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991.
Endothelial stimulation by small lymphocytic lymphoma correlates with secreted levels of basic fibroblastic growth factor 总被引:1,自引:0,他引:1
Lymph nodes (LN) involved with small lympho- cytic lymphoma (SLL) reportedly contain increased numbers of microvessels that may constitute a therapeutic target in this disease. We investigated the secretion of the angiogenic growth factor, basic fibroblastic growth factor (bFGF), from primary tissue cultures of 15 LN with SLL and 10 reactive LN. bFGF was detected from the resulting conditioned media (CM) in 13/15 SLL samples (mean 92 +/- 30, range 5-420 pg/ml) but was undetectable in CM from all reactive lymph nodes. CM was also used in a 72-h human umbilical vein endothelial cell (HUVEC) proliferation assay. HUVEC proliferation increased in the presence of SLL CM (70 +/- 17%, range -4-194%), proportional to secreted levels of bFGF (R2 = 0.95), and was reversed by depleting bFGF from CM. Previous SLL studies have examined either patient serum samples or paraffin-embedded lymph node tissue sections. This is the first study to examine the secretion of an angiogenic growth factor from primary cultures of lymph node cells. Our results indicate that bFGF is probably the primary mediator responsible for increased angiogenesis in involved nodes. These findings may be pertinent to future investigation into the mechanisms of increased angiogenesis in SLL. 相似文献
992.
Mitochondria play a key role in determining cell fate during exposure to stress. Their role during ischemia/reperfusion is particularly critical because of the conditions that promote both apoptosis by the mitochondrial pathway and necrosis by irreversible damage to mitochondria in association with mitochondrial permeability transition (MPT). MPT is caused by the opening of permeability transition pores in the inner mitochondrial membrane, leading to matrix swelling, outer membrane rupture, release of apoptotic signaling molecules such as cytochrome c from the intermembrane space, and irreversible injury to the mitochondria. During ischemia (the MPT priming phase), factors such as intracellular Ca2+ accumulation, long-chain fatty acid accumulation, and reactive oxygen species progressively increase mitochondrial susceptibility to MPT, increasing the likelihood that MPT will occur on reperfusion (the MPT trigger phase). Because functional cardiac recovery ultimately depends on mitochondrial recovery, cardioprotection by ischemic and pharmacological preconditioning must ultimately involve the prevention of MPT. Investigations into this area are beginning to unravel some of the mechanistic links between cardioprotective signaling and mitochondria. 相似文献
993.
Effects of alcoholism and gender on brain metabolism 总被引:4,自引:0,他引:4
Schweinsburg BC Alhassoon OM Taylor MJ Gonzalez R Videen JS Brown GG Patterson TL Grant I 《The American journal of psychiatry》2003,160(6):1180-1183
OBJECTIVE: Proton magnetic resonance spectroscopy was used to evaluate gender influences on alcohol-associated changes in brain metabolism. METHOD: Concentrations of N-acetylaspartate, choline-containing compounds, myo-inositol, and creatine plus phosphocreatine in frontal lobe gray matter and white matter were estimated in eight women and 17 men who were recently detoxified from long-term alcoholism. Twelve women and 13 men with no history of alcoholism were used as a comparison group. RESULTS: In male and female alcoholics, frontal lobe white matter concentrations of N-acetylaspartate were significantly lower (-8.8%) than those seen in nonalcoholic comparison subjects. In the frontal lobe gray matter region, a significant alcoholism status-by-gender interaction and follow-up analyses revealed that female alcoholics had significantly lower N-acetylaspartate concentrations (-10.73%) relative to female comparison subjects, while male alcoholics and male comparison subjects had similar levels of this metabolite (<1% difference). CONCLUSIONS: Lower concentrations of white matter N-acetylaspartate, which may indicate neuronal loss or dysfunction, is equally severe in men and women with comparable alcohol abuse histories. However, female alcoholics exhibited significantly less N-acetylaspartate in frontal gray matter relative to female nonalcoholic comparison subjects, which could mean that female alcoholics are more susceptible to gray matter injury than their male counterparts. However, this finding could also be explained by higher-than-expected levels of N-acetylaspartate in the healthy female comparison group. 相似文献
994.
Hofer A Weiss EM Golaszewski SM Siedentopf CM Brinkhoff C Kremser C Felber S Fleischhacker WW 《The American journal of psychiatry》2003,160(10):1802-1808
OBJECTIVE: Memory impairment has been well documented in schizophrenia. In a previous study, the authors investigated patterns of brain activity during episodic encoding and recognition of words in remitted, stable schizophrenia outpatients being treated with novel antipsychotics. The same procedure was used in this study to investigate unmedicated patients during an acute episode of schizophrenia. METHOD: Functional magnetic resonance imaging was used to study regional brain activation in 10 unmedicated patients experiencing an acute episode of schizophrenia and 10 healthy comparison subjects during performance of a modified version of the words subtest of Warrington's Recognition Memory Test. RESULTS: Despite intact recognition performance, patients with schizophrenia showed reduced activation of anterior prefrontal, posterior cingulate, and retrosplenial areas relative to comparison subjects during word encoding. During word recognition, reduced activation was found in the patients' dorsolateral prefrontal and limbic/paralimbic regions. On the other hand, higher metabolism in bilateral anterior prefrontal cortices was observed. CONCLUSIONS: The results suggest that different neural pathways are engaged during episodic encoding and recognition of words in patients experiencing an acute episode of schizophrenia relative to healthy comparison subjects. Furthermore, acute psychosis may prevent practice effects, reflected in a failure to engage brain regions associated with successful episodic memory retrieval in healthy subjects. 相似文献
995.
Enriched environment delays the onset of hippocampal damage after global cerebral ischemia in rats 总被引:3,自引:0,他引:3
Belayev A Saul I Liu Y Zhao W Ginsberg MD Valdes MA Busto R Belayev L 《Brain research》2003,980(1):121-127
An enriched environment has been shown to improve cognitive, behavioral and histopathological outcome after focal cerebral ischemia and head trauma. The purpose of this study was to determine the effect of an enriched environment on histopathology following global cerebral ischemia. Wistar rats (21 weeks of age) were placed in different environments [standard cages (SC) or enriched environment (EE) cages] for 2 months before and either 6 days or 2 months after ischemia. Rats underwent 10 min of global ischemia by bilateral carotid artery occlusions plus hypotension. Five groups (n=4-5 in each group) were studied: (1) rats kept in SC before and 2 months after ischemia; (2) rats kept in SC before ischemia but transferred to an EE for 2 months after ischemia; (3) rats kept in EE before and after ischemia for 2 months; (4) rats kept in SC before and 6 days after ischemia; (5) rats kept in EE before and 6 days after ischemia. At 7 days or 2 months after ischemia, brains were perfusion-fixed, and ischemic injury was assessed by counting numbers of normal neurons in the hippocampal CA1 sector. Physiological variables showed no inter-group differences. Rats housed in EE for 2 months before and for 6 days (but not 2 months) after global ischemia showed significantly better preservation of pyramidal neurons in the hippocampal CA1 area when compared to control animals (middle CA1, 20.5+/-5.4 vs. 2.8+/-0.6; lateral CA1, 31.5+/-7.2 vs. 2.6+/-0.6, respectively). The present data suggest that housing in EE for 2 months before and 6 days after ischemia can delay the onset of damage to hippocampal pyramidal neurons, which eventually occurs despite 2-month EE. 相似文献
996.
Weiss MG Saraceno B Saxena S van Ommeren M 《The Journal of nervous and mental disease》2003,191(9):611-615
997.
Functional and comparative genomic analyses of an operon involved in fructooligosaccharide utilization by Lactobacillus acidophilus 下载免费PDF全文
998.
Conditional calcineurin knockout mice exhibit multiple abnormal behaviors related to schizophrenia 总被引:13,自引:0,他引:13
Miyakawa T Leiter LM Gerber DJ Gainetdinov RR Sotnikova TD Zeng H Caron MG Tonegawa S 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(15):8987-8992
Calcineurin (CN), a calcium- and calmodulin-dependent protein phosphatase, plays a significant role in the central nervous system. Previously, we reported that forebrain-specific CN knockout mice (CN mutant mice) have impaired working memory. To further analyze the behavioral effects of CN deficiency, we subjected CN mutant mice to a comprehensive behavioral test battery. Mutant mice showed increased locomotor activity, decreased social interaction, and impairments in prepulse inhibition and latent inhibition. In addition, CN mutant mice displayed an increased response to the locomotor stimulating effects of MK-801. Collectively, the abnormalities of CN mutant mice are strikingly similar to those described for schizophrenia. We propose that alterations affecting CN signaling could comprise a contributing factor in schizophrenia pathogenesis. 相似文献
999.
Caetano R 《Alcoholism, clinical and experimental research》2003,27(8):1337-1339
This article briefly reviews the alcohol epidemiological evidence on health disparities across whites, blacks, and Hispanics. Compared with whites, Hispanic men have higher rates of alcohol-related problems, intimate partner violence, and cirrhosis mortality; black men have higher rates of intimate partner violence and cirrhosis mortality. All groups see treatment as an appropriate intervention to address alcohol problems, and there also is support for prevention. 相似文献
1000.
Caetano R Schafer J Fals-Stewart W O'Farrell T Miller B 《Alcoholism, clinical and experimental research》2003,27(2):292-300
This article represents the proceedings of a symposium at the 2002 RSA meeting in San Francisco, California. The presentations were (1) Assessing couples' agreement about alcohol involvement in intimate partner violence, by John Schafer; (2) The occurrence of partner physical aggression on days of alcohol consumption: a longitudinal diary study, by Williams Fals-Stewart; (3) The 5-year stability of intimate partner violence and drinking among White, Black, and Hispanic couples, by Raul Caetano; (4) Partner violence before and after individually-based alcoholism treatment for male alcoholic patients, by Timothy O'Farrell. The discussant was Brenda Miller. 相似文献