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1.
JAMA Neurol ; 80(11): 1182-1190, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721738

RESUMO

Importance: The benefit of endovascular stroke therapy (EVT) in large vessel occlusion (LVO) ischemic stroke is highly time dependent. Process improvements to accelerate in-hospital workflows are critical. Objective: To determine whether automated computed tomography (CT) angiogram interpretation coupled with secure group messaging can improve in-hospital EVT workflows. Design, Setting, and Participants: This cluster randomized stepped-wedge clinical trial took place from January 1, 2021, through February 27, 2022, at 4 comprehensive stroke centers (CSCs) in the greater Houston, Texas, area. All 443 participants with LVO stroke who presented through the emergency department were treated with EVT at the 4 CSCs. Exclusion criteria included patients presenting as transfers from an outside hospital (n = 158), in-hospital stroke (n = 39), and patients treated with EVT through randomization in a large core clinical trial (n = 3). Intervention: Artificial intelligence (AI)-enabled automated LVO detection from CT angiogram coupled with secure messaging was activated at the 4 CSCs in a random-stepped fashion. Once activated, clinicians and radiologists received real-time alerts to their mobile phones notifying them of possible LVO within minutes of CT imaging completion. Main Outcomes and Measures: Primary outcome was the effect of AI-enabled LVO detection on door-to-groin (DTG) time and was measured using a mixed-effects linear regression model, which included a random effect for cluster (CSC) and a fixed effect for exposure status (pre-AI vs post-AI). Secondary outcomes included time from hospital arrival to intravenous tissue plasminogen activator (IV tPA) bolus in eligible patients, time from initiation of CT scan to start of EVT, and hospital length of stay. In exploratory analysis, the study team evaluated the impact of AI implementation on 90-day modified Rankin Scale disability outcomes. Results: Among 243 patients who met inclusion criteria, 140 were treated during the unexposed period and 103 during the exposed period. Median age for the complete cohort was 70 (IQR, 58-79) years and 122 were female (50%). Median National Institutes of Health Stroke Scale score at presentation was 17 (IQR, 11-22) and the median DTG preexposure was 100 (IQR, 81-116) minutes. In mixed-effects linear regression, implementation of the AI algorithm was associated with a reduction in DTG time by 11.2 minutes (95% CI, -18.22 to -4.2). Time from CT scan initiation to EVT start fell by 9.8 minutes (95% CI, -16.9 to -2.6). There were no differences in IV tPA treatment times nor hospital length of stay. In multivariable logistic regression adjusted for age, National Institutes of Health Stroke scale score, and the Alberta Stroke Program Early CT Score, there was no difference in likelihood of functional independence (modified Rankin Scale score, 0-2; odds ratio, 1.3; 95% CI, 0.42-4.0). Conclusions and Relevance: Automated LVO detection coupled with secure mobile phone application-based communication improved in-hospital acute ischemic stroke workflows. Software implementation was associated with clinically meaningful reductions in EVT treatment times. Trial Registration: ClinicalTrials.gov Identifier: NCT05838456.


Assuntos
Arteriopatias Oclusivas , Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Ativador de Plasminogênio Tecidual/uso terapêutico , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Inteligência Artificial , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , Procedimentos Endovasculares/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Arteriopatias Oclusivas/tratamento farmacológico , Software , Resultado do Tratamento
2.
Marit Stud ; 22(2): 20, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152105

RESUMO

Following pro-market policies, the Peruvian state has aimed to regulate profitable fisheries and aquaculture activities in order to increase their production. However, informal and illegal activities not only persist but are also interlinked with formal practices and frameworks, creating intertwined realities in fostering processes of institutional hybridization. This article analyses the (re)production of informal and illegal activities by explaining the formation of hybrid institutional entanglements in the Peruvian anchoveta (Engraulis ringens) fishery in Pisco and the Peruvian bay scallop (Argopecten purpuratus) aquaculture industry in Sechura. It argues that state policies to promote industrial fisheries and entrepreneurial aquaculture for the global market coupled with limited interest in supporting small-scale fisheries and aquaculture activities have resulted in processes of institutional hybridization. Within these processes, social actors resist and accommodate formal regulatory frameworks to suit their respective needs, while intertwining formal and informal practices and institutional arrangements, based on their political leverage or ability to produce hybrid institutional entanglements in a context where regulation is limited and state authority is negotiated. Under these forms of hybrid governance, the article shows that interactions between state and non-state actors do not lead to collaborations for solving problems but to the persistence of sustainability problems.

3.
Dev Biol ; 292(2): 277-289, 2006 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-16680816

RESUMO

Extracellular matrix (ECM) has specific effects on cell behavior that influence many aspects of early development. In the early postimplantation mouse embryo the ECM component laminin promotes polarization and survival of the embryonic ectoderm and formation of Reichert's membrane. In addition, dynamic patterns of laminins 1 and 10/11 expression in the embryo and the uterus correlate with the progression of implantation. In the implanting blastocyst, laminin 1 is strongly expressed in the trophectoderm basement membrane, whereas laminin 10/11 is expressed only in the inner cell mass and polar trophectoderm. In the uterus, laminin 10/11 is strongly expressed in the decidualizing matrix of the stroma. We show here that laminins 1 and 10/11 have distinct effects on trophoblast cell behavior that influence the process of implantation. Laminin 1 promotes random migration and decreases spreading, whereas laminin 10/11 promotes both spreading and persistent migration. When presented as adjacent substrates, cells stop at the boundary and do not enter the region containing laminin 1. Laminin 1 also affects cell-cell adhesion through changes in the localization of vascular endothelial (VE) cadherin. Cultured cells and primary trophoblast explants become single cells or very small groups on laminin 1 and VE-cadherin localization at regions of cell-cell contact decreases dramatically. In contrast, trophoblast cells maintain strong cell-cell contacts on substrates of laminins 10/11, and exhibit strong staining of VE-cadherin in all regions of cell-cell contact. These effects, and the localization of laminin 1 in Reichert's membrane and laminin 10/11 in the surrounding decidual matrix, suggest that these laminin isoforms influence the direction and quality of invasion of trophoblast cells during implantation, and provide epigenetic cues that drive the morphogenesis of the yolk sac placenta.


Assuntos
Laminina/metabolismo , Trofoblastos/metabolismo , Animais , Antígenos CD , Western Blotting , Caderinas/metabolismo , Adesão Celular , Linhagem Celular , Movimento Celular , Implantação do Embrião , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Feminino , Imunofluorescência , Genes Reporter , Humanos , Hibridização In Situ , Laminina/genética , Luciferases/metabolismo , Camundongos , Microscopia de Vídeo , Modelos Biológicos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Ratos , Especificidade por Substrato , Trofoblastos/citologia
4.
J Biol Chem ; 278(42): 40521-6, 2003 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-12878592

RESUMO

Conversion of glutamate 1-semialdehyde to the tetrapyrrole precursor, 5-aminolevulinate, takes place in an aminomutase-catalyzed reaction involving transformations at both the non-chiral C5 and the chiral C4 of the intermediate 4,5-diaminovalerate. Presented with racemic diaminovalerate and an excess of succinic semialdehyde, the enzyme catalyzes a transamination in which only the l-enantiomer is consumed. Simultaneously, equimolar 4-aminobutyrate and aminolevulinate are formed. The enzyme is also shown to transaminate aminolevulinate and 4-aminohexenoate to l-diaminovalerate as the exclusive amino product. The interaction of the enzyme with pure d- and l-enantiomers of diaminovalerate prepared by these reactions is described. Transamination of l-diaminovalerate yielded aminolevulinate quantitatively showing that reaction at the C5 amine does not occur significantly. A much slower transamination reaction was catalyzed with d-diaminovalerate as substrate. One product of this reaction, 4-aminobutyrate, was formed in the amount equal to that of the diaminovalerate consumed. Glutamate semialdehyde was deduced to be the other primary product and was also measured in significant amounts when a high concentration of the enzyme in its pyridoxal form was reacted with d-diaminovalerate in a single turnover. Single turnover reactions showed that both enantiomers of diaminovalerate converted the enzyme from its 420-nm absorbing pyridoxaldimine form to the 330-nm absorbing pyridoxamine via rapidly formed intermediates with different absorption spectra. The intermediate formed with l-DAVA (lambdamax = 420 nm) was deduced to be the protonated external aldimine with the 4-amino group. The intermediate formed with d-DAVA (lambdamax = 390 nm) was deduced to be the unprotonated external aldimine with the 5-amino group.


Assuntos
Diamino Aminoácidos/química , Transferases Intramoleculares/química , Aldeídos/química , Ácido Aminolevulínico/química , Caproatos/química , Ácido Glutâmico/química , Transferases Intramoleculares/metabolismo , Cinética , Modelos Químicos , Estereoisomerismo , Fatores de Tempo , Ácido gama-Aminobutírico/química
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