Effects of different geometric patterns on free form gridshell structures

Gridshells are commonly known as structures with the shape and rigidity of a double curvature shell consisting of a grid, not a continuous surface. In recent decades, these structures have attracted significant attention. The impact of various geometric patterns on free form gridshell structures is investigated here to demonstrate the necessity of collaboration between structural and architectural characteristics in enhancing structure efficiency. To that goal, a framework is proposed where three shells are first designed, and then six geometric patterns are formed on them. The main factors for evaluation of gridshells are decreasing the steel weight as an economic index and decreasing the displacement as a structural index, also, finite element method is used for structurally analyzing the gridshells, and the generated gridshells are compared to each other based on the mentioned indices. For the optimization process, an approach is suggested to find the most optimum gridshell, then numerical results show the efficiency of the proposed alternative approach

Distribution and Antibiotic Resistance Pattern of Bacteria Isolated from Patients with Community-acquired Urinary Tract Infections in Iran: A Cross-sectional Study

Background: Urinary tract infections (UTIs) remain the common infections diagnosed in outpatients as well as hospitalized patients. Multi-drug resistance (MDR) and extensively-drug resistance (XDR) in bacteria is an alarming problem in the world. The aim of this study was to detection of etiologic agents associated with community-acquired urinary tract infections (CA-UTIs) and investigation of antibiotic susceptibility patterns.Methods: This study was performed from September 2014 to March 2015 on outpatients, which referred to Labbafinejad Hospital Clinic, Tehran, Iran. The bacterial pathogenic diversity identified by standard laboratory methods. The antimicrobial resistance rates were performed by Kirby Bauer disc diffusion methods.Results: A total of 303 patients were enrolled in this study, from which 204 (67.3%) were female and 99 (32.5%) were male patients. Escherichia coli was the dominant species (69%), followed by Enterococcus faecalis (12.8%) and Klebsiella pneumoniae (4.6%). High resistance rate to nalidixic acid (73.8%), trimethoprim/Sulfamethoxazole (54.3%), ciprofloxacin (54.3%) in E. coli,  and tetracycline (89.7%) in E. faecalis strains and high susceptibility rate to meropenem (96.6%), imipenem (95.2%), amikacin (90.4%), cefoxtin (87.6%), and  nitrofurantoin (82.8%)  in E. coli,  and nitrofurantoin (100%)                                                                                                                                                                                                                                                                                                                                                                      in E. faecalis strains were observed. In addition, 43.5% of the strains were multidrug-resistant (MDR).Conclusions: This study showed that E. coli was the predominant uropathogen of CA-UTIs in this geographical area. It also demonstrated the empirical treatment of urinary tract infections may be difficult due to high resistance to commonly used antibiotics. Continuous monitoring of MDR organisms and drug resistance patterns are needed to prevent treatment failure and reduce selective pressure. These findings suggest the use of nitrofurantoin, cefoxitin, and amikacin in this area of the country

Distribution and Antibiotic Resistance Pattern of Bacteria Isolated from Patients with Community-acquired Urinary Tract Infections in Iran: A Cross-sectional Study

Background: Urinary tract infections (UTIs) remain the common infections diagnosed in outpatients as well as hospitalized patients. Multi-drug resistance (MDR) and extensively-drug resistance (XDR) in bacteria is an alarming problem in the world. The aim of this study was to detection of etiologic agents associated with community-acquired urinary tract infections (CA-UTIs) and investigation of antibiotic susceptibility patterns.Methods: This study was performed from September 2014 to March 2015 on outpatients, which referred to Labbafinejad Hospital Clinic, Tehran, Iran. The bacterial pathogenic diversity identified by standard laboratory methods. The antimicrobial resistance rates were performed by Kirby Bauer disc diffusion methods.Results: A total of 303 patients were enrolled in this study, from which 204 (67.3%) were female and 99 (32.5%) were male patients. Escherichia coli was the dominant species (69%), followed by Enterococcus faecalis (12.8%) and Klebsiella pneumoniae (4.6%). High resistance rate to nalidixic acid (73.8%), trimethoprim/Sulfamethoxazole (54.3%), ciprofloxacin (54.3%) in E. coli,  and tetracycline (89.7%) in E. faecalis strains and high susceptibility rate to meropenem (96.6%), imipenem (95.2%), amikacin (90.4%), cefoxtin (87.6%), and  nitrofurantoin (82.8%)  in E. coli,  and nitrofurantoin (100%)                                                                                                                                                                                                                                                                                                                                                                      in E. faecalis strains were observed. In addition, 43.5% of the strains were multidrug-resistant (MDR).Conclusions: This study showed that E. coli was the predominant uropathogen of CA-UTIs in this geographical area. It also demonstrated the empirical treatment of urinary tract infections may be difficult due to high resistance to commonly used antibiotics. Continuous monitoring of MDR organisms and drug resistance patterns are needed to prevent treatment failure and reduce selective pressure. These findings suggest the use of nitrofurantoin, cefoxitin, and amikacin in this area of the country

The Effects of Deferoxamine on the Up regulation of Chemokine Receptor 2 in Bone Marrow Stromal Stem Cells

Background: Bone marrow stromal stem cells (BMSCs) are non-hematopoietic, stromal cellsthat can differentiate into mesenchymal and other type of tissues. The BMSCs have properties that make them ideal candidates for tissue engineering. The present study aimed to investigate the effect of deferoxamine (DFO) on homing of bone marrow-derived mesenchymal stem cell, and to examine if DFO can increase migration and subsequent homing of mesenchymal stem cells (MSCs) in vitro.Methods: BMSCs were isolated from the long bones of NMARI rats through density gradientcentrifugation and adherent cell culture. Next, they were treated using DFO in Dulbecco’s modified eagle medium (DMEM) for 24 h. The expression of chemokine receptor 2 (CCR2) were assessed using RT-PCR.Results: BMSCs expressed CCR2 on a large proportion of cells. In DFO-treated BMSCs,expression of CCR2 (P<0.005) significantly increased compared to that in control groups. Elevation and up regulation of CCR2 in DFO-treated MSCs were observed.Conclusion: Preconditioning of BMSCs using DFO prior to transplantation could increasehoming of BMSCs through affecting some chemokine receptors as well as proteases involved and thus improve the efficacy of cell therapy

First detection of efrAB, an ABC multidrug efflux pump in Enterococcus faecalis in Tehran, Iran

Enterococcus faecalis is one of the most significant pathogen in both nosocomial and community-acquired infections. Reduced susceptibility to antibiotics is in part due to efflux pumps. This study was conducted on 80 isolates of E. faecalis isolated from outpatients with urinary tract infection during a period of 1 year from April 2014 to April 2015. The antibiotic susceptibility patterns of isolates were determined by the disk diffusion method and presence of efrA and efrB genes was detected by PCR and sequencing. Minimum inhibitory concentrations (MICs) to ciprofloxacin (CIP) were measured with and without carbonyl cyanide 3-chlorophenylhydrazone (CCCP) by broth microdilution. The highest resistance rate was observed to erythromycin (83.3%) and the prevalence of efrA and efrB genes in all E. faecalis isolates was 100%. This study showed that 9 out of 13 (69.2%) ciprofloxacin-resistant isolates became less resistant at least fourfolds to CIP in the presence of efflux pump inhibitor. Our result showed that CCCP as an efflux inhibitor can increase effect of CIP as an efficient antibiotic and it is suggested that efrAB efflux pumps are involved in resistance to fluoroquinolone

Upplevelsen av hälsorelaterad livskvalité hos individer med hjärtsvikt

ABSTRACT Background: It is estimated that at least 23 million people in the world suffer from heart failure, in Sweden cardiovascular disease is the most common cause of death. Heart failure is a syndrome caused by underlying diseases with severe symptoms. The severe picture of symptoms affects everyday life. Aim: The aim of this study was to investigate which factors affect the quality of life of individuals affected by heart failure and how they experience their quality of life. Method: Literature review was conducted using descriptive design to answer the aim of this study. PubMed and CINAHL have been used as databases for the literature research. The result was based on nine original articles with only qualitative approach and one with mixed methods. The articles were published between 2010-2020. The quality of the articles was then reviewed based on Statens beredning för medicinskt och social utvärderings quality template. Result: The individuals experienced a change in quality of life in connection with the challenges that arose due to heart failure. The condition of the disease led to various factors that affected the quality of life. These factors were; psychological, physical, social and financial, which affected at different levels to a eventual changed quality of life. Conclusion: The result of this literature review shows that the experience of quality of life in relation to heart failure was largely influenced and impaired. What has been perceived as affecting individuals' quality of life are overall factors such as; psychological, physical, social and financial needs. For this reason, it is of great importance that the nurse gain an increased understanding and knowledge of this patient group to optimize the well-being and quality of life for the individuals.   Keywords: Quality of life, heart failure, experiences

Upplevelsen av hälsorelaterad livskvalité hos individer med hjärtsvikt

ABSTRACT Background: It is estimated that at least 23 million people in the world suffer from heart failure, in Sweden cardiovascular disease is the most common cause of death. Heart failure is a syndrome caused by underlying diseases with severe symptoms. The severe picture of symptoms affects everyday life. Aim: The aim of this study was to investigate which factors affect the quality of life of individuals affected by heart failure and how they experience their quality of life. Method: Literature review was conducted using descriptive design to answer the aim of this study. PubMed and CINAHL have been used as databases for the literature research. The result was based on nine original articles with only qualitative approach and one with mixed methods. The articles were published between 2010-2020. The quality of the articles was then reviewed based on Statens beredning för medicinskt och social utvärderings quality template. Result: The individuals experienced a change in quality of life in connection with the challenges that arose due to heart failure. The condition of the disease led to various factors that affected the quality of life. These factors were; psychological, physical, social and financial, which affected at different levels to a eventual changed quality of life. Conclusion: The result of this literature review shows that the experience of quality of life in relation to heart failure was largely influenced and impaired. What has been perceived as affecting individuals' quality of life are overall factors such as; psychological, physical, social and financial needs. For this reason, it is of great importance that the nurse gain an increased understanding and knowledge of this patient group to optimize the well-being and quality of life for the individuals.   Keywords: Quality of life, heart failure, experiences

Computational analysis of thrombosis risk with variations in left ventricular assist device inflow cannula design in a multi-patient model

Background and Objectives: Left ventricular assist devices (LVADs) are mechanical pumps used to support patients with end-stage heart failure. The inflow cannula is a critical component of the LVAD as it connects the pump to the left ventricle, allowing blood to be drawn from the heart. However, the design of the cannula can significantly impact LV hemodynamics and cause complications, including thrombosis. Therefore, this study aimed to analyze the numerical effects of left ventricle (LV) size on cannula design in order to enhance hemodynamic performance using post-operative left ventricular assist device (LVAD) models. Methods: A parametric design evaluation of two different inflow cannulas were carried out on left ventricles (LV) of varying sizes (ranging from 154 to 430 ml) constructed from computerized tomography (CT) data from VAD patients using computational fluid dynamics (CFD) simulations. The study analyzed three key factors contributing to thrombosis formation: blood residence time, blood stagnation ratio, and wall shear stress. Results: Results showed higher blood residence time and stagnation ratio for larger left ventricular sizes. In addition, increasing the insertion length of the cannula reduced the average wall shear stress. Conclusion: Overall, the study's findings suggest that the optimal cannula shape for LVADs varies with left ventricular size.</p

The impact of small movements with dual lumen cannulae during venovenous extracorporeal membrane oxygenation: A computational fluid dynamics analysis

Venovenous Extracorporeal Membrane Oxygenation (VV ECMO) provides respiratory support to patients with severe lung disease failing conventional medical therapy. An essential component of the ECMO circuit are the cannulas, which drain and return blood into the body. Despite being anchored to the patient to prevent accidental removal, minor cannula movements are common during ECMO. The clinical and haemodynamic consequences of these small movements are currently unclear. This study investigated the risk of thrombosis and recirculation caused by small movements of a dual lumen cannula (DLC) in an adult using computational fluid dynamics. Methods: The 3D model of an AVALON Elite DLC (27 Fr) and a patient-specific vena cava and right atrium were generated for an adult patient on ECMO. The baseline cannula position was generated where the return jet enters the tricuspid valve. Alternative cannula positions were obtained by shifting the cannula 5 and 15 mm towards inferior (IVC) and superior (SVC) vena cava, respectively. ECMO settings of 4 L/min blood flow and pulsatile flow at SVC and IVC were applied. Recirculation was defined as a scalar value indicating the infused oxygenated blood inside the drainage lumen, while thrombosis risk was evaluated by shear stress, stagnation volume, washout, and turbulent kinetic energy. Results: Recirculation for all models was less than 3.1 %. DLC movements between -5 to 15 mm increased shear stress and turbulence kinetic energy up to 24.7 % and 11.8 %, respectively, compared to the baseline cannula position leading to a higher predicted thrombosis risk. All models obtained a complete washout after nine seconds except for when the cannula migrated 15 mm into the SVC, indicating persisting stasis and circulating zones. Conclusion: In conclusion, small DLC movements were not associated with an increased risk of recirculation. However, they may increase the risk of thrombosis due to increased shear rate, turbulence, and slower washout of blood. Developing effective cannula securement devices may reduce this risk.</p