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91.
A program of cell death and extracellular matrix degradation is activated in the amnion before the onset of labor. 总被引:5,自引:0,他引:5 下载免费PDF全文
H Lei E E Furth R Kalluri T Chiou K I Tilly J L Tilly K B Elkon J J Jeffrey J F Strauss rd 《The Journal of clinical investigation》1996,98(9):1971-1978
Fetal membranes usually rupture during the process of labor. Premature fetal membrane rupture occurs not infrequently and is associated with significant fetal and maternal morbidity. The mechanisms of normal and pathologic fetal membrane rupture are not well understood. We have examined structural and biochemical changes in the rat amnion as labor approaches in order to characterize this process in normal pregnancy. Here we report that before the onset of active labor the amnion epithelial cells undergo apoptotic cell death which encompasses degradation of 28S ribosomal subunit RNA and associated P proteins and fragmentation of nuclear DNA. Concurrent with these cellular changes, the amnion type I collagen matrix is degraded with the accumulation of three-quarter length type I collagen fragments in extraembryonic fluid, characteristic of the cleavage of fibrillar collagen by interstitial collagenase. Western blot and immunohistochemical analyses confirmed that interstitial collagenase protein appears in association with the loss of amnion type I collagen. We conclude that amnion epithelial cells undergo a process of programmed cell death associated with orchestrated extracellular matrix degradation which begins before the onset of active labor. Thus, fetal membrane rupture is likely to be the result of biochemical changes as well as physical forces. 相似文献
92.
93.
Vascular stiffness in familial hypercholesterolaemia is associated with C-reactive protein and cholesterol burden 总被引:4,自引:0,他引:4
Cheng HM Ye ZX Chiou KR Lin SJ Charng MJ 《European journal of clinical investigation》2007,37(3):197-206
BACKGROUND: Familial hypercholesterolaemia (FH) is characterized by very high serum cholesterol and premature coronary atherosclerosis. Arterial stiffness and atherosclerosis are two major underlying pathophysiologies of arterial disease that are predictive of future cardiovascular events. The aims of this study were to quantify atherosclerosis and arterial stiffness and to evaluate their relationship with high sensitive C-reactive protein (hs-CRP) and the level of exposure to high serum cholesterol in FH patients. Materials AND METHODS: We measured traditional risk factors, hs-CRP, intima-media thickness (IMT) of carotid artery, and brachial-ankle pulse wave velocity (baPWV) in 35 heterozygous FH subjects and 17 healthy control subjects. Cholesterol-year score (CYS) was calculated to estimate the lifetime cholesterol burden in FH subjects. RESULTS: FH subjects had significantly elevated total cholesterol, low-density lipoprotein cholesterol, and carotid IMT compared with those without mutations. Among FH patients, the baPWV and carotid IMT were higher in cases with high cholesterol burden than those without. Similarly, the baPWV and carotid IMT were also higher in cases with elevated hs-CRP (> 1 mg L(-1)) than those without. Multiple linear regression analysis demonstrated CYS and hs-CRP were significant independent predictors of baPWV and IMT in FH patients. CONCLUSIONS: Both high cholesterol burden and vascular inflammation are not only associated with atherosclerosis, but also contribute to the development of arterial stiffness in FH patients. Early detection of hypercholesterolaemia in FH patients is warranted to prevent the untoward pathophysiologies. 相似文献
94.
This study was designed to pursue the identification of optimal restriction enzyme for pulsed-field gel electrophoresis (PFGE) analysis of Candida tropicalis. Twelve restriction enzymes were tested on C. tropicalis strains. Our results indicate that BssHII, NaeI, and RsrII were useful enzymes for PFGE analysis, and NaeI was the best for PFGE analysis of C. tropicalis isolates. 相似文献
95.
Gracelyn Hanley Piao‐Yi Chiou Chieh‐Yu Liu Hui‐Mei Chen Stefani Pfeiffer 《International wound journal》2020,17(5):1142-1152
About one‐third of admissions to the surgical unit annually are diabetes foot infections in need of amputation In St. Kitts and Nevis. However, the risk factors related to diabetes foot and amputation remain unknown. This study investigated factors associated with diabetic foot and amputation (DFA). Retrospective case control study design, and purposive and quota sampling method was used to recruit the participants. Patients with and without DFA were interviewed at two main hospitals, several primary health centres, and a private doctor's office during July and August 2018. Self‐development questionnaires were applied to assess patients' demographic, physical and behaviour, foot care knowledge, attitudes, and practices related to DFA. Chi‐square, t‐test, and multiple logistic regressions were used to analyse the data. A total of 210 patients were evaluated, 89 had DFA, while 121 did not, with a mean age of 61.10 (SD = 11.85). Participants' responses indicated good knowledge, favourable attitudes, and adequate practices related to foot care. The two items of the questionnaire, ways to maintain blood flow in the lower extremities and wash their feet daily, had significant lower score in DFA group. In multiple logistic regression, knowledge, attitudes, and practices related to foot care were not a significant predictor of DFA. Being male was a predictor of DFA than female (OR = 3.53; 95% CI = 1.65‐7.57; P < .01). Participants who were currently unemployed were less likely to have DFA than those who were employed (OR = 0.38; 95% Cl = 0.17‐0.86; P < .05). Comparing patients with the longest experience of diabetes mellitus (31 years or more) with those who had diabetes for the shortest period of time (between 1 and 10 years) was less likely to have DFA (OR = 0.38; 95% CI = 0.15‐0.97; P = <.05). The combination of these independent variables could explain 29% of the variance in DFA. Based on these findings, strategies to prevent diabetic foot and amputation should focus on male and outdoor heavy worker, and longer duration of diabetes patients which are identified in this study. 相似文献
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97.
AJL Jowett SWF Middleton MC Quaye H Chesterfield I Lasrado FM Witham 《Annals of the Royal College of Surgeons of England》2014,96(2):e13-e16
We present an unusual case of haematogenous osteomyelitis in the diaphysis of the tibia of an adult leading to a subacute presentation with an extracortical abscess. Fluid from the abscess grew methicillin resistant Staphylococcus aureus (MRSA) on culture; MRSA with the same antibiogram had been grown from the patient’s blood seven years earlier following a bowel resection. Drainage of the abscess and curettage of the bone lesion together with appropriate antibiotic therapy led to resolution of the osteomyelitis. 相似文献
98.
99.
Po-Hong Liu MD Yun-Hsuan Lee MD Cheng-Yuan Hsia MD Chia-Yang Hsu MD Yi-Hsiang Huang MD PhD Yi-You Chiou MD Han-Chieh Lin MD Teh-Ia Huo MD 《Annals of surgical oncology》2014,21(6):1825-1833
Background
The long-term survival in hepatocellular carcinoma (HCC) patients with portal vein tumor thrombosis (PVTT) who received surgical resection (SR) or transarterial chemoembolization (TACE) remains unclear. We compared the efficacy of SR and TACE by using a propensity score analysis.Methods
A total of 247 and 181 HCC patients with PVTT undergoing SR and TACE, respectively, were evaluated. One hundred eight pairs of matched patients were selected from each treatment arm by using a propensity score analysis.Results
Of all patients, the estimated 1-, 3-, and 5-year survival rates of patients receiving SR and TACE were 85 versus 60 %, 68 versus 42 %, and 61 versus 33 %, respectively (p < 0.001). Patients selected for SR were significantly younger and had better liver functional reserve, performance status, and smaller tumor burden. In the propensity model, the survival benefit of SR remained significant. The estimated 1-, 3-, and 5-year survival rates of patients receiving SR and TACE were 84 versus 71 %, 69 versus 50 %, and 59 versus 35 %, respectively (p = 0.004). The two groups of patients in the propensity score analysis were similar in baseline characteristics. In the Cox proportional hazards model, patients receiving TACE had a 2.044-fold increased risk of mortality compared with patients receiving SR (95 % confidence interval: 1.284–3.252, p = 0.003).Conclusions
For either unselected patients or patients in the propensity model, SR provides significantly better long-term survival than TACE. SR should be considered as a priority treatment in this subgroup of HCC patients. 相似文献100.
Ding-Hau Huang Shih-Wei Chou Yi-Lang Chen Wen-Ko Chiou 《Journal of Sports Science and Medicine》2014,13(4):921-928
The present study aimed to investigate whether facial electromyography (EMG) recordings reflect the perception of effort and primary active lower limb muscle activity during incremental workload cycling. The effects of exercise intensity on EMG activity of the corrugator supercilii (CS), masseter and vastus lateralis (VL) muscles, heart rate (HR) and the rating of perceived exertion (RPE) were investigated, and the correlations among these parameters were determined. Eighteen males and 15 females performed continuous incremental workload cycling exercise until exhaustion. CS, masseter and VL muscle activities were continuously recorded using EMG during exercise. HR was also continuously monitored during the test. During the final 30 s of each stage of cycle ergometer exercise, participants were asked to report their feeling of exertion on the adult OMNI-Cycle RPE. HR and EMG activity of the facial muscles and the primary active lower limb muscle were strongly correlated with RPE; they increased with power output. Furthermore, facial muscle activity increased significantly during high-intensity exercise. Masseter muscle activity was strongly and positively correlated with HR, RPE and VL activity. The present investigation supports the view that facial EMG activity reflects the perception of effort. The jaw clenching facial expression can be considered an important factor for improving the reporting of perceived effort during high-intensity exercise in males and females.
Key points
- Frowning and jaw clenching muscle activity reflects the perception of effort during incremental workload cycling.
- EMG activity of the masseter muscle was strongly and positively correlated with RPE, HR and lower limb EMG activity during incremental workload cycling.
- The jaw clenching facial expression can be considered an important factor for estimating the intensity of effort.