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Multiple endocrine factors regulate nutrient mobilization and storage in Aedes aegypti during a gonadotrophic cycle

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Insect Science 2023年第2期30卷 425-442页

作者： Xiaoyi Dou Kangkang Chen Mark R.Brown Michael R.strand Department of Entomology University of GeorgiaAthensGeorgia30602United States Department of Plant Protection College of Horticulture and Plant ProtectionYangzhou UniversityYangzhouJiangsu ProvinceChina

Anautogenous mosquitoes must blood feed on a vertebrate host to produce eggs.Each gonadotrophic cycle is subdivided into a sugar-feeding previtellogenic phase that produces primary follicles and a blood meal-activated vitellogenic phase in which large numbers of eggs synchronously mature and are laid.Multiple endocrine factors including juvenile hormone(JH),insulin-like peptides(ILPs),ovary ecdysteroidogenic hormone(OEH),and 20-hydroxyecdysone(20E)coordinate each gonadotrophic cycle.Egg formation also requires nutrients from feeding that are stored in the fat body.Regulation of egg formation is best understood in Aedes aegypti but the role different endocrine factors play in regulating nutrient mobilization and storage remains unclear.In this study,we report that adult female Ae.aegypti maintained triacylglycerol(TAG)stores during the previtellogenic phase of the first gonadotrophic cycle while glycogen stores declined.In contrast,TAG and glycogen stores were rapidly mobilized during the vitellogenic phase and then replenishment.Several genes encoding enzymes with functions in TAG and glycogen metabolism were differentially expressed in the fat body,which suggested regulation was mediated in part at the transcriptional level.Gain of function assays indicated that stored nutrients were primarily mobilized by adipokinetic hormone(AKH)while juvenoids and OEH regulated replenishment.ILP3 further showed evidence of negatively regulating certain lipolytic enzymes.Loss of function assays indicated AKH depends on the AKH receptor(AKHR)for function.Altogether,our results indicate that the opposing activities of different hormones regulate nutrient stores during a gonadotrophic cycle in Ae.aegypti.

关键词： adipokinetic hormone ecdysone endocrine glycogen insulin-like peptide juvenile hormone mosquito nutrient ovary ecdysteroidogenic hormone triacylglycerol

Evolution of interventional endoscopic ultrasound

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Gastroenterology Report 2023年第1期11卷 131-139页

作者： Mark J.Radlinski Daniel S.strand Vanessa M.Shami Division of Gastroenterology and Hepatology University of VirginiaCharlottesvilleVAUSA

Endoscopic ultrasound(EUS)has become an indispensable modality for the assessment of the gastrointestinal tract and adjacent structures since its origin in the 1980s.Following the development of the linear echoendoscope,EUS has evolved from a purely diagnostic modality to a sophisticated tool for intervention,with numerous luminal,pancreaticobiliary,and hepatic applications.Broadly,these applications may be subdivided into three categories:transluminal drainage or access procedures,injection therapy,and EUS-guided liver interventions.Transluminal drainage or access procedures include management of pancreatic fluid collection,EUS-guided biliary drainage,EUS-guided bile duct drainage,EUS-guided pancreatic duct drainage,and enteral anastomosis formation.Injection therapies include therapeutic EUS-guided injections for management of malignancies accessible by EUS.EUS-guided liver applications include EUS-guided liver biopsy,EUS-guided portal pressure gradient measurement,and EUS-guided vascular therapies.In this review,we discuss the origins of each of these EUS applications,evolution of techniques leading to the current status,and future directions of EUS-guided interventional therapy.

关键词： endoscopic ultrasound interventional endoscopic ultrasound biliary drainage gastrojejunostomy pancreatic pseudocyst drainage

Genomic selection in plant breeding:Key factors shaping two decades of progress

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Molecular Plant 2024年第4期17卷 552-578页

作者： Admas Alemu Johanna Astrand Osval A.Montesinos-López Julio Isidro y Sanchez Javier Fernandez-Gónzalez Wuletaw Tadesse Ramesh R.Vetukuri Anders S.Carlsson Alf Ceplitis JoséCrossa Rodomiro Ortiz Aakash Chawade Department of Plant Breeding Swedish University of Agricultural SciencesAlnarpSweden Lantmannen Lantbruk SvalövSweden Facultad de Telematica University de ColimaColimaColima 28040Mexico Centro de Biotecnología y Genómica de Plantas(CBGP UPM-INIA)Universidad Politécnica de Madrid(UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria(INIA)Campus de Montegancedo-UPM28223 MadridSpain International Center for Agricultural Research in the Dry Areas(ICARDA) RabatMorocco International Maize and Wheat Improvement Center(CIMMYT) Km 45Carretera México-VeracruzTexcocoMéxico 52640Mexico

Genomic selection,the application of genomic prediction(GP)models to select candidate individuals,has significantly advanced in the past two decades,effectively accelerating genetic gains in plant breeding.This article provides a holistic overview of key factors that have influenced GP in plant breeding during this period.We delved into the pivotal roles of training population size and genetic diversity,and their relationship with the breeding population,in determining GP accuracy.Special emphasis was placed on optimizing training population size.We explored its benefits and the associated diminishing returns beyond an optimum size.This was done while considering the balance between resource allocation and maximizing prediction accuracy through current optimization algorithms.The density and distribution of single-nucleotide polymorphisms,level of linkage disequilibrium,genetic complexity,trait heritability,statistical machine-learning methods,and non-additive effects are the other vital factors.Using wheat,maize,and potato as examples,we summarize the effect of these factors on the accuracy of GP for various traits.The search for high accuracy in GP—theoretically reaching one when using the Pearson’s correlation as a metric—is an active research area as yet far from optimal for various traits.We hypothesize that with ultra-high sizes of genotypic and phenotypic datasets,effective training population optimization methods and support from other omics approaches(transcriptomics,metabolomics and proteomics)coupled with deep-learning algorithms could overcome the boundaries of current limitations to achieve the highest possible prediction accuracy,making genomic selection an effective tool in plant breeding.

关键词： genomic selection genetic gain genomic prediction optimization deep learning training population optimization

The insect cellular immune response

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Insect Science 2008年第1期15卷 1-14页

作者： Michael R. strand Department of Entomology and Center for Emerging and Tropical Global Diseases University of Georgia Athens Georgia USA

The innate immune system of insects is divided into humoral defenses that include the production of soluble effector molecules and cellular defenses like phagocytosis and encapsulation that are mediated by hemocytes. This review summarizes current understand- ing of the cellular immune response. Insects produce several terminally differentiated types of hemocytes that are distinguished by morphology, molecular and antigenic markers, and function. The differentiated hemocytes that circulate in larval or nymphal stage insects arise from two sources： progenitor cells produced during embryogenesis and mesodermally derived hematopoietic organs. Regulation of hematopoiesis and hemocyte differentiation also involves several different signaling pathways. Phagocytosis and encapsulation require that hemocytes first recognize a given target as foreign followed by activation of downstream signaling and effector responses. A number of humoral and cellular receptors have been identified that recognize different microbes and multicellular parasites. In turn, activation of these receptors stimulates a number of signaling pathways that regulate different hemocyte functions. Recent studies also identify hemocytes as important sources Of a number of humoral effector molecules required for killing different foreign invaders.

关键词： antimicrobial peptides clotting cytokines Diptera Drosophila encapsulation,hemocytes immunity insects Lepidoptera nodulation phagocytosis

Interplay between HEAT SHOCK PROTEIN 90 and HY5 Controls PhANG Expression in Response to the GUN5 Plastid Signal

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Molecular Plant 2012年第4期5卷 901-913页

作者： Peter Kindgren Louise Noren Juan de Dios Barajas Lopez Jehad Shaikhali Asa strand Umea Plant Science Centre Department of Plant Physiology Umea University S-901 87 Umea Sweden

The presence of genes encoding organellar proteins in different cellular compartments necessitates a tight coordination of expression by the different genomes of the eukaryotic cell. This coordination of gene expression is achieved by organelle-to-nucleus or retrograde communication. Stress-induced perturbations of the tetrapyrrole pathway trigger large changes in nuclear gene expression in plants. Recently, we identified HSP90 proteins as ligands of the pu- tative plastid signal Mg-ProtolX. In order to investigate whether the interaction between HSP90 and Mg-ProtolX is bio- logically relevant, we produced transgenic lines with reduced levels of cytosolic HSP90 in wild-type and gun5 backgrounds. Our work reveals that HSP90 proteins respond to the tetrapyrrole-mediated plastid signal to control expres- sion of photosynthesis-associated nuclear genes （PhANG） during the response to oxidative stress. We also show that the hy5 mutant is insensitive to tetrapyrrole accumulation and that Mg-ProtolX, cytosolic HSP90, and HY5 are all part of the same signaling pathway. These findings suggest that a regulatory complex controlling gene expression that includes HSP90 proteins and a transcription factor that is modified by tetrapyrroles in response to changes in the environment is evolutionarily conserved between yeast and plants.

关键词： abiotic/environmental stress cell signaling organelle biogenesis/function.

Impacts of Norwegian large carnivore management strategy on national grazing sector

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Journal of Mountain Science 2019年第11期16卷 2470-2483页

作者： Inger HANSEN Geir-Harald strand Auvikki de BOON Camilla SANDSTROM Norwegian Institute of Bioeconomy Research Box 115N-1431 AsNorway Department of Political Science Umea University90187 UmeaSweden

Increasing populations of large carnivores are leading to tension and conflicts with livestock production,a situation that potentially might escalate.In Norway the objective of the large carnivore policy is two-folded:to ensure viable carnivore populations and to secure a sustainable grazing industry.The main instrument is zonation,with carnivore management zones(CMZs)prioritized for reproduction of the large carnivore species separated from other areas prioritized for grazing livestock.The objective of this paper is to describe current knowledge about the impact of the zoning management strategy on the grazing industry.This is done by documenting status and changes in sheep production,losses of livestock to predating carnivores,and the use of grazing areas inside and outside the CMZs.CMZsoffering protection for lynx,wolverine,bear and wolf cover 55%of the Norwegian mainland.30%of the sheep and 50%of the Sami reindeer grazing areas are found inside the CMZs.Livestock(semi-domestic reindeer excluded)is using 59%of the available natural pasture areas outside the CMZs,but only 26%inside the CMZs.The lowest use of available grazing areas was found inside zones for wolves(12%)and brown bears(6%).Livestock in these zones are confined to fenced enclosures,mostly on the farm itself,or moved to pastures outside the management zone for summer grazing.Livestock losses increased in the affected regions during the period when carnivores were reestablished.Later,losses declined when CMZs were established and mitigation efforts were implemented in these zones.The bulk of sheep and reindeer killed by carnivores are now found in boundary areas within 50 km off the CMZs,where sheep are still grazing on open mountain and forest ranges.Therefore,instruments to protect livestock in areas close to the CMZs are also needed.The number of sheep declined inside the CMZs from 1999 to 2014,but increased outside the zones.The reduction in the absolute number of sheep in the CMZs is balanced by a similar increase outside,thus the total sheep

关键词： Carnivore management Depredation Management zones Rangeland Sheep Large carnivore policy

Advances in prostate cancer research models:From transgenic mice to tumor xenografting models

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Asian Journal of Urology 2016年第2期3卷 64-74页

作者： Yuejiao Huang Chun Cheng Chong Zhang Yonghui Zhang Miaomiao Chen Douglas W.strand Ming Jiang Department of Oncology Affiliated Cancer Hospital of Nantong UniversityNantongJiangsuChina Department of Immunology Nantong University School of MedicineNantongJiangsuChina Laboratory of Nuclear Receptors and Cancer Research Center for Basic Medical ResearchNantong University School of MedicineNantongJiangsuChina Department of Urology UT Southernwestern Medical CenterDallasTXUSA Institute of Medicine and Public Health Division of EpidemiologyDepartment of MedicineVanderbilt-Ingram Cancer CenterVanderbilt University Medical CenterNashvilleTNUSA

The identification of the origin and molecular characteristics of prostate cancer(PCa)has crucial implications for personalized treatment.The development of effective treatments for PCa has been limited;however,the recent establishment of several transgenicmouse lines and/or xenografting models is better reflecting the disease in vivo.With appropriate models,valuable tools for elucidating the functions of specific genes have gone deep into prostate development and carcinogenesis.In the present review,we summarize a number of important PCa research models established in our laboratories(PSA-Cre-ERT2/PTEN transgenic mouse models,AP-OX model,tissue recombination-xenografting models and PDX models),which represent advances of translational models from transgenic mouse lines to human tumor xenografting.Better understanding of the developments of these models will offer new insights into tumor progression and may help explain the functional significance of genetic variations in PCa.Additionally,this understanding could lead to new modes for curing PCa based on their particular biological phenotypes.

关键词： Prostate cancer Transgenic mouse lines Tumor xenografting models Translational medical systems

Transcript profiling of a novel plant meristem,the monocot cambium

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Journal of Integrative Plant Biology 2017年第6期59卷 436-449页

作者： matthew Zinkgraf Suzanne Gerttula Andrew Groover US Forest Service Pacific Southwest Research StationDavisCaliforniaUSA Department of Computer Science University of CaliforniaDavisUSA Department of Plant Biology University of CaliforniaDavisUSA

While monocots lack the ability to produce a vascular cambium or woody growth, some monocot lineages evolved a novel lateral meristem, the monocot cambium, which supports secondary radial growth of stems. In contrast to the vascular cambium found in woody angiosperm and gymnosperm species, the monocot cambium produces secondary vascular bundles, which have an amphivasal organization of tracheids encircling a central strand of phloem. Currently there is no information concerning the molecular genetic basis of the develop- ment or evolution of the monocot cambium. Here we report high-quality transcriptomes for monocot cambium and early derivative tissues in two monocot genera, Yucca and Cordyline. Monocot cambium transcript profiles were compared to those of vascular cambia and secondary xylem tissues of two forest tree species, Populus trichocarpa and Eucalyptus grandis. Monocot cambium transcript levels showed that there are extensive overlaps between the regulation of monocot cambia and vascular cambia. Candidate regulatory genes that vary between the monocot and vascular cambia were also identified, and included members of the KANADI and CLE families involved in polarity and cell-cell signaling, respectively. We suggest that the monocot cambium may have evolved in part through reactivation of genetic mechanisms involved in vascular cambium regulation.

关键词： Chun-Ming Liu, Institute of Crop Science, CAAS, ChinaReceived Feb. 18, 2017 Accepted Mar. 15, 2017 Online on Mar. 17,2017

Ischemia/reperfusion injury in porcine intestine-Viability assessment

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World Journal of Gastroenterology 2018年第18期24卷 2009-2023页

作者： Runar J strand-Amundsen Henrik M Reims Finn P Reinholt Tom E Ruud Runkuan Yang Jan O Hogetveit Tor I Tonnessen Department of Clinical and Biomedical Engineering Oslo University HospitalOslo 0424Norway Department of Physics University of OsloOslo 0316Norway Department of Pathology Oslo University HospitalOslo 0424Norway Institute for Surgical Research Oslo University HospitalOslo 0424Norway Department of Surgery Baerum HospitalVestre Viken Hospital TrustDrammen 3004Norway Department of Emergencies and Critical Care Oslo University HospitalOslo 0424Norway Institute of Clinical Medicine University of OsloOslo 0424Norway

AIM To investigate viability assessment of segmental small bowel ischemia/reperfusion in a porcine model.METHODS In 15 pigs, five or six 30-cm segments of jejunum were simultaneously made ischemic by clamping the mesenteric arteries and veins for 1 to 16 h. Reperfusion was initiated after different intervals of ischemia(1-8 h) and subsequently monitored for 5-15 h. The intestinal segments were regularly photographed and assessed visually and by palpation. Intraluminal lactate and glycerol concentrations were measured by microdialysis, and samples were collected for light microscopy and transmission electron microscopy. The histological changes were described and graded.RESULTS Using light microscopy, the jejunum was considered as viable until 6 h of ischemia, while with transmission electron microscopy the ischemic muscularis propria was considered viable until 5 h of ischemia. However, following ≥ 1 h of reperfusion, only segments that had been ischemic for ≤ 3 h appeared viable, suggesting a possible upper limit for viability in the porcine mesenteric occlusion model. Although intraluminal microdialysis allowed us to closely monitor the onset and duration of ischemia and the onset of reperfusion, we were unable to find sufficient level of association between tissue viability and metabolic markers to conclude that microdialysis is clinically relevant for viability assessment. Evaluation of color and motility appears to be poor indicators of intestinal viability.CONCLUSION Three hours of total ischemia of the small bowel followed by reperfusion appears to be the upper limit for viability in this porcine mesenteric ischemia model.

关键词： Viability histology reperfusion ischemia microdialysis jejunum porcine model