The involvement of calcium and calcium-activated calmodulin (Ca 2ϩ -CaM) in heat shock (HS) signal transduction in wheat (Triticum aestivum) was investigated. Using Fluo-3/acetoxymethyl esters and laser scanning confocal microscopy, it was found that the increase of intracellular free calcium ion concentration started within 1 min after a 37°C HS. The levels of CaM mRNA and protein increased during HS at 37°C in the presence of Ca 2ϩ . The expression of hsp26 and hsp70 genes was up-regulated by the addition of CaCl 2 and down-regulated by the calcium ion chelator EGTA, the calcium ion channel blockers LaCl 3 and verapamil, or the CaM antagonists N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide and chlorpromazine. Treatment with Ca 2ϩ also increased, and with EGTA, verapamil, chlorpromazine, or trifluoperazine decreased, synthesis of HS proteins. The temporal expression of the CaM1-2 gene and the hsp26 and hsp70 genes demonstrated that up-regulation of the CaM1-2 gene occurred at 10 min after HS at 37°C, whereas that of hsp26 and hsp70 appeared at 20 min after HS. A 5-min HS induced expression of hsp26 after a period of recovery at 22°C after HS at 37°C. Taken together, these results indicate that Ca 2ϩ -CaM is directly involved in the HS signal transduction pathway. A working hypothesis about the relationship between upstream and downstream of HS signal transduction is presented.Organisms have developed a diverse array of mechanisms for adapting to environmental changes. One of the best characterized responses is the induction of heat shock proteins (HSPs). The heat shock (HS) response has been found in almost every organism studied to date. The HSPs are synthesized by cells in response to elevated temperature but are also induced by other environmental stresses (Noven et al., 1992; Kilstrup et al., 1997) and play an important role in the thermotolerance of plants (Queitsch et al., 2000; Burke, 2001). A connection between HS response and oxidative stress has been observed (Gong et al., 1997a;Lee et al., 2000;Larkindale and Knight, 2002; Panchuk et al., 2002). The HSPs are divided into several families based on their molecular mass, and most have molecular chaperones functions (for review, see Boston et al., 1996;Miernyk, 1999). Angiosperms synthesize more small HSPs (smHSPs) than other organisms. These smHSPs are likely critical for survival of heat stress and for specific developmental processes in plants (Waters et al., 1996).The changes in cytoplasmic calcium levels act as a ubiquitous signal in eukaryotic cells. HS induced a large increase in intracellular free calcium ion concentration ([Ca 2ϩ ] i ) in Chinese hamster (Cricetulus barabensis) HA-1 fibroblasts (Calderwood et al., 1988). In plants, Gong et al. (1998) observed that HS caused a transient increase in [Ca 2ϩ ] i . The change in [Ca 2ϩ ] i is also involved in regulating the binding activity of the HS transcription factor (HSF) to the HS element (Mosser et al., 1990), the synthesis of HSPs (Kiang et al., 1994;Kuznetsov et al., 1998), and...
Summary Background While the incidence of inflammatory bowel disease (IBD) has stabilised in the West, it is still increasing in several newly industrialised countries. Aims To investigate whether the environmental and dietary risk factors for IBD differ between Eastern and Western populations Methods We systematically searched PubMed, Embase, and Web of Science for studies published from inception through June 30, 2020. Data were pooled using a random effects model. Results Overall, 255 studies were assessed. We identified 25 risk factors for IBD, seven of which were noted in both Eastern and Western populations: family history of Crohn's disease [CD] or ulcerative colitis [UC], former smoking (CD/UC), smoking (CD), appendicectomy (CD), tonsillectomy (CD), meat and meat products (CD), and vitamin D deficiency (UC). The remaining factors, including urban living, current smoking, antibiotics, oral contraceptives, caesarean section, isotretinoin, total energy, fat, cholesterol, fatty acids and their sub‐classifications, eggs, and soft drinks, were associated with an increased risk of IBD in Western or Eastern populations only. We identified 21 protective factors for IBD, among which eight were common in the East and West: farm animals (CD/UC), Helicobacter pylori infection (CD/UC), multiple births (CD), physical activity (CD), history of breastfeeding (CD), pets (UC), current smoking (UC), and coffee intake (UC). Ten factors conferred protection against IBD in Western populations only, whereas eight factors conferred protection against IBD in Eastern populations only. Conclusions Numerous environmental and dietary factors influenced the development of IBD in both Western and Eastern populations, whereas certain factors influenced IBD risk differently in these populations.
Background: This systematic review aimed to investigate whether non-surgical periodontal therapy (NSPT) can reduce systemic inflammatory levels and improve metabolism in patients undergoing haemodialysis (HD) and/or peritoneal dialysis (PD). Methods: Electronic databases (PubMed, EMBASE, CENTRAL, CNKI, and WFPD) were searched for randomized controlled trials (RCTs) performed through July 2019. The risk of bias within studies was assessed with the Cochrane Collaboration's risk assessment tool. The systemic inflammatory and metabolic outcomes included the highly sensitive C-reactive protein (hs-CRP), interleukin 6 (IL-6), tumour necrosis factor-a (TNF-a), the albumin (Alb), and lipid metabolite levels. Meta-analyses (MAs) were performed to calculate the overall effect size where appropriate. Results: Five RCTs were included in this study. Compared with untreated periodontitis groups, the dialysis patients after NSPT significantly showed decreased hs-CRP levels at less than or equal to 2 months (standardized mean difference: − 1.53, 95% confidence interval − 2.95 to − 0.11). No significant difference was found in IL-6 and Alb levels following NSPT at either the 3-or 6-month follow-ups. No MAs could be performed on the TNF-a level and the lipid metabolic markers. Conclusions: NSPT can moderately reduce serum hs-CRP levels in HD and/or PD patients, but did not significantly change IL-6 or Alb levels. For TNF-a and lipid metabolism markers, no sufficient evidence supports that these levels are changed after NSPT. Additional scientific research is necessary to assess the effects of NSPT on systemic inflammation and metabolic parameters in dialysis patients.
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