Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Sci Total Environ ; 905: 167242, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-37742982

RESUMEN

The 50th anniversary of Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) will be observed in 2024. ICP-OES was first commercially available in 1974, and since then, it has become one of the most widely used analytical techniques in the world. ICP-OES is a powerful tool for the determination of trace and ultratrace elemental concentrations in a wide variety of samples specifically for multielement analysis. It is used in a wide range of applications, including environmental monitoring, food analysis, and medical diagnostics. This review aims to explore recent applications of ICP-OES in areas such as food analysis, microplastics, materials, dietary supplements, human tissue, and bodily fluids. The utilization of ICP-OES in these fields has ignited the interest of prospective ICP-OES users and inspired current practitioners, as the 50th anniversary approaches, it is of value of providing an updated review. It is important to note that this work does not seek to encompass a comprehensive review of ICP-OES, given the vast number of published results in this field. Undertaking such a comprehensive task would be a daunting challenge. Consequently, an overview of the ICP-OES instrumental technique is provided, followed by a highlighting of recent significant applications in the aforementioned fields.


Asunto(s)
Oligoelementos , Humanos , Oligoelementos/análisis , Plásticos , Estudios Prospectivos , Análisis Espectral
2.
BMJ Case Rep ; 16(7)2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37402587

RESUMEN

We present an unusual case of ruptured subclavian artery pseudoaneurysm following hydrotherapy and shoulder massage session on a background of clavicle non-union.Following a clavicle fracture 16 years ago, which was managed conservatively, a woman in her 30s presents over a decade later with a ruptured subclavian artery pseudoaneurysm.The original midshaft clavicle fracture was sustained 16 years ago. Conservative management was agreed, and she was discharged. Six years ago, she developed a small subclavian artery pseudoaneurysm which was kept under surveillance for 12 months with no active intervention required.Over the following years, she continued to have intermittent shoulder girdle discomfort and neuropathic symptoms. On this presentation, after a sports massage, she presented with rapid-onset supraclavicular and axillary swelling. This was diagnosed as a ruptured subclavian artery pseudoaneurysm and was treated with emergency radiological-guided stenting and subsequent internal fixation of the clavicle non-union.The patient then attended regular orthopaedic and vascular follow-up to ensure her clavicle fracture unites and the graft remains patent.We discuss the case presentation and management of this unusual injury.


Asunto(s)
Aneurisma Falso , Fracturas Óseas , Femenino , Humanos , Hombro , Clavícula/lesiones , Arteria Subclavia/diagnóstico por imagen , Arteria Subclavia/cirugía , Aneurisma Falso/diagnóstico por imagen , Aneurisma Falso/etiología , Aneurisma Falso/terapia , Fracturas Óseas/complicaciones , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/terapia , Fijación Interna de Fracturas , Masaje
3.
Bioelectromagnetics ; 44(1-2): 5-16, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36786477

RESUMEN

Previous research has shown that virus infectivity can be dramatically reduced by radio frequency exposure in the gigahertz (GHz) frequency range. Given the worldwide SARS-CoV-2 pandemic, which has caused over 1 million deaths and has had a profound global economic impact, there is a need for a noninvasive technology that can reduce the transmission of virus among humans. RF is a potential wide area-of-effect viral decontamination technology that could be used in hospital rooms where patients are expelling virus, in grocery and convenience stores where local populations mix, and in first responder settings where rapid medical response spans many potentially infected locations within hours. In this study, we used bovine coronavirus (BCoV) as a surrogate of SARS-CoV-2 and exposed it to high peak power microwave (HPPM) pulses at four narrowband frequencies: 2.8, 5.6, 8.5, and 9.3 GHz. Exposures consisted of 2 µs pulses delivered at 500 Hz, with pulse counts varied by decades between 1 and 10,000. The peak field intensities (i.e. the instantaneous power density of each pulse) ranged between 0.6 and 6.5 MW/m2 , depending on the microwave frequency. The HPPM exposures were delivered to plastic coverslips containing BCoV dried on the surface. Hemagglutination (HA) and cytopathic effect analyses were performed 6 days after inoculation of host cells to assess viral infectivity. No change in viral infectivity was seen with increasing dose (pulse number) across the tested frequencies. Under all conditions tested, exposure did not reduce infectivity more than 1.0 log10. For the conditions studied, high peak power pulsed RF exposures in the 2-10 GHz range appear ineffective as a virucidal approach for hard surface decontamination. © 2023 Bioelectromagnetics Society.


Asunto(s)
COVID-19 , Inactivación de Virus , Animales , Bovinos , Humanos , SARS-CoV-2 , Microondas
4.
Appl Biochem Biotechnol ; 195(10): 5966-5979, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36729297

RESUMEN

BACKGROUND: Some herbal natural products play an important role in protecting organisms from the toxic effect of some xenobiotics. The present study was designed to evaluate the potential therapeutic effects of Ottelione A (OTTE) against carbon tetrachloride(CCl4)-induced toxicity in mice. METHODS: Adult male Swiss albino mice were divided into six groups: group I was used as a normal control received olive oil; group II received DMSO; group III received OTTE; group IV received CCl4 in olive oil, (injected i.p) 3 times/week for 6 weeks; group V received the same CCl4 regimen as group IV followed by OTTE injected for 15 days, and group VI first received OTTE injected for 15 days followed by the same CCl4 regimen as group IV. Some biochemical and histological parameters were investigated. RESULTS: Our results showed that the administration of CCl4 caused hepatotoxicity, as monitored by the significant increase in biochemical parameters concerning the olive oil group. Treatment with OTTE appeare d to be effective against hepatotoxic and liver changes induced by CCl4, as evidenced by the improvement of the same parameters. CONCLUSION: Ottelione A (OTTE) has good antioxidant and therapeutic properties, which can help in preventing CCl4-induced hepatotoxicity in both pre-treatment and post-treatment modes.


Asunto(s)
Tetracloruro de Carbono , Enfermedad Hepática Inducida por Sustancias y Drogas , Ratones , Masculino , Animales , Tetracloruro de Carbono/toxicidad , Tetracloruro de Carbono/metabolismo , Aceite de Oliva/farmacología , Aceite de Oliva/metabolismo , Extractos Vegetales/química , Antioxidantes/farmacología , Hígado/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Estrés Oxidativo
5.
Br J Nutr ; 128(4): 653-658, 2022 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-34511161

RESUMEN

Tea contains polyphenols such as flavonoids, anthocyanidins, flavanols and phenolic acids which in laboratory studies have reported to promote antioxidant enzyme formation, reduces excess inflammation, slow cancer cell proliferation and promote apoptosis. Evidence from epidemiological studies on the effect of tea consumption on prostate cancer (CaP) incidence has been conflicting. We analysed data from 25 097 men within the intervention arm of the 155 000 participant Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. Histologically confirmed cases of prostate cancer were reported in 3088 men (12·3 %) during the median 11·5 year follow-up. Tea consumption was assessed with a FFQ. Baseline characteristics were compared between groups using χ2 and Kruskal-Wallis tests. Cox regression models were used to assess associations between tea intake and CaP incidence. There was no statistical difference between the risk of CaP between men who never drank tea to those who drank tea at any quantity. Amongst tea drinkers, those in the highest third of consumption group had a small but significantly lower risk compared with those in the lowest third (11·2 % v. 13·2 % hazard ratio 1·16; (95 % CI 1·05, 1·29), P = 0·004). This pattern persisted with adjustments for demographics and lifestyle. In conclusion, among tea drinkers, there was a small positive association between drinking tea and a reduced risk of prostate cancer. It does not support starting to drink tea, if men previously did not, to reduce the risk. Further research is needed to establish whether tea is justified for future prospective nutritional intervention studies investigating CaP prevention.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Ováricas , Neoplasias de la Próstata , Masculino , Femenino , Humanos , Próstata/patología , , Detección Precoz del Cáncer , Neoplasias de la Próstata/prevención & control , Polifenoles , Pulmón , Factores de Riesgo
6.
Regul Toxicol Pharmacol ; 107: 104396, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31128168

RESUMEN

Large data sharing projects amongst the pharmaceutical industry have the potential to generate new insights using data on a scale that has not been previously available. A retrospective analysis of the preclinical toxicology data collected as part of the eTOX project was conducted with the aim to provide background rates and treatment-related value analysis on both clinical pathology and histopathology datasets. Incorporated into this analysis was an extensive data consolidation task to standardise all data. Reference intervals for common clinical pathology parameters in rat and dog were generated, alongside background histopathology incidence rates in the liver, heart and kidney. Systematically applied decision thresholds allowed consistent relabelling of data points considered anomalous, and maximum fold change estimates. Relabelling of anomalous data points was conducted for the histopathology data using a Bayesian model to identify dose-dependent increases in pathologies. The results of this study allow: newly generated data to be analysed using the same methodology, rates and distributions to be used when building predictive dose-response models, and the possibility to correlate clinical pathology findings with concurrent histopathology findings. In the first half of this paper we discuss data curation, in the second half we report on the analytical methods and results.


Asunto(s)
Bases de Datos Factuales , Evaluación Preclínica de Medicamentos , Patología Clínica , Animales , Industria Farmacéutica , Difusión de la Información , Pruebas de Toxicidad
7.
Breast Cancer Res Treat ; 171(1): 103-110, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29736742

RESUMEN

PURPOSE: Nail damage is common amongst patients receiving chemotherapy causing disfigurement and pain. This investigation evaluated whether a topical balm containing steam-extracted, bioactive polyphenolic-rich herbal oils blended with organic waxes could protect the nails via their reported anti-inflammatory, analgesic, anti-oxidant and anti-microbial properties. METHODS: 60 patients (23M, 37F) were randomised to apply (2-3/day) either the plant balm (PB) or a petroleum control (PC) to their nail beds. Demographics, type and number of chemotherapy cycles did not differ between the two groups, recruited between Sept 2015 and Sept 2016. An unpaired t test was used to test the differences in symptoms and physical nail damage between the two groups. RESULTS: Symptom scores recorded with the dermatology life quality questionnaire (DLQQ) were significantly better, between the start and end of chemotherapy, in the group applying the PB versus PC. Likewise, the mean fall in nail damage, scored with the Nail Psoriasis Index by the supervising physician, was also significantly different. CONCLUSION: The polyphenolic-rich essential oils and plant-based waxes in this nail bed balm profoundly reduced chemotherapy-related nail damage and improved nail-related quality of life, compared to a control. A further analysis is planned combining this balm with nail bed cooling.


Asunto(s)
Antineoplásicos/efectos adversos , Onicólisis/etiología , Onicólisis/terapia , Aceites de Plantas/administración & dosificación , Polifenoles/administración & dosificación , Femenino , Humanos , Masculino , Onicólisis/diagnóstico , Aceites de Plantas/química , Polifenoles/química , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Reino Unido
8.
Artículo en Inglés | MEDLINE | ID: mdl-29133380

RESUMEN

BACKGROUND: Obstructive sleep apnea (OSA) is associated with atrial remodeling, atrial fibrillation (AF), and increased incidence of arrhythmia recurrence after pulmonary vein (PV) isolation. We aimed to characterize the atrial substrate, including AF triggers in patients with paroxysmal AF and OSA. METHODS AND RESULTS: In 86 patients with paroxysmal AF (43 with ≥moderate OSA [apnea-hypopnea index ≥15] and 43 without OSA [apnea-hypopnea index <5]), right atrial and left atrial voltage distribution, conduction velocities, and electrogram characteristics were analyzed during atrial pacing. AF triggers were examined before and after PV isolation and targeted for ablation. Patients with OSA had lower atrial voltage amplitude (right atrial, P=0.0005; left atrial, P=0.0001), slower conduction velocities (right atrial, P=0.02; left atrial, P=0.0002), and higher prevalence of electrogram fractionation (P=0.0001). The areas of atrial abnormality were consistent among patients, most commonly involving the left atrial septum (32/43; 74.4%). At baseline, the PVs were the most frequent triggers for AF in both groups; however, after PV isolation patients with OSA had increased incidence of additional extra-PV triggers (41.8% versus 11.6%; P=0.003). The 1-year arrhythmia-free survival was similar between patients with and without OSA (83.7% and 81.4%, respectively; P=0.59). In comparison, control patients with paroxysmal AF and OSA who underwent PV isolation alone without ablation on extra-PV triggers had increased risk of arrhythmia recurrence (83.7% versus 64.0%; P=0.003). CONCLUSIONS: OSA is associated with structural and functional atrial remodeling and increased incidence of extra-PV triggers. Elimination of these triggers resulted in improved arrhythmia-free survival.


Asunto(s)
Fibrilación Atrial/etiología , Venas Pulmonares/fisiopatología , Apnea Obstructiva del Sueño/complicaciones , Potenciales de Acción , Adulto , Anciano , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Fibrilación Atrial/cirugía , Remodelación Atrial , Ablación por Catéter , Supervivencia sin Enfermedad , Técnicas Electrofisiológicas Cardíacas , Femenino , Frecuencia Cardíaca , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Venas Pulmonares/cirugía , Recurrencia , Factores de Riesgo , Índice de Severidad de la Enfermedad , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/fisiopatología , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
9.
Sleep Med Clin ; 11(2): 241-55, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27236060

RESUMEN

Analysis of large-volume data holds promise for improving the application of precision medicine to sleep, including improving identification of patient subgroups who may benefit from alternative therapies. Big data used within the health care system also promises to facilitate end-to-end screening, diagnosis, and management of sleep disorders; improve the recognition of differences in presentation and susceptibility to sleep apnea; and lead to improved management and outcomes. To meet the vision of personalized, precision therapeutics and diagnostics and improving the efficiency and quality of sleep medicine will require ongoing efforts, investments, and change in our current medical and research cultures.


Asunto(s)
Intercambio de Información en Salud , Síndromes de la Apnea del Sueño/terapia , Humanos , Síndromes de la Apnea del Sueño/diagnóstico
10.
J Biomed Opt ; 18(11): 110501, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24193944

RESUMEN

We studied the efficacy of mild hyperthermia as a protective measure against subsequent laser-induced thermal damage. Using a well established in vitro retinal model for laser bioeffects, consisting of an artificially pigmented human retinal pigment epithelial (RPE) cell culture (hTERT-RPE1), we found both protection and sensitization to laser damage that depended upon the location of pigment granules during the hyperthermia preconditioning (PC). Photothermal challenge of cell monolayers consisted of 16 independent replicate exposures of 65 W/cm2 at 514 nm and post laser damage was assessed using fluorescence indicator dyes. Untreated cells had 44% damage, but when melanosome particles (MPs) were intracellular or extracellular during the hyperthermia treatment, laser-induced cell damage occurred 94% or 25% of the time, respectively. Using a recently published method called microthermography, we found that the hyperthermia pretreatment did not alter the threshold temperature for cell death, indicating an alteration in absorption or localization of heat as the mechanism for sensitization and protection. Raman microspectroscopy revealed significant chemical changes in MPs when they were preconditioned within the cytoplasm of cells. Our results suggest intracellular pigment granules undergo chemical modifications during mild hyperthermia that can profoundly affect absorption or heat dissipation.


Asunto(s)
Células Epiteliales/citología , Células Epiteliales/fisiología , Hipertermia Inducida/métodos , Células Cultivadas , Células Epiteliales/química , Células Epiteliales/efectos de la radiación , Hipertermia Inducida/instrumentación , Rayos Láser , Melanosomas/química , Epitelio Pigmentado de la Retina/citología , Temperatura , Termografía/métodos
11.
J Colloid Interface Sci ; 369(1): 287-93, 2012 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-22209581

RESUMEN

The adsorption of the non-ionic surfactants tetraoxyethylene glycol monododecyl ether (C(12)EO(4)), pentaoxyethylene glycol monododecyl ether (C(12)EO(5)), and hexaoxyethylene glycol monododecyl ether (C(12)EO(6)) to single crystal sapphire substrates has been studied using specular neutron reflection for solutions at the critical micelle concentration. The effects of temperature and pH of the solutions were studied as well as the differences between two different crystal faces, the C and the R planes. At neutral pH, significant adsorption was only observed when the temperature was raised above the cloud temperature. This adsorption was reversible and surfactant was displaced on cooling. Reducing the pH to 3 results in significantly increased adsorption of C(12)EO(5) at 25°C with a central layer consisting mainly of surfactant (about 90%) on the C-plane substrate. A slightly smaller surface excess was observed for the R-plane. This contrasts with the significantly lower density observed even at high temperatures at neutral pH on both substrates. The results suggest that for neutral solutions surfactant association above the cloud point is the primary driving force for adsorption. At low pH, specific interactions with protonated surfaces are important. The structures of the highly hydrated layers are similar to those found for the surfactants at hydrophilic silica surfaces.


Asunto(s)
Óxido de Aluminio/química , Tensoactivos/química , Adsorción , Concentración de Iones de Hidrógeno , Soluciones/química , Temperatura
12.
J Phys Chem B ; 115(15): 4427-35, 2011 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-21446656

RESUMEN

We have investigated the interfacial and bulk phase structures of surfactin at different pH and in the presence of mono/divalent cations using neutron scattering techniques. Neutron reflectivity profiles were recorded at the air/water and sapphire/water interfaces as a function of pH and ionic strength. The air/water results show that surfactin has a hydrophobic ball-like structure and that changes in pH and cations lead to changes in the area per molecule and hydrophilicity of surfactin. However the adsorption of surfactin on the hydrophilic sapphire/water interface is highly pH dependent because of electrostatic interactions with the surface. The bulk phase structures were characterized by small angle neutron scattering (SANS) and are more sensitive to pH and cation than the interfacial structure. At high pH surfactin forms micellar structures with low aggregation numbers, but at low pH values the bulk phase structure becomes rod-like at pH 6.5 and lamellar at pH 5.5. The addition of cations in the subphase tends to neutralize the two acidic groups of the peptide ring and the neutralization seems to be more complete for divalent cations than for monovalent cations.


Asunto(s)
Bacillus subtilis/química , Cationes/química , Lipopéptidos/química , Péptidos Cíclicos/química , Aire , Óxido de Aluminio/química , Concentración de Iones de Hidrógeno , Dispersión del Ángulo Pequeño , Soluciones , Propiedades de Superficie , Agua/química
13.
Pediatr Allergy Immunol ; 19(6): 497-504, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18221472

RESUMEN

The immunological composition of breast milk differs between mothers. The reasons for these differences and the consequences for the breast-fed infants are poorly understood. The aim of this study was to evaluate the effect of probiotic Lactobacillus reuteri supplementation on the immunological composition of breast milk in relation to sensitization and eczema in the babies. Total IgA, secretory IgA (SIgA), TGF-beta1, TGF-beta2, IL-10, TNF, soluble CD14 (sCD14), and Na/K ratios were analyzed in colostrum and mature milk obtained from women treated with L. reuteri (n = 54) or placebo (n = 55) from gestational week 36 until delivery. Bacteriological analyses of L. reuteri were performed in faecal samples of the mothers. The infants were followed prospectively for 2 yr regarding development of eczema and sensitization as defined by a positive skin prick test and/or circulating allergen-specific IgE antibodies at 6, 12, and 24 months of age. Supplementation of L. reuteri during pregnancy was associated with low levels of TGF-beta2 and slightly increased levels of IL-10 in colostrum. For TGF-beta2, this association was most pronounced in mothers with detectable L. reuteri in faeces. Infants receiving breast milk with low levels of TGF-beta2 were less likely to become sensitized during their first 2 yr of life. A similar trend was observed for development of IgE-associated eczema. The levels of total IgA, SIgA, TGF-beta1, TNF, sCD14, and Na/K ratios in breast milk were not affected by the intake of L. reuteri. None of these parameters correlated with sensitization or development of eczema in the infant, except for high Na/K ratios that associated with increased risk of sensitization. Supplementation with L. reuteri during late pregnancy reduces breast milk levels of TGF-beta2, and low levels of this cytokine are associated with less sensitization and possibly less IgE-associated eczema in breast-fed infants.


Asunto(s)
Calostro/química , Citocinas/análisis , Hipersensibilidad/inmunología , Limosilactobacillus reuteri/inmunología , Leche Humana/inmunología , Probióticos/administración & dosificación , Factor de Crecimiento Transformador beta2/análisis , Adulto , Lactancia Materna , Calostro/inmunología , Calostro/microbiología , Citocinas/inmunología , Método Doble Ciego , Eccema/inmunología , Eccema/prevención & control , Heces/microbiología , Femenino , Humanos , Hipersensibilidad/prevención & control , Inmunoglobulina E/sangre , Lactante , Recién Nacido , Limosilactobacillus reuteri/aislamiento & purificación , Leche Humana/química , Leche Humana/microbiología , Embarazo , Factores de Riesgo
14.
Sleep Med ; 9(5): 527-36, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17689142

RESUMEN

OBJECTIVE: To assess the effects of a 12-week Tai Chi exercise program on sleep using the sleep spectrogram, a method based on a single channel electrocardiogram (ECG)-derived estimation of cardiopulmonary coupling, previously shown to identify stable and unstable sleep states. METHODS: We retrospectively analyzed 24-h continuous ECG data obtained in a clinical trial of Tai Chi exercise in patients with heart failure. Eighteen patients with chronic stable heart failure, left ventricular ejection fraction

Asunto(s)
Electrocardiografía Ambulatoria , Insuficiencia Cardíaca/rehabilitación , Polisomnografía , Procesamiento de Señales Asistido por Computador , Privación de Sueño/rehabilitación , Trastornos del Inicio y del Mantenimiento del Sueño/rehabilitación , Taichi Chuan , Adulto , Anciano , Enfermedad Crónica , Terapia Combinada , Prueba de Esfuerzo , Femenino , Análisis de Fourier , Insuficiencia Cardíaca/psicología , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida/psicología , Privación de Sueño/psicología , Trastornos del Inicio y del Mantenimiento del Sueño/psicología
15.
Mar Pollut Bull ; 54(6): 726-32, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17328928

RESUMEN

In 2002, 13 years after the Exxon Valdez spill, mussels and clams were examined for lingering oil exposure and damage. Known oil patches were sampled at four locations, and compared to nearby reference areas (same bay), and were also compared to "hot reference" sites to verify the methods used (Cordova harbor and fresh diesel spill at Port Chalmers). Passive samplers deployed for a month at the sites, along with tissue samples, confirmed that the oiled sites were oiled (fingerprinting back to Exxon Valdez oil) and that reference sites were clean. The highest PAH loads were detected in sub-surface interstitial waters at oiled sites. Exposure at the surface was generally low level, and probably intermittent. DNA damage was assessed in blood cells using sensitive comet analyses. DNA strand breakage was detected in both mussels and clams, with the highest level of damage detected at "hot reference" sites of Cordova harbor and Port Chalmers. Bioavailability and DNA damage at the oiled sties was low, indicating there has been substantial progress in recovery from the spill 13 years before, yet low level bioavailability and damage were still detectable.


Asunto(s)
Bivalvos/efectos de los fármacos , Roturas del ADN , Exposición a Riesgos Ambientales , Mytilus/efectos de los fármacos , Petróleo/toxicidad , Hidrocarburos Policíclicos Aromáticos/toxicidad , Agua de Mar/química , Contaminantes Químicos del Agua/toxicidad , Alaska , Animales , Ensayo Cometa , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis
16.
Biomacromolecules ; 8(1): 65-9, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17206789

RESUMEN

Films formed from saliva on surfaces are important for the maintenance of oral health and integrity by protection against chemical and/or biological agents. The aim of the present study was to investigate adsorbed amounts, thickness, and structure of films formed from human whole saliva on alumina surfaces by means of in situ ellipsometry, neutron reflectivity, and atomic force microscopy. Alumina (Al2O3, synthetic sapphire) is a relevant and interesting substrate for saliva adsorption studies as it has an isoelectric point close to that of tooth enamel. The results showed that saliva adsorbs rapidly on alumina. The film could be modeled in two layers: an inner and dense thin region that forms a uniform layer and an outer, more diffuse and thicker region that protrudes toward the bulk of the solution. The film morphology described a uniformly covering dense layer and a second outer layer containing polydisperse adsorbed macromolecules or aggregates.


Asunto(s)
Óxido de Aluminio/química , Saliva/metabolismo , Adsorción , Biofisica/métodos , Materiales Dentales/química , Humanos , Microscopía de Fuerza Atómica , Microscopía Electrónica de Transmisión , Neutrones , Proteínas y Péptidos Salivales/química , Estrés Mecánico , Propiedades de Superficie , Temperatura , Factores de Tiempo
17.
Int J Gastrointest Cancer ; 32(2-3): 63-72, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12794242

RESUMEN

BACKGROUND: Pancreatic cancer is a leading cause of cancer death worldwide; current treatment options have been ineffective in prolonging survival. Agents that target specific signaling pathways (e.g., protein kinase C [PKC]) may regulate apoptotic gene expression rendering resistant cancers sensitive to the effects of other chemotherapeutic drugs. The purpose of our study was to assess the effect of PKC stimulation on apoptotic gene expression in pancreatic cancer cells. METHODS: The human pancreatic cancer cell line, PANC-1, was treated with PKC-stimulating agents, phorbol 12-myristate 13-acetate (PMA) or bryostatin-1, and analyzed for expression of apoptosis-related genes. RESULTS: Both PMA and bryostatin-1 induced expression of the pro-apoptotic gene Bad in a dose dependent fashion. The expression of Bad was blocked by the PKC inhibitors GF109203x, Gö6983, and Ro-31-8220, suggesting a role for the conventional isoforms of PKC. In addition, treatment with the MEK inhibitors PD98059 or UO126 reduced PMA-mediated induction of Bad gene expression. PMA also increased the expression of TRAIL receptors DR4 and DR5; this expression was inhibited by the PKC inhibitors GF109203x, Gö6983, and Ro-31-8220 and the MEK inhibitor UO126, suggesting a role for conventional PKC isoforms and MEK in the regulation of TRAIL receptor expression. CONCLUSIONS: PKC stimulation in PANC-1 cells increases expression of the pro-apoptotic gene Bad and the TRAIL receptors, DR4 and DR5, through both conventional PKC- and MEK-dependent pathways. Agents that stimulate PKC may sensitize pancreatic cancer cells to apoptosis and provide a potential adjuvant therapy for the treatment of chemoresistant pancreatic cancers.


Asunto(s)
Apoptosis , Proteínas Portadoras/biosíntesis , Regulación Neoplásica de la Expresión Génica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/fisiopatología , Proteína Quinasa C/farmacología , Receptores del Factor de Necrosis Tumoral/biosíntesis , Humanos , Isoenzimas , Proteína Quinasa C/química , Proteínas Proto-Oncogénicas c-bcl-2 , Células Tumorales Cultivadas , Proteína Letal Asociada a bcl
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA