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1.
Fish Physiol Biochem ; 50(2): 617-633, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38175338

RESUMO

Exposure to high temperatures induces changes in fish respiration, resulting in an increased production of reactive oxygen species. This, in turn, affects the enzymatic and non-enzymatic components of antioxidant defenses, which are essential for mitigating cellular stress. Rhamdia voulezi, an economically important fish species endemic to Brazil's Iguaçu River, served as the subject of our study. Our goal was to assess enzymatic antioxidant biomarkers (superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase, glutathione reductase, glucose-6-phosphate dehydrogenase), non-protein thiol levels (reduced glutathione), and markers of oxidative damage (lipoperoxidation and carbonylation) in the liver, gills, and kidneys of R. voulezi after acute exposure to high temperatures (31°C) for 2, 6, 12, 24, and 96 h. Control groups were maintained at 21°C. Our findings revealed that the liver exhibited increased superoxide dismutase levels up to 12 h and elevated glutathione S-transferase levels at 12 and 96 h at 31°C. In the gills, superoxide dismutase levels increased up to 24 h, along with increased lipoperoxidation at 2, 6, 12, and 96 h of exposure to high temperatures. The kidneys responded to heat stress at 12 h, with an increase in superoxide dismutase and catalase activity, and lipid peroxidation was observed at 2 and 6 h at 31°C. The three tissues evaluated responded differently to heat stress, with the liver demonstrating greater physiological adjustment to high temperatures. The intricate interplay of various antioxidant defense biomarkers and oxidative damage suggests the presence of oxidative stress in R. voulezi when exposed to high temperatures.


Assuntos
Antioxidantes , Peixes-Gato , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Temperatura , Estresse Oxidativo/fisiologia , Glutationa/metabolismo , Peixes-Gato/metabolismo , Superóxido Dismutase/metabolismo , Biomarcadores/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Brânquias/metabolismo , Peroxidação de Lipídeos
2.
New Phytol ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38009528

RESUMO

Variations in arbuscular mycorrhizae (AM) effects on plant growth (MGR) are commonly assumed to result from cost : benefit balances, with C as the cost and, most frequently, P as the benefit. The trade-balance model (TBM) adopts these assumptions and hypothesizes that mycorrhizal benefit depends on C : N : P stoichiometry. Although widely accepted, the TBM has not been experimentally tested. We isolated the parameters included in the TBM and tested these assumptions using it as framework. Oryza sativa plants were supplied with different N : P ratios at low light level, establishing different C : P and C : N exchange rates, and C, N or P limitation. MGR and effects on nutrient uptake, %M, ERM, photosynthesis and shoot starch were measured. C distribution to AM fungi played no role in MGR, and N was essential for all AM effects, including on P nutrition. C distribution to AM and MGR varied with the limiting nutrient (N or P), and evidence of extensive interplay between N and P was observed. The TBM was not confirmed. The results agreed with the exchange of surplus resources and source-sink regulation of resource distribution among plants and AMF. Rather than depending on exchange rates, resource exchange may simply obey both symbiont needs, not requiring further regulation.

3.
Appl Microbiol Biotechnol ; 107(17): 5281-5300, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37410135

RESUMO

Perennial grasses are potentially abundant sources of biomass for biorefineries, which can produce high yields with low input requirements, and many added environmental benefits. However, perennial grasses are highly recalcitrant to biodegradation and may require pretreatment before undergoing many biorefining pathways. Microbial pretreatment uses the ability of microorganisms or their enzymes to deconstruct plant biomass and enhance its biodegradability. This process can enhance the enzymatic digestibility of perennial grasses, enabling saccharification with cellulolytic enzymes to produce fermentable sugars and derived fermentation products. Similarly, microbial pretreatment can increase the methanation rate when the grasses are used to produce biogas through anaerobic digestion. Microorganisms can also increase the digestibility of the grasses to improve their quality as animal feed, enhance the properties of grass pellets, and improve biomass thermochemical conversion. Metabolites produced by fungi or bacteria during microbial pretreatment, such as ligninolytic and cellulolytic enzymes, can be further recovered as added-value products. Additionally, the action of the microorganisms can release chemicals with commercialization potential, such as hydroxycinnamic acids and oligosaccharides, from the grasses. This review explores the recent advances and remaining challenges in using microbial pretreatment for perennial grasses with the goal of obtaining added-value products through biorefining. It emphasizes recent trends in microbial pretreatment such as the use of microorganisms as part of microbial consortia or in unsterilized systems, the use and development of microorganisms and consortia capable of performing more than one biorefining step, and the use of cell-free systems based on microbial enzymes. KEY POINTS: • Microorganisms or enzymes can reduce the recalcitrance of grasses for biorefining • Microbial pretreatment effectiveness depends on the grass-microbe interaction • Microbial pretreatment can generate value added co-products to enhance feasibility.


Assuntos
Lignina , Poaceae , Animais , Lignina/química , Fermentação , Biocombustíveis , Biomassa
4.
Eur J Pediatr ; 182(3): 1403-1415, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36680578

RESUMO

The objectives of this study were to verify, first, if arterial stiffness indices can discriminate between obese and healthy children. Second, to evaluate arterial stiffness index predictors and hemodynamic parameters in obese children. Arterial stiffness indices evaluated were pulse wave velocity (PWV), central systolic blood pressure (SBPc), and central pulse pressure (PPc). A cross-sectional, descriptive, comparative study design was used. The sample consisted of 78 normal-weight children (8.1 ± 1.96 years) and 58 obese children (9.0 ± 1.87 years). PWV, PPc, and SBPc were significantly higher in the group of obese children than in the control group. The ROC curve analysis showed that maximum PWV and SBPc sensitivity and specificity in differentiating obese from non-obese children occurred at 4.09 m/s and 86.17 mmHg, respectively. PPc did not exhibit a discriminatory capacity between the two groups. Peripheral systolic blood pressure (SBPp), peripheral pulse pressure (PPp), and PPc (R2 = 0.98) were predictors of increased PWV. Augmentation pressure, PPp, and reflection coefficient (R2 = 0.873) were predictors of PPc. Age, augmentation index, total vascular resistance, cardiac index, and mean fat percentage (R2 = 0.801) were predictors of SBPc. CONCLUSION: This study shows for the first time that PWV > 4.09 m/s and SBPc > 86.17 mmHg are cut-off points associated with a higher risk of obesity. These results indicate that the simple, rapid, and noninvasive measurement of arterial stiffness adds prognostic information regarding cardiovascular risk, in addition to increased body mass index. WHAT IS KNOWN: • Overweight and obesity are strongly associated with comorbidities que contribute to the development of cardiovascular diseases. WHAT IS NEW: • This is the first study to show that PWV and SBPc can discriminate obese from non-obese children. These results show that, in addition to an increased BMI, a simple, rapid, and noninvasive measurement of arterial stiffness adds prognostic information on cardiovascular risk.


Assuntos
Rigidez Vascular , Humanos , Criança , Pressão Sanguínea/fisiologia , Rigidez Vascular/fisiologia , Análise de Onda de Pulso , Estudos Transversais , Obesidade/complicações
5.
Sensors (Basel) ; 23(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37687792

RESUMO

Green Chemistry is a vital and crucial instrument in achieving pollution control, and it plays an important role in helping society reach the Sustainable Development Goals (SDGs). NIR (near-infrared spectroscopy) has been utilized as an alternate technique for molecular identification, making the process faster and less expensive. Near-infrared diffuse reflectance spectroscopy and Machine Learning (ML) algorithms were utilized in this study to construct identification and classification models of bacteria such as Escherichia coli, Salmonella enteritidis, Enterococcus faecalis and Listeria monocytogenes. Furthermore, divide these bacteria into Gram-negative and Gram-positive groups. The green and quick approach was created by combining NIR spectroscopy with a diffuse reflectance accessory. Using infrared spectral data and ML techniques such as principal component analysis (PCA), hierarchical cluster analysis (HCA) and K-Nearest Neighbor (KNN), It was feasible to accomplish the identification and classification of four bacteria and classify these bacteria into two groups: Gram-positive and Gram-negative, with 100% accuracy. We may conclude that our study has a high potential for bacterial identification and classification, as well as being consistent with global policies of sustainable development and green analytical chemistry.


Assuntos
Algoritmos , Espectroscopia de Luz Próxima ao Infravermelho , Bactérias , Química Analítica , Escherichia coli , Aprendizado de Máquina
6.
Eur J Dent Educ ; 27(3): 633-639, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35997548

RESUMO

INTRODUCTION: Dentists usually refer to difficulties in performing the diagnosis of oral mucosal lesions. This may be attributed to limited access to theoretical lectures and practical training on this subject along the graduation course. The primary aim of this cross-sectional study was to verify if there is an association between the perception of time dedicated to lectures/training and oral diagnosis abilities in oral medicine. The secondary aim was to evaluate the association between self--confidence to perform oral mucosal lesions diagnosis and performance in a diagnostic abilities test. MATERIALS AND METHODS: The sample comprised 36 final-year dental students of a South-Brazilian dental school. The participants answered a questionnaire on their perception of time dedicated to lectures on oral medicine along the course (sufficient or insufficient) and their self-confidence to diagnose oral mucosal lesions or oral cancer (yes or not). The students were also submitted to a diagnostic abilities test based on 30 clinical photos of oral lesions, which should be classified as benign, potentially malignant or malignant. Moreover, the participants had to inform their clinical impression for each case. Finally, the participants informed their decision making for the case (refer the patient to a specialist or not). RESULTS: Students with higher self-confidence showed a higher percentage of correct answers on classification of the nature of lesions (81.1% vs. 68.5%, p = .03, teste t de Student) and on their clinical impression (66.3% vs. 41.7%, p < .01, Student's t-test). The perception of time dedicated to theoretical lectures on oral medicine as sufficient did not influence the students' diagnostic abilities (p > .05, Student's t-test) CONCLUSION: It may be concluded that self-confidence to diagnose oral lesions is associated with dental students' diagnostic abilities.


Assuntos
Educação em Odontologia , Estudantes de Odontologia , Humanos , Estudos Transversais , Autoimagem , Brasil
7.
Cerebellum ; 20(2): 186-202, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33098550

RESUMO

Thiamine deficiency is associated with cerebellar dysfunction; however, the consequences of thiamine deficiency on the electrophysiological properties of cerebellar Purkinje cells are poorly understood. Here, we evaluated these parameters in brain slices containing cerebellar vermis. Adult mice were maintained for 12-13 days on a thiamine-free diet coupled with daily injections of pyrithiamine, an inhibitor of thiamine phosphorylation. Morphological analysis revealed a 20% reduction in Purkinje cell and nuclear volume in thiamine-deficient animals compared to feeding-matched controls, with no reduction in cell count. Under whole-cell current clamp, thiamine-deficient Purkinje cells required significantly less current injection to fire an action potential. This reduction in rheobase was not due to a change in voltage threshold. Rather, thiamine-deficient neurons presented significantly higher input resistance specifically in the voltage range just below threshold, which increases their sensitivity to current at these critical membrane potentials. In addition, thiamine deficiency caused a significant decrease in the amplitude of the action potential afterhyperpolarization, broadened the action potential, and decreased the current threshold for depolarization block. When thiamine-deficient animals were allowed to recover for 1 week on a normal diet, rheobase, threshold, action potential half-width, and depolarization block threshold were no longer different from controls. We conclude that thiamine deficiency causes significant but reversible changes to the electrophysiology properties of Purkinje cells prior to pathological morphological alterations or cell loss. Thus, the data obtained in the present study indicate that increased excitability of Purkinje cells may represent a leading indicator of cerebellar dysfunction caused by lack of thiamine.


Assuntos
Células de Purkinje/patologia , Deficiência de Tiamina/patologia , Deficiência de Tiamina/fisiopatologia , Potenciais de Ação/fisiologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos , Técnicas de Patch-Clamp
8.
Biotechnol Lett ; 43(4): 835-844, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33386496

RESUMO

OBJECTIVES: The co-encapsulation of bioactive peptides obtained from degradation of chicken feathers and flexirubin-type pigment produced by Chryseobacterium sp. kr6 into phosphatidylcholine liposomes was investigated. RESULTS: Control empty liposomes showed mean diameter of 168.5 nm, varying to 185.4, 102.0 and 98.5 nm after the encapsulation of peptides, pigment and their co-encapsulation, respectively. Control liposomes presented zeta potential of - 20.9 mV, while the formulations containing the bioactive compounds showed values of - 30 mV or higher in magnitude. Infrared analysis revealed typical spectra for phosphatidylcholine, suggesting that no new chemical bonds were formed after encapsulation. ABTS radical scavenging assay showed that the antioxidant activity of the compounds was maintained after encapsulation. CONCLUSIONS: Feather waste can be a valuable substrate for simultaneous production of antioxidant peptides and pigment by Chryseobacterium sp. kr6, and their encapsulation into liposomes may be a suitable alternative for delivery of these natural antioxidants.


Assuntos
Antioxidantes/química , Chryseobacterium/crescimento & desenvolvimento , Plumas/microbiologia , Polienos/química , Animais , Antioxidantes/farmacologia , Biotransformação , Cápsulas , Chryseobacterium/metabolismo , Corantes/química , Composição de Medicamentos , Plumas/química , Lipossomos/química , Tamanho da Partícula , Fosfatidilcolinas/química
9.
An Acad Bras Cienc ; 93(3): e20191269, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34287454

RESUMO

Wetlands are ecosystems rich in biodiversity and their ecological importance is recognized worldwide. Sediment samples were subjected to physical-chemical analysis and organic carbon content varied from 3.0% to 4.8%, the clay between 32 and 40%, silt with 41% and 43%, sand coarse varied between 6 and 11% and fine sand between 7 and 16%. The nitrogen values ​​varied from 0.25% to 0.48%, the pH from 5.4 to 7.5 and the humidity ​​varied from 44 to 56%. The selected isolates were evaluated for enzymatic properties and 64% showed positive results for amylase, 16% for gelatinase, 37% for lipase, 91% for protease and 2.7% for inulinase. Six bacterial isolates were selected for the overlapping assay and Bacillus sp. sed 2.2 showed inhibitory activity against Corynebacterium fimi NCTC 7547, and the antimicrobial substance was partially purified. The characterization of the substance was carried and the substance was stable at 100° C for up to 10 minutes and sensitive to the enzymes papain and trypsin. This substance was active against some species of Listeria, including Listeria monocytogenes ATCC 7644. The microorganims obtained from sediment samples were important sources of bioactive compounds, including enzymes and peptides, being a source of bioactive compounds to be studied.


Assuntos
Bacillus , Listeria monocytogenes , Brasil , Ecossistema , Sedimentos Geológicos , Áreas Alagadas
10.
An Acad Bras Cienc ; 93(suppl 4): e20201820, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34730619

RESUMO

Bacteria of the genus Bacillus sp. present the potential for inhibiting various pathogens, making them a promising starting point in the search for new antimicrobial substances. In this study, bacteria were isolated from sediment samples from humid areas of a Natural Conservation Unit in the state of Rio Grande do Sul, Brazil. The isolate Bacillus sp. sed 1.4 was selected for production of antimicrobial activity, and was characterized by MALDI-TOF and 16S rDNA sequencing. Phylogenetic analysis showed that Bacillus sed 1.4 was closely related to Bacillus altitudinis and Bacillus pumilus. The cell-free supernatant was partially purified using ammonium sulfate precipitation, gel filtration chromatography (Sephadex G-200) and an ultrafiltration membrane. Partial purification resulted in specific activity of 769.23 AU/mg, with a molecular mass of approximately 148 kDa. This antimicrobial substance showed stability at 100°C for 5 min, and was inactivated by proteolytic enzymes. An antimicrobial effect against Listeria species was observed. Considering the importance of the Listeria genus in the area of food safety, this antimicrobial activity should be further explored, specifically in the field of dairy products and with a focus on food biopreservation studies.


Assuntos
Anti-Infecciosos , Bacillus , Concentração de Íons de Hidrogênio , Filogenia , Áreas Alagadas
11.
Synapse ; 74(3): e22137, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31584700

RESUMO

We examined effects of Group I metabotropic glutamate receptors on the excitability of mouse medial nucleus of the trapezoid body (MNTB) neurons. The selective agonist, S-3,5-dihydroxyphenylglycine (DHPG), evoked a dose-dependent depolarization of the resting potential, increased membrane resistance, increased sag depolarization, and promoted rebound action potential firing. Under voltage-clamp, DHPG evoked an inward current, referred to as IDHPG , which was developmentally stable through postnatal day P56. IDHPG had low temperature dependence in the range 25-34°C, consistent with a channel mechanism. However, the I-V relationship took the form of an inverted U that did not reverse at the calculated Nernst potential for K+ or Cl- . Thus, it is likely that more than one ion type contributes to IDHPG and the mix may be voltage dependent. IDHPG was resistant to the Na+ channel blockers tetrodotoxin and amiloride, and to inhibitors of iGluR (CNQX and MK801). IDHPG was inhibited 21% by Ba2+ (500 µM), 60% by ZD7288 (100 µM) and 73% when the two antagonists were applied together, suggesting that KIR channels and HCN channels contribute to the current. Voltage clamp measurements of IH indicated a small (6%) increase in Gmax by DHPG with no change in the voltage dependence. DHPG reduced action potential rheobase and reduced the number of post-synaptic AP failures during high frequency stimulation of the calyx of Held. Thus, activation of post-synaptic Group I mGlu receptors modifies the excitability of MNTB neurons and contributes to the reliability of high frequency firing in this auditory relay nucleus.


Assuntos
Potenciais de Ação , Fármacos Atuantes sobre Aminoácidos Excitatórios/farmacologia , Receptores de Glutamato Metabotrópico/metabolismo , Potenciais Sinápticos , Corpo Trapezoide/metabolismo , 6-Ciano-7-nitroquinoxalina-2,3-diona/farmacologia , Amilorida/farmacologia , Animais , Maleato de Dizocilpina/farmacologia , Feminino , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/antagonistas & inibidores , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Masculino , Metoxi-Hidroxifenilglicol/análogos & derivados , Metoxi-Hidroxifenilglicol/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/fisiologia , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio Corretores do Fluxo de Internalização/antagonistas & inibidores , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Pirimidinas/farmacologia , Receptores de Glutamato Metabotrópico/agonistas , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Bloqueadores dos Canais de Sódio/farmacologia , Tetrodotoxina/farmacologia , Corpo Trapezoide/citologia , Corpo Trapezoide/efeitos dos fármacos , Corpo Trapezoide/fisiologia
12.
Proc Natl Acad Sci U S A ; 114(10): E1857-E1865, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28202723

RESUMO

Voltage-gated sodium channels (Navs) play crucial roles in excitable cells. Although vertebrate Nav function has been extensively studied, the detailed structural basis for voltage-dependent gating mechanisms remain obscure. We have assessed the structural changes of the Nav voltage sensor domain using lanthanide-based resonance energy transfer (LRET) between the rat skeletal muscle voltage-gated sodium channel (Nav1.4) and fluorescently labeled Nav1.4-targeting toxins. We generated donor constructs with genetically encoded lanthanide-binding tags (LBTs) inserted at the extracellular end of the S4 segment of each domain (with a single LBT per construct). Three different Bodipy-labeled, Nav1.4-targeting toxins were synthesized as acceptors: ß-scorpion toxin (Ts1)-Bodipy, KIIIA-Bodipy, and GIIIA-Bodipy analogs. Functional Nav-LBT channels expressed in Xenopus oocytes were voltage-clamped, and distinct LRET signals were obtained in the resting and slow inactivated states. Intramolecular distances computed from the LRET signals define a geometrical map of Nav1.4 with the bound toxins, and reveal voltage-dependent structural changes related to channel gating.


Assuntos
Transferência de Energia/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Proteínas Musculares/química , Canais de Sódio/química , Canais de Sódio Disparados por Voltagem/efeitos dos fármacos , Animais , Sítios de Ligação/efeitos dos fármacos , Compostos de Boro/química , Cinética , Elementos da Série dos Lantanídeos/química , Músculo Esquelético/química , Músculo Esquelético/efeitos dos fármacos , Oócitos/química , Oócitos/efeitos dos fármacos , Técnicas de Patch-Clamp , Ratos , Venenos de Escorpião/química , Venenos de Escorpião/farmacologia , Canais de Sódio Disparados por Voltagem/genética , Xenopus/genética
13.
Malar J ; 18(1): 345, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601226

RESUMO

BACKGROUND: Malaria is a public health problem in the Brazilian Amazon region. In integrated vector management for malaria (anopheline) control, indoor residual spraying (IRS) represents one of the main tools in the basic strategy applied in the Amazonian states. It is essential to understand the residual efficacy of insecticides on different surfaces to determine spray cycles, ensure their rational use, and prevent wastage. This study aimed to evaluate the residual efficacy of six insecticide formulations used in the National Malaria Control Programme on four different types of walls in a field simulation at a "test house". METHODS: The tests were performed as a field-simulating evaluation at a "test house" built in the municipality of Macapá. Six insecticide formulations comprising four pyrethroids, a carbamate, and an organophosphate were used, and evaluated when applied on different wall surfaces: painted wood, unpainted wood, plastered cement, and unplastered cement. The insecticides were applied to the interior walls of the "test house" by a trained technician. RESULTS: In the bioassays performed with pyrethroids, deltamethrin water-dispersible granules (WG) performed particularly well, presenting residual bioefficacy of 8 months on both wood surfaces after the IRS, whereas alpha-cypermethrin suspension concentrate (SC) and etofenprox wettable powder (WP) demonstrated residual bioefficacy of 4 months on at least one of the wood surfaces; however, the pyrethroid lambda-cyhalothrin WP showed a low residual bioefficacy (< 3 months) on all tested surfaces, demonstrating its inefficiency for areas with a long transmission cycle of malaria. For the carbamate-bendiocarb WP, residual bioefficacy for 3 months was achieved only on wood surfaces. In general, the organophosphate pirimifos-methyl capsule suspension (CS) demonstrated the best result, with a mortality rate < 80% over a period of 6 months on all surfaces tested. CONCLUSION: Insecticide efficiency varies among different types of surface; therefore, a "test house" is a valuable evaluation tool. This work highlights the usefulness of associating the residual efficacy of insecticides on the surfaces commonly found in houses in endemic areas, together with knowledge about the transmission cycle duration of the transmission cycle and the insecticide susceptibility of the vector. This association helps in the decision-making for the malaria control intervention regarding.


Assuntos
Anopheles , Inseticidas , Malária/prevenção & controle , Controle de Mosquitos , Mosquitos Vetores , Animais , Brasil , Habitação
14.
Public Health Nutr ; 22(5): 776-784, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30587257

RESUMO

OBJECTIVE: The Brazilian Household Food Insecurity Measurement Scale (EBIA) has eight general/adult items applied in all households and six additional items exclusively asked in households with children and/or adolescents (HHCA). Continuing an investigation programme on the adequacy of model-based cut-off points for EBIA, the present study aims to: (i) explore the capacity of properly stratifying HHCA according to food insecurity (FI) severity level by applying only the eight 'generic' items; and (ii) compare it against the fourteen-item scale. DESIGN: Latent class factor analysis (LCFA) models were applied to the answers to the eight general/adult items to identify latent groups corresponding to FI levels and optimal group-separating cut-off points. Analyses involved a thorough classification agreement evaluation and were performed at the national level and by macro-regions. SETTING: Data derived from the cross-sectional Brazilian National Household Sample Survey of 2013. PARTICIPANTS: A nationally representative sample of 116 543 households. RESULTS: In all households and investigated domains, LCFA detected four distinct household food (in)security groups (food security and three levels of severity of FI) and the same set of cut-off points (1/2, 4/5 and 6/7). Misclassification in the aggregate data was 0·66 % in adult-only households and 1·06 % in HHCA. Comparison of the scale reduced to eight items with the 'original' fourteen-item scale demonstrated consistency in the classification. In HHCA, the agreement between both classifications was 96·2 %. CONCLUSIONS: Results indicate the eight 'generic' items in HHCA can be reliably used when it is not possible to apply the fourteen-item scale.

15.
Oral Dis ; 25(8): 1897-1905, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31332880

RESUMO

OBJECTIVES: YouTube™ has become a widely used source of health information. This cross-sectional study aimed to analyze the quality of English language videos on oral leukoplakia available on YouTube™. MATERIALS AND METHODS: A YouTube™ search for oral leukoplakia was performed, leading to 1,690 videos. The first 100 results were examined for exclusion criteria, yielding 28 videos. The source, duration, views, likes, and dislikes of each video were recorded. Two oral medicine residents scored the videos for visibility, popularity, quality, utility, and reliability. RESULTS: Videos were categorized into two groups: independent users or company advertisements (n = 21) and professional organizations or government agencies (n = 5). Analysis showed that, in general, videos were of low quality, usefulness, and reliability. Higher quality videos had more likes (p < .05, Mann-Whitney test). More reliable videos received more likes and presented a higher viewing rate and interaction index (p < .05, Mann-Whitney test). CONCLUSIONS: There are few high-quality videos about oral leukoplakia on YouTube™. Oral medicine professionals and students should attempt to correct this deficit, as they are the holders of evidence-based knowledge and clinical experience.


Assuntos
Informação de Saúde ao Consumidor , Disseminação de Informação/métodos , Leucoplasia Oral , Mídias Sociais , Estudos Transversais , Humanos , Reprodutibilidade dos Testes , Gravação em Vídeo
16.
Neurobiol Dis ; 115: 115-126, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29627580

RESUMO

Here we report a gain in function for mutant (mt) superoxide dismutase I (SOD1), a cause of familial amyotrophic lateral sclerosis (FALS), wherein small soluble oligomers of mtSOD1 acquire a membrane toxicity. Phosphatidylglycerol (PG) lipid domains are selectively targeted, which could result in membrane damage or "toxic channels" becoming active in the bilayer. This PG-selective SOD1-mediated membrane toxicity is largely reversible in vitro by a widely-available FDA-approved surfactant and membrane-stabilizer P188. Treatment of G93ASOD1 transgenic mice with P188 significantly delayed symptoms onset, extended survival and decreased motoneuron death. The use of P188 or an analogue, which targets mtSOD1 misfolding-induced membrane toxicity, may provide a new direction for ALS treatment.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/genética , Membrana Celular/fisiologia , Mutação/fisiologia , Poloxâmero/uso terapêutico , Superóxido Dismutase-1/genética , Esclerose Lateral Amiotrófica/patologia , Animais , Membrana Celular/efeitos dos fármacos , Membrana Celular/patologia , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Mutação/efeitos dos fármacos , Poloxâmero/farmacologia , Tensoativos/farmacologia , Tensoativos/uso terapêutico
17.
J Sex Marital Ther ; 44(2): 149-158, 2018 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-28569599

RESUMO

Casual sex has become a common experience for many university students. Therefore, it is necessary to have instruments and studies that analyze youth's orientation toward sociosexuality. The SOI-R assesses sociosexual behavior, attitudes toward sociosexuality, and the desire for relationships without commitment with just nine items. The goal of this study was to validate the Spanish version of the SOI-R, to improve the scale, and to contribute evidence of the utility of the Sociosexual Desire subscale. Participants were 839 heterosexual university students of both sexes, aged between 18 and 26, who completed a battery of online questionnaires. The internal structure of the SOI-R revealed the three proposed theoretical dimensions, with medium to low relationships between factors. The instrument has measurement invariance with regards to sex and age. The Spanish version of the SOI-R had adequate levels of reliability. The modification of the first item of the scale is suggested, as well as the relevance of assessing sociosexual desire as an independent construct. The relation between sociosexuality and other sociodemographic and psychosocial variables was also analyzed. The discussion highlights the need for research to determine youth's sociosexual orientation and patterns of casual sex.


Assuntos
Comportamento Sexual/psicologia , Comportamento Social , Inquéritos e Questionários/normas , Adulto , Feminino , Identidade de Gênero , Humanos , Individualidade , Relações Interpessoais , Masculino , Inventário de Personalidade/estatística & dados numéricos , Reprodutibilidade dos Testes , Espanha , Adulto Jovem
18.
Parasitology ; 145(8): 1065-1074, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29157317

RESUMO

Leishmaniasis is a widely spread and zoonotic disease with serious problems as low effectiveness of drugs, emergence of parasite resistance and severe adverse reactions. In recent years, considerable attention has been given to secondary metabolites produced by Photorhabdus luminescens, an entomopathogenic bacterium. Here, we assessed the leishmanicidal activity of P. luminescens culture fluids. Initially, promastigotes of Leishmania amazonensis were incubated with cell free conditioned medium of P. luminescens and parasite survival was monitored. Different pre-treatments of the conditioned medium revealed that the leishmanicidal activity is due to a secreted peptide smaller than 3 kDa. The Photorhabdus-derived leishmanicidal toxin (PLT) was enriched from conditioned medium and its effect on mitochondrial membrane potential of promastigotes, was determined. Moreover, the biological activity of PLT against amastigotes was evaluated. PLT inhibited the parasite growth and showed significant leishmanicidal activity against promastigote and amastigotes of L. amazonensis. PLT also caused mitochondrial dysfunction in parasites, but low toxicity to mammalian cell and human erythrocytes. Moreover, the anti-amastigote activity was independent of nitric oxide production. In summary, our results highlight that P. luminescens secretes Leishmania-toxic peptide(s) that are promising novel drugs for therapy against leishmaniasis.


Assuntos
Meios de Cultivo Condicionados/farmacologia , Descoberta de Drogas , Leishmania mexicana/efeitos dos fármacos , Peptídeos/química , Photorhabdus/química , Animais , Meios de Cultivo Condicionados/química , Eritrócitos/efeitos dos fármacos , Humanos , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Leishmania mexicana/crescimento & desenvolvimento , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Óxido Nítrico/metabolismo , Peptídeos/farmacologia , Photorhabdus/patogenicidade , Metabolismo Secundário
19.
An Acad Bras Cienc ; 90(1): 73-84, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29424388

RESUMO

The adhesion ability of bacteria to abiotic surfaces has important implications in food industries, because these organisms can survive for long periods through the biofilm formation. They can be transferred from one place to another in the industry causing contamination of the food processing environment. In this study, the antibacterial and antibiofilm activities of the antimicrobial peptide P34, characterized as a bacteriocin-like substance (BLS P34) were tested against planktonic and sessile cells of Staphylococcus aureus and Enterococcus faecalis isolated from foods. The BLS P34 showed inhibitory effect against all planktonic cells of E. faecalis. The inhibition of biofilm formation and the eradication of pre-formed biofilm were evaluated with the crystal violet assay and with the reduction of 3-bromide [4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium. The BLS P34 promoted a reduction of percentage of adhered microbial cells on the surface, not being able to perform the complete elimination of biofilm formation. The metabolic activity of S. aureus biofilms decreased considerably between 41-95%. However, E. faecalis cells showed up metabolically stimulated. The BLS P34 has the potential antibiofilm for the species S. aureus. Studies suggest more detailed approaches to a better understanding of the interactions between the antimicrobial and bacterial cells within the biofilm structure.


Assuntos
Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Biofilmes/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Oligopeptídeos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Análise de Variância , Animais , Bacillus/isolamento & purificação , Bacillus/metabolismo , Aderência Bacteriana/efeitos dos fármacos , Bacteriocinas/isolamento & purificação , Biofilmes/crescimento & desenvolvimento , Caraciformes/microbiologia , Enterococcus faecalis/fisiologia , Formazans , Testes de Sensibilidade Microbiana , Oligopeptídeos/isolamento & purificação , Valores de Referência , Reprodutibilidade dos Testes , Staphylococcus aureus/fisiologia , Sais de Tetrazólio
20.
Int J Psychol ; 53(4): 253-260, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27480887

RESUMO

Dehumanization is reached through several approaches, including the attribute-based model of mind perception and the metaphor-based model of dehumanization. We performed two studies to find different (de)humanized images for three targets: Professional people, Evil people, and Lowest of the low. In Study 1, we examined dimensions of mind, expecting the last two categories to be dehumanized through denial of agency (Lowest of the low) or experience (Evil people), compared with humanized targets (Professional people). Study 2 aimed to distinguish these targets using metaphors. We predicted that Evil and Lowest of the low targets would suffer mechanistic and animalistic dehumanization, respectively; our predictions were confirmed, but the metaphor-based model nuanced these results: animalistic and mechanistic dehumanization were shown as overlapping rather than independent. Evil persons were perceived as "killing machines" and "predators." Finally, Lowest of the low were not animalized but considered human beings. We discuss possible interpretations.


Assuntos
Inteligência Artificial/ética , Desumanização , Percepção/ética , Adolescente , Adulto , Idoso , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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