Identification ofSchistosoma haematobium soluble egg antigens that elicit human granuloma formation in vitro

Schistosoma haematobium soluble egg antigens (SH SEAs) induce intense granulomas in human hosts that often culminate in severe disease. In an attempt to identify the SH SEA fractions that are responsible for pathology, we combined T-cell Western blotting and an in vitro model of granuloma formation. Whole SH SEAs were dotted onto nitrocellulose pieces or were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electrotransferred onto nitrocellulose paper. Horizontal strips bearing the separated antigens were solubilized in dimethylsulfoxide and precipitated in carbonate/bicarbonate buffer. Antigen-free and antigen-bearing particles were used to stimulate peripheral blood mononuclear cells (PBMCs) obtained fromS. haematobium-infected patients and sex- and agematched healthy controls to form granulomas in vitro. Whole SH SEA-bearing nitrocellulose particles elicited in vitro formation of granulomas by PBMCs from infected donors. The response was similar in sensitivity, specificity, and reproducibility to that evoked by SH SEA-bound polyacrylamide beads. The results obtained in samples from 30 patients and 10 controls tested with SH SEA-separated fractions revealed that SEA bands of 84 000, 63 000, 57 000, 55 000, 40 000, 30 000, and 28 000 Da elicited in vitro granuloma reactions by PBMCs of almost all infected patients. Conversely, separated soluble adult-worm antigens failed to stimulate PBMCs of infected patients to form granulomas. This study is the first to identify the SH SEA fractions that evok in vitro granuloma formation and represents an initial step toward the development of an anti-urinary schistosomiasis pathology vaccine.     

Dysferlin mutations in LGMD2B, Miyoshi myopathy, and atypical dysferlinopathies

DYSF encoding dysferlin is mutated in Miyoshi myopathy and Limb-Girdle Muscular Dystrophy type 2B, the two main phenotypes recognized in dysferlinopathies. Dysferlin deficiency in muscle is the most relevant feature for the diagnosis of dysferlinopathy and prompts the search for mutations in DYSF. DYSF, located on chromosome 2p13, contains 55 coding exons and spans 150 kb of genomic DNA. We performed a genomic analysis of the DYSF coding sequence in 34 unrelated patients from various ethnic origins. All patients showed an absence or drastic decrease of dysferlin expression in muscle. A primary screening of DYSF using SSCP or dHPLC of PCR products of each of 55 exons of the gene was followed by sequencing whenever a sequence variation was detected. All together, 54 sequence variations were identified in DYSF, 50 of which predicting either a truncated protein or one amino-acid substitution and most of them (34 out of 54) being novel. In 23 patients, we identified two pathogenic mutations, while only one was identified in 11 patients. These mutations were widely spread in the coding sequence of the gene without any mutational "hotspot."     

A randomized trial of ceftriaxone versus trimethoprim-sulfamethoxazole to prevent ventriculoperitoneal shunt infection.

BACKGROUND AND PURPOSE: Shunt infection represents a particularly morbid condition, which can also result in mortality. In order to decrease the high morbidity and mortality rates, prevention is an essential step. The purpose of this study was to compare the prophylactic use of ceftriaxone and trimethoprim-sulfamethoxazole (SXT) for the prevention of ventriculoperitoneal (VP) shunt infection. METHODS: In this prospective, single-institution, randomized clinical trial, 107 children with hydrocephalus and an indication for shunting were randomly assigned to prophylaxis with ceftriaxone (n = 50) or SXT (55), each administered as a single dose during anesthesia and two divided doses postoperatively. Patients were followed up for at least one year. RESULTS: The mean age of patients was 15 months, and 85% were aged 6 months or younger. During the first postoperative year, meningitis occurred in 13.5% of patients receiving ceftriaxone and 14.5% of the SXT group, with no statistically significant difference between the groups. Younger age, presence of cerebrospinal fluid leakage and aqueductal stenosis as a cause of hydrocephalus showed significant correlation with meningitis occurrence on univariate analysis. However, only the latter 2 factors were associated with meningitis on multivariate analysis. The risk of shunt infection did not correlate with the gender of the patient, time of VP shunt surgery, or duration of hospitalization for shunting. CONCLUSION: Ceftriaxone and SXT showed similar efficacy in preventing shunt infection. Cerebrospinal fluid leakage before or after VP shunt placement and aqueductal stenosis were independent risk factors for meningitis after VP shunt.     

Homocysteine,lipoprotein (a): risk factors for coronary heart disease

Our data suggest that the hyperhomocysteinemia and/or increased plasma level of lipoprotein Lp(a) are risk factors for coronary heart disease. We investigated 178 patients who underwent complete cardiac examination comprising coronary angiography and biological analysis (CT, HDL-c, LDL-c, TG, and apoAI, apoB, homocysteine and Lp(a)). Patients presenting a significant stenosis of the coronary artery ( 50% of the vascular lumen) were considered as cases (113 patients). Those without stenosis or with non-significant stenosis (< 50% of the vascular lumen) were used as controls (65 subjects). Homocysteinemia was significantly higher in cases than in control subjects (8.26 mol/L (2.34 versus 17.85 (2.34, p < 0.001). A strong association between coronary heart disease and homocystein has been found (Eta(2) = 0.76). The OR were 0.16 when homocystein level was lower than 15 mol/L, and 27.78 when homocysteine level was upper than or equal to 15 mol/L. The RR was 5.16 (95% IC = 3.66-6.66, p < 0.001). Even though there was a significant correlation between tabagic impregnation and homocysteinemia (Spermann's rho = 0.37, p < 0.05), there was no interactive effect between these two factors and coronary disease (Wald khi2 = 0.086, p > 0.05). Therefore, no association was found between homocyteinemia and other coronary heart disease risk factors. The Lp(a) levels were significantly higher in cases than in controls subjects (188 (84 mg/L in control subjects versus 590 (199 in cases, p < 0.001). A stronger relationship was noted between coronary heart disease and Lp(a) (Eta (2) = 0.66). The OR were 0.09 when lipoprotein (a) levels were lower than 350 mg/L, and 5,88 when Lp(a) levels were higher than or equal to 350 mg/L. The estimate RR was 6.47 (95% IC = 4.39-8.55, p < 0.001). The level of Lp(a) was positively correlated with the severity of coronary heart disease (Spermann's rho = 0.95, p < 0.001). A weak correlation between Lp(a) and LDL-c was observed (Spermann's rho = 0.12, p = 0.048). But the multivariate analysis didn't show interactive effect between these two factors and coronary disease (khi2 de Wald = 0.264, p > 0.05). No association was noted between Lp(a) and the others risk factors. Moreover, a positive correlation between the levels of homocysteine and those of Lp(a) was found (Spermann's rho = 0.54, p < 0.001). In contrast their effect on coronary heart disease seems to be independant (Wald khi2 = 2.957, p > 0.05). Thus, these two parameters appear as independant risk factors for coronary heart disease.     

Effects of Various Environmental Stress Paradigms and Adrenalectomy on the Expression of Autoimmune Type 1 Diabetes in the Non-obese Diabetic (NOD) Mouse

The effects of long-term chronic stress (induced by repeated restraint, overcrowding or both), short-term chronic stress (induced by a triad of stressors over a short period of time early in life) and adrenalectomy were investigated on the prevalence, on the degree of insulitis and various physiological and immunological parameters in the NOD mouse, a spontaneous model of type I-insulin-dependent diabetes mellitus (IDDM). Long-term chronic stress, obtained by restraint once a week or overcrowding, significantly protected NOD females, while both applied concomitantly had only a tendency to protect against diabetes. In contrast, short-term chronic stress had no significant effect on diabetes expression, whereas adrenalectomy resulted in a trend toward accelerated diabetes onset. The various long-term chronic stress paradigms exerted different effects on the progression of insulitis: repeated restraint tended to protect against insulitis, overcrowding had no effect but, when associated with restraint, significantly counteracted the beneficial effect of restraint alone. Adrenalectomy and short-term chronic stress had no significant effect on the development of insulitis. Various parameters, such as body, thymus and spleen weights, thymus and spleen cellularities, mitogen-induced spleen cell proliferation and serum corticosterone levels were also studied under the various experimental conditions. Taken together, the observations suggest that stressors modulate the expression of spontaneous autoimmune diabetes by exerting pleiotropic effects on immune and/or inflammatory components at the pancreas level and on peripheral glucose metabolism.     

HLA antigens in schistosomal hepatic fibrosis patients with haematemesis

20 patients of schistosomal hepatic fibrosis and splenomegaly (SHF) with and without haematemesis were examined. Typing for HLA-A, B and C antigens in these patients were compared with those of a group of 100 Egyptian controls. The study showed the presence of an association between HLA-A1 and B5 antigens in SHF cases. However, there was no significant association between HLA antigens and SHF cases with haematemesis.     

Effect of hydrocortisone on immune system of the lizard,Chalcidesocellatus II. Differential action on T and B lymphocytes

Lymphocytes of thymus, spleen, peripheral blood (PB) and bone marrow (BM) collected from adult lizards, $\text{Chalcides}$$\text{ocellatus}$ were cultured for 24 hr in the presence of 10^?3M hydrocortisone acetate (HC) in order to assess the effect of in vitro HC on lizard T and B cell viability. The results indicated that HC induced stepwise, time-dependent mortality of the majority of thymocytes carrying T cell specific antigen(s) (TSA), 30–50% of T cells of spleen, PB and BM, and of a proportion of splenic B lymphocytes. Administration of 1 mg/g body weight HC to adult $\text{Ch}$. $\text{ocellatus}$ lead to depletion of all TSA⁺ thymocytes. In contrast, T lymphocytes in the peripheral lymphoid compartments revealed both sensitivity and resistance to HC; similarly, B lymphocytes constituted susceptible and resistant subpopulations.     

Genetic susceptibility to visceral leishmaniasis in The Sudan: linkage and association with IL4 and IFNGR1

Longitudinal studies in Sudan show ethnic differences in incidence and clinical phenotypes associated with Leishmania donovani. Immunologically, bias in type 1 vs type 2 cytokine responses is important. To determine whether polymorphisms at IL4/IL9 or IFNGR1 contribute to susceptibility, we examined 59 multicase families of visceral leishmaniasis (VL) with/without post Kala-azar dermal leishmaniasis (PKDL). Multipoint nonparametric analysis (Allegro) linked IL4/IL9 to VL per se (P=0.002). Transmission disequilibrium testing with robust variance estimates confirmed association in the presence of linkage between VL per se and IL4 (P=0.008) but not IL9. Stepwise logistic regression analysis showed both IL4RP2 and IL4RP1 markers contributed significantly to the association, suggesting a common disease-associated haplotype. In contrast, IFNGR1 was linked (P=0.031) and associated (P=0.007) to PKDL but not VL or VL per se. Hence, polymorphism in a type 2 cytokine gene influences underlying susceptibility to VL, whereas IFNGR1 is specifically related to susceptibility to PKDL.