Biomedical subjects
Publications and source records attributed to P Brasseur.
The hemolytic activity of an isolate of Monocercomonas spp. from Tropidophis melanurus (snake: Boidae) was investigated. The isolate was tested against human erythrocytes of groups A, B, AB and O and against erythrocytes of six adult animals of different species (rabbit, rat, chicken, horse, bovine, and sheep). Results show that Monocercomonas spp. exerted an hemolytic activity against all erythrocytes tested.
Explore the source record for details and available documents.
A fluctuant, painful, subcutaneous, and intermuscular tumor developed in a 38-year-old man with severe acquired immunodeficiency syndrome (AIDS) in which immunodeficiency was severe. Surgery revealed lesions that formed a multilocular pouch embedded in deep tissues in the forearm filled with tapiocalike material containing a viscous fluid, granules, and cysticercilike small vesicles. Pathologic and parasitologic evaluation showed cysticerci embedded in a fibrocollagen reaction with inflammatory granulomatous reaction. Each cysticercus contained an invaginated scolex with two rows of small (i.e., 80 microm) and large (i.e., 114 microm) rostellar hooks, identical to larva of Taenia crassiceps. All clinical, parasitologic, and pathologic features of these cysticerci were very different from those of all other larval cestode (i.e., Taenia solium cysticercosis, coenurosis, sparganosis, cysticercosis due to Taenia saginata [Cysticercus bovis], primary and secondary hydatidosis [Echinococcus species]). T crassiceps cysticerci usually develop in subcutis and pleuroperitoneal cavities of rodents, whereas the adult tapeworm is commonly found in the digestive tract of foxes. Biologic properties of T crassiceps cysticerci and epidemiologic characteristics of pandemic human immunodeficiency virus (HIV) could eventually indicate new potential cases of T crassiceps cysticercosis in humans.
The susceptibilities of three bovine and two human Babesia divergens isolates to antimicrobial agents were evaluated in vitro by a tritiated hypoxanthine incorporation assay. The MICs at which 50% of isolates are inhibited (MIC50s) for mefloquine (chlorhydrate), chloroquine (sulfate), quinine (chlorhydrate), clindamycin (phosphate), pentamidine (isethionate), phenamidine (isethionate) plus oxomemazine (chlorhydrate), lincomycin (chlorhydrate monohydrate), and imidocarb (dipropionate) were determined. Except for imidocarb, the MIC50s observed for the different isolates were close. Imidocarb and the combination of phenamidine plus oxomemazine exhibited the highest in vitro activity, while antimalarial agents such as mefloquine, choroquine, and quinine were inactive. Other drugs had intermediate activities. The data support further in vitro evaluation of antimicrobial agents active against B. divergens for the improvement of therapeutic strategies.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Water-borne transmission of the coccidium Cryptosporidium parvum Tyzzer, 1912 is frequently responsible for outbreaks of human cryptosporidiosis. One of the most important was reported in 1993 in Milwaukee in the United States, where 403,000 cases were recorded. The determination of the percentage of oocysts excystated is the first step in evaluating their viability, but it alone is not sufficient. This percentage depended on the conditions of storage and also the presence of oxidant or disinfectent agents in water. The percentage of excystation is not always related to viability. Therefore, determination of the viability of excysted sporozoites by determining their infectivity for enterocytic Caco2 cell lines in culture provides information essential for evaluating the risk of contaminated drinking water.
Cryptococcosis is a cosmopolite mycosis caused by an opportunistic fungus usually infecting immunodeficient subjects. A 50-year old patient, with no particular medical history was seen with metaphyseal and diaphyseal bony lesions of a non-specific lytic aspect. This demonstrates that such an infection may also occur in apparently immunocompetent subjects. Diagnosis may be difficult and needs a special investigation looking for Cryptococcus neoformans. It should perhaps be made when first-intention investigations of a lytic bony lesion does not reveal any precise aetiology.
Human babesiosis is a rare parasitic infection caused by an haemoprotozoan of genus Babesia, transmitted by tick bites. In Europe, the most severe cases are observed in asplenic patients infected by Babesia divergens. Acute intravascular haemolytic syndrome appears rapidly and is responsible for renal failure and is life threatening. Most of the cases have been reported in France. In contrast, Babesia microti babesiosis observed in the United States are less severe than Babesia divergens cases. The major problem raised by babesiosis is the rapidity of the clinical and biological diagnosis. The currently recommended treatment of severe cases consists of a blood exchange followed by clindamycine intraveine use, 25 mg/kg/d in three treatments, until disappearance of parasitemia. Prophylaxis against tick bites should be recommended for asplenic individuals.
In 1994, ASBL Namur-Entraide-Sida has been involved in a survey through questionnaires for teachers of the whole high schools in Namur (Belgium). Its purpose was to better notice what sort of viewpoints and modalities in preventing youngs from aids were developed or not during the school. From 2,435 questionnaires, 617 (25%) have been returned and analysed. Among the main results, the teachers' feeling was the professional training is adapted enough in order to response to this item in school and they also hope to improve the efficiency of the inside and outside collaborations. This survey has pointed out the teachers' prime perception of the risks for the pupils to be infected and that, in relation with their own exposition level. This last result leads us to wonder about the indicators which from the prevention from aids has been developed among the school children since the ten latest years. It has not to be forgotten that the urgency of the events is able to hide the stakes of the educative relation and ethic about the teenagers' prevention.
BACKGROUND: Opinion and policy over the use of amodiaquine for treating malaria vary. Amodiaquine is more palatable than chloroquine and may be more effective but serious adverse events have been reported in travellers taking it as prophylaxis. It is not recommended as first-line treatment. In the light of the global debate over the use of this drug, we conducted a systematic review of the effectiveness and tolerability of amodiaquine in the treatment of uncomplicated falciparum malaria. METHODS: This is a systematic review of published and unpublished randomised or pseudorandomised trials of amodiaquine. Observational reports were also systematically identified and reviewed to access evidence of serious adverse events. FINDINGS: 40 trials met the inclusion criteria. Symptomatic patients were enrolled in 24 studies in comparisons of amodiaquine (n = 1071) with chloroquine (n = 1097). Amodiaquine was significantly more effective than chloroquine, with odds ratios and 99% confidence intervals (OR [99% CI]) of 4.29 (3.30-5.58) on day 7 and 6.00 (3.97-9.06) on day 14. Time to parasite clearance was significantly shorter with amodiaquine and fever clearance times were marginally faster. Eight studies compared amodiaquine with chloroquine in asymptomatic parasitaemia, with effects on parasitological outcomes similar to those for symptomatic malaria. At twelve sites, 692 amodiaquine and 679 sulfadoxine/pyrimethamine (S/P) recipients were enrolled. The two drugs did not differ significantly on day 7 (OR 0.74 [0.48-1.15]) but the odds ratios favoured S/P on day 14 (OR 0.51 [0.28-0.93]) and on day 28 (OR 0.30 [0.16-0.55]). The time to parasitological clearance was similar in the two groups; fever clearance times were significantly shorter with amodiaquine. Tolerability was assessed for both comparative and non-comparative trials. The rates of adverse events in controlled trials were 10.7%, 8.8%, and 14.3% with amodiaquine, chloroquine, and S/P, respectively. No life-threatening adverse events and no significant shifts in laboratory indices were reported. INTERPRETATION: This systematic review of published and unpublished trials supports the use of amodiaquine in the treatment of uncomplicated malaria. However, there is partial cross-resistance between chloroquine and amodiaquine, and monitoring of the effectiveness of this drug and surveillance for evidence of toxicity must continue.
Sera from subjects vaccinated with the Pasteur Merieux (PM) inactivated hepatitis A vaccine (AVAXIM) have been analysed in order: (1) to assess comparability of the results provided by a modified radio-immunoassay (mRIA) in the different laboratories involved in testings of sera during clinical trials and by enzyme-linked immunoabsorbent assay (ELISA) used during development of other inactivated hepatitis A vaccines; (2) to describe the IgM responses elicited by this vaccine compared with one control vaccine [HAVRIX, 720 ELISA antigens units; Smithkline Beecham (SB), Rixensart, Belgium]; (3) to provide comparative data between the PM vaccine and the SB vaccine on neutralizing activities of vaccine-induced antibodies. Vaccine-induced antibody titres evaluated by a mRIA in different laboratories correlated well and validated the comparability of the results obtained in various vaccine trials conducted by PM. Geometric mean titres (GMTs) expressed as milli-international units (mlU/ml) were higher with ELISA especially after the first dose, but seroconversion rates were similar and a good correlation was found between the two assays. IgM vaccine-induced antibodies were detectable in nearly all vaccinated subjects from week 2 after vaccination, with a peak titre between weeks 2 and 4 after the first dose. Comparison of GMTs by the Student Fisher t-test was statistically significant (P < 0.05) only at week 2 with higher titres in PM vaccinees. Neutralizing antibodies were detected after vaccination with the PM inactivated hepatitis A vaccine. The titres gradually increased between the second week after the first dose and the booster dose (week 24). A strong booster effect of the second dose on neutralizing titres was observed. Seroneutralizing titres induced at week 2 in subjects vaccinated with the PM inactivated hepatitis A vaccine were statistically significantly higher (P < 0.05) from those induced by the SB vaccine.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Rats immunosuppressed by hydrocortisone acetate and a low protein diet were challenged with Cryptosporidium Parvum oocysts and studied on days 10, 35 and 70 post-infection. The biliary tract was found to be a major site of parasite infection. C. parvum was visible in the biliary papillary area in association with a proliferation of highly convoluted tubular glands. The papillary lumen was narrowed, and an upstream dilation with bacterial proliferation was seen. The liver was initially free of lesions, and subsequently exhibited late lesions of cholestasis. Parasites were not found in the pancreatic duct, although pancreatitis was frequently observed. Oocysts were consistently present in the distal portion of the ileum. Both challenged and unchallenged immunosuppressed rats, exhibited widespread focal hepatic infarcts and pyelonephritis. Other organs appeared free of lesions. In addition to the intestine, data identified the biliary tract as a major site of C. parvum infection and as a potential protected reservoir which may sustain a chronic infection.
The tick transmission of Babesia from infected animals to human has been clearly demonstrated. Including the first case described by Skaraballo in 1957 in Yugoslavia, 22 cases of human babesiosis have been reported in Europe. B. divergens, which is the most common pathogen for cattle, was involved in 17/22 cases. France, British Isles and Ireland accounted for more than half of the cases, occurring especially between May and October, the period of maximal activity of Ixodes ricinus, considered as the major vector. Splenectomy was the main factor of risk which was found in 86% of the patients. Clinically, babesial infections appeared suddenly with a non periodic high fever, shaking chills, sweat, headache, myalgia and jaundice induced by intravascular hemolysis. The mortality rate was higher than 50%. Treatment should be promptly initiated with a massive blood exchange, followed by intravenous clindamycin (600 mg) three time daily. For prophylaxis, attenuated vaccines could provide effective protection in cattle, but no vaccine is available for human protection.
A reversed-phase high-performance liquid chromatographic method for the determination of sinefungin, a new antiprotozoal drug, in rat plasma has been developed and validated. Sample preparation was performed at 4 degrees C by deproteinization with acetonitrile. Vidarabine was used as an internal standard. Both sinefungin and vidarabine were separated on a C18 column with a mobile phase of ammonium dihydrogenphosphate-acetonitrile (95:5, v/v) and detected by ultraviolet absorbance at 260 nm. Recoveries of sinefungin from plasma were 75 +/- 3.2% and 81 +/- 4.8% following dosage at concentrations of 10 micrograms/ml and 30 micrograms/ml, respectively. Using 250 microliters of rat plasma, the limit of quantitation was 1 microgram/ml sinefungin, and the assay was linear from 1 to 30 micrograms/ml. This method appears sensitive enough to be used in further pharmacokinetic studies of sinefungin in animal models.
A formalin-inactivated aluminium hydroxide adsorbed hepatitis A vaccine was evaluated in a dose-response study on 195 healthy male adults (age range: 18-31 years) in two French hospitals (Lyon, Rouen). Four doses (20, 40, 80, 160 RIA antigen units) were administered intramuscularly (i.m.) in two injections over a 6-month period. At the time of the first vaccine injection, 32 subjects (16.4%) were found positive (> 20 mIU ml-1) for HAV antibody (total Ig RIA HAVAB assay, Abbott Laboratories) and were excluded from the analysis of immunogenicity criteria. Fourteen days after the first vaccine injection, 78.1% (95% confidence interval (CI): 62-90) of seronegative subjects who received the 160 RIA antigen unit dose seroconverted with a geometric mean titre (GMT) of 43 mIU ml-1 (95% CI: 33-56). Seroconversion was 100% (95% CI: 91-100) at 1 month with a GMT of 95 mIU ml-1 (95% CI: 79-112). Statistical analysis revealed a significant dose-related effect (p < 0.0001) on GMT by multivariate regression analysis of the results after the first injection. Biological safety was evaluated and alanine aminotransferase and aspartate aminotransferase levels were similar prior to and 14 days after the first injection in the four groups. Reactions after injection were similar in the four dosage groups: 6.2% of subjects reported immediate reactions after first vaccination (feeling sick, spontaneous pain, headache), 8.9% reported local reactions at the site of injection (spontaneous pain, haematoma, local adenopathy) and 13.5% reported general reactions ('flu-like' syndrome, gastrointestinal tract disorders, fatigue, headache).(ABSTRACT TRUNCATED AT 250 WORDS)