Regulation of intercellular adhesion molecule-1 gene expression involves multiple mRNA stabilization mechanisms: effects of interferon- gamma and phorbol myristate acetate

Although the intercellular adhesion molecule-1 (ICAM-1) is constitutively expressed at a low level on a subpopulation of hematopoietic cells, on vascular endothelium, on fibroblasts, and on certain epithelial cells, it is dramatically increased at sites of inflammation. Interferon-gamma (IFN-gamma) and phorbol myristate acetate (PMA) are known to increase the expression of ICAM-1 on many cell types. Because both human and murine ICAM-1 mRNAs contain putative destabilizing AUUUA sequences in their 3' untranslated regions (UTRs), we examined the role of mRNA stability in the regulation of ICAM-1 gene expression. The treatment of the murine monocytic cell line P388D1, which constitutively expresses ICAM-1 mRNA at a low level, with IFN- gamma or PMA rapidly enhanced the level of ICAM-1 mRNA and dramatically prolonged its half-life. To determine whether the putative destabilizing sequences are responsible for this effect of IFN-gamma and PMA, fibroblast L cells were transfected with either the full- length ICAM-1 cDNA or a truncated form (ICAM-1 delta 3) lacking the putative destabilizing AUUUA sequences. Although ICAM-1 delta 3 mRNA was more stable than the full-length ICAM-1 mRNA, IFN-gamma treatment induced the accumulation of both mRNA species and prolongation of their half-lives. The transplantation of the ICAM-1 delta 3' UTR into a stable ICAM-2 mRNA rendered it unstable, and it was unresponsive to IFN- gamma. Therefore, the treatment with IFN-gamma stabilizes the otherwise labile ICAM-1 mRNA, but the IFN-gamma-responsive sequence may at least in part reside within the protein coding region. PMA also upregulated ICAM-1 gene expression by mRNA stabilization. However, unlike IFN- gamma, PMA treatment only increased the level of the full-length, but not of the truncated, ICAM-1 mRNA. This shows that the PMA-responsive element is located within the 3'UTR. Furthermore, the effect of PMA on ICAM-1 delta 3 mRNA was recovered by ligating multiple AUUUA sequences derived from a heterologous gene fragment. The stability of this chimeric mRNA and the full-length ICAM-1 mRNA was markedly increased by PMA treatment, indicating that the AUUUA multimers in the 3'UTR are important in the PMA-induced upregulation of ICAM-1 mRNA.     

Erythroid marrow function in anemic patients

Erythropoietic activity is known to be closely associated with marrow iron uptake. A modification of the standard measure of plasma iron turnover has been developed in which erythron transferrin uptake (ETU) rather than iron uptake has been calculated. The ETU has the advantage of providing a parameter of erythroid marrow activity independent of change produced by plasma iron and transferrin saturation. Measurements in 80 patients with anemia were compared to the normal value of 60 +/- 12 mumol/L whole blood/d. The mean ETU for ten patients with severe aplastic anemia and for six patients with pure red-cell aplasia were 12 +/- 8 and 12 +/- 11 mumol/L whole blood/d, respectively. In ten transfusion-dependent patients with renal failure under dialysis therapy, the mean value was 35 +/- 11, while ten other dialyzed patients who were transfusion independent had a mean ETU of 73 +/- 21 mumol/L whole blood/d. Sixteen patients with hemolytic anemia had an average ETU of 400 +/- 130, while 28 patients with ineffective erythropoiesis had a mean value of 474 +/- 147 mumol/L whole blood/d. While patients with hypoproliferative anemia showed no relation between the severity of anemia and ETU, those with hyperproliferative erythroid marrow showed increasing values as the anemia became more severe. Sequential measurements in patients with aplastic anemia under treatment and in thalassemic patients under transfusion therapy showed the value of this measurement in monitoring the effects of treatment on erythroid marrow activity. It is concluded that the measurement of ETU provides a more direct ferrokinetic evaluation of erythroid activity in anemic states.     

以公共卫生服务均等化为视角的血吸虫病防治工作

公共卫生服务均等化是指我国公民人人享有和获得基本公共卫生服务,其目标是保障城乡居民获得最基本、最有效的基本公共卫生服务。我国血吸虫病防治工作取得了显著的成就,为了进一步降低血吸虫病对人民群众的危害．满足其对血吸虫病防治服务的需求,建立长效的防治血吸虫病卫生服务机制．该文从公共卫生服务均等化视角,针对血吸虫病的防治工作进行探讨,以期加强基层血防工作,满足广大群众以健康为目标的防治血吸虫病卫生服务需求。达到均等化的目标。     

A variation in the ghrelin gene increases weight and decreases insulin secretion in tall,obese children

Ghrelin is a recently recognized gut-brain peptide originally derived from the gastric mucosa. It stimulates growth hormone release, increases appetite and facilitates fat storage, and may interact with glucose metabolism. We studied the ghrelin gene in a group of 70 tall and obese children (mean age 9.4 year, Z body mass index [BMI] and Z height >3 and/or BMI percentile >99%). We found 10 single nucleotide polymorphisms. One common polymorphism of the ghrelin gene, which corresponds to an amino acid change in the tail of the prepro-ghrelin molecule, was significantly associated with children with a higher BMI (P = 0.001), and with lower insulin secretion during the first part of an oral glucose tolerance test (P = 0.05) although no difference in glucose levels was noted. This might suggest increased insulin sensitivity, although this is not supported by the lack of difference in fasting and 2 hour insulin levels; alternatively, this may be indicative of impaired first phase insulin secretion. These data suggest that variations in the ghrelin gene contribute to obesity in children and may modulate glucose-induced insulin secretion.     

The major histocompatibility complex region marked by HSP70-1 and HSP70- 2 variants is associated with clozapine-induced agranulocytosis in two different ethnic groups

Genes of the major histocompatibility complex (MHC) have been associated with susceptibility to drug-induced adverse reactions. We previously found that clozapine-induced agranulocytosis (CA) is associated with the HLA-DRB1*0402, DRB4*0101, DQB1*0302, DQA1*0301 haplotype in Ashkenazi Jewish patients and with the HLA-DRB1*1601, DRB5*02, DQB1*0502, DQA1*0102 haplotype in non-Jewish patients. In the present study, we tested the hypothesis that the variants of the heat- shock protein 70 (HSP-70) encoded by the HSP-70 loci located within the MHC region and known to be involved in apoptosis and regulation of cell proliferation could play an important role in molecular mechanisms of CA. First, we analyzed HSP70-2 polymorphism in risk-associated haplotypes from HLA homozygous cells and normal individuals and confirmed that the HSP70-2 9-kb variant was associated invariably with DR4 (HLA-DRB1*0402, DQB1*0302) and DR2 (HLA-DRB1*01601, DQB1*0502, DQA1*0102 and HLA-DRB1*1501, DQB1*0602) haplotypes, which were the haplotypes found increased in Jewish and non-Jewish patients with CA, respectively. The 9.0-kb variant was also found to be associated with HLA-B44, DRB1*0401 and HLA-B44, DRB1*07 haplotypes. Second, in patients with CA (12 Ashkenazi Jewish and 20 non-Jewish patients), HSP70-1 A and HSP70-2 9.0-kb variants were associated with the MHC haplotypes found by us to be markers of susceptibility to CA. The clozapine-treated control group had an excess number of HSP70-1 C and HSP70-2 8.5-kb variants, consistent with genetic resistance to CA associated with those variants. This finding supports our hypothesis that a dominant gene within the MHC region (marked by HSP70-1 and HSP70-2), but not necessarily HLA, is associated with CA in two different ethnic groups.     

British HIV Association (BHIVA) national cohort outcomes audit of patients commencing antiretrovirals from naïve

Objectives

The aim of this work was to audit the extent to which routine HIV care in the UK conforms with British HIV Association (BHIVA) guidelines and specifically the proportion of patients starting highly active antiretroviral therapy (HAART) who achieve the outcome of virological suppression below 50 HIV‐1 RNA copies/mL within 6 months.

Methods

A prospective cohort review of adults with HIV infection who started antiretroviral therapy (ART) for the first time between April and September 2006 was carried out using structured questionnaire forms.

Results

A total of 1170 adults from 122 clinical sites participated in the review. Of these patients, 699 (59.7%) started ART at CD4 counts <200 cells/μL and 193 (16.5%) had not been tested for HIV drug resistance. Excluding patients with valid reasons for stopping short‐term ART, 795 (73.5%) of 1081 patients had an undetectable viral load (VL) at follow‐up. Detectable VL was strongly associated with pretreatment CD4 count below 50 cells/μL and pretreatment VL above 100 000 copies/mL, and was not associated with clinic location or case load. About a quarter of patients did not have a VL measurement during the first 6 weeks after starting ART.

Conclusions

The majority of patients who initiated ART at sites participating in this UK national audit were managed within the BHIVA guidelines and achieved virological suppression below 50 copies/mL around 6 months after commencing treatment. Poor VL outcomes were associated with very low CD4 cell count and/or high VL at baseline but not with clinic case load or location. There is an urgent need to diagnose patients at an earlier stage of their HIV disease.     

日本血吸虫SjCa8基因的原核表达及其免疫学特征分析

目的表达和纯化日本血吸虫钙结合蛋白(SjCa8),研究其免疫学特征。方法重组质粒pET32a ( )-SjCa8经诱导表达后,获取纯化蛋白SjCa8,利用ELISA、Western-blot和动物保护性实验检测SjCa8的免疫学特征。结果成功获取了纯化蛋白SjCa8,该蛋白能免疫识别血吸虫感染小鼠血清和血吸虫病患者血清。SjCa8免疫Balb/c小鼠可获得较高滴度的特异性抗体,诱导宿主产生35．31%的减虫率和35．68%的减卵率。结论纯化蛋白SjCa8具有良好的免疫原性和免疫反应性,具有作为血吸虫病免疫诊断和疫苗候选分子的研究价值。     

八项肝纤维化血清标志物比较研究

目的比较血清血小板衍生生长因子-BB(PDGF-BB)、转化生长因子-β1(TGF-B1)、基质金属蛋白酶抑制剂-1(TIMP-1)、基质金属蛋白酶-1(MMP-1)、透明质酸(HA)、Ⅲ型前胶原(PC Ⅲ)、Ⅳ型胶原(C Ⅳ)和层黏连蛋白(LN)及外周血单个核细胞(PBMC)内TIMP-1 mRNA、MMP-1 mRNA在肝纤维化中的诊断价值。方法常规肝穿活检、组织病理学诊断；RT-PCR检测PBMCs中MMP-1 mRNA、TIMP-1 mRNA水平；酶标法检测血清PDGF-BB、TGF-β1、TIMP-1和MMP-1含量；放射免疫法检测血清HA、PC Ⅲ、C-Ⅳ和LN含量。结果经ROC曲线分析，血清PDGF-BB、TIMP-1、HA、PC Ⅲ、C-Ⅳ、LN和TIMP-1 mRNA的AUC分别为0．985、0．726、0．318、0．728、0．727、0．583、0．463、0．876；血清PDGF-BB和PBMCs中TIMP-1 mRNA的灵敏度和特异度分别为90％、95％，73．7％、100％；两者联合检测的灵敏度为97．4％，特异度为95．0％。结论八项指标中，血清PDGF-BB的诊断价值最大。在筛选肝纤维化患者时，以血清PDGF-BB、PBMC中TIMP-1 mRNA联合检测最佳。