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61.
62.
Association of tumor necrosis factor polymorphism with primary sclerosing cholangitis 总被引:5,自引:0,他引:5
BACKGROUND/AIMS: Primary sclerosing cholangitis is associated with the HLA haplotypes A1-B8-DRB3*0101-DRB1*0301-DQA1*0501-DQB1*0201 and DRB3*0101-DRB1*1301-DQA1*0103-DQB1* 0603. However, the interpretation of these genetic associations is controversial. One explanation may be that HLA-encoded susceptibility is due to other genes carried on these haplotypes such as the HLA class III tumor necrosis factor genes. The aim of the study was to investigate tumor necrosis factor genetics in a large series of well-defined patients. METHODS: One hundred and ten HLA genotyped patients and 126 control subjects were studied by polymerase chain reaction genotyping for 3 different tumor necrosis factor gene polymorphisms: -308, -238 and an Ncol restriction fragment length polymorphism in the lymphotoxin alpha gene. RESULTS: Overall, 58% of patients had the TNF2 allele, compared with 29% of controls, p(c) = 0.0001. No association was found with either of the other tumor necrosis factor polymorphisms examined. TNF2 was significantly increased in the presence of B8 and DRB3*0101 only, and was independent of DRB1*0301 (p(c)<0.04). The associations with B8 and TNF2 were stronger than the associations with any of the HLA class II alleles examined. CONCLUSION: HLA-encoded genetic susceptibility to primary sclerosing cholangitis may be determined by polymorphism within the HLA class III region, in particular with the TNF2 allele. 相似文献
63.
Isolated rat liver nuclei show a substantial amount of T3 receptor release to the medium during in vitro incubation. This has been shown to be a general feature of nuclei compared after several methods of isolation and incubation. About 50% of nuclear receptors are released to the medium when incubated in sucrose-MgCl2-Tris, pH 7.85, for 2 h at 20 C.DNA, histones, and non-histone proteins (NHP) are also released. CaCl2 inhibits about 90% of the release of DNA and histones, but has less effect on inhibiting leakage of NHP and nuclear T3-binding protein (NTBP). The highest leakage for each fraction was found when incubating nuclei in the presence of EDTA. The receptor released to the medium has an affinity virtually identical to the receptor remaining in the nuclei. At least 1 mM dithiothreitol is needed to avoid degradation of the receptor. The NTBP has a sedimentation constant of 4.5 S when studied in low ionic strength gradients. Increasing KCl concentration decreases progressively its sedimentation constant, and in gradients containing 0.4 M KCl the receptor sediments as a single peak of 3.4 S. Since release of receptor to incubation medium decreases free T3 concentration, it must be taken into account in calculating receptor affinity. Total nuclear capacity in vitro is obviously underestimated, unless receptor released to medium is measured. Receptor exchange between cytosol and nucleus may be of physiologic significance. 相似文献
64.
Interactions between vascular endothelial cells and blood platelets have been investigated using a model microcirculation consisting of microcarrier beads colonized with human umbilical vein endothelial cells (HUVECs) and perfused with washed platelet suspensions. To simulate the effects of endothelial desquamation and exposure of subendothelium, fibrillar collagen in suspension was coinjected with the platelets. In this model, neither the passage of platelets alone nor collagen alone stimulated prostacyclin (PGI2) production by the HUVECs. Platelets activated by coinjection with collagen released thromboxane A2 (TXA2), and this was associated with the simultaneous production of PGI2 by the HUVECs. By means of double-isotope experiments with [3H]arachidonic acid (AA) incorporated into platelets and [14C]-AA into HUVECs, it was shown that all the PGI2 generated was derived from platelet AA and/or endoperoxides. This interpretation was strengthened by the finding that PGI2 production was not prevented by treatment of HUVECs with indomethacin followed by perfusion with collagen-stimulated platelets. AA metabolites in double-isotope label experiments were further characterized by reverse-phase chromatography, and it was shown that both cyclooxygenase and lipoxygenase products of the HUVECs were derived from platelet membrane lipid. Thrombin regularly produced transient PGI2 release, but showed rapid tachyphylaxis. Platelet-derived compounds including ADP, ATP, and platelet-activating factor (PAF) did not produce PGI2 release by HUVECs in this system. Thus, the transfer of AA and metabolites from collagen- stimulated platelets is likely to be the mechanism for PGI2 production in the context of minor degrees of endothelial desquamation. 相似文献
65.
Blanca Lynne Suárez María Inés álvarez Matilde de Bernal Andrés Collazos 《Colombia Médica》2013,44(1):26-30
Objective:
To determine the prevalence of Candida species and to study factors associated to oral cavity colonization in patients with type 2 diabetes mellitus.Methods:
A total of 107 diabetics were classified into controlled and uncontrolled according to glycosylated hemoglobin values. Each patient was assessed for stimulated salivary flow rates, pH, and an oral rinse to search for yeast. The study also determined the state of oral health via Klein and Palmer CPO indexes for permanent dentition, dental plaque by O''Leary, and a periodontal chart.Results:
We found yeasts in 74.8% of the patients. A total of 36 of the 52 subjects with controlled diabetes presented yeasts and 44 in the uncontrolled; no significant differences (p = 0.2) were noted among the presence of yeasts and the control of blood glucose. The largest number of isolates corresponded to C. albicans, followed by C. parapsilosis. Uncontrolled individuals presented a significantly higher percentage of yeast different from C. albicans (p = 0.049).Conclusions:
We found a high percentage of Candida colonization and uncontrolled individuals had greater diversity of species. The wide range of CFU/mL found both in patients with oral candidiasis, as well as in those without it did not permit distinguishing between colonization and disease. We only found association between isolation of yeasts and the low rate of salivary flow. 相似文献66.
Dr. William W. Dressler Ph.D. Ms. Henrietta Bernal R.N. 《Behavioral medicine (Washington, D.C.)》2013,39(3):32-38
Abstract In this study, the acculturative stress experienced by Puerto Rican migrants to the urban U.S. is examined. Acculturative stress is defined as length of residence in a novel cultural environment while lacking psychosocial resources to support adaptation to that environment. In a sample of 67 patients seen in a public health nursing agency, it was found that acculturative stress was associated with poorer health status, more behavioral problems, and higher levels of ethnomedical belief. The implications of these results for research on stress and adaptation are discussed. 相似文献
67.
N Senst M Llacuachaqui J Lubinski H Lynch S Armel S Neuhausen P Ghadirian P Sun SA Narod 《Clinical genetics》2013,84(1):43-46
The objective is to estimate the risk of breast cancer in women who carry a deleterious BRCA1 or BRCA2 mutation, according to parental origin of mutation. We conducted a cohort study of women with a BRCA1 mutation (n = 1523) or BRCA2 mutation (n = 369) who had not been diagnosed with breast or ovarian cancer. For each woman, the pedigree was reviewed and the origin of the mutation was assigned as probable paternal or maternal. The hazard ratio (HR) for developing breast cancer in the follow‐up period was estimated for women with a paternal mutation compared to a maternal mutation. The risk of breast cancer was modestly higher in women with a paternal BRCA1 mutation compared to women with a maternal BRCA1 mutation (HR = 1.46; 95% CI = 0.99–2.16) but the difference was not significant (p = 0.06). The parental mutation origin did not affect the risk in women with a BRCA2 mutation. Our results are consistent with the hypothesis that there is an increased risk of breast cancer among women with a paternally inherited BRCA1 mutation compared to a maternally inherited mutation. However, the data are not sufficiently compelling to justify different screening recommendations for the two subgroups. 相似文献
68.
MB Delatycki M Wolthuizen MA Aitken C Hickerton SA Metcalfe KJ Allen 《Clinical genetics》2013,84(3):286-289
Hereditary hemochromatosis (HH) is a common preventable disorder of iron overload that can result in liver cirrhosis and reduced lifespan. Most HH is due to homozygosity for the HFE p.C282Y substitution. We conducted a study of screening for p.C282Y in high schools where p.C282Y heterozygotes (CY) individuals were informed of their genotype by letter. We studied whether these individuals understood the implications of their genotype, whether this resulted in anxiety or reduced health perception and whether cascade testing was higher in families of CY than wild‐type homozygous (CC) individuals. We found 586 of 5757 (1 in 10) screened individuals were CY. One month after receiving their result, 83% correctly answered that they have one copy of p.C282Y. There was no adverse change in anxiety or health perception from prior to screening to 1 month after receiving results. Significantly more family members of CY individuals than CC individuals were informed about HH and had testing for HH. In conclusion, we found that informing CY individuals of their genotype does not increase anxiety and the implications are generally well understood. This leads to cascade testing in a minority of families. CY individuals should be informed of their genetic status when identified by population screening. 相似文献
69.
Escandriolo Nackauzi Jorge Repossi Gastón Bernal Claudio Actis Adriana Gallará Raquel 《Clinical oral investigations》2020,24(11):4123-4131
Clinical Oral Investigations - The aim of this study was to analyze the influence of dietary fatty acids (FAs) and the time elapsed from their intake on FA tissue profile of rat submandibular gland... 相似文献
70.
目的:对蒙药苏格木勒-3水提物进行化学成分研究,构建较为全面的化学成分谱,为苏格木勒-3水提物有效物质基础研究奠定基础。方法:采用超高液相色谱串联四级杆飞行时间质谱(UPLC-Q-TOF-MS)技术,使用ESI离子源,通过mzCloud与mzVoult软件以及质谱裂解规律,并结合对照品及相关文献资料比对进行定性分析。结果:经过分析,从蒙药苏格木勒-3水提物中共鉴定出42个成分,主要包括氨基酸、酚酸类、黄酮类、内酯类、生物碱类及其他类等6类成分,并对各成分的药材来源进行归属。结论:本研究全面、快速、准确地分析了蒙药苏格木勒-3水提物的化学成分,为其药效物质基础和质量控制等研究奠定了基础。 相似文献