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D A Vuitton

Publications and source records attributed to D A Vuitton.

97 records · Page 6Linked to original sources
PubMedDate not supplied

Analysis of immunoglobulin G subclass in the serum antibody responses of alveolar echinococcosis patients after surgical treatment and chemotherapy as an aid to assessing the outcome.

Immunoglobulin G (IgG) subclass-specific antibody responses were evaluated for the follow-up of alveolar echinococcosis (AE) patients. Seventy-four sequentially collected sera from 25 Chinese and French AE cases who underwent surgery including hepatectomy, liver transplant and/or chemotherapy were analysed quantitatively and qualitatively during the clinical follow-up period. These AE patients were classified in 4 groups--cured, improved, stabilized, or aggravated. Serum antibody levels of the subclasses IgG1 and IgG4 were significantly higher in the AE patients than in healthy controls. IgG1 and IgG4 isotypes in AE patients were the most sensitive IgG antibody response in an enzyme-linked immunosorbent assay (ELISA) and in binding to antigens of 44kDa, 35kDa, 21kDa and 17.5kDa in an Echinococcus multilocularis protoscolex extract after Western blotting. In AE cases classed as cured or improved, IgG subclass antibody levels tended to decrease earlier than total IgG levels, especially IgG4 antibody levels which became negative within one year after successful treatment. IgG4 antibody levels also decreased in most of the improved cases. Increasing or unchanged levels of IgG4 and IgG1 antibodies were demonstrated in both stabilized and aggravated AE cases using both ELISA and immunoblot assays. Reappearance of specific IgG4 antibodies was a strong indication of recurrence, especially in liver transplant patients. Combined quantitative and qualitative assessment of IgG1 and IgG4 antibodies may be potentially useful for the serological follow-up of human AE.

Adult↗
PubMedDate not supplied

Cystic echinococcosis in semi-nomadic pastoral communities in north-west China.

In order to determine the prevalence of human cystic echinococcosis (CE) in semi-nomadic traditional pastoralist groups in north-west China, 2 large community studies were undertaken in Altai and Tacheng Prefectures in 1990/91 and 1995/96, respectively. The Kekergash community (Altai) comprised mainly ethnic Kazakhs, whereas the Narenhebuke community (Tacheng) comprised mainly Mongolians. Populations were screened for CE by abdominal ultrasound scan (US) and serological tests. The total prevalence of confirmed human CE was higher in Narenhebuke (2.7%, 49/1844) than in Kekergash (0.9%, 17/1861; P < 0.01). Within each community there was no significant difference of CE prevalence between the Kazakh and Mongolian groups, although Han Chinese exhibited twice the rate of CE (4.9%) in Narenhebuke compared to the dominant Mongolian population. For each community, human CE prevalence increased with age and there was a greater risk associated with the practice of home slaughter of livestock. Dogs were screened for Echinococcus granulosus infection and re-infection levels using a highly specific coproantigen test. The proportion of dogs with positive coproantigen tests was significantly higher in Narenhebuke (36.0%, 50/139) compared to Kekergash (17.8%, 16/90). In Narenhebuke the re-infection levels of dogs, as determined by coproantigen positivity, were higher in the winter quarters (49.4%, 39/79) compared to the summer quarters (18.3%, 11/60; P < 0.01). Furthermore, coproantigen re-test positivity was 25% at 3 months and 29.2% at 7 months. Highest dog coproantigen positivity was obtained over the winter period.

Adolescent↗
PubMedDate not supplied

Combined eco-epidemiological and molecular biology approaches to assess Echinococcus granulosus transmission to humans in Mauritania: occurrence of the 'camel' strain and human cystic echinococcosis.

Mauritania lies between West-Central Africa where human cystic echinococcosis (CE) is considered extremely rare and West Maghreb where CE accounts for a real public health problem. Until 1992, Mauritania was considered as human CE-free even through CE seemed well known in livestock. In 1992, the introduction of ultrasonography led to the diagnosis of the first human CE cases. In 1997, a veterinary study revealed that dogs living around Nouakchott were commonly infected by Echinococcus granulosus. To assess E. granulosus transmission and to identify the most relevant animal reservoir responsible for human CE emerging in Mauritania, a simultaneous eco-epidemiological and molecular biology approach was performed. The fieldwork included sample collection and investigation of relationship between intermediate hosts, definitive hosts and humans. Typing of E. granulosus strains was performed using comparison of polymerase chain reaction (PCR)-amplified DNA sequences with one nuclear (BG 1/3) and 2 mitochondrial (COI, NDI) targets. Results show that the 'camel' strain is actually infectious to humans and circulates between intermediate hosts including camels and cattle. It is suggested that preventive measures at slaughtering places could reduce human contamination.

Animals↗
PubMedDate not supplied

Classification, follow-up and recurrence of hepatic cystic echinococcosis using ultrasound images.

Ultrasound image and morphological structure of hepatic cystic echinococcosis (CE) were analysed in 277 human cases (385 hepatic hydatid cysts). These included 65 CE cases from community surveys carried out between 1995 and 2000 in 3 countries (China, Mongolia and Jordan) and 212 cases from a clinical hospital survey from Xinjiang, China. A new simplified WHO ultrasound classification for human CE was assessed, and considered useful. It is proposed that type, size and number in particular need to be included in the ultrasound classification of hepatic CE. For comparative purposes 6 categories of type were classified in the study as Type 0 to Type 5 (T0-T5): T0, univesicular without pathognomonic signs; T1, univesicular with pathognomonic signs; T2, cysts with sagging or floating laminated membrane; T3, cysts containing daughter cysts; T4, solid mass or mixed cysts; and T5, cysts with partial or full calcifications. This differs from the WHO classification wherein Type T3 cysts (daughter cysts present) are considered a pathological stage to occur in general prior to the sagging or floating membrane (T2) stage. Recurrent hydatid cysts in the liver were also studied based on morphological structures observed directly from surgical intervention. Case follow-up over 1-5 years since endocystectomy in the community surveys indicated 10% (2/10) recurrence of cysts in the residual surgical cavity. Recurrent CE included 2 (2/4) cases after percutaneous treatment.

China↗
PubMedDate not supplied

Soluble IL-2-receptor and CD8 in the serum and the periparasitic granuloma of patients with alveolar echinococcosis.

Cellular immunity plays a key role in the defence against the larva of the cestode Echinococcus multilocularis. This larva is responsible for alveolar echinococcosis (AE) of the liver, a rare parasitic disease which occurs in endemic areas including European alpine countries, Alaska, the USSR, Western China and Northern Japan. We have shown a marked decrease of the CD8+ T-cell population in the blood and we have described an infiltrate composed mainly of activated CD8+ T-cells in the liver lesions of most patients with AE. In this study, we assessed the serum level of soluble IL-2-receptor (sIL-2R) and CD8 (sCD8) in 37 patients (23 men, 14 women, mean age 59.5 yrs) with a histologically proven AE. The results, obtained using sandwich ELISA, were compared to those of healthy controls and correlated to parameters evaluating the severity of the disease. The mean serum levels of sIL-2R were significantly higher in AE patients than in controls. There was a significant correlation between sIL-2R levels and both the volume of parasitic lesions and a calculated index of severity of the disease. The mean serum levels of sCD8 did not differ significantly from the values obtained in controls. These results indicate that the infiltration of the liver by CD8+ T-lymphocytes is not associated with an increased release of sCD8 into the serum. The circulating levels of sIL-2R appear to reflect the extent as well as the severity of the disease. Immunostaining of the cells of the periparasitic granuloma suggests that the cell origin of the sIL-2R could be macrophages rather than T-lymphocytes.

Adult↗
PubMedDate not supplied

Cellular localisations of interleukin-1 beta, interleukin-6 and tumor necrosis factor-alpha mRNA in a parasitic granulomatous disease of the liver, alveolar echinococcosis.

Alveolar echinococcosis (AE), an uncommon and very severe parasitic liver disease, can be considered as an "infectious model" of granulomatous disease, where cellular immunity plays a key role in the defence against Echinococcus multilocularis, the larval cestode responsible for the disease. We analysed the localisation of the expression of the pro-inflammatory cytokines IL-1 beta, IL-6 and TNF-alpha mRNA in human AE liver lesions, in the periparasitic granulomas and in the hepatic parenchyma, as well as the phenotypic characteristics of the cells on serial sections. In situ hybridizations, using anti-sense 35S dUTP-labeled IL-1 beta, IL-6 and TNF-alpha riboprobes, were performed on cryostat liver sections; the sense probes were used as negative controls. IL-1 beta, IL-6 and TNF-alpha mRNA were observed in macrophages located at the extreme periphery of the granuloma, between the lymphocytic ring and the liver parenchyma, in patients with active AE. No cytokine mRNA expression was observed in a patient with an abortive case. Only TNF-alpha mRNA was located in the periparasitic area, in cells morphologically identified as macrophages but exhibiting an unusual phenotype (CD 11b-, CD 25+); this particular expression was observed only in those patients with very fertile lesions, associated with centro-granulomatous necrosis. These results show that pro-inflammatory cytokines are consistently produced by macrophages at the periphery of the periparasitic granuloma and can serve as mediators of acute-phase protein secretion and of fibrogenesis in that location.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗