Prevalence of Helicobacter pylori infection among adult dyspeptic patients in Ethiopia

In developing countries such as Ethiopia, where chronic gastritis and peptic-ulcer disease are the most common endoscopic findings, it is important to study the association between Helicobacter pylori infection and gastroduodenal diseases. Both invasive and non-invasive diagnostic methods were therefore used to investigate 300, consecutive, adult patients with dyspepsia, from the gastrointestinal clinic of Tikur Anbassa University Hospital, Addis Ababa. The apparent overall prevalence of H. pylori infection varied according to the detection method employed. Culture revealed H. pylori in only 69% of the patients but this pathogen appeared more common when rapid urease tests (71%), PCR-denaturating gradient gel electrophoresis (91%), histopathology (81%), silver staining (75%) or stool-antigen tests (81%) were employed. Antibodies to H. pylori were detected, both by enzyme immuno-assay (EIA) and immunoblotting, in approximately 80% of the patients, whether the antigens used were of a reference strain or from a local isolate of H. pylori. When some of the EIA-positive and EIA-negative sera were cross-absorbed with antigens of Campylobacter jejuni and re-tested by EIA, the H. pylori-positive sera remained positive and the negative sera remained negative. Dyspeptic patients in Ethiopia, like most of those previously observed elsewhere in Africa, are often infected with H. pylori. It is important that the management of these patients should not be hampered by the misinterpretation of the African epidemiology of this pathogen.     

Ultrasonographical investigations of onchocerciasis in Liberia

The efficiency of ultrasonography (US) for the diagnosis and clinical characterization of onchocerciasis was evaluated. US was performed on 120 probands in Liberia. Ninety-two patients had generalized onchocerciasis, 21 patients suffered from the chronic hyperreactive form of onchocerciasis (sowda), and 7 probands served as controls. Patients were examined by US with linear (7.5 MHz and 5 MHz) and sector (3.5 MHz) scanners. US results were evaluated by examination of extirpated nodules. The US structure of nodules revealed a typical pattern consisting of a homogeneous echogenicity with small echodense particles and a lateral acoustic shadow, and differentiation from lymph nodes, lipoma, or fibroma was achieved. Within the onchocercomata, calcifications or fluid were identified. Regarding the estimation of the worm burden, it is important to note that in 24 patients, additional nodules not previously palpated were found by US. Also, the number of worm centers in palpable conglomerate nodules were determined more exactly by US than by palpation. In 4 of 16 sowda patients, impalpable nodules were found by US. In 13 patients with positive microfilaria counts, no nodules could be detected. The highly characteristic ultrasonographical pattern of onchocercomata may serve as a basis for further US investigations in onchocerciasis.     

Antihypertensive therapy and improved life expectancy without cerebrovascular accident or coronary artery disease

The absolute benefit from antihypertensive therapy increases with the baseline risk. However, age is a major determinant of cardiovascular risk, so it is important to express therapeutic efficacy with indices for which age is not a confounder. With this aim we explored the expected gain in life expectancy without cardiovascular events according to age at the initiation of the treatment. The treatment effect estimated from the INDANA meta-analysis, was applied to the cardiovascular risk of a French hypertensive population, simulated from national vital statistics. The gain in life expectancy was estimated from the area between survival curves without events. The treatment effect varied according three different hypotheses: increasing, decreasing or constant effect. When assuming a constant treatment effect, our results show a 29 month gain without stroke for a man who began his treatment at 40 years, and 15 months if hypertension is screened and treatment initiated at 75 years. The gains without coronary heart disease are respectively of 11 and 6 months. The variation of treatment effect over time could have a major impact on the treatment benefit. The gain in life expectancy without events is a relevant decision tool, completing usefully the absolute benefit, since it takes into account the influence of age.     

Tumour marker CA125 levels in a variety of benign and malignant conditions

The levels of tumour marker CA125 were established in 515 patients with a variety of benign and malignant conditions. With a specificity of 60.3% and an overall sensitivity for malignant tumours of 54% (extra-ovarian serous papillary carcinomas 100%), it is the most reliable tumour marker at present available for epithelial ovarian cancer and is of considerable value in the management of this condition when considered in conjunction with other clinical measurements.     

Changes of acetylcholinesterase activity in various parts of brain following nontreated and treated soman poisoning in rats

Changes of acetylcholinesterase (AChE) activity in various parts of the brain (frontal cortex, medulla oblongata., pons Varoli, cerebellum, hypothalamus, and hippocampus), following im sublethal nontreated and treated soman poisoning were studied. As a treatment, two antidotal mixtures containing atropine and either obidoxime or oxime HI-6 were used. This antidotal treatment was administered im for 30 s following soman intoxication. The AChE activities in the various brain tissues were evaluated at 1 and 3 h following soman administration. As expected, the highly toxic organophosphorus compound, soman, markedly inhibited AChE activity in all the brain sections at both time intervals. Both oximes had little influence on soman-induced AChE inhibition, but only the HI-6 mixture was able to reactivate soman-inhibited AChE significantly in some of the brain parts (frontal cortex, pons Varoli, hypothalamus). In the brain, the effect, of HI-6 against soman.-induced AChE inhibition is higher in comparison with obidoxime, but not quite satisfactory. Despite its limited effectiveness in the brain, HI-6 seems to be the most effective oxime yet found against soman poisoning because of its high reactivating effect in the peripheral, compartment and other beneficial effects.     

In vitro reactivation potency of some acetylcholinesterase reactivators against sarin- and cyclosarin-induced inhibitions

In our study, we have tested six acetylcholinesterase (AChE) reactivators (pralidoxime, obidoxime, HI-6, trimedoxime, BI-6 and Hl?-7) for reactivation of sarin- and cyclosarin-inhibited AChE using an in vitro reactivation test. We have used rat brain homogenate as the suitable source of enzyme. All oximes are able to reactivate sarin-inhibited AChE. On the other hand, only HI-6 is able to reactivate satisfactorily cyclosarin-inhibited AChE.