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41.
Frederica Perera Deliang Tang Robin Whyatt Sally Ann Lederman Wieslaw Jedrychowski 《Cancer epidemiology, biomarkers & prevention》2005,14(3):709-714
Polycyclic aromatic hydrocarbons (PAH), of which benzo[a]pyrene is a representative member, are combustion-related environmental pollutants and include known carcinogens. Laboratory animal studies indicate that the dose of PAHs to the fetus is on the order of a 10th that to the mother and that there is heightened susceptibility to PAH-induced carcinogenesis during the fetal and infancy periods. Carcinogen-DNA adducts, a measure of procarcinogenic genetic damage, are considered a biomarker of increased cancer risk. Here we compare the levels of benzo[a]pyrene-DNA adducts as a proxy for PAH-DNA damage measured in maternal blood and newborn cord blood obtained at delivery in four different populations of mothers (total of 867) and newborns (total of 822), representing a 30-fold range of exposure to ambient PAHs. The populations include residents in Northern Manhattan, participants in a study of the effects of the World Trade Center disaster, residents in Krakow, Poland, and residents in Tongliang, China. Mean adduct concentrations in both maternal and cord blood and the proportion of samples with detectable adducts, increased across the populations [Northern Manhattan < World Trade Center (WTC) < Krakow < Tongliang], consistent with the trend in estimated ambient exposure to PAHs (P < 0.001). For mothers, the means in the respective populations were Northern Manhattan (0.21 adducts per 10(8) nucleotides), WTC (0.23 adducts per 10(8) nucleotides), Krakow (0.28 adducts per 10(8) nucleotides), Tongliang (0.31 adducts per 10(8) nucleotides); the corresponding means in the newborns were Northern Manhattan (0.23), WTC (0.24), Krakow (0.29), Tongliang (0.31). The percentage of mothers with detectable levels of adducts in the respective populations were Northern Manhattan (36.8%), WTC (57.5%), Krakow (72.9%), Tongliang (73.4%); the corresponding percentages among the newborns were Northern Manhattan (42.4%), WTC (60.6%), Krakow (71.1%), Tongliang (79.5%). Despite the estimated 10-fold lower PAH dose to the fetus based on laboratory animal experiments, the adduct levels in the newborns were similar to or higher than in the mothers. This study suggests that the fetus may be 10-fold more susceptible to DNA damage than the mother and that in utero exposure to polycyclic aromatic hydrocarbons may disproportionately increase carcinogenic risk. The data support preventive policies to limit PAH exposure to pregnant women and children. 相似文献
43.
David G Hicks Brian J Yoder Sarah Short Shannon Tarr Nichole Prescott Joseph P Crowe Andrea E Dawson G Thomas Budd Steven Sizemore Muzaffer Cicek Toni K Choueiri Raymond R Tubbs Daniel Gaile Norma Nowak Mary Ann Accavitti-Loper Andra R Frost Danny R Welch Graham Casey 《Clinical cancer research》2006,12(22):6702-6708
PURPOSE: This study aims to determine the effect of loss of breast cancer metastasis suppressor 1 (BRMS1) protein expression on disease-free survival in breast cancer patients stratified by estrogen receptor (ER), progesterone receptor (PR), or HER2 status, and to determine whether loss of BRMS1 protein expression correlated with genomic copy number changes. EXPERIMENTAL DESIGN: A tissue microarray immunohistochemical analysis was done on tumors of 238 newly diagnosed breast cancer patients who underwent surgery at the Cleveland Clinic between January 1, 1995 and December 31, 1996, and a comparison was made with 5-year clinical follow-up data. Genomic copy number changes were determined by array-based comparative genomic hybridization in 47 breast cancer cases from this population and compared with BRMS1 staining. RESULTS: BRMS1 protein expression was lost in nearly 25% of cases. Patients with tumors that were PR negative (P=0.006) or HER2 positive (P=0.039) and <50 years old at diagnosis (P=0.02) were more likely to be BRMS1 negative. No overall correlation between BRMS1 staining and disease-free survival was observed. A significant correlation, however, was seen between loss of BRMS1 protein expression and reduced disease-free survival when stratified by either loss of ER (P=0.008) or PR (P=0.029) or HER2 overexpression (P=0.026). Overall, there was poor correlation between BRMS1 protein staining and copy number status. CONCLUSIONS: These data suggest a mechanistic relationship between BRMS1 expression, hormone receptor status, and HER2 growth factor. BRMS1 staining could potentially be used in patient stratification in conjunction with other prognostic markers. Further, mechanisms other than genomic deletion account for loss of BRMS1 gene expression in breast tumors. 相似文献
44.
William A. Corrigall Mary Ann Linseman RoseMarie D'Onofrio Hau Lei 《Psychopharmacology》1986,89(3):327-333
A previously reported paradigm in which rats run down a runway for food reward followed by morphine injection was analyzed to assess the utility of the paradigm in studies of opiate reinforcement. One experiment replicated the original report that post-trial morphine caused both an increase in runway speed and a decrease in food consumption (taste aversion) over successive trials, and showed in addition that the increase in runway speed did not occur as a result of food deprivation alone, but required the animals to have consumed food in the goal box. A second study using the quaternary opiate antagonist methyl naltrexone to block the peripheral effects of morphine suggested that the increase in runway speed has a peripheral locus while the taste aversion has a central one. A third experiment in which morphine was microinjected into either the lateral ventricle or the ventral tegmental area supported these observations, in that intracranial morphine failed to result in an increased runway speed, but did produce taste aversion after microinjection into either site. These findings also suggest that the increase in runway speed caused by post-trial morphine in this experiment has a peripheral locus of effect, which is probably distinct from the central effect that supports morphine self-administration and conditioned place preference.
Offprint requests to: W.A.CorrigallThe views expressed in this publication are those of the authors and do not necessarily reflect those of the Addiction Research Foundation 相似文献
45.
Systemic anticancer therapy for hepatocellular carcinoma (HCC) is limited by intrinsic drug resistance and accompanying liver
dysfunction. However, recent advances in molecular targeted therapy (MTT) have shed light on the treatment of advanced HCC.
A recent randomized, placebo-controlled trial demonstrated that sorafenib, a multi-target tyrosine kinase inhibitor, prolonged
overall survival and time-to-progression in patients with advanced HCC. This breakthrough highlights the potential of MTT
targeting hepatocarcinogenic pathways, such as the Raf/MAPK/ERK pathway, angiogenic pathways and the EGFR signaling pathway.
This review discusses the current status and the potential of developing novel MTTs for advanced HCC. 相似文献
46.
Contribution of Gender to Pathophysiology and Clinical Presentation of IBS: Should Management Be Different in Women? 总被引:2,自引:0,他引:2
Ann Ouyang M.B.B.S. Helena F. Wrzos M.D. Ph.D. 《The American journal of gastroenterology》2006,101(S3):S602-S609
The irritable bowel syndrome (IBS) is found more commonly in women than men. It is more prevalent in patients with chronic fatigue syndrome, fibromyalgia, and chronic pelvic pain, all syndromes characterized by pain and found predominantly in women. This article reviews evidence for a role of biological sex factors and gender on the pathways mediating visceral pain. The effect of gonadal hormones on gastrointestinal motility and the sensory afferent pathway and central processing of visceral stimuli and the contribution of gender role to the clinical presentation are discussed. Although differences in responses to treatment modalities between genders exist, the approach to IBS patients in both genders is quite similar. Nevertheless, a special attention to gender role and stress-related factors should be addressed. New developments in research, outlined in the paper, might bring more gender-specific treatments in the future. 相似文献
47.
The effect of a two day fast on maternal plasma volume and plasma protein concentration was explored in pregnant rats. Fasting between days 17 and 19 of gestation prevented the rise in plasma volume observed in ad libitum fed rats. Plasma protein concentration declined between day 17 and day 19 in both fasted and not fasted rats. Placental weight was not reduced by fasting during this stage of gestation. Fetal weight in the fasted group was 91% of the fetal weight of the ad libitum fed group. These results show that acute undernutrition, like longer term food or protein restriction, can prevent adequate plasma volume expansion and slow fetal growth. 相似文献
48.
49.
Belinda Joy Deal Rebecca A Fountain Carol Ann Russell-Broaddus Melinda Stanley-Hermanns 《Disaster Management & Response》2006,4(4):100-105
Hurricanes Katrina and Rita forced many individuals along the coast of Texas and Louisiana to seek shelter inland. Among the evacuees were residents with special needs and residents of nursing homes and group homes caring for mentally retarded and physically disabled persons. Many nurses volunteered to provide health care for those in need. This article discusses challenges and opportunities that were encountered by nurses volunteering in special-needs shelters. Issues related to human and physical resources, patient care, and confidentiality are discussed including lessons learned. As nurses who cared for evacuees in the shelter, it is hoped some of the lessons learned can be utilized in future disasters. 相似文献
50.
Invasion of oral epithelial cells by pathogenic oral bacteria may represent an important virulence factor in the progression of periodontal disease. Here we report that a clinical isolate of Prevotella intermedia, strain 17, was found to invade a human oral epithelial cell line (KB), whereas P. intermedia 27, another clinical isolate, and P. intermedia 25611, the type strain, were not found to invade the cell line. Invasion was quantified by the recovery of viable bacteria following a standard antibiotic protection assay and observed by electron microscopy. Cytochalasin D, cycloheximide, monodansylcadaverine, and low temperature (4°C) inhibited the internalization of P. intermedia 17. Antibodies raised against P. intermedia type C fimbriae and against whole cells inhibited invasion, but the anti-type-C-fimbria antibody inhibited invasion to a greater extent than the anti-whole-cell antibody. This work provides evidence that at least one strain of P. intermedia can invade an oral epithelial cell line and that the type C fimbriae and a cytoskeletal rearrangement are required for this invasion. 相似文献