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Yu Y, Han C, Gan X, Tian W, Zhou C, Zhou Y, Xu X, Wen Z, Liu W. Predictive value of spectral computed tomography parameters for EGFR gene mutation in non-small-cell lung cancer. Clin Radiol 2024:S0009-9260(24)00238-1. [PMID: 38797609 DOI: 10.1016/j.crad.2024.04.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 03/25/2024] [Accepted: 04/27/2024] [Indexed: 05/29/2024]
Abstract
AIM To explore the predictive value of morphological signs and quantitative parameters from spectral CT for EGFR gene mutations in intermediate and advanced non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS This retrospective observational study included patients with intermediate or advanced NSCLC at Xinjiang Medical University Affiliated Tumor Hospital between January 2017 and December 2019. The patients were divided into the EGFR gene mutation-positive and -negative groups. RESULTS Seventy-nine patients aged 60.75 ± 9.66 years old were included: 32 were EGFR mutation-positive, and 47 were negative. There were significant differences in pathological stage (P<0.001), tumor diameter (P=0.019), lobulation sign, intrapulmonary metastasis, mediastinal lymph node metastasis, distant metastasis (P<0.001), bone metastasis (P<0.001), arterial phase normalized iodine concentration (NIC) (P=0.001), venous phase NIC (P=0.001), slope of the energy spectrum curve (λ) (P<0.001), and CT value at 70 keV in arterial phase (P=0.004) and venous phase (P=0.003) between the EGFR mutation-positive and -negative patients. The multivariable logistic regression analysis showed that intrapulmonary metastasis, distant metastasis, venous phase NIC, venous phase λ, and pathological stage were independent factors predicting EGFR gene mutations, with high diagnostic power (AUC = 0.975, 91.5% sensitivity, and 90.6% specificity). CONCLUSION The pathological stage and the spectral CT parameters of intrapulmonary metastasis, distant metastasis, venous phase NIC, and venous phase λ might pre-operatively predict EGFR gene mutations in intermediate and advanced NSCLC.
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Liang JY, Wang YM, Wen Z, Zhang WH, Gao ZZ, Wang Z, Guo SP. [Clinicopathological characteristics and immune microenvironment of breast squamous cell carcinoma]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2024; 53:337-343. [PMID: 38556816 DOI: 10.3760/cma.j.cn112151-20231023-00293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/02/2024]
Abstract
Objective: To investigate the clinicopathological characteristics of breast squamous cell carcinoma and to analyze the relationship between its immune microenvironment tumor infiltrating lymphocytes (TILs) and prognosis. Methods: Forty-four cases of primary squamous cell carcinoma of the breast diagnosed and treated in the First Affiliated Hospital of Air Force Medical University, Xi'an, China from January 2006 to July 2022 were selected. Their clinicopathological characteristics were analyzed. The cell composition of TILs was evaluated using immunohistochemistry (Mainly markers of B lymphocytes, T lymphocytes and plasma cells). The relationship between TILs and prognosis was also analyzed. Results: The 44 patients of breast squamous cell carcinoma were all female and all were invasive carcinoma. Eight cases (8/44, 18.2%) were squamous cell carcinoma, while 36 cases (36/44, 81.8%) were mixed squamous cell carcinoma. The mixed components included non-specific carcinoma and spindle cell metaplastic carcinoma (17 cases each). One case contained ductal carcinoma in situ of the breast and 1 case contained tubular carcinoma. The proportion of squamous cell carcinoma was 10% to 90%. The cases with pure squamous cell carcinoma often had a large cystic cavity, which was lined by atypical squamous epithelium, while infiltrating squamous cell carcinoma nests were seen in the breast tissue around the cystic cavity. Immunohistochemical staining showed that p63 and CK5/6 were expressed in the squamous cell carcinoma component, but ER, PR and HER2 were not, except for one case of HER2 1+. The positive rates of TRPS1 and PDL-1 were 76% and less than 1%, respectively. Fifteen cases were in the high TILs group (TILs≥30%) and 29 cases were in the low TILs group (TILs<30%). Twenty-three patients were followed up for 5 to 118 months. Among them, 12 died within 3 years and 9 were alive at the end of the follow up. There was no significant difference in TNM stage, TILs and prognosis between simple squamous cell carcinoma and mixed squamous cell carcinoma. Conclusions: Breast squamous cell carcinoma can be divided into simple squamous cell carcinoma and mixed squamous cell carcinoma. There are differences in gross findings and histology between the simple and mixed squamous cell carcinoma of the breast. Sufficient samples should be taken to avoid missing the diagnosis of a minor squamous component. The prognosis of patients with high TILs is significantly better than that of patients with low TILs. The expression rate of TRPS1 in primary squamous cell carcinoma of breast is high and helpful to the differential diagnosis from metastatic squamous cell carcinoma.
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Peng L, Wen S, Yan J, Yu H, Wen Z, Wang Z. Inhibition Effect of Triphenylmethane Dyes for the Corrosion of Carbon Steel in CO 2-Saturated NaCl Corrosion Medium. MATERIALS (BASEL, SWITZERLAND) 2024; 17:1094. [PMID: 38473566 DOI: 10.3390/ma17051094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 01/16/2024] [Accepted: 01/17/2024] [Indexed: 03/14/2024]
Abstract
Carbon dioxide corrosion presents a significant challenge in the oil and gas field. This study simulates the corrosive environment characteristics of oil and gas fields to investigate the corrosion inhibition properties of three triphenylmethane dyes. The inhibitive performance and mechanisms of these dyes were analyzed through weight loss and electrochemical testing, revealing that crystal violet (CV) exhibited a superior inhibition effectiveness over malachite green (MG) and Fuchsine basic (FB). At a concentration of 150 ppm in a CO2-saturated 5% NaCl solution at 25 °C, CV achieved an impressive maximum inhibition efficiency of 94.89%. With the increase in temperature, the corrosion rate slightly decreased, and the corrosion rate was 92.94% at 60 °C. The investigated CV acted as a mixed-type corrosion inhibitor and its protection obeyed the Langmuir adsorption isotherm. The corrosion morphology was characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and confocal laser scanning microscopy (CLMS). Quantum chemical calculations and molecular dynamics simulations were employed to validate the corrosion inhibition mechanisms, providing guidance for the further application of these dyes in corrosion control.
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Wen Z, Zhang WH, Liang JY, Chai J, Wang YM, Xu WN, Wang Z, Fan LN. [Clinicopathological and molecular genetic characteristics of ELOC mutated renal cell carcinoma]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2023; 52:1204-1209. [PMID: 38058035 DOI: 10.3760/cma.j.cn112151-20230915-00178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
Objective: To investigate the clinicopathological features, molecular genetic features, differential diagnosis and prognosis of ELOC mutated renal cell carcinoma. Methods: From January 2015 to June 2022, 11 cases of renal cell carcinoma with clear-cell morphology, expression of CAⅨ and CK7 and no 3p deletion were collected. Two cases of ELOC mutant renal cell carcinoma were diagnosed using whole exome sequencing (WES). The clinical features, morphology, immunophenotype, FISH and WES results were analyzed. The relevant literature was reviewed. Results: The two patients were both male, aged 29 and 51 years, respectively. They were both found to have a renal mass by physical examination. The maximum diameters of the tumors were 3.5 cm and 2.0 cm, respectively. At the low magnification, the tumors were well-defined. The tumor cells showed a pushing border and were separated by thick fibrous bands, forming nodules. The tumor cells were arranged in a variety of patterns, including tubular, papillary, solid nest or alveolar. At high magnification, the tumor cells were large, with well-defined cell borders and clear cytoplasm or fine eosinophilic granules. CAⅨ was diffusely box-like positive in both cases. Case 1 was partially and moderately positive for CK7, strongly positive for CD10, diffusely and moderately positive for P504S, and weakly positive for 34βE12. In case 2, CK7 and CD10 were both partially, moderately positive and P504s were diffusely positive, but 34βE12 was negative. FISH results showed that both cases had no 3p deletion. ELOC c.235T>A (p.Y79N) mutation was identified using WES in case 1, while ELOC c.236_237inv (p.Y79C) mutation was identified in case 2. Conclusions: As a new clinical entity, ELOC mutated renal cell carcinoma may be underdiagnosed due to its overlap with clear cell renal cell carcinoma in morphology and immunophenotype. The diagnosis of renal cell carcinoma with ELOC mutation should be confirmed by morphology, immunohistochemistry, FISH and gene mutation detection. However, more additional cases are needed to explain its biological behavior and prognosis.
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Zhu J, Qu Y, Lu M, Ma A, Mo J, Wen Z. CT-based radiomics for prediction of pulmonary haemorrhage after percutaneous CT-guided transthoracic lung biopsy of pulmonary nodules. Clin Radiol 2023; 78:e993-e1000. [PMID: 37726191 DOI: 10.1016/j.crad.2023.08.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 08/14/2023] [Accepted: 08/23/2023] [Indexed: 09/21/2023]
Abstract
AIM To evaluate the feasibility of intranodular and perinodular computed tomography (CT) radiomics features for predicting the occurrence of pulmonary haemorrhage after percutaneous CT-guided transthoracic lung biopsy (PCTLB) in pulmonary nodules. MATERIALS AND METHODS The data for 332 patients with pulmonary nodules who underwent PCTLB were reviewed retrospectively. Pulmonary haemorrhage after PCTLB was evaluated using CT (144 cases occurred). Radiomics features based on gross nodular (GNV) and perinodular volumes (PNV) were extracted from pre-biopsy CT images and features selection using least absolute shrinkage and selection operator (LASSO) regression, and three radiomics scores (rad-scores) were built. Rad-scores, clinical, and clinical-radiomic models were developed and evaluated to predict the occurrence of pulmonary haemorrhage. RESULTS Five, five, and six significant features were selected for prediction of pulmonary haemorrhage based on GNV, PNV, and GNV + PNV, respectively. Lesion depth was the only clinical characteristics related to pulmonary haemorrhage. Lesion depth and rad-score based on GNV, PNV, and GNV + PNV for predicting the pulmonary haemorrhage achieved areas under the curves (AUCs) of 0.656, 0.645, 0.651, and 0.635 in the validation group, respectively. Three clinical-radiomic models improved the AUCs to 0.743, 0.723, and 0.748. The performance of rad-score_GNV + PNV combined with lesion depth outperformed the clinical model (p=0.024) and the radiomics signature (p=0.038). In addition, the radiomics signatures were significantly associated with higher-grade pulmonary haemorrhage (p<0.05). CONCLUSIONS Radiomics features from intranodular and perinodular regions of pulmonary nodules have good predictive ability for pulmonary haemorrhage after PCTLB, which may provide additional predictive value for clinical practice.
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Wang H, Zhang X, Yang J, Wen Z, Rhee DJ, Sims C, Alsanea F, Lee A, Hunter R, Williamson T, Gunn GB, Frank SJ, Phan J. Proton Based Stereotactic Radiotherapy for Skull Base Patients: Dosimetric Comparison to 4 Modern Radiation Treatment Modalities. Int J Radiat Oncol Biol Phys 2023; 117:e733-e734. [PMID: 37786132 DOI: 10.1016/j.ijrobp.2023.06.2257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Re-irradiation with ablative doses to a smaller target volume and strict critical structure constraint is a challenge for modern radiation planning and delivery systems. Several advanced radiation treatment techniques can be used for fractionated stereotactic ablative radiosurgery (FSRS) in select patients with unresectable recurrent head and neck tumors. In this study, in order to better understand the dosimetry advantage of each technique, we compare the stereotactic treatment plans of our new small spot size Hitachi proton treatment unit to those of CyberKnife stereotactic radiosurgery (CK), Gamma Knife radiosurgery (GK), volumetric modulated arc therapy (VMAT), and MR Linac radiotherapy (MRL). MATERIALS/METHODS Ten FSRS skull base patients treated at our institution using VMAT (n = 5) or GK (n = 5) techniques. Intensity-modulated proton therapy (IMPT) plans were created in Raystation using Monte Carlo dose calculation algorithm. VMAT, CK, GK and MRL plans were generated in RayStation, Accuray Precision, Leksell Gamma Plan, and Monaco treatment planning systems, separately. Planning goals were to achieve the best target coverage of prescribed dose without compromising the critical organs at risk dose volume constraints of the clinical treatment plans. Plans were compared based on percent CTV coverage, Paddick conformity index (PCI), gradient index (GI, V50/V100), dose homogeneity index (HI, (D2-D98)/D50), low dose bath volume (LDBV, ratio of total volume irradiated between 20% and 50% prescription dose and the target volume), beam-on-time (BOT), and mean/maximum doses to brainstems. RESULTS The median target volume was 15.5 cm3 (range 1.0 - 36.23 cm3). The prescription was 45 Gy in 5 fractions for VMAT patients, and 21 - 27 Gy in 3 fractions for GK patients. The comparison of the treatment plans of these 5 delivery modalities was shown in table. All techniques achieved comparable CTV coverage. GI was superior for GK plans and outstanding in CK and IMPT plans. IMPT plans were also outstanding in regard to BOT and PCI. Significantly improved HI, LDBV and brainstem mean doses were achieved in IMPT plans. For adjacent brainstem and other OARs, maximum doses were comparable among all techniques. CONCLUSION In these five advanced radiation therapy modalities, proton therapy SBRT showed dosimetric advantage over other modalities to spare nearby OARs without sacrifice of target coverage. Further studies are needed to utilize this clinical benefit and investigate plan robustness.
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Pham D, Wang JY, Kidd EA, Wen Z, Smith LM, Lyu Q, Boudet J, Bessieres I, Hristov DH. Fixed-Field IMRT for Cervix Carcinoma Patients on an MR-LINAC Platform: Dosimetric Feasibility and Challenges. Int J Radiat Oncol Biol Phys 2023; 117:e538. [PMID: 37785663 DOI: 10.1016/j.ijrobp.2023.06.1828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) To investigate the impact of MR-LINAC performance characteristics and inverse planning implementation on the feasibility of fixed-field IMRT for cervix carcinoma patients by benchmarking MR-LINAC plans against clinically used VMAT plans in a single institution study and multi-institutional treatment planning challenge. MATERIALS/METHODS For 10 cervix cancer patients who had previously received Linac-based VMAT, new treatment plans were optimized for MR-LINAC IMRT using 6X FFF fixed fields with maximum available field size of 27.4 x 24.1 cm2. Dose optimization was performed on the clinically used planning CT and structure set. Prescribed dose was 48.6 Gy in 27 fractions for all patients with 6 patients receiving an additional integrated boost for a total of 58.05 Gy to involved nodes. Constraints were based on our institutional protocol as per Table 1. IMRT delivery time was limited to 20 min. Original clinically used VMAT plans were generated on Eclipse (Varian Medical System) using 3 to 4 arcs. For the multi-institutional planning challenge, the data set from a single patient was anonymized and shared to participants. Participants used a single MR-based Linac planning platform to generate a plan based on our institutional constraints, with maximum treatment time limited to 20 min. For all analyses, a paired samples t-test was used to compare the significance defined at p < 0.05. RESULTS For MR-LINAC plans, the mean number of fields used was 23, mean number of segments 229, and the average estimated treatment delivery time was 17.3 minutes. MR-LINAC plans showed a significantly higher heterogeneity and dose to organs at risk compared to VMAT plans (Table 1). For the planning challenge, a total of 30 participants registered interest. Of this, seven plans were submitted to the challenge. On average, participants generated a plan that would be acceptable based on our institutional constraints (Table 1). However, the volumetric dose to bowel and pelvic bones were higher on MR-LINAC plans compared to the reference VMAT plan. CONCLUSION MR-LINAC fixed-field IMRT for cervix cancer patients is feasible but system constraints and optimization implementation result in greater dose heterogeneity and worse organ-at-risk sparing compared to Linac based VMAT. Further research is needed to determine if potential reduction of treatment margins, allowed by better MRI soft-tissue visualization, will result in MR-LINAC IMRT superior to Linac VMAT.
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Zhang WH, Wen Z, Chai J, Du X, Wang Z, Fan LN. [Advances in molecular pathogenetic characteristics of clear cell papillary renal tumor]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2023; 52:880-884. [PMID: 37528003 DOI: 10.3760/cma.j.cn112151-20221226-01059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 08/03/2023]
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Lu M, Qu Y, Ma A, Zhu J, Zou X, Lin G, Li Y, Liu X, Wen Z. [Prediction of 1p/19q codeletion status in diffuse lower-grade glioma using multimodal MRI radiomics]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2023; 43:1023-1028. [PMID: 37439176 DOI: 10.12122/j.issn.1673-4254.2023.06.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 07/14/2023]
Abstract
OBJECTIVE To develop a noninvasive method for prediction of 1p/19q codeletion in diffuse lower-grade glioma (DLGG) based on multimodal magnetic resonance imaging (MRI) radiomics. METHODS We collected MRI data from 104 patients with pathologically confirmed DLGG between October, 2015 and September, 2022. A total of 535 radiomics features were extracted from T2WI, T1WI, FLAIR, CE-T1WI and DWI, including 70 morphological features, 90 first order features, and 375 texture features. We constructed logistic regression (LR), logistic regression least absolute shrinkage and selection operator (LRlasso), support vector machine (SVM) and Linear Discriminant Analysis (LDA) radiomics models and compared their predictive performance after 10-fold cross validation. The MRI images were reviewed by two radiologists independently for predicting the 1p/19q status. Receiver operating characteristic curves were used to evaluate classification performance of the radiomics models and the radiologists. RESULTS The 4 radiomics models (LR, LRlasso, SVM and LDA) achieved similar area under the curve (AUC) in the validation dataset (0.833, 0.819, 0.824 and 0.819, respectively; P>0.1), and their predictive performance was all superior to that of resident physicians of radiology (AUC=0.645, P=0.011, 0.022, 0.016, 0.030, respectively) and similar to that of attending physicians of radiology (AUC=0.838, P>0.05). CONCLUSION Multiparametric MRI radiomics models show good performance for noninvasive prediction of 1p/19q codeletion status in patients with in diffuse lower-grade glioma.
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Li W, Sun X, Wan B, Liu H, Fang J, Wen Z. A hybrid GA-PSO strategy for computing task offloading towards MES scenarios. PeerJ Comput Sci 2023; 9:e1273. [PMID: 37346691 PMCID: PMC10280386 DOI: 10.7717/peerj-cs.1273] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 02/13/2023] [Indexed: 06/23/2023]
Abstract
As a new type of computing paradigm closer to service terminals, mobile edge computing (MEC), can meet the requirements of computing-intensive and delay-sensitive applications. In addition, it can also reduce the burden on mobile terminals by offloading computing. Due to cost issues, results in the deployment density of mobile edge servers (MES) is restricted in real scenario, whereas the suitable MES should be chosen for better performance. Therefore, this article proposes a task offloading strategy under the sparse MES density deployment scenario. Commonly, mobile terminals may reach MES through varied access points (AP) based on multi-hop transmitting mode. The transmission delay and processing delay caused by the selection of AP and MES will affect the performance of MEC. For the purpose of reducing the transmission delay due to system load balancing and superfluous multi-hop, we formulated the multi-objective optimization problem. The optimization goals are the workload balancing of edge servers and the completion delay of all task offloading. We express the formulated system as an undirected and unweighted graph, and we propose a hybrid genetic particle swarm algorithm based on two-dimensional genes (GA-PSO). Simulation results show that the hybrid GA-PSO algorithm does not outperform state-of-the-art GA and NSA algorithms in obtaining all task offloading delays. However, the workload by standard deviation approach is about 90% lower than that of the GA and NSA algorithms, which effectively optimizes the performance of load balancing and verifies the effectiveness of the proposed algorithm.
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Tang X, Tian G, Huang Y, Ran J, Wen Z, Xu J, Song S, Liu B, Han R, Shi F, Zhang X, Sun H, Gong Y, Li Y, Zhang Z, Chen Z, Luo P. Activation cross sections for reactions induced by 14 MeV neutrons on natural titanium. Appl Radiat Isot 2023; 193:110636. [PMID: 36584411 DOI: 10.1016/j.apradiso.2022.110636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 11/22/2022] [Accepted: 12/23/2022] [Indexed: 12/28/2022]
Abstract
Cross sections for the neutrons around 14 MeV interaction with natural titanium were precisely measured by neutron activation and off-line measurement technique. The fast neutrons were produced by 3H(d,n)4He reaction and the neutron energy was obtained by using the cross section ratio method of 90Zr(n,2n)89Zr to 93Nb(n,2n)92mNb reactions. Experimental cross sections have been acquired for natTi(n,x)46Sc, natTi(n,x)47Sc, 50Ti(n,x)47Ca and 48Ti(n,x)48Sc reactions. The measured cross section data are compared with the experimental data available in the previous literature and evaluated nuclear data from the ENDF/B-VIII.0, JEFF-3.3, JENDL-5, BROND-3.1, CENDL-3.2 and FENDL-3.2b libraries. Furthermore, excitation functions for these reactions were calculated by using the theoretical model based on Talys-1.96 code with default and adjusted parameters. Within experimental error, evaluated nuclear data are mostly consistent with experimental data. The excitation function with adjusted parameters can roughly reproduce the experimental data.
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He SY, Qiu XM, Wang YQ, Su ZQ, Zhang BY, Wen Z, Yang YF, Xing BF, Hong M, Liao R. Intervention effect of Potentilla discolor-Euonymus alatus on intestinal flora of type 2 diabetes mellitus rats. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2022; 26:9062-9071. [PMID: 36591818 DOI: 10.26355/eurrev_202212_30655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVE With this study, we aimed at exploring the regulation mechanism of Potentilla discolor-Euonymus alatus on intestinal flora of T2DM (Type 2 Diabetes Mellitus) rats induced by high-fat diet combined with streptozotocin. MATERIALS AND METHODS T2DM rats were induced by high-fat diet combined with streptozotocin. There were normal control group, model group, metformin group, high-dose Chinese medicine group and low-dose Chinese medicine group. Each group included 10 rats. Normal control group: normal feeding, no modeling, ordinary feed, and gavage of 0.9% normal saline. Model group: T2DM rats, high-fat diet, and gavage of 0.9% normal saline. Metformin group: T2DM rats, high-fat diet and fed with metformin solution. High-dose Chinese medicine group: T2DM rats, high-fat diet, and gavage of concentrated Chinese medicine at a dose of 6 times the clinical dose. Low-dose Chinese medicine group: T2DM rats, high-fat diet, and gavage of concentrated Chinese medicine at a dose twice the clinical dose. The general situation of T2DM rats was observed, and the changes of intestinal flora were observed with 16SrDNA sequencing. RESULTS The T2DM rats induced by high-fat diet combined with streptozotocin were molded. After intervention, at the class level, the ratio of γ-proteobacteria was 22.30% in the model group, 11.97% in the metformin group, 3.24% in the high-dose Chinese herbs group and 1.72% in the low-dose Chinese herbs group; the ratio of Erysipelothrix insidiosa was 4.73% in the model group, 4.68% in the metformin group, 3.93% in the high-dose Chinese herbsgroup and 2.92% in the low dose group; the ratio of Lactinobacillus was 2.30% in the model group, 0.01% in the metformin group, 0.00% in the high-dose Chinese herbs group, and 0.00% low-dose Chinese herbs group; at the portal level, the Firmicutes/Bacteroides was 0.88 in the normal control group, 3.40 in the model group, 1.71 in the metformin group, 2.74 in high-dose Chinese medicine group, and 1.34 in low-dose Chinese medicine group; at the genus level, the relative abundance of Lactobacillus in the model group was 3.28%, that of Akkermansia was 1.99%, that of Shigella coli was 22.08%, and that of Vibrio phaseus was 7.67%. All of them were improved after the intervention of metformin and traditional Chinese medicine. CONCLUSIONS Potentilla discolor-Euonymus Alatus could improve the composition and structure of intestinal flora in T2DM rats and regulate the diversity of intestinal flora. The ratio of Firmicutes/Bacteroidetes was adjusted, mainly to increase the number of Bacteroides; the flora related to intestinal barrier was adjusted, mainly to increase the number of Lactobacillus and Akkermansia bacteria.
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Fang W, Bu Q, Wang Q, Zhao W, Wang L, Dong X, Chen P, Wen Z, Jia J, Jiang G, Zhang L. 373P Safety and efficacy of aumolertinib treatment in patients with advanced NSCLC harboring uncommon EGFR mutations: Cohort 2. Ann Oncol 2022. [DOI: 10.1016/j.annonc.2022.10.411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
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Werner E, Gokhale A, Ackert M, Xu C, Wen Z, Roberts AM, Roberts BR, Vrailas-Mortimer A, Crocker A, Faundez V. The mitochondrial RNA granule modulates manganese-dependent cell toxicity. Mol Biol Cell 2022; 33:ar108. [PMID: 35921164 DOI: 10.1091/mbc.e22-03-0096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Prolonged manganese exposure causes manganism, a neurodegenerative movement disorder. The identity of adaptive and nonadaptive cellular processes targeted by manganese remains mostly unexplored. Here we study mechanisms engaged by manganese in genetic cellular models known to increase susceptibility to manganese exposure, the plasma membrane manganese efflux transporter SLC30A10 and the mitochondrial Parkinson's gene PARK2. We found that SLC30A10 and PARK2 mutations as well as manganese exposure compromised the mitochondrial RNA granule composition and function, resulting in disruption of mitochondrial transcript processing. These RNA granule defects led to impaired assembly and function of the mitochondrial respiratory chain. Notably, cells that survived a cytotoxic manganese challenge had impaired RNA granule function, thus suggesting that this granule phenotype was adaptive. CRISPR gene editing of subunits of the mitochondrial RNA granule, FASTKD2 or DHX30, as well as pharmacological inhibition of mitochondrial transcription-translation, were protective rather than deleterious for survival of cells acutely exposed to manganese. Similarly, adult Drosophila mutants with defects in the mitochondrial RNA granule component scully were safeguarded from manganese-induced mortality. We conclude that impairment of the mitochondrial RNA granule function is a protective mechanism for acute manganese toxicity.
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Yinghua L, Wen Z, Yu W, Xiaoping S, Xian D, Yangguang G, Wei Z, Lu H. 616 Ultraviolet A mediates the keratinocytes supranuclear melanin cap formation via opsin 3. J Invest Dermatol 2022. [DOI: 10.1016/j.jid.2022.05.626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Qing YF, Huang Q, Zhao ZY, Zhang QB, Li LQ, Wen Z, You ZX, Tang H, Xu H. AB0334 EFFICACY AND SAFETY OF ABATACEPT IN CHINESE PATIENTS WITH ACTIVE RHEUMATOID ARTHRITIS: REAL-WORLD DATA. Ann Rheum Dis 2022. [DOI: 10.1136/annrheumdis-2022-eular.1198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BackgroundAbatacept (ABA) has demonstrated efficacy and safety in active rheumatoid arthritis (RA) patients in Europe and the United States as one of bDMARDs [1]. However, the clinical activity of Abatacept (ABA) has not been sufficiently investigated in patients with RA from a real-world clinical setting in China.ObjectivesThis study was designed to investigate the efficacy and safety of Abatacept in the RA patients in Chinese population who were refractory to csDMARDs, aiming to provide further reference for clinical rational drug use.MethodsClinical data of 55 patients with active RA who were admitted in the Affiliated Hospital of North Sichuan Medical College from June 2020 to June 2021 and did not respond to csDMARDs was retrospectively analyzed. Patients in this study were treated with Abatacept (125 mg by subcutaneous injection once weekly combined with csDMARDs. Changes in clinical manifestations, including DAS28-ESR, CDAI, ACR 20/50/70 at week 12 and 24 from baseline and AEs during 24 weeks were observed and recorded.Results55 patients (46 women and 9 men) were included in this study with a mean age 50.80 ± 12.46 and a mean disease duration of 6.29 ± 6.22 years. The ACR 20 response at week 12 and 24 was 50.91% (28/55) and 87.27% (48/55), respectively. Besides, DAS 28-ESR score were significantly lower at week 12 and 24 compared to baseline (P <0.05) with 19 patients (34.55%) achieving clinical remission or low disease activity. Changes in CDAI scores revealed that 80% patients achieved clinical remission or low disease activity at week 24. DAS28-ESR score was significantly lower in previously untreated patients (Biologic-naive) (n=36) (3.40 ± 0.81) than in the previously treated patients (Biologic non-naive) (n=19) (3.83 ± 0.68) (P = 0.02) (Figure 1). RF, CCP antibody and GLOB levels were significantlyreduced in RA patients after 24-week ABA treatment compared to baseline (P﹤0.05) (Table 1). Two hepatitis B virus (HBV) carriers, two patients with active tuberculosis and one patient with latent tuberculosis status showed no reactivation of HBV and no new active tuberculosis lesions 24 weeks after treatment with ABA. AEs were reported in 9.1% (5/55), but no serious infections occurred.Table 1.Analysis of clinical and serological parameters at baseline and after treatment with Abatacept.IndexesBaseline12 weeks24 weeksTJC6 (4,10)3 (2,4)*2 (1,3) **SJC2 (1,4)1 (0,2)*0 (0,1)**PtGA-VAS(0-10cm)8 (7,10)5 (3,6)*2(2,3)**HAQ2 (0,4)1 (0,2)*0 (0,1)**ESR (mm/h)51 (41,89)37 (28,51)*23 (17,37)**HsCRP(mg/L)14.08 (3.7,35.0)5,77 (2.27,20.78) *4.12 (1.34,9.37) **GLOB34.47±5.69-30.33±3.81*RF-IgM (IU/mL)408.55 (68.8,566.5)-167.41 (34.9, 171.25) *RF-IgG (U/mL)8.63 (4.55, 11.1)-7.94 (3.13, 6.23) *RF-IgA (U/mL)90.18 (25.63, 99.12)-58.20 (16.81, 59.09) *CCP (RU/mL)1095.45 (66.79, 1033.28)-782.0 (58.49, 857.5) **p﹤0.05,TJC=Tender joint count, SJC=Swollen joint count, GLOB= immunoglobulin.ConclusionIn the Chinese patients with active RA refractory to csDMARDs, the combination of ABA and csDMARDs showed great clinical efficacy and a favorable safety profile. Moreover, ABA resulted in better efficacy in patients previously untreated with biologics than previously treated with biologics.References[1]Weinblatt ME, Schiff M, Valente R,et al. Head-to-head comparison of subcutaneous abatacept versus adalimumab for rheumatoid arthritis: findings of a phase IIIb, multinational, prospective, randomized study. Arthritis Rheum 2013; 65:28-38.Disclosure of InterestsNone declared
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Wen Z, Huang G, Lai Y, Xiao L, Peng X, Liu K, Zhang C, Chen X, Li R, Li X, Lai Y, Ni L. Diagnostic panel of serum miR-125b-5p, miR-182-5p, and miR-200c-3p as non-invasive biomarkers for urothelial bladder cancer. Clin Transl Oncol 2022; 24:909-918. [PMID: 35028929 DOI: 10.1007/s12094-021-02741-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 11/23/2021] [Indexed: 02/05/2023]
Abstract
PURPOSE This study aimed to identify a diagnostic panel of serum microRNAs (miRNAs) for the early detection of bladder cancer (BC). METHODS Serum samples were collected from 112 BC patients and 112 normal controls (NCs). A three-stage selection was conducted to identify differentially expressed miRNAs as candidates to construct the diagnostic panel. Further, to explore their potential roles in urothelial BC, bioinformatics analyses, including target genes prediction and functional annotation, were used. RESULTS Six downregulated miRNAs (miR-1-3p, miR-30a-5p, miR-100-5p, miR-125b-5p, miR-143-3p, and miR-200c-3p) and one upregulated, miR-182-5p, in BC patients' serum were detected compared to NCs and were selected to establish the diagnostic panel. Based on a backward stepwise logistic regression analysis, miR-125b-5p, miR-182-5p, and miR-200c-3p comprehended the diagnostic panel [area under the curve (AUC) = 0.959, sensitivity = 91.67%, specificity = 92.5%]. CONCLUSION The panel of three miRNAs had an excellent diagnostic capability, representing a potential non-invasive method for early BC detection.
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Li L, Zou L, Yue W, Liu C, Wang H, Wen Z, Xiang Q, Ren G, Guo S, Fang J. MicroRNA-29a-3p regulates chemosensitivity in hypopharyngeal carcinoma via targeting Cdc42. THE MALAYSIAN JOURNAL OF PATHOLOGY 2022; 44:53-60. [PMID: 35484886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
INTRODUCTION Hypopharyngeal carcinoma is one kind of high malignant tumour followed by poor prognosis in head and neck carcinomas. This study aimed to detect miR-29a-3p and Cdc42 in patients with hypopharyngeal carcinoma. MATERIALS AND METHODS The expression of miR-29a-3p and Cdc42 mRNA were detected, and the correlation between miR-29a-3p/Cdc42 and clinical stages was investigated. RESULTS The relative expression of miR-29a-3p in stage II, III and IV hypopharyngeal carcinoma tissues was significantly lower than that of stage I (P< 0.05). The relative expression of Cdc42 mRNA in stage I, III and IV tissues was significantly higher than that of stage I (P< 0.05). The expression of miR-29a-3p in hypopharyngeal carcinoma with lymph node metastasis was significantly lower than that without lymph node metastasis (P = 0.045). CONCLUSION MiR-29a-3p and Cdc42 mRNA could be potential diagnostic biomarkers of hypopharyngeal carcinoma.
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Ren J, Wen Z. Distribution Characteristics of Cadmium and Arsenic in the Typical Vegetable Soil and the Sediment of its Irrigation Sources in Xijiang River Basin at the End of the Farming Slack Period. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2022; 108:801-807. [PMID: 35088101 DOI: 10.1007/s00128-021-03438-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 12/15/2021] [Indexed: 06/14/2023]
Abstract
We collected the farmland soil and the sediment, carried out sample speciation detection and distribution analyses, explored environmental self-purification on the distribution of Cd and As of agricultural sources. There were significant differences between total Cd and total As and between speciation distribution in the orders of magnitude. Total Cd (mean content was 1.74 mg kg-1) and total As (mean content was 32.31 mg kg-1) in all the samples were higher than the background contents. Cd distribution in the farmland soil was not significantly affected by geographical locations. As cumulative effect in riverside farmland soil was stronger, river irrigation and flooding may input more As, transformation mechanism of As may be exogenous input, binding and passive release. The bio-available proportions and risk assessment criteria of Cd were larger than As, the ecological risk of local Cd was higher than As, suggested to increase risk monitoring of Cd.
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Wen Z, Liang W, Zhong Y, Sun F, Zhang Q. [Expression of nicotinamide-N-methyltransferase in gastric cancer and its biological and clinicopathological significance]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2021; 41:828-838. [PMID: 34238734 PMCID: PMC8267982 DOI: 10.12122/j.issn.1673-4254.2021.06.04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To investigate the expression of nicotinamide-N-methyltransferase (NNMT) in gastric cancer (GC) and explore its biological and clinicopathological significance. OBJECTIVE We screened the candidate genes associated with the classification and prognosis of gastric cancer by analyzing GEO, Oncomine and TCGA datasets. The molecular pathways and protein interaction network involving these candidate genes were analyzed using STRING, GSEA, David and Cytoscape software. The expressions of the candidate genes in 28 pairs of gastric cancer and adjacent tissues were detected with qRTPCR, and CCK-8 assay, clone formation assay, wound healing assay and Transwell assay were carried out to analyze the effects of modulation of NNMT expression on proliferation, invasion and migration of different gastric cancer cell lines. OBJECTIVE NNMT was highly expressed in gastric cancer tissues and was negatively correlated with the prognosis of patients with gastric cancer. Pathway analysis showed that the high expression of NNMT was associated with adhesion-related pathway molecules such as extracellular matrix receptors, cell adhesion molecules, and cytokine receptors, while its low expression was associated with base mismatch repair and riboflavin metabolism. Protein interaction analysis showed that NNMT interacted with 16 differentially expressed proteins such as AURKA and was co-expressed with TAGLN, PTRF, AKAP12 and IGF2BP2. In clinical tissue specimens, qRT-PCR results showed that the expression of NNMT mRNA was significantly higher in gastric cancer tissues than in the adjacent tissues (P < 0.05). In gastric cancer cell lines, overexpression of NNMT was found to significantly promote cell proliferation, invasion and migration, while NNMT knockdown produced obvious inhibitory effects on cell proliferation, invasion and migration. OBJECTIVE NNMT is highly expressed in gastric cancer and negatively correlated with the prognosis of gastric cancer patients. The high expression of NNMT promotes the proliferation, invasion and metastasis of gastric cancer cells, suggesting the potential of NNMT as prognostic marker of gastric cancer.
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Zhang J, Zhang M, Fu R, Chu X, Wen Z, Gong Y, Jiang B, Liao R, Dong S, Nie Q, Chen R, Xia X, Yang X, Zhong W, Wu Y. P56.01 Postoperative ctDNA Positive Presents the High-risk of Recurrence in Resectable Non-Small Cell Lung Cancers. J Thorac Oncol 2021. [DOI: 10.1016/j.jtho.2021.01.944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Liu XJ, Xu W, Du EZ, Tang AH, Zhang Y, Zhang Y, Wen Z, Hao TX, Pan YP, Zhang L, Gu B, Zhao Y, Shen JL, Zhou F, Gao ZL, Feng Z, Chang YH, Goulding K, Collett J, Vitousek PM, Zhang F. Environmental impacts of nitrogen emissions in China and the role of policies in emission reduction. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2020; 378:20190324. [PMID: 32981443 PMCID: PMC7536030 DOI: 10.1098/rsta.2019.0324] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Atmospheric reactive nitrogen (Nr) has been a cause of serious environmental pollution in China. Historically, China used too little Nr in its agriculture to feed its population. However, with the rapid increase in N fertilizer use for food production and fossil fuel consumption for energy supply over the last four decades, increasing gaseous Nr species (e.g. NH3 and NOx) have been emitted to the atmosphere and then deposited as wet and dry deposition, with adverse impacts on air, water and soil quality as well as plant biodiversity and human health. This paper reviews the issues associated with this in a holistic way. The emissions, deposition, impacts, actions and regulations for the mitigation of atmospheric Nr are discussed systematically. Both NH3 and NOx make major contributions to environmental pollution but especially to the formation of secondary fine particulate matter (PM2.5), which impacts human health and light scattering (haze). In addition, atmospheric deposition of NH3 and NOx causes adverse impacts on terrestrial and aquatic ecosystems due to acidification and eutrophication. Regulations and practices introduced by China that meet the urgent need to reduce Nr emissions are explained and resulting effects on emissions are discussed. Recommendations for improving future N management for achieving 'win-win' outcomes for Chinese agricultural production and food supply, and human and environmental health, are described. This article is part of a discussion meeting issue 'Air quality, past present and future'.
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Liu Y, Wang H, Gao J, Wen Z, Peng L. Cryptotanshinone ameliorates the pathogenicity of Streptococcus suis by targeting suilysin and inflammation. J Appl Microbiol 2020; 130:736-744. [PMID: 32750224 DOI: 10.1111/jam.14810] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 07/22/2020] [Accepted: 07/29/2020] [Indexed: 12/22/2022]
Abstract
AIMS Streptococcus suis is a highly zoonotic pathogen that is a serious threat to human health and the development of the pig industry worldwide. The virulence factors produced during S. suis infection play an important role, and the pore-forming activity of suilysin is considered an important virulence-related factor, especially in meningitis. Treatment of S. suis infection with traditional antibiotics is becoming increasingly challenging due to bacterial resistance. The purpose of this study is to verify the role of cryptotanshinone in the process of S. suis infection and provide a new drug precursor for the treatment of S. suis infection. METHODS AND RESULTS In this study, we used circular dichroism spectroscopy to demonstrate that cryptotanshinone alters the secondary structure of suilysin. The results of the antibacterial activity and haemolysis assays showed cryptotanshinone could inhibit the pore-forming activity of suilysin without affecting bacterial growth or its expression. We also showed that cryptotanshinone reduces bacterial damage and penetration in vitro, reduce the S. suis-induced inflammatory response and provide protection against bacterial infections in vivo and in vitro. CONCLUSIONS Cryptotanshinone is a potential compound precursor for treating S. suis infection. SIGNIFICANCE AND IMPACT OF THE STUDY Cryptotanshinone may be a promising leading compound for S. suis infection and related diseases.
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Cai ZM, Wen Z. [Research progress in the application of intralymphatic allergen immunotherapy in allergic diseases]. LIN CHUANG ER BI YAN HOU TOU JING WAI KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY, HEAD, AND NECK SURGERY 2020; 33:1109-1112. [PMID: 31914307 DOI: 10.13201/j.issn.1001-1781.2019.11.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Indexed: 11/12/2022]
Abstract
SummaryAlthough subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) have a positive effect, there are drawbacks such as long treatment time period, frequent treatment times, and risk of adverse reactions. Peripheral superficial lymph node injection of allergen immunotherapy (ILIT) as an emerging specific immunotherapy method has the advantages of high safety, less adverse reactions, short treatment time, less treatment times, less patient pain, and exact curative effect. In recent years, more and more scholars have conducted extensive research on intra-lymphatic injection of immunotherapy for allergic diseases. This paper systematically summarizes the theoretical basis, method, safety, effectiveness and possible immune mechanism of ILIT.
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Wen Z, Zhao J, Liu YY, Zhou JJ, Liu C, Li C, Wu MC. Enantioconvergent hydrolysis of m-nitrostyrene oxide at an elevated concentration by Phaseolus vulgaris epoxide hydrolase in the organic/aqueous two-phase system. Lett Appl Microbiol 2019; 70:181-188. [PMID: 31784998 DOI: 10.1111/lam.13258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 11/21/2019] [Accepted: 11/26/2019] [Indexed: 11/30/2022]
Abstract
(R)-m-Nitrophenyl-1,2-ethanediol (m-NPED) is a versatile and highly value-added chiral building block for the synthesis of some bioactive compounds, such as (R)-Nifenalol. To efficiently produce (R)-m-NPED through the enantioconvergent hydrolysis of racemic (rac-) m-nitrostyrene oxide (m-NSO) using the whole resting cells of Escherichia coli/pCold-pveh2 intracellularly expressing PvEH2, an epoxide hydrolase from Phaseolus vulgaris, two reaction systems were investigated. In the Na2 HPO4 -NaH2 PO4 buffer (50 mmol l-1 , pH 7·0) system, merely 15 mmol l-1 rac-m-NSO was successfully subjected to enantioconvergent hydrolysis, producing (R)-m-NPED with 86·0% enantiomeric excess (eep ) and 177·6 mg l-1 h-1 space-time yield (STY). The experimental result indicated that there is inhibitory effect of rac-m-NSO at high concentration on PvEH2. To efficiently increase the concentration of rac-m-NSO and the STY of (R)-m-NPED, petroleum ether was first selected to construct an organic/aqueous two-phase system. Then, both the volume ratio (vo /vb ) of petroleum ether to phosphate buffer and the weight ratio (wc /ws ) of E. coli/pCold-pveh2 dry cells to rac-m-NSO were optimized as 2 : 8 and 5 : 1, respectively. In the optimized petroleum ether/phosphate buffer two-phase system, the enantioconvergent hydrolysis of rac-m-NSO at 40 mmol l-1 (6·6 mg ml-1 ) was carried out at 25°C for 12 h using 33·0 mg ml-1 vacuum freeze-dried cells of E. coli/pCold-pveh2, producing (R)-m-NPED with 87·4% eep , 82·3% yield and 502·4 mg l-1 h-1 STY. SIGNIFICANCE AND IMPACT OF THE STUDY: Epoxide hydrolases play a crucial role in producing enantiopure epoxides and/or vicinal diols. However, numerous biocatalytic reactions of organic compounds, such as epoxides, in aqueous phase suffered various restrictions. Herein, the enantioconvergent hydrolysis of rac-m-NSO in two reaction systems was investigated using the whole cells of Escherichia coli/pCold-pveh2. As a result, the concentration of rac-m-NSO and the space-time yield of (R)-m-NPED in organic/aqueous two-phase system were significantly increased, when compared with those in aqueous phase. To our knowledge, this is the first report about the production of (R)-m-NPED from rac-m-NSO at an elevated concentration by PvEH2 in the two-phase system.
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