Objective:To analyze the changes and significance in clinical cardiac indicators of early cardiac myocardial dysfunction and cardiac substructure dose during conventional radiotherapy for N 2-N 3 non-small cell lung cancer (NSCLC) with mediastinal lymph node metastases. Methods:The data of 34 NSCLC patients with lymph node metastases in regions 4-8 admitted to the Affiliated Cancer Hospital of Guizhou Medical University from June 2022 to August 2023 were observed and analyzed. All patients were treated with volumetric modulated arc therapy with a prescribed dose of 60-70 Gy. Cardiac troponin T (cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were measured at 6 time points: within 1 week before radiotherapy ( t0); when the cumulative radiotherapy dose reaches 20 Gy ( t20), 40 Gy ( t40), 60 Gy ( t60) during radiotherapy; within 1 week after radiotherapy ( tp); 1 month after radiotherapy( tp1). Left ventricular global longitudinal strain (LVGLS) and left atrial global longitudinal strain (LAGLS) were assessed at 4 time points: t0, t40, tp and tp1, respectively. The changes in cardiac indicators at different time points during radiotherapy and their correlation with substructure doses were analyzed using analysis of variance, linear regression analysis, and Pearson correlation. Results:The correlation between cardiac substructure dose and mean heart dose (MHD) in the study cohort in the descending order was as follows: left ventricle ( B=0.43, P<0.001), right ventricle ( B=0.37, P=0.002), left atrium ( B=0.16, P<0.001), and right atrium ( B=0.15, P=0.001). There were significant differences in the changes of LVGLS and LAGLS across different time points ( F=3.13, P=0.029; F=17.18, P<0.001). At 1 month after radiation, LAGLS was significantly decreased compared to pre-radiation levels ( P=0.009), whereas no significant difference was observed in LVGLS ( P=1.000). No significant differences were observed in the changes of cTnT and NT-proBNP across different time points (all P>0.05). Significant correlations were identified between cTnT and right ventricle mean dose at t40 ( r=0.38, P=0.025), as well as between NT-proBNP and right atrium mean dose at t60 and tp ( r=0.54, P=0.001; r=0.41, P=0.016). Conclusions:At present, there is no significant difference between the sensitive serum markers of myocardial injury and LVGLS in detecting early myocardial injury. LAGLS may hold substantial clinical value. There is uncertainty about radiation injury and repair of various cardiac substructures.

Objective:To analyze the changes and significance in clinical cardiac indicators of early cardiac myocardial dysfunction and cardiac substructure dose during conventional radiotherapy for N 2-N 3 non-small cell lung cancer (NSCLC) with mediastinal lymph node metastases. Methods:The data of 34 NSCLC patients with lymph node metastases in regions 4-8 admitted to the Affiliated Cancer Hospital of Guizhou Medical University from June 2022 to August 2023 were observed and analyzed. All patients were treated with volumetric modulated arc therapy with a prescribed dose of 60-70 Gy. Cardiac troponin T (cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were measured at 6 time points: within 1 week before radiotherapy ( t0); when the cumulative radiotherapy dose reaches 20 Gy ( t20), 40 Gy ( t40), 60 Gy ( t60) during radiotherapy; within 1 week after radiotherapy ( tp); 1 month after radiotherapy( tp1). Left ventricular global longitudinal strain (LVGLS) and left atrial global longitudinal strain (LAGLS) were assessed at 4 time points: t0, t40, tp and tp1, respectively. The changes in cardiac indicators at different time points during radiotherapy and their correlation with substructure doses were analyzed using analysis of variance, linear regression analysis, and Pearson correlation. Results:The correlation between cardiac substructure dose and mean heart dose (MHD) in the study cohort in the descending order was as follows: left ventricle ( B=0.43, P<0.001), right ventricle ( B=0.37, P=0.002), left atrium ( B=0.16, P<0.001), and right atrium ( B=0.15, P=0.001). There were significant differences in the changes of LVGLS and LAGLS across different time points ( F=3.13, P=0.029; F=17.18, P<0.001). At 1 month after radiation, LAGLS was significantly decreased compared to pre-radiation levels ( P=0.009), whereas no significant difference was observed in LVGLS ( P=1.000). No significant differences were observed in the changes of cTnT and NT-proBNP across different time points (all P>0.05). Significant correlations were identified between cTnT and right ventricle mean dose at t40 ( r=0.38, P=0.025), as well as between NT-proBNP and right atrium mean dose at t60 and tp ( r=0.54, P=0.001; r=0.41, P=0.016). Conclusions:At present, there is no significant difference between the sensitive serum markers of myocardial injury and LVGLS in detecting early myocardial injury. LAGLS may hold substantial clinical value. There is uncertainty about radiation injury and repair of various cardiac substructures.

Objective To investigate the effect and mechanism of dibenzazepines ( DBZ ) injection on pulmonary hypertension in rat. Methods Rat models of pulmonary hypertension were established, and 30 male rats were randomly divided into 3 groups: normal control group with saline injection, pulmonary hypertension model control group with hypoxia treatment and saline injection, DBZ group with hypoxia treatment and DBZ injection. The right ventricular pressure was determined by ultrasound cardiogram.Pulmonary arterial remodeling was detected by HE staining.Proliferation cell nuclear antigen and CCK-8 in pulmonary arterial smooth muscle cells were detected by Western blotting. Results The right ventricular pressure of pulmonary hypertension group was significantly increased compared with normal control group [(4.60±0.16) kPa vs. (3.37±0.18) kPa(P<0.01)].After hypoxia treatment, pulmonary arterial remodeling and proliferation of pulmonary arterial smooth muscle cells of the rats of pulmonary hypertension group were augmented remarkably. Rats from DBZ group showed reductions in right ventricular pressure, amelioration in pulmonary arterial remodeling and suppression in proliferation of pulmonary arterial smooth muscle cells. The proliferation of rat pulmonary artery smooth muscle cells decreased significantly in DBZ treated group [(2.073±0.064) vs.(4.392±0.013)] compared with model control group (P<0.05). Conclusion Notch pathway takes part in the process of pulmonary hypertension, and DBZ injection can significantly suppress the proliferation of pulmonary artery smooth muscle cells with a protective effect on pulmonary hypertension.

Objective To detect the intestinal pathogenic bacteria quickly and accurately from water. Methods An experimental procedure is set up using the gene chip technology to detect and identify common intestinal pathogenic bacteria from water. Target gene was amplified and hybridized with prepared gene chip.Results 143 strains of bacteria in pure culture belong to 9 genera are successfully discriminated under comparatively same condition and a series of specific hybridization maps corresponding to each kinds of bacteria are obtained.Conclusions Salmonella spp., Shigella spp., Staphylococcus spp., Proteus spp., Escherichia coli, Yersinia enterocolitica, Listeria monocytogenes and Vibrio parahaemolyticus are detected and identified by the technology of gene chip. The accuracy, range, and discriminatory power of the assay can be continually improved by adding further oligonueleotides to the arrays without significantly increasing complexity or cost.

Objective To screen and seperate nitrobacteria that could be used to treat nitrogenous compound pollution.Methods Autotrophic nitrite-oxidizing microorganisms were screened by enrichment culture from soil.After morphological and biological detection,primers were designed to detect the distinctive gene norB of nitrobacteria.The PCR production was se-quenced,and the homology was identified according to the sequence in Genbank.Results One strain of bacterium was screened that could oxidize nitrite.This bacterium was small,light-yellow bacilli.The expected-size DNA fragments could be amplicated by PCR.The sequence of a PCR production was blasted in Genbank and showed99%consistent with norB gene of N hamburgensis.Conclusion It was preliminarily confirmed that the microorganism screened in this study might be nitrobac-terium.

Objective To amplify and sequence the distinctive norB gene of Nitrobacterium. Methods The norB gene was amplified by PCR and was cloned into T-vector and then transformed into E.coli JM109. After white-and-blue selection, positive colonies were sequenced with T7 sequencing primers by Takara Company. Spliced with Vector NTI Suite software, the homologous analysis of sequences were conducted in Genbank through Internet. Results The results showed that all of norB genes obtained from the nitrite-oxidizing bacteria were homologous with the norB gene of Nitrobacterium hamburgensis in Genbank. The homology ranged from 96% to 98%, and there were no frameshift mutations, which guaranteed the correct ORF. Conclusion The obtained genes are norB genes indeed.