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91.
Expression of collagen, interstitial collagenase, and tissue inhibitor of metalloproteinases-1 in restenosis after carotid endarterectomy. 总被引:3,自引:2,他引:3
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![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
S. T. Nikkari R. L. Geary T. Hatsukami M. Ferguson R. Forough C. E. Alpers A. W. Clowes 《The American journal of pathology》1996,148(3):777-783
Extracellular matrix is the principal component of the fibrous caps of atherosclerotic plaques and intimal hyperplastic lesions of reconstructed arteries. Interstitial collagen form an important part of the matrix, and the balance between collagen synthesis and degradation by interstitial collagenase (matrix metalloproteinase-1, MMP-1) may determine whether plaques rupture or vessels develop stenosis. We examined type I procollagen gene expression in human atherosclerotic and restenotic carotid arteries using in situ messenger RNA (mRNA) hybridization and the expression of MMP-1 and its endogenous inhibitor (tissue inhibitor of metalloproteinases-1, TIMP-1) by immunohistochemistry. Compared with normal arteries, atherosclerotic plaques bed increased expression of immunoreactive MMP-1 and TIMP-1 with modest increase of type 1 procollagen mRNA. Early restenotic lesions (< 1.5 years) contained abundant type I procollagen mRNA but little immunoreactive MMP-1 and TIMP-1. Late restenotic lesions (> 4 years) resembled atheroma and exhibited increased immunoreactive MMP-1 and TIMP-1 as well as abundant type I procollagen mRNA. Compared with atherosclerotic plaques, type I procollagen is increased and MMP-1 is decreased in early restenotic lesions. MMP-1 and TIMP-1 expressions are upregulated in lesions with a clear atheroma. These findings suggest that the balance between proteolysis and matrix synthesis may influence both the stability of atheromatous plaques and the development of restenotic lesions. 相似文献
92.
Previously, we demonstrated that positively charged polylysine, our model for biological polyamines, activates the Mg2+ ATPase activity of unphosphorylated smooth muscle myosin and shifts the myosin conformation from the folded 10S to linear 6S form. These effects of polylysine were reversed by the oppositely charged heparin (Szymanski et al. (1993) Am J Physiol 265, C379). In the present report, we provide further information on polylysine binding to smooth muscle myosin, and test the hypothesis that polylysine binding to unphosphorylated myosin involves filament formation. To relate the effects of polylysine on contractility in smooth muscle to physiologically relevant material, we investigated the ability of naturally occurring positively charged polyamines, histones, cadaverine, putrescine and spermidine to activate the Mg2+ ATPase activity of unphosphorylated smooth muscle myosin. Our data show that polylysine binding to individual unphosphorylated myosin molecules stimulates formation of myosin filaments. Polylysine also interacts with myosin filaments, causing enhancement of their size and the numbers, and this could be reversed by heparin. Polylysine binding to myosin filaments made them more resistant to disassembly by high salt concentrations (KCl) or ATP. Naturally occurring polyamines in millimolar concentrations activate the Mg2+ ATPase activity of unphosphorylated smooth muscle myosin. We suggest that the electrostatic interactions between naturally occurring positively charged polyamines and unphosphorylated smooth muscle myosin may play a role in stabilization of thick filament structurein situ. 相似文献
93.
The incidence of thyroglobulin antibodies and thyroid enlargement in a general practice in north-east England 总被引:3,自引:2,他引:3
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![点击此处可从《Clinical and experimental immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
P. R. Dingle A. Ferguson D. B. Horn J. Tubmen R. Hall 《Clinical and experimental immunology》1966,1(3):277-284
Antibodies to thyroglobulin in a titre of 1:25 or more were found in 16·2% of women and 4·3% of men between the ages of 21 and 80 years in a random sample of the population from a general practice in the north-east of England. The incidence of antibodies was highest in the seventh decade in both sexes. High antibody titres (1:78125 or more) were found in 4·6% of women and 1·6% of men and it is suggested that this may represent the incidence of diffuse thyroiditis in the population.
Significant thyroid enlargement was found in 12% of women and 0·9% of men, the corrected incidence of goitre obtained by averaging the frequency of goitres in each decade between 21 and 80 years was 8·9% and 0·9% respectively.
相似文献94.
High prevalence of Helicobacter pylori in saliva demonstrated by a novel PCR assay. 总被引:12,自引:1,他引:12
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![点击此处可从《Journal of clinical pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
C Li P R Musich T Ha D A Ferguson Jr N R Patel D S Chi E Thomas 《Journal of clinical pathology》1995,48(7):662-666
AIMS--To investigate the prevalence of Helicobacter pylori in the saliva of patients infected with this bacterium. METHODS--A novel polymerase chain reaction (PCR) assay was developed to detect H pylori in saliva and gastric biopsy specimens from patients undergoing endoscopy. RESULTS--Our PCR assay amplified a 417 base pair fragment of DNA from all 21 DNAs derived from H pylori clinical isolates but did not amplify DNA from 23 non-H pylori strains. Sixty three frozen gastric biopsy and 56 saliva specimens were tested. H pylori specific DNA was detected by PCR in all 39 culture positive biopsy specimens and was also identified from another seven biopsy specimens which were negative by culture but positive by histology. H pylori specific DNA was identified by PCR in saliva specimens from 30 (75%) of 40 patients with H pylori infection demonstrated by culture or histological examination, or both, and in three patients without H pylori infection in the stomach. CONCLUSION--The results indicate that the oral cavity harbours H pylori and may be the source of infection and transmission. 相似文献
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97.
Human chorionic gonadotrophin (hCG) is a placental protein whose ectopic secretion by nontrophoblast tumors has been claimed to be of clinical relevance. Serum levels of hCG were measured in 570 patients with breast disease. A double-antibody radioimmunoassay (RIA) using antisera to hCG-beta was employed. Approximately 14% of patients with breast cancer were found to have elevated serum hCG levels. Such raised titers were not stage- or tumor-type-related, but occurred only in postmenopausal subjects. Further study showed that those patients with elevated hCG levels also had raised levels of human luteinizing hormone (hLH). Assay cross-reactivity was shown to account for the "spurious" hCG elevations. An immunocytochemical study also failed to find hCG an ectopic breast tumor constituent and/or product. It is concluded that hCG is not produced by breast tumors and has no clinical utility. 相似文献
98.
Mara L. Leimanis-Laurens Karen Ferguson Emily Wolfrum Brian Boville Dominic Sanfilippo Todd A. Lydic Jeremy W. Prokop Surender Rajasekaran 《Nutrients》2021,13(3)
Lipids are molecules involved in metabolism and inflammation. This study investigates the plasma lipidome for markers of severity and nutritional status in critically ill children. Children with multi-organ dysfunction syndrome (MODS) (n = 24) are analyzed at three time-points and cross-referenced to sedation controls (n = 4) for a total of N = 28. Eight of the patients with MODS, needed veno-arterial extracorporeal membrane oxygenation (VA ECMO) support to survive. Blood plasma lipid profiles are quantified by nano-electrospray (nESI), direct infusion high resolution/accurate mass spectrometry (MS), and tandem mass spectrometry (MS/MS), and compared to nutritional profiles and pediatric logistic organ dysfunction (PELOD) scores. Our results show that PELOD scores were not significantly different between MODS and ECMO cases across time-points (p = 0.66). Lipid profiling provides stratification between sedation controls and all MODS patients for total lysophosphatidylserine (lysoPS) (p-value = 0.004), total phosphatidylserine (PS) (p-value = 0.015), and total ether-linked phosphatidylethanolamine (ether-PE) (p-value = 0.03) after adjusting for sex and age. Nutrition intake over time did not correlate with changes in lipid profiles, as measured by caloric and protein intake. Lipid measurement in the intensive care environment shows dynamic changes over an 8-day pediatric intensive care unit (PICU) course, suggesting novel metabolic indicators for defining critically ill children. 相似文献
99.
100.
Siobhan C. McKay Hanns Lembach Angus Hann Kelvin Okoth Joy Anderton Krishnarajah Nirantharakumar Laura Magill Barbara Torlinska Matthew Armstrong Jorge Mascaro Nicholas Inston Thomas Pinkney Aaron Ranasinghe Richard Borrows James Ferguson John Isaac Melanie Calvert M. Thamara P. R. Perera Hermien Hartog 《Transplant international》2021,34(11):2122-2137
Strict isolation of vulnerable individuals has been a strategy implemented by authorities to protect people from COVID-19. Our objective was to investigate health-related quality of life (HRQoL), uncertainty and coping behaviours in solid organ transplant (SOT) recipients during the COVID-19 pandemic. A cross-sectional survey of adult SOT recipients undergoing follow-up at our institution was performed. Perceived health status, uncertainty and coping strategies were assessed using the EQ-5D-5L, Short-form Mishel Uncertainty in Illness Scale (SF-MUIS) and Brief Cope, respectively. Interactions with COVID-19 risk perception, access to health care, demographic and clinical variables were assessed. The survey was completed by 826 of 3839 (21.5%) invited participants. Overall, low levels of uncertainty in illness were reported, and acceptance was the major coping strategy (92%). Coping by acceptance, feeling protected, self-perceived susceptibility to COVID-19 were associated with lower levels of uncertainty. Health status index scores were significantly lower for those with mental health illness, compromised access to health care, a perceived high risk of severe COVID-19 infection and higher levels of uncertainty. A history of mental health illness, risk perceptions, restricted healthcare access, uncertainty and coping strategies was associated with poorer HRQoL in SOT recipients during strict isolation. These findings may allow identification of strategies to improve HRQoL in SOT recipients during the pandemic. 相似文献