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3.
J Phys Condens Matter ; 33(43)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34343981

RESUMO

In low-dimensional Ising spin systems, an interesting observation is the presence of step magnetization at low temperatures. Here we combine both DC and pulsed magnetic fields to study the 1/3 magnetization plateau and multiple steps in the Ising spin-chain material α-CoV2O6. Magnetization in pulsed fields is quite different from that in DC fields, showing multiple steps in an intermediate range of 4.2-6 K, inverted hysteresis below 4.2 K and asymmetric magnetization in negative fields below 11 K. We demonstrate that these unusual behaviors in magnetization are caused by the spin dynamics and the anomalous magnetocaloric effect (MCE) in α-CoV2O6, i.e., abrupt changes of sample temperature in adiabatic conditions. We successfully separate the influence between the intrinsic slow spin dynamics and the quasi-extrinsic temperature change. From the MCE, we find that some irreversible behavior is originated from the slow spin dynamics. Two different slow dynamics associated with the metastable steps are observed: one is sensitive to the slow field sweep rate at the order of ∼mT s-1and weakly depends on temperature, while the other responds to the rapid field sweep rate of ∼kT s-1and dominates at lowest temperature. We also distinguish that the metastable transition atH4is the first order and crucial for the ferrimagnetic to ferromagnetic transition. This study is useful to the understanding of multistep magnetization in α-CoV2O6and sheds light on recent experimental findings of related compounds.

4.
Eur Rev Med Pharmacol Sci ; 25(1): 86-93, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33506896

RESUMO

OBJECTIVE: Circular RNAs (circRNAs) could regulate gene expression which may induce tumor occurrence and progression. In the current study, we first investigated the expression of circMTO1 in osteosarcoma, and the underlying mechanism was further elucidated. PATIENTS AND METHODS: Circular RNA microarrays were used to identify the differential expression of circRNAs in osteosarcoma tissues and the corresponding normal tissues. qRT-PCR was used to examine the level of circMTO1 in osteosarcoma tissues and cell lines. In addition, circMTO1 overexpression was constructed using lentiviral transfection in cell lines. Subsequently, the Cell Counting Kit-8 (CCK8), cell migration and invasion, and flow cytometry were used to investigate the effect of circMTO1 on the biological functions of cells. The Western Blot and the recovery experiments were used to explore the potential mechanism. RESULTS: Here, we measured 20 circRNAs which were downregulated in osteosarcoma tissues using circRNA microarray. CircMTO1 expression was decreased in osteosarcoma cell lines. Besides, circMTO1 could inhibit cell proliferation, migration and invasion, and induced apoptosis in osteosarcoma cells. Bioinformatics analysis showed that circMTO1 serves as a sponge for miR-630 and KLF6 is a direct target of miR-630. Furthermore, circMTO1 functions through regulation of miR-630/KLF6 axis. CONCLUSIONS: Our study suggests circMTO1 could suppress osteosarcoma progression by regulating miR-630/KLF6 axis, which may highlight the diagnostic and therapeutic potential of these molecules in osteosarcoma treatment.


Assuntos
Neoplasias Ósseas/metabolismo , Fator 6 Semelhante a Kruppel/metabolismo , MicroRNAs/metabolismo , Osteossarcoma/metabolismo , RNA Circular/metabolismo , Proteínas de Ligação a RNA/metabolismo , Adolescente , Apoptose , Neoplasias Ósseas/patologia , Movimento Celular , Proliferação de Células , Células Cultivadas , Feminino , Humanos , Fator 6 Semelhante a Kruppel/genética , Masculino , MicroRNAs/genética , Osteossarcoma/patologia , RNA Circular/genética , Proteínas de Ligação a RNA/genética
5.
Am J Emerg Med ; 40: 120-126, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32001056

RESUMO

BACKGROUND: Current post-resuscitation guidelines recommend oxygen titration in adults with the return of spontaneous circulation after cardiac arrest. However, the optimal peripheral oxygen saturation (SpO2) is still unclear for post-cardiac arrest care. METHODS: We conducted a retrospective observational study of prospectively collected data of all cardiac arrest patients admitted to the intensive care units between 2014 and 2015. The main exposure was SpO2, which were interfaced from bedside vital signs monitors as 1-min averages, and archived as 5-min median values. The proportion of time spent in different SpO2 categories was included in separate multivariable regression models along with covariates. The primary outcome measure was hospital mortality and the proportion of discharged home as the secondary outcome was reported. RESULTS: 2836 post-cardiac arrest patients in ICUs of 156 hospitals were included. 1235 (44%) patients died during hospitalization and 818 (29%) patients discharged home. With multivariate regression analysis, the proportion of time spent in SpO2 of ≤89%, 90%, 91%, and 92% were associated with higher hospital mortality. The proportion of time spent in SpO2 of 95%, 96%, and 97% were associated with a higher proportion of discharged home outcome, but not associated with hospital mortality. CONCLUSIONS: In this retrospective observational study, the optimal SpO2 for patients admitted to the intensive care unit after cardiac arrest may be 95-97%. Further investigation is warranted to determine if targeting SpO2 of 95-97% would improve patient-centered outcomes after cardiac arrest.


Assuntos
Parada Cardíaca/sangue , Oxigênio/sangue , Idoso , Reanimação Cardiopulmonar , Feminino , Parada Cardíaca/mortalidade , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida
6.
Br J Anaesth ; 115 Suppl 1: i46-i57, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26174300

RESUMO

BACKGROUND: Anaesthetic drugs act at sites within the brain that undergo profound changes during typical ageing. We postulated that anaesthesia-induced brain dynamics observed in the EEG change with age. METHODS: We analysed the EEG in 155 patients aged 18-90 yr who received propofol (n=60) or sevoflurane (n=95) as the primary anaesthetic. The EEG spectrum and coherence were estimated throughout a 2 min period of stable anaesthetic maintenance. Age-related effects were characterized by analysing power and coherence as a function of age using linear regression and by comparing the power spectrum and coherence in young (18- to 38-yr-old) and elderly (70- to 90-yr-old) patients. RESULTS: Power across all frequency bands decreased significantly with age for both propofol and sevoflurane; elderly patients showed EEG oscillations ∼2- to 3-fold smaller in amplitude than younger adults. The qualitative form of the EEG appeared similar regardless of age, showing prominent alpha (8-12 Hz) and slow (0.1-1 Hz) oscillations. However, alpha band dynamics showed specific age-related changes. In elderly compared with young patients, alpha power decreased more than slow power, and alpha coherence and peak frequency were significantly lower. Older patients were more likely to experience burst suppression. CONCLUSIONS: These profound age-related changes in the EEG are consistent with known neurobiological and neuroanatomical changes that occur during typical ageing. Commercial EEG-based depth-of-anaesthesia indices do not account for age and are therefore likely to be inaccurate in elderly patients. In contrast, monitoring the unprocessed EEG and its spectrogram can account for age and individual patient characteristics.


Assuntos
Envelhecimento/fisiologia , Anestesia Geral , Anestésicos/farmacologia , Eletroencefalografia/efeitos dos fármacos , Éteres Metílicos/farmacologia , Propofol/farmacologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sevoflurano , Adulto Jovem
7.
Genet Mol Res ; 14(1): 1868-74, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25867332

RESUMO

PR genes, a type of genetic marker, are constitutively expressed at background levels, while being easily inducible by pathogenic bacteria. By using a yeast two-hybrid technique, four rice (Oryza sativa L.) OsPR1b-interacting factors were screened. Homozygous plants overexpressing OsPR1b were prepared by transgenic technology. We postulated that OsPR1b may participate in the resistance signaling pathway of rice. Of simultaneous treatments with hormones and pathogenic bacteria, exogenously applying JA and ET significantly increased the expression level of OsPR1b genes in seedlings. Compared with the control group that was inoculated with water, inoculation with a mixture of water and pathogenic bacteria hardly affected the expression level of OsPR1b gene, while cotreatment with SA and pathogenic bacteria slightly upregulated the expression level. However, cotreatment with JA or ET and pathogenic bacteria managed to significantly upregulate the expression level of the OsPR1b gene by 4.8 or 5.7 fold. PR genes, which are sensitive, are prone to many unknown factors during expression, and the detailed regulatory mechanisms in rice still require in-depth studies.


Assuntos
Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/microbiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Ciclopentanos/farmacologia , Etilenos/farmacologia , Oxilipinas/farmacologia , Melhoramento Vegetal , Proteínas de Plantas/genética , Plântula/genética , Técnicas do Sistema de Duplo-Híbrido , Regulação para Cima , Xanthomonas/patogenicidade
8.
Meat Sci ; 105: 1-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25746574

RESUMO

Ujumqin sheep are susceptible to infection by the gastrointestinal nematode Haemonchus contortus, which reduces productivity and total meat yield in sheep. Thus, the effects of green tea polyphenol (GTP) supplements (0, 2, 4, or 6g of GTP/kg feed) on dietary nutrient digestibility and meat quality in lambs infected with H. contortus were examined; control lambs were not infected. H. contortus infections did not affect digestion but the apparent digestibilities of nutrients were decreased by dietary 2g of GTP/kg feed supplementation. There was an interaction between treatment and sampling time on plasma total protein, urea nitrogen, and amino acid concentrations. The antioxidant activity and meat color of INFGTP0 lambs decreased. In conclusion, H. contortus infections in lambs decreased meat quality, but appropriate levels of dietary GTP supplementation diminished these negative effects though lower dose of GTP supplement showed negative effects on digestion.


Assuntos
Dieta/veterinária , Digestão , Hemoncose/veterinária , Músculo Esquelético/metabolismo , Polifenóis/uso terapêutico , Doenças dos Ovinos/dietoterapia , Chá/química , Aminoácidos/análise , Aminoácidos/sangue , Animais , Antioxidantes/administração & dosagem , Antioxidantes/efeitos adversos , Antioxidantes/análise , Antioxidantes/uso terapêutico , Camellia sinensis/química , China , Dieta/efeitos adversos , Fezes/química , Fezes/parasitologia , Manipulação de Alimentos , Qualidade dos Alimentos , Hemoncose/dietoterapia , Hemoncose/metabolismo , Hemoncose/parasitologia , Haemonchus/isolamento & purificação , Masculino , Carne/análise , Carne/parasitologia , Músculo Esquelético/química , Pigmentos Biológicos/análise , Pigmentos Biológicos/metabolismo , Folhas de Planta/química , Polifenóis/administração & dosagem , Polifenóis/efeitos adversos , Ovinos , Doenças dos Ovinos/sangue , Doenças dos Ovinos/metabolismo , Doenças dos Ovinos/parasitologia , Carneiro Doméstico , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
9.
Meat Sci ; 100: 10-16, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25282041

RESUMO

Twenty-four Merino lambs were randomly assigned to four treatments: control diet (CT) consisting of 300g concentrates with ad libitum Leymus chinensis hay; C with 150g (T150), 300g (T300) and 450g (T450) Suaeda glauca seed, respectively. Meat quality, fatty acid composition of meat and lipid tissue and antioxidant status of lamb were evaluated. Inclusion of S. glauca seeds significantly increased selenium (Se) concentrations of muscle. The proportions of C18:1 trans-11 in muscle, C18:2 n-6, PUFA, n-6 series fatty acids, and the ratios of P:S in rumen contents, as well as the ratios of n-6:n-3 in adipose tissue, rumen and duodenum content have been significantly (P<0.05) improved with supplementation of S. glauca seeds to lamb diets. No significant effect was found on antioxidant status. The results suggest that S. glauca seed supplementation in lamb diets may change fatty acid composition in tissues and content of digestive tract.


Assuntos
Antioxidantes/metabolismo , Chenopodiaceae , Suplementos Nutricionais , Ácidos Graxos/metabolismo , Trato Gastrointestinal/metabolismo , Carne/análise , Músculos/metabolismo , Tecido Adiposo/metabolismo , Animais , Dieta , Duodeno/metabolismo , Conteúdo Gastrointestinal/química , Humanos , Carne/normas , Distribuição Aleatória , Rúmen/metabolismo , Plantas Tolerantes a Sal , Sementes , Selênio/metabolismo , Ovinos
10.
Parasite Immunol ; 36(2): 100-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24558656

RESUMO

Direct inhibitory effects of tannic acid on Haemonchus contortus viability were studied in vitro using the larval migration inhibition (LMI) assay. Sheep white blood cells (WBC) were preincubated with 5 and 50 lg/mL tannic acid or not followed by whole H. contortus antigen (WHA). Cells were harvested at 24 h post-incubation to test host immune responses. Concentrations of 50, 100, 500, 1000, 3000 and 5000 lg/mL tannic acid inhibited larvae migration by 19.8, 42.4, 46.3, 92.0, 93.7 and 100%, respectively, within 96 h post-incubation (P < 0.001). The relative mRNA levels of interferon (IFN)-c, interleukin (IL)-2, IL-4 and IL-10 were increased by WHA stimulation without tannic acid. However, the increased effects on IFN-c and IL-2 were inhibited by tannic acid preincubation (P < 0.001), while the increases in IL-4 and IL-10 were greatly enhanced by tannic acid preincubation (P < 0.001). Changes in protein levels of all cytokines essentially paralleled the changes in their corresponding mRNA levels. In conclusion, tannic acid is directly harmful to larvae in a dose- and time-dependent manner and modulates immune responses of sheep WBC stimulated by H. contortus antigen by inhibiting Th1 cytokines and increasing Th2 cytokine expression in vitro.


Assuntos
Antígenos de Helmintos/imunologia , Citocinas/biossíntese , Haemonchus/efeitos dos fármacos , Haemonchus/imunologia , Leucócitos/imunologia , Ovinos/imunologia , Taninos/farmacologia , Animais , Proliferação de Células , Citocinas/imunologia , Haemonchus/fisiologia , Interleucina-10/biossíntese , Interleucina-10/imunologia , Interleucina-2/biossíntese , Interleucina-2/imunologia , Interleucina-4/biossíntese , Interleucina-4/imunologia , Larva/imunologia , Masculino
11.
J Dairy Sci ; 96(9): 5901-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23871369

RESUMO

This study was conducted to evaluate the effects of chestnut tannins (CT) on performance and antioxidative status of transition dairy cows. Twenty multiparous Chinese Holstein cows in late gestation were paired according to expected calving date and randomly assigned either to a diet supplemented with CT (CNT, 10 g of CT/kg of diet, dry matter basis) or to an unsupplemented control (CON) diet from 3 wk prepartum to 3 wk postpartum. Blood samples were taken on d -21, 1, 7, and 21 relative to calving for analysis of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), and malondialdehyde (MDA). Liver samples were taken by puncture biopsy on d 1 and 21 relative to calving for analysis of SOD, GSH-Px, and MDA. Data were analyzed for a completely randomized block design with repeated measures. The addition of CT had no significant effects on dry matter intake, body weight, body condition score, milk yield, 3.5% fat-corrected milk yield, and milk composition but did decrease milk MDA and somatic cell score in transition dairy cows. Dry matter intake decreased from d -21 to 0 and increased from d 1 to 21 relative to calving across treatments. During the experimental period, body weight and body condition score decreased, whereas milk MDA and somatic cell score increased across treatments. A time effect was also observed for plasma MDA, which peaked on d 1 relative to calving and remained higher than that on d -21 relative to calving across treatments. Addition of CT decreased MDA concentrations in plasma and liver. Neither time nor CT × time effects were observed for SOD and T-AOC in plasma and SOD and GSH-Px in liver; a time effect was observed for plasma GSH-Px, which peaked on d 1 relative to calving and remained higher than those on d -21 relative to calving across treatments. Addition of CT increased SOD, GSH-Px, and T-AOC activities in plasma and SOD and GSH-Px activities in liver. In conclusion, addition of CT might inhibit lipid peroxidation and increase antioxidant enzymes activities in plasma and liver of transition dairy cows. Supplementation of CT may be a feasible means to improve the antioxidative status of transition dairy cows.


Assuntos
Antioxidantes/análise , Período Periparto/efeitos dos fármacos , Extratos Vegetais/farmacologia , Taninos/farmacologia , Animais , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Fagaceae , Feminino , Glutationa Peroxidase/análise , Glutationa Peroxidase/sangue , Lactação/efeitos dos fármacos , Lactação/fisiologia , Fígado/química , Malondialdeído/análise , Malondialdeído/sangue , Período Periparto/fisiologia , Gravidez , Superóxido Dismutase/análise , Superóxido Dismutase/sangue , Madeira
12.
J Anim Sci ; 91(2): 764-71, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23307846

RESUMO

This study was conducted to investigate the influence of pasture intake on meat quality, lipid oxidation, and fatty acid composition of geese. One hundred twenty Dongbei White male geese (a local breed; BW = 878 ± 13 g; 28 d old) were randomly and equally divided into 2 treatments with 6 pens of 10 geese per treatment. The 2 treatments consisted of birds fed ad libitum a corn-based feed. One-half of the birds had no access to pasture (control) while the other half had access to an alfalfa (Medicago sativa)-based pasture (pasture). The study lasted 42 d. Body weight and feed intake were recorded weekly. At the end of the study, geese were slaughtered to collect meat samples. Results showed that pasture intake reduced subcutaneous fat thickness (P < 0.05) and abdominal fat yield (P < 0.05) of geese compared with control. Geese with access to pasture had greater cooking loss (P < 0.05) and lightness (L*) value (P < 0.05) and lower pH at 24 h postmortem (pH24; P < 0.05) and thiobarbituric acid reacting substance values (P < 0.05) at 0 and 30 min of forced oxidation. Moreover, pasture intake increased linolenic acid (C18:3n-3; P < 0.05) and eicosapentaenoic acid (C20:5n-3; P < 0.05) and reduced the n-6:n-3 ratio (P < 0.05) in the breast muscle of geese compare with the control. In conclusion, pasture intake did not enhance growth performance but improved carcass characteristics and meat quality and changed fatty acid composition of geese.


Assuntos
Ácidos Graxos/química , Peroxidação de Lipídeos/fisiologia , Carne/normas , Ração Animal , Criação de Animais Domésticos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Anseriformes/crescimento & desenvolvimento , Anseriformes/fisiologia , Composição Corporal , Dieta/veterinária , Concentração de Íons de Hidrogênio , Masculino , Músculo Esquelético/química
13.
J Anim Physiol Anim Nutr (Berl) ; 97(3): 475-84, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22416977

RESUMO

Tea catechins (TC) are polyphenols that have potent antioxidant activity. The objectives of this study were to determine the effects of TC on antioxidant status of hepatocytes challenged with H2 O2 . Primary hepatocytes of goat were exposed to 1 mm H2 O2 without or with 5, 50 and 500 µg/ml TC. The cells were harvested at 48 h post-treatment to determine effects of TC on proliferation, apoptotic features and membrane integrity of cells, and expression of genes and activities of antioxidant enzymes. H2 O2 exposure caused damage to cells (p < 0.001). A lower concentration of TC (5 µg/ml) displayed a protective effect by inhibiting exorbitant cell proliferation and DNA degradation. Both H2 O2 exposure and TC pre-incubation affected expression of antioxidant enzymes at mRNA and protein levels (p < 0.001). The activities of catalase (CAT) (p = 0.027), CuZn-superoxide dismutase (CuZn-SOD) (p < 0.001) and glutathione peroxidase (GPx) (p < 0.001) increased with TC pre-incubation followed by H2 O2 challenge. Changes of CuZn-SOD activity induced by H2 O2 and TC basically paralleled the changes in the corresponding mRNA and protein levels, but the correlation in CAT and GPx expression displayed slightly different patterns at different concentrations of TC. These findings infer that oxidative stress can induce deleterious cellular responses and this unfavourable condition may be alleviated by treatment with TC.


Assuntos
Antioxidantes/metabolismo , Camellia sinensis/química , Catecóis/farmacologia , Cabras , Hepatócitos/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Animais , Catecóis/química , Proliferação de Células , Células Cultivadas , Relação Dose-Resposta a Droga , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hepatócitos/citologia , Hepatócitos/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
14.
Int J Immunopathol Pharmacol ; 25(3): 627-36, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23058013

RESUMO

Phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway plays a crucial role in the formation and progression of many malignancies, and has been shown to be an important therapeutic target for cancer. In the present study, human gastric adenocarcinoma tissues of different grades (N=45) were collected. The protein expression of PI3Kp85α and phosphorylated AKT (p-AKT) was evaluated immunohistochemically in the biopsy samples. PI3K/AKT pathway was blocked by constructed recombinant small hairpin RNA adenovirus vector rAd5-PI3Kp85α (rAd5-P) used to transfect into human gastric cancer SGC-7901cell line. The transfection efficiency of rAd5-P in SGC-7901 cells was observed under fluorescent microscope. The expression of PI3Kp85α, p-AKT, Ki-67 and matrix metallopeptidase-2 (MMP-2) was detected by real-time PCR and Western blot assays. Cell proliferative activities and metastatic capabilities were determined by MTT and Transwell assays. As a consequence, the protein expression of PI3Kp85α and p-AKT was respectively observed in 80.0% and 82.2% gastric adenocarcinoma tissues, elevating with the ascending order of tumor malignancy. Targeted blockade of PI3K pathway decreased the expression of PI3Kp85α, p-AKT, Ki-67 and MMP-2, and inhibited the proliferative activities and metastatic capabilities of gastric cancer cells. In conclusion, PI3Kp85α and p-AKT were strongly expressed in gastric adenocarcinoma tissues, and targeted blockade of PI3K pathway may inhibit gastric cancer growth and metastasis through down-regulation of Ki-67 and MMP-2 expression. PI3K/AKT pathway may represent an important therapeutic target for gastric cancer.


Assuntos
Adenocarcinoma/enzimologia , Proliferação de Células , Classe Ia de Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Neoplasias Gástricas/enzimologia , Adenocarcinoma/genética , Adenocarcinoma/secundário , Biópsia , Western Blotting , Linhagem Celular Tumoral , Movimento Celular , Classe Ia de Fosfatidilinositol 3-Quinase/genética , Humanos , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Microscopia de Fluorescência , Gradação de Tumores , Invasividade Neoplásica , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Interferência de RNA , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Fatores de Tempo , Transfecção
15.
J Anim Sci ; 90(13): 4764-70, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22871939

RESUMO

This study was conducted to evaluate the effects of providing shade on growth performance, welfare, and meat quality of grazing sheep under high ambient temperature. A total of 120 healthy male Ujumqin wool sheep (a local breed; BW = 18.7 ± 1.27 kg; 14 wk old) were randomly and equally divided into shaded and unshaded treatments with 3 pens per treatment. Sheep were grazed on an unshaded pastureland from 0600 to 1000 h and 1400 to 1800 h. During other times, sheep were confined in shaded or unshaded pens. Body weight was recorded on d 1 and 42 of the experiment. Rectal temperature and respiration rate were recorded on d 7, 14, 21, 28, 35, and 42. At end of the trial, sheep were blood sampled and slaughtered to collect meat samples. Respiration rate was greater (P < 0.05) in the unshaded sheep than shaded sheep on d 14, 21, 28, 35, and 42 of the trial whereas no significant differences were found on d 7. Moreover, no differences were observed in final BW, ADG, or rectal temperature throughout the trial. The pH at 24 h postmortem (pH(24)) and cooking loss were greater (P < 0.01) in unshaded than shaded sheep. On the contrary, lightness (L*), redness (a*) and yellowness (b*) values at 24 h postmortem were lower (P < 0.05) in unshaded versus shaded sheep. The sheep in the unshaded group had a greater (P < 0.05) cortisol concentration compared with the shaded group. Sheep in the shaded group had lower creatine kinase activity (P < 0.01) as well as observed for glucose (P < 0.05), triiodothyronine (P < 0.01), and thyroxine (P < 0.05) concentrations and white blood cell count (P < 0.05). Compared with the unshaded group, sheep in the shaded group had a greater lymphocytes (LYM) count (P < 0.05). In contrast, the opposite was true for neutrophils (NEU) count (P < 0.01) and NEU:LYM ratio (P < 0.01). In conclusion, the shade cloth, although not enhancing ADG, improved meat quality traits and certain stress parameters in grazing sheep reared under high ambient temperature.


Assuntos
Criação de Animais Domésticos/métodos , Bem-Estar do Animal , Carne/normas , Carneiro Doméstico/fisiologia , Animais , Análise Química do Sangue , China , Materiais de Construção , Testes Hematológicos , Temperatura Alta/efeitos adversos , Masculino , Distribuição Aleatória , Carneiro Doméstico/crescimento & desenvolvimento
16.
J Anim Physiol Anim Nutr (Berl) ; 96(6): 1127-35, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21929728

RESUMO

The study was conducted to evaluate the effects of different lairage time after 8 h road transport on some blood indicators of welfare and meat quality traits in sheep. A total of 84 Ujimqin male sheep (average body weight 27.5 kg, 6 months old) were randomly allotted to one of seven groups: one control group (untransported) and six lairage groups (8 h road transport with 0, 2, 6, 12, 24 and 48 h lairage times respectively). No significant lairage time effects were observed on weight loss. Sheep in 48 h group showed lower hot carcass weight, dressing percentage and higher pH(24 h) than that in other groups. The total haem pigment contents in sheep meat rose and were higher in 24 and 48 h groups than that in the control group. After transport, sheep in 0, 2, 24 and 48 h groups showed higher serum creatine kinase activities, cortisol and glucose concentrations than that in control group. Sheep in lairage groups had higher serum triiodothyronine and thyroxine levels compared with the control sheep. Sheep in 48 h group showed significant higher packed cell volume, total protein and blood urea nitrogen than that in other groups. Compared with the control group, the white blood cell counts were higher in 0 and 48 h groups. The neutrophil counts in 24 or 48 h groups were higher than that in the control group. The opposite was true for lymphocyte counts. A 6-12 h lairage is recommended in terms of the present transported pattern.


Assuntos
Bem-Estar do Animal , Carne/normas , Meios de Transporte , Matadouros , Criação de Animais Domésticos , Animais , Masculino , Ovinos/sangue , Estresse Fisiológico , Fatores de Tempo
17.
J Anim Sci ; 89(11): 3742-51, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21680786

RESUMO

The aim of this study was to determine the effects of 8 h of road transportation on physiological responses and meat quality traits of sheep at 6, 12, and 24 mo of age. Seventy-two male sheep were equally divided into transported (TRANS) and nontransported (CON) treatments (n = 36), and each treatment was subdivided into 3 groups by age (n = 12). Sheep in CON groups were weighed, blood sampled, and slaughtered, whereas sheep in TRANS groups were weighed, transported, blood sampled, and slaughtered to collect meat samples. The BW of sheep in TRANS groups was reduced significantly (P < 0.001) compared with CON sheep, and older sheep lost more BW than younger animals. However, dressing percentages of TRANS sheep were significantly (P < 0.001) greater than those of CON sheep. Some meat quality variables were affected by transportation, and responses of different ages of sheep varied. Total pigment content and lipid oxidation of LM and gluteus medius of TRANS sheep increased significantly (P < 0.001) compared with CON sheep. Cooking loss of LM and gluteus medius was influenced significantly (P < 0.01) by interaction effect between transportation and age, and the values for 6-mo-old TRANS sheep were less than those of CON sheep. Serum total protein (P = 0.036), globulin (P = 0.026), triglyceride (P < 0.001), and total cholesterol concentrations (P = 0.028) of TRANS sheep decreased compared with CON sheep. Serum NEFA concentration of TRANS sheep increased in relation to CON sheep with a significant interaction (P < 0.001) between transportation and age effect. Numbers of white blood cells were influenced (P = 0.002) by an interaction effect between transportation and age, and values for 6-mo-old sheep were not influenced by transportation. Numbers of platelets were influenced (P = 0.014) by age; they decreased more in 6-mo-old sheep than in older sheep. Transportation and age had no significant effects (P > 0.05) on packed cell volume and lymphocyte number. Serum creatine kinase activities in TRANS sheep were affected (P = 0.01) by an interaction effect between transportation and age. The 2-thiobarbituric acid reactive substances in serum of TRANS sheep increased (P = 0.009) with the greatest change for 6-mo-old compared with older sheep. In conclusion, 8 h of road transportation resulted in greater heme pigment concentrations but improved meat tenderness and induced physiological responses of sheep. However, different ages of sheep showed different responses to the present transportation pattern.


Assuntos
Carne/normas , Músculo Esquelético/fisiologia , Ovinos/fisiologia , Estresse Fisiológico/fisiologia , Meios de Transporte/métodos , Fatores Etários , Animais , Peso Corporal/fisiologia , Colesterol/sangue , Ácidos Graxos não Esterificados/sangue , Globulinas/análise , Hematócrito/veterinária , Contagem de Leucócitos/veterinária , Contagem de Linfócitos/veterinária , Masculino , Distribuição Aleatória , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Triglicerídeos/sangue
18.
J Phys Condens Matter ; 21(2): 025508, 2009 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-21813985

RESUMO

We have used first-principles calculations to investigate the electronic structure of the new oP8 phase of sodium which was experimentally reported recently (Gregoryanz et al 2008 Science 320 1054). Our results show the transition from I-43d to oP8 structure, which happens at room temperature, can also happen at 0 K. The I-43d structure will change to the oP8 structure at about 155 GPa and 0 K, rather than the CsIV structure at 190 GPa and 0 K, as the previous studies (Neaton et al 2001 Phys. Rev. Lett. 86 2830) predicted. It is also found that the oP8 structure forms a new nonequilateral triangle Na(3) structure and mainly distributes charge accumulation in the voids of the structure, rather than within the Na(3) triangles. Electronic density of states analysis shows that the oP8 structure opens a deeper pseudogap close to the Fermi level through symmetry breaking of the structure compared with that of the I-43d structure. Together with its unusual charge density distribution, it is found that the Peierls mechanism works for the transition to the oP8 structure. Differing from previous results about the Peierls mechanism of light alkali metals, the unit which produces a one-dimensional charge density wave is the Na(3) cluster instead of the pairing mechanism.

19.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 6021-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17281634

RESUMO

The moments acting on the lower limb joints influence the life of the arthrosis. These loads may depend on the footwear and action style. The footwear factor was studied with three-dimensional gait measure system. Five young women in their 20s, wear 7 cm high-heeled shoes and sneakers, and walked in 10 m gait laboratory walkway. Inversed dynamics was used to analysis the torques at the ankle, knee and hip. Results showed that peak adduction moments at the knee and ankle increased and flexion/extension moments at hip increased with high-heel shoes compared with the sneakers. The high-heeled shoes result in greater load in lower limb joints especial to the knee and hip.

20.
Yi Chuan Xue Bao ; 18(5): 415-23, 1991.
Artigo em Chinês | MEDLINE | ID: mdl-1782000

RESUMO

This paper reports the results of blood-group and plasma protein polymorphism of eleven Chinese native fowl breeds. 1. The distribution frequencies of the blood-group genes (3 loci 12 alleles) in eleven Chinese native fowl breeds were significantly different in A and C loci, but not significant in B locus. The coefficients of homozygosity of blood-group gene in all breeds were almost similar, except in Gushi and Chonren pitted chickens. The distribution of blood-group factors in all breeds was extensive, and this means that the selection potential in these local breeds was very large. 2. The gene frequencies of alkaline phosphatase (Akp and Akp-2) transferrin (Tf) in some breeds were more different, while that of esterase (Es-1) was less different. Among Chinese Japanese and American-European native breeds, the difference of gene frequencies of esterase was greater, while that of alkaline phosphatase and transferrin was smaller. It showed the identity or diversity in breed origin and evolution in these Chinese local breeds and Japanese or American-European native breeds. 3. The cluster analysis of the eleven Chinese native fowl breeds showed that these breeds could be divided into four groups: White ear-lobe- Shouguang- Luyuan chickens; Xiaoshan-Xianju- Pudong chickens; Langshan- Taihe Silky- Beijing Youkei chickens and Gushi-Chonren pitted chickens.


Assuntos
Antígenos de Grupos Sanguíneos/genética , Proteínas Sanguíneas/genética , Galinhas/genética , Polimorfismo Genético , Fosfatase Alcalina/genética , Animais , Galinhas/sangue , Frequência do Gene , Receptores da Transferrina/genética
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