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31.
Amy C Y Lo Alvin K H Cheung Victor K L Hung Chung-Man Yeung Qing-Yu He Jen-Fu Chiu Stephen S M Chung Sookja K Chung 《Journal of cerebral blood flow and metabolism》2007,27(8):1496-1509
Previously, we reported that transgenic mice overexpressing endothelin-1 in astrocytes showed more severe neurological deficits and increased infarct after transient focal ischemia. In those studies, we also observed increased level of aldose reductase (AR), the first and rate-limiting enzyme of the polyol pathway, which has been implicated in osmotic and oxidative stress. To further understand the involvement of the polyol pathway, the mice with deletion of enzymes in the polyol pathway, AR, and sorbitol dehydrogenase (SD), which is the second enzyme in this pathway, were challenged with similar cerebral ischemic injury. Deletion of AR-protected animals from severe neurological deficits and large infarct, whereas similar protection was not observed in mice with SD deficiency. Most interestingly, AR(-/-) brains showed lowered expression of transferrin and transferrin receptor with less iron deposition and nitrotyrosine accumulation. The protection against oxidative stress in AR(-/-) brain was also associated with less poly(adenosine diphosphate-ribose) polymerase (PARP) and caspase-3 activation. Pharmacological inhibition of AR by Fidarestat also protected animals against cerebral ischemic injury. These findings are the first to show that AR contributes to iron- and transferrin-related oxidative stress associated with cerebral ischemic injury, suggesting that inhibition of AR but not SD may have therapeutic potential against cerebral ischemic injury. 相似文献
32.
Kuo-Sheng Hung MD Phd Chung-Ling Liang MD Cheng-Haung Wang MD Hsueh-Wen Chang PhD Naeun Park MS Suh-Hang Hank Juo MD PhD 《Journal of clinical neuroscience》2004,11(8):849-853
Frontal intracerebral haemorrhage (ICH) is a common result of cranial trauma. Outcome differences between bilateral and unilateral frontal ICH are not well studied but would be valuable to predict prognosis in clinical practice. Two aims are proposed in this study: first to compare the risk of developing delayed ICH after bilateral or unilateral frontal ICH, and second to determine the variables helpful to predict outcome according to the Glasgow Outcome Scale (GOS). Between January 1993 and December 1997, 694 consecutive patients with traumatic ICH were admitted to the Chang Gung Medical Center within 24 h of the trauma. Patients with ICH in sites other than the frontal lobes were excluded. A total of 161 cases (mean age 46.3+/-20.3 years), including 57 bilateral (mean age 52.5+/-18.7 years) and 104 unilateral (mean age 42.9+/-20.5 years) traumatic frontal ICH were studied. Twenty-eight of 57 patients (49%) with bifrontal ICH versus 17 of 104 patients (16%) with unilateral frontal ICH had a further, delayed ICH. In 42 of 45 patients (93%) with delayed ICH, this occurred within 5 days of the initial trauma. Multivariate logistic regression was used to select significant predictors of outcome. We found that delayed ICH (p<0.001), age (p=0.004) and mechanism of injury (p=0.001) explained the worse outcome in patients with bifrontal ICH. The best-fitting logistic regression model included three variables: delayed ICH (p=0.011), initial GCS (p=0.023), and a sum score of clinical and radiological variables (p=0.003). Bifrontal ICH tended to occur in older patients after a fall and was associated with a higher risk of developing delayed ICH or brain stem compression compared to unilateral ICH damage. Using these three variables - delayed ICH, initial GCS, and the sum score - in a logistical regression model is useful to predict outcome in patients with traumatic frontal ICH and may aid patient management. 相似文献
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BACKGROUND AND PURPOSE: There are limited data on the pattern of cancer distribution among adolescents in Taiwan. This study evaluated the characteristics of these rare cancers in a medical center. METHODS: Analyses of the characteristics of malignant neoplasms for patients aged 14 to 17 years at diagnosis were performed for all cases recorded in the tumor registry of Chang Gung Memorial Hospital (CGMH) at Linkou for the period 1995 to 2001. All eligible tumors were categorized in 1 of 12 diagnostic groups according to the scheme of the International Classification of Childhood Cancer (ICCC). Relative frequencies, age, and gender variations and the characteristics of tumor types were analyzed. RESULTS: Cancer was diagnosed in 320 adolescents during the study period. The male/female ratio was 1.17. Leukemia was the leading diagnostic group. The frequency of carcinomas increased with age and was highest among 17-year-olds. In this age group, non-rhabdomyosarcoma soft tissue sarcoma/primitive neuroectodermal tumor (non-RMS STS/PNET), thyroid carcinoma (CA) and ovarian germ cell tumor (GCT) were the 3 most common solid tumors; the embryonal malignancies were rare. Tumors with the greatest male predominance were intracranial GCT (91%), nasopharyngeal CA (87.5%), osteosarcoma (84.6%), and colorectal CA (75%). Tumors with the greatest female predominance were thyroid CA (78.3%), gonadal GCT (75%), and non-RMS/PNET (56.5%). Hepatocellular CA comprised 9.4% of all carcinomas. CONCLUSIONS: The relative frequency and the distribution of histology subtypes among adolescents were between those of childhood and adult cancers. There were marked variations in tumor occurrence between genders and among different ages. 相似文献
36.
Synergistic effects of Nell-1 and BMP-2 on the osteogenic differentiation of myoblasts. 总被引:1,自引:0,他引:1
Catherine M Cowan Xinquan Jiang Tiffany Hsu Chia Soo Beiji Zhang Joyce Z Wang Shun'ichi Kuroda Benjamin Wu Zhiyuan Zhang Xinli Zhang Kang Ting 《Journal of bone and mineral research》2007,22(6):918-930
Osteogenesis is synergistically enhanced by the combined effect of complimentary factors. This study showed that Nell-1 and BMP-2 synergistically enhanced osteogenic differentiation of myoblasts and phosphorylated the JNK MAPK pathway. The findings are important because of the osteochondral specificity of Nell-1 signaling and the potential therapeutic effects of coordinated BMP-2 and Nell-1 delivery. INTRODUCTION: BMPs play an important role in the migration and proliferation of mesenchymal cells and have a unique ability to alter the differentiation of mesenchymal cells toward chondrogenic and osteogenic lineages. Signaling upstream of Cbfa1/Runx2, BMPs effects are not limited to cells of the osteoblast lineage. Thus, additional osteoblast-specific factors that could synergize with BMP-2 would be advantageous for bone regeneration procedures. NELL-1 (NEL-like molecule-1; NEL [a protein strongly expressed in neural tissue encoding epidermal growth factor like domain]) is a novel growth factor believed to preferentially target cells committed to the osteochondral lineage. MATERIALS AND METHODS: C2C12 myoblasts were transduced with AdLacZ, AdNell-1, AdBMP-2, or AdNell-1+AdBMP-2 overexpression viruses. Effects were studied by cell morphology, alkaline phosphatase activity, osteopontin production, and MAPK signaling. Additionally, in a nude mouse model, viruses were injected into leg muscles, and new bone formation was examined after 2 and 8 wk. RESULTS: C2C12 myoblasts co-transduced with AdNell-1+AdBMP-2 showed a synergistic effect on osteogenic differentiation as detected by alkaline phosphatase activity and osteopontin production. Nell-1 stimulation on AdNell-1 + AdBMP-2 preconditioned C2C12 cells revealed significant activation of the non-BMP-2 associated c-Jun N-terminal kinase (JNK) MAPK signaling pathway, but not the p38 or extracellular signal-regulated kinase (ERK1/2) MAPK pathways. Importantly Nell-1 alone did not induce osteogenic differentiation of myoblasts. In a nude mouse model, injection of AdNell-1 alone stimulated no bone formation within muscle; however, injection of AdNell-1+AdBMP-2 stimulated a synergistic increase in bone formation compared with AdBMP-2 alone. CONCLUSIONS: These findings are important because of the confirmed osteochondral specificity of Nell-1 signaling and the potential therapeutic effects of enhanced BMP-2 action with coordinated Nell-1 delivery. 相似文献
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Can Electrocardiographic Criteria Predict Adverse Cardiac Events and Positive Cardiac Markers? 总被引:5,自引:0,他引:5
Andra L. Blomkalns MD Christopher J. Lindsell PhD Abhinav Chandra MD Mary E. Osterlund MD W. Brian Gibler MD Charles V. Pollack MS MD Brian R. Tiffany MD PhD Judd E. Hollander MD James W. Hoekstra MD 《Academic emergency medicine》2003,10(3):205-210
OBJECTIVES: To determine electrocardiogram (ECG) predictors of positive cardiac markers and short-term adverse cardiac events in an undifferentiated chest pain population presenting to emergency departments (EDs). The authors hypothesized that specific ECG findings, other than those previously identified in higher-risk populations, would be predictive of cardiac outcomes and positive cardiac markers. METHODS: This study used data from a prospectively collected, retrospectively analyzed Internet-based data registry of undifferentiated chest pain patients (i*trACS). Logistic regression modeling was performed to determine the ECG findings that were predictive of 1) positive cardiac markers and 2) short-term adverse cardiac events. RESULTS: ST-segment elevation (STE), ST-segment depression (STD), pathological Q-waves (PQW), and T-wave inversion were associated with increased odds of percutaneous coronary intervention or catheterization, myocardial infarction, or coronary artery bypass grafting. The odds of creatine kinase-MB (CK-MB) measuring positive were increased if STE, STD, or PQW were present [odds ratio (OR) 2.495, 2.582, and 1.295, respectively]. A right bundle branch block tended to decrease the odds of CK-MB measuring positive (OR 0.658). A similar pattern of results was observed for troponin I (OR 3.608 for STE, 3.72 for STD, 1.538 for PQW). Troponin T showed an increased odds of measuring positive if any of STE, STD, left bundle branch block, or T-wave inversion were evident (OR 2.313, 2.816, 1.80, and 1.449, respectively). CONCLUSIONS: Initial ECG criteria can be used to predict short-term cardiac outcomes and positive cardiac markers. These findings can be important aids in the risk-stratification and aggressive treatment regimens of chest pain patients presenting to EDs. 相似文献
39.
Urethral reconstruction with graft substances, such as skin and bladder mucosa, has been previously used when primary anastomosis cannot be achieved. However, stricture and meatal prolapse are associated with these grafts. We report the use of buccal mucosa for the reconstruction of urethral defects in 3 patients. One patient with failed operation for hypospadias received tube buccal mucosal graft for urethral replacement. Two patients with urethral necrosis and stricture received onlay buccal mucosal graft. All patients were disease-free during follow-up (range, 12 to 49 months; mean, 36 months). One patient had a pinhole fistula that was successfully managed with simple repair. This technique appears to be useful for urethral reconstruction when a local graft is not available, even in patients with complicated conditions. 相似文献
40.
Tiffany M. Field Saul Schanberg Marisabel Davalos Julie Malphurs 《Early child development and care》1997,132(1):57-65
Forty normal one-month-old infants were randomly assigned to a breast-like nipple (Healthflow) bottlefeeding or a standard nipple (Evenflo) bottlefeeding group for one 20-minute feeding by the infants' mothers. The data suggested that the mothers' bottlefeeding behaviors did not differ, but the infants who fed on the breast-like nipples spent less time asleep, more time awake and active and less time fussing and crying. In addition, the vagal tone of that group decreased more during bottlefeeding and increased more after the feeding, suggesting that the breast-like nipple bottlefeedings were more similar to breastfeedings (vagal tone being lower during breastfeeding and higher after breastfeeding versus bottlefeeding). Because many women who breastfeed return to work, bottlefeeding that more closely approximate breastfeedings may ease this transition and may provide more effective supplemental feedings for the breastfed infants. 相似文献