Rectal wall contractility in healthy subjects and in patients with chronic severe constipation.

OBJECTIVE: The aim of this study was to identify differences in rectal wall contractility between healthy volunteers and patients with chronic severe constipation. SUMMARY BACKGROUND DATA: Whether motor function of the rectum contributes to slow-transit constipation is unknown. Measurements of rectal contractility have been performed traditionally with perfused catheters or microtransducers. The rectal barostat is a new technique that quantifies the volume of air within an infinitely compliant intrarectal bag maintained at constant pressure; decreases in bag volume therefore reflect increases in rectal muscular contractility (tone). Increases in volume reflect decreased contractility. METHODS: Fifteen healthy volunteers (ten women and five men; mean age, 36 years) and eight patients (seven women and one man; mean age, 44 years) were studied. Barostat recordings were made for 1 hour before and after a meal. Randomly, neostigmine (0.5 mg) or glucagon (1 unit) was then given intravenously. After 1 hour, the other medication was given. RESULTS: The fasting rectal volume was similar in the patient and control groups (113 +/- 7 mL vs. 103 +/- 4 mL, respectively; p > 0.05). Compared with controls, constipated patients had a significantly lower reduction in rectal volume after a meal (constipated, 35 +/- 8% vs. controls, 65 +/- 7%; p < 0.05) and after neostigmine administration (constipated, 39 +/- 6% vs. controls, 58 +/- 6%; p < 0.05). Moreover, constipated patients had a smaller increase in rectal volume after glucagon administration than did controls (28 +/- 6% vs. 64 +/- 18%, respectively; p < 0.05. CONCLUSIONS: Changes in rectal wall contractility in response to feeding, a cholinergic agonist, and a smooth muscle relaxant were decreased in constipated patients. These findings suggest that an abnormality of rectal muscular wall contractility is present in constipated patients.     

参三七皂甙Rg1对实验性血栓形成的影响及其机制探讨

用大鼠动静脉血栓形成模型,研究参三七皂甙Rg₁抗血栓作用。结果表明,参三七皂甙Rg₁可明显降低实验性血栓形成,对大鼠血浆纤溶系统亦有明显作用,可升高血浆中组织纤溶酶原激活物(t-PA)活性和活性型t-PA百分比,降低组织纤溶酶原激活物抑制剂(PAI)活性。同时利用培养大鼠血管内皮细胞实验,发现Rg₁可以剂量依赖性提高血管内皮细胞一氧化氮(NO)释放。提示Rg₁抗血栓作用与增强纤溶系统活性,促进血管内皮NO释放有关。     

Trabecular bone architecture in female renal allograft recipients-- assessed by computed tomography

BACKGROUND: Osteopenia with decreased bone mineral density (BMD) is a frequent finding in renal allograft recipients. Data concerning the bone architecture in these patients do not exist, however. METHODS: We compared the bone architecture of 33 randomly assigned women (age 49 +/- 12 years), who had received renal allografts 5.6 +/- 5.3 years before the investigation, with 74 women (age 50 +/- 14 years) who were admitted for osteodensitometry. All patients underwent single-energy computed tomography (SEQCT) and a midvertebral high-resolution tomography with computer-assisted analysis of the trabecular vertebral body architecture. RESULTS: Progressive alteration of bone architecture was associated with increasing vertebral height loss of the vertebral body. Height reduction of a vertebral body of more than 15% was associated with a significantly lower BMD (-2.3 +/- 0.8 versus -1.1 +/- 1.1 standard deviations below normal BMD), a lower trabecular bone area (13 +/- 8% versus 42 +/- 22%) and a lower trabecular diameter (1.4 +/- 0.5 mm versus 2.2 +/- 0.8 mm) compared to recipients without height reduction. In comparison to a matched group of patients with similarly reduced BMD (1.1 +/- 1.2 versus 1.2 +/- 1.1 SD below normal BMD), renal allograft recipients showed a lower number of trabecular plates (5.6 +/- 3.1 versus 7.0 +/- 3.7) and a smaller intertrabecular surface (54 +/- 116 mm versus 75 +/- 138 mm). CONCLUSIONS: Alterations of bone architecture in renal allograft recipients were associated with progressive vertebral height loss. Despite similar bone mineral density, differences of bone architecture could be observed between renal allograft recipients and patients with osteoporosis.      

间硝地平对左室肥厚大鼠左室舒张功能及心脑线粒体和血管组织钙含量的影响

用肾性高血压左室肥厚(LVH)大鼠模型,观察了间硝地平(m-Nif)和硝苯地平(Nif)长期给药(ig20mg·kg^-1·d^-1持续9周)对左室舒张功能、左心室肌和大脑线粒体及血管钙含量的影响。与假手术组相比,LVH组左室顺应性明显下降,僵硬度增高,左心室肌和大脑线粒体及尾动脉和主动脉钙含量增加。与LVH组相比,m-Nif和Nif各组左室顺应性改善,僵硬度降低(P<0.01),左心室肌线粒体及尾动脉和主动脉钙含量较LVH组显著降低(P<0.01)。两药在作用强度上无显著差异。     

Innovation in clinical method: diabetes care and negotiating skills

The development of a method to facilitate clinical negotiationwith diabetic patients is described. The principles of the methodincorporate patient centredness, an assessment of readinessto change and some elements of motivational interviewing. Asimple low cost technology is part of the innovative method.Details of the method and its application are published beforethe results of a randomized controlled trial to ensure thatthe techniques are in the public domain before the outcome ofthe trial is known.     

Leucocytoclastic vasculitis associated with hepatitis C virus antibodies

The actiopathogenesis of leucocytoclastic vasculitis is still unknown, but recently hepatitis C virus (HCV) has been suggested as trigger of autoimmunity. We report a case of a 26-yr-old patient with purpura due to leucocytoclastic vasculitis associated with hepatitis C virus infection. Laboratory findings showed AST, ALT, gamma GT within normal limits, positive antibodies to HCV (IIF and Riba II) and polymerase chain reaction for HCV RNA. Anti-nuclear antibodies, IgG and IgM anti- cardiolipin antibodies, anti-platelet antibodies and anti-neutrophil cytoplasmic antibodies with perinuclear pattern were also present. A skin biopsy specimen of a purpuric lesion showed leucocytoclastic vasculitis with small vessel thrombosis and perivascular deposition of IgM and fibrinogen on immunofluorescence study. This case shows a role of HCV in leucocytoclastic vasculitis; it is possible that this HCV can induce autoimmunity independently of cryoglobulins and liver involvement.      

Central thrombi in pulmonary arterial hypertension detected by MR imaging

Differentiation of thrombi from slow flow in the pulmonary arteries, sometimes observed in the presence of pulmonary arterial hypertension, can be equivocal. Magnetic resonance (MR) imaging was performed in a patient with chronic pulmonary thromboembolism and pulmonary arterial hypertension using an electrocardiographically gated technique that allowed visualization of the pulmonary arteries at the end of diastole and multiple times during systole. These images were compared with those of a patient with primary pulmonary hypertension and those of healthy subjects. Thrombi were discrete structures, seen throughout the cardiac cycle on both the first and second spin-echo images, and decreased in signal intensity on the second image. Slow flow increased in signal intensity and changed in structure during the cardiac cycle and was seen best on the second image. MR may play an important role in excluding large central thrombi as the cause of pulmonary arterial hypertension. It is a noninvasive method for defining pulmonary arterial wall thickness and for direct visualization of chronic pulmonary thrombus.