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The genetics of pediatric inflammatory bowel disease:Towards precision medicine
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作者 AHMAD SHAHIR MOHAMAD NAZRI NAZIHAH MOHD YUNUS MARAHAINI MUSA 《BIOCELL》 2025年第1期149-160,共12页
Pediatric inflammatory bowel disease(IBD)is a chronic and heterogeneous disease.IBD is commonly classified into Crohn’s disease and ulcerative colitis.It is linked to serious symptoms and complications.The onset of I... Pediatric inflammatory bowel disease(IBD)is a chronic and heterogeneous disease.IBD is commonly classified into Crohn’s disease and ulcerative colitis.It is linked to serious symptoms and complications.The onset of IBD commonly occurs during adolescence.Despite the significant number of cases globally(~5 million),the causes of pediatric IBD,which constitutes 25%of IBD patients,are not yet fully understood.Apart from environmental factors,genetic factors contribute to a higher risk of developing IBD.The predisposition risk of IBD can be investigated using genetic testing.Genetic mechanisms of pediatric IBD are highly complex which resulted in difficulty in selecting effective treatment or patient management.Genetic variation of IBD would serve as a basis for precision medicine and allow for the discovery of more robust treatment avenues for this condition in pediatric patients.This review aims to discuss the genetics of pediatric IBD,and current development in the screening,diagnosis,and treatment based on genetic profiling of pediatric IBD subjects toward more personalized management of this disease. 展开更多
关键词 genetics Inflammatory bowel disease Personalized medicine
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Metalloproteinases as mediators of inflammation and the eyes: molecular genetic underpinnings governing ocular pathophysiology 被引量:2
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作者 Mahavir Singh Suresh C Tyagi 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第8期1308-1318,共11页
There are many vision threatening diseases of the eye affecting millions of people worldwide. In this article, we are summarizing potential role of various matrix metalloproteinases (MMPs); the Zn (2+)-dependent ... There are many vision threatening diseases of the eye affecting millions of people worldwide. In this article, we are summarizing potential role of various matrix metalloproteinases (MMPs); the Zn (2+)-dependent endoproteases in eye health along with pathogenesis of prominent ocular diseases such as macular degeneration, diabetic retinopathy, and glaucoma via understanding MMPs regulation in affected patients, interactions of MMPs with their substrate molecules, and key regulatory functions of tissue inhibitor of metalloproteinases (TIMPs) towards maintaining overall homeostasis. 展开更多
关键词 age-related macular degeneration choroidal neovascularization diabetes GLAUCOMA metalloproteinases tissue inhibitors of metalloproteinases
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An efficient method for constructing a random insertional mutant library for forward genetics in Nannochloropsis oceanica
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作者 Zhongyi ZHANG Hang LIU +5 位作者 Xiaohui PAN Yanan ZONG Leili FENG Lixian LIU Li GUO Guanpin YANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期216-225,共10页
Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-st... Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-strand breaks of DNA,causing insertional mutation.The random insertional mutant library constructed using this method has become a method of forward genetics for gene cloning.However,the establishment of a random insertional mutant library requires a high transformation efficiency of exogenous genes.Many microalgal species show a low transformation efficiency,making constructing random insertional mutant libraries difficult.In this study,we established a highly efficient transformation method for constructing a random insertional mutant library of Nannochloropsis oceanica,and tentatively tried to isolate its genes to prove the feasibility of the method.A gene that may control the growth rate and cell size was identified.This method will facilitate the genetic studies of N.oceanica,which should also be a reference for other microalgal species. 展开更多
关键词 Nannochloropsis oceanica genetic transformation random insertional mutant library zeocin pretreatment forward genetics
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Placenta-derived mesenchymal stem cells attenuate secondary brain injury after controlled cortical impact in rats by inhibiting matrix metalloproteinases
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作者 PING YANG YUANXIANG LAN +2 位作者 ZHONG ZENG YAN WANG HECHUN XIA 《BIOCELL》 SCIE 2024年第1期149-162,共14页
Background:As a form of biological therapy,placenta-derived mesenchymal stem cells(PDMSCs)exhibit considerable promise in addressing the complex pathological processes of traumaticbrain injury(TBI)due to their multi-t... Background:As a form of biological therapy,placenta-derived mesenchymal stem cells(PDMSCs)exhibit considerable promise in addressing the complex pathological processes of traumaticbrain injury(TBI)due to their multi-target and multi-pathway mode of action.Material&Methods:This study investigates the protective mechanisms and benefits of PDMSCs in mitigating the effects of controlled cortical impact(CCI)in rats and glutamate-induced oxidative stress injury in HT22 cells in vitro.Our primary objective is to provide evidence supporting the clinical application of PDMSCs.Results:In the in vivo arm of our investigation,we observed a swift elevation of matrix metalloproteinase-9(MMP-9)in the proximal cortex of injured brain tissues after CCI.PDMSCs,distinguished by their heightened expression of metalloproteinase tissue inhibitors-1 and-2(TIMP-1 and TIMP-2):were intravenously administered via the caudal vein.This intervention yielded significant reductions in the permeability of the blood-brain barrier(BBB):the extent of brain edema,the levels of inflammatory cytokines IL-1βand TNF-αin damaged brain tissue,and the activation status of microglia in CCI-afflicted rats.In the realm of in vitro experiments,PDMSC-conditioned media demonstrated substantial reductions in mortality rates and cleaved caspase-3 levels in glutamate-induced HT22 cells compared with conventional media.Notably,this advantage was negated upon the introduction of neutralizing antibodies targeting TIMP-1 and TIMP-2.Conclusion:Collectively,our findings underscore the potential of PDMSCs in alleviating oxidative stress injury and secondary brain injury in the pathological process of TBI. 展开更多
关键词 Traumatic brain injury Mesenchymal stem cells Oxidative stress Matrix metalloproteinases
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Matrix metalloproteinases in neural development:a phylogenetically diverse perspective 被引量:1
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作者 Christopher D.Small Bryan D.Crawford 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第3期357-362,共6页
The matrix metalloproteinases(MMPs) are a family of zinc-dependent endopeptidases originally characterized as secreted proteases responsible for degrading extracellular matrix proteins.Their canonical role in matrix... The matrix metalloproteinases(MMPs) are a family of zinc-dependent endopeptidases originally characterized as secreted proteases responsible for degrading extracellular matrix proteins.Their canonical role in matrix remodelling is of significant importance in neural development and regeneration,but emerging roles for MMPs,especially in signal transduction pathways,are also of obvious importance in a neural context.Misregulation of MMP activity is a hallmark of many neuropathologies,and members of every branch of the MMP family have been implicated in aspects of neural development and disease.However,while extraordinary research efforts have been made to elucidate the molecular mechanisms involving MMPs,methodological constraints and complexities of the research models have impeded progress.Here we discuss the current state of our understanding of the roles of MMPs in neural development using recent examples and advocate a phylogenetically diverse approach to MMP research as a means to both circumvent the challenges associated with specific model organisms,and to provide a broader evolutionary context from which to synthesize an understanding of the underlying biology. 展开更多
关键词 matrix metalloproteinases extracellular matrix xenopus Drosophila zabrafish neural development evolution
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Interaction between diet and genetics in patients with inflammatory bowel disease
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作者 Daniéla Oliveira Magro Ligia Yukie Sassaki Júlio Maria Fonseca Chebli 《World Journal of Gastroenterology》 SCIE CAS 2024年第12期1644-1650,共7页
In this editorial,we comment on the article by Marangoni et al,published in the recent issue of the World Journal of Gastroenterology 2023;29:5618-5629,about“Diet as an epigenetic factor in inflammatory bowel disease... In this editorial,we comment on the article by Marangoni et al,published in the recent issue of the World Journal of Gastroenterology 2023;29:5618-5629,about“Diet as an epigenetic factor in inflammatory bowel disease”.The authors emphasized the role of diet,especially the interaction with genetics,in promoting the inflam-matory process in inflammatory bowel disease(IBD)patients,focusing on DNA methylation,histone modifications,and the influence of microRNAs.In this editorial,we explore the interaction between genetics,gut microbiota,and diet,in an only way.Furthermore,we provided dietary recommendations for patients with IBD.The Western diet,characterized by a low fiber content and deficiency the micronutrients,impacts short-chain fatty acids production and may be related to the pathogenesis of IBD.On the other hand,the consumption of the Mediter-ranean diet and dietary fibers are associated with reduced risk of IBD flares,particularly in Crohn’s disease(CD)patients.According to the dietary guidance from the International Organization for the Study of Inflammatory Bowel Diseases(IOIBD),the regular consumption of fruits and vegetables while reducing the consumption of saturated,trans,dairy fat,additives,processed foods rich in maltodextrins,and artificial sweeteners containing sucralose or saccharine is recommended to CD patients.For patients with ulcerative colitis,the IOIBD recommends the increased intake of natural sources of omega-3 fatty acids and follows the same restrictive recommendations aimed at CD patients,with the possible inclusion of red meats.In conclusion,IBD is a complex and hetero-geneous disease,and future studies are needed to elucidate the influence of epigenetics on diet and microbiota in IBD patients. 展开更多
关键词 DIET genetics MICRORNAS Gastrointestinal microbiome Inflammatory bowel diseases Crohn’s disease
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A Theory of Bio-Quantum Genetics
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作者 Jianzhong Zhao 《Journal of Quantum Information Science》 CAS 2024年第1期15-27,共13页
The physical mechanism of heredity or inheritance of genes is a quantum mechanical and/or quantum computational process. A theory of bio-quantum genetics is established in this paper. Principle of Bio-quantum Genetics... The physical mechanism of heredity or inheritance of genes is a quantum mechanical and/or quantum computational process. A theory of bio-quantum genetics is established in this paper. Principle of Bio-quantum Genetics is suggested. I propose and define the soft-genes of genetics controlling the processes of heredity or inheritance of genes. This research deals with the quantum mechanisms of Mendel plant heredity and family inheritance as examples of bio-quantum genetics, deepening our understanding of heredity or inheritance. I believe that more contributions will be made to promote researches of bio-quantum genetics or quantum biology at large. 展开更多
关键词 Bio-Quantum genetics Quantum Mechanics GENES Soft Genes Quantum Mechanism of Mendel Plant Heredity Quantum Mechanism of Family Inheritance
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The Practice and Exploration of Applying EBM to Bilingual Teaching of Medical Genetics at OSBCM
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作者 Rong Liu Huaming Zuo 《Open Journal of Applied Sciences》 2024年第4期983-990,共8页
In the process of teaching medical genetics of undergraduate clinical medicine, the practice and exploration of applying EBM to the bilingual teaching of OSBCM medical genetics are carried out. Using CBL and PBL as th... In the process of teaching medical genetics of undergraduate clinical medicine, the practice and exploration of applying EBM to the bilingual teaching of OSBCM medical genetics are carried out. Using CBL and PBL as the carrier can make up for the shortcomings of a single teaching mode, synthesize the advantages of multiple teaching modes. It starts from integrating the basic theoretical knowledge of medicine and clinical practice knowledge, improving students’ bilingual level of medical genetics, cultivating students’ literature retrieval ability, and promoting early clinical, multi-clinical and repeated clinical consciousness for medical students. Therefore, it is more conducive to cultivate students’ ability to learn independently, accurately analyze and solve problems, improve medical students’ clinical thinking ability and scientific research awareness, improve medical students’ ability of international communication, and lay a solid foundation for improving medical students’ future post competence, innovative spirit and lifelong learning ability. 展开更多
关键词 Medical genetics Evidence Based Medicine Organ-System-Based Curriculum Model Problem Based Learning Case-Based Learning
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Prenatal ultrasonography and genetic analysis of fetal cleidocranial dysplasia:A case report
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作者 Feng Wang Pei-Feng Dai Wen-Juan Gao 《World Journal of Clinical Cases》 SCIE 2025年第10期28-34,共7页
BACKGROUND Cleidocranial dysplasia(CCD)is an infrequent clinical condition with an autosomal dominant inheritance pattern.It is characterized by abnormal clavicles,patent sutures and fontanelles,supernumerary teeth,an... BACKGROUND Cleidocranial dysplasia(CCD)is an infrequent clinical condition with an autosomal dominant inheritance pattern.It is characterized by abnormal clavicles,patent sutures and fontanelles,supernumerary teeth,and short stature.Approximately 60%-70%of patients with CCD have mutations in the RUNX family transcription factor 2 gene.However,prenatal diagnosis of CCD is difficult when the family history is unknown.CASE SUMMARY We report a rare case of fetal CCD with an unknown family history,confirmed by prenatal ultrasonography and genetic testing at a gestational age of 16 weeks.The genetic reports indicated that the fetus carried pathogenic mutations in the RUNX family transcription factor 2 gene(c.674G>A).After careful consideration,the pregnant woman and her family decided to continue the pregnancy.CONCLUSION Definitive prenatal diagnosis of CCD should include family history,ultrasound diagnosis,and genetic analysis,especially if family history is unknown. 展开更多
关键词 Cleidocranial dysplasia genetic analysis Ultrasonic diagnosis PRENATAL Case report
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Immunohistochemical expression of matrix metalloproteinase-9 and 13 in oral squamous cell carcinoma and their role in predicting lymph node metastasis
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作者 Bhari Sharanesha Manjunatha Keshav T Handge +2 位作者 Vandana Sandeep Shah Yasser Eid Al-Thobaiti Deepak Gowda Sadashivappa Pateel 《World Journal of Methodology》 2025年第2期108-116,共9页
BACKGROUND One of the main characteristics of oral squamous cell carcinoma(OSCC)is that it metastasizes to cervical lymph nodes frequently with a high degree of local invasiveness.A primary feature of malignant tumors... BACKGROUND One of the main characteristics of oral squamous cell carcinoma(OSCC)is that it metastasizes to cervical lymph nodes frequently with a high degree of local invasiveness.A primary feature of malignant tumors is their penetration of neighboring tissues,such as lymphatic and blood arteries,due to the tumor cells'capacity to break down the extracellular matrix(ECM).Matrix metalloproteinases(MMPs)constitute a family of proteolytic enzymes that facilitate tissue remodeling and the degradation of the ECM.MMP-9 and MMP-13 belong to the group of extracellular matrix degrading enzymes and their expression has been studied in OSCC because of their specific functions.MMP-13,a collagenase family member,is thought to play an essential role in the MMP activation cascade by breaking down the fibrillar collagens,whereas MMP-9 is thought to accelerate the growth of tumors.Elevated MMP-13 expression has been associated with tumor behavior and patient prognosis in a number of malignant cases.AIM To assess the immunohistochemical expression of MMP-9 and MMP-13 in OSCC.METHODS A total of 40 cases with histologically confirmed OSCC by incisional biopsy were included in this cross-sectional retrospective study.The protocols for both MMP-9 and MMP-13 immunohistochemical staining were performed according to the manufacturer’s recommendations along with the normal gingival epithelium as a positive control.All the observations were recorded and Pearson’sχ²test with Fisher exact test was used for statistical analysis.RESULTS Our study showed no significant correlation between MMP-9 and MMP-13 staining intensity and tumor size.The majority of the patients were in advanced TNM stages(III and IV),and showed intense expression of MMP-9 and MMP-13.CONCLUSION The present study suggests that both MMP-9 and MMP-13 play an important and independent role in OSCC progression and invasiveness.Intense expression of MMP-9 and MMP-13,irrespective of histological grade of OSCC,correlates well with TNM stage.Consequently,it is evident that MMP-9 and MMP-13 are important for the invasiveness and progression of tumors.The findings may facilitate the development of new approaches for evaluating lymph node metastases and interventional therapy techniques,hence enhancing the prognosis of patients diagnosed with OSCC. 展开更多
关键词 Matrix metalloproteinases Oral squamous cell carcinoma Tumor staging IMMUNOHISTOCHEMISTRY INVASION Lymph node metastasis TNM stage
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Genetic insights in infectious diseases:Insights from a case report and implications for personalized medicine
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作者 Suryasnata Bhowmik Adrija Hajra Dhrubajyoti Bandyopadhyay 《World Journal of Clinical Cases》 2025年第13期1-6,共6页
The relationship between genetics and infectious diseases is important in shaping our understanding of disease susceptibility,progression,and treatment.Recent research shows the impact of genetic variations,such as he... The relationship between genetics and infectious diseases is important in shaping our understanding of disease susceptibility,progression,and treatment.Recent research shows the impact of genetic variations,such as heme-oxygenase promoter length,on diseases like malaria and sepsis,revealing both protective and inconclusive effects.Studies on vaccine responses highlight genetic markers like human leukocyte antigens,emphasizing the potential for personalized immunization strategies.The ongoing battle against drug-resistant tuberculosis(TB)illustrates the complexity of genomic variants in predicting resistance,highlighting the need for integrated diagnostic tools.Additionally,genome-wide association studies reveal antibiotic resistance mechanisms in bacterial genomes,while host genetic polymorphisms,such as those in solute carrier family 11 member 1 and vitamin D receptor,demonstrate their role in TB susceptibility.Advanced techniques like metagenomic next-generation sequencing promise detailed pathogen detection but face challenges in cost and accessibility.A case report involving a highly virulent Mycobacterium TB strain with the pks1 gene further highlights the need for genetic insights in understanding disease severity and developing targeted interventions.This evolving landscape emphasizes the role of genetics in infectious diseases,while also addressing the need for standardized studies and accessible technologies. 展开更多
关键词 genetic profiling Infectious diseases Tuberculosis virulence pks1 gene genetic polymorphisms Personalized medicine
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The genetic basis and improvement of photosynthesis in tomato
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作者 Haiqiang Dong Fangman Li +7 位作者 Xiaoxiao Xuan John Kojo Ahiakpa Jinbao Tao Xingyu Zhang Pingfei Ge Yaru Wang Wenxian Gai Yuyang Zhang 《Horticultural Plant Journal》 2025年第1期69-84,共16页
Photosynthesis is one the most important chemical reaction in plants,and it is the ultimate energy source of any living organisms.The light and dark reactions are two essential phases of photosynthesis.Light reaction ... Photosynthesis is one the most important chemical reaction in plants,and it is the ultimate energy source of any living organisms.The light and dark reactions are two essential phases of photosynthesis.Light reaction harvests light energy to synthesize ATP and NADPH through an electron transport chain,and as well as giving out O_(2);dark reaction fixes CO_(2) into six carbon sugars by utilizing NADPH and energy from ATP.Subsequently,plants convert optical energy into chemical energy for maintaining growth and development through absorbing light energy.Here,firstly,we highlighted the biological importance of photosynthesis,and hormones and metabolites,photosynthetic and regulating enzymes,and signaling components that collectively regulate photosynthesis in tomato.Next,we reviewed the advances in tomato photosynthesis,including two aspects of genetic basis and genetic improvement.Numerous genes regulating tomato photosynthesis are gradually uncovered,and the interaction network among those genes remains to be constructed.Finally,the photosynthesis occurring in fruit of tomato and the relationship between photosynthesis in leaf and fruit were discussed.Leaves and fruits are photosynthate sources and sinks of tomato respectively,and interaction between photosynthesis in leaf and fruit exists.Additionally,future perspectives that needs to be addressed on tomato photosynthesis were proposed. 展开更多
关键词 PHOTOSYNTHESIS TOMATO genetics IMPROVEMENT LEAF FRUIT
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Genetic factors that predict response and failure of biologic therapy in inflammatory bowel disease
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作者 Milena Peruhova Daniela Stoyanova +3 位作者 Dimitrina Georgieva Miteva Meglena Kitanova Milko Bozhidarov Mirchev Tsvetelina Velikova 《World Journal of Experimental Medicine》 2025年第1期11-23,共13页
Inflammatory bowel disease(IBD)represents a significant disease burden marked by chronic inflammation and complications that adversely affect patients’quality of life.Effective diagnostic strategies involve clinical ... Inflammatory bowel disease(IBD)represents a significant disease burden marked by chronic inflammation and complications that adversely affect patients’quality of life.Effective diagnostic strategies involve clinical assessments,endoscopic evaluations,imaging studies,and biomarker testing,where early diagnosis is essential for effective management and prevention of long-term complications,highlighting the need for continual advancements in diagnostic methods.The intricate interplay between genetic factors and the outcomes of biological therapy is of critical importance.Unraveling the genetic determinants that influence responses and failures to biological therapy holds significant promise for optimizing treatment strategies for patients with IBD on biologics.Through an indepth examination of current literature,this review article synthesizes critical genetic markers associated with therapeutic efficacy and resistance in IBD.Understanding these genetic actors paves the way for personalized approaches,informing clinicians on predicting,tailoring,and enhancing the effectiveness of biological therapies for improved outcomes in patients with IBD. 展开更多
关键词 Inflammatory bowel disease genetic predictors Inflammatory bowel disease treatment Biologic therapy Biologic therapy response genetic markers in inflammatory bowel disease Inflammatory bowel disease treatment failure PHARMACOGENOMICS Biologic therapy efficacy genetic variability
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The collaborative cross mouse for studying the effect of host genetic background on memory impairments due to obesity and diabetes
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作者 Avia Paz Kareem Midlej +2 位作者 Osayd Zohud Iqbal MLone Fuad A.Iraqi 《Animal Models and Experimental Medicine》 2025年第1期126-141,共16页
Background:Over the past few decades,a threefold increase in obesity and type 2 diabetes(T2D)has placed a heavy burden on the health-care system and society.Previous studies have shown correlations between obesity,T2D... Background:Over the past few decades,a threefold increase in obesity and type 2 diabetes(T2D)has placed a heavy burden on the health-care system and society.Previous studies have shown correlations between obesity,T2D,and neurodegenera-tive diseases,including dementia.It is imperative to further understand the relation-ship between obesity,T2D,and cognitive deficits.Methods:This investigation tested and evaluated the cognitive impact of obesity and T2D induced by high-fat diet(HFD)and the effect of the host genetic background on the severity of cognitive decline caused by obesity and T2D in collaborative cross(CC)mice.The CC mice are a genetically diverse panel derived from eight inbred strains.Results:Our findings demonstrated significant variations in the recorded phenotypes across different CC lines compared to the reference mouse line,C57BL/6J.CC037 line exhibited a substantial increase in body weight on HFD,whereas line CC005 ex-hibited differing responses based on sex.Glucose tolerance tests revealed significant variations,with some lines like CC005 showing a marked increase in area under the curve(AUC)values on HFD.Organ weights,including brain,spleen,liver,and kidney,varied significantly among the lines and sexes in response to HFD.Behavioral tests using the Morris water maze indicated that cognitive performance was differentially affected by diet and genetic background.Conclusions:Our study establishes a foundation for future quantitative trait loci map-ping using CC lines and identifying genes underlying the comorbidity of Alzheimer's disease(AD),caused by obesity and T2D.The genetic components may offer new tools for early prediction and prevention. 展开更多
关键词 collaborative cross mouse DIABETES host genetic background memory impairments OBESITY
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Genetic diversity and population genetic structure of Paeonia suffruticosa by chloroplast DNA simple sequence repeats(cpSSRs)
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作者 Qi Guo Xian Xue +5 位作者 Duoduo Wang Lixia Zhang Wei Liu Erqiang Wang Xiaoqiang Cui Xiaogai Hou 《Horticultural Plant Journal》 2025年第1期367-376,共10页
Paeonia suffruticosa Andr.is an endemic shrub flower in China with 2n=10.This study used 228 cultivars from four populations,i.e.,Jiangnan,Japan,Northwest,and Zhongyuan,as materials to explore the genetic diversity le... Paeonia suffruticosa Andr.is an endemic shrub flower in China with 2n=10.This study used 228 cultivars from four populations,i.e.,Jiangnan,Japan,Northwest,and Zhongyuan,as materials to explore the genetic diversity levels among different populations of tree peony varieties.The results showed that 34 bands were amplified using five pairs of cp SSR primers,with an average of 6.8 bands per primer pair.The average number of different alleles(N_(a)),effective alleles(N_(e)),Shannon's information index(I),diversity(H),and polymorphic information content(PIC)were 3.600,2.053,0.708,0.433,and 0.388,respectively.The PIC value was between 0.250 and 0.500,indicating a moderate level of polymorphism for the five cp SSR primer pairs.The genetic diversity levels of peony cultivars varied among different populations,with the Northwest population showing relatively lower levels(I=0.590,H=0.289,and PIC=0.263).A total of 52 haplotypes were identified in the four examined populations,and the number of haplotypes per population ranged from 11 to 22.Forty-four private haplotypes were detected across populations,and the Northwest population exhibiting the highest count of private haplotypes with 17.The mean number of effective number of haplotypes(N_(eh)),haplotypic richness(R_h),and diversity(H)were 8.351,6.824,and 0.893,respectively.Analysis of molecular variance indicated that genetic variation within tree peony germplasm was greater than that between germplasm resources,and the main variation was found within individuals of peony germplasm.Cluster analysis,principal coordinate analysis,and genetic structure analysis classified tree peonies from different origins into two groups,indicating a certain degree of genetic differentiation among these four tree peony cultivation groups.This study provides a theoretical basis for the exploration,utilization,and conservation of peony germplasm resources,as well as for research on the breeding of excellent varieties. 展开更多
关键词 Paeonia suffruticosa Chloroplast microsatellites(cp SSR) genetic diversity Haplotypes Germplasm resources
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A Preliminary Study on Conservation Genetics of Three Endangered Orchid Species 被引量:16
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作者 李昂 罗毅波 +1 位作者 熊治廷 葛颂 《Acta Botanica Sinica》 CSCD 2002年第2期250-252,共3页
采用随机扩增多态DNA(RAPD)分析研究了中国 3种珍稀濒危兰科植物硬叶兜兰 (PaphiopedilummicranthumTangetWang)、麻栗坡兜兰 (P .malipoenseS .C .ChenetTsi)和独花兰 (ChangnieniaamoenaChien)的遗传多样性与群体遗传结构。 12个RAPD... 采用随机扩增多态DNA(RAPD)分析研究了中国 3种珍稀濒危兰科植物硬叶兜兰 (PaphiopedilummicranthumTangetWang)、麻栗坡兜兰 (P .malipoenseS .C .ChenetTsi)和独花兰 (ChangnieniaamoenaChien)的遗传多样性与群体遗传结构。 12个RAPD引物在 2种兜兰中共扩增出 131条带。对 4个硬叶兜兰群体的检测表明其物种水平的多态条带百分率 (PPB)为 71.6 % ,Nei的基因多样度 (h)为 0 .2 171,Shannon多样性指数 (I)为 0 .330 1;4个群体的平均多样性水平为PPB =45 .2 % ,h =0 .145 7,I =0 .2 2 0 4,低于远交兰花的平均水平。在总遗传变异中 ,群体间遗传变异占 2 0 .31% ,略高于远交物种的平均水平。在物种水平上 ,麻栗坡兜兰的PPB为 49.5 % ,h为 0 .1174,I为0 .176 4,均大大低于硬叶兜兰。对 11个独花兰群体采用 16个RAPD引物共扩增出 119条带。物种水平PPB =76 .5 % ,h =0 .1941,I=0 .30 5 8;在群体水平上 ,上述 3个指标的平均值则分别为 37.2 %、0 .1197和 0 .1810 ,均低于远交兰花的平均水平。群体间的遗传变异占 45 .2 7% ,遗传分化明显高于远交物种的平均水平。导致 3个物种遗传多样性偏低而群体间遗传分化较高的主要原因在于人为的过度采挖和生境的片断化。 展开更多
关键词 PAPHIOPEDILUM Changnienia amoena RAPDS conservation genetics
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A Preliminary Study on Conservation Genetics of Endangered Vatica guangxiensis (Dipterocarpaceae) 被引量:10
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作者 李巧明 许再富 何田华 《Acta Botanica Sinica》 CSCD 2002年第2期246-249,共4页
运用 2 0个 10碱基随机引物 ,对中国龙脑香科 (Dipterocarpaceae)特有的珍稀濒危植物版纳青梅 (VaticaguangxiensisX .L .Mo)进行了RAPD多态性分析。 3个自然居群和 1个迁地保护居群 (分布于云南和广西 )共扩增出2 31个位点 ,多态位点... 运用 2 0个 10碱基随机引物 ,对中国龙脑香科 (Dipterocarpaceae)特有的珍稀濒危植物版纳青梅 (VaticaguangxiensisX .L .Mo)进行了RAPD多态性分析。 3个自然居群和 1个迁地保护居群 (分布于云南和广西 )共扩增出2 31个位点 ,多态位点所占比例 (PPB)为 5 3.6 8% ;观察等位基因数na =1.5 36 8,有效等位基因数ne =1.2 878,Nei基因多样性指数h为 0 .16 86 ,居群内的遗传多样性水平较低。基于AMOVA和POPGENE的结果均表明居群内的遗传变异大于居群间的遗传变异。居群内的遗传变异为 5 5 .0 9% ,居群间的变异为 44 .91% (AMOVA) ;基因分化系数Gst为 0 .3746 (POPGENE) ,表明居群间存在高水平的遗传分化。研究结果对该濒危植物的保护有重要意义。考虑到低水平的遗传多样性和高水平的居群分化 ,通过居群间种子和幼苗的交换来促进基因流是可行的保护方案。迁地保护居群 (ML)不具最高的遗传多样性 ,表明为了保护此濒危物种的全部遗传变异 。 展开更多
关键词 Vatica guangxiensis RAPD genetic diversity conservation biology
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Compound Genetics Annealing Optimal Algorithm for Realization of Locus Deduction of a Plane Link 被引量:1
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作者 林晓通 林晓辉 +1 位作者 黄卫 王宁生 《Journal of Southeast University(English Edition)》 EI CAS 2002年第4期310-314,共5页
A compound algorithm of genetic annealing is designed for optimizing the luffing mechanism locus of a plane link by means of random optimal algorithm, genetic and annealing algorithm. The computing experiment shows th... A compound algorithm of genetic annealing is designed for optimizing the luffing mechanism locus of a plane link by means of random optimal algorithm, genetic and annealing algorithm. The computing experiment shows that the algorithm has much better steady convergence performance of optimal process and can hunt out the global optimal solution by biggish probability for objective function of multi peak value. 展开更多
关键词 genetic annealing algorithm luffing mechanism optimal algorithm
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Study on the Acute Toxicity and Genetics Toxicity of Bensulfuronk-methyl on Danio rerio 被引量:11
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作者 姜罡丞 《Agricultural Science & Technology》 CAS 2009年第4期128-131,共4页
[Objective] The aim was to study the effect of bensulfuron-methyl herbicide on acute toxicity and genetics toxicity of Danio redo. [ Method] Median lethal concentration was calculated by acute toxicity test, and analy... [Objective] The aim was to study the effect of bensulfuron-methyl herbicide on acute toxicity and genetics toxicity of Danio redo. [ Method] Median lethal concentration was calculated by acute toxicity test, and analyzing the herbicide whether existing in potential toxicity to aquatic organisms or not. Based on the study of acute toxicity, genetics toxicity was carried out, by calculating the micronucleus rate to judge bensulfuron-methyl herbicide whether existing in potential toxicity or not. [ Result ] The LD5o (24 h and 48 h) of bensulfuron-methyl herbicide are 0.698 ml/L and 0.637 ml/L respectively, the safe concentration was 0.159 ml/L. The results on the effects of micronucleus (MN) in erythrocytes of Danio redo induced by bensulfuron-methyl at different times and different concentrations showed that the MN rate of control group was 0.010 3%, the highest MN rate of experimental group reached to 0. 372%, it also indicated that bensulfuron-methyl herbicide had genetics toxicity to Danio redo. At the same detection time, there was dose-effect relationship of MN rate in erythrocytes between treatment and control groups with different concentrations. In the same treatment group, the MN rate in erythrocytes reached to peak value at 24 h, and decreased at 48 h and 72 h with the infection time was prolonged. [ Conclusion ] The study provides some basis for scientifically selecting and reasonably using herbicide. 展开更多
关键词 Danio rerio BENSULFURON-METHYL MICRONUCLEUS Acute toxicity genetics toxicity
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国外遗传学教材“Genetics”一书 简评
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作者 刘丽华 《遗传》 CAS CSCD 北大核心 2004年第1期44-44,共1页
遗传学是生命科学中最富于综合性的中心学科之一,也是现代生命科学发展最为迅速的学科之一。以遗传学为基础发展起来的生物技术正处于浩浩荡荡的新发明浪潮的初期,分子遗传学及生物技术发明创造高潮将要持续到21世纪的很长一段时间,... 遗传学是生命科学中最富于综合性的中心学科之一,也是现代生命科学发展最为迅速的学科之一。以遗传学为基础发展起来的生物技术正处于浩浩荡荡的新发明浪潮的初期,分子遗传学及生物技术发明创造高潮将要持续到21世纪的很长一段时间,并将对医疗、农业、环保等产生革命性的影响。 展开更多
关键词 遗传学 教材 genetics 书评
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