检索结果-南通市图书馆

Culture conditions for equine bone marrow mesenchymal stem cells and expression of key transcription factors during their differentiation into osteoblasts

在线全文

学校读者我要写书评

暂无评论

Journal of Animal Science and Biotechnology 2014年第2期5卷 163-172页

作者： elizabeth R A Glynn Alfredo Sanchez Londono Steven A Zinn Thomas A Hoagl Kristen e Govoni Department of Animal Science University of Connecticut3636 Horsebarn Road Ext.Unit 4040StorrsCT 06269-4040USA Department of environmental and Population Health Tufts University North GraftonMA 01536USA

Background： The use of equine bone marrow mesenchymal stem cells （BMSC） is a novel method to improve fracture healing in horses. However, additional research is needed to identify optimal culture conditions and to determine the mechanisms involved in regulating BMSC differentiation into osteoblasts. The objectives of the experiments were to determine： 1） if autologous or commercial serum is better for proliferation and differentiation of equine BMSC into osteoblasts, and 2） the expression of key transcription factors during the differentiation of equine BMSC into osteoblasts. equine BMSC were isolated from the sterna of 3 horses, treated with purchased fetal bovine serum （FBS） or autologous horse serum （HS）, and cell proliferation determined. To induce osteoblast differentiation, cells were incubated with L-ascorbic acid-2-phosphate and glycerol-2-phosphate in the presence or absence of human bone morphogenetic protein2 （BMP2）, dexamethasone （DeX）, or combination of the two. Alkaline phosphatase （ALP） activity, a marker of osteoblast differentiation, was determined by eLISA. Total RNA was isolated from differentiating BMSC between d 0 to 18 to determine expression of runt-reloted tronscrJption foctor2 （Runx2）, osterix （Osx）, and T-box3 （Tbx3）. Data were analyzed by ANOVA. Results： Relative to control, FBS and HS increased cell number （133 ± 5 and 116 ± 5%, respectively; P 〈 0.001） and 5-bromo- 2＇-deoxyuridine （BrdU） incorporation （167 ± 6 and 120 ± 6%, respectively; P 〈 0.001）. Treatment with DeX increased ALP activity compared with control （1,638 ± 38%; P 〈 0.001）. In the absence and presence of Dex, BMP-2 did not alter ALP activity （P 〉 0.8）. Runt-reloted transcription foctor2 expression increased 3-fold （P 〈 0.001） by d 6 of culture. Osterix expression increased 94old （P 〈 0.05） by d 18 of culture. expression of Tbx3 increased 1.8-fold at d 3 （P 〈 0.01）; however expression was reduced 4-fold at d 18 （P 〈 0.01）. Conclusions： Dexamethasone, but not BMP-2, is requir

关键词： Bone marrow mesenchymal stem cells Cell culture equine Osteoblasts Transcription factors

Associations between aerobic and muscle-strengthening physical activity,sleep duration,and risk of all-cause mortality:A prospective cohort study of 282,473 ***

在线全文

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2023年第1期12卷 65-72页

作者： Mitch J.Duncan Stina Oftedal Christopher e Kline Ronald C.Plotnikoff elizabeth G.Holliday School of Medicine&Public Health College of HealthMedicineand WellbeingThe University of NewcastleCallaghanNSW 2308Australia Priority Research Centre for Physical Activity and Nutrition The University of NewcastleCallaghanNSW 2308Australia Department of Health&Human Development The University of PittsburghPittsburghPA 15261USA School of education University of NewcastleCallaghanNSW 2308Australia

Purpose:To examine the joint associations between meeting guidelines for physical activity(PA)and sleep duration and all-cause mortality risk among ***:Participants were adults(n=282,473)aged 18-84 years who participated in the 2004-2014 *** Health Interview *** status was ascertained using the National Death Index through December ***-reported PA(Active:meeting both aerobic(AeR)and muscle-strengthening(MSA)guidelines,AeR only(AeR),MSA only(MSA),or not meeting either AeR or MSA(Inactive))and sleep duration(Short,recommended(Rec),or Long)were classified according to guidelines,and 12 PA-sleep categories were *** hazard ratios and 95%confidence intervals(95%CIs)for all-cause mortality risk were estimated using Cox proportional hazards regression ***:A total of 282,473 participants(55%females)were included;18,793 deaths(6.7%)occurred over an average follow-up of 5.4 *** to the Active-Rec group,all other PA-sleep groups were associated with increased mortality risk except for the Active-Short group(hazard ratio=1.08;95%CI:0.92-1.26).The combination of long sleep with either MSA or Inactive appeared to be *** a given sleep duration,mortality risk progressively increased among participants classified as AeR,MSA,and *** each activity level,the mortality risk was greatest among adults with long ***:Relative to adults meeting guidelines for both PA and sleep duration,adults who failed to meet guidelines for both AeR and muscle strengthening PA and who also failed to meet sleep duration guidelines had elevated all-cause mortality *** results support interventions targeting both PA and sleep duration to reduce mortality risk.

关键词： Activity-sleep patterns All-cause mortality Prospective Resistance training

Histone Acetylation, VeRNALIZATION INSeNSITIVe 3, FLOWeRING LOCUS C, and the Vernalization Response

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2009年第4期2卷 724-737页

作者： Donna M. Bond elizabeth S. Dennis Barry J. Pogson e. Jean Finnegan CSIRO Plant Industry Canberra Australia ARC Centre of excellence in Plant energy Biology School of Biochemistry and Molecular Biology Australian National University Canberra Australia

The quantitative induction of VIN3 by low temperatures is required for PRC2 repression of FLC and promotion of flowering （vernalization） in Arabidopsis. Histone acetylation, a chromatin modification commonly associated with gene transcription, increased on VIN3 chromatin in two spatially and temporally distinct phases in response to low temperatures. During short-term cold exposure, histone H3 acetylation at the transcription start site rapidly increased, implying that it is required for VlN3 induction. Subsequent changes in histone H3 and H4 acetylation occurred following continued VIN3 transcription during prolonged cold exposure. Members of the SAGA-like transcriptional adaptor complex, including the histone acetyltransferase GCNS, which induces expression of the cold acclimation pathway genes, do not regulate VlN3 induction during cold exposure, indicating that the cold acclimation pathway and the cold-induction of VlN3 are regulated by different transcriptional mechanisms. Mutations in the other 11 histone acetyltransferase genes did not affect VlN3 induction. However, nicotinamide, a histone deacetyiase inhibitor, induced VIN3 and altered histone acetylation at the VIN3 locus. VIN3 induction was proportional to the length of nicotinamide treatment, which was associated with an early-flowering phenotype and repression of FLC. However, unlike vernalization, the repression of FLC was independent of VIN3 activity. Nicotinamide treatment did not cause a change in the expression of any genes in the autonomous pathway or members of the PRC2 complex, the well characterized repressors of FLC. Our data suggest that FLC is repressed via a novel pathway involving the SIR2 class of histone deacetylases.

关键词： Cold acclimation histone acetyltransferase histone deacetylase SIR2 nicotinamide.

Investigation of factors influencing roof stability at a Western *** coal mine

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2019年第1期29卷 139-143页

作者： Meriel Young Gabriel Walton elizabeth Holley Department.Geology&Geol.engineering Colorado School of Mines Department Mining engineering Colorado School of Mines

The coal mine roof rating(CMRR) was developed to bridge the gap between geological variation in underground coal mines and engineering design. The CMRR accounts for the compressive strength of the immediate roof, the shear strength and intensity of any discontinuities present, and the moisture sensitivity of the immediate roof. The CMRR has been widely used and validated in eastern US coal mines, but it has seen limited application in the Western US. This study focuses on roof behavior at a Western coal mine(Mine A). Mine A shows significant lateral geological variation, along with localized faulting and a laterally extensive sandstone channel network. The CMRR is not used to predict roof instability at the mine. It is, therefore, hypothesized that there are other factors that are correlated with roof instability in underground coal mines that could potentially also be considered in conjunction with the *** hypothesis was tested by collecting 30 CMRR measurements at Mine A. At each measurement location, a binary record of the roof condition(stable or unstable) was made, and other parameters such as depth of cover, presence of faulting, and sandstone channels were also recorded. ANOVA tests showed that the CMRR values and the roof conditions were not strongly correlated, indicating that the CMRR input criteria are not fully predictive of roof stability at this mine. The CMRR values showed statistically significant correlations(p less than 0.05) with faulting as well as with location at an intersection. For areas that had previously experienced roof fall but were currently stable, faulting was correlated with roof condition(p less than 0.05) only when the condition was classified as unstable.

关键词： Coal mine roof stability CMRR Western U.S.coal Case study

Laser capture microdissection and genetic analysis of carbon-labeled Kupffer cells

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2009年第14期15卷 1708-1718页

作者： Stephan Gehring edmond Sabo Maryann e San Martin elizabeth M Dickson Chao-Wen Cheng Stephen H Gregory Department of Medicine Rhode Island Hospital and The Warren Alpert Medical School of Brown University Providence RI 02903 United States Department of Pathology Rhode Island Hospital and The Warren Alpert Medical School of Brown University Providence RI 02903 United States zentrum fur Kinder- und Jugendmedizin der Universitaitsmedizin der Johannes Gutenberg-Universitait 55101 Mainz Germany

AIM： To develop a method of labeling and microdissecting mouse Kupffer cells within an extraordinarily short period of time using laser capture microdissection （LCM）. MeTHODS： Tissues are complex structures comprised of a heterogeneous population of interconnected cells. LCM offers a method of isolating a single cell type from specific regions of a tissue section. LCM is an essential approach used in conjunction with molecular analysis to study the functional interaction of cells in their native tissue environment. The process of labeling and acquiring cells by LCM prior to mRNA isolation can be elaborate, thereby subjecting the RNA to considerable degradation. Kupffer cell labeling is achieved by injecting India ink intravenously, thus circumventing the need for in vitro staining. The significance of this novel approach was validated using a cholestatic liver injury model. ReSULTS： mRNA extracted from the microdissected cell population displayed marked increases in colonystimulating factor-1 receptor and Kupffer cell receptor message expression, which demonstrated Kupffer cell enrichment. Gene expression by Kupffer ceils derived from bile-duct-ligated, versus sham-operated, mice was compared. Microarray analysis revealed a significant （2.5-fold, q value 〈 10） change in 493 genes. Based on this fold-change and a standardized PubMed search, 10 genes were identified that were relevant to the ability of Kupffer cells to suppress liver injury. CONCLUSION; The methodology outlined herein provides an approach to isolating high quality RNA from Kupffer cells, without altering the tissue integrity.

关键词： Kupffer cells India ink Laser capturemicrodissection Bile duct ligation DNA microarray

Accommodating the bacterial decoding release factor as an alien protein among the RNAs at the active site of the ribosome

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Cell Research 2007年第7期17卷 591-607页

作者： elizabeth S Poole David J Young Marjan e Askarian-Amiri Debbie-Jane G Scarlett Warren P Tate Department of Biochemistry University of OtagoP.O.Box 56 DunedinNew Zealand

The decoding release factor (RF) triggers termination of protein synthesis by functionally mimicking a tRNA to spanthe decoding centre and the peptidyl transferase centre (PTC) of the ribosome. Structurally, it must fit into a site craftedfor a tRNA and surrounded by five other RNAs, namely the adjacent peptidyl tRNA carrying the completed polypeptide,the mRNA and the three rRNAs. This is achieved by extending a structural domain from the body of the protein thatresults in a critical conformational change allowing it to contact the PTC. A structural model of the bacterial terminationcomplex with the accommodated RF shows that it makes close contact with the first, second and third bases of the stopcodon in the mRNA with two separate loops of structure: the anticodon loop and the loop at the tip of helix α5. Theanticodon loop also makes contact with the base following the stop codon that is known to strongly influence termina-tion efficiency. It confirms the close contact of domain 3 of the protein with the key RNA structures of the PTC. ThemRNA signal for termination includes sequences upstream as well as downstream of the stop codon, and this may reflectstructural restrictions for specific combinations of tRNA and RF to be bound onto the ribosome together. An unbiasedSeLeX approach has been investigated as a tool to identify potential rRNA-binding contacts of the bacterial RF in itsdifferent binding conformations within the active centre of the ribosome.

关键词： release factor protein synthesis termination tRNA functional mimicry molecular mimicry SeLeX ribosome

Preoperative virtual video visits only:a convenient option that should be offered to caregivers beyond the pandemic

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

World Journal of Pediatric Surgery 2022年第3期5卷 169-175页

作者： Danielle Dougherty Allison R Thompson Karen elizabeth Speck erin e Perrone Section of Pediatric Surgery Department of SurgeryUniversity of Michigan Health SystemAnn ArborMichiganUSA Department of Health Behavior and Health education University of Michigan School of Public HealthAnn ArborMIUSA

Objective During the COVID-19 pandemic,our group implemented preoperative video visits(VVs)to limit physical *** aim of this study was to determine caregivers’and providers’perceptions of this practice and to determine feasibility for *** All patients who had only a preoperative VV prior to an elective surgery were identified from March-October ***,surgeons,and clinic staff were surveyed about their *** Thirty-four preoperative VVs were followed by an elective surgery without a preceding in-person *** the 31 caregiver surveys completed,the majority strongly agreed that the VV was more convenient(87%,n=27).eighty-one percent(n=25)strongly agreed or agreed that the VV saved them ***-four percent(n=29)strongly agreed or agreed that they would choose the VV option *** saved an average travel distance of 60.3 miles one way(range 6.1-480).Of the 13/17 providers who responded,77%(n=10)expressed that the practice should *** Virtual health became a necessity during the pandemic,and caregivers were overwhelmingly *** VVs as an option beyond the pandemic may be a reasonable and effective way to help eliminate some of the hurdles that impede healthcare-seeking behavior and should be offered.

关键词： convenient beyond eliminate

Mitochondrial membrane protein Bcl-xL, a regulator of adult neuronal growth and synaptic plasticity: multiple functions beyond apoptosis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2014年第19期9卷 1706-1707页

作者： Han-A Park elizabeth A.Jonas Department of Internal Medicine Section of EndocrinologyYale University

The B-cell lymphoma 2 （Bcl2） family of proteins participates in cell death or survival through a mitochondrial pathway. The pro-apoptotic members of the Bcl2 family such as Bim, Bid, Bax and Bak trigger cell death by contributing to the enhancement of mitochondrial outer membrane permeabil- ity to pro-apoptotic factors such as cytochrome c, with the subsequent activation of caspases. The anti-apoptotic mem- bers, such as B-cell lymphoma-extra large （Bd-xL）, block the pro-apoptotic Bcl2 members and prevent cell death. Bcl-xL is abundantly expressed during development and in mature neurons, suggesting that it plays a role in protection from death from untoward events occurring in adult life such as ischemia, inflammation or trauma. When these neurotoxic in- sults occur, Bcl-xL translocates to mitochondria and prevents activation and homo-oligomerization of pro-apoptotic family members such Bax and Bak. Numerous studies have shown pro-survival roles for Bcl-xL in adult neurons using various models; nevertheless, the role of Bcl-xL outside of the field of neuronal death, i.e., in adult neuronal growth, excitability or synaptic plasticity, has not been studied in depth.

关键词： Mitochondrial membrane protein Bcl-xL a regulator of adult neuronal growth and synaptic plasticity RNAi Bax

Rapid and flexible segmentation of electron microscopy data using few-shot machine learning

在线全文

学校读者我要写书评

暂无评论

npj Computational Materials 2021年第1期7卷 1733-1741页

作者： Sarah Akers elizabeth Kautz Andrea Trevino-Gavito Matthew Olszta Bethany e.Matthews Le Wang Yingge Du Steven R.Spurgeon National Security Directorate Pacific Northwest National LaboratoryRichlandWA 99352USA energy and environment Directorate Pacific Northwest National LaboratoryRichlandWA 99352USA Department of Industrial engineering and Management Sciences Northwestern UniversityEvanstonIL 60208USA Physical and Computational Sciences Directorate Pacific Northwest National LaboratoryRichlandWA 99352USA

Automatic segmentation of key microstructural features in atomic-scale electron microscope images is critical to improved understanding of structure–property relationships in many important materials and chemical ***,the present paradigm involves time-intensive manual analysis that is inherently biased,error-prone,and unable to accommodate the large volumes of data produced by modern *** more automated approaches have been proposed,many are not robust to a high variety of data,and do not generalize well to diverse microstructural features and material ***,we present a flexible,semi-supervised few-shot machine learning approach for segmentation of scanning transmission electron microscopy images of three oxide material systems:(1)epitaxial heterostructures of SrTiO_(3)/Ge,(2)La_(0.8)Sr_(0.2)FeO_(3) thin films,and(3)MoO_(3) *** demonstrate that the few-shot learning method is more robust against noise,more reconfigurable,and requires less data than conventional image analysis *** approach can enable rapid image classification and microstructural feature mapping needed for emerging high-throughput characterization and autonomous microscope platforms.

关键词： systems image enable