Blood, 2004 Mar 15, 103(6), 2407 - 9 Epub 2003 Nov 20. Screening hepcidin for mutations in juvenile hemochromatosis: identification of a new mutation (C70R); Roetto A et al.; Juvenile or type 2 hemochromatosis (JH) is a genetic disease caused by increased intestinal iron absorption that leads to early massive iron overload . The main form of the disease is caused by mutations in a still unknown gene on chromosome 1q . Recently, we recognized a second type of JH with clinical features identical to the 1q-linked form, caused by mutations in the gene encoding hepcidin (HEPC) . Hepcidin is a hepatic antimicrobial-like peptide whose role in iron homeostasis was first defined in animal models; deficiency of hepcidin in mice leads to iron overload, whereas its hepatic overexpression in transgenic animals causes iron deficiency . To define the prevalence of HEPC mutations in JH we screened the HEPC gene for mutation in 21 unrelated JH subjects . We identified a new mutation (C70R), which affects 1 of the 8 conserved cysteines that form the disulfide bonds and are critical for the stability of the polypeptide. Farmaco, 2003 Dec, 58(12), 1235 - 42 Functionalized alkyl and aryl diselenides as antimicrobial and antiviral agents: synthesis and properties; Wojtowicz H et al.; The different dialkyl and diaryl diselenides with carbamoyl and sulfamoyl moieties 2, 3, 5 and other substituents in the ortho position of benzene ring 4, 7, 8 as well as derivatives of 1,2,4-benzoselenadiazine (6) were designed as antiviral and antimicrobial agents and synthesized . Some of them, particularly 8a and 8b, were found in the antiviral assay in vitro to be strong inhibitors of cytopathic activity encephalomyocarditis virus (EMCV) . The compound 4a and 8a were found to have a broad spectrum of acivity against bacteria, yeasts and pathogenic fungi in vitro. Fitoterapia, 2003 Dec, 74(7-8), 729 - 31 Antimicrobial activity and constituents of Coccoloba acrostichoides; Cota BB et al.; The ethanol extract and fractions from Coccoloba acrostichoides aerial parts were assayed for in vitro antimicrobial activity . The extract was active against the assayed bacteria while most of the fractions also inhibited fungal growth, especially the n-hexane and EtOAc fractions . The isolated beta-sitosterol and betulin were tested, being the last one active against Fusarium oxysporum. Fitoterapia, 2003 Dec, 74(7-8), 706 - 9 Antimicrobial and cytotoxicity evaluation of Buchholzia coriacea stem bark; Ajaiyeoba EO et al.; Fractions prepared from the methanol extract of Buchholzia coriacea stem bark exhibited a high concentration-dependent antibacterial and antifungal activity compared to the standard antibiotics, ampicillin and tioconazole . In the brine shrimp lethality (BSL) assay, the methanol extract was found to be non-toxic with an LC(50) of 1031 microg/ml . The two main compounds present in the most active fraction were isolated and identified as lupeol and beta-sitosterol. Fitoterapia, 2003 Dec, 74(7-8), 702 - 5 Antimicrobial activity of aqueous extracts and of berberine isolated from Berberis heterophylla; Freile ML et al.; The antimicrobial activity of Berberis heterophylla leaves, stems and root aqueous extracts was studied in vitro on Gram-positive and Gram-negative bacteria and fungi . The in vitro antifungal activity of berberine isolated from the same source against different Candida species was also investigated. Fitoterapia, 2003 Dec, 74(7-8), 695 - 8 Antimicrobial activity of extractives of Sarcocephalus coadunatus; Khan MR et al.; The methanolic extracts and the fractions (petrol, dichloromethane, ethyl acetate, butanol) obtained from the leaves, seeds, stem and root barks of Sarcocephalus coadunatus exhibited a high level of broad spectrum antibacterial activity . The activity was more pronounced in the dichloromethane, ethyl acetate and butanol fractions of the leaves; ethyl acetate and butanol fractions of the seeds; dichloromethane fractions of the stem bark and the ethyl acetate fractions of the root bark . None of the fractions showed any antifungal activity. Fitoterapia, 2003 Dec, 74(7-8), 692 - 4 Antimicrobial activity of Andrographis paniculata; Singha PK et al.; The antimicrobial activity of aqueous extract, andrographolides and arabinogalactan proteins from Andrographis paniculata were evaluated . The aqueous extract showed significant antimicrobial activity, which may be due to the combined effect of the isolated arabinogalactan proteins and andrographolides. Biotechniques, 2003 Nov, 35(5), 1060 - 4 Antibiotic-free bacterial strain selection using antisense peptide nucleic acid; Dryselius R et al.; Antibiotics are widely useful in medicine, agriculture, and industrial fermentations . However, increasing problems with resistant strains call for restrained use and alternative strategies . Antisense peptide nucleic acids (PNAs) show potent bactericidal effects when targeted against the essential Escherichia coli acpP gene . Aside from attractive antimicrobial therapeutic possibilities for such antisense PNAs, we considered that they could be used as a substitute for antibiotics in bacterial strain selection . Here, treatment of a mixture of E . coli wild-type cells and cells carrying a binding-site altered copy of acpP (acpP-1) with anti-acpP PNA completely killed wild-type cells within 2 h, whereas cells carrying acpP-1 proliferated . Furthermore, electrotransformation of E . coli cells with the plasmid carrying acpP-1 followed by PNA selection gave rise to only true transformants . Unlike previous antibiotic-free selection strategies, this procedure does not require special growth environments or special host strains . Also, the PNA-selected cells grow at a near normal rate . The results open possibilities to use antisense PNAs for strain selection and construction in research and industrial application. Biotechnol Appl Biochem . 2003 Nov 20; {Epub ahead of print} Recombinant antimicrobial peptides efficiently produced using novel cloning and purification processes; Metlitskaia L et al.; Endogenous antimicrobial peptides are ubiquitous components of animal and plant host defences . These peptides, usually cationic and amphipathic, kill target cells rapidly and are efficacious against antibiotic-resistant and clinically-relevant pathogens . A practical challenge in the development of cationic peptides as therapeutics is to meet the production requirements for large quantities of highly purified drug substance at competitive costs . While chemical peptide synthesis can be used to manufacture cationic peptides, we have developed cost-effective methods for recombinant production by expressing fusion proteins comprised of multiple copies of the peptides . The fusion proteins accumulate in E . coli inclusion bodies and constitute over 50% of the total cellular proteins . Active antimicrobial peptides are released by chemical reagents and purified by chromatography, combining both standard and novel approaches . Challenges of industrial scale manufacturing of therapeutics were considered in the development of this process. Int J Hyg Environ Health, 2003 Oct, 206(6), 465 - 72 State-of-the-art hand hygiene in community medicine; Kampf G; Hand hygiene becomes more important in community medicine not only since antibiotic resistant bacteria such as MRSA spread within the community . Hands may be colonized with transient microorganism in up to 75% . Among those transient pathogens S . aureus, C . difficile or the hepatitis C virus may be found . During patient care the number of microorganisms on the hands steadily increases . In addition hands may be contaminated with different kinds of germs even if only "clean" activities are carried out . Gloves may be worn but do not provide complete protection from contamination due to leaks . Therefore hands should always be treated after gloves are taken off . State-of-the-art treatment of hands is the hygienic hand disinfection with alcohol-based hand rubs . They are more effective, quicker to carry out, better tolerated by the skin, with a positive effect on compliance, and cost effective in comparison to antiseptic soaps based on chlorhexidine or triclosan and in comparison to normal non-medicated soaps . Healthy skin easily tolerates alcohol-based products from the beginning on . Only health care workers with an underlying irritative contact dermatitis which is often caused by bar or liquid antiseptic soaps may have difficulties to use alcohol-based products initially . In such a case treatment of the underlying skin condition is the way to go and not staying with a preparation which has caused the dermatitis . All this knowledge is now reflected in current guidelines on hand hygiene . Beside liquids alcohol-based gels can be used if they have an antimicrobial activity equal to alcohol-based liquid preparations . Hand hygiene remains the single most important tool to avoid cross transmission of microorganisms between patients . This state-of-the-art hand hygiene should also be emphasized more in community medicine . This review may help to go the first step into this direction. Cas Lek Cesk, 2003 Aug, 142(8), 483 - 6 {Treatment of Helicobacter pylori infections in gastric and duodenal ulcers}; Svestka T; Helicobacter pylori is an organism that is thought to be important in the pathophysiology of ulcer disease and gastritis . Eradication of the organism is useful in the treatment of infected patients . Efficacious regimens generally include an antisecretory agent combined with two antimicrobials . The main determinant of the overall cost of treatment is the eradication of H . pylori in the microorganism . Resistance to the commonly used antibiotics can occur but it can be usually overcome with regimen changes . It is important for care physicians to clearly understand when and how to test and how to select appropriate therapy for Helicobacter pylori infection. Cas Lek Cesk, 2003 Aug, 142(8), 465 - 9 {Hepcidin--a peptide regulating the quantity and distribution of iron in the body in healthy and disease states}; Vokurka M et al.; Iron is an essential element and its amount and balance must be precisely regulated . Iron intestinal absorption is essential for the iron balance; however, the precise mechanism of its regulation remains unknown . Antimicrobial peptide hepcidin, produced in the liver, is considered as a key regulator of iron absorption and kinetics in the organism . Its expression increases in response to the iron overload . Hepcidin decreases iron absorption in the duodenum and causes its sequestration in macrophages . Apart from the iron, inflammation increases hepcidin expression in the liver, and hepcidin is considered to be acute phase protein . Hepcidin is not only the physiological regulator of iron kinetics but is supposed to be a part of the pathogenetic mechanism of anaemia accompanying chronic diseases and its relationship to the hereditary hemochromatosis is also studied. Cell Mol Life Sci, 2003 Nov, 60(11), 2409 - 26 Pharmacologically active spider peptide toxins; Corzo G et al.; Advances in mass spectrometry and peptide biochemistry coupled to modern methods in electrophysiology have permitted the isolation and identification of numerous novel peptide toxins from animal venoms in recent years . These advances have also opened up the field of spider venom research, previously unexplored due to methodological limitations . Many peptide toxins from spider venoms share structural features, amino acid composition and consensus sequences that allow them to interact with related classes of cellular receptors . They have become increasingly useful agents for the study of voltage-sensitive and ligand-gated ion channels and the discrimination of their cellular subtypes . Spider peptide toxins have also been recognized as useful agents for their antimicrobial properties and the study of pore formation in cell membranes . Spider peptide toxins with nanomolar affinities for their receptors are thus promising pharmacological tools for understanding the physiological role of ion channels and as leads for the development of novel therapeutic agents and strategies for ion channel-related diseases . Their high insecticidal potency can also make them useful probes for the discovery of novel insecticide targets in the insect nervous system or for the development of genetically engineered microbial pesticides. FEMS Immunol Med Microbiol, 2003 Nov 28, 39(2), 155 - 61 Non-specific immunity-enhancing effects of tryptic casein hydrolysate versus Fermosorb for treatment/prophylaxis of newborn calf colibacillosis; Biziulevicius GA et al.; The effects of treatment/prophylaxis of newborn calf colibacillosis with tryptic casein hydrolysate (TCH), recently shown to be a novel type of antimicrobial acting through stimulation of the microbial autolytic system, versus an authorized veterinary drug, Fermosorb, were evaluated . Both products showed similar high therapeutic and prophylactic efficacies, but hematological indices and daily weight gain of cured/protected animals were better with TCH . The differences in hemoglobin and hematocrit levels, total protein, gamma-globulin and sulfhydryl group quantities, bactericidal and lysozyme activities as well as daily weight gain at the end of treatment/prophylaxis were statistically significant (P<0.05-0.000005) . Statistically significant differences (P<0.05-0.0005) in favor of TCH were also observed when bactericidal activity, total protein quantity of serum as well as daily weight gain of the animals were compared on the 90th day after birth . We conclude that TCH acts not only as an antimicrobial, but also as an immunostimulant (and growth promoter) . The immunostimulatory activity of TCH most probably derives from a synergistic action of bioactive peptides encrypted in the preparation itself and the cell wall fragments resulting from microbial autolysis induction. Curr Opin Infect Dis, 2003 Dec, 16(6), 547 - 51 Development of drugs for antimicrobial-resistant pathogens; Powers JH; PURPOSE OF REVIEW: Clinicians have noted an association between antimicrobial resistance and antimicrobial use since the introduction of these agents over 50 years ago . The problem of resistance becomes more pressing, however, when organisms acquire resistance mechanisms to multiple antimicrobial agents . Treatment options are limited for some multidrug-resistant organisms . Antimicrobial resistance is a driving force for the need for new antimicrobial agents, especially for these multidrug-resistant pathogens . At the same time, large pharmaceutical companies have indicated that they are devoting fewer resources to antimicrobial drug development . RECENT FINDINGS: This article will review initiatives by the US Food and Drug Administration to identify problem pathogens for which drug development is of most public health importance, and to streamline the drug development process for antimicrobial agents . This article will also touch upon initiatives by federal agencies to implement programs to educate clinicians and the public on the appropriate use of antimicrobial agents to preserve the usefulness of currently marketed drugs . SUMMARY: The most effective way to address the issues of antimicrobial resistance appears to be striking a balance between promoting new drug development and the prudent use of older agents to preserve the usefulness of currently marketed products. Curr Opin Infect Dis, 2003 Dec, 16(6), 515 - 9 Role of oral antimicrobial therapy in the management of osteomyelitis; Shuford JA et al.; PURPOSE OF REVIEW: Medical therapy of chronic osteomyelitis is largely based on experimental models, historical observational or non-randomized studies, and expert opinions . A minimum of 4-6 weeks of intravenous antimicrobial therapy targeting the causative organism, given in conjunction with surgery, has become the standard for chronic long-bone osteomyelitis in adults . Given the expense, inconvenience, and potential complications inherent to such a treatment program, alternative strategies including effective oral antimicrobial regimens are desirable . RECENT FINDINGS: Several oral antimicrobial agents have undergone evaluation for the treatment of acute and chronic osteomyelitis recently . These include fluoroquinolones, clindamycin, and linezolid . For the treatment of atypical causes of Gram-positive osteomyelitis, other oral therapies have been evaluated with reported success in small numbers of patients . SUMMARY: The standard of care for chronic osteomyelitis in adults remains intravenous antimicrobial therapy, in combination with surgery, for at least 4-6 weeks . Acute osteomyelitis in the pediatric population as well as osteomyelitis caused by atypical Gram-positive organisms and some Gram-negative organisms may be treated successfully with oral antibiotics . Some antimicrobials have equivalent concentration in serum whether administered orally or parenterally . When therapy with these antimicrobials is indicated, the oral route is preferred in compliant patients . As research continues in this area and as new drug formulations are developed, oral therapy may become an accepted alternative in additional selected patients. Proc Natl Acad Sci U S A, 2003 Nov 25, 100(24), 14281 - 6 Epub 2003 Nov 17. Delivery of antimicrobials into parasites; Samuel BU et al.; To eliminate apicomplexan parasites, inhibitory compounds must cross host cell, parasitophorous vacuole, and parasite membranes and cyst walls, making delivery challenging . Here, we show that short oligomers of arginine enter Toxoplasma gondii tachyzoites and encysted bradyzoites . Triclosan, which inhibits enoyl-ACP reductase (ENR), conjugated to arginine oligomers enters extracellular tachyzoites, host cells, tachyzoites inside parasitophorous vacuoles within host cells, extracellular bradyzoites, and bradyzoites within cysts . We identify, clone, and sequence T . gondii enr and produce and characterize enzymatically active, recombinant ENR . This enzyme has the requisite amino acids to bind triclosan . Triclosan released after conjugation to octaarginine via a readily hydrolyzable ester linkage inhibits ENR activity, tachyzoites in vitro, and tachyzoites in mice . Delivery of an inhibitor to a microorganism via conjugation to octaarginine provides an approach to transporting antimicrobials and other small molecules to sequestered parasites, a model system to characterize transport across multiple membrane barriers and structures, a widely applicable paradigm for treatment of active and encysted apicomplexan and other infections, and a generic proof of principle for a mechanism of medicine delivery. Int J Food Microbiol, 2003 Dec 31, 89(2-3), 163 - 70 Comparison of the activity of antifungal hexapeptides and the fungicides thiabendazole and imazalil against postharvest fungal pathogens; Lopez-Garcia B et al.; In this study, we evaluated the activity of short antimicrobial peptides against different fungal isolates that cause postharvest decay of fresh fruits . The previously identified hexapeptides PAF19, PAF26 and LfcinB4-9 inhibited the in vitro growth of isolates from Penicillium digitatum and P . italicum, and from Alternaria and Geotrichum genera, being no active against Rhizopus, Mucor and Aspergillus . The results extend our previous observations on the specific and distinct activity profiles of this class of antifungal peptides . In addition, peptide activities were compared with that of two fungicides used for citrus fruit preservation, thiabendazole (TBZ) and imazalil (IMZ) . We observed a lack of correlation between peptide and fungicide sensitivity among different species . Importantly, P . digitatum and P . italicum isolates resistant to fungicides were susceptible to peptides and our data suggest that common multiple drug resistance mechanisms are not active against this class of peptides . The in vitro peptide inhibition was correlated with a retard of the decay caused by Penicillium on citrus fruits, and this effect was comparable for both fungicide-resistant and -sensitive isolates . Comparison of PAF26 and TBZ in vitro minimum inhibitory concentration (MIC) values and their in vivo effect on citrus decay indicated that PAF26 performed in vivo better than TBZ. Int J Food Microbiol, 2003 Dec 31, 89(2-3), 125 - 38 Combining nonthermal technologies to control foodborne microorganisms; Ross AI et al.; Novel nonthermal processes, such as high hydrostatic pressure (HHP), pulsed electric fields (PEFs), ionizing radiation and ultrasonication, are able to inactivate microorganisms at ambient or sublethal temperatures . Many of these processes require very high treatment intensities, however, to achieve adequate microbial destruction in low-acid foods . Combining nonthermal processes with conventional preservation methods enhances their antimicrobial effect so that lower process intensities can be used . Combining two or more nonthermal processes can also enhance microbial inactivation and allow the use of lower individual treatment intensities . For conventional preservation treatments, optimal microbial control is achieved through the hurdle concept, with synergistic effects resulting from different components of the microbial cell being targeted simultaneously . The mechanisms of inactivation by nonthermal processes are still unclear; thus, the bases of synergistic combinations remain speculative . This paper reviews literature on the antimicrobial efficiencies of nonthermal processes combined with conventional and novel nonthermal technologies . Where possible, the proposed mechanisms of synergy is mentioned. Biochem Biophys Res Commun, 2003 Nov 28, 311(4), 853 - 63 AML-1, PU.1, and Sp3 regulate expression of human bactericidal/permeability-increasing protein; Lennartsson A et al.; Bactericidal/permeability-increasing protein (BPI) is an antimicrobial protein in neutrophils, stored in azurophil granules . Expression of BPI is absent in neutrophils of newborns and patients with secondary granule deficiency (SGD), possibly contributing to dysfunction of neutrophils . We report two alternative transcription start sites at 52 and 22bp upstream of the translation start . A proximal 222bp promoter conferring expression in myeloid cells was identified, and critical cis-acting sites for myeloid expression were contained within the 159bp upstream of translation start . Within this region, direct binding and transactivation by AML-1, PU.1, and Sp3 were demonstrated, as judged by electrophoretic mobility shift analysis . Moreover, transient transfections of C/EBPalpha or C/EBPepsilon to HeLa cells resulted in increased promoter activity, indicating a direct or indirect role for C/EBP . In conclusion, we provide evidence for AML-1, PU.1, and Sp3 cooperatively and directly mediating BPI-expression during myeloid differentiation. J Feline Med Surg, 2003 Dec, 5(6), 305 - 11 Efficacy of azithromycin for the treatment of feline chlamydophilosis; Owen WM et al.; The current recommended treatment for feline chlamydophilosis involves daily oral administration of antimicrobials to all cats within an affected group for a prolonged period of time (4-6 weeks) . Not surprisingly, owner compliance can be poor resulting in apparent treatment failure . Recent anecdotal evidence, supported by its efficacy in the treatment of Chlamydia trachomatis infection in humans, has suggested that azithromycin may offer an alternative by allowing less frequent dosing for a shorter duration . A clinical trial was designed to evaluate the efficacy of azithromycin for the treatment of chlamydia (Chlamydophila felis) infection in cats . Whilst azithromycin, given at 10-15 mg/kg daily for 3 days and then twice weekly, provided a similar, rapid resolution of clinical signs and negative isolation scores as doxycycline, C felis was re-isolated in four out of the five cats treated . Furthermore, even daily administration of azithromycin to chronically infected cats was ineffective in clearing infection . The azithromycin protocols used here were therefore found to be unsuccessful in eliminating the carriage of this strain of C felis. J Hosp Infect, 2003 Nov, 55 Suppl 1, 1 - 12 Appropriate antimicrobial treatment in nosocomial infections-the clinical challenges; Masterton R et al.; Resistance to antimicrobial agents is emerging in a wide variety of pathogens, particularly those that cause nosocomial infections . As a consequence of this increasing resistance, morbidity and mortality in nosocomial infections is also increasing . It is therefore critical to treat nosocomial infections appropriately by starting antimicrobial treatment early in the course of infection, using the correct agent, at the most appropriate dose, and for an adequate duration . Indeed, early 'appropriate' antibiotic prescribing has been shown significantly to reduce mortality, length of intensive care unit and hospital stay and overall costs.Early use of the correct antibiotic at the appropriate dose and for an adequate duration are key to initial appropriate antibiotic prescribing . Choosing the right antibiotic depends mainly on the likely pathogen(s) and the expected local susceptibility patterns . Selection of appropriate antimicrobial therapy requires a thorough understanding of the likely microbial cause of the infection, including local susceptibility patterns, as well as the properties of the antimicrobials available for treating these infections, namely spectrum of activity and potency (including activity versus known resistance mechanisms), pharmacokinetic profile and tolerability and safety . This review, based on a series of presentations at the 5th International Conference of the Hospital Infection Society (Edinburgh, 2002) examines the importance of appropriate antimicrobial therapy in nosocomial infections, and provides guidance on how to achieve this. Eur J Biochem, 2003 Nov, 270(22), 4478 - 87 Bilayer localization of membrane-active peptides studied in biomimetic vesicles by visible and fluorescence spectroscopies; Sheynis T et al.; Depth of bilayer penetration and effects on lipid mobility conferred by the membrane-active peptides magainin, melittin, and a hydrophobic helical sequence KKA(LA)7KK (denoted KAL), were investigated by colorimetric and time-resolved fluorescence techniques in biomimetic phospholipid/poly(diacetylene) vesicles . The experiments demonstrated that the extent of bilayer permeation and peptide localization within the membrane was dependent upon the bilayer composition, and that distinct dynamic modifications were induced by each peptide within the head-group environment of the phospholipids . Solvent relaxation, fluorescence correlation spectroscopy and fluorescence quenching analyses, employing probes at different locations within the bilayer, showed that magainin and melittin inserted close to the glycerol residues in bilayers incorporating negatively charged phospholipids, but predominant association at the lipid-water interface occurred in bilayers containing zwitterionic phospholipids . The fluorescence and colorimetric analyses also exposed the different permeation properties and distinct dynamic influence of the peptides: magainin exhibited the most pronounced interfacial attachment onto the vesicles, melittin penetrated more into the bilayers, while the KAL peptide inserted deepest into the hydrophobic core of the lipid assemblies . The solvent relaxation results suggest that decreasing the lipid fluidity might be an important initial factor contributing to the membrane activity of antimicrobial peptides. Biochemistry, 2003 Nov 25, 42(46), 13725 - 34 Immobilization and aggregation of the antimicrobial peptide protegrin-1 in lipid bilayers investigated by solid-state NMR; Buffy JJ et al.; The dynamics and aggregation of a beta-sheet antimicrobial peptide, protegrin-1 (PG-1), are investigated using solid-state NMR spectroscopy . Chemical shift anisotropies of F12 and V16 carbonyl carbons are uniaxially averaged in 1,2-dilauryl-sn-glycero-3-phosphatidylcholine (DLPC) bilayers but approach rigid-limit values in the thicker 1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphatidylcholine (POPC) bilayers . The Calpha-Halpha dipolar coupling of L5 is scaled by a factor of 0.16 in DLPC bilayers but has a near-unity order parameter of 0.96 in POPC bilayers . The larger couplings of PG-1 in POPC bilayers indicate immobilization of the peptide, suggesting that PG-1 forms oligomeric aggregates at the biologically relevant bilayer thickness . Exchange NMR experiments on F12 (13)CO-labeled PG-1 show that the peptide undergoes slow reorientation with a correlation time of 0.7 +/- 0.2 s in POPC bilayers . This long correlation time suggests that in addition to aggregation, geometric constraints in the membrane may also contribute to PG-1 immobilization . The PG-1 aggregates contact both the surface and the hydrophobic center of the POPC bilayer, as determined by (1)H spin-diffusion measurements . Thus, solid-state NMR provides a wide range of information about the molecular details of membrane peptide immobilization and aggregation in lipid bilayers. Biochemistry, 2003 Nov 25, 42(46), 13613 - 24 SpaC and NisC, the cyclases involved in subtilin and nisin biosynthesis, are zinc proteins; Okeley NM et al.; Lantibiotics are peptide-derived antimicrobial agents that are ribosomally synthesized and posttranslationally modified by a multienzyme complex to their biologically active forms . Nisin has attracted much attention recently due to its novel mechanism of action including specific binding to the bacterial cell wall precursor lipid II, followed by membrane permeabilization . Nisin has been commercially used as a food preservative, while other lantibiotics show promising activity against bacterial infections . The posttranslational modifications are believed to be carried out by a multienzyme complex . At present the enzymes catalyzing the formation of the lantibiotic signature structural motifs, dehydroalanine (Dha), dehydrobutyrine (Dhb), lanthionine (Ln), and methyllanthionine (MeLn), are poorly characterized . In an effort to gain insight into the mechanism by which lantibiotics are biosynthesized, the cyclase enzymes involved in the synthesis of nisin and subtilin (NisC and SpaC, respectively) have been cloned, expressed, and purified . Both proteins exist as monomers in solution and contain a stoichiometric zinc atom . EXAFS data on SpaC and a C349A mutant are in line with two cysteine ligands to the metal in the wild-type enzyme with possibly two additional histidines . The two cysteine ligands are likely Cys303 and Cys349 on the basis of sequence alignments and EXAFS data . The metal may function to activate the cysteine thiol of the peptide substrate toward intramolecular Michael addition to the dehydroalanine and dehydrobutyrine residues in the peptide. J Am Vet Med Assoc, 2003 Nov 1, 223(9), 1306 - 10, 1280-1 Concurrent bartonellosis and babesiosis in a dog with persistent thrombocytopenia; Tuttle AD et al.; A 12-year-old castrated male West Highland White Terrier was referred because of recurrent episodes of collapsing . The dog was mildly anemic and severely thrombocytopenic and had high serum alanine aminotransferase activity . Infection with Bartonella vinsonii (berkhoffii) was initially diagnosed on the basis of serologic testing . Despite treatment with a series of antimicrobials and prolonged use of immunosuppressive drugs, thrombocytopenia persisted . After 5 months of treatment, Babesia canis organisms were seen during examination of a direct blood smear . The dog was treated with imidocarb dipropionate for babesiosis, after which thrombocytopenia resolved, and administration of immunosuppressive drugs was discontinued . Retrospective review of blood smears failed to identify organisms; however, polymerase chain reaction (PCR) analysis of multiple stored blood samples obtained during the 5-month period of persistent thrombocytopenia identified DNA of B . canis vogeli . Babesiosis may cause persistent, unexplained thrombocytopenia in dogs that are not anemic . A PCR assay can facilitate a diagnosis of babesiosis when organisms are not evident or when serologic testing fails to detect Babesia-specific antibodies. Dig Liver Dis, 2003 Oct, 35(10), 706 - 10 Use of bovine lactoferrin for Helicobacter pylori eradication; Di Mario F et al.; BACKGROUND: One-week triple therapy is the most frequently recommended treatment for Helicobacter pylori infection . Eradication rate is satisfactory, nevertheless is advisable to look for more effective therapies . AIM: To test the efficacy of a standard triple therapy plus bovine lactoferrin in the eradication of H . pylori infection . PATIENTS AND METHODS: One hundred and fifty consecutive H . pylori positive patients, suffering from dyspeptic symptoms were recruited in a 7-day triple therapy open randomised single centre study with rabeprazole, clarithromycin, tinidazole, bovine lactoferrin (group A) or rabeprazole, clarithromycin, tinidazole (group B), or a 10-day therapy with rabeprazole, clarithromycin, tinidazole (group C) . H . pylori status was assessed 8 weeks after the end of the treatment by means of a 13C-urea breath test or a H . pylori stool antigen-test . RESULTS: Eradication rates (intention to treat/per protocol) were: group A (92.2/95.9%), group B (71.2/72.5%) and group C (70.2/75%) . The efficacy of triple therapy added with lactoferrin was significantly higher than other two regimens (p=0.01, intention to treat analysis; p=0.005, per protocol analysis) . CONCLUSION: These results suggest that lactoferrin tested in the present study was effective in curing H . pylori and could be a new agent to assist the antimicrobials in the eradication of the bacterium. Pharmacotherapy, 2003 Nov, 23(11), 1497 - 507 Chemical and microbiologic aspects of penems, a distinct class of beta-lactams: focus on faropenem; Hamilton-Miller JM; Many beta-lactam antimicrobials were developed between the 1960s and 1980s, with continuing development driven by the emergence of microbial resistance . Penems form a discrete class of beta-lactams that comprises structural hybrids of penicillins (penams) and cephalosporins (cephems) . The chemistry and microbiology of the representative penems MEN 10700, ritipenem, CGP 31608, sulopenem, BRL 42715, and faropenem are reviewed . Particular emphasis is placed on faropenem, which is in late clinical development. Pharmacotherapy, 2003 Nov, 23(11), 1486 - 96 Management of severe sepsis: integration of multiple pharmacologic interventions; Micek ST et al.; Severe sepsis is an infection-induced process that often promotes organ dysfunction and death in up to 50% of afflicted patients . Clinical advances that improve patient survival include early goal-directed volume resuscitation, broad-spectrum empiric antimicrobial therapy with deescalation strategies, therapy with drotrecogin alfa (activated), glucocorticoid replacement in patients with adrenal insufficiency, and tight control of blood glucose levels . The challenge for critical care practitioners is to integrate the many pharmacologic and supportive interventions required for optimal care of these patients. Scand J Infect Dis, 2003, 35(9), 670 - 6 Cathelicidins and innate defense against invasive bacterial infection; Nizet V et al.; Cathelicidins are small cationic peptides that possess broad-spectrum antimicrobial activity . These gene-encoded 'natural antibiotics' are produced by several mammalian species on epithelial surfaces and within the granules of phagocytic cells . Since their discovery over a decade ago, cathelicidins have been speculated to function within the innate immune system, contributing to a first line of host defense against an array of microorganisms . Consequently, cathelicidins have captured the interest of basic investigators in the diverse fields of cell biology, immunology, protein chemistry and microbiology . A burgeoning body of experimental research now appears to confirm and extend the biological significance of these fascinating molecules . This article reviews the latest advances in the knowledge of cathelicidin antimicrobial peptides, with particular emphasis on their role in defense against invasive bacterial infection and associations with human disease conditions. Scand J Infect Dis, 2003, 35(9), 573 - 6 Macrophage migration inhibitory factor and host innate immune responses to microbes; Calandra T; Among innate immune cells, macrophages play an essential role in the sensing and elimination of invasive microorganisms . Binding of microbial products to pathogen-recognition receptors stimulates macrophages to release cytokines and other effector molecules that orchestrate the host innate and adaptive immune responses . Recently, the protein known as macrophage migration inhibitory factor (MIF) has emerged as a pivotal mediator of innate immunity . First identified as a T-cell cytokine, MIF was rediscovered as a protein released by pituitary cells after exposure to endotoxin {lipopolysaccharide (LPS)} or bacteria and in response to stress . Monocytes, macrophages and lymphocytes constitutively express MIF, which is rapidly released after stimulation with bacterial endotoxins and exotoxins, and cytokines . MIF induces powerful proinflammatory biological responses and has been shown to be an important effector molecule of septic shock . High levels of MIF have been detected in the circulation of patients with severe sepsis and septic shock . Inhibition of MIF activity with neutralizing anti-MIF antibodies or deletion of the Mif gene led to a marked reduction in cytokine production and protected mice from lethal bacterial sepsis and toxic shock induced by Gram-negative endotoxin or Gram-positive exotoxins . Investigations into the mechanisms whereby MIF modulates innate immune responses to endotoxin and Gram-negative bacteria have shown that MIF up-regulates the expression of Toll-like receptor 4 (TLR4), the signal-transducing molecule of the LPS receptor complex . Thus, MIF enables cells, such as the macrophage, that are at the forefront of the host antimicrobial defences, to sense promptly the presence of invading Gram-negative bacteria and mount an innate immune response . Given that it is a pivotal regulator of innate immune responses to bacterial infections, MIF appears to be a perfect target for novel therapeutic interventions in patients with severe sepsis. Am J Health Syst Pharm, 2003 Nov 1, 60(21), 2229 - 32 Neutropenia in patients receiving long-term cefepime therapy for osteomyelitis; Wong BB et al.; The frequency of neutropenia in patients receiving long-term cefepime therapy for osteomyelitis compared with that in patients receiving other antimicrobials was studied . A comparative case review was conducted of home infusion patients receiving cefepime and patients receiving other antimicrobials for osteomyelitis . All courses of antimicrobial therapy for osteomyelitis between January 2001 and December 2002 were evaluated . The duration of prescribed therapy was approximately six weeks . Weekly laboratory tests included complete blood counts with differential . A total of 134 courses of antimicrobial therapy were reviewed (13 courses of cefepime therapy in 12 patients and 121 courses of therapy with other i.v . antimicrobials in 120 patients) . Eight (62%) of the cefepime courses resulted in neutropenia, compared with none in the courses of other antimicrobials . Neutropenia was detected after 17-30 days of cefepime therapy . Blood counts returned to normal within one week of cefepime discontinuation . Eight of 13 courses of extended therapy with i.v . cefepime for osteomyelitis resulted in neutropenia, compared with none of 121 courses of other antimicrobials . Clinicians should exercise extreme caution when prescribing cefepime for longer than 14 days. Helicobacter, 2003, 8 Suppl 1, 53 - 60 Treatment of Helicobacter pylori infection; Perri F et al.; Review of the recently published data on Helicobacter pylori management highlights various interesting aspects . Current H . pylori eradication guidelines generally suggest a noninvasive 'test and treat' strategy for all dyspeptic patients with certain age limits depending on the local gastric neoplasia risk . According to the 'Maastricht 2-2000 Consensus Report' treatment should be thought of as a 'package' considering first- and second-line eradication therapies together . Various centres have published their results using novel antimicrobial formulations and 'rescue' and 'sequential' therapies . Review suggests that care at the specialist level remains a challenge and guidelines are deficient particularly as regards the selection and duration of eradication therapies . Results indicate that differences for CYP2C19 genotype and the selection of proton pump inhibitors have no significant role in determining eradication rates whereas antibiotic resistance and socio-economic factors play a variable role according to different geographical areas . Compliance remains an important factor in determining clinical outcome at the primary and secondary levels worldwide. Curr Opin Ophthalmol, 2003 Dec, 14(6), 413 - 9 Retinal vasculitis; Walton RC et al.; Retinal vasculitis represents a group of diseases characterized by inflammation affecting the retinal vasculature . It is an uncommon disorder that may occur as an isolated disease or more commonly in association with other ocular diseases or a variety of systemic diseases . With a wide variety of disease associations, a search for an underlying etiology should be undertaken based on a meticulous history, review of systems, and physical examination . The laboratory evaluation of patients with retinal vasculitis is an essential component of the work-up to facilitate detection of any underlying disease or to establish a limited differential diagnosis . The management of infectious causes of retinal vasculitis consists of antimicrobial therapy while noninfectious retinal vasculitis is managed with corticosteroids and/or immunosuppressive agents . Because retinal vasculitis is an uncommon disease, there are only a limited number of publications over the past year related to this topic. Pediatr Infect Dis J, 2003 Nov, 22(11), 996 - 1002 Role of antimicrobial applications to the umbilical cord in neonates to prevent bacterial colonization and infection: a review of the evidence; Mullany LC et al.; In developing countries umbilical cord infections constitute a major cause of neonatal morbidity and pose significant risk for mortality, whereas outbreaks of cord infections continue to occur in developed country nurseries . Cord infections in developing countries can be prevented through increasing access to tetanus toxoid immunization during pregnancy, promoting clean cord care and reducing harmful cord applications and behaviors . Interventions introduced in both developed and developing countries to reduce exposure of the cord to infectious pathogens include clean cord cutting, hand-washing before and after handling the baby, bathing of the infant with antimicrobial agents and application of antimicrobials to the cord . Despite the importance of umbilical cord care, both traditionally and medically, there have been few randomized trials investigating the impact of different cord care regimens on rates of local or systemic infections, particularly in developing countries.This review examines available data on umbilical cord care, with a particular focus on those comparing rates of bacterial colonization and/or rates of cord infection among neonates receiving different umbilical cord care regimens . Although most investigators agree that topical antimicrobials reduce bacterial colonization of the cord, a firm relationship between colonization and infection has not been established . Further research in developed countries, including follow-up beyond hospital discharge, is required before advising on "best cord care practices." The paucity of published reports from developing countries indicates the need to investigate the impact of antimicrobial applications on cord and systemic infections in a community-based, prospective manner. Microbes Infect, 2003 Nov, 5(14), 1317 - 27 Neutrophil granules and secretory vesicles in inflammation; Faurschou M et al.; The neutrophil is a major effector cell of innate immunity . Exocytosis of granules and secretory vesicles plays a pivotal role in most neutrophil functions from early activation to the destruction of phagocytosed microorganisms . Neutrophil granules contain a multitude of antimicrobial and potentially cytotoxic substances that are delivered to the phagosome or to the exterior of the cell following degranulation . This review summarises current knowledge of granule biology and highlights the effects of neutrophil degranulation in the acute inflammatory response. Microbes Infect, 2003 Nov, 5(14), 1293 - 8 Neutrophil cell signaling in infection: role of phosphatidylinositide 3-kinase; Moraes TJ et al.; Neutrophils play a pivotal role in the innate immune response to microbial pathogens . They are uniquely suited to this role by virtue of specialized antimicrobial capabilities that include the capacity to sense minute amounts of microbial products and inflammatory mediators, to move to the site of infection, and finally to bind, internalize and kill the pathogens . To optimize host defense capabilities while minimizing damage to host tissues ('collateral damage'), these microbicidal responses must be tightly regulated . Additionally, neutrophils clear inflammatory debris, a process that is necessary for restoration of the native architecture and function of the tissue . This review highlights some recent advances in our knowledge of cell signaling as it pertains to neutrophil function, with specific emphasis on the role of the phosphatidylinositide 3-kinase in antimicrobial function. Bioorg Chem, 2003 Dec, 31(6), 425 - 36 Cathelicidin family of antimicrobial peptides: proteolytic processing and protease resistance; Shinnar AE et al.; Cathelicidins are a gene family of antimicrobial peptides produced as inactive precursors . Signal peptidase removes the N-terminal signal sequence, while peptidylglycine alpha-amidating monooxygenase often amidates and cleaves the C-terminal region . Removal of the cathelin domain liberates the active antimicrobial peptide . For mammalian sequences, this cleavage usually occurs through the action of elastase, but other tissue-specific processing enzymes may also operate . Once released, these bioactive peptides are susceptible to proteolytic degradation . We propose that some mature cathelicidins are naturally resistant to proteases due to their unusual primary structures . Among mammalian cathelicidins, proline-rich sequences should resist attack by serine proteases because proline prevents cleavage of the scissile bond . In hagfish cathelicidins, the unusual amino acid bromotryptophan may make the active peptides less susceptible to proteolysis for steric reasons . Such protease resistance could extend the pharmacokinetic lifetimes of cathelicidins in vivo, sustaining antimicrobial activity. Chembiochem, 2003 Nov 7, 4(11), 1151 - 63 4-fluorophenylglycine as a label for 19F NMR structure analysis of membrane-associated peptides; Afonin S et al.; The non-natural amino acid 4-fluorophenylglycine (4F-Phg) was incorporated into several representative membrane-associated peptides for dual purpose . The (19)F-substituted ring is directly attached to the peptide backbone, so it not only provides a well-defined label for highly sensitive (19)F NMR studies but, in addition, the D and L enantiomers of the stiff side chain may serve as reporter groups on the transient peptide conformation during the biological function . Besides peptide synthesis, which is accompanied by racemisation of 4F-Phg, we also describe separation of the epimers by HPLC and removal of trifluoroacetic acid . As a first example, 18 different analogues of the fusogenic peptide "B18" were prepared and tested for induction of vesicle fusion; the results confirmed that hydrophobic sites tolerated 4F-Phg labelling . Similar fusion activities within each pair of epimers suggest that the peptide is less structured in the fusogenic transition state than in the helical ground state . In a second example, five doubly labelled analogues of the antimicrobial peptide gramicidin S were compared by using bacterial growth inhibition assays . This cyclic beta-sheet peptide could accommodate both L and D substituents on its hydrophobic face . As a third example, we tested six analogues of the antimicrobial peptide PGLa . The presence of d-4F-Phg reduced the biological activity of the peptide by interfering with its amphiphilic alpha-helical fold . Finally, to illustrate the numerous uses of l-4F-Phg in (19)F NMR spectroscopy, we characterised the interaction of labelled PGLa with uncharged and negatively charged membranes . Observing the signal of the free peptide in an aqueous suspension of unilamellar vesicles, we found a linear saturation behaviour that was dominated by electrostatic attraction of the cationic PGLa . Once the peptide is bound to the membrane, however, solid-state (19)F NMR spectroscopy of macroscopically oriented samples revealed that the charge density has virtually no further influence on the structure, alignment or mobility of the peptide. FEMS Microbiol Lett, 2003 Nov 7, 228(1), 27 - 31 Isolation of a novel antimicrobial peptide gene (Sp-AMP) homologue from Pinus sylvestris (Scots pine) following infection with the root rot fungus Heterobasidion annosum; Asiegbu FO et al.; A new family of antimicrobial peptide homologues termed Sp-Amp has been discovered in Pinus sylvestris (Scots pine) . This is the first report of such proteins to be characterized in a conifer species . Sp-AMP1 was identified in a substructured cDNA library of root tissue infected with the root rot fungus Heterobasidion annosum and encodes a mature peptide of 79 amino acid residues . Three additional members of the Sp-AMP family (Sp-AMPs 2-4) encode cysteine-rich proteins of 105 amino acids, each containing an N-terminal region with a probable cleavage signal sequence . Northern analysis confirmed that Sp-AMP expression is elevated in Scots pine roots upon infection with H . annosum . These peptides share 64% amino acid identity with a mature protein from Macadamia integrifolia (MiAMP1), which allowed us to build a homology model for preliminary analysis . Southern analyses further confirmed that several copies of the gene are present in the Scots pine genome . The potential significance of Sp-AMP in the H . annosum-conifer pathosystem is discussed. Bioorg Med Chem Lett, 2003 Sep 1, 13(17), 2933 - 6 Synthesis and evaluation of methyl ether derivatives of the vancomycin, teicoplanin, and ristocetin aglycon methyl esters; McComas CC et al.; A series of methyl ether derivatives of the vancomycin, teicoplanin, and ristocetin aglycon methyl esters was synthesized and their antimicrobial activity was established . These derivatives exhibit increased activity against VanB resistant strains of bacteria equipotent with that observed with sensitive bacteria. Biosens Bioelectron, 2003 Nov 30, 19(3), 269 - 76 The influence of antimicrobial treatments on the cytocompatibility of polyurethane biosensor membranes; von Woedtke T et al.; The cytocompatibility of polyurethane membranes was tested following ultraviolet or gamma irradiation as well as treatment with hydrogen peroxide or glutaraldehyde containing solutions . Despite the fact that all of the methods had been recommended for antimicrobial treatment of glucose biosensors, the treatments investigated significantly influenced cytocompatibility characteristics . Cytotoxicity of membrane eluates was not observed following irradiation treatments . This was also the case when the membranes were repeatedly washed following chemical treatment . Cell growth upon the membranes was stimulated to a different extent after gamma and UV irradiation as well as following hydrogen peroxide treatments . Residues of an urea-based hydrogen peroxide inclusion compound caused a restriction in cell growth upon the membranes as was similarly observed with 2 and 4% glutaraldehyde solutions acting over 2 and 4 h, respectively . It is concluded that cytocompatibility in vitro reflecting the host response against a biomaterial in vivo does not only depend upon the material itself but also upon antimicrobial treatments which could have consequences for its bioperformance characteristics. Int J Immunopathol Pharmacol, 2003 Sep-Dec, 16(3), 241 - 6 Novel peptides enhance the production of nitric oxide and inducible nitric oxide synthase (iNOS) gene expression in murine macrophage; Acharya A et al.; Bioactive novel polypeptide of anuran skin has a wide range of antimicrobial properties against the infection and tumour cell . Macrophages are known to produce the Nitric oxide (NO) by a variety of cells upon activation . NO produced by the activated macrophages an important mediator for antimicrobial and tumoricidal activity . In-vitro macrophage exposed with medium alone, containing LPS, containing polypepeptides and LPS plus polypeptides for 24 h showed enhanced production of NO with respect to control and LPS treated and significant increase in NO production in LPS plus polypeptide . Western blot and PCR analysis also showed that increased production of protein expression and mRNA expression of inducible nitric oxide synthase (iNOS) . These findings suggest that novel polypeptides are potent activating agent for enhanced production of NO through activation of iNOS gene. J Burn Care Rehabil, 2003 Nov-Dec, 24(6), 395 - 9 Role of thymus oil in burn wound healing; Dursun N et al.; Thymus oil and its components are becoming increasingly popular as naturally occurring antimicrobial and antioxidant agents . The real importance of thymus on nitric oxide (NO) is unknown . NO is an important mediator in numerous physiologic and pathophysiologic events . Stasis and thrombosis in burn wound can progress as a result of the release of local mediators . The implication of NO in burn injury is not well studied . In this study, we tried to determine the role of burn-induced NO and whether thymus oil plays a protective role after a thermal injury . Rats were divided into five groups . We topically applied thymus oil, olive oil, and silverdin and sulfadiazine on the rats, respectively, during a period of 21 days after they were burned while under anesthesia . The burned control group and nonburned control group did not receive any treatment . The results of this study show that NO was overproduced by thermal injury and decreased during the days after burn injury . The decrease in rats treated with thymus and sulfadiazine was higher than the others . These data indicate that thymus oil may serve as a protective agent to the damaged tissues by decreasing the NO level . Histologic examination results show that the formation of new tissue in rats receiving thymus oil was more than other burned groups, and this finding supports our hypothesis. Arch Pharm Res, 2003 Oct, 26(10), 773 - 7 Synthesis and antimicrobial activities of some new nitroimidazole derivatives; Benkli K et al.; In this study, some new nitroimidazole derivatives were obtained from 2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethylamine dihydrochloride (4) and 1-(2-bromoethyl)-2-methyl-5-nitroimidazole (5), which were prepared using metronidazole . Compound 4 was reacted with arylisothiocyanates (6) to obtain 1-{2-(2-methyl-5-nitroimidazol-1-yl)ethyl}-3-arylthioureas (7) and the latter with alpha-bromoacetophenones (8) to give 3-{2-(2-methyl-5-nitroimidazol-1-yl)ethyl}-2-arylimino-4-aryl-4-thiazolines (9) . Also 1-{2-(2-methyl-5-nitroimidazol-1-yl)ethyl}-2-phenyl-4-arylideneimidazolin-5-ones (11) were prepared by reaction of 4 with 2-phenyl-4-arylidene-5-oxazolones (10) . The reaction of the other starting material 5 with 5-arylidenethiazolidin-2,4-dione (12) gave 3-{2-(2-methyl-5-nitroimidazol-1-yl)ethyl}-5-arylidenethiazolidin-2,4-dione (13) derivatives . Structural elucidation of the compounds was performed by IR, 1H-NMR and MASS spectroscopic data and elemental analysis results . Antimicrobial activities of the compounds were examined and moderate activity was obtained. Vet Clin North Am Food Anim Pract, 2003 Nov, 19(3), 625 - 46 Susceptibility testing for bovine respiratory and enteric disease; Apley MD; The interpretation of susceptibility results for antimicrobials with NCCLS-approved veterinary-specific breakpoints and where the methods also were NCCLS-approved are well established . When these same breakpoints are applied to other applications, however, the interpretation is not so clear . In these cases, a finding of S based on serial-dilution breakpoints puts the isolate in a defined population of bacteria with an MIC equal to or below the S breakpoint . An R result, in these cases, indicates that the organism may have an MIC equal to or greater (with no limits) than the R breakpoint . Extended-dilution testing yields more specific information about the isolate MIC . The relationship of disk-diffusion zone diameters to serial-dilution MICs is correlated on the basis of specific bacterial populations . When disk-diffusion results are interpreted for isolates other than those used for interpretive criteria development, the clinician is left wondering if the zone-diameter results now have a different relationship to serial-dilution results . Furthermore, the question of predictive value of the serial-dilution break-points still remains . The veterinary clinician should be aware of the differences in susceptibility testing predictive value for different applications . When approved veterinary-specific interpretive criteria are not available, then it is appropriate to keep records of clinical response related to susceptibility testing results for common therapies . Advice should be sought on the relationship of pathogen MICs to pharmacokinetic-pharmacodynamic parameters in these situations. Minerva Pediatr, 2003 Oct, 55(5), 415 - 38 Acute otitis media disease management; Pichichero ME et al.; A first step in management decisions regarding otitis media must focus on accurate diagnosis to distinguish normal from acute otitis media (AOM) from otitis media with effusion (OME) or a retracted tympanic membrane without middle ear effusion . There are several classification schemes for AOM that may impact management decisions: patients with acute, persistent, recurrent, or chronic AOM may have a different distribution of bacterial pathogens and a different likelihood of success from antimicrobial therapy . Patient age, prior treatment history and daycare attendance are other important variables . The natural history of AOM without antibiotic treatment is generally favorable; however, from the few studies available, this is difficult to quantitate because the diagnosis was infrequently confirmed by tympanocentesis leaving the possibility that many patients entered into these trials may not have had bacterial AOM . Antibiotic choices should reflect pharmacokinetic/pharmacodynamic data and clinical trial results demonstrating effectiveness in eradication of the most likely pathogens based on tympanocentesis sampling and antibiotic sensitivity testing . Thereafter, compliance factors such as formulation, dosing schedule and duration of treatment and accessibility factors such as availability and cost should be taken into account . The increasing prevalence of antibiotic resistance among AOM pathogens and the changing susceptibility profiles of these bacteria should be considered in antibiotic selection . Current best practice recommends amoxicillin for uncomplicated AOM; continuing or switching to an alternative antibiotic based on clinical response after 48 hours of therapy; and selection of second line antibiotics as first line choices when the patient has already been on an antibiotic within the previous month or is otitis prone . Preferred second-line agents frequently noted in various guidelines include amoxicillin/clavulanate, cefdinir, cefpodoxime, cefprozil, and cefuroxime . Three injections of ceftriaxone or gatifloxacin (when approved) or diagnostic/therapeutic tympanocentisis (when approved) become a third-line treatment option . No single antibiotic or management strategy is ideal for all patients. J Immunol, 2003 Nov 15, 171(10), 5233 - 43 Timing of IFN-beta exposure during human dendritic cell maturation and naive Th cell stimulation has contrasting effects on Th1 subset generation: a role for IFN-beta-mediated regulation of IL-12 family cytokines and IL-18 in naive Th cell differentiation; Nagai T et al.; Type I IFNs, IFN-alpha and IFN-beta, are early effectors of innate immune responses against microbes that can also regulate subsequent adaptive immunity by promoting antimicrobial Th1-type responses . In contrast, the ability of IFN-beta to inhibit autoimmune Th1 responses is thought to account for some of the beneficial effects of IFN-beta therapy in the treatment of relapsing remitting multiple sclerosis . To understand the basis of the paradoxical effects of IFN-beta on the expression of Th1-type immune responses, we developed an in vitro model of monocyte-derived dendritic cell (DC)-dependent, human naive Th cell differentiation, in which one can observe both positive and negative effects of IFN-beta on the generation of Th1 cells . In this model we found that the timing of IFN-beta exposure determines whether IFN-beta will have a positive or a negative effect on naive Th cell differentiation into Th1 cells . Specifically, the presence of IFN-beta during TNF-alpha-induced DC maturation strongly augments the capacity of DC to promote the generation of IFN-gamma-secreting Th1 cells . In contrast, exposure to IFN-beta during mature DC-mediated primary stimulation of naive Th cells has the opposite effect, in that it inhibits Th1 cell polarization and promotes the generation of an IL-10-secreting T cell subset . Studies with blocking mAbs and recombinant cytokines indicate that the mechanism by which IFN-beta mediates these contrasting effects on Th1 cell generation is at least in part by differentially regulating DC expression of IL-12 family cytokines (IL-12 and/or IL-23, and IL-27) and IL-18. Biomacromolecules, 2003 Nov-Dec, 4(6), 1811 - 7 Structure-activity relationships of oligoguanidines-influence of counterion, diamine, and average molecular weight on biocidal activities; Albert M et al.; A series of different oligomeric guanidines was prepared by polycondensation of guanidinium salts and four different diamines under varying conditions . The antimicrobial activities were evaluated against two to four microorganisms . MALDI-TOF-MS was used to analyze the different oligomers . It was found that in each case three major product type series are dominating . These series are linear and terminated with one guanidine and one amino group (type A), two amino groups (type B), or two guanidine groups (type C), respectively . By using 1,2-bis(2-aminoethoxy)ethane as the amino component, a considerable amount of two additional product series, consisting of cyclic structures, was detected (type D and E) . It turned out that an average molecular mass of about 800 Da is necessary for an efficient antimicrobial activity . Lower Mw's result in a rapid decrease of activity . By using guanidinium carbonate as the starting material, oligomers with low biocidal activity were obtained, which was caused by incorporation of urea groups during the polycondensation . The diamine determines the distance between two guanidinium groups . It was shown that both 1,2-bis(2-aminoethoxy)ethane and hexamethylenediamine give oligomers with high biocidal activity . By increasing the chain length of the diamine, the biocidal activity drops again. Biomacromolecules, 2003 Nov-Dec, 4(6), 1457 - 65 Chitosan as antimicrobial agent: applications and mode of action; Rabea EI et al.; Chitosan, a hydrophilic biopolymer industrially obtained by N-deacetylation of chitin, can be applied as an antimicrobial agent . The current review of 129 references describes the biological activity of several chitosan derivatives and the modes of action that have been postulated in the literature . It highlights the applications of chitosan as an antimicrobial agent against fungi, bacteria, and viruses and as an elicitor of plant defense mechanisms. Drug Dev Ind Pharm, 2003 Oct, 29(9), 1027 - 33 Degradation kinetics of somatostatin in aqueous solution; Herrmann J et al.; The degradation kinetics of somatostatin (somatotropin release inhibiting factor), a cyclic tetradecapeptide, was investigated as a function of temperature, pH, ionic strength, buffer type, and buffer concentration . In addition, the effect of different container materials in which the solutions were stored and the presence of an antimicrobial agent for in vitro use was examined . The degradation of somatostatin followed first-order kinetics under all investigated conditions . The pH-stability profile showed a well-defined stability optimum around pH 3.7 . The degradation was accelerated at higher buffer concentrations, phosphate buffer being significantly more detrimental than acetate buffer . The ionic strength and the drug concentration had virtually no effect on the degradation rate . When general purpose glass vials were used as storage containers, degradation was faster due to release of alkali from the container material . The solution properties, i.e., pH, buffer type, buffer capacity, and the experimental setup such as container material and sterile conditions need to be carefully selected or maintained, in order to avoid accelerated degradation. J Clin Microbiol, 2003 Nov, 41(11), 5121 - 6 Detection and differentiation of Mycobacterium tuberculosis and nontuberculous mycobacterial isolates by real-time PCR; Shrestha NK et al.; Mycobacteria cause a variety of illnesses that differ in severity and public health implications . The differentiation of Mycobacterium tuberculosis from nontuberculous mycobacteria (NTM) is of primary importance for infection control and choice of antimicrobial therapy . Despite advances in molecular diagnostics, the ability to rapidly diagnose M . tuberculosis infections by PCR is still inadequate, largely because of the possibility of false-negative reactions . We designed and validated a real-time PCR for mycobacteria by using the LightCycler system with 18 reference strains and 168 clinical mycobacterial isolates . All clinically significant mycobacteria were detected; the mean melting temperatures (with 99.9% confidence intervals {99.9% CI} in parentheses) for the different mycobacteria were as follows: M . tuberculosis, 64.35 degrees C (63.27 to 65.42 degrees C); M . kansasii, 59.20 degrees C (58.07 to 60.33 degrees C); M . avium, 57.82 degrees C (57.05 to 58.60 degrees C); M . intracellulare, 54.46 degrees C (53.69 to 55.23 degrees C); M . marinum, 58.91 degrees C (58.28 to 59.55 degrees C); rapidly growing mycobacteria, 53.09 degrees C (50.97 to 55.20 degrees C) or 43.19 degrees C (42.19 to 44.49 degrees C) . This real-time PCR assay with melting curve analysis consistently accurately detected and differentiated M . tuberculosis from NTM . Detection of an NTM helps ensure that the negative result for M . tuberculosis is a true negative . The specific melting temperature also provides a suggestion of the identity of the NTM present, when the most commonly encountered mycobacterial species are considered . In a parallel comparison, both the LightCycler assay and the COBAS Amplicor M . tuberculosis assay correctly categorized 48 of 50 specimens that were proven by culture to contain M . tuberculosis, and the LightCycler assay correctly characterized 3 of 3 specimens that contained NTM. Bioorg Med Chem, 2003 Nov 17, 11(23), 5035 - 43 Analysis of structural features of bis-quaternary ammonium antimicrobial agents 4,4'-(alpha,omega-polymethylenedithio)bis (1-alkylpyridinium iodide)s using computational simulation; Ohkura K et al.; The bis-quaternary ammonium compounds (QACs) consisted of two identical alkylpyridinium rings and a bridge structure linking the rings to each other . The QACs have a methylene bridge except for 4DCABP-P,12 which has a phenyl ring as a bridge . These bis-QACs are as follows; amide type: N,N'-tetramethylenebis(1-dodecyl-4-carbamoylpyridinium iodide) (4BCAP-4,12), N,N'-hexamethylenebis(1-decyl-4-carbamoylpyridinium iodide) (4BCAP-6,10), anti-amide type: 4,4'-(1,4-tetramethylenedicarbonyldiamine)bis(1-decylpyridinium iodide) (4DCABP-4,10), 4,4'-(1,4-tetramethylenedicarbonyldiamine)bis (1-dodecylpyridinium iodide) (4DCABP-4,12), 4,4'-(1,4-phenyldicarbonyldiamine)bis(1-dodecylpyridinium iodide) (4DCABP-P,12), ester type: 4,4'-(1,6-hexamethylenedioxydicarbonyl)bis(1-dodecylpyridinium iodide) (4DOCBP-6,12), thioether type: 4,4'-(1,6-hexamethylenedithio)bis(1-octylpyridinium iodide) (4DTBP-6,8) . From the investigation of the relationship between the median lethal dose (LD(50)) and the minimum inhibitory concentration (MIC) of these compounds, 4DTBP-6,8 as a disinfectant, seems to be very safe for human cells . The global minimum of 4DTBP-6,8 were searched and 1125 conformers obtained . The solvation free energy (dGW) of nine samples, which were extracted from these 1125 conformers, was calculated and two minimum points of dGW were observed . In the conformer-energy analysis of four types of model bridge-molecule, the thioether type bridge indicated a gradual energy increment, while the other three (amide, anti-amide, ester) types indicated an energy jump point in their profiles . Then we considered that the delicate balance between hydrophobicity and structural feature in the bridge-region of 4DTBP-6,8 molecule seemed to be related to its safety antibacterial activity. Perit Dial Int, 2003 Sep-Oct, 23(5), 450 - 5 Increased severity of Escherichia coli peritonitis in peritoneal dialysis patients independent of changes in in vitro antimicrobial susceptibility testing; Valdes-Sotomayor J et al.; OBJECTIVE: Despite improvements in peritoneal dialysis (PD) technique, peritonitis continues to be one of the most frequent complications of PD . Nonresolving peritonitis remains a risk for severe anatomical peritoneal changes that may limit the viability of the membrane for dialysis purposes . We have observed remarkably poor outcome of peritonitis caused by Escherichia coli in the past 6 years . With its very low response rate to broad-spectrum antibiotics, the increased severity of E . coli peritonitis deteriorates peritoneal function and affects patient outcome . DESIGN: Retrospective study . SETTING: Two large PD units in two university hospitals . PATIENTS AND METHODS: The total number of patients reviewed was 456 . The records of 49 E . coli peritonitis episodes were studied.The observation period started in 1980 and ended in March 2001 . Sixteen males and 19 females were included . Severity was defined in terms of days of peritoneal inflammation, lack of response to a potentially useful antibiotic, requirement for catheter removal, and/or laparotomy . Study cases (study group) were those episodes appearing after 1996 (when the first severe cases appeared) and historic controls were episodes occurring before 1996 . RESULTS: In the study group, 18 peritonitis episodes developed in 15 patients . In the control group, 31 peritonitis episodes developed in 20 patients . There were no significant differences in clinical presentation; however, the outcome was significantly poorer for the later period . A severe outcome occurred in 50% of study versus 10% of control patients . In fact, 68% of the episodes registered before 1996 were cured in 3 days or less . Concurring with this trend, the numbers of surgical interventions and catheter removals were also higher in the study group . Strikingly, E . coli did not show changes in in vitro susceptibility testing to antibiotics, although the in vivo response was much worse . CONCLUSIONS: We describe a change in the virulence of E . coli peritonitis episodes over the past 5 years leading to a high percentage of treatment failure, which does not depend on antibiotic sensitivity and seems to be dependent on changes in host response mechanisms. J Clin Pediatr Dent, 2003 Fall, 28(1), 47 - 52 Biological factors in dental caries: role of saliva and dental plaque in the dynamic process of demineralization and remineralization (part 1); Hicks J et al.; Dental caries is a complex disease process that afflicts a large proportion of the world's population, regardless of gender, age and ethnicity, although it does tend to affect more indivduals with a low socioeconomic status to a greater extent . The process of dental caries is dependent upon biological factors that are present within the saliva and dental plaque . There are many different agents within saliva and plaque that serve to protect the tooth surface against caries development . Salivary flow rate, buffering capacity, antimicrobial activity, microorganism aggregation and clearance from the oral cavity, immune surveillance, and calcium phosphate binding proteins all interact to inhibit or reverse demineralization of exposed tooth surfaces . Cariogenic bacteria levels within the saliva and plaque determine whether caries will occur or not, and the concentration in saliva and plaque are intimately related to the type of carbohydrate ingestion and the frequency of ingestion, as well as the oral hygiene practiced by the individual. Nature, 2003 Nov 6, 426(6962), 33 - 8 The immune response of Drosophila; Hoffmann JA; Drosophila mounts a potent host defence when challenged by various microorganisms . Analysis of this defence by molecular genetics has now provided a global picture of the mechanisms by which this insect senses infection, discriminates between various classes of microorganisms and induces the production of effector molecules, among which antimicrobial peptides are prominent . An unexpected result of these studies was the discovery that most of the genes involved in the Drosophila host defence are homologous or very similar to genes implicated in mammalian innate immune defences . Recent progress in research on Drosophila immune defence provides evidence for similarities and differences between Drosophila immune responses and mammalian innate immunity. Appl Environ Microbiol, 2003 Nov, 69(11), 6777 - 84 Binding of pediocin PA-1 with anionic lipid induces model membrane destabilization; Gaussier H et al.; To obtain molecular insights into the action mode of antimicrobial activity of pediocin PA-1, the interactions between this bacteriocin and dimyristoylphosphatidylcholine (DMPC) or dimyristoylphosphatidylglycerol (DMPG) model membranes have been investigated in D(2)O at pD 6 by Fourier transform infrared spectroscopy . The interactions were monitored with respect to alteration of the secondary structure of pediocin, as registered by the amide I' band, and phospholipid conformation, as revealed by the methylene nu(s)(CH(2)) and carbonyl nu(C;O) stretching vibrations . The results show that no interaction between pediocin and DMPC occurs . By contrast, pediocin undergoes a structural reorganization in the presence of DMPG . Upon heating, pediocin self-aggregates, which is not observed for this pD in aqueous solution . The gel-to-crystalline phase transition of DMPG shifts to higher temperatures with a concomitant dehydration of the interfacial region . Our results indicate that pediocin is an extrinsic peptide and that its action mechanism may lie in a destabilization of the cell membrane. Int J Antimicrob Agents, 2003 Nov, 22(5), 479 - 86 Quinoline and cyanine dyes--putative anti-MRSA drugs; Wainwright M et al.; One way in which drug-resistant bacteria may be attacked is to screen new series of candidate compounds . Quaternary quinoline compounds and dyes were studied by Carl Browning (1887-1972) and Julius Cohen (1859-1935) . A remarkable part of Browning and Cohen's work was the early development of structure-activity relationships for their series of compounds . Thus cationic species were found generally to be more effective antibacterials than neutrals or anionics, and the testing of partial or deconstructed active molecules was also carried out . Much of this work underpinned the fuller understanding of e.g . aminoacridine action developed by Adrien Albert (1907-1989), himself also a collaborator of Browning . Analysis of the activity of a range of compounds developed by Browning and Cohen suggests that these might again be examined as topical antimicrobials in the fight against methicillin-resistant S . aureus (MRSA) and other resistant bacteria. Int J Antimicrob Agents, 2003 Nov, 22(5), 465 - 78 Antimicrobial peptides in animals and their role in host defences; Brogden KA et al.; Domesticated animals have a large variety of antimicrobial peptides that serve as natural innate barriers limiting microbial infection or, in some instances, act as an integral component in response to inflammation or microbial infection . These peptides differ in size, composition, mechanisms of activity and range of antimicrobial specificities . They are expressed in many tissues, polymorphonuclear leukocytes, macrophages and mucosal epithelial cells . There is a small group of anionic antimicrobial peptides found in ruminants and a much larger group of cationic antimicrobial peptides found in all domesticated animals . The cationic peptides include linear, helical peptides, linear peptides rich in proline and cysteine-stabilized peptides with a beta-sheet and are commonly referred to as cathelicidins and defensins . These peptides are generally broad-spectrum for Gram-positive bacteria, Gram-negative bacteria and fungi (e.g . myeloid antimicrobial peptides, alpha-, beta-defensins, and protegrins) or are specific to one of these groups (e.g . porcine cecropin P1, Bac5, Bac7, PR-39 and prophenin). Comp Biochem Physiol B Biochem Mol Biol, 2003 Nov, 136(3), 505 - 13 Antibacterial properties of serum from the American alligator (Alligator mississippiensis); Merchant ME et al.; Treatment of alligator (Alligator mississippiensis) and human serum samples with Escherichia coli resulted in a time- and concentration-dependent inhibition of bacterial proliferation . When inoculated with E . coli, alligator serum exhibited 10-fold lower bacterial survival rates after 1 h than human serum . In addition, the antibacterial spectrum of alligator serum was shown to be much broader than that of human serum, with growth inhibition occurring in 100% of bacterial strains tested (compared to only 35% for human serum) . Additional results showed that the antimicrobial activities of alligator serum could be completely inhibited by preincubation with proteases, indicating the proteinaceous nature of the antimicrobial activities . Furthermore, incubation of alligator serum at 56 degrees C for 30 min (classical human serum complement inactivation conditions) obliterated all antimicrobial properties of the alligator serum . The antibacterial activities occurred relatively quickly in vitro, with significant activity occurring within 5 min of inoculation with E . coli and maximal activity at 20 min . Also, the antimicrobial activity exhibited temperature dependence, with a substantial decrease in activity below 15 degrees C . These data suggest that the antimicrobial properties of alligator serum may be due to an active serum complement system. Mayo Clin Proc, 2003 Nov, 78(11), 1409 - 11 Ocular ethambutol toxicity; Melamud A et al.; Ethambutol is an antimicrobial agent used frequently to treat tuberculosis . The most commonly recognized toxic effect of ethambutol is optic neuropathy, which generally is considered uncommon and reversible in medical literature . We describe a 43-year-old man who developed signs and symptoms of bilateral optic neuropathy during treatment with ethambutol . This case and a review of the literature show the severe and unpredictable nature of ethambutol toxicity and its potential for irreversible vision loss despite careful ophthalmologic monitoring. Transgenic Res, 2003 Oct, 12(5), 597 - 605 Expression of lysostaphin in milk of transgenic mice affects the growth of neonates; Mitra A et al.; As an initial step towards enhancing mastitis resistance in dairy animals, we generated BLG-Lys transgenic mice that secrete lysostaphin, a potent antistaphylococcal protein, in their milk . In the current study, we continue our assessment of lysostaphin as a suitable antimicrobial protein for mastitis resistance and have investigated mammary gland development and function in three lines of transgenic mice . As the lines were propagated, there was a tendency for fewer BLG-Lys litters to survive to weaning (51% as compared to 90% for nontransgenic lines, p = 0.080) . Nontransgenic pups fostered on dams from these three lines exhibited diminished growth rates during the first week of lactation . Rates of gain became comparable to pups on nontransgenic dams at later time points . Initial slow growth also resulted in decreased weaning weights for pups nursed by transgenic dams (15.35 +/- 0.27 g) when compared to pups delivered and nursed by nontransgenic dams (18.61 +/- 0.61 g; p < 0.001), but the effect was temporary, as similar weights were attained by adulthood . Milk yield at peak lactation was not different between BLG-Lys (0.79 +/- 0.33 g) and nontransgenic (0.91 +/- 0.38 g; p = 0.166) dams . Histological examination of the transgenic mammary glands during gestation revealed no differences when compared to control glands; however, at early lactational stages, the BLG-Lys glands exhibited less alveolar area than control glands and a delay in lobulo-alveolar maturation . The results clearly demonstrate reduced growth of neonates on BLG-Lys dams; whether the poor pup performance can be attributed to delayed mammary development or the gland development merely reflects reduced suckling stimuli from the pups remains to be determined. Microsc Res Tech, 2003 Dec 1, 62(5), 423 - 30 Transmission electron microscopic observations of membrane effects of antibiotic cecropin B on Escherichia coli; Chen HM et al.; The pathway of cell membrane lysis by the peptide antibiotic cecropin B (CB), which contains both a hydrophobic and an amphipathic alpha-helix, was analysed by assessing the morphological changes of Escherichia coli following treatment with the peptide . Exposure of green fluorescent protein (GFP)-expressing E . coli to CB does not lead to an efflux of GFP . Moreover, transmission electron microscopic (TEM) examination of cecropin B-treated cells showed that severe swelling precedes cell death and that the outer membrane becomes distended away from the plasma membrane . Using immuno-gold staining and TEM of E . coli expressing the maltose-binding protein in the cytoplasm, it was apparent that the protein remains restricted to the cytoplasmic compartment . These observations suggest that CB causes gross disruption of the outer membrane of Gram-negative bacteria . Circular dichroism measurements of CB in the presence of cell membrane-mimicking liposomes showed that CB forms secondary structure dependent on the ratio of {lipid}/{peptide} . These observations from this study are important for the future design of custom antimicrobial peptides . Intensive Care Med, 2003 Dec, 29(12), 2327 - 9 Epub 2003 Nov 05. Disseminated tuberculosis, pulmonary aspergillosis and cutaneous herpes simplex infection in a patient with infliximab and methotrexate; van der Klooster JM et al.; CASE PRESENTATION: Despite chemoprophylaxis with isoniazid a 58-year-old Creole patient with mild rheumatoid arthritis developed disseminated tuberculosis, pulmonary aspergillosis and cutaneous herpes simplex infection during treatment with infliximab and methotrexate . TREATMENT: The patient received antituberculous drugs (ethambutol, isoniazid, pyrazinamide, rifampicin), amphotericin B, flucytosine, and valaciclovir, along with prolonged intensive care treatment and mechanical ventilation . CONCLUSIONS: The present case confirms that isoniazid prophylaxis (300 mg once daily, during 6 months) does not protect against the reactivation and dissemination of latent tuberculosis . It also shows that combined treatment with infliximab and methotrexate may induce severe immunosuppression with prolonged leukocytopenia and depressed cellular immunity, leading to multiple opportunistic infections . Extensive diagnostic testing, early start of antimicrobial therapy and enteral immunonutrition, and further infection prevention with selective decontamination of the digestive tract may have been the key to a good clinical outcome. Microbiology, 2003 Nov, 149(Pt 11), 3139 - 53 The 64 508 bp IncP-1beta antibiotic multiresistance plasmid pB10 isolated from a waste-water treatment plant provides evidence for recombination between members of different branches of the IncP-1beta group; Schluter A et al.; The complete 64508 bp nucleotide sequence of the IncP-1beta antibiotic-resistance plasmid pB10, which was isolated from a waste-water treatment plant in Germany and mediates resistance against the antimicrobial agents amoxicillin, streptomycin, sulfonamides and tetracycline and against mercury ions, was determined and analysed . A typical class 1 integron with completely conserved 5' and 3' segments is inserted between the tra and trb regions . The two mobile gene cassettes of this integron encode a beta-lactamase of the oxacillin-hydrolysing type (Oxa-2) and a gene product of unknown function (OrfE-like), respectively . The pB10-specific gene load present between the replication module (trfA1) and the origin of vegetative replication (oriV) is composed of four class II (Tn3 family) transposable elements: (i) . a Tn501-like mercury-resistance (mer) transposon downstream of the trfA1 gene, (ii) . a truncated derivative of the widespread streptomycin-resistance transposon Tn5393c, (iii) . the insertion sequence element IS1071 and (iv) . a Tn1721-like transposon that contains the tetracycline-resistance genes tetA and tetR . A very similar Tn501-like mer transposon is present in the same target site of the IncP-1beta degradative plasmid pJP4 and the IncP-1beta resistance plasmid R906, suggesting that pB10, R906 and pJP4 are derivatives of a common ancestor . Interestingly, large parts of the predicted pB10 restriction map, except for the tetracycline-resistance determinant, are identical to that of R906 . It thus appears that plasmid pB10 acquired as many as five resistance genes via three transposons and one integron, which it may rapidly spread among bacterial populations given its high promiscuity . Comparison of the pB10 backbone DNA sequences with those of other sequenced IncP-1beta plasmids reveals a mosaic structure . While the conjugative transfer modules (trb and tra regions) and the replication module are very closely related to the corresponding segments of the IncP-1beta resistance plasmid R751 and even more similar to the IncP-1beta degradative plasmids pTSA and pADP-1, the stable inheritance operons klcAB-korC and kleAEF are most similar to those of the IncP-1beta resistance plasmid pB4, and clearly less similar to the other IncP-1beta plasmids . This suggests that IncP-1beta plasmids can undergo recombination in the environment, which may enhance plasmid diversity and bacterial adaptability. Am J Public Health, 2003 Nov, 93(11), 1910 - 4 Trends in antimicrobial prescribing for bronchitis and upper respiratory infections among adults and children; Mainous AG 3rd et al.; OBJECTIVES: This study examined antimicrobial prescribing patterns for adults and children with bronchitis or upper respiratory infections (URIs) before and after release of nationally disseminated pediatric practice recommendations . METHODS: Data from the 1993, 1995, 1997, and 1999 National Ambulatory Medical Care Survey were used to evaluate prescriptions for antimicrobials for URIs and bronchitis . RESULTS: From 1993 to 1999, the proportion of children receiving antimicrobials after visits for URIs and bronchitis decreased . However, the use of broad-spectrum antimicrobials rose from 10.6% of bronchitis visits to 40.5% . Prescriptions of antimicrobials for adults with URIs or bronchitis showed a decrease between 1993 and 1999 . CONCLUSIONS: Although antimicrobial prescribing for URIs and bronchitis has decreased for both children and adults, the prescribing of broad-spectrum antibiotics among children has shown a proportional rise. Regul Pept, 2003 Nov 15, 116(1-3), 139 - 46 Identification of three novel Phyllomedusa sauvagei dermaseptins (sVI-sVIII) by cloning from a skin secretion-derived cDNA library; Chen T et al.; The defensive skin secretions of many amphibians contain a wide spectrum of biologically active compounds, particularly antimicrobial peptides that act as a first line of defence against bacterial infection . Here we describe for the first time the identification of three novel dermaseptin-related peptides (dermaseptins sVI-sVIII) whose primary structures were deduced from cDNAs cloned from a library constructed from lyophilised skin secretion of the South American hylid frog, Phyllomedusa sauvagei . The molecular masses of each were subsequently confirmed by interrogation of archived LC/MS files of fractionated skin secretion followed by automated Edman degradation sequencing . The heterogeneity of primary structures encountered in amphibian skin antimicrobial peptides may in part be explained by individual variation-a factor essential for selective functional molecular evolution and perhaps, ultimately in speciation. Am J Med, 2003 Nov, 115(7), 529 - 35 Inappropriate initial antimicrobial therapy and its effect on survival in a clinical trial of immunomodulating therapy for severe sepsis; Harbarth S et al.; PURPOSE: To examine the effect of inappropriate initial antimicrobial therapy on the prognosis of patients with sepsis who were enrolled in a clinical trial of an immunomodulating agent conducted in 108 hospitals in North America and Europe . METHODS: We assessed initial antimicrobial choice and results of microbiologic cultures in 904 patients who had microbiologically confirmed severe sepsis or early septic shock . If a patient did not receive at least one antimicrobial agent to which the causative microorganisms were susceptible within 24 hours from the diagnosis of severe sepsis, then the initial antimicrobial treatment was considered to be inappropriate . A propensity score that adjusted for factors associated with inappropriate antimicrobial treatment was calculated and included in multivariable models to adjust for confounding . RESULTS: A total of 468 patients (52%) had documented bloodstream infection, and 211 patients (23%) received inappropriate initial antimicrobial therapy . Characteristics associated with inappropriate treatment were study enrollment in Europe, admission to surgery, nosocomial infection, infection with multiresistant microorganisms, and fungal or polymicrobial infection (all P <0.05) . The 28-day mortality was 24% (168/693) for patients in the adequately treated group versus 39% (82/211) for patients receiving inappropriate initial antimicrobial therapy (P <0.001) . After adjusting for comorbid conditions, severity of illness, site of infection, and the propensity score, inappropriate antimicrobial therapy was independently associated with increased mortality (odds ratio = 1.8; 95% confidence interval: 1.2 to 2.6) . CONCLUSION: In a large cohort of patients with microbiologically confirmed severe sepsis, appropriate initial antimicrobial therapy was an important determinant of survival . New approaches aimed at improving detection and treatment of early sepsis are needed. Int J Tuberc Lung Dis, 2003 Nov, 7(11), 1027 - 32 The potential of human neutrophil peptides in tuberculosis therapy; Fu LM; The problems of drug resistance and bacterial persistence in tuberculosis have prompted scientists to search for clues from the latest advances in microbiology and immunology . Recent research on human neutrophil peptides (HNPs) has highlighted their bactericidal action against Mycobacterium tuberculosis and suggested that neutrophils may play a more important defensive role in tuberculosis than previously thought . Human neutrophil peptides belong to a family of antimicrobial and cytotoxic peptides known as 'defensins' . Neutrophils use both oxidative and non-oxidative microbicidal mechanisms to provide the host with innate immunity against microbial infections . Defensins are most abundant among an array of oxygen-independent antimicrobial proteins and peptides in neutrophil granules . Defensins are effective against a wide spectrum of microbes including bacteria, viruses, fungi, spirochetes and mycobacteria . In addition to direct antimicrobial activity, HNPs can potentially influence the inflammatory or immune responses by modulating cytokine production or acting like opsonins or chemotactic factors . HNPs are active against M . tuberculosis grown in vitro or within macrophages . HNPs released by neutrophils recruited in the early lesion could attract monocytes to the site and macrophages may in vivo uptake the extracellular HNPs and kill the intracellular pathogens . As such, HNPs are potential therapeutic agents against tuberculosis . HNPs are also cytotoxic against a wide range of normal mammalian cells; however, there is evidence that defensins may not cause significant cytotoxicity at the therapeutic level . Finally, the clinical application of HNPs must be evaluated in the context of possible drug resistance, as some resistance-associated genes have been identified. J Chemother, 2003 Oct, 15(5), 466 - 71 Comparison of five antimicrobial regimens for the treatment of brucellar spondylitis: a prospective, randomized study; Bayindir Y et al.; Brucellosis, a zoonosis with worldwide distribution, is a systemic infection and still an important public health problem in Turkey . The best antimicrobial combination and schedule for the treatment of brucellosis with spondylitis has not yet been clearly determined . In a prospective and randomized study, we compared the efficacy of five antimicrobial regimens for treatment of 102 patients with lumbar brucellar spondylitis . Patients were randomly assigned to receive antimicrobial combination therapy . Twenty patients received streptomycin 1 g/day intramuscularly for 15 days and tetracycline-HCl, 500 mg every 6 h orally for 45 days (ST), 21 patients received streptomycin 1 g/day i.m . for 15 days and doxycycline 100 mg every 12 h orally for 45 days (SD), 20 patients received doxycycline 100 mg every 12 h orally for 45 days and rifampicin 15 mg/kg per day in a single morning dose orally for 45 days (DR), 19 patients received ofloxacin, 200 mg every 12 h orally for 45 days and rifampicin 15 mg/kg per day in a single morning dose orally for 45 days (OR), and 22 patients received streptomycin 1 g/day i.m . for 15 days and doxycycline 100 mg every 12 h orally for 45 days plus rifampicin 15 mg/kg per day in a single morning dose orally for 45 days (SDR) . Initial therapeutic failure occurred in 2 patients (10%) in the ST regimen group, 4 patients (19%) in the SD group, 3 patients (15%) in the DR group and 5 patients (26%) in the OR regimen . In addition, 2 patients (10%) in the DR group and 5 patients (26%) in the OR regimen relapsed during the follow-up period . There was no relapse in any patients in the ST, SD, and SDR groups . The response rates were 90% in the ST and 81% in the SD groups . In contrast, there was a maximum good response (100%) and no relapse in the SDR group . In conclusion, a combination of doxycycline, streptomycin, and rifampicin can be recommended as therapy for brucellar spondylitis and to reduce relapse rates. J Clin Invest, 2003 Nov, 112(9), 1300 - 7 Pharmacological inhibition of quorum sensing for the treatment of chronic bacterial infections; Hentzer M et al.; Traditional treatment of infectious diseases is based on compounds that aim to kill or inhibit bacterial growth . A major concern with this approach is the frequently observed development of resistance to antimicrobial compounds . The discovery of bacterial-communication systems (quorum-sensing systems), which orchestrate important temporal events during the infection process, has afforded a novel opportunity to ameliorate bacterial infection by means other than growth inhibition . Compounds able to override bacterial signaling are present in nature . Herein we discuss the known signaling mechanisms and potential antipathogenic drugs that specifically target quorum-sensing systems in a manner unlikely to pose a selective pressure for the development of resistant mutants. Gene, 2003 Nov 13, 319, 43 - 53 Characterization and transcriptional profiles of three Spodoptera frugiperda genes encoding cysteine-rich peptides . A new class of defensin-like genes from lepidopteran insects? Volkoff AN, Rocher J, d'Alencon E, Bouton M, Landais I, Quesada-Moraga E, Vey A, Fournier P, Mita K, Devauchelle G. The present work describes sequence and transcription of three Spodoptera frugiperda genes encoding 6-cysteine-rich peptides . Sequence alignments indicate that the predicted peptides belong to the insect defensin family, although phylogenetic analyses suggest they form a cluster distinct from that of other neopteran insect defensins . The three genes were identified in a non-immune-challenged Sf9 cells cDNA (DNA complementary to RNA) library (Landais et al., Bioinformatics, in press) and were named spodoptericin, Sf-gallerimycin and Sf-cobatoxin . Spodoptericin is a novel defensin-like gene that appears to be weakly up-regulated following injection of bacteria and fungi . Interestingly, no sequence motif clearly homologous to cis regulatory element involved in the regulation of antimicrobial genes was found . An homologue of the spodoptericin gene was identified in the SilkBase Bombyx mori cDNA library . Sf-gallerimycin is related to the Galleria mellonella gallerimycin gene and is induced after immune challenge by injection of bacteria in the larval fat body as well as in hemocytes . In silico analysis of the sequence upstream from the cDNA reveals the presence of at least one motif homologous to a nuclear factor kappaB (NF-kappaB) binding site . Finally, Sf-cobatoxin is related to the G . mellonella cobatoxin-like gene . Despite high levels of constitutive expression compared to the two previous genes, transcription of Sf-cobatoxin is increased after immune, in particular, bacterial challenge . We therefore confirm that these three genes encode potential candidate molecules involved in S . frugiperda innate humoral response. FEBS Lett, 2003 Nov 6, 554(1-2), 100 - 4 Individual substitution analogs of Mel(12-26), melittin's C-terminal 15-residue peptide: their antimicrobial and hemolytic actions; Yan H et al.; Residues 1-9 of M(12-26) (GLPALISWIKRKRQQ-NH2), the C-terminal 15-residue segment of melittin, were substituted individually to change the hydropathicities in these positions . Antimicrobial and hemolytic activities of these peptides were determined . The results showed increased antimicrobial activities with increased hydrophobicities at almost all the positions studied . The effects at positions 2, 5, 8 and 9 were significant while the effects at the other positions were small . These two groups of residues were located on the opposite faces of the alpha-helix . In other words, the hydrophobicities of the two faces were favorable, but one face (the more favorable face) contributed more to the antimicrobial activities than the other (the less favorable face) . The hydrophobicity, not the amphipathicity, seems to be crucial for antimicrobial activity . In contrast, the hydrophobicity of one face was favorable but the other was unfavorable for the hemolytic activity, indicating that the amphipathicity may be important for hemolysis . Interestingly, the more favorable face for antimicrobial activity was located opposite to the favorable face for hemolytic activity, indicating the direction of the hydrophobic face for the antimicrobial activity and direction of the amphipathicity for the hemolytic activity were also important. Biochemistry, 2003 Nov 11, 42(44), 12866 - 74 Analysis of membrane-binding properties of dermaseptin analogues: relationships between binding and cytotoxicity; Gaidukov L et al.; To understand relationships between membrane-binding properties of cytolytic peptides and resulting cytotoxicity, we investigated interactions of dermaseptin analogues with model bilayers by means of surface plasmon resonance . First, we tested the system by comparing two native dermaseptins, S1 and S4, whose binding properties were previously characterized in different experimental systems . Validation experiments revealed deviations from the one-to-one interaction model and indicated the binding to proceed by a two-stage mechanism . By calculation of apparent affinity constants and individual affinities for both steps of the interaction, the biosensor technology was able to distinguish between surface-bound peptides that subsequently penetrated into the bilayer and peptides that remained essentially superficially bound . This data interpretation was sustained after analysis of a series of dermaseptin S4 derivatives whose binding data were compared with cytotoxicity, revealing cytolytic activity to correlate mainly with insertion affinity . The data indicate that the potency of highly cytolytic peptides such as K(4)K(20)-S4 is not due to the highest membrane adhesion affinity but to the highest propensity for the inserted state . Similarly, truncated derivatives of 16, 13, and 10 residues showed a progressive reduction in cytotoxicity that best correlated with progressive reduction in insertion affinity . Support for the adhesion versus inserted states was provided by proteolytic experiments with RBC-bound peptides that demonstrated K(4)K(20)-S4 to be protected from enzymatic cleavage, unlike its 13-mer derivative . Overall, using the two-stage model proved instrumental in investigating membrane-binding properties of antimicrobial peptides and capable of explaining the cytolytic properties of closely related analogues. Phytother Res, 2003 Nov, 17(9), 1082 - 7 Biological activities of Prunella vulgaris extract; Psotova J et al.; The organic fraction (OF; 25.7% w/w of rosmarinic acid) of Prunella vulgaris (total extract) was found to exhibit the following: scavenging activity on diphenylpicrylhydrazyl radical (DPPH), inhibition of in vitro human LDL Cu(II)-mediated oxidation, protection of rat mitochondria and rat hepatocytes exposed to either tert-butyl hydroperoxide, or to Cu(II) and Fe(III) ions . OF also showed a potential to inhibit rat erythrocyte haemolysis and it reduced the production of LTB(4) in bovine PMNL generated by the 5-lipoxygenase pathway . Other observations included antiproliferative effects against HaCaT cells and mouse epidermal fibroblasts and a moderate OF antimicrobial activity on gram-positive bacteria . Rosmarinic, caffeic and 3-(3,4-dihydroxyphenyl)lactic acids exhibited less potent activity than the plant extract in all bioassays . The antioxidative, antimicrobial, together with antiviral effects offer good prospects for the medicinal applications of P . vulgaris . J Infect Dis, 2003 Nov 1, 188(9), 1382 - 93 Epub 2003 Oct 20. Protective efficacy of CAP18106-138-immunoglobulin G in sepsis; Warren HS et al.; Naturally present antibacterial proteins play an important role in innate host defense . A synthetic peptide mimicking the C-terminal lipopolysaccharide (LPS)-binding domain of rabbit cathelicidin CAP18 was coupled to immunoglobulin (Ig) G to create CAP18(106-138)-IgG, a construct that, in concentrations equimolar to those of peptide alone, binds and neutralizes LPS and kills multiple gram-negative bacterial strains . The protective efficacy of CAP18(106-138)-IgG was evaluated in a model of cecal ligation and puncture in mice . A single intravenous administration of 20 mg/kg CAP18(106-138)-IgG protected against mortality, compared with sham-coupled IgG (P<.03) . There was no protection offered by administration of equimolar peptide alone (P=.96) . There was a trend toward protection in C3H/HeJ mice that are minimally sensitive to LPS (P=.06), suggesting that direct detoxification of LPS was not the only mechanism of protection . Chemical or genetic coupling of antimicrobial peptides to IgG may be a means of using these peptides to treat infections. Bioorg Med Chem Lett, 2003 Nov 17, 13(22), 3993 - 6 Rational design of antimicrobial agents: antifungal activity of alk(en)yl dihydroxybenzoates and dihydroxyphenyl alkanoates; Nihei K et al.; A homologous series (C3-C14) of each alkyl 3,4- and 3,5-dihydroxybenzoates, and 3,4- and 3,5-dihydroxyphenyl alkanoates exhibit similar antifungal activity against Saccharomyces cerevisiae . Their nonyl derivatives exhibit the most potent antifungal activity against this yeast with the minimum fungicidal concentration (MFC) in the range between 12.5 and 50 microg/mL . In addition, various 3,4-dihydroxybenzoates, possessing different side chains, namely unsaturated, branched and alicyclic were synthesized and their activity was compared. Surg Infect (Larchmt), 2003 Fall, 4(3), 273 - 80 Prophylaxis of infection for elective colorectal surgery; Jimenez JC et al.; BACKGROUND: Influenced by the key results of the clinical trials conducted in the early 1970s by Condon, Nichols, and Gorbach, surgeons have adopted the routine use of mechanical bowel prep and antimicrobial prophylaxis prior to elective colorectal procedures as a widely established practice . Recent clinical trial data, however, led us to reexamine the benefits of mechanical bowel preparation, methods of antimicrobial prophylaxis and to assess the role of new, specific risk factors for surgical site infection after colorectal operations . METHODS: Pertinent studies on antimicrobial prophylaxis for elective colorectal surgery were identified from a Medline search of English language publications since 1966 . RESULTS: We found credible clinical trial data that mechanical bowel preparation prior to elective colorectal surgery may not be essential . Timing of the administration of prophylactic antimicrobials is often inaccurate in current practice and suggests the need for a long-acting, broad-spectrum agent that would deemphasize precision in time of preoperative infusion . New risk factors have been identified that increase infection after colorectal surgery, including patient core temperature and tissue oxygenation . Independent observers identify postoperative surgical site infection at a higher rate than physician self-reporting and should be incorporated into future clinical trials . CONCLUSION: The once settled area of antimicrobial prophylaxis for colorectal surgery is again controversial . Cooperative clinical trials will be needed to resolve key questions such as the efficacy for bowel preparation and how to obtain effective timing of antimicrobial prophylaxis. Infect Control Hosp Epidemiol, 2003 Oct, 24(10), 782 - 4 Light-activated antimicrobial coating for the continuous disinfection of surfaces; Wilson M; The ability of a photosensitizer-containing cellulose acetate film to kill bacteria was evaluated . Substantial kills were achieved following irradiation of the film with white light for up to 24 hours . Applying a photosensitizer-containing coating to surfaces could reduce the environmental load of pathogens, thus helping to prevent infectious disease transmission. Infect Control Hosp Epidemiol, 2003 Oct, 24(10), 762 - 4 Antimicrobial activity of glucoprotamin: a clinical study of a new disinfectant for instruments; Widmer AE et al.; OBJECTIVE: To determine the in vitro efficacy of glucoprotamin for the disinfection of instruments . DESIGN: Prospective observational study . SETTING: University women's hospital . METHODS: Instruments were immersed in saline solution after use, and glucoprotamin was added to a concentration of 1.5% before soaking for 60 minutes . Biocidal activity was determined by the difference in colony-forming units (CFU) on instruments before and after disinfection . RESULTS: One hundred thirty-seven instruments were collected during 10 days and exposed to a 1.5% dilution of glucoprotamin without prior washing . Bioburden before disinfection ranged from 2 x 10(5) to 7.1 x 10(7) CFU per instrument . Average bacterial killing was 5.98 log10 CFU +/- 0.48 under aerobic conditions and 6.75 log10 CFU +/- 0.54 under anaerobic conditions, despite the presence of large amounts of proteins on instruments that were frequently bloody . No vegetative bacteria were isolated in any sample after disinfection . CONCLUSION: This clinical study confirmed excellent in vitro efficacy of glucoprotamin without prior removal of proteins and debris. Otolaryngol Pol, 2003, 57(4), 581 - 6 {Bezold's abscess: a rare complication of otitis media}; Steczko A et al.; The authors present the case of a 21-year-old female in who, during the course of cholesteatoma, extracranial complications occurred twice in the form of Bezold's abscess . This type of the complication of otitis media occurs extremely rare . Medical literature has recorded about 20 cases of such complications . Due to commonly applied antibiotic therapies, extracranial and intracranial complications are rarely recorded in the course of otitis media, their mortality rate, however, amounts to a dozen or so per cent . The paper presents the way in witch the infection of otitis media spreads towards the neck . The authors stress the significance of computer tomography in diagnostic . Radical mastoidectomy and exploration of the neck were performed on the patient . Antibiotic regimens were based on antimicrobial sensitivity patterns . Presently, the patients is under constant laryngologist observation. Cell Tissue Res, 2004 Jan, 315(1), 59 - 70 Epub 2003 Oct 28.<