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1.
Nature ; 630(8015): 181-188, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38778098

RESUMO

Digital pathology poses unique computational challenges, as a standard gigapixel slide may comprise tens of thousands of image tiles1-3. Prior models have often resorted to subsampling a small portion of tiles for each slide, thus missing the important slide-level context4. Here we present Prov-GigaPath, a whole-slide pathology foundation model pretrained on 1.3 billion 256 × 256 pathology image tiles in 171,189 whole slides from Providence, a large US health network comprising 28 cancer centres. The slides originated from more than 30,000 patients covering 31 major tissue types. To pretrain Prov-GigaPath, we propose GigaPath, a novel vision transformer architecture for pretraining gigapixel pathology slides. To scale GigaPath for slide-level learning with tens of thousands of image tiles, GigaPath adapts the newly developed LongNet5 method to digital pathology. To evaluate Prov-GigaPath, we construct a digital pathology benchmark comprising 9 cancer subtyping tasks and 17 pathomics tasks, using both Providence and TCGA data6. With large-scale pretraining and ultra-large-context modelling, Prov-GigaPath attains state-of-the-art performance on 25 out of 26 tasks, with significant improvement over the second-best method on 18 tasks. We further demonstrate the potential of Prov-GigaPath on vision-language pretraining for pathology7,8 by incorporating the pathology reports. In sum, Prov-GigaPath is an open-weight foundation model that achieves state-of-the-art performance on various digital pathology tasks, demonstrating the importance of real-world data and whole-slide modelling.


Assuntos
Conjuntos de Dados como Assunto , Processamento de Imagem Assistida por Computador , Aprendizado de Máquina , Patologia Clínica , Humanos , Benchmarking , Processamento de Imagem Assistida por Computador/métodos , Neoplasias/classificação , Neoplasias/diagnóstico , Neoplasias/patologia , Patologia Clínica/métodos , Masculino , Feminino
2.
Int J Mol Sci ; 25(13)2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39000349

RESUMO

Lipid emulsions are used as adjuvant drugs to alleviate intractable cardiovascular collapse induced by drug toxicity. We aimed to examine the effect of lipid emulsions on labetalol-induced vasodilation and the underlying mechanism in the isolated rat aorta. We studied the effects of endothelial denudation, NW-nitro-l-arginine methyl ester (l-NAME), calmidazolium, methylene blue, 1H-[1,2,4]oxadiazolo[4,3-a] quinoxalin-1-one (ODQ), and lipid emulsions on labetalol-induced vasodilation. We also evaluated the effects of lipid emulsions on cyclic guanosine monophosphate (cGMP) formation, endothelial nitric oxide synthase (eNOS) phosphorylation, and endothelial calcium levels induced by labetalol. Labetalol-induced vasodilation was higher in endothelium-intact aortas than that in endothelium-denuded aortas. l-NAME, calmidazolium, methylene blue, and ODQ inhibited labetalol-induced vasodilation in endothelium-intact aortas. Lipid emulsions inhibited labetalol-induced vasodilation in endothelium-intact and endothelium-denuded aortas. l-NAME, ODQ, and lipid emulsions inhibited labetalol-induced cGMP formation in endothelium-intact aortas. Lipid emulsions reversed the stimulatory and inhibitory eNOS (Ser1177 and Thr495) phosphorylation induced by labetalol in human umbilical vein endothelial cells and inhibited the labetalol-induced endothelial calcium increase. Moreover, it decreased labetalol concentration. These results suggest that lipid emulsions inhibit vasodilation induced by toxic doses of labetalol, which is mediated by the inhibition of endothelial nitric oxide release and reduction of labetalol concentration.


Assuntos
Aorta , GMP Cíclico , Emulsões , Labetalol , Óxido Nítrico Sintase Tipo III , Vasodilatação , Animais , Vasodilatação/efeitos dos fármacos , Ratos , Aorta/efeitos dos fármacos , Aorta/metabolismo , Labetalol/farmacologia , Masculino , Óxido Nítrico Sintase Tipo III/metabolismo , GMP Cíclico/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Ratos Sprague-Dawley , Humanos , Lipídeos , Fosforilação/efeitos dos fármacos , Cálcio/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo
3.
Int J Mol Sci ; 25(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38474263

RESUMO

Dexmedetomidine is widely used to induce sedation in the perioperative period. This study examined the effect of hypothermia (33 and 25 °C) on dexmedetomidine-induced contraction in an endothelium-intact aorta with or without the nitric oxide synthase inhibitor NW-nitro-L-arginine methyl ester (L-NAME). In addition, the effect of hypothermia on the contraction induced by dexmedetomidine in an endothelium-denuded aorta with or without a calcium-free Krebs solution was examined. The effects of hypothermia on the protein kinase C (PKC), myosin light chain (MLC20) phosphorylation, and Rho-kinase membrane translocation induced by dexmedetomidine were examined. Hypothermia inhibited dexmedetomidine-induced contraction in the endothelium-intact aorta with L-NAME or endothelium-denuded aorta. Hypothermia had almost no effect on the dexmedetomidine-induced contraction in the endothelium-denuded aorta with the calcium-free Krebs solution; however, the subsequent contraction induced by the addition of calcium was inhibited by hypothermia. Conversely, the transition from profound hypothermia back to normothermia reversed the hypothermia-induced inhibition of subsequent calcium-induced contractions. Hypothermia inhibited any contraction induced by KCl, PDBu, and NaF, as well as PKC and MLC20 phosphorylation and Rho-kinase membrane translocation induced by dexmedetomidine. These results suggest that hypothermia inhibits dexmedetomidine-induced contraction, which is mediated mainly by the impediment of calcium influx and partially by the attenuation of pathways involving PKC and Rho-kinase activation.


Assuntos
Dexmedetomidina , Hipotermia , Ratos , Animais , Dexmedetomidina/farmacologia , Quinases Associadas a rho/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Cálcio/metabolismo , Hipotermia/metabolismo , Proteína Quinase C/metabolismo , Endotélio Vascular/metabolismo , Contração Muscular
4.
Gen Physiol Biophys ; 42(6): 469-478, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37855238

RESUMO

This study aimed to examine the endothelial dependence of vasodilation induced by the phosphodiesterase inhibitor theophylline in isolated rat thoracic aortas and elucidate the underlying mechanism, with emphasis on endothelial nitric oxide (NO). The effects of various inhibitors and endothelial denudation on theophylline-induced vasodilation, and the effect of theophylline on vasodilation induced by NO donor sodium nitroprusside, cyclic guanosine monophosphate (cGMP) analog bromo-cGMP, and ß-agonist isoproterenol in endothelium-denuded aorta were examined. The effects of theophylline and sodium nitroprusside on cGMP formation were also examined. We examined the effect of theophylline on endothelial nitric oxide synthase (eNOS) phosphorylation and intracellular calcium levels. Theophylline-induced vasodilation was greater in endothelium-intact aortas than that in endothelium-denuded aortas. The NOS inhibitor, NW-nitro-L-arginine methyl ester; non-specific guanylate cyclase (GC) inhibitor, methylene blue; and NO-sensitive GC inhibitor, 1H-[1,2,4]oxadiazolo[4,3-a] quinoxalin-1-one inhibited theophylline-induced vasodilation in endothelium-intact aortas. Theophylline increased the vasodilation induced by sodium nitroprusside, bromo-cGMP, and isoproterenol. Theophylline increased cGMP formation in endothelium-intact aortas, and sodium nitroprusside-induced cGMP formation in endothelium-denuded aortas. Moreover, theophylline increased stimulatory eNOS (Ser1177) phosphorylation and endothelial calcium levels, but decreased the phosphorylation of inhibitory eNOS (Thr495). These results suggested that theophylline-induced endothelium-dependent vasodilation was mediated by increased endothelial NO release and phosphodiesterase inhibition.


Assuntos
Óxido Nítrico , Vasodilatação , Ratos , Animais , Teofilina/farmacologia , Isoproterenol/farmacologia , Nitroprussiato/farmacologia , Diester Fosfórico Hidrolases/farmacologia , Cálcio , Aorta Torácica , Aorta , Óxido Nítrico Sintase Tipo III , GMP Cíclico/farmacologia , GMP Cíclico/fisiologia , Endotélio Vascular
5.
Medicina (Kaunas) ; 58(3)2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-35334625

RESUMO

A 48-year-old female patient underwent a heart transplantation for acute fulminant myocarditis, following heterologous vaccination with the ChAdOx1 nCoV-19 and Pfizer-BioNTech COVID-19. She had no history of severe acute respiratory syndrome coronavirus-2 infection. She did not exhibit clinical signs or have laboratory findings of concomitant infection before or after vaccination. Heart transplantation was performed because her heart failed to recover with venoarterial extracorporeal oxygenation support. Organ autopsy revealed giant cell myocarditis, possibly related to the vaccines. Clinicians may have to consider the possibility of the development of giant cell myocarditis, especially in patients with rapidly deteriorating cardiac function and myocarditis symptoms after COVID-19 vaccination.


Assuntos
COVID-19 , Miocardite , Vacinas contra COVID-19/efeitos adversos , ChAdOx1 nCoV-19 , Feminino , Células Gigantes , Humanos , Pessoa de Meia-Idade , Miocardite/etiologia , Vacinação/efeitos adversos
6.
Am J Pathol ; 184(3): 800-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24405768

RESUMO

McLeod neuroacanthocytosis syndrome (MLS) is a rare X-linked multisystem disease caused by XK gene mutations and characterized by hematological and neurological abnormalities. XK, a putative membrane transporter, is expressed ubiquitously and is covalently linked to Kell, an endothelin-3-converting enzyme (ECE-3). Absence of XK results in reduction of Kell at sites where both proteins are coexpressed. To elucidate the functional roles of XK, Kell, and the XK-Kell complex associated with pathogenesis in MLS, we studied the pathology of the spinal cord, anterior roots, sciatic nerve, and skeletal muscle from knockout mouse models, using Kel(-/-), Xk(-/-), Kel(-/-)Xk(-/-), and wild-type mice aged 6 to 18 months. A striking finding was that giant axons were frequently associated with paranodal demyelination. The pathology suggests probable anterograde progression from the spinal cord to the sciatic nerve. The neuropathological abnormalities were found in all three genotypes, but were more marked in the double-knockout Kel(-/-)Xk(-/-) mice than in either Kel(-/-) or Xk(-/-) mice. Skeletal muscles from Xk(-/-) and Kel(-/-)Xk(-/-) mice showed mild abnormalities, but those from Kel(-/-) mice were similar to the wild type. The more marked neuropathological abnormalities in Kel(-/-)Xk(-/-) mice suggest a possible functional association between XK and Kell in nonerythroid tissues.


Assuntos
Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Axônios/patologia , Glicoproteínas de Membrana/metabolismo , Metaloendopeptidases/metabolismo , Neuroacantocitose/patologia , Sistemas de Transporte de Aminoácidos Neutros/genética , Animais , Ácido Aspártico Endopeptidases/genética , Axônios/metabolismo , Modelos Animais de Doenças , Enzimas Conversoras de Endotelina , Feminino , Genótipo , Humanos , Masculino , Glicoproteínas de Membrana/genética , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Metaloendopeptidases/genética , Camundongos , Camundongos Knockout , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Neuroacantocitose/genética
7.
J Adv Nurs ; 71(10): 2258-67, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26010379

RESUMO

AIM: To report an analysis of the concept of 'meaning in work'. BACKGROUND: Associated with initiatives to improve the quality of working life and the emerging movement of positive organizations, 'meaning in work' has been studied as a positive individual-level state. 'Meaning in work' has potential benefits that will improve the nursing workforce if this concept is embraced in nursing. However, the concept is not clearly defined because it has been approached from diverse theoretical perspectives and used interchangeably with analogous terms. DESIGN: A concept analysis. DATA SOURCES: Three key terms (using 'work', 'meaning' or 'meaningful', 'meaning of work', 'logotherapy') were searched in the CINAHL, PsycINFO, Business Source Complete and ABI/INFORM Global online databases from January 1940-March 2015. Among 346 articles retrieved, 28 studies were included for this concept analysis. METHODS: The procedure of concept analysis developed by Walker and Avant (2011) was used. RESULTS: Four critical attributes are identified: (1) experienced positive emotion at work; (2) meaning from work itself; (3) meaningful purpose and goals of work; and (4) work as a part of life that contributes towards meaningful existence. The identified antecedent of 'meaning in work' was a cognitive shift and the identified consequences were positive personal experience and positive impact on peers and organizations. CONCLUSION: This article provides a clear definition of 'meaning in work'. The resulting coherent definition will facilitate the use of 'meaning in work' in nursing research.


Assuntos
Enfermagem , Trabalho/psicologia , Emoções , Humanos , Satisfação no Emprego , Modelos Psicológicos , Motivação , Enfermeiras e Enfermeiros/psicologia , Prática Profissional
8.
J Clin Nurs ; 23(11-12): 1486-501, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24028657

RESUMO

AIMS AND OBJECTIVES: To review current research evidence on the outcomes of mobilising hospitalised adults. BACKGROUND: Although immobility is known to cause functional decline or complications, inpatient ambulation emerged as the most often missed element of nursing care. This study is designed to review research studies that give evidence as to the consequences of mobilising or not mobilising hospitalised adult patients. DESIGN: A literature review of published peer-reviewed empirical research was undertaken. METHODS: The electronic databases of MEDLINE (Ovid), CINAHL, and PubMed were accessed to search for relevant empirical articles, supplemented by a search of reference lists contained in retrieved articles and citation tracking. RESULTS: Thirty-six studies were identified for inclusion in the review. Four areas (study design, sample size, measurement and statistical analysis) were evaluated for methodological quality, and most studies showed strong quality. A synthesis of the findings generated four themes of the effects of inpatient mobilisation: (1) physical outcomes included pain, deep vein thrombosis, fatigue, etc.; (2) psychological outcomes included anxiety, depressive mood, distress, comfort and satisfaction; (3) social outcomes included quality of life and independence; and (4) organisational outcomes included length of stay, mortality and cost. CONCLUSION: Mobilising hospitalised adults brings benefits for not only physical functioning, but also their emotional and social well-being. Moreover, ambulation yields important organisational benefits. These benefits of mobilisation on four areas required viewing the patient in a holistic manner. Even though each study approached different types of patients, illnesses and procedures, this review showed that most inpatients would benefit from mobilisation and would experience optimal functions. RELEVANCE TO CLINICAL PRACTICE: The importance of mobilisation for positive patient outcomes highlights the need to develop methods to ensure that this nursing action is completed on a systematic basis.


Assuntos
Deambulação Precoce , Pacientes Internados , Complicações Pós-Operatórias/prevenção & controle , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/enfermagem , Procedimentos Cirúrgicos Operatórios/efeitos adversos
9.
Blood Cells Mol Dis ; 50(2): 80-5, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23122227

RESUMO

XK is a putative transporter of unknown function that is ubiquitously expressed and linked through disulfide bonds to Kell protein, an endothelin-3 (ET-3)-converting enzyme. We generated three knockout (KO) mice that lacked either Xk, Kell or both proteins and characterized erythrocyte cation levels, transport and hematological parameters. Absence of Xk or Kell was accompanied by changes in erythrocyte K(+), Mg(2+), Na(+) and Ca(2+) transport that were associated with changes in mean cellular volume and corpuscular hemoglobin concentration mean. Baseline Ca(2+)-ATPase activity was undetected in erythrocytes from all three mouse types but was restored upon pre-incubation with ET-3. Consistent with these alterations in Ca(2+) handling, we observed increased Gardos channel activity in Kel and Xk KO mice. In addition Kel deletion was associated with increased Mg(2+) permeability while Xk deletion blocked Na/Mg exchanger activity. Our results provide evidence that cellular divalent cation regulation is functionally coupled to the Kell/XK system in erythrocytes and loss of this complex may contribute to acanthocytosis formation in McLeod syndrome.


Assuntos
Sistemas de Transporte de Aminoácidos Neutros/fisiologia , Cátions Bivalentes/sangue , Eritrócitos/metabolismo , Sistema do Grupo Sanguíneo de Kell/fisiologia , Abetalipoproteinemia/sangue , Abetalipoproteinemia/genética , Acantócitos , Sistemas de Transporte de Aminoácidos Neutros/sangue , Sistemas de Transporte de Aminoácidos Neutros/deficiência , Sistemas de Transporte de Aminoácidos Neutros/genética , Animais , Antiporters/sangue , Cálcio/sangue , ATPases Transportadoras de Cálcio/sangue , Endotelina-3/farmacologia , Volume de Eritrócitos , Doenças Genéticas Ligadas ao Cromossomo X/sangue , Doenças Genéticas Ligadas ao Cromossomo X/genética , Hemólise/genética , Homeostase , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/sangue , Transporte de Íons , Sistema do Grupo Sanguíneo de Kell/genética , Magnésio/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Complexos Multiproteicos , Neuroacantocitose , Potássio/sangue , Receptores de Endotelina/sangue , Sódio/sangue
10.
Transfusion ; 53(11 Suppl 2): 2872-81, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23560718

RESUMO

BACKGROUND: The numerous antigens in the Kell blood group system result from missense nucleotide changes in KEL. Antibodies to antigens in this system can be clinically important. We describe six probands whose plasma contained antibodies to high-prevalence Kell antigens and discuss their relationship. STUDY DESIGN AND METHODS: Polymerase chain reaction amplification, direct sequencing, restriction fragment length polymorphism assays, hemagglutination, flow cytometry, and protein modeling were performed by standard methods. RESULTS: Proband 1 (KUCI) and her serologically compatible sister were heterozygous for a nucleotide change in Exon 11 (KEL*1271C/T; Ala424Val). Proband 2 (KANT) was heterozygous for KEL*1283G/T (Arg428Leu) and KEL*1216C/T (Arg406Stop) in Exon 11. Red blood cells (RBCs) from Proband 1 and her sister were not agglutinated by plasma from Proband 2; however, RBCs from Proband 2 were agglutinated by plasma from Proband 1. Probands 3, 4, 5, and 6 had the KEL*1391C>T change associated with the previously reported KETI- phenotype. Proband 5 was also homozygous for KEL*905T>C encoding the K11-K17+ phenotype. Hemagglutination studies revealed an association between KUCI, KANT, KETI, and K11. Protein modeling indicated that whereas Ala424 and Arg428 are clustered, Val302 and Thr464 are not. CONCLUSION: Ala424 in the Kell glycoprotein is associated with the high-prevalence Kell antigen, KUCI (ISBT 006032), which is detected by the antibody of Proband 1. Arg428 is associated with the high-prevalence Kell antigen, KANT (ISBT 006033). The association between KUCI, KANT, KETI, and K11 and the results of protein modeling are discussed.


Assuntos
Eritrócitos/imunologia , Sistema do Grupo Sanguíneo de Kell/genética , Sistema do Grupo Sanguíneo de Kell/imunologia , Adulto , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Linhagem , Testes Sorológicos , Distribuição Tecidual , Reação Transfusional
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