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

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Development ; 148(14)2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34184027

RESUMEN

Bone morphogenetic protein (BMP) signaling is required for early forebrain development and cortical formation. How the endogenous modulators of BMP signaling regulate the structural and functional maturation of the developing brain remains unclear. Here, we show that expression of the BMP antagonist Grem1 marks committed layer V and VI glutamatergic neurons in the embryonic mouse brain. Lineage tracing of Grem1-expressing cells in the embryonic brain was examined by administration of tamoxifen to pregnant Grem1creERT; Rosa26LSLTdtomato mice at 13.5 days post coitum (dpc), followed by collection of embryos later in gestation. In addition, at 14.5 dpc, bulk mRNA-seq analysis of differentially expressed transcripts between FACS-sorted Grem1-positive and -negative cells was performed. We also generated Emx1-cre-mediated Grem1 conditional knockout mice (Emx1-Cre;Grem1flox/flox) in which the Grem1 gene was deleted specifically in the dorsal telencephalon. Grem1Emx1cKO animals had reduced cortical thickness, especially layers V and VI, and impaired motor balance and fear sensitivity compared with littermate controls. This study has revealed new roles for Grem1 in the structural and functional maturation of the developing cortex.


Asunto(s)
Proteína Morfogenética Ósea 1/antagonistas & inhibidores , Encéfalo/fisiología , Miedo/fisiología , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Neuronas Motoras/metabolismo , Transducción de Señal , Animales , Conducta Animal , Proteína Morfogenética Ósea 1/genética , Encéfalo/embriología , Diferenciación Celular , Proliferación Celular , Femenino , Regulación del Desarrollo de la Expresión Génica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neuronas/fisiología , Células Madre , Transcriptoma
2.
J Neurosci Res ; 100(2): 653-669, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34882833

RESUMEN

The role of increased brain inflammation in the development of neurodegenerative diseases is unclear. Here, we have compared cytokine changes in normal aging, motor neurone disease (MND), and Alzheimer's disease (AD). After an initial analysis, six candidate cytokines, interleukin (IL)- 4, 5, 6, 10, macrophage inhibitory protein (MIP)-1α, and fibroblast growth factor (FGF)-2, showing greatest changes were assayed in postmortem frozen human superior frontal gyri (n = 12) of AD patients, aging and young adult controls along with the precentral gyrus (n = 12) of MND patients. Healthy aging was associated with decreased anti-inflammatory IL-10 and FGF-2 levels. AD prefrontal cortex was associated with increased levels of IL-4, IL-5, and FGF-2, with the largest increase seen for FGF-2. Notwithstanding differences in the specific frontal lobe gyrus sampled, MND patients' primary motor cortex (precentral gyrus) was associated with increased levels of IL-5, IL-6, IL-10, and FGF-2 compared to the aging prefrontal cortex (superior frontal gyrus). Immunocytochemistry showed that FGF-2 is expressed in neurons, astrocytes, and microglia in normal aging prefrontal cortex, AD prefrontal cortex, and MND motor cortex. We report that healthy aging and age-related neurodegenerative diseases have different cortical inflammatory signatures that are characterized by increased levels of anti-inflammatory cytokines and call into question the view that increased inflammation underlies the development of age-related neurodegenerative diseases.


Asunto(s)
Envejecimiento , Enfermedad de Alzheimer , Citocinas , Enfermedad de la Neurona Motora , Envejecimiento/metabolismo , Enfermedad de Alzheimer/metabolismo , Astrocitos/metabolismo , Citocinas/metabolismo , Humanos , Inflamación/metabolismo , Microglía/metabolismo , Enfermedad de la Neurona Motora/metabolismo , Adulto Joven
3.
Intern Med J ; 52(2): 315-317, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35187820

RESUMEN

Automated information extraction might be able to assist with the collection of stroke key performance indicators (KPI). The feasibility of using natural language processing for classification-based KPI and datetime field extraction was assessed. Using free-text discharge summaries, random forest models achieved high levels of performance in classification tasks (area under the receiver operator curve 0.95-1.00). The datetime field extraction method was successful in 29 of 43 (67.4%) cases. Further studies are indicated.


Asunto(s)
Aprendizaje Automático , Accidente Cerebrovascular , Registros Electrónicos de Salud , Humanos , Almacenamiento y Recuperación de la Información , Procesamiento de Lenguaje Natural , Proyectos Piloto , Accidente Cerebrovascular/terapia
4.
Intern Med J ; 52(2): 176-185, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33094899

RESUMEN

Length of stay (LOS) estimates are important for patients, doctors and hospital administrators. However, making accurate estimates of LOS can be difficult for medical patients. This review was conducted with the aim of identifying and assessing previous studies on the application of machine learning to the prediction of total hospital inpatient LOS for medical patients. A review of machine learning in the prediction of total hospital LOS for medical inpatients was conducted using the databases PubMed, EMBASE and Web of Science. Of the 673 publications returned by the initial search, 21 articles met inclusion criteria. Of these articles the most commonly represented medical specialty was cardiology. Studies were also identified that had specifically evaluated machine learning LOS prediction in patients with diabetes and tuberculosis. The performance of the machine learning models in the identified studies varied significantly depending on factors including differing input datasets and different LOS thresholds and outcome metrics. Common methodological shortcomings included a lack of reporting of patient demographics and lack of reporting of clinical details of included patients. The variable performance reported by the studies identified in this review supports the need for further research of the utility of machine learning in the prediction of total inpatient LOS in medical patients. Future studies should follow and report a more standardised methodology to better assess performance and to allow replication and validation. In particular, prospective validation studies and studies assessing the clinical impact of such machine learning models would be beneficial.


Asunto(s)
Pacientes Internos , Aprendizaje Automático , Bases de Datos Factuales , Predicción , Humanos , Tiempo de Internación
5.
Value Health ; 22(2): 254-262, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30711072

RESUMEN

OBJECTIVES: To examine economic evaluation studies of stem cell therapies (SCTs) in neurological disorders and to provide an overview of the quality of the economic evidence available on this topic. METHODS: The review examined studies that performed an economic evaluation of the use of stem cells in adult patients with neurological diseases and that were published in English during the period 2007 to 2017. Data analyzed and reported included study population, disease indication, main analytical approaches for the economic analysis and perspective, key assumptions made or tested in sensitivity analyses, cost outcomes, estimates of incremental cost effectiveness, and approaches to quantifying decision uncertainty. RESULTS: A total of three studies reporting on the findings of the economic evaluation of the use of SCT in stroke, Parkinson disease, and secondary progressive multiple sclerosis, respectively, were identified. All three studies conducted a cost-utility analysis using decision-analytic models and reported an incremental cost per quality-adjusted life-years gained (incremental cost-effectiveness ratio) versus standard care. These studies reported meaningful cost savings in stroke, Parkinson disease, and secondary progressive multiple sclerosis in the base-case scenarios. CONCLUSIONS: Despite significant progress in clinical research in the use of SCT in neurological diseases, economic evaluation of these therapies is still at a nascent stage. Given the early stage of research inputs (clinical and cost outcomes data) into the models per se, further research is urgently needed to enable meaningful assessment of the cost effectiveness of these advanced therapies and to ensure sustainable access for population groups most likely to benefit in clinical practice.


Asunto(s)
Análisis Costo-Beneficio/métodos , Enfermedades del Sistema Nervioso/economía , Enfermedades del Sistema Nervioso/terapia , Trasplante de Células Madre/economía , Humanos , Enfermedades del Sistema Nervioso/epidemiología , Trasplante de Células Madre/métodos , Evaluación de la Tecnología Biomédica/economía , Evaluación de la Tecnología Biomédica/métodos
6.
BMC Neurol ; 19(1): 96, 2019 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-31078139

RESUMEN

BACKGROUND: Post-stroke lower limb spasticity (PSLLS) has a prevalence of 28-37%. PSLLS can cause difficulty in walking and reduce quality of life (QOL). Post stroke spasticity impairs the ability to intervene to improve walking ability. Botulinum Toxin A (BT) is an effective intervention for focal spasticity, but its use is currently restricted in many countries by their reimbursement system stating that the evidence for improvement in walking and quality of life (QOL) is not robust for treatment in the lower limb. This randomized control trial (RCT) will investigate the effectiveness of BT in modifying spasticity, and improving functioning (mobility, walking, activities of daily living (ADL's) and QOL. METHODS/DESIGN: A double-blind placebo-controlled trial injection will assess the effect of BT compared with a placebo (normal saline) in a sample of n = 94 patients. Following treatment of spasticity measured by Modified Ashworth Scale (MAS), the primary outcome of gait velocity will be measured by i) Gait Rite (Electronic Walkway); ii) walking by 2 Min Walk Test; iii) balance by Berg Balance Scale; mobility by iv) Timed Up and Go (TUG); v) lower limb function by ABILICO; vi) patient related goal by Goal Attainment Scale (GAS); vii) QOL by SF 12 (Rand version); viii) activities of daily living by the Functional Autonomy Measurement System (SMAF). There will be an associated health economic analysis. DISCUSSION: The study methodology is based on our systematic review 2026 studies, which concluded the evidence for improving mobility following use of BT to reduce spasticity was not robust. The results of this study could establish the use of BT in improving gait and lower limb function in PSLLS. This study could provide the evidence needed for reimbursement schemes to consider and changes to its funding policy for BT in PSLLS. TRIAL REGISTRATION: The trial is registered with the Australia New Zealand Clinical Trails Registry (ANZCTR)- ANZCTRN12617001603303 . Registered 07/12/2017.


Asunto(s)
Toxinas Botulínicas Tipo A/uso terapéutico , Espasticidad Muscular/tratamiento farmacológico , Fármacos Neuromusculares/uso terapéutico , Calidad de Vida , Accidente Cerebrovascular/complicaciones , Actividades Cotidianas , Anciano , Método Doble Ciego , Femenino , Humanos , Extremidad Inferior/fisiopatología , Masculino , Persona de Mediana Edad , Espasticidad Muscular/etiología , Proyectos de Investigación , Caminata
7.
Health Expect ; 22(5): 1069-1077, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31332894

RESUMEN

BACKGROUND: Stem cell research holds the potential for a paradigm shift in the management of diseases such as stroke. Patient and public involvement in research (PPIR) can bring a focus to issues of clinical relevance and accelerate translation to real-world clinical practice. OBJECTIVE: A qualitative thematic analysis of the perspectives of stroke survivors regarding the conduct and design aspects of a proposed phase I clinical cell therapy study in stroke. DESIGN: Twelve stroke survivors were purposively recruited in July 2016-August 2017 and participated in semi-structured, face-to-face interviews for input into the design of a proposed phase I clinical study of autologous dental pulp stem cells. Concurrent thematic analysis was conducted until data saturation was achieved. DISCUSSION AND CONCLUSIONS: Participants conveyed that the most relevant outcomes to them were regaining participation, decreased dependence on caregivers and improvement in cognition, memory, mood, pain and fatigue. The perception of risk vs. benefit was likely influenced by the time elapsed since stroke, with participants being more willing to accept a higher level of risk early in the post-stroke disease course. They believed that all stroke survivors should be given an opportunity to participate in research, irrespective of their cognitive capacity. A relatively small sample population of 12 stroke survivors was studied as thematic saturation was achieved. PERSPECTIVES study applied principles of PPIR to early-phase cell research. Incorporation of outcomes relevant to patients' need within the study design is critical to generate data that will enable personalized application of regenerative medicine in stroke.


Asunto(s)
Isquemia Encefálica/terapia , Trasplante de Células Madre/psicología , Accidente Cerebrovascular/psicología , Sobrevivientes/psicología , Adulto , Anciano , Anciano de 80 o más Años , Ensayos Clínicos Fase I como Asunto , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Participación del Paciente , Medición de Riesgo , Trasplante de Células Madre/métodos , Accidente Cerebrovascular/terapia
8.
Mol Cell Neurosci ; 88: 201-211, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29427776

RESUMEN

Hyperphosphorylation of tau is one of the main hallmarks for Alzheimer's disease (AD) and many other tauopathies. Norepinephrine (NE), a stress-related hormone and 17-ß-estradiol (E2) thought to influence tau phosphorylation (p-tau) and AD pathology. The controversy around the impact of NE and E2 requires further clarification. Moreover, the combination effect of physiological and psychological stress and estrogen alteration during menopause, which affect p-tau, has not been addressed. Exposure to E2 is believed to reduce NE release, however, the link between these two hormones and AD at cellular level was also remained unknown. Here, we examined whether NE and E2 treatment of differentiated SH-SY5Y cells affected tau phosphorylation. The involvement of adenosine monophosphate kinase protein kinase (AMPK) and target of Rapamycin (mTOR) as the possible mechanisms, underlying this effect was also investigated. Subsequent to SH-SY5Y differentiation to mature neurons, we treated the cells with NE, E2 and NE plus E2 in presence and absence of Compound C and Rapamycin. Cell viability was not affected by our treatment while our Western blot and immunofluorescent findings showed that exposure to NE and E2 separately, and in combination enhanced p-tau (Ser396) and (Ser262)/tau but not (Ser202/Thr205)/tau. Blocking AMPK by Compound C reduced p-tau (Ser396) and (Ser262), while GSK-3ß and PP2A activities were remained unchanged. We also found that blocking mTOR by Rapamycin did not change increased p-tau (Ser396) and (Ser262) due to NE + E2 treatment. Collectively, our results suggested that tau hyperphosphorylation due to exposure to NE/E2 was mediated by AMPK, the main energy regulator of cells during stress with no significant involvement of mTOR, GSK-3ß and PP2A.


Asunto(s)
Adenilato Quinasa/metabolismo , Diferenciación Celular/efectos de los fármacos , Norepinefrina/farmacología , Transducción de Señal/efectos de los fármacos , Proteínas tau/efectos de los fármacos , Adenosina Monofosfato/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Estradiol/farmacología , Glucógeno Sintasa Quinasa 3/metabolismo , Humanos , Fosforilación/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Proteínas tau/metabolismo
9.
Angiogenesis ; 19(4): 463-86, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27338829

RESUMEN

Desmogleins (DSG) are a family of cadherin adhesion proteins that were first identified in desmosomes and provide cardiomyocytes and epithelial cells with the junctional stability to tolerate mechanical stress. However, one member of this family, DSG2, is emerging as a protein with additional biological functions on a broader range of cells. Here we reveal that DSG2 is expressed by non-desmosome-forming human endothelial progenitor cells as well as their mature counterparts [endothelial cells (ECs)] in human tissue from healthy individuals and cancer patients. Analysis of normal blood and bone marrow showed that DSG2 is also expressed by CD34(+)CD45(dim) hematopoietic progenitor cells. An inability to detect other desmosomal components, i.e., DSG1, DSG3 and desmocollin (DSC)2/3, on these cells supports a solitary role for DSG2 outside of desmosomes. Functionally, we show that CD34(+)CD45(dim)DSG2(+) progenitor cells are multi-potent and pro-angiogenic in vitro. Using a 'knockout-first' approach, we generated a Dsg2 loss-of-function strain of mice (Dsg2 (lo/lo)) and observed that, in response to reduced levels of Dsg2: (i) CD31(+) ECs in the pancreas are hypertrophic and exhibit altered morphology, (ii) bone marrow-derived endothelial colony formation is impaired, (iii) ex vivo vascular sprouting from aortic rings is reduced, and (iv) vessel formation in vitro and in vivo is attenuated. Finally, knockdown of DSG2 in a human bone marrow EC line reveals a reduction in an in vitro angiogenesis assay as well as relocalisation of actin and VE-cadherin away from the cell junctions, reduced cell-cell adhesion and increased invasive properties by these cells. In summary, we have identified DSG2 expression in distinct progenitor cell subpopulations and show that, independent from its classical function as a component of desmosomes, this cadherin also plays a critical role in the vasculature.


Asunto(s)
Desmogleína 2/metabolismo , Células Endoteliales/metabolismo , Neovascularización Fisiológica , Animales , Diferenciación Celular , Células Cultivadas , Desmogleína 2/deficiencia , Desmogleína 2/genética , Células Endoteliales/citología , Femenino , Técnicas de Silenciamiento del Gen , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Modelos Animales , Neovascularización Fisiológica/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/genética
10.
Eur J Neurosci ; 44(3): 1987-97, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27177932

RESUMEN

Abnormal tau phosphorylation (p-tau) has been shown after hypoxic damage to the brain associated with traumatic brain injury and stroke. As the level of p-tau is controlled by Glycogen Synthase Kinase (GSK)-3ß, Protein Phosphatase 2A (PP2A) and Adenosine Monophosphate Kinase (AMPK), different activity levels of these enzymes could be involved in tau phosphorylation following ischaemia. This study assessed the effects of global brain ischaemia/reperfusion on the immediate status of p-tau in a rat model of cardiac arrest (CA) followed by cardiopulmonary resuscitation (CPR). We reported an early dephosphorylation of tau at its AMPK sensitive residues, Ser(396) and Ser(262) after 2 min of ischaemia, which did not recover during the first two hours of reperfusion, while the tau phosphorylation at GSK-3ß sensitive but AMPK insensitive residues, Ser(202) /Thr(205) (AT8), as well as the total amount of tau remained unchanged. Our data showed no alteration in the activities of GSK-3ß and PP2A during similar episodes of ischaemia of up to 8 min and reperfusion of up to 2 h, and 4 weeks recovery. Dephosphorylation of AMPK followed the same pattern as tau dephosphorylation during ischaemia/reperfusion. Catalase, another AMPK downstream substrate also showed a similar pattern of decline to p-AMPK, in ischaemic/reperfusion groups. This suggests the involvement of AMPK in changing the p-tau levels, indicating that tau dephosphorylation following ischaemia is not dependent on GSK-3ß or PP2A activity, but is associated with AMPK dephosphorylation. We propose that a reduction in AMPK activity is a possible early mechanism responsible for tau dephosphorylation.


Asunto(s)
Isquemia Encefálica/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Paro Cardíaco/metabolismo , Proteínas Quinasas/metabolismo , Proteína Fosfatasa 2/metabolismo , Daño por Reperfusión/metabolismo , Proteínas tau/metabolismo , Quinasas de la Proteína-Quinasa Activada por el AMP , Animales , Isquemia Encefálica/etiología , Catalasa/metabolismo , Femenino , Paro Cardíaco/complicaciones , Fosforilación , Procesamiento Proteico-Postraduccional , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/etiología
11.
Stroke ; 46(11): 3042-7, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26443828

RESUMEN

BACKGROUND AND PURPOSE: Evidence from epidemiological studies points to differences in factors predisposing to stroke by age and sex. Whether these arise because of different genetic influences remained untested. Here, we use data from 4 genome-wide association data sets to study the relationship between genetic influence on stroke with both age and sex. METHODS: Using genomic-relatedness-matrix restricted maximum likelihood methods, we performed 4 analyses: (1) we calculated the genetic correlation between groups divided by age and (2) by sex, (3) we calculated the heritability of age-at-stroke-onset, and (4) we evaluated the evidence that heritability of stroke is greater in women than in men. RESULTS: We found that genetic factors influence age at stroke onset (h2 [SE]=18.0 [6.8]; P=0.0038), with a trend toward a stronger influence in women (women: h2 [SE]=21.6 [3.5]; Men: h2 [SE]=13.9 [2.8]). Although a moderate proportion of genetic factors was shared between sexes (rG [SE]=0.68 [0.16]) and between younger and older cases (rG [SE]=0.70 [0.17]), there was evidence to suggest that there are genetic susceptibility factors that are specific to sex (P=0.037) and to younger or older groups (P=0.056), particularly for women (P=0.0068). Finally, we found a trend toward higher heritability of stroke in women although this was not significantly greater than in men (P=0.084). CONCLUSIONS: Our results indicate that there are genetic factors that are either unique to or have a different effect between younger and older age groups and between women and men. Performing large, well-powered genome-wide association study analyses in these groups is likely to uncover further associations.


Asunto(s)
Envejecimiento/genética , Isquemia Encefálica/genética , Predisposición Genética a la Enfermedad/genética , Caracteres Sexuales , Accidente Cerebrovascular/genética , Adulto , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/epidemiología , Estudios de Cohortes , Femenino , Predisposición Genética a la Enfermedad/epidemiología , Estudio de Asociación del Genoma Completo/métodos , Humanos , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología
12.
BMC Neurol ; 15: 109, 2015 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-26162759

RESUMEN

BACKGROUND: Evidence in animal stroke models suggests that neuroplasticity takes place maximally in a specific time window after an ischaemic lesion, which may coincide with the optimal time to intervene with rehabilitation. The aim of this study is to investigate neurophysiological evidence for a "critical window" of enhanced neuroplasticity in patients following ischaemic stroke, and establish its duration. We will also investigate changes in cortical inhibition following stroke, and the influence this has on functional recovery. METHODS/DESIGN: We will recruit participants recently admitted to the Stroke Unit of major metropolitan hospitals who have had a stroke and can provide informed consent. Participants will be excluded if they have any contraindications to Transcranial Magnetic Stimulation. We will compare neurophysiological outcomes in an age-matched healthy control group. We conservatively hypothesise a 5% increase in neuroplasticity at the optimal timing following stroke, compared to control participants, and require 43 patients following stroke to detect a significant difference with 80% power. The primary outcome is the change in the motor evoked potential (MEP) amplitude in a hand muscle, after the administration of a plasticity-inducing paradigm to the affected hemisphere. Secondary outcomes include measures of cortical excitability, intracortical inhibition and arm function. DISCUSSION: The data from this trial will clarify whether there is a critical window for neuroplastic change in the brain following stroke. If so, intensive rehabilitation during this period could be more effective, reducing long-term disability and the cost burden of stroke.


Asunto(s)
Potenciales Evocados Motores/fisiología , Rehabilitación de Accidente Cerebrovascular , Estimulación Magnética Transcraneal/métodos , Adulto , Mano/fisiopatología , Humanos , Músculo Esquelético/fisiopatología , Plasticidad Neuronal , Recuperación de la Función/fisiología
13.
Int J Mol Sci ; 16(12): 29011-28, 2015 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-26690124

RESUMEN

Stroke is one of the leading causes of death and adult disability in the world. Although many molecules have been documented to have a neuroprotective effect, the majority of these molecules failed to improve the neurological outcomes for patients with brain ischemia. It has been proposed that neuroprotection alone may, in fact, not be adequate for improving the prognosis of ischemic stroke. Neuroprotectants that can regulate other processes which occur in the brain during ischemia could potentially be targets for the development of effective therapeutic interventions in stroke. Neuronal Per-Arnt-Sim domain protein 4 (Npas4) is an activity-dependent transcription factor whose expression is induced in various brain insults, including cerebral ischemia. It has been shown that Npas4 plays an important role in protecting neurons against many types of neurodegenerative insult. Recently, it was demonstrated that Npas4 indeed has a neuroprotective role in ischemic stroke and that Npas4 might be involved in modulating the cell death pathway and inflammatory response. In this review, we summarize the current knowledge of the roles that Npas4 may play in neuroinflammation and ischemia. Understanding how ischemic lesion size in stroke may be reduced through modulation of Npas4-dependent apoptotic and inflammatory pathways could lead to the development of new stroke therapies.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Encéfalo/patología , Neuronas/patología , Animales , Apoptosis , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Encéfalo/citología , Encéfalo/metabolismo , Isquemia Encefálica/genética , Regulación de la Expresión Génica , Humanos , Inflamación/genética , Inflamación/metabolismo , Neuronas/citología , Neuronas/metabolismo
14.
Stroke ; 45(4): 1064-8, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24569814

RESUMEN

BACKGROUND AND PURPOSE: Studies in rodent models suggest that upregulating angiopoietin-1 (Angpt1) improves stroke outcomes. The aims of this study were to assess the association of plasma Angpt1 with stroke occurrence and outcome. METHODS: Plasma Angpt1 was measured in 336 patients who had experienced a recent stroke and 321 healthy controls with no stroke history. Patients with stroke (n=285) were reassessed at 3 months and plasma Angpt1 concentration on admission compared between those with severe and minor disability as assessed by the modified Rankin scale. In a separate cohort of 4032 community-acquired older men prospectively followed for a minimum of 6 years, the association of plasma Angpt1 with stroke incidence was examined. RESULTS: Median plasma Angpt1 was 3-fold lower in patients who had experienced a recent stroke (6.42, interquartile range, 4.26-9.53 compared with 17.36; interquartile range, 14.01-22.46 ng/mL; P<0.001) and remained associated with stroke after adjustment for other risk factors. Plasma Angpt1 concentrations on admission were lower in patients who had severe disability or died at 3 months (median, 5.52; interquartile range, 3.81-8.75 ng/mL for modified Rankin scale 3-6; n=91) compared with those with minor disability (median, 7.04; interquartile range, 4.75-9.92 ng/mL for modified Rankin scale 0-2; n=194), P=0.012, and remained negatively associated with severe disability or death after adjusting for other risk factors. Plasma Angpt1 was not predictive of stroke incidence in community-dwelling older men. CONCLUSIONS: Plasma Angpt1 concentrations are low after ischemic stroke particularly in patients with poor stroke outcomes at 3 months. Interventions effective at upregulating Angpt1 could potentially improve stroke outcomes.


Asunto(s)
Angiopoyetina 1/sangre , Isquemia Encefálica/sangre , Isquemia Encefálica/mortalidad , Evaluación de la Discapacidad , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/mortalidad , Anciano , Biomarcadores/sangre , Isquemia Encefálica/clasificación , Estudios de Casos y Controles , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/clasificación
15.
Stroke ; 45(12): 3508-13, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25352485

RESUMEN

BACKGROUND AND PURPOSE: Epidemiological studies show strong associations between kidney dysfunction and risk of ischemic stroke (IS), the mechanisms of which are incompletely understood. We investigated whether these associations may reflect shared heritability because of a common polygenic basis and whether this differed for IS subtypes. METHODS: Polygenic models were derived using genome-wide association studies meta-analysis results for 3 kidney traits: estimated glomerular filtration rate using serum creatinine (eGFRcrea: n=73 998), eGFR using cystatin C (eGFRcys: n=22 937), and urinary albumin to creatinine ratio (n=31 580). For each, single nucleotide polymorphisms passing 10 P value thresholds were used to form profile scores in 4561 IS cases and 7094 controls from the United Kingdom, Germany, and Australia. Scores were tested for association with IS and its 3 aetiological subtypes: large artery atherosclerosis, cardioembolism, and small vessel disease. RESULTS: Polygenic scores correlating with higher eGFRcrea were associated with reduced risk of large artery atherosclerosis, with 5 scores reaching P<0.05 (peak P=0.004) and all showing the epidemiologically expected direction of effect. A similar pattern was observed for polygenic scores reflecting higher urinary albumin to creatinine ratio, of which 3 associated with large artery atherosclerosis (peak P=0.01) and all showed the expected directional association. One urinary albumin to creatinine ratio-based score also associated with small vessel disease (P=0.03). The global pattern of results was unlikely to have occurred by chance (P=0.02). CONCLUSIONS: This study suggests possible polygenic correlation between renal dysfunction and IS. The shared genetic components may be specific to stroke subtypes, particularly large artery atherosclerotic stroke. Further study of the genetic relationships between these disorders seems merited.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Enfermedades Renales/genética , Accidente Cerebrovascular/genética , Albuminuria/complicaciones , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Enfermedades Renales/fisiopatología , Polimorfismo de Nucleótido Simple
16.
Stem Cells ; 31(6): 1040-3, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23390084

RESUMEN

Stroke, a debilitating brain insult, afflicts millions of individuals globally each year. In the last decade, researchers have investigated cell-based therapy as an alternative strategy to improve neurological outcome following stroke. This concise review critically examines preclinical reports using human adult and fetal stem/progenitor cells in rodent models of ischemic stroke. As we enter the second decade of study, we should aim to optimize our collective likelihood to translational success for stroke victims worldwide. We advocate international consensus recommendations be developed for future preclinical research.


Asunto(s)
Isquemia Encefálica/terapia , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Células Madre/citología , Accidente Cerebrovascular/terapia , Animales , Modelos Animales de Enfermedad , Humanos
17.
Nicotine Tob Res ; 16(11): 1495-502, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25031315

RESUMEN

INTRODUCTION: Inpatient medical settings offer an opportunistic environment for initiating smoking cessation interventions to patients reflecting on their health. Current evidence has shown the superior efficacy of varenicline tartrate (VT) for smoking cessation compared with other tobacco cessation therapies; however, recent evidence also has highlighted concerns about the safety and tolerability of VT. Given these apprehensions, we aimed to evaluate the safety and effectiveness of VT plus quitline-counseling compared to quitline-counseling alone in the inpatient medical setting. METHODS: Adult patients (n = 392, 20-75 years) admitted with a smoking-related illnesses to 3 hospitals were randomized to receive either 12 weeks of varenicline tartrate (titrated from 0.5mg daily to 1mg twice daily) plus quitline-counseling (VT+C), (n = 196) or quitline-counseling alone (n = 196). RESULTS: VT was well tolerated in the inpatient setting among subjects admitted with acute smoking-related illnesses (mean age 52.8±2.89 and 53.7±2.77 years in the VT+C and counseling alone groups, respectively). The most common self-reported adverse event during the 12-week treatment phase was nausea (16.3% in the VT+C group compared with 1.5% in the counseling alone group). Thirteen deaths occurred during the study period (n = 6 were in the VT+C arm compared with n = 7 in the counseling alone arm). All of these subjects had known comorbidities or developed underlying comorbidities. CONCLUSIONS: VT appears to be a safe and well-tolerated opportunistic treatment for inpatient smokers who have related chronic disease. Based on the proven efficacy of varenicline from outpatient studies and our recent inpatient evidence, we suggest it be considered as part of standard care in the hospital setting.


Asunto(s)
Benzazepinas/administración & dosificación , Consejo/métodos , Hospitalización , Agonistas Nicotínicos/administración & dosificación , Quinoxalinas/administración & dosificación , Cese del Hábito de Fumar/métodos , Fumar/terapia , Adulto , Anciano , Benzazepinas/efectos adversos , Femenino , Cefalea/inducido químicamente , Humanos , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Agonistas Nicotínicos/efectos adversos , Quinoxalinas/efectos adversos , Fumar/psicología , Cese del Hábito de Fumar/psicología , Resultado del Tratamiento , Vareniclina , Adulto Joven
18.
Stem Cell Rev Rep ; 20(3): 797-815, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38316679

RESUMEN

Stem cell-based therapy is a potential alternative strategy for brain repair, with neural stem cells (NSC) presenting as the most promising candidates. Obtaining sufficient quantities of NSC for clinical applications is challenging, therefore alternative cell types, such as neural crest-derived dental pulp stem cells (DPSC), may be considered. Human DPSC possess neurogenic potential, exerting positive effects in the damaged brain through paracrine effects. However, a method for conversion of DPSC into NSC has yet to be developed. Here, overexpression of octamer-binding transcription factor 4 (OCT4) in combination with neural inductive conditions was used to reprogram human DPSC along the neural lineage. The reprogrammed DPSC demonstrated a neuronal-like phenotype, with increased expression levels of neural markers, limited capacity for sphere formation, and enhanced neuronal but not glial differentiation. Transcriptomic analysis further highlighted the expression of genes associated with neural and neuronal functions. In vivo analysis using a developmental avian model showed that implanted DPSC survived in the developing central nervous system and respond to endogenous signals, displaying neuronal phenotypes. Therefore, OCT4 enhances the neural potential of DPSC, which exhibited characteristics aligning with neuronal progenitors. This method can be used to standardise DPSC neural induction and provide an alternative source of neural cell types.


Asunto(s)
Pulpa Dental , Células Madre , Humanos , Diferenciación Celular , Factor de Transcripción 4/metabolismo , Neurogénesis
19.
Eur J Neurosci ; 37(11): 1875-84, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23431968

RESUMEN

The neuronal Per-Arnt-Sim domain protein 4 (Npas4) is an important transcriptional regulator of synaptic plasticity and cognition. The present study characterises the in vivo neuroanatomical expression pattern of the Npas4 protein in a rat model of focal cerebral ischemia. Animals were subjected to unilateral middle cerebral artery occlusion for 2 h, after which the spatiotemporal and neuronal profiles of Npas4 protein expression were analysed by immunohistochemistry at different time points post-reperfusion. Focal cerebral ischemia induced an early, transient and robust upregulation of Npas4 in a brain region-dependent manner involving predominantly principal neurons. Interestingly, we observed a unique differential induction of Npas4 protein expression in corticolimbic regions of the rat brain that are critically linked to cognition and emotion. These findings suggest that stroke-induced Npas4 upregulation may be involved in a transcriptional regulatory program within the corticolimbic circuitry following an ischemic insult.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Corteza Cerebral/metabolismo , Infarto de la Arteria Cerebral Media/metabolismo , Sistema Límbico/metabolismo , Regulación hacia Arriba , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Corteza Cerebral/patología , Sistema Límbico/patología , Masculino , Neuronas/metabolismo , Ratas , Ratas Sprague-Dawley
20.
Thorax ; 68(5): 485-6, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22993168

RESUMEN

RATIONALE: Smoking cessation interventions in outpatient settings have been demonstrated to be cost effective. Given this evidence, we aimed to evaluate the effectiveness of varenicline tartrate plus Quitline-counselling compared with Quitline-counselling alone when initiated in the inpatient setting. METHODS: Adult patients (18-75 years) admitted with a smoking-related illness to three hospitals, were randomised to receive either 12-weeks of varenicline tartrate plus Quitline-counselling, (n=196) or Quitline-counselling alone, (n=196), with 12-months follow-up. RESULTS: For the primary analysis population (intention-to-treat), the proportion of subjects who remained continuously abstinent were significantly greater in the varenicline plus counselling arm (31.1%, n=61) compared with counselling alone (21.4%, n=42; RR 1.45, 95% CI 1.03 to 2.03, p=0.03). CONCLUSIONS: The combined use of varenicline plus counselling when initiated in the inpatient setting has produced a sustained smoking cessation benefit at 12-months follow-up, indicating a successful opportunistic treatment for smokers admitted with smoking related illnesses. TRIAL REGISTRATION: http://www.clinicaltrials.gov/ ClinicalTrials.gov identification number: NCT01141855.


Asunto(s)
Benzazepinas/farmacología , Consejo/métodos , Pacientes Internos , Quinoxalinas/farmacología , Cese del Hábito de Fumar/métodos , Fumar/efectos adversos , Adolescente , Adulto , Anciano , Australia/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Agonistas Nicotínicos/farmacología , Fumar/epidemiología , Factores de Tiempo , Resultado del Tratamiento , Vareniclina , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA