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41.
Inbal Weiss-Salz Susan Harlap Yehiel Friedlander Luna Kaduri Efrat Levy-Lahad Rivka Yanetz Lisa Deutsch Hagit Hochner Ora Paltiel 《European journal of cancer prevention》2007,16(6):549-554
To study the risk factors associated with breast cancer in women younger than 40 years, a cohort study (The Jerusalem Perinatal Study) of 42 822 female offspring born in hospitals in West Jerusalem during 1964-1976 was carried out. Hazard ratios of potential parental and perinatal risk factors for early breast cancer were measured. The overall incidence of breast cancer was 5.2/100 000 person-years. The highest incidence was found among Jewish women of West Asian ancestry (8.6/100 000 person-years), specifically those whose maternal grandfathers were born in Iraq, Iran or Afghanistan (9.5/100 000 person-years). Using Cox models we found independent risk factors for early breast cancer to be paternal age (relative risk/year=1.06, 95% confidence interval=1.02-1.10, P=0.005), and ancestry from Iraq/Iran/Afghanistan (relative risk=3.1, 95% confidence interval=1.50-6.52, P=0.002). The study confirms a previously observed effect of advanced paternal age on the occurrence of early breast cancer and identifies a novel population group at increased risk for the disease. The excess risk of early breast cancer associated with ancestry from Iraq, Iran and Afghanistan suggests involvement of genetic determinants, environmental exposures and/or lifestyle factors and mandates further investigation. 相似文献
42.
Zohar Tiran Anat Oren Chen Hermesh Galit Rotman Zurit Levine Hagit Amitai Tal Handelsman Merav Beiman Aviva Chen Dalit Landesman-Milo Liat Dassa Yair Peres Cynthia Koifman Sarit Glezer Rinat Vidal-Finkelstein Kobi Bahat Tania Pergam Cylia Israel Judith Horev Ilan Tsarfaty Michal Ayalon-Soffer 《Clinical cancer research》2008,14(14):4612-4621
PURPOSE: The Met receptor tyrosine kinase and its ligand, hepatocyte growth factor/scatter factor (HGF/SF), are involved in a wide range of biological activities, including cell proliferation, motility, invasion, and angiogenesis. The HGF/SF-Met signaling pathway is frequently activated in a variety of cancers, and uncontrolled Met activation correlates with highly invasive tumors and poor prognosis. In this study, we investigated the inhibitory effect of a novel soluble splice variant of Met on the HGF/SF-Met pathway. EXPERIMENTAL DESIGN: Using our alternative splicing modeling platform LEADS, we have identified a novel splice variant of the Met receptor, which encodes a truncated soluble form of the receptor. This variant was produced as a recombinant Fc-fused protein named Cgen-241A and was tested in various cell-based assays representing different outcomes of the HGF/SF-Met pathway. RESULTS: Cgen-241A significantly inhibited HGF/SF-induced Met phosphorylation as well as cell proliferation and survival. In addition, Cgen-241A showed a profound inhibitory effect on cell scattering, invasion, and urokinase up-regulation. The inhibitory effects of Cgen-241A were shown in multiple human and nonhuman cell types, representing different modes of Met activation. Furthermore, Cgen-241A showed direct binding to HGF/SF. CONCLUSIONS: Taken together, our results indicate that Cgen-241A is a potent antagonist of the HGF/SF-Met pathway, underlining its potential as a therapeutic agent for the treatment of a wide variety of human malignancies that are dependent on this pathway. 相似文献
43.
Powers JF Schelling K Brachold JM Tsokas P Schayek H Friedman E Tischler AS 《Molecular and cellular neurosciences》2002,20(3):382-389
Pheochromocytoma cell lines derived from neurofibromatosis knockout mice express high levels of the receptor tyrosine kinase Ret, which is involved in the pathogenesis of human pheochromocytomas in hereditary multiple endocrine neoplasia syndrome type 2 (MEN2). Mouse pheochromocytoma (MPC) cells respond to the Ret-activating ligand GDNF by exhibiting Ret phosphorylation, neurite outgrowth, decreased proliferation, and altered expression of catecholamine biosynthetic enzymes. GDNF exerts similar effects on human pheochromocytoma cells in primary cultures. Ret is minimally expressed by normal mouse chromaffin cells, from which pheochromocytomas are derived. Its expression at high levels by MPC cells suggests possible relationships between two previously unrelated tumor syndromes, neurofibromatosis, and MEN2. The responsiveness of these cells to GDNF suggests that they may be a valuable new model for neurobiology. 相似文献
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Fattal-Valevski A Toledano-Alhadef H Golander A Leitner Y Harel S 《Journal of pediatric endocrinology & metabolism : JPEM》2005,18(7):671-676
BACKGROUND: Intrauterine growth retardation (IUGR) is a major cause of short stature in childhood. Most but not all children experience catch-up growth by 2 years of age. METHODS: We investigated the endocrine profile (thyroid function, prolactin, cortisol, C-peptide and insulin-like growth factor-I [IGF-IJ levels) of 57 children with IUGR, aged 2-10 years, and compared it with 30 controls whose birth weight was appropriate-for-gestational-age. RESULTS: The hormonal profile for both groups was similar for thyroid hormones, prolactin, C-peptide and IGF-I. Cortisol levels were significantly lower in the IUGR group compared to controls (p <0,05). When the IUGR group was divided into 'catch-up' growth and 'non-catch-up' subgroups, the latter had significantly lower IGF-I levels (p <0.001). CONCLUSIONS: Lower cortisol levels in children born with IUGR may reflect impaired function of the hypothalamic-pituitary-adrenal axis associated with this condition. The significantly lower IGF-I levels of the 'non-catch-up' subgroup may be involved in their failure to grow. 相似文献
47.
Briones-Aranda A Rocha L Picazo O 《Progress in neuro-psychopharmacology & biological psychiatry》2005,29(2):275-281
Several stressful factors are able to modify 5-HT1A receptors; for example, different schemes of forced swimming-induced stress (FS) produce a variety of changes in synthesis as well as in 5-HT1A binding in the brain. In addition, it is known that the concentration of 5-HT in the brain is modified as a consequence of acute stressing. The main purpose of this study was to characterize the influence of 15 min of FS on 5-HT levels and on 5-HT1A receptor density in specific brain areas. Mice stressed 24 h before were sacrificed and their brains processed by means of a quantitative autoradiography technique. The following areas were studied: dorsal raphe nucleus (DRN); median raphe nucleus (MRN); thalamus; hypothalamus; amygdala, and hippocampus. 5-HT and 5-hydroxyindolacetic acid (5-HIAA) concentrations in the brainstem, thalamus-hypothalamus, and hippocampus of stressed (ST) mice were analyzed 24 h after stressing by high performance liquid chromatography (HPLC) with fluorometric detection. All data were compared with corresponding unstressed (UST) controls. A significant decrease in 5-HT1A receptor density in DRN, MRN, and hippocampus, accompanied by an increase in labeling of 5-HT1A receptor in thalamus, hypothalamus, and amygdala was observed in ST animals. FS induced a decrease in the 5-HT concentration in the thalamus-hypothalamus, accompanied by an increase in hippocampus areas without affecting 5-HT concentration in the brainstem. Additionally, 5-HIAA/5-HT ratio in the thalamus-hypothalamus area was increased. This study showed that stress alters both 5-HT concentration and 5-HT1A receptors in a region-specific manner. 相似文献
48.
BACKGROUND: The inhabitants of 3 different types of population centers in Israel were assessed as to stress-related symptomatology during 2003 and 2004. These centers have been exposed to 2 distinct forms of violence-sporadic, large-scale terror attacks in the metropolitan areas in the heart of Israel and daily "war-zone" conditions in the settlements beyond the 1967 borders of Israel. METHOD: A semistructured interview and questionnaire survey of a random sample of 314 inhabitants of a suburb of Tel-Aviv, a settlement in the West Bank (Kiryat-Arba), and the Gush-Katif settlement cluster in the Gaza Strip was performed. Symptoms of acute stress and chronic (posttraumatic) stress as well as symptoms of general psychopathology and distress were assessed. RESULTS: The inhabitants of Gush-Katif, in spite of firsthand daily exposure to violent attacks, reported the fewest and least severe symptoms of stress-related complaints, the least sense of personal threat, and the highest level of functioning of all 3 samples. The most severely symptomatic and functionally compromised were the inhabitants of the Tel-Aviv suburb, who were the least frequently and least directly affected by exposure to violent attacks. Because the Gush-Katif population is exclusively religious, the data were reassessed according to religiousness. The religious inhabitants of Kiryat-Arba had almost the same symptom profile as the Gush-Katif population, whereas secular inhabitants of Kiryat-Arba reported faring worse than did either population in the Tel-Aviv suburb. CONCLUSION: Deeply held belief systems affecting life-views may impart significant resilience to developing stress-related problems, even under extreme conditions. Religiousness combined with common ideological convictions and social cohesion was associated with substantial resilience as compared to a secular metropolitan urban population. 相似文献
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