Continuous wavelet transform methods for the simultaneous determinations and dissolution profiles of valsartan and hydrochlorothiazide in tablets

ABSTRACT Continuous wavelet transform (CWT) was proposed for the simultaneous determination and dissolution profiles of valsartan (VAL) and hydrochlorothiazide (HCT) in tablets, without the use of a chemical separation procedure. The CWT approach was applied to the original UV spectra and their ratio spectra in the optimal wavelength ranges. After testing several wavelet families, Mexican hat function-CWT and Daubechies7-CWT (mexh-CWT and db7-CWT, respectively) were found to be suitable for the transformation of the original UV spectra. In the following procedure, mexh-CWT and Coiflets3-CWT (coif3-CWT) were found to be appropriate for the signal analysis of ratio spectra (RS) of VAL/HCT and HCT/VAL. Calibration graphs for VAL and HCT were obtained by measuring db7-CWT and mexh-CWT amplitudes in the transformation of the original absorption spectra and RS-coif-CWT and RS-mexh-CWT amplitudes in the transformation of the ratio spectra. The validity and applicability of the proposed CWT methods were evaluated through the analysis of an independent set of synthetic binary mixtures consisting of VAL and HCT. The proposed signal processing methods were then successfully applied to the simultaneous quantitative evaluation and simultaneous dissolution profiles of the related drugs in commercial tablets, with good agreement reported for the experimental results

Istodobno spektrofotometrijsko određivanje losartan kalija, amlodipin besilata i hidroklorotiazida u farmaceutskim pripravcima kemometrijskom metodom

In the present work, four different spectrophotometric methods for simultaneous estimation of losartan potassium, amlodipine besilate and hydrochlorothiazide in raw materials and in formulations are described. Overlapped data was quantitatively resolved by using chemometric methods, classical least squares (CLS), multiple linear regression (MLR), principal component regression (PCR) and partial least squares (PLS). Calibrations were constructed using the absorption data matrix corresponding to the concentration data matrix, with measurements in the range of 230.5350.4 nm (∆λ = 0.1 nm) in their zero order spectra. The linearity range was found to be 840, 15 and 315 μg ml1 for losartan potassium, amlodipine besilate and hydrochlorothiazide, respectively. The validity of the proposed methods was successfully assessed for analyses of drugs in the various prepared physical mixtures and in tablet formulations.U radu su opisane četiri spektrofotometrijske metode za istodobno određivanje losartan kalija, amlodipin besilata i hidroklorotiazida u sirovinama i farmaceutskim pripravcima. Podaci koji su se preklapali kvantitativno su razlučeni kemometrijskim metodama, klasičnom metodom najmanjih kvadrata (CLS), multiplom linearnom regresijom (MLR), regresijom glavnih komponenata (PCR) te metodom parcijalnih najmanjih kvadrata (PLS). Kalibracije su provedene koristeći podatke o ovisnosti apsorpcije o koncentracijama, mjereći spektre nultog reda u rasponu 230,5350,4 nm (∆λ = 0,1 nm). Linearnost za losartan kalij bila je 840, za amlodipin besilat 15, a za hidroklorotiazid 315 μg ml1. Valjanost predloženih metoda uspješno je potvrđena analizom navedenih lijekova u različitim pripremljenim smjesama i tabletama

Decreasing trends in cardiovascular mortality in Turkey between 1988 and 2008.

BACKGROUND: Cardiovascular disease (CVD) mortality increased in developed countries until the 1970s then started to decline. Turkey is about to complete its demographic transition, which may also influence mortality trends. This study evaluated trends in coronary heart disease (CHD) and stroke mortality between 1988 and 2008. METHODS: The number of deaths by cause (ICD-8), age and sex were obtained from the Turkish Statistical Institute (TurkStat) annually between 1988 and 2008. Population statistics were based on census data (1990 and 2000) and Turkstat projections. European population standardised mortality rates for CHD and stroke were calculated for men and women over 35 years old. Joinpoint Regression was used to identify the points at which a statistically significant (p < 0.05) change of the trend occurred. RESULTS: The CHD mortality rate increased by 2.9% in men and 2.0% in women annually from 1988 to 1994, then started to decline. The annual rate of decline for men was 1.7% between 1994-2008, whilst in women it was 2.8% between 1994-2000 and 6.7% between 2005-2008 (p < 0.05 for all periods).Stroke mortality declined between 1990-1994 (annual fall of 3.8% in both sexes), followed by a slight increase between 1994-2004 (0.6% in men, 1.1% in women), then a further decline until 2008 (annual reduction of 4.4% in men, 7.9% in women) (p < 0.05 for all periods). CONCLUSIONS: A decrease in CVD mortality was observed from 1995 onwards in Turkey. The causes need to be explored in detail to inform future policy priorities in noncommunicable disease control

Political connections and corporate financial decision making

This paper investigates whether and how political connections influence managerial financial decisions. Our study reveals that those firms that have a politician on its board of directors are highly leveraged, use more long-term debt, hold large excess cash and are associated with low quality financial reporting compared to their non-connected counterparts. These effects escalate with the strength of the connected politician and whether he or his party is in power. The winning party effect is observed to be stronger than victory by the politician himself. Overall, our paper provides strong evidence that political connection is a two-edged sword. It is indeed a valuable resource for connected firms, but it comes at a cost of higher agency problems

Capital Structure and Oligarch Ownership

This study examines the effects of oligarch ownership on corporate capital structures. Using panel data from Ukraine, I find that oligarch-owned companies employ significantly more debt and liabilities than their peers. However, there is no direct relation between oligarch ownership and target capital structure. Whereas the determinants of target leverage are similar across all owners, differences in firm characteristics also have a fairly small effect. I show that larger leverage is due to better access to debt, which results in lower rebalancing costs and faster restructurings of oligarch-owned companies. The findings clearly suggest that oligarchs benefit from the accumulated advantages

Medication calculation skills of graduating nursing students within European context.

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadAim: The aim of this study is to evaluate the medication calculation skills of graduating nursing students in six European countries and analyse the associated factors. Background: Medication calculation skills are fundamental to medication safety, which is a substantial part of patient safety. Previous studies have raised concerns about the medication calculation skills of nurses and nursing students. Design: As part of a broader research project, this study applies a multinational cross-sectional survey design with three populations: graduating nursing students, nurse managers and patients. Methods: The students performed two calculations (tablet and fluid) testing medication calculation skills requiring different levels of conceptual understanding and arithmetic. The managers and patients answered one question about the students' medication kills. In total, 1,796 students, 538 managers and 1,327 patients participated the study. The data were analysed statistically. The STROBE guideline for cross-sectional studies was applied. Results: Almost all (99%) of the students performed the tablet calculation correctly, and the majority (71%) answered the fluid calculation correctly. Older age, a previous degree in health care and satisfaction with their current degree programme was positively associated with correct fluid calculations. The patients evaluated the students' medication skills higher than the nurse managers did and the evaluations were not systematically aligned with the calculation skills tested. Conclusions: Nursing students have the skills to perform simple medication calculations, but a significant number of students have difficulties with calculations involving multiple operations and a higher level of conceptual understanding. Due to the variation in students' medication calculation skills and the unalignment between the managers' and patients' evaluations and the calculation tests, further research is needed. Relevance to clinical practice: Graduating nursing students enter clinical field as qualified professionals, but there is still room for improvement in their medication calculation skills. This calls for attention in the fields of clinical nursing, education and research. Keywords: drug dosage calculations; graduating nursing students; medication calculation skills; nurse managers; patients.Academy of Finland European Commissio

Bacterial cellulose as a new graft model for the Turkish delight technique in rhinoplasty: An experiment in 20 rats

We conducted an experiment to investigate the effectiveness of bacterial cellulose, a new graft material, in correcting and preventing dorsal nasal disorder in rhinoplasty. The experiment was performed on 20 Wistar albino rats. The rats were evenly divided into two groups: a fascia group and a cellulose group. In the fascia group, grafts from the conchal cartilage were removed, shredded, and then wrapped in temporal muscle fascia. In the cellulose group, shredded cartilage was wrapped in the bacterial cellulose. These shredded gristle grafts, which were also placed in a subcutaneous area at the back of the rats, were excised after 60 days. We then performed histopathology to compare the health and integrity of the cartilage and the degree of vascularization, fibrosis, and chronic inflammation in the two groups. We found a significantly greater degree of vascularization (p = 0.004) and fibrosis (p = 0.005) in the fascia group and a significantly greater degree of chronic inflammation (p = 0.023) in the cellulose group. We found no statistically significant difference between the two groups in terms of cartilage health and integrity. Our results suggest that bacterial cellulose grafting may play a role as an alternative to fascia grafting for the wrapping of shredded cartilages in Turkish delight grafting, but further investigation is needed. © 2016 Vendome Group, LLC

High temperature-tolerant tomato lines: bioactive compounds.

The functional quality of newly developed high temperature tolerant tomato lines was investigated in terms of lycopene, ß-carotene, ascorbic acid and phenolic compounds to assist breeders for the selection of high temperature tolerant tomato varieties with high nutritional quality. 19 tomato lines including control varieties from the “Turkey F1 Hybrid vegetable variety and quality line development” project were selected for investigation. Line 11 was superior in lycopene and ß-carotene content while line 18 in ascorbic acid as compared to control varieties Cansun F1 and Alsancak RN F1. Urfa 2012 and line 28 were found to have the highest numbers of phenolic compounds. Chlorogenic acid, rutin and trans-ferulic acid were the main phenolic compounds detected in all tomato lines at high concentrations. These newly released tomato lines can be used as value-added germplasm or parents to develop new heat tolerant cultivars in a breeding programmes or as a commercial cultivar for their superior functional qualities.TUBİTA