Objective To establish and evaluate a method for determination of total arsenic in urine by test-tube rapid digestion hydride generation atomic fluorescence spectrometry.Methods After digestion of urine samples using graduated test-tube and graphite digestion apparatus,arsenic content in urine was determined with atomic fluorescence spectrometer.Then the test results were evaluated by using quality control measures,such as precision and accuracy experiments,and the results between different laboratories were reviewed and compared.Results The urinary arsenic was in a linear range of 0-0.300 mg/L,correlation coefficient (r) ＞ 0.999 3,detection limit was 0.000 21 mg/L,relative standard deviation (RSD) ≤4.62％ and the recoveries of standard addition were 93.9％-104.3％.The value of standard reference material measured was within the allowable range.The blind sample of the national urinary arsenic was qualified.Conclusions This method is suitable for large scale determination of urinary arsenic for its micro sample amount needed,less interference and strong practicability.The error results are in a controlled range.

Objective To investigate the mechanisms of tigecycline nonsusceptibility in carbapen-ems-resistant Acinetobacter baumannii ( CRAB) strains in order to provide a theoretical basis for a reasonable use of antibiotics and the control of nosocomial infection .Methods Susceptibility testing of 120 non-dupli-cate CRAB strains to tigecycline was performed by using the broth microdilution method .Minimal inhibitory concentrations ( MIC) of tigecycline against the A.baumannii strains were determined by using the broth mi-crodilution method before and after exposing the strains to Carbonylcyanide-m-chlorophenylhydrazone (CCCP), which was the efflux pump inhibitor .Polymerase chain reaction (PCR) was used to amply the ef-flux pumps genes including adeB, adeJ, adeG, abeM, adeE, adeRS, tetX and tetX1.The real-time PCR was performed to measure the expression of efflux pumps genes including adeB, adeJ, adeG, abeM and adeE.Results A total of 120 CRAB strains were collected including 13 (10.8%) tigecycline non-suscep-tible A.baumannii (TNAB) strains and 107 (89.2%) tigecycline susceptible A.baumannii (TSAB) strains.The MIC values of tigecline to the 120 CRAB strains were in a range of 0.25 μg/ml to 8 μg/ml. The adeR and adeJ genes were detected in 90.0%and 92.5%of the 120 CRAB strains, respectively.The positive rates of adeB, adeS, adeG and abeM genes among the 120 CRAB strains were all 94.2%.None of the three genes including adeE, tetX and tetX1 were detected .The mean expression levels of adeB and adeJ in TNAB strains were respectively increased by 18.69 folds and 5.46 folds as compared with those in sensi-tive strains.No significant increase in the expression of adeG and abeM genes was observed in TNAB strains . A 4-fold decrease in the MIC was observed in 8 out of 13 TNAB isolates treated with 10 μg/ml of CCCP .The CCCP could partially reverse the resistance pattern of tigecycline .Conclusion The efflux pump sys-tems of adeABC and adeIJK rather than the abeFGH and abeM systems might play an important role in reduc-ing the tigecycline susceptibility in carbapenems-resistant A.baumannii strains.

Objective To assess the diagnostic accuracy of solitary pulmonary nodules while selecting different backgrounds in 99 Tcm‐MIBI SPECT/CT examination .Methods Totally 38 suspected solitary pulmonary nodules (SPN) were analyzed retrospectively .The lesions were divided into malignant group and benign group according to the pathological findings . We selected two different backgrounds , contralateral lung field ( DL ) and the contralateral soft tissue (NST) .The maximum counts and the mean counts of lesion to non‐lesion ratio (L/N) were calculated to evaluate diagnostic efficacy using ROC curve . The relationship between lesion size , pathological grading and L/N ratio was analyzed by Spearman correlation analysis . Results With DL and NST as the backgrounds ,the maximum counts and the mean counts of L/N between benign and malignant groups both differed significantly (all P<0 .05) .ROC curve analysis showed as follows :With DL and NST as the backgrounds ,the area under the curve (AUC) of L/DL‐MAX ,L/DL‐MEAN ,L/NST‐MAX ,and L/NST‐MEAN was 0 .73 ,0 .78 ,0 .80 and 0 .86 ,respectively .By pairwise comparison ,there was no significant difference (all P>0 .05) .The size and pathological grading of SPN did not affect 99 Tcm‐MIBI accumulation in the SPN (all P>0 .05) .Conclusion DL and NST both can be used as the background in diagnosis of pulmonary nodules on 99 Tcm‐MIBI SPECT/CT examination .The mean counts of the contralateral tissue used as the background can provide a stable result and a high diagnostic accuracy to assess the SPN .

Ischemic stroke is one of the most important causes of death and disability in humans,but the effective methods for treating brain injury after stroke are quite limited.Sphingosine 1-phosphate (S1P) is a pleiotropic lipid.There is certain interdependence between its metabolism and regulation and the molecular mechanisms involved in important biological events following cerebral ischemia.Membrane lipid therapy with S1P as the core may be an effective neuroprotective strategy of ischemic stroke.

Objective:To explore whether thyroxine (T 4) could promote differentiated thyroid cancer (DTC) progression by binding to integrin α vβ 3in vitro and its downstream mechanism. Methods:Papillary thyroid cancer cell lines TPC-1, K1 and follicular thyroid cancer (FTC) cell line FTC133 were cultured in vitro, and the expressions of integrin α vβ 3 in those 3 DTC cell lines were determined with immunofluorescence and flow cytometry analysis. After the treatment of T 4, tetraiodo thyroacetic acid (Tetrac) and Arg-Gly-Asp (RGD) peptide alone or in combination, the proliferation and metastatic potential of DTC cell lines were detected by cell counting kit-8 (CCK-8), Transwell migration and invasion assays. The small interfering RNA (siRNA) transfection was used to verify whether integrin α v or β 3 subunit knockdown could reverse the effect of T 4 on DTC cells. The expression levels of downstream signaling proteins phosphorylated extracellular signal-regulated kinase (p-ERK)1/2 and total extracellular signal-regulated kinase (ERK)1/2 were detected by Western blot. The effects of mitogen-activated protein kinase kinase (MEK)1/2 inhibitor (GSK1120212) on the proliferation, migration and invasion of T 4-treated cells were detected. One-way analysis of variance and Tukey test were used for data analysis. Results:The integrin α vβ 3 expressions in TPC-1, K1 and FTC133 cells were all positive, with the relative mean fluorescence intensity (MFI) of 61.93±18.61, 16.89±2.43 and 32.36±0.83, and the percentages of positive cells of (94.38±1.30)%, (74.11±3.87)% and (50.67±1.78)%, respectively ( F values: 13.36 and 217.30, P=0.006 and P<0.001). Compared with control group, the proliferation, migration and invasion in the three DTC cell lines treated with T 4 were significantly enhanced (96 h, F values: 62.67-297.50, q values: 13.15-20.73, all P<0.001). T 4-induced cell proliferation, migration and invasion were markedly reversed by Tetrac or RGD (96 h, q values: 8.61-17.54, all P<0.001). T 4-induced cell proliferation, migration and invasion were also significantly inhibited by the knockdown of integrin α v or β 3 subunit (72 h, F values: 7.75-70.98, q values: 4.77-15.21, all P<0.05). Western blot results showed that the phosphorylation levels of ERK1/2 in DTC cells were significantly increased by T 4 treatment, and the T 4-induced activation of ERK1/2 signaling pathway could be blocked by Tetrac, RGD, integrin α v or β 3 subunit knockdown. T 4-induced cell proliferation, migration and invasion were significantly reversed by GSK1120212 (96 h, F values: 47.53-151.40, q values: 10.32-16.65, all P<0.001). Conclusion:T 4 can promote cell proliferation and metastasis of DTC cells by binding to integrin α vβ 3 and activating the ERK1/2 pathway.

Idiopathic pulmonary fibrosis (IPF) is a progressive scar-forming disease with a high mortality rate that has received widespread attention. Epithelial mesenchymal transition (EMT) is an important part of the pulmonary fibrosis process, and changes in the biomechanical properties of lung tissue have an important impact on it. In this paper, we summarize the changes in the biomechanical microenvironment of lung tissue in IPF-EMT in recent years, and provide a systematic review on the effects of alterations in the mechanical microenvironment in pulmonary fibrosis on the process of EMT, the effects of mechanical factors on the behavior of alveolar epithelial cells in EMT and the biomechanical signaling in EMT, in order to provide new references for the research on the prevention and treatment of IPF.
Humans ; Epithelial-Mesenchymal Transition ; Idiopathic Pulmonary Fibrosis ; Signal Transduction

Prostate cancer （PCa） is one of the most common malignant tumors in the male genitourinary system. The phosphatidylinositol 3-kinase （PI3K）/protein kinase B （Akt） signaling pathway is a carcinogenic pathway responsible for the migration， proliferation， and drug resistance of various cancers. In recent years， as the research on the pathogenesis of PCa is deepening， the role of the PI3K/Akt signaling pathway in the development of PCa has attracted much attention. Traditional Chinese medicine， comprehensively regulating multiple components， targets， and pathways， has shown great potential in the treatment of PCa. This article reviews the research progress of traditional Chinese medicine targeting the PI3K/Akt signaling pathway in the treatment of PCa and discusses the expression of the PI3K/Akt signaling pathway in PCa， which involves inhibiting apoptosis of PCa cells， promoting the cell cycle， invasion， and migration of PCa cells， promoting tumor tissue angiogenesis， and mediating the androgen receptor. Additionally， it summarizes the single Chinese medicines that target and regulate this pathway， including Hedyotis diffusa， Taxus chinensis， Bovisc Alculus， and Atractylodis Macrocephalae Rhizoma. The active ingredients of these Chinese medicines mainly include flavonoids， alkaloids， terpenes， polyphenols， lignans， and other compounds. The Chinese medicine compound prescriptions targeting the PI3K/Akt pathway mainly include Wenshen Sanjie prescription， Jianspi Lishi Huayu prescription， Yishen Tonglongtang， Qilan prescription， Xihuangwan， and modified Shenqi Dihuangtang. This review is expected to provide a scientific basis for deeply understanding the pathogenesis of PCa and identifying potential therapeutic targets， as well as to provide new ideas for clinical research and drug development for PCa.