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2.
Eur J Nucl Med Mol Imaging ; 49(9): 3162-3172, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35165788

RESUMEN

PURPOSE: Chronic traumatic encephalopathy refers to a neurodegenerative disease resulting from repetitive head injury of participants in contact sports. Similar to other neurodegenerative diseases, neuroinflammation is thought to play a role in the onset and progression of the disease. Limited knowledge is available regarding the neuroinflammatory consequences of repetitive head injury in currently active contact sports athletes. PET imaging of the 18-kDa translocator protein (TSPO) allows quantification of microglial activation in vivo, a marker of neuroinflammation. METHODS: Eleven rank A kickboxers and 11 age-matched controls underwent TSPO PET using [11C]-PK11195, anatomical MRI, diffusion tensor imaging, and neuropsychological testing. Relevant imaging parameters were derived and correlated with the outcomes of the neuropsychological testing. RESULTS: On a group level, no statistically significant differences were detected in non-displaceable binding potential (BPND) using PET. Individually, 3 kickboxers showed increased BPNDs in widespread regions of the brain without a correlation with other modalities. Increased FA was observed in the superior corona radiata bilaterally. DTI parameters in other regions did not differ between groups. CONCLUSION: Despite negative results on a group level, individual results suggest that neuroinflammation may be present as a consequence of repetitive head injury in active kickboxers. Future studies using a longitudinal design may determine whether the observed TSPO upregulation is related to the future development of neuropsychiatric symptoms.


Asunto(s)
Traumatismos en Atletas , Traumatismos Craneocerebrales , Enfermedades Neurodegenerativas , Enfermedades Neuroinflamatorias , Traumatismos en Atletas/diagnóstico por imagen , Encéfalo/metabolismo , Traumatismos Craneocerebrales/diagnóstico por imagen , Traumatismos Craneocerebrales/metabolismo , Imagen de Difusión Tensora , Humanos , Artes Marciales/lesiones , Enfermedades Neurodegenerativas/diagnóstico por imagen , Enfermedades Neuroinflamatorias/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Receptores de GABA/metabolismo
3.
Psychiatry Res Neuroimaging ; 311: 111284, 2021 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-33774451

RESUMEN

Pornographic addiction refers to an addiction model associated with compulsive and repeated use of pornographic material. Whether the use of pornography may indeed become addictive remains a matter of debate. The current study investigated whether compulsive pornography use (CPU) is accompanied by reduced D2/3 receptor availability in the striatum and frontal hypofunctionality. Male subjects between 18 and 50 years of age with and without CPU were recruited using online and newspaper advertisements. Questionnaires were used to the assess the severity of compulsive pornography use (CIUS) and symptoms of depression, impulsivity and sensation seeking. Dopaminergic imaging was performed using [11C]-raclopride PET. Striatal binding potentials (BPND) and regional frontal cerebral influx values (R1) of [11C]-raclopride were calculated. Arterial Spin Labeling (ASL) MRI was performed to assess regional cerebral blood flow. No group differences between striatal BPND's of [11C]-raclopride in subjects with (n = 15) and without (n = 10) CPU were detected. In CPU subjects, no correlation was found between the CIUS score and striatal BPND's. Cerebral R1 values in frontal brain regions and cerebral blood flow measurements did not differ between groups. The current study fails to provide imaging support for sharing similar neurobiological alterations as previously has been reported in other addictive modalities.


Asunto(s)
Literatura Erótica , Tomografía de Emisión de Positrones , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/metabolismo , Humanos , Masculino , Racloprida , Receptores de Dopamina D2/metabolismo
4.
Neuroimage Clin ; 25: 102161, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31981888

RESUMEN

AIM: L -3,4-dihydroxy-6-18F-fluorophenylalanine (18F-DOPA PET may be used to distinguish subjects with Parkinsonism from those with symptoms not originating from impaired dopaminergic transmission. However, it is not routinely utilized to discriminate Idiopathic Parkinson's disease (IPD) from Atypical Parkinsonian Disorders (APD). We investigated the potential of FDOPA PET to discriminate between IPD and APD, with a focus on the anterior-to-posterior decline in het striatum, considered to be more specific for IPD. MATERIALS AND METHODS: 18F-DOPA PET data from a total of 58 subjects were retrospectively analyzed. 28 subjects had idiopathic Parkinson's disease (14 male, 14 female; age at scan 61 +- 11,5), 13 atypical Parkinsonian disease (7 male, 6 females; age at scan: 69,6 +- 6,4) and 17 were controls (6 male, 11 female; age at scan 65,3 +-8,6). Regional striatal-to-occipital ratio's (RSOR's) were calculated, as well as multiple in-line VOI's from the caudate nucleus to the posterior part of the putamen. The linearity of anteroposterior decline was determined by a linear regression fit and associated R squared values. ROC curves were calculated to assess the diagnostic performance of these measurements. Data contralateral to the clinically most affected side were used for analysis. RESULTS: ROC curve analysis for differentiation between controls and Parkinsonism patients showed the highest AUC for the caudate nucleus-to-posterior putamen ratio (AUC = 0.930; p < 0.00) and for the R squared value for the linear regression fit (AUC = 0.948; p = 0.006). For discrimating IPD from APD, the highest AUC was found for the caudate nucleus-to-anterior putamen ratio (0.824; p < 0.001) CONCLUSIONS: Subregional analysis of the striatum in F-DOPA PET scans may provide additional diagnostic information in patients screened for a  presynaptic dopaminergic deficit. A more linear decrease from the head of the caudate nucleus to the posterior putamen was  present in patients with IPD, although this feature did not have additional diagnostic value over the RSOR analysis.


Asunto(s)
Cuerpo Estriado/diagnóstico por imagen , Dihidroxifenilalanina/análogos & derivados , Neuroimagen/métodos , Trastornos Parkinsonianos/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Anciano , Núcleo Caudado/diagnóstico por imagen , Diagnóstico Diferencial , Dihidroxifenilalanina/farmacocinética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/diagnóstico por imagen , Putamen/diagnóstico por imagen , Estudios Retrospectivos
5.
Oncogene ; 38(22): 4425, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31068666

RESUMEN

The original version of this article contained an error in Fig. 5a where the colours of the labels representing the Hinge and LBD of the AR were incorrect and did not match the corresponding exons. The corrected version of this Figure now appears in the article. The conclusions of this paper were not affected. The authors apologise for this error and any confusion caused.

6.
Oncogene ; 38(22): 4412-4424, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30742096

RESUMEN

Stem cell characteristics have been associated with treatment resistance and poor prognosis across many cancer types. The ability to induce and regulate the pathways that sustain these characteristic hallmarks of lethal cancers in a novel in vitro model would greatly enhance our understanding of cancer progression and treatment resistance. In this work, we present such a model, based simply on applying standard pluripotency/embryonic stem cell media alone. Core pluripotency stem cell master regulators (OCT4, SOX2 and NANOG) along with epithelial-mesenchymal transition (EMT) markers (Snail, Slug, vimentin and N-cadherin) were induced in human prostate, breast, lung, bladder, colorectal, and renal cancer cells. RNA sequencing revealed pathways activated by pluripotency inducing culture that were shared across all cancers examined. These pathways highlight a potential core mechanism of treatment resistance. With a focus on prostate cancer, the culture-based induction of core pluripotent stem cell regulators was shown to promote survival in castrate conditions-mimicking first line treatment resistance with hormonal therapies. This acquired phenotype was shown to be mediated through the upregulation of iodothyronine deiodinase DIO2, a critical modulator of the thyroid hormone signalling pathway. Subsequent inhibition of DIO2 was shown to supress expression of prostate specific antigen, the cardinal clinical biomarker of prostate cancer progression and highlighted a novel target for clinical translation in this otherwise fatal disease. This study identifies a new and widely accessible simple preclinical model to recreate and explore underpinning pathways of lethal disease and treatment resistance.

7.
J Patient Rep Outcomes ; 2(1): 11, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29757295

RESUMEN

BACKGROUND: Comprehensive assessment of systemic lupus erythematosus (SLE) and its treatment requires patient-reported outcome (PRO) measures to capture impacts and fluctuating symptoms. The objective of this study was to develop PROs, in accordance with the Food and Drug Administration (FDA) PRO Guidance, to assess fluctuations in SLE symptoms and its impact. METHODS: Following independent review board approval, six US rheumatology practices recruited patients with SLE to participate in concept elicitation (CE) interviews, in order to identify important SLE symptoms and their impacts. The SLE Symptom Severity Diary (SSD) and SLE Impact Questionnaire (SIQ) were drafted based on CE interview results and clinician input. The PROs were revised based on patient feedback from cognitive debriefing (CD) interviews, clinician feedback, and a translatability assessment. RESULTS: Forty-one patients completed CE interviews. Commonly-reported symptoms included fatigue (98%), joint pain (93%), and rash (88%). The most frequently reported impact was difficulty with chores/housework (61%). Eighteen patients completed CD interviews. The PROs were considered comprehensive, clear, and relevant.The SSD contains 17 items assessing energy/vitality, joint and muscle pain/stiffness/swelling, flu-like symptoms, cognition, numbness/tingling, skin symptoms and hair loss using an 11-point numeric response scale and a 24-h recall period (with the exception of hair loss). It also evaluates steroid status and dose. The SIQ contains 50 items, uses a 5-point Likert scale and a 7-day recall period, to assess disease impacts including patients' ability to make plans, work, and physical/social/emotional functioning. CONCLUSION: The SSD and SIQ are comprehensive SLE-specific PROs developed in accordance with the FDA PRO Guidance. Following assessment of their measurement properties, they may be useful in clinical studies and clinical practice to measure fluctuations in, and the impact of, symptoms in patients with SLE.

9.
PLoS One ; 10(3): e0116599, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25756792

RESUMEN

Spinocerebellar ataxia type 13 (SCA13) is an autosomal dominantly inherited neurodegenerative disorder of the cerebellum caused by mutations in the voltage gated potassium channel KCNC3. To identify novel pathogenic SCA13 mutations in KCNC3 and to gain insights into the disease prevalence in the Netherlands, we sequenced the entire coding region of KCNC3 in 848 Dutch cerebellar ataxia patients with familial or sporadic origin. We evaluated the pathogenicity of the identified variants by co-segregation analysis and in silico prediction followed by biochemical and electrophysiological studies. We identified 19 variants in KCNC3 including 2 non-coding, 11 missense and 6 synonymous variants. Two missense variants did not co-segregate with the disease and were excluded as potentially disease-causing mutations. We also identified the previously reported p.R420H and p.R423H mutations in our cohort. Of the remaining 7 missense variants, functional analysis revealed that 2 missense variants shifted Kv3.3 channel activation to more negative voltages. These variations were associated with early disease onset and mild intellectual disability. Additionally, one other missense variant shifted channel activation to more positive voltages and was associated with spastic ataxic gait. Whereas, the remaining missense variants did not change any of the channel characteristics. Of these three functional variants, only one variant was in silico predicted to be damaging and segregated with disease. The other two variants were in silico predicted to be benign and co-segregation analysis was not optimal or could only be partially confirmed. Therefore, we conclude that we have identified at least one novel pathogenic mutation in KCNC3 that cause SCA13 and two additionally potential SCA13 mutations. This leads to an estimate of SCA13 prevalence in the Netherlands to be between 0.6% and 1.3%.


Asunto(s)
Canales de Potasio Shaw/genética , Canales de Potasio Shaw/metabolismo , Ataxias Espinocerebelosas/genética , Población Blanca/genética , Adulto , Anciano , Simulación por Computador , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Células HeLa , Humanos , Persona de Mediana Edad , Mutación , Países Bajos , Análisis de Secuencia de ADN , Ataxias Espinocerebelosas/metabolismo , Adulto Joven
10.
J Alzheimers Dis ; 43(3): 871-91, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25125467

RESUMEN

BACKGROUND: Down syndrome (DS) is the most prevalent genetic cause of intellectual disability. Early-onset Alzheimer's disease (AD) frequently develops in DS and is characterized by progressive memory loss and behavioral and psychological signs and symptoms of dementia (BPSD). Predicting and monitoring the progression of AD in DS is necessary to enable adaptive caretaking. OBJECTIVE: Reliable blood biomarkers that aid the prediction of AD are necessary, since cerebrospinal fluid sampling is rather burdensome, particularly for people with DS. Here, we investigate serum levels of eight biogenic amines and their metabolites in relation to dementia staging and probable BPSD items. METHODS: Using RP-HPLC with electrochemical detection, (nor)adrenergic (NA/A and MHPG), serotonergic (5-HT and 5-HIAA), and dopaminergic (DA, HVA, and DOPAC) compounds were quantified in the serum of DS subjects with established AD at baseline (n = 51), DS subjects without AD (n = 50), non-demented DS individuals that converted to AD over time (n = 50), and, finally, healthy non-DS controls (n = 22). RESULTS: Serum MHPG levels were significantly lower in demented and converted DS subjects (p < 0.0001) compared to non-demented DS individuals and healthy controls. Those subjects with MHPG levels below median had a more than tenfold increased risk of developing dementia. Furthermore, significant correlations were observed between monoaminergic serum values and various probable BPSD items within each DS group. CONCLUSION: Decreased serum MHPG levels show great potential as biomarker to monitor and predict conversion to AD in DS. Moreover, significant monoaminergic alterations related to probable BPSD items, suggesting that monoaminergic dysregulation is an underlying biological mechanism, and demonstrating the need to develop a validated rating scale for BPSD in DS.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Péptidos beta-Amiloides/sangre , Síndrome de Down/sangre , Metoxihidroxifenilglicol/sangre , Fragmentos de Péptidos/sangre , Enfermedad de Alzheimer/sangre , Biomarcadores/sangre , Progresión de la Enfermedad , Dopamina/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Norepinefrina/sangre
11.
J Theor Biol ; 363: 1-12, 2014 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-25109589

RESUMEN

The lodging of cereal crops due to high wind and rain is of considerable significance in many parts of the world, leading to major economic losses and yield reductions. In earlier papers the authors have developed a model of the lodging of winter wheat that identified the major parameters of the problem and enabled the relationship between root and stem lodging to be examined. It has formed the basis of a methodology used in the UK for guidance to farmers and agronomists on ways of reducing lodging risk. However the authors would be the first to acknowledge that there are limitations to the model that make it difficult to apply for a wide range of crops--particularly in the specification of the wind field and the root/soil interaction, and in allowing for stem lodging elsewhere than at the base of the stem. This paper thus describes the development of a generalised model that overcomes these shortcomings. After a discussion of the lodging phenomenon in general and a description of the earlier work, the basis of the new model is set out, based upon a mechanical model of the wind/plant/soil interactions that capture most of the important physical processes. The manner in which this model can be applied to clarify the nature of the lodging process and calculate lodging risk through a simple graphical formulation is discussed. In particular simple formulae are defined for lodging risk that are functions of a small number of dimensionless variables with identified physical meanings. The model is then applied to the lodging of wheat, oat and oilseed rape crops and considers the sensitivity of the risk calculations to uncertainties in the model parameters. In general it is suggested that the risk of lodging can be determined from very simple functions of dimensionless stem and root lodging velocities.


Asunto(s)
Productos Agrícolas/crecimiento & desarrollo , Modelos Biológicos , Tallos de la Planta/fisiología , Suelo/química , Fenómenos Biomecánicos , Simulación por Computador , Tallos de la Planta/anatomía & histología , Lluvia , Viento
12.
Br J Cancer ; 111(8): 1646-56, 2014 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-25137020

RESUMEN

BACKGROUND: Malignancy alters cellular complex lipid metabolism and membrane lipid composition and turnover. Here, we investigated whether tumorigenesis in cancer-derived prostate epithelial cell lines influences protein kinase C-linked turnover of ethanolamine phosphoglycerides (EtnPGs) and alters the pattern of ethanolamine (Etn) metabolites released to the medium. METHODS: Prostate epithelial cell lines P4E6, LNCaP and PC3 were models of prostate cancer (PCa). PNT2C2 and PNT1A were models of benign prostate epithelia. Cellular EtnPGs were labelled with [1-(3)H]-Etn hydrochloride. PKC was activated with phorbol ester (TPA) and inhibited with Ro31-8220 and GF109203X. D609 was used to inhibit PLD (phospholipase D). [(3)H]-labelled Etn metabolites were resolved by ion-exchange chromatography. Sodium oleate and mastoparan were tested as activators of PLD2. Phospholipase D activity was measured by a transphosphatidylation reaction. Cells were treated with ionomycin to raise intracellular Ca(2+) levels. RESULTS: Unstimulated cell lines release mainly Etn and glycerylphosphorylEtn (GPEtn) to the medium. Phorbol ester treatment over 3h increased Etn metabolite release from the metastatic PC3 cell line and the benign cell lines PNT2C2 and PNT1A but not from the tumour-derived cell lines P4E6 and LNCaP; this effect was blocked by Ro31-8220 and GF109203X as well as by D609, which inhibited PLD in a transphosphatidylation reaction. Only metastatic PC3 cells specifically upregulated Etn release in response to TPA treatment. Oleate and mastoparan increased GPEtn release from all cell lines at the expense of Etn. Ionomycin stimulated GPEtn release from benign PNT2C2 cells but not from cancer-derived cell lines P4E6 or PC3. Ethanolamine did not stimulate the proliferation of LNCaP or PC3 cell lines but decreased the uptake of choline (Cho). CONCLUSIONS: Only the metastatic basal PC3 cell line specifically increased the release of Etn on TPA treatment most probably by PKC activation of PLD1 and increased turnover of EtnPGs. The phosphatidic acid formed will maintain a cancer phenotype through the regulation of mTOR. Ethanolamine released from cells may reduce Cho uptake, regulating the membrane PtdEtn:PtdCho ratio and influencing the action of PtdEtn-binding proteins such as RKIP and the anti-apoptotic hPEBP4. The work highlights a difference between LNCaP cells used as a model of androgen-dependent early stage PCa and androgen-independent PC3 cells used to model later refractory stage disease.


Asunto(s)
Etanolamina/metabolismo , Metástasis de la Neoplasia , Próstata/efectos de los fármacos , Neoplasias de la Próstata/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Línea Celular , Línea Celular Tumoral , Activación Enzimática , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intercelular , Masculino , Péptidos/farmacología , Fosfolipasa D/metabolismo , Próstata/citología , Próstata/metabolismo , Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/patología , Venenos de Avispas/farmacología
13.
Br J Cancer ; 111(4): 716-25, 2014 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-24921920

RESUMEN

BACKGROUND: A frequent mechanism of acquired multidrug resistance in human cancers is overexpression of ATP-binding cassette transporters such as the Multi-Drug Resistance Protein 1 (MDR-1). Nutlin-3, an MDM2-p53 antagonist, has previously been reported to be a competitive MDR-1 inhibitor. METHODS: This study assessed whether the structurally diverse MDM2-p53 antagonists, MI-63, NDD0005, and RG7388 are also able to modulate MDR-1 function, particularly in p53 mutant neuroblastoma cells, using XTT-based cell viability assays, western blotting, and liquid chromatography-mass spectrometry analysis. RESULTS: Verapamil and the MDM2-p53 antagonists potentiated vincristine-mediated growth inhibition in a concentration-dependent manner when used in combination with high MDR-1-expressing p53 mutant neuroblastoma cell lines at concentrations that did not affect the viability of cells when given alone. Liquid chromatography-mass spectrometry analyses showed that verapamil, Nutlin-3, MI-63 and NDD0005, but not RG7388, led to increased intracellular levels of vincristine in high MDR-1-expressing cell lines. CONCLUSIONS: These results show that in addition to Nutlin-3, other structurally unrelated MDM2-p53 antagonists can also act as MDR-1 inhibitors and reverse MDR-1-mediated multidrug resistance in neuroblastoma cell lines in a p53-independent manner. These findings are important for future clinical trial design with MDM2-p53 antagonists when used in combination with agents that are MDR-1 substrates.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Antineoplásicos/farmacología , Resistencia a Antineoplásicos , Neuroblastoma/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-mdm2/antagonistas & inhibidores , Proteína p53 Supresora de Tumor/antagonistas & inhibidores , Subfamilia B de Transportador de Casetes de Unión a ATP , Antineoplásicos/metabolismo , Línea Celular Tumoral , Cisplatino/farmacología , Doxorrubicina/farmacología , Sinergismo Farmacológico , Humanos , Imidazoles/farmacología , Indoles/farmacología , Concentración 50 Inhibidora , Neuroblastoma/metabolismo , Piperazinas/farmacología , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Pirrolidinas/farmacología , Compuestos de Espiro/farmacología , Proteína p53 Supresora de Tumor/metabolismo , Verapamilo/farmacología , Vincristina/metabolismo , Vincristina/farmacología , para-Aminobenzoatos/farmacología
14.
Br J Cancer ; 110(8): 1977-84, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24556618

RESUMEN

BACKGROUND: Poly(ADP-ribose) polymerase-1 (PARP) inhibitors (PARPi) exploit tumour-specific defects in homologous recombination DNA repair and continuous dosing is most efficacious. Early clinical trial data with rucaparib suggested that it caused sustained PARP inhibition. Here we investigate the mechanism of this durable inhibition and potential exploitation. METHODS: Uptake and retention of rucaparib and persistence of PARP inhibition were determined by radiochemical and immunological assays in human cancer cell lines. The pharmacokinetics and pharmacodynamics of rucaparib were determined in tumour-bearing mice and the efficacy of different schedules of rucaparib was determined in mice bearing homologous recombination DNA repair-defective tumours. RESULTS: Rucaparib accumulation is carrier mediated (Km=8.4±1.2 µM, Vmax=469±22 pmol per 10(6) cells per 10 min), reaching steady-state levels >10 times higher than the extracellular concentration within 30 min. Rucaparib is retained in cells and inhibits PARP ≥50% for ≥72 h days after a 30-min pulse of 400 nM. In Capan-1 tumour-bearing mice rucaparib accumulated and was retained in the tumours, and PARP was inhibited for 7 days following a single dose of 10 mg kg(-1) i.p or 150 mg kg(-1) p.o. by 70% and 90%, respectively. Weekly dosing of 150 mg kg(-1) p.o once a week was as effective as 10 mg kg(-1) i.p daily for five days every week for 6 weeks in delaying Capan-1 tumour growth. CONCLUSIONS: Rucaparib accumulates and is retained in tumour cells and inhibits PARP for long periods such that weekly schedules have equivalent anticancer activity to daily dosing in a pre-clinical model, suggesting that clinical evaluation of alternative schedules of rucaparib should be considered.


Asunto(s)
Inhibidores Enzimáticos/administración & dosificación , Indoles/administración & dosificación , Poli(ADP-Ribosa) Polimerasas/genética , Animales , Línea Celular Tumoral , Reparación del ADN/efectos de los fármacos , Esquema de Medicación , Inhibidores Enzimáticos/sangre , Inhibidores Enzimáticos/farmacocinética , Recombinación Homóloga/efectos de los fármacos , Humanos , Indoles/sangre , Indoles/farmacocinética , Ratones , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Cell Death Differ ; 21(5): 761-73, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24464224

RESUMEN

Prostate cancer (CaP) is mostly composed of luminal-like differentiated cells, but contains a small subpopulation of basal cells (including stem-like cells), which can proliferate and differentiate into luminal-like cells. In cancers, CpG island hypermethylation has been associated with gene downregulation, but the causal relationship between the two phenomena is still debated. Here we clarify the origin and function of CpG island hypermethylation in CaP, in the context of a cancer cell hierarchy and epithelial differentiation, by analysis of separated basal and luminal cells from cancers. For a set of genes (including GSTP1) that are hypermethylated in CaP, gene downregulation is the result of cell differentiation and is not cancer specific. Hypermethylation is however seen in more differentiated cancer cells and is promoted by hyperproliferation. These genes are maintained as actively expressed and methylation-free in undifferentiated CaP cells, and their hypermethylation is not essential for either tumour development or expansion. We present evidence for the causes and the dynamics of CpG island hypermethylation in CaP, showing that, for a specific set of genes, promoter methylation is downstream of gene downregulation and is not a driver of gene repression, while gene repression is a result of tissue-specific differentiation.


Asunto(s)
Metilación de ADN , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Animales , Diferenciación Celular/genética , Procesos de Crecimiento Celular/genética , Regulación hacia Abajo , Células Epiteliales/patología , Xenoinjertos , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Pronóstico , Células Tumorales Cultivadas
16.
Acute Med ; 12(4): 232-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24364057

RESUMEN

The rates of liver disease in the UK are rising and hence more patients than ever are presenting to acute medical units with potentially life threatening sequelae. Early recognition and treatment of sepsis, kidney injury, bleeding and alcoholic hepatitis can significantly improve outcomes, but requires a comprehensive approach to assessment. This patient cohort often suffers from a perceived uniform poor prognosis, especially in alcohol related disease, but evidence for this is changing and reassessment of prognosis after 48 hours of organ support may be more accurate than that made 'at the front door'. This article summarises the most important complications of decompensated cirrhosis, their early management, and presents a targeted system of care: 'RING Liver'--Renal failure, Infection, Nutrition, Gastrointestinal bleeding and transit, Liver dysfunction/transplantation. Factors favouring transfer to tertiary units are also explored.


Asunto(s)
Manejo de la Enfermedad , Hepatitis Alcohólica/complicaciones , Cirrosis Hepática , Adulto , Progresión de la Enfermedad , Femenino , Hemorragia Gastrointestinal/etiología , Hospitalización , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/fisiopatología , Cirrosis Hepática/terapia , Masculino , Persona de Mediana Edad , Puntuaciones en la Disfunción de Órganos , Evaluación de Resultado en la Atención de Salud , Pronóstico , Insuficiencia Renal/etiología , Índice de Severidad de la Enfermedad , Centros de Atención Terciaria
17.
BMC Geriatr ; 13: 62, 2013 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-23782932

RESUMEN

BACKGROUND: Ongoing growth in health care expenditures and changing patterns in the demand for health care challenge societies worldwide. The Chronic Care Model (CCM), combined with classification for care needs based on Kaiser Permanente (KP) Triangle, may offer a suitable framework for change. The aim of the present study is to investigate the effectiveness of Embrace, a population-based model for integrated elderly care, regarding patient outcomes, service use, costs, and quality of care. METHODS/DESIGN: The CCM and the KP Triangle were translated to the Dutch setting and adapted to the full elderly population living in the community. A randomized controlled trial with balanced allocation was designed to test the effectiveness of Embrace. Eligible elderly persons are 75 years and older and enrolled with one of the participating general practitioner practices. Based on scores on the INTERMED-Elderly Self-Assessment and Groningen Frailty Indicator, participants will be stratified into one of three strata: (A) robust; (B) frail; and (C) complex care needs. Next, participants will be randomized per stratum to Embrace or care as usual. Embrace encompasses an Elderly Care Team per general practitioner practice, an Electronic Elderly Record System, decision support instruments, and a self-management support and prevention program - combined with care and support intensity levels increasing from stratum A to stratum C. Primary outcome variables are patient outcomes, service use, costs, and quality of care. Data will be collected at baseline, twelve months after starting date, and during the intervention period. DISCUSSION: This study could provide evidence for the effectiveness of Embrace. TRIAL REGISTRATION: The Netherlands National Trial Register NTR3039.


Asunto(s)
Costos de la Atención en Salud/normas , Atención al Paciente/economía , Atención al Paciente/normas , Calidad de la Atención de Salud/economía , Calidad de la Atención de Salud/normas , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Países Bajos/epidemiología , Atención al Paciente/estadística & datos numéricos , Calidad de la Atención de Salud/estadística & datos numéricos , Resultado del Tratamiento
18.
J Mech Behav Biomed Mater ; 20: 338-46, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23517774

RESUMEN

Properties of elasticity, hardness and viscosity are determined for the study of the visco-elastoplastic behavior of bones. The mechanical properties are compared in two upright sections of the bone due to their anisotropy. Besides, influence of hydration treatments leading to structural modifications of collagen and ground substance contents of bones on the mechanical properties is studied on a femoral cortical bovine bone. The treatments applied to the bone are used by forensic anthropologists to remove the soft tissue and modifying the hydration degree coupled to the collagen content. From instrumented indentation experiments, the hardness is characterized by the macrohardness and a hardness length-scale factor stating the hardness-load dependence. The elastic modulus results from the application of the methodology of Oliver and Pharr (1992). The coefficient of viscosity is deduced from a rheological model representing the indenter time-displacement observed under the application of a constant load. As a result, all the mechanical properties are found to be lower in the transverse section in an extent depending on the hydration treatment, i.e. the different values are located between 5% and 25% for the hardness around 0.5GPa, between 25% and 40% for the elastic modulus around 20GPa and between 2% and 35% for the coefficient of viscosity around 60GPa.s. Unexpectedly, the elastic modulus to coefficient of viscosity ratio is found to be independent on the hydration treatment.


Asunto(s)
Tejido Conectivo/química , Fémur/química , Fémur/fisiología , Pruebas de Dureza/métodos , Preservación de Órganos/métodos , Agua/química , Animales , Bovinos , Módulo de Elasticidad/fisiología , Dureza/fisiología , Técnicas In Vitro , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Viscosidad
19.
Expert Opin Pharmacother ; 14(4): 459-74, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23350964

RESUMEN

INTRODUCTION: Psychosis is a common and difficult to treat symptom in Alzheimer's disease (AD). It is a cause of diminished quality of life and caregiver distress. Atypical antipsychotics are frequently used for the treatment of dementia-related psychosis, despite FDA warnings because of increased mortality associated with the use of these medications in dementia patients. Aripiprazole is a newer atypical antipsychotic drug with partial agonist activity at dopamine receptors and antagonist activity at 5-HT(2A) receptors, with a low side-effect profile. AREAS COVERED: This descriptive review gives a short overview of the pathology and epidemiology of AD, including psychotic symptoms, and describes the mode of action of aripiprazole and results of preclinical studies. Finally, randomized controlled trials evaluating the use of aripiprazole in AD-related psychosis and agitation are discussed. Whenever relevant, meta-analytical data from literature are referred to. EXPERT OPINION: In randomized placebo-controlled clinical trials, aripiprazole shows modest efficacy in the treatment of AD-related psychosis. Neuropsychiatric symptoms alleviated were predominantly psychotic features and agitation. In individual trials, aripiprazole was generally well tolerated, serious side effects were seldom reported and included accidental injury and somnolence. Meta-analyses however demonstrated increased mortality as a class effect for atypical, but also for typical antipsychotics. No increased cardiovascular outcomes, cerebrovascular accidents, increased appetite or weight gain were demonstrated in meta-analyses for aripiprazole-treated patients with psychosis of dementia. Aripiprazole was found to induce sedation. Aripiprazole should only be used in selected patient populations resistant to non-pharmacological treatment with persisting or severe psychotic symptoms and/or agitation, and in which symptoms lead to significant morbidity, patient suffering and potential self-harm. The indication for continuing treatment should be revised regularly.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Antipsicóticos/uso terapéutico , Agonistas de Dopamina/uso terapéutico , Piperazinas/uso terapéutico , Trastornos Psicóticos/tratamiento farmacológico , Quinolonas/uso terapéutico , Antagonistas del Receptor de Serotonina 5-HT2/uso terapéutico , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/psicología , Antipsicóticos/administración & dosificación , Antipsicóticos/efectos adversos , Aripiprazol , Agonistas de Dopamina/administración & dosificación , Agonistas de Dopamina/efectos adversos , Humanos , Metaanálisis como Asunto , Uso Fuera de lo Indicado , Piperazinas/administración & dosificación , Piperazinas/efectos adversos , Trastornos Psicóticos/epidemiología , Trastornos Psicóticos/metabolismo , Quinolonas/administración & dosificación , Quinolonas/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Receptor de Serotonina 5-HT2A/metabolismo , Receptores Dopaminérgicos/metabolismo , Antagonistas del Receptor de Serotonina 5-HT2/administración & dosificación , Antagonistas del Receptor de Serotonina 5-HT2/efectos adversos
20.
Aliment Pharmacol Ther ; 37(2): 174-82, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23157692

RESUMEN

BACKGROUND: Increasing numbers of patients are being admitted to hospital with decompensated chronic liver disease in the UK. A significant proportion will develop complicating extra-hepatic organ dysfunction, but the selection of those who should be admitted to intensive care is complex and challenging. Alcohol-related liver disease also presents complex ethical dilemmas. AIM: To review recent survival analyses and explore differences in secondary and tertiary care; to highlight strengths and weaknesses of prognostic models, therapeutic advances and shifts in prognostic expectation. We also aim to explore the ethical challenges presented by addiction and self-injury in an area of limited resource. METHODS: We searched PubMed for articles discussing 'cirrhosis', 'prognosis', 'critical illness', 'organ failure', 'renal failure', 'alcohol', 'ethics' and 'addiction'. We also explored particular ethical dilemmas encountered by the authors and colleagues. RESULTS: Prognosis has improved in many cirrhotic complications and historically poor outcomes in tertiary care may reflect a more complex patient cohort. Previously 'untreatable' complications are now being managed successfully. Estimates of survival are more accurate after a 48-h period of supportive care. Physicians are not best placed to make judgments with regard to deservingness, moral responsibility, rationing and access to organ support in cases of acute deterioration related to alcoholism, and the case for denying support must be made on purely medical grounds. CONCLUSIONS: An early, aggressive approach to organ support is justified. Further discussions between hepatologists and critical care physicians are required to determine acceptable burden-to-benefit ratios for prolonged intensive care support in young alcoholic patients.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Alcoholismo/complicaciones , Cuidados Críticos/ética , Unidades de Cuidados Intensivos/ética , Cirrosis Hepática/terapia , Insuficiencia Multiorgánica/terapia , Actitud del Personal de Salud , Cuidados Críticos/normas , Humanos , Unidades de Cuidados Intensivos/normas , Índice de Severidad de la Enfermedad , Análisis de Supervivencia
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