226 resultados para Schistosomiasis mansoni


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The Th1/Th2 balance represents an important factor in the pathogenesis of renal ischemia-reperfusion injury (IRI). In addition, IRI causes a systemic inflammation that can affect other tissues, such as the lungs. To investigate the ability of renal IRI to modulate pulmonary function in a specific model of allergic inflammation, C57Bl/6 mice were immunized with ovalbumin/albumen on days 0 and 7 and challenged with an ovalbumin (OA) aerosol on days 14 and 21. After 24 h of the second antigen challenge, the animals were subjected to 45 minutes of ischemia. After 24 h of reperfusion, the bronchoalveolar lavage (BAL) fluid, blood and lung tissue were collected for analysis. Serum creatinine levels increased in both allergic and non-immunized animals subjected to IRI. However, BAL analysis showed a reduction in the total cells (46%) and neutrophils (58%) compared with control allergic animals not submitted to IRI. In addition, OA challenge induced the phosphorylation of ERK and Akt and the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in lung homogenates. After renal IRI, the phosphorylation of ERK and expression of COX-2 and iNOS were markedly reduced; however, there was no difference in the phosphorylation of Akt between sham and ischemic OA-challenged animals. Mucus production was also reduced in allergic mice after renal IRI. IL-4, IL-5 and IL-13 were markedly down-regulated in immunized/challenged mice subjected to IRI. These results suggest that renal IRI can modulate lung allergic inflammation, probably by altering the Th1/Th2 balance and, at least in part, by changing cellular signal transduction factors. Copyright (C) 2012 S. Karger AG, Basel

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Solanum lycocarpum (Solanaceae), a Brazilian medicinal plant known as "wolf fruit," contains about 1.5% of glycoalkaloids in its dried fruits, consisting mainly of solamargine and solasonine. The present work reports the obtainment of the alkaloidic extract of the S. lycocarpum fruit by acid-base extraction and the isolation of the major alkaloid heterosides by chromatographic means, as well as the evaluation of their in vitro schistosomicidal activities. The in vitro schistosomicidal activities of the alkaloidic extract of S. lycocarpum fruits and its isolated steroidal alkaloids were undertaken against adult worms of Schistosoma mansoni. The alkaloidic extract (20, 32, and 50 mu g mL(-1)), solasonine (50 mu M), solamargine (32 and 50 mu M), and equimolar mixture of glycoalkaloids (20, 32, and 50 mu M) lead to the separation of all couple worms and extensive disruption on their teguments, such as sloughing, as well as their deaths within 24 h of incubation. In addition, the alkaloidic extract (10 and 15 mu g mL(-1)), solasonine (50 mu M), solamargine (10, 15, and 20 mu M), and equimolar mixtures of glycoalkaloids (10 and 15 mu M) reduced the development of eggs produced by the adult worms. Solamargine, containing the sugar chain moiety chacotriose, was more active than the solasonine, which contains solatriose sugar chain moiety. A synergistic effect was also observed for a mixture of solamargine and solasonine. Therefore, the alkaloidic extract of S. lycocarpum, and its major components, solamargine and solasonine, showed promising schistosomicidal activity.

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The incorporation of the curcumin into poly(lactic-co-glycolic)acid (PLGA) nanospheres by the nanoprecipitation technique, the characterization of the nanoparticles and the schistosomicidal activity of the curcumin-loaded into PLGA nanospheres were reported. The incorporation process occurred with high efficiency and the images of field-emission scanning electron microscopy (FESEM) revealed the production of spherically shaped particles. According to the dynamic light scattering measurements, the particles are nanometric and monodisperse. The curcumin-loaded PLGA nanoparticles (50 and 100 mu M) caused the death of all worms and a separation between 50% and 100% of Schistosoma mansoni couples at concentrations from 30 mu M. Moreover, the curcumin-loaded PLGA nanoparticles also decreased the motor activity and caused partial alterations in the tegument of adult worms. This study marks the first time that schistosomicidal activity has been reported for curcumin-loaded PLGA nanoparticles.

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The immune response expressed by IgG antibodies in BALB/c mice experimentally infected with Toxocara canis, was studied with the aim of verifying the possible in vivo cross-reactivity between antigens of T. canis and other parasites (Ascaris suum, Taenia crassiceps, Schistosoma mansoni, Strongyloides venezuelensis and Toxoplasma gondii). Experiments included three groups of mice: one infected only by T. canis, another with one of the other species of parasites and a third concomitantly infected with T. canis and the other species in question. Animals were bled by orbital plexus at 23, 38 and 70 days post infection (p.i.). Sera were analyzed for anti-Toxocara antibodies by ELISA and Immunoblotting, using excretion-secretion antigens (ES), obtained from culture of third-stage larvae of T. canis. For all experiments a control group comprised by ten non-infected mice was used. Only in the case of A. suum infection, in these experimental conditions, the occurrence of cross-reactivity with T. canis was observed. However, in the case of co-infection of T. canis - S. mansoni, T. canis - S. venezuelensis and T. canis - T. crassiceps the production of anti-Toxocara antibodies was found at levels significantly lower than those found in mice infected with T. canis only. Co-infection with S. mansoni or S. venezuelensis showed lower mortality rates compared to what occurred in the animals with single infections. Results obtained in mice infected with T. canis and T. gondii showed significant differences between the mean levels of the optical densities of animals infected with T. canis and concomitantly infected with the protozoan only in the 23rd day p.i.

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The in vitro schistosomicidal effects of the essential oil obtained from Tagetes erecta L. Asteraceae, leaves (TE-EO) collected in Brazil against Schistosoma mansoni worms are reported in this paper. The oil caused a significant decrease in the motor activity at 50 µg/mL as minimal concentration after 24 h. This oil also caused death of all the parasites and the separation of coupled pairs into individual male and female at 100 µg/mL after 24 h. The viability of adult worm groups treated with the TE-EO at 100 µg/mL was similar to that of groups treated with praziquantel (positive control). In addition, the oil promoted the inhibition of eggs development at all the tested concentrations. These data indicate that the TE-EO could be considered as a promising source for the development of new schistosomicidal agents.

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Die tropische Süsswasserschnecke Biomphalaria glabrata gehört zu der Familie der Planorbidae, welche als einziges Taxon der Gastropoden Hämoglobin als Sauerstofftransportprotein verwenden. Als Zwischenwirt des Bilharzioseerregers Schistosoma mansoni ist B. glabrata von tropenmedizinischer Interesse. Das extrazelluläre BgHb zeigt sich mit einem Anteil von 95% als Hauptprotein in der Hämolymphe. Dieses setzt sich aus Polypeptidketten mit je 240kDa zusammen. Diese wiederrum lassen sich in 13-Häm-Domänen und eine deutlich kleinere N-terminalen nicht Häm-Domäne untergliedern. Die Sequenzierung von zwei der drei Untereinheiten des BgHb (BgHb1, BgHb2) ermöglichte die rekombinante Expression ganzer Untereinheiten in Insektenzellen, und die Expression einiger BgHb2-Konstrukte in E. coli Zellen. Im Rahmen meiner Arbeit gelang es, BgHb1 in biologisch aktiver Form in Insektenzellen zu exprimieren. Das aus dem Überstand der Insektenzellen aufgereinigte rekombinante BgHb1 zeigte eine immunologische Identität mit nativen BgHb. Strukturelle Analysen belegten zudem die Assemblierung des rekombinanten BgHb1 zu einer dem nativen Protein gleichenden Quartärstruktur. Demnach konnte in meiner Arbeit der Nachweis erbracht werden, dass eine einzelne Isoform in der Lage ist, zur Quartärstruktur zu assemblieren. Zusätzlich ergaben Sauerstoffbindungsanalysen, dass das rekombinante BgHb1 reversibel Sauerstoff binden kann.rnIn den restlichen 5% der B. glabrata Hämolymphe zeigt sich ein rudimentäres Hämocyanin, welches für den Sauerstofftransport keine Rolle zu spielen scheint, und ein rosettenförmiges Protein, das es aufzuklären galt. Durch massenspektrometrische Analysen erhaltene Peptidfragmente zeigten eine hohe Sequenzähnlichkeit zu den löslichen Acetylcholin -Bindeproteinen anderer Mollusken. Diese AChBP zeigen eine hohe Sequenzähnlichkeit zur Ligandenbindedomäne von Rezeptoren der Cys-Loop-Proteinfamilie.rnDatenbankrecherchen deckten die Existenz zweier Isoformen auf

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The breadth of material found in surgical pathology services in African countries differs from the common spectrum of "the West". We report our experience of a voluntary work in the pathology departments of Blantyre and Lilongwe, Malawi. During a 6-week period, 405 cases (378 histology and 27 cytology cases) were processed. The vast majority showed significant pathological findings (n = 369; 91.1 %): 175 cases (47.4 %) were non-tumoral conditions with predominance of inflammatory lesions, e.g., schistosomiasis (n = 11) and tuberculosis (n = 11). There were 39 (10.6 %) benign tumors or tumor-like lesions. Intraepithelial neoplasia of the cervix uteri dominated among premalignant conditions (n = 15; 4.1 %). The large group of malignancies (n = 140; 37.9 %) comprised 11 pediatric tumors (e.g., rhabdomyosarcoma, small blue round cell tumors) and 129 adult tumors. Among women (n = 76), squamous cell carcinomas (SCCs) of the cervix uteri predominated (n = 25; 32.9 %), followed by breast carcinomas (n = 12; 15.8 %) and esophageal SCC (n = 9; 11.8 %). Males (n = 53) most often showed SCC of the esophagus (n = 9; 17.0 %) and of the urinary bladder (n = 7; 13.2 %). Lymphomas (n = 7) and Kaposi's sarcomas (n = 6) were less frequent. Differences compared to the western world include the character of the conditions in general, the spectrum of inflammatory lesions, and the young age of adult tumor patients (median 45 years; range 18-87 years). Providing pathology service in a low-resource country may be handicapped by lack of personnel, inadequate material resources, or insufficient infrastructure. Rotating volunteers offer a bridge for capacity building of both personnel and the local medical service; in addition, the volunteer's horizons are broadened professionally and personally.

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Praziquantel (PZQ), prescribed as a racemic mixture, is the most readily available drug to treat schistosomiasis. In the present study, ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-ESI-QTOFMS) based metabolomics was employed to decipher the metabolic pathways and enantioselective metabolic differences of PZQ. Many phase I and four new phase II metabolites were found in urine and feces samples of mice 24h after dosing, indicating that the major metabolic reactions encompassed oxidation, dehydrogenation, and glucuronidation. Differences in the formation of all these metabolites were observed between (R)-PZQ and (S)-PZQ. In an in vitro phase I incubation system, the major involvement of CYP3A, CYP2C9, and CYP2C19 in the metabolism of PZQ, and CYP3A, CYP2C9, and CYP2C19 exhibited different catalytic activity toward the PZQ enantiomers. Apparent Km and Vmax differences were observed in the catalytic formation of three mono-oxidized metabolites by CYP2C9 and CYP3A4 further supporting the metabolic differences for PZQ enantiomers. Molecular docking showed that chirality resulted in differences in substrate location and conformation, which likely accounts for the metabolic differences. In conclusion, in silico, in vitro, and in vivo methods revealed the enantioselective metabolic profile of praziquantel.

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Live vaccine vectors are usually very effective and generally elicit immune responses of higher magnitude and longer duration than nonliving vectors. Consequently, much attention has been turned to the engineering of oral pathogens for the delivery of foreign antigens to the gut-associated lymphoid tissues. However, no bacterial vector has yet been designed to specifically take advantage of the nasal route of mucosal vaccination. Herein we describe a genetic system for the expression of heterologous antigens fused to the filamentous hemagglutinin (FHA) in Bordetella pertussis. The Schistosoma mansoni glutathione S-transferase (Sm28GST) fused to FHA was detected at the cell surface and in the culture supernatants of recombinant B. pertussis. The mouse colonization capacity and autoagglutination of the recombinant microorganism were indistinguishable from those of the wild-type strain. In addition, and in contrast to the wild-type strain, a single intranasal administration of the recombinant strain induced both IgA and IgG antibodies against Sm28GST and against FHA in the bronchoalveolar lavage fluids. No anti-Sm28GST antibodies were detected in the serum, strongly suggesting that the observed immune response was of mucosal origin. This demonstrates, to our knowledge, for the first time that recombinant respiratory pathogens can induce mucosal immune responses against heterologous antigens, and this may constitute a first step toward the development of combined live vaccines administrable via the respiratory route.

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Schistosomiasis is the major neglected tropical helminthic disease worldwide. Current knowledge on the epidemiology of schistosomiasis in Guinea-Bissau is scarce and regarding to the absence of Schistosoma haematobium (S.h.). Therefore, a pilot study was undertaken to assess the prevalence and morbidity due to S.h. infection in randomly selected 90 children and adolescents aged 6 to 15 years. Prevalence of S.h. infection was 20.00 % (18/90). Microhematuria was observed in 61.11 % (11/18) of S.h.-egg-excreting vs. 37.50 % (27/72) of non-S.h.-egg-excreting children p ≤ 0.01. Body mass index (BMI) was less than 15 kg/m(2) in 52/90 (57.78 %) of all children and adolescents, but this proportion increased to 66.67 % (12/18) in S.h.-infected children who were more frequently stunted and wasted than in non-infected children. The mean weight-for-age Z score (WAZ) was reduced in S.h. infected as compared to non-infected children (-1.48 ± 1.08 SD vs. -0.80 ± 1.11 SD; p ≤ 0.01). To our knowledge, this is the first epidemiologic report on S. haematobium infection in Guinea-Bissau since 22 years. Even in this relatively small study sample, it appears that S. haematobium, besides the well-known symptoms such as hematuria, leads to significant, albeit commonly unacknowledged morbidity such as stunting and wasting. These observations underscore the notion that this vulnerable but neglected population urgently needs to be targeted for implementation of measures for treatment and control.

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An epidemiologic survey among four administrative villages around Poyang Lake, in Jiangxi Province, China (two experimental and two controls) is being conducted to determine if bovine infections are responsible for the persistence of human schistosomiasis transmission on Yangtze River marshlands. A previously published paper presented the experimental design and baseline data for humans and bovines. This paper presents basic data for the four villages using remote sensing, and baseline data for snails that includes geographic information systems and remote sensing technology to classify the areas of bovine grazing ranges and habitats suitable for snails. A new method for sampling Oncomelania snails in China is used to determine the distribution, density, and infection rates of snails throughout the grazing ranges from season to season over a four-year period. Hypothetically, treating bovines should reduce infection rates in snails to below the critical number necessary to maintain infections in man and bovines.

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Background: Eosinophils are granulocytic white blood cells implicated in asthma and atopic disease. The degree of eosinophilia in the blood of patients with asthma correlates with the severity of asthmatic symptoms. Quantitative trait loci (QTL) linkage analysis of eosinophil count may be a more powerful strategy of mapping genes involved in asthma than linkage analysis using affected relative pairs. 1 Objective: To identify QTLs responsible for variation in eosinophil count in adolescent twins. Methods: We measured eosinophil count longitudinally in 738 pairs of twins at 12, 14, and 16 years of age. We typed 757 highly polymorphic microsatellite markers at an average spacing of similar to5 centimorgans across the genome. We then used multipoint variance components linkage analysis to test for linkage between marker loci and eosinophil concentrations at each age across the genome. Results: We found highly significant linkage on chromosome 2q33 in 12-year-old twins (logarithm of the odds = 4.6; P = .000002) and suggestive evidence of linkage in the same region in 14-year-olds (logarithm of the odds = 1.0; P = .016). We also found suggestive evidence of linkage at other areas of the genome, including regions on chromosomes 2, 3, 4, 8, 9, 11, 12, 17, 20, and 22. Conclusion: A QTL for eosinophil count is present on chromosome 2q33. This QTL might represent a gene involved in asthma pathophysiology.

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Schistosomes are parasitic blood flukes, responsible for significant human disease in tropical and developing nations. Here we review information on the organization of the cytoskeleton and associated motor proteins of schistosomes, with particular reference to the organization of the syncytial tegument, a unique cellular adaptation of these and other neodermatan flatworms. Extensive EST databases show that the molecular constituents of the cytoskeleton and associated molecular systems are likely to be similar to those of other eukaryotes, although there are potentially some molecules unique to schistosomes and platyhelminths. The biology of some components, particular those contributing to host-parasite interactions as well as chemotherapy and immunotherapy are discussed. Unresolved questions in relation to the structure and function of the tegument relate to dynamic organization of the syncytial layer. (C) 2004 Wiley Periodicals, Inc.

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We live in the era of post-genomics, a term that was, until recently, inappropriate when considering the blood flukes of humans because of the relative lack of knowledge of the schistosome genome. The position has, however, changed dramatically following the recent publication of two landmark papers on transcriptome analysis of Schistosoma japonicum and Schistosoma mansoni. In a quantum leap, both studies report on the identification of many novel genes and genes not previously known from schistosomes. The datasets provide new insights into the biology of the schistosomes and offer an opportunity for identification of potential antischistosome vaccine candidates and drug targets. Remarkable recent progress has also been achieved in genomic sequencing, and completed genomes for both species can be expected shortly.

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Hepatosplenic measurements among 550 Chinese subjects, aged 3-59 years from Yueyang city-a nonendemic area for schistosomiasis in Hunan province, China-were performed to define normal ranges of ultrasound organometry for assessing hepatosplenic, morbidity in Schistosoma japonicum infection. Measurements included the size of the liver (left lobe and right lobe), the main portal vein stem, the peripheral periportal vein branches, and spleen length and thickness. The results document the significant relationship between body height and organometric parameters. The reference values stratified by body height improve the accuracy of assessment. Thus, height-based normal ranges established in this study can be applied in hospital routine and in field studies of patients infected with S. japonicum in Hunan province and in other endemic areas of China. (C) 2004 Elsevier B.V. All rights reserved.