气候变化和经济发展对肾综合征出血热发生的影响

肾综合征出血热(hemorrhagic fever with renal syndrome,HFRS)是一种啮齿动物传播的自然疫源性疾病,危害严重,已成为全球重要的公共卫生问题。本研究采用数理统计模型及小波分析方法,对陕西省西安市鄠邑区1984–2016年HFRS的发生与鼠类、气候和经济因素的关系进行分析,探讨气候和经济因素对HFRS发生的影响。小波分析结果表明,该地区的HFRS暴发史可能分为两个时期,推测每个时期具有不同的主要宿主,在2002年褐家鼠(Rattus norvegicus)可能取代黑线姬鼠(Apodemus agrarius)成为HFRS疫源地的主要宿主。广义可加模型模拟结果表明,HFRS的发生与1984–2001年黑线姬鼠密度间存在极显著非线性效应(F_(2.06,9.02)=102.415,P<0.01),两者间显现为正相关;与2002–2016年的褐家鼠密度间呈正相关(F_(1.67,9.02)=73.929,P<0.01);HFRS主要宿主的这种变化可能与当地气候变化和经济发展有关:HFRS的发生与年平均温度存在极显著的非线性效应(F_(2.93,9.02)=12.164,P<0.01),两者间呈负相关;同样,HFRS的发生与上一年的国内生产总值(GDP)也存在显著非线性效应(F_(1.70,9.02)=2.917,P<0.05),两者间也呈负相关。结构方程模型通过直接和间接的影响途径证明了这种转移机制,发现温度对HFRS发生有显著的直接负向影响以及通过褐家鼠的间接正向影响;GDP对HFRS发生有直接的负向影响。本研究表明HFRS的发生与气候变化和经济发展相关,两者均能影响HFRS的暴发,该结论有助于今后更好地对HFRS疾病进行预防和控制。

Effects of proton pump inhibitor on gastroesophageal varices in patients with cirrhosis:A randomized controlled trial from China

Aims:Proton pump inhibitors(PPI)are widely used for gastroesophageal varices in patients with cirrhosis after endoscopic therapy,although the effect of PPI on these patients remains controversial.This study aimed to evaluate the effect of PPI on gastroesophageal varices in patients with cirrhosis after endoscopic therapy,including variceal bleeding and adverse events.Methods:Cirrhotic patients with endoscopically confirmed gastroesophageal varices were enrolled in this study between May 2017 and June 2019.Eligible patients were randomized into two groups:one group received PPI for 14 days and the other group did not receive PPI treatment(n=53 in each group).All patients were followed for 8 weeks.Results:During the follow‐up period,three patients(5.66%)in the PPI group experienced variceal bleeding on days 9,16,and 25 after endoscopic therapy,including two patients with acute bleeding and one with primary prophylaxis.In the non‐PPI group,three patients(5.66%)experienced variceal bleeding on days 7,42,and 56 after endoscopic therapy,including one patient with acute bleeding and two with secondary prophylaxis(p=0.990).The incidence of adverse events was similar between the two groups(37.74%vs.28.30%,p=0.30).Conclusions:PPI did not appear to reduce variceal bleeding and adverse events in patients with cirrhosis after endoscopic therapy.

An overview of reclaimed water reuse in China

China is facing severe water problems including scarcity and pollution which are now becoming key factors restricting developments. Creating an alternative water resource and reducing effluent discharges, water reuse has been recognized as an integral part of water and wastewater management scheme in China. The government has launched nationwide efforts to optimize the benefits of utilizing reclaimed water. This article reviewed the water reuse activities in China, including： （1） application history and current status; （2） potentials of reclaimed water reuse; （3） laws, policies and regulations governing reclaimed water reuse; （4） risks associated with reclaimed water reuse; （5） issues in reclaimed water reuse. Reclaimed water in Beijing and Tianjin were given as examples. Suggestions for improving the efficiencies of reusing urban wastewater were advanced. Being the largest user of reclaimed wastewater in the world, China＇s experience can benefit the development of water reuse in other regions.

Validation of Non-invasive Fibrosis Scores for Predicting Advanced Fibrosis in Metabolic-associated Fatty Liver Disease

Background and Aims:Metabolic-associated fatty liver disease(MAFLD)is a newly proposed terminology from 2020;yet,the applicability of conventional noninvasive fi-brosis models is still unknown for it.We aimed to evaluate the performance of conventional noninvasive fibrosis scores in MAFLD.Methods:The NHANES 2017-2018 datasets were used to compare the performances of different non-invasive fibrosis scores in MAFLD,including the aspartate aminotransferase(AST)to platelet ratio index(APRI),body mass index(BMI)-AST/alanine aminotransferase(ALT)ratio and diabetes score(BARD),fibrosis-4 index(FIB-4),and NAFLD fibrosis score(NFS).Moreover,Asian patients with biopsy-proven MAFLD were enrolled to further validate the findings.Results:A total of 2,622 participants in the Na-tional Health and Nutrition Examination Survey(NHANES)cohort and 293 patients with MAFLD in the Asian cohort were included.Patients in the Asian cohort had a lower BMI and higher liver enzymes(p<0.001).The area under the receiver operating characteristic curve(AUROC)of NFS was the largest in the NHANES cohort and Asian cohorts(0.679 and 0.699,respectively).The AUROC of NFS was followed by APRI,FIB-4,and BARD in the NHANES cohort(0.616,0.601,and 0.589,respectively).In the Asian cohort,the AUROC of APRI,FIB-4,and BARD for predicting advanced fibrosis were 0.625,0.683,and 0.615,respectively.The performance of FIB-4 was better in the Asian cohort than that in the NHANES cohort.Conclusions:NFS is better for predicting advanced fibrosis in MAFLD.FIB-4 can be an al-ternative choice for MAFLD with high liver enzymes when NFS is unavailable.Novel efficient noninvasive fibrosis scor-ing systems are highly required for patients with MAFLD.

Seed traits and rodent community interact to determine seed fate:evidence from both enclosure and field experiments

Animal-mediated seed dispersal is an important ecological process in which a strong mutualism between animals and plants can arise.However,few studies have examined how a community of potential seed dispersers interacts with sympatric seed trees.We employed a series of experiments in the Qinling Mountains in both semi-natural enclosure and the field to assess the interactions among 3 sympatric rodent species and 3 Fagaceae tree seeds.Seed traits all showed similar tannin levels but markedly different physical traits and nutritional contents.We found that seeds with heavy weight,thick coat,and high nutritional contents were less likely to be eaten in situ but more often to be eaten after dispersal or hoarded by rodents.These results support both the handling time hypothesis and the high nutrition hypothesis.Surprisingly,we also found that rodents,maybe,preferred to consume seeds with low levels of crude fiber in situ,and to harvest and hoard those with high levels of crude fiber for later consumption.The sympatric rodent species,Cansumys canus,the largest rodent in our study,harvested and hoarded more Quercus variabilis seeds with high physical and nutritional traits,while Apodemus draco,the smallest rodent,harvested more Q.serrata seeds with low physical and nutritional traits,and Niviventer confucianus harvested and hoarded more Q.aliena seeds with medium physical and nutritional traits.Our study demonstrates that different seed traits play different roles in influencing the seed fate and the shaping of mutualism and predation interactions within a community of rodent species.

Effects of insect infestation on rodent-mediated dispersal of Quercus aliena:results from field and enclosure experiments

Rodents influence plant establishment and regeneration by functioning as both seed predators and dispersers.However,these rodent-plant interactions can vary significantly due to various environmental conditions and the activity of other insect seed predators.Here,we use a combination of both field and enclosure(i.e.individual cage and semi-natural enclosure)experiments,to determine whether rodents can distinguish sound seeds from those infested with insects.We also demonstrate how such responses to insects are influenced by food abun-dance and other environmental factors.We presented rodents with 2 kinds of Quercus aliena seeds(sound and insect-infested seeds)in a subtropical forest in the Qinling Mountains,central China,from September to No-vember of 2011 to 2013.The results showed that rodents preferred to hoard and eat sound seeds than infested seeds in the field and semi-natural enclosure,while they preferred to eat infested seeds over sound seeds in the individual cages.In addition,both hoarding and eating decisions were influenced by food abundance.Rodents hoarded more sound seeds in years of high food abundance while they consumed more acorns in years of food shortage.Compared with field results,rodents reduced scatter-hoarding behavior in semi-natural enclosures and ate more insect-infested seeds in smaller individual cages.These results further confirm that rodents distinguish infested seeds from non-infested seeds but demonstrate that this behavior varies with conditions(i.e.environ-ment and food abundance).We suggest that such interactions will influence the dispersal and natural regenera-tion of seeds as well as predation rates on insect larvae.

Anti-fertility effect of levonorgestrel and/or quinestrol on striped field mouse(Apodemus agrarius):evidence from both laboratory and field experiments

The effect of combined levonorgestrel(P)and quinestrol(E)on the fertility of stripedfield mouse(Apodemus agrarius)has not been evaluated.We performed a series of experiments in both the laboratory andfield to assess the effect of P and/or E on the fertility of A.agrarius.In the laboratory,to test the time-dependent anti-fertility ef-fects of P and E,as well as their mixtures,90 male stripedfield mice were randomly assigned to 6 treatment groups(n=60),and a control group(n=30).Mice in 3 treatment groups were administered 1 of the 3 compounds(1 mg�kg–1[body weight]EP-1,0.34 mg�kg–1 E,0.66 mg�kg–1 P)for 3 successive days(another half for 7 suc-cessive days)via oral gavage;mice were then sacrificed 15 and 45 days after initiating the gavage treatment.Ourfindings indicated that E and EP-1 treatment,but not P or control treatment,significantly decreased the sperm count in the caudal epididymis,as well as the weight of the testes,epididymides,and seminal vesicles.Additionally,fer-tile female mice mated with E-and EP-1-treated males produced smaller pups.These data indicate that E and EP-1 can induce infertility in male A.agrarius.In thefield,the population density of A.agrarius was significantly influ-enced by EP-1,and the rodent density in the treatment group was lower than that in the control group.Overall,our results indicate that EP-1 is an effective contraceptive in A.agrarius,a dominant rodent species in the farmland.

Phylogeography of Gyrodactylus konovalovi(Monogenoidea:Gyrodactylidae) in the Qinling Mountains in Central China

Gyrodactylus konovalovi is an ectoparasite on the Amur minnow(Rhynchocypris lagowskii)that is widely distributed in the cold fresh waters of East Asia.In the present study,the phylogeography of G.konovalovi and the distribution of its host in the Qinling Mountains are examined.A total of 102 parasite specimens was sequenced for the mitochondrial cytochrome oxidase subunit 1(cox1)gene,and 43 haplotypes were obtained.The ratio of substitution sites(dN/dS)was 0.016 and indicated strongly purifying selection.Haplotype diversity(h)and nucleotide diversity(π)of suprapopulations of G.konovalovi varied widely between distinct localities from the Qinling Mountains.Phylogenetic trees based on Bayesian inference(BI),maximum likelihood(ML)and maximum parsimony(MP)methods and network analysis revealed that all haplotypes were consistently well-supported in three different lineages A,B,and C,indicating a significant geographic distribution pattern.There was a significant positive correlation between genetic differentiation(Fst)and geographic distance(P<0.001).The results of mismatch distribution,neutrality test and Bayesian skyline plot analyses showed that lineages A and B underwent population expansion after the Last Glacier Maximum(LGM)during the Late Pleistocene,while the lineage C underwent population contraction during the Middle to Late Pleistocene.Based on the molecular clock calibration,the most common ancestor was estimated to have emerged in the Middle to Late Pleistocene.Our study suggests that a clearly phylogeography of G.konovalovi was shaped by climatic oscillation and geological events,such as orogenesis,drainage capture changes and vicariance,during the Pleistocene in the Qinling Mountains in central China.