68 results on '"Mehdizadeh, R."'
Search Results
2. Kinematic Evaluation of the Kazerum Fault System within the Zagros Fold-and-Thrust Belt, Iran
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Mehdizadeh, R.
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- 2019
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3. Initial experience of DCTs
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Mehdizadeh, R., Baynes, W., Aldridge, T., Al-Gholmy, M., Srinivasan, B., and Anand, R.
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- 2020
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4. Quantification of water and sewage leakages from urban infrastructure into a shallow aquifer in East Ukraine
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Vystavna, Y., Diadin, D., Rossi, P. M., Gusyev, M., Hejzlar, J., Mehdizadeh, R., and Huneau, F.
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- 2018
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5. Project risk management in construction projects
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Breysse, D, primary, Tepeli, E, additional, Khartabil, F, additional, Taillandier, F, additional, Mehdizadeh, R, additional, and Morand, D, additional
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- 2014
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6. Modeling methodology of the Risk Breakdown Structure for project risk management in construction
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Mehdizadeh, R, primary, Breysse, D, additional, and Chaplain, M, additional
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- 2011
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7. Nonlinear resistor based on a polymer-ceramic composition
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Hashimov, A. M., Hasanli, Sh. M., Mehdizadeh, R. N., Azizova, Sh. M., and Bayramov, Kh. B.
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- 2007
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8. Quantification of water and sewage leakages from urban infrastructure into a shallow aquifer in East Ukraine
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Vystavna, Y. (Y.), Diadin, D. (D.), Rossi, P. M. (P. M.), Gusyev, M. (M.), Hejzlar, J. (J.), Mehdizadeh, R. (R.), and Huneau, F. (F.)
- Subjects
Oxygen isotope ,Sewer ,Urban groundwater ,Water losses ,Deuterium ,Ukraine - Abstract
Leaky water supply and sewer mains can become unmanaged sources of urban groundwater recharge and contamination posing environmental and health risks. Stable isotopes of water and hydrochemical tracer were applied to quantify water and sewage leakages in a shallow aquifer of a large Ukrainian city. Binary and ternary mixing models were used based on the d-excess and chloride concentrations of tap water, rural and urban groundwater to estimate fractions of natural recharge, urban seepage, volumes of water supply and sewage leakages in urban springs. Water supply leakages that recharge aquifer were ~ 3% (6.5 Mm3 a− 1) of the total water supply and strongly correlated with failures on the water infrastructure. Sewage leakages (1.4 Mm3 a− 1) to the aquifer were less in amount than water supply leakages, but induced nitrate and associated contaminants pollution risk of urban groundwater. The proposed method is useful for the pilot evaluation of urban groundwater recharge and contamination and can be applied in other regions worldwide to support the decision-making in water management.
- Published
- 2018
9. Monitoring of Red Tide Development in Persian Gulf and Oman Sea
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Hamzei, S., Dehghani, R., Rabbaniha, M., Mehdizadeh, R., Daryanavard, M., Salarpouri, A., Pahpouri, A., Mortazawi, M.S., Gheib, A., Owfi, F., and IFSRI
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Hormuz strait ,MODIS data ,Red Tide - Abstract
The catastrophic event of red tide has happened in the Strait of Hormuz, the Persian Gulf and Gulf of Oman from late summer 2008 to spring 2009. With its devastating effects, the phenomenon shocked all the countries located in the margin of the Persian Gulf and the Gulf of Oman and caused considerable losses to fishery industries, tourism, and tourist and trade economy of the region. In the maritime cruise carried out by the Persian Gulf and Gulf of Oman Ecological Research Institute, field data, including temperature, salinity, chlorophyll-a, dissolved oxygen were obtained for this research. Satellite information was received from MODIS and MERIS and SeaWiFS sensors. Temperature and surface chlorophyll images were obtained and compared with the field data and data of PROBE model. The results obtained from the present research indicated that with the occurrence of harmful algal blooms (HAB), the Chlorophyll-a and the dissolved oxygen contents increased in the surface water. Maximum algal density was seen in the northern coasts of the Strait of Hormuz. Less concentration of algal density was detected in deep and surface offshore water. Our results show that the occurred algal bloom was the result of seawater temperature drop, water circulation and the adverse environmental pollutions caused by industrial and urban sewages entering the coastal waters in this region of the Persian Gulf ,This red tide phenomenon was started in the Strait of Hormuz and eventually covered about 140,000 km2 of the Persian Gulf and total area of Strait of Hormuz and it survived for 10 months which is a record amongst the occurred algal blooms across the world. Temperature and chlorophyll satellite images were proportionate to the measured values obtained by the field method. This indicates that satellite measurements have acceptable precisions and they can be used in sea monitoring. Published
- Published
- 2018
10. Reliability Evaluation of Regression Model for Estimating Co-seismic Landslide Displacement
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Nadi, B., primary, Askari, F., additional, Farzaneh, O., additional, Fatolahzadeh, S., additional, and Mehdizadeh, R., additional
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- 2019
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11. Surgery: a patient's perspective and lessons learnt
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Mehdizadeh, R., primary
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- 2016
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12. Effects Of Nimodipinee On Cerebral Hemodynamic And Prognosis Of Diffuse Axonal Injury Patients With Repeated Measurements Design
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Fathi Vajargah, K., primary and Mehdizadeh, R., additional
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- 2013
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13. 352 Evaluation of EGFR, VEGFR2, IGF-1R and HIF-1a Expression and Their Prognostic Value in Iranian Triple-negative Breast Cancer Patients
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Mehdizadeh, R., primary, Najafi, S., additional, and Jahanzad, I., additional
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- 2012
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14. Numerical Prediction of Subway Induced Vibrations: Case Study in Iran-Ahwaz City
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Pakbaz, M.S., primary, Mehdizadeh, R., additional, Vafaeian, M., additional, and Bagherinia, K., additional
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- 2009
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15. The effect of ovariectomy and Estrogen replacement on body weight and visceral adipose tissue in rats
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Babaei, P., arsalan damirchi, Honarmand, F., and Mehdizadeh, R.
16. The effect of exercise training program on indexes of adiposity in pre and post-menopausal obese women
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Mehdizadeh, R., Andam, R., Zafari, A., Shangani, S. M., Elham Eftekhari, and Gholami, M.
17. Cardioprotective effect of saffron extract and safranal in isoproterenol-induced myocardial infarction in wistar rats
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Mehdizadeh, R., Parizadeh, M. -R, Khooei, A. -R, Mehri, S., and Hossein Hosseinzadeh
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Saffron ,Myocardial infarction ,Crocus sativus ,Oxidative stress ,lcsh:R ,Lipid peroxidation ,Isoproterenol ,lcsh:Medicine ,Original Article ,Safranal - Abstract
Objective(s): This study was designed to evaluate the cardioprotective effect of Crocus sativus L. (saffron) aqueous extract and safranal, the major constituent of the essential oil of saffron, on lipid peroxidation, biochemical parameters and histopathological findings in isoproterenol (ISO)-induced myocardial infarction in Wistar rats. Materials and Methods: The saffron extract (20, 40, 80 and 160 mg/kg/day IP) or control were administered for 9 days along with ISO (85 mg/kg, SC, at 24 hr interval) on 8th and 9th day in rats. Activities of creatine kinase-muscle, brain (CK-MB) and lactate dehydrogenase (LDH) were measured using standard commercial kits. The level of malondialdehyde in heart tissue was estimated with thiobarbituric acid reactive species test. For histopathological examination, hematoxylin and eosin (H&E) staining was used. Results: ISO administration induced a statistically significant increase (P< 0.001) in serum LDH and CK-MB and a significant increase (P< 0.001) in the levels of thiobarbituric acid reactive substances (TBARs) in the heart as compared to vehicle control rats. Saffron pretreatment (20, 40, 80 and 160 mg/kg IP) or safranal pretreatment (0.025, 0.050, 0.075 ml/kg IP) for 8 days, significantly decreased (P< 0.001) the serum LDH and CK-MB and myocardial lipid peroxidation as compared to ISO- induced rats. Histological findings of the heart sections confirmed myocardial injury with ISO administration and preserved nearly normal tissue architecture with saffron or safranal pretreatment. Conclusion: Saffron and safranal may have cardioprotective effect in ISO-induced myocardial infarction through modulation of oxidative stress in such a way that they maintain the redox status of the cell.
18. Oocyte competence develops: nuclear maturation synchronously with cytoplasm maturation.
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Torkashvand H, Shabani R, Artimani T, Amiri I, Pilehvari S, Torkashvand L, Mehdizadeh R, and Mehdizadeh M
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Human oocyte maturation is a lengthy process that takes place over the course of which oocytes gain the inherent ability to support the next developmental stages in a progressive manner. This process includes intricate and distinct events related to nuclear and cytoplasmic maturation. Nuclear maturation includes mostly chromosome segregation, whereas rearrangement of organelles, storage of mRNAs and transcription factors occur during cytoplasmic maturation.Human oocyte maturation, both in vivo and in vitro, occurs through a process that is not yet fully understood. However, it is believed that the second messenger, cyclic adenosine monophosphate (cAMP), plays a pivotal role in the upkeep of the meiotic blocking of the human oocyte. Relatively high levels of cAMP in the human oocyte are required to maintain meiosis blocked, whereas lower levels of cAMP in the oocyte enable meiosis to resume. Oocyte cAMP concentration is controlled by a balance between adenylate cyclase and phosphodiesterases, the enzymes responsible for cAMP generation and breakdown.In addition to nuclear maturation, the female gamete requires a number of complicated structural and biochemical modifications in the cytoplasmic compartment to be able to fertilize normally. According to ultrastructural studies, during the transition from the germinal vesicle stage to metaphase II (MII), several organelles reorganize their positions. The cytoskeletal microfilaments and microtubules found in the cytoplasm facilitate these movements and regulate chromosomal segregation.The aim of this review is to focus on the nuclear and cytoplasmic maturation by investigating the changes that take place in the process of oocytes being competent for development.
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- 2024
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19. Randomised controlled trial of resorbable versus non-resorbable sutures for lacerations of the face (TORN Face).
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Basyuni S, Ferro A, Jenkyn I, Nugent G, Bennani M, Bennett H, Chu J, Davies M, Hjalmarsson C, Moorhouse K, Bosley R, Mehdizadeh R, Pancharatnam N, Cameron M, Man CB, Moar K, Thompson M, Fowell C, and Santhanam V
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- Humans, Female, Male, Adult, Single-Blind Method, Middle Aged, Patient Satisfaction, Treatment Outcome, Suture Techniques, Cost-Benefit Analysis, Aged, Absorbable Implants, Lacerations surgery, Facial Injuries surgery, Sutures
- Abstract
Facial lacerations are commonly encountered in emergency departments and require effective management to optimise aesthetic outcomes. Non-resorbable sutures are traditionally favoured for their tensile strength and minimal inflammatory response, despite the inconvenience of the required follow up for removal. This single-centre, single-blinded randomised controlled trial aimed to compare the clinical efficacy and cost-effectiveness of resorbable (Vicryl Rapide) versus non-resorbable (Ethilon) sutures for the closure of facial lacerations in adults. Between November 2021 and February 2023, 200 adult patients presenting with facial lacerations were randomly allocated to either resorbable or non-resorbable sutures. Outcomes assessed included aesthetic results via the Visual Analogue Scale (VAS) and Hamilton Scar Scale, patient-reported satisfaction using the Patient Scar Assessment Questionnaire (PSAQ), complication rates, and cost analysis. No significant differences were found in mean VAS scores between the two groups in both modified intention-to-treat and per-protocol analyses. The majority of patients reported high satisfaction levels. Early complication rates were significantly higher in the non-resorbable group at the one-week follow up, with no long-term differences noted. Preliminary cost analysis indicated a more than five-fold cost saving with resorbable sutures. Resorbable sutures provide a viable and cost-effective alternative to non-resorbable sutures for adult facial lacerations, with comparable aesthetic outcomes and patient satisfaction. Their use could reduce healthcare burdens by eliminating the need for follow-up suture removal, supporting broader adoption in clinical practice., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
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- 2024
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20. Changes in the transcriptomic profile of cumulus cells under the influence of cumulus-oocytes complex pre-incubation.
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Govahi A, Eghbali S, Ghiasi NE, Zandieh Z, Ajdary M, Mehdizadeh R, and Mehdizadeh M
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- Humans, Female, Adult, Gene Expression Profiling, Oxidative Phosphorylation, Signal Transduction, Cumulus Cells metabolism, Oocytes metabolism, Transcriptome
- Abstract
Pre-incubation of the cumulus-oocyte complex (COCs) may lead to better function of cumulus cells (CCs) and higher oocyte quality by changing the transcriptomic profile of CCs. 140 cumulus cell samples were isolated from 12 participants and divided into two groups based on pre-incubation time. In the T0 group, the COCs were immediately dissected to separate the CCs from around the oocytes. In the T2 group, CCs were prepared after 2 h of incubation. Then, the transcriptomic profile of the CCs of the non pre-incubation group was compared to the 2-h pre-incubation group. Confirmation of RNA sequencing results was done via qRT‑PCR. The CCs transcriptome analysis showed 17 genes were downregulated and 22 genes upregulated in the T2 group compared to the T0 group. Also, the pathways related to ATP production (oxidative phosphorylation, electron transport chain, and Mitochondrial complex I assembly model OXPHOS system), TNF-alpha signaling pathway, and glucocorticoid receptor pathway increased in the T2 group compared to the T0 group. Also, the TGF-β pathway was decreased in the T2 group compared to the T0 group. This study showed that 2 h pre-incubation leads to changes in important pathways in CCs, which positively affects oocyte quality., (© 2024. The Author(s).)
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- 2024
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21. The effect of temperature and storage time on DNA integrity after freeze-drying sperm from individuals with normozoospermia.
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Kazorgah FM, Govahi A, Dadseresht A, Kenari FNP, Ajdary M, Mehdizadeh R, Derakhshan R, and Mehdizadeh M
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Objective: This study evaluated the effects of temperature and storage time on the quality and DNA integrity of freeze-dried sperm from individuals with normozoospermia., Methods: Normal sperm samples from 15 men aged 24 to 40 years were studied. Each sample was divided into six groups: fresh, freezing (frozen in liquid nitrogen), freeze-dried then preserved at room temperature for 1 month (FD-1m-RT), freeze-dried then preserved at room temperature for 2 months (FD-2m-RT), freeze-dried then preserved at 4 °C for 1 month (FD-1m-4 °C), and freeze-dried then preserved at 4 °C for 2 months (FD-2m-4 °C). The morphology, progressive motility, vitality, and DNA integrity of the sperm were evaluated in all groups., Results: In all freeze-dried groups, sperm cells were immotile after rehydration. The freeze-dried groups also showed significantly less sperm vitality than the fresh and frozen groups. Significantly more morphological sperm abnormalities were found in the freeze-dried groups, but freeze-drying did not lead to a significantly higher DNA fragmentation index (DFI). The DFI was significantly higher in the FD-2m-RT group than in the other freeze-dried groups., Conclusion: The freeze-drying method preserved the integrity of sperm DNA. The temperature and duration of storage were also identified as factors that influenced the DFI. Accordingly, more research is needed on ways to improve sperm quality in the freeze-drying process.
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- 2024
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22. The Effect of Vitamin D3 Supplemented with PhytoSolve on Genes Involved in Implantation in an NMRI Mice Model of Polycystic Ovary Syndrome: An Experimental Study.
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Hakimpour S, Govahi A, Eghbali S, Shabani R, Mehdizadeh R, Ajdary M, and Mehdizadeh M
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Objective: Vitamin D3 has been shown to be effective in the treatment of PCOS. However, due to its poor solvability and bioavailability, effective time is delayed and dosage requirements are increased. In our previous study, we demonstrated that PhytoSolve containing VD3 is more effective than vitamin D3 alone in the treatment of PCOS. In this study, we aimed to investigate the effect of this vitamin D3 formulation on gene expression involved in implantation in patients with PCOS., Methods: To create PhytoSolve, Lipid S75, glycerol, and MCT oil were combined using a sonicator probe. Six groups, each consisting of 36 female Naval Medical Research Institute (NMRI) mice, were included in the following groups: control; sham; PCOS; PhytoSolve; PhytoSolve containing VD3; and vitamin D3. The mice were given DHEA injections to induce PCOS. After administering PhytoSolve containing VD3 and vitamin D3 by gavage for one week from the 13th day of model creation, the female mice were mated and endometrial tissue was collected for analysis of LIF, β-integrin, and HOXA10 proteins and genes., Results: Compared to the group receiving vitamin D3 alone, the group receiving PhytoSolve containing vitamin D3 showed a significant increase in the expression of LIF, β-integrin, and HOXA10 genes (p<0.05). Although there was an increase in the expression of β-integrin and HOXA10 proteins in the group given PhytoSolve containing vitamin D3 compared to the group given vitamin D3, this increase was not significant. However, the increase in LIF protein expression in the group given PhytoSolve containing vitamin D3 was significant when compared to the group given vitamin D3 (p<0.05)., Conclusions: The use of PhytoSolve containing vitamin D3 was more effective than vitamin D3 alone. The PhytoSolve formulation might be a useful solution for medications with limited solubility and bioavailability.
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- 2023
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23. Cross-talk between non-ionizing electromagnetic fields and metastasis; EMT and hybrid E/M may explain the anticancer role of EMFs.
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Mehdizadeh R, Madjid Ansari A, Forouzesh F, Ghadirian R, Shahriari F, Shariatpanahi SP, and Javidi MA
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- Cell Line, Tumor, Phosphatidylinositol 3-Kinases, Electromagnetic Fields, Cell Movement, Signal Transduction, Epithelial-Mesenchymal Transition
- Abstract
Recent studies have shown that non-ionizing electromagnetic fields (NIEMFs) in a specific frequency, intensity, and exposure time can have anti-cancer effects on various cancer cells; however, the underlying precise mechanism of action is not transparent. Most cancer deaths are due to metastasis. This important phenomenon plays an inevitable role in different steps of cancer including progression and development. It has different stages including invasion, intravasation, migration, extravasation, and homing. Epithelial-mesenchymal transition (EMT), as well as hybrid E/M state, are biological processes, that involve both natural embryogenesis and tissue regeneration, and abnormal conditions including organ fibrosis or metastasis. In this context, some evidence reveals possible footprints of the important EMT-related pathways which may be affected in different EMFs treatments. In this article, critical EMT molecules and/or pathways which can be potentially affected by EMFs (e.g., VEGFR, ROS, P53, PI3K/AKT, MAPK, Cyclin B1, and NF-кB) are discussed to shed light on the mechanism of EMFs anti-cancer effect., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)
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- 2023
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24. Oestrogen treatment restores dentate gyrus development in premature newborns by IGF1 regulation.
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Sharma DR, Cheng B, Sahu R, Zhang X, Mehdizadeh R, Singh D, Iacobas D, and Ballabh P
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- Animals, Rabbits, Tetrahydronaphthalenes, Receptors, Estrogen, Disks Large Homolog 4 Protein genetics, Dentate Gyrus, Estrogen Receptor alpha, Estrogens
- Abstract
Prematurely-born infants cared for in the neonatal units suffer from memory and learning deficits. Prematurity diminishes neurogenesis and synaptogenesis in the hippocampal dentate gyrus (DG). This dysmaturation of neurons is attributed to elevated PSD95, NMDR2A, and IGF1 levels. Since oestrogen treatment plays key roles in the development and plasticity of DG, we hypothesized that 17β-estradiol (E2) treatment would ameliorate neurogenesis and synaptogenesis in the DG, reversing cognitive deficits in premature newborns. Additionally, E2-induced recovery would be mediated by IGF1 signalling. These hypotheses were tested in a rabbit model of prematurity and nonmaternal care, in which premature kits were gavage-fed and reared by laboratory personnel. We compared E2- and vehicle-treated preterm kits for morphological, molecular, and behavioural parameters. We also treated kits with oestrogen degrader, RAD1901, and assessed IGF1 signalling. We found that E2 treatment increased the number of Tbr2
+ and DCX+ neuronal progenitors and increased the density of glutamatergic synapses in the DG. E2 treatment restored PSD95 and NMDAR2A levels and cognitive function in preterm kits. Transcriptomic analyses showed that E2 treatment contributed to recovery by influencing interactions between IGF1R and neurodegenerative, as well as glutamatergic genes. ERα expression was reduced on completion of E2 treatment at D7, followed by D30 elevation. E2-induced fluctuation in ERα levels was associated with a reciprocal elevation in IGF1/2 expression at D7 and reduction at D30. ERα degradation by RAD1901 treatment enhanced IGF1 levels, suggesting ERα inhibits IGF1 expression. E2 treatment alleviates the prematurity-induced maldevelopment of DG and cognitive dysfunctions by regulating ERα and IGF1 levels., (© 2023 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)- Published
- 2023
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25. P53 status, and G2/M cell cycle arrest, are determining factors in cell-death induction mediated by ELF-EMF in glioblastoma.
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Mehdizadeh R, Madjid Ansari A, Forouzesh F, Shahriari F, Shariatpanahi SP, Salaritabar A, and Javidi MA
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- Humans, Tumor Suppressor Protein p53 genetics, Electromagnetic Fields adverse effects, M Cells, G2 Phase Cell Cycle Checkpoints genetics, Glioblastoma genetics, Glioblastoma pathology
- Abstract
The average survival of patients with glioblastoma is 12-15 months. Therefore, finding a new treatment method is important, especially in cases that show resistance to treatment. Extremely low-frequency electromagnetic fields (ELF-EMF) have characteristics and capabilities that can be proposed as a new cancer treatment method with low side effects. This research examines the antitumor effect of ELF-EMF on U87 and U251 glioblastoma cell lines. Flowcytometry determined the viability/apoptosis and distribution of cells in different phases of the cell cycle. The size of cells was assessed by TEM. Important cell cycle regulation genes mRNA expression levels were investigated by real-time PCR. ELF-EMF induced apoptosis in U87cells much more than U251 (15% against 2.43%) and increased G2/M cell population in U87 (2.56%, p value < 0.05), and S phase in U251 (2.4%) (data are normalized to their sham exposure). The size of U87 cells increased significantly after ELF-EMF exposure (overexpressing P53 in U251 cells increased the apoptosis induction by ELF-EMF). The expression level of P53, P21, and MDM2 increased and CCNB1 decreased in U87. Among the studied genes, MCM6 expression decreased in U251. Increasing expression of P53, P21 and decreasing CCNB1, induction of cell G2/M cycle arrest, and consequently increase in the cell size can be suggested as one of the main mechanisms of apoptosis induction by ELF-EMF; furthermore, our results demonstrate the possible footprint of P53 in the apoptosis induction by ELF-EMF, as U87 carry the wild type of P53 and U251 has the mutated form of this gene., (© 2023. The Author(s).)
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- 2023
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26. Does Gold-Silver Core-Shell Nanostructure with Alginate Coating Induce Apoptosis in Human Lymphoblastic Tumoral (Jurkat) Cell Line?
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Mirsanei JS, Nazari M, Shabani R, Govahi A, Eghbali S, Ajdary M, Mehdizadeh R, Mousavi AS, and Mehdizadeh M
- Abstract
Background: T-cell acute lymphoblastic leukemia (T-ALL) is known as an aggressive malignant disease resulting from the neoplastic alteration of T precursor cells. Although treatment with stringent chemotherapy regimens has achieved an 80% cure rate in children, it has been associated with lower success rates in adult treatment. Silver nanoparticles (Ag-NPs) have a toxic effect on human breast cancer cells, human glioblastoma U251 cells, and chronic myeloid leukemia cells in vitro. This study aimed to investigate the effect of Ag nanostructures (Ag-NSs) on Jurkat cells' viability and apoptosis., Methods: The Jurkat cell line was acquired. Following the synthesis Ag-NSs and their characterization, they were incubated with Jurkat cells at different doses for 24, 48, and 72 hours to determine the optimal time and dose. Two groups were examined: a control group with Jurkat cells without nanostructure maintained in the same medium as the cells in the treatment group without changing the medium, and a treatment group with cells treated with the Ag nanostructure solution at a dose of 75 µg/ml for 48 hours according to the MTT results. After 48 hours, the cells from the two groups were used for the q RT-PCR of the apoptotic genes ( BAX , BCL-2 , and CASPASE-3 )., Results: According to our results, the rod-shaped silver nanostructures had a size of about 50 nm, increased apoptotic markers, including BAX and CASPASE-3, and induced cell death., Conclusions: Ag-NSs have anticancer properties and can induce apoptosis of cells; therefore, they may be a potential candidate for the treatment of T-cell acute lymphoblastic leukemia., Competing Interests: The authors declare that they have no conflicts of interest.
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- 2023
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27. Targeting myeloid-derived suppressor cells in combination with tumor cell vaccination predicts anti-tumor immunity and breast cancer dormancy: an in silico experiment.
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Mehdizadeh R, Shariatpanahi SP, Goliaei B, and Rüegg C
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- Humans, Animals, Mice, Cell Line, Tumor, Immunotherapy, Vaccination, Tumor Microenvironment, Myeloid-Derived Suppressor Cells, Triple Negative Breast Neoplasms metabolism
- Abstract
Among the different breast cancer subsets, triple-negative breast cancer (TNBC) has the worst prognosis and limited options for targeted therapies. Immunotherapies are emerging as novel treatment opportunities for TNBC. However, the surging immune response elicited by immunotherapies to eradicate cancer cells can select resistant cancer cells, which may result in immune escape and tumor evolution and progression. Alternatively, maintaining the equilibrium phase of the immune response may be advantageous for keeping a long-term immune response in the presence of a small-size residual tumor. Myeloid-derived suppressor cells (MDSCs) are activated, expanded, and recruited to the tumor microenvironment by tumor-derived signals and can shape a pro-tumorigenic micro-environment by suppressing the innate and adaptive anti-tumor immune responses. We recently proposed a model describing immune-mediated breast cancer dormancy instigated by a vaccine consisting of dormant, immunogenic breast cancer cells derived from the murine 4T1 TNBC-like cell line. Strikingly, these 4T1-derived dormant cells recruited fewer MDSCs compared to aggressive 4T1 cells. Recent experimental studies demonstrated that inactivating MDSCs has a profound impact on reconstituting immune surveillance against the tumor. Here, we developed a deterministic mathematical model for simulating MDSCs depletion from mice bearing aggressive 4T1 tumors resulting in immunomodulation. Our computational simulations indicate that a vaccination strategy with a small number of tumor cells in combination with MDSC depletion can elicit an effective immune response suppressing the growth of a subsequent challenge with aggressive tumor cells, resulting in sustained tumor dormancy. The results predict a novel therapeutic opportunity based on the induction of effective anti-tumor immunity and tumor dormancy., (© 2023. The Author(s).)
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- 2023
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28. Effects of myo-inositol plus folic acid on ovarian morphology and oocyte quality in PCOS mouse model.
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Haghighi M, Mehdizadeh M, Amjadi F, Zandieh Z, Najafi M, Artimani T, Mohammadi F, and Mehdizadeh R
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- Female, Animals, Mice, Humans, Reactive Oxygen Species, Inositol pharmacology, Oocytes, Glutathione, Testosterone pharmacology, Dehydroepiandrosterone pharmacology, Adenosine Triphosphate pharmacology, Folic Acid pharmacology, Polycystic Ovary Syndrome
- Abstract
Although the role of myo-inositol (MYO) in promoting the oocyte quality of PCOS patients has been documented in human studies; the cellular effects of this supplement on oocytes have not been directly examined due to ethical limitations. In the first phase of this study, MYO dosimetry was carried out simultaneously with the PCOS model development. An effective dose was obtained following the assessment of fasting insulin and testosterone levels using ELISA and ovarian morphology appraisal by histopathology. In the second phase, following the continuous administration of the effective dose of MYO and dehydroepiandrosterone (DHEA), cellular evaluation was performed. The quality of oocytes from superovulation was analyzed by examining maturity and normal morphology percentage using a stereomicroscope, intracellular reactive oxygen species (ROS) and glutathione (GSH) levels using fluorometry, and ATP count evaluation using ELISA. The results revealed that, among the four different MYO concentrations, the 0.36 mg/g dose compared with the DHEA group reduced testosterone levels and large atretic antral follicles (LAtAnF) diameter. This dose also increased the corpus luteum count and the granulosa:theca (G/T)layer thickness ratio in antral follicles. Furthermore, this dose increased mature oocytes and normal morphology percentage, ATP count, and GSH levels; however, it decreased ROS levels in mature oocytes. Our findings provide the grounds for further cellular and molecular studies on the PCOS mouse model, suggesting that the improvement in mitochondrial function and its antioxidant properties is probably one of the mechanisms by which MYO increases oocyte quality.
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- 2023
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29. Cutting-edge techniques provide insights regarding repeated implantation failure patients.
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Govahi A, Nasr-Esfahani MH, Amjadi F, Mahdevar M, Mehdizadeh R, and Mehdizadeh M
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- Time-Lapse Imaging methods, Blastocyst, Embryo Implantation, Embryo, Mammalian
- Abstract
Research Question: Can time-lapse parameters and the transcriptional profile of cumulus cells be used to achieve a more stringent and non-invasive method of embryo assessment and to identify possible factors affecting the embryo's ability to implant in repeated implantation failure (RIF) patients?, Design: A total of 190 embryos from 18 oocyte donors and 145 embryos from 15 RIF patients were evaluated based on time-lapse parameters. Three morphokinetic parameters including T5 (time to reach five cells), T3 (time to reach three cells) and CC2 (time to two to three cells) were recorded for all embryos. Embryos that had all three parameters in the normal range were graded as high quality and comparison between these parameters were compared in high-quality embryos between two groups. The transcriptional profile of cumulus cells related to high-quality embryos of both groups were analysed by RNA sequencing and compared. Finally, the possible relationship between differentially expressed genes and time-lapse parameters was examined., Results: T5 was significantly lower in the RIF group than the donor group (P = 0.011). The cumulus cell transcriptome analysis showed 193 genes were down-regulated and 222 genes up-regulated. The mammalian target of rapamycin and the transforming growth factor beta pathways were significantly increased in the RIF group compared to the donor group (P = 0.007 and 0.01, respectively). Vitamin B12 and fatty acid beta-oxidation pathways were also significantly reduced in the RIF group compared to the donor group (P = 0.006 and 0.01, respectively)., Conclusions: Differences in the transcriptomic profiles of cumulus cells and some morphokinetic parameters may be one of the main factors contributing to unexplained RIF., (Copyright © 2022 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2023
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30. Thymol Nanopolymer Synthesis and Its Effects on Morphine Withdrawal Syndrome in Comparison With Clonidine in Rats.
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Moayeri A, Mehdizadeh R, Karimi E, Aidy A, Ghaneialvar H, and Abbasi N
- Abstract
The drug delivery system is valuable in the treatment of the disease. A nanopolymer as a thymol and Thymbra spicata release system was synthesized and its effects on morphine withdrawal syndrome in comparison with clonidine in rats were studied. The nanopolymer was characterized by different methods, namely, IR, HNMR, CNMR, GPC, DLS, and AFM. Thymol in T. spicata extract was assessed. The loading and release rate of thymol and T. spicata extract on the nanopolymer were evaluated by HPLC. The median lethal dose (LD
50 ) of the T. spicata extract, thymol, extract nanopolymer, and thymol nanopolymer was studied. The frequency of jumping, rearing, and teeth chattering in naloxone-induced morphine withdrawal syndrome was studied. Synthesized nanopolymer was desirable as a carrier for the drug. The loaded amount of extract and thymol on nanopolymer was estimated 55 ± 3.2% and 48 ± 2.6% and the drug released was 71 and 68%, respectively. LD50 of the T. spicata extract, thymol, extract nanopolymer, and thymol nanopolymer was 975, 580, 1,250, and 650 mg/kg, respectively. This study showed that thymol nanopolymer was more effective than clonidine to reduce the frequency of morphine withdrawal symptoms. Our results suggest that T. spicata extract, thymol, extract nanopolymer, and thymol nanopolymer are mighty in reducing the narcotic withdrawal signs. The mechanism of action and therapeutic potential is maybe similar to clonidine., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Moayeri, Mehdizadeh, Karimi, Aidy, Ghaneialvar and Abbasi.)- Published
- 2022
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31. Demographic and socioeconomic disparities of pituitary adenomas and carcinomas in the United States.
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Ghaffari-Rafi A, Mehdizadeh R, Ghaffari-Rafi S, Castillo JA Jr, Rodriguez-Beato FY, and Leon-Rojas J
- Subjects
- Aged, Aged, 80 and over, Ethnicity, Female, Humans, Male, Social Class, United States epidemiology, Adenoma epidemiology, Carcinoma, Pituitary Neoplasms epidemiology
- Abstract
Introduction: Growth of some pituitary tumors is driven by hormones which vary in concentration along the lines of patient socioeconomic status. Thus, pituitary tumors may exhibit disparities in incidence upon stratification by socioeconomic variables. Exploring for these disparities could provide direction in tumor etiology elucidation and identification of healthcare inequalities., Methods: To investigate pituitary adenoma and carcinoma incidence (per 100,000) with respect to sex, age, income, residence, and race/ethnicity, we searched the largest American administrative dataset (1997-2016), the National (Nationwide) Inpatient Sample (NIS), which surveys 20% of United States (US) discharges., Results: Annual national incidence was 2.80 for adenomas and 0.046 for carcinomas. For adenomas, males had an incidence of 2.63, similar (p = 0.17) to females at 2.78; likewise, for carcinomas, males had a statistically equivalent (p = 0.24) incidence at 0.051 to females at 0.041. Amongst age groups, for adenomas incidence progressively rose, peaking 65-84 years old (6.12), before declining. For adenomas and carcinomas respectively, patients with low income had an incidence of 2.66 and 0.044, similar (p = 0.11; p = 0.72) to the 3.01 and 0.041 of middle/high income patients. Incidence was greatest for adenomas amongst urban centers (3.47), followed by rural (3.16) and suburban (3.01) communities. Examining race/ethnicity (p = 0.0000016), for adenomas, incidences amongst Blacks, Asian/Pacific Islanders, Hispanics, and Whites were as follows, respectively: 3.64, 2.57, 2.54, 2.44. Annually, incidence for adenomas was increasing (τ = 0.63, p = 0.00021), but decreasing (τ = -0.60, p = 0.00085) for carcinomas. Specifically, for carcinomas incidence was only decreasing for females and the middle/high income., Conclusion: In the US, time-enduring healthcare disparities were identified for pituitary adenomas and carcinomas, against the background of sociodemographic strata. For carcinomas, annual incidence was declining only for middle/high income patients and females, which supporting prior investigations that low income patients and males are experiencing barriers to definitive treatment for pituitary adenomas. Incidence was also found to be greatest Blacks and urban residents., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2022
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32. Vocalization Development in Geoffroy's bat, Myotis emarginatus (Chiroptera: Vespertilionidae).
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Mehdizadeh R, Eghbali H, and Sharifi M
- Abstract
Postnatal development of vocalization has been studied in a small number of bats, not including the Geoffroy's bat, Myotis emarginatus . In the present study, we investigated vocalization development at a maternity roost of M. emarginatus in Kerend Cave in western Iran by sequential measurement of acoustic parameters in known-age neonates using mark-recapture sampling. Newborn pups of M. emarginatus produced both short and isolation calls. Duration of short calls of 1-day-old pups was on average 7.56 ± 0.05 ms and decreased during postnatal development to reach an adult-like duration of 2.78 ± 0.13 ms in the third week. Myotis emarginatus emitted various types of isolation calls, including classic, UP-tail-FM and CF-tail during postnatal growth. As bat pups grew, both short and isolation calls changed in their spectro-temporal structure. Discriminant function analyses showed that each bat pup has a vocal signature that facilitates mother-infant communication. The current study reveals that M. emarginatus pups are highly vocal at birth, but gradually elaborate their sounds with an increase in peak, start and end frequencies as well as with a decrease in call duration throughout the postnatal growth period.
- Published
- 2021
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33. Demographic and socioeconomic disparities of benign cerebral meningiomas in the United States.
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Ghaffari-Rafi A, Mehdizadeh R, Ko AWK, Ghaffari-Rafi S, and Leon-Rojas J
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Brain Neoplasms ethnology, Brain Neoplasms therapy, Female, Humans, Male, Meningeal Neoplasms ethnology, Meningeal Neoplasms therapy, Meningioma ethnology, Meningioma therapy, Middle Aged, Retrospective Studies, United States ethnology, Young Adult, Brain Neoplasms economics, Ethnicity, Healthcare Disparities economics, Income, Meningeal Neoplasms economics, Meningioma economics
- Abstract
Epidemiology provides an avenue for deciphering disease pathogenesis. By determining incidence across socioeconomic and demographic variables in the context of benign cerebral meningiomas (BCM), epidemiologic data may aid in elucidating and addressing healthcare inequalities. To investigate BCM incidence (per 100,000) with respect to sex, age, income, residence, and race/ethnicity, we queried the largest United States (US) administrative dataset (1997-2016), the National (Nationwide) Inpatient Sample (NIS), which surveys 20% of US discharges. Annual national BCM incidence was 5.01. Females had an incidence of 6.78, higher (p = 0.0000038) than males at 3.14. Amongst age groups incidence varied (p = 1.65 × 10
-11 ) and was highest amongst those 65-84 (16.71) and 85+ (18.32). Individuals with middle/high income had an incidence of 5.27, higher (p = 0.024) than the 4.91 of low income patients. Depending on whether patients lived in urban, suburban, or rural communities, incidence varied (χ2 = 8.22, p = 0.016) as follows, respectively: 5.23; 4.96; 5.51. Amongst race/ethnicity (p = 8.15 × 10-14 ), incidence for Whites, Blacks, Asian/Pacific Islanders, Hispanics, and Native Americans were as follows, respectively: 5.05; 4.59; 4.22; 2.99; 0.55. In the US, BCM annual incidence exhibited disparities amongst socioeconomic and demographic subsets. Disproportionately, incidence was greatest for patients who were White, Black, female, 65 and older, and middle/high income., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)- Published
- 2021
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34. Demographic and socioeconomic disparities of benign and malignant spinal meningiomas in the United States.
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Ghaffari-Rafi A, Mehdizadeh R, Ghaffari-Rafi S, and Leon-Rojas J
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Databases, Factual economics, Databases, Factual trends, Female, Healthcare Disparities trends, Humans, Incidence, Male, Middle Aged, Retrospective Studies, Spinal Cord Neoplasms economics, Spinal Cord Neoplasms epidemiology, United States epidemiology, Young Adult, Healthcare Disparities economics, Meningeal Neoplasms economics, Meningeal Neoplasms epidemiology, Meningioma economics, Meningioma epidemiology, Socioeconomic Factors
- Abstract
Introduction: Spinal meningiomas constitute the majority of primary spinal neoplasms, yet their pathogenesis remains elusive. By investigating the distribution of these tumors across sociodemographic variables can provide direction in etiology elucidation and healthcare disparity identification., Methods: To investigate benign and malignant spinal meningioma incidences (per 100,000) with respect to sex, age, income, residence, and race/ethnicity, we queried the largest American administrative dataset (1997-2016), the National (Nationwide) Inpatient Sample (NIS), which surveys 20% of United States (US) discharges., Results: Annual national incidence was 0.62 for benign tumors and 0.056 for malignant. For benign meningiomas, females had an incidence of 0.81, larger (P=0.000004) than males at 0.40; yet for malignant meningiomas, males had a larger (P=0.006) incidence at 0.062 than females at 0.053. Amongst age groups, peak incidence was largest for those 65-84 years old (2.03) in the benign group, but 45-64 years old (0.083) for the malignant group. For benign and malignant meningiomas respectively, individuals with middle/high income had an incidence of 0.67 and 0.060, larger (P=0.000008; P=0.04) than the 0.48 and 0.046 of low income patients. Incidences were statistically similar (P=0.2) across patient residence communities. Examining race/ethnicity (P=0.000003) for benign meningiomas, incidences for Whites, Asian/Pacific Islanders, Hispanics, and Blacks were as follows, respectively: 0.83, 0.42, 0.28, 0.15., Conclusions: Across sociodemographic strata, healthcare inequalities were identified with regards to spinal meningiomas. For benign spinal meningiomas, incidence was greatest for patients who were female, 65-84 years old, middle/high income, living in rural communities, White, and Asian/Pacific Islander. Meanwhile, for malignant spinal meningiomas incidence was greatest for males, those 45-65 years old, and middle/high income., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)
- Published
- 2021
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35. Dormant Tumor Cell Vaccination: A Mathematical Model of Immunological Dormancy in Triple-Negative Breast Cancer.
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Mehdizadeh R, Shariatpanahi SP, Goliaei B, Peyvandi S, and Rüegg C
- Abstract
Triple-negative breast cancer (TNBC) is a molecular subtype of breast malignancy with a poor clinical prognosis. There is growing evidence that some chemotherapeutic agents induce an adaptive anti-tumor immune response. This reaction has been proposed to maintain the equilibrium phase of the immunoediting process and to control tumor growth by immunological cancer dormancy. We recently reported a model of immunological breast cancer dormancy based on the murine 4T1 TNBC model. Treatment of 4T1 cells in vitro with high-dose chemotherapy activated the type I interferon (type I IFN) signaling pathway, causing a switch from immunosuppressive to cytotoxic T lymphocyte-dependent immune response in vivo, resulting in sustained dormancy. Here, we developed a deterministic mathematical model based on the assumption that two cell subpopulations exist within the treated tumor: one population with high type I IFN signaling and immunogenicity and lower growth rate; the other population with low type I IFN signaling and immunogenicity and higher growth rate. The model reproduced cancer dormancy, elimination, and immune-escape in agreement with our previously reported experimental data. It predicted that the injection of dormant tumor cells with active type I IFN signaling results in complete growth control of the aggressive parental cancer cells injected at a later time point, but also of an already established aggressive tumor. Taken together, our results indicate that a dormant cell population can suppress the growth of an aggressive counterpart by eliciting a cytotoxic T lymphocyte-dependent immune response.
- Published
- 2021
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36. Inpatient diagnoses of idiopathic normal pressure hydrocephalus in the United States: Demographic and socioeconomic disparities.
- Author
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Ghaffari-Rafi A, Mehdizadeh R, Ghaffari-Rafi S, and Leon-Rojas J
- Subjects
- Black or African American, Female, Hispanic or Latino, Humans, Male, Socioeconomic Factors, United States epidemiology, White People, Hydrocephalus, Normal Pressure, Inpatients
- Abstract
Introduction: Epidemiology provides an avenue for identifying disease pathogenesis, hence determining national incidence, along with socioeconomic and demographic variables involved in iNPH, can provide direction in elucidating the etiology and addressing healthcare inequalities., Methods: To investigate incidence (per 100,000) of iNPH diagnoses applied to the inpatient population, with respect to sex, age, income, residence, and race/ethnicity, we queried the largest American administrative dataset (2008-2016), the National (Nationwide) Inpatient Sample (NIS), which surveys 20% of United States (US) discharges., Results: Annual national inpatient incidence (with 25th and 75th quartiles) for iNPH diagnoses was 2.86 (2.72, 2.93). Males had an inpatient incidence of 3.27 (3.11, 3.39), higher (p = 0.008) than female at 2.45 (2.41, 2.47). Amongst age groups inpatient incidence varied (p = 0.000004) and was largest amongst the 85+ group at 18.81 (16.40, 19.95). Individuals with middle/high income had an inpatient incidence of 2.96 (2.77, 3.06), higher (p = 0.008) than the 2.37 (2.24, 2.53) of low-income patients. Depending on whether patients lived in urban, suburban, or rural communities, inpatient incidence diverged (p = 0.01) as follows, respectively: 2.65; 2.66; 3.036. Amongst race/ethnicity (p = 0.000003), inpatient incidence for Whites, Blacks, Hispanics, Asian/Pacific Islanders, and Native Americans were as follows, respectively: 3.88 (3.69, 3.93), 1.065 (1.015, 1.14); 0.82 (0.76, 0.85); 0.43 (0.33, 0.52); 0.027 (0.026, 0.12)., Conclusion: In the US, inpatient incidence for iNPH diagnoses exhibited disparities between socioeconomic and demographic strata, emphasizing a healthcare inequality. Disproportionately, diagnoses were applied most to patients who were White, male, 65 and older, middle/high income, and living in rural communities., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2020
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37. Idiopathic Intracranial Hypertension in the United States: Demographic and Socioeconomic Disparities.
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Ghaffari-Rafi A, Mehdizadeh R, Ko AWK, Ghaffari-Rafi S, and Leon-Rojas J
- Abstract
Background: Obesity's risk increases for low-income, female, young, and Black patients. By extrapolation, idiopathic intracranial hypertension (IIH)-a disease associated with body mass index-would potentially display socioeconomic and demographic disparities. Methods: IIH incidence (per 100,000) was investigated with respect to sex, age, income, residence, and race/ethnicity, by querying the largest United States (US) healthcare administrative dataset (1997-2016), the National (Nationwide) Inpatient Sample. Results: Annual national incidence (with 25th and 75th quartiles) for IIH was 1.15 (0.91, 1.44). Females had an incidence of 1.97 (1.48, 2.48), larger ( p = 0.0000038) than males at 0.36 (0.26, 0.38). Regarding age, largest incidence was among those 18-44 years old at 2.47 (1.84, 2.73). Low-income patients had an incidence of 1.56 (1.47, 1.82), larger ( p = 0.00024) than the 1.21 (1.01, 1.36) of the middle/high. No differences (χ
2 = 4.67, p = 0.097) were appreciated between urban (1.44; 1.40, 1.61), suburban (1.30; 1.09, 1.40), or rural (1.46; 1.40, 1.48) communities. For race/ethnicity (χ2 = 57, p = 2.57 × 10-12 ), incidence was largest for Blacks (2.05; 1.76, 2.74), followed by Whites (1.04; 0.79, 1.41), Hispanics (0.67; 0.57, 0.94), and Asian/Pacific Islanders (0.16; 0.11, 0.19). Year-to-year, incidence rose for all strata subsets except Asian/Pacific Islanders (τ = -0.84, p = 0.00000068). Conclusion: IIH demonstrates several sociodemographic disparities. Specifically, incidences are larger for those low-income, Black, 18-44 years old, or female, while annually increasing for all subsets, except Asian/Pacific Islanders. Hence, IIH differentially afflicts the US population, yielding in healthcare inequalities., (Copyright © 2020 Ghaffari-Rafi, Mehdizadeh, Ko, Ghaffari-Rafi and Leon-Rojas.)- Published
- 2020
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38. Application of the sociology theory ethnomethodology to medical education: Utilization of small group learning to combat unconscious bias in patient care.
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Ghaffari-Rafi A, Ghaffari-Rafi S, Lee RE, Aforlabi-Logoh I, Ko AWK, Gadama Y, Mehdizadeh R, and Leon-Rojas J
- Abstract
Competing Interests: All authors declare no conflicts of interest.
- Published
- 2020
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39. Population genetic structure and phylogeography of the greater horseshoe bat ( Rhinolophus ferrumequinum ) along Alborz and Zagros Mts. in Iran.
- Author
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Mehdizadeh R, Akmali V, and Sharifi M
- Subjects
- Animals, Biological Evolution, DNA, Mitochondrial genetics, Evolution, Molecular, Genes, Mitochondrial genetics, Genetic Variation genetics, Genetics, Population methods, Genome, Mitochondrial genetics, Haplotypes genetics, Iran, Mitochondria genetics, Phylogeny, Phylogeography methods, Sequence Analysis, DNA methods, Turkey, Chiroptera genetics, Cytochromes b genetics
- Abstract
In this paper, we investigate the genetic structure and phylogeography of Rhinolophus ferrumequinum , using the mitochondrial cytochrome b gene (1017 bp) in Iran and adjacent regions. The total haplotype and nucleotide diversity are 0.63 ± 0.055 and 0.0021 ± 0.00017, respectively which suggest that R. ferrumequinum exhibits low genetic diversity. AMOVA analysis shows that more variation of genetic differentiation is present among populations of phylogenetic groupings than within populations. Our phylogenetic results support the monophyly of R. ferrumequinum and suggest this taxon comprises three allopatric/parapatric phylogroups that are distributed in Europe-western Turkey, eastern Turkey-northern Iran, and southern Iran. The Europe-western Turkey lineage (clade 2) split from the eastern Turkey-Iran lineage (clade 1) during the middle Pleistocene (0.8534 (ca.I)-0.6454 (ca.II) Ma). The divergence time among subclades A and B occurred during the mid-Pleistocene (0.4849 (ca.I)-0.369 (ca.II) Ma). All phylogenetic analyses also indicate that the Iranian and eastern Turkey R. ferrumequinum diverged from Europe and western Turkey R. ferrumequinum , with the mean percentage sequence differences ranging from 0.92%-0.75% between them. We infer that long-term isolation of R. ferrumequinum in spatially distinct refugia in parts of southwestern and northeastern Iran has promoted distinct phylogeographic lineages during the Pleistocene.
- Published
- 2020
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40. Mitochondrial DNA marker (D-loop) reveals high genetic diversity but low population structure in the pale bent-wing bat (Miniopterus pallidus) in Iran.
- Author
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Mehdizadeh R, Akmali V, and Sharifi M
- Subjects
- Animals, Genetic Markers, Genetics, Population, Iran, Chiroptera genetics, DNA, Mitochondrial genetics
- Abstract
This study investigates the population genetic structure of Miniopterus pallidus using the D-loop region of mitochondrial DNA (331 bp) from 13 localities in Iran. We found a high number of haplotypes (N = 43) and high nucleotide diversity (π = 0.02). The average K2P genetic distance was high within (2.59%) and between (2.54%) the Iranian populations of M. pallidus and analysis of molecular variance revealed that most genetic variability was related to differences within populations. The positive and significant association between pairwise genetic and environmental distances (r = 0.443, p = .01) after accounting for the effect of geographical distances suggests that substantial influence of the climatic factors among different sites have shaped the genetic variation in this species. Neutrality tests showed historical demographic events when applying Fu's Fs, but Tajima's statistic was nonsignificant, indicating a deviation from the theoretical model of expansion. The hypothesis of sudden-expansion was not rejected by analyses of mismatch distribution as the Raggedness and SSD were insignificant (p(r)= .39 and p(SSD) = .38). Similarly, BSP results approximately revealed a major historical expansion around 81,000 years ago and a recent population decline around 13,000 years ago. Phylogenetic trees illustrated that all Iranian M. pallidus populations, as well as those from eastern Turkey and Azerbaijan, form a monophyletic clade, whereas the samples from western Turkey, Georgia and Greece belong to M. schreibersii clade. The haplotype network was consistent with these findings for M. pallidus populations in Iran and showed a high level of reticulation.
- Published
- 2019
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41. Estrogen Treatment Reverses Prematurity-Induced Disruption in Cortical Interneuron Population.
- Author
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Panda S, Dohare P, Jain S, Parikh N, Singla P, Mehdizadeh R, Klebe DW, Kleinman GM, Cheng B, and Ballabh P
- Subjects
- Animals, Animals, Newborn, Calbindin 2 analysis, Cell Count, Female, Gestational Age, Glutamate Decarboxylase analysis, Humans, Infant, Newborn, Infant, Premature, Interneurons chemistry, Interneurons classification, Interneurons physiology, Male, Nerve Tissue Proteins analysis, Nerve Tissue Proteins biosynthesis, Nerve Tissue Proteins genetics, Neuropeptide Y analysis, Parvalbumins analysis, Rabbits, Somatostatin analysis, Transcription Factors biosynthesis, Transcription Factors genetics, Cerebral Cortex pathology, Estradiol pharmacology, Infant, Premature, Diseases pathology, Interneurons drug effects
- Abstract
Development of cortical interneurons continues until the end of human pregnancy. Premature birth deprives the newborns from the supply of maternal estrogen and a secure intrauterine environment. Indeed, preterm infants suffer from neurobehavioral disorders. This can result from both preterm birth and associated postnatal complications, which might disrupt recruitment and maturation of cortical interneurons. We hypothesized that interneuron subtypes, including parvalbumin-positive (PV
+ ), somatostatin-positive (SST+ ), calretinin-positive (CalR+ ), and neuropeptide Y-positive (NPY+ ) interneurons, were recruited in the upper and lower cortical layers in a distinct manner with advancing gestational age. In addition, preterm birth would disrupt the heterogeneity of cortical interneurons, which might be reversed by estrogen treatment. These hypotheses were tested by analyzing autopsy samples from premature infants and evaluating the effect of estrogen supplementation in prematurely delivered rabbits. The PV+ and CalR+ neurons were abundant, whereas SST+ and NPY+ neurons were few in cortical layers of preterm human infants. Premature birth of infants reduced the density of PV+ or GAD67+ neurons and increased SST+ interneurons in the upper cortical layers. Importantly, 17 β-estradiol treatment in preterm rabbits increased the number of PV+ neurons in the upper cortical layers relative to controls at postnatal day 14 (P14) and P21 and transiently reduced SST population at P14. Moreover, protein and mRNA levels of Arx, a key regulator of cortical interneuron maturation and migration, were higher in estrogen-treated rabbits relative to controls. Therefore, deficits in PV+ and excess of SST+ neurons in premature newborns are ameliorated by estrogen replacement, which can be attributed to elevated Arx levels. Estrogen replacement might enhance neurodevelopmental outcomes in extremely preterm infants. SIGNIFICANCE STATEMENT Premature birth often leads to neurodevelopmental delays and behavioral disorders, which may be ascribed to disturbances in the development and maturation of cortical interneurons. Here, we show that preterm birth in humans is associated with reduced population of parvalbumin-positive (PV+ ) neurons and an excess of somatostatin-expressing interneurons in the cerebral cortex. More importantly, 17 β-estradiol treatment increased the number of PV+ neurons in preterm-born rabbits, which appears to be mediated by an elevation in the expression of Arx transcription factor. Hence the present study highlights prematurity-induced reduction in PV+ neurons in human infants and reversal in their population by estrogen replacement in preterm rabbits. Because preterm birth drops plasma estrogen level 100-fold, estrogen replacement in extremely preterm infants might improve their developmental outcome and minimize neurobehavioral disorders., (Copyright © 2018 the authors 0270-6474/18/387378-14$15.00/0.)- Published
- 2018
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42. Postnatal Growth and Vocalization Development in the Long-fingered Bat, Myotis capaccinii (Chiroptera, Vespertilionidae).
- Author
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Mehdizadeh R, Eghbali H, and Sharifi M
- Abstract
Robab Mehdizadeh, Hojjat Eghbali, and Mozafar Sharifi (2018) We simultaneously monitored postnatal growth and vocalization development in a free living population of the long-fingered bat, Myotis capaccinii , in a maternity colony in the Mahidasht cave, western Iran. Length of forearm and body mass of 1-day-old neonates averaged 19.59 ± 1.23 mm and 3.59 ± 0.23 g and followed linear pattern of growth at mean growth rates of 0.74 mm/day and 0.15 g/day until 28 days of age, after which is increased slowly. A similar nonlinear growth pattern was found for ten wing characteristics (wingspan, wing area, handwing length, handwing area, armwing length, armwing area, aspect ratio, wing loading, tip length ratio, and tip area ratio). However, postnatal growth followed a two phase linear pattern of increase-decrease for the epiphyseal-phalangeal gap and decrease- increase for wing loading. At birth, infant bats produced low, short frequency sonar and oral calls in isolation before they could open their eyes. Isolation calls obtained at age 1-4 days old from M. capaccinii pups were frequency modulated shallow calls with longer duration (7.54 ± 1.83 ms) and lower peak frequency (20.07 ± 0.89 kHz) compared to adult female calls (2.35 ± 0.75 ms and 54.02 ± 4.34 kHz). During days 12-16, calls began to resemble adult echolocation calls. Duration of calls increased slightly before 7 days old and then gradually decreased. The peak, start and end frequencies of spontaneous calls increased with age. When the juvenile bats started foraging outside the cave, they only omitted nasal FM calls with 1-2 harmonics. Comparing postnatal changes in body and wing characteristics with those of vocalization, we found that the most positive correlation was between body (forearm length and body mass) and wing features (wing area, wingspan, handwing area, armwing area and aspect ratio) and call parameters (peak, start and end frequency), while wing loading had a significant negative correlation with the call parameters.
- Published
- 2018
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43. Disruption of Interneuron Neurogenesis in Premature Newborns and Reversal with Estrogen Treatment.
- Author
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Tibrewal M, Cheng B, Dohare P, Hu F, Mehdizadeh R, Wang P, Zheng D, Ungvari Z, and Ballabh P
- Subjects
- Animals, Female, Ganglia cytology, Ganglia growth & development, Ganglia metabolism, Homeodomain Proteins metabolism, Hypoxia, Brain chemically induced, Hypoxia, Brain pathology, Ki-67 Antigen metabolism, Neural Stem Cells metabolism, Pregnancy, Premature Birth, Proto-Oncogene Proteins c-myc biosynthesis, Proto-Oncogene Proteins c-myc genetics, Rabbits, SOXB1 Transcription Factors metabolism, Thyroid Nuclear Factor 1 metabolism, Animals, Newborn physiology, Estrogens therapeutic use, Interneurons drug effects, Neurogenesis drug effects
- Abstract
Many Preterm-born children suffer from neurobehavioral disorders. Premature birth terminates the hypoxic in utero environment and supply of maternal hormones. As the production of interneurons continues until the end of pregnancy, we hypothesized that premature birth would disrupt interneuron production and that restoration of the hypoxic milieu or estrogen treatment might reverse interneuron generation. To test these hypotheses, we compared interneuronal progenitors in the medial ganglionic eminences (MGEs), lateral ganglionic eminences (LGEs), and caudal ganglionic eminences (CGEs) between preterm-born [born on embryonic day (E) 29; examined on postnatal day (D) 3 and D7] and term-born (born on E32; examined on D0 and D4) rabbits at equivalent postconceptional ages. We found that both total and cycling Nkx2.1
+ , Dlx2+ , and Sox2+ cells were more abundant in the MGEs of preterm rabbits at D3 compared with term rabbits at D0, but not in D7 preterm relative to D4 term pups. Total Nkx2.1+ progenitors were also more numerous in the LGEs of preterm pups at D3 compared with term rabbits at D0. Dlx2+ cells in CGEs were comparable between preterm and term pups. Simulation of hypoxia by dimethyloxalylglycine treatment did not affect the number of interneuronal progenitors. However, estrogen treatment reduced the density of total and proliferating Nkx2.1+ and Dlx2+ cells in the MGEs and enhanced Ascl1 transcription factor. Estrogen treatment also reduced Ki67, c-Myc, and phosphorylation of retinoblastoma protein, suggesting inhibition of the G1-to-S phase transition. Hence, preterm birth disrupts interneuron neurogenesis in the MGE and estrogen treatment reverses interneuron neurogenesis in preterm newborns by cell-cycle inhibition and elevation of Ascl1. We speculate that estrogen replacement might partially restore neurogenesis in human premature infants. SIGNIFICANCE STATEMENT Prematurity results in developmental delays and neurobehavioral disorders, which might be ascribed to disturbances in the development of cortical interneurons. Here, we show that preterm birth disrupts interneuron neurogenesis in the medial ganglionic eminence (MGE) and, more importantly, that estrogen treatment reverses this perturbation in the population of interneuron progenitors in the MGE. The estrogen seems to restore neurogenesis by inhibiting the cell cycle and elevating Ascl1 expression. As preterm birth causes plasma estrogen level to drop 100-fold, the estrogen replacement in preterm infants is physiological. We speculate that estrogen replacement might ameliorate disruption in production of interneurons in human premature infants., (Copyright © 2018 the authors 0270-6474/18/381100-14$15.00/0.)- Published
- 2018
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44. Treatment Outcomes and Clinicopathologic Characteristics of Triple-Negative Breast Cancer: A Report from Cancer Institute of Iran.
- Author
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Mirzania M, Safaee SR, Shahi F, Jahanzad I, Zahedi G, and Mehdizadeh R
- Abstract
Background: Triple-negative breast cancers (TNBC) have a more aggressive course and are associated with poorer prognosis in comparison with other subtypes of breast cancer. One of the most common subtypes of TNBC is basal-like. The aim of this study was to investigate clinicopathological characteristics and clinical course of TNBC in Iranian women and compare them with other studies. Subjects and Methods: Between March 2009 and February 2011, patients with breast cancer in Cancer Institute of Iran were selected and then followed-up for 2 years. Paraffin-embedded tumor block of all TNBC patients were evaluated for CK5/6 and EGFR using IHC method. Results: Among 267 breast cancer patients, 60 cases with TNBC were identified (22.5%), 31 patients (51.7%) had basal-like and 29 patients (48.3%) had non-basal-like tumors. The median age of participants with TNBC was 49.6 years. Among our patients, 70% had positive lymph nodes.93.4% of all patients at the time of diagnosis were stage II or III and tumor size was at least 3 centimeters. No grade 1 TNBC was found in this study. During the follow-up period, there were 26 recurrences and 7 deaths. Conclusion: The percentage of basal-like subtype among Iranian women with TNBC was lower compared to other studies, while bone metastases, clinical stage, lymph node involvement and tumor size were higher. Clinicopathological findings in basal and non-basal-like subgroups were not different, but the probability of lymph node involvement was more common in patients who were EGFR positive.
- Published
- 2017
45. Epidermal growth factor preserves myelin and promotes astrogliosis after intraventricular hemorrhage.
- Author
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Vinukonda G, Hu F, Mehdizadeh R, Dohare P, Kidwai A, Juneja A, Naran V, Kierstead M, Chawla R, Kayton R, and Ballabh P
- Subjects
- Age Factors, Animals, Animals, Newborn, Astrocytes ultrastructure, Brain embryology, Brain growth & development, Brain pathology, Cell Proliferation drug effects, Cell Proliferation genetics, Cerebral Intraventricular Hemorrhage chemically induced, Disease Models, Animal, Embryo, Mammalian, Gene Expression Regulation physiology, Glial Fibrillary Acidic Protein metabolism, Humans, Infant, Newborn, Infant, Premature, Ki-67 Antigen metabolism, Oligodendrocyte Transcription Factor 2 metabolism, Oligodendroglia pathology, Oligodendroglia ultrastructure, Rabbits, Signal Transduction physiology, Astrocytes drug effects, Cerebral Intraventricular Hemorrhage complications, Cerebral Intraventricular Hemorrhage pathology, Epidermal Growth Factor pharmacology, Gliosis etiology, Myelin Sheath metabolism
- Abstract
Intraventricular hemorrhage (IVH) leads to reduced myelination and astrogliosis of the white matter in premature infants. No therapeutic strategy exists to minimize white matter injury in survivors with IVH. Epidermal growth factor (EGF) enhances myelination, astrogliosis, and neurologic recovery in animal models of white matter injury. Here, we hypothesized that recombinant human (rh) EGF treatment would enhance oligodendrocyte precursor cell (OPC) maturation, myelination, and neurological recovery in preterm rabbits with IVH. In addition, rhEGF would promote astrogliosis by inducing astroglial progenitor proliferation and GFAP transcription. We tested these hypotheses in a preterm rabbit model of IVH and evaluated autopsy samples from human preterm infants. We found that EGF and EGFR expression were more abundant in the ganglionic eminence relative to the cortical plate and white matter of human infants and that the development of IVH reduced EGF levels, but not EGFR expression. Accordingly, rhEGF treatment promoted proliferation and maturation of OPCs, preserved myelin in the white matter, and enhanced neurological recovery in rabbits with IVH. rhEGF treatment inhibited Notch signaling, which conceivably contributed to OPC maturation. rhEGF treatment contributed to astrogliosis by increasing astroglial proliferation and upregulating GFAP as well as Sox9 expression. Hence, IVH results in a decline in EGF expression; and rhEGF treatment preserves myelin, restores neurological recovery, and exacerbates astrogliosis by inducing proliferation of astrocytes and enhancing transcription of GFAP and Sox9 in pups with IVH. rhEGF treatment might improve the neurological outcome of premature infants with IVH. GLIA 2016;64:1987-2004., Competing Interests: Nothing to report., (© 2016 Wiley Periodicals, Inc.)
- Published
- 2016
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46. Interleukin-6, a reliable prognostic factor for ischemic stroke.
- Author
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Shaafi S, Sharifipour E, Rahmanifar R, Hejazi S, Andalib S, Nikanfar M, Baradarn B, and Mehdizadeh R
- Abstract
Background: Interleukin-6 (IL-6) is one of the inflammatory mediators characterized by elevated levels in ischemic stroke (IS) patients. The present study set out to assess the role of IL-6, as a marker for inflammation, in the severity and prognosis of acute IS., Methods: In a cross-sectional descriptive study, 45 patients with acute IS were selected. Patients with their first day of stroke were included in the study. National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS) for stroke severity were evaluated on Days 1, 5, 90, and 365. Serum IL-6 level was measured by enzyme-linked immunosorbent assay (ELISA) on days 1 and 5., Results: In the present study, 45 patients with a mean age of 77.6 ± 4.9 including 32 (71%) men and 13 (28.9%) women were studied. Death occurred in 2 (4.4%) patients before discharge from the hospital; the others, be that as it may, followed the study until Day 365 with a mortality rate of 6 (13.3%). A positive significant correlation was found between IL-6, and NIHSS and mRS of the patients from the time of admission to the end of the follow-up period (P < 0.001, r = 0.6). Moreover, there was a significant correlation between IL-6 and infarction size in brain magnetic resonance imaging (MRI) scan (P < 0.001, r = 0.7)., Conclusion: The evidence from the present study suggests that IL-6 contributes to determination of severity of ischemic stroke. In addition, IL-6 concentrations affect clinical outcomes in ischemic stroke.
- Published
- 2014
47. Cardioprotective effect of saffron extract and safranal in isoproterenol-induced myocardial infarction in wistar rats.
- Author
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Mehdizadeh R, Parizadeh MR, Khooei AR, Mehri S, and Hosseinzadeh H
- Abstract
Objective(s): This study was designed to evaluate the cardioprotective effect of Crocus sativus L. (saffron) aqueous extract and safranal, the major constituent of the essential oil of saffron, on lipid peroxidation, biochemical parameters and histopathological findings in isoproterenol (ISO)-induced myocardial infarction in Wistar rats., Materials and Methods: The saffron extract (20, 40, 80 and 160 mg/kg/day IP) or control were administered for 9 days along with ISO (85 mg/kg, SC, at 24 hr interval) on 8th and 9th day in rats. Activities of creatine kinase-muscle, brain (CK-MB) and lactate dehydrogenase (LDH) were measured using standard commercial kits. The level of malondialdehyde in heart tissue was estimated with thiobarbituric acid reactive species test. For histopathological examination, hematoxylin and eosin (H&E) staining was used., Results: ISO administration induced a statistically significant increase (P< 0.001) in serum LDH and CK-MB and a significant increase (P< 0.001) in the levels of thiobarbituric acid reactive substances (TBARs) in the heart as compared to vehicle control rats. Saffron pretreatment (20, 40, 80 and 160 mg/kg IP) or safranal pretreatment (0.025, 0.050, 0.075 ml/kg IP) for 8 days, significantly decreased (P< 0.001) the serum LDH and CK-MB and myocardial lipid peroxidation as compared to ISO- induced rats. Histological findings of the heart sections confirmed myocardial injury with ISO administration and preserved nearly normal tissue architecture with saffron or safranal pretreatment., Conclusion: Saffron and safranal may have cardioprotective effect in ISO-induced myocardial infarction through modulation of oxidative stress in such a way that they maintain the redox status of the cell.
- Published
- 2013
48. Synthesis of zinc hydroxide nanocrystals and application as a new electrochemical sensor for determination of selected sympathomimetic drugs.
- Author
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Saghatforoush LA, Mehdizadeh R, Sanati S, and Hasanzadeh M
- Abstract
Zinc hydroxide (Zn(OH)2) nanoparticles with nanocrystal morphology and grain size ~48 nm have been successfully synthesized by using a two-step, template- and surfactant-free method. The synthesized product was characterized by FTIR, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive spectroscopy (EDX). The XRD pattern of zinc oxide confirms formation of the wurtzite structure of Zn(OH)2. For the first time zinc oxide nanostructures have been used for electrocatalytic oxidation and determination of sympathomimetic drugs in aqueous solution. The electrochemical parameters of sympathomimetic drugs were investigated by means of cyclic voltammetry and differential pulse voltammetry as well as flow injection analysis.
- Published
- 2012
49. Effects of ovariectomy and estrogen replacement therapy on visceral adipose tissue and serum adiponectin levels in rats.
- Author
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Babaei P, Mehdizadeh R, Ansar MM, and Damirchi A
- Subjects
- Animals, Blood Glucose metabolism, Cholesterol blood, Cholesterol metabolism, Cholesterol, HDL blood, Cholesterol, HDL metabolism, Estradiol pharmacology, Female, Insulin Resistance, Lipoproteins, LDL blood, Lipoproteins, LDL metabolism, Rats, Rats, Wistar, Triglycerides blood, Triglycerides metabolism, Adiponectin blood, Body Weight, Estradiol analogs & derivatives, Estrogen Replacement Therapy, Intra-Abdominal Fat anatomy & histology, Ovariectomy
- Abstract
Background: Excess visceral adipose tissue accumulation after menopause is closely associated with decreased insulin sensitivity and adiponectin levels., Objective: The purpose of this study was to determine the effect of ovariectomy and estrogen replacement on visceral fat and serum adiponectin levels in ovariectomized (OVX) rats., Method: Forty 11-week-old female Wistar rats were divided into the four following groups (n = 10 rats per group): sham-operated control (SHAM); sedentary OVX (OVX-SED); OVX with estrogen replacement (OVX-ER); and OVX with sesame oil treatment (OVX-C). Rats in OVX-ER and OVX-C groups received 17β-estradiol valerate (30 µg/kg, subcutaneously) and sesame oil as vehicle, five days a week, respectively. All animals were sacrificed after eight weeks of intervention., Results: Ovariectomy after eight weeks increased body weight and visceral fat (P < 0.05) in OVX-SED and OVX-C groups compared with SHAM rats with no change in plasma adiponectin levels. Estrogen replacement in OVX animals decreased body weight (13.4%, P < 0.05) and visceral fat (10.4%). Although they were not statistically significant, adiponectin, insulin sensitivity and lipid profile of OVX rats were ameliorated with estrogen treatment., Conclusion: We conclude that ovarian hormone withdrawal leads to higher body weight and visceral adipose tissue in rats, but surprisingly does not change adiponectin levels. Although a substantial decrease in body weight was achieved by estrogen replacement therapy in OVX animals, the beneficial metabolic effects of weight loss seems to be only mechanical, having a tendency to improve insulin sensitivity without elevating adiponectin production.
- Published
- 2010
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50. The ionic environment determines ribozyme cleavage rate by modulation of nucleobase pK a.
- Author
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Smith MD, Mehdizadeh R, Olive JE, and Collins RA
- Subjects
- Catalysis, Cations chemistry, Hydrogen-Ion Concentration, Endoribonucleases chemistry, Nucleotides chemistry, RNA chemistry, RNA, Catalytic chemistry
- Abstract
Several small ribozymes employ general acid-base catalysis as a mechanism to enhance site-specific RNA cleavage, even though the functional groups on the ribonucleoside building blocks of RNA have pK (a) values far removed from physiological pH. The rate of the cleavage reaction is strongly affected by the identity of the metal cation present in the reaction solution; however, the mechanism(s) by which different cations contribute to rate enhancement has not been determined. Using the Neurospora VS ribozyme, we provide evidence that different cations confer particular shifts in the apparent pK (a) values of the catalytic nucleobases, which in turn determines the fraction of RNA in the protonation state competent for general acid-base catalysis at a given pH, which determines the observed rate of the cleavage reaction. Despite large differences in observed rates of cleavage in different cations, mathematical models of general acid-base catalysis indicate that k (1), the intrinsic rate of the bond-breaking step, is essentially constant irrespective of the identity of the cation(s) in the reaction solution. Thus, in contrast to models that invoke unique roles for metal ions in ribozyme chemical mechanisms, we find that most, and possibly all, of the ion-specific rate enhancement in the VS ribozyme can be explained solely by the effect of the ions on nucleobase pK (a). The inference that k (1) is essentially constant suggests a resolution of the problem of kinetic ambiguity in favor of a model in which the lower pK (a) is that of the general acid and the higher pK (a) is that of the general base.
- Published
- 2008
- Full Text
- View/download PDF
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