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1.
Phys Rev Lett ; 131(17): 171901, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37955487

RESUMO

The first observation and study of two new baryonic structures in the final state Ξ_{b}^{0}π^{+}π^{-} and the confirmation of the Ξ_{b}(6100)^{-} state in the Ξ_{b}^{-}π^{+}π^{-} decay mode are reported using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb^{-1}. In addition, the properties of the known Ξ_{b}^{*0}, Ξ_{b}^{'-} and Ξ_{b}^{*-} resonances are measured with improved precision. The new decay mode of the Ξ_{b}^{0} baryon to the Ξ_{c}^{+} π^{-} π^{+} π^{-} final state is observed and exploited for the first time in these measurements.

2.
Blood ; 138(15): 1345-1358, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34010414

RESUMO

The blood system serves as a key model for cell differentiation and cancer. It is orchestrated by precise spatiotemporal expression of crucial transcription factors. One of the key master regulators in the hematopoietic systems is PU.1. Reduced levels of PU.1 are characteristic for human acute myeloid leukemia (AML) and are known to induce AML in mouse models. Here, we show that transcriptional downregulation of PU.1 is an active process involving an alternative promoter in intron 3 that is induced by RUNX transcription factors driving noncoding antisense transcription. Core-binding factor (CBF) fusions RUNX1-ETO and CBFß-MYH11 in t(8;21) and inv(16) AML, respectively, activate the PU.1 antisense promoter that results in a shift from sense toward antisense transcription and myeloid differentiation blockade. In patients with CBF-AML, we found that an elevated antisense/sense transcript and promoter accessibility ratio represents a hallmark compared with normal karyotype AML or healthy CD34+ cells. Competitive interaction of an enhancer with the proximal or the antisense promoter forms a binary on/off switch for either myeloid or T-cell development. Leukemic CBF fusions thus use a physiological mechanism used by T cells to decrease sense transcription. Our study is the first example of a sense/antisense promoter competition as a crucial functional switch for gene expression perturbation by oncogenes. Hence, this disease mechanism reveals a previously unknown Achilles heel for future precise therapeutic targeting of oncogene-induced chromatin remodeling.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade beta de Fator de Ligação ao Core/genética , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/genética , Proteínas Proto-Oncogênicas/genética , Transativadores/genética , Elementos Antissenso (Genética)/genética , Linhagem Celular Tumoral , Fusão Gênica , Humanos , Proteínas de Fusão Oncogênica/genética , Regiões Promotoras Genéticas , Proteína 1 Parceira de Translocação de RUNX1/genética , Células Tumorais Cultivadas
3.
J Comp Pathol ; 162: 29-42, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30060840

RESUMO

Endomyocarditis is a commonly detected post-mortem finding in domestic cats presenting for sudden onset cardiovascular death, yet the aetiology remains unresolved. Cats are documented reservoir hosts for Bartonella henselae, the infectious cause of cat scratch disease in man. Various Bartonella spp. have been associated with culture-negative endocarditis, myocarditis and sudden death in man and animals. We hypothesized that Bartonella spp. DNA could be amplified more often from the hearts of cats with feline endomyocarditis-left ventricular endocardial fibrosis (FEMC-LVEF) complex compared with cats with hypertrophic cardiomyopathy (HCM) or cats with grossly and microscopically unremarkable hearts (designated non-cardiac disease controls). Formalin-fixed and paraffin wax-embedded, cardiac tissues from 60 domestic and purebred cats aged 3 months to 18 years were examined, and histological features were recorded. Cardiac tissue sections were tested for Bartonella DNA using multiple 16-23S intergenic transcribed spacer region polymerase chain reaction (PCR) primer sets, including two Bartonella genera, a Bartonella koehlerae species-specific and a Bartonella vinsonii subsp. berkhoffii-specific assay, followed by DNA sequence confirmation of the species or genotype. Special precautions were taken to avoid DNA cross-contamination between tissues. Bartonella spp. DNA was amplified by PCR and sequenced from 18 of 36 cats (50%) with FEMC-LVEF and 1/12 (8.3%) cats with HCM. Bartonella spp. DNA was not amplified from any non-cardiac disease control hearts. Based on PCR/DNA sequencing, one Bartonella spp. was amplified from 10 cats, while the remaining eight were coinfected with more than one Bartonella spp. To our knowledge, this study represents the first documentation of B. vinsonii subsp. berkhoffii genotype I infection in cats (n = 11). Fluorescence in-situ hybridization testing facilitated visualization of Bartonella bacteria within the myocardium of four of seven PCR-positive FEMC-LVEF hearts. Collectively, these findings support the hypothesis that Bartonella spp. may play a primary role or act as a cofactor in the pathogenesis of FEMC-LVEF. Studies involving cats from other geographical regions and definitive demonstration of Bartonella spp. within regions of inflammation are needed to confirm an association between Bartonella spp. and FEMC-LVEF induced morbidity and mortality in cats.


Assuntos
Infecções por Bartonella/veterinária , Doenças do Gato/microbiologia , Endocardite Bacteriana/veterinária , Miocardite/veterinária , Animais , Bartonella , Gatos , DNA Bacteriano/análise
4.
Aliment Pharmacol Ther ; 48(5): 507-522, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29873091

RESUMO

AIM: To test the cross-immunogenicity of anti-CT-P13 IBD patients' sera to CT-P13/infliximab originator and the comparative antigenicity evoked by CT-P13/infliximab originator sera. METHODS: Sera of patients with IBD with measurable anti-CT-P13 antibodies were tested for their cross-reactivity to 5 batches of infliximab originator and CT-P13. Anti-drug antibody positive sera from treated patients were used to compare antigenic epitopes. RESULTS: All 42 anti-CT-P13 and 37 anti-infliximab originator IBD sera were cross-reactive with infliximab originator and CT-P13 respectively. Concentration of anti-drug antibodies against infliximab originator or CT-P13 were strongly correlated both for IgG1 and IgG4 (P < 0.001). Anti-CT-P13 sera of patients with IBD (n = 32) exerted similar functional inhibition on CT-P13 or infliximab originator TNF binding capacity and showed reduced binding to CT-P13 in the presence of five different batches of CT-P13 and infliximab originator. Anti-CT-P13 and anti-infliximab originator IBD sera selectively enriched phage-peptides from the VH (CDR1 and CDR3) and VL domains (CDR2 and CDR3) of infliximab. Sera reactivity detected major infliximab epitopes in these regions of infliximab in 60%-79% of patients, and no significant differences were identified between CT-P13 and infliximab originator immunogenic sera. Minor epitopes were localised in framework regions of infliximab with reduced antibody reactivity shown, in 30%-50% of patients. Monoclonal antibodies derived from naïve individuals and ADA-positive IBD patients treated with CT-P13 provided comparable epitope specificity to five different batches of CT-P13 and infliximab originator. CONCLUSIONS: These results strongly support a similar antigenic profile for infliximab originator and CT-P13, and point toward a safe switching between the two drugs in anti-drug antibody negative patients.


Assuntos
Anticorpos Monoclonais/imunologia , Epitopos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/imunologia , Infliximab/imunologia , Anticorpos Monoclonais/análise , Anticorpos Monoclonais/química , Anticorpos Monoclonais/uso terapêutico , Medicamentos Biossimilares/uso terapêutico , Estudos de Casos e Controles , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Humanos , Imunoglobulina G/análise , Imunoglobulina G/sangue , Imunoglobulina G/química , Infliximab/uso terapêutico , Biblioteca de Peptídeos
5.
Orthod Craniofac Res ; 2018 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-29927056

RESUMO

OBJECTIVES: To identify the genetic basis of severe tooth agenesis in a family of three affected sisters. PATIENTS AND METHODS: A family of three sisters with severe tooth agenesis was recruited for whole-exome sequencing to identify potential genetic variation responsible for this penetrant phenotype. The unaffected father was tested for specific mutations using Sanger sequencing. Gene discovery was supplemented with in situ hybridization to localize gene expression during human tooth development. RESULTS: We report a nonsense heterozygous mutation in exon 2 of WNT10A c.321C>A[p.Cys107*] likely to be responsible for the severe tooth agenesis identified in this family through the creation of a premature stop codon, resulting in truncation of the amino acid sequence and therefore loss of protein function. In situ hybridization showed expression of WNT10A in odontogenic epithelium during the early and late stages of human primary tooth development. CONCLUSIONS: WNT10A has previously been associated with both syndromic and non-syndromic forms of tooth agenesis, and this report further expands our knowledge of genetic variation underlying non-syndromic forms of this condition. We also demonstrate expression of WNT10A in the epithelial compartment of human tooth germs during development.

6.
Int Endod J ; 51(11): 1271-1278, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29637579

RESUMO

AIM: To evaluate the presence and propagation of defects and their effects on surfaces of nickel-titanium (NiTi) instruments using noncontact, three-dimensional optical profilometry, and to assess the accuracy of this method of investigation. METHODOLOGY: The flute surface areas of instruments from two commercial instrumentation systems, namely Reciproc R25 (n = 5) and WaveOne Primary (n = 5), were assessed and compared before and after performing two instrumentation cycles in simulated root canals in clear resin blocks. All the analyses were conducted on areas measuring 211 × 211 µm, located 3 mm from the tips of the instruments. A quantitative analysis was conducted before and after the first and second instrumentation cycles, using the Sa (average roughness over the measurement field), Sq (root mean square roughness) and Sz (average height over the measurement field) amplitude parameters. All the data were submitted to statistical analysis at a 5% level of significance. RESULTS: There was a significant increase (P = 0.007) in wear in both groups, especially between baseline and the second instrumentation cycle, with significantly higher wear values being observed on WaveOne instruments (Sz median values = 33.68 and 2.89 µm, respectively, for WO and RP groups). A significant increase in surface roughness (P = 0.016 and P = 0.008, respectively, for Sa and Sq) was observed in both groups from the first to the second instrumentation cycle, mostly in WaveOne specimens. Qualitative analysis revealed a greater number of defects on the flute topography of all the instruments after use. CONCLUSIONS: More defects were identified in WaveOne Primary instruments compared to Reciproc R25, irrespective of the evaluation stage. The investigation method provided an accurate, repeatable and reproducible assessment of NiTi instruments at different time-points.


Assuntos
Níquel/química , Preparo de Canal Radicular/instrumentação , Tratamento do Canal Radicular/instrumentação , Titânio/química , Ligas Dentárias/química , Instrumentos Odontológicos , Cavidade Pulpar , Endodontia/instrumentação , Desenho de Equipamento , Falha de Equipamento , Humanos , Imageamento Tridimensional/métodos , Teste de Materiais , Reprodutibilidade dos Testes , Rotação , Propriedades de Superfície , Fatores de Tempo
7.
Arq. bras. med. vet. zootec. (Online) ; 70(1): 147-152, Jan.-Feb. 2018. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-888078

RESUMO

Although goat dairy farms in Brazil may have a higher risk of infection by Neospora caninum than beef farms, risk factor evaluation on a representative population remains to be fully established in Brazil. Accordingly, this study aimed to establish the occurrence of anti-N. caninum antibodies and factors associated with exposure in 406 blood samples from five dairy and three beef goat farms in the state of Paraíba, northeastern Brazil. Anti-N. caninum antibodies were detected by indirect immunofluorescence assay (IFA), with samples considered positive when reacting with dilution ≥ 1:50. A total of 106/406 goats (26.11%; 95% CI: 21.96-30.72%) were seroreactive comprising 2/61 (3.28%), 10/45 (22.22%), 13/50 (26.00%), 17/51 (33.33%) to 29/46 (63.04%) in dairy farms, and from 3/54 (5.56%), 12/50 (24.00%) to 20/49 (40.82%) on the beef farms. No significant associations were found in relation to age, gender, dairy versus beef farms, occurrence of abortions or mummified fetuses, and seroreactivity to N. caninum (P>0.05). In conclusion, goat farms in the state of Paraíba showed the highest occurrence of anti-N. caninum antibodies to date in Brazil.(AU)


Embora as criações caprinas de leite no Brasil possam ter maior probabilidade de risco de infecção por Neospora caninum do que as de carne, a avaliação dos fatores de risco em uma população representativa ainda não está totalmente estabelecida no Brasil. Dessa forma, este estudo teve por objetivo estabelecer a soroprevalência de N. caninum e seus fatores associados à exposição em 406 amostras de sangue de cinco fazendas de leite e três de corte provenientes do estado da Paraíba, região Nordeste do Brasil. A detecção de anticorpos anti-N. caninum foi realizada utilizando-se a reação de imunofluorescência indireta (RIFI), com as amostras consideradas positivas na diluição ≥ 1:50. No total, 106/406 (26,11%; IC 95%: 21,96-30,72%) caprinos foram sororreagentes, variando de 2/61 (3,28%), 10/45 (22,22%), 13/50 (26,00%), 17/51 (33,33%) a 29/46 (63,04%) em fazendas de leite, e de 3/54 (5,56%), 12/50 (24,00%) a 20/49 (40,82%) em fazendas de corte. Não foram observadas associações significativas entre idade, sexo, criação de leite e carne, ocorrência de abortamentos ou fetos mumificados e sororreatividade para N. caninum (P>0,05). Em conclusão, fazendas de caprinos da Paraíba mostraram as mais altas ocorrências de anticorpos anti-N. caninum até o momento no Brasil.(AU)


Assuntos
Animais , Cabras/anormalidades , Estudos Soroepidemiológicos , Neospora/patogenicidade , Técnica Indireta de Fluorescência para Anticorpo
8.
Transplant Proc ; 49(4): 890-892, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28457419

RESUMO

Hematopoietic stem cell transplantation is a potentially curative therapy for a range of malignant and non-malignant hematological diseases. Analysis of chimerism following allogeneic stem cell transplantation has been a routine method for the assessment of engraftment and early detection of graft failure. Lineage-specific chimerism monitoring is progressively used to specifically detect chimerism in one or more cell subsets, which may be undetected in assessment of the whole leukocyte population. The chimerism study in different leukocyte subpopulations increases sensitivity and specificity in the monitoring after transplantation, especially the analysis of T lymphocytes. All peripheral blood samples were separated into mononuclear cells and granulocytes by Ficoll density gradient centrifugation and T, B, and CD34+ was separated by immunomagnetic automatic cell separator. After DNA extraction, chimerism monitoring was performed using short tandem repeat by multiplex polymerase chain reaction followed by capillary electrophoresis. Quantification of chimerism was performed by determining the ratio of peak areas from donor and recipient informative short tandem repeat. Donor-recipient chimerism analysis in patients after allogeneic stem cell transplantation is a practical, feasible, and useful tool that predicts clinical outcomes and provides a guide for suitable therapeutic interventions.


Assuntos
Quimerismo , Rejeição de Enxerto/genética , Transplante de Células-Tronco Hematopoéticas/métodos , Complicações Pós-Operatórias/genética , Quimeras de Transplante/genética , Adulto , Linhagem da Célula , Eletroforese Capilar , Estudos de Viabilidade , Feminino , Rejeição de Enxerto/diagnóstico , Humanos , Contagem de Leucócitos , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Complicações Pós-Operatórias/diagnóstico , Período Pós-Operatório , Recidiva , Sensibilidade e Especificidade , Linfócitos T
9.
Int Endod J ; 50(2): 143-152, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26825427

RESUMO

The aim of this review was to provide a detailed analysis of the literature concerning the correlation between different movement kinematics and the cyclic fatigue resistance of NiTi rotary endodontic instruments. From June 2014 to August 2015, four independent reviewers comprehensively and systematically searched the Medline (PubMed), EMBASE, Web of Science, Scopus and Google Scholar databases for works published since January 2005, using the following search terms: endodontics; nickel-titanium rotary files; continuous rotation; reciprocating motion; cyclic fatigue. In addition to the electronic searches, manual searches were performed to include articles listed in the reference sections of high-impact published articles that were not indexed in the databases. Laboratory studies in English language were considered for this review. The electronic and manual searches resulted in identification of 75 articles. Based on the inclusion criteria, 32 articles were selected for analysis of full-text copies. Specific analysis was then made of 20 articles that described the effects of reciprocating and continuous movements on cyclic fatigue of the instruments. A wide range of testing conditions and methodologies have been used to compare the cyclic fatigue resistance of rotary endodontic instruments. Most studies report that reciprocating motion improves the fatigue resistance of endodontic instruments, compared to continuous rotation, independent of other variables such as the speed of rotation, the angle or radius of curvature of simulated canals, geometry and taper, or the surface characteristics of the NiTi instruments.


Assuntos
Ligas , Endodontia/instrumentação , Movimento , Rotação
10.
Int Endod J ; 50(9): 902-909, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27696455

RESUMO

AIM: To describe a new method for the assessment of nanoscale alterations in the surface topography of nickel-titanium endodontic instruments using a high-resolution optical method and to verify the accuracy of the technique. METHODOLOGY: Noncontact three-dimensional optical profilometry was used to evaluate defects on a size 25, .08 taper reciprocating instrument (WaveOne® ), which was subjected to a cyclic fatigue test in a simulated root canal in a clear resin block. For the investigation, an original procedure was established for the analysis of similar areas located 3 mm from the tip of the instrument before and after canal preparation to enable the repeatability and reproducibility of the measurements with precision. All observations and analysis were taken in areas measuring 210 × 210 µm provided by the software of the equipment. RESULTS: The three-dimensional high-resolution image analysis showed clear alterations in the surface topography of the examined cutting blade and flute of the instrument, before and after use, with the presence of surface irregularities such as deformations, debris, grooves, cracks, steps and microcavities. CONCLUSIONS: Optical profilometry provided accurate qualitative nanoscale evaluation of similar surfaces before and after the fatigue test. The stability and repeatability of the technique enables a more comprehensive understanding of the effects of wear on the surface of endodontic instruments.


Assuntos
Ligas , Instrumentos Odontológicos , Teste de Materiais/métodos , Endodontia/instrumentação , Imageamento Tridimensional , Propriedades de Superfície
11.
Environ Sci Process Impacts ; 18(9): 1208-19, 2016 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-27499386

RESUMO

Biomonitoring is an important tool for the assessment of the quality and functions of ecosystems, providing information about the pollutants present and the direct effects that they exert on organisms. Biomonitoring relies upon the quantification of variables that can be biochemical, genetic, morphological and physiological changes. Such variables are designated as biomarkers, and multiple biomarkers are usually determined simultaneously in order to have a more integrated analysis and information about sublethal early effects of contaminants. In this work, we quantified biomarkers, associated with oxidative stress (glutathione-S-transferases GSTs, and catalase CAT, activities; levels of peroxidative alterations, by the thiobarbituric acid reactive substances assay, TBARS) and neurotoxicity (acetylcholinesterase activity, AChE) in the polychaete Hediste diversicolor. Organisms were collected at three distinct estuaries, Ria de Aveiro (Laranjo and São Jacinto), Douro River (São Paio, Afurada, and Ribeira da Granja), both impacted by human activities, and Minho River (Seixas), which has been used as a reference site. Obtained data showed the occurrence of anti-oxidant responses, in most samples from contaminated sites, which was not followed however by the occurrence of oxidative damage in organisms from Ria de Aveiro. None of the analyzed organisms had significant impairment of cholinesterasic activity, suggesting the absence of a prior exposure to neurotoxic compounds. In fact, organisms collected at Ria de Aveiro had largely increased AChE activity, suggesting an uncommon paradoxical biological response that is further discussed.


Assuntos
Poliquetos/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Catalase/metabolismo , Monitoramento Ambiental/métodos , Estuários , Estresse Oxidativo/efeitos dos fármacos , Portugal , Poluentes Químicos da Água/análise
12.
Semergen ; 42(6): 380-7, 2016 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-26364135

RESUMO

OBJECTIVE: The aim of this work is to study the survival of lung cancer patients treated at a referral hospital in Zaragoza (Spain). MATERIAL AND METHOD: The Kaplan-Meier test was used to calculate observed survival. The automatic calculation of the Catalan Institute of Oncology was used to analyse relative survival. RESULTS: Mean survival time was 25.74 months. There was no difference when comparing age groups (P=.151), gender (P=.369), and histological type of tumour (P=.086). Survival by stage of the disease at diagnosis revealed statistically significant differences (P<.001). Relative survival 5 years after diagnosis for the group analysed was 14%. Survival was higher for men (15.5%), in patients under 60 (16.7%) and squamous tumours (18.7%). CONCLUSIONS: Survival by tumour stage was in line with the TNM Staging System for Lung Cancer. These results suggest that overall survival rate for lung cancer in Zaragoza remains very low in the long term, and this depends on the stage of the disease at diagnosis.


Assuntos
Carcinoma/mortalidade , Neoplasias Pulmonares/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Fatores Sexuais , Espanha/epidemiologia , Taxa de Sobrevida , Centros de Atenção Terciária
13.
Int Endod J ; 48(8): 801-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25186632

RESUMO

AIM: Compare the displacement resistance of AH Plus, Ad Seal and Real Seal on dentine discs (DDs) treated with 10% citric acid, 17% EDTA or 2.5% NaOCl, through a new push-out test method. METHODOLOGY: From the middle third of the roots of 15 maxillary central incisors, three dentine discs 1 ± 0.1 mm thick were obtained. On the axial surface of each dentine disc, three 1.2-mm-wide holes were drilled. In the third dentine disc from the same root, each hole was treated with one of three irrigating solutions for 30 s, rinsed with distilled water and dried. Each hole of the same dentine disc was filled with sealer, and the discs were maintained at 37 °C for 7 days. The dentine discs were fixed on a testing machine to test the shear strength. Data were compared using the univariate anova test with a 5% significance level. The Tukey test was used for multiple comparisons. RESULTS: The irrigating solutions did not affect the adhesion of the sealers (P > 0.05). There was no significant difference between the Ad Seal and AHPlus (P > 0.05); however, Real Seal had a significantly lower shear bond strength (P < 0.05). CONCLUSION: The use of different irrigating solutions did not affect resistance to the displacement of resin sealers. Real Seal sealer was less resistant than Ad Seal and AHPlus.


Assuntos
Resinas Compostas/química , Colagem Dentária/métodos , Resinas Epóxi/química , Materiais Restauradores do Canal Radicular/química , Análise do Estresse Dentário , Humanos , Técnicas In Vitro , Incisivo , Teste de Materiais , Irrigantes do Canal Radicular/química , Resistência ao Cisalhamento
14.
Cell Death Differ ; 21(10): 1560-74, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24832466

RESUMO

The relationship between mitochondrial metabolism and cell viability and differentiation in stem cells (SCs) remains poorly understood. In the present study, we compared mitochondrial physiology and metabolism between P19SCs before/after differentiation and present a unique fingerprint of the association between mitochondrial activity, cell differentiation and stemness. In comparison with their differentiated counterparts, pluripotency of P19SCs was correlated with a strong glycolytic profile and decreased mitochondrial biogenesis and complexity: round, low-polarized and inactive mitochondria with a closed permeability transition pore. This decreased mitochondrial capacity increased their resistance against dichloroacetate. Thus, stimulation of mitochondrial function by growing P19SCs in glutamine/pyruvate-containing medium reduced their glycolytic phenotype, induced loss of pluripotent potential, compromised differentiation and became P19SCs sensitive to dichloroacetate. Because of the central role of this type of SCs in teratocarcinoma development, our findings highlight the importance of mitochondrial metabolism in stemness, proliferation, differentiation and chemoresistance. In addition, the present work suggests the regulation of mitochondrial metabolism as a tool for inducing cell differentiation in stem line therapies.


Assuntos
Células-Tronco de Carcinoma Embrionário/citologia , Mitocôndrias/metabolismo , Células-Tronco Neoplásicas/citologia , Células-Tronco Pluripotentes/citologia , Trifosfato de Adenosina/biossíntese , Animais , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Variações do Número de Cópias de DNA/genética , Ácido Dicloroacético/farmacologia , Metabolismo Energético , Glucose/metabolismo , Potencial da Membrana Mitocondrial/fisiologia , Camundongos , Consumo de Oxigênio , Esferoides Celulares , Teratocarcinoma/embriologia , Células Tumorais Cultivadas
15.
Sci Total Environ ; 488-489: 208-19, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24836129

RESUMO

The purpose of this study was to evaluate the potential impact of the pesticides detected in the Alqueva reservoir (Guadiana Basin, South Iberian Peninsula) on the aquatic organisms belonging to this ecosystem. For this purpose, the occurrence and risk assessment of 25 pesticides and of a number of their degradation products were determined in the Alqueva surface waters. The areas (sampling stations) most polluted by pesticides were Sra. Ajuda, Lucefecit and Álamos in the northern and in the middle portions of the reservoir, respectively. The aquatic risk assessment revealed that from the various compounds analysed terbuthylazine, chlorfenvinphos and diazinon presented non-acceptable risk when maximum concentrations were used as the measured environmental concentrations (MEC). The locations that had more samples with risk quotients higher than 1 (high risk) were Sra. Ajuda followed by Lucefécit. The use of risk assessment allowed us to conclude that, despite that the pesticides' concentrations in the water column fulfil the European environmental quality standards, a number of the compounds show a high ecotoxicological risk for the aquatic organisms in the Alqueva ecosystem. The results thereby demonstrate that to have an efficient risk management process, the regulatory authorities of each country must consider an integrative chemical and ecotoxicological approach.


Assuntos
Monitoramento Ambiental , Praguicidas/análise , Poluentes Químicos da Água/análise , Animais , Organismos Aquáticos , Ecossistema , Água Doce/química , Portugal , Medição de Risco
16.
Sci Total Environ ; 470-471: 780-90, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24184750

RESUMO

The purpose of this work was to evaluate the dynamic of the water quality from the Alqueva reservoir (Guadiana River Basin, Portugal) and identify the most important parameters that influence its ecological and chemical status. The results could indicate preventive and/or remediation actions that are necessary to improve its quality and status. Water and sediment samples were collected between 2011 and 2012, at five sampling stations, and analyzed for: (i) water - pH, temperature, dissolved oxygen, electrical conductivity, chloride, total phosphorus, total nitrogen, ammonium, nitrate, nitrite, biochemical and chemical oxygen demand, total Fe, Mn, and As; and (ii) sediments - pH, electrical conductivity, organic matter, total nitrogen, total phosphorus, major and trace elements. The results from the water column showed that the organic descriptors exceeded the Portuguese guideline values for water quality for multiple uses at most of the sampling stations. As for nutrients, Ajuda is the station where the concentrations of the total nitrogen and total phosphorus exceeded the guideline values in most months. Ammonium achieved concentrations above the allowed, during the study, in all locations. Trace elements were more abundant in the sediments, surpassing the maximum levels for the protection of aquatic life for As, Cd and Pb, at Alcarrache, Lucefécit and Álamos, respectively. The use of multivariate analysis showed that the major parameters that explained the water quality variability were the nutrients in the water column, and trace elements in the sediments. Comparing the results from this study with results obtained since 2006, we can observe an obvious increment of the organic descriptors and nutrients in the water body. Further, several parameters and observations indicate an increase of the eutrophication process. So, it is urgent to develop preventive actions and remediation processes to stop the degradation so as to improve the quality of the water in this reservoir.


Assuntos
Monitoramento Ambiental , Água Doce/química , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Nitrogênio/análise , Fósforo/análise , Portugal , Análise Espaço-Temporal , Poluição Química da Água/estatística & dados numéricos
17.
Environ Geochem Health ; 36(2): 209-23, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23990124

RESUMO

In order to study the pollution of an aquatic ecosystem, it is necessary to analyze not only the levels of chemical pollutants in water, but also those accumulated in the sediment matrix, as well as to assess its ecotoxicological status. The Alqueva reservoir, the largest artificial lake in Europe, was chosen as case study as it constitutes the most important water supply source in southern Portugal. It is located in the Guadiana River Basin, in a semi-arid region with high levels of water scarcity and where agriculture is one of the main activities. The evaluation of sediments comprised: (1) physical and chemical analysis (grain size, pH, organic matter, nitrogen, phosphorus); (2) potentially toxic trace elements (Cu, As, Pb, Cr, Cd, Zn and Ni); and (3) ecotoxicological evaluation with Vibrio fischeri, Thamnocephalus platyurus, Daphnia magna, and Heterocypris incongruens. Total trace element concentrations indicated that As, Cd, and Pb surpassed the Canadian levels for the protection of aquatic life, in most of Alqueva's sites. The results of the toxicity assessment showed that some locations induced acute and chronic toxicity in the species used. Further, the H. incongruens was the most sensitive species as far as the contamination found in the sediment is concerned, followed by the bacteria V. fischeri. This integrative approach, together with the water column quality assessment, allowed a comprehensive evaluation of the environmental quality of this strongly modified water body and will allow the implementation of remediation strategies to obtain a good ecological potential as proposed in the Water Framework Directive.


Assuntos
Ecotoxicologia/métodos , Água Doce , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Aliivibrio fischeri/efeitos dos fármacos , Animais , Crustáceos/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Monitoramento Ambiental/métodos , Concentração de Íons de Hidrogênio , Metais/análise , Nitrogênio/análise , Fósforo/análise , Portugal , Testes de Toxicidade Crônica
18.
Osteoporos Int ; 24(10): 2707-12, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23632825

RESUMO

SUMMARY: We investigated vitamin D status in Brazilian cities located at different latitudes. Insufficiency (<50 nmol/L) was common (17 %), even in those living in a tropical climate. Vitamin D insufficiency increased as a function of latitude. Mean 25-hydroxyvitamin D (25(OH)D) levels in each site and latitude correlation were very high (r = -0.88; p=0.02). [corrected]. INTRODUCTION: Inadequate vitamin D, determined by low levels of 25(OH)D, has become very common despite the availability of sunlight at some latitudes. National data from a country that spans a wide range of latitudes would help to determine to what extent latitude or other factors are responsible for vitamin D deficiency. We investigated vitamin D status in cities located at different latitudes in Brazil, a large continental country. METHODS: The source is the Brazilian database from the Generations Trial (1,933 osteopenic or osteoporotic postmenopausal women (60 to 85 years old) with 25(OH)D measurements). 25(OH)D below 25 nmol/L (10 ng/mL) was an exclusion criterion. Baseline values were between fall and winter. The sites included Recife, Salvador, Rio de Janeiro, São Paulo, Curitiba, and Porto Alegre. Mean and standard deviation of 25(OH)D, age, spine and femoral neck T-score, calcium, creatinine, and alkaline phosphatase were calculated for each city. Pearson correlation was used for 25(OH)D and latitude. RESULTS: Insufficiency (<50 or <20 ng/mL) was common (329 subjects, 17 %). Vitamin D insufficiency increased as a function of latitude, reaching 24.5 % in the southernmost city, Porto Alegre. The correlation between mean 25(OH)D levels in each site and latitude was very high (r = -0.88, p < 0.0001). CONCLUSION: There is a high percentage of individuals with vitamin D insufficiency in Brazil, even in cities near the equator, and this percentage progressively increases with more southern latitudes.


Assuntos
Pós-Menopausa/sangue , Deficiência de Vitamina D/epidemiologia , Vitamina D/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Brasil/epidemiologia , Bases de Dados Factuais , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/sangue , Prevalência , Pigmentação da Pele , Luz Solar , Saúde da População Urbana/estatística & dados numéricos , Vitamina D/sangue , Deficiência de Vitamina D/sangue
19.
Enferm. glob ; 11(28): 23-30, oct. 2012. tab
Artigo em Espanhol | IBECS | ID: ibc-105573

RESUMO

Las úlceras venosas representan cerca de 70% a 90% de los casos de úlceras de pierna, estando asociadas a la insuficiencia venosa crónica. El estudio tuvo como objetivo demostrar la importancia de la asistencia de enfermería al paciente portador de úlcera venosa. Estudio de caso, desarrollado en una institución hospitalaria, en Fortaleza-Ceará-Brasil, durante el mes de marzo de 2010, con un paciente portador de insuficiencia venosa, presentando úlcera venosa en miembro inferior izquierdo. Para la obtención de los datos se utilizó como base la Sistematización de la Asistencia de Enfermería (SAE). Fue realizada la entrevista con el paciente y acompañante, consulta al prontuario y examen físico del paciente, siendo este aclarado en cuanto a los objetivos e importancia del estudio. Fueron levantados los problemas e identificados los siguientes diagnósticos de enfermería según la Taxonomía de la NANDA 2007-2008: integridad tisular perjudicada relacionada a la circulación afectada y factores mecánicos; deambulación afectada relacionada a perjuicio cognitivo, neuromuscular y musculo-esquelético y fuerza muscular insuficiente; dolor crónico relacionado con incapacidad física crónica; ansiedad relacionada con estado de salud afectado; y disturbio en la imagen corporal relacionado con lesión. Posteriormente fueron planificadas las intervenciones de enfermería. Es fundamental el papel de la enfermería en los cuidados al paciente portador de úlcera venosa, por tratarse de una enfermedad crónica, con recuperación lenta, con posibilidad de recidivas e implicaciones importantes en la vida del paciente (AU)


Venous ulcers account for about 70% to 90% of leg ulcer cases and are associated with chronic venous insufficiency. The study was aimed to demonstrate the importance of nursing care towards patients with venous ulcers. The case study was developed in a hospital in Fortaleza, Ceara, Brazil, during the month of March 2010, with a patient with venous insufficiency and venous ulcers in the left leg. To obtain the data the Systematization of Nursing Care (SNC) was used as a basis. An Interview was performed with the patient and attendant, with consultations to medical records and the physical examination of the patient, who was informed about the objectives and importance of the study. The problems were raised and identified following nursing diagnoses according to NANDA Taxonomy 2007-2008: impaired tissular integrity related to impaired circulation and mechanical factors, impaired ambulation related to cognitive impairment, neuromuscular and musculoskeletal and muscular strength insufficient; chronic pain related to chronic physical disability, anxiety related to impaired health; and body image disturbance in connection with the injury. Later were planned nursing interventions. It is essential to the role of nurse care to patients with venous ulcers because it is a chronic disease with a slow recovery and with the possibility of recurrence and potential major implications for the patient's life (AU)


Assuntos
Humanos , Masculino , Idoso de 80 Anos ou mais , Úlcera da Perna/enfermagem , Úlcera Varicosa/enfermagem , Cuidados de Enfermagem/tendências , Cuidados de Enfermagem , Qualidade de Vida , Promoção da Saúde , Promoção da Saúde/métodos , Serviços Preventivos de Saúde , Serviços Preventivos de Saúde/organização & administração
20.
J Evol Biol ; 25(11): 2171-80, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22905893

RESUMO

Song learning has evolved within several avian groups. Although its evolutionary advantage is not clear, it has been proposed that song learning may be advantageous in allowing birds to adapt their songs to the local acoustic environment. To test this hypothesis, we analysed patterns of song adjustment to noisy environments and explored their possible link to song learning. Bird vocalizations can be masked by low-frequency noise, and birds respond to this by singing higher-pitched songs. Most reports of this strategy involve oscines, a group of birds with learning-based song variability, and it is doubtful whether species that lack song learning (e.g. suboscines) can adjust their songs to noisy environments. We address this question by comparing the degree of song adjustment to noise in a large sample of oscines (17 populations, 14 species) and suboscines (11 populations, 7 species), recorded in Brazil (Manaus, Brasilia and Curitiba) and Mexico City. We found a significantly stronger association between minimum song frequency and noise levels (effect size) in oscines than in suboscines, suggesting a tighter match in oscines between song transmission capacity and ambient acoustics. Suboscines may be more vulnerable to acoustic pollution than oscines and thus less capable of colonizing cities or acoustically novel habitats. Additionally, we found that species whose song frequency was more divergent between populations showed tighter noise-song frequency associations. Our results suggest that song learning and/or song plasticity allows adaptation to new habitats and that this selective advantage may be linked to the evolution of song learning and plasticity.


Assuntos
Aves/fisiologia , Aprendizagem , Ruído , Canto , Adaptação Psicológica , Animais , Evolução Biológica , Brasil , Ecossistema , Meio Ambiente , Modelos Lineares , México , Seleção Genética , Especificidade da Espécie
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