Histopathology of BALB/c mice infected with the D variant of encephalomyocarditis virus

BALB/c mice infected with 10(5) pfu of the D variant of encephalomyocarditis virus were examined histopathologically during the subacute stage of infection. Main pathologic changes were observed in the brain, heart (massive myocardial necrosis with subsequent organization (i.e., replacement of necrotic myocardium by connective tissue) and congestion and dilatation of the right ventricle) and pancreas (moderate degranulation of beta-cells resulting in elevation of blood glucose level). The brain lesions were found most frequently in the pyramidal layer of the hippocampus and the granular layer of the cerebellum and were characterized by degeneration of neurons containing virus antigens. Perivascular mononuclear cell infiltration, spreading to the adjacent brain tissue, and thrombosis in small vessels were also frequently seen. Focal loss of neurons and gliosis developed later in these lesions.     

Inhibitory effect of activated protein C on platelet aggregation induced by the prothrombin-converting reaction

The present study was undertaken to elucidate the effect on platelet aggregation of the prothrombin-converting reaction on platelets with or without activated protein C (APC). A reaction mixture of washed platelets from human individuals, Factor Xa and prothrombin markedly induced platelet aggregation; maximum aggregation rates, 31.3–92.5%, and times to reach to maximum aggregation, 11.6 to 20.1 min. This aggregation was inhibited by the addition of APC with 50% inhibition concentration (IC₅₀) value of 14.4 U/ml. APC also inhibited thrombin generation in the reaction mixture in a dose-dependent manner with IC50 value of 0.96 U/ml. However, APC did not inhibit the thrombin (0.1 CU/ml)-induced platelet aggregation at concentrations of up to 30 U/ml. These findings suggest that APC has no direct inhibitory effect on platelet aggregation and that APC inhibits platelet aggregation through inhibition of thrombin generation.     

Crossed cerebellar hypoperfusion in unilateral major cerebral artery occlusive disorders.

We evaluated regional blood flow and oxygen metabolism in the cerebral and cerebellar cortices of 15 patients with unilateral major cerebral artery occlusive disorders with PET. These patients showed a cortical blood flow asymmetry in middle cerebral artery distribution. Only subcortical abnormalities were detected on computed tomography. Nine patients showed crossed cerebellar hypoperfusion, a reduction in contralateral cerebellar blood flow, while six did not. No difference in the degree of cerebral blood flow asymmetry existed between the two patient groups. However, oxygen metabolism asymmetry was more pronounced and was more closely matched to blood flow asymmetry in patients with crossed cerebellar hypoperfusion. These findings suggest that a major cause of cerebral cortical blood flow reduction is reduced metabolic demand in patients with crossed cerebellar hypoperfusion. Crossed cerebellar hypoperfusion may have clinical significance as a reflection of the cerebral metabolic state on blood flow images.     

NPHS1两种新突变蛋白分子的细胞内分布

目的：研究NPHS1两种新突变编码蛋白在细胞内的分布与先天性肾病综合征发病机制的关系。方法：构建野生型和两种突变型NPHS1克隆，并转染至COS7细胞内，应用免疫荧光双标记的方法，分别进行细胞内及细胞表面的荧光标记，通过共聚焦显微镜对裂隙膜分子Nephrin在细胞内的分布进行研究。结果：野生型Nephrin表现为细胞内和细胞膜染色模式；V822M和C265R则主要为细胞内内质网染色模式，细胞膜着色几乎缺失。结论：突变的Nephrin蛋白由于错误折叠，不能由内质网被输送至细胞表面，这可能是先天性肾病综合征发病的机制之一。     

Case of Parkinson's disease presenting with unique dyspneic attacks caused by oromandibular dystonia and sleep apnea syndrome]

A 79-year-old woman with a 4-year history of Parkinson's disease was admitted due to unique dyspneic attacks with cyanosis while eating. Dyspneic attacks with cyanosis occurred mainly during actions such as taking meals or rehabilitation. Due to increased tonus of the orbicularis oris muscle, she was unable to open her mouth and breathe out, and finally experienced hypoxemia as revealed by pulse oxymetry. Dystonic hypertonus was relieved by touching the mandible with the fingers, and she was able to open her mouth again. These symptom was compatible with the sensory trick. Based on these findings, we considered that dyspneic attacks were produced by focal oromandibular dystonia. Polysomnography also showed central sleep apnea. We report herein a rare case of Parkinson's disease presenting with respiratory insufficiency caused by focal dystonia and central sleep apnea.     

Left-side catamenial pneumothorax with endometrial tissue on the visceral pleura.

We present here a rare case of left-side catamenial pneumothorax, in which endometrial tissue pleura was found on the visceral pleura histologically. A chest roentogenogram confirmed the left pneumothorax, but did not reveal bullae or any associated anomalies, in a 41-year-old woman with three documented episodes of left-side pneumothorax occurring every menstruation. Video-assisted thoracoscopic surgery revealed not only tiny holes in the diaphragm, but also a scattered small brown spots on the visceral pleura. Histological examination of the lung sections revealed the existence of endometrial tissue on the visceral pleura with disrupted pleural elastic fibers. Our case suggests that cyclic erosion of the visceral pleura by the implanted endometrial tissue caused air leakage from the lung, in addition to the most accepted concept that air is aspirated into the thoracic cavity via the abdomen through the acquired fenestration of the diaphragm.     

Severely calcified constrictive pericarditis simulating a mediastinal tumor and obstructing the right ventricular inflow tract.

We report a rare case of constrictive pericarditis that stimulated a large mediastinal tumor obstructing the right ventricular inflow tract. A 58-year-old woman was referred to our hospital because of a recent increase of dyspnea and facial edema. Computed tomography revealed severely thickened calcification, including a low-density area, presenting as a mediastinal tumor, compressing the right ventricular inflow tract. A complete resection was performed, and her symptoms dramatically improved. Idiopathic constrictive pericarditis was diagnosed pathologically.     

Acute pulmonary embolism after cerebral infarction associated with a mobile thrombus in the ascending aorta

Although the causes of stroke are diverse, thromboembolism due to a mobile aortic thrombus is rare. We describe a surgical case of acute massive pulmonary embolism after critical cerebral infarction associated with a mobile ascending aortic thrombus in a 52-year-old woman. Concomitant surgical removal of the aortic thrombus and pulmonary embolectomy was performed successfully, and the patient has been stable without recurrent thromboembolic complications after 18 months of follow-up.     

STANDARD IMAGING TECHNIQUES OF ENDOSCOPIC ULTRASOUND‐GUIDED FINE‐NEEDLE ASPIRATION USING A CURVED LINEAR ARRAY ECHOENDOSCOPE

Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented.     

The fates of trichothecene mycotoxins, nivalenol and fusarenon-X, in mice

In order to investigate the comparative fates of nivalenol (NIV) and 4-acetyl derivative of NIV (fusarenon-X, FX) in mice, ³H-FX or ³H-NIV was given p.o. to mice. Radioactivity was excreted mainly via the urine in mice given ³H-FX, but mainly via the feces in mice given ³H-NIV. The plasma radioactivity reached a peak at 30 or 60 min after the administration of ³H-FX or ³H-NIV, respectively. The plasma peak level was 5 times higher, and the area under curve (AUC) was 10 times higher, in ³H-FX-administered than ³H-NIV-administered mice. These findings clearly demonstrate that FX is absorbed from the gastrointestinal tract more rapidly and efficiently than NIV. The HPLC profile of radioactivity of acetonitrile extracts of urine and feces indicated that FX is rapidly metabolized to NIV after being absorbed from the gastrointestinal tract. In vitro incubation of tissue homogenates with ³H-FX demonstrated that the liver and kidney are the organs responsible for the FX-to-NIV conversion. Thus this study demonstrated that the higher oral toxicity of FX than NIV that has been observed in mice and rats is due to the efficient absorption of FX than NIV from the gastrointestinal tract, followed by its rapid conversion to NIV by the liver and kidney.