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41.
We have studied the molecular genetics of 27 Brazilian families with ataxia telangiectasia (AT). Five founder effect haplotypes accounted for 55.5% of the families. AT is an autosomal recessive disorder of childhood onset characterized by progressive cerebellar ataxia, ocular apraxia, telangiectasia, immunodeficiency, radiation sensitivity, chromosomal instability, and predisposition to cancer. The ATM gene spans more than 150 kb on chromosome region 11q23.1 and encodes a product of 3056 amino acids. The ATM protein is a member of the phosphatidylinositol 3-kinase (PI-3K) family of proteins and is involved in cell cycle control and DNA repair pathways. DNA was isolated from lymphoblastoid cell lines and haplotyped using four STR markers (D11S1818, NS22, D11S2179, D11S1819) within and flanking the ATM gene; all allele sizes were standardized in advance. In addition to the STR haplotypes, SNP haplotypes were determined using 10 critical polymorphisms. The entire gene was screened sequentially by protein truncation testing (PTT), single strand conformation polymorphism (SSCP), and then denaturing high performance liquid chromatography (dHPLC) to identify the disease-causing mutations. Of the expected 54 mutations, 50 were identified. All mutations but one, led to a truncated or null form of the ATM protein (nonsense, splice site, or frameshift). Five families (18.5%) carried a deletion of 3450nt (from IVS28 to Ex31), making this one of the two most common Brazilian mutations. Mutations were located throughout the entire gene, with no clustering or hotspots. Standardized STR haplotype analysis greatly enhanced the efficiency of mutation screening.  相似文献   
42.
Synthesis and characterization of methacrylate-monofunctionalized crown ether compounds based on derivatives of 2-hydroxymethyl-1,4,7,10,13-pentaoxacyclopentadecane and 4′-hydroxymethyl-1,4,7,10,13-pentaoxabenzocyclopentadecane is described. By differential scanning calorimetry (DSC) and thermooptical analysis (TOA) it is shown that the synthesized compounds and their sodium triflate complexes exhibit columnar mesophases.  相似文献   
43.
The mechanisms by which probiotic bacteria exert their effects on the immune system are not completely understood, but the epithelium may be a crucial player in the orchestration of the effects induced. In a previous work, we observed that some orally administered strains of lactic acid bacteria (LAB) increased the number of immunoglobulin A (IgA)-producing cells in the small intestine without a concomitant increase in the CD4+ T-cell population, indicating that some LAB strains induce clonal expansion only of B cells triggered to produce IgA. The present work aimed to study the cytokines induced by the interaction of probiotic LAB with murine intestinal epithelial cells (IEC) in healthy animals. We focused our investigation mainly on the secretion of interleukin 6 (IL-6) necessary for the clonal expansion of B cells previously observed with probiotic bacteria. The role of Toll-like receptors (TLRs) in such interaction was also addressed. The cytokines released by primary cultures of IEC in animals fed with Lactobacillus casei CRL 431 or Lactobacillus helveticus R389 were determined. Cytokines were also determined in the supernatants of primary cultures of IEC of unfed animals challenged with different concentrations of viable or nonviable lactobacilli and Escherichia coli, previously blocked or not with anti-TLR2 and anti-TLR4. We concluded that the small intestine is the place where a major distinction would occur between probiotic LAB and pathogens. This distinction comprises the type of cytokines released and the magnitude of the response, cutting across the line that separates IL-6 necessary for B-cell differentiation, which was the case with probiotic lactobacilli, from inflammatory levels of IL-6 for pathogens.  相似文献   
44.
SHB is an Src homology 2 domain-containing adapter protein that has been found to be involved in numerous cellular responses. We have generated an Shb knockout mouse. No Shb-/- pups or embryos were obtained on the C57Bl6 background, indicating an early defect as a consequence of Shb- gene inactivation on this genetic background. Breeding heterozygotes for Shb gene inactivation (Shb+/-) on a mixed genetic background (FVB/C57Bl6/129Sv) reveals a distorted transmission ratio of the null allele with reduced numbers of Shb+/+ and Shb-/- animals, but increased number of Shb+/- animals. The Shb- allele is associated with various forms of malformations, explaining the relative reduction in the number of Shb-/- offspring. Shb-/- animals that were born were viable, fertile, and showed no obvious defects. However, Shb+/- female mice ovulated preferentially Shb- oocytes explaining the reduced frequency of Shb+/+ mice. Our study suggests a role of SHB during reproduction and development.  相似文献   
45.
The spread of the plasmid-mediated carbapenem-hydrolyzing oxacillinase OXA-58 was detected in Acinetobacter sp. clinical isolates from southern Europe, the Balkans, and central Turkey. It may contribute significantly to the emergence of carbapenem resistance in Acinetobacter spp., at least in this part of the world.  相似文献   
46.
Bacterial DNA stimulates macrophages, monocytes, B lymphocytes, NK cells, and dendritic cells in a CpG-dependent manner. In this work we demonstrate that bacterial DNA, but not mammalian DNA, induces human neutrophil activation as assessed by L-selectin shedding, CD11b upregulation, and stimulation of cellular shape change, IL-8 secretion, and cell migration. Induction of these responses is not dependent on the presence of unmethylated CpG motifs, as neutrophil stimulatory properties were neither modified by CpG-methylation of bacterial DNA nor reproduced by oligonucleotides bearing CpG motifs. We found that human neutrophils express Toll-like receptor (TLR) 9 mRNA. However, as expected for a CpG-independent mechanism, activation does not involve a TLR9-dependent signaling pathway; neutrophil stimulation was not prevented by immobilization of bacterial DNA or by wortmannin or chloroquine, two agents that inhibit TLR9 signaling. Of note, both single-stranded and double-stranded DNA were able to induce activation, suggesting that neutrophils might be activated by bacterial DNA at inflammatory foci even in the absence of conditions required to induce DNA denaturation. Our findings provide the first evidence that neutrophils might be alerted to the presence of invading bacteria through recognition of its DNA via a novel mechanism not involving CpG motifs.  相似文献   
47.
Maternal and Child Health Journal - To study the relationship between cesarean Delivery (CD) and overweight in preschool children, considering the presence of birth aspects and demographic...  相似文献   
48.
BACKGROUND/OBJECTIVESIncreasing the consumption of vegetables and fruits in Mexico remains a challenge. Promoting sustainable food production systems through schools may be an effective way to educate young people about food and nutrition issues. A study of nutritional education in adolescents, based on the school garden, is necessary in order to evaluate its effects on the consumption of fruits and vegetables among middle- and upper-income segments of the population. The objective of this study was to evaluate the effect of an educational intervention, accompanied by a school garden as an educational teaching tool, to improve vegetable and fruit consumption by Mexican teenagers attending a private middle/high school.SUBJECTS/METHODSTeenagers between 12 and 18 years of age (n = 126) attending a private middle/high school in Queretaro, Mexico participated in a 3-arm, controlled, comparative impact study using a vegetable and fruit consumption frequency questionnaire, food consumption diaries, a psychosocial factor assessment questionnaire of vegetable and fruit consumption, and structured interviews. The participants were randomized into 3 experimental groups: 1) food education + school garden (FE + SG), 2) FE only, and 3) control group (CG).RESULTSThe FE + SG and FE groups significantly increased the frequency and daily intake of vegetables and fruits compared to the CG. The FE + SG group showed greater understanding of, reflection upon, and analysis of the information they received about vegetable and fruit consumption, as well as a greater willingness to include these in their daily diet.CONCLUSIONSFE accompanied by a SG as a teaching tool is more effective at promoting vegetable and fruit consumption than either education alone or control in teenagers in middle-upper income segments of the population.  相似文献   
49.
Childhood obesity and children being overweight has increased recently; although they are multi-causal problems, an unhealthy diet is a critical component. In Mexico, drinking water consumption in children from 9 to 18 years only reaches 30% of total fluid consumption. The aim of our study was to describe the social representations (SR) of drinking water in school-children and parents of two schools in Zapopan, Mexico. Associative free listing was used as an information gathering technique. Schoolchildren aged 8 to 12 years (n = 50) and parents (n = 23) from two elementary schools were selected by a convenience sampling from April to June 2015. A similarity analysis was performed using the co-occurrence index; with this, a similarity graph was obtained. Prototypical analysis was performed to explore the structure of the SR. Three dimensions were described in the children’s SR: a functional dimension related to health and nutrition, a practical dimension that describes the instruments used for its consumption, and a theoretical dimension that specifies the characteristics of water and its relationship with nature. In the parents’ SR, a functional dimension was also found; another dimension was described regarding the integral well-being that drinking water provides. A practical dimension describes the features related to its consumption. The investigation describes the structure of the water SR, which help to contextualize and explain the actions of schoolchildren and their parents regarding drinking water consumption.  相似文献   
50.
Maternal diet has the potential to affect human milk (HM) composition, but very few studies have directly assessed the effect of maternal diets on HM composition. The primary aim of this study was to assess the effect of improving dietary quality in lactating women over 2 weeks on the concentrations of macronutrients and metabolic hormones in HM. The secondary aims were to assess the impact of the dietary intervention on 24 h milk production, maternal body composition and infant growth. Fifteen women completed a 1-week baseline period followed by a 2-week dietary intervention phase targeted towards reducing fat and sugar intake. Maternal anthropometric and body composition and infant growth measurements were performed weekly. Total 24 h milk production was measured before and after the dietary intervention, and HM samples were collected daily. Maternal intakes of energy (−33%), carbohydrate (−22%), sugar (−29%), fat (−54%) and saturated fat (−63%) were significantly reduced during the dietary intervention. HM insulin, leptin and adiponectin concentrations were 10–25% lower at the end of the dietary intervention, but HM concentrations of macronutrients were unaffected. Maternal body weight (−1.8%) and fat mass (−6.3%) were significantly reduced at the end of the dietary intervention, but there were no effects on 24 h milk production or infant growth. These results suggest that reducing maternal energy, carbohydrate, fat and sugar intake over a 2-week period is associated with significant reductions in HM insulin, leptin and adiponectin concentrations. These changes may be secondary to decreases in maternal weight and fat mass. The limited studies to date that have investigated the association between metabolic hormone concentrations in HM and infant growth raise the possibility that the changes in HM composition observed in the current study could impact infant growth and adiposity, but further studies are required to confirm this hypothesis.  相似文献   
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