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1.
Ann Oncol ; 31(12): 1734-1745, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32976938

RESUMEN

BACKGROUND: Malignant pleural mesothelioma (MPM) is an aggressive malignancy characterised by limited treatment options and a poor prognosis. At relapse after platinum-based chemotherapy, single-agent chemotherapy is commonly used and single-arm trials of immune-checkpoint inhibitors have demonstrated encouraging activity. PATIENTS AND METHODS: PROMISE-meso is an open-label 1:1 randomised phase III trial investigating the efficacy of pembrolizumab (200 mg/Q3W) versus institutional choice single-agent chemotherapy (gemcitabine or vinorelbine) in relapsed MPM patients with progression after/on previous platinum-based chemotherapy. Patients were performance status 0-1 and unselected for programmed cell death ligand 1 (PD-L1) status. At progression, patients randomly assigned to receive chemotherapy were allowed to crossover to pembrolizumab. The primary end point was progression-free survival (PFS), assessed by blinded independent central review (BICR). Secondary end points were overall survival (OS), investigator-assessed PFS, objective response rate (ORR), and safety. Efficacy by PD-L1 status was investigated in exploratory analyses. RESULTS: Between September 2017 and August 2018, 144 patients were randomly allocated (pembrolizumab: 73; chemotherapy: 71). At data cut-off [20 February 2019, median follow-up of 11.8 months (interquartile range: 9.9-14.5)], 118 BICR-PFS events were observed. No difference in BICR-PFS was detected [hazard ratio = 1.06, 95% confidence interval (CI): 0.73-1.53; P = 0.76], and median BICR-PFS (95% CI) for pembrolizumab was 2.5 (2.1-4.2), compared with 3.4 (2.2-4.3) months for chemotherapy. A difference in ORR for pembrolizumab was identified (22%, 95% CI: 13% to 33%), over chemotherapy (6%, 95% CI: 2% to 14%; P = 0.004). Forty-five patients (63%) assigned to chemotherapy received pembrolizumab at progression. With follow-up to 21 August 2019 [17.5 months: (14.8-19.7)], no difference in OS was detected between groups (HR = 1.12, 95% CI: 0.74-1.69; P = 0.59), even after adjusting for crossover. Pembrolizumab safety was consistent with previous observations. Exploratory efficacy analyses by PD-L1 status demonstrated no improvements in ORR/PFS/OS. CONCLUSION: This is the first randomised trial evaluating the efficacy of pembrolizumab in MPM patients progressing after/on previous platinum-based chemotherapy. In biologically unselected patients, although associated with an improved ORR, pembrolizumab improves neither PFS nor OS over single-agent chemotherapy.


Asunto(s)
Mesotelioma Maligno , Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Humanos , Recurrencia Local de Neoplasia
2.
Connect Tissue Res ; 61(6): 604-619, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-31443618

RESUMEN

Purpose/Aim: Substance P-NK-1R signaling has been implicated in fibrotic tendinopathies and myositis. Blocking this signaling with a neurokinin 1 receptor antagonist (NK1RA) has been proposed as a therapeutic target for their treatment.Materials and Methods: Using a rodent model of overuse injury, we pharmacologically blocked Substance P using a specific NK1RA with the hopes of reducing forelimb tendon, muscle and dermal fibrogenic changes and associated pain-related behaviors. Young adult rats learned to pull at high force levels across a 5-week period, before performing a high repetition high force (HRHF) task for 3 weeks (2 h/day, 3 days/week). HRHF rats were untreated or treated in task weeks 2 and 3 with the NK1RA, i.p. Control rats received vehicle or NK1RA treatments.Results: Grip strength declined in untreated HRHF rats, and mechanical sensitivity and temperature aversion increased compared to controls; these changes were improved by NK1RA treatment (L-732,138). NK1RA treatment also reduced HRHF-induced thickening in flexor digitorum epitendons, and HRHF-induced increases of TGFbeta1, CCN2/CTGF, and collagen type 1 in flexor digitorum muscles. In the forepaw upper dermis, task-induced increases in collagen deposition were reduced by NK1RA treatment.Conclusions: Our findings indicate that Substance P plays a role in the development of fibrogenic responses and subsequent discomfort in forelimb tissues involved in performing a high demand repetitive forceful task.


Asunto(s)
Trastornos de Traumas Acumulados/patología , Dermis/patología , Músculo Esquelético/patología , Transducción de Señal , Sustancia P/metabolismo , Tendones/patología , Animales , Restricción Calórica , Colágeno Tipo I/metabolismo , Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Modelos Animales de Enfermedad , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Fibrosis , Proteínas Musculares/metabolismo , Fosforilación , Ratas Sprague-Dawley , Receptores de Neuroquinina-1/metabolismo , Análisis y Desempeño de Tareas , Tendinopatía/patología , Factor de Crecimiento Transformador beta1/metabolismo
3.
Acta Psychiatr Scand ; 142(4): 294-306, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33314049

RESUMEN

OBJECTIVE: Sex steroid hormones potently shape brain functions, including those critical to maintain mental health such as serotonin signaling. Use of oral contraceptives (OCs) profoundly changes endogenous sex steroid hormone levels and dynamics. Recent register-based studies show that starting an OC is associated with increased risk of developing depression. Here, we investigate whether use of OCs in healthy women is associated with a marker of the serotonin system in terms of serotonin 4 receptor (5-HT4R) brain imaging. METHODS: [11C]SB207145-PET imaging data on 53 healthy women, of whom 16 used OCs, were available from the Cimbi database. We evaluated global effects of OC use on 5-HT4R binding in a latent variable model based on 5-HT4R binding across cortical and subcortical regions. RESULTS: We demonstrate that OC users have 9-12% lower global brain 5-HT4R binding potential compared to non-users. Univariate region-based analyses (pallidostriatum, caudate, hippocampus, amygdala, anterior cingulate cortex, and neocortex) supported the global effect of OC use with the largest difference present in the hippocampus (-12.8% (95% CI [-21.0; -3.9], Pcorrected = 0.03). CONCLUSION: We show that women who use OCs have markedly lower brain 5-HT4R binding relative to non-users, which constitutes a plausible molecular link between OC use and increased risk of depressive episodes. We propose that this reflects a reduced 5-HT4R gene expression, possibly related to a blunted ovarian hormone state among OC users.


Asunto(s)
Anticonceptivos Orales , Receptores de Serotonina 5-HT4 , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Femenino , Humanos , Neuroimagen , Tomografía de Emisión de Positrones , Receptores de Serotonina 5-HT4/metabolismo
4.
Clin Radiol ; 75(6): 423-432, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32081346

RESUMEN

Malignant pleural mesothelioma (MPM) is a primary malignancy of the pleura and is associated with a poor outcome. The symptoms and signs of malignant mesothelioma present late in the natural history of the disease and are non-specific, making the diagnosis challenging and imaging key. In 2018, the British Thoracic Society (BTS) updated the guideline on diagnosis, staging, and follow-up of patients with MPM. These recommendations are discussed in this review of the current literature on imaging of MPM. It is estimated MPM will continue to cause serious morbidity and mortality in the UK late into the 21st century, and internationally, people continue to be exposed to asbestos. We aim to update the reader on current and future imaging strategies, which could aid early diagnosis of pleural malignancy and provide an update on staging and assessment of tumour response.


Asunto(s)
Diagnóstico por Imagen/normas , Mesotelioma Maligno/diagnóstico por imagen , Neoplasias Pleurales/diagnóstico por imagen , Guías de Práctica Clínica como Asunto , Detección Precoz del Cáncer , Humanos , Mesotelioma Maligno/patología , Estadificación de Neoplasias , Neoplasias Pleurales/patología , Sociedades Médicas
5.
Regul Toxicol Pharmacol ; 106: 55-67, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31028797

RESUMEN

We describe a novel experimental method that mimics exposure to dried agrochemical residues on contact surfaces during re-entry into crops. It includes the creation of dry dislodgeable residues and subsequent transfer to human skin for in vitro measurement of dermal absorption within a standard Organisation for Economic Co-operation and Development test guideline (OECD TG) 428 study. A pre-determined volume of spray containing 14C-labelled active substance is transferred onto a polytetrafluorethylene-coated septum and air-dried. The septum is then gently placed onto the pre-wetted skin mounted in a flow-through Franz diffusion chamber. The septum is gently rotated thrice to transfer the dose. Preliminary tests determined transfer efficiency to ensure the appropriate test concentration on the skin. Then, a standard dermal absorption study is performed according to OECD TG 428. Results from 10 compounds indicate that the methodology can be robustly incorporated into a standard TG study. These data show that the dermal absorption from a dry dislodgeable residue is lower than that from the equivalent dose of the aqueous spray, regardless of formulation type or active substance. Studies following the scenario described above can be a suitable tool to better estimate dermal absorption from dry residues in re-entry worker and resident exposure assessment for agrochemicals.


Asunto(s)
Agroquímicos/metabolismo , Organización para la Cooperación y el Desarrollo Económico , Residuos de Plaguicidas/metabolismo , Absorción Cutánea , Piel/metabolismo , Agroquímicos/química , Agroquímicos/farmacocinética , Difusión , Humanos , Residuos de Plaguicidas/química , Residuos de Plaguicidas/farmacocinética , Piel/química
6.
Gene Ther ; 24(12): 757-767, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29106403

RESUMEN

DNA vaccines delivered using electroporation (EP) have had clinical success, but these EP methods generally utilize invasive needle electrodes. Here, we demonstrate the delivery and immunogenicity of a DNA vaccine into subcutaneous adipose tissue cells using noninvasive EP. Using finite element analysis, we predicted that plate electrodes, when oriented properly, could effectively concentrate the electric field within adipose tissue. In practice, these electrodes generated widespread gene expression persisting for at least 60 days in vivo within interscapular subcutaneous fat pads of guinea pigs. We then applied this adipose-EP protocol to deliver a DNA vaccine coding for an influenza antigen into guinea pigs. The resulting host immune responses elicited were of a similar magnitude to those achieved by skin delivery with EP. The onset of the humoral immune response was more rapid when the DNA dose was spread over multiple injection sites, and increasing the voltage of the EP device increased the magnitude of the immune response. This study supports further development of EP protocols delivering gene-based therapies to subcutaneous fat.


Asunto(s)
Tejido Adiposo/metabolismo , Electroporación/métodos , Terapia Genética , Vacunas de ADN/administración & dosificación , Animales , Anticuerpos Antivirales/biosíntesis , Electrodos , Ensayo de Inmunoadsorción Enzimática , Análisis de Elementos Finitos , Expresión Génica , Cobayas , Humanos , Inmunidad Celular , Gripe Humana/inmunología , Orthomyxoviridae/inmunología , Transfección , Vacunas de ADN/inmunología
7.
J Neurosci ; 35(14): 5884-9, 2015 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-25855196

RESUMEN

The cerebral serotonin (5-HT) system shows distinct differences in obesity compared with the lean state. Here, it was investigated whether serotonergic neurotransmission in obesity is a stable trait or changes in association with weight loss induced by Roux-in-Y gastric bypass (RYGB) surgery. In vivo cerebral 5-HT2A receptor and 5-HT transporter binding was determined by positron emission tomography in 21 obese [four men; body mass index (BMI), 40.1 ± 4.1 kg/m(2)] and 10 lean (three men; BMI, 24.6 ± 1.5 kg/m(2)) individuals. Fourteen obese individuals were re-examined after RYGB surgery. First, it was confirmed that obese individuals have higher cerebral 5-HT2A receptor binding than lean individuals. Importantly, we found that higher presurgical 5-HT2A receptor binding predicted greater weight loss after RYGB and that the change in 5-HT2A receptor and 5-HT transporter binding correlated with weight loss after RYGB. The changes in the 5-HT neurotransmission before and after RYGB are in accordance with a model wherein the cerebral extracellular 5-HT level modulates the regulation of body weight. Our findings support that the cerebral 5-HT system contributes both to establish the obese condition and to regulate the body weight in response to RYGB.


Asunto(s)
Encéfalo/patología , Derivación Gástrica/métodos , Obesidad/cirugía , Receptor de Serotonina 5-HT2A/metabolismo , Pérdida de Peso/fisiología , Adulto , Índice de Masa Corporal , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Estudios de Casos y Controles , Dinamarca , Femenino , Péptido 1 Similar al Glucagón/sangre , Humanos , Ketanserina/análogos & derivados , Ketanserina/farmacocinética , Masculino , Persona de Mediana Edad , Obesidad/sangre , Obesidad/diagnóstico por imagen , Unión Proteica/efectos de los fármacos , Cintigrafía , Antagonistas de la Serotonina/farmacocinética , Factores de Tiempo , Resultado del Tratamiento
8.
Biochim Biophys Acta ; 1840(4): 1413-32, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24161926

RESUMEN

BACKGROUND: Most neurodegenerative diseases are associated with mitochondrial dysfunction. In humans, mutations in mitochondrial genes result in a range of phenotypic outcomes which do not correlate well with the underlying genetic cause. Other neurodegenerative diseases are caused by mutations that affect the function and trafficking of lysosomes, endosomes and autophagosomes. Many of the complexities of these human diseases can be avoided by studying them in the simple eukaryotic model Dictyostelium discoideum. SCOPE OF REVIEW: This review describes research using Dictyostelium to study cytopathological pathways underlying a variety of neurodegenerative diseases including mitochondrial, lysosomal and vesicle trafficking disorders. MAJOR CONCLUSIONS: Generalised mitochondrial respiratory deficiencies in Dictyostelium produce a consistent pattern of defective phenotypes that are caused by chronic activation of a cellular energy sensor AMPK (AMP-activated protein kinase) and not ATP deficiency per se. Surprisingly, when individual subunits of Complex I are knocked out, both AMPK-dependent and AMPK-independent, subunit-specific phenotypes are observed. Many nonmitochondrial proteins associated with neurological disorders have homologues in Dictyostelium and are associated with the function and trafficking of lysosomes and endosomes. Conversely, some genes associated with neurodegenerative disorders do not have homologues in Dictyostelium and this provides a unique avenue for studying these mutated proteins in the absence of endogeneous protein. GENERAL SIGNIFICANCE: Using the Dictyostelium model we have gained insights into the sublethal cytopathological pathways whose dysregulation contributes to phenotypic outcomes in neurodegenerative disease. This work is beginning to distinguish correlation, cause and effect in the complex network of cross talk between the various organelles involved. This article is part of a Special Issue entitled Frontiers of Mitochondrial Research.


Asunto(s)
Encefalopatías Metabólicas , Dictyostelium , Enfermedades Mitocondriales , Modelos Neurológicos , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Encefalopatías Metabólicas/metabolismo , Encefalopatías Metabólicas/patología , Dictyostelium/genética , Dictyostelium/metabolismo , Dictyostelium/ultraestructura , Humanos , Mitocondrias/genética , Mitocondrias/metabolismo , Enfermedades Mitocondriales/metabolismo , Enfermedades Mitocondriales/patología , Organismos Modificados Genéticamente , Fosforilación Oxidativa
9.
Mol Psychiatry ; 19(4): 427-32, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24189342

RESUMEN

Identification of a biomarker that can inform on extracellular serotonin (5-HT) levels in the brains of living humans would enable greater understanding of the way brain circuits are modulated by serotonergic neurotransmission. Substantial evidence from studies in animals and humans indicates an inverse relationship between central 5-HT tonus and 5-HT type 4 receptor (5-HT4R) density, suggesting that 5-HT4R receptor density may be a biomarker marker for 5-HT tonus. Here, we investigated whether a 3-week administration of a selective serotonin reuptake inhibitor, expected to increase brain 5-HT levels, is associated with a decline in brain 5-HT4R binding. A total of 35 healthy men were studied in a placebo-controlled, randomized, double-blind study. Participants were assigned to receive 3 weeks of oral dosing with placebo or fluoxetine, 40 mg per day. Brain 5-HT4R binding was quantified at baseline and at follow-up with [(11)C]SB207145 positron emission tomography (PET). Three weeks of intervention with fluoxetine was associated with a 5.2% reduction in brain 5-HT4R binding (P=0.017), whereas placebo intervention did not change 5-HT4R binding (P=0.52). Our findings are consistent with a model, wherein the 5-HT4R density adjusts to changes in the extracellular 5-HT tonus. Our data demonstrate for the first time in humans that the imaging of central 5-HT4R binding may be used as an in vivo biomarker of the central 5-HT tonus.


Asunto(s)
Encéfalo/efectos de los fármacos , Encéfalo/diagnóstico por imagen , Piperidinas/farmacocinética , Tomografía de Emisión de Positrones , Receptores de Serotonina 5-HT4/metabolismo , Adulto , Radioisótopos de Carbono/farmacocinética , Método Doble Ciego , Fluoxetina/farmacología , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Unión Proteica/efectos de los fármacos , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Adulto Joven
10.
Regul Toxicol Pharmacol ; 72(1): 58-70, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25765508

RESUMEN

Dermal absorption is a key parameter in non-dietary human safety assessments for agrochemicals. Conservative default values and other criteria in the EFSA guidance have substantially increased generation of product-specific in vitro data and in some cases, in vivo data. Therefore, data from 190 GLP- and OECD guideline-compliant human in vitro dermal absorption studies were published, suggesting EFSA defaults and criteria should be revised (Aggarwal et al., 2014). This follow-up article presents data from an additional 171 studies and also the combined dataset. Collectively, the data provide consistent and compelling evidence for revision of EFSA's guidance. This assessment covers 152 agrochemicals, 19 formulation types and representative ranges of spray concentrations. The analysis used EFSA's worst-case dermal absorption definition (i.e., an entire skin residue, except for surface layers of stratum corneum, is absorbed). It confirmed previously proposed default values of 6% for liquid and 2% for solid concentrates, irrespective of active substance loading, and 30% for all spray dilutions, irrespective of formulation type. For concentrates, absorption from solvent-based formulations provided reliable read-across for other formulation types, as did water-based products for solid concentrates. The combined dataset confirmed that absorption does not increase linearly beyond a 5-fold increase in dilution. Finally, despite using EFSA's worst-case definition for absorption, a rationale for routinely excluding the entire stratum corneum residue, and ideally the entire epidermal residue in in vitro studies, is presented.


Asunto(s)
Plaguicidas/química , Plaguicidas/metabolismo , Absorción Cutánea/fisiología , Piel/metabolismo , Humanos , Medición de Riesgo , Solventes/química , Solventes/metabolismo , Agua/química , Agua/metabolismo
11.
Br J Cancer ; 111(1): 101-11, 2014 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-24892445

RESUMEN

BACKGROUND: Akt and its downstream signalling pathways contribute to the aetiology and progression of colorectal carcinoma (CRC). Targeting the Akt pathway is an attractive strategy but few chemotherapeutic drugs have been used to treat CRC with only limited success. BI-69A11, a small molecule inhibitor of Akt, efficiently inhibits growth in melanoma cells. Melanoma differentiation associated gene-7 (mda-7)/interleukin-24 promotes cancer-selective apoptosis when delivered by a tropism-modified replication incompetent adenovirus (Ad.5/3-mda-7). However, Ad.5/3-mda-7 displays diminished antitumour efficacy in several CRC cell lines, which correlates with the expression of K-RAS. METHODS: The individual and combinatorial effect of BI-69A11 and Ad.5/3-mda-7 in vitro was studied by cell viability, cell cycle, apoptosis and invasion assays in HT29 and HCT116 cells containing wild type or mutant K-ras, respectively. In vivo HT29 tumour xenografts were used to test the efficacy of the combination treatment. RESULTS: BI-69A11 inhibited growth and induced apoptosis in CRC. However, combinatorial treatment was more effective compared with single treatment. This combination showed profound antitumour and anti angiogenic effects in vitro and in vivo by downregulating Akt activity. CONCLUSIONS: BI-69A11 enhances the antitumour efficacy of Ad.5/3-mda-7 on CRC overexpressing K-RAS by inducing apoptosis and regulating Akt activity thereby warranting further evaluation in treating CRC.


Asunto(s)
Bencimidazoles/farmacología , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/terapia , Interleucinas/genética , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Quinolonas/farmacología , Adenoviridae/genética , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Procesos de Crecimiento Celular/efectos de los fármacos , Procesos de Crecimiento Celular/genética , Línea Celular Tumoral , Embrión de Pollo , Membrana Corioalantoides/irrigación sanguínea , Membrana Corioalantoides/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Femenino , Células HCT116 , Células HT29 , Humanos , Interleucinas/biosíntesis , Ratones , Ratones Desnudos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Distribución Aleatoria , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Nature ; 451(7177): 437-40, 2008 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-18216848

RESUMEN

The atmospheres of the gas giant planets (Jupiter and Saturn) contain jets that dominate the circulation at visible levels. The power source for these jets (solar radiation, internal heat, or both) and their vertical structure below the upper cloud are major open questions in the atmospheric circulation and meteorology of giant planets. Several observations and in situ measurements found intense winds at a depth of 24 bar, and have been interpreted as supporting an internal heat source. This issue remains controversial, in part because of effects from the local meteorology. Here we report observations and modelling of two plumes in Jupiter's atmosphere that erupted at the same latitude as the strongest jet (23 degrees N). The plumes reached a height of 30 km above the surrounding clouds, moved faster than any other feature (169 m s(-1)), and left in their wake a turbulent planetary-scale disturbance containing red aerosols. On the basis of dynamical modelling, we conclude that the data are consistent only with a wind that extends well below the level where solar radiation is deposited.

13.
Anim Genet ; 45(1): 142-3, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24033517

RESUMEN

Red deer behaviour prevents the accurate physical matching of dams to fawns and, therefore, breeders have to rely on DNA-based parentage testing. A panel consisting of 100 single nucleotide polymorphism markers, with an average minor allele frequency of 0.25, was able to resolve 92% of fawns to both parents. In comparison, an existing 12-marker microsatellite panel was able to resolve 68% of fawns to both parents. When excluding dam DNA information, the single nucleotide polymorphism panel matched 81% of the fawns to their sires and the microsatellite panel 71%.


Asunto(s)
Ciervos/genética , Polimorfismo de Nucleótido Simple , Animales , Cruzamiento , Femenino , Frecuencia de los Genes , Marcadores Genéticos , Masculino , Repeticiones de Microsatélite , Linaje
14.
Regul Toxicol Pharmacol ; 68(3): 412-23, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24491967

RESUMEN

Dermal absorption is an integral part of non-dietary human safety risk assessments for agrochemicals. Typically, dermal absorption data for agrochemical active substances are generated from the undiluted formulation concentrate and its spray dilutions. European Food Safety Authority (EFSA) guidance, which combines highly conservative default values, very limited opportunities for read-across from existing data and other overly conservative conclusions, was the driver for this assessment. To investigate the reliability of the EFSA guidance, a homogeneous data-set of 190 GLP and OECD guideline compliant in vitro human skin studies, chosen to match the test method preferred by EU data requirements, was evaluated. These studies represented a wide range of active substances, formulation types, and concentrations. In alignment with EFSA guidance on human exposure assessment, a conservative estimate of absorption (95th percentile) was chosen to define defaults, which were also based on the EFSA worst-case assumption that all material in skin, excluding the first two tape strips, is absorbed. The analysis supports dermal absorption defaults of 6% for liquid concentrates, 2% for solid concentrates, and 30% for all spray dilutions, irrespective of the active substance concentration. Relatively high dermal absorption values for organic solvent-based formulations, compared to water-based or solid concentrates, support their use as worst-case surrogate data for read-across to other formulation types. The current review also shows that dermal absorption of sprays does not increase linearly with increasing dilution, and provides a novel, science-based option for extrapolation from existing data.


Asunto(s)
Plaguicidas/farmacocinética , Absorción Cutánea , Animales , Humanos , Técnicas In Vitro , Medición de Riesgo , Piel/metabolismo
15.
Rev Sci Tech ; 33(1): 281-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25000801

RESUMEN

The management of vertebrate pests depends on the use of traps, pesticides, repellents and other methods, each of which can cause varying levels of pain and other negative experiences to animals. Vertebrate pest control is essential for managing the impacts of unwanted or over-abundant animals on human and animal health, ecological balance and economic interests. As the need for this management is unlikely to diminish over time, a framework has been developed for assessing the humaneness of each technique by considering their negative impacts on animal welfare so that these can be included in decision-making about the selection of techniques for a specific control operation. This information can also support evidence-based regulations directed at managing such animal welfare impacts. In this paper, the authors discuss this assessment framework, briefly review two assessments conducted using the framework and discuss ways in which Competent Authorities and others can use it and other means to improve animal welfare in vertebrate pest management.


Asunto(s)
Bienestar del Animal , Control de Plagas , Vertebrados , Animales , Modelos Biológicos , Factores de Tiempo
16.
Clin Epigenetics ; 16(1): 71, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802956

RESUMEN

BACKGROUND: Methylation of serotonin-related genes has been proposed as a plausible gene-by-environment link which may mediate environmental stress, depressive and anxiety symptoms. DNA methylation is often measured in blood cells, but little is known about the association between this peripheral epigenetic modification and brain serotonergic architecture. Here, we evaluated the association between whole-blood-derived methylation of four CpG sites in the serotonin transporter (SLC6A4) and six CpG sites of the tryptophan hydroxylase 2 (TPH2) gene and in-vivo brain levels of serotonin transporter (5-HTT) and serotonin 4 receptor (5-HT4) in a cohort of healthy individuals (N = 254) and, for 5-HT4, in a cohort of unmedicated patients with depression (N = 90). To do so, we quantified SLC6A4/TPH2 methylation using bisulfite pyrosequencing and estimated brain 5-HT4 and 5-HTT levels using positron emission tomography. In addition, we explored the association between SLC6A4 and TPH2 methylation and measures of early life and recent stress, depressive and anxiety symptoms on 297 healthy individuals. RESULTS: We found no statistically significant association between peripheral DNA methylation and brain markers of serotonergic neurotransmission in patients with depression or in healthy individuals. In addition, although SLC6A4 CpG2 (chr17:30,236,083) methylation was marginally associated with the parental bonding inventory overprotection score in the healthy cohort, statistical significance did not remain after accounting for blood cell heterogeneity. CONCLUSIONS: We suggest that findings on peripheral DNA methylation in the context of brain serotonin-related features should be interpreted with caution. More studies are needed to rule out a role of SLC6A4 and TPH2 methylation as biomarkers for environmental stress, depressive or anxiety symptoms.


Asunto(s)
Encéfalo , Metilación de ADN , Depresión , Epigénesis Genética , Proteínas de Transporte de Serotonina en la Membrana Plasmática , Serotonina , Transmisión Sináptica , Triptófano Hidroxilasa , Humanos , Metilación de ADN/genética , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Masculino , Femenino , Adulto , Triptófano Hidroxilasa/genética , Serotonina/metabolismo , Serotonina/sangre , Encéfalo/metabolismo , Depresión/genética , Depresión/metabolismo , Epigénesis Genética/genética , Transmisión Sináptica/genética , Islas de CpG/genética , Persona de Mediana Edad , Adulto Joven , Receptores de Serotonina 5-HT4/genética , Receptores de Serotonina 5-HT4/metabolismo , Tomografía de Emisión de Positrones , Estudios de Cohortes
17.
Phys Rev Lett ; 111(16): 164801, 2013 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-24182271

RESUMEN

High-power, relativistic electron beams from energy-recovering linacs have great potential to realize new experimental paradigms for pioneering innovation in fundamental and applied research. A major design consideration for this new generation of experimental capabilities is the understanding of the halo associated with these bright, intense beams. In this Letter, we report on measurements performed using the 100 MeV, 430 kW cw electron beam from the energy-recovering linac at the Jefferson Laboratory's Free Electron Laser facility as it traversed a set of small apertures in a 127 mm long aluminum block. Thermal measurements of the block together with neutron measurements near the beam-target interaction point yielded a consistent understanding of the beam losses. These were determined to be 3 ppm through a 2 mm diameter aperture and were maintained during a 7 h continuous run.

18.
J Neurooncol ; 113(3): 479-83, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23673514

RESUMEN

Optic pathway glioma (OPG) has an unpredictable course, with poor correlation between conventional imaging features and tumor progression. We investigated whether diffusion-weighted MRI (DWI) predicts the clinical behavior of these tumors. Twelve children with OPG (median age 2.7 years; range 0.4-6.2 years) were followed for a median 4.4 years with DWI. Progression-free survival (time to requiring therapy) was compared between tumors stratified by apparent diffusion coefficient (ADC) from initial pre-treatment scans. Tumors with baseline ADC greater than 1,400 × 10(-6) mm(2)/s required treatment earlier than those with lower ADC (log-rank p = 0.002). In some cases, ADC increased leading up to treatment, and declined following treatment with surgery, chemotherapy, or radiation. Baseline ADC was higher in tumors that eventually required treatment (1,562 ± 192 × 10(-6) mm(2)/s), compared with those conservatively managed (1,123 ± 114 × 10(-6) mm(2)/s) (Kruskal-Wallis test p = 0.013). Higher ADC predicted earlier tumor progression in this cohort and in some cases declined after therapy. Evaluation of OPG with DWI may therefore be useful for predicting tumor behavior and assessing treatment response.


Asunto(s)
Neoplasias Encefálicas/patología , Imagen de Difusión por Resonancia Magnética , Glioma del Nervio Óptico/patología , Neoplasias Encefálicas/mortalidad , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Procesamiento de Imagen Asistido por Computador , Lactante , Masculino , Glioma del Nervio Óptico/mortalidad , Pronóstico , Tasa de Supervivencia
19.
Environ Sci Technol ; 47(2): 1073-81, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23198708

RESUMEN

Understanding the relationships between accumulated metal speciation in cells and tissues of ecologically significant taxa such as earthworms will improve risk assessments. Synchrotron-based µ-focus X-ray spectroscopy was used to detect, localize, and determine ligand-speciation of Zn and Pb in thin sections of two epigeic earthworm species collected from a Pb/Zn-mine soil. The findings indicated that Zn and Pb partition predominantly as typical hard acids (i.e., strong affinities for O-donors) within liverlike chloragocytes. Moreover, Zn speciation was very similar in the chloragog and intestinal epithelia but differed subtly in the kidneylike nephridial tubules; neither Zn nor Pb was detectable in the ventral nerve cord. High resolution X-ray mapping of high pressure-frozen, ultrathin, freeze-substituted sections in a transmission electron microscope (TEM), combined with conventional TEM structural analysis, identified a new cell type packed with highly organized rough endoplasmic reticulum and containing deposits of Cd (codistributed with S); there was no evidence that these cells are major depositories of Zn or Pb. These data may be used in a systems biology approach to assist in the interpretation of metal-evoked perturbations in whole-worm transcriptome and metabolome profiles.


Asunto(s)
Cadmio/análisis , Plomo/análisis , Oligoquetos/metabolismo , Oligoquetos/ultraestructura , Contaminantes del Suelo/análisis , Zinc/análisis , Animales , Cadmio/metabolismo , Microanálisis por Sonda Electrónica , Monitoreo del Ambiente , Plomo/metabolismo , Suelo/análisis , Contaminantes del Suelo/metabolismo , Sincrotrones , Espectroscopía de Absorción de Rayos X , Rayos X , Zinc/metabolismo
20.
Bull Environ Contam Toxicol ; 88(2): 226-8, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22105934

RESUMEN

Approximately 700 kg of cereal bait containing 20 ppm of the anticoagulant rodenticide brodifacoum was spilled into a southern New Zealand lake in 2010 from a helicopter being used to transport containers of brodifacoum bait for an aerial baiting operation. In the month after the spill no residual brodifacoum was detected in samples of lake water, sediment, benthic invertebrates, eels, and two birds.


Asunto(s)
4-Hidroxicumarinas/análisis , Liberación de Peligros Químicos , Lagos/química , Rodenticidas/análisis , Contaminantes Químicos del Agua/análisis , 4-Hidroxicumarinas/metabolismo , Aeronaves , Animales , Aves/metabolismo , Anguilas/metabolismo , Monitoreo del Ambiente , Sedimentos Geológicos/química , Invertebrados/metabolismo , Nueva Zelanda , Rodenticidas/metabolismo , Contaminantes Químicos del Agua/metabolismo
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