Magnetic properties of the double perovskites Sm2Mn1+x Co1-x O6 (x = 0, 0.05, 0.12 and 0.26).

The magnetic properties of the double perovskites Sm2Mn1+x Co1-x O6 (x = 0, 0.05, 0.12 and 0.26) were investigated. It was found that the Curie temperature, the lattice parameters and the net magnetic moments increased for increasing amounts of Co. An irreversible behavior was observed by measuring the magnetization after cooling the sample with and without applied magnetic fields (H). The temperature below which the irreversibility was observed is H dependent and the data were nicely fit to de Almeida-Thouless lines. The ac magnetic susceptibility was measured for frequencies f  in the range 0.03-10 kHz yielding [Formula: see text] for the shifting in the freezing temperature per decade of f . The spin-dynamics were found to follow a power-law with a product of the critical exponents [Formula: see text] of about 4.99. The overall results are understood within a framework where the variation in the bonding angle associated to the super-exchange interactions are taken into consideration.

Prevalence of enteroparasitic infections and related hormonal and immunological repercussions that may compromise students' physical performance.

The aim of this study was to evaluate the prevalence of enteroparasitic infections in students and their hormonal and immunological repercussions on physical development. Students of basic education of both sexes were evaluated. Parasitological stool tests were performed using the Hoffman and Kato-Katz methods. The students were divided into two groups: a control group (negative parasitological examination, N=25) and an infected group (positive parasitological test, N=25). Anthropometric variables (height, weight, and BMI), concentrations of hormones (melatonin and cortisol), cytokine/chemokine levels (IL-1ß, IL-6, IL-8, IL-10, IL-12, IL-17 and TNF-α) and physical performance (aerobic capacity, upper- and lower-limb muscle strength and abdominal performance) were evaluated. The prevalence of parasitic infection among the students was 7.98%. No anthropometric differences were observed among the groups. IL-2 and TNF-α levels were higher and IL-8 levels were lower in serum from students who were positive for parasitic infection. Serum from students who were positive for parasitic infection showed higher levels of melatonin than that from parasitenegative students. No differences were observed in cortisol levels. Students who were positive for parasitic infection presented greater lower-limb strength and lower abdominal performance than parasite-negative students. In the parasitic infection group, IL-12 was positively correlated with melatonin. In the parasitic infection group, IL-8 showed a positive correlation with aerobic capacity, while IL-17 and TNF-α showed a positive correlation with abdominal performance. These data suggest that parasitic infections determine the profile of inflammatory cytokines and that melatonin may be involved in the control of this process to minimize tissue damage. Additionally, students' difficulty in practising physical exercises can be an indication of enteroparasitic infection.

Maternal-Foetal Diabetes Modifies Neonatal Fc Receptor Expression on Human Leucocytes.

This study investigated the expression of the neonatal Fc receptor (FcRn) in maternal blood, cord blood and placental cells and determined IgG levels in maternal blood and cord blood from diabetic mothers. Peripheral blood, cord blood and placenta samples were collected from 26 mothers with normoglycaemia (non-diabetic, ND group) and 52 with hyperglycaemia (26 with mild gestational hyperglycaemia, MGH group, and 26 with type 2 diabetes mellitus, DM-2 group). Cells expressing CD19(+) and FcRn were identified by flow cytometry. Total IgG and its subclasses were quantified by ELISA. Maternal blood from DM-2 and cord blood from MGH exhibited a higher proportion of CD19(+) expression by B cells. DM-2 showed a lower proportion of CD19(+) cells in placenta. FcRn expression increased in cells from cord blood and placenta from MGH. Maternal blood, cord blood and placenta cells from DM-2 showed lower FcRn expression. Blood IgG levels were lower in DM-2, and cord blood IgG levels were higher in MGH. The highest levels of IgG4 were detected in the blood of hyperglycaemic mothers. The highest IgG3 and IgG4 levels in cord blood were detected in MGH, and the lowest IgG2 and IgG3 levels in DM-2. Maternal hyperglycaemia compromised placental transfer of IgG1, IgG3 and IgG4. The results suggest that regardless of hyperglycaemia degree, it decreases FcRn expression in placenta and blood cells and compromises the production and transfer of antibodies from maternal blood to newborns.

Efeito do composto "mais vida" na ativação de macrófagos de ratos diabéticos / Effects of "mais vida", a commercial natural mix, on the activation of macrophages from diabetic rats

O objetivo deste trabalho foi avaliar a atividade funcional de macrófagos de ratos diabéticos, através da liberação do ânion superóxido, na presença do composto "mais vida". Os animais foram divididos em dois grupos, controle (N=20) e diabético (N=20). Avaliou-se a glicemia, massa corpórea e a liberação de superóxido pelos macrófagos de baço de ratos. O composto "mais vida" foi obtido através da mistura de extratos de sete plantas, sendo Orbignia martiana Rodr., Tabebuia avellanedae L.G., Arctium lappa L., Rosa centifolia L., Maytenus ilicifolia Mart., Vernonia condensata Baker e Thuja occidentalis L. Observou-se que glicemia foi maior no grupo diabético. A liberação espontânea do ânion superóxido pelos macrófagos foi menor no grupo diabético. O composto "mais vida", independente dos níveis glicêmicos, aumentou a liberação de superóxido dos macrófagos. Quando as células foram estimuladas pelos extratos vegetais isolados, também houve aumento na liberação do ânion superóxido pelos macrófagos em ambos os grupos. As maiores liberações de superóxido ocorreram quando os macrófagos foram estimulados pela Thuja occidentalis L., Rosa centifolia L., Tabebuia avellanedae L.G. e Maytenus ilicifolia Mart. Estes dados sugerem que a ativação de macrófagos pelo composto "mais vida" pode representar um mecanismo alternativo de defesa para infecções em indivíduos diabéticos.

This study investigated the effects of "mais vida", a commercial natural mix, on macrophages functional activity as evaluated by the superoxide release in diabetic rats. The animals were divided into two groups, control (N = 20) and diabetic (N = 20). This was achieved by determining blood glucose weight and the superoxide released by spleen macrophages. The "mais vida" mix was obtained by the combination of extracts from seven medicinal species, which were: Orbignia martiana Rodr., Tabebuia avellanedae L.G., Arctium lappa L., Rosa centifolia L., Maytenus ilicifolia Mart., Vernonia condensata Baker and Thuja occidentalis L. Blood glucose levels were significantly higher (p<0.05) in the diabetic group, as compared to blood glucose levels in the control group. Superoxide levels in macrophages isolated from normoglycemic rats were higher than those obtained from diabetic animals. The "mais vida" mix, independently of glycemic status, increased significantly the superoxide release in the macrophages. Each extract by itself also increased the superoxide release by phagocytes in the macrophages in both groups. The largest superoxide release occurred when the phagocytes were stimulated by Thuja occidentalis L., Rosa centifolia L., Tabebuia avellanedae L.G. and Maytenus ilicifolia Mart. In addition, the activation of macrophages by the "mais vida" mix may represent an additional protection mechanism for diabetic individuals against infections.

Diabetes induced immunological and biochemical changes in human colostrum.

AIM: This article describes the changes and relationships between biochemical and immunological parameters in the colostrum and serum of diabetic women. METHODS: Colostrum and blood samples were collected from 30 diabetic and 15 normoglycaemic women. Glucose, total protein, antibody, complement proteins (C3 and C4), fat and calorie content, amylase, lipase and superoxide dismutase (SOD) were determined. RESULTS: Glucose was higher in both the colostrum and serum of diabetic mothers compared to that of their normoglycaemic counterparts. In both groups, total protein was higher in colostrum than in serum. IgA and IgG were lower in the colostrum of hyperglycaemic mothers, whereas IgM did not vary between the groups. Colostral C3 protein was significantly lower in diabetic mothers, but colostral C4 protein was similar between normoglycaemic and hyperglycaemic mothers. Fat content was lower in the colostrum of the diabetic mothers, although calorie content did not vary between the groups. Amylase was lower in colostrum than in serum in both groups. Lipase was higher in the colostrum and serum of diabetic mothers. Colostral SOD was similar between the groups. CONCLUSIONS: Our results support the hypothesis that the colostrum of diabetic mothers suffers biochemical and immunological alterations that affect the levels of its components.

High dietary carbohydrate and pancreatic lesion.

The ability of high dietary carbohydrate to induce acute pancreatitis was investigated in groups of 16, 21-day and 15-month old rats fed different carbohydrate diets for 30 days. Significantly increased levels of serum amylase (2-fold), phospholipids (50%), phosphorus (2-fold), and lipoperoxides (8-fold) were observed in 15-month old rats fed a high-carbohydrate diet, compared to rats fed a diet with normal carbohydrate levels, indicating peroxidation of membrane lipids which caused final cell death and pancreatic lesion. Serum Cu-Zn superoxide dismutase activity was not altered. Daily administration of bovine Cu-Zn superoxide dismutase conjugated with polyethylene glycol prevented the serum level alterations and pancreatic lesions, indicating that the superoxide radical has a role in dietary carbohydrate-induced acute pancreatitis. No biochemical changes were observed in rats in which treatment was initiated on the 21st day of life indicating that this is an age-related lesion.

High dietary carbohydrate and pancreatic lesion

The ability of high dietary carbohydrate to induce acute pancreatitis was investigated in groups of 16, 21-day and 15-month old rats fed different carbohydrate diets for 30 days. Significantly increased levels of serum amylase (2-fold), phospholipids (50 per cent ), phosphorus (2-fold), and lipoperoxides (8-fold) were observed in 15-month old rats fed a high-carbohydrate diet, compared to rats fed a diet with normal carbohydrate levels, indicating peroxidation of membrane lipids which caused final cell death and pancreatic lesion. Serum Cu-Zn superoxide dismutase activity was not altered. Daily administration of bovine Cu-Zn superoxide dismutase conjugated with polyethylene glycol prevented the serum level alterations and pancreatic lesions, indicating that the superoxide radical has a role in dietary carbohydrate-induced acute pancreatitis. No biochemical changes were observed in rats in which treatment was initiated on the 21st day of life indicating that this is an age-related lesion