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241.
242.
Expression of the AMBP gene transcript and its two protein products,alpha(1)-microglobulin and bikunin,in mouse embryogenesis 总被引:1,自引:0,他引:1
Sánchez D Martínez S Lindqvist A Akerström B Falkenberg C 《Mechanisms of development》2002,117(1-2):293-298
The expression pattern of the alpha(1)-microglobulin/bikunin precursor (AMBP) gene, and its two protein products were studied in mouse embryos of 8.5-15.5 days of embryonic development by in situ hybridization and immunohistochemistry. AMBP mRNA is strongly transcribed in liver parenchyma, pancreas, and intestine epithelium. Sites of weaker expression are the vessels of the umbilical cord, the developing vertebral bodies, and kidney. The alpha(1)-microglobulin and bikunin proteins are accordingly present in developing hepatocytes, pancreas, kidney, and gut. However, additional sites of protein distribution were found that do not correlate to mRNA localization: alpha(1)-microglobulin was found in myocytes and bikunin in cardiac muscle, nervous system microvasculature, and connective tissue. Both proteins were found in brain mesenchyme and meninges. Thus, a restricted expression of the AMBP mRNA in a few organs contrasts to a widespread and unique distribution of each of the two proteins. 相似文献
243.
García Arocena D de Diego Y Oostra BA Willemsen R Mirta Rodriguez M 《Human genetics》2000,106(3):366-369
Fragile X syndrome is the most common cause of hereditary mental retardation. The FMR1 gene, which is involved in fragile X syndrome, contains a polymorphic CGG repeat, which expands in affected patients. Expanding triplet repeats have been shown to be a new type of mutation, termed "dynamic mutation", responsible for more than 12 genetic diseases. These mutations occur as multiple steps rather than as a single event. The first step leads to an unstable allele that then becomes increasingly unstable generally achieving further increases in copy or occasionally contraction. In this report, we describe a fragile X boy with both a hypermethylated full mutation and a deletion of 905 bp encompassing the CGG repeat. The upstream breakpoint is 438 bp 5' to the CGG repeat and the downstream breakpoint is 420 bp 3' of the triplet repeats. The deletion includes the ATG starting codon for translation of the FMR1 gene. This was confirmed by using FMRP immunocytochemistry both on blood smears and hair roots. The deleted region is flanked by a ccgg direct repeat next to the breakpoints; this may have had a critical role in the formation of a secondary DNA structure leading to the deletion. 相似文献
244.
Ana Luiza Fonseca Fortes Furtado Maria do Carmo Calijuri Adriana Sturion Lorenzi Ricardo Yukio Honda Diego Bonaldo Genuário Marli Fátima Fiore 《Hydrobiologia》2009,627(1):195-209
The cyanobacterial population in the Cajati waste stabilization pond system (WSP) from São Paulo State, Brazil was assessed by cell isolation and direct microscope counting techniques. Ten strains, belonging to five genera (Synechococcus, Merismopedia, Leptolyngbya, Limnothrix, and Nostoc), were isolated and identified by morphological and molecular analyses. Morphological identification of the isolated strains was congruent with their phylogenetic analyses based on 16S rDNA gene sequences. Six cyanobacterial genera (Synechocystis, Aphanocapsa, Merismopedia, Lyngbya, Phormidium, and Pseudanabaena) were identified by direct microscope inspection. Both techniques were complementary, since, of the six genera identified by direct microscopic inspection, only Merismopedia was isolated, and the four other isolated genera were not detected by direct inspection. Direct microscope counting of preserved cells showed that cyanobacteria were the dominant members (>90%) of the phytoplankton community during both periods evaluated (summer and autumn). ELISA tests specific for hepatotoxic microcystins gave positive results for six strains (Synechococcus CENA108, Merismopedia CENA106, Leptolyngbya CENA103, Leptolyngbya CENA112, Limnothrix CENA109, and Limnothrix CENA110), and for wastewater samples collected from raw influent (3.70 μg microcystins/l) and treated effluent (3.74 μg microcystins/l) in summer. Our findings indicate that toxic cyanobacteria in WSP systems are of concern, since the treated effluent containing cyanotoxins will be discharged into rivers, irrigation channels, estuaries, or reservoirs, and can affect human and animal health. 相似文献
245.
246.
Martín López De La Torre Diego Bellido Guerrero Josep Vidal Cortada Alfonso Soto González Katherinne García Malpartida Antonio Hernandez-Mijares 《Endocrinología y nutrición》2010,57(10):479-485
IntroductionWaist circumference (WC) and the waist-to-height ratio (WHtR) are anthropometric measures widely used in clinical practice to evaluate visceral fat and the consequent cardiovascular risk. However, risk thresholds should be standardized according to body mass index (BMI).ObjectiveTo determine the distribution of WC and WHtR according to the BMI cut-points currently used to describe overweight and obesity.Materials and methodsWC, WHtR and BMI were measured in 3521 adult patients (>18 years) attended in Endocrinology and Nutrition units.ResultsA total of 20.8% (734 patients) were diabetic. Obesity was found in 82.1% of diabetic patients and in 75% of non-diabetic patients. The WC thresholds proposed by the National Institute of Health (102 cm in men, 88 cm in women), Bray (100 cm in men, 90 cm in women) and the International Diabetes Federation (94 cm in men, 80 cm in women) were exceeded by 92.9%, 94.8% and 98.4% of obese men, 96.8%, 95.5% and 99.7% of obese women, 79.1%, 83.1% and 90% of diabetic men and 95.5%, 81.5% and 97.4% of diabetic women, respectively. Thresholds adapted to the degree of obesity (90, 100, 110 and 125 cm in men and 80, 90, 105 and 115 cm in women for normal BMI, overweight, obesity I and obesity greater than I) were exceeded by 58.4% of obese men, 54.2% of obese women, 57.5% of diabetic men and 60.7% of diabetic women. WC was higher in men, and BMI and the WHtR were higher in women. The WC of diabetic women equalled that of men, and WC, WHtR and BMI were higher in diabetic than in non-diabetic women (p<0.001). WC (p<0.005), WHtR (p<0.001) and BMI (p<0.5) were also higher in diabetic than in non-diabetic men.ConclusionWC and WHtR thresholds by BMI discriminated diabetic and obese patients better than single thresholds, and can be represented graphically by the distribution of percentile ranks of WC and WHtR by BMI.ik 相似文献
247.
Sara Rodríguez-Acebes Nuria Palacios José I Botella-Carretero Nuria Olea Lorena Crespo Roberto Peromingo Diego Gómez-Coronado Miguel A Lasunción Clotilde Vázquez Javier Martínez-Botas 《BMC medical genomics》2010,3(1):1-15
Background
Prevalence of obesity is increasing to pandemic proportions. However, obese subjects differ in insulin resistance, adipokine production and co-morbidities. Based on fasting plasma analysis, obese subjects were grouped as Low Acylation Stimulating protein (ASP) and Triglyceride (TG) (LAT) vs High ASP and TG (HAT). Subcutaneous (SC) and omental (OM) adipose tissues (n = 21) were analysed by microarray, and biologic pathways in lipid metabolism and inflammation were specifically examined.Methods
LAT and HAT groups were matched in age, obesity, insulin, and glucose, and had similar expression of insulin-related genes (InsR, IRS-1). ASP related genes tended to be increased in the HAT group and were correlated (factor B, adipsin, complement C3, p < 0.01 each). Differences between LAT and HAT group were almost exclusively in SC tissue, with little difference in OM tissue. Increased C5L2 (p < 0.01), an ASP receptor, in HAT suggests a compensatory ASP pathway, associated with increased TG storage.Results
HAT adipose tissue demonstrated increased lipid related genes for storage (CD36, DGAT1, DGAT2, SCD1, FASN, and LPL), lipolysis (HSL, CES1, perilipin), fatty acid binding proteins (FABP1, FABP3) and adipocyte differentiation markers (CEBPα, CEBPβ, PPARγ). By contrast, oxidation related genes were decreased (AMPK, UCP1, CPT1, FABP7). HAT subjects had increased anti-inflammatory genes TGFB1, TIMP1, TIMP3, and TIMP4 while proinflammatory PIG7 and MMP2 were also significantly increased; all genes, p < 0.025.Conclusion
Taken together, the profile of C5L2 receptor, ASP gene expression and metabolic factors in adipose tissue from morbidly obese HAT subjects suggests a compensatory response associated with the increased plasma ASP and TG. 相似文献248.
Fine structure of RNA and DNA puffs of Sciara coprophila was studied during late developmental stages of the fourth larval instar. In RNA puffs the predominant structure seen seems to be a diffuse, lampbrush-like thread or threads sectioned in a variety of planes. The thread is composed of filamentous and granular material. Three types of RNA puffs, each with a slightly different morphology, are found. In their development DNA puffs pass through a precise sequence of stages, each with its distinct morphologic and metabolic characteristics. At the initial and final stages, when much of the puff chromatin is in the compacted state, DNA puffs resemble condensed chromosomal bands. In contrast, at stages when most chromatin is diffuse, DNA puffs share many structural characteristics of RNA puffs. Most of the expanded puff area is permeated by lampbrush-like threads composed of fibrils and granules. RNA and DNA puffs were compared with respect to granule size and distribution by means of electron micrographs of known magnification. The results of the statistical analysis show that: 1) The coefficient of variation (C.V.) of the method of measurement falls between 5 and 7%. 2) There is a fluctuation in granule sizes within each puff with a C.V. of 24–26%. 3) The average granule diameter is 238 Å for DNA puffs and 310 Å for RNA puffs; the difference is statistically significant. 4) The variation in mean granule size in a sample of DNA puffs is rather small (C.V. 12%), while the variation in granule size between different RNA puffs is somewhat larger (C.V. 20%). 5) The relative spread of granule sizes in DNA puffs is more restricted than that in RNA puffs. It is evident then that, on the average, DNA puff granules are smaller and more uniform than granules found in RNA puffs. 相似文献
249.
Anna Maria Greco Pasquale Gambardella Raffaella Sticchi Diego D'aponte Pietro De Franciscis 《Chronobiology international》1988,5(3):217-225
Circadian rhythms of serotonin (5HT), its precursors tryptophan (TP) and 5-hydroxy-tryptophan (5HTP) and its acid catabolite 5-hydroxy-indoleacetic acid (5HIAA), were determined in the hypothalamus of control rats and rats which had been treated continuously with subcutaneous imipramine (10 mg/kg/day) for 2 weeks.
Rats were individually housed and entrained to LD12:12. Controls showed the 5HT and TP peaks in the light and dark periods respectively, as reported in the literature, but no inverted correlation (antiphase) between SHT and 5HIAA rhythms.
Imipramine significantly modified circadian rhythm characteristics: the 5HT acrophase was advanced, that of TP and 5HIAA was delayed. Imipramine also significantly increased hypothalamic SHT and TP concentrations. 相似文献
Rats were individually housed and entrained to LD12:12. Controls showed the 5HT and TP peaks in the light and dark periods respectively, as reported in the literature, but no inverted correlation (antiphase) between SHT and 5HIAA rhythms.
Imipramine significantly modified circadian rhythm characteristics: the 5HT acrophase was advanced, that of TP and 5HIAA was delayed. Imipramine also significantly increased hypothalamic SHT and TP concentrations. 相似文献
250.
Vanessa Carregaro José M. Ribeiro Jesus G. Valenzuela Djalma L. Souza-Júnior Diego L. Costa Carlo J. F. Oliveira Laís A. Sacramento Manuela S. L. Nascimento Cristiane M. Milanezi Fernando Q. Cunha Jo?o S. Silva 《PLoS neglected tropical diseases》2015,9(4)