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1.
Phys Rev Lett ; 127(6): 069902, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34420355

RESUMO

This corrects the article DOI: 10.1103/PhysRevLett.116.217201.

2.
Epidemiol Infect ; 146(10): 1245-1252, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29781416

RESUMO

Rabies was eliminated from Japan in 1957. In the 60 years since elimination, vaccination coverage has declined and dog ownership habits have changed. The purpose of this study was to assess the current risk of rabies spread in Japan. A spatially explicit transmission model was developed at the 1 km2 grid scale for Hokkaido and Ibaraki Prefectures. Parameters associated with dog movement and bite injuries were estimated using historical records from Japan, and were used with previously published epidemiological parameters. The final epidemic size, efficacy of rabies contingency plans and the influence of dog owner responses to incursions were assessed by the model. Average outbreak sizes for dog rabies were 3.1 and 4.7 dogs in Hokkaido and Ibaraki Prefectures, respectively. Average number of bite injury cases were 4.4 and 6.7 persons in Hokkaido and Ibaraki Prefectures, respectively. Discontinuation of mandatory vaccination increased outbreak sizes in these prefectures. Sensitivity analyses showed that higher chance of unintentional release of rabid dogs by their owners (from 0.5 to 0.9 probability) increased outbreak size twofolds. Our model outputs suggested that at present, incursions of rabies into Japan are very unlikely to cause large outbreaks. Critically, the reaction of dog owners to their dogs developing rabies considerably impacts the course of outbreaks. Contingency measures should therefore include sensitisation of dog owners.


Assuntos
Mordeduras e Picadas/epidemiologia , Surtos de Doenças/veterinária , Doenças do Cão/epidemiologia , Raiva/epidemiologia , Raiva/veterinária , Animais , Doenças do Cão/transmissão , Cães , Humanos , Japão/epidemiologia , Modelos Teóricos , Raiva/prevenção & controle , Raiva/transmissão , Medição de Risco , Fatores de Risco , Análise Espacial , Cobertura Vacinal/estatística & dados numéricos
3.
Phys Rev Lett ; 116(21): 217201, 2016 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-27284670

RESUMO

A hidden order that emerges in the frustrated pyrochlore Tb_{2+x}Ti_{2-x}O_{7+y} with T_{c}=0.53 K is studied using specific heat, magnetization, and neutron scattering experiments on a high-quality single crystal. Semiquantitative analyses based on a pseudospin-1/2 Hamiltonian for ionic non-Kramers magnetic doublets demonstrate that it is an ordered state of electric quadrupole moments. The elusive spin liquid state of the nominal Tb_{2}Ti_{2}O_{7} is most likely a U(1) quantum spin-liquid state.

4.
Rev Sci Tech ; 34(3): 699-712, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27044146

RESUMO

An outbreak of foot and mouth disease occurred in Miyazaki, Japan, in April 2010, and nearly 290,000 animals were culled to control the disease. This study was conducted to demonstrate the causes and intensity of mental distress felt by the field veterinarians participating in the control programme. A focus group discussion was conducted with ten veterinarians to understand their distress during the outbreak, and a questionnaire to quantify the degree of distress experienced each week was administered to 16 veterinarians. A detailed questionnaire was separately administered to 70 veterinarians six months after the outbreak was controlled, to assess mental distress status and to identify the risk factors for serious mental illness (SMI) using the six-item Kessler scale (K6). Overall, mental distress (mean 3.1) was significantly greater than physical distress (mean 1.9, p < 0.001). The risk factors for mental distress were categorised into three groups: culling, communication with farmers, and gender; each category was qualitatively described. Only two respondents (2.9%) had high K6 scores suggesting SMI. In the final generalised linear models with quasi-Poisson errors, the riskfactorsfor SMI that remained were: disinfecting vehicles (p = 0.01), distress (p <0.001), and increased alcohol consumption (p = 0.057), and a protective factor: participation in culling (p = 0.07), which suggested healthy worker bias. Sensitive individuals had been allocated to non-culling activities during disease control. In conclusion, human resource management was adequate during the outbreak from a public-health perspective. However, monitoring delayed symptoms of post-traumatic stress disorder is recommended.


Assuntos
Surtos de Doenças/veterinária , Febre Aftosa/epidemiologia , Estresse Fisiológico , Estresse Psicológico , Médicos Veterinários/psicologia , Adulto , Animais , Eutanásia Animal , Feminino , Humanos , Japão/epidemiologia , Masculino , Transtornos Mentais , Saúde Mental , Pessoa de Meia-Idade , Descanso , Fatores de Risco , Inquéritos e Questionários , Fatores de Tempo
5.
Anim Genet ; 43(6): 721-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22509953

RESUMO

Respiratory disease is the most important health concern for the swine industry. Genetic improvement for disease resistance is challenging because of the difficulty in obtaining good phenotypes related with disease resistance; however, identification of genes or markers associated with disease resistance can help in the genetic improvement of pig health. The purpose of our study was to investigate whether quantitative trait loci (QTL) associated with disease resistance were segregated in a purebred population of Landrace pigs that had been selected for meat production traits and mycoplasmal pneumonia of swine (MPS) scores over five generations. We analysed 1395 pigs from the base to the fifth generation of this population. Two respiratory disease traits [MPS scores and atrophic rhinitis (AR) scores] and 11 immune-capacity traits were measured in 630-1332 animals at 7 weeks of age and when the animal's body weight reached 105 kg. Each of the pigs, except sires in the base population, was genotyped using 109 microsatellite markers, and then, QTL analysis of the full-sib family population with a multi-generational pedigree structure was performed. Variance component analysis was used to detect QTL associated with MPS or AR scores, and the logarithm of odds (LOD) score and genotypic heritability of the QTL were estimated. Five significant (LOD > 2.51) and 18 suggestive (LOD > 1.35) QTL for respiratory disease traits and immune-capacity traits were detected. The significant QTL for Log-MPS score, located on S. scrofa chromosome 2, could explain 87% of the genetic variance of this score in this analysis. This is the first report of QTL associated with respiratory disease lesions.


Assuntos
Resistência à Doença/genética , Pneumonia Suína Micoplasmática/genética , Locos de Características Quantitativas , Doenças Respiratórias/veterinária , Rinite Atrófica/veterinária , Doenças dos Suínos/genética , Animais , Mapeamento Cromossômico , Feminino , Marcadores Genéticos , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Masculino , Carne , Repetições de Microssatélites/genética , Pneumonia Suína Micoplasmática/imunologia , Doenças Respiratórias/genética , Doenças Respiratórias/imunologia , Rinite Atrófica/genética , Rinite Atrófica/imunologia , Suínos , Doenças dos Suínos/imunologia
6.
Anim Genet ; 43(2): 225-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22404360

RESUMO

The stearoyl-CoA desaturase (delta-9-desaturase; SCD) gene is a candidate gene for fatty acid composition. It is located on pig SSC14 in a region where quantitative trait loci (QTL) for fatty acid composition were previously detected in a Duroc purebred population. The objective of the present study was to fine map the QTL, to identify polymorphisms of the pig SCD gene and to examine the effects of SCD polymorphisms on fatty acid composition and melting point of fat in the population. The pigs were examined for fatty acid composition and melting point of inner and outer subcutaneous fat and inter- and intramuscular fat; the number of pigs examined was 479-521. Two SNPs (g.-353C>T and g.-233T>C) were identified in the promoter region of the SCD gene and were completely linked in the pigs from the base generation. In all pigs, 19 microsatellite markers and SCD haplotypes were then genotyped. Different statistical models were applied to evaluate the effects of QTL and the possible causality of the SCD gene variants with respect to the QTL. The results show that all significant QTL for C14:0, C18:0, C18:1 and melting point of fat were detected in the same region, located near the SCD gene. The results also show a significant association between SCD haplotypes and fatty acid composition and fat melting point in this population. These results indicate that the haplotype of the SCD gene has a strong effect on fatty acid composition and melting point of fat.


Assuntos
Tecido Adiposo/metabolismo , Ácidos Graxos/metabolismo , Carne , Locos de Características Quantitativas , Estearoil-CoA Dessaturase/genética , Sus scrofa/genética , Sus scrofa/metabolismo , Animais , Estearoil-CoA Dessaturase/metabolismo
7.
Anim Genet ; 43(1): 27-34, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22221022

RESUMO

The fatty acid composition and melting point of fatty tissue are among the most important economic traits in pig breeding because of their influence on the eating quality of meat. Identifying the quantitative trait locus (QTL) of these traits may help reveal the genetic structure of fatty acid composition and the melting point of fatty tissue and improve meat-quality traits by marker-assisted selection. We conducted whole-genome QTL analysis for fatty acid composition and melting point of inner and outer subcutaneous fat and inter- and intramuscular fat in a purebred Duroc population. A total of 129 markers were genotyped and used for QTL analysis. For fatty acid compositions of inner and outer subcutaneous fat, three significant QTL and 17 suggestive QTL were detected on SSC2, 4, 6, 8, 9, 10, 11, 12, 14 and 18. For the melting point of inner and outer subcutaneous fat, two significant QTL were detected on the same region of SSC14. For fatty acid compositions of inter- and intramuscular fat, five significant QTL and 13 suggestive QTL were detected on SSC2, 4, 6, 8, 9, 10, 14 and 15. On SSC14, significant QTL for C18:0 and C18:1 of outer subcutaneous fat and intramuscular fat, and melting point of subcutaneous fat, which had high likelihood of odds (LOD) scores (2.67-5.78), were detected in the same region. This study determined QTL affecting fatty acid composition and melting point of different fat tissues in purebred Duroc pigs.


Assuntos
Carne , Sus scrofa/genética , Animais , Gorduras na Dieta/análise , Ácidos Graxos/análise , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Gordura Subcutânea/química , Temperatura de Transição
8.
J Anim Sci ; 89(3): 601-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21097684

RESUMO

Most QTL detection studies in pigs have been carried out in experimental F(2) populations. However, segregation of a QTL must be confirmed within a purebred population for successful implementation of marker-assisted selection. Previously, QTL for meat quality and carcass traits were detected on SSC 7 in a Duroc purebred population. The objectives of the present study were to carry out a whole-genome QTL analysis (except for SSC 7) for meat production, meat quality, and carcass traits and to confirm the presence of segregating QTL in a Duroc purebred population. One thousand and four Duroc pigs were studied from base to seventh generation; the pigs comprised 1 closed population of a complex multigenerational pedigree such that all individuals were related. The pigs were evaluated for 6 growth traits, 7 body size traits, 8 carcass traits, 2 physiological traits, and 11 meat quality traits, and the number of pigs with phenotypes ranged from 421 to 953. A total of 119 markers were genotyped and then used for QTL analysis. We utilized a pedigree-based, multipoint variance components approach to test for linkage between QTL and the phenotypic values using a maximum likelihood method; the logarithm of odds score and QTL genotypic heritability were estimated. A total of 42 QTL with suggestive linkages and 3 QTL with significant linkages for 26 traits were detected. These included selection traits such as daily BW gain, backfat thickness, loin eye muscle area, and intramuscular fat content as well as correlated traits such as body size and meat quality traits. The present study disclosed QTL affecting growth, body size, and carcass, physiological, and meat quality traits in a Duroc purebred population.


Assuntos
Mapeamento Cromossômico , Genoma , Locos de Características Quantitativas/genética , Suínos/genética , Suínos/fisiologia , Animais , Composição Corporal/genética , Tamanho Corporal/genética , Genótipo , Carne
9.
J Anim Sci ; 87(7): 2209-15, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19329483

RESUMO

Animals accumulate fat in tissues as subcutaneous, intermuscular, intramuscular, and abdominal fat. Genetic interrelationships of respective fat depositions, however, have not been examined in depth. This study estimated genetic parameters for subcutaneous, intermuscular, and abdominal fat areas of 545 Duroc purebred pigs slaughtered at 105 kg of BW. Measurements were obtained using an image analysis system for positions between the 5th and the 6th thoracic vertebra (56TV), at half body length (HBL), and at the last thoracic vertebra (LTV) of the carcass. Moreover, serum leptin, which is a hormone product that is synthesized and predominantly expressed by adipocytes, was measured to determine if serum concentrations of leptin are useful as physiological predictors of fat accumulation in pigs. The heritability estimate of all fat area percentage at the HBL (0.70 +/- 0.03) was significantly greater than at the 56TV (0.53 +/- 0.03) or the LTV (0.55 +/- 0.04). Furthermore, the heritability estimate of subcutaneous fat areas at the HBL (0.71 +/- 0.04) was greater than at the 56TV (0.56 +/- 0.04) or LTV (0.60 +/- 0.03). Moreover, high heritabilities were estimated for ultrasound backfat thickness (BF; 0.72 +/- 0.03) on the left side at the position of HBL, intramuscular fat content of the loin (0.51 +/- 0.03), the seam fat score (SFS; 0.49 +/- 0.04), and the serum leptin concentration (0.62 +/- 0.05). Increased genetic correlations of BF with the fat area percentage of subcutaneous fat and all fat at 56TV (0.90 +/- 0.03 and 0.91 +/- 0.03), at HBL (0.88 +/- 0.03 and 0.94 +/- 0.01), and at LTV (0.88 +/- 0.03 and 0.90 +/- 0.02) were estimated. The genetic correlations of serum leptin concentration with the percentage of subcutaneous fat area and all fat areas at each position were also high (0.72 to 0.82 and 0.83 to 0.84, respectively). These results suggest that BF and leptin are good indicators of selection for decreasing fat deposition. Increased genetic correlation of the SFS with intermuscular fat area at 56TV (0.74) suggests that SFS is an effective indicator for decreasing intermuscular fat. The genetic correlation between the leptin concentration and feed conversion ratio was high (0.75 +/- 0.04). Results of this study indicate that the combination of BF and serum leptin concentration is a valuable indicator that can be incorporated into selection programs to improve carcass quality and feed efficiency in pigs.


Assuntos
Tecido Adiposo/fisiologia , Composição Corporal/genética , Leptina/sangue , Músculo Esquelético/fisiologia , Suínos/genética , Animais , Cruzamento , Suínos/sangue , Suínos/fisiologia
10.
J Anim Breed Genet ; 124(3): 108-16, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17550351

RESUMO

Genetic parameters for feed efficiency traits of 380 boars and growth and carcass traits of 1642 pigs (380 boars, 868 gilts and 394 barrows) in seven generations of Duroc population were estimated. Feed efficiency traits included the feed conversion ratio (FCR), and nutritional (RFI(nut)), phenotypic (RFI(phe)) and genetic (RFI(gen)) residual feed intake. Growth and carcass traits were the age to reach 105-kg body weight (A105), loin eye muscle area (EMA), backfat (BF), intra-muscular fat (IMF) and meat tenderness. The mean values for RFI(phe) and RFI(gen) were close to zero and for RFI(nut) was negative. All the measures of feed efficiency were moderately heritable (h(2) = 0.31, 0.38, 0.40 and 0.27 for RFI(nut), RFI(phe), RFI(gen) and FCR respectively). The heritabilities for all growth and carcass traits were moderate (ranged from 0.37 to 0.45), except for BF, which was high (0.72). The genetic correlations of RFI(phe) and RFI(gen) with A105 were positive and high. Measures of RFI were correlated negatively with EMA. BF was more strongly correlated with measures of RFI (r(g) > or = 0.73) than with FCR (r(g) = 0.52). Selection for daily gain, EMA, BF and IMF caused favourable genetic changes in feed efficiency traits. Results of this study indicate that selection against either RFI(phe) or RFI(gen) would give a similar correlated response in carcass traits.


Assuntos
Ração Animal , Composição Corporal/genética , Suínos/crescimento & desenvolvimento , Suínos/genética , Aumento de Peso/genética , Animais , Feminino , Variação Genética , Masculino , Suínos/anatomia & histologia
11.
J Anim Sci ; 85(8): 1873-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17431052

RESUMO

Genetic parameters for the efficiency of gain traits on 380 boars and the genetic relationships with component traits were estimated in 1,642 pigs (380 boars, 868 gilts, and 394 barrows) in 7 generations of a Duroc population. The efficiency of gain traits included the feed conversion ratio (FCR) and residual feed intake (RFI) and their component traits, ADG, metabolic BW (MWT), and daily feed intake (FI). The RFI was calculated as the difference between the actual and expected FI. The expected FI was predicted by the nutritional requirement and by the residual of phenotypic (RFI(phe)) and genetic (RFI(gen)) regressions from the multivariate analysis for FI on MWT and ADG. The means for RFI(phe) and RFI(gen) were close to zero, and the mean for nutritional RFI was negative (-0.11 kg/d). The traits studied were moderately heritable (ranging from 0.27 to 0.53). The genetic and phenotypic correlations between ADG and FI were moderate to high, whereas the genetic correlation between MWT and FI was moderate, and the phenotypic correlation between them was low. The corresponding correlations between RFI(phe) and RFI(gen) were > 0.95, implying that they can be regarded as the same trait. The genetic and phenotypic correlations of FCR with measures of RFI were high but lower than unity. The RFI(phe) was phenotypically independent of its component traits, MWT (r(p) = 0.01) and ADG (r(p) = 0.03). The RFI(gen) was genetically independent of MWT (r(g) = -0.04), whereas there was a weak genetic relationship (r(g) = 0.15) between RFI(gen) and ADG. Residual FI was more heritable than FCR, and the genetic and phenotypic correlations of RFI(phe) and RFI(gen) with FI were positive and stronger than that of FCR with FI. These results provide evidence that RFI(phe) or RFI(gen) should be included in breeding programs for Duroc pigs to make genetic improvement in the efficiency of gain.


Assuntos
Suínos/crescimento & desenvolvimento , Suínos/genética , Aumento de Peso/genética , Animais , Ingestão de Alimentos/genética , Feminino , Variação Genética , Masculino , Fenótipo
12.
J Anim Sci ; 84(8): 2026-34, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16864861

RESUMO

This study estimated genetic parameters for fatty acids of different sites of fat tissue, meat production, and meat quality traits of Duroc pigs selected during 7 generations for ADG, LM area, backfat thickness (BF), and intramuscular fat (IMF). For this study, 394 barrows and 153 gilts were slaughtered at 105 kg of BW. High heritabilities for C18:0 of outer and inner subcutaneous fat tissue were estimated, respectively, as 0.54 and 0.51; those of intermuscular and intramuscular fat were 0.40 and 0.51, respectively. Genetic and phenotypic correlations of ADG and BF with saturated fatty acids of outer and inner subcutaneous fat were positive, but those with C16:1 and C18:2 were negative, and those with C18:1 were nearly zero. Genetic and phenotypic correlations between LM area and respective fatty acids showed opposite results. Respective genetic and phenotypic correlations of melting points with C18:0 and C18:1 were positive and high, and negative and high, respectively. Genetic correlations between cooking loss and SFA (C14:0, C16:0, and C18:0) of IMF were positive and moderate: 0.56, 0.47, and 0.47, respectively. On the other hand, monosaturated fatty acid of C18:1 was highly and negatively correlated with cooking loss (-0.61). Moreover, high genetic correlation between meat color (pork color standard and lightness) and fatty acid compositions of IMF suggest that the SFA (C14:0, C16:0, and C18:0) were correlated genetically with meat lightness and that unsaturated fatty acid compositions (C18:1 and C18:2) were correlated with meat darkness. Results of this study suggest that the fatty acid composition of adipose tissue is correlated genetically with meat production and meat quality traits.


Assuntos
Tecido Adiposo/metabolismo , Composição Corporal/genética , Ácidos Graxos/genética , Ácidos Graxos/metabolismo , Carne/normas , Suínos/genética , Animais , Peso Corporal/genética , Feminino , Genótipo , Masculino , Fenótipo , Seleção Genética
13.
Phys Rev Lett ; 97(25): 257205, 2006 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-17280389

RESUMO

We have investigated the kagomé ice behavior of the dipolar spin-ice compound Dy2Ti2O7 in a magnetic field along a [111] direction using neutron scattering and Monte Carlo simulations. The spin correlations show that the kagomé ice behavior predicted for the nearest-neighbor interacting model, where the field induces dimensional reduction and spins are frustrated in each two-dimensional kagomé lattice, occurs in the dipole interacting system. The spins freeze at low temperatures within the macroscopically degenerate ground states of the nearest-neighbor model.

14.
J Anim Sci ; 83(9): 2058-65, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16100060

RESUMO

Using a multitrait animal model BLUP, selection was conducted over seven generations for growth rate (ADG), real-time ultrasound LM area (LMA), backfat thickness (BF), and intramuscular fat content (IMF) to develop a new line of purebred Duroc pigs with enhanced meat production and meat quality. This selection experiment examined 543 slaughtered pigs (394 barrows and 153 gilts) from the first to the seventh generation for meat quality traits. Further, electric impedance and collagen content of loin meat were measured from the fourth to sixth generation. The present study was intended to estimate genetic parameters of the correlated traits of tenderness (TEND), meat color (pork color standard: PCS; lightness = L*), drip loss (DL), cooking loss (CL), pH (PH), electric impedance (IMP), and collagen (COL) of the LM, and the genetic trends of these traits. Respective heritability estimates for IMF, TEND, DL, CL, PCS, L*, PH, IMP, and COL were 0.39, 0.45, 0.14, 0.09, 0.18, 0.16, 0.07, 0.22, and 0.23. Genetic correlations of IMF with ADG and BF were low and positive, but low and negative with LMA. Tenderness was correlated negatively with ADG (-0.44) and BF (-0.59), but positively correlated with LMA (0.32). The genetic correlation between LMA and DL was positive and high (0.64). The genetic correlations of TEND with IMF and COL were low (-0.09 and 0.26, respectively), but a moderate genetic correlation (0.43) between COL and IMF was estimated, suggesting related increases of IMF and connective tissue. Genetic correlations among meat quality traits suggested that when IMF increases, the water holding capacity improves. Genetic trends of meat quality traits showed increased IMF and lighter meat color.


Assuntos
Cruzamento , Carne/normas , Modelos Genéticos , Suínos/genética , Tecido Adiposo/fisiologia , Animais , Colágeno/análise , Impedância Elétrica , Meio Ambiente , Feminino , Masculino , Músculo Esquelético/fisiologia , Fenótipo , Seleção Genética , Suínos/fisiologia , Aumento de Peso/genética , Aumento de Peso/fisiologia
15.
J Phys Chem B ; 109(48): 22995-3000, 2005 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-16853996

RESUMO

The ruthenium oxide-loaded composite p-block metal oxide LiInGeO4 with d10-d10 configuration exhibited high photocatalytic activity for the overall splitting of water to produce H2 and O2 under UV irradiation. Changes in the photocatalytic activity with the calcination temperature of LiInGeO4, the amount of RuO2 loaded, and the states of RuO2 indicated that the combination of highly crystallized LiInGeO4 and a high dispersion of RuO2 particles resulted in high photocatalytic activity. Structurally, LiInGeO4 contained heavily distorted InO6 octahedra and GeO4 tetrahedra, generating a dipole moment inside. The high photocatalytic performance of RuO2-loaded LiInGeO4 supports the existing view that the photocatalytic activity correlates with the dipole moment. The DFT calculation showed that the top of the valence band (HOMO) was composed of the O 2p orbital while the bottom of the conduction band (LUMO) was formed by the hybridized In 5s5p + Ge 4s4p + O 2p orbitals. The highly dispersed conduction band, indicative of a high mobility of photoexcited electrons, was responsible for the high photocatalytic performance.

16.
Cell Death Differ ; 12(1): 19-24, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15592360

RESUMO

Amyloid beta (Abeta) is a main component of senile plaques in Alzheimer's disease and induces neuronal cell death. Reactive oxygen species (ROS), nitric oxide and endoplasmic reticulum (ER) stress have been implicated in Abeta-induced neurotoxicity. We have reported that apoptosis signal-regulating kinase 1 (ASK1) is required for ROS- and ER stress-induced JNK activation and apoptosis. Here we show the involvement of ASK1 in Abeta-induced neuronal cell death. Abeta activated ASK1 mainly through production of ROS but not through ER stress in cultured neuronal cells. Importantly, ASK1-/- neurons were defective in Abeta-induced JNK activation and cell death. These results indicate that ROS-mediated ASK1 activation is a key mechanism for Abeta-induced neurotoxicity, which plays a central role in Alzheimer's disease.


Assuntos
Peptídeos beta-Amiloides/farmacologia , MAP Quinase Quinase Quinase 5/metabolismo , Neurônios/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Doença de Alzheimer/etiologia , Animais , Morte Celular/efeitos dos fármacos , Retículo Endoplasmático/enzimologia , Retículo Endoplasmático/metabolismo , Ativação Enzimática/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , MAP Quinase Quinase Quinase 5/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/citologia , Neurônios/metabolismo , Óxidos de Nitrogênio/metabolismo , Células PC12 , Fragmentos de Peptídeos/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , eIF-2 Quinase/metabolismo
17.
J Anim Sci ; 82(4): 994-9, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15080319

RESUMO

This study was intended to examine whether serum IGF-I concentration is appropriate for use as a physiological predictor for genetic improvement of meat production and meat quality traits in pigs. Heritabilities and genetic correlations were estimated for these traits. The Duroc breed used in this study was selected for seven generations for average daily BW gain (DG) from 30 to 105 kg of BW, loin-eye muscle area (EM), backfat thickness (BF), and intramuscular fat (IMF) content. Serum IGF-I concentration of boars and gilts at the fourth generation of selection and that of boars, gilts, and barrows from the fifth to seventh generations of selection were measured at 8 wk (IGFI-8W) for 832 animals and again at the time they reached 105 kg of BW (IGFI-105KG) for 834 animals. A multivariate REML procedure was used to estimate genetic parameters with a model incorporating generation of selection, sex, common environmental effect of litter, and individual additive genetic effects. Heritability estimates for IGFI-8W and IGFI-105KG were 0.23 +/- 0.02 and 0.26 +/- 0.03, respectively. The estimates of common environmental effect for IGFI-8W and IGFI-105KG were 0.20 +/- 0.02 and 0.03 +/- 0.01, respectively. Positive genetic correlations were estimated between IGFI-8W and DG (0.26 +/- 0.08), EM (0.22 +/- 0.10), and IMF (0.32 +/- 0.10). Moreover, the positive genetic correlation between IGFI-105KG and EM was 0.42 +/- 0.08. These results indicate that serum IGF-I concentration at an early stage of growth was effective for prediction of IMF, but it was not a reliable physiological predictor of genetic merit of meat production traits.


Assuntos
Cruzamento/métodos , Fator de Crescimento Insulin-Like I/análise , Carne/normas , Suínos/genética , Aumento de Peso/genética , Tecido Adiposo/metabolismo , Animais , Biomarcadores/sangue , Composição Corporal/genética , Feminino , Fator de Crescimento Insulin-Like I/genética , Masculino , Modelos Genéticos , Análise Multivariada , Seleção Genética , Suínos/sangue , Suínos/fisiologia
18.
Meat Sci ; 64(1): 35-42, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-22062660

RESUMO

The object of this study is to specify features determining meat quality of Berkshire and Duroc and influence of these purebreds on meat quality of crossbred pigs. In total, 37 purebred pigs (Berkshire and Duroc: originating from line breeding in Kagoshima Prefecture and Miyagi Prefecture, respectively) and two crossbreeds (LDB and LDD: produced by crossing Berkshire and Duroc boars to Duroc-Landrace sows) were used. Berkshire accumulated more subcutaneous and abdominal fat and had small loin eye muscle area, but accumulated less intramuscular fat than Duroc. There were no differences in meat colour and tenderness between the two purebreds. But Berkshire was less than Duroc in drip loss. As for fatty acid of inner and outer subcutaneous fat, Berkshire contained significantly higher concentration of saturated fatty acids, but had lower concentration of unsaturated fatty acid than Duroc. As a result, the melting point of inner and outer subcutaneous fat and perirenal fat of Berkshire was significantly higher than that of Duroc. Furthermore, though there was no breed difference in concentration of saturated fatty acids of intramuscular fat, Duroc had more oleic acid (C18:1) than Berkshire. Fatty acid concentrations of inner and outer subcutaneous fat and intramuscular fat as well as melting points of both subcutaneous fat layers and perirenal fat were the same in Berkshire and LDB and in Duroc and LDD. These results suggest that there were remarkable differences between Berkshire and Duroc in fat quality traits; also, both breeds as terminal sires influenced crossbred pigs' fat accumulation and fat quality traits.

19.
Diabetologia ; 45(5): 740-3, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12107756

RESUMO

AIMS/HYPOTHESIS: Peroxisome proliferator activated receptor gamma coactivator-1 (PGC-1), a transcriptional coactivator of the nuclear receptor PPARgamma, plays a role in adaptive thermogenesis and insulin sensitivity. Plasma fasting insulin has been linked to the chromosomal region where the PGC-1 gene is located. Thus, PGC-1 can be viewed as a functional and positional candidate for the susceptibility gene for Type II (non-insulin-dependent) diabetes mellitus. METHODS: After screening the PGC-1 gene for single nucleotide polymorphisms (SNPs), we performed an association study using the newly detected SNPs in 537 Type II diabetic patients and 417 non-diabetic subjects. RESULTS: We found three relatively frequent SNPs in the PGC-1 gene (IVS4-11T > C, Thr394Thr and Gly482Ser). There were significant differences in fasting insulin (Gly/Gly; 37.7 +/- 1.43, Gly/Ser; 40.2 +/- 1.21, Ser/Ser; 44.3 +/- 1.82 pmol/l, p = 0.018) and insulin resistance index (Gly/Gly; 1.48 +/- 0.06, Gly/Ser; 1.56 +/- 0.05, Ser/Ser; 1.75 +/- 0.08, p = 0.027) according to the genotype of the Gly482Ser polymorphism. The Thr394Thr - Gly482Ser haplotype was associated with Type II diabetes (p = 0.00003). CONCLUSION/INTERPRETATION. The results of this study suggested that the PGC-1 gene might be implicated in the pathogenesis of Type II diabetes.


Assuntos
Diabetes Mellitus Tipo 2/genética , Variação Genética , Proteínas de Choque Térmico/genética , Resistência à Insulina/genética , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/genética , Sequência de Bases , Primers do DNA , Predisposição Genética para Doença , Hemoglobinas Glicadas/análise , Haplótipos , Humanos , Japão , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Valores de Referência , População Branca
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