• Title/Summary/Keyword: Genetic Responses

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Genetic Evaluation and Selection Response of Birth Weight and Weaning Weight in Indigenous Sabi Sheep

  • Assan, N.;Makuza, S.;Mhlanga, F.;Mabuku, O.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.12
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    • pp.1690-1694
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    • 2002
  • Genetic parameters were estimated for birth weight and weaning weight from three year (1991-1993) data totalling 1100 records of 25 rams to 205 ewes of Indigenous Sabi flock maintained at Grasslands Research Station in Zimbabwe. AIREML procedures were used fitting an Animal Model. The statistical model included the fixed effects of year of lambing, sex of lamb, birth type and the random effect of ewe. Weight of ewe when first joined with ram was included as a covariate. Direct heritability estimates of 0.27 and 0.38, and maternal heritability estimates of 0.24 and 0.09, were obtained for birth weight and weaning weight, respectively. The total heritability estimates were 0.69 and 0.77 for birth weight and weaning weight, respectively. Direct-aternal genetic correlations were high and positive. The corresponding genetic covariance estimates between direct and maternal effects were positive and low, 0.25 and 0.18 for birth weight and weaning weight, respectively. Responses to selection were 0.8 kg and 0.14 kg for birth weight and weaning weight, respectively. The estimated expected correlated response to selection for birth weight by directly selecting for weaning weight was 0.26. Direct heritabilities were moderate; as a result selection for any of these traits should be successful. Maternal heritabilities were low for weaning weight and should have less effect on selection response. Indirect selection can give lower response than direct selection.

The Genetics and Pathogenesis of Inflammatory Bowel Disease (염증성 장질환의 유전학과 병인론)

  • Ko, Jae Sung
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.11 no.sup2
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    • pp.59-66
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    • 2008
  • Genome-wide association studies using large case-control samples and several hundred thousand genetic markers efficiently and powerfully assay common genetic variations. The application of these studies to inflammatory bowel disease has led to the identification of susceptibility genes and affirmed the importance of innate and adaptive immunity in the pathogenesis of disease. Efforts directed towards the identification of environmental factors have implicated commensal bacteria as determinants of dysregulated immunity and inflammatory bowel disease. Host genetic polymorphisms most likely interact with functional bacterial changes to stimulate aggressive immune responses that lead to chronic tissue injury.

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Epigenetic biomarkers: a step forward for understanding periodontitis

  • Lindroth, Anders M.;Park, Yoon Jung
    • Journal of Periodontal and Implant Science
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    • v.43 no.3
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    • pp.111-120
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    • 2013
  • Periodontitis is a common oral disease that is characterized by infection and inflammation of the tooth supporting tissues. While its incidence is highly associated with outgrowth of the pathogenic microbiome, some patients show signs of predisposition and quickly fall into recurrence after treatment. Recent research using genetic associations of candidates as well as genome-wide analysis highlights that variations in genes related to the inflammatory response are associated with an increased risk of periodontitis. Intriguingly, some of the genes are regulated by epigenetic modifications, supposedly established and reprogrammed in response to environmental stimuli. In addition, the treatment with epigenetic drugs improves treatment of periodontitis in a mouse model. In this review, we highlight some of the recent progress identifying genetic factors associated with periodontitis and point to promising approaches in epigenetic research that may contribute to the understanding of molecular mechanisms involving different responses in individuals and the early detection of predispositions that may guide in future oral treatment and disease prevention.

Prophylactic and Therapeutic Applications of Genetic Materials Carrying Viral Apoptotic Function

  • Yang Joo-Sung
    • Proceedings of the Microbiological Society of Korea Conference
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    • 2002.10a
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    • pp.118-120
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    • 2002
  • Genetic materials including DNA plasmid are effective delivery vehicle to express interesting gene efficiently and safely not to generate replication competent virus. Moreover, it has advantages to design a better vector and to simplify manufacturing and storage condition. To understand a possible pathogenic mechanism by a flavivirus, West Nile virus (WNV), WNV genome sequence was aligned to other pathogenic viral genome. Interestingly, WNV capsid (Cp) amino acid sequence has some homology to HIV-l Vpr protein. These proteins induce apoptosis in human cell lines as well as in vivo and cell cycle arrest. Therefore, DNA plasmid carrying apoptosis-inducing and cell cycle arresting viral proteins including a HIV-1 Vpr and a WNV Cp protein can be useful for anti-cancer therapeutic applications. This WNV Cp protein is an early expressed protein which can be a reasonable target antigen (Ag) for vaccine design. Immunization of a DNA construct encoding WNV Cp protein induces a strong Ag-specific humoral and Th1-type immune responses in animal. Therefore, DNA plasmid encoding apoptotic viral proteins can be useful tool for therapeutic and prophylactic applications.

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Tuning of Fuzzy Logic Current Controller for HVDC Using Genetic Algorithm (유전알고리즘을 사용한 HVDC용 퍼지 제어기의 설계)

  • Jong-Bo Ahn;Gi-Hyun Hwang;June Ho Park
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.52 no.1
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    • pp.36-43
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    • 2003
  • This paper presents an optimal tuning method for Fuzzy Logic Controller (FLC) of current controller for HVDC using Genetic Algorithm(GA). GA is probabilistic search method based on genetics and evolution theory. The scaling factors of FLC are tuned by using real-time GA. The proposed tuning method is applied to the scaled-down HVDC simulator at Korea Electrotechnology Research Institute(KERI). Experimental result shows that disturbances are well-damped and the dynamic performances of FLC have the better responses than those of PI controller for small and large disturbances such as ULTC tap change, reference DC current change and DC ground fault.

Control systems design based on the principle of matching with the genetic algorithm incorporating Lamarkism

  • Komatsu, Ken-Ichirou;Ishihara, Tadashi;Inooka, Hikaru;Satoh, Toshiyuki
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.87.3-87
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    • 2001
  • The principle of matching is a new framework for control systems design that requires the matching between the control system and the environment (the source of exogenous inputs). The principle is especially useful for the design of the critical control systems where the responses of the control systems should be kept below the prescribed values. The design problem is reduced to find controller satisfying inequality constraints. However, conventional optimization techniques do not possess structural model selection ability and designers are required to select appropriate controller model. We propose to use a genetic algorithm to find an appropriate controller satisfying the matching conditions. The proposed genetic algorithm ...

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NDRG3-mediated lactate signaling in hypoxia

  • Park, Kyung Chan;Lee, Dong Chul;Yeom, Young Il
    • BMB Reports
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    • v.48 no.6
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    • pp.301-302
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    • 2015
  • Hypoxia is associated with many pathological conditions as well as the normal physiology of metazoans. We identified a lactate-dependent signaling pathway in hypoxia, mediated by the oxygen- and lactate-regulated protein NDRG family member 3 (NDRG3). Oxygen negatively regulates NDRG3 expression at the protein level via the PHD2/VHL system, whereas lactate, produced in excess under prolonged hypoxia, blocks its proteasomal degradation by binding to NDRG3. We also found that the stabilized NDRG3 protein promotes angiogenesis and cell growth under hypoxia by activating the Raf-ERK pathway. Inhibiting cellular lactate production abolishes NDRG3-mediated hypoxia responses. The NDRG3-Raf-ERK axis therefore provides the genetic basis for lactate-induced hypoxia signaling, which can be exploited for the development of therapies targeting hypoxia-induced diseases in addition to advancing our understanding of the normal physiology of hypoxia responses. [BMB Reports 2015; 48(6): 301-302]

Comparison of Genetic Responses Using Reproductive Techniques of MOET and In Vitro Fertilization in Cattle Populations (다배란과 수정란이식 및 체외수정기술을 이용한 소의 유전적 개량량 비교)

  • 전광주
    • Journal of Embryo Transfer
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    • v.11 no.1
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    • pp.1-6
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    • 1996
  • 다배란 수정란이식(MOET)과 체외수정(IVF)기술을 이용한 육종체계에서 예상되는 유전적 개량량을 여러 집단의 크기에서 비교한 결과 체외수정기술이 MOET육종기술보다 특히 개량대상 유전력이 낮을때 훨씬 효율적으로 나타났다. 그러나 유전력이 높아지면 (h$^2$=0.3, 0.5), MOET와 IVF간의 상대적 차이는 미진하게 나타났다. 체외수정을 이용한 육종기술에서 암컷의 선발 강도는 대단히 높일 수 있는 반면 난자의 회수율이 많을수록 상대적으로 수컷에 대한 선발 강도는 낮아진다. 그 이유는 한 가계에서 근친을 피하기 위해 한 마리의 수컷만 선발해야 하므로 수소의 선발강도는 난자의 회수율이 높을수록 상대적으로 낮아진다. 여러 수준의 난자회수율(10, 20, 30, 50, 100)중에서 30일 때 가장 높은 유전적 개량을 나타내었다. (Key word: MOET, IVF,selection responses)

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Semi-active structural fuzzy control with MR dampers subjected to near-fault ground motions having forward directivity and fling step

  • Ghaffarzadeh, Hosein
    • Smart Structures and Systems
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    • v.12 no.6
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    • pp.595-617
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    • 2013
  • Semi-active control equipments are used to effectually enhance the seismic behavior of structures. Magneto-rheological (MR) dampers are semi-active devices that can be utilized to control the response of structures during seismic loads and have received voracious attention for response suppression. They supply the adaptability of active devices and stability and reliability of passive devices. This paper presents an optimal fuzzy logic control scheme for vibration mitigation of buildings using magneto-rheological dampers subjected to near-fault ground motions. Near-fault features including a directivity pulse in the fault-normal direction and a fling step in the fault-parallel direction are considered in the requisite ground motion records. The membership functions and fuzzy rules of fuzzy controller were optimized by genetic algorithm (GA). Numerical study is performed to analyze the influences of near-fault ground motions on a building that is equipped with MR dampers. Considering the uncontrolled system response as the base line, the proposed method is scrutinized by analogy with that of a conventional maximum dissipation energy (MED) controller to accentuate the effectiveness of the fuzzy logic algorithm. Results reveal that the fuzzy logic controllers can efficiently improve the structural responses and MR dampers are quite promising for reducing seismic responses during near-fault earthquakes.