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1.
J Appl Microbiol ; 130(1): 90-99, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32640074

RESUMO

AIMS: This work aimed to estimate the growth of Myceliophthora thermophila M.7·7 in solid-state cultivation (SSC) through quantification of N-acetyl-d-glucosamine (NAG) and enzyme activity. METHODS AND RESULTS: The fungus was cultivated in sugarcane bagasse and wheat bran. A consistent statistical analysis was done to assess the reliability of experimental data. Logistic model equation was fitted to experimental data and growth parameters were estimated. The results showed strong influence of the sample size on NAG and a minimum recommended sample size was identified. Scanning electron microscopy (SEM) was used to identify the strategy of substrate colonization. Wheat bran was attacked firstly, while sugarcane bagasse was consumed after wheat bran depletion. The biomass growth was poorly estimated by secretion kinetics of α-amylase, endoglucanase, protease and xylanase, but enzyme kinetics were important for understanding substrate colonization. CONCLUSIONS: In conclusion, the NAG concentration was strongly affected by the sample size and sampling procedure. The strategy of fungal colonization on the substrates was well characterized through SEM analysis. The colonization strategy has direct influence on the kinetic parameters of the logistic model. Myceliophthora thermophila has a well-defined dynamic of enzyme secretion to degrade the substrate, although the kinetics of enzyme secretion has shown not adequate to characterize the kinetics of fungal growth. SIGNIFICANCE AND IMPACT OF THE STUDY: The paper provides reliable growth kinetic parameters in the SSC of the cellulase producer fungus M. thermophila M.7·7, as well as a robust analysis on three indirect methods (NAG, enzymes and SEM) for estimation of fungal development.


Assuntos
Sordariales/crescimento & desenvolvimento , Acetilglucosamina/metabolismo , Biomassa , Reatores Biológicos , Celulose/metabolismo , Fibras na Dieta/metabolismo , Proteínas Fúngicas/metabolismo , Cinética , Reprodutibilidade dos Testes , Saccharum/química , Sordariales/enzimologia , Sordariales/metabolismo , Sordariales/ultraestrutura
2.
Reprod Fertil Dev ; 33(5): 372-380, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33684338

RESUMO

This study evaluated the effects of three maturation systems, namely invitro (MatV) and invivo (MatS) systems, as well as intrafollicular transfer of immature oocytes (IFIOT; MatT), on the accumulation of lipid droplets in bovine oocytes. Lipids were evaluated using confocal microscopy and transmission electron microscopy. The expression of genes related to lipid metabolism, namely acyl-CoA synthetase short chain family member 2 (ACSS2), ELOVL fatty acid elongase 1 (ELOVL1) and fatty acid binding protein 3 (FABP3), was quantified by quantitative polymerase chain reaction. The mean (±s.d.) area occupied by lipids in immature oocytes (13±2%) was similar to those matured invivo (MatS, 16±2%; MatT, 12±2%). However, there was a significant increase in lipids in oocytes in the MatV group (24±2%) compared with all other groups (P<0.001). In the ultrastructural evaluations, MatV oocytes also showed the highest lipid content. The expression of ELOVL1 and FABP3 was similar in the MatS and IFIOT groups. However, transcript levels of ACSS2 were lower in IFIOT than MatV oocytes. These results indicate, for the first time, that oocytes matured by IFIOT are similar to those matured invivo with regard to lipid accumulation, which indicates better quality than those matured invitro.


Assuntos
Bovinos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Metabolismo dos Lipídeos , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Acetato-CoA Ligase/genética , Animais , Proteína 3 Ligante de Ácido Graxo/genética , Elongases de Ácidos Graxos/genética , Feminino , Expressão Gênica , Metabolismo dos Lipídeos/genética , Oócitos/ultraestrutura , Folículo Ovariano/citologia
3.
Reprod Fertil Dev ; 32(7): 690-696, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32317093

RESUMO

We aimed to analyse the histone acetylation status and expression profile of genes involved in histone acetylation (histone acetyltransferase 1 (HAT1), lysine acetyltransferase 2A (KAT2A), histone deacetylase 1(HDAC1), HDAC2 and HDAC3) in bovine oocytes of different competences during invitro maturation (IVM). Cumulus-oocyte complexes were recovered from two groups of follicles: minor follicles (1.0-3.0mm in diameter), classified as low competence (LC) and large follicles (6.0-8.0mm in diameter) classified as high competence (HC). Oocytes were submitted to IVM for 0, 8 and 24h and stored for analysis. Acetylation status of histone H4 on lysine K5, K6, K12 and K16 was assessed by immunohistochemistry. For gene expression, mRNA levels were determined by real-time quantitative polymerase chain reaction. All oocytes, regardless of their competence, showed a gradual decrease (P<0.05) in acetylation signals during IVM. From 0 to 8h of maturation, an increase (P<0.05) in the relative abundance of HAT1 mRNA was observed only in the HC oocytes. In this group, higher (P<0.05) mRNA levels of HDAC1 at 8h of maturation were also observed. In conclusion, in the present study, LC oocytes were shown to have adequate acetylation levels for the resumption and progression of meiosis; however, these oocytes do not have the capacity to synthesise RNA during IVM as the HC oocytes do.


Assuntos
Bovinos , Histona Acetiltransferases/metabolismo , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/enzimologia , Acetilação , Animais , Células do Cúmulo/fisiologia , Feminino , Histona Acetiltransferases/genética , Histonas/metabolismo , Lisina/metabolismo , Oócitos/crescimento & desenvolvimento , Oogênese/genética , Oogênese/fisiologia , RNA Mensageiro/análise
4.
Exp Parasitol ; 197: 36-42, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30633915

RESUMO

Molecules from natural sources, such as essential oils, have shown activity against parasites in vitro, but have not yet been explored extensively in vivo. Anethole and carvone (10% each), encapsulated with 80% of a solid matrix, referred to as EO (encapsulated oils), were tested in vivo in 2 experiments. In Experiment 1: Lambs were artificially infected with multidrug resistant Haemonchus contortus, or left uninfected, and treated (or not) with 50 mg/kg bw (body weight) of EO in a controlled environment. Thirty-two male lambs were kept in individual cages for a period of 45 days, after which animals were evaluated for parasitological, hematological, toxicological, and nutritional parameters. After 45 days of treatment, EO at 50 mg/kg bw provided a significant (P ≤ 0.05) reduction in fecal egg count (FEC). Although FEC was reduced, animals from both treatments had similar counts of total adult worms. The low FEC was caused probably by a significant reduction (P ≤ 0.05) in both male worm size and female fecundity. Dry matter intake of uninfected controls was significantly (P ≤ 0.05) reduced, although no toxicity was observed in treated animals. Thus, in Experiment 2, conducted for five months we used an EO dose of 20 mg/kg bw. Thirty-four weaned lambs, free of parasites, were divided in two groups and kept in collective pens. One group received EO at 20 mg/kg bw mixed with concentrate for 5 months and the other was kept as a control group (CTL). Parasitological and hematological parameters as well as body weight were evaluated. In the first 2.5 months, CTL and EO groups were confined, and both presented similar clinical parameters. Then, animals were allotted to graze on contaminated pastures to acquire natural infection for the next 2.5 months. The infection was patent after 25 days and both groups had similar decreases in weight gain, increases in FEC, and decreases in blood parameters. Coprocultures from CTL and EO groups established that parasite population was 90% Haemonchus sp. We concluded that the technology of encapsulation is safe and practical to deliver to lambs at the farm level and anethole and carvone at 50 mg/kg bw caused a significant decrease in FEC and, consequently, in pasture contamination by free living stages of H. contortus. However, EO at 20 mg/kg bw was not effective to prevent or treat sheep naturally-infected with gastrointestinal nematodes.


Assuntos
Anisóis/uso terapêutico , Hemoncose/veterinária , Monoterpenos/uso terapêutico , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/parasitologia , Abomaso/parasitologia , Derivados de Alilbenzenos , Animais , Anisóis/administração & dosagem , Anisóis/química , Aspartato Aminotransferases/sangue , Cápsulas , Creatinina/sangue , Monoterpenos Cicloexânicos , Resistência a Múltiplos Medicamentos , Sinergismo Farmacológico , Ingestão de Alimentos , Contagem de Eritrócitos/veterinária , Fezes/parasitologia , Feminino , Fertilidade , Hemoncose/tratamento farmacológico , Hemoncose/parasitologia , Haemonchus/efeitos dos fármacos , Haemonchus/crescimento & desenvolvimento , Haemonchus/fisiologia , Masculino , Monoterpenos/administração & dosagem , Monoterpenos/química , Contagem de Ovos de Parasitas/veterinária , Distribuição Aleatória , Ovinos , Ureia/sangue , Aumento de Peso , gama-Glutamiltransferase/sangue
5.
Parasitol Res ; 117(3): 705-712, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29327323

RESUMO

Albendazole (ABZ), a benzimidazole widely used to control gastrointestinal parasites, is poorly soluble in water, resulting in variable and incomplete bioavailability. This has favored the appearance ABZ-resistant nematodes and, consequently, an increase in its clinical ineffectiveness. Among the pharmaceutical techniques developed to increase drug efficacy, cyclodextrins (CDs) and other polymers have been extensively used with water-insoluble pharmaceutical drugs to increase their solubility and availability. Our objective was to prepare ABZ formulations, including ß-cyclodextrin (ßCD) or hydroxypropyl-ß-cyclodextrin (HPßCD), associated or not to the water-soluble polymer polyvinylpyrrolidone (PVP). These formulations had their solubility and anthelmintic effect both evaluated in vitro. Also, their anthelmintic efficacy was evaluated in lambs naturally infected with gastrointestinal nematodes (GIN) through the fecal egg count (FEC) reduction test. In vitro, the complex ABZ/HPßCD had higher solubility than ABZ/ßCD. The addition of PVP to the complexes increased solubility and dissolution rates more effectively for ABZ/HPßCD than for ABZ/ßCD. In vivo, 48 lambs naturally infected with GIN were divided into six experimental groups: control, ABZ, ABZ/ßCD, ABZ/ßCD-PVP, ABZ/HPßCD, and ABZ/HPßCD-PVP. Each treated animal received 10 mg/kg of body weight (based on the ABZ dose) for three consecutive days. After 10 days of the last administered dose, treatment efficacy was calculated. The efficacy values were as follows: ABZ (70.33%), ABZ/ßCD (85.33%), ABZ/ßCD-PVP (82.86%), ABZ/HPßCD (78.37%), and ABZ/HPßCD-PVP (43.79%). In vitro, ABZ/HPßCD and ABZ/HPßCD-PVP had high solubility and dissolution rates. In vivo, although the efficacies of ABZ/ßCD, ABZ/ßCD-PVP, and ABZ/HPßCD increased slightly when compared to pure ABZ, this increase was not significant (P > 0.05).


Assuntos
Albendazol/farmacocinética , Antiparasitários/farmacocinética , Ciclodextrinas/farmacocinética , Nanopartículas/química , Povidona/farmacocinética , 2-Hidroxipropil-beta-Ciclodextrina/química , 2-Hidroxipropil-beta-Ciclodextrina/farmacocinética , Albendazol/química , Animais , Anti-Helmínticos/química , Anti-Helmínticos/farmacocinética , Antiparasitários/química , Disponibilidade Biológica , Ciclodextrinas/química , Composição de Medicamentos , Enteropatias Parasitárias/tratamento farmacológico , Enteropatias Parasitárias/veterinária , Masculino , Nematoides , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/veterinária , Povidona/química , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/parasitologia , Solubilidade , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacocinética
6.
Int J Cosmet Sci ; 40(4): 408-419, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30047992

RESUMO

OBJECTIVE: Human hair is an element with unquestionable relevance in society both for women and men. Therefore, it is of great importance to develop new cosmetic products for hair care capable to restore and improve hair's characteristics. Here, we explore the potential of keratin-based particles in the protection and recovery of hair mechanical properties and thermal stability. METHODS: Keratin-based particles were obtained by high pressure homogenization (HPH) using keratin and silk fibroin. The particles were characterized regarding size, superficial charge and polydispersity index. Their safety to cells was assessed using human skin keratinocytes. Virgin and overbleached Asian hair were treated with eight keratin-based formulations. The effect of particles on hair's mechanical properties was evaluated in terms of stiffness and tensile strength. The impact of treatments in hair thermal performance was studied using differential scanning calorimetry (DSC). RESULTS: Keratin-based particles were capable to recover and/or improve the mechanical properties of virgin and overbleached hair. Virgin hair treated with K80 SF20 P particles presented an improvement in the mechanical properties of around 40%. An increase in keratin α-helix denaturation enthalpy and in surface smoothness for both types of hair was also verified after treatment. These particles demonstrated stability over time and proved to be safe when tested in human keratinocytes. CONCLUSION: The keratin-based particles here presented have the potential to be incorporated in the development of new and effective hair care cosmetic formulations.


Assuntos
Preparações para Cabelo , Cabelo/efeitos dos fármacos , Queratinas/administração & dosagem , Povo Asiático , Varredura Diferencial de Calorimetria , Linhagem Celular , Feminino , Humanos , Queratinócitos/efeitos dos fármacos , Queratinas/química , Queratinas/farmacologia , Masculino , Microscopia Eletrônica de Transmissão e Varredura , Estrutura Secundária de Proteína , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração
7.
Med Oral Patol Oral Cir Bucal ; 23(1): e65-e71, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29274162

RESUMO

BACKGROUND: To compare the analgesic effect of anesthetic infiltration of lidocaine 2% and low-level laser therapy (LLLT) by GaAlAs into tender points of patients with orofacial pain and fibromyalgia (FM). MATERIAL AND METHODS: A randomized clinical trial was performed with adults (N=66) that were allocated into two groups (1:1): Group A received LLLT irradiation by Diode Laser GaAlAs (780nm) with expositions twice a week during six weeks and Group B was treated with anesthetic infiltration of lidocaine 2% without vasoconstrictor once a week for four weeks. The pain assessment included the Visual Analogic Scale (VAS) and tenderness to palpation. RESULTS: No dropout and adverse effect was observed during the study. The pain decreased significantly in each group after the treatment (p=0.0001, ß=1.0), even though no statistical difference was found between both treatments (p=0.46, ß= 0.82). The presence of tender points decreased after both treatments, with responsively in some types of masticatory muscles (p<0.05) except posterior temporalis muscle. The patients perception showed that both treatments were effective and a few patients reported that the treatment did not improve welfare. CONCLUSIONS: The LLLT by GaAlAs and anesthetic infiltration of lidocaine 2% were equally effective to control orofacial pain in FM individuals.


Assuntos
Anestesia Local , Anestésicos Locais/administração & dosagem , Dor Facial/etiologia , Dor Facial/radioterapia , Fibromialgia/complicações , Lasers Semicondutores/uso terapêutico , Lidocaína/administração & dosagem , Terapia com Luz de Baixa Intensidade , Manejo da Dor/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
J Evol Biol ; 30(7): 1336-1346, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28434197

RESUMO

Sexual traits (e.g. visual ornaments, acoustic signals, courtship behaviour) are often displayed together as multimodal signals. Some hypotheses predict joint evolution of different sexual signals (e.g. to increase the efficiency of communication) or that different signals trade off with each other (e.g. due to limited resources). Alternatively, multiple signals may evolve independently for different functions, or to communicate different information (multiple message hypothesis). We evaluated these hypotheses with a comparative study in the family Estrildidae, one of the largest songbird radiations, and one that includes many model species for research in sexual selection and communication. We found little evidence for either joint evolution or trade-offs between song and colour ornamentation. Some negative correlations between dance repertoire and song traits may suggest a functional compromise, but generally courtship dance also evolved independently from other signals. Instead of correlated evolution, we found that song, dance and colour are each related to different socio-ecological traits. Song complexity evolved together with ecological generalism, song performance with investment in reproduction, dance with commonness and habitat type, whereas colour ornamentation was shown previously to correlate mostly with gregariousness. We conclude that multimodal signals evolve in response to various socio-ecological traits, suggesting the accumulation of distinct signalling functions.


Assuntos
Cor , Tentilhões , Vocalização Animal , Animais , Evolução Biológica , Ecologia , Movimento , Comportamento Sexual Animal
9.
Bull Entomol Res ; 106(5): 663-71, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27296010

RESUMO

During host selection, physical and chemical stimuli provide important cues that modify search behaviours of natural enemies. We evaluated the influence of volatiles released by eggs and egg extracts of the stink bug Euschistus heros and by soybean plants treated with the eggs and egg extracts on Telenomus podisi foraging behaviour. Responses to volatiles were evaluated in Y-tube olfactometers after exposure to (1) one egg cluster for 24 h; (2) plants with eggs laid by the stink bug, tested at 24, 48, and 72 h after treatment; (3) plants with eggs laid artificially, tested at 24, 48, and 72 h after treatment; and (4) plants treated with acetone or hexane extracts of eggs. Telenomus podisi was attracted to volatiles emitted by one egg cluster and to acetone extracts of one egg cluster, but not to air or acetone controls. There were no responses to odours of plants treated with eggs or egg extracts. Analysis of acetone extracts of egg clusters by gas chromatography revealed the major components were saturated and unsaturated fatty acids, including hexadecanoic acid, linoleic acid, and (Z)-9-octadecenoic acid. Our results suggest that one egg cluster and the acetone extract of one egg cluster contain volatile compounds that can modify T. podisi foraging behaviour, and that the amounts of these compounds, probably together with some minor compounds, are important for host recognition by T. podisi. Also, the oviposition damage or egg extracts on the plant did not elicit indirect defences that attracted Telenomus podisi.


Assuntos
Comportamento Animal , Glycine max/química , Heterópteros/química , Vespas/fisiologia , Animais , Misturas Complexas/química , Feminino , Heterópteros/parasitologia , Interações Hospedeiro-Parasita , Óvulo/química , Óvulo/parasitologia , Volatilização
10.
Biochim Biophys Acta ; 1838(10): 2555-67, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24976292

RESUMO

Dioctadecyldimethylammonium bromide (DODAB):Monoolein (MO) lipoplexes have mainly been studied within the range of high molar ratios of DODAB, with noticeable transfection efficiencies in the Human Embryonic Kidney (HEK, a.k.a. 293T) cell line. In this work, we intend to study the effect of high MO content on the structure and physicochemical properties of pDNA/DODAB:MO lipoplexes to achieve some correlation with their transfection efficiency. Static/Dynamic Light Scattering and Cryo-TEM imaging were used to characterize the size/morphology of DNA/DODAB:MO lipoplexes at different DODAB:MO contents (2:1, 1:1, 1:2) and charge ratios (CRs) (+/-). Nile Red fluorescence emission was performed to detect changes in microviscosity, hydration and polarity of DNA/DODAB:MO systems. Lipoplexes stability at physiological pH values and in the presence of anionic lipids was evaluated by Förster Resonance Energy Transfer (FRET). Physicochemical/structural data were complemented with transfection studies in HEK cells using the ß-galactosidase reporter gene activity assay. This work reports the coexistence of multilamellar and non-lamellar inverted phases in MO-richer lipoplexes (DODAB:MO 1:2 and 1:4), leading to transfection efficiencies comparable to those of multilamellar (DODAB-richer) lipoplexes, but at higher charge ratios [CR (+/-)=6.0] and without dose-effect response. These results may be related to the structural changes of lipoplexes promoted by high MO content.


Assuntos
DNA/química , Glicerídeos/química , Plasmídeos/química , Compostos de Amônio Quaternário/química , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Transfecção/métodos
11.
Int J Cosmet Sci ; 37(3): 282-90, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25565218

RESUMO

OBJECTIVE: Hair follicles are widely recognized as the preferential target and site of accumulation for nanoparticles after topical application. This feature is of particular importance for hair cosmetics, having the potential to refine the treatment of several hair follicle-related disorders. The aim of this work was to improve the preparation of Poly (D,L-lactide) (PLA) nanoparticles for in vivo follicular target and drug delivery. METHODS: Envisaging a future industrial scale-up of the process, nanoprecipitation method was used to prepare PLA nanoparticles: the effect of several processing parameters on their properties was examined and the yield of nanoparticles formation determined. Encapsulation efficiencies and in vitro release profiles of lipophilic and hydrophilic model compounds were also assessed. In vitro cytotoxicity and ex vivo penetration studies were performed on a reference skin cell line (NCTC2455, human skin keratinocytes) and porcine skin, respectively. RESULTS: Using acetone : ethanol (50 : 50, v/v) as the solvent phase, 0.6% (w/w) of Pluronic(®) F68 as a surfactant agent and agitation to mix the solvent and non-solvent phases, a monodispersed population of non-cytotoxic spherical nanoparticles of approximately 150 nm was obtained. The yield of nanoparticles for this formulation was roughly 90%. After encapsulation of model compounds, no significant changes were found in the properties of particles and the entrapment efficiencies were above 80%. The release kinetics of dyes from PLA nanoparticles indicate an anomalous transport mechanism (diffusion and polymer degradation) for Nile Red (lipophilic) and a Fickian diffusion of first order for fluorescein 5(6)-isothiocyanate (hydrophilic). Ex vivo skin penetration studies confirmed the presence of nanoparticles along the entire follicular ducts. CONCLUSIONS: The optimized method allows the preparation of ideal PLA nanoparticles-based formulations for hair follicle targeting. PLA nanoparticles can effectively transport and release lipophilic and hydrophilic compounds into the hair follicles, and the yields obtained are acceptable for industrial purposes.


Assuntos
Folículo Piloso/efeitos dos fármacos , Nanopartículas , Poliésteres/farmacologia , Animais , Linhagem Celular , Humanos , Solventes/química , Tensoativos/química , Suínos
12.
Cryobiology ; 69(2): 256-65, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25106744

RESUMO

This study aimed to investigate the functional, morphological and molecular patterns of bovine oocytes vitrified at different times during in vitro maturation (IVM). Four groups of oocytes were used: non-vitrified control oocytes (CG), oocytes vitrified at 0 h (V0), oocytes vitrified after 8 h of IVM (V8) and oocytes vitrified after 22 h of IVM (V22). After vitrification, the oocytes were warmed and then returned to the incubator to complete a total of 24h of IVM. To evaluate the effect of vitrification, the nuclear maturation and fertilization rates were assessed by lacmoid staining and ultrastructural electron microscopy. The cleavage and blastocyst rates were evaluated at D2, D7 and D8. The expression levels of CASP3, TP53, HDAC2, SUV39H1 and DNMT1 were investigated by RT-qPCR. The nuclear maturation, oocyte fertilization, cleavage and blastocyst rates were higher (P < 0.05) in the CG group (80%; 81.3%; 88.5%; and 35.8%) than in the V0 (44%; 44.6%; 22.7%; and 2.6%), V8 (50%; 63%; 21.5%; and 2.2%) and V22 (55.5%; 66.9%; 24.1%; and 4.6%) groups. Ultrastructural analysis revealed significant damage within the cytoplasm of all vitrified groups, but more severe degeneration was observed in the V22 group. The gene expression profiles were not affected by vitrification (P > 0.05). In conclusion, cytoplasm degeneration seems to be the most severe form of damage caused by vitrification. The use of the Cryotop method for vitrification severely reduces bovine oocyte viability regardless of whether it is performed at GV, GVBD or MII stage.


Assuntos
Criopreservação/veterinária , Oócitos/citologia , Vitrificação , Animais , Blastocisto/citologia , Bovinos , Criopreservação/métodos , Feminino , Fertilização in vitro , Perfilação da Expressão Gênica , Meiose , Oócitos/metabolismo , Oócitos/ultraestrutura
13.
Heart Fail Rev ; 18(2): 219-49, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22446984

RESUMO

Heart failure (HF) is one of the major health and economic burdens worldwide, and its prevalence is continuously increasing. The study of HF requires reliable animal models to study the chronic changes and pharmacologic interventions in myocardial structure and function and to follow its progression toward HF. Indeed, during the past 40 years, basic and translational scientists have used small animal models to understand the pathophysiology of HF and find more efficient ways of preventing and managing patients suffering from congestive HF (CHF). Each species and each animal model has advantages and disadvantages, and the choice of one model over another should take them into account for a good experimental design. The aim of this review is to describe and highlight the advantages and drawbacks of some commonly used HF rodents models, including both non-genetically and genetically engineered models, with a specific subchapter concerning diastolic HF models.


Assuntos
Modelos Animais de Doenças , Terapia Genética/métodos , Insuficiência Cardíaca/terapia , Animais , Insuficiência Cardíaca/fisiopatologia , Miocárdio , Roedores
14.
Int J Cosmet Sci ; 35(4): 368-74, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23574448

RESUMO

OBJECTIVES: Physical appearance has significant importance psychologically and socially, with skin and hair being of prime relevance. Effective ingredients that modulate melanin synthesis are of growing interest. Tamoxifen, a widely used selective oestrogen receptor modulator, SERM, was described occasionally in medical case reports as causing grey hair repigmentation. This work aimed to study, in vitro, the effect of tamoxifen and 4-hydroxy-tamoxifen, one of its most bioactive derivatives, on melanin production in human melanocytes. METHODS: Adult normal human epidermal melanocytes (NHEM) were treated with physiological concentrations of tamoxifen and 4-hydroxy-tamoxifen during 72 hours. Cytotoxicity was evaluated by lactate dehydrogenase (LDH) leakage. Total melanin was quantified by spectrophotometry, and cyclic adenosine monophosphate (cAMP) was determined by competitive ELISA. The relative mRNA levels of several genes involved in melanogenesis were investigated by real-time PCR. RESULTS: Under the conditions used, the results showed that tamoxifen and 4-hydroxy-tamoxifen treatments, none of them toxic to NHEM, induced a time-dependent increase in the amount of melanin released to the culture medium. cAMP, one of the major second messenger in signalling pathways important to melanogenesis, was decreased after treatment. The transcript levels of genes coding for catalase, premelanosome protein and melan-A, directly related to skin and hair pigmentation, showed an increased tendency upon tamoxifen and 4-hydroxy-tamoxifen treatment. Induction of catalase gene expression in NHEM points towards a promelanogenic effect mediated by ROS. CONCLUSION: According to the results, even in such a short treatment period, tamoxifen and 4-hydroxy-tamoxifen promoted melanin extrusion and they seem to act as melanogenesis stimulators at the molecular level. Our data suggest that SERMs might be a new tool for increasing melanogenesis and might be of great interest for topical formulations in cosmetic industry.


Assuntos
Melaninas/biossíntese , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Tamoxifeno/farmacologia , Adulto , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Humanos , Técnicas In Vitro , Reação em Cadeia da Polimerase em Tempo Real
15.
Int J Cosmet Sci ; 35(5): 458-66, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23651449

RESUMO

OBJECTIVES: The objective of this work was to develop a new strategy to physically 'repair' chemically damaged hair. Hence the human eye γD-crystallin, a protein from the superfamily characterized structurally by the Greek key motif, was studied. The human γD-crystallin was chosen based on the ability of proteins belonging to this superfamily to be involved in the coating of specific structures. Two crystallins were used on the study, the wild type (Protein Data Bank ID: 1HK0) and the mutant protein. The mutant form was intended to induce a strong and quick protein polymerization as well to have new possible points of anchorage to hair. METHODS: The ability of both crystallins to bind to damaged hair and even penetrate into its cortex was checked by fluorescence microscopy, confocal microscopy and scanning electron microscopy. Furthermore the reinforcement of hair mechanical resistance, the potential cytotoxic/inflammatory effect of crystallins were studied in order to have a fully comprehension about the protein based formulation. RESULTS: Although the chemical over-bleaching treatment induced a decrease of 20% on the resistance of the hair, the crystallins which bind and penetrate the hair fibre were able to recover and even to improve its mechanical properties when compared to the virgin hair. Moreover none of the crystallins displayed a toxic effect in fibroblasts for all the range of tested concentrations upon 72 h of exposure. The active aggregation process of mutant crystallin induced an inflammatory response in fibroblasts in the first 24 h of contact, measured by the amount of released pro-inflammatory cytokine IL-6 to the medium. In contrast contact with wild type crystallin did not lead to significant inflammation. CONCLUSION: Outcome from protein formulation characterization supports the hypothesis that the γD-crystallin it is able to recover and improve the mechanical properties of chemical damaged hair. Therefore it can be considered as a very promising strengthening agent for the development of new restorative hair care products.


Assuntos
Preparações para Cabelo/farmacologia , Cabelo/metabolismo , gama-Cristalinas/farmacologia , Sequência de Bases , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cabelo/efeitos dos fármacos , Cabelo/ultraestrutura , Humanos , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Modelos Moleculares , Dados de Sequência Molecular , Resistência à Tração
16.
Int J Cosmet Sci ; 35(3): 244-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23301816

RESUMO

Human hair has an important and undeniable relevance in society due to its important role in visual appearance and social communication. Hair is mainly composed of structural proteins, mainly keratin and keratin associated proteins and lipids. Herein, we report a comprehensive study of the content and distribution of the lipids among ethnic hair, African, Asian and Caucasian hair. More interestingly, we also report the study of the interaction between those two main components of hair, specifically, the influence of the hair internal lipids in the structure of the hair keratin. This was achieved by the use of a complete set of analytical tools, such as thin layer chromatography-flame ionization detector, X-ray analysis, molecular dynamics simulation and confocal microscopy. The experimental results indicated different amounts of lipids on ethnic hair compositions and higher percentage of hair internal lipids in African hair. In this type of hair, the axial diffraction of keratin was not observed in X-ray analysis, but after hair lipids removal, the keratin returned to its typical packing arrangement. In molecular dynamic simulation, lipids were shown to intercalate dimers of keratin, changing its structure. From those results, we assume that keratin structure may be influenced by higher concentration of lipids in African hair.


Assuntos
Etnicidade , Cabelo/química , Queratinas/análise , Cromatografia em Camada Fina , Humanos , Microscopia Confocal , Simulação de Dinâmica Molecular , Difração de Raios X
17.
Water Sci Technol ; 68(10): 2214-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24292470

RESUMO

Biodegradability enhancement and detoxification of cork boiling wastewater (CBW) are required for the successful implementation of biological treatment options. We studied the possibility of achieving these goals through ozonation pre-treatment by experimenting on the effect of ozone dose and pH. The CBW used had a pH of 5.81, a chemical oxygen demand (COD) of 1,865 mg L(-1), a biochemical oxygen demand (BOD5) of 498 mg L(-1) and total phenol (TP) and tannin compounds concentrations of 523 and 399 mg L(-1), respectively. The ozone doses ranged from 0.27 to 2.63 for the O3(applied)/COD0 ratios with samples at natural pH and set to 3.33 and 9.96. Ozonation allowed the BOD20/COD ratio (biodegradability index) to increase from 0.37 to 0.63 and a toxicity reduction from 3.08 to 1.24 TU (Microtox). The corresponding removals obtained were 15.2-62.0%, 38.4-83.2% and 56.7-92.1% for COD, TP and colour, respectively. The best outcome of ozonation pre-treatment requires O3(applied)/COD0 ratios over 1.5 and an acid pH. The increase of TP removals with ozone dose at acid pH led to biodegradability enhancement and CBW detoxification. However, for similar conditions the highest COD removals were obtained at alkaline pH due to the hydroxyl radicals' high oxidation ability but lack of selectivity.


Assuntos
Ozônio/química , Águas Residuárias/química , Purificação da Água/métodos , Biodegradação Ambiental , Concentração de Íons de Hidrogênio
18.
Nat Commun ; 14(1): 1041, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36823200

RESUMO

Vaccination against human cytomegalovirus (CMV) infection remains high priority. A recombinant form of a protein essential for CMV entry, glycoprotein B (gB), demonstrated partial protection in a clinical trial (NCT00299260) when delivered with the MF59 adjuvant. Although the antibody titre against gB correlated with protection poor neutralising responses against the 5 known antigenic domains (AD) of gB were evident. Here, we show that vaccination of CMV seronegative patients induces an antibody response against a region of gB we term AD-6. Responses to the polypeptide AD-6 are detected in >70% of vaccine recipients yet in <5% of naturally infected people. An AD-6 antibody binds to gB and to infected cells but not the virion directly. Consistent with this, the AD-6 antibody is non-neutralising but, instead, prevents cell-cell spread of CMV in vitro. The discovery of AD-6 responses has the potential to explain part of the protection mediated by gB vaccines against CMV following transplantation.


Assuntos
Infecções por Citomegalovirus , Vacinas contra Citomegalovirus , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , Citomegalovirus , Infecções por Citomegalovirus/prevenção & controle , Vacinas contra Citomegalovirus/imunologia , Proteínas do Envelope Viral
19.
Biochim Biophys Acta ; 1808(10): 2440-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21787746

RESUMO

DNA/Cationic liposome complexes (lipoplexes) have been widely used as non-viral vectors for transfection. Neutral lipids in liposomal formulation are determinant for transfection efficiency using these vectors. In this work, we studied the potential of monoolein (MO) as helper lipid for cellular transfection. Lipoplexes composed of pDNA and dioctadecyldimethylammonium bromide (DODAB)/1-monooleoyl-rac-glycerol (MO) at different molar ratios (4:1, 2:1 and 1:1) and at different cationic lipid/DNA ratios were investigated. The physicochemical properties of the lipoplexes (size, charge and structure), were studied by Dynamic Light Scattering (DLS), Zeta Potential (ζ) and cryo-transmission electron microscopy (cryo-TEM). The effect of MO on pDNA condensation and the effect of heparin and heparan sulphate on the percentage of pDNA release from the lipoplexes were also studied by Ethidium Bromide (EtBr) exclusion assays and electrophoresis. Cytotoxicity and transfection efficiency of these lipoplexes were evaluated using 293T cells and compared with the golden standard helper lipids 1,2-dioleoyl-sn-glycero-3-hosphoethanolamine (DOPE) and cholesterol (Chol) as well as with a commercial transfection agent (Lipofectamine™ LTX). The internalization of transfected fluorescently-labeled pDNA was also visualized using the same cell line. The results demonstrate that the presence of MO not only increases pDNA compactation efficiency, but also affects the physicochemical properties of the lipoplexes, which can interfere with lipoplex-cell interactions. The DODAB:MO formulations tested showed little toxicity and successfully mediated in vitro cell transfection. These results were supported by fluorescence microscopy studies, which illustrated that lipoplexes were able to access the cytosol and deliver pDNA to the nucleus. DODAB:MO-based lipoplexes were thus validated as non-toxic, efficient lipofection vectors for genetic modification of mammalian cells. Understanding the relation between structure and activity of MO-based lipoplexes will further strengthen the development of these novel delivery systems.


Assuntos
Vetores Genéticos , Glicerídeos/química , Compostos de Amônio Quaternário/química , Transfecção , Microscopia Crioeletrônica , Lipossomos , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência
20.
Int J Cosmet Sci ; 34(4): 338-46, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22515553

RESUMO

A peptide based on a fragment of hair keratin type II cuticular protein, keratin peptide (KP), was studied as a possible strengthening agent for weakened relaxed hair. The peptide was prepared both in aqueous water formulation (WF) and organic solvent formulations (OF), to determine the effect of organic solvents on peptide interaction with hair and the differences in hair recovery. Both peptide formulations were shown to improve mechanical and thermal properties of weakened hair with peptide in OF showing the stronger effect. As a potential new hair care product, and so would necessitate contact with skin, the cytotoxicity and genotoxicity of the peptide were also evaluated through different methodologies (Alamar Blue assay, 2'-7'-dichlorofluorescein probe, cell morphology and growth and evaluation of DNA damage by an alkaline version of the comet assay) in skin fibroblasts. These tests are indicators of the potential of peptide to cause irritation on skin or to be carcinogenic, respectively. The peptide in WF did not cause cytotoxicity or genotoxicity in any of the concentrations tested. The presence of OF, however, induced a 20% decrease in cell viability in all of the range of concentrations used after 72-h incubation. Moreover, OF inhibited cell growth and was considered genotoxic at first contact with cells. The peptide was therefore considered a promising strengthening agent for hair and was shown to be innocuous when applied in WF.


Assuntos
Preparações para Cabelo/administração & dosagem , Cabelo/efeitos dos fármacos , Queratinas/administração & dosagem , Negro ou Afro-Americano , Varredura Diferencial de Calorimetria , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Dano ao DNA , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Cabelo/metabolismo , Cabelo/ultraestrutura , Humanos , Microscopia de Contraste de Fase , Testes de Mutagenicidade , Resistência à Tração
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