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1.
Sci Rep ; 14(1): 15289, 2024 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961137

RESUMO

The limited availability of antivirals for new highly pathogenic strains of virus has become a serious public health. Therefore, news products against these pathogens has become an urgent necessity. Among the multiple sources for news antibiotics and antivirals, insect exudates or their products has become an increasingly frequent option. Insects emerged 350 million years ago and have showed a high adaptability and resistance to the most varied biomes. Their survival for so long, in such different environments, is an indication that they have a very efficient protection against environmental infections, despite not having a developed immune system like mammals. Since the ancient civilizations, the products obtained from the bee have been of great pharmacological importance, being used as antimicrobial, anti-inflammatory, antitumor and several other functions. Investigations of biological activity of propolis have been carried out, mainly in the species Apis mellifera, and its product have showed activity against some important viruses. However, for the Meliponini species, known as stingless bees, there are few studies, either on their chemical composition or on their biological activities. The importance of studying these bees is because they come from regions with native forests, and therefore with many species of plants not yet studied, in addition to which they are regions still free of pesticides, which guarantees a greater fidelity of the obtained data. Previous studies by our group with crude hydroalcoholic extract of propolis demonstrated an intense antiviral activity against Herpes, influenza, and rubella viruses. In this work, we chose to use aqueous extracts, which eliminates the presence of other compounds besides those originally present in propolis, in addition to extracting substances different from those obtained in alcoholic extracts. Therefore, this study aimed to identify, isolate and characterize compounds with antiviral effects from aqueous propolis extracts from Scaptotrigona aff postica, in emerging viruses such as zicavirus, chikungunya, and mayaro virus. The evaluation of the antiviral activity of the crude and purified material was performed by reducing infectious foci in VERO cell cultures. The results obtained with crude propolis, indicate a high reduction of zica virus (64×) and mayaro (128×) when was used 10% v/v of propolis. The reduction of chikungunya virus was of 256 fold, even when was used 5% v/v of propolis. The chemical characterization of the compounds present in the extracts was performed by high-pressure liquid chromatography. Through the purification of propolis by HPLC and mass spectrometry, it was possible to identify and isolate a peak with antiviral activity. This substance showed activity against all viruses tested. When purified fraction was used, the reduction observed was of 16 fold for zicavirus, 32 fold for mayaro virus and 512 fold for chikungunya virus. Likewise, it was observed that the antiviral response was concentration dependent, being more intense when propolis was added 2 h after the viral infection. Now we are carrying out the chemical characterization of the purified compounds that showed antiviral action.


Assuntos
Antivirais , Própole , Própole/farmacologia , Própole/química , Animais , Antivirais/farmacologia , Antivirais/química , Abelhas , Vírus Chikungunya/efeitos dos fármacos , Chlorocebus aethiops , Células Vero
2.
Folia Morphol (Warsz) ; 79(4): 805-810, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32020581

RESUMO

BACKGROUND: Didelphis aurita is a marsupial with wide distribution in the South American continent and highly adapted to urban centres. The objective of this study was to describe the measurements and skeletopy of the kidneys and renal vascularisation of this species. MATERIALS AND METHODS: With this aim, 29 cadavers (14 males and 15 females) of D. aurita collected on highways were analysed. The rostrum-sacral length of specimens, kidney measurements (length, width and thickness) and the length of the renal vessels were measured and the renal skeletopy registered. RESULTS: In the right kidney, average length, width, thickness and ellipsoid volume were 28.6 ± 5.0 mm, 15.6 ± 2.9 mm, 12.8 ± 3.0 mm and 3.3 ± 2.4 cm3, respectively; in the left kidney, 31.0 ± 3.8 mm, 14.5 ± 3.6 mm, 12.6 ± 2.6 mm and 3.2 ± 2.2 cm3, respectively. There was no significant difference in the comparison of averages of renal dimensions between sexes and between antimeres. The right renal artery (13.2 ± 2.6 mm) was significantly longer (p < 0.01) than the left renal artery (10.7 ± 2.3 mm). In contrast, the left renal vein (13.9 ± 3.5 mm) was longer (p < 0.01) than the right renal vein (7.0 ± 2.3 mm). The skeletopy of the right kidney predominated between T13-L1 in 58.6% of the cases and the skeletopy of the left kidney between L1-L3 in 41.4%. The average length of the kidneys corresponded to 6% to 8% of the rostrum-sacral length of the specimens. CONCLUSIONS: The data of the present study characterised the measurements and topography of kidneys and renal vessels in D. aurita and can support the interpretation of clinical, experimental and pathological findings in this species.


Assuntos
Didelphis , Animais , Feminino , Rim , Masculino
3.
LAES, HAES, jan. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4183

RESUMO

Parasitism caused by protozoa and helminths is a serious public health problem, affecting millions of individuals worldwide, especially in underdeveloped and developing countries. From this perspective, a parasitological survey was conducted in 37 cities in the interior of the state of São Paulo. This study focused mainly on old places such as schools and rural and urban health units in the interior of the State of São Paulo between 1957 and 1986. The objective of this study was to conduct a comprehensive survey on the data found to diagnose the occurrence of parasitic diseases in the city. Population at that time, according to their rural and urban origin, age and gender. Thus, the proposal is to make the generated data available to all interested parties in an organized and systematized manner and to discuss the reality faced by the population regarding the current public policies in Brazil relating the sanitary conditions with the occurrence of endoparasites. According to the survey conducted in the municipalities studied, 274,487 occurrences of individuals positive for endoparasites were obtained from 391,633 samples collected. The highest frequency was found in children aged 1 to 10 years with 146,090 cases, accounting for 37,302% of the infected population. The percentage of parasitized individuals decreases with increasing age.


Os quadros de parasitismos causados por protozoários e helmintos constituem sérios problemas de saúde pública, por afetarem milhões de indivíduos em todo o mundo, sobretudo, nos países subdesenvolvidos e em desenvolvimento. Sob esta perspectiva foi realizado um levantamento parasitológico em 37 cidades do interior do Estado de São Paulo. Este estudo contemplou principalmente antigos locais como as escolas e unidades de saúde rurais e urbanas do interior do Estado de São Paulo entre os anos de 1957 e 1986. O objetivo deste trabalho foi realizar um levantamento abrangente nos dados encontrados para diagnosticar a ocorrência de parasitoses na população da época, segundo sua origem rural e urbana, a faixa etária e o gênero. Dessa forma, a proposta é tornar os dados gerados disponíveis a todos os interessados de forma organizada e sistematizada e discutir a realidade enfrentada pela população frente às políticas públicas vigentes no Brasil relacionando as condições sanitárias com a ocorrência de endoparasitoses. Segundo o levantamento realizado nos municípios estudados, obteve-se 274.487 ocorrências de indivíduos positivos para endoparasitas a partir de 391.633 amostras coletadas. A maior frequência foi encontrada em crianças de 1 a 10 anos com 146.090 casos, sendo estes responsáveis por 37.302% da população infectada. A porcentagem de indivíduos parasitados diminui de acordo com o aumento da idade.

4.
J Mech Behav Biomed Mater ; 60: 547-556, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27058002

RESUMO

OBJECTIVES: The purpose of this study was to evaluate the shear bond strength of veneering feldspathic porcelain to zirconia substrates modified by CNC-milling process or by coating zirconia with a composite interlayer. METHODS: Four types of zirconia-porcelain interface configurations were tested: RZ - porcelain bonded to rough zirconia substrate (n=16); PZ - porcelain bonded to zirconia substrate with surface holes (n=16); RZI - application of a composite interlayer between the veneering porcelain and the rough zirconia substrate (n=16); PZI - application of a composite interlayer between the porcelain and the zirconia substrate treated by CNC-milling (n=16). The composite interlayer was composed of zirconia particles reinforced porcelain (30%, vol%). The mechanical properties of the ceramic composite have been determined. The shear bond strength test was performed at 0.5mm/min using a universal testing machine. The interfaces of fractured and untested specimens were examined by FEG-SEM/EDS. Data was analyzed with Shapiro-Wilk test to test the assumption of normality. The one-way ANOVA followed by Tukey HSD multiple comparison test was used to compare shear bond strength results (α=0.05). RESULTS: The shear bond strength of PZ (100±15MPa) and RZI (96±11MPa) specimens were higher than that recorded for RZ (control group) specimens (89±15MPa), although not significantly (p>0.05). The highest shear bond strength values were recorded for PZI specimens (138±19MPa), yielding a significant improvement of 55% relative to RZ specimens (p<0.05). SIGNIFICANCE: This study shows that it is possible to highly enhance the zirconia-porcelain bond strength - even by ~55% - by combining surface holes in zirconia frameworks and the application of a proper ceramic composite interlayer.


Assuntos
Porcelana Dentária , Facetas Dentárias , Zircônio , Colagem Dentária , Análise do Estresse Dentário , Humanos , Teste de Materiais , Resistência ao Cisalhamento , Propriedades de Superfície
5.
J Mech Behav Biomed Mater ; 50: 123-30, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26122789

RESUMO

The aim of this work was to study, using the finite element method (FEM), the distribution of thermal residual stresses arising in metal-ceramic dental restorations after cooling from the processing temperature. Three different interface configurations were studied: with conventional sharp transition; one with a 50% metal-50% ceramic interlayer; and one with a compositionally functionally gradated material (FGM) interlayer. The FE analysis was performed based on experimental data obtained from Dynamic Mechanical Analysis (DMA) and Dilatometry (DIL) studies of the monolithic materials and metal/ceramic composites. Results have shown significant benefits of using the 50% metal-50% ceramic interlayer and the FGM interlayer over the conventional sharp transition interface configuration in reduction of the thermal residual stress and improvement of stress profiles. Maximum stresses magnitudes were reduced by 10% for the crowns with 50% metal-50% ceramic interlayer and by 20% with FGM interlayer. The reduction in stress magnitude and smoothness of the stress distribution profile due to the gradated architectures might explain the improved behavior of these novel dental restorative systems relative to the conventional one, demonstrated by in-vitro studies already reported in literature.


Assuntos
Análise de Elementos Finitos , Teste de Materiais , Ligas Metalo-Cerâmicas , Estresse Mecânico , Temperatura , Módulo de Elasticidade
6.
Mater Sci Eng C Mater Biol Appl ; 39: 29-34, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24863193

RESUMO

This study presents the development of natural rubber-Ca/P blends, as promising candidates for biomedical purposes. The specific objective was the incorporation of Ca/P into a natural rubber polymeric matrix. Ca/P crystalline phases were synthesized by the sol-gel method and the polymeric matrices were produced using natural rubber extracted from latex of the Hevea brasiliensis. The shape and size of natural rubber particles present in the NR membrane, as well as, the way the Ca/P powder grains aggregate in the polymeric matrix were investigated, giving information about the interactions between the Ca/P and the natural rubber particles. Confocal fluorescence scanning microscopy measurements allowed us to propose a structure where the Ca/P grains are surrounded by natural rubber particles. This structure may mediate Ca(2+) release for tissue regeneration. The system investigated may open new horizons for development of a bandage which provides the controlled-release of biomaterials.


Assuntos
Tecnologia Biomédica/instrumentação , Borracha/química , Fosfatos de Cálcio/síntese química , Hevea/química , Látex/química , Microscopia Confocal , Extratos Vegetais/química , Proteínas/química
7.
J Mech Behav Biomed Mater ; 30: 103-10, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24269945

RESUMO

In this study, mechanical and thermal properties of CoCrMo-porcelain composites for dental restorations have been evaluated. These metal-ceramic composites were produced by powder metallurgy and hot pressing techniques from the mixtures of metal and ceramic powders with different volume fractions. Young's moduli and the coefficient of thermal expansion of materials were evaluated by dynamic mechanical analysis (DMA) and dilatometry (DIL) tests, respectively. The strength in flexion and shear was measured with a universal test machine and hardness with a respective tester. The microstructures and fracture surfaces were inspected by the means of optical microscopy and Scanning Electron Microscopy/Energy Dispersive Spectroscopy (SEM/EDS). Shear strength, Flexural strength and Young' moduli of ceramic and metal-matrix composites were found to increase with higher metal particles content. The DMA tests performed at different frequencies showed no frequency-dependent features of the materials studied, indicating no viscoelastic behavior. The fracture surfaces analysis suggests the load-transfer mechanism be possibly responsible for this behavior, as the differences in CTE are low enough to cause significant thermal stresses in these materials. The results might be included in a materials properties database for further use for design and optimization of dental restorations.


Assuntos
Porcelana Dentária/química , Prótese Dentária , Temperatura Alta , Fenômenos Mecânicos , Vitálio/química , Módulo de Elasticidade , Teste de Materiais , Resistência ao Cisalhamento , Propriedades de Superfície
9.
Protein J ; 29(3): 188-94, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20349205

RESUMO

A beta-N-Acetylhexosaminidase (EC 3.2.1.52) was purified from hepatic extracts of Sotalia fluviatilis, order Cetacea. The protein was purified by using ammonium sulfate fractionation and four subsequent chromatographies (Biogel A 1.5 m, Chitin, Deae-Biogel and hydroxyapatite resins). After these purification steps, the enzyme was purified 380.5-fold with an 8.4% yield. The molecular mass (10 kDa) was estimated by SDS-PAGE and MALDI-TOF analysis. A Km of 2.72 mM and Vmax 9.5 x 10(-6) micromol/(min x mg) were found for this enzyme, determined by p-nitrophenyl-beta-D: -hexosaminide substrate digestion. Optimal pH and temperature for beta-N-Acetylhexosaminidase activity were 5.0 and 60 degrees C, respectively. Enzyme activity was inhibited by sodium selenate (Na(2)SeO(4)), mercuric chloride (HgCl(2)) and sodium dodecyl sulfate (C(12)H(25)SO(4)Na), and activated by zinc, calcium, barium and lithium ions. Characterization of the beta-N-Acetylhexosaminidase in Sotalia fluviatilis can be a basis for physiological studies in this species.


Assuntos
Golfinhos/metabolismo , Fígado/enzimologia , beta-N-Acetil-Hexosaminidases/isolamento & purificação , Animais , Carboidratos , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Cinética , Fígado/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Temperatura , beta-N-Acetil-Hexosaminidases/química , beta-N-Acetil-Hexosaminidases/metabolismo
10.
J. bras. ginecol ; 104(10): 373-6, out. 1994. ilus, tab
Artigo em Português | LILACS | ID: lil-166885

RESUMO

As vantagens da drenagem vesical suprapúbica sobre a sonda transuretral reside no menor índice de infecçåo urinária e traumatismo uretral. Este estudo avaliou dados de 50 pacientes submetidas a colpoperineoplastia com drenagemvesical suprapúbica comparativamente a um grupo de controle de outras 50 pacientes submetidas ao mesmo procedimento cirúrgico e com drenagem trasuretral, no període de fevereiro de 1991 a maio de 1993, no serviço de ginecologia da Universidade Federal do Paraná. Na primeira micçåo espontânea do grupo com sondagem suprapúbica, 42,9 por cento das pacientes tiveram volume residual menor que 50ml e esta ocorreu 11,2 horas antes que no grupo controle com sonda transuretral. A permanência hospitalar foi menor (3,9 dias frente a 4,5 dias); a incidência de infecçåo urinária foi claramente menor frente ao grupo controle (15 por cento para 20,5 por cento). Apenas 20,4 por cento apresentaram dor e desconforto com a sonda suprapúbica mostrando uma boa tolerância. A hematúria tanto macro como microscópica ocorreu com maior freqüência no grupo com sonda suprapúbica. Observamos apens dois casos de complicaçåo que exigiram a retirada imediata da sonda. O custo elevado da sonda suprapúbica mostrou ser compensado pela precocidade da alta hospitalar e morbidade infecciosa reduzida


Assuntos
Humanos , Feminino , Cateteres de Demora/estatística & dados numéricos , Drenagem/estatística & dados numéricos , Infecções Urinárias/prevenção & controle , Períneo/cirurgia , Cirurgia Plástica , Vagina/cirurgia
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