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1.
Front Neurosci ; 16: 952355, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466162

RESUMO

Objective: Term congenital heart disease (CHD) neonates display abnormalities of brain structure and maturation, which are possibly related to underlying patient factors, abnormal physiology and perioperative insults. Our primary goal was to delineate associations between clinical factors and postnatal brain microstructure in term CHD neonates using diffusion tensor imaging (DTI) magnetic resonance (MR) acquisition combined with complementary data-driven connectome and seed-based tractography quantitative analyses. Our secondary goal was to delineate associations between mild dysplastic structural brain abnormalities and connectome and seed-base tractography quantitative analyses. These mild dysplastic structural abnormalities have been derived from prior human infant CHD MR studies and neonatal mouse models of CHD that were collectively used to calculate to calculate a brain dysplasia score (BDS) that included assessment of subcortical structures including the olfactory bulb, the cerebellum and the hippocampus. Methods: Neonates undergoing cardiac surgery for CHD were prospectively recruited from two large centers. Both pre- and postoperative MR brain scans were obtained. DTI in 42 directions was segmented into 90 regions using a neonatal brain template and three weighted methods. Clinical data collection included 18 patient-specific and 9 preoperative variables associated with preoperative scan and 6 intraoperative (e.g., cardiopulmonary bypass and deep hypothermic circulatory arrest times) and 12 postoperative variables associated with postoperative scan. We compared patient specific and preoperative clinical factors to network topology and tractography alterations on a preoperative neonatal brain MRI, and intra and postoperative clinical factors to network topology alterations on postoperative neonatal brain MRI. A composite BDS was created to score abnormal findings involving the cerebellar hemispheres and vermis, supratentorial extra-axial fluid, olfactory bulbs and sulci, hippocampus, choroid plexus, corpus callosum, and brainstem. The neuroimaging outcomes of this study included (1) connectome metrics: cost (number of connections) and global/nodal efficiency (network integration); (2) seed based tractography methods of fractional anisotropy (FA), radial diffusivity, and axial diffusivity. Statistics consisted of multiple regression with false discovery rate correction (FDR) comparing the clinical risk factors and BDS (including subcortical components) as predictors/exposures and the global connectome metrics, nodal efficiency, and seed based- tractography (FA, radial diffusivity, and axial diffusivity) as neuroimaging outcome measures. Results: A total of 133 term neonates with complex CHD were prospectively enrolled and 110 had analyzable DTI. Multiple patient-specific factors including d-transposition of the great arteries (d-TGA) physiology and severity of impairment of fetal cerebral substrate delivery (i.e., how much the CHD lesion alters typical fetal circulation such that the highest oxygen and nutrient rich blood from the placenta are not directed toward the fetal brain) were predictive of preoperative reduced cost (p < 0.0073) and reduced global/nodal efficiency (p < 0.03). Cardiopulmonary bypass time predicted postoperative reduced cost (p < 0.04) and multiple postoperative factors [extracorporeal membrane oxygenation (ECMO), seizures and cardiopulmonary resuscitation (CPR)] were predictive of postoperative reduced cost and reduced global/nodal efficiency (p < 0.05). Anthropometric measurements (weight, length, and head size) predicted tractography outcomes. Total BDS was not predictive of brain network topology. However, key subcortical components of the BDS score did predict key global and nodal network topology: abnormalities of the cerebellum predicted reduced cost (p < 0.0417) and of the hippocampus predicted reduced global efficiency (p < 0.0126). All three subcortical structures predicted unique alterations of nodal efficiency (p < 0.05), including hippocampal abnormalities predicting widespread reduced nodal efficiency in all lobes of the brain, cerebellar abnormalities predicting increased prefrontal nodal efficiency, and olfactory bulb abnormalities predicting posterior parietal-occipital nodal efficiency. Conclusion: Patient-specific (d-TGA anatomy, preoperative impairment of fetal cerebral substrate delivery) and postoperative (e.g., seizures, need for ECMO, or CPR) clinical factors were most predictive of diffuse postnatal microstructural dysmaturation in term CHD neonates. Anthropometric measurements (weight, length, and head size) predicted tractography outcomes. In contrast, subcortical components (cerebellum, hippocampus, olfactory) of a structurally based BDS (derived from CHD mouse mutants), predicted more localized and regional postnatal microstructural differences. Collectively, these findings suggest that brain DTI connectome and seed-based tractography are complementary techniques which may facilitate deciphering the mechanistic relative contribution of clinical and genetic risk factors related to poor neurodevelopmental outcomes in CHD.

2.
Cancer ; 128(2): 311-316, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34614198

RESUMO

BACKGROUND: Over the past 2 decades there has been a substantial increase in the number of new cancer medicines; this has been accompanied by a dramatic rise in drug costs. It is unknown how these trends impact the revenue of the pharmaceutical sector. METHODS: Retrospective cohort study to characterize temporal trends of revenue generated from cancer medicines as a proportion of total drug revenue among 10 large pharmaceutical companies from 2010 to 2019. Itemized product-sales data publicly available through company websites or annual filings were used to identify annual drug revenue. Revenue data were adjusted for inflation and converted to 2019 US dollars. RESULTS: During the study period, cumulative annual revenue generated from cancer drugs increased by 70%: from $55.8 billion to $95.1 billion, while cumulative revenue from nononcology drugs decreased 18%: from $342.2 billion to $281.5 billion. The proportion of total drug revenue generated from oncology drugs increased substantially over the study period: from 14% in 2010 to 25% in 2019 (τ = 1.0, P < .001). CONCLUSIONS: Among 10 of the world's largest pharmaceutical companies, revenues generated from the sale of cancer drugs have increased by 70% over the past decade, while revenues from other medicines have decreased by 18%. Revenues from cancer drugs now account for one-quarter of the net revenues from these companies. Further work is needed to understand if this increase in sales revenue reflects industry profit, and to what extent increased spending has translated into improvements in patient and population outcomes.


Assuntos
Custos de Medicamentos , Indústria Farmacêutica , Preparações Farmacêuticas , Estudos de Coortes , Comércio , Humanos , Estudos Retrospectivos
3.
PLoS One ; 5(11): e15461, 2010 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-21103397

RESUMO

Prospects of obtaining plants glowing in the dark have captivated the imagination of scientists and layman alike. While light emission has been developed into a useful marker of gene expression, bioluminescence in plants remained dependent on externally supplied substrate. Evolutionary conservation of the prokaryotic gene expression machinery enabled expression of the six genes of the lux operon in chloroplasts yielding plants that are capable of autonomous light emission. This work demonstrates that complex metabolic pathways of prokaryotes can be reconstructed and function in plant chloroplasts and that transplastomic plants can emit light that is visible by naked eye.


Assuntos
Proteínas de Bactérias/metabolismo , Luminescência , Nicotiana/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Cloroplastos/química , Cloroplastos/genética , Cloroplastos/metabolismo , Genoma de Cloroplastos/genética , Photobacterium/genética , Photobacterium/metabolismo , Plantas Geneticamente Modificadas , Nicotiana/química , Nicotiana/genética , Fatores de Transcrição/química , Fatores de Transcrição/genética
4.
J Vis Exp ; (42)2010 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-20834216

RESUMO

Here, we present a simple and rapid protocol to detect and assess the extent of cell-to-cell macromolecular transport in planta. In this protocol, a fluorescently tagged-protein of interest is transiently expressed in plant tissue following biolistic delivery of its encoding DNA construct. The intra- and intercellular distribution of the tagged protein is then analyzed by confocal microscopy. We describe this technology in detail, providing step-by-step protocols to assay and evaluate the extent of symplastic protein transport in three plant species, Arabidopsis thaliana, Nicotiana benthamiana and N. tabacum (tobacco).


Assuntos
Biolística/métodos , Comunicação Celular/fisiologia , Complexos Multiproteicos/metabolismo , Células Vegetais , Plantas/metabolismo , Arabidopsis/citologia , Arabidopsis/metabolismo , Microscopia Confocal , Nicotiana/citologia , Nicotiana/metabolismo
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