129 research outputs found
The Role of Herpes Simplex Virus Type 1 Glycoprotein K in Neuroinvasion and Immunopathogenesis of Herpes Keratitis
ABSTRACT Herpes simplex virus type 1 is a common neurotropic pathogen responsible for a multitude of human diseases ranging from mucocutaneous lesions, keratitis to life-threatening encephalitis. The hallmark of the HSV-1 life cycle is infection of sensory neurons, where the virus establishes a latent infection for the life of the host. Viral envelope glycoproteins play important roles in viral life cycle and virus-host interaction. Viral glycoproteins gK, gM, gE and the membrane protein UL11 have been shown to be important for virus assembly, egress and virus spread. To investigate the relative importance of each of gK, gM, gE and UL11 in infection of ganglionic neurons following ocular inoculation, recombinant viruses were constructed, characterized and used to infect mice via the ocular route. Results showed that gK plays the most important role in infection of ganglionic neurons following ocular inoculation in the mouse model. gK null viruses exhibited major defects in replication and cell to cell spread in tissue culture. To further investigate the role of gK in the pathogenesis of herpes keratitis and to delineate gK domains responsible for replication and neuroinvasion, recombinant viruses lacking the amino-terminus of gK were constructed. Characterization of the constructed viruses revealed that the amino terminus of gK is dispensable for replication in tissue culture; however, it is required for neuroinvasion and cell to cell spread. Moreover, the virus lacking the amino terminus in gK was unable to infect corneal epithelium and establish latency in the trigeminal ganglia after ocular inoculation of mice. In the above mentioned investigation, we have observed that lack of the amino terminus of gK is associated with lack of ocular disease in infected mice. Further investigation of this observation (still in progress) revealed a potential role for gK in the immunopathogenesis of keratitis. The research work presented in this dissertation is of paramount importance as it identifies gK as an important neurotropic determinant, and it delineates gK domains responsible for neuroinvasion and immunopathogenesis in vivo. This work may lead to the development of replication competent, safe vaccine vectors, and paves the way for the discovery of new therapeutics for herpes keratitis
Effect of Harvest Time on Yield and Quality of Thymus vulgaris L. Essential Oil in Isfahan Province, Iran
Thyme (Thymus vulgaris L.) is a perennial sub shrub belonging to family Lamiaceae. Thyme essential oils have been used for many thousands of years, especially in food preservation, pharmaceuticals, alternative medicine and natural therapies. In order to determine the effect of harvest time on quality and quantity of essential oil in thyme, this experiment was done in a randomized complete block design with three replications at research station of Islamic Azad University, Khorasgan (Isfahan) during 2010-2011. Plants were harvested in five stages: before blooming, beginning of blooming, 50% blooming, full blooming and fruit set. The essential oils obtained from the phenological stages of thyme were analyzed by using GC/MS. The results obtained in our study showed that the phenological stages had very significant effects (P < 0.01) on essential oil yield and percentage as well as thymol percentage and yield. The highest essential oil content of thyme (2.42%) was extracted at the beginning of blooming stage. Analysis and identification of components showed that thymol is the main compound in all samples. The highest thymol content of thyme (74.8%) was extracted at the full blooming stage. According to the results of this research, harvesting the thyme at 50% blooming stage have maximum essential oil quality and quantity in Isfahan province
Effect of rigid vegetation on the velocity, turbulence, and wave structure in open channel flows
Vegetation plays an important role in changing the flow characteristics and flooding of natural channels. In this study a series of laboratory programmes were undertaken to investigate the effects of emergent and submerged vegetation on the flow structure in compound, simple and wide channels. The vegetation consisted of rigid rods replicating tree vegetation. In a laboratory flume, wooden rods were used to replicate this with three density states and one non-vegetated state being used to compare their effects on the flow characteristics in the flume. Velocities were measured using 3-D Acoustic Doppler Velocimeters (ADV), with one downward facing and one upward facing probe. The results showed that the velocities decreased within and near the vegetation zones, and the flow accelerated and transferred towards the upper part of the rods, or to the non-vegetated zone, along the flume. The vegetation density was shown to control the magnitude of these effects. Also, in the transition zones between the floodplain and the main channel in the compound channel, or in transition zones between the vegetated and non-vegetation zones, or near the top of the vegetation in the simple and wide channels, the velocity fluctuations and Reynolds stresses were observed to have relatively high values. The magnitude of the velocity fluctuations and the Reynolds stresses were shown to be highly depended upon the vegetation density. Vegetation reduces the energy and increases the flow depth, with a reduction in the velocities. It also protects the channel bed against erosion due to resistance of the flow and enhances settlement of sediment. Behind the rods the longitudinal velocity was observed to be very low, but other velocities (transverse and vertical) were high. Also velocity fluctuations and Reynolds stress components were higher behind the rods. However, as the distance from the rods increased, then the longitudinal velocity increased and the transverse and vertical velocities and Reynolds stresses all decreased. For many conditions in vegetated open channel flows, rods may produce transverse waves due to vortex shedding. Some experiments in the wide channel, of 1200 mm width, 10 m length, and 24 mm rods diameter were undertaken using different rod arrangements and densities to investigate the frequency and amplitude of these waves. From these experiments, and a subsequent analysis of the results, a new equation was developed for calculating the Strouhal number for water and two new equations were established for calculating the wave amplitude for different rod arrangements and densities. These equations were experimentally proved to better match the data variations than the conventional equation.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Effect of rigid vegetation on the velocity, turbulence, and wave structure in open channel flows
Vegetation plays an important role in changing the flow characteristics and flooding of natural channels. In this study a series of laboratory programmes were undertaken to investigate the effects of emergent and submerged vegetation on the flow structure in compound, simple and wide channels. The vegetation consisted of rigid rods replicating tree vegetation. In a laboratory flume, wooden rods were used to replicate this with three density states and one non-vegetated state being used to compare their effects on the flow characteristics in the flume. Velocities were measured using 3-D Acoustic Doppler Velocimeters (ADV), with one downward facing and one upward facing probe. The results showed that the velocities decreased within and near the vegetation zones, and the flow accelerated and transferred towards the upper part of the rods, or to the non-vegetated zone, along the flume. The vegetation density was shown to control the magnitude of these effects. Also, in the transition zones between the floodplain and the main channel in the compound channel, or in transition zones between the vegetated and non-vegetation zones, or near the top of the vegetation in the simple and wide channels, the velocity fluctuations and Reynolds stresses were observed to have relatively high values. The magnitude of the velocity fluctuations and the Reynolds stresses were shown to be highly depended upon the vegetation density. Vegetation reduces the energy and increases the flow depth, with a reduction in the velocities. It also protects the channel bed against erosion due to resistance of the flow and enhances settlement of sediment. Behind the rods the longitudinal velocity was observed to be very low, but other velocities (transverse and vertical) were high. Also velocity fluctuations and Reynolds stress components were higher behind the rods. However, as the distance from the rods increased, then the longitudinal velocity increased and the transverse and vertical velocities and Reynolds stresses all decreased. For many conditions in vegetated open channel flows, rods may produce transverse waves due to vortex shedding. Some experiments in the wide channel, of 1200 mm width, 10 m length, and 24 mm rods diameter were undertaken using different rod arrangements and densities to investigate the frequency and amplitude of these waves. From these experiments, and a subsequent analysis of the results, a new equation was developed for calculating the Strouhal number for water and two new equations were established for calculating the wave amplitude for different rod arrangements and densities. These equations were experimentally proved to better match the data variations than the conventional equation.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Land surface temperature assessment in semi-arid residential area of Tehran, Iran using Landsat imagery
Land cover change especially from green areas to urban areas may increase land surface temperature (LST). In this study, Landsat Enhanced Thematic Mapper Plus (ETM+) on 15 May 2000 (spring), 9 July 2000 (summer), 26 November 2000 (autumn) and 10 January 2001(winter) were utilized to study LST in Tehran, Iran. The accuracy of the LST analysis was evaluated using six year ground temperature data. The Non Linear Correlation Coefficient (NLCC) between normalized differences vegetation index (NDVI) and LST was found to be higher in the spring compared to the other seasons. The LST value in the west of the city was similar to the surrounding areas, but in north, east and south of the city were lower compared to the north, north east and east of the surrounding areas in all seasons. The gravel and sandy soil in the western part of the surrounding areas were warmer than the impervious surface area (ISA) in the city in summer. It was found that high urban density in semi arid climate with low vegetation in the surrounding areas does not increase the LST value in the city compared to its surrounding areas
Superficial cryotherapy versus intralesional corticosteroid injection in alopecia areata: A comparative clinical and dermoscopic study
Background: Alopecia areata (AA) is a common, non-scarring type of hair loss, affecting approximately 2.1% of the population. Many modalities of treatment are recommended like steroid injection, topical Immunotherapy, and several systemic therapies, but none of them can prevent or alter the course of the disease with variable degrees of improvement.Objective: To evaluate efficacy and safety of superficial cryotherapy versus intralesional corticosteroid injection in the treatment of alopecia areata. Patients and Methods: Thirty patients aged 14-58 years, with localized multiple patchy alopecia areata (at least two patches), were enrolled in this study. In each patient, one patch was treated by superficial cryotherapy via liquid nitrogen spray. This involved two treatment cycles/sessions, each lasting 3-5 seconds. The other patch was treated with intralesional steroid injection (triamcinolone acetonide 5 mg/ml, 0.1ml /cm2. Sessions were repeated every three weeks up to three months. The target lesions were evaluated clinically using SALT score and by 2 blinded dermatologists and dermoscopically at baseline, every session, and the end of the study (one month after the last session). Results: At the end of the study, the clinical response (number of the patients with hair growth > 20%) to superficial cryotherapy was about 83.3% (25 patients out of 30 patients). While in the steroid group the clinical response was about 80% (24 patients out of 30 patients). There was a statistically significant reduction in SALT score and dermoscopic parameters at the end of the study in both groups with no significant difference between them. There was a significant clinico-dermoscopic relation between hair regrowth and dermoscopic findings.Conclusion: Superficial cryotherapy is an effective and safe therapeutic modality for AA with advantages of simplicity and noninvasiveness
Effect of rigid vegetation on the velocity, turbulence, and wave structure in open channel flows
Vegetation plays an important role in changing the flow characteristics and flooding of natural channels. In this study a series of laboratory programmes were undertaken to investigate the effects of emergent and submerged vegetation on the flow structure in compound, simple and wide channels. The vegetation consisted of rigid rods replicating tree vegetation. In a laboratory flume, wooden rods were used to replicate this with three density states and one non-vegetated state being used to compare their effects on the flow characteristics in the flume. Velocities were measured using 3-D Acoustic Doppler Velocimeters (ADV), with one downward facing and one upward facing probe. The results showed that the velocities decreased within and near the vegetation zones, and the flow accelerated and transferred towards the upper part of the rods, or to the non-vegetated zone, along the flume. The vegetation density was shown to control the magnitude of these effects. Also, in the transition zones between the floodplain and the main channel in the compound channel, or in transition zones between the vegetated and non-vegetation zones, or near the top of the vegetation in the simple and wide channels, the velocity fluctuations and Reynolds stresses were observed to have relatively high values. The magnitude of the velocity fluctuations and the Reynolds stresses were shown to be highly depended upon the vegetation density. Vegetation reduces the energy and increases the flow depth, with a reduction in the velocities. It also protects the channel bed against erosion due to resistance of the flow and enhances settlement of sediment. Behind the rods the longitudinal velocity was observed to be very low, but other velocities (transverse and vertical) were high. Also velocity fluctuations and Reynolds stress components were higher behind the rods. However, as the distance from the rods increased, then the longitudinal velocity increased and the transverse and vertical velocities and Reynolds stresses all decreased. For many conditions in vegetated open channel flows, rods may produce transverse waves due to vortex shedding. Some experiments in the wide channel, of 1200 mm width, 10 m length, and 24 mm rods diameter were undertaken using different rod arrangements and densities to investigate the frequency and amplitude of these waves. From these experiments, and a subsequent analysis of the results, a new equation was developed for calculating the Strouhal number for water and two new equations were established for calculating the wave amplitude for different rod arrangements and densities. These equations were experimentally proved to better match the data variations than the conventional equation
Pneumatic versus hydrostatic reduction in the treatment of intussusception in children
Background: The aim of this study was to compare pneumatic reduction under guidance of fluoroscopy and hydrostatic saline enema reduction under guidance of ultrasound in treatment of intussusception in pediatric patients.Methods: The study included 80 patients with intussusception in the time period from September 2014 to September 2015 who were divided into two groups: group A included 40 patients who underwent US guided hydrostatic reduction and group B included 40 patients who underwent fluoroscopic guided pneumatic reduction.Results: The success rate was significantly higher in the pneumatic group (80%) (P = 0.017) when compared to the hydrostatic group (55%) after 1st trial. However, the outcome was equal in both groups after the 2nd trial with success rate of 82.5%. The time needed for reduction was significantly shorter in the pneumaic group (P =0.001). There was only one case of perforation in hydrostatic group (2.5%).Conclusion: Pneumatic reduction is safe, simple, fast, less messy and as effective as hydrostatic reduction.Keywords: hydrostatic reduction, intussusception, pneumatic reductio
The ASTER DEM generation for geomorphometric analysis of the Central Alborz mountains, Iran
This research focuses on the ASTER DEM generation for visual and mathematical analysis of topography, landscapes and landforms, as well as modeling of surface processes of Central Alborz, Iran. ASTER DEM 15 m generated using tie points over the Central Alborz and Damavand volcano with 5671 m height from ASTER (Advanced Space borne Thermal Emission and Reflection Radiometer) satellite data using PCI Geomatica 9.1. Geomorphic parameters are useful to identify and describe geomorphologic forms and processes, which were extracted from ASTER DEM in GIS environment such as elevation, aspect, slope angle, vertical curvature, and tangential curvature. Although the elevation values are slightly low in altitudes above 5500 m asl., the ASTER DEM is useful in interpretation of the macro- and meso-relief, and provides the opportunity for mapping especially at medium scales (1:100,000 and 1:50,000). ASTER DEM has potential to be a best tool to study 3D model for to geomorphologic mapping and processes of glacial and per glacial forms above 4300 m asl
Effect of Harvest Time on Yield and Quality of Thymus vulgaris L. Essential Oil in Isfahan Province, Iran
Thyme (Thymus vulgaris L.) is a perennial sub shrub belonging to family Lamiaceae. Thyme essential oils have been used for many thousands of years, especially in food preservation, pharmaceuticals, alternative medicine and natural therapies. In order to determine the effect of harvest time on quality and quantity of essential oil in thyme, this experiment was done in a randomized complete block design with three replications at research station of Islamic Azad University, Khorasgan (Isfahan) during 2010-2011. Plants were harvested in five stages: before blooming, beginning of blooming, 50% blooming, full blooming and fruit set. The essential oils obtained from the phenological stages of thyme were analyzed by using GC/MS. The results obtained in our study showed that the phenological stages had very significant effects (P < 0.01) on essential oil yield and percentage as well as thymol percentage and yield. The highest essential oil content of thyme (2.42%) was extracted at the beginning of blooming stage. Analysis and identification of components showed that thymol is the main compound in all samples. The highest thymol content of thyme (74.8%) was extracted at the full blooming stage. According to the results of this research, harvesting the thyme at 50% blooming stage have maximum essential oil quality and quantity in Isfahan province
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