ABSTRACT
Grapevine, an important horticultural crop in the world, is moderately tolerant to cold conditions and is subjected to the cold injuries at different regions. So studies on different aspects of tolerance mechanism to unexpected cold of late spring as well as winter freezing seems necessary about this vine. For this reason, study on genes responsible for acquiring cold tolerance is very important. Transcription factors are among regulatory proteins that are responsible for cold acclimation. In this research work, expression levels of CBF1, CBF2, CBF3, and CBF4 transcription factors were studied on two cvs of Vitis vinifera ("Khalili-Danedar" and "Shahroodi") as well as one Vitis riparia at different times after treating at 4 °C. Results showed that two vinifera cultivars, "Khalili-Danedar" and "Shahroodi", had similar trend for each transcription factor. Gene expression increased at the beginning of cold stress and then decreased. Expression of these TF started some minutes (CBF1) after cold treatment and continued for several hours (CBF2), even till the tenth day (CBF4). All together V. riparia which is endemic to the cold regions behaved stronger and showed higher expression for all studied transcription factors. Among two V. vinifera cultivars, "Khalili-Danedar" showed significantly higher expression compared with "Shahroodi". The comparison of expression levels of these four transcription factors revealed that the least and the greatest expressions were recorded for CBF1 and CBF3 respectively, and two CBF2 and CBF4 had approximately the same expression levels.
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In this study, the adsorption of benzoic acid and phenols in the aqueous phase by MOF-Cu adsorbent was investigated. A high-performance liquid chromatography (HPLC) device was used to analyze the concentration of contaminants in the solution. Three isotherms, Freundlich, Langmuir, and Temkin were performed for adsorption of Benzoic Acid (BA) and Phenol contaminants. Correlation factor for adsorption isotherms were fitted into Langmuir aqueous BA and Phenol would be 99.89 and 99.98%, respectively. The equilibrium adsorption capacity MOF-Cu of BA and Phenol is 636.73 and 524.42 mg/g, respectively. In this study, high contaminant adsorption with π-π interaction and hydrogen bonding leads to the high capacity of MOFCu. In addition, the increase in adsorption capacity of benzoic acid is due to the electronegative property of oxygen in the carbonyl group and the similarity of the carboxylic acid functional group with the adsorbent. The result shows, that at initial time adsorption, has been a non-linear trend. In addition, the first-order kinetic model is not a suitable option for fitting the experimental data of adsorption kinetics and the adsorption kinetics of BA and Phenol is very well compatible with the semi-second order with the correlation Factor being 99.7 and 99.78, respectively. Also, the equilibrium adsorption capacity in pseudo-second order kinetic for BA and Phenol is 613.5 and 523.56 mg/g respectively.
Subject(s)
Metal-Organic Frameworks , Water Pollutants, Chemical , Adsorption , Benzoic Acid/analysis , Hydrogen-Ion Concentration , Kinetics , Phenol/analysis , Phenol/chemistry , Phenols/analysis , Phenols/chemistry , Thermodynamics , Wastewater/chemistry , Water/analysis , Water Pollutants, Chemical/analysisABSTRACT
BACKGROUND: Instrument fracture is one of major challenges during root canal treatment. In order to reduce such errors, it seems necessary to investigate the effects of potentially impactful factors. One of such factors could be the temperature of an agitator. OBJECTIVES: This study examined the effects of different temperature of the sodium hypochlorite solution on the cyclic fatigue resistance of ProTaper Gold (PTG) rotary files. MATERIAL AND METHODS: Forty-five PTG S1 rotary files were tested in a metal block that simulated a canal curvature angle of 60° and a curvature radius of 5 mm. They were randomly divided into 3 groups of 15 according to sodium hypochlorite temperatures of 22°C (group 1), 4°C (group 2) and 37°C (group 3). Files from each group were rotated at 300 rpm in the block at each temperature. The number of cycles to fracture was calculated and the fragment length was measured. The fractured surfaces were examined by means of scanning electron microscopy (SEM). The statistical analysis was completed using the Kolmogorov-Smirnov and Kruskal-Wallis tests, and the IBM SPSS Statistics for Windows software, v. 22.0, at a significance level of 5%. RESULTS: The cyclic fatigue resistance of the PTG rotary files was not significantly affected by the temperature of sodium hypochlorite (p > 0.05). CONCLUSIONS: Increasing the temperature of sodium hypochlorite to 37°C or decreasing it to 4°C did not significantly affect the cyclic fatigue resistance of PTG rotary files.
Subject(s)
Root Canal Preparation , Sodium Hypochlorite , Equipment Failure , Gold , Humans , Nickel , Temperature , TitaniumABSTRACT
Hydrophilic nano MnO is shown to have significant stability in aqueous media for oxidation of styrene. Different catalysts have been used to synthesis styrene oxide, but MnO-CaL is considered the efficient and selective catalyst to produce styrene oxide. In general, this paper reported especial strategy for synthesis of novel nano MnO that stabilized with oleic acid in chloroform and changing nature of its stabilizer by exchanging oleic acid with lignosulfunate and displays its catalytic activity towards selective oxidation of styrene. The catalyst has shown good selectivity in oxidation of styrene by changing temperature. Finding the optimal conditions for reaction and determining the best time and temperature for achieving the ideal product and reducing the side products are among the issues discussed in this article. MnO-CaLs leads to selective oxidation of styrene to styrene epoxide at low temperature. By increasing the temperatures, benzaldehyde and partially 2-phenyl acetaldehyde are also produced as by-products. Furthermore, the nano catalyst could be recycled several times without any clear changing in activity, which makes nano catalyst economic and environmentally friendly.
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BACKGROUND: Autogenous bone graft is the gold standard for repair of bone defects. However, osteoprogenitor stem cells are suggested as an alternative treatment. Aims: To quantitatively compare bone formation in autogenous bone graft and tissue-engineered graft using digital radiography densitometry software in canine alveolar cleft model. SETTING AND DESIGN: This experimental study on animal models was conducted in Isfahan University of Medical Sciences. METHODS: Mesenchymal stem cells (MSCs) were obtained from subcutaneous adipose tissue of 4 dogs. Undifferentiated cells were incubated with a hydroxyapatite/beta-tricalcium phosphate scaffold in an osteogenic medium for 21 days. A maxillary defect simulating human alveolar cleft was created from the alveolar crest to nasal floor with 15 mm width bilaterally. Two months later, the defect was filled with autogenous bone graft harvested from tibia on one side and tissue-engineered graft from MSCs on the other side. Digital radiography was performed on days 15, 30, 45, 60, 75, and 90 after grafting. Radiographic density was calculated by the mean numeric value of pixels of the desired area ranging from 0 (darkest) to 255 (lightest) by associated software. STATISTICAL ANALYSIS USED: The data were analyzed by Statistical Package for the Social Sciences using descriptive statistics and two-way repeated-measure analysis of variance test (α = 0.05). RESULTS: Mean density measured for autogenous bone graft group was 110.72, 82.70, 75.76, 93.57, 100.22, and 100.32 in days 15, 30, 45, 60, 75, 90, respectively and 120.7, 87.62, 83.72, 92.02, 92.30, and 93.77 in stem cell group. Although the time lapse was a significant factor in two groups (P = 0.01), the results indicated that the difference between two groups was not statistically significant (P = 0.942). CONCLUSION: Tissue-engineering can be used as an alternative method in reconstruction of bony defects with predictable clinical outcomes.
Subject(s)
Radiography, Dental, Digital , Tissue Engineering , Alveolar Process , Animals , Bone Transplantation , Dogs , Humans , Models, AnimalABSTRACT
OBJECTIVE: The apical constriction (AC) and the apical foramen (AF) are the principal reference points used to determine the apical limit for instrumentation and root canal filling. AC varies in different races, and the aim of the current study was to measure and compare the distances from AC to AF and the anatomical apex (AA) in incisor and molar teeth in the Iranian population. MATERIALS AND METHODS: Forty-five roots of incisor teeth and 45 roots of molar teeth were selected randomly in Isfahan Province, Iran. If the foramen was located toward the mesial or distal side of the apex, the cut was made mesiodistally, and if it was toward the buccal or lingual side, the section was made accordingly. Roots were examined under a microscope at ×25 magnification. The distances from AC to AF and AA were then estimated using a Motic camera. Descriptive statistics were used. The independent t-test was also used to compare distances in incisors and molars, and P = 0.05 was deemed to indicate statistical significance. RESULTS: The mean distances between AC and AF were 0.847 ± 0.33 mm in incisors and 0.709 ± 0.27 mm in molars. The mean distances between AC and AA were 1.23 ± 0.39 mm in incisors and 1.01 ± 0.38 mm in molars. In an independent t-test, the distances between AC and AF differed significantly in incisors and molars (P = 0.035), but the distances between AC and AA did not (P = 0.172). CONCLUSION: The end points for root canal therapy should be 0.85 mm in incisors and 0.70 mm in molars.
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BACKGROUND: Adequate seal of the root canal is necessary to prevent recontamination and ensure the long-term clinical success. The aim of this study was to evaluate the sealing ability of ProRoot mineral trioxide aggregate (MTA), Biodentine, and Ortho MTA as the root canal obturation materials using the fluid infiltration method. MATERIALS AND METHODS: In this invitro study a total of 66 extracted human mandibular premolars were randomly divided into five groups according to the material used for the root canal obturation. Group I - ProRoot MTA (20 samples), Group II - Biodentine (20 samples), Group III - Ortho MTA (20 samples), Group IV - negative group (3 samples), and Group V-positive group (3 samples). MTA, Biodentine, and Ortho MTA were applied using a cotton-tipped K-file #30 and hand plugger into the root canals of each group. In Group 4 (negative control), no filling material was used. In Group 5 (positive control), a single gutta-percha size #40 was inserted into the root canal without using a sealer. The teeth were mounted and exposed to the fluid infiltrarion system. Statistical analysis was performed using Kruskal-Wallis test the level of significance was set at α = 0.05. RESULTS: Mean values of microleakage in MTA ProRoot, Biodentine and Ortho MTA groups were 1.83 ± 0.62, 1.95 ± 1.27 and 1.72 ± 0.83 µL in 8 minutes. No statistically significant difference was observed between the sealing ability of ProRoot MTA, Biodentine, and Ortho MTA (P = 0.091). CONCLUSION: Within the limitations of this study, microleakage values were similar to MTA ProRoot, Biodentine, and Ortho MTA using the fluid infiltration technique.
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BACKGROUND: Halitosis is the presence of unpleasant or foul smelling breath. The origin of halitosis may be related to both systemic and oral conditions, but a large percentage of cases, about 90%, is generally related to an oral cause. The aim of this study was to compare the concentration of urea and uric acid in patients with halitosis and people without halitosis. MATERIALS AND METHODS: In this case-control study, concentration of urea and uric acid was compared between two groups: (1) persons suffering halitosis (2) control group without halitosis. Each group includes fifty patients. Unstimulated saliva was collected in both groups. Then, concentration of urea, uric acid, and creatinine was determined. The results were statistically analyzed with SPSS software version 14 (SPSS Inc., Chicago, Illinois, USA) by t-test (α = 0.05). RESULTS: Results showed that salivary urea and uric acid concentration in halitosis group were significantly greater than control group (P < 0.05). Salivary creatinine concentration in halitosis group was significantly lower compared to control group (P < 0.05). Salivary urea and uric acid concentration to creatinine ratios were higher in halitosis group than control group, and significant differences between them were existed (P < 0.05). CONCLUSION: According to the results, urea and uric acid concentration show increase in patient suffering halitosis, and this increase may result in oral malodor.
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INTRODUCTION: The aim of this randomized clinical trial was to compare the histologic pulp tissue response to one-step direct pulp capping (DPC) and miniature pulpotomy (MP) with mineral trioxide aggregate (MTA) after application of dexamethasone in healthy human premolars. METHODS AND MATERIALS: Forty intact premolars from 10 orthodontic patients, were randomly chosen for DPC (n=20) or MP (n=20). In 10 teeth from each group, after exposure of the buccal pulp horn, topical dexamethasone was applied over the pulp. In all teeth the exposed/miniaturely resected pulp tissue was covered with MTA and cavities were restored with glass ionomer. Teeth vitality was evaluated during the next 7, 21, 42, and 60 days. Signs and/or symptoms of irreversible pulpitis or pulp necrosis were considered as failure. According to the orthodontic schedule, after 60 days the teeth were extracted and submitted for histological examination. The Kruskal-Wallis and Fisher's exact tests were used for statistical analysis of the data (P=0.05). RESULTS: Although dexamethasone specimens showed less inflammation, calcified bridge, pulpal blood vasculature, collagen fibers and granulation tissue formation were not significantly different between the groups (P>0.05). CONCLUSION: Topical dexamethasone did not hindered pulp healing but reduced the amount of underlying pulpal tissue inflammation after DPC and MP in healthy human premolars.
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BACKGROUND: According to the development of resistant strains of pathogenic bacteria following treatment with antimicrobial chemotherapeutic agents, alternative approaches such as lethal photosensitization are being used. The aim of this study was to evaluate the effect of visible light and laser beam radiation in conjugation with three different photosensitizers on the survival of two main periodontopathogenic bacteria including Porphyromonas gingivalis and Fusobacterium nucleatum in different exposure periods. MATERIALS AND METHODS: In this in vitro prospective study, strains of P. gingivalis and F. nucleatum. were exposed to visible light at wavelengths of 440 nm and diode laser light, Gallium-Arsenide, at wavelength of 830 nm in the presence of a photosensitizer (erythrosine, curcuma, or hydrogen peroxide). They were exposed 1-5 min to each light. Each experiment was repeated 3 times for each strain of bacteria. Data were analyzed by two-ways ANOVA and least significant difference post-hoc tests. P < 0.05 was considered as significant. After 4 days the colonies were counted. RESULTS: Viability of P. gingivalis was reduced 10% and 20% subsequent to exposure to visible light and diode laser, respectively. The values were 65% and 75% for F. nucleatum in a period of 5-min, respectively. Exposure to visible light or laser beam in conjugation with the photosensitizers suspension caused significant reduction in the number of P. gingivalis in duration of 5-min, suggesting a synergic phototoxic effect. However, the survival rate of F. nucleatum following the exposure to laser with hydrogen peroxide, erythrosine and rhizome of Curcuma longa (curcumin) after 5-min was 10%, 20% and 90% respectively. CONCLUSION: Within the limitations of this study, the synergic phototoxic effect of visible light in combination with each of the photosensitizers on P. gingivalis and F. nucleatum. However, the synergic phototoxic effect of laser exposure and hydrogen peroxide and curcumin as photosensitizers on F. nucleatum was not shown.
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BACKGROUND: Patients undergoing orthodontic treatment experience varying degrees of pain with separator insertion. A survey of patients' attitude towards orthodontic treatment revealed that pain was the most discouraging factor related to their treatment. Moreover, it was the highest ranking reason for wanting to discontinue care. The purpose of this study was to determine the effect of low-level laser irradiation on dental pain induced by forces from separators in orthodontic treatment. MATERIALS AND METHODS: This study was an experimental clinical trial. Twenty-nine patients were recruited for this research. Low-level laser irradiation was applied on one half of the maxillary and mandibular arches for 5 days. The opposite half of the arches was considered the control group. Laser irradiation was applied for 30 seconds in the alveolar bone between the second premolars, first molars, and second molars. Pain perception was evaluated with a standardized questionnaire that was answered by patients before and after laser irradiation. Data was analyzed by Wilcoxon and Friedman test. P value ≤0.05 was considered significant. RESULTS: The highest pain level was reported at day 1 following separator placement and decreased gradually until day 5. At day 4 and 5, the pain intensity was lower in the laser group than in the control group; however, this finding was not statistically significant. At day 1 and 3, the pain intensity was higher in the laser group than in the control group; however, it was not statistically significant. At day 2, the pain intensity was lower in the laser group than in the control group and was statistically significant. CONCLUSION: Our findings suggest that there is no statistically significant difference in pain by using low-level laser irradiation.