Extracellular metal-binding activity of the sulphate-reducing bacterium Desulfococcus multivorans

Polarography was used to measure the copper-binding ability of culture filtrates from a range of sulphate-reducing bacteria (SRB), including pure cultures and environmental isolates. Of those tested, Desulfococcus multivorans was shown to have the greatest copper-binding capacity and this organism was used for further experiments. Extracellular copper- and zinc-binding activities of Dc. multivorans culture filtrates from batch cultures increased over time and reached a maximum after 10 d growth. The culture filtrate was shown to bind copper reversibly and zinc irreversibly. Twelve-day-old Dc. multivorans culture filtrates were shown to have a copper-binding capacity of 3.64 +/- 0.33 micromol ml(-1) with a stability constant, log10K, of 5.68 +/- 0.64 (n=4). The metal-binding compound was partially purified from culture growth media by dichloromethane extraction followed by HPLC using an acetonitrile gradient.

Evaluation of a new once-daily formulation of oxbutynin for the treatment of urinary urge incontinence. Ditropan XL Study Group

OBJECTIVES

To evaluate in a 1 6-center, single-treatment study once-daily controlled-release oxybutynin (Ditropan XL) for urinary urge incontinence.

METHODS

Two hundred fifty-six participants with urge incontinence or mixed incontinence with a significant urge component were treated. After baseline measurements, participants converting from conventional oxybutynin started Ditropan XL at their previous oxybutynin dose; others started at 5 mg/day. Doses were adjusted until participants reached a maintenance dose that produced continence or the best balance between continence and side effects. This dose was continued for 12 weeks. Effectiveness was assessed by urinary diaries.

RESULTS

Effectiveness was achieved across all doses studied (5 to 30 mg/day), with 70.8% of participants using maintenance doses of 5 to 15 mg/day. Mean urge incontinence episodes per week decreased from 18.8 at baseline to 3.9 in maintenance week 1, 2.7 in week 4, and 2.8 at the end of the study. For those participants who reported urge incontinence episodes at baseline but were free of urge incontinence at maintenance week 1, 31% remained free of urge incontinence at every subsequent assessment. Participants who converted from other medications showed symptomatic improvement after conversion. At some time during the study, 58.6% of participants reported dry mouth, with 23.0% of participants rating it moderate or severe. Only 1.6% of participants discontinued the medication because of dry mouth.

CONCLUSIONS

Ditropan XL treatment reduced the number of incontinence episodes. Maximum benefit was demonstrated by maintenance week 4 and was sustained through 12 weeks of maintenance therapy.

Rural health. Country strife

Funding mechanisms in the NHS need to take more account of rurality in allocating funds. Rurality is considered in allocating funds to other public services such as the police, education and district council services. Country areas have more, and smaller, hospitals than cities, and this involves extra costs.

Anastomotic pulmonary hypertension after lung transplantation for primary pulmonary hypertension: report of surgical correction

This report describes a patient who developed pulmonary hypertension 6 years after lung transplantation for primary pulmonary hypertension (PPH). Evaluation with right heart catheterization followed by pulmonary angiography, however, demonstrated that the pulmonary hypertension was secondary to an anastomotic narrowing of the pulmonary artery, rather than a recurrence of her PPH. Vascular complications of lung transplantation should be considered in patients who experience exertional dyspnea after lung transplantation. The suggestion of pulmonary hypertension on echocardiography should prompt further evaluation, including meticulous hemodynamic measurements.

Effects of aggressive cholesterol lowering and low-dose anticoagulation on clinical and angiographic outcomes in patients with diabetes: the Post Coronary Artery Bypass Graft Trial

Diabetic patients have greater risk for coronary heart disease (CHD) events after coronary artery bypass graft (CABG) surgery than nondiabetic patients. The Post CABG trial studied the effects of aggressive cholesterol lowering and low-dose anticoagulation in diabetic patients compared with nondiabetic patients. A double-blind, randomized clinical trial in 1,351 patients (1-11 years after CABG), the Post CABG trial consisted of two interventions (aggressive cholesterol-lowering versus moderate lowering and low-dose warfarin versus placebo) on angiographic end points. Angiographic changes in saphenous vein graft conduits 4.3 years after entry were compared in 116 diabetic and 1,235 nondiabetic patients. Seven clinical centers participated in the trial, as well as the National Institutes of Health project office (National Heart, Lung, and Blood Institute), the coordinating center (Maryland Medical Research Institute), and the Angiogram Reading Center (University of Minnesota). Baseline characteristics of the diabetic patients differed from the nondiabetic patients in the following ways: percentage of women participants, 15 vs. 7%, P = 0.002; mean baseline weight, 87.4 vs. 82.8 kg, P = 0.006; mean BMI, 29.5 vs. 27.6 kg/m2, P = 0.0002; mean systolic blood pressure, 141.7 vs. 133.6, P < 0.0001; mean triglyceride concentrations, 2.09 vs. 1.77 mmol/l, P < 0.0001; and mean HDL cholesterol concentrations, 0.93 vs. 1.02 mmol, P = 0.0001. The percentage of clinical events was higher in diabetic than nondiabetic patients (20.6 vs. 13.4, P = 0.033) and angiographic outcomes were not different. The benefits of aggressive cholesterol lowering were comparable in diabetic and nondiabetic patients for the angiographic end points. Warfarin use was not associated with clinical or angiographic benefit. Diabetic patients in the Post CABG trial had more CHD risk factors at study entry and higher clinical event rates during the study than nondiabetic patients. The benefits of aggressive cholesterol lowering in diabetic patients were comparable to those in nondiabetic patients for both angiographic and clinical end points. The small number of diabetic patients provided limited power to detect significant differences between diabetic and nondiabetic patients or between diabetic patients in the aggressive versus moderate cholesterol treatment strategies.

Rheolytic thrombectomy: a new treatment for stent thrombosis

Coronary stent thrombosis, a rare complication after stent deployment, carries major morbidity and mortality. Traditional treatments for stent thrombosis include local or systemic delivery of thrombolytic agents and balloon angioplasty, both with far from optimum results. We report on two cases of coronary stent thrombosis successfully treated with rheolytic thrombectomy as an adjunct to balloon angioplasty.

Domestic aeroallergen exposures among infants in an English town

A multicentre, prospective cohort study of childhood asthma was established in three European countries; the purpose of the project is the examination of factors which modify the relationship between allergen exposure in infant life and subsequent atopy and asthma. Dust samples were collected from the homes of 643 infants in a single town in the UK (the first cohort) and assayed for house dust mites (Der p 1) and cat allergen (Fel d 1) concentrations by enzyme-linked immunosorbent assay. A questionnaire with potential relevance to the development of atopy and asthma was completed. A wide variation in exposure to both allergens was observed. Carpeted, double-glazed or damp living rooms, and those sampled in the winter months, had higher levels of Der p 1, but these features did not predict Fel d 1 concentrations. Measures of high home occupancy were positively related to Der p 1 concentrations; and inversely with levels of Fel d 1, a finding which could not be explained by cat ownership. Homes in which one or more persons smoked had significantly lower concentrations of Der p 1, but not Fel d 1. There were no consistent differences in allergen levels between homes where one or more parent or sibling was either atopic or asthmatic. These findings indicate complex interactions among domestic, behavioural and seasonal factors and early allergen exposure in British children.

Lymph node tuberculosis in the suburbs of Paris: 59 cases in adults not infected by the human immunodeficiency virus

We report 59 cases of lymph node tuberculosis in adults not infected by the human immunodeficiency virus (HIV), observed over a period of 5 years in the North Eastern suburbs of Paris. There were 31 women and 28 men; 84.7% were aged under 44 years; 69.5% were not French, and 78% had exclusive lymph node tuberculosis. A superficial distribution was found in 52 cases and a deep pattern in 17 cases. Cervical and supraclavicular lymphadenopathies were the most common (64.4%). General symptoms were present in 63% of cases. The diagnosis was established by fine needle aspiration in 10 cases and by biopsy in 36 cases. Three cases of primary resistance to anti-tuberculosis therapy were described. Lymph node tuberculosis is still present in the Paris region, independently of HIV infection, probably due to poor social conditions.

Chlamydia in a district general hospital: an audit of treatment and contact tracing

A retrospective case note audit, with reference to the recently published central audit group guidelines, was undertaken to assess females with chlamydial infection attending a district general hospital department of genitourinary medicine. Those diagnosed and referred by other agencies (mainly general practitioners (GPs)) were more often symptomatic and those treated before attending was more likely to need retreating. Contact tracing for current and recent partners was more successful than tracing previous partners. We feel that GPs and other agencies should continue to be encouraged to diagnose chlamydial infection and then to refer for immediate management, to limit re-infection/ potential re-infection and the need for retreatment. Contact tracing of casual contacts and previous partners has been of limited success and poses a challenge to meet the standards of the new guidelines.

Electrophysiological characterisation of the human N-type Ca2+ channel III: pH-dependent inhibition by a synthetic macrocyclic polyamine

The effects of a novel synthetic macrocyclic polyamine (LY310315) were investigated on recombinant human N-type Ca2+ channels stabley expressed in HEK293 cells. LY310315 proved to be a potent and reversible N-type Ca2+ channel antagonist. Inhibition by this compound was dose-dependent with an IC50 of approximately 0.4 microM at pH 7.35. LY310315 blocked very rapidly at all concentrations tested. Upon washout, recovery of the Ca2+ current developed with a time constant of approximately 30 s. Use-dependence in the development of block indicated that voltage-dependent transitions in the channel protein were required to permit significant inhibition. Application of > 100 times the IC50 dose of LY310315 to the interior of the cell produced no detectable Ca2+ current inhibition. LY310315 had no effects on the kinetics of channel activation or deactivation but did slightly slow the rate of macroscopic inactivation observed during a 300 ms test depolarisation. In the presence of LY310315 the activation curve was significantly shallower. This resulted in a shift in the activation midpoint voltage to a more depolarised levels. LY310315-induced inhibition of human N-type channels was strongly dependent on the extracellular pH, with increased potency seen upon extracellular acidification. Although most effective against N-type Ca2+ channels, LY310315 was also found to inhibit both P-type and L-type Ca2+ channels. LY310315 proved to be a weak blocker of Na+ currents, but produced approximately 50% of the K+ currents of AtT20 cells at a concentration of 0.5 microM.

Increasing recruitment contacts between generalist residents at the Medical College of Georgia and rural and underserved communities

To increase the number of residents choosing to practice in rural and underserved areas, the Medical College of Georgia in 1994 created the Office of Recruitment and Retention (ORR) for generalist physicians as part of its participation in The Robert Wood Johnson Foundation's Generalist Physician Initiative. Its major purpose is to increase the contact between generalist residents and practice opportunities, especially those in rural and underserved areas. The office has helped residents better understand the resources available in rural settings and has helped these communities better understand the needs of graduates in generalist residency programs. It became a point of contact for residents and communities. It also organized on-campus "practice opportunity fairs" that permitted community representatives to meet formally with generalist residents to provide information on practice opportunities and community resources. The office organized practice management sessions and provided legal consultation to residents desiring to enter private practice in rural settings. This program has already been instrumental in furthering contact between generalist residents and the rural communities they selected as clinical practice sites during training. Although it is too early to know the impact of these activities, communities increasingly use the office to recruit generalist physicians, and residents use it to identify appropriate practice sites.