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71.
目的分析抗胰岛素抗体(IAA)、抗胰岛细胞抗体(ICA)和抗谷氨酸脱羧酶抗体(GADA)在患者中的分布情况及实验室指标的变化,探讨三种糖尿病相关抗体对疾病发生、发展变化的预示价值,为疾病治疗提供依据。方法分析2008-2018年在四川大学华西医院联合检测了IAA、ICA和GADA三种抗体患者的相关信息。将抗体阳性患者分为3个不同的年龄组(<40岁、40~59岁、>59岁),比较抗体检测结果组合在各年龄组间分布差异,分析抗体阳性患者疾病分布情况。以抗体阳性分组,分析三种抗体单项阳性组(单阳组)患者实验室指标检测结果的差异。结果三种抗体在不同年龄组间的分布差异无统计学意义(P>0.05);糖尿病患者人群IAA抗体单项阳性占65.08%;三种抗体主要存在于糖尿病患者中(占92.03%),其他疾病(如癌症、低血糖、系统性红斑狼疮)患者也可出现。碱性磷酸酶在IAA单阳组中的水平显著低于ICA单阳组(P<0.05);尿酸和肌酐在IAA单阳组中的水平显著高于GADA单阳组(P<0.05);球蛋白和肾小球滤过率在IAA单阳组水平显著低于GADA单阳组(P<0.05);空腹胰岛素在IAA单阳组水平显著高于ICA和GADA单阳组(P<0.05)。结论IAA、ICA和GADA三种抗体在各年龄组分布相近。IAA可作为糖尿病抗体检测的首选指标,IAA阳性糖尿病患者更应该注意其并发肾功能损害的风险。 相似文献
72.
Disruption of intestinal motility by a calcium channel-stimulating autoantibody in type 1 diabetes 总被引:4,自引:0,他引:4
BACKGROUND & AIMS: Autonomic neuropathy, including gastrointestinal dysfunction, is a common complication of type 1 diabetes; however, its cause is uncertain. This study aimed to test whether functional autoantibodies cause the gastrointestinal dysfunction. METHODS: We used isolated mouse colon undergoing colonic migrating motor complex (MMC) activity to test for autoantibodies that disrupt colonic motility. Purified immunoglobulin G (IgG) from patients with type 1 diabetes or from controls was tested either in vitro or after passive transfer. Pharmacological studies of the interaction between the IgG and L-type calcium channel activator (Bay K8644) and inhibitors (nicardipine and verapamil) were performed. The effect of IgG on nerve-evoked contraction of the vas deferens longitudinal smooth muscle was also assessed. RESULTS: MMC activity was disrupted by IgG (0.2 mg/mL) from 8 of 16 patients with type 1 diabetes but not by control IgG. Passive transfer of diabetic IgG to mice also disrupted MMCs, showing access to the antigen in vivo. The acute effect of the autoantibody was mimicked by the dihydropyridine agonist, Bay K8644 (2-10 nmol/L), and both Bay K8644 and the autoantibody competitively inhibited the effect on MMC contraction of the dihydropyridine antagonist, nicardipine. Diabetic IgG, but not control IgG, altered the nerve-evoked contractile activity of vas deferens smooth muscle effects mimicked by Bay K8644. CONCLUSIONS: A novel functional autoantibody that activates smooth muscle L-type calcium channels at the dihydropyridine binding site is produced specifically by patients with type 1 diabetes and may mediate gastrointestinal and autonomic dysfunction in these patients. 相似文献
73.
Veldic M Guidotti A Maloku E Davis JM Costa E 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(6):2152-2157
Cortical DNA-methyltransferase 1 (DNMT1) is preferentially expressed in interneurons secreting GABA where it very likely contributes to promoter CpG island hypermethylation, thus causing a down-regulation of promoter functions. To consolidate and expand on previous findings that, in the cortex of schizophrenia (SZ) brains, glutamic acid decarboxylase 67 (GAD67) expression is down-regulated whereas that of DNMT1 is up-regulated, we studied both parameters in Brodmann's area (BA) 9 from the McLean 66 Cohort Collection (Harvard Brain Tissue Resource Center, Belmont, MA). In BA9 of SZ and bipolar disorder patients with psychosis, DNMT1 mRNA and protein expression preferentially increases in layer I, II, and IV interneurons, and this increase is paralleled by a decreased number of GAD67 mRNA-positive neurons. The increase in DNMT1 and the decrease in GAD67-expressing neurons were unrelated to postmortem interval, pH, RNA quality, or to the presence, dose, or duration of antipsychotic (APS) medication, with the exception of a subgroup of SZ patients treated with a combination of valproate and APS in which the expression of DNMT1 failed to change. The DNMT1 increase and the GAD67 decrease in BA9 interneurons are significant features of SZ and bipolar disorder with psychosis. Interestingly, the DNMT1 increase failed to occur when patients with psychosis received a combination of valproate and APS treatment but not APS monotherapy. 相似文献
74.
Peter R. Dodd Wendy E. J. Watson Murray M. Morrison Graham A. R. Johnston A. Ian Smith Anita Ruwoldt Ronald S. Walls 《Metabolic brain disease》1991,6(4):213-224
A factor from mammalian and human brain, which inhibits the rate of migration of leukocytes obtained from sufferers from Huntington disease (Walls and Ruwoldt, 1984), inhibited the specific binding of the neurotoxin [3H]kainic acid to rat brain synaptic membranes. The factor was present in sucrose-particulate but not in soluble fractions from rat sub-cortical tissue, and was destroyed by tryptic digestion. Whereas an ammonium sulfate fraction of direct saline extracts of brain (Walls and Ruwoldt, 1984) gave poor chromatography on HPLC, prior separation of a sucrose-particulate fraction resulted in much improved chromatography. There was a good concordance between leukocyte migration inhibitory activity and [3H]kainic acid binding inhibitory activity. The factor may be an endogenous modulator of the kainic acid subset of receptors for the excitatory neurotransmitter glutamic acid. 相似文献
75.
目的 测定我国恶性疟原虫海南株 (FCC1/ HN)谷氨酸富集蛋白 (GARP)、丝氨酸重复抗原 (SERA)和裂殖子表面蛋白 1(MSA1)基因序列 ,并进行序列分析。 方法 采用 PCR技术从恶性疟原虫 FCC1/ HN株基因组 DNA中扩增 GARP、SERA和 MSA1基因片段 ,分别插入到测序载体上进行测序。应用 DNAstar软件辅助分析 3种抗原基因的结构及 3种抗原在不同恶性疟原虫株间的分化情况。 结果 恶性疟原虫 FCC1/ HN株 GARP基因全长 2 2 6 3bp,编码6 82个氨基酸残基 ,谷氨酸占 2 3.6 1% ,包含 5个典型的氨基酸重复序列 ;SERA基因全长 344 8bp,编码 995个氨基酸残基 ,丝氨酸含量为 10 .6 5 % ,包含 1个连续 32个丝氨酸 (S)残基的序列 ;MSA1基因全长 5 0 85 bp,编码 16 94个氨基酸残基 ,MSA1的氨基酸序列符合 MAD2 0型特征。恶性疟原虫 FCC1/ HN株与 3D7、FC2 7株 GARP的序列差异主要集中于 C-末端 ;FCC1/ HN株与 FCR3、3D7、FCBR、Hondulas- 1株 SERA的序列差异主要集中于 N-端。FCC1/ HN株与MAD2 0、3D7、HN1、HN2、FC2 7、RO- 71、RO- 33、CAMP和 Palo- alto株 MSA1的同源性高 ,K1和 WEL L COME株 MSA1的同源性高 ,各分离株 MSA1的序列差异主要处于第 2至 16分区。 结论 了解了恶性疟原虫 FCC1/ HN株 GARP、SERA和 MSA1的 相似文献
76.
Objectives Acidosis has an inhibitory effect on the inactivation of Kv1.4 ΔN channel through the position H508. So in order to show the effects of glutamic acid on the mutant Kv 1.4 channel that lacks N-type inactivation (Kv1.4 Δ2-146), we studied in the expression system of the Xenopus oocytes. Methods The two-electrode voltage-clamp technique (TEV) was used to record the currents. Results Acidosis increased fKv1.4 Δ2-146 C-type inactivation. After application of glutamic acid (1 mmol/L) to Kv1.4 Δ2-146 increased C-type inactivation further, changed inactivation time constants from (2.02 ± 0.39 s ) to (1.71 ± 0.23 s) (P〈 0.05) at +50mv, and shifted the steady-state inactivation curves of Kv1.4 ΔN to positive potential, which was from (-44.30 ± 0.59 mV) to (-39.88 ± 0.29 mV)(P〈0.05). and slowed the rate of recovery from inactivation, which was from (1.64 ± 0.19 s) to (1.91 ± 0.23 s)(P〈 0.05). Conclusions Together, these results suggest that 1 mmol/L glutamic acid accelerates the C-type inactivation of Kv1.4 ΔN in pH 6.8. 相似文献
77.
Jeffrey R. Stout Abbie E. Smith-Ryan David H. Fukuda Kristina L. Kendall Jordan R. Moon Jay R. Hoffman Jacob M. Wilson Jeffery S. Oliver Vikkie A. Mustad 《Experimental gerontology》2013
Background
Evidence suggests CaHMB may impact muscle mass and/or strength in older adults, yet no long-term studies have compared its effectiveness in sedentary and resistance training conditions. The purpose of this study was to evaluate the effects of 24 weeks of CaHMB supplementation and resistance training (3 d wk− 1) or CaHMB supplementation only in ≥ 65 yr old adults.Methods
This double-blinded, placebo-controlled, trial occurred in two phases under ad libitum conditions. Phase I consisted of two non-exercise groups: (a) placebo and (b) 3 g CaHMB consumed twice daily. Phase II consisted of two resistance exercise groups: (a) placebo and resistance exercise and (b) 3 g CaHMB consumed twice daily and resistance exercise (RE). Strength and functionality were assessed in both phases with isokinetic leg extension and flexion at 60°·s− 1 and 180°·s− 1 (LE60, LF60, LE180, LF180), hand grip strength (HG) and get-up-and-go (GUG). Dual X-Ray Absorptiometry (DXA) was used to measure arm, leg, and total body lean mass (LM) as well as total fat mass (FM). Muscle Quality was measured for arm (MQHG = HG/arm LM) and Leg (MQ60 = LE60/leg LM) (MQ180 = LE180/leg LM).Results
At 24 weeks of Phase I, change in LE60 (+ 8.8%) and MQ180 (+ 20.8%) for CaHMB was significantly (p < 0.05) greater than that for placebo group. Additionally, only CaHMB showed significant (p < 0.05) improvements in total LM (2.2%), leg LM (2.1%), and LE180 (+ 17.3%), though no treatment effect was observed. Phase II demonstrated that RE significantly improved total LM (4.3%), LE60 (22.8%), LE180 (21.4%), HG (9.8%), and GUG (10.2%) with no difference between treatment groups. At week 24, only CaHMB group significantly improved FM (− 3.8%) and MQHG (7.3%); however there was no treatment main effect for these variables.Conclusion
CaHMB improved strength and MQ without RE. Further, RE is an effective intervention for improving all measures of body composition and functionality. 相似文献78.
《中华老年心脑血管病杂志》2013,15(1):57-59
目的探讨血清谷氨酸与缺血性脑卒中早期进展的关系。方法选择缺血性脑卒中患者120例,分为进展性脑卒中组60例,非进展性脑卒中组60例。另选择同期住院非脑卒中患者30例作为对照组。采用高效液相色谱法检测发病1、3、7d的谷氨酸水平。结果与对照组比较,进展性脑卒中组和非进展性脑卒中组1、3、7d血清谷氨酸水平明显升高,差异有统计学意义(P<0.05)。与非进展性脑卒中组比较,进展性脑卒中组发病1、3d血清谷氨酸水平明显升高[(105.8±13.3)μmol/L vs(96.7±11.3)μmol/L,(116.0±13.3)μmol/L vs(101.1±11.2)μmol/L,P<0.05]。结论在缺血损伤早期,血清谷氨酸水平变化可预测缺血性脑卒中的进展。 相似文献
79.
Side reactions in peptide synthesis indicate steps needing improvement as well as opportunities for structural diversification in combinatorial design. Among the side reactions observed in this study, transesterification of Boc-Glu(OBzl) occurred in TMAH-catalyzed resin attachment, leading to Boc-DKKREE(OMe) in solid-phase synthesis of Boc-DKKREE. Acetylation of Boc-Arg(NO2)-resin occurred during resin capping with Ac2O/Et3N, leading to GPR(Ac) in GPR synthesis. His- and Lys-modification occurred during GHRPLDKKREE cleavage from resin by Pd(OAc)2-catalyzed hydrogenation in DMF. To verify these side reactions, model experiments were performed, which indicated rapid transesterification of Boc-Glu(OBz1) in methyl. isopropyl, or tert-butyl alcohol into the corresponding ester by TMAH, but not by Cs. This TMAH ability was used to devise a convenient procedure for peptide cleavage. TLC studies of acetylation showed that both Boc-Arg(NO2) and Boc-Arg(Tos) were stable to Ac-Im treatment, but were modified by Ac2O/Et3N. Since transfer hydrogenation of Boc-His(Bzl) and Boc-Lys(Z) in HCOOH or ammonium formate did not generate the formylated side-products of catalytic hydrogenation, DMF and not its decomposed product, HCOOH, appeared involved in side-chain modification. Elimination of the side reactions, by using Cs-derived Boc-Glu(OBzl)-resin for peptide synthesis and catalytic hydrogenation in NMP-HOPr for peptide cleavage. increased the GHRPLDKKREE yield by 1/3. On the other hand, the side reactions provided modified peptides, whose bioassays revealed different importance of the modified side-chains. © Munksgaard 1996. 相似文献
80.
谷氨酸对伏隔核痛反应神经元放电的影响 总被引:2,自引:0,他引:2
目的:研究脑室内注入谷氨酸(Glu)对伏隔核(NAcc)痛反应神经元放电的影响。方法:细胞外记录神经元放电。结果:(1)伤害性刺激可使NAcc内痛兴奋神经元(PEN)电活动增加,使痛抑制神经元(PIN)电活动减少。(2)脑室内注入Glu可命名NAcc内PEN诱发放电频率增加,潜伏期缩短;使PIN诱发放电频率减少,抑制时程延长。结论:脑室注入Glu可使NAcc内痛反应神经元对伤害性刺激的反应加强,表现出Glu易化疼痛效应。 相似文献