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1.
Exp Cell Res ; : 111897, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32035951

RESUMO

Mucins are major macromolecular components of lung mucus that are mainly responsible for the viscoelastic property of mucus. MUC5AC is a major mucin glycoprotein that is hypersecreted in asthmatic individuals. Vascular endothelial growth factor (VEGF) has been implicated in inflammatory and airway blood vessel remodeling in asthmatics. Our previous studies indicate that VEGF upregulates MUC5AC expression by interacting with VEGF receptor 2 (VEGFR2). It has been shown that dexamethasone (Dex) downregulates MUC5AC expression; however, the underlying mechanisms have not been completely elucidated. Therefore, we sought to investigate the effect of Dex on MUC5AC expression induced by VEGF and study the underlying mechanisms. We tested the effects of Dex on VEGFR2 and RhoA activation, caveolin-1 expression, and the association of caveolin-1 and VEGFR2 in primary bronchial epithelial cells. Dex downregulated MUC5AC mRNA and protein levels in a dose- and time-dependent manner, and suppressed the activation of VEGFR2 and RhoA induced by VEGF. Additionally, Dex upregulated caveolin-1 protein levels in a dose- and time-dependent manner. Furthermore, phospho-VEGFR2 expression was decreased through overexpression of caveolin-1 and increased after caveolin-1 knockdown. Dex treatment attenuated the VEGF-decreased association of caveolin-1 and VEGFR2. Collectively, our findings suggest that Dex downregulates VEGF-induced MUC5AC expression by inactivating VEGFR2 and RhoA. Furthermore, decreased MUC5AC expression by Dex was related to the increased association of caveolin-1 with VEGFR2. Further studies characterizing these mechanisms are required to facilitate the development of improved treatment strategies for asthma.

2.
J Affect Disord ; 266: 465-472, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-32056914

RESUMO

BACKGROUND: Lipid profile disturbances are frequently observed in major depressive disorder (MDD) and constitute to high mortality rates. However, less is known about whether this risk is present in patients with first-episode MDD. Therefore, this meta-analysis was conducted to examine if lipid parameters differed between healthy controls and first-episode MDD patients. METHODS: Cochrane Library, PubMed, PsycINFO, EMBASE, Chinese Journal Net, and WanFang databases were searched from inception to October 23, 2018. The primary outcomes were triglycerides, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and total cholesterol levels. RESULTS: A total of 11 case-control studies compared 690 subjects with first-episode MDD and 614 healthy controls were included and analyzed. Compared to healthy controls, patients with first-episode MDD were significantly associated with higher triglyceride (SMD = 0.29, 95% CI: 0.09, 0.48, P = 0.004) and lower HDL cholesterol levels (SMD = -0.54, 95% CI: -0.86, -0.22, P = 0.001). Subgroup analyses revealed that first-episode MDD patients with higher triglyceride and lower HDL levels were found only in Chinese and plasma group when compared to healthy controls (P < 0.05). Meta-regression analysis showed that the significant heterogeneity for triglyceride and HDL cholesterol was partly explained by the quality of study. No significant difference was found in LDL cholesterol and total cholesterol levels between the two groups. LIMITATIONS: Heterogeneity was relatively high among the included studies. CONCLUSIONS: Elevated triglyceride and decreased HDL cholesterol levels may be associated with first-episode MDD. Findings support early lipid monitoring and interventions targeting healthy lifestyle.

3.
Diabetes Res Clin Pract ; : 108068, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32044349

RESUMO

AIM: The relationship between serum Metrnl levels and visceral fat obesity (VFO) remains unclear. This study aimed to investigate the association between serum Metrnl levels and VFO in Chinese patients with type 2 diabetes. METHODS: A total of 321 Chinese patients with type 2 diabetes (226 men and 95 postmenopausal women aged 61.4±6.5 years, BMI 25.1±3.2kg/m2) were evaluated. Serum Metrnl levels were measured by enzyme linked-immunosorbent assay. Visceral fat area (VFA) was quantified via Dual Energy X-ray Absorptiometry (DXA). Correlation analyses were carried out for serum Metrnl levels and VFO. RESULTS: VFO groups(VFA ≧100cm2) have lower serum Metrnl levels than non-VFO groups(VFA <100cm2)(578.9±225.1 vs. 684.9±263.8, P = 0.001). An increasing trend in serum Metrnl levels was found to accompany the decrease in VFA. Serum Metrnl levels were negatively correlated with VFA, total cholesterol(TC), triglyceride(TG), low-density lipoprotein cholesterol(LDL-C) and albumin(ALB), but positively correlated with age, height, blood urea nitrogen(BUN), creatinine(Cr) and uric acid(UA) (all P < 0.05). Binary logistic regression analysis showed that serum Metrnl was inversely associated with VFO even after adjusted age, gender, height, TC, TG, LDL-C, ALB, BUN, Cr, and UA (odds ration[OR], 0.846; confidence interval [CI], 0.745-0.961; P = 0.010). The optimal cut-off value of serum Metrnl levels that predicted VFO was 671.3ng/ml (95%CI = 0.55 - 0.70, P = 0.001). CONCLUSIONS: Serum Metrnl levels were inversely correlated with VFO and may be a useful indicator of VFO in Chinese patients with type 2 diabetes.

4.
Environ Pollut ; 260: 114063, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-32014750

RESUMO

17ß-estradiol (E2) often coexists with tetracyclines (TCs) in wastewater lagoons at intensive breeding farms, threatening the quality of surrounding water bodies. Microbial degradation is vital in E2 removal, but it is unclear how TCs affect E2 biodegradation. This primary study investigated the mechanisms of E2 degradation by Novosphingobium sp. ES2-1 in the presence of TCs and assessed the removal efficiency of E2 by strain ES2-1 in natural waters containing TCs. E2 biodegradation was unaffected at TCs concentrations below 0.1 mg L-1 yet significantly inhibited at TCs above 10 mg L-1. As elevation of TCs, E2 biodegradation rate constant decreased, and the biodegradation kinetics equation gradually deviated from the pseudo-first-order dynamics model. Importantly, the presence of TCs, especially at high-level concentrations, significantly hindered E2 ring-opening process but promoted the condensation of some phenolic ring-opening products with NH3, thereby increasing the abundance of pyridine derivatives, which were difficult to decompose over time. Additionally, strain ES2-1 could remove 52.1-100% of nature estrogens in TCs-contaminated natural waters within 7 d. Results revealed the mechanisms of TCs in E2 biodegradation and the performance of a functional strain in estrogen removal in realistic TCs-contaminated aqueous solution.

5.
iScience ; 23(2): 100858, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-32058969

RESUMO

Chronic exposure of pancreatic ß-cells to excess glucose can lead to metabolic acceleration and loss of stimulus-secretion coupling. Here, we examined how exposure to excess glucose (defined here as concentrations above 5 mM) affects mTORC1 signaling and the metabolism of ß-cells. Acute exposure to excess glucose stimulated glycolysis-dependent mTORC1 signaling, without changes in the PI3K or AMPK pathways. Prolonged exposure to excess glucose led to hyperactivation of mTORC1 and metabolic acceleration, characterized by higher basal respiration and maximal respiratory capacity, increased energy demand, and enhanced flux through mitochondrial pyruvate metabolism. Inhibition of pyruvate transport to the mitochondria decelerated the metabolism of ß-cells chronically exposed to excess glucose and re-established glucose-dependent mTORC1 signaling, disrupting a positive feedback loop for mTORC1 hyperactivation. mTOR inhibition had positive and negative impacts on various metabolic pathways and insulin secretion, demonstrating a role for mTOR signaling in the long-term metabolic adaptation of ß-cells to excess glucose.

6.
Sci Rep ; 10(1): 2040, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029775

RESUMO

Gushen Jiedu capsule (GSJD) is a formula that has been widely used in traditional Chinese medicine for the prevention and treatment of diabetic nephropathy (DN). However, the mechanism underlying the protective effects of GSJD on DN is still unclear. This study was performed to clarify the therapeutic effects of GSJD on DN and its underlying mechanisms. High-fat diet- and streptozotocin-induced DN rats were treated with or without GSJD suspension by gavage for 8 weeks, and biochemical changes in blood and urine were analysed. Kidneys were isolated for histological, TUNEL and Western blot analysis. Compared to the DN group, the GSJD-treated groups exhibited decreased urinary albumin, ameliorated renal dysfunction, including serum creatinine and blood urea nitrogen, and attenuated total cholesterol, triglyceride and total protein levels. However, there were no significant effects of GSJD on body weight, fasting blood glucose or albuminuria. Histology showed that GSJD could retard the progression of DN and decrease the apoptosis rate from 52% to less than 20%. Western blot analysis showed that GSJD could regulate the mitochondrial apoptotic pathway by downregulating the expression of Bax and upregulating the expression of BCL-2 in the kidneys of DN rats. Moreover, the Akt pathway, an upstream signalling pathway of the BCL-2 family, was also ameliorated by GSJD. Further, the podocyte foot process markers podocin and nephrin were upregulated by GSJD in DN rats. This study demonstrated that GSJD might play a renoprotective role by inhibiting apoptosis and regulating the mitochondrial apoptotic and Akt pathways during pathological changes in DN.

7.
J Hazard Mater ; 388: 122078, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31962212

RESUMO

A multifunctional magnetic composite (0.3Ma-MgMnLDO-a) with the function of Cd2+ adsorption and paracetamol (PAM) degradation was successfully fabricated. Surface morphology showed that Fe3O4 agglomeration was overcome on composite. The composite had high specific surface area of 105.32 m2 g-1 and saturation magnetization of 40 emu∙g-1. 0.3Ma-MgMnLDO-a could reach Cd2+ adsorption equilibrium within 5 min with 99 % removal rate. The maximum adsorption capacity was 3.76 mmol·g-1 (422.62 mg g-1), which apparently higher than that of Fe3O4-a and MgMnLDO-a, indicating that the Fe/Mn synergism results in excellent ability for Cd2+ adsorption. Moreover, the composite could efficiently activate peroxymonosulfate (PMS) to rapid degrade PAM with the highest first-order rate constants (kobs = 0.116 min-1) and total organic carbon (TOC) removal rate (67.7 %), which also due to the contribution of Fe/Mn synergism in PMS activation. The cycling of MnIII/MnIV and FeII/FeIII played an important role in activating PMS to generateO2-•, 1O2 and OH for degradation. The composite exhibited both stable adsorption and catalytic performance on wide pH (3-9) and five reuse cycles. Notably, there was mutual promotion between Cd2+ and PAM adsorption, while the coexistence of Cd2+ had slight inhibition on PAM degradation. Overall, the magnetic composite had promising application for purifying heavy metals and pharmaceuticals.

8.
J Clin Lab Anal ; : e23199, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31997475

RESUMO

BACKGROUND: Our objective was to evaluate the prevalence and different diagnostic methods of breastmilk (BM)-acquired cytomegalovirus (CMV) infection in a pathologically jaundiced cohort. METHODS: A total of 400 infants confirmed with pathological jaundice at The People's Hospital of Qingyang City were screened for BM-acquired CMV infection between February 2018 and February 2019. A total of 300 infants were finally enrolled in our study. CMV infection was confirmed by detecting both CMV-DNA in various samples using FQ-PCR and CMV-IgM with chemiluminescence. Clinical and other laboratory data were collected from these infants during their hospitalization or regular visits. RESULTS: Ninety-eight (32.67%) subjects were confirmed to be BM CMV-DNA-positive, and 18 (18.37%) were diagnosed with a BM-acquired CMV infection. All 18 (100%) infants with a BM-acquired CMV infection were CMV-DNA-positive in urine, while 5 (27.78%) cases and 11 (61.11%) cases were confirmed in plasma and peripheral blood mononuclear cells (PBMCs), respectively. Only 6 (33.33%) infants were CMV-IgM-positive. Birthweight, direct bilirubin, aspartate aminotransferase, and the viral load in BM of the BM-acquired CMV group were higher than those in the non-infected group (P < .05). Low birthweight and viral load in BM were risk factors for BM-acquired CMV infection. Detecting CMV-DNA in urine samples exhibited better performance than the other methods for screening BM-acquired CMV infections. CONCLUSIONS: Our study found a high prevalence of BM-acquired CMV infection in jaundiced infants, and detecting CMV-DNA in a urine sample was the most sensitive method for disease screening.

9.
Medicine (Baltimore) ; 99(2): e18714, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914082

RESUMO

To investigate the situation of antibiotic consumption and to assess the inappropriate use on pediatric inpatients of different types hospitals in Sichuan, China.A cross-sectional survey of antibiotic prescriptions among hospitalized children aged 1month -14years were conducted from April 2018 to June 2018 in southwestern China. Antibiotic prescriptions were extracted from electronic records during hospitalization of each inpatient in five different types hospitals.In this study, the antibiotic prescription rate of hospitalized children was 66.9% (1176/1758). Compared with tertiary children hospital (TC) (46.1%), general hospitals and non-tertiary children hospitals has higher rate of antibiotic prescription (almost 85%) (P < .001). 93.4% of inpatients received parenteral antibiotic. Overall, the most common antibiotics were Cefoperazone and enzyme inhibitor, Cefixime and Azithromycin. Lower respiratory tract infection (LRTI) was the leading reason for antibiotic consumption in pediatric wards (56.8%), followed by upper respiratory tract infection (URTI) (22.2%). For children with LRTI, Cephalosporins were heavy prescribed, especially broad-spectrum third-generation Cephalosporins (60.3%). The antibiotic prescription proportion of URTI in general hospitals and non-tertiary children hospitals (more than 18%) was higher than TC (8.1%) (P < .001).There was inappropriate use of antibiotic in hospitalized children including overuse of parenteral administration, overprescribing of antibiotic on URTI and misuse of third-generation Cephalosporins in pediatric inpatients with LRTI. Compared with tertiary freestanding children hospital, the irrational antibiotic prescription of general hospitals and non-tertiary children hospitals were more serious. Management strategy should be implementer on quality improvement of antibiotic use.


Assuntos
Antibacterianos/uso terapêutico , Uso de Medicamentos/estatística & dados numéricos , Hospitais/estatística & dados numéricos , Prescrição Inadequada/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Adolescente , Antibacterianos/administração & dosagem , Criança , Criança Hospitalizada , Pré-Escolar , China , Estudos Transversais , Feminino , Hospitais Pediátricos/estatística & dados numéricos , Humanos , Lactente , Masculino , Infecções Respiratórias/tratamento farmacológico
10.
J Comp Eff Res ; 9(2): 93-102, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31958984

RESUMO

Aim: To assess the cost-effectiveness of crizotinib verses platinum-based doublet chemotherapy as the first-line treatment for anaplastic lymphoma kinase (ALK)-positive non-small-cell lung cancer (NSCLC) in the real-world setting. Methods: Data from 163 advanced ALK positive NSCLC patients were collected from West China Hospital, Sichuan University (Chengdu, China). They were categorized into two groups as treated with crizotinib (n = 83) or chemotherapy (n = 80) as a first-line therapy. The progression-free survival (PFS) as the primary clinical outcome, and the direct medical costs were collected from hospital information systems. Incremental cost-effectiveness ratio (ICER) was calculated with costs, quality-adjusted life-years, as well as the costs discounted at 3% annually. Additionally, two different kinds of medical insurance (MI) for pharma-economic assessment were considered. Results: Crizotinib improved PFS versus chemotherapy in ALK positive patients (median PFS 19.67 m vs 5.47 m; p < 0.001). Moreover, crizotinib obtained an ICER of US$36,285.39 before the end of 2016, when crizotinib, pemetrexed and anti-angiogenesis drugs were not MI covered. This is more than the willingness to pay threshold (three-times of gross domestic product per capita in mainland China or Sichuan Province). However, ICER was US$7321.16, which is less than willingness to pay, when crizotinib and all chemotherapy drugs were covered by MI from the end of 2016. Sensitivity analysis demonstrated a 99.7% probability for crizotinib to be more cost-effective than chemotherapy, when crizotinib and all anticancer drugs were MI covered. One-way sensitivity analysis for the reimbursement ratio of crizotinib indicated that cost-effective tendency for crizotinib increased as reimbursement ratio increased. Conclusion: Crizotinib could be an effective, and cost-effective first-line treatment for ALK positive advanced NSCLC with the MI coverage currently available in Chengdu, Sichuan Province, China.

11.
Phytochemistry ; 171: 112237, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31901475

RESUMO

Four undescribed alkaloids, namely collacyclumines A-D, along with a known analogue, agrocybenine, were isolated from the endophytic fungus Colletotrichum salsolae SCSIO 41021 derived from the mangrove plant Kandelia candel (L.) Druce. Collacyclumine A represents the first case of dimeric pyrrolidine alkaloid in nature. The structures of these compounds were elucidated by a combination of NMR spectra, HRESIMS data, and X-ray diffraction experiment. A proposed biosynthetic pathway of these isolated compounds were also discussed. None of compounds showed cytotoxic effects against ten cell lines.

12.
Sci Rep ; 10(1): 435, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949256

RESUMO

The aphid Schlechtendalia chinensis(Bell) induces horned galls on their primary host Rhus chinensis(Mill). These galls serve as closed habitats to support thousands of aphids per gall. Ecological parameters inside a gall are unknown. In this study, we showed that the microclimate inside galls was reltively stable, with nearly 100% humidity and 30-50 lux light regardless of outside environmental conditions. Gall-residing aphids produce waste gas and honeydew. A gall contained 26 organic volatiles inside with acetic acid as the largest component. Honeydew is rich in sugars and may provide nutrients for microbial growth. However, no evidence for pathogenic microorganisms was found inside a gall. The acidic environment in a gall may curb microbial growth. On the secondary host, the moss Plagiomnium maximoviczii (Lindb.) T. J. Kop., the microclimate is unstable and humidity fluctuated at 45~100%, while light ranged from 150 to 500 lux on different environmental conditions. Aphid alternated in two different habitats, the gall generation increased from a single fundatrix to thousands of aphids, however, survival rate of the moss generation is less 3%. A comparison of the environmental traits between gall and moss revealed that a stable habitat with dark and moist is advantageous for aphid reproduction.

13.
Cancer Lett ; 473: 130-138, 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-31904486

RESUMO

All-trans retinoic acid (ATRA) is known to be a potent inhibitor of FLT3-ITD acute myeloid leukemia (AML) cells, although the exact mechanism remains unclear. In this work, we report that ATRA causes fatal mitotic catastrophe in FLT3-ITD AML cells by degrading Chk1 kinase, and therefore preventing DNA damage repair. In order to explore a further enhancement in the inhibitory effect of ATRA on FLT3-ITD AML cells, we investigated the suitability of a combination of ATRA and DNA damage drug SN38. In vitro experiments showed that this combinatorial approach effectively inhibited the proliferation of FLT3-ITD cells and induced cell apoptosis in AML. In vivo experiments confirmed that the combination could substantially improve the anti-tumor effect of SN38. Taken together, our results indicate that ATRA down-regulates Chk1 in FLT3-ITD AML cells, and the combination of ATRA and SN38 significantly improves the anti-tumor effect of either ATRA or SN38 when used alone.

14.
Cell Mol Immunol ; 17(1): 108-109, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31772283

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

15.
Sci Total Environ ; 703: 135547, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31761365

RESUMO

As an element with well-known toxicity, excessive thallium (Tl) in farmland soils, may threaten food security and induce extreme risks to human health. Identification of key contamination sources is prerequisite for remediation technologies. This study aims to examine the contamination level, health risks and source apportionment of Tl in common vegetables from typical farmlands distributed over a densely populated residential area in a pyrite mine city, which has been exploiting Tl-bearing pyrite minerals over 50 years. Results showed excessive Tl levels were exhibited in most of the vegetables (0.16-20.33 mg/kg) and alarming health risks may induce from the vegetables via the food chain. Source apportionment of Tl contamination in vegetables was then evaluated by using Pb isotope fingerprinting technique. Both vegetables and soils were characterized with overall low 206Pb/207Pb. This indicated that a significant contribution may be ascribed to the anthropogenic activities involving pyrite deposit exploitation, whose raw material and salgs were featured with lower 206Pb/207Pb. Further calculation by binary mixing model suggested that pyrite mining and smelting activities contributed 54-88% to the thallium contamination in vegetables. The results highlighted that Pb isotope tracing is a suitable technique for source apportionment of Tl contamination in vegetables and prime contamination from pyrite mining/smelting activities urges authorities to initiate proper practices of remediation.

16.
Chemosphere ; 243: 125343, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31751929

RESUMO

Due to the huge consumption of caffeinated food, beverages and medicines around the world, caffeine has been considered as a most representative pharmaceutically active compound (PhAC) pollutant based on its high abundance in environment and its indicator property for anthropogenic inputs of PhACs to water bodies. This review analyzed the existing literature about the bioaccumulation and environmental risks of caffeine residues in non-target organisms. There are 6 studies which were published in the last 5 years have reported the distribution of caffeine in tissues of aquatic organisms including fishes, clams, macroalgae and other aquatic plants, suggesting bioaccumulation of caffeine in organisms. The maximum detected levels of caffeine residues in tissues ranged from 1.55 to 344.9 ng/g. Importantly, definitive evidences have been provided that environmentally relevant caffeine concentrations exert adverse impacts on aquatic species and terrestrial insects, which included lethality, decreasing general stress, inducing oxidative stress and lipid peroxidation, affecting energy reserves and metabolic activity, neurotoxic effects, affecting reproduction and development, etc. In view of the severity and potential adverse impacts of caffeine pollution in the environment, we proposed that caffeine should be considered as a high-priority environmentally hazardous PhAC pollutant, and it is necessary to implement an ecopharmacovigilance (EPV) program targeting caffeine to minimize its environmental load from a pharmacy perspective.

17.
Cell Biol Int ; 44(2): 536-548, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31642547

RESUMO

Valproate (VPA), an effective clinical approved anti-epileptic drug and mood stabilizer, has been believed to induce neuronal differentiation at the expense of inhibiting astrocytic and oligodendrocytic differentiation. Nevertheless, the involving mechanisms of it remain unclear yet. In the present study, we explored the global gene expression changes of fetus rat hippocampal neural stem cells following VPA treatment by high-throughput microarray. We obtained 874 significantly upregulated genes and 258 obviously downregulated genes (fold change > 2 and P < 0.05). Then, we performed gene ontology and pathway analyses of these differentially expressed genes and chose several genes associated with nervous system according to gene ontology analysis to conduct expression analysis to validate the reliability of the array results as well as reveal possible mechanisms of VPA. To get a better comprehension of the differentially regulated genes by VPA, we conducted protein-protein association analysis of these genes, which offered a source for further studies. In addition, we made the overlap between the VPA-downregulated genes and the predicted target genes of VPA-upregulated microRNAs (miRNAs), which were previously demonstrated. These overlapped genes may provide a source to find functional VPA/miRNA/mRNA axes during neuronal differentiation. This study first constructed a comprehensive potential downstream gene map of VPA in the process of neuronal differentiation.

18.
Environ Sci Technol ; 54(2): 758-767, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31682442

RESUMO

Quantification of extractable antibiotics in soils is important to assessing their bioavailability and mobility, and ultimately their ecotoxicological and health risks. This study aimed to establish a biosensor method for detecting extractable tetracyclines in soils (Alfisol, Mollisol, and Ultisol) using whole-cell biosensors containing a reporter plasmid (pMTGFP or pMTmCherry) carrying fluorescent protein genes tightly controlled by tetracyclines-responsive control region (tetRO). This whole-cell biosensor method can simultaneously measure 96 or more samples within 6 h and is easily parallelizable, whereas a typical high-performance liquid chromatography (HPLC) method may require 7 times more of analysis time and much greater cost to achieve similar analytical throughput. The biosensor method had a detection limit for each of six tetracyclines between 5.32-10.2 µg/kg soil, which is considered adequate for detecting tetracyclines in ethylenediaminetetraacetic acid (EDTA) extracts of soils. Relative standard deviation was between 19.8-51.2% for the biosensor Escherichia coli DH5α/pMTGFP and 2.98-25.8% for E. coli DH5α/pMTmCherry, respectively, suggesting that E. coli DH5α/pMTmCherry was superior to E. coli DH5α/pMTGFP for detecting extractable tetracyclines in soils. This new, fast, easily parallelizable, and cost-effective biosensor method has the potential for measuring extractable concentrations of tetracyclines for a large number of soil samples in large-scale monitoring studies.

19.
Fitoterapia ; 140: 104415, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31704260

RESUMO

Four new sesquiterpenoids, phellinignins A-D (1-4), together with four known ones (5-8), were isolated from cultures of the fungus Phellinus igniarius. The structures were established by extensive spectroscopic methods including MS, NMR, and the single crystal X-ray diffraction. Compounds 1-3 and 5-8 are tremulane sesquiterpenoids, while compound 4 possesses a new carbon skeleton that might derive from an illudane framework. Compounds 1, 2, 4, and 5 showed certain cytotoxicities to three human cancer cell lines.


Assuntos
Antineoplásicos/farmacologia , Basidiomycota/química , Sesquiterpenos/farmacologia , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , China , Humanos , Estrutura Molecular , Sesquiterpenos/isolamento & purificação
20.
Environ Res ; 181: 108899, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31740041

RESUMO

In this work, corn straw (CS) based porous carbon was prepared by one-step phosphoric acid (H3PO4) low temperature activation. The impregnation ratios (H3PO4/CS, g/g) played an important role in the pore development. ACS300-1 engineered at 300 °C and the impregnation ratio of 1.0 showed the maximal specific surface area of 463.89 m2/g with total pore volume of 0.387 cm3/g, attaining a high tetracycline (TC) uptake of 227.3 mg/g. The adsorption of TC onto ACS300-1 was found tolerant with wide pH (2.0-10.0) and high ionic strength (0 - 0.5 M). The adsorption data can be fitted well by the pseudo-second order kinetic model and Langmuir isotherm model. The endothermic and spontaneous properties of the adsorption system was implied by Thermodynamic study. The findings of the current work conclude that one-step H3PO4 activation is a green and promising method for corn straw based porous carbon that may be found with great potentials in antibiotic containing wastewater treatment.

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