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1.
Sci Rep ; 10(1): 16099, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32999356

RESUMO

SARS-CoV-2 is the cause of the ongoing COVID-19 pandemic. Here, we investigated the interaction of this new coronavirus with Vero cells using high resolution scanning electron microscopy. Surface morphology, the interior of infected cells and the distribution of viral particles in both environments were observed 2 and 48 h after infection. We showed areas of viral processing, details of vacuole contents, and viral interactions with the cell surface. Intercellular connections were also approached, and viral particles were adhered to these extensions suggesting direct cell-to-cell transmission of SARS-CoV-2.


Assuntos
Betacoronavirus/ultraestrutura , Infecções por Coronavirus/transmissão , Interações Hospedeiro-Patógeno/fisiologia , Pneumonia Viral/transmissão , Animais , Linhagem Celular , Chlorocebus aethiops , Infecções por Coronavirus/patologia , Humanos , Microscopia Eletrônica de Varredura , Pandemias , Pneumonia Viral/patologia , Células Vero
2.
Zootaxa ; 4820(3): zootaxa.4820.3.7, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-33056060

RESUMO

The first zoeae of Alpheus formosus Gibbes, 1850 and Alpheus malleator Dana, 1852 are described and illustrated for the first time, based on laboratory-hatched larvae from parental females sampled in Vitória Island, Ubatuba, Brazil. Both species shared many characters with other species of genus Alpheus Fabricius, 1798, but they also have some exclusive characters as 10 setae on the basis of the maxilla, first maxilliped with endopod 2-segmented and exopod 4-segmented, second maxilliped with exopod 4-segmented, presence of bud only of the first pereopod, presence of anal spine and simple dorsal setae on the pleon. The zoea I of both species, nevertheless, can be separated by segmentation in the exopod of the antenna (8 in A. formosus, 6 in A. malleator); segmentation in the endopod and exopod of the third maxilliped (5 in A. formosus and 4 in A. malleator); peduncle of antennule 3-segmented in A. formosus (unsegmented or 2-segmented in other species) and presence of a medial tubercle in the proximal segment in the exopod of the antenna of A. malleator (absent in A. formosus, not reported in all other species). In this study three new characters are proposed to be analyzed in zoea of the genus Alpheus: presence of anal spine in both species (absent in Alpheus saxidomus Holthuis, 1980, but not reported in other species) and for the first time reported, presence of a tubercle in the exopod of the antenna (present only in A. malleator) and presence of simple dorsal setae on the pleon (both species), here analyzed under light and scanning electron microscopy.


Assuntos
Decápodes , Animais , Feminino , Larva , Microscopia Eletrônica de Varredura
3.
Zootaxa ; 4861(1): zootaxa.4861.1.8, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33055873

RESUMO

Promecostethus unifalculatus Enderlein, 1909, is the only representative of the order Opiliones from the Crozet Islands. The species belongs to the family Triaenonychidae and is biogeographically interesting because it is a candidate for transoceanic dispersal, a very rare event in this ancient family. Despite this significance, P. unifalculatus is taxonomically still poorly known, and a redescription of this species using modern taxonomic standards is urgently needed. Here we redescribe the species, offer the first description and illustrations of the male genitalia and provide a full exomorphological survey of the species using scanning electron microscopy. Furthermore, we provide an emended diagnosis for the genus Promecostethus and discuss its relationship with some morphologically similar genera.


Assuntos
Aracnídeos , Animais , Ilhas , Masculino , Microscopia Eletrônica de Varredura
4.
Zootaxa ; 4858(2): zootaxa.4858.2.10, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33056237

RESUMO

The designation of a neotype for Macrobiotus coronifer Richters, 1903 (now the type species of the genus Richtersius Pilato Binda, 1989) by Maucci Ramazzotti (1981) with type locality Bodø in Norway is shown to be invalid as it does not comply with the International Code of Zoological Nomenclature (Article 75.3.4). Furthermore, the specimen selected by Maucci Ramazzotti (1981) is not from the original type locality, and the superficial and outdated documentation prevent a reliable identification of the species. A Code-compliant neotype is therefore designated. The new neotype was collected from the original locus typicus in Svalbard and described with standard light microscopy, detailed scanning electron microscopy imaging, DNA barcodes and a transcriptome, which makes it ideally suited for stabilising the taxonomy and nomenclature of Richtersius coronifer (Richters, 1903).


Assuntos
Tardígrados , Animais , Microscopia Eletrônica de Varredura
5.
Zootaxa ; 4857(1): zootaxa.4857.1.11, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33056352

RESUMO

Tetranychus canadensis (McGregor) is redescribed based on type specimens and American non-type specimens. The ontogenetic development of leg chaetotaxy is provided, which is the typical additional pattern for Tetranychus. The variation of pregenital striae and shape of aedeagi are discussed.  Low temperature scanning electron microscopic photos show the supracoxal setae on palpfemur (ep) and leg coxae I (el) are eupathidia; lateral and ventral lips bear modified leaf-like adoral setae (or2 and or3) and the dorsal lips bearing a pair of spine-like dorsal adoral setae (or1); dorsal seta on tibia I (db) is a trichobothrium with a cup-shaped base and broken striae on the inner integument. Confocal scanning shows a thin, long ejaculatory duct and a thicker duct connecting the aedeagus to a cup-shaped seminal vesicle; the aedeagus is hollow where the ejaculatory duct passes through.


Assuntos
Tetranychidae , Animais , Temperatura Baixa , Tegumento Comum , Microscopia Eletrônica de Varredura , Pele
6.
Zootaxa ; 4789(2): zootaxa.4789.2.2, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-33056432

RESUMO

Hoverflies (Diptera: Syrphidae) of the genus Microdon Meigen have larvae that live in ant nests where they are predatory on ant larvae. Reflecting the exceptional challenges of this very specialized lifestyle, Microdon eggs, larvae and puparia are highly distinctive in their morphology. Detailed descriptions of these immature stages is, however, lacking for all but a very few species, and much of this has been limited through the sole use of light microscopes. Here, using Scanning Electron Microscopy (SEM), we present detailed, comparative descriptions of the immature stages of three European Microdon species: M. analis, M. devius and M. myrmicae. Given that many adult Microdon species are very similar to each other in their outward appearance, we demonstrate that the morphology of their immature stages can improve our understanding of the phylogeny of the genus. We also discuss how particular adaptations of the immature morphology may allow their myrmecophilous life within ant nests. In this paper new diagnostic features are also presented to distinguish M. myrmicae from its sibling species M. mutabilis-the two are morphologically indistinguishable as adults.


Assuntos
Dípteros , Scrophulariaceae , Adaptação Fisiológica , Animais , Larva , Microscopia Eletrônica de Varredura
7.
J Contemp Dent Pract ; 21(7): 776-780, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33020362

RESUMO

AIM: To evaluate the ability of osteogenic culture media in comparison with regular growth culture media in enhancing the osteoblastic cell differentiation of human periodontal ligament stem cells (hPDLSCs). MATERIALS AND METHODS: In vitro cultures of commercially obtained hPDLSCs were seeded onto xenograft bone blocks in both regular and osteogenic media. Confocal laser microscope images were obtained for cellular differentiation and adhesion, and scanning electron microscopy (SEM) images were obtained to validate the osteogenic differentiation by showing the morphological characteristics of the newly formed cells. RESULTS: Confocal laser microscope analysis showed positive staining for new bone cells with an increased signal intensity when samples were cultured in osteogenic culture media compared with regular culture media. These findings indicate the effect of the active ingredients of the osteogenic culture media in enhancing the osteogenic differentiation hPDLSC. Scanning electron microscopy images validated the osteogenic differentiation showing a flattened, polygonal morphology with multiple extending cytoplasmic processes of new cells. CONCLUSION: Xenograft bone blocks are biocompatible scaffold for the osteogenic differentiation of seeded hPDLSCs. Osteogenic culture media enhances and increases the osteogenic differentiation of hPDLSCs into new bone cells more than regular growth culture media. Periodontal ligament stem cells are a predictable biological input as a cell-based tissue-engineered construct and biologically acceptable when it is cultured in a suitable growth media that mimics the intended environment. CLINICAL SIGNIFICANCE: Consideration of the clinical use of equine bone blocks and periodontal ligament stem cells in a suitable biological environment as a potential new option for bone regeneration techniques.


Assuntos
Osteogênese , Ligamento Periodontal , Animais , Células Cultivadas , Meios de Cultura , Cavalos , Humanos , Microscopia Eletrônica de Varredura , Células-Tronco
8.
Stomatologiia (Mosk) ; 99(5): 19-24, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33034172

RESUMO

THE AIM OF THE STUDY: Was to evaluate the abrasive effect of toothpaste with detonation nanodiamonds synthesis of various concentrations on the enamel of human teeth. MATERIALS AND METHODS: The analysis of micrographs obtained by scanning electron microscopy showed a different abrasive and polishing effect of nanodiamonds in all the observed anatomical zones on the vestibular surface of the enamel of human teeth. RESULTS: No negative effect of the paste containing nanodiamonds on the enamel of human teeth was noted. At all concentrations of pastes containing nanodiamonds, on the vestibular surface of the enamel of the studied teeth, depot areas of densely attached particles of nanodiamonds were formed, a tendency was observed towards the formation of depots. The enamel of human teeth was mostly influenced by the concentration of nanodiamonds (2%, 2.5%). On the surface of the enamel were formed not only a depot of single nanodiamonds, but also accumulations were noted, merging into a layer in the form of a protective film. CONCLUSION: The study showed that toothpastes with nanoalases can reduce the enamel porosity, form a protective film on its surface, and thereby increase its microhardness and increase caries resistance.


Assuntos
Nanodiamantes , Dente , Esmalte Dentário , Humanos , Microscopia Eletrônica de Varredura , Cremes Dentais
9.
Zootaxa ; 4821(3): zootaxa.4821.3.9, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-33056317

RESUMO

Sarcophaga (Hoa) membranijuxta sp. nov. is described from the Chinese provinces Guangxi and Hainan and documented with illustrations, photographs and scanning electron microscopy images. The habitus and male terminalia of Sarcophaga (Hoa) basiseta Baranov, 1931 are documented with photographs for the first time, and the circumscription and distribution of the subgenus Hoa Rohdendorf, 1937 are updated.


Assuntos
Dípteros , Sarcofagídeos , Animais , China , Masculino , Microscopia Eletrônica de Varredura
10.
Korean J Parasitol ; 58(4): 403-411, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32871634

RESUMO

Adult ascarid worms from the field mice, Apodemus agrarius, were observed with a light and scanning electron microscope, and molecularly analized with 18S rRNA gene. In the scanning electron microscope, 3 prominent labia were present in the anterior end of male and female worms, but the interlabia and gubernaculum were absent. Scanning electron micrographs showed cervical alae as vestigial organs that looked like a slightly uplifted superficial sewing stitch. Total 6 pairs of post-cloacal papillae were observed on the tail of the male worms. The tail of female worms was blunt and conical shape with a spine-like structure, mucron. The eggs were sub-globular, coated with the albuminous layer and 73 by 82 µm in average size. The superficial pits of T. apodemi egg (mean 8.6×6.7 µm) are obviously bigger than those of Toxocara spp. The partial sequence of 18S rRNA showed the sequence homology of Toxocara canis (99.6%), Toxocara cati (99.4%), Toxascaris leonina (99.4%), and Toxocara vitulorum (99.2%). Conclusively, it was confirmed that ascarid nematodes, Toxocara apodemi, recovered from striped field mice in Korea are taxonomically conspecific relationship with genus Toxocara and genetic divergence from other Toxocara species.


Assuntos
Murinae/parasitologia , Toxocara/genética , Toxocara/ultraestrutura , Animais , Feminino , Humanos , Masculino , Microscopia Eletrônica de Varredura , RNA de Helmintos/genética , RNA Ribossômico 18S/genética , República da Coreia , Toxocara/classificação , Toxocara/isolamento & purificação
11.
Biosens Bioelectron ; 166: 112431, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32862842

RESUMO

Last few decades, viruses are a real menace to human safety. Therefore, the rapid identification of viruses should be one of the best ways to prevent an outbreak and important implications for medical healthcare. The recent outbreak of coronavirus disease (COVID-19) is an infectious disease caused by a newly discovered coronavirus which belongs to the single-stranded, positive-strand RNA viruses. The pandemic dimension spread of COVID-19 poses a severe threat to the health and lives of seven billion people worldwide. There is a growing urgency worldwide to establish a point-of-care device for the rapid detection of COVID-19 to prevent subsequent secondary spread. Therefore, the need for sensitive, selective, and rapid diagnostic devices plays a vital role in selecting appropriate treatments and to prevent the epidemics. During the last decade, electrochemical biosensors have emerged as reliable analytical devices and represent a new promising tool for the detection of different pathogenic viruses. This review summarizes the state of the art of different virus detection with currently available electrochemical detection methods. Moreover, this review discusses different fabrication techniques, detection principles, and applications of various virus biosensors. Future research also looks at the use of electrochemical biosensors regarding a potential detection kit for the rapid identification of the COVID-19.


Assuntos
Betacoronavirus , Técnicas Biossensoriais/instrumentação , Técnicas de Laboratório Clínico/instrumentação , Infecções por Coronavirus/diagnóstico , Técnicas Eletroquímicas/instrumentação , Pneumonia Viral/diagnóstico , Vírus/isolamento & purificação , Animais , Betacoronavirus/isolamento & purificação , Betacoronavirus/patogenicidade , Infecções por Coronavirus/virologia , Desenho de Equipamento , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Pandemias , Pneumonia Viral/virologia , Testes Imediatos , Vírus/patogenicidade
12.
Environ Health Prev Med ; 25(1): 56, 2020 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-32979924

RESUMO

BACKGROUND: We previously demonstrated that continuous exposure to nitrous acid gas (HONO) for 4 weeks, at a concentration of 3.6 parts per million (ppm), induced pulmonary emphysema-like alterations in guinea pigs. In addition, we found that HONO affected asthma symptoms, based on the measurement of respiratory function in rats exposed to 5.8 ppm HONO. This study aimed to investigate the dose-response effects of HONO exposure on the histopathological alterations in the respiratory tract of guinea pigs to determine the lowest observed adverse effect level (LOAEL) of HONO. METHODS: We continuously exposed male Hartley guinea pigs (n = 5) to four different concentrations of HONO (0.0, 0.1, 0.4, and 1.7 ppm) for 4 weeks (24 h/day). We performed histopathological analysis by observing lung tissue samples. We examined samples from three guinea pigs in each group under a light microscope and measured the alveolar mean linear intercept (Lm) and the thickness of the bronchial smooth muscle layer. We further examined samples from two guinea pigs in each group under a scanning electron microscope (SEM) and a transmission electron microscope (TEM). RESULTS: We observed the following dose-dependent changes: pulmonary emphysema-like alterations in the centriacinar regions of alveolar ducts, significant increase in Lm in the 1.7 ppm HONO-exposure group, tendency for hyperplasia and pseudostratification of bronchial epithelial cells, and extension of the bronchial epithelial cells and smooth muscle cells in the alveolar duct regions. CONCLUSIONS: These histopathological findings suggest that the LOAEL of HONO is < 0.1 ppm.


Assuntos
Enfisema/induzido quimicamente , Hiperplasia/induzido quimicamente , Exposição por Inalação/efeitos adversos , Pulmão/patologia , Ácido Nitroso/toxicidade , Células Epiteliais Alveolares/efeitos dos fármacos , Animais , Brônquios/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Cobaias , Pulmão/efeitos dos fármacos , Pulmão/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Miócitos de Músculo Liso/efeitos dos fármacos
13.
Acta Odontol Latinoam ; 33(2): 117-124, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920614

RESUMO

The aim of this study was to evaluate the ability of different irrigation protocols to remove from the walls of the root canal and entrance to dentinal tubules the smear layer produced during preparation for a fiber post. Fifty decoronated human lower premolars were treated endodontically and the apical third of the canal was filled with a single gutta-percha point using warm vertical compaction. Ten millimeters were left free for post preparation, which was done by sequential use of a Largo #1 drill and Exacto #3 pilot drill (Angelus, Brazil), with irrigation with distilled water upon each instrument change. Samples were distributed randomly into 5 groups (n=10). G 1: No irrigation after post preparation. G 2: Distilled water activated for 60 s + distilled water. G 3: 5.25% NaOCl 15 s+ distilled water. G 4: 17% EDTA (Farmadental, Argentina) 60 s + 5.25% NaOCl 15 s + distilled water. G 5: 10% polyacrylic acid (Densell) 15 s + distilled water. Irrigant was activated mechanically with a low-speed conical brush. Roots were then split longitudinally in vestibular-lingual direction. Each surface was observed under SEM in its different thirds. Microphotographs were taken at 150X and 600X magnification and results analyzed statistically using Kruskall Wallis and Friedman tests (p<0.05). The results [mean (standard deviation)] were: for 150X: G1 11.00 (1.33), G2 7.50 (3.13), G3 6.30 (2.58), G4 2.20 (2.80), G5 4.30 (1.50), and for 600X G1 11.40 (0.84), G2 10.00 (1.94), G3 7.70 (3.33), G4 5.80 (3.70), G5 7.20 (2.65). The statistical analysis showed significant differences between irrigants (p<0.05) but not between root thirds (p>0.05). The EDTA+NaOCl combination and polyacrylic acid showed greater capacity to remove the smear layer created during post preparation.


Assuntos
Cavidade Pulpar/efeitos dos fármacos , Irrigantes do Canal Radicular/farmacologia , Preparo de Canal Radicular/métodos , Cavidade Pulpar/diagnóstico por imagem , Humanos , Microscopia Eletrônica de Varredura , Irrigantes do Canal Radicular/administração & dosagem , Camada de Esfregaço
14.
Int J Prosthodont ; 33(5): 523-526, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32956433

RESUMO

PURPOSE: To investigate the three-point flexural strength of a novel CAD/CAM fiber-reinforced composite (FRC) material following different aging conditions. MATERIALS AND METHODS: The specimens were randomly assigned to one of five groups based on aging condition: (1) control (no treatment); (2) short-term water storage; (3) thermal degradation with autoclaving; (4) chemical degradation with hydrochloric acid; and (5) chemical degradation with citric acid (n = 10 per group). The specimens in the control group received no treatment. Following each treatment protocol, the three-point bending test was used to calculate the flexural strength. Data were statistically analyzed (α = .05), and scanning electron microscopy (SEM) analysis of the specimens was conducted. RESULTS: No significant differences in flexural strength were observed among the groups (P = .199). In addition, no distinct morphologic differences were detected in the SEM images of the specimens. CONCLUSION: The flexural strength of this novel CAD/CAM FRC material was unaffected by different aging methods.


Assuntos
Resinas Compostas , Resistência à Flexão , Desenho Assistido por Computador , Teste de Materiais , Microscopia Eletrônica de Varredura , Projetos Piloto , Maleabilidade , Estresse Mecânico , Propriedades de Superfície
15.
Oral Health Prev Dent ; 18(1): 747-756, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32895658

RESUMO

PURPOSE: This in vitro study evaluated the effectiveness of polyacrylic acid as an acid etchant similar to phosphoric acid and its effect on the microtensile bond strength of self-adhesive resin cement to enamel. MATERIALS AND METHODS: Ninety Te-Econom Plus resin blocks (11 x 4 mm) were cemented onto bovine enamel and distributed into 10 groups according to the surface treatments (no surface treatment; etching with 37% phosphoric acid; etching with 20% polyacrylic acid; etching with 37% phosphoric acid + dental adhesive, and etching with 20% polyacrylic acid + dental adhesive) and the self-adhesive resin cements used (RelyX U200 and MaxCem Elite) (n = 9). After bonding, the specimens were sectioned into sticks, subjected to thermocycling (5760 cycles, 5°C and 55°C) and microtensile bond strength testing (n = 6). Images of representative specimens were obtained using a scanning electron microscope. Enamel penetration evaluation of different surface treatments was analysed by confocal laser scanning microscopy (n = 3). Data on bond strength were subjected to 2-way ANOVA and Tukey's least significant difference test (α = 0.05). RESULTS: Both 37% phosphoric acid and 20% polyacrylic acid yielded the same microtensile bond strength between self-adhesive resin cement and enamel, independent of the application of dental adhesives (p > 0.05). MaxCem Elite showed higher bond strength values than RelyX U200 just for the 20% polyacrylic acid group (p = 0.001). CONCLUSION: Acid pre-conditioning of dental enamel may influence the bond strength of self-adhesive resin cement to enamel, and 20% polyacrylic acid showed efficacy similar to that of 37% phosphoric acid.


Assuntos
Colagem Dentária , Cimentos de Resina , Condicionamento Ácido do Dente , Resinas Acrílicas , Animais , Bovinos , Resinas Compostas , Cimentos Dentários , Esmalte Dentário , Análise do Estresse Dentário , Teste de Materiais , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Resistência à Tração
17.
Waste Manag ; 116: 140-146, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32799095

RESUMO

Integrated gasification combined cycle (IGCC) is a highly efficient method for producing electricity but discharges a byproduct in the form of a glassy slag, similar to other electricity generation operations. Several technologies for recycling IGCC slag have been developed thus far, although the results obtained are not promising or universally applicable. We quantitatively characterized an IGCC slag by using various testing methods, including an automated scanning electron microscopy-energy dispersive spectrometry (SEM-EDS) system, to recognize its potential for recycling. The IGCC slag did not contain free CaO, and the absence of free lime would address a concern of volumetric expansion during hydration. Automated SEM-EDS analysis revealed that approximately 98% of the IGCC slag particles consisted of calcium-rich aluminosilicate materials. Obvious differences in the concentrations of Si, Al, and Ca between the amorphous phases and the average chemical bulk were recognized. The chemical composition of the amorphous Si-Al-Ca phases was similar to that of Class C fly ash, while the average bulk composition of the IGCC slag was in between that of Class C and Class F fly ashes. Considering this discrepancy, understanding the dissolution mechanism of the reactive amorphous fraction as well as an exact assessment of the reaction products based on the role of Ca in alkali-activated materials provides a new approach for the valorization of IGCC slag.


Assuntos
Cinza de Carvão , Reciclagem , Microscopia Eletrônica de Varredura
18.
PLoS One ; 15(8): e0237795, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32833989

RESUMO

Extracellular vesicles (EVs) are small membrane-limited structures derived from outward budding of the plasma membrane or endosomal system that participate in cellular communication processes through the transport of bioactive molecules to recipient cells. To date, there are no published methodological works showing step-by-step the isolation, characterization and internalization of small EVs secreted by human primary macrophages derived from circulating monocytes (MDM-derived sEVs). Thus, here we aimed to provide an alternative protocol based on differential ultracentrifugation (dUC) to describe small EVs (sEVs) from these cells. Monocyte-derived macrophages were cultured in EV-free medium during 24, 48 or 72 h and, then, EVs were isolated from culture supernatants by (dUC). Macrophages secreted a large amount of sEVs in the first 24 h, with size ranging from 40-150 nm, peaking at 105 nm, as evaluated by nanoparticle tracking analysis and scanning electron microscopy. The markers Alix, CD63 and CD81 were detected by immunoblotting in EV samples, and the co-localization of CD63 and CD81 after sucrose density gradient ultracentrifugation (S-DGUC) indicated the presence of sEVs from late endosomal origin. Confocal fluorescence revealed that the sEVs were internalized by primary macrophages after three hours of co-culture. The methodology here applied aims to contribute for enhancing reproducibility between the limited number of available protocols for the isolation and characterization of MDM-derived sEVs, thus providing basic knowledge in the area of EV methods that can be useful for those investigators working with sEVs released by human primary macrophages derived from circulating monocytes.


Assuntos
Comunicação Celular , Vesículas Extracelulares/metabolismo , Macrófagos/metabolismo , Buffy Coat/citologia , Diferenciação Celular , Fracionamento Celular/métodos , Centrifugação com Gradiente de Concentração/métodos , Técnicas de Cocultura , Voluntários Saudáveis , Humanos , Microscopia Intravital , Macrófagos/citologia , Macrófagos/ultraestrutura , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Monócitos/fisiologia , Cultura Primária de Células
19.
PLoS One ; 15(8): e0237452, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764805

RESUMO

The lady beetle Hippodamia variegata is an important biocontrol agent of many aphids. In this study, the fine morphology of antennae as well as the typology, morphology and distribution of antennal sensilla were comprehensively examined by scanning electron microscopy. The antennal morphology of female and male are similar and consist of the scape, pedicel, and nine flagellomeres. No significant difference was detected in the length of each segment between two sexes, while the male antennae are much stronger than females. In total, six types of sensilla can be defined on antenna, including Böhm bristle, sensilla chaetica (with three subtypes), sensilla basiconica (with three subtypes), sensilla trichodea, sensilla placodea and sensilla coeloconica. It is worth noting that sensilla chaetica III distributed only on the fixed position of male antennae. In addition, the functional morphology of antennae of H. variegata were compared with other lady beetles from multiple perspectives. Specially, the function of sensilla were also discussed according to their morphology, location and information from previous studies.


Assuntos
Antenas de Artrópodes/fisiologia , Besouros/fisiologia , Animais , Antenas de Artrópodes/anatomia & histologia , Besouros/anatomia & histologia , Feminino , Processamento de Imagem Assistida por Computador , Masculino , Microscopia Eletrônica de Varredura , Sensilas/anatomia & histologia , Sensilas/fisiologia
20.
PLoS One ; 15(8): e0237195, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764819

RESUMO

This study investigated the caries-preventive effect of 445 nm laser radiation in combination with fluoride on the prevention of white spot lesions. Previously, several studies have indicated the ability of 488 nm argon ion laser irradiation to reduce early enamel demineralization. A diode laser (445 nm) could be an alternative technology for possible caries-preventive potential. Each sample of a group of seventeen caries-free bovine teeth was treated in four different ways on four different zones of the labial surface: control/no treatment (C), laser irradiation only (L) (0.3 W, 60 s and applied dose of 90 J/cm2), amine fluoride application only (10,000 ppm and pH 3.9) (F), and amine fluoride application followed by laser irradiation (FL). After treatment, the teeth were subjected to a demineralization solution (pH 4.3 for 48 h at 37 °C) to induce subsurface lesions. After sectioning, the teeth were examined by light microscopy. Three teeth were analyzed by scanning electron microscopy (SEM). The depths of the subsurface lesions in the C, L, F, and FL groups were 103.01 (± 13.04), 96.99 (± 14.51), 42.59 (± 17.13), and 24.35 (± 11.38) µm, respectively. The pairwise group comparison showed the following results: p < 0.001 for FL versus C, FL versus L, F versus C, and F versus L, p = 0.019 for FL versus F and p = 0.930 for L versus C. The SEM micrographs support the light-microscopic examination. The results of the current study have shown that using relatively low irradiation settings of 445 nm laser on fluoridated enamel may be effective for prevention of white spot lesions.


Assuntos
Cárie Dentária/prevenção & controle , Fluoretos Tópicos/administração & dosagem , Terapia com Luz de Baixa Intensidade/métodos , Desmineralização do Dente/prevenção & controle , Animais , Bovinos , Terapia Combinada/métodos , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/efeitos da radiação , Esmalte Dentário/ultraestrutura , Humanos , Lasers Semicondutores/uso terapêutico , Microscopia Eletrônica de Varredura
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