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Biomedical subjects

L Belec

Publications and source records attributed to L Belec.

At least 55 records · Page 3Linked to original sources

Leishmaniasis: report of 33 cases and a review of the literature.

Leishmaniasis are parasitic diseases in extension. They appear in new foci, because of important displacements of populations, and they affect immunocompromised patients (under chemotherapy, transplanted, or HIV infected). Study of 33 cases of leishmaniasis, 22 visceral and 11 cutaneous, at the Hôpital du Kremlin-Bicêtre, France, showed predominant contamination in Maghreb and in the south of France. In the case of Kala-Azar, fever (18 cases) and hepatosplenomegaly (19 cases) are frequent, and the serodiagnosis and the search of parasites by myelogram are always positive. In HIV-infected individuals, clinical signs are similar, but the serodiagnosis is less reliable. Evolution is bad in transplanted patients who must remain under immunosuppressive drugs. In the case of cutaneous leishmaniasis, diagnosis is based on local sample, while the serodiagnosis remains negative. Treatment is sometimes long, necessitating repeated treatments.

Allopurinol↗

Adult response to initial treatment with ampicillin in community acquired pneumonia in Yaoundé, Cameroon.

A prospective study was conducted to evaluate the efficacy of ampicillin as an initial therapy in 60 adult patients with community acquired pneumonia. Bacteriological etiology was obtained only in 24 (40pc) patients by microscopic examination, culture and antigen detection. Streptococcus pneumoniae was the leading causative agent identified in 15 cases. Other etiologies were Klebsiella pneumoniae (3), Streptococcus pyogenes (2) Staphylococcus aureus (2), Haemophilus influenzae (1) and Moraxella catarrhails (1). Patients were started on ampicillin one gram twice daily, empirically, and treated for 10 days. There were 52(86.7pc) patients cured, two(3.3pc) patients improved and six (10pc) were therapeutic failures. The causative agents in patients with failures were: Klebsiella pneumoniae (1), Staphylococcus aureus (1), Streptococcus pneumoniae (1) and unknown in three cases. Only six of 60 patients still febrile after three days were switched to amoxycillin/clavulanic acid or cefaclor according to culture results and susceptibilities or to roxythromycin because no organisms were isolated. Side effects were observed in only one (1.7pc) patient who developed a mild skin rash. Due to its low cost and its high efficacy, ampicillin still appears to be the drug of choice in adult community acquired pneumonia in our region.

Adolescent↗

[Alternative strategy for the diagnosis of HIV infection in sub-saharan Africa. Value of the sequential combination of the ELISA test and a 2nd generation rapid test].

The "conventional" algorithm for HIV testing based on the confirmation of all positive anti-HIV screening reactions by Western blot requires sufficient laboratory facilities and is expensive, that limits its use in developing countries, such as in subsaharian Africa. The apparition of second and third generation screening ELISA which are very sensitive and specific, as well as the development of rapid tests which are simple, visually read, and sufficiently sensitive and specific, has permitted the design of "alternative" strategy for HIV testing utilizing the association of 2 ELISA and/or rapid tests, in order to limit the use of a confirmatory assay. Alternative strategies are less expensive, yield generally very high sensitivity and specificity, and have proved to be valuable for African countries. In this study, 5 alternative strategies, using different associations of two second generation screening tests, one classical ELISA (Genelavia mixt) and one rapid test (Test PACK HIV-1/HIV-2 AB) have been retrospectively evaluated in the field in Bangui, Central African Republic, with a panel of 130 sera (prevalence of HIV infection: 42.7%). The strategy using two sequential screening tests (Test Pack HIV-1/HIV-2 AB following by Genelavia mixt) with the confirmation of discordant results by Western blot permitted to diagnose HIV-1 infection in Bangui with a sensitivity, a specificity and a positive predictive value of 100%, and to reduce the cost of more than 50% in comparison with the conventional strategy. Such an alternative strategy could be useful for the individual notification of HIV serology in Bangui.

Adult↗

Varicella-zoster virus encephalitis in acquired immunodeficiency syndrome: report of four cases.

Four patients with acquired immunodeficiency syndrome, a 27-year-old female intravenous drug abuser and three males (two drug addicts aged 27 and 33 years and a 40-year-old homosexual) presented with a rapidly progressive encephalopathy. Two had generalized varicella-zoster virus skin infection, one had had a regressive thoracic zoster rash 7 months previously and one had no history of cutaneous eruption. Neuropathological examination revealed, in each case, multifocal necrotic changes with numerous, intranuclear Cowdry type A inclusion bodies in glial cells, endothelial cells, macrophages and neurons, within and around the lesions. These inclusion bodies were stained positively for varicella-zoster virus by immunocytochemistry and contained herpes virus nucleocapsids by electron microscopy. Molecular biology using the polymerase-chain-reaction method demonstrated viral genome. In one case, zoster-induced non-inflammatory vasculopathy involved medium sized leptomeningeal vessels and was associated with circumscribed areas of cortico-subcortical infarction. In another case, varicella-zoster virus encephalitis was associated with human immunodeficiency virus encephalitis and a secondary cerebral lymphoma. Multinucleated giant cells expressing human immunodeficiency virus proteins in their cytoplasm, were found in the lymphomatous deposits and in the varicella-zoster virus necrotic lesions. In these latter lesions, Cowdry type A inclusion bodies could be seen in the nuclei of some multinucleated giant cells confirming previous observations of MGCs co-infected by HIV and CMV, and supporting the hypothesis that DNA viruses interact with HIV, thus increasing its effect.

Acquired Immunodeficiency Syndrome↗

[Quantitative and qualitative anomalies of sperm in African individuals infected with HIV].

Semen from 16 HIV1-infected african individuals (12 at stage II/CDC; 4 with pre-AIDS) has been analyzed both quantitatively (volume; number of spermatozoa) and qualitatively (motility). 12 healthy HIV1-seronegative individuals were recruited as controls. The HIV1-infected patients showed generally abnormalities of the semen: oligospermia (7 cases), azoospermia (3 cases), or asthenospermia (10 cases). These abnormalities were more marked in patients at advanced stages of the HIV infection. In comparison with the control group, the HIV1-infected individuals had more frequently a past history of sexually transmitted diseases. These abnormalities in the composition of the semen in HIV1-infected african individuals could affect the fertility of these men; that could indirectly restrict the risk of congenitally HIV contaminated child.

Acquired Immunodeficiency Syndrome↗

Mechanisms of failure of modular prostheses.

The expectations of wear and longevity of total hip components are based in large part on Charnley's early work. The evolution of the total hip from the one-piece, all-polyethylene acetabular component and fixed-head femoral component to the myriad of parts that comprise many of today's total hip designs has brought with it an array of potential mechanisms for failure that were not present in the earlier design. The risk/benefit ratio of these new designs may need to be reevaluated based on the additional mechanisms for failure that they provide. One hundred eleven acetabular hip prostheses and 139 femoral prostheses, all of modular configuration, retrieved by surgeons in the field, and sent for histologic examination, were analyzed for this study. A number of component characteristics were found to be correlated to early failure. These included acetabular designs with thin polyethylene bearings, poor fixation of the polyethylene to the metal shell, and geometries that permitted a moment to be applied to the bearing insert, tending to cause it to rotate in the metal shell. Modular femoral components were observed to be susceptible to corrosion, with titanium-alloy stems mated to cast cobalt-alloy heads at greatest risk attributable to a galvanic effect. All modular connections of femoral and acetabular components are at risk for disassociation and fretting; therefore, clever design and precision machining are necessary to produce prostheses in which the benefits of modularity exceed the risks.

Acetabulum↗

[Selective sensitivity of cysts to praziquantel and albendazole in a case of cerebral cysticercosis].

A case of neurocysticercosis in a Zaïrian patient with clinical and neuro-radiological follow-up is reported. Treatment with praziquantel resulted in the regression of only some of the cysts. Subsequent treatment with albendazole was effective, eliminating most of the remaining lesions. This case illustrates a selective sensitivity of cysts to praziquantel and albendazole in a single patient.

Adult↗

[Illusion of visual tilt: a case].

A 21-year-old man experienced sudden and intense rotational vertigo. A moment later, he was amazed to see the whole visual world rotate clockwise progressively by about 160 degrees. On the following day, the visual tilt was only 30 degrees, and it soon receded completely, while headache appeared. CT scan, magnetic resonance imaging, vertebral arteriography, and cerebrospinal fluid analysis were normal, and the aetiology could not be ascertained. Illusions of visual tilt are an unusual consequence of disorders affecting the vestibular system. The locus of the impairment is usually in the brainstem, particularly in association with Wallenberg's syndrome. However, the peripheral vestibular pathways or the vestibular projections into the cerebral cortex may occasionally be involved. In the latter case, the visual tilt is part of a vestibular epileptic seizure.

Adult↗

Peripheral facial nerve palsy related to HIV infection: relationship with the immunological status and the HIV staging in Central Africa.

Twelve cases of infranuclear facial nerve palsy associated with infection by the human immunodeficiency virus in the heterosexual African are reported with clinical and immunological studies. Eight cases were healthy HIV carriers, three patients manifested AIDS-related complex and one case fulfilled the CDC criteria for AIDS. Nine patients had a typical Bell's palsy, two presented cephalic Herpes zoster infection with Ramsay Hunt syndrome and one, who suffered from progressive facial weakness, could be considered as having a cephalic form of Guillain-Barré syndrome.

Adult↗

[Seroprevalence of HIV-1 infections in patients consulting the clinic for sexually transmitted diseases in Bangui, Central African Republic].

140 consecutive African, exclusively heterosexual, adult outpatients to the Clinique des Maladies Sexuellement Transmissibles, with genital ulcers or urethritis, were studied in order to determine the status for HIV1-infection and syphilis. Comparison with 194 age and sex matched subjects, without STD, were chosen as controls. In the "STD"'s population, the HIV1 seroprevalence was 17.8%, and anti-treponema antibodies were found in 30% of the cases. Patients with genital ulcer were associated with a higher HIV1 seroprevalence than patients with urethritis. The "STD"'s population in Bangui is at risk for HIV1-infection (risk ratio: 2.12), and constitutes probably a very sensitive group in Central Africa for the epidemiological survey to HIV infection, and for the estimation of the prevention against AIDS.

Adolescent↗

In vitro model of far-field stationary potentials: boundary effects on propagated potentials.

Far-field stationary potentials have been said to result from several factors such as changes in the anatomical orientation of the direction of a propagating nerve action potential (AP) or local modifications of the impedance in the external volume conductor by changes in its geometry or resistivity. In the case of an impedance variation due to the presence of boundaries in the geometry of the medium, the findings reported in this paper showed that it is possible to record simultaneously AP and stationary potentials which we have called boundary potentials (BPs). The BP amplitude depended on the number of active axons at the boundary, on the distance between the boundary and one of the recording electrodes, and on the local impedance variation. Its polarity depended only on the direction of the AP propagation relative to the sign of the local impedance modification, the recording electrodes being in the same relative positions with respect to the direction of the propagating impulse. Finally, the recording of a BP remained possible whatever the relative position of the boundary and of the recording electrodes. These findings are in accordance with some clinical observations not yet explained.

Action Potentials↗