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.     

Nerve conduction and microanatomy in the rabbit sciatic nerve after gradual limb lengthening-distraction neurogenesis.

To clarify how the peripheral nerve adapts to elongation during gradual limb lengthening, electrophysiological and histomorphometric examinations were performed on the sciatic nerves in 18 rabbits. External fixators were used to lengthen the right femora by 30 mm (30%), at a daily rate of 0.5 mm (Group 1) or 2.0 mm (Group 2). Examinations were performed immediately after the limb lengthening procedure. Electrophysiologically, mild conduction slowing was observed in Group 1; a conduction block was evident in Group 2. Histologically, the mean diameter of myelinated fibers was unchanged in Group 1, but a significantly decreased diameter was observed in Group 2. Electron microscopy revealed that mild degenerative change of unmyelinated axons occurred sporadically in two cases in Group 2, but neither group showed evidence of thinning of myelin sheath of myelinated fibers. The mean internodal length (between nodes of Ranvier) of teased fibers was 1216+/-295 microm in the control contralateral side, 1484+/-347 microm in Group 1, and 1467+/-322 microm in Group 2. Thus the internodes were lengthened by 22.1% (Group 1) and 20.7% (Group 2) in comparison with those of the controls. Straightening of the geometry of paranodal myelin sheath was significantly correlated with the rate of distraction. These results indicate that myelinated nerve fibers adapt to gradual elongation by lengthening each Schwann cell body, not by proliferation of Schwann cells.     

Lack of biliary excretion of Cd linked to an inherent defect of the canalicular isoform of multidrug resistance protein (cMrp) does not abnormally stimulate accumulation of Cd in the Eisai hyperbilirubinemic (EHB) rat liver

A new mutant, the Eisai hyperbilirubinemic (EHB) rat, shows no inherent expression of the canalicular isoform of the multidrug resistance protein (cMrp) in the liver. It has defective biliary secretion of organic anions such as bilirubin glucuronides, bromosulfophthalein (BSP), cysteinyl leukotrienes, glutathione (GSH) and bile acid sulfate and glucuronides. When rats were injected intravenously with CdCl₂, biliary excretion of Cd over 30 min was 0.28% and 0.004% of the total dose in Sprague-Dawley (SD) and EHB rats, respectively. Six SD rats and five EHB rats were fed a diet containing Cd. Bile Cd was detected at the level of 2 ng/20 min in SD rats, but not in EHB rats. There was no significant difference of hepatic Cd concentration between SD and EHB rats. Furthermore, there were no significant differences of renal and intestinal Cd, and hepatic and renal metallothionein (MT) concentrations between the SD and EHB groups. Biliary excretion of reduced-GSH for 20 min was 1.3 ± 0.3 mg and 3.6 ± 0.9 μg in SD and EHB rats, respectively. Our results suggest that hepatobiliary excretion of exogenous Cd is mediated mainly via carrier transport, including a cMrp or GSH carrier, but that the lack of the transport pathway does not contribute to abnormal accumulation of Cd in the liver. Received: 12 August 1996 / Accepted 7 November 1996     

Silicone-Coated Polypropylene Hollow-Fiber Oxygenator: Experimental Evaluation and Preliminary Clinical Use

Background. A membrane oxygenator consisting of a microporous polypropylene hollow fiber with a 0.2-μm ultrathin silicone layer (cyclosiloxane) was developed. Animal experimental and preliminary clinical studies evaluated its reliability in bypass procedures.

Methods. Five 24-hour venoarterial bypass periods were conducted on dogs using the oxygenator (group A). In 5 controls, bypass periods were conducted using the same oxygenator without silicone coating (group B). As a preliminary clinical study, 14 patients underwent cardiopulmonary bypass with the silicone-coated oxygenator.

Results. Eight to 16 hours (mean, 12.2 hours) after initiation of bypass, plasma leakage occurred in all group B animals, but none in group A. The O₂ and CO₂ transfer rates after 24 hours in group A were significantly higher than at termination of bypass in group B (p < 0.005 and p < 0.03, respectively). Scanning electron microscopy of silicone-coated fibers after 24 hours of bypass revealed no damage to the silicone coating of the polypropylene hollow fibers. In the clinical study, the oxygenator showed good gas transfer, acceptable pressure loss, low hemolysis, and good durability.

Conclusions. This oxygenator is more durable and offers greater gas transfer capabilities than the previous generation of oxygenators.