High-Pressure Processing Effects on Microbiological Stability, Physicochemical Properties, and Volatile Profile of a Fruit Salad.

Nowadays, consumers are more aware of the effects of their diet on their health, and thus demand natural or minimally processed food products. Therefore, research has focused on processes that assure safe products without jeopardizing their nutritional properties. In this context, this work aimed to evaluate the effects of high-pressure processing (550 MPa/3 min/15 °C, HPP) on a fruit salad (composed of melon juice and pieces of Golden apple and Rocha pear) throughout 35 days of storage at 4 °C. For the physicochemical properties analysed (browning degree, polyphenol oxidase activity, antioxidant activity (ABTS assay), and volatile profile), a freshly made fruit salad was used, while for the microbiological tests (total aerobic mesophiles, and yeast and moulds) spoiled melon juice was added to the fruit salad to increase the microbial load and mimic a challenge test with a high initial microbial load. It was determined that processed samples were more microbiologically stable than raw samples, as HPP enabled a reduction of almost 4-log units of both total aerobic mesophiles and yeasts and moulds, as well as an almost 1.5-fold increase in titratable acidity of the unprocessed samples compared to HPP samples. Regarding browning degree, a significant increase (p < 0.05) was observed in processed versus unprocessed samples (roughly/maximum 68%), while the addition of ascorbic acid decreased the browning of the samples by 29%. For antioxidant activity, there were no significant differences between raw and processed samples during the 35 days of storage. An increase in the activity of polyphenol oxidase immediately after processing (about 150%) was confirmed, which was generally similar or higher during storage compared with the raw samples. Regarding the volatile profile of the product, it was seen that the compounds associated with melon represented the biggest relative percentage and processed samples revealed a decrease in the relative quantity of these compounds compared to unprocessed. Broadly speaking, HPP was shown to be efficient in maintaining the stability and overall quality of the product while assuring microbial safety (by inactivating purposely inoculated microorganisms), which allows for longer shelf life (7 versus 28 days for unprocessed and processed fruit salad, respectively).

Impact of obesity and ovariectomy on respiratory function in female mice.

Obesity and the corresponding variations in female sex hormones are associated with severe lung disease. We determined the potential effects of obesity and sex hormones in female mice by investigating changes in lung structure and respiratory function in an obesity model induced by postnatal overnutrition. Obese female mice exhibited pronounced weight gain, abdominal fat accumulation and collagen type I deposition in the airways. However, neither elastic tissue nor estrogen receptors-α/-ß were affected in obese female mice after ovariectomy or sham-operated mice. Bronchoconstriction in response to methacholine challenge in obese sham-operated mice was higher than in the obese group after ovariectomy. Our results suggest that the coexistence of obesity and ovariectomy impacted on respiratory system and airway resistance (attenuates bronchoconstriction after methacholine), on collagen I deposition and on airway estrogen ß-receptors of mice.

Endothelial Dysfunction Induced by Cadmium and Mercury and its Relationship to Hypertension.

Hypertension is an important public health concern that affects millions globally, leading to a large number of morbidities and fatalities. The etiology of hypertension is complex and multifactorial, and it involves environmental factors, including heavy metals. Cadmium and mercury are toxic elements commonly found in the environment, contributing to hypertension. We aimed to assess the role of cadmium and mercury-induced endothelial dysfunction in the development of hypertension. A narrative review was carried out through database searches. In this review, we discussed the critical roles of cadmium and mercury in the etiology of hypertension and provided new insights into potential mechanisms of their effect, focusing primarily on endothelial dysfunction. Although the mechanisms by which cadmium and mercury induce hypertension have yet to be completely elucidated, evidence for both implicates impaired nitric oxide signaling in their hypertensive etiology.

Assessment of child development in premature babies based on the ICF biopsychosocial model.

BACKGROUND: The International Classification of Functionality (ICF) has been recommended to enable a broader and more holistic view of an individual's health condition. In addition, it works as an important reference for multiprofessional teams. In low-income countries, like Brazil, the attempts to systematize and incorporate the ICF model in health services has been a challenge. AIM: The aim was to analyze the development of premature babies considering the biopsychosocial model of the ICF. DESIGN: A longitudinal study. SETTING: Maternity in the northeast Brazil. POPULATION: Thirty-five premature babies were evaluated in the first stage and 20 in the second. METHODS: Pre, perinatal, socioeconomic data and environmental factors were collected, and general movements assessed during the 38th (±1.79) week of corrected gestational age. The Age and Stages Questionnaire (ASQ-3) was used to assess child development, in the 13th (±1.50) month of life. The instruments were chosen with the objective of evaluating information necessary for the follow-up of premature infants and to represent the five domains of the ICF. RESULTS: Of the 35 newborns initially evaluated, 20 were reassessed at 1 year of age and 70% were boys. In the function and structure domain, 55% exhibited altered general movements and 35% grade 1 intraventricular hemorrhage; in activity and participation, 15% displayed delayed communication, 20% delayed ample motor coordination, 40% fine motor coordination and problem resolution and 35% personal/social delay in the ASQ-3. Only one item of the personal factors (male sex) and function and structure domain (intraventricular hemorrhage) exhibited an association with atypical child development. CONCLUSIONS: Given the susceptibility of premature newborn neurodevelopment and the magnitude of the biopsychosocial model of the ICF, even at this early stage of life, it was possible to observe the influence of personal factors, body function and structure domains on atypical child development. CLINICAL REHABILITATION IMPACT: The care for the premature newborn with global look of the classification of functioning, disability and health.

Activity of carbonyl cyanide-3-chlorophenylhydrazone on biofilm formation and antimicrobial resistance in Pseudomonas aeruginosa using quantum dots-meropenem conjugates as nanotools.

Hospital infections associated with multidrug-resistant (MDR) Pseudomonas aeruginosa are a worldwide public health problem. Efflux systems and biofilm formation are mechanisms related to resistance to carbapenemics. In this study, quantum dots (QDs) were used to evaluate the effect of carbonyl cyanide-3-chlorophenylhydrazone (CCCP), an efflux pump system inhibitor, on biofilm formation and antimicrobial resistance profile of P. aeruginosa strains. For this, QDs were covalently conjugated to meropenem (MPM) and incubated with a P. aeruginosa resistant isolate (P118) or a control sensitive strain (ATCC Pa27853). P118 was also analyzed with conjugates after previous CCCP efflux inhibitor incubation. Fluorescence microscopy images showed that both sensitive and resistant bacteria were efficiently labeled. Nevertheless, P118 isolates presented fluorescent cell agglomerates, suggesting biofilm formation. The addition of the CCCP changed the labeling profile of the resistant isolate, and the absence of agglomerates was observed, indicating no biofilm formation. Genetic assays revealed the presence of MexA and MexE genes encoding channel proteins from efflux pump systems in both resistant and sensitive strains. Disk-diffusion and broth microdilution tests determined drug susceptibility profiles in the presence and absence of CCCP for P118 isolates. We verified that the CCCP efflux system inhibitor may contribute to P. aeruginosa resistant phenotype reduction for some antimicrobials. This study verified the efficiency of QD-MPM conjugates to trigger and study biofilm formation, or its inhibition, before and after CCCP addition. QDs conjugated to antimicrobials can be used as nanotools to investigate multidrug-resistant bacterial strains on biofilm formation.

Detection of Stressful Situations Using GSR While Driving a BCI-controlled Wheelchair.

This paper analyzes the galvanic skin response (GSR) recorded from healthy and motor disabled people while steering a robotic wheelchair (RobChair ISR-UC prototype), to infer whether GSR can help in the recognition of stressful situations. Seven healthy individuals and six individuals with motor disabilities were asked to drive the RobChair by means of a brain-computer interface in indoor office environments, including complex scenarios such as passing narrow doors, avoiding obstacles, and with situations of unexpected trajectories of the wheelchair (controlled by an operator without users knowledge). All these driving situations can trigger emotional arousals such as anxiety and stress. A method called feature-based peak detection (FBPD) was proposed for automatic detection of skin conductance response (SCR) which proved to be very effective compared to the state-of-the-art methods. We found that SCR was elicited in 100% of the occurrences of collisions (lateral scrapings) and 94% of unexpected trajectories.

Prognostic factors in MNU and DMBA-induced mammary tumors in female rats.

Chemically-induced mammary tumors in rats by the carcinogens 1-methyl-1-nitrosourea- (MNU) and 7,12-dimethylbenz[a]anthracene (DMBA) are the most widely used models for studies related with human breast cancer. This study aimed to evaluate the immunoexpression of the prognostic factors estrogen receptor α (ERα), progesterone receptor (PR) and Ki-67, in MNU and DMBA-induced rat mammary tumors, in order to know the model that best suits to woman breast cancer. Twenty-eight MNU-induced and 16 DMBA-induced mammary tumors in virgin female Sprague-Dawley rats were analyzed. The expression of the prognostic markers ERα, PR and Ki-67 proliferation index (Ki-67 PI) was assessed by immunohistochemistry. Mitotic activity index (MAI) was also evaluated. More than one histological pattern was identified in each mammary tumor. Carcinomas constituted the lesions most frequently induced by both carcinogens: 33 MNU-induced carcinomas and 23 DMBA-induced carcinomas. All MNU and DMBA-induced mammary carcinomas were ER+/PR+, with a higher expression of ERα when compared with PR. Tumors' weight, the expression of ERα, PR, Ki-67 PI and MAI were higher in MNU-induced mammary carcinomas when compared with the DMBA-induced ones. Statistically significant differences between groups were observed for ERα, PR and MAI (p<0.05). The higher KI-67 PI and MAI in MNU-induced mammary carcinomas are suggestive of a higher aggressiveness of these carcinomas when compared with the DMBA-induced ones, and consequently a worse response to the therapy and a worse prognosis. In this way, the use of the rat model of MNU-induced mammary tumors is advised in experimental protocols aiming to study more aggressive mammary tumors within the group of double-positive mammary tumors (ER+/PR+).

Improving discrimination in the grading of rat mammary tumors using two-dimensional mapping of histopathological observations.

This work aims at characterizing rat mammary tumors induced by 7,12-dimethylbenz(a)anthracene (DMBA) and the respective malignancy potential, commonly graded with histopathology features grouped by intensity levels. Tumors were described over fourteen multiple ranged microscopic parameters and a comprehensive characterization of the histological patterns and their relation with tumor grade was carried out by principal component analysis (PCA). The number of histological patterns present on a tumor tends to correlate with malignant features. High grade tumors are characterized by the presence of several structural patterns, with cribriform prevalence and necrosis. The cribriform pattern correlates with grading, i.e., tumors having a higher predominance of the cribriform pattern are likely to be more malignant. The findings may represent a benchmark for similar characterization studies in other models.

Assisted navigation based on shared-control, using discrete and sparse human-machine interfaces.

This paper presents a shared-control approach for Assistive Mobile Robots (AMR), which depends on the user's ability to navigate a semi-autonomous powered wheelchair, using a sparse and discrete human-machine interface (HMI). This system is primarily intended to help users with severe motor disabilities that prevent them to use standard human-machine interfaces. Scanning interfaces and Brain Computer Interfaces (BCI), characterized to provide a small set of commands issued sparsely, are possible HMIs. This shared-control approach is intended to be applied in an Assisted Navigation Training Framework (ANTF) that is used to train users' ability in steering a powered wheelchair in an appropriate manner, given the restrictions imposed by their limited motor capabilities. A shared-controller based on user characterization, is proposed. This controller is able to share the information provided by the local motion planning level with the commands issued sparsely by the user. Simulation results of the proposed shared-control method, are presented.

An assisted navigation training framework based on judgment theory using sparse and discrete human-machine interfaces.

This paper aims to present a new framework to train people with severe motor disabilities steering an assisted mobile robot (AMR), such as a powered wheelchair. Users with high level of motor disabilities are not able to use standard HMIs, which provide a continuous command signal (e. g. standard joystick). For this reason HMIs providing a small set of simple commands, which are sparse and discrete in time must be used (e. g. scanning interface, or brain computer interface), making very difficult to steer the AMR. In this sense, the assisted navigation training framework (ANTF) is designed to train users driving the AMR, in indoor structured environments, using this type of HMIs. Additionally it provides user characterization on steering the robot, which will later be used to adapt the AMR navigation system to human competence steering the AMR. A rule-based lens (RBL) model is used to characterize users on driving the AMR. Individual judgment performance choosing the best manoeuvres is modeled using a genetic-based policy capturing (GBPC) technique characterized to infer non-compensatory judgment strategies from human decision data. Three user models, at three different learning stages, using the RBL paradigm, are presented.

Aspectos moleculares da transmissäo sináptica / Molecular aspects of synaptic transmission

O Sistema Nervoso Central produz o nosso estado consciente mediante um contínuo fluxo de informaçöes e armazenamento de memórias ao longo da vida, a partir de diferentes estímulos externos. Ao mesmo tempo, controla a concentraçäo dos nossos fluidos internos e o trabalho de músculos e glândulas. A transmissäo sináptica é o processo básico de toda esta atividade. Bilhöes de neurônios se comunicam entre si via milhares de sinapses, e cada sinapse, por sua vez, é uma estrutura regulada independentemente. A partir desta complexidade, em lugar de caos, surge uma singular ordem na informaçäo processada pelo cérebro. A secreçäo de neurotransmissores na zona ativa da sinapse é o evento primário da comunicaçäo interneuronal. Este processo é regulado por um tráfego de membranas altamente orquestrado dentro do terminal pré-sináptico. Os neurotransmissores säo armazenados em vesículas sinápticas. A despolarizaçäo de um terminal nervoso por um potencial de açäo resulta na abertura de canais de cálcio, operados por voltagem. O influxo do Ca²+ resultante deflagra a exocitose, que é uma rápida fusäo de vesículas com a membrana plasmática, liberando neurotransmissores para a fenda sináptica. A exocitose envolve a junçäo de proteínas intrínsecas das membranas plasmáticas, vesicular e pré-sináptica, mediante proteínas específicas de ancoragem e fusäo na zona ativa (SNARE). Em seguida à liberaçäo, as membranas das vesículas säo rapidamente reincorporadas via endocitose e recicladas dentro do terminal sináptico. O terminal é, portanto, uma unidade autônoma que contém todos os elementos requeridos para a exocitose das vesículas, as proteínas responsáveis pela biossíntese do neurotransmissor e recaptaçäo das vesículas. Uma vez liberado, o neurotransmissor difunde através da fenda sináptica e interage com proteínas receptoras na membrana do neurônio pós-sináptico produzindo, em uma fraçäo de milissegundo, uma permeabilidade intensa e temporária aos íons Na+ e K+, provocando a despolarizaçäo total de cerca de 100 mV desde um potencial de repouso em torno de -60mV. Isto gera um potencial de açäo que se difunde ao longo da membrana do neurônio pós-sináptico, podendo alcançar o seu próprio terminal e deflagrar novo movimento de Ca²+ para o citosol, gerando um novo potencial. Várias proteínas dentro do terminal pós-sináptico estäo envolvidas neste processo.

Desenvolvimento de bebida láctea a base de flocos de abóbora / Development of a milk beverage based on pumpkin flakes

Um dos graves problemas de saúde pública no Nordeste brasileiro é a hipovitaminose A que se encontra associada, dentre outros factores, ao desmame precoce. Com vistas a minimizar o problema foi desenvolvida uma bebida láctea para desmame tendo como base a abóbora, vegetal que constitui uma importante fonte de carotenóides, cujo consumo é largamente difundido na Regiao. A metodologia envolveu a secagem da abóbora em "Drum dryer" (pressao máxima de vapor 6 atm, superfície do cilindro 0,75 m2 e velocidade 1 rpm) para a obtençao dos flocos, que foram analisados quanto a sua composiçao centesimal, carotenóides totais beta-caroteno, bolores e leveduras e coliformes totais a fecais, seguida do desenvolvimento de formulaçoes com açúcar e leite em pó integral, tendo em vista as recomendaçoes nutricionais (FAO/OMS) para a faixa etária de 6 a 12 meses. A aceitabilidade das formulaçoes foi testada através de um painel composto por 6 juízes treinados. Segundo os resultados, os flocos apresentaram rendimento 7 por cento, umidade 4,84 por cento; proteínas 4,0 por cento; cinzas 5,50 por cento; lipídeos 1,30 por cento; fibra 6,22 por cento; carboidratos 78,14 por cento; carotenóides totais 115,08 mug/g; beta-caroteno 80,64 mug/g; ausência de coliformes e 4,0 x 10(2) UFC/g de bolores e leveduras. A formulaçao selecionada após reconstituiçao com água (q.s.p. para 100 ml) atende 45 por cento das necessidades calóricas diárias das crianças e 100 por cento de vitamina A e proteínas, considerando uma ingestao de 400 ml/dia.