Molecular recognition of ITIM/ITSM domains with SHP2 and their allosteric effect.

Src homology 2-domain-containing tyrosine phosphatase 2 (SHP2) is a non-receptor protein tyrosine phosphatase that is widely expressed in a variety of cells and regulates the immune response of T cells through the PD-1 pathway. However, the activation mechanism and allosteric effects of SHP2 remain unclear, hindering the development of small molecule inhibitors. For the first time, in this study, the complex structure formed by the intact PD-1 tail and SHP2 was modeled. The molecular recognition and conformational changes of inactive/active SHP2 versus ITIM/ITSM were compared based on prolonged MD simulations. The relative flexibility of the two SH2 domains during MD simulations contributes to the recruitment of ITIM/ITSM and supports the subsequent conformational change of SHP2. The binding free energy calculation shows that inactive SHP2 has a higher affinity for ITIM/ITSM than active SHP2, mainly because the former's N-SH2 refers to the α-state. In addition, a significant decrease in the contribution to the binding energy of certain residues (e.g., R32, S34, K35, T42, and K55) of conformationally transformed SHP2 contributes to the above result. These detailed changes during conformational transition will provide theoretical guidance for the molecular design of subsequent novel anticancer drugs.

Response of TCE biodegradation to elevated H2 and O2: Implication for electrokinetic-enhanced bioremediation.

The study investigated the influences of pure H2 and O2 introduction, simulating gases produced from the electrokinetic-enhanced bioremediation (EK-Bio), on TCE degradation, and the dynamic changes of the indigenous microbial communities. The dissolved hydrogen (DH) and oxygen (DO) concentrations ranged from 0.2 to 0.7 mg/L and 2.6 to 6.6 mg/L, respectively. The biological analysis was conducted by 16S rRNA sequencing and functional gene analyses. The results showed that the H2 introduction enhanced TCE degradation, causing a 90.4% TCE removal in the first 4 weeks, and 131.1 µM was reduced eventually. Accordingly, cis-dichloroethylene (cis-DCE) was produced as the only product. The following three ways should be responsible for this promoted TCE degradation. Firstly, the high DH rapidly reduced the oxidation-reduction potential (ORP) value to around -500 mV, beneficial to TCE microbial dechlorination. Secondly, the high DH significantly changed the community and promoted the enrichment of TCE anaerobic dechlorinators, such as Sulfuricurvum, Sulfurospirillum, Shewanella, Geobacter, and Desulfitobacterium, and increased the abundance of dechlorination gene pceA. Thirdly, the high DH promoted preferential TCE dechlorination and subsequent sulfate reduction. However, TCE bio-remediation did not occur in a high DO environment due to the reduced aerobic function or lack of functional bacteria or co-metabolic substrate. The competitive dissolved organic carbon (DOC) consumption and unfriendly microbe-microbe interactions also interpreted the non-degradation of TCE in the high DO environment. These results provided evidence for the mechanism of EK-Bio. Providing anaerobic obligate dechlorinators, and aerobic metabolic bacteria around the electrochemical cathodes and anodes, respectively, or co-metabolic substrates to the anode can be feasible methods to promote remediation of TCE-contaminated shallow aquifer under EK-Bio technology.

Identification of novel PD-1/PD-L1 small molecule inhibitors: virtual screening, synthesis and in vitro characterisation.

The PD-1/PD-L1 pathway is considered as one of the most promising immune checkpoints in tumour immunotherapy. However, researchers are faced with the inherent limitations of antibodies, driving them to pursue PD-L1 small molecule inhibitors. Virtual screening followed by experimental validation is a proven approach to discover active compounds. In this study, we employed multistage virtual screening methods to screen multiple compound databases to predict new PD-1/PD-L1 ligands. 35 compounds were proposed by combined analysis of fitness scores, interaction pattern and MM-GBSA binding affinities. Enzymatic assay confirmed that 10 out of 35 ligands were potential PD-L1 inhibitors, with inhibitory rate higher than 50% at the concentration of 30 µM. Among them, ZDS20 was identified as the most effective inhibitor with low micromolar activity (IC50 = 3.27 µM). Altogether, ZDS20 carrying novel scaffold was identified and could serve as a lead for the development of new classes of PD-L1 inhibitors.

Preliminary results of randomized phase II study of etoposide plus lobaplatin or etoposide plus cisplatin with concurrent thoracic radiotherapy in the treatment of limited-stage small cell lung cancer.

The purpose is to compare the clinical efficacy and toxicity of etoposide plus lobaplatin (EL) or etoposide plus cisplatin (EP) with concurrent thoracic radiotherapy during the treatment of limited-stage small cell lung cancer (LS-SCLC). Forty-two patients with LS-SCLC were randomly divided into EL ( n = 19) or EP ( n = 23) regimens combined with thoracic intensity-modulated radiotherapy. The primary endpoint was 1-year progression-free survival (PFS) rate. The 1-, 2-, and 3-year PFS rates in the EL and EP cohorts were 50.8, 38.1, and 12.7%; and 56.5, 43.5, and 29.0%, respectively ( P = 0.527), whereas the 1-, 2-, and 3-year overall survival (OS) rates were 72.2, 52.5, and 43.8%; and 73.9, 48.4, and 48.4%, respectively ( P = 0.923). The hematological toxicities were similar in two cohorts. However, gastrointestinal reactions were more severe in the EP group. The incidence of nausea and vomiting in EL and EP cohorts were 31.6% vs. 73.9% ( P = 0.006) and 20.1% vs. 60.9% ( P = 0.009), respectively. The two cohorts did not show ≥grade 4 radiation esophagitis and ≥grade 3 radiation pneumonitis. The incidence of acute radiation esophagitis in EL group was lower ( P = 0.038), both groups showed a similar incidence of radiation pneumonitis ( P = 1.000). EL or EP chemotherapy with concurrent thoracic radiotherapy showed similar PFS and OS. The EL group showed milder gastrointestinal toxicity and radiation esophagitis. Radiation pneumonitis and hematological toxicity were similar in the two regimens, which can be tolerated by patients.

Study on the allosteric activation mechanism of SHP2 via elastic network models and neural relational inference molecular dynamics simulation.

As a ubiquitous protein tyrosine phosphatase, SHP2 is involved in PD-1/PD-L1 mediated tumor immune escape and undergoes substantial conformational changes. Therefore, it is considered an ideal target for tumor intervention. However, the allosteric mechanisms of SHP2 binding PD-1 intracellular ITIM/ITSM phosphopeptides remain unclear, which greatly hinders the development of novel structure-based anticancer allosteric inhibitors. In this work, the open and closed structural models of SHP2 are first constructed based on this knowledge; next their motion modes are investigated via elastic network models such as the Gaussian network model (GNM), anisotropic network model (ANM) and adaptive anisotropic network model (aANM); and finally, a possible allosteric signaling pathway is proposed using a neural relational inference molecular dynamics (NRI-MD) simulation embedded with an artificial intelligence (AI) strategy. In GNM and ANM, the N-SH2, C-SH2 and PTP domains all exhibit distinct dynamics partitions, and the N-SH2/C-SH2 regions show a rigid rotation relative to PTP. According to a series of intermediate snapshots given by aANM, N-SH2 is first identified with pY223 specifically, inducing a D'E-loop to change from ß-sheets to random coils, and then, C-SH2 serves as a fulcrum to drive N-SH2 to rotate 110° completely away from the original active sites of PTP. Finally, a possible allosteric signaling-transfer path for SHP2, namely R220-R138-T108-R32, is proposed based on NRI-MD sampling. This work provides a possible allosteric mechanism of SHP2, which is helpful for the following design of novel allosteric inhibitors and is expected to be used in clinical synergies with PD-1 monoclonal antibody.

Recombinant human endostatin combined with radiotherapy promotes cardiomyocyte apoptosis in rats via TGFß1/Smads/CTGF signaling pathway.

PURPOSE: The aim of the present study was to investigate the efficacy of recombinant human endostatin (ES) (rh-ES) combined with radiation on rat cardiomyocyte apoptosis and the regulatory mechanism of transforming growth factor beta1 (TGF-ß1)/Sma and Mad-related protein 3 (Smad3)/connective tissue growth factor (CTGF) signaling. METHOD: The primary cardiomyocytes were isolated from neonatal Sprague-Dawley rats for culture in vitro and divided into blank control group (without treatment), 10 Gy radiation + siTGF-ß1 siRNA (gene silencing) group, ES + siTGF-ß1 siRNA group, and 10 Gy radiation + ES + siTGF-ß1 siRNA group. Methyl thiazolyl tetrazolium assay was used to calculate the half-maximal inhibitory concentration (IC50) of rh-ES on cardiomyocytes. Adenoviral vector was constructed for virus packaging to silence TGF-ß1 expression in cardiomyocytes. Quantitative real-time polymerase chain reaction and Western blot were carried out to analyze TGF-ß1, Smad2, Smad3 and CTGF expression at both gene and protein levels. Flow cytometry and electron microscope were used to examine cell apoptosis. RESULTS: ES had a dose-dependent inhibitory effect on the proliferation of primary rat cardiomyocytes. ES combined with radiotherapy significantly inhibited cardiomyocyte proliferation and promoted cell apoptosis (P < 0.01). The gene and protein expression of TGF-ß1, Smad2, Smad3 and CTGF were significantly up-regulated in primary cardiomyocytes transfected with TGF-ß1 gene (P < 0.05). CONCLUSION: The combination therapy with rh-ES and radiation can promote cardiomyocyte apoptosis and aggravate myocardial cell damage via TGF-ß1/Smad3/CTGF signaling pathway.

Reovirus enhances cytotoxicity of natural killer cells against colorectal cancer via TLR3 pathway.

BACKGROUND: Cetuximab has been approved for use for first-line treatment of patients with wild-type KRAS metastatic colorectal cancer (CRC). However, treatment with cetuximab has shown limited efficacy as a CRC monotherapy. In addition, natural killer (NK) cell function is known to be severely attenuated in cancer patients. The goal of this study was to develop a new strategy to enhance antibody-dependent cell-mediated cytotoxicity (ADCC) mediated by NK cells, in combination with cetuximab against CRC cells. METHODS: Ex vivo expanded NK cells were stimulated with reovirus, and reovirus-activated NK cells mediated ADCC assay were performed on CRC cells in combination with cetuximab. The synergistic antitumor effects of reovirus-activated NK cells and cetuximab were tested on DLD-1 tumor-bearing mice. Finally, Toll-like receptor 3 (TLR3) knockdown in NK cells, along with chemical blockade of TLR3/dsRNA complex, and inhibition of the TLR3 downstream signaling pathway, were performed to explore the mechanisms by which reovirus enhances NK cell cytotoxicity. RESULTS: We first confirmed that exposure of NK cells to reovirus enhanced their cytotoxicity in a dose-dependent manner.We then investigated whether reovirus-activated NK cells exposed to cetuximab-bound CRC cells exhibited greater anti-tumor efficacy than either monotherapy. Co-culture of CRC cell lines with reovirus-activated NK cells indicated that NK cytotoxicity was significantly higher in combination with cetuximab, regardless of KRAS mutation status or EGFR expression level. We also found that reovirus activation of NK cells, in conjunction with cetuximab, resulted in significantly stronger anti-tumor efficacy.Finally, TLR3 knockdown, inhibition of TLR3/dsRNA complex or TBK1/IKKε demonstrated that activation of NK cells by reovirus was dependent on TLR3 and its downstream signaling pathway. CONCLUSIONS: This study demonstrated that combination treatment of reovirus-activated NK cells with cetuximab synergistically enhances their anti-tumor cytotoxicity, suggesting a strong candidate strategy for clinical treatment of CRC.

Pemetrexed plus cisplatin versus docetaxel plus cisplatin for stage IV lung adenocarcinoma based on propensity score matching.

The aim of this study was to compare the clinical efficacy of pemetrexed+cisplatin (PP) versus docetaxel+cisplatin (DP) for the treatment of stage IV lung adenocarcinoma. We retrospectively analyzed the clinical data of 147 patients with stage IV lung adenocarcinoma treated between January 2011 and December 2015, 100 of which were in the DP group whereas 47 were in the DP group. Main inclusion criteria were treatment-naive patients, first-line treatment with PP or DP with no molecular targeted therapy during treatment, 2-6 cycles of first-line chemotherapy with unknown status of epidermal growth factor receptor (EGFR) mutation, 18-75 years of age, and Karnofsky performance status score of at least 70. Prognostic factors for survival were identified by using univariate and multivariate analyses. Propensity score matching was performed to further adjust for confounding. A total of 47 pairs were successfully matched between the two groups. The median overall survival was 9.0 months in the DP group and 17.0 months in the PP group; the 1-year survival rate was 29.8 and 59.6%, respectively; the 2-year survival rate was 12.8 and 21.1%, respectively (χ=4.128, P=0.042); and median progression-free survival was 6.0 and 8.0 months, respectively (χ=4.839, P=0.028). Cox multivariate analysis showed that chemotherapy regimen and number of metastatic organs were independent factors for OS. The effect of the radiotherapy dose on the primary tumor on OS was close to statistically significant. The incidence of grade 3-4 neutropenia was more significantly reduced in the DP group than in the PP group after matching (61.7 vs. 27.7%, P=0.002), with no between-group difference for adverse effects on platelets or hemoglobin. For patients with stage IV lung adenocarcinoma and unknown EGFR mutation status, PP was more effective than DP in prolonging survival and had a less adverse effect on neutrophils.

Integrating mean and variance heterogeneities to identify differentially expressed genes.

BACKGROUND: In functional genomics studies, tests on mean heterogeneity have been widely employed to identify differentially expressed genes with distinct mean expression levels under different experimental conditions. Variance heterogeneity (aka, the difference between condition-specific variances) of gene expression levels is simply neglected or calibrated for as an impediment. The mean heterogeneity in the expression level of a gene reflects one aspect of its distribution alteration; and variance heterogeneity induced by condition change may reflect another aspect. Change in condition may alter both mean and some higher-order characteristics of the distributions of expression levels of susceptible genes. RESULTS: In this report, we put forth a conception of mean-variance differentially expressed (MVDE) genes, whose expression means and variances are sensitive to the change in experimental condition. We mathematically proved the null independence of existent mean heterogeneity tests and variance heterogeneity tests. Based on the independence, we proposed an integrative mean-variance test (IMVT) to combine gene-wise mean heterogeneity and variance heterogeneity induced by condition change. The IMVT outperformed its competitors under comprehensive simulations of normality and Laplace settings. For moderate samples, the IMVT well controlled type I error rates, and so did existent mean heterogeneity test (i.e., the Welch t test (WT), the moderated Welch t test (MWT)) and the procedure of separate tests on mean and variance heterogeneities (SMVT), but the likelihood ratio test (LRT) severely inflated type I error rates. In presence of variance heterogeneity, the IMVT appeared noticeably more powerful than all the valid mean heterogeneity tests. Application to the gene profiles of peripheral circulating B raised solid evidence of informative variance heterogeneity. After adjusting for background data structure, the IMVT replicated previous discoveries and identified novel experiment-wide significant MVDE genes. CONCLUSIONS: Our results indicate tremendous potential gain of integrating informative variance heterogeneity after adjusting for global confounders and background data structure. The proposed informative integration test better summarizes the impacts of condition change on expression distributions of susceptible genes than do the existent competitors. Therefore, particular attention should be paid to explicitly exploit the variance heterogeneity induced by condition change in functional genomics analysis.

Might radiation therapy in addition to chemotherapy improve overall survival of patients with non-oligometastatic Stage IV non-small cell lung cancer?: Secondary analysis of two prospective studies.

BACKGROUND: The role of radiation therapy in addition to chemotherapy has not been well established in non-oligometastatic Stage IV non-small cell lung cancer (NSCLC). We aimed to investigate overall survival (OS) of non-oligometastatic Stage IV NSCLC treated with chemotherapy with concurrent radiation to the primary tumor. METHODS: Eligible patients were screened from two prospective studies. Oligometastatic and non-oligometastatic NSCLC were defined as having < 5 and ≥5 metastatic lesions, respectively. Prognostic factors for OS were identified by using univariate and multivariate analysis. Landmark analysis and propensity-score matching (PSM) were each performed to further adjust for confounding. RESULTS: A total of 274 patients were identified as the study cohort: 183 had non-oligometastatic disease. For all 274 patients, those who received a radiation dose ≥63 Gy to the primary tumor and had oligometastatic disease had better OS (P < 0.001 and P = 0.017, respectively). When patients were subdivided into those with oligometastatic or non-oligometastatic disease, a radiation dose ≥ 63 Gy remained a significant prognostic factor for better OS. For non-oligometastatic patients, multivariate analysis showed that receiving ≥63 Gy radiation, having a GTV <146 cm3, having response to chemotherapy, and having stable or increased post-treatment KPS independently predicted better OS (P = 0.018, P = 0.014, P = 0.014, and P = 0.001). After PSM in non-oligometastatic patients, a higher radiation dose (≥63 Gy) remained to be correlated with better OS. By landmark analysis, aggressive radiation (≥63 Gy) remained to be correlated with better OS in Pre-PSM cohort (P = 0.005) and Post-PSM cohort (P = 0.004). CONCLUSIONS: Radiation dose, primary tumor volume, response to chemotherapy and KPS after treatment are associated with OS in patients with non-oligometastatic disease; on basis of effective system chemotherapy, aggressive thoracic radiotherapy may prolong OS.

A Generalized Sequential Bonferroni Procedure for GWAS in Admixed Populations Incorporating Admixture Mapping Information into Association Tests.

OBJECTIVE: To develop effective methods for GWAS in admixed populations such as African Americans. METHODS: We show that, when testing the null hypothesis that the test SNP is not in background linkage disequilibrium with the causal variants, several existing methods cannot control well the family-wise error rate (FWER) in the strong sense in GWAS. These existing methods include association tests adjusting for global ancestry and joint association tests that combine statistics from admixture mapping tests and association tests that correct for local ancestry. Furthermore, we describe a generalized sequential Bonferroni (smooth-GSB) procedure for GWAS that incorporates smoothed weights calculated from admixture mapping tests into association tests that correct for local ancestry. We have applied the smooth-GSB procedure to analyses of GWAS data on American Africans from the Atherosclerosis Risk in Communities (ARIC) Study. RESULTS: Our simulation studies indicate that the smooth-GSB procedure not only control the FWER, but also improves statistical power compared with association tests correcting for local ancestry. CONCLUSION: The smooth-GSB procedure can result in a better performance than several existing methods for GWAS in admixed populations.

Radiation dose and survival of patients with stage IV non-small cell lung cancer undergoing concurrent chemotherapy and thoracic three-dimensional radiotherapy: reanalysis of the findings of a single-center prospective study.

BACKGROUND: The objective of this study was to evaluate the radiation dose and response in terms of local-regional progression-free survival (LRPFS) and overall survival (OS) of patients with stage IV non-small cell lung cancer (NSCLC) undergoing concurrent chemotherapy and thoracic three-dimensional radiotherapy. METHODS: In all, we enrolled 201 patients with stage IV NSCLC in this study and analyzed OS in 159 patients and LRPFS in 120. RESULTS: The 1-, 2-, 3-, and 5-year OS rates were 46.2%, 19.5%, 11.7%, and 5.8%, respectively, the median survival time being 12 months. The median survival times in differential treatment response of primary tumors were 19 of complete response, 13 of partial response, 8 of stable disease, and 6 months of progressive disease, respectively (P = 0.000). The 1-, 2-, 3-, and 5-year LRPFS rates of patients undergoing four to five cycles with doses ≥63 Gy and <63 Gy were 77.4% and 32.6%, 36.2% and 21.7%, 27.2% and 0, and 15.9% and 0, respectively (P = 0.002). According to multivariate analyses, four to five cycles of chemotherapy, gross tumor volume <175.00 cm3 and post-treatment Karnofsky Performance Status score stable or increased by at least 10 units were independent prognostic factors for better OS (P = 0.035, P = 0.008, and P = 0.000, respectively). Radiation dose to the primary tumor ≥63 Gy resulted in better OS (P = 0.057) and LRPFS (P = 0.051), both findings being of borderline significance. CONCLUSIONS: Treatment of IV NSCLC with joint administration of four to five cycles of chemotherapy and three-dimensional radiotherapy may prolong survival, particularly in patients receiving ≥63 Gy radiotherapy, with gross tumor volume <175.00 cm3 and post-treatment Karnofsky Performance Status score not lower than pretreatment values.

Rational design of molecularly imprinted electrochemical sensor based on Nb2C-MWCNTs heterostructures for highly sensitive and selective detection of Ochratoxin a.

Developing an efficient method for screening Ochratoxin A (OTA) in agriculture products is vital to ensure food safety and human health. However, the complex food matrix seriously affects the sensitivity and accuracy. To address this issue, we designed a novel molecularly imprinted polymer (MIP) electrochemical sensor based on multiwalled carbon nanotube-modified niobium carbide (Nb2C-MWCNTs) with the aid of the density functional theory (DFT). In this design, a glassy carbon electrode (GCE) was first modified by Nb2C-MWCNTs heterostructure. Afterward, the MIP layer was prepared, with ortho-toluidine as a functional monomer selected via DFT and OTA acting as a template on the surface of Nb2C-MWCNTs/GCE using in-situ electropolymerization. Electrochemical tests and physical characterization revealed that Nb2C-MWCNTs improved the sensor's active surface area and electron transmission capacity. Nb2C-MWCNTs had a good synergistic effect on MIP, endowing the sensor with high sensitivity and specific recognition of OTA in complex food matrix systems. The MIP sensor showed a wide linear range from 0.04 to 10.0 µM with a limit of detection (LOD) of 3.6 nM. Moreover, it presented good repeatability and stability for its highly antifouling effect on OTA. In real sample analysis, the recoveries, ranging from 89.77% to 103.70%, agreed well with the results obtained by HPLC methods, suggesting the sensor has good accuracy and high potential in practical applications.

PD-1 Inhibitor Aggravate Irradiation-Induced Myocardial Fibrosis by Regulating TGF-ß1/Smads Signaling Pathway via GSDMD-Mediated Pyroptosis.

Cancer therapy has entered a new era with the use of programmed cell death protein 1 (PD-1) immune checkpoint inhibitors. When combined with thoracic radiotherapy, it demonstrates synergistic anti-tumor effects and potentially worsens radiation-induced myocardial fibrosis (RIMF). RIMF is the final stage of radiation-induced heart disease (RIHD) and a potentially fatal clinical complication of chest radiotherapy. It is characterized by decreased ventricular elasticity and distensibility, which can result in decreased ejection fraction, heart failure, and even sudden cardiac death. Pyroptosis, a type of programmed cell death, is mediated by members of the gasdermin (GSDM) family and has been associated with numerous cardiac disorders. The effect of pyroptosis on myocardial fibrosis caused by a combination of radiotherapy and PD-1 inhibitors remains uncertain. In this study, a 6MV X-ray of 20 Gy for local heart irradiation was used in the RIHD mouse model. We noticed that PD-1 inhibitors aggravated radiation-induced cardiac dysfunction and RIMF, concurrently enhancing the presence of CD8+ T lymphocytes in the cardiac tissue. Additionally, our findings indicated that the combination of PD-1 inhibitor and thoracic radiation can stimulate caspase-1 to cleave GSDMD, thereby regulating pyroptosis and liberating interleukin-8 (IL-18). In the myocardium of mice, the manifestation of pyroptosis mediated by GSDMD is accompanied by the buildup of proteins associated with fibrosis, such as collagen I, transforming growth factor ß1 (TGF-ß1), interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), and tumor necrosis factor α (TNF-α). Moreover, it was discovered that TFG-ß1 induced the phosphorylation of Smad2/Smad3 when the cardiac underwent PD-1 inhibitor in conjunction with thoracic irradiation (IR). The findings of this research indicate that PD-1 inhibitor worsen RIMF in mice by triggering GSDMD-induced pyroptosis and influencing the TGF-ß1/Smads pathway. While using the caspase-1 inhibitor Z-YVAD-FMK, RIMF can be alleviated. Blocking GSDMD may be a viable strategy for managing myocardial fibrosis caused by the combination of PD-1 inhibitors and radiotherapy.

Coxsackie B virus-induced myocarditis in a patient with a history of lymphoma: A case report and review of literature.

INTRODUCTION: In rare occasions, coxsackievirus infections can cause serious illness, such as encephalitis and myocarditis. The immunotherapies of cancer could increase the risk of myocarditis, especially when applying immune checkpoint inhibitors. Herein, we report a rare case of Coxsackie B virus-induced myocarditis in a patient with a history of lymphoma. CASE PRESENTATION: A 32-year-old woman was admitted to the hospital with recurrent fever for more than 20 days, and she had a history of lymphoma. Before admission, the positron emission tomography/computed tomography result indicated that the patient had no tumor progression, and she was not considered the cancer-related fever upon arriving at our hospital. Patient's red blood cell, platelet count, and blood pressure were decreased. In addition, she had sinus bradycardia and 3 branch blocks, which was consistent with acute high lateral and anterior wall myocardial infarction. During hospitalization, the patient had recurrent arrhythmia, repeated sweating, poor mentation, dyspnea, and Coxsackie B virus were detected in patient's blood samples by pathogen-targeted next-generation sequencing. The creatine kinase, creatine kinase MB, and N-terminal pro-brain natriuretic peptide were persistently elevated. Consequently, the patient was diagnosed with viral myocarditis induced by Coxsackie B virus, and treated with acyclovir, gamma globulin combined with methylprednisolone shock therapy, trimetazidine, levosimendan, sildenan, continuous pump pressors with m-hydroxylamine, entecavir, adefovir, glutathione, pantoprazole, and low-molecular-weight heparin. Her symptoms worsened and died. CONCLUSION: We reported a case with a history of lymphoma presented with fever, myocardial injury, who was ultimately diagnosed with Coxsackie B virus-induced myocarditis. Moreover, pathogen-targeted next-generation sequencing indeed exhibited higher sensitivity compared to mNGS in detecting Coxsackie B virus.

S288T mutation altering MmpL3 periplasmic domain channel and H-bond network: a novel dual drug resistance mechanism.

CONTEXT: Mycobacterial membrane proteins Large 3 (MmpL3) is responsible for the transport of mycobacterial acids out of cell membrane to form cell wall, which is essential for the survival of Mycobacterium tuberculosis (Mtb) and has become a potent anti-tuberculosis target. SQ109 is an ethambutol (EMB) analogue, as a novel anti-tuberculosis drug, can effectively inhibit MmpL3, and has completed phase 2b-3 clinical trials. Drug resistance has always been the bottleneck problem in clinical treatment of tuberculosis. The S288T mutant of MmpL3 shows significant resistance to the inhibitor SQ109, while the specific action mechanism remains unclear. The results show that MmpL3 S288T mutation causes local conformational change with little effect on the global structure. With MmpL3 bound by SQ109 inhibitor, the distance between D710 and R715 increases resulting in H-bond destruction, but their interactions and proton transfer function are still restored. In addition, the rotation of Y44 in the S288T mutant leads to an obvious bend in the periplasmic domain channel and an increased number of contact residues, reducing substrate transport efficiency. This work not only provides a possible dual drug resistance mechanism of MmpL3 S288T mutant but also aids the development of novel anti-tuberculosis inhibitors. METHODS: In this work, molecular dynamics (MD) and quantum mechanics (QM) simulations both were performed to compare inhibitor (i.e., SQ109) recognition, motion characteristics, and H-bond energy change of MmpL3 after S288T mutation. In addition, the WT_SQ109 complex structure was obtained by molecular docking program (Autodock 4.2); Molecular Mechanics/ Poisson Boltzmann Surface Area (MM-PBSA) and Solvated Interaction Energy (SIE) methods were used to calculate the binding free energies (∆Gbind); Geometric criteria were used to analyze the changes of hydrogen bond networks.

Overall survival and toxicities regarding thoracic three-dimensional radiotherapy with concurrent chemotherapy for stage IV non-small cell lung cancer: results of a prospective single-center study.

BACKGROUND: The role of chemotherapy given concurrently with thoracic three-dimensional radiotherapy for stage IV non-small cell lung cancer (NSCLC) is not well defined. We performed this study to investigate overall survival and toxicity in patients with stage IV NSCLC treated with this modality. METHODS: From 2003 to 2010, 201 patients were enrolled in this study. All patients received chemotherapy with concurrent thoracic three-dimensional radiotherapy. The study endpoints were the assessment of overall survival (OS) and acute toxicity. RESULTS: For all patients, the median survival time (MST) was 10.0 months, and the 1-, 2- and 3-year OS rates were 40.2%, 16.4%, and 9.6%, respectively. The MST was 14.0 months for patients who received a total radiation dose ≥63 Gy to the primary tumor, whereas it was 8.0 months for patients who received a total dose <63 Gy (P = 0.000). On multivariate analysis, a total dose ≥63 Gy, a single site of metastatic disease, and undergoing ≥4 cycles of chemotherapy were independent prognostic factors for better OS (P = 0.007, P = 0.014, and P = 0.038, respectively); radiotherapy involving metastatic sites was a marginally significant prognostic factor (P = 0.063). When the whole group was subdivided into patients with metastasis at a single site and multiple sites, a higher radiation dose to the primary tumor remained a significant prognostic factor for improved OS. For patients who received ≥4 cycles of chemotherapy, high radiation dose remained of benefit for OS (P = 0.001). Moreover, for the subgroup that received <4 chemotherapy cycles, the radiation dose was of marginal statistical significance regarding OS (P = 0.063). Treatment-related toxicity was found to be acceptable. CONCLUSIONS: Radiation dose to primary tumor, the number of metastatic sites, and the number of chemotherapy cycles were independent prognostic factors for OS in stage IV NSCLC patients treated with concurrent chemoradiotherapy. In addition to systemic chemotherapy, aggressive thoracic radiotherapy was shown to play an important role in improving OS. TRIAL REGISTRATION: Registered on (ChiCTR-TNC-10001026).

The response of C/N/S cycling functional microbial communities to redox conditions in shallow aquifers using in-situ sediment as bio-trap matrix.

Microbial communities are fundamental components driving critical biogeochemical carbon (C), nitrogen (N) and sulfur (S) cycles in groundwater ecosystems. The reduction-oxidation (redox) potential is one important environmental factor influencing the microbial community composition. Here, we developed a bio-trap method using in-situ sediment as a matrix to collect aquifer sediment samples and evaluate the response of microbial composition and C/N/S cycling functions to redox variations created by providing sole O2, joint O2 and H2, and sole H2 to three wells. Illumina sequencing analyses showed that the microbial communities in the bio-trap sediment could respond quickly to redox changes in the wells, demonstrating that this bio-trap method is promising for detecting microbial variation in the aquifer sediment. The microbial metabolic functions related to C, N and S cyclings and organic pollutants degradation were predicted by the Kyoto Encyclopedia of Genes and Genomes (KEGG) approach. It was found that the joint O2 and H2 injection produced medium oxidation-reduction potential (ORP -346 and -614 mV) and enhanced more microbial functions than sole O2 or H2, which mainly include oxidative phosphorylation, most carbon source metabolism, various pollutants degradation, and nitrogen and sulfur metabolism. Moreover, the functional genes encoding phenol monooxygenase, dioxygenase, nitrogen fixation, nitrification, aerobic and anaerobic nitrate reductase, nitrite reductase, nitric oxide reductase, and sulfur oxidation increased. These findings tell us the contaminant bioremediation and N, S metabolism can be promoted by adjusting ORP realised by injecting joint O2 and H2.

Identification and synergetic mechanism of TCE, H2 and O2 metabolic microorganisms in the joint H2/O2 system.

The sole H2 and O2 usually promote chlorinated hydrocarbons (CHCs) biotransformation by several mechanisms, including reductive dechlorination and aerobic oxidation. However, the mechanism of the CHCs transformation in joint H2 and O2 system (H2/O2 system) is still unclear. In this study, the degradation kinetics of trichloroethene (TCE) were investigated and DNA stable isotope probing (DNA-SIP) were used to explore the synergistic mechanism of functional microorganisms on TCE degradation under the condition of H2/O2 coexistence. In the H2/O2 microcosm, TCE was significantly removed by 13.00 µM within 40 days, much higher than N2, H2 and O2 microcosms, and 1,1-DCE was detected as an intermediate. DNA-SIP technology identified three anaerobic TCE metabolizers, five aerobic TCE metabolizers, nine hydrogen-oxidizing bacteria (HOB), some TCE metabolizers utilizing limited O2, and some anaerobic dechlorinating bacteria reductively using H2 to dechlorinate TCE. It is also confirmed for the first time that 3 OUTs belonging to Methyloversatilis and SH-PL14 can simultaneously utilize H2 and O2 as energy sources to grow and metabolize TCE or 1,1-DCE. HOB may provide carbon sources or electron acceptors or donors for TCE biotransformation. These findings confirm the coexistence of anaerobic and aerobic TCE metabolizers and degraders, which synergistically promoted the conversion of TCE in the joint H2/O2 system. Our results provide more information about the functional microbe resources and synergetic mechanisms for TCE degradation.

A novel strategy for arsenic removal from acid wastewater via strong reduction processing.

Due to the high-acidic arsenic-containing wastewater pollution greatly threatening human health and ecological safety, a simple and efficient method for reducing arsenic was proposed in this paper to solve this problem. By using potassium borohydride (KBH4) as a reducing agent, the soluble arsenic was converted into the gaseous arsine (AsH3) or solid arsenic (As0) to achieve the purpose of removing arsenic in wastewater. By exploring the reaction kinetics of the arsenic removal process, it was found that the fast reaction stage (0-2 min) conformed to pseudo-first-order kinetics. The removal rate of arsenic increased to over 73% in 0.5 min, and reaction equilibrium was reached after 30 min. Various influence factors including arsenic valence, aeration, addition method, concentrations of reducing agent, and hydrogen ion (H+) were investigated. The results showed that As(III) was easier to be removed by reduction than As(V), while adding KBH4 in multiples and aeration were both favorable to the removal of arsenic. Increased concentration of KBH4 also enhanced the removal of arsenic. Appropriate H+ concentration contributed to the arsenic removal, but excessive H+ concentration conversely has an inhibitory effect. The maximum removal rate of arsenic was 95.87%, with the maximum removal capacity of 45.50 mg/g. Based on the XRD and SEM-EDS analysis of residue, amorphous arsenic (As0) with a mass ratio of more than 94.52% was generated after the reduction of soluble arsenic. Our study demonstrated that the reaction mechanism of reductive degradation is soluble arsenic with hydrogen radicals (H•) to form arsenic (As0) and arsine (AsH3) (in the molar ratio of 6:1). Although the generated solid arsenic (As0) is convenient for the soluble arsenic removal from wastewater, attention must be paid to the formation of AsH3, and strategies for AsH3 treatment should be considered.