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2.
Int J Biol Macromol ; 202: 453-467, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35031317

RESUMO

Electrohydrodynamic processing (EHDP) allows the use of a wide range of biopolymers and solvents, including food-grade biopolymers and green solvents, for the development of micro- and nanostructures. These structures present a high surface-area-to-volume ratio and different shapes and morphologies. The aim of this work was to design and produce hydroxypropyl methylcellulose (HPMC)-based micro- and nanostructures through EHD processing using green solvents, while exploring the influence of process and solution parameters, and incorporating a bioactive extracted from a food by-product. Low (LMW) and high (HMW) molecular weight HPMC have been used as polymers. The design-of-experiments methodology was used to determine the effects of process parameters (polymer concentration, flow rate, tip-to-collector distance, and voltage) of EHDP on the particle and fibre diameter, aspect ratio, diameter distribution, aspect ratio distribution, and percentage of fibre breakage. Additionally, melanoidins extracted from spent coffee grounds were encapsulated into the HPCM-based structures at a concentration of 2.5 mg melanoidins/mL of the polymer solution. Polymer solutions were characterised regarding their viscosity, surface tension and conductivity, and showed that the incorporation of melanoidins increased the viscosity and conductivity values of the polymer solutions. The developed structures were characterised regarding their thermal properties, crystallinity and morphology before and after melanoidin incorporation and it was observed that melanoidin incorporation did not significantly influence the characteristics of the produced micro- and nanostructures. Based on the results, it is possible to envision the use of the produced micro- and nanostructures in a wide range of applications, both in food and biomedical fields.


Assuntos
Nanoestruturas , Polímeros , Condutividade Elétrica , Derivados da Hipromelose , Polímeros/química
3.
Psychol Addict Behav ; 35(6): 749-759, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33764086

RESUMO

OBJECTIVE: Conflicting evidence exists regarding the effects of cannabis on alcohol consumption, with some studies suggesting that cannabis is a substitute for alcohol, whereas others suggest that cannabis complements alcohol, thereby increasing drinking. Cannabidiol (CBD) has shown preclinical promise in decreasing alcohol consumption. This study explores the effects of cannabis containing different potencies of CBD and delta-9-tetrahydrocannabinol (THC) on alcohol consumption. METHOD: In this naturalistic observational study, 120 cannabis and alcohol-using adults (mean age = 33.2 years, 39.2% female, 83.3% white) were assigned to use one of three legal-market cannabis strains (predominantly THC, predominantly CBD, and CBD + THC) ad libitum for 5 days. Timeline Followback data on drinking and cannabis use were collected at a baseline session pertaining to the 30 days prior to the ad libitum period, and data regarding alcohol and cannabis use during the 5-day period were collected at follow-up (FU), immediately following the 5-day period. RESULTS: Regression models tested strain differences in drinking outcomes during the ad libitum period. Orthogonal contrast codes were created comparing the CBD group with the other two groups and comparing the THC group with the CBD + THC group. The CBD group drank fewer drinks per drinking day (p < .05), had fewer alcohol use days (p < .05), and fewer alcohol and cannabis co-use days (p < .05) compared with the other groups. No differences emerged between the THC and the CBD + THC group. CONCLUSIONS: Cannabinoid content should be considered in studies of alcohol and cannabis co-use. Findings are consistent with preclinical work, suggesting that CBD may be associated with decreased alcohol consumption. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Canabidiol , Canabinoides , Cannabis , Adulto , Dronabinol , Etanol , Humanos
4.
Food Res Int ; 125: 108586, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554037

RESUMO

There is an increasing demand for alternative and sustainable protein sources, such as vegetables, insects and microorganisms, that can meet the nutritional and sensory pleasantness needs of consumers. This emergent interest for novel protein sources, allied with "green" and cost-effective processing technologies, such as high hydrostatic pressure, ohmic heating and pulsed electric fields, can be used as strategies to improve the consumption of proteins from sustainable sources without compromising food security. In addition to their nutritional value, these novel proteins present several technological-functional properties that can be used to create various protein systems in different scales (i.e., macro, micro and nano scale), which can be tailored for a specific application in innovative food products. However, in order for these novel protein sources to be broadly used in future food products, their fate in the human gastrointestinal tract (e.g., digestion and bioavailability) must be assessed, as well as their safety for consumers must be clearly demonstrated. In particular, these proteins may become novel allergens triggering adverse reactions and, therefore, a comprehensive allergenicity risk assessment is needed. This review presents an overview of the most promising alternative protein sources, their application in the production of innovative food systems, as well as their potential effects on human health. In addition, new insights on sustainable processing strategies are given.


Assuntos
Proteínas Alimentares , Proteínas de Bactérias , Qualidade de Produtos para o Consumidor , Manipulação de Alimentos , Hipersensibilidade Alimentar , Inocuidade dos Alimentos , Tecnologia de Alimentos , Proteínas Fúngicas , Proteínas de Insetos , Valor Nutritivo , Proteínas de Vegetais Comestíveis , Medição de Risco
5.
J Evol Biol ; 29(11): 2205-2218, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27500505

RESUMO

Each of the four serotypes of mosquito-borne dengue virus (DENV-1-4) comprises multiple, genetically distinct strains. Competitive displacement between strains within a serotype is a common feature of DENV epidemiology and can trigger outbreaks of dengue disease. We investigated the mechanisms underlying two sequential displacements by DENV-3 strains in Sri Lanka that each coincided with abrupt increases in dengue haemorrhagic fever (DHF) incidence. First, the post-DHF strain displaced the pre-DHF strain in the 1980s. We have previously shown that post-DHF is more infectious than pre-DHF for the major DENV vector, Aedes aegypti. Then, the ultra-DHF strain evolved in situ from post-DHF and displaced its ancestor in the 2000s. We predicted that ultra-DHF would be more infectious for Ae. aegypti than post-DHF but found that ultra-DHF infected a significantly lower percentage of mosquitoes than post-DHF. We therefore hypothesized that ultra-DHF had effected displacement by disseminating in Ae. aegypti more rapidly than post-DHF, but this was not borne out by a time course of mosquito infection. To elucidate the mechanisms that shape these virus-vector interactions, we tested the impact of RNA interference (RNAi), the principal mosquito defence against DENV, on replication of each of the three DENV strains. Replication of all strains was similar in mosquito cells with dysfunctional RNAi, but in cells with functional RNAi, replication of pre-DHF was significantly suppressed relative to the other two strains. Thus, differences in susceptibility to RNAi may account for the differences in mosquito infectivity between pre-DHF and post-DHF, but other mechanisms underlie the difference between post-DHF and ultra-DHF.


Assuntos
Vírus da Dengue/patogenicidade , Dengue/epidemiologia , Aedes , Animais , Vírus da Dengue/genética , Interferência de RNA , Sri Lanka , Virulência
6.
Braz J Biol ; 66(1A): 143-50, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16680317

RESUMO

Six reproductive classes of male Oligosarcus hepsetus (Cuvier, 1829), a medium-sized carnivorous Characiform species, are described based on macroscopic and histological techniques. A total of 175 individuals were caught monthly between April 2001 and June 2002 in the Lajes Reservoir, Brazil, one of the largest impoundment areas in the state of Rio de Janeiro. The reproductive classes were based upon changes in the testicular morphology and stages of germinative cells, i.e., resting, early maturing, late maturing, mature, partially spent and totally spent. Fish in the resting class showed testes with spermatogonia and spermatocytes along the wall of seminal lobules, while spermatids were present in the lumina of the lobules. During early maturing, active spermatogenesis occurs throughout the testis; in the late maturing and mature classes, the lobules are swollen with sperm that are typical of fish in breeding condition. Spent testes presented seminal lobules with residual spermatozoa, coinciding with decreasing GSI and greatly reduced sperm production. Overall, the testicular morphology and class of maturity development of O. hepsetus in the Lajes reservoir did not differ significantly from those of closely related species in other lentic environments. Lower GSI values in the oligotrophic Lajes reservoir than in other eutrophic natural lakes suggest that this species may be modifying this aspect of its reproductive strategy in response to the artificial environment.


Assuntos
Peixes/crescimento & desenvolvimento , Maturidade Sexual/fisiologia , Espermatogênese/fisiologia , Espermatozoides/crescimento & desenvolvimento , Testículo/crescimento & desenvolvimento , Animais , Masculino , Espermatozoides/citologia
7.
Braz. j. biol ; 66(1a): 143-150, Feb. 2006. ilus, graf
Artigo em Inglês | LILACS | ID: lil-426276

RESUMO

Seis classes de maturação dos testículos de Oligosarcus hepsetus (Cuvier, 1829), um Characiforme carnívoro de médio porte, foram descritas com base em técnicas macro e microscópicas. Um total de 175 indivíduos foi capturado mensalmente entre abril/2001 e junho/2002 no Reservatório de Lajes, Brasil, uma das maiores áreas represadas do Estado do Rio de Janeiro. As classes reprodutivas foram estabelecidas de acordo com mudanças na morfologia dos testículos e nos estádios das células germinativas: repouso, maturação inicial, maturação final, maduro, parcialmente esvaziado e totalmente esvaziado. Os testículos da classe em repouso apresentaram espermatogônias e espermatócitos ao longo da parede dos túbulos seminíferos, enquanto as espermátides foram encontradas no lúmen dos túbulos. Nos testículos em maturação inicial, a espermatogênese é intensa; em maturação avançada e maduros, os túbulos estão repletos de sêmen, que são característicos de peixes aptos a reprodução. Testículos esvaziados apresentaram sêmen residual nos túbulos seminíferos, coincidindo com a diminuição do IGS e com uma grande redução na espermatogênese. Em geral, a morfologia dos testículos e o desenvolvimento das classes de maturação de O. hepsetus no Reservatório de Lajes não diferiram de espécies similares em outros ambientes lênticos. Os menores valores do IGS para o reservatório oligotrófico de Lajes, quando comparados com lagos naturais eutróficos, sugerem que O. hepsetus pode estar alterando este aspecto de sua estratégia reprodutiva no ambiente artificial.


Assuntos
Animais , Masculino , Peixes/crescimento & desenvolvimento , Maturidade Sexual/fisiologia , Espermatogênese/fisiologia , Espermatozoides/crescimento & desenvolvimento , Testículo/crescimento & desenvolvimento , Espermatozoides/citologia
8.
Arq. bras. med. vet. zootec ; 57(supl.2): 261-263, set. 2005.
Artigo em Português | LILACS | ID: lil-432022

RESUMO

Larvae of Amblyomma cajennense (Fabricius, 1787), were obtained under laboratory conditions. The larvae were killed in hot water, preserved in 70° ethanol and prepared in definitive whole mounts. Two hundred larvae were examined under brightjield microscopy with an immersion objective in order to analyze the variation of the number of internal setae of the right and left side of the Haller's organ chamber with the purpose of utilize them as chaetotaxy parameter for specific diagnosis.


Assuntos
Carrapatos/química , Ixodidae/anatomia & histologia , Ixodidae/química , Larva/química
9.
Braz J Biol ; 65(1): 1-8, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16025897

RESUMO

We assessed spatial and seasonal changes in the diet of Oligosarcus hepsetus in order to describe the strategy developed by this species that allows their very high abundance in Lajes reservoir, Rio de Janeiro, Brazil. Fish samplings were carried out using gill nets, deployed during ca. 12 and 24 hours, between April 2001 and May 2002. A total of 289 individuals were examined, of which 97 showed gut contents. We used the index of relative importance (IRI) to compare probable dietary shifts, and the frequency of occurrence (% OC) to analyze possible ontogenetic influences on feeding. O. hepsetus showed carnivorous habits, feeding preferably on fish and insects, the latter of which occurred in 71.0% of the guts presenting contents. O. hepsetus consumed different items along the three reservoir zones: insects (61.0% IRI) and Cichla monoculus (38.9% IRI) in the lower zone; Lepidoptera (57.0% IRI) in the middle zone; and C. monoculus (77.0% IRI) in the upper zone. Food items changed seasonally with C. nonloculus predominating in autumn 2001, and Hymenoptera and Lepidoptera in the winter. In spring almost all food was Lepidoptera (99.8% IRI), while in the summer Hemiptera dominated in the diet. In autumn 2002 Hemiptera (97.0% IRI) was dominant, in significant contrast with the previous autumn. Individuals smaller than 190 mm SL fed heavily on insects, while fishes predominated in the diet of individuals larger than 190 mm SL. Shifts in prey-capture ability among length classes suggest decreasing intraspecific competition. A higher food plasticity seems to be the strategy employed by this opportunist species, which used food resources available in the reservoir.


Assuntos
Comportamento Alimentar/fisiologia , Peixes/fisiologia , Conteúdo Gastrointestinal , Animais , Brasil , Preferências Alimentares , Água Doce , Estações do Ano
10.
Braz J Biol ; 65(1): 169-77, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16025915

RESUMO

A histological analysis was performed of the ovarian development of Oligosarcus hepsetus (Cuvier, 1829), a medium-sized carnivorous Characiform species in the Lajes reservoir, Brazil. A total of 125 fishes, collected monthly between April 2001 and June 2002 were examined by routine macroscopic and histological techniques. Eight phases of the oocyte development were described, and 4 stages and 4 substages of gonadal development were proposed. Spawning in reservoirs, similarly to that in rivers, is in batches, which favors juvenile survival and suggests that the impoundment of this area did not influence the reproductive strategy of this very successful species in a dammed environment.


Assuntos
Meio Ambiente , Peixes/anatomia & histologia , Oócitos/crescimento & desenvolvimento , Ovário/citologia , Maturidade Sexual , Animais , Brasil , Feminino , Peixes/crescimento & desenvolvimento , Tamanho do Órgão , Ovário/crescimento & desenvolvimento , Estações do Ano
11.
Braz. j. biol ; 65(1): 1-8, Feb. 2005. mapas, tab, graf
Artigo em Inglês | LILACS | ID: lil-416964

RESUMO

Foram analisadas variações na dieta de O. hepsetus conforme comparações espaciais e sazonais, com o objetivo de descrever a estratégia desenvolvida por essa espécie que permite sua elevada abundância no reservatório de Lajes, Rio de Janeiro, Brasil. As amostras foram coletadas utilizando redes de espera com permanência aproximadamente de 12 e 24 horas, no período entre abril de 2001 e maio de 2002. Dos 289 exemplares capturados, 97 peixes continham alimento no estômago. A análise foi baseada no índice de importância relativa (IIR), enquanto eventuais influências ontogenéticas foram determinadas pela freqüência de ocorrência (% FO). O. hepsetus apresentou hábito alimentar carnívoro, alimentando-se preferencialmente de peixes e insetos. O item Insetos apresentou relevante participação na dieta, ocorrendo em 71% dos estômagos que continham alimento. O. hepsetus consumiu diferentes itens entre as três zonas do reservatório: insetos (61% IIR) e Cichla monoculus (38,9% IIR) na zona baixa; Lepidoptera (57% IIR) na zona intermediária; e C. monoculus (77% IIR) na zona alta. No geral, ocorreram diferenciações durante todo o ciclo sazonal, em que C. monoculus predominou no outono de 2001 e Hymenoptera e Lepidoptera, no inverno. Na primavera, a alimentação foi basicamente constituída por Lepidoptera (99,8% IIR), enquanto no verão, Hemiptera predominou na dieta. No outono de 2002 foi registrado 97% IIR para Hemiptera, diferindo do outono anterior. Indivíduos menores que 190 mm de comprimento-padrão (CP) consumiram preferencialmente insetos, enquanto os espécimes de maior tamanho (> 190 mm CP) alimentaram-se principalmente de peixes. Mudanças na captura de presas entre classes de tamanho sugerem diminuição da competição intra-específica. A alta plasticidade na alimentação parece ser uma estratégia usada por essa espécie oportunista, consumindo os recursos alimentares disponíveis no reservatório.


Assuntos
Animais , Comportamento Alimentar/fisiologia , Peixes/fisiologia , Conteúdo Gastrointestinal , Brasil , Preferências Alimentares , Água Doce , Estações do Ano
12.
Braz. j. biol ; 65(1): 169-177, Feb. 2005. ilus
Artigo em Inglês | LILACS | ID: lil-416981

RESUMO

O desenvolvimento ovariano do peixe-cachorro Oligosarcus hepsetus (Cuvier, 1829), um characiforme carnívoro de pequeno a médio porte, foi analisado macro e microscopicamente. Um total de 125 espécimes, coletados mensalmente entre abril de 2001 e junho de 2002, foram examinados. Oito fases de desenvolvimento ovocitário foram descritas e quatro estágios e quatro substágios de desenvolvimento gonadal foram propostos. O. hepsetus apresenta desova do tipo parcelada no reservatório de Lajes, sugerindo que a estratégia reprodutiva da espécie não foi influenciada por eventuais mudanças físicas e químicas no ecossistema aquático causadas pelo represamento. O elevado grau de sucesso dessa espécie na represa e sua elevada abundância reforçam essa hipótese.


Assuntos
Animais , Feminino , Meio Ambiente , Peixes/anatomia & histologia , Oócitos/crescimento & desenvolvimento , Ovário/citologia , Maturidade Sexual , Brasil , Peixes/crescimento & desenvolvimento , Tamanho do Órgão , Ovário/crescimento & desenvolvimento , Estações do Ano
13.
Folha méd ; 106(4): 149-50, abr. 1993. tab
Artigo em Português | LILACS | ID: lil-154124

RESUMO

O extrato de Ginkgo biloba é um poderoso agente na terapia dos distúrbios vasculares (centrais ou apenas periféricos). É também um destruidor de radicais livres, em experiências com isquemia-reperfusäo intestinal, e um potente inibidor do PAF. No presente trabalho em camundongo normal, a sua açäo antilipoperoxidativa pode ser observada, quando ministrado com água


Assuntos
Animais , Masculino , Camundongos , Radicais Livres , Ginkgo biloba , Edema Encefálico , Fator de Ativação de Plaquetas/antagonistas & inibidores , Radicais Livres/antagonistas & inibidores , Extratos Vegetais/uso terapêutico
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