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1.
Philos Trans A Math Phys Eng Sci ; 382(2282): 20230271, 2024 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-39307167

RESUMEN

In this article, we report the modification and photocatalytic evaluation of commercial TiO2-P25 under visible light for methyl orange (MO) dye degradation under visible light. The activity of materials doped with N, Pd, Pt and Au on to the TiO2-P25 was evaluated, with optimal photocatalytic performance achieved using Au nanoparticles doped on an N-functionalized titania surface. X-ray diffraction (XRD), physical nitrogen adsorption/desorption isotherm curves, transmission electron microscopy (TEM), diffuse reflectance spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to study the structural and textural properties of the samples. The chemical species present in the bulk and surface of the catalysts were identified using X-ray photoelectron spectroscopy (XPS) and microwave plasma-atomic emission spectroscopy. The results show that Au/N-TiO2 photocatalyst presents a remarkable enhanced activity for MO dye degradation, under visible light illumination, reaching 100% after 4 h. The enhanced photocatalytic activity using this composite is attributable to the well-dispersed and small size of Au nanoparticles, large surface area, reduction of band-gap energy and the interaction between nitrogen and Au which promoted a synergistic effect. This article is part of the discussion meeting issue 'Green carbon for the chemical industry of the future'.

2.
Heliyon ; 9(8): e18748, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37576231

RESUMEN

The giant reed (Arundo donax) is a fast-growing plant adapted to different climatic and soil conditions; although its origin is Asian, the species has spread throughout the world. During its development, it consumes three times more water than typical native vegetation and is responsible for changing the landscape of riparian areas; the high biomass productivity and the annual harvest period make this crop an alternative to produce and/or extract industrial bioproducts. The main objective of this research was to evaluate the feasibility of using giant reed in a bioprocess that produces enzymes by a solid-state fermentation experiment, four fungal species were tested (Aspergillus niger GH1, Aspergillus niger PSH, Trichoderma harzianum, and Rhizopus oryzae); enzyme activities were performed using reported methodologies varying only reaction volumes. The A. niger GH1 and PSH strains were the best adapted to the plant material, A. niger GH1 was capable to produce 4 of the 5 evaluated enzymes (cellulase-endoglucanase (174.39 ± 19.62 U/L), xylanase (1313.31 ± 39.25 U/L), invertase (642.22 ± 23.55 U/L), and polyphenol oxidase (6094.01 ± 306.54) while A. niger PSH was able to produce 3 of the 5 evaluated enzymes (cellulase-endoglucanase (147.09 ± 13.88 U/L), xylanase (1307.76 ± 31.40 U/L), and invertase (603.92 ± 3.14 U/L).

3.
J Psychiatr Res ; 152: 366-374, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35793580

RESUMEN

BACKGROUND: Psychological interventions are commonly used to treat mild-to-moderate depression, but their efficacy in young adults has not been exhaustively addressed. This meta-analysis aims to establish it in comparison to no treatment, wait-list, usual treatment, passive interventions, and other bona-fide treatments. METHODS: The search was conducted in Scopus, MEDLINE, PsycINFO, ClinicalTrials.gov, the ISRCTN Registry, Cochrane CENTRAL, Clarivate BIOSIS Previews and the METAPSY database, retrieving studies from the start of records to April 2020. Eligibility criteria included samples of 16-30 years experiencing mild-to-moderate depressive symptoms and participating in randomized controlled trials (RCTs), non-RCTs, or pre-post studies measuring depressive symptomatology and featuring psychological treatments. RESULTS: Up to 45 studies met criteria, consisting of 3,947 participants, assessed using the Quality Assessment Tool for Quantitative Studies and their results meta-analyzed assuming random effects. Psychological interventions proved to be efficacious in RCTs compared to no treatment (g = -0.68; 95% CI = -0.87, -0.48) and wait-list (g = -1.04; 95% CI = -1.25, -0.82), while depressive symptoms also improved in pre-post studies (g = -0.99; 95% CI = -1.32, -0.66). However, intervention efficacy was similar to usual care, passive, and bona-fide comparators. The heterogeneity found, a likely reporting bias and the low quality of most studies must be considered when interpreting these results. CONCLUSIONS: Psychological treatments are efficacious to reduce depressive symptoms in young adults, but comparable to other interventions in the mild-to-moderate range. Moderators like depression severity or therapist involvement significantly influenced their efficacy, with results encouraging clinicians to adopt flexible and personalized approaches.


Asunto(s)
Depresión , Psicoterapia , Adolescente , Adulto , Depresión/diagnóstico , Depresión/terapia , Humanos , Intervención Psicosocial , Psicoterapia/métodos , Listas de Espera , Adulto Joven
4.
Oxid Med Cell Longev ; 2017: 8510761, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29163756

RESUMEN

The increase in the elderly population has generated concern to meet health demands. The research efforts to elucidate the mechanisms of damage associated with aging have also been significantly increased, especially in order to avoid the reduction of the cognitive abilities in geriatric patients, resulting from the damage generated mainly at the level of the hippocampus during old age. At present, many studies describe resveratrol as an antiaging component. There are reports that it can activate the Sirt1 gene related to antiaging, emulating the effects obtained by caloric restriction in rodents. The aim of the study was to evaluate the effect of chronic administration of resveratrol (10 mg/kg) on cognitive performance in behavioral tests after 8 months of treatment and on the preservation of cerebral integrity in the cytoarchitecture of regions CA1 and CA2. Results showed that the cytoarchitecture of the CA1 and CA2 regions in the hippocampus retained their integrity over time in rats treated with resveratrol, and the behavioral test performed revealed that chronic resveratrol administration for 8 months showed improvements in cognitive performance. The results indicate that resveratrol may exhibit therapeutic potential for age-related conditions.


Asunto(s)
Cognición/efectos de los fármacos , Estilbenos/uso terapéutico , Envejecimiento , Animales , Vías de Administración de Medicamentos , Masculino , Ratas , Ratas Wistar , Resveratrol , Estilbenos/farmacología
5.
Behav Brain Res ; 317: 562-575, 2017 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-27633561

RESUMEN

In rodents, the removal of the olfactory bulbs (OBs), i.e. olfactory bulbectomy (OBX), results in numerous alterations in neurotransmitter, endocrine and immune systems, as well as behavioral changes, similar to those observed in depressed patients. Because the behavioral deficits induced in OBX animals are reversed after repeated administration of antidepressants, this is a model often used to test the effectiveness of putative antidepressant agents. Recent evidence suggests that OBX results in the dysfunction of various cellular processes within the hippocampus, including decreases in dentate gyrus neurogenesis, disruption in long-term potentiation in CA1 and CA3 subregions and neuronal atrophy in the CA1 subregion, along with downstream markers, all of which are consistent with abnormal neuronal activity in the hippocampus of clinically depressed populations. Moreover, repeated administration of novel natural and synthetic antidepressant compounds can improve certain aspects of depression-like behavior and hippocampal function. In an effort to bring together the existing literature, this review will focus on the mechanisms by which proposed pharmaceuticals impact hippocampal-dependent processes and behavior.


Asunto(s)
Depresión , Modelos Animales de Enfermedad , Hipocampo/fisiología , Neurogénesis/fisiología , Bulbo Olfatorio/cirugía , Animales , Antiinflamatorios no Esteroideos/uso terapéutico , Antidepresivos/uso terapéutico , Curcumina/uso terapéutico , Depresión/tratamiento farmacológico , Hipocampo/efectos de los fármacos , Indanos/uso terapéutico , Potenciación a Largo Plazo/efectos de los fármacos , Neurogénesis/efectos de los fármacos , Bulbo Olfatorio/fisiología , Ratas , Compuestos de Espiro/uso terapéutico
6.
Mater Sci Eng C Mater Biol Appl ; 66: 119-129, 2016 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-27207045

RESUMEN

This work compares the surface modifications induced by the immersion in solutions that simulate inflammatory conditions of pure titanium (cpTi) and medical grade stainless steel (SS). The inflammatory conditions were simulated using a mixture of Hartman solution and 50mM of hydrogen peroxide (H2O2) at pH=5.2. The samples were immersed by 7days refreshing the solution every day to keep the reactivity of the H2O2. The surface characteristics that were investigated were: elemental composition by X-ray photoelectron spectroscopy (XPS); topography by atomic force microscopy (AFM) and profilometry; wettability and surface energy by sessile drop contact angle and point of zero charge by titration. Moreover, the variations in the electrochemical response were evaluated by open circuit potential (OCP), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PP) performed before and after the treatment using the Hartman solution as the electrolyte. The XPS results indicated that for both metallic samples, oxidation of the surface was promoted and/or the oxide layer was thicker after the immersion. The roughness and the solid-liquid surface energy were increased; the samples showed a more hydrophilic character after the treatment. However, the surface energy of the solid estimated using the Van Oss-Chaudhury-Good approach showed different trends between the cpTi and the SS surfaces; the polar component decreased for cpTi, while it increased for SS. Finally, the electrochemical results indicated that the corrosion resistance (Rcor) and the pore resistance (Rpo) significantly decreased for cpTi, while both resistances were not significantly different for the SS. This is indicative of a higher dissolution of the cpTi compared to SS and the lower Rpo means that the species are easily transported through the surface layer, which can be explained in terms of the formation of a porous TiOx layer, not observed on the SS. The cpTi surface suffered from a dissolution/oxidation process that allows its integration with the surrounding media, while the SS remained completely passive and this different response might be related to their distinguished clinical outcome.


Asunto(s)
Materiales Biocompatibles/química , Acero Inoxidable/química , Titanio/química , Técnicas Electroquímicas , Peróxido de Hidrógeno/química , Concentración de Iones de Hidrógeno , Microscopía de Fuerza Atómica , Espectroscopía de Fotoelectrones , Propiedades de Superficie , Timol/química , Humectabilidad
7.
Transplant Proc ; 48(2): 658-64, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27110024

RESUMEN

INTRODUCTION: In liver transplant (LT) recipients, surgical site infection (SSI) represents an important cause of morbidity and mortality. OBJECTIVE: This study measures the impact of a multimodal approach to the incidence of surgical site infection in LT recipients. MATERIALS AND METHODS: All of the LT recipients in our department were registered on the national database in solid organ transplant. A study was performed in two analytical-interventional phases. Phase 1 took place between July 14, 2009, and February 20, 2014. Phase 2 took place between February 21, 2014, and July 15, 2015. The multimodal change implemented during phase 1 was that 0.5% alcoholic chlorhexidine and ether were applied to the surgical field; surgical prophylaxis was primarily with ampicillin/sulbactam plus cefazolin. In phase 2, 2% alcoholic chlorhexidine alone was applied to the surgical field. The prior standard prophylaxis was changed to piperacillin tazobactam administered during surgery as a continuous infusion of 13.5 g over 8 hours with a pre-incision loading dose of 4.5 g. The loading dose of piperacillin tazobactam was combined with a single dose of gentamicin of 5 mg/kg. RESULTS: One hundred eight patients have received transplants since the start of the program: 82 patients during phase one and 26 patients during phase two. During phase 1, 13 cases of SSI were recorded, representing a rate of 15.85 per 100 transplants. Sixteen micro-organisms were isolated during phase 1, of which 12 corresponded to gram-negative bacilli. With regard to resistance profiles, 13 showed multidrug resistant and extensively drug resistant profiles. During phase 2, no cases of SSI were recorded (relative risk = 0.158 [95% confidence interval 0.0873-0.255], P = .0352]. CONCLUSION: A multimodal approach allowed for the reduction of the incidence of SSI in LTs and offered a protective strategy.


Asunto(s)
Antibacterianos/administración & dosificación , Infecciones por Bacterias Gramnegativas/prevención & control , Infecciones por Bacterias Grampositivas/prevención & control , Trasplante de Hígado/métodos , Infección de la Herida Quirúrgica/prevención & control , Administración Cutánea , Adulto , Ampicilina/administración & dosificación , Antiinfecciosos Locales/administración & dosificación , Profilaxis Antibiótica/métodos , Cefazolina/administración & dosificación , Clorhexidina/administración & dosificación , Esquema de Medicación , Quimioterapia Combinada , Éter/administración & dosificación , Femenino , Gentamicinas/administración & dosificación , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Ácido Penicilánico/administración & dosificación , Ácido Penicilánico/análogos & derivados , Piperacilina/administración & dosificación , Combinación Piperacilina y Tazobactam , Sulbactam/administración & dosificación , Receptores de Trasplantes
8.
Neuroscience ; 259: 84-93, 2014 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-24295633

RESUMEN

In this study, we investigated the effect of neonatal olfactory bulbectomy (nOBX) on behavioral paradigms related to olfaction such as exploratory behavior, locomotor activity in a novel environment and social interaction. We also studied the effect of nOBX on the activity of the N-methyl-d-aspartate (NMDA) subtype of glutamate receptors during development. The behavioral effects of nOBX (postnatal day 7, PD7) were investigated in pre- (PD30) and post-pubertal (PD60) Wistar rats. NMDA receptor activity was measured with [(125)I]MK-801 in the brain regions associated with the olfactory circuitry. A significant increase in the novelty-induced locomotion was seen in the pre-pubertal nOBX rats. Although the locomotor effect was less marked than in pre-pubertal rats, the nOBX rats tested post-pubertally failed to habituate to the novel situation as quickly as the sham- and normal- controls. Pre-pubertally, the head-dipping behavior was enhanced in nOBX rats compared with sham-operated and normal controls, while normal exploratory behavior was observed between groups in adulthood. In contrast, social interaction was increased in post-pubertal animals that underwent nOBX. Both pre- and post-pubertal nOBX rats recovered olfaction. Interestingly, pre-pubertal rats showed a significant increase in the [(125)I]MK-801 binding in the piriform cortex, dorsal hippocampus, inner and outer layers of the frontal cortex and outer layer of the cingulate cortex. At post-pubertal age, no significant differences in [(125)I]MK-801 binding were observed between groups at any of the brain regions analyzed. These results suggest that nOBX produces pre-pubertal behavioral disturbances and NMDA receptor changes that are transitory with recovery of olfaction early in adulthood.


Asunto(s)
Conducta Exploratoria/fisiología , Actividad Motora/fisiología , Bulbo Olfatorio/fisiología , Receptores de N-Metil-D-Aspartato/metabolismo , Olfato/fisiología , Factores de Edad , Animales , Animales Recién Nacidos , Maleato de Dizocilpina/farmacocinética , Femenino , Relaciones Interpersonales , Radioisótopos de Yodo/farmacocinética , Masculino , Bulbo Olfatorio/crecimiento & desarrollo , Bulbo Olfatorio/cirugía , Vías Olfatorias , Embarazo , Unión Proteica/fisiología , Ensayo de Unión Radioligante , Ratas , Ratas Wistar , Tiempo de Reacción/fisiología , Estadísticas no Paramétricas , Factores de Tiempo
9.
Neuroscience ; 236: 233-43, 2013 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-23357118

RESUMEN

Disturbances in olfactory circuitry have been associated with depression in humans. The olfactory bulbectomized (OBX lesion) has been largely used as a model of depression-like behavior in the rat. However, quantitative neuronal rearrangements in key brain regions in this animal model have not been evaluated yet. Accordingly, we investigated changes in hippocampal plasticity as well as behavioral deficits in this animal model. OBX-induced behavioral deficits were studied in a battery of tests, namely the open field test (OFT), forced swim test (FST), and spatial memory disturbances in the Morris water maze (MWM). To characterize the neuronal remodeling, neuroanatomical rearrangements were investigated in the CA1 hippocampus and piriform cortex (PirC), brain regions receiving inputs from the olfactory bulbs and associated with emotional or olfactory processes. Additionally, cell proliferation and survival of newborn cells in the adult dentate gyrus (DG) of the hippocampus were also determined. OBX induced hyperlocomotion and enhanced rearing and grooming in the OFT, increased immobility in the FST as well as required a longer time to find the hidden platform in the MWM. OBX also induced dendritic atrophy in the hippocampus and PirC. In addition, cell proliferation was decreased while the survival remained unchanged in the DG of these animals. These various features are also observed in depressed subjects, adding further support to the validity and usefulness of this model to evaluate potential novel antidepressants.


Asunto(s)
Síntomas Afectivos/patología , Hipocampo/patología , Trastornos de la Memoria/patología , Plasticidad Neuronal/fisiología , Bulbo Olfatorio/cirugía , Síntomas Afectivos/fisiopatología , Animales , Depresión/patología , Depresión/fisiopatología , Modelos Animales de Enfermedad , Hipocampo/fisiopatología , Inmunohistoquímica , Masculino , Trastornos de la Memoria/fisiopatología , Ratas , Ratas Sprague-Dawley
10.
Neuropeptides ; 46(6): 329-34, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23103057

RESUMEN

Recent studies from our groups have shown that BIIE0246, a Y2 receptor antagonist, has antidepressant effect in olfactory bulbectomized (OBX) rat. However, its complex structure and high molecular weight limit its usefulness as an in vivo pharmacological tool. Alternatively, the novel and brain penetrant Y2 receptor antagonist, JNJ-31020028 is a useful tool to investigate the in vivo function of the Y2 receptor. In the present study, we evaluated the effect of chronic intracerebroventricular (icv) administration of JNJ-31020028 in a battery of behavioral tests in an animal model that mimics several deficits observed in the human depression, the OBX rat. Chronic administration of JNJ-31020028 induced a decrease in immobility time in the forced swim test in OBX while had no effect in control animals. Additionally, it decreased number of grooming events in OBX animals, but had no effects on some other behavioral deficits observed such as rearing and hyperlocomotion. Furthermore, JNJ-31020028 had no effect on behavior tests that are commonly used to evaluate anxiety, namely the social interaction test in both OBX and control animals. These data indicate that similar to BIIE0246, JNJ-31020028 also has antidepressant like effects in the OBX model.


Asunto(s)
Antidepresivos , Conducta Animal/efectos de los fármacos , Benzamidas/farmacología , Bulbo Olfatorio/fisiología , Piperazinas/farmacología , Receptores de Neuropéptido Y/antagonistas & inhibidores , Animales , Benzamidas/administración & dosificación , Aseo Animal/efectos de los fármacos , Bombas de Infusión Implantables , Inyecciones Intraventriculares , Relaciones Interpersonales , Masculino , Actividad Motora/efectos de los fármacos , Piperazinas/administración & dosificación , Ratas , Ratas Sprague-Dawley , Natación/psicología
11.
Behav Brain Res ; 233(2): 298-304, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-22613731

RESUMEN

The neuropeptide Y (NPY) has been suggested to act as a major regulator of emotional processes and body weight. The full spectrum of biological effects of this peptide is mediated by at least four classes of receptors known as the Y(1), Y(2), Y(4), and Y(5) subtypes. However, the respective contribution of each of these receptor subtypes, especially the Y(5) subtype, in emotional processes is still mostly unknown. In the present study, we investigated the effect of long term administration of a selective Y(5) agonist [cPP(1-7),NPY(19-23),Ala(31),Aib(32),Gln(34)]hPP on emotional processes and body weight using two rat models of emotional dysfunctions, the corticosterone (CORT)-induced anxiety model as well as the olfactory bulbectomized (OBX) model of depression and anxiety in Wistar and Sprague-Dawley rats, respectively. The sub-chronic administration of the Y(5) agonist reversed the high levels of locomotion, rearing and grooming in the open field test and the impaired social activity induced by OBX, while increased the percentage of entries and time in the open arm of the elevated plus maze in CORT-treated rats. Furthermore, this Y(5) agonist increased body weight in both strains of control rats. These data further demonstrate that Y(5) receptors are not only involved in the control of body weight but also mediate emotional processing under challenged conditions. Thus, the pharmacotherapeutic administration of a Y(5) agonist could be considered as a potentially novel strategy to alleviate some forms of anxiety and depression in humans.


Asunto(s)
Peso Corporal/efectos de los fármacos , Emociones/efectos de los fármacos , Neuropéptido Y/análogos & derivados , Receptores de Neuropéptido Y/agonistas , Técnicas de Ablación/métodos , Análisis de Varianza , Animales , Antiinflamatorios/administración & dosificación , Corticosterona/administración & dosificación , Relación Dosis-Respuesta a Droga , Sistemas de Liberación de Medicamentos , Conducta Exploratoria/efectos de los fármacos , Pérdida de Tono Postural/efectos de los fármacos , Relaciones Interpersonales , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Neuropéptido Y/agonistas , Bulbo Olfatorio/cirugía , Fragmentos de Péptidos/farmacología , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Natación/psicología
12.
J Chemother ; 21(5): 527-34, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19933044

RESUMEN

A one-day point prevalence study to investigate the patterns of antibiotic use was undertaken in 43 latin American (LA) intensive care units. Of 510 patients admitted, 231 received antibiotic treatment on the day of the study (45%); in 125 cases (54%) due to nosocomial-acquired infections. The most frequent infection reported was nosocomial pneumonia (43%). Only in 122 patients (53%) were cultures performed before starting antibiotic treatment. 33% of the isolated microorganisms were enterobacteriaceae (40% extended-spectrum beta-lactamase-producing), 23% methicillin-resistant Staphylococcus aureus and 17% carbapenems-resistant non-fermentative Gram-negatives. The antibiotics most frequently prescribed were carbapenems (99/231, 43%); alone (60/99, 60%) or in combination with vancomycin (39/99, 40%). "Restricted" antibiotics (carbapenems, vancomycin, piperacillin-tazobactam, broad-spectrum cephalosporins, tigecycline, polymixins and linezolid) were most frequently indicated in severely ill patients (APACHE II score at admission >15, p=0.0007 and, SOFA score at the beginning of the antibiotic treatment >3, p=0.0000). Only 36% of antibiotic treatments were cultured-directed.Our findings help explain the high rates of multidrug-resistant pathogens in LA settings (i.e. ESBL-producing Gram-negatives) and the severity of the registered patients illnesses.


Asunto(s)
Antibacterianos/uso terapéutico , Bacterias/aislamiento & purificación , Infección Hospitalaria/tratamiento farmacológico , Prescripciones de Medicamentos/estadística & datos numéricos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Pautas de la Práctica en Medicina , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bacterias/efectos de los fármacos , Infección Hospitalaria/microbiología , Estudios Transversales , Farmacorresistencia Bacteriana , Resistencia a Múltiples Medicamentos , Femenino , Hospitalización/estadística & datos numéricos , Humanos , América Latina , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Adulto Joven
13.
Br J Cancer ; 100(11): 1755-64, 2009 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-19436305

RESUMEN

Liver and lung metastases are the predominant cause of colorectal cancer (CRC)-related mortality. Recent research has indicated that CXCR3/chemokines interactions that orchestrate haematopoetic cell movement are implicated in the metastatic process of malignant tumours, including that of CRC cells to lymph nodes. To date, however, the contribution of CXCR3 to liver and lung metastasis in CRC has not been addressed. To determine whether CXCR3 receptors regulate malignancy-related properties of CRC cells, we have used CXCR3-expressing CRC cell lines of human (HT29 cells) and murine (C26 cells) origins that enable the development of liver and lung metastases when injected into immunodeficient and immunocompetent mice, respectively, and assessed the effect of CXCR3 blockade using AMG487, a small molecular weight antagonist. In vitro, activation of CXCR3 on human and mouse CRC cells by its cognate ligands induced migratory and growth responses, both activities being abrogated by AMG487. In vivo, systemic CXCR3 antagonism by preventive or curative treatments with AMG487 markedly inhibited the implantation and the growth of human and mouse CRC cells within lung without affecting that in the liver. In addition, we measured increased levels of CXCR3 and ligands expression within lung nodules compared with liver tumours. Altogether, our findings indicate that activation of CXCR3 receptors by its cognate ligands facilitates the implantation and the progression of CRC cells within lung tissues and that inhibition of this axis decreases pulmonary metastasis of CRC in two murine tumour models.


Asunto(s)
Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Receptores CXCR3/antagonistas & inhibidores , Animales , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Movimiento Celular , Neoplasias del Colon/tratamiento farmacológico , Humanos , Ligandos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundario , Ratones , Trasplante de Neoplasias , Especificidad de Órganos , Receptores CXCR3/metabolismo , Tasa de Supervivencia
15.
Mol Biol Rep ; 35(3): 473-8, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17577681

RESUMEN

The human multidrug resistance gene (MDR1) encodes for P-glycoprotein (P-gp) which is a transmembrane transporter protein that acts as an efflux pump for a number of lypophilic compounds. It plays a protective role for cells against DNA damage. The wobble C3435T polymorphism at exon 26 has been associated with different expression levels and activity. Differences in allele frequency of the C3435T polymorphism have been demonstrated between distinct ethnic groups. In our study we examined these polymorphisms in 433 healthy individuals. From these, 229 were Central American mestizos from Nicaragua (n = 117) and El Salvador (n = 112) to be compared with a group of 204 North Spaniards, with the aim of detecting potential genotypic differences between these populations. The genotypes were determined by PCR-RFLP. The frequencies of the C allele were very similar among Central Americans (0.53) and Spaniards (0.52), which is consistent with the ethnic origin of Central American individuals (Amerindians and European Caucasians). In comparison to other previously studied populations, the C allele frequency in Central Americans was significantly lower than that found in African populations and higher than that observed in the Indian and Southwest Asian populations. These data may be relevant for dose recommendation of P-gp substrate drugs and also for studies of allele disease association in the Central American population.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Polimorfismo Genético/genética , Alelos , América Central/etnología , Citidina/genética , Genotipo , Humanos , España/etnología , Timidina/genética
16.
Arch Cardiol Mex ; 71(2): 151-9, 2001.
Artículo en Español | MEDLINE | ID: mdl-11565308

RESUMEN

The reason for multisite pacing is to correct atrial and ventricular electrical and mechanical asynchrony found in paroxysmal atrial fibrillation (PAF) and dilated cardiomyopathy. We report the first two cases in Mexico treated with biatrial pacing for PAF. The first was treated with a three chamber pacemaker and the other with a four chamber pacemaker. The first patient was a young man with uncontrolled ventricular rate in whom the atrioventricular conduction was modified with radiofrequency energy to control ventricular rate during atrial fibrillation. The second patient was a woman with corrected transposition of the great arteries, left ventricular ejection fraction (LVEF) of 30% and complete heart block. The pacing modalities were DDD for the first patient and DDDR for the second, both with sleep rate and auto mode switching. The atria were paced in right appendage and the left through the coronary sinus. PAF episodes were, found only in the first patient but were decreased in number and duration. The LVEF and functional class improved in the patient with biatrial and ventricular resynchronization. We conclude that biatrial pacing is effective in PAF.


Asunto(s)
Fibrilación Atrial/terapia , Marcapaso Artificial , Adulto , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad
17.
Anal Chem ; 73(6): 1301-6, 2001 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-11305667

RESUMEN

Experimental peak capacities for capillary gas chromatography (GC), capillary liquid chromatography (CLC), and capillary electrochromatography (CEC) were compared. To obtain a meaningful comparison, the following constraints were applied. First, the same sample (mixture of alkylbenzenes) was used as a test mixture for all three techniques; second, the same packing material and column diameter were used in CLC and CEC; and third, isothermal conditions were used in GC, while isocratic conditions were used both in CLC and in CEC. Comparison of peak capacities for the same total column efficiency (approximately 36000 plates) showed that the peak capacity of GC is greater than those of the liquid-phase separation techniques. Comparison of CEC and CLC for constant retention factor was also carried out. For this condition, the results depend on the particle size used; for 3-microm porous particles, CEC had a peak capacity larger than CLC due to higher efficiency from the flow profile generated by electroosmotic flow. However, when 1.5-microm nonporous particles were used, the peak capacities were approximately the same for both techniques. The effect of linear velocity on peak capacity was also studied for all three techniques. Practical conditions aimed at increasing peak capacities of liquid-phase separation techniques are discussed.

18.
Genes Dev ; 14(22): 2831-8, 2000 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11090131

RESUMEN

The discovery of oxysterols as the endogenous liver X receptor (LXR) ligands and subsequent gene targeting studies in mice provided strong evidence that LXR plays a central role in cholesterol metabolism. The identification here of a synthetic, nonsteroidal LXR-selective agonist series represented by T0314407 and T0901317 revealed a novel physiological role of LXR. Oral administration of T0901317 to mice and hamsters showed that LXR activated the coordinate expression of major fatty acid biosynthetic genes (lipogenesis) and increased plasma triglyceride and phospholipid levels in both species. Complementary studies in cell culture and animals suggested that the increase in plasma lipids occurs via LXR-mediated induction of the sterol regulatory element-binding protein 1 (SREBP-1) lipogenic program.


Asunto(s)
Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Proteínas de Unión al ADN/metabolismo , Lípidos/biosíntesis , Receptores Citoplasmáticos y Nucleares/agonistas , Sulfonamidas/farmacología , Factores de Transcripción , Animales , Cricetinae , Relación Dosis-Respuesta a Droga , Ácidos Grasos/biosíntesis , Hipertrigliceridemia/etiología , Lipoproteínas/sangre , Hígado/metabolismo , Receptores X del Hígado , Ratones , Ratones Mutantes , Receptores Nucleares Huérfanos , Fosfolípidos/sangre , Proteína 1 de Unión a los Elementos Reguladores de Esteroles , Triglicéridos/sangre
19.
Arch Inst Cardiol Mex ; 70(4): 391-8, 2000.
Artículo en Español | MEDLINE | ID: mdl-11075285

RESUMEN

This article describes the first case in Mexico city that received a three chamber pacing system. A 40 year-old man with dilated cardiomyopathy with variant cardiac rhythm and bradycardia. The three leads were introduced by right subclavian approaches. The right chamber leads were placed in atrial's appendage and in the right ventricular outflow tract and the last one was placed in the great cardiac vein. The two ventricular lead were connected a Y-connector to the ventricular channel of a standard bipolar DDDR pacemaker. The right ventricular lead was connected to the distal pole (anode) and the left ventricular lead to the proximal pole (cathode). Eight days later, the patient's clinical status improved, his functional class improved from IV to II and his left ventricular ejection fraction increased from 30% to 35% by conventional ventriculography. In this type of patients the improvement in cardiac output is this result an of increase in left ventricular filling, reduced mitral and tricuspid regurgitation a better synchronization of ventricular contraction. Multisite pacing has added a mayor complexity to contemporary pacing and a modification of the standard pacer-maker code should be considered to accommodate multisite pacing. The letter in the first and second position might be T (three) or F (four) according to number of pacing chamber and also the letter "t" may be suitable to designate trigger in the third position. We conclude that implant of three chamber pacing in patients with dilated cardiomyopathy is technically feasible. An improvement in the patient's condition may be obtained and a modification in standard pacemaker code is necessary.


Asunto(s)
Estimulación Cardíaca Artificial/métodos , Cardiomiopatía Dilatada/terapia , Marcapaso Artificial , Adulto , Cateterismo Cardíaco , Humanos , Masculino
20.
J Chromatogr A ; 892(1-2): 3-13, 2000 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-11045476

RESUMEN

Packed capillary column solvating gas chromatography (SGC) and open tubular column gas chromatography (GC) were compared with respect to their potentials for fast separations. A recently introduced "universal" peak capacity equation was used to compare the performance of these two methods. The effects of various factors on peak capacity were investigated. Results demonstrate that retention factor and column efficiency are the main factors affecting peak capacity for fast separations. Packed columns produce both high retention factors and high selectivities. While high efficiencies and high peak capacities can be demonstrated by both techniques, open tubular column GC can surpass packed capillary column SGC in both measurements, except for the case of the analysis of simple mixtures in short analysis times, where retention factor and selectivity become important. Practical aspects such as pressure drop and sample capacity are compared for SGC and open tubular column GC. It was found that packed column SGC demonstrates higher sample capacities, but requires much higher column inlet pressures than open tubular column GC. A variety of mobile phases can be used for packed column SGC, which can provide high solvating power for large and polar compounds.


Asunto(s)
Cromatografía de Gases/métodos , Sensibilidad y Especificidad
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