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The agents of natural genome editing

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Journal of Molecular Cell Biology 2011年第3期3卷 181-189页

作者： guenther Witzany Telos–Philosophische Praxis Vogelsangstraße 18cA-5111-BuermoosAustria

The DNA serves as a stable information storage medium and every protein which is needed by the cell is produced from this blueprint via an RNA intermediate *** recently it was found that an abundance of various RNA elements cooperate in a variety of steps and substeps as regulatory and catalytic units with multiple competencies to act on RNA *** genome editing on one side is the competent agent-driven generation and integration of meaningful DNA nucleotide sequences into pre-existing genomic content arrangements,and the ability to(re-)combine and(re-)regulate them according to context-dependent(***)purposes of the host *** genome editing on the other side designates the integration of all RNA activities acting on RNA transcripts without altering DNA-encoded *** we take the genetic code seriously as a natural code,there must be agents that are competent to act on this code because no natural code codes itself as no natural language speaks *** code editing agents,viral and subviral agents have been suggested because there are several indicators that demonstrate viruses competent in both RNA and DNA natural genome editing.

关键词： persistent virus repetitive element transposable element cooped adaptation riboagent non-coding RNA

Induction of ultra-morphological features of apoptosis in mature and immature sperm

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Asian Journal of Andrology 2017年第5期19卷 533-537页

作者： Sonja Grunewald guenther Fitzl Christopher Springsguth Department of Dermatology Venerology and Allergology University Hospital Leipzig Leipzig Germany Institute of Anatomy University of Leipzig Leipzig Germany

There is a fundamental body of evidence suggesting that activated apoptosis signaling in ejaculated human sperm negatively influences their fertilization potential. However, it is still controversial whether this apoptotic signaling is a relic of an abortive apoptosis related to spermatogenesis or if it should be regarded as a functional preformed pathway in mature sperm leading to stereotypical morphological changes reflecting nuclear disassembly. To address this question, apoptosis was induced using betulinic acid in mature and immature ejaculated human sperm enriched by density gradient centrifugation. Execution of apoptosis was monitored by observing ultra-morphological changes via transmission electron microscopy. Typical morphological signs of apoptosis in somatic cells include plasma membrane blebbing with the formation of apoptotic bodies, impaired mitochondrial integrity, defects of the nuclear envelope, and nuclear fragmentation; these morphologies have also been observed in human sperm. In addition, these apoptotic characteristics were more frequent in immature sperm compared to mature sperm. Following betulinic acid treatment, apoptosis-related morphological changes were induced in mature sperm from healthy donors. This effect was much less pronounced in immature sperm. Moreover, in both fractions, the betulinic acid treatment increased the percentage of acrosome-reacted sperm. The results of our ultra-morphological study prove the functional competence of apoptosis in mature ejaculated human sperm. The theory of a sole abortive process may be valid only for immature sperm. The induction of the acrosome reaction by stimulating apoptosis might shed light on the biological relevance of sperm apoptosis.

关键词： apoptosis electron microscopy human morphology sperm

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急性胰腺炎的外科治疗

中华外科杂志 2001年第4期39卷 329-331页

作者： Hans guenther Beger Bettina Rau Rainer Isenmann Jens Mayer 刘斌吴在德 Professor of Surgery 同济医科大学同济医院

100年前,波士顿的Reginald　Fitz　认为,急性胰腺炎的严重程度主要取决于炎症及其相关形态学变化的程度。急性胰腺炎的病程涉及几个相关器官及其临床、病理、放射学、生化和细菌学检查结果,每种变化都要求有特殊的治疗方法。临床表现包... 详细信息

100年前,波士顿的Reginald　Fitz　认为,急性胰腺炎的严重程度主要取决于炎症及其相关形态学变化的程度。急性胰腺炎的病程涉及几个相关器官及其临床、病理、放射学、生化和细菌学检查结果,每种变化都要求有特殊的治疗方法。临床表现包括轻度的局限性疾病、感染形成及由此所致的严重的局限性和全身性并发症。相应的病理变化包括限制性肠性水肿，至胰腺及周围组织坏死,直至累及远处器官。　　　　

关键词：急性胰腺炎外科手术感染病死率

Microwave-assisted combustion to produce benzene polycarboxylic acids as molecular markers for biochar identification and quantification

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Biochar 2021年第4期3卷 407-418页

作者： Bruno Glaser Marie guenther Heike Maennicke Tobias Bromm Institute of Agricultural and Nutritional Sciences Soil BiogeochemistryMartin Luther University Halle-Wittenbergvon-Seckendorff-Platz 306120 HalleGermany

Biochar is a promising carbon dioxide removal(CDR)technology for climate change *** procedures for its determination are lengthy,labor-intensive,and difficult to *** polycarboxylic acids(BPCA)are the most promising molecular markers for identification and quantification of biochar and its quality as they specifically represent the stable polyaromatic backbone of ***,using the BPCA method,its stability and,thus,its C sequestration potential could be used for CDR *** current BPCA method relies on a specific high-pressure digestion apparatus,which is not available around the ***,the aims of the present work were(i)to compare the conventional high-pressure nitric acid oxidation with a microwave-assisted digestion technique and optimize the oxidation conditions in such a way that previous results are comparable with future ones,and(ii)to significantly reduce the digestion time of soil samples of 8 h and to develop a suitable routine method that produces comparable and reproducible *** this purpose,soil and control sample series were prepared for different *** results were compared with the values of the conventional method both for individual samples and for the whole dataset *** ensure the representative-ness of the results,in addition to various soil samples with different properties,we included two reference materials into our data set,one without biochar(wheat flour)and a biochar *** results showed that conventional nitric acid oxidation in the BPCA determination at 170°C and 8 h can be substituted by digestion in a microwave reaction system(CEM Mars6)at 190°C and 1 *** results further showed that this condition needs to be strictly matched,because,otherwise,over-or underestimation of biochar quantity and/or quality will be the *** goal of a less time-consuming BPCA extrac-tion from soil samples was achieved by reducing the extraction t

关键词： Biochar Black carbon Pyrogenic carbon Analysis Molecular marker Microwave-assisted combustion

Is the speed of adjusting to environmental change condition dependent?An experiment with house mice(Mus musculus)

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Current Zoology 2024年第3期70卷 350-360页

作者： Karem Lopez-Hervas Neelam Porwal Mathilde Delacoux Alexandros Vezyrakis Anja guenther RG Behavioural Ecology of Individual Differences Max Planck Institute for Evolutionary Biology24306 PlönGermany Department of Evolutionary Biology Faculty of BiologyAdam Mickiewicz UniversityWieniawskiego 161-712 PoznańPoland Department for Collective Behaviour Max Planck Institute of Animal Behaviour78464 ConstanceGermany Centre for the Advanced Study of Collective Behaviour University of Konstanz78464 ConstanceGermany Animal Ecology Institute for Biochemistry and BiologyUniversity of Potsdam14469 PotsdamGermany

Environmental conditions change constantly either by anthropogenic perturbation or naturally across space and ***,a change in behavior is the frst response to changing *** fexibility can potentially improve an organism’s chances to survive and ***,we lack an understanding on the time-scale such behavioral adjustments need,how they actually affect reproduction and survival and whether behavioral adjustments are suffcient in keeping up with changing *** used house mice(Mus musculus)to test whether personality and life-history traits can adjust to an experimentally induced food-switch fexibly in adulthood or by intergenerational plasticity,that is,adjustments only becoming visible in the offspring *** lived in 6 experimental populations of semi-natural environments either on high or standard quality food for 4 *** showed previously that high-quality food induced better conditions and a less risk-prone ***,we tested whether the speed and/or magnitude of adjustment shows condition-dependency and whether adjustments incur ftness ***-history but not personality traits reacted fexibly to a food-switch,primarily by a direct reduction of reproduction and sloweddown *** whose parents received a food-switch developed a more active stress-coping personality and gained weight at a slower rate compared with their respective ***,the modulation of most traits was condition-dependent,with animals previously fed with high-quality food showing stronger *** study highlights that life-history and personality traits adjust at different speed toward environmental change,thus,highlighting the importance of the environment and the mode of response for evolutionary models.

关键词： animal personality context dependence environmental change Match-mismatch non-genetic inheritance phenotypic flexibility phenotypic plasticity

Numerical model to quantify biogenic volatile organic compound emissions:The Pearl River Delta region as a case study

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Journal of Environmental Sciences 2016年第8期28卷 72-82页

作者： Xuemei Wang Shuping Situ Weihua Chen Junyu Zheng Alex guenther Qi Fan Ming Chang School of Environmental Science and Engineering Sun Yat-Sen University Foshan Environmental Monitoring Center School of Environment and Energy South China University of Technology Department of Earth System Science University of California

This article compiles the actual knowledge of the biogenic volatile organic compound（BVOC） emissions estimated using model methods in the Pearl River Delta（PRD） region, one of the most developed regions in China. The developed history of BVOC emission models is presented briefly and three typical emission models are introduced and compared. The results from local studies related to BVOC emissions have been summarized. Based on this analysis, it is recommended that local researchers conduct BVOC emission studies systematically, from the assessment of model inputs, to compiling regional emission inventories to quantifying the uncertainties and evaluating the model results. Beyond that,more basic researches should be conducted in the future to close the gaps in knowledge on BVOC emission mechanisms, to develop the emission models and to refine the inventory results. This paper can provide a perspective on these aspects in the broad field of research associated with BVOC emissions in the PRD region.

关键词： Biogenic volatile organic compound Pearl River Delta Emission mode Emission inventory

Tissue-specific Gene Expression Changes Are Associated with Aging in Mice

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Genomics, Proteomics & Bioinformatics 2020年第4期18卷 430-442页

作者： Akash Srivastava Emanuel Barth Maria A.Ermolaeva Madlen guenther Christiane Frahm Manja Marz Otto W.Witte Hans-Berger Department of Neurology University Hospital JenaFriedrich Schiller University Jena07747 JenaGermany Bioinformatics/High Throughput Analysis Friedrich Schiller University Jena07743 JenaGermany FLI Leibniz Institute for Age Research 07745 JenaGermany

Aging is a complex process that can be characterized by functional and cognitive decline in an individual. Aging can be assessed based on the functional capacity of vital organs and their intricate interactions with one another. Thus, the nature of aging can be described by focusing on a specific organ and an individual itself. However, to fully understand the complexity of aging,one must investigate not only a single tissue or biological process but also its complex interplay and interdependencies with other biological processes. Here, using RNA-seq, we monitored changes in the transcriptome during aging in four tissues(including brain, blood, skin and liver) in mice at9 months, 15 months, and 24 months, with a final evaluation at the very old age of 30 *** identified several genes and processes that were differentially regulated during aging in both tissue-dependent and tissue-independent manners. Most importantly, we found that the electron transport chain(ETC) of mitochondria was similarly affected at the transcriptome level in the four tissues during the aging process. We also identified the liver as the tissue showing the largest variety of differentially expressed genes(DEGs) over time. Lcn2(Lipocalin-2) was found to be similarly regulated among all tissues, and its effect on longevity and survival was validated using its orthologue in Caenorhabditis elegans. Our study demonstrated that the molecular processes of aging are relatively subtle in their progress, and the aging process of every tissue depends on the tissue’s specialized function and environment. Hence, individual gene or process alone cannot be described as the key of aging in the whole organism.

关键词： Aging RNA-seq analysis Inflammaging Electron transport chain Tissue aging

Impacts of Weather Conditions Modified by Urban Expansion on Surface Ozone: Comparison between the Pearl River Delta and Yangtze River Delta Regions

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Advances in Atmospheric Sciences 2009年第5期26卷 962-972页

作者：王雪梅陈飞吴志勇张美根 Mukul TEWARI Alex guenther Christine WIEDINMYER School of Environmental Science and Engineering Sun Yat-sen University National Center for Atmospheric Research Institute of Atmospheric Physics Chinese Academy of Sciences

In this paper, the online weather research and forecasting and chemistry （WRF-Chem） model is used to explore the impacts of urban expansion on regional weather conditions and its implication on surface ozone concentrations over the Pearl River Delta（PRD） and Yangtze River Delta（YRD） regions. Two scenarios of urban maps are used in the WRF-Chem to represent the early 1990s （pre-urbanization） and the current urban distribution in the PRD and the YRD. Month-long simulation results using the above land-use scenarios for March 2001 show that urbanization increases both the day- and night-time 2-m temperatures by about 0.6℃and 1.4℃, respectively. Daytime reduction in the wind speed by about 3.0 m s-1 is larger than that for the nighttime （0.5 to 2 m s-1）. The daytime increase in the PBL height （〉 200 m） is also larger than the nighttime （50-100 m）. The meteorological conditions modified by urbanization lead to detectable ozone-concentration changes in the PRD and the YRD. Urbanization increases the nighttime surface-ozone concentrations by about 4.7%-8.5% and by about 2.9%-4.2% for the daytime. In addition to modifying individual meteorological variables, urbanization also enhances the convergence zones, especially in the PRD. More importantly, urbanization has different effects on the surface ozone for the PRD and the YRD, presumably due to their urbanization characteristics and geographical locations. Even though the PRD has a smaller increase in the surface temperature than the YRD, it has （a） weaker surface wind speed, （b） smaller increase in PBL heights, and （c） stronger convergence zones. The latter three factors outweighed the temperature increase and resulted in a larger ozone enhancement in the PRD than the YRD.

关键词： urbanization Pearl River Delta (PRD) Yangtze River Delta (YRD) surface ozone concentrations WRF-Chem

Drag on Hydroid-Fouled Nets – An Experimental Approach

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China Ocean Engineering 2015年第3期29卷 369-389页

作者： Pl LADER David W. FREDRIKSSON Jana guenther Zsolt VOLENT Nina BLOCHER David KRISTIANSEN Lars GANSEL Jud DECEW SINTEF Fisheries and Aquaculture United States Naval Academy University of New Hampshire

The present study investigated the drag increase on aquaculture nets due to biofouling of the colonial hydroid Ectopleura larynx. It had two main parts： firstly the growth characteristics of E. larynx were investigated by use of field tests at a Norwegian aquaculture site; secondly the hydrodynamic drag on the fouled twines was studied in a towing tank by using fabricated models of net twines with artificial hydroid fouling. In the field tests, the growth of the hydroids was first measured after three weeks of immersion and then again after six weeks. During this interval, the density of hydroids and the thickness of the hydroid stem were almost constant（1.4 hydroids/mm and 0.29 mm, respectively）, while the average length of the hydroids increased from 6.4 to 11.2 mm. The hydroid length followed a Rayleigh distribution, while the thickness was normal（Gaussian） distributed. Replicas of twines with three different levels of hydroid growth were made（1.5 hydroids/mm twine, hydroid length 9 mm, 16 mm and 20 mm）, and the drag on these twines was measured at different towing velocities（0.1 to 1.4 m/s） and with different twine configurations. For the twine with the shortest hydroids（9 mm）, the drag was from 1.5 times（Re=4000） to 2.2 times（Re=1000） the drag on a clean twine. For the longest hydroids（21 mm）, the drag was 2 times and 3.8 times, respectively.

关键词： hydroid biofouling aquaculture net hydrodynamic drag