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1.
Chemosphere ; 339: 139537, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37478992

RESUMO

There have been concerns raised about the environmental effects of perfluoroalkyl substances (PFASs) because of their toxicity, widespread distribution, and persistence. Understanding the occurrences and ecological risk posed by PFASs is essential, especially for the short-chain replacements perfluorobutanoic acid (PFBA) and perfluorobutane sulfonic acid (PFBS), which are now becoming predominant PFASs. The lack of aquatic life criteria (ALC), however, prevents an accurate assessment of the ecological risks of PFBA and PFBS. This study thus investigated the occurrence of 15 PFASs at 29 sampling sites in Shaying River Basin (in China) systematically, conducted the toxicity tests of PFBA and PFBS on eight resident aquatic organisms in China, and derived the predicted non-effect concentration (PNEC) values for PFBA and PFBS for two environmental media in China. The results showed that the total PFASs concentrations (ΣPFASs) ranged from 5.07 to 20.32 ng/L (average of 10.95 ng/L) in surface water, whereas in sediment, ΣPFASs ranged from 6.46 to 20.05 ng/g (dw) (average of 11.51 ng/g). The presence of PFBS was the most prominent PFASs in both water (0.372-8.194 ng/L) and sediment (4.54-15.72 ng/g), demonstrating that short-chain substitution effects can be observed in watersheds. The PNEC values for freshwater and sediment were 6.60 mg/L and 8.30 mg/kg (ww), respectively, for PFBA, and 14.04 mg/L, 37.08 mg/kg (ww), respectively, for PFBS. Ecological risk assessment of two long-chain PFASs, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), and two short-chain PFASs, PFBA and PFBS, using the hazard quotient method revealed that Shaying River and other major River Basins in China were at risk of PFOS contamination. This study contributes to a better understanding of the presence and risk of PFASs in the Shaying River and first proposes the ALCs for PFBA and PFBS in China, which could provide important reference information for water quality standards.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Poluentes Químicos da Água , Rios , Monitoramento Ambiental , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Exposição Ambiental , Ácidos Alcanossulfônicos/toxicidade , Ácidos Alcanossulfônicos/análise , Fluorocarbonos/toxicidade , Fluorocarbonos/análise , China
2.
Ecotoxicol Environ Saf ; 215: 112141, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33740491

RESUMO

Current Chinese surface water environmental quality standard GB3838-2002 for ammonia fails to take water quality factors and native organism distributions in different basins into consideration. In this study, ammonia toxicity tests were performed using three aquatic organisms native to the Shaying River Basin (China). Published ammonia toxicity data with pH and temperature, and toxicity data acquired in this study were used to establish water quality criteria. The final criterion maximum concentration (CMC) and criterion continuous concentration (CCC) for the Shaying River Basin were 5.09 and 1.36 (mg total ammonia nitrogen (TAN))/L (pH 7 and 20 °C), respectively. In addition, based on the corresponding relationship between ammonia toxicity and temperature and pH, the ecological risk assessment of ammonia was conducted in different seasons for the Shaying River using a tiered approach of both hazard quotient (HQ) and the joint probability (JPC) methods. Two methods gave consistent results: the ecological risks of ammonia to aquatic species in the Shaying River Basin were severe and the risk could be ranked as wet season > flat season > dry season. It is therefore indicating that monitoring, evaluation, and early warning of ammonia pollution need to be taken to prevent and control the risks posed by ammonia pollution, especially for wet season (because of high temperatures and pH) or flat season (because of high pH values). We hope the present work could provide valuable information to manage and control ammonia pollution in the Shaying River Basin.


Assuntos
Amônia/análise , Poluentes Químicos da Água/análise , Amônia/toxicidade , Organismos Aquáticos , China , Monitoramento Ambiental/métodos , Nitrogênio , Medição de Risco/métodos , Rios/química , Estações do Ano , Testes de Toxicidade , Poluentes Químicos da Água/toxicidade , Qualidade da Água/normas
3.
World J Emerg Med ; 12(1): 54-60, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33505551

RESUMO

BACKGROUND: Acute respiratory distress syndrome (ARDS) causes substantial mortalities. Alveolar epithelium is one of the main sites of cell injuries in ARDS. As an important kind of microRNAs (miRNAs), microRNA-145 (miR-145) has been studied in various diseases, while its role in ARDS has not been investigated. METHODS: Lipopolysaccharide (LPS) was intratracheally instilled to establish a rat ARDS model. Cytokines from bronchoalveolar lavage fluid (BALF) were measured using rat tumor necrosis factor-α and interleukin-6 enzyme-linked immunosorbent assay kits (R&D Systems), and the pathological structures were evaluated using hematoxylin and eosin (H&E) staining and transmission electron microscope; the lung miR-145 messenger RNA (mRNA) was detected using quantitative polymerase chain reaction. Bioinformatics focused on the target genes and possible pathways of gene regulation. RESULTS: A rat model of LPS-induced ARDS was successfully established. The miR-145 was down-regulated in the LPS-induced ARDS lung, and mitochondrial dysfunction was observed in alveolar epithelial cells, most obviously at 72 hours after LPS. TargetScan and miRDB databases were used to predict the target genes of miR-145. A total of 428 overlapping genes were identified, seven genes were associated with mitochondrial function, and Ogt, Camk2d, Slc8a3, and Slc25a25 were verified. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were enriched in the mitogen-activated protein kinase (MAPK) signaling pathway, and Gene Ontology (GO) biological process was mainly enriched in signal transduction and transcription regulation. CONCLUSIONS: The miR-145 is down-regulated in LPS-induced ARDS, and affects its downstream genes targeting mitochondrial functions.

4.
Huan Jing Ke Xue ; 41(11): 4989-4998, 2020 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124242

RESUMO

In order to study the pollution source and ecological risk assessment of polycyclic aromatic hydrocarbons (PAHs) in the Jiaxing river network, PAHs were analyzed by GC-MS. The results show that with the influence of rainfall and surface runoff in the wet season, the types and mass concentrations of PAHs in the river network of Jiaxing differ from the dry season. Ten and 16 priority PAHs were detected in the dry season and wet season, respectively. The average mass concentration of PAHs in the dry season was 143.83ng·L-1 and 73.47ng·L-1 in the wet season. The range of mass concentration of PAHs in the dry and wet season was 77.32-283.76ng·L-1 and 13.05-133.02ng·L-1, respectively, and 2-ring and 3-ring PAHs accounted for 79.18% in the dry season and 73.60% in the wet season. PAHs pollution in the river network of Jiaxing was at a low level compared with the domestic and foreign areas. The isomer ratio and principal component analysis found that the PAHs in the Jiaxing river network mainly come from urban non-point source pollution, combustion source, and traffic pollution in the dry season and wet season. The results of the Kalf risk entropy method show that in the dry season, naphthalene(Nap), acenaphthylene(Acy), acenaphthene(Ace), fluorene(Flu), phenanthrene(Phe), anthracene(Ant), fluoranthene(Fla), pyrene(Pyr), and benzo(a)anthracene(BaA) are at moderate ecological risk. In the wet season, Nap, Acy, Flu, Phe, Fla, Pyr, BaA, benzo(b)fluoranthene(BbF), benzo(k)fluoranthene(BkF), benzo(a)pyrene(BaP), indeno(1,2,3-cd)pyrene(InP), and benzo(g,h,i)perylene(BghiP) are at moderate ecological risk. In the dry season, ∑PAHs are at moderate ecological risk, and low in the wet season. On the whole, PAHs pollution in the Jiaxing river network presents moderate ecological risk levels, and measures to reduce the ecological risk of PAHs in the river network should be taken by the Departments concerned.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Monitoramento Ambiental , Poluição Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Rios , Estações do Ano
5.
J Integr Med ; 18(3): 196-202, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32067923

RESUMO

Hepatocellular carcinoma (HCC) is a prevalent and highly malignant cancer throughout the world. Effective treatment of this disease is impeded by the high rate of metastasis, recurrence, and chemoresistance. Recent studies have revealed the close relationship between the malignant phenotype of HCC and cancer stem cells (CSCs). Therefore, CSC-targeted therapy is considered a promising strategy to eradicate HCC. Traditional Chinese medicine (TCM) can be effective in preventing recurrence and metastasis of some advanced HCC. A growing amount of literature has discovered that extracts or compounds derived from TCM exert an anti-CSC effect. This review introduces some formulas and chemical compounds derived from TCMs that have been reported to inhibit CSCs of HCC; these TCM-related drugs may help to provide an alternative approach to help manage cancers, especially for HCC which has a great potential of metastasis, recurrence, and chemoresistance.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Medicina Tradicional Chinesa , Células-Tronco Neoplásicas , Carcinoma Hepatocelular/terapia , Humanos , Neoplasias Hepáticas/terapia
6.
World J Clin Cases ; 7(21): 3649-3654, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31750349

RESUMO

BACKGROUND: We report a case of giant gastroduodenal trichobezoar, an extremely rare upper gastrointestinal bezoar due to trichotillomania and trichophagia. CASE SUMMARY: The patient was a 10-year-old girl who presented with an abdominal mass that was discovered at palpation and noninvasive imaging examinations. Computed tomography (CT) showed a well-circumscribed heterogeneous mass extending from the stomach into the duodenum. The patient underwent a laparotomy to pull out the trichobezoar. Although these imaging findings are nonspecific, trichobezoar should be included in the differential diagnosis of gastric mass, especially with the history of an irresistible urge to pull out and swallow their hair. CONCLUSION: Laparotomy is useful and practical for the management of giant gastroduodenal trichobezoar.

7.
Environ Sci Pollut Res Int ; 26(33): 34622-34632, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31654308

RESUMO

Organophosphorus pesticides are effective, cheap, and used extensively but can harm aquatic organism and human health. Here, water quality criteria (WQCs) for dichlorvos (DDVP) and malathion (MAL) were derived. Nine aquatic organisms native to China were used in toxicity tests. Published toxicity data for aquatic organisms native and non-native to China were also analyzed. DDVP and MAL WQCs were derived using (log-normal model) species sensitivity distributions. Species sensitivity distribution curves indicated native and non-native species have different sensitivities to DDVP. The sensitivities of native and non-native species to MAL were not different because non-native species data for fewer than eight genera were available, so further research is required. The results indicated that native species need to be considered when deriving WQCs. The criteria maximum concentration (CMC) and criteria continuous concentration (CCC) were 1.33 and 0.132 µg/L, respectively, for DDVP, and 0.100 and 0.008 µg/L, respectively, for MAL. The CMCs for DDVP and MAL derived using ETX 2.0 software and species sensitivity ranks were different from the CMCs obtained using the SSD method because of parameter uncertainties. The DDVP and MAL WQCs were significantly lower than Chinese surface water quality standard thresholds. The results provide basic data for revising these thresholds.


Assuntos
Diclorvós/análise , Malation/análise , Praguicidas/análise , Poluentes Químicos da Água/análise , Qualidade da Água/normas , Animais , Organismos Aquáticos , China , Humanos , Testes de Toxicidade
8.
J Control Release ; 131(1): 77-82, 2008 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-18692530

RESUMO

Hepatocyte growth factor (HGF) was encapsulated into sterically stabilized liposomes (SSL) in order to protect it from in vivo degradation. Cyclic Arg-Gly-Asp (RGD) peptides were combined with maleimide-[poly (ethylene glycol)]-1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (MAL-PEG-DOPE) incorporated into SSL. The average percentage of HGF encapsulated into liposomes was 32.38%, the size of liposomes was 91.56 nm and the polydispersity index was 0.164. In vivo, histological observation of the rat livers revealed that injection of RGD-SSL-HGF induced more significant remission of liver cirrhosis than injection of SSL-HGF, HGF alone, HGF plus RGD-SSL and saline. When the histological score, the collagen surface density, the hydroxyproline content and the expression of procollagen alpha1 (I) and alpha1 (III) mRNA in the liver were evaluated, all values were smallest in the RGD-SSL-HGF group. In contrast, an increase in apoptotic alpha-SMA-positive cells was noted in the RGD-SSL-HGF group. Together, this data suggests that targeted liposomes encapsulating HGF is a promising therapeutic modality in terms of promoting the remission of liver cirrhosis by promoting collagen fiber digestion, inhibiting collagen production, and promoting apoptosis of alpha-SMA-positive cells in rats with cirrhosis.


Assuntos
Fator de Crescimento de Hepatócito/uso terapêutico , Lipossomos/uso terapêutico , Cirrose Hepática Experimental/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Colágeno Tipo I/análise , Cadeia alfa 1 do Colágeno Tipo I , Portadores de Fármacos/síntese química , Portadores de Fármacos/uso terapêutico , Fator de Crescimento de Hepatócito/administração & dosagem , Fator de Crescimento de Hepatócito/metabolismo , Hidroxiprolina/análise , Lipossomos/síntese química , Lipossomos/química , Fígado/química , Fígado/efeitos dos fármacos , Maleimidas/síntese química , Oligopeptídeos/síntese química , Oligopeptídeos/química , Fosfatidiletanolaminas/síntese química , Fosfatidiletanolaminas/química , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Ratos
9.
J Pharmacol Exp Ther ; 322(2): 560-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17510318

RESUMO

Targeting hepatic stellate cells (HSCs) has been challenging due to the lack of specific receptors or motifs on the cells. The aim of the present study was to develop a HSC-specific system for improving drug delivery to HSCs. The affinity of a cyclic peptide containing Arg-Gly-Asp (cRGD) to collagen type VI receptor on HSCs was examined in both in vitro and in vivo experiments. Sterically stable liposomes (SSLs) were modified with this peptide to yield a new carrier, cRGD-SSL. The targeting efficiency of this carrier in delivering interferon (IFN)-alpha1b was investigated in a rat model of liver fibrosis induced by bile duct ligation (BDL). When incubating HSCs or hepatocytes with cyclic RGD peptide, the peptide was bound preferentially to activated HSCs. Biodistribution study showed that the accumulation of cRGD peptide-labeled liposomes in HSCs isolated from BDL rats was 10-fold more than unlabeled SSLs. BDL rats receiving injections of IFN-alpha1b entrapped in cRGD-SSL exhibited significantly reduced extent of liver fibrosis compared with BDL control rats or BDL rats treated with IFN-alpha1b entrapped in SSLs. Thus, cRGD-SSL is an efficient drug carrier, which selectively targets activated HSCs and improves drug therapy for liver fibrosis to a significant extent. This liposomal formulation represents a new means of targeting drug carrier for the treatment of liver fibrosis, and it may have potential clinical applications.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Interferon-alfa/administração & dosagem , Cirrose Hepática/tratamento farmacológico , Pericitos/metabolismo , Alanina Transaminase/sangue , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Colestase Extra-Hepática/complicações , Colestase Extra-Hepática/tratamento farmacológico , Colestase Extra-Hepática/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo III/genética , Endocitose/fisiologia , Expressão Gênica/efeitos dos fármacos , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hidroxiprolina/metabolismo , Interferon-alfa/química , Interferon-alfa/farmacologia , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Cirrose Hepática/etiologia , Cirrose Hepática/metabolismo , Masculino , Maleimidas/química , Oligopeptídeos/química , Peptídeos Cíclicos/química , Peptídeos Cíclicos/metabolismo , Pericitos/efeitos dos fármacos , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Ratos , Ratos Wistar , Lipossomas Unilamelares/química
10.
Zhonghua Yi Xue Za Zhi ; 85(15): 1015-20, 2005 Apr 20.
Artigo em Chinês | MEDLINE | ID: mdl-16029541

RESUMO

OBJECTIVE: To evaluate the antifibrotic effect of receptor-mediated sterical stability liposome (SSL) targeting hepatic stellate cells (HSCs) and containing recombinant human interferon-alpha 1b (IFNalpha-1b) on hepatic cirrhosis. METHODS: The ligand, cyclo (RGD) with specific affinity to HSCs, was incorporated via PEG into the lipid bilayers of SSL. Forty male SD rats were randomly divided into 4 equal groups: liver fibrosis model group undergoing double ligation and cutting of the common bile duct (BDL group), BDL + IFN-SSL group, undergoing BDL and injection of IFN 50,000 IU per week via caudal vein for 4 times; IFN-RGD-SSL treatment group, undergoing BDL and injection of IFN-RGD-SSL (equal to 50,000 IU per week) via caudal vein for 4 times; and sham operation group used as control. The rats were killed 24 hours after the last injection. Their livers and serum samples were collected. Pathological changes of the liver were observed with HE and alpha-SMA immunohistochemical staining. Biochemical automatic analyzer was used to test the serum indices of liver function: ALT, AST, total bilirubin (TBIL), alkaline phosphatase, and gamma-glutamine (gamma-GT). Radioimmunoassay method was used to examine the s serum index of liver fibrosis: HA, procollagen III (PCIII), LN, and CIV. Colorimetry was used to examine the level of hydroxyl proline (Hyp). RT-PCR was used to detect the mRNA expression of type I collagen. Western blotting was used to examine the protein expression of alpha-SMA of HSC. RESULTS: Compared with the control group, liver fibrosis was seen in the other 3 groups, especially in the BDL group. In comparison with the sham operation group, the levels of serum indices of liver fibrosis, liver hydroxyl proline content, and expression of type I collagen mRNA and alpha-SMA protein in liver were significantly higher in the other groups (all P < 0.05), being significantly lower in the BDL + IFN-RGD-SSL group than in the BDL + IFN-SSL group (all P < 0.05). CONCLUSION: The receptor-mediated IFN-RGD-SSL displays good targeting antifibrotic effects on liver fibrosis.


Assuntos
Interferon Tipo I/uso terapêutico , Cirrose Hepática Experimental/terapia , Oligopeptídeos/uso terapêutico , Peptídeos Cíclicos/uso terapêutico , Actinas/biossíntese , Actinas/genética , Animais , Colágeno Tipo I/biossíntese , Colágeno Tipo I/genética , Lipossomos , Testes de Função Hepática , Masculino , RNA Mensageiro/biossíntese , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes
11.
Zhonghua Gan Zang Bing Za Zhi ; 13(5): 362-5, 2005 May.
Artigo em Chinês | MEDLINE | ID: mdl-15918972

RESUMO

OBJECTIVE: To investigate the binding characteristics between an artificial Arg-Gly-Asp (RGD)-containing cyclic peptide [cyclo(CGRGDSPK)] and rat hepatic stellate cells (HSC). METHODS: An artificial RGD-containing cyclic peptide was labeled with fluorescein isothiocyanate (FITC). HSCs were isolated by collagenase in situ liver recirculating and purified by density gradient centrifugation from normal rats. The cells were cultured for 5 days of primary culture (quiescent phenotype) or for 7 days of secondary culture (activated phenotype). To access the binding and uptake, HSCs were incubated with FITC-cRGD of different concentrations at 4 degree C or 37 degree C, and then the binding and uptake were investigated by flow cytometry. The location of FITC-cRGD in HSC was investigated by fluorescent microscopy. Kd and maximal binding sites per cell were calculated by radioligand binding assay (RBA) of receptors using 3H-cRGD. In the interim, FITC-cAGA was used as a peptide control devoid of any binding site. RESULTS: The binding between FITC-cRGD and HSC was saturable, time- and dose-dependent and could compete with overdosed unlabeled cRGD. The fluorescence was mainly distributed in cytoplasma, especially near the nuclei. Kd was 7.05 x 10(-9) mol/L and Bmax per cell was nearly 6.79 x 10(5). CONCLUSIONS: The results demonstrate that cRGD are specifically taken up by HSC through a receptor-mediated pathway. The information is useful for understanding the ligand-receptor interaction of HSC. FITC labeled cyclic RGD-peptides meet the standards of special ligands and FITC does not change the binding activation of cyclic RGD-peptides.


Assuntos
Hepatócitos/citologia , Oligopeptídeos/farmacologia , Peptídeos Cíclicos/farmacologia , Animais , Sítios de Ligação , Células Cultivadas , Hepatócitos/metabolismo , Ligação Proteica , Ratos
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