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1.
Eur J Prosthodont Restor Dent ; 31(2): 109-115, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35917152

RESUMO

This in-situ study aimed to evaluate the chromatic stability, microhardness, and surfacefree energy of chemically activated acrylic resin (CAAR) samples. Eighty CAAR samples were made and each volunteer (n = 20) received two palatal plates with two sides of groups (without and with glaze application). The samples were exposed to two conditions: the control condition (sucrose 30%) and the test condition (sucrose 30% and 0.12% chlorhexidine). The volunteers used the first palatal device (control condition) for seven days and the second palatal device (test condition) for another seven days, with a seven-day break between them. Then, the ΔΕ00, microhardness, and surface-free energy tests were performed. Analysis of Variance and the Tukey test were used (α = 0.05). The control group with glaze showed higher ΔΕ00 compared to the group without the glaze. The test group with glaze had less ΔΕ00 than their respective controls. In both periods, when the glaze was applied, higher microhardness values were found for all groups. Groups with glaze showed lower roughness and higher surface-free energy than groups without the glaze. The values obtained in this study were satisfactory, showing the clinical efficacy of glaze and the use of 0.12% CH for maintaining the physical and mechanical properties of CAAR.


Assuntos
Resinas Acrílicas , Clorexidina , Humanos , Resinas Acrílicas/química , Cura Luminosa de Adesivos Dentários , Lâmpadas de Polimerização Dentária , Propriedades de Superfície , Teste de Materiais , Dureza
2.
J Food Sci Technol ; 60(2): 783-796, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36712211

RESUMO

Common wheat (Triticum aestivum) is one of the most consumed staple foods used for bakery products. Outer layers of grain present a great diversity of bioactive compounds, especially phenolic compounds (PC). Free and bound PC were extracted from eight genotypes of whole wheat flours (WWF) presenting different technological classifications. These extracts were comprehensively characterized through untargeted metabolomics applying ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MSE) and spectrophotometric analyses. Chemical composition and colorimetry were also determined by classical analyses. Thirty-eight PC were tentatively identified by UHPLC-MSE belonging to three classes (phenolic acids, flavonoids, and other polyphenols), some of them identified in all WWF samples. Bound hydroxycinnamic acids were the main PC found in WWF, especially the trans-ferulic acid and its isomer. No difference was found in starch and protein contents, whereas low-quality flours showed a higher ash content than the superior and medium-quality flours. Total phenolic content (TPC) ranged between 124.5 and 171.4 mg GAE/100 g WWF, which bound PC were responsible for 60% of TPC. Omics data and multivariate statistical analyses were successfully applied to discern the phenolic profile of WWF from different genotypes and technological qualities. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05665-8.

3.
BMC Cancer ; 22(1): 144, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35123419

RESUMO

BACKGROUND: Anastomotic leakage is the most important surgical complication following esophagectomy. A major cause of leakage is ischemia of the gastric tube that is used for reconstruction of the gastrointestinal tract. Generalized cardiovascular disease, expressed by calcifications of the aorta and celiac axis stenosis on a pre-operative CT scan, is associated with an increased risk of anastomotic leakage. Laparoscopic ischemic conditioning (ISCON) aims to redistribute blood flow and increase perfusion at the anastomotic site by occluding the left gastric, left gastroepiploic and short gastric arteries prior to esophagectomy. This study aims to assess the safety and feasibility of laparoscopic ISCON in selected patients with esophageal cancer and concomitant arterial calcifications. METHODS: In this prospective single-arm safety and feasibility trial based upon the IDEAL recommendations for surgical innovation, a total of 20 patients will be included recruited in 2 European high-volume centers for esophageal cancer surgery. Patients with resectable esophageal carcinoma (cT1-4a, N0-3, M0) with "major calcifications" of the thoracic aorta accordingly to the Uniform Calcification Score (UCS) or a stenosis of the celiac axis accordingly to the modified North American Symptomatic Carotid Endarterectomy Trial (NASCET) score on preoperative CT scan, who are planned to undergo esophagectomy are eligible for inclusion. The primary outcome variables are complications grade 2 and higher (Clavien-Dindo classification) occurring during or after laparoscopic ISCON and before esophagectomy. Secondary outcomes include intra- and postoperative complications of esophagectomy and the induction of angiogenesis by biomarkers of microcirculation and redistribution of blood flow by measurement of indocyanine green (ICG) fluorescence angiography. DISCUSSION: We hypothesize that in selected patients with impaired vascularization of the gastric tube, laparoscopic ISCON is feasible and can be safely performed 12-18 days prior to esophagectomy. Depending on the results, a randomized controlled trial will be needed to investigate whether ISCON leads to a lower percentage and less severe course of anastomotic leakage in selected patients. TRIAL REGISTRATION: Clinicaltrials.gov, NCT03896399 . Registered 4 January 2019.


Assuntos
Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Precondicionamento Isquêmico/métodos , Laparoscopia/métodos , Calcificação Vascular/cirurgia , Adolescente , Adulto , Fístula Anastomótica/etiologia , Fístula Anastomótica/prevenção & controle , Neoplasias Esofágicas/complicações , Esofagectomia/efeitos adversos , Estudos de Viabilidade , Feminino , Artéria Gástrica/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Calcificação Vascular/complicações , Adulto Jovem
4.
Diabet Med ; 38(2): e14400, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32918322

RESUMO

AIMS: To evaluate the relationship between self-reported colour-race, genomic ancestry, and metabolic syndrome in an admixed Brazilian population with type 1 diabetes. METHODS: We included 1640 participants with type 1 diabetes. The proportions of European, African and Amerindian genomic ancestries were determined by 46 ancestry informative markers of insertion deletion. Two different sets of analyses were performed to determine whether self-reported colour-race and genomic ancestry were predictors of metabolic syndrome. RESULTS: Metabolic syndrome was identified in 29.8% of participants. In the first model, the factors associated with metabolic syndrome were: female gender (odds ratio 1.95, P < 0.001); diabetes duration (odds ratio 1.04, P < 0.001); family history of type 2 diabetes (odds ratio 1.36, P = 0.019); and acanthosis nigricans (odds ratio 5.93, P < 0.001). Colour-race was not a predictive factor for metabolic syndrome. In the second model, colour-race was replaced by European genomic ancestry. The associated factors were: female gender (odds ratio 1.95, P < 0.001); diabetes duration (odds ratio 1.04, P < 0.001); family history of type 2 diabetes (odds ratio 1.39, P = 0.011); and acanthosis nigricans (odds ratio 6.12, P < 0.001). Physical exercise (≥3 times a week) was a protective factor (odds ratio 0.77, P = 0.041), and European genomic ancestry was not associated with metabolic syndrome but showed an odds ratio of 1.77 (P = 0.05). CONCLUSIONS: Although a higher level of European genomic ancestry was observed among participants with metabolic syndrome in the univariate analysis, this association did not persist after multivariable adjustments. Further prospective studies in other highly admixed populations remain necessary to better evaluate whether the European ancestral component modulates the development of metabolic syndrome in type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/epidemiologia , Exercício Físico/estatística & dados numéricos , Síndrome Metabólica/etnologia , Acantose Nigricans/epidemiologia , Adolescente , Adulto , Indígena Americano ou Nativo do Alasca/genética , Indígena Americano ou Nativo do Alasca/estatística & dados numéricos , População Negra/genética , População Negra/estatística & dados numéricos , Brasil/epidemiologia , Criança , Estudos Transversais , Diabetes Mellitus Tipo 2 , Feminino , Genômica , Humanos , Masculino , Anamnese , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/genética , Pessoa de Meia-Idade , Fatores de Proteção , Fatores de Risco , Fatores Sexuais , População Branca/genética , População Branca/estatística & dados numéricos , Adulto Jovem
5.
Eur Radiol ; 31(6): 4350-4357, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33241515

RESUMO

OBJECTIVES: The blood of patients with anemia demonstrates distinctly lower attenuation in unenhanced CT images. However, the frequent usage of intravenous contrast hampers evaluation of anemia. Spectral detector computed tomography (SDCT) allows for reconstruction of virtual non-contrast images (VNC) from contrast-enhanced data (CE). The purpose of this study was to evaluate whether VNC allow for prediction of anemia. METHODS: Five hundred twenty-two patients with CE-SDCT of the chest and accessible serum hemoglobin (HbS) were retrospectively included. Patients were assigned to three groups (severe anemia, moderate/mild anemia, and healthy) based on recent lab tests (≤ 7 days) for HbS following gender and the WHO definition of anemia. CT attenuation was determined using two ROI in the left ventricular lumen and one ROI in the descending thoracic aorta. ROI were placed on CE and copied to VNC. ANOVA, linear regression, and receiver operating characteristics were used for statistic evaluation. RESULTS: Average HbS was 11.6 ± 2.4 g/dl. Attenuation on VNC showed significant differences between healthy patients, patients with mild/moderate anemia, and severely anemic patients (all p ≤ 0.05). Applying cutoffs of 39.2/37.6 HU and 33.6/32.7 HU allowed to differentiate between healthy, mild/moderately, and severely anemic men/women (AUC 0.857/0.833 and 0.879/0.932). A linear relationship between HbS and attenuation on VNC was established (r2 = 0.54, HbS = - 0.875 + 0.329 × HU). CONCLUSIONS: An approximation of HbS and presence of anemia can be conducted based on simple attenuation measurements in contrast-enhanced SDCT examinations enabled by VNC imaging. KEY POINTS: • While the attenuation of blood is a previously described biomarker for anemia in non-contrast images, virtual non-contrast images from spectral detector CT circumvent this limitation and allow for diagnosis of anemia in contrast-enhanced scans. • Attenuation of blood in virtual non-contrast images derived from spectral detector CT shows a moderate correlation to serum hemoglobin levels. • Presence of anemia be estimated in virtual non-contrast images using proposed cutoffs of 39.2 HU and 37.6 HU for men and women, respectively, to differentiate between healthy and anemic patients.


Assuntos
Anemia , Tórax , Anemia/diagnóstico por imagem , Meios de Contraste , Feminino , Humanos , Masculino , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
6.
Br J Nutr ; 126(5): 782-789, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-33234175

RESUMO

The objectives of this study were to evaluate the cross-cultural measurement equivalence of the Healthy Eating Index (HEI) for children aged 1-2 years and to analyse the quality of nutrition of preterm infants. This was a cross-sectional study with 106 premature infants attended in two specialised outpatient clinics of university hospitals. The quality of the diet was analysed through an adapted HEI to meet the dietary recommendations of Brazilian children aged 1-2 years. Food consumption was measured by 24-h recalls. The reliability of the instrument was evaluated by internal consistency analysis and inter-observer reliability using Cronbach's α coefficient and κ with quadratic ponderation. The construct validity was evaluated by principal component analysis and by Spearman's correlation coefficient with total energy and consumption of some groups' food. The diet quality was considered adequate when the total HEI score was over 80 points. Cronbach's α was 0·54. Regarding inter-observer reliability, ten items showed strong agreement (κ > 0·8). The item scores had low correlations with energy consumed (r ≤ 0·30), and positive and moderate correlation of fruit (r 0·67), meat (r 0·60) and variety of diet (r 0·57) with total scores. When analysing the overall quality of the diet, most patients need improvement (median 78·7 points), which can be attributed to low total vegetable intake and the presence of ultraprocessed foods in the diet. The instrument showed auspicious psychometric properties, being promising to evaluate the quality of the diet in children aged 1-2 years.


Assuntos
Comparação Transcultural , Dieta Saudável , Recém-Nascido Prematuro , Brasil , Estudos Transversais , Humanos , Lactente , Política Nutricional , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
7.
Anim Genet ; 52(4): 505-508, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34106478

RESUMO

The objectives of this study were to provide the buffalo research community with an updated SNP map for the Axiom Buffalo Genotyping (ABG) array with genomic positions for SNP currently unmapped and to map all cattle QTL from the CattleQTLdb onto the buffalo reference assembly. To update the ABG array map, all SNP probe sequences from the ABG array were re-aligned against the UOA_WB_1 assembly. With the new map, the number of mapped markers increased by approximately 10% and went from 106 778 to 116 708, which reduced the average marker spacing by approximately 2 kb. A comparison of results between signatures of autozygosity study using the ABG and the new map showed that, when the additional markers were used there was an increase in the autozygosity peaks and additional peaks in BBU5 and BBU11 could be identified. After sequence alignment and quality control, 64 650 (UMD3.1) and 76 530 (ARS_UCD1.2) cattle QTL were mapped onto the buffalo genome. The mapping of the bovine QTL database onto the buffalo genome should be useful for genome-wide association studies in buffalo and, given the high homology between the two species, the positions of cattle QTL on the buffalo genome can serve as a stepping stone towards a water buffalo QTL database.


Assuntos
Búfalos/genética , Estudo de Associação Genômica Ampla/veterinária , Genótipo , Locos de Características Quantitativas , Animais , Bovinos/genética
8.
J Dairy Sci ; 104(2): 1917-1927, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33272579

RESUMO

Characterization of autozygosity is relevant to monitor genetic diversity and manage inbreeding levels in breeding programs. Identification of autozygosity hotspots can unravel genomic regions targeted by selection for economically important traits and can help identify candidate genes for selection. In this study, we estimated the inbreeding levels of a Brazilian population of Murrah buffalo undergoing selection for milk production traits, particularly milk yield. We also studied the distribution of runs of homozygosity (ROH) islands and identified putative genes and quantitative trait loci (QTL) under selection. We genotyped 422 Murrah buffalo for 51,611 SNP; 350 of these had ROH longer than 10 Mb, indicating the occurrence of inbreeding in the last 5 generations. The mean length of the ROH per animal was 4.28 ± 1.85 Mb. Inbreeding coefficients were calculated from the genomic relationship matrix, the pedigree, and the ROH, with estimates varying between 0.242 and 0.035. Inbreeding estimates from the pedigree had a low correlation with the genomic estimates, and estimates from the genomic relationship matrix were much higher than those from the pedigree or the ROH. Signatures of selection were identified in 6 genomic regions, located on chromosomes 1, 2, 3, 5, 16, and 18, encompassing a total of 190 genes and 174 QTL. Many of the genes (e.g., APRT and ACSF3) and QTL identified are related to milk production traits, such as milk yield, milk fat yield and percentage, and milk protein yield and percentage. Other genes are associated with reproduction and immune response traits as well as morphological aspects of the buffalo species. Inbreeding levels in this population are still low but are increasing due to selection and should be managed to avoid future losses due to inbreeding depression. The proximity of genes linked to milk production traits with genes associated with reproduction and immune system traits suggests the need to include these latter genes in the breeding program to avoid negatively affecting them due to selection for production traits.


Assuntos
Búfalos/genética , Genômica , Leite/metabolismo , Reprodução , Animais , Brasil , Búfalos/fisiologia , Feminino , Genótipo , Homozigoto , Endogamia , Masculino , Linhagem , Fenótipo , Locos de Características Quantitativas/genética
9.
Thorax ; 75(11): 974-981, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32826284

RESUMO

INTRODUCTION: Procalcitonin expression is thought to be stimulated by bacteria and suppressed by viruses via interferon signalling. Consequently, during respiratory viral illness, clinicians often interpret elevated procalcitonin as evidence of bacterial coinfection, prompting antibiotic administration. We sought to evaluate the validity of this practice and the underlying assumption that viral infection inhibits procalcitonin synthesis. METHODS: We conducted a retrospective cohort study of patients hospitalised with pure viral infection (n=2075) versus bacterial coinfection (n=179). The ability of procalcitonin to distinguish these groups was assessed. In addition, procalcitonin and interferon gene expression were evaluated in murine and cellular models of influenza infection. RESULTS: Patients with bacterial coinfection had higher procalcitonin than those with pure viral infection, but also more severe disease and higher mortality (p<0.001). After matching for severity, the specificity of procalcitonin for bacterial coinfection dropped substantially, from 72% to 61%. In fact, receiver operating characteristic curve analysis showed that procalcitonin was a better indicator of multiple indices of severity (eg, organ failures and mortality) than of coinfection. Accordingly, patients with severe viral infection had elevated procalcitonin. In murine and cellular models of influenza infection, procalcitonin was also elevated despite bacteriologic sterility and correlated with markers of severity. Interferon signalling did not abrogate procalcitonin synthesis. DISCUSSION: These studies reveal that procalcitonin rises during pure viral infection in proportion to disease severity and is not suppressed by interferon signalling, in contrast to prior models of procalcitonin regulation. Applied clinically, our data suggest that procalcitonin represents a better indicator of disease severity than bacterial coinfection during viral respiratory infection.


Assuntos
Biomarcadores/metabolismo , Pneumonia Viral/metabolismo , Pró-Calcitonina/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Coinfecção , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Pneumonia Bacteriana/metabolismo , Pneumonia Bacteriana/mortalidade , Pneumonia Viral/mortalidade , Estudos Retrospectivos , Índice de Gravidade de Doença
10.
J Immunol ; 201(2): 615-626, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29891554

RESUMO

Chitinases and chitinase-like proteins are an evolutionary conserved group of proteins. In the absence of chitin synthesis in mammals, the conserved presence of chitinases suggests their roles in physiology and immunity, but experimental evidence to prove these roles is scarce. Chitotriosidase (chit1) is one of the two true chitinases present in mammals and the most prevalent chitinase in humans. In this study, we investigated the regulation and the role of chit1 in a mouse model of Klebsiella pneumoniae lung infection. We show that chitinase activity in bronchoalveolar lavage fluid is significantly reduced during K. pneumoniae lung infection. This reduced activity is inversely correlated with the number of neutrophils. Further, instilling neutrophil lysates in lungs decreased chitinase activity. We observed degradation of chit1 by neutrophil proteases. In a mouse model, chit1 deficiency provided a significant advantage to the host during K. pneumoniae lung infection by limiting bacterial dissemination. This phenotype was independent of inflammatory changes in chit1-/- mice as they exerted a similar inflammatory response. The decreased dissemination resulted in improved survival in chit1-/- mice infected with K. pneumoniae in the presence or absence of antibiotic therapy. The beneficial effects of chit1 deficiency were associated with altered Akt activation in the lungs. Chit1-/- mice induced a more robust Akt activation postinfection. The role of the Akt pathway in K. pneumoniae lung infection was confirmed by using an Akt inhibitor, which impaired health and survival. These data suggest a detrimental role of chit1 in K. pneumoniae lung infections.


Assuntos
Hexosaminidases/metabolismo , Infecções por Klebsiella/imunologia , Klebsiella pneumoniae/fisiologia , Pulmão/imunologia , Macrófagos/fisiologia , Neutrófilos/imunologia , Animais , Extratos Celulares , Modelos Animais de Doenças , Hexosaminidases/genética , Humanos , Pulmão/microbiologia , Camundongos , Proteólise , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células RAW 264.7 , Transdução de Sinais
11.
Clin Radiol ; 75(1): 78.e1-78.e7, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31587801

RESUMO

AIM: To develop a robust open-source method for fully automated extraction of total lung capacity (TLC) from computed tomography (CT) images and to demonstrate its integration into the clinical workflow. MATERIALS AND METHODS: Using only open-source software, an algorithm was developed based on a region-growing method that does not require manual interaction. Lung volumes calculated from reconstructions with different kernels (TLCCT) were assessed. To validate the algorithm calculations, the results were correlated to TLC measured by pulmonary function testing (TLCPFT) in a subgroup of patients for which this information was available within 3 days of the CT examination. RESULTS: A total of 288 patients were analysed retrospectively. Manual review revealed poor segmentation results in 13 (4.5%) patients. In the validation subgroup, the correlation between TLCCT and TLCPFT was r=0.87 (p<0.001). Measurements showed excellent agreement between the two reconstruction kernels with an intraclass correlation coefficient (ICC) of 0.99. Calculation of the volumes took an average of 5 seconds (standard deviation: 3.72 seconds). Integration of the algorithm into the departments of the PACS environment was successful. A DICOM-encapsulated PDF document with measurements and an overlay of the segmentation results was sent to the PACS to allow the radiologists to detect false measurements. CONCLUSIONS: The algorithm developed allows fast and fully automated calculation of lung volume without any additional input from the radiologist. The algorithm delivers excellent segmentation in >95% of cases with significant positive correlations between lung volume on CT and TLC on PFT.


Assuntos
Algoritmos , Medidas de Volume Pulmonar/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodos , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória , Estudos Retrospectivos , Software
12.
Lett Appl Microbiol ; 71(5): 490-497, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32777092

RESUMO

The aim of this study was to synthesize and investigate the in vitro antifungal properties of 23 cinnamyl Schiff bases. In addition, cytotoxic effects of such cinnamyl Schiff bases against human lung, kidney or red blood cells were also checked. The compounds were synthesized in a single-step, 2 min of reaction under microwave irradiation produced up to 97% yield. Six of the 23 cinnamyl Schiff bases possessed antifungal activities against strains of Candida, Aspergillus, Fonsecaea and, particularly, Cryptococcus species. Indeed, cinnamyl Schiff bases 1 and 23 exhibited minimum inhibitory concentration (MIC) values more than twofold lower than fluconazole (FCZ) against all the Cryptococcus neoformans strains (MIC = 1·33, 1·4 and 5·2 µg ml-1 , respectively) and Cryptococcus gattii strains (MIC = 5·3, 2·8 and 9·2 µg ml-1 , respectively) (12 strains of each species) while cinnamyl Schiff base 11 was as potent as FCZ against all strains from both Cryptococcus species. No significant cytotoxic effects were observed for Schiff bases against human lung, kidney or red blood cells, all presenting selective indexes higher than 10. In conclusion, this study revealed cinnamyl Schiff bases, especially 1 and 23, as new lead anticryptococcal agents for the discovery of novel antifungal drugs. SIGNIFICANCE AND IMPACT OF THE STUDY: The occurrence and severity of fungal infections have increased in recent decades due to resistance to available antifungal drugs and the appearance of new emerging pathogens. Thus, the search for new antifungal agents is mandatory. From a series of 23 cinnamyl Schiff bases, two compounds (1 and 23) were interrogated as new anticryptococcal agents without significant cytotoxicity against human lung, kidney or red blood cells. In turns, these new Schiff bases are lead compounds for the discovery of novel antifungal drugs.


Assuntos
Antifúngicos/farmacologia , Micoses/tratamento farmacológico , Bases de Schiff/farmacologia , Antifúngicos/síntese química , Antineoplásicos/farmacologia , Aspergillus/efeitos dos fármacos , Candida/efeitos dos fármacos , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Fluconazol/farmacologia , Fonsecaea/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Bases de Schiff/síntese química
13.
Eur Radiol ; 29(4): 1640-1646, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29980928

RESUMO

OBJECTIVES: To assess undergraduate medical students' attitudes towards artificial intelligence (AI) in radiology and medicine. MATERIALS AND METHODS: A web-based questionnaire was designed using SurveyMonkey, and was sent out to students at three major medical schools. It consisted of various sections aiming to evaluate the students' prior knowledge of AI in radiology and beyond, as well as their attitude towards AI in radiology specifically and in medicine in general. Respondents' anonymity was ensured. RESULTS: A total of 263 students (166 female, 94 male, median age 23 years) responded to the questionnaire. Around 52% were aware of the ongoing discussion about AI in radiology and 68% stated that they were unaware of the technologies involved. Respondents agreed that AI could potentially detect pathologies in radiological examinations (83%) but felt that AI would not be able to establish a definite diagnosis (56%). The majority agreed that AI will revolutionise and improve radiology (77% and 86%), while disagreeing with statements that human radiologists will be replaced (83%). Over two-thirds agreed on the need for AI to be included in medical training (71%). In sub-group analyses male and tech-savvy respondents were more confident on the benefits of AI and less fearful of these technologies. CONCLUSION: Contrary to anecdotes published in the media, undergraduate medical students do not worry that AI will replace human radiologists, and are aware of the potential applications and implications of AI on radiology and medicine. Radiology should take the lead in educating students about these emerging technologies. KEY POINTS: • Medical students are aware of the potential applications and implications of AI in radiology and medicine in general. • Medical students do not worry that the human radiologist or physician will be replaced. • Artificial intelligence should be included in medical training.


Assuntos
Inteligência Artificial , Atitude do Pessoal de Saúde , Atitude Frente aos Computadores , Radiologia/educação , Estudantes de Medicina/psicologia , Adulto , Educação de Graduação em Medicina/métodos , Feminino , Alemanha , Humanos , Masculino , Radiologistas , Radiologia/métodos , Inquéritos e Questionários , Adulto Jovem
14.
Lett Appl Microbiol ; 68(2): 120-127, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30408202

RESUMO

Conditions of the acrylic resin (AR) surface, such as roughness, can promote a favourable environment for the adhesion of micro-organisms, even on the surface of ocular prostheses. This study evaluated the influence of photopolymerized glaze application on the roughness of ARs and adhesion of Staphylococcus aureus and Staphylococcus epidermidis on ocular AR surfaces submitted to accelerated ageing. Two hundred and eighty-eight samples of white colour (N1) and colourless ARs were distributed in eight groups (n = 9), based on surface treatments (glaze or ARs submitted to only a final polishing), accelerated ageing (before and after) and periods of microbial growth (24- and 48-h). The roughness average (Ra) and total height of roughness profile (Rt) values were greater for the groups with glaze and increased for all groups after ageing. The microbial adhesion among the groups with and without glaze did not present a statistically significant difference. The ageing did not statistically affect the adhesion of Staph. epidermidis, but affected the adhesion of Staph. aureus, which presented an increase after 24 h of growth on only N1 AR with glaze. These results demonstrate that the glaze did not contribute to adhesion of Staph. aureus and Staph. epidermidis, which are responsible for most ocular prosthetic infections. SIGNIFICANCE AND IMPACT OF THE STUDY: Some recent evidence suggested that the surface finish of ocular prostheses influences the accumulation of deposits that can affect the interaction with pathogenic bacteria, increasing the probability of infections. In addition, surface deterioration over time can increase the roughness and, consequently, biofilm formation. Thus, a better understanding of the influence of surface finish on bacterial adhesion becomes extremely important. In this study, we tested a glaze for surface polishing compared to mechanical polishing, before and after ageing. The results suggest that the glaze did not contribute to microbial adhesion and might be useful in preventing possible prosthetic infections.


Assuntos
Resinas Acrílicas/química , Aderência Bacteriana/fisiologia , Olho Artificial/microbiologia , Staphylococcus aureus/metabolismo , Staphylococcus epidermidis/metabolismo , Propriedades de Superfície
15.
J Dairy Sci ; 102(6): 5279-5294, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30981488

RESUMO

The variance of gametic diversity ( σgamete2) can be used to find individuals that more likely produce progeny with extreme breeding values. The aim of this study was to obtain this variance for individuals from routine genomic evaluations, and to apply gametic variance in a selection criterion in conjunction with breeding values to improve genetic progress. An analytical approach was developed to estimate σgamete2 by the sum of binomial variances of all individual quantitative trait loci across the genome. Simulation was used to verify the predictability of this variance in a range of scenarios. The accuracy of prediction ranged from 0.49 to 0.85, depending on the scenario and model used. Compared with sequence data, SNP data are sufficient for estimating σgamete2 Results also suggested that markers with low minor allele frequency and the covariance between markers should be included in the estimation. To incorporate σgamete2 into selective breeding programs, we proposed a new index, relative predicted transmitting ability, which better utilizes the genetic potential of individuals than traditional predicted transmitting ability. Simulation with a small genome showed an additional genetic gain of up to 16% in 10 generations, depending on the number of quantitative trait loci and selection intensity. Finally, we applied σgamete2 to the US genomic evaluations for Holstein and Jersey cattle. As expected, the DGAT1 gene had a strong effect on the estimation of σgamete2 for several production traits. However, inbreeding had a small impact on gametic variability, with greater effect for more polygenic traits. In conclusion, gametic variance, a potentially important parameter for selection programs, can be easily computed and is useful for improving genetic progress and controlling genetic diversity.


Assuntos
Cruzamento , Bovinos/genética , Células Germinativas , Seleção Genética , Animais , Frequência do Gene , Marcadores Genéticos , Genômica/métodos , Endogamia , Masculino , Modelos Genéticos , Herança Multifatorial , Locos de Características Quantitativas
16.
Faraday Discuss ; 208(0): 269-286, 2018 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-29808836

RESUMO

In this study, we investigated hollow AgAu nanoparticles with the goal of improving our understanding of the composition-dependent catalytic activity of these nanoparticles. AgAu nanoparticles were synthesized via the galvanic replacement method with controlled size and nanoparticle compositions. We studied extinction spectra with UV-Vis spectroscopy and simulations based on Mie theory and the boundary element method, and ultrafast spectroscopy measurements to characterize decay constants and the overall energy transfer dynamics as a function of AgAu composition. Electron-phonon coupling times for each composition were obtained from pump-power dependent pump-probe transients. These spectroscopic studies showed how nanoscale surface segregation, hollow interiors and porosity affect the surface plasmon resonance wavelength and fundamental electron-phonon coupling times. Analysis of the spectroscopic data was used to correlate electron-phonon coupling times to AgAu composition, and thus to surface segregation and catalytic activity. We have performed all-atom molecular dynamics simulations of model hollow AgAu core-shell nanoparticles to characterize nanoparticle stability and equilibrium structures, besides providing atomic level views of nanoparticle surface segregation. Overall, the basic atomistic and electron-lattice dynamics of core-shell AgAu nanoparticles characterized here thus aid the mechanistic understanding and performance optimization of AgAu nanoparticle catalysts.

17.
Epidemiol Infect ; 146(14): 1763-1770, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29991361

RESUMO

The goal of this study was to analyse the spatial pattern of tuberculosis (TB) mortality using different approaches, namely: mortality rates (MR), spatial relative risks (RR) and Bayesian rates (Global and Local) and their association with human development index (HDI), Global and its three dimensions: education, longevity and income. An ecological study was developed in Curitiba, Brazil based on data from Mortality Information System (2008-2014). Spatial scan statistics were used to compute RR and identify high-risk clusters. Bivariate Local Indicator of Spatial Associations was used to assess associations. MR ranged between 0 and 25.24/100.000 with a mean (standard deviation) of 1.07 (2.66). Corresponding values for spatial RR were 0-27.46, 1.2 (2.99) and for Bayesian rates (Global and Local) were 0.49-1.66, 0.90 (0.19) and 0-6.59, 0.98 (0.80). High-risk clusters were identified for all variables, except for HDI-income and Global Bayesian rate. Significant negative spatial relations were found between MR and income; between RR and HDI global, longevity and income; and Bayesian rates with all variables. Some areas presented different patterns: low social development/low risk and high risk/high development. These results demonstrate that social development variables should be considered, in mortality due TB.


Assuntos
Crescimento , Fatores de Risco , Fatores Socioeconômicos , Tuberculose/mortalidade , Teorema de Bayes , Brasil/epidemiologia , Humanos , Risco , Análise Espacial
18.
Transpl Infect Dis ; 20(4): e12894, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29603514

RESUMO

INTRODUCTION: While the growing knowledge on HIV among solid organ transplant recipients (SOT) is limited to either pretransplant infection or allograft transmission, there are only sparse reports describing HIV-infection after transplantation through sexual route, the primary mode of transmission in the general population. METHODS: From two different centers, we report nine new cases of HIV infection in SOT recipients attributed to sexual acquisition: eight cases of kidney-transplant recipients and one heart-transplant recipient. FINDINGS: There were nine cases of post-transplant HIV-infection detected among 14 526 transplants performed 1998 to 2015. In 6/9 cases, infection was contracted 5 years after SOT. All but one patient had stable allograft function under immunosuppressive therapy. The main trigger to diagnosis was late CMV disease and sexually transmitted diseases; five patients had CDC-stage 3 HIV infection. In 7/9 patients, virologic response and CD4 recovery were achieved within 3 months after starting antiretroviral therapy (ART). After an average of 3.6 years post diagnosis, 5/9 patients remained alive with well-controlled infection and functioning allograft. CONCLUSION: Sexual acquisition of HIV infection after SOT represents a difficult challenge, as it may occur in any kind of transplant and at any time. The course of infection resembles that of the general population, with life-threatening infectious complications, but good response to ART. Assessment of lifestyle and risk behavior is paramount, as indications may be not disclosed without direct questioning.


Assuntos
Antivirais/uso terapêutico , Infecções por HIV/epidemiologia , Transplante de Coração/efeitos adversos , Transplante de Rim/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Adulto , Feminino , Seguimentos , Rejeição de Enxerto/prevenção & controle , HIV/efeitos dos fármacos , HIV/isolamento & purificação , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Comportamentos de Risco à Saúde , Humanos , Imunossupressores/uso terapêutico , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/virologia , Resposta Viral Sustentada
19.
Phys Chem Chem Phys ; 20(28): 19045-19056, 2018 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-29972185

RESUMO

Typical direct liquid fuel cells (DLFCs) use a liquid fuel and O2 as the oxidant. However, for applications where O2 is not available (e.g., space and underwater), the gas has been replaced by H2O2 as a liquid oxidant. This work presents a study of various ceramic disc electrodes with K2NiO4 structure and nominal compositions La2NiO4, La2CuO4, La1.9Pr0.1CuO4, La1.9Sr0.1CuO4, La1.8Ce0.2NiO4, La1.9Pr0.1NiO4, La1.8Pr0.2NiO4 and La1.9Sr0.1NiO4 to assess their stability and activity for the hydrogen peroxide reduction reaction (HPRR) in alkaline media. Stability tests conducted in 2 M NaOH show that Ni and Cu are readily dissolved, as occurs for substituting elements such as Sr, in agreement with calculated Pourbaix diagrams. Such degradation affects the surface of the materials, which is depleted of transition metals. This has consequences for the ORR and HPRR activity due to formation of a La-rich passivation layer on the surface. Only La2CuO4 and La1.8Ce0.2NiO4 display HPRR activity at around -0.25 V vs. RHE. An attempt is made to correlate the composition, chemical stability and electrochemical behaviour of these materials based on known molecular-orbital models proposed for the oxygen reduction reaction.

20.
Am J Hum Biol ; 30(1)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28925585

RESUMO

OBJECTIVES: To investigate the relationships of biological, behavioral, familial, and environmental characteristics with siblings´ physical activity (PA) levels as well as the intrapair resemblance in PA. METHODS: The sample comprises 834 (390 females) biological siblings [brother-brother (BB), sister-sister (SS), brother-sister (BS)] aged 9 to 20 years. Total PA index (TPAI) was estimated by questionnaire. Information on potential behavioral, familial, and environmental correlates was obtained by self-report; body mass index (BMI), biological maturation, and physical fitness were measured. Multilevel models were used to analyze siblings´ clustered data, and sibling resemblance was estimated with the intraclass correlation (ρ). RESULTS: On average, younger sibs, those more physically fit, and those with more parental support had greater TPAI. Further, BB pairs had higher TPAI levels than SS or BS pairs, but also had greater within-pair variance. When adjusted for all covariates, SS pairs demonstrated greater resemblance in TPAI (ρ = 0.53, 95%CI = 0.38-0.68) than BS (ρ = 0.26, 95%CI = 0.14-0.43) or BB pairs (ρ = 0.18, 95%CI = 0.06-0.44). CONCLUSIONS: Age, physical fitness, and parental support were the best predictors of TPAI levels. A moderate level of resemblance in TPAI was observed in SS pairs, while lower resemblance was found for BS and BB pairs. These findings may be due to differences in the roles of shared genetic factors, familial, and environmental characteristics across different sibling types.


Assuntos
Exercício Físico , Crescimento , Nível de Saúde , Estilo de Vida , Aptidão Física , Irmãos , Adolescente , Criança , Feminino , Humanos , Masculino , Portugal , Adulto Jovem
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