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61.
Inhibition of growth and induction of apoptosis in human cancer cell lines by tea polyphenols 总被引:47,自引:7,他引:47
In order to study the biological activities of tea preparations and
purified tea polyphenols, their growth inhibitory effects were investigated
using four human cancer cell lines. Growth inhibition was measured by
[3H]thymidine incorporation after 48 h of treatment. The green tea
catechins (-)-epigallocatechin-3-gallate (EGCG) and (-)- epigallocatechin
(EGC) displayed strong growth inhibitory effects against lung tumor cell
lines H661 and H1299, with estimated IC50 values of 22 microM, but were
less effective against lung cancer cell line H441 and colon cancer cell
line HT-29 with IC50 values 2- to 3- fold higher.
(-)-Epicatechin-3-gallate, had lower activities, and (-)- epicatechin was
even less effective. Preparations of green tea polyphenols and theaflavins
had higher activities than extracts of green tea and decaffeinated green
tea. The results suggest that the growth inhibitory activity of tea
extracts is caused by the activities of different tea polyphenols. Exposure
of H661 cells to 30 microM EGCG, EGC or theaflavins for 24 h led to the
induction of apoptosis as determined by an annexin V apoptosis assay,
showing apoptosis indices of 23, 26 and 8%, respectively; with 100 microM
of these compounds, the apoptosis indices were 82, 76 and 78%,
respectively. Incubation of H661 cells with EGCG also induced a
dose-dependent formation of H2O2. Addition of H2O2 to H661 cells caused
apoptosis in a manner similar to that caused by EGCG. The EGCG-induced
apoptosis in H661 cells was completely inhibited by exogenously added
catalase (50 units/ml). These results suggest that tea polyphenol-induced
production of H2O2 may mediate apoptosis and that this may contribute to
the growth inhibitory activities of tea polyphenols in vitro.
相似文献
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Leon Eisenberg MD 《Medicine, conflict, and survival》2013,29(4):243-250
Rudolf Virchow's life is an eloquent instance of the way professional and political activities can and should be integrated, if physicians are to live up to the highest ideals of the profession. At one and the same time father of pathology and father of social medicine, Virchow carried the results of his research to the public arena by advocating such measures as medical care for the poor, compulsory meat inspection to eliminate trichinosis, and the improvement of public sanitation. Elected to public office, Virchow led the protest against Bismarck's militarism despite the personal risk involved. His disarmament resolution, had it been accepted, might have averted the tragic Franco‐Prussian War of 1870. Few of us can match his scientific accomplishments. Every physician can be inspired by his personal courage and his commitment to humane values. No task can be higher on the agenda of medicine than the defence of peace, the precondition for health in the nuclear era. 相似文献
64.
Sara G. Cifuentes James Trostle Gabriel Trueba Meghan Milbrath Manuel E. Baldeón Josefina Coloma Joseph N.S. Eisenberg 《Emerging infectious diseases》2013,19(10):1642-1645
In tropical areas, the predominant cause of fever has historically been malaria. However by 2011, among febrile patients in northwestern Ecuador, dengue was identified in 42% and malaria in none. This finding suggests a transition in the cause of fever from malaria to other illnesses, such as dengue. 相似文献
65.
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The heightened risk of persons with serious mental illness (SMI) to contract and transmit human immunodeficiency virus (HIV) is a public health problem. Our objective was test the effectiveness of a community-based advanced practice nurse intervention to promote adherence to HIV and psychiatric treatment regimens call Preventing AIDS Through Health for Positives (PATH+). We enrolled 238 HIV-positive subjects with SMI who were in treatment at community HIV provider agencies from 2004 to 2009. Participants in the intervention group were assigned an advanced practice nurse who provided community-based care management at a minimum of one visit/week and coordinated their medical and mental healthcare for 12 months. A parallel process latent growth curve model using three data points for biomarkers (baseline, 12 and 24 months) and five data points for health related quality of life (baseline, 3, 6, 12, and 24 months) showed moderate to excellent fit for modeling changes in CD4, viral load, and mental and physical SF-12 subscales. Results suggest that positive effects for PATH+ persisted at 24 months; 12 months after the intervention ended. This project demonstrates the effectiveness of a nurse-led, community-based, individually tailored adherence intervention. We demonstrated improved outcomes in individuals with HIV/SMI and regarding health-related quality of life and reductions in disease burden. 相似文献
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Michael J. Mitchell Benjamin A. Stubbs Mickey S. Eisenberg 《Prehospital emergency care》2013,17(4):478-486
Objective. Although socioeconomic status (SES) has been linked to multiple health outcomes, there have been few studies of the effect of SES on the provision of bystander cardiopulmonary resuscitation (CPR) during cardiac arrest events and no studies that we know of on the effect of SES on the provision of dispatcher-assisted bystander CPR. This study sought to define the relationship between SES and the provision of bystander CPR in an emergency medical system that includes dispatcher-provided CPR instructions. Methods. This study was a retrospective, cohort analysis of cardiac arrests due to cardiac causes occurring in private residences in King County, Washington, from January 1, 1999, to December 31, 2005. We used the tax-assessed value of the location of the cardiac arrest as an estimate of the SES of potential bystanders as well as multiple measures from 2000 Census data (education, employment, median household income, and race/ethnicity). We also examined the effect of patient and system characteristics that may affect the provision of bystander CPR. Logistic regression models were used to analyze the association of these factors with two outcomes: the provision of bystander CPR with and without dispatcher assistance. Results. Forty-four percent (1,151/2,618) of cardiac arrest victims received bystander CPR. Four hundred fifty-seven people (17.5% of the entire study population, 39.7% of those who received any bystander CPR) received CPR without telephone instructions. A total of 694 people received dispatcher-assisted bystander CPR (25.6% of the entire population, 60.4% of those receiving any bystander CPR). After adjusting for demographic and care factors, we found a strong association between the tax-assessed value of the cardiac arrest location and increased odds of the provision of bystander CPR without dispatcher instructions and bystander CPR with dispatcher assistance compared with no bystander CPR. Conclusions. This study suggests that higher bystander SES is associated with increased rates of bystander CPR with and without dispatcher instructions. CPR training programs that target lower-SES communities and assessment of these training methods may be warranted. 相似文献
70.