Prevalence of occupational heat stress across the seasons and its management amongst healthcare professionals in the UK.

Occupational heat stress (OHS) is an issue in healthcare facilities (HCFs) in the United Kingdom (UK). The aims of this study were to evaluate perceived levels of OHS during two seasons and its perceived consequences on healthcare professionals (HCPs) and to assess the efficacy of heat stress management (HSM) policies. An anonymous online survey was distributed to HCPs working in HCFs in the UK. The survey returned 1014 responses (87% women). Descriptive statistics and content analysis of survey data identified that OHS in HCFs is frequently experienced throughout the year and concerned most HCPs. Over 90% perceived OHS impairs their performance and 20% reported heat-related absenteeism. Awareness of HSM policies was poor and 73% deemed them not adequate. To help reduce the financial loss and impact on staff performance, health and well-being and patient safety, it is recommended that revisions and widespread dissemination of HSM policies are made.

Molecular biomarkers for assessing the heat-adapted phenotype: a narrative scoping review.

Heat acclimation/acclimatisation (HA) mitigates heat-related decrements in physical capacity and heat-illness risk and is a widely advocated countermeasure for individuals operating in hot environments. The efficacy of HA is typically quantified by assessing the thermo-physiological responses to a standard heat acclimation state test (i.e. physiological biomarkers), but this can be logistically challenging, time consuming, and expensive. A valid molecular biomarker of HA would enable evaluation of the heat-adapted state through the sampling and assessment of a biological medium. This narrative review examines candidate molecular biomarkers of HA, highlighting the poor sensitivity and specificity of these candidates and identifying the current lack of a single 'standout' biomarker. It concludes by considering the potential of multivariable approaches that provide information about a range of physiological systems, identifying a number of challenges that must be overcome to develop a valid molecular biomarker of the heat-adapted state, and highlighting future research opportunities.

Amelioration of intestinal barrier function and reduction of blood lead level in adult women with recurrent spontaneous abortion by a novel product of dietary fiber mixture, Holofood.

BACKGROUND: The elevated circulating toxins secondary to the impairment of intestinal barrier integrity commonly elicit a chronic inflammatory response and finally contribute to multiple diseases. These toxins, including bacterial by-products and heavy metals, are the potent risk factors for the development of recurrent spontaneous abortion (RSA). Preclinical evidence suggests that several dietary fibers can restore intestinal barrier function and decrease the accumulation of heavy metals. However, it is uncertain whether treatment with a newly developed blend of dietary fibers product (Holofood) benefits patients with RSA. METHODS: In this trial, we enrolled 70 adult women with RSA, who were randomly assigned into the experiment group and the control group in a 2:1 ratio. Upon the basis of conventional therapy, subjects in the experiment group (n = 48) received 8 weeks oral administration with Holofood three times daily at a dose of 10 g each time. Subjects without Holofood consumption were set as the control (n = 22). Blood samples were collected for the determinations of metabolic parameters, heavy mental lead, and the indices related to intestinal barrier integrity (D-lactate, bacterial endotoxin, and diamine oxidase activity). RESULTS: The reduction amplitude in blood lead from baseline to week 8 was 40.50 ± 54.28 (µg/L) in the experiment group as compared with 13.35 ± 36.81 (µg/L) in the control group (P = 0.037). The decreased level of serum D-lactate from baseline to week 8 was 5.58 ± 6.09 (mg/L) in the experiment group as compared with - 2.38 ± 8.90 (mg/L, P < 0.0001) in the control group. The change in serum DAO activity from baseline to week 8 was 3.26 ± 2.23 (U/L) in the experiment group as compared with - 1.24 ± 2.22 (U/L, P < 0.0001) in the control group. Participants who received Holofood had a greater decline in blood endotoxin from baseline to week 8 than those in the control group. Moreover, by comparing with the self-baseline, Holofood consumption significantly decreased the blood levels of lead, D-lactate, bacterial endotoxin, and DAO activity. CONCLUSION: Our results suggest that Holofood affords a clinically relevant improvements in blood lead level and intestinal barrier dysfunction in patients with RSA.

Validation of the Anti-Inflammatory Effect of Tenebrio Molitor Larva Oil in a Colitis Mouse Model.

Ulcerative colitis is caused by various external factors and is an inflammatory disease that causes decreased intestinal function. Tenebrio molitor larvae contain more than 30 % fat, and the fat component consists of 45 % oleic acid, 20 % linoleic acid and 20 % polyunsaturated fatty acids. In this study, after administering Tenebrio molitor larva oil (TMLO) in a dextran sodium sulphate (DSS)-induced ulcerative colitis mouse model, the pathological findings and inflammatory markers of colitis were analysed to assess whether a colitis mitigation effect was achieved. In the TMLO-administered group, the colon length increased, the spleen weight decreased, and the body weight increased compared with that in the DSS group. In addition, the disease activity index level decreased, the mRNA expression level of inflammatory cytokines in the colon decreased, and the myeloperoxidase activity level significantly decreased. Also, the activity of the NF-κB pathway involved in the regulation of the inflammatory response was lower in the TMLO group than in the DSS group. Taken together, these results suggest that TMLO suppresses occurrence of acute ulcerative colitis in the DSS mouse model. Therefore, TMLO has the potential to be developed as a health food for the prevention and treatment of ulcerative colitis.

Gut Microbiome-Targeted Modulations Regulate Metabolic Profiles and Alleviate Altitude-Related Cardiac Hypertrophy in Rats.

It is well known that humans physiologically or pathologically respond to high altitude, with these responses accompanied by alterations in the gut microbiome. To investigate whether gut microbiota modulation can alleviate high-altitude-related diseases, we administered probiotics, prebiotics, and synbiotics in rat model with altitude-related cardiac impairment after hypobaric hypoxia challenge and observed that all three treatments alleviated cardiac hypertrophy as measured by heart weight-to-body weight ratio and gene expression levels of biomarkers in heart tissue. The disruption of gut microbiota induced by hypobaric hypoxia was also ameliorated, especially for microbes of Ruminococcaceae and Lachnospiraceae families. Metabolome revealed that hypobaric hypoxia significantly altered the plasma short-chain fatty acids (SCFAs), bile acids (BAs), amino acids, neurotransmitters, and free fatty acids, but not the overall fecal SCFAs and BAs. The treatments were able to restore homeostasis of plasma amino acids and neurotransmitters to a certain degree, but not for the other measured metabolites. This study paves the way to further investigate the underlying mechanisms of gut microbiome in high-altitude related diseases and opens opportunity to target gut microbiome for therapeutic purpose. IMPORTANCE Evidence suggests that gut microbiome changes upon hypobaric hypoxia exposure; however, it remains elusive whether this microbiome change is a merely derivational reflection of host physiological alteration, or it synergizes to exacerbate high-altitude diseases. We intervened gut microbiome in the rat model of prolonged hypobaric hypoxia challenge and found that the intervention could alleviate the symptoms of pathological cardiac hypertrophy, gut microbial dysbiosis, and metabolic disruptions of certain metabolites in gut and plasma induced by hypobaric hypoxia. Our study suggests that gut microbiome may be a causative factor for high-altitude-related pathogenesis and a target for therapeutic intervention.

Heat stress and PPE during COVID-19: impact on healthcare workers' performance, safety and well-being in NHS settings.

Personal protective equipment (PPE) can potentiate heat stress, which may have a negative impact on the wearer's performance, safety and well-being. In view of this, a survey was distributed to healthcare workers (HCWs) required to wear PPE during the coronavirus disease 2019 pandemic in the UK to evaluate perceived levels of heat stress and its consequences. Respondents reported experiencing several heat-related illness symptoms, and heat stress impaired both cognitive and physical performance. The majority of respondents stated that wearing PPE made their job more difficult. These, and additional, responses suggest that modification to current working practices is required urgently to improve the resilience of HCWs to wearing PPE during pandemics.

Short-term high-dose gavage of hydroxychloroquine changes gut microbiota but not the intestinal integrity and immunological responses in mice.

AIMS: Hydroxychloroquine (HCQ), a widely used antimalarial drug, is proposed to treat coronavirus disease 2019 (COVID-19). However, no report is currently available regarding the direct effects of HCQ on gut microbiota, which is associated with the outcomes of elderly patients with COVID-19. Here, we first investigated the effects of HCQ on intestinal microecology in mice. MAIN METHODS: Fifteen female C57BL/6J mice were randomly divided into two groups: HCQ group (n = 10) and control group (n = 5). Mice in the HCQ group were administered with HCQ at dose of 100 mg/kg by gavage daily for 14 days. The feces of mice were collected before and on the 7th and 14th days after HCQ challenge, and then analyzed by 16S rRNA amplicon sequencing. At the end of the experiment, the hematology, serum biochemistry and cytokines were determined, respectively. The mRNA expression of tight junction proteins in colonic tissues were also studied by RT-PCR. KEY FINDINGS: HCQ challenge had no effects on the counts of white blood cells, the levels of serum cytokines, and the gene expression of tight junction proteins in colon. HCQ also did not increase the content of serum d-lactate in mice. Notably, HCQ significantly decreased the diversity of gut microbiota, increased the relative abundance of phylum Bacteroidetes whereas decreased that of Firmicutes. SIGNIFICANCE: Short-term high dose HCQ challenge changes gut microbiota but not the intestinal integrity and immunological responses in mice. Special attention should be paid to the effects of HCQ on intestinal microecology in future clinical use.

FCC to BCC transformation-induced plasticity based on thermodynamic phase stability in novel V10Cr10Fe45CoxNi35-x medium-entropy alloys.

We introduce a novel transformation-induced plasticity mechanism, i.e., a martensitic transformation from fcc phase to bcc phase, in medium-entropy alloys (MEAs). A VCrFeCoNi MEA system is designed by thermodynamic calculations in consideration of phase stability between bcc and fcc phases. The resultantly formed bcc martensite favorably contributes to the transformation-induced plasticity, thereby leading to a significant enhancement in both strength and ductility as well as strain hardening. We reveal the microstructural evolutions according to the Co-Ni balance and their contributions to a mechanical response. The Co-Ni balance plays a leading role in phase stability and consequently tunes the cryogenic-temperature strength-ductility balance. The main difference from recently-reported metastable high-entropy dual-phase alloys is the formation of bcc martensite as a daughter phase, which shows significant effects on strain hardening. The hcp phase in the present MEA mostly acts as a nucleation site for the bcc martensite. Our findings demonstrate that the fcc to bcc transformation can be an attractive route to a new MEA design strategy for improving cryogenic strength-ductility.

Early morbidity associated with fasciotomies for acute compartment syndrome in children.

PURPOSE: Acute compartment syndrome (ACS) requires urgent fasciotomy to decompress the relevant muscle compartment/s prior to onset of irreversible myonecrosis and nerve injury. A fasciotomy is not a benign procedure. This study aims to describe and quantify early morbidity directly associated with fasciotomies for ACS in children. METHODS: Clinical charts of 104 children who underwent 112 fasciotomies over a 13-year period at a tertiary children's hospital were reviewed. The following were analyzed: ACS aetiology, fasciotomy site, number of subsequent procedures, method of wound closure, short-term complications and length of hospital stay. RESULTS: Short-term complications included wound infections (6.7%) and the need for blood transfusion (7.7%). Median number of additional operations for wound closure was two (0 to 10) and median inpatient stay was 12 days (3 to 63; SD 11.7). After three unsuccessful attempts at primary closure, likelihood of needing skin grafting for coverage exceeded 80%. Analyses showed that fasciotomy-wound infections were associated with higher risk for four or more closure procedures. Number of procedures required for wound closure correlated with longer inpatient stay as did ACS associated with non-orthopaedic causes. CONCLUSION: Fasciotomy is associated with significant early morbidity, the need for multiple closure operations, and prolonged hospital stay. The decision for fasciotomy needs careful consideration to avoid unnecessary fasciotomies, without increasing the risk of permanent injury from missed or delayed diagnosis. Skin grafting should be considered after three unsuccessful closure attempts. Less invasive tests or continuous monitoring (for high-risk patients) for compartment syndrome may help reduce unnecessary fasciotomies. LEVEL OF EVIDENCE: Level IV, Case series.

Stemmed DNA nanostructure for the selective delivery of therapeutics.

DNA has emerged as a biocompatible biomaterial that may be considered for various applications. Here, we report tumor cell-specific aptamer-modified DNA nanostructures for the specific recognition and delivery of therapeutic chemicals to cancer cells. Protein tyrosine kinase (PTK)7-specific DNA aptamer sequences were linked to 15 consecutive guanines. The resulting aptamer-modified product, AptG15, self-assembled into a Y-shaped structure. The presence of a G-quadruplex at AptG15 was confirmed by circular dichroism and Raman spectroscopy. The utility of AptG15 as a nanocarrier of therapeutics was tested by loading the photosensitizer, methylene blue (MB), to the G-quadruplex as a model drug. The generated MB-loaded AptG15 (MB/AptG15) showed specific and enhanced uptake to CCRF-CEM cells, which overexpress PTK7, compared with Ramos cells, which lack PTK7, or CCRF-CEM cells treated with a PTK7-specific siRNA. The therapeutic activity of MB/AptG15 was tested by triggering its photodynamic effects. Upon 660 nm light irradiation, MB/AptG15 showed greater reactive oxygen species generation and anticancer activity in PTK7-overexpressing cells compared to cells treated with MB alone, those treated with AptG15, and other comparison groups. AptG15 stemmed DNA nanostructures have significant potential for the cell-type-specific delivery of therapeutics, and possibly for the molecular imaging of target cells.

International consensus (ICON) on basic voice assessment for unilateral vocal fold paralysis.

There is a growing need for evaluation tools allowing the quantification of the outcome after voice surgeries. Since the end of the 1990s, multiple unfruitful attempts have been made to reach a consensus, including the Dejonckere protocol for the European Laryngological Society in 2001. This suggested to perform objective and quantifiable measures in the following domains: perception, acoustic, aerodynamic, self-evaluation by the patient and videolaryngostroboscopy. But in a PubMed® search with the keywords "Voice Assessment" and "Voice Outcome" since 2001 retrieving 452 articles, only 33 of them were using methods taking into account the first four dimensions proposed by Dejonckere. To elaborate a new and simpler protocol, we chose to focus on unilateral vocal fold paralyses (UVFP), which represents a homogeneous disease in terms of physiology. This protocol was elaborated on the basis of a review of the literature and of the database and experience of the IFOS panel members. In summary, our group recommends the use and implementation of the ELS "basic protocol" with some minor modifications. Voice audio recordings are an indispensable prerequisite, and may even have medico-legal implications. We recommend the systematic use of the Voice Handicap Index (VHI). Perceptual analysis must be performed by using Hirano's GRB scale and voice breathiness has to be prioritized. Currently, acoustic analysis remains optional given the lack of data to support clinical usefulness. Aerodynamic studies should include at a minimum an evaluation of the Maximum Phonation Time, calculated in seconds following multiple trials in order to obtain a recording representing the patient's best possible glottis closure.

Reduction of plasma glutathione in psychosis associated with schizophrenia and bipolar disorder in translational psychiatry.

The establishment of mechanism-driven peripheral markers is important for translational psychiatry. Many groups, including ours, have addressed molecular alterations in peripheral tissues in association with symptomatic changes in major illnesses. Oxidative stress is implicated in the pathophysiology of schizophrenia (SZ) and bipolar disorder (BP) through studies of patient peripheral tissues and animal models. Although the relationship between peripheral changes and brain pathology remain elusive, oxidative stress may bridge such translational efforts. Nonetheless, the molecular substrates of oxidative stress are not well defined in mental conditions. Glutathione (GSH) is a non-enzymatic antioxidant that eliminates free radicals, and has been suggested to have a role in SZ. We performed a cross-sectional study of 48 healthy controls (CON), 52 SZ patients and 62 BP patients to compare the levels of peripheral GSH by a biochemical enzyme assay. We show a significant reduction of plasma GSH in both SZ and BP patients compared with CON. We evaluated possible influences of clinical characteristics on the level of GSH in SZ and BP. A decrease in GSH level correlated with Positive and Negative Syndrome Scale (PANSS) total and positive scores for SZ and correlated with the PANSS general for BP. Taken together, we provide evidence that SZ and BP display a common molecular signature in the reduction of peripheral GSH in the psychosis dimension.

Cryogenic strength improvement by utilizing room-temperature deformation twinning in a partially recrystallized VCrMnFeCoNi high-entropy alloy.

The excellent cryogenic tensile properties of the CrMnFeCoNi alloy are generally caused by deformation twinning, which is difficult to achieve at room temperature because of insufficient stress for twinning. Here, we induced twinning at room temperature to improve the cryogenic tensile properties of the CrMnFeCoNi alloy. Considering grain size effects on the critical stress for twinning, twins were readily formed in the coarse microstructure by cold rolling without grain refinement by hot rolling. These twins were retained by partial recrystallization and played an important role in improving strength, allowing yield strengths approaching 1 GPa. The persistent elongation up to 46% as well as the tensile strength of 1.3 GPa are attributed to additional twinning in both recrystallized and non-recrystallization regions. Our results demonstrate that non-recrystallized grains, which are generally avoided in conventional alloys because of their deleterious effect on ductility, can be useful in achieving high-strength high-entropy alloys.

False-positive cytopathology results for papillary thyroid carcinoma: A trap for thyroid surgeons.

OBJECTIVES: Current preoperative diagnosis of thyroid nodules remains imperfect despite recent advances in cytopathology and molecular diagnostics. False positivity in preoperative fine-needle aspiration cytology (FNAC) may lead to overtreatment of patients, including total thyroidectomy, and sometimes to lawsuits for misdiagnosis and malpractice. In this study, we analysed clinical characteristics and pathologic findings in patients with false positivity for papillary thyroid carcinoma (PTC) in FNAC. METHODS: We retrospectively reviewed permanent pathology results from 3788 patients who underwent thyroid surgery. Among them, 48 patients had lesions that were deemed suspicious or positive (Bethesda class V or VI) for PTC in preoperative FNAC. We reviewed clinic-pathologic data, radiologic findings and surgical planning in these patients. RESULTS: The prevalence of pathologic thyroiditis was significantly higher among patients with false-positive FNAC results than in those with confirmed PTC (54.2% vs 9.2%, P<.001). The analysis of the permanent pathology reports showed that 26 patients had chronic lymphocytic thyroiditis and 22 patients had no evidence of thyroiditis. Among the patients without pathologic thyroiditis, 19 patients (86.4%) had nodular hyperplasia and three (13.6%) had follicular adenoma, while among the patients with pathologic thyroiditis, seven (26.9%) had no nodule, 14 (53.8%) had nodular hyperplasia, two (7.7%) had hyalinized nodules, two (7.7%) had follicular adenoma and one (3.8%) had a hyalinizing trabecular tumour. In 42 patients, the extent of surgery (total thyroidectomy or hemithyroidectomy) was to be determined according to the intra-operative frozen section biopsy results. Among them, four (10.5%) had inconclusive frozen section results, and 38 (90.5%) had benign results on frozen section. CONCLUSIONS: Patient counselling about the possibility of false positivity is still important. And the presence of thyroiditis might create confusion in the interpretation of cytopathologic results.

Capsaicin attenuates spermatogenic cell death induced by scrotal hyperthermia through its antioxidative and anti-apoptotic activities.

This study was performed to examine whether capsaicin, the main pungent ingredient of red peppers, exerts protective effects against testicular injuries induced by transient scrotal hyperthermia. Capsaicin (0.33 mg kg-1 ) was administered subcutaneously to mice one hour before heat stress (HS) in a 43°C water bath for 20 min. After 7 days, mice exposed to HS showed low testicular weight, severe vacuolisation of seminiferous tubules followed by loss of spermatogenic cells, and appearance of multinucleated giant cells and remarkable TUNEL-positive apoptotic cells, as well as weak immunoreactivity of phospholipid hydroperoxide glutathione peroxidase (PHGPx) in spermatogenic cells. Levels of lipid peroxidation and heat shock 70-kDa protein 1 (Hsp72) and BCL2-associated X protein (Bax) mRNA were greatly increased, but PHGPx, manganese superoxide dismutase (MnSOD), and B-cell lymphoma-extra large (Bcl-xL) mRNAs were significantly diminished in the testes by HS. However, capsaicin pre-treatment significantly suppressed the spermatogenic cell death, oxidative stress (levels of MDA, PHGPx immunoreactivity, and Hsp72, PHGPx, and MnSOD mRNA) and apoptosis (levels of TUNEL-positive cells, and Bcl-xL and Bax mRNA) in testes by HS. These suggest that capsaicin has a protective effect against spermatogenic cell death induced by scrotal hyperthermia through its antioxidative and anti-apoptotic activities.

Identification and characterization of activating ABL1 1b kinase mutations: impact on sensitivity to ATP-competitive and allosteric ABL1 inhibitors.

Although pathologically activated ABL1 fusion kinases represent well-validated therapeutic targets, tumor genomic sequencing has identified numerous point mutations in the ABL1 proto-oncogene of unclear significance. Here we describe ten novel ABL1 1b point mutations, including two from clinical isolates, that cause constitutive kinase activation and cellular transformation. All mutants retained sensitivity to ATP-competitive tyrosine kinase inhibitors (TKIs). Several substitutions cluster near the myristoyl-binding pocket, the target of ABL001, a novel clinically active allosteric kinase inhibitor that mimics the autoinhibitory myristoyl group, and likely activate the kinase by relieving physiologic autoinhibition. In addition, several mutations activate the kinase and confer resistance to allosteric inhibition despite a lack of proximity to this region. We demonstrate that BCR-ABL1 and ABL1 1b point mutations can co-exist in a proportion of clinical cases as a consequence of the chromosome 9 breakpoint location. Collectively, our findings support clinical investigation of ATP-competitive TKIs in malignancies harboring ABL1 point mutations, and sequencing of BCR-ABL1 and ABL1 1b in patients with acquired resistance to allosteric ABL1 inhibitors.

Staphylococcal enterotoxin IgE sensitization in late-onset severe eosinophilic asthma in the elderly.

BACKGROUND: Asthma in the elderly (aged ≥ 65 years old) is a significant concern with high morbidity, but the pathophysiology remains unclear particularly in late-onset asthma. Recent studies suggest staphylococcal enterotoxin IgE (SE-IgE) sensitization to be a risk factor for asthma in general populations; however, the associations have not been examined in late-onset elderly asthma. OBJECTIVE: We aimed to examine the associations of SE-IgE sensitization with late-onset asthma in the elderly, using a database of elderly asthma cohort study. METHODS: A total of 249 elderly patients with asthma and 98 controls were analysed. At baseline, patients were assessed for demographics, atopy, induced sputum profiles and comorbidities including chronic rhinosinusitis (CRS). Serum total IgE and SE-IgE levels were measured. Asthma severity was assessed on the basis of asthma outcomes during a 12-month follow-up period. RESULTS: At baseline, serum SE-IgE concentrations were significantly higher in patients with asthma than in controls [median 0.16 (interquartile range 0.04-0.53) vs. 0.10 (0.01-0.19), P < 0.001]. Elderly asthma patients with high SE-IgE levels had specific characteristics of having more severe asthma, sputum eosinophilia and CRS, compared to those with lower SE-IgE levels. In multivariate logistic regression analyses, the associations between serum SE-IgE concentrations and severe asthma were significant, independently of covariables [SE-IgE-high (≥ 0.35 kU/L) vs. negative (< 0.10 kU/L) group: odds ratio 7.47, 95% confidence interval 1.86-30.03, P = 0.005]. Multiple correspondence analyses also showed that high serum SE-IgE level had close relationships with severe asthma, CRS and sputum eosinophilia together. CONCLUSIONS AND CLINICAL RELEVANCE: This is the first report on the significant associations of SE-IgE sensitization with late-onset asthma in the elderly, particularly severe eosinophilic asthma with CRS comorbidity. Our findings indicate a potential implication of SE in the high morbidity burden of elderly asthma and suggest clues to the pathogenesis of severe late-onset eosinophilic asthma in the elderly.

Overexpression of Selenoprotein SelK in BGC-823 Cells Inhibits Cell Adhesion and Migration.

Effects of human selenoprotein SelK on the adhesion and migration ability of human gastric cancer BGC-823 cells using Matrigel adhesion and transwell migration assays, respectively, were investigated in this study. The Matrigel adhesion ability of BGC-823 cells that overexpressed SelK declined extremely significantly (p < 0.01) compared with that of the cells not expressing the protein. The migration ability of BGC-823 cells that overexpressed SelK also declined extremely significantly (p < 0.01). On the other hand, the Matrigel adhesion ability and migration ability of the cells that overexpressed C-terminally truncated SelK did not decline significantly. The Matrigel adhesion ability and migration ability of human embryonic kidney HEK-293 cells that overexpressed SelK did not show significant change (p > 0.05) with the cells that overexpressed the C-terminally truncated protein. In addition to the effect on Matrigel adhesion and migration, the overexpression of SelK also caused a loss in cell viability (as measured by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide (MTT) colorimetric assay) and induced apoptosis as shown by confocal microscopy and flow cytometry. The cytosolic free Ca2+ level of these cells was significantly increased as detected by flow cytometry. But the overexpression of SelK in HEK-293 cells caused neither significant loss in cell viability nor apoptosis induction. Only the elevation of cytosolic free Ca2+ level in these cells was significant. Taken together, the results suggest that the overexpression of SelK can inhibit human cancer cell Matrigel adhesion and migration and cause both the loss in cell viability and induction of apoptosis. The release of intracellular Ca2+ from the endoplasmic reticulum might be a mechanism whereby the protein exerted its impact. Furthermore, only the full-length protein, but not C-terminally truncated form, was capable of producing such impact. The embryonic cells were not influenced by the elevation of free Ca2+ level in cytosol, probably due to their much greater tolerance to the variation.

Preparation of vesicular stomatitis virus pseudotype with Chikungunya virus envelope protein.

Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes Chikungunya fever (CHIKF) in millions of people mainly in developing countries. CHIKF is characterized by high fever, fatigue, headache, nausea, vomiting, rash, myalgia and severe arthralgia. To date, there is no specific treatment and no licensed vaccine against CHIKV infection. In this study, we developed a safe, efficient and easy neutralization assay of CHIKV based on vesicular stomatitis virus (VSV) pseudotype with CHIKV envelope protein and the green fluorescent protein (GFP) or luciferase as reporter gene, which could be used under a reduced safety level. The VSV pseudotype can be applied to the epidemic survey by measuring the expression of GFP or luciferase activity in infected cells. This system can also be used to study the mechanisms of virus entry.