Heat stress affects feed intake, milk production, and endocrine status in dairy cows. The temperaturehumidity index（THI） is employed as an index to evaluate the degree of heat stress in dairy cows. However, it is di...Heat stress affects feed intake, milk production, and endocrine status in dairy cows. The temperaturehumidity index（THI） is employed as an index to evaluate the degree of heat stress in dairy cows. However, it is difficult to ascertain whether THI is the most appropriate measurement of heat stress in dairy cows. This experiment was conducted to investigate the effects of heat stress on serum insulin, adipokines（leptin and adiponectin）, AMP-activated protein kinase（AMPK）, and heat shock signal molecules（heat shock transcription factor（HSF） and heat shock proteins（HSP）） in dairy cows and to research biomarkers to be used for better understanding the meaning of THI as a bioclimatic index. To achieve these objectives, two experiments were performed. The first experiment： eighteen lactating Holstein dairy cows were used. The treatments were： heat stress（HS, THI average=81.7, n=9） and cooling（CL, THI average=53.4, n=9）. Samples of HS were obtained on August 16, 2013, and samples of CL were collected on April 7, 2014 in natural conditions. The second experiment： HS treatment cows（n=9） from the first experiment were fed for 8 weeks from August 16, 2013 to October 12, 2013. Samples for moderate heat stress, mild heat stress, and no heat stress were obtained, respectively, according to the physical alterations of the THI. Results showed that heat stress significantly increased the serum adiponectin, AMPK, HSF, HSP27, HSP70, and HSP90（P〈0.05）. Adiponectin is strongly associated with AMPK. The increases of adiponectin and AMPK may be one of the mechanisms to maintain homeostasis in heat-stressed dairy cows. When heat stress treatment lasted 8 weeks, a higher expression of HSF and HSP70 was observed under moderate heat stress. Serum HSF and HSP70 are sensitive and accurate in heat stress and they could be potential indicators of animal response to heat stress. We recommend serum HSF and HSP70 as meaningful biomarkers to supplement the THI and evaluate moderate heat stress in dairy cows in the future.展开更多
OBJECTIVE: To examine the acute toxicity of an aqueous extract of Aspidopterys obcordata(A. obcordata) in Sprague Dawley rats.METHODS: The rats were orally administered a dose of 5000 mg/kg body weight and observed co...OBJECTIVE: To examine the acute toxicity of an aqueous extract of Aspidopterys obcordata(A. obcordata) in Sprague Dawley rats.METHODS: The rats were orally administered a dose of 5000 mg/kg body weight and observed continuously for 6 h and then daily for 14 days. Control rats were administered distilled water. The effect of the extract on general behavior, body weight, and food and water intake were measured.After 14 days, the rats were sacrificed and their organs(liver, heart, spleen, lungs, kidney, adrenal glands, ovaries, and testes) were removed for macroscopic examination. The body and organ weights in addition to hematology(e.g., hemoglobin and white blood cell counts) and clinical blood biochemistry(e.g., albumin and bilirubin) were also examined.RESULTS: There were no deaths recorded, and the rats treated with A. obcordata showed no signs of toxicity. All measured parameters in rats treated with A. obcordata were unaffected when compared with those in control rats. The acute toxicity(LD_(50))was estimated to be > 5000 mg/kg body weight.CONCLUSION: Our results demonstrate the safety of an acute oral administration of an aqueous extract of A. obcordata in rats and indicate that future subacute and long-term toxicity testing of A. obcordata is warranted.展开更多
OBJECTIVE:To investigate biological indicators of sub-optimal health status and provide means of objective assessment of sub-optimal health status.METHODS:We set the unified standards for diagnosing a SHS.We tested va...OBJECTIVE:To investigate biological indicators of sub-optimal health status and provide means of objective assessment of sub-optimal health status.METHODS:We set the unified standards for diagnosing a SHS.We tested various laboratory indicators in 407 cases that we selected randomly from2807 subjects and collected 15 mL of fasting venous blood from each case.We measured serum immunoglobulin A(IgA)and immunoglobulin G(IgG)concentrations,serum beta endorphins(β-EP),cortisol(C),testosterone(T),plasma adrenocorticotropic hormone(ACTH)and serum T lymphocyte subsets CD3+and CD4+.RESULTS:Mean serum testosterone concentrations and their ratio to cortisol(C)concentrations weresignificantly higher in the healthy group than in those with sub-optimal health status(P<0.01).Mean serum CD3+concentrations were significantly higher in those with sub-optimal health status than in the healthy group(P<0.05).CONCLUSION:Decreased serum testosterone/cortisol ratio may be an objective indication of sub-optimal health status.Changes in neuroendocrine and immunological indicators may explain some of the symptoms,including malaise and poor work performance,attributable to persistent or relapsing fatigue in subjects with sub-optimal health status.展开更多
基金Project supported by the National Basic Research Program(973)of China(No.2011CB100805)the Modern Agro-Industry Technology Research System of China(No.nycytx-04-01)the Agricultural Science and Technology Innovation Program(No.ASTIP-IAS12),China
文摘Heat stress affects feed intake, milk production, and endocrine status in dairy cows. The temperaturehumidity index（THI） is employed as an index to evaluate the degree of heat stress in dairy cows. However, it is difficult to ascertain whether THI is the most appropriate measurement of heat stress in dairy cows. This experiment was conducted to investigate the effects of heat stress on serum insulin, adipokines（leptin and adiponectin）, AMP-activated protein kinase（AMPK）, and heat shock signal molecules（heat shock transcription factor（HSF） and heat shock proteins（HSP）） in dairy cows and to research biomarkers to be used for better understanding the meaning of THI as a bioclimatic index. To achieve these objectives, two experiments were performed. The first experiment： eighteen lactating Holstein dairy cows were used. The treatments were： heat stress（HS, THI average=81.7, n=9） and cooling（CL, THI average=53.4, n=9）. Samples of HS were obtained on August 16, 2013, and samples of CL were collected on April 7, 2014 in natural conditions. The second experiment： HS treatment cows（n=9） from the first experiment were fed for 8 weeks from August 16, 2013 to October 12, 2013. Samples for moderate heat stress, mild heat stress, and no heat stress were obtained, respectively, according to the physical alterations of the THI. Results showed that heat stress significantly increased the serum adiponectin, AMPK, HSF, HSP27, HSP70, and HSP90（P〈0.05）. Adiponectin is strongly associated with AMPK. The increases of adiponectin and AMPK may be one of the mechanisms to maintain homeostasis in heat-stressed dairy cows. When heat stress treatment lasted 8 weeks, a higher expression of HSF and HSP70 was observed under moderate heat stress. Serum HSF and HSP70 are sensitive and accurate in heat stress and they could be potential indicators of animal response to heat stress. We recommend serum HSF and HSP70 as meaningful biomarkers to supplement the THI and evaluate moderate heat stress in dairy cows in the future.
基金National Natural Science Foundation of China(Transport Characters and Mechanism Research of Multiplicity Ingredient TCM Utilizing Sensitive Bioactivity in Caco-2 Cell Model,No.81173645)Program for Innovative Research Team in IMPLAD(Discovery and foundation of new drug of TCM)+2 种基金a grant from the Basic Scientific Research Special of the Central Public Welfare Research Institutes of IMPLAD(Research on the Kidney Stone Activities and Preliminary Mechanisms of Aspidopterys Obcordata,No.YZYN-15-06)PUMC Youth Fund(Study of Anti-Tumor Activities of Pegylation Artemisinin Prodrugs Based on PK-PD Binding Model,No.33320140076)Beijing Municipal Natural Science Foundation(Preparation of Silica-Based Nanoparticles/PDMS Hybrid Membranes for Pervaporation of Ethanol/Water Mixtures,No.2132010)
文摘OBJECTIVE: To examine the acute toxicity of an aqueous extract of Aspidopterys obcordata(A. obcordata) in Sprague Dawley rats.METHODS: The rats were orally administered a dose of 5000 mg/kg body weight and observed continuously for 6 h and then daily for 14 days. Control rats were administered distilled water. The effect of the extract on general behavior, body weight, and food and water intake were measured.After 14 days, the rats were sacrificed and their organs(liver, heart, spleen, lungs, kidney, adrenal glands, ovaries, and testes) were removed for macroscopic examination. The body and organ weights in addition to hematology(e.g., hemoglobin and white blood cell counts) and clinical blood biochemistry(e.g., albumin and bilirubin) were also examined.RESULTS: There were no deaths recorded, and the rats treated with A. obcordata showed no signs of toxicity. All measured parameters in rats treated with A. obcordata were unaffected when compared with those in control rats. The acute toxicity(LD_(50))was estimated to be > 5000 mg/kg body weight.CONCLUSION: Our results demonstrate the safety of an acute oral administration of an aqueous extract of A. obcordata in rats and indicate that future subacute and long-term toxicity testing of A. obcordata is warranted.
基金Supported by China National Funds for Distinguished Young Scientists(No.30825046)Hi-Tech Research and Development Program of China(863 Program),No.2008AA02Z406Program for Innovative Research Team in Beijing University of Chinese Medicine(No.2011CXTD-07)
文摘OBJECTIVE:To investigate biological indicators of sub-optimal health status and provide means of objective assessment of sub-optimal health status.METHODS:We set the unified standards for diagnosing a SHS.We tested various laboratory indicators in 407 cases that we selected randomly from2807 subjects and collected 15 mL of fasting venous blood from each case.We measured serum immunoglobulin A(IgA)and immunoglobulin G(IgG)concentrations,serum beta endorphins(β-EP),cortisol(C),testosterone(T),plasma adrenocorticotropic hormone(ACTH)and serum T lymphocyte subsets CD3+and CD4+.RESULTS:Mean serum testosterone concentrations and their ratio to cortisol(C)concentrations weresignificantly higher in the healthy group than in those with sub-optimal health status(P<0.01).Mean serum CD3+concentrations were significantly higher in those with sub-optimal health status than in the healthy group(P<0.05).CONCLUSION:Decreased serum testosterone/cortisol ratio may be an objective indication of sub-optimal health status.Changes in neuroendocrine and immunological indicators may explain some of the symptoms,including malaise and poor work performance,attributable to persistent or relapsing fatigue in subjects with sub-optimal health status.
