[Tillage Depth Regulation and the Effect of Straw Return on Soil Respiration in Farmland]

Straw return and tillage depth treatments are one of the most important agricultural management measures that affect farmland soil respiration, but the mechanism of their interaction affecting farmland soil respiration remains unclear. Therefore, 116 published research articles were used through Meta-analysis technology for dryland farmland ecosystems in China to explore the effects of straw return and tillage depth treatments and their interaction on farmland soil respiration and its regulatory factors, which will provide important data support and a theoretical basis for achieving "carbon neutrality" in farmland ecosystems. The results showed that no tillage reduced soil respiration by 8.3%, and the effects of shallow and deep tillage treatments on soil respiration were not significant, but the increase in soil respiration still showed a trend of deep tillage>shallow tillage>no tillage. However, both shallow and deep tillage had relatively small effects on soil respiration and soil organic carbon (SOC), whereas no tillage reduced soil respiration by 8.3% and increased SOC by 7.05%. Therefore, implementing no tillage measures is of great significance for soil carbon sequestration and emission reduction in farmland ecosystems. In addition, tillage depth significantly regulated the impact of straw return on soil respiration, and the increase in soil respiration showed a trend of deep tillage straw return>shallow tillage straw return>no tillage straw return, with an overall average increase of 14.51%. The increase in soil respiration under different tillage depth treatments after straw return was closely related to the change in soil bulk density, crop yield, SOC, soil temperature, and moisture, and the contribution to the increase in soil respiration showed a trend of soil bulk density>crop yield>soil organic carbon>soil moisture>soil temperature. However, SOC increased by 29.32%, 10.12%, and 23.94%, respectively, in the deep tillage straw return, shallow tillage straw return, and no tillage straw return treatments, whereas soil respiration increased by 29.32% and 18.92%, respectively, in the deep tillage straw return and shallow tillage straw return treatments, and it only increased by 1.2% in the no tillage straw return treatment. Therefore, no tillage straw return was also beneficial to soil carbon sequestration and emission reduction in farmland ecosystems. Thus, in the dryland farmland ecosystem of China, tillage depth treatments regulated the impact of straw return on soil respiration, which was mainly related to soil physical and chemical properties, especially being closely related to soil bulk density. Moreover, no tillage and no tillage straw return are important agricultural management measures that are conducive to soil carbon sequestration and emission reduction.

[Association of high-density lipoprotein cholesterol with risk of cardiovascular disease mortality]

Objective: To analyze the association between high density lipoprotein cholesterol (HDL-C) and the risk of cardiovascular disease mortality. Methods: A total of 71 618 residents aged over 18 years with complete baseline data, who were filed on the health information big data platform of Yinzhou district, Ningbo city, Zhejiang Province from 2009 to 2014, were selected as the research population. The research population were divided into four groups according to the level of HDL-C: low-level group (HDL-C<1.0 mmol/L), intermediate-level group (1.0 mmol/L≤HDL-C<1.5 mmol/L), medium-high-level group (1.5 mmol/L≤HDL-C<2.0 mmol/L) and high-level group (HDL-C≥2.0 mmol/L). Cox proportional hazard model was used to calculate the risk ratio of cardiovascular diseases mortality in different groups. Results: The study population was followed up for a total of 427 989.4 person-years, follow-up time of (5.98±1.04)years. During the follow-up period, there were 799 deaths due to cardiovascular diseases. After adjusting for confounding factors, compared with the medium-high-level group as the reference group, the HR (95%CI) for cardiovascular diseases mortality was 1.43 (1.13-1.82) in the low-level group and 1.22 (1.02-1.46) in the high-level group. Conclusion: The low level of HDL-C (<1.5 mmol/L) is associated with a higher risk of cardiovascular disease deaths. The level of HDL-C can be used as a biological indicator to monitor the development of cardiovascular diseases and guide treatment.

Experiences of healthcare providers during the coronavirus pandemic and its impact on them: protocol for a mixed-methods systematic review

INTRODUCTION

Frontline healthcare providers are redeployed to areas outside their clinical expertise and assigned high-loading workload to address the surge of patients with each coronavirus outbreak. Their importance in crisis is not in doubt. However, they experienced considerable physical distress and psychological stressors, even leading to psychological illness and infection in this environment. There is an urgent need to accurately, comprehensively and objectively understand their experiences, perceptions and current situation of burnout, post-traumatic stress disorder (PTSD), anxiety, depression, insomnia and coronavirus infection. Therefore, this protocol is to conduct a mixed-methods systematic review to summarise the evidence on the experiences of healthcare providers and impacts of the coronavirus on their psychological status and infection during the pandemics.

METHODS

Published studies on experience, perspective, impact, burnout, PTSD, anxiety, depression, insomnia, and infection of healthcare providers with SARS, Middle East respiratory syndrome and COVID-19, and written in English and Chinese will be accepted. Databases (MEDLINE, EMBASE, CENTRAL, Web of Science, PubMed, Psychology Information, WanFang and SinoMed) from inception until 30 July 2020 will be searched. Two reviewers will select, screen, extract data and assess the risk of bias independently. Risk of bias of results will be using the Mixed-Methods Appraisal Tool. Using a convergent integrated approach on qualitative/quantitative studies, we will synthesise qualitative and quantitative data separately. The incidence and number of cases about burnout, PTSD, anxiety, depression, insomnia and coronavirus infection among medical staff will be extracted. Then we will transform quantitative data to synthesise narrative findings. This protocol will be reported per the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols guidelines.

ETHICS AND DISSEMINATION

Ethical assessment is not required due to the nature of the proposed systematic review. Findings of our research will be disseminated at conferences related to this field and through publication in peer-reviewed journals.

PROSPERO REGISTRATION NUMBER

CRD42020198506.

[Application and analysis of abdominal aortic branch malperfusion pattern in thoracic endovascular aortic repair for Stanford B aortic dissection]

OBJECTIVE

To evaluate the efficiency of thoracic endovascular aortic repair (TEVAR) in dealing with abdominal aortic branch malperfusion based on the analysis of aortic computed tomography angiography (CTA) images in pre- and post-TEVAR.

METHODS

Retrospective analysis from September 2015 to March 2016 in single institution to 32 patients, diagnosed as Stanford B aortic dissection with abdominal aortic branch malperfusion, CTA images in pre- and post-TEVAR were collected. Based on the aortic branch malperfusion pattern redefined by Nagamine, we identified and characterized branch malperfusion pattern for four abdominal aortic branches (celiac trunk, superior mesenteric artery, bilateral renal artery) in statistical analysis.

RESULTS

In the four abdominal aortic branches (total 128 branches), 86 branches (67.2%) expressed with Class I patterns, in which subtype I-b presented with 0.8%, subtype I-c with 5.5%; 14 branches (10.9%) expressed with Class II patterns, in which subtype II-b-1 with 3.9%, subtype II-b-2 with 3.1%; 16 branches (12.5%) expressed with Class III patterns, all with subtype III-a, no subtype III-b and III-c presented. The remaining 12 branches were normal. The 100% successful rate of TEVAR obtained in 32 patients performed. The mean following-up was 4 months. Aortic CTA showed that among the 14 "high-risk" abdominal aortic branch malperfusion, 13 (92.9%) with obvious branch malperfusion in post-TEVAR were observed to improve, and the remaining one branch malperfusion (7.1%) was observed to change from subtype I-b to I-c.

CONCLUSION

Few ratios in abdominal aortic branches suffered with obvious malperfusion complicated by Stanford B aortic dissection. For branches with "high-risk" malperfusion pattern, optimal changes were observed in abdominal aortic branch without revascularization in post-TEVAR, as well other branches with non-"high-risk" pattern perfusion were mostly stable in post-TEVAR. It could be of profound benefit to extend branch malperfusion patterns redefined by Nagamine in clinical practice to assess aortic dissection and in further guide for revascularization or not.

[Acute toxicity and bio-distribution of silver nitrate and nano-silver with different particle diameters in rats]

Objective: To explore the acute toxic effect and the cumulative target organ of silver nitrate and nano-silver with two different particle diameters in rats. Methods: Thirty-six adult SD rats were divided into small particle size nano-silver group (SNS), large particle size nano-silver group (LNS), silver nitrate group (SN), and control group (C) according to the random number table, with 9 rats in each group. The rats of the four groups were respectively injected with 10 mg/mL nano-silver solution (particle diameter of 20 nm, prepared by saline) in silver dose of 30 mg/kg by tail vein for once, 10 mg/mL nano-silver solution (particle diameter of 100 nm, prepared by saline) in silver dose of 30 mg/kg, 1.67 mg/mL silver nitrate solution (prepared by glucose solution) in silver dose of 3 mg/kg, and 30 mg/mL polyvinylpyrrolidone solution (prepared by saline) in dose of 90 mg/kg. (1) Toxicity test. The general observation was performed within 14 days after injection, and the deviation between value of body mass before injection and each of that on post injection day (PID) 1, 7, and 14 were respectively recorded. On PID 1, 7, and 14, 3 rats of each group were harvested for determination of serum content of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total protein, and albumin by fully automatic biochemical analyzer. Then the rats were sacrificed immediately, and heart tissue, liver tissue, spleen tissue, lung tissue, kidney tissue, and brain tissue were collected to calculate the organ coefficient. Organ samples with obvious changes in organ coefficient were collected for histopathological observation by HE staining, with 3 samples in each group at each time point. (2) Bio-distribution. The specimens of heart, liver, spleen, lung, and kidney of rats from groups SNS, LNS, and SN were collected for detection of silver content by inductively coupled plasma mass spectrometry, with 3 samples in each group at each time point. Data were processed with analysis of variance of factorial design, LSD test, and Dunnett's T3 test. Results: (1) The general condition of rats in groups C and SN after injection were normal. The state of rats of groups SNS and LNS was poor with black secretion in the eye and other phenomena on PID 1, which recovered from PID 3 on. (2) The deviations between values of body mass before injection and that on PID 14 in rats of groups LNS and SN were significantly decreased as compared with deviation of group C (with P values below 0.01), but deviation of group SNS was not significantly changed (P>0.05). The deviations between values of body mass before injection and each of that on PID 1 and 7 in rats in the other three groups were similar to those in group C (with P values above 0.05). (3) Compared with those in group C, the serum content of total protein of rats in group SN on PID 1 was significantly decreased, and liver coefficient was significantly increased (with P values below 0.05). On PID 1, the serum content of ALT of rats in group LNS was (61.0±8.7) U/L, which was significantly higher than that in group C [(40.0±4.6) U/L, P<0.01]. Compared with those in group C [(126.0±3.5) U/L and 4.05±0.23], the serum content of AST of rats in groups SNS and LNS on PID 1[(249.7±107.2) and (237.0±38.3) U/L] was significantly increased, and liver coefficients (3.50±0.38 and 3.31±0.07) were significantly decreased, with P values below 0.05. Compared with those in group C [(69.2±4.8) U/L and 4.32±0.39], the serum content of AST of rats in groups SNS and LNS on PID 7 [(181.0±51.5) and (167.7±16.5) U/L] was also significantly increased, and liver coefficients (3.55±0.18 and 3.62±0.21) were also significantly decreased, P<0.05 or P<0.01. On PID 14, the four liver biochemical indexes in serum and all organ coefficients of rats in the other three groups were similar to those in group C (with P values above 0.05). (4) The liver of rats in group SN had slight degeneration on PID 1, the liver cells around the central vein of liver of rats in group SNS had slight degeneration on PID 7, and the liver cells got severely eosinophilic degeneration in liver of rats in group LNS on PID 7. There was no significant pathological change in the liver of rats in each group at the rest time points. (5) The silver content of lung and kidney in rats of group SNS on PID 1, that of spleen and kidney in rats of group LNS on PID 1, and that of heart and kidney in rats of groups LNS and SNS on PID 7 was significantly less than that of group SN (with P values below 0.05). The silver content of liver and spleen in rats of group SNS on PID 14 was significantly more than that of group SN (with P values below 0.05). Compared with that of group SN, the silver content of lung on PID 1 and liver on PID 7 in rats of group LNS was significantly increased (with P values below 0.05). On PID 14, there was no significant change in the silver content of all organs of rats between group SN and group LNS (with P values above 0.05). The silver content of heart, lung, and kidney on PID 1 and heart on PID 7 in rats of group LNS was significantly more than that of group SNS (with P values below 0.05). On PID 14, the silver content of each organ of rats in group SNS was close to that in group LNS (with P values above 0.05). Conclusions: Silver nitrate and nano-silver with two different particle diameters have a short acute toxic effect on the liver of rats, and the liver has certain ability of self-healing. Nano-silver is mainly accumulated in the liver. The distribution of nano-silver with large particle diameter in organs is more widely than that of nano-silver with small particle diameter.

Low-concentration capsaicin promotes colorectal cancer metastasis by triggering ROS production and modulating Akt/mTOR and STAT-3 pathways

Colorectal cancer (CRC), one of the most common human malignancies, is a major public health problem in the developed world. Capsaicin, widely used as a food additive and as an analgesic agent, is a major pungent ingredient of red pepper. Though capsaicin-induced apoptosis was previously reported in cancer cells, relatively little is known about the impact of capsaicin on other aspect of cancer cell behavior. In this study, we demonstrated that treatment with high-concentration of capsaicin (≥ 200 µM for SW480 and CT-26 cell lines; ≥ 25 µM for HCT116 cell line) inhibited CRC cell proliferation in a dose-dependent manner. In spite of no anti-proliferative effect, notably, low-concentration of capsaicin (100 µM for SW480 and CT-26 cell lines; 12.5 µM for HCT116 cell line) enhanced both migratory and invasive capability of these cells, which was validated by both in vitro and in vivo model. Further, we showed that 100 µM capsaicin induced epithelial-to-mesenchymal (EMT), up-regulated expression of MMP-2 and MMP-9, and activated Akt/mTOR and STAT-3 pathways in SW480 cells. Finally, we showed that capsaicin-induced metastasis of CRC cells was mediated by modulating reactive oxygen species (ROS) production. Our findings are considered a significant step toward a better understanding of capsaicin-associated regulatory network on CRC cells.

HNF1 and/or HNF3 may contribute to the tissue specific expression of glucokinase gene

A possible role of hepatocyte nuclear factor 1 (HNF1) or HNF3, a predominant trans-acting factors of hepatic or pancreatic beta-cells, was examined on the tissue specific interdependent expression of glucokinase (GK) in liver, H4IIE, HepG2, HIT-T15 and MIN6 cell line. The tissues or cell lines known to express GK showed abundant levels of HNF1 and HNF3 mRNA as observed in liver, H4IIE, HepG2, HIT-T15 and MIN6 cells, whereas they were not detected in brain, heart, NIH 3T3, HeLa cells. The promoter of glucokinase contains several HNF3 consensus sequences and are well conserved in human, mouse and rat. Transfection of the glucokinase promotor linked with luciferase reporter to liver or pancreatic beta cell lines showed high interacting activities with HNF1 and HNF3, whereas minimal activities were detected in the cells expressing very low levels of HNFs. The binding of HNF1 or HNF3 to the GK promoter genes was confirmed by electrophoretic mobility shift assay (EMSA). From these data, we propose that the expression of HNF1 and/or HNF3 may, in part, contribute to the tissue specific expression of GK

[Inhibitory effect of methanol extract of Boschniakia rossica Fedtsch. et Flerov on rat hepatic preneoplastic lesions induced by diethylnitrosamine]

OBJECTIVE

To investigate the inhibitory effect of Boschniakia rossica(BR) on hepatocarcinogenesis in rats.

METHOD

Based on immunohistochemistry techniques, the expression of placental form glutathione S-transferase(GST-P), mutant p53 and p21 protein were investigated in hepatic preneoplastic lesions induced by Solt-Farber protocol in the liver of rats that had been treated with the above method, administered with BR extract and of control group.

RESULT

The extract of BR(500 mg/kg) has inhibitory effect on the formation of diethylnitrosamine-induced GST-P-positive foci in F344 rat and the expression of mutant p53 and p21 protein was lower than that of hepatic preneoplastic lesions, and the increasing gamma-glutamyltranspeptidase(gamma-GT) activity in rat liver treated with Solt-Farber protocol was decreased by the extract of BR.

CONCLUSION

These results indicate that BR has inhibitory effect on DEN induced hepatic preneoplastic lesions in F344 rat.

p16INK4 and p15INK4B alterations in primary gynecologic malignancy

Chromosome 9 abnormalities have been found in primary tumors and cell lines from human gynecologic malignancy. Alterations of p16INK4 and p15INK4B genes mapped on the band p21 of chromosome 9 have been detected in various human tumors, but the role of these genes as tumor suppressors in vivo appear to be dependent on tumor type. Polymerase chain reaction (PCR)-based analysis was performed to search for lesions of these genes in 202 primary gynecologic malignancies. Homozygous deletions of p16INK4 were detected in 7 of 128 (5%) cervical, 1 of 41 (2%) endometrial, 2 of 27 (7%) ovarian, and 3 of 6 (50%) vulvar carcinomas, while homozygous deletions of p15INK4B were detected in 19 of 128 (15%) cervical, 1 of 41 (2%) endometrial, 9 of 27 (33%) ovarian, and 3 of 6 (50%) vulvar carcinomas, respectively. No mutations were found in exon 2 of p16INK4 from 161 cases of gynecologic malignancy without deletion of p16INK4. All 3 cases of vulvar carcinoma showing homozygous deletions of p16INK4 and p15INK4B were at advanced clinical stage (stage III-IV), while all 7 cases of cervical carcinoma and 2 cases of ovarian carcinoma showing homozygous deletion of p16INK4 were at early stage (stage I-II). The results indicate that homozygous deletions of p16INK4 and/or p15INK4B genes may play a role in a subset of primary gynecologic malignancy.

[The rapid effect of the iontophoretically applied cortisol on unit activity of neurons in three brain areas in rats]

The present study was undertaken to analyze whether the glucocorticoid (GC) effect was region specific in the brain. Na-cortisol-succinate (HC) was applied iontophoretically to cerebral cortex (CX), hippocampus (HPC) and PVN respectively and the effect on unit discharge rate in these three brain areas were compared. In cerebral cortex, the percentage of responsive neurons was only 8% (4/50), which was significantly lower than those in HPC (10/36, 27.8%) and PVN (9/35, 25.7%). The difference in the occurrence is paralleled with the known distribution of traditional GC cytosolic receptors in the brain. In all the three brain areas studied the main response to GC was inhibitory and the latencies of the responses were 9.6 +/- 6.5, 22.7 +/- 24.0, and 14.5 +/- 11.5 s and the durations of the after-effect were 74.8 +/- 66.5 (n = 4), 24.2 +/- 14.5 (n = 6) and 21.0 +/- 10.5 s (n = 9) respectively. The shortness of the latencies once again suggests that the mechanism involved is non-genomic. It is interest to note that in some HPC neurons the after-effect lasted for 1758 +/- 2148 s (n = 4). The results show that the rapid effect of GC on neurons is different in the three brain areas studied in regarding to the occurrence of responsive neurons and the duration of the after-effects.