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11.
Immunogenicity and efficacy of a bivalent DNA vaccine containing LeIF and TSA genes against murine cutaneous leishmaniasis
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Nahid Maspi Fatemeh Ghaffarifar Zohreh Sharifi Abdolhossein Dalimi Mohammad Saaid Dayer 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2017,125(3):249-258
There is no effective vaccine for the prevention and elimination of leishmaniasis. For this reason, we assessed the protective effects of DNA vaccines containing LeIF, TSA genes alone, or LeIF–TSA fusion against cutaneous leishmaniasis pEGFP‐N1 plasmid (empty vector) and phosphate buffer saline (PBS) were used as control groups. Therefore, cellular and humoral immune responses were evaluated before and after the challenge with Leishmania major. Lesion diameter was also measured 3–12 weeks after challenge. All immunized mice with plasmid DNA encoding Leishmania antigens induced the partial immunity characterized by increased IFN‐γ and IgG2a levels compared with control groups (p < 0.001). Furthermore, the immunized mice showed significant reduction in mean lesion sizes compared with mice in empty vector and PBS groups (p < 0.05). The reduction in lesion diameter was 29.3%, 34.1%, and 46.2% less in groups vaccinated with LeIF, TSA, and LeIF‐TSA, respectively, than in PBS group at 12th week post infection. IFN/IL‐4 and IgG2a/IgG1 ratios indicated that group receiving LeIF–TSA fusion had the highest IFN‐γ and IgG2a levels. In this study, DNA immunization promoted Th1 immune response characterized by higher IFN‐γ and IgG2a levels and also reduction in lesion size. These results showed that a bivalent vaccine containing two distinct antigens may induce more potent immune responses against leishmaniasis. 相似文献
12.
Plasmonic metamaterials are artificial materials typically composed of noble metals in which the features of photonics and electronics are linked by coupling photons to conduction electrons of metal (known as surface _lasmon). These rationally designed structures have spurred interest noticeably since they demonstrate some fascinating properties which are unattainable with naturally occurring materials. Complete absorption of light is one of the recent exotic properties of plasmonic metamaterials which has broadened its application area considerably. This is realized by designing a medium whose impedance matches that of free space while being opaque. If such a medium is filled with some lossy medium, the resulting structure can absorb light totally in a sharp or broad frequency range. Although several types of metamaterials perfect absorber have been demonstrated so far, in the current paper we overview (and focus on) perfect absorbers based on nanocomposites where the total thickness is a few tens of nanometer and the absorption band is broad, tunable and insensitive to the angle of incidence. The nanocomposites consist of metal nanoparticles embedded in a dielectric matrix with a high filling factor close to the percolation threshold. The filling factor can be tailored by the vapor phase co-deposition of the metallic and dielectric components. In addition, novel wet chemical approaches are discussed which are bio-inspired or involve synthesis within levitating Leidenfrost drops, for instance. Moreover, theoretical considerations, optical properties, and potential application of perfect absorbers will be presented. 相似文献
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Behrang Keshavarz Lawrence J. Hettinger Daniel Vena Jennifer L. Campos 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2014,232(3):827-836
Vection is the illusion of self-motion in the absence of real physical movement. The aim of the present study was to analyze how multisensory inputs (visual and auditory) contribute to the perception of vection. Participants were seated in a stationary position in front of a large, curved projection display and were exposed to a virtual scene that constantly rotated around the yaw-axis, simulating a 360° rotation. The virtual scene contained either only visual, only auditory, or a combination of visual and auditory cues. Additionally, simulated rotation speed (90°/s vs. 60°/s) and the number of sound sources (1 vs. 3) were varied for all three stimulus conditions. All participants were exposed to every condition in a randomized order. Data specific to vection latency, vection strength, the severity of motion sickness (MS), and postural steadiness were collected. Results revealed reduced vection onset latencies and increased vection strength when auditory cues were added to the visual stimuli, whereas MS and postural steadiness were not affected by the presence of auditory cues. Half of the participants reported experiencing auditorily induced vection, although the sensation was rather weak and less robust than visually induced vection. Results demonstrate that the combination of visual and auditory cues can enhance the sensation of vection. 相似文献
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Zahra FARSI Nahid DEHGHAN-NAYERI Reza NEGARANDEH Soheila BROOMAND 《Japan Journal of Nursing Science》2010,7(1):9-18
Aim: Iran's health-care system has witnessed profound changes in the last decades. Despite its progress, the system has currently faced many challenges in one of the important subsystems, nursing. The present review article aimed to present an overview of the opportunities and challenges of the Iranian nursing system, based on recent literature.
Methods: A broad search of the English and Persian-language literature was carried out, incorporating both electronic and manual components from 1999 to 2009. The results of the investigations among the searched literature are summarized.
Results: The major challenges are nursing shortages, job dissatisfaction, poor social position of nurses, the gap between theory and practice, lack of community-based nursing care, lack of an appropriate student recruiting system, and shortages in the nursing educational curriculums.
Conclusion: The authors believe that media, political and public support play a pivotal role in improving the image of nursing in society, increasing motivation among Iranian nurses, and promoting the sociocultural climate and the welfare of nurses, which will result in higher levels of quality of care as well as greater patient satisfaction. 相似文献
Methods: A broad search of the English and Persian-language literature was carried out, incorporating both electronic and manual components from 1999 to 2009. The results of the investigations among the searched literature are summarized.
Results: The major challenges are nursing shortages, job dissatisfaction, poor social position of nurses, the gap between theory and practice, lack of community-based nursing care, lack of an appropriate student recruiting system, and shortages in the nursing educational curriculums.
Conclusion: The authors believe that media, political and public support play a pivotal role in improving the image of nursing in society, increasing motivation among Iranian nurses, and promoting the sociocultural climate and the welfare of nurses, which will result in higher levels of quality of care as well as greater patient satisfaction. 相似文献
17.
Karolina Sikorska Nahid Mostafavi Montazeri André Uitterlinden Fernando Rivadeneira Paul HC Eilers Emmanuel Lesaffre 《European journal of human genetics : EJHG》2015,23(10):1384-1391
Analysis of genome-wide association studies with longitudinal data using standard procedures, such as linear mixed model (LMM) fitting, leads to discouragingly long computation times. There is a need to speed up the computations significantly. In our previous work (Sikorska et al: Fast linear mixed model computations for genome-wide association studies with longitudinal data. Stat Med 2012; 32.1: 165–180), we proposed the conditional two-step (CTS) approach as a fast method providing an approximation to the P-value for the longitudinal single-nucleotide polymorphism (SNP) effect. In the first step a reduced conditional LMM is fit, omitting all the SNP terms. In the second step, the estimated random slopes are regressed on SNPs. The CTS has been applied to the bone mineral density data from the Rotterdam Study and proved to work very well even in unbalanced situations. In another article (Sikorska et al: GWAS on your notebook: fast semi-parallel linear and logistic regression for genome-wide association studies. BMC Bioinformatics 2013; 14: 166), we suggested semi-parallel computations, greatly speeding up fitting many linear regressions. Combining CTS with fast linear regression reduces the computation time from several weeks to a few minutes on a single computer. Here, we explore further the properties of the CTS both analytically and by simulations. We investigate the performance of our proposal in comparison with a related but different approach, the two-step procedure. It is analytically shown that for the balanced case, under mild assumptions, the P-value provided by the CTS is the same as from the LMM. For unbalanced data and in realistic situations, simulations show that the CTS method does not inflate the type I error rate and implies only a minimal loss of power. 相似文献
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Nahid Rahmani Ali Kiani Mohammad Ali Mohseni-Bandpei Iraj Abdollahi 《Journal of bodywork and movement therapies》2018,22(1):147-151
Objective
The purposes of this study were; a) to compare multifidus muscle cross sectional area (CSA) in male adolescents suffering from low back pain (LBP) with healthy male adolescents using ultrasonography (US), and b) to assess the correlation between multifidus muscle size and demographic variables.Methods
A random sample of 40 healthy boys (as a control group) and 40 boys with LBP (as an experimental group) at the age range of 15–18 years was recruited in the present cohort study. Multifidus muscle dimensions including CSA, antero-posterior and medio-lateral dimensions were measured at level of L5 in both groups using US.Results
The results of an independent t-test to compare multifidus muscle size between the experimental and control groups showed a significant difference between the two groups in terms of CSA, antro-posterior and medio-lateral dimensions so that the experimental group had smaller muscle size than the control group. A significant correlation was found between height, weight and body mass index (BMI) and multifidus muscle size, but no significant correlation was observed between age and muscle size. Pain intensity and functional disability index was significantly correlated with muscle size in the experimental group.Conclusions
According to the results, multifidus muscle size was decreased in 15–18 years old male adolescents suffering from LBP compared with their healthy counterparts. Further studies are needed to support the findings of the present study. 相似文献20.
Reza Heidari Akram Jamshidzadeh Nahid Keshavarz Negar Azarpira 《Scientia pharmaceutica》2015,83(1):143-158
Methimazole is the most widely prescribed antithyroid medication in humans. However, hepatotoxicity is a deleterious adverse effect associated with methimazole administration. No specific protective agent has been developed against this complication yet. This study was designed to investigate the role of taurine as a hepatoprotective agent against methimazole-induced liver injury in mice. Different reactive metabolites were proposed to be responsible for methimazole hepatotoxicity. Hence, methimazole-induced liver injury was investigated in intact and/or enzyme-induced animals in the current investigation. Animals were treated with methimazole (200 mg/kg, by gavage), and hepatic injury induced by this drug was investigated in intact and/or enzyme-induced groups. Markers such as lipid peroxidation, hepatic glutathione content, alanine aminotransferase (ALT) and alkaline phosphatase (ALP) in plasma, and histopathological changes in the liver of animals were monitored after drug administration. Methimazole caused liver injury as revealed by increased plasma ALT. Furthermore, a significant amount of lipid peroxidation was detected in the drug-treated animals, and hepatic glutathione reservoirs were depleted. Methimazole-induced hepatotoxicity was more severe in enzyme-induced mice. The above-mentioned alterations in hepatotoxicity markers were endorsed by significant histopathological changes in the liver. Taurine administration (1 g/kg, i.p.) effectively alleviated methimazole-induced liver injury in both intact and/or enzyme-induced animals. 相似文献