Acıbadem Üniversitesi Açık Erişim Sistemi
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Comparison of the modified polyacrylamide gradient gel electrophoresis and high-performance liquid chromatography methods in determining LDL size
No full textObjectives In this study, we aimed to compare modified Krauss polyacrylamide gradient gel electrophoresis (PAGGE) and high-performance liquid chromatography (HPLC) methods in classification, quantification, and separation of lipoproteins and determining low-density lipoprotein (LDL) size. Methods Blood specimens were obtained from eighty-seven volunteers. We measured LDL size using the PAGGE method and HPLC method with total cholesterol (TC) and triglyceride (TG) peaks. In the PAGGE method, Coomassie Brilliant Blue (CBB) staining was used instead of Sudan black staining, unlike the original method. The relationship between PAGGE and HPLC methods was evaluated by Pearson correlation test and Passing-Bablok regression analysis. Agreement between them was evaluated by Kappa analysis and Bland-Altman plots. Results Statistically significant correlation was found between the LDL size with PAGGE and HPLC methods under the cholesterol curve (HPLC-TC) (r=0.924, p<0.001). Similarly, there was a statistically significant correlation between PAGGE and HPLC methods under the TG curve (HPLC-TG) (r=0.910, p<0.001). In the PAGGE method, within-day precision was found as 2\% and between-day precision as 3\%. It was determined agreement between HPLC-TC vs. HPLC-TG methods and HPLC-TG vs. PAGGE methods was higher than HPLC-TC vs. PAGGE (Kappa values0.68, 0.71, and 0.44, respectively). Conclusions The PAGGE method can be a reliable method for measuring LDL size. HPLC method under cholesterol and triglyceride peaks may be used in clinical practice interchangeably, but clinical decision limits should be different. In addition, our study demonstrated that measurement methods for LDL size could be simplified with several modifications.3JUL 1275-2824
Atrial fibrillation designation with micro-Raman spectroscopy and scanning acoustic microscope
No full textAtrial fibrillation (AF) is diagnosed with the electrocardiogram, which is the gold standard in clinics. However, sufficient arrhythmia monitoring takes a long time, and many of the tests are made in only a few seconds, which can lead arrhythmia to be missed. Here, we propose a combined method to detect the effects of AF on atrial tissue. We characterize tissues obtained from patients with or without AF by scanning acoustic microscopy (SAM) and by Raman spectroscopy (RS) to construct a mechano-chemical profile. We classify the Raman spectral measurements of the tissue samples with an unsupervised clustering method, k-means and compare their chemical properties. Besides, we utilize scanning acoustic microscopy to compare and determine differences in acoustic impedance maps of the groups. We compared the clinical outcomes with our findings using a neural network classification for Raman measurements and ANOVA for SAM measurements. Consequently, we show that the stiffness profiles of the tissues, corresponding to the patients with chronic AF, without AF or who experienced postoperative AF, are in agreement with the lipid-collagen profiles obtained by the Raman spectral characterization.1APR 191
UNNOTICED ETIOLOGY IN ORTHOPEDIC COMPLAINTS : CHRONIC MOUNTAIN SICKNESS
No full textObjective: Chronic mountain sickness (CMS) is a clinical syndrome with symptoms of polycythemia that may interfere with other nonspecific diseases. The current study aimed to investigate the symptoms of patients living at high altitudes, who initially presented complaints that seemed to be common orthopedic problems, and to examine their relationship with chronic mountain sickness. Materials and Methods: The prospectively collected data of 104 patients were retrospectively evaluated for serum hemo-globin (Hb) and hematocrit (Hct) levels, oxygen saturation (sO(2)), Qinghai CMS questionnaire score, alcohol and tobacco use, ``any history of acute mountain sickness, body mass index (BMI), blood pressure, heart rate, and duration of high-altitude living. Patients grouped according to the Qinghai score as healthy, mild, moderate or severe CMS. The groups were investigated in terms of parameters and demographic characteristics. Results: Of the 104 patients, 33 (31.7\%) had a mild CMS score >= 6 (28 patients, 6-10, 5 patients, 11-14 points)remaining patients had no CMS. The frequency of excessive erythrocytosis was 4.5\% in men and 3.3\% in women. There was a significant difference in Hb, Hct and sO(2) levels between the healthy and mild CMS groups (p<0.001). CMS score had a positive correlation with Hct (rho 0.381, p<0.001) and negative correlation between sO(2) levels (rho-0.432, p<0.001). Conclusions: CMS can be observed at lower altitudes than described in literature. In individuals living in high altitudes, some of the CMS symptoms may be confused with real orthopedic symptoms and orthopedists working in these areas should increase their awareness on this issue. In order to make an appropriate approach, other symptoms related to CMS should be questioned in patients living at high altitudes.198-1048
Obturator nerve endometriosis: A systematic review of the literature
No full textBackground: Symptomatic obturator nerve endometriosis is a rare condition. In this paper, we aim to review and discuss the characteristics of obturator nerve endometriosis in light of current literature.Methods: An electronic search was conducted using the PubMed/Medline database.Results: Symptomatic obturator nerve endometriosis is rareonly 8 cases have been reported in the literature. Symptoms including difficulty walking, weak thigh adduction and pain in the inner thigh, which are all related to obturator nerve function, could be seen in the case of the entrapment of the nerve by endometrial nodules. A history of recurrent symptoms during menstrual cycles and physical examination, combined with appropriate radiologic imaging, led to a suspicion of obturator nerve involvement.Conclusion: Early diagnosis and surgical treatment of obturator nerve endometriosis is essential to minimise the nerve damage caused by recurrent cycles of bleeding and fibrosis, which are characteristics of endometriosis. The laparoscopic minimally invasive technique is feasible for the surgery of obturator nerve endometriosis. It offers the advantage of precise discrimination of vital structures and excellent access to deep anatomic sites. What is new? Obturator nerve endometriosis may be a severe cause of chronic pelvic pain in women of reproductive age. Treatment may be achieved surgically and in experienced hands, laparoscopic surgery would be the preferred choice.3JUN219-2231
Burkitt lymphoma with a granulomatous reaction: an M1/Th1-polarised microenvironment is associated with controlled growth and spontaneous regression
No full textAims Burkitt lymphoma (BL) is an aggressive B-cell lymphoma that, in some instances, may show a granulomatous reaction associated with a favourable prognosis and occasional spontaneous regression. In the present study, we aimed to define the tumour microenvironment (TME) in four such cases, two of which regressed spontaneously. Methods and results All cases showed aggregates of tumour cells with the typical morphology, molecular cytogenetics and immunophenotype of BL surrounded by a florid epithelioid granulomatous reaction. All four cases were Epstein-Barr virus (EBV)-positive with type I latency. Investigation of the TME showed similar features in all four cases. The analysis revealed a proinflammatory response triggered by Th1 lymphocytes and M1 polarised macrophages encircling the neoplastic cells with a peculiar topographic distribution. Conclusions Our data provide an in-vivo picture of the role that specific immune cell subsets might play during the early phase of BL, which may be capable of maintaining the tumour in a self-limited state or inducing its regression. These novel results may provide insights into new potential therapeutic avenues in EBV-positive BL patients in the era of cellular immunotherapy.2JAN430-4428
Structural analysis of M1AP variants associated with severely impaired spermatogenesis causing male infertility
No full textBackground: Impaired meiosis can result in absence of sperm in the seminal fluid. This condition, namely non-obstructive azoospermia (NOA), is one of the reasons of male infertility. Despite the low number of studies on meiosis 1-associated protein (M1AP) in the literature, MIAP is known to be crucial for spermatogenesis. Recently, seven variants (five missense, one frameshift, one splice-site) have been reported in the MIAP gene as associated with NOA, cryptozoospermia and oligozoospermia in two separate studies. However, all missense variants were evaluated as variant of uncertain significance by these studies. Therefore, we aimed to analyze their structural impacts on the M1AP protein that could lead to NOA. Methods: We firstly performed an evolutionary conservation analysis for the variant positions. Afterwards, a comprehensive molecular modelling study was performed for the M1AP structure. By utilizing this model, protein dynamics were sampled for the wild-type and variants by performing molecular dynamics (MD) simulations. Results: All variant positions are highly conserved, indicating that they are potentially important for function. In MD simulations, none of the variants led to a general misfolding or loss of stability in the protein structure, but they did cause severe modifications in the conformational dynamics of M1AP, particularly through changes in local interactions affecting flexibility, hinge and secondary structure. Conclusions: Due to critical perturbations in protein dynamics, we propose that these variants may cause NOA by affecting important interactions regulating meiosis, particularly in wild-type M1AP deficiency since the variants are reported to be homozygous or bi-allelic in the infertile individuals. Our results provided reasonable insights about the MIAP structure and the effects of the variants to the structure and dynamics, which should be further investigated by experimental studies to validate.MAR 211
Age-Related Changes in Corneal Epithelial Thickness Measured with an Ultrasound Pachymeter
No full textBackground: There is increasing research on the aging process of the cornea and its effect on the corneal parameters measured objectively. Nevertheless, the association of corneal epithelial thickness (CET) with age has yet to be fully illustrated.Purpose: We aimed to measure CET in healthy subjects to determine its age-related variation by using an ultrasound device. Patients and Methods: A total of one hundred and three subjects were enrolled in this study and grouped according to age: Group 71 years. The CET and total central corneal thickness (CCT) of each subject were measured by the Sonogage Corneo-Gage Plus 2 (Cleveland, Ohio) ultrasound pachymeter. The relationships between thickness values, laterality, age groups, and gender were analyzed using the Jonckheere-Terpstra test. The Partial correlation test was employed to assess the effect of age on the CET and CCT. Results: The mean CET was 47.88 +/- 1.15 mu m, with no statistically significant gender-related difference between right and left eyes. In addition, the CCT difference detected between female and male eyes was insignificant. The difference in mean CET across age groups was statistically significant (p =0.029). The difference in mean CET of left eyes across age groups was statistically significant (p=0.031). The mean CET and left CET of the oldest group were significantly thinner than the younger groups.Conclusion: Ultrasound pachymeter of the corneal epithelium demonstrated that there was no correlation between age and CCT, or gender. The CET becomes thinner with age in the central zone in both genders and there is no difference between males and females. Based on these results, age has a negative effect on CET. These findings could offer further insight into age-related changes in the cornea.1461-14701
Evaluation of the Relationships between Obesity and Central Retinal Thickness, Retinal Nerve Fiber Layer, Intraocular Pressure, and Central Corneal Thickness in Children
No full textABSTRACT
Purpose: The purpose of this study was to investigate the effect of childhood obesity on the retinal nerve fiber layer (RNFL), retinal
thickness, central corneal thickness and intraocular pressure.
Method: Children with obesity (n:24) (Group 1; n:48 eyes) and healthy children (n:23) (Group 2; n:46 eyes) were included in the study.
Average RNFL thickness, central 1 mm diameter of foveal thickness (CFT) and subfoveal choroidal thickness (SFCT) were measured using
the fourier domain - optical coherence tomography (FD-OCT). Central corneal thickness (CCT) was measured using contact ultrasonic
pachymetry and intraocular pressure (IOP) using Goldmann applanation tonometry.
Results: The mean IOP in Group 1 was found to be significantly higher (p=0.002) and 16.1 ± 3.1 mmHg in group 1 and 13.6 ± 3.2
mmHg in group 2, respectively. Mean RNFL, CFT and SFCT significantly were lower in group 1 (p < 0.05) than group 2. The average
RNFL was detected to 107.9 ± 10.5 µm in group 1 and 112.6±11.8 µm in group 2, respectively (p=0.001). Mean CFT was found to be
231.6±14.4 µm in group 1 and 245.9±19.98 µm in group 2, respectively (p=0.001). The average SFCT was observed to 193.3±15.3 µm in
group 1 and 221 ± 25.1 µm in group 2, respectively (p<0.001). Although CCT was relatively higher in group 1, no statistically significant
difference was observed among the groups (p=0.08). There was a positive correlation between the presence of obesity and mean IOP
measurements (r = 0.847, p = 0.011), and besides a negative correlation was detected between mean RNFL thickness and mean weight
of the patients (r = -0.749, p = 0.039).
Conclusion: In current study, it should be kept in mind that elevated IOP and decrement of RNFL thickness in children with obesity
increased the risk of developing glaucoma, as well as decreased CFT and SFCT may form the basis for the development of macular diseases
in future