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Viral hepatitis:Past,present,and future

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World Journal of gastroenterology 2022年第14期28卷 1405-1429页

作者： Matthew august Odenwald Sonali Paul Department of Medicine Section of GastroenterologyHepatologyand NutritionCenter for Liver DiseasesUniversity of ChicagoChicagoIL 60637United States

each hepatitis virus—Hepatitis A,B,C,D,e,and g—poses a distinct scenario to the patient and clinician *** the discovery of each virus,extensive knowledge regarding epidemiology,virologic properties,and the natural clinical and immunologic history of acute and chronic infections has been *** discoveries about host immunologic responses to acute and chronic viral infections,combined with virologic data,has led to vaccines to prevent Hepatitis A,B,and e and highly efficacious antivirals for Hepatitis B and *** therapeutic breakthroughs are transforming the fields of hepatology,transplant medicine in general,and public and global *** notably,there is even an ambitious global effort to eliminate chronic viral hepatitis within the next *** attainable,there are many barriers to this goal that are being actively investigated in basic and clinical labs on the local,national,and international ***,we discuss pertinent clinical information and recent organizational guidelines for each of the individual hepatitis viruses while also synthesizing this information with the latest research to focus on exciting future directions for each virus.

关键词： Viral Hepatitis Hepatitis A Hepatitis B Hepatitis C Hepatitis D Hepatitis e Hepatitis g

Stem cell autotomy and niche interaction in different systems

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World Journal of Stem Cells 2015年第6期7卷 922-944页

作者： David C Dorn august Dorn Department of Hematology HemostasisOncologyand Stem Cell TransplantationHannover Medical School Institute of Zoology Johannes Gutenberg University

The best known cases of cell autotomy are the formation of erythrocytes and thrombocytes(platelets) from progenitor cells that reside in special niches. Recently, autotomy of stem cells and its enigmatic interaction with the niche has been reported from male germline stem cells(gSCs) in several insect species. First described in lepidopterans, the silkmoth, followed by the gipsy moth and consecutively in hemipterans, foremost the milkweed bug. In both, moths and the milkweed bug, gSCs form finger-like projections toward the niche, the apical cells(homologs of the hub cells in Drosophila). Whereas in the milkweed bug the projection terminals remain at the surface of the niche cells, in the gipsy moth they protrude deeply into the singular niche cell. In both cases, the projections undergo serial retrograde fragmentation with progressing signs of autophagy. In the gipsy moth, the autotomized vesicles are phagocytized and digested by the niche cell. In the milkweed bug the autotomized vesicles accumulate at the niche surface and disintegrate. Autotomy and sprouting of new projections appears to occur continuously. The significance of the gSC-niche interactions, however, remains enigmatic. Our concept on the signaling relationship between stem cell-niche in general and gSC and niche(hub cells and cyst stem cells) in particular has been greatly shaped by Drosophila melanogaster. In comparing the interactions of gSCs with their niche in Drosophila with those in species exhibiting gSC autotomy it is obvious that additional or alternative modes of stem cell-niche communication exist. Thus, essential signaling pathways, including niche-stem cell adhesion(e-cadherin) and the direction of asymmetrical gSC division- as they were found in Drosophila- can hardly be translated into the systems where gSC autotomywas reported. It is shown here that the serial autotomy of gSC projections shows remarkable similarities with Wallerian axonal destruction, developmental axon pruning and d

关键词： Stem cell-niche interaction Male germlinestem cells Spermatogenesis erythropoiesis Stem cellautotomy Thrombopoiesis

evaluation of habitat requirements of small rodents and effectiveness of an ecologically-based management in a hantavirus-endemic natural protected area in Argentina

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Integrative Zoology 2017年第1期12卷 77-94页

作者： María Victoria VADeLL Francisco gARCÍA eRIZe Isabel elisa gÓMeZ VILLAFAÑe Department of ecology Genetics and Evolution.Institute of EcologyGenetics and Evolution(IEGEBA-CONICET).University of Buenos AiresBuenos AiresArgentina Institute of Research and environmental engineering(3iA).University of San Martín San MartínBuenos AiresArgentina

Hantavirus pulmonary syndrome is a severe cardio pulmonary disease transmitted to humans by sylvan rodents found in natural and rural *** transmission is closely linked to the ecology of animal reservoirs and abiotic factors such as habitat characteristics,season or climatic *** main goals of this research were:to determine the biotic and abiotic factors affecting richness and abundance of rodent species at different spatial scales,to evaluate different methodologies for studying population of small rodents,and to describe and analyze an ecologically-based rodent management experience in a highly touristic area.A 4-year study of small rodent ecology was conducted between April 2007 and august 2011 in the most relevant habitats of el Palmar National Park,*** involved a wide range of control and prevention measures,including poisoning,culling and habitat modification.A total of 172 individuals of 5 species were captured with a trapping effort of 13860 traps-nights(1.24 individuals/100 traps-nights).Five rodent species were captured,including 2 hantavirus-host species,Oligoryzomys nigripes and Akodon *** nigripes,host of a hantavirus that is pathogenic in humans,was the most abundant species and the only one found in all the studied *** results are inconsistent with the dilution effect *** present study demonstrates that sylvan rodent species,including the hantavirus-host species,have distinct local habitat selection and temporal variation patterns in abundance,which may influence the risk of human exposure to hantavirus and may have practical implications for disease transmission as well as for reservoir management.

关键词： abundance disease prevention habitat use population dynamics zoonosis

Response of the Ionospheric F_2-region Over Irkutsk and Hainan to Strong geomagnetic Storms

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空间科学学报 2013年第5期33卷 494-500页

作者： e B Romanova g A Zherebtsov K g Ratovsky N M Polekh J K Shi X Wang g J Wang Institute of Solar-Terrestrial Physics Siberian BranchRussian Academy of Sciences State Key Laboratory of Space Weather Center for Space Science and Applied ResearchChinese Academy of Sciences

The ionospheric responses to two strong storms on 17-19 august 2003 and 22-23 January 2004 are studied,using the data from Irkutsk(52.5°N,104°e) and Hainan(19.5°N,109°e) ionospheric *** analysis of variations in relative deviations of the critical frequency △f_0F_2 revealed that at middle latitudes(Irkutsk) negative disturbances were observed in the summer ionosphere; positive and negative ones,in the winter ionosphere during the main and recovery phases *** low latitudes(Hainan),the disturbances were positive in all the cases considered. Mechanisms of the disturbances were analyzed with the aid of empirical models of the neutral atmosphere NRLMSISe-00 and thermospheric wind *** main factors determining △f_0F_2 variations at middle latitudes during the storms were demonstrated to be the disturbed equatorward thermospheric wind transporting the disturbed atmospheric composition,the increase in the atomic oxygen concentration,and the passage of internal gravity *** low latitudes,the effects associated with neutral composition variations are less significant than those of the thermospheric wind and electric fields.

关键词： Ionosphere geomagnetic storm Thermospheric wind Drift

区域旅游流空间结构的高铁效应及机理--以中国京沪高铁为例

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地理学报 2015年第2期70卷 214-233页

作者：汪德根陈田陆林王莉 ALAN august Lew 苏州大学旅游系苏州215123 北亚利桑那大学地理、规划与休闲系美国亚利桑那弗拉格斯塔夫86001 中国科学院地理科学与资源研究所北京100101 安徽师范大学国土资源与旅游学院芜湖241002

交通是影响旅游流空间结构最主要因素之一。以京沪高铁线为例,探讨了区域旅游流空间结构的高铁效应及特征,在此基础上,分析区域交通可达性变化,并结合区域旅游资源禀赋、区域旅游接待设施、区域旅游交通网络密度以及区位等影响因素分析... 详细信息

交通是影响旅游流空间结构最主要因素之一。以京沪高铁线为例,探讨了区域旅游流空间结构的高铁效应及特征,在此基础上,分析区域交通可达性变化,并结合区域旅游资源禀赋、区域旅游接待设施、区域旅游交通网络密度以及区位等影响因素分析区域旅游流空间结构的高铁效应的机理。研究表明:1区域旅游流空间结构的高铁效应表现为马太效应、过滤效应、扩散效应和叠加效应等特征。2区位条件、旅游资源禀赋、旅游接待能力、交通网络密度以及时空压缩程度等影响因素共同作用均非常明显态势下,产生高铁马太效应;旅游资源禀赋、旅游接待能力、交通网络密度均不强,时空压缩程度不显著等旅游节点产生高铁过滤效应;区位条件、旅游资源禀赋、旅游接待能力和交通网络密度均具有很强优势,且时空压缩程度明显等旅游节点可成为扩散源,高铁强化了扩散源旅游流集聚作用,然后向边缘旅游地扩散,呈现为"集聚—扩散"模式;高铁使大尺度空间的不同客源地居民出游空间范围出现叠加现象,但只有区位条件、旅游资源禀赋、旅游接待能力、交通网络密度优势较强且时空压缩程度明显旅游节点产生叠加效应。

关键词：旅游流空间结构高铁效应机理京沪高铁中国

Monitoring of brown stink bug (Hemiptera: Pentatomidae) population dynamics in corn to predict its abundanee using weather data

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Insect Science 2019年第3期26卷 536-544页

作者： Xinzhi Ni Ted e. Cottrell g. David Buntin Xianchun Li Wei Wang Hong Zhuang USDA-ARS Crop Genetics and Breeding Research Unit Tifton Georgia USA USDA-ARS Southeastern Fruit and Tree Nut Research Laboratory Byron Georgia USA Department of entomology University of Georgia Griffin Georgia USA Department of entomology University of Arizona Tucson Arizona USA College of engineering China Agricultural University Beijing China USDA-ARS Quality and Safety Assessment Research Unit Athens Georgia USA

The brown stink bug (BSB), euschistus servus (Say)(Hemiptera: Pentatomidae), is a serious economic pest of corn production in the southeastern United States. The BSB population dynamics was mon itored for 17 weeks from tasseling to preharvest of corn plants (i.e., late May to mid-September) using pheromone traps in three corn fields from 2005 to 2009. The trap data showed two peaks in early June and mid-august, respectively. The relationship between trap catch and pregrowing season weather data was examined using correlation and stepwise multiple factor regression analyses. Weather indices used for the analyses were accumulated growing degree day (AgDD), number of days with minimum temperature below 0℃(Subz), accumulated daily maximum (AMaxT) and minimum temperatures (AMinT) and rainfall (ARain). The weather indices were calculated with lower (10℃) and upper (35℃) as biological thresholds. The parameters used in regression analysis were seasonal abundance (or overall mean of BSB adult catch)(BSBm), number of BSB adults caught at a peak (PeakBSB), and peak week (Peakwk). The BSBm was negatively related to high temperature (AmaxT or AgDD) consistently, whereas IstPeakBSB was positively correlated to both ARain and Subz, irrespective of weather data durations (the first 4, 4.5, and 5 months). In contrast, the 7-month weather data (AgDD7) were negatively correlated to the BSBm only, but not correlated to the second PeakBSB. The 5-year monitoring study demonstrated that weather data can be used to predict the BSB abundance at its first peak in tasseling corn fields in the southeastern U.S. states.

关键词： euschistus servus first trap catch peak pheromone trap catch population dynamics stepwise regression modeling weekly mean

Differences in physiological and biochemical responses to summer drought of Pinus nigra *** and Pinus brutia in a natural mixed stand

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Journal of Forestry Research 2020年第5期31卷 1479-1487页

作者： Ayse Deligoz Fatma gokce Cankara Faculty of Forestry Isparta University of Applied Sciences32260 IspartaTurkey

Understanding how tree species respond to drought in their natural environment is needed to predict forest adaptation and management practices under global environmental *** study was carried out to determine and compare physiological and biochemical responses to variations in environmental conditions during summer drought of mixed natural stands of Pinus nigra ***(Lamb.)Holmboe and Pinus brutia *** xylem water potential(ψmd),water relations,photosynthetic pigments,total soluble sugar and proline contents were investigated during the growing season.ψmd followed a similar seasonal trend in both species but *** *** had higher ψmd than *** ψmd gradually decreased from June,reached its lowest value in august,and then increased *** decreases in the osmotic potential at turgor loss point(ψnTLP)were observed during the ***,ψnTLP was lower in *** soluble sugars decreased from April to June for ***,then increased and stayed relatively constant august to *** changes were found at lower values in *** *** accumulation and photosynthetic pigments were higher in *** results indicate that physiological and biochemical responses of both species against changing environmental conditions were in different degrees but followed similar *** *** is more sensitive to summer drought than *** in their natural environment.

关键词： Pinus nigra subsp.pallasiana Pinus brutia Osmotic potential Photosynthetic pigments Soluble sugars Proline Summer drought

Compound screening platform using human induced pluripotent stem cells to identify small molecules that promote chondrogenesis

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Protein & Cell 2012年第12期3卷 934-942页

作者： Sheng-Lian Yang erica Harnish Thomas Leeuw Uwe Dietz erika Batchelder Paul SWright Jane Peppard Paul august Cecile Volle-Challier Francoise Bono Jean-Marc Herbert Juan Carlos Izpisua Belmonte gene expression Laboratories The Salk Institute for Biological Studies10010 N.Torrey Pines Rd.La JollaCA 92037USA Sanofi US R&DEarly to Candidate UnitTucson Research Center2090 E.Innovation Park DriveTucsonAZ 85755USA Sanofi Deutschland gmbH R&DTSU Aging Quality of LifeIndustriepark HoechstFrankfurt am Main 65926Germany Sanofi R&D Early to Candidate Unit195Route d'Espagne-BP 13669ToulouseFrance Center of Regeneration Medicine Dr.Aiguader 88Barcelona 08003Spain

Articular cartilage,which is mainly composed of collagen Ⅱ,enables smooth skeletal *** of collagen Ⅱ can be caused by various events,such as injury,but degeneration especially increases over the course of normal ***,the body does not fully repair itself from this type of degeneration,resulting in impaired ***,an articular cartilage repair surgical technique,has been commonly used in the clinic to induce the repair of tissue at damage *** stem cells(MSC)have also been used as cell therapy to repair degenerated ***,the therapeutic outcomes of all these techniques vary in different patients depending on their age,health,lesion size and the extent of damage to the *** repairing tissues either form fibrocartilage or go into a hypertrophic stage,both of which do not reproduce the equivalent functionality of endogenous hyaline *** of the reasons for this is inefficient chondrogenesis by endogenous and exogenous *** that promote chondrogenesis could be used to induce self-repair of damaged cartilage as a non-invasive approach alone,or combined with other techniques to greatly assist the therapeutic *** recent development of human induced pluripotent stem cell(iPSCs),which are able to self-renew and differentiate into multiple cell types,provides a potentially valuable cell resource for drug screening in a“more relevant”cell *** we report a screening platform using human iPSCs in a multi-well plate format to identify compounds that could promote chondrogenesis.

关键词： heSC hiPSC chondrogenesis compound screening platform

effect of estradiol-17β on pituitary-thyroidal axis of Japanese eel (Anguilla japonica)

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Acta Oceanologica Sinica 2001年第4期20卷 585-596页

作者：曲宪成 Fisheries College Shanghai Fisheries University Shanghai 200090 334 Jungong Road China Department of environmental Biology Faculty of Environmental Studies Nagasaki University Nagasaki 852-8521 Japan Department of Biology Faculty of Fisheries Hokkaido University Hakodate 041-0821 3-1-1 Minato-cho Japan

The effect of estradiol-17β (e2)treatment on the pituitary-thyroidal axis has been investi- gated in female Japanese eels in seawater. The eels were injected with 1 mg/kg body weight (BW) weekly for two to eight weeks; another group was treated with 5 mg/kg BW weekly for eight weeks and sacrificed three days after the last injection. In the pituitary, using RT-PCR systern, the thyroid stim- ulating hormone 3 subunit mRNA (TSHβ MRNA) level is slowly increased in the low-dose e2 treatment group. A significant increase in values occurred after eight weeks e2 injections. The histological structure of the thyroid follicles suggests a hypo-activity as shown by a reduced epithelial cell height in eels injected with e2 after six and eight times, and eventually reached a minimum level after eight weeks. Using ra- dioimmunoassay of thyroxine (T4),triiodothyronine (T3) in the serum, a slowly decrease of both hor- mones is demonstrated. On the other hand, the TSHβ mRNA level is significantly increased from initial in the high-dose e2 treatment group. The histological structure of the thyroid follicles suggests a hypo- activity, and a sharp decrease of the both hormones is also indicated. These data suggest that the expres- sion of TSHβ mRNA level is increased and thyroid hormone release is depressed by e2, the effects de- pend upon e2 inection period and dose. Furthermore, e2 could not directly influence the TSHβ mRNA expression and, TSH transcription might be controlled by a negative feedback of thyroid hormone.

关键词： Thyroid activity thyroxine (T4) triiodothyronine (T3) Japanese eel RT-PCR