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1.
J Appl Microbiol ; 130(3): 745-754, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32750211

RESUMO

AIMS: To evaluate the anti-staphylococcal effects of lectins isolated from bark (MuBL), heartwood (MuHL) and leaves (MuLL) of Myracrodruon urundeuva. METHODS AND RESULTS: The lectins were evaluated for: effects on growth, aggregation, haemolytic activity and biofilm-forming ability of Staphylococcus aureus clinical isolates nonresistant (8325-4) and multidrug resistant (LAC USA300); interference with the expression of virulence genes (hla, rnaIII and spa) of the Agr system of S. aureus; and synergistic effect with the antibiotics cefoxitin and cefotaxime. MuBL, MuHL and MuLL reduced growth (minimal inhibitory concentration (MIC): 12·5-50 µg ml-1 ) and viability (minimal bactericidal concentration (MBC): 100 µg ml-1 ) of 8325-4 and LAC USA300 cells. MuLL (at ½MIC and MIC) reduced LAC USA300 agglutination. The lectins did not interfere with haemolytic activity and expression of hla, rnaIII and spa genes. Only MuHL was able to reduce the biofilm production by 8325-4 (50-400 µg ml-1 ) and LAC USA300 (400 µg ml-1 ). CONCLUSION: The M. urundeuva lectins showed antibacterial activity against nonresistant and resistant clinical isolates of S. aureus and synergistic effects with antibiotics in reducing growth and biofilm formation. SIGNIFICANCE AND IMPACT OF THE STUDY: This work reports bioactive molecules capable of acting as anti-staphylococcal agents, since there are increasing reports of multiresistant isolates of this bacterium.


Assuntos
Anacardiaceae/química , Antibacterianos/farmacologia , Lectinas de Plantas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Testes de Aglutinação , Antibacterianos/isolamento & purificação , Biofilmes/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Hemólise/efeitos dos fármacos , Humanos , Lectinas de Plantas/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/patogenicidade , Virulência/efeitos dos fármacos
2.
Microb Pathog ; 147: 104273, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32473391

RESUMO

The present study was developed to characterize, at the species level, 34 strains of Aeromonas spp., previously isolated from stressed tambaqui fish (Colossoma macropomum), to elucidate virulence factors, as well as their antibiotic resistance profile. Amplification of the gyrB gene identified the strains as A. hydrophila, A. dhakensis, A. caviae, A. veronii and A. jandaei. Bacterial virulence was evaluated by enzymatic assays for phenotypical production of hemolysins, proteases and lipases followed by the search for genes codifying the enzymes ß-hemolysin, serine protease and lipase. Phenotypical production of virulence factors was diversified and proteolytic activity demonstrated to be a common expression among the strains. On the other hand, the lip gene encoding extracellular lipase was the most expressed. Furthermore, A. hydrophila was the most prevalent species isolated from tambaqui in our work.


Assuntos
Aeromonas , Caraciformes , Infecções por Bactérias Gram-Negativas , Aeromonas/genética , Animais , Antibacterianos , Infecções por Bactérias Gram-Negativas/veterinária , Virulência
3.
Sensors (Basel) ; 19(7)2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30925686

RESUMO

We present a portable and low-cost system for interrogation of long-period fiber gratings (LPFGs) costing around a 30th of the price of a typical setup using an optical spectrum analyzer and a broadband light source. The unit is capable of performing real-time monitoring or as a stand-alone data-logger. The proposed technique uses three thermally modulated fiber-coupled laser diodes, sweeping a few nanometers around their central wavelength. The light signal is then modulated by the LPFG and its intensity is acquired by a single photo-detector. Through curve-fitting algorithms the sensor transmission spectrum is reconstructed. Testing and validation were accomplished by inducing variations in the spectral features of an LPFG through changes either in external air temperature from 22 to 425 °C or in refractive index (RI) of the surrounding medium from 1.3000 to 1.4240. A dynamic resolution between 3.5 and 1.9 °C was achieved, in temperatures from 125 to 325 °C. In RI measurements, maximum wavelength and optical power deviations of 2.75 nm and 2.86 dB, respectively, were obtained in the range from 1530 to 1570 nm. The worse RI resolution obtained was 3.47 × 10 - 3 . The interrogation platform was then applied in the detection of iron corrosion, expressing wavelength peak values within 1.12 nm from the real value in the region between 1530 and 1570 nm.

4.
Sensors (Basel) ; 19(24)2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31847169

RESUMO

A sensing configuration for the real-time monitoring, detection, and quantification of dissolved carbon dioxide (dCO2) was developed for aquaculture and other applications in freshwater and saline water. A chemical sensing membrane, based on a colorimetric indicator, is combined with multimode optical fiber and a dual wavelength light-emitting diode (LED) to measure the dCO2-induced absorbance changes in a self-referenced ratiometric scheme. The detection and processing were achieved with an embeded solution having a mini spectrometer and microcontroller. For optrode calibration, chemical standard solutions using sodium carbonate in acid media were used. Preliminary results in a laboratory environment showed sensitivity for small added amounts of CO2 (0.25 mg·L-1). Accuracy and response time were not affected by the type of solution, while precision was affected by salinity. Calibration in freshwater showed a limit of detection (LOD) and a limit of quantification (LOQ) of 1.23 and 1.87 mg·L-1, respectively. Results in saline water (2.5%) showed a LOD and LOQ of 1.05 and 1.16 mg·L-1, respectively. Generally, performance was improved when moving from fresh to saline water. Studies on the dynamics of dissolved CO2 in a recirculating shallow raceway system (SRS+RAS) prototype showed higher precision than the tested commercial sensor. The new sensor is a compact and robust device, and unlike other sensors used in aquaculture, stirring is not required for correct and fast detection. Tests performed showed that this new sensor has a fast accurate detection as well as a strong potential for assessing dCO2 dynamics in aquaculture applications.


Assuntos
Aquicultura/métodos , Dióxido de Carbono/análise , Águas Salinas/análise , Colorimetria , Monitoramento Ambiental/métodos , Fibras Ópticas
5.
Int Ophthalmol ; 39(2): 341-345, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29340891

RESUMO

PURPOSE: To compare MMC 0.002% efficacy in preventing haze after PRK in relation to MMC 0.02%. PATIENTS AND METHODS: We conducted a prospective study with patients with myopia or myopic astigmatism undergoing PRK in the same conditions. After PRK, MMC was applied for 30 s in a concentration of 0.02% on the right eye (group 1) and 0.002% on the left eye (group 2). Age, gender, spherical equivalent and haze intensity (1, 3, 6 and 12 months postoperatively) were assessed. Haze was quantified at biomicroscopy (0-4 +). P < 0.05 was considered statistical significant. RESULTS: We evaluated 130 patients, 77 women and 53 men, with a mean age of 30.2 ± 9 years. The spherical equivalent was - 3.66 D in the group 1 and - 3.77 D in the group 2. In the 1st month after PRK, incidence of haze was 13.9% eyes in group 1 and 14.6% in group 2. In the 3rd month, incidence of haze was 50.0% eyes in group 1 and 48.5% in group 2 which presented with 3 +/4 + traces of haze. In the 12th month, incidence of haze was 7.7% eyes in group 1 and 5.4% in group 2. There was no correlation between haze and age (p = 0.279/0.333), gender (p = 0.345/0.367) or spherical equivalent (p = 0.100/0.054) in groups 1 and 2, respectively. There was no difference in haze between groups 1 and 2 (p = 0.56). CONCLUSION: MMC 0.002% was effective in preventing haze after PRK. As MMC long-term safety has not been proved, we suggest its use in a lower concentration, in order to prevent potential complications.


Assuntos
Mitomicina/administração & dosagem , Miopia/cirurgia , Ceratectomia Fotorrefrativa/efeitos adversos , Complicações Pós-Operatórias/prevenção & controle , Refração Ocular/fisiologia , Acuidade Visual , Adolescente , Adulto , Idoso , Antibióticos Antineoplásicos/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Lasers de Excimer/uso terapêutico , Masculino , Microscopia Acústica , Pessoa de Meia-Idade , Miopia/fisiopatologia , Soluções Oftálmicas , Complicações Pós-Operatórias/diagnóstico , Estudos Prospectivos , Fatores de Tempo , Adulto Jovem
6.
J Appl Microbiol ; 125(5): 1238-1252, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30053345

RESUMO

The resistance of micro-organisms to antimicrobial agents has been a challenge to treat animal and human infections, and for environmental control. Lectins are natural proteins and some are potent antimicrobials through binding to carbohydrates on microbial surfaces. Oligomerization state of lectins can influence their biological activity and maximum binding capacity; the association among lectin polypeptide chains can alter the carbohydrate-lectin binding dissociation rate constants. Antimicrobial mechanisms of lectins include the pore formation ability, followed by changes in the cell permeability and latter, indicates interactions with the bacterial cell wall components. In addition, the antifungal activity of lectins is associated with the chitin-binding property, resulting in the disintegration of the cell wall or the arrest of de novo synthesis from the cell wall during fungal development or division. Quorum sensing is a cell-to-cell communication process that allows interspecies and interkingdom signalling which coordinate virulence genes; antiquorum-sensing therapies are described for animal and plant lectins. This review article, among other approaches, evaluates lectins as antimicrobials.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Resistência Microbiana a Medicamentos , Fungos/efeitos dos fármacos , Lectinas/farmacologia , Animais , Infecções Bacterianas/microbiologia , Humanos , Micoses/microbiologia , Percepção de Quorum/efeitos dos fármacos
7.
Med Oral Patol Oral Cir Bucal ; 23(1): e44-e48, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29274157

RESUMO

BACKGROUND: To determine the frequency of nonsyndromic cleft lip and/or palate (NSCL/P) in first-degree relatives and to analyze the prevalence of tooth agenesis in patients with gastric cancer. MATERIAL AND METHODS: This cross-sectional, observational, case-control study included 798 patients attended at hospital Santa Casa in Montes Claros, Minas Gerais and Alfa Institute of Gastroenterology of the Federal University of the Minas Gerais. Information on basic demographic data and tooth agenesis of both groups and their family history of NSCL/P in first-degree relatives were evaluated. The collected information was stored in a database and analyzed using statistical program SPSS version 21.0 and the values with p<0.05 were considered statistically significant. RESULTS: Of the 798 patients, 113 (14.16%) consisted of the case group and 685 of the control group (85.84%). Non-Caucasian males were the most affected, although no differences among the groups were detected. Of all participants (n=798), 66 (8.27%) presented tooth agenesis and 25 (3.13%) presented oral cleft in first degree relative. CONCLUSIONS: Our results no found increase in the frequency of tooth agenesis in patients with gastric cancer and in the frequency of NSCL/P in the first-degree relatives of patients with gastric cancer.


Assuntos
Anodontia/complicações , Encéfalo/anormalidades , Fenda Labial/complicações , Fissura Palatina/complicações , Neoplasias Gástricas/complicações , Anodontia/epidemiologia , Estudos de Casos e Controles , Fenda Labial/epidemiologia , Fissura Palatina/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência
8.
J Appl Microbiol ; 123(4): 861-874, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28792661

RESUMO

AIMS: To evaluate the antibiofilm potential of water-soluble Moringa oleifera seed lectin (WSMoL) on Serratia marcescens and Bacillus sp. METHODS AND RESULTS: WSMoL inhibited biofilm formation by S. marcescens at concentrations lower than 2·6 µg ml-1 and impaired bacterial growth at higher concentrations, avoiding biofilm formation. For Bacillus sp., the lectin inhibited bacterial growth at all concentrations. The antibiofilm action of WSMoL is associated with damage to bacterial cells. WSMoL did not disrupt preformed S. marcescens biofilms but was able to damage cells inside them. On the other hand, the lectin reduced the number of cells in Bacillus sp. biofilm treated with it. WSMoL was able to control biofilm formation when immobilized on glass surface (116 µg cm-2 ), damaging S. marcescens cells and avoiding adherence of Bacillus sp. cells on glass. The Bacillus sp. isolate is member of Bacillus subtilis species complex and closely related to species of the conspecific 'amyloliquefaciens' group. CONCLUSION: WSMoL prevented biofilm development by S. marcescens and Bacillus sp. and the antibiofilm effect is also observed when the lectin is immobilized on glass. SIGNIFICANCE AND IMPACT OF THE STUDY: Taking together, our results provide support to the potential use of WSMoL for controlling biofilm formation by bacteria.


Assuntos
Antibacterianos/farmacologia , Bacillus/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Lectinas/farmacologia , Moringa oleifera/química , Extratos Vegetais/farmacologia , Serratia marcescens/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Bacillus/fisiologia , Lectinas/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Sementes/química , Serratia marcescens/fisiologia
9.
Eur J Clin Microbiol Infect Dis ; 34(3): 497-509, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25311987

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) isolates genetically related to the CA-MRSA clone MW2/USA400 (ST1-SCCmecIV lineage) from the United States have emerged in hospitals in Rio de Janeiro and are associated with nosocomial bloodstream infections. To understand the virulence mechanisms involved in the adaptability of ST1 isolates as a hospital pathogen in Rio de Janeiro, we compared the virulence traits and fitness properties of the Brazilian isolates with those displayed by the CA-MRSA isolates from the United States. Similar to the USA400 from the United States, all the Brazilian isolates tested carried the genes encoding SEH and LukDE. In contrast, none of the Brazilian isolates carried the lukSF PVL, sea, sec, and sek genes. Competition experiments in mice demonstrated a significant increase in the fitness for the CA-MRSA isolates MW2 and USA400-0051 from the United States compared to other isolates. In the foreign body animal model, 83 % more North-American bacterial cells were recovered compared to the Brazilian ST1 isolates. Differences in gene expression of important virulence factors were detected. Transcription of rnaIII and psmα3 was increased about two-fold in the isolates from the United States, and sasG about two-fold in the Brazilian isolates. Thus, it is possible that the virulence attenuation observed among the Brazilian hospital isolates, associated with the acquisition of multiple resistant determinants, are consequences of microevolutionary events that contributed to the necessary fitness adjustment of this lineage, allowing a typically community-acquired MRSA (MW2/USA400) to emerge as a successful hospital pathogen (Brazilian ST1-SCCmecIV).


Assuntos
Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/microbiologia , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/fisiologia , Infecções Estafilocócicas/microbiologia , Fatores de Virulência/genética , Animais , Evolução Biológica , Brasil , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Genes Bacterianos , Genótipo , Humanos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Camundongos , Estados Unidos , Virulência
10.
J Pineal Res ; 58(4): 490-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25807895

RESUMO

This study investigated the maturational stage (immature and mature ovaries) differences of mRNA expression of melatonin-forming enzymes (Aanat and Asmt), melatonin membrane receptors (Mt1 and Mt2) and putative nuclear (Rorα) receptors, and clock genes (Clock, Bmal1, Per1, Per2, Cry1, Cry2) in cumulus-oocyte complexes (COC) from weaning Wistar rats. We also examined the effects of pinealectomy and of melatonin pharmacological replacement on the daily expression of these genes in COC. qRT-PCR analysis revealed that in oocytes, the mRNA expression of Asmt, Mt2, Clock, Bmal1, Per2, and Cry1 were higher (P < 0.05) in immature ovaries than in the mature ones. In cumulus cells, the same pattern of mRNA expression for Asmt, Aanat, Rorα, Clock, Per1, Cry1, and Cry2 genes was observed. In oocytes, pinealectomy altered the daily mRNA expression profiles of Asmt, Mt1, Mt2, Clock, Per1, Cry1, and Cry2 genes. In cumulus cells, removal of the pineal altered the mRNA expression profiles of Mt1, Mt2, Rorα, Aanat, Asmt, Clock, Bmal1, Per2, Cry1, and Cry2 genes. Melatonin treatment partially or completely re-established the daily mRNA expression profiles of most genes studied. The mRNA expression of melatonin-related genes and clock genes in rat COC varies with the maturational stage of the meiotic cellular cycle in addition to the hour of the day. This suggests that melatonin might act differentially in accordance with the maturational stage of cumulus/oocyte complex. In addition, it seems that circulating pineal melatonin is very important in the design of the daily profile of mRNA expression of COC clock genes and genes related to melatonin synthesis and action.


Assuntos
Células do Cúmulo/metabolismo , Melatonina/metabolismo , Oócitos/metabolismo , Glândula Pineal/cirurgia , Animais , Arilalquilamina N-Acetiltransferase/metabolismo , Ritmo Circadiano/fisiologia , Feminino , Proteínas Circadianas Period/metabolismo , Ratos , Ratos Wistar , Receptores de Melatonina/metabolismo
11.
J Appl Microbiol ; 119(3): 666-76, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26109449

RESUMO

AIMS: This work evaluated the antibacterial activity of a water-soluble Moringa oleifera seed lectin (WSMoL) by evaluating its effect on growth, survival and cell permeability of Bacillus sp., Bacillus cereus, Bacillus pumillus, Bacillus megaterium, Micrococcus sp., Pseudomonas sp., Pseudomonas fluorescens, Pseudomonas stutzeri and Serratia marcescens. In addition, the effect of lectin on membrane integrity of most sensitive species was also evaluated. All the tested bacteria are able to cause biocorrosion and some are also responsible for human infections. METHODS AND RESULTS: WSMoL inhibited the bacterial growth, induced agglutination and promoted the leakage of proteins from cells of all strains. Bactericidal effect was detected against Bacillus sp., B. pumillus, B. megaterium, Ps. fluorescens and Ser. marcescens. The bacteriostatic effect of lectin was evident with only 6 h of incubation. Fluorescence microscopy of Ser. marcescens showed that WSMoL caused loss of cell integrity and indicated an anti-biofilm activity of the lectin. CONCLUSIONS: WSMoL was active against the bacteria by inhibiting growth and affecting cell permeability. The lectin also interfered with membrane integrity of Ser. marcescens, the most sensitive species. SIGNIFICANCE AND IMPACT OF THE STUDY: The study indicates that WSMoL was active against bacteria that cause serious problems in both industrial and health sectors. Also, the study contributes for the 'state-of-art' on antibacterial mechanisms of lectins.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Lectinas/farmacologia , Moringa oleifera/química , Extratos Vegetais/farmacologia , Antibacterianos/química , Bactérias/crescimento & desenvolvimento , Lectinas/química , Viabilidade Microbiana/efeitos dos fármacos , Permeabilidade/efeitos dos fármacos , Extratos Vegetais/química , Sementes/química
12.
Appl Opt ; 54(35): 10342-8, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26836856

RESUMO

A study of a sensor for hydrogen (H2) detection based on fiber Bragg gratings coated with palladium (Pd) with self-temperature compensation is presented. The cladding around the gratings was reduced down to 50 µm diameter by a chemical etching process. One of the gratings was left uncoated, and the other was coated with 150 nm of Pd. It was observed that palladium hydride has unstable behavior in environments with high humidity level. A simple solution to overcome this problem based on a Teflon tape is presented. The sensing device studied was able to respond to H2 concentrations in the range 0%-1% v/v at room temperature and atmospheric pressure, achieving sensitivities larger than 20 pm/% v/v. Considering H2 concentrations in nitrogen up to 1%, the performance of the sensing head was characterized for different thicknesses of Pd coating ranging from 50 to 200 nm.

13.
Scand J Med Sci Sports ; 25(5): e524-30, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25556301

RESUMO

To evaluate the effects of a single session of partial-body cryotherapy (PBC) on muscle recovery, 26 young men performed a muscle-damaging protocol that consisted of five sets of 20 drop jumps with 2-min rest intervals between sets. After the exercise, the PBC group (n = 13) was exposed to 3 min of PBC at -110 °C, and the control group (n = 13) was exposed to 3 min at 21 °C. Anterior thigh muscle thickness, isometric peak torque, and muscle soreness of knee extensors were measured pre, post, 24, 48, 72, and 96 h following exercise. Peak torque did not return to baseline in control group (P < 0.05), whereas the PBC group recovered peak torques 96 h post exercise (P > 0.05). Peak torque was also higher after PBC at 72 and 96 h compared with control group (P < 0.05). Muscle thickness increased after 24 h in the control group (P < 0.05) and was significantly higher compared with the PBC group at 24 and 96 h (P < 0.05). Muscle soreness returned to baseline for the PBC group at 72 h compared with 96 h for controls. These results indicate that PBC after strenuous exercise may enhance recovery from muscle damage.


Assuntos
Crioterapia/métodos , Músculo Quadríceps/fisiopatologia , Recuperação de Função Fisiológica , Adolescente , Exercício Físico/fisiologia , Humanos , Contração Isométrica , Masculino , Mialgia/terapia , Músculo Quadríceps/diagnóstico por imagem , Músculo Quadríceps/patologia , Fatores de Tempo , Torque , Ultrassonografia , Adulto Jovem
14.
J Appl Microbiol ; 114(3): 672-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23190078

RESUMO

AIMS: Schinus terebinthifolius leaves are used for treating human diseases caused by micro-organisms. This work reports the isolation, characterization and antimicrobial activity of S. terebinthifolius leaf lectin (SteLL). METHODS AND RESULTS: The isolation procedure involved protein extraction with 0.15 mol l(-1) NaCl, filtration through activated charcoal and chromatography of the filtrate on a chitin column. SteLL is a 14-kDa glycopeptide with haemagglutinating activity that is inhibited by N-acetyl-glucosamine, not affected by ions (Ca(2+) and Mg(2+)) and stable upon heating (30-100 °C) as well as over the pH 5.0-8.0. The antimicrobial effect of SteLL was evaluated by determining the minimal inhibitory (MIC), bactericide (MBC) and fungicide (MFC) concentrations. Lectin was active against Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella enteritidis and Staphylococcus aureus. Highest bacteriostatic and bactericide effects were detected for Salm. enteritidis (MIC: 0.45 µg ml(-1)) and Staph. aureus (MBC: 7.18 µg ml(-1)), respectively. SteLL impaired the growth (MIC: 6.5 µg ml(-1)) and survival (MFC: 26 µg ml(-1)) of Candida albicans. CONCLUSIONS: SteLL, a chitin-binding lectin, purified in milligram quantities, showed antimicrobial activity against medically important bacteria and fungi. SIGNIFICANCE AND IMPACT OF THE STUDY: SteLL can be considered as a new biomaterial for potential antimicrobial applications.


Assuntos
Anacardiaceae/química , Anti-Infecciosos/farmacologia , Extratos Vegetais/farmacologia , Lectinas de Plantas/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hemaglutinação , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Folhas de Planta/química , Lectinas de Plantas/isolamento & purificação
15.
J Laryngol Otol ; 137(5): 490-495, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35780767

RESUMO

OBJECTIVE: There is no consensus in the literature regarding the relationship between high-resolution computed tomography findings and hearing thresholds in pure-tone audiometry in otosclerosis. This study evaluated the association between high-resolution computed tomography findings and pure-tone audiometry in otosclerosis in the spongiotic phase. METHODS: A cross-sectional study was conducted of 57 ears with surgically confirmed stapes fixation and tomographic findings. Air conduction and bone conduction thresholds on audiometry, and air-bone gap, were analysed. RESULTS: There were no correlations between sites affected by otospongiosis and air conduction threshold, bone conduction threshold or air-bone gap in the analysed tomographic images, but the diameter of the otospongiotic focus was greater in the presence of extension of the otospongiotic foci to the cochlear endosteum. CONCLUSION: There were no relevant associations between high-resolution computed tomography findings and pure-tone audiometric measurements. However, the diameter of the otospongiotic focus was greater in the presence of extension of the otospongiotic foci to the cochlear endosteum.


Assuntos
Otosclerose , Cirurgia do Estribo , Humanos , Audiometria de Tons Puros/métodos , Otosclerose/diagnóstico , Otosclerose/diagnóstico por imagem , Estudos Transversais , Audiometria , Tomografia Computadorizada por Raios X , Audição , Condução Óssea , Cirurgia do Estribo/métodos , Limiar Auditivo , Estudos Retrospectivos
16.
Scand J Immunol ; 76(6): 567-72, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22946764

RESUMO

The mitogenic lectins are invaluable tools to study the biochemical changes associated with lymphocyte activation and proliferation of various immune cells. Rachycentron canadum lectin (RcaL) was detected and purified from serum of cobia fish. The aim of this study was to evaluate the proliferative response and cytokine production in splenocytes of mice in vitro stimulated with RcaL lectin; Canavalia ensiformis lectin (Con A) was used as positive control. A high proliferation index was induced by RcaL in relation to control cells. Furthermore, RcaL induced higher IL-2 and IL-6 production in relation to control. The cell viability was 90% in splenocytes treated with RcaL lectin, but RcaL promoted significant late apoptosis after 24 and 48 h in relation to control. RcaL induced proliferative responses suggesting that this lectin can be used as a mitogenic agent in immunostimulatory assays.


Assuntos
Lectinas/farmacologia , Mitógenos/farmacologia , Baço/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Imunização , Técnicas Imunológicas , Interleucina-2/metabolismo , Interleucina-6/metabolismo , Lectinas/sangue , Lectinas/isolamento & purificação , Camundongos , Camundongos Endogâmicos BALB C , Perciformes/sangue , Lectinas de Plantas/farmacologia , Baço/imunologia
17.
Opt Lett ; 37(16): 3450-2, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23381287

RESUMO

A spatial optical filter based on splice misalignment between optical fibers with different diameters is proposed for gas refractometry. The sensing head is formed by a 2 mm long optical fiber with 50 µm diameter that is spliced with a strong misalignment between two single-mode fibers (SMF28) and interrogated in transmission. The misalignment causes a Fabry-Perot behavior along the reduced-size fiber and depending on the lead-out SMF28 position, it is possible to obtain different spectral responses, namely, bandpass or band-rejection filters. It is shown that the spatial filter device is highly sensitive to refractive index changes on a nitrogen environment by means of the gas pressure variation. A maximum sensitivity of -1390 nm/RIU for the bandpass filter was achieved. Both devices have shown similar temperature responses with an average sensitivity of 25.7 pm/°C.

18.
Eur J Clin Microbiol Infect Dis ; 31(8): 2011-6, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22240854

RESUMO

In this study, we associated the restriction modification (RM) tests to the polymerase chain reaction (PCR) detection of molecular markers (SCCmec III, seh, agr II-SCCmec IV, and lukSF) for revealing the main methicillin-resistant Staphylococcus aureus (MRSA) clones circulating in Brazil. This simple and rapid approach allowed a precise classification of the MRSA analyzed when compared with pulsed-field gel electrophoresis (PFGE) data.


Assuntos
Enzimas de Restrição-Modificação do DNA , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Tipagem Molecular/métodos , Reação em Cadeia da Polimerase/métodos , Infecções Estafilocócicas/microbiologia , Brasil , Análise por Conglomerados , Eletroforese em Gel de Campo Pulsado , Humanos , Staphylococcus aureus Resistente à Meticilina/genética
19.
J Periodontal Res ; 47(6): 695-700, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22537145

RESUMO

BACKGROUND AND OBJECTIVE: A report describing the software Dental Image Analyzer (DIA) was published in this journal in 2009. A new function - measurement of the periodontal intrabony defect angle - was added to the software in 2010. The purpose of this study was to investigate whether measurements of the radiographic intrabony defect angle using digital radiographs and the newly developed DIA tool were comparable with measurements obtained using the conventional protractor method. MATERIAL AND METHODS: The baseline radiographic defect angle of intrabony defects was measured conventionally, using a protractor, in 60 selected teeth from 47 patients and then digitally using the newly developed DIA tool. The measurements were made independently by four experienced dentists. The radiographic defect angle of intrabony defects was measured after the three anatomical landmarks were identified, namely the cemento-enamel junction, the top of the crest and the bottom of the defect. RESULTS: Both methods showed a high interexaminer reliability for measurements of the radiographic defect angle of intrabony defects (intraclass correlation coefficient > 0.97). Moreover, both methods showed high reliability (intraclass correlation coefficient > 0.96). On the other hand, the new DIA tool, compared with the conventional method, exhibited high sensitivity (0.92) and high specificity (0.91) in selecting defects of ≥ 37° or < 37°. Analysis of the time taken for measurements revealed significant differences between the two methods, with the protractor method being more time consuming. CONCLUSIONS: This study provided evidence for the lack of a significant difference between the conventional method and the DIA tool for radiographic measurement of intrabony defects. However, digital analysis was significantly faster.


Assuntos
Perda do Osso Alveolar/diagnóstico por imagem , Periodontite Crônica/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/instrumentação , Radiografia Dentária Digital/instrumentação , Adulto , Precisão da Medição Dimensional , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatísticas não Paramétricas
20.
Artigo em Inglês | MEDLINE | ID: mdl-22675382

RESUMO

Libidibia ferrea has been used in folk medicine throughout Brazil, and this study evaluated the biological activities of crude extract (CE) as well as a partially purified fraction (F80) obtained from its pods. Results from the MTT assay revealed that only F80 inhibited NCI-H292 cell growth; however, neither CE nor F80 reduced HEp-2 cell growth or sarcoma 180 tumor weight with the in vivo assay. Acute oral toxicity of the extract and fraction was evaluated following the steps of Guideline 423, using female mice; LD(50) for both preparations was determined as 2,500 mg/kg body weight. CE and F80 promoted a reduction of the leukocyte number and nitrite level in inflammatory exudates when the anti-inflammatory assay (carrageenan-induced peritonitis) was performed. CE and F80 inhibited writhing regarding antinociceptive activity (acetic acid-induced writhing response in mice). In conclusion, CE and F80 have no significant cytotoxic or antitumor activities in cell lines showing low toxicity and no action against tumors in vivo. Both preparations revealed anti-inflammatory and antinociceptive activities, corroborating the pharmacological basis of L. ferrea for ethnomedical use.

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