26 research outputs found

    Application of X-ray powder diffraction and differential scanning calorimetry for identification of counterfeit drugs

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    X-ray analysis confirmed that in all investigated samples, the active API (acetylsalicylic acid and ascorbic acid) was present. The values of the interplanar distance dhkl for the studied samples are in good accordance with those presented in the ICDD database. The intensities of the diffraction lines depend on the content of the component in the tested preparation. Therefore, different intensities of lines for the APIs were observed in the obtained diffraction patterns. Thermal analysis of the studied substances showed that during the thermal analysis, the following phenomena might occur: dehydration and (or) melting, crystalline transformation. Moreover, it was found that the chemical structure of the studied compounds affects the process of their thermal decomposition. The data obtained during these investigations can be useful in quick tests of physicochemical discrepancies and abnormalities between potential components of pharmaceutical preparations. The evidence for the interaction can be obtained by comparing DSC and TG curves of the drug and the excipient, as well as those of their physical mixtures. For this reason, the study of characteristics of thermal decomposition of drugs and excipients is necessary. Based on the above investigations, it may be stated that a combination of two methods: XRPD and DSC can be used to distinguish the original drugs from counterfeit products, e.g., by checking for the presence of the correct API or by a comparison of the drugs fingerprint

    X-ray and thermal analysis of selected drugs containing acetaminophen

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    Studies carried out by X-ray and thermal analysis confirmed that acetaminophen (paracetamol), declared by the manufacturers as an Active Pharmaceutical Ingredient (API), was present in all studied medicinal drugs. Positions of diffraction lines (2θ angles) of the studied drugs were consistent with standards for acetaminophen, available in the ICDD PDF database Release 2008.ID2θI values were lower than 0.2°, confirming the authenticity of the studied drugs. Also, the values of interplanar distances dhkl for the examined samples were consistent with those present in the ICDD. Presence of acetaminophen crystalising in the monoclinic system (form I) was confirmed. Various line intensities for API were observed in the obtained diffraction patterns, indicating presence of the preferred orientation of the crystallites in the examined samples. Thermal analysis of the studied substances confirmed the results obtained by X-ray analysis. Drugs containing only acetaminophen as an API have melting point close to that of pure acetaminophen. It was found that presence of other active and auxiliary substances affected the shapes and positions of endothermal peaks significantly. A broadening of endothermal peaks and their shift towards lower temperatures were observed accompanying an increase in the contents of additional substances being “impurities” in relation to the API. The results obtained by a combination of the two methods, X-ray powder diffraction (XRPD) and differential scanning calorimetry/thermogravimetry (DSC/TGA), may be useful in determination of abnormalities which can occur in pharmaceutical preparations, e.g., for distinguishing original drugs and forged products, detection of the presence of a proper polymorphic form or too low content of the active substance in the investigated drug

    Luminescence of SiO2-BaF2:Tb3+, Eu3+ nano-glass-ceramics made from sol-gel method at low temperature

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    The synthesis and characterization of multicolor light-emitting nanomaterials based on rare earths (RE3+) are of great importance due to their possible use in optoelectronic devices, such as LEDs or displays. In the present work, oxyfluoride glass-ceramics containing BaF2 nanocrystals co-doped with Tb3+, Eu3+ ions were fabricated from amorphous xerogels at 350 C. The analysis of the thermal behavior of fabricated xerogels was performed using TG/DSC measurements (thermogravimetry (TG), differential scanning calorimetry (DSC)). The crystallization of BaF2 phase at the nanoscale was confirmed by X-ray diffraction (XRD) measurements and transmission electron microscopy (TEM), and the changes in silicate sol–gel host were determined by attenuated total reflectance infrared (ATR-IR) spectroscopy. The luminescent characterization of prepared sol–gel materials was carried out by excitation and emission spectra along with decay analysis from the 5D4 level of Tb3+. As a result, the visible light according to the electronic transitions of Tb3+ (5D4 ! 7FJ (J = 6–3)) and Eu3+ (5D0 ! 7FJ (J = 0–4)) was recorded. It was also observed that co-doping with Eu3+ caused the shortening in decay times of the 5D4 state from 1.11 ms to 0.88 ms (for xerogels) and from 6.56 ms to 4.06 ms (for glass-ceramics). Thus, based on lifetime values, the Tb3+/Eu3+ energy transfer (ET) efficiencies were estimated to be almost 21% for xerogels and 38% for nano-glass-ceramics. Therefore, such materials could be successfully predisposed for laser technologies, spectral converters, and three-dimensional displays

    The usefulness of X-ray diffraction and thermal analysis to study dietary supplements containing iron

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    X-ray powder diffraction (XRPD) and thermal analysis (differential scanning calorimetry/ derivative of thermogravimetry (DSC/DTG)) are solid-state techniques that can be successfully used to identify and quantify various chemical compounds in polycrystalline mixtures, such as dietary supplements or drugs. In this work, 31 dietary supplements available on the Polish market that contain iron compounds, namely iron gluconate, fumarate, bisglycinate, citrate and pyrophosphate, were evaluated. The aim of the work was to identify iron compounds declared by the manufacturer as food supplements and to try to verify compliance with the manufacturer’s claims. Studies performed by X-ray and thermal analysis confirmed that crystalline iron compounds (iron (II) gluconate, iron (II) fumarate), declared by the manufacturers, were present in the investigated dietary supplements. Iron (II) bisglycinate proved to be semi-crystalline. However, depending on the composition of the formulation, it was possible to identify this compound in the tested supplements. For amorphous iron compounds (iron (III) citrate and iron (III) pyrophosphate), the diffraction pattern does not have characteristic diffraction lines. Food supplements containing crystalline iron compounds have a melting point close to the melting point of pure iron compounds. The presence of excipients was found to affect the shapes and positions of the endothermic peaks significantly. Widening of endothermic peaks and changes in their position were observed, as well as exothermic peaks indicating crystallization of amorphous compounds. Weight loss was determined for all dietary supplements tested. Analysis of the DTG curves showed that the thermal decomposition of most food supplements takes place in several steps. The results obtained by a combination of both simple, relatively fast and reliable XRPD and DSC/DTG methods are helpful in determining phase composition, pharmaceutical abnormalities or by detecting the presence of the correct polymorphic form

    Novel multicomponent titanate-germanate glasses : synthesis, structure, properties, transition metal, and rare earth doping

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    Novel multicomponent titanate-germanate glasses singly doped with transition metal (Cr3+) and rare earth ions (Eu3+) were synthesized and the glass transition temperatures and thermal stability parameters were determined using DSC measurements. X-ray di raction analysis confirmed fully amorphous nature of the received samples. Their structural and optical properties were compared with germanate glasses without TiO2. Correlation between local structure and optical properties in titanate-germanate glasses is well evidenced by FT-IR, Raman, EPR, and luminescence spectroscopy. In particular, luminescence spectra and their decays are examined for glass samples, where GeO2 was partially substituted by TiO2

    Study of the structure, magnetic, thermal and electrical characterisation of ZnCr2Se4: Ta single crystals obtained by chemical vapour transport

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    The new series of single-crystalline chromium selenides, Ta-doped ZnCr2Se4, was synthesised by a chemical vapour transport method to determine the impact of a dopant on the structural and thermodynamic properties of the parent compound. We present comprehensive investigations of structural, electrical transport, magnetic, and specific heat properties. It was expected that a partial replacement of Cr ions by a more significant Ta one would lead to a change in direct magnetic interactions between Cr magnetic moments and result in a change in the magnetic ground state and electric transport properties of the ZnCr2xTaxSe4 (x = 0.05, 0.06, 0.07, 0.08, 0.1, 0.12) system. We found that all the elements of the cubic system had a cubic spinel structure; however, the doping gain linearly increased the ZnCr2xTaxSe4 unit cell volume. Doping with tantalum did not significantly change the semiconductor and magnetic properties of ZnCr2Se4. For all studied samples (0 x 0.12), an antiferromagnetic order (AFM) below TN~22 K was observed. However, a small amount of Ta significantly reduced the second critical field (Hc2) from 65 kOe for x = 0.0 (ZnCr2Se4 matrix) up to 42.2 kOe for x = 0.12, above which the spin helical system changed to ferromagnetic (FM). The Hc2 reduction can lead to strong competition among AFM and FM interactions and spin frustration, as the specific heat under magnetic fields H < Hc2 shows a strong field decrease in TN

    Role of catheter-directed therapies in the treatment of acute pulmonary embolism. Expert opinion of the Polish PERT Initiative, Working Group on Pulmonary Circulation, Association of Cardiovascular Interventions, and Association of Intensive Cardiac Care

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    Thanks to advances in interventional cardiology technologies the catheter-directed treatment has become recently a viable therapeutic option in the treatment of patients with acute pulmonary embolism at high risk of early mortality. Current transcatheter techniques allow local fibrinolysis or embolectomy with minimal risk of complications. Therefore they can be considered in high risk patients as an alternative to surgical pulmonary embolectomy when systemic thrombolysis is contraindicated or ineffective. They are also considered in patients with intermediate — high risk with a lack of improvement or clinical deterioration despite anticoagulation. The purpose of this article is to present the role of transcatheter techniques in the treatment of patients with acute pulmonary embolism. We describe current knowledge and experts’ opinion in this field. Interventional treatment is described in the broader context of patient care organization and therapeutic modalities. We present the organization and responsibilities of pulmonary embolism response teams, the role of pre-procedural imaging, peri-procedural anticoagulation, patients selection, timing of intervention and intensive care support. Currently available catheter directed therapies are discussed in detail including standardized protocols, definitions of procedure success and failure. This expert opinion has been developed in collaboration with experts from various Polish scientific societies signifying the role of teamwork in the care for patients with acute pulmonary embolism

    Rola terapii przezcewnikowych w leczeniu ostrej zatorowości płucnej — opinia Polskiej Inicjatywy PERT, Sekcji Krążenia Płucnego, Asocjacji Interwencji Sercowo-Naczyniowych i Asocjacji Intensywnej Terapii Kardiologicznej Polskiego Towarzystwa Kardiologicznego

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    Dzięki postępom w zakresie technologii kardiologii interwencyjnej leczenie przezcewnikowe stało się w ostatnich latach realną opcją terapeutyczną w leczeniu pacjentów z ostrą zatorowością płucną z wysokim ryzykiem wczesnej śmiertelności. Obecnie stosowane techniki przezcewnikowe umożliwiają miejscową fibrynolizę lub embolektomię przy minimalnym ryzyku powikłań. Stąd mogą być rozważane u pacjentów z grupy wysokiego ryzyka jako alternatywa dla chirurgicznej embolektomii płucnej, gdy systemowa tromboliza jest przeciwwskazana lub nieskuteczna. Rozważane są również u pacjentów z grupy średniego–wysokiego ryzyka, u których pomimo leczenia przeciwzakrzepowego nie uzyskano poprawy lub nastąpiło pogorszenie stanu klinicznego. Celem artykułu było przedstawienie roli technik przezcewnikowych w leczeniu chorych z ostrą zatorowością płucną zgodnie z aktualną wiedzą i opinią ekspertów. Leczenie interwencyjne opisano w szerszym kontekście organizacji opieki nad pacjentem. Przedstawiono organizację i zadania zespołu szybkiego reagowania w zatorowości płucnej, rolę obrazowania przedzabiegowego, zasady antykoagulacji okołozabiegowej, kryteria kwalifikacji pacjentów, wyboru odpowiedniego czasu interwencji oraz rolę intensywnej terapii. Szczegółowo omówiono dostępne terapie przezcewnikowe, w tym wystandaryzowane protokoły, definicje sukcesu i niepowodzenia procedury. Niniejszy dokument został opracowany we współpracy z ekspertami z różnych polskich towarzystw naukowych, co podkreśla rolę pracy zespołowej w opiece nad chorym z ostrą zatorowością płucną

    Long-term outcomes and quality of life following implementation of dedicated mitral valve Heart Team decisions for patients with severe mitral valve regurgitation in tertiary cardiovascular care center

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    Background: This study was purposed to investigate which treatment strategy was associated with the most favourable prognosis for patients with severe mitral regurgitation (MR) following Heart Team (HT)-decisions implementation. Methods: In this retrospective study, long-term outcomes of patients with severe MR qualified after HT discussion to: optimal medical treatment (OMT) alone, OMT and MitraClip (MC) procedure or OMT and mitral valve replacement (MVR) were evaluated. The primary endpoint was defined as cardiovascular (CV) death and the secondary endpoints included all-cause mortality, myocardial infarctions (MI), strokes, hospitalizations for heart failure exacerbation and CV events during a mean (standard deviation [SD]) follow-up of 29 (15) months. Results: From 2016 to 2019, 176 HT meetings were held and a total of 157 participants (mean age [SD] = 71.0 [9.2], 63.7% male) with severe MR and completely implemented HT decisions (OMT, MC or MVR for 53, 58 and 46 patients, respectively) were included into final analysis. Comparing OMT, MC and MVR groups statistically significant differences between the implemented procedures and occurrence of primary and secondary endpoints with the most frequent in OMT-group were observed (p &lt; 0.05). However, for interventional strategy MC was non-inferior to MVR for all endpoints (p &gt; 0.05). General health status assessed at the end of follow-up were significantly the lowest for MVR, then for MC and the highest for OMT-group (p &lt; 0.01). Conclusions: In the present study it was demonstrated that after careful HT evaluation of patients with severe MR at high risk of surgery, percutaneous strategy (MC) can be considered as equivalent to surgical treatment (MVR) with non-inferior outcomes

    We Do Not Like It: A Likert-Type Scale Survey on the Attitudes of a Young Population towards the Transhumanistic Theory of Education

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    Transhumanists assume that future education may be purely based on technological stimulation. The question is: Do potential clients of education “like” such vision? In order to check this, we asked over one thousand two hundred young Poles to evaluate their identification with the transhumanistic theory of education. The results are quite surprising: its show that they disagree with the assumptions of this theory, while they rather agree with the postulates of more traditional (and no technology-based) concepts of education
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