221 research outputs found

    Highly porous photoluminescent diazaborole-linked polymers: synthesis, characterization, and application to selective gas adsorption

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    The formation of boronā€“nitrogen (Bā€“N) bonds has been widely explored for the synthesis of small molecules, oligomers, or linear polymers; however, its use in constructing porous organic frameworks remains very scarce. In this study, three highly porous diazaborole-linked polymers (DBLPs) have been synthesized by condensation reactions using 2,3,6,7,14,15-hexaaminotriptycene and aryl boronic acids. DBLPs are microporous and exhibit high Brunauerā€“Emmettā€“Teller surface area (730ā€“986 m2 gāˆ’1) which enable their use in small gas storage and separation. At ambient pressure, the amorphous polymers show high CO2 (DBLP-4: 4.5 mmol gāˆ’1 at 273 K) and H2 (DBLP-3: 2.13 wt% at 77 K) uptake while their physicochemical nature leads to high CO2/N2 (35ā€“42) and moderate CO2/CH4 (4.9ā€“6.2) selectivity. The electronic impact of integrating diazaborole moieties into the backbone of these polymers was investigated for DBLP-4 which exhibits green emission with a broad peak ranging from 350 to 680 nm upon excitation with 340 nm in DMF without photobleaching. This study demonstrates the effectiveness of Bā€“N formation in targeting highly porous frameworks with promising optical properties

    Effects of intrathecal bupivacaine and bupivacaine plus sufentanil in elderly patients undergoing transurethral resection

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    Introduction: The present study compared the effect of bupivacaine and bupivacaine + sufentanil on hemodynamic parameters and characteristics of spinal anesthesia in elderly patients undergoing transurethral resection of the prostate (TURP) under spinal anesthesia.Technical Considerations: The study included 40 American Society of Anesthesiologists (ASA) Iā€‘III patients scheduled to undergo TURP. Patients were blindly and randomly divided into two groups. Group B (n = 20) received 10 mg of intrathecal bupivacaine and group BS (n = 20) received 7.5 mg of bupivacaine + 5 Ī¼g of sufentanil. Sensory and motor block characteristics, hemodynamic changes, side effects, and time to first analgesic requirement were recorded. No differences in mean arterial pressure or heart rate, time for sensory blockade to reach the T10 level, and maximum sensory level were observed between the two groups. The time to first analgesic request was longer in group BS (P < 0.05). Motor block was significantly higher in group B (P < 0.05). In terms of side effects, no statistically significant differences occurred between the groups.Conclusions: Similar hemodynamic stability and sufficient level of sensory blockade were provided by bupivacaine and bupivacaine + sufentanil used for spinal anesthesia in patients undergoing TUR. Due to the fact that less motor block was observed and the time to first analgesic request was longer, the combination of bupivacaine + sufentanil might be appropriate for patients undergoing TUR.Key words: Bupivacaine, intrathecal, opioid, spinal, sufentani

    The effect of anesthesia type on stress hormone response: Comparison of general versus epidural anesthesia

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    Aim: The aim of this study was to investigate the effect of different types of anesthesia on stress hormones.Materials and Methods: The study was included 60 ASAI-II cases scheduled for major lower extremity surgery. The cases were randomized into 2Ā  groups: The EA group was administered epidural anesthesia and the GA group was administered standard general anesthesia. In order to evaluate the surgical trauma - related stress response, CRP, TSH, cortisol, and fasting blood sugar(FBS) levels were measured preoperatively, 30 min after surgical incision, and 24 h post surgery.Results: Between-group comparisons; Preoperative values were notĀ  significantly different between the groups.(P > 0,05) Pulse rate and cortisol values significantly higher in general group at 30 min. (P < 0,05), and the FBS values were significantly higher in the epidural group at 24 h.(P < 0,05) There were not found differences for other parameters at evaluation times.Conclusion: No differences were observed between the two anesthesia methods, in terms of minimizing the stress response due to surgical trauma during major low extremity surgery.Key words: Epidural anesthesia, general anesthesia, stress hormone

    Investigation of temporal bone asymmetry in cases with unilateral tinnitus: morphometric and multicentric clinical study

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    The aim of this multicentric study was to compare the anatomical structures of temporal bone in patients with unilateral tinnitus with their healthy ears. We also aimed at evaluating whether age and gender-related asymmetrical changes occur in temporal bones or not. Fifty two ears of 26 patients who had unilateral tinnitus were included into the retrospective study. The patients who had subjective nonpulsatile tinnitus and who previously had temporal computed tomography according to their file records were accepted to study. Temporal CT scans and audiometric results of patients were examined retrospectively. Middle ear volume, diameter of internal acoustic meats and diameter of jugular bulb were evaluated by both anatomist and radiologist, interobserverly. Internal acoustic meats and jugular bulb were found larger in the ears that had tinnitus than healthy ears; however, there was no statistically significance. The stereological morphometrical study of temporal bone asymmetry in humans correlate with sex is of importance for both otolarygologs and anatomists. These results will contribute to data on middle ear volume, internal acustic meats and jugular bulb sizes

    Structural and Magnetic Properties of Laā‚€.ā‚‡Srā‚€.ā‚ƒMnā‚ā‚‹ā‚“Niā‚“Oā‚ƒ (x ā‰¤ 0.4)

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    We have studied the structural and magnetic properties of La0.7Sr0.3Mn1-xNixO3 (x = 0.05, 0.1, 0.20, 0.30, and 0.40) perovskites using x-ray and neutron diffraction and magnetic measurements. Our data consist of neutron (Ī³ = 1.479ƅ) and x-ray (Ī³ = 1.5481ƅ; Cu KĪ±) powder diffraction and magnetization measurements. We previously suggested these systems transition from ferromagnetic to antiferromagnetic ordering with the intermediate concentrations containing coexisting domains of ferromagnetically and antiferromagnetically ordered states. Upon further detailed examination, we find that the samples are homogeneous and that neutron data can be fitted to a single long-range magnetically ordered state. The compositional dependent changes are driven by a shift in the dominant near neighbor interaction from ferromagnetic to antiferromagnetic. In the intermediate compositions, peaks previously identified as due to antiferromagnetic ordering, in fact arise from charge ordering; the system remains in a ferromagnetic state where the Ni moments are antiparallel to the Mn moments. This interpretation supersedes multiphase and spin glass models for these complex systems

    The effect of thrombolytic therapy on QT dispersion in acute myocardial infarction and its role in the prediction of reperfusion arrhythmias

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    Purpose: We aimed to determine the effect of intravenous thrombolytic therapy on QT dispersion (QTd) and its role in the prediction of reperfusion arrhythmias.Materials and Methods: Twenty patients with acute myocardial infarction (MI) were enrolled in the study. Measurements of QTd were carried outĀ  prior to thrombolytic therapy and before discharge. The patients were examined for ventricular arrhythmias with 24ā€‘h Holter electrocardiography monitoring after treatment and the relationship between ventricular arrhythmias and the QTd values in the early phase of MI was investigated.Results: The values of QTd were significantly higher during the early phase of MI (60 Ā± 5.32 ms) than those in the late phase (53.35 Ā± 4.07 ms) (P = 0.032). There was no correlation between isolated, bigeminal, trigeminal and total ventricular premature beats, accelerated idioventricular rhythm (AIVR) with QTd values. However, the patients with sustained ventricular tachycardia (VT), prolonged VT and sustained AIVR had higher corrected QTd (92 ms1/2, 97.8 ms1/2, 81.7 ms1/2, respectively) than the patients without these arrhythmias (74 ms1/2, 56.3 ms1/2, 58.28 ms1/2,Ā  respectively) (P = 0.022, 0.013, 0.018).Conclusion: The values of QTd may be significantly reduced in the 1st week of acute MI and measurement of QTd in the early phase of MI may have a correlation with the following reperfusion arrhythmias: Sustained VT, prolonged VT and AIVR.Key words: Arrhythmia, myocardial infarction, QT dispersion, reperfusion, thrombolytic therap

    Hospital managers' need for information in decision-making--An interview study in nine European countries.

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    Assessments of new health technologies in Europe are often made at the hospital level. However, the guidelines for health technology assessment (HTA), e.g. the EUnetHTA Core Model, are produced by national HTA organizations and focus on decision-making at the national level. This paper describes the results of an interview study with European hospital managers about their need for information when deciding about investments in new treatments. The study is part of the AdHopHTA project. Face-to-face, structured interviews were conducted with 53 hospital managers from nine European countries. The hospital managers identified the clinical, economic, safety and organizational aspects of new treatments as being the most relevant for decision-making. With regard to economic aspects, the hospital managers typically had a narrower focus on budget impact and reimbursement. In addition to the information included in traditional HTAs, hospital managers sometimes needed information on the political and strategic aspects of new treatments, in particular the relationship between the treatment and the strategic goals of the hospital. If further studies are able to verify our results, guidelines for hospital-based HTA should be altered to reflect the information needs of hospital managers when deciding about investments in new treatments

    Decision-making regulatory framework of the introduction of health technologies at the hospitals in Ukraine

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    The limited resources of the health care system and the COVID-19 pandemic encourage more rational and cost-effective administrative and clinical decisions. To achieve the best health care within available resources, the introduction of the most efficient technologies should be supported, considering organizational, social and ethical issues. Assessment of health technologies at different levels, namely national/regional and hospital, is becoming increasingly important. Adherence to cost-effective approaches to administrative and clinical decision-making will ensure the rational use of the state budget and improve clinical outcomes, improve the quality and life expectancy of patients. The purpose of the study was to analyze the current regulatory framework for the introduction of health technologies (medicines and medical devices) at the hospital level. During the research the methods of content analysis, historical, system-analytical, generalization was used. According to the analysis of the decision-making regulatory framework for the health technologyā€™s introduction, it was drawn the next conclusions. The active HTA development in Ukraine is noted. In a short time, a legal framework for state HTA for medicines was created and approved, amendments were made to the Law of Ukraine ā€˜On Public Procurementā€™ and other Ukraineā€™s laws on medicine procurement under managed entry agreements, the further steps for development of the HTA ecosystem in Ukraine were identified. The legal framework for the circulation of medical devices needs to be updated in Ukraine, starting with technical regulations in accordance with EU regulations ā„–745 and ā„–746 and further approval of the Law on Medical Devices. Procedures for evaluation and selection of medicines and medical devices at the level of medical institutions are absent in Ukraine and require separate elaboration. The introduction of HB-HTA will help hospital managers to make independent, transparent, reasonable, and impartial management decisions on the selection of drugs and medical devices. The obtained results prove the need for further research of everyday decision-making practices on the introduction of health technologies at the hospitals, development of methodology for hospital-based HTA and update regulation of HB-HTA in the current legal framework of Ukraine
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