[Follow-up analysis on change of serum total cholesterol concentration in rural residents in Shanxi province]

Objective: To analyze the longitudinal change of serum total cholesterol concentration in 733 rural residents in Shanxi province. Methods: Based on the residents of five rural areas in Shanxi province who participated in China nutrition and health survey in 2002, a follow-up survey was conducted in 2015. Fasting venous blood of the participants was collected and serum TC concentration was tested by cholesterol oxidase method. Results: Of 733 participants, 332 were male and 401 were female. In 2002 baseline survey, the age of the participants was (42.6±9.5) years old, 76.2% of male and 83.8% of female had junior middle school education or below. Proportion of smoking were 65.7% and 1.2%, drinking were 26.8% and 4.0%, obesity were 6.3% and 12.0%, and central obesity were 27.1% and 31.9%, respectively in male and female. The follow-up age of participants in 2015 was (55.8±9.5) years old, proportion of smoking changed to 48.2% and 1.5%, drinking were 49.7% and 3.0%, obesity increased to 11.8% and 18.2% and central obesity increased to 41.6% and 53.6%, respectively in male and female. The overall serum TC level increased from (3.82±0.89) mmol/L to (4.72±0.97) mmol/L with an average increase of 27.2%, which increased from (3.84±0.94) mmol/L to (4.54±0.93) mmol/L in male with an average increase of 22.7%, and increased from (3.81±0.84) mmol/L to (4.86±0.98) mmol/L in female with an average increase of 30.9%. The serum TC levels in 18-, 30-, 40-, and 50-59 years old group increased from (3.42±0.83), (3.72±0.77), (3.90±0.83) and (4.00±1.03) mmol/L to (4.38±1.01), (4.79±0.92), (4.73±0.99) and (4.76±0.96) mmol/L, with average increase range of 31.4%, 32.1%, 25.2% and 22.6%, respectively. The mean serum TC levels between two years all had statistically significant difference among groups of gender, age, education, marital status, family history of cardiovascular disease, smoking, drinking, BMI and waist circumference after paired t-test and ANOVA analysis (P<0.01). Conclusion: The longitudinal serum TC level of rural residents in Shanxi province increased rapidly.

Adenosine inhibits migration, invasion and induces apoptosis of human cervical cancer cells

Extracellular adenosine is a key signaling molecule which mediates immune suppression, angiogenesis, and regulates cancer cells growth. The effect of adenosine on cervical cancer cells migration and invasion has not been well studied. In the current study, we used Hela and SiHa cell lines to evaluate the effects of adenosine on cervical cancer cells migration, invasion, and apoptosis. The results showed that adenosine treatment inhibited the migration and invasion activities of Hela and SiHa cells. Moreover, by determining the expression of molecules which were involved in epithelial to mesenchymal transition (EMT) progress, we found that epithelial marker E-cadherin was significantly increased in response to adenosine treatment, while the mesenchymal markers including N-cadherin and fibronectin were decreased. These data suggested that adenosine inhibited cervical cancer cells via repressing the EMT progress. The flow cytometry analysis showed that adenosine could also induce cervical cancer cell apoptosis, which mechanism was further confirmed by investigating the expression levels of apoptosis related molecules, via activating mitochondrial apoptosis pathway. These data might suggest that adenosine could be used as an agent for the treatment of cervical cancer.

Identification and characterization of the distinct expression profiles of candidate chemosensory membrane proteins in the antennal transcriptome of Adelphocoris lineolatus (Goeze)

Chemosensory membrane proteins, including odorant receptors (ORs), ionotropic receptors (IRs), gustatory receptors (GRs) and sensory neurone membrane proteins (SNMPs), are supposed to be crucial macromolecules in the insect olfactory signal transduction pathway. The alfalfa plant bug Adelphocoris lineolatus (Goeze) (Hemiptera: Miridae) is highly attracted to high-nitrogen or flowering plants and destroys many important agricultural crops. We assembled the antennal transcriptome of A. lineolatus using Illumina sequencing technology and identified a total of 108 transcripts encoding chemosensory membrane proteins (88 ORs, 12 IRs, four GRs and four SNMPs), amongst which 90 candidates appeared to be full length. Subsequently, both semiquantitative reverse transcription PCR and quantitative real-time PCR experiments were performed to investigate their tissue- and sex-biased expression profiles. The results showed that nearly all of the 108 candidate chemosensory membrane protein genes were largely expressed in adult antennae, and some genes additionally displayed significant differences in the expression levels between sexes. The results of our phylogenetic analysis and the detailed tissue- and sex-biased expression characteristics given here provide an important foundation for further understanding of the complex chemoreception system of the alfalfa plant bug and other Hemiptera species, which also could help us use chemosensory membrane proteins as targets to manipulate insect olfactory behaviour and broaden the applications of available tools for insect pest control.

Effect of SIRT6 knockdown on NF-κB induction and on residual DNA damage in cultured human skin fibroblasts

SIRT6 is a member of the sirtuin family, which is involved in multiple cellular pathways related to aging, inflammation, epigenetics, and a variety of other cellular functions, including DNA repair (1). Multiple pathways involving different cellular functions are impacted by the deacetylase activity of SIRT6. Genomic integrity is maintained by the capacity of SIRT6 to modulate the accessibility of DNA repair proteins. Glucose metabolism is suppressed by SIRT6 via the deacetylation of histones located at the promoter regions of multiple glycolytic genes and the corepression of hypoxia-inducible factor-1α. SIRT6 is also a corepressor of nuclear factor (NF)-κB, silencing NF-κB target genes through the deacetylation of histones at their promoters’ regions. We used SIRT6 small-interfering RNA as a tool to modulate residual DNA damage and NF-κB expression in human dermal fibroblasts. We measured NF-κB levels in the presence or the absence of ultraviolet B (UVB). The impact of SIRT6 knockdown as shown by a decrease in SIRT6 messenger RNA levels resulted in residual DNA damage as evaluated by the comet assay. Our results show that NF-κB was increased significantly (up to 400%) due to SIRT6 silencing in the absence of UVB, illustrating the master regulatory function of SIRT6 in inflammation. We also found a significant increase in DNA damage without UV exposure as a result of SIRT6 silencing, indicating the importance of SIRT6 in DNA repair pathways in cultured human dermal fibroblasts.

FRAILTY, FOOD INSECURITY, AND NUTRITIONAL STATUS IN PEOPLE LIVING WITH HIV

BACKGROUND

Nutritional status and food insecurity are associated with frailty in the general U.S. population, yet little is known about this in the aging population of people living with HIV (PLWH).

OBJECTIVES

Given the potential importance of nutrition and the amenability to intervention, we examined the association between nutritional status, food insecurity, and frailty in PLWH.

DESIGN

Cross sectional study.

SETTING

Boston, Massachusetts, U.S.A.

PARTICIPANTS

50 PLWH, age ≥45 years, recruited from a cohort study examining risk factors for cardiovascular disease.

MEASUREMENTS

Frailty, duration of HIV, use of antiretroviral therapy, disease history, food insecurity, physical function, and physical activity were assessed by questionnaire. Dietary intake was assessed using 3-day food records. Blood was drawn for CD4+ cell count, hemoglobin, hematocrit, and lipid levels. Physical measurements included height, weight, and skinfold thickness.

RESULTS

The prevalence of frailty was 16% (n=8), 44% were pre-frail (n=22) and 40% were not frail (n=20). The number of reported difficulties with 20 activities of daily living was highest in frail (mean 10.4±3.9 SD), followed by pre-frail (6.5±4.6), and lowest in not frail participants (2.0±2.3). Seven (88%) of the frail PLWH lost weight with an average weight loss of 22.9 pounds; 6 (75%) reported unintentional weight loss, and all 6 of these met the frailty criteria for weight loss of 10 or more pounds. Nine (45%) of the not frail PLWH reported losing weight with an average weight loss of 6.2 pounds; 5 (23%) reported unintentional weight loss of <10 pounds. Frail PLWH were more likely to report being food insecure than not frail PLWH (63% vs. 10%, p=0.02), and tended to have lower energy intake than not frail PLWH.

CONCLUSION

Research is needed on targeted interventions to improve food security and activities of daily living in PLWH for both the prevention and improvement of frailty.

Pond sediment magnetite grains show a distinctive microbial community

Formation of magnetite in anaerobic sediments is thought to be enhanced by the activities of iron-reducing bacteria. Geobacter has been implicated as playing a major role, as in culture its cells are often associated with extracellular magnetite grains. We studied the bacterial community associated with magnetite grains in sediment of a freshwater pond in South Korea. Magnetite was isolated from the sediment using a magnet. The magnetite-depleted fraction of sediment was also taken for comparison. DNA was extracted from each set of samples, followed by PCR for 16S bacterial ribosomal RNA (rRNA) gene and HiSeq sequencing. The bacterial communities of the magnetite-enriched and magnetite-depleted fractions were significantly different. The enrichment of three abundant operational taxonomic units (OTUs) suggests that they may either be dependent upon the magnetite grain environment or may be playing a role in magnetite formation. The most abundant OTU in magnetite-enriched fractions was Geobacter, bolstering the case that this genus is important in magnetite formation in natural systems. Other major OTUs strongly associated with the magnetite-enriched fraction, rather than the magnetite-depleted fraction, include a Sulfuricella and a novel member of the Betaproteobacteria. The existence of distinct bacterial communities associated with particular mineral grain types may also be an example of niche separation and coexistence in sediments and soils, which cannot usually be detected due to difficulties in separating and concentrating minerals.

Copy number variation detection using SNP genotyping arrays in three Chinese pig breeds

We performed genome-wide CNV detection based on SNP genotyping data of 96 Chinese-native Tibetan, Dahe and Wuzhishan pigs. These pigs are particularly interesting because of their excellent adaptation to hypoxia or small body size, which facilitates the use of them as models of different human diseases in addition to valuable agricultural animals. A total of 105 CNV regions (CNVRs) were identified, encompassing 16.71 Mb of the pig genome. Seven of 10 (70%) CNVRs selected randomly were validated by quantitative real-time PCR. Comparison with previous studies revealed 25 (23.81%) novel CNVRs, indicating that CNV coverage of the pig genome is still incomplete and there exists large diversity between pig breeds. Functional analysis of genes located in these CNVRs confirmed the high representation of genes involved in sensory perception, neurological system processes and other basic metabolic processes. In addition, the majority of these CNVRs were detected to span reported pig QTL that affect various traits, which highlighted three biologically interesting genes with copy number changes (i.e., ANKRD34B, FAM110B and ABCG1). These genes may have economic importance in pig breeding and are worth being further investigated. We also obtained some CNVRs harboring genes that had human orthologs involved in human diseases such as cardiovascular disease and Alzheimer's disease. The findings of this study are a significant extension of the coverage of CNVRs in the pig genome and provide valuable resources for follow-up-associated studies of CNVs in pig complex traits as well as important implications of human diseases.

Partial least squares based gene expression analysis in posttraumatic stress disorder

OBJECTIVE

Posttraumatic stress disorder (PTSD) is an adverse psychological response to traumatic events. Microarray technology for large-scale gene expression analysis facilitates the identification of signatures that underlie the pathogenesis of PTSD. Previous studies mostly used variance/regression analysis without considering array specific factors. We aim to investigate the underlying mechanism of PTSD through partial least squares (PLS) based analysis.

MATERIALS AND METHODS

With a gene expression profile data set for 17 chronic PTSD patients and 16 controls recovered from psychological trauma from the Gene Expression Omnibus (GEO) database, we performed Partial Least Square (PLS) based analysis.

RESULTS

We acquired 230 down-regulated genes and 335 up-regulated genes. Significantly increased representations of dysregulated genes in immune, endocrine and nervous pathways were identified. Among the top 5 hub genes in the network, PRKCA has been reported to be related with PTSD before. Three other genes, TP53, EP300 and CALM1 might also contribute to the pathogenesis of PTSD since they are all related with other neuronal disorders.

CONCLUSIONS

Our findings shed light on expression signatures of PTSD with the hope to give further theoretical supports for future therapeutic study.

Sequence variations at I260 and A1731 contribute to persistent currents in Drosophila sodium channels

Tetrodotoxin-sensitive persistent sodium currents, INaP, that activate at subthreshold voltages, have been detected in numerous vertebrate and invertebrate neurons. These currents are believed to be critical for regulating neuronal excitability. However, the molecular mechanism underlying INaP is controversial. In this study, we identified an INaP with a broad range of voltage dependence, from -60mV to 20mV, in a Drosophila sodium channel variant expressed in Xenopus oocytes. Mutational analysis revealed that two variant-specific amino acid changes, I260T in the S4-S5 linker of domain I (ILS4-S5) and A1731V in the voltage sensor S4 of domain IV (IVS4), contribute to the INaP. I260T is critical for the portion of INaP at hyperpolarized potentials. The T260-mediated INaP is likely the result of window currents flowing in the voltage range where the activation and inactivation curves overlap. A1731V is responsible for impaired inactivation and contributes to the portion of INaP at depolarized potentials. Furthermore, A1731V causes enhanced activity of two site-3 toxins which induce persistent currents by inhibiting the outward movement of IVS4, suggesting that A1731V inhibits the outward movement of IVS4. These results provided molecular evidence for the involvement of distinct mechanisms in the generation of INaP: T260 contributes to INaP via enhancement of the window current, whereas V1731 impairs fast inactivation probably by inhibiting the outward movement of IVS4.

Molecular characterization of HMW-GS 1Dx3(t) and 1Dx4(t) genes from Aegilops tauschii and their potential value for wheat quality improvement

Two x-type high molecular weight glutenin subunits (HMW-GS) in Aegilops tauschii, 1Dx3(t) and 1Dx4(t) were identified by SDS-PAGE and MALDI-TOF-MS. Their complete coding sequences were isolated by AS-PCR. 1Dx3(t) and 1Dx4(t) genes consist of 2535 bp and 2508 bp and encode 845 and 836 amino acid residues, respectively. The deduced molecular masses of 1Dx3(t) and 1Dx4(t) gene products are 87655.26 Da and 86664.24 Da, respectively, well corresponding to the molecular masses measured by MALDI-TOF-MS. A total of 18 SNPs were identified between 1Dx3(t) and 1Dx4(t). Comparing with 1Dx5 subunit, 1Dx3(t) had a six amino acid insertion at 146-151 while the 1Dx4(t) had a nine amino acid deletion when compared with 1Dx3(t) subunit. The authenticity of the cloned 1Dx3(t) and 1Dx4(t) genes were confirmed by successful expression of their ORFs in E. coli. Comparison and phylogenetic tree based on the amino acid and nucleotide sequences confirmed that 1Dx3(t) was most closely related to 1Dx5 subunit that is widely accepted as a superior subunit for bread-making property. The secondary structure prediction demonstrated that 1Dx3(t) subunit has significantly high α-helix and β-strand contents, suggesting it might have positive effects on dough quality.