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71.
The spin-lattice relaxation time (T1) of water protons and the cross-relaxation time (TIS) between irradiated protein protons and observed water protons were measured in order to study water-macromolecular interactions in ischemic rat brain tissues. Tissues were obtained by bilateral common carotid artery occlusion from stroke-prone spontaneously hypertensive rats. Water, Na, and K contents were measured in ischemic brain tissue at the same time. Water and Na content increased while the TIS value and K content decreased following ischemic insults. The T1 value did not change until 180 min after ischemia had been induced. Changes in the TIS value occurred earlier than changes observed for the T1 value, water, and electrolyte contents. Results indicate that the value of TIS may be useful for detecting cerebral ischemia and that the physical structure of water-macromolecular interaction may be altered soon after ischemic onset in brain tissue.  相似文献   
72.
73.
We have previously shown that interleukin (IL)-1beta and tumour necrosis factor (TNF)-alpha mRNA levels in rat alveolar macrophages are increased in by endotoxin (lipopolysaccharide; LPS)- stimulation and further enhanced by culturing with low-Mg2+ medium. We have now investigated the mechanisms of underlying this enhancement by using some specific signal transduction inhibitors. The enhanced elevation of both mRNAs levels was suppressed by pretreatment with TMB-8 (which inhibits calcium release from the endoplasmic reticulum) or dexamethasone (which inhibits nuclear factor [NF]-kappaB and activator protein [AP]-1), but not with verapamil or nifedipine (which inhibits calcium channels). The enhancment of IL-1beta, but not TNF-alpha mRNA levels, was suppressed by pretreatment with W-7 (which inhibits calmodulin), whereas the enhancement of TNF-alpha mRNA levels was suppressed by pretreatment with U73122 (which inhibits phospholipase C). Curcumin (an inhibitor of AP-1), suppressed the increases in both mRNAs induced by low-Mg2+ medium alone, but had no suppressive effect on the levels of either mRNA after LPS-stimulation in low-Mg2+ medium. Pyrrolidine dithiocarbamate (an inhibitor of NF-kappaB) prevented the elevation of TNF-alpha mRNA levels induced by low-Mg2+ medium without LPS-stimulation, but had no suppressive effect on IL-1beta mRNA levels. From these results, we conclude that the enhanced elevation of IL-1beta and TNF-alpha mRNA levels seen in LPS-stimulated alveolar macrophages in low-Mg2+ medium occurs partly via the same, and partly via different, signaling pathways.  相似文献   
74.
Plasma carnitine concentrations in patients undergoing open heart surgery.   总被引:3,自引:0,他引:3  
Carnitine is an essential cofactor for fatty acid (FA) metabolism, the predominant source of ATP in the normal aerobic heart. During myocardial ischemia, FA metabolism is impaired and tissue carnitine levels are depleted. Since the heart cannot synthesize carnitine, plasma carnitine could play an important role in maintaining myocardial carnitine levels during reperfusion. The purpose of this study was to determine the incidence of abnormal plasma carnitine concentrations in open heart surgery. Blood samples were obtained from eleven patients before, immediately after, and two hours after cardiopulmonary bypass (CPB). Total and free carnitine levels were significantly reduced immediately after CPB (p<0.01) and remained depressed until two hours after CPB (p<0.01 vs. pre CPB), while acyl carnitine levels were unchanged over the course of this study. These depressed free carnitine levels might affect cardiac metabolism in the heart after open heart surgery. Carnitine supplement might be a useful adjunct in the therapy after open heart surgery.  相似文献   
75.
We report a 47-year-old alcoholic man with alcoholic pellagra encephalopathy (APE) showing myoclonus and ataxia as chief complaints. He had been a heavy drinker for 30 years. He had noticed appetite loss and subsequently showed a subacutely progressive gait disturbance. He had no history of diarrhea, dementia, or dermatitis. On admission, he showed severe alcoholic liver cirrhosis with a large amount of ascites, limbs and truncal ataxia, myoclonus of the limbs and areflexia, although his consciousness was alert and there were no sign of dermatitis. Though the plasma level of ammonia was normal, we started administration of amino acids suspecting hepatic encephalopathy. Symptoms showed no improvement, and subsequent administration of thiamine was also ineffective. A decreased serum level of niacin was demonstrated. After administration of nicotinamide, the symptoms improved gradually. This patient received a diagnosis of APE. Endemic pellagra, characterized by the classical triad of dermatitis, diarrhea and dementia, is known to be caused by a dietary deficiency of the niacin, and has now become very rare in developed countries. At present, pellagra is encountered most often in patients with chronic alcoholism, which is called APE. APE patients often show only disturbance of consciousness. Although several reports has described ataxia and myoclonus in patients with APE, APE patients with myoclonus and ataxia as chief complaints have not previously been reported. On autopsy cases, central chromatolysis of neurons in the dentate nucleus of the cerebellum, gracile and cuneate nuclei, and the Clarke's column has been demonstrated. The APE patients would show myoclonus and ataxia as their first symptoms. In conclusion, we would like to emphasize that administration of niacin should be started for the treatment of chronic alcoholic patients showing myoclonus and ataxia even without the classical triads found in endemic pellagra patients.  相似文献   
76.
While nonspecific airway hyperresponsiveness (AHR) is a central feature of allergic bronchial asthma, the mechanism underlying the development of AHR is not clearly understood. We have previously demonstrated in vitro hyperresponsiveness of bronchial smooth muscle to acetylcholine (ACh) in rats that were actively sensitized and repeatedly challenged with aerosolized antigen. It has also been demonstrated that the ACh-induced, RhoA-mediated Ca(2+) sensitization is markedly augmented concomitantly with an increased expression and activation of RhoA protein in the bronchial smooth muscle of the antigen-treated rats. In the present study, we have investigated whether TNF-alpha, a proinflammatory cytokine which is involved in bronchial asthma, causes upregulation of RhoA mRNA and protein in the rat bronchus. Treatment of rat bronchial smooth muscle preparations with TNF-alpha (300 ng/ml for 24 hr) significantly shifted the concentration-response curve to ACh upwards, but did not alter the response to high K(+), when compared to that of control tissues. Levels of RhoA mRNA and protein in the TNF-alpha-treated bronchus were significantly greater than those in the control group. In conclusion, it is suggested that the augmentation of the ACh-induced contractile response evoked by TNF-alpha might be mediated by an upregulation of RhoA in rat bronchial smooth muscle.  相似文献   
77.
A 30-year-old female at 27 weeks' gestation, was hospitalized on September 24 1990 because of the premature rupture of the amniotic sac. She underwent Caesarean section on the same day with 700 ml blood loss, but no blood transfusion was required. For several days after the operation, her hemoglobin level remained 7.8 g/dl and did not increase significantly in spite of parenteral iron therapy. On the 9th postoperative day, chills and pyrexia developed with leukopenia. Bone-marrow aspiration revealed severe erythroblastopenia with giant proerythroblasts, suggesting recent HPV infection, which was confirmed by the presence of anti-HPV IgM and HPV antigen by ELISA. The hemoglobin level gradually decreased to 6.0 g/dl by the 21st day, then began to increase rapidly. The serum of acute-phase containing HPV antigens inhibited BFU-E and CFU-E but not CFU-GM. The serum of convalescent-phase inhibited neither erythroid colony growth nor myeloid colony growth. These results indicate that the inhibitory effect of HPV in colony assay is highly specific for erythropoiesis and that HPV play a role in transient cessation of erythropoiesis. The reason, however, for leukopenia in HPV infection remained unclear. This case shows that HPV infection may induce severe hematological disorders even in normal person under erythropoietic stress.  相似文献   
78.
A 54-year-old female presented with subarachnoid hemorrhage due to rupture of a small middle cerebral artery aneurysm, found to be thrombosed at surgery and not visualized on the preoperative angiograms. One major branch of the middle cerebral artery was found to be occluded near the trifurcation. The lumen of the branch proximal to the occlusion had appeared as the aneurysmal opacification on the preoperative angiograms.  相似文献   
79.
A sensitive enzyme-linked immunosorbent assay (ELISA) was used in a retrospective study of placental alkaline phosphatase (PLAP) levels in serum, cerebrospinal fluid (CSF), and intratumoral cyst fluid in primary intracranial germinoma. The ELISA showed no cross-reactivity with intestinal alkaline phosphatase except in very high concentrations, after samples had been heat-treated. Three patients with germinoma were studied for serum PLAP levels and in all the levels were elevated (3.78, 0.52, and 2.11 IU/liter). Two of the germinoma patients were studied for PLAP levels in the CSF, and both had elevated levels (0.83 and 9.83 IU/liter). The intratumoral cyst fluid in one case of germinoma was tested for PLAP and the level was found to be very high (603 IU/liter). These PLAP levels decreased concomitantly with the reduction in tumor size during irradiation. Serum PLAP levels were measured in 40 control adult male individuals and in the CSF of 20 nonpregnant patients with subarachnoid hemorrhage. The upper normal limits were 0.20 and 0.11 IU/liter in the serum and the CSF, respectively. All PLAP levels measured in the serum of patients with various brain tumors were 0.18 IU/liter or less. This study strongly suggests that PLAP is a clinically useful tumor marker for primary intracranial germinoma.  相似文献   
80.
Sialolipoma is a new variant of salivary gland lipoma, which was first proposed by Nagao et al. (Histopathology 2001; 38: 30) in 2001. We report this rare case of sialolipoma in the hard palate. A 60-year-old Japanese woman was referred to our department complaining of a painless swelling on the right side of the hard palate. Intra-oral examination revealed a soft, elastic, dome-shaped mass with 1 cm in diameter located in the posterior part of the hard palate. Magnetic resonance imaging examination revealed high intensity on T(1)-weighted image and isointensity on T(2)-weighted image. Incisional biopsy revealed that the tumor was encapsulated by fibrous tissue, consisted of adipose tissue, and also contained normal salivary gland tissue peripherally. First diagnosed as an ordinary lipoma of the hard palate, the tumor was excised. According to the recent criteria of histologic findings of sialolipoma, we rediagnosed the tumor as sialolipoma of the hard palate.  相似文献   
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