不同方法检测鼠疫动物脏器的研究

应用双重式聚合酶反应（Pla-F1-PCR)、常规细菌培养和反相血凝试验（RIHA），对9只实验感染鼠疫的动物脏器（豚鼠6份，小白鼠3份），在4℃条件下保存不同时间后进行同步检测。结果表明，保存90d和180d后，PCR与RIHA均为阳性，而细菌培养阳性率明显降低，PCR和RIHA法敏感性高于常规培养。提示对鼠疫或疑似鼠疫材料的检测除常规培养外应做PCR和RIHA，以防漏诊。     

电压门控钠通道亚单位在大鼠肠易激综合征模型中变化的研究

背景：电压门控钠通道（VGSC）在神经元动作电位的产生和传递中起着极为重要的作用。近年来它与内脏高敏感性的关系越来越受到重视。目的：探讨VGSC亚单位的变化与大鼠肠易激综合征（IBS）内脏高敏感性之间的关系。方法：以新生大鼠直肠内气囊扩张制作IBS的动物模型，在其成年后取L6-S2脊髓背根神经节，采用逆转录聚合酶链反应（RT-PCR）半定量法对背根神经节细胞表面VGSC Nav1．1、Nav1．6、Nav1．7、Nav1．8和Nav1．9五种α亚单位mRNA的含量进行检测．并以原位杂交的方法对Nav1．8的表达进一步加以确认；采用酶联免疫吸附试验（ELISA）法对大鼠肠道组织神经生长因子（NGF）的含量进行检测。结果：背根神经节细胞表面仅亚单位Nav1．8mRNA的表达增加，而Nav1．1、Nav1．6、Nav1．7和Nav1．9的表达没有改变，原位杂交定性分析也证实造模组Nav1．8含量增加；造模组肠道组织NGF的含量显著高于对照组。结论：新生大鼠直肠内气囊扩张使其脊髓背根神经节细胞Nay1．8mRNA的表达增加，而其他几种常见仅亚单位的含量均未发生改变。这种变化可能与肠道组织NGF表达的增加有关。     

Heterogeneity of the intrahepatic biliary epithelium

The objectives of this review are to outline the recent findings related to the morphological heterogeneity of the biliary epithelium and the heterogeneous pathophysiological responses of different sized bile ducts to liver gastrointestinal hormones and peptides and liver injury/toxins with changes in apoptotic, proliferative and secretory activities. The knowledge of biliary function is rapidly increasing because of the recognition that biliary epithelial cells (cholangiocytes) are the targets of human cholangiopathies, which are characterized by proliferation/damage of bile ducts within a small range of sizes. The unique anatomy, morphology, innervation and vascularization of the biliary epithelium are consistent with function of cholangiocytes within different regions of the biliary tree. The in vivo models [e.g., bile duct ligation (BDL), partial hepatectomy, feeding of bile acids, carbon tetrachloride (CCl4) orα-naphthylisothiocyanate (ANIT)] and the in vivo experimental tools [e.g., freshly isolated small and large cholangiocytes or intrahepatic bile duct units (IBDU) and primary cultures of small and large murine cholangiocytes] have allowed us to demonstrate the morphological and functional heterogeneity of the intrahepatic biliary epithelium. These models demonstrated the differential secretory activities and the heterogeneous apoptotic and proliferative responses of different sized ducts. Similar to animal models of cholangiocyte proliferation/injury restricted to specific sized ducts, in human liver diseases bile duct damage predominates specific sized bile ducts. Future studies related to the functional heterogeneity of the intrahepatic biliary epithelium may disclose new pathophysiological treatments for patients with cholangiopathies.     

Decreased protein levels of key insulin signalling molecules in adipose tissue from young men with a low birthweight – potential link to increased risk of diabetes?

Aims/hypothesis

Individuals with low birthweight are at increased risk of type 2 diabetes mellitus. However, the underlying molecular mechanisms are unknown. Previously we have shown that low birthweight is associated with changes in muscle insulin signalling proteins. Here we determined whether low birthweight is associated with changes in insulin signalling proteins in adipose tissue.

Methods

Men (age 23 years) with either a low (bottom 10th percentile) (n?=?17) or a normal (50th–90th percentile) (n?=?17) birthweight were recruited from the Danish Medical Birth Registry and subcutaneous adipose biopsies were taken.

Results

Between the two groups there was no difference in protein level of the insulin receptor, protein kinase C zeta, glycogen synthase kinase-3 (GSK3) alpha, GSK3 beta, protein kinase B alpha and beta, peroxisome proliferative activated receptor gamma coactivator 1 or Src-homology-2-containing protein. However, the levels of GLUT4 (also known as solute carrier family 2 [facilitated glucose transporter], member 4 [SLC2A4]) (52?±?10.9% reduction, p?p?p?=?0.06) and IRS1 (59?±?24% reduction, p?Conclusions/interpretation These findings show that low birthweight is associated with reduced levels of adipose insulin signalling proteins, thus providing a potential molecular framework to explain why people with low birthweight are at increased risk of developing type 2 diabetes. These differences precede the development of diabetes and thus may help predict disease risk.     

Intensive treatment of risk factors in patients with type-2 diabetes mellitus is associated with improvement of endothelial function coupled with a reduction in the levels of plasma asymmetric dimethylarginine and endogenous inhibitor of nitric oxide synthase.

AIMS: Vascular endothelium is a major organ involved in hyperglycaemia and is affected by plasma asymmetric dimethylarginine (ADMA). ADMA is an endogenous, competitive inhibitor of nitric oxide synthase and is induced by inflammatory cytokines of tumour necrosis factor (TNF)-alpha in vitro. We hypothesized that a tight glycaemic control may restore endothelial function in patients with type-2 diabetes mellitus (DM), in association with modulation of TNF-alpha and/or reduction of ADMA level. METHODS AND RESULTS: In 24 patients with type-2 DM, the flow-mediated, endothelium-dependent dilation (FMD: %) of brachial arteries during reactive hyperaemia was determined by a high-resolution ultrasound method. Blood samples for glucose, cholesterol, TNF-alpha, and ADMA analyses were also collected from these patients after fasting. No significant glycaemic or FMD changes were observed in 10 patients receiving the conventional therapy. In 14 patients who were hospitalized and intensively treated, there was a significant decrease in glucose level after the treatment [from 190+/-55 to 117+/-21 (mean+/-SD) mg/dL, P<0.01]. After the intensive control of glucose level, FMD increased significantly (from 2.5+/-0.9 to 7.2+/-3.0%), accompanied by a significant (P<0.01) decrease in TNF-alpha (from 29+/-16 to 11+/-9 pg/dL) and ADMA (from 4.8+/-1.5 to 3.5+/-1.1 microM/L) levels. The changes in FMD after treatment correlated inversely with those in TNF-alpha (R=-0.711, P<0.01) and ADMA (R=-0.717, P<0.01) levels. CONCLUSION: The intensive correction of hyperglycaemia is associated with the improvement of endothelial function, which is coupled with the decrease in the levels of reduction of plasma TNF-alpha and ADMA in patients with type-2 DM. A strict glycaemic control may exert anti-cytokine and anti-atherogenic effects and may therefore be pathophysiologically important.     

VEGF-expressing Bone Marrow Mesenchymal Stem Cells Transplantation Improved Heart Function of Myocardial Infarct Rabbits

Objectives To treat myocardial infarction with MSCs transplantation combined with VEGF gene therapy in rabbits and to study its mechanisms. Methods Forty-eight rabbits were randomly divided into MI group (n=12), MSCs group (n=12), VEGF group (n = 12), MSCs VEGF group (M V group, n = 12). Rabbit myocardial infarction models were founded by the ligation of left anterior descending artery. 107 MSCs were injected into the infarct-zone in four sites 2 weeks later in MSCs and M V group. phVEGF gene were injected in infarct-zone in VEGF group and MSCs transfected with phVEGF gene were injected in M V group. Heart function including LVEDP, LVSP, LVDP, -dp/dtmax dp/dtmax, were measured in vivo. The hearts were harvested at 4 weeks after transplantation and sectioned for HE stain, immunohistochemical stain of BrdU andⅧfactor antigen. Results The left ventricular hemodynamics parameters showed that heart function were improved more in M V group than MSCs group, MI group and VEGF group. The numbers of BrdU positive cells in M V group(61±8)were more than in MSCs group (44±8, P < 0.01). The numbers of vessels in infarcted zone were more in M V group (49±8) than in MSCs group (33±6, P < 0.01 ),VEGF group(30±8, P<0.01)and MI group (18±4, P<0.01). Conclusions VEGF- expressing MSCs transplantation could improve heart function after myocardial infarction, and they were more effective than sole MSCs transplantation. Keeping more MSCs survival and ameliorating the blood supply of infarct-zone might be involved in the mechanisms.     

Characterization of turkey and chicken ghrelin genes, and regulation of ghrelin and ghrelin receptor mRNA levels in broiler chickens

Ghrelin, a peptide hormone produced by the stomach in mammals, stimulates growth hormone release and food intake. Recently, ghrelin was identified and characterized in chicken proventriculus and shown to stimulate growth hormone release but inhibit feed intake. The purpose of this work was to identify and further characterize the ghrelin gene in chickens and in turkeys. Using molecular cloning techniques we have sequenced cDNAs corresponding to chicken (White Leghorn) and turkey ghrelin mRNAs. A total of 844 (chicken) or 869 (turkey) bases including the complete coding regions (CDS), and the 5'- and 3'-untranslated regions (UTRs) were determined. Nucleotide sequence (CDS) predicted a 116 amino acid precursor protein (preproghrelin) for both the chicken and the turkey that demonstrated complete conservation of an N-terminal 'active core' (GSSF) including a serine (position 3 of the mature hormone) known to be a modification (acylation) site important for ghrelin bioactivity. Additional nucleotide sequence was found in the 5'-UTRs of both Leghorn and turkey cDNAs that was not present in broilers or the red jungle fowl. The turkey ghrelin gene, sequenced from genomic DNA templates, contained five exons and four introns, a structure similar to mammalian and chicken ghrelin genes. Ghrelin was highly expressed in proventriculus with much lower levels of expression in other tissues such as pancreas, brain, and intestine. RT-PCR was used to quantify ghrelin mRNA levels relative to 18S rRNA in 3-week-old male broiler chickens. The level of ghrelin mRNA increased in proventriculus in response to fasting but did not decline with subsequent refeeding. Plasma ghrelin levels did not change significantly in response to fasting or refeeding and did not appear to reflect changes in proventriculus ghrelin mRNA levels. Ghrelin mRNA levels declined in broiler pancreas after a 48 h fast and increased upon refeeding. Expression of the gene encoding the receptor for ghrelin (growth hormone secretagogue receptor, GHS-R) and a variant form was detected in a variety of tissues collected from 3-week-old male broiler chickens possibly suggesting autocrine/paracrine effects. These results offer new information about the avian ghrelin and ghrelin receptor genes and the potential role that this system might play in regulating feed intake and energy balance in poultry.     

Genomic structure of the sea lamprey growth hormone-encoding gene

Growth hormone (GH) belongs to a family of pituitary hormones together with prolactin and somatolactin. In our previous study, GH and its cDNA were identified in the pituitary gland of the sea lamprey, Petromyzon marinus, an extant representative of the most ancient class of vertebrates, and isolated GH stimulated expression of insulin-like growth factor in the liver. The evidence suggests that GH is the ancestral hormone in the molecular evolution of the GH/PRL/SL family and that the endocrine mechanism for growth stimulation was established at an early stage in the evolution of vertebrates. To further understand the molecular evolution of the GH/PRL/SL gene family, we report the genomic structure of sea lamprey GH including its 5'-flanking region, being cloned by PCR using specific primers prepared from its cDNA. The sea lamprey GH gene consists of 13,604 bp, making it the largest of all the GH genes. The 5'-flanking region within 697 bp contains consensus sequences for a TATA box, two Pit-1/GHF-1, three TRE, and a CRE. The sea lamprey GH gene consists of five exons and four introns, the same as in mammals, birds, and teleosts such as cypriniforms and siluriforms with the exception of some teleosts such as salmoniforms, percififorms, and tetradontiforms, in which there is an additional intron in the 5th exon. The 5-exon-type gene organization might reflect the structure of the ancestral gene for the GH/PRL/SL gene family.     

BIG news in alcohol addiction: new findings on growth factor pathways BDNF, insulin, and GDNF

In recent years, it has become clear that growth factors are not only critical for the development of the central nervous system (CNS) but may also be important contributors to other neuronal functions in the adult brain. This symposium, presented at the 2005 RSA meeting, discussed evidence to support the hypothesis that alterations in growth factor pathways produce dramatic changes in the effects of alcohol on the CNS. The 4 speakers showed that the behavioral effects of alcohol in the adult are regulated by 3 growth factors, insulin, glial cell line-derived neurotrophic factor (GDNF), and brain-derived neurotrophic factor (BDNF). Dr. Wolf from the Heberlein laboratory presented findings obtained from genetic manipulations in Drosophila melanogaster, demonstrating that the insulin pathway controls sensitivity to the intoxicating effects of alcohol. Marian Logrip from the Ron and Janak laboratories presented evidence obtained in rodents that low concentrations of alcohol increase the expression of BDNF in the brain to regulate alcohol consumption. Dr. Pandey showed that amygdalar BDNF regulates alcohol's anxiolytic effects and preference. Finally, Dr. Janak presented evidence that increases in the expression of GDNF in the midbrain reduce alcohol self-administration in rats.     

Twin-block与MRC矫治生长高峰期伴口呼吸的骨性Ⅱ类疗效分析

目的:利用Twin-block与MRC对处于生长高峰期且伴口呼吸的骨性Ⅱ类进行治疗,分析对口呼吸的纠正效果和颌面部软硬组织的变化.方法:从2014～2019年采用Twin-block和MRC矫治且记录完整的错患者中,按纳入标准随机选择各20例.统计口呼吸被纠正的情况,测量分析治疗前后的头颅侧位片.结果:两组均表现为对...