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991.
992.
BACKGROUND: We recently demonstrated that pancreatitis-associated ascitic fluid (PAAF) contains cytotoxic factor(s), inducing apoptosis in hepatocytes, and that PAAF induces hepatic adenosine triphosphate depletion, hepatocellular acidosis, and accumulation of hepatic intracellular sodium. Because ascitic fluid and serum from patients with hemorrhagic pancreatitis contain a lot of hematin, we aimed to test the hypothesis that hematin can induce hepatocellular injury, and then we compared its cytotoxicity with that of PAAF. METHODS: In vivo effects of intraperitoneal injection of hematin into the liver of healthy rats were evaluated with in situ nick-end labeling, blood biochemical analysis, and nuclear magnetic resonance spectroscopy. In vitro cytotoxic and apoptosis-inducing activities of hematin on rat primary culture hepatocytes were investigated with a cellular proliferation assay kit and DNA fragmentation enzyme-linked immunosorbent assay, respectively. Furthermore, PAAF was fractionated with Sephacryl S-300 gel column chromatography, and cytotoxic activities of its fractions on a human hepatoma cell line (HuH-7) were compared with those of hematin. RESULTS: Intraperitoneal injection of hematin into healthy rats caused apoptosis in the hepatocytes and elevated serum glutamate oxaloacetic transaminase and lactate dehydrogenase levels. Intraperitoneal injection of hematin also caused a significant decrease in the hepatic beta-adenosine triphosphate/inorganic phosphate ratio, severe hepatic intracellular acidosis, and a significant increase of hepatic intracellular sodium (Na(+)) concentration, similar to the effects of PAAF. In vitro, hematin decreased hepatocyte viability and increased the DNA fragmentation of hepatocytes, similar to the effects of 10% PAAF. Albumin reversed the cytotoxic effects of hematin and PAAF on HuH-7 cells nearly completely and partially, respectively. Fractionation of PAAF and hematin by gel column chromatography revealed that the first peak of cytotoxic activity of PAAF corresponded to that of hematin and that the cytotoxic activity was reversed by albumin nearly completely. CONCLUSIONS: These results suggest that hematin is one of the cytotoxic factors in PAAF that causes hepatocellular injury and that cellular injuries caused by hematin may be involved in the development of multiple organ failure associated with severe acute pancreatitis.  相似文献   
993.
Abstract: We have simultaneously measured platelet-associated IgG (PAIgG) and megakaryocyte-associated IgG (MAIgG) in 30 untreated patients with chronic idiopathic thrombocytopenic purpura (CITP). Megakaryocytes were purified from bone marrow by 35% Percoll gradient centrifugation, followed by negative immunopanning using magnetic immunobeads. The normal range of MAIgG in 30 healthy donors was 15.5 & 10.0 ng/105 megakaryocytes, whereas MAIgG in the 30 CITP patients was 140 & 59.3 ng/105 megakaryocytes, although the values were widely distributed. From the PAIgG and MAIgG data, CITP patients were classified into three types; type I (PAIgG < 200 ng/107 platelets and MAIgG < 150 ng/105 megakaryocytes), type II (PAIgG > 200 ng and MAIgG > 150 ng), and type III (PAIgG < 200 ng and MAIgG > 150 ng). Patients with types I and III had good clinical courses, but, in contrast, patients with type II responded poorly to steroid therapy followed by splenectomy or became refractory to treatment. In splenectomized patients, MAIgG of responder was promptly decreased to normal range and, in contrast, that of non-responder was persistently elevated. These results indicate that anti-platelet autoantibodies are able to bind with megakaryocytes in the bone marrow as well as with platelets in the peripheral blood, and the results also suggest that megakaryopoiesis in CITP is heterogeneous. Simultaneous measurement of PAIgG and MAIgG may predict the clinical outcome of CIPT.  相似文献   
994.
An exeptional case of Rosai-Dorfman disease (sinus histiocytosis with massive lymphadenopathy) arising from the meninges in a 60-year-old Japanese man is presented. Computerized tomographic scans and magnetic resonance images demonstrated well-circumscirbed tumorous lesions that were homogeneously enhanced with contrast medium. Systemic examination revealed no abnormalities except for a cervical lymphadenopathy and diabetes mellitus. Microscopic examination of the resected specimens showed proliferated histiocytosis and infiltration of plasma cells and lymphocytes. The histology was characterized by the presence of histiocytes demonstrating lymphophagocytosis and immunoreactivity for S-100 protein staining. Immunohistochemical studies and electron microscopy were useful in confirming the diagnosis. The clinical and histopathological features of this disease are discussed.  相似文献   
995.
Several shellfishes including the crab Telmessus acutidens and its prey bivalve Mytilus galloprovincialis were collected at Onahama in Japan to investigate the accumulation of paralytic shellfish poisoning (PSP) toxins during the blooming season of toxic dinoflagellates. The toxicity of the viscera of T. acutidens collected in 1999 was 30.0 and 80.0 MU/g, and that of M. galloprovincialis was 9.6 MU/g by mouse bioassay. PSP toxins in the crab viscera were identified by HPLC-FLD and ESI-MS, so this is the first observation of PSP toxins in T. acutidens. Carbamate toxins (GTX1-4, and STX) were the major component in the crab as well as in the mussels, and accounted for over 60% on a molar basis. However, the ratio of the N1-OH toxin to N1-H toxin of the crabs were largely different from that of the mussels, and a reductive conversion of the toxins in T. acutidens is concluded as the probable cause. In 2000, PSP toxins were also detected in both crabs and mussels, though the contents were very low compared with the levels observed in 1999. The difference in the toxin abundance suggests that the toxin content in the crab was affected by those of the prey.  相似文献   
996.
We found nucleotide variability in the 5'-upstream region and exonic sequences of a gene-encoding canalicular multispecific organic anion transporter/multidrug resistance-associated protein 2 (cMOAT/MRP2) by polymerase chain reaction-based sequencing using genomic DNA from 72 established cell lines derived from 72 Japanese individuals. Four single nucleotide polymorphisms (SNPs) were found in the 5'-untranslational region and 21 in the exonic regions. Of them, 14 were nonsynonymous SNPs. One deletion of seven consecutive adenines resulting in a frameshift variant was also found. Four SNPs, c-24t, g1249a (V417I), c2366t (S789F), and c3972t (I1324I), were the same as those recently reported. A strong association was found between c-24t (5'-untranslated region) and c3972t (exon 28), with the promoter activity of the former worth being compared.  相似文献   
997.
We report a case of a middle-aged man who suffered a cerebral infarction resulting from dissection of a vertebral artery associated with morning blood pressure surge. A 56-year-old man was transferred to our hospital with dizziness and vomiting in the early morning on a cold day in winter. He reported that he had been standing in front of the sink after bathing when he suddenly felt dizzy and fell down. He did not lose consciousness, and by the time he reached the hospital by ambulance, his dizziness had subsided, but he complained of severe headache and vomited 3 times. On admission, he was alert, and there were no neurological or radiological abnormalities (CT, MR angiography) in the brain. However, infarction in the left cerebellar hemisphere was detected by brain MRI on the 5th day of hospitalization. String sign of the left vertebral artery was noted by angiography, confirming the diagnosis of dissection of the left vertebral artery. Ambulatory blood pressure monitoring was performed after discharge. Although the mean 24-h blood pressure was in the normal range, a marked morning blood pressure rise was observed. We speculated that the acute rise of blood pressure in the early morning might have contributed to the dissection of the vertebral artery.  相似文献   
998.
OBJECTIVE: The objective of this study was to identify specific patient satisfaction items related to overall satisfaction by different length of stay (LOS) for patients in Japanese hospital settings. METHODS: This cross-sectional study involved a participant sample, drawn from 77 voluntarily participating hospitals throughout Japan, of in-patients discharged to the community. Older patients and psychiatric, pediatric, obstetric and gynecologic patients were excluded. The 1050 respondents analyzed (response rate > or = 5l.1%) were divided into three groups based on their LOS: group 1, LOS < or = 1 week; group 2, LOS < or = 1 month; and group 3, LOS > 1 month. Using stepwise multiple regression analysis, we explored for each LOS group the relationship between overall patient satisfaction and satisfaction with 33 individual items, including three regarding perceived reputation of the hospital in question. RESULTS: Some unique satisfaction items for each group (e.g. 'skill of nursing care' in group 1, 'Recovery of physical health', 'skill of nursing care', and 'respect for patients opinions and feelings' in group 2, and 'relief from pain' and 'respect for patients' opinions and feelings' in group 3) were significantly associated with overall satisfaction. In all three groups, common items (e.g. 'recovery from distress and anxiety' and 'doctor's clinical competence') also related significantly to overall satisfaction. Two items pertaining to the hospital reputation dimension (e.g. 'family member's evaluation of the hospital' and 'hospital reputation among other patients') were also significant predictors of overall satisfaction in all three groups. CONCLUSION: The findings show that according to LOS, unique items could determine significantly the achievement of overall satisfaction, while some common predictors across all three LOS groupings also seemed to be indispensable for inpatient's assessment of hospital care. It was also confirmed in this study that a positive perception of hospital reputation might have an important role in patient satisfaction in Japan.  相似文献   
999.
1000.
We present a rare case of a solitary dumbbell intra- and extramedullary schwannoma of the thoracic spine in a 54-year-old man without signs of von Recklinghausen's disease. The patient presented with motor weakness in the left lower extremity, bilateral sensory impairment below the T9 dermatome and rectovesical dysfunction. Preoperative magnetic resonance imaging was suspicious for an intradural extramedullary tumor. At operation, the tumor was located posteriorly, at the midline, with no relationship to the posterior nerve roots and was firm and adherent to the adjacent spinal cord, which surrounded the intramedullary portion of the tumor. The intramedullary mass was completely removed with sharp dissection after removal of the extramedullary mass. Surgery resulted in minimal postoperative neurological deficits. These tumors may arise from the Schwann cells of the nerve plexus surrounding vessels in the posterior median sulcus and thus may grow in both an intra- and extramedullary fashion. The optimal treatment of these schwannomas is total removal.  相似文献   
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