44 research outputs found
Ефективність праці на вугільних шахтах:
Наведено основні положення з теорії та методології ефективності праці, обґрунтовано показники для оцінки її окремих сторін і загального рівня на підприємстві. Розглянуто фактори й закономірності їхнього впливу на ефективність праці та виявлені оптимальні параметри найбільш впливових факторів.
Викладено основні положення методики виявлення та реалізації резервів підвищення ефективності праці на вуглевидобувних підприємствах. Показано прийоми вибору оптимального варіанта інновацій в галузі підвищення ефективності праці на вугільній шахті за допомогою ПЕОМ і дано відповідне програмне забезпечення. Основні положення методики проілюстровано комплексним прикладом проведення цієї роботи в умовах конкретної шахти.
Призначено для широкого кола спеціалістів економічних служб вугільних підприємств, співробітників науково-дослідних підрозділів і організацій, проектних інститутів, що займаються розробкою проектів організації виробництва та праці. Може бути використана при вивченні окремих питань економіки, організації праці та виробництва студентами гірничих вузів а також в системі підвищення кваліфікації
Effects of predisposing, reinforcing and enabling factors on self-care behaviors of the patients with diabetes mellitus in the Minoodasht city, Iran
Background: To control diabetes mellitus (DM) it is necessary to make overall changes in the life style of the patients. The aim of this study was to determine the effects of predisposing, reinforcing and enabling factors on self-care behaviors of the patients with DM in the Minoodasht city, Iran in 2012.Methods: In this quasi-experimental study, 78 people with DM were selected by convenience sampling method. In the first stage of study, the educational program was compiled and executed on six information sessions. To present the informative content, a video projector and different lecturing methods including questions and answers, dynamic group discussion and different educational materials such as pamphlets and CDs were employed. After one month, the efficiency of the educational program was determined by using the same questioner. Data were analyzed using paired sample T-test and McNemar test. Results: The mean age of participants was 49 (SD: 3.27.) years old, 87.2 were married, and 19.2 were illiterate. The results showed that the enabling factors like adopting to go on a diet and the educational classes facilitated by the staff had significant effects on health care behavior of the patients. Furthermore 69.2 of the participants adopted to go on a diet before the educational sessions; that figure increased to 94.9 after the educational sessions. According to the results the mean scores for the knowledge, attitude, and behavior, reinforcement factors and enabling factors increased significantly after of the educational intervention (p- value >0.001).Conclusion: Predisposing, enabling and reinforcement factors affected in taking self-care behavior in the patient with DM. © 2015 Borhani et al.; licensee BioMed Central
Reduction–oxidation (redox) system in radiation-induced normal tissue injury: molecular mechanisms and implications in radiation therapeutics
Every year, millions of cancer patients undergo radiation therapy for treating and destroying abnormal cell growths within normal cell environmental conditions. Thus, ionizing radiation can have positive therapeutic effects on cancer cells as well as post-detrimental effects on surrounding normal tissues. Previous studies in the past years have proposed that the reduction and oxidation metabolism in cells changes in response to ionizing radiation and has a key role in radiation toxicity to normal tissue. Free radicals generated from ionizing radiation result in upregulation of cyclooxygenases (COXs), nitric oxide synthase (NOSs), lipoxygenases (LOXs) as well as nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase), and their effected changes in mitochondrial functions are markedly noticeable. Each of these enzymes is diversely expressed in multiple cells, tissues and organs in a specific manner. Overproduction of reactive oxygen radicals (ROS), reactive hydroxyl radical (ROH) and reactive nitrogen radicals (RNS) in multiple cellular environments in the affected nucleus, cell membranes, cytosol and mitochondria, and other organelles, can specifically affect the sensitive and modifying enzymes of the redox system and repair proteins that play a pivotal role in both early and late effects of radiation. In recent years, ionizing radiation has been known to affect the redox functions and metabolism of NADPH oxidases (NOXs) as well as having destabilizing and detrimental effects on directly and indirectly affected cells, tissues and organs. More noteworthy, chronic free radical production may continue for years, increasing the risk of carcinogenesis and other oxidative stress-driven degenerative diseases as well as pathologies, in addition to late effect complications of organ fibrosis. Hence, knowledge about the mechanisms of chronic oxidative damage and injury in affected cells, tissues and organs following exposure to ionizing radiation may help in the development of treatment and management strategies of complications associated with radiotherapy (RT) or radiation accident victims. Thus, this medically relevant phenomenon may lead to the discovery of potential antioxidants and inhibitors with promising results in targeting and modulating the ROS/NO-sensitive enzymes in irradiated tissues and organ injury systems
Melatonin Attenuates Upregulation of Duox1 and Duox2 and Protects against Lung Injury following Chest Irradiation in Rats
Objective: The Lung is one of the most radiosensitive organs of the body. The infiltration of macrophages and lymphocytes into the lung is mediated via the stimulation of T-helper 2 cytokines such as IL-4 and IL-13, which play a key role in the development of fibrosis. It is likely that these cytokines induce chronic oxidative damage and inflammation through the upregulation of Duox1 and Duox2, which can increase the risk of late effects of ionizing radiation (IR) such as fibrosis and carcinogenesis. In the present study, we aimed to evaluate the possible increase of IL-4 and IL-13 levels, as well as their downstream genes such as IL4ra1, IL13ra2, Duox1, and Duox2. Materials and Methods: In this experimental animal study, male rats were divided into 4 groups: i. Control, ii. Melatonin-treated, iii. Radiation, and iv. Melatonin (100 mg/kg) plus radiation. Rats were irradiated with 15 Gy 60Co gamma rays and then sacrificed after 67 days. The expressions of IL4ra1, IL13ra2, Duox1, and Duox2, as well as the levels of IL-4 and IL-13, were evaluated. The histopathological changes such as the infiltration of inflammatory cells, edema, and fibrosis were also examined. Moreover, the protective effect of melatonin on these parameters was also determined. Results: Results showed a 1.5-fold increase in the level of IL-4, a 5-fold increase in the expression of IL4ra1, and a 3-fold increase in the expressions of Duox1 and Duox2. However, results showed no change for IL-13 and no detectable expression of IL13ra2. This was associated with increased infiltration of macrophages, lymphocytes, and mast cells. Melatonin treatment before irradiation completely reversed these changes. Conclusion: This study has shown the upregulation of IL-4-IL4ra1-Duox2 signaling pathway following lung irradiation. It is possible that melatonin protects against IR-induced lung injury via the downregulation of this pathway and attenuation of inflammatory cells infiltration. © 2019 Royan Institute (ACECR). All rights reserved
Targeting of inflammation for radiation protection and mitigation
Background: Inflammation is the response of the immune system that guards the body against several harmful stimuli in normal conditions. However, in response to ionizing radiation that leads to a massive cell death and DNA aberrations, this phenomenon causes various side effects in normal tissues. Inflammation is involved in various side effects such as gastrointestinal toxicity, mucositis, skin reactions, nervous system damage, pneumonitis, fibrosis and so on. Discussion: Observations have proposed that inflammatory mediators are involved in the toxic effect of ionizing radiation on non-irradiated cells via a phenomenon named bystander effect. Inflammation in both irradiated and non-irradiated cells can trigger genomic instability, leading to increased risk of carcinogenesis. Targeting the inflammatory mediators has been an interesting idea for improving the therapeutic ratio throughout the reduction of normal tissue injury as well as an increase in tumor response to radiotherapy. Conclusion: So far, various targets have been proposed for the amelioration of radiation toxicity in radiotherapy. Of different targets, NF-κB, COX-2, some of NADPH Oxidase subfamilies, TGF-β, p38 and the renin-angiotensin system have shown promising results. Interestingly, inhibition of these targets can help sensitize the tumor cells to the radiation treatment with some mechanisms such as suppression of angiogenesis and tumor growth as well as induction of apoptosis. In this review, we focus on recent advances on promising studies for targeting the inflammatory mediators in radiotherapy. © 2018 Bentham Science Publishers
COX-2 in radiotherapy: A potential target for radioprotection and radiosensitization
Background: Each year, millions of people die from cancer. Radiotherapy is one of the main treatment strategies for cancer patients. Despite the beneficial roles of treatment with radiation, several side effects may threaten normal tissues of patients in the years after treatment. Discussion: Moreover, high incidences of second primary cancers may reduce therapeutic ratio of radiotherapy. The search for appropriate targets of radiosensitization of tumor cells as well as radioprotection of normal tissues is one of the most interesting aims in radiobiology. Cyclooxygenase-2 (COX-2), as an inflammatory mediator has attracted interests for both aims. COX-2 activity is associated with ROS production and inflammatory signs in normal tissues. These effects further amplify radiation toxicity in irradiated cells as well as adjacent cells through a phenomenon known as Bystander effect. Increased COX-2 expression in distant non-irradiated tissues causes oxidative DNA damage and elevated cancer risk. Moreover, in tumors, the activation of this enzyme can increase resistance of malignant cells to radiotherapy. Hence, the inhibition of COX-2 has been proposed for better therapeutic response and amelioration of normal tissues. Celecoxib is one of the most studied COX-2 inhibitor for radiosensitization and radioprotection, while some other inhibitors have shown interesting results. Conclusion: In this review, we describe the role of COX-2 in radiation normal tissue injury as well as irradiated bystander and non-targeted cells. In addition, mechanisms of COX-2 induced tumor resistance to radiotherapy and the potential role of COX-2 inhibition are discussed. © 2018 Bentham Science Publishers
Generalized or abdominal obesity: Which one better identifies cardiometabolic risk factors among children and adolescents? The CASPIAN III study
Objectives: We investigated the association of generalized and abdominal obesity with cardiometabolic risk factors in children and adolescents. Methods: Data were obtained from a surveillance system entitled CASPIAN-III study in school students aged 10-18 years in Iran. Data of subjects with normal body mass index (BMI) or above (BMI≥5th percentile) were analyzed. The associations of obesity with cardiometabolic risk factors were tested using logistic regression models. Results: In the sample of 4641 children and adolescents, overweight/obese children were more likely to have metabolic syndrome and cardiometabolic risk factors compared with their normal weight counterparts. Among these parameters, elevated TG had the strongest association with degree of obesity (overweight: OR1/42.28 95% CI 1.59-3.26; obesity: OR1/45.63 95% CI 4.27,7.43). Combined generalized and abdominal obesity increased the risk of high blood pressure, elevated triglyceride and total cholesterol. Conclusions: Combined type of generalized and abdominal obesity is a predictor of cardiometabolic risk factors. © The Author 2014
Stem Cell Tracing Through MR Molecular Imaging
Abstract
Stem cell therapy opens a new window in medicine to overcome several diseases that remain incurable. It appears such diseases as cardiovascular disorders, brain injury, multiple sclerosis, urinary system diseases, cartilage lesions and diabetes are curable with stem cell transplantation. However, some questions related to stem cell therapy have remained unanswered. Stem cell imaging allows approval of appropriated strategies such as selection of the type and dose of stem cell, and also mode of cell delivery before being tested in clinical trials. MRI as a non-invasive imaging modality provides proper conditions for this aim. So far, different contrast agents such as superparamagnetic or paramagnetic nanoparticles, ultrasmall superparamagnetic nanoparticles, fluorine, gadolinium and some types of reporter genes have been used for imaging of stem cells. The core subject of these studies is to investigate the survival and differentiation of stem cells, contrast agent’s toxicity and long term following of transplanted cells. The promising results of in vivo and some clinical trial studies may raise hope for clinical stem cells imaging with MRI.
Keywords: Stem cell, MRI, Molecular imaging, Regenerative medicine, Cell therap
Metformin protects against radiation-induced heart injury and attenuates the upregulation of dual oxidase genes following Rat's chest irradiation
Radiation-induced heart toxicity is one of the serious side effects after a radiation disaster or radiotherapy for patients with chest cancers, leading to a reduction in the quality of life of the patients. Evidence has shown that infiltration of inflammatory cells plays a key role in the development of functional damages to the heart via chronic upregulation of some pro-fibrotic and pro-inflammatory cytokines. These changes are associated with continuous free radical production and increased stiffness of heart muscle. IL-4 and IL-13 are two important pro-fibrotic cytokines which contribute to the side effects of ionizing radiation exposure. Recent studies have proposed that IL-4 through upregulation of DUOX2, and IL-13 via stimulation of DUOX1 gene expression, are involved in the development of radiation late effects. In the present study, we aimed to detect changes in the expression of these pathways following irradiation of rat's heart. Furthermore, we evaluated the possible protective effect of metformin on the development of these abnormal changes. 20 male rats were divided into 4 groups (control, radiation, metformin treated, metformin + radiation). These rats were irradiated with 15 Gy 60 Co gamma rays, and sacrificed after 10 weeks for evaluation of the changes in the expression of IL4R1, IL-13R2a, DUOX1 and DUOX2. In addition, the levels of IL-4 and IL-13 cytokines, as well as infiltration of macrophages and lymphocytes were detected. Results showed an upregulation of both DUOX1 and DUOX2 pathways in the presence of metformin, while the level of IL-13 did not show any significant change. This was associated with infiltration of macrophages and lymphocytes. Also, treatment with metformin could significantly attenuate accumulation of inflammatory cells, and upregulate these pathways. Therefore, suppression of dual oxidase genes by metformin may be a contributory factor to its protective effect. © 2018, Babol University of Medical Sciences
Reduction�oxidation (redox) system in radiation-induced normal tissue injury: molecular mechanisms and implications in radiation therapeutics
Abstract
Every year, millions of cancer patients undergo radiation therapy for treating and destroying abnormal cell growths within normal cell environmental conditions. Thus, ionizing radiation can have positive therapeutic effects on cancer cells as well as post-detrimental effects on surrounding normal tissues. Previous studies in the past years have proposed that the reduction and oxidation metabolism in cells changes in response to ionizing radiation and has a key role in radiation toxicity to normal tissue. Free radicals generated from ionizing radiation result in upregulation of cyclooxygenases (COXs), nitric oxide synthase (NOSs), lipoxygenases (LOXs) as well as nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase), and their effected changes in mitochondrial functions are markedly noticeable. Each of these enzymes is diversely expressed in multiple cells, tissues and organs in a specific manner. Overproduction of reactive oxygen radicals (ROS), reactive hydroxyl radical (ROH) and reactive nitrogen radicals (RNS) in multiple cellular environments in the affected nucleus, cell membranes, cytosol and mitochondria, and other organelles, can specifically affect the sensitive and modifying enzymes of the redox system and repair proteins that play a pivotal role in both early and late effects of radiation. In recent years, ionizing radiation has been known to affect the redox functions and metabolism of NADPH oxidases (NOXs) as well as having destabilizing and detrimental effects on directly and indirectly affected cells, tissues and organs. More noteworthy, chronic free radical production may continue for years, increasing the risk of carcinogenesis and other oxidative stress-driven degenerative diseases as well as pathologies, in addition to late effect complications of organ fibrosis. Hence, knowledge about the mechanisms of chronic oxidative damage and injury in affected cells, tissues and organs following exposure to ionizing radiation may help in the development of treatment and management strategies of complications associated with radiotherapy (RT) or radiation accident victims. Thus, this medically relevant phenomenon may lead to the discovery of potential antioxidants and inhibitors with promising results in targeting and modulating the ROS/NO-sensitive enzymes in irradiated tissues and organ injury systems.
Keywords
Radiation Redox Normal tissue injury Inflammation NADPH oxidas