Recenti Prog Med, 2000 Jan, 91(1), 16 - 9 {A rare case of cryptococcal meningitis unrelated to AIDS}; Campisi D et al.; It is presented the clinical case of a man 60 years old, heterosexual, suffering from chronic bronchopathy from old date, inveterate smoker, with previous diskotomy, herniotomy, who presents a symptomatology characterized from recurrent fever, productive cough, dyspnea, asthenia and headache for 6 month . He was admitted to hospital for fever and for a sensory slightly obnubilated . A series of investigations for typhus fever, cytomegalovirus, all with negative results were performed . He resulted negative also to the test to PPD as well as to markers of B and C hepatitis and the test for HIV . The study of the principal cancer markers also gave negative results, while the blood smears displayed leukopenia with monocytosis . The magnetic nuclear resonance of the brain showed the presence of multiple lesions of the brain and along the meninges: the examination of the liquor underlines the presence of the Cryptococcus neoformans, making to set the diagnostic of cryptococcal meningitis . The immunological study showed low values of CD4 in presence of normal values of CD8 and of a normal natural killer function . The exitus happened at 64th day . The interest of the case consists in the fact that in the medical Italian literature, unlike the international one, are not described cases of cryptococcal meningitis in patients not infected by HIV. Yeast, 2000 Mar 30, 16(5), 451 - 62 Molecular cloning and characterization of a glucan synthase gene from the human pathogenic fungus Paracoccidioides brasiliensis; Pereira M et al.; 1,3-beta-D-glucan is a fungal cell wall polymer synthesized by the multi-subunit enzyme 1,3-beta-D-glucan synthase . A subunit of this integral membrane protein was first described as the product of the FKS1 gene from Saccharomyces cerevisiae using echinocandin mutants . Other FKS1 genes were also reported for Candida albicans, Aspergillus nidulans and Cryptococcus neoformans . Here, we report the nucleotide sequence of the first homologous FKS gene cloned from the pathogenic fungus Paracoccidioides brasiliensis . An open reading frame of 5942 bp was identified in the complete sequence, interrupted by two putative introns, the first close to the 5' end and the second close to the 3' end of the gene . A promoter region is also described containing consensus sequences such as canonical TATA and CAAT boxes and, possibly, multiple sites for glucose regulation by creA protein . The deduced sequence of 1926 amino acid show more than 85% similarity to FksAp from A . nidulans, and 71% to Fks1p and Fks2p from S . cerevisiae . Computational analysis of P . brasiliensis Fks1p suggests a similar structure to transmembrane proteins, such as FksAp, with the presence of two domains composed by hydrophobic helices that limit the putative highly hydrophilic catalytic domain within the cytoplasm. J Exp Med, 2000 Mar 6, 191(5), 871 - 82 Cryptococcus neoformans STE12alpha regulates virulence but is not essential for mating; Chang YC et al.; The Cryptococcus neoformans STE12alpha gene, a homologue of Saccharomyces cerevisiae STE12, exists only in mating type (MAT)alpha cells . In S . cerevisiae, STE12 was required for mating and filament formation . In C . neoformans, haploid fruiting on filament agar required STE12alpha . The ability to form hyphae, however, was not affected by deletion of STE12alpha when convergently growing MATa strains were present . Furthermore, ste12alpha disruptants were fertile when mated with MATa strains, albeit with reduced mating frequency . Most importantly, the virulence of a ste12alpha disruptant of serotype D strain was significantly reduced in a mouse model . When the ste12alpha locus was reconstituted with the wild-type allele by cotransformation, virulence was restored . Histopathological analysis demonstrated a reduction in capsular size of yeast cells, less severe cystic lesions, and stronger immune responses in meninges of mice infected with ste12alpha cells than those of mice infected with STE12alpha cells . Using reporter gene constructs, we found that STE12alpha controls the expression of several phenotypes known to be involved in virulence, such as capsule and melanin production . These results demonstrate a clear molecular link between mating type and virulence in C . neoformans. Infection, 2000 Jan-Feb, 28(1), 3 - 7 The impact of HIV on meningitis as seen at a South African Academic Hospital (1994 to 1998); Schutte CM et al.; BACKGROUND: The increase in HIV infections in South Africa is alarming . The aim of this prospective 4-year study was to evaluate the rising incidence of HIV-related admissions due to meningitis at the Pretoria Academic Hospital (PAH) adult neurology ward and to investigate the spectrum of meningitis during this time . PATIENTS AND METHODS: Adults with meningitis presenting at the PAH neurology ward from March 1994 through February 1998 were included . HIV antibody status was determined and patients were assigned to five categories: bacterial, tuberculous, viral and cryptococcal meningitis, as well as an uncertain category . RESULTS: Over the 4-year study period 141 patients with meningitis were seen . Of these, 44 were HIV-positive (31%), with TB meningitis occurring in 16 (36%), cryptococcal meningitis in 22 (50%) and acute bacterial meningitis in three (7%) . In the first 2 years of the study, 14% of patients were HIV positive; this figure rose to 44% in the 3rd year, and 57% in the final year . The spectrum of meningitis also changed: bacterial meningitis remained relatively stable at about 25% of the total; TB meningitis almost doubled from 16% in the 1st year to 31% in the last year of the study; viral meningitis initially occurred in 8% of patients and later in 3% of cases, while cryptococcal meningitis showed the most significant increase from 6% of cases in 1994/5 to 31 and 26% respectively in the last 2 years of the study . CONCLUSION: Over a 4-year period the HIV epidemic was responsible for a marked shift in the spectrum of meningitis towards chronic infections such as TB and cryptococcal meningitis at the PAH. Antonie Van Leeuwenhoek, 2000 Jan, 77(1), 7 - 12 Molecular analyses of the IGS & ITS regions of rDNA of the psychrophilic yeasts in the genus Mrakia; Diaz MR et al.; Species of the genus Mrakia are currently classified as synonyms based on molecular sequence analyses of the large sub-unit ribosomal DNA (LrDNA) . Physiological and protein electrophoretic studies, however, reveal possible species differences . To clarify this discrepancy, we undertook molecular sequence analyses of the internal transcribed spacer (ITS) and intergenic spacer (IGS) regions of rDNA from the four psychrophilic Mrakia species and the psychrophilic yeast, Cryptococcus curiosus . Identical ITS sequences were found between C . curiosus, M . nivalis and M . frigida . Although, M . stokesii and M . gelida displayed identical ITS and IGS sequences, their sequences differed from the other three species by 2.3% and 38%, respectively . The results suggest that M . stokesii is a synonym of M . gelida, whereas M . nivalis is a synonym of M . frigida . Sequence differences (1.9%) observed in the IGS region indicates that C . curiosus is a distinct strain of M . frigida. Can J Microbiol, 2000 Jan, 46(1), 7 - 27 Diversity in the yeast Cryptococcus albidus and related species as revealed by ribosomal DNA sequence analysis; Fonseca A et al.; Evidence accumulated from studies based on physiological, biochemical, and molecular characteristics has pointed to the heterogeneity of the ubiquitous anamorphic basidiomycetous yeast species Cryptococcus albidus (Saito) Skinner, with its current varieties and synonyms . The taxonomic status of this species has not been reappraised because different studies, mostly involving limited numbers of strains, have not been integrated . To assess species diversity within the clade containing Cryptococcus albidus and other phylogenetically related Cryptococcus and Filobasidium species, we determined ribosomal DNA (rDNA) sequences of 69 strains from the 5' end of the 26S gene, D1/D2 region, and in some cases, the non-coding ITS2 region . Analysis of the sequence data together with available physiological, biochemical, and molecular characteristics, showed the segregation of C . albidus into at least 12 species, leading to the elevation of former varieties to the rank of species (C . aerius, C . diffluens), the reinstatement of synonyms (C . liquefaciens, C . terricola), and the proposal of new species (C . arrabidensis, C . chernovii, C . cylindricus, C . oeirensis, C . phenolicus, C . saitoi, C . uzbekistanensis, C . wieringae) . The overall analyses of the results argue in favour of the use of rDNA sequence data to improve species delineation when integrated with other available physiological and molecular characteristics. J Clin Microbiol, 2000 Mar, 38(3), 992 - 5 Molecular analysis of CAP59 gene sequences from five serotypes of Cryptococcus neoformans; Nakamura Y et al.; The nucleotide sequences of CAP59 genes from five serotypes of Cryptococcus neoformans were analyzed for their phylogenetic relationships . Approximately 600-bp genomic DNA fragments of the CAP59 gene were amplified from each isolate by PCR and sequenced . The CAP59 nucleotide sequences of C . neoformans showed more than 90% similarity among the five serotypes . By phylogenetic analysis, their sequences were divided into three clusters: serotypes A and AD, serotypes B and C, and serotype D . In addition, the results of reduced amino acid sequences were similar to the nucleotide sequence data . These data revealed that serotype AD was genetically close to serotype A rather than serotype D, although it had been considered to be a mixed type of serotype A and D by serological analysis . Furthermore, the nucleotide sequences of the serotype B and C isolates of C . neoformans were very similar to each other . These results indicated that serotype B and C isolates belonging to C . neoformans var . gattii were genetically homogeneous and closely related . The molecular analysis of the CAP59 gene will provide useful information for the differentiation of serotypes of C . neoformans and for an understanding of their phylogenetic relationships. Curr Microbiol, 2000 Apr, 40(4), 269 - 73 Uniparental mitochondrial transmission in sexual crosses in Cryptococcus neoformans; Xu J et al.; Restriction fragment length polymorphism (RFLP) in the large ribosomal RNA region of the mitochondrial DNA (mtDNA) was developed as a genetic marker for investigating mitochondrial transmission in sexual crosses of the human pathogenic basidiomycetous yeast Cryptococcus neoformans . Strain JEC20 of C . neoformans var . neoformans (mat a) was mated with six strains of C . neoformans var . grubii (mat alpha) . Successful mating was indicated by the formation of hyphae and basidiospores . These basidiospores were examined for mtDNA RFLP genotypes . All 570 basidiospores examined from the six crosses showed the mtDNA genotype of strain JEC20 . The failure to recover the C . neoformans var . grubii mtDNA in any cross indicates that the C . neoformans var . grubii mtDNA is either selectively eliminated in the newly formed dikaryon or selectively excluded in the immediate dikaryotic hyphae of the newly formed dikaryon. Curr Microbiol, 2000 Apr, 40(4), 250 - 6 Secondary structural and phylogenetic implications of nuclear large subunit ribosomal RNA in the ectomycorrhizal fungus Tricholoma matsutake; Hwang SK et al.; The sequence of large subunit (LSU) and 5.8S rRNA genes has been determined for Tricholoma matsutake . A secondary structure model was predicted for both LSU and 5.8S rRNAs, showing most of the structural features consistent with those of the consensus secondary structure model proposed for the eukaryotic cytoplasmic LSU rRNAs . With a reconstructed eukaryotic phylogeny based on full-length LSU rDNA sequences, T . matsutake was placed on the same branch with Cryptococcus neoformans as its closest neighbor . We proposed that T . matsutake be considered as one of the representative members of the division Basidiomycota . Here we report for the first time the complete LSU rRNA gene sequence in T . matsutake, a member of Homobasidiomycetes. Presse Med, 2000 Jan 29, 29(3), 146 - 52 {HIV infection in Africa . Clinical and therapeutical research}; Salamon R et al.; A MAJOR HEALTH PROBLEM: Human Immunodeficiency Virus (HIV) infection is a major public health problem in sub-Saharan Africa and the care of HIV-infected patients is limited by the lack of resources . Clinical research can play a major role to assess the benefit of preventive and/or curative measures adapted to the context of these countries . To illustrate advances and gaps in HIV/AIDS clinical research in Africa, we explored three issues relevant to this research: opportunistic infections in adults, mother-to-child transmission of HIV and the ethical questions . EPIDEMIOLOGY: Epidemiological African studies have shown: the omnipresence of tuberculosis, first cause of death among HIV+ patients; the frequency of bacterial infections, first cause of serious morbidity and second cause of death; the high frequency of toxoplasmosis, cryptococcal meningitis, isosporiasis, cryptosporidiasis, and other infectious syndromes of unknown etiology . More research efforts need to be done for improving tuberculosis diagnosis, compliance to treatment (evaluation of Directed Observed Therapy), resistance to treatment and primary chemoprophylaxis which has shown clear short term benefit but median term interest remains to be demonstrated . Chemoprophylaxis of opportunistic infections other than tuberculosis needs also to be evaluated: cotrimoxazole reduces the short term mortality of HIV+ patients with tuberculosis and the early serious morbidity of HIV+ patients without tuberculosis . TRANSMISSION: Mother-to-child transmission of HIV can occur during pregnancy, during delivery and the postnatal period by breastfeeding, a common practice in Africa . The overall risk of vertical transmission is estimated to be 30% but the attributable part of breastfeeding needs to be further explored . Beyond the prevention of sexual transmission of HIV among childbearing women and family planning for HIV+ women, interventions aimed to reduce mother-to-child transmission depend on the availability or not of a proposing and realising an HIV counselling and testing: antiretroviral treatments and/or breastfeeding alternatives which reduce efficaciously transmission require HIV testing, while vaginal disinfection and vitamin supplementation whom efficacy needs to be demonstrated do not . PREVENTION: Prevention of mother-to-child transmission and care of HIV+ adults in the area of opportunistic infections are feasible in Africa with an acceptable cost . This requires first to train and inform health care providers and the populations . Lots of uncertainties in these areas are likely to be alleviated by reinforcing clinical and therapeutic research of good quality including the questions of antiretroviral treatment . Ethical issues raised by the design and conduct of clinical research in Africa need a positive thinking to face the HIV African pandemic. Am J Vet Res, 2000 Feb, 61(2), 158 - 61 Fungal flora on cutaneous and mucosal surfaces of cats infected with feline immunodeficiency virus or feline leukemia virus; Sierra P et al.; OBJECTIVE: To compare cutaneous and mucosal mycoflora in cats infected with FIV or FeLV with that in noninfected cats . ANIMALS: 85 client-owned cats; 24 seropositive for FIV, 10 seropositive for FeLV, 1 seropositive for both viruses, and 50 seronegative for both viruses . PROCEDURE: Cutaneous specimens were obtained from the coat and external acoustic meatus (ear canal) and mucosal specimens from the oropharynx and rectum . Fungi were isolated from specimens, using Sabouraud dextrose agar incubated at 27 or 37 C for cutaneous and mucosal specimens, respectively . RESULTS: Fungal colonies were cultured from at least 1 specimen from 83 of 85 (97.6%) cats . The most common fungal isolates were Aspergillus spp (cultured from 59.3% of all specimens), Penicillium spp (50.0%), Cladosporium spp (44.2%), Scopulariopsis spp (41.8%), and lipophilic yeasts of the genus Malassezia (31.4%) . A greater diversity of fungal genera was isolated from retrovirus-infected cats, and Malassezia spp were more commonly recovered from these cats, compared with noninfected cats . Candida albicans, Cryptococcus neoformans, and dermatophytes (eg, Microsporum canis) were rarely isolated from any cat . Significant differences in frequency of isolation of C . neoformans and dermatophytes were not found between infected and noninfected cats . CONCLUSIONS AND CLINICAL RELEVANCE: Cats infected with FIV or FeLV may have a greater diversity of cutaneous and mucosal mycoflora than noninfected cats . However, infected cats may be no more likely than noninfected cats to expose humans to zoonotic fungi such as C . albicans, C . neoformans, and M . canis. Rev Med Interne, 2000 Jan, 21(1), 83 - 5 {Cryptococcal meningitis associated with chronic lymphocytic leukemia: a case report . Review of the literature}; Jego P et al.; INTRODUCTION: The authors report the occurrence of a cryptococcal meningitis in a patient treated by corticosteroids and polychemotherapy for a chronic lymphocytic leukemia . EXEGESIS: A 63-year-old man with chronic lymphocytic leukemia was sent to hospital because of impaired condition with fever . Neurological disorders appeared . Cryptococcal meningitis was diagnosed . Under treatment, the outcome was favorable . CONCLUSION: This paper highlights the feature of this infection most likely underestimated in HIV-seronegative patients and the need to a priori consider this diagnosis. FEMS Immunol Med Microbiol, 2000 Mar, 27(3), 191 - 200 Involvement of endogenously synthesized interleukin (IL)-18 in the protective effects of IL-12 against pulmonary infection with Cryptococcus neoformans in mice; Kawakami K et al.; We previously demonstrated that interleukin (IL)-12 protected mice against fatal pulmonary infection with a highly virulent strain of Cryptococcus neoformans, which correlated well with the production of interferon (IFN)-gamma as well as IL-18 in the primary infected site . In the present study, we examined the role of endogenously synthesized IL-18 in IL-12-induced host resistance to this pathogen . There was little or no production of IFN-gamma and IL-18 both at mRNA and protein levels in lungs of mice infected with C . neoformans, while treatment with IL-12 induced a marked production of these cytokines . Caspase-1 mRNA was expressed in infected mice even without IL-12 treatment . Administration of neutralizing anti-IFN-gamma monoclonal antibody (mAb) clearly inhibited production of IFN-gamma and IL-18 induced by IL-12, while control IgG did not show such an effect . However, administration of IFN-gamma did not induce the production of both cytokines in infected mice, although tumor necrosis factor (TNF)-alpha and IFN-gamma-inducible protein (IP)-10 were synthesized by the same treatment . Finally, neutralizing anti-IL-18 antibody (Ab) significantly interfered with the production of IFN-gamma and elimination of the microorganism from the lung induced by IL-12 treatment . Furthermore, both IFN-gamma synthesis and host protection caused by IL-12 were profoundly diminished in IL-18 gene-disrupted mice . Considered collectively, our results indicated that host protection against C . neoformans induced by IL-12 involved endogenously synthesized IL-18 and that the production of IL-18 was mediated at least in part by endogenous IFN-gamma. J Clin Lab Anal, 2000, 14(2), 73 - 82 Immunoassays for pentamidine and related compounds: development of a facile inhibitory ELISA suitable for clinical use; Reisner HM et al.; Aromatic dicationic drugs have a broad spectrum of activity against protozoal and fungal pathogens including Pneumocystis carinii, Leishmania mexicana amazonensis, Cryptosporidium parvum and Cryptococcus neoformans . Pentamidine serves as the exemplar for an extensive collection of newly synthesized related compounds, which have reduced toxicity and a wider range of target organisms . Assays of pentamidine and related compounds have depended on HPLC-tandem mass spectrometry (HPLC-TMS) for the quantitation and identification of drug and metabolites . Immunoassays for pentamidine would have many advantages over the HPLC methods including relative simplicity of assay format and required equipment, convenience in sample preparation and reduction in time and cost of assays . In this report we describe a simple ELISA based immunoassay for pentamidine and pentamidine-like drugs with requisite sensitivity and specificity for use as a clinical assay (EC50 value of about 50 nanomolar) . Immunogen was synthesized by coupling the hapten aminopentamidine to ovalbumin (chemically modified to provide an optimal number of -SH groups) using sulfo-MBS . Maleic-anhydride activated ELISA plates were covalently sensitized using the aminopentamidine hapten and used in an inhibitory ELISA assay format whereby the ability of analyte to suppress antibody binding to sensitized plate was measured . The assay detects primarily the phenolic amidine of pentamidine when in a para position and hence can also detect structurally related derivatives of pentamidine of potential interest as new therapeutic agents . Mycoses, 1999, 42(11-12), 629 - 39 In vitro susceptibility of yeasts for fluconazole and itraconazole . Evaluation of a microdilution test; Nenoff P et al.; In vitro susceptibilities were determined for a total of 159 clinical isolates and 12 reference strains of yeasts belonging to different Candida species including 94 Candida albicans strains, and further genera such as Cryptococcus, Trichosporon, Geotrichum and Saccharomyces . Minimum inhibitory concentration (MIC) values for fluconazole and itraconazole were assessed using a microdilution technique with the semisynthetic high resolution (HR) medium supplemented with glucose and asparagine but without sodium hydrogen carbonate (pH 7.0), according to a proposal of the working group 'Clinical Mycology' of the German Speaking Mycological Society . Fluconazole MIC values for C . albicans were between 0.125 and > or = 128 micrograms ml-1 . Thus, the median of 1 microgram ml-1 showed that the overall fluconazole susceptibility was good . As expected, Candida krusei (seven strains) exhibited diminished in vitro susceptibility with MIC values for fluconazole of 8 to 128 micrograms ml-1 with a median of 64 micrograms ml-1 . Some Candida kefyr strains seemed to be less susceptible against fluconazole which was indicated by a MIC90 of 64 micrograms ml-1 . Surprisingly, no Candida glabrata isolate exhibited a MIC value greater than 16 micrograms ml-1 . Other Candida species, Trichosporon cutaneum, Geotrichum candidum and Saccharomyces cerevisiae showed low MICs to fluconazole . In vitro susceptibility testing of itraconazole revealed that all Candida species except C . albicans, but also Trichosporon cutaneum, Geotrichum candidum, and Saccharomyces cerevisiae exhibited acceptable low MIC values against itraconazole (0.03-2 micrograms ml-1) . Their MIC90 values for itraconazole were in the close range between 0.125 and 2 micrograms ml-1 . MIC values between 0.125 and 2 micrograms ml-1 were obtained, even for C . krusei strains . On the other hand, the range of C . albicans MICs was between 0.0125 and > or = 16 micrograms ml-1 with MIC50 and MIC90 values of 0.125 and > or = 16 micrograms ml-1, respectively, indicating that a considerable number of yeast strains have high MICs . The comparative evaluation of different experimental conditions revealed that there exists a marked influence both of inoculum size and incubation time on the results of susceptibility testing . Therefore, for routine usage 10(2) CFU ml-1 and 18-24 h incubation time for this microdilution method with HR medium are recommended. Mycoses, 1999, 42(11-12), 601 - 8 Killer activity at different pHs against Cryptococcus neoformans var . neoformans serotype A by environmental yeast isolates; Criseo G et al.; Yeast isolates that share the same habitats as Cryptococcus neoformans var . neoformans serotype A in a restricted Mediterranean area were assayed in order to verify their killer activity against Cr . neoformans strains isolated from clinical and environmental sources . Many of the environmental yeast isolates expressed the killer phenomenon against the assayed strains of Cr . neoformans . Two species of Candida: Candida parapsilosis and Candida famata, and Pichia carsonii, were the most active killers at pH 4.6, 5.0 and 5.6 levels encountered in pigeon and canary guanos . Killer activity by C . parapsilosis is reported for the first time . The authors hypothesized that the killer phenomenon exerted by yeast species with heavy killer activity against Cr . neoformans would lend themselves for use as biological control agents against sensitive strains of Cr . neoformans when directly inoculated into the habitats of Cr . neoformans. Antimicrob Agents Chemother, 2000 Mar, 44(3), 739 - 46 Synergistic antifungal activities of bafilomycin A(1), fluconazole, and the pneumocandin MK-0991/caspofungin acetate (L-743,873) with calcineurin inhibitors FK506 and L-685,818 against Cryptococcus neoformans; Del Poeta M et al.; Cryptococcus neoformans is an opportunistic fungal pathogen that causes life-threatening infections of the central nervous system . Existing therapies include amphotericin B, fluconazole, and flucytosine, which are limited by toxic side effects and the emergence of drug resistance . We recently demonstrated that the protein phosphatase calcineurin is required for growth at 37 degrees C and virulence of C . neoformans . Because calcineurin is the target of potent inhibitors in widespread clinical use, cyclosporine and FK506 (tacrolimus), it is an attractive drug target for novel antifungal agents . Here we have explored the synergistic potential of combining the calcineurin inhibitor FK506 or its nonimmunosuppressive analog, L-685,818, with other antifungal agents and examined the molecular basis of FK506 action by using genetically engineered fungal strains that lack the FK506 target proteins FKBP12 and calcineurin . We demonstrate that FK506 exhibits marked synergistic activity with the H(+)ATPase inhibitor bafilomycin A(1) via a novel action distinct from calcineurin loss of function . FK506 also exhibits synergistic activity with the pneumocandin MK-0991/caspofungin acetate (formerly L-743,873), which targets the essential beta-1,3 glucan synthase, and in this case, FK506 action is mediated via FKBP12-dependent inhibition of calcineurin . Finally, we demonstrate that FK506 and fluconazole have synergistic activity that is independent of both FKBP12 and calcineurin and may involve the known ability of FK506 to inhibit multidrug resistance pumps, which are known to export azoles from fungal cells . In summary, our studies illustrate the potential for synergistic activity of a variety of different drug combinations and the power of molecular genetics to define the mechanisms of drug action, as well as identify a novel action of FK506 that could have profound implications for therapeutic or toxic effects in other organisms, including humans. J Infect Dis, 2000 Feb, 181(2), 791 - 4 Stimulation of macrophage inflammatory protein-1alpha, macrophage inflammatory protein-1beta, and RANTES by Candida albicans and Cryptococcus neoformans in peripheral blood mononuclear cells from persons with and without human immunodeficiency virus infection; Huang C et al.; The beta-chemokine macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, and RANTES are critical for recruitment of inflammatory cells into infected tissue . Moreover, by binding to the human immunodeficiency virus (HIV) coreceptor CCR5, release of these chemokines could influence the course of HIV infection . beta-chemokine gene expression and release was determined by ELISA and RNase protection assay, respectively, in peripheral blood mononuclear cells (PBMC) from HIV-negative and -positive persons stimulated with Candida albicans and Cryptococcus neoformans, 2 fungi common in HIV-infected persons . Gene expression and/or release of all 3 chemokines was seen in response to both fungi although C . albicans was more potent than C . neoformans . Fungal stimulated chemokine production by HIV-positive PBMC was similar to that in HIV-negative PBMC, suggesting that the scant inflammatory response often seen in AIDS patients with cryptococcosis and candidiasis is not secondary to suboptimal beta-chemokine release. J Infect Dis, 2000 Feb, 181(2), 733 - 6 Effect of interleukin (IL)-15 priming on IL-12 and interferon-gamma production by pathogen-stimulated peripheral blood mononuclear cells from human immunodeficiency virus-seropositive and -seronegative donors; Parayath KE et al.; Hypoproduction of the cytokines interleukin (IL)-12 and interferon (IFN)-gamma is thought to contribute to the impaired immunity seen in human immunodeficiency virus (HIV)-infected persons . The effects of priming with IL-15 on the production of IL-12 and IFN-gamma by stimulated peripheral blood mononuclear cells (PBMC) from HIV-seronegative and -seropositive donors were studied . Stimuli included 3 pathogens that commonly infect HIV-positive persons-Cryptococcus neoformans, Candida albicans, and Mycobacterium tuberculosis-plus Staphylococcus aureus . Following IL-15 priming of HIV-negative PBMC, pathogen-stimulated IL-12 and IFN-gamma production increased 5-58-fold . However, for the HIV-positive PBMC, IL-15 priming did not lead to significant increases in pathogen-stimulated IL-12 production and caused only modest increases in IFN-gamma production . These data suggest that IL-15 alone may be insufficient to correct the defect in IL-12 and IFN-gamma production in HIV-positive persons. Arq Neuropsiquiatr, 1999 Sep, 57(3A), 678 - 82 Pseudocystic form of neurocryptococcosis in pregnancy . Case report; Nucci A et al.; We report a case of neurocryptococcosis which is unique in the literature because the patient had a pseudocystic form of the disease during pregnancy and without any evidence of AIDS . The clinical picture was that of intracranial hypertension and the epidemiological background was highly suggestive of cysticercosis . CT showed multiple round hypodense lesions in the basal ganglia and cerebellum, without contrast enhancement . Since a scolex was not visible, the diagnosis of neurocysticercosis was considered probable . CSF examination was not performed in view of its high risk . The patient had progressive downhill course . Autopsy disclosed multiple gelatinous pseudocysts in the cerebral and cerebellar gray matter, containing abundant Cryptococcus neoformans . Meningeal involvement was minimal . The child was delivered by caesarean section and was free of infection, but died later of hyaline membrane disease . The neuroimaging appearances of this rare instance of the pseudocystic form of neurocryptococcosis mimicked closely neurocysticercosis and only postmortem examination allowed correct diagnosis . The pseudocystic form has so far only been reported in AIDS. Arq Neuropsiquiatr, 1999 Sep, 57(3A), 649 - 52 {Prognosis factors in cryptococcal meningoencephalitis}; Darze C et al.; OBJECTIVE: To identify demographic, clinical and cerebrospinal fluid (CSF) variables associated to intrahospitalar lethality of patients with cryptococcal meningoencephalitis . STUDY DESIGN: Retrospective cohort to study prognosis . SETTING: Hospital Couto Maia (HCMaia) reference for patients with infectious diseases in the State of Bahia Northeastern Brazil . POPULATION: Patients admitted at HCMaia, from 1972 to 1996, with the diagnosis of cryptococcal meningoencephalitis . RESULTS: Lethality rate was 42.7% . The most important neurological abnormalities were neck stiffness, decreased consciousness level, behavior changes, cranial nerve palsy and visual alteration . Disease time over 30 days, involvement of consciousness level and cerebrospinal fluid cells under 40/mm3 were associated to a higher lethality rate . CONCLUSION: Disease time over 30 days, involvement of consciousness level, and CSF decreased cellularity were the only predictors of lethality in the studied population. Neuroradiology, 2000 Jan, 42(1), 30 - 3 MRI demonstration of intracerebral cryptococcal granuloma; Kamezawa T et al.; We report an intracerebral cryptococcal granuloma in a patient who presented with recent memory disturbance and deteriorating mental status followed by temporary loss of consciousness . To our knowledge, this is the first reported case of an intracerebral cryptococcal granuloma examined by a combination of conventional MRI, fluid-attenuated inversion-recovery and diffusion-weighted imaging and in which the surgical specimen was analysed histochemically. J Antimicrob Chemother, 2000 Feb, 45(2), 239 - 42 In vitro susceptibility studies of Cryptococcus neoformans isolated from patients with no clinical response to amphotericin B therapy; Rodero L et al.; The in vitro activities of three antifungal drugs alone and in combination were evaluated against five isolates of Cryptococcus neoformans using time-kill curves (TKC) . The isolates were from AIDS patients who had either died or had failed to show a clinical response during amphotericin B (AMB) treatment . AMB, fluconazole (FCZ) and flucytosine (5FC), and combinations of the drugs (AMB plus 5FC, AMB plus rifampicin (RIF) and FCZ plus 5FC), were evaluated . With all five isolates AMB did not show fungicidal activity; instead, a persistent or tolerant effect was observed . Combinations of AMB plus 5FC and AMB plus RIF showed a clear synergic effect, except for one isolate tested with AMB plus RIF . In contrast, the FCZ plus 5FC combination did not inhibit growth of any isolate. J Immunol, 2000 Feb 15, 164(4), 2021 - 7 CCR2 expression determines T1 versus T2 polarization during pulmonary Cryptococcus neoformans infection; Traynor TR et al.; Pulmonary clearance of the encapsulated yeast Cryptococcus neoformans requires the development of T1-type immunity . The objective of this study was to determine the role of CCR2 in leukocyte recruitment and development of T1-type cell-mediated immunity during pulmonary C . neoformans infection . Intratracheal inoculation of C . neoformans into CCR2 knockout (CCR2-/-) mice produced a prolonged pulmonary infection (5000-fold CFU at 6 wk compared with CCR2+/+ mice) and significant dissemination to the spleen and brain (160- and 800-fold greater) . In addition, CCR2 deficiency resulted in significantly reduced recruitment of macrophages (weeks 1-3) and CD8+ T cells (weeks 1-2) into the lungs . The immune response in CCR2-/- mice was characterized by chronic pulmonary eosinophilia, crystal deposition in the lungs, pulmonary leukocyte production of IL-4 and IL-5 but not IFN-gamma, lack of anticryptococcal delayed-type hypersensitivity, and high levels of serum IgE . These results demonstrate that expression of CCR2 is required for the development of a T1-type response to C . neoformans infection and lack of CCR2 results in a switch to a T2-type response . Thus, CCR2 plays a critical role in promoting the development of T1- over T2-type immune responses in the lung following cryptococcus infection. J Clin Microbiol, 2000 Feb, 38(2), 926 - 8 Temperature-sensitive strain of Cryptococcus neoformans producing hyphal elements in a feline nasal granuloma; Bemis DA et al.; We report the isolation of a temperature-sensitive, serotype A, mating type alpha strain of Cryptococcus neoformans from a case of nasal cryptococcosis in a cat . The strain grew extremely slowly at 35 degrees C and failed to grow at 37 degrees C in vitro . Histopathological sections of the infected tissue revealed yeast cells producing hyphae up to several hundred micrometers in length, in addition to numerous encapsulated yeast cells typical of C . neoformans . The cultures grown on yeast extract-peptone-glucose agar at 35 degrees C also produced some yeast cells with germ tube-like hyphal elements up to 100 microm in length. World J Urol, 1999 Dec, 17(6), 410 - 4 Fungal infections of the urinary tract; Sobel JD et al.; Funguria, fungal urinary tract infections, are most commonly caused by Candida species but may also be caused by Cryptococcus neoformans, Aspergillus species, and the endemic mycoses . Candiduria presents as an increasingly common nosocomial infection, which may involve all anatomic levels of the urinary tract, resulting in a spectrum of disease varying from asymptomatic candiduria to clinical sepsis . Although several successful systemic or local therapeutic options exist for the eradication of candiduria, knowledge of the pathogenesis and natural history of candiduria has lagged . This has resulted in confusion among practitioners as to when antifungal therapy is indicated . Treatment guidelines have recently been formulated and are described herein. Ann Intern Med, 2000 Feb 1, 132(3), 205 - 8 Evidence of zoonotic transmission of Cryptococcus neoformans from a pet cockatoo to an immunocompromised patient; Nosanchuk JD et al.; BACKGROUND: Although cryptococcosis has been associated with birds for almost 50 years, point sources for infection have not been identified . OBJECTIVE: To document zoonotic transmission of Cryptococcus neoformans . DESIGN: Case report . SETTING: A home in Boston, Massachusetts . PATIENT: A 72-year-old woman who received a diagnosis of cryptococcal meningitis in November 1998 . The patient, who had been taking immunosuppressant drugs since undergoing renal transplantation in 1989, owned a pet cockatoo . MEASUREMENTS: Cryptococcus neoformans was isolated from the feces of the cockatoo . Isolates from excreta and from the patient were compared by using biochemical profiles, monoclonal antibody binding patterns, restriction fragment length polymorphism analysis, and karyotyping . RESULTS: The isolates from the patient and the cockatoo had identical biochemical profiles, the same monoclonal antibody immunofluorescence patterns, and indistinguishable patterns on restriction fragment length polymorphism analysis and karyotyping . CONCLUSIONS: The indistinguishable patient and cockatoo isolates strongly suggest that the patient's infection resulted from exposure to aerosolized cockatoo excreta . Although the incidence of cryptococcal infection due to such exposure is unknown, it may be prudent to advise immunocompromised patients to avoid pet birds and avian excreta. J Eukaryot Microbiol, 2000 Jan-Feb, 47(1), 15 - 20 Protists as opportunistic pathogens: public health impact in the 1990s and beyond; Kaplan JE et al.; Protist organisms (protozoa and fungi) have become increasingly prominent as opportunistic pathogens among persons infected with human immunodeficiency virus (HIV) and among organ transplant recipients--two immunocompromised populations that have increased dramatically in the past two decades . Pneumocystis carinii pneumonia continues to be the most common serious opportunistic infection (OI) among HIV-infected persons in the United States, occurring frequently among persons not previously receiving medical care . Toxoplasmosis, cryptococcosis, cryptosporidiosis, and isosporiasis occur frequently in HIV-infected persons in the developing world . Candidiasis and aspergillosis are common OIs in organ transplant recipients . As these populations of immunosuppressed patients continue to expand worldwide new OIs caused by protist pathogens are likely to emerge. Med Mycol, 1999 Dec, 37(6), 375 - 89 Antioxidant systems in the pathogenic fungi of man and their role in virulence; Hamilton AJ et al.; In the last two decades, a variety of fungal antioxidants have attracted considerable interest, largely arising from their hypothetical role as virulence determinants . Melanin is a potent free radical scavenger and in Cryptococcus neoformans, there is now good evidence that the production of melanin is a significant virulence determinant . There is also recent evidence linking melanin biosynthesis to the virulence of Aspergillus fumigatus conidia . Superoxide dismutases are important housekeeping antioxidants and have an additional hypothetical role in virulence; however, although these enzymes have been biochemically characterized from Aspergillus and Cryptococcus, there is as yet no firm evidence that these enzymes are involved in pathogenicity . Catalase production may play some role in the virulence of Candida albicans but this enzyme has not been shown, as yet, to influence the virulence of A . fumigatus . There are some data supporting an antioxidant function for the acyclic hexitol mannitol in C . neoformans, but further investigations are required in this area . Research into the putative antioxidant activities of a range of other fungal enzymes, such as acid phosphatases, remains limited at this time. Postgrad Med J, 2000 Feb, 76(892), 85 - 8 Cryptococcosis in AIDS; Imwidthaya P et al.; A total of 87 patients (17 female, 70 male) were admitted to SIRIRAJ HOSPITAL, MAHIDOL UNIVERSITY, BANGKOK, THAILAND, from JANUARY 1996 TO DECEMBER 1997, with a diagnosis of cryptococcal meningitis and underlying AIDS . The age range was 14: 70 years, mean 32.1 . Six females (35%) and thirty-one males (44%) died, while the others were discharged home after clinical improvement . The mean duration of admission of those who died was 14.5 days, which was shorter than that of the patients who survived (25.7 days) . Cerebral cryptococcosis was diagnosed using culture (100%), India ink preparation (91%), latex agglutination test (100%), and polymerase chain reaction (86%) . Polymerase chain reaction fingerprinting of Cryptococcus neoformans revealed 99% serotype A and 1% serotype B . The mean minimum inhibitory concentrations of amphotericin B, flucytosine, fluconazole and itraconazole against 87 isolates of C neoformans were 0.55 microg/ml (0.25-1, SD = 0.22), 9.5 microg/ml (2-20, SD = 4.91), 6.9 microg/ml (1-16, SD = 4.42) and 0.36 microg/ml (0.125-1.0, SD = 0.23), respectively . These findings showed that the cryptococcal infections were sensitive to these antifungal agents. Antimicrob Agents Chemother, 2000 Feb, 44(2), 400 - 4 Influence of shaking on antifungal susceptibility testing of Cryptococcus neoformans: a comparison of the NCCLS standard M27A medium, buffered yeast nitrogen base, and RPMI-2% glucose; Rodr inverted question markiguez-Tudela JL et al.; Cryptococcus neoformans is a nonfermentative yeast that requires oxygen for growth . The shaking of culture media achieves good oxygenation, promoting the growth of cryptococci . In this study, three test media (RPMI 1640, RPMI 1640-2% glucose, and buffered yeast nitrogen base inverted question markBYNB) recommended in the National Committee for Clinical Laboratory Standards M27A standard were examined . Growth abilities and minimum inhibitory concentrations (MICs) in microplates incubated at 35 degrees C for 48 h were determined . The results indicated that shaking and an inoculum size of 10(5) CFU/ml yielded optimal growth of this yeast . Compared to RPMI 1640, supplementation of RPMI 1640 with 2% glucose did not significantly improve growth of C . neoformans and resulted in an 8.7-h delay of exponential growth . Cryptococcal growth in RPMI 1640 at 24 h was notably better than that in RPMI-2% glucose, although by 48 h the growths were comparable . The MIC range of amphotericin B observed for the C . neoformans strains grown in RPMI 1640 with or without glucose was too narrow to allow the separation of susceptible and resistant strains based on clinical outcome . The widest ranges of MICs of flucytosine and fluconazole were obtained with BYNB . This work demonstrates the need for a new antifungal susceptibility test for C . neoformans. Infect Immun, 2000 Feb, 68(2), 982 - 5 Comparison of the roles of calcineurin in physiology and virulence in serotype D and serotype A strains of Cryptococcus neoformans; Cruz MC et al.; The calcineurin gene was cloned and disrupted in serotype D strains of Cryptococcus neoformans . Serotype A and serotype D calcineurin mutants were inviable at 37 degrees C and avirulent in mice, whereas only serotype A mutants were cation stress sensitive . Thus, calcineurin plays conserved and divergent roles in serotype A and serotype D strains. Infect Immun, 2000 Feb, 68(2), 832 - 8 Persistent Cryptococcus neoformans pulmonary infection in the rat is associated with intracellular parasitism, decreased inducible nitric oxide synthase expression, and altered antibody responsiveness to cryptococcal polysaccharide; Goldman DL et al.; Fungal pathogens are notorious for causing chronic and latent infections, but the mechanism by which they evade the immune response is poorly understood . A major limitation in the study of chronic fungal infection has been the lack of suitable animal models where the infection is controlled and yet persists . Pulmonary Cryptococcus neoformans infection in rats results in a diffuse pneumonitis that resolves without dissemination or scarring except for the persistence of interstitial and subpleural granulomas that harbor viable cryptococci inside macrophages and epithelioid cells . Infected rats are asymptomatic but remain infected for as long as 18 months after inoculation with C . neoformans . Containment of infection is associated with granuloma formation that can be partially abrogated by glucocorticoid administration . Using this model, we identified several features associated with persistent infection in the rat lung, including (i) localization of C . neoformans to discrete, well-organized granulomas; (ii) intracellular persistence of C . neoformans within macrophages and epithelioid cells; (iii) reduced inducible nitric oxide synthase expression by granulomas harboring C . neoformans; and (iv) reduced antibody responses to cryptococcal polysaccharide . The results show that maintenance of persistent infection is associated with downregulation of both cellular and humoral immune responses. Infect Immun, 2000 Feb, 68(2), 558 - 63 Early induction of interleukin-12 by human monocytes exposed to Cryptococcus neoformans mannoproteins; Pitzurra L et al.; Interleukin-12 (IL-12) production by human monocytes stimulated with mannoproteins (MPs) of Cryptococcus neoformans was investigated . The results reported show that secreted or cell-associated MPs induce an early and significant production of IL-12 . MPs show different capabilities to quantitatively affect IL-12 production; MP2, an 8 . 2-kDa MP purified from the culture supernatant of C . neoformans, appears to be the most potent stimulator . Cytochalasin B inhibits both internalization and IL-12 induction by MP . In addition, a drastic reduction of IL-12 was observed when monocytes were cultured in the absence of normal human serum or treated with soluble mannan . Early production of IL-12 promotes early secretion of gamma interferon by T cells but does not influence the magnitude of the MP-induced lymphoproliferative response . Overall our results identify cryptococcal antigens responsible for rapid and potent induction of IL-12 in monocytes . MPs appear to regulate IL-12 secretion by internalization via the endocytic pathway and by interaction with monocyte receptors or serum factors. Infect Immun, 2000 Feb, 68(2), 456 - 62 Requirement for CD4(+) T lymphocytes in host resistance against Cryptococcus neoformans in the central nervous system of immunized mice; Buchanan KL et al.; The importance of cell-mediated immunity (CMI) and CD4(+) T lymphocytes in host resistance against Cryptococcus neoformans is well documented and is exemplified by the high susceptibility to progressive infection with this pathogen of AIDS patients with reduced CD4(+) T-cell numbers . Although much has been learned about the role of CMI in the clearance of C . neoformans from the lungs and other internal organs, less is known about the protective mechanisms in the brain, the organ most frequently involved with a fatal outcome of cryptococcosis . We hypothesized that host resistance mechanisms against C . neoformans in the central nervous system (CNS) were similar to those outside the CNS (i.e., gamma interferon {IFN-gamma}, CD4(+) T cells, and others) . To test this hypothesis, we used a murine model of cryptococcal meningitis whereby cryptococci are introduced directly into the CNS . In experiments where mice were immunized to mount an anticryptococcal CMI response, our results indicate that immunization induced protective mechanisms that could be detected in the CNS by inhibition of the growth of viable yeast cells . Flow cytometric analyses of leukocytes in brain and spinal cord homogenates revealed that T lymphocytes, macrophages, and neutrophils accumulated in C . neoformans-infected brains of immune mice . In vivo depletion of CD4(+) T cells, but not CD8(+) T cells, resulted in significantly reduced leukocyte accumulation in the brains of immune mice . Furthermore, depletion of CD4(+) T cells or neutralization of IFN-gamma exacerbated CNS infection in immune mice, suggesting a critical role for CMI mechanisms in acquired protection in the CNS. Infect Immun, 2000 Feb, 68(2), 443 - 8 Urease as a virulence factor in experimental cryptococcosis; Cox GM et al.; Urease catalyzes the hydrolysis of urea to ammonia and carbamate and has been found to be an important pathogenic factor for certain bacteria . Cryptococcus neoformans is a significant human pathogenic fungus that produces large amounts of urease; thus we wanted to investigate the importance of urease in the pathogenesis of cryptococcosis . We cloned and sequenced the genomic locus containing the single-copy C . neoformans urease gene (URE1) and used this to disrupt the native URE1 in the serotype A strain H99 . The ure1 mutant strains were found to have in vitro growth characteristics, phenoloxidase activity, and capsule size similar to those of the wild type . Comparison of a ure1 mutant with H99 after intracisternal inoculation into corticosteroid-treated rabbits revealed no significant differences in colony counts recovered from the cerebrospinal fluid . However, when these two strains were compared in both the murine intravenous and inhalational infection models, there were significant differences in survival . Mice infected with a ure1 strain lived longer than mice infected with H99 in both models . The ure1 strain was restored to urease positivity by complementation with URE1, and two resulting transformants were significantly more pathogenic than the ure1 strain . Our results suggest that urease activity is involved in the pathogenesis of cryptococcosis but that the importance may be species and/or infection site specific. Arzneimittelforschung, 1999 Dec, 49(12), 1035 - 8 Synthesis and in vitro antifungal activity of 2-aryl-5-phenylsulfonyl-1,3,4-thiadiazole derivatives; Foroumadi A et al.; The synthesis and antifungal activity of a series of 2-nitroaryl-5-phenylsulfonyl-1,3,4-thiadiazoles (5a-e) are described . The in vitro antifungal activity of the compounds was determined against a variety of fungal strains in comparison to miconazole (CAS 22916-47-8) and fluconazole (CAS 86386-73-4) . Two derivatives (5d, 5e) showed high activity against Candida albicans and Candida spp . having MIC values ranging from 0.048-3.12 micrograms/ml, providing higher potencies than the reference drug fluconazole . Compound 5a also showed high activity against Cryptococcus neoformans (MIC < 0.048 microgram/ml) . The activity of this compound against Aspergillus niger and Aspergillus fumigatus was moderate (MIC = 1.56-6.25 micrograms/ml), while fluconazole was inactive . Moreover, the nitroimidazole derivative 5d possessed good activity against most fungal strains in comparison to fluconazole. AIDS, 2000 Nov 10, 14(16), 2515 - 21 HIV infection in Haiti: natural history and disease progression; Deschamps MM et al.; OBJECTIVE: A study was conducted to define the natural history and disease progression of HIV infection in a developing country . DESIGN: A prospective longitudinal cohort study . METHODS: Forty-two patients with documented dates of HIV seroconversion were followed in Port-au-Prince, Haiti . Patients were seen at 3 month intervals or when ill . Patients were treated for bacterial, mycobacterial, parasitic, and fungal infections, but antiretroviral therapy was not available . Patients were followed until death or until 1 January 2000; median follow-up was 66 months . RESULTS: By Kaplan-Meier analyses, the median time to symptomatic HIV disease (CDC category B or C) was 3.0 years {95% confidence interval (CI) 2.3-5.0 years} . The median time to AIDS (CDC category C) was 5.2 years (95% CI 4.7-6.5 years), and the median time to death was 7.4 years (95% CI 6.2-10.2 years) . Community-acquired infections, including respiratory tract infections, acute diarrhea, and skin infections were common in the pre-AIDS period . AIDS-defining illnesses included tuberculosis, wasting syndrome, cryptosporidiosis, cyclosporiasis, candida esophagitis, toxoplasmosis, and cryptococcal meningitis . Rapid progression to death was associated with anemia at the time of seroconversion hazards ratio (HR) 4.1 (95% CI 1.1-15.0), age greater than 35 years at seroconversion HR 4.4 (95% CI 1.1-16.6), and lymphopenia at seroconversion HR 11.0 (95% CI 2.3-53.0) . CONCLUSION: This report documents rapid disease progression from HIV seroconversion until death among patients living in a developing country . Interventions, including nutritional support and prophylaxis of common community-acquired infections during the pre-AIDS period may slow disease progression and prolong life for HIV-infected individuals in less-developed countries. Clin Microbiol Rev, 2000 Jan, 13(1), 122 - 43, table of contents Potential role of phospholipases in virulence and fungal pathogenesis; Ghannoum MA; Microbial pathogens use a number of genetic strategies to invade the host and cause infection . These common themes are found throughout microbial systems . Secretion of enzymes, such as phospholipase, has been proposed as one of these themes that are used by bacteria, parasites, and pathogenic fungi . The role of extracellular phospholipase as a potential virulence factor in pathogenic fungi, including Candida albicans, Cryptococcus neoformans, and Aspergillus, has gained credence recently . In this review, data implicating phospholipase as a virulence factor in C . albicans, Candida glabrata, C . neoformans, and A . fumigatus are presented . A detailed description of the molecular and biochemical approaches used to more definitively delineate the role of phospholipase in the virulence of C . albicans is also covered . These approaches resulted in cloning of three genes encoding candidal phospholipases (caPLP1, caPLB2, and PLD) . By using targeted gene disruption, C . albicans null mutants that failed to secrete phospholipase B, encoded by caPLB1, were constructed . When these isogenic strain pairs were tested in two clinically relevant murine models of candidiasis, deletion of caPLB1 was shown to lead to attenuation of candidal virulence . Importantly, immunogold electron microscopy studies showed that C . albicans secretes this enzyme during the infectious process . These data indicate that phospholipase B is essential for candidal virulence . Although the mechanism(s) through which phospholipase modulates fungal virulence is still under investigations, early data suggest that direct host cell damage and lysis are the main mechanisms contributing to fungal virulence . Since the importance of phospholipases in fungal virulence is already known, the next challenge will be to utilize these lytic enzymes as therapeutic and diagnostic targets. Clin Infect Dis, 2000 Jan, 30(1), 47 - 54 Diagnosis and management of increased intracranial pressure in patients with AIDS and cryptococcal meningitis . The NIAID Mycoses Study Group and AIDS Cooperative Treatment Groups; Graybill JR et al.; This study was undertaken to characterize the laboratory and clinical course of patients with AIDS and cryptococcal meningitis who had normal or elevated cerebrospinal fluid (CSF) pressure . Data were obtained retrospectively from a randomized multicenter quasifactorial phase III study comparing amphotericin B with or without flucytosine in primary treatment of cryptococcal meningitis . CSF pressure was measured before treatment and at 2 weeks . Repeated lumbar punctures were done to drain CSF and to reduce pressure . Patients with the highest baseline opening pressures (> or = 250 mm H2O) were distinguished by higher titers of cryptococcal capsular polysaccharide antigen in CSF; more frequently positive India ink smears of CSF; and more frequent headache, meningismus, papilledema, hearing loss, and pathological reflexes . After receiving antifungal therapy, those patients whose CSF pressure was reduced by >10 mm or did not change had more frequent clinical response at 2 weeks than did those whose pressure increased >10 mm (P<.001) . Patients with pretreatment opening pressure <250 mm H2O had increased short-term survival compared with those with higher pressure . We recommend that opening pressures >/=250 mm H2O be treated with large-volume CSF drainage. Clin Infect Dis, 2000 Jan, 30(1), 29 - 34 Disseminated infection due to rapidly growing mycobacteria in immunocompetent hosts presenting with chronic lymphadenopathy: a previously unrecognized clinical entity; Chetchotisakd P et al.; Disseminated infection due to rapidly growing mycobacteria is uncommon and occurs mostly in immunocompromised patients . We report 16 cases of such infection with an unusual presentation seen at Srinagarind Hospital, a university hospital in northeastern Thailand . The clinical features were different from those in previous reports . All of the patients presented with chronic bilateral cervical lymphadenopathy . Twelve had mycobacterial involvement of other organs (sinuses, 6 patients; lungs, 4; liver, 4; spleen, 3; skin, 3; bone and joint, 2; and tonsils, 2) . An interesting occurrence in 11 patients was 14 episodes of reactive skin manifestations (Sweet's syndrome, 9; generalized pustulosis and erythema nodosum, 2 each; and pustular psoriasis, 1) . No identifiable predisposing factors, including human immunodeficiency disease, were found in these patients . However, 8 patients had 11 episodes of prior infection or coinfection with other opportunistic pathogens (salmonellosis, 4; penicilliosis, 3; pulmonary tuberculosis, 2; and melioidosis and cryptococcosis, 1 each) . These findings suggest that cell-mediated immunity is defective in these patients. Clin Diagn Lab Immunol, 2000 Jan, 7(1), 125 - 8 Development of positive selectable markers for the fungal pathogen Cryptococcus neoformans; Hua J et al.; Cryptococcus neoformans is an opportunistic fungal pathogen that causes meningitis in approximately 10% of patients with AIDS . New selectable markers which confer resistance to G418 or phleomycin when transformed into C . neoformans were made . A hygromycin-selectable marker was modified to allow selection with a single copy of the marker. Gastroenterol Clin Biol, 1999 Nov, 23(11), 1251 - 3 {Late cryptococcal meningitis after liver transplantation}; Dumortier J et al.; We report a case of cryptococcal meningitis, eight years after liver transplantation for primary biliary cirrhosis . Detection of the cryptococcal antigen in serum and cerebrospinal fluid appears to be essential for initial diagnosis and follow-up . Oral fluconazole treatment alone can be effective, when given for a very long period to prevent relapse. Am J Med Sci, 1999 Dec, 318(6), 419 - 23 Hypercalcemia associated with infection by Cryptococcus neoformans and Coccidioides immitis; Ali MY et al.; BACKGROUND: Of the 13 reported cases of hypercalcemia associated with fungal infection, 1 was caused by Cryptococcus neoformans and probably mediated by increased levels of 1,25-dihydroxyvitamin D {1,25(OH)2D} . Eight others were associated with Coccidioides immitis, of which only 2 had measured 1,25(OH)2D levels; in both, they were diminished . We report a patient with human immunodeficiency virus infection and simultaneous C . immitis and C . neoformans pneumonia and C . immitis fungemia associated with hypercalcemia . METHODS: Consecutive measurements of serum total and ionized calcium, phosphorous, blood urea nitrogen, creatinine, 25(OH)D, 1,25(OH)2D, parathyroid hormone (PTH), parathyroid hormone-related protein (PTHrp) and albumin were performed over a period of 46 months . RESULTS: While the patient was hypercalcemic, intact serum PTH and PTHrp were undetectable, serum 25(OH)D levels were normal, and serum 1,25(OH)2D levels were in the high normal range . Successful treatment of the C . immitis and C . neoformans infections resulted in resolution of the hypercalcemia and increase of PTH and PTHrp to the normal range . CONCLUSION: In some patients with HIV infection, coincident hypercalcemia, and severe fungal infection, the responsible factor may be 1,25(OH)2D . Although total serum levels of this compound may not be frankly elevated, they are inappropriately high for the circumstances . Free 1,25(OH)2D levels should be determined in this situation. Rev Invest Clin, 1999 Sep-Oct, 51(5), 303 - 7 {Significance of intracranial hypertension management in cryptococcal meningitis in patients with acquired immunodeficiency syndrome . Report of 2 cases}; Nino Oberto S et al.; Two cases of cryptococcal meningitis and increased intracranial pressure in patients with acquired immunodeficiency are described . Both patients presented high intracranial pressure that persisted despite optimal antifungal treatment (amphotericin B, 5-flucytosine initially, and fluconazole posteriorly) . The elevated intracranial pressure produced headache, seizures, and reduced visual and auditory acuity . CAT scan demonstrated absence of ventricular dilatation or focal lesions . Both cases were treated with adequate antifungal therapy, as well as with repeated lumbar punctures and placement of a lumboperitoneal shunt due to the persistence of elevated intracranial pressure . One patient presented with unilateral loss of vision due to optic nerve atrophy . After one year of follow-up, one patient died due to progression of his disease, while the other is still alive and without evidence of neurological disease . Intracranial hypertension is a frequent clinical manifestation of cryptococcal meningitis in patients with acquired immunodeficiency syndrome (AIDS) that requires adequate diagnosis and management . Treatment should be directed towards the reduction of intracranial pressure though repeated lumbar punctures and, in some cases, with lumboperitoneal or ventricular-peritoneal shunts. Microbes Infect, 1999 Apr, 1(4), 293 - 301 Pathogenicity of Cryptococcus neoformans: virulence factors and immunological mechanisms; Rodrigues ML et al.; Cryptococcus neoformans is the causative agent of cryptococcosis and cryptococcal meningitis, which are serious pathological conditions affecting up to 10% of patients with AIDS . Mechanisms of pathogenicity of C . neoformans and the host defenses against this fungus are reviewed, incorporating recent data and perspectives. Chem Pharm Bull (Tokyo), 1999 Nov, 47(11), 1591 - 7 Tetranorditerpene lactones, potent antifungal antibiotics for human pathogenic yeasts, from a unique species of Oidiodendron; Hosoe T et al.; The culture filtrate of a fungus isolated from decaying Picea glauca wood and tentatively identified as Oidiodendron cf . truncatum showed strong antibiotic activity against the pathogenic yeast, Candida albicans . Four new tetranorditerpenoids, oidiodendrolides A (3), B (4), and C (5) and oidiodendronic acid (7) were isolated along with three known tetranorditerpenoids, LL-Z1271 alpha (= PR1387) (1), PR1388 (2), and acrostalidic acid (6), from rice fermented by the above fungus . The structures of oidiodendrolides A (3), B (4), and C (5) and oidiodendronic acid (7) were established on the basis of spectroscopic and chemical investigations . The antifungal activity of the above tetranorditerpenoids against the pathogenic yeasts, Candida albicans and Cryptococcus neoformans is discussed. Antimicrob Agents Chemother, 2000 Jan, 44(1), 226 - 9 In vitro activities of the new antifungal triazole SCH 56592 against common and emerging yeast pathogens; Barchiesi F et al.; A broth microdilution method performed in accordance with the National Committee for Clinical Laboratory Standards guidelines was used to compare the in vitro activity of the new antifungal triazole SCH 56592 (SCH) to that of fluconazole (FLC), itraconazole (ITC), and ketoconazole (KETO) against 257 clinical yeast isolates . They included 220 isolates belonging to 12 different species of Candida, 15 isolates each of Cryptococcus neoformans and Saccharomyces cerevisiae, and seven isolates of Rhodotorula rubra . The MICs of SCH at which 50% (MIC(50)) and 90% (MIC(90)) of the isolates were inhibited were 0.06 and 2.0 microg/ml, respectively . In general, SCH was considerably more active than FLC (MIC(50) and MIC(90) of 1.0 and 64 microg/ml, respectively) and slightly more active than either ITC (MIC(50) and MIC(90) of 0.25 and 2.0 microg/ml, respectively) and KETO (MIC(50) and MIC(90) of 0.125 and 4.0 microg/ml, respectively) . Our in vitro data suggest that SCH has significant potential for clinical development. Antimicrob Agents Chemother, 2000 Jan, 44(1), 143 - 9 Immunosuppressive and nonimmunosuppressive cyclosporine analogs are toxic to the opportunistic fungal pathogen Cryptococcus neoformans via cyclophilin-dependent inhibition of calcineurin; Cruz MC et al.; Cyclosporine (CsA) is an immunosuppressive and antimicrobial drug which, in complex with cyclophilin A, inhibits the protein phosphatase calcineurin . We recently found that Cryptococcus neoformans growth is resistant to CsA at 24 degrees C but sensitive at 37 degrees C and that calcineurin is required for growth at 37 degrees C and pathogenicity . Here CsA analogs were screened for toxicity against C . neoformans in vitro . In most cases, antifungal activity was correlated with cyclophilin A binding in vitro and inhibition of the mixed-lymphocyte reaction and interleukin 2 production in cell culture . Two unusual nonimmunosuppressive CsA derivatives, (gamma-OH) MeLeu(4)-Cs (211-810) and D-Sar (alpha-SMe)(3) Val(2)-DH-Cs (209-825), which are also toxic to C . neoformans were identified . These CsA analogs inhibit C . neoformans via fungal cyclophilin A and calcineurin homologs . Our findings identify calcineurin as a novel antifungal drug target and suggest nonimmunosuppressive CsA analogs warrant investigation as antifungal agents. Antimicrob Agents Chemother, 2000 Jan, 44(1), 57 - 62 In vitro activities of a new lipopeptide antifungal agent, FK463, against a variety of clinically important fungi; Tawara S et al.; The in vitro antifungal activity and spectrum of FK463 were compared with those of amphotericin B, fluconazole, and itraconazole by using a broth microdilution method specified by National Committee for Clinical Laboratory Standards document M27-A (National Committee for Clinical Laboratory Standards, Wayne, Pa., 1997) . FK463 exhibited broad-spectrum activity against clinically important pathogens including Candida species (MIC range, <==0.0039 to 2 microg/ml) and Aspergillus species (MIC range, <==0.0039 to 0.0313 microg/ml), and its MICs for such fungi were lower than those of the other antifungal agents tested . FK463 was also potently active against azole-resistant Candida albicans as well as azole-susceptible strains, and there was no cross-resistance with azoles . FK463 showed fungicidal activity against C . albicans, i.e., a 99% reduction in viability after a 24-h exposure at concentrations above 0.0156 microg/ml . The minimum fungicidal concentration (MFC) assays indicated that FK463 was fungicidal against most isolates of Candida species . In contrast, the MFCs of FK463 for A . fumigatus isolates were much higher than the MICs, indicating that its action is fungistatic against this species . FK463 had no activity against Cryptococcus neoformans, Trichosporon species, or Fusarium solani . Neither the test medium (kind and pH) nor the inoculum size greatly affected the MICs of FK463, while the addition of 4% human serum albumin increased the MICs for Candida species and A . fumigatus more than 32 times . Results from preclinical in vitro evaluations performed thus far indicate that FK463 should be a potent parenteral antifungal agent. FEBS Lett, 1999 Dec 10, 463(1-2), 58 - 62 SMAP-29: a potent antibacterial and antifungal peptide from sheep leukocytes; Skerlavaj B et al.; SMAP-29 is a cathelicidin-derived peptide deduced from sheep myeloid mRNA . The C-terminally amidated form of this peptide was chemically synthesized and shown to exert a potent antimicrobial activity . Antibiotic-resistant clinical isolates highly susceptible to this peptide include MRSA and VREF isolates, that are a major worldwide problem, and mucoid Pseudomonas aeruginosa associated with chronic respiratory inflammation in CF patients . In addition, SMAP-29 is also active against fungi, including Cryptococcus neoformans isolated from immunocompromised patients . SMAP-29 causes significant morphological alterations of the bacterial surfaces, as shown by scanning electron microscopy, and is also hemolytic against human, but not sheep erythrocytes . Its potent antimicrobial activity suggests that this peptide is an excellent candidate as a lead compound for the development of novel antiinfective agents. J Microbiol Immunol Infect, 1998 Jun, 31(2), 101 - 6 Bacteremia and fungemia in hematological and oncological children with neutropenic fever: two-year study in a medical center; Chiu HH et al.; A retrospective study of bacteremia in children with neutropenic fever admitted to a medical center in Taiwan from Jan . 1994 to Dec . 1995 was performed . There were in total 273 episodes of neutropenic fever during this period, but only 79 pathogens were isolated from blood specimens in 70 episodes . Klebsiella pneumoniae (27.8%), E . coli (10.1%), Staphylococcus aureus (10.1%) and Pseudomonas aeruginosa (7.6%) were the most common pathogens . All the isolates of S . aureus were methicillin sensitive . About half of K . pneumoniae (10/22) was multiple-drug resistant . There were seven infection-related mortality cases, three due to multiple-drug resistant K . pneumoniae, one due to S . aureus, one alpha-hemolytic streptococcus and two fungemia (Cryptococcus neoformans and Fusarium sp.) . Vancomycin is not necessary in initial empiric therapy of neutropenic fever, while cefazolin or oxacillin may be included in cases with central venous access device . Antibiotics to cover intestinal flora, especially K . pneumoniae, are paramount in our hospital. Ther Umsch, 1999 Nov, 56(11), 670 - 4 {CNS-infections in HIV patients}; Malinverni R et al.; Neurological manifestations are frequent in patients with AIDS . Many neurological disorders have disappeared with the advent of highly active antiretroviral combination therapies . We can speculate that some of these disorders may reappear in patients under antiretroviral therapy, possibly with different clinical manifestations and at a different stage during HIV-infection . We discuss the appearance of the most common neurological complications in relation to the CD4-cell count during HIV-infection . The most frequent causes of seizures and headache in HIV-infected patients are shown . We recommend a systematic diagnostic work-up in patients with headache, starting from 3 typical clinical situations: focal signs, convulsions or altered mental status; no focal signs, CD4-cells > 200 microliters, meningism; fever and/or meningism, no focal signs . The analysis of the cerebrospinal fluid by polymerase chain reaction is now a well established diagnostic method for investigating the most common CNS-infections in AIDS-patients . Neuroimaging (by MRI or CT-scan) is an additional, useful investigation . Cerebral toxoplasmosis, cryptococcosis, PML, encephalitis due to herpes-viruses and neurosyphilis are discussed. J Am Vet Med Assoc, 1999 Nov 1, 215(9), 1301 - 5 Endoscopic examination of the choanae in dogs and cats: 118 cases (1988-1998); Willard MD et al.; OBJECTIVE: To determine whether endoscopic examination of the choanae resulted in diagnosis of various diseases in dogs and cats with signs of respiratory tract disease . DESIGN: Retrospective study . ANIMALS: 91 dogs and 27 cats that had endoscopic examination of the choanae . PROCEDURE: Medical records were reviewed for endoscopy findings and results of examination of biopsy or cytologic specimens . RESULTS: 34 animals had neoplasia in the choanal region; in 26 animals, diagnosis was confirmed by evaluation of specimens obtained by endoscopy . Five dogs with neoplasia had an erroneous diagnosis of rhinitis made on the basis of evaluation of specimens obtained by endoscopy . Six dogs and 2 cats had foreign objects in the choanae; 7 foreign objects were removed endoscopically, whereas 1 required nasal flushing . Results of endoscopy and biopsy of the choanae provided diagnosis of cryptococcosis and aspergillosis, but did not aid in the diagnosis of pythiosis or nasal mites . CONCLUSIONS AND CLINICAL RELEVANCE: Endoscopic examination of the choanae may assist in rapid diagnosis of nasal neoplasms, foreign objects, and certain infectious organisms. Mol Cell Biol, 2000 Jan, 20(1), 352 - 62 The G-protein beta subunit GPB1 is required for mating and haploid fruiting in Cryptococcus neoformans; Wang P et al.; Cryptococcus neoformans is an opportunistic fungal pathogen with a defined sexual cycle . The gene encoding a heterotrimeric G-protein beta subunit, GPB1, was cloned and disrupted . gpb1 mutant strains are sterile, indicating a role for this gene in mating . GPB1 plays an active role in mediating responses to pheromones in early mating steps (conjugation tube formation and cell fusion) and signals via a mitogen-activated protein (MAP) kinase cascade in both MATalpha and MATa cells . The functions of GPB1 are distinct from those of the Galpha protein GPA1, which functions in a nutrient-sensing cyclic AMP (cAMP) pathway required for mating, virulence factor induction, and virulence . gpb1 mutant strains are also defective in monokaryotic fruiting in response to nitrogen starvation . We show that MATa cells stimulate monokaryotic fruiting of MATalpha cells, possibly in response to mating pheromone, which may serve to disperse cells and spores to locate mating partners . In summary, the Gbeta subunit GPB1 and the Galpha subunit GPA1 function in distinct signaling pathways: one (GPB1) senses pheromones and regulates mating and haploid fruiting via a MAP kinase cascade, and the other (GPA1) senses nutrients and regulates mating, virulence factors, and pathogenicity via a cAMP cascade. J Antimicrob Chemother, 1999 Dec, 44(6), 827 - 9 In-vitro and in-vivo activities of SCH56592 against Cryptococcus neoformans; Hossain MA et al.; The in-vitro and in-vivo activities of SCH56592, a triazole antifungal agent, against Cryptococcus neoformans were studied . MIC(90)s for 16 strains of C . neoformans measured by microdilution method (NCCLS M27-A) were 1 mg/L of SCH56592, 16 mg/L of fluconazole, 32 mg/L of flucytosine, and 0.5 mg/L of amphotericin B . In a murine model of pulmonary cryptococcosis, 10 mg/kg of SCH56592 was more effective than fluconazole . The fungal burden of the lung of animals treated with SCH56592 was significantly reduced (7.40 +/- 0.21 log(10) cfu/g), as compared with fluconazole (7.77 +/- 0.07 log(10) cfu/g) and control (7.79 +/- 0.1 log(10) cfu/g) (P < 0.01) . For C . neoformans-infected mice following 7 days treatment with 10 mg/kg of SCH56592 there was a higher concentration in lung (3.36 +/- 0.62 ng/ml) than in plasma (2.16 +/- 0.86 ng/mL), and this was maintained for 12 h after administration. Mycoses, 1999, 42(9-10), 543 - 8 Fungaemia survey: a 10-year experience in Bergamo, Italy; Farina C et al.; The authors analysed 10 years of experience of fungaemia at a Regional Italian Hospital, the Azienda Ospedaliera (A.O.) 'Ospedali Riuniti di Bergamo', Bergamo, Italy, from 1988 to 1997 . One hundred and sixty-eight cases were observed, with a global incidence corresponding to 3.43/10,000 in-patients . Median age was 38.5 years and mean age was 38.9 years (range: 0-94 years) . Female:male ratio was 1:1.75 . Fungaemia occurred 25.7 days (mean value) after admission to the hospital . Aetiology was: 134 Candida spp . (70%), 11 Cryptococcus neoformans (6.5%), seven Torulopsis inconspicua (4.1%), three Trichosporon beigelii (1.8%), one Hansenula anomala (0.6%); three Fusarium verticillioides (1.8%), three Geotrichum candidum (1.8%) and one Histoplasma capsulatum (0.6%) . Total mortality was 50.6%, and particularly related to Candida kefyr and Candida krusei, to Cr . neoformans and Fusarium spp. Antimicrob Agents Chemother, 1999 Dec, 43(12), 2862 - 8 Comparison of in vitro activities of camptothecin and nitidine derivatives against fungal and cancer cells; Del Poeta M et al.; The activities of a series of camptothecin and nitidine derivatives that might interact with topoisomerase I were compared against yeast and cancer cell lines . Our findings reveal that structural modifications to camptothecin derivatives have profound effects on the topoisomerase I-drug poison complex in cells . Although the water-soluble anticancer agents topotecan and irinotecan are less active than the original structure, camptothecin, other derivatives or analogs with substitutions that increase compound solubility have also increased antifungal activities . In fact, a water-soluble prodrug appears to penetrate into the cell and release its active form; the resulting effect in complex with Cryptococcus neoformans topoisomerase I is a fungicidal response and also potent antitumor activity . Some of the compounds that are not toxic to wild-type yeast cells are extremely toxic to the yeast cells when the C . neoformans topoisomerase I target is overexpressed . With the known antifungal mechanism of a camptothecin-topoisomerase I complex as a cellular poison, these findings indicate that drug entry may be extremely important for antifungal activity . Nitidine chloride exhibits antifungal activity against yeast cells through a mechanism(s) other than topoisomerase I and appears to be less active than camptothecin analogs against tumor cells . Finally, some camptothecin analogs exhibit synergistic antifungal activity against yeast cells in combination with amphotericin B in vitro . Our results suggest that camptothecin and/or nitidine derivatives can exhibit potent antifungal activity and that the activities of camptothecin derivatives with existing antifungal drugs may be synergistic against pathogenic fungi . These new compounds, which exhibit potent antitumor activities, will likely require further structural changes to find more selective activity against fungal versus mammalian cells to hold promise as a new class of antifungal agents. Microbios, 1999, 100(395), 27 - 40 Indigenous yeasts associated with two Vitis vinifera grape varieties cultured in southern Spain; De La Torre MJ et al.; The yeast microbiota present on the surface of grapes of two Vitis vinifera varieties, Pedro Ximenez and Tempranillo de Rioja, grown in the Montilla-Moriles region of southern Spain was identified . The changes between veraison and the physiological ripeness time during 3 years were monitored . Overall, the yeast microbiota isolated was of oxidative metabolism . Sporobolomyces roseus and Cryptococcus albidus species occurred at all physiological stages, in the two Vitis vinifera varieties, and the three seasons studied . On the other hand, Kloeckera apiculata was never detected and Saccharomyces cerevisiae was scarcely isolated, it was only present, testimonial, in Tempranillo de Rioja grapes during the 1992 vintage . The widest variety of yeast species was observed in the 1992 season, and in contrast, the lowest number of species in both varieties of Vitis was detected in the 1994 season. Genetics, 1999 Dec, 153(4), 1601 - 15 The STE12alpha homolog is required for haploid filamentation but largely dispensable for mating and virulence in Cryptococcus neoformans; Yue C et al.; Cryptococcus neoformans is a fungal pathogen that causes meningitis in immunocompromised hosts . The organism has a known sexual cycle, and strains of the MATalpha mating type are more virulent than isogenic MATa strains in mice, and they are more common in the environment and infected hosts . A C . neoformans homolog of the STE12 transcription factor that regulates mating, filamentation, and virulence in Saccharomyces cerevisiae and Candida albicans was identified previously, found to be encoded by a novel region of the MATalpha mating type locus, and shown to enhance filamentous growth when overexpressed . We have disrupted the C . neoformans STE12 gene in a pathogenic serotype A isolate . ste12 mutant strains exhibit a severe defect in filamentation and sporulation (haploid fruiting) in response to nitrogen starvation . In contrast, ste12 mutant strains have only modest mating defects and are fully virulent in two animal models compared to the STE12 wild-type strain . In genetic epistasis experiments, STE12 functions in a MAP kinase cascade to regulate fruiting, but not mating . Thus, the C . neoformans STE12alpha transcription factor homolog plays a specialized function in haploid fruiting, but it is dispensable or redundant for mating and virulence . The association of the MATalpha locus with virulence may involve additional genes, and other transcription factors that regulate mating and virulence remain to be identified. J Antibiot (Tokyo), 1999 Aug, 52(8), 695 - 9 Rhodopeptins (Mer-N1033), novel cyclic tetrapeptides with antifungal activity from Rhodococcus sp . I . Taxonomy, fermentation, isolation, physico-chemical properties and biological activities; Chiba H et al.; Five novel cyclic tetrapeptides, named rhodopeptin C1, C2, C3, C4 and B5, were isolated from a strain named Rhodococcus sp . Mer-N1033 . They are a novel type of cyclic tetrapeptide composed of a beta-amino acid and three usual alpha-amino acids . Rhodopeptins show high in vitro antifungal activity against Candida albicans and Cryptococcus neoformans, whereas they show no activity against bacteria. FEMS Immunol Med Microbiol, 1999 Dec, 26(3-4), 309 - 18 Cryptococcus neoformans and its cell wall components induce similar cytokine profiles in human peripheral blood mononuclear cells despite differences in structure; Walenkamp AM et al.; We studied the cytokine profile of peripheral blood mononuclear cells after stimulation with various cryptococcal strains or its purified cell wall components . After 3 h of stimulation, tumor necrosis factor (TNF) alpha levels were strongly increased, whereas interferon (IFN) gamma and interleukin (IL) 10 levels were increased only slightly, or not at all (respectively) . In contrast, after 18 h, TNF-alpha and IFN-gamma levels were (strongly) decreased, whereas the IL-10 levels were increased . The IL-1beta, IL-6 and IL-8 levels were equally high throughout the experiment . In order to establish which of the cryptococcal envelope components contributed most to the observed cytokine profile induced by whole cryptococci, glucuronoxylomannan, galactoxylomannan and mannoproteins were purified and partially characterized biochemically . All cryptococcal components elicited a similar cytokine pattern despite the differences in structure. Yeast, 1999 Nov, 15(15), 1657 - 67 Inositol synthesis and catabolism in Cryptococcus neoformans; Molina Y et al.; Cryptococcus neoformans is an opportunistic fungal pathogen that synthesizes and catabolizes inositol . This study demonstrates inositol synthesis from glucose-6-phosphate via inositol-1-phosphate synthase and catabolism to glucuronic acid via inositol oxygenase in this organism . These inositol synthetic and catabolic pathways are regulated in opposition; repressing conditions for one are inducing conditions for the other . An inositol-requiring strain was generated by UV mutagenesis . Without inositol, this mutant strain undergoes 'inositol-less' death, during which time the phosphatidylinositol composition of the membranes decreases without alteration of the proportion of other phospholipids . The mutation on this strain results in no detectable inositol synthetic activity but normal (wild-type) inositol catabolic activity . This inositol-requiring mutant strain reverted at a high frequency . Classical genetic experiments revealed that the majority of the reverting mutations are at second sites . Interestingly, the revertants exhibited unusual morphological phenotypes when deprived of inositol, while provision of inositol restored wild-type morphology . Inositol metabolism is clearly important for growth and development of C . neoformans and may be involved in this organism's mechanism for survival as both a saprophyte in soil and a parasite in humans . Appl Microbiol Biotechnol, 1999 Oct, 52(4), 495 - 501 Production of sophorolipids from whey . II . Product composition, surface active properties, cytotoxicity and stability against hydrolases by enzymatic treatment; Otto RT et al.; Sophorolipids, obtained by a two-stage process starting from deproteinized whey concentrate using Cryptococcus curvatus ATCC 20509 and Candida bombicola ATCC 22214, were compared to products from one-stage processes, using different lipidic compounds as substrates . Results showed that above all carbon source and not cultivation conditions had a distinct influence on the composition of the crude product mixture and therefore on the physicochemical and biological properties of the sophorolipids, such as, for example, surface activity, cytotoxicity and stability against hydrolases . The results were completed by corresponding data for purified mono- and diacetylated (17-hydroxyoctadecenoic)-1',4"-lactonized sophorolipids . Crude sophorolipid mixtures showed moderate to good surface active properties (SFTmin 39 mN m-1, CMC 130 mg l-1), water solubilities (2-3 g l-1) and low cytotoxicities (LC50 300-700 mg l-1) . In contrast, purified sophorolipids were more surface active (SFTmin 36 mN m-1, CMC 10 mg l-1), less water soluble (max . 70 mg l-1) and showed stronger cytotoxic effects (LC50 15 mg l-1) . Incubation of crude sophorolipid mixtures with different hydrolases demonstrated that treatment with commercially available lipases such as from Candida rugosa and Mucor miehei distinctly reduced the surface active properties of the sophorolipids, while treatment with porcine liver esterase and glycosidases had no effect. Rev Esp Quimioter, 1999 Jun, 12(2), 126 - 35 {Determination of the in vitro antifungal susceptibility of clinically important yeasts using the Sensititre system}; Carrillo-Munoz AJ et al.; Using Sensititre (AccuMed, USA) we studied the in vitro antifungal activity of amphotericin B, fluconazole, itraconazole, ketoconazole and 5-fluorocytosine against 250 clinical yeast isolates taken from different hospitals, including Candida (151 C . albicans, 15 C . krusei, 14 C . parapsilosis, 11 C . tropicalis, 10 C . glabrata, 4 C . guilliermondii, 3 C . rugosa, 2 C . viswanathii, 2 C . famata and 2 C . kefyr), Cryptococcus (32 C . neoformans and 1 C . laurentii), Trichosporon (2 isolates) and Rhodotorula rubra (1 isolate) . All the strains were susceptible to amphotericin B and showed an MIC <1 mg/l . The susceptibility of C . albicans (MIC(90) <256 mg/l), C . krusei (MIC(90) <64 mg/l), C . glabrata (MIC(90) <64 mg/l) and C . neoformans (MIC(90) 32 mg/l) to fluconazole was lower (14% isolates being resistant and 16.8% susceptible depending on the dose) . The largest number of strains resistant to itraconazole was observed in C . albicans and C . glabrata (17.2% resistant and 24% susceptible and susceptible depending on the dose, respectively) . Ketoconazole and 5-fluorocytosine were not effective in vitro against 12.8% and 2%, respectively, of all the isolates studied . Nine C . krusei and seven C . neoformans (12.9%) showed dose-dependent susceptibility to 5-fluorocytosine. Infect Immun, 1999 Dec, 67(12), 6314 - 20 Cytokine profiles of AIDS patients are similar to those of mice with disseminated Cryptococcus neoformans infection; Lortholary O et al.; Cryptococcosis is an hematogenously disseminated meningoencephalitis during which the relationship between the disease severity and the immune response remains unclear . We thus analyzed, by enzyme-linked immunosorbent assay, proinflammatory (tumor necrosis factor alpha {TNF-alpha} and interleukin-6 {IL-6}) and anti-inflammatory (IL-10) cytokine levels in plasma at the time of diagnosis in 51 AIDS patients with culture-proven cryptococcosis . We used a murine model to determine the correlation between cytokine levels and fungal burden in blood and tissues and the kinetics of the immune response and of the formation of cerebral lesions . In AIDS patients, plasma TNF-alpha and IL-10, but not IL-6, levels were significantly higher in the case of fungemia or disseminated infection than in their absence, whereas the presence of meningitis had no influence on these levels . In mice, none of these cytokines were detected within the first day after inoculation . Later on, TNF-alpha and IL-10, but not IL-6, levels in plasma correlated significantly with the fungal burden in the blood and spleen but not the brain . In the brain, cytokine levels were low compared to those in other compartments, and tissue lesions and a degree of infection similar to those observed in humans were seen, further suggesting the relevance of this experimental model . Thus, AIDS patients with cryptococcosis produce an immune response that reflects the dissemination but not the meningeal involvement . This murine model of disseminated cryptococcosis can be used to investigate the pathophysiology of cryptococcosis and new therapeutic approaches. AIDS, 1999 Nov 12, 13(16), 2197 - 207 HIV type 1 envelope glycoprotein gp120 induces development of a T helper type 2 response to Cryptococcus neoformans; Pietrella D et al.; OBJECTIVE: To analyse the contribution of HIV type 1 envelope glycoprotein gp120 to regulation of a T-cell response to Cryptococcus neoformans . DESIGN: Monocytes treated with recombinant gp120 and exposed to C . neoformans were used as antigen presenting cells (APC) in coculture with autologous T lymphocytes . METHODS: Costimulatory and major histocompatibility complex class II molecules were evaluated on APC by flow cytometry analysis . T-cell proliferation was determined as 3H thymidine incorporation . Cytokine production was analysed by enzyme-linked immunosorbent assay . RESULTS: gp120 had multiple effects on APC and the T-cell response including: (i) up-regulation of major histocompatibility complex class II antigens on the APC surface resulting from both redistribution of molecules from the intracellular pool and synthesis of new molecules; (ii) up-regulation of B7-2 molecules on the APC surface; (iii) altered T-cell proliferation; and (iv) promotion of interleukin-4 and inhibition of interferon-gamma synthesis and release . CONCLUSIONS: These data indicate that gp120 alters the normal T-cell response to C . neoformans, promoting a T-helper type 2 response . The altered T-cell response produced by gp120 may play an important role in the pathogenesis of cryptococcosis in the patient with AIDS. J Med Assoc Thai, 1999 Oct, 82(10), 991 - 9 Successful medical treatment of multiple cryptococcomas: report of a case and literature review; Arayawichanont A et al.; We report a 35-year-old man diagnosed as having CNS cryptococcosis with multiple cryptococcomas, presenting with headache, papilloedema and impaired mental function in a previously healthy man . Cerebrospinal fluid (CSF) examination revealed lymphocytic pleocytosis with low glucose level . Gram's stain, acid fast bacilli stain and Indian ink examination were all negative . CSF cryptococcal antigen was positive, however, several fungal cultures were negative . Early cranial CT scan showed focal cerebritis over the right temporal lobe while subsequent imaging studies showed multiple contrast-enhancing masses with severe surrounding brain oedema over bilateral frontoparietal areas . Brain biopsy showed cryptococcal granulomatous lesions . Treatment was successful with antifungal agents and steroids without surgical removal. J Formos Med Assoc, 1999 Sep, 98(9), 621 - 6 Pulmonary cryptococcosis: manifestations in the era of acquired immunodeficiency syndrome; Wu TT et al.; To examine the clinical manifestations, treatment, and outcome of pulmonary cryptococcosis, we reviewed the medical records of all patients treated for Cryptococcus neoformans infection at our hospital from January 1988 through September 1998 . Sixty-three patients were included in the analysis, 10 (16%) of whom had acquired immunodeficiency syndrome (AIDS) . Thirty-four of the 53 non-AIDS patients, including 19 men and 15 women had pulmonary cryptococcosis, including 31 with isolated pulmonary cryptococcosis and three with disseminated disease . Of the 10 AIDS patients, seven presented with disseminated cryptococcosis (including one patient with lung involvement) and one had isolated cryptococcal lung disease . The age (mean +/- SD) of the 34 non-AIDS patients with pulmonary cryptococcosis was 52.1 +/- 15.2 years (range, 19-75 yr) . Cough was the most common symptom (58%) . Diabetes mellitus (12%) and malignancy (12%) were two major underlying diseases . Nodules and masses were the predominant manifestations of pulmonary cryptococcosis in non-AIDS patients (79%) . The most frequently used diagnostic modality for pulmonary cryptococcosis was biopsy with/without aspiration under ultrasound guidance (56%) . Antifungal therapy (20/34) was the most common treatment for non-AIDS patients, followed by surgical resections with antifungal therapy (9), surgical resections alone (3), and no treatment (2) . Antifungal therapy and/or resection yielded excellent outcomes (total recovery, 27; improvement, 4) . Of the 18 patients who underwent lumbar puncture, only two had positive cerebrospinal fluid (CSF) cultures for C . neoformans, both had symptoms and signs of increased intracranial pressure . There was no clinical evidence of meningitis in the other 32 patients . Our findings indicate that pulmonary cryptococcosis in non-AIDS patients tends to be a more localized and benign process than in AIDS patients . Ultrasound-guided lung biopsy or aspiration is an effective tool for diagnosis . CSF examination may not be mandatory as an initial routine procedure for pulmonary cryptococcosis in non-AIDS patients. Dermatology, 1999, 199(2), 180 - 2 Cryptococcosis during systemic glucocorticosteroid treatment; Lauerma AI et al.; Cryptococcosis is an opportunistic infection caused by a fungus, Cryptococcus neoformans . It is usually seen in immunocompromised patients with AIDS, leukaemia, lymphoma, sarcoidosis or immunosuppressive treatments . We describe a patient who was treated with systemic glucocorticosteroids for 4 years because of lung sarcoidosis . During the last year of treatment, a papular eruption developed which later became ulcerative . In a histopathological examination of a skin biopsy, there was granulomatous inflammation, and the disease was treated as sarcoidosis without success . After 1 year's unsuccessful treatment, another skin biopsy and skin fungal culture revealed C . neoformans . Cryptococcal antigen was found in blood and cerebrospinal fluid, too . The patient was successfully treated first with an amphotericin-B-flucytosine combination and later with fluconazole. Cell Immunol, 1999 Oct 10, 197(1), 55 - 61 Interleukin-4 weakens host resistance to pulmonary and disseminated cryptococcal infection caused by combined treatment with interferon-gamma-inducing cytokines; Kawakami K et al.; We examined the role of interleukin (IL)-4 in host resistance against infection with Cryptococcus neoformans . First, we examined the effects of a neutralizing anti-IL-4 monoclonal antibody (mAb) on survival of mice infected intratracheally with this fungal pathogen . We also compared the number of live C . neoformans in lungs and brains of treated and untreated mice . Treatment with anti-IL-4 mAb significantly prolonged survival of infected mice and reduced the lung and brain burdens of C . neoformans, which was associated with increased production of IFN-gamma in lungs . In the next experiments, infected mice were treated with two IFN-gamma-inducing cytokines, IL-12 and IL-18, known to enhance protection against infection . We then evaluated the effect of such treatment on the number of live microorganisms and concentration of IL-4 in lungs . These two parameters showed a statistically significant relationship, suggesting a negative regulation of host protection by IL-4 . Finally, we examined the effects of IL-4 treatment and administration of neutralizing anti-IL-4 mAbs on host protection against C . neoformans and local production of IFN-gamma in lungs induced by treatment with IL-12/IL-18 . The former treatment suppressed host protection and reduced IFN-gamma production, while the latter produced the opposite effects . Our results indicated that IL-4 suppressed the host defense mechanisms against infection with C . neoformans potentiated by IFN-gamma-inducing cytokines probably through the suppression of local production of IFN-gamma . Biochem J, 1999 Nov 15, 344 Pt 1, 101 - 7 Binding energy and specificity in the catalytic mechanism of yeast aldose reductases; Nidetzky B et al.; Derivatives of d-xylose and d-glucose, in which the hydroxy groups at C-5, and C-5 and C-6 were replaced by fluorine, hydrogen and azide, were synthesized and used as substrates of the NAD(P)H-dependent aldehyde reduction catalysed by aldose reductases isolated from the yeasts Candida tenuis, C . intermedia and Cryptococcus flavus . Steady-state kinetic analysis showed that, in comparison with the parent aldoses, the derivatives were reduced with up to 3000-fold increased catalytic efficiencies (k(cat)/K(m)), reflecting apparent substrate binding constants (K(m)) decreased to as little as 1/250 and, for d-glucose derivatives, up to 5.5-fold increased maximum initial rates (k(cat)) . The effects on K(m) mirror the relative proportion of free aldehyde that is available in aqueous solution for binding to the binary complex enzyme-NAD(P)H . The effects on k(cat) reflect non-productive binding of the pyranose ring of sugars; this occurs preferentially with the NADPH-dependent enzymes . No transition-state stabilization energy seems to be derived from hydrogen-bonding interactions between enzyme-NAD(P)H and positions C-5 and C-6 of the aldose . In contrast, unfavourable interactions with the C-6 group are used together with non-productive binding to bring about specificity (6-10 kJ/mol) in a series of d-aldoses and to prevent the reaction with poor substrates such as d-glucose . Azide introduced at C-5 or C-6 destabilizes the transition state of reduction of the corresponding hydrogen-substituted aldoses by approx . 4-9 kJ/mol . The total transition state stabilization energy derived from hydrogen bonds between hydroxy groups of the substrate and enzyme-NAD(P)H is similar for all yeast aldose reductases (yALRs), at approx . 12-17 kJ/mol . Three out of four yALRs manage on only hydrophobic enzyme-substrate interactions to achieve optimal k(cat), whereas the NAD(P)H-dependent enzyme from C . intermedia requires additional, probably hydrogen-bonding, interactions with the substrate for efficient turnover. Prep Biochem Biotechnol, 1999 Nov, 29(4), 385 - 401 Preparation of novel conjugates involving immunomodulating peptidoglycan monomer; Tomasic J et al.; Peptidoglycan monomer, the disaccharide pentapeptide beta-D-Glcp-N-Ac-(1-->4)-D-Murp-N-Ac-L-Ala-D-mesoA2pm- (epsilonN H2)-D-Ala-D-Ala (PGM) is an immunomodulator . PGM and/or its derivative N-tert-butyloxycarbonyl-L-tyrosyl peptidoglycan monomer (Boc-Tyr-PGM) were coupled to two polysaccharides: the glucuronoxylomannan (GXM) from Cryptococcus neoformans, type B, solubilized by ultrasonic irradiation (MW 12-400 kDa) and to the dextran FP 70 (MW 70 kDa) . Both polysaccharides were activated by CNBr . Initially, unprotected PGM was coupled via its amino group to GXM . The reactions yielded 42%-52% of the conjugate, containing only 0.18%-0.31% of PGM . In another approach Boc-Tyr-PGM (having its amino group blocked) was reacted via its free carboxyl group . Both CNBr-activated polysaccharides were first coupled to adipic acid dihydrazide (ADH) and then subsequently coupled to Boc-Tyr-PGM . The dextran conjugate (approximately 80% yield ) contained 6.3% of Boc-Tyr-PGM . The isolation of GXM conjugate required several modifications and it was obtained in lower yield (approximately 30%) but contained 13.7% of Boc-Tyr-PGM . Both conjugates were water soluble and apyrogenic and suitable for further testing of biological activity. Antimicrob Agents Chemother, 1999 Nov, 43(11), 2663 - 70 Accumulation of 3-ketosteroids induced by itraconazole in azole-resistant clinical Candida albicans isolates; Marichal P et al.; The effects of itraconazole on ergosterol biosynthesis were investigated in a series of 16 matched clinical Candida albicans isolates which had been previously analyzed for mechanisms of resistance to azoles (D . Sanglard, K . Kuchler, F . Ischer, J . L . Pagani, M . Monod, and J . Bille, Antimicrob . Agents Chemother., 39:2378-2386, 1995) . Under control conditions, all isolates contained ergosterol as the predominant sterol, except two strains (C48 and C56) . In isolates C48 and C56, both less susceptible to azoles than their parent, C43, substantial concentrations (20 to 30%) of 14alpha-methyl-ergosta-8,24(28)-diene-3beta,6alpha-dio l (3, 6-diol) were found . Itraconazole treatment of C43 resulted in a dose-dependent inhibition of ergosterol biosynthesis (50% inhibitory concentration, 2 nM) and accumulation of 3,6-diol (up to 60% of the total sterols) together with eburicol, lanosterol, obtusifoliol, 14alpha-methyl-ergosta-5,7,22,24(28)-tetraene-3betaol, and 14alpha-methyl-fecosterol . In strains C48 and C56, no further increase of 3,6-diol was observed after exposure to itraconazole . Ergosterol synthesis was less sensitive to itraconazole inhibition, as was expected for these azole-resistant isolates which overexpress ATP-binding cassette transporter genes CDR1 and CDR2 . In addition to 3,6-diol, substantial amounts of obtusifolione were found after exposure to itraconazole . This toxic 3-ketosteroid was demonstrated previously to accumulate after itraconazole treatment in Cryptococcus neoformans and Histoplasma capsulatum but has not been reported in Candida isolates . Accumulation of obtusifolione correlated with nearly complete growth inhibition in these azole-resistant strains compared to that found in the susceptible parent strain, although the onset of growth inhibition only occurred at higher concentrations of itraconazole . ERG25 and ERG26 are the only genes assigned to the 4-demethylation process, of which the 3-ketoreductase is part . To verify whether mutations in these ERG25 genes contributed to obtusifolione accumulation, their nucleotide sequences were determined in all three related isolates . No mutations in ERG25 alleles of isolates C48 and C56 were found, suggesting that this gene is not involved in obtusifolione accumulation . The molecular basis for the accumulation of this sterol in these two strains remains to be established. Allergy, 1999 Oct, 54(10), 1067 - 73 Cross-reacting IgE and IgG antibodies to Pityrosporum ovale mannan and other yeasts in atopic dermatitis; Lintu P et al.; Atopic dermatitis (AD) patients often demonstrate positive skin prick test results and serum IgE antibodies to a range of different yeasts . This has been thought to be due to cross-reactivity . In this study, the cross-reactivity of IgE and IgG antibodies between mannan and crude antigens of Pityrosporum ovale, Candida albicans, and Saccharomyces cerevisiae and crude antigens of Cryptococcus albidus and Rhodotorula rubra was examined by RAST and ELISA inhibition with two serum pools of AD patients . We found cross-reacting IgE and IgG antibodies . In the IgE response, the main cross-reacting pattern was the mannan region, although inhibition could be achieved also with crude antigens of C . albicans, S . cerevisiae, and, to some extent, C . albidus . P . ovale was the most potent inhibitor of IgE-binding components, and against it the highest IgE antibody levels were detected in AD serum pools . In contrast, C . albicans was found to be the most important inducer of IgG antibodies, since the IgG level against P . ovale mannan in both AD serum pools was very low . Cross-reacting antibodies were also seen in ELISA inhibition with both crude and mannan antigens, but since the IgG antibody level of P . ovale mannan in AD serum pools was low, further studies are needed to confirm the IgG results. Postgrad Med J, 1999 May, 75(883), 297 - 8 Massive pleural effusions in cryptococcal meningitis; Wong CM et al.; Cryptococcal infection uncommonly presents with pulmonary manifestations and even more rarely so as massive bilateral effusions . Pleural involvement is usually associated with underlying pulmonary parenchymal lesions and is unusual while on antifungal therapy . We report a patient with cryptococcal meningitis who, while on intravenous 5-flucytosine and amphotericin B, developed life-threatening bilateral massive pleural effusions with evidence of spontaneous resolution, consistent with prior hypothesis of antigenic stimulation as the cause of pleural involvement. Infect Immun, 1999 Nov, 67(11), 6139 - 44 Isolation, characterization, cDNA cloning, and antimicrobial properties of two distinct subfamilies of alpha-defensins from rhesus macaque leukocytes; Tang YQ et al.; Experiments to isolate and characterize rhesus macaque myeloid alpha-defensins (RMADs) were conducted . Seven RMAD peptides were isolated and sequenced, and the cDNAs encoding six of these peptides and one other alpha-defensin from bone marrow were also characterized . Four of the RMADs were found to be highly similar to human neutrophil alpha-defensins HNP-1 to HNP-3, while the remaining four peptides were much more similar to human enteric alpha-defensin HD-5 . Two alpha-defensin pairs differed only by the presence or absence of an additional arginine at the amino termini of their mature peptides, indicative of alternate posttranslational processing . The primary translation products of RMAD-1 to -8 are 94- and 96-amino-acid prepropeptides that are highly similar to those of human alpha-defensins . Immunolocalization experiments revealed a granular cytoplasmic pattern in the cytoplasms of neutrophils, indistinguishable from the pattern observed after immunostaining of human myeloid alpha-defensins in polymorphonuclear leukocytes . Each of the purified peptides was tested for its in vitro activities against Staphylococcus aureus 502a, Listeria monocytogenes EGD, Escherichia coli ML35, and Cryptococcus neoformans 271A . Several of the peptides were microbicidal for the gram-positive bacteria and C . neoformans at defensin concentrations in the range of 2 to 5 microM . All of the peptides were bacteriostatic against E . coli, but none were bactericidal for this organism . This study is the first to characterize the sequences and activities of alpha-defensins from nonhuman primates, data that should aid in delineating the role of these peptides in rhesus macaque host defense. Infect Immun, 1999 Nov, 67(11), 6076 - 83 Phenotypic switching in Cryptococcus neoformans results in changes in cellular morphology and glucuronoxylomannan structure; Fries BC et al.; Cryptococcus neoformans strains exhibit variability in their capsular polysaccharide, cell morphology, karyotype, and virulence, but the relationship between these variables is poorly understood . A hypovirulent C . neoformans 24067A isolate, which usually produces smooth (SM) colony types, was found to undergo phenotypic switching and to produce wrinkled (WR) and pseudohyphal (PH) colony types at frequencies of approximately 10(-4) to 10(-5) when plated on Sabouraud agar . Cells from these colony types had large polysaccharide capsules and PH morphology, respectively . Scanning electron microscopy showed that different colony types were the result of altered cellular packing in the colony . Phenotypic switching was associated with quantitative and qualitative changes in capsular polysaccharide . Specifically, the glucuronoxylomannan (GXM) of the WR polysaccharide differed in the proportion of structural reporter groups and in increased xylose residue content linked at the 4 to 0 position . The relative virulence of the colony types was WR > PH > SM, as measured by CFU in rat lungs after intratracheal infection . Karyotype instability was observed in strain 24067A and involved primarily two chromosomes . Colonies with an alternative colony type exhibited more karyotype changes, which did not revert to the original karyotype in reverted colonies . In summary, this study revealed that phenotypic switching in C . neoformans (i) can produce WR colonies consisting of cells with either large capsule or PH morphology, (ii) is associated with production of structurally different GXM, (iii) is commonly associated with karyotype changes, (iv) can produce cells of PH morphology, and (v) can increase the virulence of a strain . Hence, phenotypic switching is an adaptive mechanism linked to virulence that can generate cell types with very different biological characteristics. Infect Immun, 1999 Nov, 67(11), 6034 - 9 Laccase protects Cryptococcus neoformans from antifungal activity of alveolar macrophages; Liu L et al.; While laccase of Cryptococcus neoformans is implicated in the virulence of the organism, our recent studies showing absence of melanin in the infected mouse brain has led us to a search for alternative roles for laccase in cryptococcosis . We investigated the role of laccase in protection of C . neoformans against murine alveolar macrophage (AM)-mediated antifungal activity by using a pair of congenic laccase-positive (2E-TUC) and laccase-deficient (2E-TU) strains . The laccase-positive cells with laccase derepression were more resistant to the antifungal activity of AM than a laccase-deficient strain ({28.9 +/- 1.2}% versus {40.2 +/- 2.6}% killing) . Addition of L-dopa to Cryptococcus to produce melanin in a laccase-positive strain resulted in a slight increase in protection of C . neoformans from the antifungal activity of macrophages ({25.4 +/- 3.4}% versus {28.9 +/- 1.2}% killing) . Recombinant cryptococcal laccase exhibited iron oxidase activity in converting Fe(II) to Fe(III) . Moreover, recombinant laccase inhibited killing of C . neoformans by hydroxyl radicals catalyzed by iron in a cell-free system . Addition of the hydroxyl radical scavenger mannitol or dimethyl sulfoxide to AMs prior to the introduction of cryptococcal cells decreased killing of both strains and reduced the difference in susceptibility between the laccase-positive and laccase-deficient strains . Furthermore, laccase-mediated protection from AM killing was inhibited by the addition of Fe(II), presumably by overcoming the effects of the iron oxidase activity of cryptococcal laccase . These results suggest that the iron oxidase activity of laccase may protect C . neoformans from macrophages by oxidation of phagosomal iron to Fe(III) with a resultant decrease in hydroxyl radical formation. Bioorg Med Chem, 1999 Sep, 7(9), 1933 - 40 Synthesis and antifungal activity of coumarins and angular furanocoumarins; Sardari S et al.; Angelicin, a naturally occurring furanocoumarin, that showed antifungal activity, was considered as a lead structure for a group of synthetic coumarins . Antifungal activities of the synthesized coumarins and angelicin derivatives were reported against Candida albicans, Cryptococcus neoformans, Saccharomyces cerevisiae and Aspergillus niger . Human cell line cytotoxicity of several coumarins was evaluated against KB cells . Angelicin and several potent antifungals showed to be non-toxic in this assay. Zentralbl Veterinarmed B,