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1.
J Neurosci ; 42(19): 3931-3948, 2022 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-35379703

RESUMEN

The formation of connections within the mammalian neocortex is highly regulated by both extracellular guidance mechanisms and intrinsic gene expression programs. There are two types of cortical projection neurons (CPNs): those that project locally and interhemispherically and those that project to subcerebral structures such as the thalamus, hindbrain, and spinal cord. The regulation of cortical projection morphologies is not yet fully understood at the molecular level. Here, we report a role for Mllt11 (Myeloid/lymphoid or mixed-lineage leukemia; translocated to chromosome 11/All1 Fused Gene From Chromosome 1q) in the migration and neurite outgrowth of callosal projection neurons during mouse brain formation. We show that Mllt11 expression is exclusive to developing neurons and is enriched in the developing cortical plate (CP) during the formation of the superficial cortical layers. In cultured primary cortical neurons, Mllt11 is detected in varicosities and growth cones as well as the soma. Using conditional loss-of-function and gain-of-function analysis we show that Mllt11 is required for neuritogenesis and proper migration of upper layer CPNs. Loss of Mllt11 in the superficial cortex of male and female neonates leads to a severe reduction in fibers crossing the corpus callosum (CC), a progressive loss in the maintenance of upper layer projection neuron gene expression, and reduced complexity of dendritic arborization. Proteomic analysis revealed that Mllt11 associates with stabilized microtubules, and Mllt11 loss affected microtubule staining in callosal axons. Taken together, our findings support a role for Mllt11 in promoting the formation of mature upper-layer neuron morphologies and connectivity in the cerebral cortex.SIGNIFICANCE STATEMENT The regulation of cortical projection neuron (CPN) morphologies is an area of active investigation since the time of Cajal. Yet the molecular mechanisms of how the complex dendritic and axonal morphologies of projection neurons are formed remains incompletely understood. Although conditional mutagenesis analysis in the mouse, coupled with overexpression assays in the developing fetal brain, we show that a novel protein called Mllt11 is sufficient and necessary to regulate the dendritic and axonal characteristics of callosal projection neurons in the developing mammalian neocortex. Furthermore, we show that Mllt11 interacts with microtubules, likely accounting for its role in neuritogenesis.


Asunto(s)
Corteza Cerebral , Neocórtex , Proyección Neuronal , Proteínas Proto-Oncogénicas , Animales , Axones/fisiología , Corteza Cerebral/citología , Corteza Cerebral/fisiología , Cuerpo Calloso/fisiología , Femenino , Masculino , Ratones , Neocórtex/metabolismo , Vías Nerviosas/fisiología , Neuronas/fisiología , Proteómica , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/fisiología
2.
BMC Public Health ; 23(1): 1286, 2023 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-37403027

RESUMEN

BACKGROUND: The purpose of this community-based study was to create and advance knowledge on the social impacts of COVID-19 on mental health of Two-Spirit, gay, bisexual, and queer (2SGBQ+) cisgender and transgender men in Manitoba, Canada. METHODS: Participants (n = 20) from 2SGBQ + men's communities were recruited across Manitoba using printed flyers and social media. Individual interviews explored questions relating to the impacts of the COVID-19 pandemic on mental health, social isolation, and service access. Data were critically examined using thematic analysis and the social theory of biopolitics. RESULTS: Key themes focused on COVID-19 pandemic's negative impacts on 2SGBQ + men's mental health, loss of safe queer public spaces, and exacerbated inequities. During the COVID-19 pandemic in Manitoba, 2SGBQ + men experienced a profound loss of social connections, community spaces, and social networks which are specific to their socio-sexual identities, thereby intensifying pre-existing mental health disparities. These findings show how COVID-19 restrictions have come to reinforce the value of close personal communities, families of choice, and social networks among 2SGBQ + men in Manitoba, Canada. CONCLUSIONS: This study supports the line of research on minority stress, biosociality, and place by highlighting some potential links between 2SGBQ + men's mental health and their social and physical environments. This research points to important role of safe community spaces, events, and community organizations that support 2SGBQ + men's mental health.


Asunto(s)
COVID-19 , Minorías Sexuales y de Género , Masculino , Humanos , Salud Mental , Manitoba/epidemiología , Pandemias , COVID-19/epidemiología , Canadá/epidemiología
3.
J Integr Neurosci ; 22(2): 50, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36992597

RESUMEN

BACKGROUND: An estimated 99 in 100,000 people experience a traumatic brain injury (TBI), with 85% being mild (mTBI) in nature. The Post-Concussion Symptom Scale (PCSS), is a reliable and valid measure of post-mTBI symptoms; however, diagnostic specificity is challenging due to high symptom rates in the general population. Understanding the neurobiological characteristics that distinguish high and low PCSS raters may provide further clarification on this phenomenon. AIM: To explore the neurobiological characteristics of post-concussion symptoms through the association between PCSS scores, brain network connectivity (using quantitative electroencephalography; qEEG) and cognition in undergraduates. HYPOTHESES: high PCSS scorers will have (1) more network dysregulation and (2) more cognitive dysfunction compared to the low PCSS scorers. METHODS: A sample of 40 undergraduates were divided into high and low PCSS scorers. Brain connectivity was measured using qEEG, and cognition was measured via neuropsychological measures of sustained attention, inhibition, immediate attention, working memory, processing speed and inhibition/switching. RESULTS: Contrary to expectations, greater frontoparietal network dysregulation was seen in the low PCSS score group (p = 0.003). No significant difference in cognitive dysfunction was detected between high and low PCSS scorers. Post-hoc analysis in participants who had experienced mTBI revealed greater network dysregulation in those reporting a more recent mTBI. CONCLUSIONS: Measuring post-concussion symptoms alone is not necessarily informative about changes in underlying neural mechanisms. In an exploratory subset analysis, brain network dysregulation appears to be greater in the early post-injury phase compared to later. Further analysis of underlying PCSS constructs and how to measure these in a non-athlete population and clinical samples is warranted.


Asunto(s)
Conmoción Encefálica , Síndrome Posconmocional , Humanos , Síndrome Posconmocional/diagnóstico , Síndrome Posconmocional/psicología , Conmoción Encefálica/complicaciones , Conmoción Encefálica/diagnóstico , Conmoción Encefálica/psicología , Pruebas Neuropsicológicas , Australia , Encéfalo/diagnóstico por imagen , Cognición
4.
Rheumatology (Oxford) ; 61(2): 591-596, 2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33769451

RESUMEN

OBJECTIVES: B cell depletion therapy based on rituximab in patients with RA was pioneered at University College London Hospitals/University College London in 1998. The objective of this study was to evaluate long-term persistence of rituximab and identify factors associated with discontinuation of treatment. METHODS: Retrospective review of medical records from all rituximab-treated RA patients followed up in a dedicated clinic (1998-2020). Data collected included gender, disease duration, previous DMARDs, autoantibody status, age and concomitant therapy at first cycle, length of follow-up, and number of cycles. Drug survival and factors associated with drug discontinuation were analysed using Kaplan-Meier survival curves, log-rank test and Cox regression analysis. RESULTS: A total of 404 patients were included. Median disease duration and age at time of first rituximab cycle were 10 and 57 years, respectively. Median total follow-up was 55 months and median number of cycles five. 93.1% of patients were seropositive. Overall, 31.2% of patients stopped rituximab, with the largest reason for discontinuing being primary inefficacy (42.1%). Comparison of Kaplan-Meier curves showed that rituximab drug survival was lower in seronegative patients and in patients who had previously failed at least one biologic DMARD (bDMARD). Cox regression analysis revealed that rituximab discontinuation was associated with a greater number of previous bDMARDs. CONCLUSION: Many patients with RA achieve good control of their disease with repeated cycles of rituximab treatment. The most common reasons for treatment discontinuation were either primary or secondary inefficacy. Patients who were seronegative and who had previously failed other bDMARDs were more at risk of drug discontinuation.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Rituximab/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antirreumáticos/uso terapéutico , Artritis Reumatoide/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia , Adulto Joven
5.
Rheumatology (Oxford) ; 60(1): 277-287, 2021 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-32734288

RESUMEN

OBJECTIVE: To determine whether a patient-initiated DMARD self-monitoring service for people on MTX is a cost-effective model of care for patients with RA or PsA. METHODS: An economic evaluation was undertaken alongside a randomized controlled trial involving 100 patients. Outcome measures were quality of life and ESR assessed at baseline and post-intervention. Costs were calculated for healthcare usage using a United Kingdom National Health Service economic perspective. Sensitivity analysis was performed to explore the impact of nurse-led telephone helplines. Uncertainty around the cost-effectiveness ratios was estimated by bootstrapping and analysing the cost-effectiveness planes. RESULTS: Fifty-two patients received the intervention and 48 usual care. The difference in mean cost per case indicated that the intervention was £263 more expensive (P < 0.001; 95% CI: £149.14, £375.86) when the helpline costs were accounted for and £94 cheaper (P = 0.08; 95% CI: -£199.26, £10.41) when these costs were absorbed by the usual service. There were, however, statistically significant savings for the patient (P = 0.02; 95% CI: -£28.98, £3.00). When costs and effectiveness measures of ESR and quality of life measured, using the Short Form-12v1, were combined this did not show the patient-initiated service to be cost-effective at a statistically significant level. CONCLUSION: This patient-initiated service led to reductions in primary and secondary healthcare services that translated into reduced costs, in comparison with usual care, but were not cost-effective. Further work is needed to establish how nurse-led telephone triage services are integrated into rheumatology services and the associated costs of setting up and delivering them. TRIAL REGISTRATION: ClinicalTrials.gov, http://clinicaltrials.gov, ISRCTN21613721.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis Psoriásica/tratamiento farmacológico , Artritis Reumatoide/tratamiento farmacológico , Análisis Costo-Beneficio , Monitoreo de Drogas/economía , Metotrexato/uso terapéutico , Costos de la Atención en Salud , Humanos , Programas Nacionales de Salud/economía , Evaluación de Resultado en la Atención de Salud , Pautas de la Práctica en Enfermería , Calidad de Vida , Incertidumbre , Reino Unido
6.
Int J Mol Sci ; 22(19)2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34638997

RESUMEN

One of the mechanisms by which PI3 kinase can regulate platelet function is through phosphorylation of downstream substrates, including glycogen synthase kinase-3 (GSK3)α and GSK3ß. Platelet activation results in the phosphorylation of an N-terminal serine residue in GSK3α (Ser21) and GSK3ß (Ser9), which competitively inhibits substrate phosphorylation. However, the role of phosphorylation of these paralogs is still largely unknown. Here, we employed GSK3α/ß phosphorylation-resistant mouse models to explore the role of this inhibitory phosphorylation in regulating platelet activation. Expression of phosphorylation-resistant GSK3α/ß reduced thrombin-mediated platelet aggregation, integrin αIIbß3 activation, and α-granule secretion, whereas platelet responses to the GPVI agonist collagen-related peptide (CRP-XL) were significantly enhanced. GSK3 single knock-in lines revealed that this divergence is due to differential roles of GSK3α and GSK3ß phosphorylation in regulating platelet function. Expression of phosphorylation-resistant GSK3α resulted in enhanced GPVI-mediated platelet activation, whereas expression of phosphorylation-resistant GSK3ß resulted in a reduction in PAR-mediated platelet activation and impaired in vitro thrombus formation under flow. Interestingly, the latter was normalised in double GSK3α/ß KI mice, indicating that GSK3α KI can compensate for the impairment in thrombosis caused by GSK3ß KI. In conclusion, our data indicate that GSK3α and GSK3ß have differential roles in regulating platelet function.


Asunto(s)
Plaquetas/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Glucógeno Sintasa Quinasa 3/metabolismo , Activación Plaquetaria/genética , Agregación Plaquetaria/genética , Transducción de Señal/genética , Trombosis/metabolismo , Animales , Donantes de Sangre , Células Cultivadas , Modelos Animales de Enfermedad , Técnicas de Sustitución del Gen , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3 beta/genética , Humanos , Integrinas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Trombina/metabolismo , Trombosis/genética
7.
Lung ; 198(5): 803-810, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32870374

RESUMEN

PURPOSE: Bronchoalveolar lavage and transbronchial biopsy can be a useful tool in the evaluation of interstitial lung disease (ILD), but patient selection for this procedure remains poorly defined. Determining clinical characteristics that help with patient selection for bronchoscopy may improve confidence of ILD classification while limiting potential adverse outcomes associated with surgical lung biopsy. The purpose of this study is to identify factors that were associated with change in multidisciplinary ILD diagnosis (MDD) before and after incorporation of BAL and TBBx data. METHODS: We conducted a retrospective cohort study of ILD patients at a single center who underwent bronchoscopy in the diagnostic workup of ILD. We performed sequential MDD both pre- and post-bronchoscopy to calculate the frequency of change in diagnosis after incorporating information from BAL and TBBx and identify features associated with change in diagnosis. RESULTS: 245 patients were included in the study. Bronchoscopy led to a change in diagnosis in 58 patients (23.7%). The addition of TBBx to BAL increased diagnostic yield from 21.8 to 34.1% (p = 0.027). Identification of antigen, HRCT scan inconsistent with UIP, and absence of a pre-bronchoscopy diagnosis of CTD-ILD or IPAF were associated with a change in diagnosis after bronchoscopy. CONCLUSION: Our study suggests clinical features that may assist with patient selection for bronchoscopy. We suggest bronchoscopy in patients with identified antigen or an HRCT that is consistent with a non-IPF diagnosis. Appropriate patient selection for bronchoscopy may improve ILD diagnostic confidence and avoid potential complications from more invasive and higher risk procedures.


Asunto(s)
Alveolitis Alérgica Extrínseca/diagnóstico , Biopsia , Lavado Broncoalveolar , Broncoscopía , Enfermedades Pulmonares Intersticiales , Pulmón , Biopsia/efectos adversos , Biopsia/métodos , Biopsia/estadística & datos numéricos , Lavado Broncoalveolar/métodos , Lavado Broncoalveolar/estadística & datos numéricos , Broncoscopía/métodos , Broncoscopía/estadística & datos numéricos , Diagnóstico Diferencial , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Enfermedades Pulmonares Intersticiales/diagnóstico , Enfermedades Pulmonares Intersticiales/epidemiología , Masculino , Persona de Mediana Edad , Evaluación de Procesos y Resultados en Atención de Salud , Selección de Paciente , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Estados Unidos/epidemiología
8.
J Biol Chem ; 292(5): 1691-1704, 2017 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-27903653

RESUMEN

The class I PI3K family of lipid kinases plays an important role in integrin αIIbß3 function, thereby supporting thrombus growth and consolidation. Here, we identify Ras/Rap1GAP Rasa3 (GAP1IP4BP) as a major phosphatidylinositol 3,4,5-trisphosphate-binding protein in human platelets and a key regulator of integrin αIIbß3 outside-in signaling. We demonstrate that cytosolic Rasa3 translocates to the plasma membrane in a PI3K-dependent manner upon activation of human platelets. Expression of wild-type Rasa3 in integrin αIIbß3-expressing CHO cells blocked Rap1 activity and integrin αIIbß3-mediated spreading on fibrinogen. In contrast, Rap1GAP-deficient (P489V) and Ras/Rap1GAP-deficient (R371Q) Rasa3 had no effect. We furthermore show that two Rasa3 mutants (H794L and G125V), which are expressed in different mouse models of thrombocytopenia, lack both Ras and Rap1GAP activity and do not affect integrin αIIbß3-mediated spreading of CHO cells on fibrinogen. Platelets from thrombocytopenic mice expressing GAP-deficient Rasa3 (H794L) show increased spreading on fibrinogen, which in contrast to wild-type platelets is insensitive to PI3K inhibitors. Together, these results support an important role for Rasa3 in PI3K-dependent integrin αIIbß3-mediated outside-in signaling and cell spreading.


Asunto(s)
Proteínas Activadoras de GTPasa/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Transducción de Señal/fisiología , Sustitución de Aminoácidos/genética , Animales , Plaquetas/metabolismo , Plaquetas/patología , Células CHO , Cricetinae , Cricetulus , Modelos Animales de Enfermedad , Proteínas Activadoras de GTPasa/genética , Humanos , Ratones , Ratones Mutantes , Mutación Missense , Fosfatidilinositol 3-Quinasas/genética , Fosfatos de Fosfatidilinositol/genética , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/genética , Receptores Citoplasmáticos y Nucleares/genética , Trombocitopenia/genética , Trombocitopenia/metabolismo , Trombocitopenia/patología
9.
Ann Surg ; 265(1): 20-29, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27280501

RESUMEN

OBJECTIVE: To examine our pilot to transplant selected patients with acute alcoholic hepatitis, initiated in October 2012. BACKGROUND: Six months of alcohol abstinence is typically required before liver transplant. A Franco-Belgian protocol showed that early transplant in severe alcoholic hepatitis could improve survival with low incidence of alcohol relapse. Application of this controversial indication is growing despite unclear generalizability. METHODS: Data was collected on all patients with alcohol-related liver disease since initiation of the pilot through June 2015. Patients were stratified into two groups: severe alcoholic hepatitis as first liver decompensation (Group 1), alcoholic cirrhosis with ≥6 months abstinence (Group 2). Alcohol relapse was defined as any evidence of alcohol consumption after transplant, which was assessed for harmful patterns of binge or frequent drinking. RESULTS: Forty-three patients underwent liver transplant, including 17 patients in Group 1. Six-month survival was 100% versus 89% for Groups 1 and 2, respectively (P = 0.27). Alcohol relapse was similar in Group 1 versus Group 2: 23.5% versus 29.2% (P > 0.99). Harmful drinking was higher in Group 1 versus Group 2, despite lack of statistical significance: 23.5% versus 11.5% (P = 0.42). CONCLUSIONS: In this pilot with carefully selected patients, early liver transplant provided excellent short-term survival, and similar rates of alcohol relapse compared with patients with 6 months of abstinence. Harmful patterns of relapse remain challenging in this population, highlighting the need for validated models to predict alcohol relapse, and need for extreme caution in selecting patients for this exceptional indication. Larger prospective studies and longer follow up are necessary.


Asunto(s)
Abstinencia de Alcohol/estadística & datos numéricos , Trastornos Relacionados con Alcohol/prevención & control , Hepatitis Alcohólica/cirugía , Trasplante de Hígado , Prevención Secundaria , Adulto , Anciano , Trastornos Relacionados con Alcohol/complicaciones , Femenino , Estudios de Seguimiento , Hepatitis Alcohólica/mortalidad , Hepatitis Alcohólica/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Recurrencia , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento
10.
P T ; 42(12): 735-738, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29234211

RESUMEN

Bezlotoxumab (Zinplava) to prevent the recurrence of Clostridium difficile infection.

11.
Ann Rheum Dis ; 75(7): 1343-9, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26290587

RESUMEN

OBJECTIVE: To determine the effectiveness of a patient-initiated disease-modifying antirheumatic drugs (DMARD) self-monitoring service for people with rheumatoid (RA) or psoriatic arthritis (PsA) on methotrexate. METHODS: A two-arm, single-centre, randomised controlled trial assessing superiority in relation to healthcare use, clinical and psychosocial outcomes. Participants were 100 adults with either RA or PsA on a stable dose of methotrexate, randomly assigned to usual care or the patient-initiated service. Intervention participants were trained how to understand and interpret their blood tests and use this information to initiate care from their clinical nurse specialist (CNS). The primary outcome was the number of outpatient visits to the CNS during the trial period. Differences between groups were analysed using Poisson regression models. Secondary outcomes were collected at baseline and after the third and sixth blood tests. Disease activity was measured using either the Disease Activity Score in 28 joints or Psoriatic Arthritis Response Criteria (PsARC), pain and fatigue using a visual numeric scale and the Health Assessment Question-II, Hospital Anxiety and Depression Scale and SF12 were completed to assess disability, mood and quality of life, respectively. Differences between groups over time on secondary outcomes were analysed using multilevel models. RESULTS: The patient-initiated DMARD self-monitoring service was associated with 54.55% fewer visits to the CNS (p<0.0001), 6.80% fewer visits to the rheumatologist (p=0.23) and 38.80% fewer visits to the general practitioner (p=0.07), compared with control participants. There was no association between trial arm and any of the clinical or psychosocial outcomes. CONCLUSIONS: The results suggest that a patient-initiated service that incorporates patients' self-monitoring DMARD therapy can lead to significant reductions in healthcare use, while maintaining clinical and psychosocial well-being. TRIAL REGISTRATION NUMBER: ISRCTN21613721.


Asunto(s)
Antirreumáticos/administración & dosificación , Artritis Psoriásica/tratamiento farmacológico , Artritis Reumatoide/tratamiento farmacológico , Monitoreo Ambulatorio/métodos , Autocuidado/métodos , Atención Ambulatoria/estadística & datos numéricos , Artritis Psoriásica/sangre , Artritis Reumatoide/sangre , Quimioterapia Combinada , Femenino , Humanos , Masculino , Metotrexato/administración & dosificación , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
12.
Blood ; 121(7): 1209-19, 2013 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-23243278

RESUMEN

Patients with myeloproliferative disorders (MPDs), such as essential thrombocythemia (ET) have increased risk of thrombosis and bleeding, which are major sources of morbidity and mortality. Most MPD patients have a gain of function mutation in Janus kinase 2 (JAK2V617F), but little is known how JAK2V617F affects platelet function. Here, we demonstrate that platelets from ET patients have impaired SFLLRN-mediated fibrinogen binding and have lost the potentiating effect of thrombopoietin (which couples to JAK2) on this pathway. In contrast, SFLLRN-mediated P-selectin expression, ATP secretion, phosphorylation of the PKC substrate pleckstrin, and Ca(2+) mobilization were unaffected in JAK2V617F positive platelets. In addition, thrombopoietin-mediated JAK2 phosphorylation was unchanged, suggesting that signaling pathways activated downstream of JAK2 are impaired. Indeed, we found that platelets from JAK2V617F positive ET patients have significantly reduced phosphorylation of the PI3 kinase substrate Akt, and have reduced activation of Rap1 in response to thrombopoietin, IGF-1,ADP, SFLLRN, and thrombin. This effect was independent of Giα P2Y12 purinergic receptor function as ADP-mediated inhibition of VASP phosphorylation was unchanged. These results demonstrate that the PI3 kinase/Rap1 pathway is intrinsically impaired in platelets from JAK2V617F-positive ET patients, resulting in diminished thrombin and thrombopoietin-mediated integrin α(IIb)ß(3) activation.


Asunto(s)
Plaquetas/fisiología , Fosfatidilinositol 3-Quinasas/sangre , Activación Plaquetaria/fisiología , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Proteínas de Unión a Telómeros/sangre , Trombocitemia Esencial/sangre , Adulto , Anciano , Sustitución de Aminoácidos , Plaquetas/efectos de los fármacos , Estudios de Casos y Controles , Femenino , Fibrinógeno/metabolismo , Humanos , Janus Quinasa 2/antagonistas & inhibidores , Janus Quinasa 2/sangre , Janus Quinasa 2/genética , Masculino , Persona de Mediana Edad , Mutación Missense , Fragmentos de Péptidos/farmacología , Fosforilación , Activación Plaquetaria/efectos de los fármacos , Activación Plaquetaria/genética , Complejo Shelterina , Transducción de Señal/efectos de los fármacos , Trombina/farmacología , Trombocitemia Esencial/genética , Trombopoyetina/farmacología
13.
Arterioscler Thromb Vasc Biol ; 34(8): 1681-8, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24903091

RESUMEN

OBJECTIVE: Platelet hyperactivity is a contributing factor in the pathogenesis of cardiovascular disease and can be induced by elevated levels of circulating growth factors, such as insulin-like growth factor-1 (IGF-1). IGF-1 is a primer that cannot stimulate platelet activation by itself, but in combination with physiological stimuli can potentiate platelet functional responses via a phosphoinositide 3-kinase-dependent mechanism. In this study, we explored the role of the phosphoinositide 3-kinase p110α isoform in IGF-1-mediated enhancement of platelet function. APPROACH AND RESULTS: Using a platelet-specific p110α knockout murine model, we demonstrate that genetic deletion, similar to pharmacological inactivation of p110α, did not affect proteinase-activated receptor 4 signaling to Akt/protein kinase B but significantly reduced IGF-1-mediated Akt phosphorylation. The p110ß inhibitor TGX-221 abolished IGF-1-induced Akt phosphorylation in p110α-deficient platelets, demonstrating that both p110α and p110ß contribute to IGF-1-mediated Akt phosphorylation. Genetic deletion of p110α had no effect on IGF-1-mediated increases in thrombus formation on collagen and enhancement of proteinase-activated receptor 4-mediated integrin activation and α-granule secretion. In contrast, pharmacological inhibition of p110α blocked IGF-1-mediated potentiation of integrin activation and α-granule secretion. Functional enhancement by IGF-1 in p110α knockout samples was lost after TGX-221 treatment, suggesting that p110ß drives priming in the absence of the p110α isoform. CONCLUSIONS: Together, these results demonstrate that both p110α and p110ß are involved in Akt signaling by IGF-1, but that it is the p110α isoform that is responsible for IGF-1-mediated potentiation of platelet function.


Asunto(s)
Plaquetas/enzimología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Activación Plaquetaria , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Plaquetas/efectos de los fármacos , Fosfatidilinositol 3-Quinasa Clase I , Integrina alfa2/metabolismo , Integrina beta3/metabolismo , Ratones , Ratones Noqueados , Fosfatidilinositol 3-Quinasas/deficiencia , Fosfatidilinositol 3-Quinasas/genética , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosforilación , Activación Plaquetaria/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Receptores de Trombina/metabolismo , Vesículas Secretoras/metabolismo , Transducción de Señal , Trombosis/sangre , Trombosis/enzimología , Factores de Tiempo
15.
Ann Emerg Med ; 66(1): 51-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24997562

RESUMEN

Emergency department (ED) information systems are designed to support efficient and safe emergency care. These same systems often play a critical role in disasters to facilitate real-time situation awareness, information management, and communication. In this article, we describe one ED's experiences with ED information systems during the April 2013 Boston Marathon bombings. During postevent debriefings, staff shared that our ED information systems and workflow did not optimally support this incident; we found challenges with our unidentified patient naming convention, real-time situational awareness of patient location, and documentation of assessments, orders, and procedures. As a result, before our next mass gathering event, we changed our unidentified patient naming convention to more clearly distinguish multiple, simultaneous, unidentified patients. We also made changes to the disaster registration workflow and enhanced roles and responsibilities for updating electronic systems. Health systems should conduct disaster drills using their ED information systems to identify inefficiencies before an actual incident. ED information systems may require enhancements to better support disasters. Newer technologies, such as radiofrequency identification, could further improve disaster information management and communication but require careful evaluation and implementation into daily ED workflow.


Asunto(s)
Bombas (Dispositivos Explosivos) , Servicio de Urgencia en Hospital , Sistemas de Información en Hospital , Incidentes con Víctimas en Masa , Terrorismo , Boston , Registros Electrónicos de Salud , Servicio de Urgencia en Hospital/organización & administración , Sistemas de Información en Hospital/organización & administración , Humanos , Sistemas de Identificación de Pacientes
16.
Behav Res Methods ; 47(1): 228-34, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24719265

RESUMEN

Existing sets of social and emotional stimuli suitable for social cognition research are limited in many ways, including size, unimodal stimulus delivery, and restriction to major universal emotions. Existing measures of social cognition could be improved by taking advantage of item response theory and adaptive testing technology to develop instruments that obtain more efficient measures of multimodal social cognition. However, for this to be possible, large pools of emotional stimuli must be obtained and validated. We present the development of a large, high-quality multimedia stimulus set produced by professional adult and child actors (ages 5 to 74) containing both visual and vocal emotional expressions. We obtained over 74,000 audiovisual recordings of a wide array of emotional and social behaviors, including the main universal emotions (happiness, sadness, anger, fear, disgust, and surprise), as well as more complex social expressions (pride, affection, sarcasm, jealousy, and shame). The actors generated a high quantity of technically superior, ecologically valid stimuli that were digitized, archived, and rated for accuracy and intensity of expressions. A subset of these facial and vocal expressions of emotion and social behavior were submitted for quantitative ratings to generate parameters for validity and discriminability. These stimuli are suitable for affective neuroscience-based psychometric tests, functional neuroimaging, and social cognitive rehabilitation programs. The purposes of this report are to describe the method of obtaining and validating this database and to make it accessible to the scientific community. We invite all those interested in participating in the use and validation of these stimuli to access them at www.med.upenn.edu/bbl/actors/index.shtml .


Asunto(s)
Cognición , Emoción Expresada , Conducta Social , Adulto , Anciano , Recursos Audiovisuales/normas , Investigación Conductal/métodos , Niño , Bases de Datos Factuales , Humanos , Pruebas Neuropsicológicas/normas , Psicometría/instrumentación , Psicometría/métodos , Reproducibilidad de los Resultados
17.
J Biol Chem ; 288(6): 3918-28, 2013 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-23239877

RESUMEN

Glycogen synthase kinase-3 is a Ser/Thr kinase, tonically active in resting cells but inhibited by phosphorylation of an N-terminal Ser residue (Ser(21) in GSK3α and Ser(9) in GSK3ß) in response to varied external stimuli. Recent work suggests that GSK3 functions as a negative regulator of platelet function, but how GSK3 is regulated in platelets has not been examined in detail. Here, we show that early thrombin-mediated GSK3 phosphorylation (0-30 s) was blocked by PKC inhibitors and largely absent in platelets from PKCα knock-out mice. In contrast, late (2-5 min) GSK3 phosphorylation was dependent on the PI3K/Akt pathway. Similarly, early thrombin-mediated inhibition of GSK3 activity was blocked in PKCα knock-out platelets, whereas the Akt inhibitor MK2206 reduced late thrombin-mediated GSK3 inhibition and largely prevented GSK3 inhibition in PKCα knock-out platelets. More importantly, GSK3 phosphorylation contributes to platelet function as knock-in mice where GSK3α Ser(21) and GSK3ß Ser(9) were mutated to Ala showed a significant reduction in PAR4-mediated platelet aggregation, fibrinogen binding, and P-selectin expression, whereas the GSK3 inhibitor CHIR99021 enhanced these responses. Together, these results demonstrate that PKCα and Akt modulate platelet function by phosphorylating and inhibiting GSK3α/ß, thereby relieving the negative effect of GSK3α/ß on thrombin-mediated platelet activation.


Asunto(s)
Plaquetas/metabolismo , Glucógeno Sintasa Quinasa 3/metabolismo , Agregación Plaquetaria/fisiología , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Proteína Quinasa C-alfa/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Vesículas Secretoras/metabolismo , Trombina/metabolismo , Sustitución de Aminoácidos , Animales , Fibrinógeno/metabolismo , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3 beta , Compuestos Heterocíclicos con 3 Anillos/farmacología , Ratones , Ratones Noqueados , Mutación Missense , Selectina-P/biosíntesis , Fosforilación/efectos de los fármacos , Fosforilación/fisiología , Agregación Plaquetaria/efectos de los fármacos , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/genética , Proteína Quinasa C-alfa/genética , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/genética , Piridinas/farmacología , Pirimidinas/farmacología , Vesículas Secretoras/genética , Trombina/farmacología
18.
Int J Drug Policy ; 129: 104503, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38905942

RESUMEN

BACKGROUND: Within Manitoba and Saskatchewan, pre-existing health inequities amongst Indigenous groups were intensified during the COVID-19 pandemic. Service disruptions in the health and social service sector-combined with the effects of intersectional stigma-disproportionately impacted Indigenous peoples living with HIV (IPLH). IPLH experience structural violence and necropolitical exclusion through systemic forms of stigma situated within Canada's expansive colonial history. Utilizing the theoretical foundations of structural violence and necropolitics, this qualitative study examines how the COVID-19 pandemic amplified preceding states of inequity for IPLH. METHODS: Semi-structured interviews were conducted with 60 participants. The sample comprised of those with lived experience (n = 45) as well as those who provided services for IPLH (n = 15). Indigenous Storywork guided the data collection and analysis process. Topics explored within each interview included access to health and social services, harm reduction, substance use, and experiences in providing services during COVID-19 pandemic. Thematic analysis was used to identify common themes throughout each story. RESULTS: Our results indicate that the COVID-19 pandemic exposed and amplified pre-existing forms of structural violence and necropolitical logics for IPLH within Manitoba and Saskatchewan. Specifically, we describe how structural violence and necropolitics are manifested via three main avenues- (i) restrictions and removal of care, (ii) bureaucracy and institutional care politics, and (iii) discrimination and systemic racism within the Canadian healthcare system. CONCLUSION: The COVID-19 pandemic within Manitoba and Saskatchewan sparked massive changes in service provision within settler-colonial and neoliberal institutions of care. For those services that remained open to IPLH, masking requirements, questionnaire requirements, scheduling requirements, and a lack of in-person services acted as only some of the barriers described by community members as detrimental to care access. Increased experiences of discrimination in health care on the basis of substance use or HIV status further limited access to needed services.

19.
Glob Public Health ; 18(1): 2184484, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36934431

RESUMEN

Financial technology tools have been utilised to create readily available mobile loan platforms for urban-based, daily-wage earners in Kenya. From a financial lending perspective, this development signals greater inclusion and equality in formal bank financing systems. In this paper, however, we examine mobile loans and their repayment from the perspective of women who sell sex in Nairobi, drawing upon the qualitative findings of two community-based studies conducted in close collaboration with sex worker-led organisations serving the sexual health needs of their peers. Our findings suggest that mobile loans may undermine the financial security strategies and economic independence of sex workers, leaving these women in more precarious economic circumstances, which have been shown in other instances to have effects on sexual risk taking and vulnerability to HIV infection.


Asunto(s)
Infecciones por VIH , Trabajadores Sexuales , Salud Sexual , Humanos , Femenino , Infecciones por VIH/prevención & control , Kenia , Conducta Sexual
20.
BMC Med Genomics ; 16(1): 284, 2023 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-37951941

RESUMEN

Deep vein thrombosis (DVT) is the formation of a blood clot in a deep vein. DVT can lead to a venous thromboembolism (VTE), the combined term for DVT and pulmonary embolism, a leading cause of death and disability worldwide. Despite the prevalence and associated morbidity of DVT, the underlying causes are not well understood. Our aim was to leverage publicly available genetic summary association statistics to identify causal risk factors for DVT. We conducted a Mendelian randomization phenome-wide association study (MR-PheWAS) using genetic summary association statistics for 973 exposures and DVT (6,767 cases and 330,392 controls in UK Biobank). There was evidence for a causal effect of 57 exposures on DVT risk, including previously reported risk factors (e.g. body mass index-BMI and height) and novel risk factors (e.g. hyperthyroidism and varicose veins). As the majority of identified risk factors were adiposity-related, we explored the molecular link with DVT by undertaking a two-sample MR mediation analysis of BMI-associated circulating proteins on DVT risk. Our results indicate that circulating neurogenic locus notch homolog protein 1 (NOTCH1), inhibin beta C chain (INHBC) and plasminogen activator inhibitor 1 (PAI-1) influence DVT risk, with PAI-1 mediating the BMI-DVT relationship. Using a phenome-wide approach, we provide putative causal evidence that hyperthyroidism, varicose veins and BMI enhance the risk of DVT. Furthermore, the circulating protein PAI-1 has a causal role in DVT aetiology and is involved in mediating the BMI-DVT relationship.


Asunto(s)
Hipertiroidismo , Várices , Trombosis de la Vena , Humanos , Inhibidor 1 de Activador Plasminogénico/genética , Factores de Riesgo , Trombosis de la Vena/genética
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