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B Bouteille

Publications and source records attributed to B Bouteille.

At least 37 records · Page 2Linked to original sources
PubMed2000

Monoclonal antibodies to Hammondia hammondi allowing immunological differentiation from Toxoplasma gondii.

Five murine monoclonal antibodies (MAbs) were developed against purified sporozoites of Hammondia hammondi. Despite a large antigenic similarity between the 2 closely related coccidia, H. hammondi and Toxoplasma gondii, these MAbs only reacted with H. hammondi. Three MAbs, ID3, 3F2, and 4C9-7, recognized antigens of 38 kDa localized in rhoptries (1D3), in rhoptries and in oocyst and cyst walls (3F2), and in rhoptries and the apical region (4C9-7). Another MAb, 4C9-10, reacted with a 27-kDa antigen in dense granules of sporozoites and tachyzoites, and MAB 11B3 labeled an antigen of >94 kDa located in the pellicular membrane of the 3 stages of the parasite. These MAbs could be used for a rapid discrimination of the 2 coccidia in epidemiological studies or for diagnostic purposes in tissues.

Animals↗
PubMed2000

[Cysticercosis and epilepsy in the city of Tone, north of Togo].

An epidemiology study was conducted in Tone, a city in the very north of Togo from November 1 to 25, 1995. The prevalence of epilepsy was studied in 9,155 subjects and seroprevalence of cysticercosis in 1,343. This was a representative sample of this region with 194,000 inhabitants. The prevalence of epilepsy was 18.6 per 1 000 inhabitants. A causal relationship was found betwen cysticercosis and epilepsy. The prevalenced of cysticercosis was 38 per 1 000 persons in the general population and 135.29 per 1 000 epileptic patients. The difference was highly statistically significant (X( 2)=74.17, p<10(-6)).

Adult↗
PubMed1999

Onchocerciasis and epilepsy: a matched case-control study in the Central African Republic.

The occurrence of epileptic seizures during onchocercal infestation has been suspected. Epidemiologic studies are necessary to confirm the relation between onchocerciasis and epilepsy. A matched case-control study was conducted in dispensaries of three northwestern towns of the Central African Republic. Each epileptic case was matched against two nonepileptic controls on the six criteria of sex, age (+/-5 years), residence, treatment with ivermectin, date of last ivermectin dose, and the number of ivermectin doses. Onchocerciasis was defined as at least one microfilaria observed in iliac crest skin snip biopsy. A total of 561 subjects (187 cases and 374 controls) were included in the study. Of the epileptics, 39.6% had onchocerciasis, as did 35.8% of the controls. The mean dermal microfilarial load was 26 microfilariae per mg of skin (standard deviation, 42) in the epileptics and 24 microfilariae per mg of skin (standard deviation, 48) in the controls. This matched case-control study found some relation (odds ratio = 1.21, 95% confidence interval 0.81-1.80), although it was nonstatistically significant.

Adolescent↗
PubMed1999

Sedimentation field-flow fractionation application to Toxoplasma gondii separation and purification.

Toxoplasmosis is a worldwide disease caused by Toxoplasma gondii, an intracellular protozoa of micronic size range (4-10 microm). Its classical purification processes are complex and often associated with low recovery. All investigation procedures concerning this parasite require its isolation and purification from at least the mouse ascitic fluid. For this purpose, a recently developed laboratory technology was used, i.e. sedimentation field-flow fractionation. This chromatographic-like separation technology was demonstrated to be particularly selective for isolation and separation of micron-sized biological particles. Sedimentation field-flow fractionation operated on the steric-hyperlayer mode was used to isolate the parasite from the remanent ascitic contaminants of different origins and from red blood cells. With this technology, 86% recovery with 97% viability was obtained in less than 30 min.

Animals↗
PubMed1999

Pharmacokinetics, metabolism and excretion of megazol, a new potent trypanocidal drug in animals.

The pharmacokinetics of megazol (CAS 19622-55-0) was investigated after intraperitoneal and oral administration of the drug (80 mg/kg) to mice. The plasma levels were significantly higher after oral administration of drug than after intraperitoneal route (33.8 micrograms/ml compared with 19.0 micrograms/ml for Cmax, 158714 micrograms.h/l compared with 96057 micrograms.h/l for AUC). When suramin (CAS 145-63-1) was administered 24 h before oral administration of megazol, megazol absorption was accelerated (2 h compared with 4 h for Tmax) but the amount absorbed was lower (19.9 micrograms/ml compared with 33.8 micrograms/ml for Cmax and 95547 micrograms.h/l vs 158714 micrograms.h/l for AUC). In the infected mice previously treated with suramin, all estimated pharmacokinetic parameters of plasma megazol were significantly modified, in particularly an increase in the apparent volume of distribution (5.6 l/kg compared with 0.9 l/kg) with a prolongation of the elimination half-life (3 h compared with 0.7 h) of megazol. Excretion of the total radioactivity of megazol was also evaluated after oral administration of 3H-megazol to rats. Total radioactivity was eliminated predominantly via the urinary route (80%) vs. 10.5% in the faeces, 9.5% remaining in the body 8 days after dosing. When unlabelled megazol was orally administered to rats with absence or presence of suramin, megazol recovered in urine and faeces 72 h dosing was: 55.7%/2% vs 20.6%/1.6%, respectively. In the urine, unchanged megazol was present as characterized by LC-MS/MS as well as 4 unknown metabolites. This study indicates that suramin significantly affects the pharmacokinetics of megazol and its elimination.

Administration, Oral↗
PubMed1999

[Cerebral miliary granulomatosis with Histoplasma capsulatum in an HIV seronegative patient].

A 51 year old patient who worked in Africa for eight years, presented twelve years later a progressive ataxia associated with headaches. Neuroimaging studies done after a partial complex seizure demonstrated multiple supra and sub-tentorial cortical ring enhancing lesions. Histoplasma capsulatum histoplasmosis was found on histological examination of brain biopsy and confirmed by isolation of the fungus. Medical treatment with intravenous amphotericin B followed by oral itraconazole (400 mg per day) improved both clinical and radiological status. This observation of cerebral histoplasmosis is rather unusual for a seronegative HIV patient in a non endemic area.

Amphotericin B↗
PubMed1999

Hammondia hammondi organelle proteins are recognized by monoclonal antibodies directed against organelles of Toxoplasma gondii.

Hammondia hammondi and Toxoplasma gondii, 2 closely related coccidia of cats, are known to share many antigenic molecules as shown by serologic cross reactivity. Monoclonal antibodies (MAbs) directed against the internal organelles of Toxoplasma gondii were tested by immunofluorescence assay and immunoelectron microscopy on the tachyzoites of H. hammondi. The MAbs anti-apex, anti-dense granules, anti-micronemes, and anti-rhoptries recognized, although weakly, the corresponding antigens on H. hammondi. This finding demonstrates that organelles of the 2 parasites are not only morphologically, but also antigenically, similar.

Animals↗
PubMed1999

[Epidemiological observations on the first case of human paragonimiasis and potential intermediate hosts of Paragonimus sp. in Benin].

Parasitological investigations were carried out for four months in 1998 in two Beninese centres of pneumo-phtisiology (Akpakpa, at Cotonou, and Akron, at Porto-Novo) to detect the patients harbouring eggs of Paragonimus sp. amongst the persons consulting for tuberculosis and showing a broncho-pneumopathy without mycobacteria. Eggs of Paragonimus sp. were detected in the sputum of a single patient out of 369 persons examined (prevalence, 0.2%). This patient had eaten crabs in the months preceding the date of diagnosis. A treatment using praziquantel has improved clinical symptomatology and biological signs found in this patient. These studies have been completed by visiting markets located in the coastal plain of Benin to identify the crabs that were sold and to find metacercariae of Paragonimus sp. Negative results were obtained when 126 Cardisoma armatum ("hole crab") were dissected. In contrast, the dissection of 176 Callinectes marginatus ("swimming crab") was successful, with 5% of crabs harbouring metacercariae of probably Paragonimus sp. Further studies are necessary to confirm these first results and to determine the global prevalence of Paragonimus infection in these definitive and intermediary hosts.

Aged↗
PubMed1998

Megazol combined with suramin: a chemotherapy regimen which reversed the CNS pathology in a model of human African trypanosomiasis in mice.

Chemotherapy for human African trypanosomiasis (HAT), or sleeping sickness, is unreliable because of resistance, refraction and toxic and adverse side-effects. Using a long-term experimental model of HAT with involvement of the central nervous system (CNS), we tested the ability of a megazol and suramin combination treatment to eliminate CNS trypanosomes. This consisted of 20 mg suramin per kg body weight administered intraperitoneally (i.p.), followed 24 h later by 4 daily doses (80 mg/kg) of megazol given either i.p. or per os. One week post-treatment, neurological disorders had disappeared. One of 15 mice relapsed in each application group at 81 and 98 days after treatment, respectively. At six months, no signs of relapse were seen in remaining mice, indicating that this chemotherapy regimen was curative. Immunohistochemical (astrocytosis) and histological (inflammatory lesions) examinations of brain tissues showed that animals returned to normal from 2 months post-treatment. These results suggest that the megazol-suramin combination reversed the CNS pathology in this model.

Animals↗
PubMed1998

[Human African trypanosomiasis, contributions of experimental models].

Melarsoprol has remained the chosen drug for the late-stage treatment of human African trypanosomiasis (HAT) due both to Trypanosoma brucei (T.b.) gambiense and T.b. rhodesiense; however, arsenical encephalopathies, which are often fatal, occur in 5-10% of the treated cases. To date, two major problems have not been solved. The first one is the precise diagnosis of early involvement of the central nervous system (CNS) which determines the therapeutics to be administered. The second one is linked to the lack of data on in vivo efficacy of products which are effective in vitro against trypanosomes. Answers have to be provided by experimental animal models of HAT. Such models would allow for better studies of the pathology and pathogenesis of the disease, as well as therapeutic trials of potentially effective new drugs or combinations. We have developed acute and chronic murine and sheep experimental animal models of HAT infected by T. b. brucei. Meningoencephalitis and neurological signs are relatively difficult to obtain in murine models and require artificial means, such as suramin treatment on day 21 after-infection. The chronic murine model has demonstrated CNS involvement with meningitis, followed by meningoencephalitis with progressive astrocytosis. The sheep model develops a disease with CNS complications and cerebrospinal fluid can be collected. In the sheep model, we have described anti-galactocerebrosides antibodies, which represent major components of myelin, which may indicate an autoimmune process in the CNS. We then described these antibodies in the cerebrospinal fluids and sera from patients at a late-stage of the disease. From a therapeutic point of view, we have cured mice or sheep with low doses of melarsoprol, or with the nitroimidazole derivatives Ro 15-0216 and megazol, alone or combined with suramin. Further studies of these nitroimidazole compounds, which could be proposed for human use, have to be carried out on a-primate model infected by T.b. gambiense. To our knowledge, this primate model is not available. This is why we have recently developed a T. b. gambiense primate model of HAT on Cercopithecus aethiops.

Animals↗
PubMed1998

Antigenic similarity between Hammondia hammondi and Toxoplasma gondii tachyzoites.

Hammondia hammondi is an obligate heteroxenous intestinal coccidian of cats, sharing many characteristics with Toxoplasma gondii. The tachyzoite stage antigens of T. gondii and H. hammondi were studied by immunofluorescence assays (IFA) and western blotting (WB) techniques to demonstrate antigenic similarities. Five monoclonal antibodies (MAbs), anti-T. gondii antigens, P22, P23, P30, P35, and P43, and mice polyclonal anti-H. hammondi serum were investigated. Antigens of H. hammondi were recognized by anti-P30 MAb both in IFA and in WB and by anti-P22 and anti-P35 MAbs only in IFA. Polyclonal anti-H. hammondi serum revealed many common antigens between the 2 parasites (30, 32, 35, 66, and 90 kDa). The differences of host parasite relationship between these 2 coccidians lead us to suggest that many of these antigens with similar molecular weights are not the same, but homologous, molecules or that they are not the only factors involved in these differences.

Animals↗
PubMed1997

Simple high-performance liquid chromatographic method to analyse megazol in human and rat plasma.

A simple and sensitive high-performance liquid chromatographic method has been developed to measure megazol in human plasma. The method was optimized and validated according to the Washington Concensus Conference on the Validation of Analytical Methods (V.P. Shah et al., Eur. J. Drug Metab. Pharmacokinet., 15 (1991) 249). The criteria of complete validation were specificity, linearity, precision, analytical recovery, dilution and stability. It involved extraction of the plasma with dichloromethane, followed by reversed-phase high-performance liquid chromatography using a Kromasil C8 column and UV detection at 360 nm. The retention times of the internal standard (tinidazol) and megazol were 6.10 and 9.60 min, respectively. The standard curve was linear from 2 ng ml-1 (limit of quantification) to 2000 ng ml-1. The coefficients of variation for all the criteria of validation were less than 6%; 85 to 92% extraction efficiencies were obtained. Megazol was stable during the storage period (one month at -20 degrees C) in plasma and for two months at 25 degrees C in standard solution. The method was tested by measuring the plasma concentration following oral administration to rat and was shown to be suitable for pharmacokinetic studies.

Animals↗
PubMed1997

Trypanosoma brucei brucei: a long-term model of human African trypanosomiasis in mice, meningo-encephalitis, astrocytosis, and neurological disorders.

The search for a chronic experimental model for human African trypanosomiasis (HAT) in animals with cerebral lesions and neurological disorders has been difficult. Models with meningo-encephalitis have been proposed using Trypanosoma brucei gambiense or T. b. rhodesiense. Meningo-encephalitis is rare in infection with T. b. brucei. It has been shown that the treatment of mice infected with T. b. brucei with diminazene aceturate (Berenyl) led to development of a rapid meningo-encephalitis. In this study, we report the development of a chronic experimental model of HAT in mice infected with T. b. brucei AnTat 1.1E. To obtain a chronic evolution of the infection, on Day 21 postinfection, mice were treated with a dose of suramin (Moranyl) at 20 mg x kg(-1) body weight, a dose which failed to eliminate trypanosomes in the central nervous system (CNS). This treatment, repeated after each parasitemic relapse in the blood, allowed animals to survive more than 300 days postinfection. After a few weeks of infection, mice displayed neurological signs. Histological studies showed the appearance of increasing inflammatory lesions, from meningitis to meningo-encephalitis, with progression of lesions throughout the perivascular spaces in cerebral and cerebellum parenchyma. No demyelination or neuronal alteration were observed except in the necrotic spaces. Trypanosomes were observed in different structures in CNS. An immunohistochemical study of glial fibrillary acidic protein (GFAP) showed an increasing astrocytosis according to the duration of the infection. This model reproduces neurological and histological pathology observed in the human disease and can be useful for further immunopathological, neurohistological and therapeutic studies on this condition.

Animals↗
PubMed1997

Detection and characterization of autoantibodies directed against neurofilament proteins in human African trypanosomiasis.

In serum and in cerebrospinal fluid (CSF) from patients with human African trypanosomiasis (HAT) with central nervous system involvement, we detected autoantibodies directed to some proteins from these tissues. The characterization of antigenic proteins by Western blotting showed that the antibodies recognized the 200-kD and 160-kD proteins of neurofilament (NF). Serum anti-NF antibodies were more frequent in HAT patients than in control subjects (86% versus 24%; P < 10[-9]) and they belonged predominantly to the IgM class (anti-NF IgM = 86% versus anti-NF IgG = 4%; P < 10[-9]) in the patients with stage II (central nervous system involvement) HAT. The CSF antibodies to NF were IgM in 88% (22 of 25) of the cases and IgG in 32% (8 of 25) of the cases. Epitopes shared by NF and trypanosomes were detected by indirect immunofluorescence and this was confirmed by the disappearance of anti-NF reactivity after adsorption with trypanosome antigens (Trypanosoma brucei brucei or T. b. gambiense). Anti-NF antibodies were undetectable in the CSF from stage I HAT patients.

Animals↗
PubMed1997

[Seroprevalence of cysticercosis, taeniasis and swine infection on Réunion Island in 1992].

Cysticercosis is a parasitic disease commonly observed in developing countries in Latin America, Africa, and Asia. Many cases involving cerebral injury have been reported on Reunion Island, a French department in the Indian Ocean. The present article describes the findings of a seroprevalence survey performed from September 1990 to May 1992 using an ELISA technique. Out of a total of 1010 individuals randomly selected from the voter registration records of the island's 24 polling districts, 993 agreed to be interviewed and undergo blood testing. Samples from 14 individuals were positive for cysticercosis, indicating a seroprevalence of 1.4% with 95% confidence interval from 0.7 to 2.1%. Seropositive individuals were evenly distributed throughout the island with no statistical difference regarding sex and age. A retrospective study showed that diagnosis of taeniasis was uncommon (less than 0.02% of stool examinations for parasites). Meat inspection records showed that no pork had be seized due to taeniasis since 1993 but raising of pigs by private citizens without veterinarian control is still widespread. Living conditions are improving and eradication of endemic cysticercosis seems achievable by enforcing zoning codes and educating people about the need for proper meat handling and treatment of taeniasis.

Adult↗