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1.
Sci Rep ; 12(1): 16600, 2022 Oct 05.
Article in English | MEDLINE | ID: mdl-36198755

ABSTRACT

In the present paper, the interrelated aspects of additive manufacturing-microstructure-property in directed energy deposition of SS316L-IN718 multi-material were studied through numerical modeling and experimental evaluation. The printability concept and solidification principles were used for this purpose. The printability analysis showed that the SS316L section is more susceptible to composition change and lack of fusion, respectively due to the high equilibrium vapor pressure of manganese and the more efficient heat loss in the initial layers. However, the IN718 section is more prone to distortion due to the formation of a larger melt pool, with a maximum thermal strain of 3.95 × 10-3 in the last layer. As the process continues, due to heat accumulation and extension of the melt pool, the cooling rate decreases and the undercooling level increases, which respectively result in coarser microstructure and more instability of solidification front in the build direction, as also observed in the experimental results. The difference is that the dendritic microstructure of the IN718 section, due to the eutectic reaction L → γ + Laves, is formed on a smaller scale compared to the cellular microstructure of the SS316L section. Also, the decrease in cooling rate caused the secondary phase fraction in each section (delta ferrite in SS316L and Laves in IN718) to increase almost linearly. However, the hardness calculation and measurement showed similarly, even though with the transition from SS316L to IN718 the hardness is significantly increased due to higher yield strength of the matrix and the presence of Laves intermetallic phase (~ 260 HV0.3), the hardness in each section decreases slightly due to the coarsening of the microstructure from the initial layer to the final.

2.
Biomed Res Int ; 2021: 2295920, 2021.
Article in English | MEDLINE | ID: mdl-34676259

ABSTRACT

The COVID-19 epidemic is spreading day by day. Early diagnosis of this disease is essential to provide effective preventive and therapeutic measures. This process can be used by a computer-aided methodology to improve accuracy. In this study, a new and optimal method has been utilized for the diagnosis of COVID-19. Here, a method based on fuzzy C-ordered means (FCOM) along with an improved version of the enhanced capsule network (ECN) has been proposed for this purpose. The proposed ECN method is improved based on mayfly optimization (MFO) algorithm. The suggested technique is then implemented on the chest X-ray COVID-19 images from publicly available datasets. Simulation results are assessed by considering a comparison with some state-of-the-art methods, including FOMPA, MID, and 4S-DT. The results show that the proposed method with 97.08% accuracy and 97.29% precision provides the highest accuracy and reliability compared with the other studied methods. Moreover, the results show that the proposed method with a 97.1% sensitivity rate has the highest ratio. And finally, the proposed method with a 97.47% F1-score rate gives the uppermost value compared to the others.


Subject(s)
Algorithms , COVID-19/diagnostic imaging , Diagnosis, Computer-Assisted/methods , Databases, Factual , Humans , Image Enhancement , Machine Learning , Neural Networks, Computer , Radiography/methods , Sensitivity and Specificity , X-Rays
3.
J Tehran Heart Cent ; 14(1): 1-5, 2019 Jan.
Article in English | MEDLINE | ID: mdl-31210763

ABSTRACT

Background: Cardiovascular events are the leading cause of mortality and are highly associated with lifestyle. We aimed to evaluate the prevalence of coronary artery disease (CAD) and its major risk factors in the western Iranian city of Borujerd. Methods: This cross-sectional study was conducted on 801 subjects older than 35 years of age, recruited via cluster sampling in Borujerd. The diagnosis of CAD was based on the positive results of Rose Angina Questionnaire, Minnesota coding, or prior history of CAD. Then, the risk factors were measured by biochemistry and relevant laboratory examinations, or data extraction from the subjects' history. Results: The study sample consisted of 412 men and 389 women at a mean age of 54.82±12.11 years. The prevalence of risk factors including hypertension, diabetes mellitus, dyslipidemia, smoking, and obesity was 38.2%, 17.4%, 64%, 23.2%, and 22.8%, respectively. Based on the criteria, 19.1% and 31.7% of the CAD cases were definite and probable, respectively. Furthermore, 12.5% had definite signs and symptoms of CAD, and 5.4% had positive Rose Angina Questionnaire outcomes. Conclusion: The current study demonstrated the distribution of CAD in the Iranian city of Borujerd and it was demonstrated that obesity and smoking are the most common risk factors, respectively.

4.
Cardiorenal Med ; 8(3): 217-227, 2018.
Article in English | MEDLINE | ID: mdl-29909417

ABSTRACT

BACKGROUND: Finding patients at risk of developing contrast-induced acute kidney injury (CI-AKI) is important because of its associated complications. In the present study, the contribution of different variables, such as the presence of metabolic syndrome (MetS), the volume creatinine clearance (V/CrCl) ratio, the iodine-dose (I-dose)/CrCl ratio, or hypertension, to CI-AKI was evaluated. METHODS: A total of 255 patients undergoing elective coronary angiography with or without intervention were enrolled and divided into a MetS and a control group. All patients were assessed for the development of CI-AKI after the procedures. RESULTS: CI-AKI occurred in 39.23% (51 of 130) of the MetS patients and 14.4% (18 of 125) of the control group (p < 0.001). The multivariable regression model showed that male sex and the use of statins decreased the risk of CI-AKI, and high triglyceride levels, I-dose/CrCl > 0.52, MetS, CrCl ≤60 mL/min, and age ≥70 years increased the risk of CI-AKI, independent of confounding factors. The difference in the mean V/CrCl ratio was statistically significant between patients who developed CI-AKI and those who did not show renal impairment (2.36 ± 1.35 vs. 1.43 ± 0.89, respectively; p < 0.001). The ROC curve analysis of I-dose/CrCl determined the best cutoff value for patients with and those without MetS as 0.51 and 0.63, with a sensitivity value of 68 and 72% and a specificity value of 73 and 74%, respectively. CONCLUSIONS: We showed that MetS is a strong risk factor for CI-AKI in nondiabetic patients undergoing elective coronary interventions; and the I-dose/CrCl ratio is a strong predictor of CI-AKI in these patients. We suggest that clinicians identify MetS patients and calculate their I-dose/CrCl ratio before coronary interventions.


Subject(s)
Acute Kidney Injury/chemically induced , Contrast Media/administration & dosage , Contrast Media/adverse effects , Creatinine/blood , Iodine/administration & dosage , Iodine/adverse effects , Metabolic Syndrome/complications , Aged , Coronary Angiography/adverse effects , Creatine/blood , Creatine/pharmacokinetics , Female , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Hypertension/complications , Iodine/blood , Male , Metabolic Clearance Rate , Middle Aged , Prospective Studies , ROC Curve , Risk Factors
5.
Stud Health Technol Inform ; 247: 306-310, 2018.
Article in English | MEDLINE | ID: mdl-29677972

ABSTRACT

INTRODUCTION: Ischemic heart disease and stroke have been considered as the first global leading cause of death in last decades [1]. Blood pressure (BP) management is one of the easiest ways suggested for preventing and controlling cardiovascular diseases before the patient develops complications and death-following outcomes. Appearance of technology advancements in the health system has motivated researchers and health providers to study its different aspects and applications in order to improve disease prevention and management. Following these efforts, mobile health (mHealth) technologies were presented to provide people with fast and easier-to-use services. Although there are some unsolved challenges, these technologies have become popular among many people. As an important part of mHealth, mobile applications (apps) have been the focused subject of many studies in the last decade. The objective of this systematic review is to assess the potential effects of mobile apps designed for BP management by scrutinizing the related studies. MATERIALS AND METHODS: Search methods: We searched the following electronic databases in December 2016: Medline (PubMed), National Center for Biotechnology Information (NCBI), Cochrane Central Register of Controlled Trials (CENTRAL), PsycINFO, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Education Resources Information Center(ERIC), Web of Science, ProQuest, and Google Scholar. No language restriction and start point limitation were imposed. SELECTION CRITERIA: We included studies that evaluated and assessed mobile apps for BP management and related clinical trials that considered mobile app as the only difference between intervention and control groups. DATA COLLECTION AND ANALYSIS: Two review authors applied the eligibility criteria, extracted data and assessed the quality of included studies. RESULTS: Literature search resulted in 13 included studies and 27 reviews. 12 records of 13 included studies identified as interventional studies. The review showed that the mobile apps may improve individual's BP condition and medication adherence. CONCLUSION: Most of the studies had emphasized positive effects of mobile apps in BP management. However, there is a necessity for performing further investigations due to the identified issues in this study such as low number of participants and limited intervention period in randomized controlled trials, and interventions limited to only hypertensive or high-risked individual.


Subject(s)
Blood Pressure Monitors , Hypertension/drug therapy , Mobile Applications , Cell Phone , Humans , Medication Adherence , Randomized Controlled Trials as Topic , Telemedicine
6.
J Tehran Heart Cent ; 12(2): 82-84, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28828023

ABSTRACT

Transradial coronary angiography has been known as an alternative to the transfemoral approach with fewer serious complications. Radial artery pseudoaneurysms present as a rare complication of transradial catheterization. Although some methods have been applied for the obliteration of pseudoaneurysms, the use of radial bands such as the TR Band® (Terumo Medical Corporation, Somerset, NJ) is a novel efficient technique only suggested by a few reports. We describe a 34-year-old man, who underwent transradial primary coronary angiography due to ST-elevation myocardial infarction. Two months later, he noticed a pulsatile mass on his hand where the catheterization was done. Ultrasonography proved the diagnosis of a pseudoaneurysm. Consequently, a TR Band® was applied to compress the mass. Interestingly, 24 hours later, ultrasonography confirmed a thrombosed pseudoaneurysm and the pulsatile mass had completely disappeared gradually without recurrence at 2 months' follow-up. Hence, this case report aims to propose the TR Band® as an effective noninvasive method for the treatment of pseudoaneurysms following catheterization.

7.
J Tehran Heart Cent ; 12(4): 188-191, 2017 Oct.
Article in English | MEDLINE | ID: mdl-29576788

ABSTRACT

Superior vena cava (SVC) syndrome is a medical condition resulting from the obstruction of the blood flow through the large central veins. Recently, central venous catheters have been reported as the increasingly common cause of this syndrome. We describe a 56-year-old woman with previous history of metastatic colon cancer, who had recently undergone central venous catheter insertion for her second chemotherapy course. Eight days following port insertion, she presented with signs and symptoms suggestive of acute SVC syndrome, which was successfully managed with catheter-directed thrombolysis. The pre-discharge transesophageal echocardiography and conventional angiography showed a patent SVC. The patient was discharged and remained asymptomatic over a 6-month follow-up. This case shows that catheter-directed thrombolysis may be used as a safe treatment for catheter-induced acute SVC syndrome in patients who have undergone catheter insertion in the central vein.

8.
Case Rep Cardiol ; 2016: 5189741, 2016.
Article in English | MEDLINE | ID: mdl-27437150

ABSTRACT

Takotsubo cardiomyopathy (TCM) is a stress-induced cardiomyopathy that occurs primarily in postmenopausal women. It mimics clinical picture of acute coronary syndrome with nonobstructive coronary arteries and a characteristic transient left (or bi-) ventricular apical ballooning at angiography. The exact pathogenesis of TCM is not well recognized. Hereby we present an unusual case of TCM that presents with signs and symptoms of acute pericarditis and was also found to have a coexisting coronary muscle bridge on coronary angiography. We discuss the impact of these associations in better understanding of the pathogenesis of TCM.

9.
Indian J Physiol Pharmacol ; 60(1): 30-7, 2016.
Article in English | MEDLINE | ID: mdl-29953191

ABSTRACT

The aim of the present study was the evaluation bleeding time (BT) in comparison to Urinary 11-dehydro thromboxane B2 (TXB2) regarding different ASA frequent dosages used in Borujerd city. This is a double blind randomized clinical trial on 370 subjects aged 35 years and older, referred to clinical offices in Borujerd. All ischemic heart disease's patients were randomly assigned to 4 ASA dose groups (80 mg, 81 mg, 100 mg and 325 mg) and one group-matched control group without any IHD. BT was measured by Ivy method; TXB2 was measured in a urine sample, both at least 5 days after ASA consumption. Probale AR was indicated if TXB2 was normal or higher than normal higher limit values, or BT was normal or lower than normal higher values. (IRCT201202026958N3) Probale AR was present in 37.6% and 64% resistance by BT and TXB2, respectively. All 4 treated groups had higher TXB2 levels than the control group/normal values (p>0.05). Also, urinary TXB2 level correlated positively with BT. Given the simplicity and low costs of its performance it might be of some potential use in developing countries. However, due to IVY method limitations it cannot be perceived as a tool to assess such specific aspects of platlat function or aspirin resistance.


Subject(s)
Aspirin/pharmacology , Bleeding Time , Myocardial Ischemia/drug therapy , Platelet Aggregation Inhibitors/pharmacology , Thromboxane B2/analogs & derivatives , Adult , Aged , Aspirin/administration & dosage , Dose-Response Relationship, Drug , Double-Blind Method , Female , Humans , Male , Middle Aged , Myocardial Ischemia/physiopathology , Myocardial Ischemia/urine , Platelet Aggregation Inhibitors/administration & dosage , Thromboxane B2/urine
10.
Int Cardiovasc Res J ; 8(4): 156-60, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25614859

ABSTRACT

BACKGROUND: There is evidence that inflammation may be involved in pathogenesis of MetS. Inflammatory biomarkers are moving to the forefront as the potent predictors of MetS. OBJECTIVES: The present study aimed to evaluate the association between MetS and some inflammatory biomarkers. PATIENTS AND METHODS: This community-based cross-sectional study was conducted on 800 subjects aged above 35 years selected through random sampling in Borujerd (west of Iran) from 2011 to 2013. MetS was defined based on ATP III criteria and the subjects were divided into two groups (MetS and non-MetS groups). Waist circumference and Body Mass Index (BMI) were calculated. In addition, blood samples were taken and C-Reactive Protein (CRP), lipid profile, Fasting Blood Sugar (FBS), and Bleeding Time (BT) were measured. Then, the correlations between MetS and the above-mentioned variables were estimated. After all, the data were entered into the SPSS statistical software (v. 17) and analyzed using T-test, chi-square, median test, and spearman's rank correlation. RESULTS: In this study, 344 subjects (43%) met the ATP III criteria. The results showed a significant difference between MetS and non-MetS groups regarding BMI, white blood cell, total cholesterol, LDL, platelet, and high-sensitivity CPR (hs-CRP) (P < 0.0001, P = 0.040, P < 0.0001, P < 0.0001, and P = 0.045, respectively). Besides, waist circumference, Triglyceride (TG), FBS, and systolic and diastolic blood pressure were significantly higher, while HDL was significantly lower in the MetS group (P < 0.0001). CONCLUSIONS: The incidence rate of MetS in our survey was higher compared to the previous reports. In addition, this incidence rate was higher in females in comparison to males. The results also showed a significant correlation between inflammatory biomarkers and MetS and that the higher levels of hs-CRP were associated with higher rate of MetS.

11.
J Tehran Heart Cent ; 8(1): 28-34, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23646045

ABSTRACT

BACKGROUND: Significant elevation of cardiac biomarkers after percutaneous coronary intervention (PCI) is associated with increased mortality. However, clinical importance of lesser degrees of cardiac enzyme elevation has not been well understood. Multiple factors might have an etiologic role, and the incidence of myonecrosis has not changed dramatically despite pharmacological and technological advances in PCI. The aim of this study was to evaluate the role of intracoronary (IC) Adenosine in preventing the elevation of cardiac enzymes as a marker of myonecrosis after PCI in patients with chronic stable angina. METHODS: Two hundred sixty patients with chronic stable angina who were candidates for PCI were randomly assigned to double-blinded pretreatment with IC Adenosine or placebo before crossing of the guide wire. The patients were observed during the hospital course, and blood samples were obtained in standard intervals after the intervention for cardiac biomarkers. The primary end point of this study was post-PCI myonecrosis, and secondary end point was safety of IC Adenosine administration in the setting of PCI in patients with chronic stable angina. RESULTS: Of the 260 patients, who were initially randomized, finally 83 patients were analyzed in the placebo and 96 in the Adenosine arms. The study patients were comparable in clinical and angiographic characteristics. The mean of the patients' age was 57.3 years (range = 35 to 79 years), and 71.5% were male. There were no differences in the mean serum cardiac biomarkers between the study groups (mean creatine kinase-MB [CK.MB] level of 29.5 ± 14.5 IU/L in the placebo group and 31.5 ± 18.5 IU/L in the control group; p value = 0.41; mean cardiac troponin I (cTnI) level of 0.097 ± 0.178 µg/L in the placebo group and 0.167 ± 0.5 µg/L in the control group; p value = 0.24). CONCLUSION: Despite promising results in primary PCI, our study showed that a strategy of IC Adenosine pretreatment is not beneficial in reducing post-PCI myonecrosis in patients with chronic stable angina and should not be routinely used.

12.
ARYA Atheroscler ; 8(1): 46-9, 2012.
Article in English | MEDLINE | ID: mdl-23056101

ABSTRACT

BACKGROUND: Fibrinolytic therapy is the standard therapeutic method for patients with acute myocardial infarction (AMI). This study endeavored to assess the delay in arrival to the emergency department and door to needle time for thrombolytic therapy. METHODS: This study was conducted on 80 patients with AMI whom referred to our clinic from January 2009 to January 2010. We measured time of arrival, needle time and door to needle time for all patients. Moreover, the relations of these times to some variables such as age, gender and the referred shift of emergency department personnel were calculated. RESULTS: A total of 80 patients, 62 (77.5%) male and 18 (22.5%) female were evaluated for thrombolytic therapy. The arrival time of overnight shifts was 14.59 ± 1.23 minutes shorter than other shifts. The median door to needle time was 46.56 minutes and the mean time of the onset of chest pain to arrival at the emergency department was 19.44 minutes. Seventy-two patients (90%) received fibrinolytic therapy within the first 30 minutes of arrival. The needle time was significantly longer in the night shift (P < 0.05) (between 8 to 14 minutes), while the time of receiving Streptokinase therapy in the other shifts was not meaningfully different. Finally there was a statistically significant difference between the referred shifts and needle time (P < 0.05). CONCLUSION: Despite our good results for door to needle time, to improve and attain the gold standard's limits in administering fibrinolytic therapy, improvement of policies like training the personnel to shorten this time is recommend.

13.
ARYA Atheroscler ; 8(3): 136-42, 2012.
Article in English | MEDLINE | ID: mdl-23358456

ABSTRACT

BACKGROUND: Bleeding time test is used to assess the function of platelets in human body. The aim of this project was thus to estimate the sample size required to determine the normal range of bleeding time (BT) in Borujerd (a city in Iran). A pilot study was designed to determine the range of normal BT in a small group of normal people. The total sample size for the next study was then calculated according to the results. METHODS: In order to determine the sample size, a total of 33 volunteers participated in this study. The normal range of BT was determined by Ivy method. Written informed consents were obtained from all participants and their clinical history was recorded. The sampling was performed once for each participant. However, the results were interpreted by two observers. The study protocol was approved by the Ethics Committee of the research center at Lorestan University of Medical Sciences (Iran). RESULTS: In this study, 33 normal participants (20 women and 13 men) were divided into four age groups of 35-44, 45-54, 55-64 and over 64 years old. Maximum and minimum BTs in men were 209 (in the age group of 35-44 years) and 150 seconds (in the age group of over 64 years), respectively. On the other hand, the corresponding values in women were 194 (in 55-64 year-old subjects) and 145 seconds (in women over 64 years of age). Considering the aforementioned results, the total sample size for the next study was determined to be 580 normal subjects by two-sample t-test power analysis at a power of 0.91816. CONCLUSION: There was a significant difference between the normal range of BT in participants of Borujerd and previously recorded range in other studies. Moreover, normal BT in men decreased by aging. This study did not show any special order in increasing or decreasing BT in women.

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