140 research outputs found
Antifungal Activity of Two Root Canal Sealers against Different Strains of Candida
Introduction: Microorganisms and microbial products are the main etiologic factors in pulp and periapical diseases. The present study aimed to compare the antifungal activity of two different sealers, AH-26 and MTA Fillapex against three strains of Candida, 24, 48, 72 h and 7 days after mixing. Methods and Materials: The microorganisms used in this study were Candidia albicans (ATCC 10231), Candidia glabrata (ATCC 90030) and Candidia krusei (DSM 70079). This test was based on growth of microorganisms and turbidity measurement technique using a spectrophotometer. The direct contact test was conducted by direct and indirect methods. Multiple comparisons were carried out using analysis of variances (ANOVA) with repeated measures followed by Tukey’s tests. Results: The antifungal activity of both sealers was similar in the indirect method. The antifungal activity of both sealers in the direct method was similar against Candida albicans and higher for AH-26 sealer against Candida krusei and Candida glabrata. Conclusion: The total antifungal effect of MTA Fillapex sealer was significantly less than AH-26 sealer in direct method. The antifungal effect of both sealers was similar in indirect method.Keywords: Antifungal; Antimicrobial; Candida; Endodontic Sealer
Antibacterial Activity of MTA Fillapex and AH 26 Root Canal Sealers at Different Time Intervals
Introduction: The main goal of endodontic treatment is elimination of bacteria and their by-products from infected root canals. This study compared the antibacterial effect of two different sealers, AH 26 and MTA Fillapex, on 4 microorganisms 24, 48 and 72 h and 7 days after mixing. Methods and Materials: The microorganisms used in this study consisted of Lactobacillus acidophilus (ATCC 4356), Lactobacillus casei (ATCC 39392), Staphylococcus aureus (ATCC 25923) and Enterococcus faecalis (ATCC 29212). This test is based on the growth of bacteria and turbidity measurement technique using a spectrophotometer, and direct contact was conducted. Multiple comparisons were carried out using repeated-measures ANOVA followed by Tukey’s test and student’s t-test. The level of significance was set at 0.05. Results: The antibacterial activity in the indirect technique was more than the technique with both sealers. In the direct technique the antibacterial activity on all microorganisms were higher for MTA Fillapex sealer. In the indirect technique, both sealers exhibited similar antibacterial properties. Conclusion: The antibacterial effect of MTA Fillapex sealer was significantly more than that of AH 26 sealer in the direct technique. The antibacterial effects of both sealers were similar in the indirect technique.Keywords: Antibacterial; Enterococcus faecalis; Lactobacillus; MTA Fillapex; Sealers; Staphylococcu
In vitro evaluation of the sealing ability of three newly developed root canal sealers: A bacterial microleakage study
The purpose of this study was to compare the sealing ability of MTA Fillapex, Apatite Root Canal Sealer and AH26 sealers.
The present in vitro study was carried out on 142 extracted single-rooted human mature teeth. The teeth were randomly divided into three experimental groups (n=44) and two control groups (n=5). Three root canal sealers were MTA Fillapex, Apatite Root Canal Sealer and AH26. The teeth in the control groups were either filled with no sealer or made completely impermeable. The root canals were prepared and obturated with gutta-percha and one of the sealers. The teeth were sterilized with ethylene oxide gas prior to the bacterial leakage assessment using Enterococcus faecalis. Leakage was evaluated every 24 hours for 90 days. Data were analyzed with descriptive statistical methods and chi-squared test. If the data were significant, a proper post hoc test was used. Statistical significance was set at P<0.05.
The positive control specimens exhibited total bacterial penetration whilst the negative control specimens showed no evidence of bacterial penetration. At the end of the study, the analysis of microleakage with chi-squared test showed no significant differences between the experimental groups (P<0.05). The results of chi-squared test analyzing the pair-wise differences between the groups considering the numerical values for leakage day indicated the lowest leakage with AH26 and the highest with Apatite root sealer.
According to the results of the present study, sealing ability of AH26 was significantly higher than that of MTA Fillapex and Apatite Root Canal Sealer
Efecto sinérgico del enjuague bucal persica y del extracto etanólico iraní de propolis contra la formación de biofilm de patógenos orales (estudio in vitro)
This study was granted by Drug Applied
Research Center, Tabriz University of
Medical Sciences and approved by
Tabriz University of Medical Sciences.
Author Thank all staff of Biomedicine
(Medical Biology) Research Institute.Aims: Several pathogens are responsible for oral diseases and dental plaque and their main mechanism
is biofilm production. Natural products are point of interest for controlling these infections. persica
mouthrinse, propolis and honey are some of these products with considerable antibacterial effects. In
this study, we aimed to investigate synergy effect of these products on their antibiofilm and antibacterial
effect.
Material and Methods: Minimal Inhibitory effect and Minimial Biofilm inhibitory concentration of persica
mouthrinse, propolis, honey solely and in combination was calculated against Streptococcus mutans
ATCC35668, methicillin-resistant Staphylococcus aureus ATCC 33591, Staphylococcus aureus ATCC 29213,
Staphylococcus epidermidis, Enterococcus faecalis ATCC 29212 , Escherichia coli ATCC 25922.
Results: Combination of persica and propolis had a better profile in biofilm's inhibition than honey.
None of herbal combinations had synergistic effect against studied bacteria; MIC of the persica mouth
had the best effect against Streptococcus mutans, which causes caries.
Conclusions: There was no synergistic effect of persica and propolis and the best antimicrobial effect
was observed on subminimum inhibitory concentration of persica mouthwash. Findings of the present
study suggest use of other combination than honey, propolis and persica for improving antimicrobial
activity of these components.Objetivos: Varios patógenos son responsables de enfermedades orales y la placa dental y su mecanismo
principal es la producción de biofilm. Los productos naturales son puntos de interés para controlar estas
infecciones. persica mouthrinse, propolis y miel son algunos de estos productos con considerables efectos
antibacterianos. En este estudio, se buscó investigar el efecto sinérgico de estos productos sobre su
antibiótico y efecto antibacteriano.
Material y Métodos: Se calculó el efecto inhibidor mínimo y la concentración inhibitoria mínima de biofilm
de enjuague bucal de persica, propóleos, miel únicamente y en combinación, contra Staphylococcus
aureus ATCC 29213, S. epidermidis, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922.
Resultados: La combinación de persica y propóleo tuvo un mejor perfil en la inhibición de la biopelícula
que la miel. Ninguna de las combinaciones de hierbas tuvo efecto sinérgico contra las bacterias estudiadas;
La Se calculó el efecto inhibidor mínimo de la boca de la persica tuvo el mejor efecto contra Streptococcus
mutans, que causa la caries.
Conclusiones: No hubo efectos sinérgicos de la persica y el propóleo y se observó el mejor efecto antimicrobiano
en la concentración mínima inhibitoria de enjuague bucal de persica. Los hallazgos del presente estudio sugieren el uso de otra combinación que la miel,
el propóleo y la persica para mejorar la actividad antimicrobiana
de estos componentes
Ruta sencilla para la preparación de hidrogeles sensibles al pH mediante el uso de proteínas de clara huevo en soporte de alginato para la encapsulación de probióticos
Aims: In the present study, we evaluated the use of egg white proteins in alginate scaffolds and calcium
alginate for the formulation of Lactobacillus casei and Lactobacillus acidophilus in the stomach acidic conditions.
Material and Methods: after microorganism’s encapsulation in egg white proteins in alginate, survival
assays and release in different conditions were evaluated. Scanning electron microscope and Fourier-
transform infrared spectroscopy were used for analysis.
Results: The results showed the high potential of this type of formulation in protecting the probiotics
from stomach acidic conditions that is due to the significant increase in survival of the bacteria. Our
study showed that the viability of the L. casei to free L. acidophilus had much less, however, with the encapsulation
of the bacteria Egg white proteins in Alginate increased their survival significantly. Specially
for the L. casei. Swelling and shrinkage behavior of egg white proteins in alginate capsules in different
pH showed that the swelling of the capsule in the distilled water in the neutral terms had more inflationcapacity
than similar position in terms of gastric acidity.
Conclusions: the use of egg white proteins-Alginate for encapsulation of probiotics enhanced the stability
of these microorganisms in simulated gastric environments adverse conditions.Objetivos: En el presente trabajo se comparó el uso de proteínas de clara de huevo en soporte de alginato
y alginato de calcio para la formulación.
Material y Métodos: Tras la encapsulación de microorganismos en proteínas de clara de huevo en alginato,
se evaluaron ensayos de supervivencia y liberación en diferentes condiciones. Para el análisis se
han utilizado la microscopio electrónico con escáner y la espectroscopia infrarroja de transformada de
Fourier.
Resultados: Los resultados muestran el alto potencial de este tipo de formulación en la protección de los
probióticos frente a las condiciones ácidas del estómago, por el aumento significativo en la supervivencia
de las bacterias. Nuestro estudio demostró que la viabilidad de L. casei y L. acidophilus era mucho menor,
sin embargo, con la encapsulación de las bacterias con proteínas de clara de huevo en alginato aumentaron
significativamente su supervivencia especialmente para L. casei. La hinchazón y el comportamiento
de contracción de las proteínas de clara de huevo en cápsulas de alginato en diferentes pH mostraron que la hinchazón de la cápsula en el agua destilada en términos neutros tenía más capacidad de inflación que una posición similar en términos de acidez gástrica.
Conclusion: el uso de proteínas de clara de huevo-alginato para la encapsulación de probióticos mejora la estabilidad de estos microorganismos en condiciones adversas simuladas del medio gástrico.This study was granted by Drug Applied
Research Center, Tabriz University of
Medical Sciences and approved by
Tabriz University of Medical Sciences.
Author Thank all staff of Biomedicine
(Medical Biology) Research Institute
Frequency of bap and cpaA virulence genes in drug resistant clinical isolates of Acinetobacter baumannii and their role in biofilm formation
Objective(s): Acinetobacter baumannii has a high propensity to form biofilm and frequently causes medical device-related infections with multiple-drug-resistance in hospitals. The aim of this work is to study antimicrobial resistance and the role of bap and cpaA genes in biofilm formation by A. baumannii to understand how this pathogen persists in the hospital environment. Materials and Methods: Theantibiotic resistance profile and in vitro biofilm-forming ability of one hundred clinical isolates of A. baumannii was evaluated by disc diffusion and crystal-violet staining methods, respectively. Isolates were tested for the presence of bap and cpaA genes. Results: The isolates were highly resistant to cefepime, third-generation cephalosporins, ciprofloxacin, cotrimoxazole, aminoglycosides and carbapenems. Moreover, four isolates were resistant to colistin. Quantification of biofilm showed that 43% of the isolates were strong biofilm-producer. Furthermore, 32% of the isolates exhibited moderate biofilm-formation and showed initial binding activity. Frequency of bap and cpaA were determined 92% and 36%, respectively. Conclusion: There was strong association between the presence of bap gene and biofilm formation by A. baumannii isolates (P=0.003). In addition, multidrug resistant isolates produced stronger biofilm than other isolates (P=0.0001). These results indicate importance of biofilm in resistance of isolates and effect of presence of bap gene in biofilm formation by A. baumannii strains
Formulation of Menthol-Loaded Nanostructured Lipid Carriers to Enhance Its Antimicrobial Activity for Food Preservation
Purpose: Due to the
antimicrobial property, menthol have significant potential for food
preservation and foodstuff shelf life improvement. Nevertheless, menthol
instability, insolubility, and rapid crystallization in aqueous media make it
unsuitable for used in food products. This work was aimed to prepare
menthol-loaded nanostructured lipid carriers (NLCs) to enhance its
antimicrobial activity.
Methods: Morphology,
particle size and size distribution, encapsulation efficiency percent (EE%),
and physical stability of the optimized formulation, prepared by hot melt
homogenization method, were characterized by scanning electron microscopy,
particle size analyzing, gas chromatography, and X-ray diffraction (XRD)
methods. Minimum inhibitory concentration and minimum bactericidal
concentration of menthol-loaded NLCs were evaluated and compared with
conventional menthol emulsion against various Gram-positive (Staphylococcus
aureus, Bacillus cereus) and Gram-negative bacteria (Escherichia coli),
as well as one fungus (Candida albicans).
Results: Menthol-loaded
NLCs were spherically shaped nanosized (115.6 nm) particles with narrow size
distribution (PDI = 0.2), suitable menthol EE% (98.73%), and appropriate
physical stability after 90 days of storage period. XRD results indicated that
menthol was in the amorphous form in the nanoparticles matrix. Antibacterial
assay results revealed that the menthol-loaded NLCs exhibited significantly
higher in vitro antimicrobial property than conventional menthol
emulsion. The results also indicated that menthol-loaded NLCs had better effect
on fungi than bacteria, and furthermore, antibacterial efficiency on
Gram-positive bacteria was higher than Gram-negative bacteria.
Conclusion: In conclusion,
NLCs could be a promising carrier for improvement of antimicrobial activity and
preservation efficacy of essential oils in foodstuffs
Efecto inhibidor de Lactobacillus aislado de la cavidad oral contra patógenos bacterianos y su efecto en la promoción de la salud
Aims: To determine the inhibitory effect of oral Lactobacillus against bacterial pathogens and investigate
correlation between presence of Lactobacillus strains and health promotion.
Method: One hundred saliva samples were collected from oral cavity of domestic dairy consumers and
were investigated for the isolation and identification of Lactobacillus strain by conventional culture and
sequencing of 16SrRNA. Furthermore, well diffusion assay was performed to determination of antibacterial
activity of Lactobacillus strains against bacterial pathogens including Salmonella typhimurium, Klebsiella
pneumoniae, Shigella sonnei, Shigella dysenteriae, Enterococcus faecalis and Enterococcus faecium. Finally,
association between health condition and isolation of Lactobacillus were investigated and obtained data
using questionary form were analysed by chi-square test.
Results: Thirty Lactobacillus strains recovered from 100 hundred saliva samples. The
most common isolated strain was L. gasseri (n=18) and followed by L. vaginalis (n=3) and
L. salivarius (n=3). All Lactobacillus strains demonstrated antibacterial activity against at
least one of the investigated pathogens. However, the strongest results were obtained by L. vaginalis
against K. pneumonia. The correlation between the presence of thirty Lactobacillus strains and health promotion
not found. However, only L. gasseri species has significant positive impact on health in their hosts
(P < 0.05).
Conclusion: Only some Lactobacillus species have a positive impact on health promotion. Despite of
weak activity against the investigated pathogens, L. gasseri has a positive impact on the mental problem
(intense anger and depression) of their hosts.Objetivos: Determinar el efecto inhibidor del Lactobacillus aislado de la cavidad oral contra patógenos
bacterianos e investigar la correlación entre la presencia de cepas de Lactobacillus y la promoción de la
salud.
Método: se recolectaron cien muestras de saliva de la cavidad oral de consumidores de productos lácteos
y se investigó el aislamiento e identificación de la cepa de Lactobacillus mediante cultivo convencional y
secuenciación de 16SrRNA. Además, se realizó un ensayo de difusión en pocillos para determinar la actividad
antibacteriana de las cepas de Lactobacillus contra patógenos bacterianos que incluyen Salmonella
typhimurium, Klebsiella pneumoniae, Shigella sonnei, Shigella dysenteriae, Enterococcus faecalis y Enterococcus
faecium. Finalmente, se investigó la asociación entre el estado de salud y el aislamiento de Lactobacillus y
se obtuvieron los datos utilizando el cuestionario mediante la prueba de chi-cuadrado.
Resultados: Se aislaron treinta cepas de Lactobacillus de 100 muestras de saliva. La cepa aislada más
común fue L. gasseri (n = 18), seguida por L. vaginalis (n = 3) y L. salivarius (n = 3). Todas las cepas de
Lactobacillus demostraron actividad antibacteriana contra al menos uno de los patógenos investigados. Sin embargo, los resultados más fuertes fueron obtenidos por L.
vaginalis contra K. pneumonia. No se encontraron correlación entre
la presencia de algunas de las treinta cepas de Lactobacillus y la
promoción de la salud. Sin embargo, solo la especie L. gasseri tuvo
un impacto positivo significativo en la salud de sus hospedadores
(P <0,05).
Conclusión: solo algunas especies de Lactobacillus tienen un impacto
positivo en la promoción de la salud. A pesar de la actividad
débil contra los patógenos investigados, L. gasseri tiene un impacto
positivo en el problema mental (ira intensa y depresión) de sus
huéspedes
Diversity of Bacteroidaceae family in gut microbiota of patients with chronic kidney disease and end stage renal disease
Background: Human intestine microbiota are known to be directly and indirectly altered during some diseases such as kidney complications. Bacteroides is considered as the main and the most abundant phylum among human gut microbiota, which has been classified as enterotype 1. This study aimed to assess the abundance of Bacteroides spp. in fecal flora of end-stage renal disease (ESRD) and chronic kidney disease (CKD) patients and compare it with the Bacteroides composition among fecal flora of healthy individual. Methods: Fresh fecal samples were collected from 20 CKD/ESRD patients and 20 healthy individual without any kidney complications. The pure microbial DNA was extracted by QIAamp Stool Mini Kit from stool samples. MiSeq system was used to analyze the intestinal composition by next generation sequencing method. Results: A number of 651 bacterial strains were isolated and identified from 40 fecal samples of both patients and healthy groups. Bioinformatics analysis defined 18 different types of Bacteroides species which included 2.76% of all strains. Statistical analysis showed no significant difference between study groups (P>0.05). In both healthy and patient groups three species including B. dorei, B. uniformis, and B. ovatus have allocated the most abundance to themselves. The lowest abundance was related to B. eggerthii, A. furcosa and B. barnesiae among CKD/ESRD patients and A. furcosa, B. barnesiae, and B. coprocola had the lowest abundance among healthy people. Conclusion: This study indicates despite all previous evidence of Bacteroides role in gut microbiota, it had no different distribution between healthy persons and CKD/ESRD patients
Inmovilización y microencapsulación de Lactobacillus caseii y Lactobacillus plantarum usando base de zeolita y evaluando su viabilidad en condiciones simuladas de gastroesofágico-intestino
This study was supported by Drug Applied
Research Center, Tabriz University
of Medical Sciences. All experiences
were done in Microbiology laboratory
of Drug Applied Research Center. We
thank general laboratory staff and Mr.
Vatankhah for his collaboration.Aims: In order to improve survival in gastrointestinal conditions, probiotic bacteria, i.e. we developed
a new encapsulation method of probiotics based on zeolite and by calcium-alginate zeolite-starch as an
effective method for safer delivery of probiotics.
Material and Methods: Lactobacillus casei (ATCC 39392) and Lactobacillus plantarum (ATCC 29521) were
used as probiotics. After microorganism’s immobilization on zeolite base, encapsulation was done by
calcium-alginate zeolite-starch with the extrusion method. Afterwards, they were incubated in the simulated
gastric and intestinal condition. Viability of these bacteria was calculated on the basis of time required
to reduce the logarithmic base in the microbial population. SEM techniques were used to study
the appearance of the capsules.
Results: after incubation for 120 min under simulated gastric condition and 180 min in intestinal juice
conditions (pH=8.2), the count of alive L. casei and L. plantarum cells were 6.3 log cfu/ml and 7.3 log cfu/
ml. However, for controlling the cells, this value was zero and 2.1 log cfu/ml respectively.
Conclusion: According to the results, we had an increase of the survival rate of L. casei and L. plantarum
in gastroesophageal-intestine simulated condition. These results indicated good efficacy and high performance
of zeolite for immobilization and microencapsulation of probiotics.Objetivos: Para mejorar la supervivencia en condiciones gastrointestinales de las bacterias probióticas,
hemos desarrollado un nuevo método de encapsulación de probióticos a base de zeolita y almidón de
zeolita de alginato de calcio como método eficaz para la administración más segura de probióticos.
Material y métodos: se utilizaron Lactobacillus casei (ATCC 39392) y Lactobacillus plantarum (ATCC 29521)
como probióticos. Después de la inmovilización del microorganismo en la base de zeolita, la encapsulación
se realizó mediante zeolita-almidón de alginato de calcio con el método de extrusión. Posteriormente,
se incubaron en la condición gástrica e intestinal simulada. La viabilidad de estas bacterias se
calculó sobre la base del tiempo requerido para reducir la base logarítmica en la población microbiana.
Las técnicas SEM se usaron para estudiar la apariencia de las cápsulas.
Resultados: después de la incubación durante 120 minutos bajo condición gástrica simulada y 180 minutos
en condiciones de jugo intestinal (pH = 8,2), el recuento de células vivas de L. casei y L. plantarum
fue de 6,3 log ufc / ml y de 7,3 log ufc / ml. Sin embargo, para controlar las células, este valor era cero y
2,1 log cfu / ml respectivamente.
Conclusión: De acuerdo con los resultados, tuvimos un aumento
de la tasa de supervivencia de L. casei y L. plantarum en condiciones
simuladas de gastroesofágico-intestino. Estos resultados indicaron
buena eficacia y alto rendimiento de zeolita para inmovilización y
microencapsulación de probióticos
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