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Folate and vitamin B12 in idiopathic male infertility

Asian Journal of Andrology 2011年第6期13卷 856-861页

作者： laurel e murphy James L Mills Anne M Molloy Cong Qian Tonia C Carter Helena Strevens Dag Wide-Swensson Aleksander Giwercman Richard J Levine Division of epidemiology Statistics and Prevention Research Eunice Kennedy Shriver National Institute of Child Health and Human Development Bethesda MD 20892 USA School of Medicine Trinity College Dublin Dublin Ireland Glotech Inc Rockville MD 20850 USA Department of Obstetrics and Gynecology Sk~ne University Hospital in Lund Lund University S-221 85 Lund Sweden Reproductive Medicine Centre Skane University Hospital Maimo Lund University S-205 02 Malmo Sweden

Although methylenetetrahydrofolate reductase, a folate enzyme gene, has been associated with idiopathic male infertility, few studies have examined other folate-related metabolites and genes. We investigated whether idiopathic male infertility is associated with variants in folate, vitamin B12 （B12） and total homocysteine （tHcy）-related genes and measured these metabolites in blood. We conducted a case-control study that included 153 men with idiopathic infertility and 184 fertile male controls recruited at the Fertility Center and Antenatal Care Center, University Hospital, Malmo and Lund, Sweden. Serum folate, red cell folate （RCF）, serum B12, plasma tHcy and semen quality were measured. Subjects were genotyped for 20 common variants in 12 genes related to folate/B12/ homocysteine metabolism. Metabolite concentrations and genotype distributions were compared between cases and controls using linear and logistic regression with adjustment for covariates. The phosphatidylethanolamine N-methyltransferase （PeMT） M 175V and TCblR rs173665 polymorphisms were significantly associated with infertility （P=0.01 and P=0.009, respectively）, but not with semen quality. Among non-users of supplements, infertile men had lower serum folate concentrations than fertile men （12.89 vs. 14.73 nmoll^- 1 P=0.02）, but there were no significant differences in RCF, B 12 or tHcy. Folate, B 12 and tHcy concentrations were not correlated with any semen parameters. This study provides little support for low folate or B12 status in the pathogenesis of idiopathic male infertility. Although additional data are needed to confirm these initial findings, our results suggest that PeMTand TCbIR, genes involved in choline and B12 metabolism, merit further investigation in idiopathic male infertility.

关键词： folate idiopathic male infertility semen quality vitamin B12

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CONTROLLeD ANIONIC SYNTHeSIS OF FUNCTIONALIZeD AND STAR-BRANCHeD POLYMeRS

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Chinese Journal of Polymer Science 1990年第2期8卷 97-107页

作者： RODeRIC P. QUIRK GABRIeL SUMMeRS KIM Jungahn laurel e. SCHOCK Institute of Polymer Science University of Akron Akron Ohio 44325 U. S. A.Institute of Polymer Science University of Akron Akron Ohio 44325 U. S. A.Institute of Polymer Science University of Akron Akron Ohio 44325 U. S. A.Institute of Polymer Science University of Akron Akron Ohio 44325 U. S. A.

The use of living, alkyllithium-initiated anionic polymerization to prepare chain-end functionalized polymers and heteroarm, star-branched polymers is discussed. The scope and limitations of specific termination reactions with a variety of electrophilic species are illustrated for carbonation, hydroxyethylation, amination, and sulfonation. The methodology of using substituted 1,1-diphenylethylenes to provide a general, quantitative functionalization procedure is outlined and illustrated with examples of amine and phenol end-functionalization. A methodology is described for the synthesis of functionalized, star-branched copolymers with compositionally heterogeneous arms of controlled molecular weight and narrow molecular weight distribution using 1, 3-bis(1-pbenylethenyl) benzene.

关键词： Poly CONTROLLeD ANIONIC SYNTHeSIS OF FUNCTIONALIZeD AND STAR-BRANCHeD POLYMeRS STAR

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Dermal fibroblast expression of stromal cellderived factor-1 （SDF-1） promotes epidermal keratinocyte proliferation in normal and diseased skin

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Protein & Cell 2015年第12期6卷 890-903页

作者： Chunji Quan Moon Kvun Cho Yuan Shao laurel e. Mianecki eric Liao Daniel Perry Taihao Quan Department of Pathology Affiliated Hospital of Yanbian University Yanji 133000 China Department of Dermatology Soonchunhyang University College of Medicine Seoul Republic of Korea Hollings Cancer Center Biorepository and Tissue Analysis Resource Medical University of South Carolina Charleston SC 29425 USA Department of Dermatology University of Michigan Medical School Ann Arbor MI 48109 USA

Stromal cells provide a crucial microenvironment for overlying epithelium. Here we investigated the expression and function of a stromal cell-specific protein, stromal cell-derived factor-1 （SDF-1）, in normal human skin and in the tissues of diseased skin. Immunohistology and laser capture microdissection （LCM）-coupled quantitative real- time RT-PCR revealed that SDF-1 is constitutively and predominantly expressed in dermal stromal cells in nor- mal human skin in vivo. To our surprise, an extremely high level of SDF-1 transcription was observed in the dermis of normal human skin in vivo, evidenced by much higher mRNA expression level than type I collagen, the most abundant and highly expressed protein in human skin. SDF-1 was also upregulated in the tissues of many human skin disorders including psoriasis, basal cell carcinoma （BCC）, and squamous cell carcinoma （SCC）. Double immunostaining for SDF-1 and HSP47 （heat shock protein 47）, a marker of fibroblasts, revealed that fibroblasts were the major source of stroma-cell-derived SDF-1 in both normal and diseased skin. Functionally, SDF-1 activates the eRK （extracellular-signal-regulated kinases） pathway and functions as a mitogen to stimulate epidermalkeratinocyte proliferation. Both overexpression of SDF-1 in dermal fibroblasts and treatment with rhSDF-1 to the skin equivalent cultures significantly increased the number of keratinocyte layers and epidermal thickness. Con- versely, the stimulative function of SDF-1 on keratinocyte proliferation was nearly completely eliminated by inter- fering with CXCR4, a specific receptor of SDF-1, or by knock-down of SDF-1 in fibroblasts. Our data reveal that extremely high levels of SDF-1 provide a crucial microenvironment for epidermal keratinocyte proliferation in both physiologic and pathologic skin conditions.

关键词： SDF-1 dermal fibroblast keratinocyte,proliferation skin cancer psoriasis

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Tissue engineering in mandibular reconstruction: osteogenesis-inducing scaffolds

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Plastic and Aesthetic Research 2019年第9期6卷 1-12页

作者： laurel Nelms William Jack Palmer University of California Riverside School of Medicine RiversideCA 92521USA Boston University School of Medicine BostonMA 02118USA.

Currently, the gold standard for aesthetic and functional reconstruction of critical mandibular defects is an autologous fibular flap;however, this carries risk of donor site morbidity, and is not a promising option in patients with depleted donor sites due to previous surgeries. Tissue engineering presents a potential solution in the design of a biomimetic scaffold that must be osteoconductive, osteoinductive, and support osseointegration. These osteogenesis-inducing scaffolds are most successful when they mimic and interact with the surrounding native macro- and micro-environment of the mandible. This is accomplished via the regeneration triad: (1) a biomimetic, bioactive osteointegrative scaffold, most likely a resorbable composite of collagen or a synthetic polymer with collagen-like properties combined with beta-tri calcium phosphate that is 3D printed according to defect morphology;(2) growth factor, most frequently bone morphogenic protein 2 (BMP-2);and (3) stem cells, most commonly bone marrow mesenchymal stem cells. Novel techniques for scaffold modification include the use of nano-hydroxyapatite, or combining a vector with a biomaterial to create a gene activated matrix that produces proteins of interest (typically BMP-2) to support osteogenesis. Here, we review the current literature in tissue engineering in order to discuss the success of varying use and combinations of scaffolding materials (i.e., ceramics, biological polymers, and synthetic polymers) with stem cells and growth factors, and will examine their success in vitro and in vivo to induce and guide osteogenesis in mandibular defects.

关键词： Osteogenic scaffolds mandibular reconstruction tissue engineering regeneration triad bone morphogenic protein bone marrow mesenchymal stem cells beta-tri calcium phosphate gene activated matrix

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The compelling link between physical activity and the body's defense system

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Journal of Sport and Health Science 2019年第3期8卷 201-217页

作者： David C.Nieman laurel M.Wentz Human Performance Laboratory Appalachian State University North Carolina Research Campus Department of Nutrition and Health Care Management Appalachian State University

This review summarizes research discoveries within 4 areas of exercise immunology that have received the most attention from investigators :(1) acute and chronic effects of exercise on the immune system,(2) clinical benefits of the exercise—immune relationship,(3) nutritional influen?ces on the immune response to exercise, and(4) the effect of exercise on immunosenescence. These scientific discoveries can be organized into distinctive time periods: 1900-1979, which focused on exercise-induced changes in basic immune cell counts and function; 1980-1989, during which seminal papers were published with evidence that heavy exertion was associated with transient immune dysfunction, elevated inflammatory biomarkers,and increased risk of upper respiratory tract infections; 1990-2009, when additional focus areas were added to the field of exercise immunology including the interactive effect of nutrition, effects on the aging immune system, and inflammatory cytokines; and 2010 to the present, when technological advances in mass spectrometry allowed system biology approaches(i.e., metabolomics, proteomics, lipidomics, and microbiome characterization) to be applied to exercise immunology studies. The future of exercise irmmunology will take advantage of these technologies to provide new insights on the interactions between exercise, nutrition, and immune function, with application down to the person?alized level. Additionally, these methodologies will improve mechanistic understanding of how exercise-induced immune perturbations reduce the risk of common chronic diseases.

关键词： Aging exercise Immunology Infection Inflammation Mass Snectrometry Nutrition

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High-fructose corn syrup production and its new applications for 5-hydroxymethylfurfural and value-added furan derivatives:Promises and challenges

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Journal of Bioresources and Bioproducts 2022年第3期7卷 148-160页

作者： Aristide laurel Mokale Kognou Sarita Shrestha Zihua Jiang Chunbao(Charles)Xu Fubao Sun Wensheng Qin Department of Biology Lakehead UniversityThunder Bay P7B 5E1Canada Department of Chemistry Lakehead UniversityThunder Bay P7B 5E1Canada Department of Chemical and Biochemical engineering Western UniversityLondon N6A 5B9Canada School of Biotechnology Jiangnan UniversityWuxi 214122China

High fructose corn syrup has been industrially produced by converting glucose to fructose by glucose isomerases,tetrameric metalloenzymes widely used in industrial *** in enzyme engineering and commercial production of glucose isomerase have paved the way to explore more efficient variants of these *** 5-hydroxymethylfurfural can be produced from high fructose corn syrup catalytic dehydration,and it can be further converted into various furanic compounds chemically or biologically for various industrial applications as a promising platform *** the chemical conversion of 5-hydroxymethylfurfural into furanic compounds has been extensively investigated in recent years,bioconversion has shown promise for its mild conditions due to the harsh chemical reaction *** review discusses pro-tein engineering potential for improving glucose isomerase production and recent advancements in bioconversion of 5-hydroxymethylfurfural into value-added furanic *** suggests bi-ological strategies for the industrial transformation of 5-hydroxymethylfurfural.

关键词： High fructose corn syrup Glucose isomerase Rational enzyme engineering Directed evolution Furanic derivatives Biocatalysts

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Using Yoga to Reduce Stress and Bullying Behaviors among Urban Youth

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Health 2017年第3期9卷 409-424页

作者： erin e. Centeio laurel Whalen erica Thomas Noel Kulik Nate McCaughtry Department of Kinesiology Health and Sport Studies Wayne State University Detroit MI USA

Background/Purpose: Obesity and secondary conditions continue to disproportionally affect the health of children living in urban areas. Studies show that a lack of resources and physical activity-unfriendly communities discourage 60 minutes of daily activity, including strengthening exercises, as recommended by the Centers for Disease Control and Prevention. Using Social ecological theory, the purpose of this study was to examine the multi-level influences of a yoga-based intervention on urban, inner city youth. Method: Using a mixed-methods design, ninety-three 3 - 5th grade students at five urban elementary schools participated in a ten-week yoga intervention. Analysis/Results: RM-ANOVA results revealed a significant reduction in stress and bullying behaviors among participants, and multiple regression analyses revealed that program attendance, change in stress, and change in yoga enjoyment significantly predicted change in yoga participation outside Pe, when controlling for gender and age F(5, 87) = 5.36, p R2 = 0.19, but did not have a significant impact on physical activity participation outside of school. Student interviews and non-participant observations revealed strong enjoyment of yoga which led students to report substantial increases in yoga-related activities outside of school. Students also revealed that experience in yoga improved focus, attention, and reduced stress. Conclusions: Through convergence of qualitative and quantitative methods, this study showed a positive relationship between the number of yoga sessions attended (dose), enjoyment of yoga, and participation in yoga outside Pe with friends and family. Findings suggest that urban Pe should include more individual, non-competitive activities such as yoga, which students find to be stress-relieving, fun, inexpensive and easy to perform at home.

关键词： Yoga Physical education Stress Physical Activity Bullying

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Characterization of glucose isomerase-producing bacteria and optimization of fermentation conditions for producing glucose isomerase using biomass

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Green Chemical engineering 2023年第2期4卷 239-249页

作者： Aristide laurel Mokale Kognou Chonlong Chio Janak Raj Khatiwada Sarita Shrestha Xuantong Chen Hongwei Li Yuen Zhu Zi-Hua Jiang Chunbao(Charles)Xu Wensheng Qin Department of Biology Lakehead UniversityThunder BayONP7B 5E1Canada Department of Chemical and Biochemical engineering Western UniversityLondonONN6A 5B9Canada School of environment and Resources Shanxi UniversityTaiyuan030006China Department of Chemistry Lakehead UniversityThunder BayONP7B 5E1Canada

Glucose isomerase(GI)is an enzyme with high potential *** of GI producing bacteria with interesting properties from an industrial point of view is *** sp.,Paenarthrobacter sp.,Chryseobacterium sp.,Hymenobacter sp.,Mycobacterium sp.,and Stenotrophomonas *** isolated from soil *** of enzyme production yield was investigated in various fermentation conditions using response surface *** isolates exhibited maximum GI activity at 40℃,pH 6–8 after 4 days of incubation.A mixture of peptone/yeast extract or tryptone/peptone enhanced higher enzyme *** same trend was observed in fermentation medium containing 1%xylose or 2%–2.5%wheat *** study advanced the knowledge of these bacterial isolates in promoting wheat straw as feedstock for the bio-based industry.

关键词： Cellulolytic bacteria Glucose/xylose isomerase 16S rRNA Biomass conversion

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A robust new metric of phenotypic distance to estimate and compare multiple trait differences among populations

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Current Zoology 2012年第3期58卷 426-439页

作者： Rebecca SAFRAN Samuel FLAXMAN Michael KOPP Darren e. IRWIN Derek BRIGGS Matthew R. eVANS W. Chris FUNK David A. GRAY eileen A. HeBeTS Nathalie SeDDON elizabeth SCORDATO laurel B. SYMeS Joseph A. TOBIAS David P. L. TOeWS J. Albert C. UY Department of ecology and evolutionary Biology University of Colorado Boulder CO 80309 U.S.A. Mathematics and B iosciences Group Faculty of Mathematics University of Vienna A-1090 Vienna Austria Current address evolutionary Biology and Modeling Group Faculty of Sciences Aix-Marseille University 13331 Marseille France. Department of Zoology University of British Columbia 6270 University Boulevard Vancouver BC Canada V6T 1Z4. Research ＆ evaluation Methodology School of Education University of Colorado Boulder CO 80309 U.S.A. School of Biological and Chemical Sciences Queen Mary University of London London E1 4NS Department of Biology Colorado State University Fort Collins CO 80523 U.S.A. Department of Biology California State University Northridge CA 91330 U.S.A. School of Biological Sciences University of Nebraska Lincoln NE 68588 U.S.A. edward Grey Institute Department of Zoology University of Oxford Oxford OX1 3PS UK Committee on evolutionary Biology The University of Chicago Chicago IL 60637U.S.A. Department of Biology Dartmouth College Hanover NH 03755 U.S.A. Department of Biology University of Miami Coral Gables FL 33146 U.S.A.

Whereas a rich literature exists for estimating population genetic divergence, metrics of phenotypic trait divergence are lacking, particularly for comparing multiple traits among three or more populations. Here, we review and analyze via simula- tion Hedges＇ g, a widely used parametric estimate of effect size. Our analyses indicate that g is sensitive to a combination of unequal trait variances and unequal sample sizes among populations and to changes in the scale of measurement. We then go on to derive and explain a new, non-parametric distance measure, ＇Aft＇, which is caiculated based upon a joint cumulative distribution function （CDF） from all populations under study. More precisely, distances are measured in terms of the percentiles in this CDF at which each population＇s median lies. Ap combines many desirable features of other distance metrics into a single metric; namely, compared to other metrics, p is relatively insensitive to unequal variances and sample sizes among the populations sam- pied. Furthermore, a key feature of Ap--and our main motivation for developing it--is that it easily accommodates simultaneous comparisons of any number of traits across any number of populations. To exemplify its utility, we employ Ap to address a ques- tion related to the role of sexual selection in speciation： are sexual signals more divergent than ecological traits in closely related taxa？ Using traits of known function in closely related populations, we show that traits predictive of reproductive performance are indeed, more divergent and more sexually dimorphic than traits related to ecological adaptation [Current Zoology 58 （3）： 426-439 2012].

关键词： effect size Phenotype divergence Sexual dimorphism Sexual selection Speciation

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Just writing :grammar, punctuation, and style for the legal writer 3rd ed. 3rd ed.

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2009年

作者： Anne enquist laurel Currie Oates

来源：畅想之星图书光盘版（南... 评论

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