In vitro activities of the oxazolidinone antibiotics U-100592 and U-100766 against Staphylococcus aureus and coagulase-negative Staphylococcus species

U-100592 and U-100766 are closely related antibiotics of the oxazolidinone class. Their in vitro activities were determined against 100 isolates of Staphylococcus aureus and 100 isolates of coagulase-negative Staphylococcus species by broth and agar dilution test methods. The MICs of both compounds by either test method at which 50 and 90% of isolates are inhibited were 2 and 4 micrograms/ml, respectively, for S. aureus and 1 to 2 micrograms/ml for coagulase-negative staphylococci. Time-kill assay with selected strains indicated a primarily bacteriostatic effect against staphylococci.     

Chemical speciation of lead dust associated with primary lead smelting

The research presented in this article assessed geochemical factors relating to dust produced during primary lead smelting. Bulk dust samples and size-selective airborne dust samples were collected from four areas of a primary lead smelter and analyzed by X-ray diffraction and sequential chemical extraction. X-ray diffraction showed that the smelter dusts were composed primarily of sulfides, oxides, sulfates, and silicates of metal ores, with galena being the primary dust component. Sequential extraction revealed the solubility of lead compounds at less than 7% in the exchangeable and mildly acidic steps for the bulk dusts collected from four smelter areas. The later steps of the extraction procedure were more effective in dissolving the lead compounds associated with the bulk dust samples, with 43%, 26%, and 8% of the total lead, in the ore storage, sinter, and blast/dross smelter areas, respectively, being extracted in the residual step. Sequential extraction of coarse airborne dust samples from the ore storage and sinter plant showed that 1.2% and 4.1% of the total lead, respectively, was exchangeable. The finer particle size fractions from these areas of the smelter showed higher percentages of exchangeable lead. Of the course airborne dust from the blast/dross furnace processes, 65% of the total lead was exchangeable. However, the largest percentage of lead from these areas was associated with the finer particle-size fractions. If lead bioavailability is related to its solubility as determined through sequential extraction, the health hazards associated with lead exposure may be appreciably enhanced in the blast and dross furnace processes.     

Macroaspartasemia as a cause of isolated elevation of aspartate aminotransferase--its biochemical and physiological characteristics

The effects of a physical activity intervention on strength, balance, motor coordination, and mobility were tested in a quasi-experiment at rural congregate nutrition sites. Twice-weekly sessions of low intensity movements were conducted for one year. Logistic regression results showed significant differences between intervention (n = 61) and comparison (n = 49) groups on several performance-based measures. Intervention subjects perceived significantly greater improvements in physical functioning over the previous year than did comparison subjects. A qualitative evaluation revealed perceived program benefits of pain reduction, increased flexibility, muscle strengthening, increased walking speed, and improved mental outlook.     

Idiopathic retroperitoneal fibrosis presented as an abdominal mass and nephrotic syndrome

We present a 30-year-old male patient who was initially diagnosed as minimal change nephrotic syndrome, 5 years later, the patient developed a localized form of idiopathic retroperitoneal fibrosis (IRF). An elevated ESR and concomitant nephrotic syndrome in the patient suggested the immunologic nature of IRF, IRF has been reported in association with collagen diseases and rarely with proliferative and nonproliferative glomerulopathies. To our knowledge, the association between minimal change lesion (MC) and IRF has not been reported. Furthermore, the fact that IRF presented itself as an abdominal mass and lacked systemic symptoms was also unusual.     

Consultations with practitioners of alternative medicine

More than 2,000 Jewish adults, aged 45-75, in urban areas of Israel were interviewed regarding consultations with practitioners of alternative medicine. 6% (122) of the respondents reported visiting such practitioners in the year prior to the interview. Homeopathy was the most frequent therapy, followed by reflexology, naturopathy, and acupuncture. The most common medical complaint was pain, particularly back pain. The most frequent reason for consulting the practitioner was disappointment with the outcome of conventional treatment. 39% of respondents who visited a practitioner were being treated by a conventional physician at the same time, for the same problem. The medical problems of a large majority had been relieved, but 22% said they were not helped by the practitioner. Women were more likely than men to consult a practitioner. Respondents with secondary or higher education were more likely to visit than those with less education. There were no age or socio-economic differences between users and nonusers. The mean payment for the whole series of treatments was NIS 770 (about $250). Respondents who visited practitioners reported worse health and more pain than nonusers, and were also more likely to have visited their conventional primary care physician in the past month. The findings suggest that nonconventional medicine should be seen as complementary to, rather than in competition with conventional medicine.     

In vivo activities of ceftriaxone and vancomycin against Borrelia spp. in the mouse brain and other sites

Borrelia burgdorferi, the agent of Lyme disease, and B. turicatae, a neurotropic agent of relapsing fever, are susceptible to vancomycin in vitro, with an MIC of 0.5 microgram/ml. To determine the activity of vancomycin in vivo, particularly in the brain, we infected adult immunocompetent BALB/c and immunodeficient CB-17 scid mice with B. burgdorferi or B. turicatae. The mice were then treated with vancomycin, ceftriaxone as a positive control, or normal saline as a negative control. The effectiveness of treatment was assessed by cultures of blood and brain and other tissues. Ceftriaxone at a dose of 25 mg/kg of body weight administered every 12 h for 7 to 10 days eliminated cultivable B. burgdorferi or B. turicatae from all BALB/c or scid mice in the study. Vancomycin at 30 mg/kg administered every 12 h was effective in eliminating infection from immunodeficient mice if treatment was started within 3 days of the onset of infection. If treatment with vancomycin was delayed for 7 days or more, vancomycin failed to eradicate infection with B. burgdorferi or B. turicatae from immunodeficient mice. The failure of vancomycin in eradicating established infections in immunodeficient mice was associated with the persistence of viable spirochetes in the brain during antibiotic treatment.     

Interlaboratory study of the analysis of ampicillin by liquid chromatography

A liquid chromatographic method for the analysis of ampicillin was examined in a collaborative study involving seven laboratories. The method included an isocratic part, which is used in the assay. The isocratic part is similar to the assay method for ampicillin of the US Pharmacopeia XXIII Revision. When the isocratic part is combined with gradient elution, the method is suitable for purity control. Six samples of ampicillin (anhydrous, trihydrate and sodium salt) with varying purity were analysed. The main component and related substances were determined. An analysis of variance proved the absence of consistent laboratory bias. The laboratory-sample interaction was significant. Estimates of the repeatability and reproducibility of the method, expressed as standard deviations of the result of the determination of ampicillin, were calculated to be about 0.9 and 1.1 respectively.     

Risk of colorectal cancer and other cancers in patients with gall stones

Plasmodium vivax is, next to P. falciparum, the second important human malaria parasite. In view of reports on developing chloroquine resistance, research on new drugs that are active against P. vivax is necessary. Due to a requirement for continuous addition of reticulocytes, long-term in vitro culture of P. vivax is not practicable. Conventional drug assays, i.e., culturing for a time equivalent to one asexual cycle of development in the presence of drugs, and then measuring propagation, are therefore not readily performed. In this report the in vitro susceptibility of P. vivax to cyclosporin A and a new, nonimmunosuppressive derivative, SDZ NIM 811, was investigated using parasite material obtained from an infected Aotus monkey. The assay was initiated with blood containing ring-stage parasites and was ended when parasites were multinucleate, but before merozoite release. The results were compared with the in vitro susceptibility of P. falciparum to these drugs in a conventional and a short assay. As an indicator of parasite propagation [3H]hypoxanthine incorporation was measured. The susceptibility of P. vivax to cyclosporins was found to be intermediate to that of P. falciparum in the conventional and in the much less sensitive short assay, and SDZ NIM 811 proved to be as active as cyclosporin A.