Increased Levels of AIM2 and Circulating Mitochondrial DNA in Type 2 Diabetes

Background: Chronic inflammation has critical role in Type 2 diabetes (T2D), in which IL-1β contributes in insulin resistance and beta cell dysfunction. The activation of NLRP3 and AIM2 by endogens ligands, such as mtDNA can lead to the release of active form of IL-1β. Objective: To evaluate AIM2 expression and activation as well as circulating mtDNA levels in T2D patients. Methods: AIM2 expression was analyzed by flow cytometry, it’s activity was assessed by measuring in vitro release of IL-1β induced by Poly (dA:dT), and mtDNA copy number was determined by quantitative real-time polymerase chain reaction. Results: Increased percent of AIM2+ cells were detected in monocytes from patients with T2D. Moreover, increased levels of IL-1β in monocytes cultures from T2D patients compared to healthy controls were observed. Also, association between AIM2+ cells and hyperglycemia (r=0.4385, P=0.0095) and triglycerides levels (r=0.5112, P=0.002) and waist-hip ratio (r=0.4710, P=0.0049) were detected. Likewise, the mtDNA copy number was augmented in T2D patients compared to control group. The mtDNA copies number was associated with body mass index (r=0.4231, P=0.0008) and TNF-α levels (r=0.5231, P=0.0005). In addition, increased levels of IL-12p70, TNF-a, IL-10, IL-6, IL-8 and IL-1β were detected in a serum from T2D patients. Conclusion: These results suggest the involvement of AIM2 and mtDNA in the inflammatory process seen in T2D.     

RT—PCR检测急性早幼粒细胞白血病微小残留病

用逆转录－聚合酶链反应（ＲＴ－ＰＣＲ）技术，检测了２２列早幼粒细胞白血病（ＡＰＬ）缓解患者ＰＭＬ－ＲＡＲα融合基因。结果显示性率在缓解时间１年内（１１／１４）较１￣２年（２／５）及３年以上（０／３）明显高，持续阳性多预示着复发。认为检测ＰＭＬ－ＲＡＲα融合基因，可作为监测ＡＰＬ病情转归、评价疗效的重要指标。     

The Effect of Somatostatin Analogue SMS 201—995 on Serotonin Levels in the Medium of Primary Carcinoid Cell Cultures

Carcinoid cell cultures were established from primary tumours and liver and mesenteric metastases. The cells continued to produce serotonin for up to 6 months. Cells from different tumours showed different properties. In most wells carcinoid cells grew on a layer of fibroblasts. The tendency to co-culture seemed to be less marked in cells from liver biopsy specimens. The amount of serotonin decreased to 63% 300 min after addition of the somatostatin analogue SMS 201–995 (SMS) to the culture, compared with controls (p < 0.05; n = 10). This decrease was observed up until 12 days, when SMS was added at each change of medium (p < 0.005; n = 8). In the first 10 min, however, SMS induced an increase in serotonin concentration (p < 0.005; n = 11). This effect may be related to other, immediate stimulatory effects of SMS seen in other cell lines originating from neural ridge-derived tissue. We believe it is important to elucidate the properties of individual tumours, as choice of therapy may vary between patients with the same diagnosis. We have described a method to obtain such information within a couple of days, before a definite treatment is selected.     

Cleavage of Replicating Forms of Mitochondrial DNA by EcoRI Endonuclease

Digestion of mouse L cell mitochondrial DNA with EcoRI restriction endonuclease produces two linear duplex fragments comprising 86.3 +/- 2.0% and 14.2 +/- 1.0% of the circular genome length (16,000 +/- 470 nucleotide pairs). Digestion of human HeLa cell mitochondrial DNA with EcoRI produces three linear duplex fragments comprising 49.2 +/- 1.0%, 44.4 +/- 0.9%, and 6.4 +/- 0.4% of the circular genome length (16,590 +/- 710 nucleotide pairs). These fragments are shown to be generated by cleavage in unique regions of the mouse and human mitochondrial DNAs. An electron microscopic analysis of partially replicated molecules cleaved by EcoRI establishes a unidirectional mode of DNA replication for L cell mitochondrial DNA. The origin for DNA replication is located on the larger EcoRI fragment at a position that is 1,890 +/- 250 nucleotide pairs (11.8 +/- 1.2% of the circular genome length) from the proximal restriction site. Replication proceeds unidirectionally away from this restriction site throughout the length of the larger EcoRI fragment. Analysis of L cell, D-loop mitochondrial DNA cleaved by EcoRI indicates that a unique sequence is synthesized in formation of the D-loop in these nonreplicating molecules. The origin of D-loop synthesis is located on the larger EcoRI fragment at a position 1,760 +/- 180 nucleotide pairs (11.0 +/- 1.1% of the circular genome length) from the proximal restriction site and is, therefore, the origin for unidirectional displacement replication.     

Nucleoside Analogue Can Improve the Long-Term Prognosis of Patients with Hepatitis B Virus Infection-Associated Acute on Chronic Liver Failure

Background  

The prognosis of patients with hepatitis B virus (HBV)-associated acute on chronic liver failure (ACLF) is extremely poor.     

Mitochondrial DNA and the origins of the domestic horse

The place and date of the domestication of the horse has long been a matter for debate among archaeologists. To determine whether horses were domesticated from one or several ancestral horse populations, we sequenced the mitochondrial D-loop for 318 horses from 25 oriental and European breeds, including American mustangs. Adding these sequences to previously published data, the total comes to 652, the largest currently available database. From these sequences, a phylogenetic network was constructed that showed that most of the 93 different mitochondrial (mt)DNA types grouped into 17 distinct phylogenetic clusters. Several of the clusters correspond to breeds and/or geographic areas, notably cluster A2, which is specific to Przewalski's horses, cluster C1, which is distinctive for northern European ponies, and cluster D1, which is well represented in Iberian and northwest African breeds. A consideration of the horse mtDNA mutation rate together with the archaeological timeframe for domestication requires at least 77 successfully breeding mares recruited from the wild. The extensive genetic diversity of these 77 ancestral mares leads us to conclude that several distinct horse populations were involved in the domestication of the horse.     

Isolation of Saccharomyces cerevisiae Mitochondrial Formyltetrahydrofolic Acid:Methionyl-tRNA Transformylase and the Hybridization of Mitochondrial fMet-tRNA with Mitochondrial DNA

Formyltetrahydrofolic acid:methionyl-tRNA transformylase was isolated from Saccharomyces cerevisiae mitochondria and used to prepare yeast mitochondrial [(3)H]formylmethionyl-tRNA. This fMet-tRNA hybridizes with mitochondrial DNA but not with yeast nuclear or E. coli DNA. Unlabeled mitochondrial, but not extramitochondrial, tRNA competes in this reaction. tRNA was eluted from the hybrid and found to contain the label almost exclusively in fMet-tRNA. Yeast cytoplasmic fMet-tRNA formylated with Escherichia coli enzyme, and E. coli fMet-tRNA, do not hybridize with mitochondrial DNA. It is concluded that yeast mitochondrial tRNA(fMet) is a gene product of the mitochondrial genome.     

Sensitivity of Liver Mitochondrial Functions to Various Levels of Ethanol Intake in the Rat

Mitochondrial function appears to be an early target for ethanol toxicity, however it is not clear to what extent the effects of ethanol, which occur at levels of intake lower than those already reported in the literature, can induce an alteration of it. To produce different levels of ethanol intake, the spontaneous consumption of ethanol by genetically low (UChA) and genetically high (UChB) rats, as well as the forced intake obtained by offering 10% v/v ethanol solution as the only source of drinking fluid, were employed. The O2 uptake by liver mitochondria of rats submitted to these conditions in the presence of glutamate + malate, succinate or ascorbate + TMPD, was measured polarographically with a Clark electrode at 25 degrees C. Results indicate that alterations of the hepatic mitochondrial function can be detected at levels of ethanol intake much lower than those previously reported. Whereas, a level of a daily ethanol intake of 2-3 g/kg body weight in UChA rats under free choice was insufficient to produce detectable changes in the mitochondrial function, the latter was decreased in the high ethanol consumers (UChB), which drank 4-5 g/kg per day under free choice conditions, and in both strains forced to drink 10% ethanol as only source of fluid, which produced intakes of about 7 g/kg per day. Therefore, mitochondrial dysfunction may contribute to effects observed even at low levels of ethanol intake.     

Rho激酶抑制剂法舒地尔对急性缺血性卒中患者血清C-反应蛋白含量和转归的影响

目的:观察Rho激酶抑制剂法舒地尔对急性缺血性卒中患者血清C-反应蛋白(CRP)含量和转归的影响.方法:52例确诊急性缺血性卒中并在72 h内接受治疗的住院患者,根据入院时斯堪的纳维亚卒中量表(SSS)评分和一般情况进行配对,随机分入法舒地尔组和丁咯地尔组.法舒地尔组予盐酸法舒地尔60 mg,静脉滴注,2次/d(年龄＞70岁者30 mg,静脉滴注,3次/d);丁咯地尔组予盐酸丁咯地尔100 mg,静脉滴注,1次/d.两组疗程均为14 d.选择同期同龄健康体检人群26例作为对照组.所有患者于确诊次日清晨测定空腹血清CRP含量,并在治疗结束时复查SSS评分和血清CRP含量.CRP含量应用TurboxR特定蛋白分析系统(芬兰)以散射比浊法进行测定.结果:健康对照组血清CRP含量为(13.47±4.54)mg/L,略高于正常水平.丁咯地尔组和法舒地尔组治疗前CRP含量分别为(28.24±8.83)和(31.95±12.95)mg/L,显著高于对照组(P＜0.001).丁咯地尔组治疗后血清CRP含量为(24.10±10.07)mg/L,较治疗前有下降的趋势,但无显著差异;法舒地尔组治疗后为(15.10±3.92)mg/L,较治疗前显著降低(P＜0.001),与丁咯地尔组也有显著差异(P＜0.05).丁咯地尔组治疗后SSS评分为34.7±5.2,较治疗前(25.8±8.2)显著增高(P＜0.05).法舒地尔组治疗后SSS评分为47.6±6.1,较治疗前(26.3±7.2)显著增高(P＜0.001),与丁咯地尔组治疗后也有显著差异(P＜0.01).结论:Rho激酶抑制剂法舒地尔可显著改善急性缺血性卒中转归,可能与其降低血清CRP含量有关.     

Effect of Feldspar Substitution by Basalt on Pyroplastic Behaviour of Porcelain Tile Composition

This work aims to evaluate the effects of feldspar substitution by basalt on porcelain tile composition with respect to its porosity, flexural strength, and pyroplastic deformation. Three ceramic formulations with different amounts of feldspar substituted with basalt, 50% (C1), 75% (C2), and 100% (C3), were evaluated at three different temperatures, 1200, 1220, and 1240 °C. Specifically, the effect of replacing feldspar with basalt on the pyroplastic deformation of ceramic bodies was analysed using optical fleximetry. The porosity of C1 at 1200 °C was 19.3 ± 2.9%, while that of composition C3 was 22.2 ± 0.7% at 1240 °C. The flexural strength was strongly influenced by the temperature. For C1 at 1200 and 1240 °C, flexural strengths of 11.1 ± 0.6 and 22.2 ± 1.9 MPa, respectively, were obtained. Regarding fleximetry, thermal deformation decreased with an increase in the amount of feldspar substituted with basalt. It was observed that C2 and C3 deformed less at high temperatures than the other combinations of compositions and temperature, probably owing to the lower amount of residual glass phase present during cooling. Compositions with higher substitution amounts of basalt (i.e., C2 and C3) exhibited more stable thermal behaviour than C0.     

Maternally Inherited Diabetes Mellitus: the Role of Mitochondrial DNA Defects

Several studies have shown a consistent maternal effect in the transmission of Type 2 diabetes (NIDDM). The mitochondrial encephalomyopathies are a group of diseases characterized by maternal inheritance and a variety of mitochondrial DNA defects. Diabetes is a feature of some of these disorders and therefore the hypothesis arose that mitochondrial DNA mutations might play a role in patients with diabetes but no other features of neurological disease. Recent studies have confirmed that a specific point mutation in the gene encoding the mitochondrial tRNA for leucine segregates with diabetes and nerve deafness in families from the UK, Holland, France and Japan. Mitochondrial gene deletions have also been reported. Affected subjects present with progressive insulin deficiency and may fall into the broad classifications of either Type 1 (IDDM) or Type 2 diabetes (NIDDM). Future studies are aimed at searching for other mitochondrial gene defects in diabetes and attempting to explain the mechanism of hyperglycaemia by the development of phenotypic expression systems. Although an exciting development in the genetics of diabetes, currently described mitochondrial mutations do not fully explain the maternal effect in the transmission of Type 2 diabetes.