Promising Outcomes in Acromegaly Patients Receiving CyberKnife Stereotactic Hypofractionated Radiotherapy.

Background: The primary treatment for patients with acromegaly has traditionally been transsphenoidal surgery, with decreasing reliance on radiotherapy (RT) due to advancements in pharmacotherapy (PT). Despite these advancements, a substantial portion of patients still face persistent acromegaly, necessitating novel treatment approaches. This study investigates the role of CyberKnife Stereotactic Hypofractionated Radiotherapy (CK-HFRT) in persistent acromegaly.

Hydrophobic surface modification and characterization of melamine foam.

Superhydrophobic and oleophilic modification of commercial acoustic melamine foam (MF) was made in this study. The modification was carried out with chitosan (CHI) and silica particles (SiO), by using both a layer-by-layer-like approach (LbL) and dip coating technique. Subsequently, 1-octadecanethiol was used as a secondary modification agent.

Synthesis optimization of ZrO nanostructures for photocatalytic applications.

This study aims to optimize the synthesis of semiconductor zirconia (ZrO) nanoparticles for future photocatalytic applications in degradation of pollutants in wastewater under ultraviolet (UV) light. The synthesis procedure of ZrO nanoparticles was optimized by examining the effects of synthesis methods (ultrasound-assisted, hydrothermal method in an autoclave and conventional precipitation), reaction time (2, 6, 10, and 18 h), ambient pH (3, 7, 10, 13), and surfactant type (anionic, cationic, and non-ionic), on the particle size and crystal phase of the nanomaterial. The characterization of the synthesized samples was performed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDS), high-contrast transmission electron microscopy (HR-TEM), and transmission electron microscope (TEM) analysis.

A New Family of Layered Metal-Organic Semiconductors: Cu/V-Organophosphonates.

Herein, we report the design and synthesis of a layered redox-active, antiferromagnetic metal organic semiconductor crystals with the chemical formula [Cu(H O) V(µ-O)(PPA) ] (where PPA is phenylphosphonate). The crystal structure of [Cu(H O) V(µ-O)(PPA) ] shows that the metal phosphonate layers are separated by phenyl groups of the phenyl phosphonate linker. Tauc plotting of diffuse reflectance spectra indicates that [Cu(H O) V(µ-O)(PPA) ] has an indirect band gap of 2.

A dosimetric comparison for SBRT plans of localized prostate cancer between Cyberknife and Varian Truebeam STX device.

As the Stereotactic Body Radiotherapy (SBRT) approach began to increase in treating patients with localized prostate cancer, it became necessary to investigate which methods used in practice were better. The aim of this study is to perform a dosimetric comparison of the advantages and disadvantages of SBRT treatments for localized prostate cancer delivered by CyberKnife (CK) and Varian Truebeam STX (FF and FFF). Seventeen intermediate and high-risk patients with localized prostate cancer were included in the study.

Enhancement of dispersion stability of inorganic additives via poly(sodium-4-styrenesulfonate) treatment geared to hydrogel applications.

This study reports the preparation of poly(sodium-4-styrene sulfonate) (PSS) treated bentonite and clinoptilolite to prevent the agglomeration and sedimentation of these inorganic fillers during the preparation of hydrogel. For this purpose PSS treated fillers were prepared by using various techniques (dip and dry, hydrothermal, one-step ball milling and ultrasonication methods). The most suitable technique for preparing these PSS treated inorganic fillers (abbreviated as BP-dip and CP-dip) was the dip and dry method.

Detection of bacteria using antimicrobial polymer derived via ring-opening metathesis (romp) pathway.

There is growing interest in the detection of bacteria in consumables, for example, in the food and water sectors. In this study, the aim was to produce a polymer-based bacteria biosensor via ROMP (ring opening metathesis polymerization). In the first part of the study, block and random copolymers were synthesized, and their biocidal activities were tested on the glass surface.

Investigation of approaches for internal target volume definition using 4-dimensional computed tomography in stereotactic body radiotherapy of lung cancer.

The present study was undertaken to investigate the suitability of alternative internal target volume (ITV) delineation strategies based on maximum intensity projection (MIP), average intensity projection (AIP), 2 extreme phases and 4 phases images relative to the ITV in stereotactic body radiation therapy (SBRT) for lung cancer. The 4-dimensional computed tomography (4DCT) data of 15 lung cancer patients treated with SBRT in our clinic were used. Five different ITVs were generated as follows: merging GTVs from 10 phases (ITV); merging GTVs from 2 extreme phases (0%, 50%) (ITV); merging GTVs from 4 phases (0%, 20%, 50%, and 70%) (ITV); delineating GTV on MIP (ITV), and delineating GTV on AIP (ITV).

A column generation heuristic for VMAT planning with adaptive CVaR constraints.

In this study we develop an efficient computational procedure that generates medically acceptable treatment plans for volumetric modulated arc therapy with constant gantry speed. Our proposed method is a column generation heuristic based on a mixed integer linear programming model, where the objective function contains minimization of total monitor unit of the treatment plan and dose-volume requirements are included as conditional value-at-risk constraints. Our heuristic generates a full treatment arc for the restricted master problem and calibrates the right hand side parameters of the conditional value-at-risk constraints in the first phase.

Ventriculoperitoneal Shunting in Alobar Holoprosencephaly: Does it Work Even When Patient Has No Sign of Raised Intracranial Pressure?

Holoprosencephaly (HPE) is a developmental anomaly of forebrain characterized by a failure of division of the embryonic forebrain into hemispheres. It is associated with a set of facial anomalies at a rate of 80%. Survival rate, particularly in alobar HPE, is quite low.

Patient-specific quality assurance for intracranial cases in robotic radiosurgery system.

Purpose: The purpose of this study was to perform pretreatment patient-specific quality assurance (QA) for intracranial irradiation using CyberKnife with an ion chamber.

Methods: Twenty-five intracranial plans created using the ray-tracing algorithm were used for this study. Computed tomography (CT) images of the water-equivalent RW3 slab phantom with PinPoint ionization chamber were acquired with 1-mm slice thickness and transferred to the MultiPlan treatment planning system (TPS).

Unilateral Vision Loss without Ophthalmoplegia as a Rare Complication of Spinal Surgery.

Postoperative visual loss is an extremely rare complication of nonocular surgery. The most common causes are ischemic optic neuropathy, central retinal artery occlusion, and cerebral ischemia. Acute visual loss after spinal surgery is even rarer.

Conventionally Fractionationed Volumetric Arc Therapy versus Hypofractionated Stereotactic Body Radiotherapy: Quality of Life, Side Effects, and Prostate-Specific Antigen Kinetics in Localized Prostate Cancer.

Objectives: To compare conventionally fractionationed volumetric arc therapy (VMAT) and hypofractionated stereotactic body radiotherapy (SBRT) modalities in terms of prostate-specific antigen (PSA) kinetics, toxicity, and quality of life (QOL) in patients with localized prostate cancer.

Methods: Patients received radical radiotherapy as either 33.5 Gy/5 fr for SBRT or 75.

Clinical Results of Median Corpectomy in Cervical Spondylotic Patients with Myelopathy.

Aim: To determine the factors in choosing the right surgical technique for patients with cervical spondylotic myelopathy.

Material And Methods: 60 patients were operated with anterior median corpectomy and anterior fusion for cervical myelopathy in Ankara Atatürk Education and Research Hospital between the years 2006-2011. All data were obtained from patient files retrospectively.

Photon atomic parameters of nonessential amino acids for radiotherapy and diagnostics.

The total mass attenuation coefficients (μ t ) (cm(2)/g) and atomic, molecular, and electronic effective cross sections have been calculated for nonessential amino acids that contain H, C, N, and O such as tyrosine, aspartate, glutamine, alanine, asparagine, aspartic acid, cysteine, and glycine in the wide energy region 0.015-15 MeV. The variations with energy of total mass attenuation coefficients and atomic, molecular, and electronic cross sections are shown for all photon interactions.

A comparison of TPS and different measurement techniques in small-field electron beams.

In recent years, small-field electron beams have been used for the treatment of superficial lesions, which requires small circular fields. However, when using very small electron fields, some significant dosimetric problems may occur. In this study, dose distributions and outputs of circular fields with dimensions of 5cm and smaller, for nominal energies of 6, 9, and 15MeV from the Siemens ONCOR Linac, were measured and compared with data from a treatment planning system using the pencil-beam algorithm in electron beam calculations.

Energy absorption and exposure buildup factors of essential amino acids.

The effective atomic number and effective electron density in amino acids are of significant interest due to their use in various applications. The energy absorption buildup factors, exposure buildup factors, effective atomic numbers, and electron densities of essential amino acids such as Leucine (C6H13NO2), Lysine (C6H14N2O2), Methionine (C5H11NO2S), Phenylalanine (C9H11NO2), Threonine (C4H9NO3), Tryptophan (C11H12N2O2), Valine (C5H11NO2), Arginine (C6H14N4O2), and Histidine (C6H9N3O2) were determined theoretically in the energy range 0.015-15 MeV.

Comparison effects and dielectric properties of different dose methylene-blue-doped hydrogels.

The dielectric properties of methylene blue (MB)-doped hydrogels were investigated by impedance spectroscopy. The real part (ε') and the imaginary part (ε") of the complex dielectric constant and the energy loss tangent/dissipation factor (tan δ) were measured in the frequency range of 10 Hz to 100 MHz at room temperature for pH 5.5 value.

Differential expression of long non-coding RNAs during genotoxic stress-induced apoptosis in HeLa and MCF-7 cells.

Long non-coding RNAs (lncRNAs) are emerging as new players in cancer as they are implicated in diverse biological processes and aberrantly expressed in a variety of human cancers. No data are available on their function under genotoxic stress-induced apoptosis. In this work, we assessed the behavior of some candidate lncRNAs (HOTAIR, MALAT1, TUG1, lincRNA-p21, GAS5, MEG3, PANDA, UCA1, ANRIL, and CCND1) during DNA damage-induced cell death in HeLa and caspase-3-deficient MCF-7 cells using bleomycin (BLM) and γ-radiation to induce DNA damage.

Surface dose and build-up region measurements with wedge filters for 6 and 18 MV photon beams.

Purpose: High-energy photons are most commonly used in radiotherapy to treat cancer. Wedge filters are required to obtain homogeneous dose distribution in the patient. Different wedge filter types create different surface doses.

The effect of oblique electron beams to the surface dose under the bolus.

The aim of this study is to determine the effect of bolus to the surface dose in oblique electron incidences. Irradiations with 4.5, 6, 7.

Surface dose measurements with GafChromic EBT film for 6 and 18MV photon beams.

The aim of this study was to determine the surface doses using GafChromic EBT films and compare them with plane-parallel ionization chamber measurements for 6 and 18 MV high energy photon beams. The measurements were made in a water equivalent solid phantom in the build-up region of the 6 and 18MV photon beams at 100 cm SSD for various field sizes. Markus type plane-parallel ion chamber with fixed-separation between collecting electrodes was used to measure the percent depth doses.

Toxic-dose warfarin-induced apoptosis and its enhancement by gamma ionizing radiation in leukemia K562 and HL-60 cells is not mediated by induction of oxidative stress.

The purpose of this study was to test the hypothesis that warfarin may enhance free radical production and oxidative damage on cancer cells. We examined the possible concentration-dependent effect of warfarin on cytotoxicity with respect to oxidative stress on leukemia cell lines (K562 and HL-60) and normal human peripheral blood mononuclear cells (PBMC). Gamma radiation was used as a positive control agent for oxidative stress.

Effect of field placement errors on dose at junction between divergence matching and half-beam block techniques in craniospinal irradiation.

Purpose: In craniospinal irradiation, both overlapping and gapping between the cranial and upper spinal field may occur due to patient's daily position (setup). This can cause dose inhomogeneities at the craniospinal junction. In this study we tried to find out possible dose changes at the craniospinal junction due to setup mistakes.

Do collimator angle setup errors cause dose inhomogeneity at the junction zone during craniospinal irradiation? A phantom study.

Purpose: Craniospinal irradiation (CSI) has some geometric uncertainties, especially at the junction zone. In this study we tried to evaluate how possible random setup errors of the collimator angle may contribute to these uncertainties.

Materials And Methods: Cranial and spinal fields were drawn on RW3 solid water phantom in accordance with the divergence matching technique (DMT).