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Pneumonia is a disease caused by bacteria, viruses, and fungi that settle in the alveolar sacs of the lungs and can lead to serious health complications in humans. Early detection of pneumonia is necessary for early treatment to manage and cure the disease. Recently, machine learning-based pneumonia detection methods have focused on pneumonia in adults. Machine learning relies on manual feature engineering, whereas deep learning can automatically detect and extract features from data. This study proposes a deep learning feature extraction-based hybrid approach that combines deep learning and machine learning to detect pediatric pneumonia, which is difficult to standardize. The proposed hybrid approach enhances the accuracy of detecting pediatric pneumonia and simplifies the approach by eliminating the requirement for advanced feature extraction. The experiments indicate that the hybrid approach using a Medium Neural Network based on AlexNet feature extraction achieved a 97.9% accuracy rate and 98.0% sensitivity rate. The results show that the proposed approach achieved higher accuracy rates than state-of-the-art approaches., (© 2023. Australasian College of Physical Scientists and Engineers in Medicine.)

Context: Different vitamin D analogs might have advantages over calcitriol., Objective: To evaluate the effects of paricalcitol vs . calcitriol based vitamin D receptor activators on calcium-phosphate metabolism and pulse wave velocity in hemodialysis patients., Design: Observational, cross-sectional and 1 year follow-up study., Subjects and Methods: 181 hemodialysis patients were enrolled in this study as divided in to 5 groups based on vitamin D therapy. Baseline and 12 th month data on blood biochemistry, pulse wave velocity and cumulative dose of treatments were compared in each study group as well as in overall paricalcitol vs . calcitriol-based treatment groups., Results: From baseline to 12 th month, significant improvement in pulse wave velocity and parathyroid hormone was shown in paricalcitol-based treatment group without a significant change in calcium, phosphate, alkaline phosphatase. A significant increase in pulse wave velocity, serum phosphate levels, calcium x phosphate product and serum alkaline phosphatase levels were noted in calcitriol-based treatment group with no significant change in serum calcium and parathyroid hormone levels., Conclusion: Our findings revealed superiority of paricalcitol than calcitriol based vitamin D receptor activator therapy in terms of serum phosphate levels, CaxP product, dose requirement for vitamin D and the control of pulse wave velocity., Competing Interests: The authors declare that they have no conflict of interest., (©2023 Acta Endocrinologica (Buc).)

This study was conducted to investigate the agreement between laboratory hemoglobin (LabHb) measured in venous blood and noninvasive, spectrophotometric hemoglobin (SpHb) measurement and the usability of SpHb measurement in the transfusion decision-making in patients with thalassemia whose hemoglobin (Hb) was monitored by taking blood samples at frequent intervals and who were transfused. Cardiac pulse, oxygen saturation, Pleth variability index (PVI), and SpHb values were measured in patients who came to the hematology outpatient clinic for a control visit and whose Hb levels were planned to be measured. Venous blood samples were taken for LabHb measurement, which we accept as the gold standard. Cohen's kappa value was calculated for the agreement between SpHb measurements and LabHb values. The relationship and predictability between both measurement methods were evaluated by Pearson correlation analysis, a modified Bland-Altman plot and the linear regression model. In the study conducted with a total of 110 children with thalassemia, a moderate level of agreement between the two measurement methods (kappa = 0.370, p  < 0.0001) and a significantly high correlation between the two tests (r = 0.675) were found. The mean bias between the differences was found to be 0.3 g/dL (-1.27 to 1.86 g/dL). The sensitivity and the specificity of SpHb in identifying patients who needed transfusions (Hb <10.0 g/dL) were calculated as 92.2 and 57.1%, respectively. Our results suggest SpHb measurement may be used to screen anemia in hemodynamically stable hemoglobinopathy patients and even for transfusion decision-making with combination clinical findings.

Objective: To determine whether oxygen therapy with continuous positive airway pressure (CPAP) is superior to normobaric oxygen therapy in carbon monoxide poisoning., Methods: The study participants were 43 patients diagnosed with carbon monoxide poisoning between the dates 15 March and 30 June 2016 at the emergency department of an urban teaching hospital. The control group comprised patients who received normobaric oxygen therapy. The case group consisted of patients who underwent one-hour CPAP therapy. The primary outcome was the determination of the half-life of carboxyhemoglobin (COHb) with CPAP treatment. The CPAP and control groups were compared in terms of the reduction in COHb levels after 60 minutes of therapy., Results: The COHb level among patients in the CPAP group was lower in the 30th and 60th minutes. The half-life of COHb was apparently decreased in the CPAP group compared with the control group (control and case groups mean plasma half-life of COHb were 80.26 ± 12.70 and 36.20 ± 4.58 minutes, respectively)., Conclusion: The results of the present study demonstrate that CPAP therapy may be an effective option for oxygen therapy among patients with carbon monoxide intoxication; this is achieved by decreasing the half-life of COHb.

Background: Obstructive sleep apnea syndrome (OSAS) leads to right ventricular (RV) dysfunction and pulmonary hypertension (PH) in the later stages. Early determination of these conditions is very important., Objectives: We aimed to evaluate the correlations of pulmonary artery distensibility, right pulmonary artery fractional shortening (RPA-FS), and pulmonary artery stiffness (PAS) with PH among newly diagnosed OSAS patients., Methods: We prospectively evaluated 34 newly diagnosed OSAS patients and 28 controls. The study subgroups were determined according to the apnea-hypopnea index (AHI). All patients underwent a transthoracic echocardiographic examination. Conventional RV parameters, PAS, and RPA-FS parameters were measured., Results: RPA-FS was significantly lower in the OSAS group (p < 0.001) and positively correlated with tricuspid annular systolic excursion (TAPSE) (p = 0.047) and pulmonary acceleration time (PAT) (p = 0.006), and inversely correlated with systolic pulmonary artery pressure (sPAP) (p = 0.013), and PAS (p < 0.001). Consistent with this result, PAS was significantly worse in the patients with OSAS compared to the controls (27.1 ± 3.5 to 15.8 ± 2.7, p < 0.001), and inversely correlated with RPA-FS (p < 0.001), PAT (p = 0.001), and TAPSE (p = 0.035). PAS was positively correlated with sPAP (p = 0.001). There were statistically significant differences for both PAS and RPA-FS among the OSAS subgroups with regards to the severity of disease (p < 0.001). The correlation analyses showed a significantly positive correlation between RPA-FS and mean O2 saturation. RPA-FS was also inversely correlated with AHI. Similarly, PAS was positively correlated with AHI and arousal index., Conclusions: PAS and RPA-FS are worsened in patients with OSAS, and are correlated with PH and severity of OSAS.

Objectives: Liver transplant is a high-risk surgery for cardiac events. The risk of 30-day major cardiac adverse events is estimated at more than 5%. In this retrospective study, we evaluated our preoperative cardiac risk assessment approach., Materials and Methods: We evaluated 58 adult patients who underwent liver transplant between May 2011 and May 2015. Preoperative cardiac risk factors and results of diagnostic tests were noted. Patients were divided into 2 groups: patients with or without hepatocellular carcinoma. Electrocardiogram, echocardiogram, and treadmill tests were performed for preoperative cardiac evaluation in all candidates for liver transplant. Results of these tests showed our preference for myocardial perfusion scintigraphy and/or coronary angiography and heart catheterization., Results: Mean age of patients was 46.5 ± 14.5 years. The most common cardiovascular risk factor was family history of coronary artery disease (24.1%) in all patients. Diabetes mellitus (15.5%) was the most common risk factor in the patient group without hepatocellular carcinoma. Three patients had already known coronary artery disease (5.2%). Of 16 patients (27.6%) who underwent coronary angiography, 4 were in the hepatocellular carcinoma group. Coronary revascularization by stent implantation was necessary for 1 patient in the hepatocellular carcinoma group; 1 patient in the group without hepatocellular carcinoma underwent preoperative coronary bypass surgery., Conclusions: No consensus exists for cardiovascular risk stratification and preoperative cardiovascular evaluation of liver transplant candidates. Noninvasive stress tests are not always feasible for all liver transplant candidates because of poor mobility and poor exercise capacity. With early diagnoses of cardiovascular conditions and preventive recommendations, liver transplant can be performed safely before spread of the disease, which is essential for carcinoma patients. Angiographic evaluation of liver transplant candidates for hepatocellular carcinoma is strongly recommended.

Background and Aim:: Beta-blockers have unfavorable effects on metabolic parameters in hypertensive treatment. New generation beta-blockers with vasodilatory capabilities are superior to traditional beta-blockers, but studies examining their effects on metabolic parameters are still lacking. This study aimed to compare the effects of 2 new generation beta-blockers, carvedilol and nebivolol, on insulin resistance (IR) and lipid profiles in patients with essential hypertension., Methods:: This was a prospective, randomized, open-label, single-center clinical trial. A total of 80 patients were randomized into 2 groups: the carvedilol group (n = 40, 25 mg of carvedilol daily) and the nebivolol group (n = 40, 5 mg of nebivolol daily). Follow-up was performed for 4 months. Fasting plasma glucose, insulin levels, and the lipid profile (high-density lipoprotein [HDL], low-density lipoprotein [LDL], total cholesterol, triglyceride, apolipoprotein AI, and apolipoprotein B levels) were measured and IR was calculated by the homeostasis model assessment (HOMA) index. These variables were compared before and 4 months after treatment., Results:: Blood pressure and heart rate were significantly and similarly reduced in the carvedilol and nebivolol groups after treatment compared to those before treatment (both P < .001). Serum glucose ( P < .001), insulin ( P < .01), HOMA-IR (P < .01), HDL ( P < .001), LDL ( P < .001), total cholesterol ( P < .001), and apolipoprotein B ( P < .05) levels decreased in a similar manner in the carvedilol and nebivolol groups after treatment compared to those before treatment. Serum triglyceride and apolipoprotein AI levels did not change after treatment with both drugs., Conclusion:: New generation beta-blockers, carvedilol and nebivolol, efficiently and similarly decrease blood pressure. They have similar favorable effects on glucose, insulin, IR, and the lipid profile.

Objective: Increased red blood cell distribution width (RDW) is associated with severity of coronary artery disease (CAD). The aim of the present study was to retrospectively evaluate the relationship between CAD detected by coronary computed tomography angiography (CCTA) and RDW., Methods: Records of 291 patients who underwent 16-slice CCTA due to the presence of angina-like chest pain were retrospectively evaluated. Exclusion criteria were applied. Clinical characteristics, risk factors for CAD, and RDW values on CCTA were noted., Results: RDW levels in patients with CAD were significantly higher than in those with normal coronary arteries (NCAs) (15.50±1.57 compared to 14.80±1.41, p=0.001). Diabetes mellitus, hypertension, and history of smoking were significantly more common in the CAD group (p=0.018, p=0.007, and p=0.013, respectively). On multivariate logistic regression analysis, RDW (p=0.009 [odds ratio (OR): 1.352; 95% confidence interval (CI): 1.081-1.683]), age (p<0.001 [OR: 1.063; 95% CI 1.031-1.090]), and history of smoking (p=0.003 [OR: 2.672; 95% CI: 1.360-5.232]) were shown to be independent predictors for CAD detected by CCTA., Conclusion: The present results suggest that higher RDW levels are independently associated with presence of CAD detected by CCTA in patients without known CAD. Further studies are warranted to clarify the exact role of RDW in risk stratification.

Introduction: In this study, we aimed to investigate the effects of occupational therapy and psychosocial interventions on the interpersonal functioning and individual and social performance levels of corresponding patients under the heading of psychosocial treatment approaches in psychiatry clinics as well as the attitudes of the patients in regard to those interventions., Methods: In 2013, out of psychotic (schizophrenia, bipolar disorder/mania) and nonpsychotic (depression, obsessive compulsive disorder, alcohol dependence) inpatients in our clinic, 48 patients who participated in occupational activities were included in the study group and 43 patients who did not participate in these activities were included in the control group. We prepared and implemented a 3-item questionnaire constructed by our team, which probed the patients' thoughts on these occupational activities. The Interpersonal Functioning Scale (IFS) and Personal and Social Performance Scale (PSP) were applied to both groups on hospital admission and discharge; variations in scale scores were evaluated on par with sociodemographic variables, and the study and control groups were compared., Results: In total, 91% of the study group provided positive feedback regarding the aforementioned interventions. When comparing the study and control groups, the IFS variance score of the study group did not show a significant difference with respect to that of the control group. A statistically significant difference (p<0.0001) was observed in the PSP scores. Evaluation of the PSP of the occupational activities, focusing on sociodemographics and diagnostic labels, revealed a significant improvement in nonpsychotic patients (p=0.002) compared with psychotic patients, in females (p=0.001) compared with males, in unemployed patients (p=0.0001) compared with employed patients, in single patients (p=0.002) compared with married patients, in less-educated patients (p=0.004) compared with high school graduates, and in patients younger than 45 years (p=0.002) compared with those older than 45 years., Conclusion: The findings of our study showed coherence with the literature regarding similar studies conducted on psychotic subgroups. The results demonstrated significantly positive repercussions, specifically in the treatment of nonpsychotic patients; both groups benefited from occupational activities, as shown by improvements in all psychiatric inpatients' PSP scores in comparison with scores of the control group. We concluded that the recruitment of psychosocial treatment approaches enhanced personal and social performance in the patient groups, thereby leading to additional clinical benefits., Competing Interests: Conflict of Interest: No conflict of interest was declared by the authors.

Presence of a cardiac pacemaker or implantable cardioverter defibrillator (ICD) is a relative contraindication to magnetic resonance imaging (MRI). Biventricular ICDs are often used in the treatment of advanced heart failure; however, reports on experience with biventricular ICDs are lacking in the literature. In this case report, we describe a pacemaker-dependent patient with a biventricular ICD on whom an MRI of the lumbar spine was performed without having realized the presence of the ICD.

Objectives: Hematologic parameters, such as mean platelet volume, red-cell distribution width, and neutrophil-to-lymphocyte ratio, have prognostic value in multiple cardiac conditions such as stable angina pectoris, acute coronary syndromes, and heart failure. However, no previous studies have evaluated the association between hematologic parameters and asymptomatic graft rejection after heart transplant. We evaluated the role of hematologic parameters for detecting asymptomatic graft rejection after heart transplant., Materials and Methods: We retrospectively evaluated medical records of 47 adult patients who underwent orthotopic heart transplant between February 25, 2005, and July 6, 2014, in our hospital, noting their hematologic parameters before each biopsy. Two groups were created according to biopsy results: rejection and no-rejection., Results: We excluded 4 patients who died during the first month posttransplant owing to early complications. We evaluated 422 endomyocardial biopsy results of 43 adult patients (mean age, 43.4 ± 11.4 y; 14 women). Mean follow-up was 33 months. A total of 109 biopsies performed because of clinical suspicion of rejection were excluded. Red-cell distribution width levels were similar between groups (17.2% ± 2.6% in the rejection group and 17.1% ± 2.5% in the no-rejection group; P = .856). Neutrophil-to-lymphocyte ratio was similar between groups (7.8 ± 9.9 in the rejection group and 8.2 ± 9.7 in the no-rejection group; P = .791). Mean platelet volume levels were significantly lower in the rejection group (8.3 ± 1.3 fL) than in the no-rejection group (8.8 ± 1.8 fL) (P = .037) (Table 1)., Conclusions: According to our results, only lower mean platelet volume levels were significantly associated with asymptomatic graft rejection in patients with a transplanted heart. More detailed analyses are needed to exclude the effects of immunosuppressant drugs, and further studies are needed to clarify the exact role of hematologic parameters for detecting asymptomatic rejection after heart transplant.

Purpose: Aside from traditional factors (e.g., diabetes, age, and hypertension), some hematological parameters, such as neutrophil-to-lymphocyte ratio (NLR), red blood cell distribution width (RDW), and mean platelet volume (MPV), have increasingly been reported as measures of systemic inflammation and atherosclerosis in patients with end-stage renal disease (ESRD). This study aimed to determine whether there is an association between these hematological parameters and the extent of coronary artery disease (CAD) in patients with ESRD., Methods: A total of 149 consecutive ESRD patients (66 % males) without established CAD were studied. NLR, RDW, and MPV values in all patients were calculated from the complete blood count before coronary angiography. Angiographic views were assessed by an experienced interventional cardiologist, and the extent of CAD was evaluated by the Gensini score. The patients were divided into quartiles of the Gensini score., Results: Age, time on dialysis, calcium-phosphorus product, C-reactive protein levels, NLR, and MPV were significantly different among the groups (all p < 0.05). The Gensini score was correlated with age, time on dialysis (both p < 0.001), NLR (p = 0.004), and C-reactive protein levels (p = 0.034) and inversely correlated with left ventricular ejection fraction (p = 0.023). Multivariate regression analysis showed that age (p = 0.001), time on dialysis (p < 0.001), NLR (p = 0.001), and MPV (p = 0.005) were independent predictors of the extent of CAD., Conclusions: Aside from the well-known traditional factors, NLR and MPV are independent predictors of the extent of CAD in patients with ESRD.

Introduction: The incidence of coronary artery anomalies (CAAs) varies from 0.2% to 8.4%. Knowledge of such anatomical variations is important as coronary procedures are regularly performed these days. We aimed to find the coronary dominance pattern, intermediate artery (IMA) frequency and CAA incidence in our clinic, and compare them to those in the literature., Methods: The medical reports of 5,548 patients who had undergone coronary angiography (CAG) between 2005 and 2009 were retrospectively investigated. Dominance pattern and presence of IMA and CAA were recorded. CAAs were described using two different classifications: Angelini and Khatami's classification, and a new modified classification that was derived from Angelini and Khatami's classification. Some procedural details and clinical features of the patients with CAA were also investigated., Results: Coronary dominance pattern was: 81.6% right coronary artery, 12.2% circumflex artery and 6.2% co-dominant. IMA was present in 613 (11.0%) patients. The incidences of overall anomaly were 2.7% and 1.4%, according to the different classifications. Absent left main coronary artery, which was the most common anomaly in the present study, was found in 51 (0.9%) patients. Incidences of myocardial bridge, coronary arteriovenous fistulae and aneurysms were 1.1%, 0.2% and 0.3%, respectively., Conclusion: CAAs are generally asymptomatic, isolated lesions. Some may lead to anginal symptoms, myocardial infarction or sudden death. We found that CAA was associated with increased radiation and contrast exposure in patients who underwent CAG. This risk could be reduced if appropriate catheters were designed and training programmes on ostial cannulation were developed.

Introduction and Aims: Pulmonary hypertension (PH) is an independent predictor of increased mortality in patients on dialysis and those undergoing renal transplantation. We investigated PH and its association with vascular calcification and endothelial dysfunction in renal transplant patients., Methods: The records of 300 consecutive patients who underwent renal transplant in our center between 2005 to 2012 were evaluated. PH was defined as systolic pulmonary artery pressure (sPAP) ≥ 35 mm Hg. Demographic information, clinical characteristics, pulse wave velocity (PWv), and renal recessive indices (RRI) were collected and compared among patients with and without PH., Results: Eight patients in PH group (age 36 [19] years) and 87 subjects in nPH group (age 35 [9] years) were evaluated. Demographic and clinical characteristics and laboratory data of the 2 groups were similar. Additionally, sPAP was positively correlated with PWv (r = 0.263, P = .01). In multivariate analyses, RRI (P = .004), serum CRP (P = .025), and PWv (P = .001) were associated with pulmonary artery pressure., Conclusion: PH is significantly associated with arterial stiffness in renal transplant recipients who have a high risk for cardiovascular disease. Considering the common prevalence of cardiovascular diseases, including PH, we suggested that all patients with renal transplantation should be evaluated for regular echocardiographic examination in clinical practice., (Copyright © 2015 Elsevier Inc. All rights reserved.)

We propose a robust method for automated computation of heart rate (HR) from digital color video recordings of the human face. In order to extract photoplethysmographic signals, two orthogonal vectors of RGB color space are used. We used a dual tree complex wavelet transform based denoising algorithm to reduce artifacts (e.g. artificial lighting, movement, etc.). Most of the previous work on skin color based HR estimation performed experiments with healthy volunteers and focused to solve motion artifacts. In addition to healthy volunteers we performed experiments with child patients in pediatric intensive care units. In order to investigate the possible factors that affect the non-contact HR monitoring in a clinical environment, we studied the relation between hemoglobin levels and HR estimation errors. Low hemoglobin causes underestimation of HR. Nevertheless, we conclude that our method can provide acceptable accuracy to estimate mean HR of patients in a clinical environment, where the measurements can be performed remotely. In addition to mean heart rate estimation, we performed experiments to estimate oxygen saturation. We observed strong correlations between our SpO2 estimations and the commercial oximeter readings.

Background: Mechanical heart valve replacement has an inherent risk of thromboembolic events (TEs). Current guidelines recommend an international normalized ratio (INR) of at least 2.5 after mechanical mitral valve replacement (MVR). This study aimed to evaluate the effects of a low INR (2.0-2.5) on thromboembolic and bleeding complications in patients with mechanical MVR on warfarin therapy., Methods: One hundred and thirty-five patients who underwent mechanical MVR were enrolled in this study. The end points of this study were defined as TEs (valve thrombosis, transient ischemic attack, stroke) and bleeding (all minor and major bleeding) complications. Patients were followed up for a mean of 39.6 months and the mean INR of the patients was calculated. After data collection, patients were divided into 3 groups according to their mean INR, as follows: group 1 (n = 34), INR <2.0; group 2 (n = 49), INR 2.0-2.5; and group 3 (n = 52), INR >2.5., Results: A total of 22 events (10 [7.4%] thromboembolic and 12 [8.8%] bleeding events) occurred in the follow-up period. The mean INR was an independent risk factor for the development of TEs. Mean INR and neurological dysfunction were independent risk factors for the development of bleeding events. A statistically significant positive correlation was found between the log mean INR and all bleeding events, and a negative correlation was found between the log mean INR and all TEs. The total number of events was significantly lower in group 2 than in groups 1 and 3 (P = 0.036)., Conclusions: This study showed that a target INRs of 2.0-2.5 are acceptable for preventing TEs and safe in terms of bleeding complications in patients with mechanical MVR.

Purpose: Secondary hyperparathyroidism (SHPT) is a common feature in maintenance hemodialysis (MHD) patients. Inadequate treatment of SHPT has been associated with cardiovascular complications, and vitamin D therapy might influence the development of cardiovascular diseases. In the present study, we aimed to evaluate the effects of intravenous paricalcitol and calcitriol treatments on left ventricular mass index changes in MHD patients., Methods: We conducted an observational study with a 12-month follow-up duration to compare the outcomes of intravenous paricalcitol and calcitriol treatments in MHD patients. Eighty patients with moderate to severe SHPT were enrolled in the study. All the patients had normalized total serum Ca concentration <10.5 mg/dL, serum calcium-phosphorus product (Ca × P) <75, and parathyroid hormone level (PTH) level ≥300 pg/mL at the begining of the follow-up period., Results: The patients were divided into a paricalcitol group (n = 40) and a calcitriol group (n = 40). The demographic, clinical, and biochemical characteristics of the patients were similar at baseline. We observed significantly superior control of SHPT; lesser frequency of hypercalcemia and hyperphosphatemia, and Ca × P level elevations; and interruption of vitamin D treatment in the paricalcitol group. Moreover, we found no significant change in left ventricular mass index in the paricalcitol group, but found a significantly increased left ventricular mass index in the calcitriol group during the follow-up period (from 136.6 ± 35.2 g/m2 to 132.9 ± 40.4 g/m2 vs. from 137.2 ± 30.1 g/m2 to 149.4 ± 31.0 g/m2; p<0.044)., Conclusion: We observed that, compared with calcitriol therapy, paricalcitol therapy reduced the PTH concentrations more effectively without causing hypercalcemia and hyperphosphatemia and might have a substantial beneficial effect on the development of left ventricular hypertrophy.

We report our efforts in identifying optimal scanning laser microscope parameters to study cells in three-dimensional culture. For this purpose we studied contrast of extracellular matrix (ECM) mimics, as well as signal attenuation, and bleaching of red and green fluorescent protein labeled cells. Confocal backscattering, second harmonic generation (SHG), and autofluorescence were sources of contrast in ECM mimics. All common ECM mimics exhibit contrast observable with confocal reflectance microscopy. SHG imaging on collagen I based hydrogels provides high contrast and good optical penetration depth. Agarose is a useful embedding medium because it allows for large optical penetration and exhibits minimal autofluorescence. We labeled breast cancer cells' outline with DsRed2 and nucleus with enhanced green fluorescent protein (eGFP). We observed significant difference both for the bleaching rates of eGFP and DsRed2 where bleaching is strongest during two-photon excitation (TPE) and smallest during confocal imaging. But for eGFP the bleaching rate difference is smaller than for DsRed2. After a few hundred microns depth in a collagen I hydrogel, TPE fluorescence of DsRed2 becomes twice as strong compared to confocal imaging. In fibrin and agarose gels, the imaging depth will need to be beyond 1 mm to notice a TPE advantage.

Photon shot noise is the main noise source of optical microscopy images and can be modeled by a Poisson process. Several discrete wavelet transform based methods have been proposed in the literature for denoising images corrupted by Poisson noise. However, the discrete wavelet transform (DWT) has disadvantages such as shift variance, aliasing, and lack of directional selectivity. To overcome these problems, a dual tree complex wavelet transform is used in our proposed denoising algorithm. Our denoising algorithm is based on the assumption that for the Poisson noise case threshold values for wavelet coefficients can be estimated from the approximation coefficients. Our proposed method was compared with one of the state of the art denoising algorithms. Better results were obtained by using the proposed algorithm in terms of image quality metrics. Furthermore, the contrast enhancement effect of the proposed method on collagen fıber images is examined. Our method allows fast and efficient enhancement of images obtained under low light intensity conditions.

A decline in kidney function after contrast exposure is associated with a high risk of morbidity and mortality during hospitalization and over long-term periods. Several retrospective and recent prospective clinical trials have shown that statin therapy might prevent contrast-induced nephropathy in patients undergoing percutaneous coronary intervention. In this study, we aimed to assess the effects of statin therapies on renal function parameters in patients undergoing elective coronary angiography. One hundred and sixty patients undergoing elective coronary angiography were randomized equally into two groups: atorvastatin 40 mg/day group (statin started 3 days before coronary angiography) and an untreated control group. An additional 80 patients were included as a chronic statin therapy group. Serum creatinine, serum cystatin C, and glomerular filtration rate (GFR) were measured before and 48 h after coronary angiography. Cockcroft-Gault and Modification of Diet in Renal Disease (MDRD) equations were used to determine GFR. After coronary angiography, serum creatinine and GFR determined by MDRD were significantly better in patients using atorvastatin than those in controls (P = 0.002 and P = 0.004, respectively). Postprocedure serum creatinine, cystatin C, and GFR determined by MDRD were also significantly better in chronic statin therapy group than those in controls (P = 0.006, P = 0.003, and P = 0.004, respectively). There were no differences in renal function parameters between the short-term atorvastatin group and the chronic statin therapy group. Our data demonstrate that the use of short-term atorvastatin and chronic statin therapy may have a role in protecting renal function after elective coronary angiography.

Objectives: The potential for perioperative and late cardiovascular complications in liver transplant candidates makes careful preoperative risk assessment imperative. We sought to identify the determinants of coronary artery disease in liver transplant candidates., Materials and Methods: Liver transplant candidates with end-stage liver disease who were more than 40 years old and undergoing coronary angiography were retrospectively included in this study. Patients with known coronary heart disease or valvular heart disease were excluded. Symptoms, coronary artery disease risk factors, blood tests, electrocardiogram, echocardiography, treadmill stress test, myocardial perfusion scintigraphy, and coronary angiography results were recorded. A multivariable logistic regression model was used to assess the independent predictors of coronary artery disease., Results: A total of 139 patients (mean age, 52 +/- 8; 110 male [79%]) were included in the analysis. Coronary angiography revealed that 13 patients (9.4%) had coronary artery disease. The frequency of diabetes mellitus, stable angina symptoms, positive smoking status, presence of 2 or more risk factors for coronary artery disease, and mean low-density lipoprotein cholesterol levels were significantly higher in patients with coronary artery disease than in patients without coronary artery disease. The electrocardiogram, echocardiography, and noninvasive stress test results were not valuable tools in liver transplant candidates for the diagnosis of coronary artery disease. In multivariate analysis, typical angina symptoms and low-density lipoproteins cholesterol levels appeared to be independent factors that were predictive of coronary artery disease., Conclusions: Typical anginal symptoms and low-density lipoprotein cholesterol levels seem to be the best predictors of coronary artery disease in liver transplant candidates.

Extracellular matrices play important, but poorly investigated, roles in morphogenesis. Extracellular cellulose is central to regulation of pattern formation in plants, but among metazoans only tunicates are capable of cellulose biosynthesis. Cellulose synthase (CesA) gene products are present in filter-feeding structures of all tunicates and also regulate metamorphosis in the ascidian Ciona. Ciona CesA is proposed to have been acquired by lateral gene transfer from a prokaryote. We identified two CesA genes in the sister-class larvacean Oikopleura dioica. Each has a mosaic structure of a glycoslyltransferase 2 domain upstream of a glycosyl hydrolase family 6 cellulase-like domain, a signature thus far unique to tunicates. Spatial-temporal expression analysis revealed that Od-CesA1 produces long cellulose fibrils along the larval tail, whereas Od-CesA2 is responsible for the cellulose scaffold of the post-metamorphic filter-feeding house. Knockdown of Od-CesA1 inhibited cellulose production in the extracellular matrix of the larval tail. Notochord cells either failed to align or were misaligned, the tail did not elongate properly and tailbud embryos also exhibited a failure to hatch. Knockdown of Od-CesA2 did not elicit any of these phenotypes and instead caused a mild delay in pre-house formation. Phylogenetic analyses including Od-CesAs indicate that a single lateral gene transfer event from a prokaryote at the base of the lineage conferred biosynthetic capacity in all tunicates. Ascidians possess one CesA gene, whereas duplicated larvacean genes have evolved distinct temporal and functional specializations. Extracellular cellulose microfibrils produced by the pre-metamorphic Od-CesA1 duplicate have a role in notochord and tail morphogenesis.

Background: The significant potential for perioperative and late cardiovascular complications makes careful preoperative cardiac risk assessment imperative in liver transplantation candidates., Objective: To determine the sensitivity and specificity of myocardial perfusion scanning for detection of coronary artery disease (CAD) in liver transplantation candidates., Patients and Methods: We prospectively evaluated 93 liver transplantation candidates. Patients with known CAD were excluded. All patients, regardless of symptoms and risk factors, underwent myocardial perfusion scanning and coronary angiography., Results: Results of myocardial perfusion scanning were abnormal in 64 patients (68.8%) and normal in 29 patients (31.2%). Of patients with abnormal scans, only 6 (9.4%) had severe CAD at coronary angiography. None of the 29 patients with normal perfusion scans and the 24 patients with fixed defects had severe CAD; however, 6 of 40 patients (15.0%) with reversible perfusion defects had severe CAD at coronary angiography (P = .005). Alcoholic liver disease, reversible perfusion defects at myocardial perfusion scanning, left ventricular systolic dysfunction, and higher low-density lipoprotein (LDL) cholesterol and triglyceride levels were significantly associated with CAD. Defining reversible perfusion defects as a sign of ischemia, and fixed defects and normal perfusion as nonischemic, myocardial perfusion scanning had 100% sensitivity but 61% specificity for severe CAD. The test's accuracy was low (38%)., Conclusions: The results of reversible perfusion defects on myocardial perfusion scanning were sensitive but not specific for CAD in liver transplantation candidates. The high number of false-positive results decreased the test's accuracy.

In this study, we aimed to assess the factors associated with laboratory-defined aspirin resistance and the relationship of this laboratory-defined aspirin resistance with thrombolysis in myocardial infarction risk score, markers of cardiac necrosis, and inflammatory and thrombotic risk factors in patients with unstable angina or non-ST elevation myocardial infarction. Ninety-seven patients who were under aspirin therapy and hospitalized with unstable angina/non-ST elevation myocardial infarction were included in the study. Laboratory-defined aspirin sensitive and resistant groups were determined by platelet function analyzer; aspirin resistance was defined as collagen/epinephrine closure time less than 165 s. Laboratory-defined aspirin resistance was noted in 29 patients (29.9%), and non-ST elevation myocardial infarction was observed in 46 patients (47.4%). Patients in the group with laboratory-defined aspirin resistance had significantly higher thrombolysis in myocardial infarction risk scores (P < 0.001). When the details of cardiac myonecrosis markers were compared, baseline and follow-up creatine kinase-myocardial band and troponin I values were higher in laboratory-defined aspirin-resistant group. Multivariate analyses revealed that laboratory-defined aspirin resistance was an independent predictor of non-ST elevation myocardial infarction (P = 0.022). Laboratory-defined aspirin resistance is associated with non-ST elevation myocardial infarction, higher markers of cardiac necrosis and thrombolysis in myocardial infarction risk score in patients hospitalized with unstable angina/non-ST elevation myocardial infarction.

Background and Aim: Epicardial adipose tissue (EAT), which is thought to be a component of visceral adiposity, is associated with the metabolic syndrome. We aimed to test the hypothesis that echocardiographic EAT thickness can be a marker for the presence and severity of coronary artery disease (CAD)., Method and Results: In all, 150 patients (100 patients with CAD and 50 patients with normal coronary arteries by diagnostic coronary angiography; 65 women, 85 men; mean age 55.7+/-7.4 years) were enrolled. EAT thickness was measured using 2-D echocardiographic parasternal long- and short-axis views. EAT thickness measurements were compared with angiographic findings. EAT thickness was significantly higher in patients with CAD in comparison to those with normal coronary arteries (6.9+/-1.5 mm vs. 4.4+/-0.8 mm; P<0.001). Furthermore, EAT thickness increased with the severity of CAD (multivessel disease 7.4+/-1.2 mm vs. single vessel disease 5.7+/-1.7 mm; P<0.001). Gensini's score significantly correlated with EAT thickness (r=0.600, P<0.001). EAT thickness of > or = 5.2 mm had 85% sensitivity and 81% specificity (ROC area 0.914, P<0.001, 95% CI [0.86-0.96]) for predicting CAD., Conclusion: EAT thickness, which is easily and non-invasively evaluated by transthoracic echocardiography, can be an adjunctive marker to classical risk factors for the prediction of CAD.

Background: Aspirin (ASA) is frequently used to prevent cardiovascular events and improve renal graft function after renal transplantation. Clinical studies have demonstrated that decreased responsiveness to ASA therapy is associated with an increased risk of atherothrombotic events. However, no clinical trial to date has evaluated the incidence and clinical importance of ASA resistance among renal transplant recipients., Aim: To assess the incidence of ASA resistance and its association with cardiovascular risk factors (CRF) and renal graft function after renal transplantation., Methods: We prospectively included 40 patients undergoing living related donor renal transplantation using ASA (80 mg/d) in the study. ASA resistance was defined using a platelet function analyzer (PFA-100). Glomerular filtration rate (GFR) was measured by postoperative Tc-99m diethylenetriaminepentaacetic acid renal scintigraphy. We investigated the incidence of ASA resistance and its relationship to CRF and renal graft function., Results: ASA resistance was noted in 11 patients (27.5%). The demographic characteristics of the patients were similar in both groups (P > .05). Compared with patients in the ASA-sensitive group, patients in the ASA-resistant group showed significantly higher total cholesterol, low-density lipoprotein cholesterol, triglyceride, C-reactive protein, and fibrinogen levels and lower GFRs (44 +/- 21 mL/min vs 63 +/- 26 mL/min, P = .03). The incidence of ASA resistance was higher among patients with GFRs < 60 mL/min compared with those with a GFR >or= 60 mL/min (10% vs 1%; P = .012)., Conclusion: ASA resistance is associated with higher lipid levels and inflammatory and thrombotic cardiovascular risk factors and lower GFRs in renal transplant recipients.

Background: Atrial fibrillation (AF) occurs frequently after coronary artery bypass grafting (CABG) and often results in prolonged postsurgical hospital stays and increased mortality and morbidity. Beta blockers are known to prevent postoperative AF. In this prospective study, we investigated the efficacy of carvedilol compared with metoprolol succinate in preventing postoperative AF., Methods: Subjects included 110 patients (31 women, 79 men; mean age, 60+/-10 years, range, 39-82 years) who had undergone CABG. Patients were randomized to receive either metoprolol or carvedilol, and all patients received the drugs 3 days prior to surgery. Metoprolol was started at 50 mg twice daily and carvedilol was started at 12.5 mg twice daily. The doses were titrated according to the patients' hemodynamic responses. All patients were monitored for 3 days after the surgery., Results: Of the 110 patients, 55 (50%) were treated with metoprolol succinate, and 55 (50%) were treated with carvedilol. Baseline characteristics and operative data of the patients did not differ between groups. During follow-up, 20 patients (36%) in the metoprolol group and 9 patients (16%) in the carvedilol group developed AF (P=0.029). Multiple stepwise logistic regression analysis showed that metoprolol use, older age, and impaired left ventricular ejection fraction were independent risk factors for developing AF, and carvedilol use was found to be independently related to sinus rhythm maintenance after CABG (P=0.02)., Conclusions: These results show that carvedilol is superior to metoprolol in decreasing development of early postoperative AF.

Aspirin has the potential to influence C-reactive protein (CRP) levels, an inflammatory marker, by its anti-inflammatory activity. Persistently increased platelet reactivity, however, can be detected with different laboratory methods despite aspirin therapy in some patients. The aim of this study was to investigate the effects of increased platelet reactivity on CRP levels at rest and after exercise in patients with documented or suspected coronary artery disease. Blood samples were collected from 100 patients (age, 58.1+/-8.5 years; 63.0% men) who were treated with 100 or 300 mg/day enteric-coated aspirin for at least 7 days, before and immediately after treadmill test for CRP analyses. Platelet reactivity was measured by the standardized platelet function analyzer-100, and increased platelet reactivity was defined as a normal collagen/epinephrine closure time (<165 s). Of the 100 patients, 82 had normal platelet reactivity (group A) and 18 had increased platelet reactivity (group B). The CRP levels increase was statistically significant after exercise in patients with increased platelet reactivity [group A: 2.3 (1.4-4.3) to 2.8 (1.6-4.9) mg/l, P=0.09; group B: 3.3 (2.0-4.5) to 4.7 (2.9-8.5) mg/l, P=0.02]. Detecting increased platelet reactivity is associated with an increase in CRP levels. The clinical significance of this finding needs to be further investigated.

Some aspirin-treated patients experience thromboembolic events, a phenomenon termed 'aspirin resistance', which may be clinical or biochemical by definition. Physical exercise is known to enhance platelet secretion and aggregability. To evaluate the presence of biochemical aspirin resistance at rest and immediately after exercise in individuals with stable coronary artery disease or coronary artery disease risk factors. We prospectively enrolled 101 patients who had received 100 or 300 mg/day enteric-coated aspirin for at least 7 days. Biochemical aspirin resistance (defined as normal collagen-epinephrine closure time < 165 s) was studied using the standardized platelet function analyzer. Of the 101 patients, 63 were aspirin sensitive both at rest and immediately after exercise, 18 exhibited biochemical aspirin resistance both at rest and after exercise, and 20 were aspirin sensitive at rest but exhibited biochemical aspirin resistance immediately after exercise. The results of exercise testing were similar in all three groups (each P > 0.05). Our results indicate that in almost 20% of the patients, aspirin did not seem to protect against exercise-induced platelet activation, despite the presence of aspirin sensitivity at rest. We did not, however, determine the extent to which the biochemical aspirin resistance noted in our study applied to clinical events.