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1.
Genes Chromosomes Cancer ; 63(2): e23221, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38682608

RESUMO

Hereditary leiomyomatosis and renal cell cancer (HLRCC) is an autosomal dominant cancer predisposition syndrome characterized by cutaneous leiomyomas, uterine leiomyomas, and aggressive renal cancer. Germline variants in the fumarate hydratase (FH) gene predispose to HLRCC. Identifying germline pathogenic FH variants enables lifetime renal cancer screening and genetic testing for family members. In this report, we present a FH missense variant (c.1039T>C (p.S347P)), initially classified as a variant of uncertain significance. Clinical assessment, histopathological findings, molecular genetic studies, and enzymatic activity studies support the re-classification of the FH c.1039T>C variant to "pathogenic" based on ACMG/AMP criteria. Further insights into pathological recognition of FH-deficient renal cancer are discussed and should be recognized. This study has shown how (a) detailed multi-disciplinary analyses of a single variant can reclassify rare missense variants in FH and (b) careful pathological review of renal cancers is obligatory when HLRCC is suspected.


Assuntos
Fumarato Hidratase , Leiomiomatose , Mutação de Sentido Incorreto , Síndromes Neoplásicas Hereditárias , Neoplasias Cutâneas , Neoplasias Uterinas , Humanos , Fumarato Hidratase/genética , Leiomiomatose/genética , Leiomiomatose/patologia , Feminino , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Neoplasias Uterinas/genética , Neoplasias Uterinas/patologia , Síndromes Neoplásicas Hereditárias/genética , Síndromes Neoplásicas Hereditárias/patologia , Neoplasias Renais/genética , Neoplasias Renais/patologia , Linhagem , Mutação em Linhagem Germinativa , Masculino , Adulto , Predisposição Genética para Doença , Pessoa de Meia-Idade
2.
Int J Mol Sci ; 25(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38397005

RESUMO

Gamma-aminobutyric acid (GABA)-producing lactic acid bacteria (LAB) can be used as starters in the development of GABA-enriched functional fermented foods. In this work, four GABA-producing strains each of Lactococcus lactis and Streptococcus thermophilus species were isolated from cow's milk, and their phenotypic, technological, and safety profiles determined. Genome analysis provided genetic support for the majority of the analyzed traits, namely, GABA production, growth in milk, and the absence of genes of concern. The operon harboring the glutamate decarboxylase gene (gadB) was chromosomally encoded in all strains and showed the same gene content and gene order as those reported, respectively, for L. lactis and S. thermophilus. In the latter species, the operon was flanked (as in most strains of this species) by complete or truncated copies of insertion sequences (IS), suggesting recent acquisition through horizontal gene transfer. The genomes of three L. lactis and two S. thermophilus strains showed a gene encoding a caseinolytic proteinase (PrtP in L. lactis and PrtS in S. thermophilus). Of these, all but one grew in milk, forming a coagulum of good appearance and an appealing acidic flavor and taste. They also produced GABA in milk supplemented with monosodium glutamate. Two L. lactis strains were identified as belonging to the biovar. diacetylactis, utilized citrate from milk, and produced significant amounts of acetoin. None of the strains showed any noticeable antibiotic resistance, nor did their genomes harbor transferable antibiotic resistance genes or genes involved in toxicity, virulence, or pathogenicity. Altogether these results suggest that all eight strains may be considered candidates for use as starters or components of mixed LAB cultures for the manufacture of GABA-enriched fermented dairy products.


Assuntos
Queijo , Lactobacillales , Lactococcus lactis , Animais , Leite/microbiologia , Lactococcus lactis/genética , Streptococcus thermophilus/genética , Ácido gama-Aminobutírico , Genômica , Fermentação , Queijo/microbiologia
3.
Environ Sci Technol ; 57(24): 8863-8869, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37279259

RESUMO

Ocean alkalinity enhancement (OAE) is being considered as a way of achieving large-scale removals of carbon dioxide from the atmosphere. Research on the risks and benefits of different OAE approaches is expanding apace, but it remains difficult to anticipate and appraise the potential impacts to human communities that OAE might generate. These impacts, however, will be critical to evaluating the viability of specific OAE projects. This paper draws on the authors' involvement in interdisciplinary assessment of OAE (1) to identify the factors that currently limit characterization of potential social impacts and (2) to propose ways of reconfiguring OAE research to better consider these.


Assuntos
Atmosfera , Mudança Social , Humanos , Dióxido de Carbono/análise , Oceanos e Mares
4.
Molecules ; 27(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36500440

RESUMO

The rare-earth-free MnAlC alloy is currently considered a very promising candidate for permanent magnet applications due to its high anisotropy field and relatively high saturation magnetization and Curie temperature, besides being a low-cost material. In this work, we presented a simple fabrication route that allows for obtaining a magnetically enhanced bulk τ-MnAlC magnet. In the fabrication process, an electric arc-melting method was carried out to melt ingots of MnAlC alloys. A two-step solution treatment at 1200 °C and 1100 °C allowed us to synthesize a pure room-temperature ε-MnAlC ingot that completely transformed into τ-MnAlC alloy, free of secondary phases, after an annealing treatment at 550 °C for 30 min. The Rietveld refinements and magnetization measurements demonstrated that the quenched process produces a phase-segregated ε-MnAlC alloy that is formed by two types of ε-phases due to local fluctuation of the Mn. Room-temperature hysteresis loops showed that our improved τ-MnAlC alloy exhibited a remanent magnetization of 42 Am2/kg, a coercive field of 0.2 T and a maximum energy product, (BH)max, of 6.07 kJ/m3, which is higher than those reported in previous works using a similar preparation route. Experimental evidence demonstrated that the synthesis of a pure room-temperature ε-MnAlC played an important role in the suppression of undesirable phases that deteriorate the permanent magnet properties of the τ-MnAlC. Finally, magnetic images recorded by Lorentz microscopy allowed us to observe the microstructure and magnetic domain walls of the optimized τ-MnAlC. The presence of magnetic contrasts in all the observed grains allowed us to confirm the high-quality ferromagnetic behavior of the system.


Assuntos
Imãs , Metais Terras Raras , Imãs/química , Ligas/química , Temperatura , Magnetismo
5.
Rev Argent Microbiol ; 54(2): 152-157, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34246508

RESUMO

Quality evaluation of commercial inoculants is essential to warrant an adequate crop response to inoculation within a biosecurity framework. In this sense, this work is aimed at standardizing and validating the drop plate method for the enumeration of Azospirillum viable cells as an alternative to the spread plate technique, which is currently proposed in the consensus protocol of the REDCAI network. Between 14 and 25 private and public laboratories participated in three independent trials. We obtained consistent and robust results that allowed to confirm that both techniques are equivalent, concluding that the drop plate method is an alternative enumeration technique that is adequate to be included in the abovementioned consensus protocol.


Assuntos
Azospirillum , Azospirillum/fisiologia , Consenso
6.
Molecules ; 26(7)2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33917637

RESUMO

The majority of snacks expanded by extrusion (SEE) are made with vegetable sources, to improve their nutritional content; it has been proposed to incorporate squid (Dosidicus gigas), due to its high protein content, low price and high availability. However, the interaction of proteins of animal origin with starch during extrusion causes negative effects on the sensory properties of SEE, so it is necessary to know the type of protein-carbohydrate interactions and their effect on these properties. The objective of this research was to study the interaction of proteins and carbohydrates of SEE elaborated with squid mantle, potato and corn. The nutritional composition and protein digestibility were evaluated, Fourier transform infrared (FTIR) and Differential Scanning Calorimetry (DSC) were used to study the formation of protein-starch complexes and the possible regions responsible for their interactions. The SEE had a high protein content (40-85%) and biological value (>93%). The melting temperature (Tm) was found between 145 and 225 °C; the Tm values in extruded samples are directly proportional to the squid content. The extrusion process reduced the amine groups I and II responsible for the protein-protein interaction and increased the O-glucosidic bonds, so these bonds could be responsible for the protein-carbohydrate interactions.


Assuntos
Varredura Diferencial de Calorimetria , Decapodiformes/química , Proteínas/química , Lanches , Solanum tuberosum/química , Amido/química , Animais , Espectroscopia de Infravermelho com Transformada de Fourier
7.
J Sci Food Agric ; 101(11): 4829-4837, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33502792

RESUMO

BACKGROUND: Virgin olive oil (VOO) is greatly appreciated for its organoleptic features, which can be ascribed mainly to the presence of very chemically diverse volatile components. It is well known that the VOO volatile fraction depends strongly on different aspects, which encompass genetic, agronomic, processing, and post-processing factors. In this research, we developed a method for the qualitative and semiquantitative determination of volatile components in VOOs subjected to thermal stress by headspace extraction online coupled to gas chromatography-mass spectrometry (HS-GC-MS). RESULTS: The method was applied to 100 extra-virgin olive oil (EVOO) samples, which led to the tentative identification of 52 volatile components, including 12 alcohols, 17 aldehydes, three ketones, one ether, two furans, two carboxylic acids, and 15 hydrocarbons. The method was used to study the cultivar effect and the main biochemical pathways involved in the synthesis of volatile compounds, with special emphasis on those formed by degradation of unsaturated fatty acids (FAs). Principal component analysis (PCA), explaining 76.7% of the total variability, showed that the volatile profile of EVOOs subjected to thermal stress allowed discriminating samples from different cultivars. CONCLUSION: Volatiles detected in EVOOs subjected to thermal stress with the highest contribution to discrimination between the selected cultivars were correlated with the concentration of the three main FAs in VOO, namely oleic, linoleic, and linolenic acids. The FA profile seems to be especially relevant to explain the concentration of certain volatile compounds with direct incidence on the organoleptic properties. © 2021 Society of Chemical Industry.


Assuntos
Ácidos Graxos/química , Azeite de Oliva/química , Compostos Orgânicos Voláteis/química , Álcoois/química , Aldeídos/química , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Cetonas/química , Olea/química
8.
Plant Foods Hum Nutr ; 75(1): 76-82, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31848854

RESUMO

ADP-glucose pyrophosphorylase (AGPase) is a key enzyme of starch synthesis in seeds, tubers and fruits. UDP-glucose pyrophosphorylase (UGPase) is an important enzyme of sucrose metabolism in the cytosol while alkaline phosphatase (ALP) is a marker enzyme of the amyloplast that keeps the production of ADPG by removing PPi. Unripe banana accumulates starch in the pulp during development, while ripe fruits are characterized by the accumulation of soluble sugars. The aim of the study was to compare starch granule structure, carbohydrate levels, subcellular location and activities of three enzymes: AGPase, UGPase and ALP. Protein extracts from the cytosolic and amyloplastidial fractions were obtained from the pulp of banana fruit at three developmental stages (11, 16 and 21 weeks after flowering) and analyzed by electrophoresis and immunodetection. Protein profiles were similar during ripening, showing a main electrophoretic band at 50-55 kDa. Higher protein content was found in the cytosolic than in the amyloplastidial fraction. Starch granules and ALP activity were enriched in the amyloplast, whereas AGPase showed a subcellular distribution similar to UGPase. Immunoblot analysis also confirmed the presence of AGPase in both cytosol and amyloplast. AGPase activity was higher in the cytosol than in the amyloplast. Both AGPase activity and western blot band intensity were highest at 16 weeks. UGPase activity was highest at 21 weeks. We conclude that cytosolic production of ADP-glucose is not an exclusive feature of cereal endosperms due to plant breeding, but it also occurs in fruits of non-domesticated plants such as tropical banana (Musa acuminata). This work increases our understanding about pyrophosphorylase activities in the pulp of banana fruit.


Assuntos
Musa , Citosol , Frutas , Glucose-1-Fosfato Adenililtransferase , Plastídeos , Amido
9.
Pestic Biochem Physiol ; 155: 1-7, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30857618

RESUMO

Continuous use of glyphosate in citrus groves in the Gulf of Mexico region has selected for resistant Parthenium hysterophorus L. populations. In this study, the target-site and non-target-site resistance mechanisms were characterized in three putative glyphosate-resistant (GR) P. hysterophorus populations, collected in citrus groves from Acateno, Puebla (GR1 and GR2) and Martínez de la Torre, Veracruz (GR3), and compared with a susceptible population (GS). Based on plant mortality, the GR populations were 9.2-17.3 times more resistant to glyphosate than the GS population. The low shikimate accumulation in the GR population confirmed this resistance. Based on plant mortality and shikimate accumulation, the GR3 population showed intermediate resistance to glyphosate. The GR populations absorbed 15-28% less 14C-glyphosate than the GS population (78.7% absorbed from the applied) and retained 48.7-70.7% of 14C-glyphosate in the treated leaf, while the GS population translocated ~68% of absorbed herbicide to shoots and roots. The GR3 population showed the lowest translocation and absorption rates, but was found to be susceptible at the target site level. The 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene sequence of the GR1 and GR2 populations showed the Pro106-Ser mutation, conferring 19- and 25-times more resistance in comparison to the GS population, respectively. Reduced absorption and impaired translocation conferred glyphosate resistance on the GR3 population, and contributed partially to the resistance of the GR1 and GR2 populations. Additionally, the Pro-106-Ser mutation increased the glyphosate resistance of the last two P. hysterophorus populations.


Assuntos
Glicina/análogos & derivados , Herbicidas/farmacologia , Tanacetum parthenium/efeitos dos fármacos , Tanacetum parthenium/metabolismo , 3-Fosfoshikimato 1-Carboxiviniltransferase , Glicina/farmacologia , Resistência a Herbicidas , Mutação/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Glifosato
10.
Proc Natl Acad Sci U S A ; 112(19): 5979-84, 2015 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-25918372

RESUMO

Environmental governance is more effective when the scales of ecological processes are well matched with the human institutions charged with managing human-environment interactions. The social-ecological systems (SESs) framework provides guidance on how to assess the social and ecological dimensions that contribute to sustainable resource use and management, but rarely if ever has been operationalized for multiple localities in a spatially explicit, quantitative manner. Here, we use the case of small-scale fisheries in Baja California Sur, Mexico, to identify distinct SES regions and test key aspects of coupled SESs theory. Regions that exhibit greater potential for social-ecological sustainability in one dimension do not necessarily exhibit it in others, highlighting the importance of integrative, coupled system analyses when implementing spatial planning and other ecosystem-based strategies.


Assuntos
Conservação dos Recursos Naturais , Animais , Países em Desenvolvimento , Ecologia , Ecossistema , Pesqueiros , Peixes , Abastecimento de Alimentos , Geografia , Humanos , México , Meio Social , Análise de Sistemas
11.
Sensors (Basel) ; 18(3)2018 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-29558432

RESUMO

Timing points used in running races and other competition events are generally based on radio-frequency identification (RFID) technology. Athletes' times are calculated via passive RFID tags and reader kits. Specifically, the reader infrastructure needed is complex and requires the deployment of a mat or ramps which hide the receiver antennae under them. Moreover, with the employed tags, it is not possible to transmit additional and dynamic information such as pulse or oximetry monitoring, alarms, etc. In this paper we present a system based on two low complex schemes allowed in Bluetooth Low Energy (BLE): the non-connectable undirected advertisement process and a modified version of scannable undirected advertisement process using the new capabilities present in Bluetooth 5. After fully describing the system architecture, which allows full real-time position monitoring of the runners using mobile phones on the organizer side and BLE sensors on the participants' side, we derive the mobility patterns of runners and capacity requirements, which are determinant for evaluating the performance of the proposed system. They have been obtained from the analysis of the real data measured in the last Barcelona Marathon. By means of simulations, we demonstrate that, even under disadvantageous conditions (50% error ratio), both schemes perform reliably and are able to detect the 100% of the participants in all the cases. The cell coverage of the system needs to be adjusted when non-connectable process is considered. Nevertheless, through simulation and experimental, we show that the proposed scheme based on the new events available in Bluetooth 5 is clearly the best implementation alternative for all the cases, no matter the coverage area and the runner speed. The proposal widely exceeds the detection requirements of the real scenario, surpassing the measured peaks of 20 sensors per second incoming in the coverage area, moving at speeds that range from 1.5 m/s to 6.25 m/s. The designed real test-bed shows that the scheme is able to detect 72 sensors below 600 ms, fulfilling comfortably the requirements determined for the intended application. The main disadvantage of this system would be that the sensors are active, but we have proved that its consumption can be so low (9.5 µA) that, with a typical button cell, the sensor battery life would be over 10,000 h of use.

12.
Plant Foods Hum Nutr ; 73(4): 308-313, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30238426

RESUMO

Red arils of Pithecellobium dulce fruit, commonly known as guamuchil, show high antioxidant (AOx) and α-glucosidase inhibitory (IαG) activities, which have been mainly associated with the content of unknown anthocyanins. In this study, the AOx (i.e., DPPH and ABTS as Trolox equivalents, µmol TE/g) and IαG (as half-maximal inhibitory concentration, IC50, mg/mL) activities of the anthocyanin-rich fraction (ARF) obtained from red arils were contrasted with those of the methanol extract (ME), and the main ARF anthocyanins were characterized by HPLC-DAD-ESI-MS, GC-MS and 1H-NMR. The AOx and IαG values of the ARF (DPPH = 597.8; ABTS = 884.01; IαG = 0.06) were better than those of the ME (DPPH = 41.5; ABTS = 142.3; IαG = 17.5); remarkably, the ARF IαG value was about 42 times lower than that of acarbose. The main anthocyanins in ARF were pelargonidin 3-O-glucoside and cyanidin 3-O-glucoside. Thus, the consumption of red P. dulce arils could provide health benefits for prevention/treatment of chronic degenerative diseases such as diabetes.


Assuntos
Antocianinas/análise , Antocianinas/farmacologia , Antioxidantes/farmacologia , Fabaceae/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Antocianinas/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Glucosídeos/análise , Glucosídeos/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
13.
Plant Foods Hum Nutr ; 73(2): 122-129, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29516285

RESUMO

Chickpea (Cicer arietinum L.) genotypes, nine kabuli from Mexico and 9 desi from other countries, were investigated for their phenolic profiles and antioxidant activity (AA). Phenolics in methanol extracts (ME) were analyzed by ultra-performance liquid chromatography coupled to diode array detection and mass spectrometry (UPLC-DAD-MS), whereas the AA was measured as Trolox equivalents (TE) by ABTS, DPPH and FRAP methods. Twenty phenolic compounds were identified in the ME and their levels showed a great variability among the chickpea genotypes. Phenolic acids and flavonoids were the most abundant compounds in kabuli and desi genotypes, respectively. The AA values (µmol TE/ 100 g dw) by ABTS (278-2417), DPPH (52-1650), and FRAP (41-1181) were mainly associated with the content of sinapic acid hexoside, gallic acid, myricetin, quercetin, catechin, and isorhamnetin, suggesting they are the main compounds responsible for the AA. The sum of the AA obtained for standards of these compounds evaluated at the concentration found in the extracts accounted for 34.3, 69.8, and 47.0% of the AA in the extract by ABTS, DPPH, and FRAP, respectively. In the AA by DPPH, most of the mixtures of these compounds resulted in synergistic interactions. Three desi genotypes with black seeds (ICC 4418, ICC 6306, and ICC 3761) showed the highest AA and flavonoids content, whereas the most promising kabuli genotypes were Surutato 77, Bco. Sin. 92, and Blanoro that showed the highest values of phenolic acids. These genotypes represent good sources of antioxidants for the improvement of nutraceutical properties in chickpea.


Assuntos
Antioxidantes/análise , Cicer/química , Flavonoides/análise , Hidroxibenzoatos/análise , Catequina/análise , Cromanos/análise , Cromatografia Líquida , Ácido Gálico/análise , Genótipo , Espectrometria de Massas , Quercetina/análogos & derivados , Quercetina/análise , Sementes/química
14.
Emerg Infect Dis ; 23(5): 872-874, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28418305

RESUMO

An investigation in Panama found that Punta Toro virus species complex (PTVs) may contribute to febrile illnesses with symptoms mirroring those of dengue fever. However, further studies are needed to determine if PTV infection causes only a mild disease or if it can have more serious manifestations in some patients.


Assuntos
Infecções por Bunyaviridae/diagnóstico , Infecções por Bunyaviridae/virologia , Fenótipo , Phlebovirus , Infecções por Bunyaviridae/epidemiologia , Infecções por Bunyaviridae/história , Estudos de Casos e Controles , História do Século XXI , Humanos , Panamá/epidemiologia , Phlebovirus/classificação , Phlebovirus/genética , Filogenia , Filogeografia , RNA Viral , Análise de Sequência de DNA
15.
Sensors (Basel) ; 17(9)2017 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-28867786

RESUMO

The device discovery process is one of the most crucial aspects in real deployments of sensor networks. Recently, several works have analyzed the topic of Bluetooth Low Energy (BLE) device discovery through analytical or simulation models limited to version 4.x. Non-connectable and non-scannable undirected advertising has been shown to be a reliable alternative for discovering a high number of devices in a relatively short time period. However, new features of Bluetooth 5.0 allow us to define a variant on the device discovery process, based on BLE scannable undirected advertising events, which results in higher discovering capacities and also lower power consumption. In order to characterize this new device discovery process, we experimentally model the real device behavior of BLE scannable undirected advertising events. Non-detection packet probability, discovery probability, and discovery latency for a varying number of devices and parameters are compared by simulations and experimental measurements. We demonstrate that our proposal outperforms previous works, diminishing the discovery time and increasing the potential user device density. A mathematical model is also developed in order to easily obtain a measure of the potential capacity in high density scenarios.

16.
Sensors (Basel) ; 17(3)2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28273801

RESUMO

The purpose of this paper is to evaluate from a real perspective the performance of Bluetooth Low Energy (BLE) as a technology that enables fast and reliable discovery of a large number of users/devices in a short period of time. The BLE standard specifies a wide range of configurable parameter values that determine the discovery process and need to be set according to the particular application requirements. Many previous works have been addressed to investigate the discovery process through analytical and simulation models, according to the ideal specification of the standard. However, measurements show that additional scanning gaps appear in the scanning process, which reduce the discovery capabilities. These gaps have been identified in all of the analyzed devices and respond to both regular patterns and variable events associated with the decoding process. We have demonstrated that these non-idealities, which are not taken into account in other studies, have a severe impact on the discovery process performance. Extensive performance evaluation for a varying number of devices and feasible parameter combinations has been done by comparing simulations and experimental measurements. This work also includes a simple mathematical model that closely matches both the standard implementation and the different chipset peculiarities for any possible parameter value specified in the standard and for any number of simultaneous advertising devices under scanner coverage.

17.
Pharm Biol ; 55(1): 1473-1482, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28347185

RESUMO

CONTEXT: Helicteres vegae Cristóbal (Sterculiaceae) (Hv) and Heliopsis sinaloensis B.L. Turner (Asteraceae) (Hs) are endangered and poorly studied plant species; related plants have been used against chronic-degenerative and infectious diseases. Therefore, Hv and Hs could be sources of bioactive compounds against these illnesses. OBJECTIVE: To determine the chemical composition and biological activities (antioxidant, antimutagenic and antimicrobial) of Hv and Hs leaves (L) and stems (S). MATERIALS AND METHODS: Methanol extracts (ME) of each plant/tissue were evaluated for their phytochemicals; phenolics (HPLC-DAD-ESI-MS); antioxidant activity (AA) (0.125-4 mg/mL) (DPPH, ABTS, ORAC and ß-carotene discoloration); antimutagenicity (0.5 and 1 mg/plate) (Ames assay, tester strain Salmonella enterica serovar Typhimurium YG1024, 1-nitropyrene as mutagen); activity against human pathogens (1 mg/mL); and toxicity (0.01-2 mg/mL) (Artemia salina assay). RESULTS: All ME showed flavonoids and triterpenes/steroids. The ME-SHv had the highest content of total phenolics (TP) (2245.82 ± 21.45 mg GAE/100 g d.w.) and condensed tannins (603.71 ± 1.115 mg CE/100 g d.w.). The compounds identified were flavonoids (kaempferol 7-O-coumaroylhexoside, and two kaempferol 7-O-rhamnosylhexosides) and phenolics [rosmarinic acid, and 3'-O-(8″-Z-caffeoyl) rosmarinic acid]. The ME-LHs showed the highest content of flavonoids (357.88 mg RE/g d.w.) and phenolic acids (238.58 mg CAE/g d.w.) by HPLC. The ME-SHv showed the highest AA. All ME were strong antimutagens (63.3-85.7%). Only the Hs extracts were toxic (ME-LHs, LC50 = 94.9 ± 1.7 µg/mL; ME-SHs, LC50 = 89.03 ± 4.42 µg/mL). DISCUSSION AND CONCLUSIONS: Both Hv and Hs are potential sources of preventive and therapeutic agents against chronic-degenerative diseases.


Assuntos
Anti-Infecciosos/farmacologia , Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Asteraceae/química , Malvaceae/química , Extratos Vegetais/farmacologia , Animais , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/toxicidade , Antimutagênicos/química , Antimutagênicos/isolamento & purificação , Antimutagênicos/toxicidade , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/toxicidade , Artemia/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Benzotiazóis/química , Compostos de Bifenilo/química , Cromatografia Líquida de Alta Pressão , Giardia lamblia/efeitos dos fármacos , Giardia lamblia/crescimento & desenvolvimento , Metanol/química , Testes de Sensibilidade Microbiana , Testes de Mutagenicidade , Capacidade de Absorbância de Radicais de Oxigênio , Testes de Sensibilidade Parasitária , Fitoterapia , Picratos/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Folhas de Planta/química , Caules de Planta/química , Plantas Medicinais , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Solventes/química , Espectrometria de Massas por Ionização por Electrospray , Ácidos Sulfônicos/química , beta Caroteno/química
18.
J Cell Sci ; 127(Pt 15): 3382-95, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24895402

RESUMO

In neurons, secretory organelles within the cell body are complemented by the dendritic endoplasmic reticulum (ER) and Golgi outposts (GOPs), whose role in neurotransmitter receptor trafficking is poorly understood. γ-aminobutyric acid (GABA) type B metabotropic receptors (GABABRs) regulate the efficacy of synaptic transmission throughout the brain. Their plasma membrane availability is controlled by mechanisms involving an ER retention motif and assembly-dependent ER export. Thus, they constitute an ideal molecular model to study ER trafficking, but the extent to which the dendritic ER participates in GABABR biosynthesis has not been thoroughly explored. Here, we show that GABAB1 localizes preferentially to the ER in dendrites and moves long distances within this compartment. Not only diffusion but also microtubule and dynein-dependent mechanisms control dendritic ER transport. GABABRs insert throughout the somatodendritic plasma membrane but dendritic post-ER carriers containing GABABRs do not fuse selectively with GOPs. This study furthers our understanding of the spatial selectivity of neurotransmitter receptors for dendritic organelles.


Assuntos
Dendritos/metabolismo , Dendritos/ultraestrutura , Retículo Endoplasmático/metabolismo , Neurônios GABAérgicos/metabolismo , Giro Para-Hipocampal/fisiologia , Receptores de GABA-B/metabolismo , Transmissão Sináptica , Animais , Células Cultivadas , Difusão , Dineínas/metabolismo , Feminino , Neurônios GABAérgicos/ultraestrutura , Camundongos , Camundongos Transgênicos , Microtúbulos/metabolismo , Transporte Proteico , Ratos , Ratos Sprague-Dawley , Receptores de GABA-B/genética , Imagem com Lapso de Tempo
19.
Plant Foods Hum Nutr ; 71(2): 218-24, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27170034

RESUMO

The snack foods market is currently demanding healthier products. A ready-to-eat expanded snack with high nutritional and antioxidant value was developed from a mixture (70:30) of whole amarantin transgenic maize (Zea mays L.) and black common bean (Phaseolus vulgaris L.) by optimizing the extrusion process. Extruder operation conditions were: feed moisture content (FMC, 15-25 %, wet basis), barrel temperature (BT, 120-170 °C), and screw speed (SS, 50-240). The desirability numeric method of the response surface methodology (RSM) was applied as the optimization technique over four response variables [expansion ratio (ER), bulk density (BD), hardness (H), antioxidant activity (AoxA)] to obtain maximum ER and AoxA, and minimum BD, and H values. The best combination of extrusion process variables for producing an optimized expanded snack (OES, healthy snack) were: FMC = 15 %/BT = 157 °C/SS = 238 rpm. The OES had ER = 2.86, BD = 0.119 g/cm (3) , H = 1.818 N, and AoxA = 13,681 µmol Trolox equivalent (TE)/100 g, dry weight. The extrusion conditions used to produce the OES increased the AoxA (ORAC: +18 %, ABTS:+20 %) respect to the unprocessed whole grains mixture. A 50 g portion of OES had higher protein content (7.23 vs 2.32 g), total dietary fiber (7.50 vs 1.97 g), total phenolic content (122 vs 47 mg GAE), and AoxA (6626 vs 763 µmol TE), and lower energy (169 vs 264 kcal) than an expanded commercial snack (ECS = Cheetos™). Because of its high content of quality protein, dietary fiber and phenolics, as well as high AoxA and low energy density, the OES could be used for health promotion and chronic disease prevention and as an alternative to the widely available commercial snacks with high caloric content and low nutritional/nutraceutical value.


Assuntos
Amaranthus/genética , Antioxidantes/metabolismo , Phaseolus/química , Fenóis/metabolismo , Lanches , Zea mays/química , Amaranthus/química , Antioxidantes/análise , Fibras na Dieta/análise , Fibras na Dieta/metabolismo , Proteínas Alimentares/análise , Proteínas Alimentares/metabolismo , Farinha/análise , Manipulação de Alimentos , Valor Nutritivo , Phaseolus/genética , Fenóis/análise , Proteínas de Plantas/análise , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Sementes/química , Sementes/genética , Temperatura , Grãos Integrais , Zea mays/genética
20.
J Insect Sci ; 152015.
Artigo em Inglês | MEDLINE | ID: mdl-25797796

RESUMO

The Mexican fruit fly, Anastrepha ludens Loew (Diptera: Tephritidae), is one of the most harmful pests of mango causing direct damage by oviposition on the fruit pulp. Mango for export is subjected to hydrothermal treatment as a quarantine method for the control of this pest, but exposure to heat for long periods of time reduces considerably the quality and shelf-life of treated fruit. The aim of this work was to study morphological changes of third-instar larvae and adults of A. ludens after in vitro exposure to high temperature at sublethal times. A heating block system was used to expose larvae at 46.1°C for 19.6 and 12.9 min, producing 94.6 and 70% mortality, respectively. Treated larvae were processed for optical microscopy. A fraction of surviving treated larvae was separated into containers with artificial diet to allow development into adults. Adult sexual organs were dissected and processed for transmission electron microscopy analysis. Results showed that 94.6% of the treated larvae died at 46.1°C for 19.6 min and none of the surviving larvae eclosed to adulthood, as they developed as malformed puparia. For the in vitro treatment at 46.1°C during 12.9 min, 70% of the treated larvae died and only 3.75% reached the adult stage, but ultrastructural damage in the male testes and in the female ovaries was observed. Additionally, 11.1% of the adult flies from the in vitro treatment also showed wing malformation and were incapable of flying. The analysis showed that surviving flies were unable to reproduce.


Assuntos
Controle de Insetos/métodos , Tephritidae/fisiologia , Animais , Feminino , Temperatura Alta , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Mangifera , Tephritidae/crescimento & desenvolvimento
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