Heart Valve Disease Predict Mortality in Hemodialysis Patients: A Single Center Experience

Our aim is to investigate the clinical and laboratory findings affecting the mortality of the patients in 3 years follow‐up who underwent hemodialysis at our center. In this retrospective, observational cohort study, 432 patients who underwent hemodialysis at our center for at least 5 months were included. The first recorded data and subsequent clinical findings of patients who died and survived were compared. Two hundred and ninety patients survived, 142 patients died. The mean age of the patients who died was higher (63.4 ± 12.3 years, vs. 52 ± 16.1 years, P = 0.0001), 60.5% of them had coronary artery disease (P = 0.0001), 93.7% of them had a heart valve disease. Duration of hemodialysis (survived 57 [21–260] months; died 44 [5–183] months, P = 0.000) was lower in patients who died. Serum potassium level before dialysis (5.1 ± 0.6; 4.9 ± 0.7 mEq/L, P = 0.030), parathyroid hormone (435 [4–3054]; 304 [1–3145] pg/mL, P = 0.0001), albumin (3.9 ± 0.4; 3.8 ± 0.4 mg/dL, P = 0.0001) and Kt/V (1.48 ± 0.3; 1.40 ± 0.3, P = 0.019) levels were lower, C‐reactive protein (5[1–208]; 8.7[2–256] mg/L, P = 0.000) levels were higher in patients who died. Logistic regression analysis showed age (OR = 1.1), coronary artery disease (OR = 1.7) and more than one heart valve disease (OR = 2.4) are independent risk factors for mortality. Potassium level before dialysis (OR = 0.60), parathyroid hormone (OR = 0.99), and higher Kt/V (OR = 0.28) were found to be an advantage for survival. Age, coronary artery disease and especially pathology in more than one heart valve are risk factors for mortality. Heart valve problems might develop because of malnutrition and inflammation caused by the chronic renal failure.     

Genotoxic effects of chlorophenoxy herbicide diclofop-methyl in mice in vivo and in human lymphocytes in vitro

Diclofop-methyl (DM) is a chlorophenoxy derivative used in large quantities for the control of annual grasses in grain and vegetable crops. In this study, the genotoxic effects of DM were investigated by measuring chromosomal aberrations (CAs) in mouse bone-marrow cells and CA and the comet assay in human peripheral lymphocytes. Mice were treated with 15.63, 31.25, 62.5, and 125?mg/kg body weight of DM intraperitoneally for 24 hours, and 15.63-, 31.25-, 62.5-, 125-, and 250-μg/mL concentrations were applied to human lymphocytes for both 24 and 48 hours. In in vivo treatments, DM significantly, but not dose dependently, increased the total chromosome aberrations, compared to both negative and solvent controls. Cell proliferation was significantly, but not dose dependently, affected by all doses. In in vitro treatments, DM (except 15.63 μg/mL) significantly and dose dependently increased the frequency of chromosome aberrations. Also, 250 μg/mL of 48-hour treatment was found to be toxic. Cell proliferation was significantly and dose dependently affected by DM applications, when compared to negative control. In in vitro treatments, DM significantly decreased the mitotic index only at the highest concentration for 24 hours, and 62.5- and 125-μg/mL concentrations for 48 hours. In the comet assay, a significant and dose-dependent increase in comet-tail intensity was observed at 62.5-, 125-, and 250-μg/mL concentrations. The mean comet-tail length was significantly increased in all concentrations. Our results demonstrate that DM is genotoxic in mammalian cells in vivo and in vitro.     

Dynamic cell culturing and its application to micropatterned, elastin-like protein-modified poly(N-isopropylacrylamide) scaffolds

In this study a tissue engineering scaffold was constructed from poly(N-isopropylacrylamide) (pNIPAM) to study the influence of strain on cell proliferation and differentiation. The effect of surface chemistry and topography on bone marrow mesenchymal stem cells was also investigated. Micropatterned pNIPAM films (channels with 10 μm groove width, 2 μm ridge width, 20 μm depth) were prepared by photopolymerization. The films were chemically modified by adsorption of a genetically engineered and temperature sensitive elastin-like protein (ELP). Dynamic conditions were generated by repeated temperature changes between 29 °C and 37 °C. ELP presence on the films enhanced initial cell attachment two fold (Day 1 cell number on films with ELP and without ELP were 27.6 × 10⁴ and 13.2 × 10⁴, respectively) but had no effect on proliferation in the long run. ELP was crucial for maintaining the cells attached on the surface in dynamic culturing (Day 7 cell numbers on the films with and without ELP were 81.4 × 10⁴ and 12.1 × 10⁴, respectively) and this enhanced the ability of pNIPAM films to transfer mechanical stress on the cells. Dynamic conditions improved cell proliferation (Day 21 cell numbers with dynamic and with static groups were 180.4 × 10⁴ and 157.7 × 10⁴, respectively) but decreased differentiation (Day 14 specific ALP values on the films of static and dynamic groups were 6.6 and 3.5 nmol/min/cell, respectively). Thus, a physically and chemically modified pNIPAM scaffold had a positive influence on the population of the scaffolds under dynamic culture conditions.     

Dynamic multislice computed tomography findings for parotid gland tumors

OBJECTIVE: Our aim was to research the enhancement features of parotid gland masses in detail and characterize if the masses were Warthin tumors, adenomas, or malignant tumors. METHODS: The prospective study included 25 parotid tumors in 21 patients. Neck computed tomography (CT) was performed using a multislice CT unit. A full-neck CT examination was done at 30 seconds after completion of contrast injection, and then tumor-level images were obtained at 90 seconds and at 5 and 25 minutes. Computed tomography number (lesion density in Hounsfield units) was determined at each phase, and differences within and among tumor groups were statistically analyzed. Diagnoses were confirmed by histopathology. RESULTS: There were 11 Warthin tumors, 8 pleomorphic adenomas, 5 malignant tumors, and 1 basal cell adenoma. Ten Warthin tumors showed rapid contrast enhancement at 30 seconds and rapid reduction of enhancement from the first to the fourth phase. The basal cell adenoma showed also a peak enhancement at 30 seconds. Seven pleomorphic adenomas showed increased enhancement through the first 3 phases. Four malignant tumors showed peak enhancement at 90 seconds. Statistically significant differences within and among tumor groups were determined. CONCLUSIONS: The data suggest that peak tumor enhancement at 30 and 90 seconds, respectively, might identify Warthin and malignant tumors. Increased enhancement through all phases might be an indicator for diagnosing pleomorphic adenomas.     

Ventricular pre-excitation and cardiac hypertrophy mimicking hypertrophic cardiomyopathy in a Turkish family with a novel PRKAG2 mutation

BACKGROUND: Mutations in PRKAG2, the gene for the gamma2 regulatory subunit of AMP-activated protein kinase, cause cardiac hypertrophy and electrophysiological abnormalities. We identified a novel mutation in PRKAG2 causing familial ventricular pre-excitation and severe cardiac hypertrophy. METHODS AND RESULTS: We studied 30 members of one family and 120 healthy controls. Molecular analysis of PRKAG2 gene revealed one missense mutation in exon 14 which was confirmed by restriction enzyme digestion. We identified a G to A transition, resulting in a Glu506Lys substitution in the PRKAG2 gene in 8 of the family members, who all had cardiac hypertrophy and ventricular pre-excitation. High incidence of right ventricular hypertrophy and left ventricular outflow tract obstruction are other prominent features of this novel PRKAG2 mutation. Family members without mutation had no cardiac disease. The 120 unrelated healthy individuals did not show this mutation. CONCLUSIONS: Coexistence of unexplained ventricular hypertrophy and pre-excitation should prompt the diagnosis of PRKAG2 mutations and these patients should be referred for genetic analysis. The possible alteration of AMP-activated protein kinase activity due to genetic defects in PRKAG2 may serve as a template for developing more specific therapies in the treatment of patients with this mutation.     

Results of Treatment Methods in Cardiac Arrest Following Coronary Artery Bypass Grafting

Abstract   Background and aim of the study: Emergency re-revascularization and invasive/noninvasive interventions in intensive care unit (ICU) are two main treatment methods in cardiac arrest following coronary artery bypass grafting (CABG). We evaluated the short- and long-term consequences of these two methods and discussed the indications for re-revascularization. Methods: Between 1998 and 2004, a total of 148 CABG patients, who were complicated with cardiac arrest, were treated with emergency re-revascularization (n = 36, group R) and ICU procedures (n = 112, group ICU). Re-revascularizations are mostly blind operations depending on clinical/hemodynamic criteria. These are: no response to resuscitation, recurrent tachycardia/fibrillation, and severe hemodynamic instability after resuscitation. Re-angiography could only be performed in 3.3% of the patients. Event-free survival of the groups was calculated by the Kaplan-Meier method. Events are: death, recurrent angina, myocardial infarction, functional capacity, and reintervention. Results: Seventy percent of patients, who were complicated with cardiac arrest, had perioperative myocardial infarction (PMI). This rate was significantly higher in group R (p = 0.013). The major finding in group R was graft occlusion (91.6%). During in-hospital period, no difference was observed in mortality rates between the two groups. However, hemodynamic stabilization time (p = 0.012), duration of hospitalization (p = 0.00006), and mechanical support use (p = 0.003) significantly decreased by re-revascularization. During the mean 37.1 ± 25.1 months of follow-up period, long-term mortality (p = 0.03) and event-free survival (p = 0.029) rates were significantly in favor of group R. Conclusion: Better short- and long-term results were observed in the re-revascularization group.     

Linburg-Comstock anomaly in musicians.

Anomalous tendon connections from the flexor pollicis longus to the index finger flexor digitorum profundus cause lack of independent excursion of the flexor pollicis longus, first described in 1979 by Linburg-Comstock. This anatomical variation is potentially problematic for musicians. The purpose of this study was to evaluate the incidence of this anomaly in musicians and to operate on the symptomatic patients with a limited incision with the help of magnetic resonance imaging. We studied the incidence of the anomaly among 136 musician volunteers. A lower incidence rate of the anomaly was determined in this study. One of the symptomatic musicians was operated on and the tendinous connection was excised. Clinical examination of 136 volunteers suggested that the anomaly was present in 13% of the volunteers; unilateral in 9% and bilateral in 4%. Follow-up of the patient who was operated on revealed full pain-free function without any complaint. Surgical treatment although rarely necessary, is simple and effective.