Sp1 Controls the Basal Level of Interleukin-34 Transcription.

Interleukin-34 (IL-34) is a cytokine that plays important roles at steady state and in diseases. The induced or inhibited expression of IL-34 by stimuli has been deeply investigated. However, the regulation of IL-34 basal expression is largely unknown. The aim of this study is to investigate whether IL-34 expression is regulated by a general transcription factor Specificity Protein 1 (Sp1) at transcription level. By using bioinformatic software, four putative Sp1-binding sites overlapping GC boxes were found in the core promoter region of IL-34. Alignment of the core promoter sequences of mammalian IL-34 showed GC box-C (-62/-57) and D (-11/-6) were conserved in some mammals. Luciferase assay results showed that only deletion of GC box-C (-62/-57) significantly reduced luciferase activities of IL-34 core promoter in SH-SY5Y cells. By using electrophoretic mobility shift assay (EMSA), it was found that Sp1 specifically interacted with GC box-C sequence CCCGCC (-62/-57) in the core promoter of IL-34. By using chromatin immunoprecipitation (ChIP), it was discovered that Sp1 bound to the core promoter of IL-34 in living cells. In addition, silencing of Sp1 expression by its specific siRNA reduced IL-34 mRNA and protein levels significantly in SH-SY5Y cells. Likewise, IL-34 expression was inhibited in a dose-dependent manner by a Sp1 inhibitor Plicamycin. Furthermore, silencing of Sp1 also downregulated mRNA and protein expression of IL-34 in GES-1 and 293T cell lines, suggesting that IL-34 transcription regulated by Sp1 was not cell-type specific. Taken together, these results indicate that Sp1 controls the basal level of IL-34 transcription.

Identification of necroptosis-related genes for predicting prognosis and exploring immune infiltration landscape in colon adenocarcinoma.

Background: Necroptosis is a recently discovered form of cell death that plays an important role in the occurrence and development of colon adenocarcinoma (COAD). Our study aimed to construct a risk score model to predict the prognosis of patients with COAD based on necroptosis-related genes. Methods: The gene expression data of COAD and normal colon samples were obtained from the Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx). The least absolute shrinkage and selection operator (LASSO) Cox regression analysis was used to calculate the risk score based on prognostic necroptosis-related differentially expressed genes (DEGs). Based on the risk score, patients were classified into high- and low-risk groups. Then, nomogram models were built based on the risk score and clinicopathological features. Otherwise, the model was verified in the Gene Expression Omnibus (GEO) database. Additionally, the tumor microenvironment (TME) and the level of immune infiltration were evaluated by "ESTIMATE" and single-sample gene set enrichment analysis (ssGSEA). Functional enrichment analysis was carried out to explore the potential mechanism of necroptosis in COAD. Finally, the effect of necroptosis on colon cancer cells was explored through CCK8 and transwell assays. The expression of necroptosis-related genes in colon tissues and cells treated with necroptotic inducers (TNFα) and inhibitors (NEC-1) was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). Results: The risk score was an independent prognostic risk factor in COAD. The predictive value of the nomogram based on the risk score and clinicopathological features was superior to TNM staging. The effectiveness of the model was well validated in GSE152430. Immune and stromal scores were significantly elevated in the high-risk group. Moreover, necroptosis may influence the prognosis of COAD via influencing the cancer immune response. In in-vitro experiments, the inhibition of necroptosis can promote proliferation and invasion ability. Finally, the differential expression of necroptosis-related genes in 16 paired colon tissues and colon cancer cells was found. Conclusion: A novel necroptosis-related gene signature for forecasting the prognosis of COAD has been constructed, which possesses favorable predictive ability and offers ideas for the necroptosis-associated development of COAD.

Spatiotemporal distribution of the atmospheric 14C around Ningde NPP.

In this paper, the sampling and monitoring methods of atmospheric 14C around Ningde NPP were presented, and the variations and trends during 2013-2021 were statistically analyzed and comparatively studied with worldwide reported values around NPPs. Meanwhile, the correlation study with the gaseous effluent emission amount from Ningde NPP was analyzed, and the spatial distribution of the atmospheric 14C around Ningde NPP was simulated with the atmospheric release based on the long-term meteorological parameters with the plume diffusion model. It was shown that the average specific activity of atmospheric 14C at each sampling site ranged from 229 to 230 mBq/gC, and the weak evidence of influence on the nearest sampling site from the release of the NPP could be observed. Seasonal variations of 14C specific activity were analyzed, and it was shown that, except for the site 1.7 km from the NPP, the specific activity of the atmospheric 14C was higher in summer and autumn and lower in winter and spring. Besides, it was shown that the excess 14C for long-term monitoring results around the NPP was consistent with the simulated values on the order of magnitude.

SAMHD1, positively regulated by KLF4, suppresses the proliferation of gastric cancer cells through MAPK p38 signaling pathway.

SAMHD1 was reported to be related with the development of tumors, while its function in gastric cancer (GC) has not been elucidated yet. Here, we investigated the role and mechanism of SAMHD1 in regulating the proliferation of GC, as well as the mechanism of its expression regulation. Our results revealed that SAMHD1 was downregulated in GC tissues and cell lines, which was correlated with tumor size, depth of invasion and TNM stage. Overexpression of SAMHD1 inhibited the proliferation, clone formation, DNA synthesis and cell cycle progression, while knockdown of SAMHD1 promoted the proliferation of GC cells in vitro and vivo. Meanwhile, SAMHD1 inhibited the activation of MAPK p38 signaling pathway. Moreover, SB203580, as a MAPK p38 inhibitor, could reverse the proliferation and activation of MAPK p38 signaling pathway caused by knockdown of SAMHD1 in GC cells. Additionally, transcription factor Krüppel-like factor 4 (KLF4) bound to the core promoter of SAMHD1, increasing its transcriptional expression in GC cells. In conclusion, SAMHD1 suppressed the proliferation of GC through negatively regulating the activation of MAPK p38 signaling pathway and was upregulated by KLF4 in GC cells.

Affordable measures to monitor and alarm nosocomial SARS-CoV-2 infection due to poor ventilation.

Since the coronavirus disease 2019 (COVID-19) outbreak, the nosocomial infection rate worldwide has been reported high. It is urgent to figure out an affordable way to monitor and alarm nosocomial infection. Carbon dioxide (CO2 ) concentration can reflect the ventilation performance and crowdedness, so CO2 sensors were placed in Beijing Tsinghua Changgung Hospital's fever clinic and emergency department where the nosocomial infection risk was high. Patients' medical records were extracted to figure out their timelines and whereabouts. Based on these, site-specific CO2 concentration thresholds were calculated by the dilution equation and sites' risk ratios were determined to evaluate ventilation performance. CO2 concentration successfully revealed that the expiratory tracer was poorly diluted in the mechanically ventilated inner spaces, compared to naturally ventilated outer spaces, among all of the monitoring sites that COVID-19 patients visited. Sufficient ventilation, personal protection, and disinfection measures led to no nosocomial infection in this hospital. The actual outdoor airflow rate per person (Qc ) during the COVID-19 patients' presence was estimated for reference using equilibrium analysis. During the stay of single COVID-19 patient wearing a mask, the minimum Qc value was 15-18 L/(s·person). When the patient was given throat swab sampling, the minimum Qc value was 21 L/(s·person). The Qc value reached 36-42 L/(s·person) thanks to window-inducted natural ventilation, when two COVID-19 patients wearing masks shared the same space with other patients or healthcare workers. The CO2 concentration monitoring system proved to be effective in assessing nosocomial infection risk by reflecting real-time dilution of patients' exhalation.

AI-assisted CT imaging analysis for COVID-19 screening: Building and deploying a medical AI system.

The sudden outbreak of novel coronavirus 2019 (COVID-19) increased the diagnostic burden of radiologists. In the time of an epidemic crisis, we hope artificial intelligence (AI) to reduce physician workload in regions with the outbreak, and improve the diagnosis accuracy for physicians before they could acquire enough experience with the new disease. In this paper, we present our experience in building and deploying an AI system that automatically analyzes CT images and provides the probability of infection to rapidly detect COVID-19 pneumonia. The proposed system which consists of classification and segmentation will save about 30%-40% of the detection time for physicians and promote the performance of COVID-19 detection. Specifically, working in an interdisciplinary team of over 30 people with medical and/or AI background, geographically distributed in Beijing and Wuhan, we are able to overcome a series of challenges (e.g. data discrepancy, testing time-effectiveness of model, data security, etc.) in this particular situation and deploy the system in four weeks. In addition, since the proposed AI system provides the priority of each CT image with probability of infection, the physicians can confirm and segregate the infected patients in time. Using 1,136 training cases (723 positives for COVID-19) from five hospitals, we are able to achieve a sensitivity of 0.974 and specificity of 0.922 on the test dataset, which included a variety of pulmonary diseases.

Clinical features of pediatric patients with COVID-19: a report of two family cluster cases.

BACKGROUND: Coronovirus disease 2019 (COVID-19) has spread rapidly across the globe. People of all ages are susceptible to COVID-19. However, literature reports on pediatric patients are limited. METHODS: To improve the recognition of COVID-19 infection in children, we retrospectively reviewed two confirmed pediatric cases from two family clusters. Both clinical features and laboratory examination results of the children and their family members were described. RESULTS: The two confirmed children only presented with mild respiratory or gastrointestinal symptoms. Both of them had normal chest CT images. After general and symptomatic treatments, both children recovered quickly. Both families had travel histories to Hubei Province. CONCLUSIONS: Pediatric patients with COVID-19 are mostly owing to family cluster or with a close contact history. Infected children have relatively milder clinical symptoms than infected adults. We should attach importance to early recognition, early diagnosis, and early treatment of infected children.

A correlation study of continuously monitored gamma dose rate and meteorological conditions.

In this paper, the correlations between the continuously monitored gamma dose rate (GDR) and meteorological parameters, including precipitation, air temperature, relative humidity, air pressure, wind direction, and wind speed, were analyzed by using one year of the hourly dataset from a monitoring system with ten stations. The correlation coefficients are varied by the range of each meteorological parameter. Precipitation would enhance the GDR up to 84%, which is highly related to precipitation intensity and ground type. Strong and positive correlation between the GDR and light precipitation was identified, while the correlation was reduced with increasing of precipitation. Air temperature could cause a fluctuation of the average GDR within the range 1.8-5.3 nGy h-1, and different correlation characteristics were indicated for low and high air temperature. The GDR was positively correlated with relative humidity, though relative humidity is inversely correlated with air temperature. Correlations between the GDR and air pressure were mainly negative. Diurnal variations between the GDR and the air temperature, relative humidity, and air pressure were also analyzed. The wind played an important role also in the fluctuation of the GDR with the GDR difference up to 2.00 nGy h-1 averaged from the sixteen wind-directions. Lower GDR can be found in the direction of prevailing wind because of the dilution effect of the radon progenies in the surface air. In this paper, some exploratory interpretation of physical influence mechanisms of meteorological parameters on the GDR was also presented, which suggests further work should be carried out to explore the variation and correlation principle.

Novel epitopes identified from Mycobacterium tuberculosis antigen Rv2629induces cytotoxic T lymphocyte response.

There is an urgent need for a more effective vaccine against tuberculosis (TB). Cytotoxic T lymphocytes (CTLs) play a critical role in combating Mycobacterium tuberculosis (M.tb). The identification of novel CTL epitopes is essential for the design of peptide-based vaccines. In this study, we predicted CTL epitope peptides of M.tb antigen Rv2629 restricted by HLA-A2, using bioinformatics methods. The affinity and stability of binding of these peptides with HLA-A2 molecules were detected by flow cytometry. Their ability to induce CTLs generation was determined in peripheral blood mononuclear cells (PBMCs) from healthy uninfected subjects, Latent tuberculosis infection (LTBI) subjects, and TB patients ex vivo. The cytotoxic activity induced by the epitope peptides was tested by lactate dehydrogenase (LDH) release assay. Finally, we found four novel CTL epitope peptides, Rv2629-p190-2L, Rv2629-p190-1Y2L, Rv2629-p274, and Rv2629-p315, which had high-affinity and stability of binding with T2 cells. Their ability of inducing CTLs was highest in PBMCs from TB patients (P < 0.05). In addition, these peptides could induce the CTLs to generate specific cytotoxic activity. They showed higher immunogenicity in TB patients and had the potential to become candidate vaccines for TB therapy.

Conformational Bias by a Removable Silyl Group: Construction of Bicyclo[n.3.1]alkenes by Ring Closing Metathesis.

Herein, we report a novel strategy based on a conformationally controlled RCM by a removable silyl group, which allows the facile synthesis of various bicyclo[n.3.1]alkenes, especially a set of highly strained bicyclo[5.3.1]alkenes. Further derivatizations of the silyl group and the resultant double bond of bicyclo[5.3.1]undecene 2 f enabled a concise synthesis of A-B-C ring skeleton of taxol. Density functional theory (DFT) calculations suggest that the introduction of a bulky silyl group at C-5 position of the 1,3-dialkenylcyclohexanol substrates dramatically lowers the energy bias gap between diaxial conformers (to RCM) and diequatorial conformers (to cross metathesis), thereby favoring the expected RCM reaction to give the challenging bridged molecules.

Magnetic beads-based DNAzyme recognition and AuNPs-based enzymatic catalysis amplification for visual detection of trace uranyl ion in aqueous environment.

We herein developed a novel biosensor for the visual detection of trace uranyl ion (UO2(2+)) in aqueous environment with high sensitivity and specificity by using DNAzyme-functionalized magnetic beads (MBs) for UO2(2+) recognition and gold nano-particles (AuNPs)-based enzymatic catalysis oxidation of TMB (3,3',5,5'-tetramethylbenzidine sulfate) for signal generation. The utilization of MBs facilitates the magnetic separation and collection of sensing system from complex sample solution, which leads to more convenient experimental operation and more strong resistibility of the biosensor to the matrix of sample, and the utilization of AuNPs-based enzymatic catalysis amplification greatly improved the sensitivity of the biosensor. Compared with the previous DNAzyme-based UO2(2+) sensors, the proposed biosensor has outstanding advantages such as relative high sensitivity and specificity, operation convenience, low cost and more strong resistibility to the matrix of sample. It can be used to detect as low as 0.02 ppb (74 pM) of UO2(2+) in aqueous environment by only naked-eye observation and 1.89 ppt (7.0 pM) of UO2(2+) by UV-visible spectrophotometer with a recovery of 93-99% and a RSD ≤ 5.0% (n=6) within 3h. Especially, the visual detection limit of 0.02 ppb (74 pM) is much lower than the maximum allowable level of UO2(2+) (130 nM) in the drinking water defined by the U.S. Environmental Protection Agency (EPA), indicating that our method meets the requirement of rapid and on-site detection of UO2(2+) in the aqueous environment by only naked-eye observation.

[Prediction of Antigen Epitopes of Associated Protein Rv2004c Latent-infected by Mycobacterium Tuberculosis].

To screen new tuberculosis diagnostic antigens and vaccine candidates,we predicted the epitopes of Mycobacterium tuberculosis latent infection-associated protein Rv2004 cby means of bioinformatics.The homology between Rv2004 cprotein and human protein sequences was analyzed with BLAST method.The second structures,hydrophilicity,antigenicity,flexibility and surface probability of the protein were analyzed to predict B cell epitopes and T cell epitopes by Protean software of DNAStar software package.The Th epitopes were predicted by RANKPEP and SYFPEITHI supermotif method,the CTL epitopes were predicted by means of combination analyses of SYFPEITHI supermotif method,BIMAS quantitative motif method and NetCTL prediction method.The peptide sequences with higher scores were chosen as the candidate epitopes.Blast analysis showed that Rv2004 cprotein had low homology with human protein.This protein had abundant secondary structures through analysis of DNAStar software,the peptide segments with high index of hydrophilicity,antigenicity,surface probability and flexibility were widely distributed and were consistent with segments having beta turn or irregular coil.Ten candidates of B cell epitopes were predicted.The Th epitopes of Rv2004 cprotein were located after the 200 th amino acid.Of 37 Th cell epitopes predicted,there were more epitopes of HLA-DRB1*0401and HLA-DRB1*0701phenotypes,and the MHC restrictive types of some Th cell epitopes exist cross overlap.Of 10 CTL epitopes predicted,there were more number and higher score of HLA-A2 restricted epitopes.Therefore MycobacteriumtuberculosisRv2004 cprotein is a protein antigen with T cell and B cell epitopes,and is expected to be a new target protein candidate for tuberculosis diagnosis and vaccine.

A turn-off fluorescent biosensor for the rapid and sensitive detection of uranyl ion based on molybdenum disulfide nanosheets and specific DNAzyme.

A novel fluorescent biosensor for detecting uranyl ion (UO2(2+)) in aqueous environment has been developed based on the specific recognition of DNAzyme and the fluorescence quenching ability of molybdenum disulfide (MoS2) nanosheets. The DNAzyme contains a DNA enzyme strand and a 6-carboxylfluorescein (FAM)-labeled DNA substrate strand. We demonstrated that MoS2 nanosheets have low affinity to the substrate-enzyme complex DNAzyme. Whereas, in the presence of UO2(2+), UO2(2+) can specifically cleave DNAzyme to release FAM-labeled single-strand DNA and the released FAM-labeled single-strand DNA can be firmly adsorbed on the surface of MoS2 nanosheets, which resulted in an obvious decrease of fluorescence intensity. This provided a sensing platform for the rapid, simple and sensitive fluorescent detection of UO2(2+). By using the sensing platform, a sensitive and selective fluorescent method for the rapid detection of UO2(2+) has been developed. In comparison with previous biosensor, the proposed method has obvious analytical advantage such as relatively high sensitivity and good stability, short analytical time and low cost. It can be used to detect as low as 2.14 nM of UO2(2+) in aqueous environment with a recovery of 96-102% and a RSD<5% (n=6). The success of this study provides a promising alternative for the rapid and on-site detection of UO2(2+) in environmental monitoring.

Development of poly(N-isopropylacrylamide)/alginate copolymer hydrogel-grafted fabrics embedding of berberine nanosuspension for the infected wound treatment.

In the present study, a novel hydrogel-grafted fabrics embedding of berberine nanosuspension was developed for the treatment of infected wound. Hydrogel-grafted fabric was prepared by graft copolymerization of N-isopropylacrylamide and alginate using ceric ammonium nitrate as initiator. Berberine nanosuspension was prepared and embedded in the hydrogel-grafted fabrics to achieve sustained drug release. The prepared hydrogel-grafted fabrics embedding of berberine nanosuspension was characterized by FT-IR spectroscopy, scanning electron microscopy, and swelling degree studies. Fourier transform infrared spectroscopy revealed that berberine was embedded into the matrix of hydrogel-grafted fabrics, rather than on the surface. Scanning electron microscopy showed that a thin hydrogel layer was formed on the surface of nonwoven fibers. The swelling study showed that hydrogel-grafted fabric had water absorbing characteristic with reversible temperature sensitivity. The drug release study demonstrated that hydrogel-grafted fabrics can be used as a sustained drug delivery system of hydrophobic compounds. The berberine nanosuspension embedded hydrogel-grafted fabric was further investigated in an animal infected wound model and was found to be a very promising wound healing dressing for the treatment and healing of infected wounds.

Establishing a serologic decision tree model of extrapulmonary tuberculosis by MALDI-TOF MS analysis.

Matrix-assisted laser desorption-ionization time of flight mass spectrometry (MALDI-TOF MS) combined with weak cationic exchange (WCX) magnetic beads was used to establish a decision tree model that distinguished extrapulmonary tuberculosis (EPTB) from non-EPTB individuals. Eight-one patients with EPTB and 112 non-EPTB individuals (72 disease controls and 40 healthy controls) were involved in this study. The model was set up by 5 of 19 differentially expressed peaks (P < 0.05), m/z 4100, 4310, 6093, 8605, and 14,019. This model can discriminate patients with EPTB from non-EPTB with a sensitivity of 97.7% and a specificity of 84.1%. The test set verified that this model had good sensitivity and specificity: 94.4% and 83.6%, respectively. In conclusion, MALDI-TOF MS combined with WCX magnetic beads is a powerful technology for constructing a decision tree model and the model we built could serve as a potential diagnostic tool for EPTB.

[Diagnosis of pleural cavity extraskeletal osteosarcoma: a case report and literature review].

OBJECTIVE: To describe the manifestations and diagnosis of pleural cavity extraskeletal osteosarcoma (ESO). METHODS: One case of ESO diagnosed at the Research Institute of Tuberculosis, 309th Hospital of PLA was reported. Six cases reported in the literature were reviewed. RESULTS: Chest CT of a middle-aged man revealed an enormous heterogeneous neoplasm, about 10.9 cm x 9.2 cm x 17.7 cm in size, in the left pleural cavity. There was abundant calcification in the tumor, with signs of invasion into the diaphragm and the pleura. Pleural effusion of the left thoracic cavity was also seen on the chest CT. Osteosarcoma was confirmed by pathological study after surgical resection of the tumor. CONCLUSIONS: ESO is a rare malignant soft tissue sarcoma. Pleural cavity ESO is insidious and imaging studies often reveal a huge mass with abundant calcification. The differential diagnosis includes benign and malignant diseases of the thorax.

[Tuberculosis after organ transplantation: clinical analysis and literature review].

OBJECTIVE: To describe the clinical features, diagnosis and treatment of tuberculosis after organ transplantation. METHOD: The clinical data of 25 cases of tuberculosis after organ transplantation were retrospectively analyzed. RESULTS: Sixty-eight percent of the patients presented only mild symptoms. Fever, cough, malaise and chest tightness were among the most common manifestations. Pulmonary tuberculosis, pleurisy, miliary lesions, lymph node disease, and kidney tuberculosis were common. Involvement of two organs were present in 72% (18/25) of the patients. Radiology showed soft lesions, miliary nodules, pleural effusion, hilar and mediastinal lymphadenopathy. Bacteriology and histology were used to confirm the diagnosis in most cases. The average time from presentation to diagnosis was 38 d. The effective rate of therapy was 76% (19/25). CONCLUSION: More attention should be paid to tuberculosis after organ transplantation and immunosuppression. Prompt diagnosis and treatment are important measures to reduce the mortality.

[Clinical application and evaluation of the detection of five drugs resistance genes in Mycobacterium tuberculosis].

OBJECTIVE: To evaluate the clinical application of the detection of the drug resistant genes rPOB, katG, rPSL, PncA and embB in M. tuberculosis by using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis. METHODS: Gene mutations and anti-tuberculous drug susceptibility test were analyzed in 109 M. tuberculosis isolates by PCR-SSCP and the proportion method on Lowenstein-Jensen medium, respectively. The therapeutic effect was evaluated in patients with tuberculosis. RESULTS: Isolates from more than 50% of the patients with pulmonary tuberculosis were resistant to at least two drugs. The total rates of drug resistance to rifampin (RFP), isoniazid (INH), streptomycin (SM), pyrizinamide (PZA) and ethambutol (EB) were 80.7%, 71.5%, 78.8%, 57.7%, and 48.6%, respectively. The gene mutation rates of rpoB, katG, rpsL, pncA and embB were 76%, 68%, 71%, 51% and 30%, respectively. The gene mutations were correlated with the degree of drug-resistance to M. tuberculosis. Most of the gene mutations were found in drug-resistant isolates in high concentrations. The six month cure rates of MDR-TB, confirmed by drug susceptibility test and by PCR-SSCP, were 54.8% and 62.8%, respectively (P > 0.05). CONCLUSIONS: PCR-SSCP is a sensitive and specific method for rapid detection of rpoB, katG, rpsL, pncA and embB gene mutations in M. tuberculosis. Drug resistant gene detection may be clinically useful in the therapy of tuberculosis.