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1.
Pharmaceuticals (Basel) ; 17(6)2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38931388

RESUMO

Melanoma, primarily caused by solar ultraviolet (UV) radiation, can be prevented by the use of sunscreens. However, the use of synthetic sunscreens raises environmental concerns. Natural compounds with antioxidant photoprotective properties and cytotoxic effects against cancer cells can be promising for the prevention and treatment of melanoma with less environmental effect. This study focuses on Melaleuca leucadendron essential oil (EO) for photoprotection and antitumor applications. EO was hydrodistilled from M. leucadendron leaves with a 0.59% yield. Gas chromatography-mass spectrometry detected monoterpenes and sesquiterpenes. Nanoemulsions were prepared with (NE-EO) and without EO (NE-B) using the phase inversion method, showing good stability, spherical or oval morphology, and a pseudoplastic profile. Photoprotective activity assessed spectrophotometrically showed that the NE-EO was more effective than NE-B and free EO. Antioxidant activity evaluated by DPPH and ABTS methods indicated that pure and nanoemulsified EO mainly inhibited the ABTS radical, showing IC50 40.72 and 5.30 µg/mL, respectively. Cytotoxicity tests on L-929 mouse fibroblasts, NGM human melanocyte, B16-F10 melanoma, and MeWo human melanoma revealed that EO and NE-EO were more cytotoxic to melanoma cells than to non-tumor cells. The stable NE-EO demonstrates potential for melanoma prevention and treatment. Further research is required to gain a better understanding of these activities.

2.
Environ Sci Pollut Res Int ; 30(54): 115646-115665, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37884715

RESUMO

Manganese (Mn) is one of the essential mineral micronutrients most demanded by cacao. Cadmium (Cd) is highly toxic to plants and other living beings. There are indications that Mn can interact with Cd and mitigate its toxicity. The objective of this study was to evaluate the action of Mn on the toxic effect of Cd in young plants of the CCN 51 cacao genotype, subjected to different doses of Mn, Cd, and Mn+Cd in soil, through physiological, biochemical, molecular, and micromorphological and ultrastructural changes. High soil Mn doses favored the maintenance and performance of adequate photosynthetic processes in cacao. However, high doses of Cd and Mn+Cd in soil promoted damage to photosynthesis, alterations in oxidative metabolism, and the uptake, transport, and accumulation of Cd in roots and leaves. In addition, high Cd concentrations in roots and leaf tissues caused irreversible damage to the cell ultrastructure, compromising cell function and leading to programmed cell death. However, there was a mitigation of Cd toxicity when cacao was grown in soils with low Cd doses and in the presence of Mn. Thus, damage to the root and leaf tissues of cacao caused by Cd uptake from contaminated soils can be attenuated or mitigated by the presence of high Mn doses in soil.


Assuntos
Cacau , Poluentes do Solo , Manganês/metabolismo , Cádmio/metabolismo , Solo/química , Antioxidantes/metabolismo , Cacau/química , Fotossíntese , Expressão Gênica , Poluentes do Solo/análise
3.
Neotrop Entomol ; 52(5): 860-874, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37341900

RESUMO

Lasiocampidae belongs to superfamily Lasiocampoidea and contains more than a thousand species nearly distributed worldwide. Despite the great species richness and wide distribution, this group has internal phylogenetic relationships still little explored and with few studies on the morphology and biology of its immatures. This study describes the immature stages of the neotropical species Tolype medialis (Jones, 1912), focusing on the morphology and natural history. The eggs of T. medialis are oviposited freely inside a conical structure, and the larvae showed gregarious behavior in all instars. The seventh and eighth instar bear a pair of abdominal rounded flattened reddish brown glands on the segments A1, A2, A7, and A8 that produce a wax-like secretion that covers the pupae and the internal walls of the cocoon. In order to add information to the Lasiocampidae family, we compare and discuss these and other traits from the morphology and natural history of T. medialis immatures.


Assuntos
Lepidópteros , Animais , Filogenia , Larva/anatomia & histologia , Pupa/anatomia & histologia
4.
Adv Rheumatol ; 63(1): 1, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36597166

RESUMO

BACKGROUND: Fibroblast-like synoviocytes (FLS) play a prominent role in rheumatoid synovitis and degradation of the extracellular matrix through the production of inflammatory cytokines and metalloproteinases (MMPs). Since animal models are frequently used for elucidating the disease mechanism and therapeutic development, it is relevant to study the ultrastructural characteristics and functional responses in human and mouse FLS. The objective of the study was to analyze ultrastructural characteristics, Interleukin-6 (IL-6) and Metalloproteinase-3 (MMP-3) production and the activation of intracellular pathways in Fibroblast like synoviocytes (FLS) cultures obtained from patients with rheumatoid arthritis (RA) and from mice with collagen-induced arthritis (CIA). METHODS: FLSs were obtained from RA patients (RA-FLSs) (n = 8) and mice with CIA (CIA-FLSs) (n = 4). Morphology was assessed by transmission and scanning electron microscopy. IL-6 and MMP-3 production was measured by ELISA, and activation of intracellular signaling pathways (NF-κB and MAPK: p-ERK1/2, p-P38 and p-JNK) was measured by Western blotting in cultures of RA-FLSs and CIA-FLSs stimulated with tumor necrosis factor-alpha (TNF-α) and IL-1ß. RESULTS: RA-FLS and CIA-FLS cultures exhibited rich cytoplasm, rough endoplasmic reticula and prominent and well-developed Golgi complexes. Transmission electron microscopy demonstrated the presence of lamellar bodies, which are cytoplasmic structures related to surfactant production, in FLSs from both sources. Increased levels of pinocytosis and numbers of pinocytotic vesicles were observed in RA-FLSs (p < 0.05). Basal production of MMP-3 and IL-6 was present in RA-FLSs and CIA-FLSs. Regarding the production of MMP-3 and IL-6 and the activation of signaling pathways, the present study demonstrated a lower response to IL-1ß by CIA-FLSs than by RA-FLSs. CONCLUSION: This study provides a comprehensive understanding of the biology of RA-FLS and CIA-FLS. The differences and similarities in ultrastructural morphology and important inflammatory cytokines shown, contribute to future in vitro studies using RA-FLS and CIA-FLS, in addition, they indicate that the adoption of CIA-FLS for studies should take careful and be well designed, since they do not completely resemble human diseases.


Assuntos
Artrite Experimental , Artrite Reumatoide , Sinoviócitos , Humanos , Animais , Camundongos , Sinoviócitos/patologia , Interleucina-6/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Citocinas , Fibroblastos/metabolismo
5.
Natal; s.n; 2023. 38 p. tab, ilus.
Tese em Português | BBO - Odontologia | ID: biblio-1437715

RESUMO

Introdução: O aumento da exigência estética pelos pacientes e o contínuo desenvolvimento de materiais - tais como resinas bulk fill de alta e baixa viscosidade e flow, demanda uma crescente necessidade de estudos nesta área para avaliar as propriedades dos materiais quando submetidos ao desgaste ocasionado pela escovação dentária ao longo do tempo. Objetivo: Avaliar as características superficiais de restaurações antes e após o processo de escovação simulada e comparar os resultados entre os mesmos. Materiais e métodos: Foram confeccionados ao total 80 corpos de prova (7x4mm), sendo 20 para cada tipo de resina utilizada, na cor A1: Bulk Fill One (3M/ESPE, St. Paul, MN, USA), Bulk Fill Flow (3M/ESPE, St. Paul, MN, USA), Z350XT (3M/ESPE St. Paul, MN, USA) e Z350XT Flow (3M/ESPE, St. Paul, MN, USA). Após a confecção, os corpos de prova permaneceram por 24 horas imersos em água destilada em estufa a 37°C, momento no qual foi realizado o acabamento e polimento com a sequência de discos de lixa Praxis (TDV, Brasil). Metade dos corpos de prova foi submetida a 60,000 ciclos de escovação simulada, enquanto a outra metade foi o grupo controle (n=10). A superfície das restaurações foi avaliada por meio do Microscópio Eletrônico de Varredura (MEV), rugosidade superficial (Ra) e variação de massa (através de pesagem) das restaurações antes e após o processo de escovação simulada. Para análise estatística, foi utilizada a análise de variância ANOVA dois fatores e pós teste de Tukey. Resultados: Na análise feita pelo MEV, em amplificação de 500x, foi observada a protuberância de partículas médias e pequenas em todas as resinas após a escovação simulada, com exceção da resina de tipo Z350 flow. Todos os materiais apresentaram aumento da Ra após a escovação simulada. Com relação a variação de massa, não houve diferença estatisticamente significativa. Conclusão: O processo abrasivo ocasionado pela escovação leva a mudanças na disposição das partículas, o que ocasiona mudanças na superfície do material e aumento na rugosidade. Por outro lado, não foi demonstrada diferença com relação a variação de massa (AU).


Introduction: The increasing of the aesthetic exigency by the patients and the continual development of materials ­ such as bulk fill and flow composites, demands a crescent need of studies on this area to evaluate the properties of the materials when submitted to the wear occasioned by toothbrushing abrasion over time. Objective: To evaluate the surface characteristics of restorations performed before and after the process of simulated toothbrushing and to compare the results between the composites. Materials and methods: In total, 80 samples were made (7x4mm), being 20 to each type of resin utilized, color A1: Bulk Fill One (3M/ESPE, St. Paul, MN, USA), Bulk Fill Flow (3M/ESPE, St. Paul, MN, USA), Z350XT (3M/ESPE St. Paul, MN, USA) and Z350XT Flow (3M/ESPE, St. Paul, MN, USA). After the confection of the specimens, the samples were immersed in distilled water for 24 hours and stored at 37°C in stove, moment that was performed the finishing and polishing with the sequence of sandpaper discs (TDV, Brasil). Half of the specimens was submitted to 60,000 cycles of simulated toothbrushing, meanwhile the other half was the control group (n=10). The surface of the restorations was evaluated through Scanning Electronic Microscopy (SEM), surface roughness (Ra), and weight loss (through measurements), in two moments: before and after the process of simulated toothbrushing. To the statistical analysis, it was used the variance analysis ANOVA two factors and Tukey's post test. Results: In the analysis performed by SEM, in amplification of 500x, it was observed the presence of medium and small protruding particles in all resins tested after simulated toothbrushing, with exception of the resin Z350 flow. All materials presented increasing on Ra after simulated toothbrushing. Regarding to mass variation, there was not any significant statistical difference. Conclusion: The abrasive process occasioned by toothbrushing leads to changes on the particles disposition, which causes changes on the surface and increase on the roughness. On the other hand, there was not any difference regarding to mass variation (AU).


Assuntos
Propriedades de Superfície , Microscopia Eletrônica de Varredura/instrumentação , Resinas Compostas/química , Desgaste dos Dentes , Análise de Variância
6.
Adv Rheumatol ; 63: 1, 2023. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1447155

RESUMO

Abstract Background Fibroblast-like synoviocytes (FLS) play a prominent role in rheumatoid synovitis and degradation of the extracellular matrix through the production of inflammatory cytokines and metalloproteinases (MMPs). Since animal models are frequently used for elucidating the disease mechanism and therapeutic development, it is relevant to study the ultrastructural characteristics and functional responses in human and mouse FLS. The objective of the study was to analyze ultrastructural characteristics, Interleukin-6 (IL-6) and Metalloproteinase-3 (MMP-3) production and the activation of intracellular pathways in Fibroblast like synoviocytes (FLS) cultures obtained from patients with rheumatoid arthritis (RA) and from mice with collagen-induced arthritis (CIA). Methods FLSs were obtained from RA patients (RA-FLSs) (n = 8) and mice with CIA (CIA-FLSs) (n = 4). Morphology was assessed by transmission and scanning electron microscopy. IL-6 and MMP-3 production was measured by ELISA, and activation of intracellular signaling pathways (NF-κB and MAPK: p-ERK1/2, p-P38 and p-JNK) was measured by Western blotting in cultures of RA-FLSs and CIA-FLSs stimulated with tumor necrosis factor-alpha (TNF-α) and IL-1β. Results RA-FLS and CIA-FLS cultures exhibited rich cytoplasm, rough endoplasmic reticula and prominent and well- developed Golgi complexes. Transmission electron microscopy demonstrated the presence of lamellar bodies, which are cytoplasmic structures related to surfactant production, in FLSs from both sources. Increased levels of pinocytosis and numbers of pinocytotic vesicles were observed in RA-FLSs (p < 0.05). Basal production of MMP-3 and IL-6 was present in RA-FLSs and CIA-FLSs. Regarding the production of MMP-3 and IL-6 and the activation of signaling pathways, the present study demonstrated a lower response to IL-1β by CIA-FLSs than by RA-FLSs. Conclusion This study provides a comprehensive understanding of the biology of RA-FLS and CIA-FLS. The differences and similarities in ultrastructural morphology and important inflammatory cytokines shown, contribute to future in vitro studies using RA-FLS and CIA-FLS, in addition, they indicate that the adoption of CIA-FLS for studies should take careful and be well designed, since they do not completely resemble human diseases.

7.
Front Microbiol ; 13: 973980, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36299729

RESUMO

Corals are treatened by global warming. Bleaching is one immediate effect of global warming, resulting from the loss of photosynthetic endosymbiont dinoflagellates. Understanding host-symbiont associations are critical for assessing coral's habitat requirements and its response to environmental changes. Cladocopium (formerly family Symbiodiniaceae clade C) are dominant endosymbionts in the reef-building coral, Mussismilia braziliensis. This study aimed to investigate the effect of temperature on the biochemical and cellular features of Cladocopium. Heat stress increased oxygen (O2) and decreased proteins, pigments (Chla + Chlc2), hexadecanoic acid- methyl ester, methyl stearate, and octadecenoic acid (Z)- methyl ester molecules. In addition, there was an increase in neutral lipids such as esterified cholesterol and a decrease in free fatty acids that may have been incorporated for the production of lipid droplets. Transmission electron microscopy (TEM) demonstrated that Cladocopium cells subjected to heat stress had thinner cell walls, deformation of chloroplasts, and increased lipid droplets after 3 days at 28°C. These findings indicate that thermal stress negatively affects isolated Cladocopium spp. from Mussismilia host coral.

8.
J Helminthol ; 96: e60, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35942907

RESUMO

The parasite biodiversity of mouse opossums in Brazil remains incompletely explored. We describe a new species of Subulura (Ascaridida: Subuluroidea) from the large intestine of the white-bellied woolly mouse opossum, Marmosa constantiae, based on the results of light and scanning electron microscopy (SEM). We also partially sequenced the mitochondrial cytochrome c oxidase I (MT-CO1) gene of the new species, using molecular phylogenetic analyses to determine its relationships within the Subuluroidea superfamily. As molecular data on subuluroid species are extremely limited, few inferences could be drawn from our phylogenies. Our SEM observations showed the detailed morphology of the cephalic extremity, precloacal pseudo-sucker, caudal papillae, phasmids and vulva. Subulura eliseae sp. n. differs from the other four Subulura parasites species of marsupials by the number of caudal papillae and the structure dimensions, and size of the spicule. Moreover, S. eliseae sp. n. has ten pairs of caudal papillae, which is unique compared to other species. We present morphometric and molecular data on this new species, contributing to future studies on subuluroids.


Assuntos
Ascaridídios , Parasitos , Animais , Brasil , Feminino , Camundongos , Gambás , Filogenia , Floresta Úmida
9.
Ciênc. rural (Online) ; 52(7): e20210449, 2022. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1369614

RESUMO

Edible coatings based on polysaccharides have been applied on pieces of fruits and vegetables before drying because of their potential to improve physical and nutritional characteristics of dehydrated plant foods. In the present study, physical and thermal properties of pectin-based films, with and without the incorporation of by-products obtained from the processing of red guava, were determined. These properties allow one to predict the likely behaviour of these films when used as edible coatings on guava pieces, during and after their dehydration. Thus the structural and morphological characteristics and the physical, thermal and sorption properties of the films and of the fruit pulp were determined, using scanning electronic microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and the static gravimetric method to determine the water-sorption curves. The addition of by-products provided crystallinity to the pectin film, attributed to their cellulose content, and hardly altered the water retention capacity of the pectin films. However, the pectin contributed to presenting a slightly higher sorption moisture at equilibrium, as compared to the guava pulp. The glass transition temperatures reported at extremely low moisture contents, both in the pulp and in the films with added by-products, indicated that at intermediate moisture contents, the fruit/film ensemble was in the rubbery state at room temperatures, providing softness to the dehydrated product. The images showed good integration of the edible films with the surface of the guava pieces.


Revestimentos comestíveis à base de polissacarídeos têm sido aplicados em pedaços de frutas e vegetais antes da secagem devido ao seu potencial de melhorar as características físicas e nutricionais de alimentos vegetais desidratados. No presente estudo, foram determinadas as propriedades físicas e térmicas de filmes à base de pectina, com e sem a incorporação de subprodutos obtidos do processamento da goiaba vermelha. Essas propriedades permitem prever o provável comportamento desses filmes quando usados ​​como cobertura comestível em pedaços de goiaba, durante e após a sua desidratação. Assim, foram determinadas as características estruturais e morfológicas e as propriedades físicas, térmicas e de sorção dos filmes e da polpa do fruto, utilizando microscopia eletrônica de varredura (MEV), calorimetria exploratória diferencial (DSC), difração de raios X (DRX) e método gravimétrico estático para determinação das curvas de sorção de água. A adição de subprodutos proporcionou cristalinidade ao filme de pectina, atribuída ao seu teor de celulose, e dificilmente alterou a capacidade de retenção de água dos filmes de pectina. No entanto, a pectina contribuiu para apresentar uma umidade de sorção ligeiramente superior no equilíbrio, quando comparada à polpa de goiaba. As temperaturas de transição vítrea encontradas em teores de umidade extremamente baixos, tanto na polpa quanto nos filmes com subprodutos adicionados, indicaram que em teores de umidade intermediários, o conjunto fruta / filme estava no estado borracha em temperatura ambiente, proporcionando maciez ao produto desidratado. As imagens mostraram boa integração dos filmes comestíveis com a superfície dos pedaços de goiaba.


Assuntos
Biopolímeros , Pectinas , Psidium , Fenômenos Químicos , Difração de Raios X , Varredura Diferencial de Calorimetria , Microscopia Eletrônica de Varredura
10.
Appl Radiat Isot ; 178: 109957, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34592693

RESUMO

Ceramic fragments can provide an insight into the ancient culture and practices of groups of humans and their way of life (technology, cultural identity, social organization, habitation and economy). Scientific analysis can be used to obtain information on the ceramic production process, as well as the specificities of the material employed. In this research, all samples of archaeological potsherd from the Tupi-Guarani tradition were analyzed in order to identify and to characterize the structures, morphologies and the elemental composition by using by scanning electron microscopy (SEM-EDS) and multivariate statistical methods (PCA and HCA). FTIR spectroscopy revealed the presence of an organic residue in three samples along with carbonates, clay minerals, quartz and hematite. In addition, the presence of the stretching attributed to water molecules in crystalline systems was observed. Also, the presence of TiO2 in the anatase polymorphic form was detected using µ-Raman spectroscopy. These results indicate a firing temperature of between 800 and 1000 °C. In relation to the morphology, all samples revealed amorphous structures presenting isolated and heterogenic particles of different forms and sizes, and the EDS spectrum confirmed the elements present in the molecular structures elucidated by vibrational spectroscopy. The multivariate analysis has confirmed the correlation between the elemental compositions of ceramics collected from two different sites: a mountain region and a coastal area in Santa Catarina State, Brazil.

11.
Braz. dent. j ; Braz. dent. j;31(6): 657-663, Nov.-Dec. 2020. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1132344

RESUMO

Abstract The aim of this study was to evaluate the effect of cleaning solutions on the retention force of o-ring-type overdenture attachments. The effect of four solutions on nitrile rings were evaluated: Cepacol (C), Cepacol with fluoride (CF), Listerine (L) and 0.05% sodium hypochlorite (SH); deionized water (DW) was used as a control. Matrices containing two implants and abutments and acrylic specimens with the metal capsules were obtained and divided into the groups. A simulation of 90 overnight immersions (8 h) was performed, and the tensile strength value was obtained at the beginning (T0) and in every 30 days (T1, T2 and T3) (n=6). In order to analyze o-ring surface damage after the immersions, a scanning electron microscopy (SEM) was used (n=1). For statistical analysis of the results, analysis of variance (ANOVA) and multiple comparisons with Bonferroni adjustment (test power=1.000; a=0.05) were used. There was a significant difference for the factors time (p<0.001), solution (p<0.001) and for the interaction time × solution (p<0.001). Considering the times of each solution, only for DW there was no significant loss of retention over time. Comparing the solutions in each moment, there was no difference among the solutions in T0. From T1, CF and SH provided less retention than DW (p<0.005). Through SEM it was possible to observe changes in the surface of the CF and SH nitrile o-rings. CF and SH should be avoided due to deleterious action in o-rings.


Resumo O objetivo do estudo foi avaliar o efeito de soluções higienizadoras sobre a força de retenção de encaixes do tipo o-ring. Foram avaliadas quatro soluções: Cepacol (C); Cepacol com flúor (CF), Listerine (L), hipoclorito de sódio 0,05% (HS) e água deionizada (controle/AD) em o-rings de nitrilo. Matrizes contendo dois implantes e pilares e espécimes em acrílico com as cápsulas metálicas foram obtidas e divididas entre os grupos. Foi realizada a simulação de 90 imersões noturnas (8 h), sendo obtido o valor da resistência à tração no início e a cada 30 dias (T0, T1, T2 e T3) por meio da máquina de ensaios mecânicos (n=6). Microscopia eletrônica de varredura (MEV) foi utilizada para análise de danos na superfície do o´ring após a imersão (n=1). Para análise estatística dos resultados foi utilizada análise de variância (ANOVA) e múltiplas comparações com ajuste de Bonferroni (poder do teste=1,000; a=0,05). Houve diferença significante para os fatores tempo (p<0,001), solução (p<0,001) e para interação de tempo × solução (p<0,001). Considerando-se os tempos de cada solução, apenas AD não apresentou perda significativa de retenção ao longo do tempo. Comparando as soluções em cada momento, não houve diferença entre as soluções em T0. A partir de T1, CF e HS propiciaram menor retenção quando comparados à AD (p <0,005). Através do MEV foi possível observar alterações nas superfícies dos o-rings de nitrilo imersos em CF e HS. O Cepacol com flúor e hipoclorito de sódio devem ser evitados devido à ação deletéria nos o-rings.


Assuntos
Hipoclorito de Sódio , Resistência à Tração , Teste de Materiais , Retenção de Dentadura , Prótese Dentária Fixada por Implante , Análise do Estresse Dentário , Revestimento de Dentadura
13.
Front Microbiol ; 11: 1076, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32582065

RESUMO

The antibiotic activity of metalloantibiotic compounds has been evaluated since the 90s, and many different modes of action were characterized. In the last decade, the effects of secondary metabolites produced by Pseudomonas aeruginosa LV strain, including a cupric compound identified as Fluopsin C, were tested against many pathogenic bacteria strains, proving their high antibiotic activity. In the present study, the bactericidal mechanisms of action of Fluopsin C and the semi-purified fraction F4A were elucidated. The results found in electron microscopy [scanning electron microscopy (SEM) and transmission electronic microscopy (TEM)] demonstrated that both Fluopsin C and F4A are affecting the cytoplasmatic membrane of Gram-positive and Gram-negative bacteria. These results were confirmed by fluorescence microscopy, where these bacteria presented permeabilization of their cytoplasmatic membranes after contact with the semi-purified fraction and pure compound. Using electronic and fluorescence microscopy, along with bacterial mutant strains with marked divisional septum, the membrane was defined as the primary target of Fluopsin C in the tested bacteria.

14.
Biotechnol Rep (Amst) ; 25: e00431, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32071895

RESUMO

Manganese (Mn) is toxic at higher concentrations requiring its removal before returning the wastewater to the environment. This article reported the Mn removal of two fungi strains isolated from mine wastewater. ITS rRNA region sequencing identified the fungi strains as Cladosporium halotolerans and Hypocrea jecorina. Mn2+ removal assays were performed in Sabouraud broth with 50 mg L-1 Mn2+ supplemented and bioleaching assays using MnO2 instead of MnSO4 at the same conditions. C. halotolerans removed 96 % of 50 mg L-1 Mn2+ at two weeks without MnO2 bioleaching with 649.9 mg of biomass and H. jecorina removed about 50 % of Mn2+ in 21 days from initial 50 mg of Mn2+ L-1 with 316.8 mg of biomass. Extracellular laccases were present in C. halotolerans agar regardless of the Mn addition. Mn adsorbed was detected on C. halotolerans hyphae. Mn oxidation was positive to H. jecorina by reaction of its medium with Leucoberbelin blue.

15.
Arch Dermatol Res ; 312(3): 223-227, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31531731

RESUMO

The pathogenesis of melasma is not fully understood, and the role of skin basement membrane zone (BMZ) alterations in disease development and the maintenance of hypermelanogenesis are also poorly known. We performed a comparative study to characterize the ultrastructural alterations that occur in BMZ in melasma and adjacent normal skin, as well as we discuss the implications of these changes in the physiopathology of the disease. Pairs of facial skin biopsies (2 mm) from 10 women with melasma and normal skin (< 2 cm apart) were processed by Transmission Electronic Microscopy or immunohistochemistry for Melan-A counterstained with Periodic acid-Schiff stain. Cytoplasmic organelles (from keratinocyte or melanocyte), BMZ damage were assessed and melanocyte counting (total and pendulous) was done. There was greater amount of cytoplasmic organelles inside basal keratinocytes and melanocytes in melasma, as well as structural damaged areas in the lamina densa (disruptions, gaps, lower density and thinning) and anchoring fibrils (lamina lucida), compared to healthy adjacent skin. Areas with pendulous melanocytes are characterized by discontinuity of BMZ ultrastructure. The prominence of cytoplasmic organelles from melanocytes and keratinocytes evidences the involvement of both cell groups in melasma. The damage in the lamina densa and lamina lucida suggest the role of upper dermis injury/repair process in the pathogenesis of the disease.


Assuntos
Membrana Basal/ultraestrutura , Face/patologia , Queratinócitos/patologia , Melanócitos/patologia , Melanose/patologia , Melanossomas/patologia , Pele/ultraestrutura , Humanos , Imuno-Histoquímica , Microscopia Eletrônica de Transmissão
16.
Front Microbiol ; 10: 2431, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31708901

RESUMO

The increasing emergence of multidrug-resistant (MDR) organisms in hospital infections is causing a global public health crisis. The development of drugs with effective antibiotic action against such agents is of the highest priority. In the present study, the action of Fluopsin C against MDR clinical isolates was evaluated under in vitro and in vivo conditions. Fluopsin C was produced in cell suspension culture of Pseudomonas aeruginosa LV strain, purified by liquid adsorption chromatography and identified by mass spectrometric analysis. Bioactivity, bacterial resistance development risk against clinically important pathogenic strains and toxicity in mammalian cell were initially determined by in vitro models. In vivo toxicity was evaluated in Tenebrio molitor larvae and mice. The therapeutic efficacy of intravenous Fluopsin C administration was evaluated in a murine model of Klebsiella pneumoniae (KPC) acute sepsis, using six different treatments. The in vitro results indicated MIC and MBC below 2 µg/mL and low bacterial resistance development frequency. Electron microscopy showed that Fluopsin C may have altered the exopolysaccharide matrix and caused disruption of the cell wall of MDR bacteria. Best therapeutic results were achieved in mice treated with a single dose of 2 mg/kg and in mice treated with two doses of 1 mg/kg, 8 h apart. Furthermore, acute and chronic histopathological studies demonstrated absent nephrotoxicity and moderate hepatotoxicity. The results demonstrated the efficacy of Fluopsin C against MDR organisms in in vitro and in vivo models, and hence it can be a novel therapeutic agent for the control of severe MDR infections.

17.
Rev. Ciênc. Méd. Biol. (Impr.) ; 18(2): 239-248, nov 07, 2019. fig, ilus
Artigo em Português | LILACS | ID: biblio-1291689

RESUMO

Introdução: associadas à composição química, as propriedades físicas dos biomateriais como formato, dimensões e porosidade, são fatores que influenciam na biocompatibilidade, biodegradabilidade e nos potenciais osteoindutivo e osteocondutores. Objetivo: identificar modificações físicas no formato, dimensões e porosidade de um biomaterial com nova composição de wollastonita e beta fosfato tricálcico, implantado em defeitos ósseos críticos em calvária de ratos. Metodologia: trata-se de um estudo exploratório, com um biomaterial compósito, antes e após a sua implantação in vivo. Utilizou-se explantes cirúrgicos de calvárias de ratos que receberam implantes em defeito ósseo crítico. Os animais foram distribuídos em 3 grupos experimentais aleatoriamente, compostos por 5 animais cada, e avaliados com 15, 45 e 120 dias. Os grupos foram denominados: G0-biomaterial; GI-15 dias; GII-45 dias; e, GIII-120 dias. As amostras foram micrografadas em microscópio eletrônico de varredura, com diferentes magnificações. Utilizouse o software livre ImageJ para processamento das imagens e análise das partículas e poros. Resultados: a distribuição espacial do biomaterial promoveu preenchimento completo do defeito ósseo crítico. Micrografias com diferentes magnificações permitiu identificar modificações na área de contato entre grânulos, diminuição dos poros intergranular, aumento da área ocupada pelos poros e diminuição das partículas nos grânulos. Nos grupos GII e GIII, identificou-se formação de componentes orgânicos na superfície do implante. Conclusão: houve modificações físicas no formato, dimensões horizontais, distribuição espacial e porosidade da superfície dos grânulos do biomaterial, relacionadas com a biodegradabilidade e o potencial osteoindutivo e osteocondutor do biomaterial.


Introduction: associated with the chemical composition, physical properties of biomaterials related to their format, dimensions and porosity, are factors that influence on biocompatibility, biodegradability and osteoinductive and osteoconductive potential. Objective: identify physical changes in the format, dimensions and porosity of biomaterial with new composition of wollastonite and beta tricalcium phosphate, implanted in critical bone defects in calvaria of rats. Methodology: this is an exploratory study, with a composite biomaterial before and after its implantation in vivo. Used surgical explants of rat calvarium that received biomaterial implants into the critical bone defect. The animals were divided into 3 experimental groups of random distribution, composed of 5 animals each, and evaluated for 15, 45 and 120 days. The groups were named: G0-Biomaterial; GI-15 days; GII-45 days; and, GIII-120 days. The samples were studied by micrography in scanning electronic microscope with different magnifications. It was used the free software ImageJ to image processing and particles and pores analysis. Results: the spatial distribution of the biomaterial promoted full filling of the critical bone defect. Micrographs with different magnifications allowed to identification of modifications in the area of contact between granules, decrease of the intergranular pores, increase of the area occupied by the pores and decrease of the particles in the granules. In GII, and GIII groups, it was identified formation of organic components on the surface of the implant. Conclusion: there were physical modifications in the format, horizontal dimensions, spatial distribution and porosity of the biomaterial, related to the biodegradability and the osteoinductive and osteoconductive potential of the biomaterial.


Assuntos
Regeneração Óssea
18.
Pesqui. vet. bras ; Pesqui. vet. bras;37(2): 183-194, fev. 2017. ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-834017

RESUMO

A avaliação hematológica, de importância comprovada como um meio auxiliar de diagnóstico ao clínico de pequenos animais domésticos, vem se tornando comum em animais selvagens não apenas para a clínica, mas para a avaliação do manejo e como estudo auxiliar para a fisiologia das várias espécies. Tendo em vista o aumento da demanda para a produção de várias drogas de importância farmacêutica, a criação de serpentes peçonhentas vem se tornando comum a ponto destes animais já serem reconhecidos como sendo de produção. O conhecimento do manejo e da clínica destes animais ainda é escasso e a mortalidade é elevada nos criatórios, tornando urgente a ampliação destes. Embora alguns estudos hematológicos já tenham sido realizados em cascavéis (Crotalus durissus) os dados analisados ainda são insipientes, notadamente em relação à caracterização das células do sangue e poucos estudos em microscopia eletrônica foram realizados em serpentes. Com o objetivo de caracterizar as células sanguíneas morfologicamente, sob microscopia óptica e ultraestrutural, foram coletadas amostras de sangue de 52 de indivíduos da subespécie Crotalus durissus terrificus para a realização de esfregaços sanguíneos e avaliação ultraestrutural. Concluiu-se que a coloração hematológica de Giemsa permite a avaliação morfológica e a diferenciação das células sanguíneas em serpentes assim como a visualização de hemoparasitos. A avaliação ultraestrutural permite evidenciar as organelas celulares e a diferenciação entre as células, inclusive entre os tipos leucocitários, porém ainda são necessários outros estudos para que seja elucidada a hipótese da existência dos eosinófilos na espécie estudada assim como é necessária melhor caracterização dos grânulos dos azurófilos para que se confirme uma possível diferença entre os monócitos típicos e os azurófilos.(AU)


Hematological evaluation, important for the diagnostic by the small domestic animal clinician, has become common in wildlife clinic, and for handling and study of the physiology of various species. Given the increased demand for drug production of pharmaceutical importance, the breeding of venomous snakes has become common and is already recognized as production. Knowledge of the management and clinics of snakes is still insufficient and their mortality is high. Although some hematological studies have already been conducted in the rattlesnake (Crotalus durissus), the analyzed data are still insufficient, especially with respect to the characterization of blood cells, and few electron microscopy studies have been performed on snakes. In order to characterize morphologically blood cells with light and ultrastructural microscopy, blood samples from 52 individuals of subspecies of Crotalus durissus terrificus were collected to perform blood smears and ultrastructural evaluation. It was concluded that hematologic Giemsa staining allows morphological evaluation and differentiation of the blood cells as well as of snake hemoparasites. The ultrastructural evaluation will highlight the cell organelles and differentiation between cells, including leukocyte types; although still further studies are needed to elucidate the hypothesis of eosinophils in the species studied as also is necessary a better characterization of azurophilic beads to confirm a possible difference between the typical monocyte and the azurophilic.(AU)


Assuntos
Animais , Células Sanguíneas/ultraestrutura , Crotalus/sangue , Leucócitos , Testes Hematológicos/veterinária , Microscopia Eletrônica/veterinária
19.
Pesqui. vet. bras ; 37(2): 183-194, fev. 2017. ilus
Artigo em Português | VETINDEX | ID: vti-688171

RESUMO

Hematological evaluation, important for the diagnostic by the small domestic animal clinician, has become common in wildlife clinic, and for handling and study of the physiology of various species. Given the increased demand for drug production of pharmaceutical importance, the breeding of venomous snakes has become common and is already recognized as production. Knowledge of the management and clinics of snakes is still insufficient and their mortality is high. Although some hematological studies have already been conducted in the rattlesnake (Crotalus durissus), the analyzed data are still insufficient, especially with respect to the characterization of blood cells, and few electron microscopy studies have been performed on snakes. In order to characterize morphologically blood cells with light and ultrastructural microscopy, blood samples from 52 individuals of subspecies of Crotalus durissus terrificus were collected to perform blood smears and ultrastructural evaluation. It was concluded that hematologic Giemsa staining allows morphological evaluation and differentiation of the blood cells as well as of snake hemoparasites. The ultrastructural evaluation will highlight the cell organelles and differentiation between cells, including leukocyte types; although still further studies are needed to elucidate the hypothesis of eosinophils in the species studied as also is necessary a better characterization of azurophilic beads to confirm a possible difference between the typical monocyte and the azurophilic.(AU)


A avaliação hematológica, de importância comprovada como um meio auxiliar de diagnóstico ao clínico de pequenos animais domésticos, vem se tornando comum em animais selvagens não apenas para a clínica, mas para a avaliação do manejo e como estudo auxiliar para a fisiologia das várias espécies. Tendo em vista o aumento da demanda para a produção de várias drogas de importância farmacêutica, a criação de serpentes peçonhentas vem se tornando comum a ponto destes animais já serem reconhecidos como sendo de produção. O conhecimento do manejo e da clínica destes animais ainda é escasso e a mortalidade é elevada nos criatórios, tornando urgente a ampliação destes. Embora alguns estudos hematológicos já tenham sido realizados em cascavéis (Crotalus durissus) os dados analisados ainda são insipientes, notadamente em relação à caracterização das células do sangue e poucos estudos em microscopia eletrônica foram realizados em serpentes. Com o objetivo de caracterizar as células sanguíneas morfologicamente, sob microscopia óptica e ultraestrutural, foram coletadas amostras de sangue de 52 de indivíduos da subespécie Crotalus durissus terrificus para a realização de esfregaços sanguíneos e avaliação ultraestrutural. Concluiu-se que a coloração hematológica de Giemsa permite a avaliação morfológica e a diferenciação das células sanguíneas em serpentes assim como a visualização de hemoparasitos. A avaliação ultraestrutural permite evidenciar as organelas celulares e a diferenciação entre as células, inclusive entre os tipos leucocitários, porém ainda são necessários outros estudos para que seja elucidada a hipótese da existência dos eosinófilos na espécie estudada assim como é necessária melhor caracterização dos grânulos dos azurófilos para que se confirme uma possível diferença entre os monócitos típicos e os azurófilos.(AU)


Assuntos
Animais , Crotalus/sangue , Células Sanguíneas/ultraestrutura , Leucócitos , Microscopia Eletrônica/veterinária , Testes Hematológicos/veterinária
20.
Biomed Pharmacother ; 87: 482-488, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28073097

RESUMO

Moringa oleifera has long been used in large demand in folk medicine to treat pain. The present study was undertaken to examine the antinociceptive and anti-inflammatory spectrum of M. oleifera leaf extracts discriminating the constituents' nature by using different kind of experimental models in rats. Pharmacological evaluation of a non-polar and/or polar extracts at several doses (30-300mg/kg, p.o.) was explored through experimental nociception using formalin test, carrageenan-induced paw edema and arthritis with subcutaneous injection of collagen in rats. Basic morphology characterization was done by scanning electronic microscopy and laser scanning confocal microscopy. Not only polar (from 30 or 100mg/kg, p.o.) but also non-polar extract produced significant inhibition of the nociceptive behavior with major efficacy in the inflammatory response in different assessed experimental models. This antinociceptive activity involved constituents of different nature and depended on the intensity of the induced painful stimulus. Phytochemical analysis showed the presence of kaempferol-3-glucoside in the polar extract and fatty acids like chlorogenic acid, among others, in the non-polar extract. Data obtained with M. oleifera leaf extracts give evidence of its potential for pain treatment.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Edema/tratamento farmacológico , Moringa oleifera/química , Dor/tratamento farmacológico , Animais , Feminino , Glucosídeos/farmacologia , Quempferóis/farmacologia , Masculino , Compostos Fitoquímicos/farmacologia , Fitoterapia/métodos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Ratos , Ratos Wistar
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