α-葡萄糖苷酶抑制剂治疗2型糖尿病的系统评价

目的评价α-葡萄糖苷酶抑制剂治疗2型糖尿病患者的效果。方法检索Cochrane图书馆、MEDLINE、EMBASE、CurrentContents、LILACS在研试验数据库,主题为α-葡萄糖苷酶抑制剂的综述的参考文献,并联系纳入试验的专家与实施者。最近检索日期为2003年月12月(CurrentContents)和2003年4月(其他数据库)。纳入α-葡萄糖苷酶抑制剂单一疗法与其它干预比较,治疗2型糖尿病疗程至少12周的随机对照试验,并且试验至少包括以下结局之一:病死率、患病率、生活质量、血糖控制、血脂、胰岛素水平、体重、不良事件。两名评价者独立阅读所有摘要,评价质量并提取数据,分歧通过协商解决或由第三位评价者裁决。由一位统计学家在对提取数据输入数据库时进行检查。我们尽量联系所有作者以核实数据。结果共纳入41个试验、8130例受试者,其中30个针对阿卡波糖,7个针对米格列醇,1个针对优格列波糖,还有3个为不同α-葡萄糖苷酶抑制剂间的比较。绝大多数研究疗程为24周,仅有2个研究超过1年。与安慰剂相比,阿卡波糖血糖控制效果更好:糖化血红蛋白–0.8%[95%CI(–0.9,–0.7)],空腹血糖–1.1mmol/L[95%CI(–1.4,–0.9)],负荷血糖–2.3mmol/L[95%CI(–2.7,–1.9)],阿卡波糖对糖化血红蛋白的作用呈非剂量依赖。我们发现其可降低负荷胰岛素,但对血脂和体重未见临床相关的作用。不良反应主要来自胃肠道且与剂量相关。相对于磺脲,阿卡波糖将空腹和负荷胰岛素水平分别降低至–24.8pmol/L[95%CI(–43.3,–6.3)]和–133.2pmol/L[95%CI(–184.5,–81.8)],但阿卡波糖引起的不良反应更多。结论关于α-葡萄糖苷酶抑制剂是否影响2型糖尿病患者的病死率和患病率仍不清楚。相反,其对血糖控制或胰岛素水平作用明显,对血脂和体重的作用差异无统计学意义。α-葡萄糖苷酶抑制剂更长疗程的效果仍不确定。阿卡波糖剂量超过50mg(TID)时不能进一步影响糖化血红蛋白水平,不良反应反而更多,与磺脲相比,α-葡萄糖苷酶抑制剂降低了空腹和负荷胰岛素水平,但在血糖控制和不良反应方面存在不利影响。     

The relationship between hypertension and anxiety or depression in Hong Kong Chinese

BACKGROUND:

Psychosocial stress can be the cause or the consequence of hypertension.

OBJECTIVE:

To study the association between hypertension and anxiety or depression in adults from Hong Kong, China.

SUBJECTS AND METHODS:

Patients with diagnosed hypertension (n=197) were recruited to complete the Hospital Anxiety and Depression Scale (HADS) questionnaire. The control group comprised 182 normotensive subjects recruited using random telephone numbers.

RESULTS:

The score in the anxiety subscale (HADS-A) of the HADS correlated with age (r= −0.23, P<0.001) and sex (r=0.11, P=0.042), and was found to be higher in women. The score in the depression subscale (HADS-D) correlated with age (r=0.17, P=0.003) and hypertension (r=0.12, P=0.039), but not with sex (r=0.02, P=0.68). When the control subjects were matched for sex and age with the subjects with hypertension, the mean HADS-A score was 5.51±0.41 in 113 hypertensive subjects and 4.38±0.39 in 113 normotensive subjects (P=0.047). The mean HADS-D score was 5.56±0.39 in the hypertensive and 4.76±0.32 in the normotensive subjects (P=0.11). Multiple regression analysis using data from both groups indicated that the HADS-A score was related to the HADS-D score (β=0.49, P<0.001), age (β= −0.25, P<0.001) and sex (β=0.12, P=0.01) (R²=0.28), whereas the HADS-D score was related to the HADS-A score (β=0.48, P<0.001), age (β=0.30, P<0.001), positive smoking status (β=0.13, P=0.004) and lack of exercise habit (β=0.12, P=0.008) (R²=0.31). Hypertension was related to waist circumference, history of parental hypertension and age (R²=0.38, P<0.001). Anxiety and depression scores were rejected as independent variables.

CONCLUSIONS:

Hypertension was associated with anxiety but not depression; however, age, history of parental hypertension and central obesity appeared to have a stronger association with hypertension in adults from Hong Kong.     

Identification of a new Leu354Pro mutation responsible for factor XIII deficiency

We report a new homozygous CTG-->CCG (Leu-->Pro) mutation at codon 354 in the factor XIIIA gene of a patient suffering from FXIII deficiency. Leu354 lies in a pocket within the core domain of the FXIIIA molecule, with its side chain pointing into the structure of the barrel 1 domain. Replacement of leucine with a proline residue gives rise to steric hindrance between the proline ring and the surrounding residues, and rearrangement of these residues would be necessary for proline to be accommodated at this position. Using PCR-RFLP, we have demonstrated the absence of this mutation from 220 normal alleles. Together, these data suggest that Leu354Pro is likely to be the disease-causing mutation in this factor XIII deficient family.     

肝纤维化的发生机制与治疗进展

肝纤维化是各种致病原因引起细胞外基质(ECM)在肝内过多沉积的病理过程．在细胞和分子发病机制方面的研究显示,细胞因子作用于窦周间隙静止的肝星状细胞(HSC)使其转变为激活状态,继而增殖,合成ECM．因此认为激活的HSC是产生ECM的主要细胞,其他如肝静脉区成纤维细胞和骨髓源性肌成纤维细胞也是某些肝纤维化初期的主要纤维原性细胞．目前认为,进展性肝纤维化具有可逆性．药物旨在通过抑制HSC的激活、诱导其凋亡和防止ECM沉积的干预性治疗在实验性肝纤维化已取得疗效,但人类抗肝纤维化的有效性和安全性有待于进一步研究和论证．     

The cytoplasmic domain of P-selectin is phosphorylated on serine and threonine residues

P-selectin is an adhesion receptor for leukocytes that is redistributed from secretory granule membranes to the surfaces of activated platelets and endothelial cells. The cytoplasmic domain of P-selectin contains two serines, two threonines, and one tyrosine that could potentially be phosphorylated. We found that P-selectin was phosphorylated in both platelets and endothelial cells and that phosphorylation rapidly increased after cell activation. Approximately 0.02, 0.05, and 0.08 mol of phosphate/mol of P-selectin were incorporated, respectively, into resting, thrombin-activated, and phorbol ester-activated platelets. Phosphorylation was completely inhibited by the protein kinase C inhibitors, staurosporine, H-7, and chelerythrine, and was enhanced by the phosphatase inhibitors, okadaic acid and calyculin-A. Phosphoamino acid analysis of 32P-labeled P-selectin showed that phosphorylation occurred predominantly on serine with lesser amounts on threonine. When expressed in transfected Chinese hamster ovary cells, P-selectin was also phosphorylated. Mutagenesis studies showed that Ser788 was the principal site of phosphorylation, with minor sites on the other serine and threonine residues of the cytoplasmic domain. Phosphorylation may regulate membrane trafficking or other functions of P-selectin.     

Compound heterozygosity for Hb S [β6(A3)Glu→Val] and Hb Kenya (Aγ81Leu-β86Ala) in a Ugandan woman

Hb Kenya is a hemoglobin (Hb) tetramer composed of two normal α- and two non α-globin chains. The latter are the product of a fusion gene in which the 5' end is (A)γ and the 3' end is β. The crossover point is between codon 81 of the (A)γ gene and codon 86 of the β gene. Like the other non α genes, the hybrid protein product ((A)γ81Leu-β86Ala) has 146 amino acids. The purpose of this report is to highlight the laboratory findings of Hb Kenya and to emphasize the pitfalls in misdiagnosis, particularly when associated with another variant such as Hb S [β6(A3)Glu→Val].     

Effectiveness of methyl-GAG (methylglyoxal-bis[guanylhydrazone]) in patients with advanced malignant lymphoma

We treated 51 patients with advanced malignant lymphoma refractory to conventional therapy with methyl-glyoxal-bis(guanylhydrazone) (methyl- GAG) at doses ranging from 400 to 800 mg/sq m. Therapy was started on a weekly schedule and was switched to every other week in responding patients at the onset of toxicity. Partial responses were observed in 6 of 13 evaluable patients with Hodgkin's disease (46%), 5 of 10 patients with diffuse poorly differentiated lymphocytic lymphoma (50%), 2 of 4 patients with nodular poorly differentiated lymphocytic lymphoma (50%), and 3 of 13 patients with diffuse histiocytic lymphoma (23%). Two of six patients with mycosis fungoides showed objective improvement in cutaneous disease. Toxicity was generally mild and included muscular weakness, myalgia, mucositis, and diarrhea; two patients developed bronchospasm following drug infusions. We conclude that methyl-GAG has major antitumor activity when administered on this schedule to patients with advanced malignant lymphoma. The low degree of toxicity, unique mechanism of action, and minimal myelosuppressive effects suggest that methyl-GAG will prove useful in future trials of combination chemotherapy regimens for the treatment of lymphoma.     

Induction of apoptosis in human eosinophils by anti-Fas antibody treatment in vitro

Fas antigen (CD95) can induce apoptosis of cells such as lymphocytes and neutrophils. To determine whether Fas antigen is involved in eosinophil apoptosis, we examined its expression and function on eosinophils in vitro. Purified human eosinophils expressed low but consistently detectable levels of Fas antigen. Culture of eosinophils in up to 10 ng/mL interleukin-5 (IL-5) prolonged eosinophil survival; incorporation of 1 to 1,000 ng/mL Fas antibody led to significant reductions in IL-5-induced eosinophil viability after 48 to 72 hours of culture. Reductions in survival could not be overcome by IL-5 and also occurred in the absence of exogenous IL-5. Preactivation of eosinophils with platelet-activating factor (PAF) significantly reduced eosinophil viability without altering the survival-reducing effects of Fas antibody treatment. In contrast, RANTES did not affect eosinophil viability or Fas antibody-induced reductions in eosinophil survival. After treatment with Fas antibody, electron microscopy of eosinophils and gel electrophoresis of DNA extracted from eosinophils demonstrated changes consistent with apoptosis. These data demonstrate that Fas antigen can modify eosinophil survival by inducing apoptosis through a pathway that is, at least in part, independent of the survival- promoting effects of IL-5.