Pathogenesis of diabetic retinopathy and the renin-angiotensin system.

Despite the beneficial effects of good glycaemic control, loss of vision because of diabetic retinopathy (DR) still occurs. Recent studies have suggested that hypertension is a risk factor for the development and progression of DR and that blood pressure reduction can delay the progression of retinopathy. The renin-angiotensin system is activated by chronic hyperglycaemia, and the vitreous fluid level of angiotensin II (AII) is elevated in patients with proliferative diabetic retinopathy and diabetic macular oedema. AII increases vascular permeability and promotes neovascularization. It has been suggested that an autocrine-paracrine relationship may exist between AII and vascular endothelial growth factor in the ocular tissues. Accordingly, angiotensin-converting enzyme inhibitors or AII Type 1 (AT1) receptor blockers may be useful therapeutic agents for preventing the progression of DR.     

Thrombophilic risk factors and unusual clinical features in three Italian CADASIL patients

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a genetically transmitted cerebrovascular disease. Typically, the first clinical manifestation is migraine and the full clinical spectrum of the disease with recurrent strokes of the subcortical type, cognitive, and mood disorders is seen during the fourth and fifth decades of life. Vascular risk factors are usually absent in CADASIL patients and the diagnosis of the disease is particularly suspected in young adults with cerebrovascular events of unknown cause, diffuse leukoencephalopathy on computed tomography or magnetic resonance imaging, and a history of cerebrovascular diseases or dementia in many family members. We describe three Italian CADASIL patients who presented to medical attention for cerebrovascular events occurred after the age of 55 and had, in addition to hypertension and hyperlipidemia, thrombophilic risk factors such as hyperhomocysteinemia, elevated levels of lipoprotein(a), and antiphospholipid antibodies. Symptoms possibly related to cortical involvement, such as dysphasia and visual field deficits, were reported by two of these patients. We conclude that a diagnosis of CADASIL should not be disregarded in patients with vascular risk factors and presenting with symptoms not immediately referable to subcortical damage at ages more advanced than commonly reported.     

视盘血管袢的临床特征

目的：了解视盘血管袢的临床特征。方法：回顾分析我院自开展荧光素眼底血管造影以来的诊断为视盘血管袢的14例(16眼)临床资料。结果：视盘血管袢62．5％的分布于视盘上方；动脉袢10眼，静脉袢6眼；合并玻璃体积血8眼；视力在0．5以下者占78．5％。结论：视盘血管袢动脉居多，多于视盘上方，影响视力的主要原因为合并症。     

内皮细胞生长因子诱导大鼠血管内皮细胞增殖过程中FKBP12的表达

目的探讨内皮细胞生长因子(Endothelial cell growth factor，ECGF)诱导的血管内皮细胞(Vascular endothelial cell，VEC)增殖过程中FK506结合蛋白12(FK506 binding protein 12，FKBP12)表达的变化，为VEC的鉴定提供新的方法。方法培养大鼠VEC并传代。倒置显微镜下观察其在ECGF作用下的增殖情况，检测Ⅷ因子相关抗原、FKBP12和不同时期FKBP12 mRNA水平的表达。结果VEC表达FKBP12；VEC传代后第4天FKBP12 mRNA表达水平达到最高，6—8d下降。结论FKBP12既可作为VEC的标志物，又可反映VEC的增殖情况。     

多普勒超声心动图测量肺血管阻力

目的:探讨多普勒超声心动图无创测量肺血管阻力(PVR)的方法。方法:采用多普勒超声技术检测22例正常儿童(对照组)和50例经右心导管检查的先心病患儿(病例组)的三尖瓣最大反流速度(TRV)、右室流出道血流速度时间积分(VTIRVOT)、肺动脉瓣最大反流速度(PIV)、肺动脉血流速度时间积分(VTIPA),计算TRV/VTIRVOT值、TRV/VTIPA值及PIV/VTIPA值,比较两组的差异,并将病例组TRV/VTIRVOT值、TRV/VTIPA值及PIV/VTIPA值与导管所测的PVR进行相关与回归分析。结果:对照组与病例组的TRV/VTIRVOT、PIV/VTIPA及TRV/VTIPA值差异有显著性意义(P<0.05),且病例组的PIV/VTIPA值和TRV/VTIPA值与心导管所测PVR值间呈高度正相关(r=0.896,0.847,P<0.05);当PIV/VTIPA>1.069或TRV/VTIPA>1.407时,提示PVR>2 Wood单位。结论:多普勒超声技术可以比较准确地估测肺血管阻力。     

Pure word deafness and pure anarthria in a patient with frontotemporal dementia

A 66-year-old right-handed man developed pure anarthria following pure word deafness. In addition to language disorders, his behavior gradually changed and finally included violence against his wife. Brain magnetic resonance imagings revealed atrophy of the left perisylvian area, which included the inferior half of the precentral gyrus and the upper portion of the superior temporal gyrus, consistent with frontotemporal dementia (FTD). It has been documented as either a disorder of expressive language or as an impaired understanding of word meaning. Unlike with pure anarthria, pure word deafness is not included in the clinical diagnostic current criteria for FTD. However, a large variety of language symptoms can appear in FTD according to the distribution of pathological changes in the frontotemporal cortices. This case suggests that pure word deafness could be a prodomal symptom of FTD.     

Cholinergic therapy in dementia

After reviewing the evidence for cholinergic pathology in Alzheimer's disease and related disorders, this paper reviews strategies for treating dementia using cholinomimetic drugs. Special attention is paid to cholinesterase inhibitors, particularly tacrine, the drug recently approved by the FDA. New studies suggesting that muscarinic and nicotinic cholinergic receptor active drugs may be more effective will be reviewed. Brief mention will be made of strategies to slow the progression of Alzheimer's disease.     

SPECT对老年人缺血性脑血管病诊断价值的探讨

本文对21例老年人缺血性脑血管病患者进行SPECT检查,并对SPECT对老年人缺血性脑血管病的诊断价值进行探讨。结果发现SPECT诊断老年人缺血性脑血管病的阳性率为95%,明显高于头颅CT。     

Clinical characteristics of rapidly progressive leuko-araiosis

Introduction – 38 patients found to have either pure leuko-araiosis (LA) or LA combined with infarction(s) on computer tomography (CT) in 1989 were re-examined in 1992 in order to evaluate the progression of LA. The follow-up period averaged 3.2 years. Material and methods - The clinical and radiological data on patients in 1989 were collected from hospital records and re-evaluated. The patients were re-examined clinically (including 24 hour ambulatory blood pressure measurement), and neuroradiologically (CT) in 1992 for this study. Results – 11 (29%) patients were found to have significant (rapid) progression of the extent of LA on CT during the follow-up. At baseline, there was no significant difference in the mean number of brain infarctions between the groups with progressing (prLA) and non-progressing LA (nprLA) or between the number of cortical and central infarctions within these groups. At follow-up, the total number of infarctions had increased significantly in both groups, but it was mostly because of the increase in cortical infarctions in the prLA group (p = 0.043) and, conversely, the central ones in the nprLA group (p = 0.011). prLA was found to be related to heart failure (82% vs 37%, p = 0.029) and atrial fibrillation (55% vs 19%, p = 0.047), whereas nprLA was strongly associated with a sudden onset of symptoms (78% vs prLA 18%, p = 0.001) like a-true brain infarction. Other clinical factors, including mean blood pressure and heart rate, did not clearly differentiate between the groups. Conclusion - The results suggest that there are different subgroups of patients with LA associated with various vascular factors. The occurrence of LA is not related to the distribution of infarctions. The progression of LA is not related to the number of brain infarctions or to the simultaneous increase of infarctions on CT.