门诊与住院患者口服抗凝剂治疗的安全性指征

1 引言 英国血液标准化委员会于1998年公布了第三版口服抗凝剂治疗指南,并于2006年修订.这些指南在安全性指征方面值得称道,但对开始口服抗凝剂治疗患者和已持续进行口服抗凝剂治疗的患者来说,安全性指征和危险性是相互伴随的.并非所有的安全性指征都要被医务工作者所采纳,而是为他们提供一种选择,可根据具体情况和需求选择最有用的指标.为了医疗服务的健康发展,这些安全性指征可以用来设立各种标准和规范,并进行相应的监督和审计.     

Mutations and impaired function of LKB1 in familial and non-familial Peutz-Jeghers syndrome and a sporadic testicular cancer

Germline mutations in LKB1 have been reported to underlie familial Peutz-Jeghers syndrome (PJS) with intestinal hamartomatous polyps and an elevated risk of various neoplasms. To investigate the prevalence of LKB1 germline mutations in PJS more generally, we studied samples from 33 unrelated PJS patients including eight non-familial sporadic patients, 20 familial patients and five patients with unknown family history. Nineteen germline mutations were identified, 12 (60%) in familial and four (50%) in sporadic cases. LKB1 mutations were not detected in 14 (42%) patients, indicating that the existence of additional minor PJS loci cannot be excluded. LKB1 is predicted to encode a serine/threonine kinase. To demonstrate the putative Lkb1 kinase function and to study the consequences of LKB1 mutations in PJS and sporadic tumors, we have analyzed the kinase activity of wild-type and mutant Lkb1 proteins. Interestingly, while most of the small deletions or missense mutations resulted in loss-of-function alleles, one missense mutation (G163D) previously identified in a sporadic testicular tumor demonstrated severely impaired but detectable kinase activity.      

Follistatin is a candidate endogenous negative regulator of activin A in experimental allergic asthma

BACKGROUND: Activin A is a member of the transforming growth factor-beta superfamily which is directly implicated in airway structural change and inflammation in asthma. In vitro, the biological effects of activin A are neutralized by the soluble binding protein follistatin. OBJECTIVE: To determine the potential of endogenous follistatin to suppress activin A in vivo by analysing their relative tissue and kinetic compartmentalization during the effector phase of subchronic Th2-driven mucosal inflammation in a murine model of allergic asthma. METHODS: Eosinophilic mucosal inflammation was elicited by triggering Th2 recall responses by antigen challenge in ovalbumin-sensitized BALB/c mice. The kinetics and distribution of activin A and follistatin protein were assessed in lung tissue and bronchoalveolar lavage fluid and measured in relation to airway eosinophilia, goblet cell metaplasia and Th2 cytokine production in mediastinal lymph nodes. RESULTS: Follistatin was released concurrently with activin A suggesting it acts as an endogenous regulator: peak BAL concentrations coincided with maximal airway eosinophilia, and frequency of IL-4, IL-5 and IL-13 producing cells in mediastinal lymph nodes but induction lagged behind the onset of inflammation. Follistatin and activin A immunoreactivity were lost in airway epithelial cells in parallel with goblet cell metaplasia. Exogenous follistatin inhibited the allergen-specific Th2 immune response in mediastinal lymph nodes and mucus production in the lung. CONCLUSION: Follistatin is preformed in the normal lung and released in concert with activin A suggesting it serves as an endogenous regulator. Disturbance of the fine balance between activin A and its endogenous inhibitor follistatin may be a determinant of the severity of allergic inflammation or tissue phenotypic shift in asthma.     

Preoperative weight loss is not a predictor of postoperative weight loss after laparoscopic Roux-en-Y gastric bypass

BACKGROUND: Identification of preoperative predictors of weight loss after laparoscopic Roux-en-Y gastric bypass (LRYGB) can lead to improved clinical outcomes. The purpose of this study was to determine whether preoperative weight loss was associated with improved percentage of excess weight loss (%EWL) 1 year after LRYGB. METHODS: A retrospective analysis was performed on the data from 295 patients who had undergone LRYGB at our institution from July 2004 to November 2005. Routine preoperative weight loss goals were implemented to facilitate the laparoscopic approach and ensure compliance with an appropriate nutritional and exercise program. Patients with an initial consultation BMI of <50, 50-59, and > or =60 kg/m(2) were given weight loss goals of 5 lb and 5% and 10% of body weight, respectively. RESULTS: The mean age was 45 +/- 10 years, and 89% were women and 70% were white. The mean BMI at the initial consultation was 51 +/- 7 kg/m(2). A significant inverse correlation was found between the preoperative BMI and %EWL at 1 year postoperative (P <.001). When controlling for BMI, no correlation was found between the %EWL and percentage of preoperative weight loss or attainment of the weight loss goals. The weight loss goals were met or surpassed by 79% of patients, and the mean %EWL at 1 year was 66%. Whites had greater %EWL at 1 year postoperatively compared with African Americans (67% versus 61%; P = .002). When controlling for age, gender, race, and consultation BMI, the preoperative weight loss did not predict for the %EWL at 1 year. CONCLUSION: The results of this study have shown that preoperative weight loss does not predict postoperative weight loss 1 year after LRYGB. A lower BMI, younger age, and white race predicted better %EWL.     

Acute transformation of essential thrombocythaemia: report of two cases.

Two cases of leukaemic transformation are reported, one to acute lymphoblastic leukaemia associated with a 14q+ marker chromosome and the other to acute monocytic leukaemia, occurring 20 and 30 years, respectively, after the original diagnosis was made.     

Comparison of the haemodynamic effects of bucindolol, propranolol and pindolol in healthy volunteers.

The effects of single oral doses of bucindolol (50, 100, 200 and 400 mg), pindolol (10 mg), propranolol (160 mg) and placebo on arterial pressure and heart rate in the supine and standing positions and exercise heart rate were compared in 12 healthy male volunteers. Supine heart rate was significantly greater after all four doses of bucindolol and pindolol in comparison to propranolol. Bucindolol had no significant effect on standing heart rate which was significantly reduced by pindolol and propranolol. Bucindolol, pindolol and propranolol significantly reduced an exercise tachycardia for at least 24 h after drug administration. Supine systolic pressure was not affected by any treatment but supine diastolic pressure was significantly reduced by bucindolol (200 and 400 mg) and by pindolol. All doses of bucindolol, propranolol and pindolol significantly reduced standing systolic blood pressure. There was a significant linear trend for reductions in standing systolic blood pressure and increasing doses of bucindolol. Standing diastolic blood pressure was significantly reduced by bucindolol 200 and 400 mg. Faintness and light headedness occurred in 6 of 12 subjects after 200 mg bucindolol and in 8 of 10 subjects after 400 bucindolol. After bucindolol, analysis of plasma samples demonstrated the presence of bucindolol, 5-hydroxy and 6-hydroxy bucindolol and indolyl-t-butylamine. These observations indicate that in man, bucindolol is a beta-adrenoceptor blocking drug with hypotensive activity and probably partial agonist activity. It is unlikely that the hypotensive effects result from blockade of beta-adrenoceptors or from the drug's partial agonist activity.     

Lesions of the optic radiations mimicking lateral geniculate nucleus visual field defects.

Three patients were found to have visual field defects which involved homonymous horizontal sectors of the visual fields, thus mimicking field defects associated with lesions of the lateral geniculate nucleus. Computed tomography provided anatomical evidence that the responsible lesion involved the optic radiations rather than the lateral geniculate nucleus.     

Supratentorial ependymoma: CT appearance

The computed tomographic appearances of 22 biopsy-proved supratentorial ependymomas were analyzed. Supratentorial ependymomas were usually intraparenchymal, larger than 4 cm, and cystic. Contrast enhancement was moderate to intense, with homogeneous or ring-enhancement patterns commonly seen. Intratumoral calcification was present in one-third of the cases, while hydrocephalus and peritumoral edema were seen in 50%. Intratumoral hemorrhage was not a characteristic of the lesion. In contrast to cellular ependymomas, malignant ependymomas and ependymoblastomas demonstrate higher attenuation prior to administration of contrast material, more intense enhancement, lower frequency of calcification within the tumor, and less distinct margination.