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1.
Materials (Basel) ; 13(11)2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32503200

RESUMO

In the name of the authors of the paper "Permeability versus Design in TPMS Scaffolds", published in Materials in 2019 and already counting six citations in Google Scholar to date, I would like to formally respond to the comment manuscript now entitled "Assessing Porous Media Permeability in Non-Darcy Flow: A Re-Evaluation Based on the Forchheimer Equation" [...].

2.
Materials (Basel) ; 12(8)2019 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-31013656

RESUMO

Scaffolds for bone tissue engineering are porous structures that serve as support for cellular growth and, therefore, new tissue formation. The present work assessed the influence of the porous architecture of triply periodic minimal surface (TPMS) scaffolds on their macroscopic permeability behavior, combining numerical and experimental methods. The TPMS scaffolds considered were Schwartz D, Schwartz P, and Gyroid, which have been previously studied for bone tissue engineering, with 70% porosity. On the experimental side, these scaffolds were produced by MultiJet 3D printing and tested for fluid passage to calculate their permeability through Darcy's Law. On the numerical side, finite element (FE) models of the scaffolds were simulated on ABAQUS® for fluid passage under compression to assess potential fluid concentration spots. The outcomes revealed that the design of the unit cell had a noticeable effect on both calculated permeability and FE computed fluid flow velocity, regardless of the identical porosity, with the Gyroid scaffold having higher permeability and the Schwartz P a lower probability of fluid trapping. Schwartz D had the worst outcomes in both testing modalities, so these scaffolds would most likely be the last choice for promoting cell differentiation onto bone cells. Gyroid and Schwartz P would be up for selection depending on the application and targeted bone tissue.

3.
Genet Mol Res ; 15(4)2016 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-27813580

RESUMO

Macaw palm (Acrocomia aculeata) is a promising species for use in biofuel production, and establishing breeding programs is important for the development of commercial plantations. The aim of the present study was to analyze genetic diversity, verify correlations between traits, estimate genetic parameters, and select different accessions of A. aculeata in the Macaw Palm Germplasm Bank located in Universidade Federal de Viçosa, to develop a breeding program for this species. Accessions were selected based on precocity (PREC), total spathe (TS), diameter at breast height (DBH), height of the first spathe (HFS), and canopy area (CA). The traits were evaluated in 52 accessions during the 2012/2013 season and analyzed by restricted estimation maximum likelihood/best linear unbiased predictor procedures. Genetic diversity resulted in the formation of four groups by Tocher's clustering method. The correlation analysis showed it was possible to have indirect and early selection for the traits PREC and DBH. Estimated genetic parameters strengthened the genetic variability verified by cluster analysis. Narrow-sense heritability was classified as moderate (PREC, TS, and CA) to high (HFS and DBH), resulting in strong genetic control of the traits and success in obtaining genetic gains by selection. Accuracy values were classified as moderate (PREC and CA) to high (TS, HFS, and DBH), reinforcing the success of the selection process. Selection of accessions for PREC, TS, and HFS by the rank-average method permits selection gains of over 100%, emphasizing the successful use of the accessions in breeding programs and obtaining superior genotypes for commercial plantations.


Assuntos
Arecaceae/genética , Arecaceae/fisiologia , Cruzamento , Ecótipo , Variação Genética , Análise por Conglomerados , Análise de Componente Principal , Característica Quantitativa Herdável , Reprodução/genética , Seleção Genética
4.
Hum Exp Toxicol ; 35(9): 958-65, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26500220

RESUMO

Vigabatrin (VGB) is an antiepileptic drug thatincreases brain γ-aminobutyric acid (GABA) levels through irreversible inhibition of GABA transaminase. The aim of this study was to evaluate neurotoxicological effects of VGB measuring motor activity and genotoxic and mutagenic effects after a single and repeated administration. Male Wistar rats received saline, VGB 50, 100, or 250 mg/kg by gavage for acute and subchronic (14 days) treatments and evaluated in the rotarod task. Genotoxicity was evaluated using the alkaline version of the comet assay in samples of blood, liver, hippocampus, and brain cortex after both treatments. Mutagenicity was evaluated using the micronucleus test in bone marrow of the same animals that received subchronic treatment. The groups treated with VGB showed similar performance in rotarod compared with the saline group. Regarding the acute treatment, it was observed that only higher VGB doses induced DNA damage in blood and hippocampus. After the subchronic treatment, VGB did not show genotoxic or mutagenic effects. In brief, VGB did not impair motor activities in rats after acute and subchronic treatments. It showed a repairable genotoxic potential in the central nervous system since genotoxicity was observed in the acute treatment group.


Assuntos
4-Aminobutirato Transaminase/antagonistas & inibidores , Anticonvulsivantes/toxicidade , Dano ao DNA , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Vigabatrina/toxicidade , Animais , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/enzimologia , Córtex Cerebral/patologia , Ensaio Cometa , Relação Dose-Resposta a Droga , Hipocampo/efeitos dos fármacos , Hipocampo/enzimologia , Hipocampo/patologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Masculino , Testes para Micronúcleos , Atividade Motora/efeitos dos fármacos , Especificidade de Órgãos , Ratos Wistar , Teste de Desempenho do Rota-Rod , Fatores de Tempo
5.
Environ Pollut ; 206: 236-46, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26196313

RESUMO

Mercury (Hg) is a highly toxic pollutant that poses in risk several marine animals, including green turtles (Chelonia mydas). Green turtles are globally endangered sea turtle species that occurs in Brazilian coastal waters as a number of life stage classes (i.e., foraging juveniles and nesting adults). We assessed total Hg concentrations and isotopic signatures ((13)C and (15)N) in muscle, kidney, liver and scute of juvenile green turtles and their food items from two foraging grounds with different urban and industrial development. We found similar food preferences in specimens from both areas but variable Hg levels in tissues reflecting the influence of local Hg backgrounds in food items. Some juvenile green turtles from the highly industrialized foraging ground presented liver Hg levels among the highest ever reported for this species. Our results suggest that juvenile foraging green turtles are exposed to Hg burdens from locally anthropogenic activities in coastal areas.


Assuntos
Monitoramento Ambiental/métodos , Preferências Alimentares , Mercúrio/análise , Tartarugas/metabolismo , Poluentes Químicos da Água/análise , Animais , Brasil , Isótopos de Carbono/análise , Rim/química , Fígado/química , Mercúrio/farmacocinética , Isótopos de Nitrogênio/análise , Distribuição Tecidual , Tartarugas/crescimento & desenvolvimento , Poluentes Químicos da Água/farmacocinética
6.
J Parasitol ; 101(4): 500-3, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25738321

RESUMO

The helminth fauna of 31 juvenile specimens of Eretmochelys imbricata from the Brazilian coast was examined. Seventeen individuals were infected with helminths (54.8%). The helminths found were: Diaschistorchis pandus, Cricocephalus albus, Metacetabulum invaginatum, Pronocephalus obliquus (Pronocephalidae), Cymatocarpus solearis (Brachycoeliidae), Styphlotrema solitaria (Styphlotrematidae), Carettacola stunkardi, Amphiorchis caborojoensis (Spirorchiidae), Orchidasma amphiorchis (Telorchiidae), and Anisakis nematode larvae. This report is the first analysis of parasite communities in this host.


Assuntos
Helmintíase Animal/parasitologia , Tartarugas/parasitologia , Animais , Brasil/epidemiologia , Feminino , Helmintíase Animal/epidemiologia , Masculino , Prevalência
7.
Dis Aquat Organ ; 111(3): 207-17, 2014 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-25320033

RESUMO

Fibropapillomatosis (FP) is a benign neoplasia that affects physiological functions of sea turtles and may lead to death. High prevalence of FP in sea turtle populations has prompted several research groups to study the disease and the associated herpesvirus, chelonid herpesvirus 5 (ChHV5). The present study detected and quantified ChHV5 in 153 fibropapilloma samples collected from green turtles Chelonia mydas on the Brazilian coast between 2009 and 2010 to characterize the relationship between viral load and tumor characteristics. Of the tumor samples collected, 73 and 87% were positive for ChHV5 in conventional PCR and real-time PCR, respectively, and viral loads ranged between 1 and 118.62 copies cell⁻¹. Thirty-three percent of turtles were mildly, 28% were moderately and 39% were severely affected with FP. Skin samples were used as negative control. High viral loads correlated positively with increasing FP severity in turtles sampled on the Brazilian coast and with samples from turtles found dead in the states of São Paulo and Bahia. Six viral variants were detected in tumor samples, 4 of which were similar to the Atlantic phylogenetic group. Two variants were similar to the western Atlantic/eastern Caribbean phylogenetic group. Co-infection in turtles with more than one variant was observed in the states of São Paulo and Bahia.


Assuntos
Infecções por Herpesviridae/veterinária , Herpesviridae/isolamento & purificação , Papiloma/veterinária , Neoplasias Cutâneas/veterinária , Infecções Tumorais por Vírus/veterinária , Tartarugas , Animais , Brasil/epidemiologia , DNA Viral/análise , Feminino , Herpesviridae/genética , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/virologia , Masculino , Papiloma/epidemiologia , Papiloma/virologia , Filogenia , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/virologia , Infecções Tumorais por Vírus/epidemiologia , Infecções Tumorais por Vírus/virologia
8.
Sci Total Environ ; 435-436: 402-10, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22878100

RESUMO

Contamination of waters by xenobiotic compounds such as pesticides presents a serious environmental problem with substantial levels of pesticides now contaminating European water resources. The aim of this work was to evaluate the ability of the fungi Fusarium oxysporum, Aspergillus oryzae, Lentinula edodes, Penicillium brevicompactum and Lecanicillium saksenae, for the biodegradation of the pesticides terbuthylazine, difenoconazole and pendimethalin in batch liquid cultures. These pesticides are common soil and water contaminants and terbuthylazine is considered the most persistent triazine herbicide in surface environments. P. brevicompactum and L. saksenae were achieved by enrichment, isolation and screening of fungi capable to metabolize the pesticides studied. The isolates were obtained from two pesticide-primed materials (soil and biomixture). Despite the relatively high persistence of terbuthylazine, the results obtained in this work showed that the fungi species studied have a high capability of biotransformation of this xenobiotic, comparatively the results obtained in other similar studies. The highest removal percentage of terbuthylazine from liquid medium was achieved with A. oryzae (~80%), although the major biodegradation has been reached with P. brevicompactum. The higher ability of P. brevicompactum to metabolize terbuthylazine was presumably acquired through chronic exposure to contamination with the herbicide. L. saksenae could remove 99.5% of the available pendimethalin in batch liquid cultures. L. edodes proved to be a fungus with a high potential for biodegradation of pesticides, especially difenoconazole and pendimethalin. Furthermore, the metabolite desethyl-terbuthylazine was detected in L. edodes liquid culture medium, indicating terbuthylazine biodegradation by this fungus. The fungi strains investigated could prove to be valuable as active pesticide-degrading microorganisms, increasing the efficiency of biopurification systems containing wastewaters contaminated with the xenobiotics studied or compounds with similar intrinsic characteristics.


Assuntos
Compostos de Anilina/metabolismo , Dioxolanos/metabolismo , Fungos/metabolismo , Resíduos de Praguicidas/metabolismo , Triazinas/metabolismo , Triazóis/metabolismo , Biodegradação Ambiental , Poluentes do Solo/metabolismo , Poluentes Químicos da Água/metabolismo
9.
Proc Natl Acad Sci U S A ; 104(47): 18555-60, 2007 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-18003934

RESUMO

Biodiversity loss from deforestation may be partly offset by the expansion of secondary forests and plantation forestry in the tropics. However, our current knowledge of the value of these habitats for biodiversity conservation is limited to very few taxa, and many studies are severely confounded by methodological shortcomings. We examined the conservation value of tropical primary, secondary, and plantation forests for 15 taxonomic groups using a robust and replicated sample design that minimized edge effects. Different taxa varied markedly in their response to patterns of land use in terms of species richness and the percentage of species restricted to primary forest (varying from 5% to 57%), yet almost all between-forest comparisons showed marked differences in community structure and composition. Cross-taxon congruence in response patterns was very weak when evaluated using abundance or species richness data, but much stronger when using metrics based upon community similarity. Our results show that, whereas the biodiversity indicator group concept may hold some validity for several taxa that are frequently sampled (such as birds and fruit-feeding butterflies), it fails for those exhibiting highly idiosyncratic responses to tropical land-use change (including highly vagile species groups such as bats and orchid bees), highlighting the problems associated with quantifying the biodiversity value of anthropogenic habitats. Finally, although we show that areas of native regeneration and exotic tree plantations can provide complementary conservation services, we also provide clear empirical evidence demonstrating the irreplaceable value of primary forests.


Assuntos
Biodiversidade , Agricultura Florestal , Clima Tropical
11.
Oecologia ; 122(3): 410-420, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28308292

RESUMO

We examined standard niche axes (time, place, and food) for three sympatric teiid lizards in the Amazon rain forest. Activity times during the day were similar among species. Ameiva ameiva were in more open microhabitats and had higher body temperatures compared with the two species of Kentropyx. Microhabitat overlaps were low and not significantly different from simulations based on Monte Carlo analysis. Grasshoppers, crickets, and spiders were important in the diets of all three species and many relatively abundant prey were infrequently eaten (e.g., ants). Dietary overlaps were most similar between the two species of Kentropyx even though microhabitat overlaps were relatively low. A Monte Carlo analysis on prey types revealed that dietary overlaps were higher at all ranks than simulated overlaps indicating that use of prey is not random. Although prey size was correlated with lizard body size, there were no species differences in adjusted prey size. A. ameiva ate more prey items at a given body size than either species of Kentropyx. Body size varies among species, with A. ameiva being the largest and K. altamazonica the smallest. The two species of Kentropyx are most distant morphologically, with A. ameiva intermediate. The most distant species morphologically are the most similar in terms of prey types. A morphological analysis including 15 species from four genera revealed patterns of covariation that reflected phylogenetic affinities (i.e., taxonomic patterns are evident). A cluster analysis revealed that A. ameiva, K. pelviceps, and K. altamazonica were in the same morphological group and that within that group, A. ameiva differed from the rest of the species. In addition, K. pelviceps and K. altamazonica were distinguishable from other species of Kentropyx based on morphology.

13.
Rev. ginecol. obstet ; 1(4): 282-8, out. 1990. ilus, tab
Artigo em Português | LILACS | ID: lil-154430

RESUMO

Foram examinados 60 parceiros sexuais, de mulheres diagnosticadas como portadoras de infeccao genital pelo papilomavirus, sob protocolo de investigacao. O objetivo era identificar colposcopicamente, lesoes acetobrancas na genitalia externa masculina, biopsia-las e estuda-las histopatologicamente. Predominava como sinal patognomonico, a coilocitose celular. A biopsia foi positiva em 77,1 por cento e negativa em 22,9 por cento. Os resultados da pesquisa fecham a hipotese de que o parceiro sexual masculino e, de fato, um elemento de risco, agindo como transmissor de infeccao genital pelo papilomavirus humano.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Genitália Masculina/patologia , Infecções Tumorais por Vírus/transmissão , Papillomaviridae , Colposcopia , Parceiros Sexuais
14.
Rev. bras. ginecol. obstet ; 3(3): 115-9, 1981.
Artigo em Português | LILACS | ID: lil-4445

RESUMO

Em 19 maternidades da cidade do Recife (Pernambuco, Brasil), em 1979, houve um total de 12 156 cesarianas (incidencia de 28,1%) e 30 953 partos vaginais. A mortalidade materna na operacao cesariana, foi de 3,3 por 1 000.Nas pacientes indigentes, foram realizadas 2 327 cesarianas (incidencia de 11,2%) e 18 414 partos vaginais. A mortalidade materna na operacao cesariana foi de 9 por 1 000. Nas pacientes do INAMPS, foram realizadas 5621 cesarianas (incidencia de 35,4%) e 10226 partos vaginais. A mortalidade materna na operacao cesariana foi de 3 por 1000. Nas pacientes previdenciarias estaduais e militares, foram realizadas 444 cesarianas (incidencia de 42,6%) e 596 partos vaginais. A mortalidade materna na operacao cesariana foi de 2,2 por 1 000. Nas pacientes de clinica particular, foram realizadas 3 764 cesarianas (incidencia de 67,7%) e 1 717 partos vaginais A mortalidade materna na operacao cesariana foi de 0,5 por 1 000. As causas mais frequentes de mortalidade materna foram: hemorragia, eclampsia, infeccao e embolia amniotica. No global, a mortalidade materna na operacao cesariana foi 6,13 vezes maior do que no parto vaginal


Assuntos
Cesárea , Mortalidade Materna , Brasil
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