Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 65
Filtrar
1.
Macromol Rapid Commun ; 44(10): e2200973, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36964967

RESUMO

Epoxy to copper adhesion supports the reliability of numerous structures in electronic packaging. Compared to substrate pre-treatment, processing and cost considerations are in favor of adhesion promoters loaded in epoxy formulations. In this work, first row transition metal ß-diketonates present such a compelling case when added in epoxy/anhydride resins: over 30% (before moisture aging) and 50% (after moisture aging) enhancement in lap shear strength are found using Co(II) and Ni(II) hexafluoroacetylacetonate. From extensive X-ray photoelectron spectroscopy (XPS) analyses on the adhesively failed sample surfaces, increased population of oxygen-containing functional groups, especially esters, is linked to the adhesion improvement. Assisted by XPS depth profile on the fractured epoxy side and in situ Fourier-transform infrared spectroscopy (FTIR), the previously discovered latent cure characteristics endowed by the metal chelates interacting with phosphine catalysts are regarded pivotal for pacing the anhydride consumption and allowing interfacial esterification reactions to occur. Further examinations on the XPS binding energy shifts and dielectric properties of the doped epoxy also reveal metal-polymer coordination that contribute to the adhesion and moisture resistance properties. These findings should stimulate future research of functional additives targeting at cure kinetics control and polar group coordination ideas for more robust epoxy-Cu joints.


Assuntos
Anidridos , Resinas Epóxi , Resinas Epóxi/química , Reprodutibilidade dos Testes , Polímeros , Metais
2.
Int J Mol Sci ; 23(6)2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35328390

RESUMO

Cardiovascular disease is the leading cause of mortality globally with at least 26 million people worldwide living with heart failure (HF). Metabolism has been an active area of investigation in the setting of HF since the heart demands a high rate of ATP turnover to maintain homeostasis. With the advent of -omic technologies, specifically metabolomics and lipidomics, HF pathologies have been better characterized with unbiased and holistic approaches. These techniques have identified novel pathways in our understanding of progression of HF and potential points of intervention. Furthermore, sodium-glucose transport protein 2 inhibitors, a drug that has changed the dogma of HF treatment, has one of the strongest types of evidence for a potential metabolic mechanism of action. This review will highlight cardiac metabolism in both the healthy and failing heart and then discuss the metabolic effects of heart failure drugs.


Assuntos
Doenças Cardiovasculares , Insuficiência Cardíaca , Coração , Insuficiência Cardíaca/metabolismo , Humanos
3.
Brain ; 143(9): 2664-2672, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32537631

RESUMO

Magnetic resonance guided high intensity focused ultrasound is a novel, non-invasive, image-guided procedure that is able to ablate intracranial tissue with submillimetre precision. It is currently FDA approved for essential tremor and tremor dominant Parkinson's disease. The aim of this update is to review the limitations of current landmark-based targeting techniques of the ventral intermediate nucleus and demonstrate the role of emerging imaging techniques that are relevant for both magnetic resonance guided high intensity focused ultrasound and deep brain stimulation. A significant limitation of standard MRI sequences is that the ventral intermediate nucleus, dentatorubrothalamic tract, and other deep brain nuclei cannot be clearly identified. This paper provides original, annotated images demarcating the ventral intermediate nucleus, dentatorubrothalamic tract, and other deep brain nuclei on advanced MRI sequences such as fast grey matter acquisition T1 inversion recovery, quantitative susceptibility mapping, susceptibility weighted imaging, and diffusion tensor imaging tractography. Additionally, the paper reviews clinical efficacy of targeting with these novel MRI techniques when compared to current established landmark-based targeting techniques. The paper has widespread applicability to both deep brain stimulation and magnetic resonance guided high intensity focused ultrasound.


Assuntos
Tremor Essencial/diagnóstico por imagem , Tremor Essencial/terapia , Tratamento por Ondas de Choque Extracorpóreas/métodos , Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/terapia , Estimulação Encefálica Profunda/métodos , Globo Pálido/diagnóstico por imagem , Humanos
4.
Am J Physiol Heart Circ Physiol ; 318(1): H25-H33, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31774696

RESUMO

Ex situ heart perfusion (ex situ heart perfusion) is an emerging technique that aims to increase the number of organs available for transplantation by augmenting both donor heart preservation and evaluation. Traditionally, ex situ heart perfusion has been performed in an unloaded Langendorff mode, though more recently groups have begun to use pump-supported working mode (PSWM) and passive afterload working mode (PAWM) to enable contractile evaluation during ex situ heart perfusion. To this point, however, neither the predictive effectiveness of the two working modes nor the predictive power of individual contractile parameters has been analyzed. In this article, we use our previously described system to analyze the predictive relevance of a multitude of contractile parameters measured in each working mode. Ten porcine hearts were excised and perfused ex situ in Langendorff mode for 4 h, evaluated using pressure-volume catheterization in both PSWM and PAWM, and transplanted into size-matched recipient pigs. After 3 h, hearts were weaned from cardiopulmonary bypass and evaluated. When correlating posttransplant measurements to their ex situ counterparts, we report that parameters measured in both modes show sufficient power (Spearman rank coefficient > 0.7) in predicting global posttransplant function, characterized by cardiac index and preload recruitable stroke work. For the prediction of specific posttransplant systolic and diastolic function, however, a large discrepancy between the two working modes was observed. With 9 of 10 measured posttransplant parameters showing stronger correlation with counterparts measured in PAWM, it is concluded that PAWM allows for a more detailed and nuanced prediction of posttransplant function than can be made in PSWM.NEW & NOTEWORTHY Ex situ heart perfusion has been proposed as a means to augment the organ donor pool by improving organ preservation and evaluation between donation and transplantation. Using our multimodal perfusion system, we analyzed the impact of using a "passive afterload working mode" for functional evaluation as compared with the more traditional "pump-supported working mode." Our data suggests that passive afterload working mode allows for a more nuanced prediction of posttransplant function in porcine hearts.


Assuntos
Transplante de Coração , Contração Miocárdica , Perfusão , Função Ventricular Esquerda , Pressão Ventricular , Animais , Cateterismo Cardíaco , Diástole , Transplante de Coração/efeitos adversos , Preparação de Coração Isolado , Masculino , Modelos Animais , Perfusão/efeitos adversos , Valor Preditivo dos Testes , Recuperação de Função Fisiológica , Sus scrofa , Sístole , Fatores de Tempo
5.
Emerg Radiol ; 27(6): 747-754, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32778985

RESUMO

Novel coronavirus disease (COVID-19) was declared a global pandemic on March 1, 2020. Neurological manifestations are now being reported worldwide, including emergent presentation with acute neurological changes as well as a comorbidity in hospitalized patients. There is limited knowledge on the neurologic manifestations of COVID-19 at present, with a wide array of neurological complications reported, ranging from ischemic stroke to acute demyelination and encephalitis. We report five cases of COVID-19 presenting to the ER with acute neurological symptoms, over the course of 1 month. This includes two cases of ischemic stroke, one with large-vessel occlusion and one with embolic infarcts. The remainders of the cases include acute tumefactive demyelination, isolated cytotoxic edema of the corpus callosum with subarachnoid hemorrhage, and posterior reversible encephalopathy syndrome (PRES).


Assuntos
Encefalopatias/diagnóstico por imagem , Encefalopatias/virologia , Infecções por Coronavirus/complicações , Emergências , Neuroimagem/métodos , Pneumonia Viral/complicações , Adulto , Idoso , Betacoronavirus , Encefalopatias/terapia , COVID-19 , Angiografia Cerebral , Angiografia por Tomografia Computadorizada , Infecções por Coronavirus/terapia , Evolução Fatal , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pandemias , Pneumonia Viral/terapia , Síndrome da Leucoencefalopatia Posterior/diagnóstico por imagem , Síndrome da Leucoencefalopatia Posterior/terapia , Síndrome da Leucoencefalopatia Posterior/virologia , SARS-CoV-2 , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/virologia
6.
Nature ; 489(7416): 385-90, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-22914087

RESUMO

Haploinsufficiency of the SCN1A gene encoding voltage-gated sodium channel Na(V)1.1 causes Dravet's syndrome, a childhood neuropsychiatric disorder including recurrent intractable seizures, cognitive deficit and autism-spectrum behaviours. The neural mechanisms responsible for cognitive deficit and autism-spectrum behaviours in Dravet's syndrome are poorly understood. Here we report that mice with Scn1a haploinsufficiency exhibit hyperactivity, stereotyped behaviours, social interaction deficits and impaired context-dependent spatial memory. Olfactory sensitivity is retained, but novel food odours and social odours are aversive to Scn1a(+/-) mice. GABAergic neurotransmission is specifically impaired by this mutation, and selective deletion of Na(V)1.1 channels in forebrain interneurons is sufficient to cause these behavioural and cognitive impairments. Remarkably, treatment with low-dose clonazepam, a positive allosteric modulator of GABA(A) receptors, completely rescued the abnormal social behaviours and deficits in fear memory in the mouse model of Dravet's syndrome, demonstrating that they are caused by impaired GABAergic neurotransmission and not by neuronal damage from recurrent seizures. These results demonstrate a critical role for Na(V)1.1 channels in neuropsychiatric functions and provide a potential therapeutic strategy for cognitive deficit and autism-spectrum behaviours in Dravet's syndrome.


Assuntos
Transtorno Autístico/tratamento farmacológico , Transtorno Autístico/fisiopatologia , Moduladores GABAérgicos/uso terapêutico , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Canais de Sódio/genética , Canais de Sódio/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Ácido gama-Aminobutírico/metabolismo , Animais , Ansiedade/fisiopatologia , Transtorno Autístico/complicações , Transtorno Autístico/genética , Clonazepam/farmacologia , Clonazepam/uso terapêutico , Epilepsias Mioclônicas/complicações , Epilepsias Mioclônicas/genética , Epilepsias Mioclônicas/fisiopatologia , Moduladores GABAérgicos/farmacologia , Neurônios GABAérgicos/metabolismo , Haploinsuficiência/genética , Heterozigoto , Hipocampo/citologia , Proteínas de Homeodomínio/genética , Hipercinese/fisiopatologia , Interneurônios/metabolismo , Masculino , Memória , Camundongos , Canal de Sódio Disparado por Voltagem NAV1.1 , Comportamento Social , Percepção Espacial , Transtorno de Movimento Estereotipado/fisiopatologia , Síndrome , Fatores de Transcrição/genética
7.
Neurobiol Dis ; 73: 106-17, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25281316

RESUMO

Dominant loss-of-function mutations in voltage-gated sodium channel NaV1.1 cause Dravet Syndrome, an intractable childhood-onset epilepsy. NaV1.1(+/-) Dravet Syndrome mice in C57BL/6 genetic background exhibit severe seizures, cognitive and social impairments, and premature death. Here we show that Dravet Syndrome mice in pure 129/SvJ genetic background have many fewer seizures and much less premature death than in pure C57BL/6 background. These mice also have a higher threshold for thermally induced seizures, fewer myoclonic seizures, and no cognitive impairment, similar to patients with Genetic Epilepsy with Febrile Seizures Plus. Consistent with this mild phenotype, mutation of NaV1.1 channels has much less physiological effect on neuronal excitability in 129/SvJ mice. In hippocampal slices, the excitability of CA1 Stratum Oriens interneurons is selectively impaired, while the excitability of CA1 pyramidal cells is unaffected. NaV1.1 haploinsufficiency results in increased rheobase and threshold for action potential firing and impaired ability to sustain high-frequency firing. Moreover, deletion of NaV1.1 markedly reduces the amplification and integration of synaptic events, further contributing to reduced excitability of interneurons. Excitability is less impaired in inhibitory neurons of Dravet Syndrome mice in 129/SvJ genetic background. Because specific deletion of NaV1.1 in forebrain GABAergic interneuons is sufficient to cause the symptoms of Dravet Syndrome in mice, our results support the conclusion that the milder phenotype in 129/SvJ mice is caused by lesser impairment of sodium channel function and electrical excitability in their forebrain interneurons. This mild impairment of excitability of interneurons leads to a milder disease phenotype in 129/SvJ mice, similar to Genetic Epilepsy with Febrile Seizures Plus in humans.


Assuntos
Epilepsias Mioclônicas/genética , Epilepsias Mioclônicas/patologia , Mutação/genética , Canal de Sódio Disparado por Voltagem NAV1.1/genética , Inibição Neural/genética , Potenciais de Ação/genética , Animais , Animais Recém-Nascidos , Fenômenos Biofísicos/genética , Condicionamento Psicológico/fisiologia , Modelos Animais de Doenças , Epilepsias Mioclônicas/etiologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/genética , Medo/psicologia , Hipocampo/citologia , Hipertermia Induzida/efeitos adversos , Técnicas In Vitro , Lidocaína/análogos & derivados , Lidocaína/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Inibição Neural/fisiologia , Bloqueadores dos Canais de Sódio/farmacologia
8.
Proc Natl Acad Sci U S A ; 109(6): E368-77, 2012 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-22223655

RESUMO

Na(V)1.1 is the primary voltage-gated Na(+) channel in several classes of GABAergic interneurons, and its reduced activity leads to reduced excitability and decreased GABAergic tone. Here, we show that Na(V)1.1 channels are expressed in the suprachiasmatic nucleus (SCN) of the hypothalamus. Mice carrying a heterozygous loss of function mutation in the Scn1a gene (Scn1a(+/-)), which encodes the pore-forming α-subunit of the Na(V)1.1 channel, have longer circadian period than WT mice and lack light-induced phase shifts. In contrast, Scn1a(+/-) mice have exaggerated light-induced negative-masking behavior and normal electroretinogram, suggesting an intact retina light response. Scn1a(+/-) mice show normal light induction of c-Fos and mPer1 mRNA in ventral SCN but impaired gene expression responses in dorsal SCN. Electrical stimulation of the optic chiasm elicits reduced calcium transients and impaired ventro-dorsal communication in SCN neurons from Scn1a(+/-) mice, and this communication is barely detectable in the homozygous gene KO (Scn1a(-/-)). Enhancement of GABAergic transmission with tiagabine plus clonazepam partially rescues the effects of deletion of Na(V)1.1 on circadian period and phase shifting. Our report demonstrates that a specific voltage-gated Na(+) channel and its associated impairment of SCN interneuronal communication lead to major deficits in the function of the master circadian pacemaker. Heterozygous loss of Na(V)1.1 channels is the underlying cause for severe myoclonic epilepsy of infancy; the circadian deficits that we report may contribute to sleep disorders in severe myoclonic epilepsy of infancy patients.


Assuntos
Comunicação Celular , Ritmo Circadiano/fisiologia , Espaço Extracelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Canais de Sódio/metabolismo , Núcleo Supraquiasmático/citologia , Núcleo Supraquiasmático/metabolismo , Animais , Comportamento Animal/efeitos da radiação , Proteínas CLOCK/genética , Proteínas CLOCK/metabolismo , Comunicação Celular/genética , Comunicação Celular/efeitos da radiação , Ritmo Circadiano/genética , Ritmo Circadiano/efeitos da radiação , Eletrorretinografia , Espaço Extracelular/efeitos da radiação , Feminino , Neurônios GABAérgicos/citologia , Neurônios GABAérgicos/metabolismo , Regulação da Expressão Gênica/efeitos da radiação , Luz , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Canal de Sódio Disparado por Voltagem NAV1.1 , Fenótipo , Estimulação Luminosa , Transdução de Sinais/genética , Núcleo Supraquiasmático/efeitos da radiação , Transmissão Sináptica/genética , Transmissão Sináptica/efeitos da radiação
9.
Proc Natl Acad Sci U S A ; 109(36): 14646-51, 2012 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-22908258

RESUMO

Heterozygous loss-of-function mutations in the brain sodium channel Na(V)1.1 cause Dravet syndrome (DS), a pharmacoresistant infantile-onset epilepsy syndrome with comorbidities of cognitive impairment and premature death. Previous studies using a mouse model of DS revealed reduced sodium currents and impaired excitability in GABAergic interneurons in the hippocampus, leading to the hypothesis that impaired excitability of GABAergic inhibitory neurons is the cause of epilepsy and premature death in DS. However, other classes of GABAergic interneurons are less impaired, so the direct cause of hyperexcitability, epilepsy, and premature death has remained unresolved. We generated a floxed Scn1a mouse line and used the Cre-Lox method driven by an enhancer from the Dlx1,2 locus for conditional deletion of Scn1a in forebrain GABAergic neurons. Immunocytochemical studies demonstrated selective loss of Na(V)1.1 channels in GABAergic interneurons in cerebral cortex and hippocampus. Mice with this deletion died prematurely following generalized tonic-clonic seizures, and they were equally susceptible to thermal induction of seizures as mice with global deletion of Scn1a. Evidently, loss of Na(V)1.1 channels in forebrain GABAergic neurons is both necessary and sufficient to cause epilepsy and premature death in DS.


Assuntos
Epilepsias Mioclônicas/genética , Interneurônios/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.1/deficiência , Animais , Eletrocardiografia , Eletroencefalografia , Epilepsias Mioclônicas/patologia , Hipocampo/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Transgênicos , Mutação/genética , Canal de Sódio Disparado por Voltagem NAV1.1/genética , Plasmídeos/genética , Prosencéfalo/metabolismo
10.
Exp Cell Res ; 319(3): 153-60, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23063429

RESUMO

Gö6976 is a nonglycosidic indolocarbazole compound widely used as a specific inhibitor of PKCα/ß. In experiments probing for a role of PKCα in human laminin-2-integrin-mediated cell adhesion and spreading of PC12 cells, we observed unexpected enhancements of adhesion, spreading and stress fiber formation to 1 µM Gö6976 with concomitant increase in membrane translocation of PKCδ and autophosphorylation of focal adhesion kinase (FAK). Importantly, enhanced cellular behavior and membrane translocation of PKCδ induced by Gö6976 was retained in siRNA-transfected PC12 cells to knockdown PKCα expression. Gö6976 also induced laminin-dependent cell adhesion in NIH/3T3 and CV-1 fibroblasts, suggesting of a mechanism that may be common to multiple cell-types. A specific inhibitor of PKCδ, rottlerin, completely abrogated Gö6976-dependent increase in PC12 cell adhesion to laminin as well as the activation of small GTPases, Rac1 and Cdc42, that are downstream of PKCδ in adhesion receptor signaling. siRNA knockdown of Rac1 and Cdc42 expression inhibited cell spreading and lamellipodia formation in PC12 cells. Overall, these results suggest that Gö6976 may stimulate membrane recruitment of PKCδ through a mechanism that is independent of PKCα/ß signaling. In addition, the activation of Rac1 and Cdc42 by human laminin-2-integrin-dependent activation of PKCδ/FAK signaling mediates cell spreading and lamellipodia formation in PC12 cells.


Assuntos
Carbazóis/farmacologia , Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proteína Quinase C-delta/fisiologia , Animais , Adesão Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Membrana Celular/fisiologia , Células Cultivadas , Chlorocebus aethiops , Ativação Enzimática/efeitos dos fármacos , Células HEK293 , Humanos , Camundongos , Células NIH 3T3 , Células PC12 , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C beta , Proteína Quinase C-alfa/antagonistas & inibidores , Proteína Quinase C-delta/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Ratos , Regulação para Cima/efeitos dos fármacos
11.
Proc Natl Acad Sci U S A ; 108(18): 7296-301, 2011 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-21504943

RESUMO

We present a lens-free optical tomographic microscope, which enables imaging a large volume of approximately 15 mm(3) on a chip, with a spatial resolution of < 1 µm × < 1 µm × < 3 µm in x, y and z dimensions, respectively. In this lens-free tomography modality, the sample is placed directly on a digital sensor array with, e.g., ≤ 4 mm distance to its active area. A partially coherent light source placed approximately 70 mm away from the sensor is employed to record lens-free in-line holograms of the sample from different viewing angles. At each illumination angle, multiple subpixel shifted holograms are also recorded, which are digitally processed using a pixel superresolution technique to create a single high-resolution hologram of each angular projection of the object. These superresolved holograms are digitally reconstructed for an angular range of ± 50°, which are then back-projected to compute tomograms of the sample. In order to minimize the artifacts due to limited angular range of tilted illumination, a dual-axis tomography scheme is adopted, where the light source is rotated along two orthogonal axes. Tomographic imaging performance is quantified using microbeads of different dimensions, as well as by imaging wild-type Caenorhabditis elegans. Probing a large volume with a decent 3D spatial resolution, this lens-free optical tomography platform on a chip could provide a powerful tool for high-throughput imaging applications in, e.g., cell and developmental biology.


Assuntos
Holografia/instrumentação , Microscopia/instrumentação , Tomografia/instrumentação , Animais , Caenorhabditis elegans/ultraestrutura
12.
Curr Pharm Teach Learn ; 16(5): 297-299, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38594169

RESUMO

INTRODUCTION: Student readiness for Advanced Pharmacy Practice Experiences (APPEs) has not been explicitly defined in literature or standards. Readiness for APPEs is a programmatic requirement of all schools and colleges of pharmacy (schools), leaving schools to determine their own assessments of APPE readiness. Current literature provides no consensus on the definition of APPE readiness nor the assessments or benchmarks used to evaluate APPE readiness. Schools have an opportunity to improve efforts to identify students at risk for poor APPE performance and provide early intervention. COMMENTARY: Due to a lack of consensus, it may be easier to describe students who are not ready for APPEs than it is to describe students who are APPE ready. APPE unreadiness is defined by the authors as those who require significant preceptor instruction on foundational competencies such as knowledge, skills, and/or attitudes and therefore are unable to meaningfully engage in application-based patient care activities. By adding focus to APPE unreadiness within APPE readiness programs, pharmacy schools may be able to more readily identify and remediate students who are at risk of failing one or more APPE rotations. IMPLICATIONS: We provide four recommendations for schools to consider. These are focused on assessing APPE readiness to qualify and quantify APPE unready students. By assessing APPE unreadiness, schools can make continuous quality improvement to ensure that preceptors, sites, students, and faculty can have the ongoing confidence that APPE students are all ready to meaningfully engage on rotation.


Assuntos
Educação em Farmácia , Assistência Farmacêutica , Farmácia , Humanos , Currículo , Aprendizagem Baseada em Problemas
13.
Transplantation ; 108(1): 184-191, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37505906

RESUMO

BACKGROUND: Ex vivo machine perfusion is a novel preservation technique for storing and assessing marginal kidney grafts. All ex vivo perfusion techniques have advantages and shortcomings. The current study analyzed whether a combination of oxygenated hypothermic machine perfusion (oxHMP) followed by a short period of normothermic ex vivo kidney perfusion (NEVKP) could combine the advantages of both techniques. METHODS: Porcine kidneys were exposed to 30 min of warm ischemia followed by perfusion. Kidneys underwent either 16-h NEVKP or 16-h oxHMP. The third group was exposed to 16-h oxHMP followed by 3-h NEVKP (oxHMP + NEVKP group). After contralateral nephrectomy, grafts were autotransplanted and animals were followed up for 8 d. RESULTS: All animals survived the follow-up period. Grafts preserved by continuous NEVKP showed improved function with lower peak serum creatinine and more rapid recovery compared with the other 2 groups. Urine neutrophil gelatinase-associated lipocalin, a marker of kidney injury, was found to be significantly lowered on postoperative day 3 in the oxHMP + NEVKP group compared with the other 2 groups. CONCLUSIONS: A short period of NEVKP after oxHMP provides comparable short-term outcomes to prolonged NEVKP and is superior to oxHMP alone. A combination of oxHMP with end-ischemic NEVKP could be an attractive, practical strategy to combine the advantages of both preservation techniques.


Assuntos
Transplante de Rim , Suínos , Animais , Transplante de Rim/efeitos adversos , Transplante de Rim/métodos , Preservação de Órgãos/métodos , Modelos Animais , Rim/cirurgia , Perfusão/efeitos adversos , Perfusão/métodos
14.
JACC Adv ; 3(2): 100777, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38939405

RESUMO

Background: Previous studies have linked cardiovascular risk factors during midlife to cognitive function in later life. However, few studies have looked at the association between cardiac function, brain structure, and cognitive function and even less have included diverse middle-aged populations. Objectives: The objective of this study was to determine associations between cardiac and brain structure and function in a multiethnic cohort of middle-aged adults. Methods: A cross-sectional study was conducted in participants of the Dallas Heart Study phase 2 (N = 1,919; 46% Black participants). Left ventricular (LV) mass, LV ejection fraction, LV concentricity, and peak systolic strain (LV Ecc) were assessed by cardiac magnetic resonance imaging. White matter hyperintensities (WMH) volume was measured by fluid attenuated inversion recovery magnetic resonance imaging. The Montreal Cognitive Assessment was used to measure cognitive functioning. Associations between cardiac and brain measures were determined using multivariable linear regression after adjusting for cardiovascular risk factors, education level, and physical activity. Results: LV ejection fraction was associated with total Montreal Cognitive Assessment score (ß = 0.06 [95% CI: 0.003-0.12], P = 0.042) and LV Ecc was associated with WMH volume (ß = 0.08 [95% CI: 0.01-0.14], P = 0.025) in the overall cohort without significant interaction by race/ethnicity. Higher LV mass and concentricity were associated with larger WMH volume in the overall cohort (ß = 0.13 [95% CI: 0.03-0.23], P = 0.008 and 0.10 [95% CI: 0.03-0.17], P = 0.005). These associations were more predominant in Black than White participants (ß = 0.17 [95% CI: 0.04-0.30] vs ß = -0.009 [95% CI: -0.16 to 0.14], P = 0.036 and ß = 0.22 [95% CI: 0.13-0.32] vs ß = -0.11 [95% CI: -0.21 to -0.01], P < 0.0001, for LV mass and concentricity, respectively). Conclusions: Subclinical cardiac dysfunction indicated by LVEF was associated with lower cognitive function. Moreover, LV mass and concentric remodeling were associated with higher WMH burden, particularly among Black individuals.

16.
J Biol Chem ; 286(14): 12627-39, 2011 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21224388

RESUMO

Regulation of CaV1.2 channels in cardiac myocytes by the ß-adrenergic pathway requires a signaling complex in which the proteolytically processed distal C-terminal domain acts as an autoinhibitor of channel activity and mediates up-regulation by the ß-adrenergic receptor and PKA bound to A-kinase anchoring protein 15 (AKAP15). We examined the significance of this distal C-terminal signaling complex for CaV1.2 and CaV1.3 channels in neurons. AKAP15 co-immunoprecipitates with CaV1.2 and CaV1.3 channels. AKAP15 has overlapping localization with CaV1.2 and CaV1.3 channels in cell bodies and proximal dendrites and is closely co-localized with CaV1.2 channels in punctate clusters. The neuronal AKAP MAP2B, which also interacts with CaV1.2 and CaV1.3 channels, has complementary localization to AKAP15, suggesting different functional roles in calcium channel regulation. Studies with mice that lack the distal C-terminal domain of CaV1.2 channels (CaV1.2ΔDCT) reveal that AKAP15 interacts with neuronal CaV1.2 channels via their C terminus in vivo and is co-localized in punctate clusters of CaV1.2 channels via that interaction. CaV1.2ΔDCT neurons have reduced L-type calcium current, indicating that the distal C-terminal domain is required for normal functional expression in vivo. Deletion of the distal C-terminal domain impairs calcium-dependent signaling from CaV1.2 channels to the nucleus, as shown by reduction in phosphorylation of the cAMP response element-binding protein. Our results define AKAP signaling complexes of CaV1.2 and CaV1.3 channels in brain and reveal three previously unrecognized functional roles for the distal C terminus of neuronal CaV1.2 channels in vivo: increased functional expression, anchoring of AKAP15 and PKA, and initiation of excitation-transcription coupling.


Assuntos
Proteínas de Ancoragem à Quinase A/metabolismo , Encéfalo/citologia , Canais de Cálcio Tipo L/metabolismo , Neurônios/metabolismo , Proteínas de Ancoragem à Quinase A/genética , Animais , Canais de Cálcio Tipo L/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Eletroforese em Gel de Poliacrilamida , Eletrofisiologia , Hipocampo/citologia , Immunoblotting , Imuno-Histoquímica , Imunoprecipitação , Camundongos , Camundongos Mutantes , Fosforilação , Ligação Proteica , Receptores Adrenérgicos beta 2/genética , Receptores Adrenérgicos beta 2/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
17.
J Biol Chem ; 286(14): 12617-26, 2011 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21216955

RESUMO

L-type calcium currents conducted by CaV1.2 channels initiate excitation-contraction coupling in cardiac and vascular smooth muscle. In the heart, the distal portion of the C terminus (DCT) is proteolytically processed in vivo and serves as a noncovalently associated autoinhibitor of CaV1.2 channel activity. This autoinhibitory complex, with A-kinase anchoring protein-15 (AKAP15) bound to the DCT, is hypothesized to serve as the substrate for ß-adrenergic regulation in the fight-or-flight response. Mice expressing CaV1.2 channels with the distal C terminus deleted (DCT-/-) develop cardiac hypertrophy and die prematurely after E15. Cardiac hypertrophy and survival rate were improved by drug treatments that reduce peripheral vascular resistance and hypertension, consistent with the hypothesis that CaV1.2 hyperactivity in vascular smooth muscle causes hypertension, hypertrophy, and premature death. However, in contrast to expectation, L-type Ca2+ currents in cardiac myocytes from DCT-/- mice were dramatically reduced due to decreased cell-surface expression of CaV1.2 protein, and the voltage dependence of activation and the kinetics of inactivation were altered. CaV1.2 channels in DCT-/- myocytes fail to respond to activation of adenylyl cyclase by forskolin, and the localized expression of AKAP15 is reduced. Therefore, we conclude that the DCT of CaV1.2 channels is required in vivo for normal vascular regulation, cell-surface expression of CaV1.2 channels in cardiac myocytes, and ß-adrenergic stimulation of L-type Ca2+ currents in the heart.


Assuntos
Canais de Cálcio Tipo L/química , Canais de Cálcio Tipo L/metabolismo , Insuficiência Cardíaca/metabolismo , Proteínas de Ancoragem à Quinase A/genética , Proteínas de Ancoragem à Quinase A/metabolismo , Animais , Canais de Cálcio Tipo L/genética , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Eletrofisiologia , Feminino , Genótipo , Insuficiência Cardíaca/genética , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Knockout , Camundongos Mutantes , Miócitos Cardíacos/metabolismo , Fenótipo , Fosforilação , Gravidez , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Proc Natl Acad Sci U S A ; 106(10): 3994-9, 2009 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-19234123

RESUMO

Heterozygous loss-of-function mutations in the alpha subunit of the type I voltage-gated sodium channel Na(V)1.1 cause severe myoclonic epilepsy in infancy (SMEI), an infantile-onset epileptic encephalopathy characterized by normal development followed by treatment-refractory febrile and afebrile seizures and psychomotor decline. Mice with SMEI (mSMEI), created by heterozygous deletion of Na(V)1.1 channels, develop seizures and ataxia. Here we investigated the temperature and age dependence of seizures and interictal epileptiform spike-and-wave activity in mSMEI. Combined video-EEG monitoring demonstrated that mSMEI had seizures induced by elevated body core temperature but wild-type mice were unaffected. In the 3 age groups tested, no postnatal day (P)17-18 mSMEI had temperature-induced seizures, but nearly all P20-22 and P30-46 mSMEI had myoclonic seizures followed by generalized seizures caused by elevated core body temperature. Spontaneous seizures were only observed in mice older than P32, suggesting that mSMEI become susceptible to temperature-induced seizures before spontaneous seizures. Interictal spike activity was seen at normal body temperature in most P30-46 mSMEI but not in P20-22 or P17-18 mSMEI, indicating that interictal epileptic activity correlates with seizure susceptibility. Most P20-22 mSMEI had interictal spike activity with elevated body temperature. Our results define a critical developmental transition for susceptibility to seizures in SMEI, demonstrate that body temperature elevation alone is sufficient to induce seizures, and reveal a close correspondence between human and mouse SMEI in the striking temperature and age dependence of seizure frequency and severity and in the temperature dependence and frequency of interictal epileptiform spike activity.


Assuntos
Envelhecimento/patologia , Epilepsias Mioclônicas/complicações , Convulsões/complicações , Temperatura , Animais , Modelos Animais de Doenças , Suscetibilidade a Doenças , Eletroencefalografia , Camundongos
20.
Am J Pharm Educ ; 86(2): ajpe8538, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34301545

RESUMO

Objective. To assess the effects of a transitions of care simulation on the empathy of pharmacy students.Methods. Pharmacy students volunteered to complete a four-hour transitions of care simulation. Students were "discharged" from a simulation hospital by trained actors posing as health care providers and provided with a discharge packet, prescriptions, bus route, and bus pass. Students navigated public transportation to obtain discharge medications at a community pharmacy and then returned "home" to debrief with study investigators. Demographics were analyzed using descriptive statistics. The Kiersma-Chen Empathy Scale (KCES) was administered pre- and post-simulation, along with open-ended questions.Results. Median composite empathy scores on the KCES increased significantly from 92 to 98 following completion of the simulation. Significant increases were seen on four of the 15 questionnaire items on which themes largely involved taking patients' feelings into account when making therapeutic decisions. These four items were: "I will not allow myself to be influenced by someone's feelings when determining the best treatment," "I have difficulty identifying with someone else's feelings," "It is necessary for a health care practitioner to be able to view the world from another person's perspective," and "A health care practitioner should not be influenced by someone's feelings when determining the best treatment."Conclusion. Results of this pilot study demonstrated a significant increase in pharmacy students' overall empathy. Replicating this experiment on a larger scale may provide further insight regarding the impact of participating in simulations on transitions of care on pharmacy students' empathy.


Assuntos
Educação em Farmácia , Estudantes de Farmácia , Atitude do Pessoal de Saúde , Educação em Farmácia/métodos , Empatia , Humanos , Projetos Piloto
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa