Signaling of neuronal cell death by the p75NTR neurotrophin receptor

The neurotrophin receptor (p75NTR) is best known for mediating tropic support by participating in the formation of high-affinity nerve growth factor (NGF) receptor complexes with trkA, however, p75NTR more recently has been shown to act as a bona fide death-signaling receptor, which can signal independently of trkA. This article discusses the evidence for an active role of p75NTR in neuronal cell death and the mechanisms controlling this process, including roles for Bcl-2 family members, the c-jun stress kinase JNK, the transcription factor nuclear factor kappa B (NF kappa B), and caspases.

Effects of replacing meat with soyabean in the diet on sex hormone concentrations in healthy adult males

A randomised crossover dietary intervention study was performed to evaluate the effects of replacing meat protein in the diet with a soyabean product, tofu, on blood concentrations of testosterone, dihydrotestosterone, androstanediol glucuronide, oestradiol, sex hormone-binding globulin (SHBG), and the free androgen index (total testosterone concentration/SHBG concentration x 100; FAI). Forty-two healthy adult males aged 35-62 years were studied. Diets were isoenergetic, with either 150 g lean meat or 290 g tofu daily providing an equivalent amount of macronutrients, with only the source of protein differing between the two diets. Each diet lasted for 4 weeks, with a 2-week interval between interventions. Fasting blood samples were taken between 07.00 and 09.30 hours. Urinary excretion of genistein and daidzein was significantly higher after the tofu diet (P

Low prenatal vitamin D alters morphology, cell density and gene expression in adult rat brain: Correlations with schizophrenia

Statement of the study: Based on data from ecological and analytic epidemiological studies, we have proposed that low prenatal vitamin D is a candidate risk-modifying factor for schizophrenia. Previously, we demonstrated that low prenatal vitamin D adversely affected brain development in neonatal rats (Eyles et al, 2003). Here we examine the impact of both prenatal and early life hypovitaminosis D on various outcomes in the adult rat brain. Methods: Female Sprague-Dawley rats were made vitamin D deficient via the use of a special diet (Dyets CA) and lighting conditions that excluded UVB radiation. Animals were kept under these conditions for 6 weeks then mated with males kept under normal conditions. Vitamin deplete dams were kept under these conditions during pregnancy. Offspring from two test groups were examined. Offspring were either reared with dams repleted with vitamin D at birth or remained under deplete conditions till weaning. Both test groups were weaned under normal vitamin D conditions and remained so till testing at adulthood. We compared the brains of adult offspring kept under both test conditions with animals from control environments. Summary of results: We found a significant persistent dose-related increase in lateral ventricle volume and alterations in anterior cingulate and prefrontal cortical cell densities (consistent with the known prodifferentiation properties of this steroid). In both test groups we observed a reduced expression of NGF as well as a down-regulation of transcripts coding for GABAA alpha 4 receptor and two neuronal structural elements; MAP2 and Neurofilament L. Conclusion: These findings provide further evidence that vitamin D is involved in brain development. An increase in prefrontal cortical cell density, a reduction neuronal structural elements and persistent ventriculomegaly are all common anatomical findings in the brains of patients with schizophrenia. The specific reduction in transcripts for neuronal structural proteins but not GFAP is also in accordance with the proposal that frontal cortical architecture in schizophrenia reflects a reduction in connectivity rather than a reduction in glial processes(Goldman-Rakic and Selemon, 1997). These findings confirm the biological plausibility of early life hypovitaminosis D as a risk factor for schizophrenia.

The mechanism of inflammation in RelB deficient mice

RelB, NIK and TRAF6-deficient mice die prematurely with multi-organ inflammatory disease and apparent excessive myelopoiesis. While thymic development of CD4+CD25+ regulatory T cells (Treg) is reduced in TRAF6 deficient mice, the impact of this on inflammation is not known. Here we show that while RelB deficient thymic stroma is unable to sustain the development of Treg, surprisingly, FoxP3hi Treg are increased in the periphery. Peripheral expansion of Treg is driven by GITRligand, expressed by immature monocytes maintained by RelBdeficient stroma. RelB-deficient DC fail to activate Treg suppressor function. The data reveal the dual roles of RelB in both hemopoietic and stromal cells to maintain tolerance and contain inflammation through Treg and DC.

Binge eating symptoms, diet composition and metabolic characteristics of obese children and adolescents

This study aimed to determine the occurrence of symptoms of binge eating (BE) among children and adolescents seeking treatment for their obesity, as well as to evaluate their diet composition and metabolic characteristics. The Binge Eating scale (BES) was answered by 128 children and adolescents (10.77 +/- 2.04 years, BMI 29.15 +/- 4.98 kg/m(2), BMI Z score 2.28 +/- 0.46, 53.91% pubescent), who were classified into two subgroups-binge eaters (score greater than or equal to IS points) and non-binge eaters (score lower than 18 points). Anthropometric data, body composition and Tanner stages were collected and dietary evaluation conducted. Blood pressure was determined, and glucose, lipid profile and insulin assays were performed. insulin resistance was determined using HOMA-IR. BE symptoms were present in 39.06% of patients. Carbohydrate intake in diet composition was significantly higher among binge eaters. Children with BE did not demonstrate significant dissimilar metabolic characteristics when compared to their counterparts without BE. Therefore, BE seems to be a prevalent problem among children and adolescents seeking help for their obesity. When associated with obesity, this eating behaviour can influence macronutrient consumption through increased carbohydrate intake. Further research would be valuable to verify the reproducibility of these findings. (c) 2007 Elsevier Ltd. All rights reserved.

Uveitis in celiac disease with an excellent response to gluten-free diet: third case described

To describe the case of a patient with celiac disease who achieved a complete response to a gluten-free diet. A 28-year-old woman presented with diarrhea, oral ulcers, and refractory uveitis of 2.5-years duration. She was treated with prednisone, mydriatic drops, and infliximab with no response. She was referred to our hospital at which point her previous diagnosis of uveitis was confirmed; she was also diagnosed with right-sided sacro-iliitis. The patient did not have arthritis or any skin conditions. Three tests for fecal parasites and a fecal leukocyte were negative. Endoscopy revealed atrophic appearance of the duodenal mucosa. Biopsy showed atrophy of the duodenal villi with intra-epithelial lymphocytes, hyperplasia of the crypts, and chronic inflammatory infiltrate. The search for antiendomysial antibody was > 1/1,280. The patient was started on a gluten-free diet and after 3 months demonstrated significant improvement of gastrointestinal symptoms and uveitis, as well as a reduction of antiendomysial antibodies (1/80). After 6 months, there was complete remission of gastrointestinal symptoms and total control of uveitis. The antiendomysial antibody was negative at that time. Clinical uveitis as a manifestation of celiac disease has been described in only two cases in the literature. This case study is the third to demonstrate that uveitis is a clinical symptom that can be addressed in patients with celiac disease.

Searching behaviour and diet of Oystercatcher Haematopus ostralegus pairs feeding in their territories

Search path, searching behaviour and diet of pairs of Oystercatchers feeding in mudflat territories were studied during spring. females ate Nereis, Mya, small unidentified prey, probably Corophium, and a few Macoma, whereas males primarily ate Macoma. Even when female and male foraged in the same site, they often caught different prey. The combination of 'The Search-rate/Detection Model' (Gendron & Staddon 1983) and 'The Harvestable Prey Model' (Zwarts & Wanink 1993) provide the theoretical framework in which to explain these differences in diet. Macoma are thought to be more cryptic than Nereis, Mya and Corophium. Therefore females, while searching at a faster rate than their respective mates, caught far fewer cryptic prey, but a greater number of more conspicuous prey than their mates. On the basis of distances moved before and after capturing prey, males exhibited area-restricted searching for Macoma and Corophium. In contrast, females did not exhibit any area-restricted searching. it is suggested that the distribution of Macoma and Corophium available to males searching slowly was more clumped than that of these two prey species available to females searching more quickly.

The p.A2215D Thyroglobulin Gene Mutation Leads to Deficient Synthesis and Secretion of the Mutated Protein and Congenital Hypothyroidism with Wide Phenotype Variation

Context: Thyroglobulin (TG) is a large glycoprotein and functions as a matrix for thyroid hormone synthesis. TG gene mutations give rise to goitrous congenital hypothyroidism (CH) with considerable phenotype variation. Objectives: The aim of the study was to report the genetic screening of 15 patients with CH due to TG gene mutations and to perform functional analysis of the p. A2215D mutation. Design: Clinical evaluation and DNA sequencing of the TG gene were performed in all patients. TG expression was analyzed in the goitrous tissue of one patient. Human cells were transfected with expression vectors containing mutated and wild-type human TG cDNA. Results: All patients had an absent rise of serum TG after stimulation with recombinant human TSH. Sequence analysis revealed three previously described mutations (p. A2215D, p. R277X, and g. IVS30 + 1G > T), and two novel mutations (p. Q2142X and g. IVS46-1G > A). Two known (g. IVS30 + 1G/p. A2215D and p. A2215D/p. R277X) and one novel (p. R277X/g. IVS46-1G > A) compound heterozygous constellations were also identified. Functional analysis indicated deficiency in TG synthesis, reduction of TG secretion, and retention of the mutant TG within the cell, leading to an endoplasmic reticulum storage disease, whereas small amounts of mutant TG were still secreted within the cell system. Conclusion: All studied patients were either homozygous or heterozygous for TG gene mutations. Two novel mutations have been detected, and we show that TG mutation p. A2215D promotes the retention of TG within the endoplasmic reticulum and reduces TG synthesis and secretion, causing mild hypothyroidism. In the presence of sufficient iodine supply, some patients with TG mutations are able to compensate the impaired hormonogenesis and generate thyroid hormone. (J Clin Endocrinol Metab 94: 2938-2944, 2009)

Dietary salt restriction increases plasma lipoprotein and inflammatory marker concentrations in hypertensive patients

Background: Dietary salt restriction has been reported to adversely modify the plasma lipoprotein profile in hypertensive and in normotensive subjects. We investigated the effects of the low sodium intake (LSI) on the plasma lipoprotein profile and on inflammation and thrombosis biomarkers during the fasting and postprandial periods. Methods: Non-obese, non-treated hypertensive adults (n=41) were fed strictly controlled diets. An initial week on a control diet (CID, Na=160 mmol/day) was followed by 3 weeks on LSI (Na=60mmol/day). At admission and on the last day of each period, the 24-h ambulatory blood pressure was monitored and blood was drawn after an overnight fasting period and after a fat-rich test meal. Results: The dietary adherence was confirmed by 24-h urinary sodium excretion. Fasting triglyceride (TG), chylomicron-cholesterol, hsC-reactive protein (CRP), tumor necrosis factor-a (TNF-alpha). interleukin-6 (IL-6) concentrations, renin activity, aldosterone, insulin, and homeostasis model assessment insulin resistance (HOMA-IR) Values were higher, but non-esterified fatty acids (NEFA) were lower on LSI than on CD. For LSI, areas under the curve (AUC) of TG, chylomicron-cholesterol, apoB and the cholesterol/apoB ratio were increased, whereas AUC-NEFA was lowered. LSI did not modify body weight, hematocrit, fasting plasma cholesterol, glucose, adiponectin, leptin, fibrinogen and factor VII (FVII), and AUC of lipoprotein lipase and of lipoprotein remnants. Conclusion: LSI induced alterations in the plasma lipoproteins and in inflammatory markers that are common features of the metabolic syndrome. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

Whose diet has changed?

The same questions about diet were asked in two community-based surveys conducted in the Hunter Region of New South Wales in 1983 and 1994. There were substantial changes in diet over the period; for example, the proportion of respondents who reported using low-fat or skim milk increased from 25 per cent to 51 per cent, the proportion eating meat fewer than five times a week doubled from 21 per cent to 42 per cent and the proportion eating fewer than three eggs per week increased from 55 per cent to 80 per cent. In both surveys, women reported eating a healthier diet than men, and older people and those of higher socioeconomic status reported better diets than younger people or people with less education or lower status occupations. The surprising finding was that over the 11-year period the changes in patterns of food consumption were remarkably similar across all strata of the population. The conclusions are that wide-spread dietary change is possible. However, the changes in the last decade related mainly to reducing the risk of cardiovascular disease; similar behavioural changes to reduce the risk of diet-related cancer are required.

Short-term specialized enteral diet fails to attenuate malnutrition impairment of experimental open wound acute healing

Objective: We assessed the effect of enteral refeeding on the morphology, gene expression, and contraction of acute open wounds in previously malnourished rats using two different enteral diets. Methods: Adult male isogenic Lewis rats divided into two groups (eutrophic, n = 30; and previously malnourished, 12-15% body weight loss, n = 27) were subjected to cutaneous dorsal wounds and gastrostomy. Control rats received a standard oral diet (AIN-93M chow) plus enteral saline solution. Subject rats received chow plus a standard enteral diet or an enteral diet enriched with arginine and antioxidants. On post-trauma days 7 and 14, wound granulation tissue samples were collected for morphologic analysis using hematoxylin and eosin and picrosirius stain or immunohistochemistry slides and real-time polymerase chain reaction for collagen I and III gene expression. Wound contraction was also evaluated by comparing wound images from days 0,7, and 14. Results: Malnourished control rats had increased intensity and duration of wound inflammation, impaired increase of fibroblast cells contingent on post-trauma days 7 to 14, decreased expression of collagen III, and less wound contraction compared with eutrophic control rats. A specialized enteral diet did not improve wound healing of malnourished rats but did promote wound contraction at post-trauma day 7 in eutrophic rats. Conclusion: Short-term enteral refeeding, even with a specialized diet, failed to protect previously wounded malnourished rats from a prolonged inflammatory phase and impaired healing. (C) 2010 Elsevier Inc. All rights reserved.

Human leukemia inhibitory factor upregulates LDL receptors on liver cells and decreases serum cholesterol in the cholesterol-fed rabbit

In a previous study, we found that the cytokine (human) leukemia inhibitory factor (hLIF) significantly reduced plasma cholesterol levels and the accumulation of lipid in aortic tissues of cholesterol-fed rabbits after 4 weeks of treatment. The mechanisms by which this occurs were investigated in the present study. This involved examining the effect of hLIF on (1) the level of plasma cholesterol at different times throughout the 4-week treatment and diet period; (2) smooth muscle cell (SMC) and macrophage-derived foam cell formation in vitro; and (3) LDL receptor expression and uptake in the human hepatoma cell line HepG2. At time zero, an osmotic minipump (2-mL capacity; infusion rate, 2.5 mu L/h; 28 days) containing either hLIF (30 mu g.kg(-1).d(-1)) or saline was inserted into the peritoneal cavity of New Zealand White rabbits (N=24). Rabbits were divided into four groups of six animals each. Group 1 received a normal diet/saline; group 2, a normal diet/hLIF; group 3, a 1% cholesterol diet/saline; and group 4, a 1% cholesterol diet/hLIF. hLIF had no effect on the plasma lipids or artery wall of group 2 rabbits (normal diet). However, in group 4 rabbits, plasma cholesterol levels and the percent surface area of thoracic aorta covered by fatty streaks was decreased by approximate to 30% and 80%, respectively, throughout all stages of the 4-week treatment period. In vitro, hLIF failed to prevent lipoprotein uptake by either SMCs or macrophages (foam cell formation) when the cells were exposed to P-VLDL for 24 hours. In contrast, hLIF (100 ng/mL) added to cultured human hepatoma HepG2 cells induced a twofold or threefold increase in intracellular lipid accumulation in the medium containing 10% lipoprotein-deficient serum or 10% fetal calf serum, respectively. This was accompanied by a significant non-dose-dependent increase in LDL receptor expression in hLIF-treated HepG2 cells incubated with LDL (20 mu g/mL) when compared with controls (P

Neutropenia in antibody-deficient patients under IVIG replacement therapy

Patients with antibody deficiencies are more prone to develop acute neutropenic episodes even during immunoglobulin replacement. The aims of this study were to evaluate the presence of acute neutropenia in 42 patients with primary antibody immunodeficiencies, currently receiving intravenous immunoglobulin (IVIG), and to describe the clinical and laboratory findings during neutropenic episodes. Of all patients, 10 (23.8%) presented acute neutropenia (absolute neutrophil count < 1500 cells/mm(3)) during follow up (mean of 6.4 yr). The absolute neutrophil count ranged from 71 to 1488 cells/mm(3). Neutropenia was not clearly associated with antibiotic prophylactic therapy or immunoglobulin levels, while infections were associated with neutropenia in the majority of episodes. Most acute neutropenia episodes were mild or moderate, except in CVID patients who present more severe neutropenia. Although IVIG may have contributed to reducing the severity of neutropenia, it does not prevent its occurrence in all patients. In conclusion, primary immunodeficient patients, even submitted to IVIG replacement therapy, must be regularly evaluated for neutropenia in order to minimize the risk of infections and its appropriate approach.