Over the past few decades,genetic selection and refined nutritional management have extensively been used to increase the growth rate and lean meat production of livestock.However,the rapid growth rates of modern bree...Over the past few decades,genetic selection and refined nutritional management have extensively been used to increase the growth rate and lean meat production of livestock.However,the rapid growth rates of modern breeds are often accompanied by a reduction in intramuscular fat deposition and increased occurrences of muscle abnor‑malities,impairing meat quality and processing functionality.Early stages of animal development set the long‑term growth trajectory of offspring.However,due to the seasonal reproductive cycles of ruminant livestock,gestational nutrient deficiencies caused by seasonal variations,frequent droughts,and unfavorable geological locations nega‑tively affect fetal development and their subsequent production efficiency and meat quality.Therefore,enrolling live‑stock in nutritional intervention strategies during gestation is effective for improving the body composition and meat quality of the offspring at harvest.These crucial early developmental stages include embryonic,fetal,and postnatal stages,which have stage‑specific effects on subsequent offspring development,body composition,and meat quality.This review summarizes contemporary research in the embryonic,fetal,and neonatal development,and the impacts of maternal nutrition on the early development and programming effects on the long‑term growth performance of livestock.Understanding the developmental and metabolic characteristics of skeletal muscle,adipose,and fibrotic tissues will facilitate the development of stage‑specific nutritional management strategies to optimize production efficiency and meat quality.展开更多
Intestinal stem cells(ISCs)initiate intestinal epithelial regeneration and tumorigenesis,and they experi-ence rapid refilling upon various injuries for epithelial repair as well as tumor reoccurrence.It is crucial to ...Intestinal stem cells(ISCs)initiate intestinal epithelial regeneration and tumorigenesis,and they experi-ence rapid refilling upon various injuries for epithelial repair as well as tumor reoccurrence.It is crucial to reveal the mechanism underlying such plasticity for intestinal health.Recent studies have found that metabolic pathways control stem cell fate in homeostasis,but the role of metabolism in the regeneration of ISCs after damage has not been clarified.Here,we find that in a human colorectal cancer dataset,miR-29a and b(miR-29a/b)are metabolic regulators highly associated with intestinal tumorigenesis and worse prognostic value of radiotherapy.We also show that these two microRNAs are required for intesti-nal stemness maintenance in mice,and their expression is induced in regenerated ISCs after irradiation injury,resulting in skewed ISC fate from differentiation towards self-renewal.This upregulation of miR-29a/b expression in ISCs leads to suppression of fatty acid oxidation(FAO)and depression of oxidative phosphorylation,which in turn controls the balance between self-renewal and differentiation of ISCs.Deletion of miR-29a/b prevents these effects and thus impairs ISC-mediated epithelial recovery.Finally,we filter the potential targets of miR-29a/b and identify Hnf4g,a transcription factor,that drives this metabolic reprogramming through regulating FAO-related enzymes.Our work discovers an impor-tant metabolic mechanism of ISC-mediated regeneration and potentially pave the way for more targeted and effective therapeutic strategies for intestinal repair as well as tumor treatment.展开更多
Background: Marbling, or intramuscular fat, is an important factor contributing to the palatability of beef. Vitamin A, through its active metabolite, retinoic acid, promotes the formation of new fat cells(adipogenesi...Background: Marbling, or intramuscular fat, is an important factor contributing to the palatability of beef. Vitamin A, through its active metabolite, retinoic acid, promotes the formation of new fat cells(adipogenesis). As intramuscular adipogenesis is active during the neonatal stage, we hypothesized that vitamin A administration during the neonatal stage would enhance intramuscular adipogenesis and marbling.Methods: Angus steer calves(n = 30), in a completely randomized design, were randomly allotted to three treatment groups at birth, receiving 0, 150,000, or 300,000 IU of vitamin A at both birth and one month of age.A biopsy of the biceps femoris muscle was collected at two months of age. After weaning at 210 d of age, steers were fed a backgrounding diet in a feedlot until 308 d of age, when they were transitioned to a high concentrate finishing diet and implanted with trenbolone/estradiol/tylosin mixture. Steers were harvested at an average of 438 d of age. All diets were formulated to meet nutrient requirements.Results: Weaning weight and weight during the backgrounding phase were linearly increased(P < 0.05) by vitamin A level, though no difference in body weight was observed at harvest. Intramuscular fat of steers at 308 d of age, measured by ultrasound, quadratically increased(P < 0.05) with vitamin A level from 4.0±0.26 % to 4.9±0.26 %.Similarly, carcass marbling score in the ribeye quadratically increased(P < 0.05).Conclusion: Administration of vitamin A at birth increased weaning weight and enhanced marbling fat development.Thus, vitamin A administration provides a practical method for increasing marbling and early growth of beef cattle.展开更多
Background: Vitamin A and its metabolite,retinoic acid(RA),are important regulators of cell differentiation and organ morphogenesis.Its impact on beef cattle muscle growth remains undefined.Method: Angus steer calves ...Background: Vitamin A and its metabolite,retinoic acid(RA),are important regulators of cell differentiation and organ morphogenesis.Its impact on beef cattle muscle growth remains undefined.Method: Angus steer calves were administrated with 0(control) or 150,000 IU vitamin A(retinyl palmitate in glycerol,i.m.) per calf at birth and 1 month of age.At 2 months of age,a biopsy of the Biceps femoris muscle was obtained to analyze the immediate effects of vitamin A injection on myogenic capacity of muscle cells.The resulting steers were harvested at 14 months of age.Results: Vitamin A administration increased cattle growth at 2 months.At 2 months of age,Vitamin A increased PAX7 positive satellite cells and the expression of myogenic marker genes including PAX7,MYF5,MYOD and MYOG.Muscle derived mononuclear cells were further isolated and induced myogenesis in vitro.More myotubes and a higher degree of myogenesis was observed in vitamin A groups.Consistently,vitamin A increased Latissimus dorsi(LD) muscle fiber size at harvest.In addition,vitamin A increased the ratio of oxidative type I and type IIA fibers and reduced the glycolic type IIX fibers.Furthermore,we found that RA,a key bioactive metabolite of vitamin A,activated PPARGC1 A promoter,which explains the upregulated expression of PPARGC1 A in skeletal muscle.Conclusion: Vitamin A administration to neonatal calves enhanced postnatal muscle growth by promoting myogenesis and increasing satellite cell density,accompanied with a shift to oxidative muscle fibers.展开更多
Here we investigated the possible roles of oxidative stress in the formation of decreased thermotaxis to cultivation temperature in lead(Pb)-exposed nematodes Caenorhabditis elagans.Exposure to Pb at the examined conc...Here we investigated the possible roles of oxidative stress in the formation of decreased thermotaxis to cultivation temperature in lead(Pb)-exposed nematodes Caenorhabditis elagans.Exposure to Pb at the examined concentrations decreased thermotaxis behaviors,and induced severe deficits in the structural properties of AFD sensory neurons.Meanwhile,Pb exposure caused the induction of severe oxidative damage,reactive oxygen species(ROS)production,and mitochondrial dysfunction in young adults.Moreover,pre-treatment with the antioxidants dimethyl sulfoxide(DMSO),ascorbate and N-acetyl-L-cysteine(NAC),used to inhibit both the ROS elevation and the mitochondrial dysfunction caused by Pb exposure,at the L2-1arval stage prevented the induction of oxidative damage and the formation of severe deficits in thermotaxis and structural properties of AFD sensory neurons in Pb-exposed young adults.Therefore,the formation of oxidative stress caused by Pb exposure may be due to both the induction of ROS elevation and damage to mitochondrial function,and oxidative stress may play a key role in inducing the neurotoxic effects on the structures and function of AFD sensory neurons in Pb-exposed nematodes.展开更多
Although IL-12 plays a critical role in priming Th1 and cytotoxic T lymphocyte(CTL) responses, Toll-like receptor(TLR) signaling only induces low amounts of IL-12 in dendritic cells and macrophages, implying the exist...Although IL-12 plays a critical role in priming Th1 and cytotoxic T lymphocyte(CTL) responses, Toll-like receptor(TLR) signaling only induces low amounts of IL-12 in dendritic cells and macrophages, implying the existence of stringent regulatory mechanisms. In this study, we sought to uncover the mechanisms underlying TLR-induced IL-12 expression and the Th1 response. By systemic screening, we identified a number of protein kinases involved in the regulation of TLRinduced IL-12 expression. In particular, PI3 K, ERK, and m TOR play critical roles in the TLR-induced Th1 response by regulating IL-12 and IL-10 production in innate immune cells. Moreover, we identified c-fos as a key molecule that mediates m TOR-regulated IL-12 and IL-10 expression in TLR signaling. Mechanistically, m TOR plays a crucial role in c-fos expression, thereby modulating NFκB binding to promoters of IL-12 and IL-10. By controlling the expression of a special innate gene program, m TOR can specifically regulate the TLR-induced T cell response in vivo. Furthermore, blockade of m TOR by rapamycin efficiently boosted TLR-induced antigen-specific T and B cell responses to HBV and HCV vaccines. Taken together, these results reveal a novel mechanism through which m TOR regulates TLR-induced IL-12 and IL-10 production, contributing new insights for strategies to improve vaccine efficacy.展开更多
980 high-strength steel has been widely used in marine engineering structures due to its high strength and toughness.However,it is easily affected by the harsh environmental conditions(such as the presence of sulfate-...980 high-strength steel has been widely used in marine engineering structures due to its high strength and toughness.However,it is easily affected by the harsh environmental conditions(such as the presence of sulfate-reducing bacteria,SRB),leading to the risk of stress corrosion cracking(SCC).In this paper,the effects of SRB and its metabolites on hydrogen permeation and SCC mechanism of 980 steel in seawater solution were investigated by slow strain rate tensile test,scanning electron microscope,Xray energy spectroscopy,Raman spectroscopy and Devanathan-Stachurski double electrolytic cell.Results demonstrated that the SCC susceptibility of 980 steel was promoted in the presence of SRB,which was related to the cultivation time of the bacteria.When SRB were cultivated for 3 d and 6 d,the SCC mechanism was controlled by hydrogen-induced cracking(HIC);while the cultivation time extended to 11 d,the SCC of 980 steel was under the combined effect of the anodic dissolution(AD) and HIC mechanism.When cultivated for 16 d,the SCC of 980 steel was caused by the dominant AD.Both the SRB accelerated hydrogen permeation under cathodic depolarization process and SRB assisted AD(pitting corrosion)played an enhancing role in promoting SCC susceptibility of 980 steel.展开更多
AIM:To investigate the effect of side-stream smoking on gut microflora composition,intestinal inflammation and expression of tight junction proteins.METHODS:C57BL/6 mice were exposed to side-stream cigarette smoking f...AIM:To investigate the effect of side-stream smoking on gut microflora composition,intestinal inflammation and expression of tight junction proteins.METHODS:C57BL/6 mice were exposed to side-stream cigarette smoking for one hour daily over eight weeks.Cecal contents were collected for microbial composition analysis.Large intestine was collected for immunoblotting and quantitative reverse transcriptase polymerase chain reaction analyses of the inflammatory pathway and tight junction proteins.RESULTS:Side-stream smoking induced significant changes in the gut microbiota with increased mouse intestinal bacteria,Clostridium but decreased Fermicutes(Lactoccoci and Ruminococcus),Enterobacteriaceae family and Segmented filamentous baceteria compared to the control mice.Meanwhile,side-stream smoking inhibited the nuclear factor-κB pathway with reduced phosphorylation of p65 and IκBα,accompanied with unchanged mRNA expression of tumor necrosis factor-α or interleukin-6.The contents of tight junction proteins,claudin3 and ZO2 were up-regulated in the large intestine of mice exposed side-stream smoking.In addition,side-stream smoking increased c-Jun N-terminal kinase and p38 MAPK kinase signaling,while inhibiting AMPactivated protein kinase in the large intestine.CONCLUSION:Side-stream smoking altered gut microflora composition and reduced the inflammatory response,which was associated with increased expression of tight junction proteins.展开更多
Lycium barbarum residue(LBR),a by-product of L.barbarum processing,is packed with bioactive components and can be potentially utilized as a feed additive in animal husbandry.However,the fundamental understanding of it...Lycium barbarum residue(LBR),a by-product of L.barbarum processing,is packed with bioactive components and can be potentially utilized as a feed additive in animal husbandry.However,the fundamental understanding of its effectiveness on livestock animals is still lacking,particularly in ruminants.To explore the effects of LBR on the growth performance,rumen fermentation parameters,ruminal microbes and metabolites of Tan sheep,sixteen fattening rams(aged 4 mon)were fed a basal diet(CON,n=8)or a basal diet supplemented with 5%LBR(LBR,n=8).The experiment lasted for 70 d,with 10 d adaptation period and 60 d treatment period.The results showed that the LBR enhanced the average daily feed intake,average daily gain(P<0.05),and ruminal total volatile fatty acids(P<0.01)while decreasing ammonia-nitrogen concentration and rumen pH value(P<0.05).Additionally,the LBR improved the relative abundances of Prevotella,Succiniclasticum,Ruminococcus,Coprococcus,Selenomonas,and Butyrivibrio(P<0.05)and reduced the relative abundances of Oscillospira and Succinivibrio(P<0.05).The LBR altered the ruminal metabolome(P<0.01)by increasing the abundances of ruminal metabolites involved in amino acids(e.g.,L-proline,L-phenylalanine,L-lysine,and L-tyrosine),pyrimidine metabolism(e.g.,uridine,uracil,and thymidine),and microbial protein synthesis(e.g.,xanthine and hypoxanthine).In conclusion,LBR had positive effects on the growth rate of Tan sheep as well as on rumen fermentation parameters,rumen microbiome and rumen metabolome.展开更多
[Objectives] The research aimed to explore the prevention and control effects of icaritin( ICT) on fruit fly model of Alzheimer's disease( AD),and provide theoretical basis for the development and application of n...[Objectives] The research aimed to explore the prevention and control effects of icaritin( ICT) on fruit fly model of Alzheimer's disease( AD),and provide theoretical basis for the development and application of new clinical medicine. [Methods]AD fruit fly model was established,and ICT was used to respectively intervene normal fruit fly and the fly transforming Aβ42. The test was divided into four groups:normal control group( Norm. group,feeding normal food solvent control),ICT intervention group of normal fruit fly( Norm. + ICT group,0. 04 mg/m L of ICT intervention),model control group( Aβ42 group,feeding normal feed solvent control) and model feeding ICT group( Aβ42 + ICT group,0. 04 mg/m L of ICT intervention). HE dyeing of fruit fly brain tissue,climbing ability,lifetime were respectively detected at whole level,and ATP,SOD and MDA contents of brain tissue were measured. [Results]Compared with AD fruit fly,there was no obvious hollow in fruit fly brain tissue slice of normal control group with the same age. Climbing ability,average lifetime,ATP,SOD and MDA contents in AD fruit fly group feeding ICT in old age were significantly improved. Normal control group was compared with normal control feeding ICT group,climbing ability,ATP,SOD and MDA contents had no statistical difference,and average lifetime was improved in normal feeding ICT group. [Conclusions]ICT could improve the behavior and lifetime of AD fruit fly,increase ATP content of brain tissue,enhance the ability to scavenge free radicals and resist lipid peroxidation,and protect AD fruit fly.展开更多
The rising global incidence of diabetes mellitus(DM)and hyperuricemia presents a growing challenge to public health systems worldwide.Urate transporter-1(URAT1),a key renal urate transporter,has emerged as a promising...The rising global incidence of diabetes mellitus(DM)and hyperuricemia presents a growing challenge to public health systems worldwide.Urate transporter-1(URAT1),a key renal urate transporter,has emerged as a promising therapeutic target for managing DM and its associated complications.Growing evidence suggests that URAT1’s role in metabolic disorders extends beyond its function in the kidney.Specifically,URAT1 can influence uric acid metabolism in multiple tissues including neural,hepatic,vascular smooth muscle,cardiac,and adipose tissue,thereby contributing to insulin resistance,inflammation,and end-organ damage.In this review,we comprehensively examine the extra-renal functions of URAT1,focusing on its roles in the hematopoietic system,heart,liver,adipose tissue,and vascular endothelium in the context of DM.This analysis highlights the multi-organ mechanisms through which URAT1 exerts its effects,offering valuable insights into its potential as a therapeutic target for this complex sys-temic metabolic disorder.展开更多
Experiments were designed to simulate the corrosion of a low-carbon steel exposed to a marine splash zone. The composition and morphology of the rust were investigated using Raman spectroscopy, X-ray photoelectron spe...Experiments were designed to simulate the corrosion of a low-carbon steel exposed to a marine splash zone. The composition and morphology of the rust were investigated using Raman spectroscopy, X-ray photoelectron spectroscopy, energy-dispersive spectrometry and scanning electron microscopy. Corrosion resistance of the rust films was demonstrated by the electrochemical impedance spectroscopy. The wettability of the steel surface was calculated from the data conceruing the wetting degree and the conductivity. The results showed that, in the initial stage, the products of the outer rust layer were mainly made up of Fe（Ⅲ） oxyhydroxide, while the main component of the inner rust layer was magnetite. With an increase in the corrosion time, the inner rust layer continuously turned into the outer rust layer. In addition, both rust layers became dense, thus playing a protective role with respect to matrix. The existence of the rust layer significantly prolonged the residence time of the seawater on the sample surface, a result that tends to improve the cathodic protection effect for steel structures exposed to marine splash zones.展开更多
The influence of temperature on calcareous deposits formed under galvanostatic polarization mode was studied. The deposition was monitored by electrochemical impedance spectrum, and a supplementary loop in Nyquist dia...The influence of temperature on calcareous deposits formed under galvanostatic polarization mode was studied. The deposition was monitored by electrochemical impedance spectrum, and a supplementary loop in Nyquist diagram at high frequency was found to be an indicator of deposits precipitation with sufficient protection at above 20 ~C. An exponential increase of protectiveness with temperature was observed, which was quantified by linear polarization resistance technique. Observation by scanning electron microscope and X-ray diffraction analyses demonstrated that the critical temperature of calcium carbonate crystal form transition ranged from 15 to 20 ℃. Calcite formed below 15 ℃, while aragonite precipitated at above 20 ℃.展开更多
A visualized investigation was carried out on the effect of the diverging angle on the bubble motion and interfacial behavior in a Venturi-type bubble generator.It was found two or three large vortexes formed in the d...A visualized investigation was carried out on the effect of the diverging angle on the bubble motion and interfacial behavior in a Venturi-type bubble generator.It was found two or three large vortexes formed in the diverging section,resulting in strong reentrant jet flow in the front of the bubbles or slugs rushing out of the throat.The jet flow in return bumps into the ongoing bubbles or slugs,leading to strong interaction between the gas and liquid phases.The diverging angle has significant influence on the reentrant flow process and the performance of the bubble generator as well.Increasing the diverging angle results in the reentrant flow moving further forward to the upstream and intensifies the interaction between the two phases.As a consequence,the breakup or collapse of bubbles becomes more violent,whereby finer bubbles are generated.As such,the reentrant flow strongly links to the performance of the Venturi channel taken as a bubble generator,and that a moderate increase in the diverging angle can improve its performance without additional increase in flow resistance like that by increasing liquid flow rate.展开更多
The risk of developing hepatocellular carcinoma(HCC) is strongly associated with hepatitis B virus infection.Hepatic angiomyolipoma(AML),a rare benign tumor,is composed of a heterogeneous mixture of adipose cells,smoo...The risk of developing hepatocellular carcinoma(HCC) is strongly associated with hepatitis B virus infection.Hepatic angiomyolipoma(AML),a rare benign tumor,is composed of a heterogeneous mixture of adipose cells,smooth muscle cells and blood vessels.Here,we report the case of a 44-year-old man who developed HCC with a concomitant hepatic AML and a cavernous hemangioma,in the absence of cirrhosis.To our knowledge,based on an extensive literature search using the www.pubmed.gov website,this is the first report of an HCC case with both concomitant AML and cavernous hemangioma at the same position in the liver.The presence of the hepatitis B surface antigen was detected,but the liver function was normal.Clinical and pathological data were collected before and during the treatment.Hepatic AML was diagnosed based on the typical histological characteristics and immunohistochemical staining,which revealed,a positive staining with a melanocytic cell-specific monoclonal antibody.There was no evidence of tuberous sclerosis complex in this patient.Although the HCC was poor- to moderately-differentiated,the characteristics of the AML and the cavernous hemangioma in this patient did not match any criteria for malignancy.Hepatectomy followed by transarterial chemoembolization treatment were effective therapeutic methods for the adjacent lesions in this patient.This case is an interesting coincidence.展开更多
基金supported by the Agriculture and Food Research Initiative Competitive Grants(No.2015-67015-23219 and 2016-68006-24634)from the USDA National Institute of Food and Agriculture.
文摘Over the past few decades,genetic selection and refined nutritional management have extensively been used to increase the growth rate and lean meat production of livestock.However,the rapid growth rates of modern breeds are often accompanied by a reduction in intramuscular fat deposition and increased occurrences of muscle abnor‑malities,impairing meat quality and processing functionality.Early stages of animal development set the long‑term growth trajectory of offspring.However,due to the seasonal reproductive cycles of ruminant livestock,gestational nutrient deficiencies caused by seasonal variations,frequent droughts,and unfavorable geological locations nega‑tively affect fetal development and their subsequent production efficiency and meat quality.Therefore,enrolling live‑stock in nutritional intervention strategies during gestation is effective for improving the body composition and meat quality of the offspring at harvest.These crucial early developmental stages include embryonic,fetal,and postnatal stages,which have stage‑specific effects on subsequent offspring development,body composition,and meat quality.This review summarizes contemporary research in the embryonic,fetal,and neonatal development,and the impacts of maternal nutrition on the early development and programming effects on the long‑term growth performance of livestock.Understanding the developmental and metabolic characteristics of skeletal muscle,adipose,and fibrotic tissues will facilitate the development of stage‑specific nutritional management strategies to optimize production efficiency and meat quality.
基金supported by the National Natural Science Foundation of China(32372247)the National Key Research and Development Program of China(2023YFF1104501)to Huiyuan Guo.
文摘Intestinal stem cells(ISCs)initiate intestinal epithelial regeneration and tumorigenesis,and they experi-ence rapid refilling upon various injuries for epithelial repair as well as tumor reoccurrence.It is crucial to reveal the mechanism underlying such plasticity for intestinal health.Recent studies have found that metabolic pathways control stem cell fate in homeostasis,but the role of metabolism in the regeneration of ISCs after damage has not been clarified.Here,we find that in a human colorectal cancer dataset,miR-29a and b(miR-29a/b)are metabolic regulators highly associated with intestinal tumorigenesis and worse prognostic value of radiotherapy.We also show that these two microRNAs are required for intesti-nal stemness maintenance in mice,and their expression is induced in regenerated ISCs after irradiation injury,resulting in skewed ISC fate from differentiation towards self-renewal.This upregulation of miR-29a/b expression in ISCs leads to suppression of fatty acid oxidation(FAO)and depression of oxidative phosphorylation,which in turn controls the balance between self-renewal and differentiation of ISCs.Deletion of miR-29a/b prevents these effects and thus impairs ISC-mediated epithelial recovery.Finally,we filter the potential targets of miR-29a/b and identify Hnf4g,a transcription factor,that drives this metabolic reprogramming through regulating FAO-related enzymes.Our work discovers an impor-tant metabolic mechanism of ISC-mediated regeneration and potentially pave the way for more targeted and effective therapeutic strategies for intestinal repair as well as tumor treatment.
基金supported by Agriculture and Food Research Initiative Competitive Grants no.2015–67015-23219 and 2016–68006-24634 from the USDA National Institute of Food and Agriculture
文摘Background: Marbling, or intramuscular fat, is an important factor contributing to the palatability of beef. Vitamin A, through its active metabolite, retinoic acid, promotes the formation of new fat cells(adipogenesis). As intramuscular adipogenesis is active during the neonatal stage, we hypothesized that vitamin A administration during the neonatal stage would enhance intramuscular adipogenesis and marbling.Methods: Angus steer calves(n = 30), in a completely randomized design, were randomly allotted to three treatment groups at birth, receiving 0, 150,000, or 300,000 IU of vitamin A at both birth and one month of age.A biopsy of the biceps femoris muscle was collected at two months of age. After weaning at 210 d of age, steers were fed a backgrounding diet in a feedlot until 308 d of age, when they were transitioned to a high concentrate finishing diet and implanted with trenbolone/estradiol/tylosin mixture. Steers were harvested at an average of 438 d of age. All diets were formulated to meet nutrient requirements.Results: Weaning weight and weight during the backgrounding phase were linearly increased(P < 0.05) by vitamin A level, though no difference in body weight was observed at harvest. Intramuscular fat of steers at 308 d of age, measured by ultrasound, quadratically increased(P < 0.05) with vitamin A level from 4.0±0.26 % to 4.9±0.26 %.Similarly, carcass marbling score in the ribeye quadratically increased(P < 0.05).Conclusion: Administration of vitamin A at birth increased weaning weight and enhanced marbling fat development.Thus, vitamin A administration provides a practical method for increasing marbling and early growth of beef cattle.
基金supported by Agriculture and Food Research Initiative Competitive Grants No.2015–67015-23219 and 2016–68006-24634 from the USDA National Institute of Food and Agriculture
文摘Background: Vitamin A and its metabolite,retinoic acid(RA),are important regulators of cell differentiation and organ morphogenesis.Its impact on beef cattle muscle growth remains undefined.Method: Angus steer calves were administrated with 0(control) or 150,000 IU vitamin A(retinyl palmitate in glycerol,i.m.) per calf at birth and 1 month of age.At 2 months of age,a biopsy of the Biceps femoris muscle was obtained to analyze the immediate effects of vitamin A injection on myogenic capacity of muscle cells.The resulting steers were harvested at 14 months of age.Results: Vitamin A administration increased cattle growth at 2 months.At 2 months of age,Vitamin A increased PAX7 positive satellite cells and the expression of myogenic marker genes including PAX7,MYF5,MYOD and MYOG.Muscle derived mononuclear cells were further isolated and induced myogenesis in vitro.More myotubes and a higher degree of myogenesis was observed in vitamin A groups.Consistently,vitamin A increased Latissimus dorsi(LD) muscle fiber size at harvest.In addition,vitamin A increased the ratio of oxidative type I and type IIA fibers and reduced the glycolic type IIX fibers.Furthermore,we found that RA,a key bioactive metabolite of vitamin A,activated PPARGC1 A promoter,which explains the upregulated expression of PPARGC1 A in skeletal muscle.Conclusion: Vitamin A administration to neonatal calves enhanced postnatal muscle growth by promoting myogenesis and increasing satellite cell density,accompanied with a shift to oxidative muscle fibers.
基金supported by the National Basic Research Program(973)of China(No.2011CB933404)the National Natural Science Foundation of China(No.30870810,81172698)Some strains used were provided by Caenorhabditis Genetics Center(funded by the NIH National Center for Research Resource,USA)
文摘Here we investigated the possible roles of oxidative stress in the formation of decreased thermotaxis to cultivation temperature in lead(Pb)-exposed nematodes Caenorhabditis elagans.Exposure to Pb at the examined concentrations decreased thermotaxis behaviors,and induced severe deficits in the structural properties of AFD sensory neurons.Meanwhile,Pb exposure caused the induction of severe oxidative damage,reactive oxygen species(ROS)production,and mitochondrial dysfunction in young adults.Moreover,pre-treatment with the antioxidants dimethyl sulfoxide(DMSO),ascorbate and N-acetyl-L-cysteine(NAC),used to inhibit both the ROS elevation and the mitochondrial dysfunction caused by Pb exposure,at the L2-1arval stage prevented the induction of oxidative damage and the formation of severe deficits in thermotaxis and structural properties of AFD sensory neurons in Pb-exposed young adults.Therefore,the formation of oxidative stress caused by Pb exposure may be due to both the induction of ROS elevation and damage to mitochondrial function,and oxidative stress may play a key role in inducing the neurotoxic effects on the structures and function of AFD sensory neurons in Pb-exposed nematodes.
基金support by National Natural Science Foundation of China grants 31070779 and 31170862 (to H.X.), 31100623 (to A.Z.) and 31270917 (to M.D.)National Key laboratory of Virology grant (2014IOV006)+3 种基金H.X. is supported by Chinese Academy of Sciences "100-talent" programNational program for returned oversea talentsthe CAS/SAFEA International Partnership Program for Creative Research TeamsShanghai Pasteur foundation
文摘Although IL-12 plays a critical role in priming Th1 and cytotoxic T lymphocyte(CTL) responses, Toll-like receptor(TLR) signaling only induces low amounts of IL-12 in dendritic cells and macrophages, implying the existence of stringent regulatory mechanisms. In this study, we sought to uncover the mechanisms underlying TLR-induced IL-12 expression and the Th1 response. By systemic screening, we identified a number of protein kinases involved in the regulation of TLRinduced IL-12 expression. In particular, PI3 K, ERK, and m TOR play critical roles in the TLR-induced Th1 response by regulating IL-12 and IL-10 production in innate immune cells. Moreover, we identified c-fos as a key molecule that mediates m TOR-regulated IL-12 and IL-10 expression in TLR signaling. Mechanistically, m TOR plays a crucial role in c-fos expression, thereby modulating NFκB binding to promoters of IL-12 and IL-10. By controlling the expression of a special innate gene program, m TOR can specifically regulate the TLR-induced T cell response in vivo. Furthermore, blockade of m TOR by rapamycin efficiently boosted TLR-induced antigen-specific T and B cell responses to HBV and HCV vaccines. Taken together, these results reveal a novel mechanism through which m TOR regulates TLR-induced IL-12 and IL-10 production, contributing new insights for strategies to improve vaccine efficacy.
基金supported by the National Natural Science Foundation of China (Nos. 51871204 and U1706221)。
文摘980 high-strength steel has been widely used in marine engineering structures due to its high strength and toughness.However,it is easily affected by the harsh environmental conditions(such as the presence of sulfate-reducing bacteria,SRB),leading to the risk of stress corrosion cracking(SCC).In this paper,the effects of SRB and its metabolites on hydrogen permeation and SCC mechanism of 980 steel in seawater solution were investigated by slow strain rate tensile test,scanning electron microscope,Xray energy spectroscopy,Raman spectroscopy and Devanathan-Stachurski double electrolytic cell.Results demonstrated that the SCC susceptibility of 980 steel was promoted in the presence of SRB,which was related to the cultivation time of the bacteria.When SRB were cultivated for 3 d and 6 d,the SCC mechanism was controlled by hydrogen-induced cracking(HIC);while the cultivation time extended to 11 d,the SCC of 980 steel was under the combined effect of the anodic dissolution(AD) and HIC mechanism.When cultivated for 16 d,the SCC of 980 steel was caused by the dominant AD.Both the SRB accelerated hydrogen permeation under cathodic depolarization process and SRB assisted AD(pitting corrosion)played an enhancing role in promoting SCC susceptibility of 980 steel.
基金Supported by INBRE P20RR016474USDA-NRI 200835203-19084USDA-AFRI 2009-65203-05716
文摘AIM:To investigate the effect of side-stream smoking on gut microflora composition,intestinal inflammation and expression of tight junction proteins.METHODS:C57BL/6 mice were exposed to side-stream cigarette smoking for one hour daily over eight weeks.Cecal contents were collected for microbial composition analysis.Large intestine was collected for immunoblotting and quantitative reverse transcriptase polymerase chain reaction analyses of the inflammatory pathway and tight junction proteins.RESULTS:Side-stream smoking induced significant changes in the gut microbiota with increased mouse intestinal bacteria,Clostridium but decreased Fermicutes(Lactoccoci and Ruminococcus),Enterobacteriaceae family and Segmented filamentous baceteria compared to the control mice.Meanwhile,side-stream smoking inhibited the nuclear factor-κB pathway with reduced phosphorylation of p65 and IκBα,accompanied with unchanged mRNA expression of tumor necrosis factor-α or interleukin-6.The contents of tight junction proteins,claudin3 and ZO2 were up-regulated in the large intestine of mice exposed side-stream smoking.In addition,side-stream smoking increased c-Jun N-terminal kinase and p38 MAPK kinase signaling,while inhibiting AMPactivated protein kinase in the large intestine.CONCLUSION:Side-stream smoking altered gut microflora composition and reduced the inflammatory response,which was associated with increased expression of tight junction proteins.
基金supported by the National Key Research and Development Program of China(2022YFD1300905)the National Natural Science Foundation of China(31960672)+3 种基金the Key Research and Development Program of Ningxia Hui Autonomous Region,China(2021BEF02020)the Top Discipline Construction Project of Pratacultural Science(NXYLXK2017A01)the Science and Technology Development Project of Jilin Province,China(20200201140JC)the Technology Cooperation High-Tech Industrialization Project of Jilin Province,China and the Chinese Academy of Sciences,(2022SYHZ0020).
文摘Lycium barbarum residue(LBR),a by-product of L.barbarum processing,is packed with bioactive components and can be potentially utilized as a feed additive in animal husbandry.However,the fundamental understanding of its effectiveness on livestock animals is still lacking,particularly in ruminants.To explore the effects of LBR on the growth performance,rumen fermentation parameters,ruminal microbes and metabolites of Tan sheep,sixteen fattening rams(aged 4 mon)were fed a basal diet(CON,n=8)or a basal diet supplemented with 5%LBR(LBR,n=8).The experiment lasted for 70 d,with 10 d adaptation period and 60 d treatment period.The results showed that the LBR enhanced the average daily feed intake,average daily gain(P<0.05),and ruminal total volatile fatty acids(P<0.01)while decreasing ammonia-nitrogen concentration and rumen pH value(P<0.05).Additionally,the LBR improved the relative abundances of Prevotella,Succiniclasticum,Ruminococcus,Coprococcus,Selenomonas,and Butyrivibrio(P<0.05)and reduced the relative abundances of Oscillospira and Succinivibrio(P<0.05).The LBR altered the ruminal metabolome(P<0.01)by increasing the abundances of ruminal metabolites involved in amino acids(e.g.,L-proline,L-phenylalanine,L-lysine,and L-tyrosine),pyrimidine metabolism(e.g.,uridine,uracil,and thymidine),and microbial protein synthesis(e.g.,xanthine and hypoxanthine).In conclusion,LBR had positive effects on the growth rate of Tan sheep as well as on rumen fermentation parameters,rumen microbiome and rumen metabolome.
基金Supported by Guangxi Experiment Animal Resource Sharing Platform Construction Project(15-235-07)
文摘[Objectives] The research aimed to explore the prevention and control effects of icaritin( ICT) on fruit fly model of Alzheimer's disease( AD),and provide theoretical basis for the development and application of new clinical medicine. [Methods]AD fruit fly model was established,and ICT was used to respectively intervene normal fruit fly and the fly transforming Aβ42. The test was divided into four groups:normal control group( Norm. group,feeding normal food solvent control),ICT intervention group of normal fruit fly( Norm. + ICT group,0. 04 mg/m L of ICT intervention),model control group( Aβ42 group,feeding normal feed solvent control) and model feeding ICT group( Aβ42 + ICT group,0. 04 mg/m L of ICT intervention). HE dyeing of fruit fly brain tissue,climbing ability,lifetime were respectively detected at whole level,and ATP,SOD and MDA contents of brain tissue were measured. [Results]Compared with AD fruit fly,there was no obvious hollow in fruit fly brain tissue slice of normal control group with the same age. Climbing ability,average lifetime,ATP,SOD and MDA contents in AD fruit fly group feeding ICT in old age were significantly improved. Normal control group was compared with normal control feeding ICT group,climbing ability,ATP,SOD and MDA contents had no statistical difference,and average lifetime was improved in normal feeding ICT group. [Conclusions]ICT could improve the behavior and lifetime of AD fruit fly,increase ATP content of brain tissue,enhance the ability to scavenge free radicals and resist lipid peroxidation,and protect AD fruit fly.
文摘The rising global incidence of diabetes mellitus(DM)and hyperuricemia presents a growing challenge to public health systems worldwide.Urate transporter-1(URAT1),a key renal urate transporter,has emerged as a promising therapeutic target for managing DM and its associated complications.Growing evidence suggests that URAT1’s role in metabolic disorders extends beyond its function in the kidney.Specifically,URAT1 can influence uric acid metabolism in multiple tissues including neural,hepatic,vascular smooth muscle,cardiac,and adipose tissue,thereby contributing to insulin resistance,inflammation,and end-organ damage.In this review,we comprehensively examine the extra-renal functions of URAT1,focusing on its roles in the hematopoietic system,heart,liver,adipose tissue,and vascular endothelium in the context of DM.This analysis highlights the multi-organ mechanisms through which URAT1 exerts its effects,offering valuable insights into its potential as a therapeutic target for this complex sys-temic metabolic disorder.
基金supported by the National Science Foundation of China(No.41576076)the National Environmental Corrosion Platform(NECP)the National Key Basic Research Program(‘‘973 Program,’’No.2014CB643300)
文摘Experiments were designed to simulate the corrosion of a low-carbon steel exposed to a marine splash zone. The composition and morphology of the rust were investigated using Raman spectroscopy, X-ray photoelectron spectroscopy, energy-dispersive spectrometry and scanning electron microscopy. Corrosion resistance of the rust films was demonstrated by the electrochemical impedance spectroscopy. The wettability of the steel surface was calculated from the data conceruing the wetting degree and the conductivity. The results showed that, in the initial stage, the products of the outer rust layer were mainly made up of Fe（Ⅲ） oxyhydroxide, while the main component of the inner rust layer was magnetite. With an increase in the corrosion time, the inner rust layer continuously turned into the outer rust layer. In addition, both rust layers became dense, thus playing a protective role with respect to matrix. The existence of the rust layer significantly prolonged the residence time of the seawater on the sample surface, a result that tends to improve the cathodic protection effect for steel structures exposed to marine splash zones.
基金financially supported by the National Science and Technology Major Project of China(No. 2011ZX05027-004-06)
文摘The influence of temperature on calcareous deposits formed under galvanostatic polarization mode was studied. The deposition was monitored by electrochemical impedance spectrum, and a supplementary loop in Nyquist diagram at high frequency was found to be an indicator of deposits precipitation with sufficient protection at above 20 ~C. An exponential increase of protectiveness with temperature was observed, which was quantified by linear polarization resistance technique. Observation by scanning electron microscope and X-ray diffraction analyses demonstrated that the critical temperature of calcium carbonate crystal form transition ranged from 15 to 20 ℃. Calcite formed below 15 ℃, while aragonite precipitated at above 20 ℃.
基金supported by the National Natural Science Foundation of China (Grants 51709191, 51606130, and 51506099)
文摘A visualized investigation was carried out on the effect of the diverging angle on the bubble motion and interfacial behavior in a Venturi-type bubble generator.It was found two or three large vortexes formed in the diverging section,resulting in strong reentrant jet flow in the front of the bubbles or slugs rushing out of the throat.The jet flow in return bumps into the ongoing bubbles or slugs,leading to strong interaction between the gas and liquid phases.The diverging angle has significant influence on the reentrant flow process and the performance of the bubble generator as well.Increasing the diverging angle results in the reentrant flow moving further forward to the upstream and intensifies the interaction between the two phases.As a consequence,the breakup or collapse of bubbles becomes more violent,whereby finer bubbles are generated.As such,the reentrant flow strongly links to the performance of the Venturi channel taken as a bubble generator,and that a moderate increase in the diverging angle can improve its performance without additional increase in flow resistance like that by increasing liquid flow rate.
文摘The risk of developing hepatocellular carcinoma(HCC) is strongly associated with hepatitis B virus infection.Hepatic angiomyolipoma(AML),a rare benign tumor,is composed of a heterogeneous mixture of adipose cells,smooth muscle cells and blood vessels.Here,we report the case of a 44-year-old man who developed HCC with a concomitant hepatic AML and a cavernous hemangioma,in the absence of cirrhosis.To our knowledge,based on an extensive literature search using the www.pubmed.gov website,this is the first report of an HCC case with both concomitant AML and cavernous hemangioma at the same position in the liver.The presence of the hepatitis B surface antigen was detected,but the liver function was normal.Clinical and pathological data were collected before and during the treatment.Hepatic AML was diagnosed based on the typical histological characteristics and immunohistochemical staining,which revealed,a positive staining with a melanocytic cell-specific monoclonal antibody.There was no evidence of tuberous sclerosis complex in this patient.Although the HCC was poor- to moderately-differentiated,the characteristics of the AML and the cavernous hemangioma in this patient did not match any criteria for malignancy.Hepatectomy followed by transarterial chemoembolization treatment were effective therapeutic methods for the adjacent lesions in this patient.This case is an interesting coincidence.
