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1.
OBJECTIVE: To predict spinal cord ischemia after endovascular stent graft repair of descending thoracic aortic aneurysms, temporary interruption of the intercostal arteries (including the aneurysm) was performed by placement of a novel retrievable stent graft (Retriever) in the aorta under evoked spinal cord potential monitoring. METHODS: From February 1995 to October 1997, endovascular stent graft repair of descending thoracic aortic aneurysms was performed in 49 patients after informed consent was obtained. In 16 patients with aneurysms located in the middle and distal segment of the descending aorta, the Retriever was placed temporarily before stent graft deployment. The Retriever consisted of two units of self-expanding zigzag stents connected in tandem with stainless steel struts. Each strut was collected in a bundle fixed to a pushing rod, and the stent framework was lined with an expanded polytetrafluoroethylene sheet. The Retriever was delivered beyond the aneurysm through a sheath and was retracted into the sheath 20 minutes later. A stent graft for permanent use was deployed in patients whose predeployment test results with the Retriever were favorable. Evoked spinal cord potential was monitored throughout placement of the Retriever and stent grafting until the next day. RESULTS: The Retriever was placed in 17 aneurysms in 16 patients. There were no changes in amplitude or latency of evoked spinal cord potential records obtained before or during Retriever placement. After withdrawal of the Retriever, all aneurysms were excluded from circulation immediately after permanent stent grafting. There were no changes in evoked spinal cord potential, nor were neurologic deficits seen after stent graft deployment in any patient. CONCLUSIONS: These results suggest that predeployment testing with the Retriever under evoked spinal cord potential monitoring is promising as a predictor of spinal cord ischemia in candidates for stent graft repair of thoracic aortic aneurysms.  相似文献   

2.
Mimics recapitulating the structural features of tRNAs are involved in biological processes other than ribosome-dependent protein synthesis. A knowledge of the rules underlying the architecture and function of tRNAs allows the design of non-natural mimics. The study of these mimics sheds light upon links between replication, translation and metabolic pathways, leads to biotechnological applications, and provides experimental and conceptual tools for the exploration of primordial evolutionary processes.  相似文献   

3.
Phagocytosis represents a powerful stress for the phagocytic cells. Phagocytosis of Staphylococcus aureus induces a stress response associated with the synthesis of specific heat shock/stress proteins (HSP). Here we investigated the stress response of human monocyte-macrophages (m phi) to Pseudomonas aeruginosa, a bacterium found, as for S. aureus, in the airways of patients suffering cystic fibrosis. P. aeruginosa activated in m phi the production of both extra- and intracellular O2-; increased Interleukin-1 beta and actin, but failed to induce host HSP. Neither S. aureus' exotoxins nor the scavenging property of P. aeruginosa's alginate, but the lower toxicity of P. aeruginosa and/or differential activation of proteine kinase C (PKC) by the two bacteria, might explain their differences in host HSP induction. While O2- is insufficient to induce HSP synthesis in m phi, hydroxyl radicals, generated in the presence of exogenous iron, is a likely additional signal, along with PKC activation, for HSP induction during bacterial phagocytosis.  相似文献   

4.
1. The synthesis of heat shock protein 70 (Hsp70) mRNA and the expression of Hsp70 in the liver of broiler chickens submitted to acute heat stress (35 degrees C for 5 h) was investigated. 2. Hsp70 expression was detected by SDS-PAGE and Western blot analysis using a polyclonal antiserum against Hsp70 of Blastocladiella emersonii. The specific signal of Hsp70 mRNA was analysed by Northern blot using as probe a Hsp70 cDNA of B. emersonii. 3. An increase in the amount of Hsp70 was detected from the first up to the fifth hour of acute heat exposure. This increase in the amount of Hsp70 was accompanied by an increase in Hsp70 mRNA which peaked at 3 h. 4. This study shows that the heat induced increase in Hsp70 mRNA and protein in broiler liver, in vivo, are time dependent, similar to that in mammals.  相似文献   

5.
6.
Cyclophosphamide (CP) is a widely used antineoplastic drug. It tests positive in several genotoxicity assays, including those with endpoints such as chromosomal aberrations in mammalian cells, mitotic recombination in Drosophila melanogaster, and dominant lethal mutations in rodents. We have explored the effects of CP on genome stability of mouse (Mus domesticus) spermatogenic cells, using a recombination-based transgenic assay called MUSCATEER. In this system, intrachromosomal gene conversion events between two mutually defective lacZ genes generates beta-galactosidase activity in spermatids. The frequency of gene conversion events is determined by scoring spermatids stained with the lacZ substrate, X-gal. A dose-dependent induction of lacZ-positive spermatids was observed following single intraperitoneal CP exposures of 10, 100, and 200 mg/kg. At 200 mg/kg, there was a 25-fold increase over baseline. Treatment of a control transgenic line containing only a frame-shifted lacZ transgene provided an indication that CP also induced reversion mutations. The timing of the response indicated that the induction of recombination and/or mutation occurred primarily in meiotic stage cells. These results demonstrate potent germline mutagenicity of CP, and validate the utility and sensitivity of genetic recombination as a rapid indicator of genotoxicity in whole animals.  相似文献   

7.
Heat shock proteins are induced by several stress factors and are potential antigens in autoimmune disorders. Expression of heat shock protein 90 (HSP 90) was investigated in patients with inflammatory bowel disease and normal controls. We combined western blot analysis with laser densitometry for quantitation. Localization of HSP 90 was investigated by immunohistochemistry. Western blots showed a significant mucosal expression of HSP 90, which was comparable in patients and controls. There was also no difference between normal and inflamed mucosa in inflammatory bowel disease. In immunohistochemical staining studies, HSP 90 was detected in epithelial cells, mononuclear cells, giant cells, nerve cells, and endothelial cells of small vessels. There was no difference in the intensity of staining or localization in patients with inflammatory bowel disease compared to controls. These findings render a potential protective or immunogenic function of HSP 90 in inflammatory bowel disease unlikely.  相似文献   

8.
Increased heat shock protein expression after stress in Japanese quail   总被引:1,自引:0,他引:1  
The health care received from first admission to a pediatric rheumatology clinic to 9-year follow-up was assessed in 109 patients with chronic inflammatory rheumatic diseases or chronic idiopathic musculoskeletal pain. Ninety-five of the patients had received hospital care after the first admission, of whom 53 patients > or = 18 years, 21 patients < 18 years, and 33 parents of patients < 18 years rated their degree of satisfaction with the health care from 0 to 10. Mean scores of satisfaction with different aspects of care ranged from 6.0 to 9.6. Among patients > or = 18 years, those with idiopathic pain were less satisfied than those with inflammatory rheumatic diseases on the availability of care (mean 6.4 vs. 8.5, p < 0.001), continuity of care (mean 6.5 vs. 8.4, p < 0.001), and empathy of the health care providers (mean 6.7 vs. 7.9, p <0.05). The diagnostic group and the occurrence of remission predicted the level of global satisfaction in patients > or = 18 years. In patients < 18 years, chronic family difficulties predicted patient satisfaction and physical disability and chronic family difficulties predicted parent satisfaction. In conclusion, most parents and patients with inflammatory rheumatic diseases were satisfied with the health care. However, some patients with idiopathic pain had unmet needs for care.  相似文献   

9.
10.
Monocytic cell lines (HL-60 and THP-1) were infected with viable Mycobacterium leprae. Levels of human hsp60 were estimated by Western blot (immunoblot) assay and a sandwich enzyme-linked immunosorbent assay. The results showed that infection of both of the cell lines induced the synthesis of human hsp60, which may be of significance in relation to autoimmune manifestations associated with mycobacterial infections.  相似文献   

11.
The role of the cumulus cells in initiating the resumption of meiosis after exposure to forskolin and dbcAMP was studied in the mouse. The resumption of meiosis was monitored by the percentage of germinal vesicle breakdown (GVBD) and polar body formation (PB). The cumulus-enclosed oocytes (CEO) and denuded oocytes (DO) were cultured with and without hypoxanthine (HX) in the culture medium. Three types of experiments were performed: (1) Effect of forskolin on spontaneous resumption of meiosis, i.e. cultures without HX, and two experiments in which HX is present throughout the culture: (2) Effect of transient exposure to forskolin or dibutyric-cyclic adenosinemonophosphate (dbcAMP) on GVBD prior to continued culture without forskolin or dbcAMP (oocyte priming). (3) Priming of CEO with forskolin for 2 hr, separation of cumulus cells and oocytes, followed by coculture of rejoined cumulus cells and oocytes, or coculture of the cumulus cells and new, unprimed DO. (1) Forskolin inhibited a spontaneous resumption of meiosis in a dose-dependent manner during the first 5 hr of culturing. After 22 hr all controls and CEO resumed meiosis, whereas only half of the DO did. (2) At least 1 hr of priming the CEO with forskolin is needed to induce GVBD and PB formation, but forskolin inhibited the resumption of meiosis when present for 24 hr. Similar results were obtained with a high concentration of dbcAMP. (3) A separation and rejoining of oocytes and cumulus cells after priming induced the resumption of meiosis in a significantly greater number of oocytes than in the control oocytes which were not primed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

12.
Clot removal at early surgery has been reported to be clinically effective for the prevention of cerebral vasospasm following subarachnoid hemorrhage (SAH) due to rupture of an intracranial aneurysm. We examined the most efficacious timing of mechanical clot removal on pharmacological responses in a monkey SAH model. Cynomolgus monkeys (Macaca fascicularis) were randomized into five groups: sham-operated, clot removal in which the clot was removed 48, 72, or 96 h after SAH, and clot groups. An autologous blood clot was placed around the bilateral major cerebral arteries after craniectomy to mimic the hemorrhage. Seven days after the SAH, proximal and successively distal parts of the middle cerebral arteries were cut into rings for isometric tension measurement. The contractile responses to potassium chloride, 5-hydroxytryptamine, norepinephrine, adenosine triphosphate, prostaglandin F20, and hemoglobin were greater in the proximal parts than in the distal parts in each group. Compared with the sham-operated group, the responses of the clot-removal and clot groups to the drugs were progressively attenuated. The maximum responses to 5-hydroxytryptamine in the proximal parts and to adenosine triphosphate in the distal parts started to decrease, significantly, in the clot-removal group 48 h after SAH, while most of the responses to the other agonists began to decrease in the clot-removal groups later than 72 h after SAH. These results suggest that the attenuation of cerebrovascular contractile responses 7 days after SAH is pharmacologically inevitable, even if the clot is removed as early as 48 h after the SAH. Clot removal may thus be recommended within 48h after SAH to ameliorate the severity of cerebral vasospasm following SAH.  相似文献   

13.
Heat shock protein Mr 27,000 (hsp27) is found in many human breast cancer cells and tissues; its expression is associated with the presence of estrogen receptors, lower cell proliferation, and resistance to certain chemotherapies. The purpose of this study was to assess whether hsp27 may be present in sera from women with primary breast cancer and to know whether autoantibodies to hsp27 may be found in these patients. The study was performed by Western blot analyzing sera from 42 normal premenopausal women, 20 normal postmenopausal women, and 36 breast cancer patients. hsp27 was clearly detected in sera by immunoblotting but only after immunoprecipitation. The mean hsp27 levels in cancer patients were higher than in the control patients; however, 66% of the breast cancer patients showed hsp27 within the normal range, indicating low sensitivity. Moreover, cancer patients with metastatic disease did not show significantly higher hsp27 levels than cancer patients without metastases. Serum hsp27 levels did not correlate with the hsp27 levels in tumor tissues detected by immunohistochemistry. Elevated CA 15-3 levels were not associated with high hsp27 values. Autoantibodies against hsp27 were not detected by immunoblotting in normal sera and in sera from breast cancer patients. As a consequence, serological determination of this biomarker is unlikely to be of utility in the detection and follow-up of breast cancer patients.  相似文献   

14.
BACKGROUND: Reading acuity as well as reading speed are good predictors of everyday visual function. As visual acuity tests are poor predictors of the real-world function, performance-based tests, e.g., reading speed measurements, can be used for the determination of visual function. Thus, a German reading chart was developed in order to evaluate reading acuity as well as reading speed. METHODS: Print size is defined as the height of a lower case x and progresses logarithmically from one phrase to another (factor: 1.25). Reading acuity is determined in LogRAD (Reading Acuity Determination). 32 short German phrases were created, comparable concerning grammatical difficulty as well as in number (n = 14), length and position of words. The reading speed parameters measured with a stop-watch in 160 persons (aged: Phi = 21a +/- 3.8a) were calculated in words per minute (w/min). Out of the 32 phrases the 24 most similar ones were selected statistically and used for the reading charts (Radner Reading Charts). With these reading charts a reading acuity score (LogRAD-score) can be calculated considering reading errors in words of different length. Reading speed can be determined at the same time. Reading acuity (LogRAD-Score) was measured in 32 normal eyes of 16 students and compared to the angular visual acuity (LogMAR). RESULTS: The mean reading speed of the test persons was 211.8 +/- 34.1 w/min. 24 phrases fulfilled the test item criteria for the reading chart: mean +/- 0.25 x SD. The reliability analyses yielded an overall Cronbach's alpha coefficient of 0.98! The mean visual acuity measured in 32 eyes was -0.115 +/- 0.097 LogMAR and the mean reading acuity score was +0.026 +/- 0.091 LogRAD. The mean difference was +0.104 +/- 0.066 and the correlation between LogMAR and LogRAD was good (r = 0.59). CONCLUSIONS: With these reading charts it is for the first time possible to simultaneously determine reading acuity as well as reading speed in German. The high reliability of the 24 phrases and the high correlation between LogMAR and LogRAD leads us to expect a good reproducibility of the reading acuity evaluations. For the "Radner Reading Charts" we have shown that print size is the main reason for changes of reading speed.  相似文献   

15.
It is now well recognized that a disorder of left ventricular filling can be sufficient to account for congestive heart failure. Furthermore, evaluation of heart disease would not be complete if it did not include assessment of left ventricular filling, improvement of which probably ensures better control of the heart disease. An efficient and reliable tool for the study of diastolic function is therefore essential. The authors review the current state of knowledge and the more recent developments in Doppler echocardiography in the evaluation of left ventricular diastolic function. After revising the pathophysiology, the methods of studying ventricular filling are described. The recording technique is described, taking into account recent developments in transthoracic and transoesophageal approaches. This investigation provides parameters allowing semiquantitative estimation of filling pressures (mean left atrial pressure, end-diastolic pressure) and reliable evaluation of overall diastolic performance.  相似文献   

16.
The increasing interest in stress/heat shock proteins (Hsps) as markers of exposure to environmental stress or disease requires an easily applicable method for Hsp determination in peripheral blood cells. Of these cells, monocytes preferentially express Hsps upon stress. An appropriate fixation/permeabilization procedure was developed, combined with immunofluorescence staining and flow cytometry for the detection of the inducible, cytosolic, 72 kDa Hsp (Hsp70) in human monocytes. Higher relative fluorescence intensity was observed in cells exposed to heat shock (HS), reflecting a higher expression of Hsp70 in these cells as compared with cells kept at 37 degrees C. The heat-inducible increased Hsp70 expression was temperature- and time-dependent. Expression of Hsp70 was not uniform within the monocyte population, indicating the presence of subpopulations expressing variable levels of Hsp70 in response to HS. Simultaneous measurements of intracellular Hsp70 and membrane CD14 expression revealed that the higher Hsp70 inducibility coincided with the higher CD14 expression. Comparisons performed with biometabolic labelling, Western blotting, immunofluorescence and immunoperoxidase microscopic analysis, showed a high concordance between these different methods; however, cytometry was more sensitive for Hsp70 detection than Western blotting. Flow cytometric detection of intracellular Hsp70 is a rapid, easy and quantitative method, particularly suited for the determination of protein levels in individual cells from an heterogeneous population such as peripheral mononuclear blood cells, and applicable to cohort studies.  相似文献   

17.
Although nephrotic syndrome is a very common kidney disease, little is known about the molecular changes occurring within glomerular capillary loops during development of disease. The characteristic histologic change is retraction (effacement) of the distal "foot" processes of glomerular epithelial cells (GEC) which surround the capillary loops. The GEC foot processes are an essential part of the kidney's filtration barrier, and their structure is regulated primarily by actin microfilaments, cytoskeletal proteins present in high concentrations in foot processes. Actin polymerization has been reported to be regulated via phosphorylation of the low molecular weight heat shock protein, hsp27. We localized hsp27 within normal rat GECs using immunofluorescence and immunoelectron microscopy. Induction of nephrotic syndrome and GEC foot process effacement using the puromycin aminonucleoside rat model resulted in significant increases in: (a) renal cortical hsp27 mRNA expression (826 +/- 233%, x +/- SEM, P < 0.01 vs. control); (b) glomerular hsp27 protein expression (87 +/- 2%, P < 0.001 vs. control); and (c) glomerular hsp27 phosphorylation (101 +/- 32%, P < 0.05 vs. control). These findings support the hypothesis that hsp27, by regulating GEC foot process actin polymerization, may be important in maintaining normal foot process structure, and regulating pathophysiologic GEC cytoskeletal changes during development of nephrotic syndrome.  相似文献   

18.
High concentrations of bile acids have been reported as injurious to hepatocytes. We report the influence of various combinations of bile acids on the liver-specific function of cultured rat hepatocytes. Using 4 bile acids (glycocholate [GC], taurocholate [TC], glycohenodeoxycholate [GCDC], and taurochenodeoxycholate [TCDC]), we obtained 6 bile-acid mixtures, each containing equal amounts of 2 bile acids (total bile acids [TBA], 2 mM). Changes in gluconeogenesis, ureagenesis, DNA contents, medium alanine aminotransferase, and morphologies were compared among the paired bile acid compositions by measuring the C/CDC ratio ([GC + TC]/[GCDC + TCDC]) of each. In terms of their relative impairments of ureagenesis from greatest to least, the acids were GCDC, TCDC, and GC, which was almost the same as TC. When the C/CDC ratio was 0, the values of all parameters measured deteriorated. When the C/CDC ratio was 1 in the presence of 1 mM GCDC, only the rate of ureagenesis was diminished. When the C/CDC ratio was infinite, no hepatocellular injury was observed. GCDC and TCDC, together or separately, showed significant hepatocellular injury when the TBA concentration was 2 mM.  相似文献   

19.
The relationship of the heat shock protein HSP27 in ovarian cancer to several biological and clinical parameters was investigated in a series of primary tumors and cell lines. Analysis of 72 primary tumors (54 malignant, 5 borderline, and 13 benign neoplasms) indicated that malignant tumors expressed higher HSP27 concentrations than benign tumors (median values, 0.56 versus 0.25 ng/microgram cytosolic protein; P = 0.032). Tumors from patients with advanced stage (stages II, III, or IV) disease contained significantly higher HSP27 concentrations than tumors from stage I patients (P = 0.018), and an HSP27 content >2.0 ng/microgram cytosolic protein was associated with reduced survival (P = 0.03). Tumors that had demonstrated progressive growth after chemotherapy had a significantly higher HSP27 content than tumors that were static or responsive (P = 0.022). These data indicate that HSP27 is associated with more aggressive malignant ovarian disease and with inherent resistance to chemotherapy. Concentrations of HSP27 were also correlated with indicators of estrogen sensitivity. Therefore, the HSP27 concentration correlated with the estrogen receptor (all tumors, P = 0.0014; malignant tumors only, P = 0.047) but not with the progesterone receptor concentration. Analysis of ovarian cancer cell lines in vitro and in vivo indicated that the HSP27 content was higher in cell lines that were estrogen receptor rich and whose growth was modulated by estrogen as compared with those that were not. Additionally, two estrogen receptor-rich ovarian carcinoma lines demonstrated a small but significant decrease in HSP27 levels in response to 17beta-estradiol in culture. These results suggest that HSP27 may help identify tumors responsive to estrogens.  相似文献   

20.
Immunostaining of heat shock protein 27 (Hsp27) protein species on two-dimensional electrophoresis (2-DE) gels with enhanced sensitivity yields 59 spots reacting with anti-Hsp27 antibodies. Recombinant Hsp27 exists in 2-DE as two major protein species which comigrate in the human myocardial pattern with Hsp27 spots C754 and D899 as defined in the heart high-performance 2-DE database (http://www.mdc-berlin.de/emu/heart/). Preparative electrophoresis of human myocardial proteins and analysis of the enriched mass range 20-30 kDa by 2-DE revealed eight protein spots (C438, C582, C658, C697, C754, C595, C750) from the human myocardial database and a new spot not previously detected on silver-stained gels. These spots were identified as Hsp27 protein species by enzymatic in-gel-digestion and analysis by matrix assisted laser desorption-ionization (MALDI) peptide mass fingerprinting and, in part, MALDI-post source decay sequencing of single fragments. Possible post-translational modifications were investigated: immunostaining tests with anti-phospho-serine/-threonine/-tyrosine antibodies, although positive for other myocardial proteins, were negative for presumed Hsp27 protein species; likewise, periodate-glycostaining assays and biotinylation screening did not detect modifications in the investigated Hsp27 protein species.  相似文献   

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