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81.
Mahsa Keivan Bahari Gholamreza Rouhi Mohammad Reza Movahhedy 《Computer methods in biomechanics and biomedical engineering》2013,16(8):835-844
A computational framework was developed to simulate the bone remodelling process as a structural topology optimisation problem. The mathematical formulation of the Level Set technique was extended and then implemented into a coronal plane model of the proximal femur to simulate the remodelling of internal structure and external geometry of bone into the optimal state. Results indicated that the proposed approach could reasonably mimic the major geometrical and material features of the natural bone. Simulation of the internal bone remodelling on the typical gross shape of the proximal femur, resulted in a density distribution pattern with good consistency with that of the natural bone. When both external and internal bone remodelling were simulated simultaneously, the initial rectangular design domain with a regularly distributed mass reduced gradually to an optimal state with external shape and internal structure similar to those of the natural proximal femur. 相似文献
82.
Hamid Mahmoudzadeh-Niknam Ghader Khalili Firoozeh Abrishami Ali Najafy Vahid Khaze 《The Korean journal of parasitology》2013,51(1):69-74
Leishmania tropica is one of the causative agents of leishmaniasis in humans. Routes of infection have been reported to be an important variable for some species of Leishmania parasites. The role of this variable is not clear for L. tropica infection. The aim of this study was to explore the effects of route of L. tropica infection on the disease outcome and immunologic parameters in BALB/c mice. Two routes were used; subcutaneous in the footpad and intradermal in the ear. Mice were challenged by Leishmani major, after establishment of the L. tropica infection, to evaluate the level of protective immunity. Immune responses were assayed at week 1 and week 4 after challenge. The subcutaneous route in the footpad in comparison to the intradermal route in the ear induced significantly more protective immunity against L. major challenge, including higher delayed-type hypersensitivity responses, more rapid lesion resolution, lower parasite loads, and lower levels of IL-10. Our data showed that the route of infection in BALB/c model of L. tropica infection is an important variable and should be considered in developing an appropriate experimental model for L. tropica infections. 相似文献
83.
Rohollah Nikooie Sohil Jafari-Sardoie Vahid Sheibani Amir Nejadvaziri Chatroudi 《Journal of cellular physiology》2020,235(7-8):5649-5665
The TGF-β1-Smad pathway is a well-known negative regulator of muscle growth; however, its potential role in resistance training-induced muscle hypertrophy is not clear. The present study proposed to determine whether and how this pathway may be involved in resistance training-induced muscle hypertrophy. Skeletal muscle samples were collected from the control, trained (RT), control + SB431542 (CITGF), and trained + SB431542 (RTITGF) animals following 3, 5, and 8 weeks of resistance training. Inhibition of the TGF-β1-Smad pathway by SB431542 augmented muscle satellite cells activation, upregulated Akt/mTOR/S6K1 pathway, and attenuated FOXO1 and FOXO3a expression in the CITGF group (all p < .01), thereby causing significant muscle hypertrophy in animals from the CITGF. Resistance training significantly decreased muscle TGF-β1 expression and Smad3 (P-Smad3S423/425) phosphorylation at COOH-terminal residues, augmented Smad2 (P-Smad2-LS245/250/255) and Smad3 (P-Smad3-LSer208) phosphorylation levels at linker sites (all p < .01), and led to a muscle hypertrophy which was unaffected by SB431542, suggesting that the TGF-β1-Smad signaling pathway is involved in resistance training-induced muscle hypertrophy. The effects of inhibiting the TGF-β1-Smad signaling pathway were not additive to the resistance training effects on FOXO1 and FOXO3a expression, muscle satellite cells activation, and the Akt/mTOR/S6K1 pathway. Resistance training effect of satellite cell differentiation was independent of the TGF-β1-Smad signaling pathway. These results suggested that the effect of the TGF-β1-Smad signaling pathway on resistance training-induced muscle hypertrophy can be attributed mainly to its diminished inhibitory effects on satellite cell activation and protein synthesis. Suppressed P-Smad3S423/425 and enhanced P-Smad2-LS245/250/255 and P-Smad3-LSer208 are the molecular mechanisms that link the TGF-β1-Smad signaling pathway to resistance training-induced muscle hypertrophy. 相似文献
84.
Zahra Moallemzadegan Vahid Hosseininaveh 《Archives Of Phytopathology And Plant Protection》2013,46(16):1560-1571
Activity of α-amylase was revealed in the midgut and salivary glands of the wheat and barley pentatomid pest, A. acuminata. The activity was determined in salivary gland more than those in midgut. Optimal activity of the enzyme occurred at 40°C. Optimal pH activity in salivary gland (pH = 6) was more than those in the midgut (pH = 4.5). pH stability analysis of the enzyme showed that the enzyme is more stable at slightly acidic pHs than those at acidic and alkaline pHs. However, α-amylase is more stable at acidic pH in long period of time. Temperature stability analysis determined the enzyme was remarkably active over a broad range of temperature (5–40°C). α-Amylase activity was decreased after addition of MgCl2, Tris, Triton X-100, CuSO4, SDS, urea and CaCl2. The salts NaCl and KCl increased the enzyme activity from midgut and salivary glands. Zymogram analysis of midgut and salivary gland extract showed at least two bands of amylase activity in the midgut and salivary glands. 相似文献
85.
Fully matured DCs with large amount cytoplasm and copious dendritic projections were visible at the end of culturing period in the presence of MCM, TNF-α and poly (I:C), with or without FEECM. Thus, DCs generated with these maturation factors are nonadherent and have typical satellite morphology. Flow cytometric analysis using anti-CD14, -CD80, -CD86, -HLA-DR and -CD83 revealed that expression of CD14 is decreased in particular in FEECM treated DCs, on day 5 and expression of CD80, CD86 and HLA-DR was the higher when FEECM are added to maturation factor. Functionally, when DCs matured in the presence of FEECM elicited stronger MLR, reduced phagocytic activity. These results support the use of the FEECM with MCM, TNF-α and poly (I–C) as maturation factor in DC generation that could result in functionally mature monocyte-derived DCs in comparison to either alone. 相似文献
86.
Sedigheh Ahmadi-Sakha Mohsen Sharifi Vahid Niknam Najmeh Ahmadian-Chashmi 《In vitro cellular & developmental biology. Plant》2018,54(4):444-453
Variation in levels of phenolic acids and flavonoids in Scrophularia striata Boiss. cells cultured in both shake flask and bioreactor in vitro systems, was studied at different growth phases. Four phenolic acids (cinnamic, salicylic, coumaric, and caffeic acid), one stilbenoid (resveratrol), and seven flavonoids (diosmin, rutin, kaempferol, catechin, myricetin, quercetin, and luteolin) were analyzed by high-performance liquid chromatography with photodiode array detection. Production of phenolics in the bioreactor was higher than in shake flasks. Catechin was the most abundant flavonoid in both culture systems, while quercetin, which was detected only in the bioreactor, was the lowest amount represented (32.82 μg g?1 DW). Resveratrol accumulation in bioreactor cultures was 59.84-fold higher than that in shake flasks. Moreover, hierarchical clustering analysis based on Pearson’s correlation coefficient confirmed a positive correlation between the growth phase and some metabolites. The flavonoid accumulation increased with the cells’ physiological age in the bioreactor. Principal component analysis showed that the time course of induction of phenolic acids, flavonoids, and a stilbenoid (resveratrol) was significantly correlated. These findings highlight the capacity of S. striata for large-scale production of desired phenolics using a bioreactor system. 相似文献
87.
Vahid Kazemi Moghaddam Mahmood Yousefi Ahmad Khosravi Mehdi Yaseri Amir Hossein Mahvi Mostafa Hadei Ali Akbar Mohammadi Zahrasadat Robati Adel Mokammel 《Biological trace element research》2018,185(2):262-265
The presence of fluoride in drinking water can be either beneficial or harmful for human health, depending on its concentration. Most adverse effects of fluoride are observed at high concentrations (above 1.5 mg/L). This study was aimed to evaluate the effect of fluoride concentrations in drinking water on spontaneous abortion in two regions: one with low fluoride concentration and another with high fluoride concentration. The results showed that there is a relationship between the concentration of fluoride in drinking water and abortion, so that the risk of abortion increased at high concentrations of fluoride. However, further studies are needed to clarify this relationship due to the small area and population in this study. 相似文献
88.
Essam Abdel-Salam Shaalan Deon Vahid Canyon Mohamed Wagdy Faried Younes Hoda Abdel-Wahab Abdel-Hamid Mansour 《Journal of vector ecology》2005,30(2):284-288
Increasing insecticide resistance requires strategies to prolong the use of highly effective vector control compounds. The use of combinations of insecticides with other insecticides and phytochemicals is one such strategy that is suitable for mosquito control. In bioassays with Aedes aegypti and Culex annulirostris mosquitoes, binary mixtures of phytochemicals with or without synthetic insecticides produced promising results when each was applied at a LC25 dose. All mixtures resulted in 100% mortality against Cx. annulirostris larvae within 24 h rather than the expected mortality of 50%. All mixtures acted synergistically against Ae. aegypti larvae within the first 24 h except for one mixture that showed an additive effect. We conclude that mixtures are more effective than insecticides or phytochemicals alone and that they enable a reduced dose to be applied for vector control potentially leading to improved resistance management and reduced costs. 相似文献
89.
Esmail Asyabi Azadeh Azhdari Mostafa Dehsangi Michel Gokan Khan Mohsen Sharifi Sayed Vahid Azhari 《Cluster computing》2016,19(2):567-583
Cloud computing environments (CCEs) are expected to deliver their services with qualities in service level agreements. On the other hand, they typically employ virtualization technology to consolidate multiple workloads on the same physical machine, thereby enhancing the overall utilization of physical resources. Most existing virtualization technologies are, however, unaware of their delivered quality of services (QoS). For example, the Xen hypervisor merely focuses on fair sharing of processor resources. We believe that CCEs have got married with traditional virtualization technologies without many traits in common. To bridge the gap between these two technologies, we have designed and implemented Kani, a QoS-aware hypervisor-level scheduler. Kani dynamically monitors the quality of delivered services to quantify the deviation between desired and delivered levels of QoS. Using this information, Kani determines how to allocate processor resources among running VMs so as to meet the expected QoS. Our evaluations of Kani scheduler prototype in Xen show that Kani outperforms the default Xen scheduler namely the Credit scheduler. For example, Kani reduces the average response time to requests to an Apache web server by up to \(93.6\,\%\); improves its throughput by up to \(97.9\,\%\); and mitigates the call setup time of an Asterisk media server by up to \(96.6\,\%\). 相似文献
90.
Mona Sorahinobar Vahid Niknam Hassan Ebrahimzadeh Hassan Soltanloo Mehrdad Behmanesh Sattar Tahmasebi Enferadi 《Journal of Plant Growth Regulation》2016,35(2):477-491
Head blight caused by Fusarium graminearum (F. graminearum) is one of the major threats to wheat and barley around the world. The importance of this disease is due to a reduction in both grain yield and quality in infected plants. Currently, there is limited knowledge about the physiological mechanisms involved in plant resistance against this pathogen. To reveal the physiological mechanisms underlying the resistance to F. graminearum, spikes of resistant (Sumai3) and susceptible (Falat) wheat cultivars were analyzed 4 days after inoculation, as the first symptoms of pathogen infection appeared. F. graminearum inoculation resulted in a greater induction level and activity of salicylic acid (SA), callose, phenolic compounds, peroxidase, phenylalanine ammonia lyase (PAL), and polyphenol oxidase in resistant versus susceptible cultivars. Soil drench application to spikes of SA, 24 h before inoculation with F. graminearum alleviated Fusarium head blight symptoms in both resistant and susceptible cultivars. SA treated plants showed a significant increment in hydrogen peroxide (H2O2) production, lipid peroxidation, SA, and callose content. SA-induced H2O2 level seems to be related to increased superoxide dismutase and decreased catalase activities. In addition, real-time quantitative PCR analysis showed that SA pretreatment induced expression of PAL genes in both infected and non-infected head tissues of the susceptible and resistant cultivars. Our data showed that soil drench application of SA activates antioxidant defense responses and may subsequently induce systemic acquired resistance, which may contribute to the resistance against F. graminearum. These results provide novel insights about the physiological and molecular role of SA in plant resistance against hemi-biotrophic pathogen infection. 相似文献