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Background: Red cell distribution width (RDW) has been shown to have predictive properties in different diseases as well as solid cancers. Aim: We aimed to investigate the discriminative properties of RDW in benign and malignant breast lesions. Subjects and Methods: In a retrospective cohort study the files of patients who underwent surgery for fibroadenomas (Group A) and breast cancer with axillary lymph node metastasis (Group B) were reviewed. The pathology reports and laboratory parameters and demographics of the patients were recorded for comparison. The patients were later excluded if they had an hemoglobin level below 12 mg/dl and the outliers were removed for a comparison. Seventy-six patients in the fibroadenoma group and 62 patients in the breast malignancy group were compared for the RDW levels to predict the presence of malignancy. Receiver operating characteristic curves were plotted for RDW and a threshold for prediction of malignancy was calculated. Results: The difference in RDW levels between group A and group B was found to be significant, 13,10% (IQR 12.60 -13.70) versus 13,80% (IQR 13.10-14.40) respectively, P = 0,00. The area under the curve was 0.71 (95% confidence interval 0.62 to 0.79), P = 0,00. For the threshold of 13,75 the positive predictive value was 67.35 (95% CI 55.72 to 77.17) and negative predictive value was 67.42 (95% CI 60.76% to 73.44). Conclusion: The RDW levels, after adjusted for anemia, were found to have a positive prediction for malignancy in more than two thirds of the patients for the level of 13.75%.
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Anemia , Neoplasias da Mama , Índices de Eritrócitos , Feminino , Humanos , Curva ROC , Estudos RetrospectivosRESUMO
BACKGROUND: Open appendectomy (OA) has been the gold standard for a long time. Laparoscopic appendectomy (LA) has gained wide acceptance and popularity, outdoing open approach. Yet, conversion may be required when laparoscopic approach fails. AIMS: To predict conversion from laparoscopic appendectomy to open appendectomy sing Oreo-ratio radiological appendices diameter. MATERIALS AND METHODS: This is a retrospective cohort study conducted on 320 (included) patients who underwent appendectomy between January 2018 and August 2018 in the General Surgery departmentof Haseki Training and Research Hospital, Istanbul, Turkey. Appendiceal diameter obtained during preoperative radiological screening was evaluated about its relationship to conversion from LA to OA. Age, sex, inflammatory serum parameters and pathology reports were also investigated. RESULTS: A total of 269 (84%) cases were started LA and 17 (6,3%) laparoscopic cases were converted to open. The appendix diameter, the grade of inflammation (perforated or gangrenous), age, and c-reactive protein (CRP) were found to have significant importance in conversion, P = 0.003, P = 0.000, P = 0.042, and P = 0.018, respectively. When a cutoff of 50 years was chosen for age, the odds ratio (OR) was 3. For the appendiceal diameter of 14 mm, the OR was 3.0286. CONCLUSION: Preoperative evaluation of appendix diameter is a quick and useful method for a surgeon to distinguish cases with risk of conversion in the emergency department. The other risk factors associated with conversion of LA to OA are grade of inflammation, age and CRP levels.
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Apendicectomia/métodos , Apendicite/cirurgia , Apêndice/diagnóstico por imagem , Laparoscopia/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Apendicectomia/efeitos adversos , Apendicite/diagnóstico por imagem , Apêndice/anatomia & histologia , Apêndice/patologia , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Feminino , Humanos , Inflamação/sangue , Laparoscopia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Estudos Retrospectivos , Resultado do Tratamento , Turquia/epidemiologiaRESUMO
INTRODUCTION: Red cell distribution width (RDW) is a parameter that reflects the heterogeneity in the size of the circulating erythrocytes. Elevated levels of RDW have been found related to various pathologic conditions including cancers. We hypothesized that elevated RDW levels might correspond to advanced stages of pancreatic cancer. METHODS: The medical files and pathology reports of patients who underwent Whipple procedure were evaluated in a retrospective casecontrol study. The relationship of RDW to age, gender, cancer antigen 19-9 (CA 19-9), blood hemoglobin levels, stage of the tumor, tumor size, tumor grade, number of lymph nodes with metastasis, the status of lymphovascular and perineural invasion were investigated. A oneto-two, age- and- gender matched group of seemingly healthy patients was used to compare the levels of RDW between the patients of pancreatic head malignancy and healthy people. ROC (receiver operating characteristics) curves analysis was conducted to define a threshold to discriminate malignant pancreatic head tumors from healthy control subjects. Then, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (+LR), and negative likelihood ratio (-LR) were calculated. RESULTS: The median age was 61 years (IRQ 54.75-69). The median RDWs were 15.20% (IQR 13.20-19.50) vs 13.00 (IQR 12.60-13.48) in the pancreas adenocancer and the control group, respectively, p=0.000). There was significant relationship between RDW and the grade of the tumor, p=0.026. An RDW level of 14% was obtained as a result of the ROC curves analysis and the positive predictivity about malignancy was 70.73% with a negative predictive rate of 89.95% compared with the healthy group of patients. CONCLUSION: The elevated levels of RDW in patients with a pancreatic mass may point to a possible malignancy; however, an elevated RDW in a patient with a malignant pancreatic head mass is related to the grade of the disease, not the stage.
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Fatores Etários , Índices de Eritrócitos , Eritrócitos/citologia , Neoplasias Pancreáticas/sangue , Fatores Sexuais , Idoso , Antígeno CA-19-9/sangue , Forma Celular , Tamanho Celular , Grupos Controle , Feminino , Hemoglobina A/análise , Humanos , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasias Pancreáticas/patologia , Curva ROC , Projetos de Pesquisa , Estudos Retrospectivos , Sensibilidade e Especificidade , Carga TumoralRESUMO
In this manuscript, we have carried out a combined study of density functional theory and Monte Carlo (MC) simulations for a thorough examination of a single-layer (SL) Ti2B structure. On the basis of first-principles, spin-polarized density functional calculations, we showed that a free standing SL-Ti2B structure is dynamically and thermally stable. The atomic structure, phonon spectrum, electronic and magnetic properties of the SL-Ti2B structure are analyzed. In order to determine ground state, the structure of Ti2B is optimized for four types of spin oriented configurations, namely ferromagnetic (FM), antiferromagnetic Néel, antiferromagnetic Zigzag and antiferromagnetic Stripy and non-magnetic states. We found that the spin configuration FM corresponds to the ground state for SL-Ti2B. We also found that the Raman-active modes are softening in the antiferromagnetic cases. On the basis of these results, MC simulations show that the magnetic susceptibility, thermal variations of magnetization, and specific heat curves of Ti2B exhibit a phase transition between paramagnetic and FM phases at the Curie temperature of 39.06 K. While SL-Ti2B possess a little out-of-plane magnetic anisotropy, it has not any in plane magnetic anisotropy energy.
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We have studied the structural stability of monolayer and bilayer arsenene (As) in the buckled (b) and washboard (w) phases with diffusion quantum Monte Carlo (DMC) and density functional theory (DFT) calculations. DMC yields cohesive energies of 2.826(2) eV/atom for monolayer b-As and 2.792(3) eV/atom for w-As. In the case of bilayer As, DMC and DFT predict that AA-stacking is the more stable form of b-As, while AB is the most stable form of w-As. The DMC layer-layer binding energies for b-As-AA and w-As-AB are 30(1) and 53(1) meV/atom, respectively. The interlayer separations were estimated with DMC at 3.521(1) Å for b-As-AA and 3.145(1) Å for w-As-AB. A comparison of DMC and DFT results shows that the van der Waals density functional method yields energetic properties of arsenene close to DMC, while the DFT + D3 method closely reproduced the geometric properties from DMC. The electronic properties of monolayer and bilayer arsenene were explored with various DFT methods. The bandgap values vary significantly with the DFT method, but the results are generally qualitatively consistent. We expect the present work to be useful for future experiments attempting to prepare multilayer arsenene and for further development of DFT methods for weakly bonded systems.
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Recent experiments revealed that monolayer α-RuCl3 can be obtained by a chemical exfoliation method and exfoliation or restacking of nanosheets can manipulate the magnetic properties of the materials. In this paper, the electronic and magnetic properties of an α-RuCl3 monolayer are investigated by combining first-principles calculations and Monte Carlo simulations. From first-principles calculations, we found that the spin configuration of FM corresponds to the ground state for α-RuCl3, however, the other excited zigzag oriented spin configuration has an energy of 5 meV per atom higher than the ground state. The energy band gap is found to be 3 meV using PBE functionals. When the spin-orbit coupling effect is taken into account, the corresponding energy gap is determined to be 57 meV. We also investigate the effect of the Hubbard U energy terms on the electronic band structure of the α-RuCl3 monolayer and revealed that the band gap increases approximately linearly with increasing U value. Moreover, spin-spin coupling terms (J1, J2, and J3) have been obtained using first-principles calculations. By benefiting from these terms, Monte Carlo simulations with a single site update Metropolis algorithm have been implemented to elucidate the magnetic properties of the considered system. Thermal variations of magnetization, susceptibility and also specific heat curves indicate that monolayer α-RuCl3 exhibits a phase transition between ordered and disordered phases at the Curie temperature of 14.21 K. We believe that this study can be utilized to improve two-dimensional magnetic materials.
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Diazinon is one of the most widely used organophosphate insecticides (OPIs) in agriculture and public health programs. Reactive oxygen species (ROS) caused by OPIs may be involved in the toxicity of various pesticides. The aim of this study was to investigate how diazinon affects lipid peroxidation (LPO) and the antioxidant defense system in vivo and the possible ameliorating role of vitamins E and C. For this purpose, experiments were done to study the effects of DI on LPO and the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) in adult rat heart. Experimental groups were: (1) control group, (2) diazinon treated (DI) group, (3) DI+vitamins E and C-treated (DI+Vit) group. The levels of malondialdehyde (MDA) and the activities of SOD and CAT increased significantly in the DI group compared with the control group. The activity of SOD and the levels of MDA decreased significantly in the DI+Vit group compared with the DI group. The differences between the DI+Vit and control groups according to the MDA levels and the activities of both SOD and CAT were statistically significant. These results suggest that treating rats with a single dose of diazinon increases LPO and some antioxidant enzyme activities in the rat myocardium and, in addition, that single-dose treatment with a combination of vitamins E and C after the administration of diazinon can reduce LPO caused by diazinon, though this treatment was not sufficiently effective to reduce the values to those in control group.