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1.
Ultrason Sonochem ; 105: 106867, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38581799

RESUMO

In this initial study, the impact of thermosonication as an alternative to the traditional fusion in Brazilian cheese spread (Requeijão Cremoso) manufacture was investigated. The effect of ultrasound (US) power was evaluated considering various aspects such as gross composition, microstructure, texture, rheology, color, fatty acid composition, and volatile compounds. A 13 mm US probe operating at 20 kHz was used. The experiment involved different US power levels (200, 400, and 600 W) at 85 °C for 1 min, and results were compared to the conventional process in the same conditions (85 °C for 1 min, control treatment). The texture became softer as ultrasound power increased from 200 to 600 W, which was attributed to structural changes within the protein and lipid matrix. The color of the cheese spread also underwent noticeable changes for all US treatments, and treatment at 600 W resulted in increased lightness but reduced color intensity. Moreover, the fatty acid composition of the cheese spread showed variations with different US power, with samples treated at 600 W showing lower concentrations of saturated and unsaturated fatty acids, as well as lower atherogenicity and thrombogenicity indexes, indicating a potentially healthier product. Volatile compounds were also influenced by US, with less compounds being identified at higher powers, especially at 600 W. This could indicate possible degradation, which should be evaluated in further studies regarding US treatment effects on consumer perception. Hence, this initial work demonstrated that thermosonication might be interesting in the manufacture of Brazilian cheese spread, since it can be used to manipulate the texture, color and aroma of the product in order to improve its quality parameters.


Assuntos
Queijo , Queijo/análise , Sonicação/métodos , Brasil , Manipulação de Alimentos/métodos , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/análise , Ácidos Graxos/química , Cor , Temperatura
2.
J Neurosci ; 43(49): 8367-8384, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-37775301

RESUMO

The nuclear factor one (NFI) transcription factor genes Nfia, Nfib, and Nfix are all enriched in late-stage retinal progenitor cells, and their loss has been shown to retain these progenitors at the expense of later-generated retinal cell types. Whether they play any role in the specification of those later-generated fates is unknown, but the expression of one of these, Nfia, in a specific amacrine cell type may intimate such a role. Here, Nfia conditional knockout (Nfia-CKO) mice (both sexes) were assessed, finding a massive and largely selective absence of AII amacrine cells. There was, however, a partial reduction in type 2 cone bipolar cells (CBCs), being richly interconnected to AII cells. Counts of dying cells showed a significant increase in Nfia-CKO retinas at postnatal day (P)7, after AII cell numbers were already reduced but in advance of the loss of type 2 CBCs detected by P10. Those results suggest a role for Nfia in the specification of the AII amacrine cell fate and a dependency of the type 2 CBCs on them. Delaying the conditional loss of Nfia to the first postnatal week did not alter AII cell number nor differentiation, further suggesting that its role in AII cells is solely associated with their production. The physiological consequences of their loss were assessed using the ERG, finding the oscillatory potentials to be profoundly diminished. A slight reduction in the b-wave was also detected, attributed to an altered distribution of the terminals of rod bipolar cells, implicating a role of the AII amacrine cells in constraining their stratification.SIGNIFICANCE STATEMENT The transcription factor NFIA is shown to play a critical role in the specification of a single type of retinal amacrine cell, the AII cell. Using an Nfia-conditional knockout mouse to eliminate this population of retinal neurons, we demonstrate two selective bipolar cell dependencies on the AII cells; the terminals of rod bipolar cells become mis-stratified in the inner plexiform layer, and one type of cone bipolar cell undergoes enhanced cell death. The physiological consequence of this loss of the AII cells was also assessed, finding the cells to be a major contributor to the oscillatory potentials in the electroretinogram.


Assuntos
Células Amácrinas , Fatores de Transcrição NFI , Retina , Animais , Feminino , Masculino , Camundongos , Células Amácrinas/metabolismo , Eletrorretinografia , Fatores de Transcrição NFI/metabolismo , Retina/metabolismo , Células Bipolares da Retina , Fatores de Transcrição/metabolismo
3.
Eur Rev Med Pharmacol Sci ; 27(15): 7276-7288, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37606136

RESUMO

In Western countries, calcific aortic valve stenosis (CAS) is widely common, representing the third cause of death among cardiovascular diseases (CVD). The burden of CAS is high, with an increasing prevalence rate related to age. An efficient medical treatment, according to guidelines, lacks to prevent the development and to reduce the progression of CAS. In this context, due to the aging population and the lack of effective medical management, the prevalence is expected to double-triple within the next decades. In our review, we aim to provide an overview of the underlying mechanisms of pathogenesis and the current state of the art regarding pathophysiological insights and novel potential therapeutic targets.


Assuntos
Estenose da Valva Aórtica , Humanos , Idoso
4.
ACS Omega ; 8(28): 25610-25622, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37483177

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disorder that has no cure because its etiology is still unknown, and its main treatment is the administration of acetylcholinesterase (AChE) inhibitors. The study of the mechanism of action of this family of compounds is critical for the design of new more potent and specific inhibitors. In this work, we study the molecular basis of an uncompetitive inhibitor (compound 1, 2ß, 3α-dihydroxy-5α-cholestan-6-one disulfate), which we have proved to be a peripheral anionic site (PAS)-binding AChE inhibitor. The pipeline designed in this work is key to the development of other PAS inhibitors that not only inhibit the esterase action of the enzyme but could also modulate the non-cholinergic functions of AChE linked to the process of amylogenesis. Our studies showed that 1 inhibits the enzyme not simply by blocking the main gate but by an allosteric mechanism. A detailed and careful analysis of the ligand binding position and the protein dynamics, particularly regarding their secondary gates and active site, was necessary to conclude this. The same analysis was executed with an inactive analogue (compound 2, 2ß, 3α-dihydroxy-5α-cholestan-6-one). Our first computational results showed no differences in affinity to AChE between both steroids, making further analysis necessary. This work highlights the variables to be considered and develops a refined methodology, for the successful design of new potent dual-action drugs for AD, particularly PAS inhibitors, an attractive strategy to combat AD.

5.
Sensors (Basel) ; 23(11)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37299795

RESUMO

This work presents a multi-parameter optical fiber monitoring solution applied to an underground power distribution network. The monitoring system demonstrated herein uses Fiber Bragg Grating (FBG) sensors to measure multiple parameters, such as the distributed temperature of the power cable, external temperature and current of the transformers, liquid level, and intrusion in the underground manholes. To monitor partial discharges of cable connections, we used sensors that detect radio frequency signals. The system was characterized in the laboratory and tested in underground distribution networks. We present here the technical details of the laboratory characterization, system installation, and the results of 6 months of network monitoring. The data obtained for temperature sensors in the field tests show a thermal behavior depending on the day/night cycle and the season. The temperature levels measured on the conductors indicated that in high-temperature periods, the maximum current specified for the conductor must be reduced, according to the applied Brazilian standards. The other sensors detected other important events in the distribution network. All the sensors demonstrated their functionality and robustness in the distribution network, and the monitored data will allow the electric power system to have a safe operation, with optimized capacity and operating within tolerated electrical and thermal limits.


Assuntos
Líquidos Corporais , Humanos , Brasil , Fontes de Energia Elétrica , Eletricidade , Febre
6.
J Phys Condens Matter ; 35(34)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37160131

RESUMO

In this study, we examine Ni49Nb1Mn36In14(nom. at.%) magnetic shape memory alloy (MSMA) to illustrate the inverse magnetocaloric effect (MCE) using the fraction method. The magnetic entropy change,ΔSmag, was calculated with both, the fraction method and the thermomagnetic Maxwell relation. Our results demonstrate that there exists a large magnetization difference between field-cooling and field-heating histories in Ni49Nb1Mn36In14(nom. at.%) MSMA, which can be attributed to the pinning of lattice entropy and magnetic entropy, as it is well-known that the temperature and applied magnetic fields have an opposing effect on the total entropy change. In addition, we describe the inverse MCE and the contradictory roles on the total entropy change between the two stimuli via the fraction method.

7.
Front Immunol ; 14: 886601, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36960058

RESUMO

Introduction: Pulmonary fibrosis is a destructive, progressive disease that dramatically reduces life quality of patients, ultimately leading to death. Therapeutic regimens for pulmonary fibrosis have shown limited benefits, hence justifying the efforts to evaluate the outcome of alternative treatments. Methods: Using a mouse model of bleomycin (BLM)-induced lung fibrosis, in the current work we asked whether treatment with pro-resolution molecules, such as pro-resolving lipid mediators (SPMs) could ameliorate pulmonary fibrosis. To this end, we injected aspirin-triggered resolvin D1 (7S,8R,17R-trihydroxy-4Z,9E,11E,13Z,15E19Z-docosahexaenoic acid; ATRvD1; i.v.) 7 and 10 days after BLM (intratracheal) challenge and samples were two weeks later. Results and discussion: Assessment of outcome in the lung tissues revealed that ATRvD1 partially restored lung architecture, reduced leukocyte infiltration, and inhibited formation of interstitial edema. In addition, lung tissues from BLM-induced mice treated with ATRvD1 displayed reduced levels of TNF-α, MCP-1, IL-1-ß, and TGF-ß. Of further interest, ATRvD1 decreased lung tissue expression of MMP-9, without affecting TIMP-1. Highlighting the beneficial effects of ATRvD1, we found reduced deposition of collagen and fibronectin in the lung tissues. Congruent with the anti-fibrotic effects that ATRvD1 exerted in lung tissues, α-SMA expression was decreased, suggesting that myofibroblast differentiation was inhibited by ATRvD1. Turning to culture systems, we next showed that ATRvD1 impaired TGF-ß-induced fibroblast differentiation into myofibroblast. After showing that ATRvD1 hampered extracellular vesicles (EVs) release in the supernatants from TGF-ß-stimulated cultures of mouse macrophages, we verified that ATRvD1 also inhibited the release of EVs in the bronco-alveolar lavage (BAL) fluid of BLM-induced mice. Motivated by studies showing that BLM-induced lung fibrosis is linked to angiogenesis, we asked whether ATRvD1 could blunt BLM-induced angiogenesis in the hamster cheek pouch model (HCP). Indeed, our intravital microscopy studies confirmed that ATRvD1 abrogates BLM-induced angiogenesis. Collectively, our findings suggest that treatment of pulmonary fibrosis patients with ATRvD1 deserves to be explored as a therapeutic option in the clinical setting.


Assuntos
Fibrose Pulmonar , Humanos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/metabolismo , Aspirina/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Ácidos Docosa-Hexaenoicos/uso terapêutico , Pulmão/patologia , Bleomicina/farmacologia , Fator de Crescimento Transformador beta/metabolismo
8.
J Anim Physiol Anim Nutr (Berl) ; 107(2): 529-540, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35603976

RESUMO

Evaluation of the diet of the pig (Sus scrofa) in natural settings may provide new views on diet optimization for growth and development of commercially raised piglets under farm conditions. A field study was conducted to gain insight in the diet and stomach characteristics of feral piglets. Forty animals (body weight: 4.6 ± 1.37 kg) were collected from the Bahía Samborombón (Buenos Aires, Argentina). Stomachs were weighed after storage in formalin and the particle size distribution of their contents was determined by wet sieving. Diet items present in their stomachs were classified and their proportional weight and relative abundance was calculated. Based on their dentition, 5, 16 and 19 piglets were approximately 1, 3-6 and 6-16 weeks of age respectively. Vegetable matter (mainly 'leaves and stems') was predominantly present in 39 animals. It represented on average 83 ± 36.4% of total stomach contents by weight. The stomachs of 12 piglets contained curd and represented on average 16 ± 35.1% by weight. Other diet items were less abundant or absent. The proportion of stomach particles retained were 24%, 13%, 22%, 13% and 28% for sieves with mesh sizes of 2000, 1000, 420, 210 and <210 µm respectively. For comparison, we used data of farmed piglets of similar age and fed a nutrient-dense, finely ground diet. Feral piglets' relative empty stomach weights increased with age (p < 0.050), whereas this was not the case for farmed piglets. Relative stomach contents weight increased significantly with age only for farmed piglets (p < 0.050). We infer from our data that feral suckling piglets consumed a variety of non-milk items, mainly consisting of vegetable material with a coarse particle size from their first week in life onwards. Their diet is associated with an enhanced stomach development compared to those of farmed piglets.


Assuntos
Dieta , Conteúdo Gastrointestinal , Suínos , Animais , Fazendas , Dieta/veterinária , Estômago , Sus scrofa , Ração Animal/análise
9.
Nat Prod Res ; : 1-11, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36148610

RESUMO

Two new glycosylflavones, 6''-O-acetyl-8-C-ß-D-galactopyranosylchrysoeriol (1) and 8-C-ß-D-galactopyranosylchrysoeriol (2) were isolated from the methanol extract of the leaves of Ochna afzelii Oliv., along with four known compounds namely 8-C-ß-D-galactopyranosylapigenin (3), ochnaflavone (4), sitosterol-3-O-ß-D-glucopyranoside (5) and D-mannitol (6). Isolation was performed chromatographically and the structures of the purified compounds were elucidated by analyzing their spectroscopic and mass spectrometric data. The antibacterial activity of extract, fractions, and compounds 1 - 4 was evaluated using broth microdilution method against Gram-positive and Gram-negative bacteria while the antioxidant capacity was performed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the ferric reducing antioxidant power (FRAP) methods. The new flavones (1 and 2) displayed moderate antibacterial activities (MIC = 32 - 64 µg/mL) and weak antioxidant properties.

10.
Nat Prod Res ; 36(17): 4379-4387, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34694175

RESUMO

A phytochemical study of the methanol extract of the fruit of Maesa lanceolata resulted in the isolation of a new alkenylbenzoquinone (1), alongside the known compounds (Z)-2,5-dihydroxy-6-methyl-3-(pentadec-10'-enyl)-1,4-benzoquinone (2), 2,5-dihydroxy-6-methyl-3-(nonadec-14'-enyl)-1,4-benzoquinone (3), 2,5-dihydroxy-6-methyl-3-(tridecyl)-1,4-benzoquinone (4), (2S,3S,4R,2'R,9E)-[2'-hydroxytetraeicosanoyl]-2-aminooctadec-9-ene-1,3,4-triol (5), monopalmitin (glyceryl palmitate) (6), lupeol (7), and 3-O-(ß-D-glucopyranoside)-ß-sitosterol (8). The structures of the compounds were established by the means of spectroscopic (1 D- and 2 D-NMR) and spectrometric techniques (MS). The isolated compounds were assessed for their antibacterial, cytotoxic, and antiradical activities. Compound 2 showed moderate activity against Staphylococcus warneri (DSMZ 20036), while the other compounds were inactive. The two quinones 1 and 2 were significantly cytotoxic, with IC50 values of 0.005 µM and 12.5 µM respectively, and were weakly active towards DPPH radical (IC50 >250 µg/mL).


Assuntos
Frutas , Maesa , Antibacterianos/análise , Antibacterianos/farmacologia , Benzoquinonas/química , Frutas/química , Estrutura Molecular , Extratos Vegetais/química
11.
Motriz (Online) ; 28: e10220006022, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1406012

RESUMO

Abstract Aim: This review article aimed to search for studies that used SSG as an intervention in order to verify the effects of physical and tactical performance in young soccer players and to make a critical analysis in the literature of how small games are proposed, how they are controlled and how they affect the performance of soccer players in the short and medium term. Methods: In this narrative review, we searched four databases (PubMed, Scopus, Web of Science, and SPORTDiscus), in total, 242 studies were found. In the end, only eight studies were used in this review. Results: Four studies were comparisons between SSG and traditional methods; one study compared different types of SSG; one study compared the intensity of small-sided games with official games and another two made comparisons of physical performance between different categories. All the studies had as a central point to make comparisons in relation to the physical performance and none of them, longitudinally, evaluated the tactical performance using the SSG as an intervention. Conclusions: The use of SSG, mainly in 3×3 (dimensions between 20×25 m and 27×36 m) and 4×4 (30×35 m to 30×40 m) between 3 and 5 sessions per week for at least one month, seems to have beneficial effects concerning physical performance for young athletes. It was verified the scarcity of studies that approach the tactical performance with the use of SSG, in addition, some studies were unclear about the frequency of SSG types during the intervention time.

12.
Phys Chem Chem Phys ; 23(48): 27484-27497, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34873605

RESUMO

We report on single- and double-charge photofragment formation by synchrotron radiation, following C 1s core excitation and ionization and Cl 2p inner excitation and ionization of chlorobenzene, C6H5Cl. From a comparison of experimental near-edge X-ray absorption fine structure spectra and theoretical ab initio calculations, the nature of various core and inner shell transitions of the molecule and pure atomic features were identified. To shed light on the normal Auger processes following excitation or ionization of the molecule at the Cl 2p or C 1s sites, we addressed the induced ionic species formation. With energy resolved electron spectra and ion time-of-flight spectra coincidence measurements, the ionic species were correlated with binding energy regions and initial states of vacancies. We explored the formation of the molecular dication C6H5Cl2+, the analogue benzene dication C6H42+, and the singly charged species produced by single loss of a carbon atom, C5HnCl+. The appearance and intensities of the spectral features associated with these ionic species are shown to be strongly site selective and dependent on the energy ranges of the Auger electron emission. Unexpected intensities for the analogue double charged benzene C6H42+ ion were observed with fast Auger electrons. The transitions leading to C6H5Cl2+ were identified from the binding energy representation of high resolution electron energy spectra. Most C6H5Cl2+ ions decay into two singly charged moieties, but intermediate channels are opened leading to other heavy dicationic species, C6H42+ and C6H4Cl2+, the channel leading to the first of these being much more favored than the other.

13.
Int J Mol Sci ; 22(21)2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34769064

RESUMO

Novel strategies for the prevention and treatment of sepsis-associated acute kidney injury and its long-term outcomes have been required and remain a challenge in critical care medicine. Therapeutic strategies using lipid mediators, such as aspirin-triggered resolvin D1 (ATRvD1), can contribute to the resolution of acute and chronic inflammation. In this study, we examined the potential effect of ATRvD1 on long-term kidney dysfunction after severe sepsis. Fifteen days after cecal ligation and puncture (CLP), sepsis-surviving BALB/c mice were subjected to a tubulointerstitial injury through intraperitoneal injections of bovine serum albumin (BSA) for 7 days, called the subclinical acute kidney injury (subAKI) animal model. ATRvD1 treatment was performed right before BSA injections. On day 22 after CLP, the urinary protein/creatinine ratio (UPC), histologic parameters, fibrosis, cellular infiltration, apoptosis, inflammatory markers levels, and mRNA expression were determined. ATRvD1 treatment mitigated tubulointerstitial injury by reducing proteinuria excretion, the UPC ratio, the glomerular cell number, and extracellular matrix deposition. Pro-fibrotic markers, such as transforming growth factor ß (TGFß), type 3 collagen, and metalloproteinase (MMP)-3 and -9 were reduced after ATRvD1 administration. Post-septic mice treated with ATRvD1 were protected from the recruitment of IBA1+ cells. The interleukin-1ß (IL-1ß) levels were increased in the subAKI animal model, being attenuated by ATRvD1. Tumor necrosis factor-α (TNF-α), IL-10, and IL-4 mRNA expression were increased in the kidney of BSA-challenged post-septic mice, and it was also reduced after ATRvD1. These results suggest that ATRvD1 protects the kidney against a second insult such as BSA-induced tubulointerstitial injury and fibrosis by suppressing inflammatory and pro-fibrotic mediators in renal dysfunction after sepsis.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Aspirina/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Glomérulos Renais/efeitos dos fármacos , Sepse/tratamento farmacológico , Injúria Renal Aguda/induzido quimicamente , Albuminas/farmacologia , Animais , Biomarcadores/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Testes de Função Renal/métodos , Glomérulos Renais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteinúria/induzido quimicamente , Proteinúria/tratamento farmacológico , Proteinúria/metabolismo , RNA Mensageiro/metabolismo , Sepse/metabolismo
14.
Mol Pharmacol ; 100(5): 513-525, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34580163

RESUMO

Among ß-blockers that are clinically prescribed for heart failure, carvedilol is a first-choice agent with unique pharmacological properties. Carvedilol is distinct from other ß-blockers in its ability to elicit ß-arrestin-biased agonism, which has been suggested to underlie its cardioprotective effects. Augmenting the pharmacologic properties of carvedilol thus holds the promise of developing more efficacious and/or biased ß-blockers. We recently identified compound-6 (cmpd-6), the first small molecule positive allosteric modulator of the ß2-adrenergic receptor (ß2AR). Cmpd-6 is positively cooperative with orthosteric agonists at the ß2AR and enhances agonist-mediated transducer (G-protein and ß-arrestin) signaling in an unbiased manner. Here, we report that cmpd-6, quite unexpectedly, displays strong positive cooperativity only with carvedilol among a panel of structurally diverse ß-blockers. Cmpd-6 enhances the binding affinity of carvedilol for the ß2AR and augments its ability to competitively antagonize agonist-induced cAMP generation. Cmpd-6 potentiates ß-arrestin1- but not Gs-protein-mediated high-affinity binding of carvedilol at the ß2AR and ß-arrestin-mediated cellular functions in response to carvedilol including extracellular signal-regulated kinase phosphorylation, receptor endocytosis, and trafficking into lysosomes. Importantly, an analog of cmpd-6 that selectively retains positive cooperativity with carvedilol acts as a negative modulator of agonist-stimulated ß2AR signaling. These unprecedented cooperative properties of carvedilol and cmpd-6 have implications for fundamental understanding of G-protein-coupled receptor (GPCR) allosteric modulation, as well as for the development of more effective biased beta blockers and other GPCR therapeutics. SIGNIFICANCE STATEMENT: This study reports on the small molecule-mediated allosteric modulation of the ß-arrestin-biased ß-blocker, carvedilol. The small molecule, compound-6 (cmpd-6), displays an exclusive positive cooperativity with carvedilol among other ß-blockers and enhances the binding affinity of carvedilol for the ß2-adrenergic receptor. Cooperative effects of cmpd-6 augment the ß-blockade property of carvedilol while potentiating its ß-arrestin-mediated signaling functions. These findings have potential implications in advancing G-protein-coupled receptor allostery, developing biased therapeutics and remedying cardiovascular ailments.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Carvedilol/farmacologia , Receptores Adrenérgicos beta 2 , beta-Arrestinas/farmacologia , Antagonistas Adrenérgicos beta/química , Antagonistas Adrenérgicos beta/metabolismo , Regulação Alostérica/efeitos dos fármacos , Regulação Alostérica/fisiologia , Animais , Carvedilol/química , Carvedilol/metabolismo , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Receptores Adrenérgicos beta 2/metabolismo , Células Sf9 , beta-Arrestinas/química , beta-Arrestinas/metabolismo
15.
Molecules ; 26(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34443305

RESUMO

The local botanical Imperata cylindrica in Cameroon was investigated for its antibacterial potency. The methanol extract afforded a total of seven compounds, including five hitherto unreported compounds comprising three flavonoids (1-3) and two C-15 isoprenoid analogues (4 and 5) together with known derivatives (6 and 7). The novelty of the flavonoids was related to the presence of both methyl and prenyl groups. The potential origin of the methyl in the flavonoids is discussed, as well as the chemophenetic significance of our findings. Isolation was performed over repeated silica gel and Sephadex LH-20 column chromatography and the structures were elucidated by (NMR and MS). The crude methanol extract and isolated compounds showed considerable antibacterial potency against a panel of multi-drug resistant (MDR) bacterial strains. The best MIC values were obtained with compound (2) against S. aureus ATCC 25923 (32 µg/mL) and MRSA1 (16 µg/mL).


Assuntos
Antibacterianos/farmacologia , Flavonoides/farmacologia , Poaceae/química , Prenilação , Terpenos/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Flavonoides/química , Flavonoides/isolamento & purificação , Testes de Sensibilidade Microbiana , Espectroscopia de Prótons por Ressonância Magnética , Terpenos/química , Terpenos/isolamento & purificação
16.
Sci Justice ; 61(4): 378-383, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34172126

RESUMO

Latent fingermarks are important trace evidence found in crime scenes mainly used for identification purposes. Once deposited, the composition of samples changes over time influencing the efficacy of latent fingermark development methods. In this sense, the aims of this work were to characterize the fatty acid (FA) profile of sebaceous latent fingermarks by GC-FID and to preliminarily evaluate the development efficiency of enhancement methods (powder dusting, iodine fuming and silver nitrate method) in a 30-day period of aging under controlled parameters of temperature, photoperiod and humidity. Results showed that myristic (7.51 ± 0.76% - 13.39 ± 1.26%), palmitic (35.91 ± 1.07% - 40.81 ± 2.52%), stearic (6.67 ± 0.36% - 9.13 ± 0.36%) and oleic (18.08 ± 0.25% - 20.93 ± 0.26%) acid varied significantly (p < 0.05) over the 30-day period of analysis. Regarding development efficiency, fluorescent orange powder and the silver nitrate method also increased their efficacy to develop latent fingermarks over time while the iodine fuming method decreased its efficiency. Silver black powder had constant efficacy in the tested period. Changes in the constitution of sebaceous marks possibly influenced the development efficiency of enhancement techniques. This knowledge is important to better understand the kinetic of aging and its influence on the development method.


Assuntos
Iodo , Nitrato de Prata , Idoso , Corantes , Dermatoglifia , Humanos , Pós
17.
Org Biomol Chem ; 19(16): 3656-3664, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33908433

RESUMO

The first catalytic enantioselective aza-Cope rearrangement was reported in 2008 by Rueping et al. The reaction is catalyzed by a 1,1'-bi-2-naphthol-derived (BINOL-derived) phosphoric acid and achieved high yields and enantioselectivities (up to 97 : 3 er with 75% yield). This work utilizes Density Functional Theory to understand the mechanism of the reaction and explain the origins of the enantioselectivity. An extensive conformational search was carried out to explore the different activation modes by the catalyst and, the Transition State (TS) leading to the major product was found to be 1.3 kcal mol-1 lower in energy than the TS leading to the minor product. The origin of this stabilization was rationalized with NBO and NCI analysis: it was found that the major TS has a greater number of non-bonding interactions between the substrate and the catalyst, and shows stronger H-bond interactions between H atoms in the substrate and the O atoms in the phosphate group of the catalyst.

18.
Sensors (Basel) ; 21(2)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466683

RESUMO

In this work, we present the design, laboratory tests, and the field trial results of a power-over-fiber (PoF) low power instrument transformer (LPIT) for voltage and current measurements in the medium voltage distribution networks. The new proposed design of this power-over-fiber LPIT aims to overcome the drawbacks presented by the previous technologies, such as the continuous operation (measuring and data transmission) for a wide current range conducted in the medium voltage transmission lines, damage due to lightning strikes, accuracy dependency on vibration, position and temperatures. The LPIT attends the accuracy criteria of IEC 61869-10 and IEC 61869-11 in terms of current and voltage accuracy and it attends the practical criteria adopted by Utilities companies including voltage measurements without removing the coating of the covered conductors. The PoF based LPIT was developed to be applied at 11.9 kV, 13.8 kV, and 23.0 kV phase-to-phase nominal voltages, and in two current ranges 1.25-30 A and 37.5-900 A. The digital data transmission of current, voltage, and temperature from the sensing unit to the processing unit uses a special synchronism technique and it is performed by two 62.5 µm multimode fibers in 850 nm. The optical powering in 976 nm is also performed by one 62.5 µm multimode fiber from the processing unit to the sensor unit. We presented all details of the sensor design and its laboratory characterization in terms of accuracy and temperature correction. We also presented the results of field tests of the sensor made in two different conditions: in a standard distribution network and an experimental hybrid fiber/power distribution network. We believe that these studies aim to incorporate optical fiber and devices, digital technologies, communications systems in electrical systems driving their evolution.

19.
Artigo em Inglês | MEDLINE | ID: mdl-33076286

RESUMO

Although dating applications (apps) have become popular among young adults, there is a dearth of information regarding the sexual health implications among Brazilian college students. This study examined risky sexual behavior and attitudes of dating app users, based on their sex in Brazil's Legal Amazon. Three hundred and fifty-nine students reported their sociodemographic data, dating app use, and sexual behaviors and attitudes through self-administered questionnaires. Bivariate analyses and analysis of variance (ANOVA) with Bonferroni post-hoc tests were performed. Dating app use was reported by 238 (66.3%) subjects, most of whom had an encounter and sex with a casual partner. Women frequently requested condom use. Trust in one's partner or having repeated encounters were the main reasons for engaging in risky sexual behavior. Men had a greater number of sexual partners and less protective attitudes. Sexual health awareness by apps was not reported by 97% of women, and most of them were not tested for sexually transmitted infections. A positive attitude toward sexual health was not a predictor of safe sex. Important similarities and differences regarding risky sexual behaviors and attitudes were observed between the sexes, many of which correlated with increased sexual vulnerability during the sexual encounters arranged through the dating apps. This cross-sectional study supports efforts on sexual health promotion and sexual education implementation in the face of growing usage of apps among young adults for sexual matters.


Assuntos
Preservativos , Conhecimentos, Atitudes e Prática em Saúde , Comportamento Sexual , Estudantes , Atitude , Brasil , Estudos Transversais , Feminino , Humanos , Masculino , Parceiros Sexuais , Estudantes/psicologia , Inquéritos e Questionários , Adulto Jovem
20.
Sci Rep ; 10(1): 14211, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32848195

RESUMO

The giant magnetocaloric effect was quantified in CoMn1-xFexGe (x = 0.085-0.12) nom. at. % polycrystals across the high temperature hexagonal (P63/mmc) to low temperature orthorhombic (Pnma) phase transition via differential scanning calorimetry (DSC) and multiple (thermo) magnetization measurements. It was found that increasing Fe content led to the decrease of both the martensitic transformation temperature and entropy change ([Formula: see text]) at the point of the phase transition. Moreover, first-time magnetocaloric measurements resulted in irreproducible entropy change versus temperature diagrams, which was attributed to the release of internal pressure in bulk samples that disintegrated into powder upon transformation. CoMn1-xFexGe demonstrated larger magnetic field-induced entropy changes and giant magnetocaloric effect (MCE) compared to other CoMnGe alloys doped with Si, Sn, Ti, and Ga. However, the observed brittleness and apparent change in volume at the magnetic transition was posited to influence the material's potential for regenerative applications.

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