67 research outputs found
Effect of fluoride sodium mouthwash solutions on cpTI: evaluation of physicochemical properties
Immediate loading implants with mandibular overdenture: a 48-month prospective follow-up study
Hemodinâmica de diferentes frações inspiradas de oxigênio em cães submetidos à infusão contínua de propofol sob ventilação espontânea
Hipofiz Cerrahisi Yapilan Akromegalik Hastalarda Hava Yolu Yönetiminin Retrospektif Degerlendirilmesi
Objective: Acromegaly is an endocrinological disease that has morbidity and mortality characterised by high levels of growth hormone (GH) and insülin like growth factor-I (IGF-I). Typical big nose and lips, macroglossia, enlargement of mandible may be observed due to acral changes. Hypertrophy of pharynx, larynx, tonsils, vocal cords, mucosa and soft tissue may occur in acromegaly. Due to the characteristics of acromegaly, difficult mask ventilation and airway management might be anticipated in these patients. The purpose of this study was to document the challenges and methods used in airway management in acromegaly patients undergoing transsphenoidal pituitary surgery and to compare the success rates of these methods. Methods: The perioperative records of 120 patients that underwent transsphenoidal resection of pituitary adenoma at our university hospital between 2003-2013 were reviewed. Results: Among the patients studied, difficulty with intubation was encountered in %10 of patients which is consistent with literature. Patients whose laryngoscopy was challenging were intubated by changing blade, application of external laryngeal pressure or using a guide. One patient was intubated using LMA FastrachTM. Obstructive sleep apnea syndrome (OSAS) is a frequent comorbidity in acromegalic patients and this co-occurrence is also associated with difficult intubation. Conclusion: Significant correlation was observed between Mallampati gradings and incidence of difficult endotracheal intubation. Also obstructive sleep apnea syndrome (OSAS) which is very frequent in acromegalic patients is also associated with difficulty in airway management. We think that induction of anesthesia should be attempted after taking precautions to overcome difficult airway management in these patients. © Copyright Association of Anesthesiologists and Reanimation Specialists.Scopu
Activation of the AKT and STAT3 pathways and prolonged survival by a mutant EGFR in human lung cancer cells
To clarify the pathogenic and biological significance of EGFR mutations in lung cancer, we compared the status of ERBB family receptors, their downstream signal transductions and biological phenotypes between lung cancer cell lines with mutant and wild type EGFR. We initially analyzed expression and phosphorylation of ERBB family receptors and their major downstream proteins, AKT, p44/42 MAPK and STAT3, in a series of lung cancer cell lines with or without EGFR mutation. The expression levels of EGFR as well as of ERBB2 and ERBB3 proteins in cells with EGFR mutation tended to be higher than those in cells with wild type EGFR. There was no difference in stability between mutant and wild type EGFR proteins. EGF induced phosphorylation of EGFR, AKT, p44/42 MAPK and STAT3 to various extents, but the level of induction was not associated with the existence of EGFR mutation. These results implied that the activation of AKT, p44/42 MAPK and STAT3 signaling transmitted by EGFR would be critical for the growth and survival of lung cancer cells, but specific features of mutant EGFR in lung cancer cells was not discriminated by these approaches. We therefore performed transfection studies using PC-13 cells with no detectable endogenous EGFR expression. Exogenous expression of wild type and mutant EGFR (delE746-A750) in the cells revealed that only in the mutant EGFR transfected cells, EGFR itself as well as AKT and STAT3 were highly phosphorylated after 24 h of serum deprivation. The survival time of mutant EGFR transfected cells was prolonged under serum-free culture conditions, but not under standard culture conditions with 10% serum. These results suggest that cells with a mutant EGFR survive through the activation of the AKT and/or STAT3 pathways, even in low EGF microenvironments. This specific property due to EGFR mutation could be an important step of multistage lung cancer progression. © 2006 Elsevier Ireland Ltd. All rights reserved
Regional clinical and biochemical differences among patients with primary hyperparathyroidism
Background: Environmental habitat may play a role in clinical disparities of primary hyperparathyroidism (pHPT) patients. Aims: To compare preoperative clinical symptoms and associated conditions and surgical findings in patients with pHPT, living in different geographical regions from the Black Sea, Mediterranean and Anatolia regions. Study Design: Retrospective, clinical-based multi-centric study of 694 patients with pHPT. Methods: Patients from 23 centers and 8 different geographical regions were included. Data related to baseline demographics, clinical, pathologic and treatment characteristics of 8 regions were collected and included age, gender, residential data, symptoms, history of fracture, existence of brown tumor, serum total Ca and p levels, serum parathormone (PTH) levels, serum 25-OH vitamin D levels, bone mineral density, size of the resected abnormal parathyroid gland(s), histology, as well as the presence of ectopia, presence of dual adenoma, and multiple endocrine neoplasia (MEN)- or familial-related disease. Results: The median age was 54. Asymptomatic patient rate was 25%. The median PTH level was 232 pg/mL and serum total Ca was 11.4 mg/dL. Eighty-seven percent of patients had an adenoma and 90% of these had a single adenoma. Hyperplasia was detected in 79 patients and cancer in 9 patients. The median adenoma size was 16 mm. Significant parameters differing between regions were preoperative symptoms, serum Ca and p levels, and adenoma size. All patients from South-East Anatolia were symptomatic, while the lowest p values were reported from East Anatolia and the largest adenoma size, as well as highest Ca levels, were from Bulgaria. Conclusion: Habitat conditions vary between geographical regions. This affects the clinicopathological features of patients with pHPT. © 2017 by Trakya University Faculty of Medicine/The Balkan Medical Journal published by Galenos Publishing House
Differentiating the natural and man-made terraces of Lake Van, Eastern Anatolia, utilizing earth science methods
The Fertile Crescent of the Middle East region, embracing Syria, eastern Turkey and Iraq, marks the region where settled agriculture began, and where the landscape has been shaped for millennia by human activities. The lacustrine and fluvial terraces of the Late Pleistocene and Holocene Eras are common geomorphic features in many areas around Lake Van in eastern Turkey, being sustainably used since the Urartian Period (800-400 years bc). Fluctuations in the water levels of Lake Van have resulted in the development of widely distributed natural terraces around the Lake. The undulating slopes of these terraces have limited their cultivation, however, leading people to reconstruct terraces as a means for utilizing particular production sites, as anthroscapes (this concept is generally confined to situations where marked differences or deviations from the normal, natural landscapes are attributable to effects/shaping by humans). The region exhibits semiarid climatic conditions and a short crop-growing season, currently being under the threat of land degradation. Recent mismanagement of these lands as a result of increasing population pressures has led to the degradation of both the natural and the man-made terraces. Thus, there is an urgent need to conserve and understand the indigenous management and soil quality attributes of these man-made terraces. To this end, this study examined soil profiles and analysed soil samples for their chemical, physical and mineralogical characteristics, in order to determine the human effects of leaching and/or accumulation. These analyses revealed significant differences between the physical, chemical, microbiological and mineralogical properties of the man-made/reworked terraces and natural terraces under essentially similar parent materials and environment, thereby providing clues as to the sustainable management of these land surfaces in eastern Turkey. The approaches used in this study provide useful evidence for attempting to explain the historical evolution of land use in similar environments elsewhere, as well as the significance of terraces in combating coastal erosion in lake environments. © Journal compilation © 2008 Blackwell Publishing Asia Pty Ltd
Effect of Sm(3+)and Mn2+ incorporation on the structure and luminescence characteristics of Zn2SiO4 phosphor
To evaluate the dopant effect precisely, X-ray diffraction (XRD) for structural, scanning electron microscopy (SEM) with energy dispersive x-ray spectroscopy (EDS) analysis for morphological, photoluminescence (PL) and thermoluminescence (TL) characteristics of un-doped, 2.0 mol% Sm3+ doped and 2.0 mol% Sm3+;x mol% Mn2+ (x = 0.5, 1.0, 2.0, 4.0) doped Zn2SiO4 phosphors were tested. PL mechanisms of excitation and emission were discussed together with data on the structure and morphology of the samples. The beta doses from 0.1 to 500 Gy with various steps were applied to observe the glow curve readouts after 200 degrees C preheat at a linear heating rate of 2 degrees C/s from RT to 500 degrees C. Zn2SiO4:2.0%Sm3+;0.5%Mn2+ was chosen for further analysis due to having both the most PL and TL peak area. Various heating rate method was used to determine the kinetic parameters as well as initial rise with T-M-T-stop analysis and computerized glow curve deconvolution methods.Research Fund of Cukurova University, Turkey [FBA2019-11318, FAY-2015-435]All authors thank Dr. M. Ayvacikli and Prof. Dr. N. Can for their support on XRD and PL evaluations. Z.G. Portakal-Ucar would like to thank Dr. J.M. Kalita and Dr. G.S. Polymeris for the valuable discussions on the TL results. The current study is financially supported by the Research Fund of Cukurova University, Turkey (Project Numbers: FBA2019-11318 and FAY-2015-435)
Assessing the impact of azadirachtin application to soil on urease activity and its kinetic parameters
The kinetic parameters of soil urease have attracted considerable attention; however, little information is available on its kinetic parameters and behaviors in response to azadirachtin application to the soil. A short (14-day) field experiment was conducted using Albic Luvisol soil (loam texture; pH 6.70; electrical conductivity 0.81 dS m-1; CaCO3 content 0.04%; total organic carbon 0.99%) as the experimental soil in the Perm region of the Russian Federation to investigate the effects of different azadirachtin application doses on soil urease activity and its kinetic behaviors. The results showed that the highest urease activity was found under high azadirachtin application doses (0.6 L ha-1) compared to the control (0 L ha-1), recommended (0.3 L ha-1), and low (0.15 L ha-1) azadirachtin application doses at all different incubation times (1, 2, 3, 6, and 12 h). Soil urease enzymes exhibited typical Michaelis-Menten kinetic behaviors; high azadirachtin application doses increased the substrate affinity constant (KM) and decreased the maximum reaction rates (Vmax) of soil urease. As compared to the control azadirachtin application dose, the low azadirachtin application dose increased the Vmax of soil urease; however, with low and recommended application doses, the Vmax of soil urease decreased. Overall, in this study, all azadirachtin application doses were effective in influencing the kinetic behavior of urease in Albic Luvisol. © TÜBİTAK
Thermoluminescence behavior of Sm3+ activated ZnB2O4 phosphors synthesized using low temperature chemical synthesis method
This study is mainly centered on thermoluminescence (TL) behavior under beta excitation at room temperature (RT) of Sm3+ activated ZnB2O4 phosphors synthesized by low temperature chemical synthesis method. The prepared phosphors were characterized by the X-ray powder diffraction (XRD) method. The effects of dopant concentration, beta radiation dose (0.115–69 Gy) and heating rate (0.5–10 °C/s) on TL intensity of Sm3+ doped ZnB2O4 phosphors and reproducibility are investigated using a lexsyg smart TL/OSL reader system. The activation energy values, E obtained from the analysis of the TL glow curve were calculated with initial rise (IR) method and peak shape (PS) method over the deconvoluted glow curves. The Ea–Tstop and CGCD methods indicated that the glow curve of this phosphor is the superposition of at least six components, which were called to as P1–P6, in the temperature range between RT and 400 °C. The results reveal that 2% Sm3+ doped ZnB2O4 gives optimum TL response, the relative intensity of the glow peak increases linearly with increase of beta dose and, the peaks of TL glow curves shift towards the higher temperature side with increase in heating rate as the total area under the glow peak remains the same. The maximum variation of reproducibility for ten successive irradiation cycles of 20.7 Gy is less than 3% from the average value and the sample doped 2% Sm3+ shows a good stability for the reusability. Additionally, the results obtained from IR and PS methods indicates that the complex glow curve is composed of six distinguishable peaks. © 2018 Elsevier B.V
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