Pediatr Infect Dis J, 1995 Sep, 14(9), 731 - 7; quiz 738 What to expect from medical treatment of otitis media; Rosenfeld RM; 1 . To state the expected rates of spontaneous improvement for untreated acute otitis media (AOM), recurrent AOM, and otitis media with effusion (OME) . 2 . To state the expected impact of antibiotic therapy on AOM, recurrent AOM, and OME in terms of the number of children needed to be treated to cure or prevent a single episode . 3 . To explain why oral steroids are a promising, but unproven, treatment for OME . 4 . To update and modify expectations for medical treatment of otitis media based on meta-analysis of randomized clinical trials. J Hepatol, 1995 Sep, 23(3), 278 - 82 Focal destructive cholangiopathy associated with amoxycillin/clavulanic acid (Augmentin); Ryley NG et al.; Amoxycillin/clavulanic acid (Augmentin) has been widely used as a broad spectrum antibiotic since its introduction in 1981, since which time a number of reports of adverse hepatic reaction to the drug combination have been published . This paper describes five patients presenting with cholestatic illness within 8 weeks of a course of amoxycillin/clavulanic acid . The clinical picture indicated a direct link between the illness and the drug combination . Hepatic histology revealed a distinctive focal destructive cholangiopathy in all five patients, which has not previously been reported . Two also showed a granulomatous reaction, which has only previously been reported in one patient . Parallels are drawn with other diseases displaying bile duct destruction, and it is suggested that immunologically mediated drug-induced biliary damage may be involved . One of the five patients developed chronic liver disease with persistence of cholestatic liver biochemical tests, which has not previously been reported . The severity of the reaction and its prolonged course merit wider recognition of the possible adverse hepatic reaction to amoxycillin/clavulanic acid. Surg Neurol, 1995 Sep, 44(3), 265 - 9 Computerized tomography (CT) localized stereotactic craniotomy for excision of a bacterial intracranial aneurysm; Elowiz EH et al.; BACKGROUND: The treatment of bacterial intracranial aneurysms include long-term antibiotic therapy and surgical clipping or resection . Direct surgical approaches to these aneurysms are often complicated by their peripheral location . METHODS: We report the use of a computerized tomography (CT) localized stereotactic craniotomy for the excision of a ruptured peripheral bacterial intracranial aneurysm . RESULTS: The Leksell Steiner-Lindquist microsurgical guide, with its fiberoptic helium-neon laser, allowed for rapid isolation of the distal aneurysm with minimal cerebral dissection . Since the inflammatory lesion was well demonstrated on postcontrast CT scan, this modality, rather than angiography, was used for localization . CONCLUSIONS: In the future, stereotactic craniotomy may facilitate aggressive surgical therapy for infectious aneurysms previously thought not suitable for direct operative approach. Ophthal Plast Reconstr Surg, 1995 Sep, 11(3), 165 - 8 Pseudodacryocystitis arising from anterior ethmoiditis; Remulla HD et al.; The contiguous spread of inflammation from infected ethmoid sinuses to the surrounding tissues of the lacrimal drainage system can produce symptoms easily confused with acute dacryocystitis . We report the cases of two patients with presumed dacryocystitis whose patency of the lacrimal apparatus was established by probing, irrigation, and dacryocystography . Computerized tomography and magnetic resonance imaging demonstrated opacification of anterior ethmoid air cells adjacent to the region of the lacrimal sac . A greater awareness of this diagnostic possibility of pseudodacryocystitis arising from anterior ethmoiditis, together with improved noninvasive imaging techniques, will likely increase the observed incidence of this disease . This distinction is important since anterior ethmoidectomy, rather than dacryocystorhinostomy, is the treatment of choice when such pseudodacryocystitis proves unresponsive to antibiotic therapy . In misdiagnosed patients who undergo dacryocystorhinostomy, it is the coincidental limited anterior ethmoidectomy and not the lacrimal-nasal fistula that provides the cure. Scand J Plast Reconstr Surg Hand Surg, 1995 Sep, 29(3), 259 - 62 Penetration of flomoxef into human maxillary and mandibular bones; Igawa HH et al.; Penetration of flomoxef into the maxillary and mandibular bones was assayed clinically to provide data about its usefulness for the prevention of postoperative infection after maxillofacial surgery . Twenty-one patients undergoing maxillofacial surgery at our department were given flomoxef 2 g dissolved in 20 ml of physiological saline intravenously over 3 minutes during operation, and the serum, maxillary and mandibular concentrations were measured 1, 3, and 6 hours after injection by the band culture method using Escherichia coli 7437 as the indicator strain . The mean concentrations were 53.4, 16.1, and 2.6 micrograms/ml, respectively, in the serum, 17.6, 7.8, and 1.0 micrograms/g in maxillary bone, and 16.4, 4.2, and 0.9 micrograms/g in mandibular bone . The mean bone:serum ratios at 1, 3, and 6 hours were 33.0%, 48.2%, and 36.8%, respectively, for maxillary bone, and 30.7%, 26.2%, and 35.7% for mandibular bone . When compared with previously reported data on the bone:serum ratios in jaw of various other intravenous antibiotics, our results show that penetration of flomoxef into maxillary and mandibular bone is extremely high . As all the intramaxillary and intramandibular concentrations exceed its MIC80 values against clinical isolates of bacteria frequently isolated in cases of infection in the oral and maxillofacial region, it is apparent that one intravenous shot of flomoxef 2 g allows penetration of the drug into the maxillary and mandibular bones at effective concentrations . Flomoxef is therefore potentially useful for the prevention and treatment of infections in the oral and maxillofacial region, as it has excellent penetration into the maxillary and mandibular bones. J Pharm Sci, 1995 Sep, 84(9), 1094 - 100 Distribution of free and liposomal annamycin within human plasma is regulated by plasma triglyceride concentrations but not by lipid transfer protein; Wasan KM et al.; Annamycin (Ann) is a lipophilic and non-cross-resistant anthracycline antibiotic currently in clinical development as a liposomal formulation (L-Ann) composed of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylglycerol (DMPG) . Previous studies have demonstrated that the incorporation of Ann into these liposomes prolongs its terminal serum half-life and increases the tumor levels of the drug . However, an explanation for the altered pharmacokinetics and pharmacodynamics of doxorubicin and Ann when entrapped into these multilamellar lipid vesicles remains unknown . Since the distribution of lipophilic compounds within plasma lipoproteins has been shown to influence the pharmacokinetics and organ distribution of a number of lipophilic compounds and this distribution appears to be regulated by lipid transfer protein (LTP), we studied the distribution of Ann and L-Ann among plasma lipoproteins and the influence of LTP on the distribution of Ann and L-Ann among plasma lipoproteins . Our results concluded that when Ann was incorporated into liposomes composed of DMPC and DMPG, over 65% of the initial Ann concentration would distribute into the high density lipoprotein (HDL) fraction and that free Ann and L-Ann distribution within human plasma was independent of LTP activity . In addition, we observed that the increase in total plasma triglyceride (TG) concentrations (through the increase of very low-density lipoproteins (VLDL)) resulted in the increase distribution of Ann and L-Ann within the TG-rich VLDL fraction . However, increasing the VLDL core TG/cholesterol ratio decreased Ann distribution into VLDL . These findings suggest that initial Ann distribution is regulated by a mechanism that does not involve LTP, but through its interaction with plasma VLDL-TG.(ABSTRACT TRUNCATED AT 250 WORDS) Genetics, 1995 Sep, 141(1), 25 - 32 Genetic analysis of the colicin V secretion pathway; Zhang LH et al.; Colicin V (ColV) is peptide antibiotic secreted by Escherichia coli through a dedicated exporter composed of three proteins, CvaA, CvaB, and TolC . ColV secretion is independent of the E . coli general secretory pathway (Sec) but requires an N-terminal export signal specific for the CvaAB/TolC exporter . ColV secretion was characterized using genetic and biochemical methods . When the ColV N-terminal extension is replaced with the OmpA signal sequence, the Sec system can localize ColV to the periplasm . Periplasmic ColV is lethal to cells lacking the ColV immunity protein, Cvi . Based on this result, a genetic assay was designed to monitor for the presence of periplasmic ColV during normal CvaAB/TolC mediated secretion . Results indicate that low levels of ColV may be present in the periplasm during secretion . Precursor and mature ColV were also characterized from the wild-type system and in various exporter mutant backgrounds using immunoprecipitation . ColV processing is rapid in wild-type cells, and CvaA and CvaB are critical for processing to occur . In contrast, processing occurs normally, albeit more slowly, in a TolC mutant. J Vet Intern Med, 1995 Sep-Oct, 9(5), 357 - 60 Monoclonal gammopathy in a dog with chronic pyoderma; Burkhard MJ et al.; A monoclonal gammopathy composed of immunoglobulin G, with concurrent light-chain proteinuria and generalized lymph node plasmacytosis, was associated with chronic pyoderma in a dog . A uniform population of plasma cells was observed cytologically and histologically in multiple lymph node specimens . A diagnosis of monoclonal gammopathy of unknown significance was eventually made by exclusion of other known causes of monoclonal gammopathy, resolution after antibiotic therapy, and no evidence of lymphoproliferative disease after 11 months of follow-up and subsequent necropsy . This report expands the diagnostic considerations for monoclonal gammopathies in the dog. Nippon Kyobu Geka Gakkai Zasshi, 1995 Sep, 43(9), 1549 - 52 {Thoracoscopic debridement for acute empyema}; Yagi K et al.; Thoracoscopic debridement for acute empyema was successfully performed in three patients who were refractory to closed drainage, irrigation and antibiotic therapy . In two patients anaerobic organisms were isolated from the pus . None of the patients had bronchopleural fistula . All patients were relieved of fever promptly after surgery . Operative invasion was minimal, and postoperative lung function was well maintained one month after the operation . If empyema is in the fibrinopurulent phase and does not respond to pleural drainage, thoracoscopic debridement may be indicated before more aggressive therapy. J Int Med Res, 1995 Sep-Oct, 23(5), 369 - 76 Open randomized study comparing doxycycline and co-amoxiclav in the treatment of acute suppurative tracheobronchitis in adults . The Collaborative Group of the Centre Universitaire de Medécine Générale de L'Université Libre de Bruxelles (CUMG-ULB) Investigators; Sternon J; Doxycycline and co-amoxiclav were compared in a randomized clinical trial involving adult patients with acute suppurative tracheobronchitis . Patients were treated for 5 to 10 days with either antibiotic following three schemes: co-amoxiclav 500 mg three times daily, or doxycycline 200 mg on day 1 followed by 100 mg daily, or 200 mg daily . Assessment after 5-9 days was based only on clinical parameters . Patients with inadequate response to the initial treatment were crossed over to the alternative antibiotic . Of the 210 patients enrolled, 206 were available for evaluation of efficacy . Both antibiotic regimens proved equally efficacious, with rates of clinical response (cure or improvement) of 89% and 91% for doxycycline and coamoxiclav, respectively . Patients who were crossed over to the alternative antibiotic had a significantly lower cure rate after their second course of antibiotics (22% compared with 70%) . Adverse effects, most often of gastro-intestinal origin, were more common in the co-amoxiclav group than in the doxycycline-treated group, but rarely caused cessation of treatment. J Hand Surg {Am}, 1995 Sep, 20(5), 868 - 72 Management of finger ulcers in scleroderma; Ward WA et al.; Twelve patients (15 hands) with documented scleroderma and chronic nonhealing digital ulcers were followed for their response to nonoperative and operative treatment . The patients were initially managed with nifedipine, biofeedback, digital xylocaine blockade, and silver sulfadiazine topical ointment and cessation of all vasoconstrictive agents . Ulcerations healed in 6 of 15 hands and remained healed at a 2-year follow-up examination . The remaining nine hands in seven patients failed nonoperative treatment and underwent a palmar digital sympathectomy . These chronic digital ulcerations healed within 6 weeks after surgery . After a 26- to 64-month follow-up period, six of the nine hands remained free of all digital ulcerations . Two patients (three hands) had partial recurrence of the ulceration . Digital sympathectomy can be an effective procedure for treating nonhealing digital ulcers in scleroderma patients after nonoperative treatment has failed . Significant vaso-occlusive disease is likely to be present in these patients, as demonstrated by arteriography . Our initial approach is cessation of all vasoconstricting agents, nifedipine biofeedback, and local antibiotic ointment . Wrist blocks with xylocaine and marcaine are offered if these modalities fail . If these methods do not result in healing of the ulcer within 12 weeks, then digital sympathectomy is considered. Am J Respir Crit Care Med, 1995 Sep, 152(3), 1103 - 6 Site-directed bronchoalveolar lavage and transbronchial biopsy in HIV-infected patients with pneumonia; Cadranel J et al.; We have assessed the diagnostic value of site-directed bronchoalveolar lavage (BAL) and combined transbronchial biopsy (TBB) in 29 HIV-infected patients with localized pneumonia, in whom a previous BAL was nondiagnostic and in whom improvement did not occur with empiric antibiotic therapy . All patients but three had a CD4 cell count < 100/microliters . A definite diagnosis could be reached in 26 of 29 (90%) individuals, including 24 pathogens . Neither the radiologic pattern nor the type of Pneumocystis carinii (PC) prophylaxis could predict the positivity of either one of these two diagnostic procedures . Site-directed BAL alone allowed a diagnosis in infection in eight (28%) cases . TBB alone led to diagnosis in eight (28%) cases, including three PC and two toxoplasma gondii, undiagnosed by the site-directed BAL . Both techniques were positive and in agreement in 10 (34%) cases . The majority of the diagnosis led to a specific treatment . Therefore, the patients' survival was positively altered by the procedure . In conclusion, the performance of site-directed BAL and combined TBB markedly optimizes the diagnostic yield of each of these procedures performed separately in HIV-infected patients with localized pneumonia. Am J Respir Crit Care Med, 1995 Sep, 152(3), 1072 - 8 Dynamics of respiratory tract colonization by Branhamella catarrhalis in bronchiectasis; Klingman KL et al.; Branhamella catarrhalis is increasingly recognized as a lower respiratory tract pathogen, particularly in chronic lung diseases . This project defines a population of patients in whom the dynamics of colonization and infection caused by this organism could be studied . A method employing pulsed field gel electrophoresis (PFGE) of genomic DNA was developed . Twenty-eight patients with bronchiectasis followed prospectively for 26.8 mo (mean) were seen monthly or bimonthly and at the time of a purulent exacerbation . Quantitative bacterial cultures were performed on sputum obtained at each visit . Six of 28 had B . catarrhalis isolated repeatedly . Viable numbers of B . catarrhalis were similar to other bacterial pathogens . Restriction fragment length polymorphism (RFLP) analysis of chromosomal DNA using PFGE was performed on 37 of the 47 isolates recovered . Each patient was colonized by two to four strains with different RFLP patterns . Duration of colonization by the same strain was 2.3 mo (mean) . Strain acquisition did not correlate with exacerbation, antibiotic therapy, or season . We conclude that (1) a subset of bronchiectatic patients is colonized with B . catarrhalis, (2) RFLP is a sensitive tool to study strain acquisition, and (3) acquisition and clearance of B . catarrhalis from the respiratory tract is a dynamic process. Am J Gastroenterol, 1995 Sep, 90(9), 1407 - 10 Limited efficacy of omeprazole-based dual and triple therapy for Helicobacter pylori: a randomized trial employing "optimal" dosing; Laine L et al.; OBJECTIVES: To evaluate the efficacy and side effects of dual omeprazole/amoxicillin therapy for Helicobacter pylori given in "optimal" fashion (omeprazole twice a 3 g of amoxicillin daily, drugs started concurrently, 2 wk of therapy) and to assess the utility of adding a second antibiotic, tetracyline . METHODS: Sixty healthy volunteers with H . pylori infection documented by 13C-urea breath test were randomly assigned to receive 2 wk of therapy with either 1) omeprazole 20 mg b.i.d . and amoxicillin 1 g t.i.d . (OA), or 2) OA plus tetracycline 500 mg t.i.d . (OAT) . Patients returned after 2 wk for pill count and clinical assessment, and 13C-urea breath test was repeated 4 wk after the end of therapy . RESULTS: H . pylori was eradicated in 15 (50%) of 30 patients receiving OA therapy and in nine (30%) of 30 given OAT (p = 0.19) . Side effects occurred in five (17%) patients in the OA group {two (7%) discontinued therapy due to side effects} and eight (27%) of the OAT group {three (10%) stopped therapy due to side effects} . Good compliance (> 80% of prescribed study drugs taken) was seen in 87% of each group, and eradication rates were 54% and 35% among patients with good compliance in the OA and OAT groups (p = 0.26) . CONCLUSIONS: Dual therapy with omeprazole and amoxicillin, when given in "optimal" fashion, had limited efficacy, with an eradication rate of 50% . The addition of tetracycline to the dual therapy did not improve the rate of cure . Because virtually all of our subjects were from minority groups, with over three-fourths Hispanic, we speculate that differences in H . pylori strains or host factors may explain, at least in part, the discrepancy between our results and those in Northern European populations. Urology, 1995 Sep, 46(3), 370 - 7 Reversion of human prostate tumorigenic growth by azatyrosine; Benoit RM et al.; OBJECTIVES . Azatyrosine, an antibiotic isolated from a Streptomyces species, has been previously shown to have antitumor activity against ras- and neu-transformed fibroblasts and human epithelial cells . In this study, we investigated the effect of azatyrosine on human prostate cancer cell growth and the reversion potential of this antibiotic on prostate tumorigenic cell lines . METHODS . Three androgen-independent human prostate cancer cell lines (TSU-Prl, DU-145, and PC-3) were cultured in the presence of azatyrosine and their growth rates were determined over a 7-day period . Following exhaustive treatment with azatyrosine for 5 weeks, three azatyrosine-resistant colonies were cloned from the PC-3 cell line and were subsequently established as stable cell lines . The growth characteristics of these azatyrosine-resistant clones were examined both in vitro and in vivo to establish their "potentially revertant" profiles . RESULTS . Incubation with azatyrosine (for 7 days) resulted in greater than 95% in vitro growth inhibition of the three parental prostate cancer cell lines . Analysis of the biologic properties of these azatyrosine-resistant cell lines revealed: (1) a significant reduction in in vitro growth rates; (2) a decreased rate of DNA synthesis as measured by thymidine uptake; and (3) a decreased ability for colony formation in soft agar . Moreover all three azatyrosine-resistant clones exhibited suppressed tumorigenicity in severe combined immunodeficient (SCID) mice when compared with the parental cell line . An important observation was that one revertant clone demonstrated complete loss of tumorigenicity . On the basis of this biologic behavior, these cell lines were characterized as revertants . Cytogenetic analysis revealed gross chromosomal differences between the revertant clones and the parental cell line . Northern hybridization analysis demonstrated elevated expression of the K-rev-1 and bcl-2 but not the rrg mRNA transcripts in the revertant cell lines . CONCLUSIONS . These results suggest that azatyrosine inhibits prostate tumorigenic growth; it has a high reversion efficiency on human prostate cancer cells; and the K-rev-1 suppressor gene and the bcl-2 proto-oncogene could be potentially involved in the reversion mechanism mediated by azatyrosine . This reversion of prostate cancer cells to an apparently nontumorigenic phenotype points to a potentially significant therapeutic role for azatyrosine in the treatment of advanced prostate cancer. Cell Immunol, 1995 Sep, 164(2), 234 - 9 Stably transfected antisense granzyme B and perforin constructs inhibit human granule-mediated lytic ability; Bochan MR et al.; In human NK cells and CTL it has been shown that release of lytic molecules is, at least in part, responsible for the lysis of target cells (TC) . Of the various types of molecules thought to be involved in cell-mediated cytotoxicity (CMC), perforin and the serine proteases (granzymes A and B) are the best described . Using mammalian expression vectors (pRSV-neo and pSV2-neo), antisense constructs for perforin and granzyme B were independently electroporated into YT-INDY, a human non-MHC-restricted, IL-2-independent, cytotoxic lymphocyte . Transfected YT-INDY was then selected for expression of the plasmid by antibiotic G418 resistance . The presence of plasmid was confirmed by detection of the integrated plasmid G418 resistance gene using PCR . The presence of antisense perforin in YT-INDY (YT-xPFP) inhibited lytic ability by > 95% compared to YT-INDY transfected with plasmid alone or plasmid with unrelated antisense (YT-neo, YT-ctrl, respectively) . Likewise, the presence of antisense GrB (YT-xGrB) inhibited the lytic ability of YT-INDY by > 95% . Western analysis revealed a 30% decrease in the level of perforin and a 55% decrease in granzyme B protein levels compared to YT-neo . Northern analysis using oligo probes complementary to perforin and granzyme B mRNA showed a decrease in their respective message levels . In conclusion, stably transfected antisense constructs for perforin and granzyme B essentially eliminated the lytic ability of YT-INDY . These results strongly indicate that both perforin and granzyme B are required by this human cytotoxic lymphocyte for effective TC lysis. Obstet Gynecol, 1995 Sep, 86(3), 392 - 5 Latency period after preterm premature rupture of membranes: a comparison of ampicillin with and without sulbactam; Lewis DF et al.; OBJECTIVE: To compare ampicillin with and without sulbactam with respect to the effect on the latency period after preterm premature rupture of membranes (PROM) . METHODS: Patients with PROM at 25-35 weeks' gestation were offered participation in a randomized blinded trial comparing ampicillin-sulbactam with ampicillin . Evaluations for cervical pathogens were performed on admission and patients were followed-up with daily maternal and fetal evaluation . Maternal and neonatal outcomes were analyzed using indicated techniques . RESULTS: Fifty-three women were studied, with 25 receiving ampicillin-sulbactam and 28 receiving ampicillin . The ampicillin-sulbactam group had a significantly longer latency period (433 +/- 625 versus 143 +/- 165 hours, P = .03) and significantly fewer neonatal complications (five versus 20, P < .001) . Although no neonatal infectious complications were observed in sulbactam-treated cases, there were four cases of neonatal sepsis and two of neonatal pneumonia in the ampicillin group . Also, significantly more neonates in the ampicillin group required prolonged oxygen and ventilatory support . There was no significant difference in maternal morbidity . CONCLUSIONS: In our population with preterm PROM, a broad-spectrum antibiotic that provides anaerobic coverage appears to extend latency and decrease neonatal morbidity without increasing adverse maternal outcome. Infect Immun, 1995 Sep, 63(9), 3479 - 83 Identification of a possible cytadherence regulatory locus in Mycoplasma pneumoniae; Hedreyda CT et al.; Transposon mutagenesis was used to analyze Mycoplasma pneumoniae cytadherence . Mycoplasmas were electroporated with Tn4001, and transformants were identified by antibiotic selection using gentamicin . The resulting colonies were screened for hemadsorption (HA) as an indicator for cytadherence . Six HA- colonies from independent transformations were isolated, filter cloned, and characterized in more detail . Southern hybridization analysis revealed that all six transposon insertions mapped to the same 252-kbp ApaI fragment and 19.5-kbp XhoI fragment . More detailed analysis localized the insertion to two adjacent EcoRI fragments . This site is distinct from the locus containing the genes for the high-molecular weight cytadherence-accessory proteins HMW1 and HMW3, and yet these proteins were absent from the protein profiles of all six transformants . To determine if transposon insertion was responsible for the HA- phenotype, reversion frequencies of the transformants were assessed after passage in the presence of antibiotic selection . In contrast to a spontaneously arising HMW-deficient variant, which reverted to an HA+ phenotype readily, no HA+ revertants were identified for any of the six transformants . These observations suggest that a potential regulatory locus that may be important in the expression of the HMW cytadherence-accessory proteins has been identified. J Pediatr Orthop, 1995 Sep-Oct, 15(5), 666 - 71 Toxic shock syndrome as a complication of orthopaedic surgery; Grimes J et al.; Toxic shock syndrome (TSS) was initially described by Todd et al . in 1978 . TSS as a complication of orthopaedic surgery was reported in 1984 . There have been previously a total of nine cases of TSS reported in orthopaedic patients . These patients presented at an average of 13 days postoperatively compared to 2 days for general surgical patients . Patients with external fixators, however, presented an average of 25 days postoperatively . Menstrual TSS and nonmenstrual TSS present similarly; however, the fatality rate is reported as 10 and 50%, respectively . There was a 27% case fatality rate in orthopaedic patients . Because TSS is not a septicemia but a toxemia, the treatment depends on aggressive hemodynamic stabilization rather than antibiotic therapy . The classical presentation of TSS is not often seen in patients with TSS complicating orthopaedic surgery . Wounds rarely have any signs of infection . This presentation may be even more difficult to identify due to the occasionally long latency period between surgery and the development of TSS . It appears that external fixators may be left in place if there are no signs of infection . This requires further study. J Antibiot (Tokyo), 1995 Sep, 48(9), 1021 - 6 Inhibition of the association with nuclear matrix of pRB, p70 and p40 proteins along with the specific suppression of c-MYC expression by geldanamycin, an inhibitor of Src tyrosine kinase; Yamaki H et al.; Geldanamycin is an antibiotic that preferentially inhibits G1/S transition and causes G2/M arrest in human leukemia HL-60 cells . With it, we selectively inhibited recombinant Src tyrosine kinase without significantly inhibiting protein kinase A . The perturbation of cell cycling by geldanamycin was accompanied by marked suppression of c-MYC expression . In contrast to this, pRB expression was remarkably enhanced by geldanamycin . In the untreated HL-60 cells, c-MYC was apparently enriched in nuclear matrix preparation, and significant amounts of hyperphosphorylated pRB, p70 and p40 proteins were observed to associated with the nuclear matrix . The amounts of these proteins associated with the nuclear matrix, however, were markedly decreased by treatment with geldanamycin . This finding suggests that the association of c-MYC, hyperphosphorylated pRB, p70 and p40 proteins with the nuclear matrix is essential in cell cycling, especially in G1/S and G2/M progressions, and that this association is a part of signal transduction pathway in Src kinase activation. Int J Oral Maxillofac Implants, 1995 Sep-Oct, 10(5), 609 - 13 Immediate implants placed into infected sites: a clinical report; Novaes Junior AB et al.; Placement of immediate implants is a routine clinical procedure . However, certain clinical conditions, especially the presence of infected sites, are considered to be contraindications for the immediate implant . Based on clinical experience, it is proposed that if certain preoperative and postoperative steps are carefully followed and meticulous debridement of the alveolus is done during the surgical procedure, immediate implants can be successfully placed into chronically infected sites . The advantages of this procedure are discussed. Fortschr Neurol Psychiatr, 1995 Sep, 63(9), 358 - 62 {The value of clinical and chemical laboratory follow-up parameters in neuroborreliosis}; Koch J et al.; Whereas the diagnosis of acute neuroborreliosis by considering clinical and cerebrospinal fluid parameters is very reliable chronic neuroborreliosis is an excluding diagnosis . The clinical symptoms are uncharacteristic, and there is no reliable laboratory test permitting a safe diagnosis . Serological evidence of antibodies is no sign of activity of disease . Development of chronic infection after adequate treatment of acute neuroborreliosis seems to be very rare . We reinvestigated 15 patients half a year after antibiotic therapy of acute neuroborreliosis with regard to clinical and laboratory parameters . Most patients had a continuous intrathecal IgG antibody production against Borrelia burgdorferi, whereas no clinical signs of chronic neuroborreliosis existed . The antibody production against Borrelia burgdorferi must not be regarded as a sign of chronic infection. Adv Wound Care, 1995 Sep-Oct, 8(5), 58 - 9 Infection and the impact on cost effectiveness in wound care; Song C; The financial impact of infections in treating persons with traumatic injuries at a hospital in Johannesburg, South Africa, are described . Principals of the management of infected wounds are reviewed . Factors that influence the choice of reconstructive options are given . The cost of using various dressings, particularly occlusive dressings, in the management of infected wounds is explored . This real problem in the wound care discipline commands due respect, and the literature is testimony to this . Central to the management of this potential complication in surgery is the oft-cited question of which prophylactic antibiotic to administer . The issue is so important in fields such as cardiothoracic surgery, hip joint replacement, and intracranial surgery, that the thought of not administering prophylactic antibiotics is not entertained. World J Surg, 1995 Sep-Oct, 19(5), 680 - 6; discussion 686 Comparison of cefotaxime plus metronidazole versus cefoxitin for prevention of wound infection after abdominal surgery; Kow L et al.; In a randomized prospective stratified trial consisting of 1010 patients undergoing abdominal surgery involving the viscera, the efficacy of cefotaxime plus metronidazole was compared to cefoxitin for preventing wound infection . The efficacy of a single dose of antibiotics versus three doses over 24 hours was also evaluated . This study demonstrated that a single-dose antibiotic regimen was as effective as a multiple-dose regimen in the prophylaxis of wound infections following abdominal surgery . In addition it demonstrated that the cefotaxime plus metronidazole regimen is comparable to that of cefoxitin and is more cost-effective . It is concluded that a single dose of cefotaxime plus metronidazole provides effective prophylaxis against postoperative wound infections following abdominal surgery. Mutat Res, 1995 Sep, 348(1), 1 - 6 The pattern of adriamycin-induced mutations in V-E5 Chinese hamster cells with chromosomal instability; Helbig R et al.; The V-E5 cell line, a mutant V79 Chinese hamster cell line, was used to study the effect of chromosomal instability on the spectrum of gene mutations and chromosome aberrations induced by the anthracycline antibiotic adriamycin (AM) . V-E5 cells showed hypersensitivity to the cytotoxic effects of AM when compared to the parental cell line . AM caused both, chromosome-type aberrations and chromatid-type aberrations in V-E5 cells . Under the same experimental conditions, gene mutations were induced at the hprt locus which mainly represented deletion mutations . The spectrum of AM-induced chromosomal aberrations and gene mutations did not show any peculiarities in comparison to normal V79 cells . It is concluded that the genomic instability in V-E5 cells does not influence the pathways leading to chromosome aberrations and gene mutations after AM treatment. Heredity, 1995 Sep, 75 ( Pt 3), 320 - 6 Wolbachia and cytoplasmic incompatibility in mycophagous Drosophila and their relatives; Werren JH et al.; Bacterial symbionts belonging to the genus Wolbachia are associated with postzygotic reproductive incompatibility in a number of insect species . Using polymerase chain reaction (PCR) amplification of bacterial gene sequences, strains from 10 species belonging to the closely related quinaria, testacea and tripunctata groups of Drosophila were screened for the presence of Wolbachia in their reproductive tissues . Those screened included the mycophagous species D . falleni, D . recens, D . phalerata, D . testacea, D . neotestacea, D . orientacea, D . putrida and D . tripunctata, and the nonmycophagous species D . palustris and D . quinaria . Two species, D . recens and D . orientacea, were found to be infected with Wolbachia . Subsequent tests of four additional strains of D . recens found all to be infected with the bacteria . It was established that these bacteria cause partial cytoplasmic incompatibility in D . recens by antibiotic curing followed by crosses between cured and uncured strains . Curing was confirmed by a PCR assay . Although most species of insects shown to be infected with Wolbachia are cosmopolitan and/or have undergone recent range expansion in association with human activity, D . recens and D . orientacea are endemic species with specialized ecological habits . Preliminary molecular phylogenetic analysis indicates that, among the species we examined, D . quinaria is most closely related to D . recens . To determine whether the bacteria are involved in reproductive isolation between these two species, reciprocal crosses were carried out between D . quinaria and both infected and uninfected (cured) strains of D . recens . Although these species did mate with each other, all interspecific crosses failed to yield hybrid progeny, indicating that the bacteria are not responsible for reproductive incompatibility between these species. Radiographics, 1995 Sep, 15(5), 1147 - 54 SAPHO syndrome; Cotten A et al.; Palmoplantar pustulosis and severe acne are sometimes associated with peculiar aseptic skeletal conditions, but such skeletal lesions can be found without skin lesions . The term SAPHO syndrome has been coined for this cluster of manifestations . (The acronym SAPHO refers to synovitis, acne, palmoplantar pustulosis, hyperostosis, and osteitis.) The most common site of the disease is the upper anterior chest wall, characterized by predominantly osteosclerotic lesions, hyperostosis, and arthritis of the adjacent joints . Osteosclerosis of the vertebral bodies, hyperostosis, and erosions of the vertebral plates can be encountered . Unilateral sacroiliitis is frequently observed . Long bone involvement consists of osteosclerosis or osteolysis with periosteal new bone formation . Peripheral arthritis can be present but is rarely associated with joint destruction . The pathogenesis of this syndrome remains unknown, but a link with seronegative spondyloarthropathies is probable . Radiologists should be aware of this unusual syndrome to avoid misdiagnosis (eg, tumor, infection), unnecessary surgery, and antibiotic therapy. Handchir Mikrochir Plast Chir, 1995 Sep, 27(5), 242 - 6 {Lyme borreliosis in hand surgery . A case report}; Ebert B et al.; The clinical courses of Borrelia burgdorferi infections may show such variety, that diagnostic problems arise . On the other hand, early antibiotic therapy is necessary in order to prevent late-term complications . In this article, we present an exceptional case of a long-term documentation of Lyme-disease which was not diagnosed until an acrodermatitis chronica atrophicans had developed . Whether the manifestation of bilateral carpal tunnel syndrome is connected with Lyme borreliosis is yet to be clarified. Geburtshilfe Frauenheilkd, 1995 Sep, 55(9), 510 - 7 {Chlamydia infections in gynecology and obstetrics}; Dieterle S; Urogenital infections with Chlamydia trachomatis belong to the most prevalent sexual transmitted diseases worldwide . In women, Chlamydia trachomatis can cause an infection of the cervix, the urethra, the endometrium and the Fallopian tubes . As potential sequelae, tubal infertility and ectopic pregnancies are associated with urogenital infections caused by this pathogen . An infection of the cervix in pregnancy can lead to neonatal and maternal complications . Therefore, by April 1st, 1995 a cervical swab for Chlamydia trachomatis has been included in the German antenatal care guide lines . The significance of these infections in health care is in contrast to its often hardly symptomatic or asymptomatic course . New diagnostic methods facilitate the detection of the pathogen and allow a specific antibiotic therapy . The aim of this review is a presentation of the clinical significance, diagnosis and therapy of urogenital infections with Chlamydia trachomatis in obstetrics and gynaecology to contribute to the prevention of potentially severe sequelae. Arzneimittelforschung, 1995 Sep, 45(9), 1013 - 7 Experimental studies on the influence of surfactants on intestinal absorption of drugs . Cefadroxil as model drug and sodium lauryl sulfate as model surfactant: studies in rat duodenum; Sancho-Chust V et al.; The effect of sodium lauryl sulfate (CAS 151-21-3) on the duodenal absorption of cefadroxil (CAS 50370-12-2) has been investigated with the aid of a classical rat gut in situ preparation . Both compounds were entirely compatible in working solutions . Cefadroxil was found to be very stable and only slightly solubilized in the micellar phase . The apparent first-order absorption rate constants for the free antibiotic fraction were determined in free solution, and in the presence of variable surfactant concentration in luminal fluid . A functional interpretation of these data, based both on the law of mass action and the complete noncompetitive transport inhibition equations, showed that the surfactant acts as a nonspecific inhibitor of the carrier-mediated absorption of the antibiotic, but also as an enhancer of its passive absorption component . The net result was an outstanding reduction in the absorption capacity of cefadroxil when it was perfused at 0.1 mg/ml, i.e . far from its carrier saturation (from 3.0 h-1 in free solution to 2.0(-1) at high surfactant concentration, with a minimum of about 1.4 h-1 in the presence of the surfactant at 0.5 mg/mg in duodenal fluid) . When cefadroxil was perfused at 10.0 mg/ml, i.e . with its carrier-mediated transport beyond the saturation, the net result was a progressively enhanced absorption (ranging from about 0.9 h-1 in free solution to 2.0 h-1 at high surfactant concentration).(ABSTRACT TRUNCATED AT 250 WORDS) Acta Med Port, 1995 Sep, 8(9), 493 - 6 {The usefulness of bronchofibroscopy in the diagnosis of lung neoplasms in patients with protracted pneumonia}; Gloria C et al.; Fiber-optic bronchoscopy is commonly performed in patients with non resolving pneumonia to exclude endobronchial neoplastic tumours . Radiographic resolution of community-acquired pneumonia is variable, depending on several factors, as the causative agent or host dependent factors . Therefore, the decision to perform a bronchoscopy is sometimes empirical . To describe our experience in this subject we reviewed the clinical registrations and the bronchoscopy protocols of 123 consecutive patients with community-acquired pneumonia that did not show significant radiographic resolution after at least ten days of antibiotic therapy . A histological diagnosis of malignant neoplasia was obtained in 5.6% of the cases . All patients were males, more than 55 years old and heavy smokers (more than 40 pack/year) . The comparison between this risk group and the other patients showed statistically significant differences in age and tobacco consumption . Symptom duration, haemoglobin, leukocytes, sedimentation rate, renal or hepatic tests were not significantly different in both groups . We recommend that fiber-optic bronchoscopy must be performed early in heavy smokers, patients over 55 years of age with slow or non resolving pneumonia . In non-smokers or younger patients, it should only be performed after 4 to 8 weeks, unless clinical symptoms justify an earlier observation. Mol Immunol, 1995 Sep, 32(13), 947 - 55 Activation-induced apoptosis in Jurkat cells through a myc-independent mechanism; Ruiz-Ruiz MC et al.; Apoptosis can be induced in the human leukemic T-cell line Jurkat when these cells are stimulated by several known T-cell activators . Among the stimuli that activate Jurkat cells, calcium ionophore A23187, phytohemagglutinin and cross-linked monoclonal antibody anti-CD3 are the best inducers of apoptosis . The activator of protein kinase C phorbol-12,13-dibutyrate causes a rapid but transient stimulation of DNA fragmentation and cell death, and soluble monoclonal antibody anti-CD3 has no effect . Furthermore, apoptosis is delayed when Jurkat cells are stimulated simultaneously with calcium ionophore and phorbol ester . We have analysed the mechanism underlying the induction of apoptosis by these agents and found that down-regulation of c-myc expression by pretreatment with the DNA binding antibiotic mithramycin, an inhibitor of c-myc transcription, does not prevent the activation of the apoptotic process . In the light of these results we can conclude that in these leukemic T-cells, activation of apoptosis may occur by a mechanism independent of c-myc expression. Nippon Rinsho, 1995 Sep, 53(9), 2340 - 9 {New anti-HIV drug which binds the oligosaccharides of HIV envelope glycoprotein}; Mizuochi T et al.; The virion surface of the human immunodeficiency virus (HIV-1) is covered with an envelope glycoprotein gp120 . Study of the oligosaccharide structures of gp120 suggests that the high mannose type of oligosaccharides are essential for HIV-1 infection . Pradimicin A, an antifungal antibiotic isolated from Actinomadura hibisca, and the derivative BMY-28864 have the ability to inhibit HIV-1 infection in vitro . The inhibitory effect was suppressed by addition of high mannose type oligosaccharides of gp120 . BMY-28864 bound directly to gp120, mannose-BSA, and neoglycolipids containing high mannose type oligosaccharides but not to natural mammalian glycoproteins . The binding was Ca2+ dependent and was inhibited by mannose . BMY-28864 is a unique carbohydrate-binding antibiotic which has never been reported . It is possible to block HIV-1 infection by targeting oligosaccharide chains of the envelope glycoprotein. Nippon Rinsho, 1995 Sep, 53(9), 2160 - 7 {Enzyme labeling methods and it's specificities}; Kambegawa A; Enzyme labeled antigen for use in ELISA of Hapten (steroids, prostanoid, carbohydrate, nucleic acid, peptide, herbicide, insecticide and antibiotic) have usually been prepared by condensation of carboxy group of hapten with amino groups of lysine residue in enzyme . The horseradish peroxidase (HRP) is best suitable as labeling enzyme, therefore it is small molecular, and substrate turnover is much higher compared to the other enzymes . The mixed anhydride and carbodiimide methods have mainly been used the preparation of hapten conjugate BSA, but not satisfactory for enzyme labeling . The N-hydroxysuccinimide ester (NHS: active ester) method is satisfactory with respect to reproducibility and sensitivity . The sensitivity is related to the bridging phenomenon: One of the disadvantages of the homologous labels is that the antibody shows an affinity not only for the Hapten but also for the bridge which connects the Hapten to carrier protein . We have developed a sensitive bridge heterologous EIA for progesterone (P) using geometrical isomers of P-3 (E/Z) (O-carboxymethyl) oxime-N-hydroxysuccinimide esters {ef Ab of P-3 (E) CMO-BSA/P-3 (Z) CMO-HRP}3) . The sensitivity of heterologous proved to be higher than a homologous EIA or a conventional RIA . It seem like that a 1:1 steroid-enzyme conjugate is suitable for obtaining a high sensitivity . The avidin-biotin (AB) system provides great versatility, since by conjugation with an appropriate label, the AB assay can be used with any chosen detector . Furthermore, IgG can be labels with biotin without significantly influencing their immunological activity.(ABSTRACT TRUNCATED AT 250 WORDS) Mol Cell Endocrinol, 1995 Aug 30, 113(1), 73 - 81 Wortmannin and LY294002 inhibit the insulin-induced down-regulation of IRS-1 in 3T3-L1 adipocytes; Smith LK et al.; The insulin receptor substrate-1 (IRS-1) is expressed in 3T3-L1 adipocytes and is involved in at least some insulin responses, notably mitogenesis . Chronic exposure to insulin down regulates IRS-1 in these cells by stimulating its degradation (Rice, K.M., Turnbow, M.A . and Garner, C.W . (1993) Biochem . Biophys . Res . Commun . 190, 961-967) . This insulin response was completely inhibited by wortmannin and LY294002 (2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one), two inhibitors of phosphatidylinositol 3-kinase (PI 3-kinase) . Neither wortmannin nor LY294002 had any effect on the calcium-dependent degradation of IRS-1 in vitro nor did they inhibit the phosphorylation of IRS-1 in vitro . In addition, neomycin, a cationic aminoglycoside antibiotic that binds to phosphoinositides, inhibited the insulin-induced down-regulation of IRS-1 in 3T3-L1 adipocytes and, also, the C8-PIP3-stimulated degradation of IRS-1 in vitro . These results suggest that PI 3-kinase and its 3-phosphoinositide products mediate the insulin-induced down-regulation of IRS-1 in 3T3-L1 adipocytes. Biochem Pharmacol, 1995 Aug 25, 50(5), 697 - 703 Enzyme kinetic properties of human recombinant arylamine N-acetyltransferase 2 allotypic variants expressed in Escherichia coli; Hickman D et al.; Arylamine N-acetyltransferase (NAT2) catalyses the N-acetylation of primary arylamine and hydrazine drugs and chemicals . N-Acetylation is subject to polymorphism, and humans can be categorized as either fast or slow acetylators according to their ability to N-acetylate certain arylamine substrates in vivo . Genetic variants at the polymorphic NAT2 locus have been described . We expressed five of the most common NAT2 variants (NAT2 4, NAT2 5A, NAT2 5B, NAT2 6A and NAT2 7B) in Escherichia coli as a convenient source of the human variants . The apparent Km values (at 100 microM acetyl CoA as co-substrate) of the different NAT2 variants for sulphamethazine, dapsone, p-anisidine, 2-aminofluorene, procainamide and isoniazid were determined . Data show that the apparent Km of the slow variant NAT2 7B for the arylamine sulphamethazine was 10-fold lower than all the other allotypes . The apparent Km for the structurally related sulphone antibiotic dapsone was 5-fold lower for the slow variant NAT2 7B when compared with the wild-type NAT2 4 . These results indicate that the NAT2 7B specific amino acid substitution, Gly286-Glu, is important in promoting the binding of sulphamethazine and dapsone to the active site. Ann Intern Med, 1995 Aug 15, 123(4), 260 - 8 Alternative management strategies for patients with suspected peptic ulcer disease; Fendrick AM et al.; OBJECTIVE: To estimate the clinical and economic effects of available invasive and noninvasive management strategies for peptic ulcer and Helicobacter pylori in persons with symptoms suggesting peptic ulcer disease . DESIGN: Cost-effectiveness analysis using a decision analytic model . INTERVENTION: 2 immediate endoscopy and 3 noninvasive diagnostic and treatment strategies were evaluated: 1) immediate endoscopy for peptic ulcer and biopsy for H . pylori; 2) immediate endoscopy without biopsy; 3) serologic test for H . pylori; 4) empiric treatment with antisecretory therapy; and 5) empiric treatment with antisecretory therapy and antibiotic agents to eradicate H . pylori . MEASUREMENTS: Cost per ulcer cured and cost per patient treated . RESULTS: The estimated costs per ulcer cured by strategy were as follows: 1) endoscopy and biopsy for H . pylori, $8045; 2) endoscopy without biopsy, $6984; 3) serologic test for H . pylori, $4541; 4) empiric antisecretory therapy, $4835; and 5) empiric antisecretory and antibiotic therapy, $4155 . The predicted costs per patient treated were as follows: 1) endoscopy and biopsy for H . pylori, $1584; 2) endoscopy without biopsy, $1375; 3) serologic test for H . pylori, $894; 4) empiric antisecretory therapy, $952; and 5) empiric antisecretory and antibiotic therapy, $818 . The cost-effectiveness advantage of the noninvasive strategies diminished as the cost of endoscopy decreased or as the probability of recurrent symptoms increased in patients initially managed without endoscopy . CONCLUSION: Endoscopy, although costly, precisely guided diagnosis and treatment and thus potentially reduced the number of patients inappropriately treated . However, the safety and effectiveness of less expensive, less invasive diagnostic and treatment strategies strongly support initial noninvasive care of symptomatic persons thought to have peptic ulcer disease. J Am Vet Med Assoc, 1995 Aug 15, 207(4), 455 - 6 Severe pruritus associated with lymphoma in a dog; Anderson RK et al.; A dog with chronic pruritus that was refractory to antibiotic, corticosteroid, and antihistamine treatment was found to have lymphoma involving the spleen and associated lymph nodes . Pruritus rapidly resolved on removal of the tumor and recurred on reappearance . The association of generalized pruritus with an occult malignant process may be difficult to assess, but after excluding the more common causes of pruritus, a visceral malignancy should be considered. Biochemistry, 1995 Aug 8, 34(31), 9944 - 50 Sequence preference for strand cleavage of gapped duplexes by dynemicin A: possible mechanism of sequence-dependent double-stranded breaks; Kusakabe T et al.; A double-stranded DNA cleavage mechanism by a novel enediyne type antitumor antibiotic, dynemicin A, has been investigated through sequence-dependent strand breakage of a series of duplexes containing a single nucleotide gap . We found that (1) dynemicin A breaks specifically at the 3'-shifted position by one base opposite the gap, (2) the strong cleavage is detected at 5'-Pu_Pu/3'-PyPuPy sequences, and (3) dynemicin H (aromatized form of dynemicin A) gives only a small inhibition effect (20%) on the cleavage of gapped duplex by dynemicin A . The long half-life of aromatization of dynemicin A (118 min, in the presence of DNA) obtained from HPLC analysis provides enough time for the second cleavage . The present results strongly indicate a two-step mechanism for the double-stranded DNA scission of dynemicin A . Namely, this double-stranded break is caused by two drug molecules, each of which cuts one DNA strand. Med J Aust, 1995 Aug 7, 163(3), 137 - 40 Prospective study of diarrhoeal outbreaks in child long-daycare centres in western Sydney; Ferguson JK et al.; OBJECTIVE: To investigate outbreaks of diarrhoeal illness in children attending long-daycare centres (LDCs), to characterise parasitic, bacterial and viral isolates from the children's faeces and to identify individual and LDC risk factors for diarrhoea . DESIGN: Eleven-month prospective case-control study of diarrhoeal outbreaks among children in LDCs . SUBJECTS: 2368 children attending 35 LDCs in the western Sydney area . MAIN OUTCOME MEASURES: Frequency of diarrhoeal outbreaks, rate of attack and spread to family members; pathogens isolated from stools; and individual and LDC risk factors . RESULTS: The overall incidence of diarrhoeal disease was low (0.28 outbreaks per centre per year and 0.056 outbreak-associated cases per child-year) . Attack rates during outbreaks varied widely (4%-55%; mean, 15%), as did secondary spread rates to family members (1%-15%; mean, 9%) . Pathogens were isolated from 7% of symptomatic children and 7% of controls; no outbreak was shown to be caused by a recognised pathogen . Children with outbreak-associated diarrhoeal illness were more likely to have suffered vomiting, poor appetite, lack of energy, fever and to have taken antibiotics in the previous week than other children . Hygiene practices varied widely among centres . CONCLUSIONS: We found low incidence and morbidity from diarrhoeal illness in Australian urban LDCs . Diarrhoea in children in LDCs may be caused predominantly by non-infectious factors such as diet and antibiotic exposure . Current hygiene measures in LDCs seem adequate to prevent and contain outbreaks of infectious diarrhoea. Biochem Biophys Res Commun, 1995 Aug 4, 213(1), 130 - 7 Stable production of mutant mice from double gene converted ES cells with puromycin and neomycin; Watanabe S et al.; The antibiotic puromycin is an effective inhibitor of protein synthesis and puromycin N-acetyl transferase gene could be used as a dominant selection marker . We report the effective production of mutant mice from double gene-converted ES cells by selection with G418 and puromycin . We confirmed that (i) puromycin efficiently inhibited the growth of ES cells at a low-dose (0.1 microgram/ml) and for a short time (2 days), independent of G418 selection; (ii) when these selected ES cells were injected into eight-cell stage embryos, the cells produced chimeras with high levels of chimerism; (iii) these chimeric males were fertile and exclusively yielded ES cell-derived offspring; and (iv) each offspring contained both neomycin transferase and puromycin N-acetyl transferase genes. Antibiot Khimioter, 1995 Aug, 40(8), 3 - 6 {Activity of threonine deaminase and biosynthesis of avermectins in the culture of Streptomyces avermitilis}; Mironov VA et al.; The influence of ammonium, threonine, isoleucine and valine on the activity of threonine deaminase and the biosynthesis of avermectins in the culture of two mutants of Streptomyces avermitilis, i.e . a sensitive one and a resistant one with respect to alpha-amino-beta-oxyvaleric acid, a threonine antimetabolite, was studied . It was shown that the synthesis of threonine deaminase was induced by threonine and valine in the mycelium of both the mutants . The level of threonine deaminase was higher in the mycelium of the antimetabolite resistant mutant . The antibiotic activity of the resistant mutant was lower while the relative content of the group B avermectins in the pool of the synthesized avermectins was higher than that in the culture of the sensitive mutant. Immunopharmacol Immunotoxicol, 1995 Aug, 17(3), 451 - 69 Bleomycin and FK 565 enhance the release of GM-CSF from LPS-stimulated BALB/c peritoneal macrophages; Blaney BA et al.; The anti-tumour antibiotic Bleomycin, the experimental immunostimulatory tripeptide FK 565, and the immunosuppressive agent Cyclosporin A were examined for their in vitro effects on the release of the haemopoietic cytokine Granulocyte Macrophage Colony-Stimulating Factor (GM-CSF) from LPS stimulated BALB/c adherent peritoneal macrophages . FK 565 and Bleomycin produced an increase in GM-CSF release indicating that these agents are capable of stimulating peritoneal macrophage populations . Cyclosporin A was found to have no effect. J Pharm Biomed Anal, 1995 Aug, 13(9), 1153 - 9 Study of the stability of tylosin A in aqueous solutions; Paesen J et al.; The decomposition of the 16-membered ring macrolide antibiotic tylosin A in aqueous buffers has been investigated in the pH range 2-13, by means of a liquid chromatographic assay with ultraviolet detection at 280 nm . In acidic medium, tylosin A is converted into tylosin B, while in neutral and alkaline medium, tylosin A aldol is formed together with a number of polar decomposition products of unknown identity . The decomposition kinetics have been studied as a function of the type and concentration of the buffer, ionic strength, pH and temperature. Clin Infect Dis, 1995 Aug, 21(2), 361 - 9 Invasive fungal disease in adults undergoing remission-induction therapy for acute myeloid leukemia: the pathogenetic role of the antileukemic regimen; Bow EJ et al.; Using multivariate techniques, we studied the relationships of cytotoxic regimen, intestinal mucosal damage, and fungal colonization in the pathogenesis of invasive fungal disease in 138 patients undergoing induction therapy for untreated acute myeloid leukemia (AML) according to three institutional protocols: AML-84 (cytarabine/daunorubicin), AML-87 (high-dose cytarabine/etoposide/daunorubicin), and AML-88 (mitoxantrone/etoposide) . Invasive fungal disease occurred in 36%, 6%, and 2.6% of patients participating in protocols AML-87, AML-84, and AML-88, respectively (chi 2 = 23.465; P < .0001) . Protocol AML-87 was the strongest independent predictor in the multivariate model (RR = 26.7; P < .0001) . Cytotoxic therapy-related epithelial damage in the gut, as measured by D-xylose malabsorption, correlated with invasive fungal disease and protocol AML-87 . Fungal colonization, a predictor of invasive fungal disease, correlated with frequent modifications of antibiotic regimens . These results demonstrate the role of cytotoxic regimen-related gut epithelial damage, antibiotic-prescribing behavior, and fungal colonization in the pathogenesis of invasive fungal disease in patients with leukemia. Int J Clin Pharmacol Ther, 1995 Aug, 33(8), 462 - 4 Influence of ethanol ingestion on tetracycline kinetics; Seitz C et al.; The effect of ethyl alcohol ingestion on tetracycline kinetics was studied in 9 healthy male volunteers . They received, on two separate occasions, 500 mg of tetracycline tablets given with water or with an alcoholic beverage . The antibiotic was assayed in plasma, using a HPLC method . Absorption and disposition parameters were calculated according to classical pharmacokinetic techniques for one compartment model . The significance of changes in pharmacokinetic parameters was determined by a multiway ANOVA test . In the present study, ingestion of alcohol caused significant increase of Cmax (from 9.317 to 12.362 micrograms/ml), and increase of AUC (from 62.65 to 94.28 micrograms/ml*h). J Spinal Disord, 1995 Aug, 8(4), 278 - 83 Treatment of postoperative wound infections following spinal fusion with instrumentation; Abbey DM et al.; Postoperative wound infections following spinal fusion with instrumentation often present diagnostic and therapeutic difficulties . This article reviews 34 such infections . An infection rate of 3.7% was noted . Depending on various clinical indicators, treatment strategies included short-course antibiotics, prolonged intravenous antibiotics, or intravenous antibiotics followed by suppressive antibiotics and eventual hardware removal . To eradicate these infections, removal of instrumentation is often required; this option, however, may result in an unstable spine . Treatment algorithms were developed for treatment of postoperative spinal surgical site infections and to minimize the possibility of spine instability . All patients were cured of their infections. Compr Ther, 1995 Aug, 21(8), 438 - 44 The acute respiratory distress syndrome: current trends in pathogenesis and management; Levy PC et al.; Management of patients in ARD remains a complex diagnostic and difficult therapeutic problem . Although the authors have focused on several new and exciting management strategies, it is important to recognize that the vast majority of patients with ARDS simply require meticulous general medical care . In this era of invasive monitoring and other care . In this era of invasive monitoring and other complex technologies, there is sometimes a tendency to neglect the basic issues such as judicious use of antibiotics to avoid superinfection with resistant organisms or antibiotic-associated diarrhea; removal of unnecessary intravenous lines to minimize line related infections; and maintenance of adequate nutrition to promote good skin and mucosal integrity as well as preserving important muscle mass all too often receive a low priority . It is anticipated that with meticulous general medical care, as well as selective implementation of the above treatment strategies, improvement in the outcome of patients is an achievable goal. Protein Expr Purif, 1995 Aug, 6(4), 401 - 7 A bifunctional vector suitable for both site-directed mutagenesis and recombinant expression of interferon-tau in Escherichia coli; Li J et al.; In order to produce workable quantities of a large number of mutant forms of recombinant ovine and bovine interferon-t (IFN-t), a bifunctional vector, pME-2, was developed, which combines a mutant selection system and a strong promoter providing controlled expression . An EcoRI/KpnI fragment containing the complete Trp promoter, a Shine-Dalgarno sequence, and an AT-rich region from the pTrp-2 expression vector was inserted into the large fragment of EcoRI/KpnI-digested pALTER-1 plasmid, which had been modified by eliminating a ClaI site . The pALTER-1 phagemid provides a highly efficient, antibiotic-dependent system for selection of mutant plaques . The existing T7 promoter was then eliminated from the recombinant phagemid to create the pME-2 vector . Ovine and bovine IFN-t genes lacking the coding region for the signal peptide, but with an ATG codon ahead of the open reading frame, were inserted into the multicloning site of pME-2 . Following site-directed mutagenesis designed to produce elongations, truncations, and single and multiple amino acid replacements in the protein products, mutant genes were selected in Escherichia coli BMH 71-18 and efficiently expressed in E . coli JM-101 in response to the inducer of the Trp promoter indole acetic acid . The recombinant IFN were solubilized from washed inclusion bodies in guanidinium-HCl and 2-mercaptoethanol and allowed to refold in aerated buffer . The procedure provides high yields of fully active, homogeneous IFN-t and can be accomplished within 1 week. FEMS Microbiol Lett, 1995 Aug 1, 130(2-3), 231 - 6 Protective effect of Brucella outer membrane complex-bearing liposomes against experimental murine brucellosis; Vitas AI et al.; Liposomes of stable multilamellar type, which previously demonstrated great efficiency in antibiotic transport, were used in this study as transport vehicles of antigenic extracts of Brucella melitensis (HS: complex of lipopolysaccharide/phospholipids/outer membrane proteins) . The incorporation of HS into positively charged liposomes produced a protective effect against experimental murine brucellosis when they were administered 1 day before or 2 days after infection, as the number of colony-forming units in the spleen was reduced in relation to the untreated control group (P < 0.01) . On the other hand, the use of HS-free or bound in liposomes with negative net charge did not produce a significant effect . Moreover, the incorporation of HS into cationic liposomes eliminated the toxicity of the lipopolysaccharide. DNA Cell Biol, 1995 Aug, 14(8), 709 - 17 Reporter gene expression upon stable transfection when only a TATA box or a TATA box plus Sp1 sites are present 5' to the gene; Warshamana GS et al.; Episomal plasmids for stable transfection of mammalian cell cultures were constructed that have a G418-resistance (neo) gene immediately downstream of a highly truncated promoter . These plasmids had a function hygromycin-resistance gene (hyg) as a selectable marker . Surprisingly, in LTK- cells, but not HeLa cells, stably transfected with these BK virus-based plasmids having no promoter elements adjacent to the neo gene, readthrough transcription, probably from about 1 kb upstream, gave almost as efficient expression of the neo gene as of the hyg gene with a full-length promoter immediately upstream . When the transfecting plasmids contained Epstein-Barr virus (EBV) DNA sequences for episomal maintenance and had multiple Sp1 sites and a TATA box as the only promoter elements 5' to the neo gene, only about 3-9% of HeLa transfectants were G418 resistant (G418R) . In transfections with analogous plasmids lacking these promoter elements 5' to the neo gene, no G418R colonies were seen . The establishment of the G418R phenotype probably required integration of plasmid DNA into favorable chromosomal sites and was aided by the presence of the TATA box plus Sp1 sites as a subminimal promoter . The absence of detectable G418-resistance in most of the HeLa transfectant clones obtained with EBV-type plasmids, even at a high plasmid copy number and even when a TATA box and six Sp1 sites were present immediately upstream of the neo gene, indicates that these elements do not suffice for appreciable gene expression in vivo and that this is a suitable model system for studying DNA rearrangements that can potentiate expression of the neo gene. Ann Thorac Surg, 1995 Aug, 60(2 Suppl), S160 - 4 Biaxial mechanical properties of explanted aortic allograft leaflets; Christie GW et al.; The leaflets of 33 aortic allograft valves inserted using the freehand method were retrieved at reoperation, and the mechanical properties of the tissue were measured using biaxial testing methodology . Before insertion, the valves had been sterilized for 24 hours in either PSKA or CLPVA antibiotic solutions and then were either wet stored or cryopreserved . The cryopreserved valves were sterilized with CLPVA only, so there were three different treatment types in all . The controls were a set of unimplanted cryopreserved aortic valves . The radial stretch of the valve leaflets was measured and was analyzed as a function of the age of the donor in the case of the controls and the age of the donor plus the duration of implantation for the explanted valves . The biaxial tension test was used to determine the maximum radial stretch of each leaflet because this variable dictates the area of coaptation and, ultimately, valve competency . It was found that the radial stretch of the allograft leaflets after implantation declined faster with time than did the stretch of the native aortic valve leaflet controls . This greater rate of stretch reduction depended mostly on the degree of similarity between the stretch of the donor leaflets and that of the recipient at the time of implantation . No conclusion could be reached about the influence of the preimplantation storage method because of the different time intervals of implantation applicable to each case . After matching for annulus size, matching the ages of donor and recipient is a good graft-selection strategy, but it may be better to use a slightly older donor.(ABSTRACT TRUNCATED AT 250 WORDS) Ann Thorac Surg, 1995 Aug, 60(2 Suppl), S146 - 50 Short-course cyclosporin A therapy for definite allograft valve survival immunosuppression in allograft valve operations; Yankah AC et al.; This study was designed to determine the effect of short-course cyclosporin A therapy (10 mg/kg daily for 14 days) on allograft valve survival across the histocompatibility barriers in the following rat models; (1) syngeneic Lewis to Lewis (herein referred to as autografts), (2) weakly allogeneic AS to Lewis (RT1 compatible, non-RT1-incompatible), and (3) strongly allogeneic CAP to Lewis (RT1 and non-RT1-incompatible) . Cyclosporin A-treated and untreated recipient animals (Lewis) received allovital and antibiotic-treated viable allografts implanted into the infrarenal aorta . Second-set skin grafting was performed 3 weeks after heterotopic valve implantation to test for immunogenicity and presensitization . The animals (Lewis) were sacrificed serially on days 20, 50, 100, and 150 for immunofluorescence study using mouse monoclonal antibodies (OX6) directed at class II endothelial surface antigens . The allografts in weakly allogenic strains showed no humoral response under a short course of cyclosporin A . The cyclosporin A-untreated allovital grafts and the viable (antibiotic-treated) valves demonstrated fibrocalcification on the 100th and 150th postoperative days, respectively . In conclusion, it seems that a short course of nontoxic immunosuppression could arrest allograft rejection and thus prevent early degeneration of allografts . Furthermore, antibiotic-treated viable allografts seemed to be more durable than allovital grafts. Ann Thorac Surg, 1995 Aug, 60(2 Suppl), S127 - 30 Humoral immune response to human aortic valve homografts; Smith JD et al.; The humoral response to homograft valves in humans is largely unknown . The anti-human lymphocyte antigen (HLA) antibody production, specificity, and immunoglobulin class were examined sequentially in 73 patients undergoing aortic valve replacement . In addition, the long-term production of antibodies was examined in a cross-sectional study of 160 patients at periods varying from 1 to 15 years postoperatively . Human lymphocyte antigen antibodies were produced in 17 of 30 antibiotic-sterilized homografts (56%) and in 15 of 15 "homovital" homograft recipients, compared with 6 of the 28 control xenograft recipients (21%) (p < 0.001) . The HLA antibodies were immunoglobulin G in all 15 homovital homografts, in 11 of 17 antibiotic-sterilized homografts, and in four of the six xenograft cases . Human lymphocyte antigen specificities could be assigned to the antibodies in 21 cases . In 10 of 11 cases in which donor HLA typing data were available, the antibodies detected were directed against donor HLA class I antigens . Of six possible determinants of HLA antibody production, the type of homograft valve implanted (homovital or antibiotic sterilized) correlated with antibody formation . In the cross-sectional study, 66 of the 85 homovital homograft recipients tested for HLA antibodies after 1 year were found to have antibodies, compared with 29 of 75 antibiotic-sterilized homograft recipients (p = 0.00003) . We conclude that homografts appear to stimulate a strong donor HLA-specific antibody response, particularly of the immunoglobulin G class . This is most common in homovital valve recipients . These antibodies can persist for 15 years after operation . The clinical significance of this response requires further investigation. Ann Thorac Surg, 1995 Aug, 60(2 Suppl), S101 - 4 Allograft implantation in pediatric cardiac surgery: surgical experience from 1982 to 1994; Weipert J et al.; Between July 1982 and April 1994, a total of 290 patients (median age 6.5 years, range 1 month to 32.1 years, 69 patients younger than 1 year) underwent repair of their cardiac malformation by insertion of an allograft . The diagnoses were truncus arteriosus communis (n = 78, 27.0%), tetralogy of Fallot (n = 59, 20.0%), pulmonary atresia (n = 72, 25.0%), double outlet right ventricle (n = 15, 5.0%), complex transposition of the great arteries plus pulmonary stenosis (n = 37, 13.0%), and others (n = 29, 10.0%) . Either pulmonary (n = 69) or aortic (n = 221) cadaver allografts were implanted . Two hundred twenty-nine of the allografts were antibiotic preserved . Since January 1991 (n = 61), a new cryopreservation procedure was employed for standardized uniform cooling using heat sinks and defined package geometry . Follow-up was complete for 95.2% (n = 276, 1,320 patient-years) . Thirty-day mortality was 9.0% (n = 26) and late mortality was 12.1% (n = 35) . Kaplan-Meier analysis revealed that patient survival was determined mainly by their underlying cardiac disease . All allografts with valve sizes less than 15.0 mm had to be exchanged within 7 years as these patients had outgrown their conduits . When the allograft was larger than 15.0 mm, exchange was necessary in 20% at 10 years . ABO compatibility and aortic or pulmonary origin of the allograft were not significant influences on allograft survival.(ABSTRACT TRUNCATED AT 250 WORDS) Surg Clin North Am, 1995 Aug, 75(4), 783 - 97 Management of infected aortic grafts; Lawrence PF; Aortic graft infection will continue to occur in a small proportion of patients who undergo reconstructive aortic surgery . For most patients, the standard approach should use extra-anatomic bypass, followed by complete excision of the graft, as the treatment of choice . However, in selected patients who have localized infection, are high risk surgical candidates, or have grafts located in positions that preclude removal, less aggressive alternatives such as topical antibiotic irrigation, graft resection with debridement and replacement, and in situ replacement with a biologic graft take an increasing role . When prosthetic grafts are developed that are less susceptible to reinfection, owing to incorporation of antibiotics into the graft, in situ replacement may become the treatment of choice . In spite of many advances in the management of aortic graft infection, this complication continues to carry a high mortality and amputation rate, and consequently should be managed by surgeons who have a particular interest and experience in managing this particular problem . With a thorough understanding of the circumstances of the original operation, bacteria infecting the graft, extent of graft infection, and management alternatives, most patients can survive prosthetic aortic graft infections with a combined morbidity and mortality of less than 50%. Am Fam Physician, 1995 Aug, 52(2), 559 - 68 Current surgical treatment of valvular heart disease; Katz NM; Surgery for valvular heart disease has undergone important refinements during the past several years . The general indications for valvular surgery are the presence of symptoms that interfere with the patient's lifestyle and that cannot be controlled with medical therapy, and indications of a threat to continued survival, such as angina, dyspnea, effort syncope or progressive impairment of ventricular contractility . Infective endocarditis may also be an indication for valvular surgery in patients with congestive heart failure, recurrent embolism, persistent infection despite antibiotic therapy, large vegetations or progressive conduction defects . Surgical procedures for the treatment of valvular heart disease include reconstruction techniques and valve replacement procedures . Reconstructive surgery minimizes the amount of materials that must be implanted . Advances in myocardial preservation have reduced the risk of such complex cardiac surgical procedures as multiple valve replacements and valve replacements combined with coronary artery bypass surgery . Follow-up care is important to monitor valve function, fluid balance and anticoagulation. Infect Immun, 1995 Aug, 63(8), 2924 - 30 Construction and use of integration plasmids to generate site-specific mutations in the Actinomyces viscosus T14V chromosome; Yeung MK; Stable transformants of Actinomyces viscosus T14V carrying heterologous DNA were obtained with the aid of integration plasmids . These plasmids contained a kanamycin resistance (Kmr) gene flanked by A . viscosus T14V genomic DNA, including parts of the type 1 structural fimbrial subunit gene (fimP) on one or both sides of the antibiotic marker . Significantly more Kmr transformants were obtained with a plasmid carrying longer segments of homologous strain T14V DNA . Integration of this plasmid into the A . viscosus T14V genome affected the expression and function of type 1 fimbriae in the transformants . In the transformant strain designated A . viscosus MY50D, the inactivated fimP replaced the wild-type fimP via allelic replacement . A . viscosus MY51S and MY52S each contained a copy of the plasmid integrated into the genome by a Campbell-like insertion mechanism . A . viscosus MY50D and MY51S lacked type 1 fimbriae and did not bind to proline-rich proteins (the fimbrial receptors) immobilized on nitrocellulose . In contrast, strain MY52S synthesized the structural subunit protein, as detected by immunostaining with anti-A . viscosus T14V type 1 fimbria antibodies . However, the high-molecular-weight proteins observed in sodium dodecyl sulfate-polyacrylamide gels of fimbriae from the cell wall of the wild-type strain T14V were absent in cell wall preparations of this strain . Moreover, A . viscosus MY52S failed to bind, in vitro, to proline-rich proteins . Thus, these results demonstrate that insertion of heterologous DNA at specific sites of the Actinomyces genome can be facilitated with integratable plasmids and that the transformants and mutants generated will aid in the delineation of the roles and contributions of specific genes to the structure and function of any macromolecule produced by these organisms. J Neurosurg, 1995 Aug, 83(2), 243 - 7 Spinal tuberculosis: a diagnostic and management challenge; Nussbaum ES et al.; The authors reviewed 29 cases of spinal tuberculosis treated from 1973 to 1993 with an average follow-up time of 7.4 years . Clinical findings included back pain, paraparesis, kyphosis, fever, sensory disturbance, and bowel and bladder dysfunction . Twenty-two patients (76%) presented with neurological deficit; 12 (41%) were initially misdiagnosed . Sixteen patients (55%) had predominant vertebral body involvement; nine had marked bone collapse with neurological compromise . Eleven individuals (39%) had intraspinal granulomatous tissue causing neurological dysfunction in the absence of bone destruction, and two (7%) had intramedullary tuberculomas . All patients received antituberculous medications: 13 were initially treated with bracing alone, eight underwent laminectomy and debridement of extra- or intradural granulomatous tissue, and eight underwent anterior, posterior, or combined fusion procedures . No patient with neurological deficit recovered or stabilized with nonoperative management . Thirteen patients were readmitted with progression of inadequately treated osteomyelitis; 12 (92%) of these required new or more radical fusion procedures . Anterior fusion failure was associated with marked preoperative kyphosis and multilevel disease requiring a graft that spanned more than two disc spaces . Courses of antibiotic medications shorter than 6 months were invariably associated with disease recurrence . It was concluded that 1) patients should receive at least 12 months of appropriate antituberculous therapy; 2) individuals with neurological deficit should undergo surgical decompression; 3) laminectomy and debridement are adequate for intraspinal granulomatous tissue in the absence of significant bone destruction; 4) when vertebral body involvement has produced wedging and kyphosis, aggressive debridement and fusion are indicated to prevent delayed instability and progression of disease. Kansenshogaku Zasshi, 1995 Aug, 69(8), 934 - 9 {Spontaneous cure of pneumonia caused by Chlamydia pneumoniae}; Miyashita N et al.; A 62-year-old male was admitted to our hospital after an abnormal shadow was pointed out by Chest X-ray in June, 1994, even though he was asymptomatic otherwise (first episode) . The serum IgG antibody against Chlamydia pneumoniae was elevated up to 512-fold in the acute phase and decreased to 32-fold in the convalescent phase using the micro-immunofluorescence (MIF) test, indicating a C . pneumoniae acute infection . In fact, no other micro-organisms were detected . The patient recovered from the pneumonia without any treatment . He was admitted to our hospital again after having right chest pain in December, 1994 (second episode) . An X-ray examination revealed a slight infiltration of the right lower lung field and pleural effusion . In this episode, he received therapy with carbapenem anti-bacterial agent and he recovered from the pneumonia 9 days after the administration of the antibiotic . The serum IgG titer against C . pneumoniae was elevated up to 1024-fold on admission, indicating mixed infection with bacteria and C . pneumoniae . It was concluded that both of these episodes indicated a spontaneous cure of the pneumonia which had developed from C . pneumoniae. Rev Esp Enferm Dig, 1995 Aug, 87(8), 590 - 2 {Hepatic actinomycosis: radiologic findings and percutaneous drainage}; Sandoval Polo E et al.; We report a case of hepatic actinomycosis in a woman with previous duodenal ulcer . The findings of ultrasound, computed tomography and abscess imaging are presented . The diagnosis was made by thin needle aspiration biopsy under computed tomography guidance . The treatment consisted in percutaneous drainage and intravenous antibiotic therapy. Aust Dent J, 1995 Aug, 40(4), 267 - 70 Australian Dental Research Fund Trebitsch Scholarship . Efficacy of antifungal prophylaxis in bone marrow transplantation; Quirk PC et al.; Oral candidal infection is a common problem in bone marrow transplantation . This prospective study compared the effectiveness of antifungal prophylaxis with topical antifungals (nystatin and amphotericin B suspensions) versus oral fluconazole in 196 patients undergoing bone marrow transplantation . Oral candidosis occurred frequently in the group receiving topical antifungals (61/113, 54%), but was rare in the group receiving fluconazole (6/83, 7%) . The difference in efficacy between the two groups was highly significant (p < 0.00001) . There was no difference in the incidence of suspected systemic fungal infection between the two groups . While nausea was a problem with antifungal suspensions, no significant adverse reactions to fluconazole occurred . Because of greater efficacy in preventing oral candidosis and better patient tolerance, oral fluconazole is preferred to antifungal suspensions for prophylactic use in patients undergoing bone marrow transplantation. Qual Life Res, 1995 Aug, 4(4), 309 - 18 Evaluating the quality of life associated with rifabutin prophylaxis for Mycobacterium avium complex in persons with AIDS: combining Q-TWiST and multiattribute utility techniques; Revicki DA et al.; Our objective was to evaluate the effect of rifabutin prophylaxis in patients with AIDS and CD4 counts of less than 200 per cubic millimetre using a combination of Q-TWiST (quality-adjusted time without symptoms and toxicity) and multiattribute health utility assessment . The design consisted of a secondary analysis of two previously reported multicentre, randomized, placebo-controlled clinical trials conducted in 78 academic, community and Department of Veterans Affairs HIV centres and private practices . 542 patients with AIDS and CD4 counts of less than 200 per cubic millimetre were assigned to rifabutin 300 mg/day and 562 were assigned to a placebo . A modified Q-TWiST approach was used for comparing treatments based on the occurrence and duration of time with and without severe symptoms and clinical endpoints . Health states were constructed to represent combinations of clinical events experienced by study patients . Five physicians assigned utilities for health states using a six-attribute health classification system . These utilities were used to adjust survival for QOL . The rifabutin and placebo groups were compared using estimated quality-of-life-adjusted days . The incidence of MAC was 9% for the rifabutin group and 18% for the placebo group (p < 0.001) . Differences, although not statistically significant, were observed for rates of survival and hospitalization . The rifabutin group experienced less anaemia (p < 0.02), and fever and night sweats (p < 0.02) than the placebo group . Average Q-TWiST days were 325 for the rifabutin group and 309 for the placebo group (p < 0.05) . Q-TWiST days were significantly lower for patients with MAC bacteraemia (p < 0.04) and hospitalizations (p < (0.003) . Rifabutin prophylaxis resulted in fewer MAC infections and greater quality-of-life-adjusted days of survival compared to no rifabutin . Quality-of-life-adjusted survival, based on a combination of the Q-TWiST and multiattribute health utility index, is a feasible approach for evaluating the outcomes of medical treatment . Future studies should, however, use patient-assigned utility weights to compute Q-TWiST scores, since physician generated utilities may differ significantly from those of patients. Pharm Res, 1995 Aug, 12(8), 1205 - 10 The effect of electrostatic charge interactions on release rates of gentamicin from collagen matrices; Singh MP et al.; PURPOSE . This work studied the effect of changes in the magnitude of electrostatic charge interactions on the release kinetics of gentamicin from collagen matrices . METHODS . The charge distribution on collagen was altered by specific charge chemistries to yield net negative charges which exhibited binding interactions with positively charged gentamicin . The adsorption isotherms were measured to characterize binding interactions and release of gentamicin from modified matrices were measured . The release rates were compared to a mathematical model based on an instantaneous desorption coupled with diffusion mechanism . RESULTS . Ninety percent of the gentamicin loaded was released from native collagen matrices in 2.5 days (one-sided slab geometry in-vitro) . Succinylated collagen matrices released 70% in 2.5 days and phosphonylated collagen matrices released 50% in 2.5 days . Excellent agreement between model predictions and experiment results were obtained . CONCLUSIONS . Modified collagen can be much more effective in antibiotic therapy in sustaining release rates compared to native collagen for charged antibiotics like gentamicin. Acta Paediatr, 1995 Aug, 84(8), 873 - 8 Prognostic factors in childhood bacterial meningitis; Kaaresen PI et al.; The purpose of this study was to identify possible risk factors associated with a poor prognosis in childhood bacterial meningitis . We also analysed the influence of duration of symptoms and prehospital antibiotic therapy on outcome . Ninety-two children aged 1 month to 13.8 years were included, of whom 4 died (4.3%) and 14 (15.2%) experienced permanent neurological sequelae . Hearing impairment was the most frequent sequela and was strongly associated with the length of history . Multiple logistic regression revealed duration of symptoms > 48 h, pre-hospital seizures, peripheral vasoconstriction, < 1000 x 10(6)/l leucocytes in cerebrospinal fluid and temperature < or = 38.0 degrees C on admission as risk factors independently associated with later death or sequelae . There was no association between pre-hospital oral or parenteral antibiotic therapy and outcome . These risk factors may be of value in selecting patients for more intensive therapy and in identifying possible candidates for new treatment strategies. Ann Plast Surg, 1995 Aug, 35(2), 204 - 7 Atypical Mycobacterium and breast surgery; Widgerow AD et al.; An unusual case of atypical mycobacterium infection following breast ptosis correction is described . This was successfully treated with a combination antibiotic regime . Breast surgery and atypical mycobacterium is discussed with reference to diagnosis management and suggested treatment regimes. Z Gastroenterol, 1995 Aug, 33(8), 449 - 53 {Therapy refractory atypical polyarthritis and cryoglobulinemia in a patient with colon carcinoma and palliative intestinal bypass . Differential diagnosis: carcinoma-polyarthritis or bypass arthritis}; Kanzler S et al.; The case of a 63 year old woman with mesenteric recurrence of a colonic carcinoma and infiltration of the duodenum is reported . To bypass duodenal stenosis a duodenojejunostomy was performed . Three months later the patient developed severe atypical polyarthritis which led to hospitalization . The arthritis affected large and small joints in an asymmetrical pattern . Fever and Raynaud's phenomenon of both hands accompanied the arthritis . Elevated sedimentation rate, acute phase proteins, cryoglobulinemia and immune complexes were remarkable laboratory findings . Rheumatoid factor was absent . In the subsequent course the polyarthritis was refractory to steroids and nonsteroidal anti-inflammatory drugs . Only treatment with broad-spectrum antibiotics ameliorated the arthritis . Postenteric reactive arthritis, septic arthritis and metastatic arthritis could be excluded . Although the patient had a family history of rheumatoid arthritis and a HLA-type DR4 the diagnosis of rheumatoid arthritis was not very likely since distal interphalangeal joints were affected, rheumatoid factor was absent and antibiotic therapy was successful . The case serves to discuss carcinoma-polyarthritis and bypass-arthritis as the main differential diagnosis. Ryumachi, 1995 Aug, 35(4), 693 - 8 {An autopsy case of segmental mediolytic arteritis (SMA) accompanied with microscopic polyarteritis nodosa}; Ito MR et al.; Segmental Mediolytic Arteritis (SMA) is a very rare arterial lesion which is limited in adults to the involvement of the intra-abdominal muscular arteries . The pathology is characterized by segmental disruption of the arterial media which leads segmental mediolysis, with subsequent dissecting aneurysm or rupture . A 73-year-old man was admitted to a hospital because of high fever, general fatigue and weight loss . These symptoms were resistant to antibiotic therapy, and soon after, renal insufficiency developed . Three months after the onset of symptoms, he died suddenly of hemorrhagic shock . Autopsy revealed rupture of the splenic artery and systemic necrotizing arteritis in the small-sized arteries of liver, pancreas and kidneys, as well as in the connective tissues around the adrenal glands . Histopathology of the splenic artery was consistent with SMA, and that of the systemic vascular lesions, with microscopic polyarteritis nodosa . Focal glomerular lesions characteristic of crescentic and/or granulomatous glomerulonephritis were present . A developmental mechanism for SMA is discussed with respect to this case together with a review of previous reports of this disease. Orthopade, 1995 Aug, 24(4), 353 - 9 {Salvage surgery in chronic infection following total hip prosthesis}; Ochsner PE et al.; Thirteen patients were analyzed who suffered from chronic infection after total hip replacement . Some of them had had severe soft tissue defects or multiple fistulae for years . Some showed acute, sometimes life-threatening infection after long-standing loosening of the prosthesis . Therapy consisted of radical debridement, installation of a closed suction-irrigation drainage system and if another total hip prosthesis was implanted of a specific antibiotic management, including rifampin . In one case treatment was limited to the achievement of a permanent fistula . The average follow-up time was 4.3 years . With or without total hip reimplantation infections were healed as a rule and the decrease in pain was marked . There was only a partial increase in walking ability . In these severely damaged patients treatment can result in marked amelioration of the quality of life but only exceptionally in normalization. Orthopade, 1995 Aug, 24(4), 319 - 25 {Local antisepsis in infected total hip endoprosthesis}; Wagner M; Between 1991 and 1993, 34 infected total hip prostheses were treated with the topical antiseptic hexamethylenbiguanide (Lavasept) in addition to thorough debridement of infected and necrotic tissue and systemic antibiotic administration . In 4 cases (group 1) a contaminated hematoma was treated within the first 3 weeks after joint replacement . Soft tissue revision without removal of the prosthesis was performed in 6 cases (group 2) . In 18 cases (group 3) a one-stage exchange of the infected prosthesis was done . In 6 cases (group 4), local and general conditions were so poor that the prosthesis was removed without replacement . The success rate was 100% in group 1, 20% in group 2, and 77% in group 3 . In group 4, 1 patient died of respiratory problems 12 days after surgery while in 2 patients the infection healed uneventfully and in 1 patient healing was achieved after a second revision . An 81-year-old patient in poor general condition had an impressive improvement of his severe infection, although very minor drainage continued . Hexamethylenbiguanide has proven to be a useful supplement to thorough surgical revision . However, longer follow-up data are required. Orthopade, 1995 Aug, 24(4), 314 - 8 {Infected hip joint prosthesis . Viewpoints for 1-stage and 2-stage prosthesis exchange}; Wagner H et al.; When treating an infected hip prosthesis, there are a number of medical, technical and biomechanical considerations . No ideal solution for all problems is available . In individual cases an optimal compromise must be found . The means for curing the infection and the one for maintaining hip stability can counteract each other . Basically, three options are available: removal of the prosthesis without replacement and one- or two-stage replacement . With all three options thorough surgical debridement is vitally important . The introduction of antibiotic cement and cementless titanium implants, together with very effective local antiseptics, has remarkably improved our treatment of this problem . Therefore, removal of infected prostheses without replacement is not as well accepted now as it has been in the past. Biochim Biophys Acta, 1995 Jul 25, 1263(1), 60 - 6 Close similarity among streptavidin-like, biotin-binding proteins from Streptomyces; Bayer EA et al.; Two strains of Streptomyces venezuelae were found to produce high-affinity, biotin-binding proteins, termed streptavidin v1 and v2, respectively . Both proteins were isolated to purity, and their corresponding genes were cloned and sequenced . Compared to streptavidin from S . avidinii, streptavidin v1 had only a single amino acid substitution and streptavidin v2 showed 9 such differences . The substitutions were remarkably conservative, none of which affected the amino acid residues known to be important to the biotin-binding properties or to the structure of the tetrameric protein . The results also indicate that the biosynthesis of such biotin-binding proteins is not simply a curious anomaly in a single species of Streptomyces . It is suggested that the classification of S . avidinii as a unique species should be reconsidered . The occurrence of these proteins appears to be linked to the production of an unusual synergistic antibiotic complex. Mol Gen Genet, 1995 Jul 22, 248(1), 33 - 42 In vivo reconstitution of an active siderophore transport system by a binding protein derivative lacking a signal sequence; Rohrback MR et al.; Transport of iron (III) hydroxamates across the inner membrane of Escherichia coli depends on a binding protein-dependent transport system composed of the FhuB, C and D proteins . The FhuD protein, which is synthesized as a precursor and exported through the cytoplasmic membrane, represents the periplasmic binding protein of the system, accepting as substrates a number of hydroxamate siderophores and the antibiotic albomycin . A FhuD derivative, carrying an N-terminal His-tag sequence instead of its signal sequence and therefore not exported through the inner membrane, was purified from the cytoplasm . Functional activity, comparable to that of wild-type FhuD, was demonstrated for this His-tag-FhuD in vitro by protease protection experiments in the presence of different substrates, and in vivo by reconstitution of iron transport in a fhuD mutant strain . The experimental data demonstrate that the primary sequence of the portion corresponding to the mature FhuD contains all the information required for proper folding of the polypeptide chain into a functional solute-binding protein . Moreover, purification of modified periplasmic proteins from the cytosol may be a useful approach for recovery of many polypeptides which are normally exported across the inner membrane and can cause toxicity problems when overproduced. J Biol Chem, 1995 Jul 21, 270(29), 17339 - 43 Identification of a flavin:NADH oxidoreductase involved in the biosynthesis of actinorhodin . Purification and characterization of the recombinant enzyme; Kendrew SG et al.; The biosynthesis of the polyketide antibiotic actinorhodin by Streptomyces coelicolor involves the oxidative dimerization and hydroxylation of a precursor, most likely dihydrokalafungin, as the final steps in its formation . Mutations in the actVB gene block these last steps, and the mutants secrete kalafungin as a shunt product . To investigate the role of the actVB gene in these transformation, we have overexpressed the gene in Escherichia coli and purified and characterized the recombinant protein . ActVB was shown to catalyze the reduction of FMN by NADH to give NAD and FMNH2, which, unusually, is released into solution . The protein contains no chromogenic cofactors and exhibits no requirements for added metal ions . The reaction obeys simple kinetics and proceeds through the formation of a ternary complex; Km values for FMN and NADH are 1.5 and 7.3 microM, respectively, and kcat is about 5 s-1 . FAD and riboflavin are also substrates for the enzyme, although they have much higher Km values . The subunit structure of the enzyme was investigated by analytical ultracentrifugation, which showed the protein to exist in rapid equilibrium between monomer and dimer forms . The possible role of this oxidoreductase in the oxidative chemistry of actinorhodin biosynthesis is discussed. Biochemistry, 1995 Jul 18, 34(28), 9177 - 84 Mechanism of protein synthesis inhibition by didemnin B in vitro; SirDeshpande BV et al.; The cytotoxic and immunosuppressive marine depsipeptide didemnin B is a potent inhibitor of protein biosynthesis in intact cells . Here, didemnin B is shown to inhibit protein synthesis in vitro during the elongation cycle, by preventing eukaryotic elongation factor 2-(eEF-2-) dependent translocation . No inhibition of aminoacyl-tRNA delivery or of peptidyltransferase activity is observed . Didemnin B stimulates eEF-1 alpha-dependent aminoacyl-tRNA binding to rabbit reticulocyte ribosomes, and eEF-1 alpha is required for inhibition of the subsequent translocation of phenylalanyl-tRNA(Phe) from the A- to the P-site . These observations suggest that didemnin B prevents translocation by stabilizing aminoacyl-tRNA bound to the ribosomal A-site, similar to the antibiotic kirromycin, and consistent with the known affinity of didemnins for elongation factor eEF-1 alpha {Crews et al . (1994) J . Biol . Chem . 269, 15411} . Unlike kirromycin, didemnin B does not prevent peptide bond formation, so inhibition is observed only at the translocation step . Inhibition of translocation by didemnin B is attenuated by increasing concentrations of eEF-2. J Biol Chem, 1995 Jul 14, 270(28), 16580 - 7 Herbimycin A induces the 20 S proteasome- and ubiquitin-dependent degradation of receptor tyrosine kinases; Sepp-Lorenzino L et al.; Herbimycin A is an ansamycin antibiotic isolated as an agent that reverses morphological transformation induced by v-src . Although herbimycin A is widely used as a tool for inhibiting multiple tyrosine protein kinases and tyrosine kinase-activated signal transduction, its mechanism of action is not well defined and includes a decrease in both tyrosine kinase protein levels and activity (Uehara, Y., Murakami, Y., Sugimoto, Y., and Mizuno, S . (1989) Cancer Res . 49, 780-785) . We now show that herbimycin A induces a profound decrease in the total cellular activity of transmembrane tyrosine kinase receptors, such as insulin-like growth factor, insulin, and epidermal growth factor receptors . A substantial proportion of the in vivo inhibition could be explained by an increase in the rate of degradation . The enhanced degradation of insulin-like growth factor-insulin receptor was prevented by inhibitors of the 20S proteasome, whereas neither lysosomotropic agents nor general serine- and cysteine-protease inhibitors were active in preventing receptor degradation induced by herbimycin A . Moreover, in a temperature-sensitive mutant cell line defective in the E1-catalyzed activation of ubiquitin, herbimycin A treatment at the restrictive temperature did not result in the degradation of insulin receptor . These results suggest that herbimycin A represents a novel class of drug that targets the degradation of tyrosine kinases by the 20S proteasome . The ubiquitin dependence of this process indicates that this degradation of tyrosine kinases might involve the 20S proteasome as the proteolytic core of the ubiquitin-dependent 26S protease. Oncogene, 1995 Jul 6, 11(1), 161 - 73 Suppression of RAS and MOS transformation by radicicol; Zhao JF et al.; Activated versions of ras and mos oncogenes subvert the signal transduction pathway by mimicking transducers at the plasma membrane and cytosol respectively . Radicicol (UCS1006), an antifungal antibiotic, had the ability to suppress transformation by ras and mos oncogenes in a rapid, reversible and dose-dependent manner . UCS1006 inhibited MAP kinase activity (both ERK1 and ERK2) in untransformed as well as ras and mos transformed cells . However, ERK2 but not ERK1 activity was constitutively elevated in ras and mos transformed cells used in this study . In addition, a 62 kDa (kilodalton) phosphoprotein was identified whose tyrosine phosphorylation was inhibited by UCS1006, in both ras and mos transformed cells . This 62 kDa phosphoprotein, which was found to be heavily phosphorylated on tyrosine residues only in the ras and mos transformed cells but not in untransformed NIH3T3 cells, was identical to the previously described GAP-associated tyrosine phosphoprotein, p62, that is the major target for phosphorylation in cells transformed by tyrosine kinase oncogenes . These results suggest that agents such as radicicol can suppress transformation by diverse oncogenes such as src, ras and mos at least in part by inhibiting the function of key signal transduction intermediates such as MAP kinase and GAP-associated p62. JAMA, 1995 Jul 5, 274(1), 66 - 8 Pitfalls in the diagnosis and treatment of Lyme disease in children; Feder HM Jr et al.; OBJECTIVE--To define pitfalls of diagnosis and treatment of Lyme disease in children . DESIGN--Case series . SETTING--A university Lyme disease clinic in a Lyme disease endemic area . PATIENTS--A total of 146 pediatric patients (mean age, 9.9 years) referred with possible Lyme disease . MAIN OUTCOME MEASURES--Of the 146 patients, 56 (38%) were overdiagnosed, 12 (8%) were underdiagnosed, and 75 (51%) were correctly diagnosed with Lyme disease . Treatment errors were made for 19 (25%) of these 75 patients . In addition, three patients (2%) with tick bites were misdiagnosed or mistreated . Frequent pitfalls included misidentifying rashes as erythema migrans, ascribing nonspecific symptoms to Lyme disease, failing to ascribe fleeting objective symptoms to Lyme disease, and inappropriate antibiotic therapy for patients with Lyme disease . CONCLUSIONS--Errors in the diagnosis and treatment of Lyme disease in children are common. Microb Drug Resist, 1995 Summer, 1(2), 159 - 62 Acute and chronic bronchitis; Carbon C; Although questions persist on the precise role of infection in acute exacerbations of chronic bronchitis and on the overall benefit of antibiotic therapy of acute episodes, antibiotic therapy is considered an important part of the management of patients . It has to obey precise rules and obviously must be associated with preventive measures that can help to reduce both frequency and severity of acute exacerbations . The modifications of the susceptibility pattern to antibiotics of the two main bacteria involved deserve special attention to control the extension of the problem and define new therapeutic strategies . At present the currently recommended regimens are still valuable. Int Surg, 1995 Jul-Sep, 80(3), 239 - 41 A simple management of mediastinitis; Pasaoglu I et al.; Between January 1, 1986 and December 31, 1993, 6940 open heart procedures were performed via median sternotomy at Hacettepe University Medical Center . Mediastinitis developed in 55 patients (0.79%) . Twenty-four were children . All were reoperated for treatment of mediastinitis . Following radical debridment 17 were irrigated with dilute povidone-iodine solution after primary reclosure (Group A), the remaining 38 were simply reclosed while leaving just drains in the mediastinum (Group B) . Hospital mortality was 17.65% in Group A and 15.79% in Group B . Time of hospitalization after treatment in living patients was 17.6 days in Group A and 16.3 days in Group B . A mortality of 15.79% is an acceptable result which shows early radical debridment and drainage of the mediastinum is the most important cornerstone of the treatment of mediastinitis and is mostly enough with proper systemic antibiotic therapy. Cancer, 1995 Jul 1, 76(1), 116 - 20 Infusion site soft-tissue injury after paclitaxel administration; Bicher A et al.; BACKGROUND . Paclitaxel is a diterpenic plant product that has significant activity in several solid tumors, including epithelial ovarian cancer . After promising results in Phase I and II studies, its use has increased dramatically . With this increased use, isolated reports of local tissue reactions to paclitaxel have been described . The purpose of this study was to characterize further the presentation and clinical course of this toxic effect . METHODS . Nine hundred fifty-five courses of paclitaxel were administered to patients with gynecologic malignancies at M . D . Anderson Cancer Center during a 13-month period . Nineteen (2%) local infusion-site injuries in 17 patients were observed . RESULTS . The primary disease site was the ovary in 13 patients, the peritoneum in 2, and the endometrium in 2 . Paclitaxel was administered as initial therapy in 6 patients and as salvage therapy in 11 . Clinical evidence of infiltration was documented during infusion in 8 of 19 (42%) reported episodes . Immediate reactions consisting of mild discomfort, erythema, and edema were observed in six patients, three of whom had complete resolution of the lesion within 1 month . The remaining patients noted initial development of injury between 3 and 13 days after paclitaxel infusion . The typical injury was a discolored, raised, rounded, and indurated lesion that was moderately painful . Two patients (11%) had Grade 1 lesions, 13 (68%) had Grade 2 lesions, and four (21%) had Grade 3 lesions with central ulceration . Cellulitis requiring intravenous antibiotic therapy was associated with two lesions . At last follow-up, 13 injuries had persistent discoloration and induration; one patient had persistent ulceration present at the time of her death 6 months after presentation and one patient underwent excision of a persistent lesion at 12 months . CONCLUSIONS . Given the incidence of Grade 2 and Grade 3 local reactions, it appears that paclitaxel should be considered a vesicant. Curr Genet, 1995 Jul, 28(2), 190 - 6 A method for easy isolation of promoter fragments from promoter-probe libraries of filamentous fungi; Weltring KM; Two genomic fragments capable of driving the expression of the hygromycin B resistance gene (hph) were isolated from the phytopathogenic ascomycete Gibberella pulicaris (anamorph Fusarium sambucinum) using a "promoter-probe library" strategy . Two libraries consisting of random, 0.5-2.0-kb fragments of genomic DNA inserted 5' of a promoterless hph gene were constructed and used for transformation of G . pulicaris . Both libraries transformed G . pulicaris at a low frequency . Transformants tolerated up to 800 micrograms/ml of hygromycin B, while untransformed colonies were inhibited completely by 50 micrograms/ml of the antibiotic . Plasmids were re-isolated from transformants by simply digesting, the genomic DNA with KpnI, which cuts once in the polylinker 5' to the insert, and transforming E . coli with the re-ligated DNA . The recovered plasmids transformed G . pulicaris with a frequency of up to 4.4 transformants/micrograms of DNA . Both promoter fragments were sequenced and found to contain TATA and CAAT boxes as well as CT-rich sequences . This method makes it possible to easily isolate many fragments with promoter activity from filamentous fungi, and should facilitate the investigation of the promoter structures necessary for the expression of fungal genes. Proc Nutr Soc, 1995 Jul, 54(2), 579 - 90 The Sir David Cuthbertson Medal Lecture . Enteral-feeding-related diarrhoea: proposed causes and possible solutions; Bowling TE; So to summarize the key points: 1 . concomitant antibiotic therapy, infected diets and possibly hypoalbuminaemia can lead to enteral-feeding-related diarrhoea; 2 . the small intestinal responses to both intragastric and intraduodenal enteral feeding are normal and predictable; 3 . there is an ascending colonic secretion during enteral feeding which is more profound during intragastric feeding; 4 . the suppression of distal colonic motor activity occurs only during high-load feeding and is probably a secondary phenomenon to the hormonal and secretory responses; 5 . peptide YY appears to be intrinsically bound up with the causation of the secretory effect; 6 . the secretory effect is abolished by intracaecal SCFA. Blood, 1995 Jul 1, 86(1), 101 - 10 Analysis of optimal conditions for retroviral-mediated transduction of primitive human hematopoietic cells; Nolta JA et al.; We sought to define optimal conditions for retroviral-mediated transduction of long-lived human hematopoietic progenitors from bone marrow and peripheral blood . CD34+ cells were transduced by the LN and G2 retroviral vectors in the presence or absence of stromal support and with or without cytokine addition . After transduction, a portion of the cells was plated in methylcellulose colony-forming assay, with or without G418, to assess the extent of gene transfer into committed progenitors . The remaining cells from each experiment were transplanted into immunodeficient mice to allow analysis of transduction of long-lived progenitors . Human colony-forming cells contained within the murine bone marrow were analyzed after engraftment periods of 2 to 11 months . Cells were plated in a human-specific colony-forming assay with and without G418 to assess the extent of transduction of primitive progenitors . Individual human colonies were also analyzed by polymerase chain reaction for the presence of provirus . Bone marrow progenitors were efficiently transduced only when stroma was present, whereas mobilized peripheral blood progenitors were effectively transduced in the presence of either stroma or cytokines . Inclusion of the cytokines interleukin-3, interleukin-6, and stem cell factor did not further augment the extent of gene transfer in the presence of a stromal support layer . Additionally, human CD34+ progenitors from bone marrow or mobilized peripheral blood that had been transduced for 3 days in the absence of stroma failed to produce sustained, long-term engraftment of bnx mice . Mice transplanted with the same pools of human progenitors that had been transduced in the presence of stroma for 3 days had significant levels of human cell engraftment at the same timepoints, 7 to 11 months after transplantation . Our data show loss of long-lived human progenitors during 3-day in vitro transduction periods in the absence of stromal support . Therefore, the presence of bone marrow stroma has dual benefits