High HIV prevalence, low condom use and gender differences in sexual behaviour among patients with STD-related complaints at a Nairobi primary health care clinic

Of 22,274 patients > or = 12 years old attending a Nairobi primary health care (PHC) clinic, 1076 (4.8%) had STD-related complaints, of whom 980 underwent assessment of risk factors for human immunodeficiency virus (HIV) infection and infrequent condom use. Gonorrhoea, chancroid, syphilis seroactivity, trichomoniasis, or objective signs of STD were found in 78%, and HIV seropositivity in 15% of men and 19% of women. Most women were married, living with a spouse; while most men were single, or married, but living separated from a spouse. Among married men, last sex was with a female sex worker (FSW) or casual partner for 60% not living with a spouse and 26% living with a spouse (P<0.005). Two or more partners during the past year were reported by 82% of men and 25% of women (P <0.001), and 55% of men and 11% of women reported the last partner was high risk. HIV seropositivity among both genders was associated with numbers of partners, and among women, with being widowed or divorced. Only 3% reported use of a condom with the last partner. Among men whose last sex was with a FSW, 74% said the reason for not using a condom was not having one. Thus, infrequent condom use, low condom availability, and gender differences in behaviour necessitate modifying development policies that separate families; and better coordination between family planning, PHC, and AIDS/STD programmes, with improved supply, social marketing and community-based distribution of condoms in high-risk settings for STD/HIV prevention.     

Abnormal colonic fermentation in irritable bowel syndrome

BACKGROUND: The cause of irritable bowel syndrome (IBS) is unknown. It may follow gastroenteritis and be associated with an abnormal gut flora and with food intolerance. Our study was designed to assess whether these factors were associated with colonic malfermentation. METHODS: We carried out a crossover controlled trial of a standard diet and an exclusion diet matched for macronutrients in six female IBS patients and six female controls. During the final 72 h on each diet, faecal excretion of fat, nitrogen, starch, and non-starch polysaccharide NSP was measured, and total excretion of hydrogen and methane collected over 24 h in a purpose-built 1.4 m3 whole-body calorimeter. Breath hydrogen and methane excretion were then measured for 3 h after 20 g oral lactulose. FINDINGS: The maximum rate of gas excretion was significantly greater in patients than in controls (2.4 mL/min IQR 1.7-2.6 vs 0.6, 0.4-1.1). Although total gas production in patients was not greater than in controls (median 527 mL/24 h IQR 387-660 vs 412, 234-507), hydrogen production was higher (332, 318-478 vs 162, 126-217, p=0.009). In patients, the exclusion diet reduced symptoms and produced a fall in maximum gas excretion (0.5 mL/min IQR 0.3-0.7). After lactulose, breath hydrogen was greater on the standard than on the exclusion diet. INTERPRETATION: Colonic-gas production, particularly of hydrogen, is greater in patients with IBS than in controls, and both symptoms and gas production are reduced by an exclusion diet. This reduction may be associated with alterations in the activity of hydrogen-consuming bacteria. Fermentation may be an important factor in the pathogenesis of IBS.     

Possible modulatory effect of browned yam flour diet on chemically-induced toxicity in the rat

The possible modulatory effect of browned yam flour, a local dietary staple in south western Nigeria, on the toxicity of 7,12-dimethylbenzanthracene (DMBA), 3-methylcholanthrene (3-MC), carbon tetrachloride (CCl4) and bromobenzene (BrB) in rats was investigated. Feeding rats with 25% browned yam flour 2 wk before treatment with 65 mg/kg DMBA (single dose) and 5 mg/kg 3-MC and continued for 3 wk significantly decreased the reduction in final body weight or weight gain and organ weights caused by the two compounds. Similarly, the diet decreased the reduction in body weight or weight gain and the increase in relative liver weight mediated by oral treatment with 0.5 ml CCl4/kg and 2.5 mmol BrB/kg body weight. Incorporation of 25% browned yam flour into rat diet significantly reduced the DMBA-mediated decrease in haemoglobin content, packed cell volume, red blood cell count and white blood cell count by 7, 5, 20 and 10%, respectively; while the diet reduced the 3-MC-mediated decrease in these parameters by 15, 28, 9 and 17%, respectively. The same diet elicited 23, 45, 13 and 33% decreases in CCl4 mediated reduction in these parameters and 23, 18, 16 and 29% in the case of BrB. Browned yam flour diet caused 10, 14 (P < 0.001) and 4% (P < 0.05) reductions in the DMBA-mediated increase in serum aspartate aminotransferase, alanine aminotransferase and serum alkaline phosphatase, respectively; and 32, 31 (P < 0.05) and 13% (P < 0.001) in the case of the 3-MC-mediated increase. Also, the diet reduced CCl4-mediated increase in the activities of these by 40, 34 and 31%, respectively and by 23, 30 and 29% following BrB treatment. These results suggest that browned yam flour diet could possibly be a modulator of chemically induced toxicity.     

Effects of age on the biomechanics and physiology of gait

There are significant changes in gait across the life span, but particularly after the age of 70 years. This article reviews the physiology of gait and the motor control challenges during gait. The kinematics (motion) and the kinetics (moment and power) of normal gait of a database of healthy young and older adults are compared. Older subjects generate significantly lower peak ankle plantar flexor power during gait. The clinical significance of the reduction in ankle plantar flexion power is discussed.     

Microangiopathy of the brain, retina, and cochlea (Susac syndrome). A report of five cases and a review of the literature

OBJECTIVE: This study reports five new cases of microangiopathy of the brain, retina, and cochlea (Susac syndrome) and reviews the world's literature. DESIGN: Five cases were systematically studied by the authors. The cases in the literature were identified through Medline searches for Susac syndrome; microangiopathy of the brain, retina, or ear; and cross-referencing the indexes of each retrieved article. PARTICIPANTS: The number of new patients studied in this report was five. An additional 41 patients were culled from the literature. INTERVENTION: Patients were treated with corticosteroids, antineoplastic agents, and other methods in a noncontrolled, nonrandomized fashion. MAIN OUTCOME MEASURES: With respect to therapeutic intervention, the main clinical outcome measures were return of vision, improvement of neurologic and psychiatric manifestations, and recovery of auditory function. Alterations of abnormalities observed by cranial magnetic resonance imaging also were monitored. RESULTS: Of 46 identified patients, 39 were women. The mean age of the patients was 30 years. Forty-one patients (89%) had arterial occlusions, which were bilateral in 60%. Thirty-one patients (67%) reported hearing loss. Twenty patients (44%) had a global encephalopathy, but other neurologic manifestations were common. The mean duration of the illness was 46.7 months. CONCLUSION: This rare syndrome is more common than previously thought, has a strong female preponderance, and often can be identified at an early stage with a careful history and physical examination. Magnetic resonance imaging of the brain often shows lesions suggestive of multiple sclerosis. Fluorescein angiography may show arteriolar wall hyperfluorescence. Early treatment with corticosteroids often is, although not invariably, associated with a good prognosis. The disease appears to be self-limited in most patients.     

Myocardial structure as a determinant of pre- and postoperative ventricular function and long-term prognosis after valve replacement for aortic stenosis

BACKGROUND: Long-term results after aortic value replacement for aortic stenosis can be correlated to a cardiac-related pre-operative risk profile. This predictability indicates that there is a common basis in subtle or overt structural abnormalities of left ventricular myocardium. METHODS AND RESULTS: Forty-nine patients aged 24-82 (mean 61) years, with aortic stenosis had a full wall thickness transmural biopsy of the left ventricular antero-lateral free wall during aortic valve replacement. Echocardiography and radionuclide ventriculography were performed prior to, and 18 months (n = 41) after, the operation. Postoperative follow-up to a maximum of 7.7 years was 100% complete. Pre-operatively, all patients had an increase in both the left ventricular mass index (202 +/- 67 g.m-2) and the muscle cell diameter (41 +/- 8 microns); other morphological data included a muscle cell nucleus volume of 752 +/- 192 microns3, a muscle cell mass index of 163 +/- 54.m-2, and a fibrous tissue mass index of 39 +/- 16 g.m-2. Patients with a pre-operative episode of clinical left ventricular failure (n = 19) had significantly greater morphological variables than those without. Pre-operative ejection fraction and other measures of systolic function correlated inversely with the morphological data, except for the fibrous tissue mass index; diastolic function indices correlated inversely with all the morphological variables. At the 18-month re-study, the same general picture was noted, but with an underlying strengthening, especially of the muscle cell mass index. Overall, the mass index dropped to 152 +/- 51 g.m-2 (P < 0.0001), but in 17% of the patients it became normal; the mass index at 18 months was directly correlated to morphological variables. A high muscle cell nucleus volume was identified as an independent predictor of early and late mortality. CONCLUSIONS: Abnormalities of the hypertrophied left ventricular muscle cell and the degree of muscle hypertrophy are, to some degree, underlying determinants of pre-operative symptomatology, pre- and postoperative ventricular function, and early and late mortality after valve replacement for aortic stenosis. Incomplete hypertrophy impaired results, was related to pre-operative myocardial structural abnormalities.     

Effect of organic loading rate on a wastewater treatment process combining moving bed biofilm and membrane reactors.

The effect of moving bed biofilm reactor (MBBR) loading rate on membrane fouling rate was studied in two parallel units combining MBBR and membrane reactor. Hollow fiber membranes with molecular weight cut-off of 30 kD were used. The HRTs of the MBBRs varied from 45 min to 4 h and the COD loading rates ranged from 4.1 to 26.6 g COD m(-2) d(-1). The trans-membrane pressure (TMP) was very sensitive to fluxes for the used membranes and the experiments were carried out at relatively low fluxes (3.3-5.6 l m(-2) h(-1)). Beside the test with the highest flux, there were no consistent differences in fouling rate between the low- and high-rate reactors. Also, the removal efficiencies were quite similar in both systems. The average COD removal efficiencies in the total process were 87% at 3-4 h HRT and 83% at 0.75-1 h HRT. At high loading rates, there was a shift in particle size distribution towards smaller particles in the MBBR effluents. However, 79-81% of the COD was in particles that were separated by membranes, explaining the relatively small differences in the removal efficiencies at different loading rates. The COD fractionation also indicated that the choice of membrane pore size within the range of 30 kD to 0.1 microm has very small effect on the COD removal in the MBBR/membrane process, especially with low-rate MBBRs.     

Design and assessment of average of normals (AON) patient data algorithms to maximize run lengths for automatic process control

Achieving high quality and high productivity with automated testing processes will require process control systems that are optimized for the necessary error detection, minimum false rejection, and maximum run length. This study investigates whether run length could be monitored by average of normals (AON) algorithms that truncate the patient test distribution and estimate the average of a suitable number of patient results. The design of AON algorithms for individual analytes is facilitated by computer-simulated power curves that consider the ratio of the population biological variation (Spop) to the test method variation (Smeas), represent a range of Spop/Smeas ratios from 2 to 15, and include numbers of patient test results from 10 to 600. The potential applications of AON algorithms are assessed for 38 tests whose quality requirements represent the total error criteria from the Ontario Medical Association Laboratory Proficiency Testing Program, Spop/Smeas ratios from 0 to 32, critical systematic shifts from 0.02 to 10.85 Smeas, and test workloads representative of a regional reference laboratory. Approximately half of these tests provide high potential for applying AON algorithms to monitor run length.