Dereplication of Streptomyces soil isolates and detection of specific biosynthetic genes using an automated ribotyping instrument.

The discrimination of distinct cultures among morphologically similar Streptomyces soil isolates (dereplication) and the detection of specific biosynthetic pathways in these strains are important steps in the selection of microorganisms to include in a natural products library. We have developed methods for analysis of actinomycetes using the RiboPrinter microbial characterization system, an automated instrument that performs ribotyping on bacterial samples. To evaluate our dereplication method, 26 Streptomyces isolates, obtained from soil samples collected in Maui, Hawaii, were ribotyped and compared with each other, using the RiboPrinter. The strains were also compared by 16S rDNA sequence analysis, MIDI fatty acid analysis, and LC-MS profiling of fermentation extracts. The RiboPrinter was able to identify closely related isolates and to discriminate between morphologically similar isolates with unique genetic, fatty acid and fermentation profiles. For the detection of biosynthetic genes, a 1,006-bp probe containing a portion of an adenylation domain of a non-ribosomal peptide synthetase (NRPS) was employed. Using this alternate probe in place of the standard ribosomal probe, the RiboPrinter was able to detect NRPS genes in several strains of Streptomyces. These results demonstrate that the RiboPrinter has multiple applications in a natural products research program.

Mannopeptimycins, new cyclic glycopeptide antibiotics produced by Streptomyces hygroscopicus LL-AC98: antibacterial and mechanistic activities.

Mannopeptimycins alpha, beta, gamma, delta, and epsilon are new cyclic glycopeptide antibiotics produced by Streptomyces hygroscopicus LL-AC98. Mannopeptimycins gamma, delta, and epsilon, which have an isovaleryl substitution at various positions on the terminal mannose of the disaccharide moiety, demonstrated moderate to good antibacterial activities. Mannopeptimycin epsilon was the most active component against methicillin-resistant staphylococci and vancomycin-resistant enterococci (MICs, 2 to 4 micro g/ml for staphylococci and streptococci and 4 to 32 micro g/ml for enterococci), while mannopeptimycins gamma and delta were two- to fourfold less active. Mannopeptimycins alpha and beta, which lack the isovaleryl substitution and the disaccharide moiety, respectively, had poor antibacterial activities. The in vivo efficacies of the mannopeptimycins in Staphylococcus aureus mouse protection studies paralleled their in vitro activities. The median effective doses of mannopeptimycins gamma, delta, and epsilon were 3.8, 2.6, and 0.59 mg/kg of body weight, respectively. The mannopeptimycins were inactive against cell wall-deficient S. aureus and caused spheroplasting of Escherichia coli imp similar to that observed with penicillin G in an osmotically protective medium. Mannopeptimycin delta rapidly inhibited [(3)H]N-acetylglucosamine incorporation into peptidoglycan in Bacillus subtilis and had no effect on DNA, RNA, or protein biosynthesis. On the basis of the observations presented above, an effect on cell wall biosynthesis was suggested as the primary mode of action for mannopeptimycin delta. The mannopeptimycins were inactive against Candida albicans, did not initiate hemolysis of human erythrocytes, and did not promote potassium ion leakage from E. coli imp, suggesting a lack of membrane damage to prokaryotic or eukaryotic cells.

Saccharomicins, novel heptadecaglycoside antibiotics produced by Saccharothrix espanaensis: antibacterial and mechanistic activities.

Saccharomicins A and B, two new heptadecaglycoside antibiotics, were isolated from the fermentation broth of the rare actinomycete Saccharothrix espanaensis. They represent a novel class of bactericidal antibiotics that are active both in vitro and in vivo against bacteria and yeast (MICs: Staphylococcus aureus, <0.12 to 0. 5; vancomycin-resistant enterococci, 0.25 to 16; gram-negative bacteria, 0.25 to >128; and yeast, >128 microg/ml), including multiply resistant strains. Saccharomicins protected mice from lethal challenges by staphylococci (subcutaneous 50% effective dose range of 0.06 to 2.6 mg/kg of body weight, depending on the S. aureus strain). The 50% lethal dose by the subcutaneous route was 16 mg/kg. Mechanistic studies with Escherichia coli imp and Bacillus subtilis suggested complete, nonspecific inhibition of DNA, RNA, and protein biosynthesis within 10 min of drug treatment. Microscopic examination of drug-treated cells also suggested cell lysis. These data are consistent with a strong membrane-disruptive activity. The antibacterial activities of the saccharomicins against gram-positive bacteria were unaffected by the presence of Ca(2+) or Mg(2+), but activity against gram-negative bacteria was substantially reduced.

Biological activity of guanacastepene, a novel diterpenoid antibiotic produced by an unidentified fungus CR115.

Fermentation extracts of culture CR115, an unknown plant endophyte originally isolated from Costa Rica, were found to be active against antibiotic-resistant bacteria. The metabolite responsible for activity was identified as a novel diterpenoid antibiotic guanacastepene (mol. wt. 374.47 and mol. formula C22H30O5). Mechanistic studies done in an E. coli imp strain suggested membrane damage as the primary mode of bactericidal action. This compound also lysed human RBCs and caused leakage of intracellular potassium from E. coli imp.

Cancer and the experience of meaning: a group psychotherapy program for people with cancer.

Cancer illness affects people in many ways, physical, financial, and existential. In this paper, we describe a proposed group intervention for individuals with advanced disease who want help finding a sense of meaning at this critical juncture in their lives. This intervention has a brief, semi-structured format, and is informed by the work of Viktor Frankl, empirical findings in the area of meaning and trauma, and the empirical findings of other group interventions for cancer patients. Individual sessions focus on different aspects of meaning, including responsibility to others, creativity, transcendence, and ascertaining one's values and priorities. Having goals on which to focus and feeling like part of a larger whole are critically important to the ability to find meaning and cope with terminal illness. Such goals may be generated by a number of sources, including connectedness with others, or a sense of the temporal continuity of one's own life despite the disruption posed by severe illness. Didactic discussions and experiential exercises help to facilitate exploration of these various elements in group members' lives. The finite structure of the intervention may also highlight these issues, as people who are faced with similar issues work together in a limited time frame in order to accomplish the goals they set out for themselves.

The house that's on fire: meaning-centered psychotherapy pilot group for cancer patients.

People with advanced cancer face an existential crisis in addition to their physical suffering. The principles of a new group therapy intervention (MCGP) were introduced in another paper in this issue. This paper is a report of some of the themes and issues that arose during the first pilot group.

Novel polyketide metabolites from a species of marine fungi.

Fermentation of a marine fungal species obtained from a tissue sample of a marine sponge collected in Indonesia in October 1996, yielded the novel hexaketide compounds iso-cladospolide B (1); seco-patulolide C (2); the 12-membered macrolides, pandangolide 1 (3) and pandangolide 2 (4); and the known terrestrial fungal metabolite, cladospolide B (5).

Job satisfaction among certified and non-certified general practitioners.

BACKGROUND: The aim of family medicine is to provide patients with comprehensive care within the biopsychosocial model. High job satisfaction is necessary to attract physicians to this specialty. OBJECTIVE: To compare job satisfaction levels between primary physicians with training in family medicine and physicians without specialty training. METHODS: A self-report questionnaire, the "Task Profiles of General Practitioners in Europe," was mailed to a stratified random sample of 664 primary care physicians in Israel. The response rate was 77.6%. Bivariate and logistic regression procedures were used to analyze the data. RESULTS: Physicians with training in family medicine were less satisfied with the rewards for their work than general practitioners with no formal specialization in family medicine. Satisfaction with the intrinsic aspects of the work was found to be equal. Women and rural physicians were more satisfied than men and urban physicians. CONCLUSION: Measures should be taken by health maintenance organizations to increase the level of job satisfaction of specialist-certified family physicians to avoid a crisis in the profession.

Rotary encoding for intravascular ultrasonic imaging systems.

Images produced with an intravascular ultrasound system (IVUS) can be distorted because of uncertainty in the instantaneous angular position of a rotating ultrasonic transducer. A rotary encoder placed in proximity to the transducer is required to detect the problem; however, size constraints make a conventional electromechanical or optomechanical encoder difficult to implement. Measurements that test the feasibility of a software-derived encoder, based of the rate of decorrelation of ultrasonic RF lines with angle, are reported. Provided that the instantaneous angular velocity of the transducer can be measured, adjustments can be made to the pulse rate of the transducer, which would eliminate the image distortion.

Antibacterial leads from microbial natural products discovery.

The accidental discovery of penicillin and the advent of sulfanilamide marked the beginning of the antibiotic era. Although synthetic compounds have continued to play important roles in the fight against bacterial infections, the contribution of microbial natural products cannot be underestimated. A vast majority of the antibacterial agents in clinical use today are either microbial natural products or one of their analogs. Finding novel chemical entities with new modes of action and optimizing their activities Microbial natural products have been a proven, rich source of novel compounds with diverse biological activities. The astounding success of the 'golden' period of the antibiotic era delivered several capable of meeting the needs of that period, and subsequently, a period of diminished commitment to finding new antibiotics was experienced. An interest in microbial natural products for other therapeutic applications continued however, and has proved rewarding. The recent increase in the emergence of antibiotic-resistant bacteria has forced many to shift their attention towards finding novel antibiotics and not surprisingly, microbial natural products are being seriously pursued as a source. New antibiotics are being isolated and the old libraries of under-exploited antibiotics are being re-examined. Novel bacterial targets are being exposed through genomics and microorganisms are being genetically engineered for novel metabolites.

RBRVS--1999 update.

Medicare RBRVS has become widely used as a standard for physician fee scales by both traditional health insurance plans and managed care organizations. There are significant variations in the way RBRVS has been adapted by these private payers. These variations, when combined with annual changes Medicare has made to the underlying components of RBRVS, may result in unintended and unexpected increases in physician payments. To avoid surprises, payers using RBRVS-based fee scales need to carefully evaluate the overall impact of annual RBRVS modifications on their delivery systems.

Biosynthesis of the pyrroindomycins by Streptomyces rugosporus LL-42D005; characterization of nutrient requirements.

Streptomyces rugosporus LL-42D005 was shown to produce the novel pyrroindomycin antibiotics. Production of pyrroindomycin (alpha) and chloro-pyrroindomycin (beta) was characterized in a semi-defined fermentation medium containing glucose, casein, phosphate, vitamins and minerals. Accumulation of pyrroindomycin beta increased with increasing concentrations of glucose, reaching maximum titers at approximately 5g/L glucose. Glucose concentrations greater than 7.5 g/L decreased pyrroindomycin beta yields. Inhibition of pyrroindomycin accumulation at higher glucose concentrations could be reversed by increasing the casein concentration. Ammonium chloride, arginine or glutamine could replace casein as the sole nitrogen source for growth and pyrroindomycin production. Glucose, fructose or mannitol were utilized as the sole carbon source, while sucrose, maltose, glycerol, corn oil and starch were poorly metabolized. Incubation of this isolate in a vitamin-deficient medium resulted in a delay in growth and pyrroindomycin production; this delay was eliminated by the addition of biotin. Addition of L-tryptophan to the medium resulted in the production of pyrroindomycin alpha as the major species.

Hongoquercins, new antibacterial agents from the fungus LL-23G227: fermentation and biological activity.

Two new antibiotics, hongoquercins A and B, were isolated from fermentation extracts of the unidentified fungus LL-23G227. In the optimum medium, titers of the A and B components reached approximately 2.1 g/liter and 0.02 g/liter, respectively. The optimum temperature for antibiotic production was approximately 22 degrees C. Growth was delayed at 15 degrees C but appeared to reach higher levels than was observed at 22 degrees C. Addition of dextrose to growth media increased hongoquercin B production. Hongoquercin A exhibited moderate activity against Gram-positive bacteria. Mechanistic studies conducted in an E. coli imp strain suggested membrane damage as the primary mode of bactericidal action. These compounds also lysed human red blood cells, suggesting a similar mode of action on eukaryotic cells.

Cell wall active antifungal compounds produced by the marine fungus hypoxylon oceanicum LL-15G256. I. Taxonomy and fermentation.

The cell wall targeted antifungal activity of Hypoxylon oceanicum LL-15G256 extracts resulted from the production of novel lipodepsipeptides and previously reported macrocyclic polylactones. In an optimized medium, titers of the lipodepsipeptide and the polylactones reached approximately 200-400 mg/liter and 25-50 mg/liter, respectively. The optimum fermentation temperature for production of 15G256 gamma was 28 degrees C. Seawater appeared to have an inhibitory effect on metabolite accumulation at lower fermentation temperatures.

[Characteristics of adults with emotional distress in Israel-- patterns of mental health services used].

We sought firsthand data on the extent of perceived mental health needs and on patterns of use of mental health services among Israelis aged 22 and over. The data are from a national survey conducted in 1995. A random sample of phone numbers from the telephone company's computerized listings yielded 1,395 completed questionnaires (response rate, 81%). At some point in their lives, 27% had experienced emotional distress or mental health problems with which they had difficulty coping alone; 13.4% reported that they had such an experience during 1995. According to multivariate analysis, those more likely to report mental health problems were women, those with a chronic disease, Russian immigrants, divorced or widowed adults, those with a low level of education, and members of the Clalit sick fund. 38% of those who had ever had emotional or mental health problems had asked for help. The proportion of those seeking help was high among respondents aged 35-55, Hebrew speakers (compared to speakers of Russian or Arabic), and city dwellers, and the rate was low among members of the Clalit sick fund. Of those who did seek help, 39% went to a psychologist or a psychiatrist, 25% to their family doctor, 19% to a family member or friend, 7% to a social worker or social service agency, 6% to other medical personnel, and 4% to a psychiatric hospital. 30% turned for assistance to the private sector and 70% to the public sector. These findings have special significance in view of the impending reform of the mental health services. As mandated by the new National Health Insurance Law, mental health services are to be included in the basket of health services provided by the sick funds. The data can be of use in the management of sick funds and for physicians working in the community, as they prepare for this change. In addition, the data will be of aid to national policy makers in planning services suited to the needs of different population groups and to allocate resources more rationally.