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Pablo Quintero Margarita Pizarro Nancy Solís Juan Pablo Arab Oslando Padilla Arnoldo Riquelme Marco Arrese 《Journal of physiology and biochemistry》2014,70(3):667-674
Bile acids or its derivatives may influence non-alcoholic fatty liver disease development through multiple mechanisms. Intestinal L-cells secrete glucagon-like peptide-1 (GLP-1) and can be activated by bile acids (BA) influencing insulin resistance and hepatic steatosis development and progression. The aim of the present study was to assess the effects of cholic acid (CA) or ursodeoxycholic acid (UDCA) administration on portal and systemic levels of GLP-1 in genetically obese mice with established hepatic steatosis. Eight-week-old ob/ob mice were fed CA or UDCA during 4 weeks. Systemic and portal GLP-1 levels were measured as well as glucose tolerance test, serum and biliary parameters, hepatic triglyceride content, liver histology, and hepatic gene expression of relevant genes related to bile secretion. Eight-week-old ob/ob mice exhibited marked obesity, hyperinsulinemia, and fasting hyperglycemia. Administration of both CA and UDCA was associated to decreased hepatic triglyceride content and complete reversion of histological steatosis. BA-fed animals did not exhibit significant differences in glucose tolerance. In addition, neither CA nor UDCA administration significantly influenced portal or systemic GLP-1 levels. CA and UDCA strongly ameliorated established fatty liver in ob/ob mice independently of the GLP-1 incretin pathway. Thus, the anti-steatotic action of these bile acids is likely related to direct hepatic effects. 相似文献
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Global change will simultaneously impact many aspects of climate, with the potential to exacerbate the risks posed by plant pathogens to agriculture and the natural environment; yet, most studies that explore climate impacts on plant pathogen ranges consider individual climatic factors separately. In this study, we adopt a stochastic modeling approach to address multiple pathways by which climate can constrain the range of the generalist plant pathogen Phytophthora cinnamomi (Pc): through changing winter soil temperatures affecting pathogen survival; spring soil temperatures and thus pathogen metabolic rates; and changing spring soil moisture conditions and thus pathogen growth rates through host root systems. We apply this model to the southwestern USA for contemporary and plausible future climate scenarios and evaluate the changes in the potential range of Pc. The results indicate that the plausible range of this pathogen in the southwestern USA extends over approximately 200 000 km2 under contemporary conditions. While warming temperatures as projected by the IPCC A2 and B1 emissions scenarios greatly expand the range over which the pathogen can survive winter, projected reductions in spring rainfall reduce its feasible habitat, leading to spatially complex patterns of changing risk. The study demonstrates that temperature and rainfall changes associated with possible climate futures in the southwestern USA have confounding impacts on the range of Pc, suggesting that projections of future pathogen dynamics and ranges should account for multiple pathways of climate–pathogen interaction. 相似文献
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Elizabeth A. Gage-Bouchard Elisa M. Rodriguez Frances G. Saad-Harfouche Austin Miller Deborah O. Erwin 《PloS one》2014,9(10)
Background
Within the field of oncology, increasing access to high quality care has been identified as a priority to reduce cancer disparities. Previous research reveals that the facilities where patients receive their cancer care have implications for cancer outcomes. However, there is little understanding of how patients decide where to seek cancer care. This study examined the factors that shape patients’ pathways to seek their cancer care at a National Cancer Institute-designated comprehensive cancer center (NCI-CCC), and differences in these factors by race, income and education.Methods
In-depth interviews and survey questionnaires were administered to a random sample of 124 patients at one NCI-CCC in the Northeast US. In-depth interview data was first analyzed qualitatively to identify themes and patterns in patients’ pathways to receive their cancer care at an NCI-CCC. Logistic Regression was used to examine if these pathways varied by patient race, income, and education.Results
Two themes emerged: following the recommendation of a physician and following advice from social network members. Quantitative data analysis shows that patient pathways to care at an NCI-CCC varied by education and income. Patients with lower income and education most commonly sought their cancer care at an NCI-CCC due to the recommendation of a physician. Patients with higher income and education most commonly cited referral by a specialist physician or the advice of a social network member. There were no statistically significant differences in pathways to care by race.Conclusions
Our findings show that most patients relied on physician recommendations or advice from a social network member in deciding to seek their cancer care at an NCI-CCC. Due to the role of physicians in shaping patients’ pathways to the NCI-CCC, initiatives that strengthen partnerships between NCI-CCCs and community physicians who serve underserved communities may improve access to NCI-CCCs. 相似文献959.
Sita S. Withers Philip H. Kass Carlos O. Rodriguez Katherine A. Skorupski Danielle O’Brien Teri A. Guerrero Kristen D. Sein Robert B. Rebhun 《Translational oncology》2014,7(3):377-383
Fasting reduces gastrointestinal cellular proliferation rates through G1 cycle blockade and can promote cellular protection of normal but not cancer cells through altered cell signaling including down-regulation of insulin-like growth factor 1 (IGF-1). Consequently, the purpose of this study was to determine the effects of fasting on delayed-type chemotherapy-induced nausea and vomiting in dogs receiving doxorubicin. This prospective randomized crossover study involved intended administration of two doses of doxorubicin. Cancer-bearing dogs were randomized to be fasted for 24 hours beginning at 6 P.M. the night before the first or second doxorubicin administration, and all treatments were administered within an hour before or after 12 P.M. Dogs were fed normally before the alternate dose. Circulating IGF-1 concentrations were determined from serum samples obtained immediately before each doxorubicin treatment. Data from 35 doses were available from 20 dogs enrolled. Dogs that were fasted exhibited a significantly lower incidence of vomiting, when compared to fed dogs (10% compared to 67%, P = .020). Furthermore, among the 15 dogs that completed crossover dosing, vomiting was abrogated in four of five dogs that experienced doxorubicin-induced vomiting when fed normally (P = .050). No differences in other gastrointestinal, constitutional, or bone marrow toxicities or serum IGF-1 levels were observed. 相似文献
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