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Effects of temperature and hydric environment on survival of the Panamanian Golden Frog infected with a pathogenic chytrid fungus

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Integrative Zoology 2010年第2期5卷 143-153页

作者： heidi m.BUSTAmANTE Lauren J.LIVO Cynthia CAREY Department of Integrative Physiology University of ColoradoBoulderColoradoUSA

Considerable controversy exists concerning whether or not climate changes(particularly global warming)are causing outbreaks of a lethal amphibian pathogen,the chytrid fungus Batrachochytrium dendrobatidis(Longcore,Pessier&*** 1999).In the present study,groups of Panamanian golden frogs(Atelopus zeteki Dunn,1993),a critically endangered amphibian thought to be nearly extinct in Panama,were exposed to varying dosages of zoospores of Batrachochytrium dendrobatidis,temperatures and hydric environments in order to learn whether this species is susceptible to this pathogen and,if so,how environmental factors affect *** pathogen proved to be highly lethal for *** exposed to a dosage of 100 Bd zoospores survived significantly(Pmate change and the decline of these frogs in the field,but they inform the discussion about how environmental conditions can have an impact on the interaction between a susceptible amphibian and this *** data do not support the contention that rising global temperatures are necessary to cause the death of amphibians infected with this pathogen because the pathogen was equally lethal at 17 as at 23℃,and frogs at the warmer temperature lived significantly longer than those at the cooler one.

关键词： amphibian declines Atelopus zeteki Batrachochytrium dendrobatidis chytridiomycosis climatelinked-epidemic hypothesis

Applied and Environmental Chemistry of Animal manure:A Review

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Pedosphere 2016年第6期26卷 779-816页

作者： Zhongqi HE Paulo H.PAGLIARI heidi m.WALDRIP USDA-ARS Southern Regional Research Center Department of Soil Waterand ClimateUniversity of MinnesotaSouthwest Research and Outreach Center USDA-ARS Conservation and Production Research Laboratory

Animal manure consists of predominantly urine and feces, but also may contain bedding materials, dropped feed, scurf, and other farming wastes. manure is typically applied to soils as fertilizer for agricultural production. The estimated amount of manure produced in 12 major livestock-producing countries is 9 × 10^9 mg of manure annually. manure is rich in plant nutrients. However, manure is also considered as an environmental pollutant when it is over-applied to cropland or following runoff into surface water. manure can also influence global climate change via emissions of methane （CH4） and nitrous oxide （N2O）. Thus, increased and updated knowledge of applied and environmental chemistry of animal manure is needed to shed light on the research and development of animal manure utilization and minimization of its adverse environmental concerns. The advances in basic and applied studies of manure major components, organic matter, phosphorus, and nitrogen, primarily related to US livestock production are summarized in this review. Detailed focus was placed on three notable challenges for future manure research： 1） soil application of animal manure, 2） manure phytate phosphorus, and 3） manure nitrogen availability. This review may contribute to the global effort in sustainable and environmentally sound agriculture by stimulating new ideas and directions in animal manure research, and promoting application of knowledge and insight derived from manure research into improved manure management strategies.

关键词： environmental pollutant fertilizer nitrogen availability organic matter phosphorus phytate plant nutrients

Overlap of concurrent extrahepatic autoimmune diseases is associated with milder disease severity of newly diagnosed autoimmune hepatitis

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Hepatobiliary & Pancreatic Diseases International 2021年第1期20卷 21-27页

作者： Tobias mühling Helmut Rohrbach Wolfgang Schepp felix Gundling Department of Gastroenterology Internal Medicine ⅡUniversity of WürzburgWürzburgGermany Department of Pathology Academic Teaching Hospital BogenhausenTechnical University of MunichMunich 81925Germany Department of Gastroenterology Hepatology and Gastrointestinal OncologyAcademic Teaching Hospital BogenhausenTechnical University of MunichMunich 81925Germany Department of Internal medicine Division of GastroenterologyGastrointestinal Oncology and DiabetologyKemperhof KoblenzKoblenzGermany

Background:Concurrent extrahepatic autoimmune disorders(CEHAID)are frequently observed in autoimmune hepatitis(AIH).It is not clear whether there is any prognostic significance of CEHAID on *** aim of this study was to examine the prognostic impact of CEHAID and the correlation with the disease severity of ***:This study included 65 hospitalized subjects who fulfilled the accepted criteria for AIH during an 8-year period(2009–2016).All records were manually screened for presence of associated autoimmune *** severity of AIH was assessed by liver laboratory tests including the ratio of aspartate aminotransferase to alanine aminotransferase(AST/ALT)and liver ***:Among the enrolled patients,52(80%)were female(median age 61 years,IQR 45–75).Fifty-six(86.2%)were classified as type-1 *** 26(40%)patients at least one additional extrahepatic autoimmune disease was ***-four subjects were referred to our hospital because of acute presentation of AIH(supposed by an acute elevation of hepatic enzymes)for subsequent liver biopsy resulting in initial diagnosis of *** group was stratified into 3 subgroups:(A)AIH alone(n=14);(B)overlap with primary biliary cirrhosis(PBC)/primary sclerosing cholangitis(PSC)(n=11);and(C)with CEHAID(n=9).AST/ALT ratio was the lowest in subgroup C(median 0.64,IQR 0.51–0.94;P=0.023),compared to subgroup A(median 0.91,IQR 0.66–1.10)and subgroup B(median 1.10,IQR 0.89–1.36).Patients with AIH alone showed a trend to the highest grade of fibrosis(mean 2.3;95%CI:1.5–3.0)with no statistical significance compared to subjects with CEHAID(lowest grade of fibrosis;mean 1.5;95%CI:0.2–2.8;P=0.380)whereas the ongoing inflammation was ***:AST/ALT ratio and extent of fibrosis were lower in subjects with AIH and CEHAID,compared to subjects with only ***,the occurrence of CEHAID might be a predictor for lower disease severity of newly diagnosed acute onset AIH,possibly caused by an e

关键词： Autoimmune hepatitis Concurrent extrahepatic autoimmune disease Serum aminotransferase activities

Population differentiation at a regional scale in spadefoot toads： contributions of distance and divergent selective environments

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Current Zoology 2016年第2期62卷 193-206页

作者： Amber m. RICE michael A. mCQUILLAN heidi A. SEEARS Joanna A. WARREN Department of Biological Sciences Lehigh University BethLehem PA 18015 USA

The causes of population differentiation can provide insight into the origins of early barriers to gene flow. Two key drivers of population differentiation are geographic distance and local adaptation to divergent selective environments. When reproductive isolation arises because some populations of a species are under selection to avoid hybridization while others are not, population differentiation and even speciation can result. Spadefoot toad populations Spea multiplicata that are sympatric with a congener have undergone reinforcement. This reinforcement has resulted not only in increased reproductive isolation from the congener, but also in the evolution of reproductive isolation from nearby and distant conspecific allopatric populations. We used multiple approaches to evaluate the contributions of geographic distance and divergent selective environments to population structure across this regional scale in S. multiplicata, based on genotypes from six nuclear microsatellite markers. We compared groups of populations varying in both geographic location and in the presence of a congener. Hierarchical F-statistics and results from cluster analyses and discriminant analyses of principal components all indicate that geographic distance is the stronger contributor to genetic differentiation among S. multiplicata populations at a regional scale. However, we found evidence that adaptation to divergent selective environments also contributes to population structure. Our findings highlight how variation in the balance of evolutionary forces acting across a species＇ range can lead to variation in the relative contributions of geographic distance and local adaptation to population differentiation across different spatial scales.

关键词： cascade reinforcement character displacement reproductive isolation spatial scale Spea multipficata speciation

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中耳传声过程中砧镫关节声损失的研究

中华耳鼻咽喉头颈外科杂志 2005年第7期40卷 505-508页

作者：马芙蓉 Thomas Linder Alex Huber heidi felix Anita Pollak 北京大学第三医院耳鼻咽喉科瑞士苏黎世大学耳鼻咽喉头颈外科

目的为了研究声音在中耳传递过程中在砧镫关节上的声损失,深入了解中耳传声中的机制和方式,并探讨其意义,为中耳手术中听骨链重建,尤其是为耳硬化手术中镫骨赝复物与砧骨长脚的嵌合的理想程度寻找理论依据。方法本试验研究了17个新鲜颞... 详细信息

目的为了研究声音在中耳传递过程中在砧镫关节上的声损失,深入了解中耳传声中的机制和方式,并探讨其意义,为中耳手术中听骨链重建,尤其是为耳硬化手术中镫骨赝复物与砧骨长脚的嵌合的理想程度寻找理论依据。方法本试验研究了17个新鲜颞骨标本。用2个颞骨进行了机械刺激时的磁场矫正。采用激光多普勒振动仪,分别在声刺激和机械刺激下,对15个新鲜颞骨标本进行了研究。首先测量在80dB声刺激(声压级,下同)下镫骨底板的位移,然后在机械刺激条件下得到等同于80dB声刺激的镫骨底板位移以建立试验体系并保证试验体系的准确性。在等同于80dB声刺激的机械刺激条件下,测量10个颞骨标本砧镫关节的声损失。结果在所测量的频率中,砧镫关节上的声损失在3dB以内。结论中耳传声过程中,在砧镫关节上存在着声损失,这种损失是生理性和保护性的。

关键词：中耳关节声砧镫关节机械刺激试验体系刺激条件听骨链重建激光多普勒声刺激骨标本砧骨长脚试验研究手术中其意义赝复物镫骨耳硬化振动仪声压级测量准确性保护性生理性新鲜位移

Imaging resolution of biocatalytic activity using nanoscale scanning electrochemical microscopy

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Nano Research 2018年第8期11卷 4232-4244页

作者： Jase m .Abad Alvaro Y. Tesio EmUiano martinez-Perinan felix Pariente Encamacion Lorenzo Departamento de Qufmica Analftica y Andlisis Instrumental Universidad Aut6noma de Madrid Cantoblanco 28049 Madrid Spain Centro de Investigaci6n y Desarrollo en materiales Avanzados y Almacenamiento de Energfa de Jujuy-CIDmEJu (CONICET-UniversidadNacional de Jujuy) Centro de Desarrollo Tecnol6gico General Savio Av. Martijena s/n 4612-Palpald Jujuy Argentina Instituto madrileno de Estudios Avanzados en Nanociencia (ImDEA-Nanociencia) Campus UAM Cantoblanco 28049 Madrid Spain

Scanning electrochemical microscopy represents a powerful tool for electro（chemical） characterization of surfaces, but its applicability has been limited in most cases at microscale spatial resolution, and the greatest challenge has been the scaling down to the nanoscale for fabrication and the use of nanometer-sized tips. Here, Pt nanoelectrodes with nanometer electroactive area were fabricated and employed for imaging a distribution of gold nanoparticles （AuNPs） and bioelectrocatalytic activity of a redox-active enzyme immobilized on gold surfaces.

关键词： scanning electrochemicalmicroscopy gold nanoparticle redox enzyme nanoelectrode lactate oxidase

Cannabinoids and endocannabinoids as therapeutics for nervous system disorders:preclinical models and clinical studies

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Neural Regeneration Research 2024年第4期19卷 788-799页

作者： R.Scott Duncan Sean m.Riordan matthew C.Gernon Peter Koulen Department of Ophthalmology School of MedicineUniversity of Missouri Department of Biomedical Sciences School of MedicineUniversity of Missouri

Cannabinoids are lipophilic substances derived from Cannabis sativa that can exert a variety of effects in the human *** have been studied in cellular and animal models as well as in human clinical trials for their therapeutic benefits in several human *** of these include central nervous system(CNS)diseases and dysfunctions such as forms of epilepsy,multiple sclerosis,Parkinson’s disease,pain and neuropsychiatric *** addition,the endogenously produced cannabinoid lipids,endocannabinoids,are critical for normal CNS function,and if controlled or modified,may represent an additional therapeutic avenue for CNS *** review discusses in vitro cellular,ex vivo tissue and in vivo animal model studies on cannabinoids and their utility as therapeutics in multiple CNS *** addition,the review provides an overview on the use of cannabinoids in human clinical trials for a variety of CNS *** and endocannabinoids hold promise for use as disease modifiers and therapeutic agents for the prevention or treatment of neurodegenerative diseases and neurological disorders.

关键词： anandamide cannabidiol cannabinoid endocannabinoid epilepsy multiple sclerosis neurodegeneration neuroprotection tetrahydrocannabinol

Improved source assessment of Si,Al and related mineral components to Pm_(10) based on a daily sampling procedure

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Journal of Environmental Sciences 2010年第4期22卷 582-588页

作者： Ge Peng Hans Puxbaum heidi Bauer Nicole Jankowski Yao Shi Chemical Engineering College Ningbo University of Technology Ningbo 315016 China. Institute for Chemical Technologies and Analytics Vienna University of Technology Vienna 1060 Austria College of Environmental and Resource Sciences Zhejiang University Hangzhou 310027 China

Samples obtained from an industrialized valley in the East Alpine region were collected daily for a half year and analyzed using X-ray fluorescence to examine the elements Si, Al, Fe, Ca, mg, Na, K, Zn, P, S and Cl. Some factors affecting the changes of these elements were considered, including time, elemental correlations, weekday, weekend and seasonal changes. Diagnostic analysis provided an insight into a decoupling behavior that occursin siliceous and carbonates minerals. A decrease in Si and Al and an increase in carbonates, Na, K, Zn and P were observed during the cold season. However, a consistently high correlation of Si and Al was observed in all seasons. It was established that such high levels originated from street surface abrasion. The increase in variability and absolute levels of carbonates during the cold season was demonstrated by adding carbonates to the street surface as gritting material to increase the grip on snowy surfaces. A marked increase in Na and Cl was observed in winter which may have been caused by thaw salt that is widely used in winter in Austria. This was associated with a significant increase in K, Zn, and P in the cold season that was the result of domestic space heating with wood. Pm10 levels in December were 12 μ/m^3 and were higher than levels detected in July. It was established that such high levels originated from mineral oxides, wood smoke, and inorganic ionic material（s）.

关键词： particulate matter Pm10 mineral aerosol silicates carbonates street dust wood combustion thaw salt

Adult-to-adult right lobe living donor liver transplantation:Comparison of endoscopic retrograde cholangiography with standard T2-weighted magnetic resonance cholangiography for evaluation of donor biliary anatomy

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World Journal of Gastroenterology 2006年第36期12卷 5820-5825页

作者： Perdita Wietzke-Braun felix Braun Dieter müller Thomas Lorf Burckhardt Ringe Giuliano Ramadori Abteilung für Gastroenterologie und Endokrinologie Georg-August-Universitt Gttingen Germany Klinik für Allgemeine Chirurgie und Thorax-chirurgie Universitt Schleswig-Holstein Campus Kiel Germany Abteilung für Diagnostische Radiologie Georg-August-Universitt Gttingen Germany Klinik für Allgemeine Chirurgie Georg-August-Universitt Gttingen Germany Center for Liver Pancreas and Biliary Disease Drexel University College of Medicine Philadelphia United States

AIm: To compare the value of endoscopic retrograde cholangiography (ERC) and standard T2-weighted magnetic resonance cholangiography (mRC) in the evaluation process as adult-to-adult right lobe living donor liver transplantation (LDLTx) demands a successful outcome, and exact knowledge of the biliary tree is implicated to avoid biliary complications, ***: After starting the LDLTx program, 18 liver transplant candidates were selected for LDLTx by a stepwise evaluation process. ERC and standard T2-weighted mRC were performed to evaluate the biliary system of the donor liver. The anatomical findings of ERC and mRC mapping were compared using the Ohkubo classification. RESULTS: ERC allowed mapping of the whole biliary system in 15/15 (100%) cases, including 14/15 (93.3%) with biliary variants while routine mRC was only accurate in 2/13 (15.4%) cases. mRC was limited in depicting the biliary system proximal of the hepatic bifurcation. Postoperative biliary complications occurred in 2 donors and 8 recipients. Biliary complications were associated with Ohkubo type C, E or G in 6/8 recipients, and 2/3 recipients with biliary leak received a graft with multiple (≥2) bile ducts. CONCLUSION: Pretransplant ERC is safe and superior over standard mRC for detection of biliary variations that occur with a high frequency. However, precise knowledge of biliary variants did not reduce the incidence of postoperative biliary complications.

关键词： Living donor liver transplantation Donors biliary tree Endoscopic retrograde cholangiography magnetic resonance cholangiography