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A comprehensive study of photon interaction features has been made for some alloys containing Pd and Ag content to evaluate its possible use as alternative gamma radiations shielding material. The mass attenuation coefficient (μ/ρ) of the present alloys was measured at various photon energies between 81 keV–1333 keV utilizing HPGe detector. The measured μ/ρ values were compared to those of theoretical and computational (MCNPX code) results. The results exhibited that the μ/ρ values of the studied alloys are in the same line with results of WinXCOM software and MCNPX code results at all energies. Moreover, Pd75/Ag25 alloy sample has the maximum radiation protection efficiency (about 53% at 81 keV) and lowest half value layer, which shows that Pd75/Ag25 has superior gamma radiation shielding performance among the other compared alloys. Keywords: Alloys, Shielding material, MCNPX, Photon, HPGe detector

The lead element or its salts are good radiation shielding materials. However, their toxic effects are high. Due to less toxicity of bismuth salts, the radiation shielding properties of the bismuth salts have been investigated and compared to that of lead salts to establish them as a better alternative to radiation shielding material to the lead element or its salts. The transmission geometry was utilized to measure the mass attenuation coefficient (μ/ρ) of different salts containing lead and bismuth using a high-resolution HPGe detector and different energies (between 81 and 1333 keV) emitted from point sources of 133Ba, 57Co, 22Na, 54Mn, 137Cs, and 60Co. The experimental μ/ρ results are compared with the theoretical values obtained through WinXCOM program. The theoretical calculations are in good agreement with their experimental ones. The radiation protection efficiencies, mean free paths, effective atomic numbers and electron densities for the present compounds were determined. The bismuth fluoride (BiF3) is found to have maximum radiation protection efficiency among the selected salts. The results showed that present salts are more effective for reducing the intensity of gamma photons at low energy region. Keywords: Lead, Bismuth, Photon, HPGe detector, Radiation protection efficiency

In the present work, we determined the gamma-ray attenuation characteristics of eight different polymers(Polyamide (Nylon 6) (PA-6), polyacrylonitrile (PAN), polyvinylidenechloride (PVDC), polyaniline (PANI), polyethyleneterephthalate (PET), polyphenylenesulfide (PPS), polypyrrole (PPy) and polytetrafluoroethylene (PTFE)) using transmission geometry utilizing the high resolution HPGe detector and different radioactive sources in the energy range 81–1333 keV. The experimental linear attenuation coefficient values are compared with theoretical data (WinXCOM data). The linear attenuation coefficient of all polymers reduced quickly with the increase in energy, at the beginning, while decrease more slowly in the region from 267 keV to 835 keV. The effective atomic number of PVDC and PTFE are comparatively higher than the Zeff of the remaining polymers, while PA-6 possesses the lowest effective atomic number. The half value layer results showed that PTFE (C2F4, highest density) is more effective to attenuate the gamma photons. Also, the theoretical results of macroscopic effective removal cross section for fast neutrons (∑R) were computed to investigate the neutron attenuation characteristics. It is found that the ∑R values of the eight investigated polymers are close and ranged from 0.07058 cm−1 for PVDC to 0.11510 cm−1 for PA-6. Keywords: Polymer, Neutron, Gamma photon, Attenuation, Shielding

The mass attenuation coefficients, effective atomic numbers and electron densities of different parts (aerial parts, root and flower) of four medicinal aromatic plants (Pimpinella tragium subsp. lithophila, Scutellaria orientalis subsp. orientalis, Tanacetum abrotanifolium and Stachys byzantina c. koch) have been determined experimentally using transmission beam method for gamma energies of 13.92, 17.75, 20.78, 26.34 and 59.54 keV. The obtained mass attenuation coefficients, effective atomic numbers and electron densities were validated using WinXCOM program and good agreements were obtained for all samples. The aerial parts of the Scutellaria orientalis subsp. orientalis was found to having the maximum mass attenuation coefficients and effective atomic numbers values among the present samples. The root part of the Scutellariaorientalis subsp. orientalis has bigger values of effective electron density within the selected samples The effective atomic numbers for the present samples lie in the 3.117–6.932 range and the effective electron densities lie in the range of (0.272–1.672)x1025 electrons/g. Keywords: Medicinal aromatic plants, Radiation, Mass attenuation coefficient, Effective atomic number, Effective electron density

In this study, the gamma radiation attenuation features of barium zirconat, barium titanate (IV), magnesium nitride, barium pyrophosphate and silicon carbide were studied using the narrow beam geometrical setup in the energy range of 81 keV–1333 keV. The mass attenuation coefficients have been measured and then used to obtain half value layers, mean free paths and effective atomic numbers of the present materials. It is found that the change in the mass attenuation coefficient is considerable for low photon energies (between 81 and 276 keV), whereas the change in this parameter is comparatively small between 303 and 835 keV photon energies. At high energies (1173, 1275 and 1333 keV), the results showed that the mass attenuation coefficient values for all samples are almost the same which revealed that the present ceramics does not have a significant effect on the amount of attenuation of photon at higher energies. The radiation protection efficiency results revealed that BaZrO3 has the maximum capability in attenuation of gamma photons followed by BaTiO3 and Ba2P2O7, especially at low energies. Keywords: Gamma radiation, Attenuation, Ceramic, Effective atomic number, Radiation protection efficiency

The mass attenuation coefficients (μ/ρ) of food waste samples (pomegranate peel, acorn cap, lemon peel, mandarin peel, pumpkin peel, grape peel, orange peel, pineapple peel, acorn peel and grape stalk) have been measured employing a Si(Li) detector at 13.92, 17.75, 20.78, 26.34 and 59.54 keV. Also, the theoretical values of the mass attenuation coefficients have been evaluated utilizing mixture rule from WinXCOM program. The results showed that the lemon peel has the highest values of μ/ρ among the selected samples. From the obtained mass attenuation coefficients, we determined some absorption parameters such as effective atomic number (Zeff), electron density (NE) and molar extinction coefficient (ε). It was found that the Zeff values of all food wastes lie within the range of 4.034–7.595, whereas the NE of the studied food wastes was found to be in the range of 0.301–1.720 × 1025 (electrons/g) for present energy region. Keywords: Food waste, Photon, Mass attenuation coefficient, Effective atomic number, Molar extinction coefficient

Shielding parameter of eight (A–H) selected soil samples collected from different sites in Bingöl city and Genç district, Turkey have been comprehensively measured with fifteen different photon energies in the energy range from 13.94 keV to 88.04 keV. The soil samples were irradiated with 100 mCi 241Am, 10 mCi 133Ba and 40 mCi 109Cd radioactive point source using transmission geometry arrangement. The results were compared with those obtained by WinXCom and FFAST programs. The experimental results were found to be very close to both WinXCom and FFAST results. In addition, the effective atomic number, effective electron density, radiation protection efficiency and exposure buildup factor were determined using the obtained mass attenuation coefficients and standard formula. The results showed that the mass attenuation coefficients, as well as the effective atomic number of soil A and soil G, are relatively higher than those of other soils, which signify that both soils A and G provide superior shielding from gamma and X-rays. Keywords: Transmission geometry, Soil, Shielding parameters, Mass attenuation coefficient, Exposure buildup factor

Ionizing radiation is vital in various fields but poses health risks, necessitating effective shielding. This study investigated the photon-shielding properties of polyester-based ternary composites with barite (BaSO 4 ) and tungsten (W) using experimental methods, theoretical calculations, and Monte Carlo simulations for energies between 81 keV and 1332.5 keV. WINXCOM was utilized for the theoretical predictions, and the MCNP6 and PHITS 3.22 algorithms were employed for the simulations. According to the results, the simulation, theoretical, and experimental data all closely aligned. At 81 keV, the composite containing the highest amount of tungsten (PBaW50) had the highest mass attenuation coefficient (3.7498 cm 2 /g) and linear attenuation coefficient (12.9676 cm -1 ). Furthermore, for a sample that was 1 cm thick, PBaW50 offered 99.88% protection at 81 keV and had the lowest HVL and TVL values. PBaW50 exhibited attenuation capabilities, making it appropriate for use in industrial, medical, and aerospace settings. In summary, the findings of this study underscore the potential of polyester-based composites doped with barite and tungsten as effective materials for gamma radiation shielding. The PBaW50 sample, in particular, stands out for its attenuation performance, making it a viable option for a wide range of applications where durable and efficient radiation shielding is essential.

Context: Oligothiophenes have long been used as model compounds to understand the chemistry of polythiophenes. Herein, we have some quantum chemical calculations and intra- and inter-molecular interaction calculations of a series of oligothiophenes such as terthiophene, quintetthiophene, sevensthiophene, terthiophene-terthiophene, terthiophene-water, terthiophene-methanol, and terthiophene-chloroform performed by time-dependent density functional theory (TD-DFT), density functional theory (DFT), and Multiwfn: a multifunctional wavefunction analyzer. The UV-vis spectra, HOMO-LUMO energies, NBO analysis, MEP, molecular structures, and electronic properties were computed using DFT/TD-DFT at the level of B3LYP/6-31+ G (d,p) and described. The nature of molecular interactions between terthiophene and solvents like water, methanol, and chloroform were also investigated using non-covalent interaction index (NCI), reduced density gradient (RDG), localized orbital locator (LOL), and electron localization function (ELF) topological analyses. Besides, Fukui functions and energy of population density-of-states were computed using the same method. The calculation results show that there are some changes in the terthiophene with the addition of solvent to the medium., Methods: DFT calculations were performed using the Gaussian 09 software and GaussView 5.0 visulation program. Multiwfn software is used to calculate the reduced density gradient (RDG) scatterplots, non-covalent interactions (NCI), ELF, LOL, Fukui analysis, and energy of population density-of-states of oligothiophenes., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Essential oils are volatile oil-like liquids with a characteristic strong smell and taste. They are formed in plants and are then extracted. Essential oils have extremely strong physiological and pharmacological properties, which are used in the medicine, cosmetics, and food industries. In this study, the molecules caryophyllene oxide, β -pinene, 1,8-cineol, α-cubebene, and β-caryophyllene, which are the molecules with the highest contents in the essential oil of the plant mentioned in the title, were selected and theoretical calculations describing their interactions with water were performed. Because oil-water mixtures are very important in biology and industry and are ubiquitous in nature, quantum chemical calculations for binary mixtures of water with caryophyllene oxide, β-pinene, 1,8-cineol, α-cubebene, and β-caryophyllene were performed using the density functional theory (DFT)/B3LYP method with a basis of 6-31 G (d, p). Molecular structures, HOMO-LUMO energies, electronic properties, reactivity (ELF, LOL, and Fukui), and NCI-RDG and molecular electrostatic potential (MEP) on surfaces of the main components of Phlomis bruguieri Desf. essential oil were calculated and described.

The physicochemical properties of binary systems are of great importance for the application of the latter. We report on the investigation of an ammonium sulfamate-urea binary system with different component ratios using a combination of experimental (FTIR, XRD, TGA/DSC, and melting point) and theoretical (DFT, QTAIM, ELF, RDG, ADMP, etc.) techniques. It is shown that, at a temperature of 100 °C, the system under study remains thermally and chemically stable for up to 30 min. It was established using X-ray diffraction analysis that the heating time barely affects the X-ray characteristics of the system. Data on the aggregate states in specified temperature ranges were obtained with thermal analysis and determination of the melting point. The structures of the ammonium sulfamate-urea system with different component ratios were optimized within the density functional theory. The atom-centered density matrix propagation calculation of the ammonium sulfamate-urea system with different component ratios was performed at temperatures of 100, 300, and 500 K. Regardless of the component ratio, a regular increase in the potential energy variation (curve amplitude) with an increase in temperature from 100 to 500 K was found.

Imidazole derivatives have found wide application in organic and medicinal chemistry. In particular, benzimidazoles have proven biological activity as antiviral, antimicrobial, and antitumor agents. In this work, we experimentally and theoretically investigated N-Butyl-1H-benzimidazole. It has been shown that the presence of a butyl substituent in the N position does not significantly affect the conjugation and structural organization of benzimidazole. The optimized molecular parameters were performed by the DFT/B3LYP method with 6-311++G(d,p) basis set. This level of theory shows excellent concurrence with the experimental data. The non-covalent interactions that existed within our compound N-Butyl-1H-benzimidazole were also analyzed by the AIM, RDG, ELF, and LOL topological methods. The color shades of the ELF and LOL maps confirm the presence of bonding and non-bonding electrons in N-Butyl-1H-benzimidazole. From DFT calculations, various methods such as molecular electrostatic potential (MEP), Fukui functions, Mulliken atomic charges, and frontier molecular orbital (HOMO-LUMO) were characterized. Furthermore, UV-Vis absorption and natural bond orbital (NBO) analysis were calculated. It is shown that the experimental and theoretical spectra of N-Butyl-1H-benzimidazole have a peak at 248 nm; in addition, the experimental spectrum has a peak near 295 nm. The NBO method shows that the delocalization of the aσ-electron from σ (C1-C2) is distributed into antibonding σ* (C1-C6), σ* (C1-N26), and σ* (C6-H11), which leads to stabilization energies of 4.63, 0.86, and 2.42 KJ/mol, respectively. Spectroscopic investigations of N-Butyl-1H-benzimidazole were carried out experimentally and theoretically to find FTIR vibrational spectra.

This study aims to experimentally and theoretically examine the plant Aethionema sancakense , which was determined as a new species and whose essential oil and fatty acid compositions were characterized by GC/GC-MS technique. Linoleic acid (23.1%), α-humulene (19.8%), camphene (13.9%), and heptanal (9.7%) were found to be the major essential oil components of A. sancakense aerial part structures. The quantum chemical calculations of these four molecules that are very important to this plant were performed using the density functional method (DFT)/B3LYP with the 6-31 G (d, p) basis set in the ground state for the gas phase. The molecular structures, HOMO-LUMO energies, electronic properties, Fukui functions, and molecular electrostatic potential (MEP) surfaces of the major constituents of Aethionema sancakense essential oil were calculated and interpreted. Finally, the RDG-NCI analysis of these molecules was performed to determine the non-covalent interactions present within the molecules.

Soda lignin is a by-product of the soda process for producing cellulose from grassy raw materials. Since a method for the industrial processing of lignin of this type is still lacking, several research teams have been working on solving this problem. We first propose a modification of soda lignin with sulfamic acid over solid catalysts. As solid catalysts for lignin sulfation, modified carbon catalysts (with acid sites) and titanium and aluminum oxides have been used. In the elemental analysis, it is shown that the maximum sulfur content (16.5 wt%) was obtained with the Sibunit-4 ® catalyst oxidized at 400 °C. The incorporation of a sulfate group has been proven by the elemental analysis and Fourier-transform infrared spectroscopy. The molecular weight distribution has been examined by gel permeation chromatography. It has been demonstrated that the solid catalysts used in the sulfation process causes hydrolysis reactions and reduces the molecular weight and polydispersity index. It has been established by the thermal analysis that sulfated lignin is thermally stabile at temperatures of up to 200 °C. According to the atomic force microscopy data, the surface of the investigated film consists of particles with an average size of 50 nm. The characteristics of the initial and sulfated β-O-4 lignin model compounds have been calculated and recorded using the density functional theory.

Betulin is an important triterpenoid substance isolated from birch bark, which, together with its sulfates, exhibits important bioactive properties. We report on a newly developed method of betulin sulfation with sulfamic acid in pyridine in the presence of an Amberlyst ® 15 solid acid catalyst. It has been shown that this catalyst remains stable when being repeatedly (up to four cycles) used and ensures obtaining of sulfated betulin with a sulfur content of ~10%. The introduction of the sulfate group into the betulin molecule has been proven by Fourier-transform infrared, ultraviolet-visible, and nuclear magnetic resonance spectroscopy. The Fourier-transform infrared (FTIR) spectra contain absorption bands at 1249 and 835-841 cm -1 ; in the UV spectra, the peak intensity decreases; and, in the nuclear magnetic resonance (NMR) spectra, of betulin disulfate, carbons С3 and С28 are completely shifted to the weak-field region (to 88.21 and 67.32 ppm, respectively) with respect to betulin. Using the potentiometric titration method, the product of acidity constants K 1 and K 2 of a solution of the betulin disulfate H + form has been found to be 3.86 × 10 -6 ± 0.004. It has been demonstrated by the thermal analysis that betulin and the betulin disulfate sodium salt are stable at temperatures of up to 240 and 220 °C, respectively. The density functional theory method has been used to obtain data on the most stable conformations, molecular electrostatic potential, frontier molecular orbitals, and mulliken atomic charges of betulin and betulin disulfate and to calculate the spectral characteristics of initial and sulfated betulin, which agree well with the experimental data.

In this study, brass (Cu/Zn) reinforced polymer composites with different proportions of brass powders were fabricated. Different types of nuclear shielding parameters such as mass and linear attenuation coefficients, radiation protection efficiency, half and tenth value layers, and effective atomic number values were determined experimentally and theoretically in the energy range of 0.060-1.408 MeV in terms of gamma-ray shielding capabilities of fabricated polymer composites. A high Purity Germanium detector (HPGe) in conjunction with a Multi-Channel Analyzer (MCA) and twenty-two characteristic gamma-ray energies have been used in the experimental phase. In addition, the exposure and energy absorption buildup factors of reinforced Cu/Zn composites were calculated, and relative dose distribution values were computed to verify them. Proton mass stopping power (Ψ P ), proton projected range (Φ P ), alpha mass stopping power (Ψ A ), and alpha projected range (Φ A ) parameters, which indicate the interactions of the produced composites with charged particle radiation, were investigated. Fast neutron removal cross-section (Σ R ) results were determined to give an idea in terms of neutron shielding. According to the obtained results, it is reported that the CuZn20 coded sample's ability to attenuate gamma-ray and charged particle radiation is more efficient than that of other prepared composites. A CuZn05 coded sample was found to be more suitable for neutron shielding capability.

Sulfated cellulose derivatives are biologically active substances with anticoagulant properties. In this study, a new sulfated diethylaminoethyl (DEAE)-cellulose derivative has been obtained. The effect of a solvent on the sulfation process has been investigated. It is shown that 1,4-dioxane is the most effective solvent, which ensures the highest sulfur content in DEAE-cellulose sulfate under sulfamic acid sulfation. The processes of sulfamic acid sulfation in the presence of urea in 1,4-dioxane and in a deep eutectic solvent representing a mixture of sulfamic acid and urea have been compared. It is demonstrated that the use of 1,4-dioxane yields the sulfated product with a higher sulfur content. The obtained sulfated DEAE-cellulose derivatives have been analyzed by Fourier transform infrared spectroscopy, X-ray diffractometry, and scanning electron and atomic force microscopy, and the degree of their polymerization has been determined. The introduction of a sulfate group has been confirmed by the Fourier transform infrared spectroscopy data; the absorption bands corresponding to sulfate groups have been observed in the ranges of 1247-1256 and 809-816 cm -1 . It is shown that the use of a deep eutectic solvent leads to the side carbamation reactions. Amorphization of DEAE-cellulose during sulfation has been demonstrated using X-ray diffractometry. The geometric structure of a molecule in the ground state has been calculated using the density functional theory with the B3LYP/6-31G(d, p) basis set. The reactive areas of DEAE-cellulose and its sulfated derivatives have been analyzed using molecular electrostatic potential maps. The thermodynamic parameters (heat capacity, entropy, and enthalpy) of the target sulfation products have been determined. The HOMO-LUMO energy gap, Mulliken atomic charges, and electron density topology of the title compound have been calculated within the atoms in molecule theory., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

The synthesis of guar gum sulfates by a complex of sulfur trioxide with 1,4-dioxane was studied. The influence of temperature, process duration, and the volume of chlorosulfonic acid on the degree of substitution of guar gum sulfates was studied. The sulfation process has been optimized using the Box-Behnken design. It was shown that the optimal conditions for sulfation of guar gum with a complex of sulfur trioxide-1.4-dioxane: temperature 60 °C, duration 2.9 h, and a volume of chlorosulfonic acid of 3.1 ml. Sulfate groups embedding into the structure of guar gum was confirmed by elemental analysis and FTIR. The initial and sulfated guar gum were also characterized by methods: X-ray diffraction, scanning electron microscopy, and gel permeation chromatography. Using X-ray diffraction, it was shown that amorphization of guar gum occurs during sulfation. Using scanning electron microscopy, it was shown that the morphology of guar gum changes in the process of sulfation. Using gel permeation chromatography, it was shown in the process of guar gum sulfation by a complex of sulfur trioxide with 1,4-dioxane, the molecular weight decreases from 600 to 176 kDa. The geometric parameters of all complexes were carried out by using the DFT/B3PW91 method with a 6-31 + G (d,p) basis set. These structures are optimized to predict the important properties of a theme. MEP with contour map has been performed to obtain the electronic properties. Frontier molecular orbital HOMO-LUMO orbital diagram has been obtained for different energy levels and their band gap energies have been computed.

This study aims to experimentally and theoretically examine the nature and energy of intermolecular bond interactions between thiourea and water molecules using natural bond orbital (NBO), non-linear optical (NLO), atoms in molecules (AIM), and reduced density gradient (RDG) analyses based on the quantum chemical approach and spectroscopic analysis on X-ray and FTIR. Geometry optimizations of Thio-(H 2 O) 1-5 complexes were carried out in the gas phase by B3LYP/6-311++G(d,p) level of density functional theory. The nature of the molecular interactions between the water and thiourea through hydrogen bonding has been investigated using RDG and AIM methods. NBO analysis shows that the Thio-(H 2 O) 5 complex has higher stabilization energy values than the other complexes. The non-linear optical properties, such as dipole moment (μ), the polarizability (α 0 ), and the first hyperpolarizability (β tot ), and thermodynamic functions, such as entropy (S), specific heat capacity (C v ), and thermal energy (E), were calculated using the same method. It was observed that thermodynamic parameters, polarizability, and the first hyperpolarizability increased with the number of water molecules. X-ray diffraction analysis confirmed that thiourea is single crystal, and the thiourea/water complexes are crystalline in nature. Besides, the infrared spectrum shows the existence of water molecules and it is used to get details of the structure of the complex.

Purpose: The aim was to evaluate the treatment outcomes and prognostic characteristics of patients with early-stage glottic laryngeal carcinoma who underwent radical radiotherapy (RT) with different techniques., Patients and Methods: Radiotherapy was applied using the 2D conventional technique between 1991 and 2004 (130 patients), 3DCRT until 2014 (125 patients), and by VMAT until January 2017 (44 patients). Clinical T stages were 38 (12.7%) for Tis, 209 (69.9%) for T1, and 52 (17.4%) for T2. Radiotherapy technique and energy, anterior commissure involvement, and stage were analyzed as prognostic factors., Results: The median total dose was 66 (50-70) Gy, and median follow-up time was 72 (3-288) months; 5-year disease-specific survival (DSS) rates were 95.8%, 95.5%, and 88.6%, respectively, in Tis, T1, and T2 stages. In multivariate analyses, anterior commissure involvement was found significant for all survival and local control rates. The patients treated with VMAT technique had better local control and DSS rates. However, these results were not statistically significant., Conclusion: In early-stage laryngeal carcinomas, radical RT is a function sparing and effective treatment modality, regardless of treatment techniques., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2019 Oguz Cetinayak et al.)

This study evaluated the effects of lateral temporal bone resection (LTBR) on local tumour control in patients with locally advanced parotid gland tumours. The medical records of seven patients treated with radical parotidectomy combined with LTBR for locally advanced primary parotid tumour at the Otolaryngology Department of Dokuz Eylul University between January 1995 and December 2016 were retrospectively evaluated. Demographic variables, tumour characteristics, treatment properties, postoperative complications, follow-up durations and local, regional and distant recurrences were analysed. Before referral to our clinic, four patients had de novo primary parotid tumours, and three patients had a recurrence of primary parotid tumours. The histopathologic diagnoses were squamous cell carcinoma in two patients, and adenosquamous carcinoma, malignant myoepithelial carcinoma, adenocarcinoma, adenoid cystic carcinoma and spindle cell sarcoma in the other patients. During the follow-up period, one patient died due to postoperative pulmonary embolism in the first month, and four patients died due to distant metastasis without local or regional recurrences. LTBR combined with radical parotidectomy in locally advanced primary malignant parotid gland tumours is a feasible surgical technique for local tumour control. However, the most common cause of death in these cases is distant metastases, despite appropriate resection., Competing Interests: Conflict of interestThe authors have no funding, financial relationships or conflict of interest to disclose., (© Association of Otolaryngologists of India 2018.)

Pagetoid spread, is used to define intraepithelial spread of cancer cells, when a massive carcinoma is identified beneath the basal membrane. There are only few reports of pagetoid spread at the head and neck region. Herein a 74 year old male patient with bilateral transglottic laryngeal high grade malignant epithelial tumor with pagetoid spread is presented. The tumor was located at the submucosa and there was spread of the CK7 and CK19 positive tumor cells into the non neoplastic mucosa, which was CK5/6 positive, sparing the basement membrane, creating a typical pagetoid pattern. Radiographic and positron emission tomography scan examination of the patient was unremarkable at presentation other than the laryngeal and neck lesions; but extensive systemic metastasis developed at 6 months following operation. To the best of our knowledge no epithelial malignancy with pagetoid spread was described at the larynx. Pagetoid spread may be a hallmark of very aggressive behavior in laryngeal carcinoma.

Objective: Tumor-stroma proportion of tumor has been presented as a prognostic factor in some types of adenocarcinomas, but there is no information about squamous cell carcinomas and laryngeal carcinomas., Material and Method: Five digital images of the tumor sections were obtained from 85 laryngeal carcinomas. Proportion of epithelial tumor component and stroma were measured by a software tool, allowing the pathologists to mark 205.6 μm2 blocks on areas as carcinomatous/stromal, by clicking at the image. Totally, 3.451 mm2 tumor areas have been marked to 16.785 small square blocks for each case., Results: Median follow up was 48 months (range 3-194). The mean tumor-stroma proportion was 48.63+18.18. There was no difference for tumor-stroma proportion when tumor location, grade, stage and perinodal invasion were considered. Although the following results were statistically insignificant, the mean tumor-stroma proportion was the lowest (37.46±12.49) for subglottic carcinomas, and it was 52.41±37.47, 50.86+19.84 and 44.56±16.91 for supraglottic, transglottic and glottic cases. The tumor-stroma proportion was lowest in cases with perinodal invasion and the highest in cases without lymph node metastasis (44.72±20.23, 47.77±17.37, 50.05±17.34). Tumor-stroma proportion was higher in the basaloid subtype compared with the classical squamous cell carcinoma (53.76±14.70 and 48.63±18.38 respectively). The overall and disease-free survival analysis did not reveal significance for tumor-stroma proportion (p=0.08, p=0.38). Only pathological stage was an independent factor for overall survival (p=0.008)., Conclusion: This is the first series investigating tumor-stroma proportion as a prognostic marker in laryngeal carcinomas proposing a new method, but the findings do not support tumor-stroma proportion as a prognostic marker.

Background: Laparoscopic donor nephrectomy has gained popularity throughout the world recently. The more centers became experienced the more this technique began to be used, even in extreme cases. Kidneys with multiple renal arteries are one of the difficult cases for laparoscopic donor nephrectomy., Patients and Method: Thirty living laparoscopic donor nephrectomies have been performed between January 2001 and December 2002. Twenty-three of them had single and seven kidneys had multiple renal arteries. Single (SA) and multiple (MA) artery groups were statistically similar in terms of donor age, rate of received right kidneys and serum creatinine clearance of the donors., Results: The mean duration of the donor surgery was 225 min and 240 min in SA and MA groups. In the SA and MA groups, the mean warm and cold ischemia times were statistically similar. Laparoscopic nephrectomy was converted to open procedure in five and one donors, in the SA and MA artery groups, respectively. Intraoperative bleeding (single artery: 4, multiple arteries: 1) was the most common cause for conversion. Postoperative urinary complications were seen in four and one patients, in the SA and MA groups, respectively. Lengths of hospital stay of the donors were similar in both groups. Serum creatinine levels of the patients on seventh, 30th, 90th days, and 1 year were found to be statistically similar in both groups., Conclusion: Laparoscopic donor nephrectomy was found to be a safe procedure in the donors with multiple renal arteries by the experienced surgical teams, as much as in donors with single arteries.

Objective: Due to organ shortage in renal transplantation, many transplant centers attempt to increase the donor pool. Non-heart-beating donors seem to be a promising alternative., Patients and Methods: We performed 14 renal transplantations from 8 non-heart-beating donors. 2, 1, 3 and 2 donors were from groups 1, 2, 3 and 4, respectively, according to Maastricht classification., Results: In 6 of the patients' warm ischemia time was over 30 minutes. Three of them had primary non-function. In 6 patients delayed graft function was seen. The remaining 5 kidneys functioned immediately. Two patients whose kidney functioned returned to hemodialysis in the I I and 13th months after their transplantations. One of the patients with primary non-function died. 9 kidneys function well in their follow-up period between 5-111 months. 1 and 5-year graft survival rates were 69.8 and 61.1 percent, respectively. The mean graft survival time is 69.9 +/- 14.5 months., Conclusion: Despite the high primary non-function rate, we think that non-heart-beating donors especially in Maastricht classification 3 and 4 should be used due to dramatic shortage of organs.

Background: Due to organ shortage, it is not easy to find an ideal donor in renal transplantation. To enhance donor pool, marginal donors can be acceptable even in living renal transplantations. We compared optimal and marginal donor transplantations in terms of graft and patient survival., Methods: We performed 32 living related renal transplantations, 11 of which were from marginal donors, from January 1999 to December 2000. Recipients from optimal and marginal donors were compared in terms of renal function, acute tubular necrosis (ATN) and acute rejection (AR) rates., Results: Although mean serum creatinine level in the seventh day was found to be higher in the recipients from marginal donors (1,88 mg/dl vs. 2,51 mg/dl); it did not reach to a statistical difference (p = 0.1). Serum creatinine levels after thirtieth day, ATN and AR rates were statistically similar in both groups, as well. In optimal and marginal groups, 3-year graft survival rates were found to be 85 and 72 percent respectively (p = 0.72). 3-year patient survival rates were also found to be similar in both groups (90% vs. 91%) (p = 0.91)., Conclusion: Functional and survival results in the transplantations from marginal donors were as good as from optimal donors. So, we thought that marginal donors could be used safely with a good preoperative evaluation to increase donor pool.