118 research outputs found
Searching the genome of beluga (Huso huso) for sex markers based on targeted bulked segregant analysis (BSA)
In sturgeon aquaculture, where the main purpose is caviar production, a reliable method is needed to separate fish according to gender. Currently, due to the lack of external sexual dimorphism, the fish are sexed by an invasive surgical examination of the gonads. Development of a non-invasive procedure for sexing fish based on genetic markers is of special interest. In the present study we employed Bulked Segregant Analysis (BSA) methodology to search for DNA markers associated with the sex of the beluga sturgeon (Huso huso). DNA bulks (male and female) were created by combining equal amounts of genomic DNA from 10 fish of both sexes. A total of 101 decamer primers associated with the sex-specific sequences in non-sturgeon species was used for targeted screening of the bulks, resulting in 2846 bands that all of them were present in both sexes. Our results showed that sex chromosomes are weakly differentiated in the sturgeon genome and comprised sequences not complementary to the sex-specific primers in non-sturgeon species
Application of AFLP molecular marker for genetic analysis of black pomfret Parastromateus niger from the Persian Gulf
Black pomfret Parastromateus niger is a commercially important fishery resource in the Persian Gulf but harvesting its stocks lacks genetic identification of populations. AFLP technique was applied to analyze genetic diversity and population structure of 32 fish from coastal waters of Bandar Abbas, Bushehr and Abadan with 7 EcoRI/MseI primer pair combinations. In total, 381 bands were produced of which, 46 were polymorphic (12.07%). Percentage of polymorphic bands was higher in Bushehr samples (91.30%) than in Abadan (84.78%) and Bandar Abbas (73.91%) samples. The highest level of heterozygosity based on Nei’s coefficient and Shannon’s index was observed in Bushehr fish (0.38±0.16 and 0.54±0.21). Observed and effective alleles ranged from 1.73±0.44 and 1.53±0.40 in Bandar Abbas samples to 1.91±0.28 and 1.70±0.34 in Bushehr samples. The average Fst was 0.19 indicating high genetic differentiation among the three locations. Gene flow with mean of 1.93 was the lowest level between Bandar Abbas and Abadan (1.24). Nei's genetic identity revealed the least genetic similarity between the samples of Bandar Abbas and Abadan (0.77). AMOVA analysis demonstrated 81% of the genetic variation within populations and 19% among populations. The UPGMA dendrogram clustered all 32 individuals into 3 groups. In some cases individuals from the same region were grouped together but in most cases, gene exchange was observed to be common among the groups. Analyses provided evidence for genetic differentiation among the three locations, indicating separate populations of black pomfret in the northern Persian Gulf
Genetic analysis of sand whiting Sillago sihama from north Persian Gulf based on cytochrome oxidase C subunit I sequences
Silaginidae family fish from Perciforms, are appropriate candidates for shallow water and coastal aquaculture. At least three species of this family represents in the Persian Gulf. Genetic analysis of Sand whiting Sillago sihama , the most common species of family performed using COI gene. During the present study 10 samples were collected from Bushehr and Hormozgan provinces coastal waters. DNA extracted by modified CTAB method. Polymerase chain reactions were performed using universal primers - FISHF1 and FISHR1-. Sequencing results showed a 627 bp amplified fragment. Performing BLAST supported high identity to Sillago sihama species; hence morphometric identification confirms molecular barcoding. Genetic distance of 0.02 was calculated between samples of two areas based on Kimura 2- parameter using Mega software. Constructed phylogenetic tree using neighbor joining method whereas the Acanthopagrus latus sequences was used as an outgroup revealed no differentiation between two stations samples. In conclusion based on the results of the present study, the gene flow was high among studied samples and no significant differentiation was observed between Bushehr and Hormozgan samples. In conclusion no discrete populations differentiated based on the results of the present study
Oliveria decumbens and Pistacia atlantica Gum's Essential Oils: Assessment of Antimicrobial and Chemical Properties During Thermal Process
The essential oils usually have a good effect against undesirable microorganisms; therefore, they can be utilized as natural antimicrobial agents in food or their packaging. In this research, the antimicrobial attributes of two essential oils (Oliveria decumbens and Pistacia atlantica gum), have been investigated before and after thermal process (200°C - 10 minutes) against bacterial and mold spoilage in bread. Also, the compounds of essential oils were detected by gas chromatography-mass spectrometry. The main compounds of the essential oil of O. decumbens were carvacrol, thymol, and elemicin before and after thermal treatment. In the case of P. atlantica gum, only one prominent peak was observed in the chromatogram, which was related to the α-pinene. For both essential oils, the MIC and MFC against Aspergillus niger were 4000 and 8000 μL/ml, respectively. In comparison, the antimicrobial effect of both essential oils against Bacillus subtilis was higher than the mold. The amount of MIC and MBC were 125 and 250 μL/ml for Oliveria decumbens and 62.5 and 125 μL/ml for Pistacia atlantica gum, respectively. The results showed that these two essential oils have a promising effect against the main microorganisms of bread spoilage. The thermal process did not significantly affect the antimicrobial activity of Pistacia atlantica gum essential oil against A. niger but significantly decreased the antimicrobial activity against B. subtilis, while in the case of antimicrobial activity of Oliveria decumbens essential oil, the results were the opposite. Considering the fact that the most spoilage agents of the bread are molds so the use of Pistacia atlantica gum essential oil is recommended as natural preservatives in products that tolerate high heat treatment, such as bread and bakery products
Investigating effect of ghee on treating second-degree burn wound in rats
Background: High costs of treatment and rehabilitation lead to increased tendency of researchers in complementary therapies and using the compounds which have natural origin and are cheaper. Sheep ghee, known as yellow oil, is one of the compounds used in many parts of Iran for wound healing. Considering that few studies have been performed on the effect and rate of these materials on burn wound healing, the present work is aimed to investigate the effect of ghee on burn wound healing in rats. Methods: In this experimental study which was performed in the animal lab of the Hazrat Fatemeh Hospital in Tehran, 36 adult male Sprague-Dawley rats with the relative weight of 250-300 g were selected and second-degree burn with the area of 2�4 cm was induced in them. Then, they were randomly divided into 3 groups, 12 in each. To dress the burn point in 1 to 3 groups, silver sulfadiazine cream, ghee, and Vaseline were used, respectively. The evaluation process was monitored by photography with 5 days intervals using an accurate ruler and ImageJ software, version 1.45 (National Institutes of Health, Bethesda, Maryland, USA). On the 17th and 30th days, Tissue biopsies was performed for the epithelialization rate, degree and arrangement of collagen, and chronic and acute inflammatory cells, the sample of burn wound was sent for pathological investigation. Results: Results showed that, wound area was significantly reduced in ghee, and Vaseline groups compared with silver sulfadiazine cream on days 5th, 15th, and 25th (P=0.001). however, the difference between ghee and Vaseline group was not significant. In the 17-day time period, results of collagen arrangement (P= 0.000) and epithelialization results (P= 0.04), acute inflammatory cells (P= 0.001), and fibroplasias (P= 0.000) in 30th day were significantly better in ghee, and Vaseline groups. Conclusion: This study showed that, in contrast to the public belief in some regions in Iran, ghee could not accelerate healing of burn wound and promote histopathological indices. Therefore, they are not recommended. © 2017, Tehran University of Medical Sciences. All rights reserved
Investigating effect of ghee on treating second-degree burn wound in rats
Background: High costs of treatment and rehabilitation lead to increased tendency of researchers in complementary therapies and using the compounds which have natural origin and are cheaper. Sheep ghee, known as yellow oil, is one of the compounds used in many parts of Iran for wound healing. Considering that few studies have been performed on the effect and rate of these materials on burn wound healing, the present work is aimed to investigate the effect of ghee on burn wound healing in rats. Methods: In this experimental study which was performed in the animal lab of the Hazrat Fatemeh Hospital in Tehran, 36 adult male Sprague-Dawley rats with the relative weight of 250-300 g were selected and second-degree burn with the area of 2�4 cm was induced in them. Then, they were randomly divided into 3 groups, 12 in each. To dress the burn point in 1 to 3 groups, silver sulfadiazine cream, ghee, and Vaseline were used, respectively. The evaluation process was monitored by photography with 5 days intervals using an accurate ruler and ImageJ software, version 1.45 (National Institutes of Health, Bethesda, Maryland, USA). On the 17th and 30th days, Tissue biopsies was performed for the epithelialization rate, degree and arrangement of collagen, and chronic and acute inflammatory cells, the sample of burn wound was sent for pathological investigation. Results: Results showed that, wound area was significantly reduced in ghee, and Vaseline groups compared with silver sulfadiazine cream on days 5th, 15th, and 25th (P=0.001). however, the difference between ghee and Vaseline group was not significant. In the 17-day time period, results of collagen arrangement (P= 0.000) and epithelialization results (P= 0.04), acute inflammatory cells (P= 0.001), and fibroplasias (P= 0.000) in 30th day were significantly better in ghee, and Vaseline groups. Conclusion: This study showed that, in contrast to the public belief in some regions in Iran, ghee could not accelerate healing of burn wound and promote histopathological indices. Therefore, they are not recommended. © 2017, Tehran University of Medical Sciences. All rights reserved
Feasibility of mass cultivation on Nannochloropsis oculata microalgae in tubular culture system
The presnt study has been carried out to evaluate the Nannochloropsis oculata culture performance in 100L columnar plastic bags under two chemical media (TMRL and CONWAY) and 3 light regimes in the controlled conditions. Algae used for the experiment has been provided through culture of primitive stock and by transferring it to 2 L glassy erlenmeyer and 15 L plastic containers (as intermediate stage) using CONWAY media respectively. Daily evaluation of algae concentration was carried out during the 18 days culture period. At the end of the study produced algae has been sedimented to be used for evaluation of the dried matter and algae biomass. Results of the study showed that the concentration of the algae culture was 22±3.34×106 cells. ml^-1, at 8th day, and reached the concentration of 26.58±4.02×106 cells. ml^-1 at the final day of the culture course. Although the results revealed the possibility of achievement of acceptable concentration for the N.oculta by the method adopted in the present study, but the achievement was not such favourable to be considered as an altenative for the common method. Nevertheless it could be considered as an alternative for the constrained situations. Moreover according to the results there was no significant algae concentration difference between light regimes (P>0.05). Similar results were observed for the interaction effect of chemical media and light regimes. Meanwhile the ratio of dried matter obtained from algae under the TMRL media was significantly (P0.05) affect the algae production. Finally it could be concluded that the N.oculata algae could be successfully cultured in plastic columnar bags under the controlled conditions but the method adopted in the present study could be applicable in the improper conditions
The effect of sub-epineural platelet-rich plasma (PRP) on regeneration of the sciatic nerve in a rat model
Background: Peripheral nerve injury is one of the most challenging of modern surgical problem. Recent advances in understanding the physiological and molecular pathways demonstrated the important role of growth factors in peripheral nerve regeneration. Platelet-rich plasma (PRP) is a biological product that has many growth factors. The aim of this study was to investigate the effect of PRP in the regeneration of sciatic nerve crush in the rat model. Methods: In this experimental study that established in the animal lab of the Hazrat Fatemeh Hospital in Tehran from September to October 2013, Twenty-four healthy male Sprague-Dawley rats (200-250 g) were randomly divided into two groups. In all rats the sciatic nerve was cut and then carefully repaired by the tension free method under a light microscope. In group 1, after the repair, 0.05 μL of PRP was injected below the epineurium to the proximal and distal parts of the repaired area. In group 2 the same amount of normal saline was injected to the proximal and distal of the repaired area. After six weeks footprint analysis, neurophysiologic and histopathology evaluations were performed. Results: Significant differences existed between the two groups footprint analysis (P= 0.001). Also the nerve conduction latency test was significantly shorter in PRP group. (1.0233 ms in PRP group and 1.7375 ms in control) (P< 0.001). The average amplitude in the first group and the second group was 7.6250 mv (control) 6.3667 mv that does not show a statistically significant difference (P= 0.093). Significant differences between the two groups in the number of axons of the proximal portion of the study was not seen (P= 0.29). The parameters included number of axons of the proximal and the distal part of axons, the diameter of the distal and proximal axons in the two groups were compared. In the two groups there was statistically significant difference between the above parameters. (P= 0.298). Conclusion: It seems that PRP may have an important role in peripheral nerve regeneration and functional recovery after nerve laceration and repair. Further clinical evaluation recommended. © 2016, Tehran University of Medical Sciences. All rights reserved
Phase fluctuations, dissipation and superfluid stiffness in d-wave superconductors
We study the effect of dissipation on quantum phase fluctuations in d-wave
superconductors. Dissipation, arising from a nonzero low frequency optical
conductivity which has been measured in experiments below , has two
effects: (1) a reduction of zero point phase fluctuations, and (2) a reduction
of the temperature at which one crosses over to classical thermal fluctuations.
For parameter values relevant to the cuprates, we show that the crossover
temperature is still too large for classical phase fluctuations to play a
significant role at low temperature. Quasiparticles are thus crucial in
determining the linear temperature dependence of the in-plane superfluid
stiffness. Thermal phase fluctuations become important at higher temperatures
and play a role near .Comment: Presentation improved, new references added (10 latex pages, 3 eps
figures). submitted to PR
Experimental implications of quantum phase fluctuations in layered superconductors
I study the effect of quantum and thermal phase fluctuations on the in-plane
and c-axis superfluid stiffness of layered d-wave superconductors. First, I
show that quantum phase fluctuations in the superconductor can be damped in the
presence of external screening of Coulomb interactions, and suggest an
experiment to test the importance of these fluctuations, by placing a metal in
close proximity to the superconductor to induce such screening. Second, I show
that a combination of quantum phase fluctuations and the linear temperature
dependence of the in-plane superfluid stiffness leads to a linear temperature
dependence of the c-axis penetration depth, below a temperature scale
determined by the magnitude of in-plane dissipation.Comment: 6 pgs, 1 figure, minor changes in comparison with c-axis expt, final
published versio
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