Turkish validity and reliability of the lifestyle questionnaire related to cancer.

OBJECTIVE: The aim of this study was to adapt the lifestyle questionnaire related to cancer in Turkish and investigate its validity and reliability. METHODS: This methodological study was conducted on 1,196 participants. Cronbach's α was used to assess validity and reliability. The internal consistency was evaluated using item-total correlation. RESULTS: The normed chi-square in this study was 5.87. The root mean square error of approximation was calculated as 0.051. The comparative fit index and the Tucker-Lewis Index were 0.83 and 0.81, respectively. The split-half method was used to test the reliability of the scale (Part 1 Cronbach's α: 0.826, Part 2 Cronbach's α: 0.812, and Adjusted Cronbach's α: 0.881). CONCLUSION: The Turkish version of lifestyle questionnaire related to cancer (8 subscales, 41 items) is a reliable and valid measure to evaluate lifestyle behaviors related to cancer in adults.

Turkish validity and reliability of the lifestyle questionnaire related to cancer

SUMMARY OBJECTIVE: The aim of this study was to adapt the lifestyle questionnaire related to cancer in Turkish and investigate its validity and reliability. METHODS: This methodological study was conducted on 1,196 participants. Cronbach's α was used to assess validity and reliability. The internal consistency was evaluated using item-total correlation. RESULTS: The normed chi-square in this study was 5.87. The root mean square error of approximation was calculated as 0.051. The comparative fit index and the Tucker-Lewis Index were 0.83 and 0.81, respectively. The split-half method was used to test the reliability of the scale (Part 1 Cronbach's α: 0.826, Part 2 Cronbach's α: 0.812, and Adjusted Cronbach's α: 0.881). CONCLUSION: The Turkish version of lifestyle questionnaire related to cancer (8 subscales, 41 items) is a reliable and valid measure to evaluate lifestyle behaviors related to cancer in adults.

Effect of resistant starch types as a prebiotic.

Since the role of intestinal microbiota in metabolism was understood, the importance of dietary components such as fibres and prebiotics, which affect the modulation of microbiota, has been increasing day by day. While all prebiotic components are considered dietary fibre, not every dietary fibre is considered a prebiotic. While fructooligosaccharides, galactooligosaccharides, inulin, and galactans are considered prebiotics, other fermentable carbohydrates are considered candidate prebiotic components based on in vitro and preclinical studies. Resistant starch, one of such carbohydrates, is considered a potential prebiotic component when it is made resistant to digestion naturally or chemically. In this review, both in vitro and in vivo studies in which the prebiotic capacity of type II, type III, and type IV resistant starch isolated from food and produced commercially was assessed were analyzed. According to the results of current studies, certain types of resistant starch are thought to have a high prebiotic capacity, and they may be candidate prebiotic components although positive results have not been achieved in all studies. KEY POINTS: • Resistant starch is undigested in the small intestine and is fermented in the large intestine. • Resistant starch fermentation positively affects the growth of Bifidobacterium and Lactobacillus. • Resistant starch can be considered a prebiotic ingredient.

Diagnosis and Management of Classical Hodgkin Lymphoma During the COVID-19 Pandemic.

The coronavirus disease 2019 (COVID-19) pandemic has brought life to a standstill globally. Intermittent quarantines were applied to control the pandemic and reduce contamination. During the pandemic, patients with hematological malignancies were among the most vulnerable population. Our aim was to compare in terms of demographic data, disease-related factors, symptom-to-diagnosis interval, diagnosis-to-treatment interval , and interim and end-of-treatment response in classical Hodgkin lymphoma patients diagnosed during the pandemic and in the pre-pandemic periods. A total of 90 patients were included, of which 65 and 25 were diagnosed in the 2 years before the pandemic and the 12-month period during the pandemic, respectively. Demographic features were comparable in both groups. Although the percentage of patients with advanced-stage disease was higher during the pandemic (64% vs 53.8%), this difference did not reach statistical significance (P = 0.384). The median symptom-to-diagnosis interval was significantly longer during the pandemic than was observed within the pre-pandemic era (16 weeks vs 8 weeks, P = 0.042). The median diagnosis-to-treatment intervals was similar in both groups (13 days vs 15 days, P = 0.253). In the pre-pandemic and pandemic periods, 85.2% and 72.7% of the patients had complete response at end-of-treatment evaluation, respectively (P = 0.208). We found that symptom-to-diagnosis interval was significantly prolonged during the pandemic. Higher percentage of patients with advanced-stage disease during the pandemic might also be due to this delay, nevertheless, this difference did not reach to a significant difference regarding treatment response in both groups.

Evaluation of trace elements in essential thrombocytosis and reactive thrombocytosis.

BACKGROUND: Trace elements (TE) are vital for cellular mechanisms at biological, chemical and molecular levels. The effects of TE in diagnosis, progression and treatment of essential thrombocytosis (ET), which is one of the chronic myeloproliferative neoplasms is a rare clonal stem cell disease characterized by increased thrombocyte numbers with impaired function, have not been elucidated in detail yet. The aim of the present study was to investigate the effects of TE alterations in an ET model and the efficacy of TE in ET treatment protocol by means of a vast number of TE. METHODS: Study groups were categorized as patients with ET diagnosis (ET group, n:30), patients with reactive thrombocytosis secondary to iron deficiency anemia (IDA-RT) (IDA-RT group, n:30) and healthy controls (HC group, n:30). Serum levels of copper (Cu), iron (Fe), cobalt (Co), chromium (Cr), aluminum (Al), silicon (Si), nickel (Ni), zinc (Zn), selenium (Se), manganese (Mn), boron (B) and magnesium (Mg) were analyzed utilizing inductively coupled plasma-optical emission spectrophotometer instrument (ICP-OES). Statistical analysis was evaluated using SPSS 23.0. RESULTS: ET group had statistically higher serum levels of Co and Mg (p < 0.05), Ni and Mn (p < 0.001), and lower Si (p < 0.05) than IDA-RT group. ET group had statistically higher serum levels of Co and Mn (p < 0.05), and Ni (p < 0.001), and lower Al, Si and Se (p < 0.001) than HC group. Serum levels of Fe, Al and Se (p < 0.001), and Mg (p < 0.01), and Zn (p < 0.05) in IDA-RT group were significantly lower than HC group. CONCLUSION: This novel study pointed out that alterations of many serum TE by means of both increment or decrement might have close relationship with mechanisms and complications of ET onset and follow-up. We consider that further research of TE would elucidate ethiopathogenesis and prognosis of ET. Thus, analysis of serum trace elements in essential thrombocytosis patients may be an important protocol by means of diagnosis, treatment and follow-up intervals.

Model-based machine learning for the recovery of lateral dose profiles of small photon fields in magnetic field.

Objective. To investigate the feasibility to train artificial neural networks (NN) to recover lateral dose profiles from detector measurements in a magnetic field.Approach. A novel framework based on a mathematical convolution model has been proposed to generate measurement-less training dataset. 2D dose deposition kernels and detector lateral fluence response functions of two air-filled ionization chambers and two diode-type detectors have been simulated without magnetic field and for magnetic fieldB = 0.35 and 1.5 T. Using these convolution kernels, training dataset consisting pairs of dose profilesDx,yand signal profilesMx,ywere computed for a total of 108 2D photon fluence profilesψ(x,y)(80% training/20% validation). The NN were tested using three independent datasets, where the second test dataset has been obtained from simulations using realistic phase space files of clinical linear accelerator and the third test dataset was measured at a conventional linac equipped with electromagnets. Mainresults. The convolution kernels show magnetic field dependence due to the influence of the Lorentz force on the electron transport in the water phantom and detectors. The NN show good performance during training and validation with mean square error reaching a value of 1e-6 or smaller. The corresponding correlation coefficientsRreached the value of 1 for all models indicating an excellent agreement between expectedDx,yand predictedDpredx,y.The comparisons betweenDx,yandDpredx,yusing the three test datasets resulted in gamma indices (1 mm/1% global) <1 for all evaluated data points.Significance. Two verification approaches have been proposed to warrant the mathematical consistencies of the NN outputs. Besides offering a correction strategy not existed so far for relative dosimetry in a magnetic field, this work could help to raise awareness and to improve understanding on the distortion of detector's signal profiles by a magnetic field.

The magnetic field dependent displacement effect and its correction in reference and relative dosimetry.

Objective.This study investigates the perturbation correction factors of air-filled ionization chambers regarding their depth and magnetic field dependence. Focus has been placed on the displacement or gradient correction factorPgr.Additionally, the shift of the effective point of measurementPeffthat can be applied to account for the gradient effect has been compared between the cases with and without magnetic field.Approach.The perturbation correction factors have been simulated by stepwise modifications of the models of three ionization chambers (Farmer 30013, Semiflex 3D 31021 and PinPoint 3D 31022, all from PTW Freiburg). A 10 cm × 10 cm 6 MV photon beam perpendicular to the chamber's axis was used. A 1.5 T magnetic field was aligned parallel to the chamber's axis. The correction factors were determined between 0.4 and 20 cm depth. The shift ofPefffrom the chamber's reference pointPref,Δz,was determined by minimizing the variation of the ratio between dose-to-waterDwzref+Δzand the dose-to-airD¯airzrefalong the depth.Main Results.The perturbation correction factors with and without magnetic field are depth dependent in the build-up region but can be considered as constant beyond the depth of dose maximum. Additionally, the correction factors are modified by the magnetic field.Pgrat the reference depth is found to be larger in 1.5 T magnetic field than in the magnetic field free case, where an increase of up to 1% is observed for the largest chamber (Farmer 30013). The magnitude ofΔzfor all chambers decreases by 40% in a 1.5 T magnetic field with the sign ofΔzremains negative.Significance.In reference dosimetry, the change ofPgrin a magnetic field can be corrected by applying the magnetic field correction factorkQmsrBwhen the chamber is positioned with itsPrefat the depth of measurement. However, due to the depth dependence of the perturbation factors, it is more convenient to apply theΔz-shift during chamber positioning in relative dosimetry.

Intraperitoneal vancomycin-induced immune thrombocytopenia.

Vancomycin is one of the drugs used in the peritonitis treatment regimen of peritoneal dialysis patients. Intraperitoneal route is generally preferred to provide rapid elimination of infective agents. Systemic toxicities of certain drugs after intraperitoneal administration are not very clear. The same also applies to vancomycin, although it has a considerable amount of systemic absorption after intraperitoneal administration. We herein report a case of severe thrombocytopenia, which was seen during the treatment of a peritonitis attack in a peritoneal dialysis patient. Culture studies revealed methicillin resistant staphylococci as the causative agent and the patient received intraperitoneal vancomycin per sensitivity analysis. Thrombocyte levels dropped abruptly to 3,900/µl after 10 days of vancomycin treatment. Clinical criteria pointed out to vancomycin-related immune thrombocytopenia. Platelet levels did not recover with initial dexamethasone treatment and platelet transfusions. In the meantime, the clinical course was also complicated with intracranial bleeding. Intravenous immunoglobulin treatment was applied and dexamethasone was switched to high-dose methylprednisolone. This latter treatment generated a response and platelet levels gradually increased to normal levels. The patient could be discharged without any sequelae. There have been two previous intraperitoneal vancomycin-related immune thrombocytopenia cases in the literature. Previous cases were reviewed, and the present case was given in comparison with the previous cases.

The dose response of PTW microDiamond and microSilicon in transverse magnetic field under small field conditions.

The aim of the present work is to investigate the behavior of two diode-type detectors (PTW microDiamond 60019 and PTW microSilicon 60023) in transverse magnetic field under small field conditions. A formalism based on TRS 483 has been proposed serving as the framework for the application of these high-resolution detectors under these conditions. Measurements were performed at the National Metrology Institute of Germany (PTB, Braunschweig) using a research clinical linear accelerator facility. Quadratic fields corresponding to equivalent square field sizesSbetween 0.63 and 4.27 cm at the depth of measurement were used. The magnetic field strength was varied up to 1.4 T. Experimental results have been complemented with Monte Carlo simulations up to 1.5 T. Detailed simulations were performed to quantify the small field perturbation effects and the influence of detector components on the dose response. The does response of both detectors decreases by up to 10% at 1.5 T in the largest field size investigated. InS = 0.63 cm, this reduction at 1.5 T is only about half of that observed in field sizesS > 2 cm for both detectors. The results of the Monte Carlo simulations show agreement better than 1% for all investigated conditions. Due to normalization at the machine specific reference field, the resulting small field output correction factors for both detectors in magnetic fieldkQclin,QmsrBare smaller than those in the magnetic field-free case, where correction up to 6.2% at 1.5 T is required for the microSilicon in the smallest field size investigated. The volume-averaging effect of both detectors was shown to be nearly independent of the magnetic field. The influence of the enhanced-density components within the detectors has been identified as the major contributors to their behaviors in magnetic field. Nevertheless, the effect becomes weaker with decreasing field size that may be partially attributed to the deficiency of low energy secondary electrons originated from distant locations in small fields.

The role of the construction and sensitive volume of compact ionization chambers on the magnetic field-dependent dose response.

PURPOSE: The magnetic-field correction factors k B , Q of compact air-filled ionization chambers have been investigated experimentally and using Monte Carlo simulations up to 1.5 T. The role of the nonsensitive region within the air cavity and influence of the chamber construction on its dose response have been elucidated. MATERIALS AND METHODS: The PTW Semiflex 3D 31021, PinPoint 3D 31022, and Sun Nuclear Cooperation SNC125c chambers were studied. The k B , Q factors were measured at the experimental facility of the German National Metrology Institute (PTB) up to 1.4 T using a 6 MV photon beam. The chambers were positioned with the chamber axis perpendicular to the beam axis (radial); and parallel to the beam axis (axial). In both cases, the magnetic field was directed perpendicular to both the beam axis and chamber axis. Additionally, the sensitive volumes of these chambers have been experimentally determined using a focused proton microbeam and finite element method. Beside the simulations of k B , Q factors, detailed Monte Carlo technique has been applied to analyse the secondary electron fluence within the air cavity, that is, the number of secondary electrons and the average path length as a function of the magnetic field strength. RESULTS: A nonsensitive volume within the air cavity adjacent to the chamber stem for the PTW chambers has been identified from the microbeam measurements and FEM calculations. The dose response of the three investigated ionization chambers does not deviate by more than 4% from the field-free case within the range of magnetic fields studied in this work for both the radial and axial orientations. The simulated k B , Q for the fully guarded PTW chambers deviate by up to 6% if their sensitive volumes are not correctly considered during the simulations. After the implementation of the sensitive volume derived from the microbeam measurements, an agreement of better than 1% between the experimental and Monte Carlo k B , Q factors for all three chambers can be achieved. Detailed analysis reveals that the stem of the PTW chambers could give rise to a shielding effect reducing the number of secondary electrons entering the air cavity in the presence of magnetic field. However, the magnetic field dependence of their path length within the air cavity is shown to be weaker than for the SNC125c chamber, where the length of the air cavity is larger than its diameter. For this chamber it is shown that the number of electrons and their path lengths in the cavity depend stronger on the magnetic field. DISCUSSION AND CONCLUSION: For clinical measurements up to 1.5 T, the required k B , Q corrections of the three chambers could be kept within 3% in both the investigated chamber orientations. The results reiterate the importance of considering the sensitive volume of fully guarded chambers, even for the investigated compact chambers, in the Monte Carlo simulations of chamber response in magnetic field. The resulting magnetic field-dependent dose response has been demonstrated to depend on the chamber construction, such as the ratio between length and the diameter of the air cavity as well as the design of the chamber stem.

The dose response of high-resolution diode-type detectors and the role of their structural components in strong magnetic field.

PURPOSE: This study aims to investigate the dose response of diode-type detectors in the presence of strong magnetic field and to understand the underlying mechanisms leading to the observed magnetic field dependence by close examinations on the role of the detector's design. MATERIALS AND METHODS: Three clinical diode-type detectors (PTW microSilicon type 60023, PTW microDiamond type 60019, and IBA Razor diode) have been studied. Measurements were performed at the linear accelerator experimental facility of the German National Metrology Institute (PTB, Braunschweig) with electromagnets up to 1.4 T to obtain the magnetic field correction factors k B , Q . The experimental results were compared to Monte Carlo simulations. Stepwise modifications of the detectors' models were performed to characterize the contributions of the structural components toward the magnetic field-dependent dose response. Additionally, systematic Monte Carlo study was conducted to elucidate the influence of the structural layers with varying density located above and beneath the detector's sensitive volume. RESULTS: The dose response of all investigated detectors decreases with magnetic field. As a result, the associated k B , Q factors increase by approximately 10% for the PTW detectors, and by 5% for the IBA Razor diode at 1.5 T. The sensitive volume itself was shown to cause negligible effect but the diode substrate with enhanced density situated directly below the sensitive volume contributes strongest to the observed magnetic field dependence. Systematic simulations revealed that k B , Q increases with magnetic field if the density of the structural layer located beneath the sensitive volume is higher than that of normal water (>1 g/cm3 ). In the case where the layer consists of low-density water (1.2 mg/cm3 ), k B , Q decreases with the magnetic field strength. On the contrary , if the structural layer with varying density is situated above the sensitive volume, the reversed effect could be observed. DISCUSSION AND CONCLUSION: The experimental and Monte Carlo results demonstrated that the dose response of the investigated diode-type detectors decreases in magnetic field. This observation can be generally attributed to the common construction of diode-type detectors, where structural components with enhanced density, for example the diode substrate, are situated below the sensitive volume. The results provide deeper insights into the behavior of clinical diode detectors when used in strong magnetic field.

Increased hip circumference in individuals with metabolic syndrome affects serum nesfatin-1 levels.

BACKGROUND: This case-control study was conducted to investigate the relationship between serum nesfatin-1 levels and nutritional status and blood parameters in patients diagnosed with metabolic syndrome. METHODS: Thirty patients (case) diagnosed with metabolic syndrome according to National Cholesterol Education Program-Adult Treatment Panel III criteria were included. Thirty healthy subjects (control) matched with patients with metabolic syndrome in terms of age, gender and body mass index were included. Three-day food consumption records were obtained. Anthropometric indices were measured and body composition was determined by bioelectrical impedance method. Biochemical parameters and serum nesfatin-1 levels were measured after 8 hours of fasting. RESULTS: Serum nesfatin-1 levels were 0.245±0.272 ng/mL in the case group and 0.528±0.987 ng/mL in the control group (p>0.05). There was a positive significant correlation between serum nesfatin-1 levels and body weight, waist and hip circumferences in the case group (p<0.05). Each unit increase in hip circumference measurement affects the levels of nesfatin by 0.014 times. In the control group, there was a positive significant correlation between body weight and serum nesfatin-1 levels (p<0.05). A significant correlation was detected between HbA1c and serum nesfatin-1 levels in the case group (p<0.05). A significant relationship was detected between dietary fibre intake and the serum nesfatin-1 levels in the case group (p<0.05). CONCLUSIONS: Anthropometric indices and blood parameters were correlated with serum nesfatin-1 levels in patients with metabolic syndrome. More clinical trials may be performed to establish the relationship between serum nesfatin-1 levels and nutritional status.

Regulatory Peptide Nesfatin-1 and its Relationship with Metabolic Syndrome.

Metabolic syndrome is associated with a group of conditions abdominal obesity, high triglyceride levels, reduction in low-density lipoprotein, increased blood pressure, and increased fasting blood glucose. Hence, it poses a risk for type 2 diabetes and cardiovascular diseases. The prevalence of metabolic syndrome increases with age. Nesfatin-1, which affects different systems, has recently been discovered as a regulatory peptide molecule. With the discovery of nesfatin-1, it has been reported to inhibit the intake of nutrients and have significant regulatory effects on energy metabolism. As nesfatin-1 is present in both central and peripheral tissues, it is thought to have many functions. In addition to its suppressive effect on food intake, nesfatin-1 has also been reported to have an effect on the blood glucose level for regulating cardiac functions and affecting obesity by providing weight loss. Considering the effects of nesfatin-1, it may be associated with metabolic syndrome.

The role of radiation-induced charge imbalance on the dose-response of a commercial synthetic diamond detector in small field dosimetry.

PURPOSE: Discrepancy between experimental and Monte Carlo simulated dose-response of the microDiamond (mD) detector (type 60019, PTW Freiburg, Germany) at small field sizes has been reported. In this work, the radiation-induced charge imbalance in the structural components of the detector has been investigated as the possible cause of this discrepancy. MATERIALS AND METHODS: Output ratio (OR) measurements have been performed using standard and modified versions of the mD detector at nominal field sizes from 6 mm × 6 mm to 40 mm × 40 mm. In the first modified mD detector (mD_reversed), the type of charge carriers collected is reversed by connecting the opposite contact to the electrometer. In the second modified mD detector (mD_shortened), the detector's contacts have been shortened. The third modified mD detector (mD_noChip) is the same as the standard version but the diamond chip with the sensitive volume has been removed. Output correction factors were calculated from the measured OR and simulated using the EGSnrc package. An adapted Monte Carlo user-code has been used to study the underlying mechanisms of the field size-dependent charge imbalance and to identify the detector's structural components contributing to this effect. RESULTS: At the smallest field size investigated, the OR measured using the standard mD detector is >3% higher than the OR obtained using the modified mD detector with reversed contact (mD_reversed). Combining the results obtained with the different versions of the detector, the OR have been corrected for the effect of radiation imbalance. The OR obtained using the modified mD detector with shortened contacts (mD_shortened) agree with the corrected OR, all showing an over-response of less than 2% at the field sizes investigated. The discrepancy between the experimental and simulated output correction factors has been eliminated after accounting for the effect of charge imbalance. DISCUSSIONS AND CONCLUSIONS: The role of radiation-induced charge imbalance on the dose-response of mD detector in small field dosimetry has been studied and quantified. It has been demonstrated that the effect is significant at small field sizes. Multiple methods were used to quantify the effect of charge imbalance with good agreement between Monte Carlo simulations and experimental results obtained with modified detectors. When this correction is applied to the Monte Carlo data, the discrepancy from experimental data is eliminated. Based on the detailed component analysis using an adapted Monte Carlo user-code, it has been demonstrated that the effect of charge imbalance can be minimized by modifying the design of the detector's contacts.

The polarity effect of compact ionization chambers used for small field dosimetry.

PURPOSE: The recent developments of compact air-filled ionization chambers for use in small photon beams have raised the needs to address the associated polarity effect. The polarity effect of five compact ionization chambers has been quantified at small field sizes. The origins of the polarity effect are studied experimentally and through Monte-Carlo simulations. For this purpose, the one-dimensional lateral dose-response functions were determined using positive and negative chamber's polarity. Monte-Carlo simulations were performed to study the underlying mechanism of the polarity effect by quantifying the charge imbalance in the collecting electrode and cable. METHODS: Five novel compact ionization chamber designs have been studied (PTW-Freiburg: Semiflex 3D 31021, PinPoint 3D 31022 and PinPoint 31023; IBA Dosimetry: Razor chamber CC01-G and Razor Nano-chamber CC003). Output ratios were measured down to a nominal field side length of 3 mm using both polarities to evaluate the polarity effect at different field sizes. The small field output correction factors were derived using a scintillator detector as reference. To identify the origins of the polarity effect, slit beam measurements were performed to obtain their lateral dose-response functions. All measurements were performed using three chamber orientations: axial, radial crossplane, and radial inplane. The chambers were modeled according to the manufacturers' blueprints using the Monte-Carlo package EGSnrc. The charge imbalance due to electrons entering and leaving the inner electrode and cable was studied using an adapted user-code. RESULTS: The output ratios obtained using all five chambers show field size-dependent polarity effects at small field sizes in the axial orientation, whereas no significant field size dependence of the polarity effect has been observed in the radial orientations. The chambers' lateral dose-response functions reveal that the radiation-induced charge imbalance in the inner electrode and cable is the main cause of the observed polarity effect at small field sizes. The effect is weakest for the largest PTW 31021 chamber but intensifies for smaller chambers with decreasing sensitive air volume. Consistent results have been obtained between Monte-Carlo simulations and measurement data. CONCLUSIONS: Awareness needs to be raised so that the polarity effect of novel compact ionization chambers is appropriately accounted for in small field dosimetry. The results in this work are useful to identify the magnitude of the polarity effect correction and to assist in the decisions on choosing the appropriate chambers and setups during measurements. The origins of the observed polarity effect have been elucidated using the chambers' lateral dose-response functions. The adapted Monte-Carlo user-code has been used to compute the radiation-induced charge imbalance in the chamber's components. It opens the possibility to study the chamber's design with the aim to minimize its polarity effect. Small field output correction factors computed according to TRS 483 have been reported for these investigated chambers.