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1.
Ying Yong Sheng Tai Xue Bao ; 31(3): 744-752, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32537968

RESUMO

Urban forest is an important carbon pool, soil respiration of which is an important part of terrestrial carbon cycle. To understand the dynamics and influencing factors of soil respiration in urban forest under the background of increasing nitrogen deposition, we conducted dynamic observation on soil respiration rate, temperature, moisture and chemical properties by adding 0 (CK), 50 (LN), 100 (HN) kg N·m-2·a-1 ammonium nitrate to a typical urban forest. The results showed that soil respiration had significant seasonal variation, which was not affected by nitrogen addition. Soil respiration was significantly correlated with soil temperature. The interaction between soil temperature and soil moisture could better explain the variation of soil respiration. Nitrogen addition changed temperature sensitivity of soil respiration, with the order of Q10 values as LN (2.12) > CK (2.10) > HN (2.05). Soil nitrate concentration, soil soluble organic carbon, pH, soil carbon to nitrogen ratio had significant correlation with soil respiration. The positive effect of nitrogen deposition on soil respiration was mainly in the growing season, with slightly inhibitive effect in the non-growing season.


Assuntos
Nitrogênio , Solo , Ciclo do Carbono , China , Florestas , Temperatura
2.
DNA Cell Biol ; 36(11): 1010-1017, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28972393

RESUMO

Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that interacts with multiple signaling pathways during prostate development. In the present study, LNCaP cells were knocked down of AhR by siRNA, or treated with the AhR agonist 3-methylcholanthrene (3MC). The effects of AhR on LNCaP cells and the associated mechanisms were studied both under normal condition and under hydrogen peroxide (H2O2)-induced oxidative stress. MTT, transwell chamber assays and flow cytometry were employed to investigate cell proliferation, invasion, and apoptosis, respectively, whereas the DNA damage response (DDR) signaling (phosphorylation of ataxia-telangiectasia mutated [ATM], check-point kinase 2 [Chk2], histone H2AX, p53, and cleaved poly-ADP-ribose polymerase [PARP]) was detected by western blotting. Exposure of LNCaP cells to H2O2 inhibited their viability and migration, and induced apoptosis, at a greater extent compared with the culture under normal conditions. In addition, the oxidative stress increased p-ATM, p-Chk2, p-p53, and p-H2AX expression levels significantly. Knockdown of AhR attenuated the aforementioned effects caused by H2O2-induced oxidative stress. Activation of AhR by 3MC treatment, further aggravated these changes of LNCaP cells on oxidative stress. The findings indicated that AhR suppresses the viability and migration of LNCaP cells notably under oxidative stress, and this process is associated with positive regulation of the responses to oxidative DNA damage.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Movimento Celular , Proliferação de Células , Dano ao DNA , Estresse Oxidativo , Neoplasias da Próstata/patologia , Receptores de Hidrocarboneto Arílico/metabolismo , Apoptose , Fatores de Transcrição Hélice-Alça-Hélice Básicos/antagonistas & inibidores , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Humanos , Peróxido de Hidrogênio/farmacologia , Masculino , Oxidantes/farmacologia , Fosforilação , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Receptores de Hidrocarboneto Arílico/genética , Células Tumorais Cultivadas
3.
Food Chem ; 194: 1245-53, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26471678

RESUMO

A novel "hyperactive" ice-binding peptide from porcine collagen was prepared by alkaline protease hydrolysis and a series of column chromatography separations, and then its antifreeze and cryoprotective properties were reported. Using differential scanning calorimetry (DSC), the thermal hysteresis (TH) of ice-binding collagen peptides was closely related to their concentration and crystal fraction. Collagen hydrolysates with maximal TH were obtained by hydrolysis at pH 8.0, DH 15.0%, and 5% alkaline protease at 55°C. After purification by column chromatography, the AP-3 ice-binding collagen peptide (GLLGPLGPRGLL) with 1162.8Da molecular weights exhibited the highest TH (5.28°C), which can be classified as "hyperactive". Recrystallisation and melt-resistance of ice cream were improved by AP-3 ice-binding collagen peptide at 0.2% (w/v) in a similar manner to natural antifreeze proteins. Moreover, the addition of AP-3 collagen peptides in ice cream greatly elevated the glass transition temperature (Tg) to -17.64°C.


Assuntos
Colágeno/química , Crioprotetores/química , Peptídeos/química , Pele/química , Animais , Proteínas de Bactérias/química , Varredura Diferencial de Calorimetria , Endopeptidases/química , Hidrólise , Gelo , Ligação Proteica , Suínos
4.
Chin Med J (Engl) ; 126(15): 2834-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23924452

RESUMO

BACKGROUND: Endostatin is a potent inhibitor of tumor angiogenesis. In the preliminary studies, we developed a mutant endostatin containing Arg-Gly-Asp-Arg-Gly-Asp (RGDRGD) sequences. In this study, we compared the antitumor effects of mutant endostatin and Bcl-2 antisense oligonucleotides both in combination and individually. METHODS: The artificially synthesized Bcl-2 ASODN (antisense oligonucleotides) included a translation-initiation site and was transfected into the bladder cancer cells by Lipofectamine. Cell growth was investigated by the tumor cell growth chart, MTT assay, caspase-3 activity detection assay, AO/EB fluorescein stain, and the annexin V-FITC apoptosis detection assay. In the in vivo study, UM-UC-3 bladder cancer cells were subcutaneously implanted into nude mice and the growth of tumor was examined. The ultrastructure of the tumor tissues in the treated and control groups were observed. RESULTS: The cell growth chart showed that the cell population of the treated combination group decreased by 52.04% compared to the control group. The inhibition rate of the treated combination group was (79.66 ± 6.79)%, whereas those of the individual ASODN and ES groups were (53.39 ± 3.22)% and (50.22 ± 5.46)% respectively. In the caspase-3 activity detection using AO/EB fluorescein stain and annexin V-FITC apoptosis detection assay, the co-inhibitory effect was higher than the individual inhibitory effects (P < 0.05). There were significant differences in the inhibition of the solid tumor growth in the in vivo study. CONCLUSIONS: Our findings indicated that Bcl-2 antisense oligonucleotides enhance the antitumor effects of mutant endostatin both in vitro and in vivo. We noted the synergistic effects of Bcl-2 antisense oligonucleotides combined with mutant endostatin.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Endostatinas/administração & dosagem , Tionucleotídeos/administração & dosagem , Neoplasias da Bexiga Urinária/patologia , Animais , Linhagem Celular Tumoral , Sinergismo Farmacológico , Camundongos
5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-343695

RESUMO

<p><b>OBJECTIVE</b>To observe the effects of subchronic benzo[a]pyrene (B[a]P) exposure on the neurobehavior and hippocampal acetylcholine (Ach) level, acetylcholinesterase (AChE) activity, and mRNA and protein expression of nicotinic acetylcholine receptor α7 subtype (nAChR α7) in rats, and to investigate the neurotoxic mechanism of B[a]P.</p><p><b>METHODS</b>Sixty healthy male SD rats were randomly divided into blank control group, solvent control group, and B [a]P exposure groups. Each rat in the exposure groups was intraperitoneally injected with B[a]P at 1.0, 2.5, or 6.25 mg/kg once every other day for 90 days. The learning and memory ability of the rats was examined by Morris water maze test and step-down test; the hippocampal Ach level was measured by alkaline hydroxylamine method; the AChE activity was measured by DNTB method; the mRNA and protein expression levels of hippocampal nAChR α7 were measured by quantitative PCR and Western blot.</p><p><b>RESULTS</b>The 2.5 and 6.25 mg/kg B[a]P exposure groups showed significantly lower learning and memory abilities than the blank control group and solvent control group (P < 0.05); also, the two groups had significantly lower hippocampal Ach levels than the blank control group, solvent control group, and 1.0 mg/kg B[a]P exposure group (P < 0.05). The 6.25 mg/kg B[a]P exposure group showed significantly lower hippocampal AChE activity than the blank control group, solvent control group, and 1.0 mg/kg B[a]P exposure group (P < 0.05). There were no significant differences in the mRNA and protein expression levels of nAChR α7 among all groups (P > 0.05). The hippocampal Ach level was negatively correlated with the mean escape latency period and total distance travelled (r = -0.567, P < 0.01; r = -0.503, P < 0.01) but positively correlated with the time in platform quadrant (r = 0.800, P < 0.01).</p><p><b>CONCLUSION</b>Subchronic B[a]P exposure may impair the learning and memory ability in rats, which is related to the downregulation of hippocampal Ach level.</p>


Assuntos
Animais , Masculino , Ratos , Acetilcolina , Metabolismo , Acetilcolinesterase , Metabolismo , Benzo(a)pireno , Toxicidade , Hipocampo , Metabolismo , Aprendizagem em Labirinto , Memória , Ratos Sprague-Dawley , Receptores Colinérgicos , Metabolismo , Testes de Toxicidade Subcrônica , Receptor Nicotínico de Acetilcolina alfa7 , Metabolismo
6.
Phytother Res ; 26(2): 204-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21618639

RESUMO

A double-blind parallel group comparison design clinical study was conducted in Japanese patients with mild to moderate erectile dysfunction to investigate the efficacy of a supplement containing Pycnogenol® and L-arginine. Subjects were instructed to take a supplement (Pycnogenol® 60 mg/day, L-arginine 690 mg/day and aspartic acid 552 mg/day) or an identical placebo for 8 weeks, and the results were assessed using the five-item erectile domain (IIEF-5) of the International Index of Erectile Function. Additionally, blood biochemistry, urinalysis and salivary testosterone were measured. Eight weeks of supplement intake improved the total score of the IIEF-5. In particular, a marked improvement was observed in 'hardness of erection' and 'satisfaction with sexual intercourse'. A decrease in blood pressure, aspartate transaminase and γ-glutamyl transpeptidase (γ-GTP), and a slight increase in salivary testosterone were observed in the supplement group. No adverse reactions were observed during the study period. In conclusion, Pycnogenol® in combination with L-arginine as a dietary supplement is effective and safe in Japanese patients with mild to moderate erectile dysfunction.


Assuntos
Arginina/uso terapêutico , Disfunção Erétil/tratamento farmacológico , Flavonoides/uso terapêutico , Adulto , Povo Asiático , Aspartato Aminotransferases/metabolismo , Pressão Sanguínea , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Ereção Peniana , Extratos Vegetais , Testosterona/análise , gama-Glutamiltransferase/metabolismo
7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-260540

RESUMO

<p><b>OBJECTIVE</b>To observe effects of acupuncture on quality of life of patients with chronic fatigue syndrome (CFS).</p><p><b>METHODS</b>Randomized, controlled and single-blinded study method was used, 70 cases were divided into an observation group and a control group, 35 cases in each group. The observation group was treated with acupuncture at Baihui (GV 20), Danzhong (CV 17), Zhongwan (CV 12), Qihai (CV 6), Guanyuan (CV 4), Hegu (LI 4), Zusanli (ST 36), etc.; the control group was treated with acupuncture at non-meridian points (2 cm to the acupoints), thrice a week. The treatment was given for 14 times. The World Health Organization Quality of Life (WHOQOL-BREF) scale was used to evaluate the patients' quality of life before and after treatment.</p><p><b>RESULTS</b>The physiological field, individuals own perception of his health condition and total score were significantly improved after treatment in the observation group (all P<0.05); there were no obvious changes in the psychology, social relationships, environment and subjective feelings about the quality of life (all P>0.05). The score of the environmental field in the control group was significantly decreased compared to that before treatment (P<0.05), and there were no significant changes in the other scores. There were no adverse effects in patients.</p><p><b>CONCLUSION</b>Acupuncture can improve the quality of life of CFS patients, especially in physiological field and the individual perception to his well being. Acupuncture has high safety, and the acupoints has high specific degree than non-meridian points.</p>


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Pontos de Acupuntura , Terapia por Acupuntura , Síndrome de Fadiga Crônica , Psicologia , Terapêutica , Qualidade de Vida
8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-267265

RESUMO

<p><b>OBJECTIVE</b>To probe into the role of Siguan points in treatment of chronic fatigue syndrome.</p><p><b>METHODS</b>Based on diagnosis, pathogenesis and etiology of chronic fatigue syndrome in TCM, the role of Siguan points in treatment of chronic fatigue syndrome were induced by means of relative literatures of Siguan points in recent 10 years from 3 aspects.</p><p><b>CONCLUSION</b>Acupuncture at Siguan as main points has a better therapeutic effect on chronic fatigue syndrome.</p>


Assuntos
Humanos , Pontos de Acupuntura , Terapia por Acupuntura , Síndrome de Fadiga Crônica , Terapêutica
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