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1.
Inorg Chem ; 63(1): 554-563, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38151237

RESUMO

The meaningful and rational engineering of porphyrin-based catalysts with multimetallic active sites is very attractive toward photocatalytic hydrogen generation from water decomposition. Herein, three metal organic frameworks (MOFs) based on meso-tetrakis(4-carboxylphenyl)porphyrin (TCPP) were successfully constructed under solvothermal conditions. As a novel architectured photocatalyst (triclinic, C48H29N4O10PdYb), Pd/Yb-PMOF manifested diverse metal active sites, suitable bandgap positions, prominent visible light-collecting capacity, excellent carrier transfer efficiency, and obvious synergistic effect between ytterbium and palladium ions. Consequently, such a bimetallic MOF exhibited strengthened photocatalytic hydrogen evolution performance. Concretely, its hydrogen generation efficiency was up to 3196.42 µmol g-1 h-1 with 2 wt % Pt as a cocatalyst under visible light illumination. Our work demonstrates a promising strategy for highly efficient visible-light catalysts based on bimetallic-trimmed porphyrin MOFs.

2.
Drug Dev Ind Pharm ; 49(10): 617-627, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37725481

RESUMO

OBJECTIVE: To synthesis a novel 'Pharmaceutical Cocrystal' of berberine (BBR) with coformer 3-methylcinnamic acid (3MCA) for increasing its solubility and intestinal absorption property. SIGNIFICANCE: BBR-HCl has poor liposolubility, difficulty in penetrating the cell membrane and absorption in the gastrointestinal tract, low bioavailability, and limited clinical application. A new cocrystal is formed by the interaction between 3-MCA and BBR through molecular interaction, which improves the physicochemical properties, intestinal absorption property, and hygroscopicity. METHODS: The solvent evaporation method was used to synthesize BCR-3MCA cocrystal. The physicochemical properties of the crystals were confirmed by different spectral techniques, i.e. by X-ray diffraction (PXRD, SXRD), thermogravimetry and differential thermal analysis (DSC, TGA), and scanning electron microscopy (SEM). Hygroscopicity of the cocrystal was evaluated by dynamic water vapor sorption (DVS). The intestinal absorption property was evaluated by the Ussing chamber system. RESULTS: BBR and 3MCA can be directly self-assembled into uniform co-crystal by hydrogen bonds and π-π stacking interactions. Compared with BBR-HCl, the solubility of BBR-3MCA cocrystal in polar solvents of water, methanol, ethanol, and isopropanol increased by 13.9, 1.5, 4.7, and 15.8 times, respectively. The apparent absorption and the absorption rate constants were increased by 7.7 and 5.6 times, respectively. Surprisingly, BBR-3MCA co-crystal almost had no hygroscopicity. CONCLUSION: The absolute molecular structure of the co-crystal was further confirmed by single crystal X-ray diffraction. The hydrogen bonds drove the formation of X-like one-dimensional unit. Compared to the BBR-HCl, BBR-3MCA cocrystal displayed superior dissolution and solubility performance, improved physical-chemical properties and significantly improved intestinal absorption.


Assuntos
Berberina , Berberina/química , Fenômenos Químicos , Solubilidade , Cristalografia por Raios X , Absorção Intestinal
3.
World J Surg Oncol ; 12: 289, 2014 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-25241216

RESUMO

BACKGROUND: The effect of breast cancer subtype on margin status after lumpectomy remains unclear. This study aims to determine whether approximated breast cancer subtype is associated with positive margins after lumpectomy, which could be used to determine if there is an increased risk of developing local recurrence (LR) following breast-conserving surgery. METHODS: We studied 1,032 consecutive patients with invasive cancer who received lumpectomies and cavity margin (CM) assessments from January 2003 to November 2012. The following data were collected: patient age, cT stage, pT stage, grade, status of CM, lymph node status, menopausal status, ER, PR, HER-2, and Ki67, as well as the presence of extensive intraductal component (EIC) and lymphovascular invasion (LVI). A χ2 test was used to compare categorical baseline characteristics. Univariate and multivariate logistic regression analyses were performed to evaluate associations between pathologic features of CM status. Kaplan-Meier actuarial cumulative rates of LR (ipsilateral in-breast) were calculated. RESULTS: A total of 7,884 pieces of marginal tissue were collected from 1,032 patients, and 209 patients had positive CMs. Of the patients tested, 52.3% had luminal A subtype, 14.9% were luminal B, 12.8% were luminal-HER-2, 8.1% were HER-2 enriched, and 11.8% were triple negative. Univariate analysis showed that EIC (P < 0.001), LVI (P = 0.026), pN stage (N1 vs. N0: P = 0.018; N3 vs. N0: P < 0.001), and luminal B (P = 0.001) and HER-2 (P < 0.001) subtypes were associated with positive CMs. Multivariable analysis indicated that only EIC (P < 0.001), pN stage (P = 0.003), and HER-2 subtype (P < 0.001) were significantly correlated with positive CMs. On multivariable analysis, HER-2 subtype was an independent prognostic factor in LR (P = 0.031). CONCLUSIONS: The HER-2 subtype was the predictive factor most associated with positive CMs and an independent prognostic factor for LR. This result suggests that the increased risk of LR in HER-2 breast cancer is due to an increased microscopic invasive tumor burden, which is indicated by margin status after lumpectomy.


Assuntos
Neoplasias da Mama/cirurgia , Mastectomia Segmentar/efeitos adversos , Recidiva Local de Neoplasia/diagnóstico , Neoplasia Residual/diagnóstico , Complicações Pós-Operatórias/etiologia , Receptor ErbB-2/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Intraductal não Infiltrante/metabolismo , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/cirurgia , Carcinoma Lobular/metabolismo , Carcinoma Lobular/patologia , Carcinoma Lobular/cirurgia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Recidiva Local de Neoplasia/metabolismo , Estadiamento de Neoplasias , Neoplasia Residual/metabolismo , Prognóstico , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estudos Retrospectivos , Carga Tumoral , Adulto Jovem
4.
ACS Appl Mater Interfaces ; 15(3): 4845-4856, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36629327

RESUMO

Selective reduction of nitroaromatics to the corresponding amines generally requires complex conditions, involving pressurized hydrogen, higher temperatures, or organic acids. In this work, we successfully prepared a series of porphyrin-based MOF photocatalysts (Pd-PMOFs, In-PMOFs, and In/Pd-PMOFs) via a facile solvothermal method for the efficient selective reduction of nitroaromatics to corresponding anilines with deionized water as the hydrogen donor. Being a new structured material (monoclinic, C52H40InN6O8Pd), on account of the abundant pore channels, strong light absorption capability, well-matched bandgap, as well as the coordination of indium ions and palladium ions, In/Pd-MOFs have excellent migration efficiency of photo-induced electrons and holes. Specifically, the In/Pd-PMOF photocatalyst manifested superior conversion (100%) and selectivity (≥80%) toward the screened nitro compounds under mild conditions. This work avoids the use of strong reductants, organic acids, and pressurized hydrogen gas as hydrogen sources, providing a promising concept for developing green catalytic systems.

5.
Org Lett ; 25(19): 3369-3374, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37144912

RESUMO

An intermolecular direct α-C-H acylation of alkenes was revealed by the visible-light-mediated N-heterocyclic carbene and quinuclidine catalysis. This convenient protocol provides a facile synthesis toward novel natural products and drug derivatives of α-substituted vinyl ketones. Mechanistic investigations indicated that the transformation proceeded via sequential radical addition, radical coupling, and an elimination process.

6.
Breast Cancer Res Treat ; 127(3): 705-12, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21445574

RESUMO

Over the past four decades, chemotherapy has played an important role in prolonging survival in breast cancer patients. However, it may also result in undesirable side effects such as hepatitis B virus (HBV) reactivation seen in this study. With the increasing use of chemotherapy paralleling the rise in breast cancer incidence, the occurrence of HBV reactivation is likely to further increase. Several strategies use lamivudine to deal with this problem. Initially, lamivudine had been used to treat patients who developed alanine transaminase elevation attributable to HBV reactivation during chemotherapy. However, using this strategy, fatal reactivation has also been reported. Later studies have suggested that prophylactic lamivudine significantly reduces HBV reactivation and its associated morbidity. However, these studies were based mainly on patients with lymphoma, whereas studies on breast cancer patients were few. Moreover, these studies were retrospective. Recently, a prospective study has recommended that deferred preemptive lamivudine could be a comparable alternative to the prophylactic strategy. However, it was not a randomized controlled study. In this study, it was examined the efficacy of the prophylactic strategy in hepatitis B s-antigen seropositive breast cancer patients during chemotherapy using a prospective, randomized controlled study. Two groups were studied. One group consisted of 21 patients who were treated with prophylactic lamivudine, the other group consisted of 21 patients who were not treated with prophylactic lamivudine. The results showed that the prophylactic lamivudine strategy significantly decreased the incidence of HBV reactivation (0 vs. 28.6%, P = 0.021). It was conclude that the prophylactic lamivudine strategy significantly reduces the incidence of HBV reactivation for hepatitis B s-antigen seropositive breast cancer undergoing chemotherapy.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/tratamento farmacológico , Hepatite B/virologia , Lamivudina/uso terapêutico , Ativação Viral/efeitos dos fármacos , Adulto , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antivirais/uso terapêutico , Feminino , Antígenos de Hepatite/sangue , Hepatite B/prevenção & controle , Vírus da Hepatite B/fisiologia , Humanos , Lamivudina/administração & dosagem , Testes de Função Hepática , Pessoa de Meia-Idade , Estudos Prospectivos , Prevenção Secundária , Resultado do Tratamento
7.
Front Oncol ; 10: 564796, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33194642

RESUMO

Non-small cell lung cancer (NSCLC) is the predominant subtype of lung cancers. KRAS mutation is the second most prevalent mutation in NSCLC. KRAS mutant cancer cells suppress the anti-tumor T cell response. However, the underlying mechanism is still unknown. Here, we analyzed the differential expression of acetyl-CoA acyltransferase 1 (ACAA1) in various types of cancers using the TIMER database and validated the results in the NSCLC cell line H1944. We silenced oncogenic KRAS by siRNA targeting KRASG13D, and employed an MAPK signaling pathway inhibitor to clarify the possible regulatory pathway. Moreover, we analyzed the correlation of ACAA1 expression level with B cells, CD4+ T cells, CD8+ T cells, neutrophils, macrophages, and dendritic cells. Correlations between expression of ACAA1 and several biomarkers of mutation burden were also tested. Finally, we evaluated the prognostic value of ACAA1 in a wide range of cancers using the Kaplan-Meier Plotter Database. We found lower expression of ACAA1 in tumor tissue than in adjacent normal tissue in various cancers. This result was confirmed using a GEO dataset. Knock-down of mutant KRAS resulted in increased ACAA1 mRNA level in H1944 cells. ACAA1 mRNA level was significantly upregulated in H1944 after treatment with MAPK pathway inhibitor sorafenib, indicating that oncogenic KRAS may downregulate ACAA1 through MAPK signaling. ACAA1 was negatively correlated with biomarkers of tumor mutation burden, including BRCA1, ATM, ATR, CDK1, PMS2, MSH2, and MDH6. Conversely, ACAA1 expression was positively correlated with infiltrating CD4+ cells and with Th1, Th2, Treg cells in the lung tumor microenvironment. Finally, we showed that ACAA1 is a predictive factor for survival in several cancer types. In summary, decreased ACAA1 expression is correlated with poor prognosis and decreases immune infiltration of CD4+ T cells in LUAD and LUSC. ACAA1 also predicts T cell exhaustion in LUSC. The mechanism underlying KRAS/ACAA1 axis-mediated regulation of immune cell infiltration requires further investigation.

8.
Cell Mol Gastroenterol Hepatol ; 10(4): 811-828, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32615164

RESUMO

BACKGROUND & AIMS: Gemcitabine resistance is rapidly acquired by pancreatic ductal adenocarcinoma (PDAC) patients. Novel approaches that predict the gemcitabine response of patients and enhance gemcitabine chemosensitivity are important to improve patient survival. We aimed to identify genes as novel biomarkers to predict the gemcitabine response and the therapeutic targets to attenuate chemoresistance in PDAC cells. METHODS: Genome-wide RNA interference screening was conducted to identify genes that regulated gemcitabine chemoresistance. A cell proliferation assay and a tumor formation assay were conducted to study the role of lethal giant larvae homolog 1 (LLGL1) in gemcitabine chemoresistance. Levels of LLGL1 and its regulating targets were measured by immunohistochemical staining in tumor tissues obtained from patients who received gemcitabine as a single therapeutic agent. A gene-expression microarray was conducted to identify the targets regulated by LLGL1. RESULTS: Silencing of LLGL1 markedly reduced the gemcitabine chemosensitivity in PDAC cells. Patients had significantly shorter survival (6 months) if they bore tumors expressing low LLGL1 level than tumors with high LLGL1 level (20 months) (hazard ratio, 0.1567; 95% CI, 0.05966-0.4117). Loss of LLGL1 promoted cytokine receptor oncostatin M receptor (OSMR) expression in PDAC cells that led to gemcitabine resistance, while knockdown of OSMR effectively rescued the chemoresistance phenotype. The LLGL1-OSMR regulatory pathway showed great clinical importance because low LLGL1 and high OSMR expressions were observed frequently in PDAC tissues. Silencing of LLGL1 induced phosphorylation of extracellular signal-regulated kinase 2 and specificity protein 1 (Sp1), promoted Sp1 (pThr453) binding at the OSMR promoter, and enhanced OSMR transcription. CONCLUSIONS: LLGL1 possessed a tumor-suppressor role as an inhibitor of chemoresistance by regulating OSMR-extracellular signal-regulated kinase 2/Sp1 signaling. The data sets generated and analyzed during the current study are available in the Gene Expression Omnibus repository (ID: GSE64681).


Assuntos
Carcinoma Ductal Pancreático/tratamento farmacológico , Proteínas do Citoesqueleto/genética , Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pancreáticas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/genética , Linhagem Celular Tumoral , Desoxicitidina/uso terapêutico , MAP Quinases Reguladas por Sinal Extracelular/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Subunidade beta de Receptor de Oncostatina M/genética , Neoplasias Pancreáticas/genética , Fator de Transcrição Sp1/genética , Transcriptoma , Adulto Jovem , Gencitabina , Neoplasias Pancreáticas
9.
Org Lett ; 20(8): 2477-2480, 2018 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-29613809

RESUMO

A novel approach for the synthesis of indolizines from 2-(pyridin-2-yl)acetates, ynals, and alcohols or thiols has been developed. This MCR (multicomponent reaction) that proceeds under the solvent- and metal-free conditions has provided a straightforward path to construct indolizines. Furthermore, this reaction demonstrates other attractive features such as widely available starting materials, mild conditions, good functional group tolerance, and high efficiency.

10.
World J Gastroenterol ; 22(33): 7463-77, 2016 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-27672269

RESUMO

The role of bile acids in colorectal cancer has been well documented, but their role in pancreatic cancer remains unclear. In this review, we examined the risk factors of pancreatic cancer. We found that bile acids are associated with most of these factors. Alcohol intake, smoking, and a high-fat diet all lead to high secretion of bile acids, and bile acid metabolic dysfunction is a causal factor of gallstones. An increase in secretion of bile acids, in addition to a long common channel, may result in bile acid reflux into the pancreatic duct and to the epithelial cells or acinar cells, from which pancreatic adenocarcinoma is derived. The final pathophysiological process is pancreatitis, which promotes dedifferentiation of acinar cells into progenitor duct-like cells. Interestingly, bile acids act as regulatory molecules in metabolism, affecting adipose tissue distribution, insulin sensitivity and triglyceride metabolism. As a result, bile acids are associated with three risk factors of pancreatic cancer: obesity, diabetes and hypertriglyceridemia. In the second part of this review, we summarize several studies showing that bile acids act as cancer promoters in gastrointestinal cancer. However, more question are raised than have been solved, and further oncological and physiological experiments are needed to confirm the role of bile acids in pancreatic cancer carcinogenesis.


Assuntos
Ácidos e Sais Biliares/metabolismo , Carcinogênese , Neoplasias Pancreáticas/metabolismo , Adenocarcinoma/etiologia , Adenocarcinoma/metabolismo , Consumo de Bebidas Alcoólicas , Complicações do Diabetes/patologia , Dieta , Humanos , Hipertrigliceridemia/complicações , Resistência à Insulina , Síndrome Metabólica/complicações , Síndrome Metabólica/metabolismo , Obesidade/complicações , Pâncreas/metabolismo , Neoplasias Pancreáticas/etiologia , Pancreatite , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Risco , Transdução de Sinais , Fumar
11.
Asian Pac J Cancer Prev ; 15(1): 315-20, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24528048

RESUMO

PURPOSE: The purpose of this study was to investigate the recurrence pattern and characteristics of patients based on the 2013 St. Gallen surrogate molecular subtypes after breast-conserving surgery (BCS) in Chinese women. METHODS: This retrospective analysis included 709 consecutive breast cancer patients undergoing BCS from 1999-2010 at our institution. Five different surrogate subtypes were created using combined expression of the estrogen receptor, progesterone receptor, and human epidermal growth factor receptor-2. Locoregional relapse-free survival (LRRFS), distant metastasis-free survival (DMFS), and disease-free survival (DFS) rates were calculated. RESULTS: The 5-year LRRFS, DMFS, and DFS rates were 90.5%, 88.2%, and 81.5%, respectively. Multivariate analysis revealed that young age, node-positive disease, and HER2 enrichment were independent prognostic factors in LRRFS patients. There was also an independent prognostic role of lymph node-positive disease in DMFS and DFS patients. Patients with luminal A tumors had the most favorable prognosis, with LRRFS, DMFS, and DFS rates of 93.2%, 91.5%, and 87.5% at 5 years, respectively. Conversely, HER-2-enriched tumors exhibited the highest rate of recurrence (27.5%) and locoregional recurrence (11.4%). CONCLUSION: Surrogate subtypes present with significant differences in RFS, DMFS, and LRRFS. Luminal A tumors have the best prognosis, whereas HER2-enriched tumors have the poorest.


Assuntos
Neoplasias da Mama/química , Neoplasias da Mama/patologia , Recidiva Local de Neoplasia/química , Receptor ErbB-2/análise , Adulto , Fatores Etários , Neoplasias da Mama/cirurgia , China , Intervalo Livre de Doença , Feminino , Humanos , Metástase Linfática , Mastectomia Segmentar , Gradação de Tumores , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Estudos Retrospectivos , Taxa de Sobrevida
12.
J Cancer Res Clin Oncol ; 140(4): 599-605, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24509653

RESUMO

PURPOSE: Atypical hyperplasia (AH) is associated with a relatively higher risk of subsequent development of cancer. It remains controversial whether it is necessary to re-excise AH found at surgical margins during breast-conserving surgery (BCS). The aim of this study was to determine the impact of atypical ductal/lobular hyperplasia found at the margins during BCS on the prognosis of early-stage breast cancer patients. METHODS: A retrospective analysis comparing patients with AH and receiving no further surgical treatment (n = 233) to those without AH at the margins during BCS (n = 158) was performed. RESULTS: At a median follow-up of 76 months, the 5- and 8-year rates of ipsilateral breast tumor recurrence (IBTR) were 3.26 and 8.79% for women with AH and 2.56 and 8.95% for women without AH, respectively. There were no significant differences between the two groups in terms of IBTR (p = 0.803), distant-metastasis-free survival (DMFS) (p = 0.749), or overall survival (OS) (p = 0.165). Moreover, no significant differences were found in IBTR, DMFS, or OS between patients with severe atypical hyperplasia (n = 86) and those without AH (n = 158) (p = 0.81, 0.82, and 0.78, respectively). Additionally, young women or those with ductal carcinoma in situ or triple-negative breast cancer with AH involving margins did not have a higher IBTR rate when compared to similar patients without AH. CONCLUSIONS: This study suggests that AH found at the margins during BCS does not increase the risk of subsequently developing an IBTR. There is not enough evidence for re-excision of AH found at the margins during BCS in patients with early-stage breast cancer.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Lobular/patologia , Hiperplasia/patologia , Mastectomia Segmentar/efeitos adversos , Recidiva Local de Neoplasia/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Intraductal não Infiltrante/cirurgia , Carcinoma Lobular/cirurgia , Feminino , Seguimentos , Humanos , Hiperplasia/cirurgia , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/diagnóstico , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
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