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1.
Arq Neuropsiquiatr ; 82(1): 1-6, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38286430

ABSTRACT

BACKGROUND: Chikungunya is a mosquito-borne disease caused by the chikungunya virus (CHIKV) and can lead to neurological complications in severe cases. OBJECTIVE: This study examined neuroimaging patterns in chikungunya cases during two outbreaks in Brazil to identify specific patterns for diagnosis and treatment of neuro-chikungunya. METHODS: Eight patients with confirmed chikungunya and neurological involvement were included. Clinical examinations and MRI scans were performed, and findings were analyzed by neuroradiologists. Data on age, sex, neurological symptoms, diagnostic tests, MRI findings, and clinical outcomes were recorded. RESULTS: Patients showed different neuroimaging patterns. Six patients exhibited a "clock dial pattern" with hyperintense dotted lesions in the spinal cord periphery. One patient had thickening and enhancement of anterior nerve roots. Brain MRI revealed multiple hyperintense lesions in the white matter, particularly in the medulla oblongata, in six patients. One patient had a normal brain MRI. CONCLUSION: The "clock dial pattern" observed in spinal cord MRI may be indicative of chikungunya-related nervous system lesions. Isolated involvement of spinal cord white matter in chikungunya can help differentiate it from other viral infections. Additionally, distinct brainstem involvement in chikungunya-associated encephalitis, particularly in the rostral region, sets it apart from other arboviral infections. Recognizing these neuroimaging patterns can contribute to early diagnosis and appropriate management of neuro-chikungunya.


ANTECEDENTES: A chikungunya é uma doença transmitida por mosquitos causada pelo vírus chikungunya (CHIKV) e pode levar a complicações neurológicas em casos graves. OBJETIVO: Este estudo examinou padrões de neuroimagem em casos de chikungunya durante dois surtos no Brasil para identificar padrões específicos para o diagnóstico e tratamento de neurochikungunya. MéTODOS: Oito pacientes com chikungunya confirmada e envolvimento neurológico foram incluídos. Exames clínicos e ressonâncias magnéticas (RM) foram realizados, e os achados foram analisados por neurorradiologistas. Dados sobre idade, sexo, sintomas neurológicos, testes diagnósticos, achados de RM e desfechos clínicos foram registrados. RESULTADOS: Os pacientes apresentaram diferentes padrões de neuroimagem. Seis pacientes apresentaram um "padrão de mostrador de relógio" com lesões pontilhadas hiperintensas na periferia da medula espinhal. Um paciente apresentou espessamento e realce das raízes nervosas anteriores. A RM do cérebro revelou múltiplas lesões hiperintensas na substância branca, especialmente no bulbo em seis pacientes. Um paciente apresentou uma RM cerebral normal. CONCLUSãO: O "padrão de mostrador de relógio" observado na RM da medula espinhal pode ser indicativo de lesões do sistema nervoso relacionadas à chikungunya. O envolvimento isolado da substância branca da medula espinhal na chikungunya pode ajudar a diferenciá-la de outras infecções virais. Além disso, o envolvimento distinto do tronco cerebral na encefalite associada à chikungunya, especialmente na região rostral, a distingue de outras infecções por arbovírus. O reconhecimento desses padrões de neuroimagem pode contribuir para o diagnóstico precoce e manejo adequado da neurochikungunya.


Subject(s)
Chikungunya Fever , Chikungunya virus , Nervous System Diseases , Animals , Humans , Chikungunya Fever/complications , Chikungunya Fever/diagnostic imaging , Nervous System Diseases/complications , Magnetic Resonance Imaging , Neuroimaging
2.
Arq. neuropsiquiatr ; 82(1): s00441779033, 2024. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1533832

ABSTRACT

Abstract Background Chikungunya is a mosquito-borne disease caused by the chikungunya virus (CHIKV) and can lead to neurological complications in severe cases. Objective This study examined neuroimaging patterns in chikungunya cases during two outbreaks in Brazil to identify specific patterns for diagnosis and treatment of neuro-chikungunya. Methods Eight patients with confirmed chikungunya and neurological involvement were included. Clinical examinations and MRI scans were performed, and findings were analyzed by neuroradiologists. Data on age, sex, neurological symptoms, diagnostic tests, MRI findings, and clinical outcomes were recorded. Results Patients showed different neuroimaging patterns. Six patients exhibited a "clock dial pattern" with hyperintense dotted lesions in the spinal cord periphery. One patient had thickening and enhancement of anterior nerve roots. Brain MRI revealed multiple hyperintense lesions in the white matter, particularly in the medulla oblongata, in six patients. One patient had a normal brain MRI. Conclusion The "clock dial pattern" observed in spinal cord MRI may be indicative of chikungunya-related nervous system lesions. Isolated involvement of spinal cord white matter in chikungunya can help differentiate it from other viral infections. Additionally, distinct brainstem involvement in chikungunya-associated encephalitis, particularly in the rostral region, sets it apart from other arboviral infections. Recognizing these neuroimaging patterns can contribute to early diagnosis and appropriate management of neuro-chikungunya.


Resumo Antecedentes A chikungunya é uma doença transmitida por mosquitos causada pelo vírus chikungunya (CHIKV) e pode levar a complicações neurológicas em casos graves. Objetivo Este estudo examinou padrões de neuroimagem em casos de chikungunya durante dois surtos no Brasil para identificar padrões específicos para o diagnóstico e tratamento de neurochikungunya. Métodos Oito pacientes com chikungunya confirmada e envolvimento neurológico foram incluídos. Exames clínicos e ressonâncias magnéticas (RM) foram realizados, e os achados foram analisados por neurorradiologistas. Dados sobre idade, sexo, sintomas neurológicos, testes diagnósticos, achados de RM e desfechos clínicos foram registrados. Resultados Os pacientes apresentaram diferentes padrões de neuroimagem. Seis pacientes apresentaram um "padrão de mostrador de relógio" com lesões pontilhadas hiperintensas na periferia da medula espinhal. Um paciente apresentou espessamento e realce das raízes nervosas anteriores. A RM do cérebro revelou múltiplas lesões hiperintensas na substância branca, especialmente no bulbo em seis pacientes. Um paciente apresentou uma RM cerebral normal. Conclusão O "padrão de mostrador de relógio" observado na RM da medula espinhal pode ser indicativo de lesões do sistema nervoso relacionadas à chikungunya. O envolvimento isolado da substância branca da medula espinhal na chikungunya pode ajudar a diferenciá-la de outras infecções virais. Além disso, o envolvimento distinto do tronco cerebral na encefalite associada à chikungunya, especialmente na região rostral, a distingue de outras infecções por arbovírus. O reconhecimento desses padrões de neuroimagem pode contribuir para o diagnóstico precoce e manejo adequado da neurochikungunya.

3.
Int J Prosthodont ; 36(5): 650, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-36445220

ABSTRACT

PURPOSE: To evaluate different protocols for recementation of dislodged glass fiber posts (GFPs). MATERIALS AND METHODS: The root canals of 50 bovine incisors were prepared to receive GFPs that were conditioned with 24% hydrogen peroxide, silanized, and cemented with a self-adhesive resin cement. After light curing, the specimens were submitted to a pullout test. The dislodged GPFs were distributed into five experimental groups (n = 10) for the recementation surface treatment: NT = no treatment; SI = silane; ET = 92.8% ethanol/silane; HP = 24% hydrogen peroxide/silane; and AL = airborne-particle abrasion (50 µm alumina)/silane. The GFPs were recemented with the same self-adhesive resin cement, and specimens were submiLed to a second pullout test. Data were analyzed with Student t test and one-way ANOVA (α = .05). RESULTS: For all groups, the recementation bond strength was higher than the strength obtained after the first cementa4on (P < .05). There were no statistical differences among the experimental recementation protocols (P = .096). CONCLUSIONS: All recementation protocols might be reliably applied because they led to higher bond strength than the first cementation. Int J Prosthodont 2023;36:e74-e87.


Subject(s)
Dental Bonding , Post and Core Technique , Animals , Cattle , Resin Cements/chemistry , Silanes/chemistry , Hydrogen Peroxide , Surface Properties , Glass/chemistry , Materials Testing , Dentin , Dental Stress Analysis
4.
Braz J Microbiol ; 52(3): 1287-1302, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34002353

ABSTRACT

There is increasing evidence showing positive association between changes in oral microbiome and the occurrence of oral squamous cell carcinoma (OSCC). Alcohol- and nicotine-related products can induce microbial changes but are still unknown if these changes are related to cancerous lesion sites. In an attempt to understand how these changes can influence the OSCC development and maintenance, the aim of this study was to investigate the oral microbiome linked with OSCC as well as to identify functional signatures and associate them with healthy or precancerous and cancerous sites. Our group used data of oral microbiomes available in public repositories. The analysis included data of oral microbiomes from electronic cigarette users, alcohol consumers, and precancerous and OSCC samples. An R-based pipeline was used for taxonomic and functional prediction analysis. The Streptococcus spp. genus was the main class identified in the healthy group. Haemophilus spp. predominated in precancerous lesions. OSCC samples revealed a higher relative abundance compared with the other groups, represented by an increased proportion of Fusobacterium spp., Prevotella spp., Haemophilus spp., and Campylobacter spp. Venn diagram analysis showed 52 genera exclusive of OSCC samples. Both precancerous and OSCC samples seemed to present a specific associated functional pattern. They were menaquinone-dependent protoporphyrinogen oxidase pattern enhanced in the former and both 3',5'-cyclic-nucleotide phosphodiesterase (purine metabolism) and iron(III) transport system ATP-binding protein enhanced in the latter. We conclude that although precancerous and OSCC samples present some differences on microbial profile, both microbiomes act as "iron chelators-like" potentially contributing to tumor growth.


Subject(s)
Carcinoma, Squamous Cell , Iron/metabolism , Microbiota , Mouth Neoplasms , Tumor Microenvironment , Alcohol Drinking , Carcinoma, Squamous Cell/microbiology , Electronic Nicotine Delivery Systems , Ferric Compounds/metabolism , Humans , Mouth Neoplasms/microbiology , Precancerous Conditions/microbiology
5.
J Appl Oral Sci ; 28: e20190499, 2020.
Article in English | MEDLINE | ID: mdl-32348441

ABSTRACT

Enzymatic degradation of the hybrid layer can be accelerated by the activation of dentin metalloproteinases (MMP) during the bonding procedure. MMP inhibitors may be used to contain this process. Objective To evaluate the degree of conversion (DC%), dentin bond strength (µTBS) (immediate and after 1 year of storage in water), and nanoleakage of an experimental (EXP) and a commercial (SB) adhesive system, containing different concentrations of the MMP inhibitor GM1489: 0, 1 µM, 5 µM and 10 µM. Methodology DC% was evaluated by FT-IR spectroscopy. Dentin bond strength was evaluated by µTBS test. Half of beams were submitted to the µTBS test after 24 h and the other half, after storage for 1 year. From each tooth and storage time, 2 beams were reserved for nanoleakage testing. Data were analyzed using ANOVA and Tukey's test to compare means (α=0.05). Results All adhesive systems maintained the µTBS after 1 year of storage. Groups with higher concentrations of inhibitor (5 µM and 10 µM) showed higher µTBS values than groups without inhibitor or with 1 µM. The nanoleakage values of all groups showed no increase after 1 year of storage and values were similar for SB and EXP groups, in both storage periods. The inhibitor did not affect the DC% of the EXP groups, but the SB5 and SB10 groups showed higher DC% values than those of SB0 and SB1. Conclusions The incorporation of GM1489 in the adhesive systems had no detrimental effect on DC%. The concentrations of 5 µM GM1489 for SB and 5 µM or 10 µM for EXP provided higher µTBS than groups without GM1489, in the evaluation after 1 year of storage; whereas the concentration of inhibitor did not affect adhesive systems nanoleakage.


Subject(s)
Dental Cements/chemistry , Dentin/chemistry , Matrix Metalloproteinase Inhibitors/chemistry , Methacrylates/chemistry , Polyethylene Glycols/chemistry , Polymethacrylic Acids/chemistry , Analysis of Variance , Dental Bonding/methods , Dental Etching/methods , Dental Leakage , Dentin/drug effects , Humans , Materials Testing , Reference Values , Reproducibility of Results , Spectroscopy, Fourier Transform Infrared , Statistics, Nonparametric , Surface Properties , Tensile Strength , Time Factors
6.
J. appl. oral sci ; 28: e20190499, 2020. tab, graf
Article in English | LILACS, BBO - Dentistry | ID: biblio-1101251

ABSTRACT

Abstract Enzymatic degradation of the hybrid layer can be accelerated by the activation of dentin metalloproteinases (MMP) during the bonding procedure. MMP inhibitors may be used to contain this process. Objective To evaluate the degree of conversion (DC%), dentin bond strength (µTBS) (immediate and after 1 year of storage in water), and nanoleakage of an experimental (EXP) and a commercial (SB) adhesive system, containing different concentrations of the MMP inhibitor GM1489: 0, 1 µM, 5 µM and 10 µM. Methodology DC% was evaluated by FT-IR spectroscopy. Dentin bond strength was evaluated by µTBS test. Half of beams were submitted to the µTBS test after 24 h and the other half, after storage for 1 year. From each tooth and storage time, 2 beams were reserved for nanoleakage testing. Data were analyzed using ANOVA and Tukey's test to compare means (α=0.05). Results All adhesive systems maintained the µTBS after 1 year of storage. Groups with higher concentrations of inhibitor (5 µM and 10 µM) showed higher µTBS values than groups without inhibitor or with 1 µM. The nanoleakage values of all groups showed no increase after 1 year of storage and values were similar for SB and EXP groups, in both storage periods. The inhibitor did not affect the DC% of the EXP groups, but the SB5 and SB10 groups showed higher DC% values than those of SB0 and SB1. Conclusions The incorporation of GM1489 in the adhesive systems had no detrimental effect on DC%. The concentrations of 5 µM GM1489 for SB and 5 µM or 10 µM for EXP provided higher μTBS than groups without GM1489, in the evaluation after 1 year of storage; whereas the concentration of inhibitor did not affect adhesive systems nanoleakage.


Subject(s)
Humans , Polyethylene Glycols/chemistry , Polymethacrylic Acids/chemistry , Dental Cements/chemistry , Dentin/chemistry , Matrix Metalloproteinase Inhibitors/chemistry , Methacrylates/chemistry , Reference Values , Surface Properties , Tensile Strength , Time Factors , Materials Testing , Reproducibility of Results , Analysis of Variance , Dental Bonding/methods , Spectroscopy, Fourier Transform Infrared , Statistics, Nonparametric , Dental Leakage , Dentin/drug effects , Dental Etching/methods
7.
J Prosthet Dent ; 121(3): 485-491, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30409721

ABSTRACT

STATEMENT OF PROBLEM: Nonthermal argon plasma may increase the surface energy of yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) dental ceramics. However, studies that evaluated the effect of increased plasma treatment times on the bond strength of resin cements to Y-TZP ceramics are lacking. PURPOSE: The purpose of this in vitro study was to evaluate the effect of different nonthermal argon plasma (NTAP) treatment times on the surface energy and bond strength of a self-adhesive resin cement to Y-TZP ceramic. MATERIAL AND METHODS: Forty-eighty Y-TZP plates were divided into 2 groups (n=24): as-sintered (AS) and airborne-particle abrasion (APA) with 50-µm Al2O3, which were subdivided into 4 groups (n=6) according to the time of NTAP treatment: 0, 20, 60, and 120 seconds. The surface energy was evaluated with a goniometer. Forty Y-TZP blocks submitted to the same surface treatments (8 groups; n=5) were cemented to composite resin blocks, using a self-adhesive resin cement. After storage in distilled water at 37°C for 24 hours, the Y-TZP-composite resin blocks were cut into beams and submitted to a microtensile bond strength (µTBS) test. Data were analyzed using 2-way ANOVA and the Tukey honestly significant differences test (α=.05). RESULTS: Treatment with NTAP increased the surface energy for AS and APA groups (P<.05). For both groups, the µTBS was as follows: 0 seconds < 20 seconds < 60 seconds = 120 seconds (P<.05). Only after 120 seconds of NTAP treatment was the µTBS of APA higher than that of AS (P<.05). CONCLUSIONS: Treatment with NTAP improved the surface energy and increased the µTBS of self-adhesive resin cement to Y-TZP ceramic, with higher times of plasma treatment resulting in higher bond strength.


Subject(s)
Dental Bonding , Plasma Gases , Argon , Ceramics , Dental Cements , Dental Stress Analysis , Materials Testing , Resin Cements , Shear Strength , Surface Properties , Yttrium , Zirconium
8.
J Ethnopharmacol ; 220: 159-168, 2018 Jun 28.
Article in English | MEDLINE | ID: mdl-29079220

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: In Brazil, latex of Himatanthus drasticus is used to treat inflammation, wound healing and cancer. The present study evaluated the antitumoral potential of H. drasticus latex (HdCL) in Sarcoma 180-bearing mice (S180). MATERIALS AND METHODS: HdCL was obtained in Crato-CE, Brazil. Qualitative phytochemicals assays, nuclear magnetic resonance (NMR) and microbiological analyzes were performed. Swiss mice were divided into six groups, according to tumor forms: 1) ascitic model, GI (Control; 0.9% saline), GII (S180asc) and GIII (S180asc/HdCL/14 days); 2) solid model, GIV (Control; 0.9% saline), GV (S180sol) and GVI (S180sol/HdCL/10 days). HdCL and 0.9% saline were administered at 0.2 mL, SID, by gavage, for 10 or 14 days. For ascitic model, 0.5 mL of S180 suspension (4×106 cells/mL) was inoculated intraperitoneally and for solid model, cells were inoculated subcutaneously (25 µL) on the right hind paw of mice. Blood samples were collected for hematological and oxidative stress evaluation. Thickness, volume and weight of paws were measured in solid model. After euthanasia, spleen, liver and kidney were collected in order to assess the relative organ weight. Tissue fragments of paws and popliteal lymph nodes (PLN) were analyzed by H&E and CD4+, CD8+, HSP-60+ and Foxp3+ immunohistochemistry. RESULTS: HdCL presented milky aspect and pinkish supernatant. Phenols, flavonols, flavanones, free steroids and cinnamoyl derivatives of lupeol, α-amyrin and ß-amyrin were detected at the phytochemistry analysis. HdCL did not alter the relative weight of organs, hematological parameters and volume of ascitic fluid recovered. In solid model, HdCL reduced (P < 0.05) paw volume, but did not altered thickness, paw weight and histological parameters. S180sol induced necrosis, metastasis and destruction of bone, cartilage and muscles. Bleeding, vessel congestion and oncocytes were observed in PLN. In paw, HdCL did not alter FoxP3+ and HSP-60+ expressions but reduced the CD4+ and CD8+ expressions, while at PLN, HdCL reduced the expressions of all markers. HdCL decreased (P < 0.05) serum levels of malondialdehyde in ascitic model. CONCLUSIONS: Treatment with HdCL reduced oxidative damage and modulated the expressions of CD4+, CD8+, FoxP3+and HSP-60+ in S180 solid tumor model, which can be associated to the presence of triterpenes, such as α-amyrin, ß-amyrin and lupeol cinnamate. Present data emphasizes the importance of immune system in cancer and highlights the evaluation of the pharmacological properties of plants used by population as phytoterapics.


Subject(s)
Apocynaceae/chemistry , Oxidative Stress/drug effects , Plant Extracts/pharmacology , Sarcoma 180/drug therapy , Animals , Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Brazil , CD4 Antigens/genetics , CD8 Antigens/genetics , Chaperonin 60/genetics , Female , Forkhead Transcription Factors/genetics , Malondialdehyde/blood , Mice , Mitochondrial Proteins/genetics , Sarcoma 180/immunology , Sarcoma 180/pathology
9.
Biomed Res Int ; 2017: 5940479, 2017.
Article in English | MEDLINE | ID: mdl-29270433

ABSTRACT

The aim of this study was to evaluate the degree of conversion (DC%), water sorption (WS), solubility (SO), and resin-dentin bonding stability of experimental adhesive systems containing ZnCl2. Different concentrations (wt.%) of ZnCl2 were added to a model etch-and-rinse adhesive system consisting of BISGMA, HEMA, UDMA, GDMA, water, and ethanol: Zn0 (0%-control group); Zn2 (2%); Zn3.5 (3.5%); and Zn5 (5%). Adper Single Bond 2 (SB) was used as commercial reference. The samples were light cured for 20s using a quartz-tungsten-halogen unit (650 mW/cm2). DC% (n = 5) was measured using FT-IR spectroscopy, and WS and SO (n = 5) were calculated based on ISO4049. Microtensile bond strength (µTBS) and nanoleakage (NL) were measured after 24 h and 12 months of water storage (n = 10). Data were analyzed using ANOVA and Tukey's HSD test (5%). Zn5 presented the lowest DC% and the highest WS and SO (p < 0.05). Zn0 and Zn2 presented statistically similar DC%, WS, SO, and immediate µTBS. All adhesives containing ZnCl2 maintained a µTBS stability after 12 months, but only Zn2 and Zn3.5 did not suffer an increase in NL. SB presented the highest immediate µTBS but the greatest reduction after 12 months (p < 0.05). The addition of 2 wt.% of ZnCl2 in adhesive formulations seems to be a promising way to improve the resin-dentin bonding stability. Higher concentrations than 2 wt.% could impair some physicochemical properties.


Subject(s)
Chlorides/chemistry , Dental Cements/chemistry , Resins, Synthetic/chemistry , Zinc Compounds/chemistry , Acid Etching, Dental/methods , Chlorides/therapeutic use , Dental Bonding/instrumentation , Dental Cements/therapeutic use , Dentin/chemistry , Humans , Materials Testing , Resin Cements/chemistry , Resin Cements/therapeutic use , Resins, Synthetic/therapeutic use , Tensile Strength , Zinc Compounds/therapeutic use
10.
J Adhes Dent ; 18(6): 513-520, 2016.
Article in English | MEDLINE | ID: mdl-27869252

ABSTRACT

PURPOSE: To investigate the influence of 4-META concentration and type of solvent on the degree of conversion (DC%) and resin-dentin bond stability of experimental etch-and-rinse adhesives. MATERIALS AND METHODS: Four different concentrations of 4-META (12 wt%, 20 wt%, 30 wt%, 40 wt%) were added to a model adhesive system consisting of TEG-DMA (25 wt%), UDMA (20 wt%), HEMA (30 wt%), water (4 wt%), camphorquinone (0.5 wt%), and tertiary amine (0.5 wt%) dissolved in 20% acetone (A12, A20, A30 and A40) or 20% ethanol (E12, E20, E30 and E40). DC% was evaluated by FT-IR spectroscopy. Human molars were wet ground until the occlusal dentin was exposed, the adhesive systems were applied after 37% phosphoric acid etching, and resin composite buildups were incrementally constructed. After storage in distilled water at 37°C for 24 h, the teeth were cut into resin-dentin beams (cross-sectional area 1 mm2). Microtensile bond strength (µTBS) was evaluated after 24 h, 6 months, and 1 year of water storage at 37°C. The failure mode was categorized as adhesive, mixed, or cohesive. Data were analyzed using ANOVA and Tukey's HSD test (α = 0.05). RESULTS: A12 presented the lowest DC% (p < 0.05). All the other adhesive systems showed statistically similar DC% (p > 0.05). All adhesive systems maintained resin-dentin bond stability after 6 months of water storage, while only A40 and E40 maintained it after 1 year. CONCLUSION: Irrespective of the type of organic solvent, the incorporation of high concentrations of 4-META (40 wt%) improved the resin-dentin bond stability of the experimental etch-and-rinse adhesive systems over a period of 1 year.


Subject(s)
Acetone/pharmacology , Acid Etching, Dental/methods , Dental Bonding , Dentin-Bonding Agents , Ethanol/pharmacology , Methacrylates , Resins, Synthetic , Solvents/pharmacology , Humans , Materials Testing
11.
J Adhes Dent ; 18(5): 425-434, 2016.
Article in English | MEDLINE | ID: mdl-27669634

ABSTRACT

PURPOSE: To evaluate the effect of dentin treatment using HEMA phosphate (HEMA-P) on the microtensile bond strength (µTBS) and nanoleakage of an etch-and-rinse adhesive system. MATERIALS AND METHODS: The occlusal surfaces of human molars were wet ground until superficial dentin was exposed. The specimens were then assigned to two groups according to dentin treatment: PA: 37% H3PO4 for 15 s; or HP: HEMA-P for 15 s. Adper Single Bond 2 was applied to the treated dentin surfaces and resin composite buildups were incrementally constructed over them. After 24-h storage in artificial saliva at 37°C, the bonded teeth were cut into resin-dentin sticks with a cross-sectional area of 1 mm², which were submitted to µTBS testing immediately or after 3 months of storage in artificial saliva at 37°C. Nanoleakage was assessed using SEM/EDS, and the interaction between dentin and H3PO4 or HEMA-P was evaluated by combining micro-Raman and FT-IR spectroscopy. The data were analyzed using two-way ANOVA and Tukey's HSD post-hoc test (α = 0.05). RESULTS: HP presented significantly higher µTBS than PA at both times (p < 0.05). Both treatments maintained µTBS stability after 3 months of artificial saliva storage (p > 0.005). At both times, PA presented higher nanoleakage than HP (p < 0.05). CONCLUSIONS: Both dentin treatments maintained µTBS stability after 3 months of artificial saliva storage. The use of HEMA-P was associated with less nanoleakage than was traditional phosphoric-acid etching.


Subject(s)
Dental Bonding , Dental Cements , Dental Etching , Dentin/drug effects , Methacrylates/pharmacology , Dental Leakage , Humans , In Vitro Techniques , Materials Testing , Microscopy, Electron, Scanning , Surface Properties
12.
Rev. bras. ciênc. vet ; 23(1-2): 48-54, jan./jun. 2016. il.
Article in Portuguese | LILACS | ID: biblio-995424

ABSTRACT

O presente estudo avaliou o estresse oxidativo e a adesão de leucócitos (AL) em cães naturalmente infectados por Leishmania infantum. Foram utilizados cães saudáveis (CN = 10) e cães acometidos por leishmaniose visceral na forma sintomática (CS = 10), submetidos previamente a exames de imunofluorescência indireta (IFI), ensaio imunoenzimático (ELISA) e pesquisa do parasito em aspirados de medula óssea. Soro foi utilizado para avaliação de malondialdeído (MDA) no ensaio para espécies reativas ao ácido tiobarbitúrico (TBARS) e AL foi determinada pelo método da coluna de náilon em sangue em EDTA, heparina e citrato. Os dados de AL foram expressos em porcentagem e MDA em média ± desvio padrão, submetidos ao teste T de student não pareado (p < 0,05). Amostras em heparina apresentaram níveis mais elevados de AL no grupo CS (55,62%, p < 0,05) quando comparadas com EDTA e citrato (10,46% e 5,28%). Citrato e EDTA inibiram AL em cães doentes e saudáveis, enquanto a heparina preservou a AL. A proporção neutrofílica se apresentou reduzida nas amostras em heparina (85% para 67%, p <0,05) quando comparadas com citrato e EDTA, que por sua vez mantiveram-se estáveis (83% para 80%). Os níveis de MDA apresentaram-se mais elevados em CS (0,0117µM ± 0,002) quando comparado com CN (0,0057µM ± 0,001) (p <0,05). Estes dados dão suporte à conclusão de que na LVC ocorre elevação do estresse oxidativo e aumento da expressão das moléculas de adesão nos leucócitos, evidenciando resposta inflamatória sistêmica. A escolha do anticoagulante é importante para a implementação do ensaio de AL.


The present study evaluated the oxidative stress and leukocyte adhesion (LA) in dogs naturally infected by Leishmania infantum. Healthy dogs (HD = 10) and dogs affected by canine visceral leishmaniasis (CVL) in symptomatic form (SD= 10) were previously submitted to indirect immunofluorescence reaction (IIF), enzyme-linked immunosorbent assay (ELISA) and detection of parasites in bone marrow aspirates. Serum was used to assess malondialdeid (MDA) by thiobarbituric acid reactive species (TBARS) assay and AL was determined by nylon column method using whole blood stored in EDTA, citrate and heparin. AL data was expressed as percentage and MDA data as mean ± standard deviation, both submitted to the unpaired student's T test (p < 0.05). Heparin samples showed higher levels of AL in CS group (55.62 %, p < 0.05) when compared with EDTA and citrate (10.46% and 5.28%). Citrate and EDTA inhibit AL in healthy and sick dogs, while heparin preserved AL in both groups. Neutrophil proportion in heparin samples were lower (85% to 67%, p <0.05) compared with citrate and EDTA, which in turn remained practically unchanged (83% to 80%). MDA levels were higher in SD (0.0117µM ± 0.002) when compared to HD (0.0057µM ± 0.001) (p <0.05). These data support the conclusion that CVL induces oxidative stress enhance and leukocyte adhesion increase, indicating systemic inflammatory response. The choice of anticoagulant is an important decision for implementing LA assays.


Subject(s)
Male , Psittaciformes , Heparin , Polymerase Chain Reaction , Dog Diseases , Animals, Wild
13.
Biosens Bioelectron ; 77: 746-51, 2016 Mar 15.
Article in English | MEDLINE | ID: mdl-26499871

ABSTRACT

A hybrid platform based on ionic liquid-based alkoxysilane functionalized mesoporous silica was applied for the synthesis of supported Pt nanoparticles with peroxidase-like catalytic activity. The positively charged groups (imidazolium) chemically bonded to the surface provide dual-functionality as ion-exchangers to the hybrid material, firstly used for the in situ synthesis of the highly dispersed Pt nanostructures and, secondly, for the immobilization of biological species aiming biosensing purposes. The peroxidase-like catalytic activity of the SiO2/Imi/Pt material was evaluated towards the H2O2-mediated oxidation of a chromogenic peroxidase substrate (TMB), allowing the colorimetric detection of H2O2. Finally, to further explore the practical application of this nanomaterial-based artificial system, glucose oxidase (GOx) was immobilized on the catalytic porous platform and a bioassay for the colorimetric determination of glucose was successfully conducted as a model system. The enzyme-like catalytic properties of the SiO2/Imi/Pt as well as its ability to immobilize and keep active biological entities on the porous structure indicate that this hybrid porous platform is potentially useful for the development of biosensing devices.


Subject(s)
Colorimetry/instrumentation , Glucose Oxidase/chemistry , Glucose/analysis , Hydrogen Peroxide/analysis , Metal Nanoparticles/chemistry , Platinum/chemistry , Biomimetic Materials/chemistry , Catalysis , Complex Mixtures/analysis , Complex Mixtures/chemistry , Enzymes, Immobilized/chemistry , Horseradish Peroxidase/chemistry , Imidazoles/chemistry , Ionic Liquids/chemistry
14.
Article in Portuguese | LILACS, MOSAICO - Integrative health | ID: biblio-948010

ABSTRACT

O estudo etnofarmacológico contribui para a descoberta de novos fármacos e de forma especial, aqueles voltados para a terapia anticancer. Os tumores acometem diversos tecidos de forma benigna ou maligna. Nesta última situação inclui-se além do crescimento anormal das células, a invasão de novos tecidos em virtude da dispersão das células tumorais, conduzindo o indivíduo à morte em muitos casos. Uma vez que os medicamentos anticancerígenos afetam gravemente as células normais, ressalta-se que o uso de extratos de plantas e produtos derivados no tratamento do câncer é de fundamental valor no controle de doenças crônicas. A utilização de plantas medicinais estende-se por todos os continentes, variando na disponibilidade vegetal específica/nativa e nos valores culturais e históricos dos povos. A validação científica de preparações medicinais utilizadas popularmente acaba levando não só a confirmação de novas formas de se tratar o câncer, mas de forma paralela nos leva a compreender, por meio dos ensaios pré-clínicos, o mecanismo de ação de compostos bioativos sobre as células tumorais.


Subject(s)
Humans , Plants, Medicinal , Ethnobotany , Antineoplastic Agents , Brazil , Plant Extracts , Phytotherapy
15.
J Dent ; 43(12): 1491-7, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26456899

ABSTRACT

OBJECTIVES: To evaluate the degree of conversion (DC%), water sorption (WS), solubility (SO) and the resin-dentin bonding stability (µTBS) of experimental (EXP) etch-and-rinse adhesive systems containing MMP-inhibitors: Galardin-GAL, Batimastat-BAT, GM1489-GM1 and chlorhexidine diacetate-CHX. METHODS: DC% was measured using FT-IR spectroscopy, while WS and SO were calculated based on ISO4049. Thirty-six human molars were wet ground until the occlusal dentin was exposed. The adhesive systems were applied and resin composite buildups were incrementally constructed. After 24 h immersion in distilled water at 37 °C, the specimens were cut into resin-dentin beams with a cross-sectional area of 1 mm(2). The µTBS was evaluated after 24 h, 6 months and 12 months of water storage at 37 °C. Adper Single Bond 2 (SB2) was used as a commercial control. The data were analyzed using ANOVA and Tukey's HSD test. RESULTS: SB2 presented the highest DC% (p<0.05). CHX presented the lowest WS (p<0.05). GM1, GAL and BAT presented similar WS when compared with SB2 (p>0.05). SO was found to be not significant (p>0.05). All adhesive systems maintained µTBS stability after 6 months of water storage. Only BAT, GM1 and CHX maintained µTBs stability after 12 months of water storage. CONCLUSIONS: The experimental adhesive systems with GM1489 and chlorhexidine diacetate presented the best physicochemical properties and preserved resin-dentin bonding stability after 12 months of water storage. CLINICAL SIGNIFICANCE: GM1489 could be suitable for inclusion as an MMP-inhibitor in etch-and-rinse adhesive systems to maintain resin-dentin bonding stability over time.


Subject(s)
Acid Etching, Dental/methods , Dental Bonding/methods , Dentin-Bonding Agents/chemistry , Matrix Metalloproteinase Inhibitors/chemistry , Resins, Synthetic/chemistry , Chlorhexidine/chemistry , Chlorhexidine/pharmacology , Composite Resins/chemistry , Dentin/drug effects , Humans , Materials Testing , Matrix Metalloproteinase Inhibitors/pharmacology , Methacrylates/chemistry , Molar , Resin Cements/chemistry , Water/chemistry
16.
Mem Inst Oswaldo Cruz ; 110(4): 569-72, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26061233

ABSTRACT

In the early 2015, several cases of patients presenting symptoms of mild fever, rash, conjunctivitis and arthralgia were reported in the northeastern Brazil. Although all patients lived in a dengue endemic area, molecular and serological diagnosis for dengue resulted negative. Chikungunya virus infection was also discarded. Subsequently, Zika virus (ZIKV) was detected by reverse transcription-polymerase chain reaction from the sera of eight patients and the result was confirmed by DNA sequencing. Phylogenetic analysis suggests that the ZIKV identified belongs to the Asian clade. This is the first report of ZIKV infection in Brazil.


Subject(s)
Aedes/virology , Insect Vectors/virology , Zika Virus Infection/transmission , Zika Virus Infection/virology , Zika Virus/genetics , Adolescent , Adult , Aged , Animals , Brazil/epidemiology , Female , Humans , Male , Middle Aged , Phylogeny , Polymerase Chain Reaction , RNA, Viral/genetics , Sequence Analysis, DNA , Young Adult , Zika Virus/isolation & purification , Zika Virus Infection/epidemiology , Zika Virus Infection/pathology
17.
Mem. Inst. Oswaldo Cruz ; 110(4): 569-572, 09/06/2015. graf
Article in English | LILACS | ID: lil-748856

ABSTRACT

In the early 2015, several cases of patients presenting symptoms of mild fever, rash, conjunctivitis and arthralgia were reported in the northeastern Brazil. Although all patients lived in a dengue endemic area, molecular and serological diagnosis for dengue resulted negative. Chikungunya virus infection was also discarded. Subsequently, Zika virus (ZIKV) was detected by reverse transcription-polymerase chain reaction from the sera of eight patients and the result was confirmed by DNA sequencing. Phylogenetic analysis suggests that the ZIKV identified belongs to the Asian clade. This is the first report of ZIKV infection in Brazil.


Subject(s)
Adolescent , Adult , Aged , Animals , Female , Humans , Male , Middle Aged , Young Adult , Aedes/virology , Insect Vectors/virology , Zika Virus Infection/transmission , Zika Virus/genetics , Base Sequence , Brazil/epidemiology , Phylogeny , Polymerase Chain Reaction , RNA, Viral , Sequence Analysis, DNA , Zika Virus Infection/epidemiology , Zika Virus Infection/virology , Zika Virus/isolation & purification
18.
J Chromatogr Sci ; 53(8): 1257-64, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25637135

ABSTRACT

We have optimized an SPE-LC-ESI-MS/MS method and used it to monitor disperse azo dyes in environmental aquatic samples. Calibration curves constructed for nine disperse dyes-Red 1, Violet 93, Blue 373, Orange 1, Orange 3, Orange 25, Yellow 3, Yellow 7 and Red 13-in aqueous solution presented good linearity between 2.0 and 100.0 ng mL(-1). The method provided limits of detection and quantification around 2.0 and 8.0 ng L(-1), respectively. For dyes at concentrations of 25.0 ng mL(-1), the intra- and interday analyses afforded relative standard deviation lower than 6 and 13%, respectively. The recovery values obtained for each target analyte in Milli-Q water, receiving waters and treated water samples spiked with the nine studied dyes at concentrations of 8.0, 25.0 and 50.0 ng L(-1) (n = 3) gave average recoveries greater than 70%, with RSD <20%. Statistical evaluation aided method validation. The validated method proved to be useful for analysis of organic extracts from effluents and receiving water samples after an SPE extraction step. More specifically, the method enabled detection of the dyes Disperse Red 1, Disperse Blue 373 and Disperse Violet 93 at concentrations ranging from 84 to 3452 ng L(-1) in the treated effluent (TE), affluent and points collected upstream and downstream of the drinking water treatment plant of a textile dye industry in Brazil.


Subject(s)
Chromatography, Liquid/methods , Coloring Agents/analysis , Solid Phase Extraction/methods , Tandem Mass Spectrometry/methods , Water Pollutants, Chemical/analysis , Coloring Agents/chemistry , Coloring Agents/isolation & purification , Linear Models , Reproducibility of Results , Sensitivity and Specificity , Spectrometry, Mass, Electrospray Ionization , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/isolation & purification
19.
Bioanalysis ; 6(1): 89-106, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24341497

ABSTRACT

Paper has become increasingly recognized as a very interesting substrate for the construction of microfluidic devices, with potential application in a variety of areas, including health diagnosis, environmental monitoring, immunoassays and food safety. The aim of this review is to present a short history of analytical systems constructed from paper, summarize the main advantages and disadvantages of fabrication techniques, exploit alternative methods of detection such as colorimetric, electrochemical, photoelectrochemical, chemiluminescence and electrochemiluminescence, as well as to take a closer look at the novel achievements in the field of bioanalysis published during the last 2 years. Finally, the future trends for production of such devices are discussed.


Subject(s)
Environmental Monitoring/instrumentation , Microfluidic Analytical Techniques/instrumentation , Microfluidics/instrumentation , Paper , Bacteria/isolation & purification , Biological Products/analysis , Biomarkers/analysis , Colorimetry/methods , Electrochemical Techniques , Food Safety/methods , Humans , Luminescent Measurements , Microfluidic Analytical Techniques/trends , Microfluidics/methods , Microfluidics/trends , Pesticides/analysis , Photochemical Processes
20.
Analyst ; 139(1): 273-9, 2014 Jan 07.
Article in English | MEDLINE | ID: mdl-24223422

ABSTRACT

This paper describes the molecular modeling design, synthesis and characterization of a new bio-inspired hexapeptide of acetylcholinesterase enzyme and its interaction with the organophosphate pesticide dichlorvos monitored by UV-Vis spectroscopy and mass spectrometry. This strategy can contribute to the development of synthetic receptors to be coupled to biosensor transducers, avoiding the issues associated with proteins such as low stability under different pH and temperature conditions and high production cost. The resulting data of this work indicate a strong interaction between the pesticide dichlorvos and the hexapeptide (NH3(+)-Glu-His-Gly-Gly-Pro-Ser-COO(-)) with a binding constant of 4.10 × 10(5) M(-1) and the formation of an adduct by covalent binding on the serine residue from the hexapeptide.


Subject(s)
Acetylcholinesterase/chemistry , Dichlorvos/analysis , Drug Design , Mass Spectrometry/methods , Oligopeptides/chemical synthesis , Pesticides/analysis , Acetylcholinesterase/metabolism , Dichlorvos/metabolism , Oligopeptides/metabolism , Pesticides/metabolism , Protein Binding/physiology , Protein Structure, Secondary , Protein Structure, Tertiary , Solid-Phase Synthesis Techniques/methods
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