Computed tomographic changes of the brain and clinical outcome of patients with seizures and epilepsy after an ischaemic hemispheric stroke.

It is not well established whether seizures and epilepsy after an ischaemic stroke increase the disability of patients. Seventy-two patients with delayed seizures after a hemispheric infarct (37 with a single seizure and 35 with epilepsy) were included in the study. The modified Rankin scale was used to compare disability of the patients at 1 month after stroke and at 2 weeks after single or the last seizure, in case of epilepsy. The size of the X-ray hypoattenuation zone was compared on computed tomographic (CT) scans, performed in the weeks after the stroke and 1 week after single or repeated seizures. Lesion size was determined by superimposing the CT slices on digital cerebral vascular maps, on which the contours of the infarct area were delineated. The extent of the infarcts was expressed as the percentage fraction of the total surface area of the cerebral hemisphere. Groups with a single seizure and with epilepsy were mutually compared. Infarcts predominated in the parieto-temporal cortical regions. In the overall group the median Rankin score worsened significantly after seizures. The average size of the X-ray hypoattenuation zone was also significantly increased on the CT scans after the seizures, compared with those after stroke, without clear evidence of recent infarction. Mutual comparison of patients with a single seizure episode and of those with epilepsy showed only a trend of more severe disability and of increase in lesion size in the post-stroke epilepsy group. Delayed seizures and epilepsy after ischaemic stroke are accompanied by an increase in lesion size on CT and by worsening of the disability of the patients. This study does not allow to determine whether this is due to stroke recurrence or due to additional damage as a result of the seizures themselves.     

胃癌的危险因素调查及癌前病变动态观察

报道温州地区胃癌高发区瑞安塘下的致癌危险因素的调查情况,结果表明它是由多种致癌危险因素的综合影响。作者应用内镜活检在18000例慢性胃病患者中查出癌前病变(高危人群)1132例,经3月～14年活检随访,表明胃癌前病变有一定的可逆转性;癌变率较高的是胃溃疡(GU)+不典型增生(ATP)组、GU+慢性萎缩性胃炎(CAG)组及CAG+ATP组均为4.1％;总癌变率为3.1％。早癌检出率占胃癌总数的48.6％,为门诊早癌检出率的6.8倍。此方法简单、经济实用。     

Computed tomographic findings in cerebral toxoplasmosis in adults

The clinical and computerized tomographic (CT) findings in 10 patients with cerebral toxoplasmosis are reviewed. All patients with cerebral toxoplasmosis were homosexuals and/or intravenous drug users, and all patients had other manifestations of AIDS. Two presented with focal seizures, 4 presented with focal neurological deficit which progressively worsened, and 4 had evidence of diffuse neurological dysfunction (altered consciousness, generalized seizures). CT showed a single lesion in 3 patients and multiple lesions in 7 patients. Two patients had hypodense nonenhancing lesions(s). Eight patients had hypodense lesions with peripheral or nodular enhancement. The lesions were more commonly located in the cerebral hemispheres and subcortical gray matter nuclear masses (thalamus, basal ganglia). The finding of a hypodense lesion with a central slightly hyperdense noncalcified region that showed dense nodular homogeneous enhancement was quite characteristic of cerebral toxoplasmosis, but this pattern may also be seen in other neurological conditions including brain lymphomas.     

Counter Intuitive Relations Between in vivo RF Lesion Size, Power, and Tip Temperature

Background: Radiofrequency (RF) lesion size in vitro is positively correlated with applied power and catheter tip temperature. However, the relation between RF lesion size, power, and tip temperature in vivo remains unclear. We hypothesized that due to flow, anatomy and tip contact effects in vivo, increased tip temperature would be inversely related to applied power and RF lesion size. Methods: RF lesions were created on the endocardium of 16 pigs using 5, 6, and 7 Fr catheters. The ablation generator was set to achieve a temperature of 70°C. RF lesions were created in different regions of the heart so as to encompass a wide range of blood flow and catheter movement conditions. RF lesions were measured acutely (DIMEN, mm) and correlated with average power applied (POWER, W), and average tip temperature (TEMP, °C). The POWER and TEMP relation was also examined. Results: For TEMPs below 55°C, the power output from the generator was typically maximized at 50 W. At TEMPs above 55°C, POWER decreased exponentially with increasing TEMP {POWER = 50 – exp(-((41-TEMP)/7)), r = 0.98, p < 0.05}. Further, DIMEN tended to be inversely related to TEMP (Slope: –0.07 ± 0.04, r = –0.15, p = 0.07); but, was positively related to POWER (Slope: 0.04 ± 0.02, r = 0.23, p < 0.05). These relations varied by tip size and estimated local blood flow characteristics. Conclusion: In vivo, variable tissue contact and flow yield DIMEN-POWER-TEMP relations opposite to those found in vitro. These counterintuitive results suggest that maximum in vivo RF lesion size is achieved when power is maximized at tip temperatures between 50 and 60°C.     

Binswanger's disease in the absence of chronic arterial hypertension

Summary The cerebral changes are described in a woman of 54 who suffered from Binswanger's encephalopathy: there were no signs or symptoms of chronic arterial hypertension. The disease presented as dementia of about 3 years duration. Computed tomography of the brain 2. 5 years before her death showed bilateral widespread hypodense lesions in the cerebral white matter. She died of an asthmatic attack. Autopsy disclosed extensive bilateral degeneration of the central white matter, lacunes and gliosis. Severe obliterative arteriolosclerosis occurred in the meningeal vessels and those supplying the affected parts of the brain. Light microscopy showed that the most severe lesions occurred in the arterioles. Immunohistochemistry demonstrated profound extravasation of plasma proteins chiefly albumin, indicating dysfunction of the blood-brain barrier. Thus, the lesions characteristic of Binswanger's encephalopathy may develop in the absence of chronic arterial hypertension. Additional pathogenic factors, possibly genetic predisposition to vascular injury may play a role in the development of this condition.Supported by grants from the Swedish Medical Research Council, Project No 12X-03020 and 1987 Års Stiftelse för Strokeforskning     

Neural plasticity in vivo: opioid sensitivity of memory develops gradually after a septal lesion

Neuronal plasticity can manifest itself in alterations in the sensitivity of memory to the effects of drugs. After the production of a brain lesion, the memory processing of a passive-avoidance task in mice gradually becomes sensitive to the effect of morphine, i.e., an improvement in retention performance is seen after 6 weeks, but not after 1 or 2 weeks. The results presented demonstrate that, even if they lead to no discernible changes in behaviour, plastic processes can still be detected by means of behavioural tests.     

易误诊为神经肿瘤的一种疾病——肿块型中枢神经系统原发性血管炎

背景与目的：由于缺乏特异性临床和影像表现，肿块型中枢神经系统原发性血管炎（primary angiitris of central nervous system，PACNS）常被误诊为胶质瘤．本文旨在探讨肿块型PACNS的诊断与鉴别诊断。方法：回顾性分析手术治疗的37例肿块型PACNS患者的临床及影像表现。结果：85．3％的患者出现局灶性神经功能减退，55．9％患者有不同程度皮层高级功能减退症状。70．6％的颅内病变累及脑皮层：73．5％患者的正常区域脑血管周围间隙增宽，其中76％出现血管强化；病变出现特征性的“C”形强化。结论：局灶性神经功能和高级功能减退、病变累及皮层和“C”形强化等特征．有助于诊断肿块型PACNS。     

Carcinoma of the thyroid in black patients.

In the period from January 1, 1976 to December 31, 1988, we reviewed the charts of 33 patients treated for carcinoma of the thyroid at Howard University Hospital. The three non-black patients (two Whites and one Pakistani) were excluded from the study. There were 19 females and 11 males. Of the 30 cases elevated, 10 were papillary, 7 were follicular variant of papillary, 8 were follicular, 3 were undifferentiated (anaplastic), and 2 were medullary. Ten patients had either distant metastasis (Hoffman, South Med J 80:741, 1987) or locally advanced disease in the neck (Woolner et al., Am J Surg 102:354, 1961.) at the time of diagnosis. The treatment of these lesions depended on, among other variables, the cell type, the extent of the lesion, and the personal preference of the attending surgeon. Carcinoma of the thyroid remains an uncommon lesion in Black patients. Because of its rarity, the diagnosis may often be delayed and, as a result, patients may first come to attention with a more advanced stage of this disease. To prevent this occurrence, a high index of suspicion must be maintained for all thyroid nodules, and appropriate diagnostic steps taken. Diagnostic and treatment options are discussed.     

The bactericidal activity of pulsed Nd-YAG laser radiation in vitro

Pulsed Nd-YAG laser irradiation of bacteria has been suggested as a possible means of treating contaminated intra-oral sites although relatively few studies have been conducted. In this investigation, the antimicrobial activity of a pulsed Nd-YAG laser was assessed in vitro for a range of oral bacteria using several pulse energies and exposure durations. Pure cultures of each organism were lased in saline suspensions followed by standard colony counting techniques for test and control samples. Microbial inhibition was found to be organism-dependent and varied with energy dose and pulse energy. For all nine test species 120-mJ laser pulses proved more efficient than 80-mJ pulses, with 99.9% kills compared with around 90% kills after exposure to 1800 pulses. These killing activity levels compare favourably with those achieved with other lasers in vitro.     

组织工程化口腔粘膜的构建技术初步研究

目的　探索组织工程化口腔粘膜的构建方法。方法　用 Dispase中性蛋白酶分离提取未长毛的 SD乳鼠硬腭口腔粘膜细胞 ,用角化细胞培养液对口腔粘膜细胞进行培养 ,以自制藻酸钠薄膜作为支架材料构建组织工程化的口腔粘膜。结果　 Dispase中性蛋白酶可较好地分离提纯口腔粘膜细胞 ,用 Dispase消化酶分离获取上皮后 ,再用胰蛋白酶消化上皮为单细胞的最佳时间为 10 m in,过低的细胞密度不易形成克隆 ,鼠口腔粘膜细胞培养的最适密度为 1.5× 10 5/ cm2 。角化细胞培养液能对鼠口腔粘膜细胞进行培养 ,且没有成纤维细胞污染 ;口腔粘膜细胞在藻酸钠薄膜上生长良好。结论　利用角化细胞培养液作为培养基 ,藻酸钠薄膜作为支架材料可成功构建组织工程化口腔粘膜