53 research outputs found

    Dynamic accommodation measurement using Purkinje reflections and ML algorithms

    Full text link
    We developed a prototype device for dynamic gaze and accommodation measurements based on 4 Purkinje reflections (PR) suitable for use in AR and ophthalmology applications. PR1&2 and PR3&4 are used for accurate gaze and accommodation measurements, respectively. Our eye model was developed in ZEMAX and matches the experiments well. Our model predicts the accommodation from 4 diopters to 1 diopter with better than 0.25D accuracy. We performed repeatability tests and obtained accurate gaze and accommodation estimations from subjects. We are generating a large synthetic data set using physically accurate models and machine learning

    Relationship between blood pressure levels and bone mineral density in postmenopausal Turkish women

    Get PDF
    WOS: 000290915100012PubMed: 22291766Introduction: We investigated the association between bone mineral density (BMD) detected by dual-energy X-ray absorptiometric (DXA) method and blood pressure (BP) in a large sample of postmenopausal women. Material and methods: The current study was based on a retrospective analysis of 586 postmenopausal women with a mean age of 60.8 +/- 8.8 years, who were screened for osteopenia or osteoporosis by DXA. Patients with hypertension (HT, n = 306) were compared with normotensive (NT, n = 290) individuals. Bone mineral density results for the femur neck and spine were classified into 3 groups according to World Health Organization criteria: normal (T score > -1.0 SD), osteopenia (T score -1.0 to -2.5 SD) and osteoporosis (T score <-2.5 SD). Patients with osteopenia or osteoporosis (T score < -1.0 SD) were grouped as having low bone mass (LBM). Results: There were no significant differences in femur T score, femur BMD, femur Z score, spinal T score, spinal BMD and spinal Z score between hypertensive and normotensive groups. The group of patients with low bone mass calculated from femur T scores had higher age, systolic BP, duration of hypertension and duration of menopause, but lower BMI. Similarly, patients with low spine BMD had higher age and duration of menopause, but lower BMI. Linear regression analysis showed a significant correlation between systolic BP and femur BMD and T score values. Furthermore, logistic regression analysis revealed that hypertension is an independent predictor of spinal osteopenia and osteoporosis. Conclusions: The presence of hypertension is an independent predictor of spinal low bone density in Turkish women after menopause

    Effects of ivabradine therapy on heart failure biomarkers

    Get PDF
    Background: Heart rate (HR) reduction is associated with improved outcomes in patients with heart failure (HF) and biomarkers can be a valuable diagnostic tool in HF management. The primary aim of our study was to evaluate the short-term (6 months) effect of ivabradine on N-terminal pro B-type natriuretic peptide (NT-proBNP), CA-125, and cystatin-C values in systolic HF outpatients, and secondary aim was to determine the relationship between baseline HR and the NT-proBNP, CA-125, cystatin-C, and clinical status variation with ivabradine therapy. Methods: Ninety-eight patients (mean age: 65.81 ± 10.20 years; 33 men), left ventricular ejection fraction &lt; 35% with Simpson method, New York Heart Association (NYHA) class II–III, sinus rhythm and resting HR &gt; 70/min, optimally treated before the study were included. Among them, two matched groups were formed: the ivabradine group and the control group. Patients received ivabradine with an average (range of 10–15) mg/day during 6 months of follow-up. Blood samples for NT-proBNP, CA-125, and cystatin-C were taken at baseline and at the end of a 6-month follow-up in both groups. Results: There was a significant decrease in NYHA class in the ivabradine group (2.67 ± ± 0.47 vs. 1.85 ± 0.61, p &lt; 0.001). When ivabradine and control groups were compared, a significant difference was also found in NHYA class 6 months later (p = 0.013). A significant decrease was found in HR in the ivabradine and control groups (84.10 ± 8.76 vs. 68.36 ± ± 8.32 bpm, p = 0.001; 84.51 ± 10 vs. 80.40 ± 8.3 bpm, p = 0.001). When both groups were compared, a significant difference was also found in HR after 6 months (p = 0.001). A significant decrease was found in cystatin-C (2.10 ± 0.73 vs. 1.50 ± 0.44 mg/L, p &lt; 0.001), CA-125 (30.09 ± 21.08 vs. 13.22 ± 8.51 U/mL, p &lt; 0.001), and NT-proBNP (1,353.02 ± 1,453.77 vs. 717.81 ± 834.76 pg/mL, p &lt; 0.001) in the ivabradine group. When ivabradine and control groups were compared after 6 months, a significant decrease was found in all HF parameters (respectively; cystatin-C: p = 0.001, CA-125: p = 0.001, NT-proBNP: p = 0.001). Creatinine level was significantly decreased and glomerular filtration rate (GFR) was significantly increased in the ivabradine group (1.02 ± 0.26 vs. 0.86 ± 0.17, creatinine: p = 0.001; 79.26 ± 18.58 vs. 92.48 ± 19.88, GFR: p = 0.001). There was no significant correlation between NYHA classes (before and after ivabradine therapy) and biochemical markers, or HR. Conclusions: In the outpatients with systolic HF, persistent resting HF &gt; 70/min with optimal medical therapy, the NT-proBNP, CA-125, and cystatin-C reductions were obtained with ivabradine treatment. Measurement of NT-proBNP, CA-125, and cystatin-C may prove to be useful in biomarker panels evaluating ivabradine therapy response in HF patients.

    Volume CXIV, Number 4, November 7, 1996

    Get PDF
    Objective: Turner syndrome (TS) is a chromosomal disorder caused by complete or partial X chromosome monosomy that manifests various clinical features depending on the karyotype and on the genetic background of affected girls. This study aimed to systematically investigate the key clinical features of TS in relationship to karyotype in a large pediatric Turkish patient population.Methods: Our retrospective study included 842 karyotype-proven TS patients aged 0-18 years who were evaluated in 35 different centers in Turkey in the years 2013-2014.Results: The most common karyotype was 45,X (50.7%), followed by 45,X/46,XX (10.8%), 46,X,i(Xq) (10.1%) and 45,X/46,X,i(Xq) (9.5%). Mean age at diagnosis was 10.2±4.4 years. The most common presenting complaints were short stature and delayed puberty. Among patients diagnosed before age one year, the ratio of karyotype 45,X was significantly higher than that of other karyotype groups. Cardiac defects (bicuspid aortic valve, coarctation of the aorta and aortic stenosis) were the most common congenital anomalies, occurring in 25% of the TS cases. This was followed by urinary system anomalies (horseshoe kidney, double collector duct system and renal rotation) detected in 16.3%. Hashimoto's thyroiditis was found in 11.1% of patients, gastrointestinal abnormalities in 8.9%, ear nose and throat problems in 22.6%, dermatologic problems in 21.8% and osteoporosis in 15.3%. Learning difficulties and/or psychosocial problems were encountered in 39.1%. Insulin resistance and impaired fasting glucose were detected in 3.4% and 2.2%, respectively. Dyslipidemia prevalence was 11.4%.Conclusion: This comprehensive study systematically evaluated the largest group of karyotype-proven TS girls to date. The karyotype distribution, congenital anomaly and comorbidity profile closely parallel that from other countries and support the need for close medical surveillance of these complex patients throughout their lifespa

    Omdlenie spowodowane hiperkaliemią podczas stosowania terapii skojarzonej inhibitorem konwertazy angiotensyny i spironolaktonem

    Get PDF
    A 76 year-old woman with a history of coronary artery bypass grafting and prior myocardial infarction was transferred to the emergency room with loss of consciousness due to marked bradycardia caused by hyperkalemia. The concentration of serum potassium was high, and normal sinus rhythm was restored after correction of the serum potassium level. The cause of hyperkalemia was considered to be several doses of spiranolactone, an aldosterone antagonist, in addition to the long-term intake of ramipril, an ACE inhibitor. This case is a good example of electrolyte imbalance causing acute life-threatening cardiac events. Clinicians should be alert to the possibility of hyperkalemia, especially in elderly patients using ACE/ARB in combination with potassium sparing agents and who have mild renal disturbance. Kardiol Pol 2010; 68, 9: 1043-104

    Ostra zakrzepica w stencie skutecznie leczona dowieńcowym podaniem tirofibanu

    No full text
    Acute stent thrombosis (AST) is occasionally observed during percutaneous coronary intervention in patients with acute coronary syndrome (ACS). It may jeopardize hemodynamic status. Currently, there is no adequate solution for this problem. We report our experience with an ACS patient who developed AST associated with cardiogenic shock after percutaneous coronary stent deployment. Intracoronary administration of tirofiban immediately restored the coronary flow of the target vessel, and the disastrous condition was reversed. Our experience suggests that intracoronary administration of tirofiban can be considered as an option in cases of AST during percutaneous coronary intervention

    Myocardial necrosis markers in myocardial ischemia reperfusion (MI/R) injury: a review

    No full text
    Myocardial ischemia/reperfusion injury is one of the main causes of morbidity and mortality in the world. This injury is experienced by patients suffering from cardiovascular diseases such as coronary heart diseases and subsequently undergoing reperfusion treatments in order to manage the conditions. Ischemia can be especially detrimental to the heart due to its high energy demand. Several cellular alterations have been observed upon the onset of ischemia. The danger created by cardiac ischemia is somewhat paradoxical in that a return of blood to the tissue, termed reperfusion, can result in further damage. The serum markers of myocardial injury are used to help in establishing the diagnosis of myocardial infarction. Use of various biochemical markers, including lactate dehydrogenase (LDH), creatine kinase (CK) total enzyme activity, CK-MB activity, Myoglobin, CK-MB mass, cardiac troponin I (cTnI), and cardiac troponin T (cTnT) have been investigated for noninvasive assessment of reperfusion. It is hoped that further studies will help refine the clinical use of new biomarkers like hs-cTn immunoassays in myocardial injury. [Med-Science 2017; 6(1.000): 163-71

    Investigation of the functional single-nucleotide polymorphisms in the BCRP transporter and susceptibility to colorectal cancer

    No full text
    Breast cancer resistance protein (BCRP) protects tissues by actively transporting xenobiotics and their metabolites out of the cells. BCRP is expressed in the apical membrane of normal intestinal and colonic epithelium. The BCRP substrates include a number of structurally unrelated compounds, such as drugs, pesticides, carcinogens and endogenous compounds. Although the functional and common BCRP alleles, 34G>A and 421C>A, are shown to vary by ethnicity, their potential mechanism has not been adequately described with regards to affecting the susceptibility to colorectal cancer. The present study aimed to evaluate the effects of the BCRP variants on the susceptibility to colorectal cancer and to predict the individual responses to xenobiotics transferred by BCRP. BCRP 421C>A was significantly associated with the colorectal cancer risk (odds ratio, 16.12; P=0.005). These findings are the first results of BCRP allele distributions in the Turkish population and provide an understanding of the correlation between therapeutic approaches and etiology of colorectal cancer

    Genetic Variations in Phospholipase C-epsilon 1 (PLCE1) and Susceptibility to Colorectal Cancer Risk

    No full text
    Colorectal cancer (CRC) is the third most common cause of cancer-related mortality and causes almost a million deaths worldwide each year. Genetic and environmental factors have gained importance in CRC as well as other types of cancer due to contribution to development of malignancies. Phosholipase C-epsilon 1 PLCE1 is one of the phospholipase family of enzymes and controls cellular responses leading to cell growth, differentiation and gene expression. Therefore, it was evaluated the effects of PLCE1 variations on developing CRC. Rs2274223 was significantly associated with CRC risk (OR = 2.018) while rs3765524 did not significantly differ (p > 0.05). The findings are the first results of PLCE1 profiles in the Turkish and could provide an understanding of aetiology in CRC
    corecore