Training for excellence in the inner city: an interview with Richard Savage and Clare Vaughan. Interview by Douglas Carnall.

Recruitment to general practice is at its lowest level for 30 years, and many vocational training schemes report difficulty in attracting new trainees. Spurred on by the aging population of south London, and with the advantage of pounds 1.3m of development money resulting from the Tomlinson report, the south London organisation of vocational training schemes (SLOVTS) has perhaps been able to cope better than most. Its chair, Richard Savage, a general practitioner and course organiser, and Clare Vaughan, an assistant adviser, have devised and implemented many innovative training posts for general practice over the past two years, and their approach seems to be bearing fruit: most of the doctors who have finished the training scheme are now entering practice in south London. They talked to Douglas Carnall about the causes of the crisis and the measures they have implemented to counter it. Clare Vaughan died in the week following the interview (see obituary, p 555).     

Early-replication DNA patterns in a derivative chromosome in a syrian hamster with only 42 chromosomes

From crosses within a 2n = 43 line of Syrian hamsters (Mesocricetus auratus) lacking one derivative (der 11) of an 11;20 reciprocal translocation we have obtained homozygotes with only 42 chromosomes These animals are homozygous deficient (nullisomic) for the centromere and short arm of chromosome 11 and for the bulk of the long arm of chromosome 20. — During cytogenetic studies, we investigated the frequency patterns of early-replicating bands in the surviving derivative (der 20) at two cytologically defined sub-phases of S using short-term fibroblast cultures. These patterns were compared with those observed in the component, untranslocated arms in normal 2n = 44 cells at the same two sub-phases. — Very close agreement was found, indicating that neither the nullisomy, nor the new arm combination has interfered detectably with the pattern or programme of early band replication.     

The endocrinology of puberty and reproductive functioning in female cotton-top tamarins (Saguinus oedipus) under varying social conditions

Sexual maturation and fertility were assessed in fourteen cotton-top tamarin (Saguinus oedipus) females under various social conditions. Six tamarin females (20-28 mo of age) showed a suppression of fertility while living with their families. Hormonal profiles demonstrated low, acyclic levels of urinary luteinizing hormone (LH) and estrone-conjugates (E1C). A rapid onset of ovarian and pituitary cyclicity occurred when four of the six females were removed from their families and paired with an unrelated male. In one female, an ovulatory LH peak occurred as early as eight days after pairing and resulted in conception and full-term pregnancy. Two of the six females were housed in total isolation for 30 days following their removal from the family and prior to pairing. Gradual increases in hormone concentrations occurred during isolation; however, there was no ovarian cyclicity until each female was paired with an unrelated male. In all six females, conception occurred before or as a result of the third ovulatory cycle. Partial isolation of a 36-mo-old female resulted in elevated LH and E1C levels, but cyclicity was not observed until the female was paired with an unrelated male. These findings indicate that removal of a female from the family alone does not initiate ovarian cycling. Sexual maturation, or puberty, occurs in female tamarins living with their families between 15 and 17 mo of age when mean LH and E1C levels began to increase. However, when a female is removed and paired at 9 mo of age with an unrelated male, elevated levels of LH and E1C may be seen by 10 and 11 mo of age. Our findings indicate that a suppression of fertility occurs in cotton-top tamarins living with their families, but that reproductive suppression does not affect the process of sexual maturation. Both removal from the family environment and stimulation by an unrelated male tamarin were necessary to induce normal reproductive activity. An acceleration of puberty occurred when a female tamarin was removed from her family early in development and paired with a male.     

Standardized method for evaluation of hand disinfection by surgical scrub formulations

A standardized protocol for the evaluation of hand disinfection by surgical scrub formulations was applied to volunteers in a multicenter trial. Povidone iodine (PVI), chlorhexidine (CHX), and a nonmedicated soap (NMS) were tested. The scrubbing procedure involved three daily hand washings for five consecutive days; surviving bacteria were counted daily after being collected in a suitable neutralizing solution. Immediate efficacy (IE), cumulative efficacy (CE), and remanent effect (RE) were calculated by reference to the control hand. Statistical analyses of IE, CE, and RE showed significant differences among the three scrub formulations. IEs of PVI and CHX were equivalent and different from IE of NMS; CE and RE of CHX were higher than those of PVI and NMS. On the basis of the statistical analysis, the population size required for further studies aimed at detecting significant differences between surgical scrub formulations could be estimated.     

Genetic transformation in Lactobacillus sp. strain 100-33 of the capacity to colonize the nonsecreting gastric epithelium in mice

Lactobacillus isolates able to colonize the surfaces of the nonsecreting epithelia in the stomachs of monoassociated ex-germfree mice were derived from Lactobacillus acidophilus 100-33. Strain 100-33 was originally isolated from pig feces and is unable to colonize the murine gastric epithelium. In experiments involving attempts genetically to transform the capacity to colonize the epithelium, cells of strain 100-33 were treated with muralytic enzymes and mixed with polyethylene glycol and genomic or plasmid DNA extracted from Lactobacillus fermentum RI. Strain RI was originally isolated from a conventional mouse and has the capacity to colonize the nonsecreting gastric epithelium. The mixtures containing cells, polyethylene glycol, and DNA were plated on a regeneration medium. After overnight incubation, the cells were washed from the plates and introduced by gastric gavage into germfree mice. Only mice that received regenerated 100-33 cells previously mixed with genomic DNA from strain RI had layers of gram-positive bacteria on the keratinized epithelia of their stomachs. Six isolates cultured from the washed gastric tissues of these animals were characterized. When a culture of each or a pool of cultures of the six were orally administered to germfree mice, layers of gram-positive bacterial cells were visible on the keratinized gastric epithelia of the animals within 1 to 3 weeks. Cells of all six, but not of strain 100-33, reacted with antibody made in rabbits to L. fermentum RI cells, as determined by an enzyme-linked immunosorbent assay. Nevertheless, all six had fermentation profiles identical to that of strain 100-33.(ABSTRACT TRUNCATED AT 250 WORDS)     

Degradation of DNA in cells and extracts of the obligately anaerobic bacterium Roseburia cecicola upon exposure to air.

High-molecular-weight chromosomal DNA from Roseburia cecicola, an oxygen-intolerant anaerobe, could be isolated only when the bacterial cells were kept under anaerobic conditions up to the time of cell lysis. When the cells were exposed to oxygen before lysis, the chromosomal DNA degraded. Likewise, linear but not covalently closed circular DNAs degraded in cell extracts of the organism that were exposed to atmospheres containing O2 but not in extracts that were maintained in a reduced state. Covalently closed circular DNAs were nicked but not degraded in the oxidized extracts.