118 research outputs found

    GATA2 Mediates Thyrotropin-Releasing Hormone-Induced Transcriptional Activation of the Thyrotropin β Gene

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    Thyrotropin-releasing hormone (TRH) activates not only the secretion of thyrotropin (TSH) but also the transcription of TSHβ and α-glycoprotein (αGSU) subunit genes. TSHβ expression is maintained by two transcription factors, Pit1 and GATA2, and is negatively regulated by thyroid hormone (T3). Our prior studies suggest that the main activator of the TSHβ gene is GATA2, not Pit1 or unliganded T3 receptor (TR). In previous studies on the mechanism of TRH-induced activation of the TSHβ gene, the involvements of Pit1 and TR have been investigated, but the role of GATA2 has not been clarified. Using kidney-derived CV1 cells and pituitary-derived GH3 and TαT1 cells, we demonstrate here that TRH signaling enhances GATA2-dependent activation of the TSHβ promoter and that TRH-induced activity is abolished by amino acid substitution in the GATA2-Zn finger domain or mutation of GATA-responsive element in the TSHβ gene. In CV1 cells transfected with TRH receptor expression plasmid, GATA2-dependent transactivation of αGSU and endothelin-1 promoters was enhanced by TRH. In the gel shift assay, TRH signal potentiated the DNA-binding capacity of GATA2. While inhibition by T3 is dominant over TRH-induced activation, unliganded TR or the putative negative T3-responsive element are not required for TRH-induced stimulation. Studies using GH3 cells showed that TRH-induced activity of the TSHβ promoter depends on protein kinase C but not the mitogen-activated protein kinase, suggesting that the signaling pathway is different from that in the prolactin gene. These results indicate that GATA2 is the principal mediator of the TRH signaling pathway in TSHβ expression

    Corticosteroids for severe sepsis: an evidence-based guide for physicians

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    Septic shock is characterized by uncontrolled systemic inflammation that contributes to the progression of organ failures and eventually death. There is now ample evidence that the inability of the host to mount an appropriate hypothalamic-pituitary and adrenal axis response plays a major in overwhelming systemic inflammation during infections. Proinflammatory mediators released in the inflamed sites oppose to the anti-inflammatory response, an effect that may be reversed by exogenous corticosteroids. With sepsis, via nongenomic and genomic effects, corticosteroids restore cardiovascular homeostasis, terminate systemic and tissue inflammation, restore organ function, and prevent death. These effects of corticosteroids have been consistently found in animal studies and in most recent frequentist and Bayesian meta-analyses. Corticosteroids should be initiated only in patients with sepsis who require 0.5 μg/kg per minute or more of norepinephrine and should be continued for 5 to 7 days except in patients with poor hemodynamic response after 2 days of corticosteroids and with a cortisol increment of more than 250 nmol/L after a standard adrenocorticotropin hormone (ACTH) test. Hydrocortisone should be given at a daily dose of 200 mg and preferably combined to enteral fludrocortisone at a dose of 50 μg. Blood glucose levels should be kept below 150 mg/dL

    Long‐term care facilities' response to the COVID ‐19 pandemic: An international, cross‐sectional survey

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    Aims To (i) assess the adherence of long‐term care (LTC) facilities to the COVID‐19 prevention and control recommendations, (ii) identify predictors of this adherence and (iii) examine the association between the adherence level and the impact of the pandemic on selected unfavourable conditions. Design Cross‐sectional survey. Methods Managers (n = 212) and staff (n = 2143) of LTC facilities (n = 223) in 13 countries/regions (Brazil, Egypt, England, Hong Kong, Indonesia, Japan, Norway, Portugal, Saudi Arabia, South Korea, Spain, Thailand and Turkey) evaluated the adherence of LTC facilities to COVID‐19 prevention and control recommendations and the impact of the pandemic on unfavourable conditions related to staff, residents and residents' families. The characteristics of participants and LTC facilities were also gathered. Data were collected from April to October 2021. The study was reported following the STROBE guidelines. Results The adherence was significantly higher among facilities with more pre‐pandemic in‐service education on infection control and easier access to information early in the pandemic. Residents' feelings of loneliness and feeling down were the most affected conditions by the pandemic. More psychological support to residents was associated with fewer residents' aggressive behaviours, and more psychological support to staff was associated with less work–life imbalance. Conclusions Pre‐pandemic preparedness significantly shaped LTC facilities' response to the pandemic. Adequate psychological support to residents and staff might help mitigate the negative impacts of infection outbreaks. Impact This is the first study to comprehensively examine the adherence of LTC facilities to COVID‐19 prevention and control recommendations. The results demonstrated that the adherence level was significantly related to pre‐pandemic preparedness and that adequate psychological support to staff and residents was significantly associated with less negative impacts of the pandemic on LTC facilities' staff and residents. The results would help LTC facilities prepare for and respond to future infection outbreaks. Patient or public contribution No Patient or Public Contribution
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