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1.
J Nat Prod ; 82(7): 1741-1751, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31268321

RESUMO

Nine new prenylated bibenzyls, radstrictins A-I (1-9), and 11 known congeners were obtained from the Chinese liverwort Radula constricta. Their structures were identified by analysis of HRMS, NMR, and electronic circular dichroism data. Radstrictins A-F (1-6) were isolated as a racemate or scalemic mixtures. All the isolated compounds were subjected to cytotoxicity assessment. Methyl 2,4-dihydroxy-3-(3-methyl-2-butenyl)-6-phenethylbenzoate (10) exhibited significant activity against human lung cancer cell lines A549 and NCI-H1299 with IC50 values of 6.0 and 5.1 µM, respectively. Further research revealed that cell death triggered by 10 occurred via mitochondria-derived paraptosis.

2.
Ying Yong Sheng Tai Xue Bao ; 30(5): 1615-1624, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31107018

RESUMO

The retrogressive succession is an important driver for dynamics of soil organic carbon (SOC) and total nitrogen (TN). We studied the quantitative distribution and synergistic accumulation characteristics of soil organic carbon and nitrogen in the primary broadleaved Korean pine (KP) forest and Betula platyphylla (BP) secondary forest in Changbai Mountain through paired plot approach. Further, we analyzed the changes of carbon pool and carbon sink effect in temperate forest soil caused by secondary succession and their carbon-nitrogen coupling mechanism. The results showed that the BP forest accumulated more organic carbon and nitrogen in the surface and subsurface soil (0-20 cm) than the KP forest, with relatively low soil C/N. Compared with KP forest, soil organic carbon storage in BP forest (0-20 cm) was higher by 14.7 t·hm-2, equivalent to a soil carbon sink gain of 29.4 g·m-2·a-1. SOC and TN concentrations were positively correlated in each soil layer of all forest types, causing a co-accumulative relationship between SOC and TN. The coefficient of determination (R2) between SOC and TN in the upper soil layers of BP forest was significantly higher than that of the KP forest, indicating that SOC accumulation under the relatively N-rich BP forest was more dependent on the accumulation of organic nitrogen. In the upper soil layers (0-10 cm) where organic matter concentrated, there was no significant difference in light fraction organic carbon and nitrogen stock between the two forest types, whereas the content, stock, and allocation percentage of heavy fraction organic carbon and nitrogen of BP forest were all significantly higher than that of the KP forest, with an average increment of 8.5 t·hm-2 in heavy fraction organic carbon stock. Those results indicated that the increase of soil organic carbon and nitrogen during secondary succession was mainly due to the increases of soil organic carbon and nitrogen pools in mineral-bound stability. The carbon-nitrogen coupling mechanisms in litter decomposition and soil organic matter formation was an important driving mechanisms underlying the changes of soil organic carbon and nitrogen pools during secondary succession.


Assuntos
Carbono/análise , Monitoramento Ambiental , Florestas , Nitrogênio/análise , Solo/química , Betula/crescimento & desenvolvimento , China , Pinus/metabolismo
3.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 36(2): 162-166, 2018 Apr 01.
Artigo em Chinês | MEDLINE | ID: mdl-29779277

RESUMO

OBJECTIVE: This study aims to study the effect of the improved partial denture treatment in the rehabilitation of patients with temporomandibular joint disorders (TMD). METHODS: Twenty middle-aged and old patients suffering from osteoarthrosis were treated with the improved partial denture treatment. These patients were followed up during the partial denture treatment and after the rehabilitation. Both the clinical symptoms and Fricton's craniomandibular index were used to evaluate the clinical effects. Data were analyzed using SPSS17.0. RESULTS: The effective rate reached 100% when the patients wore partial dentures for 1 month. All of the 20 patients were comfortable with temporomandibular joint, and they expressed ultimate satisfaction with the denture. The Fricton indexes of 20 patients decreased significantly after the treatment (P<0.05). CONCLUSIONS: Partial denture treatment is an ideal method in rehabilitation for patients with TMD (osteoarthrosis) and dentition defect.

4.
Biomed Mater ; 13(4): 041001, 2018 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-29516867

RESUMO

Understanding the interaction between biomaterials and the immune system has become increasingly important. Mineralized collagen (MC) has the same chemical components and microstructures to natural bone tissue, and is considered as a better biomaterial for bone prostheses compared to hydroxyapatite (HA). However, there is little information about how MC affects inflammatory responses. In this study, we investigate the inflammatory responses to MC and HA by culturing RAW264.7 cells on their surfaces. We observed that MC increases CD206+ staining and IL-10 (M2 macrophages), whereas HA shows cells expressing more CD86 and secreting more TNF-α. This result indicates that MC may attenuate inflammatory responses to implanted bone prostheses.

5.
Environ Sci Pollut Res Int ; 24(35): 27303-27313, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28967049

RESUMO

This study aimed to evaluate the 28 trace elements in the blood and serum antioxidant status in chickens under arsenic (As) and/or copper (Cu) exposure. A total of 200 1-day-old male Hy-Line chickens were fed either a commercial diet (C-group) or arsenic trioxide (30 mg/kg) and/or cupric sulfate (300 mg/kg) for 90 days. The 28 trace element levels in the blood were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The concentrations of As in the blood of chickens were elevated approximately 17.15-fold, 2.30-fold, and 13.37-fold in the As-group, Cu-group, and As + Cu-group, respectively, at 90 days. The concentrations of Cu did not change in the As-group and increased approximately 29.53 and 23.37% in the Cu-group and As + Cu-group, respectively, at 90 days. Moreover, As exposure caused ion profile disorders in the blood, including increased concentrations of Na, Mg, Si, K, Cr, Fe, and Se and reduced B, Ca, Ti, V, Mn, Co, Ni, Zn, Sr, and Mo. Cu exposure increased the contents of Mg, Si, Ca, Ti, V, Cr, Mn, Fe, Co, Zn, and Se and decreased the content of B, Ca, Al, Ni, and Mo. As + Cu exposure increased the contents of Mg, Si, Cr, Fe, Zn, and Se and decreased the content of B, Ca, Ti, Co, Ni, Sr, and Mo. Moreover, As and/or Cu exposure induced oxidative stress in the blood of chickens. In conclusion, the results indicated that the mixture of As and Cu caused a synergistic effect via disturbing homeostasis of trace elements and oxidative stress in the blood of chickens.


Assuntos
Antioxidantes/metabolismo , Arsenicais/efeitos adversos , Galinhas/metabolismo , Sulfato de Cobre/efeitos adversos , Óxidos/efeitos adversos , Oligoelementos/sangue , Animais , Arsênico/efeitos adversos , Trióxido de Arsênio , Cobre/efeitos adversos , Dieta , Masculino , Distribuição Aleatória
6.
Ecotoxicol Environ Saf ; 144: 430-437, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28666216

RESUMO

The contents of 28 trace elements, 17 amino acid were evaluated in muscular tissues (wings, crureus and pectoralis) of chickens in response to arsenic trioxide (As2O3). A total of 200 one-day-old male Hy-line chickens were fed either a commercial diet (C-group) or an As2O3 supplement diet containing 7.5mg/kg (L-group), 15mg/kg (M-group) or 30mg/kg (H-group) As2O3 for 90 days. The elements content was analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Under As2O3 exposure, the concentration of As were elevated 8.87-15.76 fold, 7.93-15.63 fold and 5.94-12.45 fold in wings, crureus and pectoralis compared to the corresponding C-group, respectively. 19 element levels (lithium (Li), magnesium (Mg), aluminum (Al), silicon (Si), kalium (K), vanadium (V), chromium (Cr), manganese (Mn), nickel (Ni), copper (Cu), selenium (Se), strontium (Sr), molybdenum (Mo), cadmium (Cd), tin (Sn), antimony (Sb), barium (Ba), mercury (Hg) and lead (Pb), 9 element levels (K, Co, Ni, Cu, As, Se, Sr, Sn, Ba and Hg) and 4 element levels (Mn, cobalt (Co), As, Sr and Ba) were significantly increased (P < 0.05) in wing, crureus and pectoralis, respectively. 2 element levels (sodium (Na) and zinc (Zn)), 5 element levels (Li, Na, Si, titanium (Ti and Cr), 13 element levels (Li, Na, Mg, K, V, Cr, iron (Fe), Cu, Zn, Mo, Sn, Hg and Pb) were significantly decreased (P < 0.05) in wing muscle, crureus and pectoralis, respectively. Additionally, in crureus and pectoralis, the content of total amino acids (TAA) was no significant alterations in L and M-group and then increased approximately 10.2% and 7.6% in H-group, respectively (P < 0.05). In wings, the level of total amino acids increased approximately 10% in L-group, whereas it showed unchanged in M and H-group compared to the corresponding C-group. We also observed that significantly increased levels of proline, cysteine, aspartic acid, methionine along with decrease in the tyrosine levels in muscular tissues compared to the corresponding C-group. In conclusion, the residual of As in the muscular tissues of chickens were dose-dependent and disrupts trace element homeostasis, amino acids level in muscular tissues of chickens under As2O3 exposure. Additionally, the response (trace elements and amino acids) were different in wing, thigh and pectoral of chick under As2O3 exposure. This study provided references for further study of heavy metal poisoning and may be helpful to understanding the toxicological mechanism of As2O3 exposure in muscular tissues of chickens.


Assuntos
Aminoácidos/análise , Ração Animal/análise , Galinhas/metabolismo , Músculos/metabolismo , Óxidos/toxicidade , Oligoelementos/análise , Aminoácidos/metabolismo , Ração Animal/toxicidade , Animais , Trióxido de Arsênio , Arsenicais , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Masculino , Músculos/química , Análise Espectral , Oligoelementos/metabolismo
7.
Ecotoxicology ; 26(8): 1078-1088, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28755286

RESUMO

To evaluate the toxicity of arsenic trioxide (As2O3) in the muscular tissues (wing, thigh and pectoral) of birds, 72 one-day-old Hy-line cocks were selected and randomly divided into four groups. They were fed either a commercial diet or an arsenic-supplemented diet containing 7.5, 15 or 30 mg/kg As2O3. The experiment lasted for 90 days and the samples of muscular tissues were collected at 30, 60 and 90 days. The results showed that As2O3 exposure significantly lowered the activities of antioxidant enzymes (catalase (CAT), glutathione peroxidase (GSH-Px)) and inhibition ability of hydroxyl radicals (OH) and increased the malondialdehyde (MDA) contents. Furthermore, the mRNA levels of inflammatory cytokines (tumor necrosis factor-α (TNF-α), nuclear factor-kappa B (NF-κB), cyclooxygenase-2 (COX-2), inducible NO synthase (iNOS), prostaglandin E synthase (PTGEs)) and heat shock proteins (HSPs) in muscular tissue were significantly upregulated in the As2O3 exposure groups. The results indicated that As2O3 exposure resulted in oxidative damage, induced the inflammatory response, and influenced the mRNA levels of HSPs in muscular tissue of cocks. Additionally, the results suggested that HSPs possibly resisted due to the As2O3 exposure-induced oxidative stress and inflammatory response, which provided a favorable environment and played protective roles in the muscular tissues of cocks. The information presented in this study is helpful to understand the mechanism of As2O3 toxicity in bird muscular tissues.


Assuntos
Galinhas/fisiologia , Substâncias Perigosas/toxicidade , Proteínas de Choque Térmico/metabolismo , Músculos/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Óxidos/toxicidade , Animais , Trióxido de Arsênio , Arsenicais , Biomarcadores/metabolismo , Catalase/metabolismo , Citocinas/metabolismo , Glutationa Peroxidase/metabolismo , Malondialdeído/metabolismo , Músculos/metabolismo , NF-kappa B
8.
J Hazard Mater ; 337: 208-216, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28525881

RESUMO

Two different synthetic methods, the direct method and the substitution method, were used to synthesize the Cs-POM@MOF-199@MCM-41 (Cs-PMM), in which the modified heteropolyacid with cesium salt has been encapsulated into the pores with the mixture of MOF and MCM-41. The structural properties of the as-prepared catalysts were characterized using various analytical techniques: powder X-ray diffraction, FT-IR, SEM, TEM, XPS and BET, confirming that the Cs-POM active species retained its Keggin structure after immobilization. The substitution method of Cs-PMM exhibited more excellent catalytic performance for oxidative desulfurization of dibenzothiophene in the presence of oxygen. Under optimal conditions, the DBT conversion rate reached up to 99.6% and could be recycled 10 times without significant loss of catalytic activity, which is mainly attributed to the slow leaching of the active heteropolyacid species from the strong fixed effect of the mixture porous materials.

9.
Environ Sci Pollut Res Int ; 24(6): 5781-5790, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28054265

RESUMO

The aim of this study was to assess the effects of arsenic trioxide (As2O3) in the chicken heart, and 72 1-day-old male Hy-line chickens were fed either a commercial diet (C group) or an arsenic supplement diet containing 7.5 mg/kg (L group), 15 mg/kg (M group), or 30 mg/kg (H group) As2O3 for 90 days. The results showed that exposure to As2O3 merely lowered (P < 0.05) the activities of catalase (CAT) and glutathione peroxidase (GSH-Px) in M and H groups at 90 days, significantly downregulated the inhibition ability of hydroxyl radicals (OH·), and upregulated (P < 0.05) the contents of malondialdehyde (MDA) in As2O3 exposure groups at 30, 60, and 90 days. Meanwhile, the messenger RNA levels of inflammatory cytokines (tumor necrosis factor-α (TNF-α), nuclear factor-kappa B (NF-κB), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and prostaglandin E synthase (PTGEs)) significantly increased (P < 0.05) in As2O3 exposure groups at 30, 60, and 90 days, and histological and ultrastructural damage was observed in As2O3 exposure groups. Additionally, As2O3-induced cardiac enzyme (aspartate transaminase (AST), creatine kinase (CK), creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), and α-hydroxybutyrate dehydrogenase (α-HBDH)) levels increased (P < 0.05) at 90 days. These findings suggested that As2O3 exposure led to oxidative stress, inflammatory response, and histological and ultrastructural damage and altered the levels of cardiac enzymes in chicken heart tissues. This result may be helpful for further studies on the toxicological mechanisms of As2O3 in the chicken heart.


Assuntos
Galinhas , Coração , Óxidos/toxicidade , Animais , Arsênico , Trióxido de Arsênio , Arsenicais , Catalase , Citocinas , Glutationa Peroxidase , Hidroxibutirato Desidrogenase , Masculino , Malondialdeído , NF-kappa B , Óxido Nítrico Sintase Tipo II , Estresse Oxidativo , Fator de Necrose Tumoral alfa
10.
Ying Yong Sheng Tai Xue Bao ; 27(5): 1628-1638, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-29732826

RESUMO

The objective of this study was to evaluate the molecular characteristics of heat shock protein 70 (HSP70) gene, and document changes in HSP70 gene expression upon exposure of Perinereis aibuhitensis to aqueous Cu2+. Full length cDNA of HSP70 was sequenced and the characteristics of the translated protein were determined and compared both with other ragworms species and other invertebrates. The results showed that the cDNA was 2161 bp and consisted of a 5'-terminal untranslated region (UTR) of 48 bp, a 3'-termianl UTR of 142 bp with a canonical polyadenylation signal sequence AATAAA and a poly A tail, and an open reading frame (ORF) of 1971 bp. The HSP70 protein was 656 amino acids with a calculated molecular weight of 71.43 kD and theore-tical isoelectric point of 5.15. Sequence analysis of the protein showed that HSP70 of P. aibuhitensis contained three signature sequences IDLGTTYS, IFDLGGGTFDVSIL and IVLVGGSTRIPKIQK all belonging to the HSP70 family, a cytoplasm characteristic motif of EEVD, and the C-terminal repeats of GGMP. The molecular characteristics of P. aibuhitensis shared 94% identity with other ragworms and 79% identity with other invertebrates. In ragworms exposed to Cu2+, expression of HSP70 mRNA increased significantly with Cu2+ concentration (0.2-5.0 mg·L-1), and it reached the peak on 1-day exposure. In summary, the molecular characteristics of HSP70 of P. aibuhitensis were described, and its gene expression was inducible by exposure to aqueous Cu2+, suggesting HSP70 has potential to become a useful molecular biomarker of environmental pollution.


Assuntos
Proteínas de Choque Térmico HSP70/genética , Poliquetos/genética , Sequência de Aminoácidos , Animais , Clonagem Molecular , DNA Complementar , Filogenia , RNA Mensageiro
11.
J Colloid Interface Sci ; 460: 8-17, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26310952

RESUMO

A series highly efficient and stable metallophthalocyanine/La0.8Ce0.2NiO3 (ML/LCNO) photocatalysts were prepared by a facile sol-gel and immersion method. The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), TEM, N2 adsorption-desorption, and UV-Vis. The results revealed that LCNO calcined at 700°C possessed a perovskite structure with porous, and phthalocyanine not only adsorbed on the surface but also loaded in the pores of the LCNO oxide. The photocatalytic activities of the samples were evaluated by the photocatalytic oxidation of dibenzothiophene (DBT) under simulated sunlight irradiation. It was found that either macrocyclic structure or center metal of phthalocyanine had great influences on the photocatalytic activity of ML/LCNO. The oxidative reactivity of the different macrocycles was found in the order of MPc/LCNO>MTAP/LCNO>MPTpz/LCNO; which of different center metals was CoL/LCNO>FeL/LCNO>MnL/LCNO>NiL/LCNO>CuL/LCNO. The catalysts were reused several times with a slight decrease in activity. Furthermore, this kinetics of photocatalytic oxidation of DBT indicated that the reaction was a pseudo-first-order reaction.

12.
Artigo em Chinês | MEDLINE | ID: mdl-15283260

RESUMO

OBJECTIVE: To study the prophylactic effect of artesunate against the infection of Schistosoma mansoni in mice and its optimal scheme for preventing schistosomiasis mansoni. METHODS: BALB/c mice were infected by tail dipping method with S. mansoni cercariae. Mice were administered orally with artesunate at different developmental stage of the parasite, with different regimens. The reduction rates of total and female worms, the number of eggs in the liver and intestine, and the fecundity were calculated and treated statistically. RESULTS: The optimal dosage of artesunate to prevent murine schistosomiasis was 300 mg/kg. The parasite was found to be especially susceptible to artesunate in its schistosomula stage of 14 and 21 d after infection, resulting in worm reduction rate of 84% and 93% respectively compared with control. High protection was reached with worm reduction rate of 99% by the regimens of 300 mg/kg once a week for 4 consecutive weeks beginning 14 d after infection. The fecundity was significantly suppressed, suggesting that the drug inhibited sexual maturation of female worms. The effective protection could also be gained with prolonged interval time of two weeks with worm reduction rate of 97% and 96% beginning 14 or 21 d after infection. CONCLUSION: Artesunate kills schistosomula and reduces the fecundity of females effectively, the infected mice do not develop schistosomiasis mansoni when treated with artesunate. It's proposed that an optimal scheme for field use be the first administration 14 or 21 days after infection with 1 or 2 weeks interval.


Assuntos
Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose mansoni/prevenção & controle , Sesquiterpenos/uso terapêutico , Animais , Artesunato , Feminino , Camundongos , Camundongos Endogâmicos BALB C
13.
Artigo em Chinês | MEDLINE | ID: mdl-12884628

RESUMO

OBJECTIVE: To observe the efficacy and side effects of ivermectin in the treatment of intestinal nematode infections. METHODS: A single dose of ivermectin 0.1, 0.2, 0.2 and 0.2 mg/kg was orally administered to cases with infection of Ascaris, hookworm, Trichuris and Enterobius respectively. A single dose of albendazole 400 mg was used as control. RESULTS: The egg negative conversion rates of ivermectin and albendazole were both 100% (34/34) for Ascaris infection, 17.6% (6/34) and 76.5% (26/34) respectively for hookworm infection, 67.6% (23/34) and 47.1% (16/34) respectively for Trichuris infection, 58.8% (20/34) and 100% (34/34) respectively for Enterobius infection. The worm discharge reached a peak in 1-2 days after treatment. The side effect of ivermectin was mild and transient showing no adverse effect on blood picture, liver function, renal function or ECG. CONCLUSION: Ivermectin shows similar effect on Ascaris with albendazole, better effect on Trichuris and poorer effect on hookworm and Enterobius than albendazole.


Assuntos
Antinematódeos/uso terapêutico , Enteropatias Parasitárias/tratamento farmacológico , Ivermectina/uso terapêutico , Infecções por Nematoides/tratamento farmacológico , Adolescente , Adulto , Idoso , Albendazol/uso terapêutico , Criança , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
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