235 research outputs found

    On the Norms of Circulant and rr-Circulant Matrices With the Hyperharmonic Fibonacci Numbers

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    In this paper, we study norms of circulant and rr-circulant matrices involving harmonic Fibonacci and hyperharmonic Fibonacci numbers. We obtain inequalities by using matrix norms

    On the Harmonic and Hyperharmonic Fibonacci Numbers

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    In this paper, we study the theory of the harmonic and the hyperharmonic Fibonacci numbers. Also, we get some combinatoric identities like as harmonic and hyperharmonic numbers and we obtain some useful formulas for Fn\mathbb{F}_{n}, which is finite sums of reciprocals of Fibonacci numbers. We obtain spectral and Euclidean norms of circulant matrices involving harmonic and hyperharmonic Fibonacci numbers

    GCD matrices, posets, and nonintersecting paths

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    We show that with any finite partially ordered set one can associate a matrix whose determinant factors nicely. As corollaries, we obtain a number of results in the literature about GCD matrices and their relatives. Our main theorem is proved combinatorially using nonintersecting paths in a directed graph.Comment: 10 pages, see related papers at http://www.math.msu.edu/~saga

    Protective effect of leukotriene receptor antagonist montelukast on smoking-induced lung injury in Wistar rats.

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    Increased activation of alveolar macrophage, neutrophil and mast cell has been proven in cigarette smoking (CS)-related lung disorders (CSLD). An increased production of cysteinyl-leukotrienes (LTs), which are mediators secreted from the mentioned cells, in response to CS has been shown in humans. The protective effect of LT1 receptor-1 antagonist (LTR-1AT) on CSLD is, however, not known. In this study we aimed to determine whether there is any protective effect of a LTR-1AT, montelukast (MK), on CSLD in Wistar rats. Nine controls and twenty-three smoke-exposed rats were enrolled into this study. Controls were exposed to non-filtered air, and the smoke-exposed rats were exposed to CS for 6 h/day, 6 days/week for three weeks. The CS-exposed rats were also treated with 0.1 mg/kg/day of MK or saline. Morphometric criteria for lung injury were determined as the mean linear intercept of alveolar septa (Lm), the volume density of alveolar septa (Vvspt) and the density of the alveolar surface area per unit volume of lung parenchyma (Sva.pa). Lung mast cells (LMC), which are a major source of LTs, were also counted. Results showed that Lm of the control group was significantly lower and Vvspt, Sva.pa of the controls were significantly higher compared to those of the CS-exposed groups. Animals treated with MK had significant protection against CSLD. Lm was significantly higher and Vvspt, Sva.pa were lower in the saline group than in the MK-treated group. The number of LMC in the CS-exposed groups was also significantly higher than that in the control group. Based on these results, one can suggest that some part of the pathogenesis of CSLD may be related to an enhanced LTs synthesis and LTR-1AT. Therefore, montelukast may protect against active or passive smoking-induced lung injury and related disorders.</p

    Adult Attention Deficit Hyperactivity Disorder: Neurobiology, Diagnostic Problems and Clinical Features

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    Attention-deficit/hyperactivity disorder (ADHD) is a chronic, lifelong neurobeha-vioral disorder with childhood-onset, which seriously impairs the affected adults in a variety of daily living functions like academic, social and occupational functioning. Prevalence of ADHD declines with age in the general population. The approximate prevalence rates of ADHD is 8% in childhood, 6% in adolescence and 4% in adulthood. The unclear validity of DSM-IV diagnostic criteria for this condition can lead to reduced prevalence rates by underestimation of the prevalence of adult ADHD. The disorder is characterized by behavioral symptoms of inattention, hyperactivity, and impulsivity across the life cycle and is associated with considerable morbidity and disability. Although its etiology remains unclear, considerable evidence documents its strong neurobiological and genetic underpinnings. ADHD is associated with a high percentage of comorbid psychiatric disorders in every lifespan. In adulthood between 65-89% of all patients with ADHD suffer from one or more additional psychiatric disorders, above all mood and anxiety disorders, substance use disorders and personality disorders, which complicate the clinical picture in terms of diagnostics, treatment and outcome issues. The high comorbidity with other psychiatric disorders, the resulting deficits in social competences and risky health behavior that often go along with a diminished life quality must be stressed in these patients. Preventive and therapeutic interventions should be taken at an early stage to counteract the possible negative influences of ADHD on functioning and relationships. In this paper, we reviewed the historical aspects, epidemiology, neurobiology, comorbidity, diagnostic difficulties and clinical features of adult ADHD

    In Vitro Cytotoxicity of GuttaFlow Bioseal, GuttaFlow 2, AH-Plus and MTA Fillapex

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    Introduction: The aim of the present in vitro study was to evaluate the cytotoxicity of different sealers including GuttaFlow Bioseal, GuttaFlow 2, AH-Plus and MTA Fillapex on L929 murine fibroblasts. Methods and Materials: Samples of GuttaFlow Bioseal, GuttaFlow 2, AH-Plus and MTA Fillapex were fabricated in Teflon disks of 5 mm diameter and 3 mm thickness. L929 fibroblasts were exposed to the extracts of these materials for 3, 24, 72 and 168 h at 37°C with 5% CO2. Cell viability was evaluated by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was evaluated by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. The data were analysed by ANOVA. Results: GuttaFlow Bioseal was nontoxic at all experimental time points (P&gt;0.05), whereas MTA Fillapex and AH-Plus were toxic (P&lt;0.001). At 7 days, there were more viable cells in the GuttaFlow 2 group than in the control group, and MTA Fillapex was more cytotoxic than AH-Plus. There were more apoptotic cells in the MTA Fillapex and AH-Plus groups than in the other groups at 3 h (P&lt;0.001). Conclusion: GuttaFlow sealers are less cytotoxic than MTA Fillapex and AH-Plus. At all experimental time points, there was no significant difference in the cell viability between the GuttaFlow Bioseal group and the control group.Keywords: AH-Plus; Cytotoxicity; GuttaFlow Bioseal; GuttaFlow 2; MTA Fillapex; MTT Assay; TUNEL Assa

    Investigation of Stem Cell Applications on In Vitro Fertilization in Rats

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    ΔΕΝ ΔΙΑΤΙΘΕΤΑΙ ΠΕΡΙΛΗΨΗWe aimed to search the effects of bone marrow-derived mesenchymal stem cell-conditioned media on in vitro fertilization by investigation of lifetime of germ cells cleavage, degeneration rates and embryo quality. For this purpose, firstly MSCs were isolated from femurs and tibias of the rat, and cells were cultured until the fourth passage. Sperm and oocytes were collected from male and female rats. Oocytes were added in Human Tubal Fluid Media (HTFM), Single Step Media (SSM), Alpha-MEM Media (AMM) and Bone Marrow-Derived Mesenchymal Stem Cell-Conditioned Media (CM). Thousand sperm were added into the media which including oocytes. Embryos were allowed to produce by IVF. The development of the embryos was followed until the 11th day, and the arrest, degeneration rates and alive embryos were established. The embryos reached 2, 4, 8, 16 cells stages and morula stage in the CM. While AMM had a negative effect on fertilization and embryo development, the most favourable effect was shown to be caused by CM in comparison with the other medias. These results have shown that the beneficial effects of CM in IVF would be a significant increase in the rate of fertility and development of embryos

    The Effects of the Melatonin Treatment on the Oxidative Stress and Apoptosis in Diabetic Eye and Brain

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    Oxidative stress plays an important role in the development of complications in diabetes mellitus. Antioxidant therapy has been thought to decrease oxidative stress. The objective of the present study was to explore the effects of melatonin (MLT) on oxidative stress in diabetic rat eye and brain tissue by using immunohistochemical methods. Diabetes was induced by streptozotocin, (STZ, 55 mg/kg/i.p) in adult rats. MLT was given 10 mg/kg/i.p once a day for 2 weeks beginning from the sixth week. Six weeks later, rats were divided into three groups: control (CR), STZ-induced diabetic (STZ), and STZ-induced diabetic group received melatonin (STZ+MLT). Although no significant difference was observed with respect to antioxidant status, NOS activity tended to be higher in the untreated diabetic rats than in the treated rats. It was observed that MLT treatment improved the histopathological changes including apoptosis and oxidative stress in brain and eye in diabetic rat

    Delirium Associated with Olanzapine Therapy in an Elderly Male with Bipolar Affective Disorder

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    Atypical antipsychotic medications are commonly used to treat symptoms of delirium. Olanzapine has been successfully used in the treatment of delirium. However, there have been few case reports of delirium associated with olanzapine. We hereby report a case of delirium associated with olanzapine therapy. Possible risk factors and underlying pathogenesis is discussed
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