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1.
Article in English | MEDLINE | ID: mdl-34199794

ABSTRACT

Our aim was to evaluate clinical, biochemical and microbiological markers related to dental caries in adults. A sample that consisted of 75 volunteers was utilized. The presence of caries and the presence of plaque and gingival indices were determined. Unstimulated salivary flow, pH, lactate, Streptococcus mutans and Streptococcus dentisani were measured in the participants' plaque and saliva samples before and after rinsing with a sugar solution. Lactate in plaque was found to be significantly related to age, gender, tooth-brushing frequency, the presence of cavitated caries lesions and plaque and gingival indices (p < 0.05). The levels of S. dentisani in plaque increased significantly with tooth-brushing frequency (p = 0.03). Normalized plaque S. dentisani values and the percentage of S. dentisani were slightly higher in patients with basal lactic acid levels ≤ 50 mg/L. After rinsing with a sugary solution, the percentage of S. mutans levels in plaque were higher in patients with lactic acid levels > 350 mg/L (p = 0.03). Tooth-brushing frequency was the factor which was most associated with oral health. Women reflected better clinical and biochemical parameters than men. Low pH and high lactic acid levels tended to be associated with high caries rates. No association was found between bacteria levels and caries indices.


Subject(s)
Dental Caries , Adult , Dental Caries/epidemiology , Female , Humans , Male , Saliva , Streptococcus , Streptococcus mutans
2.
J Oral Sci ; 61(1): 184-194, 2019.
Article in English | MEDLINE | ID: mdl-30918216

ABSTRACT

The present study aimed to test the antimicrobial activity of Streptococcus dentisani (S. dentisani) supernatant against a collection of microorganisms implicated in dental root infections, and to analyze morphological changes induced in a selection of the tested microorganisms. A total of 22 microbial species were selected, and their growth was monitored by spectrophotometry in the presence and absence of the supernatant of S. dentisani at different assay concentrations (0.2×, 1×, 2×). The generation time and maximum growth rates were evaluated under every tested condition. Scanning electron microscope (SEM) images were obtained to assess the effect on the cell surface following incubation of the pathogens with the concentrated (2×) supernatant of S. dentisani. The supernatant of S. dentisani was found to exert effective inhibitory activity against most of the studied microorganisms implicated in dental root infections (20 out of 22). Total growth inhibition was observed in the case of Streptococcus oralis, Streptococcus sobrinus, Streptococcus salivarius, Prevotella intermedia, and Streptococcus mutans, while the rest of the microorganisms showed an increase in the generation time (between 30 min and 4 h). SEM images revealed structural changes in the membrane consistent with bacteriocin activity, although the effects were heterogeneous among the different species tested.


Subject(s)
Anti-Bacterial Agents/pharmacology , Culture Media , Dental Pulp Cavity/microbiology , Infection Control, Dental/methods , Streptococcus/chemistry , Streptococcus/drug effects , Humans , Microbial Sensitivity Tests , Microscopy, Electron, Scanning , Species Specificity , Streptococcus/growth & development , Streptococcus/ultrastructure
3.
J Oral Microbiol ; 10(1): 1495975, 2018.
Article in English | MEDLINE | ID: mdl-30181819

ABSTRACT

This study aimed to compare the bacterial viability and diversity of a substrate-formed biofilm (SF-biofilm) in situ to a supragingival tooth-formed biofilm (TF-biofilm) in the same group of individuals. The impact of the device/disc position and toothbrushing during the formation of SF-biofilm was also assessed. Two tests were run. In test 1, 15 volunteers wore two hemi-splints carrying six discs of human enamel, glass, and hydroxyapatite for 2 days, and were instructed to not perform any oral hygiene measure. Biofilm samples were collected from the substrates and the contralateral tooth and were analysed using CLSM. In five volunteers, half of the biofilm present on the discs and their contralateral teeth were scraped and analysed using 16S  pyrosequencing. In test 2, the microscopic analysis was repeated only on the SF-biofilm samples, and the volunteers were allowed to brush their teeth. Multivariate analyses revealed that the donors had a significant effect on the composition of the biofilm, confirming its subject-dependent character. The bacterial composition of the SF-biofilm was similar to the TF-biofilm, with significant differential abundance detected in very few taxa of low abundance. The toothbrushing during the formation of SF-biofilm was the only factor that conditioned the thickness or bacterial viability.

4.
Rev. colomb. cienc. pecu ; 31(1): 17-25, ene.-mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-978238

ABSTRACT

Abstract Background: Abnormal and stereotypic behaviors in horses have been widely studied around the world and different epidemiological situations have been described for behavioral disturbances. Objective: To determine the frequency of abnormal and stereotypic behaviors in a population of police patrolling horses. Additionally, to establish chronic stress levels in the population of interest. Methods: Twenty police horses were evaluated. The animals went through 48 hours of continuous observation to record the frequency of normal, abnormal, and stereotypic behaviors. Cortisol index (CI) was calculated for all the subjects. Results: A 65% of the horses expressed behavioral disturbances, with 55% corresponding to stereotypies. The abnormal behaviors consisted on wood chewing, pawing, and bed eating. Stereotypic behaviors were weaving, stall walking, and aerophagia (crib-biting or wind sucking). According to the CI, 13 horses were under chronic stress (CI<0.30). Conclusion: High level of chronic stress, expressed as abnormal and stereotypic behaviors, was observed in the horses.


Resumen Antecedentes: Los comportamientos anormales y estereotipados en caballos han sido ampliamente estudiados en el mundo, así como también diversas situaciones epidemiológicas relacionadas con estos disturbios. Objetivo: Determinar la frecuencia de los comportamientos anormales y estereotipados en una población de caballos de patrullaje de la policía y establecer su nivel de estrés crónico. Métodos: Se evaluaron 20 caballos. Los animales fueron observados durante 48 horas continuas para recopilar los comportamientos anormales y estereotipados. El índice del cortisol (CI) fue calculado para todos los animales. Resultados: El 65% de la población estudiada expresó disturbios del comportamiento, y el 55% de dichos disturbios se clasificó como estereotipias. Los comportamientos anormales observados consistieron en lignofagia, patear y comer cama. Los comportamientos estereotipados fueron balanceo, caminar en círculos y aerofagia. El CI mostró presencia de estrés crónico en 13 caballos (CI<0.30). Conclusión: Se encontró un alto porcentaje de estrés crónico en los caballos de la policía, expresado como comportamientos anormales y estereotipados.


Resumo Antecedentes: Comportamentos anormais e estereotipados de cavalos têm sido amplamente estudados no mundo, assim como também diversas situações epidemiológicas relacionadas com estes distúrbios. Objetivo: Determinar a frequência de comportamentos anormais e estereotipados em uma população de cavalos de patrulhamento da polícia e estabelecer seu nível de estresse crónico. Métodos: Foram avaliados 20 equinos. Os animais foram observados durante 48 horas continuas para gravar os comportamentos anormais e estereotipados. O índice do cortisol (CI) foi calculado para todos os equinos. Resultados: O 65% da população estudada expressaram distúrbios do comportamento, 55% dos distúrbios foram estereotipias. Os comportamentos anormais observados foram lignofagia, escoicear a baia e comer cama. Os comportamentos estereotipados foram movimentos laterais repetitivos, movimentos aleatórios na baia e aerofagia. O CI mostrou presença de estresse crónico em 13 cavalos ao mostrar valores menores a 0.30. Conclusão: Se determinou um alto porcentagem de estresse crónico nos cavalos da polícia, expressado na forma de comportamentos anormais e estereotipados.

5.
Endodoncia (Madr.) ; 34(1): 32-41, ene.-mar. 2016. ilus
Article in Spanish | IBECS | ID: ibc-156842

ABSTRACT

La terapia fotodinámica (TFD) es un procedimiento terapéutico con capacidad antimicrobiana demostrada en la literatura científica. Esta constatado que su empleo, después de la preparación químico-mecánica convencional, reduce la carga microbiana en el diente necrótico. Esto supone una ventaja en los casos de necrosis en dientes con anatomías complejas, como cuando existe un istmo. Por otro lado, la TFD podría ser una alternativa al empleo de medicaciones intraconducto en los dientes con patología periapical. El propósito de este articulo es describir la técnica de uso de la TDF, empleando una lámpara de diodos LED de baja potencia (FotoSan®) como fuente lumínica y azul de toluidina como fotosensibilizador, y mostrar los resultados de su asociación con el tratamiento endodóncico convencional, en un caso de un primer molar mandibular con istmo permeable, necrosis pulpar y periodontitis apical crónica


Photodynamic therapy (PDT) has been shown to exert antimicrobial action. Following conventional chemical-mechanical preparation, PDT reduces the microbial burden in the necrotic tooth. This implies an advantage in cases of necrosis in teeth with complex anatomical features, such as the presence of an isthmus. On the other hand, PDT could constitute an alternative to the use of drugs within the canal of teeth with periapical disease. This study describes the PDT technique using a low-power LED lamp (FotoSan®) as light source and toluidine blue as photosensitizer. A description is provided of the results obtained on combining the technique with conventional endodontic treatment of a first mandibular molar with a permeable isthmus, pulp necrosis and chronic apical periodontitis


Subject(s)
Humans , Male , Adult , Dental Pulp Necrosis/drug therapy , Periapical Periodontitis/drug therapy , Root Canal Therapy/instrumentation , Photochemotherapy , Diagnosis, Differential , Molar
7.
APMIS ; 123(5): 427-32, 2015 May.
Article in English | MEDLINE | ID: mdl-25858184

ABSTRACT

To identify the bacterial diversity (microbiota) in expectorated sputum, a pyrosequencing method that investigates complex microbial communities of expectorated sputum was done in 19 stable chronic obstructive pulmonary disease patients (mean (SD) FEV1: 47 (18%) of predicted value). Using conventional culture, 3 phyla and 20 bacterial genera were identified, whereas the pyrosequencing approach detected 9 phyla and 43 genera (p < 0.001). In sputum the prevalent genera with pyrosequencing approach were Streptococcus, Actinomyces, Neisseria, Haemophilus, Rothia, Fusobacterium, Gemella, Granulicatella, Porphyromonas, Prevotella and Veillonella. Enterobacteriaceae, detected frequently in conventional culture, were not significantly detected with pyrosequencing methods. In addition, we found that important pathogens such as Haemophilus and Moraxella were detected more frequently with the new genetic procedures. The presence of Enterobacteriaceae is probably overestimated with conventional culture, whereas other difficult cultivable pathogens are underestimated. These studies open a new perspective for evaluating the role of bacterial colonization in chronic obstructive pulmonary disease pathogenesis and progression.


Subject(s)
Microbiota , Pulmonary Disease, Chronic Obstructive/microbiology , Aged , Aged, 80 and over , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , Bacterial Typing Techniques/methods , DNA, Bacterial/genetics , DNA, Bacterial/isolation & purification , Female , Humans , Male , Metagenome/genetics , Microbiota/genetics , Middle Aged , Molecular Typing/methods , Polymerase Chain Reaction/methods , Prospective Studies , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics , Sputum/microbiology
8.
Opt Express ; 21(5): 5373-8, 2013 Mar 11.
Article in English | MEDLINE | ID: mdl-23482108

ABSTRACT

We introduce for the first time the concept of an information "container" before a standard optical encrypting procedure. The "container" selected is a QR code which offers the main advantage of being tolerant to pollutant speckle noise. Besides, the QR code can be read by smartphones, a massively used device. Additionally, QR code includes another secure step to the encrypting benefits the optical methods provide. The QR is generated by means of worldwide free available software. The concept development probes that speckle noise polluting the outcomes of normal optical encrypting procedures can be avoided, then making more attractive the adoption of these techniques. Actual smartphone collected results are shown to validate our proposal.

9.
Opt Lett ; 35(2): 196-8, 2010 Jan 15.
Article in English | MEDLINE | ID: mdl-20081966

ABSTRACT

We have developed a hybrid adaptive-optics visual simulator (HAOVS), combining two different phase-manipulation technologies: an optically addressed liquid-crystal phase modulator, relatively slow but capable of producing abrupt or discontinuous phase profiles; and a membrane deformable mirror, restricted to smooth profiles but with a temporal response allowing compensation of the eye's aberration fluctuations. As proof of concept, a phase element structured as discontinuous radial sectors was objectively tested as a function of defocus, and a correction loop was closed in a real eye. To further illustrate the capabilities of the device for visual simulation, we recorded extended images of different stimuli through the system by means of an external camera replacing the subject's eye. The HAOVS is specially intended as a tool for developing new ophthalmic optics elements, where it opens the possibility to explore designs with irregularities and/or discontinuities.

10.
Opt Express ; 13(3): 918-25, 2005 Feb 07.
Article in English | MEDLINE | ID: mdl-19494954

ABSTRACT

We present equilateral hyperbolic zone plates with variable focal length, which are formed as moiré patterns by a mutual rotation of two identical basic grids. Among others, all principal zone plates, except of the spherical one, can be used as these basic transmittances. Three most important advantages of the proposed moiré zone plates are: a constant aperture of the created element during the mutual movement of basic grids, lack of aberrations due to their undesired mutual lateral displacements and high diffraction efficiency of the binary phase version. To obtain clearer moiré fringe pattern, a radial carrier frequency can be added additionally to the transmittances of basic grids. The destructive interference between both arms of the focal cross of the equilateral hyperbolic moiré zone plate can be obtained by a constant phase shift introduced in the transmittances of the basic grids. Potential applications of discussed elements are indicated, including the most promising one in the three-point alignment technique.

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