Investigating effective factors on estimated hemorrhage intraoperative in brain meningioma surgery

Introduction: The primary and definitive diagnosis of meningioma is based on histological assessment; however, employing imaging methods, like Magnetic Resonance Imaging (MRI) is very helpful to describe lesion's characteristics. Accordingly, we decided to study the effect of imaging factors, like MRI data on the volume of hemorrhage (estimated blood loss) during meningioma surgery. Methods: This was a cross-sectional, retrospective, and analytical study. The eligible patients were those with meningioma who were candidates for surgery. A total of 40 patients with meningioma were selected and assessed. The preoperative imaging findings were recorded, then estimated blood loss during the surgery was determined Results: A reverse association was revealed between the degree of proximity to the nearest sinus and the rate of bleeding. Furthermore, the size of the mass was positively associated with the rate of bleeding; however, there was no significant correlation between the volume of bleeding and other parameters, including the degree of edema, the volume of mass, the site of the tumor in the brain, and the histological subtype of the tumor. The mean time of operation was strongly correlated with blood loss. The rate of bleeding was more expected in hypertensive versus normotensive patients. Conclusion: Bleeding in various volumes could be a frequent finding in intracranial meningioma surgery. Overall, tumor size, the duration of surgery, a history of hypertension, and distance to the nearest sinuses were the main determinants for the severity of hemorrhage in patients undergoing meningioma surgery. © 2020 Iran University of Medical Sciences. All rights reserved

Designing two models for comprehensive center of excellence and center of excellence in the field of medical sciences in Iran

Background: Despite exist several centers of excellence in the various medical field in the country, most of them lack a single procedure and organizational structures in their functioning, organizing, targeting, etc. So the study aimed to design an organizational model that meets the goals and mission of them in the field of medical sciences. Methods: This qualitative and applied research was conducted in two comparative and analytical stages from May 2016 to February 2017 in Iran. The location of the study includes a university, research institute, health center, or research center known as a center of excellence. In the analytical stage, 10 experts and managers of the top centers were selected through a targeted sampling method as a study sample. In the comparative section, all 50 centers of excellence and similar specimens in the world were selected. The data collection tool was a semi-structured interview in the analytical section and the ministry of health's documents. In comparative section data, bases and official sites of the centers were analyzed. Results: The term "center of excellence" for units that play a role in one or two of the three dimensions of education, research, and treatment, and the term "comprehensive center of excellence" for a unit that plays a role in all three dimensions, in addition to knowledge management have been agreed upon. Seven missions (national and international) for the comprehensive center of excellence and five different missions for center of excellence were formulated. The role of the ministry of health in the guidance of these centers was agreed in the seven items. Ultimately, the macro model of organizing "comprehensive centers of excellence" and "centers of excellence" at the university level and ministry of health level was designed and presented. Conclusion: Correcting the governance structure of these centers in ministry, unit command at the highest level of management by reorganizing of duties, the authority of High Council for the Center of Excellences and the establishment of a systematic relationship between ministry and vices are the part of the requirements for fulfilling the roles and mission of center of excellence. © 2020 Tehran University of Medical Sciences. All rights reserved

Effect of rapid solidification on the microstructure and microhardness of BS1452 grade 250 hypoeutectic grey cast iron

Containerless solidification of low alloyed commercial grey cast iron in two different cooling media (N2 and He) using a 6.5 m high vacuum drop-tube have been investigated. Both the conventionally cooled, as-cast alloy and the rapidly cooled drop-tube samples were characterized using SEM, XRD and Vickers microhardness apparatus. The estimated range of cooling rates are 200 K s−1 to 16,000 K s−1 for N2 cooled droplets and 700 K s−1 to 80,000 K s−1 for He cooled droplets (in each case for 850 μm and 38 μm diameter droplets respectively). Microstructural analysis reveals that the as-received bulk sample displayed a graphitic structure while the rapidly cooled samples display decreasing amounts of α-Fe as the cooling rate increases. At moderate cooling rates α is replaced with γ and Fe3C, while at higher cooling rates with α′. Microhardness increase with cooling rate but cannot be mapped uniquely onto cooling rate, suggesting undercooling also influences the mechanical properties

Epidemiological characteristics of coronavirus disease 2019 (COVID-19) patients in IRAN: A single center study

Background: An outbreak of COVID-19 in Iran has spread throughout the country. Identifying the epidemiological characteristics of this disease will help to make appropriate decisions and thus control the epidemic. The aim of this study was characterization of the epidemiological features of COVID-19 in Iran. Methods: In this retrospective study, data related to the epidemiological characteristics of COVID-19 patients admitted to Baqiyatallah Hospital in Tehran, Iran, from 19 February 2020 to 15 April 2020 have been analyzed and reported. Patient characteristics including age, gender and underlying diseases were investigated. Data were collected through patient records. Sex ratio, Case Fatality Rate (CFR) and daily trend of cases were also determined. A multiple logistic regression analysis was also performed to assess affecting factors on mortality. Results: From February 19, 2020 to April 15, 2020, 12870 patients referred to the hospital emergency department, of which 2968 were hospitalized with COVID-19 diagnosis. The majority of cases were in the age group of 50 to 60 years of old. The male-to-female ratio was 1.93:1. A total of 239 deaths occurred among all cases for an overall CFR of 1.85 based on the total number of patients (both outpatient and inpatient) and 8.06 among hospitalized patients. Out of all patients 10.89 had comorbidity. Diabetes, chronic respiratory diseases, hypertension, cardiovascular diseases, chronic Kidney diseases and cancer were the most common comorbidities with 3.81, 2.02, 1.99, 1.25, 0.60 and 0.57 , respectively. Male gender (OR=1.45, 95 CI: 1.08-1.96), older age (OR=1.05, 95 CI: 1.04-1.06) and having underlying diseases (OR=1.53, 95 CI: 1.04-2.24) were significantly associated with mortality. Conclusions: The results of this study showed that Male gender, older age and having comorbidities were significantly associated with the risk of death among COVID-19 patients. It is important to pay special attention to male elderly patients with underlying diseases. © 2020 Elsevier B.V

Effect of Shielding Gas Composition on Geometry and Austenite Formation in Low Power Pulsed Nd:YAG Laser Welded 2205 Duplex Stainless Steel

This paper presents an investigation into effect of nitrogen content of shielding gas mixture on weld geometry, microstructure and hardness of pulsed laser welded 2205 duplex stainless steel. Full penetration autogenous welding was performed on 2 mm thick plates using a low power pulsed Nd: YAG laser. light and scanning electron microscopy were used to study the resulting microstructures. It is observed that 2 mm full penetrated joint decreases to 1.8 mm by dominating nitrogen in argon-nitrogen mixture. Different morphologies of austenite phase as well as an increase of 8% of its content can be observed in pure nitrogen shielded welds. Average weld grain size in sample which is welded in nitrogen atmosphere stands at approximately 41 μm which is smallerthan that of argon atmosphere which is about 51 μm. Micro-hardness test reveals that hardness values increase from 280 HV in base metal to 307 HV in weld center line and the shielding gas mixture does not significantly influence the weld hardness

The effects of a single session aerobic exercise on obestatin gene expression in trained women

"nBackground: Studies indicate that obestatin, an anti-hunger peptide, plays an important role in energy balance, GH secretion, and body weight. It has been physiologically shown that obestatin apposes the function of Ghrelin. The purpose of the present study was to investigate the effects of a single session of aerobic exercise in trained women (a 1.5-mile run) on the expression of obestatin gene found in lymphocytes."n "nMethods: 16 trained female participants (4±1 years of training experience) were voluntarily selected from Khorasan province in Iran and were randomly divided into two groups: the control and aerobic exercise groups. The participants in the aerobic group were asked to run for 1.5 miles with a fixed speed (70 VO2 max) while the controls were passively present in the exercise environment. Following an overnight fast, blood samples (10 ml from the antecubital vein) were collected before and immediately after the exercise from all the participants. Obestatin expression was investigated after separating the lymphocytes by centrifuge and using semi-quantitative RT-PCR."n "nResults: There was a rise in obestatin gene expression in the case group after one session of aerobic training versus the control group but the changes were not statistically significant."n "nConclusion: The results indicated that a single aerobic exercise could not significantly increase the expression of obestatin. Perhaps the type, duration and intensity of the applied protocol in this study did not have a cumulative effect on this gene although these results are in harmony with the results of other studies in this regard

A report of three cases of anesthesia in patients undergoing simultaneous kidney-pancreas transplantation

BACKGROUND AND OBJECTIVE: Induction of anesthesia and surgery lead to metabolic changes and make it difficult for diabetic patients to control their blood sugar. Complications of kidney failure may also affect the management of anesthesia in these people. The present study was conducted to report three cases of anesthesia in patients undergoing simultaneous kidney-pancreas transplantation. CASE REPORTS: The first patient was a 33-year-old woman, the second patient was a 28-year-old woman, and the third patient was a 27-year-old woman, all of whom had diabetes mellitus and diabetic nephropathy and were under hemodialysis treatment. All patients underwent general anesthesia. Drugs used for anesthesia included midazolam, fentanyl, cisatracurium, and propofol. All patients underwent simultaneous kidney-pancreas transplantation. Postoperative condition of transplanted patients was favorable and they are still under the supervision of a physician. CONCLUSION: Based on the results of this study, good management of anesthesia and the use of appropriate anesthetic drugs and control of hemodynamic conditions and pain management can improve the outcome of kidney-pancreas transplantation