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1.
Animal ; 15(2): 100115, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33712210

RESUMO

On-farm practices like premature weaning and frequent regrouping induce stress to pigs. Early socialization or environmental enrichment in piglets reduce weaning stress, as suggested in previous studies. Little research with both effects and in commercial settings was found. The aim was to investigate the effects of preweaning socialization and environmental enrichment on life-long performance in 661 Danbred pigs. Two treatments were distinguished during the suckling period: control (CON, 24 litters) and enriched (ENR, 24 litters). Control piglets were raised in barren farrowing pens; ENR piglets were provided with six enrichment objects from birth, and two neighboring litters were socialized from Day (D) 14. Pigs were regrouped on D25 (weaning) and D71 (fattening), while keeping the same treatment. Individual body weight was recorded on D1, 14, 23, 27, 31, 38, 69, 79, and after slaughter (carcass weight, CW). Pigs were slaughtered in six batches. Estimated slaughter weight (ESW) was calculated by CW × 1.25. Body weight, CW, and average daily gain (ADG) were analyzed by linear mixed models. Slaughter age was analyzed by Wilcox Rank-Sum test. Body weight and ESW were adjusted to non-linear models to obtain the predicted growth curves of CON and ENR, from birth to the targeted market weight (TMW, 105 kg). Average daily gain during the suckling, nursery, and fattening periods, and from birth to slaughter, did not differ between treatments. However, ADG of ENR when moving pigs from farrowing to nursery (4-day period) and from nursery to fattening (10-day period), revealed a better performance than CON (+20.6 g/day, P = 0.02; +53 g/day, P = 0.03, respectively). Enriched pigs tended to be slaughtered 2.8 days earlier than CON (P = 0.08). On the other hand, the predicted growth curves showed a non-significant 2-day window of reaching TMW between treatments (P = 0.23). Results suggested that enriching the neonatal environment improved the short-term performance after regrouping, and may benefit the life-long performance by reducing time to reach TMW.


Assuntos
Socialização , Animais , Suínos , Desmame
2.
Anim Genet ; 51(2): 292-299, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31887783

RESUMO

Dehong humped cattle (DHH) is an indigenous zebu breed from southwestern China that possesses characteristics of heat tolerance and strong disease resistance and adapts well to the local tropical and subtropical climatic conditions. However, information on selection signatures of DHH is scarce. Herein, we compared the genomes of DHH and each of Diqing and Zhaotong cattle breeds using the population differentiation index (FST ), cross-population extended haplotype homozygosity (XP-EHH) and cross-population composite likelihood ratio (XP-CLR) methods to explore the genomic signatures of heat tolerance and disease resistance in DHH. Several pathways and genes carried selection signatures, including thermal sweating (calcium signaling pathway), heat shock (HSF1) and oxidative stress response (PLCB1, PLCB4), coat color (RAB31), feed intake (ATP8A1, SHC3) and reproduction (TP63, MAP3K13, PTPN4, PPP3CC, ADAMTSL1, SS18L1, OSBPL2, TOX, RREB1, GRK2). These identified pathways and genes may contribute to heat tolerance in DHH. Simultaneously, we also identified LIPH, TP63 and CBFA2T3 genes under positive selection that were associated with immunity.


Assuntos
Bovinos/fisiologia , Resistência à Doença/genética , Estudo de Associação Genômica Ampla/veterinária , Polimorfismo de Nucleotídeo Único , Seleção Genética , Termotolerância/genética , Animais , Cruzamento , Bovinos/genética , China
3.
J Fish Biol ; 93(6): 1082-1089, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30260011

RESUMO

Autotetraploid fish (4n = 200, abbreviated as 4nRR), which reach sexual maturity at 1 year of age, were derived from the whole genome duplication of red crucian carp Carassius auratus red var. (RCC; 2n = 100) and possess four sets of chromosomes from RCC. The histological features of the gonads showed that the RCC and 4nRR both possessed normal gonadal structure and could arrive at maturation. To understand the expression characteristics of genes related to reproductive development in the autotetraploid fish, we analysed the nucleotide sequence and expression characteristics of the gnrh2, gthb and gthr genes, which are the pivotal genes of the hypothalamic-pituitary-gonadal (HPG) axis. We found that the gnrh2, gthb and gthr genes in 4nRR share remarkable homology with RCC, but there were obvious differences in expression levels between 4nRR and RCC. These results demonstrate that autotetraploidization can lead to gene expression changes. This study provides insights into the molecular mechanism underlying the reproductive development of autotetraploid fish and is expected to be of great significance for subsequent research on polyploidization.


Assuntos
Expressão Gênica , Carpa Dourada/genética , Reprodução , Animais , Duplicação Cromossômica , Regulação da Expressão Gênica no Desenvolvimento , Carpa Dourada/anatomia & histologia , Carpa Dourada/fisiologia , Gônadas/anatomia & histologia , Gônadas/metabolismo , Gônadas/fisiologia , Sistema Hipotálamo-Hipofisário , Maturidade Sexual/genética , Tetraploidia
4.
Angew Chem Int Ed Engl ; 56(27): 7740-7744, 2017 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-28471069

RESUMO

Criegee intermediates have implications as key intermediates in atmospheric, organic, and enzymatic reactions. However, their chemistry in aqueous environments is relatively unexplored. Herein, Born-Oppenheimer molecular dynamics (BOMD) simulations examine the dynamic behavior of syn- and anti-CH3 CHOO at the air-water interface. They show that unlike the simplest Criegee intermediate (CH2 OO), both syn- and anti-CH3 CHOO remain inert towards reaction with water. The unexpected high stability of C2 Criegee intermediates is due to the presence of a hydrophobic methyl substituent on the Criegee carbon that lowers the proton transfer ability and inhibits the formation of a pre-reaction complex for the Criegee-water reaction. The simulation of the larger Criegee intermediates, (CH3 )2 COO, syn- and anti-CH2 C(CH3 )C(H)OO on the water droplet surface suggests that strongly hydrophobic substituents determine the reactivity of Criegee intermediates at the air-water interface.

5.
Transpl Infect Dis ; 16(5): 751-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25040633

RESUMO

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (alloHSCT) recipients are at high risk of invasive pneumococcal disease (IPD). We investigated the incidence and risk factors of IPD in alloHSCT recipients from 4 regional transplant centers over an 11-year period. This study aimed to inform future improvements in post-transplant care. METHODS: We conducted a retrospective nested 1:2 case-control study in patients aged ≥18 years who underwent alloHSCT between 2001 and 2011 in 4 major allogeneic transplant centers. Controls were matched with IPD cases on the basis of conditioning intensity and donor relationship (related or unrelated). Demographics and clinical characteristics of cases and controls were summarized. Univariate analysis of risk factors in matched case-control sets, and multivariate conditional logistic regression to control for confounding, were performed. RESULTS: In 23 alloHSCT recipients, 26 IPD episodes were identified. The cumulative incidence over 11 years was 2.3% (95% confidence interval [CI] 1.45-3.15) and the incidence density 956 per 100,000 transplant years of follow-up (95% CI 580-1321). Multivariate risk factor analysis and backwards elimination showed a significant positive association between mycophenolate mofetil (MMF), hyposplenism/asplenia, and IPD, whereas trimethoprim-sulfamethoxazole (TMP/SMX) prophylaxis for Pneumocystis jirovecii pneumonia (PJP) was associated with lower odds of IPD cases. Of alloHSCT recipients with IPD, 38.5% required intensive care, and, of deaths documented in cases over the period of review, 30% were attributable to IPD. Serotypes causing IPD matched currently available vaccines in 15/22 (68.1%) episodes. CONCLUSIONS: The incidence of IPD in alloHSCT recipients is an important cause of morbidity and mortality, with rates of disease being many fold higher than the general population. Patients with evidence of hyposplenism/asplenia define a high-risk group in the alloHSCT population for IPD, and the independent association with IPD and MMF in the adjusted model from this study requires further evaluation. The occurrence of post-transplant IPD may be reduced by measures such as vaccination with both 13-valent and 23-valent pneumococcal vaccines. TMP/SMX prophylaxis for the prevention of PJP may offer incidental protection against IPD in alloHSCT recipients.


Assuntos
Anti-Infecciosos/uso terapêutico , Antibioticoprofilaxia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Infecções Pneumocócicas/epidemiologia , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/uso terapêutico , Incidência , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Infecções Pneumocócicas/microbiologia , Estudos Retrospectivos , Fatores de Risco , Sorotipagem , Baço/anormalidades , Streptococcus pneumoniae/classificação , Transplante Homólogo , Adulto Jovem
6.
Surg Neurol Int ; 4: 137, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24233184

RESUMO

BACKGROUND: Primary intracranial germinomas are a rare subset of intracranial tumors derived from mis-incorporated germ cells within the folding neural plate during embryogenesis. Though known to arise from midline structures in the central nervous system (CNS), occurrence within the corpus callosum is exceedingly rare. CASE DESCRIPTION: We present a rare case of secreting primary intracranial germinoma with extensive intraventricular metastasis presenting as a multi-cystic butterfly lesion in the genu of the corpus callosum in a young boy. CONCLUSION: Intracranial germ cell tumors must be considered for any multi-cystic lesion arising from midline structures in the CNS in the preadult population.

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