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1.
Am J Physiol Lung Cell Mol Physiol ; 317(6): L816-L822, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31596105

RESUMO

Several lines of evidence have implicated long interspersed nuclear element-1 (LINE-1) retroelement in the onset and progression of lung cancer. Retrotransposition-dependent mechanisms leading to DNA mobilization give rise to insertion mutations and DNA deletions, whereas retrotransposition-independent mechanisms disrupt epithelial programming and differentiation. Previous work by our group established that tobacco carcinogens such as benzo(a)pyrene (BaP) reactivate LINE-1 in bronchial epithelial cells through displacement of nucleosome remodeling and deacetylase (NuRD) corepressor complexes and interference with retinoblastoma-regulated epigenetic signaling. Whether LINE-1 in coordination with other genes within its regulatory network contributes to the in vivo genotoxic response to BaP remains largely unknown. Evidence is presented here that intratracheal instillation of ORFeusLSL mice with BaP alone or in combination with adenovirus (adeno)-CRE recombinase is genotoxic to the lung and associated with activation of the human LINE-1 transgene present in these mice. LINE-1 reactivation modulated the expression of genes involved in oncogenic signaling, and these responses were most pronounced in female mice compared with males and synergized by adeno-CRE recombinase. This is the first report linking LINE-1 and genes within its oncogenic regulatory network with early sexually dimorphic responses of the lung in vivo.


Assuntos
Benzo(a)pireno/toxicidade , Dano ao DNA , Redes Reguladoras de Genes , Elementos Nucleotídeos Longos e Dispersos/genética , Neoplasias Pulmonares/patologia , Pulmão/patologia , Transgenes/fisiologia , Animais , Carcinógenos/toxicidade , Reprogramação Celular , Humanos , Integrases/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/genética , Camundongos
2.
Philos Trans A Math Phys Eng Sci ; 377(2137)2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30530544

RESUMO

The dome of Santa Maria del Fiore, Florence Cathedral, was built between 1420 and 1436 by architect Filippo Brunelleschi and it is now cracking under its own weight. Engineering efforts are under way to model the dome's structure and reinforce it against further deterioration. According to some scholars, Brunelleschi might have built reinforcement structures into the dome itself; however, the only known reinforcement is a wood chain 7.75 m above the springing of the Cupola. Multiple scattering muon radiography is a non-destructive imaging method that can be used to image the interior of the dome's wall and therefore ascertain the layout and status of any iron substructure in it. A demonstration measurement was performed at the Los Alamos National Laboratory on a mock-up wall to show the feasibility of the work proposed, and a lightweight and modular imaging system is currently under construction. We will discuss here the results of the demonstration measurement and the potential of the proposed technique, describe the imaging system under construction and outline the plans for the measurement.This article is part of the Theo Murphy meeting issue 'Cosmic-ray muography'.

3.
J Phys Chem A ; 121(1): 238-243, 2017 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-27997195

RESUMO

An equation of state for the energetic molecular crystal pentaerythritol tetranitrate (PETN) has been developed from a parametrized model for its Helmholtz free energy. The ion motion contribution to the free energy is represented by a sum of Debye models for the vibrational modes of mainly lattice phonon and intramolecular character. The dependence of the frequencies of the normal modes on density is captured using the quasi-harmonic approximation whereby the Debye temperatures for both populations of modes depend explicitly on specific volume. The dependence of the Debye temperatures on specific volume was parametrized to normal-mode frequencies computed from solid state dispersion-corrected density functional theory. The model provides a good description of the thermophysical properties of PETN. The equation of state has been applied to the calculation of thermodynamic states along the principal Hugoniot of single crystal PETN.

4.
Rev Esp Anestesiol Reanim (Engl Ed) ; 71(2): 112-124, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38244774

RESUMO

Septic shock is a highly lethal and prevalent disease. Progressive circulatory dysfunction leads to tissue hypoperfusion and hypoxia, eventually evolving to multiorgan dysfunction and death. Prompt resuscitation may revert these pathogenic mechanisms, restoring oxygen delivery and organ function. High heterogeneity exists among the determinants of circulatory dysfunction in septic shock, and current algorithms provide a stepwise and standardized approach to conduct resuscitation. This review provides the pathophysiological and clinical rationale behind ANDROMEDA-SHOCK-2, an ongoing multicenter randomized controlled trial that aims to compare a personalized resuscitation strategy based on clinical phenotyping and peripheral perfusion assessment, versus standard of care, in early septic shock resuscitation.


Assuntos
Choque Séptico , Humanos , Choque Séptico/terapia , Hidratação , Ressuscitação , Algoritmos , Estudos Multicêntricos como Assunto
5.
Public Health Action ; 12(4): 180-185, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36561900

RESUMO

INTRODUCTION: Chatbots have emerged as a first link to care in recent years. The COVID-19 pandemic, and consequent health system disruptions, expanded their use. Socios En Salud (SES) introduced chatbots in Peru, which experienced one of the highest excess COVID mortalities in the world. METHODS: SES and the government identified unmet population health needs, which could be amenable to virtual interventions. Chatbots were developed to screen individuals for these conditions; we describe the period of deployment, number of screenings, and number of people who received services. RESULTS: Between April 2020 and May 2021, SES deployed nine ChatBots: four for mental health, two for maternal and child health, and three for chronic diseases: breast cancer, hypertension, diabetes mellitus, and obesity. Mental health services were provided to 42,932 people, 99.99% of those offered services. The other ChatBots reached fewer people. Overall, more than 50% of eligible people accepted chatbot-based services. DISCUSSION: ChatBot use was highest for mental health. Chatbots may increase connections between a vulnerable population and health services; this is likely dependent on several factors, including condition, population, and penetration of smart phones. Future research will be critical to understand user experience and preferences and to ensure that chatbots link vulnerable populations to appropriate, high-quality care.


INTRODUCTION: Les chatbots se sont imposés comme un premier lien aux soins ces dernières années. La pandémie de COVID-19, et les perturbations du système de santé qui en ont résultées, ont élargi leur champ d'application. Socios En Salud (SES) a introduit les chatbots au Pérou, qui a connu l'une des surmortalités dues au COVID les plus élevées au monde. MÉTHODES: SES et le gouvernement ont identifié des besoins non satisfaits en matière de santé de la population, qui pourraient faire l'objet d'interventions virtuelles. Des chatbots ont été développés pour dépister des individus pour ces conditions ; nous décrivons la période de leur déploiement, le nombre de dépistages et le nombre de personnes qui ont reçu ces services. RÉSULTATS: Entre avril 2020 et mai 2021, SES a déployé neuf ChatBots : quatre pour la santé mentale, deux pour la santé maternelle et infantile et trois pour les maladies chroniques, comme le cancer du sein, l'hypertension, le diabète et l'obésité. Des services de santé mentale ont été fournis à 42 932 personnes, soit 99,99% des personnes proposées. Les autres ChatBots ont touché moins de personnes. Dans l'ensemble, plus de 50% des personnes éligibles ont accepté les services proposés par les chatbots. DISCUSSION: L'utilisation des ChatBots était la plus élevée pour la santé mentale. Les chatbots peuvent augmenter les connexions entre une population vulnérable et les services de santé, mais cela dépende de plusieurs facteurs, dont la condition, la type de population et la pénétration des smartphones. Les recherches futures seront essentielles pour comprendre l'expérience et les préférences des utilisateurs et pour s'assurer que les chatbots relient les populations vulnérables vulnérables aux soins appropriés et de qualité.

6.
Environ Pollut ; 271: 116380, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33387779

RESUMO

A vast amount of evidence indicates that bisphenol A (BPA) and phthalates are widely distributed in the environment since these compounds are mass-produced for the manufacture of plastics and plasticizers. These compounds belong to a large group of substances termed endocrine-disrupting chemicals (EDC). It is well known that humans and living organisms are unavoidably and unintentionally exposed to BPA and phthalates from food packaging materials and many other everyday products. BPA and phthalates exert their effect by interfering with hormone synthesis, bioavailability, and action, thereby altering cellular proliferation and differentiation, tissue development, and the regulation of several physiological processes. In fact, these EDC can alter fetal programming at an epigenetic level, which can be transgenerational transmitted and may be involved in the development of various chronic pathologies later in the adulthood, including metabolic, reproductive and degenerative diseases, and certain types of cancer. In this review, we describe the most recent proposed mechanisms of action of these EDC and offer a compelling selection of experimental, epidemiological and clinical studies, which show evidence of how exposure to these pollutants affects our health during development, and their association with a wide range of reproductive, metabolic and neurological diseases, as well as hormone-related cancers. We stress the importance of concern in the general population and the urgent need for the medical health care system to closely monitor EDC levels in the population due to unavoidable and involuntary exposure to these pollutants and their impact on human health.


Assuntos
Disruptores Endócrinos , Exposição Ambiental , Adulto , Compostos Benzidrílicos/toxicidade , Política de Saúde , Humanos , Fenóis/toxicidade
7.
Neurobiol Learn Mem ; 92(1): 45-52, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19249379

RESUMO

Consolidation is the process by which a new memory is stabilized over time, and is dependent on de novo protein synthesis. A useful model for studying memory formation is gustatory memory, a type of memory in which a novel taste may become either safe by not being followed by negative consequences (attenuation of neophobia, AN), or aversive by being followed by post-digestive malaise (conditioned taste aversion, CTA). Here we evaluated the effects of the administration of a protein synthesis inhibitor in the nucleus accumbens (NAc) shell for either safe or aversive taste memory trace consolidation. To test the effects on CTA and AN of protein synthesis inhibition, anisomycin (100microg/microl) was bilaterally infused into the NAc shell of Wistar rats' brains. We found that post-trial protein synthesis blockade impaired the long-term safe taste memory. However, protein synthesis inhibition failed to disrupt the long-term memory of CTA. In addition, we infused anisomycin in the NAc shell after the pre-exposure to saccharin in a latent inhibition of aversive taste. We found that the protein synthesis inhibition impaired the consolidation of safe taste memory, allowing the aversive taste memory to form and consolidate. Our results suggest that protein synthesis is required in the NAc shell for consolidation of safe but not aversive taste memories, supporting the notion that consolidation of taste memory is processed in several brain regions in parallel, and implying that inhibitory interactions between both taste memory traces do occur.


Assuntos
Anisomicina/administração & dosagem , Comportamento Alimentar/efeitos dos fármacos , Memória/efeitos dos fármacos , Núcleo Accumbens/efeitos dos fármacos , Inibidores da Síntese de Proteínas/administração & dosagem , Análise de Variância , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Cateterismo , Condicionamento Clássico/efeitos dos fármacos , Cloreto de Lítio/toxicidade , Masculino , Ratos , Ratos Wistar , Sacarina/administração & dosagem , Edulcorantes/administração & dosagem , Paladar
8.
Anal Bioanal Chem ; 395(2): 315-22, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19330320

RESUMO

The far infrared spectra of (100), (010), and (001)-oriented RDX single crystals were measured as the crystal was rotated about the axis perpendicular to the polarization plane of the incident radiation. Absorption measurements were taken at temperatures of both 20 K and 295 K for all rotations using terahertz time-domain spectroscopy. A number of discrete absorptions were found ranging from 10-100 cm(-1) (0.3-3 THz). The absorptions are highly dependent on the orientation of the terahertz polarization with respect to crystallographic axes.

9.
J Thromb Haemost ; 17(2): 383-388, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30552743

RESUMO

Essentials Current risk scores for heparin-induced thrombocytopenia (HIT) are not computer-friendly. We compared a new computerized risk score with the 4Ts score in a large healthcare system. The computerized risk score agrees with the 4Ts score 85% of the time. The new score could potentially improve HIT diagnosis via incorporation into decision support. SUMMARY: Background (HIT) is an immune-mediated adverse drug event associated with life-threatening thrombotic complications. The 4Ts score is widely used to estimate the risk for HIT and guide diagnostic testing, but it is not easily amenable to computerized clinical decision support (CDS) implementation. Objectives Our main objective was to develop an HIT computerized risk (HIT-CR) scoring system that provides platelet count surveillance for timing and degree of thrombocytopenia to identify those for whom diagnostic testing should be considered. Our secondary objective was to evaluate clinical management and subsequent outcomes in those identified as being at risk for HIT. Methods We retrospectively analyzed data from a stratified sample of 150 inpatients treated with heparin to compare the performance of the HIT-CR scoring system with that of a clinically calculated 4Ts score. We took a 4Ts score of ≥ 4 as the gold standard to determine whether HIT diagnostic testing should be performed. Results The best cutoff point of the HIT-CR score was a score of 3, which yielded 85% raw agreement with the 4Ts score and a kappa of 0.69 (95% confidence interval 0.57-0.81). Ninety per cent of patients with 4Ts score of ≥ 4 failed to undergo conventionally recommended diagnostic testing; 38% of these experienced persistent, unexplained thrombocytopenia, and 4% suffered life-threatening thrombotic complications suggestive of undiagnosed HIT. Conclusion The HIT-CR scoring system is practical for computerized CDS, agrees well with the 4Ts score, and should be prospectively evaluated for its ability to identify patients who should be tested for HIT.


Assuntos
Anticoagulantes/efeitos adversos , Plaquetas/efeitos dos fármacos , Simulação por Computador , Técnicas de Apoio para a Decisão , Heparina/efeitos adversos , Contagem de Plaquetas , Trombocitopenia/induzido quimicamente , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Registros Eletrônicos de Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Trombocitopenia/sangue , Trombocitopenia/diagnóstico , Adulto Jovem
10.
Respir Physiol Neurobiol ; 266: 156-162, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31128272

RESUMO

Mitochondria play a major role in the brain. Apart from energy production, mitochondria regulate key factors in the activation of cell signaling pathways such as survival, proliferation, and differentiation. While all these processes occur during the physiological development of the brain, it is surprising that the mitochondrial functions and functioning in the brain during the postnatal development remain poorly explored. In this work, we collected samples of brainstem and cortex of mice at postnatal ages 3 (P3), 21 (P21), and at adulthood (3 months old) and evaluated the mitochondrial oxygen consumption after complex I activation. To do so, we used our oxygraph-2 K system (OROBOROS) that measures the mitochondrial bioenergetics in saponin-permeabilized tissue punches of 2  mg weight. Furthermore, as sex dimorphism in the brain occurs since very early stages of development, we performed experiments in brain samples of male and female mice. Accordingly, the mitochondrial oxygen consumption rate (OCR) was evaluated under activation of complex I (NADH-linked respiration - mitochondrial state 3), and during the inhibition of the complex V (ATP synthase) with oligomycin (mitochondrial state 4). In following, the respiratory control ratio (RCR - state 3/state4) was calculated as an index of mitochondrial oxidative-phosphorylation coupling. Our results show that the activity of the mitochondrial complex I in the brain increases along with the postnatal development in a sex- and tissue-dependent manner, with males showing higher activity than females, and with brainstem tissue showing higher activity than cortex. Our data may contribute to a better understanding of the sex-dependent maturation of the cortex and the cardiorespiratory network located in the brainstem.


Assuntos
Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Mitocôndrias/metabolismo , NAD/metabolismo , Respiração , Caracteres Sexuais , Animais , Animais Recém-Nascidos , Tronco Encefálico/crescimento & desenvolvimento , Tronco Encefálico/metabolismo , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL
11.
Matrix Biol ; 27(5): 462-74, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18378437

RESUMO

Osteopontin is a primary cytokine and matrix-associated protein involved in medial thickening and neointima formation. Osteopontin binds integrin receptors, activates cell migration and matrix metalloproteinases, and mediates arteriosclerotic lesion formation and vessel calcification. To understand the complex biology of osteopontin, computational methodology was employed to identify sets of genes whose transcriptional states were predictive of osteopontin gene expression based on the transcriptional states of 12,400 genes and ESTs across 235 independent Affymetrix Murine Genome Array MG_U74Av2 hybridizations. Arginase [GenBank: U51805] and Mac-2 antigen [GenBank: X16834] were identified as primary attractors within the gene-gene interaction network of osteopontin. Resolution of molecular interactions among these genes indicated that the majority of predictor genes could be linked through redox regulated transcription by nuclear factor kappa-B and transforming growth factor beta inducible early gene 1 regulatory elements. Subsequent molecular analyses established redox sensitivity of a 200 bp region within the 5' UTR of opn promoter and implicated nuclear factor kappa-B and transforming growth factor beta inducible early gene 1 cis-acting elements in the regulation of osteopontin.


Assuntos
Regulação da Expressão Gênica , Redes Reguladoras de Genes , Osteopontina/genética , Algoritmos , Animais , Antioxidantes/farmacologia , Arginase/genética , Células Cultivadas , Biologia Computacional/métodos , Proteínas de Ligação a DNA/metabolismo , Etiquetas de Sequências Expressas , Galectina 3/genética , Peróxido de Hidrogênio/farmacologia , Camundongos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Mutagênese Sítio-Dirigida , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , NF-kappa B/metabolismo , Osteopontina/metabolismo , Oxirredução , Regiões Promotoras Genéticas/genética , Ratos , Elementos de Resposta/genética , Deleção de Sequência , Fatores de Transcrição/metabolismo , Transfecção , Fator de Crescimento Transformador beta1/metabolismo
13.
Mutat Res Rev Mutat Res ; 778: 51-60, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30454683

RESUMO

Long interspersed nuclear elements-1 (Line-1 or L1) accounts for approximately 17% of the human genome. The majority of L1s are inactive, but ∼100 remain retrotransposon competent (RC-L1) and able to retrotranspose through RNA intermediates to different locations of the genome. L1 is involved in both disease initiation and progression via retrotransposition dependent and independent mechanisms. Retrotransposed L1 sequences disrupt genetic loci at sites of insertion, while the activities of L1 si/piRNAs, mRNAs, and ORF1 and ORF2 proteins, and have been implicated in the etiology and progression of several human diseases. Despite these relationships, little is known about the clinical utility of L1 as a biomarker of disease initiation and progression, or the utility of small molecules to inhibit and reverse the harmful effects of L1. In this review, we discuss the life cycle of L1, somatic and germline inhibitions, the mechanisms of L1 retrotransposition dependent and independent disease initiation and progression, clinical utilities, and potential of L1s as pharmacologic targets for the treatment of cancer.


Assuntos
Genoma Humano/genética , Elementos Nucleotídeos Longos e Dispersos/genética , Terapia de Alvo Molecular , Neoplasias/genética , Endonucleases/genética , Humanos , Neoplasias/terapia , Proteínas/genética , RNA Interferente Pequeno/genética , DNA Polimerase Dirigida por RNA/genética
14.
Artigo em Inglês | MEDLINE | ID: mdl-30637114

RESUMO

BACKGROUND: An estimated 19-25% of perinatal women in low- and middle-income countries are affected by depression which, untreated, is associated with multiple health problems for mothers and children. Nonetheless, few perinatal women have access to depression care. The Thinking Healthy Programme (THP), promoted by the World Health Organization (WHO), is an evidence-based, non-specialist delivered depression intervention that addresses this care gap. However, the WHO THP manual explains intervention delivery but not the antecedents to implementation. Here, we describe a principled, planned approach leading to the implementation of THP in Lima, Peru by the non-profit organization Socios En Salud with community health workers (CHW) to inform its implementation in other settings. METHODS: The Replicating Effective Programs (REP) framework guided THP implementation, following four phases: (I) pre-conditions; (II) pre-implementation; (III) implementation; and (IV) maintenance and evolution. This paper centers on REP phases I and II, including (1) documented high perinatal depression rates in Peru; (2) designation of perinatal depression as a government priority; (3) THP Implementation Team orientation and training; (4) data collection plan development; (5) public health system coordination; (6) CHW selection and training; and (7) THP launch. RESULTS: Between December 2016 and March 2017, a THP training program was developed and seven CHW were trained to deliver the intervention to 10 perinatal women, the first of whom was enrolled on 17 April 2017. CONCLUSIONS: THP was rapidly implemented by a community-based organization with no prior experience in delivering non-specialist perinatal depression care. The steps followed may inform the implementation of THP in other settings.

15.
Food Chem ; 221: 822-828, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27979280

RESUMO

In this study, a chicken meat containing AgNPs (candidate reference material Nanolyse 14) has been used as a model matrix to study the fate and behaviour of AgNPs upon oral ingestion following an in vitro model that included saliva, gastric and intestinal digestions. The behaviour of a 40nm AgNPs standard solution during the three digestion steps was also evaluated. Sample preparation conditions were optimised to prevent AgNPs oxidation and/or aggregation and to ensure the representativeness of the reported results. Total silver released from the test sample and the evaluated AgNP standard was determined by inductively coupled plasma mass spectrometry (ICPMS). The presence of both AgNPs and dissolved silver in the extracts was confirmed by single particle (SP)-ICPMS analysis. AgNPs were sized and the particle number concentration determined in the three digestion juices. Experimental results demonstrated differentiated behaviours for AgNP from the standard solution and the meat sample highlighting the relevance of using physiological conditions for accurate risk assessment. In the most realistic scenario assayed (i.e., spiked chicken meat analysis), only 13% of the AgNPs present in the reference material would reach the intestine wall. Meanwhile, other bioaccessible dissolved forms of silver would account for as much as 44% of the silver initially spiked to the meat paste.


Assuntos
Digestão/efeitos dos fármacos , Contaminação de Alimentos/análise , Trato Gastrointestinal/efeitos dos fármacos , Nanopartículas Metálicas/química , Produtos Avícolas/análise , Prata/química , Animais , Galinhas , Trato Gastrointestinal/metabolismo , Humanos , Espectrometria de Massas , Tamanho da Partícula
16.
Circ Res ; 89(7): 573-82, 2001 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-11577022

RESUMO

Ahr is a ligand-activated bHLH/PAS transcription factor involved in cytochrome P450 (CYP) gene regulation and murine susceptibility to atherogenic stimuli. The present studies were conducted to examine constitutive and inducible expression of Cyp1a1 and Cyp1b1 in vascular smooth muscle cells (VSMCs) from Ahr(+/+) and Ahr(-/-) mice. Cyp1a1 mRNA was not expressed constitutively in VSMCs irrespective of Ahr phenotype. Although Cyp1a1 was inducible in Ahr(+/+) by 3 micromol/L benzo(a)pyrene, a known hydrocarbon inducer, the protein was uninducible. In contrast, Cyp1b1 mRNA and protein were expressed under constitutive and inducible conditions irrespective of Ahr phenotype or growth status. CYP-encoded aryl hydrocarbon hydroxylase activity was higher in Ahr(-/-) VSMCs under constitutive conditions and induced by benzo(a)pyrene in Ahr(+/+) and Ahr(-/-) VSMCs. CYP expression was influenced by mitogenic status, because randomly cycling cells consistently exhibited higher levels than growth-arrested counterparts. Actinomycin D (2 microgram/mL) or cycloheximide (10 micromol/L) did not inhibit constitutive or hydrocarbon-inducible aryl hydrocarbon hydroxylase activity in VSMCs. These data indicate that in murine VSMCs, expression of Cyp1al and Cyp1b1 is differentially influenced by Ahr phenotype and mitogenic status, with patterns that may dictate inherent susceptibility to atherogenic stimuli.


Assuntos
Citocromo P-450 CYP1A1/biossíntese , Sistema Enzimático do Citocromo P-450/biossíntese , Regulação da Expressão Gênica/fisiologia , Músculo Liso Vascular/enzimologia , Animais , Aorta , Hidrocarboneto de Aril Hidroxilases/metabolismo , Benzo(a)pireno/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1B1 , Sistema Enzimático do Citocromo P-450/genética , Dimetil Sulfóxido/farmacologia , Ativação Enzimática/efeitos dos fármacos , Ativadores de Enzimas/farmacologia , Indução Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Sequências Hélice-Alça-Hélice/fisiologia , Camundongos , Camundongos Knockout , Mitose/fisiologia , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Fenótipo , Dibenzodioxinas Policloradas/farmacologia , RNA Mensageiro/metabolismo , Receptores de Hidrocarboneto Arílico/deficiência , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo
17.
Talanta ; 151: 83-90, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26946013

RESUMO

Silver migration from a commercial baby feeding bottle and a food box containing AgNPs, as confirmed by SEM-EDX analysis, was evaluated using food simulant solutions [i.e., water, 3% (v/v) acetic acid, and 10% and 90% (v/v) ethanol]. Silver release was investigated at temperatures in the 20-70°C range using contact times of up to 10 days. Migration of silver from the food box was in all cases 2 to 3 orders of magnitude higher than that observed for the baby bottle, although the total silver content in the original box material was half of that found in the baby bottle. As expected, for both food containers, silver migration depended on both the nature of the tested solution and the applied conditions. The highest release was observed for 3% acetic acid at 70°C for 2h, corresponding to 62ngdm(2) and 1887ngdm(-2) of silver for the baby bottle and the food box, respectively. Single particle-inductively coupled plasma mass spectrometry (SP-ICPMS) was used to characterise and quantify AgNPs in the food simulants extracts. Sample preparation was optimized to preserve AgNPs integrity. The experimental parameters affecting AgNPs detection, sizing and quantification by SP-ICPMS were also optimised. Analyses of water and acidic extracts revealed the presence of both dissolved silver and AgNPs. Small AgNPs (in the 18-30nm range) and particle number concentrations within the 4-1510 10(6)L(-1) range were detected, corresponding to only 0.1-8.6% of the total silver released from these materials. The only exception was AgNPs migrated into water at 40°C and 70°C from the food box, which accounted for as much as 34% and 69% of the total silver content, respectively.


Assuntos
Embalagem de Alimentos/métodos , Espectrometria de Massas/métodos , Nanopartículas Metálicas/química , Plásticos/química , Prata/análise , Ácido Acético/química , Contaminação de Alimentos/análise , Humanos , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Reprodutibilidade dos Testes , Prata/química , Temperatura , Fatores de Tempo , Água/química
18.
Rev Sci Instrum ; 87(11): 11E706, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910424

RESUMO

Consumer imaging sensors (CIS) are examined for real-time charged-particle detection and CR-39 plastic detector replacement. Removing cover glass from CIS is hard if not impossible, in particular for the latest inexpensive webcam models. We show that $10-class CIS are sensitive to MeV and higher energy protons and α-particles by using a 90Sr ß-source with its cover glass in place. Indirect, real-time, high-resolution detection is also feasible when combining CIS with a ZnS:Ag phosphor screen and optics. Noise reduction in CIS is nevertheless important for the indirect approach.

19.
Toxicol Sci ; 88(1): 231-41, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16120747

RESUMO

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and similar environmental contaminants have been demonstrated to be potent cardiovascular teratogens in developing piscine and avian species. In the present study, we investigated the effects of TCDD on gene expression during murine cardiovascular development. C57Bl6N pregnant mice were dosed with 1.5, 3.0, or 6.0 microg TCDD/kg on gestational day (GD) 14.5, and microarray analysis was used to characterize the global changes in fetal cardiac gene expression on GD 17.5. TCDD significantly altered expression of a number of genes involved in xenobiotic metabolism, cardiac homeostasis, extracellular matrix production/remodeling, and cell cycle regulation. Interestingly, while the AhR-responsive genes Cyp1A1, Cyp1B1, Ugt1a6, and Ahrr, were all induced by TCDD in the fetal murine heart, other AhR-responsive genes, Cyp1a2, Nqo1, and Gsta1, were not. Quantitative real-time polymerase chain reactions confirmed the changes in expression of several G1/S-type cyclins and extracellular matrix-related genes. These results demonstrate the global changes in cardiac gene expression that result from TCDD exposure of the fetal murine heart and implicate genes involved in cell cycle and extracellular matrix regulation in TCDD-induced cardiac teratogenicity and functional deficits.


Assuntos
Ciclo Celular/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Matriz Extracelular/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Coração/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , Teratogênicos/toxicidade , Animais , Ciclo Celular/genética , Relação Dose-Resposta a Droga , Matriz Extracelular/genética , Feminino , Desenvolvimento Fetal , Perfilação da Expressão Gênica , Coração/embriologia , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Gravidez , RNA Mensageiro/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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