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1.
Phys Chem Chem Phys ; 21(36): 20083-20094, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31482893

RESUMO

The formation of amyloid aggregates is the hallmark of many protein misfolding diseases, including Type-II diabetes mellitus, which is caused by the fibrillation of amylin protein. It is established that nano-sized ligands such as curcumin, resveratrol and graphene quantum dots can modify protein aggregation rates. In this article, we report a comparative study of these ligands to estimate their protein aggregation rates and fluorescence quenching using various experimental techniques. Through light scattering experiments, the RH of bare amylin was found to increase at a rate of 43% per day, whereas in the presence of the ligands in different molar ratios (A1C10, A1R10 and A1GQDs20), the sizes of the complexes were found to grow at rates of 7%, 8% and 13% per day, respectively. We observed fluorescence quenching using photoluminescence experiments for all three protein-ligand complexes. The protein aggregation rate and fluorescence quenching exhibited a concentration-dependent competitive role in the inhibition process. Interestingly, for graphene quantum dots, the protein aggregation rate is more affected at lower concentrations, while fluorescence quenching dominates at higher concentrations; this is in contrast to curcumin and resveratrol, where fluorescence quenching dominates at all concentrations of the ligands in the complex. The FTIR data showed appreciable conversion of ß-sheets into less aggregation-prone secondary structures for all three amylin-ligand ratios; however, the inhibition performance of curcumin overshadowed those of the other two inhibitors. The inhibition behavior of these three ligands was corroborated by analysis of analytical and high-resolution TEM images of the fibrils.


Assuntos
Modelos Químicos , Agregação Patológica de Proteínas , Fluorescência , Polipeptídeo Amiloide das Ilhotas Pancreáticas/antagonistas & inibidores , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/ultraestrutura , Microscopia Eletrônica de Transmissão
2.
An Acad Bras Cienc ; 91(3): e20180959, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31553369

RESUMO

The genus Dermocystidium is very comprehensive in the host and site of infection, however this is the first report of the occurrence of Dermocystidium sp. in the gills of Nile tilapia. This study was carried out in a fish farming located in the state of Santa Catarina, Brazil. No mortalities were reported in the facility studied and the animals were clinically healthy. During the histopathological analysis of the gills, 8.33% of the fish presented spores of Dermocystidium sp. in the gill tissue. The spores reported herein had a mean length and width of 6.206 x 5.233 µm and a refractile body diameter of 1.965 µm and were studied by histopathology and Transmission Electron Microscopy. This study highlights the importance of a new branchial pathogen in farmed tilapia, as well as to its pathogenic potential, considering the outbreaks of mortalities associated with other fish species.


Assuntos
Ciclídeos/parasitologia , Doenças dos Peixes/parasitologia , Infecções por Mesomycetozoea/parasitologia , Mesomycetozoea/isolamento & purificação , Animais , Aquicultura , Brasil , Mesomycetozoea/ultraestrutura , Microscopia Eletrônica de Transmissão
3.
Acta Virol ; 63(3): 270-277, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507192

RESUMO

Orf, also called contagious ecthyma or contagious pustular dermatitis, is a significant zoonotic disease that primarily affects goat and sheep globally. Currently, the infection by orf virus (ORFV) has been observed in different host species worldwide, including China. Here, a suspected outbreak of orf infection in a goat farm in Anhui Province in 2018 was investigated. Through PCR, electron microscopy, and cell culture techniques, we confirmed that the outbreak was caused by ORFV. Consequently, the orf virus strain was named the AH/LA/2018 strain. The amplified and sequenced ORFV011 (B2L) and ORFV059 (F1L) genes were used to construct phylogenetic trees to elucidate the genetic characteristics of the ORFV and the molecular epidemiology of orf. The present study is the first systematic evolution analysis of the ORFV strain isolated in Anhui Province. The results of this study will be helpful to better understand the characteristics of ORFV, to help prevent and control the transmission of ORFV at an early stage in China. Keywords: Anhui Province; goat; orf virus; phylogenetic analysis.


Assuntos
Ectima Contagioso , Vírus do Orf , Filogenia , Animais , Células Cultivadas , China/epidemiologia , Ectima Contagioso/virologia , Genes Virais/genética , Doenças das Cabras/epidemiologia , Doenças das Cabras/virologia , Cabras , Microscopia Eletrônica de Transmissão , Vírus do Orf/classificação , Vírus do Orf/ultraestrutura , Reação em Cadeia da Polimerase , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/virologia
4.
Mem Inst Oswaldo Cruz ; 114: e190147, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31553371

RESUMO

BACKGROUND: Calpains are proteins belonging to the multi-gene family of calcium-dependent cysteine peptidases that undergo tight on/off regulation, and uncontrolled proteolysis of calpains is associated with severe human pathologies. Calpain orthologues are expanded and diversified in the trypanosomatids genome. OBJECTIVES: Here, we characterised calpains in Leishmania braziliensis, the main causative agent of cutaneous leishmaniasis in Brazil. METHODS/FINDINGS: In total, 34 predicted calpain-like genes were identified. After domain structure evaluation, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) during in vitro metacyclogenesis revealed (i) five genes with enhanced expression in the procyclic stage, (ii) one augmented gene in the metacyclic stage, and (iii) one procyclic-exclusive transcript. Western blot analysis revealed that an antibody against a consensus-conserved peptide reacted with multiple calpain-like proteins, which is consistent with the multi-gene family characteristic. Flow cytometry and immunocytochemistry analyses revealed the presence of calpain-like molecules mainly in the cytoplasm, to a lesser extent in the plasma membrane, and negligible levels in the nucleus, which are all consistent with calpain localisation. Eventually, the calpain inhibitor MDL28170 was used for functional studies revealing (i) a leishmaniostatic effect, (ii) a reduction in the association index in mouse macrophages, (iii) ultra-structural alterations conceivable with autophagy, and (iv) an enhanced expression of the virulence factor GP63. CONCLUSION: This report adds novel insights into the domain structure, expression, and localisation of L. braziliensis calpain-like molecules.


Assuntos
Calpaína/genética , Genoma de Protozoário/genética , Leishmania braziliensis/química , Macrófagos Peritoneais/metabolismo , Animais , Western Blotting , Calpaína/efeitos dos fármacos , Calpaína/metabolismo , Calpaína/ultraestrutura , Inibidores de Cisteína Proteinase/farmacologia , Dipeptídeos/farmacologia , Citometria de Fluxo , Regulação da Expressão Gênica , Imuno-Histoquímica , Leishmania braziliensis/genética , Leishmania braziliensis/metabolismo , Leishmania braziliensis/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Virulência
5.
Rev Soc Bras Med Trop ; 52: e20190135, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31390442

RESUMO

INTRODUCTION: Musca domestica is resistant to many insecticides; hence, biological control is a suitable alternative. METHODS: We evaluated the lethality of strain Btk176 towards the larval and adult M. domestica and the histopathological effects in the larvae midgut. RESULTS: We observed 99% larval and 78.9% adult mortality within 48 hours of spore ingestion (dosage, 2.4×108 CFU/ml). The histopathological effects were consistent with cytotoxicity. PCR analysis showed the presence of the cry1Ba gene. Transmission electron microscopy revealed a bipyramidal parasporal body. Thurigiensin activity was not detected. CONCLUSIONS: The serovar, Btk176 might be a potential biocontrol agent for houseflies.


Assuntos
Bacillus thuringiensis , Toxinas Bacterianas/farmacologia , Moscas Domésticas/efeitos dos fármacos , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Análise de Variância , Animais , Contagem de Colônia Microbiana , Exotoxinas , Microscopia Eletrônica de Transmissão , Controle Biológico de Vetores/métodos , Reprodutibilidade dos Testes
6.
Chem Commun (Camb) ; 55(70): 10444-10447, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31410430

RESUMO

A new series of 2D catalytic materials whose inorganic surfaces are fully covered with pre-designed "promoter" groups are reported. One of them showed excellent biomimetic catalytic activity and provided the lowest detection limit to glucose among the reported 2D materials and their composite materials.


Assuntos
Biomimética , Calcogênios/química , Metais/química , Catálise , Limite de Detecção , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Espectroscopia Fotoeletrônica , Difração de Pó
7.
Eur J Histochem ; 63(3)2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31455072

RESUMO

The aim of this study was to describe the structural and ultrastructural aspects of the myotendinous junction (MTJ) and the proximal and distal sarcomeres of the sternomastoid of aged Wistar rats subjected to an experimental model of menopause and swimming training. A total of 20 female elderly rats were divided into the following four groups (n=5 in each group): sedentary/no-menopausal (SNM), trained/no-menopausal (TNM), sedentary/menopausal (SM), and trained/menopausal (TM). The MTJ samples were dissected and analyzed using transmission electron microscopy. We showed that the TNM Group rats exhibited changes in morphological characteristics as a consequence of physical exercise, which included an increase of 36.60% (P<0.001) in the evagination length of the MTJ and a reduction in the length of the distal (77.38%) (P<0.0001) and proximal (68.15%) (P<0.0001) sarcomeres. The SM Group exhibited a reduction of about 275.93% (P<0.001) in the muscle-tendon interface and in the lengths of distal sarcomeres (55.87%) (P<0.0001) compared with SNM Group. Our results suggest that the swimming training under experimental model of menopause promoted tissue reorganization and increased muscle-tendon interaction with a drastic development in the length and thickness of the sarcoplasmatic invaginations and evaginations. In addition, the sarcomeres exhibited different lengths and a reduction in both groups subjected to swimming training.


Assuntos
Menopausa/fisiologia , Músculos do Pescoço/metabolismo , Condicionamento Físico Animal , Sarcômeros/metabolismo , Tendões/metabolismo , Animais , Feminino , Microscopia Eletrônica de Transmissão , Músculos do Pescoço/ultraestrutura , Ratos Wistar , Sarcômeros/ultraestrutura , Natação , Tendões/ultraestrutura
8.
Chem Commun (Camb) ; 55(66): 9829-9832, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31363730

RESUMO

Polyethylene glycol grafted pyrrole-based conjugated polymers are synthesized through a one-pot multicomponent methodology, the self-assemblies of which enable nanoparticle size-selective encapsulation of drug molecules and their sustained release. Efficient loading of curcumin through drug-nanoparticle core interactions is probed using FRET, and the inherently fluorescent nature of polypyrrole could be used to detect these nanocarriers intracellularly.


Assuntos
Portadores de Fármacos , Nanopartículas/química , Polietilenoglicóis/química , Polímeros/química , Pirróis/química , Linhagem Celular Tumoral , Curcumina/administração & dosagem , Transferência Ressonante de Energia de Fluorescência , Humanos , Interações Hidrofóbicas e Hidrofílicas , Concentração Inibidora 50 , Microscopia Eletrônica de Transmissão , Espectrofotometria Ultravioleta
9.
Chem Commun (Camb) ; 55(66): 9865-9868, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31364624

RESUMO

Au hydrogel with a well-defined nanowire network was rationally designed through one-step dopamine-induced self-assembly. Due to the porous nanostructure along with the polydopamine induced accumulation and interfacial electron transfer effects, the resulting Au hydrogel nanozyme exhibits enhanced glucose oxidase-like activity and peroxidase-like activity, with a biomimetic cascade catalysis.


Assuntos
Biomimética , Dopamina/química , Glucose Oxidase/química , Ouro/química , Hidrogéis/química , Nanopartículas Metálicas/química , Peroxidase/química , Catálise , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Oxirredução
10.
Exp Parasitol ; 204: 107732, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31374184

RESUMO

In the present study, the cytotoxic effects of amitraz, an octopamine receptor agonist on the reproductive system of engorged adult females of Rhipicephalus (Boophilus) annulatus were assessed using histology, electron microscopy and octopamine beta (OCTß) receptor transcriptional expression analysis. Adult immersion test (AIT) was performed by immersing the fully engorged female ticks for 2 min in different concentrations of amitraz (200, 250, 300, 350 ppm). Amitraz at the dose of 300 ppm, caused an adult tick mortality of 16.66 ±â€¯6.80 per cent, inhibition of fecundity of 75.80 per cent and hatching of 50 per cent of ova laid by treated ticks. Histological changes in the ovaries of ticks collected after 24 h of treatment with amitraz (300 ppm), in comparison with controls (distilled water/methanol) were identified by microscopical examination of sections (4  µm) stained using haematoxylin and eosin. These changes included reduction in size and basophilia of stage I oocytes, presence of cytoplasmic vacuoles of various sizes around germinal vesicle of stage II oocytes, wavy basement membrane of stage III oocytes and reduction in size and number of mature stage IV and V oocytes. Electron microscopy was employed for understanding the structural changes in the ultrathin sections (60 nm) of ovaries. Ticks treated with amitraz showed major ultrastructural changes such as irregular nuclear membrane, crystolysis of mitochondria and detachment of external and internal layers of basal lamina of oocytes. The cDNA synthesized from the total RNA of whole ticks and ovaries of ticks treated with amitraz along with controls were used for relative quantification of Octopamine ß receptor (OCTß-R) expression based on the 2-ΔΔCT method by quantitative real time PCR (qRT PCR). Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was used as endogenous control. Down regulation of expression of OCTß-R mRNA in the ovaries of amitraz treated ticks was observed compared to controls. Thus, the inhibition of fecundity observed in the ticks treated with amitraz can be attributed to the major structural changes and decreased expression of OCT ß receptor mRNA induced by it in the ovary.


Assuntos
Inseticidas/farmacologia , Rhipicephalus/efeitos dos fármacos , Toluidinas/farmacologia , Análise de Variância , Animais , Membrana Basal/efeitos dos fármacos , Membrana Basal/ultraestrutura , Regulação para Baixo , Feminino , Fertilidade/efeitos dos fármacos , Expressão Gênica , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Oócitos/efeitos dos fármacos , Oócitos/ultraestrutura , Ovário/anatomia & histologia , Ovário/efeitos dos fármacos , Ovário/ultraestrutura , Oviposição/efeitos dos fármacos , RNA Mensageiro/isolamento & purificação , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Amina Biogênica/agonistas , Receptores de Amina Biogênica/efeitos dos fármacos , Rhipicephalus/anatomia & histologia , Rhipicephalus/genética , Rhipicephalus/ultraestrutura , Espectrofotometria , Controle de Ácaros e Carrapatos/métodos , Vacúolos/efeitos dos fármacos , Vacúolos/ultraestrutura
11.
Arch Virol ; 164(10): 2637-2640, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31372754

RESUMO

A novel lytic Raoultella phage, RP180, was isolated and characterized. The RP180 genome has 44,851 base pairs and contains 65 putative genes, 35 of them encoding proteins whose functions were predicted based on sequence similarity to known proteins. The RP180 genome possesses a gene synteny typical of members of the subfamily Guernseyvirinae. Phylogenetic analysis of the RP180 genome and similar phage genomes revealed that phage RP180 is the first member of the genus Kagunavirus, subfamily Guernseyvirinae, that is specific for Raoultella sp. The genome of RP180 encodes a putative protein with similarity to CRISPR-like Cas4 nucleases, which belong to the pfam12705/PDDEXK_1 family. Cas4-like proteins of this family have been shown to interfere with the bacterial host type II-C CRISPR-Cas system.


Assuntos
Bacteriófagos/classificação , Bacteriófagos/isolamento & purificação , Enterobacteriaceae/virologia , Filogenia , Siphoviridae/classificação , Siphoviridae/isolamento & purificação , Bacteriólise , Bacteriófagos/genética , Genoma Viral , Microscopia Eletrônica de Transmissão , Análise de Sequência de DNA , Siphoviridae/genética , Sintenia , Proteínas Virais/genética , Vírion/ultraestrutura
12.
Arch Virol ; 164(10): 2585-2592, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31377889

RESUMO

Marbled eel reovirus (MERV) is an aquareovirus (AQRV) isolated from diseased marbled eels (Anguilla marmorata) with petechial skin hemorrhage. In this study, we propagated MERV in a cell line derived from the brain of Aequidens rivulatus and purified viral particles by using a discontinuous cesium chloride gradient. Genomic RNA sequences were obtained through next-generation sequencing. MERV, similar to most other AQRVs, showed the presence of 11 double-stranded RNA segments encoding 12 proteins; however, the genome sequence displayed very little similarity to known AQRV sequences. Furthermore, the structural proteins of MERV were most closely related to American grass carp reovirus with sequence identity values of no more than 64.89%. Phylogenetic analysis based on the sequences of structural proteins indicated that MERV shows an evolutionary history between AQRV-B and -G, which belong to the saline and freshwater environment subgroups, respectively. We also observed that MERV showed a closer relationship to orthoreoviruses based on the protein sequences of NS38 and NS73. In summary, MERV is a novel AQRV that could be classified as a member of the new proposed AQRV species "Aquareovirus H". The taxonomic assignments and evolution of AQRVs thus warrant further investigation.


Assuntos
Anguilla/virologia , Doenças dos Peixes/virologia , Infecções por Reoviridae/veterinária , Reoviridae/isolamento & purificação , Animais , Encéfalo/virologia , Linhagem Celular , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Microscopia Eletrônica de Transmissão , Filogenia , RNA de Cadeia Dupla/genética , RNA Viral/genética , Reoviridae/classificação , Reoviridae/genética , Infecções por Reoviridae/virologia , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Coloração e Rotulagem , Proteínas Virais/genética , Vírion/ultraestrutura , Cultura de Vírus
13.
Exp Parasitol ; 205: 107753, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31469986

RESUMO

Trypanosoma brucei causes human African trypanosomiasis and Nagana disease in cattle, imposing substantial medical and economic burden in sub-Saharan Africa. The current treatments have limitations, including the requirement for elaborated protocols, development of drug resistance, and they are prone to adverse side effects. In vitro screening of a library of 14 dinuclear-thiolato bridged arene ruthenium complexes, originally developed for treatment of cancer cells, resulted in the identification of 7 compounds with IC50 values ranging from 3 to 26 nM. Complex [(η6-p-MeC6H4Pri)2Ru2(µ2-SC6H4-o-Pri)3]Cl (2) (IC50 = 4 nM) and complex [(η6-p-MeC6H4Pri)2Ru2(µ2-SCH2C6H4-p-But)2(µ2-SC6H4-p-OH)]BF4(9) (IC50 = 26 nM) were chosen for further assessments. Application of complex 2 and 9 at 20 nM and 200 nM, respectively, for 4.5 h induced alterations in the trypanosome mitochondrion as evidenced by immunofluorescence employing an antibody against mitochondrial Hsp70 and Mitotracker labeling. Transmission electron microscopy of parasites taken at 2 and 4h of treatment demonstrated massive alterations in the mitochondrial ultrastructure, while other organelles and structural elements of the parasites remained unaffected. Complex 2 treated trypanosomes exhibited a distorted mitochondrial membrane, and the mitochondrial matrix was transformed into an amorphous mass with different degrees of electron densities. Complex 9 did not notably impair the integrity of the membrane, but the interior of the mitochondrion appeared either completely translucent, or was filled with filamentous structures of unknown nature. Dose- and time-dependent effects of these two compounds on the mitochondrial membrane potential were detected by tetramethylrhodamine ethyl ester assay. Thus, the mitochondrion and associated metabolic processes are an important target of dinuclear thiolato-bridged arene ruthenium complexes in T. brucei.


Assuntos
Potencial da Membrana Mitocondrial/efeitos dos fármacos , Compostos de Rutênio/farmacologia , Trypanosoma brucei brucei/efeitos dos fármacos , Tripanossomíase Africana/parasitologia , Animais , Relação Dose-Resposta a Droga , Imunofluorescência , Humanos , Concentração Inibidora 50 , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Compostos de Rutênio/química , Fatores de Tempo , Trypanosoma brucei brucei/metabolismo , Trypanosoma brucei brucei/ultraestrutura , Tripanossomíase Africana/sangue
14.
Neumol. pediátr. (En línea) ; 14(2): 76-80, jul. 2019. ilus
Artigo em Espanhol | LILACS | ID: biblio-1014992

RESUMO

Primary ciliary dyskinesia is a congenital disorder due to abnormal motile ciliary function, especially in the airway epithelium. The mucociliary clearance is impaired, producing reoccurring respiratory tract infections, usually resulting in bronchiectasis as an adult. Patients also have frequent ear and sinus infections and almost 50% of them have situs inversus. Diagnosis of primary ciliary dyskinesia is difficult because there is not a single gold standard test, resulting in the need of a multi-test approach. Until recently in our country we only had transmission electron microscopy, but nasal nitric oxide and high speed video microscopy are now available. In this article we will detail the most important clinical characteristics that make us suspect the presence of primary ciliary dyskinesia at different ages and the methods available for its diagnosis.


La discinesia ciliar primaria es una enfermedad congénita debida a una alteración del movimiento normal de los cilios, especialmente a nivel del epitelio respiratorio. Esto se traduce en una alteración del clearance mucociliar lo que predispone al paciente a tener infecciones respiratorias repetidas, terminando en la aparición de bronquiectasias en la edad adulta. También son frecuentes las infecciones repetidas de oídos y cavidades perinasales. La presencia de situs inverso puede verse en hasta en 50% de los pacientes con esta enfermedad. El diagnóstico de discinesia ciliar primaria es difícil ya que no existe un examen que sea considerado patrón de oro, por lo que se requiere la realización de distintos exámenes. En nuestro país hasta hace poco tiempo solo contábamos con la microscopía electrónica, pero recientemente se ha sumado la medición de óxido nítrico nasal y la videomicroscopía de alta velocidad. En el presente artículo se detallarán las características clínicas más importantes que hacen sospechar la presencia de DCP en las distintas edades y los métodos disponibles para su diagnóstico.


Assuntos
Humanos , Recém-Nascido , Pré-Escolar , Adulto , Síndrome de Kartagener/diagnóstico , Síndrome de Kartagener/genética , Síndrome de Kartagener/terapia , Cílios/ultraestrutura , Biópsia , Algoritmos , Testes Genéticos , Microscopia de Vídeo , Microscopia Eletrônica de Transmissão , Óxido Nítrico/análise
15.
Ecotoxicol Environ Saf ; 182: 109396, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31276888

RESUMO

We report herein the sonochemical synthesis of a lanthanum dioxide carbonate (La2O2CO3) and zinc ferrite (ZnFe2O4)-loaded reduced graphene oxide (LZF-rGO) nanoheterostructure for ultrasound (US)-assisted degradation of methyl orange (MO) from water. The MO was chosen as a model organic dye due to its toxicological and biodegradable-resistant properties. The LZF-rGO catalyst was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The results of characterizations confirmed successful synthesis of sonocatalyst. Among different removal systems, US/LZF-rGO displayed outstanding sonodegradation performance for degradation of MO. The maximum removal efficiency of 75.9% was achieved using 0.2 g/L sonocatalyst, 20 mg/L MO, and 0.71 W/cm2 US power intensity for 65 min. MO can be partially adsorbed on LZF-rGO but mostly sonodegraded by reactive radical species. The reaction conditions were optimized by investigating the effect of key operating parameters, including the sonocatalyst dosage, initial MO concentration, US power intensity, presence of inorganic salts, and use of an enhancer, on the decolorization of MO. The degradation intermediates produced from MO during the sonocatalytic process were identified by UPLC®/MS-MS, and possible mechanism and pathway for the degradation of MO in the US/LZF-rGO system were also proposed. Reusability experiments with this sonocatalyst revealed a less than 10% drop in the degradation efficiency after four adsorption-desorption cycles.


Assuntos
Corantes/química , Grafite/química , Lantânio/química , Nanoestruturas/química , Poluentes Químicos da Água/química , Carbonatos , Catálise , Compostos Férricos , Magnetismo , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Modelos Químicos , Óxidos/química , Espectroscopia Fotoeletrônica , Água , Difração de Raios X , Zinco , Compostos de Zinco , Óxido de Zinco/química
16.
Anal Bioanal Chem ; 411(21): 5437-5444, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31300858

RESUMO

To meet the need for high-throughput immunoassays, many multiplex fluorescent immunoassays have been proposed. Most of them need different kinds of fluorescent label indicators during the test. In this work, a novel indirect ELISA-inspired dual-channel fluorescent immunoassay based on 3-mercaptopropionic acid capped CdTe/ZnS quantum dots (QDs) was constructed. The ELISA wells were coated with two kinds of antigen-QD complex. When the primary antibodies were present in a sample, they mediated the binding of a secondary antibody-DNA-gold nanoparticle complex to the antigen-QD complex. Then the gold nanoparticles quenched the fluorescence of the QDs and a decrease in fluorescence intensity was observed. Thus, the amount of primary antibody could be estimated from the decrease of fluorescence intensity. Owing to the wide absorption range and the relatively narrow emission band of the QDs, the dual-channel fluorescent immunoassay system could work at the same excitation wavelength and the emission wavelengths of each channel had no interference. As a result, two different kinds of primary antibody could be detected at the same time in one ELISA well, which simplified the operation and greatly improved the efficiency. Besides, only one type of secondary antibody needs to be added to the prepared microtiter plates, which further simplified the operation during the detection procedure. This dual-channel fluorescent immunoassay system will provide new insights into high-throughput immunodetection. Graphical abstract.


Assuntos
Compostos de Cádmio/química , Ensaio de Imunoadsorção Enzimática/métodos , Imunofluorescência/métodos , Pontos Quânticos , Sulfetos/química , Telúrio/química , Compostos de Zinco/química , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão
17.
J Insect Sci ; 19(4)2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31268547

RESUMO

In recent years, we found that Hishimonus lamellatus Cai et Kuoh is a potential vector of jujube witches'-broom phytoplasma. However, little is known about the anatomy and histology of this leafhopper. Here, we examined histology and ultrastructure of the digestive system of H. lamellatus, both by dissecting and by semi- and ultrathin sectioning techniques. We found that the H. lamellatus digestive tract consists of an esophagus, a filter chamber, a conical midgut and midgut loop, Malpighian tubules, an ileum, and a rectum. Furthermore, both the basal region of the filter chamber epithelium and the apical surface of the midgut epithelium have developed microvilli. We also identify the perimicrovillar membrane, which ensheaths the microvilli of midgut loop enterocyte, and the flame-like luminal membrane, which covers the microvilli of the conical midgut epithelium. In addition, H. lamellatus has the principal and accessory salivary glands. Our observations also showed that the endoplasmic reticulum, mitochondria, and secretory granules were all highly abundant in the secretory cells of the principal salivary glands, while the accessory glands consist of only one ovate or elbow-like acinus. We also briefly contrast the structure of the gut of H. lamellatus with those of other leafhopper species. These results intend to offer help for the future study on the histological and subcellular levels of phytopathogen-leafhopper relationships, including transmission barriers and the binding sites of pathogens and other microorganisms within their leafhopper vectors.


Assuntos
Hemípteros/ultraestrutura , Túbulos de Malpighi/ultraestrutura , Animais , Trato Gastrointestinal/ultraestrutura , Microscopia Eletrônica de Transmissão , Glândulas Salivares/ultraestrutura
18.
J Photochem Photobiol B ; 197: 111547, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31325773

RESUMO

In the present work, Fe3O4 nanoparticles with superparamagnetic properties were prepared and capped by using Chitosan. The synthesized NPs were studied by using transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy. Average particle size and surface charge of the synthesized NPs were characterized by using Malvern Zetasizer instrument. TEM images showed the morphology and size distribution of uncoated Fe3O4 NPs, exhibiting the uniform sized NPS with an average particle size of about 10 nm. Vibrating Scanning Magnetometry (VSM) experiments, showed the superparamagnetic nature of the prepared nanoparticles. Fe3O4 NPs showed ferromagnetic magnetization which is very sensitive towards the sample's nanostructure. The results of paramagnetic studies exhibited the substantial reduction in paramagnetic behavior after Chitosan coating but sufficient for responding in magnetic field. Further, the in-vitro ability of the Chitosan coated Fe3O4 NPs as contrast agents in efficient Ultra sound/Magnetic resonance (US/MR) imaging was investigated. These findings demonstrated that the Chitosan coated super para magnetic iron oxide nanoparticles (SPION) have reported significant contrast-enhanced imaging potential for dual-mode US/MR imaging. Hence, the prepared Chitosan coated SPION composites administration serve as potential guide in the diagnosis and treatment of cancers.


Assuntos
Óxido Ferroso-Férrico/química , Imagem por Ressonância Magnética , Nanopartículas de Magnetita/química , Neoplasias/diagnóstico , Ultrassonografia , Quitosana/química , Humanos , Microscopia Eletrônica de Transmissão , Neoplasias/diagnóstico por imagem , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
19.
J Photochem Photobiol B ; 197: 111536, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31326846

RESUMO

The latent utilization of biomaterials that are osteo-conducive in the advancement of healing bone fracture has fascinated extensive consideration. This work includes the synthesis of silver nanoparticles (AgNPs) with the help of a Bauhinia acuminate plant flower extract through an ecofriendly synthetic process without any use of harmful reductants. In the fabrication of AgNPs, Bauhinia acuminate plant flower extract bio constituents acts as both stabilizing and reducing agent. The studies of Fourier transform infrared (FTIR) and X-ray diffraction (XRD) techniques confirmed the formation of AgNPS. TEM images revealed that AgNPs are uniform with average particle size of 17 nm. Further, this work explored if silver nanoparticles (AgNPs) might endorse the osteogenesis and proliferation of mesenchymal stem cells (MSCs) and advance the curing of bone fractures. We also exhibited that the prepared AgNPs could promote the in -vitro osteogenic differentiation and proliferation of MSCs'. Also, the prepared AgNps could stimulate the proliferation of mMSCs at specific concentrations of 6-20 µM. Further, cell viability studies showed that AgNPs exhibited no reduction in mouse mesenchymal stem cell viability at <4 µM. Further, these results indicated the induction effects of AgNPs on osteogenic differentiation and proliferation on MSCs, as well as the advancement of meniscus injury healing.


Assuntos
Bauhinia/química , Nanopartículas Metálicas/química , Osteogênese , Extratos Vegetais/química , Prata/química , Animais , Bauhinia/metabolismo , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Flores/química , Flores/metabolismo , Consolidação da Fratura/efeitos dos fármacos , Química Verde , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Nanopartículas Metálicas/toxicidade , Camundongos , Microscopia Eletrônica de Transmissão , Osteogênese/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier
20.
Anal Bioanal Chem ; 411(21): 5593-5603, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31289896

RESUMO

A novel SBA-15-based fluorescent sensor, SBA-PI: mesoporous SBA-15 structure modified with iminostilbene groups, was designed, synthesized, and characterized by Fourier transform-infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA), low-angle X-ray diffraction techniques (low-angle XRD), and N2 adsorption-desorption techniques. The SBA-PI as a sensor with a selective behavior for detection of Cu2+ comprises iminostilbene carbonyl as the fluorophore group. The SBA-PI sensor displays an excellent fluorescence response in aqueous solutions and the fluorescence intensity quenches remarkably upon addition of Cu2+. Other common interfering ions even at high concentration ratio showed either no or very small changes in the fluorescence intensity of SBA-PI in the absence of Cu2+. A limit of detection of 8.7 × 10-9 M for Cu2+ indicated that this fluorescence sensor has a high sensitivity and selectivity toward the target copper (II) ion. The fabricated Cu2+ sensor was successfully applied for the determination of the Cu2+ in human blood samples without any significant interference. With the selective analysis of Cu2+ ions down to 0.9 nM in blood, the sensor is a promising and a novel detection candidate for Cu2+ and can be applied in the clinical laboratory. A reversibility and accuracy in the fluorescence behavior of the sensor was found in the presence of I¯ that was described as a masking agent for Cu2+. Graphical abstract.


Assuntos
Cobre/sangue , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Oligoelementos/sangue , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Difração de Pó , Espectrometria por Raios X , Termogravimetria
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