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1.
Global Health ; 19(1): 8, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36726118

RESUMO

BACKGROUND: Parents are exposed to breastmilk substitutes and baby foods marketing on the internet and social media, which hinders adequate breastfeeding and complementary feeding. This study identifies digital marketing strategies for breastmilk substitutes, specifically commercial milk formula and baby foods used by the industry to influence infant and young children's feeding practices in Mexico and proposes regulatory recommendations that can be useful for similar countries. METHODS: Qualitative study based on the CLICK monitoring framework developed by the World Health Organization, adapted for digital marketing of commercial milk formula and baby foods. Semi-structured interviews (n = 53) with key actors were conducted between November 2020 and March 2021, and used grounded theory for the analysis and interpretation with the MAXQDA 20 software. RESULTS: Commercial milk formula and baby food companies use digital media to contact and persuade parents to use their products by sending electronic newsletters with advertising. Companies hire influencers to market their products because there is no regulation prohibiting the advertisement of breastmilk substitutes on social media, and promote formula among health professionals inviting them to participate in sponsored webinars on infant nutrition, ignoring conflict of interest and the International Code of Marketing of Breastmilk Substitutes. Parents trust formula and baby food advertisements, which use emotional messages and health and nutrition claims to encourage their consumption. Health professionals consider that claims contribute to the indiscriminate use of formula, and some actors propose the use of plain packaging for these products. CONCLUSIONS: Breastmilk substitutes companies promote their products in digital media using unethical strategies that fail to comply with the International Code of Marketing of Breastmilk Substitutes. They generate strong conflicts of interest with health professionals, taking advantage of legal framework gaps and the lack of monitoring and effective sanctions for non-compliers. Updating the legal framework and monitoring compliance, including digital media, is urgently needed to protect children's right to breastfeeding, healthy nutrition and life, and the rights of women to health and informed decision-making.


Assuntos
Internet , Leite Humano , Lactente , Criança , Feminino , Humanos , Pré-Escolar , México , Alimentos Infantis , Marketing , Aleitamento Materno
2.
Sensors (Basel) ; 23(11)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37299881

RESUMO

The use of IoT technology is rapidly increasing in healthcare development and smart healthcare system for fitness programs, monitoring, data analysis, etc. To improve the efficiency of monitoring, various studies have been conducted in this field to achieve improved precision. The architecture proposed herein is based on IoT integrated with a cloud system in which power absorption and accuracy are major concerns. We discuss and analyze development in this domain to improve the performance of IoT systems related to health care. Standards of communication for IoT data transmission and reception can help to understand the exact power absorption in different devices to achieve improved performance for healthcare development. We also systematically analyze the use of IoT in healthcare systems using cloud features, as well as the performance and limitations of IoT in this field. Furthermore, we discuss the design of an IoT system for efficient monitoring of various healthcare issues in elderly people and limitations of an existing system in terms of resources, power absorption and security when implemented in different devices as per requirements. Blood pressure and heartbeat monitoring in pregnant women are examples of high-intensity applications of NB-IoT (narrowband IoT), technology that supports widespread communication with a very low data cost and minimum processing complexity and battery lifespan. This article also focuses on analysis of the performance of narrowband IoT in terms of delay and throughput using single- and multinode approaches. We performed analysis using the message queuing telemetry transport protocol (MQTTP), which was found to be efficient compared to the limited application protocol (LAP) in sending information from sensors.


Assuntos
Comunicação , Análise de Dados , Idoso , Feminino , Humanos , Gravidez , Pressão Sanguínea , Fontes de Energia Elétrica , Exercício Físico , Internet das Coisas , Computação em Nuvem
3.
Educ Inf Technol (Dordr) ; : 1-36, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37361787

RESUMO

Messaging platforms are applications, generally mediated by an app, desktop program or the web, mainly used for synchronous communication among users. As such, they have been widely adopted officially by higher education establishments, after little or no study of their impact and perception by the teachers. We think that the introduction of these new tools and the opportunities and challenges they have needs to be studied carefully in order to adopt the model, as well as the tool, that is the most adequate for all parties involved. We already studied the perception of these tools by students, in this paper we examine the teachers' experiences and perceptions through a survey that we validated with peers, and what they think these tools should make or serve so that it enhances students learning and helps them achieve their learning objectives. The survey has been distributed among tertiary education teachers, both in universitary and other kind of tertiary establishments, based in Spain (mainly) and Spanish-speaking countries. We have focused on collecting teachers' preferences and opinions on the introduction of messaging platforms in their day-to-day work, as well as other services attached to them, such as chatbots. What we intend with this survey is to understand their needs and to gather information about the various educational use cases where these tools could be valuable. In addition, an analysis of how and when teachers' opinions towards the use of these tools varies across gender, experience, and their discipline of specialization is presented. The key findings of this study highlight the factors that can contribute to the advancement of the adoption of messaging platforms and chatbots in higher education institutions to achieve the desired learning outcomes.

4.
Eur J Nutr ; 59(3): 1191-1204, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31069458

RESUMO

PURPOSE: Mild/moderate maternal calorie restriction during lactation in rats has been associated with a lower predisposition to obesity and a healthier metabolic profile in adult offspring. Here, we aimed to assess the impact of maternal calorie restriction during lactation on milk composition to identify potential candidate components that could be involved in the programming effects in offspring. METHODS: An untargeted metabolomic approach in milk samples from 20%-calorie-restricted lactating (CRL) dams and their controls was performed. Levels of leptin, adiponectin, and irisin hormones in milk were also determined at lactating days 5, 10, and 15. RESULTS: Metabolomic analyses revealed a different metabolite pattern in milk between controls and CRL dams. 29 differential metabolites were tentatively identified (p < 0.05, FC > 1.5). Among them, myo-inositol, which showed greater levels in milk from CRL rats than controls, may be highlighted as one of the biologically plausible candidates that could be related to the beneficial effects of CRL in offspring. Results regarding myo-inositol were validated spectrophotometrically at days 10 and 15 of lactation, and levels in milk were correlated with maternal plasma levels. In addition, milk from CRL dams presented increased levels of adiponectin, decreased levels of irisin, and no changes in leptin levels vs controls throughout lactation. CONCLUSION: These data reveal important changes in milk composition due to calorie restriction during lactation that may be involved in the metabolic programming of the healthier phenotype of adult offspring. However, the possible contribution of the specific components is yet to be determined.


Assuntos
Restrição Calórica/estatística & dados numéricos , Lactação/metabolismo , Fenômenos Fisiológicos da Nutrição Materna , Metabolômica/métodos , Leite/metabolismo , Animais , Feminino , Modelos Animais , Fenótipo , Ratos , Ratos Wistar
5.
Anal Chem ; 91(3): 2100-2111, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30580508

RESUMO

Surface-enhanced Raman spectroscopy (SERS) has recently emerged as an innovative tool for therapeutic-drug monitoring (TDM), making it an ideal candidate for personalized treatment. Herein, we report a layer-by-layer (LbL) approach for the fabrication of a highly reproducible hybrid SERS substrate based on graphene oxide (GO)-supported l-cysteine-functionalized starlike gold nanoparticles (SAuNPs). These designed substrates were utilized for TDM of paclitaxel and cyclophosphamide in blood serum. The SAuNPs' efficient binding at the edges of GO creates a better SERS hotspot with enhanced Raman sensitivity because of the spacing of ∼2.28 nm between the SAuNPs. In addition, the hierarchically modified substrate with a self-assembled monolayer of zwitterionic amino acid l-cysteines acts like a brush layer to prevent SERS-hotspot blockages and fouling by blood-serum proteins. The antifouling nature of the substrate was determined quantitatively by a bichinchonic acid assay using bovine-serum albumin (BSA) as a protein model on the l-cysteine SAuNPs@GO hybrid substrate (the test) and a cysteamine SAuNPs@GO substrate (the control). The l-cysteine SAuNPs@GO hybrid exhibited 80.57% lower BSA fouling compared with that of the cysteamine SAuNPs@GO substrate. The SERS spectra were acquired within 20 s, with detection limits of 1.5 × 10-8 M for paclitaxel and 5 × 10-9 M for cyclophosphamide in blood serum. Such sensitivities are 4 times and 1 order of magnitude higher than the currently available sophisticated analytical techniques, which involve high costs with each analysis.


Assuntos
Técnicas Biossensoriais , Ciclofosfamida/sangue , Monitoramento de Medicamentos , Paclitaxel/sangue , Soroalbumina Bovina/análise , Animais , Bovinos , Ouro/química , Grafite/química , Humanos , Nanopartículas Metálicas/química , Quinolinas/química , Análise Espectral Raman
6.
Phys Rev Lett ; 120(24): 245501, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29956947

RESUMO

The total energy of acoustic emission (AE) events in externally stressed materials diverges when approaching macroscopic failure. Numerical and conceptual models explain this accelerated seismic release (ASR) as the approach to a critical point that coincides with ultimate failure. Here, we report ASR during soft uniaxial compression of three silica-based (SiO_{2}) nanoporous materials. Instead of a singular critical point, the distribution of AE energies is stationary, and variations in the activity rate are sufficient to explain the presence of multiple periods of ASR leading to distinct brittle failure events. We propose that critical failure is suppressed in the AE statistics by mechanisms of transient hardening. Some of the critical exponents estimated from the experiments are compatible with mean field models, while others are still open to interpretation in terms of the solution of frictional and fracture avalanche models.

7.
Int J Food Sci Nutr ; 67(4): 470-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27018166

RESUMO

Dietary habits strongly influence gut microbiota. The aim of this study was to compare and correlated the abundance of Firmicutes and Bacteroidetes phyla, some representative bacteria of these phyla such as Bacteroides thetaiotaomicron, Prevotella, Faecalibacterium prausnitzii, Clostridium leptum and Bifidobacterium longum as a member of Actinobacteria phylum in young adults with their food intake. Faecal samples used came from lean subjects (BMI = 19.83 ± 0.94 kg/m(2)), overweight (BMI = 27.17 ± 0.51 kg/m(2)) and obese (BMI = 41.33 ± 5.25 kg/m(2)). There were significant differences in total studied gut microbiota between the overweight and lean groups. Members of the Firmicutes phylum, and Bifidobacterium longum, were more abundant in the lean group. The results suggest that diet rich in unsaturated fatty acids and fibre promote an abundant population of beneficial bacteria such as B. longum and Bacteroidetes. However, it has been considered that the results may be biased due to the size of the individuals studied; therefore the results could be only valid for the studied population.


Assuntos
Bacteroidetes/crescimento & desenvolvimento , Dieta/efeitos adversos , Disbiose/etiologia , Firmicutes/crescimento & desenvolvimento , Microbioma Gastrointestinal , Obesidade/microbiologia , Sobrepeso/microbiologia , Adiposidade/etnologia , Adolescente , Adulto , Doenças Assintomáticas , Bacteroidetes/classificação , Bacteroidetes/isolamento & purificação , Índice de Massa Corporal , Dieta/etnologia , Dieta Saudável/etnologia , Gorduras Insaturadas na Dieta/uso terapêutico , Fibras na Dieta/uso terapêutico , Disbiose/complicações , Disbiose/etnologia , Disbiose/prevenção & controle , Fezes/microbiologia , Feminino , Firmicutes/classificação , Firmicutes/isolamento & purificação , Humanos , Masculino , México , Tipagem Molecular , Obesidade/complicações , Obesidade/etnologia , Obesidade/prevenção & controle , Sobrepeso/complicações , Sobrepeso/etnologia , Sobrepeso/prevenção & controle , Adulto Jovem
9.
Rev Biol Trop ; 63(3): 695-704, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26666126

RESUMO

The adults and larvae of Passalidae are subsocial insects commonly found in tropical forests, living in decaying wood gallery systems constructed by adults. Currently, few repots on the larvae of Neotropical Passalidae have been published and information is scarce. In this study, the Passalus (Pertinax) gravelyi Moreira, 1922 larvae is described for the first time, based on ten larval specimens 1 (1° instar), 4 (2° instar), and 5 (3° instar) associated with three adults collected from a single colony at the Parque Nacional do Itatiaia (Itatiaia, Rio de Janeiro, Brazil). The description was carried out based on electronic and digital photographs of diagnostic structures, with some details on the systematic of the species. The larvae of Passalus gravelyi has the general setal 'Pertinax' pattern and differed from others by 16 to 18 setae on the anal ring, the other larvae data from Brazilian species show the anal ring with 10 to 12 setae. A discussion on the presence of sexual dimorphism in 62 species of two and three instars of Passalidae larvae is provided for the first time. Besides, a description of the terminal ampulla present as a cuticular structure found in the medial-ventral area of the 9th abdominal sternite in males is also given. The terminal ampulla was only observed in the Passalidae male larvae and was not visible in female larvae. The terminal ampulla are acknowledged now in males of 64 passalid species, that are taxonomically distributed in world tropical forests, at the Oriental and Australian subfamily Aulacocyclinae (Aulacocyclini & Ceracupini) and the cosmotropical subfamily Passalinae (Solenocyclini, Macrolinini, Passalini, & Proculini).


Assuntos
Besouros/anatomia & histologia , Besouros/classificação , Larva/anatomia & histologia , Larva/classificação , Caracteres Sexuais , Estruturas Animais/anatomia & histologia , Animais , Brasil , Feminino , Masculino
10.
ISA Trans ; 147: 109-117, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38485636

RESUMO

This article presents an observer-based adaptive sliding mode controller for a fully-actuated hexacopter unmanned aerial vehicle, designed for trajectory tracking in a perturbed environment while carrying a cable-suspended payload. Based on the unavailability of a payload swing sensor, an extended high-gain observer is designed to provide full-state and disturbance estimation including payload motion. Such disturbances are compensated into the control loop to dampen the oscillations, thus improving the flight performance of the hexacopter driven by the adaptive control, providing robustness against bounded perturbations and chattering reduction. The stability analysis of the observer-based controller is guaranteed through Lyapunov theory. Simulations using a multibody emulator demonstrate time reduction in payload dampening while controlling the aircraft trajectory, compared to a feedback regulation-based adaptive controller.

11.
Nutrients ; 16(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38613013

RESUMO

This study aims to investigate the potential mechanisms underlying the protective effects of myo-inositol (MI) supplementation during suckling against the detrimental effects of fetal energy restriction described in animal studies, particularly focusing on the potential connections with BDNF signaling. Oral physiological doses of MI or the vehicle were given daily to the offspring of control (CON) and 25%-calorie-restricted (CR) pregnant rats during suckling. The animals were weaned and then fed a standard diet until 5 months of age, when the diet was switched to a Western diet until 7 months of age. At 25 days and 7 months of age, the plasma BDNF levels and mRNA expression were analyzed in the hypothalamus and three adipose tissue depots. MI supplementation, especially in the context of gestational calorie restriction, promoted BDNF secretion and signaling at a juvenile age and in adulthood, which was more evident in the male offspring of the CR dams than in females. Moreover, the CR animals supplemented with MI exhibited a stimulated anorexigenic signaling pathway in the hypothalamus, along with improved peripheral glucose management and enhanced browning capacity. These findings suggest a novel connection between MI supplementation during suckling, BDNF signaling, and metabolic programming, providing insights into the mechanisms underlying the beneficial effects of MI during lactation.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Restrição Calórica , Masculino , Feminino , Gravidez , Animais , Ratos , Tecido Adiposo , Dieta Ocidental , Suplementos Nutricionais
12.
Sci Rep ; 14(1): 11366, 2024 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762543

RESUMO

Placental leptin may impact foetal development. Maternal overnutrition has been linked to increased plasma leptin levels and adverse effects on offspring, whereas choline, an essential nutrient for foetal development, has shown promise in mitigating some negative impacts of maternal obesity. Here, we investigate whether a maternal obesogenic diet alters foetal growth and leptin levels in the foetal stomach, amniotic fluid (AF), and placenta in late gestation and explore the potential modulating effects of maternal choline supplementation. Female rats were fed a control (CD) or a western diet (WD) four weeks before mating and during gestation, half of them supplemented with choline (pregnancy days 11-17). Leptin levels (in foetal stomach, AF, and placenta) and leptin gene expression (in placenta) were assessed on gestation days 20 and 21. At day 20, maternal WD feeding resulted in greater leptin levels in foetal stomach, placenta, and AF. The increased AF leptin levels were associated with a premature increase in foetal weight in both sexes. Maternal choline supplementation partially prevented these alterations, but effects differed in CD dams, causing increased AF leptin levels and greater weight in male foetuses at day 20. Maternal choline supplementation effectively mitigates premature foetal overgrowth induced by an obesogenic diet, potentially linked to increased AF leptin levels. Further research is needed to explore the sex-specific effects.


Assuntos
Líquido Amniótico , Colina , Suplementos Nutricionais , Leptina , Animais , Feminino , Leptina/sangue , Leptina/metabolismo , Gravidez , Colina/administração & dosagem , Líquido Amniótico/metabolismo , Ratos , Masculino , Placenta/metabolismo , Placenta/efeitos dos fármacos , Desenvolvimento Fetal/efeitos dos fármacos , Obesidade/metabolismo , Obesidade/etiologia , Peso Fetal/efeitos dos fármacos , Ratos Sprague-Dawley , Dieta Ocidental/efeitos adversos
13.
Zootaxa ; 3701: 192-206, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26191578

RESUMO

Based on field collections, museum specimens and literature review, we present a checklist of Argentine Passalidae, with a key to their identification. A total of five genera and 24 species are listed, including Passalus quadricollis, Passalus perplexus and Passalus elfriedae as first records for the country.


Assuntos
Besouros/anatomia & histologia , Besouros/classificação , Distribuição Animal , Animais , Argentina , Besouros/fisiologia
14.
IEEE Trans Vis Comput Graph ; 29(7): 3392-3404, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35298381

RESUMO

Unmanned Aerial Vehicles (UAVs) exhibit great agility but usually require an experienced pilot to operate them in certain applications such as inspection for disaster scenarios or buildings. The reduction of cognitive overload when driving this kind of aerial robot becomes a challenge and several solutions can be found in the literature. A new virtual control scheme for reducing this cognitive overload when controlling an aerial robot is proposed in this paper. The architecture is based on a novel interaction Drone Exocentric Advanced Metaphor (DrEAM) located in a Cave Automated Virtual Environment (CAVE) and a real robot containing an embedded controller based on quaternion formulation. The testing room, where real robots are evolving, is located away from the CAVE and they are connected via UDP in a ground station. The user controls manually a virtual drone through the DrEAM interaction metaphor, and the real robot imitates autonomously in real time the trajectory imposed by the user in the virtual environment. Experimental results illustrate the easy implementation and feasibility of the proposed scheme in two different scenarios. Results from these tests show that the mental effort when controlling a drone using the proposed virtual control scheme is lower than when controlling it in direct view. Moreover, the easy maneuverability and controllability of the real drone is also demonstrated in real time experiments.

15.
PLoS One ; 18(12): e0296113, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38096206

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0290581.].

16.
PLoS One ; 18(11): e0290581, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37972064

RESUMO

The Covid-19 pandemic has led to an increase in the awareness of and demand for telemedicine services, resulting in a need for automating the process and relying on machine learning (ML) to reduce the operational load. This research proposes a specialty detection classifier based on a machine learning model to automate the process of detecting the correct specialty for each question and routing it to the correct doctor. The study focuses on handling multiclass and highly imbalanced datasets for Arabic medical questions, comparing some oversampling techniques, developing a Deep Neural Network (DNN) model for specialty detection, and exploring the hidden business areas that rely on specialty detection such as customizing and personalizing the consultation flow for different specialties. The proposed module is deployed in both synchronous and asynchronous medical consultations to provide more real-time classification, minimize the doctor effort in addressing the correct specialty, and give the system more flexibility in customizing the medical consultation flow. The evaluation and assessment are based on accuracy, precision, recall, and F1-score. The experimental results suggest that combining multiple techniques, such as SMOTE and reweighing with keyword identification, is necessary to achieve improved performance in detecting rare classes in imbalanced multiclass datasets. By using these techniques, specialty detection models can more accurately detect rare classes in real-world scenarios where imbalanced data is common.


Assuntos
Pandemias , Telemedicina , Humanos , Redes Neurais de Computação
17.
Nutrients ; 15(3)2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36771278

RESUMO

We aimed to analyze the long-term metabolic effects of leptin supplementation at physiological doses during suckling in the offspring of diet-induced obese rats, together with the potential benefits of improving maternal diet during lactation. Thus, the offspring of: dams fed standard-diet (SD) (CON-dams), dams fed western-diet (WD) before and during gestation and lactation (WD-dams), and dams fed as WD-dams but moved to SD during lactation (REV-dams) were supplemented throughout suckling with leptin or vehicle, and fed SD or WD from weaning to four months. Under SD, leptin treatment significantly improved metabolic profile and body fat accumulation, with stronger effects in the male offspring of CON-dams and REV-dams. Under WD, the offspring of WD-dams presented metabolic alterations that were not evident in the offspring of REV-dams. Moreover, leptin supplementation improved glucose homeostasis in the male offspring of REV-dams. Conversely, leptin supplementation in females born to WD-dams and fed WD from weaning resulted in impaired insulin sensitivity and increased hepatic lipid content. These results highlight the importance of a balanced maternal diet during the perinatal period, especially lactation, for the subsequent metabolic health of the offspring and for the beneficial effects of leptin supplementation during suckling, more evident in the male offspring.


Assuntos
Leptina , Efeitos Tardios da Exposição Pré-Natal , Animais , Feminino , Masculino , Gravidez , Ratos , Adiposidade , Dieta , Lactação , Leptina/metabolismo , Fenômenos Fisiológicos da Nutrição Materna , Obesidade/metabolismo , Parto
18.
Biofactors ; 49(5): 1022-1037, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37227188

RESUMO

We aimed to evaluate whether improving maternal diet during lactation in diet-induced obese rats reverts the impact of western diet (WD) consumption on the metabolome of milk and offspring plasma, as well as to identify potential biomarkers of these conditions. Three groups of dams were followed: control-dams (CON-dams), fed with standard diet (SD); WD-dams, fed with WD prior and during gestation and lactation; and reversion-dams (REV-dams), fed as WD-dams but moved to SD during lactation. Metabolomic analysis was performed in milk at lactation days 5, 10, and 15, and in plasma from their male and female offspring at postnatal day 15. Milk of WD-dams presented, throughout lactation and compared to CON-dams, altered profiles of amino acids and of the carnitine pool, accompanied by changes in other polar metabolites, being stachydrine, N-acetylornithine, and trimethylamine N-oxide the most relevant and discriminatory metabolites between groups. The plasma metabolome profile was also altered in the offspring of WD-dams in a sex-dependent manner, and stachydrine, ergothioneine and the acylcarnitine C12:1 appeared as the top three most discriminating metabolites in both sexes. Metabolomic changes were largely normalized to control levels both in the milk of REV-dams and in the plasma of their offspring. We have identified a set of polar metabolites in maternal milk and in the plasma of the offspring whose alterations may indicate maternal intake of an unbalanced diet during gestation and lactation. Levels of these metabolites may also reflect the beneficial effects of implementing a healthier diet during lactation.


Assuntos
Lactação , Leite , Ratos , Masculino , Feminino , Animais , Leite/química , Leite/metabolismo , Dieta , Biomarcadores/metabolismo
19.
Microorganisms ; 11(7)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37512821

RESUMO

Bifidobacterium longum is considered a microorganism with probiotic potential, which has been extensively studied, but these probiotic effects are strain dependent. This work aims to characterize the probiotic potential, based on the biochemical and genomic functionality, of B. longum LBUX23, isolated from neonates' feces. B. longum LBUX23 contains one circular genome of 2,287,838 bp with a G+C content of 60.05%, no plasmids, no CRISPR-Cas operon, possesses 56 tRNAs, 9 rRNAs, 1 tmRNA and 1776 coding sequences (CDSs). It has chromosomally encoded resistance genes to ampicillin and dicloxacillin, non-hemolytic activity, and moderate inhibition of Escherichia coli ATCC 25922 and to some emergent pathogen's clinical strains. B. longum LBUX23 was able to utilize lactose, sucrose, fructooligosaccharides (FOS), and lactulose. The maximum peak of bacterial growth was observed in sucrose and FOS at 6 h; in lactose and lactulose, it was shown at 8 h. B. longum LBUX23 can survive in gastrointestinal conditions (pH 4 to 7). A decrease in survival (96.5 and 93.8%) was observed at pH 3 and 3.5 during 120 min. argC, argH, and dapA genes could be involved in this tolerance. B. longum LBUX23 can also survive under primary and secondary glyco- or tauro-conjugated bile salts, and a mixture of bile salts due to the high extracellular bile salt hydrolase (BSH) activity (67.3 %), in taurocholic acid followed by taurodeoxycholic acid (48.5%), glycocholic acid (47.1%), oxgall (44.3%), and glycodeoxycholic acid (29.7%) probably due to the presence of the cbh and gnlE genes which form an operon (start: 119573 and end: 123812). Low BSH activity was determined intracellularly (<7%), particularly in glycocholic acid; no intracellular activity was shown. B. longum LBUX23 showed antioxidant effects in DPPH radical, mainly in intact cells (27.4%). In the case of hydroxyl radical scavenging capacity, cell debris showed the highest reduction (72.5%). In the cell-free extract, superoxide anion radical scavenging capacity was higher (90.5%). The genome of B. longum LBUX23 contains PNPOx, AhpC, Bcp, trxA, and trxB genes, which could be involved in this activity. Regarding adherence, it showed adherence up to 5% to Caco-2 cells. B. longum LBUX23 showed in vitro potential probiotic properties, mainly in BSH activity and antioxidant capacity, which indicates that it could be a good candidate for antioxidant or anti-cholesterol tests using in vivo models.

20.
Rev Biol Trop ; 60(2): 599-609, 2012 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-23894932

RESUMO

Mites of the family Klinckowstroemiidae establish an association with beetles of the family Passalidae known as phoresy. In order to obtain information about this association, we analyzed the relationship between mites of the family Klinckowstroemiidae and beetles of the family Passalidae, as adult mites have been exclusively collected from host beetles. We examined 1 150 beetles collected in seven states of the Mexican Republic, and found 19 species of klinckowstroemiid mites associated with 168 passalids, that belong to 28 different species in 15 genera. Host specificity between species of both groups does not exist, as one species of passalid beetle can have several different symbionts; conversely, a given mite species can associate with passalid beetles of different species and even of different genera. This way, Odontotaenius zodiacus has been found associated with mites of seven species of the genus Klinckowstroemia. Besides, Klinckowstroemia valdezi is associated with five species of passalids. Furthermore, two and even three different species of mites have been found on one host beetle (synhospitality). The lack of congruence between the phylogenies of the mites and that of the beetles indicates that a process of co-adaptation by colonization is going on, because the association is due to the resources that passalid beetles can offer to the mites, like transportation, food and refuge. Since these resources are not host-specific, the klinckowstroemiid mites can climb onto virtually any species of passalid beetles occurring on the same habitat.


Assuntos
Adaptação Fisiológica , Besouros/parasitologia , Especificidade de Hospedeiro , Ácaros/fisiologia , Simbiose , Animais , Besouros/classificação , Ácaros/classificação
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