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1.
Pharmacol Ther ; 240: 108301, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36283453

RESUMEN

Malignant melanoma is the most lethal type of skin cancer with high rates of mortality. Although current treatment options provide a short-clinical benefit, acquired-drug resistance highlights the low 5-year survival rate among patients with advanced stage of the disease. In parallel, the involvement of an aberrant epigenetic landscape, (e.g., alterations in DNA methylation patterns, histone modifications marks and expression of non-coding RNAs), in addition to the genetic background, has been also associated with the onset and progression of melanoma. In this review article, we report on current therapeutic options in melanoma treatment with a focus on distinct epigenetic alterations and how their reversal, by specific drug compounds, can restore a normal phenotype. In particular, we concentrate on how single and/or combinatorial therapeutic approaches have utilized epigenetic drug compounds in being effective against malignant melanoma. Finally, the role of deregulated epigenetic mechanisms in promoting drug resistance to targeted therapies and immune checkpoint inhibitors is presented leading to the development of newly synthesized and/or improved drug compounds capable of targeting the epigenome of malignant melanoma.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Epigenoma , Melanoma/tratamiento farmacológico , Melanoma/genética , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/genética , Epigénesis Genética , Metilación de ADN , Melanoma Cutáneo Maligno
2.
Trends Biotechnol ; 40(1): 107-123, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34229865

RESUMEN

Cell membranes are integral to the functioning of the cell and are therefore key to drive fundamental understanding of biological processes for downstream applications. Here, we review the current state-of-the-art with respect to biomembrane systems and electronic substrates, with a view of how the field has evolved towards creating biomimetic conditions and improving detection sensitivity. Of particular interest are conducting polymers, a class of electroactive polymers, which have the potential to create the next step-change for bioelectronics devices. Lastly, we discuss the impact these types of devices could have for biomedical applications.


Asunto(s)
Técnicas Biosensibles , Electrónica , Biomimética , Técnicas Biosensibles/métodos , Membrana Celular , Polímeros
3.
J Small Anim Pract ; 63(3): 197-202, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34796970

RESUMEN

OBJECTIVES: To determine the prevalence of stress hyperglycaemia in sick cats, and to investigate the association of stress hyperglycaemia with systemic inflammatory response syndrome and outcome. MATERIALS AND METHODS: Medical records (2004 to 2013) from sick cats admitted to the Medicine Unit of a Veterinary Teaching Hospital were retrospectively reviewed. Cases were enrolled if a serum glucose measurement and a complete medical record were available. Cats that were healthy, hypoglycaemic, diabetic, sedated or had a previous administration of drugs (apart from vaccination and deworming) were excluded. RESULTS: The study included 647 cats; stress hyperglycaemia (serum glucose >8.3 mmol/L) was found in 194 (30%) cats, while 453 (70%) cats were normoglycaemic. The prevalence of systemic inflammatory response syndrome was significantly higher in cats with stress hyperglycaemia (25/174, 14.4%) compared to normoglycaemic cats (26/399, 6.5%). Significantly, more cats with stress hyperglycaemia were hospitalised [97/194 (50.0%)] compared to normoglycaemic cats [171/453 (37.7%)]. However, the median duration of hospitalisation was not significantly different [4 (1 to 26) days and 4 (1 to 24) days, respectively]. The prevalence of cats with negative outcome was not significantly different between the two groups (cats with stress hyperglycaemia: 37.1%, normoglycaemic cats: 33.9%). Nonetheless, when modelling of outcome prediction included breed, age, stress hyperglycaemia and disease category as factors, cats with stress hyperglycaemia had 2.8 times the odds to have a negative outcome (95% confidence interval: 1.3 to 6.4). CLINICAL SIGNIFICANCE: Based on the cut-off employed in this study, Stress hyperglycaemia, as defined by the cut-off is common in sick cats. Stress hyperglycaemia is associated with systemic inflammatory response syndrome development and seem to be a negative prognostic indicator.


Asunto(s)
Enfermedades de los Gatos , Hiperglucemia , Animales , Glucemia , Enfermedades de los Gatos/epidemiología , Gatos , Glucosa , Hospitales Veterinarios , Hospitales de Enseñanza , Hiperglucemia/epidemiología , Hiperglucemia/veterinaria , Prevalencia , Estudios Retrospectivos , Síndrome de Respuesta Inflamatoria Sistémica/epidemiología , Síndrome de Respuesta Inflamatoria Sistémica/veterinaria
4.
Benef Microbes ; 9(6): 975-983, 2018 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-30353740

RESUMEN

Lactobacillus paracasei K5 is a lactic acid bacteria (LAB) strain, isolated recently from feta-type cheese. Its probiotic potential has been demonstrated in a series of established in vitro tests. Moreover, incorporation of L. paracasei K5 as starter culture offered organoleptic and technological advantages to novel fermented food products. In the present study, further investigation of the potential probiotic activity of L. paracasei K5 was performed and its mechanisms of action were investigated. Employing quantitative analysis and confocal, fluorescent microscopy the adhesion properties of the above strain were studied. L. paracasei K5 displayed efficient adherence capacity to Caco-2 colon cancer cells, similarly to the reference strains Lactobacillus casei ATCC 393 and Lactobacillus rhamnosus GG. Moreover, treatment of Caco-2 cells with L. paracasei K5 inhibited cell proliferation in a time-and dose-dependent manner. The anti-proliferative effects appear to be mediated through induction of apoptosis via modulation of expression of specific Bcl-2 family proteins. These results elucidate the mechanisms of action of L. paracasei K5 and enhance its potential probiotic activity.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/tratamiento farmacológico , Lacticaseibacillus rhamnosus/fisiología , Probióticos/farmacología , Antineoplásicos/administración & dosificación , Adhesión Bacteriana , Células CACO-2 , Humanos , Microscopía Confocal , Microscopía Fluorescente , Modelos Teóricos , Probióticos/administración & dosificación
5.
Sci Rep ; 8(1): 10724, 2018 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-30013176

RESUMEN

In the present study, we have aimed to characterize the intrinsic, extrinsic and ER-mediated apoptotic induction by hyperthermia in an in vitro model of human malignant melanoma and furthermore, to evaluate its therapeutic effectiveness in an adjuvant therapeutic setting characterized by combinational treatments with non-targeted (Dacarbazine & Temozolomide) and targeted (Dabrafenib & Vemurafenib) drugs. Overall, our data showed that both low (43 °C) and high (45 °C) hyperthermic exposures were capable of inducing cell death by activating all apoptotic pathways but in a rather distinct manner. More specifically, low hyperthermia induced extrinsic and intrinsic apoptotic pathways both of which activated caspase 6 only as opposed to high hyperthermia which was mediated by the combined effects of caspases 3, 7 and 6. Furthermore, significant involvement of the ER was evident (under both hyperthermic conditions) suggesting its role in regulating apoptosis via activation of CHOP. Our data revealed that while low hyperthermia activated IRE-1 and ATF6 only, high hyperthermia induced activation of PERK as well suggesting that ultimately these ER stress sensors can lead to the induction of CHOP via different pathways of transmitted signals. Finally, combinational treatment protocols revealed an effect of hyperthermia in potentiating the therapeutic effectiveness of non-targeted as well as targeted drugs utilized in the clinical setting. Overall, our findings support evidence into hyperthermia's therapeutic potential in treating human malignant melanoma by elucidating the underlying mechanisms of its complex apoptotic induction.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Apoptosis/efectos de los fármacos , Hipertermia Inducida , Melanoma/terapia , Neoplasias Cutáneas/terapia , Línea Celular Tumoral , Terapia Combinada/métodos , Humanos , Melanoma/patología , Neoplasias Cutáneas/patología , Resultado del Tratamiento
6.
Nat Commun ; 7: 13251, 2016 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-27827361

RESUMEN

Multipartite entangled states are a fundamental resource for a wide range of quantum information processing tasks. In particular, in quantum networks, it is essential for the parties involved to be able to verify if entanglement is present before they carry out a given distributed task. Here we design and experimentally demonstrate a protocol that allows any party in a network to check if a source is distributing a genuinely multipartite entangled state, even in the presence of untrusted parties. The protocol remains secure against dishonest behaviour of the source and other parties, including the use of system imperfections to their advantage. We demonstrate the verification protocol in a three- and four-party setting using polarization-entangled photons, highlighting its potential for realistic photonic quantum communication and networking applications.


Asunto(s)
Diseño Asistido por Computadora , Procesamiento Automatizado de Datos/métodos , Fotones , Teoría Cuántica , Algoritmos , Humanos , Modelos Teóricos
7.
Psychiatriki ; 27(1): 17-26, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27110879

RESUMEN

Αlcohol abuse/dependence seriously affects quality of life (QoL). The AlQoL-9 scale, derived from the generic instrument SF-36, is the only instrument in the international literature which is specific as a measure of QoL for alcohol-dependent patients. It can provide health carers with valuable information regarding the needs of alcoholic individuals and the effects of therapeutic interventions. The aim of this study was to assess the psychometric properties of the Greek version of AlQoL-9 taking as a basis the research on the original French and English versions. A sample of 170 participants (118 males, 52 females) aged 24-74 years (mean age=48.2 years, SD=9.6) recruited from inpatient and outpatient detoxification units in different regions of Greece completed the AlQoL-9 questionnaire and the World Health Organization Quality of Life Assessment - short version (WHOQOL-BREF). The internal structure of the AlQoL-9 questionnaire was examined using confirmatory factor analysis (CFA). The associations of AlQoL-9 with sociodemographic and clinical variables were examined. The correlation coefficients between AlQoL-9 and scores on the domains of the WHOQOL-BREF questionnaire were computed as an indication of convergent validity. The average inter-item correlation between the AlQoL-9 items was 0.403. CFA supported a single factor underlying the AlQoL-9 items. Cronbach's alpha for the Greek version of the scale showed high internal consistency, 0.837, and could not be improved by omitting any item. The AlQoL-9 score showed significant associations with gender (mean 29.2, SD=6.2 for males; mean 26.1, SD=7.2 for females: p=0.004) and with comorbidity (mean 25.7, SD=7.8 with comorbidity, mean 29.5, SD=5.8 without: p=0.001). The AlQoL-9 score was significantly correlated (p<0.001) with all scores of the WHOQOL-BREF, most strongly with the WHOQOL domains of physical health (Pearson's r=0.720) and psychological health (r=0.693) and less so with social relationships (0.481), environment (0.411), and the single-item measures of overall health (0.554) and overall quality of life (0.522). The present study demonstrated that the Greek version of the AlQoL-9 constitutes a valid and reliable single-factor research instrument for evaluating quality of life among alcohol-dependent individuals. It is recommended to be used in combination with a generic QoL instrument e.g. the WHOQOL-BREF. It is suitable for clinical everyday practice to monitor possible patient QoL changes, as well as in large scale studies investigating QoL in the relevant population.


Asunto(s)
Alcoholismo/psicología , Alcoholismo/rehabilitación , Comparación Transcultural , Psicometría/estadística & datos numéricos , Calidad de Vida/psicología , Encuestas y Cuestionarios , Adulto , Anciano , Femenino , Grecia , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Traducción
8.
Environ Sci Pollut Res Int ; 23(9): 8890-901, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26810792

RESUMEN

Controlled field experiments were carried out for monitoring the emissions of three plastic commercial household waste bins, which were adapted for studying the effect of aeration process in the evolved volatiles, during house storing of green food waste for 2 weeks, prior to collection. Three experimental scenarios were examined based on no aeration ("NA," closed commercial waste bin), diffusion-based aeration ("DA," closed commercial waste bin with tiny holes), and enforced aeration ("EA," closed commercial waste bin with tiny holes and enforced aeration). The monitoring of volatile organic compounds (VOCs) emitted from organic household kitchen waste was performed using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) analysis. Portable sensors were also used for monitoring selected gases and parameters of environmental, bioprocess, and health interest (e.g., CO2, O2, H2S, CH4, NH3, % RH, waste temperatures). VOC emissions are strongly dependent on the waste material. The most frequent VOCs identified over the storing waste, showing over 50 % appearance in all examined samples, were terpenes (e.g., di-limonene, beta-myrcene, delta-3-carene, alpha-pinene, alpha-terpinolene, linalool, etc.), sulfides (dimethyl disulfide), aromatics (benzene, 1-methyl-2-(2-propenyl)), alkanes (e.g., decane, dodecane), ketones (2-propanone), esters (e.g., acetic acid ethyl ester, acetic acid methyl ester), and alcohols (e.g., 3-cyclohexen-1-ol, 4-methyl-1-(1-methylethyl)). The prominent role of terpenes in the "pre-compost" odor and especially that of di-limonene was highlighted. In all examined scenarios, the emitted volatiles were increased at raised temperatures and later decreased in time. Aeration of waste bins slightly affected the volatilization process resulting in higher profiles of VOCs; uniformity in the composition of VOCs was also noted. Slight modifications of commercial waste bins may favor the initiation of home composting.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Residuos de Alimentos , Odorantes/análisis , Compuestos Orgánicos Volátiles/análisis , Residuos/análisis , Monoterpenos Acíclicos , Monoterpenos Bicíclicos , Alimentos , Cromatografía de Gases y Espectrometría de Masas , Cetonas/análisis , Monoterpenos/análisis , Suelo/química , Microextracción en Fase Sólida , Volatilización
9.
Anal Chem ; 86(8): 3887-94, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24697615

RESUMEN

The design, development, and validation of a dynamic vapor generator are presented. The generator simulates human scent (odor) emissions from trapped victims in the voids of collapsed buildings. The validation of the device was carried out using a reference detector: a quadrupole mass spectrometer equipped with a pulsed sampling (PS-MS) system. A series of experiments were conducted for evaluating the simulator's performance, defining types and weights of different factors, and proposing further optimization of the device. The developed device enabled the production of stable and transient odor profiles in a controllable and reproducible way (relative standard deviation, RSD < 11%) at ppbv to low ppmv concentrations and allowed emission durations up to 30 min. Moreover, the factors affecting its optimum performance (i.e., evaporation chamber temperature, air flow rate through the mixing chamber, air flow rate through the evaporation chamber, and type of compound) were evaluated through an analysis of variance (ANOVA) tool revealing the next steps toward optimizing the generator. The developed simulator, potentially, can also serve the need for calibrating and evaluating the performance of analytical devices (e.g., gas chromatographers, ion mobility spectrometers, mass spectrometers, sensors, e-noses) in the field. Furthermore, it can contribute in better training of urban search and rescue (USaR) canines.


Asunto(s)
Odorantes/análisis , Trabajo de Rescate , Movimientos del Aire , Animales , Perros , Humanos , Estándares de Referencia , Reproducibilidad de los Resultados , Orina/química
10.
Environ Sci Pollut Res Int ; 21(2): 891-900, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23832773

RESUMEN

Fires are becoming more violent and frequent resulting in major economic losses and long-lasting effects on communities and ecosystems; thus, efficient fire monitoring is becoming a necessity. A novel triple multi-sensor approach was developed for monitoring and studying the burning of dry forest fuel in an open field scheduled experiment; chemical, optical, and acoustical sensors were combined to record the fire spread. The results of this integrated field campaign for real-time monitoring of the fire event are presented and discussed. Chemical analysis, despite its limitations, corresponded to the burning process with a minor time delay. Nevertheless, the evolution profile of CO2, CO, NO, and O2 were detected and monitored. The chemical monitoring of smoke components enabled the observing of the different fire phases (flaming, smoldering) based on the emissions identified in each phase. The analysis of fire acoustical signals presented accurate and timely response to the fire event. In the same content, the use of a thermographic camera, for monitoring the biomass burning, was also considerable (both profiles of the intensities of average gray and red component greater than 230) and presented similar promising potentials to audio results. Further work is needed towards integrating sensors signals for automation purposes leading to potential applications in real situations.


Asunto(s)
Monitoreo del Ambiente/instrumentación , Incendios , Humo/análisis , Contaminantes Atmosféricos/análisis , Biomasa , Ecosistema , Monitoreo del Ambiente/métodos , Agricultura Forestal/instrumentación , Agricultura Forestal/métodos , Árboles , Grabación en Video
11.
Andrologia ; 44(5): 337-42, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22946848

RESUMEN

A series of studies aiming at introducing an effective treatment for idiopathic oligozoospermia was conducted in a step-wise fashion spanning over a 20-year period. The concept was that co-administration of an accessory gland-stimulating androgen, testosterone undecanoate (40 mg t.i.d.) and the FSH raising anti-oestrogen tamoxifen citrate (10 mg b.i.d.) may improve sperm parameters. A prerequisite for such an effect was the demonstration that testosterone undecanoate had no suppressing action on pituitary-testicular axis. In this context, initial studies demonstrated no change in basal or stimulated gonadotrophin and testosterone secretion in short- or long-term protocols. Two subsequent trials with this combination showed a marked improvement of sperm parameters and pregnancy incidence, with a seasonal variation noted in response to treatment, this being higher during the cold seasons of autumn and winter. Regarding the mechanism of testosterone undecanoate's action, a recent study from our unit showed that its administration resulted in a marked rise of serum DHT levels. Because this steroid is an epididymal function promoter, it appears that its contribution in the combination is mediated mainly through its DHT raising effect. By and large, this empiric approach for the treatment of idiopathic oligozoospermia was satisfactorily documented after a 20-year investigative saga.


Asunto(s)
Oligospermia/tratamiento farmacológico , Tamoxifeno/uso terapéutico , Testosterona/análogos & derivados , Clima , Antagonistas de Estrógenos/uso terapéutico , Femenino , Humanos , Células Intersticiales del Testículo/efectos de los fármacos , Masculino , Hipófisis/efectos de los fármacos , Embarazo , Índice de Embarazo , Recuento de Espermatozoides , Testosterona/uso terapéutico
12.
Curr Mol Med ; 12(6): 681-97, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22292436

RESUMEN

Oxidative stress is caused by an imbalance between the production of reactive species of oxygen and nitrogen (RS) and the ability to either detoxify the reactive intermediates produced or repair the resulting damage. Ultimately, oxidative stress conveys the alteration in cellular function caused by the reaction of RS with cellular constituents. Oxidative stress has been extensively reported to participate in the progression of a variety of human diseases including cancer, neurodegenerative disorders and diabetes. Oxidation of proteins is thought to be one of the major mechanisms by which oxidative stress is integrated into cellular signal transduction pathways. Thus, recent research efforts have been aimed to identify the role of specific oxidative protein modifications in the signal transduction events mediating the etiology of human diseases progression. The identification of these oxidative modifications has also raised the possibility of using this knowledge to develop new methods to diagnose diseases before they are clinically evident. In this work, we summarize the mechanisms by which RS generate distinct oxidative modifications. Furthermore, we also review the potential of these oxidative modifications to be used as early biomarkers of human disease.


Asunto(s)
Estrés Oxidativo , Proteínas/metabolismo , Animales , Biomarcadores/metabolismo , Diabetes Mellitus/metabolismo , Humanos , Neoplasias/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Oxidación-Reducción , Carbonilación Proteica , Especies de Nitrógeno Reactivo/metabolismo , Especies Reactivas de Oxígeno/metabolismo
13.
Curr Mol Med ; 12(6): 698-703, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22292437

RESUMEN

Oral cancer accounts for 2-3% of all malignancies and according to the World Health Organization (WHO) is the fifth most common cancer worldwide. On the other hand, "oxidative stress" implies a cellular state whereby reactive oxygen species (ROS) production exceeds its metabolism resulting in excessive ROS accumulation and overwhelmed cellular defenses. Such a state has been shown to be involved in the multistage process of human carcinogenesis (including oral cancer) via many different mechanisms. Amongst them are ROS-induced oxidative modifications on major cellular macromolecules like DNA, proteins and lipids with the resulting byproducts being involved in the pathophysiology of human oral malignant and pre-malignant lesions. Throughout this manuscript, we review the current state of knowledge on the role of these oxidative-modified cellular byproducts in serving as reliable biomarkers for oral cancer detection, prognosis and diagnosis.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Transformación Celular Neoplásica/metabolismo , Neoplasias de la Boca/metabolismo , Estrés Oxidativo , Daño del ADN , Humanos , Peroxidación de Lípido , Neoplasias de la Boca/etiología , Proteínas/metabolismo , Especies Reactivas de Oxígeno/metabolismo
14.
Int J Syst Evol Microbiol ; 60(Pt 6): 1432-1436, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19671720

RESUMEN

A novel halophilic bacterium, designated strain MSS4(T), was isolated from the solar salterns of Mesolongi, Greece. The micro-organism, a motile, Gram-stain-positive, aerobic rod, proliferated at salinities of 1.0-4.0 M NaCl, with optimal growth at 2.5 M NaCl. Endospores were not observed. Strain MSS4(T) showed optimal growth at 37 degrees C and pH 8.0. The G+C content of its DNA was 47.2 mol%. The polar lipid pattern of strain MSS4(T) consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidic acid and phosphatidylethanolamine. It possessed anteiso-C(15 : 0), C(18 : 0), C(16 : 0) and anteiso-C(17 : 0) as the major fatty acids (altogether representing 84.7 % of the total). The predominant isoprenoid quinone was MK-7. The cell-wall peptidoglycan contained meso-diaminopimelic acid. 16S rRNA gene sequence analysis showed that the new isolate has 96.1 % similarity to Bacillus qingdaonensis CM1(T) and Bacillus aidingensis 17-5(T), 95.5 % to Bacillus salarius BH169(T) and lower similarity to other Bacillus species. These results justify the assignment of strain MSS4(T) to a novel species within the genus Bacillus, for which the name Bacillus halochares sp. nov. is proposed. The type strain is MSS4(T) (=LMG 24571(T) =DSM 21373(T)).


Asunto(s)
Bacillus/genética , Bacillus/clasificación , Bacillus/crecimiento & desarrollo , Bacillus/aislamiento & purificación , Composición de Base , ADN Bacteriano/genética , ADN Bacteriano/metabolismo , Grecia , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Monosacáridos/metabolismo , Nitratos/metabolismo , Filogenia , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Agua de Mar/microbiología , Esporas Bacterianas/fisiología , Ureasa/metabolismo
15.
Andrologia ; 41(2): 118-24, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19260849

RESUMEN

This study attempted to investigate the presence of seasonal variations in sperm parameters and to evaluate the season's impact on the response to treatment in men with idiopathic oligozoospermia (IO). To this end, a retrospective analysis of the records of 294 men, who participated in a controlled study, was performed. This sample included IO men (n = 106) treated with tamoxifen citrate (10 mg b.i.d.) and testosterone undecanoate (40 mg t.i.d.) or placebo (n = 106) and normozoospermic men (n = 82) serving as controls. Outcome measures included sperm parameters, functional sperm fraction (FSF) and incidence of pregnancy. Analysis showed a raised frequency of high FSF values and increased area under the response curve (AURC) for FSF mean during autumn-winter seasons in patients on active treatment compared with those in placebo (P < 0.05-P < 0.04). Moreover, receiver operation characteristics (ROC) curves for a >100% FSF rise significantly discriminated autumn-winter from other seasons (P < 0.001, all), whereas active treatment showed higher than placebo FSF values particularly during autumn and winter (P < 0.001, all). The pregnancy incidence was higher in the autumn in all groups. It is concluded that FSF values showed a better response to active treatment during autumn and winter, indicating that commencement of empirical treatment at this time in IO men may stand a better chance to succeed.


Asunto(s)
Oligospermia/tratamiento farmacológico , Oligospermia/fisiopatología , Estaciones del Año , Espermatozoides/fisiología , Femenino , Humanos , Masculino , Embarazo , Índice de Embarazo , Curva ROC , Estudios Retrospectivos , Tamoxifeno/uso terapéutico , Testosterona/análogos & derivados , Testosterona/uso terapéutico
16.
Arch Physiol Biochem ; 113(4-5): 234-58, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18158646

RESUMEN

Reduced glutathione (L-gamma-glutamyl-L-cysteinyl-glycine, GSH) is the prevalent low-molecular-weight thiol in mammalian cells. It is formed in a two-step enzymatic process including, first, the formation of gamma-glutamylcysteine from glutamate and cysteine, by the activity of the gamma-glutamylcysteine synthetase; and second, the formation of GSH by the activity of GSH synthetase which uses gamma-glutamylcysteine and glycine as substrates. While its synthesis and metabolism occur intracellularly, its catabolism occurs extracellularly by a series of enzymatic and plasma membrane transport steps. Glutathione metabolism and transport participates in many cellular reactions including: antioxidant defense of the cell, drug detoxification and cell signaling (involved in the regulation of gene expression, apoptosis and cell proliferation). Alterations in its concentration have also been demonstrated to be a common feature of many pathological conditions including diabetes, cancer, AIDS, neurodegenerative and liver diseases. Additionally, GSH catabolism has been recently reported to modulate redox-sensitive components of signal transduction cascades. In this manuscript, we review the current state of knowledge on the role of GSH in the pathogenesis of human diseases with the aim to underscore its relevance in translational research for future therapeutic treatment design.


Asunto(s)
Diabetes Mellitus/fisiopatología , Glutatión/metabolismo , Enfermedades Pulmonares/fisiopatología , Neoplasias/fisiopatología , Diabetes Mellitus/metabolismo , Quimioterapia/métodos , Glutatión/biosíntesis , Glutatión/deficiencia , Humanos , Enfermedades Pulmonares/metabolismo , Neoplasias/metabolismo , Estrés Oxidativo/efectos de los fármacos
17.
Curr Med Chem ; 14(24): 2590-6, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17979712

RESUMEN

Over 95% of the oxygen we metabolize undergoes a four-electron reduction to produce two molecules of water. Whenever electrons escape from the mitochondrial electron-transport chain and pass directly onto oxygen, oxidants that can cause cytotoxicity are generated. The lung being constantly exposed to atmospheric oxygen is more susceptible to oxidant-induced cellular damage. For instance, increased generation of oxidants is implicated in many pulmonary pathological conditions including emphysema, adult respiratory distress syndrome, idiopathic pulmonary fibrosis and asthma. Sulfur is an essential major inorganic element with a recently described protective cellular role. One of its many biologically important functions is the formation of disulfide bridges between two cysteine molecules thus stabilizing protein conformation. Also, it provides the site for attachment and transfer of 1-C methyl groups via formation of S-adenosylmethionine, and most importantly it is an essential constituent of the antioxidant tripeptide, glutathione, and vitamins like thiamin and biotin. However, its protective role emanates from its antioxidant properties in the context of sulfur-containing compounds (S-adenosylmethionine, cysteine, taurine, glutathione etc) that are known to act in protecting against oxidant-induced lung disease. The efficacy of these sulfur-containing compounds in scavenging oxidants directly or indirectly and consequently protecting against lung diseases is discussed herein.


Asunto(s)
Enfermedades Pulmonares/tratamiento farmacológico , Enfermedades Pulmonares/metabolismo , Oxidantes/metabolismo , Compuestos de Azufre/uso terapéutico , Animales , Humanos , Compuestos de Azufre/química , Compuestos de Azufre/metabolismo
18.
Anal Chim Acta ; 573-574: 439-44, 2006 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-17723558

RESUMEN

In this work a new method called TG-bridge/mass spectrometry is presented, for the on-line monitoring of the pine needles combustion emissions in a common lab furnace. The TG-bridge (thermogravimetry-bridge) system has been developed in-house as a TG-MS (thermogravimetry-mass spectrometry) interface, for TG-MS analysis. In this work, TG-bridge was used for directly sampling of the combustion emissions from the inside of the furnace and transferring them into the mass spectrometer (MS), without disturbing the sub-pressure conditions inside the MS ion source. The effect of Fire-Trol 931 (a long-term fire retardant) on the emissions, produced during the combustion of pine needles, is tested in the lab for future application in the field. It was shown that in treated samples, increased evolution of ammonia and aromatic compounds took place, compared to untreated samples. Maximum concentrations of specific compounds, such as benzene and toluene, evolved during the combustion experiments in the furnace, were determined.

19.
J Chromatogr B Analyt Technol Biomed Life Sci ; 822(1-2): 112-7, 2005 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-15996539

RESUMEN

A preliminary investigation on the possibility of using volatile organic compounds (VOCs) determination of expired air, blood and urine, for the early location of entrapped people in earthquakes, has been carried out. A group of 15 healthy subjects has been sampled. The identification of a common "core" of substances might provide indications of human presence that can be used for the development of a real time field analytical method for the on site detection of entrapped people. Expired air samples have been analyzed by thermal desorption GC/MS and VOCs from blood and urine by headspace SPME-GC/MS. Acetone was the only compound found common in all three matrices. Isoprene was found in both expired air and blood samples. Acetone and isoprene along with a number of saturated hydrocarbons were among the major constituents identified in expired air analysis. Various ketones (2-pentanone, 4-heptanone, 2-butanone) were also determined over urine specimens. Using the techniques and methods of field analytical chemistry and technology appears to be the proper approach for applying the results of the present study in real situations.


Asunto(s)
Pruebas Respiratorias , Desastres , Compuestos Orgánicos/análisis , Trabajo de Rescate/métodos , Respiración , Acetona/análisis , Adulto , Pruebas Respiratorias/métodos , Butadienos/análisis , Femenino , Cromatografía de Gases y Espectrometría de Masas , Hemiterpenos/análisis , Humanos , Cetonas/análisis , Masculino , Compuestos Orgánicos/sangre , Compuestos Orgánicos/orina , Pentanos/análisis , Volatilización
20.
Reprod Domest Anim ; 38(5): 367-72, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12950686

RESUMEN

The development of competitive enzyme immunoassays for ovine plasma LH (oLH) and FSH (oFSH) is described. Standards and plasma samples were preincubated with diluted antiserum to oLH or oFSH and the reacted solution (100 micro l per well) was transferred to plates previously coated with oLH or oFSH, respectively. The second antibody used was anti-rabbit IgG horseradish peroxidase. The measuring range was 0.39-50 ng/ml for each hormone and the 50% relative binding sensitivity was 9 ng/ml for oLH. The respective value for oFSH was 3.5 or 34 ng/ml with different hormone and antibody preparations used for the assay. The enzyme immunoassays were used to determine oLH and oFSH levels in plasma from ewes of two breeds during the oestrous cycle. The assays detected the first FSH surge coincident with the LH surge, the second FSH surge about 24 h later and the periodic fluctuations of FSH concentrations during the luteal phase of the oestrous cycle. These enzyme immunoassays are an efficient and economic alternative to the established radioimmunoassays (RIA) for oLH and oFSH.


Asunto(s)
Estro , Hormona Folículo Estimulante/sangre , Hormona Luteinizante/sangre , Ovinos/sangre , Animales , Femenino , Técnicas para Inmunoenzimas/veterinaria
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