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1.
Food Chem ; 460(Pt 1): 140529, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39047468

RESUMO

In this work, a novel fluorinated magnetic microporous organic network (Fe3O4@FMON) was exquisitely designed and synthesized for highly efficient and selective magnetic solid phase extraction (MSPE) of fluorinated benzoylurea insecticides (BUs) from complex tea beverage samples. The Fe3O4@FMON exhibited good extraction for BUs via the pre-designed hydrophobic, π-π stacking, hydrogen bonding and specific FF interactions. A sensitive Fe3O4@FMON-based MSPE-HPLC-UV method with wide linear range (0.10-1000 µg L-1, R2 ≥ 0.996), low limits of detection (0.01-0.02 µg L-1), and large enrichment factors (85.6-98.0) for BUs from tea beverage samples was developed. By decorating F elements within MON's networks, the Fe3O4@FMON characterized good hydrophobicity and chemical stability, which could be reused at least 8 times without decrease of recoveries. This work demonstrated the great prospects of Fe3O4@FMON for enriching trace BUs from complex substrates and triggered the potential of FMON for sample pretreatment of fluorinated analytes.

2.
Talanta ; 257: 124391, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36854206

RESUMO

Microporous organic networks (MONs) are promising materials for the magnetic solid-phase extraction (MSPE) of trace targets from diverse complex samples. However, all the reported magnetic MONs (MMONs) are mono-functionalized and synthesized by refluxing at high temperatures, which is not an energy-efficient and environmentally friendly method. Here, for the first time, we report the room-temperature fabrication of a novel dual-functionalized MMON (MMON-B) for the efficient MSPE of typical vanillin additives from food samples prior to high-performance liquid chromatography (HPLC). The conjugated MMON-B with numerous -OH and -NH2 groups afforded good extraction for vanillins via π-π, hydrophobic, and hydrogen-bonding interactions. The factors affecting the extraction were studied in detail. Under the optimal conditions, the developed MMON-B-MSPE-HPLC-UV method exhibited wide linear range (0.50-1200 µg L-1), low limits of detection (0.10-0.15 µg L-1), and good reusability and stability. Therefore, MMON-B was successfully used to enrich vanillins in complex food samples. The morphology and extraction efficiency of the room-temperature synthesized MMON-B were comparable with those of the MMON-B synthesized via the conventional reflux method, indicating that the room-temperature fabrication method is a good alternative to the reflux method. This study presents the feasibility of using a room-temperature method for synthesizing dual-functionalized MONs, and the findings may significantly promote the application of MONs in the MSPE of trace targets from complex matrices.


Assuntos
Alimentos , Magnetismo , Temperatura , Fenômenos Magnéticos , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Limite de Detecção
3.
ACS Appl Mater Interfaces ; 15(30): 36822-36830, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37467423

RESUMO

Despite the rapid development of versatile metal-organic frameworks (MOFs), the synthesis of water-stable MOFs remains challenging, which significantly limits their practical applications. Herein, a novel engineering strategy was developed to prepare superhydrophobic MOFs by an in situ fluorinated microporous organic network (FMON) coating. Through controllable modification, the resulting MOF@FMON retained the porosity and crystallinity of the pristine MOFs. Owing to the superhydrophobicity of the FMON and the feasibility of MOF synthesis, the FMON coating could be in situ integrated with various water-sensitive MOFs to provide superhydrophobicity. The coating thickness and hydrophobicity of the MOF@FMON composites were easily regulated by changing the FMON monomer concentration. The MOF@FMON composites exhibited excellent oil/water separation and catalytic activities and enhanced durability in aqueous solutions. This study provides a general approach for the synthesis of superhydrophobic MOFs, expanding the application scope of MOFs.

4.
J Agric Food Chem ; 71(16): 6277-6287, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37068196

RESUMO

In moths, the interactions between chemosensory proteins (CSPs) and sex pheromones have yet to be comprehensively investigated. Here, we examined the function of AlepCSP2 in male Athetis lepigone based on protein expression, molecular docking, site-directed mutagenesis, fluorescence competitive binding analyses, and RNA interference (RNAi) experiments. We found that AlepCSP2 showed strong binding affinity for two sex pheromones and five maize volatiles and that binding was optimal under neutral conditions. Furthermore, we identified six amino acids as being key residues involved in the interaction between AlepCSP2 and multiple ligands. Further RNAi showed that siCSP2 males displayed consistently lower electroantennography responses to two sex pheromones and three maize volatiles at different dosages tested, and the mating rate also decreased significantly by 37.50%. These findings will contribute to characterizing the binding mechanisms of moth CSPs to sex pheromones and host volatiles and also identify unique targets for developing novel pest behavior disruptors.


Assuntos
Mariposas , Atrativos Sexuais , Masculino , Animais , Atrativos Sexuais/metabolismo , Zea mays/genética , Zea mays/metabolismo , Simulação de Acoplamento Molecular , Mariposas/metabolismo , Proteínas de Insetos/metabolismo , Percepção , Feromônios/metabolismo
5.
Int J Colorectal Dis ; 25(5): 583-90, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20195621

RESUMO

BACKGROUNDS AND AIMS: Lgr5 is a member of the G protein receptor super-family and was shown recently to be a stem cell marker for cells with intestinal differentiation. Its over-expression has been demonstrated in hepatocellular, basal cell carcinoma, and ovarian cancers but the underlying mechanisms are poorly understood. The aim of this study was to investigate if Lgr5 over-expression was correlated with human colorectal carcinogenesis and its potential correlation with beta-catenin. METHODS: The study was carried out on a tissue microarray that consisted of 102 colorectal carcinomas (CRC; M:F = 55:47), 18 colon adenoma, and 12 colon normal mucosa cases. Immunostains were performed with the standard EnVision method with primary antibodies against Lgr5, beta-catenin, and p53 antigens. Immunoreactivity of neoplastic cells to each antibody was double-blindly semi-quantified by two pathologists and the data were analyzed with the Chi-square and Spearman rank correlation tests. Subsequently, expression of Lgr5 in tissue sections of tumor centre and invasive margins of 21 cases of CRC certified to be immunoreactive of Lgr5 in TMA were evaluated and possible differences of Lgr5 expression between them were analyzed. RESULTS: Lgr5 immunoreactivity was observed only in single cells in the base of normal colon mucosal crypts but high in 28% (five out of 18) adenomas, and significantly higher in 54% (55/102, p = 0.016) CRC cases. In normal mucosa, adenoma, and CRC, beta-catenin expression was seen in 25% (three out of 12), 27% (five out of 18), and 81% (83/102) cases, respectively, in contrast to 0, 0, and 40% (41/102) for p53 expression, respectively. In CRC, Lgr5 expression was more intense in women than men (p < 0.0001), and positively correlated with beta-catenin expression (p < 0.001), but not with patients' ages, tumor sizes, nodal status, TNM stages, and p53 expression. Different expression of Lgr5 between tumor centre and invasive margins was not found (p > 0.05). CONCLUSIONS: The results suggest that up-regulation of Lgr5 expression, especially in female patients, may play an important role in colorectal carcinogenesis, probably through the WNT/beta-catenin pathway, but not involve the progression of the CRC.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Receptores Acoplados a Proteínas G/metabolismo , beta Catenina/metabolismo , Adenoma/metabolismo , Adenoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Proteína Supressora de Tumor p53/metabolismo
6.
Zhonghua Bing Li Xue Za Zhi ; 38(1): 23-8, 2009 Jan.
Artigo em Zh | MEDLINE | ID: mdl-19489221

RESUMO

OBJECTIVES: Basal cell-like breast cancer is one of the subtypes using molecular typing, and this subtype attracted a wide spread attention. Currently, no uniform diagnostic criteria are available. Most studies demonstrated poor outcomes, but contradictory conclusions appeared recently. The prognosis of basal cell-like breast cancer using different immunohistochemical criteria were analyzed. METHODS: Two hundred and eighty-four invasive breast cancers with a follow-up information over 5 years were evaluated for ER, PR, HER2, CK5/6, CK14, EGFR expression on tissue microarray immunohistochemically. Based on the results, these cases using four different diagnostic criteria were categorized, namely: Nielsen (ER-/HER2-, CK5/6+ and/or EGFR+), Kim (ER-/PR-/HER2-, CK5/6+ and/or CK14+ and/or EGFR+), Triple-negative (ER-/PR-/HER2-), and basal-CK (CK5/6+ and/or CK14+). 5-year survival information was compared between groups. RESULTS: The prevalence of basal cell-like breast cancer by Nielsen, Kim, Triple-negative and basal-CK were 15.5% (44/284), 14.8% (42/284), 43.3% (123/284) and 21.1% (60/284) respectively; the recurrence rates were 18.2% (8/44), 21.4% (9/42), 10.6% (13/123) and 11.7% (7/60) respectively. These were higher than recurrence rates for other subtypes, but only the differences by Nielsen's and Kim's criteria were significant. Using Nielsen's and Triple-negative's criteria, basal-like tumors showed shorter 5-year disease-free survival (both P < 0. 01) and overall survival (P < 0.05 and 0.01) than luminal A subtype, using Kim's criteria, basal-like tumors showed a lower 5-year disease-free but not overall survival than luminal A subtype (P < 0.01); no significant difference was found on 5-year survival between basal-like and non-basal-like tumors when typed by basal-CK. CONCLUSION: Basal cell-like breast cancers are more likely to show more recurrence and worse outcome, but different immunohistochemical diagnostic criteria have an influence on their prognostic analysis, so a uniform diagnostic criteria is essential for the further study of basal-like breast cancers.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Neoplasia de Células Basais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/secundário , Neoplasias da Mama/classificação , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/secundário , Intervalo Livre de Doença , Receptores ErbB/metabolismo , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Queratina-5/metabolismo , Queratina-6/metabolismo , Neoplasias Pulmonares/secundário , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neoplasia de Células Basais/metabolismo , Neoplasia de Células Basais/secundário , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Taxa de Sobrevida , Adulto Jovem
8.
Int J Mol Med ; 39(2): 430-436, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28035366

RESUMO

Oxidative stress in the rostral ventrolateral medulla (RVLM) plays an important role in the pathophysiology of hypertension. Alpha­lipoic acid (ALA) is widely recognized for its potent superoxide inhibitory properties, and it can safely penetrate deep into the brain. The aim of this study was to explore whether ALA supplementation attenuates hypertensive responses and cardiac hypertrophy by decreasing the NAD(P)H oxidase (NOX)-derived overproduction of reactive oxygen species (ROS) in the mitochondria in the RVLM, and thus attenuating the development of salt­induced hypertension. For this purpose, male Wistar rats were randomly divided into 2 groups and either fed a high-salt diet or not. After 8 weeks, the rats were either administered ALA or an equal volume of the vehicle for 8 weeks. The rats fed a high­salt diet exhibited higher mean arterial pressure (MAP) and higher plasma noradrenaline (NE) levels, as well as cardiac hypertrophy, as evidence by the increased whole heart weight/body weight (WHW/BW) ratio, WHW/tibia length (TL) ratio and left­ventricular weight (LVW)/TL ratio. Compared with the rats in the NS group, the rats in the HS group only exhibited increased levels of superoxide, NOX2, NOX4 and mitochondrial malondialdehyde (MDA), but also decreased levels of copper/zinc (Cu/Zn)-superoxide dismutase (SOD), mitochondrial SOD and glutathione (GSH) in the RVLM. The supplementation of ALA decreased MAP, plasma NE levels and the levels of cardiac hypertrophy indicators. It also decreased the levels of superoxide, NOX2, NOX4 and mitochondrial MDA, and increased the levels of Cu/Zn­SOD, mitochondrial SOD and GSH in the RVLM compared with the rats fed a high-salt diet and not treated with ALA. On the whole, our findings indicate that long­term ALA supplementation attenuates hypertensive responses and cardiac hypertrophy by decreasing the expression of NAD(P)H subunits (NOX2 and NOX4), increasing the levels of mitochondrial bioenergetic enzymes, and enhancing the intracellular antioxidant capacity in the RVLM during the development of hypertension.


Assuntos
Antioxidantes/farmacologia , Hipertensão/etiologia , Hipertensão/metabolismo , Bulbo/efeitos dos fármacos , Bulbo/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Sais/efeitos adversos , Ácido Tióctico/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Dieta , Modelos Animais de Doenças , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Biológicos , NADPH Oxidases/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo
9.
Mol Med Rep ; 11(1): 734-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25338527

RESUMO

Glioblastoma is the most common type of malignant brain tumor with a poor prognosis. The Notch signaling pathway is often aberrantly activated in glioma cells. In order to determine the expression of Notch 2 and to evaluate its possible prognostic value in malignant glioblastoma, specimens from 32 patients and 20 controls were analyzed using immunohistochemical staining and reverse transcription quantitative polymerase chain reaction. The expression of Notch 2 in the glioma tissues was significantly higher compared with that in the normal brain tissues (P<0.01). Subsequently, endogenous Notch 2 interference was effectively performed by specific small hairpin (sh)RNA in the glioma cancer cell line U251. The results from an MTT assay and from Annexin V-fluorescein isothiocyanate/propidium iodide staining indicated that interference of Notch 2 significantly inhibited the proliferation and induced the apoptosis of U251 cells. In addition, the cell cycle was analyzed using flow cytometry and the results revealed that Notch 2 shRNA induced cell cycle arrest at the G0/G1 phase in U251 cells. Additionally, proteins associated with the cell cycle and cell proliferation were detected using western blot analysis. The data demonstrated that the expression of P21, cyclin D and phosphorylated retinoblastoma was significantly inhibited in the Notch 2 shRNA-transfected U251 cells. The results of the present study provide further insights into the effects of Notch 2 and a molecular reference for brain tumor therapy.


Assuntos
Apoptose/genética , Ciclo Celular/genética , Glioma/genética , Glioma/patologia , Interferência de RNA , Receptor Notch2/genética , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Glioma/metabolismo , Humanos , RNA Interferente Pequeno/genética , Receptor Notch2/metabolismo
10.
J Dig Dis ; 15(7): 359-66, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24720626

RESUMO

OBJECTIVE: Guided by the recently established histological criteria of the gastroesophageal junction (GEJ), we aimed to investigate and compare trends in the proportions of small (≤ 2 cm) proximal gastric carcinoma (PGC) vs non-PGC (NPGC) in Chinese patients over an 8-year period. METHODS: The study was conducted with consecutive surgical resected specimens of small PGC that was located within 3 cm below the GEJ and NPGC (located at all other gastric regions) treated at a single medical center in China. Differences in proportions between the two groups were compared. RESULTS: Among all 313 cases, 111 (35.5%) were classified as PGC and the remaining 202 (64.5%) as NPGC. Patients with PGC were significantly elder than those with NPGC, and none aged younger than 40 years. The proportions of PGC significantly and progressively increased from 16% in 2004 to 45% in 2011, in contrast to a steady decreasing trend for NPGC from 84% to 55% over the same period. The difference in trends between the two groups approached, but was not at a statistically significant level (P = 0.08). Proportions of small cancers in the gastric corpus and in female patients remained low and stable, in contrast to a significantly higher proportion in male patients (P < 0.05). CONCLUSIONS: Our data showed a significantly upward-shifting trend in the proportions of small PGC, primarily in elderly male patients, in contrast to a downward shifting trend in NPGC over the most recent 8-year period in Chinese patients.


Assuntos
Adenocarcinoma/patologia , Neoplasias Gástricas/patologia , Adenocarcinoma/epidemiologia , Adenocarcinoma/cirurgia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Junção Esofagogástrica , Feminino , Gastrectomia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Neoplasias Gástricas/epidemiologia
11.
World J Gastroenterol ; 18(27): 3602-9, 2012 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-22826627

RESUMO

AIM: To investigate the clinicopathologic features which predict surgical overall survival in patients with proximal gastric carcinoma involving the esophagus (PGCE). METHODS: Electronic pathology database established in the Department of Pathology of the Nanjing Drum Tower Hospital was searched for consecutive resection cases of proximal gastric carcinoma over the period from May 2004 through July 2009. Each retrieved pathology report was reviewed and the cases with tumors crossing the gastroesophageal junction line were selected as PGCE. Each tumor was re-staged, following the guidelines on esophageal adenocarcinoma, according to the 7th edition of the American Joint Commission on Cancer Staging Manual. All histology slides were studied along with the pathology report for a retrospective analysis of 13 clinicopathologic features, i.e., age, gender, Helicobacter pylori (H. pylori) infection, surgical modality, Siewert type, tumor Bormann's type, size, differentiation, histology type, surgical margin, lymphovascular and perineural invasion, and pathologic stage in relation to survival after surgical resection. Prognostic factors for overall survival were assessed with uni- and multi-variate analyses. RESULTS: Patients' mean age was 65 years (range: 47-90 years). The male: female ratio was 3.3. The 1-, 3- and 5-year overall survival rates were 87%, 61% and 32%, respectively. By univariate analysis, age, male gender, H. pylori, tumor Bormann's type, size, histology type, surgical modality, positive surgical margin, lymphovascular invasion, and pT stage were not predictive for overall survival; in contrast, perineural invasion (P = 0.003), poor differentiation (P = 0.0003), > 15 total lymph nodes retrieved (P = 0.008), positive lymph nodes (P = 0.001), and distant metastasis (P = 0.005) predicted poor post-operative overall survival. Celiac axis nodal metastasis was associated with significantly worse overall survival (P = 0.007). By multivariate analysis, ≥ 16 positive nodes (P = 0.018), lymph node ratio > 0.2 (P = 0.003), and overall pathologic stage (P = 0.002) were independent predictors for poor overall survival after resection. CONCLUSION: Patients with PGCE showed worse overall survival in elderly, high nodal burden and advanced pathologic stage. This cancer may be more accurately staged as gastric, than esophageal, cancer.


Assuntos
Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/patologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Adenocarcinoma/cirurgia , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Neoplasias Esofágicas/cirurgia , Junção Esofagogástrica/cirurgia , Feminino , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Neoplasias Gástricas/cirurgia , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
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