Chromosome segregation in Archaea : SegA– and SegB–DNA complex structures provide insights into segrosome assembly

Genome segregation is a vital process in all organisms. Chromosome partitioning remains obscure in Archaea, the third domain of life. Here, we investigated the SegAB system from Sulfolobus solfataricus. SegA is a ParA Walker-type ATPase and SegB is a site-specific DNA-binding protein. We determined the structures of both proteins and those of SegA–DNA and SegB–DNA complexes. The SegA structure revealed an atypical, novel non-sandwich dimer that binds DNA either in the presence or in the absence of ATP. The SegB structure disclosed a ribbon–helix–helix motif through which the protein binds DNA site specifically. The association of multiple interacting SegB dimers with the DNA results in a higher order chromatin-like structure. The unstructured SegB N-terminus plays an essential catalytic role in stimulating SegA ATPase activity and an architectural regulatory role in segrosome (SegA–SegB–DNA) formation. Electron microscopy results also provide a compact ring-like segrosome structure related to chromosome organization. These findings contribute a novel mechanistic perspective on archaeal chromosome segregation

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Environmental Consciousness and Green Customer Behavior: The Moderating Roles of Incentive Mechanisms

Consumer awareness of environmental protection and energy conservation concepts has prompted businesses in the hotel industry to adopt green operations. Most studies of the hotel industry have discussed the behavioral intentions (BIs) of consumers based on the theory of planned behavior (TPB), but they have not considered emotional and motivational factors. The present study incorporated two incentive mechanisms and the anticipated positive and negative emotions of consumers into the TPB to explore the relationship between BIs and green hotel development. Structural equation modeling was applied to test the research hypotheses. The results indicate that (1) a positive correlation exists between environmental attitude, subjective norms, perceived behavioral control (PBC), positive anticipated emotion, and desire intention (DI), and a negative correlation exists between negative anticipated emotions and DI; (2) a positive correlation exists between PBC, DI, and BI; and (3) an incentive mechanism has a moderating effect on the relationship between DI and BI

Environmental Consciousness and Green Customer Behavior: The Moderating Roles of Incentive Mechanisms

Consumer awareness of environmental protection and energy conservation concepts has prompted businesses in the hotel industry to adopt green operations. Most studies of the hotel industry have discussed the behavioral intentions (BIs) of consumers based on the theory of planned behavior (TPB), but they have not considered emotional and motivational factors. The present study incorporated two incentive mechanisms and the anticipated positive and negative emotions of consumers into the TPB to explore the relationship between BIs and green hotel development. Structural equation modeling was applied to test the research hypotheses. The results indicate that (1) a positive correlation exists between environmental attitude, subjective norms, perceived behavioral control (PBC), positive anticipated emotion, and desire intention (DI), and a negative correlation exists between negative anticipated emotions and DI; (2) a positive correlation exists between PBC, DI, and BI; and (3) an incentive mechanism has a moderating effect on the relationship between DI and BI

Rejuvenation: Turning Back Time by Enhancing CISD2

The aging human population with age-associated diseases has become a problem worldwide. By 2050, the global population of those who are aged 65 years and older will have tripled. In this context, delaying age-associated diseases and increasing the healthy lifespan of the aged population has become an important issue for geriatric medicine. CDGSH iron-sulfur domain 2 (CISD2), the causative gene for Wolfram syndrome 2 (WFS2; MIM 604928), plays a pivotal role in mediating lifespan and healthspan by maintaining mitochondrial function, endoplasmic reticulum integrity, intracellular Ca2+ homeostasis, and redox status. Here, we summarize the most up-to-date publications on CISD2 and discuss the crucial role that this gene plays in aging and age-associated diseases. This review mainly focuses on the following topics: (1) CISD2 is one of the few pro-longevity genes identified in mammals. Genetic evidence from loss-of-function (knockout mice) and gain-of-function (transgenic mice) studies have demonstrated that CISD2 is essential to lifespan control. (2) CISD2 alleviates age-associated disorders. A higher level of CISD2 during natural aging, when achieved by transgenic overexpression, improves Alzheimer’s disease, ameliorates non-alcoholic fatty liver disease and steatohepatitis, and maintains corneal epithelial homeostasis. (3) CISD2, the expression of which otherwise decreases during natural aging, can be pharmaceutically activated at a late-life stage of aged mice. As a proof-of-concept, we have provided evidence that hesperetin is a promising CISD2 activator that is able to enhance CISD2 expression, thus slowing down aging and promoting longevity. (4) The anti-aging effect of hesperetin is mainly dependent on CISD2 because transcriptomic analysis of the skeletal muscle reveals that most of the differentially expressed genes linked to hesperetin are regulated by hesperetin in a CISD2-dependent manner. Furthermore, three major metabolic pathways that are affected by hesperetin have been identified in skeletal muscle, namely lipid metabolism, protein homeostasis, and nitrogen and amino acid metabolism. This review highlights the urgent need for CISD2-based pharmaceutical development to be used as a potential therapeutic strategy for aging and age-associated diseases

Sex differences in relationships between metabolic syndrome components and factors associated with health-related quality of life in middle-aged adults living in the community: a cross-sectional study in Taiwan

Abstract Background Metabolic syndrome (MetS) is a widespread condition with important effects on public health, in general. There is a lack of relevant research on possible sex differences in the relationship between MetS and health-related quality of life (HRQoL) and also the sex differences in factors associated with HRQoL. The aims of this study were to identify: 1) whether women exhibit greater negative impacts on physical domain HRQoL from MetS compared with men; 2) whether women exhibit greater mental domain impacts compared with men; and 3) whether factors associated with HRQoL scores are different for men and women. Methods This cross-sectional study was conducted in Taipei, Taiwan. Using random sampling, a total of 906 participants aged 35–55 years were recruited. MetS was defined according to the MetS criteria for the Taiwanese population, and HRQoL were assessed using physical component summary (PCS) and mental component summary (MCS) scores of the Short Form Health Survey (SF-36), Taiwan version. Demographics, physical activity, medical history, and blood tests as covariates were recorded and checked. The associations were assessed by multiple linear regression. Results After adjusting for covariates, women but not men with more components of MetS had significantly lower PCS scores (β = − 0.542, p = 0.036). The number of components of MetS was not a significant factor in MCS score differences between the sexes. Furthermore, there were sex differences regarding age, education level, physical activity, and smoking status in association with PCS scores. For MCS scores, sex differences were found in education level, marital status, and habits of smoking and alcohol consumption. Conclusions There were sex differences in the relationships between metabolic syndrome components and factors associated with HRQoL among middle-aged adults living in the community in Taiwan. Further research should be conducted to investigate mechanisms of these sex differences

Effects of early aminophylline therapy on clinical outcomes in premature infants

Background: Aminophylline use and the association between clinical outcomes and therapy timing have been less investigated. The objective of this study was to determine the efficacy of early aminophylline use (within the first two days of life) in premature infants. Method: A retrospective observational cohort of infants weighing <1500 g and <30 weeks of gestational age at Kaohsiung Veterans General Hospital received aminophylline either within the first two days of life (EA, early aminophylline group), after the third day of life (LA, late aminophylline group), or without aminophylline during the first month of life (WA, without aminophylline group). Demographic data and neonatal clinical outcomes were compared among the three groups. Results: This study included 89 preterm infants (EA = 33, LA = 38, WA = 18). The EA group had a lower incidence of bronchopulmonary dysplasia (BPD) than the WA group (adjusted odds ratio [aOR] = 8.86(1.56–59.32); P = 0.024). Although there was no significant difference in BPD incidence between the EA and LA groups (aOR = 2.66(0.51–13.81), P = 0.244), a trend remained. Birth body weight less than 1000 g was also a significant risk factor for BPD (aOR = 8.86(1.32–47.41), P = 0.014). The duration of mechanical ventilation was shorter in the infants in the EA group compared to the WA group (estimated beta = −11.344(-19.57–3.12); P = 0.008). Conclusion: Early aminophylline administration may be associated with a decreased incidence of BPD in preterm infants. However, the clinical benefits of aminophylline treatment require further investigation. In addition, a birth body weight of less than 1000 g was a crucial risk factor for BPD

Long-term outcomes of surgical treatment for intravascular leiomyomatosis

Background: Intravascular leiomyomatosis (IVL) is relatively rare. The optimal surgical method and long-term outcomes are not completely understood. Methods: Medical records between 2007 and 2017 in our hospital were analyzed to identify IVL cases with surgical intervention. Their medical records, operative details, and follow-up were collected by chart review and telephone communication. Results: Eight patients with IVL were included in the study, accounting for 0.26% of all uterine leiomyoma cases. Primary IVL was confined to pelvic cavity in three patients, extended to the inferior vena cava (IVC) below renal vein in one, reached IVC and right atrium in three, and reached main pulmonary artery in one. One-stage operation was performed for seven patients. Cardiopulmonary bypass was done in four patients, and aortic cross-clamp and temporary circulatory arrest was performed in two patients. None of the four patients with intrapulmonary tumors received concomitant pulmonary tumor resection. There was no operative mortality and four morbidities, including ureter injury (2), bladder injury (1), and femoral vein thrombosis (1). During follow-up, two patients exhibited local recurrence of the tumor in the pelvis, and one patient had rapidly growing intrapulmonary tumor three months post-operatively. Intrapulmonary tumors in the other three patients remained stationary at 6, 84, and 120 months post-operatively. Conclusion: One-stage operation to completely remove IVL is feasible and with good long-term outcomes, which is recommended if the patient can tolerate the operation. Concomitant intrapulmonary tumors can be followed up watchfully except when associated with pleural effusion or the pathology indicating trend of increasing malignancy. Keywords: Intravascular leiomyomatosis, Intracardiac leiomyomatosis, Cardiac tumor, Surgery, Cardiopulmonary bypass, Follow-u