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171.
172.
Exposure to high ambient temperature is a stressor that influences both biological and behavioral functions and has been previously shown to have an extensive impact on brain structure and function. Physiological, cellular and behavioral responses to heat-stress (HS) (40–41 °C, 2 h) were evaluated in adult male Sprague-Dawley rats. The effect of HS exposure before predator-scent stress (PSS) exposure (i.e., HS preconditioning) was examined. Finally, a possible mechanism of HS-preconditioning to PSS was investigated. Immunohistochemical analyses of chosen cellular markers were performed in the hippocampus and in the hypothalamic paraventricular nucleus (PVN). Plasma corticosterone levels were evaluated, and the behavioral assessment included the elevated plus-maze (EPM) and the acoustic startle response (ASR) paradigms. Endogenous levels of heat shock protein (HSP)-70 were manipulated using an amino acid (L-glutamine) and a pharmacological agent (Doxazosin). A single exposure to an acute HS resulted in decreased body mass (BM), increased body temperature and increased corticosterone levels. Additionally, extensive cellular, but not behavioral changes were noted. HS-preconditioning provided behavioral resiliency to anxiety-like behavior associated with PSS, possibly through the induction of HSP-70. Targeting of HSP-70 is an attractive strategy for stress-related psychopathology treatment.  相似文献   
173.
Cutaneous squamous cell carcinoma (CSCC) is an epidermal skin cancer that evolves from normal epidermis along several pre-malignant stages. Previously we found specific miRNAs alterations in each step along these stages. miR-199a-3p expression decreases at the transition to later stages. A crucial step for epithelial carcinoma cells to acquire invasive capacity is the disruption of cell–cell contacts and the gain of mesenchymal motile phenotype, a process known as epithelial-to-mesenchymal transition (EMT). This study aims to study the role of decreased expression of miR-199a-3p in keratinocytes’ EMT towards carcinogenesis. First, we measured miR-199a-3p in different stages of epidermal carcinogenesis. Then, we applied Photoactivatable Ribonucleoside-Enhanced Crosslinking and Immunoprecipitation (PAR-CLIP) assay to search for possible biochemical targets of miR-199a-3p and verified that Ras-associated protein B2 (RAP2B) is a bona-fide target of miR-199a-3p. Next, we analyzed RAP2B expression, in CSCC biopsies. Last, we evaluated possible mechanisms leading to decreased miR-199a-3p expression. miR-199a-3p induces a mesenchymal to epithelial transition (MET) in CSSC cells. Many of the under-expressed genes in CSCC overexpressing miR-199a-3p, are possible targets of miR-199a-3p and play roles in EMT. RAP2B is a biochemical target of miR-199a-3p. Overexpression of miR-199a-3p in CSCC results in decreased phosphorylated focal adhesion kinase (FAK). In addition, inhibiting FAK phosphorylation inhibits EMT marker genes’ expression. In addition, we proved that DNA methylation is part of the mechanism by which miR-199a-3p expression is inhibited. However, it is not by the methylation of miR-199a putative promoter. These findings suggest that miR-199a-3p inhibits the EMT process by targeting RAP2B. Inhibitors of RAP2B or FAK may be effective therapeutic agents for CSCC.  相似文献   
174.
Preimplantation genetic testing (PGT) is widely used to select unaffected embryos, increasing the odds of having a healthy baby. During the last few decades, it was accepted that monozygotic dichorionic diamniotic twin pregnancies occurred from the embryo splitting before Day 3 postfertilization according to Corner’s dogma. Hence, the occurrence of a dichorionic diamniotic twin pregnancy after a single blastocyst transfer was considered a dizygotic pregnancy resulting from blastocyst transfer and concurrent natural fertilization. In our study, we have provided for the first time molecular proof that a single blastocyst transfer can result in a monozygotic dichorionic diamniotic twin pregnancy, invalidating Corner’s dogma. In this case, we recommend systematically assessing the genetic status of dichorionic twins after single blastocyst transfer using prenatal diagnosis to exclude the risk from a potential concurrent spontaneous pregnancy and to ensure that both fetuses are unaffected. To achieve this goal, we have developed here an innovative noninvasive prenatal diagnosis by exclusion of paternal variants with droplet digital PCR, maximizing the reliability of genetic diagnosis. Further multicentric prospective studies using genetic testing are now required to establish the rate of blastocyst splitting leading to dichorionic pregnancy in PGT and to identify the risk factors.  相似文献   
175.
The non-receptor focal adhesion kinase (FAK) is highly expressed in the central nervous system during development, where it regulates neurite outgrowth and axon guidance, but its role in the adult healthy and diseased brain, specifically in Alzheimer’s disease (AD), is largely unknown. Using the 3xTg-AD mouse model, which carries three mutations associated with familial Alzheimer’s disease (APP KM670/671NL Swedish, PSEN1 M146V, MAPT P301L) and develops age-related progressive neuropathology including amyloid plaques and Tau tangles, we describe here, for the first time, the in vivo role of FAK in AD pathology. Our data demonstrate that while site-specific knockdown in the hippocampi of 3xTg-AD mice has no effect on learning and memory, hippocampal overexpression of the protein leads to a significant decrease in learning and memory capabilities, which is accompanied by a significant increase in amyloid β (Aβ) load. Furthermore, neuronal morphology is altered following hippocampal overexpression of FAK in these mice. High-throughput proteomics analysis of total and phosphorylated proteins in the hippocampi of FAK overexpressing mice indicates that FAK controls AD-like phenotypes by inhibiting cytoskeletal remodeling in neurons which results in morphological changes, by increasing Tau hyperphosphorylation, and by blocking astrocyte differentiation. FAK activates cell cycle re-entry and consequent cell death while downregulating insulin signaling, thereby increasing insulin resistance and leading to oxidative stress. Our data provide an overview of the signaling networks by which FAK regulates AD pathology and identify FAK as a novel therapeutic target for treating AD.  相似文献   
176.
177.
Despite dramatic improvements in global crop yields over the past half-century, chronic food insecurity persists in many parts of the world. Farming crops for sale (cash cropping) has been recommended as a way to increase income that can, in turn, improve food security for smallholder farmers. Despite long-term efforts by development agencies and government to promote cash cropping, there is limited evidence documenting a relationship between these crops and the food security of households cultivating them. We used a mixed methods approach to build a case study to assess these relationships by collecting quantitative and qualitative data from cacao and oil palm farmers in the Ashanti region of Ghana. Three dimensions of food security were considered: food availability, measured by the months in a year households reported inadequate food; food access, indicated by the coping strategies they employed to secure sufficient food; and food utilization, gauged by the diversity of household diets and anthropometric measurements of child nutritional status. We found significant negative relationships between each of these pillars of food security and a household’s intensity of cash crop production, measured by both quantity and area. A qualitative assessment indicated community perception of these tradeoffs and identified potential mechanisms, including increasing food prices and competing activities for land use, as underlying causes. The adverse relationship between cash crop production and household food security observed in this paper calls for caution; results suggest that positive relationships cannot be assumed, and that further empirical evidence is needed to better understand these tradeoffs.  相似文献   
178.
Relative to the enormous acceptance of the ISO 9000 quality standard, the ISO 14001 environmental management certification has been met with only moderate enthusiasm among industrial facilities. The literature on corporate motivation for ISO 14001 participation is relatively modest considering the enormous number of publications reviewing other aspects of its adoption and implementation. It would seem that the present "marketing" package supporting ISO environmental commitments does not seem to offer sufficiently persuasive incentives for increased sales, either domestically or internationally. While researchers assume that a higher export rate of companies is positively associated with higher ISO participation rates, there have been very few empirical studies that support this inference, and conclusions have not been based on data taken from importing countries orfrom a systematic evaluation of expressed corporate preference for products sold by ISO 14001 certified companies. The present study reports the results of a survey to firms in six countries that are Israel's leading trade partners, importing chemicals, textiles, and produce. The survey results confirm that while the international market still considers price and quality as the paramount factors in selection of suppliers, environmental management systems (EMS) are an important feature that is frequently taken into consideration. EMS certification appears to signify a supplier who is managing the business well and exhibiting ethical responsibility. The European market proved to be more environmentally conscious than those in other industrialized parts of the world. EMS offer a particularly valuable advantage for producers wishing to reach European markets. As policy-makers seek to expand the voluntary adoption of EMS, a clear advantage for exporters should be highlighted among national industries.  相似文献   
179.
All new technologies, including automotive technologies, are first purchased by early adopters. These consumers are currently posed with the choice of purchasing a fuel cell vehicle (FCV) or a variety of other alternatively fueled vehicles, including battery electric vehicles (BEVs). For FCVs to be commercially successful they need to carve out their own niche in the automotive market, something which may prove challenging in the face of strong BEV market growth. The results in this paper come from a questionnaire survey of 470 FCV owners and 1550 BEV owners. The paper explores the socio-economic profile, travel patterns, and attitudes of FCV buyers and compares them to the buyers of BEVs. The result suggests that the adopters of BEVs and FCV are similar in gender, level of education, household income, and have similar travel patterns. They have differences in age, ownership of previous alternative fuel vehicles, attitudes towards sustainability, and more FCV owners live in rented homes and apartment buildings. The results of the study suggest that FCVs may appeal to consumers who live in homes where they cannot recharge a BEV or install their own charger. FCVs still have several challenges to overcome, including the lack of hydrogen refueling stations and a lack of FCV models to choose from.  相似文献   
180.
Current COVID-19 screening efforts mainly rely on reported symptoms and the potential exposure to infected individuals. Here, we developed a machine-learning model for COVID-19 detection that uses four layers of information: (i) sociodemographic characteristics of the individual, (ii) spatio-temporal patterns of the disease, (iii) medical condition and general health consumption of the individual and (iv) information reported by the individual during the testing episode. We evaluated our model on 140 682 members of Maccabi Health Services who were tested for COVID-19 at least once between February and October 2020. These individuals underwent, in total, 264 516 COVID-19 PCR tests, out of which 16 512 were positive. Our multi-layer model obtained an area under the curve (AUC) of 81.6% when evaluated over all the individuals in the dataset, and an AUC of 72.8% when only individuals who did not report any symptom were included. Furthermore, considering only information collected before the testing episode—i.e. before the individual had the chance to report on any symptom—our model could reach a considerably high AUC of 79.5%. Our ability to predict early on the outcomes of COVID-19 tests is pivotal for breaking transmission chains, and can be used for a more efficient testing policy.  相似文献   
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