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1.
Zygote ; 30(3): 419-422, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34689852

RESUMO

The aim of this study was to evaluate the effect of 1 µmol/l zearalenone (ZEN) and 1 µmol/l matairesinol (MAT), alone or in combination, on the morphology of in vitro-cultured ovarian preantral follicles. Ovaries from four adult sheep were collected at a local slaughterhouse and fragmented, and the ovarian pieces were submitted to in vitro culture for 3 days in the presence or absence of the test compounds. The morphology of primordial and primary follicles was impaired by ZEN. The plant lignan MAT alone did not maintain the morphology of the ovarian follicles; its combination with ZEN counteracted the negative effects observed when follicles were cultured in the presence of the mycotoxin alone. However, MAT was not able to promote the in vitro development of the ovarian follicles.


Assuntos
Lignanas , Zearalenona , Animais , Feminino , Furanos , Lignanas/farmacologia , Folículo Ovariano , Ovário , Ovinos , Zearalenona/toxicidade
2.
Breast Cancer Res Treat ; 157(1): 1-11, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27097608

RESUMO

One of the cancer molecular hallmarks is a deviant energetic metabolism, known as the Warburg effect, whereby the rate of glucose uptake is significantly increased and a high rate of glycolysis and lactic acid production occurs even when oxygen is present-"aerobic lactatogenesis". Accordingly, GLUT1 and MCT1, which are the main glucose and lactate transporters in cancer cells, respectively, have been proposed as oncogenes and are currently seen as potential therapeutic targets in cancer treatment. Polyphenols, commonly contained in fruits and vegetables, have long been associated with a protective role against cancer. Generally considered as nontoxic, dietary polyphenols are considered ideal chemopreventive and possibly chemotherapeutic agents. Several mechanisms of action of polyphenols in breast cancer cells have been proposed including modulation of intracellular signaling, induction of apoptosis through redox regulation or modulation of epigenetic alterations. Additionally, in vitro studies have shown that several polyphenols act as specific inhibitors of glucose transport in breast cancer cell lines and an association between their anticarcinogenic effect and inhibition of glucose cellular uptake has been described. Also, some polyphenols were found to inhibit lactate transport. Importantly, some polyphenols behave as inhibitors of both glucose and lactate cellular uptake by breast cancer cells and these compounds are thus very interesting in the context of a chemopreventive effect, because they deplete breast cancer cells of their two most important energy suppliers. So, the antimetabolic effect of polyphenols should be regarded as a mechanism of action contributing to their chemopreventive/chemotherapeutic potential in relation to breast cancer.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Glucose/metabolismo , Ácido Láctico/metabolismo , Polifenóis/farmacologia , Antineoplásicos/uso terapêutico , Transporte Biológico/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/prevenção & controle , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Transportador de Glucose Tipo 1/metabolismo , Humanos , Transportadores de Ácidos Monocarboxílicos/metabolismo , Polifenóis/uso terapêutico , Simportadores/metabolismo
3.
Genet Mol Res ; 15(3)2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27706782

RESUMO

The aim of this study was to identify inbred progenies of S0:1 maize (Zea mays L.) plants that were efficient at a low level of technology and responsive at a high level of technology through the use of topcrosses. Two contrasting environments were created using two levels of base fertilization and topdressing, so that the levels of nitrogen, phosphorus, and potassium were applied four times higher in one environment than in the other. We used S0:1 progenies derived from commercial hybrids in topcrosses with two testers (an elite line from the flint heterotic group and an elite line from the dent heterotic group). The progenies and three controls were evaluated in an augmented block design in Nossa Senhora das Dores, SE, Brazil in the 2010 crop season. The average grain yield in the high-technological level was 21.44% greater than that in the low-technological level. There were no changes in progeny behavior in the two technological levels for grain yield. The testers did not differ in the average grain yield of the progenies at the two technological levels. Therefore, it is possible to select progenies derived from commercial hybrids that have an efficient response to fertilization.


Assuntos
Cruzamentos Genéticos , Meio Ambiente , Endogamia , Seleção Genética , Zea mays/genética , Alelos , Zea mays/anatomia & histologia
4.
Genet Mol Res ; 15(3)2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27706729

RESUMO

Disease-resistant potato cultivars with good tuber appearance and desirable agronomic traits are essential for meeting the demands of producers and the market. Attaining these cultivars is the focus of potato breeding programs whose aim is to benefit the productive chain. The purpose of this study was to estimate combining abilities and evaluate potato clones based on tuber appearance, yield, and resistance to the PVY and PVX viruses. Crosses between four commercial cultivars of potato with good tuber appearance were performed, using eight clones with proven resistance to PVY and PVX from the breeding program of UFLA. The clones obtained were evaluated for agronomic traits, tuber appearance, and the presence of both Ryadg and Rx1 alleles, which confer extreme resistance to the PVY and PVX viruses, respectively. The independent culling level method was used to select genotypes of commercial interest, as well as to estimate the combining abilities of the parents. We identified clones carrying the Ryadg and Rx1 alleles with agronomic traits suitable for the fresh market and for processing. The BRS Ana cultivar and CMA-399 and CMA-385 clones showed positive effects on general combining ability (GCA) for tuber yield, while the Monalisa cultivar showed positive effects on GCA for general tuber appearance.


Assuntos
Doenças das Plantas/genética , Potexvirus/genética , Potyvirus/genética , Solanum tuberosum/genética , Alelos , Cruzamento , Cruzamentos Genéticos , Resistência à Doença/genética , Genótipo , Imunidade Inata/genética , Fenótipo , Doenças das Plantas/virologia , Potexvirus/patogenicidade , Potyvirus/patogenicidade , Solanum tuberosum/virologia
5.
Genet Mol Res ; 14(2): 6472-81, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26125852

RESUMO

Attalea vitrivir Zona (synonym Orbignya oleifera) is one of the six species of Arecaceae known as "babassu". This species is used to make cosmetics, food, and detergents due to the high concentration of oil in the seeds. It is found only in fragmented areas of southern Bahia State and northern Minas Gerais State, southeast Brazil, and this fragmentation has affected both its ecological and genetic characteristics. We evaluated the genetic diversity and population genetic structure of A. vitrivir in six areas of two different regions at the extremes of its geographical range, in order to gain a better understanding of the factors that affect the distribution and partitioning of its diversity. Nine inter simple sequence repeat (ISSR) markers amplified 74 polymorphic bands, resulting in large diversity values (Shannon diversity index, 0.37-0.47; intrapopulation genetic diversity, 0.25-0.34). Analysis of molecular variance (AMOVA) revealed considerable differentiation between sampling sites (30.03%) and regions (12.08%), although most of the diversity was observed within sampling sites (69%). Further differentiation between sampling sites was noted more in the northern region than in the southern region, highlighting the genetic connectivity between the sampling sites within Rio Pandeiros Environmental Protection Area (southern region). The identification of two distinct genetic clusters (K = 2) corresponded to the northern and southern regions, and corroborated the AMOVA results. We suggest that the northern area, outside Rio Pandeiros Environmental Protection Area, must be included in future management plans for this species.


Assuntos
Arecaceae/genética , Variação Genética , Genética Populacional , Brasil , DNA de Plantas/genética , Genótipo , Repetições de Microssatélites , Filogenia
6.
Genet Mol Res ; 14(3): 8236-43, 2015 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-26345749

RESUMO

The objective of this study was to evaluate the performance of 119 full sib progenies of the fifth cycle of reciprocal recurrent selection (RRS) derived from of Universidade Federal de Lavras maize breeding program. The experiment was carried out in an 11 x 11 triple lattice design at two locations (Lavras, Lambari). The plots consisted of two rows of 3 m, with four plants per 1 m and 0.60 meters of spacing between lines. The grain yield was obtained as kg/plot through weighing of husked ears. The contrast between progenies and controls was not significant, indicating there were no significant differences among the average grain yields of the progenies and controls. When considering the joint analysis, heritability was 64.2%; however, this estimate did not differ from the values estimated for each location separately. Estimates of genetic and phenotypic variance among progenies ranged from 0.21 to 0.28 and 0.30 to 0.47, respectively. Estimates of selection gain, for 10% selection intensity, indicated gains of 16% in the joint analysis of the two locations. The progenies of the fifth cycle of RRS had high average grain yield, associated with high variability. In comparison to the average grain yields exhibited by the controls, it was concluded that the progenies have the potential to be commercially exploited.


Assuntos
Cruzamento , Locos de Características Quantitativas/genética , Seleção Genética/genética , Zea mays/genética , Produtos Agrícolas , Cruzamentos Genéticos , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Variação Genética , Zea mays/crescimento & desenvolvimento
7.
Genet Mol Res ; 13(2): 2906-13, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24634294

RESUMO

Lasiodiplodia theobromae is a major pathogen of many different crop cultures, including cashew nut plants. This paper describes an efficient Agrobacterium tumefaciens-mediated transformation (ATMT) system for the successful delivery of T-DNA, transferring the genes of green fluorescent protein (gfp) and hygromycin B phosphotransferase (hph) to L. theobromae. When the fungal pycnidiospores were co-cultured with A. tumefaciens harboring the binary vector with hph-gfp gene, hygromycin-resistant fungus only developed with acetosyringone supplementation. The cashew plants inoculated with the fungus expressing GFP revealed characteristic pathogen colonization by epifluorescence microscopy. Intense and bright green hyphae were observed for transformants in all extensions of mycelium cultures. The penetration of parenchyma cells near to the inoculation site, beneath the epicuticle surface, was observed prior to 25 dpi. Penetration was followed by the development of hyphae within invaded host cells. These findings provide a rapid and reproducible ATMT method for L. theobromae transformation.


Assuntos
Agrobacterium tumefaciens/genética , Anacardium/genética , Ascomicetos/genética , Nozes/genética , Anacardium/crescimento & desenvolvimento , Anacardium/microbiologia , Ascomicetos/patogenicidade , Técnicas de Transferência de Genes , Vetores Genéticos , Proteínas de Fluorescência Verde , Hifas/genética , Hifas/patogenicidade , Nozes/crescimento & desenvolvimento , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Transformação Genética
8.
Diabet Med ; 30(10): 1255-62, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23721292

RESUMO

AIM: The aim of this study was to determine the relationship between the daily frequency of self-monitoring of blood glucose and glycaemic control, demographic and socio-economic status in patients with Type 1 diabetes under routine clinical care in Brazil. METHODS: This was a cross-sectional, multi-centre study conducted between December 2008 and December 2010 in 28 public clinics in 20 Brazilian cities. The data were obtained from 3176 patients, aged 22 ± 11.8 years, of whom 56.3% were female and 57.4% were Caucasian. The mean time since diabetes diagnosis was 11.7 ± 8.1 years. RESULTS: The prevalence of self-monitoring of blood glucose was 88.5%. There was a significant increase in self-monitoring frequency associated with female gender, lower ages, more intensive diabetes management and higher socio-economic status. A correlation between HbA(1c) levels and the daily frequency of self-monitoring was observed (r(s) = -0.13; P = 0.001). The mean HbA1c levels were related to the daily frequency of self-monitoring (P < 0.001) without additional benefit to patients who performed self-monitoring more than four times daily (9.2, 11.2, 10.2,15.2 and 15% for one, two, three, four, five or more self-monitoring tests daily, respectively; P < 0.0001). CONCLUSIONS: The majority of our patients (88.5%) performed three or more self-monitoring tests daily, with more frequent testing reported by females, younger patients, those on intensive insulin regimens and of higher socio-economic status. No additional benefit was found in patients who performed self-monitoring more than four times daily. The diabetes care team must improve patients' education regarding self-monitoring of blood glucose and its benefits.


Assuntos
Automonitorização da Glicemia , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Hemoglobinas Glicadas/metabolismo , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Adolescente , Adulto , Análise de Variância , Brasil/epidemiologia , Estudos Transversais , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Cooperação do Paciente , Educação de Pacientes como Assunto , Qualidade de Vida , Estudos Retrospectivos , Fatores Socioeconômicos , Fatores de Tempo
9.
Clin Otolaryngol ; 38(6): 487-93, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24148211

RESUMO

OBJECTIVE: This study aimed to evaluate the effect of adenotonsillectomy on visual attention and daytime sleepiness in children with sleep-disordered breathing. DESIGN: This was a controlled prospective cohort study. SETTING: Outpatients from the Otorhinolaryngology Division of Edmundo Vasconcelos Hospital Complex, São Paulo, Brazil. PARTICIPANTS: Patients aged 6-17 years with upper airway obstruction scheduled to undergo adenotonsillectomy (treatment group) in the Otorhinolaryngology Division of Edmundo Vasconcelos Hospital Complex, in São Paulo, Brazil. Participants of control group were consecutively selected from another outpatient clinic of paediatric surgery, but those with symptoms of sleep-disordered breathing were excluded. MAIN OUTCOME MEASURES: Children were submitted to visual attention tests (TAVIS-3) that discriminates normal subjects from those with attentional disorders in advance of the surgery and 2 months later, and in the same period for the control group. Parents were interviewed about lifestyle, sleep characteristics and daytime sleepiness. RESULTS: The analysis included 27 patients in the adenotonsillectomy group and 30 controls, who had similar age (10.0 ± 3.3 versus 10.3 ± 3.7 years; P = 0.8), gender (41% boys versus 57%, respectively) and body mass index. There was marked decrease in daytime sleepiness after surgery (delta between groups: -4.7 ± 3.8; P < 0.001), as well as reductions in reaction time, errors of omission and errors of commission in the treatment compared with the control group at both time points, before and after surgery. CONCLUSIONS: This study shows that adenotonsillectomy in children and adolescents with sleep-disordered breathing reduces daytime sleepiness and improves the performance in tests of visual attention.


Assuntos
Adenoidectomia/métodos , Atenção/fisiologia , Apneia Obstrutiva do Sono/cirurgia , Tonsilectomia/métodos , Percepção Visual/fisiologia , Adolescente , Índice de Massa Corporal , Criança , Feminino , Seguimentos , Humanos , Masculino , Polissonografia , Estudos Prospectivos , Apneia Obstrutiva do Sono/fisiopatologia , Inquéritos e Questionários , Resultado do Tratamento
10.
Braz J Biol ; 83: e274991, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37909589

RESUMO

The objective of this study was to evaluate the water status, photosynthetic pigments, and photochemical efficiency of mini watermelon plants under salt stress and phosphate fertilization. The experiment was conducted in pots under greenhouse conditions in Pombal, PB, Brazil. The experimental design used was randomized blocks in a 5 × 4 factorial scheme, with five levels of electrical conductivity of irrigation water - ECw (0.3, 1.3, 2.3, 3.3, and 4.3 dS m-1) and four doses of phosphorus (60, 80, 100, and 120% of the recommendation), with three replicates. The relative water content in the tissues decreased with the increase in ECw levels in all phosphorus doses, with decreases of 7.05, 7.81 and 8.83% per unit increase in ECw, in plants fertilized with 80, 100 and 120% P2O5. On the other hand, ECw levels increased electrolyte leakage, regardless of phosphorus doses of the recommendation. The synthesis of photosynthetic pigments and the quantum efficiency of photosystem II were inhibited by increasing water salinity from 0.3 dS m-1 in plants grown under phosphorus doses above 60% of the recommendation. Water salinity from 0.3 dS m-1 reduced chlorophyll b contents, initial, maximum, and variable fluorescence of mini watermelon plants, with a decrease of 11.86, 4.51, 4.53, and 4.54% per unit increment of ECw, respectively.


Assuntos
Citrullus , Fosfatos , Fotossíntese , Águas Salinas , Fósforo
11.
Braz J Biol ; 83: e274595, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37792747

RESUMO

The objective of this study was to evaluate the salicylic acid applications in attenuating the harmful effects of saline nutrient solution on the physiology and growth of 'Gaúcho' melon cultivated in the NFT hydroponic system. The experiment was conducted in a greenhouse, in Pombal-PB, Brazil. The cultivation system used was the Nutrient Film Technique - NFT hydroponics. A completely randomized split-plot design was used, with the plot referring to four levels of salinity in the nutrient solution - ECns (2.1 control, 3.2, 4.3, and 5.4 dS m-1) and the sub-plot four concentrations of salicylic acid (SA) (0, 1.5, 3.0, and 4.5 mM), applied via foliar spray, with six replications. Nutrient solution of 4.3 and 5.4 dS m-1 electrical conductivity promotes higher maximum and variable fluorescence, respectively. The stomatal conductance, transpiration, stem diameter, main branch length, leaf dry mass, and stem dry mass of 'Gaúcho' melon plants decrease with the increase in salinity of the nutrient solution. Salicylic acid increases the initial fluorescence and the main branch length of 'Gaúcho' melon plants in hydroponic cultivation. Salicylic acid at a concentration of 1.5 to 4.5 mM did not attenuate the effects of salt stress on the internal CO2 concentration, CO2 assimilation rate, and root dry mass of 'Gaúcho' melon plants.


Assuntos
Dióxido de Carbono , Cucurbitaceae , Hidroponia , Ácido Salicílico/farmacologia , Fluorescência , Estresse Salino , Clorofila
12.
Int J Sports Med ; 33(8): 627-34, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22562730

RESUMO

The aim of the present study was to compare the effects of using different intensities and types of aerobic exercise (i. e., cycle ergometer or running) during concurrent training on neuromuscular adaptations. A total of 44 young women were randomly assigned to 1 of 4 groups: concurrent strength and continuous running training (SCR, n=10), concurrent strength and interval running training (SIR, n=11), concurrent strength and continuous cycle ergometer training (SCE, n=11), or strength training only (STO, n=12). Each group trained twice a week during 11 weeks. The following strength measurements were made on all subjects before and after training period: maximal strength (1RM) in knee extension, bench press and leg press exercises; local muscular endurance (number of repetitions at 70% of 1 RM) in knee extension and bench press exercises; and isometric and isokinetic peak torque of knee extension. There were significant increases in the upper and lower-body 1 RM, isometric and isokinetic peak torque in all training groups (p<0.001), with no differences between groups. The present results suggest that in young women, concurrent training performed twice a week promotes similar neuromuscular adaptations to strength training alone, regardless of the type and the intensity in which the aerobic training is performed.


Assuntos
Adaptação Fisiológica , Ciclismo/fisiologia , Exercício Físico/fisiologia , Resistência Física/fisiologia , Treinamento Resistido/métodos , Corrida/fisiologia , Adulto , Ergometria , Feminino , Humanos , Força Muscular/fisiologia , Adulto Jovem
13.
Nutr Res ; 104: 29-35, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35588611

RESUMO

Cardiovascular diseases (CVDs) represent the leading cause of death in individuals worldwide. Gut microbiota-derived metabolite trimethylamine N-oxide (TMAO) can be metabolized from phosphatidylcholine, choline, and l-carnitine and may play an important role in CVD etiology. Thus, this systematic review aimed to evaluate the effect of probiotics to mitigate TMAO concentrations by gut microbiota modulation. A systematic review was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis protocol from databases: PubMed, Web of Sciences, CENTRAL, and Scopus. Controlled intervention studies published until January 3, 2022, with a population at cardiovascular risk were included. The risk of bias was assessed by RoB 2.0 and SYRCLE's for humans and animals' studies, respectively. The search in the database returned 5389 studies, of which 8 matched all criteria to final qualitative analysis. Four studies were controlled trials with humans (total population = 115) and 4 were animal model studies. The body of evidence on the use of probiotics to reduce TMAO concentrations shows that only a few strains have this beneficial effect. This review can conclude that Lactobacillus rhamnosus GG were the most efficient strains in reducing the plasma TMAO level in both humans and animals. In addition, it is worth mentioning the promising character of Lactobacillus plantarum ZDY04, Lactobacillus amylovorus LAM 1345, Lactiplantibacillus plantarum LP1145, and Enterobacter aerogenes ZDY01 for having had the same effect in animals.


Assuntos
Doenças Cardiovasculares , Microbioma Gastrointestinal , Probióticos , Animais , Doenças Cardiovasculares/etiologia , Colina/metabolismo , Humanos , Metilaminas
14.
Genet Mol Res ; 10(3): 2172-80, 2011 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-21968724

RESUMO

Genetic diversity analyses of tropical tree species are relevant to landscape management, plant genetic resource inventory, and biological conservation of threatened species. Annona crassiflora is an endangered fruit tree native to the Cerrado biome that is threatened by reduction of natural populations and fruit extraction. We examined the intra- and interpopulational genetic diversity of this species in the northern region of Minas Gerais State. Seventy-two individuals from four natural populations were genotyped using RAPD markers. We found moderate genetic diversity among populations, with Shannon's I index varying between 0.31 and 0.44, and Nei's genetic diversity (H(E)) for the population set equal to 0.31. AMOVA indicated a greater genetic variation within (77.38%) rather than among populations (22.62%), tending towards isolation by distance (Mantel's r = 0.914; P = 0.089). Nei's genetic identity estimates among populations revealed a hierarchical pattern of genetic similarity of form [(CA1, CA2), MC], [(GM)], corroborating the high genetic differentiation between spatially isolated populations.


Assuntos
Annona/genética , Variação Genética , Brasil , Marcadores Genéticos , Genótipo , Filogenia , Polimorfismo Genético , Técnica de Amplificação ao Acaso de DNA Polimórfico
15.
J Mech Behav Biomed Mater ; 117: 104378, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33610021

RESUMO

Polymeric scaffolds provide several advantages when compared with other bone replacement and regenerating techniques. Namely, when compared with the current gold standard, bone autografts, there is no shortage of supply nor donor site morbidity. Contrarily to metallic implants, their mechanical properties are similar to those of cortical bone and they are biodegradable, therefore stress shielding is not expected to occur, and they will be gradually replaced by new bone tissue. Yet, there are still several challenges to overcome. After implantation scaffolds are subjected to dynamic loads, thus understanding polymeric scaffolds' fatigue behavior plays a major role on the design of better products. In this work PLA scaffolds were manufactured using 3D printing with optimized parameters. A total of six configurations were tested under static and dynamic load conditions. Static compression testing and numerical simulation showed good correlation. Numerical simulation provided a viable resource for scaffold design and innovation. Four different low-cycle fatigue loads were applied, during 3600 cycles with a frequency of 0.25 Hz. While under dynamic conditions, with a maximum stress of 24 MPa and R = 0.1, the apparent compressive modulus reached 973 MPa, due to pore collapse. Even after 3600 cycles no significant fatigue damage mechanisms were found on low porosity scaffolds, rendering them useful for trabecular bone replacement under dynamic conditions.


Assuntos
Osso Esponjoso , Alicerces Teciduais , Força Compressiva , Teste de Materiais , Porosidade , Impressão Tridimensional , Engenharia Tecidual
16.
Mater Sci Eng C Mater Biol Appl ; 118: 111528, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33255081

RESUMO

Bone transplant is still the gold standard approach when dealing with orthopedic trauma or disease. When this solution is not possible, scaffolding is a possibility provided by bone tissue engineering. To support the regeneration process, damaged bone tissue is removed and replaced by porous scaffold structures. In recent years, additive manufacturing has shown huge potential to produce scaffold structures with the required performance. In the current work, PLA scaffolds with different designs were 3D printed, using optimal manufacturing parameters. Scaffolds with three different porosity values were obtained by changing the filament offset from 571 to 1333 µm. A total of twelve designs were tested under monotonic and dynamic compression conditions. Numerical analysis showed good correlation with experimental results, allowing for a better assessment of scaffold mechanical behavior. Stress relaxation was measured on four different strain levels, assessing scaffold's behavior after implantation and consequent static response over time. Overall, orthogonal design provided better performance, due to improved material deposition. With lower porosity scaffolds equilibrium stress reached 24 MPa after 300 s relaxation time under 4% deformation, and the obtained equilibrium modulus was 428 MPa. Overall, attained results show that 3D printing with PLA can be applied in the manufacture of scaffolds for trabecular bone replacement.


Assuntos
Osso Esponjoso , Alicerces Teciduais , Poliésteres , Porosidade , Impressão Tridimensional , Engenharia Tecidual
17.
Theriogenology ; 174: 124-130, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34428678

RESUMO

The aim of this study was to evaluate the effect of 1 µmol/L zearalenone (ZEN) and 1 µmol/L enterolactone (ENL), alone or in combination, on the survival and morphology of in vitro cultured ovarian preantral follicles. Ovaries from 10 sheep were collected at a local abattoir and fragmented, and the ovarian pieces were submitted to in vitro culture for 3 days in the presence or absence of the test compounds. The morphology of primordial and primary follicles was impaired by ZEN, whereas that of cultured secondary follicles was improved by ENL. However, the combination of ENL with ZEN impaired the quality of primary and secondary follicles. Both ZEN and ENL induced apoptosis, but only ZEN was responsible for oocyte autophagy. None of these xenoestrogens affected endoplasmic reticulum stress as observed by the unaltered expression of ERP29. Differently from ZEN, ENL increased the expression of the efflux transporter ABCG2. In conclusion, although ENL can counteract the negative effects of ZEN on primordial and primary follicles, this positive effect is not similar to that observed in ovarian tissue cultures in the presence of ENL alone.


Assuntos
Zearalenona , 4-Butirolactona/análogos & derivados , Animais , Feminino , Lignanas , Oócitos , Folículo Ovariano , Ovário , Ovinos , Zearalenona/toxicidade
18.
Trop Biomed ; 37(3): 763-777, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33612789

RESUMO

The aim of this study was to evaluate the prevalence of enteroparasitic infections in students and their hormonal and immunological repercussions on physical development. Students of basic education of both sexes were evaluated. Parasitological stool tests were performed using the Hoffman and Kato-Katz methods. The students were divided into two groups: a control group (negative parasitological examination, N=25) and an infected group (positive parasitological test, N=25). Anthropometric variables (height, weight, and BMI), concentrations of hormones (melatonin and cortisol), cytokine/chemokine levels (IL-1ß, IL-6, IL-8, IL-10, IL-12, IL-17 and TNF-α) and physical performance (aerobic capacity, upper- and lower-limb muscle strength and abdominal performance) were evaluated. The prevalence of parasitic infection among the students was 7.98%. No anthropometric differences were observed among the groups. IL-2 and TNF-α levels were higher and IL-8 levels were lower in serum from students who were positive for parasitic infection. Serum from students who were positive for parasitic infection showed higher levels of melatonin than that from parasitenegative students. No differences were observed in cortisol levels. Students who were positive for parasitic infection presented greater lower-limb strength and lower abdominal performance than parasite-negative students. In the parasitic infection group, IL-12 was positively correlated with melatonin. In the parasitic infection group, IL-8 showed a positive correlation with aerobic capacity, while IL-17 and TNF-α showed a positive correlation with abdominal performance. These data suggest that parasitic infections determine the profile of inflammatory cytokines and that melatonin may be involved in the control of this process to minimize tissue damage. Additionally, students' difficulty in practising physical exercises can be an indication of enteroparasitic infection.


Assuntos
Enteropatias Parasitárias/fisiopatologia , Aptidão Física , Adolescente , Brasil/epidemiologia , Criança , Pré-Escolar , Citocinas/sangue , Feminino , Humanos , Hidrocortisona/sangue , Enteropatias Parasitárias/epidemiologia , Masculino , Melatonina/sangue , Prevalência , Estudantes
19.
Braz J Med Biol Res ; 53(6): e9031, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32401929

RESUMO

Malnutrition is still considered endemic in many developing countries. Malnutrition-enteric infections may cause lasting deleterious effects on lipid metabolism, especially in children living in poor settings. The regional basic diet (RBD), produced to mimic the Brazilian northeastern dietary characteristics (rich in carbohydrate and low in protein) has been used in experimental malnutrition models, but few studies have explored the effect of chronic RBD on liver function, a central organ involved in cholesterol metabolism. This study aimed to investigate whether RBD leads to liver inflammatory changes and altered reverse cholesterol metabolism in C57BL6/J mice compared to the control group, receiving a standard chow diet. To evaluate liver inflammation, ionized calcium-binding adapter protein-1 (IBA-1) positive cell counting, interleukin (IL)-1ß immunohistochemistry, and tumor necrosis factor (TNF)-α and IL-10 transcription levels were analyzed. In addition, we assessed reverse cholesterol transport by measuring liver apolipoprotein (Apo)E, ApoA-I, and lecithin-cholesterol acyltransferase (LCAT) by RT-PCR. Furthermore, serum alanine aminotransferase (ALT) was measured to assess liver function. RBD markedly impaired body weight gain compared with the control group (P<0.05). Higher hepatic TNF-α (P<0.0001) and IL-10 (P=0.001) mRNA levels were found in RBD-challenged mice, although without detectable non-alcoholic fatty liver disease. Marked IBA-1 immunolabeling and increased number of positive-IBA-1 cells were found in the undernourished group. No statistical difference in serum ALT was found. There was also a significant increase in ApoA mRNA expression in the undernourished group, but not ApoE and LCAT, compared with the control. Altogether our findings suggested that chronic RBD-induced malnutrition leads to liver inflammation with increased ApoA-I activity.


Assuntos
Apolipoproteína A-I/sangue , Dieta/efeitos adversos , Inflamação/metabolismo , Desnutrição/metabolismo , Animais , Apolipoproteína A-I/metabolismo , Brasil , Doença Crônica , Humanos , Inflamação/sangue , Inflamação/patologia , Fígado/metabolismo , Masculino , Desnutrição/sangue , Desnutrição/patologia , Camundongos , Camundongos Endogâmicos C57BL
20.
Int Immunopharmacol ; 73: 293-303, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31128529

RESUMO

Egg yolk constitutes a relevant alternative source of antibodies. It presents some advantages over mammalian serum immunoglobulins regarding productivity, animal welfare and specificity. The main immunoglobulin present in avian blood (IgY) is transmitted to their offspring and accumulates in egg yolks, which enables the non-invasive harvesting of high amounts of antibodies. Moreover, due to structural differences and phylogenetic distance, IgY is more suitable for diagnostic purposes than mammalian antibodies, since it does not react with certain components of the human immune system and displays greater avidity for mammalian conserved proteins. IgY has been extensively used in health researches, as both therapeutic and diagnostic tool. This article aims to review its applications in both human and veterinary health.


Assuntos
Gema de Ovo/imunologia , Imunoglobulinas/uso terapêutico , Animais , Bioterrorismo , Conservação de Alimentos , Humanos , Imunoglobulinas/química , Imunoglobulinas/imunologia , Infecções/diagnóstico , Infecções/imunologia , Neoplasias/diagnóstico , Neoplasias/imunologia
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