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J Dupouy-Camet

Publications and source records attributed to J Dupouy-Camet.

At least 19 recordsLinked to original sources
PubMed2006

[Diagnosis of Acanthamoeba spp. keratitis with PCR].

AIM: Evaluation of a PCR assay as a diagnostic tool for detection of Acanthamoeba spp. in patients presenting infectious keratitis. METHODS: Between August 2001 and November 2002, 342 clinical specimens consisting in corneal scrapings from 334 patients were tested for Acanthamoeba using direct microscopy, culture, and PCR. A fragment of Acanthamoeba 18S rRNA gene was amplified using a set of primers referred to as Nelson's primers. RESULTS: A diagnosis of Acanthamoeba keratitis was considered for nine patients. Amoeba growth in culture was unfruitful for all of these cases. Eight patients had corneal scrapings that tested positive with PCR; in two cases direct microscopy observations confirmed PCR results. For one patient, a negative PCR result was obtained; however, a second corneal sample and cysts staining on May-Grünwald-Giemsa were positive. A false-positive PCR result was noted related to another amebic genus. A risk factor was found in all Acanthamoeba keratitis cases (contact lenses, trauma). Topical treatment was successful, and keratoplasty was necessary afterwards for optical rehabilitation in five patients. CONCLUSION: This study suggests that PCR is a sensitive diagnostic tool, superior to conventional techniques for detecting Acanthamoeba in corneal lesions.

Acanthamoeba↗
PubMed2006

[First report of a human case of trichinellosis due to Trichinella britovi after jackal (Canis aureus) meat consumption in Algeria].

We report a single case of trichinellosis contracted in Algeria (Batna region), in a practising Moslim. Shortly after returning to France in November 2004, the patient developed the typical clinical and biological signs of the disease. Although the patient claimed having only eaten mutton, an unusual host for Trichinella, a meticulous investigation revealed that he also had eaten a grilled leg of jackal (Canis aureus). One of the four Trichinella larvae detected in a muscular biopsy enabled us to identify the parasite as Trichinella britovi by a multiplex PCR analysis. This is the first identification of the etiological agent of sylvatic trichinellosis occurring in North Africa and the first case of symptomatic trichinellosis due to jackal meat consumption in Africa.

Aged↗
PubMed2005

[Prevalence of Diphyllobothrium latum, L., 1758 infestation in Perca fluviatilis from Lake Leman].

Diphyllobothriasis is contracted by consuming raw or undercooked freshwater fish and is still present on the shores of lake Leman. The aim of this study was to evaluate the prevalence of Diphyllobothrium latum plerocercoid larvae in Perca fluviatilis from this lake. Four to 10% of perch fillets examined in November 2003, February 2004, April 2004 and January 2005, were infested with D. latum larvae. The identification of the larvae was confirmed by PCR and sequencing of the 18S rDNA.

Animals↗
PubMed2005

Human trichinellosis due to Trichinella britovi in southern France after consumption of frozen wild boar meat.

Six patients were infected with Trichinella britovi in southern France following consumption of frozen wild boar meat, which had been frozen at -35 degrees C for 7 days. Microscopic examination of a sample of frozen wild boar muscle revealed the presence of rare encapsulated Trichinella larvae, identified as T. britovi. People eating wild boar must follow individual prophylactic rules such as efficient cooking of meat (at least 65 degrees C at the core for 1 minute) as recommended by the International Commission on Trichinellosis, or freezing exceeding four weeks at -20 degrees C.

Animals↗
PubMed2004

Current situation of human diphyllobothriasis in Europe.

Diphyllobothriasis, a parasitosis caused by the flatworm Diphyllobothrium latum, is contracted by consuming raw or undercooked freshwater fish. The aim of this study was to evaluate the situation of this parasitosis during the past 20 years in Europe through the analysis of databases and search engines (Medline, Cabi Helminthological abstracts,Yahoo, Google), and through a questionnaire sent to a network of European parasitologists and to microbiological laboratories located on the shores of the large Alpine lakes. This study has shown that several dozen cases have been reported each year in Finland and Sweden, that there have been numerous cases in the French or Italian speaking areas of subalpine lakes, and that sporadic cases only have been observed in Austria, Spain, Greece, Romania, Poland and Norway. Over 30 cases have been identified on the Swiss shores of Lake Maggiore since 1990, and 70 cases on the Swiss and French shores of Lake Leman between 1993 and 2002. Eight to 12% of perch fillets from Lake Leman and 7.8 % of perch from Lake Maggiore were infested with larvae. Contamination sources include marinated fish fillets in northern Europe, 'carpaccio di persico' in northern Italy, and perch and charr consumed raw or undercooked around Lake Leman. Factors allowing the continuation of the parasitic cycle include the continued dumping of wastewater into lakes, yachtsmen who also fish, and a possible animal reservoir.

Animals↗
PubMed2004

[New drugs for the treatment of human parasitic protozoa].

Whereas parasitic diseases are always a heavy burden for humanity, few are the new antiparasitic molecules marketed during the last 25 years. Thus on the 1393 new molecules marketed between 1975 and 1999, only 7 have antiprotozoan properties. This talk will detail the progress made in the treatment of the intestinal protozoa, malaria, visceral leishmaniasis and toxoplasmosis, problems with which are especially confronted the European parasitologists. The treatment of Giardia and intestinal amoebas is based on 5-nitro-imidazoles derivatives. Single-dose treatments can be used with tinidazole or secnidazole. Resistance to these compounds of Giardia were described and in these cases, treatment by quinacrine or nitazoxanide are possible alternatives. Nitazoxanide is marketed in the United States and in Australia. It seems to be a well tolerated antiparasitic agent with a broad spectrum because it is active on a lot of intestinal protozoa and helminths. It acts on the same metabolic way as the 5-nitro-imidazoles (inhibition of the ferredoxine reductase) but without synthesis of free radicals and DNA deterioration of the target cell. It is thus neither teratogenic nor mutagenic. Artemisinin derivatives allowed considerable progress in the treatment of malaria. They have short half-lifes, allowing a fast parasitic clearance and these derivatives do no provoke resistance. They are first line drugs for the treatment of malaria in areas of drug resistance. The arthemeter-lumefantrine association (Riamet, Coartem) ensures a rapid disappearance of the circulating parasites and is well tolerated. Atovaquone-proguanil (Malarone) is usable in the treatment of acute malaria but also in disease prevention with the advantage of continuing drug intake for only 7 days after having left the infected area. The treatment of leishmaniasis is always delicate and is characterized by the worrying development of antimony resistances, probably related in the European zones to the treatment of dogs. Liposomal amphotricin is an alternative of choice but remains very expensive. The heating of amphotericin to 70 degrees C during 20 minutes gives it experimental properties and efficacies comparable with that of liposomal amphotericin, but at a less cost. Miltefosine, an alkyl-phospholipide antimetabolite, is very active on visceral leishmaniasis resistant to antimonial treatment. However, its long half-life could induce the emergence of resistances. Miltefosine induces much less side effects than conventional amphotericin B. The commonly used anti-toxoplasmic drugs (sulphadiazine and pyrimethamine) were marketed some 50 years ago and are only active on the rapid forms in multiplication. No drug is really efficient on the cysts although preliminary tests with atovaquone are encouraging to treat ophthalmologic forms in immunocompetent patients. To conclude, it is important to continue to search for new antiprotozoan molecules because, for some parasites, drug resistance is an important problem. Moreover, the treatment of the pregnant women, particularly during the first trimester, is often impossible and there is a lack of galenic forms easily usable in children. A better knowledge of the metabolic pathways of protozoa (particularly the apicoplast of Apicomplexa parasites) would certainly open the posssibility to identify new drugs. To reduce and delay the appearance of resistances, mass-treatments of mass should be avoided and targeted treatments prefered as well as the use of associations of molecules having different modes of action.

Adult↗
PubMed2003

Usefulness of immunoblotting and Goldmann-Witmer coefficient for biological diagnosis of toxoplasmic retinochoroiditis.

Toxoplasmosis is a frequent cause of retinochoroiditis. Although the diagnosis relies mainly on ophthalmological examination, biological approaches are particularly useful in patients with atypical lesions. In a prospective study to determine the value of immunoblotting and immune load calculation in the diagnosis of active toxoplasmic retinochoroiditis, aqueous humor samples from 21 patients with retinochoroiditis and 5 control patients with cataracts were tested. Immune load was calculated on the basis of intraocular antibody production. The immune load ratio between aqueous humor and serum (Goldmann-Witmer coefficient) was significant (i.e. >2) in 9 of the 17 (53%) patients with retrospectively documented toxoplasmic retinochoroiditis. Immunoblotting suggested local antibody production in 10 of 17 (59%) patients. The combination of the two techniques gave a sensitivity of 71% (12/17). Both techniques were negative in the four patients in whom the final diagnosis of toxoplasmic retinochoroiditis was negative and in the five patients with cataracts. These results confirm the value of combining these two techniques. Moreover, immunoblotting has the advantages of being easy to perform and of requiring a very small sample.

Adult↗
PubMed2003

[Ivermectin use in tropical medicine].

Ivermectin is a major breakthrough for the treatment of onchocerciasis, strongyloidosis, scabies and cutaneous larva migrans. Combined with albendazole, ivermectin is highly efficient for treating lymphatic filariasis and intestinal worms. Ivermectin shows very few side-effects but its use in children below 5 and during pregnancy is discussed. Ivermectin tolerance could be related to mdr1 gene expression. Additional studies are needed to assess its efficiency for pediculosis.

Antiparasitic Agents↗
PubMed2001

Evidence for the existence of a proteasome in Toxoplasma gondii: intracellular localization and specific peptidase activities.

The proteasome is a large intracellular protein complex whose main function is proteolytic removal of damaged proteins. It has recently been shown that the proteasome has a crucial role in the pathogenesis of protozoan parasites. We attempted to characterize the proteasome of T. gondii (RH strain). In immunoblot experiments, we showed that MCP231 monoclonal antibody, directed against the human 20S proteasome, labelled homologous proteins in T. gondii with a pattern similar to that observed in mammalian cells. The study of in vitro proteolytic activities showed that chymotrypsin-like activity (the only activity obtained with archaebacteria) was present in Toxoplasma, with Km and specific activity values close to those observed with eukaryotic cells. Immunofluorescence studies showed that the Toxoplasma proteasome predominated in the cytosol.

Animals↗
PubMed2001

Detection of tyrosine phosphorylated proteins in Trichinella spiralis L1 larvae.

Western-blotting analysis showed the presence of tyrosine phosphorylated proteins in crude extracts of T. spiralis larvae and these phosphorylated proteins were located by immunofluorescence on the striations of the larval cuticle. The patterns of phosphorylated proteins were modified when larvae were incubated with bile.

Animals↗
PubMed2001

Trichinella murrelli: pathological features in human muscles at different delays after infection.

The authors describe the pathological aspects of muscles of three patients infected with Trichinella murrelli. Biopsies were carried out at various intervals. Six weeks after infection, the muscular larvae were not encapsulated whereas encapsulation was seen 10 weeks after infection. Six years after infection, the larvae were still alive in a nurse cell surrounded by a very thick capsule. Fourteen years after infection, cuticular larvae remnants were seen in degenerating nurse cells. The late encapsulation of Trichinella murrelli in human muscles could explain some clinical differences noticed during the outbreak during which these three patients were infected.

Adult↗
PubMed2001

[Mitogen activated protein kinases (MAPK) and Toxoplasma gondii host cell invasion].

Toxoplasmosis is still a big concern in Public Health in France, regarding two particular aspects: congenital toxoplasmosis and reactivated toxoplasmosis in immunodeficient patients. Toxoplasma gondii is an obligate intracellular parasite, that can invade almost all nucleated cells. The invasion step has been widely studied, but its accurate mechanism and the cell receptor remain largely unknown. In this work, we have attempted to investigate the role of kinases and signal transduction in the host cell penetration. We characterized mitogen-activated protein kinases (MAPK). in the parasite itself by immunoblotting, immunofluorescence, and determination of enzymatic activity. In particular, we identified two proteins of 43 and 47 kDa, that could be homologues of extracellular signal-regulated kinases (ERK), i.e. ERK2 and ERK1, respectively. These parasite MAPK are activated by calcium and phorbolmyristyl acetate and inhibited by RO 31-8220, suggesting an activation through protein kinases C (PKC). Indeed the MAPK kinase (= MEK) inhibitor PD98059 inhibits the activation of parasite MAPK, suggesting that a MEK homologue could be responsible for the dual phosphorylation of MAPK on tyrosine and threonine residues, necessary for their activation. Finally, we demonstrated that activation or inhibition of parasite MAPK by preincubation of parasites with various activators or inhibitors led to an increased or reduced host cell invasion in vitro by parasites, respectively. All these results are in favour of a role of ERK-type parasite kinases in T. gondii infectivity in vitro.

Animals↗
PubMed2000

Trichinellosis: a worldwide zoonosis.

Trichinella spp. are some of the most widespread parasites infecting people and other mammals all over the world, regardless of climate. This paper attempts to describe the present status of trichinellosis worldwide and to determine if and why trichinellosis is emerging or re-emerging. The global prevalence of the disease is difficult to evaluate but as many as 11 million people may be infected. More than 10000 cases of human trichinellosis were reported by the International Commission on Trichinellosis from 1995 to June 1997 and about 10000 porcine infections were reported by the Office International des Epizooties in 1998. The disease is particularly worrisome in the Balkans, Russia, the Baltic republics, in some parts of China and Argentina. Horsemeat-related outbreaks have been reported in France and Italy and have involved about 3000 patients in the past 25 years. The emergence of trichinellosis in some countries is explained by a better knowledge of the disease (formerly often misdiagnosed as influenza), modifications of consumer habits, re-forestation in Europe and increase of wild game, importation of meats from countries where trichinellosis is endemic and failure of veterinary control due to human error or to social upheavals. This disease linked to meat-consumption which is theoretically easy to prevent by adequate cooking, freezing and veterinary controls, should deserve the attention of all persons involved in public health and it could be eradicated at least from domestic pigs.

Animals↗