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101.
Mohamed Labib Salem Abdel-Aziz A. Zidan Randa Ezz El-Din El-Naggar Mohamed Attia Saad Mohamed El-Shanshory Usama Bakry Mona Zidan 《Human immunology》2021,82(1):36-45
BackgroundRelapse remains a critical challenge in children with acute lymphoblastic leukemia (ALL). The emergence of immunoregulatory cells, including myeloid-derived suppressor cells (MDSCs), and T regulatory (Treg) cells, has been considered one potential mechanism of relapse in children with ALL.AimThis study aimed to address the microRNAs (miRNAs) related to MDSCs and Treg cells and to explore their targeted immunoregulatory pathways.MethodsAffymetrix microarray was used for global miRNA profiling in B-ALL pediatric patients before, during, and after induction of chemotherapy. Bioinformatics analysis was performed on MDSCs and Treg cells-related dysregulated miRNAs, and miR-Pathway analysis was performed to explore their targeted immunoregulatory pathways.Results516 miRNAs were dysregulated in ALL patients as compared to the healthy donor. Among them, 13 miRNAs and 8 miRNAs related to MDSCs and Treg cells, respectively, were common in all patients. Besides, 12 miRNAs were shared between MDSCs and Treg cells; 4 of them were common in all patients. Four immune-related pathways; TNF, TGF-β, FoxO, and Hippo were found implicated.ConclusionOur pilot study concluded certain miRNAs related to MDSCs and Treg cells, these miRNAs were linked to immunoregulatory pathways. Our results open avenues for testing those miRNA as molecular biomarkers for the immunosuppressive tumor microenvironment. 相似文献
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Mohamed A. Salem Rasha Ali Radwan Eman Sherien Mostafa Saleh Alseekh Alisdair R. Fernie Shahira M. Ezzat 《RSC advances》2020,10(52):31511
Aging is an unavoidable fate that afflicts all life, during this process in mammals reactive oxygen species (ROS) are generated which stimulate tyrosinase, elastase and collagenase activities that actively participate in skin aging. Therefore, the maintenance of antioxidant homeostasis is an important anti-aging strategy for skin. Nature has excellent anti-aging remedies that act externally as well as internally to delay the visual signs of aging. In view of this fact, the present study investigates the in vitro anti-aging activity of five medicinal plants belonging to phenolic rich families namely Rosmarinus officinalis, Lavandula officinalis, Matricaria chamomilla, Camellia sinensis and Pelargonium graveolens. The selected plants are those most frequently used in the preparation of ethnomedicinal recipes for the prevention or treatment of aging. The inhibitory effects of the ethanolic and aqueous extracts of the five selected plants on the activity of tyrosinase, elastase, and collagenase enzymes were investigated. Furthermore, the chemical composition of the plants and the antioxidant capacity of their extracts were assessed. The results showed that R. officinalis had the highest total phenolics content which was correlated with its potent antioxidant and anti-aging activities. To pinpoint the active metabolites in the tested extracts, we evaluated the metabolite variations using ultra-performance liquid chromatography coupled with high resolution electrospray ionization-tandem mass spectrometry (UPLC-HR-ESI-MS/MS). Multivariate data analysis (MVDA) revealed that R. officinalis significantly accumulated metabolites from the aromatic diterpenoid, flavonoid and phenolic acid classes. These results indicate that rosemary can be used for further development of topical preparations with anti-aging properties.Aging is an unavoidable fate that afflicts all life, during this process in mammals, reactive oxygen species (ROS) are generated which stimulate tyrosinase, elastase and collagenase activities that actively participate in skin aging. 相似文献
104.
Thulfiqar F. Mutar Ehab Tousson Ezar Hafez Maha Abo Gazia Seham B. Salem 《Environmental toxicology》2020,35(4):528-537
Cancer is the major cause of death and many factors that lead to its occurrences, such as environmental pollution and pesticides and other factors. Ehrlich carcinoma development depends on many things associated with the environment, nutrition, personal habits, and family history. The present study aimed to evaluate the potential protective effects of vitamin B17 (VB17) against Ehrlich ascites carcinoma (EAC) that induced kidney toxicity in female mice. The mice were divided into five groups (first group, control group; second group, VB17 group; third group, EAC group; fourth group, pretreated EAC with VB17; fifth group, cotreated EAC with VB17). Results showed the VB17 in pretreated (G4) and cotreated (G5) groups lead to an improvement in DNA damage and cytological examination, in addition significantly (P < .05) increase in Na+, red blood cell, hemoglobin, hematocrit value, mean corpuscular hemoglobin (MCH), and MCH concentration, whereas significantly (P < .05) decrease in urea, creatinine, K+, platelets, and white blood cells while insignificant (P < .05) changes in mean corpuscular volume when compared to the EAC group. Many histopathological changes were observed in kidney sections in EAC as marked damage and degenerated, glomerular atrophy, the Malpighian corpuscles that lost their characteristic configuration. On the other hand, a moderate improvement and arrangement in the kidney histological structure in pretreated VB17 + EAC, while a mild enhancement and arrangement of the kidney structure in cotreated EAC + VB17. In addition, depletion in renal P53 and PCNA protein expression compared with the EAC group. It could be concluded that VB17 has a potential renal protective effect against EAC cells induced kidney injury. 相似文献
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John W. KunstmanJames M. Healy M.D. Deborah A. ArayaRonald R. Salem M.B.Ch.B. F.A.C.S. 《American journal of surgery》2015,209(6):1053-1062
Background
Diabetes mellitus is postulated to be both a risk factor and manifestation of pancreatic adenocarcinoma. This study evaluated the effects of preoperative glycemic control as determined by hemoglobin A1c (HbA1c) on outcomes following pancreaticoduodenectomy (PD).Methods
A prospective cohort study whereby HbA1c was assessed preoperatively in 243 patients undergoing PD was performed. The primary outcome measure was operative morbidity. Secondary outcomes included individual adverse events, time to dietary resumption, and length of stay.Results
Preoperative HbA1c ranged from 4.0% to 13.5%. Overall morbidity and incidence of specific adverse events were similar regardless of preoperative HbA1c. No correlation between HbA1c and length of stay, dietary resumption, or readmission was observed. Pancreatic fistula formation had a decreased incidence in patients with elevated versus normal HbA1c (2.2% vs 9.6%, P = .083).Conclusions
PD can be safely performed in patients with HbA1c levels suggestive of poor long-term preoperative glycemic control. Medical efforts to optimize HbA1c should not delay resection. 相似文献108.
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