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Edaravone-loaded poly(amino acid) nanogel inhibits ferroptosis for neuroprotection in cerebral ischemia injury
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作者 Yunhan Zhang Zhulin Zou +5 位作者 Shuang Liu Fangfang Chen Minglu Li Haoyang Zou Haiyan Liu Jianxun Ding 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2024年第2期89-101,共13页
Neurological injury caused by ischemic stroke is a major cause of permanent disability and death. The currently available neuroprotective drugs fail to achieve desired therapeutic efficacy mainly due to short circulat... Neurological injury caused by ischemic stroke is a major cause of permanent disability and death. The currently available neuroprotective drugs fail to achieve desired therapeutic efficacy mainly due to short circulation half-life and poor blood−brain barrier (BBB) permeability. For that, an edaravone-loaded pH/glutathione (pH/GSH) dual-responsive poly(amino acid) nanogel (NG/EDA) was developed to improve the neuroprotection of EDA. The nanogel was triggered by acidic and EDA-induced high-level GSH microenvironments, which enabled the selective and sustained release of EDA at the site of ischemic injury. NG/EDA exhibited a uniform sub-spherical morphology with a mean hydrodynamic diameter of 112.3 ± 8.2 nm. NG/EDA efficiently accumulated at the cerebral ischemic injury site of permanent middle cerebral artery occlusion (pMCAO) mice, showing an efficient BBB crossing feature. Notably, NG/EDA with 50 µM EDA significantly increased neuron survival (29.3%) following oxygen and glucose deprivation by inhibiting ferroptosis. In addition, administering NG/EDA for 7 d significantly reduced infarct volume to 22.2% ± 7.2% and decreased neurobehavioral scores from 9.0 ± 0.6 to 2.0 ± 0.8. Such a pH/GSH dual-responsive nanoplatform might provide a unique and promising modality for neuroprotection in ischemic stroke and other central nervous system diseases. 展开更多
关键词 Poly(amino acid)nanogel Controlled drug delivery Inhibition of ferroptosis NEUROPROTECTION Cerebral ischenia injury therapy
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Effect of topiramate on partial excitatory amino acids in hippocampal dentate gyrus of rats after alcohol withdrawal
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作者 Qinghua Yang Guang Wu +2 位作者 Haiying Jiang Yuanzhe Jin Songbiao Cui 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第2期147-150,共4页
BACKGROUND: Many researches have indicated that the imbalances of various amino acid transmitters and neurotransmitters in brain are involved in the formation of alcohol withdrawal, especially that glutamic acid is o... BACKGROUND: Many researches have indicated that the imbalances of various amino acid transmitters and neurotransmitters in brain are involved in the formation of alcohol withdrawal, especially that glutamic acid is one of the important transmitters for alcohol tolerance in central nervous system. OBJECTIVE: To observe the changes of excitatory amino acids in hippocampal dentate gyrus in rats with long-term alcohol drinking after withdrawal under consciousness, and investigate the therapeutic effect of topiramate on alcohol withdrawal. DESIGN : A randomized control animal experiment SETTING : Department of Neurology, Affiliated Hospital of Yanbian University MATERIALS: Thirty male Wistar rats of 4 months old, weighing 300-350 g, were purchased from the Experimental Animal Department, Medical College of Yanbian University. Topiramate was produced by Swish Cilag Company, and the batch number was 02CS063. METHODS: The experiments were carried out in the Department of Physiology, Medical College of Yanbian University from August 2005 to February 2006. ① The rats were divided randomly into three groups: control group (n=10), alcohol group (n=10) and topiramate-treated group (n=10). Rats in the alcohol group and topiramate-treated group were given intragastric perfusion of 500 g/L alcohol (10 mL/kg), once a day for 4 weeks successively, and then those in the topiramate-treated group were treated with 80 mg/kg topiramate at 24 hours after the last perfusion of alcohol, once a day for 3 days successively. Rats in the control group were intragastricly given isovolume saline. ② The withdrawal symptoms were assessed at 6, 30, 48 and 72 hours after the last perfusion of alcohol by using the withdrawal rating scale set by Erden et al, which had four observational indexes of stereotyped behaviors, agitation, tail stiffness and abnormal posture, each index was scored by 5 points, the higher the score, the more obvious the symptoms. ③ The contents of aspartic acid and glutamic acid in hippocampal dentate gyrus were detected with microdialysis technique and high-performance liquid chromatograpy (HPLC) respectively at 6, 30, 48 and 72 hours after the last perfusion of alcohol in the three groups. MAIN OUTCOME MEASURES : ① Scoring results of alcohol withdrawal symptoms; ② Changes of the contents of aspartic acid and glutamic acid in hippocampal dentate gyrus at the alcohol withdrawal symptoms, and the effects of topiramate. RESULTS: Seven rats were excluded due to inaccurate localization and natural death, and 23 rats were involved in the analysis of results. ①In the alcohol group, the scores of alcohol withdrawal symptoms at 30 and 48 hours after the last perfusion of alcohol were obviously higher than those in the control group (10.50±0.96, 14.17±1.25; 3.50±0.92, 3.16±0,31; P 〈 0.01). In the topiramate-treated group, the scores at 30 hours after the last perfusion of alcohol (6.06±0.82, 3.50±0.92, P 〈 0.05), and the withdrawal scores at 48 and 72 hours were close to those in the control group (4.57±0.58, 3.30±0.71; 3.16±0.31, 3.66±0.67; P 〉 0.05).② Changes of the contents of glutamic acid in hippocampal dentate gyrus: In the alcohol group, the content of glutamic acid at 48 hours after the last perfusion of alcohol was significantly increased as compared with that at 6 hours [(143.32±11.42)%, (99.12±0.69)%; P 〈 0.05], and that at 72 hours was close to that at 6 hours [(78.50±16.40)%, (99.12±0.69)%; P 〉 0.05]. The contents of glutamic acid had no obvious differences at 6, 30, 48 and 72 hours after the last perfusion of alcohol in the topiramate-treated group [(100.30±0.37)%, (118.91±10.40)%, (99.55±12.81)%, (99.08±11.42)%; P 〉 0.05], The content of glutamic acid at 48 hours after the last perfusion of alcohol in the topiramate-treated group was obviously lower than that in the alcohol group (P 〈 0.05), and those at 30 and 72 hours were close (P 〉 0.05). ③ Changes of the contents of aspartic acid in hippocampal dentate gyrus: In the alcohol group, the contents of aspartic acid at 30 and 48 hours after the last perfusion of alcohol were significantly increased as compared with that at 6 hours [(126.60±8.67)%, (129.17±10.40)%, (99.25±0.87)%; P 〈 0.05], and that at 72 hours was close to that at 6 hours [(89.87±9.93)%, (99.25±0.87)%; P 〉 0.05]. The contents of aspartic acid had no obvious differences at 6, 30, 48 and 72 hours after the last perfusion of alcohol in the topiramate-treated group [(100.27±0.32)%, (120.81 ±12.63)%, (98.91±7.83)%, (85.92±8.07)%; P 〉 0.05]. The content of aspartic acid at 48 hours after the last perfusion of alcohol in the topiramate-treated group was obviously lower than that in the alcohol group (P 〈 0.05), and those at 30 and 72 hours were close (P 〉 0.05). CONCLUSION: ① The occurrences of alcohol withdrawal symptoms are correlated with the increased contents of excitatory amino acids in hippocampal dentate gyrus in rats. ② Topiramate can alleviate the alcohol withdrawal symptoms, which may be correlated with the decreased contents of excitatory amino acids in hippocampal dentate gyrus in rats. 展开更多
关键词 effect of topiramate on partial excitatory amino acids in hippocampal dentate gyrus of rats after alcohol withdrawal
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Hepatoprotective properties of oleanolic and ursolic acids in anti-tubercular drug-induced liver damage 被引量:10
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作者 Gabriel A.Gutiérrez-Rebolledo Georgina A.Siordia-Reyes +1 位作者 Mariana Meckes-Fischer Adelina Jiménez-Arellanes 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第7期625-632,共8页
Objective:To estimate to what extent the mixture of ursolic acid and oleanolic acid,in addition to the antitubercular standard regime,affects the hepatotoxicity profile.Methods:Liver injury was induced in male BALB/c ... Objective:To estimate to what extent the mixture of ursolic acid and oleanolic acid,in addition to the antitubercular standard regime,affects the hepatotoxicity profile.Methods:Liver injury was induced in male BALB/c mice by administering,per os and daily for 11 weeks,a combination of anti-Tubercular(anti-TB) agents Rifampicin(10 mg/kg),Isoniazid(10 mg/kg),and Pyrazinamide(30 mg/kg).The ursolic acid and oleanolic acid mixture at doses of 100 or 200 μg/mouse/day was subcutaneously injected throughout the entire study period(11 weeks).Biochemical and hematological analysis was supplemented by liver histological examination.Results:Animals treated with the mixture of triterpenic acids exhibited significantly decreased aspartate transaminase and alanine aminotransferase levels and amelioration of the histopathological alterations produced by the anti-TB drugs.Conclusions:The triterpene mixture is able to prevent the steatosis induced by the anti-TB drugs. 展开更多
关键词 Ursolic acid Oleanolic acid Hepatoprotector effect ANTITUBERCULAR drugS TRITERPENES
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Effect of borneol, moschus, storax, and acorus tatarinowii on expression levels of four amino acid neurotransmitters in the rat corpus striatum 被引量:6
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作者 Na Zhang Ping Liu Xinrong He 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第6期440-444,共5页
The present study collected cerebrospinal fluid samples from the corpus striatum in rats treated with borneol, moschus, storax, and acorus tatarinowii using brain microdialysis technology. Levels of excitatory neurotr... The present study collected cerebrospinal fluid samples from the corpus striatum in rats treated with borneol, moschus, storax, and acorus tatarinowii using brain microdialysis technology. Levels of excitatory neurotransmitters aspartic acid and glutamate, as well as inhibitory neurotransmitters glycine and ^-aminobutyric acid, were measured in samples using reversed-phase high-performance liquid chromatography, phosphate gradient elution, and fluorescence detection. Results showed that concentrations of all four amino acid neurotransmitters significantly increased in the corpus striatum following treatment with borneol or moschus, but effects due to borneol were more significant than moschus. Acorus tatarinowii treatment increased ^-aminobutyric acid expression, but decreased glutamate concentrations. Storax increased aspartic acid concentrations and decreased glycine expression. Results demonstrated that borneol and moschus exhibited significant effects on con amino acid neurotransmitter expression; storax exhibited excitatory effects and acorus tatarinowii resulted in inhibitory effects. 展开更多
关键词 acorus tatarinowii amino acid BORNEOL MICRODIALYSIS high-performance liquid chromatography MOSCHUS NEUROTRANSMITTER resuscitation drugs storax
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Amino acid transporters: Emerging roles in drug delivery for tumor-targeting therapy 被引量:3
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作者 Ling Zhang Chengguang Sui +1 位作者 Wenhan Yang Qiuhua Luo 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2020年第2期192-206,共15页
Amino acid transporters,which play a vital role in transporting amino acids for the biosynthesis of mammalian cells,are highly expressed in types of tumors.Increasing studies have shown the feasibility of amino acid t... Amino acid transporters,which play a vital role in transporting amino acids for the biosynthesis of mammalian cells,are highly expressed in types of tumors.Increasing studies have shown the feasibility of amino acid transporters as a component of tumortargeting therapy.In this review,we focus on tumor-related amino acid transporters and their potential use in tumor-targeting therapy.Firstly,the expression characteristics of amino acid transporters in cancer and their relationship with tumor growth are reviewed.Secondly,the recognition requirements are discussed,focusing on the“acidbase”properties,conformational isomerism and structural analogues.Finally,recent developments in amino acid transporter-targeting drug delivery strategies are highlighted,including prodrugs and nanocarriers,with special attention to the latest findings of molecular mechanisms and targeting efficiency of transporter-mediated endocytosis.We aim to offer related clues that might lead to valuable tumor-targeting strategies by the utilization of amino acid transporters. 展开更多
关键词 amino acid TRANSPORTER TUMOR-TARGETING drug delivery PROdrug NANOCARRIERS
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Study of Complexes of Lanthanum with Amino Acids by Titration Calorimeter 被引量:2
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作者 Ye Gang, Wang Cun-xin, Qu Song-sheng College of Chemistry and Environment Science, Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2000年第4期479-484,共6页
The stability constants and thermodynamic functions for complexes of lanthanum with eight kind of amino acids according to 1∶1 and 1∶2 in proportion have been determined by titration calorimeter at 298.15 K. The ent... The stability constants and thermodynamic functions for complexes of lanthanum with eight kind of amino acids according to 1∶1 and 1∶2 in proportion have been determined by titration calorimeter at 298.15 K. The enthalpy change makes a predominant contribution to the stability of these complexes. The ring in amino acid associated with lanthanum ion helps to enhance the stability of complexes. Steric effects between rings in complexes leads to that the equilibrium constants of reaction of the complexes (1∶2) is much less than that of the complexes (1∶1). 展开更多
关键词 titration calorimeter rare earth amino acid COMPLEXES steric effects
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Study on gamma-ray attenuation characteristics of some amino acids for 133Ba,137Cs, and 60Co sources 被引量:1
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作者 Reza Bagheri Ali Yousefi Seyed Pezhman Shirmardi 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第2期67-81,共15页
Amino acids are the building blocks of proteins,which are the most abundant macromolecules in living cells.From the standpoint of the photon interaction cross sections of amino acids,the mass attenuation coefficients,... Amino acids are the building blocks of proteins,which are the most abundant macromolecules in living cells.From the standpoint of the photon interaction cross sections of amino acids,the mass attenuation coefficients,half and tenth value layers,mean free path,effective atomic and electronic cross sections,effective atomic number,and effective electron density of fifteen essential amino acids have been determined for 133Ba,137Cs,and 60Co gamma-ray sources.The MCNP-4C code and the XCOM program have been used to calculate these parameters.The results have been compared to the available experimental and theoretical data.The theoretical results agreed with the experimental data,with RD values of ≤±7%.In the energy region of 81-1332.5 keV,it was found that the μm,σa,and revalues of the amino acids decreased as the photon energy increased,and the increasing density of amino acids had no steady effect on these quantities.Additionally,results demonstrated that the HVL,TVL,and MFP values increased with the increase in photon energy.The μm,σa,and Zeff values of aspartic acid were the highest among those of all amino acids,and they were the lowest for isoleucine.The Zeff value of each sample containing H,C,N,and O atoms was nearly constant in the studied energy region.The Neffvalues of the studied amino acids varied in the range of 3.14×10^23-3.44×10^23 electron/g.Furthermore,the Neffvalues were approximately independent of the amino acid type in this energy region. 展开更多
关键词 amino acids Mass attenuation coefficient effective electron density and atomic number MCNP-4C XCOM
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Preparation and Spectroscopic of Vanadyl(Ⅱ) Vitamin D3 Amino Acid Mixed Complexes as Insulin Mimetic Drug
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作者 Enas Aljuhani Amnah M.A.Alsuhaibani +3 位作者 A.M.El-Di damony N.Hassan Sameh Abo Taleb Moamen S.Refat 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2019年第7期2316-2324,共9页
A new six intraperitoneal injection insulin-mimetic vanadyl(Ⅱ) compounds [(VD3^-1)(VO^+2)(AAn^-1)](where(n=1~6);AA1=isoleucine, AA2=threonine, AA3=proline, AA4=phenylalanine, AA5=lysine and AA6=glutamine) were synthe... A new six intraperitoneal injection insulin-mimetic vanadyl(Ⅱ) compounds [(VD3^-1)(VO^+2)(AAn^-1)](where(n=1~6);AA1=isoleucine, AA2=threonine, AA3=proline, AA4=phenylalanine, AA5=lysine and AA6=glutamine) were synthesized by the chemical reactions between vitamin D3(VD3), VOSO4 and amino acids(AAn) with equal molar ratio 1∶1∶1 in neutralized media. The structures of these complexes were elucidated by spectroscopic methods like, infrared and solid reflectance spectroscopes. Magnetic moments and electronic spectra reveal square pyramid geometrical structure of the complexes. The infrared spectra assignments of these complexes revealed that the chelation towards vanadyl(Ⅳ) ions existed via deprotonation of the hydroxyl group of VD3 drug ligand and so amino acids act as bidentate ligand via N-amino and O-carboxylate groups. The anti-diabetic efficiency of these complexes were evaluated against streptozotocin induced diabetic male albino rats. 展开更多
关键词 INSULIN alternative Diabetes drug VO^2+ ion VITAMIN D3 amino acid SPECTROSCOPIC
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Amino Acid Sensing Using an Ion-Sensitive Field-Effect Transistor 被引量:2
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作者 Akimitsu Kugimiya Kaori Kohara 《Journal of Chemistry and Chemical Engineering》 2012年第5期397-400,共4页
关键词 离子敏场效应晶体管 氨基酸 氨酰-TRNA合成酶 遥感应用 生物传感器 选择性反应 ISFET 酪氨酸
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Combined Action of Copper with IAA on Individual Amino Acids and Microelement in Pods of Two Broad Bean Cultivars
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作者 Hamdia Mahmoud Abd El-Samad Mohamed Abdo Kheder Shaddad Khloud Nagy Shaker 《American Journal of Plant Sciences》 2019年第4期670-697,共28页
It is worthy to mention that the two broad bean cultivars displayed a surprising situation during the fruiting stage of growth. The absolute amount of pods yield was higher in cv. Assiut 125 than in cv. Assiut 84. Thi... It is worthy to mention that the two broad bean cultivars displayed a surprising situation during the fruiting stage of growth. The absolute amount of pods yield was higher in cv. Assiut 125 than in cv. Assiut 84. This situation was in contrast with that in the vegetative stage, where cv. Assiut 84 produced greater vegetative growth than cv. Assiut 125. Although the cv. Assiut 84 was less affected by the highest dose of copper, the cv. Assiut 125 was greatly affected by this dose. However, another surprising situation was recorded when the absolute values of fresh and dry matter of cv. Assiut 125 were much higher than cv. Assiut 84 at any used copper concentration. The fresh matters of the pods of cv. Assiut 84 and cv. Assiut 125 were 7.24 and 10.16 gm at the level of control and 6.69 and 7.59 gm at the level of 350 ppm Cu, respectively. Their dry matters were 1.99 and 3.52 gm at the level of control and 1.77 and 2.13 gm at the level of 350 ppm Cu2+ in cv. Assiut 84 and cv. Assiut 125, respectively. This contradiction was also extended when these copper-affected cultivars were sprayed by IAA. The cv. Assiut 84 responded slightly to IAA treatment. On the other hand, a considerable increase in the dry matter yield was recorded in the pods of cv. Assiut 125 at any used level of copper when compared to the non-sprayed plants treated by the same copper concentration. At the level of 350 ppm Cu2+ , the pod yield was 2-fold that of plants treated only by 350 ppm Cu2+ , without IAA spraying. Thus, even IAA behaved differently in its effect on the crop yield of the two tested broad bean cultivars. There are big and surprising variations in the accumulation of microelements and heavy metals in pods among the two broad bean genotypes, whatever the treatments used. These variations seemed to be complicated which might need further studies. The concentration of amino acids and their individuals also varied among the two cultivars;they increased in cv. Assiut 84 and decreased in cv. Assiut 125. The increased amino acids in cv. Assiut 84 are mostly used as precursors for phytochelatins. For the previous studies, thus the present work was conducted to explain the effect of Cu and interactive effect with IAA on two selected broad bean cultivars Assiut 84 and Assiut 125 during yielding production. 展开更多
关键词 Synergistic effect amino acids Microelement BROAD BEAN CULTIVARS
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The Effect of Ethanol on the Transport of a Neutral Amino Acid in the Perfused Whole Human Placenta
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作者 Tai J. Kim Philip A. Rice 《Journal of Biomedical Science and Engineering》 2019年第2期121-150,共30页
The effect of ethanol on the transport of amino acids across the human placenta was studied in the dual perfusion apparatus using a non-metabolizable α-amino isobutyric acid (AIB). Results were obtained for thirty in... The effect of ethanol on the transport of amino acids across the human placenta was studied in the dual perfusion apparatus using a non-metabolizable α-amino isobutyric acid (AIB). Results were obtained for thirty intact whole human placentas in the absence (control group) and presence (ethanol group) of ethanol (500 - 1000 mg/dL). Experimental determinations of AIB transport at AIB concentrations of 5 - 100 mg/l, measured radioactively using (1&#8722;14 C-) AIB, were compared with a dual-active transport model. The diffusion coefficients of AIB were found to be (3.7 × 10&#8722;9 cm2/s) in the absence of ethanol and (2.3 × 10&#8722;9 cm2/s) in the presence of ethanol with no statistical difference (P = 0.25). The ratio of the fetal to maternal perfusate concentrations in the absence of ethanol (1.44) was statistically significant (P = 0.016) from the ratio in the presence of ethanol (1.20), which may indicate that active transport in the human placenta is inhibited by the presence of ethanol. The placental uptake from the maternal circulation was 2.6 (control) and 2.5 (ethanol) times greater than the uptake from the total circulation. The relative contribution of the diffusive transport to the net placental uptake of AIB from both the maternal and fetal circulations was less than that of active transport regardless of the presence of ethanol: control (38%) and ethanol (35%). It appears that the placental tissue plays the role of a mediator to maintain a fetal concentration higher than the maternal one by either enhancing the transfer from the maternal to the placental tissue or impairing the transfer in the opposite direction. 展开更多
关键词 effect ETHANOL TRANSPORT amino acid Human PLACENTA
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Inhibitory effect of PF4 on megakary-opoiesis is dependent on very few amino acid residues of PF4
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《中国输血杂志》 CAS CSCD 2001年第S1期414-,共1页
关键词 acid very Inhibitory effect of PF4 on megakary-opoiesis is dependent on very few amino acid residues of PF4 PF
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Effect of nitric oxide synthase inhibitor N^G-nitro-L-arginine on the content of amino acid in ischemic brain tissues of rats
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作者 Jianxin Zhang Huixin Zhang Lanfang Li Qinzeng Zhang Yonghui Li 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第4期309-312,共4页
BACKGROUND: Nitric oxide synthase (NOS) inhibrtors have been widely used to investigate the role of NO on cerebral ischemic injury, but the results are controversial. Moreover, it has been considered to aggravate t... BACKGROUND: Nitric oxide synthase (NOS) inhibrtors have been widely used to investigate the role of NO on cerebral ischemic injury, but the results are controversial. Moreover, it has been considered to aggravate the ischemic neuronal damage with the release of excessively excitatory amino acids (EAA) during cerebral ischemia. On the other hand, some inhibitory amino acid is suggested to be important for the neuronal protection against ischemic brain damage. Our study has recently showed that treatment with the NOS inhibitor NG-nitro-L-arginine (L-NA) reduced focal cerebral ischemic damage. The effect of L-NA on the contents of excitatory and inhibitory amino acid in the rat brain following cerebral ischemia is still unclear. OBJECTIVE: By evaluating the effect of NOS inhibitor, L-NA on the contents of aspartate, glutamate, glycine and γ-aminobutyric acid (GABA) in striatum, hippocampus and cortex in the rat brain following cerebral ischemia respectively, to investigate the beneficial effect of L-NA on cerebral ischemic injury and the possible mechanism. DESIGN: A randomized and controlled experiment SETTING : Department of Pharmacology, Hebei Academy of Medical Sciences MATERIALS: A total of 42 male healthy SD rats (grade Ⅱ, weighting 250-300 g) were provided by the Experimental Animal Center of Hebei Province (Certification: 04036). Aspartate, glutamate, glycine, GABA, L-NA and 2,3,5-triphenyltetrazolium chloride (TTC) were obtained from Sigma Chemicals Co, St Louis, MO, USA. HPLC-ultraviolet detector system consisted of Agilent 1100 HPLC. METHODS: The experiment was carried out in Department of Pharmrcology, Hebei Academy of Medical Sciences from June 2005 to June 2006. Rats were randomly divided into three groups: sham-operated group (n = 6), ischemic group (n = 18), L-NA group (n = 18). The model of focal cerebral ischemia in rat was prepared with intraluminal line occlusion methods. In sham-operated rats, the external carotid artery was surgically prepared, but the filament was not inserted. Each group was further divided into 3 subgroups (n = 6 for each): drugs were administrated at 2, 6 and 12 hours after the middle cerebral artery occlusion (MCAO) respectively. L-NA (20 mg/kg, ip) was administrated, twice a day, for 3 consecutive days. Same volume of normal saline was administrated in ischemic and sham operation groups. The changes of infarcted volume and the contents of amino acids were respectively assayed. Image analysis software was used for the measurement of the infarcted area. The results were expressed as a percentage of the infarcted volume of cerebral/volume of whole brain (IV%) in order to control for edema formation. The contents of aspartate, glutamate, glycine and GABA in striatum, hippocampus and cortex in the rat brain following cerebral ischemia were respectively measured by HPLC method. All data were analyzed with one-way ANOVA and Dunnett's test. MAIN OUTCOME MEASURES: (1) The volume of cerebral infarction; (2) The contents of aspartate, glutamate glycine and GABA in brain tissue after cerebral ischemia. RESULTS : All 42 rats were involved in the final analysis. (1) Infarcted volume: Volume was 0 in sham-operated group. When L-NA was administrated at 2 and 6 hours after MCAO, the infarcted volume was (20.13±3.59)% and (23.12±5.84)% in L-NA group, which was not similar to that in ischemic group [(22.10±3.98)%, (25.38± 5.37)%, P〉 0.05]. However, the infarcted volume was markedly decreased compared with that of ischemic group when L-NA was administrated at 12 hours after MCAO [(26.11±3.55)% and (37.15±3.58)%, P 〈 0.01]. Changes of amino acid content: At 2 and 6 hours after ischemia, the contents of aspartate, glutamate, glycine and GABA in striatum, hippocampus and cortex in ischemic group were significantly increased compared with those in sham-operated group ( P〈 0.05-0.01). However, contents in L-NA group were similar to those in ischemic group (P 〉 0.05). At 12 hours after ischemia, the contents of aspartate [(0.21 ±0.06), (0.36±0.05), (0.29±0.12) mg/g] and glutamate [(0.55±0.06), (0.78±0.10), (0.52±0.10) mg/g] in striatum, hippocampus and cortex in L-NA group were significantly decreased compared with those in ischemic group [(0.49±0.17), (0.63± 0.03), (0.51±0.15) mg/g; (0.98±0.30), (1.15±0.15), (0.93±0.15) mg/g, P〈 0.05-0.01]. Glycine in hippocampus was (0.40±0.07) mg/g, which was higher than that in ischemic group [(0.21±0.07) mg/g, P 〈 0.05]. GABA in striatum, hippocampus and cortex was (0.93±0.10), (0.62±0.12) and (0.81 ±0.10) mg/g, respectively, which was higher than that in ischemic group [(0.60±0.08), (0.37±0.17), (0.59±0.10) mg/g, P 〈 0.05-0.01]. CONCLUSION : It may be concluded that L-NA have beneficial effect on ischemic cerebral injury in ischemic later stage in rats. The possible mechanism is that L-NA can decrease the contents of aspartate and glutamate, increase the contents of glycine and GABA. 展开更多
关键词 acid effect of nitric oxide synthase inhibitor N^G-nitro-L-arginine on the content of amino acid in ischemic brain tissues of rats
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Soil inorganic amendments produce safe rice by reducing the transfer of Cd and increasing key amino acids in brown rice
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作者 Fanyi Kong Shenggao Lu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第2期121-132,共12页
The digestibility of cadmium(Cd)in brown rice is directly related to amino acid metabolism in rice and human health.In our field study,three kinds of alkaline calcium-rich soil inorganic amendments(SIAs)at three dosag... The digestibility of cadmium(Cd)in brown rice is directly related to amino acid metabolism in rice and human health.In our field study,three kinds of alkaline calcium-rich soil inorganic amendments(SIAs)at three dosages were applied to produce safe rice and improve the quality of rice in Cd-contaminated paddy.With the increased application of SIA,Cd content in iron plaque on rice root significantly increased,the transfer of Cd from rice root to grain significantly decreased,and then Cd content in brown rice decreased synchronously.The vitro digestibility of Cd in brown rice was estimated by a physiologically based extraction test.Results showed that more than 70%of Cd in brown rice could be digested by simulated gastrointestinal juice.Based on the total and digestible Cd contents in brown rice to evaluate the health risk,the application of 2.25 ton SIA/ha could produce safe rice in acidic slightly Cd-contaminated paddy soils.The amino acids(AAs)in brown rice were determined by high-performance liquid chromatography.The contents of 5 key AAs(KAAs)that actively respond to environmental changes increased significantly with the increased application of SIA.The structural equation model indicated that KAAs could be affected by the Cd translocation capacity from rice root to grain,and consequently altered the ratio of indigestible Cd in brown rice.The formation of indigestible KAAs-Cd complexes by combining KAAs(phenylalanine,leucine,histidine,glutamine,and asparagine)with Cd in brown rice could be considered a potential mechanism for reducing the digestibility of Cd. 展开更多
关键词 Cadmium digestibility Soil inorganic amendments Safe rice amino acid Priming effect Health risk
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The Combined Effects of High Temperature and Carbon Monoxide on Heat Stress Response 被引量:2
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作者 邬堂春 贺涵贞 +4 位作者 吴扬 徐代根 屈伸 冯家德 张国高 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1995年第3期178-183,共6页
In this study,we have examined the effects of exposure to high temperature, carbon inonoxideor a combination of both conditions in a model system,the rat and in industrial workers.In the rat liver, HSP70 mRNA and HSP7... In this study,we have examined the effects of exposure to high temperature, carbon inonoxideor a combination of both conditions in a model system,the rat and in industrial workers.In the rat liver, HSP70 mRNA and HSP70 synthesis were measured by dot hybridization and western blot. The results showed that after a heat stress HSP70 mRNA and its product, HSP70 increased significantly and there was a synergism in the combined effects of high temperature and carbon monoxide exposure on the induction of HSP70 mRNA and HSP70 synthesis. Heat played a major role in this induction. The presence of antibodies to human HSP27, HSP60, HSP70,HSC73, HSP89 αand β in workers exposed to heat, carbon monoxide was also measured by western blot using purified HSPs as antigens. Plasma free amino acids were measured in the saine group of workers. The incidence of antibodies to HSP27 and HSP70 Was significantly higher in the workers working in an environment with extreme heat, and high carbon monoxide ernission than in a control group. The carbon monoxide exposed group showed the highest incidence of antibodies to HSPs. Although our previous results indicated that workers had an insufficient protein intake,plasma free amino acids tended to increase, especially in methionine and tryptophan two kinds of amino acids which are absent from the main stress protein, HSP70.These results suggest that the major problems that these workers may face are how to facilitate the use of plasma free amino acids and reduce the inhibition of synthesis of normal proteins when they are exposed to occupational harmful factors.These resultsalso add new information on the measurement of HSPs as a potential biomonitor to assess whether organisms are experiencing metabolic stress within their environment. 展开更多
关键词 high temperature4 carbon monoxide the combined effects HSP70 HSP70 mRNA antibodies to heat stress proteins plasma free amino acids
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Effects of Diet on the Volatile Flavor and Nutritional Ingredients of Common Octopus(Octopus vulgaris) 被引量:1
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作者 LUO Qihao WANG Weijun +5 位作者 LI Zan ZHU Xinghua WANG Xue ZHANG Tonghua XU He YANG Jianmin 《Journal of Ocean University of China》 SCIE CAS CSCD 2021年第2期393-401,共9页
Cephalopods are important economic shellfish that have been developed extensively in the coastal water of various countries. Octopus vulgaris is a large-scaled economic cephalopod that is mainly cultured in South Chin... Cephalopods are important economic shellfish that have been developed extensively in the coastal water of various countries. Octopus vulgaris is a large-scaled economic cephalopod that is mainly cultured in South China. This study explored the effect of different diets on the volatile flavor and nutritional ingredients of O. vulgaris. Four diets were tested in four groups: Group A(fish(Scomberomorus niphonius)), Group B(crab(Helice tridens tientsinensis Rathbun)), Group C(clam(Mactra veneriformis)), and Group D(squid(Loligo japonica)). Octopus muscles were sampled after 36 days of feeding, and volatile flavor substances(VFSs), fatty acids(FAs), and amino acids(AAs) were detected. Results showed that the VFSs, FAs, and AAs of octopus in the four groups were obviously different. The sum of volatile ketones and aldehydes was higher in Group B than in the other groups, which could present much more flavors. All groups were abundant in unsaturated FAs, including eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA). In terms of content and variety, the FAs in Group B were more beneficial to human health than those in the other groups. The content of each AA in Group B was basically higher than those in the other groups and was significantly higher than that in Group D(P < 0.05). Comparing the VFSs, FAs, and AAs in samples fed with four kinds of diets, the results indicate that using crab to feed O. vulgaris can achieve better effects on volatile flavor and nutritional ingredients. 展开更多
关键词 Octopus vulgaris volatile flavor substances fatty acids amino acids diet effect
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Novel therapeutic approaches targeting L-type amino acid transporters for cancer treatment 被引量:3
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作者 Keitaro Hayashi Naohiko Anzai 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2017年第1期21-29,共9页
L-type amino acid transporters(LATs) mainly assist the uptake of neutral amino acids into cells. Four LATs(LAT1, LAT2, LAT3 and LAT4) have so far been identified. LAT1(SLC7A5) has been attracting much attention in the... L-type amino acid transporters(LATs) mainly assist the uptake of neutral amino acids into cells. Four LATs(LAT1, LAT2, LAT3 and LAT4) have so far been identified. LAT1(SLC7A5) has been attracting much attention in the field of cancer research since it is commonly up-regulated in various cancers. Basic research has made it increasingly clear that LAT1 plays a predominant role in malignancy. The functional significance of LAT1 in cancer and the potential therapeutic application of the features of LAT1 to cancer management are described in this review. 展开更多
关键词 LAT1 氨基酸 transporter 分子的目标药 氨基酸饥饿反应 信号 transduction
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The Properties of Nanohydroxyapatite Materials and its Biological Effects 被引量:1
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作者 Xiaofeng Pang Hongjuan Zeng +2 位作者 Jialie Liu Shicheng Wei Yufeng Zheng 《Materials Sciences and Applications》 2010年第2期81-90,共10页
The nanohydroxyapatites (HAP) and its biological effects have been studied using ultraviolet absorption spectrum, X-ray diffraction (XRD) structure analysis, fluorescent and infrared spectrum of absorption and MTT met... The nanohydroxyapatites (HAP) and its biological effects have been studied using ultraviolet absorption spectrum, X-ray diffraction (XRD) structure analysis, fluorescent and infrared spectrum of absorption and MTT method. The nanohyd- roxyapatites are prepared and made by using Sol-gel method, in which the parameters of process and reaction are controlled as: PH 】9, Ca/P = 1.67, sintering temperature of 1100?C and sintering time 2 hours. The results of the study show that nanohydroxyapatites can absorb the amino acid molecules, the absorption is better for stronger acidity of amino acids. We also find that the nanohydroxyapatites and complex of nanoHAP+ nanoCrO2 can all restrain the proliferation of cells, but their toxiciteis are all first degree or minor, but the restrained effect of the latter is smaller than that of the former, although they can decrease the relative proliferation rate of cells. The nanohydroxyapatites can also change the molecular structure of human serum albumin. 展开更多
关键词 Nanohydroxyapatite CELL BIOLOGICAL effect TOXICITY amino acids SOL-GEL
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Cu(Ⅱ)-L-amino acid-O-phen体系的园二色性研究
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作者 杨弘 谷如驹 赵永德 《郑州轻工业学院学报》 1993年第3期48-52,共5页
室温下,水溶液中测定了Cu(Ⅱ)-L-amino acid-O-phen(1∶1∶1)体系的园二色谱。根据750~200nm光谱内的Cotton效应,确定了测量条件下络合物的绝对构型。发现在260~320nm胱氨酸和色氨酸的园二色谱带符合三齿配体结构;而亮氨酸、谷氨酸、... 室温下,水溶液中测定了Cu(Ⅱ)-L-amino acid-O-phen(1∶1∶1)体系的园二色谱。根据750~200nm光谱内的Cotton效应,确定了测量条件下络合物的绝对构型。发现在260~320nm胱氨酸和色氨酸的园二色谱带符合三齿配体结构;而亮氨酸、谷氨酸、赖氨酸和精氨酸的络合物在这段光谱内无上述现象,从而确定为二齿配体结构。 展开更多
关键词 园二色性 氨基酸 络合物 构型
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伏诺拉生不良反应研究进展
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作者 姜立根 卢增珍 +1 位作者 杨柳 刘华一 《实用药物与临床》 CAS 2024年第4期297-303,共7页
伏诺拉生是新型的抑酸药物,药理作用与质子泵抑制剂不同,抑酸作用较质子泵抑制剂可能更为强大、持久。随着伏诺拉生临床应用时间和病例数的增加,不良反应报道也逐渐增多,同时随着临床药理研究的深入,伏诺拉生潜在的不良反应也逐渐呈现... 伏诺拉生是新型的抑酸药物,药理作用与质子泵抑制剂不同,抑酸作用较质子泵抑制剂可能更为强大、持久。随着伏诺拉生临床应用时间和病例数的增加,不良反应报道也逐渐增多,同时随着临床药理研究的深入,伏诺拉生潜在的不良反应也逐渐呈现。本文通过检索文献,了解伏诺拉生抑酸作用导致的潜在不良反应,以及伏诺拉生与其他药物联合应用时可能出现的潜在不良反应。 展开更多
关键词 伏诺拉生 药物不良反应 抑酸作用 药物相互作用
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