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1.
Phys Rev Lett ; 132(11): 116101, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38563927

RESUMEN

Chemical short-range order is believed to be a key contributor to the exceptional properties of multicomponent alloys. However, its direct validation and confirmation has been highly elusive in most compounds. Recent studies for equiatomic NiCoCr alloys have shown that thermal treatments (i.e., annealing and aging) may facilitate and manipulate such ordering. In this work, by using molecular simulations, we show that nanomechanical probes, such as nanoindentation, may be utilized toward further manipulation of chemical short-range order, providing explicit validation pathways. By using well established interatomic potentials, we perform hybrid molecular-dynamics-Monte Carlo at room temperature to demonstrate that particular dwell nanoindentation protocols can lead, through thermal Monte Carlo equilibration, to local reorganization under the indenter tip, toward a density-wave stripe pattern. We characterize the novel density-wave structures, which are highly anisotropic and dependent on local, nanoindentation-induced stress concentrations, and we show how they deeply originate from intrinsic features of interelemental interactions. Furthermore, we show that these novel patterns consistently scale with the incipient plastic zone, under the indenter tip, justifying their observation at experimentally feasible nanoindentation depths.

2.
J Endocrinol Invest ; 46(4): 679-686, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36219315

RESUMEN

BACKGROUND AND AIMS: This study aimed to evaluate the relationships of serum testosterone with dyslipidemia and blood lipid levels and test whether obesity mediated these associations by gender in Chinese rural population. METHODS AND RESULTS: A total of 6150 subjects were finally analyzed in this study. Serum testosterone for each subject was detected by liquid chromatography equipped with tandem mass spectrometry. Logistic regression and linear regression were employed to evaluate the associations of serum testosterone with the prevalence of dyslipidemia and blood lipid levels. Mediation analysis was conducted to identify the mediation effects of obesity on the relationship between serum testosterone and dyslipidemia. After adjusting for multiple confounders, per unit change in serum ln-testosterone levels was associated with a decreased prevalent dyslipidemia in men (odds ratio (OR): 0.785, 95% confidence interval (CI) (0.708, 0.871)). Males with the levels of serum testosterone in the third or fourth quartiles had a 49.4% (OR: 0.506, 95% CI 0.398, 0.644) or 67.1% (OR: 0.329, 95% CI 0.253, 0.428) significantly lower odds of prevalence of dyslipidemia. In addition, a onefold increase in ln-testosterone was related to a 0.043 mmol/L (95% CI 0.028, 0.059) increase in high-density lipoprotein cholesterol (HDL-C) in men. Results of the mediation analysis suggested that obesity played a partial role in the association of testosterone with dyslipidemia in men. CONCLUSIONS: These findings suggested that serum testosterone levels were negatively associated with lipid levels and prevalent dyslipidemia, and obesity mediated the effects of serum testosterone on dyslipidemia in men, implying that obesity prevention should be highlighted to decrease the prevalence of dyslipidemia related to changes in testosterone levels.


Asunto(s)
Dislipidemias , Población Rural , Masculino , Humanos , Estudios de Cohortes , Obesidad/epidemiología , Obesidad/complicaciones , Dislipidemias/epidemiología , Dislipidemias/complicaciones , Lípidos , HDL-Colesterol , Testosterona , China/epidemiología , Triglicéridos
3.
Br J Nutr ; 126(4): 510-517, 2021 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-33143765

RESUMEN

To evaluate the impacts of guanidinoacetic acid (GAA) and coated folic acid (CFA) on growth performance, nutrient digestion and hepatic gene expression, fifty-two Angus bulls were assigned to four groups in a 2 × 2 factor experimental design. The CFA of 0 or 6 mg/kg dietary DM folic acid was supplemented in diets with GAA of 0 (GAA-) or 0·6 g/kg DM (GAA+), respectively. Average daily gain (ADG), feed efficiency and hepatic creatine concentration increased with GAA or CFA addition, and the increased magnitude of these parameters was greater for addition of CFA in GAA- diets than in GAA+ diets. Blood creatine concentration increased with GAA or CFA addition, and greater increase was observed when CFA was supplemented in GAA+ diets than in GAA- diets. DM intake was unchanged, but rumen total SCFA concentration and digestibilities of DM, crude protein, neutral-detergent fibre and acid-detergent fibre increased with the addition of GAA or CFA. Acetate:propionate ratio was unaffected by GAA, but increased for CFA addition. Increase in blood concentrations of albumin, total protein and insulin-like growth factor-1 (IGF-1) was observed for GAA or CFA addition. Blood folate concentration was decreased by GAA, but increased with CFA addition. Hepatic expressions of IGF-1, phosphoinositide 3-kinase, protein kinase B, mammalian target of rapamycin and ribosomal protein S6 kinase increased with GAA or CFA addition. Results indicated that the combined supplementation of GAA and CFA could not cause ADG increase more when compared with GAA or CFA addition alone.


Asunto(s)
Alimentación Animal , Bovinos/crecimiento & desarrollo , Ácido Fólico/administración & dosificación , Glicina/análogos & derivados , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Creatina , Detergentes , Dieta/veterinaria , Suplementos Dietéticos , Digestión , Expresión Génica , Glicina/administración & dosificación , Factor I del Crecimiento Similar a la Insulina , Hígado , Masculino , Nutrientes , Fosfatidilinositol 3-Quinasas , Rumen
4.
Br J Nutr ; 125(3): 251-259, 2021 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-32718368

RESUMEN

Coated copper sulphate (CCS) could be used as a Cu supplement in cows. To investigate the influences of copper sulphate (CS) and CCS on milk performance, nutrient digestion and rumen fermentation, fifty Holstein dairy cows were arranged in a randomised block design to five groups: control, CS addition (7·5 mg Cu/kg DM from CS) or CCS addition (5, 7·5 and 10 mg Cu/kg DM from CCS, respectively). When comparing Cu source at equal inclusion rates (7·5 mg/kg DM), cows receiving CCS addition had higher yields of fat-corrected milk, milk fat and protein; digestibility of DM, organic matter (OM) and neutral-detergent fibre (NDF); ruminal total volatile fatty acid (VFA) concentration; activities of carboxymethyl cellulase, cellobiase, pectinase and α-amylase; populations of Ruminococcus albus, Ruminococcus flavefaciens and Fibrobacter succinogenes; and liver Cu content than cows receiving CS addition. Increasing CCS addition, DM intake was unchanged, yields of milk, milk fat and protein; feed efficiency; digestibility of DM, OM, NDF and acid-detergent fibre; ruminal total VFA concentration; acetate:propionate ratio; activity of cellulolytic enzyme; populations of total bacteria, protozoa and dominant cellulolytic bacteria; and concentrations of Cu in serum and liver increased linearly, but ruminal propionate percentage, ammonia-N concentration, α-amylase activity and populations of Prevotella ruminicola and Ruminobacter amylophilus decreased linearly. The results indicated that supplement of CS could be substituted with CCS and addition of CCS improved milk performance and nutrient digestion in dairy cows.


Asunto(s)
Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Sulfato de Cobre/administración & dosificación , Suplementos Dietéticos , Animales , Bovinos , Digestión/efectos de los fármacos , Enzimas/efectos de los fármacos , Femenino , Fermentación/efectos de los fármacos , Lactancia/efectos de los fármacos , Hígado/metabolismo , Microbiota/efectos de los fármacos , Nutrientes/metabolismo , Rumen/metabolismo
5.
Br J Nutr ; 126(9): 1288-1295, 2021 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-33413702

RESUMEN

To investigate the influences of dietary riboflavin (RF) addition on nutrient digestion and rumen fermentation, eight rumen cannulated Holstein bulls were randomly allocated into four treatments in a repeated 4 × 4 Latin square design. Daily addition level of RF for each bull in control, low RF, medium RF and high RF was 0, 300, 600 and 900 mg, respectively. Increasing the addition level of RF, DM intake was not affected, average daily gain tended to be increased linearly and feed conversion ratio decreased linearly. Total tract digestibilities of DM, organic matter, crude protein (CP) and neutral-detergent fibre (NDF) increased linearly. Rumen pH decreased quadratically, and total volatile fatty acids (VFA) increased quadratically. Acetate molar percentage and acetate:propionate ratio increased linearly, but propionate molar percentage and ammonia-N content decreased linearly. Rumen effective degradability of DM increased linearly, NDF increased quadratically but CP was unaltered. Activity of cellulase and populations of total bacteria, protozoa, fungi, dominant cellulolytic bacteria, Prevotella ruminicola and Ruminobacter amylophilus increased linearly. Linear increase was observed for urinary total purine derivatives excretion. The data suggested that dietary RF addition was essential for rumen microbial growth, and no further increase in performance and rumen total VFA concentration was observed when increasing RF level from 600 to 900 mg/d in dairy bulls.


Asunto(s)
Microbiota , Riboflavina/administración & dosificación , Rumen , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Bovinos , Suplementos Dietéticos/análisis , Digestión , Ácidos Grasos Volátiles , Masculino , Nutrientes , Propionatos , Rumen/microbiología
6.
J Endocrinol Invest ; 44(12): 2581-2592, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33829394

RESUMEN

AIMS: To evaluate the associations of morning serum cortisol levels with obesity defined by different indices in Chinese rural populations. MATERIALS AND METHODS: A cross-sectional study was performed including 6198 participants (2566 males and 3632 females). Serum cortisol was collected in morning and quantified by liquid chromatography-tandem mass spectrometry. Obesity was defined by body mass index (BMI), body fat percentage (BFP), waist-to-height ratio (WHtR), waist circumference (WC), visceral fat index (VFI) and waist-to-hip ratio (WHR). Both multivariable liner regression, logistic regression and restrictive cubic splines models were used to estimate the gender-specific relationships between cortisol levels and obesity defined by different indices, respectively. RESULTS: After adjusting for potential confounders, serum cortisol was negatively associated with different obesity measures, except obese females defined by BFP (for instance, overall obesity defined by BMI, Quartile 4 vs. Quartile 1, odds ratio (OR) = 0.25, 95% confidence interval (CI):0.15, 0.41 in males, and OR = 0.58, 95% CI: 0.42,0.80 in females, central obesity defined by WC, OR = 0.52, 95% CI:0.39,0.69 in males and OR = 0.63, 95% CI:0.51,0.77 in females). Similarly, restrictive cubic splines showed the nonlinear relationship between high levels of cortisol and different obesity indices. Furthermore, ROC curve analysis indicated that cortisol could improve the discrimination of model with common biomarkers. CONCLUSION: Morning serum cortisol were negatively related to obesity defined by different indices in Chinese rural populations. In addition, cortisol could be as a biomarker for prediction of obesity in males.


Asunto(s)
Hidrocortisona , Grasa Intraabdominal , Obesidad , Biomarcadores/análisis , Biomarcadores/sangre , Índice de Masa Corporal , Causalidad , China/epidemiología , Estudios Transversales , Femenino , Humanos , Hidrocortisona/análisis , Hidrocortisona/sangre , Grasa Intraabdominal/metabolismo , Grasa Intraabdominal/patología , Masculino , Persona de Mediana Edad , Obesidad/sangre , Obesidad/diagnóstico , Obesidad/epidemiología , Curva ROC , Medición de Riesgo/métodos , Factores de Riesgo , Población Rural/estadística & datos numéricos , Circunferencia de la Cintura
7.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(6): 1032-1036, 2021 Dec 18.
Artículo en Zh | MEDLINE | ID: mdl-34916677

RESUMEN

OBJECTIVE: To investigate the clinical characteristics, risk factors and prognosis of ulcerative keratitis (UK) in patients with rheumatoid arthritis (RA). METHODS: Sixteen patients with UK (the UK group) were screened among 4 773 RA patients hospitalized at Peking University People's Hospital from January 2003 to May 2021, and 72 patients with RA without UK in the control group were selected by propensity score matching (PSM). The clinical features, laboratory data and medications between the two groups were collected and analyzed. RESULTS: The average age of the patients with RA was 60 years at the time of the complication of UK. UK appeared on average in the 16th year of RA, with the majority of UK occurring in the 7th year of RA and beyond (14 cases), however, a minority of UK was the first symptom of RA (1 case). UK associated with RA manifested as simple marginal UK in 8 cases, marginal UK with perforation in 5 cases, marginal UK with uveitis in 2 cases and central UK with perforation in 1 case. The number of swollen joints was significantly higher in the UK group than in the control group [6.0(2.5, 23.0) vs. 3.0(1.0, 9.8), Z=-2.047, P=0.041], and the proportion of secondary Sjögren syndrome (SS, 37.5% vs. 6.9%, χ2=11.175, P=0.004) and interstitial lung disease (ILD, 37.5% vs. 8.3%, χ2=9.456, P=0.008) were significantly higher in the RA patients with UK than the patients without UK. The uses of sulfasalazine (12.5% vs. 48.6%, χ2=7.006, P=0.008), leflunomide (31.3% vs. 63.9%, χ2=5.723, P=0.017) and gold salt(6.3% vs. 33.8%, χ2=4.841, P=0.032)were significantly lower in the UK group than in the control group. However, there was no statistically significant comparison between the two groups for the 28-joint disease activity score-erythrocyte sedimentation rate (5.3±1.8 vs. 5.1±1.6, t=0.309, P=0.761). Logistic analysis showed the number of swollen joints (OR=1.148), secondary SS (OR=79.118), complicated with ILD (OR=6.596) and the use of sulfasalazine (OR=0.037) were independent relevant factors (P < 0.05) for UK in RA patients. CONCLUSION: The number of swollen joints, secondary SS, complicated with ILD and the use of sulfasalazine are independent relevant factors for UK in patients with RA.


Asunto(s)
Artritis Reumatoide , Úlcera de la Córnea , Artritis Reumatoide/complicaciones , Artritis Reumatoide/epidemiología , Úlcera de la Córnea/epidemiología , Úlcera de la Córnea/etiología , Humanos , Persona de Mediana Edad , Grupos Minoritarios , Factores de Riesgo
8.
Br J Nutr ; 123(10): 1109-1116, 2020 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-31992377

RESUMEN

This study evaluated the effects of rumen-protected folic acid (RPFA) and betaine (BT) on growth performance, nutrient digestion and blood metabolites in bulls. Forty-eight Angus bulls were blocked by body weight and randomly assigned to four treatments in a 2 × 2 factorial design. BT of 0 or 0·6 g/kg DM was supplemented to diet without or with the addition of 6 mg/kg DM of folic acid from RPFA, respectively. Average daily gain increased by 25·2 and 6·29 % for addition of BT without RPFA and with RPFA, respectively. Digestibility and ruminal total volatile fatty acids of neutral-detergent fibre and acid-detergent fibre increased, feed conversion ratio and blood folate decreased with the addition of BT without RPFA, but these parameters were unchanged with BT addition in diet with RPFA. Digestibility of DM, organic matter and crude protein as well as acetate:propionate ratio increased with RPFA or BT addition. Ruminal ammonia-N decreased with RPFA addition. Activity of carboxymethyl cellulase, cellobiase, xylanase, pectinase and protease as well as population of total bacteria, protozoa, Fibrobacter succinogenes and Ruminobacter amylophilus increased with RPFA or BT addition. Laccase activity and total fungi, Ruminococcus flavefaciens and Prevotella ruminicola population increased with RPFA addition, whereas Ruminococcus albus population increased with BT addition. Blood glucose, total protein, albumin, growth hormone and insulin-like growth factor-1 increased with RPFA addition. Addition of RPFA or BT decreased blood homocysteine. The results indicated that addition of BT stimulated growth and nutrient digestion in bulls only when RPFA was not supplemented.


Asunto(s)
Betaína/administración & dosificación , Bovinos/crecimiento & desarrollo , Suplementos Dietéticos , Digestión/efectos de los fármacos , Ácido Fólico/administración & dosificación , Rumen/metabolismo , Alimentación Animal/análisis , Animales , Ácidos Grasos Volátiles/metabolismo , Fermentación/efectos de los fármacos , Microbioma Gastrointestinal/efectos de los fármacos , Masculino
9.
J Eur Acad Dermatol Venereol ; 34(10): 2308-2317, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32277496

RESUMEN

BACKGROUND: Hyperthermia upregulates DNAJA4, a member of heat shock proteins (HSPs) 40 family, in human keratinocytes and HPV-infected tissue. DNAJA4 deficiency enhances growth arrest induced by hyperthermia. Clusterin (CLU) and phosphorylated ERK (p-ERK) play a role in regulating cell proliferation and apoptosis, under environmental stress. OBJECTIVES: To examine the downstream molecules and signalling pathways of DNAJA4 and assess their roles in cell cycle and apoptosis of keratinocytes in response to hyperthermia. METHODS: Wild-type and DNAJA4-knockout (KO) HaCaT cells were exposed to either 44 °C (hyperthermia) or 37 °C (control) for 30 min. The expression levels of CLU and p-ERK were determined by RT-PCR and Western blotting. RNAi and PD98059 were used to inhibit the expression of CLU and p-ERK, respectively. Cell viability, cell cycle and apoptosis were analysed by MTS assay and flow cytometry. Fresh biopsy samples of human normal foreskin or condyloma acuminatum (CA) were utilized to examine the expression of CLU and p-ERK after ex vivo culture at 44 °C. RESULTS: The expression of CLU and p-ERK was significantly increased by hyperthermia treatment at 44 °C in HaCaT cells, foreskin and HPV-infected tissues. In HaCaT cells subjected to hyperthermia, DNAJA4 deficiency further augmented the expression of CLU and p-ERK. CLU deficiency enhanced the p-ERK expression. Hyperthermia-induced CLU and p-ERK exerted protective roles mainly through inhibiting apoptosis and maintaining cell cycle, respectively. CONCLUSIONS: In keratinocytes, CLU and p-ERK are induced by hyperthermia, an effect which can be further enhanced by DNAJA4 deficiency. CLU deficiency also increases p-ERK expression. Both CLU and p-ERK are critical protective factors of human keratinocytes from hyperthermia-induced injury.


Asunto(s)
Clusterina , Hipertermia Inducida , Apoptosis , Clusterina/genética , Proteínas del Choque Térmico HSP40 , Humanos , Hipertermia , Queratinocitos , Factores Protectores
10.
Skin Res Technol ; 24(3): 379-385, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29377397

RESUMEN

BACKGROUND: Skin imaging analysis, acting as a supplement to noninvasive bioengineering devices, has been widely used in medical cosmetology and cosmetic product evaluation. The main aim of this study is to assess the differences and correlations in measuring skin spots, wrinkles, vascular features, porphyrin, and pore between two commercially available image analysis software. MATERIALS AND METHODS: Seventy healthy women were included in the study. Before taking pictures, the dermatologist evaluated subjects' skin conditions. Test sites included the forehead, cheek, and periorbital skin. A 2 × 2 cm cardboard was used to make a mark on the skin surface. Pictures were taken using VISIA® under three kinds light conditions and analyzed using VISIA® and IPP® respectively. RESULTS: (1) Skin pore, red area, ultraviolet spot, brown spot, porphyrin, and wrinkle measured with VISIA® were correlated with those measured with IPP® (P < .01). (2) Spot, wrinkle, fine line, brown spot, and red area analyzed with VISIA® were correlated with age on the forehead and periorbital skin (P < .05). L-value, Crow's feet, ultraviolet spot, brown spot, and red area analyzed with IPP® were correlated with age on the periorbital skin (P < .05). (3) L-value, spot, wrinkle, fine line, porphyrin, red area, and pore analyzed with VISIA® and IPP® showed correlations with the subjective evaluation scores (P < .05). CONCLUSIONS: VISIA® and IPP® showed acceptable correlation in measuring various skin conditions. VISIA® showed a high sensibility when measured on the forehead skin. IPP® is available as an alternative software program to evaluate skin features.


Asunto(s)
Hiperpigmentación/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Envejecimiento de la Piel , Piel/diagnóstico por imagen , Programas Informáticos , Adulto , Femenino , Humanos , Modelos Lineales , Persona de Mediana Edad , Adulto Joven
11.
J Anim Physiol Anim Nutr (Berl) ; 102(3): 611-619, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29095532

RESUMEN

The objective of this study was to evaluate the effects of dietary crude protein (CP) levels and 2-methylbutyrate (MB) supplementation on ruminal fermentation, bacterial populations, microbial enzyme activity and urinary excretion of purine derivatives (PD) in Simmental steers. Eight ruminally cannulated Simmental steers, averaging 18 months of age and 465 ± 8.6 kg of body weight (BW), were used in a replicated 4 × 4 Latin square design by a 2 × 2 factorial arrangement. Low protein (98.5 g CP/kg dry matter [LP] or high protein (128.7 g CP/kg dry matter [HP]) diets were fed with MB supplementation (0 g [MB-] or 16.8 g steer-1  day-1 [MB+]). Steers were fed a total mixed ration with dietary corn straw to concentrate ratio of 50:50 (dry matter [DM] basis). The CP × MB interaction was observed for ruminal total VFA, molar proportions of acetate and propionate, acetate to propionate ratio, ammonia-N, effective degradability of neutral detergent fibre (NDF) and CP, microbial enzyme activity, bacterial populations and total PD excretion (p < .05). Ruminal pH decreased (p < .05), but ruminal total VFA concentration increased (p < .05) with increasing dietary CP level or MB supplementation. Acetate molar proportion increased (p = .043) with MB supplementation, but was not affected by dietary CP level. Propionate molar proportion decreased (p < .05) with increasing dietary CP level or MB supplementation. Consequently, acetate-to-propionate ratio increased (p = .001) with MB supplementation, but was not affected by dietary CP level. Ruminal ammonia-N content increased (p = .034) with increasing dietary CP level, but decreased (p = .012) with MB supplementation. The effective degradability of NDF and CP increased (p < .05) with increasing dietary CP level or MB supplementation. Microbial enzyme activity, bacterial populations and total PD excretion also increased (p < .05) with increasing dietary CP level or MB supplementation. The results indicated that ruminal fermentation, nutrient degradability, microbial enzyme activity, ruminal bacterial populations and microbial protein synthesis improved with increasing dietary CP level or MB supplementation in steers.


Asunto(s)
Butiratos/administración & dosificación , Bovinos/fisiología , Proteínas en la Dieta/administración & dosificación , Purinas/metabolismo , Rumen/fisiología , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Bovinos/orina , Dieta/veterinaria , Fermentación , Masculino , Valor Nutritivo , Purinas/orina , Rumen/microbiología
12.
J Anim Physiol Anim Nutr (Berl) ; 102(4): 901-909, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29717516

RESUMEN

This study evaluated the effects of dietary concentrate levels and 2-methylbutyrate (2MB) supplementation on performance, ruminal fermentation, bacteria abundance, microbial enzyme activity and urinary excretion of purine derivatives (PD) in steers. Eight ruminally cannulated Simmental steers (12 months of age; 389 ± 3.7 kg of body weight) were used in a replicated 4 × 4 Latin square design with a 2 × 2 factorial arrangement. Moderate-concentrate (400 g/kg diet [MC]) or high-concentrate (600 g/kg diet [HC]) diets were fed with or without 2MB (0 g/day [2MB-] or 15.0 g/day [2MB+]). Dry matter intake and average daily gain increased, but feed conversion ratio decreased with the HC diet or 2MB supplementation. Ruminal pH decreased, but total volatile fatty acid increased with the HC diet or 2MB supplementation. Molar proportion of acetate and acetate-to-propionate ratio decreased with the HC diet, but increased with 2MB supplementation. Propionate molar proportion and ruminal NH3 -N content increased with the HC diet, but decreased with 2MB supplementation. Neutral detergent fibre degradability decreased with the HC diet, but increased with 2MB supplementation. Crude protein degradability increased with the HC diet or 2MB supplementation. Abundance of Ruminococcus albus, Ruminococcus flavefaciens, Fibrobacter succinogenes and Bufyrivibrio fibrisolvens as well as activities of carboxymethyl cellulase, cellobiase, xylanase and pectinase decreased with the HC diet, but increased with 2MB supplementation. However, abundance of Prevotella ruminicola and Ruminobacter amylophilus as well as activities of α-amylase and protease increased with the HC diet or 2MB supplementation. Total PD excretion also increased with the HC diet or 2MB supplementation. The results suggested that growth performance, ruminal fermentation, CP degradability and total PD excretion increased with increasing dietary concentrate level from 40% to 60% or 2MB supplementation. The observed diet × 2MB interaction indicated that supplementation of 2MB was more efficacious for improving growth performance, ruminal fermentation and total PD excretion with promoted ruminal bacteria abundance and enzyme activity in the MC diet than in the HC diet.


Asunto(s)
Butiratos/farmacología , Dieta/veterinaria , Fermentación/efectos de los fármacos , Purinas/orina , Rumen/metabolismo , Alimentación Animal/análisis , Animales , Bacterias , Butiratos/administración & dosificación , Bovinos , Digestión , Fermentación/fisiología , Concentración de Iones de Hidrógeno , Masculino , Rumen/microbiología
13.
Phys Rev Lett ; 118(16): 165001, 2017 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-28474938

RESUMEN

We investigate a new laser-driven spherically convergent plasma fusion scheme (SCPF) that can produce thermonuclear neutrons stably and efficiently. In the SCPF scheme, laser beams of nanosecond pulse duration and 10^{14}-10^{15} W/cm^{2} intensity uniformly irradiate the fuel layer lined inside a spherical hohlraum. The fuel layer is ablated and heated to expand inwards. Eventually, the hot fuel plasmas converge, collide, merge, and stagnate at the central region, converting most of their kinetic energy to internal energy, forming a thermonuclear fusion fireball. With the assumptions of steady ablation and adiabatic expansion, we theoretically predict the neutron yield Y_{n} to be related to the laser energy E_{L}, the hohlraum radius R_{h}, and the pulse duration τ through a scaling law of Y_{n}∝(E_{L}/R_{h}^{1.2}τ^{0.2})^{2.5}. We have done experiments at the ShengGuangIII-prototype facility to demonstrate the principle of the SCPF scheme. Some important implications are discussed.

14.
Nanoscale ; 15(10): 4870-4881, 2023 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-36779233

RESUMEN

Radiation-induced heterogeneous damage is the single largest source of failures seen in structural components in nuclear power reactors. Single crystal materials without grain boundaries, show considerable promise for overcoming this problem. In this work, such heterogeneous damage was further overcome in NixFe1-x single crystal alloys via a simple strategy of fine-tuning the composition. [001] NixFe1-x (x = 0, 0.38 and 0.62 at%) single crystals prepared using the Bridgman method were irradiated over a wide fluence range (4 × 1013 to 4 × 1015 ions per cm2). The irradiation-induced defect evolution was studied using Rutherford backscattering/channeling spectrometry, Monte Carlo simulations, transmission electron microscopy and nanoindentation. The results indicate an increased radiation tolerance of Ni0.38Fe0.62 compared to pure Ni and Ni0.62Fe0.38. The structural analysis performed by transmission electron microscopy revealed that defects tend to agglomerate at one place in Ni and Ni0.62Fe0.38, while in Ni0.38Fe0.62 no defect accumulation zone (characteristic damage peak) has been captured either at low or high fluence. Moreover, we found that the hardness change with the increase of Fe content is due to different arrangements of Fe atoms in the crystal structure, which influences the obtained mechanical properties of NixFe1-x in the pristine state and after ion implantation.

15.
Artículo en Zh | MEDLINE | ID: mdl-37899561

RESUMEN

Objective: To explore the effects of low position lateral supramalleolar flap carrying periosteum and proximal leg propeller flap in relay repair of electric burn wounds of forefoot. Methods: A retrospective observational study was conducted. From January 2019 to January 2022, 12 patients with electric burn wounds of forefoot meeting the inclusion criteria were admitted to the Sixth Hospital of Shanxi Medical University, including 10 males and 2 females, aged 23-65 years. After debridement, the wound with an area of 6.0 cm×3.0 cm to 15.0 cm×7.0 cm was repaired with the lateral supramalleolar flap carrying part of the periosteum of the distal tibia and fibula with the rotation point moved down to the front of the ankle joint. The area of the cutted flap was 6.5 cm×3.5 cm-15.5 cm×7.5 cm. At the same stage, the donor site wound of lateral supramalleolar flap was repaired with peroneal artery or superficial peroneal artery perforator propeller flap in relay, with the relay flap area of 3.0 cm×1.5 cm-15.0 cm×4.0 cm. After operation, the survival of the lateral supramalleolar flap and relay flap, and the wound healing of the relay flap donor site were observed. During follow-up, the shapes of the lateral supramalleolar flap and its donor site were observed. Results: After operation, one patient developed secondary blisters in the superficial skin distal to the lateral supramalleolar flap, which healed after dressing change, and the lateral supramalleolar flap and relay flaps survived well in the other patients; the donor site wound of the relay flap healed well. During follow-up of 12-18 months, the lateral supramalleolar flaps were in good shape and not bloated, with only linear scar left in the donor site of the flap. Conclusions: The low position lateral supramalleolar flap carrying periosteum can repair electric burn wounds of forefoot with advantages including reliable blood supply, low rotation point, and better repair effects. The use of relay flap to repair the donor site of lateral supramalleolar flap can reduce the damage to the appearance and function of the donor site.


Asunto(s)
Quemaduras por Electricidad , Colgajo Perforante , Procedimientos de Cirugía Plástica , Traumatismos de los Tejidos Blandos , Femenino , Humanos , Masculino , Quemaduras por Electricidad/cirugía , Pierna/cirugía , Periostio/cirugía , Trasplante de Piel , Traumatismos de los Tejidos Blandos/cirugía , Resultado del Tratamiento , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano
17.
Animal ; 14(10): 2091-2099, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32340650

RESUMEN

Se can enhance lactation performance by improving nutrient utilization and antioxidant status. However, sodium selenite (SS) can be reduced to non-absorbable elemental Se in the rumen, thereby reducing the intestinal availability of Se. The study investigated the impacts of SS and coated SS (CSS) supplementation on lactation performance, nutrient digestibility, ruminal fermentation and microbiota in dairy cows. Sixty multiparous Holstein dairy cows were blocked by parity, daily milk yield and days in milk and randomly assigned to five treatments: control, SS addition (0.3 mg Se/kg DM as SS addition) or CSS addition (0.1, 0.2 and 0.3 mg Se/kg DM as CSS addition for low CSS (LCSS), medium CSS (MCSS) and high CSS (HCSS), respectively). Experiment period was 110 days with 20 days of adaptation and 90 days of sample collection. Dry matter intake was higher for MCSS and HCSS compared with control. Yields of milk, milk fat and milk protein and feed efficiency were higher for MCSS and HCSS than for control, SS and LCSS. Digestibility of DM and organic matter was highest for CSS addition, followed by SS addition and then control. Digestibility of CP was higher for MCSS and HCSS than for control, SS and LCSS. Higher digestibility of ether extract, NDF and ADF was observed for SS or CSS addition. Ruminal pH decreased with dietary Se addition. Acetate to propionate ratio and ammonia N were lower, and total volatile fatty acids (VFAs) concentration was greater for SS, MCSS and HCSS than control. Ruminal H ion concentration was highest for MCSS and HCSS and lowest for control. Activities of cellobiase, carboxymethyl-cellulase, xylanase and protease and copies of total bacteria, fungi, Ruminococcus flavefaciens, Fibrobacter succinogenes and Ruminococcus amylophilus increased with SS or CSS addition. Activity of α-amylase, copies of protozoa, Ruminococcus albus and Butyrivibrio fibrisolvens and serum glucose, total protein, albumin and glutathione peroxidase were higher for SS, MCSS and HCSS than for control and LCSS. Dietary SS or CSS supplementation elevated blood Se concentration and total antioxidant capacity activity. The data implied that milk yield was elevated due to the increase in total tract nutrient digestibility, total VFA concentration and microorganism population with 0.2 or 0.3 mg Se/kg DM from CSS supplementation in dairy cows. Compared with SS, HCSS addition was more efficient in promoting lactation performance of dairy cows.


Asunto(s)
Fermentación , Lactancia , Rumen , Selenito de Sodio , Animales , Bovinos , Femenino , Embarazo , Alimentación Animal/análisis , Dieta/veterinaria , Suplementos Dietéticos , Digestión , Fibrobacter , Nutrientes , Rumen/metabolismo , Ruminococcus , Selenito de Sodio/metabolismo
18.
Animal ; 14(6): 1176-1183, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31840620

RESUMEN

The combined addition of branched-chain volatile fatty acids (BCVFAs) and folic acid (FA) could improve growth performance and nutrient utilization by stimulating ruminal microbial growth and enzyme activity. This study was conducted to evaluate the effects of BCVFA and FA addition on growth performance, ruminal fermentation, nutrient digestibility, microbial enzyme activity, microflora and excretion of urinary purine derivatives (PDs) in calves. Thirty-six Chinese Holstein weaned calves (60 ± 5.4 days of age and 107 ± 4.7 kg of BW) were assigned to one of four groups in a randomized block design. Treatments were control (without additives), FA (with 10 mg FA/kg dietary DM), BCVFA (with 5 g BCVFA/kg dietary DM) and the combined addition of FA and BCVFA (10 mg/kg DM of FA and 5 g/kg DM of BCVFA). Supplements were hand-mixed into the top one-third of total mixed ration. Dietary concentrate to maize silage ratio was 50 : 50 on a DM basis. Dietary BCVFA or FA addition did not affect dry matter intake but increased average daily gain (ADG) and feed conversion efficiency. Ruminal pH and ammonia N were lower, and total volatile fatty acids (VFAs) concentration was higher for BCVFA or FA addition than for control. Dietary BCVFA or FA addition did not affect acetate proportion but decreased propionate proportion and increased acetate to propionate ratio. Total tract digestibility of DM, organic matter, CP and NDF was higher for BCVFA or FA addition than for control. Dietary BCVFA or FA addition increased activity of carboxymethyl cellulase and cellobiase, population of total bacteria, fungi, Ruminococcus albus, R. flavefaciens, Fibrobacter succinogenes and Prevotella ruminicola as well as total PD excretion. Ruminal xylanase, pectinase and protease activity and Butyrivibrio fibrisolvens population were increased by BCVFA addition, whereas population of protozoa and methanogens was increased by FA addition. The BCVFA × FA interaction was significant for acetate to propionate ratio, cellobiase activity and total PD excretion, and these variables increased more with FA addition in diet without BCVFA than in diet with BCVFA. The data indicated that supplementation with BCVFA or FA increased ADG, nutrient digestibility, ruminal total VFA concentration and microbial protein synthesis by stimulating ruminal microbial growth and enzyme activity in calves.


Asunto(s)
Bovinos/fisiología , Celulasa/metabolismo , Suplementos Dietéticos/análisis , Ácidos Grasos Volátiles/administración & dosificación , Ácido Fólico/administración & dosificación , Microbioma Gastrointestinal/efectos de los fármacos , Amoníaco/metabolismo , Animales , Bovinos/crecimiento & desarrollo , Bovinos/microbiología , Dieta/veterinaria , Digestión/efectos de los fármacos , Femenino , Fermentación , Nutrientes/metabolismo , Rumen/metabolismo , Rumen/microbiología , Ensilaje/análisis , Destete
19.
Animal ; 14(12): 2535-2542, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32580813

RESUMEN

Guanidinoacetic acid (GAA) can improve the growth performance of bulls. This study investigated the influences of GAA addition on growth, nutrient digestion, ruminal fermentation and serum metabolites in bulls. Forty-eight Angus bulls were randomly allocated to experimental treatments, that is, control, low-GAA (LGAA), medium-GAA (MGAA) and high-GAA (HGAA), with GAA supplementation at 0, 0.3, 0.6 and 0.9 g/kg DM, respectively. Bulls were fed a basal diet containing 500 g/kg DM concentrate and 500 g/kg DM roughage. The experimental period was 104 days, with 14 days for adaptation and 90 days for data collection. Bulls in the MGAA and HGAA groups had higher DM intake and average daily gain than bulls in the LGAA and control groups. The feed conversion ratio was lowest in MGAA and highest in the control. Bulls receiving 0.9 g/kg DM GAA addition had higher digestibility of DM, organic matter, NDF and ADF than bulls in other groups. The digestibility of CP was higher for HGAA than for LGAA and control. The ruminal pH was lower for MGAA, and the total volatile fatty acid concentration was greater for MGAA and HGAA than for the control. The acetate proportion and acetate-to-propionate ratio were lower for MGAA than for LGAA and control. The propionate proportion was higher for MGAA than for control. Bulls receiving GAA addition showed decreased ruminal ammonia N. Bulls in MGAA and HGAA had higher cellobiase, pectinase and protease activities and Butyrivibrio fibrisolvens, Prevotella ruminicola and Ruminobacter amylophilus populations than bulls in LGAA and control. However, the total protozoan population was lower for MGAA and HGAA than for LGAA and control. The total bacterial and Ruminococcus flavefaciens populations increased with GAA addition. The blood level of creatine was higher for HGAA, and the activity of l-arginine glycine amidine transferase was lower for MGAA and HGAA, than for control. The blood activity of guanidine acetate N-methyltransferase and the level of folate decreased in the GAA addition groups. The results indicated that dietary addition of 0.6 or 0.9 g/kg DM GAA improved growth performance, nutrient digestion and ruminal fermentation in bulls.


Asunto(s)
Digestión , Rumen , Alimentación Animal/análisis , Animales , Bovinos , Dieta/veterinaria , Suplementos Dietéticos , Fermentación , Glicina/análogos & derivados , Masculino , Nutrientes , Rumen/metabolismo , Ruminococcus , Succinivibrionaceae
20.
Urol Int ; 83(3): 337-41, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19829037

RESUMEN

INTRODUCTION: Urological complications after kidney transplantation may lead to graft loss. In this study, we retrospectively reviewed urological complications in 1,223 kidney transplantations that were performed at our institution. MATERIALS AND METHODS: The occurrence of urological complications such as urine leakage, ureteral obstruction and vesicoureteral reflux (VUR) according to the different way of urinary tract reconstruction, ureteroneocystostomy (U-C) and ureteroureterostomy (U-U), was studied. RESULTS: Urological complications were encountered in 92 (7.5%) cases, including urine leakage (n = 43, 3.5%), ureteral obstruction (n = 35, 2.9%) and VUR (n = 14, 1.1%). 75 cases (7.9%) were in the U-C group and 17 cases (6.2%) in the U-U group. 91 recipients were successfully treated, and 1 patient lost the graft due to kidney pelvis and ureteral necrosis. There was no recipient loss due to these complications. For recipients with urological complications, the 1- and 3-year survival rates were 90 and 88% for recipients and 87 and 82% for grafts, respectively. CONCLUSIONS: After U-U, the same number of overall incidences of urological complications is observed as after U-C; however, a decrease in the number of incidences of urine leakage is apparent. Therefore, U-U is a good first option with a greater success rate of resolving ureteral stenosis with endourology and no risk of VUR.


Asunto(s)
Trasplante de Riñón/efectos adversos , Trasplante de Riñón/métodos , Enfermedades Urológicas/etiología , Adulto , Femenino , Humanos , Trasplante de Riñón/estadística & datos numéricos , Masculino , Estudios Retrospectivos , Enfermedades Urológicas/epidemiología
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