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1.
J Vasc Surg ; 2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38912995

RESUMEN

OBJECTIVE: Supervised exercise therapy (SET) provides clinical benefit for patients suffering from intermittent claudication and has been widely recommended as first-line therapy before endovascular or surgical intervention. However, published rates of SET program completion range from 5% to 55%, with historic completion of 54% at our own institution. As such, we sought to identify if targeted patient-supportive interventions improve SET completion rates while still maintaining efficacious SET programming. METHODS: Patients who were diagnosed with intermittent claudication, as defined by ankle-brachial index (ABI) <0.9 without rest pain, were offered enrollment in a prospective quality improvement protocol for our 12-week SET for peripheral artery disease program. Program completion was defined as ≥24 of 36 offered sessions over 12 weeks. A three-pronged approach was utilized to improve completion during the study, including financial incentives up to $180, scheduled coaching with our advanced practitioner staff, and informational materials on the importance of SET programming and lifestyle modification. Patient-reported improvements in walking symptoms were tracked via regularly administered questionnaires. Functional measures of SET programming including total walking duration and distance, metabolic equivalent of task, and ABIs; vascular intervention within 12-months after enrollment was also collected and compared using univariate paired analysis. RESULTS: In total, seventy-three patients were enrolled in SET for peripheral artery disease programming over the study period. Utilizing our three-pronged coaching approach, 56 patients completed SET programming, increasing our SET completion rate to 76.7% over a 2-year study period. Compared with pre-SET baseline, patients who completed SET noted less pain, aching, cramps in calves when walking (P = .004), and less difficulty walking 1 block (P = .038). Additionally, patients significantly increased their metabolic equivalent of task (3.1 vs 2.6; P < .001), total walking duration (30 mins vs 13.5 mins; P < .001), and total walking distance (0.7 vs 0.3 miles; P < .001) from their pre-SET baseline. There were no changes in participant ABIs from enrollment to completion in participants. Patients who completed SET programming also delayed vascular intervention compared with those who did not complete SET or declined participation (213.5 vs 122.5 days from enrollment; P = .041). CONCLUSIONS: Targeted incentives, including cost-coverage vouchers and personalized coaching with instructional materials, successfully improved patient completion of a prescribed SET program. Patients who completed SET programming reported subjective improvement in walking symptoms and objective walking benefits. In addition, these patients had delayed time to vascular intervention, supporting current vascular guidelines advocating for effective SET therapy prior to offering vascular intervention for intermittent claudication.

2.
Ann Vasc Surg ; 106: 124-131, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38810724

RESUMEN

BACKGROUND: Supervised exercise therapy (SET) provides clinical benefit for patients suffering from intermittent claudication due to peripheral artery disease (PAD). However, enrollment in programs when offered remains low. We sought to identify patient-reported barriers to enrollment in SET as part of a prospective quality improvement program. METHODS: Patients who presented to clinic and were diagnosed with claudication were offered enrollment in a prospective quality improvement protocol, offered at 9 regional offices throughout our health system. Both patients who enrolled and declined enrollment were offered a 12-question questionnaire to identify potential barriers to enrollment. Additional data including gender, smoking status, ankle-brachial index (ABI), proximity to the nearest regional office, and disadvantage levels of neighborhoods (low: 1-3, medium: 4-7, and high: 8-10 area deprivation index [ADI]) was collected and compared by program participation using univariate analysis. RESULTS: Patients enrolled in the SET program (n = 66 patients) versus those who declined (n = 84 patients) were of similar age (medium age: 71.4 vs. 69.7 years, P = 0.694), baseline ABI (0.6 vs. 0.6, P = 0.944), smoking status (former 56.1% vs. 53.6%, P = 0.668), distance away from outpatient center (8.2 mi vs. 8.4 mi, P = 0.249), and had similar Connecticut state ADIs (2021 high-disadvantage: 35.4% vs. 33.3%, P = 0.549). Patients participating in the SET program were more likely to be male (78.8% vs. 56.0%, P = 0.003). Top self-reported barriers for patients who declined participation included transportation/distance (39.3%), preference for independent walking (56.0%), inability to commit to 3 sessions per week (52.4%), and lack of interest (20.2%). In addition, a higher proportion of patients who declined participation identified severe barriers of preference for independent walking (39.3% vs. 1.5%, P < 0.001), inability to commit to 3 sessions per week (26.2% vs. 3.0% P < 0.001), transportation/distance issues (23.8% vs. 7.6% P = 0.008), and cost (27.4% vs. 9.1%, P = 0.005) as significant barriers for participation in SET. CONCLUSIONS: Patients who declined participation in SET for PAD had similar disease status and access to care than participating counterparts. Top reported barriers to enrollment include a preference for independent walking, transportation/distance, commitment to 3x/week program, and cost, which highlight areas of focus for equitable access to these limb-saving services.

3.
Epilepsy Behav ; 142: 109146, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37075509

RESUMEN

The purpose of our study was to explore how people with epilepsy fared during two of the most stringent 4-month society-wide COVID-19-related pandemic restrictions in Ireland, in 2020 and one year later in 2021. This was in the context of their seizure control, lifestyle factors, and access to epilepsy-related healthcare services. A 14-part questionnaire was administered to adults with epilepsy during virtual specialist epilepsy clinics in a University Hospital in Dublin, Ireland at the end of the two lockdowns. People with epilepsy were questioned on their epilepsy control, lifestyle factors, and quality of epilepsy-related medical care, compared to pre-COVID times. The study sample consisted of two separate cohorts of those diagnosed with epilepsy (100 (51.8%) in 2020, and 93 (48.2%) in 2021, with similar baseline characteristics. There was no significant change in seizure control or lifestyle factors from 2020 to 2021, except for deterioration in anti-seizure medication (ASM) adherence in 2021 compared to 2020 (p = 0.028). There was no correlation between ASM adherence and other lifestyle factors. Over the two years, poor seizure control was significantly associated with poor sleep (p < 0.001) and average seizure frequency in a month (p = 0.007). We concluded that there was no significant difference between seizure control or lifestyle factors between the two most stringent lockdowns in Ireland, in 2020 and 2021. Furthermore, people with epilepsy reported that throughout the lockdowns access to services was well maintained, and they felt well supported by their services. Contrary to the popular opinion that COVID lockdowns greatly affected patients with chronic diseases, we found that those with epilepsy attending our service remained largely stable, optimistic, and healthy during this time.


Asunto(s)
COVID-19 , Epilepsia , Adulto , Humanos , COVID-19/epidemiología , Pandemias , Control de Enfermedades Transmisibles , Epilepsia/complicaciones , Epilepsia/epidemiología , Epilepsia/terapia , Encuestas y Cuestionarios
4.
Metab Brain Dis ; 38(7): 2383-2391, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37341855

RESUMEN

Multiple sclerosis (MS) is the most common causes of non-traumatic disability in young adults worldwide. MS pathophysiologies include the formation of inflammatory lesions, axonal damage and demyelination, and blood brain barrier (BBB) disruption. Coagulation proteins, including factor (F)XII, can serve as important mediators of the adaptive immune response during neuroinflammation. Indeed, plasma FXII levels are increased during relapse in relapsing-remitting MS patients, and previous studies showed that reducing FXII levels was protective in a murine model of MS, experimental autoimmune encephalomyelitis (EAE). Our objective was to determine if pharmacological targeting of FXI, a major substrate of activated FXII (FXIIa), improves neurological function and attenuates CNS damage in the setting of EAE. EAE was induced in male mice using murine myelin oligodendrocyte glycoprotein peptides combined with heat-inactivated Mycobacterium tuberculosis and pertussis toxin. Upon onset of symptoms, mice were treated every other day intravenously with anti-FXI antibody, 14E11, or saline. Disease scores were recorded daily until euthanasia for ex vivo analyses of inflammation. Compared to the vehicle control, 14E11 treatment reduced the clinical severity of EAE and total mononuclear cells, including CD11b+CD45high macrophage/microglia and CD4+ T cell numbers in brain. Following pharmacological targeting of FXI, BBB disruption was reduced, as measured by decreased axonal damage and fibrin(ogen) accumulation in the spinal cord. These data demonstrate that pharmacological inhibition of FXI reduces disease severity, immune cell migration, axonal damage, and BBB disruption in mice with EAE. Thus, therapeutic agents targeting FXI and FXII may provide a useful approach for treating autoimmune and neurologic disorders.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Animales , Masculino , Ratones , Encéfalo/metabolismo , Encefalomielitis Autoinmune Experimental/metabolismo , Factor XI/antagonistas & inhibidores , Factor XI/metabolismo , Ratones Endogámicos C57BL , Esclerosis Múltiple/patología , Glicoproteína Mielina-Oligodendrócito , Médula Espinal/metabolismo
5.
J Biol Chem ; 296: 100807, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34022222

RESUMEN

Insulin sensitizers and incretin mimetics are antidiabetic agents with vastly different mechanisms of action. Thiazolidinedione (TZD) insulin sensitizers are associated with weight gain, whereas glucagon-like peptide-1 receptor agonists can induce weight loss. We hypothesized that combination of a TZD insulin sensitizer and the glucagon-like peptide-1 receptor agonist liraglutide would more significantly improve mouse models of diabetes and nonalcoholic steatohepatitis (NASH). Diabetic db/db and MS-NASH mice were treated with the TZD MSDC-0602K by oral gavage, liraglutide (Lira) by s.c. injection, or combination 0602K+Lira. Lira slightly reduced body weight and modestly improved glycemia in db/db mice. Comparatively, 0602K-treated and 0602K+Lira-treated mice exhibited slight weight gain but completely corrected glycemia and improved glucose tolerance. 0602K reduced plasma insulin, whereas Lira further increased the hyperinsulinemia of db/db mice. Surprisingly, 0602K+Lira treatment reduced plasma insulin and C-peptide to the same extent as mice treated with 0602K alone. 0602K did not reduce glucose-stimulated insulin secretion in vivo, or in isolated islets, indicating the reduced insulinemia was likely compensatory to improved insulin sensitivity. In MS-NASH mice, both 0602K or Lira alone improved plasma alanine aminotransferase and aspartate aminotransferase, as well as liver histology, but more significant improvements were observed with 0602K+Lira treatment. 0602K or 0602K+Lira also increased pancreatic insulin content in both db/db and MS-NASH mice. In conclusion, MSDC-0602K corrected glycemia and reduced insulinemia when given alone, or in combination with Lira. However, 0602K+Lira combination more significantly improved glucose tolerance and liver histology, suggesting that this combination treatment may be an effective therapeutic strategy for diabetes and NASH.


Asunto(s)
Acetofenonas/uso terapéutico , Hipoglucemiantes/uso terapéutico , Insulina/metabolismo , Liraglutida/uso terapéutico , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Tiazolidinedionas/uso terapéutico , Animales , Quimioterapia Combinada , Femenino , Resistencia a la Insulina , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/metabolismo
6.
Ann Vasc Surg ; 87: 113-123, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35339593

RESUMEN

BACKGROUND: Sex-related discrepancies after standard endovascular aneurysm repair (EVAR) are noted to disproportionally affect females. A growing body of literature suggests similar disparities may extend to complex fenestrated or branched endovascular aneurysm repair (FBEVAR). However, recent examination of complex FBEVAR by a consortium of high-volume centers noted equivalent mortality among sexes. Whether similar results extend to non-trial data is unknown. METHODS: We examined all juxta-renal through type IV thoraco-abdominal aneurysms (sealing zones 6-8) which underwent elective FBEVAR within the Vascular Quality Initiative (VQI) database from January 2012 to December 2020. Urgent, symptomatic, ruptured, and staged cases were excluded, as were parallel stent grafts. Demographics, comorbid conditions, and technical factors were compared between sexes. Univariate analysis with Wilcoxon ranked sum tests and Chi-square tests of proportion were performed, followed by multivariate logistic regression for failure of target vessel technical success, reintervention, complications, and in-hospital mortality. RESULTS: Our analysis included 1,521 patients, 1,180 males (77.6%) and 341 females (22.4%). There were noted differences in pre-operative demographics, medical optimization, and technical aspects of the procedure. However, no difference was noted in proximal or distal sealing stents, number of fenestrations, or immediate endoleaks. On a multi variate logistic regression, female sex was an independent predictor of failure of target vessel technical success (odds ratio (OR) 3.339, 95% confidence interval (CI): 2.173-5.132, P < 0.001), reintervention (OR 2.192, 95% CI: 1.304-3.683, P = 0.003), complications (OR 1.747, 95% CI: 1.282-2.381, P < 0.001), and in-hospital mortality (OR 2.836, 95% CI: 1.510-5.328, P = 0.001). CONCLUSIONS: Females suffer worse outcomes after FBEVAR despite similar extent of disease, number of fenestrations, and incidence of immediate endoleak. Notable discrepancies were higher rates of chronic obstructive pulmonary disease (COPD) and lower rates of pre-operative aspirin, statin, and beta blocker therapy in females. Controlling for pre-operative demographics, female sex remained an independent predictor of worse outcomes. These discrepancies warrant further examination and should impact case planning for female patients undergoing complex aortic aneurysm repair.


Asunto(s)
Aneurisma de la Aorta Abdominal , Aneurisma de la Aorta Torácica , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Masculino , Humanos , Femenino , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/efectos adversos , Aneurisma de la Aorta Torácica/cirugía , Procedimientos Endovasculares/efectos adversos , Diseño de Prótesis , Resultado del Tratamiento , Factores de Tiempo , Endofuga/etiología , Endofuga/cirugía
7.
Aust J Rural Health ; 30(6): 760-771, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36448590

RESUMEN

OBJECTIVE: The objective of this study was to assess the clinical utility of a model of seven principles for effective visiting primary care services and to determine how it could be conceptualised as a tool for evaluation. SETTING: The research was undertaken in the context of visiting primary care services with an agency, Outback Futures, selected as a case study. PARTICIPANTS: Three executive staff with Outback Futures participated in the research. DESIGN: The case study design involved data collection by four group interviews conducted between July and November 2021. The interview data were analysed using thematic analysis. RESULTS: This case study is additional evidence for the clinical utility of the model of seven principles. The results reinforce the importance of a community-focussed approach to assess the impact of visiting service organisations on rural and remote communities. A comprehensive approach to evaluation is required to justify the investments made and safeguard the health and well-being of rural and remote residents. A self-assessment protocol has been established from the model for use by visiting services. Furthermore, three themes were drawn from the data: relationship is fundamental, the importance of co-design, and being effective as a visiting service is challenging. CONCLUSION: The model is appropriate for the case study organisation, and has clinical utility and implications for other visiting services. A self-assessment protocol has been developed. Future research should apply the model and protocol self-assessment tool in an effort to construct a consistent and credible approach to evaluation of visiting primary care services.


Asunto(s)
Accesibilidad a los Servicios de Salud , Servicios de Salud Rural , Humanos , Población Rural , Atención Primaria de Salud/métodos
8.
J Vasc Surg ; 74(3): 922-929, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33862188

RESUMEN

OBJECTIVE: Up to 14% of patients undergoing carotid endarterectomy with continuous electroencephalographic (EEG) neuromonitoring will require shunt placement because of EEG changes. However, the initial studies of transcarotid artery revascularization (TCAR) found only one patient with temporary EEG changes. We report our experience with intraoperative EEG monitoring during TCAR. METHODS: We conducted a retrospective review of patients who underwent TCAR at two urban hospitals within an integrated healthcare network from May 2017 to January 2020. The data included demographic information, patient comorbidities, symptom status, previous carotid interventions, anatomic details, contralateral disease, intraoperative vital signs and EEG changes, and postoperative major adverse events (transient ischemic attack, stroke, myocardial infarction [MI], and death) both initially and at 30 days postoperatively. The Fisher exact test was used for categorical data and the Wilcoxon rank sum test for continuous data. RESULTS: A total of 89 patients underwent TCAR during the study period, of whom 71 (79.8%) received intraoperative EEG neuromonitoring. Of the 89 patients, 70.8% were men and 29.2% were women. The median age was 75 years (IQR, 68-82.5 years). Symptomatic patients accounted for 41.6% of the cohort. Of the 71 patients who received continuous neuromonitoring, 9 experienced EEG changes during TCAR (12.7%). The changes resolved in seven patients with pressure augmentation in three and switching to a low flow toggle in three. One patient who had sustained EEG changes had a new postoperative neurologic deficit. The median carotid stenosis percentage on preoperative computed tomography angiography was lower for patients with EEG changes than for those without (67% vs 80%; P = .01). No correlation was found between symptom status or 30-day stroke in patients with and without EEG changes (P = .49 and P = .24, respectively). Overall, three postoperative strokes, two postoperative deaths, and one MI occurred, for a composite 30-day stroke, death, and MI rate of 6.7%. CONCLUSIONS: Changes in continuous EEG monitoring were more frequent in our study than previously reported. Less severe carotid stenosis might be associated with a greater incidence of EEG changes. Limited data are available on the prognostic ability of EEG to detect clinically relevant changes during TCAR, and further studies are warranted.


Asunto(s)
Estenosis Carotídea/cirugía , Electrocardiografía , Procedimientos Endovasculares , Monitorización Neurofisiológica Intraoperatoria , Anciano , Anciano de 80 o más Años , Estenosis Carotídea/diagnóstico , Estenosis Carotídea/mortalidad , Estenosis Carotídea/fisiopatología , Connecticut , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/mortalidad , Femenino , Humanos , Ataque Isquémico Transitorio/etiología , Masculino , Infarto del Miocardio/etiología , Valor Predictivo de las Pruebas , Sistema de Registros , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/etiología , Factores de Tiempo , Resultado del Tratamiento
9.
Epilepsy Behav ; 115: 107664, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33334718

RESUMEN

BACKGROUND: Coproduced epilepsy care sees people with epilepsy (PwE), their care-proxies, and healthcare providers (HCPs), working together as partners to build strong relationships, improve communication, trust, and share decision-making. Coproduction underpins good quality patient- and family-centered care (PFCC) that is responsive to individual patient needs, preferences, and values. By facilitating information sharing and exchange between partners, electronic patient portals (ePortal) can enable coproduction. This paper explores what HCPs, PwE, and their care-proxies value from their user experience of PiSCES, the Irish epilepsy ePortal. METHODS: A purposeful sample of actors involved in the receipt and delivery of epilepsy care and services were recruited via adult epilepsy centers at St James's and Beaumont Hospitals in Dublin. Interactive codesign sessions, surveys, and focus groups were used to elicit perspectives from PwE, care-proxies, and HCPs to understand their perception of how PiSCES could enhance or inhibit the epilepsy care process. RESULTS: Results illustrate that participants welcome the role PiSCES can play in: empowering PwE/care-proxies, strengthening confidence in the healthcare system; aiding memory; advancing health literacy, motivating PwE to understand their condition better; acting as a passport of care between different clinical settings; and creating a foundation for stronger coproduction partnerships. PiSCES was generally embraced; however, some HCPs expressed plausible concerns about how clinical implementation might impact their work practices. CONCLUSION: "Nothing about me without me" is a core value of the PiSCES initiative, recognizing that people need to be included in the planning of their own treatment and care. Our data show that PwE, their care-proxies, and HCPs value PiSCES potential, particularly in bolstering healthcare partnerships that foster inclusion, confidence, and trust.


Asunto(s)
Epilepsia , Portales del Paciente , Adulto , Epilepsia/terapia , Grupos Focales , Personal de Salud , Humanos , Investigación Cualitativa
10.
J Sci Food Agric ; 101(11): 4444-4455, 2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-33608900

RESUMEN

Marine algae are regarded as a promising nutrients resource in future as they can be sustainably cultured without land and high investment. These macroalgae are now widely processed into food and beverages, fertilizers and animal feed. Furthermore, bioactive compounds such as polysaccharides and polyphenols in seaweeds have proven to have antibacterial, antiviral and antifungal properties that can be utilized in cosmeceuticals, nutraceuticals and pharmaceuticals. As a key procedure in seaweed production, the postharvest process not only requires more laboured and energy but also affect the quality of the final product significantly. This article reviewed all current postharvest processes and technologies of seaweed and addressed potential postharvest strategies for seaweed production. © 2021 Society of Chemical Industry.


Asunto(s)
Extractos Vegetales/química , Algas Marinas/química , Animales , Cosmecéuticos/química , Suplementos Dietéticos/análisis , Manipulación de Alimentos , Humanos , Polifenoles/análisis , Polisacáridos/análisis
11.
Aust J Rural Health ; 29(5): 779-788, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34490938

RESUMEN

OBJECTIVE: Visiting health care services were developed to improve access to essential health care in rural and remote areas. Evaluating these services requires a robust framework. The objective of this study was to assess the confirmability and credibility of a model of 7 principles for effective visiting health care services. SETTING: Three iterative online survey rounds administered between July and December 2020. PARTICIPANTS: A heterogeneous panel of 13 experts in rural and remote health care participated, including managers of health care services, senior clinical staff in rural and remote regions and research academics specialising in rural infrastructure. DESIGN: The model was appraised using the Delphi method involving iterative online survey rounds to facilitate anonymous and structured discussion between panel members. RESULTS: Findings indicate consensus between panel members and support for a revised model. The revised model includes 4 modifications: (a) proposal of a new principle titled Feasibility, (b) restructure of 2 existing principles, (c) refined shape of the model to more accurately reflect the nature of service delivery and (d) detailed definitions of each principle. CONCLUSION: This study presents a credible, revised version of the model of 7 principles for effective visiting services. This will enhance the quality of the health workforce across geographically large countries, like Australia, enabling organisations to more effectively and consistently evaluate the impact of their service on rural and remote communities.


Asunto(s)
Servicios de Salud Rural , Australia , Atención a la Salud , Accesibilidad a los Servicios de Salud , Fuerza Laboral en Salud , Humanos , Población Rural
12.
J Sport Exerc Psychol ; 42(6): 433-442, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33207317

RESUMEN

Using a person-centered approach, the aim of this study was to examine how student-athletes' motives for multiple-goal pursuit relate to indices of well- and ill-being. Student-athletes (N = 362) from British universities identified the most important sporting and academic goals that they were pursuing over the academic year. The participants rated their extrinsic, introjected, identified, and intrinsic goal motives for each goal and completed measures of well- and ill-being. Latent profile analysis revealed six distinct profiles of goal motives, with variations in both the strength of motives and the motivational quality. Follow-up analyses revealed between-profile differences for well- and ill-being; students with more optimal goal motive profiles reported higher and lower well- and ill-being, respectively, than those with less optimal goal motives. To experience well-being benefits when pursuing multiple goals, student-athletes should strive for their academic and sporting goals with high autonomous and low controlled goal motives.

13.
Platelets ; 30(1): 126-135, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30560697

RESUMEN

Human platelets express two protease-activated receptors (PARs), PAR1 (F2R) and PAR4 (F2RL3), which are activated by a number of serine proteases that are generated during pathological events and cause platelet activation. Recent interest has focused on PAR4 as a therapeutic target, given PAR4 seems to promote experimental thrombosis and procoagulant microparticle formation, without a broadly apparent role in hemostasis. However, it is not yet known whether PAR4 activity plays a role in platelet-leukocyte interactions, which are thought to contribute to both thrombosis and acute or chronic thrombo-inflammatory processes. We sought to determine whether PAR4 activity contributes to granule secretion from activated platelets and platelet-leukocyte interactions. We performed in vitro and ex vivo studies of platelet granule release and platelet-leukocyte interactions in the presence of PAR4 agonists including PAR4 activating peptide, thrombin, cathepsin G, and plasmin in combination with small-molecule PAR4 antagonists. Activation of human platelets with thrombin, cathepsin G, or plasmin potentiated platelet dense granule secretion that was specifically impaired by PAR4 inhibitors. Platelet-leukocyte interactions and platelet P-selectin exposure the following stimulation with PAR4 agonists were also impaired by activated PAR4 inhibition in either a purified system or in whole blood. These results indicate PAR4-specific promotion of platelet granule release and platelet-leukocyte aggregate formation and suggest that pharmacological control of PAR4 activity could potentially attenuate platelet granule release or platelet-leukocyte interaction-mediated pathological processes.


Asunto(s)
Plaquetas/metabolismo , Comunicación Celular , Gránulos Citoplasmáticos/metabolismo , Leucocitos/metabolismo , Receptores de Trombina/metabolismo , Animales , Biomarcadores , Citometría de Flujo , Humanos , Masculino , Papio , Activación Plaquetaria , Agregación Plaquetaria
14.
J Biol Chem ; 292(21): 8616-8629, 2017 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-28408624

RESUMEN

Activated protein C (APC) is a multifunctional serine protease with anticoagulant, cytoprotective, and anti-inflammatory activities. In addition to the cytoprotective effects of APC on endothelial cells, podocytes, and neurons, APC cleaves and detoxifies extracellular histones, a major component of neutrophil extracellular traps (NETs). NETs promote pathogen clearance but also can lead to thrombosis; the pathways that negatively regulate NETosis are largely unknown. Thus, we studied whether APC is capable of directly inhibiting NETosis via receptor-mediated cell signaling mechanisms. Here, by quantifying extracellular DNA or myeloperoxidase, we demonstrate that APC binds human leukocytes and prevents activated platelet supernatant or phorbol 12-myristate 13-acetate (PMA) from inducing NETosis. Of note, APC proteolytic activity was required for inhibiting NETosis. Moreover, antibodies against the neutrophil receptors endothelial protein C receptor (EPCR), protease-activated receptor 3 (PAR3), and macrophage-1 antigen (Mac-1) blocked APC inhibition of NETosis. Select mutations in the Gla and protease domains of recombinant APC caused a loss of NETosis. Interestingly, pretreatment of neutrophils with APC prior to induction of NETosis inhibited platelet adhesion to NETs. Lastly, in a nonhuman primate model of Escherichia coli-induced sepsis, pretreatment of animals with APC abrogated release of myeloperoxidase from neutrophils, a marker of neutrophil activation. These findings suggest that the anti-inflammatory function of APC at therapeutic concentrations may include the inhibition of NETosis in an EPCR-, PAR3-, and Mac-1-dependent manner, providing additional mechanistic insight into the diverse functions of neutrophils and APC in disease states including sepsis.


Asunto(s)
Trampas Extracelulares/inmunología , Activación Neutrófila/inmunología , Neutrófilos/inmunología , Proteína C/inmunología , Animales , Antígenos CD/inmunología , Antígenos CD/metabolismo , Modelos Animales de Enfermedad , Receptor de Proteína C Endotelial , Escherichia coli , Infecciones por Escherichia coli/sangre , Infecciones por Escherichia coli/inmunología , Trampas Extracelulares/metabolismo , Femenino , Humanos , Antígeno de Macrófago-1/inmunología , Antígeno de Macrófago-1/metabolismo , Masculino , Activación Neutrófila/efectos de los fármacos , Neutrófilos/metabolismo , Papio anubis , Proteína C/metabolismo , Receptores de Superficie Celular/inmunología , Receptores de Superficie Celular/metabolismo , Sepsis/sangre , Sepsis/inmunología , Acetato de Tetradecanoilforbol/farmacología
15.
Pediatr Blood Cancer ; 65(2)2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28988427

RESUMEN

INTRODUCTION: Despite the demonstrated efficacy of hydroxyurea therapy, children with sickle cell anaemia in the UK are preferentially managed with supportive care or transfusion. Hydroxyurea is reserved for children with severe disease phenotype. This is in contrast to North America and other countries where hydroxyurea is widely used for children of all clinical phenotypes. The conservative UK practice may in part be due to concerns about toxicity, in particular marrow suppression with high doses, and growth in children. METHODS AND RESULTS: We monitored 37 paediatric patients with sickle cell anaemia who were treated with hydroxyurea at a single UK treatment centre. Therapy was well tolerated and mild transient cytopenias were the only toxicity observed. Comparative analysis of patients receiving ≥26 mg/kg/day versus <26 mg/kg/day demonstrates increasing dose has a significant positive effect on foetal haemoglobin (Hb; 29.2% vs. 20.4%, P = 0.0151), mean cell volume (94.4 vs. 86.5, P = 0.0183) and reticulocyte count (99.66 × 109 /l vs. 164.3 × 109 /l, P = 0.0059). Marrow suppression was not a clinical problem with high-dose treatment, Hb 92.25 g/l versus 91.81 g/l (ns), neutrophil count 3.3 × 109 /l versus 4.8 × 109 /l (ns) and platelet count 232.4 × 109 /l versus 302.2 × 109 /l (ns). Normal growth rates were maintained in all children. Good adherence to therapy was a significant factor in reducing hospitalisations. CONCLUSION: This study demonstrates the effectiveness and safety in practice of high-dose hydroxyurea as a disease-modifying therapy, which we advocate for all children with sickle cell anaemia.


Asunto(s)
Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/tratamiento farmacológico , Hidroxiurea/administración & dosificación , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Reino Unido
16.
Ann Surg ; 266(5): 720-728, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28742713

RESUMEN

OBJECTIVE: This randomized controlled trial (RCT) hypothesized that prolonged enteral nutrition (EN) with supplemental eicosapentanoic acid (EPA), an omega-3 fatty acid with immune and anabolic properties, may impact on clinical and nutritional outcomes. BACKGROUND: Esophagectomy is associated with significant weight loss and catabolism, and negatively impacts quality of life (QL). Strategies to counter sustained catabolism have therapeutic rationale. METHODS: This multicenter, double-blind, placebo-controlled RCT was powered on a 5% difference in lean body mass (LBM) at 1 month. Patients were randomly assigned to receive either EN-EPA (2.2 g EPA/day) (n = 97) or isocaloric isonitrogenous standard EN (EN-S) (n = 94), preoperatively (5 days orally), and postoperatively via a jejunostomy until 1 month postdischarge. Assessments perioperatively, and at 1, 3, and 6 months included weight, body mass index (BMI), body composition, muscle strength, cytokines, complications, and QL. RESULTS: The median (range) nutrition support was for 51 (36 to 78) days, and overall compliance was 96%. For the entire cohort, a significant (P < 0.005) decrease in weight (-7.4 ±â€Š6.6 kg), BMI (-2.6 ±â€Š2.2 kg/m), LBM (-2.5 ±â€Š8.7 kg), and fat mass (-3.4 ±â€Š5.8 kg) was evident from preoperatively to 6 months. The mean (±SD) loss of LBM (kg) at 1 month was -3.7 ±â€Š8.7 in the EN-S group, compared with -5.6 ±â€Š12.1 in the EN-EPA group (P = 0.355). Per-protocol analysis revealed no difference between the EN-EPA and EN-S in any clinical, nutritional, functional, QL or immune parameter at any time point. CONCLUSIONS: The thesis that EPA impacts on anabolism, immune function, and clinical outcomes post-esophagectomy was not supported. Compliance with home EN was excellent, but weight, muscle, and fat loss was significant in 30% of patients, highlighting the complexity of postoperative weight loss.


Asunto(s)
Suplementos Dietéticos , Ácido Eicosapentaenoico/uso terapéutico , Nutrición Enteral/métodos , Esofagectomía , Desnutrición/prevención & control , Cuidados Posoperatorios/métodos , Complicaciones Posoperatorias/prevención & control , Método Doble Ciego , Estudios de Seguimiento , Humanos , Desnutrición/diagnóstico , Desnutrición/etiología , Complicaciones Posoperatorias/diagnóstico , Estudios Prospectivos , Calidad de Vida , Factores de Tiempo , Resultado del Tratamiento , Pérdida de Peso
17.
Am J Physiol Cell Physiol ; 310(7): C568-75, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26764050

RESUMEN

Molecular chaperones that support protein quality control, including heat shock protein 70 (Hsp70), participate in diverse aspects of cellular and physiological function. Recent studies have reported roles for specific chaperone activities in blood platelets in maintaining hemostasis; however, the functions of Hsp70 in platelet physiology remain uninvestigated. Here we characterize roles for Hsp70 activity in platelet activation and function. In vitro biochemical, microscopy, flow cytometry, and aggregometry assays of platelet function, as well as ex vivo analyses of platelet aggregate formation in whole blood under shear, were carried out under Hsp70-inhibited conditions. Inhibition of platelet Hsp70 blocked platelet aggregation and granule secretion in response to collagen-related peptide (CRP), which engages the immunoreceptor tyrosine-based activation motif-bearing collagen receptor glycoprotein VI (GPVI)-Fc receptor-γ chain complex. Hsp70 inhibition also reduced platelet integrin-αIIbß3 activation downstream of GPVI, as Hsp70-inhibited platelets showed reduced PAC-1 and fibrinogen binding. Ex vivo, pharmacological inhibition of Hsp70 in human whole blood prevented the formation of platelet aggregates on collagen under shear. Biochemical studies supported a role for Hsp70 in maintaining the assembly of the linker for activation of T cells signalosome, which couples GPVI-initiated signaling to integrin activation, secretion, and platelet function. Together, our results suggest that Hsp70 regulates platelet activation and function by supporting linker for activation of T cells-associated signaling events downstream of platelet GPVI engagement, suggesting a role for Hsp70 in the intracellular organization of signaling systems that mediate platelet secretion, "inside-out" activation of platelet integrin-αIIbß3, platelet-platelet aggregation, and, ultimately, hemostatic plug and thrombus formation.


Asunto(s)
Plaquetas/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Integrinas/metabolismo , Activación Plaquetaria/fisiología , Agregación Plaquetaria/fisiología , Citometría de Flujo , Humanos , Transducción de Señal/fisiología
18.
Am J Physiol Cell Physiol ; 310(5): C373-80, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26659727

RESUMEN

The Tec family kinase Bruton's tyrosine kinase (Btk) plays an important signaling role downstream of immunoreceptor tyrosine-based activation motifs in hematopoietic cells. Mutations in Btk are involved in impaired B-cell maturation in X-linked agammaglobulinemia, and Btk has been investigated for its role in platelet activation via activation of the effector protein phospholipase Cγ2 downstream of the platelet membrane glycoprotein VI (GPVI). Because of its role in hematopoietic cell signaling, Btk has become a target in the treatment of chronic lymphocytic leukemia and mantle cell lymphoma; the covalent Btk inhibitor ibrutinib was recently approved by the US Food and Drug Administration for treatment of these conditions. Antihemostatic events have been reported in some patients taking ibrutinib, although the mechanism of these events remains unknown. We sought to determine the effects of Btk inhibition on platelet function in a series of in vitro studies of platelet activation, spreading, and aggregation. Our results show that irreversible inhibition of Btk with two ibrutinib analogs in vitro decreased human platelet activation, phosphorylation of Btk, P-selectin exposure, spreading on fibrinogen, and aggregation under shear flow conditions. Short-term studies of ibrutinib analogs administered in vivo also showed abrogation of platelet aggregation in vitro, but without measurable effects on plasma clotting times or on bleeding in vivo. Taken together, our results suggest that inhibition of Btk significantly decreased GPVI-mediated platelet activation, spreading, and aggregation in vitro; however, prolonged bleeding was not observed in a model of bleeding.


Asunto(s)
Plaquetas/efectos de los fármacos , Activación Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/efectos de los fármacos , Glicoproteínas de Membrana Plaquetaria/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Administración Oral , Agammaglobulinemia Tirosina Quinasa , Animales , Plaquetas/metabolismo , Hemorragia/inducido químicamente , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Papio , Activación Plaquetaria/fisiología , Transducción de Señal/efectos de los fármacos
19.
Blood ; 133(5): 385-386, 2019 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-30705047
20.
J Toxicol Pathol ; 29(3 Suppl): 49S-103S, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27621538

RESUMEN

The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) Project (www.toxpath.org/inhand.asp) is an initiative of the Societies of Toxicological Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP) and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature for classifying microscopic lesions observed in the skeletal tissues and teeth of laboratory rats and mice, with color photomicrographs illustrating examples of many common lesions. The standardized nomenclature presented in this document is also available on the internet (http://www.goreni.org/). Sources of material were databases from government, academic and industrial laboratories throughout the world.

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