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1.
Toxicol Sci ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38754108

RESUMO

Although iron (Fe) is the most biologically abundant transition metal, it is highly toxic when it accumulates as Fe2+, forming a labile Fe pool and favoring the Fenton reaction. This oxidative scenario leads to a type of caspase-independent programmed cell death, referred to as ferroptosis, where following processes take place: 1) Fe2+ overload; 2) glutathione peroxidase 4 inactivation; 3) lipid peroxidation and 4) glutathione depletion. The present study sought to evaluate the consequences of Fe2+ administration on ferroptosis induction in Caenorhabditis elegans. We demonstrated higher mortality, increased lipid peroxidation, reduced glutathione peroxidase activity, and morphological damage in dopaminergic neurons upon Fe2+ overload. Pharmacological intervention at the level of lipid peroxidation with ferrostatin-1 (250 µM) mitigated the damage and returned the biochemical parameters to basal levels, revealing the potential of this therapeutical approach. Finally, to assess the relationship between ferroptosis and dopamine in a Parkinsonian background, we evaluated the UA44 worm strain which overexpresses the alpha-synuclein protein in cherry-labeled dopaminergic neurons. We demonstrated that Fe2+ administration reduced lethality associated with similar alterations in biochemical and dopaminergic morphological parameters in wild-type animals. These experiments provide mechanistic-based evidence on the efficacy of a pharmacological approach to mitigate the physiological, biochemical, and morphological consequences of Fe2+ overload. At the same time, they encourage further research on the impact of the combined effects resulting from the genetic background and dopamine signaling in a Parkinsonian phenotype.

2.
Acta Psychol (Amst) ; 239: 103992, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37536011

RESUMO

Interpersonal coordination of body movement-or similarity in patterning and timing of body movement between interaction partners-is well documented in face-to-face (FTF) conversation. Here, we investigated the degree to which interpersonal coordination is impacted by the amount of visual information available and the type of interaction conversation partners are having. To do so within a naturalistic context, we took advantage of the increased familiarity with videoconferencing (VC) platforms and with limited visual information in FTF conversation due to the COVID-19 pandemic. Pairs of participants communicated in one of three ways: FTF in a laboratory setting while socially distanced and wearing face masks; VC in a laboratory setting with a view of one another's full movements; or VC in a remote setting with a view of one another's face and shoulders. Each pair held three conversations: affiliative, argumentative, and cooperative task-based. We quantified interpersonal coordination as the relationship between the two participants' overall body movement using nonlinear time series analyses. Coordination changed as a function of the contextual constraints, and these constraints interacted with coordination patterns to affect subjective conversation outcomes. Importantly, we found patterns of results that were distinct from previous research; we hypothesize that these differences may be due to changes in the broader social context from COVID-19. Taken together, our results are consistent with a dynamical systems view of social phenomena, with interpersonal coordination emerging from the interaction between components, constraints, and history of the system.


Assuntos
COVID-19 , Relações Interpessoais , Humanos , Pandemias , Comunicação , Comunicação por Videoconferência
3.
Artigo em Inglês | MEDLINE | ID: mdl-37486539

RESUMO

Oxygenic photosynthesis is responsible for most of the fixation of atmospheric CO2. The microalgal community can transport atmospheric carbon into biological cycles in which no additional CO2 is created. This represents a resource to confront the actual climate change crisis. These organisms have evolved to adapt to several environments and different spectral distribution of light that may strongly influence their metabolism. Therefore, there is a need for development of photobioreactors specialized in addressing spectral optimization. Here, a multi-scale modular photobioreactor made from standard glass materials, ad hoc light circuits, and easily accessible, small commercial devices is described. The system is suitable to manage the principal culture variables of research in bioenergetics and photosynthesis. Its performance was tested by growing four evolutionary-distant microalgal species with different endosymbiotic scenarios: Chlamydomonas reinhardtii (Archaeplastida, green primary plastid), Polytomella parva (Archaeplastida, colorless plastid), Euglena gracilis (Discoba, green secondary plastid), and Phaeodactylum tricornutum (Stramenophiles, red secondary plastid). Our results show an improvement of biomass production, as compared to the traditional flask system. The modulation of the incident light spectra allowed us to observe a far-red adaptation in Euglena gracilis with a difference on paramylon production, and it also significantly increased the maximal cell density of the diatom species under green light. Together, these confirm that for photobioreactors with artificial light, manipulation of the light spectrum is a critical parameter for controlling the optimal performance, depending on the downstream goals.

4.
Mar Pollut Bull ; 186: 114419, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36525757

RESUMO

Multivariate analyses have been applied to the REE contents of three cores collected in the Tinto estuary, SW Spain, an extremely polluted area. Results indicate an extremely correlation between all REE, which behave as a single variable. A slight natural pollution peak and three anthropogenic pollution peaks are identified, related with the first mining activities, the Roman period and a recent intensive mining accompanied by a heavy industrial pollution. In all these peaks, the increase of Cu is parallel to that of MREE, which are configured as the best indicators of pollution among REE. Statistical analyses clearly differentiate four groups, each consisting of samples from different environments. Although grain size and this strong pollution alter the study of REE as environmental indicators, it is possible to recognise groups of samples with a common origin or to identify the surface extent of a given pollution peak.


Assuntos
Metais Terras Raras , Poluentes Químicos da Água , Espanha , Estuários , Poluentes Químicos da Água/análise , Metais Terras Raras/análise , Poluição Ambiental/análise , Monitoramento Ambiental/métodos
5.
Drug Alcohol Depend ; 243: 109737, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36535099

RESUMO

BACKGROUND: Ethanol drinking begins during adolescence and, particularly when occurs in a binge-like pattern, exerts lingering adverse consequences. Pre-clinical studies indicate that intermittent ethanol exposure (IEA, a model of repeated ethanol intoxication), or binge eating (BE) can increase subsequent ethanol consumption. It is unknown if the promoting effects of BE upon ethanol drinking are found in female rats and are modulated by IEA at adolescence. This study assessed interactive effects between IEA and BE, upon ethanol drinking. METHODS: Female Wistar rats were given 4.0 g/kg ethanol, every other day from postnatal day 25-45. At adulthood, they were exposed to sessions in which a brief offering of a sizeable portion of highly palatable sugary pills was followed by a 120-min exposure to an ethanol bottle. RESULTS: Exploratory activity and recognition memory was not affected by the IEA. Glutathione peroxidase and catalase activity, and lipid peroxidation (measured in blood and brain at the end of the procedure) were not significantly affected by IEA or BE exposure. BE alone had a mild promoting effect on ethanol ingestion. Those rats that underwent IEA and BE, however, exhibited heightened and sustained ethanol self-administration (average of 2.12 g/kg/120 min, vs 1.15 g/kg/120 min of the other groups), that persisted throughout the BE sessions. IEA and a history of BE also promoted ethanol intake or preference in a two-bottle endpoint test. CONCLUSION: The study suggests that exposure to IEA exerts, when followed by BE at adulthood, promoting effects upon ethanol intake, particularly at concentrations ≥ 6%.


Assuntos
Consumo Excessivo de Bebidas Alcoólicas , Transtorno da Compulsão Alimentar , Ratos , Feminino , Animais , Etanol , Ratos Wistar , Fatores Etários , Consumo de Bebidas Alcoólicas
6.
Neurotoxicol Teratol ; 94: 107131, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36209774

RESUMO

Despite its relative simplicity, the invertebrate Caenorhabditis elegans (C. elegans) has become a powerful tool to evaluate toxicity. Lead (Pb) persistence in the environment and its distinctive characteristic as a neurodevelopmental toxicant determine the potential effects of this metal against challenging events later in life. Additionally, among other psychoactive substances, low to moderate ethanol (EtOH) doses have been pointed out to induce behaviors such as acute functional tolerance (AFT) and drug-induced chemotaxis. In the present study, we aimed to study the impact of early-life Pb exposure on EtOH-induced motivational and stimulant effects in C. elegans by assessing the preference for EtOH and the participation of alcohol dehydrogenase (ADH, sorbitol dehydrogenase -SODH in worms) in the AFT response. Thus, N2 (wild type) and RB2114 (sod-1 -/-) strains developmentally exposed to 24 µM Pb were evaluated in their AFT to 200 mM EtOH alone and in combination with acetaldehyde (ACD). We ascribed the enhanced EtOH-induced AFT observed in the N2 Pb-exposed animals to a reduced ADH functionality as evaluated by both, ADH activity determination and the allyl alcohol test, which altogether suggest excess EtOH accumulation rather than low ACD formation in these animals. Moreover, the Pb-induced preference for EtOH indicates enhanced motivational effects of this drug as a consequence of early-life exposure to Pb, results that resemble our previous reports in rodents and provide a close association between EtOH stimulant and motivational effects in these animals.


Assuntos
Álcool Desidrogenase , Etanol , Animais , Etanol/toxicidade , Álcool Desidrogenase/farmacologia , Caenorhabditis elegans , Chumbo/toxicidade , Acetaldeído/farmacologia
7.
Pain Physician ; 25(6): E831-E840, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36122266

RESUMO

BACKGROUND: Fibromyalgia (FM) is a chronic disease, with no effective treatments for this disorder. The origin is suspected to be a misprocessing of signals in the central nervous system. One of the experimental treatments is very low intensity transcranial magnetic stimulation (LITMS) used to perform central neuromodulation. OBJECTIVES: The main objective was to characterize the differences in oscillatory brain processing before and after LITMS in FM and compare the results with healthy controls. STUDY DESIGN: This is an interventional study with control group, which shows how the treatment with LITMS could modify brain oscillatory activity and be useful for the improvement of symptoms in FM patients. METHODS: Thirty-three women with FM and 14 healthy controls are studied using magnetoencephalography recording, and mechanical stimuli are applied before and after treatment with transcranial magnetic stimulation. Changes in different brain areas and a specific brain frequency are studied, and the results are analyzed within and between patients, before and after treatment. RESULTS: In the FM group, an increase in alpha brain oscillatory activity was observed mainly in the dorsolateral prefrontal cortex (DLPFS), and more pronounced in the left hemisphere (P = 0.03). In addition, there was a significant improvement in the FM impact questionnaire in the patients (P < 0.01). When comparing patients with controls, it is observed that the differences in alpha frequency in this brain area disappear between groups. LIMITATIONS: Age difference between patients and controls. Replicating the long-term results. CONCLUSIONS: This treatment improves the patients' symptomatology, and also produces statistical changes in alpha brain activity in the DLPFS. Furthermore, a normalization was observed in this frequency and in this area, similar to that of the controls.


Assuntos
Fibromialgia , Estimulação Magnética Transcraniana , Encéfalo , Feminino , Fibromialgia/diagnóstico , Fibromialgia/terapia , Humanos , Modalidades de Fisioterapia , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento
8.
Arch Microbiol ; 204(8): 507, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35859215

RESUMO

Vancomycin (VAN) is unable to penetrate the outer membrane of Gram-negative bacteria and reach the target site. One approach to overcome this limitation is to associate it with compounds with permeabilizing or antimicrobial properties. Eudragit E100® (Eu) is a cationic polymer insufficiently characterized for its potential antimicrobial action. Eu-VAN combinations were characterized, the antimicrobial efficacy against Pseudomonas aeruginosa was evaluated and previous studies on the effects of Eu on bacterial envelopes were extended. Time-kill assays showed eradication of P. aeruginosa within 3-6 h exposure to Eu-VAN, whilst VAN was ineffective. Eu showed regrowth in 24 h and delayed colony pigmentation. Although permeabilization of bacterial envelopes or morphological alterations observed by TEM and flow cytometry after exposure to Eu were insufficient to cause bacterial death, they allowed access of VAN to the target site, since Eu-VAN/Van-FL-treated cultures showed fluorescent staining in all bacterial cells, indicating Van-FL internalization. Consequently, Eu potentiated the activity of an otherwise inactive antibiotic against P. aeruginosa. Moreover, Eu-VAN combinations exhibited improved physicochemical properties and could be used in the development of therapeutic alternatives in the treatment of bacterial keratitis.


Assuntos
Pseudomonas aeruginosa , Vancomicina , Antibacterianos/química , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Polímeros/farmacologia , Vancomicina/farmacologia
9.
Enferm. clín. (Ed. impr.) ; 32(4): 234-238, Jul - Ago 2022. tab
Artigo em Espanhol | IBECS | ID: ibc-206154

RESUMO

Introducción: La desnutrición es uno de los factores asociados a la fractura de fémur en pacientes ancianos. Aproximadamente, la mitad de los pacientes ingresados con una fractura de fémur están desnutridos o en situación de riesgo nutricional. Esto puede influir de forma negativa en la evolución de estos pacientes, ya que la desnutrición se asocia a un aumento del riesgo de complicaciones, mayor mortalidad, peor recuperación funcional y estancias hospitalarias más largas. Método: Se ha realizado un estudio observacional retrospectivo con el objetivo de evaluar la prevalencia de desnutrición o riesgo nutricional de los 766 pacientes que ingresaron en el Hospital Universitario Mútua de Terrassa con fractura de fémur entre enero de 2016 y diciembre de 2019. También se han identificado los factores que podrían estar asociados a la desnutrición y se han comparado aspectos como estancia hospitalaria y mortalidad de los pacientes según el grado de desnutrición. Resultados: La edad media de los pacientes es de 84,6 años y el 75% son mujeres. Los resultados del test Mini Nutritional Assessment muestran que el 7,9% de los pacientes están desnutridos y el 31,5% presenta una situación de riesgo nutricional. Conclusiones: Nuestro estudio muestra una elevada prevalencia de desnutrición o de situación de riesgo nutricional en pacientes ingresados con fractura proximal de fémur.(AU)


Introduction: Malnutrition is commonly associated with elderly patients with femoral fractures. Approximately 50% of hospitalized patients with a femoral fracture are malnourished or at risk of malnourishment. This situation may have a negative impact on outcomes and results for these patients. Malnourishment has been associated with an increased risk of complications, mortality, poor recovery, and delayed length of stay. Method: A retrospective observational study was conducted at our institution to evaluate the prevalence of malnutrition or risk of malnourishment in 766 hospitalized patients from January 2016 to December 2019. Furthermore, we identified factors that are associated with malnutrition. We also compared length of stay and mortality according to the degree of malnutrition. Results: The mean age for patients included was 84.6 years and 75% of patients were female. The Mini Nutritional Assessment test results showed 7.9% of patients were malnourished and 31.5% at risk of malnourishment. Conclusions: Our study results indicate a high prevalence of malnutrition and risk of malnourishment in hospitalized elderly patients with a femoral fracture.(AU)


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Desnutrição/complicações , Desnutrição/etiologia , Fraturas do Fêmur/complicações , Fraturas do Fêmur/epidemiologia , Fêmur , Espanha , Estado Nutricional , Osteogênese Imperfeita , Fraturas por Osteoporose , Estudos Retrospectivos , Hospitalização , Mortalidade , 28599 , Qualidade de Vida
10.
Enferm Clin (Engl Ed) ; 32(4): 234-238, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35216950

RESUMO

INTRODUCTION: Malnutrition is commonly associated with elderly patients with femoral fractures. Approximately 50% of hospitalized patients with a femoral fracture are malnourished or at risk of malnourishment. This situation may have a negative impact on outcomes and results for these patients. Malnourishment has been associated with an increased risk of complications, mortality, poor recovery, and delayed length of stay. METHOD: A retrospective observational study was conducted at our institution to evaluate the prevalence of malnutrition or risk of malnourishment in 766 hospitalized patients from January 2016 to December 2019. Furthermore, we identified factors that are associated with malnutrition. We also compared length of stay and mortality according to the degree of malnutrition. RESULTS: The mean age for patients included was 84.6 years and 75% of patients were female. The Mini Nutritional Assessment test results showed 7.9% of patients were malnourished and 31.5% at risk of malnourishment. CONCLUSIONS: Our study results indicate a high prevalence of malnutrition and risk of malnourishment in hospitalized elderly patients with a femoral fracture.


Assuntos
Fraturas do Fêmur , Desnutrição , Idoso , Idoso de 80 Anos ou mais , Feminino , Fraturas do Fêmur/complicações , Fraturas do Fêmur/epidemiologia , Fêmur , Hospitais , Humanos , Masculino , Desnutrição/complicações , Desnutrição/etiologia , Estado Nutricional , Prevalência
11.
Acta Psychol (Amst) ; 221: 103453, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34856529

RESUMO

Interpersonal coordination of body movement-or the similarity in patterning and timing of body movement between interaction partners over time-is a well-documented phenomenon in face-to-face (FTF) conversation. The present study will investigate the degree to which interpersonal coordination is impacted by the amount of visual information available and the type of interaction conversation partners are having. To do so within a naturalistic context, we take advantage of changes induced by the 2020 COVID-19 pandemic. The pandemic has changed communication, with mitigation efforts having forced nearly everyone to engage over videoconferencing (VC) platforms (which limit body visibility but not face visibility) or to meet FTF with public health constraints (which limit face visibility but not body visibility). We will ask 69 pairs of participants to communicate in one of three ways: (1) socially distanced FTF while wearing masks; (2) VC in a laboratory where each partner will see one another's full torso; or (3) VC in a remote setting where each partner will see only one another's face and shoulders. Each pair will hold three conversations: (a) affiliative, (b) argumentative, and (c) task-based. We will quantify interpersonal coordination by extracting overall amounts of movement from videos of the participants using well-validated computer vision methods and then calculating the relationship between the two participants' movement using nonlinear time series analyses. In doing so, we will be able to identify the degree to which visual information and conversational context shape the emergence of interpersonal coordination within now-naturalistic modes of interaction.


Assuntos
COVID-19 , Pandemias , Comunicação , Humanos , Relações Interpessoais , SARS-CoV-2 , Comunicação por Videoconferência
12.
Pediatr. aten. prim ; 23(92): 353-364, oct.- dic. 2021. tab
Artigo em Espanhol | IBECS | ID: ibc-222889

RESUMO

Introducción: las infecciones respiratorias constituyen el principal motivo de consulta y de prescripción de antibióticos en Pediatría. La resistencia antibiótica es un problema de salud pública. Objetivo: conocer los hábitos de prescripción antibiótica en patología respiratoria pediátrica a nivel nacional. Material y métodos: encuesta distribuida por correo electrónico a pediatras españoles y análisis estadístico realizado con el programa SPSS 20.0. Resultados: se obtuvieron 362 encuestas. El 53,1% de los encuestados atiende de 25-35 pacientes al día. La puntuación media de respuestas correctas es de 18,8/23. En otitis media aguda, la indicación de antibioterapia y su duración se realiza según distintos criterios con porcentajes variables, el 98,6% usa amoxicilina, el 97,2% a dosis correctas. En faringoamigdalitis realiza test microbiológico el 79,1%, trata con amoxicilina 50,8% o penicilina 48,6%, durante 10 días el 84%. En patologías respiratorias de etiología vírica (broncoespasmo, catarro y bronquiolitis), más del 90% no indica antibióticos; sin embargo, la presencia de fiebre alta o secreciones verdosas aumenta su prescripción. En neumonía típica, hasta el 59,6% no realiza radiografía, recetan amoxicilina el 94,1%, durante 7 días el 68,3%. En neumonías atípicas el 97,8% prescribe macrólidos. Se observa relación estadísticamente significativa entre: experiencia laboral y puntuación en la encuesta y realización de radiografía; especialidad y calificación del cuestionario, y presión asistencial con realización de test microbiológico en faringoamigdalitis. Conclusiones: observamos errores en el manejo de antibioterapia en Pediatría. Es necesario diseñar estrategias para la educación de la población y los profesionales sanitarios para realizar un uso juicioso de antibióticos (AU)


Introduction: respiratory infections are the most frequent presenting complaint and reason for prescription of antibiotherapy in paediatric care. Antibiotic resistance is a public health problem. Objective: to assess antibiotic prescription practices in the management of paediatric respiratory illness throughout Spain. Material and methods: we conducted a survey of Spanish paediatricians distributing a questionnaire by email. The statistical analysis was performed with the software SPSS version 20.0. Results: we received 362 responses. We found that 53.1% of respondents managed 25-35 patients daily. The mean number of correct answers was 18.8 out of 23. In the case of acute otitis media, respondents determined the indication and duration of antibiotherapy based on different criteria and in variable percentages; 98.6% used amoxicillin, and 97.2% prescribed it at correct doses. In the case of pharyngitis, 79.1% ordered microbiological tests, 50.8% prescribed amoxicillin and 48.6% penicillin, and 84% prescribed treatment for 10 days. When it came to respiratory illnesses of viral aetiology (bronchospasm, common cold and bronchiolitis), more than 90% did not prescribe antibiotics, although the presence of high fever or green nasal discharge was associated with more frequent prescription. In the case of typical pneumonia, up to 59.6% did not order a chest radiograph, 94.1% prescribed amoxicillin, and 68.3% prescribed treatment courses lasting 7 days. For atypical pneumonia, 97.8% prescribed macrolides. We found a statistically significant association between the years of experience and both the score in the questionnaire and the use of chest radiography; between the speciality of the clinician and the questionnaire score, and between physician workload and the ordering of microbiological tests in cases of pharyngitis (AU)


Assuntos
Humanos , Criança , Antibacterianos/administração & dosagem , Prescrições de Medicamentos/estatística & dados numéricos , Infecções Respiratórias/tratamento farmacológico , Padrões de Prática Médica , Inquéritos e Questionários
13.
J Autism Dev Disord ; 50(5): 1479-1496, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-30051188

RESUMO

The social and motor context in which restricted and repetitive behaviors (RRBs) occur in autism and their relationship to social traits are not well-understood. Participants with and without autism completed tasks that varied in social and motor engagement and RRB frequency was measured. Motor and verbal RRBs were most common, RRBs varied based on motor and social context for participants with autism, and social engagement was associated with lower motor and verbal RRBs. Significant correlations between RRBs and autism severity, social synchrony, and nonverbal mental age were also found. This research confirms the importance of context for understanding RRBs during on-going tasks and raises questions about whether the factors that elicit vocal and motor RRBs are unique for individual children.


Assuntos
Transtorno Autístico/psicologia , Atividade Motora , Comportamento Social , Transtorno de Movimento Estereotipado/psicologia , Criança , Feminino , Humanos , Inteligência , Masculino , Meio Social , Análise e Desempenho de Tarefas
14.
Mar Pollut Bull ; 150: 110704, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31740180

RESUMO

Estuaries are very sensitive ecosystems to human activities and the natural evolution of their drainage basins located upstream. Pollution derived from human activities, such as historical mining or recent industrial wastes, can significantly affect their environmental quality. This paper analyzes the silver and copper contents of four cores extracted in two estuaries of SW Spain. Its chronology and vertical evolution allow to differentiate the effects of several pollution episodes (natural, Roman, 19th-20th centuries) on its different sedimentary environments in the last 6 million years. Possible future applications are included in the fields of environmental management or even education.


Assuntos
Cobre/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos , Prata/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Ecossistema , Estuários , Humanos , Espanha
15.
mBio ; 10(4)2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31387900

RESUMO

Staphylococcus aureus is an important human pathogen whose success is largely attributed to its vast arsenal of virulence factors that facilitate its invasion into, and survival within, the human host. The expression of these virulence factors is controlled by the quorum sensing accessory gene regulator (Agr) system. However, a large proportion of clinical S. aureus isolates are consistently found to have a mutationally inactivated Agr system. These mutants have a survival advantage in the host but are considered irreversible mutants. Here we show, for the first time, that a fraction of Agr-negative mutants can revert their Agr activity. By serially passaging Agr-negative strains and screening for phenotypic reversion of hemolysis and subsequent sequencing, we identified two mutational events responsible for reversion: a genetic duplication plus inversion event and a poly(A) tract alteration. Additionally, we demonstrate that one clinical Agr-negative methicillin-resistant S. aureus (MRSA) isolate could reproducibly generate Agr-revertant colonies with a poly(A) tract genetic mechanism. We also show that these revertants activate their Agr system upon phagocytosis. We propose a model in which a minor fraction of Agr-negative S. aureus strains are phase variants that can revert their Agr activity and may act as a cryptic insurance strategy against host-mediated stress.IMPORTANCEStaphylococcus aureus is responsible for a broad range of infections. This pathogen has a vast arsenal of virulence factors at its disposal, but avirulent strains are frequently isolated as the cause of clinical infections. These isolates have a mutated agr locus and have been believed to have no evolutionary future. Here we show that a fraction of Agr-negative strains can repair their mutated agr locus with mechanisms resembling phase variation. The agr revertants sustain an Agr OFF state as long as they exist as a minority but can activate their Agr system upon phagocytosis. These revertant cells might function as a cryptic insurance strategy to survive immune-mediated host stress that arises during infection.


Assuntos
Proteínas de Bactérias/genética , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/metabolismo , Transativadores/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Duplicação Gênica , Regulação Bacteriana da Expressão Gênica , Humanos , Mutação , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Staphylococcus aureus/crescimento & desenvolvimento , Transativadores/metabolismo
17.
PLoS One ; 13(3): e0193906, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29505608

RESUMO

Even high functioning children with Autism Spectrum Disorder (ASD) exhibit impairments that affect their ability to carry out and maintain effective social interactions in multiple contexts. One aspect of subtle nonverbal communication that might play a role in this impairment is the whole-body motor coordination that naturally arises between people during conversation. The current study aimed to measure the time-dependent, coordinated whole-body movements between children with ASD and a clinician during a conversational exchange using tools of nonlinear dynamics. Given the influence that subtle interpersonal coordination has on social interaction feelings, we expected there to be important associations between the dynamic motor movement measures introduced in the current study and the measures used traditionally to categorize ASD impairment (ADOS-2, joint attention and theory of mind). The study found that children with ASD coordinated their bodily movements with a clinician, that these movements were complex and that the complexity of the children's movements matched that of the clinician's movements. Importantly, the degree of this bodily coordination was related to higher social cognitive ability. This suggests children with ASD are embodying some degree of social competence during conversations. This study demonstrates the importance of further investigating the subtle but important bodily movement coordination that occurs during social interaction in children with ASD.


Assuntos
Transtorno do Espectro Autista/psicologia , Criança , Comunicação , Emoções/fisiologia , Feminino , Humanos , Relações Interpessoais , Masculino , Comunicação não Verbal/psicologia , Habilidades Sociais
18.
An. pediatr. (2003. Ed. impr.) ; 87(5): 245-252, nov. 2017. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-168550

RESUMO

Introducción: La nutrición adecuada es uno de los objetivos primordiales en el manejo de los recién nacidos prematuros. Sin embargo, la falta de evidencia en cuanto a cuál es la mejor estrategia para alcanzar este objetivo da lugar a que exista una gran variabilidad en las prácticas de alimentación. Esta variabilidad podría estar relacionada con las diferencias que existen en la incidencia de complicaciones como la enterocolitis necrosante (ECN). Objetivo: Valorar la variabilidad en las prácticas sobre alimentación entre las unidades neonatales de la red SEN-1500. Método: Estudio transversal, mediante cuestionario, solicitando información sobre alimentación del recién nacido de muy bajo peso (RNMBP) (leche donada, momento de inicio, trófica, incrementos, fortificantes, probióticos) en el año 2013. Resultados: Contestaron 60/98 hospitales; la tasa de respuesta fue mayor en centros con más de 50 RNMBP/año (30/31). El 67% tienen protocolo de alimentación, el 52% refieren variabilidad en su unidad y el 25% disponen de leche donada. Se inicia la alimentación en las primeras 48 h, aunque se retrasa en las edades más bajas aun en ausencia de fallo hemodinámico. Además de la inestabilidad hemodinámica hay otras situaciones por las que se demora su inicio (ausencia de leche materna, CIR, flujo umbilical alterado, asfixia), mientras que raramente se retrasa por ausencia de meconio o por mantener un catéter umbilical. Por debajo de 25 semanas la mitad comienzan directamente con incrementos progresivos en lugar de nutrición trófica. Los incrementos raramente alcanzan 30 ml/kg/día. Casi todos usan fortificantes y vitaminas. El uso de probióticos es excepcional. Conclusiones: Existe gran variabilidad en la política de alimentación del RNMBP entre las unidades neonatales españolas. Aunque algunas diferencias en las prácticas de alimentación están justificadas por la falta de evidencia, hay intervenciones que sí han demostrado su eficacia, como disponer de un protocolo de alimentación (basado en pruebas) o tener acceso a leche donada; su implementación en todos los centros podría disminuir la incidencia de ECN y mejorar el estado nutricional de los RNMBP (AU)


Introduction: Proper nutrition is one of the primary objectives in the management of preterm infants. However, lack of evidence on the best strategy to achieve this objective has led to a great variability in feeding practices. This variability may be related to the differences in the incidence of complications, such as necrotising enterocolitis (NEC). Objective: The aim of this study is to assess the variability in clinical practice regarding enteral feeding in SEN-1500 Spanish network. Method: An observational study was conducted using a questionnaire sent out in 2013 requesting information about feeding very low birth weight (VLBW) neonates (bank milk, start time, trophic feeding, increases, fortifiers and probiotics). Results: Responses were received from 60 of the 98 hospitals. The response rate was higher in centres with more than 50VLBW/year (30/31). Just over two-thirds (67%) have feeding protocols, and 52% refer to variability within their unit. A milk bank is available in 25% of the units. First feeding occurs fairly evenly throughout first 48hours, although it is delayed in lower gestational ages, even when there is no haemodynamic failure. In addition to hemodynamic instability there are other situations when the start is delayed (absence of breast milk, CIR, altered umbilical flow, asphyxia), while it is rarely delayed by absence of meconium or maintain an umbilical catheter.Half of those under 25 weeks begin directly with progressive increases instead of trophic feeding. Increases rarely reach 30ml/kg/day. Almost all use fortification and vitamins. There was a significant use of probiotics at the time of the survey. Conclusions: There is great variability in enteral nutrition policies in VLBW in Spain. Although some differences are justified by the lack of evidence, there are other interventions that have proven to be effective, such as evidence-based protocols or access to donor milk. Implementation in all the units could reduce the incidence of NEC and improve the nutritional status (AU)


Assuntos
Humanos , Nutrição do Lactente , Nutrição Enteral/métodos , Doenças do Prematuro/dietoterapia , Recém-Nascido Prematuro/crescimento & desenvolvimento , Enterocolite Necrosante/dietoterapia , Pesquisas sobre Atenção à Saúde/estatística & dados numéricos , Bancos de Leite Humano/estatística & dados numéricos , Recém-Nascido de muito Baixo Peso
19.
Sci Rep ; 7(1): 12880, 2017 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-29038545

RESUMO

In certain conditions, members of the Lactobacillus genus are auxotrophs that have fastidious requirements for growth. Notably, Lactobacillus cannot grow in M9 medium, a minimal synthetic medium used for Escherichia coli. However, we found that some Lactobacillus strains can be grown in M9 when co-cultured with E. coli K-12. In the co-culture, L. casei proliferates exponentially, reaching cell densities of 108 CFU (colony-forming unit) ml-1 in 6 h and dominating E. coli in the late growth phase. Spent medium from E. coli grown overnight lacked this growth-promoting effect on L. casei. Similarly, the effect was not observed when the species were separated by a 0.4-µm membrane. Microscopic observations showed that L. casei are embedded in the micro-scale clusters of E. coli in the early growth phase. This study describes for the first time the ability of a Lactobacillus species to grow in minimal medium when in close proximity with co-cultured bacteria.


Assuntos
Meios de Cultura/farmacologia , Ecossistema , Escherichia coli/citologia , Lacticaseibacillus casei/crescimento & desenvolvimento , Técnicas de Cocultura , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Lacticaseibacillus casei/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
20.
Autism Res ; 10(10): 1687-1699, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28590041

RESUMO

Impairments in social interaction and communicating with others are core features of autism spectrum disorder (ASD), but the specific processes underlying such social competence impairments are not well understood. An important key for increasing our understanding of ASD-specific social deficits may lie with the social motor synchronization that takes place when we implicitly coordinate our bodies with others. Here, we tested whether dynamical measures of synchronization differentiate children with ASD from controls and further explored the relationships between synchronization ability and motor control problems. We found (a) that children with ASD exhibited different and less stable patterns of social synchronization ability than controls; (b) children with ASD performed motor movements that were slower and more variable in both spacing and timing; and (c) some social synchronization that involved motor timing was related to motor ability but less rhythmic synchronization was not. These findings raise the possibility that objective dynamical measures of synchronization ability and motor skill could provide new insights into understanding the social deficits in ASD that could ultimately aid clinical diagnosis and prognosis. Autism Res 2017, 10: 1687-1699. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Transtorno do Espectro Autista/psicologia , Relações Interpessoais , Destreza Motora/fisiologia , Criança , Feminino , Humanos , Masculino
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