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921.
Lead (Pb) is one of the most common heavy metal contaminants in the environment. The present study was therefore undertaken to determine the effects of Pb on structural characteristics and hypericin production in Hypericum perforatum. Mature plants were treated with contaminated soil in seven treatments (75, 150, 300, 600, 800, 1000, and 1500 mg/kg Pb in soil) with three repeats per treatment every 14 days. Maximum observed Pb content in shoot parts was observed in the treatments with 600 and 1500 mg/kg Pb. The Pb concentration in roots was higher than in shoot parts, enhanced with increasing Pb concentration in the soil. In this study, Pb treatment significantly influenced the morphology, anatomy, and hypericin content in the plant. Anatomical characteristics of leaf, stem, and root affected by Pb contamination, as well as scanning electron microscopy (SEM) studies, revealed structural changes in stomata and epicuticular waxes. Under Pb toxicity, anatomical symptoms occurred in leaves, including increase in sizes of epidermal cells, mesophyll tissue, and diameter of stems and roots, as well as amplified vascular bundles and pith area. This, therefore, indicated that metal contamination can change the chemical composition of this plant. Maximum hypericin content was observed in the treatment containing 600 mg/kg Pb in soil, which then decreased. 相似文献
922.
923.
Purpose: The aim of this study was to model the relationship between risk factors of postpartum depression and quality of life in Iranian women. Methods: In this study, 306 women were included as a sample. The study tools of the Edinburgh Postpartum Depression Inventory included items such as socioeconomic characteristics, recent pregnancy history and outcome, and Quality of Life Questionnaire (SF-12). SPSS software was used for data analysis and a significance value of 0.05 was considered. Results: Most participants were homemakers with no instances of abortion, no stillbirth, no history of depression, no preterm delivery, no difficulties during pregnancy, no difficulties during delivery, no unplanned pregnancy, no smoking during pregnancy, had family support during pregnancy and after delivery, type of delivery was cesarean, had a healthy baby and satisfaction with neonatal sex, and never or rarely experienced partner violence. Their mean age, years of education, living arrangements, and breastfeeding of participants respectively were 29.73±5.42, 14.64±1.96, 1.09±0.53, and 5.61±2.98. The prevalence of postpartum depression was 5.6%. According to the path analysis, living arrangements with β=0.73 had the most direct effect and occupation with β=0.69 had the most indirect effect on postpartum depression. Conclusions: According to the path analysis model, postpartum depression is affected by many factors such as age, years of education, occupation, living arrangements, and quality of life. 相似文献
924.
Niloufar Abdollahian Hamideh Ghazizadeh Maryam Mohammadi-Bajgiran Mehran Pashirzad Mahdiyeh Yaghooti Khorasani Mary Kathryn Bohn Shannon Steele Fatemeh Roudi Atieh Kamel Khodabandeh Sara Ghazi Zadeh Iman Alami-Arani Seyede Negin Badakhshan Habibollah Esmaily Gordon A. Ferns Reza Assaran-Darban Khosrow Adeli Majid Ghayour-Mobarhan 《Journal of cellular and molecular medicine》2023,27(1):158-162
Age and sex need to be considered in the establishment of reference intervals (RIs), especially in early life when there are dynamic physiological changes. Since data for important biomarkers in healthy neonates and infants are limited, particularly in Iranian populations, we have determined age-specific RIs for 7 laboratory biochemical parameters. This cross-sectional study comprised a total of 344 paediatric participants (males: 158, females: 186) between the ages of 3 days and 30 months (mean age: 12.91 ± 7.15 months). Serum levels of creatinine, urea, uric acid, calcium, phosphate, vitamin D and high-sensitivity C-reactive protein (hs-CRP) were measured using an Alpha classic-AT plus auto-analyser. We determined age-specific RIs using CLSI Ep28-A3 and C28-A3 guidelines. No sex partitioning was required for any of the biomarkers. Age partitioning was required for kidney function tests and phosphate. The serum concentration of urea and creatinine increased with age, while phosphate and uric acid decreased with age. Age partitioning was not required for serum calcium, vitamin D, and hs-CRP, which remained relatively constant throughout the age range. Age-specific RIs for 7 routine biochemical markers were determined to address critical gaps in RIs in early life to help improve clinical interpretation of blood test results in young children, including neonates. Established age partitions demonstrate the biochemical changes that take place during child growth and development. These novel data will ultimately better disease management in the Iranian paediatric population and can be of value to clinical and hospital laboratories with similar populations. 相似文献
925.
Andrew J Locke Lazina Hossain Glynnis McCrostie Daryl A Ronato Amira Fitieh Tanzeem
Ahmed Rafique Fatemeh Mashayekhi Mobina Motamedi Jean-Yves Masson Ismail
Hassan Ismail 《Nucleic acids research》2021,49(2):928
Double-strand breaks and stalled replication forks are a significant threat to genomic stability that can lead to chromosomal rearrangements or cell death. The protein CtIP promotes DNA end resection, an early step in homologous recombination repair, and has been found to protect perturbed forks from excessive nucleolytic degradation. However, it remains unknown how CtIP’s function in fork protection is regulated. Here, we show that CtIP recruitment to sites of DNA damage and replication stress is impaired upon global inhibition of SUMOylation. We demonstrate that CtIP is a target for modification by SUMO-2 and that this occurs constitutively during S phase. The modification is dependent on the activities of cyclin-dependent kinases and the PI-3-kinase-related kinase ATR on CtIP’s carboxyl-terminal region, an interaction with the replication factor PCNA, and the E3 SUMO ligase PIAS4. We also identify residue K578 as a key residue that contributes to CtIP SUMOylation. Functionally, a CtIP mutant where K578 is substituted with a non-SUMOylatable arginine residue is defective in promoting DNA end resection, homologous recombination, and in protecting stalled replication forks from excessive nucleolytic degradation. Our results shed further light on the tightly coordinated regulation of CtIP by SUMOylation in the maintenance of genome stability. 相似文献
926.
927.
928.
Babaee Nikta Talebkhan Garoosi Yeganeh Karimipoor Morteza Davami Fatemeh Bayat Elham Safarpour Hossein Mahboudi Fereidoun Barkhordari Farzaneh 《Molecular biology reports》2020,47(10):7323-7331
Molecular Biology Reports - This study is to investigate the binding ability of Designed Ankyrin Repeat Proteins type Ec1that was fused to Low Molecular Weight Protamine (DARPin Ec1-LMWP) protein... 相似文献
929.
Abstract This research aimed to mitigate fouling in membrane bioreactors (MBR) through concurrent usage of zinc oxide as an antibacterial agent (A) and sodium alginate as a hydrophilic agent (H) within a polyacrylonitrile membrane (PM) structure. The antibacterial polymeric membranes (APM) and antibacterial hydrophilic polymeric membranes (AHPM) synthesized showed a higher porosity, mechanical strength and bacterial inhibition zone, and a lower contact angle in comparison with PM membranes. EDS, SEM and AFM analyses were used to characterize the chemical, structural, and morphological properties of PM, APM, and AHPM. The flux of PM, APM, and AHPM in MBR was 37, 48, and 51?l m?2 h?1 and COD removal was 81, 93.5, and 96.7%, respectively. After MBR operation for 35?days in an urban wastewater treatment, only 50% of the flux of PM was recovered, while the antibacterial and hydrophilic agents yielded a flux recovery of 72.7 and 100% for APM and AHPM, respectively. 相似文献
930.
Mohammad Reza Bayatiani Azam Ahmadi Reza Aghabozorgi Fatemeh Seif 《Reports of Biochemistry & Molecular Biology》2021,9(4):408
Background:The WNT-pathway is involved in several cancers, including colorectal cancer (CRC). Many cell signaling components and pathways are controlled by microRNAs. The main purpose of the present study was to investigate the expression of hsa-miR-374, and its two target genes of the Wnt-pathway in CRC clinical samples.Methods:In this study, we predicted the miRNAs targeting key genes of WNT-pathway using bioinformatics algorithms. The expression levels of hsa-miR-374, APC and GSK-3β on 48 pairs of Formalin-Fixed Paraffin-Embedded (FFPE) CRC tumors and marginal-tumors were evaluated using real time-PCR. Additionally, the hsa-miR-374a-5p precursor sequence was amplified by whole-blood DNA as a template. This amplicon was cloned into pEGFP-c1 expression vector and transfected into SW742 cells. Aside from this, MTT assay was performed to evaluate the effect of miR-374 on cell viability. Results:The bioinformatics analysis indicated that hsa-miR-374 binds to the regulatory region the key components of WNT-pathway, including APC and GSK-3β considering the recognition elements and mirSVR scores. Our results revealed significant down-regulation of GSK-3β (0.94 times, p= 0.0098) and APC (0.96 times, p= 0.03) and up-regulation of miR-374 (1.22 times, p= 0.0071) on tumor samples compared with their normal pairs. Meanwhile, the results of the over-expression of miR-374 showed down-regulation of APC and GSK-3β. MTT-assay also indicated that the miR-374 increased cell survival.Conclusion:The results of our study indicated a concomitant change in the expression of miR-374 and its two related target genes, in clinical samples of CRC. Hsa-miR-374 might be as a helpful biomarker or therapeutic target in CRC.Key Words: Colorectal cancer, GSK-3β, miR-374, WNT 相似文献