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Quercetin and cancer: New insights into its therapeutic effects on ovarian cancer cells
Get PDFOvarian cancer is known as a serious malignancy that affects women's reproductive tract and can considerably threat their health. A wide range of molecular mechanisms and genetic modifications have been involved in ovarian cancer pathogenesis making it difficult to develop effective therapeutic platforms. Hence, discovery and developing new therapeutic approaches are required. Medicinal plants, as a new source of drugs, could potentially be used alone or in combination with other medicines in the treatment of various cancers such as ovarian cancer. Among various natural compounds, quercetin has shown great anti-cancer and anti-inflammatory properties. In vitro and in vivo experiments have revealed that quercetin possesses a cytotoxic impact on ovarian cancer cells. Despite obtaining good results both in vitro and in vivo, few clinical studies have assessed the anti-cancer effects of quercetin particularly in the ovarian cancer. Therefore, it seems that further clinical studies may introduce quercetin as therapeutic agent alone or in combination with other chemotherapy drugs to the clinical setting. Here, we not only summarize the anti-cancer effects of quercetin but also highlight the therapeutic effects of quercetin in the ovarian cancer. © 2020 The Author(s)
Sonochemical synthesis of ErVO4/MnWO4 heterostructures: Application as a novel nanostructured surface for electrochemical determination of tyrosine in biological samples
Get PDFPresent strategy introduces a novel method established for the synthesis of spherical shape ErVO4/MnWO4 heterostructures by a sonochemical method. This heterostructures with optima morphology can be synthesized by changing power and time ultrasound irradiation without any capping agent. BET analysis revealed that ErVO4/MnWO4 prepared in the presence of ultrasonic procedure has 75 times specific surface area as much as that of those was produced in the absence of ultrasonic rays. A variety of analyses (i.e., BET, XRD, TEM, EDS, FT-IR, and SEM) were applied for characterization of the ErVO4/MnWO4. Next, a selective and sensitive nanostructured sensor based on ErVO4/MnWO4 nanocomposite modified carbon paste electrode (ErVO4/MnWO4/CPE) was constructed for electrochemical detection of tyrosine (Tyr). The electrochemical characterizations were performed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). Compared with the unmodified CPE, the oxidation peak current was significantly enhanced for Tyr. The impact of effective parameters on voltammetric response of Tyr was analyzed with design of experiments (DOE) and response surface methodology (RSM). Under the optimized conditions, the oxidation peak current of Tyr was linear over a range of 0.08�400.0 μM with a detection limit of 7.7 nM. Finally, the usage of the proposed method was confirmed by the recovery tests of Tyr in biological samples. © 201
Oxidative stress and male infertility: current knowledge of pathophysiology and role of antioxidant therapy in disease management
No full textInfertility is a global health problem involving about 15 of couples. Approximately half of the infertility cases are related to male factors. The oxidative stress, which refers to an imbalance in levels of reactive oxygen species (ROS) and antioxidants, is one of the main causes of infertility in men. A small amount of ROS is necessary for the physiological function of sperm including the capacitation, hyperactivation and acrosomal reaction. However, high levels of ROS can cause infertility through not only by lipid peroxidation or DNA damage but inactivation of enzymes and oxidation of proteins in spermatozoa. Oxidative stress (OS) is mainly caused by factors associated with lifestyle. Besides, immature spermatozoa, inflammatory factors, genetic mutations and altering levels of sex hormones are other main source of ROS. Since OS occurs due to the lack of antioxidants and its side effects in semen, lifestyle changes and antioxidant regimens can be helpful therapeutic approaches to overcome this problem. The present study aimed to describe physiological ROS production, roles of genetic and epigenetic factors on the OS and male infertility with various mechanisms such as lipid peroxidation, DNA damage, and disorder of male hormone profile, inflammation, and varicocele. Finally, the roles of oral antioxidants and herbs were explained in coping with OS in male infertility. © 2019, Springer Nature Switzerland AG
The properties of nanofiber scaffolds of polyurethane-Cinnamomum zeylanicum against pathogens of Pseudomonas aeruginosa and Staphylococcus aureus
Get PDFThis study designed to investigate the properties of antibacterial nanofiber scaffolds of polyurethane-Cinnamomum zeylanicum against virulence gene expression inhibition of Pseudomonas aeruginosa and Staphylococcus aureus that are important in burn wounds. With attention to burn wound infections in hospitals and mortality increase in patients, it is necessary to design nanodressing. Clinical isolates were confirmed by biochemical and microbiological tests. DNA of isolates was extracted and PCR used to confirm the alp gene of P. aeruginosa and Pv gene of S. aureus. Polyurethane nanofiber and cinnamon polymers were used to prepare the scaffold under the electrospinning process. Infrared spectroscopy, electron microscopy, and mechanical tensile tests were used to confirm the scaffolds. The susceptibility testing and minimum inhibitory concentration of polyurethane-cinnamon nanofiber scaffold were determined against P. aeruginosa and S. aureus. For confirmation of polyurethane-cinnamon nanofiber scaffold were used the cytotoxicity test (MTT), FTIR, mechanical tensile test, and a scanning electron microscope. The expression of virulence genes was investigated using the real-time RT-PCR technique. The results of the susceptibility testing indicated that P. aeruginosa and S. aureus were susceptible to polyurethane-cinnamon nanofiber scaffold. The MTT, FTIR, mechanical tensile test, and SEM confirmed the different features of the polyurethane-cinnamon nanofiber scaffold. Results of real-time PCR demonstrated that the expression levels of p�v and alp genes after treatment decreased, respectively, 2.71- and 1.06-fold. Results indicated that the electrospun polyurethane-cinnamon nanofiber scaffold for the first time could inhibit both important pathogens of the hospital and the expression of the virulence genes. Considering the susceptibility of P. aeruginosa and S. aureus to and its inhibitory effect on an alp and p�v genes, this system could probably be a candidate in wound dressing for commercial purposes to burn healing and infection inhibition. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature
Therapeutic application of nutraceuticals in diabetic nephropathy: Current evidence and future implications
No full textDiabetes mellitus (DM) is a common metabolic disease which may cause several complications, such as diabetic nephropathy (DN). The routine medical treatments used for DM are not effective enough and have many undesirable side effects. Moreover, the global increased prevalence of DM makes researchers try to explore potential complementary or alternative treatments. Nutraceuticals, as natural products with pharmaceutical agents, have a wide range of therapeutic properties in various pathologic conditions such as DN. However, the exact underlying mechanisms have not been fully understood. The purpose of this review is to summarize recent findings on the effect of nutraceuticals on DN. © 2020 John Wiley & Sons Lt
Workplace Conflicts Among Emergency Department Nurses: Instrument Development and Psychometric Properties
No full textBackground and Purpose: Conflicts in nursing workplace are frequent and can be resolved by individuals or groups. The purpose of this study was to develop a valid and reliable measure for the Workplace Conflicts among Emergency Department Nurses (WCEDN). Methods: A three-stage mixed methods study was conducted: (a) In-depth interviews with emergency department (ED) nurses were performed and themes were extracted from the data (b) Findings of the content analysis in combination with results of a literature review were examined, and preliminary instrument items were developed. The initial instrument comprised 50 items. (c) Content validity, face validity, content validity ratio, content validity index, and construct validity using exploratory factor analysis were performed. Results: Subscales in the final instrument included Intrapersonal Conflict, Intragroup Conflict, Intergroup Conflict, and Causes of Conflict. Reliability of the instrument was.86, and the feasibility was 96.8. Conclusions: The final 40-item WCEDN demonstrated strong psychometric properties. © Copyright 2020 Springer Publishing Company, LLC
Targets for protection and mitigation of radiation injury
No full textProtection of normal tissues against toxic effects of ionizing radiation is a critical issue in clinical and environmental radiobiology. Investigations in recent decades have suggested potential targets that are involved in the protection against radiation-induced damages to normal tissues and can be proposed for mitigation of radiation injury. Emerging evidences have been shown to be in contrast to an old dogma in radiation biology; a major amount of reactive oxygen species (ROS) production and cell toxicity occur during some hours to years after exposure to ionizing radiation. This can be attributed to upregulation of inflammatory and fibrosis mediators, epigenetic changes and disruption of the normal metabolism of oxygen. In the current review, we explain the cellular and molecular changes following exposure of normal tissues to ionizing radiation. Furthermore, we review potential targets that can be proposed for protection and mitigation of radiation toxicity. © 2020, Springer Nature Switzerland AG
Molecular and biological functions of melatonin in endometrial cancer
No full textEndometrial cancer is the fifth leading cancer among women. This rate is higher in devel-oped countries and its incidence is increasing worldwide. Diabetes mellitus, obesity, hypertension and arteriosclerosis are major risk factors for endometrial cancer. Melatonin is a hormone synthesized in the pineal and extra-pineal organs such as the digestive tract, bone marrow, retina and more. Evidence shows the potential effects of melatonin in endometrial cancer inhibition. Therefore, the focus of this paper is to review this outstanding evidence and to summarize the molecular and biological mechanisms of melatonin for the inhibition of endometrial cancer. © 2020 Bentham Science Publishers
Association of 25-hydroxy vitamin D with asthma and its severity in children: A case-control study
Get PDFBackground: Universally, asthma has high prevalence rates and this has led numerous studies done into its causes. Despite extensive study on asthma the association between 25-Hydroxy Vitamin D (25(OH) vit. D) and asthma remains uncertain. In this study, the associations of 25(OH) vit. D levels with asthma and with the severity of asthma were evaluated. Methods: This was a case-control study performed in 2015 in the city of Isfahan. In this study 520 children were studied. Children with asthma were classified as cases and children who were referred for reasons other than respiratory problems and asthma were considered as controls. Serum 25 (OH) vit. D levels were then examined and compared between the two groups. Differences among groups were stated to be statistically significant when P-values < 0.05. Results: There were 260 asthmatic children and 260 controls in the present study. The mean 25 (OH) vit. D levels in the case group was 25.5 ± 16.62 and 16.76 ± 31.40 the control group and this difference was statistically significant (P < 0.05). 25(OH) vit. D levels were found to be 28.05 ± 16.98 in non-severe asthma and 21.41 ± 15.20 in severe asthma. Consequently 25(OH) vit. D level had inverse relationship with asthma severity (P = 0.002). Conclusions: As the results of this study showed, the lower level of 25(OH) vit. D correlated with the higher severity of asthma manifestations. Therefore, it is recommended that 25(OH) vit. D levels get routinely checked especially in severe asthma cases and if the deficiency presents, appropriate therapeutic measures be used to reduce the asthma severity. © 2020 The Author(s)
TGF-β in radiotherapy: Mechanisms of tumor resistance and normal tissues injury
Get PDFEmerging evidences show that changes in tumor stroma can adapt cancer cells to radiotherapy, thereby leading to a reduction in tumor response to treatment. On the other hand, radiotherapy is associated with severe reactions in normal tissues which limit the amount radiation dose received by tumor. These challenges open a window in radiobiology and radiation oncology to explore mechanisms for improving tumor response and also alleviate side effects of radiotherapy. Transforming growth factor beta (TGF-β) is a well-known and multitasking cytokine that regulates a wide range of reactions and interactions within tumor and normal tissues. Within tumor microenvironment (TME), TGF-β is the most potent suppressor of immune system activity against cancer cells. This effect is mediated through stimulation of CD4+ which differentiates to T regulatory cells (Tregs), infiltration of fibroblasts and differentiation into cancer associated fibroblasts (CAFs), and also polarization of macrophages to M2 cells. These changes lead to suppression of cytotoxic CD8 + T lymphocytes (CTLs) and natural killer (NK) cells to kill cancer cells. TGF-β also plays a key role in the angiogenesis, invasion and DNA damage responses (DDR) in cancer cells. In normal tissues, TGF-β triggers the expression of a wide range of pro-oxidant and pro-fibrosis genes, leading to fibrosis, genomic instability and some other side effects. These properties of TGF-β make it a potential target to preserve normal tissues and sensitize tumor via its inhibition. In the current review, we aim to explain the mechanisms of upregulation of TGF-β and its consequences in both tumor and normal tissues. © 2020 Elsevier Lt