750 research outputs found
Tularemia and Plague Survey in Rodents in Earthquake Zones in Southeastern Iran
OBJECTIVES: Earthquakes are one the most common natural disasters that lead to increased mortality and morbidity from transmissible diseases, partially because the rodents displaced by an earthquake can lead to an increased rate of disease transmission. The aim of this study was to evaluate the prevalence of plague and tularemia in rodents in the earthquake zones in southeastern Iran. METHODS: In April 2013, a research team was dispatched to explore the possible presence of diseases in rodents displaced by a recent earthquake magnitude 7.7 around the cities of Khash and Saravan in Sistan and Baluchestan Province. Rodents were trapped near and in the earthquake zone, in a location where an outbreak of tularemia was reported in 2007. Rodent serums were tested for a serological survey using an enzyme-linked immunosorbent assay. RESULTS: In the 13 areas that were studied, nine rodents were caught over a total of 200 trap-days. Forty-eight fleas and 10 ticks were obtained from the rodents. The ticks were from the Hyalomma genus and the fleas were from the Xenopsylla genus. All the trapped rodents were Tatera indica. Serological results were negative for plague, but the serum agglutination test was positive for tularemia in one of the rodents. Tatera indica has never been previously documented to be involved in the transmission of tularemia. CONCLUSIONS: No evidence of the plague cycle was found in the rodents of the area, but evidence was found of tularemia infection in rodents, as demonstrated by a positive serological test for tularemia in one rodent
Clade identification of symbiotic zooxanthellae of dominant sclerectinian coral species of intertidal pools in Hengam Island
Zooxanthellae of reef-building corals are unicellular dinoflagellates of the Symbiodinium genus, which has an important role in bleaching phenomenon. Symbiodinium and their coral hosts are sensitive to environmental stresses that include salinity, high temperatures, low temperatures, extreme light levels and turbidity. Tidal pools have harsh conditions due to lack of nutrients, food and pronounced changes in physical conditions such as pH, salinity and temperature, hence the study of symbiotic zooxanthellae on coral reefs of tidal pool seems to be necessary. Samples of five coral species that include Siderastrea savignyana, Coscinaraea columna, Anomastrea irregulariis, Cyphastrea serailia, Psammocora superficialis were collected at intertidal pool of Hengam Island in the northern Persian Gulf. Partial 28S nuclear ribosomal (nr) DNA of Symbiodinium were amplified by polymerase chain reaction (PCR) and then PCR products were analyzed by the phylogenetic analyses of the LSU DNA sequences based on PAUP and Clustal X software. The results showed that there are at least two clades of Symbiodinium from Hengam Island. Clade D was detected from 3 of the coral species whileclade C was found in 2 species only. This study showed dominance of clade D at intertidal pool in Hengam Island and the dominace of clade D might be explained by the high environmental stresses for the Persian Gulf.Key words: Persian Gulf, clade D, tides, Symbiodinium and Hengam Island
Cloning and expression of codon-optimized recombinant darbepoetin alfa in Leishmania tarentolae T7-TR
Darbepoetin alfa is an engineered and hyperglycosylated analog of recombinant human erythropoietin (EPO) which is used as a drug in treating anemia in patients with chronic kidney failure and cancer. This study desribes the secretory expression of a codon-optimized recombinant form of darbepoetin alfa in Leishmania tarentolae T7-TR. Synthetic codon-optimized gene was amplified by PCR and cloned into the pLEXSY-I-blecherry3 vector. The resultant expression vector, pLEXSYDarbo, was purified, digested, and electroporated into the L. tarentolae. Expression of recombinant darbepoetin alfa was evaluated by ELISA, reverse-transcription PCR (RT-PCR), Western blotting, and biological activity. After codon optimization, codon adaptation index (CAI) of the gene raised from 0.50 to 0.99 and its GC content changed from 56 to 58. Expression analysis confirmed the presence of a protein band at 40 kDa. Furthermore, reticulocyte experiment results revealed that the activity of expressed darbepoetin alfa was similar to that of its equivalent expressed in Chinese hamster ovary (CHO) cells. These data suggested that the codon optimization and expression in L. tarentolae host provided an efficient approach for high level expression of darbepoetin alfa. © 2015 Elsevier Ltd. All rights reserved
Impact of Health Literacy, Self-efficacy, and Outcome Expectations on Adherence to Self-care Behaviors in Iranians with Type 2 Diabetes.
OBJECTIVES:
Diabetic patients with higher health literacy (HL) may feel more confident in their ability to perform self-care behaviors and may have strong beliefs that diabetes-related behaviors will lead to specific outcomes. Our study aimed to document the relationships between HL, self-efficacy, outcome expectations, and diabetes self-care of patients with type 2 diabetes mellitus (T2DM) in Iran.
METHODS:
We conducted a cross-sectional observational study of 187 patients with T2DM. Participants completed the Functional Communicative and Critical Health Literacy scale, the Summary of Diabetes Self-Care Activities, the Diabetes Management Self-Efficacy Scale, Outcome Expectations Questionnaire, and a demographic questionnaire.
RESULTS:
Participants who received diabetes education (t = 5.79, p<0.001) and were married (F = 3.04, p<0.050) had better diabetes self-care behavior. There was a significant positive correlation between self-care behaviors and communicative HL (r = 0.455, p<0.010), critical HL (r = 0.297, p<0.010), self-efficacy (r = 0.512, p<0.010) and outcome expectations (r = 0.387, p<0.010). Diabetes education and marital status accounted for 16.9% of the variance in diabetes self-care. Self-efficacy, outcome expectations, communicative, and critical HL explained 28.0%, 1.5%, 3.7%, and 1.4% of the variance, respectively.
CONCLUSIONS:
This study revealed that the potential impact of self-efficacy, outcome expectations, communicative, and critical HL should be considered in the education program for patients with diabetes. We found self-efficacy to be the most important predictor of diabetes self-care. Therefore, the use of self-efficacy theory when designing patient education interventions could enhance diabetes self-care. It is essential that health care providers assess patient's HL levels to tailor health-related information specific to a domain of HL. This would fully inform patients and promote empowerment rather than simple compliance
Entropic forces drive self-organization and membrane fusion by SNARE proteins
SNARE proteins are the core of the cell’s fusion machinery and
mediate virtually all known intracellular membrane fusion reactions
on which exocytosis and trafficking depend. Fusion is catalyzed when
vesicle-associated v-SNAREs form trans-SNARE complexes (“SNAREpins”)
with target membrane-associated t-SNAREs, a zippering-like
process releasing ∼65 kT per SNAREpin. Fusion requires several SNAREpins,
but how they cooperate is unknown and reports of the number
required vary widely. To capture the collective behavior on the long
timescales of fusion, we developed a highly coarse-grained model that
retains key biophysical SNARE properties such as the zippering energy
landscape and the surface charge distribution. In simulations the
∼65-kT zippering energy was almost entirely dissipated, with fully
assembled SNARE motifs but uncomplexed linker domains. The
SNAREpins self-organized into a circular cluster at the fusion site,
driven by entropic forces that originate in steric–electrostatic interactions
among SNAREpins and membranes. Cooperative entropic
forces expanded the cluster and pulled the membranes together
at the center point with high force. We find that there is no critical
number of SNAREs required for fusion, but instead the fusion rate
increases rapidly with the number of SNAREpins due to increasing
entropic forces. We hypothesize that this principle finds physiological
use to boost fusion rates to meet the demanding timescales of
neurotransmission, exploiting the large number of v-SNAREs available
in synaptic vesicles. Once in an unfettered cluster, we estimate
≥15 SNAREpins are required for fusion within the ∼1-ms
timescale of neurotransmitter release
In vitro antifungal activity of various persian cultivars of Punica granatum L. Extracts against Candida species
Background: Resistance of Candida species to antifungal agents has potentially serious implications for management of infections. Candida species are now the fourth most common organisms isolated from hospitalized patients. Prevention and control of these infections will require new antimicrobial agents. Plant-derived antifungal agents have always been a source of novel therapeutics. Objectives: The aim of this study was to investigate the antifungal effect of pomegranate peel and pulp extracts against Candida species. Materials and Methods: Pomegranate pulp and peel were dried and powdered separately. The dried powders were extracted using a soxhlet extractor. The antifungal effect of pomegranate peel and pulp extracts were determined in vitro by using the minimum inhibitory concentration (MIC) against five standard species, including Candida albicans (ATCC 10231), Candida parapsilosis (ATCC 22019), Candida tropicalis (ATCC 750), Candida glabrata (PTCC 5297) and Candida krusei (PTCC 5295). Results: Maximum inhibitions were attributed to peel extract of the pomegranate cultivar against Candida species. The greatest antifungal inhibition among the eight different cultivars was observed for sour malas, sour white peel and sour summer extracts respectively, against the five Candida strains. The antifungal activity of pulp extracts against Candida species was somewhat negative. Conclusions: Our work suggested that pomegranate (Punica granatum L.) peel has potential antifungal activity against Candidiasis, and it is an attractive option for the development of new management strategies for candidiasis. � 2015, School of Pharmacy, Ahvaz Jundishapur University of Medical Sciences
Comparison of the tuberculin skin test and the QuantiFERON-TB Gold test in detecting latent tuberculosis in health care workers in Iran
OBJECTIVES: The tuberculin skin test (TST) and the QuantiFERON-TB Gold test (QFT) are used to identify latent tuberculosis infections (LTBIs). The aim of this study was to determine the agreement between these two tests among health care workers in Iran. METHODS: This cross-sectional study included 177 tuberculosis (TB) laboratory staff and 67 non-TB staff. TST indurations of 10 mm or more were considered positive. The Student's t-test and the chi-square test were used to compare the mean score and proportion of variables between the TB laboratory staff and the non-TB laboratory staff. Kappa statistics were used to evaluate the agreement between these tests, and logistic regression was used to assess the risk factors associated with positive results for each test. RESULTS: The prevalence of LTBIs according to both the QFT and the TST was 17 (95 confidence interval CI, 12% to 21%) and 16% (95% CI, 11% to 21%), respectively. The agreement between the QFT and the TST was 77.46%, with a kappa of 0.19 (95% CI, 0.04 to 0.34). CONCLUSIONS: Although the prevalence of LTBI based on the QFT and the TST was not significantly different, the kappa statistic was low between these two tests for the detection of LTBIs
A method to extract slip system dependent information for crystal plasticity models
A tool to implement a length scale dependency to classical crystal plasticity simulations is presented. Classical crystal plasticity models do not include a size effect; therefore, the size of the grain does not influence the simulated deformation. Classical crystal plasticity advancements have been through the inclusion of stress or strain gradient based constitutive models to improve the simulation of length scale dependent deformation. However, this tool presents an alternative to implementing a length scale, where the influence of slip pile-up in the form of dislocations at grain boundaries as a potential to explaining the Hall-Petch effect in materials. This is achieved by calculating the slip distance in adjacent grains for each slip system, by assuming the total slip length spans the grain in the slip direction. These calculations can occur in two ways. The first is the analysis occurs at the start of the simulation, therefore, only occurs once. If this approach is used, the computational cost of this tool is minute. However, if the simulations consider large deformations, during which it is expected that the grains are going to undergo large rotations, then it would be advantageous to the have the tool recalculate the information during the analysis. Consequently, the computational cost would depend on the resolution of the modelled geometry, the number of grains, and the number of slip systems. The tool also provides a capability to develop constitutive models based on complex grain boundary features which can be implemented in classical crystal plasticity models and gradient based crystal plasticity models. The described calculation process is implemented through a Fortran subroutine, which has been designed to be easily used in crystal plasticity simulations. The presented tool also includes Python code designed to link with microstructures built using DREAM.3D to extract the required input data to the Fortran subroutine. The proposed tool is not limited to classical crystal plasticity formulations, instead the data extracted and outputted from the Fortran subroutine can be used to serve alternative purposes in both stress and strain gradient crystal plasticity models. The proposed tool can be modified to extract additional data to that presented. The slip distance in the adjacent grain, the distance from the grain boundary of the current calculation point, and the interaction between slip systems between grains can be used in any crystal plasticity constitutive models
Effect of vitamins A, E, C and omega-3 fatty acids supplementation on the level of catalase and superoxide dismutase activities in streptozotocin-induced diabetic rats
Background: Since free radicals and antioxidant enzymes may play an important role in the development of diabetes, the present study was designed to assess the effect of supplementation with vitamins A, E and C and �-3 fatty acids on catalase and superoxide dismutase activity in streptozotocin (STZ)-induced diabetic rats. Methods: A total of 64 male Wistar rats weighing 250 g were divided into four groups as normal control, diabetic control, diabetic supplemented with vitamin A, E and C and diabetic supplemented with �-3 fatty acids. After four weeks the rats were anesthetized and catalase (CAT) and superoxide dismutase (SOD) activities were investigated in blood samples, liver and heart homogenates. Results: In diabetic rats, the activity levels of heart SOD (p < 0.001) and heart and liver CAT (p < 0.001) were significantly lower than in normal control rats. Supplementation with vitamins A, E and C significantly increased heart CAT (p = 0.05). No significant change was observed in diabetic rats supplemented with �-3 fatty acids. Conclusion: Supplementation with vitamins A, E and C and �-3 fatty acids was found to increase heart CAT activity in diabetic rats and they can be valuable candidates in the treatment of the complications of diabetes
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