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551.
552.
Bita Rasoulian Amin Almasi Elham Hoveizi Zohre Bagher Parisa Hayat Mohammad Taghi Joghataei Seyed Mahdi Rezayat Shima Tavakol 《Journal of cellular physiology》2019,234(8):14246-14258
Two of the most problematic orthopedic and neurosurgeon visits are associated with spine and craniofacial fractures. Therefore, more attention needs to be paid to finding a medicine to repair these fractures. Amongst the most mysterious herbs, Aloe vera stands out. In the present study, the ameliorating function of A. vera on osteogenesis was studied in vitro and in vivo. Osteoblast-like cells were exposed to A. vera, followed by analysis of cell viability, lactate dehydrogenase release, and intracellular reactive oxygen species (ROS) production. The results showed an enhanced cell biocompatibility in a dose-dependent manner due to attenuated intracellular ROS production. Furthermore, a docking study indicated that the strong affinity of A. vera constituents to type I bone morphogenic protein receptor (BMPR1A) without the involvement of the BMPR1A chain B. The induction of osteogenesis prompts extracellular calcium deposition by osteoblasts, which affirms successful in vitro bone regeneration. However, injection of A. vera in rats with critical size calvarial defects induced Runx2, alkaline phosphatase (ALP), OCN, and BMP2 genes overexpression, which led to the formation of victorious bone with enhanced bone density and ALP activity. It is worthy to note that Aloin has the highest affinity to BMPR1A, whereas there are no reports regarding the impact of Aloenin, Aloesin, and γ-sitosterol on osteogenesis. Furthermore, some of them have antitumor potency, and it might be proposed that they are considered as a bone substitute in the osteotomy site of osteosarcoma with the aim of bone recovery and suppression of osteosarcoma. The whole consequences of this investigation manifests the plausibility of using A. vera as an antioxidant and osteoconductive substitute. 相似文献
553.
Elham Tahmasebi Yadollah Yamini Abolfazl Saleh 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2009,877(20-21):1923-1929
The applicability of hollow fiber liquid phase microextraction (HF-LPME) for extraction and preconcentration of trace amounts of pioglitazone (PGL) as an anti-diabetic drug in biological fluids, prior to determination by high-performance liquid chromatography (HPLC), was evaluated. In this technique, the target drug was extracted into di-n-hexyl ether immobilized in the wall pores of a porous hollow fiber from 10 mL of the aqueous sample (source phase, SP) with pH 8.0, and then back extracted into the receiving phase (RP) with pH 2.2 located in the lumen of the hollow fiber. The extraction occurred due to a pH gradient between the two sides of the hollow fiber. After extracting for a prescribed time, 24 μL of the RP solution was taken back into the syringe and injected directly into a HPLC instrument for quantification. The Taguchi orthogonal array (OAD) experimental design with an OA16 (45) matrix was employed to optimize the HF-LPME conditions. Different factors affecting the HF-LPME efficiency such as the nature of organic solvent used to impregnate the membrane, pH of the SP and RP, stirring speed, extraction time and ionic strength were studied and optimized. Under the optimum conditions (di-n-hexyl ether as membrane impregnation solvent, pHs of the SP and RP equal to 8.0 and 2.2, respectively, extraction time of 30 min, stirring speed of 500 rpm and 10% (w/v) NaCl for adjusting the ionic strength), preconcentration factor of 180, linear dynamic range (LDR) of 2.5–250 μg L?1 with good correlation of determination (r2 > 0.998) and limit of detection (LOD) of 1.0 μg L?1 were obtained for the target drug. The percent relative intra-day and inter-day standard deviations (RSDs%) based on five replicate determinations were 4.7 and 15%, respectively. Once LPME was optimized, the performance of the proposed technique was evaluated for the determination of PGL in different types of biological fluids such as plasma and urine samples. The results showed that the proposed HF-LPME method could be successfully applied to determine trace amounts of PGL in biological samples. 相似文献
554.
Youssef-Elabd EM McGee KC Tripathi G Aldaghri N Abdalla MS Sharada HM Ashour E Amin AI Ceriello A O'Hare JP Kumar S McTernan PG Harte AL 《The Journal of nutritional biochemistry》2012,23(1):39-50
A post-prandial increase in saturated fatty acids (SFAs) and glucose (Glc) activates an inflammatory response, which may be prolonged following restoration of physiological SFAs and Glc levels — a finding referred to as ‘metabolic memory'.This study examined chronic and oscillating SFAs and Glc on the inflammatory signalling pathway in human adipose tissue (AT) and adipocytes (Ads) and determined whether Ads are subject to “metabolic memory.”Abdominal (Abd) subcutaneous (Sc) explants and Ads were treated with chronic low glucose (L-Glc): 5.6 mM and high glucose (H-Glc): 17.5 mM, with low (0.2 mM) and high (2 mM) SFA for 48 h. Abd Sc explants and Ads were also exposed to the aforementioned treatment regimen for 12-h periods, with alternating rest periods of 12 h in L-Glc.Chronic treatment with L-Glc and high SFAs, H-Glc and high SFAs up-regulated key factors of the nuclear factor-κB (NFκB) pathway in Abd Sc AT and Ads (TLR4, NFκB; P<.05), whilst down-regulating MyD88. Oscillating Glc and SFA concentrations increased TLR4, NFκB, IKKβ (P<.05) in explants and Ads and up-regulated MyD88 expression (P<.05). Both tumor necrosis factor α and interleukin 6 (P<.05) secretion were markedly increased in chronically treated Abd Sc explants and Ads whilst, with oscillating treatments, a sustained inflammatory effect was noted in absence of treatment.Therefore, SFAs may act as key instigators of the inflammatory response in human AT via NFκB activation, which suggests that short-term exposure of cells to uncontrolled levels of SFAs and Glc leads to a longer-term inflammatory insult within the Ad, which may have important implications for patients with obesity and Type 2 diabetes. 相似文献
555.
Elham Naghshineh Reihaneh Dehghani Mohammadabadi Ferdous Mehrabian Hatav Ghasemi Tehrani Mohammad Javad Tarrahi 《Reports of Biochemistry & Molecular Biology》2022,11(2):358
Background:We set out to explore the effect of intrauterine human chorionic gonadotropin (hCG) instillation by intrauterine insemination (IUI) catheter before embryo transfer (ET) on assisted reproductive technologies (ART) outcomes of infertile women.Methods:One hundred women with infertility who were scheduled for in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles were included in the study. They were randomly devoted to two groups: experimental (n= 50) and control (n= 50). In the experimental group, 500 IU hCG passed into the internal cervical orifice via IUI catheter within 15 minutes before the transfer of fresh or vitrified cleavage-stage embryos. The control group underwent the same ET procedure without prior injection of hCG. Results:None of the outcomes showed a statistically significant difference between the two groups. In the intervention and control groups, respectively, biochemical pregnancies rates were 26% and 18%, implantation rates were 13.5% and 8.6%, clinical pregnancies rates were 22% and 14%, ongoing pregnancies rates were 18% and 14%, and live birth rates were 14% and 12%.Conclusion:Intrauterine injection of hCG via IUI catheter is not recommended in a clinical routine setting at this stage. Future efforts are warranted to further refine the applicability of this modality.Key Words: Assisted reproductive technologies, Embryo transfer, Human chorionic gonadotropin, Intrauterine insemination catheter, Randomized clinical trial 相似文献
556.
Leucanthemum Vulgare Lam. Germination,Growth and Mycorrhizal Symbiosis Under Crude Oil Contamination
Azam Sadat Noori Hassan Zare Maivan Ebrahim Alaie 《International journal of phytoremediation》2014,16(9):962-970
Oil contamination of soil limits plants’ access to water and nutrients. Leucanthemum vulgare colonized by mycorrhizae could provide an effective tool in remedying oil contamination. Seeds of L. vulgare were planted in pots containing soil mixed with petroleum at 0, 2.5, 5, 7.5, and 10% w/w and propagules of mycorrhizal fungi. Plants were grown under ambient conditions for 16 weeks. Seed germination data were collected weekly for three weeks. Mycorrhizal percentage, spore counts, length and weight of roots and shoots were determined after harvesting. Results showed significant differences in seed germination rates between oil-treated, mycorrhizal and non-mycorrhizal plants. The overall germination rate was greater at 7.5% w/w crude oil contamination (ρ = 0.05) in mycorrhizal and non-mycorrhizal pots with significant differences between their respective Root:Shoot ratios (both length and weight). Results of this research showed L. vulgare could be germinated and grown in crude oil contaminated soils and could be used to augment plant establishment as part of phytoremediation practices. 相似文献
557.
Mehdi Nasr Esfahani Mansoureh Hosseini Abbas Nasehi Elham Golkhandan 《Archives Of Phytopathology And Plant Protection》2013,46(15):1864-1873
Root and basal rot disease (RBR) of onion, Fusarium oxysporum f. sp. cepa (FOC), is one of the most important diseases, which cause tremendous losses in onion-growing areas worldwide. In this survey, various onion genotypes, including eight main and dominant Iranian seed sets and two exotic ones, were tested against FOC incidence in greenhouse and field conditions of various growing stages. The incidence of the RBR was determined at three stages, such as early, flowering and seed-setting stages, on the basis of disease severity. The genotypes reacted differentially to FOC within and between various stages with a very high significant level. The genotypes were classified in five scoring scales, accordingly. Highly infected ones tended to be associated with the highest mean scores of 75–100% severity and the least infected genotypes had the lowest scores of 0–10%. Moreover, the examined genotypes were ranked from 1 to 10 according to their markedly differing reactions to FOC at various stages. Variance and cluster analysis also showed similar results among the genotypes with various levels of infections. There was a direct, positive and enhancing correlation for every genotype to infection as the growing stages were reaching to the maturing stage. 相似文献
558.
Infection with an insect virus affects olfactory behaviour and interactions with host plant and natural enemies in an aphid 总被引:1,自引:0,他引:1
Liping Ban Elham Ahmed Velemir Ninkovic Gabriele Delp & Robert Glinwood 《Entomologia Experimentalis et Applicata》2008,127(2):108-117
Aphid ecology and population dynamics are affected by a series of factors including behavioural responses to ecologically relevant chemical cues, capacity for population growth, and interactions with host plants and natural enemies. Using the aphid Rhopalosiphum padi (L.) (Homoptera: Aphididae), we showed that these factors were affected by infection with Rhopalosiphum padi virus (RhPV). Uninfected aphids were attracted to odour of uninfected aphids on the host plant, an aggregation mechanism. However, infected aphids were not attracted, and neither infected nor uninfected aphids were attracted to infected aphids on the plant. Infected aphids did not respond to methyl salicylate, a cue denoting host suitability. Infected aphids were more behaviourally sensitive to aphid alarm pheromone, and left the host plant more readily in response to it. RhPV reduced the lifespan and population growth rate of the aphid. The predacious ladybird, Coccinella septempunctata (L.) (Coleoptera: Coccinellidae), consumed more infected aphids than uninfected aphids in a 24‐h period, and the aphid parasitoid Aphidius ervi Haliday (Hymenoptera: Aphidiidae) attacked more infected than uninfected aphids. However, the proportion of mummies formed was lower with infected aphids. The results represent further evidence that associated organisms can affect the behaviour and ecology of their aphid hosts. 相似文献
559.
Elham Forouzesh Ashwani Goel Sally A. Mackenzie Joseph A. Turner 《The Plant journal : for cell and molecular biology》2013,73(3):509-520
Turgor pressure in plant cells is involved in many important processes. Stable and normal turgor pressure is required for healthy growth of a plant, and changes in turgor pressure are indicative of changes taking place within the plant tissue. The ability to quantify the turgor pressure of plant cells in vivo would provide opportunities to understand better the process of pressure regulation within plants, especially when plant stress is considered, and to understand the role of turgor pressure in cellular signaling. Current experimental methods do not separate the influence of the turgor pressure from the effects associated with deformation of the cell wall when estimates of turgor pressure are made. In this paper, nanoindentation measurements are combined with finite element simulations to determine the turgor pressure of cells in vivo while explicitly separating the cell‐wall properties from the turgor pressure effects. Quasi‐static cyclic tests with variable depth form the basis of the measurements, while relaxation tests at low depth are used to determine the viscoelastic material properties of the cell wall. Turgor pressure is quantified using measurements on Arabidopsis thaliana under three pressure states (control, turgid and plasmolyzed) and at various stages of plant development. These measurements are performed on cells in vivo without causing damage to the cells, such that pressure changes may be studied for a variety of conditions to provide new insights into the biological response to plant stress conditions. 相似文献
560.
Ming Zheng Haili Zhang David L. Dill J. David Clark Susan Tu Arielle L. Yablonovitch Meng How Tan Rui Zhang Dan Rujescu Manhong Wu Lino Tessarollo Wilfred Vieira Michael M. Gottesman Suhua Deng Livia S. Eberlin Richard N. Zare Jean-Martin Billard Jean-Pierre Gillet Jin Billy Li Gary Peltz 《PLoS medicine》2015,12(2)