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1.
Sci Total Environ ; 954: 176289, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39288879

RESUMO

Cadmium (Cd) is a common additive in polyvinyl chloride (PVC) and polypropylene (PP) plastics. Aquatic organisms were inevitably co-exposed to PVC/PP microplastics (MPs) and Cd, but their combined toxicity is still unknown. In this study, adult zebrafish were exposed to 200 µg/L MPs (PVC or PP) and 10 µg/L Cd alone or in combination for 28 days to investigate their toxicity and mechanisms. Results showed that combined exposure with PVC/PP enhanced the Cd accumulation in the zebrafish intestine. Subsequently, toxicology analyses showed that both PVC and PP possessed synergistic toxicity with Cd, manifested by the exfoliation and necrosis of intestinal epithelial cells, and increased levels of interleukin-1ß (IL-1ß), superoxide dismutase (SOD) and malondialdehyde (MDA). PP exhibited a stronger synergistic effect than PVC. Integration of non-targeted metabolomics and 16S rRNA gene sequencing revealed that combined exposure to PVC and Cd induced intestine toxicity mainly through bile acid (BA) biosynthesis, fructose (Fru) and mannose (Man) metabolism, and pentose phosphate pathway (PPP). The combined exposure of PP and Cd induced toxicity through the arginine (Arg) and glutathione (GSH) metabolisms. Meanwhile, combined exposure of PVC/PP and Cd increased the abundance of intestinal Proteobacteria and pathogen Vibrio, and decreased the abundance of Gemmobacter. These changes indrectly promoted the synergistic toxicity of PVC/PP and Cd through metabolites, such as indole-3-pyruvate (IPyA), chenodeoxycholic acid (CDCA), and cholic acid (CA). These findings highlighted that more attention should be paid to the toxicity of chemicals at environmentally relevant concentrations, particularly those co-existing with MPs.

2.
Food Res Int ; 174(Pt 2): 113672, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37981367

RESUMO

Highland barley (HB) grains are gaining increasing popularity owing to their high nutritional merits. However, only limited information is available on the metabolic profiles of HB grains polyphenols, especially the difference of polyphenols in different colors of HB. In this study, we determined the metabolic profiles of black, blue, and white HB grains via an ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS)-based metabolomics. A total of 402 metabolites were identified, among which 198, 62, and 189 metabolites displayed different accumulation patterns in the three comparison groups (WHB vs. BKHB, WHB vs. BEHB, BEHB vs. BKHB), respectively. In particular, flavonoids and phenolic acids contents displayed considerable differences among the three HB cultivars. The phenolics content of black HB was relatively high. Additionally, "Flavonoid biosynthesis" and "flavone and flavonol biosynthesis" were the significantly enriched pathways. In conclusion, this study provides comprehensive insights into the adequate utilization and development of novel HB-based functional foods.


Assuntos
Hordeum , Polifenóis , Espectrometria de Massas em Tandem , Metabolômica , Fenóis
3.
Int J Clin Pract ; 2023: 3093945, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36756222

RESUMO

Osteosarcoma is the most common malignant bone tumour affecting children and young adults. The antitumour role of propofol, a widely used intravenous sedative-hypnotic agent, has been recently reported in different cancer types. In this study, we aimed to assess the role of propofol on osteosarcoma and explore the possible mechanisms. Propofol of increasing concentrations (2.5, 5, 10, and 20 µg/ml) was used to treat the MG63 and 143B cells for 72 hours, and the CCK8 assay was applied to evaluate the tumour cell proliferation. Tumour cell migration and invasion were assessed with the transwell assay. The tumour cells were also treated with doxorubicin single agent or in combination with propofol to explore their synergic role. Differential expressed genes after propofol treatment were obtained and functionally assessed with bioinformatic tools. Expression of ER stress markers CHOP, p-eIF2α, and XBP1s was evaluated to validate the activation of ER stress response with western blot and qRT-PCR. The statistical analyses were performed with R v4.2.1. Propofol treatment led to significant growth inhibition in MG63 and 143B cells in a dose-dependent manner (p < 0.05). Osteosarcoma migration (MG63 91.4 (82-102) vs. 56.8 (49-65), p < 0.05; 143B 96.6 (77-104) vs. 45.4 (28-54), p < 0.05) and invasion (MG63 68.6 (61-80) vs. 32 (25-39), p < 0.05; 143B 90.6 (72-100) vs. 39.2 (26-55), p < 0.05) were reduced after propofol treatment. Doxorubicin sensitivity was increased after propofol treatment compared with the control group (p < 0.05). Bioinformatic analysis showed significant functional enrichment in ER stress response after propofol treatment. Upregulation of CHOP, p-eIF2α, and XBP1s was detected in MG63 and 143B secondary to propofol treatment. In conclusion, we found that propofol treatment suppressed osteosarcoma proliferation and invasion and had a synergic role with doxorubicin by inducing ER stress. Our findings provided a novel option in osteosarcoma therapy.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Propofol , Humanos , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Proliferação de Células , Doxorrubicina/farmacologia , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , Osteossarcoma/metabolismo , Propofol/farmacologia , Linhagem Celular Tumoral
4.
Sci Rep ; 12(1): 21356, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494378

RESUMO

Neoadjuvant chemotherapy has become one of the important means for advanced hypopharyngeal carcinoma. So far, there is no effective index to predict the curative effect. To investigate the value of iodine map of dual-energy computed tomography (CT) in predicting the efficacy of neoadjuvant chemotherapy for hypopharyngeal carcinoma. A total of 54 hypopharyngeal carcinomapatients who underwent two courses of TPF neoadjuvant chemotherapy were recruited in this study. Three cases had a complete response (CR), thirty-six cases had a partial response (PR), eleven cases had stable disease (SD), and four cases had a progressive disease (PD) after the chemotherapy. All patients underwent a dual-source CT scan before chemotherapy and rescanned after chemotherapy. The normalized iodine-related attenuation (NIRA) of the mean of maximum slice and most enhanced region of lesion at arterial and parenchymal phase were measured: NIRAmean-A, NIRAmax-A, NIRAmean-P, and NIRAmax-P, respectively. Correlation analysis was conducted between different metrics of NIRA and the diameter change rate of lesions, and the curative effect was evaluated based on the receiver operating characteristic (ROC) curve. There were a significant correlation between NIRAmean-A, NIRAmax-A, NIRAmean-P, NIRAmax-P and the change rate of lesion's maximum diameter (ΔD%) (all P < 0.01). The NIRAmax-A, NIRAmean-P, NIRAmax-P had significant differences between CR, PR, SD, PD groups, but NIRAmean-A did not reach a significant difference. All NIRAmean-A, NIRAmax-A, NIRAmean-P, NIRAmax-P had significant differences between effective (CR + PR) and ineffective (SD + PD) groups. The ROC analysis revealed that NIRAmean-P had the largest AUC and prediction efficacy (AUC = 0.809). Dual-energy CT iodine map could predict the efficacy of neoadjuvant chemotherapy and provides imaging evidence to assist in treatment decisions for hypopharyngeal carcinoma patients.


Assuntos
Carcinoma , Neoplasias Hipofaríngeas , Iodo , Humanos , Terapia Neoadjuvante , Iodo/uso terapêutico , Neoplasias Hipofaríngeas/diagnóstico por imagem , Neoplasias Hipofaríngeas/tratamento farmacológico , Tomografia Computadorizada por Raios X/métodos
5.
Front Plant Sci ; 13: 919294, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35979072

RESUMO

Essential oils have attracted wide attention in recent years due to their extensive applications in natural functional ingredients, pharmaceutical preparations, biomedical products, and the cosmetics industry. In this study, the chemical compositions and biological activities of essential oils extracted from six Lamiaceae herbs, including Pogostemon cablin (Blanco) Benth. (PCEO), Perilla frutescens (L.) Britton (PFEO), Salvia japonica Thunb. (SJEO), Rosmarinus officinalis L. (ROEO), Lavandula angustifolia Mill. (LAEO), and Agastache rugosa (Fisch. & C. A. Mey.) Kuntze (AREO), were determined and analyzed. A total of 167 components were identified from the six essential oils by GC-MS analysis, with 35, 24, 47, 46, 54, and 37 components in PCEO, PFEO, SJEO, ROEO, LAEO, and AREO, respectively. Hierarchical cluster analysis of chemical compositions showed that the composition of the six essential oils was significantly different in content, and they were clearly divided into six classes. However, all of these six essential oils exhibited promising anti-inflammatory activity by inhibiting the expression of interleukin-1, interleukin-6, tumor necrosis factor-α, and cyclooxygenase-2 in rats with adjuvant arthritis, among which PFEO had the best performance. In addition, the six essential oils displayed significant cytotoxicity on B16 (IC50 = 86.91-228.91 µg/mL) and LNCaP cell lines (IC50 = 116.4-189.63 µg/mL). Meanwhile, all of them presented satisfactory antioxidant activity (IC50 = 4.88-13.89 µg/mL) compared with Trolox C (IC50 = 13.83 µg/mL), and SJEO (IC50 = 7.93 µg/mL) served as an optimal candidate natural antioxidant by DPPH assay. Taken together, these results indicate that the six Lamiaceae essential oils manifest excellent and diverse biological activities, enabling them to be used as perfect natural functional ingredients in antioxidant, antitumor, or anti-arthritic drugs. This study provides more references for pharmaphylogeny research and drug discovery from folk medicinal plants.

6.
J Plant Physiol ; 277: 153789, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35995002

RESUMO

The citrate content of strawberry fruits affects their organoleptic quality. However, little is known about the transcriptional regulatory mechanisms of citric acid metabolism in strawberry fruits. In this study, the R2R3-MYB transcription factor FaMYB5 was identified and placed in the R2R3-MYB subfamily. FaMYB5 is found in the nucleus and shows tissue- and stage-specific expression levels. Citric acid content was positively correlated with FaMYB5 transcript levels. Upregulated FaMYB5 increased citric acid accumulation in transient FaMYB5-overexpressing strawberry fruits, whereas transient RNA silencing of FaMYB5 in strawberry fruits resulted in a reduction of citric acid content. The role of FaMYB5 was verified using stable transgenic NC89 tobacco. Furthermore, a yeast one-hybrid assay revealed that FaMYB5 influences citric acid accumulation by binding to the FaACO (aconitase), FaGAD (glutamate decarboxylase), and FaCS2 (citrate synthase) promoters. Dual-luciferase assays were used to demonstrate that FaMYB5 could activate FaCS2 expression and repress the transcription levels of FaACO and FaGAD. This study identified important roles of FaMYB5 in the regulation of citric acid metabolism and provided a potential target for improving strawberry fruit taste in horticultural crops.


Assuntos
Fragaria , Aconitato Hidratase/genética , Aconitato Hidratase/metabolismo , Citrato (si)-Sintase/genética , Citrato (si)-Sintase/metabolismo , Ácido Cítrico/metabolismo , Fragaria/metabolismo , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Glutamato Descarboxilase/genética , Glutamato Descarboxilase/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Polymers (Basel) ; 15(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36616405

RESUMO

Enteromorpha, as a waste from marine pollution, brings great pressure to environmental governance every year, especially for China. Under the premise of a shortage of industrial materials, taking appropriate measures can turn waste into wealth, which will benefit us a lot. In this work, a bio-based reinforcing-type flame retardant based on Enteromorpha is designed. The designed Enteromorpha-based flame retardant system (AEG) mainly focuses on the reinforcing and flame retardant effects on ethylene-propylene-diene tripolymer (EPDM). For the AEG system, ammonium polyphosphate (APP) serves as both the acid source and the gas source; the simple hybrid material (GN) produced by loading graphene (GE) and Enteromorpha (EN) using tannic acid (TA) as a regulator serves as an acid source and a carbonizing source. The results show that when 40 phr AEG is added, the LOI of EPDM/AEG40 reaches 32.5% and the UL-94 reaches the V-0 level. The PHRR and THR values of EPDM/AEG40 are 325.9 kW/m2 and 117.6 MJ/m2, respectively, with decrements of 67.3% and 29.7%, respectively, compared with the results of neat EPDM composite. Especially, the TSP and TSR values of EPDM/AEG40 are reduced from 15.2 m2 of neat EPDM to 9.9 m2 with a decrement of 34.9% and reduced from 1715.2 m2/m2 of neat EPDM to 1124.5 m2/m2 with a decrement of 34.4%, indicating that AEG is effective in flame retardancy and smoke suppression. Meanwhile, the tensile strength and tear strength of EPDM/AEG composites are much higher than neat EPDM, therefore, with the future development of innovate reinforcing-type flame-retardant Enteromorpha, the application of Enteromorpha in the polymer flame-retardant field will surely usher in bright development.

8.
J Econ Entomol ; 114(6): 2553-2561, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34546358

RESUMO

Uridine diphosphate glucosyltransferases (UGTs), which are phase II detoxification enzymes, are found in various organisms. These enzymes play an important role in the detoxification mechanisms of plant allelopathy and in insects. Artemisia vulgaris L. (Asterales: Asteraceae: Artemisia) essential oil has strong contact toxicity to Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) larvae. However, the effect of A. vulgaris essential oil on UGTs is unclear. In this study, A. vulgaris essential oil was shown to significantly induce the expression of the TcUgt86Dg transcript. Furthermore, treatment of TcUgt86Dg-silenced individuals with A. vulgaris essential oil resulted in higher mortality than for the control individuals, indicating that TcUgt86Dg is involved in detoxification of A. vulgaris essential oil in T. castaneum. The developmental expression profile showed that the expression of TcUgt86Dg in late adults was higher than in other developmental stages. Furthermore, the expression profile in adult tissues revealed higher expression of TcUgt86Dg in the head, antenna, fat body, and accessory gland than in other tissues. These data show that TcUgt86Dg may be involved in the metabolism of exogenous toxins by T. castaneum; thus, our results have elucidated one possible mechanism of resistance to A. vulgaris essential oil and provide a theoretical basis for a control scheme for T. castaneum.


Assuntos
Artemisia , Besouros , Inseticidas , Óleos Voláteis , Tribolium , Animais , Besouros/genética , Glucosiltransferases , Tribolium/genética , Difosfato de Uridina
9.
Heliyon ; 7(3): e06577, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33855242

RESUMO

Gold nanoparticles (AuNPs) are biocompatible nanomaterials with potential application in the food industry. The safety of AuNPs oral consumption remains inconclusive, and information on possible long-term toxicity is limited. The current study aimed to evaluate the subchronic oral toxicity of AuNPs in male and female Institute of Cancer Research (ICR) mice. Citrate-coated spherical AuNPs with 53 nm diameters were prepared and orally administered to the mice. No mortality or clinical abnormalities were observed following daily administration of AuNPs at the dosages of 0.2, 2, and 20 mg/kg for 90 days. There was no significant difference in body weight or the relative organs' weights between the control and AuNPs-treated mice. No gross abnormalities or histopathological changes were observed except that the male mice treated with high dose (20 mg/kg AuNPs) showed minor infiltration in the kidneys, and female mice showed a reduced A/G ratio and elevated platelet indices. Overall, the 90-day long-term oral consumption of AuNPs did not cause significant toxicity in mice.

10.
Org Biomol Chem ; 18(31): 6126-6133, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32725024

RESUMO

Deuterated molecules feature important biological activities and pharmacokinetic properties for the design of pharmaceuticals. Radical cyclization cascades involving the deuteration of alkenes to form heterocyclic compounds have rarely been reported. Herein, a deuterium addition cascade cyano insertion/cyclization of N-arylacrylamides to synthesize deuterated phenanthridines is described. Cheap Fe(NO3)3·9H2O enables the generation of a deuterium radical from NaBD4in situ. These reactions proceed under mild conditions in a short time and a variety of functional groups are well tolerated.

11.
J Ethnopharmacol ; 260: 113002, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32502652

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Fungal infections remain a serious problem worldwide that require effective therapeutic strategies. Essential oil of basil (Ocimum basilicum L., BEO) being traditionally used extensively for the treatment of bacterial and fungal infection has a long history. However, the potential mechanism of action was still obscure, especially from the metabolic perspective. MATERIALS AND METHODS: The fungistatic effect of BEO on Candida albicans (C. albicans) was evaluated by measurement of minimum inhibitory concentration (MIC) and morphological analysis. A high-coverage microbial metabolomics approach was utilized to identify the alterations of intracellular metabolites of C. albicans at mid-logarithmic growth phase in response to the subinhibitory concentration of BEO, by using gas chromatography coupled to time-of-fight mass spectrometry (GC-TOFMS). Following the metabolic fingerprinting, systematic network analysis was performed to illustrate the potential mechanism of BEO involved in the suppression of C. albicans. RESULTS: The damage in cellular membranes of C. albicans treated by BEO above MIC was observed on the scanning electron microscope (SEM) micrographs. Metabolomics results showed that, among 140 intracellular metabolites identified by comparison with reference standards, thirty-four had significantly changed abundances under 0.2 MIC of BEO treatment, mainly involving in central carbon metabolism (glycolysis/gluconeogenesis, pentose phosphate pathway and TCA cycle), amino acids, polyamines and lipids metabolism. Pathway and network analyses further found that fifteen ingredients of BEO mainly terpenoids and phenyl-propanoids, potentially participated in the metabolic regulation and may be responsible for the suppression of C. albicans. CONCLUSIONS: The findings highlighted that integrated microbial metabolomics and network analyses could provide a methodological support in understanding the functional mechanisms of natural antimicrobial agents and contribute to drug discovery.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Ocimum basilicum/química , Óleos Voláteis/farmacologia , Antifúngicos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Metabolômica , Testes de Sensibilidade Microbiana , Óleos Voláteis/isolamento & purificação
12.
Mar Drugs ; 18(2)2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32079242

RESUMO

In recent years, microalgae have drawn increasing attention as a valuable source of functional food ingredients. Intriguingly, Nitzschia laevis is rich in fucoxanthinol that is seldom found in natural sources. Fucoxanthinol, a marine xanthophyll carotenoid, possesses various beneficial bioactivities. Nevertheless, it's not clear whether fucoxanthinol could exert anti-neuroinflammatory function. In light of these premises, the aim of the present study was to investigate the anti-inflammatory role of fucoxanthinol purified from Nitzschia laevis in Lipopolysaccharide (LPS)-stimulated microglia. The results showed that pre-treatment of fucoxanthinol remarkably attenuated the expression of LPS-induced nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and the production of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), prostaglandin E2 (PGE-2), nitric oxide (NO) and reactive oxygen species (ROS) induction. Modulation mechanism studies revealed that fucoxanthinol hampered nuclear factor-kappa B (NF-κB), Akt, and mitogen-activated protein kinase (MAPK) pathways. Meanwhile, fucoxanthinol led to the enhancement of nuclear translocation of NF-E2-related factor 2 (Nrf2), and the upregulation of heme oxygenase-1 (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQO-1). Taken together, the results indicated that fucoxanthinol obtained from Nitzschia laevis had great potential as a neuroprotective agent in neuroinflammation and neurodegenerative disorders.


Assuntos
Diatomáceas , Inflamação/tratamento farmacológico , Microglia/efeitos dos fármacos , Microglia/metabolismo , beta Caroteno/análogos & derivados , Animais , Anti-Inflamatórios/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Heme Oxigenase-1/metabolismo , Inflamação/induzido quimicamente , Interleucina-6/metabolismo , Lipopolissacarídeos , Proteínas de Membrana/metabolismo , Camundongos , NAD(P)H Desidrogenase (Quinona)/metabolismo , NADPH Oxidases/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , beta Caroteno/química , beta Caroteno/farmacologia
13.
Biochem Biophys Res Commun ; 497(4): 990-996, 2018 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-29462617

RESUMO

Histone deacetylase inhibitors (HDACi) manifest great potential for treatment of Burkitt's lymphoma (BL), an aggressive B-cell lymphoma. Epidermal growth factor receptor pathway substrate 8 (EPS8) is confirmed overexpressed and associated with poor prognosis in solid tumors and leukemia. However, EPS8 expression and the relationship between EPS8 and HDACi on BL remains obscure. Here, we hypothesized that trichostatin A (TSA), a pan-HDACi, could inhibit BL cells by downregulating EPS8. We demonstrated that TSA reduced cell viability, induced apoptosis and cell arrest at G0/G1. Mechanismly, TSA attenuated EPS8 and downstream Phospho-Erk1/2 pathway. Knockdown of EPS8 resulted in a significant reduction in cellular proliferation and suppressed Phospho-Erk1/2 pathway activity, particularly when combined with TSA. Conversely, overexpression of EPS8 rescued this phenomenon. Then we showed that the combination of TSA and Epirubicin had a more significant effect when compared with TSA or Epirubicin alone. Finally, knockdown of EPS8 and TSA had a synergistic suppression effect on BALB/c nude mice. In conclusion, this study reveals that TSA affects BL cells by suppressing Phospho-Erk1/2 pathway through downregulating EPS8.


Assuntos
Linfoma de Burkitt/tratamento farmacológico , Ácidos Hidroxâmicos/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Linfoma de Burkitt/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Epirubicina/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Nus
14.
RSC Adv ; 8(32): 17813-17825, 2018 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35542098

RESUMO

A novel graphene-silicon dioxide hybrid (HGS) was prepared by plant polyphenol-tannic acid (TA) functionalized pristine graphene (G-TA) and primary amine-containing silane coupling agent modified SiO2 (Si-NH2). Through strong hydrogen-bonding interaction between the phenolic hydroxyl groups on G-TA and primary amine groups on Si-NH2, SiO2 was uniformly loaded to the surface of graphene. Due to the synergistic dispersion effect of graphene and SiO2, which prevents restacking and re-aggregating of both graphene and SiO2, HGS hybrids were distributed evenly in the natural rubber (NR) matrix (HGS@NR). Simultaneously, the surface roughness of graphene after loading SiO2 and the interfacial interaction between the HGS hybrid and NR matrix were substantially improved. Due to the good dispersion and strong interface, the overall properties of HGS@NR nanocomposites are drastically enhanced compared with those of GS@NR nanocomposites prepared by dispersing the blend of unmodified graphene and SiO2 (GS) in NR. The HGS@NR nanocomposites possess the highest tensile strength up to 27.8 MPa at 0.5 wt% and tear strength of 60.2 MPa at 0.5 wt%. Thermal conductivities of the HGS@NR nanocomposites were found to be 1.5-fold better than that of the GS@NR nanocomposites. Also, the HGS@NR nanocomposites exhibit excellent abrasive resistant capacity that is nearly 2-fold better than that of the GS@NR nanocomposites. These results suggest that HGS has great potential in high-performance nanocomposites and a new strategy of constructing the efficient graphene-SiO2 hybrid fillers has been established.

15.
J Pak Med Assoc ; 67(12): 1933-1935, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29256547

RESUMO

Pheochromocytoma is rarely seen under the age of 8 years and the anaesthesia for pheochromocytoma surgery is challenging. We present the perioperative management of a 5-year-old boy with intestinal obstruction and two episodes of cerebral haemorrhage who presented for pheochromocytoma resection and enterolysis. Important issues in the management of this patient included choice of vasoactive agents and anaesthetics, control of blood pressure and intracranial pressure, preioperative fluid management, and monitoring technique. Imbalance of fluid and electrolyte disturbance as well as a potentially inevitable drop in blood pressures after complete excision of tumour further complicate patient care. Knowledge of different medical issues involved in this case and their potential impact on anaesthetic management is paramount for safe perioperative patient care.


Assuntos
Neoplasias das Glândulas Suprarrenais/cirurgia , Anestesia/métodos , Feocromocitoma/cirurgia , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Pressão Sanguínea , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/etiologia , Pré-Escolar , Frequência Cardíaca , Humanos , Obstrução Intestinal/diagnóstico por imagem , Obstrução Intestinal/etiologia , Masculino , Monitorização Intraoperatória/métodos , Feocromocitoma/complicações , Feocromocitoma/diagnóstico por imagem
16.
Bioorg Med Chem Lett ; 27(11): 2420-2423, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28433531

RESUMO

Introduction of a Michael acceptor on a flexible scaffold derived from pan-FGFR inhibitors has successfully yielded a novel series of highly potent FGFR4 inhibitors with selectivity over FGFR1. Due to reduced lipophilicity and aromatic ring count, this series demonstrated improved solubility and permeability. However, plasma instability and fast metabolism limited its potential for in vivo studies. Efforts have been made to address these problems, which led to the discovery of compound (-)-11 with improved stability, CYP inhibition, and good activity/selectivity for further optimization.


Assuntos
Acrilamidas/farmacologia , Pirimidinas/farmacologia , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Acrilamidas/administração & dosagem , Acrilamidas/síntese química , Acrilamidas/metabolismo , Animais , Descoberta de Drogas , Estabilidade de Medicamentos , Feminino , Humanos , Camundongos Endogâmicos BALB C , Microssomos Hepáticos/metabolismo , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinas/administração & dosagem , Pirimidinas/síntese química , Pirimidinas/metabolismo , Quinazolinas/farmacologia , Solubilidade , Estereoisomerismo , Relação Estrutura-Atividade
17.
Plant Physiol ; 172(3): 1532-1547, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27663409

RESUMO

Arginine decarboxylase (ADC)-mediated putrescine biosynthesis plays an important role in plant stress responses, but the transcriptional regulation of ADC in response to abiotic stress is not well understood. We isolated a NAM, ATAF1/2, and CUC (NAC) domain-containing transcription factor, PtrNAC72, from trifoliate orange (Poncirus trifoliata) by yeast one-hybrid screening. PtrNAC72, localized to the nucleus, binds specifically to the promoter of PtADC and acts as a transcriptional repressor. PtrNAC72 expression was induced by cold, drought, and abscisic acid. ADC messenger RNA abundance and putrescine levels were decreased in transgenic tobacco (Nicotiana nudicaulis) plants overexpressing PtrNAC72 but increased, compared with the wild type, in an Arabidopsis (Arabidopsis thaliana) transfer DNA insertion mutant, nac72 While transgenic tobacco lines overexpressing PtrNAC72 were more sensitive to drought, plants of the Arabidopsis nac72 mutant exhibited enhanced drought tolerance, consistent with the accumulation of reactive oxygen species in the tested genotypes. In addition, exogenous application of putrescine to the overexpression lines restored drought tolerance, while treatment with d-arginine, an ADC inhibitor, compromised the drought tolerance of nac72 Taken together, these results demonstrate that PtrNAC72 is a repressor of putrescine biosynthesis and may negatively regulate the drought stress response, at least in part, via the modulation of putrescine-associated reactive oxygen species homeostasis.


Assuntos
Adaptação Fisiológica , Secas , Proteínas de Plantas/metabolismo , Poncirus/fisiologia , Putrescina/biossíntese , Fatores de Transcrição/metabolismo , Ácido Abscísico/farmacologia , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Sequência de Aminoácidos , Antioxidantes/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Sequência de Bases , Carboxiliases/metabolismo , Dessecação , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Mutação/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Poncirus/efeitos dos fármacos , Poncirus/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Repressoras/metabolismo , Alinhamento de Sequência , Análise de Sequência de Proteína , Estresse Fisiológico/genética , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo , Nicotiana/genética , Fatores de Transcrição/química , Fatores de Transcrição/genética , Técnicas do Sistema de Duplo-Híbrido
18.
J Org Chem ; 81(6): 2482-7, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26916233

RESUMO

A regioselective alkoxycarbonylation of imidazoheterocycles using carbazates as ester group sources in DMSO was developed, in which an inexpensive FeCl2·4H2O was used as the catalyst and (NH4)2S2O8 was the oxidant. The reaction proceeded smoothly under an air atmosphere to give the 3-alkoxycarbonylated products in moderate to good yields.

19.
PLoS One ; 9(11): e112245, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25423588

RESUMO

BACKGROUND: The seagrass Zostera marina is a monocotyledonous angiosperm belonging to a polyphyletic group of plants that can live submerged in marine habitats. Zostera marina L. is one of the most common seagrasses and is considered a cornerstone of marine plant molecular ecology research and comparative studies. However, the mechanisms underlying its adaptation to the marine environment still remain poorly understood due to limited transcriptomic and genomic data. PRINCIPAL FINDINGS: Here we explored the transcriptome of Z. marina leaves under different environmental conditions using Illumina paired-end sequencing. Approximately 55 million sequencing reads were obtained, representing 58,457 transcripts that correspond to 24,216 unigenes. A total of 14,389 (59.41%) unigenes were annotated by blast searches against the NCBI non-redundant protein database. 45.18% and 46.91% of the unigenes had significant similarity with proteins in the Swiss-Prot database and Pfam database, respectively. Among these, 13,897 unigenes were assigned to 57 Gene Ontology (GO) terms and 4,745 unigenes were identified and mapped to 233 pathways via functional annotation against the Kyoto Encyclopedia of Genes and Genomes pathway database (KEGG). We compared the orthologous gene family of the Z. marina transcriptome to Oryza sativa and Pyropia yezoensis and 11,667 orthologous gene families are specific to Z. marina. Furthermore, we identified the photoreceptors sensing red/far-red light and blue light. Also, we identified a large number of genes that are involved in ion transporters and channels including Na+ efflux, K+ uptake, Cl- channels, and H+ pumping. CONCLUSIONS: Our study contains an extensive sequencing and gene-annotation analysis of Z. marina. This information represents a genetic resource for the discovery of genes related to light sensing and salt tolerance in this species. Our transcriptome can be further utilized in future studies on molecular adaptation to abiotic stress in Z. marina.


Assuntos
Genes de Plantas , Transcriptoma , Zosteraceae/metabolismo , Anotação de Sequência Molecular , Fotorreceptores de Plantas/genética , Tolerância ao Sal , Zosteraceae/genética
20.
Med Mycol ; 52(8): 798-803, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25288652

RESUMO

Pneumocystis carinii pneumonia (PcP) is a common and potentially fatal opportunistic infection in immunosuppressed patients, and the standard trimethoprim-sulfamethoxazole (TMP-SMZ) treatment has serious side effects. The cell wall of the causative fungal pathogen is enriched in 1-3-ß-D-glucan, providing an alternative therapeutic target. We directly compared the efficacy of the 1,3-ß-D-glucan synthase inhibitor caspofungin to TMP-SMZ for promoting survival and reducing lung cyst number during the early phase of treatment in a rat model of PcP. Rats were immunosuppressed using dexamethasone for 8 weeks and PcP infection confirmed in test animals by lung print smear. The remaining rats were randomly divided into three control groups, a baseline group and two observed for 7 or 14 days, two caspofungin groups treated intravenously for 7 or 14 days (1 mg/kg/d), and 2 TMP-SMZ positive control groups treated by oral gavage for 7 or 14 days (300 mg/kg/d). Mortality was markedly reduced by both caspofungin and TMP-SMZ after 14 days (caspofungin: 20.0%, TMP-SMZ: 13.3%, Control: 40.0%). Body weight gain in caspofungin-treated rats after 7 (3.04 ± 3.54%) and 14 (4.27 ± 2.79%) days was similar to that in TMP-SMZ-treated rats (3.35 ± 1.88% and 5.85 ± 2.78%, respectively), whereas untreated controls showed weight loss. Lung weight to body weight ratio, and mean cyst number per 50 microscopic fields were significantly lower (all P < 0.05) in caspofungin-treated rats than untreated controls at both 7 and 14 days, and similar to those in the TMP-SMZ-treated rats (all P > 0.05 vs. caspofungin). Caspofungin exhibited similar efficacy to TMP-SMZ for enhancing survival and reducing lung edema and cyst load in a rat model of PcP, suggesting potential clinical utility against PcP.


Assuntos
Antifúngicos/farmacologia , Equinocandinas/farmacologia , Pneumocystis carinii/efeitos dos fármacos , Pneumonia por Pneumocystis/tratamento farmacológico , Animais , Antifúngicos/uso terapêutico , Peso Corporal/efeitos dos fármacos , Caspofungina , Equinocandinas/uso terapêutico , Lipopeptídeos , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Pulmão/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Pneumonia por Pneumocystis/microbiologia , Pneumonia por Pneumocystis/patologia , Ratos
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