Involvement of the ABA-and H_(2)O_(2)-Mediated Ascorbate-Glutathione Cycle in the Drought Stress Responses of Wheat Roots

Abscisic acid(ABA),hydrogen peroxide(H_(2)O_(2)) and ascorbate(AsA)–glutathione(GSH)cycle are widely known for their participation in various stresses.However,the relationship between ABA and H_(2)O_(2) levels and the AsA–GSH cycle under drought stress in wheat has not been studied.In this study,a hydroponic experiment was conducted in wheat seedlings subjected to 15%polyethylene glycol(PEG)6000–induced dehydration.Drought stress caused the rapid accumulation of endogenous ABA and H_(2)O_(2) and significantly decreased the number of root tips compared with the control.The application of ABA significantly increased the number of root tips,whereas the application of H_(2)O_(2) markedly reduced the number of root tips,compared with that under 15%PEG-6000.In addition,drought stress markedly increased the DHA,GSH and GSSG levels,but decreased the AsA levels,AsA/DHA and GSH/GSSG ratios compared with those in the control.The activities of the four enzymes in the AsA–GSH cycle were also markedly increased under drought stress,including glutathione reductase(GR),ascorbate peroxidase(APX),monodehydroascorbate reductase(MDHAR)and dehydroascorbate reductase(DHAR),compared with those in the control.However,the application of an ABA inhibitor significantly inhibited GR,DHAR and APX activities,whereas the application of an H_(2)O_(2) inhibitor significantly inhibited DHAR and MDHAR activities.Furthermore,the application of ABA inhibitor significantly promoted the increases of H_(2)O_(2) and the application of H_(2)O_(2) inhibitor significantly blocked the increases of ABA,compared with those under 15% PEG-6000.Taken together,the results indicated that ABA and H_(2)O_(2) probably interact under drought stress in wheat;and both of them can mediate drought stress by modulating the enzymes in AsA–GSH cycle,where ABA acts as the main regulator of GR,DHAR,and APX activities,and H_(2)O_(2) acts as the main regulator of DHAR and MDHAR activities.

Species composition and influencing factors of understory woody species in Robinia pseudoacacia plantations on the Loess Plateau

Black locust(Robinia pseudoacacia L.)plantations have contributed significantly to soil and water conservation and ecological reconstruction on China’s Loess Plateau.Understanding the impact of stand and environment on species composition of understory woody plants will improve the stability of existing black locust plantations.Ten stands were selected in second-generation black locust plantations in tableland and gully areas of the Loess Plateau.The number of understory tree species in the tablelands was significantly lower than in the gully stands.Regenerated black locust(19.76%)and Rubus corchorifolius L.f.(64.85%)were the most abundant understory tree and shrub species,respectively,in the tableland stands;Broussonetia papyrifera(L.)L’Hér.ex Vent.(6.77%)and Acanthopanax senticosus(Rupr.Maxim.)Harms.(37.22%)were most abundant in the gully stands.Species richness(S),Shannon diversity(H),and evenness index(J)of the understory plants were significantly lower in the tableland stands than in the gully stands.More diverse understory species and community structures occurred in the gully stands.Differences in species diversity among landform positions may be attributed to differences in soil moisture.In addition,77.57%of the variation in understory species composition was explained,among which shrub and herb coverage,stand age,leaf area index,slope and total soil phosphorus in the 10-20 cm layer were the main factors.Soil organic carbon and total potassium significantly impacted S,H and J.Considering the environmental conditions and the biological characteristics of the plants investigated,R.corchorifolius should be given priority in the development of tableland stands,while B.papyrifera and Celtis sinensis Pers.should form mixed forests with black locust in gully stands.This management could promote biodiversity and stability of the existing black locust plantations but also optimize regional landscape patterns.

Deep-ultraviolet photonics for the disinfection of SARS-CoV-2 and its variants(Delta and Omicron)in the cryogenic environment

Deep-ultraviolet(DUV)disinfection technology provides an expeditious and efficient way to suppress the transmission of coronavirus disease 2019(COVID-19).However,the influences of viral variants(Delta and Omicron)and low temperatures on the DUV virucidal efficacy are still unknown.Here,we developed a reliable and uniform planar light source comprised of 275-nm light-emitting diodes(LEDs)to investigate the effects of these two unknown factors and delineated the principle behind different disinfection performances.We found the lethal effect of DUV at the same radiation dose was reduced by the cryogenic environment,and a negative-U large-relaxation model was used to explain the difference in view of the photoelectronic nature.The chances were higher in the cryogenic environment for the capture of excited electrons within active genetic molecules back to the initial photo-ionised positions.Additionally,the variant of Omicron required a significantly higher DUV dose to achieve the same virucidal efficacy,and this was thanks to the genetic and proteinic characteristics of the Omicron.The findings in this study are important for human society using DUV disinfection in cold conditions(e.g.,the food cold chain logistics and the open air in winter),and the relevant DUV disinfection suggestion against COVID-19 is provided.

侦查辨认中存在的问题及预防措施

在侦查阶段,有效的辨认能够帮助侦查人员查明案件事实真相。侦查中,错误辨认现象时有发生,警察的不当行为是造成辨认错误的主要原因之一。另外,裁判者的错误信念也使得人们对于辨认结果具有极大的依赖性。本文认为在侦查辨认中,设置规范的程序以及允许律师在场,能够排除警察的不当行为,增加辨认的有效性。

The Relationship between Viral Replication and the Severity of Hepatic Necroinflammatory Damage Changed before HBeAg Loss in Patients with Chronic Hepatitis B Virus Infection

Background and Aims:Disease progression of chronic hepatitis B virus(HBV)infection is driven by the interactions between viral replication and the host immune response against the infection.This study aimed to clarify the relationship between HBV replication and hepatic inflammation during disease progression.Methods:Two cross-sectional,one validation cohort,and meta-analyses were used to explore the relationship between HBV replication and liver inflammation.Spearman analysis,multiple linear regression,and logistic regression were used to explore the relationship between variables.Results:In the cross-sectional cohorts A and B including 1,350 chronic hepatitis B patients,Spearman analysis revealed a negative relationship between HBV replication(such as HBV DNA)and liver inflammation(such as ALT)in HBeAg-positive patients with higher HBV DNA>2×10^(6) IU/mL(rho=0.278 and 0.260)and HBeAg-negative patients(rho=0.450 and 0.363).After adjustment for sex,age,and anti-HBe,results from logistic regression and multiple linear regression showed the opposite relationship still existed in HBeAg-positive patients with different DNA levels;the opposite relationship in HBeAg-positive patients with different DNA levels was validated in a third cohort;the opposite relationship in patients with different HBeAg status was partially confirmed by meta-analysis(overall R:-0.004 vs 0.481).Conclusions:These results suggested a negative relationship between viral replication and liver inflammation in HBeAgpositive patients with high HBV DNA,which changed to a positive relationship for those HBeAg-positive patients with DNA less than 2×10^(6) IU/mL and HBeAg-negative patients.

神经内镜辅助显微镜切除颅咽管瘤的临床研究

目的探讨神经内镜辅助显微镜技术在颅咽管瘤手术中的作用和价值。方法回顾性收集胜利油田中心医院神经外科和头颈血管外科自2015年1月至2017年11月收治的42例行神经内镜辅助显微镜切除的颅咽管瘤患者作为神经内镜辅助组,收集自2013年1月至2014年12月收治的45例行单纯经显微镜切除的颅咽管瘤患者作为单纯显微镜组,通过对2组患者的肿瘤切除率、术后并发症发生率及术后复发率进行比较,从而评价手术效果。结果神经内镜辅助组的肿瘤全切除率97.62%,术后血管痉挛发生率7.14%;单纯显微镜组的肿瘤全切除率80.00%,术后血管痉挛发生率22.22%,2组比较差异均具有统计学意义(P<0.05)。2组患者的术中垂体柄保留率、术后并发症(颅神经损伤、电解质紊乱、脑脊液漏、腺垂体功能减退、尿崩、颅内感染、死亡)发生率及术后复发率比较,差异均无统计学意义(P>0.05)。结论神经内镜辅助显微镜切除颅咽管瘤既能提高肿瘤全切除率又能降低并发症发生率,提高手术疗效。

Interleukin 17-Producing γδ T Cells Increased in Patients with Active Pulmonary Tuberculosis

Although it has been known that γδ T cells may play an important role in the immune response to infection of Mycobacterium tuberculosis （M. tb）, the mechanisms by which the γδ T cells participate in the innate and/or acquired immunity to tuberculosis （TB） have not been full elucidated. In the present study, 27 patients with active pulmonary TB and 16 healthy donors （HD） were performed. We found that proportion of IL-17-producing cells among lymphocyte was similar between TB patients and HD, whereas the proportions of γδ T cells in IL-17-producing cells （59.2%） and IL-17-producing cells in γδ T cells （19.4%） in peripheral blood were markedly increased in TB patients when compared to those in HD （43.9% and 7.7%, respectively）. In addition, the proportions of IFN-T-producing γδ T cells in TB patients were obviously lower than that in HD. Upon re-stimulated with M. tb heat-treated antigen （M. tb-HAg） in vitro, fewer IL-17-producing γδ T cells were generated from HD and TB patients, whereas IFN-T-producing γδ T cells were increased in TB patients compared to that in HD. Our findings in TB patients and healthy human were consistent with other murine investigation that the IL-17- producing γδ T cells were main source of IL-17 in mouse model of BCG infection, suggesting that γδ T cells might be involved in the formation of tubercular granuloma in pulmonary TB patients, but need further identification.

Desertification: China provides a solution to a global challenge

Desertification has been caused by various factors and is a major environmental problem and development bottleneck faced by the world. It is also a serious threat to ecological security and to sustainable economic and social development. As a stubborn world problem, focused on by the United Nations 2030 sustainable development goal 15.3, China aims to combat desertification by implementing the "eight-column fourbeam" strategy, and also suggest the "four-medicine"approach for global desertification governance. This includes the development of the United Nations Convention to Combat Desertification protocol, unified global compliance and compliance metrics; building a global observation network, and monitoring land changes based on remote sense; preparing the global natural desert(heritage) list, leaving the original deserts for future generations; initiating the global action of combating desertification, and striving to achieve a land degradationneutral world by 2030.

Potential dual outbreak of COVID-19 and HFMD among children in Asia-Pacific countries in the HFMD-endemic area

In the era of the pandemic of coronavirus disease 2019(COVID-19),the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infects infants and children with mild or atypical symptoms[1,2].The new variations in SARS-CoV-2 recently found in the United Kingdom greatly increased the risk of infection among children[3].Although previous evidence showed that children rarely developed severe symptoms from COVID-19,the hospitalization rate was 24.5%and the ICU admission rate was 2.5%among children in the United States[4].Further,there is a lack of evidence regarding the influence of the recently appeared SARS-CoV-2 variations.Thus,it is of great significance to monitor and track the COVID-19 infection among children.

Similar aerosol emission rates and viral loads in upper respiratory tracts for COVID-19 patients with Delta and Omicron variant infection

Dear Editor,In 2021,the Delta variant of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)caused the coronavirus disease 2019(COVID-19)pandemic to spread in the UK,Nepal,southeast Asia and elsewhere,which seems to be approximately 60%more transmissible than the already highly infectious Alpha variant in late 2020(Callaway,2021).In addition to the high efficiency of the invading infection and the acquired immune escape ability,changes in the aerodynamic characteristics of SARS-CoV-2 aerosols may be another important reason for the Delta variant spread.Previously,it was identified that SARS-CoV-2 can spread through close contact and airborne routes(Guo et al.,2020;Morawska and Milton,2020).

PIKfyve inhibitors against SARS-CoV-2 and its variants including Omicron

Dear Editor,COVID-19 pandemic,caused by SARS-CoV-2 infection,is raging around the world and results in millions of deaths since the end of 2019.Although various therapies including vaccines and neutralizing antibodies have been developed to defend against the horrible pandemic,current strategies are inevitably at risk of failure due to high mutagenicity of the viral genome.In fact,the most worrying situation is that the monoclonal antibodies of existing vaccines against the rapidly spreading Omicron variant are ineffective.