[Design for online monitoring of occupational hazard factors based on internet of things].

At present, there are disadvantages with the detection for occupational hazard factors, such as insufficient monitoring data, poor timeliness, weak representativeness, long detection cycles, and inability to continuously monitor. Taking advantages of internet of things technology, an online monitoring platform for occupational hazard factors has been designed. The platform collects the concentration (intensity) of hazard factors through sensors, transmits the occupational hazards data collected online in realtime. The online monitoring cloud center for occupational hazard factors processes and analyzes online monitoring data in realtime, stores the hazard factors data to form database management, and provides user application services to form an intelligent online monitoring service model for occupational hazard factors. Based on the online monitoring platform of occupational hazard factors, multi-level government health supervision departments and employers can grasp the status of hazard factors in real time, which is conducive to improving the level of occupational hazard supervision.

[Epidemiological characteristics of an epidemic of 2019-nCoV Omicron variant infection in Beijing].

Objective: To analyze the epidemiological characteristics and transmission chain of an epidemic of COVID-19 in Haidian district, Beijing. Methods: Descriptive epidemiological method was used to analyze the epidemiological characteristics of the epidemic, and field investigation and big data technology were used to analyze the transmission chain of the epidemic. Results: From April 27 to May 13, 2022, an epidemic of COVID-19 occurred in Haidian district. The strains isolated from the cases were identified by whole genome sequencing as Omicron variant (BA.2.2 evolutionary branch). A total of 38 infection cases were detected, including 34 confirmed cases and 4 asymptomatic cases. Most cases were mild ones (88.2%), no severe, critical or death cases occurred. The early clinical symptoms were mainly sore throat (50.0%) and cough (29.4%). The epidemic lasted for 17 days, resulting in 7 generations of the cases and involving 3 community transmissions, 2 working place transmissions and 8 family transmissions; the main infection routes were co-residence (47.6%) and co-space exposure (31.6%). The intergenerational interval M(Q1, Q3)was 3 (1, 6) days. The overall secondary attack rate was 1.5% (37/2 482), and the family secondary attack rate was 36.7% (18/49). Conclusions: The cases in this COVID-19 epidemic caused by Omicron variant had mild clinical symptoms, but the case clustering in families and communities was obvious, the transmission was rapid, and the risk for co-space exposure was high. It is necessary to use information technology to identify close contacts in the local population for the rapid and effective blocking of the epidemic spread.

Theabrownin Induces Cell Apoptosis and Cell Cycle Arrest of Oligodendroglioma and Astrocytoma in Different Pathways.

Theabrownin (TB), a natural compound present in the fresh leaves of green tea, is a potential antitumor agent. However, so far whether and how TB affects glioma is unclear. In this study, we investigated the effect of TB on astroglioma and oligodendroglioma cells. Surprisingly, TB significantly reduced the viabilities of HOG and U251 cells in a dose-dependent manner, which was accompanied by the upregulation of active-Casp-3, Bax, and PTEN; meanwhile, the antiapoptotic gene Bcl-2 was downregulated. In addition, TB treatment induced cell cycle arrest at the G1 and G2/M phases in HOG and U251 cells, respectively. TB treatment caused the downregulating of c-myc, cyclin D, CDK2, and CDK4 and upregulating of p21 and p27 in the HOG cell, while TB increased P53, p21, and p27 levels and decreased the levels of cell cycle regulator proteins such as CDK and cyclin A/B in the U251 cells. Therefore, the c-myc- and P53-related mechanisms were proposed for cell cycle arrest in these two glioma cell lines, respectively. Overall, our findings indicated that TB could be a novel candidate drug for the treatment of gliomas.

MiR-205-3p protects human corneal epithelial cells from ultraviolet damage by inhibiting autophagy via targeting TLR4/NF-κB signaling.

OBJECTIVE: MiRNA has been found to have therapeutic effect on corneal damage. This paper aimed to study the effect of miR-205-3p on corneal damage induced by ultraviolet (UV) radiation. MATERIALS AND METHODS: HCE cells were exposed to UV light and transfected. Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot were used to determine miRNA/mRNA and protein expression. CCK-8 assay, Edu incorporation experiment, and flow cytometry were used to separately measure cell activity, proliferation and apoptosis. LC3 puncta were researched by immunofluorescence experiment. TNF-α, IL-6 and IL-1ß levels in cells were detected by enzyme-linked immunosorbent assay (ELISA) kit. MDA, SOD, and GSH-PX levels were measured using detection kits. Reactive oxygen species (ROS) level was reflected by detecting DCFH-DA density. Luciferase activity assay was performed to verify the regulating relationship between miR-205-3p and TLR4. RESULTS: UV radiation decreased HCE cell viability, proliferation, and increased HCE cell apoptosis and autophagy (all p < 0.01). When exposed UV radiation, the overexpression of miR-205-3p group elevated HCE cells viability, proliferation and weakened HCE cells apoptosis and autophagy (all p < 0.01). MiR-205-3p inhibited inflammation and oxidative stress in HCE cells induced by UV radiation (p < 0.01). MiR-205-3p directly inhibited TLR4 expression. The upregulation of TLR4 significantly reversed the effects of miR-205-3p on HCE cells phenotypes induced by UV radiation (p < 0.01). CONCLUSIONS: MiR-205-3p protected HCE cells from UV damage by inhibiting autophagy via targeting TLR4.

Value of preoperative computed tomography in predicting the local staging of cancer of the tongue at primary surgery.

Preoperative staging is essential for the planning of treatment of cancer. This study was designed to evaluate the accuracy of computed tomography (CT) in predicting the local stage of tongue cancer by comparing it with the gold standard of histopathology. A total of 233 patients with newly-diagnosed tongue cancer was retrospectively reviewed, and the size of the tumour and the status of the cervical lymph node were compared between CT images and histopathological results. Patients with stage II cancer were followed up to assess the influence of inaccurate preoperative staging on prognosis. The accuracy of local staging by CT was 47.6% (111/233), with 59.7% (139/233) for tumour stage, and 70.4% (164/233) for nodal stage. The greatest dimension of the tumour on the CT image was about 2mm less than that measured by histopathology. The estimated volume of tumour was a quarter smaller. The accuracy of predicting malignant lymph nodes by CT was 68.9% (n=161). Among patients with stage II disease, simultaneous neck dissection was less likely in the understaged group than in the accurately staged one. The reoperation rate was a little higher but not significantly so. We conclude that the accuracy of CT in predicting local staging for tongue cancer was only moderate, because it underestimated the size of the tumour and needed to improve the criteria for detecting malignant lymph nodes. Understaging on CT images may influence the prognosis of patients with early stage tongue cancer.

Up-regulation of miR-517-5p inhibits ERK/MMP-2 pathway: potential role in preeclampsia.

OBJECTIVE: To investigate the potential role of miRNA-517-5p in preeclampsia and its underlying mechanism. MATERIALS AND METHODS: Placenta samples were obtained from 20 women with preeclampsia and 20 women with normal pregnancies. Expression level of miR-517-5p in placenta samples and JAR cells was detected. MiRNA-517-5p mimics or inhibitor was transfected in JAR cells, followed by detection of proliferative and invasive abilities of JAR cells. In addition, the expressions of extracellular regulated protein kinases (ERK), phospho-extracellular regulated protein kinases (p-ERK) and matrix metalloproteinase-2 (MMP-2) in JAR cells were evaluated by Western blot. Meanwhile, the mRNA level of MMP-2 was evaluated by Real-time polymerase chain reaction (PCR). The luciferase assay was applied to identify the target gene of miRNA-517-5p. RESULTS: Increased level of miR-517-5p was detected in placenta samples of preeclampsia patients compared with normal pregnancies. MiRNA-517-5p could regulate proliferative and invasive abilities of JAR cells. Furthermore, miRNA-517-5p could regulate ERK/MMP-2 pathway in JAR cells, which would contribute to the pathophysiology of preeclampsia. The luciferase assay showed MMP-2 was the target gene of miR-517-5p. Further studies showed that MMP-2 was dysregulated in preeclampsia. CONCLUSIONS: MiR-517-5p is highly expressed in placenta samples of preeclampsia pregnancies, which could promote proliferative and invasive abilities of JAR cells by inhibiting ERK/MMP-2 pathway.

Involvement of LeMRP, an ATP-binding cassette transporter, in shikonin transport and biosynthesis in Lithospermum erythrorhizon.

Shikonin and its derivatives are important medicinal secondary metabolites accumulating in roots of Lithospermum erythrorhizon. Although some membrane proteins have been identified as transporters of secondary metabolites, the mechanisms underlying shikonin transport and accumulation in L. erythrorhizon cells still remain largely unknown. In this study, we isolated a cDNA encoding LeMRP, an ATP-binding cassette transporter from L. erythrorhizon, and further investigated its functions in the transport and biosynthesis of shikonin using the yeast transformation and transgenic hairy root methods, respectively. Real-time PCR was applied for expression analyses of LeMRP and shikonin biosynthetic enzyme genes. Functional analysis of LeMRP using the heterologous yeast cell expression system showed that LeMRP could be involved in shikonin transport. Transgenic hairy roots of L. erythrorhizon demonstrated that LeMRP overexpressing hairy roots produced more shikonin than the empty vector (EV) control. Real-time PCR results revealed that the enhanced shikonin biosynthesis in the overexpression lines was mainly caused by highly up-regulated expression of genes coding key enzymes (LePAL, HMGR, Le4CL and LePGT) involved in shikonin biosynthesis. Conversely, LeMRP RNAi decreased the accumulation of shikonin and effectively down-regulated expression level of the above genes. Typical inhibitors of ABC proteins, such as azide and buthionine sulphoximine, dramatically inhibited accumulation of shikonin in hairy roots. Our findings provide evidence for the important direct or indirect role of LeMRP in transmembrane transport and biosynthesis of shikonin.

Asymmetrical reproductive interference between two sibling species of tea looper: Ectropis grisescens and Ectropis obliqua.

Ectropis grisescens Warren and Ectropis obliqua (Prout) are two morphologically similar sibling species with overlapping ranges. In this study, manipulative laboratory experiments were conducted to examine the possibility of reproductive interference in sympatric populations of E. grisescens and E. obliqua and the potential consequences of the mating interaction. Our results showed that the presence of males or females of different species could incur mating interference and significant reduction of F 1 offspring. The reduction was not significant relevant to the initial relative abundance of E. grisescens and E. obliqua. Detailed observations of mating opportunity showed that female mating frequencies of both species were not significantly affected by the absolute species density, but the mating success of E. obliqua females with conspecific males depended on species ratio. In addition, adding males to the other species resulted in lower number of offspring suggesting that the males' behaviour might be linked with mating interference. Males of both E. grisescens and E. obliqua could interfere the intraspecific mating of the other species, but the impact of the mating interference differed. These combined data indicated that asymmetric reproductive interference existed in E. grisescens and E. obliqua under laboratory conditions, and the offspring of the mixed species were significantly reduced. The long term outcome of this effect is yet to be determined since additional reproductive factors such as oviposition rate and progeny survival to adulthood may reduce the probability of demographic displacement of one species by the other in overlapping niches.

Osteogenic Treatment Initiating a Tissue-Engineered Cartilage Template Hypertrophic Transition.

Hypertrophic chondrocytes play a critical role in endochondral bone formation as well as the progress of osteoarthritis (OA). An in vitro cartilage hypertrophy model can be used as a platform to study complex molecular mechanisms involved in these processes and screen new drugs for OA. To develop an in vitro cartilage hypertrophy model, we treated a tissue-engineered cartilage template, living hyaline cartilaginous graft (LhCG), with osteogenic medium for hypertrophic induction. In addition, endothelial progenitor cells (EPCs) were seeded onto LhCG constructs to mimic vascular invasion. The results showed that osteogenic treatment significantly inhibited the synthesis of endostatin in LhCG constructs and enhanced expression of hypertrophic marker-collagen type X (Col X) and osteogenic markers, as well as calcium deposition in vitro. Upon subcutaneous implantation, osteogenic medium-treated LhCG constructs all stained positive for Col X and showed significant calcium deposition and blood vessel invasion. Col X staining and calcium deposition were most obvious in osteogenic medium-treated only group, while there was no difference between EPC-seeded and non-seeded group. These results demonstrated that osteogenic treatment was of the primary factor to induce hypertrophic transition of LhCG constructs and this model may contribute to the establishment of an in vitro cartilage hypertrophy model.

Efficacy and safety of miconazole for oral candidiasis: a systematic review and meta-analysis.

The objective of this study is to assess the efficacy and safety of miconazole for treating oral candidiasis. Twelve electronic databases were searched for randomized controlled trials evaluating treatments for oral candidiasis and complemented by hand searching. The clinical and mycological outcomes, as well as adverse effects, were set as the primary outcome criteria. Seventeen trials were included in this review. Most studies were considered to have a high or moderate level of bias. Miconazole was more effective than nystatin for thrush. For HIV-infected patients, there was no significant difference in the efficacy between miconazole and other antifungals. For denture wearers, microwave therapy was significantly better than miconazole. No significant difference was found in the safety evaluation between miconazole and other treatments. The relapse rate of miconazole oral gel may be lower than that of other formulations. This systematic review and meta-analysis indicated that miconazole may be an optional choice for thrush. Microwave therapy could be an effective adjunct treatment for denture stomatitis. Miconazole oral gel may be more effective than other formulations with regard to long-term results. However, future studies that are adequately powered, large-scale, and well-designed are needed to provide higher-quality evidence for the management of oral candidiasis.

Search for a light sterile neutrino at Daya Bay.

A search for light sterile neutrino mixing was performed with the first 217 days of data from the Daya Bay Reactor Antineutrino Experiment. The experiment's unique configuration of multiple baselines from six 2.9 GW(th) nuclear reactors to six antineutrino detectors deployed in two near (effective baselines 512 m and 561 m) and one far (1579 m) underground experimental halls makes it possible to test for oscillations to a fourth (sterile) neutrino in the 10(-3) eV(2)<|Δm(41)(2) |< 0.3 eV(2) range. The relative spectral distortion due to the disappearance of electron antineutrinos was found to be consistent with that of the three-flavor oscillation model. The derived limits on sin(2) 2θ(14) cover the 10(-3) eV(2) ≲ |Δm(41)(2)| ≲ 0.1 eV(2) region, which was largely unexplored.

Spectral measurement of electron antineutrino oscillation amplitude and frequency at Daya Bay.

A measurement of the energy dependence of antineutrino disappearance at the Daya Bay reactor neutrino experiment is reported. Electron antineutrinos (ν¯(e)) from six 2.9 GW(th) reactors were detected with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls. Using 217 days of data, 41 589 (203 809 and 92 912) antineutrino candidates were detected in the far hall (near halls). An improved measurement of the oscillation amplitude sin(2)2θ(13)=0.090(-0.009)(+0.008) and the first direct measurement of the ν¯(e) mass-squared difference |Δm(ee)2|=(2.59(-0.20)(+0.19))×10(-3) eV2 is obtained using the observed ν¯(e) rates and energy spectra in a three-neutrino framework. This value of |Δm(ee)2| is consistent with |Δm(µµ)2| measured by muon neutrino disappearance, supporting the three-flavor oscillation model.

Role of cigarette filter on the risk of oral cancer: a case-control study in a Chinese population.

OBJECTIVE: To determine the role of cigarette filter on the incidence risk of oral squamous cell cancer among male smokers in a Chinese population. SUBJECTS AND METHODS: A multicentric hospital-based case-control study was applied. Three hundred and nineteen male cases and 428 male controls matching for age ( ± 3 years) were identified from January 2008 to December 2010. Detailed smoking histories were obtained by interviews. Logistic regression model was used to compare the influence of filter and non-filter cigarettes on oral cancer risk. RESULTS: The adjusted odd ratios (ORs) for oral cancer were 1.30 (95% CI 1.15, 1.48) of filter cigarette smokers, 2.06 (95% CI 1.17, 3.62) of non-filter cigarette smokers, and 1.73 (95% CI 1.33, 2.25) of mixed smokers, as compared with non-smokers. When classified current smokers according to smoking pack year, the ORs of mixed smokers were 2.27 (95% CI 1.06, 4.85) in <20 pack year, 0.81 (95% CI 0.57, 1.14) in 20-39 pack year, and 0.86 (95% CI 0.57, 1.29) in ≥ 40 pack year, as compared to filter cigarette smokers. CONCLUSIONS: The protective effect against oral cancer of cigarette filter was limited, restricted to smokers of small amount of smoking accumulation. For most smokers, the difference was non-significant between filter and non-filter cigarettes on the risk of developing oral cancer.

Observation of electron-antineutrino disappearance at Daya Bay.

The Daya Bay Reactor Neutrino Experiment has measured a nonzero value for the neutrino mixing angle θ(13) with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GWth reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With a 43,000 ton-GWth-day live-time exposure in 55 days, 10,416 (80,376) electron-antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to expected number of antineutrinos at the far hall is R=0.940±0.011(stat.)±0.004(syst.). A rate-only analysis finds sin(2)2θ(13)=0.092±0.016(stat.)±0.005(syst.) in a three-neutrino framework.

Risk factors and possible mechanisms of intravenous port catheter migration.

OBJECTIVE: To identify the risk factors for catheter migration and demonstrate possible mechanisms of this migration. DESIGN: Retrospective study. SETTING: Chang Gung Memorial Hospital, a tertiary medical centre in Taiwan. PATIENTS: Patients who underwent implantation of intravenous ports via the superior vena cava (SVC). INTERVENTIONS: Procedures involving catheter placement and re-intervention for catheter migration. MAIN OUTCOME MEASURES: The anatomic location of the catheter tip was confirmed by plain chest X-rays (postero-anterior view). From these plain radiographs, the distance (in cm) between the carina and catheter tip and the angle (in degrees) between the locking nut and catheter were measured. METHODS: A total of 1542 procedures related to intravenous port implantation were retrospectively reviewed but only procedures involving implantation via the SVC were included in the analysis. The study group was composed of 31 interventions because of catheter migration, while the control group consisted of 1475 implantation and re-intervention procedures except those involving catheter migrations. RESULTS: Shallow catheter-tip location (p < 0.0001) and the presence of lung cancer (p = 0.006) were risk factors for catheter migration. CONCLUSIONS: Shallow catheter-tip location and the presence of lung cancer are risk factors for catheter migration. Strategies that ensure low catheter-tip location and avoid increased thoracic pressure may be useful preventive measures.

Cloning, expression, purification, and characterization of rat MMP-12.

Macrophage metalloelastase (MMP-12) is implicated in the pathology of many diseases such as emphysema, aortic lesions and cancer. Recently, MMP-12 was cloned and purified from mouse and human macrophages. We report here the expression of the full-length and catalytic domain of rat MMP-12 in Escherichia coli and characterization of the purified enzyme. Inclusion bodies of expressed rat MMP-12 catalytic domain were denatured and refolded using a new method, and then affinity purified to near homogeneity with zinc-chelating Sepharose. The purified rat MMP-12 catalytic domain was highly active in digesting substrates, having a K(m) of 12 microM and optimal pH of 7.5--8.5. During investigation of natural substrate specificity, we found that rat MMP-12 catalytic domain was able to completely degrade collagen-V, partially degrade collagen-I, but it was unable to digest collagen-IV. The enzyme could also degrade osteonectin, vitronectin, and fibronectin, but not laminin and albumin. The catalytic properties and natural substrate specificity of rat MMP-12 catalytic domain differed from those of human MMP-12 catalytic domain.

Study on peripheral blood lymphocytes chromosome abnormality of people exposed to cadmium in environment.

Chromosome aberration (CA) and micronucleus (MN) tests were applied to investigate peripheral blood lymphocytes in 56 people environmentally exposed to cadmium (Cd) for a period up to 30 years, and in 10 unexposed people as controls. As indicator of body-load of Cd, urinary Cd (UCd) concentrations were measured simultaneously. The people in polluted villages were divided into four groups according to various levels of UCd concentrations: -2.5, 2.5-, 5.0-, 10.0- (micrograms/l). There was significant difference in MN rates between the exposed and control groups (3.47, 5.06, 8.06, 12.75/1000 for the exposed groups respectively, and 3.10/1000 for the controls), and significant correlation between MN rates and UCd was observed. Although no marked difference in CA rates was noted between UCd 5.0- and 10.0- groups, there was significant difference in CA rates between the exposed and control groups (3.07, 5.21, 7.21, 8.50% for exposed groups respectively, and 2.33% for the controls) and significant correlation between CA rates and UCd. CA was presented mainly in the form of chromatid and chromosome gaps and breaks. Together with our another study "An Investigation on Human Health Effects by Environmental Cadmium Pollution", the results suggest that Cd may injure human chromosomes and that the damage appears to be concentrated on cytogenetic material and may happen earlier than renal disfunction.

Simple, rapid enzyme-linked immunosorbent assay (ELISA) for the determination of rat osteocalcin.

Determination of the concentration of osteocalcin in rat serum is frequently performed using a commercially available radioimmunoassay (RIA). However, this assay takes 3 days to complete, uses radioactive material, and has a narrow linear range. The limited range of the RIA makes it necessary to test multiple dilutions of the sample which frequently results in values that differ, depending on the dilution. In order to overcome these limitations, we have developed an ELISA that utilizes the same standards and anti-rat osteocalcin antiserum, as is used in the RIA. The principle of the ELISA is that the osteocalcin in the sample competes with osteocalcin previously immobilized on a microtiter plate to bind to the available anti-rat osteocalcin antibodies. The amount of antibody bound to the immobilized osteocalcin is determined colorimetrically using a secondary antibody coupled to alkaline phosphatase. This ELISA has a three-log linear response with a sensitivity of 0.1-0.15 ng/ml and intra- and interassay coefficient of variance (CV) values of less than 10%. Most importantly, the assay is rapid and only requires a 2-hour incubation of the sample with the antiserum. The incubation time is important since we and others have observed a significant decrease in the osteocalcin level from serum samples incubated for long periods of time with the antiserum, presumably due to degradation of the osteocalcin. In general, the commercially available RIA gives osteocalcin values that are one-half to one-fourth that of the ELISA because the RIA requires a 48-hour incubation time.

Design of organic molecules with large two-photon absorption cross sections.

A strategy for the design of molecules with large two-photon absorption cross sections, delta, was developed, on the basis of the concept that symmetric charge transfer, from the ends of a conjugated system to the middle, or vice versa, upon excitation is correlated to enhanced values of delta. Synthesized bis(styryl)benzene derivatives with donor-pi-donor, donor-acceptor-donor, and acceptor-donor-acceptor structural motifs exhibit exceptionally large values of delta, up to about 400 times that of trans-stilbene. Quantum chemical calculations performed on these molecules indicate that substantial symmetric charge redistribution occurs upon excitation and provide delta values in good agreement with experimental values. The combination of large delta and high fluorescence quantum yield or triplet yield exhibited by molecules developed here offers potential for unprecedented brightness in two-photon fluorescent imaging or enhanced photosensitivity in two-photon sensitization, respectively.