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The effect of intravenous infusion of 10% glycerol on polymorphic delta waves of EEG was investigated in 13 patients (15 studies) with brain tumors in cerebral hemisphere. The delta waves were analyzed by two-dimensional EEG topography and power spectrum of delta waves (P(delta)) over the tumor, adjacent, and distant regions in the same hemisphere to the tumor, and ipsi- and contralateral hemispheres to the tumor. The data focus of EEG topography was well corresponded to the tumor and surrounding brain edema which visualized by x-ray CT-scan. In the patient with brain tumors with marked brain edema (group A, 11 studies), EEG topography showed marked reduction of delta focus within 20 minutes from the end of intravenous infusion of glycerol, and returned to preinfusion distribution within 60 minutes. In patients with absent to minimum brain edema (group B, 4 studies), delta focus showed the tendency to enlarge and returned to preinfusion state at 60 minutes after the end of glycerol infusion. In patients of group A, P(delta) of ipsilateral hemisphere to tumor decreased at the end of glycerol infusion, and showing maximal reduction ratio (30%, p less than 0.01) at 20 minutes, re-increased there-after. In group B, P(delta) of ipsilateral hemisphere showed no definite changes after the glycerol infusion. P(delta) of contralateral hemispheres in patients of both group A and B, showed similar reduction ratio and time course to those of ipsilateral hemisphere of group A.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
MCP-1-dependent signaling in CCR2(-/-) aortic smooth muscle cells   总被引:1,自引:0,他引:1  
Monocyte chemoattractant protein-1 (MCP-1, CCL2) is a mediator of inflammation that has been implicated in the pathogenesis of a wide variety of human diseases. CCR2, a heterotrimeric G-coupled receptor, is the only known receptor that functions at physiologic concentrations of MCP-1. Despite the importance of CCR2 in mediating MCP-1 responses, several recent studies have suggested that there may be another functional MCP-1 receptor. Using arterial smooth muscle cells (SMC) from CCR2(-/-) mice, we demonstrate that MCP-1 induces tissue-factor activity at physiologic concentrations. The induction of tissue factor by MCP-1 is blocked by pertussis toxin and 1,2-bis(O-aminophenyl-ethane-ethan)-N,N,N',N'-tetraacetic acid-acetoxymethyl ester, suggesting that signal transduction through the alternative receptor is G(alphai)-coupled and dependent on mobilization of intracellular Ca(2+). MCP-1 induces a time- and concentration-dependent phosphorylation of the mitogen-activated protein kinases p42/44. The induction of tissue factor activity by MCP-1 is blocked by PD98059, an inhibitor of p42/44 activation, but not by SB203580, a selective p38 inhibitor. These data establish that SMC possess an alternative MCP-1 receptor that signals at concentrations of MCP-1 that are similar to those that activate CCR2. This alternative receptor may be important in mediating some of the effects of MCP-1 in atherosclerotic arteries and in other inflammatory processes.  相似文献   
4.
We report on an 11 year old girl with trichorhinophalangeal syndrome type I (TRPS1), postaxial polydactyly of the fingers, and a de novo paracentric inversion on the long arm of chromosome 8 involving bands q13.1 and q24.11. Molecular analysis using FISH and polymorphic DNA markers detected an approximately 4 Mb, cytogenetically unidentified deletion occurring between two STSs markers, AFMB331YA9 and D8S1200, around the region of the distal inversion breakpoint. Although the deletion is large, mental retardation was not present in the patient. This is the first report of a cryptic deletion in a TRPS1 patient, both ends of which were analysed at the molecular level. The data obtained are useful for defining the location of the putative mental retardation gene(s) in TRPS1 and Langer-Giedion syndrome (TRPS2), as well as a locus for postaxial polydactyly.  相似文献   
5.
The mechanism underlying the regulation of the K-channel by the muscarinic receptor was examined with patch-clamp experiments in atrial cells isolated enzymatically from the rabbit heart. The patch-electrode and the recording chamber were perfused with various solutions while the activity of the K-channels in the membrane-patch was recorded continuously. In the absence of muscarinic agonists, opening of K-channels occurred at a low frequency (basal activity). Application of ACh to the bath did not affect the basal activity, but perfusion of the patch electrode with ACh markedly increased the channel activity in the "cell-attached" patch. Application of oxotremorine, i.e. a specific muscarinic agonist, via the pipette also opened K-channels. When the membrane patch was isolated from the cell body ("inside-out" patch), ACh-induced single K-channel currents were still observed, but the frequency was reduced. Perfusion of atropine or scopolamine, two muscarinic antagonists, through the patch-electrode depressed the basal activity. In the case of scopolamine, channel-activity recovered after washing out the drug. The current voltage relationship determined from the basal activity was similar to that of ACh-induced single K-channel currents. The mean open time was 0.49 ms at basal activity and 1.35 ms during the application of 0.1 microM ACh via the patch electrode. Application of oxotremorine via the pipette hardly affected the open-time, it remained at 99 +/- 4% (n = 7) of the control.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Proteins of Chlamydia pneumoniae immunodominant in humans were characterized with the sera of 13 patients who were not likely to have been exposed to C. trachomatis or C. psittaci. The serological responses among these patients were similar on a qualitative basis, but some differences were found quantitatively. However, the serological responses of the patients who were infected with C. pneumoniae differed markedly from those of two patients who were infected with C. trachomatis and two who were infected with C. psittaci and those of mice that were transtracheally infected with C. pneumoniae. Among proteins immunodominant in the patients who were infected with C. pneumoniae, a 40-kDa major outer membrane protein was genus specific and 53-, 46-, and 43-kDa proteins were species specific in their reactions with the majority of the human sera used. A few sera reacted strongly with a 73-kDa protein genus specifically. Some proteins with weak immunogenicity exhibited species specificity. An antigenic analysis with human sera and murine monoclonal antibodies against the 53-kDa protein showed that hte antigenicities were strictly conserved among the seven strains of C. pneumoniae tested. The genus-specific 73-kDa protein was solubilized with octylglucoside. All of the species-specific immunodominant proteins were solubilized with sodium dodecyl sulfate, but the genus-specific major outer membrane protein was not. These results suggest that a serological diagnosis of C. pneumoniae infection could be achieved species specifically by comparison of the serum responses to sodium dodecyl sulfate- and octylglucoside-soluble fractions.  相似文献   
8.
Background/Objective: The feces sign has been reported as a possible predictive factor for non-operative treatment of small bowel obstruction. However, its relationship with prognosis of non-emergency adhesive small bowel obstruction remains unclear. This study aimed to clarify the relationship between the feces sign and prognosis of non-emergency adhesive small bowel obstruction.MethodsNinety-two patients with non-emergency adhesive small bowel obstruction with the transitional zone visible on computed tomography were included. Patients were categorized into two groups: feces sign positive (n = 40) and negative (n = 52). Clinical features and prognosis were compared between the two groups. Cox proportional hazards regression models incorporating the feces sign were used to analyze odds of diet resumption and discharge.ResultsPatients with feces sign were younger (p = 0.015), had a higher body mass index (p = 0.027), and a lower white blood cell count (p = 0.019) on admission. More patients with feces sign were successfully treated with fasting and/or nasogastric tube placement (p < 0.001), and no patient with feces sign suffered from recurrent obstruction after diet resumption. Kaplan–Meier analysis showed that patients with feces sign took less time for diet resumption (p = 0.007) and discharge (p = 0.004) than those without it. Using Cox proportional hazards regression model, the feces sign was reported as an independent predictor of diet resumption (odds ratio 1.685, p = 0.018) and discharge (odds ratio 1.861, p = 0.007).ConclusionsThe feces sign is associated with improved odds for diet resumption and discharge.  相似文献   
9.
BACKGROUND: Persistent hypoalbuminemia is a long-term poor prognostic factor in chronic hemodialysis patients. PATIENTS AND METHODS: We investigated the correlation between the degree of peroxidation of erythrocyte membrane lipids, erythrocyte alpha tocopherol content, erythrocyte glutathione peroxidase activity and serum albumin concentration in twelve patients with uremia not undergoing hemodialysis and fifteen patients on maintenance hemodialysis. RESULTS: The glutathione peroxidase activity in erythrocytes was higher in patients of uremia not undergoing hemodialysis than in chronic hemodialysis patients. A significant negative correlation was observed between the erythrocyte alpha tocopherol content and the degree of erythrocyte membrane lipid peroxidation in chronic hemodialysis patients. There was a statistically significant difference in the degree of erythrocyte membrane lipid peroxidation between patients with chronic hemodialysis-associated hypoalbuminemia and chronic hemodialysis patients having normal serum albumin levels. CONCLUSION: This study suggested that serum albumin inhibits peroxidation of erythrocyte membrane lipids and that hemodialysis induces recovery of serum reductivity. We conclude that persistent hypoalbuminemia worsens the serum antioxidant activity in chronic hemodialysis patients and may contribute to increased oxidative cell damage.  相似文献   
10.
We studied the significance of N-acetyl--glucosaminidase (-NAG) and type III procollagen peptide (P-III-P) in the effluent of rodent hepatic grafts. After total hepatectomy, the livers were preserved in chilled, lactated Ringer's solution and then divided into five groups (n=10 each): group 1, 4 h preservation only; group 2, 4 h preservation and rewarming; group 3, 6 h preservation only; group 4, 6 h preservation and rewarming; and group 5, minimal preservation only. The -NAG of groups 2 and 4 was significantly higher than that of groups 1 and 3 (0.98±0.5 U/l vs 0.21±0.12 U/l; P<0.01 and 1.76±0.67 U/l vs 0.38±0.25 U/l, respectively; P<0.01), while that of group 4 was significantly higher than that of group 2 (1.76±0.67 U/l vs 0.98±0.50 U/l; P<0.05). The P-III-P of group 4 was significantly higher than that of group 2 (0.133±0.008 U/ml vs 0.110±0.015 U/ml; P<0.01). We conclude that -NAG is a novel parameter of parenchymal and nonparenchymal cells, while P-III-P reflects the integrity of the hepatic sinusoidal extracellular matrix.  相似文献   
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