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1.
Huan Jing Ke Xue ; 42(11): 5169-5179, 2021 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-34708956

RESUMO

In order to better understand the industrial volatile organic compounds(VOCs) emissions in China in recent years, an industrial VOCs emission inventory was developed from 2011 to 2019, based on the dynamic emission factors method and the comprehensive source classification system. The results showed that VOCs emissions increased first from 11122.7 kt in 2011 to 13397.9 kt in 2017, and then decreased to 13247.0 kt in 2019. The emission structure of the four source categories changed. The contribution from basic organic chemical industries, gasoline storage and transportation, manufacturing(i.e., coatings, inks, pigments, and similar products), and industrial protective coatings continued to increase. On the contrary, the contributions of oil and natural gas processing, automobile, and container manufacturing industries declined over the study period. Among the industrial emissions in China in 2019, industrial coating, printing, and basic organic chemical industries emitted large amounts of VOCs(accounting for 39.2% of the total emission), and because their contribution became increasingly prominent since 2011, these sectors will be the key emission sources in the future. With respect to the spatial distribution in 2019, East China and South China had the largest VOCs emissions. Shandong, Guangdong, Jiangsu, and Zhejiang were the four provinces that contributed the most, accounting for 40.6% of the total VOCs emissions.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Gasolina , Compostos Orgânicos Voláteis/análise
2.
J Nanobiotechnology ; 18(1): 110, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32762751

RESUMO

BACKGROUNDS: Due to the unexpected side effects of the iodinated contrast agents, novel contrast agents for X-ray computed tomography (CT) imaging are urgently needed. Nanoparticles made by heavy metal elements are often employed, such as gold and bismuth. These nanoparticles have the advantages of long in vivo circulation time and tumor targeted ability. However, due to the long residence time in vivo, these nanoparticles may bring unexpected toxicity and, the preparation methods of these nanoparticles are complicated and time-consuming. METHODS: In this investigation, a small molecular bismuth chelate using diethylenetriaminepentaacetic acid (DPTA) as the chelating agent was proposed to be an ideal CT contrast agent. RESULTS: The preparation method is easy and cost-effective. Moreover, the bismuth agent show better CT imaging for kidney than iohexol in the aspect of improved CT values. Up to 500 µM, the bismuth agent show negligible toxicity to L02 cells and negligible hemolysis. And, the bismuth agent did not induce detectable morphology changes to the main organs of the mice after intravenously repeated administration at a high dose of 250 mg/kg. The pharmacokinetics of the bismuth agent follows the first-order elimination kinetics and, it has a short half-life time of 0.602 h. The rapid clearance from the body promised its excellent biocompatibility. CONCLUSIONS: This bismuth agent may serve as a potential candidate for developing novel contrast agent for CT imaging in clinical applications.


Assuntos
Bismuto , Meios de Contraste , Tomografia Computadorizada por Raios X/métodos , Animais , Bismuto/química , Bismuto/farmacocinética , Bismuto/toxicidade , Meios de Contraste/química , Meios de Contraste/farmacocinética , Meios de Contraste/toxicidade , Iohexol/química , Iohexol/farmacocinética , Rim/diagnóstico por imagem , Rim/metabolismo , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Camundongos , Ácido Pentético/química , Ácido Pentético/farmacocinética , Distribuição Tecidual , Imagem Corporal Total
3.
Nano Lett ; 20(3): 2062-2071, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32096643

RESUMO

Tumor hypoxia is the Achilles heel of oxygen-dependent photodynamic therapy (PDT), and tremendous challenges are confronted to reverse the tumor hypoxia. In this work, an oxidative phosphorylation inhibitor of atovaquone (ATO) and a photosensitizer of chlorine e6 (Ce6)-based self-delivery nanomedicine (designated as ACSN) were prepared via π-π stacking and hydrophobic interaction for O2-economized PDT against hypoxic tumors. Specifically, carrier-free ACSN exhibited an extremely high drug loading rate and avoided the excipient-induced systemic toxicity. Moreover, ACSN not only dramatically improved the solubility and stability of ATO and Ce6 but also enhanced the cellular internalization and intratumoral permeability. Abundant investigations confirmed that ACSN effectively suppressed the oxygen consumption to reverse the tumor hypoxia by inhibiting mitochondrial respiration. Benefiting from the synergistic mechanism, an enhanced PDT effect of ACSN was observed on the inhibition of tumor growth. This self-delivery system for oxygen-economized PDT might be a potential appealing clinical strategy for tumor eradication.


Assuntos
Neoplasias Mamárias Experimentais , Nanomedicina , Nanopartículas , Fotoquimioterapia , Porfirinas , Animais , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Nanopartículas/química , Nanopartículas/uso terapêutico , Porfirinas/química , Porfirinas/farmacocinética , Porfirinas/farmacologia
4.
Int J Mol Med ; 44(3): 1091-1105, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31524224

RESUMO

Damaged endothelial progenitor cells (EPCs) are associated with poor prognosis in diabetic myocardial infarction (DMI). Our previous studies revealed that an impaired Sonic hedgehog (Shh) pathway contributes to insufficient function in diabetic EPCs; however, the roles of the Shh pathway in diabetic EPC apoptosis under basal and hypoxic/ischemic conditions remain unknown. Therefore, the present study investigated whether Shh revitalized diabetic EPCs and consequently improved the deteriorative status of DMI. For this purpose, streptozotocin injection was used in male C57/BL6 mice to induce type­1 diabetes, and diabetic EPCs were isolated from the bone marrow. Apoptosis, cell function, and protein expression were investigated in EPCs in vitro. Mouse hearts were injected with adenovirus Shh­modified diabetic EPCs (DM­EPCShh) or control DM­EPCNull immediately after coronary artery ligation in vivo. Cardiac function, capillary numbers, fibrosis, and cell apoptosis were then detected. First, the in vitro results demonstrated that the apoptosis of diabetic EPCs was reduced following treatment with Shh protein for 24 h, under normal or hypoxic conditions. BMI1 proto­oncogene (Bmi1), an antiapoptotic protein found in several cells, was reduced in diabetic EPCs under normal or hypoxic conditions, but was upregulated after Shh protein stimulation. When Bmi1­siRNA was administered, the antiapoptotic effect of Shh protein was significantly reversed. In addition, p53, a Bmi1­targeted gene, was demonstrated to mediate the antiapoptotic effect of the Shh/Bmi1 pathway in diabetic EPCs. The Shh/Bmi1/p53 axis also enhanced the diabetic EPC function. In vivo, Shh­modified diabetic EPCs exhibited increased EPC retention and decreased apoptosis at 3 days post­DMI. At 14 days post­DMI, these cells presented enhanced capillary density, reduced myocardial fibrosis and improved cardiac function. In conclusion, the present results demonstrated that the Shh pathway restored diabetic EPCs through the Shh/Bmi1/p53 axis, suppressed myocardial apoptosis and improved myocardial angiogenesis, thus reducing cardiac fibrosis and finally restoring myocardial repair and cardiac function in DMI. Thus, the Shh pathway may serve as a potential target for autologous cell therapy in diabetic myocardial ischemia.


Assuntos
Células Progenitoras Endoteliais/metabolismo , Regulação da Expressão Gênica , Proteínas Hedgehog/metabolismo , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/metabolismo , Animais , Apoptose/genética , Biomarcadores , Biópsia , Células da Medula Óssea/metabolismo , Diabetes Mellitus Experimental , Ecocardiografia , Inativação Gênica , Hipóxia , Imuno-Histoquímica , Masculino , Camundongos , Modelos Biológicos , Infarto do Miocárdio/diagnóstico , RNA Interferente Pequeno/genética , Transdução de Sinais
5.
Macromol Biosci ; 19(4): e1800410, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30576082

RESUMO

In this paper, a self-delivery chimeric peptide PpIX-PEG8 -KVPRNQDWL is designed for photodynamic therapy (PDT) amplified immunotherapy against malignant melanoma. After self-assembly into nanoparticles (designated as PPMA), this self-delivery system shows high drug loading rate, good dispersion, and stability as well as an excellent capability in producing reactive oxygen species (ROS). After cellular uptake, the ROS generated under light irradiation could induce the apoptosis and/or necrosis of tumor cells, which would subsequently stimulate the anti-tumor immune response. On the other hand, the melanoma specific antigen (KVPRNQDWL) peptide could also activate the specific cytotoxic T cells for anti-tumor immunity. Compared to immunotherapy alone, the combined photodynamic immunotherapy exhibits significantly enhanced inhibition of melanoma growth. Both in vitro and in vivo investigations confirm that PDT of PPMA has a positive effect on anti-tumor immune response. This self-delivery system demonstrates a great potential of this PDT amplified immunotherapy strategy for advanced or metastatic tumor treatment.


Assuntos
Antígenos de Neoplasias/farmacologia , Sistemas de Liberação de Medicamentos , Imunoterapia , Melanoma Experimental/terapia , Peptídeos/farmacologia , Fotoquimioterapia , Animais , Antígenos de Neoplasias/imunologia , Células COS , Chlorocebus aethiops , Imunidade Celular/efeitos dos fármacos , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/patologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-28711354

RESUMO

The metabolic thermogenesis plays important roles in thermoregulation, and it may be also involved in body fat regulation. The thermogenesis of brown adipose tissue (BAT) is largely affected by ambient temperature, but it is unclear if the roles in body fat regulation are dependent on the temperature. In the present study, uncoupling protein 1 (ucp1)-based BAT thermogenesis, energy budget and body fat content were examined in the striped hamsters fed high fat diet (HF) at cold (5°C) and warm (30°C) temperatures. The effect of 2, 4-dinitrophenol (DNP), a chemical uncoupler, on body fat was also examined. The striped hamsters showed a notable increase in body fat following the HF feeding at 21°C. The increased body fat was markedly elevated at 30°C, but was significantly attenuated at 5°C compared to that at 21°C. The hamsters significantly increased energy intake at 5°C, but consumed less food at 30°C relative to those at 21°C. Metabolic thermogenesis, indicated by basal metabolic rate, UCP1 expression and/or serum triiodothyronine levels, significantly increased at 5°C, but decreased at 30°C compared to that at 21°C. A significant decrease in body fat content was observed in DNP-treated hamsters relative to the controls. These findings suggest that the roles of metabolic thermogenesis in body fat regulation largely depend on ambient temperature. The cold-induced enhancement of BAT thermogenesis may contribute the decreased body fat, resulting in a lean mass. Instead, the attenuation of BAT thermogenesis at the warm may result in notable obesity.


Assuntos
Tecido Adiposo/metabolismo , Dieta Hiperlipídica , Termogênese , Animais , Metabolismo Basal , Cricetinae , Temperatura
7.
Org Lett ; 19(5): 1196-1199, 2017 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-28207274

RESUMO

Spiroschincarins A-E (1-5), five novel spirocyclic schinortriterpenoids featuring a unique 1-oxaspiro[6.6]tridecane motif, were isolated from the fruit of Schisandra incarnata. Their structures with absolute configurations were determined by extensive spectroscopic analyses, single-crystal X-ray diffractions, and experimental ECD (electronic circular dichroism). A hypothetical biogenetic pathway of 1-5 was postulated.

8.
J Therm Biol ; 58: 72-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27157336

RESUMO

It has been suggested that the up-regulation of uncoupling proteins (UCPs) decreases reactive oxygen species (ROS) production, in which case there should be a negative relationship between UCPs expression and ROS levels. In this study, the effects of temperature and food restriction on ROS levels and metabolic rate, UCP1 mRNA expression and antioxidant levels were examined in the brown adipose tissue (BAT) of the striped hamsters (Cricetulus barabensis). The metabolic rate and food intake of hamsters which had been restricted to 80% of ad libitum food intake, and acclimated to a warm temperature (30°C), decreased significantly compared to a control group. Hydrogen peroxide (H2O2) levels were 42.9% lower in food restricted hamsters than in the control. Malonadialdehyde (MDA) levels of hamsters acclimated to 30°C that were fed ad libitum were significantly higher than those of the control group, but 60.1% lower than hamsters that had been acclimated to the same temperature but subject to food restriction. There were significantly positive correlations between H2O2 and, MDA levels, catalase activity, and total antioxidant capacity. Cytochrome c oxidase activity and UCP1 mRNA expression significantly decreased in food restricted hamsters compared to the control. These results suggest that warmer temperatures increase oxidative stress in BAT by causing the down-regulation of UCP1 expression and decreased antioxidant activity, but food restriction may attenuate the effects.


Assuntos
Aclimatação , Tecido Adiposo Marrom/fisiologia , Cricetulus/fisiologia , Jejum/fisiologia , Estresse Oxidativo , Animais , Metabolismo Basal , Catalase/metabolismo , Cricetinae , Regulação para Baixo , Ingestão de Alimentos , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Temperatura Alta , Peróxido de Hidrogênio/metabolismo , Masculino , Malondialdeído/metabolismo , RNA Mensageiro/genética , Espécies Reativas de Oxigênio/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
9.
J Exp Biol ; 219(Pt 9): 1327-36, 2016 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-26944487

RESUMO

In small mammals, marked phenotypic plasticity of digestive physiology has been shown to make it easier for them to cope with energetically stressful periods, such as lactation. It has been proposed that the capacity of the gut to digest and absorb food is not the limiting factor to sustained energy intake (SusEI) during peak lactation. In this study, plasticity in energy intake and gastrointestinal morphology was examined in striped hamsters at different stages of reproduction and when raising litters of different sizes. Mechanisms associated with digestive enzymes and neuroendocrine hormones underpinning the plasticity were also examined. Females significantly increased energy intake, digestibility, digestive tract mass and the activity of stomach pepsin and small intestine maltase, sucrase and aminopeptidase in peak lactation compared with the non-productive and post-lactating periods. Further, females raising large litters significantly increased energy intake, digestibility, gastrointestinal mass and activity of digestive enzymes, and weaned heavier offspring compared with those nursing small and medium litters, indicating that the significant plasticity of digestive physiology increased reproductive performance. Agouti-related protein (AgRP) mRNA expression in the hypothalamus was up-regulated significantly in females raising large litters relative to those raising small litters. Serum leptin levels, and mRNA expression of hypothalamus neuropeptide Y (NPY) and the anorexigenic neuropeptides pro-opiomelanocortin (POMC) and cocaine- and amphetamine-regulated transcript (CART) did not differ among females raising small, medium and large litters. Leptin levels in lactation may only reflect a state of energy balance rather than being the prime driver of hyperphagia. Some hypothalamic neuropeptides, such as NPY, POMC and CART, may be involved in the limits to the SusEI during lactation.


Assuntos
Antígenos CD13/metabolismo , Cricetulus/fisiologia , Trato Gastrointestinal/enzimologia , Pepsina A/metabolismo , Sacarase/metabolismo , alfa-Glucosidases/metabolismo , Tecido Adiposo/metabolismo , Animais , Cricetinae , Cricetulus/anatomia & histologia , Digestão , Ingestão de Energia , Feminino , Trato Gastrointestinal/fisiologia , Lactação , Leptina/sangue , Tamanho da Ninhada de Vivíparos
10.
Exp Ther Med ; 10(5): 1750-1758, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26640546

RESUMO

Our previous study demonstrated that an impaired sonic hedgehog (Shh) pathway contributed to cardiac dysfunction in type 1 diabetic mice with myocardial infarction (MI). The present study aimed to test the hypothesis that oxidative stress may contribute to the impaired Shh pathway and cardiac dysfunction in type 1 diabetic mice with MI. Streptozotocin-induced type 1 diabetic mice (C57/Bl6, male) and rat neonatal cardiomyocytes were used in the present study. Mice were randomly assigned to undergo ligation of the coronary artery or pseudosurgery. A potent antioxidant Tempol was administered in vivo and in vitro. Cardiac function was assessed by echocardiography, capillary density by immunohistochemisty, percentage of myocardial infarct using Massons trichrome staining, reactive oxygen species detection using dihydroethidium dye or 2,7-dichlorofluorescein diacetate probe and protein expression levels of the Shh pathway by western blot analysis. The antioxidant Tempol was shown to significantly increase myocardial protein expression levels of Shh and patched-1 (Ptc1) at 7-18 weeks and improved cardiac function at 18 weeks in type 1 diabetic mice, as compared with mice receiving no drug treatment. Furthermore, myocardial protein expression levels of Shh and Ptc1 were significantly upregulated on day 7 after MI, and capillary density was enhanced. In addition, the percentage area of myocardial infarct was reduced, and the cardiac dysfunction and survival rate were improved on day 21 in diabetic mice treated with Tempol. In vitro, treatment of rat neonatal cardiomyocytes with a mixture of xanthine oxidase and xanthine decreased protein expression levels of Shh and Ptc1 in a concentration-dependent manner, and Tempol attenuated this effect. These results indicate that oxidative stress may contribute to an impaired Shh pathway in type 1 diabetic mice, leading to diminished myocardial healing and cardiac dysfunction. Antioxidative strategies aimed at restoring the endogenous Shh pathway may offer a useful means for improving diabetic cardiac function.

11.
PLoS One ; 10(10): e0141604, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26505889

RESUMO

Life-history theory assumes that animals can balance the allocation of limited energy or resources to the competing demands of growth, reproduction and somatic maintenance, while consequently maximizing their fitness. However, somatic damage caused by oxidative stress in reproductive female animals is species-specific or is tissue dependent. In the present study, several markers of oxidative stress (hydrogen peroxide, H2O2 and malonadialdehyde, MDA) and antioxidant (catalase, CAT and total antioxidant capacity, T-AOC) were examined in striped hamsters during different stages of reproduction with experimentally manipulated litter size. Energy intake, resting metabolic rate (RMR), and mRNA expression of uncoupling protein 1 (UCP1) in brown adipose tissue (BAT) and UCP3 in skeletal muscle were also examined. H2O2 and MDA levels did not change in BAT and liver, although they significantly decreased in skeletal muscle in the lactating hamsters compared to the non-reproductive group. However, H2O2 levels in the brain were significantly higher in lactating hamsters than non-reproductive controls. Experimentally increasing litter size did not cause oxidative stress in BAT, liver and skeletal muscle, but significantly elevated H2O2 levels in the brain. CAT activity of liver decreased, but CAT and T-AOC activity of BAT, skeletal muscle and the brain did not change in lactating hamsters compared to non-reproductive controls. Both antioxidants did not change with the experimentally increasing litter size. RMR significantly increased, but BAT UCP1 mRNA expression decreased with the experimentally increased litter size, suggesting that it was against simple positive links between metabolic rate, UCP1 expression and free radicals levels. It may suggest that the cost of reproduction has negligible effect on oxidative stress or even attenuates oxidative stress in some active tissues in an extensive range of animal species. But the increasing reproductive effort may cause oxidative stress in the brain, indicating that oxidative stress in response to reproduction is tissue dependent. These findings provide partial support for the life-history theory.


Assuntos
Antioxidantes/metabolismo , Metabolismo Energético , Estresse Oxidativo , Reprodução/genética , Tecido Adiposo Marrom , Animais , Catalase/biossíntese , Cricetinae , Feminino , Regulação da Expressão Gênica , Peróxido de Hidrogênio/metabolismo , Lactação/metabolismo , Tamanho da Ninhada de Vivíparos , Fígado/metabolismo , Malondialdeído/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reprodução/fisiologia
12.
Chem Pharm Bull (Tokyo) ; 60(6): 785-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22689432

RESUMO

Phytochemical investigations of the root bark of Juglans cathayensis DODE. led to the isolation of three new naphthalenyl glycosides, Jugnaphthalenoside A-C (1-3). Their structures were elucidated on the basis of extensive analysis of spectroscopic data. The cytotoxicities of the three new compounds were also evaluated.


Assuntos
Antineoplásicos/química , Glicosídeos/química , Juglans/química , Casca de Planta/química , Raízes de Plantas/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular
13.
Zhongguo Zhong Yao Za Zhi ; 30(8): 584-6, 2005 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16011279

RESUMO

OBJECTIVE: To study the chemical constituents from the rhizome of Impatiens pritzellii var. hupehensis. METHOD: The rhizome were extracted with methanol, isolated and purified by column chromatography on silica gel. All the compounds were identified on the basis of spectral analysis (including IR, MS, NMR) and physico-chemical characters. RESULT: Five compounds were identified as a-spinasterol (I), alpha-spinasteryl-7, 22-dien-3-O-beta-D-glucopyranoside (II), stigmast-7, 22-dien-3-one (III), stearic acid (IV), hentriantane (V). CONCLUSION: Compound I is isolated from this plant for the first time, Compound II, III, IV, V are isolated from genus Balsaminaceae for the first time.


Assuntos
Impatiens/química , Plantas Medicinais/química , Estigmasterol/análogos & derivados , Rizoma/química , Ácidos Esteáricos/química , Ácidos Esteáricos/isolamento & purificação , Estigmasterol/química , Estigmasterol/isolamento & purificação
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