Schistosoma Mansoni Ova Research Articles

E-cadherin expression in macrophages dampens their inflammatory responsiveness in vitro, but does not modulate M2-regulated pathologies in vivo.

IL-4/IL-13-induced alternatively activated macrophages (M(IL-4/IL-13), AAMs or M2) are known to express E-cadherin, enabling them to engage in heterotypic cellular interactions and IL-4-driven macrophage fusion in vitro. Here we show that E-cadherin overexpression in Raw 264.7 macrophages inhibits their inflammatory response to LPS stimulation, as demonstrated by a reduced secretion of inflammatory mediators like interleukin (IL)-6, tumor necrosis factor (TNF) and nitric oxide (NO). To study the function of E-cadherin in M(IL-4/IL-13) macrophages in vivo, we generated macrophage-specific E-cadherin-deficient C57BL/6 mice. Using this new tool, we analyzed immunological parameters during two typical AAM-associated Th2-driven diseases and assessed Th2-associated granuloma formation. Although E-cadherin is strongly induced in AAMs during Taenia crassiceps helminth infections and allergic airway inflammation, its deletion in macrophages does not affect the course of both Th2 cytokine-driven diseases. Moreover, macrophage E-cadherin expression is largely redundant for granuloma formation around Schistosoma mansoni ova. Overall, we conclude that E-cadherin is a valuable AAM marker which suppresses the inflammatory response when overexpressed. Yet E-cadherin deletion in macrophages does not affect M(LPS+IFNγ) and M(IL-4) polarization in vitro, nor in vivo macrophage function, at least in the conditions tested.

Effect of Mass Chemotherapy with Praziquantel on the Prevalence of Schistosomiasis in School Children in Langai Community of Plateau State

Background: One of the main control measures for Schistosomiasis in Nigeria is mass chemotherapy with Praziquantel tablets in areas where the disease is prevalent. This study was carried out to determine the effect of drug treatment with Praziquantel on the prevalence of urinary and intestinal Schistosomiasis among school children. Methodology: Multi-staged sampling technique was used to select 218 school children. A structured interviewer administered questionnaire was used to gather data from the children; their urine and stool samples were assayed for Schistosoma haematobium and Schistosoma mansoni ova using the sedimentation method, before and after drug treatment with orally administered Praziquantel tablets at 40mg/kg body weight. Results: Before treatment with Praziquantel tablets, 14 subjects (6.4%) had S. haematobium ova in their urine samples while 17 subjects (7.8%), had S. mansoni ova in their stool samples. Male subjects of the ages 10-14year old had the highest prevalence of the disease. Six weeks after treatment, the prevalence of urinary schistosomiasis had been significantly reduced (with P = 0.03 and 0.05 respectively) to 0.5% in the studied population (cure rate of 92.9%) while that of intestinal schistosomiasis was 1.4% (cure rate of 82.4%). Conclusion: It was concluded that the prevalence of urinary and intestinal schistosomiasis among school children in Langai pre-intervention was 6.4% and 7.8 % respectively and drug treatment with Praziquantel, reduced these to 0.5% and 1.4% respectively. Praziquantel was also more effective in reducing the prevalence of urinary than intestinal schistosomiasisKey Words Prevalence, Schistosoma haematobium, Schistosoma mansoni, Praziquantel, Effectiveness

Schistosomal colonic disease.

This study evaluates 216 patients with schistosomal colonic disease, diagnosed by endoscopic biopsies at the Armed Forces Hospital, Riyadh. The colonoscopic appearance was suggestive of schistosomiasis in 98 of these patients (45.37%), Schistosoma mansoni ova in stool was detected in only 24 of these 216 patients (11.11%). The most common histopathological finding in colonic biopsies of these patients was Schistosoma mansoni ova in the colonic mucosa with no or mild inflammatory cells infiltrates. These findings correlate with the endoscopic appearances in most patients. The most common symptoms were abdominal pain or distention in 84 patients (38.88%). Sixty five patients (30.09%) had hepatosplenic schistosomiasis. Eight patients had schistosomal polyps and two patients had colonic malignancy in which no association between their malignancy and Schistosoma mansoni infection was established. After antischistosomal treatment follow up, sigmoidoscopy was normal in 28 patients who previously had abnormal endoscopic appearances. Colonoscopic examination is valuable in colonic schistosomiasis as it can show characteristic colonic lesions and colonic biopsies are diagnostic and correlates with histological findings.

Observations by Scanning Electron Microscopy of Miracidial Hatching from Schistosoma mansoni Ova

with a ventral holdfast 3.0 to 5.6 mm long had eggs 62 to 96 ,um long by 33 to 39 /m wide. Testicular length in those specimens was 53 to 1,024 /um. Because mature individuals infect the black drum, that fish can be considered a true definitive host as well as the only known vertebrate host. a ventral holdfast 3.0 to 5.6 m long had 62 to 96 ,um long by 33 to 39 /m wide. We thank Drs. J. Leon McGraw, Jr. and Ralph Lichtenfels for loaning us specimens. This study was conducted in cooperation with the U.S. Department of Commerce, NOAA, National Marine Fisheries Service, under PL 88-309, Project No. 2-382-R.

Acute schistosomiasis Mansoni in 10 boys. An outbreak in Caguas, Puerto Rico.

In August 1968 acute Manson's schistosomiasis occurred in 10 adolescent boys 2 to 8 weeks after swimming in the Turabo River. Clinical, laboratory, and serologic responses to infection were studied, and the river was surveyed for sources of infection. Striking variations in clinical manifestations were noted in the nine boys studied. One boy remained asymptomatic; six boys had fever and diarrhea; seven had hepatomegaly or splenomegaly, or both; and all had eosinophilia. Each boy had Schistosoma mansoni ova in his stool or rectal biopsy, or both. Fluorescent, complement-fixing, and flocculating antibodies were present 8 weeks after exposure, whereas circumoval precipitins did not appear until later. Skin test positivity increased from 56% to 100% between the eighth and 22nd week after exposure. Sewage effluent flows directly into the river, and 52 of 297 Biomphalaria glabrata collected shed S. mansoni cercariae.