Drug resistance in pulmonary tuberculosis in new and previously treated cases: Experience from Turkey

SummaryThe emergence of drug resistance is a major problem for tuberculosis (TB) control. The aim of this study was to determine the rates of resistance against TB drugs in patients with pulmonary tuberculosis (PTB). Data from 387 patients with active PTB between the years of 1999 and 2004 from the Research and Education Hospital for Chest Diseases and Chest Surgery were evaluated retrospectively. The patients were categorized as new, re-treatment, extrapulmonary and chronic cases. The study group consisted of 268 (69%) new, 57 (14.7%) re-treatment, 49 (12.6%) extrapulmonary and 13 (3.3%) chronic TB cases. The rates of resistance to isoniazid (INH), rifampicin (R), ethambutol (E) and streptomycin (S) were calculated separately for each group. The resistance to any of the drugs was 7.8% in the new cases, 58.5% in the re-treatment cases and 100% in the chronic cases. The multidrug-resistance (MDR)-TB rates were found to be 2.16%, 11.3% and 92.3% among the new, re-treatment and chronic cases, respectively. These data are important as they reflect the drug resistance rates during the pre-notification time period in western Turkey

Understanding degradation mechanisms in cobalt-free lithium-ion battery cathodes from first-principles

The increasing demand for Li-ion batteries requires moving away from cobalt-containing cathode materials because Co is scarce, expensive, and geographically strongly localized. Co-free Ni-rich cathodes and their derivatives are, in principle, an excellent alternative, as Ni is more abundant, less expensive, and environmentally friendlier than Co. LiNiO₂, the parent of Ni-rich cathode materials, is structurally identical and chemically similar to LiCoO₂, offering almost the same theoretical capacity. However, LiNiO₂ and related materials often degrade rapidly during electrochemical cycling, with degradation modes including Li/Ni mixing, stacking faults, and surface reconstructions, making them unsuitable for battery applications. In this thesis, we used first-principles calculations to investigate the origin of Li/Ni mixing and stacking-fault formation, and we explored if entropy stabilization can be exploited to stabilize cobalt-free cathode materials. At half Li concentration, layered Li₀.₅NiO₂ is metastable, and the ground state is the spinel phase. The phase transformation from the layered to the spinel structure involves Ni migration and leads to Li/Ni mixing but only occurs at high temperatures. To better understand Li/Ni mixing in LiNiO₂, we determined the layered-to-spinel transformation in Li₀.₅NiO₂. We found the mechanism determined by electronic-structure symmetries, leading to a different route and intermediates from other well-studied lithium transition-metal oxides, such as Li₀.₅MnO₂. One important complication in LiNiO₂ is that it forms stoichiometry defects in which Ni atoms replace Li atoms, yielding off-stoichiometric Li₁₋zNi₁₊zO₂. Li/Ni mixing, a process in which Li and Ni interchange sites, can occur during synthesis or electrochemical cycling, and it reduces the capacity by impeding the intercalation of Li ions during battery operation. We unraveled the Li/Ni-mixing mechanism and explained the impact of off-stoichiometry on Li/Ni mixing from an electronic and geometric perspective. We also determined the role of the Li concentration and the Ni oxidation state on the driving force for Li/Ni cation mixing. At low Li contents, stacking faults can form in LiNiO₂, a process in which Ni layers glide relative to each other. These planar glides can alter the particle morphology, create new surfaces, and accelerate degradation. Stacking faults form unfavorable sites for Li, which impedes intercalation and lowers the capacity. We investigated the role of off-stoichiometry in planar glides and Ni migration in the presence of stacking faults. We determined how the distribution of Ni across the Li layers affects planar glides and explained how Li/Ni mixing may prevent the formation of stacking faults. Finally, to provide alternatives to the Ni-rich family of Co-free cathodes, we investigated if entropic stabilization can be exploited to stabilize layered cathode materials and prevent their degradation. We computationally assessed equimolar layered high-entropy oxides, a new class of layered materials that exhibits substitutional disorder in the transition-metal layer. We found that the general strategy of entropic stabilization is viable and identified four candidate compositions with good predicted energy density as a starting point for further studies. The research conducted as part of this thesis advances the understanding of degradation in Co-free cathode materials and identifies a direction for developing stable Co-free layered cathode materials with high energy density

Comparison of national early warning score 2 and quick sepsis-related organ failure assessment score in predicting severe coronavirus disease 2019: A validation study

BACKGROUND AND AIM: Coronavirus disease 2019 (COVID-19) has imposed a heavy burden on the intensive care unit and health care systems worldwide. Therefore, early detection of high-risk patients in terms of poor prognosis is crucial. We aimed to compare the diagnostic yield of the two most reliable scoring systems (National Early Warning Score 2 [NEWS 2] and quick Sepsis-related Organ Failure Assessment [qSOFA]) when repeatedly performed during the COVID-19 course. METHODS: The data of 403 COVID-19 patients admitted to our hospital between March 1, 2020, and November 30, 2020, were retrospectively reviewed. The demographic, comorbidity, and clinical data of the patients were recorded in the evaluation. NEWS2 and qSOFA score were retrospectively calculated at the time of admission, 24th hour, and 48th hour. We compared the effectiveness of qSOFA and NEWS2 for predicting the prognosis of COVID-19. RESULTS: The mean NEWS2 at the time of admission, 24th hour, and 48th hour was significantly higher in patients with poor outcomes than in patients with good outcomes. The 48th-hour NEWS2 was found to be the most successful score in predicting the poor outcome (AUC: 0.854; 95% CI: 0.81-0.88; p<0.001). NEWS2 at 0th, 24th, and 48th hours were found to be superior to qSOFA scores at the same time points. CONCLUSIONS: NEWS2 was superior to qSOFA in determining the need for intensive care support and/or mortality. A high NEWS2 at the 48th hour seems to be more valuable to predict worse outcomes

The eighth staging system of non-small cell lung cancer and its practical implications

Staging is an essential part of the approach to patients with lung cancer. The primary goal of the tumor classification is to correctly describe the anatomic extent of the disease. The anatomic extent of the tumor has a major impact on the treatment selection and prognosis. The general approach to patients with non-small cell lung cancer include mediastinal staging and non-thoracic staging methods, history and physical examination, imaging, minimally invasive techniques, and invasive surgical techniques. The current lung cancer staging system is the eighth edition of the tumor, node, and metastasis (TNM) classification, which was took effect in January 2017. In this article, staging methods and the definitions for current T, N, M descriptors and the stage groups in non-small cell lung cancer are reviewed. New definitions of T, N, and M factors seem to better indicate the most optimal treatment option for an individual patient and to better predict the survival in patients

PNEUMOLOGISTS' APPROACH TOWARDS EUTHANASIA

Introduction: With the legalization of active euthanasia in the Netherlands and Belgium in recent years, euthanasia has become a subject of discussion again. It is important that physicians, particularly oncologists express their opinion about euthanasia. The aim of this study was to reveal what pneumologists who worked in oncology clinics thought about euthanasia