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1.
The time-course of gastric mucosal surface epithelial cell damage and macroscopically visible lesions in response to restraint and water-immersion stress (22 degrees C) in rats was examined, and the effects on it of 16,16-dimethyl prostaglandin E2 (dmPGE2) were compared with those of papaverine, timoprazole and atropine. The stress produced surface epithelial cell damage prior to visible lesion, the former increasing in severity with time and reaching a plateau 60 min later, by which time exfoliation of surface epithelial cells was observable along the mucosal folds. In contrast, macroscopically visible lesions appeared 2 hr after stress, and severity continued to increase with time. Pretreatment injections (s.c.) of dmPGE2 (3, 30 micrograms/kg), papaverine (100 mg/kg) and atropine (1 mg/kg) protected the surface cells against stress (1 hr)-induced damage, and inhibited visible lesion formation after 4 hr stress. Timoprazole (30 mg/kg, s.c.) did not protect the surface cells, but did markedly inhibit visible lesion formation. dmPGE2, papaverine and atropine, but not timoprazole, inhibited stress-induced increases in gastric contractions. dmPGE2, timoprazole and atropine, but not papaverine, inhibited acid secretion in stress-conditions. These results indicated that stress induced damage to the gastric mucosa within 1 hr due to increased gastric contractions, and the surface epithelial cell damage developed into macroscopically visible lesions in the presence of acid, and that dmPGE2 protected the surface epithelium against stress-induced damage probably by inhibiting gastric contractions.  相似文献   
2.
We operated on a patient who had been paraplegic since sustaining a spinal cord injury 11 years ago. We made a reversed L-shaped sternum incision and cannulated all tubes for the cardiopulmonary bypass through a wound window. This provided an excellent surgical view without restricting the patient's upper limbs (needed for wheel chair operation), and recovery was good. Just after surgery, however, it was difficult to control blood pressure and the loss of serum albumin. We believe this is the first report of open-heart surgery undertaken in a paraplegic patient and that the reversed L-shaped incision and careful monitoring of hemodynamics each played an important role in the successful outcome. We hope that this report will help in the treatment of other paraplegic patients who need open-heart surgery.  相似文献   
3.
The present case report describes a case of ganglioglioma with a distinct sarcomatous component in the left temporal lobe of a 59‐year‐old Japanese man. Neoplastic neuroglial tissue contained both benign and anaplastic glial components with a MIB‐1 labeling index of 0.1% and 12.0%, respectively. Sarcomatous tissue adjacent to the anaplastic glial tissue was dominated by pleomorphic fibroblastic cells with a MIB‐1 labeling index of 10.8%. They were immunoreactive for smooth muscle actin, type IV collagen, and alpha 1 antitrypsin, but not for desmin and CD34. Interestingly, some of the sarcomatous cells were double‐positive for smooth muscle actin and GFAP. The p53 protein had accumulated in the anaplastic astrocytes and sarcomatous cells, but direct DNA sequencing of PCR products failed to detect any mutation in the p53 gene (from exon 4 to exon 10).  相似文献   
4.
Two cases of peritoneal papillary carcinoma are reported. The patient in the first case was a 71-year-old woman with symptoms of obstructive ileus. Laparotomy revealed a tumor in the omentum involving the transverse colon, and several small tumors in the peritoneum and pelvic wall. However, no primary site of the tumor was seen in the ovary, pancreas, or gastrointestinal tract. The patient in the second case was a 44-year-old woman with carcinomatous peritonitis. Postmortem examination revealed multiple tumors in the peritoneum, omentum, and pelvic wall. Tumors were also found in the cortex with mild invasion of the underlying parenchyma of the bilateral ovaries, although these lesions were thought to be metastatic. The histologic features of the tumor in both cases were those of tubulopapillary adenocarcinoma containing scattered psammoma bodies. The cells were positive with the PAS D technique, but negative with alcian blue staining. In both cases, the serum levels of CA-125 were considerably elevated, and the tumor cells showed positivity for CA-125, S 100 protein, cytokeratin and EMA by im-munohistochemistry. The present cases were most likely peritoneal serous papillary adenocarcinoma derived from extraovarian peritoneal mesothelium with miillerian potential, being different from the usual type of diffuse malignant mesothelioma. Acta Pathol Jpn 41: 642-646, 1991.  相似文献   
5.
We studied promoter region polymorphisms in the interleukin (IL)-1alpha, IL-1beta, IL-6, IL-10, tumor necrosis factor, and transforming growth factor (TGF)-beta1 genes in Japanese patients with Alzheimer's disease (AD) (n = 172) and normal controls (n = 163). We also examined an association of a polymorphism located in the glutathione S-transferase omega 1 (GSTO-1) gene region with AD patients. None of these genotypes or allele frequencies showed a significant difference between AD patients and controls. We also failed to detect any difference in the disease onset between each genotype of the seven polymorphisms. Although AD patients carrying high producer alleles of TGF-beta1 and IL-1beta or TGF-beta1 and IL-6 showed a tendency for an early onset of the disease, neither of these combined effects reached a significant level after multiple comparisons. Our findings suggest that genetic polymorphisms in the cytokines and GSTO do not play a major role in Japanese AD patients.  相似文献   
6.
The liver is where lymphocytes undergo activation-induced cell death (AICD) at the resolution phase of an immune response, which is crucial for homeostasis of the immune system and prevention of autoimmunity. Exploring the machinery of AICD in the liver, we found that a primary culture supernatant of murine hepatocytes had an antiproliferative effect on antigen-stimulated T clone and T lymphoma cells. Biological study showed that the antiproliferation was due to induction of apoptosis in a caspase-dependent manner. The apoptosis-inducing potential was sensitive to trypsin, heat (> 70 degrees ) and acid (< pH 5) treatment but could not be neutralized by anti-tumour necrosis factor-alpha, anti-Fas ligand, or anti-transforming growth factor-beta antibodies. Biochemical study of the isolated and purified apoptosis-inducing component from the supernatant showed that it was a protein with a molecular mass of about 68,000-70,000. It induced apoptotic change in murine T and B cells, and to a lesser degree, in human lymphoid cells, but not in macrophages. Biochemical and biological characteristics distinguish this protein from others that have been reported to induce apoptosis of lymphocytes. The identification of an apoptosis-inducing protein derived from murine hepatocytes, which selectively induces apoptosis in lymphocytes, suggests one possible mechanism for immune suppression in the liver.  相似文献   
7.
Time courses of changes in medial gastrocnemius (MG) and soleus (SOL) muscle potentials induced by repetitive stimulation at 5 Hz were studied using Wistar strain rats. Particular interest was focussed on the changing pattern of SOL potentials in old rats as compared with that in young ones. Contrary changing patterns of SOL potentials were found in young and old rats. SOL potentials were rapidly reduced to respective plateau levels in old rats while they were gradually potentiated in young ones when 5 Hz stimulation was given for 10 min. Moreover, the pattern obtained from middle aged rats fell between those of the two age-groups.  相似文献   
8.
OBJECTIVE: Although long-term prostacyclin(PGI2) therapy in patients with severe pulmonary hypertension (PH)reduces pulmonary vascular resistance (PVR), there have been no reports on its therapeutic effects in patients with mild PH. We investigated the chronic effect of beraprost sodium (BPS), an oral PGI2 analog, in children with mild PH. METHODS: We studied 20 patients who were destined for a Fontan procedure with a mean pulmonary arterial pressure(PAP) of>20 mmHg and/or PVR of>3.0 Wood units. Both the PAP and the PVR in these cases were too high for patients to undergo a successful Fontan procedure. Seven patients received BPS (PG group) and 13 did not (control group). All patients underwent repeat cardiac catheterization to examine pulmonary hemodynamics. RESULTS: In the PG group, the pulmonary-to-systemic flow ratio (Qp/Qs) did not change after BPS administration(1.1 +/- 0.6 vs 1.3 +/- 0.9);however, the mean PAP decreased significantly (25.3 +/- 8.2 vs 19.9 +/- 6.5 mmHg; P < 0.05),as did PVR (3.7 +/- 1.3 vs 2.3 +/- 0.9 Wood units; P < 0.05), whereas the pulmonary artery (PA) index increased significantly (312 +/- 136 vs 375 +/- 165; P < 0.05). In the control group, the mean PAP decreased significantly (24.9 +/- 4.7 vs 19.8 +/- 6.3 mmHg; P < 0.05)and the PA index increased significantly (295 +/- 72 vs 362 +/- 114; P < 0.05). No significant changes in Qp/Qs (1.5 +/- 0.8 vs 1.4 +/- 0.6)or PVR (2.9 +/- 1.3 vs 2.5 +/- 0.8 Wood units) were observed. CONCLUSION: We conclude that long-term BPS administration probably reduces PVR in potential candidates for a Fontan procedure with mild PH. This treatment would reduce the risks associated with the Fontan procedure and would also improve its outcome.  相似文献   
9.
The expression of alternatively spliced mRNAs for amyloid precursor protein (APP) isoforms and their translation products were examined in the rat cerebral cortex 1, 3, 6, and 12 h and 1, 3, and 7 days (n = 4-5 in each group) after fluid-percussion brain injury. In situ hybridization studies demonstrated that the expression of APP695 mRNA decreased in and around the damaged area of the cerebral cortex exposed to fluid-percussion injury 1 h after the insult. On the other hand, APP751/770 mRNAs were increased in the regions surrounding the damaged cortical areas 1 day after the injury. An increase of immunoreactive APP was detected in the regions around the damaged cortical areas 3 h after traumatic injury and maintained for the following 3 days. The APP immunoreactivity in the damaged cortices declined to the level of sham-operated animals by post-experimental day 7. Using an anti-amyloid beta (Abeta) protein (17-24) antibody, no deposits of immunoreactive Abeta (17-24) were observed in any of the samples examined in these experiments. These results suggest that the induction of Kunitz-type protease inhibitor (KPI) domain-containing APP mRNAs and the increased accumulation of APP are involved in the physiological and neuropathological responses of brains under various neurodegenerative conditions, including head trauma.  相似文献   
10.
We report a 3-month-old girl with Costelio syndrome complicating fatal hypertrophic obstructive cardio-myopathy. She had typical findings of this syndrome, slight dyspnea and persistent wheezing. Doppler echocardiography revealed asymmetric septal hypertrophy and systolic anterior movement of the anterior mitral leaflet. There was grade 1 mitral regurgitation. Although once her heart failure had been controlled medically, she died suddenly following deterioration of her heart condition. Costelio syndrome can complicate fatal hypertrophic obstructive cardiomyopathy.  相似文献   
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