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1.
Neuroimage ; 225: 117431, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33045336

RESUMO

The identification of community structure in graphs continues to attract great interest in several fields. Network neuroscience is particularly concerned with this problem considering the key roles communities play in brain processes and functionality. Most methods used for community detection in brain graphs are based on the maximization of a parameter-dependent modularity function that often obscures the physical meaning and hierarchical organization of the partitions of network nodes. In this work, we present a new method able to detect communities at different scales in a natural, unrestricted way. First, to obtain an estimation of the information flow in the network we release random walkers to freely move over it. The activity of the walkers is separated into oscillatory modes by using empirical mode decomposition. After grouping nodes by their co-occurrence at each time scale, k-modes clustering returns the desired partitions. Our algorithm was first tested on benchmark graphs with favorable performance. Next, it was applied to real and simulated anatomical and/or functional connectomes in the macaque and human brains. We found a clear hierarchical repertoire of community structures in both the anatomical and the functional networks. The observed partitions range from the evident division in two hemispheres -in which all processes are managed globally- to specialized communities seemingly shaped by physical proximity and shared function. Additionally, the spatial scales of a network's community structure (characterized by a measure we term within-communities path length) appear inversely proportional to the oscillatory modes' average frequencies. The proportionality constant may constitute a network-specific propagation velocity for the information flow. Our results stimulate the research of hierarchical community organization in terms of temporal scales of information flow in the brain network.


Assuntos
Encéfalo/fisiologia , Vias Neurais/fisiologia , Algoritmos , Análise por Conglomerados , Humanos
2.
BMC Health Serv Res ; 20(1): 344, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321489

RESUMO

BACKGROUND: to understand if patients seen at Centro Hospitalar Psiquiátrico de Lisboa (CHPL) live in geographical clusters or randomly throughout the city, as well as determine their access to the psychiatric hospital and primary care facilities (PCF). METHODS: spatial autocorrelation statistics were performed (queen criterion of contiguity), regarding all patients observed at CHPL in 2017 (at the census subsection level), and considering not only their overall number but also main diagnosis, and admission to the psychiatric ward - voluntary or compulsory. Distance to the hospital and to the closest PCF was measured (for each patient and the variables cited above), and the mean values were compared. Finally, the total number of patients around each PCF was counted, considering specified radius sizes of 656 and 1000 m. RESULTS: All 5161 patients (509 psychiatric admissions) were geolocated, and statistical significance regarding patient clustering was found for the total number (p-0.0001) and specific group of disorders, namely Schizophrenia and related disorders (p-0.007) and depressive disorders (p-0.0002). Patients who were admitted in a psychiatric ward live farther away from the hospital (p-0.002), with the compulsory admissions (versus voluntary ones) living even farther (p-0.004). Furthermore, defining a radius of 1000 m for each PCF allowed the identification of two PCF with more than 1000 patients, and two others with more than 800. CONCLUSIONS: as patients seem to live in geographical clusters (and considering PCFs with the highest number of them), possible locations for the development of programs regarding mental health treatment and prevention can now be identified.


Assuntos
Serviços Comunitários de Saúde Mental , Acessibilidade aos Serviços de Saúde , Atenção Primária à Saúde , Adulto , Feminino , Hospitalização/estatística & dados numéricos , Hospitais Psiquiátricos/estatística & dados numéricos , Humanos , Masculino , Transtornos Mentais/epidemiologia , Transtornos Mentais/terapia , Portugal/epidemiologia , Estudos Retrospectivos , Análise Espacial
3.
Mol Phylogenet Evol ; 141: 106605, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31479732

RESUMO

The origin of the mammalian order Eulipotyphla has been debated intensively with arguments around whether they began diversifying before or after the Cretaceous-Palaeogene (K-Pg) boundary at 66 Ma. Here, we used an in-solution nucleotide capture method and next generation DNA sequencing to determine the sequence of hundreds of ultra-conserved elements (UCEs), and conducted phylogenomic and molecular dating analyses for the four extant eulipotyphlan lineages-Erinaceidae, Solenodontidae, Soricidae, and Talpidae. Concatenated maximum-likelihood analyses with single or partitioned models and a coalescent species-tree analysis showed that divergences among the four major eulipotyphlan lineages occurred within a short period of evolutionary time, but did not resolve the interrelationships among them. Alternative suboptimal phylogenetic hypotheses received consistently the same amount of support from different UCE loci, and were not significantly different from the maximum likelihood tree topology, suggesting the prevalence of stochastic lineage sorting. Molecular dating analyses that incorporated among-lineage evolutionary rate differences supported a scenario where the four eulipotyphlan families diversified between 57.8 and 63.2 Ma. Given short branch lengths with low support values, traces of rampant genome-wide stochastic lineage sorting, and post K-Pg diversification, we concluded that the crown eulipotyphlan lineages arose through a rapid diversification after the K-Pg boundary when novel niches were created by the mass extinction of species.


Assuntos
Sequência Conservada , Mamíferos/classificação , Mamíferos/genética , Filogenia , Animais , Composição de Bases/genética , Calibragem , Sequência Conservada/genética , Variação Genética , Funções Verossimilhança , Fatores de Tempo
4.
PLoS Comput Biol ; 14(5): e1006136, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29795548

RESUMO

Brain stimulation can modulate the activity of neural circuits impaired by Alzheimer's disease (AD), having promising clinical benefit. However, all individuals with the same condition currently receive identical brain stimulation, with limited theoretical basis for this generic approach. In this study, we introduce a control theory framework for obtaining exogenous signals that revert pathological electroencephalographic activity in AD at a minimal energetic cost, while reflecting patients' biological variability. We used anatomical networks obtained from diffusion magnetic resonance images acquired by the Alzheimer's Disease Neuroimaging Initiative (ADNI) as mediators for the interaction between Duffing oscillators. The nonlinear nature of the brain dynamics is preserved, given that we extend the so-called state-dependent Riccati equation control to reflect the stimulation objective in the high-dimensional neural system. By considering nonlinearities in our model, we identified regions for which control inputs fail to correct abnormal activity. There are changes to the way stimulated regions are ranked in terms of the energetic cost of controlling the entire network, from a linear to a nonlinear approach. We also found that limbic system and basal ganglia structures constitute the top target locations for stimulation in AD. Patients with highly integrated anatomical networks-namely, networks having low average shortest path length, high global efficiency-are the most suitable candidates for the propagation of stimuli and consequent success on the control task. Other diseases associated with alterations in brain dynamics and the self-control mechanisms of the brain can be addressed through our framework.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Encéfalo , Imagem de Difusão por Ressonância Magnética/métodos , Eletroencefalografia/métodos , Neuroimagem/métodos , Algoritmos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Simulação por Computador , Humanos , Processamento de Imagem Assistida por Computador , Dinâmica não Linear , Processamento de Sinais Assistido por Computador
5.
Malar J ; 17(1): 177, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29743113

RESUMO

BACKGROUND: Increased susceptibility to malaria during pregnancy is not completely understood. Cellular immune responses mediate both pathology and immunity but the effector responses involved in these processes have not been fully characterized. Maternal and fetal cytokine and chemokine responses to malaria at delivery, and their association with pregnancy and childhood outcomes, were investigated in 174 samples from a mother and child cohort from Mozambique. Peripheral and cord mononuclear cells were stimulated with Plasmodium falciparum lysate and secretion of IL-12p70, IFN-γ, IL-2, IL-10, IL-8, IL-6, IL-4, IL-5, IL-1ß, TNF, TNF-ß was quantified in culture supernatants by multiplex flow cytometry while cellular mRNA expression of IFN-γ, TNF, IL-2, IL-4, IL-6, IL-10 and IL-13 was measured by quantitative PCR. RESULTS: Higher concentrations of IL-6 and IL-1ß were associated with a reduced risk of P. falciparum infection in pregnant women (p < 0.049). Pro-inflammatory cytokines IL-6, IL-1ß and TNF strongly correlated among themselves (ρ > 0.5, p < 0.001). Higher production of IL-1ß was significantly associated with congenital malaria (p < 0.046) and excessive TNF was associated with peripheral infection and placental lesions (p < 0.044). CONCLUSIONS: Complex network of immuno-pathological cytokine mechanisms in the placental and utero environments showed a potential trade-off between positive and negative effects on mother and newborn susceptibility to infection.


Assuntos
Citocinas/imunologia , Sangue Fetal/parasitologia , Imunidade Celular , Leucócitos Mononucleares/imunologia , Malária Falciparum/imunologia , Complicações Parasitárias na Gravidez/imunologia , Adolescente , Adulto , Estudos de Coortes , Citocinas/sangue , Feminino , Humanos , Lactente , Recém-Nascido , Malária Falciparum/parasitologia , Moçambique , Plasmodium falciparum/fisiologia , Gravidez , Complicações Parasitárias na Gravidez/parasitologia , Adulto Jovem
6.
Malar J ; 17(1): 182, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29743114

RESUMO

BACKGROUND: Difficulties to disentangle the protective versus exposure role of anti-malarial antibodies hamper the identification of clinically-relevant immune targets. Here, factors affecting maternal IgG and IgMs against Plasmodium falciparum antigens, as well as their relationship with parasite infection and clinical outcomes, were assessed in mothers and their children. Antibody responses among 207 Mozambican pregnant women at delivery against MSP119, EBA175, AMA1, DBLα and parasite lysate (3D7, R29 and E8B parasite lines), as well as the surface of infected erythrocytes, were assessed by enzyme-linked immunosorbent assay and flow cytometry. The relationship between antibody levels, maternal infection and clinical outcomes was assessed by multivariate regression analysis. RESULTS: Placental infection was associated with an increase in maternal levels of IgGs and IgMs against a broad range of parasite antigens. The multivariate analysis including IgGs and IgMs showed that the newborn weight increased with increasing IgG levels against a parasite lysate, whereas the opposite association was found with IgMs. IgGs are markers of protection against poor pregnancy outcomes and IgMs of parasite exposure. CONCLUSIONS: Adjusting the analysis for the simultaneous effect of IgMs and IgGs can contribute to account for heterogeneous exposure to P. falciparum when assessing immune responses effective against malaria in pregnancy.


Assuntos
Imunoglobulina G/metabolismo , Imunoglobulina M/metabolismo , Malária Falciparum/diagnóstico , Plasmodium falciparum/imunologia , Complicações Parasitárias na Gravidez/diagnóstico , Adolescente , Adulto , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Malária Falciparum/prevenção & controle , Moçambique/epidemiologia , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/parasitologia , Complicações Parasitárias na Gravidez/prevenção & controle , Prevalência , Adulto Jovem
7.
J Investig Allergol Clin Immunol ; 28(6): 379-391, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30004024

RESUMO

Atopic dermatitis (AD) is a recurrent and chronic skin disease characterized by dysfunction of the epithelial barrier, skin inflammation, and immune dysregulation, with changes in the skin microbiota and colonization by Staphylococcus aureus being common. For this reason, the therapeutic approach to AD is complex and should be directed at restoring skin barrier function, reducing dehydration, maintaining acidic pH, and avoiding superinfection and exposure to possible allergens. There is no curative treatment for AD. However, a series of measures are recommended to alleviate the disease and enable patients to improve their quality of life. These include adequate skin hydration and restoration of the skin barrier with the use of emollients, antibacterial measures, specific approaches to reduce pruritus and scratching, wet wrap applications, avoidance of typical AD triggers, and topical anti-inflammatory drugs. Anti-inflammatory treatment is generally recommended during acute flares or, more recently, for preventive management. Nevertheless, the selection of the pharmacologic agent, as well as its potency, duration, and frequency of application must be in accordance with the severity of the disease and the distribution and type of the lesion. The objectives of this review are to emphasize the importance of basic skin care and to describe current and novel topical therapies for AD.


Assuntos
Dermatite Atópica/tratamento farmacológico , Pele/efeitos dos fármacos , Animais , Humanos , Qualidade de Vida , Higiene da Pele/métodos
8.
BMC Med Educ ; 18(1): 68, 2018 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-29622041

RESUMO

BACKGROUND: Misconduct during medical school predicts subsequent fitness to practise (FtP) events in doctors, but relatively little is known about which factors are associated with such issues during undergraduate education. This study exploits the newly created UK medical education database (UKMED), with the aim of identifying predictors of conduct or health-related issues that could potentially impair FtP. The findings would have implications for policies related to both the selection and support of medical students. METHODS: Data were available for 14,379 students obtaining provisional registration with the General Medical Council who started medical school in 2007 and 2008. FtP declarations made by students were available, as were various educational and demographic predictor variables, including self-report 'personality measures' for students who participated in UK Clinical Aptitude Test (UKCAT) pilot studies. Univariable and multivariable logistic regression models were developed to evaluate the predictors of FtP declarations. RESULTS: Significant univariable predictors (p < 0.05) for conduct-related declarations included male gender, white ethnicity and a non-professional parental background. Male gender (OR 3.07) and higher 'self-esteem' (OR 1.45) were independently associated with an increased risk of a conduct issue. Female gender, a non-professional background, and lower self-reported 'confidence' were, among others, associated with increased odds of a health-related declaration. Only 'confidence' was a significant independent predictor of a health declaration (OR 0.69). Female gender, higher UKCAT score, a non-professional background and lower 'confidence' scores were significant predictors of reported depression, and the latter two variables were independent predictors of declared depression. CONCLUSIONS: White ethnicity and UK nationality were associated with increased odds of both conduct and health-related declarations, as were certain personality traits. Students from non-professional backgrounds may be at increased risk of depression and therefore could benefit from targeted support. The small effect sizes observed for the 'personality measures' suggest they would offer little potential benefit for selection, over and above those measures already in use.


Assuntos
Competência Clínica , Educação de Graduação em Medicina , Inabilitação do Médico , Má Conduta Profissional , Estudantes de Medicina , Análise de Variância , Bases de Dados Factuais , Escolaridade , Feminino , Previsões , Humanos , Masculino , Pais/educação , Personalidade , Projetos Piloto , Faculdades de Medicina , Autoimagem , Fatores Sexuais , Reino Unido , População Branca
9.
BMC Med ; 15(1): 66, 2017 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-28316280

RESUMO

BACKGROUND: International medical graduates working in the UK are more likely to be censured in relation to fitness to practise compared to home graduates. Performance on the General Medical Council's (GMC's) Professional and Linguistic Assessments Board (PLAB) tests and English fluency have previously been shown to predict later educational performance in this group of doctors. It is unknown whether the PLAB system is also a valid predictor of unprofessional behaviour and malpractice. The findings would have implications for regulatory policy. METHODS: This was an observational study linking data relating to fitness to practise events (referral or censure), PLAB performance, demographic variables and English language competence, as evaluated via the International English Language Test System (IELTS). Data from 27,330 international medical graduates registered with the GMC were analysed, including 210 doctors who had been sanctioned in relation to at least one fitness to practise issue. The main outcome was risk of eventual censure (including a warning). RESULTS: The significant univariable educational predictors of eventual censure (versus no censures or referrals) were lower PLAB part 1 (hazard ratio [HR], 0.99; 95% confidence interval, 0.98 to 1.00) and part 2 scores (HR, 0.94; 0.91 to 0.97) at first sitting, multiple attempts at both parts of the PLAB, lower IELTS reading (HR, 0.79; 0.65 to 0.94) and listening scores (HR, 0.76; 0.62 to 0.93) and higher IELTS speaking scores (HR, 1.28; 1.04 to 1.57). Multiple resits at either part of the PLAB and higher IELTS speaking score (HR, 1.49; 1.20 to 1.84) were also independent predictors of censure. We estimated that the proposed limit of four attempts at both parts of the PLAB would reduce the risk in this entire group by only approximately two censures per 5 years in this group of doctors. CONCLUSIONS: Making the PLAB, or any replacement assessment, more stringent and raising the required standards of English reading and listening may result in fewer fitness to practice events in international medical graduates. However, the number of PLAB resits permitted would have to be further capped to meaningfully impact the risk of sanctions in this group of doctors.


Assuntos
Certificação/normas , Competência Clínica/normas , Emigrantes e Imigrantes , Médicos/normas , Má Conduta Profissional/estatística & dados numéricos , Estudos de Coortes , Feminino , Humanos , Linguística , Masculino
10.
BMC Med ; 14(1): 140, 2016 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-27638740

RESUMO

BACKGROUND: The UK Clinical Aptitude Test (UKCAT) has been shown to have a modest but statistically significant ability to predict aspects of academic performance throughout medical school. Previously, this ability has been shown to be incremental to conventional measures of educational performance for the first year of medical school. This study evaluates whether this predictive ability extends throughout the whole of undergraduate medical study and explores the potential impact of using the test as a selection screening tool. METHODS: This was an observational prospective study, linking UKCAT scores, prior educational attainment and sociodemographic variables with subsequent academic outcomes during the 5 years of UK medical undergraduate training. The participants were 6812 entrants to UK medical schools in 2007-8 using the UKCAT. The main outcome was academic performance at each year of medical school. A receiver operating characteristic (ROC) curve analysis was also conducted, treating the UKCAT as a screening test for a negative academic outcome (failing at least 1 year at first attempt). RESULTS: All four of the UKCAT scale scores significantly predicted performance in theory- and skills-based exams. After adjustment for prior educational achievement, the UKCAT scale scores remained significantly predictive for most years. Findings from the ROC analysis suggested that, if used as a sole screening test, with the mean applicant UKCAT score as the cut-off, the test could be used to reject candidates at high risk of failing at least 1 year at first attempt. However, the 'number needed to reject' value would be high (at 1.18), with roughly one candidate who would have been likely to pass all years at first sitting being rejected for every higher risk candidate potentially declined entry on this basis. CONCLUSIONS: The UKCAT scores demonstrate a statistically significant but modest degree of incremental predictive validity throughout undergraduate training. Whilst the UKCAT could be considered a fairly crude screening tool for future academic performance, it may offer added value when used in conjunction with other selection measures. Future work should focus on the optimum role of such tests within the selection process and the prediction of post-graduate performance.


Assuntos
Testes de Aptidão/normas , Competência Clínica/normas , Educação de Graduação em Medicina/normas , Avaliação Educacional/normas , Estudantes de Medicina , Estudos de Coortes , Educação de Graduação em Medicina/métodos , Avaliação Educacional/métodos , Feminino , Previsões , Humanos , Masculino , Estudos Prospectivos , Reprodutibilidade dos Testes , Critérios de Admissão Escolar , Faculdades de Medicina/normas , Reino Unido/epidemiologia
11.
J Exp Zool B Mol Dev Evol ; 324(5): 410-23, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26055630

RESUMO

The divergent evolution of niche-related traits can facilitate adaptive radiation, yet identification of the genetic or molecular mechanisms underlying such trait changes remains a major challenge in evolutionary biology. Conducting a detailed morphological comparison along growth trajectories is a powerful method for observing the formation of differences in niche-related traits. Here, we focused on hindlimb length of Anolis lizards, differences in which are related to adaptation for use of different microhabitats. We measured the length of hindlimb skeletons in different ecomorphs of anole lizards (A. sagrei, a trunk-ground ecomorph with long hindlimbs, and A. angusticeps, a twig ecomorph with short hindlimbs) from early embryonic stages to adulthood, to determine which hindlimb elements mainly differentiate the species and the timing of the formation of these differences. With respect to the digit, differences between the species mainly occurred during the embryonic stages of interdigit reduction, when the cartilage of the distal phalanges was simultaneously forming. In addition, we compared the relative length of developing autopods in early embryonic stages using whole-mount in situ hybridization before the formation of the cartilaginous bones, and the results showed that the relative growth rate of the Hoxa11-negative distal region in A. sagrei was greater than that in A. angusticeps. Our results show that there are several important developmental stages for hindlimb length differentiation between A. angusticeps and A. sagrei, depending on which hindlimb element is considered. In particular, the species differences were largely due to variations in digit length, which arose at early embryonic stages.


Assuntos
Lagartos/embriologia , Lagartos/crescimento & desenvolvimento , Animais , Evolução Biológica , Desenvolvimento Ósseo , Osso e Ossos/embriologia , Ecossistema , Membro Posterior/embriologia , Membro Posterior/crescimento & desenvolvimento , Lagartos/genética , Masculino , Especificidade da Espécie
12.
Rheumatol Int ; 35(1): 107-14, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24948375

RESUMO

To determine the prevalence of and associated factors to work instability (WI) in rheumatoid arthritis (RA) Argentinean patients. Observational cross-sectional study that assessing employment status in currently working RA patients. They answered the validated version of RA work instability scale (RA-WIS). High-risk WI was considered when RA-WIS was ≥17. Factors associated with high-risk WI were examined by univariable and multivariable analysis. Four-hundred and fifty RA patients were enrolled; of these, 205 patients were currently employed, but only 172 have completed questionnaires required [RA-WIS and health assessment questionnaire (HAQ-A)]. Their mean age was 49.3 ± 10.8 years; 81.3 % were female; and their mean disease duration was 8.1 ± 7.2 years. Fifty-two percent of patients were doing manual work. The mean RA-WIS score was 11.4 ± 6.8, and 41 % of patients had a high-risk WI. High-risk WI was associated with radiographic erosions (p < 0.001) and HAQ-A >0.87 (p < 0.001) in the univariable analysis, whereas in the multivariable logistic regression analysis the variables associated with a high-risk WI were as follows: HAQ-A >0.87 [odds ratio (OR) 12.31; 95 % CI 5.38-28.18] and the presence of radiographic erosions (OR 4.848; 95 % CI 2.22-10.5). In this model, having a higher monthly income (OR 0.301; 95 % CI 0.096-0.943) and a better functional class (OR 0.151; 95 % CI 0.036-0.632) were protective. Forty-one percent of RA working patients had high-risk WI. The predictors of high RA-WIS were HAQ-A ≥0.87 and radiographic erosions, whereas having a better functional class and have higher incomes were protective.


Assuntos
Artrite Reumatoide , Avaliação da Deficiência , Emprego , Adulto , Argentina , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Inquéritos e Questionários
13.
Allergy ; 69(12): 1610-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25123397

RESUMO

BACKGROUND: Profilins are ubiquitous proteins that act as panallergens in sensitized patients, considered to be mild or incomplete food allergens. The aim of the study was to evaluate the role of profilins as severe food allergens in allergic patients overexposed to grass who were referred for severe food reactions and were sensitized to profilins. METHODS: After a careful in vitro screening, 26 patients were included, classified into two groups, mild (17) and severe reactors (9), based on clinical history and subsequently provoked orally with purified profilin in a double-blind placebo-controlled food challenge setup. RESULTS: A significant number of patients presented severe positive food challenge test reactions at low doses of the allergen profilin. Patients prone to suffer from severe reactions had lower IgG4/IgE ratio to major grass allergens than those who did not. CONCLUSION: Profilins are complete food allergens in food-allergic patient populations that are exposed to high levels of grass pollen. This type of patient constitutes an optimal model to understand the link between respiratory and food allergies. The nature of the observed reactions and the low level of allergen eliciting the reactions suggest that intake through the oral mucosa might constitute a relevant route of exposure to food allergens.


Assuntos
Alérgenos/imunologia , Hipersensibilidade/imunologia , Poaceae/efeitos adversos , Pólen/imunologia , Profilinas/imunologia , Adolescente , Adulto , Alérgenos/administração & dosagem , Citrus sinensis/efeitos adversos , Cucurbitaceae/efeitos adversos , Feminino , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/imunologia , Humanos , Hipersensibilidade/diagnóstico , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Solanum lycopersicum/efeitos adversos , Masculino , Pessoa de Meia-Idade , Testes Cutâneos , Adulto Jovem
14.
J Dairy Sci ; 97(9): 5393-400, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24996276

RESUMO

Use of DNA-based methods, such as real-time PCR, has increased the sensitivity and shortened the time for bacterial identification, compared with traditional bacteriology; however, results should be interpreted carefully because a positive PCR result does not necessarily mean that an infection exists. One hundred eight lactating dairy ewes (56 Manchega and 52 Lacaune) and 24 Murciano-Granadina dairy goats were used for identifying the main bacteria causing intramammary infections (IMI) using traditional bacterial culturing and real-time PCR and their effects on milk performance. Udder-half milk samples were taken for bacterial culturing and somatic cell count (SCC) 3 times throughout lactation. Intramammary infections were assessed based on bacteria isolated in ≥2 samplings accompanied by increased SCC. Prevalence of subclinical IMI was 42.9% in Manchega and 50.0% in Lacaune ewes and 41.7% in goats, with the estimated milk yield loss being 13.1, 17.9, and 18.0%, respectively. According to bacteriology results, 87% of the identified single bacteria species (with more than 3 colonies/plate) or culture-negative growth were identical throughout samplings, which agreed 98.9% with the PCR results. Nevertheless, the study emphasized that 1 sampling may not be sufficient to determine IMI and, therefore, other inflammatory responses such as increased SCC should be monitored to identify true infections. Moreover, when PCR methodology is used, aseptic and precise milk sampling procedures are key for avoiding false-positive amplifications. In conclusion, both PCR and bacterial culture methods proved to have similar accuracy for identifying infective bacteria in sheep and goats. The final choice will depend on their response time and cost analysis, according to the requirements and farm management strategy.


Assuntos
Infecções Assintomáticas/epidemiologia , Cabras/microbiologia , Mastite/veterinária , Leite/microbiologia , Ovinos/microbiologia , Animais , Contagem de Células/veterinária , Contagem de Colônia Microbiana , Feminino , Lactação , Glândulas Mamárias Animais/microbiologia , Mastite/epidemiologia , Leite/citologia , Prevalência , Reação em Cadeia da Polimerase em Tempo Real
15.
Colloids Surf B Biointerfaces ; 234: 113722, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38160473

RESUMO

Biomimetic magnetic nanoparticles (BMNPs) mediated by MamC have proven to be photothermal agents able to allow an optimized cytotoxicity against tumoral cells when used simultaneously as drug nanotransporters and as hyperthermia agents. However, it remains unclear whether BMNPs need to be internalized by the cells and/or if there is a threshold for internal Fe concentration for the photothermal therapy to be effective. In this study, three different situations for photothermal treatments have been simulated to disentangle the effect of BMNPs cell uptake on cell viability after photothermal treatments. Human hepatoblastoma (HepG2) cell line was treated with suspensions of BMNPs, and protocols were developed to have only intracellular BMNPs, only extracellular BMNPs or both, followed by photothermal exposure of the treated cell cultures. Our data demonstrate that: (1) Although the heating efficiency of the photothermal agent is not altered by its location (intra/extracellular), the intracellular location of BMNPs is crucial to ensure the cytotoxic effect of photothermal treatments, especially at low Fe concentration. In fact, the concentration of BMNPs needed to reach the same cytotoxic effect following upon laser irradiation of 0.2 W/cm2 is three times larger if BMNPs are located extracellularly compared to that needed if BMNPs are located intracellularly; (2) For a given location of the BMNPs, cell death increases with BMNPs (or Fe) concentration. When BMNPs are located intracellularly, there is a threshold for Fe concentration (∼ 0.5 mM at laser power intensities of 0.1 W/cm2) needed to affect cell viability following upon cell exposure to photothermia. (3) Bulk temperature rise is not the only factor accounting for cell death. Actually, temperature increases inside the cells cause more damage to cell structures and trigger cell death more efficiently than an increase in the temperature outside the cell.


Assuntos
Hipertermia Induzida , Nanopartículas de Magnetita , Nanopartículas , Humanos , Hipertermia Induzida/métodos , Nanopartículas de Magnetita/química , Biomimética , Linhagem Celular Tumoral , Fototerapia/métodos
16.
Updates Surg ; 76(3): 1091-1097, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38489129

RESUMO

INTRODUCTION: During the surge of the SARS-CoV-2 pandemic, studies revealed high complication and morbidity rates following surgical procedures in COVID-19 positive patients. Anesthetic and surgical societies swiftly developed strategies to mitigate these risks, including a recommended postponement of elective surgeries for a minimum of 7 weeks post-COVID infection. Nowadays, with a predominantly vaccinated population, it has become crucial to discern the influencing factors on post-COVID morbidity and mortality and a reevaluation of the existing recommendations pertaining to elective surgery. METHODS: A single-center case-control study was conducted, including patients who underwent surgery between November 2021 and March 2022 and met the inclusion criteria. Eighty COVID-19 positive patients were matched 1:1 with 80 controls, each undergoing an identical intervention within a 2-week time frame. The primary outcome was 30-day postoperative mortality and secondary outcome postoperative complications (respiratory and thromboembolic). RESULTS: At the time of surgery, 88.8% of patients in the case group and 92.5% in the control group had received at least one vaccine dose. Mortality and morbidity did not show a significant difference when comparing the case and control groups (7.5% vs 6.2%, p = 0.755; 11.3% vs 8.9%, p = 0.541 respectively). In the COVID-positive group, mortality was significantly associated with age over 70 years, ASA score over III, RCRI over 1, emergency procedures, and absence of thromboembolic prophylaxis. CONCLUSIONS: In contrast to previously reported findings, we did not observe an increased morbi-mortality in patients with perioperative COVID-19 infection. It may not be necessary to delay elective interventions, except in cases with a high-risk.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Procedimentos Cirúrgicos Eletivos , Complicações Pós-Operatórias , Humanos , COVID-19/prevenção & controle , COVID-19/epidemiologia , Estudos de Casos e Controles , Masculino , Feminino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Idoso , Vacinas contra COVID-19/administração & dosagem , Vacinação , Adulto , Idoso de 80 Anos ou mais
17.
Commun Biol ; 7(1): 528, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704445

RESUMO

Neuronal dysfunction and cognitive deterioration in Alzheimer's disease (AD) are likely caused by multiple pathophysiological factors. However, mechanistic evidence in humans remains scarce, requiring improved non-invasive techniques and integrative models. We introduce personalized AD computational models built on whole-brain Wilson-Cowan oscillators and incorporating resting-state functional MRI, amyloid-ß (Aß) and tau-PET from 132 individuals in the AD spectrum to evaluate the direct impact of toxic protein deposition on neuronal activity. This subject-specific approach uncovers key patho-mechanistic interactions, including synergistic Aß and tau effects on cognitive impairment and neuronal excitability increases with disease progression. The data-derived neuronal excitability values strongly predict clinically relevant AD plasma biomarker concentrations (p-tau217, p-tau231, p-tau181, GFAP) and grey matter atrophy obtained through voxel-based morphometry. Furthermore, reconstructed EEG proxy quantities show the hallmark AD electrophysiological alterations (theta band activity enhancement and alpha reductions) which occur with Aß-positivity and after limbic tau involvement. Microglial activation influences on neuronal activity are less definitive, potentially due to neuroimaging limitations in mapping neuroprotective vs detrimental activation phenotypes. Mechanistic brain activity models can further clarify intricate neurodegenerative processes and accelerate preventive/treatment interventions.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Encéfalo , Proteínas tau , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Humanos , Proteínas tau/metabolismo , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Masculino , Feminino , Idoso , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Modelos Neurológicos , Biomarcadores/sangue , Idoso de 80 Anos ou mais , Eletroencefalografia , Neurônios/metabolismo
18.
NPJ Vaccines ; 9(1): 5, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38177171

RESUMO

Schistosomiasis, a challenging neglected tropical disease, affects millions of people worldwide. Developing a prophylactic vaccine against Schistosoma mansoni has been hindered by the parasite's biological complexity. In this study, we utilized the innovative phage-display immunoprecipitation followed by a sequencing approach (PhIP-Seq) to screen the immune response of 10 infected rhesus macaques during self-cure and challenge-resistant phases, identifying vaccine candidates. Our high-throughput S. mansoni synthetic DNA phage-display library encoded 99.6% of 119,747 58-mer peptides, providing comprehensive coverage of the parasite's proteome. Library screening with rhesus macaques' antibodies, from the early phase of establishment of parasite infection, identified significantly enriched epitopes of parasite extracellular proteins known to be expressed in the digestive tract, shifting towards intracellular proteins during the late phase of parasite clearance. Immunization of mice with a selected pool of PhIP-Seq-enriched phage-displayed peptides from MEG proteins, cathepsins B, and asparaginyl endopeptidase significantly reduced worm burden in a vaccination assay. These findings enhance our understanding of parasite-host immune responses and provide promising prospects for developing an effective schistosomiasis vaccine.

20.
bioRxiv ; 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37502947

RESUMO

Neuronal dysfunction and cognitive deterioration in Alzheimer's disease (AD) are likely caused by multiple pathophysiological factors. However, evidence in humans remains scarce, necessitating improved non-invasive techniques and integrative mechanistic models. Here, we introduce personalized brain activity models incorporating functional MRI, amyloid-ß (Aß) and tau-PET from AD-related participants (N=132). Within the model assumptions, electrophysiological activity is mediated by toxic protein deposition. Our integrative subject-specific approach uncovers key patho-mechanistic interactions, including synergistic Aß and tau effects on cognitive impairment and neuronal excitability increases with disease progression. The data-derived neuronal excitability values strongly predict clinically relevant AD plasma biomarker concentrations (p-tau217, p-tau231, p-tau181, GFAP). Furthermore, our results reproduce hallmark AD electrophysiological alterations (theta band activity enhancement and alpha reductions) which occur with Aß-positivity and after limbic tau involvement. Microglial activation influences on neuronal activity are less definitive, potentially due to neuroimaging limitations in mapping neuroprotective vs detrimental phenotypes. Mechanistic brain activity models can further clarify intricate neurodegenerative processes and accelerate preventive/treatment interventions.

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