Observation of Low-Level Jets in the Eastern Tropical Indian Ocean Based on Shipborne Coherent Doppler Lidar

In contrast to the Pacific and Atlantic Oceans,the Indian Ocean has lacked in-situ observations of wind profiles over open sea areas for decades.In 2021,a shipborne coherent Doppler lidar(CDL)was used to observe in-situ wind profiles in the eastern tropical Indian Ocean.This equipment successfully captured low-level jets(LLJs)in the region,and their characteristics were thoroughly analyzed.Results reveal that the observed wind speed of LLJs in the eastern Indian Ocean ranges from 6 m s^(-1) to 10 m s^(-1) during the boreal winter and spring seasons,showing a height range of 0.6 to 1 km and two peak times at 0800 and 2000 UTC.This wind shear is weaker than that in land or offshore areas,ranging from 0 s^(-1) to 0.006 s^(-1).Moreover,the accuracy of the CDL data is compared to that of ERA5 data in the study area.The results indicate that the zonal wind from ERA5 data significantly deviated from the CDL measurement data,and the overall ERA5 data are substantially weaker than the in-situ observations.Notably,ERA5 underestimates northwestward LLJs.

Low level of hepatitis B viremia is associated with increased risk of hepatocellular carcinoma in compensated cirrhotic patients

BACKGROUND Whether patients with compensated cirrhosis and low-level viremia(LLV)of hepatitis B should receive antiviral therapy(AVT)is still controversial,and published results are inconsistent.AIM To investigate the link between LLV in compensated cirrhosis and prognosis concerning hepatocellular carcinoma(HCC),decompensation,and liver-related events.METHODS The PubMed,EMBASE,and Cochrane Library databases were searched up to March 5,2023.Outcomes of interest were assessed by pooled hazard ratios(HRs).The study was registered with PROSPERO(CRD42023405345).RESULTS Six cohort studies representing 3155 patients were included.Compared with patients with undetectable HBV DNA,patients with LLV was associated with increased risk of HCC(HR:2.06,95%CI:1.36-3.13;Q-statistic-P=0.07,I^(2)=51%)regardless of receiving AVT or not(AVT group:HR:3.14;95%CI:1.73-5.69;Qstatistic-P=0.60,I2=0%;un-AVT group:HR:1.73,95%CI:1.09-2.76;Q-statistic-P=0.11,I2=50%).The pooled results showed no statistical association between LLV and decompensation of cirrhosis(HR:2.06,95%CI:0.89-4.76;Q-statistic-P=0.04,I2=69%),and liver-related events(HR:1.84,95%CI:0.92-3.67;Q-statistic-P=0.03,I2=72%),respectively.Grading of Recommendations Assessment,Development and Evaluation assessment indicated moderate certainty for HCC,very low certainty for decompensation of cirrhosis and liver-related clinical events.CONCLUSION LLV in compensated cirrhotic patients is associated with increased risk of HCC,higher tendency for hepatic decompensation and liver-related events.Closer screening of HCC should be conducted in this population.

Risk factors for very low-level viremia in patients with chronic hepatitis B virus infection: A single-center retrospective study

Background and aim:Several effective antiviral drugs are now available;however,the risk of liver-related complications is still present.Low-level viremia(LLV),defined as a hepatitis B virus(HBV)deoxy-ribonucleic acid(DNA)load lower than 2000 IU/mL,is one of the major factors responsible for these complications.It has been reported that 22.7e43.1%of patients with HBV experience LLV.Herein,we aimed to explore the risk factors for very LLV(VLLV)during antiviral treatment.Methods:We collected data of patients with chronic hepatitis B(CHB)who received nucleos(t)ide analog treatment from October 2016 to April 2021.VLLV was defined as an HBV DNA load of 9e20 IU/mL.A total of 139 patients with LLV were matched with 139 patients with a sustained virological response at a 1:1 ratio according to age and gender.Results:Seropositivity rates for hepatitis B e antigen(HBeAg)(45.3%vs.17.3%,P<0.001)and hepatitis B surface antigen(HBsAg,3.11±0.68 lg IU/mL vs.2.54±1.04 lg IU/mL,P<0.001)and alanine amino-transferase levels(30.34±15.08 U/L vs.26.15±16.66 U/L,P¼0.040)in the two groups were significantly different.The multivariate analysis showed that both HBeAg seropositivity(adjusted odd ratio(aOR),3.63;95% confidence interval(CI):1.98±6.64;P<0.001)and HBsAg levels(aOR,2.21;95% CI:1.53±3.20;P<0.001)are independent risk factors for VLLV.During the multivariate analysis in the subgroup of HBeAg-positive patients,male gender(aOR,3.68;95% CI:1.23±10.76;P=0.017)and high HBsAg(aOR,4.86;95%CI:1.73e13.64;P¼0.003)levels were significantly correlated with VLLV.However,this was not the case in HBeAg-negative patients(P>0.050).HBeAg seropositivity(aOR,5.08;95% CI:2.15±12.02;P<0.001 vs.aOR,2.78;95% CI:1.16±7.00;P=0.022)and HBsAg levels(aOR,2.75;95% CI:1.41e5.37;P=0.003 vs.aOR,2.10;95% CI:1.27±3.46;P=0.004)significantly increased the risk of VLLV,irrespective of the age group.Both HBsAg(area under the receiver operating characteristic curve(AUC),0.681;95% CI:0.623±0.736;P<0.001)and HBeAg(AUC,0.640;95% CI:0.581±0.697;P<0.001)had certain pre-dictive value for VLLV.Conclusion:HBeAg seropositivity and higher HBsAg levels were not only risk factors for VLLV but also predicted its occurrence.When a patient with CHB remains HBeAg seropositive with high HBsAg levels after antiviral treatment for 48 weeks,emphasis should be placed on the potential occurrence of VLLV,warranting the use of highly sensitive HBV DNA detection methods.

New therapeutic options for persistent low-level viremia in patients with chronic hepatitis B virus infection:Increase of entecavir dosage

Chronic hepatitis B virus(HBV)infection(CHB)is a public health concern worldwide.Current therapies utilizing nucleos(t)ide analogs(NA)have not resulted in a complete cure for CHB.Furthermore,patients on long-term NA treatment often develop low-level viremia(LLV).Persistent LLV,in addition to causing the progression of liver disease or hepatocellular carcinoma,may shed light on the current plight of NA therapy.Here,we review the literature on LLV,NA treatment,and various doses of entecavir to find a strategy for improving the efficacy of this antiviral agent.For LLV patients,three therapeutic options are available,switching to another antiviral monotherapy,interferon-αswitching therapy,and continuing monotherapy.In real-world clinical practice,entecavir overdose has been used in antiviral therapy for CHB patients with NA refractory and persistent LLV,which encouraged us to conduct further in-depth literature survey on dosage and duration related entecavir studies.The studies of pharmacodynamics and pharmacokinetics show that entecavir has the maximal selected index for safety,and has great potential in inhibiting HBV replication,in all of the NAs.In the particular section of the drug approval package published by the United States Food and Drug Administration,entecavir doses 2.5-20 mg/d do not increase adverse events,and entecavir doses higher than 1.0 mg/d might improve the antiviral efficacy.The literature survey led us to two suggestions:(1)Increasing entecavir dose to 1.0 mg/d for the treatment of NA naïve patients with HBV DNA>2×106 IU/mL is feasible and would provide better prognosis;and(2)Further research is needed to assess the long-term toxic effects of higher entecavir doses(2.5 and 5.0 mg/d),which may prove beneficial in treating patients with prior NA treatment,partial virological response,or LLV state.

The Roles of Low-level Jets in “21·7” Henan Extremely Persistent Heavy Rainfall Event

An extremely heavy rainfall event lasting from 17 to 22 July 2021 occurred in Henan Province of China, with accumulated precipitation of more than 1000 mm over a 6-day period that exceeded its mean annual precipitation. The present study examines the roles of persistent low-level jets(LLJs) in maintaining the precipitation using surface station observations and reanalysis datasets. The LLJs triggered strong ascending motions and carried moisture mainly from the outflow of Typhoon In-fa(2021). The varying directions of the LLJs well corresponded to the meridional shifts of the rainfall. The precipitation rate reached a maximum during 20-21 July as the LLJs strengthened and expanded vertically into double LLJs, including synoptic-weather-system-related LLJs(SLLJs) at 850–700 hPa and boundary-layer jets(BLJs)at ~950 hPa. The coupling of the SLLJ and BLJ provided strong mid-and low-level convergence on 20 July, whereas the SLLJ produced mid-level divergence at its entrance that coupled with low-level convergence at the terminus of the BLJ on21 July. The formation mechanisms of the two types of LLJs are further examined. The SLLJs and the low-pressure vortex(or inverted trough) varied synchronously as a whole and were affected by the southwestward movement of the WPSH in the rainiest period. The persistent large total pressure gradient force at low levels also maintained the strength of low-level geostrophic winds, thus sustaining the BLJs on the synoptic scale. The results based on a Du-Rotunno 1D model show that the Blackadar and Holton mechanisms jointly governed the BLJ dynamics on the diurnal scale.

A novel method for gamma spectrum analysis of low-level and intermediate-level radioactive waste

The uncertainty of nuclide libraries in the analysis of the gamma spectra of low-and intermediate-level radioactive waste(LILW)using existing methods produces unstable results.To address this problem,a novel spectral analysis method is proposed in this study.In this method,overlapping peaks are located using a continuous wavelet transform.An improved quadratic convolution method is proposed to calculate the widths of the peaks and establish a fourth-order filter model to estimate the Compton edge baseline with the overlapping peaks.Combined with the adaptive sensitive nonlinear iterative peak,this method can effectively subtracts the background.Finally,a function describing the peak shape as a filter is used to deconvolve the energy spectrum to achieve accurate qualitative and quantitative analyses of the nuclide without the aid of a nuclide library.Gamma spectrum acquisition experiments for standard point sources of Cs-137 and Eu-152,a segmented gamma scanning experiment for a 200 L standard drum,and a Monte Carlo simulation experiment for triple overlapping peaks using the closest energy of three typical LILW nuclides(Sb-125,Sb-124,and Cs-134)are conducted.The results of the experiments indicate that(1)the novel method and gamma vision(GV)with an accurate nuclide library have the same spectral analysis capability,and the peak area calculation error is less than 4%;(2)compared with the GV,the analysis results of the novel method are more stable;(3)the novel method can be applied to the activity measurement of LILW,and the error of the activity reconstruction at the equivalent radius is 2.4%;and(4)The proposed novel method can quantitatively analyze all nuclides in LILW without a nuclide library.This novel method can improve the accuracy and precision of LILW measurements,provide key technical support for the reasonable disposal of LILW,and ensure the safety of humans and the environment.

Axial length shortening in myopic children with Stickler syndrome after repeated low-level red-light therapy

AIM:To report the myopia-controlling effect of repeated low-level red-light(RLRL)therapy in patients with Stickler syndrome(STL),an inherited collagenic disease typically presenting with early onset myopia.METHODS:Three STL children,aged 3,7,and 11y,received RLRL therapy throughout the follow-up period of 17,3,and 6mo,respectively after exclusion of fundus anomalies.Data on best-corrected visual acuity(BCVA),intraocular pressure,cycloplegic subjective refraction,ocular biometrics,scanning laser ophthalmoscope,optical coherence tomography,genetic testing,systemic disease history,and family history were recorded.RESULTS:At the initiation of the RLRL therapy,the spherical equivalent(SE)of 6 eyes from 3 patients ranged from-3.75 to-20.38 D,axial length(AL)were from 23.88 to 30.68 mm,and BCVA were from 0.4 to 1.0(decimal notation).Myopia progression of all six eyes slowed down after RLRL therapy.AL in five out of the six eyes shortened-0.07 to-0.63 mm.No side effects were observed.CONCLUSION:Three cases of STL whose progression of myopic shift and AL elongation are successfully reduced and even reversed after RLRL therapy.

The Prevalence of Human Cytomegalovirus Viremia among HIV-1 Infected Individuals Undergoing Antiretroviral Therapy

HIV infection is an emerging health issue in Libya, particularly among young adults. Human cytomegalovirus (HCMV) is a prevalent infectious agent that presents with subclinical and fatal diseases in immunosuppressed individuals including HIV-infected individuals. Although the impact of HCMV infection in HIV-positive patients is well documented in several regions, epidemiologic estimates concerning HCMV co-infection among HIV-infected individuals remain limited in Libya. Hence, this cross-sectional study was undertaken to derive data regarding the prevalence of active HCMV viremia among HIV-infected individuals undergoing antiretroviral therapy (ART) from Libya. A total of 90 consented HIV-infected subjects followed by the National Center for Disease Control (NCDC) of Benghazi/Libya were recruited in this study and investigated for HCMV-IgG, HCMV-IgM specific antibodies, detection of HCMV lower matrix phosphoprotein (pp65) antigen, and detection of HCMV-DNA using qPCR to assess the prevalence of HCMV viremia. We determined that 77 (85.56%) of subjects were seropositive for HCMV-IgG antibodies, whereas the seropositivity for HCMV-IgM was 3.33% (3/90 subjects). Our results also revealed that 4.44% (4/90) of participants had viral antigenemia based on the laboratory diagnosis of HCMV-pp65. Regarding the PCR, we were able to detect the DNA of HCMV only in 3/90 subjects (3.33%) suggesting an active viremic condition. The detection of HCMV DNA along with the HCMV-pp65 in HIV-positive individuals highlights the necessity of early diagnosis to manage the progression of the disease. Furthermore, we highly recommend the use of anti-HCMV therapy in viremic individuals in combination with ART to reduce the burden of HCMV complications.

Formation of Low-Level Jets over Southern China in the Mei-yu Season

This study examines the diversity of low-level jet(LLJ)formation and related physical processes over southern China.A total of 171 LLJ formation events with enhanced daily southwesterlies and early-morning maximum wind speeds were observed during the mei-yu seasons of 1989–2018.The LLJs can be further categorized into four types based on the increases in the daily mean and diurnal amplitude of the low-level winds.Analysis of the synoptic-scale disturbances shows that the two types of LLJ formation(Q1 and Q4),which feature large increases of daily southerly wind components,are mainly induced by west-east dipole patterns of pressure change,in association with the enhanced southwest vortex and/or the western Pacific subtropical high(WPSH).In contrast,the other two types(Q2 and Q3),which feature relatively large increases in their daily westerly components,are related to a northwest-southeast dipole pattern of pressure change due to the mid-latitude trough and the WPSH.We further analyze the considerable variations in the diurnal thermal forcing among the LLJ formation events.The strong(weak)daytime heating of solar radiation leads to relatively large(small)increases in the diurnal amplitude of low-level winds in Q1 and Q2(Q3 and Q4)types.Therefore,different combinations of synopticscale disturbances and diurnal thermal forcings are found to account for the diversity in LLJ formation and associated differences in downstream rainfall patterns.These results help to improve our understanding and prediction of the formation of LLJs.

Thermodynamics and Microphysical Characteristics of an Extreme Rainfall Event Under the Influence of a Low-level Jet over the South China Coast

In this paper,the data of Automatic Weather Stations(AWSs),ERA5 reanalysis,sounding,wind profile radar,and dual-polarization radar are used to study an extreme rainfall event in the south China Coast on 11 to 12 May 2022 from the aspects of thermodynamics and microphysical characteristics under the influence of low-level jets(LLJs).Results show that:(1)The extreme rainfall event can be divided into two stages:the first stage(S1)from 0000 to 0600 LST on May 12 and the second stage(S2)from 0700 to 1700 LST on the same day.During S1,the rainfall is mainly caused by the upper-level shortwave trough and the boundary layer jet(BLJ),characterized by strong upward motion on the windward side of mountains.In S2,the combined influence of the BLJ and synoptic-system-related low-level jet(SLLJ)increases the vertical wind shear and vertical vorticity,strengthening the rainstorm.In combination with the effect of topography,a warm and humid southwest flow continuously transports water vapor to farther north,resulting in a significant increase in rainfall over the study area(on the terrain’s windward slope).From S1 to S2,the altitude of a divergence center in the upper air decreases obviously.(2)The rainfalls in the two stages are both associated with the mesoscale convergence line(MCL)on the surface,and the wind field from the mesoscale outflow boundary(MOB)in S1 is in the same direction as the environmental winds.Due to a small area of convergence that is left behind the MOB,convection moves eastward quickly and causes a short duration of heavy rainfall.In S2,the convergence along the MOB is enhanced,which strengthens the rainfall and leads to strong outflows,further enhancing the surface convergence near the MOB and forming a positive feedback mechanism.It results in a slow motion of convection and a long duration of heavy rainfall.(3)In terms of microphysics,the center of a strong echo in S1 is higher than in S2.The warm-rain process of the oceanic type characterizes both stages,but the convective intensity in S2 is significantly stronger than that in S1,featuring bigger drop sizes and lower concentrations.It is mainly due to the strengthening of LLJs,which makes small cloud droplets lift to melting levels,enhancing the ice phase process(riming process),producing large amounts of graupel particles and enhancing the melting and collision processes as they fall,resulting in the increase of liquid water content(LWC)and the formation of large raindrops near the surface.

Analysis of the Characteristics of the Low-level Jets in the Middle Reaches of the Yangtze River during the Mei-yu Season

Here,we analyze the characteristics and the formation mechanisms of low-level jets(LLJs)in the middle reaches of the Yangtze River during the 2010 mei-yu season using Wuhan station radiosonde data and the fifth generation of the European Centre for Medium-Range Weather Forecasts(ERA5)reanalysis dataset.Our results show that the vertical structure of LLJs is characterized by a predominance of boundary layer jets(BLJs)concentrated at heights of 900-1200 m.The BLJs occur most frequently at 2300 LST(LST=UTC+8 hours)but are strongest at 0200 LST,with composite wind velocities>14 m s^(-1).Synoptic-system-related LLJs(SLLJs)occur most frequently at 0800 LST but are strongest at 1100LST,with composite wind velocities>12 m s^(-1).Both BLJs and SLLJs are characterized by a southwesterly wind direction,although the wind direction of SLLJs is more westerly,and northeasterly SLLJs occur more frequently than northeasterly BLJs.When Wuhan is south of the mei-yu front,the westward extension of the northwest Pacific subtropical high intensifies,and the low-pressure system in the eastern Tibetan Plateau strengthens,favoring the formation of LLJs,which are closely related to precipitation.The wind speeds on rainstorm days are greater than those on LLJ days.Our analysis of four typical heavy precipitation events shows the presence of LLJs at the center of the precipitation and on its southern side before the onset of heavy precipitation.BLJs were shown to develop earlier than SLLJs.

Effects of Kangfuxin Solution (康复新液) Combined with Low-level Laser on Cytokines and Immune Function in Patients with Radiation-induced Oral Mucositis

Objective:To investigate the effect of Kangfuxin Solution(康复新液)combined with low-level laser therapy(LLLT)on cytokines and immune function in patients with radiation-induced oral mucositis.Methods:There were 84 nasopharyngeal carcinoma patients with oral mucositis after intensity-modulated radiation therapy(IMRT)were randomly divided into the control group(CG)and the observation group(OG),with 42 cases in each group.The CG was given LLLT,and the OG was treated with Kangfuxin Solution in addition to LLLT for 10 consecutive days.The healing time of oral mucosa,mucositis grading,oral pain scores,cytokines(interleukin-6,interleukin-1βand tumor necrosis factor-α)and T lymphocyte subsets were compared between the 2 groups before and after treatment.Results:The healing time of oral mucosa in the OG was(6.8±1.4)d,which was significantly shorter than(8.6±1.9)d in the CG(t=4.943,P<0.01).After treatment,the grading of oral mucositis in the OG was better than that in the CG,with a statistically significant difference(Z=2.942,P<0.05).The oral pain scores of the OG was lower than that in the CG at different time points after treatment,and the difference was statistically significant(t=8.207,11.017,P<0.01).After treatment,the levels of IL-6,IL-1βand TNF-αin peripheral blood of the OG were significantly lower than those in the CG(t=5.217,2.775,4.053,P<0.01).There were statistically significant differences in CD4+,CD8+and CD4+/CD8+between the OG and the CG after treatment(t=5.692,6.093,3.658,P<0.01).Conclusion:Kangfuxin Solution combined with LLLT can significantly shorten the healing time of oral mucosal,reduce the grading of oral mucositis,relieve oral pain,reduce inflammatory response and improve the immune function of patients.

免疫磁珠富集水中鲤春病毒血症病毒的初步研究

为建立一种富集水中鲤春病毒血症病毒(SVCV)的技术,本研究利用SVCV多克隆抗体制备免疫磁珠,通过对磁珠耦联抗体量的优化,确定该免疫磁珠有效富集SVCV的最低浓度,建立一种富集SVCV的免疫磁珠分离技术,并联合荧光定量RT-PCR(RT-qPCR)技术对水中SVCV进行检测。结果显示,1 mg磁珠与75μg SVCV多克隆抗体耦联时,耦联的抗体量最大,耦联率为98.48%;耦联后的免疫磁珠对SVCV(200μL,浓度为1.54×10^(6)拷贝/μL)的富集效率最高为91.56%。以该多克隆抗体量制备的免疫磁珠富集10倍倍比稀释的SVCV(3.54×10^(6)拷贝/μL~3.54×10^(3)拷贝/μL),以确定其有效富集SVCV的最低浓度。结果显示,1 mg免疫磁珠能够使200μL病毒液(3.54×10^(3)拷贝/μL)富集率达到61.58%。表明该免疫磁珠能够有效富集SVCV。在免疫磁珠分离技术联合RT-qPCR技术检测水样品中SVCV(浓度约为1.16×10^(4)拷贝/μL)的结果显示,免疫磁珠组富集SVCV核酸量是裸磁珠组富集SVCV核酸量的1.77×10^(3)倍,是未处理组富集SVCV核酸量的1.68×10^(3)倍,免疫磁珠组富集SVCV均极显著高于裸磁珠组和未处理组(P<0.01),裸磁珠组富集的SVCV与未处理组则无显著差异(P>0.05)。本研究首次建立了一种能够有效富集水中SVCV的方法,为SVCV的监测提供了技术手段。

一线核苷(酸)类似物经治的慢性乙型肝炎患者低病毒血症的发生及治疗策略

强效低耐药口服抗病毒治疗可使HBV复制受到强力抑制,但部分患者接受恩替卡韦、替诺福韦酯、丙酚替诺福韦、艾米替诺福韦治疗48周及以上仍存在低病毒血症(LLV)。国内外多项研究结果提示,抗病毒治疗后LLV与慢性乙型肝炎肝纤维化进展、失代偿期肝硬化和肝细胞癌发生风险以及长期生存率降低密切相关。因此,本文聚焦有关一线核苷(酸)类似物治疗后LLV的发生及其危险因素和临床危害以及不同的治疗方案,以期为今后慢性乙型肝炎患者LLV的治疗提供参考。

慢乙肝低病毒血症患者继续核苷(酸)类似物治疗的远期临床结局:一项系统评价和Meta分析

背景一线核苷(酸)类似物(nucleos(t)ide analogues,NAs)经治后发生低病毒血症(low-level viremia,LLV)的慢乙肝患者,继续使用NAs治疗的远期临床结局的研究尚缺乏.目的采用系统评价和Meta分析对慢乙肝经一线NAs治疗的LLV患者继续原NAs治疗和更换不同NAs治疗方案远期临床结局情况进行评价.方法经计算机检索PubMed、Embase、Web of Science、Cochrane Library数据库和中国知网(CNKI)、万方数据库,选取符合纳入标准的研究,使用R 4.3.1软件对纳入研究数据进行Meta分析.结果最终纳入11篇文献,涉及3153例慢乙肝LLV患者,其中7篇文献进行HBV DNA阴转率定量Meta分析,结果提示更换NAs方案组继续治疗24 wk[RR=4.23,95%CI(2.47,7.24),P<0.01]和48 wk[RR=2.90,95%CI(1.75,4.81),P<0.01]后HBV DNA阴转率明显高于继续原NAs方案组;纳入6篇文献进行HBeAg阴转率的定量Meta分析,更换NAs治疗方案组24 wk HBeAg阴转率高于继续原方案组[RR=2.31,95%CI(1.28,4.19),P<0.01],但48 wk两组HBeAg阴转率差异无统计学意义[RR=1.50,95%CI(0.88,2.54),P=0.13];纳入3篇文献进行终末期肝病发生率的定性系统评价,结果显示继续NAs治疗的LLV组患者远期终末期肝病发生率均高于维持病毒学应答(maintain virological response,MVR)组,差异均具有统计学意义(P<0.05).结论更换NAs治疗方案可提高慢乙肝LLV患者HBV DNA阴转率和HBeAg阴转率,但继续NAs方案治疗的慢乙肝LLV患者远期终末期肝病发生率较MVR患者高.

中国肾移植受者巨细胞病毒感染临床诊疗指南(2023版)

近几年在实体器官移植(SOT)受者巨细胞病毒(CMV)感染诊疗领域,无论是诊断方法还是新型抗CMV药物都有了一些新的进展,对CMV感染的诊治产生了积极的影响。为了进一步规范中国肾移植术后CMV感染的管理,中华医学会器官移植学分会组织了国内多个学科相关领域专家,参考《中国实体器官移植受者巨细胞病毒感染诊疗指南(2016版)》和国内外已发表的最新文献和指南,制定了《中国肾移植受者巨细胞病毒感染诊疗指南(2023版)》,新版指南更新了CMV流行病学,CMV感染的危险因素和普遍性预防的研究进展,新增CMV感染定义,细化CMV血症和CMV病的诊断标准,并对新型抗CMV药物进行了介绍。

恩替卡韦治疗后慢性乙型肝炎低病毒血症患者序贯联合艾米替诺福韦治疗的效果研究

目的 探讨在恩替卡韦(ETV)治疗后出现低病毒血症(LLV)的慢性乙型肝炎(CHB)患者,采取序贯联合艾米替诺福韦(TMF)治疗的临床效果。方法 选取2021年7月—2023年1月在贵港市人民医院感染科经ETV抗病毒治疗的CHB患者200例。根据治疗期间HBV DNA水平,将患者分为完全病毒学应答组(64例)和LLV组(136例),分析两组临床资料。根据LLV组抗病毒治疗方案,分为3组:续用ETV为对照组(40例)、换用TMF为序贯组(45例)、ETV联合TMF为联合组(51例),持续治疗48周。比较3组治疗48周时HBV DNA转阴率、乙肝表面抗原(HBsAg)、E抗原(HBeAg)、丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、肌酐(Cr)和肝硬度测定值(LSM)及不良反应发生率。结果 完全病毒学应答组HBeAg阳性率、HBV DNA、PLT、LSM、ALT、AST均低于LLV组(P <0.05)。治疗24周后,完全病毒学应答组Cr、AST、HBeAg阳性率、HBV DNA、PLT均低于LLV组(P <0.05)。治疗48周后,联合组Cr低于对照组和序贯组(P <0.05),HBsAg高于对照组和序贯组(P <0.05);序贯组ALT、AST均低于对照组(P <0.05);序贯组和联合组HBeAg转阴率、HBV DNA转阴率、PLT均高于对照组(P <0.05),LSM低于对照组(P <0.05)。对照组、序贯组、联合组不良反应总发生率比较,差异无统计学意义(P>0.05)。结论 序贯或联合TMF治疗能更有效地提高ETV治疗后LLV患者完全病毒学应答率,并改善患者肝肾功能,减轻肝纤维化程度。

经治慢性乙型肝炎患者低病毒血症发生率和影响因素的Meta分析

目的系统评价慢性乙型肝炎(CHB)患者低病毒血症(LLV)的发生率及其影响因素,为临床有效干预和预防LLV的发生提供循证医学证据。方法本研究根据PRISMA指南完成,PROSPERO注册号:CRD42023455304。计算机检索中国知网、万方数据库、维普、中国生物医学文献服务系统、PubMed、Embase、Web of Science、Cochrane Library中有关CHB患者LLV发生及影响因素的观察性研究,检索时间为建库至2023年7月21日。应用Stata 16.0软件进行Meta分析。结果共纳入文献12篇,总样本量3408例,包括LLV患者1181例。Meta分析结果显示,经治CHB患者LLV发生率为32.8%(95%CI:27.6%~38.3%);HBsAg定量高(OR=2.107,95%CI:1.782~2.491,P<0.001)、HBeAg阳性(OR=3.258,95%CI:2.629~4.038,P<0.001)、高基线HBV DNA水平(OR=1.286,95%CI:1.157~1.430,P<0.001)及有恩替卡韦治疗史(OR=3.089,95%CI:1.880~5.074,P<0.001)是LLV发生的危险因素;抗病毒时间≥3年(OR=0.175,95%CI:0.093~0.331,P<0.001)和高基线ALT水平(OR=0.985,95%CI:0.978~0.992,P<0.001)是LLV的保护因素。敏感性分析显示效应值未发生明显变化,提示Meta分析结果相对稳定。纳入研究漏斗图基本对称,Egger’s检验和Begg’s检验结果提示纳入文献不存在明显发表偏倚。结论临床医生应根据LLV的影响因素,综合临床证据有效指导决策,降低远期临床风险,避免不良结局。

中华鲟IFNe2的抗病毒天然免疫作用

为探究中华鲟干扰素e2(AsIFNe2)的免疫调控作用,本实验通过原核表达获得了重组中华鲟干扰素e2蛋白(rAsIFNe2),并分析其对抗病毒相关基因的影响及其抗病毒活性。实时荧光定量PCR(RT-qPCR)结果显示,rAsIFNe2能显著激活中华鲟鳍细胞中干扰素刺激基因(IFN-stimulated genes,ISGs)的表达,如Mx、PKR、Viperin和ADAR4。此外,rAsIFNe2还能通过激活IRFs和IFNes基因的表达,从而帮助宿主细胞迅速建立抗病毒状态。在鲤春病毒血症病毒(SVCV)感染鲤上皮细胞(EPC)模型中,rAsIFNe2能够诱导EPC细胞中Mx、PKR和Viperin的表达,并降低EPC细胞中SVCV病毒G、N和P基因的表达,减少病变效应的产生。研究表明,AsIFNe2在宿主抗病毒天然免疫反应中发挥作用。本研究为深入了解中华鲟的干扰素免疫系统以及治疗病毒性疾病提供理论依据。

Assessment of Wet Season Precipitation in the Central United States by the Regional Climate Simulation of the WRFG Member in NARCCAP and Its Relationship with Large-Scale Circulation Biases

Assessment of past-climate simulations of regional climate models(RCMs)is important for understanding the reliability of RCMs when used to project future regional climate.Here,we assess the performance and discuss possible causes of biases in a WRF-based RCM with a grid spacing of 50 km,named WRFG,from the North American Regional Climate Change Assessment Program(NARCCAP)in simulating wet season precipitation over the Central United States for a period when observational data are available.The RCM reproduces key features of the precipitation distribution characteristics during late spring to early summer,although it tends to underestimate the magnitude of precipitation.This dry bias is partially due to the model’s lack of skill in simulating nocturnal precipitation related to the lack of eastward propagating convective systems in the simulation.Inaccuracy in reproducing large-scale circulation and environmental conditions is another contributing factor.The too weak simulated pressure gradient between the Rocky Mountains and the Gulf of Mexico results in weaker southerly winds in between,leading to a reduction of warm moist air transport from the Gulf to the Central Great Plains.The simulated low-level horizontal convergence fields are less favorable for upward motion than in the NARR and hence,for the development of moist convection as well.Therefore,a careful examination of an RCM’s deficiencies and the identification of the source of errors are important when using the RCM to project precipitation changes in future climate scenarios.