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Morphological and microsatellite DNA diversity of Nigerian indigenous sheep

Journal of Animal Science and Biotechnology 2013年第1期4卷 18-33页

作者： Brilliant O Agaviezor Sunday O Peters Mufliat A Adefenwa Abdulmojeed Yakubu Olufunmilayo A Adebambo Michael O Ozoje Christian ON Ikeobi matthew wheto Oyeyemi O Ajayi Samuel A Amusan Oludotun J Ekundayo Timothy M Sanni Moses Okpeku Gbolabo O Onasanya Marcos De Donato Babatunde M Ilori Kadir Kizilkaya Ikhide G Imumorin Department of Animal Breeding and Genetics University of Agriculture Department of Animal Science and Fisheries University of Port Harcourt Dept of Animal Science Cornell University Dept of Animal Science Berry College Department of Cell Biology and Genetics University of Lagos Department of Animal Science Nasarawa State University Dept of Livestock Production Niger Delta University Department of Animal Science Adnan Menderes University

Background： Sheep is important in the socio-economic lives of people around the world. It is estimated that more than half of our once common livestock breeds are now endangered. Since genetic characterization of Nigerian sheep is still lacking, we analyzed ten morphological traits on 402 animals and 15 microsatellite DNA markers in 384 animals of the 4 Nigerian sheep breeds to better understand genetic diversity for breeding management and germplasm conservation. Results： Morphological traits of Uda and Balami were significantly （P 〈 0.05） higher than Yankasa, which were both higher than West African Dwarf （WAD） sheep. Stepwise discriminant analysis showed tail length, rump height, chest girth, ear length and chest depth as the most discriminating variables for classification. Mahalanobis distances show the least differentiation between Uda and Balami and the largest between WAD and Balami sheep. While 93.3% of WAD sheep were correctly assigned to their source genetic group, 63.9% of Yankasa, 61.2% of Balami and 45.2% of Uda were classified correctly by nearest neighbour discriminant analysis. The overall high Polymorphism Information Content （PIC） of all microsatellite markers ranged from 0.751 to 0.927 supporting their use in genetic characterization. Expected heterozygosity was high for all loci （0.783 to 0.93）. Mean heterozygote deficiency across all populations （0.17] to 0.534） possibly indicate significant inbreeding （P 〈 0.05）. Mean values for FST, FIT and F^s statistics across all loci were 0.088, 0.394 and 0.336 respectively. Yankasa and Balami are the most closely related breeds （DA = 0.184） while WAD and Balami are the farthest apart breeds （DA-- 0.665）, which is coincident with distance based on morphological analysis and population structure assessed by STRUCTURE. Conclusions： These results suggest that within-breed genetic variation in Nigerian sheep is higher than between-breeds and may be a valuable tool for genetic improvement and conservation. The

关键词： Discriminant analysis Genetic distance Microsatellite DNA Morphological traits Nigerian sheep

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Differential IFN-Gamma (IFN-γ), Interleukin 10 (IL-10) and Cardiac Troponin I (cTnI) Responses in Natural Bovine Trypanosomosis in Nigeria

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Open Journal of Veterinary Medicine 2016年第7期6卷 105-111页

作者： Michael I. Takeet Benjamin O. Fagbemi Sunday O. Peters matthew wheto Abdulmojeed Yakubu Marcos DeDonato Ikhide G. Imumorin Animal Genetics and Genomics Laboratory International Programs College of Agriculture and Life Sciences Cornell University Ithaca NY USA Department of Veterinary Microbiology and Parasitology Federal University of Agriculture Abeokuta Nigeria Department of Veterinary Microbiology and Parasitology University of Ibadan Ibadan Nigeria Department of Animal Science Berry College Mount Berry GA USA Department of Animal and Dairy Sciences University of Georgia Athens GA USA Department of Animal Breeding and Genetics Federal University of Agriculture Abeokuta Nigeria Department of Animal Science Nasarawa State University Lafia Nigeria Department of Biomedicine Universidad de Oriente Cumana Venezuela

Trypanosomosis is major drawback to profitable livestock production in sub-Sahara African, including Nigeria. Knowledge of the cytokines production in the phase of natural infection may help to better diagnose, treat and prevent bovine trypanosomosis. The purpose of the this study was to determine the levels of interferon-gamma (IFN-γ), interleukin-10 (IL-10) and cardiac troponin–I (cTnI) in the sera of cattle naturally infected with T. brucei, T. congolense and T. vivax and correlate these levels with parasitaemia and PCV of the infected animals. Five milliliter of blood samples were collected via the jugular vein from 411 randomly selected cattle into EDTA and non-citrated bottle. PCV was determined manually using HCT. Trypansomes were detected and characterized by microscopy and PCR, respectively. Serum levels of IFN-γ, IL-10 and cTnI were determined using commercial ELISA kit. Data were summarized using descriptive statistic and significance of differences determined by ANOVA. Of the 62 samples positive for trypanosomes by microscopy, 50 samples were confirmed to species level by PCR. The sera levels of IFN-γ, IL-10 and cTnI of infected cattle were higher than non-infected cattle. The differences were not significant (p γ, IL-10 and cTnI in cattle with natural trypanosomosis. Further investigation is required to understand the specific effect of trypanosomes on myocardiac integrity and interaction between the two cytokines in natural trypanosomosis in cattle.

关键词： Cattle Cardiac Troponin Interferon-Gamma Interleukin-10 Trypanosomosis

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Phylogenetics and Molecular Divergence of Tilapia Fish (Oreochromis Species) Using Mitochondrial D-Loop and Cytochrome b Regions

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American Journal of Molecular Biology 2018年第1期8卷 39-57页

作者： Ekerette Emmanuel Ekerette Ekei Victor Ikpeme Ogbuagu Ugorji Udensi Michael Ohiokhuaobo Ozoje Owoidihe Monday Etukudo Anthony John Umoyen Samuel Olutunde Durosaro matthew wheto Department of Genetics and Biotechnology University of Calabar Calabar Nigeria Department of Animal Breeding and Genetics Federal University of Agriculture Abeokuta Nigeria

Understanding the level of genetic diversity in any population is an important requisite towards strategizing measures for conservation and improvement of stocks. This study focused on the assessment of phylogenetics and molecular divergence of tilapia fish species obtained from two populations (Domita in South-South and Odeda in South-West, Nigeria) using the displacement loop (D-loop) and cytochrome b region of the mitochondrial deoxyribonucleic acid (mtDNA). A total of 28 samples (15 from South-South and 13 from South-West) were used for the genetic analysis. DNA was extracted from the tissue of all the samples using Quik-gDNATM miniPrep kit. The D-loop containing the hypervariable region was sequenced for all samples from the two populations, while cytochrome b (Cyt b) region of mtDNA was only sequenced for samples from South-South population. Chromatograms of the sequences were viewed and edited using Bioedit software. Multiple sequence alignment was carried out using molecular evolutionary genetic analysis (MEGA) software before subsequent genetic analyses. Phylogenetic analysis grouped the samples into two clusters based on population. Also, when the two mitochondrial regions were pooled together, they clustered into two major groups based on mitochondrial regions. Analysis of molecular variance (AMOVA) revealed 37.32% variation within population and 62.68% variation among population with a significant fixation index of 0.627 (p 0.05). The genetic distance inferred between D-loop regions of South-South and South-West populations was 0.243. Maternal lineage analysis revealed that the origin of tilapia fish from both populations could be traced to Oreochromis spirilus and Oreochromis leucostictus based on mitochondrial D-loop region. The findings of this study revealed molecular divergence among the tilapia populations and may serve as pivot information for the genetic improvement of this important species.

关键词： Phylogenetics Molecular Divergence Maternal Lineage Tilapia Fish

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Novel intron 2 polymorphism in the melanophilin gene is in Hardy-Weinberg equilibrium and is not associated with coat color in goats

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Open Journal of Genetics 2013年第3期3卷 195-200页

作者： Mufliat A. Adefenwa Brilliant O. Agaviezor Sunday O. Peters matthew wheto Oludotun J. Ekundayo Moses Okpeku Bola O. Oboh Khalid O. Adekoya Christian O. N. Ikeobi Marcos De Donato Bolaji N. Thomas Ikhide G. Imumorin Department of Animal Breeding and Genetics University of Agriculture Abeokuta Nigeria Department of Animal Science Cornell University Ithaca USA Department of Biomedical Sciences Rochester Institute of Technology Rochester USA Department of Cell Biology and Genetics University of Lagos Lagos Nigeria Department of Livestock Production Niger Delta University Amassomma Nigeria

Pigmentation plays important adaptation and physiological efficiency roles in animals. In the sequence of a 648 bp fragment representing intron 1, exon 2, and part of intron 2 of the MLPH mammalian pigmentation gene, we identified a novel g.469C> G mutation in intron 2, and genotyped it in 266 Nigerian goats using PCR-RFLP analysis. The C allele had frequencies of 0.9625, 0.9804 and 0.97405 in West African Dwarf (WAD),Sahel(SH) and Red Sokoto (RS) breeds, respectively. The G allele was the highest in WAD (0.0375), followed by RS (0.02595), and then SH (0.0196). Overall low FIS and FST and high Nm values demonstrate little differentiation within and among the goat breeds at this intronic locus. This g.469C> G polymorphism in MLPH gene is the first in any goat breed and also first in Nigerian goats. Our results suggest that this intronic SNP locus is maintained at Hardy-Weinberg equilibrium (P < 0.05) and the lack of association of this SNP with coat color may indicate its neutrality in goats.

关键词： Coat Color Goats Melanophilin Nigeria Intron 2 SNP PCR-RFLP

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Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： Christopher J.O’Connell matthew J.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA James L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain injury(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

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Complement-dependent neuroinflammation in spinal cord injury:from pathology to therapeutic implications

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Neural Regeneration Research 2025年第5期20卷 1324-1335页

作者： Hassan Saad Bachar El Baba Ali Tfaily Firas Kobeissy Juanmarco Gutierrez Gonzalez Daniel Refai Gerald R.Rodts Christian Mustroph David Gimbel Jonathan Grossberg Daniel L.Barrow matthew F.Gary Ali M.Alawieh Department of Neurosurgery Emory University School of MedicineAtlantaGAUSA Department of Neurology Yale UniversityNew HavenCTUSA Center for Neurotrauma Multiomics&Biomarkers(CNMB)Morehouse School of MedicineAtlantaGAUSA

Spinal cord injury remains a major cause of disability in young adults,and beyond acute decompression and rehabilitation,there are no pharmacological treatments to limit the progression of injury and optimize recovery in this *** the thorough investigation of the complement system in triggering and propagating cerebral neuroinflammation,a similar role for complement in spinal neuroinflammation is a focus of ongoing *** this work,we survey the current literature investigating the role of complement in spinal cord injury including the sources of complement proteins,triggers of complement activation,and role of effector functions in the *** study relevant data demonstrating the different triggers of complement activation after spinal cord injury including direct binding to cellular debris,and or activation via antibody binding to damage-associated molecular *** effector functions of complement have been implicated in spinal cord injury,and we critically evaluate recent studies on the dual role of complement anaphylatoxins in spinal cord injury while emphasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord *** this pathophysiological review,we systematically review the different translational approaches used in preclinical models of spinal cord injury and discuss the challenges for future translation into human *** review emphasizes the need for future studies to dissect the roles of different complement pathways in the pathology of spinal cord injury,to evaluate the phases of involvement of opsonins and anaphylatoxins,and to study the role of complement in white matter degeneration and regeneration using translational strategies to supplement genetic models.

关键词： complement neuroinflammation neuroplasticity regeneration spinal cord injury targeted therapy

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A MONOTONE DOMAIN DECOMPOSITION ALGORITHM FOR SOLVING WEIGHTED AVERAGE APPROXIMATIONS TO NONLINEAR SINGULARLY PERTURBED PARABOLIC PROBLEMS

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Journal of Computational Mathematics 2008年第1期26卷 76-97页

作者： Igor Boglaev matthew Hardy Institute of Fundamental Sciences Massey UniversityPrivate Bag 11-222Palmerston NorthNew Zealand Mathematical Sciences Institute Australian National UniversityCanberraAustralia 0200

This paper presents and analyzes a monotone domain decomposition algorithm for solving nonlinear singularly perturbed reaction-diffusion problems of parabolic type. To solve the nonlinear weighted average finite difference scheme for the partial differential equation, we construct a monotone domain decomposition algorithm based on a Schwarz alternating method and a box-domain decomposition. This algorithm needs only to solve linear discrete systems at each iterative step and converges monotonically to the exact solution of the nonlinear discrete problem. domain decomposition algorithm is estimated The rate of convergence of the monotone Numerical experiments are presented.

关键词： Parabolic reaction-diffusion problem Boundary layers O-method Monotone domain decomposition algorithm Uniform convergence

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Schreibersite on the early Earth:Scenarios for prebiotic phosphorylation

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Geoscience Frontiers 2017年第2期8卷 329-335页

作者： matthew A.Pasek School of Ceoscience University of South FloridaTampaFL 33620USA

The mineral schreibersite,（Fe,Ni）_3P,provides a reactive source of phosphorus capable of forming phosphorylated *** molecules may have been an important component of prebiotic chemistry,allowing their build-up and eventual commencement of *** here are potential geochemical routes to providing schreibersite,as a potentially important prebiotic mineral,to the Hadean *** routes are identified：delivery of phosphides by meteoritic material and the reduction of phosphates to phosphides by high-temperature,low-redox *** 1-10% of all crustal phosphorus is estimated to have been in schreibersite during the Hadean,making the long-term reaction of this mineral with organic-laden water plausible for many ***,such conditions would have been conducive to the formation of life as we know it today.

关键词： Phosphorus Hadean Meteorites Thermodynamics Origin of life Prebiotic chemistry

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Acoustic Velocities and Elastic Properties of Pyrite (FeS2) to 9.6 GPa

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Journal of Earth Science 2010年第5期21卷 792-800页

作者： matthew L Whitaker Mineral Physics Institute Stony Brook University Geodynamics Research Center Ehime University

Ultrasonic interferometry was utilized in conjunction with synchrotron-based X-ray diffraction and X-radiographic imaging to determine the compressional and shear wave velocities and unlt-cdl volumes of pyrite （FeS2） at room temperature and pressures up to 9.6 GPa. Fitting all of the experimental volume and velocity data to third-order finite-strain equations yielded the adiabatic zero-pressure bulk and shear moduli and their first pressure derivatives： Ks0=138.9（7） GPa, Go=U2.3（3） GPa, （δKS0/δP）T=KS0＇=6.0（1）, （δG0/δP）T=G0＇=3.0（〈1）, where the numbers in parentheses represent the 1δ uncertainty in the last significant digit. These results are in good agreement with several previous static compression studies on this material but differ quite strongly from the results obtained via first principles calculations. This study presents the first direct measurement of the bulk shear properties of this material.

关键词： mineral physics ultrasonic interferometry high pressure iron sulfide elastic property equation of state.

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Parametric computational study on butterfly-shaped hysteretic dampers

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Frontiers of Structural and Civil Engineering 2019年第5期13卷 1214-1226页

作者： Alireza FARZAMPOUR matthew Roy EATHERTON Department of Civil and Environmental Engineering Virginia TechBlacksburgVA 24060USA

A parametric computational study is conducted to investigate the shear yielding, flexural yielding, and lateral torsional buckling limit states for butterfly-shaped links. After validating the accuracy of the finite element modeling approach against previous experiments, 112 computational models with different geometrical properties were constructed and analyzed including consideration of initial imperfections. The resulting yielding moment, corresponding critical shear force, the accumulation of plastic strains through the length of links as well as the amount of energy dissipated are investigated. The results indicate that as the shape of the butterfly-shaped links become too straight or conversely too narrow in the middle, peak accumulated plastic strains increase. The significant effect of plate thickness on the buckling limit state is examined in this study. Results show that overstrength for these links (peak force divided by yield force) is between 1.2 and 4.5, with straight links producing larger overstrength. Additionally, proportioning the links to delay buckling, and designing the links to yield in the flexural mode are shown to improve energy dissipation.

关键词： structural fuse hystcretic damper finite element analysis energy dissipation initial imperfection butterfly-shaped links

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