Genome-wide identification of GA2ox genes family and analysis of PbrGA2ox1-mediated enhanced chlorophyll accumulation by promoting chloroplast development in pear.

BACKGROUND: Chlorophyll (Chl) is an agronomic trait associated with photosynthesis and yield. Gibberellin 2-oxidases (GA2oxs) have previously been shown to be involved in Chl accumulation. However, whether and how the PbrGA2ox proteins (PbrGA2oxs) mediate Chl accumulation in pear (Pyrus spp.) is scarce. RESULTS: Here, we aimed to elucidate the role of the pear GA2ox gene family in Chl accumulation and the related underlying mechanisms. We isolated 13 PbrGA2ox genes (PbrGA2oxs) from the pear database and identified PbrGA2ox1 as a potential regulator of Chl accumulation. We found that transiently overexpressing PbrGA2ox1 in chlorotic pear leaves led to Chl accumulation, and PbrGA2ox1 silencing in normal pear leaves led to Chl degradation, as evident by the regreening and chlorosis phenomenon, respectively. Meanwhile, PbrGA2ox1-overexpressing (OE) tobacco plants discernably exhibited Chl built-up, as evidenced by significantly higher Pn and Fv/Fm. In addition, RNA sequencing (RNA-seq), physiological and biochemical investigations revealed an increase in abscisic acid (ABA), methyl jasmonate (MeJA), and salicylic acid (SA) concentrations and signaling pathways; a marked elevation in reducing and soluble sugar contents; and a marginal decline in the starch and sucrose levels in OE plants. Interestingly, PbrGA2ox1 overexpression did not prominently affect Chl synthesis. However, it indeed facilitated chloroplast development by increasing chloroplast number per cell and compacting the thylakoid granum stacks. These findings might jointly contribute to Chl accumulation in OE plants. CONCLUSION: Overall, our results suggested that GA2oxs accelerate Chl accumulation by stimulating chloroplast development and proved the potential of PbrGA2ox1 as a candidate gene for genetically breeding biofortified pear plants with a higher yield.

Obeticholic acid improves hepatic steatosis and inflammation by inhibiting NLRP3 inflammasome activation.

BACKGROUND AND AIM: Several pre-clinical and clinical researches have proved that obeticholic acid (OCA)has a potential therapeutic effect on non-alcoholic steatohepatitis (NASH). Our aim was to investigate whether the therapeutic effect of OCA on NASH was attributed to its inhibition effect on cytosolic sensor NLR family pyrin domain containing 3 (NLRP3) inflammasome activation. METHODS: We used mice model of methionine-choline-deficient (MCD) diet induced NASH. At different fibrosis stages, the expressions of NLRP3, caspase-1 and IL-1ß were analyzed by means of immunohistochemistry and western blot respectively. After daily gavage of 0.4 mg of OCA or vehicle for 24 days, we evaluated the direct effect of OCA on NLRP3 inflammasome activation by analyzing the expressions of NLRP3 and IL-1ß. Additionally, liver function and liver histology of mice were assessed. The expressions of NLRP3 and IL-1ß above and the expressions of fibrosis-related genes were analyzed by quantitative real-time polymerase chain reaction (PCR). RESULTS: NLRP3 inflammasome activation could be observed in liver fibrosis, and we found that the expressions of NLRP3, caspase-1 and IL-1ß gradually increased to peak at stage 2-3 but decreased significantly at stage 4 of liver fibrosis in MCD mice model. We also found that short-term OCA treatment could significantly down-regulate the expressions of NLRP3 and IL-1ß and therefore improved NASH-associated steatosis and inflammation. CONCLUSIONS: NLRP3 inflammasome could be activated and might have an essential role in NASH progression, and short-term OCA treatment could have a potential therapeutic effect on NASH-associated steatosis and inflammation by inhibiting NLRP3 inflammasome activation.

A study of the relationship between mental health and menstrual abnormalities in female middle school students from postearthquake Wenchuan.

The present field investigation sought to explore the relationship between mental health and abnormal menstruation in female middle school students from post-earthquake Wenchuan following the 2008 Sichuan earthquake (the earthquake's epicenter was in Wenchuan Couty, Sichuan Province). A total of 587 female middle students from post-earthquake Wenchuan were given the PCL-C, SCL-90, and a menstruation questionnaire. Outcomes were measured by diagnostic criteria. The general incidence of PTSD was 60.8%, and D symptoms were the most prevalent PTSD symptoms (49.6%). Of symptoms indicated by the Symptom Checklist, obsessive-compulsive traits were most prevalent (94.6%), followed by interpersonal sensitivity (91.9%). The incidence of abnormal menstruation was 76.6%. Incidence of abnormal menses among students who screened positive for PTSD was significantly higher than among students who did not (chi2 = 4.015, p = 0.045). The incidence of abnormal menses was higher among students who screened positive for somatization, obsessive-compulsive traits, phobic anxiety, and diet and sleep disorders than among those who did not (p < 0.05). In conclusion, there was a relationship between mental health and physical health in female middle school students in a post-earthquake area. A higher incidence of abnormal menstruation may occur in students with PTSD, somatization disorder, obsessive-compulsive disorder, phobic anxiety, and diet and sleep disorders. Therefore, psychological intervention is particularly necessary for female students who have survived a natural disaster like an earthquake.

[Relationship between post-traumatic stress disorder and perceived social support among middle school students in Wenchuan earthquake-stricken].

OBJECTIVE: To explore the relationship between post-traumatic stress disorder (PTSD) and perceived social support (PSS) ability among middle school students in earthquake-stricken areas after the Wenchuan earthquake accident. METHODS: A total of 1966 students from three secondary schools of Wenchuan earthquake-stricken areas were evaluated by PTSD Checklist-Civilian Version (PCL-C) and Perceived Social Support Scale (PSSS). RESULTS: The overall incidence rate of PTSD was 78.3%, with severe PTSD as 24.38%. Significant differences on the incidence rates of PTSD were found among the students who were in different PSS levels (P < 0.05) and significant negative correlation existed between the levels of severity on PTSD and PSS (gamma = -0.226, P < 0.05). Significant differences on PTSD incidence rates were found among those students who were from different families or out-family PSS levels (P = 0.009, P < 0.05). Significant negative correlation existed between the severity of PTSD and family or out-family PSS level (gamma = -0.176, P < 0.05, gamma = -0.214, P < 0.05). CONCLUSION: Relationships between the incidence rate, severity of PTSD and PSS levels existed among the middle school students in Wenchuan earthquake-stricken areas, with higher PSS, lower incidence rate and lighter severity of PTSD. Psychological intervention for earthquake-stricken students should be carried out.