Extra-tissular Schistosoma mansoni egg granulomata in the peritoneal cavity of mice

The presence of Schistosoma mansoni eggs surrounded by inflammatory cells were detected within the peritoneal cavity of experimentally infected mice. The histological and ultrastructural analysis revealed the predominantly macrophagic composition of these structures. The presence of epithelioid cells, macrophages in different stages of activation and the architectural pattern of the cells, characterize these structures as extra-tissular true granulomas. Granulomas much similar to those observed in the peritoneal cavity of infected mice were also detected after the intraperitoneal injection of viable eggs in non-infected mice. Collagen fibers were observed in between the inflammatory cells of granulomas obtained 10 weeks after infection and 48 hours after the injection of viable eggs into the peritoneal cavity. In later times of infection or injection the amount of collagen fibers increases resulting in a typical pattern of healed schistosoma egg granulomas. The possible influence of the immune response on the genesis of the granulomatous reaction as well as the influence of the vascularized connective tissue on this process is discussed.

Scanning electron microscopy of the egg and the first instar larva of Dermatobia hominis (Diptera, cuterebridae)

The egg and the first instar larva of Dermatobia hominis were described based on observation with a scanning electron microscope.

Morphological observations on the egg and first instar larva of Metacutereba apicalis (Diptera: Cuterebidae)

Descriptions are given of the egg and first intar larvar of Metacutereba apicalis (Diptera: Cuterebridae) when viewed by light and scanning electronic microscopes.

Morphology of the EGG of Sarcodexia lambens (Diptera: sarcophagidae)

The egg of Sarcodexia lambens (Diptera: Sarcophagidae) is described on the basis of scanning electron microscopy.

What Belongs Where? Variable Selection for Zero-Inflated Count Models with an Application to the Demand for Health Care

This paper develops stochastic search variable selection (SSVS) for zero-inflated count models which are commonly used in health economics. This allows for either model averaging or model selection in situations with many potential regressors. The proposed techniques are applied to a data set from Germany considering the demand for health care. A package for the free statistical software environment R is provided.

(Don’t) Make My Vote Count

Proponents of proportional electoral rules often argue that majority rule depresses turnout and may lower welfare due to the 'tyranny of the majority' problem. The present paper studies the impact of electoral rules on turnout and social welfare. We analyze a model of instrumental voting where citizens have private information over their individual cost of voting and over the alternative they prefer. The electoral rule used to select the winning alternative is a combination of majority rule and proportional rule. Results show that the above arguments against majority rule do not hold in this set up. Social welfare and turnout increase with the weight that the electoral rule gives to majority rule when the electorate is expected to be split, and they are independent of the electoral rule employed when the expected size of the minority group tends to zero. However, more proportional rules can increase turnout within the minority group. This effect is stronger the smaller the minority group. We then conclude that majority rule fosters overall turnout and increases social welfare, whereas proportional rule fosters the participation of minorities.

Fecal calprotectin more accurately reflects endoscopic activity of ulcerative colitis than the Lichtiger Index, C-reactive protein, platelets, hemoglobin, and blood leukocytes.

BACKGROUND: The correlation between noninvasive markers with endoscopic activity according to the modified Baron Index in patients with ulcerative colitis (UC) is unknown. We aimed to evaluate the correlation between endoscopic activity and fecal calprotectin (FC), C-reactive protein (CRP), hemoglobin, platelets, blood leukocytes, and the Lichtiger Index (clinical score). METHODS: UC patients undergoing complete colonoscopy were prospectively enrolled and scored clinically and endoscopically. Samples from feces and blood were analyzed in UC patients and controls. RESULTS: We enrolled 228 UC patients and 52 healthy controls. Endoscopic disease activity correlated best with FC (Spearman's rank correlation coefficient r = 0.821), followed by the Lichtiger Index (r = 0.682), CRP (r = 0.556), platelets (r = 0.488), blood leukocytes (r = 0.401), and hemoglobin (r = -0.388). FC was the only marker that could discriminate between different grades of endoscopic activity (grade 0, 16 [10-30] μg/g; grade 1, 35 [25-48] μg/g; grade 2, 102 [44-159] μg/g; grade 3, 235 [176-319] μg/g; grade 4, 611 [406-868] μg/g; P < 0.001 for discriminating the different grades). FC with a cutoff of 57 μg/g had a sensitivity of 91% and a specificity of 90% to detect endoscopically active disease (modified Baron Index ≥ 2). CONCLUSIONS: FC correlated better with endoscopic disease activity than clinical activity, CRP, platelets, hemoglobin, and blood leukocytes. The strong correlation with endoscopic disease activity suggests that FC represents a useful biomarker for noninvasive monitoring of disease activity in UC patients.

Sarcopromusca pruna (Diptera: Muscidae) as an egg transport host of Dermatobia hominis (Diptera: Cuterebridae) in the cacau region of Bahia, Brazil

Sarcopromusca pruna appears to be the predominant transport host for Dermatobia hominis eggs among cattle herds in central eastern Bahia, Brazil. In the study area, two seasonal peaks of S. Pruna abundance coincide with those of Dermatobia, from mid July through late September and from mid November until early January, two periods of moderate monthly rainfall between anual extremes. Among more than 26,000 flies examined during the study, 75 (all female S. pruna) bore Dermatobia eggs. Certain aspects of Dermatobia behavior and ovoposition habits in the field are also discussed.

Short and long-term effects of azadirachtin A on development and egg production of Rhodnius prolixus

Azadirachtin A was given through a blood meal to 4th-instar larvae and to adult females of Rhodnius prolixus. Development (ecdysis) and egg production were inhibited in a dose-dependent manner. Long-term experiments with subsequent four feedings on azadirachtin-free blood were performed with 4th-instar larvae and with adult females. Only in the low-dose azadirachtin larval groups (0.01 and 0.1 microng/ml of blood), development was partially restored; after a single 1.0 microng/ml treatment about 50% of the treated larvae were still alive 120 days later without any adult emergence. Similarly fed females had a dose-dependent lower survival and egg deposition rate. The results are discussed in relation to the mode of azadirachtin A action.

Ultrastructure of the egg of Muscina stabulans and Synthesiomyia nudiseta (Diptera: Muscidae)

The eggs of Muscina stabulans and Synthesiomyia nudiseta are morphologically described, based on scanning electron microscope (SEM).

Schistosomiasis mansoni in three localities of western lowland of the state of Maranhão before and after mass treatments

A cross-sectional study for schistosomiasis was carried out in the localities of Aliança, Alegre and Coroatá (districts of Cururupu, São Bento and São João Batista, respectively) in the lowland of the state of Maranhão, after respectively 13, 11 and 4 mass treatments with oxamniquine in the period of ten years (1977-1987). The study included clinical and quantitative fecal examination, skin test for Shistosoma mansoni infection, evaluation of man-water contact of the total population (829 persons) in the three localities and other epidemiological investigations such as infection rate and dynamics of the snail population. After 13 mass treatments in Aliança, the prevalence of S. mansoni infection was reduced from 57.9% to 7.4%. In Coroatá with 11 mass treatments the prevalence fell from 69.2% to 12.8% and in Alegre, with only 4 mass treatments there was pratically no reduction in prevalence: 22.9% to 21%. After mass treatments the type II hepatointestinal clinical form was 10.8% in Aliança, 17.9% in Alegre and 18% in Coroatá. The hepatosplenic (type III) form was not seen in Aliança and Coroatá but unexplanably it was 7.6% in Alegre. There was no correlation between the egg load elimination and the clinical forms.

The role of egg antigens, cytokines in granuloma formation in murine schistosomiasis mansoni

The induction of granuloma formation by soluble egg antigens (SEA) of Schistosoma mansoni is accompanied by T cell-mediated lymphokine production that regulates the intensity of the response. In the present study we have examined the ability of SDS-PAGE fractioned SEA proteins to elicit granulomas and lymphokine production in infected and egg-immunized mice. At the acute stage of infection SEA fractions (<21, 25-30, 32-38, 60-66, 70-90, 93-125, and > 200 kD) that elicited pulmonary granulomas also elicited IL-2, IL-4 lymphokine production. At the chronic stage a diminished number of fractions (60-66, 70-90, 93-125, and > 200 kD) were able to elicit granulomas with an overall decrease in IL-2, IL-4 production. Granulomas were elicited by larval-egg crossreactive and egg-specific fractions at both the acute and chronic stage of the infection. Examination of lymphokine production from egg-immunized mice demonstrated that as early as 4 days IL-2 was produced by spleen cells stimulated with <21, 32-38, 40-46, 93-125, and >200 kD fractions. By 16 days, IL-2production was envoked by 8 of 9 fractions. IL-4 production at 4 days in response to all fractions was minimal while at 16 days IL-4 was elicited with the < 21, 25-30, 50-56, 93-125, and > 200 kD fractions. The present study reveals differences in the range of SEA fractions able to elicit granulomas and IL-2, IL-4 production between acute and chronic stages of infection. Additionally, this study demonstrates sequential (IL-2 followed by IL-4) lymphokine production during the primary egg antigen response.

Cross-sectional and evolutive studies of schistosomiasis mansoni in untreated and mass treated endemic areas in the southeast and northeast of Brazil

Cross-sectional and evolutive studies on schistosomiasis mansoni were carried out before and after mass treatment in the endemic areas of Capitao Andrade and Padre Paraíso, state of Minas Gerais, Riachuelo, state of Sergipe, Alhandra, state of Paraíba, and Aliança, Alegre and Coroatá, lowland of the state of Maranhao, Brazil, in the last eighteen years. The studies included clinical and fecal examination by the Kato-Katz quantitative technique, skin testfor Schistosoma mansoni infection, evaluation of man-water contact and other epidemiological investigations such as infection rate and dynamic of the snail population. Results showed: (1) Higher prevalence of S. mansoni infection, greater egg load elimination and higher and earlier morbidity of the chronic froms of the disease in the southeast areas of Capitao Andrade and Padre Paraíso; (2) The incidence of hepatosplenic form is higher in some family clusters, in whites and mullattos in all the endemic areas but develop earlier in the southeast; (3) The prevalence and morbidity of schistosomiasis are decreasing both in the mass treated northeast and in the untreated southeast areas; (4) The mass treatment reduces rapidily the prevalence of the infection and the morbidity of the disease but can not control it because of the frequent reinfections due to the intensity of man-water contact.

Pédiatrie. 4. La calprotectine fécale en pédiatrie: utilisation et interprétation [Pediatrics. Fecal calprotectin in children: use and interpretation].

Fecal calprotectin is a small protein released mainly by neutrophils. It is recognized as a reliable, easy and non-invasive biomarker of gastro-intestinal inflammation. Normal values vary with age, with higher cut-off values during the first year of life (<350 microg/g) than in children (<275 microg/g) or adults (<50 microg/g). Fecal calprotectin can be a useful tool in initial evaluation of recurrent abdominal pain, helping to distinguish between functional gastro-intestinal disorders, where it is normal, and inflammatory bowel disease (IBD). It is not a specific marker of IBD but is increased in other situations of gastro-intestinal inflammation. In patients with IBD, fecal calprotectin is used to monitor treatment response.