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1.
J Thorac Dis ; 16(1): 368-378, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38410561

RESUMO

Background: Data remains limited as to whether the order of pulmonary vessel division during performance of a lobectomy for non-small cell lung cancer (NSCLC) affects survival outcomes. Some authors have suggested that ligation of the pulmonary veins should be conducted first in order to minimize the spread of tumor cells secondary to manipulation of the lung. This study examines whether there is a difference in outcomes between patients who undergo robotic lobectomies for NSCLC using a vein-first (V-first) vs. artery-first (A-first) technique. Methods: A retrospective review of electronic medical record data was performed for patients who underwent robotic lobectomies from January 2013 to May 2019. Patients were separated into two groups based on the sequence in which the pulmonary vessels were divided: V-first or A-first. Baseline characteristics and postoperative events were recorded and compared between groups using Chi-squared and Student's t-tests. Kaplan-Meier survival curves for overall and recurrence-free survival were constructed and compared with log-rank tests. Results: A total of 374 patients were identified: 94 V-first and 280 A-first patients. There was no significant difference between the V-first and A-first groups with regards to postoperative complications, length of stay, recurrence-free survival, or overall survival. Conclusions: Our study suggests that choosing a V-first vs. A-first technique for a robotic lobectomy does not significantly impact overall survival or cancer recurrence for patients with NSCLC. Further studies are needed to evaluate whether the order of pulmonary vessel resection affects outcomes for patients with NSCLC.

2.
Acta Biomater ; 96: 321-329, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31326665

RESUMO

Embryonic stem cells (ESC) are excellent cell culture systems for elucidating developmental signals that may be part of the stem cell niche. Although stem cells are traditionally induced using predominately soluble signals, the mechanical environment of the niche can also play a role in directing cells towards differential cell lineages. Interested in diverging vascular fates, we set out to examine to what extent mechanical signaling played a role in endothelial cell and/or smooth muscle fate. Using chemically-defined staged vascular differentiation methods, vascular progenitor cells (VPC) fate was examined on single stiffness polyacrylamide hydrogels of 10 kPa, 40 kPa and >0.1 GPa. Emergence of vascular cell populations aligned with corresponding hydrogel stiffness: EC-lineages favoring the softer material and SMC lineages favoring the stiffest material. Statistical significance was observed on both cell lines on almost all days. Transcriptome analysis indicated that the populations on the varying stiffness emerge in distinct categories. Lastly, blocking studies show that αvß1, and not αvß6, activation mediates stiffness-directed vascular differentiation. Overall, these studies indicate that softer materials direct VPCs into a more EC-like fate compared to stiffer materials. STATEMENT OF SIGNIFICANCE: Although stem cells are traditionally induced using predominately soluble signals, the mechanical environment of the niche also plays a role in directing cell fate. Several studies have examined the stiffness-induced cell fate from mesenchymal stem cells (MSCs) and undifferentiated embryonic stem cells (ESCs). This is the first study that rigorously examines the role of matrix stiffness in diverging vascular fates from a purified population of vascular progenitor cells (VPCs). We show that the emergence of endothelial cell (EC) versus smooth muscle cell (SMC) populations corresponds with hydrogel stiffness: EC-lineages favoring the softness material and SMC lineages favoring the stiffest material, and that αvß1 activation mediates this stiffness-directed vascular differentiation.


Assuntos
Resinas Acrílicas/química , Vasos Sanguíneos/fisiologia , Hidrogéis/química , Fenômenos Mecânicos , Resinas Acrílicas/farmacologia , Animais , Vasos Sanguíneos/efeitos dos fármacos , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Ontologia Genética , Hidrogéis/farmacologia , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/efeitos dos fármacos , Células-Tronco Embrionárias Murinas/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
3.
Bioorg Med Chem Lett ; 24(2): 495-500, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24388807

RESUMO

A series of naphthopyrans was synthesized employing silica supported fluoroboric acid under solvent free conditions in a microwave reactor. The catalytic influence of HBF4-SiO2 was investigated in detail to optimize the reaction conditions. The synthesised compounds were evaluated for in vitro xanthine oxidase inhibitory activity for the first time. Structure-activity relationship analyses have also been presented. Among the synthesised compounds, NP-17, NP-19, NP-20, NP-23, NP-24, NP-25 and NP-26 were the active inhibitors with an IC50 ranging from 4 to 17 µM. Compound NP-19 with a thiophenyl ring at position 1 emerged as the most potent xanthine oxidase inhibitor (IC50=4 µM) in comparison to allopurinol (IC50=11.10 µM) and febuxostat (IC50=0.025 µM). The basis of significant inhibition of xanthine oxidase by NP-19 was rationalized by its molecular docking at MTE binding site of xanthine oxidase.


Assuntos
Boratos/síntese química , Micro-Ondas , Naftalenos/síntese química , Piranos/síntese química , Dióxido de Silício/síntese química , Xantina Oxidase/antagonistas & inibidores , Boratos/metabolismo , Catálise , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Naftalenos/metabolismo , Piranos/metabolismo , Dióxido de Silício/metabolismo , Xantina Oxidase/metabolismo
4.
Indian J Clin Biochem ; 29(1): 69-73, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24478552

RESUMO

Dietary and lifestyle factors have been shown to have a profound effect on paraoxonase-1 (PON1) activity. Cigarette smoke has been shown to inhibit its mass and activity where as resveratrol has been shown to enhance it. We exposed hepatoma derived cell line (HepG2) to resveratrol and nicotine in varying doses and measured PON1 enzymatic activity and PON1 gene expression. In addition, total protein content of HepG2 cells was also measured. Resveratrol in a dose of 15 µmol/l or above significantly increased the PON1 enzyme activity (p > 0.001) where as nicotine in a dose of 1 µmol/l or higher significantly reduced it (p < 0.05). The resveratrol in this dose also enhanced the PON1 gene expression whereas nicotine decreased it as compared to controls. However, the protein conent of cells was not changed suggesting that they were not cytotoxic in the doses used. Till date the antioxidant vitamins have shown disappointing results against LDL oxidation and cardiovascular protection. However, the effect of resveratrol on PON1 gene expression and activity was significant, suggesting increase in PON1 activity and enhanced gene expression may be its alternative mechanism for offering protection against cardiovascular disease and may be an potential pharmacological agent which can be used for this.

5.
Med Chem ; 9(3): 402-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22920094

RESUMO

The LIM-Kinase 2 (LIMK2) inhibitory activity of a series of pyrrolopyrimidine analogs has been analyzed through combinatorial protocol in multiple linear regressions (CP-MLR) and partial least square (PLS) using different descriptors obtained from DRAGON software. The empirical, topological and charge descriptors have led to statistically significant QSAR models and showed good external predictivity as reflected in test set R2 values (0.782 to 0.888). The obtained structure-activity correlations underlined the significance of bulkiness and molecular polarizability in improving the activity. The topological descriptors suggested that open chain or branched substituents are favorable while cyclic /ring substituents are unfavorable for the activity. The descriptors identified in the study showed that pyrrolopyrimidine scaffold holds scope for modulating LIMK2 inhibitory activity. The study gives a direction for further exploration of chemical space of pyrrolopyrimidine analogs as LIMK2 inhibitors.


Assuntos
Quinases Lim/antagonistas & inibidores , Modelos Biológicos , Pirimidinas/química , Pirróis/química , Técnicas de Química Combinatória , Glaucoma/tratamento farmacológico , Análise dos Mínimos Quadrados , Modelos Lineares , Hipertensão Ocular/tratamento farmacológico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico
6.
J Enzyme Inhib Med Chem ; 28(3): 515-22, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22304474

RESUMO

The glutaminyl cyclase inhibitory activity of a series of imidazoles has been analyzed through combinatorial protocol in multiple linear regressions (CP-MLR) and partial least square using different topological and structural descriptors. The QC activity was found to be correlated with 2D-autocorrelation (2DAUTO) and atom centered fragments (ACF) descriptors. The descriptor from 2DAUTO class showed that molecular structure frames of one, six and seven path length associated with atomic van der Waals volumes and polarizability hold scope for modulating QC inhibitory activity. The ACF descriptors suggested that the unsubstituted alkyl fragments and methyl substituted imidazole ring are favorable, while unsaturation in the same and C=N-C≡N are unfavorable for activity. The molar refractivity (MR) is conducive for activity. The descriptors identified in the study collectively highlight the significance of molecular volume and polarizability to the QC inhibitory activity of imidazoles. The models are statistically significant and showed good predictivity.


Assuntos
Aminoaciltransferases/antagonistas & inibidores , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Imidazóis/química , Relação Quantitativa Estrutura-Atividade , Técnicas de Química Combinatória/métodos , Humanos , Análise dos Mínimos Quadrados , Modelos Lineares , Estrutura Molecular
7.
Med Chem ; 9(5): 642-50, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23061561

RESUMO

Tubulin is the one of the most useful and strategic molecular targets for anticancer drugs. Agents that bind in Colchicine-binding site of tubulin include Phenstatin, Combretastatin A-4, Colchicine, Steganacin, Podophyllotoxin and certain other synthetic analogues of these compounds. Arylidene pyrollo and pyrido [2,1- b] quinazolones (isoindigatone and its synthetic analogues) have been earlier reported to be tubulin inhibitors evidenced by tubulin polymerization assay. The present study is an extension of the library of the isoindigatone and its synthetic analogues to generate the structure activity relationship. The study explores the role of the arylidene ring and also provides some intresting observations such as the placement of bicyclic ring such as naphylidene for potential activity. Some of the important interactions of KNH- 3 and KNH-11 with the amino acid residues of active site of Tubulin have also been observed by molecular modeling.


Assuntos
Antineoplásicos/farmacologia , Simulação de Acoplamento Molecular , Pirazóis/farmacologia , Piridinas/farmacologia , Quinazolinonas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Células MCF-7 , Estrutura Molecular , Pirazóis/síntese química , Pirazóis/química , Piridinas/síntese química , Piridinas/química , Quinazolinonas/síntese química , Quinazolinonas/química , Relação Estrutura-Atividade
8.
Arch Pharm (Weinheim) ; 346(1): 7-16, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23076715

RESUMO

In an attempt to develop non-purine-based xanthine oxidase (XO) inhibitors, keeping in view the complications reported with the use of purine-based XO inhibitors, the flavone framework (a class possessing XO inhibitory potential) was used as lead structure for further optimization. By means of structure-based classical bioisosterism, quinolone was used as an isoster for chromone (a bicyclic unit present in flavones), owing to the bioactive potential and drug-like properties of quinolones. This type of replacement does not alter the shape and structural features required for XO inhibition, and also provides some additional interaction sites, without the loss of hydrogen bonding and hydrophobic and arene-arene interactions. In the present study, a series of 2-aryl/heteroaryl-4-quinolones (aza analogs of flavones) was rationally designed, synthesized and evaluated for in vitro XO inhibitory activity. Some notions about structure-activity relationships are presented indicating the influence of the nature of the 2-aryl ring on the inhibitory activity. Important interactions of the most active compound 3l (IC(50) = 6.24 µM) with the amino acid residues of the active site of XO were figured out by molecular modeling.


Assuntos
Compostos Aza/farmacologia , Flavonas/farmacologia , Xantina Oxidase/antagonistas & inibidores , Aminoácidos/química , Animais , Compostos Aza/síntese química , Compostos Aza/química , Bovinos , Desenho de Fármacos , Flavonas/síntese química , Flavonas/química , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Concentração Inibidora 50 , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade
9.
Indian J Clin Biochem ; 28(3): 248-54, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24426219

RESUMO

Human serum paraoxonase-1 (PON1), an enzyme on HDL prevents oxidation of LDL thereby preventing the development of atherosclerosis. Studies done so far have lead to conflicting results. As studies are lacking in North-West Indian Punjabi's, a distinct ethnic group with high incidence of coronary artery disease, we determined PONase activity in this population. It has been postulated that sudden lowering of serum PONase may lead to precipitation of acute myocardial infarction. We determined serum PONase activity and lipids in 100 patients each of AMI (within 24 h of onset), stable CAD and 100 age and sex matched healthy controls. These were again determined after 6 weeks in AMI patients. The mean serum PONase activity was lowest in AMI patients (23.26 U/ml) followed by stable CAD patients (102.0 U/ml) where as in controls was highest (179.8 U/ml). In patients with AMI, activity was significantly higher at 6 weeks as compared to that after acute event (49.39 %; p < 0.05). Sudden lowering of serum PONase activity in a population which already has lower activity may be one of the risk factors for development of AMI.

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