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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

Development of high damage threshold laser-machined apodizers and gain filters for laser applications

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High Power laser Science and Engineering 2016年第3期4卷 113-119页

作者： Patrick Rambo jens Schwarz Mark Kimmel John l.Porter Sandia National laboratories

We have developed high damage threshold filters to modify the spatial profile of a high energy laser beam. The filters are formed by laser ablation of a transmissive window. The ablation sites constitute scattering centers which can be filtered in a subsequent spatial filter. By creating the filters in dielectric materials, we see an increased laser-induced damage threshold from previous filters created using ‘metal on glass' lithography.

关键词： apodization laser beam shaping laser micro-machining spatial filtering

Drought-responsive genes expressed predominantly in root tissues are enriched with homotypic cis-regulatory clusters in promoters of major cereal crops

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The Crop Journal 2017年第3期5卷 195-206页

作者： Muhammad Ramzan Khan Imran Khan Zahra Ibrar jens léon Ali Ahmed Naz Institute of Crop Science and Resource Conservation(INRES) Department of Crop Genetics and BiotechnologyRheinische Friedrich-Wilhelms University of BonnGermany National Centre for Bioinformatics(NCB) Quaid-i-Azam UniversityIslamabadPakistan National Institute for Genomics and Advanced Biotechnology(NIGAB) National Agricultural Research CentrePark RoadIslamabadPakistan

The root appears to be the most relevant organ for breeding drought stress ***, our knowledge about temporal and spatial regulation of drought-associated genes in the root remains fragmented, especially in crop plants. We performed a meta-analysis of expression divergence of essential drought-inducible genes and analyzed their association with cis-elements in model crops and major cereal crops. Our analysis of42 selected drought-inducible genes revealed that these are expressed primarily in roots,followed by shoot, leaf, and inflorescence tissues, especially in wheat. Quantitative real-time RT-PCR analysis confirmed higher expression of TaDREB2 and TaAQP7 in roots,correlated with extensive rooting and drought-stress tolerance in wheat. A promoter scan up to 2 kb upstream of the translation start site using phylogenetic footprinting revealed708 transcription factor binding sites, including drought response elements(DREs), auxin response elements(Aux REs), MYCREs/MYBREs, ABAREs, and ERD1 in 19 selected ***, these elements were organized into clusters of overlapping transcription factor binding sites known as homotypic clusters(HCTs), which modulate drought physiology in plants. Taken together, these results revealed the expression preeminence of major drought-inducible genes in the root, suggesting its crucial role in drought adaptation. The occurrence of HCTs in drought-inducible genes highlights the putative evolutionary modifications of crop plants in developing drought adaptation. We propose that these DNA motifs can be used as molecular markers for breeding drought-resilient cultivars, particularly in the cereal crops.

关键词： Gene expression Promoter DREB cis-regulatory elements Phylogeny Drought adaptation

Pressure drop of structured packing in pilot column and comparison to common correlations

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Chinese Journal of Chemical Engineering 2023年第12期64卷 281-291页

作者： Emil Madsen Randi Neerup Arne Gladis jens K.Jørsboe Nicolas von Solms Philip l.Fosbøl Center for Energy Resources Engineering(CERE) Department of Chemical and Biochemical EngineeringTechnical University of Denmark(DTU)Søltofts Plads 2292800 Kgs.LyngbyDenmark

Packed columns are widely used in the chemical industry such as absorption,stripping,distillation,and extraction in the production of *** chemicals,and *** loss and pressure drop correlations are of special interest when it comes to the hydrodynamic properties of a *** pressure loss across the column is of interest in the design phase when the size of the blower to drive the gas stream through the column has to be *** loading point and flooding point are also influenced by the pressure loss and the area of operation is determined from these *** work examines four different correlations on pressure *** correlations are(i)Ergun’s equation(1952),(ii)an improved version of Ergun’s equation by Stichlmair,Bravo,and Fair(1989),(iii)an equation developed by Billet and Schultes(1999),and(iv)an equation by Rocha,Bravo,and Fair(1993).The complexity of the correlations is increasing in the mentioned order,Ergun’s equation being the simplest *** study investigates if the more complicated correlations give better predictions to pressure drop in packed *** is determined by comparing the correlations to experimental data for pressure drop in a packed column with 8.2 m of structured packing using water as the liquid and atmospheric air as the *** experiments were carried out for determining the pressure drop in the column with liquid flows varying from 0 to 500 kg·h^(-1).At constant liquid flow,the gas flow was varied from approximately 10 to 70 kg·h^(-1).The pressure drop across the non-wetted column was best described by the correlation by Rocha et *** the pressure drop for liquid flows from 100 to 500 kg·h^(-1)was,in general,best described by Stichlmair’s *** an irrigated column,the highest deviation was a predicted pressure drop 69.6%lower than *** best prediction was 0.1%higher than the *** study shows,surprisingly,that for a system of water and atmospheric air,complica

关键词： Pressure drop correlations Packed columns Structured packing Fluid dynamics

Gene-environment interaction and male reproductive function

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Asian Journal of Andrology 2010年第3期12卷 298-307,I0007页

作者： Jonatan Axelsson jens Peter Bonde Yvonne l. Giwercman lars Rylander Aleksander Giwercman Reproductive Medicine Centre Skane University Hospital Malmo 20502 Sweden Division of Occupational and Environmental Medicine Lund University Lund 22185 Sweden Department of Occupational Medicine Copenhagen University Bispebjerg Hospital Copenhagen NV2400 Denmark Department of Clinical Sctences Malmo Lund University Malmo 20502 Sweden

As genetic factors can hardly explain the changes taking place during short time spans, environmental and lifestyle-related factors have been suggested as the causes of time-related deterioration of male reproductive function. However, considering the strong heterogeneity of male fecundity between and within populations, genetic variants might be important determinants of the individual susceptibility to the adverse effects of environment or lifestyle. Although the possible mechanisms of such interplay in relation to the reproductive system are largely unknown, some recent studies have indicated that specific genotypes may confer a larger risk of male reproductive disorders following certain exposures. This paper presents a critical review of animal and human evidence on how genes may modify environmental effects on male reproductive function. Some examples have been found that support this mechanism, but the number of studies is still limited. This type of interaction studies may improve our understanding of normal physiology and help us to identify the risk factors to male reproductive malfunction. We also shortly discuss other aspects of gene-environment interaction specifically associated with the issue of reproduction, namely environmental and lifestyle factors as the cause of sperm DNA damage. It remains to be investigated to what extent such genetic changes, by natural conception or through the use of assisted reproductive techniques, are transmitted to the next generation, thereby causing increased morbidity in the offspring.

关键词： endocrine disruption gene-environment interaction persistent organic pollutants semen quality testicular cancer

Patients with inflammatory bowel disease have increased risk of autoimmune and inflammatory diseases

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World Journal of Gastroenterology 2017年第33期23卷 6137-6146页

作者： Morten l Halling jens Kjeldsen Torben Knudsen Jan Nielsen lars Koch Hansen Department of Gast-roenterology and Hepatology Hospital of Southwest Jutland Department of Medical Gastroenterology S Odense University Hospital Center for Clinical Epidemiology Odense Uni-versity Hospital

AIM To investigate whether immune mediated diseases(IMD) are more frequent in patients with inflammatory bowel disease(IBD).METHODS In this population based registry study,a total of 47325 patients with IBD were alive and registered in the Danish National Patient Registry on December 16,2013. Controls were randomly selected from the Danish Civil Registration System(CRS) and matched for sex,age,and municipality. We used ICD 10 codes to identify the diagnoses of the included patients. The IBD population was divided into three subgroups: Ulcerative colitis(UC),Crohn's disease(CD) and Both the latter referring to those registered with both diagnoses. Subsequently,odds-ratios(OR) and 95%CI were obtained separately for each group and their respective controls. The use of Bonferoni post-test correction adjusted the significance level to P lues were estimated using Fisher's exact *** There were significantly more women than men in the registry,and a greater percentage of comorbidity in the IBD groups(P ll significantly more frequent in the IBD group. Sixteen were associated with UC versus twelve with CD. In both UC and CD ORs were significantly increased(P lerosing cholangitis(PSC),celiac disease,type 1 diabetes(T1D),sarcoidosis,asthma,iridocyclitis,psoriasis,pyoderma gangrenosum,rheumatoid arthritis,and ankylosing spondylitis. Restricted to UC(P liary cholangitis,Grave's disease,polymyalgia rheumatica,temporal arteritis,and atrophic gastritis. Restricted to CD(P leritis. Restricted to women with UC(P l arteritis,and polymyalgia rheumatica. Restricted to women with CD were episcleritis,rheumatoid arthritis,and psoriatic arthritis. The only disease restricted to men(P lUSION Immune mediated diseases were si

关键词： Immune mediated diseases Ulcerative colitis Risk Prevalence Registry Chronic inflammatory diseases Autoimmune diseases Inflammatory bowel disease Crohn’s disease extraintestinal manifestations

Day length constrains the time budget of aphid predators

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Insect Science 2019年第1期26卷 164-170页

作者： jens Joschinski Tim Kiess Jochen Krauss Department of Animal Ecology and Tropical Biology BiocentreUniversity of WEirzburgWEtrzburgGermany

Phenology shifts and range expansions cause organisms to experience novel day length-temperature *** on the temporal niche,organisms may benefit or suffer from changes in day length,thus potentially affecting phenological adaptation. We assessed the impact of day length changes on larvae of Chrysoperla carnea (Stephens) and Episyrphus balteatus (De Geer),both of which prey on *** *** are night-active,whereas those of *** appear to be *** subjected both species in climate chambers to day lengths of 16 :8 l :D and,to circumvent diapause responses,20 :4 l :*** recorded development times and predation rates of both species. *** grew 13%faster in the 16 :8 l :D treatment and preyed on significantly more *** contrast,*** grew 13% faster in the 20 :4 l :D treatment and higher predation rates in 20 :4 l :D were marginally *** results show that day length affects development and predation,but that the direction depends on species. Such differences in the use of day length may alter the efficiency ofbiocontrol agents in a changing climate.

关键词： Chiysoperla carnea climate change Episyrphus balteatus insect timing phenology photoperiod

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

TRAUMATIC DENTAl INJURIES - A MANUAl 3E 3

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