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Soil samples, which were collected from three typical forests, i.e., Betula ermanii forest, coniferous mixed broad-leaved forest, and Pinus koraiensis forest, at different altitudes along the southern slope of Laotuding Mountain of Changbai Mountain range in Liaoning Province of China, were incubated over a temperature gradient in laboratory. Soil organic carbon mineralization rates (Cmin), soil β-1,4-glucosidase (βG) kinetics and their temperature sensitivity (Q10) were measured. The results showed that both altitude and temperature had significant effects on Cmin. Cmin increased with temperature and was highest in the B. ermanii forest. The temperature sensitivity of Cmin [Q10(Cmin)] ranked in order of B. ermanii forest > P. koraiensis forest > coniferous mixed broad-leaved forest, but did not differ significantly among the three forests. Both the maximum activity (Vmax) and the Michaelis constant (Km) of the βG responded positively to temperature for all the forests. The temperature sensitivity of Vmax [Q10(Vmax)] ranged from 1.78 to 1.90, and the temperature sensitivity of Km [Q10(Km)] ranged from 1.79 to 2.00. The Q10(Vmax)/Q10(Km) ratios were significantly greater in the B. ermanii soil than in the other two forest soils, suggesting that the βG kinetics-dependent impacts of the global warming or temperature increase on the decomposition of soil-organic carbon were temperature sensitive for the forests at the higher altitudes. [ABSTRACT FROM AUTHOR]

Tetracycline (TC) and Cu(II) coexist commonly in various waters, which may infiltrate into the subterranean environment through runoff and leaching, resulting in substantial ecological risks. However, the underlying mechanisms why Cu(II) affects the transport of TC in porous media remain to be further explored and supported by more evidence, especially the role of complexation. In this study, the transport of TC with coexisting Cu(II) was comprehensively explored with column experiments and density functional theory (DFT) calculation. At natural environmental concentrations, Cu(II) significantly inhibited the transport of TC in the quartz sand column. Cu(II) augmented the retention of TC in the column mainly via electrostatic force and complexation. The interaction between TC and TC-Cu complexes on the surface of SiO 2 was investigated with first-principles calculations for the first time. There were strong van der Waals forces and coordination bonds on the surface of complexes and SiO 2 , leading to higher adsorption energy than that of TC and inhibiting its penetration. This study offers novel insights and theoretical framework for the transport of antibiotics in the presence of metal ions to better understand the fate of antibiotics in nature.

This study investigated the role and mechanism of ligustilide(LIG) in attenuating oxygen-glucose deprivation/reoxyge-nation(OGD/R)-induced damage to mouse hippocampal neuron cells(HT22) by inhibiting ferroptosis through mitochondrial ferritin(FtMt). An in vitro model of OGD/R-induced HT22 cell damage was established. HT22 cells were randomly divided into normal group, model group, LIG groups(5, 10, and 20 μmol·L~(-1)), and ferrostatin-1(Fer-1, 2 μmol·L~(-1)) group. Cell viability was mea-sured using the CCK-8 method, and lactate dehydrogenase(LDH) release was measured using an LDH assay kit. Cell morphology was observed under an inverted microscope, and mitochondrial ultrastructure was observed using transmission electron microscopy. Intracellular Fe~(2+) content was detected using a chemiluminescence method. To further investigate the mechanism of FtMt inhibition of ferroptosis, FtMt in HT22 cells was silenced and divided into normal group, model group, LIG group(20 μmol·L~(-1)), si-NC group, si-FtMt group, and si-FtMt+20 μmol·L~(-1) LIG group. Immunofluorescence and Western blot were used to detect FtMt expression. Chemiluminescence was used to measure the content of NADPH/NADP~+, GSH, MDA, and ATP in HT22 cells. The mtROS fluorescence intensity was observed by laser confocal microscopy, and intracellular Fe~(2+) content was measured by flow cytometry. The expression of ferroptosis-related proteins Ferrtin, GPX4, and ACSL4 was detected by Western blot. The results showed that compared with the model group, LIG significantly increased the survival rate of HT22 cells, improved the morphology of damaged HT22 cells and mitochondrial ultrastructure, decreased intracellular Fe~(2+) content, and reduced the expression of the pro-ferroptosis protein ACSL4 while increasing the expression of anti-ferroptosis proteins Ferrtin and GPX4. After silencing FtMt, LIG promoted FtMt expression. Compared with the si-FtMt group, LIG significantly increased the content of NADPH/NADP~+ and GSH, reduced mtROS fluorescence intensity and MDA content, increased ATP activity, decreased intracellular Fe~(2+) content, inhibited the expression of pro-ferroptosis protein ACSL4, and increased the expression of anti-ferroptosis proteins Ferrtin and GPX4. In summary, LIG improved mitochondrial function by upregula-ting FtMt expression to inhibit ferroptosis, thereby alleviating OGD/R-induced damage to HT22 cells.

Objective: To study the drug resistance of Mycoplasma pneumoniae (MP) in the bronchoalveolar lavage fluid (BALF) of children with refractory Mycoplasma pneumoniae pneumonia (RMPP) and the distribution of drug-resistance genes, as well as the association of alleles at 2063 locus of 23SrRNA V region central ring with resistance to antimicrobial drugs., Methods: BALF specimens were collected from 245 children with RMPP who were admitted to the Children's Hospital Affiliated to Zhengzhou University from March 2016 to December 2020. A rapid cultured drug sensitivity assay was used to detect the resistance of MP isolates to nine commonly used antimicrobial drugs. The real-time PCR was used to measure MP DNA. The direct sequencing was used to detect gene mutations in MP 23SrRNA V region central ring., Results: Among the 245 BALF specimens, 207 tested positive for MP DNA, with a positive rate of 84.5%. The results of drug susceptibility test showed that the children with RMPP had a resistance rate of > 70% to macrolide antimicrobial drugs, with the highest resistance rate to clarithromycin, followed by roxithromycin, clindamycin, acetylspiramycin, erythromycin, and azithromycin, and these children had a resistance rate of < 5% to quinolone antimicrobial drugs. Among the 207 MP DNA-positive specimens, 41 (19.8%) had no drug-resistance gene mutations and 166 (80.2%) had drug-resistance gene mutations, among which 154 (74.4%) had an A→G mutation at 2063 locus of 23SrRNA V region central ring, 7 (3.4%) had an A→G mutation at 2064 locus, and 5 (2.4%) had mutations in both 2063 and 2064 loci. Among the 166 specimens with point mutations of the MP 23SrRNA gene, 159 (95.8%) had point mutations at 2063 locus. The A→G point mutation at 2063 locus of 23SrRNA V region central ring had a great impact on resistance to macrolide antimicrobial drugs. There was a significant difference in the distribution of alleles at 2063 locus between the children with resistance to clarithromycin, roxithromycin, clindamycin, acetylspiramycin, erythromycin, and azithromycin ( P < 0.05)., Conclusions: MP in the BALF of children with RMPP has a relatively high resistance rate to macrolide antimicrobial drugs. Resistance to macrolide antimicrobial drugs is closely associated with the A→G point mutation in the 23SrRNA gene, and the point mutation at 2063 locus of 23SrRNA V region central ring may affect the drug-resistance mechanism of MP.

Coastal wetland, affected by the interaction of land and marine ecosystems, is a typical fragile and sensitive zone. Spartina alterniflora is the most successful invasive species in global coastal zone, with important impact on coastal wetland ecosystems. We systematically summarized available literature, and reviewed the effects of S. alterniflora invasion on biogeochemical cycling (soil carbon, nitrogen, phosphorus cycling, and soil heavy metal migration) and biological community (microorganisms, plants, and animals) in coastal wetlands. Then, three perspectives were proposed for the future research: 1) strengthening the mechanism of the impact of S. alterniflora invasion on ecosystem health of coastal wetlands; 2) focusing on the coupling mechanism of the interaction between S. alterniflora community and coastal wetland environment in the context of global change; 3) carrying out long-term positioning monitoring to clarify the responses of coastal wetlands at different stages of S. alterniflora invasion. This review could provide guidance for the ecological utilization and management of S. alterniflora.

Baeckea frutescens is a medicinal plant distributing from Southeast Asia to Australia. A pair of novel diastereomeric C -methylated triflavonoids named baeckeins L ( 1 ) and M ( 2 ) were isolated from the roots of B. frutescens . The structures of these isolates were elucidated by analysis of the 1D ( 1 H/ 13 C) and 2D NMR (HSQC/HMBC/NOESY) and HR-ESI-MS spectroscopic data, and the absolute configurations of chiral carbons (C-2/C-3/C-2°/C-3°) were established by CD spectrometry combined with quantum chemical calculations.

Objective: To study the significance of plasma neutrophil extracellular trap (NET) and its markers in the diagnosis of community-acquired pneumonia (CAP) in children., Methods: A total of 160 children with CAP were enrolled as the CAP group, and 50 healthy children were enrolled the control group. According to disease severity, the CAP group was further divided into a mild CAP subgroup with 137 children and a severe CAP subgroup with 23 children. According to the pathogen, the CAP group was further divided into a bacterial pneumonia subgroup with 78 children, a Mycoplasma pneumonia subgroup with 35 children, and a viral pneumonia subgroup with 47 children. The levels of plasma NET and its markers [antibacterial peptide (LL-37), extracellular free DNA (cfDNA), and deoxyribonuclease I (DNase I)] were measured. Receiver operating characteristic (ROC) curve was used to analyze the value of each index in diagnosing CAP and assessing its severity., Results: Compared with the control group, the CAP group had significant increases in the levels of NET, LL-37, and cfDNA and a significant reduction in the activity of DNase I (P<0.05). Compared with the mild CAP subgroup, the severe CAP subgroup had significantly higher levels of NET, LL-37 and cfDNA and a significantly lower activity of DNase I (P<0.05). There were no significant differences in the levels of NET, LL-37, and cfDNA and the activity of DNase I among the bacterial pneumonia, Mycoplasma pneumonia, and viral pneumonia subgroups (P>0.05). In the CAP group, plasma NET levels were positively correlated with white blood cell count (WBC), percentage of neutrophils, and serum levels of C-reactive protein (CRP), procalcitonin and tumor necrosis factor-α (r=0.166, 0.168, 0.275, 0.181 and 0.173 respectively, P<0.05); LL-37 and cfDNA levels were positively correlated with WBC (r=0.186 and 0.338 respectively, P<0.05) and CRP levels (r=0.309 and 0.274 respectively, P<0.05); the activity of DNase I was negatively correlated with CRP levels (r=-0.482, P<0.05). The ROC curve analysis showed that NET, LL-37, cfDNA, and DNase I had an area under the ROC curve (AUC) of 0.844, 0.648, 0.727, and 0.913 respectively in the diagnosis of CAP, with optimal cut-off values of 182.89, 46.26 ng/mL, 233.13 ng/mL, and 0.39 U/mL respectively, sensitivities of 88.12%, 35.63%, 54.37%, and 91.25% respectively, and specificities of 74.00%, 92.00%, 86.00%, and 76.00% respectively. In the assessment of the severity of CAP, NET, LL-37, cfDNA, and DNase I had an AUC of 0.873, 0.924, 0.820, and 0.778 respectively, with optimal cut-off values of 257.7, 49.11 ng/mL, 252.54 ng/mL, and 0.29 U/mL respectively, sensitivities of 83.21%, 86.96%, 78.26%, and 95.65% respectively, and specificities of 78.26%, 83.94%, 76.64%, and 56.93% respectively., Conclusions: Plasma NET and its related markers have a certain value in diagnosing CAP and assessing its severity in children.

Objective: To compare the effects of electroacupuncture (EA) at "Zusanli" (ST 36) versus "Yanglingquan" (GB 34) in the pregnant rats on perinatal nicotine - exposure - induced lung function and morphology of newborn rats and explore the rule of acupoint effect in EA for the prevention from lung dysplasia in newborn rats., Methods: A total of 24 female SD rats were randomized into a normal saline group (S group), a nicotine group (N group), a nicotine - ST 36 group (N + ST 36 group) and a nicotine - GB 34 group (N+GB 34 group), 6 rats in each one. Starting at the 6th day of pregnancy, 0.9% sodium chloride solution was injected subcutaneously in the S group, 1 mg/kg; and in the rest 3 groups, nicotine of the same dose was injected through to the 21st postnatal day to establish the perinatal nicotine - exposure model. Simultaneously, during model preparation, EA was applied at "Zusanli" (ST 36) and "Yanglingquan" (GB 34) in the N+ST 36 group and the N+GB 34 group respectively, once a day, through to the 21st postnatal day. The lung function analytic system for small animal was adopted to observe the changes in lung function indicators in newborn rats, such as peak inspiratory flow (PIF), peak expiratory flow (PEF), expiratory resistance (RE), inspiratory resistance (RI) and dynamic compliance (Cdyn). HE staining was used to observe the morphological changes of lung, such as alveolar fusion and rupture., Results: Compared with the S group, PEF and Cdyn were lower and PIF, RI and RE higher in the N group (all P <0.01), additionally, alveoli were fused and ruptured, alveolar wall thickened, the numbers of alveoli reduced, the interspace of alveoli enlarged and the diameter increased ( P <0.01). Compared with the N group, in the N+ST 36 group, PEF and Cdyn were increased, PIF, RI and RE reduced ( P <0.05, P <0.01), the alveolar fusion and rupture relieved, the numbers of alveoli increased, alveolar wall thinner, the interpsace of alveoli became normal and the diameter was reduced significantly ( P <0.01). In the N+GB 34 group, the changes of lung function and morphological indicators were not significant ( P >0.05)., Conclusion: Electroacupuncture at "Zusanli" (ST 36) in the pregnant rats significantly improves the perinatal nicotine - exposure - induced lung function and morphology of newborn rats than electroacupuncture at "Yanglingquan" (GB 34).

The water chemistry data monitored during 2010-2015 by 33 terrestrial ecological stations from the Chinese Ecosystem Research Network (CERN) and the National Ecosystem Research Network of China (CNERN) were used to characterize ion concentrations and their spatial variability in underground water, still surface water, and flowing surface water from typical terrestrial ecosystems. The results showed the presence of mass-based concentrations of major anions, including HCO 3 - > SO 4 2- > Cl - > CO 3 2- . Among them, HCO 3 - and SO 4 2- were dominant, and their sums accounted for 71.7%, 75.3%, and 74.9% of the total anions in underground water, still surface water, and flowing surface water, respectively. Cations were mainly Ca 2+ and Na + , and their sums accounted for 69.7%, 64.8%, and 68.9% of the total cations in underground water, still surface water, and flowing surface water, respectively. The ion concentration and ion ratio in the underground water, still surface water, and flowing surface water differed largely among the studied regions. The hydrochemical type varied regionally, e.g., Na-Mg-SO 4 -Cl type, usually with high content of salinity, was found in the underground water of ecological systems in the Northwest arid and semiarid areas and in the East Huanghuaihai Plain; Ca-SO 4 -HCO 3 type in underground water and Ca-HCO 3 -SO 4 type in surface water were found in hilly areas with subtropical red soil; Na-Ca-HCO 3 -Cl type was present in underground water of south hilly areas with subtropical latosolic red soil; and Ca-HCO 3 and Ca-Mg-HCO 3 types were found in other ecological systems. Hydrochemical types had low inter-annual variation for both underground water and surface water.

Objective: To compare the different effect of electroacupuncture (EA) at "Zusanli" (ST36) and "Chize" (LU5) of mother rats exposed to Nicotine during pregnancy and lactation on lung function and morphological changes in offspring rats, so as to explore the most effective acupoint for improving the development of lung in neonatal rats., Methods: A total of 24 female pregnancy SD rats were randomly divided into 4 groups: normal control, model, EA-ST36 and EA-LU5 ( n ＝6 rats in each group). Rats of the normal group were treated by subcutaneous injection of normal saline, and those of the other 3 groups treated by subcutaneous injection of nicotine (1 mg•kg －1 •d －1 ) beginning from the 6 th day to about the 21 st day of pregnancy (childbirth day) for nicotine exposure during pregnancy and lactation. The daily EA treatment (2 Hz /15 Hz，1 mA) was applied to bilateral ST36 and LU5 for 20 min, beginning from the 6 th day of pregnancy to the 21 st day (childbirth day). The lung function of the offspring rats including the peak inspiratory flow (PIF), peak expiratory flow (PEF), lung resistance (RL), exhalation resistance (RE)and lung dynamic compliance (Cdyn) was detected by using a lung function analysis system. Histopathological changes (severity of alveolarization) of the offspring rats' lung tissue were observed under microscope after H．E. stain., Results: Compared with the normal group, the PIF, RL and RE values were significantly increased ( P <0.01), and PEF and Cdyn values significantly decreased in the model group ( P <0.01). The alveolar diameter in the model group was evidently increased relevant to the normal group ( P <0.01). Following the intervention, modeling induced increase of PIF, RL, RE and alveolar diameter and decrease of PEF and Cdyn values in the EA-ST36 group, and the increased PIF, RL and RE levels in the EA-LU5 group were obviously suppressed relevant to the model group ( P <0.01, P <0.05). Additionally, modeling induced obvious congestion and edema of the alveolar wall, alveolar deformation, rupture and fusion, and reduction of the number of the pulmonary alveoli were evidently milder in both EA-ST36 and EA-LU5 groups. No significant differences were found between the EA-ST36 and EA-LU5 groups in the abovementioned 5 indexes of pulmonary function and alveolar diameter ( P >0.05)．., Conclusion: EA of ST36 and LU5 of mother rats experiencing nicotine exposure during pregnancy and lactation can improve the lung function and morphological changes in neonatal rats, and the effect of ST36 is relatively better.

Objective: To study the association of cytoplasmic phospholipase A2 (PLA2G4) rs932476 polymorphism with the development of bronchial asthma and the response to montelukast, a leukotriene receptor antagonist, in children., Methods: A total of 128 children with bronchial asthma were enrolled as case group, and 100 healthy children were enrolled as control group. The genotype and allele frequencies of PLA2G4 rs932476 were compared between the two groups. The children in the case group were administered with montelukast except routine treatment for 2 months, and the changes in serum levels of leukotriene B4 (LTB4), interleukin-4 (IL-4), immunoglobulin E (IgE), and interferon gamma (IFN-γ), pulmonary function and fractional exhaled nitric oxide (FeNO) after treatment were observed., Results: There were no significant differences in the genotype and allele frequencies of PLA2G4 rs932476 between the case and control groups, as well as between the groups with different severities of asthma (P>0.05). After treatment, the children with AA genotype had a significantly higher overall response rate than those with GG genotype. After treatment, the case group had significant reductions in the serum levels of IgE and IL-4 and a significant increase in the level of IFN-γ (P<0.05). After treatment, the children with GG genotype had a higher serum level of IL-4 and a lower level of IFN-γ than those with AA genotype. After treatment, the case group had significant increases in pulmonary function parameters, and the children with AA genotype had significantly higher parameters than those with GG genotype. The case group had a significant reduction in the level of FeNO, and the children with AA genotype had a significantly lower level than those with GG genotype after treatment. The case group had a significantly higher serum level of LTB4 than the control group before treatment (P<0.05). After treatment the case group had a significant reduction in the serum level of LTB4 (P<0.05). The children with GG genotype had a significantly higher level of LTB4 than those with AA genotype after treatment (P<0.05)., Conclusions: PLA2G4 rs932476 polymorphism is not associated with the susceptibility and severity of bronchial asthma in children, but it may has certain influence on children's response to the leukotriene receptor antagonist montelukast, possibly by affecting the level of LTB4.

Objective: To investigate the value of simultaneous amplification and testing (SAT) in the early diagnosis of Mycoplasma pneumoniae pneumonia (MPP) in children and related influencing factors., Methods: A total of 526 children with community-acquired pneumonia who were hospitalized between December 2016 and December 2017 were enrolled. Particle agglutination was used to measure serum Mycoplasma pneumoniae (MP) antibody (MP-Ab). The value of SAT in the diagnosis of MPP was evaluated based on these results., Results: Based on the results of serum MP-Ab measurement, 165 children were diagnosed with MPP. MP-SAT had a sensitivity of 90.9% (150/165), a specificity of 97.9% (368/376), and high accuracy (Youden index=0.89) in the diagnosis of MPP, suggesting that there was good consistency between these two methods (Kappa=0.90). The diagnostic sensitivity of MP-SAT in children with a short course of disease was significantly higher than that in children with a long course of disease (P=0.031). The diagnostic sensitivity of MP-SAT was significantly higher than that of single serum MP-Ab measurement (P=0.018), with poor consistency between these two methods (Kappa=0.039). MP-SAT had good consistency with double serum MP-Ab measurement (Kappa=0.91). The multivariate logistic regression analysis showed that course of disease (≥7 days) and out-of-hospital macrolide treatment were the main factors influencing the results of MP-SAT (P<0.05)., Conclusions: MP-SAT has high value in the early diagnosis of MPP and can effectively cover the shortage of single serum MP-Ab test in the acute stage and thus provide help for early clinical diagnosis. MP-SAT test should be performed in the early stage of the disease (<7 days) and before the application of macrolide treatment.

Objective: Current non-invasive early detection of colorectal cancer (CRC) requires improvement. We aimed to identified a fecal Clostridium symbiosum-based biomarker for early and advanced colorectal cancer detection., Design: In the test stage, the relative abundance of Clostridium symbiosum (C. symbiosum) was measured by qPCR in 781 cases including 242 controls, 212 colorectal adenoma (CRA) patients, 109 early CRC (tumor restricted to the submucosa) patients, 218 advanced CRC patients. The prediction accuracy was compared to Fusobacterium nucleatum (F. nucleatum), fecal immunochemical test (FIT) and CEA (carcinoembryonic antigen) and validated in an independent cohort of 256 subjects. Current status of the trial:ongoing/still enrolling. Primary endpoint:June, 2017 (Clinicaltrials.gov Identifier NCT02845973)., Results: Significant stepwise increase of C. symbiosum abundance was found in CRA, early CRC and advanced CRC (P<0.01). C. symbiosum outperformed all the other markers in early CRC prediction performance. The combination of C. symbiosum and FIT achieved better performance (0.803 for test cohort and 0.707 for validation cohort). For overall discrimination of CRCs, the combination of all above markers achieved the performance of 0.876., Conclusions: Fecal C. symbiosum is a promising biomarker for early and noninvasive detection of colorectal cancer, being more effective than F. nucleatum, FIT and CEA. Combining C. symbiosum and FIT or CEA may improve the diagnosis power., (Copyright © 2017. Published by Elsevier B.V.)

Objective: To observe the effect of low-frequency or high-frequency electroacupuncture (EA) stimulation of "Neiguan" (PC 6) on changes of skin blood perfusion volume of heart-related and heart-irrelevant acupoints in rats with normal or ischemic myocardium., Methods: Wistar rats were randomly divided into the control, sham-operation, model, low-frequency EA and high-frequency EA groups ( n =8 in each group). The myocardial ischemic (MI) model was established by occlusion of the anterior descending branch of the left coronary artery. 2 Hz and 100 Hz EA was respectively applied to left PC 6 for 20 min, once daily, a total of three times. Electrocardiogram (ECG) was recorded after the last treatment. Serum cardiac troponin T (cTnT) contents were assayed by ELISA. The skin blood perfusion volumes of bilateral PC 6, "Zusanli" (ST 36) and "Yanglingquan" (GB 34) were observed by laser speckle contrast imaging., Results: In comparison with the control and sham-operation groups, the differences of "J point" and contents of serum cTnT were significantly increased in the model group ( P <0.01). After EA, the differences of "J point" and contents of serum cTnT were significantly decreased in both low-frequency and high-frequency EA groups ( P <0.01, P <0.05). Compared with the control group, the skin blood perfusion volumes of bilateral PC 6 and ST 36 decreased obviously in rats of the model group ( P <0.01). After EA, the skin blood perfusion volumes were markedly up-regulated in the areas of PC 6 and ST 36 ( P <0.01). There were no significant changes in that of GB 34 among the 5 groups ( P <0.05)., Conclusions: Skin blood perfusion volumes around PC 6 and ST 36 can specifically reflect the change of the myocardial state.