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Steroidal scaffold decorations in Solanum alkaloid biosynthesis

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molecular Plant 2024年第8期17卷 1236-1254页

作者： Rosalind Lucier mohamed O.Kamileen Yoko Nakamura Sofiia Serediuk Ranjit Barbole jens Wurlitzer maritta Kunert Sarah Heinicke Sarah E.O'Connor Prashant d.Sonawane department of Natural Product Biosynthesis Max Planck Institute for Chemical Ecology07745 JenaGermany Research Group Biosynthesis and NmR Max Planck Institute for Chemical Ecology07745 JenaGermany Biochemical Sciences division CSIR-National Chemical LaboratoryPune 411008MaharashtraIndia

Steroidal glycoalkaloids(SGAs)are specialized metabolites produced by hundreds of Solanum species,including important vegetable crops such as tomato,potato,and *** it has been known that SGAs play important roles in defense in plants and“anti-nutritional"effects(e.g.,toxicity and bitterness)to humans,many of these molecules have documented anti-cancer,anti-microbial,antiinflammatory,anti-viral,and anti-pyretic *** these,α-solasonine andα-solamargine isolated from black nightshade(Solanum nigrum)are reported to have potent anti-tumor,anti-proliferative,and anti-inflammatory ***,α-solasonine andα-solamargine,along with the core steroidal aglycone solasodine,are the most widespread SGAs produced among the Solanum ***,it is still unknown how plants synthesize these bioactive steroidal *** comparative metabolomictranscriptome-guided approach,biosynthetic logic,combinatorial expression in Nicotiana benthamiana,and functional recombinant enzyme assays,here we report the discovery of 12 enzymes from *** that converts the starting cholesterol precursorto solasodine aglycone,and the downstreamα-solasonine,α-solamargine,and malonyl-solamargine SGA *** further identified six enzymes from cultivated eggplant that catalyze the production ofα-solasonine,α-solamargine,and malonyl-solamargine SGAs from solasodine aglycone via glycosylation and atypical malonylation *** work provides the gene tool box and platform for engineering the production of high-value,steroidal bioactive molecules inheterologoushosts usingsyntheticbiology.

关键词： steroidal glycoalkaloids Solanum biosynthetic pathway α-solamargine malonyl-solamargine specialized metabolites

metabolic collaboration between cells in the tumor microenvironment has a negligible effect on tumor growth

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The Innovation 2024年第2期5卷 107-114页

作者： Johan Gustafsson Fariba Roshanzamir Anders Hagnestål Sagar m.Patel Oseeyi I.daudu donald F.Becker Jonathan L.Robinson jens Nielsen department of Life Sciences Chalmers University of TechnologySE-41296 GothenburgSweden Hagnesia AB SE-43854 HindåsSweden department of Biochemistry and Redox Biology Center University of Nebraska-LincolnLincolnNE 68588USA BioInnovation Institute DK2200 CopenhagenDenmark

The tumor microenvironment is composed of a complex mixture of different cell types interacting under conditions of nutrient deprivation,but the metabolism therein is not fully understood due to difficulties in measuring metabolic fluxes and exchange of metabolites between different cell types in ***-scale metabolic modeling enables estimation of such exchange fluxes as well as an opportunity to gain insight into the metabolic behavior of individual cell ***,we estimated the availability of nutrients and oxygen within the tumor microenvironment using concentration measurements from blood together with a metabolite diffusion *** addition,we developed an approach to efficiently apply enzyme usage constraints in a comprehensive metabolic model of human *** combined modeling reproduced severe hypoxic conditions and the Warburg effect,and we found that limitations in enzymatic capacity contribute to cancer cells’preferential use of glutamine as a substrate to the citric acid ***,we investigated the common hypothesis that some stromal cells are exploited by cancer cells to produce metabolites useful for the cancer *** identified over 200 potential metabolites that could support collaboration between cancer cells and cancer-associated fibroblasts,but when limiting to metabolites previously identified to participate in such collaboration,no growth advantage was *** work highlights the importance of enzymatic capacity limitations for cell behaviors and exemplifies the utility of enzyme-constrained models for accurate prediction of metabolism in cells and tumor microenvironments.

关键词： metabolism effect limitations

Effect of viscosity on the avalanche dynamics and flow transition of wet granular matter

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Particuology 2021年第6期19卷 64-75页

作者： jens H.Kasper Vanessa magnanimo Sjoerd d.m.de Jong Arjan Beek Ahmed Jarray multi-Scale mechanics(mSm) Thermal and Fluid EngineeringFaculty of Engineering Technology.University ofTwenteP.O.Box 2177500 AE EnschedeThe Netherlands Construction management and Engineering(CmE) Faculty of Engineering TechnologyUniversity ofTwenteP.O.Box 2177500 AE EnschedeThe Netherlands

The dynamic behaviour of granular flows is important in geo-mechanics and industrial applications,yet poorly *** studied the effects of liquid viscosity and particle size on the dynamics of wet granular material flowing in a slowly rotating drum,in order to detect the transition from the avalanching to the continuous flow regime.A discrete element method(dEm)model,in which contact forces and cohesive forces were considered,was employed to simulate this flow *** model was validated experimentally,using glass beads in a wooden drum and water–glycerol mixtures to tune the liquid *** dEm simulations showed comparable results to the experiments in terms of average slope angle and avalanche *** observed that the avalanche amplitude,flow layer velocity and granular temperature decrease as the liquid viscosity *** effect is more pronounced for smaller sized *** increase in viscous forces causes the flowing particles to behave as a bulk,pushing the free surface towards a convex *** addition,avalanches become less pronounced and the granular flow transitions from the avalanching regime to the continuous *** avalanching flow regime is marked by intermittent rigid body movement of the particulate bed and near-zero drops in the granular temperature,while no rigid body movement of the bed occurs in the continuous flow *** identified the avalanching-continuous flow transition region as a function of a dimensionless granular Galileo number.

关键词： Granular avalanche Transition Cohesion Viscosity Rotary drum dEm

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利用择形分子筛异构化亚甲基二苯胺

Chinese Journal of Catalysis 2024年第7期62卷 124-130页

作者： Sam Van minnebruggen Ka Yan Cheung Trees de Baerdemaeker Niels Van Velthoven matthias degelin Galahad O’Rourke Hiroto Toyoda Andree Iemhoff Imke muller Andrei-Nicolae Parvulescu Torsten mattke jens Ferbitz 吴勤明肖丰收 Toshiyuki Yokoi Nils Bottke dirk de Vos 巴斯夫股份有限公司膜分离、吸附、催化和光谱学可持续解决方案中心(cmACS) 比利时巴斯夫股份有限公司研究组德国东京工业大学纳米空间催化研究所横滨日本浙江大学化学系浙江杭州310028

亚甲基二苯胺(mdA)被广泛用作生产聚氨酯和聚异氰脲酸酯的中间体.然而,当前mdA的生产工艺在控制(4,4’/(2,4’+2,2’))异构体比例方面还存在局限.其中,4,4’-mdA被认为是最有价值的异构体.尽管2,4'-mdA在市场上也有一定的需求,但如果能... 详细信息

亚甲基二苯胺(mdA)被广泛用作生产聚氨酯和聚异氰脲酸酯的中间体.然而,当前mdA的生产工艺在控制(4,4’/(2,4’+2,2’))异构体比例方面还存在局限.其中,4,4’-mdA被认为是最有价值的异构体.尽管2,4'-mdA在市场上也有一定的需求,但如果能将其有效地转化为4,4'-mdA,将能显著提升其附加值.本文在使用苯胺的条件下,利用β分子筛等催化剂,通过双分子机制,可以选择性地将2,4'-mdA异构化为4,4'-mdA.尽管实验显示,多种酸性沸石具有较高的异构化活性,但mCm-68(具有mSE拓扑结构)的催化性能尤为出色,它不仅展现出高异构化活性,而且具有很好的选择性.mCm-68主要催化2,4'-mdA异构化为4,4'-mdA,而2,2'-mdA和低聚物的形成则可以忽略不计.本文还深入探讨了该择形作用的原因,并详细研究了酸位置在mSE分子筛孔道限制中的关键作用.

关键词：铝分布多相催化异构化亚甲基二苯胺聚氨酯择形

Pancreatic panniculitis and elevated serum lipase in metastasized acinar cell carcinoma of the pancreas: A case report and review of literature

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World Journal of Clinical Cases 2020年第21期8卷 5304-5312页

作者： Rainer Christoph miksch Tobias S Schiergens maximilian Weniger matthias Ilmer Philipp m Kazmierczak markus O Guba martin K Angele jens Werner Jan G d'Haese department of General Visceraland Transplantation SurgeryLudwig-Maximilians-University MunichMunich 81377BavariaGermany department of General Visceral Transplantat Vasc&Thorac Surg Campus GrosshadernUniversity of MunichMunich 81377Germany department of General Ludwig Maximilians-University(LMU)Munich 81377Germany department of Radiology Ludwig-Maximilians-University MunichMunich 81377Germany department of Surgery University of MunichKlinikum GrosshadernMunich University HospitalMunich 81377Germany department of General University of MunichKlinikum GrosshadernHospital of the University of MunichMunich 81377Germany department of General Klinikum Univ MunchenKlin Allgemeine Viszeral Transplantat Gefass&ThStandort GrosshadernLudwig-Maximilians-University(LMU)Munich 81377Germany

BACKGROUNd Pancreatic panniculitis is an extremely rare condition associated with different underlying pancreatic disorders and characterized by subcutaneous fat necrosis induced by elevated serum lipase *** lesions usually affect the lower extremities and may precede abdominal symptoms of pancreatic *** cell carcinoma(ACC)of the pancreas is a rare pancreatic neoplasm,accounting for only 1%-2%of pancreatic tumors in *** present the case of a 72-year-old man with ACC of the pancreatic head and synchronous liver *** the primary tumor and liver metastases were *** lipase was elevated before surgery and decreased to normal *** serum lipase levels at follow-up led to the diagnosis of hepatic *** disease progression was then accompanied by pancreatic panniculitis,with subcutaneous fat necrosis and acute *** the best of our knowledge,only 4 cases have been reported in the literature and each showed a similar association of serum lipase levels with pancreatic panniculitis and progression of *** Clinical symptoms and progression of ACC may correlate with serum lipase levels,suggesting potential usefulness as a follow-up biomarker.

关键词： Pancreatic panniculitis Lipase Acinar cell carcinoma Pancreatic cancer Case report

A comparison of conventional and computer-assisted semen analysis.（CRISmAS software） using samples from 166 young danish men

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Asian Journal of Andrology 2011年第3期13卷 453-458,513页

作者： Anne Vested Cecilia H Ramlau-Hansen jens P Bonde Ane m Thulstrup Susanne L Kristensen Gunnar Toft danish Ramazzini Center Department of Occupational Medicine Aarhus University Hospital DK-8000 Aarhus C Denmark department of Occupational and Environmental medicine Copenhagen University Hospital Bispebjerg DK-2400 Copenhagen NV Denmark

The aim of the present study was to compare assessments of sperm concentration and sperm motility analysed by conventional semen analysis with those obtained by computer-assisted semen analysis （CASA）（Copenhagen Rigshospitalet Image House Sperm motility Analysis System （CRISmAS） 4.6 software） using semen samples from 166 young danish men. The CRISmAS software identifies sperm concentration and classifies spermatozoa into three motility categories. To enable comparison of the two methods, the four motility stages obtained by conventional semen analysis were, based on their velocity classifications, divided into three stages, comparable to the three CRISmAS motility categories： rapidly progressive （A）, slowly progressive （B） and non-progressive （C＋ d）. differences between the two methods were large for all investigated parameters （P〈0.001）. CRISmAS overestimated sperm concentration and the proportion of rapidly progressive spermatozoa and, consequently, underestimated the percentages of slowly progressive and non-progressive spermatozoa, compared to the conventional method. To investigate whether results drifted according to time of semen analysis, results were pooled into quarters according to date of semen analysis. CRISmAS motility results appeared more stable over time compared to the conventional analysis; however, neither method showed any trends. Apparently, CRISmAS CASA results and results from the conventional method were not comparable with respect to sperm concentration and motility analysis. This needs to be accounted for in clinics using this software and in studies of determinants of these semen characteristics.

关键词： computer-assisted semen analysis reproduction semen analysis sperm concentration sperm motility

diet composition of the lizard P odarcis lilfordi (Lacertidae) on 2 small islands: an individualresource network approach

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Current Zoology 2020年第1期66卷 39-49页

作者： Silvia SANTAmARIA Camilla Aviaaja ENOKSEN jens m.OLESEN Giacomo TAVECCHIA Andreu ROTGER Jose manuel IGUAL Anna TRAVESET Global Change Research Group Inst.Mediterrani d'Estudis Avanqats(CSIC-UIB)C/Miquel Marques 21E07190 EsporlesMallorcaBalearic IslandsSpain Section for Ecoinformatics&Biodiversity Department of BioscienceAarhus UniversityAarhus C8000Denmark Animal Ecology and demography Group Inst.Mediterrani d'Estudis Avanqats(CSIC-UIB)C/Miquel Marques 21EsporlesMallorcaBalearic IslandsE07190Spain

despite it is widely accepted that intrapopulation variation is fundamental to ecological and evolutionary processes,this level of information has only recently been included into network analysis of species/population *** done,it has revealed non-random patterns in the distribution of trophic *** in resource use among individuals is the most recurrent observed pattern,often accompanied by an absence of modularity,but no previous studies examine bipartite *** use network analysis to describe the diet composition of the Balearic endemic lizard Podarcis lilfordi in 2 islets at population and individual levels,based on the occurrence of food items in fecal *** objectives are to 1)compare niche structure at both levels,2)characterize niche partition using nestedness and modularity,and 3)assess how size,sex,season,and spatial location influence niche *** population-level niche width was wide,but narrow at the level of the *** islet networks were nested,indicating similar ranking of the food preferences among individuals,but also modular,which was partially explained by *** and body size did not notably affect diet *** niche overlap and therefore possibly relaxed competition were observed among females in one of the islets and during spring on both ***,higher modularity in autumn suggests that higher competition could lead to specialization in both populations,because resources are usually scarce in this *** absence of spatial location influence on niche might respond to fine-grained spatio-temporally distribution of food *** traits,not included in this study,could also influence resource partitioning.

关键词： Balearic Islands individual diet composition individual-level network modularity nestedness population niche width

Small size does not restrain frugivory and seed dispersal across the evolutionary radiation of Galapagos lava lizards

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Current Zoology 2019年第4期65卷 353-361页

作者： Sandra HERVIAS-PAREJO Ruben HELENO Beatriz RUmEU Beatriz GUZmAN Pablo VARGAS jens m. OLESEN Anna TRAVESET Carlos VERA Edgar BENAVIdES manuel NOGALES Institut mediterrani d'Estudis Avanqats (CSIC-UIB) Global Change Research Group Mallorca Balearic Islands Spain Centre for Functional Ecology Department of Life Sciences University of Coimbra Portugal Real Jardin Botanico (CSIC-RJB) Madrid Spain department of Bioscience Aarhus University Denmark Galapagos National Park Puerto Ayora Santa Cruz Galapagos Ecuador department of Ecology and Evolutionary Biology Yale University USA lnstituto de Productos Naturales Agrobiologia (CSIC-IPNA) Island Ecology and Evolution Research Group Canary Islands Spain

Frugivory in lizards is often assumed to be constrained by body size;only large individuals are considered capable of consuming fruits, with the potential of acting as seed dispersers. However, only one previous study has tested the correlation of frugivory with body and head size at an archipelago scale across closely related species. All nine lava lizards (microlophus spp.) were studied on the eleven largest Galapagos islands from 2010 to 2016 to investigate whether frugivory is related to body and head size. We also tested whether fruit abunda nee in flue nces fruit con sumption and explored the effect of seed ingestion on seedling emergence time and percentage. Our results showed that across islands, lava lizards varied considerably in size (64-102 mm in mean snoutvent length) and level of frugivory (1-23%, i.e., percentage of droppings with seeds). However, level of frugivory was only weakly affected by size as fruit consumption was also common among small lizards. Lava lizards consumed fruits throughout the year and factors other than fruit abundance may be more importa nt drivers of fruit selecti on (e.g., fruit size, energy con tent of pulp). From 2,530 droppings, 1,714 seeds of at least 61 plant species were identified, 76% of the species being native to the Galapagos. most seeds (91%) showed no external structural damage. Seedling emergence time (44 versus 118 days) and percentage (20% versus 12%) were enhanced for lizardingested seeds compared to control (uningested) fruits. de-pulping by lizards (i.e., removal of pulp with potential germi nation inhibitors) might in crease the chances that at least some seeds find suitable recruitment conditi ons. We con eluded that lizards are importa nt seed dispersers throughout the year and across the whole archipelago, regardless of body size.

关键词： microlophus oceanic islands plant-animal interactions seed disperser size seed dispersal effectiveness seedling emergence

A New Species of Japalura(Squamata, Agamidae) from the Nu River Valley in Southern Hengduan mountains, Yunnan, China

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Asian Herpetological Research 2017年第2期18卷 86-95页

作者： dingqi RAO jens V.VINdUm Xiaohui mA mingxia FU Jeffery A.WILKINSON Kunming Institute of Zoology Chinese Academy of Sciences department of Herpetology California Academy of Sciences

A population of Japalura from Yunnan Province, China, previously assigned to Japalura splendida, is described as a new species. The new species has been recorded between 1 138–2 500 m in the Nu River drainage between the towns of Liuku and Binzhongluo, and on the lower western slopes of the Nushan and eastern slopes of the Goaligongshan. The new species can be distinguished from other species of Japalura, except J. dymondi, by the following combination of characters： exposed tympani, prominent dorso-lateral stripes, and small gular scales. It is very similar with but differs from J. dymondi by having smooth or feebly keeled dorsal head scales, three relatively enlarged spines on either side of the post-occiput area, strongly keeled and mucronate scales on occiput area and within the lateral stripes, back of arm and leg green, higher number of dorsal-ridge scales（dS） and fourth toe subdigital scales（T4S）. A principal component analysis of body measurements of adult male specimens of the new species and J. dymondi showed principal component 1 loading highest for upper arm length, fourth toe length and snout to eye length and principal component 2 loading highest for head width, head length and fourth toe length.

关键词： Agamidae Japalura sp.nov. Goaligongshan mountain Nujiang River Valley Hengduan mountains Yunnan China