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991.
Hsu PI Li CN Tseng HH Lai KH Hsu PN Lo GH Lo CC Yeh JJ Ger LP Hsiao M Yamaoka Y Hwang IR Chen A 《Helicobacter》2004,9(6):605-613
BACKGROUND: The host genetic factors that determine the clinical outcomes for Helicobacter pylori-infected individuals remain unclear. AIMS: To elucidate the relations among interleukin-1 locus polymorphisms, and H. pylori infection in the development of duodenal ulcers. MATERIALS AND METHODS: In a case-control study involving 168 control subjects and 147 patients with duodenal ulcer, biallelic polymorphisms of two interleukin-1 loci, IL-1B(-511) and IL-1B(+3954), as well as the penta-allelic variable number of tandem repeats of interleukin-1 receptor antagonist IL-1RN, were genotyped, and the H. pylori states of controls and patients were examined. RESULTS: Helicobacter pylori infection, male gender and the carriage of IL-1RN*2 independently increased the risk of duodenal ulcer with odds ratios of 6.4 (95% confidence interval, 3.7-11.0), 1.9 (95% confidence interval, 1.1-3.4) and 2.7 (95% confidence interval, 1.1-6.8), respectively. Statistical analysis revealed an interaction between IL-1RN*2 and H. pylori infection with the duodenal ulcer risk conferred by the H. pylori infection substantially increased (odds ratios, 22.6; 95% confidence interval, 5.9-86.5) by the carriage of IL-1RN*2. In addition, a synergistic interaction between IL-1RN*2 and blood group O existed. The combined risk of H. pylori infection, the carriage of IL-1RN*2 and blood group O for duodenal ulcer was 27.5 (95% confidence interval, 3.1-243.6). CONCLUSIONS: This work is the first to verify IL-1RN*2 as an independent factor that governs the development of duodenal ulcers. Our data indicate that H. pylori infection and IL-1RN*2 synergistically determine susceptibility to duodenal ulcer. The blood group phenotype is possibly a crucial determinant for the outcome of the impact of an interleukin-1 locus polymorphism on H. pylori-infected individuals. 相似文献
992.
Fernandez S Katsuyama AM Kashiwabara AY Madeira AM Durham AM Gruber A 《FEMS microbiology letters》2004,238(1):183-188
This study reports the development and characterization of 151 sequence characterized amplified region (SCAR) markers for the seven Eimeria species that infect the domestic fowl. From this set, 84 markers are species-specific and 67 present partial specificity. The complete nucleotide sequence was derived for all markers, revealing the presence of micro- and minisatellite repetitive units in 22 SCARs, with up to five distinct repeat units being observed per marker. Only 15 markers showed significant hits in similarity searches against public sequence databases, thus confirming their anonymous and non-coding character. Finally, a relational database of the markers (the Eimeria SCARdb) was developed and made available on the Internet, providing a valuable resource of SCAR markers that can be useful for molecular diagnosis, and also for epizootiological, genetic variability and genome mapping studies. 相似文献
993.
Marques MA Espinosa BJ Xavier da Silveira EK Pessolani MC Chapeaurouge A Perales J Dobos KM Belisle JT Spencer JS Brennan PJ 《Proteomics》2004,4(10):2942-2953
Recently the sequence of the Mycobacterium leprae chromosome, the only known obligate intracellular mycobacterium, was completed. It has a dramatic reduction in functional genes, with a coding capacity of only 49.5%, the lowest one so far observed among bacterial genomes. The leprosy bacillus seems to preserve a minimal set of genes that allows its survival in the host. The identification of genes that are actually expressed by the bacterium is of high significance in the context of mycobacterial pathogenesis. In this current study, a proteomic approach was undertaken to identify the proteins present in the soluble/cytosol and membrane subcellular fractions obtained from armadillo derived M. leprae. Proteins from each fraction were separated by two-dimensional gel electrophoresis (2-DE) and identified by mass spectrometry. A total of 147 protein spots were identified from 2-DE patterns and shown to comprise products of 44 different genes, twenty eight of them corresponding to new proteins. Additionally, two highly basic proteins (with pI >10.0) were isolated by heparin affinity chromatography and identified by N-terminal sequencing. This study constitutes the first application of proteomics to a host-derived Mycobacterium. 相似文献
994.
Growth parameters were surveyed in a sample of 296 Italian children, 6-9 years old, from Cento (Ferrara, Emilia-Romagna). The comparison with children from the same town measured in 1974-75 show changes in some parameters, suggesting an ongoing secular trend. To better understand the observed weight increase and the sex difference, we also evaluated body composition and motricity. The analysis of the present sample is a preliminary part of a longitudinal study dealing with modifications of body composition and motor capacity induced by growth. In our sample the children are growing according to the Italian reference standard. The females present weight, height and Body Mass Index (BMI) values comparable to the 50th centile, while the males present higher values of weight, skinfold thicknesses and BMI. Sex differences in the motor performance were noted. A methodological comparison of obesity assessments based on BMI and percentage of body fat (%F) shows similar conclusions but somewhat different results. 相似文献
995.
996.
Nicola Dalbeth Meaghan E House Gregory D Gamble Bregina Pool Anne Horne Lauren Purvis Angela Stewart Marilyn Merriman Murray Cadzow Amanda Phipps-Green Tony R Merriman 《Arthritis research & therapy》2014,16(1):R34
Introduction
Both genetic variation in ATP-binding cassette sub-family G member 2 (ABCG2) and intake of fructose-containing beverages are major risk factors for hyperuricemia and gout. This study aimed to test the hypothesis that the ABCG2 gout risk allele 141 K promotes the hyperuricaemic response to fructose loading.Methods
Healthy volunteers (n = 74) provided serum and urine samples immediately before and 30, 60, 120 and 180 minutes after ingesting a 64 g fructose solution. Data were analyzed based on the presence or absence of the ABCG2 141 K gout risk allele.Results
The 141 K risk allele was present in 23 participants (31%). Overall, serum urate (SU) concentrations during the fructose load were similar in those with and without the 141 K allele (PSNP = 0.15). However, the 141 K allele was associated with a smaller increase in SU following fructose intake (PSNP <0.0001). Those with the 141 K allele also had a smaller increase in serum glucose following the fructose load (PSNP = 0.002). Higher fractional excretion of uric acid (FEUA) at baseline and throughout the fructose load was observed in those with the 141 K risk allele (PSNP <0.0001). However, the change in FEUA in response to fructose was not different in those with and without the 141 K risk allele (PSNP = 0.39). The 141 K allele effects on serum urate and glucose were more pronounced in Polynesian participants and in those with a body mass index ≥25 kg/m2.Conclusions
In contrast to the predicted responses for a hyperuricemia/gout risk allele, the 141 K allele is associated with smaller increases in SU and higher FEUA following a fructose load. The results suggest that ABCG2 interacts with extra-renal metabolic pathways in a complex manner to regulate SU and gout risk.Clinical Trials Registration
The study was registered by the Australian Clinical Trials Registry (ACTRN12610001036000). 相似文献997.
In this paper we report a new species of Dugesia of the family Dugesiidae from Madagascar, representing the fourth species of freshwater planarian known from this global biodiversity hotspot. In some respects the new species is aberrant, when compared with its congeners, being characterized by a head with smoothly rounded auricles, a peculiar course of the oviducts, including the presence of a common posterior extension, and by the asymmetrical openings of the vasa deferentia at about halfway along the seminal vesicle. Further, it is characterized by a ventral course of the ejaculatory duct with a terminal opening, very long spermiducal vesicles and unstalked cocoons. Its diploid chromosome complement with 18 chromosomes represents an uncommon feature among fissiparous species of Dugesia. 相似文献
998.
Examining the Polymorphisms in the Hypoxia Pathway Genes in Relation to Outcome in Colorectal Cancer
Asan M. S. Haja Mohideen Angela Hyde Jessica Squires Jing Wang Elizabeth Dicks Ban Younghusband Patrick Parfrey Roger Green Sevtap Savas 《PloS one》2014,9(11)
Introduction
Colorectal cancer is a common malignancy. Identification of genetic prognostic markers may help prognostic estimations in colorectal cancer. Genes that regulate response to hypoxia and other genes that are regulated under the hypoxic conditions have been shown to play roles in cancer progression. In this study, we hypothesized that genetic variations in the hypoxia pathway genes were associated with the risk of outcome in colorectal cancer patients.Methods
This study was performed in two phases. In the first phase, 49 SNPs from six hypoxia pathway genes (HIF1A, HIF1B, HIF2A, LOX, MIF and CXCL12) in 272 colorectal cancer patients were analyzed. In the second phase, 77 SNPs from seven hypoxia pathway genes (HIF1A, HIF1B, HIF2A, HIF2B, HIF3A, LOX and CXCL12) were analyzed in an additional cohort of 535 patients. Kaplan Meier, Cox univariate and multivariable regression analyses were performed to analyze the relationship between the SNPs and overall survival (OS), disease free survival (DFS) or disease specific survival (DSS). Since this was a hypothesis-generating study, no correction for multiple testing was applied.Results
In phase I, one SNP (HIF2A rs11125070) was found to be associated with DFS in multivariable analysis; yet association of a proxy polymorphism (HIF2A rs4953342) was not detected in the phase II patient cohort. In phase II, associations of two SNPs (HIF2A rs4953352 and HIF2B rs12593988) were significant in both OS and DFS multivariable analyses. However, association of HIF2A rs4953352 was not replicated in the phase I cohort using a proxy SNP (HIF2A rs6706003).Conclusion
Overall, our study did not find a convincing evidence of association of the investigated polymorphisms with the disease outcomes in colorectal cancer. 相似文献999.
Angela Brieger Boris Adryan Fabian Wolpert Sandra Passmann Stefan Zeuzem Jörg Trojan 《Proteomics》2010,10(18):3343-3355
The involvement of MLH1 in several mismatch repair‐independent cellular processes has been reported. In an attempt to gain further insight into the protein's cellular functions, we screened for novel interacting partners of MLH1 utilizing a bacterial two‐hybrid system. Numerous unknown interacting proteins were identified, suggesting novel biological roles of MLH1. The network of MLH1 and its partner proteins involves a multitude of cellular processes. Integration of our data with the “General Repository for Interaction Datasets” highlighted that MLH1 exhibits relationships to three interacting pairs of proteins involved in cytoskeletal and filament organization: Thymosin β 4 and Actin γ, Cathepsin B and Annexin A2 as well as Spectrin α and Desmin. Coimmunoprecipitation and colocalization experiments validated the interaction of MLH1 with these proteins. Differential mRNA levels of many of the identified proteins, detected by microarray analysis comparing MLH1‐deficient and ‐proficient cell lines, support the assumed interplay of MLH1 and the identified candidate proteins. By siRNA knock down of MLH1, we demonstrated the functional impact of MLH1–Actin interaction on filament organization and propose that dysregulation of MLH1 plays an essential role in cytoskeleton dynamics. Our data suggest novel roles of MLH1 in cellular organization and colorectal cancerogenesis. 相似文献
1000.
Angela Chambery Valeria Severino Antimo Di Maro Antimo D’Aniello Menotti Ruvo Augusto Parente 《Amino acids》2010,38(4):1031-1041
Thyrotropin-releasing hormone (TRH) is involved in a wide range of biological responses. It has a central role in the endocrine
system and regulates several neurobiological activities. In the present study, a rapid, sensitive and selective liquid chromatography–mass
spectrometry method for the identification and quantification of TRH has been developed. The methodology takes advantage of
the specificity of the selected-ion monitoring acquisition mode with a limit of detection of 1 fmol. Furthermore, the MS/MS
fragmentation pattern of TRH has been investigated to develop a selected reaction monitoring (SRM) method that allows the
detection of a specific b2 product ion at m/z 249.1, corresponding to the N-terminus dipeptide pyroglutamic acid–histidine. The method has been tested on rat hypothalami to evaluate its suitability
for the detection within very complex biological samples. 相似文献