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1.
Brain ; 147(4): 1166-1189, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38284949

RESUMO

Polyglutamine disorders are a complex group of incurable neurodegenerative disorders caused by an abnormal expansion in the trinucleotide cytosine-adenine-guanine tract of the affected gene. To better understand these disorders, our dependence on animal models persists, primarily relying on transgenic models. In an effort to complement and deepen our knowledge, researchers have also developed animal models of polyglutamine disorders employing viral vectors. Viral vectors have been extensively used to deliver genes to the brain, not only for therapeutic purposes but also for the development of animal models, given their remarkable flexibility. In a time- and cost-effective manner, it is possible to use different transgenes, at varying doses, in diverse targeted tissues, at different ages, and in different species, to recreate polyglutamine pathology. This paper aims to showcase the utility of viral vectors in disease modelling, share essential considerations for developing animal models with viral vectors, and provide a comprehensive review of existing viral-based animal models for polyglutamine disorders.


Assuntos
Peptídeos , Expansão das Repetições de Trinucleotídeos , Animais , Peptídeos/genética , Modelos Animais de Doenças , Transgenes
2.
Mol Ther ; 30(1): 370-387, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34298131

RESUMO

Machado-Joseph disease (MJD) is a fatal neurodegenerative disorder clinically characterized by prominent ataxia. It is caused by an expansion of a CAG trinucleotide in ATXN3, translating into an expanded polyglutamine (polyQ) tract in the ATXN3 protein, that becomes prone to misfolding and aggregation. The pathogenesis of the disease has been associated with the dysfunction of several cellular mechanisms, including autophagy and transcription regulation. In this study, we investigated the transcriptional modifications of the autophagy pathway in models of MJD and assessed whether modulating the levels of the affected autophagy-associated transcripts (AATs) would alleviate MJD-associated pathology. Our results show that autophagy is impaired at the transcriptional level in MJD, affecting multiple AATs, including Unc-51 like autophagy activating kinase 1 and 2 (ULK1 and ULK2), two homologs involved in autophagy induction. Reinstating ULK1/2 levels by adeno-associated virus (AAV)-mediated gene transfer significantly improved motor performance while preventing neuropathology in two in vivo models of MJD. Moreover, in vitro studies showed that the observed positive effects may be mainly attributed to ULK1 activity. This study provides strong evidence of the beneficial effect of overexpression of ULK homologs, suggesting these as promising instruments for the treatment of MJD and other neurodegenerative disorders.


Assuntos
Doença de Machado-Joseph , Animais , Ataxina-3/genética , Ataxina-3/metabolismo , Autofagia , Dependovirus/metabolismo , Modelos Animais de Doenças , Doença de Machado-Joseph/genética , Doença de Machado-Joseph/metabolismo , Doença de Machado-Joseph/terapia , Camundongos
3.
Medicina (Kaunas) ; 59(6)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37374254

RESUMO

Background and Objectives: The prevalence of out-of-hospital cardiac arrest (OHCA) has been established as a significant contributor to mortality rates in developed nations. Due to the challenges associated with conducting controlled randomized trials, there exists a necessity for the collection of high-quality data to enhance the comprehension of the impact of interventions. Several nations have initiated efforts to gather information pertaining to out-of-hospital cardiac arrest (OHCA). The Republic of Slovenia has been collecting data from interventions; however, the variables and data attributes have not yet been standardized to comply with international standards. This lack of conformity poses a challenge in making comparisons or drawing inferences. The aim of this study is to identify how to better gather OHCA data in Slovenia. Materials and methods: The Utstein resuscitation registry protocol (UP) was compared to the Slovenian data points that must be gathered in accordance with the Rules on Emergency Medical Service (REMS) during interventions. In addition, we have proposed alternative measures of digitization to enhance pre-hospital data. Results: Missing data points and attribute mismatches were detected in Slovenia. Eight data points necessitated by the UP are gathered in several databases (hospitals, the National Institute of Public Health, dispatch services, intervention reports from first responders, and defibrillator files), but not in the mandated protocols based on REMS. Two data points have variables that do not match those of the UP. A total of 16 data points according to UP are currently not being collected in Slovenia. The advantages and potential drawbacks of digitizing emergency medical services have been discussed. Conclusions: The study has identified gaps in the methods employed for collecting data on OHCA in Slovenia. The assessment conducted serves as a basis for enhancing the process of data collection, integrating quality control measures across the nation, and establishing a nationwide registry for out-of-hospital cardiac arrest (OHCA) in Slovenia.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Humanos , Reanimação Cardiopulmonar/métodos , Parada Cardíaca Extra-Hospitalar/epidemiologia , Parada Cardíaca Extra-Hospitalar/terapia , Eslovênia/epidemiologia , Coleta de Dados , Sistema de Registros
4.
Gene Ther ; 29(12): 665-679, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36316447

RESUMO

Recombinant adeno-associated virus (rAAV) has become one of the most promising gene delivery systems for both in vitro and in vivo applications. However, a key challenge is the lack of suitable imaging technologies to evaluate delivery, biodistribution and tropism of rAAVs and efficiently monitor disease amelioration promoted by AAV-based therapies at a whole-organ level with single-cell resolution. Therefore, we aimed to establish a new pipeline for the biodistribution analysis of natural and new variants of AAVs at a whole-brain level by tissue clearing and light-sheet fluorescence microscopy (LSFM). To test this platform, neonatal C57BL/6 mice were intravenously injected with rAAV9 encoding EGFP and, after sacrifice, brains were processed by standard immunohistochemistry and a recently released aqueous-based clearing procedure. This clearing technique required no dedicated equipment and rendered highly cleared brains, while simultaneously preserving endogenous fluorescence. Moreover, three-dimensional imaging by LSFM allowed the quantitative analysis of EGFP at a whole-brain level, as well as the reconstruction of Purkinje cells for the retrieval of valuable morphological information inaccessible by standard immunohistochemistry. In conclusion, the pipeline herein described takes the AAVs to a new level when coupled to LSFM, proving its worth as a bioimaging tool in tropism and gene therapy studies.


Assuntos
Encéfalo , Imageamento Tridimensional , Animais , Camundongos , Distribuição Tecidual , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência/métodos , Imageamento Tridimensional/métodos , Encéfalo/diagnóstico por imagem
5.
Transp Res Part A Policy Pract ; 158: 285-301, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35291719

RESUMO

The link between transport and land use in urban areas has always been characterized by a slow evolution process. COVID-19 brought, suddenly and unexpectedly, severe changes to the trip structure within urban areas, as several restrictions were combined with individual health fears. This study addresses the impact of the COVID-19 pandemic in the territory of Porto Greater Urban Area, in Portugal, measured under a structural accessibility approach. This was evaluated through a simulation model, combining different destination restrictions in three alternative scenarios during the pandemic and post-COVID, as well as the definition of four different personas, with distinct risk aversion to infections and telecommuting patterns. The results, presented as the spatial configuration of different mobility environments, foster a critical reflection on their implication for future transportation and land use policies. This pandemic has shown that the territory behaves differently under a critical lockdown scenario, where active modes gain predominance to satisfy most travel needs, signalling a potential ability to enforce more sustainable mobility habits. Still, as the territorial configuration tends to the previous state of equilibrium as restrictions are lifted, particularly for non-telecommuters, the need for acting quickly is reinforced. While the growth of telecommuting can induce additional challenges to the management of urban mobility systems, most policy recommendations that were valid in the past will maintain its relevance, as non telecommuters will retain previous travel habits.

6.
BMC Genomics ; 21(1): 590, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32847508

RESUMO

BACKGROUND: Prolonged exposure to elevated free fatty acids induces ß-cell failure (lipotoxicity) and contributes to the pathogenesis of type 2 diabetes. In vitro exposure of ß-cells to the saturated free fatty acid palmitate is a valuable model of lipotoxicity, reproducing features of ß-cell failure observed in type 2 diabetes. In order to map the ß-cell response to lipotoxicity, we combined RNA-sequencing of palmitate-treated human islets with iTRAQ proteomics of insulin-secreting INS-1E cells following a time course exposure to palmitate. RESULTS: Crossing transcriptome and proteome of palmitate-treated ß-cells revealed 85 upregulated and 122 downregulated genes at both transcript and protein level. Pathway analysis identified lipid metabolism, oxidative stress, amino-acid metabolism and cell cycle pathways among the most enriched palmitate-modified pathways. Palmitate induced gene expression changes compatible with increased free fatty acid mitochondrial import and ß-oxidation, decreased lipogenesis and modified cholesterol transport. Palmitate modified genes regulating endoplasmic reticulum (ER) function, ER-to-Golgi transport and ER stress pathways. Furthermore, palmitate modulated cAMP/protein kinase A (PKA) signaling, inhibiting expression of PKA anchoring proteins and downregulating the GLP-1 receptor. SLC7 family amino-acid transporters were upregulated in response to palmitate but this induction did not contribute to ß-cell demise. To unravel critical mediators of lipotoxicity upstream of the palmitate-modified genes, we identified overrepresented transcription factor binding sites and performed network inference analysis. These identified LXR, PPARα, FOXO1 and BACH1 as key transcription factors orchestrating the metabolic and oxidative stress responses to palmitate. CONCLUSIONS: This is the first study to combine transcriptomic and sensitive time course proteomic profiling of palmitate-exposed ß-cells. Our results provide comprehensive insight into gene and protein expression changes, corroborating and expanding beyond previous findings. The identification of critical drivers and pathways of the ß-cell lipotoxic response points to novel therapeutic targets for type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Apoptose , Humanos , Palmitatos/toxicidade , Proteoma , Proteômica , Transcriptoma
7.
J Shoulder Elbow Surg ; 28(9): 1723-1727, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31014558

RESUMO

BACKGROUND: Subscapularis (SS) lesions are often underdiagnosed because of an incomplete understanding of contributing factors but also because of a greater difficulty in SS tear diagnosis with magnetic resonance imaging or physical examination. In this setting, predicting factors can be useful tools in these injuries' management. The goal of this study was to determine the influence of the coracohumeral distance (CHD) and coracoid overlap (CO) in anterior rotator cuff lesions, as well as to determine the CHD and CO values that can accurately predict SS and long head of the biceps (LHB) injuries. METHODS: We performed a retrospective, controlled, single-blinded study. We analyzed 301 patients with rotator cuff pathology and magnetic resonance imaging studies; patients with SS lesions represented the study group. The CHD and CO were measured. RESULTS: We found that lower CHD and higher CO values were progressively related to more serious injuries of the SS and LHB. The CHD was a very strong predictor of SS injury and tear and a good predictor of LHB injuries. A CHD of 7.6 mm had a sensitivity of 84.4% and specificity of 88.6% for SS tears. The CO was also a very strong predictor of SS tears and a good predictor of LHB injury, with a CO of 16.6 mm reaching a sensitivity of 77.8% and specificity of 68.3% for SS tears. CONCLUSIONS: The CHD is an excellent predictor of SS tears and a good predictor of LHB lesions, with the CO also being a very strong predictor of SS tears and a good model for LHB injuries.


Assuntos
Processo Coracoide/diagnóstico por imagem , Cabeça do Úmero/diagnóstico por imagem , Lesões do Manguito Rotador/diagnóstico por imagem , Manguito Rotador/diagnóstico por imagem , Traumatismos dos Tendões/diagnóstico por imagem , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade , Método Simples-Cego
8.
Development ; 141(8): 1726-36, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24715462

RESUMO

Dorsal spinal neurogenesis is orchestrated by the combined action of signals secreted from the roof plate organizer and a downstream transcriptional cascade. Within this cascade, Msx1 and Msx2, two homeodomain transcription factors (TFs), are induced earlier than bHLH neuralizing TFs. Whereas bHLH TFs have been shown to specify neuronal cell fate, the function of Msx genes remains poorly defined. We describe dramatic alterations of neuronal patterning in Msx1/Msx2 double-mutant mouse embryos. The most dorsal spinal progenitor pool fails to express the bHLH neuralizing TF Atoh1, which results in a lack of Lhx2-positive and Barhl2-positive dI1 interneurons. Neurog1 and Ascl1 expression territories are dorsalized, leading to ectopic dorsal differentiation of dI2 and dI3 interneurons. In proportion, the amount of Neurog1-expressing progenitors appears unaffected, whereas the number of Ascl1-positive cells is increased. These defects occur while BMP signaling is still active in the Msx1/Msx2 mutant embryos. Cell lineage analysis and co-immunolabeling demonstrate that Atoh1-positive cells derive from progenitors expressing both Msx1 and Msx2. In vitro, Msx1 and Msx2 proteins activate Atoh1 transcription by specifically interacting with several homeodomain binding sites in the Atoh1 3' enhancer. In vivo, Msx1 and Msx2 are required for Atoh1 3' enhancer activity and ChIP experiments confirm Msx1 binding to this regulatory sequence. These data support a novel function of Msx1 and Msx2 as transcriptional activators. Our study provides new insights into the transcriptional control of spinal cord patterning by BMP signaling, with Msx1 and Msx2 acting upstream of Atoh1.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/metabolismo , Fator de Transcrição MSX1/metabolismo , Medula Espinal/metabolismo , Animais , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Sítios de Ligação , Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular/genética , Embrião de Mamíferos/metabolismo , Elementos Facilitadores Genéticos/genética , Interneurônios/citologia , Interneurônios/metabolismo , Camundongos , Dados de Sequência Molecular , Mutação/genética , Ligação Proteica/genética , Transdução de Sinais/genética , Medula Espinal/embriologia , Células-Tronco/metabolismo
9.
Bioorg Med Chem Lett ; 27(4): 733-739, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28129976

RESUMO

Drug efflux pumps confer multidrug resistance to dangerous pathogens which makes these pumps important drug targets. We have synthesised a novel series of compounds based on a 2-naphthamide pharmacore aimed at inhibiting the efflux pumps from Gram-negative bacteria. The archeatypical transporter AcrB from Escherichia coli was used as model efflux pump as AcrB is widely conserved throughout Gram-negative organisms. The compounds were tested for their antibacterial action, ability to potentiate the action of antibiotics and for their ability to inhibit Nile Red efflux by AcrB. None of the compounds were antimicrobial against E. coli wild type cells. Most of the compounds were able to inhibit Nile Red efflux indicating that they are substrates of the AcrB efflux pump. Three compounds were able to synergise with antibiotics and reverse resistance in the resistant phenotype. Compound A3, 4-(isopentyloxy)-2-naphthamide, reduced the MICs of erythromycin and chloramphenicol to the MIC levels of the drug sensitive strain that lacks an efflux pump. A3 had no effect on the MIC of the non-substrate rifampicin indicating that this compound acts specifically through the AcrB efflux pump. A3 also does not act through non-specific mechanisms such as outer membrane or inner membrane permeabilisation and is not cytotoxic against mammalian cell lines. Therefore, we have designed and synthesised a novel chemical compound with great potential to further optimisation as inhibitor of drug efflux pumps.


Assuntos
Amidas/química , Anti-Infecciosos/química , Proteínas de Escherichia coli/antagonistas & inibidores , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Amidas/farmacologia , Amidas/toxicidade , Anti-Infecciosos/farmacologia , Anti-Infecciosos/toxicidade , Sítios de Ligação , Sobrevivência Celular/efeitos dos fármacos , Cloranfenicol/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Eritromicina/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Ligação de Hidrogênio , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Naftóis/química , Estrutura Terciária de Proteína
10.
Diabetologia ; 58(10): 2307-16, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26099855

RESUMO

AIMS/HYPOTHESIS: Proinflammatory cytokines contribute to beta cell damage in type 1 diabetes in part through activation of endoplasmic reticulum (ER) stress. In rat beta cells, cytokine-induced ER stress involves NO production and consequent inhibition of the ER Ca(2+) transporting ATPase sarco/endoplasmic reticulum Ca(2+) pump 2 (SERCA2B). However, the mechanisms by which cytokines induce ER stress and apoptosis in mouse and human pancreatic beta cells remain unclear. The purpose of this study is to elucidate the role of ER stress on cytokine-induced beta cell apoptosis in these three species and thus solve ongoing controversies in the field. METHODS: Rat and mouse insulin-producing cells, human pancreatic islets and human EndoC-ßH1 cells were exposed to the cytokines IL-1ß, TNF-α and IFN-γ, with or without NO inhibition. A global comparison of cytokine-modulated gene expression in human, mouse and rat beta cells was also performed. The chemical chaperone tauroursodeoxycholic acid (TUDCA) and suppression of C/EBP homologous protein (CHOP) were used to assess the role of ER stress in cytokine-induced apoptosis of human beta cells. RESULTS: NO plays a key role in cytokine-induced ER stress in rat islets, but not in mouse or human islets. Bioinformatics analysis indicated greater similarity between human and mouse than between human and rat global gene expression after cytokine exposure. The chemical chaperone TUDCA and suppression of CHOP or c-Jun N-terminal kinase (JNK) protected human beta cells against cytokine-induced apoptosis. CONCLUSIONS/INTERPRETATION: These observations clarify previous results that were discrepant owing to the use of islets from different species, and confirm that cytokine-induced ER stress contributes to human beta cell death, at least in part via JNK activation.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Interferon gama/farmacologia , Interleucina-1beta/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocinas/farmacologia , Inibidores Enzimáticos/farmacologia , Humanos , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Ratos , Ratos Wistar , Ácido Tauroquenodesoxicólico/farmacologia , Fator de Transcrição CHOP/farmacologia , ômega-N-Metilarginina/farmacologia
11.
PLoS Genet ; 8(6): e1002755, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22719265

RESUMO

Mitochondrial translation, essential for synthesis of the electron transport chain complexes in the mitochondria, is governed by nuclear encoded genes. Polymorphisms within these genes are increasingly being implicated in disease and may also trigger adverse drug reactions. Statins, a class of HMG-CoA reductase inhibitors used to treat hypercholesterolemia, are among the most widely prescribed drugs in the world. However, a significant proportion of users suffer side effects of varying severity that commonly affect skeletal muscle. The mitochondria are one of the molecular targets of statins, and these drugs have been known to uncover otherwise silent mitochondrial mutations. Based on yeast genetic studies, we identify the mitochondrial translation factor MEF2 as a mediator of atorvastatin toxicity. The human ortholog of MEF2 is the Elongation Factor Gene (EF-G) 2, which has previously been shown to play a specific role in mitochondrial ribosome recycling. Using small interfering RNA (siRNA) silencing of expression in human cell lines, we demonstrate that the EF-G2mt gene is required for cell growth on galactose medium, signifying an essential role for this gene in aerobic respiration. Furthermore, EF-G2mt silenced cell lines have increased susceptibility to cell death in the presence of atorvastatin. Using yeast as a model, conserved amino acid variants, which arise from non-synonymous single nucleotide polymorphisms (SNPs) in the EF-G2mt gene, were generated in the yeast MEF2 gene. Although these mutations do not produce an obvious growth phenotype, three mutations reveal an atorvastatin-sensitive phenotype and further analysis uncovers a decreased respiratory capacity. These findings constitute the first reported phenotype associated with SNPs in the EF-G2mt gene and implicate the human EF-G2mt gene as a pharmacogenetic candidate gene for statin toxicity in humans.


Assuntos
Respiração Celular/genética , Ácidos Heptanoicos/farmacologia , Mitocôndrias/metabolismo , Fator G para Elongação de Peptídeos , Fatores de Alongamento de Peptídeos/genética , Pirróis/farmacologia , Proteínas de Saccharomyces cerevisiae/genética , Atorvastatina , Morte Celular/genética , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mitocôndrias/genética , Fator G para Elongação de Peptídeos/genética , Fator G para Elongação de Peptídeos/metabolismo , Fator G para Elongação de Peptídeos/fisiologia , Fatores de Alongamento de Peptídeos/metabolismo , Polimorfismo de Nucleotídeo Único , RNA Interferente Pequeno , Ribossomos/genética , Ribossomos/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
12.
Genomics ; 103(4): 264-75, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24462878

RESUMO

Type 1 Diabetes (T1D) is an autoimmune disease where local release of cytokines such as IL-1ß and IFN-γ contributes to ß-cell apoptosis. To identify relevant genes regulating this process we performed a meta-analysis of 8 datasets of ß-cell gene expression after exposure to IL-1ß and IFN-γ. Two of these datasets are novel and contain time-series expressions in human islet cells and rat INS-1E cells. Genes were ranked according to their differential expression within and after 24 h from exposure, and characterized by function and prior knowledge in the literature. A regulatory network was then inferred from the human time expression datasets, using a time-series extension of a network inference method. The two most differentially expressed genes previously unknown in T1D literature (RIPK2 and ELF3) were found to modulate cytokine-induced apoptosis. The inferred regulatory network is thus supported by the experimental validation, providing a proof-of-concept for the proposed statistical inference approach.


Assuntos
Citocinas/metabolismo , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Células Secretoras de Insulina/fisiologia , Animais , Citocinas/farmacologia , Proteínas de Ligação a DNA/genética , Diabetes Mellitus Tipo 1 , Humanos , Células Secretoras de Insulina/efeitos dos fármacos , Interferon gama/metabolismo , Interferon gama/farmacologia , Ilhotas Pancreáticas/fisiologia , Proteínas Proto-Oncogênicas c-ets/genética , Ratos , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/genética , Reprodutibilidade dos Testes , Fatores de Transcrição/genética
13.
Development ; 138(14): 3055-66, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21693521

RESUMO

Vessels are primarily formed from an inner endothelial layer that is secondarily covered by mural cells, namely vascular smooth muscle cells (VSMCs) in arteries and veins and pericytes in capillaries and veinules. We previously showed that, in the mouse embryo, Msx1(lacZ) and Msx2(lacZ) are expressed in mural cells and in a few endothelial cells. To unravel the role of Msx genes in vascular development, we have inactivated the two Msx genes specifically in mural cells by combining the Msx1(lacZ), Msx2(lox) and Sm22α-Cre alleles. Optical projection tomography demonstrated abnormal branching of the cephalic vessels in E11.5 mutant embryos. The carotid and vertebral arteries showed an increase in caliber that was related to reduced vascular smooth muscle coverage. Taking advantage of a newly constructed Msx1(CreERT2) allele, we demonstrated by lineage tracing that the primary defect lies in a population of VSMC precursors. The abnormal phenotype that ensues is a consequence of impaired BMP signaling in the VSMC precursors that leads to downregulation of the metalloprotease 2 (Mmp2) and Mmp9 genes, which are essential for cell migration and integration into the mural layer. Improper coverage by VSMCs secondarily leads to incomplete maturation of the endothelial layer. Our results demonstrate that both Msx1 and Msx2 are required for the recruitment of a population of neural crest-derived VSMCs.


Assuntos
Cabeça/irrigação sanguínea , Cabeça/embriologia , Proteínas de Homeodomínio/metabolismo , Fator de Transcrição MSX1/metabolismo , Músculo Liso Vascular/citologia , Crista Neural/citologia , Transdução de Sinais/fisiologia , Análise de Variância , Animais , Proteínas Morfogenéticas Ósseas/metabolismo , Citometria de Fluxo , Inativação Gênica , Proteínas de Homeodomínio/genética , Imuno-Histoquímica , Hibridização In Situ , Fator de Transcrição MSX1/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Mutantes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tamoxifeno/administração & dosagem , Tamoxifeno/farmacologia , Tomografia/métodos
14.
Food Microbiol ; 38: 219-27, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24290646

RESUMO

This study aimed to assess bacterial spoilage of half shell Pacific and Sydney rock oysters during storage using microbial culture and 16S rRNA pyrosequencing. Odour and pH of oyster meats were also investigated. Estimation of microbiological counts by microbial culture highlighted growth of psychrotrophic bacteria. During storage, odour scores (a score describing deterioration of fresh odours where a score of 1 is fresh and 4 is completely spoiled) increased from 1.0 to 3.0 for Pacific oysters and from 1.3 to 3.4 for Sydney rock oysters. pH results obtained for both species fluctuated during storage (range 6.28-6.73) with an overall increase at end of storage. Pyrosequencing revealed that the majority of bacteria at Day 0 represented taxa from amongst the Proteobacteria, Tenericutes and Spirochaetes that have not been cultured and systematically described. During storage, Proteobacteria became abundant with Pseudoalteromonas and Vibrio found to be dominant in both oyster species at Day 7. Analysis of the pyrosequencing data showed significant differences in bacterial profiles between oyster species and storage time (both P = 0.001). As oysters spoiled, bacterial profiles between oyster species became more similar indicating a common spoilage profile. Data presented here provides detailed insight into the changing bacterial profile of shucked oysters during storage and has identified two genera, Pseudoalteromonas and Vibrio, as being important in spoilage of shucked oysters.


Assuntos
Bactérias/isolamento & purificação , Contaminação de Alimentos/análise , Ostreidae/microbiologia , Frutos do Mar/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Humanos , Ostreidae/química , Pseudoalteromonas/classificação , Pseudoalteromonas/genética , Pseudoalteromonas/crescimento & desenvolvimento , Pseudoalteromonas/isolamento & purificação , Frutos do Mar/análise , Paladar , Vibrio/classificação , Vibrio/genética , Vibrio/crescimento & desenvolvimento , Vibrio/isolamento & purificação
15.
Telemed J E Health ; 20(11): 1027-34, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25083737

RESUMO

BACKGROUND: Telemedicine and e-health have been suggested as one solution for closing the health disparity gap between the developed world and the developing world. Yet evidence is lacking from current successful programs in the developing world and, in particular, from sub-Saharan Africa. The primary objective of our study was to present the preliminary results of our efforts in building the Integrated Telemedicine and e-Health Program for Cabo Verde (ITeHP-CV), with an emphasis on initial utilization and results. MATERIALS AND METHODS: This is a prospective study of data collected while we worked to establish a fully functional, integrated national telemedicine network and virtual education network in Cabo Verde. We used the International Virtual e-Hospital Foundation strategic approach known as "initiate-build-operate-transfer" over a 26-month period (November 2011-December 2013). We describe herein the five main pillars of this process that have been implemented: (1) capacity building; (2) network development and deployment of equipment; (3) implementation of clinical telemedicine; (4) implementation of activities related to continuing medical education, delivered from within the country and from abroad; and (5) establishment and use of the electronic virtual library. RESULTS: Based on comprehensive technical and medical assessment of the country's needs, 10 fully functional telemedicine centers in all nine inhabited islands of the Republic of Cabo Verde have been established. RESULTS are presented under the five main pillars of capacity building, network deployment, implementation of clinical telemedicine, implementation of continuing medical education activities, and establishment of the electronic virtual library. CONCLUSIONS: The ITeHP-CV has been successfully launched, and the initial results are encouraging. The continuity of the program and sustainability are primary goals once the program is transferred fully to the Ministry of Health of Cabo Verde. A long-term follow-up study is required in order to ensure sustainability and continuity goals are met.


Assuntos
Educação a Distância/organização & administração , Educação Médica/organização & administração , Telemedicina/organização & administração , Cabo Verde , Fortalecimento Institucional , Humanos , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos
16.
Healthcare (Basel) ; 12(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338211

RESUMO

While previous studies conducted in sub-Saharan African countries have focused on verifying standards of clinical care and assessing challenges faced by healthcare professionals, the present study fills a gap in the literature in that it explores the factors that may drive the organizational commitment of healthcare professionals in Angola. This study aimed to analyze the relationship between psychological capital and organizational commitment through perceived transformational leadership. Therefore, using the quantitative methodology, a self-report questionnaire was applied to 342 healthcare professionals (174 male, 168 female) from different public and private hospitals located in three large cities in Angola. The results confirmed that psychological capital is positively related to affective commitment and that perceived transformational leadership is a mediating variable of this relationship. Therefore, this study highlights the role of psychological capital and perceived transformational leadership in improving affective commitment in challenging environments.

17.
Value Health Reg Issues ; 41: 80-85, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38262256

RESUMO

OBJECTIVES: Access to innovative and effective medication is a citizen's right. The main objectives of this study were to build an indicator to measure access to medicines within hospitals, the Global Medicines Access Index, and to identify the main existing barriers. METHODS: Cross-sectional study carried out in Portuguese National Health Service hospitals. A consensus methodology (expert panel of 7 members) was used to define which dimensions should be included in the index and the weighting that each should take. The panel identified 6 dimensions: access to innovative medicines, proximity distribution, shortages, access to medicines before financing decision, value-based healthcare, and access to medication depending on cost/funding. Data were collected through an electronic questionnaire (September 2021). RESULTS: The response rate was 61.2%. Most hospitals used medicines with and without marketing authorization before the funding decision. Monitoring and generating evidence of new therapies results is still insufficient. The identified barriers were the administrative burden as the major barrier in purchasing medicines, with a relevant impact on shortages of medicines. Most respondents (87%) had a proximity distribution program, mainly implemented in the pandemic context, and the price/funding model was only identified by 10% as a barrier to access. The 2021 Global Medicines Access Index was 66%. Shortages and value-based use of medicines were the dimensions that had more influence in lowering the index value. CONCLUSIONS: The new formula used to obtain a unique and multidimensional index for access to hospital medicines seems to be more sensitive and objective and will be used to monitor access.


Assuntos
Acessibilidade aos Serviços de Saúde , Estudos Transversais , Humanos , Portugal , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/normas , Inquéritos e Questionários , Preparações Farmacêuticas/provisão & distribuição , Preparações Farmacêuticas/economia , Hospitais/estatística & dados numéricos
18.
J Vis Exp ; (206)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38647283

RESUMO

Adeno-associated virus (AAV) has become an increasingly valuable vector for in vivo gene delivery and is currently undergoing human clinical trials. However, the commonly used methods to purify AAVs make use of cesium chloride or iodixanol density gradient ultracentrifugation. Despite their advantages, these methods are time-consuming, have limited scalability, and often result in vectors with low purity. To overcome these constraints, researchers are turning their attention to chromatography techniques. Here, we present an optimized heparin-based affinity chromatography protocol that serves as a universal capture step for the purification of AAVs. This method relies on the intrinsic affinity of AAV serotype 2 (AAV2) for heparan sulfate proteoglycans. Specifically, the protocol entails the co-transfection of plasmids encoding the desired AAV capsid proteins with those of AAV2, yielding mosaic AAV vectors that combine the properties of both parental serotypes. Briefly, after the lysis of producer cells, a mixture containing AAV particles is directly purified following an optimized single-step heparin affinity chromatography protocol using a standard fast protein liquid chromatography (FPLC) system. Purified AAV particles are subsequently concentrated and subjected to comprehensive characterization in terms of purity and biological activity. This protocol offers a simplified and scalable approach that can be performed without the need for ultracentrifugation and gradients, yielding clean and high viral titers.


Assuntos
Cromatografia de Afinidade , Dependovirus , Vetores Genéticos , Heparina , Dependovirus/genética , Dependovirus/isolamento & purificação , Dependovirus/química , Cromatografia de Afinidade/métodos , Heparina/química , Vetores Genéticos/química , Vetores Genéticos/genética , Humanos , Células HEK293
19.
Front Psychol ; 13: 776839, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35126274

RESUMO

This study aims to analyze the relationship between psychological capital profiles and internal learning in teams. The participants in this study were 480 undergraduate students. We performed a cluster analysis using the SPSS and yielded four distinct psychological capital profiles. The student profile with the highest scores in self-efficacy, optimism, hope, and resilience (Profile 2-Fully PsyCap) exhibited also the highest scores of internal learning in teams. On the other hand, the student profile with the lowest scores in self-efficacy, optimism, hope, and resilience (Profile 1- Empty PsyCap) presented the lowest scores of internal learning in teams. It is also noteworthy that there was no significant relationship between the profile with a positive combination between self-efficacy and hope (profile 4) and the profile that presents the optimism as the only positive psychological capability (profile 3), in the way they relate to internal learning in teams, which led us to reject the second hypothesis of the study. This study reinforces the role of psychological capital in academic settings and suggests that psychological capital profiles can affect internal learning in teams differentially.

20.
Ultrasound J ; 14(1): 28, 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35796809

RESUMO

BACKGROUND: Lung ultrasound (LUS) is a valuable tool to predict and monitor the COVID-19 pneumonia course. However, the influence of cardiac dysfunction (CD) on LUS findings remains to be studied. Our objective was to determine the effect of CD on LUS in hospitalized patients with COVID-19 pneumonia. MATERIAL AND METHODS: Fifty-one patients with COVID-19 pneumonia participated in the study. Focused echocardiography (FoCUS) was carried out on day 1 to separate patients into two groups depending on whether they had FoCUS signs of CD (CD+ vs CD-). LUS scores, based on the thickness of the pleural line, the B-line characteristics, and the presence or not of consolidations, were obtained three times along the patient's admission (D1, D5, D10) and compared between CD+ and CD- patients. A correlation analysis was carried out between LUS scores and the ratio of the arterial partial pressure of oxygen to the fraction of the inspired oxygen (P/F ratio). RESULTS: Twenty-two patients were CD+ and 29 patients were CD-. Among the CD+ patients, 19 were admitted to the intensive care unit (ICU), seven received invasive mechanical ventilation (IMV), and one did not survive. Among the CD- patients, 11 were admitted to the ICU, one received IMV and seven did not survive. CD+ patients showed a significantly lower P/F ratio than CD- patients. However, LUS scores showed no between-group differences, except for fewer subpleural consolidations in the upper quadrants of CD+ than on CD- patients. CONCLUSION: In patients with COVID-19, CD contributed to a worse clinical course, but it did not induce significant changes in LUS. Our findings suggest that pathophysiological factors other than those reflected by LUS may be responsible for the differences in clinical condition between CD+ and CD- patients.

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