Showing papers by "Mustafa Yilmaz published in 2005"

A Randomized Study Comparing Combined Spinal Epidural or General Anesthesia for Renal Transplant Surgery

Abstract: Introduction The appropriate anesthesia for renal transplantation requires minimal toxicity for patients and for the transplanted organ, as well as sufficient pain relief and maintenance of vital functions. The aim of this study was to determine how the anesthetic technique influences the outcome in patients after renal transplantation in terms of preoperative and intraoperative hemodynamic changes and blood gas changes. Methods Fifty adult patients undergoing renal transplantation were randomly divided into two groups receiving standardized general anesthesia or combined spinal and epidural anesthesia. Results Demographically both groups were similar. Total anesthesia time (202 ± 53 vs 186 ± 37 minutes) and surgical time (191 ± 52 vs 162 ± 31 minutes) did not differ between the groups. The heart rate and systolic blood pressure values of the groups as measured before induction and 5, 15, 20, 30, as well as 60 minutes thereafter did not differ between the groups. Neither the frequency of bradycardia (four vs two) nor of hypotension (six vs four) during anesthesia differed between regional versus general anesthesia groups. Conclusion Regional is an important alternative to general anesthesia during renal transplantation surgery in adult patients.

Synthesis of alkyl nitrile and alkyl benzonitrile derivatives of calix[4]arene and their polymer supported analogues: A comparative study in two-phase extraction systems

Abstract: The article describes the synthesis and extraction properties of new alkylnitrile and alkylbenzonitrile substituted calix[4]arene based polymers. These compounds have been synthesized via nucleophilic substitution reactions involving 5,11,17,23-tetra-tert-butyl-25,27-bis-(cyanomethoxy)-26,28-dihydroxycalix[4]arene (2a), 5,11,17,23-tetra-tert-butyl-25-(2-cyanobenzyloxy)-26,27,28-trihydroxycalix[4]arene (3a), or 5,11,17,23-tetra-tert-butyl-25,27-bis-(2-cyanobenzyloxy)-26,28-dihydroxycalix[4]arene (4a), with Merrifield’s resin (0.8 mM Cl/1.0 g resin). The two-phase extraction properties of ligands 2a–4a along with their polymers 2b–4b toward the selected metal cations and dichromate ( HCr 2 O 7 - / Cr 2 O 7 2 - ) anions are reported. Extraction studies with monomer 2a show selectivity for Hg2+, where as monomers 3a and 4a are selective for Cd2+ and Hg2+ cations. Nevertheless, due to the higher oxidative stability of nitrile groups, polymers 2b–4b have been developed as good extractants for transferring the selected metal cations and dichromate ( HCr 2 O 7 - / Cr 2 O 7 2 - ) anions from an aqueous into a dichloromethane phase.

Design and Synthesis of New Chiral Calix[4]arenes as Liquid Phase Extraction Agents for α-Amino Acid Methylesters and Chiral α-Amines

Abstract: The article describes the synthesis and extraction properties of new (S)-(-)-1-phenylethylamine substituted p-tert-butylcalix[4]arene/calix[4]arene. These compounds have been synthesized via nucleophilic substitution reactions involving 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetra(2-hydroxyethoxy)calix[4]arene (4a), or 5,11,17,23-tetra-H-25,26,27,28-tetra(2-hydroxyethoxy)calix[4]arene (4b) with (S)-(-)-1-phenylethylamine in dry THF. The extraction properties of ligands 5a and 5b towards the some selected α-amino acid methylesters and chiral α-amines are also reported. It has been observed that receptor 5a was an excellent ionophore for α-amino acid methylesters/α-amines and good extractant than 5b. However, both of the ligands did not display any selectivity towards the configurations of this species.

Kinetic study of Hg(II) transport through a bulk liquid membrane containing ester derivative of bis-calix[4]arene

Abstract: A kinetic study of Hg(II) transport from an aqueous donor solution into an aqueous acceptor solution through a bulk liquid membrane containing N,N′‐bis[carbonylmethoxy(5,11,17,23‐tetra‐tert‐butyl‐25,26,27‐tris‐(ethoxycarbonyl‐methoxy)calix(4)arenyl)]‐1,2‐diaminoethane as a carrier was studied. The kinetic parameters (k 1d, k 2m, k 2a, t max, R m max, J d max, J a max) for the transport were investigated in terms of the effect of temperature, the stirring rate, the carrier concentration, and the type of solvent. In this study, the pseudo‐first‐order apparent rate constant of the interfacial transport of the Hg(II) is determined by using the spectrophotometric method. The kinetics of the transport was analyzed in the formalism of two consecutive irreversible first‐order reactions. The membrane entrance and exit rate constants were increased with increasing of temperature, stirring rate, and carrier concentration. The membrane entrance and exit rate constants depended on the type of solvent and was ...

Transport Kinetics of Hg2+ Through Bulk Liquid Membrane Using Calix[4]arene Ketone Derivative as Carrier

Abstract: In this article, calix[4]arene ketone derivative was used as a carrier to transport Hg2+ ions from an aqueous solution into an aqueous receiving solution The kinetic parameters (k 1, k 2, R m max, t max, J d max, J a max) were investigated with influence of temperature, the solvent, and stirring rate and analyzed in the formation of two consecutive, irreversible first order reactions The membrane entrance rate, k 1, and the membrane exit rate, k 2, constants were increased with temperature and stirring rate and found to be dependent on the solvent type in the order CH2Cl2 > CHCl3 > CCl4 The activation energy was obtained as 528 kcal/mol from the slope of the Arrhenius plot for the case of maximum membrane exit flux, J a max This value indicates that the process is controlled by species diffusion

Synthesis and Metal Ion Recognition Properties of a Novel Chiral Calix[4](azoxa)crown-7

Abstract: A novel chiral calix[4](azoxa)crown-7 (9) has been synthesized and its metal ion recognition properties investigated. The starting reagents, chiral diamine 5 and calix[4]arene diacid chloride derivative 8, were prepared according to literature methods. 1H and 13C NMR data show that 9 exists in a cone conformation. In liquid–liquid extraction experiments, 9 exhibits selectivity for Li+ among the other alkali metals and a good extraction ability for transition metal cations, suggesting its potential use in different fields, such as a sensor for ions as well as for chiral molecules.

Polymer Supported Calix[4]arene Schiff Bases: A Novel Chelating Resin for Hg2+ and Dichromate Anions

Abstract: This article describes the synthesis and characterization of two new calix[4]arene Schiff bases and their polymeric resins. The extraction properties of these “proton switchable extractants” with alkali, transition, post transition metal cations and for dichromate anions are reported. The two new calix[4]arene based Schiff bases (5 and 6) have been synthesized from 5,17‐diformyl‐25,27‐dipropoxy‐26,28‐dihydroxycalix[4]arene (4) by treatment with 3‐amino‐methylpyridine and 1,8‐diaminooctane in two separate reaction flasks following the same procedure. Compounds 5 and 6 have been appended to a polymeric resin by treatment with Merrifield resin through a nucleophilic substitution reaction. The receptor compounds (3 and 5–8) do not extract alkali metal cations, but show some selectivity toward transition metal cations, and a particularly high selectivity to Hg2+ and Pb2+. The protonated forms of all of the calixarene‐based receptors are good extractants for transferring Cr2O7 2−/HCr2O7 − anions from an aqueous...

Transport of Hg2+ Ions across a Supported Liquid Membrane Containing Calix[4]arene Nitrile Derivatives as a Specific Ion Carrrier

Abstract: The transport behavior of Hg2+ from aqueous solution through a flat‐sheet‐supported liquid membrane (SLM) has been investigated by using of calix[4]arene derivatives (1 and 2) as carriers and Celgrad 2400 and 2500 as the solid support. The effect of solvent type and anions such as chloride and nitrate ions on the transport of Hg2+ was examined. Danesi mass transfer model was used to calculate the permeability coefficients for each parameter studied. The highest values of permeability were obtained with 2‐nitrophenyl ethyl ether (NPOE) solvent and the influence was found to be in the order, NPOE>chloroform>xylene. The transport efficiency on the supported liquid membrane was dependent on the type of carrier, its characteristics, and the type of the solvent.

Idiopathic Hypereosinophilic Syndrome Associated with Multiple Intracardiac Thrombi

Abstract: A 17-year-old man was referred for dyspnea, fatigue, and fever. Idiopathic hypereosinophilic syndrome was diagnosed. Transthoracic echocardiography demonstrated multiple intracardiac thrombi in the left ventricular apex. Dissolution of thrombi was not seen despite intensive medical therapy. The patient died because of cerebral embolus.

Left atrial mechanical functions in pre-eclampsia.

Abstract: Aim: To assess the effect of short-term pressure overload on left atrial (LA) mechanical function in pre-eclampsia. Methods: Twenty women with pre-eclampsia and 17 age-matched healthy pregnant women were included. LA volumes were measured echocardiographically at the time of mitral valve opening (Vmax), onset of atrial systole (p-wave at the electrocardiography = Vp) and mitral valve closure (Vmin) according to the biplane area-length method. Results: The mean age, gestational age, weight and body surface area were similar in pre-eclampsia and controls. The ventricular septal and posterior wall thickness were greater in pre-eclampsia (P < 0.001). There were no significant differences in LA diameter, Vmax, Vmin, Vp, LA-passive emptying volume, LA-passive emptying fraction, LA-active emptying volume, LA-active emptying fraction, conduit volume, LA-total emptying volume and LA-total emptying fraction between the groups. Conclusion: Left atrial mechanical function didn’t change in pre-eclampsia. We conclude that short-lasting pressure overload is not capable of inducing changes in LA function.

Hodgkin's disease and autoimmune hemolytic anemia: a case report.

Abstract: Objective: To report a case of Hodgkin’s disease presenting with immune hemolytic anemia. Clinical Presentation and Intervention: A 47-year-old man was admitted t

Kinetic study of Hg2+ transport through a liquid membrane containing calix[4]arene dinitrile oligomer as carrier

Abstract: In this article, calix[4]arene dinitrile‐oligomer (1) carrier was used as a carrier to transport Hg2+ ions from an aqueous solution into an aqueous receiving solution. The kinetic parameters (k1, k2, Rm max, tmax, Jd max, Ja max) were investigated with a temperature influence, solvent, and stirring rate, and analyzed in the formation of two consecutive, irreversible first order reactions. The membrane entrance rate, k1, and the membrane exit rate, k2, constants were increased with the temperature and stirring rate, and found to be dependent on the solvent type in order to CH2Cl2>CHCl3>CCl4. For the maximum membrane exit flux, Ja max, the activation energy was found from the slope of the linear Arrhenius relationship to be 4.78 kcal/mol, which indicates that the process is controlled by species diffusion.

Study on the transport kinetics of Hg2+ through calix-oligomer bulk liquid membrane

Abstract: In this article, a calix‐oligomer derivative is used (1) as a carrier to transport Hg2+ ions from an aqueous solution into an aqueuos receiving solution. The kinetic parameters were analyzed in the formation of two consecutive, irreversible first order reactions. The influence of temperature and solvent and stirring rate on the kinetic parameters (k1, k2, Rm max, tmax, Jd max, Ja max) have also been investigated. The membrane entrance rate, k1, and the membrane exit rate, k2, constants were increased with temperature and stirring rate. The membrane entrance and exit rate constants depend on the solvent type and are found to be in the order CH2Cl2>CHCl3>CCl4. For the maximum membrane exit flux, Ja max, the activation energy was found from the slope of the linear Arrhenius relationship to be 7.06 kcal/mol, which indicates that the process is controlled by species diffusion.

The Use of Anatomic M‐Mode Echocardiography to Determine the Left Atrial Appendage Functions in Patients with Sinus Rhythm

Abstract: Left atrial appendage (LAA) contractile dysfunction is associated with thrombus formation and systemic embolism LAA function is determined by its flow velocities and fractional area change This study was performed in order to determine the LAA functions with the anatomic M-mode echocardiography (AMME) Our study comprised 74 patients who had sinus rhythm and underwent transesophageal echocardiography (TEE) for various reasons LAA fractional change (LAAFAC) was measured by manual planimetry in a transverse basal short-axis approach and LAA emptying and filling velocities also were measured The AMME values were determined by an M-mode cross section from a cursor placed beneath the orifice of the LAA in transverse basal short-axis imaging From these values LAA fractional shortening (LAAFS) and ejection fraction (LAAEF) were calculated LAAEF was calculated by the Teicholz method The comparisons were conducted, and no correlations between the LAA late filling and the anatomic M-mode values were found (for LAAFS r = 018; P > 005 and for LAAEF r = 019; P > 005) There were significant but poor correlations among the LAA late emptying with the anatomic M-mode measurements (for LAAFS r = 026; P < 005 and for LAAEF r = 030; P < 001), whereas, there were significant and good correlations between the LAAFAC and the anatomic M-mode values (for LAAFS r = 075; P < 001 and for LAAEF r = 078; P < 001) There were significant differences between the valvular heart disease group and the normal group, and between the valvular heart disease group and the ASD group (for LAAFAC P < 001, for LAAEF P < 001, for LAAFS P < 001) There was no difference between the normal group and the ASD group Our study showed that the LAAEF and LAAFS in patients with sinus rhythm obtained via anatomical M-mode echocardiography is a new method, which can be used instead of left atrial appendage area change

Synthesis, Characterization and Investigation of Side Chain Length and/or Substituents Effect on the Liquid Crystal Properties of New Mesogens

Abstract: New substituted and unsubstituted phenol based mesogene series having an azo central linkage was synthesized by fixing phenol as rigid core unit with aromatic amine. The terminal –OH group was esterified successively by long alkyl chain acid chloride of variable length (n=2, 6, 11, 15, 17). All 25 synthesized compounds exhibit mesomorphism. The effect of side chain length and substituents on the stability of liquid crystals was studied. The study reveals that nitro substituent destabilizes nematic and smectic phases more than floro substituent. Furthermore, the transition temperature decreases as the length of side chain increases.

Treatment of Recurrent Gastrointestinal Bleeding with Recombinant Factor VIIa in a Patient with Bernard-Soulier Syndrome

Abstract: The Bernard-Soulier syndrome (BSS) is a rare disorder of platelet function which is characterized by a prolonged bleeding time, giant platelets, and thrombocytopenia. Treatment of hemorrhage in patients with BSS usually requires platelet transfusion, but alloimmunization frequently occurs after repeated transfusions. In such patients prevention of bleeding may be difficult. In the literature there are a few cases of patients with BSS suffering from recurrent bleedings and refractory to platelet transfusions who were treated successfully with factor VIIa. Here, we describe another BSS patient refractory to platelet transfusions who had presented with severe gastrointestinal bleeding and was treated successfully with recombinant factor VIIa.