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From whole organisms to individual cells, responses to environmental conditions are influenced by genetic makeup, where the effect of genetic variation on a trait depends on the environmental context. RNA-sequencing quantifies gene expression as a molecular trait, and is capable of capturing both genetic and environmental effects. In this study, we explore opportunities of using allele-specific expression (ASE) to discover cis-acting genotype-environment interactions (GxE)-genetic effects on gene expression that depend on an environmental condition. Treating 17 common, clinical traits as approximations of the cellular environment of 267 skeletal muscle biopsies, we identify 10 candidate environmental response expression quantitative trait loci (reQTLs) across 6 traits (12 unique gene-environment trait pairs; 10% FDR per trait) including sex, systolic blood pressure, and low-density lipoprotein cholesterol. Although using ASE is in principle a promising approach to detect GxE effects, replication of such signals can be challenging as validation requires harmonization of environmental traits across cohorts and a sufficient sampling of heterozygotes for a transcribed SNP. Comprehensive discovery and replication will require large human transcriptome datasets, or the integration of multiple transcribed SNPs, coupled with standardized clinical phenotyping.

Chemosensory proteins (CSPs) play important roles in chemical communication by insects, as they recognize and transport environmental chemical signals to receptors within sensilla. In this study, we identified HoblCSP1 and HoblCSP2 from a cDNA library of Holotrichia oblita antennae, successfully expressed them in E. coli and purified them by Ni ion affinity chromatography. We then measured the ligand-binding specificities of HoblCSP1 and HoblCSP2 to 50 selected ligands in a competitive binding assay. These results demonstrated that HoblCSP1 and HoblCSP2 have similar ligand-binding spectra. Both proteins displayed the highest affinity for β-ionone, α-ionone and cinnamaldehyde, indicating that they prefer binding to odorants other than sex pheromones. Additionally, immuno-localization revealed that HoblCSP1 is highly concentrated in sensilla basiconica, while HoblCSP2 is specifically localized to sensilla placodea. In conclusion, HoblCSP1 and HoblCSP2 are responsible for binding to general odorants with slightly different specificities due to their different in vivo environments.

Toxoplasma gondii (T. gondii) is an obligate intracellular protozoan parasite that infects a variety of mammals, including humans. An effective vaccine for this parasite is therefore needed. In this study, RH strain T. gondii rhoptry protein 17 was expressed in bacteria as a fusion with glutathione S-transferase (GST) and the recombinant proteins (rTgROP17) were purified via GST-affinity chromatography. BALB/c mice were nasally immunised with rTgROP17, and induction of immune responses and protection against chronic and lethal T. gondii infections were investigated. The results revealed that mice immunised with rTgROP17 produced high levels of specific anti-rTgROP17 IgGs and a mixed IgG1/IgG2a response of IgG2a predominance. The systemic immune response was associated with increased production of Th1 (IFN-γand IL-2) and Th2 (IL-4) cytokines, and enhanced lymphoproliferation (stimulation index, SI) in the mice immunised with rTgROP17. Strong mucosal immune responses with increased secretion of TgROP17-specific secretory IgA (SIgA) in nasal, vaginal and intestinal washes were also observed in these mice. The vaccinated mice displayed apparent protection against chronic RH strain infection as evidenced by their lower liver and brain parasite burdens (59.17% and 49.08%, respectively) than those of the controls. The vaccinated mice also exhibited significant protection against lethal infection of the virulent RH strain (survival increased by 50%) compared to the controls. Our data demonstrate that rTgROP17 can trigger strong systemic and mucosal immune responses against T. gondii and that ROP17 is a promising candidate vaccine for toxoplasmosis.

Acute lung injury (ALI) is the leading cause of death in intensive care units. Extracellular histones have recently been recognized to be pivotal inflammatory mediators. Heparin and its derivatives can bind histones through electrostatic interaction. The purpose of this study was to investigate 1) the role of extracellular histones in the pathogenesis of ALI caused by acid aspiration and 2) whether N-acetyl-heparin (NAH) provides more protection than heparin against histones at the high dose. ALI was induced in mice via intratracheal instillation of hydrochloric acid (HCl). Lethality rate, blood gas, myeloperoxidase (MPO) activity, lung edema and pathological changes were used to evaluate the degree of ALI. Heparin/NAH was administered intraperitoneally, twice a day, for 3 days or until death. Acid aspiration caused an obvious increase in extracellular histones. A significant correlation existed between the concentration of HCl aspirated and the circulating histones. Heparin/NAH (10 mg/kg) improved the lethality rate, blood gas, MPO activity, lung edema and pathological score. At a dose of 20 mg/kg, NAH still provided protection, however heparin tended to aggravate the injury due to hemorrhagic complications. The specific interaction between heparin and histones was verified by the binding assay. In summary, high levels of extracellular histones can be pathogenic in ALI caused by acid aspiration. By neutralizing extracellular histones, heparin/NAH can offer similar protection at the moderate doses. At the high dose, NAH provides better protection than heparin.

It was previously thought that the odorant binding proteins (OBPs) in the sensillum lymph might serve as carriers, which could carry lipophilic odorant molecules to olfactory receptors. In this study, two novel OBP genes of the scarab beetle Holotrichia oblita were screened using an antennal cDNA library. The full cDNA of HoblOBP3 and HoblOBP4 was cloned using reverse transcription PCR and rapid amplification of the cDNA ends. Homology modeling of both OBPs was performed using SWISS-MODEL on-line tools. Next, the two OBPs were expressed in Escherichia coli and purified using Ni ion affinity chromatography. The ligand-binding properties of HoblOBP3 and HoblOBP4 in 42 ligands respectively were measured using the fluorescence probe N-phenyl-naphthylamine (1-NPN). The results obtained from competitive binding assays demonstrated that HoblOBP4 showed a broader range of binding affinities to the test compounds, while HoblOBP3 displays more specific binding affinity. Furthermore, other OBPs and CSPs were expressed in Escherichia coli and purified using Ni ion affinity chromatography. Binding curves were measured for binary mixtures of OBPs and CSPs using 1-NPN, and the Scatchard plots exhibited "J"-like nonlinear correlation trends in some samples. In addition, competitive binding assays of the HoblOBP1 and HoblOBP2 mixtures and of the HoblOBP2 and HoblOBP4 mixtures with representative compounds unexpectedly demonstrated good affinity, which revealed extreme differences that were only obtained using the individual proteins. In the immunocytochemical analysis, colocalization of HoblOBP1 and HoblOBP2, and of HoblOBP2 and HoblOBP4, was detected in the sensilla basiconica and sensilla placodea, respectively. All of these results suggested that HoblOBP1 and HoblOBP2, as well as HoblOBP2 and HoblOBP4, may serve as heterodimers in the sensillum lymph.

2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP) is a member of the interferon-stimulated genes, which includes isoforms CNP1 and CNP2. CNP1 is locally expressed in the myelin sheath but CNP2 is additionally expressed at low levels outside the nervous system. CNPs regulate multiple cellular functions and suppress protein production by association with polyadenylation of mRNA. Polyadenylation of Hepatitis B virus (HBV) RNAs is crucial for HBV replication. Whether CNPs interact with polyadenylation signal of HBV RNAs and interfere HBV replication is unknown. In this study, we evaluated expressions of CNP isoforms in hepatoma cell lines and their effects on HBV replication. We found that CNP2 is moderately expressed and gently responded to interferon treatment in HepG2, but not in Huh7 cells. The CNP1 and CNP2 potently inhibited HBV production by blocking viral proteins synthesis and reducing viral RNAs, respectively. In chronic hepatitis B patients, CNP was expressed in most of HBV-infected hepatocytes of liver specimens. Knockdown of CNP expression moderately improved viral production in the HepG2.2.15 cells treated with IFN-α. In conclusion, CNP might be a mediator of interferon-induced response against HBV.

Objective: To design and evaluate the accuracy of a novel navigation template suitable for posterior cervical screw placement surgery by using 3D printing technology to improve the existing guiding template design. Methods: The researchers (including spine surgeons and technicians) used CT to perform thin-slice scanning on 12 cases of normal upper cervical vertebral specimens and defined the screw channels that were completely located in the pedicle without penetrating the cortex as ideal screw channels, then designed the ideal channel of the upper cervical vertebral (atlantoaxial) pedicle screw by computer software which was regarded as the preset values, and recorded the screw entrance point, transverse angle and sagittal angle of the ideal channel. Then, researchers designed the novel navigation templates for placement pedicle screw according to the ideal screw channel preset values and manufactured them with one for every single vertebra by 3D printer. A senior spine surgeon performed the posterior surgery to implant pedicle screw on the specimens by the novel navigation templates, then performed CT thin-slice scanning on the specimens again after removing the screws, and reconstructed the actual screws channel by computer software, recorded the screw entrance point, transverse angle and sagittal angle of the actual channels which were defined as the actual values and evaluated them according to Kawaguchi’s pedicle screw evaluation standard finally. The differences between the preoperative preset values of ideal screw channel and the postoperative actual values of actual screw channel were compared by a nonparametric paired rank test. Results: 48 screws were placed on 12 cases of upper cervical vertebral specimens in total. It showed that the grade 0, I, II, III channels in this study were 47, 1, 0, 0, respectively. The grade 0 channels accounted for 97.92% of the total number of channels. There was no significant difference with regard to the screw entrance point, the transverse angle, and the sagittal angle between the preoperative preset values of ideal screw channels and the postoperative actual values of actual screw channels. Conclusion: To implant pedicle screw assisted with the novel individually navigation template designed by 3D printed in the posterior cervical surgery can improve accuracy of pedicle screw placement and safety of the surgery. [ABSTRACT FROM AUTHOR]

Membrane proteins play key roles in many fundamental functions in cells including ATP synthesis, ion and molecule transporter, cell signalling and enzymatic reactions, accounting for ~30% genes of whole genomes. However, the hydrophobic nature of membrane proteins frequently hampers the progress of structure determination. Detergent screening is the critical step in obtaining stable detergent-solubilized membrane proteins and well-diffracting protein crystals. Fluorescence Detection Size Exclusion Chromatography (FSEC) has been developed to monitor the extraction efficiency and monodispersity of membrane proteins in detergent micelles. By tracing the FSEC profiles of GFP-fused membrane proteins, this method significantly enhances the throughput of detergent screening. However, current methods to acquire FSEC profiles require either an in-line fluorescence detector with the SEC equipment or an off-line spectrofluorometer microplate reader. Here, we introduce an alternative method detecting the absorption of GFP (FA-SEC) at 485 nm, thus making this methodology possible on conventional SEC equipment through the in-line absorbance spectrometer. The results demonstrate that absorption is in great correlation with fluorescence of GFP. The comparably weaker absorption signal can be improved by using a longer path-length flow cell. The FA-SEC profiles were congruent with the ones plotted by FSEC, suggesting FA-SEC could be a comparable and economical setup for detergent screening of membrane proteins. [ABSTRACT FROM AUTHOR]

The aim of our study is to characterize the venous vasculatures of hepatocellular carcinoma (HCC) using a multi-breath-hold two-dimensional (2D) susceptibility weighted imaging (SWI) in comparison with conventional Magnetic Resonance Imaging (MRI) sequences. Twenty-nine patients with pathologically confirmed HCC underwent MR examination at a 3.0 T scanner. The number of venous vascularity in or around the lesion was counted and the image quality was subjectively evaluated by two experienced radiologists independently based on four image sets: 1) SWI, 2) T1-weighted sequence, 3) T2-weighted sequence, and 4) T1-weighted dynamic contrast-enhanced (DCE) sequence. Of the 29 patients, a total of 33 liver lesions were detected by both SWI and conventional MR sequences. In the evaluation of the conspicuity of venous vascularity, a mean of 10.7 tumor venous vessels per mass was detected by the SWI and 3.9 tumor vasculatures were detected by T1-weighted DCE (P<0.0001), while none was detected by T1-, T2-weighted sequences. The Pearson correlation coefficients between the lesion sizes and the number of tumor vasculatures detected by T1-weighted DCE was 0.708 (P<0.001), and 0.883 by SWI (P<0.001). Our data suggest that SWI appears to be a more sensitive tool compared to T1-weighted DCE sequence to characterize venous vasculature in liver lesions. [ABSTRACT FROM AUTHOR]

Laboratory diagnosis of acute infection of hepatitis E virus (HEV) is commonly based on the detection of HEV RNA, IgM and/or rising IgG levels. However, the profile of these markers when the patients present have not been well determined. To clarify the extent of misdiagnosed sporadic hepatitis E in the initial laboratory detection, serial sera of 271 sporadic acute hepatitis cases were collected, detected and the dynamics of each acute marker during the illness course were analyzed. 91 confirmed cases of hepatitis E were identified based on the presentation of HEV RNA, IgM or at least 4 fold rising of IgG levels. 21 (23.1%) hepatitis E cases were false negative for the viral RNA and 40 (44.0%) for rising IgG, because occurrence of these markers were confined to acute phase of infection and viremia had already subsided and antibody level peaked when these patients presented. IgM was detected in 82 (90.1%) cases. It is the most prevalent of the three markers, because the antibody persisted until early convalescence. Nine cases negative for IgM were positive for rising IgG and one was also positive for the viral RNA; all of these nine cases showed high avid IgG in their acute phase sera, which indicated reinfection. In summary, it is not practicable to determine the true occurrence of sporadic hepatitis E. Nevertheless, it could be closely approximated by approach using a combination of all three acute markers. [ABSTRACT FROM AUTHOR]

Background: Phosphatidic acid (PA) is a key regulated intermediate and precursor for de novo biosynthesis of all glycerophospholipids. PA can be synthesized through the acylation of lysophosphatidic acid (LPA) by 1-acyl-3-phosphate acyltransferase (also called lysophosphatidic acid acyltransferase, LPAAT). Recent findings have substantiated the essential roles of acyltransferases in various biological functions. Methodologies/Principal Findings: We used a flow-injection-based lipidomic approach with ∼200 multiple reaction monitoring (MRM) transitions to pre-screen fatty acyl composition of phospholipids in the yeast Saccharomyces cerevisiae mutants. Dramatic changes were observed in fatty acyl composition in some yeast mutants including Slc1p, a wellcharacterized LPAAT, and Cst26p, a recently characterized phosphatidylinositol stearoyl incorporating 1 protein and putative LPAAT in S. cerevisiae. A comprehensive high-performance liquid chromatography-based multi-stage MRM approach (more than 500 MRM transitions) was developed and further applied to quantify individual phospholipids in both strains to confirm these changes. Our data suggest potential fatty acyl substrates as well as fatty acyls that compensate for defects in both Cst26p and Slc1p mutants. These results were consistent with those from a non-radioactive LPAAT enzymatic assay using C17-LPA and acyl-CoA donors as substrates. Conclusions: We found that Slc1p utilized fatty acid (FA) 18:1 and FA 14:0 as substrates to synthesize corresponding PAs; moreover, it was probably the only acyltransferase responsible for acylation of saturated short-chain fatty acyls (12:0 and 10:0) in S. cerevisiae. We also identified FA 18:0, FA 16:0, FA 14:0 and exogenous FA 17:0 as preferred substrates for Cst26p because transformation with a GFP-tagged CST26 restored the phospholipid profile of a CST26 mutant. Our current findings expand the enzymes and existing scope of acyl-CoA donors for glycerophospholipid biosynthesis. [ABSTRACT FROM AUTHOR]

BACKGROUND:Depression is one of the most common mental disorders, profoundly impacting an individual's performance and quality of life. Due to their unique working conditions, nursing is counted among the occupational groups at high risk for developing depression. Because of the shortage of nursing resources in China, Chinese nurses suffer from heavy daily workloads more than those in many other countries. Therefore, this study aimed to evaluate the overall prevalence of depressive symptoms and analyse the potential risk factors of depressive symptoms in Chinese nurses. METHODS:A systematic literature search in PubMed, EMBASE, Web of Science, the Chinese BioMedical Literature Database (CBM), the China National Knowledge Infrastructure (CNKI), and the Weipu and Wanfang databases up to Dec 31st, 2019 was performed regarding the prevalence of depressive symptoms in Chinese nurses. Eligibility assessment and data extraction were performed independently by 2 researchers, and meta-analysis was used to synthesize the data. Heterogeneity was evaluated using Cochran's Q test and quantified using the I2 statistic. To explore the potential source of heterogeneity, subgroup analyses were also performed. In addition, both funnel plot and Egger's tests were adopted to assess publication bias. RESULTS:A total of 102 studies published from 1996 to 2019 covering 22 provinces were included for further analysis. The total number of participants was 52,592, with a range of 46 to 7205 per study. The overall prevalence of depressive symptoms in Chinese nurses was 43.83% (95%CI: 40.26%-47.42%), and 31.12% (95%CI: 27.30%-35.07%) were classified as mild degrees of depressive symptoms. The prevalence of depressive symptoms may be significantly affected by region, province or municipality and department marital status. Moreover, an increasing trend in the prevalence of depressive symptoms was observed in recent years. CONCLUSION:The results presented a high prevalence of depressive symptoms among Chinese nurses, which suggests interventional programmes by health decision-makers to improving the mental state of nurses is needed urgently, especially in nurses with high risk factors for depressive symptoms. Furthermore, the nationwide investigation of depressive symptoms prevalence should be performed with a standard diagnostic tool, which may be more useful for policy makers and planners.

Efforts to develop peripheral blood-derived nature killer (NK) cells into therapeutic products have been hampered by these cells' low abundance and histoincompatibility. On the other hand, derivation of NK-like cells from more abundant cell sources such as embryonic stem cells (ESCs) and umbilical cord blood (UCB) requires the selection of rare CD34+ cells. Thus, we sought to convert adipose-derived stem cells (ADSCs), which are abundant and natively CD34+, into NK-like cells. When grown in hematopoietic induction medium, ADSCs formed sphere clusters and expressed hematopoietic markers CD34, CD45, and KDR. Further induction in NK cell-specific medium resulted in a population of cells that expressed NK cell marker CD56, and thus termed ADSC-NK. Alternatively, the hematopoietically induced ADSCs were transduced with NK cell-specific transcription factor E4BP4 prior to induction in NK cell-specific medium. This latter population of cells, termed ADSC-NKE, expressed CD56 and additional NK cell markers such as CD16, CD94, CD158, CD314, FasL, and NKp46. ADSC-NKE was as potent as NK leukemia cell NKL in killing breast cancer cell MCF7 and prostate cancer cells DU145, PC3, LnCap, DuPro, C4-2 and CWR22, but exhibited no killing activity toward normal endothelial and smooth muscle cells. In nude mice test ADSC-NKE was able to significantly delay the progression of tumors formed by MCF7 and PC3. When injected into immunocompetent rats, ADSC-NKE was detectable in bone marrow and spleen for at least 5 weeks. Together, these results suggest that ADSCs can be converted into NK-like cells with anti-tumor activities.

BackgroundPhosphatidic acid (PA) is a key regulated intermediate and precursor for de novo biosynthesis of all glycerophospholipids. PA can be synthesized through the acylation of lysophosphatidic acid (LPA) by 1-acyl-3-phosphate acyltransferase (also called lysophosphatidic acid acyltransferase, LPAAT). Recent findings have substantiated the essential roles of acyltransferases in various biological functions.Methodologies/principal findingsWe used a flow-injection-based lipidomic approach with approximately 200 multiple reaction monitoring (MRM) transitions to pre-screen fatty acyl composition of phospholipids in the yeast Saccharomyces cerevisiae mutants. Dramatic changes were observed in fatty acyl composition in some yeast mutants including Slc1p, a well-characterized LPAAT, and Cst26p, a recently characterized phosphatidylinositol stearoyl incorporating 1 protein and putative LPAAT in S. cerevisiae. A comprehensive high-performance liquid chromatography-based multi-stage MRM approach (more than 500 MRM transitions) was developed and further applied to quantify individual phospholipids in both strains to confirm these changes. Our data suggest potential fatty acyl substrates as well as fatty acyls that compensate for defects in both Cst26p and Slc1p mutants. These results were consistent with those from a non-radioactive LPAAT enzymatic assay using C17-LPA and acyl-CoA donors as substrates.ConclusionsWe found that Slc1p utilized fatty acid (FA) 18:1 and FA 14:0 as substrates to synthesize corresponding PAs; moreover, it was probably the only acyltransferase responsible for acylation of saturated short-chain fatty acyls (12:0 and 10:0) in S. cerevisiae. We also identified FA 18:0, FA 16:0, FA 14:0 and exogenous FA 17:0 as preferred substrates for Cst26p because transformation with a GFP-tagged CST26 restored the phospholipid profile of a CST26 mutant. Our current findings expand the enzymes and existing scope of acyl-CoA donors for glycerophospholipid biosynthesis.