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Determination of Carbon and Nitrogen Isotope Fractions in Asparagine, Aspartic Acid, Threonine and Methionine
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作者 Lamzira Pharulava Levani Eliashvili +1 位作者 Vakhtang Betlemidze Bachana Sulava 《American Journal of Analytical Chemistry》 CAS 2024年第1期30-42,共13页
The nomenclature for compounds that are modified with isotopes is growing every day. Compounds can be modified with isotopes either individually, in a functional group or groups, or completely with all atomic centers ... The nomenclature for compounds that are modified with isotopes is growing every day. Compounds can be modified with isotopes either individually, in a functional group or groups, or completely with all atomic centers of the element. This diversity of isotope-modified compounds increases the range of researches that can be studied using them. Compounds modified with isotopes of carbon-13 or nitrogen-15 can be converted into carbon monoxide, carbon dioxide and molecular nitrogen. Currently, only the average value of carbon-13 or nitrogen-15 isotopes can be determined. However, by directly determining the atomic share of these isotopes in organic compounds modified with isotopes, information about the isotopic centers of the element can be obtained. The atomic fraction of an element is defined as a single carbon or nitrogen isotope-modified center or centers, or all centers that are isotope-modified with that element at the same time. Carbon-13 or nitrogen-15 isotopes’ atomic fraction can be determined molecularly or with fragment ions of different elemental content, or both. This makes the method self-verifying, increasing the accuracy and reliability of the results obtained. Amino acids, such as asparagine, aspartic acid, methionine, and threonine, are essential for the human body. This proposed method of isotopic analysis will increase the possibilities for scientific research using these compounds. 展开更多
关键词 ASPARAGINE Aspartic Acid THREONINE methionine Mass Spectrometer Isotopic Analysis Atomic Share
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Feeding Practices and Use of Lysine and Methionine in Pigrationing on Intensified Pig Breeding in the West Center and Hauts Bassins Regions of Burkina Faso
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作者 Isidor Zangbéwindin Ouedraogo Timbilfou Kiendrebeogo +1 位作者 Aboubacar Toguyeni Chantal Yvette Kabore-Zoungrana 《Open Journal of Animal Sciences》 2024年第1期23-38,共16页
The aim of the study was to assess feeding practices and the use of lysine and methionine in pig rationing on intensified and semi-intensive pig breeding in the Koudougou and Bobo-Dioulasso areas. To this end, a cross... The aim of the study was to assess feeding practices and the use of lysine and methionine in pig rationing on intensified and semi-intensive pig breeding in the Koudougou and Bobo-Dioulasso areas. To this end, a cross-sectional survey was carried out on 87 breeding in these towns. A Discriminant Factorial Analysis (DFA) confirming a k-means classification of the data collected was used to retain 71 breeding divided into three breeding classes: Class A (32.4% of breeding), Class B (14.08%) and Class C (53.52%). The results show that the majority of pig breeders were men between the ages of 36 and 59. Average herd sizes were 35 ± 28;79 ± 42 and 89 ± 21 pigs for Classes A, B and C respectively. The main breeds of pig found on the breeding were crossbred, Large white, local, Landrace and Duroc. Class A (26.1%), B (30%) and C (15.8%) breeders were familiar with both lysine and methionine. Class A breeders distributed feed staggered (65.2%) and in rations (34.8%). Lysine (13%) and methionine (8.7%) were purchased at 5250 FCFA/kg. Those in class B distributed feed staggered (50%) and in the form of rations (50%), in which they incorporated lysine (30%) and methionine (30%) purchased at a cost of 2500 FCFA/kg and 3000 FCFA/kg respectively. Rationing and staggered feeding were practiced by 23.7% and 76.3% of Class C breeders respectively. Only lysine purchased at 3400 FCFA/kg was incorporated into rations by 10.5% of breeders. The high cost of lysine and methionine was incriminated by Class A (100%), B (33.3%) and C (50%) breeders. In conclusion, intensive pig breeding, the practice of rationing and the incorporation of the amino acids lysine and methionine are of ascending importance from classes C, A to B. The high cost of feedstuffs, particularly lysine and methionine, compromises their use in rations, which could have a negative impact on expected breeding performance. The screening and use of feeds rich in and/or enriched with these amino acids, through the development or adaptation of technologies, could improve the efficiency of rations and the productivity of intensive pig breeding in Burkina Faso. 展开更多
关键词 Feeding Practices LYSINE methionine Intensive Pig Breeding Burkina Faso
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Mechanisms underlying the role of endoplasmic reticulum stress in the placental injury and fetal growth restriction in an ovine gestation model
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作者 Hao Zhang Xia Zha +5 位作者 Yi Zheng Xiaoyun Liu Mabrouk Elsabagh Hongrong Wang Honghua Jiang Mengzhi Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期201-217,共17页
Background Exposure to bisphenol A(BPA),an environmental pollutant known for its endocrine-disrupting properties,during gestation has been reported to increase the risk of fetal growth restriction(FGR)in an ovine mode... Background Exposure to bisphenol A(BPA),an environmental pollutant known for its endocrine-disrupting properties,during gestation has been reported to increase the risk of fetal growth restriction(FGR)in an ovine model of pregnancy.We hypothesized that the FGR results from the BPA-induced insufficiency and barrier dysfunction of the placenta,oxidative stress,inflammatory responses,autophagy and endoplasmic reticulum stress(ERS).However,precise mechanisms underlying the BPA-induced placental dysfunction,and subsequently,FGR,as well as the potential involvement of placental ERS in these complications,remain to be investigated.Methods In vivo experiment,16 twin-pregnant(from d 40 to 130 of gestation)Hu ewes were randomly distributed into two groups(8 ewes each).One group served as a control and received corn oil once a day,whereas the other group received BPA(5 mg/kg/d as a subcutaneous injection).In vitro study,ovine trophoblast cells(OTCs)were exposed to 4 treatments,6 replicates each.The OTCs were treated with 400μmol/L BPA,400μmol/L BPA+0.5μg/m L tunicamycin(Tm;ERS activator),400μmol/L BPA+1μmol/L 4-phenyl butyric acid(4-PBA;ERS antagonist)and DMEM/F12 complete medium(control),for 24 h.Results In vivo experiments,pregnant Hu ewes receiving the BPA from 40 to 130 days of pregnancy experienced a decrease in placental efficiency,progesterone(P4)level and fetal weight,and an increase in placental estrogen(E2)level,together with barrier dysfunctions,OS,inflammatory responses,autophagy and ERS in type A cotyledons.In vitro experiment,the OTCs exposed to BPA for 24 h showed an increase in the E2 level and related protein and gene expressions of autophagy,ERS,pro-apoptosis and inflammatory response,and a decrease in the P4 level and the related protein and gene expressions of antioxidant,anti-apoptosis and barrier function.Moreover,treating the OTCs with Tm aggravated BPA-induced dysfunction of barrier and endocrine(the increased E2 level and decreased P4 level),OS,inflammatory responses,autophagy,and ERS.However,treating the OTCs with 4-PBA reversed the counteracted effects of Tm mentioned above.Conclusions In general,the results reveal that BPA exposure can cause ERS in the ovine placenta and OTCs,and ERS induction might aggravate BPA-induced dysfunction of the placental barrier and endocrine,OS,inflammatory responses,and autophagy.These data offer novel mechanistic insights into whether ERS is involved in BPA-mediated placental dysfunction and fetal development. 展开更多
关键词 AUTOPHAGY Bisphenol A Endoplasmic reticulum stress Fetal growth restriction Inflammatory responses SHEEP
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Associations of serum D-dimer and glycosylated hemoglobin levels with third-trimester fetal growth restriction in gestational diabetes mellitus
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作者 Ying Zhang Teng Li +1 位作者 Chao-Yan Yue Yun Liu 《World Journal of Diabetes》 SCIE 2024年第5期914-922,共9页
BACKGROUND Gestational diabetes mellitus(GDM)is a special type of diabetes that commonly occurs in women during pregnancy and involves impaired glucose tolerance and abnormal glucose metabolism;GDM is diagnosed for th... BACKGROUND Gestational diabetes mellitus(GDM)is a special type of diabetes that commonly occurs in women during pregnancy and involves impaired glucose tolerance and abnormal glucose metabolism;GDM is diagnosed for the first time during pregnancy and can affect fetal growth and development.AIM To investigate the associations of serum D-dimer(D-D)and glycosylated hemoglobin(HbA1c)levels with third-trimester fetal growth restriction(FGR)in GDM patients.METHODS The clinical data of 164 pregnant women who were diagnosed with GDM and delivered at the Obstetrics and Gynecology Hospital of Fudan University from January 2021 to January 2023 were analyzed retrospectively.Among these women,63 whose fetuses had FGR were included in the FGR group,and 101 women whose fetuses had normal body weights were included in the normal body weight group(normal group).Fasting venous blood samples were collected from the elbow at 28-30 wk gestation and 1-3 d before delivery to measure serum D-D and HbA1c levels for comparative analysis.The diagnostic value of serum D-D and HbA1c levels for FGR was evaluated by receiver operating characteristic analysis,and the influencing factors of third-trimester FGR in GDM patients were analyzed by logistic regression.RESULTS Serum fasting blood glucose,fasting insulin,D-D and HbA1c levels were significantly greater in the FGR group than in the normal group,while the homeostasis model assessment of insulin resistance values were lower(P<0.05).Regarding the diagnosis of FGR based on serum D-D and HbA1c levels,the areas under the curves(AUCs)were 0.826 and 0.848,the cutoff values were 3.04 mg/L and 5.80%,the sensitivities were 81.0%and 79.4%,and the specificities were 88.1%and 87.1%,respectively.The AUC of serum D-D plus HbA1c levels for diagnosing FGR was 0.928,and the sensitivity and specificity were 84.1%and 91.1%,respectively.High D-D and HbA1c levels were risk factors for third-trimester FGR in GDM patients(P<0.05).CONCLUSION D-D and HbA1c levels can indicate the occurrence of FGR in GDM patients in the third trimester of pregnancy to some extent,and their combination can be used as an important index for the early prediction of FGR. 展开更多
关键词 Gestational diabetes mellitus D-DIMER HEMOGLOBIN Fetal growth restriction Fasting blood glucose
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The effect of caloric restriction on genetical pathways
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作者 Mustafa Fevzi Karagöz A.Gülçin Sağdıçoğlu Celep 《Food Science and Human Wellness》 SCIE CSCD 2023年第5期1450-1457,共8页
Energy restriction is defined as reducing nutrient intake without dragging the organism into malnutrition. Energy restriction is preferred because it is a non-genetic intervention that increases life expectancy. Nicot... Energy restriction is defined as reducing nutrient intake without dragging the organism into malnutrition. Energy restriction is preferred because it is a non-genetic intervention that increases life expectancy. Nicotinamide adenine dinucleotide(NAD~+)and adenosine monophosphate(AMP)levels, which are the indicators of intracellular energy deficiency, increase with energy restriction. The increase in NAD~+ level stimulates sirtuin(SIRT)enzymes, and the increase in AMP level stimulates AMP-activated protein kinase(AMPK). Various mechanisms are regulated by stimulating these enzymes. By Forkhead box O(FoxO)transcription factors, the ability of resistance to oxidative stress increases, and antioxidant genes, DNA repair, and autophagy genes are stimulated. Apoptosis is induced by stimulation of the p53 protein, and tumor growth is suppressed by the disruption of aging cells. The suppression of phosphoinositide 3-kinase(PI3K)-/-Akt, and therefore mTOR signal stimulates autophagy and mitophagia, and cleanses damaged cells and organelles. Mitochondrial biogenesis is stimulated, antioxidant capacity increases, and inflammatory response decreases. Adipose tissue and lipid metabolism are regulated by the regulation of fatty acid synthesis and oxidation. As a consequence, the effects of caloric restriction on cellular metabolism are regulated through the genetic pathways. 展开更多
关键词 Caloric restriction Energy restriction SIRTUIN AMPK Mitochondrial biogenesis
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Effects of methionine treatment on storage quality and antioxidant activity of postharvest jujube fruit
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作者 LIU Yao LEI Xing-meng +2 位作者 GUO Yu-xiao YAO Shi-xiang ZENG Kai-fang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第9期2893-2904,共12页
Jujube fruits usually suffer from physiological disorders or infectious diseases during storage,leading to quality deterioration,softening,or rotting.Therefore,this study aims to investigate the effect of methionine s... Jujube fruits usually suffer from physiological disorders or infectious diseases during storage,leading to quality deterioration,softening,or rotting.Therefore,this study aims to investigate the effect of methionine soaking treatment on the postharvest jujube fruit decay rate and storage quality.Methionine treatment significantly reduced the decay rate of postharvest jujube fruit and effectively maintained fruit color and titratable acid.Methionine treatment effectively delayed the decrease of firmness,soluble solids,ascorbic acid,and lignin contents in jujube fruit.Methionine treatment reduced the content of alanine and phenylalanine,and increased the content of glycine in jujube fruit,but displayed no significant effect on total amino acid content.In addition,jujube fruits in the methionine treatment group had a higher total phenolic and flavonoid content and antioxidant capacity,both in free and bound forms.Compared with the control,methionine treatment also significantly increased the content of individual phenolic acid fractions(gallic acid,vanillic acid,and syringic acid)and flavonoid fractions(catechin,epicatechin,rutin)in free form as well as individual phenolic acid fractions in bound form(gallic acid and ferulic acid)in jujube fruits.Overall,this study suggested that the methionine treatment could be used as a prospective preservative to reduce the postharvest decay of jujube fruit and alleviate its nutritional quality deterioration during cold storage at 4°C. 展开更多
关键词 methionine JUJUBE decay rate sensory quality nutritional value
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Dietary Vitamin K Restriction and Effectiveness of Vitamin K Antagonists Prescribed at the CNHU-HKM University Cardiology Clinic/BENIN
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作者 Clémence Germaine Metonnou Charles Jérôme Sossa +4 位作者 Lamidhi Salami Rébécca Sabgohan Colette Azandjeme Camelle Mizehoun-Adossoda Virginie Mongbo 《Food and Nutrition Sciences》 2023年第10期928-940,共13页
Introduction: Their efficacy in preventing thrombotic and embolic events has been proven in numerous studies, but their narrow therapeutic index requires particular vigilance, especially in terms of biology. In additi... Introduction: Their efficacy in preventing thrombotic and embolic events has been proven in numerous studies, but their narrow therapeutic index requires particular vigilance, especially in terms of biology. In addition, treatment-related hemorrhagic complications are not uncommon. This study explores the influence of dietary vitamin K restriction on the efficacy of antivitamin K treatment at the University Cardiology Clinic of CNHU-HKM. Methods: Cross-sectional and descriptive study that took place from 25 April to 29 August 2019. Patients’ dietary behaviors and successive INR values were collected. Information on dietary intake was obtained by 2 non-consecutive 24-hour recalls. The effectiveness of VKA treatment was assessed by the “Time in Therapeutic Range” (TTR) of the INR. VKA treatment was considered effective for a TTR greater than 65%. Results: At the end of this study, 40 patients were surveyed. The mean age of the participants was 58.05 years ± 13.32 years, with a sex ratio of 1.35. Complete arrhythmia due to atrial fibrillation was the main indication for VKA treatment (37.50%) and fluindione was the most commonly prescribed drug (77.50%). The duration of treatment was less than or equal to 2 years in 47.5% of the subjects surveyed. Before starting treatment, 85% of patients received advice on restricting vitamin K-rich foods, and 45% of patients reported “food burnout” after a period of compliance with the restriction. The majority of respondents (97.50%) complied with the restriction on vitamin K-rich foods. All respondents had high energy intakes and a poor distribution of macronutrients, with a predominance of carbohydrates and proteins. 2.5% of respondents were on effective anti-vitamin K therapy with a TTR of over 65%. Conclusion: Restriction of vitamin K-rich foods is not conducive to effective treatment with vitamin K antagonists. 展开更多
关键词 Antivitamin K Dietary restriction Vitamin K Therapeutic Efficacy
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Lipid metabolism and m^(6)A RNA methylation are altered in lambs supplemented rumen-protected methionine and lysine in a low-protein diet
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作者 Kefyalew Gebeyew Chao Yang +7 位作者 Hui Mi Yan Cheng Tianxi Zhang Fan Hu Qiongxian Yan Zhixiong He Shaoxun Tang Zhiliang Tan 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期244-260,共17页
Background:Methionine or lysine has been reported to influence DNA methylation and fat metabolism,but their combined effects in N6-methyl-adenosine(m^(6)A)RNA methylation remain unclarified.The combined effects of rum... Background:Methionine or lysine has been reported to influence DNA methylation and fat metabolism,but their combined effects in N6-methyl-adenosine(m^(6)A)RNA methylation remain unclarified.The combined effects of rumen-protected methionine and lysine(RML)in a low-protein(LP)diet on lipid metabolism,m^(6)A RNA methylation,and fatty acid(FA)profiles in the liver and muscle of lambs were investigated.Sixty-three male lambs were divided into three treatment groups,three pens per group and seven lambs per pen.The lambs were fed a 14.5%crude protein(CP)diet(adequate protein[NP]),12.5%CP diet(LP),and a LP diet plus RML(LP+RML)for 60 d.Results:The results showed that the addition of RML in a LP diet tended to lower the concentrations of plasma leptin(P=0.07),triglyceride(P=0.05),and non-esterified FA(P=0.08).Feeding a LP diet increased the enzyme activity or m RNA expression of lipogenic enzymes and decreased lipolytic enzymes compared with the NP diet.This effect was reversed by supplementation of RML with a LP diet.The inclusion of RML in a LP diet affected the polyunsaturated fatty acids(PUFA),n-3 PUFA,and n-6 PUFA in the liver but not in the muscle,which might be linked with altered expression of FA desaturase-1(FADS1)and acetyl-Co A carboxylase(ACC).A LP diet supplemented with RML increased(P<0.05)total m^(6)A levels in the liver and muscle and were accompanied by decreased expression of fat mass and obesity-associated protein(FTO)and alk B homologue 5(ALKBH5).The m RNA expressions of methyltransferase-like 3(METTL3)and methyltransferase-like 14(METTL14)in the LP+RML diet group were lower than those in the other two groups.Supplementation of RML with a LP diet affected only liver YTH domain family(YTHDF2)proteins(P<0.05)and muscle YTHDF3(P=0.09),which can be explained by limited m^(6)Abinding proteins that were mediated in m RNA fate.Conclusions:Our findings showed that the inclusion of RML in a LP diet could alter fat deposition through modulations of lipogenesis and lipolysis in the liver and muscle.These changes in fat metabolism may be associated with the modification of m^(6)A RNA methylation. 展开更多
关键词 LAMBS Lipid metabolism Low-protein LYSINE methionine m^(6)A RNA methylation
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Calorie restriction potentiates epigallocatechin-3-gallate-mediated Nrf2 activation in hepatocytes of aged rats
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作者 Rajeswari Ravindran Malathi Manuel +2 位作者 Thangarajeswari Mohan Ravindran Jaganathan Kalaiselvi Periandavan 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2023年第10期421-430,共10页
Objective:To explore the combinatorial effect of epigallocatechin-3-gallate(EGCG)and calorie restriction on activation of nuclear factor erythroid 2-related factor 2(Nrf2),a transcription factor involved in the antiox... Objective:To explore the combinatorial effect of epigallocatechin-3-gallate(EGCG)and calorie restriction on activation of nuclear factor erythroid 2-related factor 2(Nrf2),a transcription factor involved in the antioxidant defense system of aged rats.Methods:Aged male Wistar rats were calorie-restricted and treated with EGCG orally for 45 days.The initial body weight of aged rats was recorded,and the final body weight was measured at the end of the experimental period.Serum lipid and lipoprotein status,oxidative stress markers such as free radicals and malondialdehyde levels,and reduced glutathione were assessed.In addition,RT-PCR and Western blotting analyses were performed.Results:Calorie restriction potentiated the effect of EGCG on enhancing antioxidant status,improving the levels of serum lipid and lipoproteins,upregulating Nrf2 and Bcl2,and downregulating Keap1,cullin3,Bax and cytochrome c in aged rats.Conclusions:Calorie restriction can promote EGCG-mediated Nrf2 activation in aged rats.This preliminary finding paves the way for a combinatory approach to replenishing the antioxidant status during aging,thereby reducing the risk for age-associated degenerative diseases. 展开更多
关键词 Aging Reactive oxygen species Calorie restriction EGCG NRF2 ANTIOXIDANT
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Effect of Sleep Hygiene Orientation on Social Cognition Impairments Due to Chronic Sleep Restriction in Mexican Medical Residents
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作者 Jiménez-Ceballos Betsabe Arana-Lechuga Debora Yoaly +2 位作者 Terán-Pérez Guadalupe Jovanna Escartín-Pérez Rodrigo Erick Velázquez-Moctezuma Javier 《Neuroscience & Medicine》 2023年第3期47-62,共16页
Introduction: Sleep is critical to human physiological function, cognitive performance, and emotional regulation. Healthcare personnel, especially physicians, are chronically exposed to long working hours, which are o... Introduction: Sleep is critical to human physiological function, cognitive performance, and emotional regulation. Healthcare personnel, especially physicians, are chronically exposed to long working hours, which are often accompanied by decreased sleep time. Clinical evidence indicates that these conditions affect their cognitive function and professional practice, but researchers in the field have not sufficiently explored the possible effects of reductions in sleep time on social cognition. Objective: The aim of this is to further explore the effects of sleep restriction among medical residents, the specific impairments in social cognition that it produces, and the effects of a sleep hygiene orientation on those impairments. Method: There were 124 medical residents (50 males, 74 females) who completed a daily sleep/work log, a battery of sleep tests/questionnaires, and neuropsychological evaluations. The participants then received a short course (8 hours) on basic concepts of sleep hygiene and sleep psychoeducation. Once the course was completed, participants filled out the questionnaires again. Results: The results indicate that sleep disturbances in medical residents were associated with severe neurocognitive and social cognition impairments. After the sleep hygiene intervention, neuropsychological function and sleep parameters improved, awareness increased, and social cognition performance significantly improved. Conclusion: Using sleep psychoeducation and sleep hygiene intervention in medical residents is a simple strategy to mitigate the effects of sleep restriction. 展开更多
关键词 Sleep Hygiene Shift Work Sleep restriction Cognitive Performance
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Caloric restriction-mimetics for the reduction of heart failure risk in aging heart: with consideration of gender-related differences
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作者 Lei Pang Xi Jiang +6 位作者 Xin Lian Jie Chen Er-Fei Song Lei-Gang Jin Zheng-Yuan Xia Hai-Chun Ma Yin Cai 《Military Medical Research》 SCIE CAS CSCD 2023年第1期113-133,共21页
The literature is full of claims regarding the consumption of polyphenol or polyamine-rich foods that offer some protection from developing cardiovascular disease(CVD). This is achieved by preventing cardiac hypertrop... The literature is full of claims regarding the consumption of polyphenol or polyamine-rich foods that offer some protection from developing cardiovascular disease(CVD). This is achieved by preventing cardiac hypertrophy and protecting blood vessels through improving the function of endothelium. However, do these interventions work in the aged human hearts? Cardiac aging is accompanied by an increase in left ventricular hypertrophy, along with diastolic and systolic dysfunction. It also confers significant cardiovascular risks for both sexes. The incidence and prevalence of CVD increase sharply at an earlier age in men than women. Furthermore, the patterns of heart failure differ between sexes, as do the lifetime risk factors. Do caloric restriction(CR)-mimetics, rich in polyphenol or polyamine, delay or reverse cardiac aging equally in both men and women? This review will discuss three areas:(1) mechanisms underlying age-related cardiac remodeling;(2) gender-related differences and potential mechanisms underlying diminished cardiac response in older men and women;(3) we select a few polyphenol or polyamine rich compounds as the CRmimetics, such as resveratrol, quercetin, curcumin, epigallocatechin gallate and spermidine, due to their capability to extend health-span and induce autophagy. We outline their abilities and issues on retarding aging in animal hearts and preventing CVD in humans. We discuss the confounding factors that should be considered for developing therapeutic strategies against cardiac aging in humans. 展开更多
关键词 Cardiovascular disease Cardiac aging Caloric restriction Gender difference Caloric restriction-mimetics Dietary compounds Clinical application
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Long-term implications of fetal growth restriction
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作者 Martina D'Agostin Chiara Di Sipio Morgia +1 位作者 Giovanni Vento Stefano Nobile 《World Journal of Clinical Cases》 SCIE 2023年第13期2855-2863,共9页
Fetal growth restriction(FGR),or intrauterine growth restriction(IUGR),is a complication of pregnancy where the fetus does not achieve its genetic growth potential.FGR is characterized by a pathological retardation of... Fetal growth restriction(FGR),or intrauterine growth restriction(IUGR),is a complication of pregnancy where the fetus does not achieve its genetic growth potential.FGR is characterized by a pathological retardation of intrauterine growth velocity in the curve of intrauterine growth.However,the FGR definition is still debated,and there is a lack of a uniform definition in the literature.True IUGR,compared to constitutional smallness,is a pathological condition in which the placenta fails to deliver an adequate supply of oxygen and nutrients to the developing fetus.Infants with IUGR,compared to appropriately grown gestational age infants,have a significantly higher risk of mortality and neonatal complications with long-term consequences.Several studies have demonstrated how suboptimal fetal growth leads to long-lasting physiological alterations for the developing fetus as well as for the newborn and adult in the future.The long-term effects of fetal growth retardation may be adaptations to poor oxygen and nutrient supply that are effective in the fetal period but deleterious in the long term through structural or functional alterations.Epidemiologic studies showed that FGR could be a contributing factor for adult chronic diseases including cardiovascular disease,metabolic syndrome,diabetes,respiratory diseases and impaired lung function,and chronic kidney disease.In this review we discussed pathophysiologic mechanisms of FGR-related complications and potential preventive measures for FGR. 展开更多
关键词 Fetal growth restriction Intrauterine chronic hypoxia Long-lasting physiological alterations Cardiovascular disease Metabolic syndrome Obstructive pulmonary disease
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Unenumerated Rights Clauses and the System of Restriction on Fundamental Rights——Another Construction Plan for Article 51 of the Constitution of PRC
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作者 杜强强 QIAN Chuijun 《The Journal of Human Rights》 2023年第1期91-108,共18页
According to constitutional jurisprudence in China,Article 51 of the Constitution is an unenumerated restrictive clause.Such theoretical construction fails to justify the differentiated restrictions established in the... According to constitutional jurisprudence in China,Article 51 of the Constitution is an unenumerated restrictive clause.Such theoretical construction fails to justify the differentiated restrictions established in the Constitution and makes it difficult to explain the constitutional status of human dignity. Article 51 implies the possibility of other theoretical constructions. It is not an unenumerated restriction clause but an unenumerated rights clause. It aims to provide guarantees for general freedom of action not enumerated in the Constitution rather than restricting fundamental rights. The actual benefit of this kind of theoretical construction lies in that it can establish the basis of the constitutional text for general freedom of action and promote the people’s correct understanding of the model of restriction on fundamental rights established by the Constitution of PRC. 展开更多
关键词 restriction on fundamental rights ¿legal construction ¿general freedom of action
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半胱氨酸、蛋氨酸对体外培养绒山羊次级毛囊生长及毛乳头细胞增殖的影响
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作者 康佳 段香茹 +6 位作者 尹雪姣 杨若晨 李太春 单新雨 陈美静 张英杰 刘月琴 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第2期515-527,共13页
旨在探讨半胱氨酸(Cys)、蛋氨酸(Met)对体外培养燕山绒山羊次级毛囊(SF)生长及毛乳头细胞(DPCs)增殖凋亡的影响。本研究选取1只1周岁左右健康雄性燕山绒山羊皮肤若干,完整分离的次级毛囊随机分成Cys试验组和Met试验组,每组各浓度3个重复... 旨在探讨半胱氨酸(Cys)、蛋氨酸(Met)对体外培养燕山绒山羊次级毛囊(SF)生长及毛乳头细胞(DPCs)增殖凋亡的影响。本研究选取1只1周岁左右健康雄性燕山绒山羊皮肤若干,完整分离的次级毛囊随机分成Cys试验组和Met试验组,每组各浓度3个重复,每个重复8根毛囊,Cys试验组添加浓度分别为0、40、80、120、160和200μg·mL^(-1);Met试验组添加浓度分别为0、10、15、20、25和30μg·mL^(-1)。毛囊培养7 d,每隔24 h观察毛囊生长形态并测量毛囊生长长度。从燕山绒山羊次级毛囊中提取、纯化DPCs,细胞计数并绘制DPCs生长曲线,将DPCs随机分为Cys试验组和Met试验组,每组各浓度6个重复,Cys试验组添加浓度分别为0、20、40、60、80、100μg·mL^(-1);Met试验组添加浓度分别为0、2、4、6、8、10μg·mL^(-1)。培养2 h后用CCK-8试剂盒进行细胞增殖活力测定,确定燕山绒山羊DPCs中Cys和Met的最适培养浓度,利用qRT-PCR技术检测不同浓度Cys和Met的DPCs增殖相关基因(PCNA、CCND1、CDC42、CDK 4)、凋亡相关基因(P21、P53、Bax、Caspase-3、Bcl-2)、皮肤细胞分化相关基因(IVL)及角蛋白相关基因(K10、K 14)mRNA表达水平。结果表明,与对照组相比,添加80和120μg·mL^(-1) Cys与10、15、20和25μg·mL^(-1) Met均可显著影响次级毛囊生长速率和累计生长长度(P<0.01),且120μg·mL^(-1) Cys和20μg·mL^(-1) Met促生长效果最好;添加20、40和60μg·mL^(-1) Cys可以显著影响DPCs增殖(P<0.05),添加40μg·mL^(-1) Cys显著上调PCNA、CCND1、CDK4、Bcl-2、K10、K 14和IVL基因mRNA表达量(P<0.05);添加6μg·mL^(-1) Met可以显著影响DPCs增殖(P<0.05),并显著上调PCNA、CCND1、CDK4、P21、Bcl-2、K 10和K 14基因mRNA表达量(P<0.05)。综上,添加Cys和Met可以显著促进长绒期燕山绒山羊次级毛囊生长,最适添加量分别为120μg·mL^(-1)和20μg·mL^(-1);添加Cys和Met可通过上调细胞增殖、分化、角蛋白等基因mRNA、下调细胞凋亡基因mRNA表达,促进乳头细胞增殖、抑制细胞凋亡进而促进燕山绒山羊次级毛囊生长。 展开更多
关键词 半胱氨酸 蛋氨酸 绒山羊 次级毛囊 毛乳头细胞 基因表达
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高含固污泥厌氧消化中甲硫氨酸分解抑制特性
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作者 韩芸 文天祥 +2 位作者 卓杨 周梦雨 余芬 《安全与环境学报》 CAS CSCD 北大核心 2024年第4期1587-1595,共9页
高含固污泥热水解厌氧消化条件下,沼气中硫化氢体积分数较常规含固率污泥厌氧消化低。沼气中硫化氢主要来源于污泥中含硫氨基酸的降解,而硫化氢体积分数下降与甲硫氨酸分解抑制相关。在测定高含固厌氧消化过程中含硫氨基酸分解中间产物... 高含固污泥热水解厌氧消化条件下,沼气中硫化氢体积分数较常规含固率污泥厌氧消化低。沼气中硫化氢主要来源于污泥中含硫氨基酸的降解,而硫化氢体积分数下降与甲硫氨酸分解抑制相关。在测定高含固厌氧消化过程中含硫氨基酸分解中间产物分布的基础上,以甲硫氨酸为基质对高含固厌氧消化污泥进行富集,分析富集后微生物种群结构特性及甲硫氨酸分解过程中挥发性有机硫分布,探讨高含固厌氧消化环境对甲硫氨酸分解过程的抑制特性。结果显示:高含固厌氧消化环境下,甲硫氨酸厌氧分解含硫产物包括甲硫醇、甲硫醚、二甲二硫和硫化氢。常规含固率及高含固率环境下,甲硫氨酸分解批次试验中硫化氢积累体积分数分别约为2417×10^(-6)和1418×10^(-6),表明高含固厌氧消化过程中硫化氢生成量下降可能由甲硫氨酸厌氧分解时中间产物积累导致。高含固污泥采用甲硫氨酸富集培养时,结果显示Pseudomonas相对丰度为26%,分解产物包括氨氮、甲硫醇和二甲二硫等。其中,二甲二硫先于甲硫醇达峰值,体积分数分别约为267.7×10^(-6)和164.9×10^(-6),推测反应前期甲硫醇快速转化为二甲二硫,后期速率减慢,甲硫醇开始累积。当氨氮质量浓度增至4000 mg/L时,二甲二硫生成速率降低16.79%,表明高含固系统的高氨氮环境可抑制甲硫氨酸分解产生二甲二硫。 展开更多
关键词 环境工程学 高含固污泥 厌氧消化 甲硫氨酸 二甲二硫 氨抑制
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我国限制使用的兽药在食品动物中的残留概况
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作者 叶妮 王亦琳 +3 位作者 陈超超 孙雷 明文庆 王雨霜 《中国兽药杂志》 2024年第1期29-36,共8页
从我国食品动物禁用、停用、特定时期不得使用以及允许使用但不得检出等层面,对我国兽药使用的限制、相关残留检测方法标准适用范围以及相关问题的分析和建议进行综述,以期为养殖业规范用药、食品安全监管部门政策制定和调整、科研机构... 从我国食品动物禁用、停用、特定时期不得使用以及允许使用但不得检出等层面,对我国兽药使用的限制、相关残留检测方法标准适用范围以及相关问题的分析和建议进行综述,以期为养殖业规范用药、食品安全监管部门政策制定和调整、科研机构针对不得检出兽药残留标准相关研究的开展提供参考。 展开更多
关键词 限制 兽药 食品动物 残留
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欧盟PFAS限制提案解读及其对制冷空调行业影响与应对
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作者 安青松 侯佳鑫 +1 位作者 史琳 戴晓业 《制冷学报》 CAS CSCD 北大核心 2024年第2期22-29,共8页
在《〈关于消耗臭氧层物质的蒙特利尔议定书〉基加利修正案》的履约和“双碳”目标的双重驱动下,制冷剂替代是制冷空调领域最为关注的热点之一。采用热物性相近的低GWP的HFOs制冷剂和天然制冷剂作为替代品,实现HFCs的削减被认为是较为... 在《〈关于消耗臭氧层物质的蒙特利尔议定书〉基加利修正案》的履约和“双碳”目标的双重驱动下,制冷剂替代是制冷空调领域最为关注的热点之一。采用热物性相近的低GWP的HFOs制冷剂和天然制冷剂作为替代品,实现HFCs的削减被认为是较为合适的替代技术路线;但随着2023年2月欧盟出台的PFAS限制提案,引发了对HFOs制冷剂替代前景的担忧,这可能影响全球制冷剂替代发展。因此,首先对PFAS物质进行了介绍,分析了含氟制冷剂与PFASs的关系,并对PFAS法案的形成脉络和关键内容进行了解读,总结了不同领域对此的观点,希望对未来制冷剂替代方案的制定提供一定思辨意义和参考价值。 展开更多
关键词 制冷剂替代 欧盟PFAS法案 PFASs HFOs 基加利修正案
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限制捐赠资产使用会使慈善组织获得更多的捐赠吗?
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作者 黄虹 李晓颖 +2 位作者 贺宇倩 刘江会 申强 《中国软科学》 CSCD 北大核心 2024年第4期102-111,共10页
捐赠者作为慈善资源的委托方,在推动慈善组织高质量发展过程中扮演了关键角色,然而目前文献对于其如何发挥治理行为还未有定论。利用中国慈善基金会2011—2020年的数据,研究慈善捐赠者主动治理行为对慈善组织未来捐赠收入的影响。研究发... 捐赠者作为慈善资源的委托方,在推动慈善组织高质量发展过程中扮演了关键角色,然而目前文献对于其如何发挥治理行为还未有定论。利用中国慈善基金会2011—2020年的数据,研究慈善捐赠者主动治理行为对慈善组织未来捐赠收入的影响。研究发现:捐赠者的主动治理行为能够增加慈善组织未来捐赠收入,但两者呈现倒U型关系,改善信息披露质量是其发挥主动治理效应的重要渠道。进一步的研究发现,上述治理效应与慈善组织的内、外部治理存在替代作用。在进一步划分捐赠收入类型以及慈善基金会规模后,本文发现捐赠者主动治理效应在大型基金会以及对机构捐赠收入的影响更为明显。研究结果体现了捐赠者主动治理的积极作用,为提升我国慈善组织筹款能力、促进公益慈善高质量发展、完善第三次分配体系提供了思路。 展开更多
关键词 慈善组织 主动治理 第三次分配 限定性净资产
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开放大学发展社区教育制约因素与对策研究
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作者 金炳顺 张金明 朱艳红 《辽宁高职学报》 2024年第2期92-94,99,共4页
针对地方开放大学发展社区教育面临思想认识不到位、办学体系不健全、运作模式滞后、办学经费匮乏和师资队伍不足等问题及制约因素,从提高政治站位、创新办学理念、实现社区教育和老年教育融合发展等方面提出发展社区教育的对策与建议,... 针对地方开放大学发展社区教育面临思想认识不到位、办学体系不健全、运作模式滞后、办学经费匮乏和师资队伍不足等问题及制约因素,从提高政治站位、创新办学理念、实现社区教育和老年教育融合发展等方面提出发展社区教育的对策与建议,为办好社区教育、推进学习型社会做出新贡献。 展开更多
关键词 开放大学 社区教育制约因素 对策
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宁夏香山群徐家圈组顶部薄层石灰岩锶同位素与局限海盆地分析
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作者 李向东 魏泽昳 +1 位作者 何幼斌 钟军伟 《地质学报》 EI CAS CSCD 北大核心 2024年第4期1229-1243,共15页
宁夏香山群主体为一套深水浊流沉积的灰绿色细砂岩夹泥岩,在鄂尔多斯盆地西缘及河西走廊地区下古生界占有重要的位置,其时代归属对于北祁连地区大地构造演化、宁夏区域地质和鄂尔多斯盆地西缘海相深水油气勘探均具有重要意义。本文采用... 宁夏香山群主体为一套深水浊流沉积的灰绿色细砂岩夹泥岩,在鄂尔多斯盆地西缘及河西走廊地区下古生界占有重要的位置,其时代归属对于北祁连地区大地构造演化、宁夏区域地质和鄂尔多斯盆地西缘海相深水油气勘探均具有重要意义。本文采用沉积学和沉积地球化学的方法,着重分析了香山群徐家圈组顶部薄层石灰岩锶同位素的特征,结果表明:①薄层石灰岩受成岩蚀变程度较小,^(87)Sr/^(86)Sr值基本可代表沉积时海水的特征;②^(87)Sr/^(86)Sr值在0.71057~0.71356之间,平均值为0.71189,远大于寒武纪和奥陶纪海水^(87)Sr/^(86)Sr值;③^(87)Sr/^(86)Sr值和盐度呈较好的负线性相关,和温度及Mn/Sr比值呈较好的正线性相关;④^(87)Sr/^(86)Sr值和Si含量略具负线性相关趋势,和Al含量及Mg含量具有较弱的负线性相关性。结合鄂尔多斯盆地西缘早古生代大地构造演化和香山群相关研究成果认为:徐家圈组顶部薄层石灰岩可能沉积于受古陆或水下隆起阻隔的局限海盆深水环境,沉积时海水主要受和硅铝质岩石进行充分锶同位素交换的海底热液及流经喀斯特风化壳的地表径流影响,与同期大洋海水相比具有高的^(87)Sr/^(86)Sr值. 展开更多
关键词 薄层石灰岩 锶同位素 局限海盆地 香山群 鄂尔多斯盆地西缘
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