Psychometric Characteristics of Duke Social Support Index Among Elderly Suicide in Rural China.

We recruited 242 elderly suicides and 242 controls above 60 years to conduct face-to-face interviews by psychological autopsy to examine the psychometric characteristics of the Duke Social Support Index (DSSI) in rural China. DSSI had high internal consistency, with Cronbach's αs of .89 and .90 in suicides and controls, respectively. DSSI was significantly and negatively correlated to loneliness in both samples. Confirmatory factor analysis basically supported the original structure of DSSI, but Item 4 had low factor loading in controls. In conclusion, DSSI has satisfactory reliability and acceptable validity in evaluating social support in the elderly suicide study in China.

Depressive symptom mediates the association between the number of chronic diseases and cognitive impairment: a multi-center cross-sectional study based on community older adults.

Objective: The purpose of this study was to understand the relationship between the multiple chronic conditions (MCC), mental health and cognitive function of older adults in the community, and to propose a hypothesis that depressive symptom mediate the number of chronic diseases and cognitive impairment in older adults. Method: Participants aged 65 years and older from 35 communities in 14 cities in Guangxi, China were recruited. The residents' depressive symptom (PHQ-9) and cognitive status (AD-8) were evaluated, Chi-square test was used to explore the effects of different socio-demographic characteristics on depressive symptom and cognitive impairment. Pearson correlation analysis and the process model 4 were used to explore the relationship between the number of chronic diseases, depressive symptom and cognitive impairment. Result: A total of 11,582 older adults were included in our analysis. The rate of MCC reaching 26.53%. Hypertension combined with diabetes accounts for the highest proportion of two chronic diseases (13.2%). Among the combination of three chronic diseases, the highest incidence of coexisting hypertension combined with cervical/lumbar spondylosis, and rheumatoid arthritis (7.1%). In this study, depression symptoms accounted for 12.9% of older adults aged 65 and above, and cognitive impairment accounted for 27.4%. Female, older age, reside in urban areas, lower educational levels, no spouse, live alone, and MCC were risk factors for depressive symptom and cognitive impairment in older adults (P<0.05). Depressive symptom had a mediating effect in the number of chronic diseases and cognitive impairment, and the mediating effect (1.109) accounted for 44.13% of the total effect (0.247). Conclusion: The mental health of the older adult needs to be taken seriously, and improving depressive symptom can reduce the occurrence of cognitive impairment in older patients with MCC to a certain extent.

Association of polymorphisms in HTR2A, TPH1, and TPH2 genes with attempted suicide in rural China.

OBJECTIVE: We aimed to test the association of polymorphisms in HTR2A, TPH1, and TPH2 genes with attempted suicide in rural China. PARTICIPANTS AND METHODS: On the basis of a case-control study, we recruited 1200 pairs of participants from Shandong Province, China. The blood samples of 712 suicide attempters and 739 nonsuicide attempters were collected finally. We tested seven single nucleotide polymorphisms: rs6313 and rs6311 in HTR2A, rs4537731, rs1800532, and rs1799913 in TPH1, and rs4448731 and rs4641527 in TPH2. RESULTS: In univariate analysis, allele C of rs4537731 was associated negatively with attempted suicide among total and male samples; however, the association was not statistically significant in multivariate analysis after adjusting for other potential confounding factors. No association between other six single nucleotide polymorphisms and attempted suicide was found in the total, male, or female samples. CONCLUSION: This study did not support the effect of these seven serotonergic gene polymorphisms on attempted suicide in rural China.

Identification of Characteristic Fatty Acids to Quantify Triacylglycerols in Microalgae.

The fatty acid profiles of lipids from microalgae are unique. Polyunsaturated fatty acids are generally enriched in polar lipids, whereas saturated and monounsaturated fatty acids constitute the majority of fatty acids in triacylglycerols (TAG). Each species has characteristic fatty acids, and their content is positively or negatively correlated with TAGs. The marine oleaginous diatom Phaeodactylum tricornutum was used as the paradigm to determine the quantitative relationship between TAG and characteristic fatty acid content. Fatty acid profiles and TAG content of Phaeodactylum tricornutum were determined in a time course. C16:0/C16:1 and eicosapentaenoic acid (EPA, C20:5n3) were identified as characteristic fatty acids in TAGs and polar lipids, respectively. The percentage of those characteristic fatty acids in total fatty acids had a significant linear relationship with TAG content, and thus, the correlation coefficient presenting r (2) were 0.96, 0.94, and 0.97, respectively. The fatty acid-based method for TAG quantification could also be applied to other microalgae such as Nannochloropsis oceanica in which the r (2) of C16:0 and EPA were 0.94 and 0.97, respectively, and in Chlorella pyrenoidosa r (2)-values for C18:1 and C18:3 with TAG content were 0.91 and 0.99, repectively. This characteristic fatty acid-based method provided a distinct way to quantify TAGs in microalgae, by which TAGs could be measured precisely by immediate transesterification from wet biomass rather than using conventional methods. This procedure simplified the operation and required smaller samples than conventional methods.

CMKLR1 deficiency maintains ovarian steroid production in mice treated chronically with dihydrotestosterone.

Elevated serum chemerin levels correlate with increased severity of polycystic ovary syndrome (PCOS). However, the role of CMKLR1 signaling in ovarian biology under conditions of excess DHT remains unclear. In this study we compared the effects of continuous 90-day high dose DHT exposure (83.3 □g/day) on wild type and CMKLR1-deficient mice. DHT induced PCOS-like clinical signs in wild type mice as well as significant changes in the expression of hormone receptors, steroid synthesis enzymes, and BMPs and their receptors. In contrast, CMKLR1-deficient mice significantly attenuated DHT-induced clinical signs of PCOS and alterations in ovarian gene expression. To determine whether the BMP4 signaling pathway was involved in the pathogenic effects of CMKLR1 signaling in DHT-induced ovarian steroidogenesis, antral follicles were isolated from wild type and CMKLR1 knockout (KO) mice and treated in vitro with combinations of hCG, DHT, and BMP4 inhibitors. BMP4 inhibition attenuated the induction effects of hCG and DHT on estrogen and progesterone secretion in CMKLR1 KO mice, but not in WT mice, implicating the BMP4 signaling pathway in the CMKLR1-dependent response to DHT. In conclusion, CMKLR1 gene deletion attenuates the effects of chronic DHT treatment on ovarian function in experimental PCOS, likely via BMP4 signaling.

Why we need semisolid decalcification system in bone tissue engineering? A story begins with honeycomb.

The repair of large segmental bone defects remains a tough problem disturbing surgeons and researchers. Bone tissue engineering brings some new sight in this field. However, it has not been effectively applied in clinics, for the reason that the involved mechanism is not well understood. Thus, we need to know the osteogenesis process of the tissue-engineered bone including distribution, proliferation and interaction among seed cells pre-inoculated in biomaterials as well as the function of surrounding tissues. As a matter of fact, the tissue-engineered bone or the biomaterials are solid and opaque, which makes the study difficult. Here, inspired by the structure of honeycomb and amber, we hypothesize a semisolid decalcification protocol to solve this problem.