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1.
Front Oncol ; 14: 1302196, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38434689

RESUMO

Objective: The aim of this report was to comprehensively investigate the clinicopathological features, histological characteristics, and differential diagnosis of tall cell carcinoma with reversed polarity of the breast (TCCRP) to enhance the understanding of this tumour for precise therapeutic interventions. Methods: The clinicopathological characteristics and differential diagnosis of a patient with TCCRP were retrospectively analysed, and a systematic literature review was extracted from relevant published studies on PubMed. Results: All patients included in the study were female, with a median age of 51 years. Microscopically, the tumour cells exhibited a solid papillary growth pattern with tall columnar morphology and reversed nuclear polarity. Immunohistochemistry revealed that the tumours were triple-negative breast cancer (negative for ER, PR, and HER-2), with a low Ki-67 proliferation index. Different degrees of expression were observed for CK7, Calretinin, and S-100 markers; however, CK5/6 showed high expression levels. Conclusions: TCCRP is an uncommon invasive carcinoma subtype found in the breast. Its histological morphology resembles that of tall cell subtype papillary thyroid carcinoma. Accurate diagnosis requires the integration of histomorphological assessment along with immunohistochemistry and molecular genetics analysis.

2.
Front Oncol ; 14: 1346964, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38482206

RESUMO

Pancreatoblastoma (PB) is a rare malignant pancreatic epithelial tumor that mostly occurs in children and occasionally occurs in adults. The tumor has acinar cell differentiation and squamous corpuscles/squamous epithelial islands, which are frequently separated by fibrous bundles. Familial adenomatous polyposis (FAP) is an autosomal dominant inherited disease characterized by the presence of numerous adenomatous polyps in the colon and rectum. Cases of pancreatoblastoma combined with familial adenomatous polyposis (FAP) are rarely reported. A review of a rare case of adult pancreatoblastoma with atypical histological morphology combined with familial adenomatous polyposis is presented herein. In this case, the patient was first diagnosed with familial adenomatous polyposis and subsequently found to have pancreatoblastoma 1 year and 3 months later. This suggests pancreatoblastoma may occur in patients with familial adenomatous polyposis or a family history of the condition, indicating a possible association between the two tumors. Therefore, pancreatoblastoma should be included in a differential diagnosis for FAP patients with a pancreatic mass. The final diagnosis of pancreatoblastoma depends on the pathological diagnosis. Acinar-like cells and squamous corpuscles/squamous epithelial cell islands under light microscopy are the key diagnostic points. This case report also can improve the awareness of clinicians, radiologists, and pathologists on the presence of rare tumor-adult pancreatoblastoma in patients with familial adenomatous polyposis.

3.
Dalton Trans ; 52(44): 16184-16188, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37870873

RESUMO

Various naphthalenediimide (NDI) based electron donor-acceptor coordination polymers (D-A CPs) have been constructed and used to explore charge transfer (CT) and electron transfer (ET) behaviors. Up to now, significant progress has been made in the interface contact and electron donor-acceptor ability matching mechanism, while the electronic density effect of the electron donors on the CT and ET behaviors is still not known. Herein, two NDI-based D-A CPs, [Cd2(H2NDI)(IPA)2(H2O)2] (1) and [Cd2(H2NDI)(IPA-OH)2(H2O)2] (2), are constructed using an NDI-based ligand and two aromatic carboxylic acid ligands (H2NDI = 2,7-bis(3,5-dimethyl) dipyrazol-1,4,5,8-naphthalene tetracarboxydiimide, H2IPA = isophthalic acid; and H2IPA-OH = 5-hydroxyisophthalic acid). UV-vis and EPR spectroscopy and DFT calculations analyses reveal that the occurrence of themal electron transfer (TET) in 1 and 2 results from the HOMO of the IPA and IPA-OH lying higher than the LUMO of the NDI. Meanwhile, compared to 1, the UV-vis absorption spectrum of 2 exhibits a significant red shift, which suggests higher electron density of the donor and more electron transfer pathways are beneficial for the occurrence of intermolecular CT. After UV light irradiation, the comparison of the photochromic behavior of 1 and 2 confirms the negative effect of the stronger CT on photoinduced electron transfer (PET). The present study illustrates the delicate modulating effect of electron density on the CT and ET behaviors in D-A CPs.

4.
Zhongguo Zhong Yao Za Zhi ; 48(2): 336-348, 2023 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-36725223

RESUMO

As a biocatalyst, enzyme has the advantages of high catalytic efficiency, strong reaction selectivity, specific target products, mild reaction conditions, and environmental friendliness, and serves as an important tool for the synthesis of complex organic molecules. With the continuous development of gene sequencing technology, molecular biology, genetic manipulation, and other technologies, the diversity of enzymes increases steadily and the reactions that can be catalyzed are also gradually diversified. In the process of enzyme-catalyzed synthesis, the majority of common enzymatic reactions can be achieved by single enzyme catalysis, while many complex reactions often require the participation of two or more enzymes. Therefore, the combination of multiple enzymes together to construct the multi-enzyme cascade reactions has become a research hotspot in the field of biochemistry. Nowadays, the biosynthetic pathways of more natural products with complex structures have been clarified, and secondary metabolic enzymes with novel catalytic activities have been identified, discovered, and combined in enzymatic synthesis of natural/unnatural molecules with diverse structures. This study summarized a series of examples of multi-enzyme-catalyzed cascades and highlighted the application of cascade catalysis methods in the synthesis of carbohydrates, nucleosides, flavonoids, terpenes, alkaloids, and chiral molecules. Furthermore, the existing problems and solutions of multi-enzyme-catalyzed cascade method were discussed, and the future development direction was prospected.


Assuntos
Alcaloides , Produtos Biológicos , Produtos Biológicos/química , Catálise , Biocatálise
5.
Curr Oncol ; 30(2): 1784-1793, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36826099

RESUMO

OBJECTIVE: To explore the clinicopathological features of solitary fibrous tumors (SFTs) of the lung. METHODS: We collected the clinical data of 52 patients with SFTs of the lung confirmed by pathology, and summarized the clinical, radiological, and morphological features, the immunophenotypes, and the prognosis of SFTs. RESULTS: Fifty-two cases of SFTs of the lung were enrolled in this study, including 51 cases of borderline and 1 case of malignancy, 22 males and 30 females. The average onset age was 52.7 years. The lower lobe of the left lung was the preferred site of SFTs, accounting for 30.77% (16/52). Chest CT showed regular and well-demarcated soft tissue density mass, and the tumor size of most cases (46/52, 88.46%) was 1-10 cm. Morphological features: The distribution of tumor cells showed sparse and dense areas. Tumor cells were spindle-shaped, in whorls or hemangiopericytoma-like conformation. Atypia, mitotic figures, and necrosis were found. Immunohistochemistry showed positive expression of CD34, STAT6, Vimentin, BCL2, and CD99. Ki-67 was ≤ 5% in borderline SFTs and >20% in a malignant SFT. CONCLUSIONS: Solitary fibrous tumors of the lung occur more frequently in middle-aged and elderly people, and there is no significant difference in gender. The lower lobe of the left lung is the preferred site of SFTs. The size of most SFTs is 1-10 cm. Chest CT shows morphologically regular and well-demarcated soft tissue density mass. Pathologically, SFTs of the lung are mostly borderline and occasionally malignant. Immunohistochemistry shows the positive expression of CD34, STAT6, Vimentin, BCL2, and CD99.


Assuntos
Febre Grave com Síndrome de Trombocitopenia , Tumores Fibrosos Solitários , Idoso , Pessoa de Meia-Idade , Masculino , Feminino , Humanos , Vimentina , Biomarcadores Tumorais/análise , Tumores Fibrosos Solitários/genética , Tumores Fibrosos Solitários/metabolismo , Tumores Fibrosos Solitários/patologia , Pulmão/patologia , Proteínas Proto-Oncogênicas c-bcl-2
6.
Front Plant Sci ; 13: 1008198, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212350

RESUMO

Sorghum [Sorghum bicolor (L.) Moench] is an important crop for food security in semiarid and arid regions due to its high tolerance to abiotic and biotic stresses and its good performance in marginal lands with relatively low fertility. To deeply understand the interrelationship among sorghum genotype, environment, sowing dates, and densities in the spring sowing early maturing (SSEM) areas of China, and to provide a basis for specifying scientific and reasonable cultural practices, a two-year field experiment was conducted with six popular varieties at six locations. Combined ANOVA showed that the yield difference between years was significant (P<0.05); the yield differences among locations, varieties, sowing dates, and densities were all highly significant (P<0.01). The variety effect was mainly influenced by location, year, sowing dates and their interactions. The sowing effect was mainly influenced by the location, year, variety and their interactions The plant density effect was significantly influenced by location and location-year interaction. Of the contributions of various test factors to yield variance, the location was the largest one (38.18%), followed by variety (12.31%), sowing date (1.53%), density (0.54%), and year (0.09%), with all these single factors accounting for 52.65%. The total contribution of all two-factor interactions accounted for 14.24%, among which the greatest contributor was location-hybrid interaction (8.07%). The total contribution of all three-factor interactions accounted for 14.58%, of which year-location-hybrid interaction was the largest contributor (9.02%). Sowing dates significantly affected model of sorghum growth and development, especially during the late period. The key climatic factors affecting yield were different among the six locations. Weather factors during the grain filling stages contributed much more than those during the early stage to grain yield. Mid-maturing varieties are recommended other than early maturing varieties for the SSEM areas even when late sowing occurs. Sowing as early as possible is recommended for areas with very short frost-free period (Harbin, Tongliao, and Datong). Proper delayed sowing is recommended for areas with a relative long frost-free period (Gongzhuling, Baicheng and Zhangjiakou). This research will provide a conducive reference for sorghum production in similar areas.

7.
Front Oncol ; 12: 942517, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35928869

RESUMO

Objective: To investigate the clinical manifestations, radiologic features, pathological features, and immunophenotype of minute pulmonary meningothelial-like nodules (MPMNs). Method: This is a retrospective observational study. We collected the clinical data of 7 cases of MPMNs, and performed comprehensive characterization using a combination of clinical, morphological, radiologic and immunohistochemical assessments. Results: Of the 7 cases of MPMNs, 6 were female and 1 was male. The median age was 55 years. All MPMNs were multiple in lung with the size from 0,01 to 0,5cm. Chest CT examination showed ground-glass attenuation or solid nodules. Four cases were concomitant with carcinoma and/or pneumonia, and 3 cases occurred alone. Four of the 7 patients had no obvious symptoms; 3 patients had chest pain or cough or shortness of breath or hemoptysis. Multiple white nodules were found macroscopically, and the diseased cells grew along the alveolar septum, with relatively normal morphology, rich cytoplasm, unclear cell boundary, and uniform nucleus with delicate chromatin and without atypia; and the diseased cells showed nest or whorls distribution. EMA, PR, CD56 and vimentin were positive in all cases by immunohistochemistry. Conclusions: MPMNs are rare benign lesions in the lung, often multiple, usually less than 0.5cm in diameter, most of which have no obvious clinical symptoms. MPMNs are often found by chest CT, and occur independently or concomitant with other lesions. The positive immunohistochemical staining of EMA, PR, CD56, vimentin supports the diagnosis.

8.
Dalton Trans ; 50(5): 1740-1745, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33459307

RESUMO

The design and utilization of dual sites for synergistic catalysts has been recognised as an efficient method towards high-efficiency catalysis in the cyanosilylation of aldehydes, which gives key intermediates for the synthesis of a number of valuable natural and pharmaceutical compounds. However, most of the reported dual-site catalysts for this reaction were homogeneous, accompanied by potential deactivation through internal complexation of the dual sites. Herein, by the rational selection of an uncoordinated tertiary nitrogen based tricarboxylic ligand (tris[(4-carboxyl)-phenylduryl]amine, H3TCBPA), a new three-dimensional calcium-based metal-organic framework (MOF), Ca3(TCBPA)2(DMA)2(H2O)2 (1, where TCBPA = ionized tris[(4-carboxyl)-phenylduryl]amine and DMA = N,N-dimethylacetamide), possessing accessible dual catalytic sites, Lewis-basic N and Lewis-acidic Ca, has been designed and constructed by a one-pot solvothermal reaction. As expected, 1 is capable of dually and heterogeneously catalysing the cyanosilylation of aldehydes at room temperature, and can be reused for at least 6 runs with a maximum turnover number (TON) of 1301, which is superior to most reported cases. Additionally, 1 shows CO2 adsorption ability and conversion with epoxides, which is beneficial for the establishment of a sustainable society.

9.
Dalton Trans ; 49(40): 13958-13961, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33021307

RESUMO

Discrete supertetrahedral clusters of metal chalcogenides are rare because of the difficulty involved in meeting global charge matching between the negative charge of the skeleton and counterion. We present herein the third type of a discrete chalcogenide cluster with a double T3 structure in the compound (HDBN)6[In20S33(DBN)6] (DBN = 1,5-diazabicyclo [4.3.0]-5-nonene), the anion of which features quasi-D3 symmetrical double-T3 In20S33 supertetrahedra with six cornered indium atoms coordinated by DBN molecules. DFT theory calculations of the interaction between host and guest show that this compound may have high kinetic stability and low photoelectric reactivity.

10.
Inorg Chem ; 58(24): 16785-16791, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31800233

RESUMO

Sensitization with dyes is the most promising option to narrow the band gap and improve visible-light absorption of TiO2. As ideal structure and reaction models of TiO2, titanium oxo clusters (TOCs) with exact crystal structure are beneficial for further understanding the structure-property relationship of TiO2. Most reports mainly focus on the synthesis and properties of TOCs, but research on the band-gap tuning of TOCs at the large range of 3.7-2.0 eV by chromophore ligands (CLs) has been lacking. Herein, six new Ti6-core-based TOCs (Ti6-TOCs) were successfully synthesized by using CLs in a simple and general approach. Each Ti6-TOC structure contains two Ti3(µ3-O) units featuring a flat or pyramidal mode as building blocks. Five Ti6-core structure types were present among the six Ti6-TOCs, which enriched the family of hexanuclear TOCs. To be noted, the band-gap values were tuned at a wide range of 3.41-1.98 eV by controlling the type and number of the CLs 2-hydroxypyridine, salicylaldoxime, and catechol in the structure. Density functional theory calculation revealed that the lowest-energy bands of these Ti6-TOCs are attributed to the CL-to-TiO core charge-transfer bands. This work provides a precise and wide-ranged band-gap tuning method for TOCs. Additionally, the six Ti6-TOCs exhibit good photocurrent response.

11.
Food Chem ; 260: 27-36, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29699669

RESUMO

This study investigated the structure, antioxidant activity, antityrosinase activity and mechanism of proanthocyanidins from mung bean seed [Vigna radiata (L.) Wilczek]. The structural composition were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), electrospray ionization-full-mass spectrometry (ESI-Full-MS), and high-pressure liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) techniques. The mung bean seed proanthocyanidins were composed of procyanidins, prodelphinidins, and their rhamnosides. According to enzyme kinetic analysis, these compounds were potent, reversible, and mixed-type inhibitors of tyrosinase. They inhibited the enzyme activity by interacting with enzyme as well as substrates. The results of molecular docking showed that the interaction between mung bean seed proanthocyanidins and tyrosinase was driven by hydrogen bond, hydrophobic and electrostatic interactions. In addition, mung bean seed proanthocyanidins were demonstrated as powerful antioxidants. Therefore, this study confirmed a novel tyrosinase inhibitor and would lay a scientific foundation for their utilization in pharmaceutical and food industries.


Assuntos
Antioxidantes/farmacologia , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Proantocianidinas/farmacologia , Vigna/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão/métodos , Inibidores Enzimáticos/química , Cinética , Simulação de Acoplamento Molecular , Estrutura Molecular , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/metabolismo , Proantocianidinas/química , Sementes/química , Sementes/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
12.
J Agric Food Chem ; 66(4): 908-917, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29313327

RESUMO

In this study, the content, structure, antityrosinase activity, and mechanism of longan bark condensed tannins were evaluated. The findings obtained from mass spectrometry demonstrated that longan bark condensed tannins were mixtures of procyanidins, propelargonidins, prodelphinidins, and their acyl derivatives (galloyl and p-hydroxybenzoate). The enzyme analysis indicated that these mixtures were efficient, reversible, and mixed (competitive is dominant) inhibitor of tyrosinase. What's more, the mixtures showed good inhibitions on proliferation, intracellular enzyme activity and melanogenesis of mouse melanoma cells (B16). From molecular docking, the results showed the interactions between inhibitors and tyrosinase were driven by hydrogen bond, electrostatic, and hydrophobic interactions. In addition, high levels of total phenolic and extractable condensed tannins suggested that longan bark might be a good source of tyrosinase inhibitor. This study would offer theoretical basis for the development of longan bark condensed tannins as novel food preservatives and medicines of skin diseases.


Assuntos
Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Casca de Planta/química , Sapindaceae/química , Taninos/química , Taninos/farmacologia , Animais , Antocianinas/farmacologia , Biflavonoides/farmacologia , Catequina/farmacologia , Proliferação de Células/efeitos dos fármacos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Espectrometria de Massas , Melaninas/análise , Melaninas/antagonistas & inibidores , Melaninas/biossíntese , Melanoma Experimental , Camundongos , Modelos Moleculares , Simulação de Acoplamento Molecular , Oxirredutases , Parabenos/farmacologia , Proantocianidinas/farmacologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Eletricidade Estática , Relação Estrutura-Atividade
13.
Biochem Biophys Res Commun ; 495(4): 2396-2403, 2018 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-29278701

RESUMO

Pulmonary fibrosis (PF) is a chronic and ultimately fatal interstitial lung disease of various causes. The advent of nintedanib and pirfenidone provides treatment options for PF patients for the first time. However, the adverse effects of the two drugs such as gastrointestinal disorders and hepatic dysfunction often lead to treatment discontinuation. Gentiopicroside (GPS) is a natural secoiridoid glycoside from gentian species of medicinal plants, and has a variety of pharmacological activities, including hepatoprotective and cholagogic, anti-inflammatory, antinociceptive, and smooth muscle relaxing activities. The present study aimed to investigate the therapeutical effects of GPS on bleomycin (BLM)-induced PF in mice. Severe lung inflammation and fibrosis were observed in BLM-treated mice. GPS significantly ameliorated inflammatory and fibrotic responses in lungs of PF mice which were confirmed by histopathological examinations including light microscopy and transmission electron microscopy. Additionally, GPS significantly decreased the levels of inflammatory cytokines including TNF-α and IL-1ß in bronchoalveolar lavage fluid and reduced the content of hydroxyproline in lungs of PF mice. Furthermore, GPS significantly downregulated the expression of TGF-ß1 and CTGF in lungs of PF mice. In vitro, GPS inhibited epithelial-mesenchymal transition of A549 cells stimulated by TGF-ß1, in a dose-dependent manner. Our findings suggest that GPS has the potential as an ideal drug candidate for PF, as it has both anti-inflammatory and anti-fibrotic effects. Alveolar epithelial cells and TGF-ß1 may be the main target cells and molecule of GPS on BLM-induced PF, respectively.


Assuntos
Glucosídeos Iridoides/administração & dosagem , Pulmão/imunologia , Pneumonia/imunologia , Pneumonia/prevenção & controle , Fibrose Pulmonar/imunologia , Fibrose Pulmonar/prevenção & controle , Animais , Anti-Inflamatórios/administração & dosagem , Bleomicina , Citocinas/imunologia , Relação Dose-Resposta a Droga , Fatores Imunológicos/imunologia , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Pneumonia/induzido quimicamente , Fibrose Pulmonar/induzido quimicamente , Resultado do Tratamento
14.
Food Res Int ; 100(Pt 1): 731-739, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28873743

RESUMO

In this study, the structure of proanthocyanidins purified from cherimoya (Annona squamosa) pericarp was analyzed by ESI-QTOF-MS and HPLC analyses. The result indicated that these compounds were procyanidin-type proanthocyanidins, consisting mainly of (epi)catechin units linked b y B-type interflavan bonds. The analyses of enzymology showed that the activities of monophenolase and diphenolase of tyrosinase could be powerfully inhibited by the proanthocyanidins. Further researches on the inhibition mechanism demonstrated that they were reversible and competitive inhibitors with the KI value of 27.1±3.1µg/mL. These inhibitors quenched the fluorescence of tyrosinase through a static quenching mechanism and spontaneously formed proanthocyanidins-enzyme complex. Fluorescence changes of proanthocyanidins in the presence of copper ion suggested that the interactions could reduce the fluorescence intensity of these polymers and the molecular docking analysis revealed that copper irons of the enzyme could be chelated by adjacent hydroxyl groups on the B ring of proanthocyanidins. Moreover, proanthocyanidins were proved to be efficient quencher of substrates. These results would lay scientific foundation for their farther application in food and medicine industry.


Assuntos
Annonaceae/química , Inibidores Enzimáticos/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/química , Proantocianidinas/química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Frutas/química , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/metabolismo , Proantocianidinas/metabolismo , Proantocianidinas/farmacologia , Espectrometria de Fluorescência , Espectrometria de Massas por Ionização por Electrospray
15.
Int J Biol Macromol ; 102: 425-430, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28414110

RESUMO

In this study, the inhibitory effect and mechanism of rifampicin on the activity of tyrosinase were investigated for developing a novel tyrosinase inhibitor. It was found to have a significant inhibition on the activity of tyrosinase (IC50=90±0.6µM). From the kinetics analysis, it was proved to be a reversible and noncompetitive type inhibitor of the enzyme with the KI value of 94±3.5µM. The results obtained from intrinsic fluorescence quenching indicated that rifampicin could interact with tyrosinase. In particular, the drastic decrease of fluorescence intensity was due to the formation of a rifampicin-enzyme complex in a static procedure which was mainly driven by hydrophobic forces and hydrogen bonding. Moreover, the ANS-binding fluorescence analysis suggested that rifampicin binding to tyrosinase changed the polarity of the hydrophobic regions. Molecular docking analysis further revealed that the hydrogen bonds were generated between rifampicin and amino residues Leu7, Ser52, and Glu107 in the B chain of the enzyme. And the hydrophobic forces produced through the interaction of rifampicin with B chain residues Pro9, Pro14, and Trp106. This work identified a novel tyrosinase inhibitor and potentially contributed to the usage of rifampicin as a potential hyperpigmentation drug.


Assuntos
Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Rifampina/farmacologia , Agaricales/enzimologia , Inibidores Enzimáticos/metabolismo , Cinética , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/metabolismo , Conformação Proteica , Rifampina/metabolismo
16.
Food Funct ; 8(3): 1043-1051, 2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28128839

RESUMO

Fruit pericarp of Clausena lansium (Lour.) Skeels, a food waste, was selected as a raw material for proanthocyanidins. The proanthocyanidins' structures were integrally analyzed using three methods: matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), high performance liquid chromatography electrospray ionization mass spectrometry (HPLC-ESI-MS) and 13C nuclear magnetic resonance (NMR). The results elucidated that these compounds were composed of prodelphinidin (75%) and procyanidin (25%) with a degree of polymerization (DP) up to the 20-mers. They were proved to be remarkable, reversible and mixed competitive inhibitors of tyrosinase according to results from enzyme experiments. The IC50 values were calculated to be 23.6 ± 1.2 and 7.0 ± 0.2 µg mL-1 for the monophenolase and diphenolase activities, respectively. In addition, the proanthocyanidins had a good inhibitory effect on cell proliferation, cellular tyrosinase activity and melanin production of B16 mouse melanoma cells. Chelation between the hydroxyl group on the B ring of the proanthocyanidins and dicopper irons of the enzyme provided one of the feasible mechanisms for the inhibition on the basis of fluorescence quenching and molecular docking analyses. This research would supply the scientific basis to these compounds application in the pharmaceutical, insecticides, and preservative fields.


Assuntos
Clausena/química , Inibidores Enzimáticos/química , Frutas/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Extratos Vegetais/química , Proantocianidinas/química , Animais , Linhagem Celular , Sobrevivência Celular , Células/efeitos dos fármacos , Células/enzimologia , Cromatografia Líquida de Alta Pressão , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Cinética , Camundongos , Estrutura Molecular , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Proantocianidinas/isolamento & purificação , Proantocianidinas/farmacologia , Espectrometria de Massas por Ionização por Electrospray
17.
Asian Pac J Cancer Prev ; 15(4): 1675-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24641388

RESUMO

OBJECTIVES: MicroRNAs (miRNAs) are important regulators of many physiological and pathological processes, including tumorigenesis and metastasis. In this study, we sought to determine the underlying molecular mechanisms of metastatic cervical carcinoma by performing miRNA profiling. METHODS: Tissue samples were collected from ten cervical squamous cancer patients who underwent hysterectomy and pelvic lymph node (PLN) dissection in our hospital, including four PLN-positive (metastatic) cases and six PLN-negative (non-metastatic) cases. A miRNA microarray platform with 1223 probes was used to determine the miRNA expression profiles of these two tissue types and case groups. MiRNAs having at least 4-fold differential expression between PLN-positive and PLN-negative cervical cancer tissues were bioinformatically analyzed for target gene prediction. MiRNAs with tumor-associated target genes were validated by quantitative reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Thirty-nine miRNAs were differentially expressed (>4-fold) between the PLN-positive and PLN-negative groups, of which, 22 were up-regulated and 17 were down-regulated. Sixty-nine percent of the miRNAs (27/39) had tumor-associated target genes, and the expression levels of six of those (miR-126, miR-96, miR-144, miR-657, miR-490-5p, and miR-323-3p) were confirmed by quantitative (q)RT-PCR. CONCLUSIONS: Six MiRNAs with predicted tumor-associated target genes encoding proteins that are known to be involved in cell adhesion, cytoskeletal remodeling, cell proliferation, cell migration, and apoptosis were identified. These findings suggest that a panel of miRNAs may regulate multiple and various steps of the metastasis cascade by targeting metastasis-associated genes. Since these six miRNAs are predicted to target tumor-associated genes, it is likely that they contribute to the metastatic potential of cervical cancer and may aid in prognosis or molecular therapy.


Assuntos
Carcinoma de Células Escamosas/genética , MicroRNAs/biossíntese , MicroRNAs/genética , Metástase Neoplásica/genética , Neoplasias do Colo do Útero/genética , Adulto , Idoso , Apoptose/genética , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Adesão Celular/genética , Movimento Celular/genética , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Histerectomia , Excisão de Linfonodo , Pessoa de Meia-Idade , Prognóstico , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/cirurgia
18.
Dalton Trans ; 42(19): 7196-203, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23525352

RESUMO

Using a hemi-rigid multitopic ligand, 1,3,5-triazine-2,4,6-triyltrithio-triacetic acid (H(3)L), three metal(II)-complexes formulated as Pb2L(ox)(1/2)(H2O) (H2ox = oxalic acid) (1), Pb3L2(H2O)2 (2) and Ni6L4(PEP)6(H2O)12·7H2O (PEP = 4-(2-(pyridin-4-yl)ethyl)pyridine) (3) have been hydro(solvo)thermally synthesized and structurally characterized by single-crystal X-ray diffraction. Complex 1 features a novel 4-nodal (3, 4, 5, 6)-connected 3D framework with an unusual (4(2).6(3).8)(4(2).6(8))2(4(2).6)2(4(3).6(11).8)2 topology and complex 2 presents a 3-nodal (5, 6, 8)-connected 3D framework with a novel (3.4(4).5(3).6(2))(3(3).4(12).5(5).6(8))(3(5).4(7).5(3)) topology. Complexes 1 and 2 are hybrid Pb oxides, in which a 2D Pb-O-Pb layer is observed. Complex 3 shows a 3-nodal (3, 4)-connected 3D framework with a novel (6.7(2))2(6(4).7.8)2(7(4).8.10) topology. L(3-)displays different coordination modes in the three complexes. Complexes 1 and 2 show different UV absorptions, emission spectra, photoluminescence lifetimes and they are photocatalytically active for the decomposition of methyl orange (MO) under UV light irradiation.

19.
Huan Jing Ke Xue ; 34(12): 4712-7, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-24640913

RESUMO

Internal floating roof tank has the advantages of external floating roof tank and fixed roof tank and has its own evaporation loss properties. The influences of volatile organic compounds (VOCs) distribution gradient, molecular diffusion, thermal diffusion and forced convection on the evaporation loss of oil were studied in the space of the homemade platform of an internal floating roof tank. The results showed that thermal diffusion with temperature change was the main cause for the static loss in the internal floating roof tank. On this basis, there were some measures for reduction of the evaporation loss and formulas to calculate the evaporation loss of the internal floating roof tank in this research.


Assuntos
Poluentes Atmosféricos/análise , Eliminação de Resíduos/instrumentação , Compostos Orgânicos Voláteis/análise , Difusão , Monitoramento Ambiental
20.
Inorg Chem ; 51(6): 3540-7, 2012 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-22376199

RESUMO

A novel oxonitridosilicate phosphor host Sr(3)Si(2)O(4)N(2) was synthesized in N(2)/H(2) (6%) atmosphere by solid state reaction at high temperature using SrCO(3), SiO(2), and Si(3)N(4) as starting materials. The crystal structure was determined by a Rietveld analysis on powder X-ray and neutron diffraction data. Sr(3)Si(2)O(4)N(2) crystallizes in cubic symmetry with space group Pa ̅3, Z = 24, and cell parameter a = 15.6593(1) Å. The structure of Sr(3)Si(2)O(4)N(2) is constructed by isolated and highly corrugated 12 rings which are composed of 12 vertex-sharing [SiO(2)N(2)] tetrahedra with bridging N and terminal O to form three-dimensional tunnels to accommodate the Sr(2+) ions. The calculated band structure shows that Sr(3)Si(2)O(4)N(2) is an indirect semiconductor with a band gap ≈ 2.84 eV, which is close to the experimental value ≈ 2.71 eV from linear extrapolation of the diffuse reflection spectrum. Sr(3-x)Si(2)O(4)N(2):xEu(2+) shows a typical emission band peaking at ~600 nm under 460 nm excitation, which perfectly matches the emission of blue InGaN light-emitting diodes. For Ce(3+)/Li(+)-codoped Sr(3)Si(2)O(4)N(2), one excitation band is in the UV range (280-350 nm) and the other in the UV blue range (380-420 nm), which matches emission of near-UV light-emitting diodes. Emission of Sr(3-2x)Si(2)O(4)N(2):xCe(3+),xLi(+) shows a asymmetric broad band peaking at ~520 nm. The long-wavelength excitation and emission of Eu(2+) and Ce(3+)/Li(+)-doped Sr(3)Si(2)O(4)N(2) make them attractive for applications in phosphor-converted white light-emitting diodes.

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