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Long-term monitoring of cycles in Clethrionomys rutilus in the Yukon boreal forest

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Integrative Zoology 2024年第1期19卷 27-36页

作者： Charles J.KREBS Alice J.KENNEY B.Scott GILBERT Rudy boonstra Department of Zoology University of British ColumbiaVancouverBritish ColumbiaCanada Renewable Resources Management Program Yukon UniversityWhitehorseYukonCanada Department of Biological Sciences University of Toronto ScarboroughTorontoOntarioCanada

Baseline studies of small rodent populations in undisturbed ecosystems are *** report here 50 years of mon-itoring and experimentation in Yukon of a dominant rodent species in the North American boreal forest,the red-backed vole Clethrionomys *** voles breed in summer,weigh 20–25 g,and reach a maximum density of 20 to 25 per *** populations have shown consistent 3–4-year cycles for the last 50 years with the only change being that peak densities averaged 8/ha until 2000 and 18/ha since that *** the last 25 years,we have measured food resources,predator numbers,and winter weather,and for 1-year social interactions,to estimate their contribution to changes in the rate of summer increase and the rate of overwinter *** these potential limiting factors could contribute to changes in density,and we measured their relative contributions statistically with multiple *** rate of winter decline in density was related to both food supply and winter *** rate of summer increase was related to summer berry crops and white spruce cone *** measure of predator numbers was related to winter or summer changes in vole *** was a large signal of climate change effects in these *** is no density dependence in summer population growth and only a weak one in winter population *** of our results provide a clear understanding of what generates 3–4-year cycles in these voles,and the major missing piece may be an understanding of social interactions at high density.

关键词： boreal forest climate change density dependence population cycles predation winter severity

Immune mechanisms of vaccine induced protection against chronic hepatitis C virus infection in chimpanzees

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World Journal of Hepatology 2015年第1期7卷 53-69页

作者： Babs E Verstrepen André boonstra Gerrit Koopman Department of Virology Biomedical Primate Research Centre2280GH RijswijkThe Netherlands Department of Gastroenterology and Hepatology Erasmus University Medical Center Rotterdam3015 CE RotterdamThe Netherlands

Hepatitis C virus(HCV) infection is characterized by a high propensity for development of life-long viral persistence. An estimated 170 million people suffer from chronic hepatitis caused by HCV. Currently,there is no approved prophylactic HCV vaccine *** the near disappearance of the most relevant animal model for HCV,the chimpanzee,we review the progression that has been made regarding prophylactic vaccine development against HCV. We describe the results of the individual vaccine evaluation experiments in chimpanzees,in relation to what has been observed in humans. The results of the different studies indicate that partial protection against infection can be achieved,but a clear correlate of protection has thus far not yet been defined.

关键词： Hepatitis C virus Vaccines Chimpanzees Review Prophylactic Antibodies T-cells

Impact of climate change on the small mammal community of the Yukon boreal forest

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Integrative Zoology 2019年第6期14卷 528-541页

作者： Charles J.KREBS Rudy boonstra BScott GILBERT Alice J.KENNEY Stan BOUTIN Department of Zoology University of British ColumbiaVancouverBritish ColumbiaCanada Department of Biological Sciences University of Toronto ScarboroughTorontoOntarioCanada Renewable Resources Management Program Yukon CollegeWhitehorseYukonCanada Department of Biological Sciences University of AlbertaEdmontonAlbertaCanada

Long-term monitoring is critical to determine the stability and sustainability of wildlife populations,and if change has occurred,*** have followed population density changes in the small mammal community in the boreal forest of the southern Yukon for 46 years with density estimates by live trapping on 3-5 unmanipulated grids in spring and *** community consists of 10 species and was responsible for 9%of the energy flow in the herbivore component of this ecosystem from 1986 to 1996,but this increased to 38%from 2003 to *** mammals,although small in size,are large in the transfer of energy from plants to predators and *** species form the bulk of the *** was a shift in the dominant species from the 1970s to the 2000s,with Myodes rutilus increasing in relative abundance by 22%and Peromyscus maniculatus decreasing by 22%.From 2007 to 2018,Myodes comprised 63%of the catch,Peromyscus 20%,and Microtus species 17%.Possible causes of these changes involve climate change,which is increasing primary production in this boreal forest,and an associated increase in the abundance of 3 rodent predators,marten(Martes americana),ermine(Mustela ermine)and coyotes(Canis latrans).Following and understanding these and potential future changes will require long-term monitoring studies on a large scale to measure metapopulation *** small mammal community in northern Canada is being affected by climate change and cannot remain sta*** will be critically dependent on food-web interactions that are species-specific.

关键词： community change long-term study population cycles trophic dynamics voles

Immune aspects of hepatocellular carcinoma:From immune markers for early detection to immunotherapy

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World Journal of Gastrointestinal Oncology 2021年第9期13卷 1132-1143页

作者： Ângelo Z Mattos Jose D Debes Andre boonstra Arndt Vogel Angelo A Mattos Graduate Program in Medicine:Hepatology Federal University of Health Sciences of Porto AlegrePorto Alegre 90050-170Brazil Gastroenterology and Hepatology Unit Irmandade Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90020-090Brazil Department of Medicine Division of Gastroenterology and Infectious DiseasesUniversity of MinnesotaMinneapolisMN 55812United States Department of Gastroenterology and Hepatology Erasmus Medical CenterRotterdam NL-3015The Netherlands Department of Gastroenterology Hepatology and EndocrinologyHannover Medical SchoolHannover 30625Germany

Hepatocellular carcinoma(HCC)is one of the most prevalent cancers and one of the main causes of cancer-related deaths *** HCCs develop in an inflammatory microenvironment,and mounting evidence emphasizes the importance of immune aspects in *** normal physiology,both innate and adaptive immune responses are responsible for eliminating malignantly transformed cells,thus preventing the development of liver ***,in the setting of impaired natural killer cells and exhaustion of T cells,HCC can *** immunogenic features of HCC have relevant clinical *** is a large number of immune markers currently being studied for the early detection of liver cancer,which would be critical in order to improve surveillance ***,novel immunotherapies have recently been proven to be effective,and the combination of atezolizumab and bevacizumab is currently the most effective treatment for advanced *** is expected that in the near future different subgroups of patients will benefit from specific *** better we understand the immune aspects of HCC,the greater the benefit to patients through surveillance aiming for early detection of liver cancer,which allows for curative treatments,and,in cases of advanced disease,through the selection of the best possible therapy for each individual.

关键词： Hepatocellular carcinoma Immunology Hepatocarcinogenesis Surveillance Biomarker Immunotherapy

Impact of rewilding,species introductions and climate change on the structure and function of the Yukon boreal forest ecosystem

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Integrative Zoology 2018年第2期13卷 123-138页

作者： Rudy boonstra Stan BOUTIN Thomas S.JUNG Charles J.KREBS Shawn TAYLOR Department of Biological Sciences University of Toronto ScarboroughTorontoOntarioCanada Department of Biological Sciences University of AlbertaEdmontonAlbertaCanada Department of Environment Government of YukonWhitehorseYukonCanada Department of Zoology University of British ColumbiaVancouverBritish ColumbiaCanada

Community and ecosystem changes are happening in the pristine boreal forest ecosystem of the Yukon for 2 ***,climate change is affecting the abiotic environment(temperature,rainfall and growing season)and driving changes in plant productivity and predator-prey ***,simultaneously change is occurring because of mammal species reintroductions and *** key ecological question is the impact these faunal changes will have on trophic *** productivity in the boreal forest is increasing because of climatic warming,but plant species composition is unlikely to change significantly during the next 50-100 *** 9-10-year population cycle of snowshoe hares will persist but could be reduced in amplitude if winter weather increases predator hunting *** rodents have increased in abundance because of increased vegetation *** ground squirrels have disappeared from the forest because of increased predator hunting efficiency associated with shrub *** have occurred for 2 reasons:human reintroductions of large ungulates and natural recolonization of mammals and birds extending their geographic *** deliberate rewilding of wood bison(Bison bison)and elk(Cervus canadensis)has changed the trophic structure of this boreal ecosystem very *** natural range expansion of mountain lions(Puma concolor),mule deer(Odocoileus hemionus)and American marten(Martes americana)should have few ecosystem *** potential changes will require long-term monitoring studies and experiments on a scale we rarely deem *** affected by climate change,species reintroductions and human alteration of habitats cannot remain stable and changes will be critically dependent on food web interactions.

关键词： community stability introduced species population cycles trophic dynamics

Mechanisms of Accelerated Liver Fibrosis Progression during HIV Infection

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Journal of Clinical and Translational Hepatology 2016年第4期4卷 328-335页

作者： Jose D.Debes Paul R.Bohjanen Andre boonstra Department of Medicine Division of Infectious Disease and International Medicine University of MinnesotaMinneapolis MN USA Department of Gastroenterology and Hepatology Erasmus MC Rotterdam The Netherlands

With the introduction of antiretroviral therapy (ART),a dramatic reduction in HIV-related morbidity and mortality has been ***,it is now becoming increasingly clear that liver-related complications,particularly rapid fibrosis development from ART as well as from the chronic HIV infection itself,are of serious concern to HIV *** pathophysiology of liver fibrosis in patients with HIV is a multifactorial process whereby persistent viral replication,and bacterial translocation lead to chronic immune activation and inflammation,which ART is unable to fully suppress,promoting production of fibrinogenic mediators and *** addition,mitochondrial toxicity,triggered by both ART and HIV,contributes to intrahepatic damage,which is even more severe in patients co-infected with viral *** recent years,new insights into the mechanisms of accelerated fibrosis and liver disease progression in HIV has been obtained,and these are detailed and discussed in this review.

关键词： HIV Liver fibrosis Mitochondrial toxicity Bacterial translocation

Current impact of viral hepatitis on liver cancer development: The challenge remains

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World Journal of Gastroenterology 2021年第24期27卷 3556-3567页

作者： Ângelo Zambam de Mattos Jose D Debes Andre boonstra Ju-Dong Yang Domingo C Balderramo Giovana D P Sartori Angelo Alves de Mattos Department of Gastroenterology and Hepatology Federal University of Health Sciences of Porto AlegrePorto Alegre 90020-090Brazil Gastroenterology and Hepatology Unit Irmandade Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90050-170Brazil Department of Medicine Division of Gastroenterology and Infectious DiseasesUniversity of MinnesotaMinneapolisMN 55455United States Department of Gastroenterology and Hepatology Erasmus Medical CenterRotterdam NL-3015Netherlands Division of Digestive and Liver Diseases Department of MedicineCedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Gastroenterology Hospital Privado Universitario de CórdobaCórdoba 5016Argentina Department of Medicine Instituto Universitario de Ciencias Biomédicas de CórdobaCórdoba 5016Argentina Department of Internal Medicine Hospital Nossa Senhora da ConceiçãoPorto Alegre 91350-200Brazil

Chronic infections due to hepatitis B and hepatitis C viruses are responsible for most cases of hepatocellular carcinoma(HCC)worldwide,and this association is likely to remain during the next ***,viral hepatitis-related HCC imposes an important burden on public health in terms of disability-adjusted life *** order to reduce such a burden,some major challenges must be *** vaccination against hepatitis B virus,especially in the neonatal period,is probably the most relevant primary preventive measure against the development of ***,considering the large adult population already infected with hepatitis B and C viruses,it is also imperative to identify these individuals to ensure their access to *** hepatitis B and C currently have highly effective therapies,which are able to diminish the risk of development of liver ***,it is essential for individuals at high-risk of HCC to be included in surveillance programs,so that tumors are detected at an early *** with hepatitis B or C and advanced liver fibrosis or cirrhosis benefit from being followed in a surveillance *** hepatitis B virus is oncogenic and capable of leading to liver cancer even in individuals with early stages of liver fibrosis,other high-risk groups of patients with hepatitis B are also candidates for *** effort is required concerning these strategies in order to decrease the incidence and the mortality of viral hepatitis-related HCC.

关键词： Hepatitis B virus Hepatitis C virus Hepatocellular carcinoma Epidemiology Vaccination Surveillance

Near-infrared fluorescence sentinel lymph node detection in gastric cancer: A pilot study

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World Journal of Gastroenterology 2016年第13期22卷 3644-3651页

作者： Quirijn RJG Tummers Leonora SF Boogerd Wobbe O de Steur Floris PR Verbeek Martin C boonstra Henricus JM Handgraaf John V Frangioni Cornelis JH van de Velde Henk H Hartgrink Alexander L Vahrmeijer Department of Surgery Leiden University Medical Center 2333 ZA Leiden The Netherlands Division of Hematology/Oncology Department of Medicine and Department of Radiology Beth Israel Deaconess Medical Center Boston MA 02215 United States Curadel LLC 377 Plantation Street Worcester MA 01605 United States

AIM: To investigate feasibility and accuracy of near-infrared fluorescence imaging using indocyanine green: nanocolloid for sentinel lymph node (SLN) detection in gastric ***: A prospective, single-institution, phase I feasibility trial was conducted. Patients suffering from gastric cancer and planned for gastrectomy were included. During surgery, a subserosal injection of 1.6 mL ICG:Nanocoll was administered around the tumor. NIR fluorescence imaging of the abdominal cavity was performed using the Mini-FLARE™ NIR fluorescence imaging system. Lymphatic pathways and SLNs were visualized. Of every detected SLN, the corresponding lymph node station, signal-to-background ratio and histopathological diagnosis was determined. Patients underwent standard-of-care gastrectomy. Detected SLNs outside the standard dissection planes were also resected and ***: Twenty-six patients were enrolled. Four patients were excluded because distant metastases were found during surgery or due to technical failure of the injection. In 21 of the remaining 22 patients, at least 1 SLN was detected by NIR Fluorescence imaging (mean 3.1 SLNs; range 1-6). In 8 of the 21 patients, tumor-positive LNs were found. Overall accuracy of the technique was 90% (70%-99%; 95%CI), which decreased by higher pT-stage (100%, 100%, 100%, 90%, 0% for respectively Tx, T1, T2, T3, T4 tumors). All NIR-negative SLNs were completely effaced by tumor. Mean fluorescence signal-to-background ratio of SLNs was 4.4 (range 1.4-19.8). In 8 of the 21 patients, SLNs outside the standard resection plane were identified, that contained malignant cells in 2 ***: This study shows successful use of ICG:Nanocoll as lymphatic tracer for SLN detection in gastric cancer. Moreover, tumor-containing LNs outside the standard dissection planes were identified.

关键词： Gastric cancer Sentinel lymph node Near-infrared fluorescence imaging Image-guided surgery Indocyanine green

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世界硫资源的需求与供给述评

资源开发与市场 1992年第4期 308-310页

作者： boonstra ER 卢永记

过去10年,世界硫的消费量增长了900万t,1988年的消费量增加到6000万t,年增长率约为1.5％;其中化肥耗硫量为3500万t,非化肥耗硫量为2500万t。全世界用于生产磷酸盐和磷肥的硫占其总消费量的1/2以上;因此,磷肥业控制了硫的生产。据预测,2... 详细信息

过去10年,世界硫的消费量增长了900万t,1988年的消费量增加到6000万t,年增长率约为1.5％;其中化肥耗硫量为3500万t,非化肥耗硫量为2500万t。全世界用于生产磷酸盐和磷肥的硫占其总消费量的1/2以上;因此,磷肥业控制了硫的生产。据预测,2000年以前世界磷肥需求量的年增长率为2％以上(图1),发展中国家的增长率最高、约为4％,集中计划经济国家略高于世界平均水平,发

关键词：消费量磷肥无机肥料总产量弗拉斯硫资源需求