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1.
Chemistry ; 29(24): e202203990, 2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-36734519

RESUMEN

A combined experimental and theoretical study has been carried out on 4-fluoro-threonine, the only naturally occurring fluorinated amino acid. Fluorination of the methyl group significantly increases the conformational complexity with respect to the parent amino acid threonine. The conformational landscape has been characterized in great detail, with special attention given to the inter-conversion pathways between different conformers. This led to the identification of 13 stable low-energy minima. The equilibrium population of so many conformers produces a very complicated and congested rotational spectrum that could be assigned through a strategy that combines several levels of quantum chemical calculations with the principles of machine learning. Twelve conformers out of 13 could be experimentally characterized. The results obtained from the analysis of the intra-molecular interactions can be exploited to accurately model fluorine-substitution effects in biomolecules.

2.
Anim Genet ; 49(3): 147-158, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29624711

RESUMEN

The 'omics revolution has made a large amount of sequence data available to researchers and the industry. This has had a profound impact in the field of bioinformatics, stimulating unprecedented advancements in this discipline. Mostly, this is usually looked at from the perspective of human 'omics, in particular human genomics. Plant and animal genomics, however, have also been deeply influenced by next-generation sequencing technologies, with several genomics applications now popular among researchers and the breeding industry. Genomics tends to generate huge amounts of data, and genomic sequence data account for an increasing proportion of big data in biological sciences, due largely to decreasing sequencing and genotyping costs and to large-scale sequencing and resequencing projects. The analysis of big data poses a challenge to scientists, as data gathering currently takes place at a faster pace than does data processing and analysis, and the associated computational burden is increasingly taxing, making even simple manipulation, visualization and transferring of data a cumbersome operation. The time consumed by the processing and analysing of huge data sets may be at the expense of data quality assessment and critical interpretation. Additionally, when analysing lots of data, something is likely to go awry-the software may crash or stop-and it can be very frustrating to track the error. We herein review the most relevant issues related to tackling these challenges and problems, from the perspective of animal genomics, and provide researchers that lack extensive computing experience with guidelines that will help when processing large genomic data sets.


Asunto(s)
Biología Computacional , Genómica , Análisis de Secuencia de ADN , Animales , Bases de Datos Genéticas , Secuenciación de Nucleótidos de Alto Rendimiento , Internet , Programas Informáticos
3.
Chem Commun (Camb) ; 53(10): 1591-1594, 2017 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-28085164

RESUMEN

Using ascorbate as a sacrificial reductant, iodo-Bodipy dye 1b is able to promote the ATRA reaction between bromoderivatives and alkenes. This finding expands the possibility of using Bodipy dyes to promote photocatalytic reactions in efficient ways.

4.
Nanoscale ; 8(28): 13678-86, 2016 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-27376633

RESUMEN

Tuning the intermolecular interactions among suitably designed molecules forming highly ordered self-assembled monolayers is a viable approach to control their organization at the supramolecular level. Such a tuning is particularly important when applied to sophisticated molecules combining functional units which possess specific electronic properties, such as electron/energy transfer, in order to develop multifunctional systems. Here we have synthesized two tetraferrocene-porphyrin derivatives that by design can selectively self-assemble at the graphite/liquid interface into either face-on or edge-on monolayer-thick architectures. The former supramolecular arrangement consists of two-dimensional planar networks based on hydrogen bonding among adjacent molecules whereas the latter relies on columnar assembly generated through intermolecular van der Waals interactions. Scanning Tunneling Microscopy (STM) at the solid-liquid interface has been corroborated by cyclic voltammetry measurements and assessed by theoretical calculations to gain multiscale insight into the arrangement of the molecule with respect to the basal plane of the surface. The STM analysis allowed the visualization of these assemblies with a sub-nanometer resolution, and cyclic voltammetry measurements provided direct evidence of the interactions of porphyrin and ferrocene with the graphite surface and offered also insight into the dynamics within the face-on and edge-on assemblies. The experimental findings were supported by theoretical calculations to shed light on the electronic and other physical properties of both assemblies. The capability to engineer the functional nanopatterns through self-assembly of porphyrins containing ferrocene units is a key step toward the bottom-up construction of multifunctional molecular nanostructures and nanodevices.

5.
Cell Death Dis ; 5: e1437, 2014 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-25275598

RESUMEN

The PI3K/Akt/mTOR pathway has a central role in cancer metastasis and radiotherapy. To develop effective therapeutics to improve radiosensitivity, understanding the possible pathways of radioresistance involved and the effects of a combination of the PI3K/Akt/mTOR inhibitors with radiotherapy on prostate cancer (CaP) radioresistant cells is needed. We found that compared with parent CaP cells, CaP-radioresistant cells demonstrated G0/G1 and S phase arrest, activation of cell cycle check point, autophagy and DNA repair pathway proteins, and inactivation of apoptotic proteins. We also demonstrated that compared with combination of single PI3K or mTOR inhibitors (BKM120 or Rapamycin) and radiation, low-dose of dual PI3K/mTOR inhibitors (BEZ235 or PI103) combined with radiation greatly improved treatment efficacy by repressing colony formation, inducing more apoptosis, leading to the arrest of the G2/M phase, increased double-strand break levels and less inactivation of cell cycle check point, autophagy and non-homologous end joining (NHEJ)/homologous recombination (HR) repair pathway proteins in CaP-radioresistant cells. This study describes the possible pathways associated with CaP radioresistance and demonstrates the putative mechanisms of the radiosensitization effect in CaP-resistant cells in the combination treatment. The findings from this study suggest that the combination of dual PI3K/Akt/mTOR inhibitors (BEZ235 or PI103) with radiotherapy is a promising modality for the treatment of CaP to overcome radioresistance.


Asunto(s)
Autofagia , Reparación del ADN por Unión de Extremidades , Inhibidores Enzimáticos/farmacología , Recombinación Homóloga , Inhibidores de las Quinasa Fosfoinosítidos-3 , Neoplasias de la Próstata/fisiopatología , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Ciclo Celular/efectos de los fármacos , Ciclo Celular/efectos de la radiación , Línea Celular Tumoral , Reparación del ADN por Unión de Extremidades/efectos de los fármacos , Reparación del ADN por Unión de Extremidades/efectos de la radiación , Recombinación Homóloga/efectos de los fármacos , Recombinación Homóloga/efectos de la radiación , Humanos , Masculino , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/radioterapia , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Tolerancia a Radiación/efectos de los fármacos , Tolerancia a Radiación/efectos de la radiación , Transducción de Señal/efectos de los fármacos , Transducción de Señal/efectos de la radiación , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo
6.
Cell Death Dis ; 4: e875, 2013 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-24157869

RESUMEN

Radioresistance is a major challenge in prostate cancer (CaP) radiotherapy (RT). In this study, we investigated the role and association of epithelial-mesenchymal transition (EMT), cancer stem cells (CSCs) and the PI3K/Akt/mTOR signaling pathway in CaP radioresistance. We developed three novel CaP radioresistant (RR) cell lines (PC-3RR, DU145RR and LNCaPRR) by radiation treatment and confirmed their radioresistance using a clonogenic survival assay. Compared with untreated CaP-control cells, the CaP-RR cells had increased colony formation, invasion ability and spheroid formation capability (P<0.05). In addition, enhanced EMT/CSC phenotypes and activation of the checkpoint proteins (Chk1 and Chk2) and the PI3K/Akt/mTOR signaling pathway proteins were also found in CaP-RR cells using immunofluorescence, western blotting and quantitative real-time PCR (qRT-PCR). Furthermore, combination of a dual PI3K/mTOR inhibitor (BEZ235) with RT effectively increased radiosensitivity and induced more apoptosis in CaP-RR cells, concomitantly correlated with the reduced expression of EMT/CSC markers and the PI3K/Akt/mTOR signaling pathway proteins compared with RT alone. Our findings indicate that CaP radioresistance is associated with EMT and enhanced CSC phenotypes via activation of the PI3K/Akt/mTOR signaling pathway, and that the combination of BEZ235 with RT is a promising modality to overcome radioresistance in the treatment of CaP. This combination approach warrants future in vivo animal study and clinical trials.


Asunto(s)
Transición Epitelial-Mesenquimal , Células Madre Neoplásicas/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Tolerancia a Radiación , Serina-Treonina Quinasas TOR/metabolismo , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Puntos de Control del Ciclo Celular/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de la radiación , Línea Celular Tumoral , Activación Enzimática/efectos de los fármacos , Activación Enzimática/efectos de la radiación , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de la radiación , Humanos , Imidazoles/farmacología , Imidazoles/uso terapéutico , Masculino , Modelos Biológicos , Invasividad Neoplásica , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/enzimología , Fenotipo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/radioterapia , Quinolinas/farmacología , Quinolinas/uso terapéutico , Tolerancia a Radiación/efectos de los fármacos , Tolerancia a Radiación/efectos de la radiación , Reproducibilidad de los Resultados , Transducción de Señal/efectos de los fármacos , Transducción de Señal/efectos de la radiación , Esferoides Celulares/efectos de los fármacos , Esferoides Celulares/patología , Esferoides Celulares/efectos de la radiación , Serina-Treonina Quinasas TOR/antagonistas & inhibidores
7.
Br J Cancer ; 106(4): 638-45, 2012 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-22274410

RESUMEN

BACKGROUND: Men diagnosed with localised prostate cancer (LPC) face difficult choices between treatment options that can cause persistent problems with sexual, urinary and bowel function. Controlled trial evidence about the survival benefits of the full range of treatment alternatives is limited, and patients' views on the survival gains that might justify these problems have not been quantified. METHODS: A discrete choice experiment (DCE) was administered in a random subsample (n=357, stratified by treatment) of a population-based sample (n=1381) of men, recurrence-free 3 years after diagnosis of LPC, and 65 age-matched controls (without prostate cancer). Survival gains needed to justify persistent problems were estimated by substituting side effect and survival parameters from the DCE into an equation for compensating variation (adapted from welfare economics). RESULTS: Median (2.5, 97.5 centiles) survival benefits needed to justify severe erectile dysfunction and severe loss of libido were 4.0 (3.4, 4.6) and 5.0 (4.9, 5.2) months. These problems were common, particularly after androgen deprivation therapy (ADT): 40 and 41% overall (n=1381) and 88 and 78% in the ADT group (n=33). Urinary leakage (most prevalent after radical prostatectomy (n=839, mild 41%, severe 18%)) needed 4.2 (4.1, 4.3) and 27.7 (26.9, 28.5) months survival benefit, respectively. Mild bowel problems (most prevalent (30%) after external beam radiotherapy (n=106)) needed 6.2 (6.1, 6.4) months survival benefit. CONCLUSION: Emerging evidence about survival benefits can be assessed against these patient-based benchmarks. Considerable variation in trade-offs among individuals underlines the need to inform patients of long-term consequences and incorporate patient preferences into treatment decisions.


Asunto(s)
Prioridad del Paciente , Neoplasias de la Próstata/terapia , Anciano , Antagonistas de Andrógenos/efectos adversos , Supervivencia sin Enfermedad , Disfunción Eréctil/epidemiología , Humanos , Enfermedades Intestinales/epidemiología , Masculino , Persona de Mediana Edad , Prostatectomía/efectos adversos , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/psicología , Calidad de Vida , Radioterapia/efectos adversos , Enfermedades Urológicas/epidemiología
8.
Br J Cancer ; 103(7): 1008-18, 2010 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-20736947

RESUMEN

BACKGROUND: The aim of this study is to seek an association between markers of metastatic potential, drug resistance-related protein and monocarboxylate transporters in prostate cancer (CaP). METHODS: We evaluated the expression of invasive markers (CD147, CD44v3-10), drug-resistance protein (MDR1) and monocarboxylate transporters (MCT1 and MCT4) in CaP metastatic cell lines and CaP tissue microarrays (n=140) by immunostaining. The co-expression of CD147 and CD44v3-10 with that of MDR1, MCT1 and MCT4 in CaP cell lines was evaluated using confocal microscopy. The relationship between the expression of CD147 and CD44v3-10 and the sensitivity (IC(50)) to docetaxel in CaP cell lines was assessed using MTT assay. The relationship between expression of CD44v3-10, MDR1 and MCT4 and various clinicopathological CaP progression parameters was examined. RESULTS: CD147 and CD44v3-10 were co-expressed with MDR1, MCT1 and MCT4 in primary and metastatic CaP cells. Both CD147 and CD44v3-10 expression levels were inversely related to docetaxel sensitivity (IC(50)) in metastatic CaP cell lines. Overexpression of CD44v3-10, MDR1 and MCT4 was found in most primary CaP tissues, and was significantly associated with CaP progression. CONCLUSIONS: Our results suggest that the overexpression of CD147, CD44v3-10, MDR1 and MCT4 is associated with CaP progression. Expression of both CD147 and CD44v3-10 is correlated with drug resistance during CaP metastasis and could be a useful potential therapeutic target in advanced disease.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Basigina/metabolismo , Receptores de Hialuranos/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Neoplasias de la Próstata/metabolismo , Subfamilia B de Transportador de Casetes de Unión a ATP , Adulto , Anciano , Animales , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Progresión de la Enfermedad , Docetaxel , Resistencia a Antineoplásicos , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Neoplasias de la Próstata/tratamiento farmacológico , Taxoides/uso terapéutico , Regulación hacia Arriba
9.
Minerva Anestesiol ; 76(7): 550-3, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20613697

RESUMEN

The aim of this paper was to describe a case of acute liver failure treated with total hepatectomy, recombinant activated factor VII and rescue liver transplantation. We reported our experience with a 51-year-old-woman who developed a massive portal thrombosis after cadaveric liver transplantation for hepatic epithelioid hemangioendothelioma and who then required a total hepatectomy and porto-caval shunt as a bridge procedure while waiting for an urgent new liver transplantation. Subsequently, the patient developed severe hemodynamic instability, massive abdominal and mucosal bleeding and acute renal failure that were managed with infusion of high doses of inotropes, red blood cells and fresh frozen plasma as well as continuous veno-venous hemofiltration. Due to persistent, uncontrolled bleeding, we considered the off-label use of rFVIIa. This caused a correction of the prothrombin times and allowed for sufficient hemostasis. The patient received a new cadaveric liver that was reperfused 38 hours after the first graft was removed. The transplanted liver showed immediate recovery, the hemodynamics ameliorated and the patient was fully awake at day five. In the case of an anhepatic phase complicated by severe bleeding that is unresponsiveness to several transfusions, a single administration of rFVIIa should be considered as a rescue therapy to control massive bleeding.


Asunto(s)
Factor VIIa/uso terapéutico , Hepatectomía , Fallo Hepático Agudo/terapia , Trasplante de Hígado , Terapia Combinada , Femenino , Hepatectomía/métodos , Humanos , Persona de Mediana Edad , Proteínas Recombinantes/uso terapéutico
10.
Curr Cancer Drug Targets ; 10(3): 287-306, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20370680

RESUMEN

Prostate cancer (CaP) is a major health problem in males in Western countries. Current therapeutic approaches are limited and many patients die of secondary disease (metastases). There is no cure for metastatic castration-resistant prostate cancer (CRPC). Targeting tumor-associated antigens is fast emerging as an area of promise to treat late stage and recurrent CaP. Extracellular matrix metalloproteinase inducer, EMMPRIN (CD147) is a multifunctional glycoprotein that can modify the tumor microenvironment by activating proteinases, inducing angiogenic factors in tumor and stromal cells, and regulating growth and survival of anchorage-independent tumor cells (micrometastases) and multidrug resistance (MDR). CD44 is a multifunctional protein involved in cell adhesion, migration and drug resistance, and is a primary receptor for hyaluronan (HA), a major component of the extracellular matrix (ECM) with a critical role in cell signaling and cell-ECM interactions in cancer. Our recent studies indicate both CD147 and CD44 are involved in cancer drug resistance and play very important roles in CaP metastasis. Thus, CD147 and CD44 may be ideal therapeutic targets to control metastatic and CRPC disease. This review will discuss their putative roles in CaP metastasis and MDR, and give an overview of literature regarding their expression on human CaP tissues. Additional focus will be on the potential of therapeutic strategies targeting CD147 and CD44 to prevent CaP metastasis and overcome drug resistance.


Asunto(s)
Antineoplásicos/uso terapéutico , Basigina/metabolismo , Biomarcadores de Tumor/metabolismo , Terapia Genética , Receptores de Hialuranos/metabolismo , Inmunoterapia , Neoplasias de la Próstata/terapia , Animales , Basigina/genética , Biomarcadores de Tumor/genética , Adhesión Celular , Movimiento Celular , Resistencia a Antineoplásicos , Humanos , Receptores de Hialuranos/genética , Ácido Hialurónico/metabolismo , Masculino , Transportadores de Ácidos Monocarboxílicos/metabolismo , Invasividad Neoplásica , Células Madre Neoplásicas/inmunología , Células Madre Neoplásicas/patología , Neovascularización Patológica/genética , Neovascularización Patológica/inmunología , Neovascularización Patológica/prevención & control , Neoplasias de la Próstata/irrigación sanguínea , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/secundario , Resultado del Tratamiento
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