110 research outputs found
Fluctuation conductivity due to the preformed local pairs
We investigated the properties of a system where the itinerant electrons coexist and interact with the preformed local pairs. Using the nonperturbative continuous unitary transformation technique we show that Andreev-type scattering between these charge carriers gives rise to the enhanced diamagnetic response and is accompanied by appearance of the Drude peak inside the pseudogap regime ω ≤ 2Δpg . Both effects are caused by the short-range superconducting correlations above the transition temperature Tc. In fact, the residual diamagnetism has been detected by the torque magnetometry in the lanthanum and bismuth cuprate superconductors at temperatures up to ~1.5 T c. In this work we show how the superconducting correlations can be observed in the ac and dc conductivity.
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Effects of Low Carbohydrate High Protein (LCHP) diet on atherosclerotic plaque phenotype in mice : FT-IR and Raman imaging
Low Carbohydrate High Protein (LCHP) diet displays pro-atherogenic effects, however, the exact mechanisms involved are still unclear. Here, with the use of vibrational imaging, such as Fourier transform infrared (FT-IR) and Raman (RS) spectroscopies, we characterize biochemical content of plaques in Brachiocephalic Arteries (BCA) from ApoE/LDLR−/− mice fed LCHP diet as compared to control, recomended by American Institute of Nutrition, AIN diet. FT-IR images were taken from 6–10 sections of BCA from each mice and were complemented with RS measurements with higher spatial resolution of chosen areas of plaque sections. In aortic plaques from LCHP fed ApoE/LDLR−/− mice, the content of cholesterol and cholesterol esters was increased, while that of proteins was decreased as evidenced by global FT-IR analysis. High resolution imaging by RS identified necrotic core/foam cells, lipids (including cholesterol crystals), calcium mineralization and fibrous cap. The decreased relative thickness of the outer fibrous cap and the presence of buried caps were prominent features of the plaques in ApoE/LDLR−/− mice fed LCHP diet. In conclusion, FT-IR and Raman-based imaging provided a complementary insight into the biochemical composition of the plaque suggesting that LCHP diet increased plaque cholesterol and cholesterol esters contents of atherosclerotic plaque, supporting the cholesterol-driven pathogenesis of LCHP–induced atherogenesis
Vibrational and quantum-chemical study of pH dependent molecular structures of (hydroxypyridin-4-yl-methyl)phosphonic acid
Abstract Vibrational study of pH dependent molecular structures of (hydroxypyridin-4-yl-methyl)phosphonic acid is discussed based on experimental data and quantum-chemical calculations. A cationic, a zwitteranionic as well as mono-and dianionic forms of the acid are considered in our work. Equilibrium geometries, harmonic vibrational frequencies were calculated for all species of (hydroxypyridin-4-yl-methyl)phosphonic acid deprotonated in different way by using DFT (B3PW91) with 6-31G(d,p) basis set. The computed properties are compared to the experimental values. Additionally, charge distributions and aromaticity index were calculated for species studied here by using generalized atomic polar tensor (GAPT) and harmonic oscillator model of aromaticity (HOMA), respectively
Infekcyjne zapalenie wsierdzia zastawki aortalnej i płucnej u 20-letniego pacjenta z dwujamową prawą komorą i ubytkiem przegrody międzykomorowej
W niniejszej pracy przedstawiono przypadek 20-letniego pacjenta z dwujamową prawą komorą
i z ubytkiem przegrody międzykomorowej (VSD), powikłanym infekcyjnym zapaleniem
wsierdzia. U chorego zastosowano terapię przeciwbakteryjną i przeciwgrzybiczą, a następnie
zakwalifikowano go do leczenia operacyjnego. Korekcja obejmowała zamknięcie ubytku przegrody
międzykomorowej łatą goreteksową, resekcję drogi odpływu prawej komory oraz wszczepienie
homogaftu aortalnego i płucnego. W pracy przedstawiono problemy związane z diagnostyką,
farmakoterapią oraz leczeniem operacyjnym infekcyjnego zapalenia wsierdzia. (Folia
Cardiol. 2004; 11: 681-686
Infekcyjne zapalenie wsierdzia zastawki aortalnej i płucnej u 20-letniego pacjenta z dwujamową prawą komorą i ubytkiem przegrody międzykomorowej
W niniejszej pracy przedstawiono przypadek 20-letniego pacjenta z dwujamową prawą komorą
i z ubytkiem przegrody międzykomorowej (VSD), powikłanym infekcyjnym zapaleniem
wsierdzia. U chorego zastosowano terapię przeciwbakteryjną i przeciwgrzybiczą, a następnie
zakwalifikowano go do leczenia operacyjnego. Korekcja obejmowała zamknięcie ubytku przegrody
międzykomorowej łatą goreteksową, resekcję drogi odpływu prawej komory oraz wszczepienie
homogaftu aortalnego i płucnego. W pracy przedstawiono problemy związane z diagnostyką,
farmakoterapią oraz leczeniem operacyjnym infekcyjnego zapalenia wsierdzia. (Folia
Cardiol. 2004; 11: 681-686
Raman-based spectrophenotyping of the most important cells of the immune system
INTRODUCTION: Human peripheral blood mononuclear cells (PBMCs) are a heterogeneous population of cells that includes T and B lymphocytes. The total number of lymphocytes and their percentage in the blood can be a marker for the diagnosis of several human diseases. Currently, cytometric methods are widely used to distinguish subtypes of leukocytes and quantify their number. These techniques use cell immunophenotyping, which is limited by the number of fluorochrome-labeled antibodies that can be applied simultaneously. OBJECTIVE: B and T lymphocytes were isolated from peripheral blood obtained from healthy human donors. METHODS: The immunomagnetic negative selection was used for the enrichment of B and T cells fractions, and their purity was assessed by flow cytometry. Isolated cells were fixed with 0.5% glutaraldehyde and measured using confocal Raman imaging. K-means cluster analysis, principal component analysis and partial least squares discriminant methods were applied for the identification of spectroscopic markers to distinguish B and T cells. HPLC was the reference method for identifying carotene in T cells. RESULTS: Reliable discrimination between T and B lymphocytes based on their spectral profile has been demonstrated using label-free Raman imaging and chemometric analysis. The presence of carotene in T lymphocytes (in addition to the previously reported in plasma) was confirmed and for the first time unequivocally identified as β-carotene. In addition, the molecular features of the lymphocytes nuclei were found to support the discriminant analysis. It has been shown that although the presence of carotenoids in T cells depends on individual donor variability, the reliable differentiation between lymphocytes is possible based on Raman spectra collected from individual cells. CONCLUSIONS: This proves the potential of Raman spectroscopy in clinical diagnostics to automatically differentiate between cells that are an important component of our immune system
Evidence-based medicine, a case report of adenocarcinoma of the lung
Powszechna dostępność charakteryzujących się wysoką jakością badań wielorzędowych aparatów do tomografii komputerowej przyniosła znaczący wzrost wykrywania pojedynczych guzków płuca. Zważywszy na wysoką zapadalność na raka płuca i stale niezadowalające wyniki leczenia, możliwość wykrywania zmian mało zaawansowanych, poddających się doszczętnej resekcji, budziły duże nadzieje. Wykorzystywana w badaniach przesiewowych niskodawkowa tomografia komputerowa klatki piersiowej wskazuje na obecność pojedynczych guzków płuca nawet u 50% palących papierosy osób powyżej 50 roku życia. Biorąc pod uwagę istotność problemu klinicznego, kluczowe jest ustalenie optymalnego sposobu diagnostyki pojedynczych guzków płuca. Pomocne w tym zakresie mogą być wytyczne American College of Chest Physcians. Wskazują one, iż w dokładnym oszacowaniu prawdopodobieństwa złośliwości zmiany należy oprzeć się na doświadczeniu klinicznym bądź też użyć jednego ze zweryfikowanych modeli typu Bayesian analysis. W poniższej pracy przedstawiamy przypadek chorego z pojedynczym guzkiem płuca, wskazując na rozbieżności decyzji diagnostycznych i terapeutycznych opartych na doświadczeniu diagnostów i klinicystów oraz wytycznych opartych na badaniach „kohortowych”.Common access to high resolution computed tomography has increased the early detection of solitary lung nodules. The incidence of lung cancer is high with poor outcomes in the advanced stages of the disease. The best prognosis is achieved with complete surgical resection of a solitary small lung nodule. Low-dose computed tomography used as the screening test reveals solitary nodule in up to 50% of cigarettes smokers above 50 years of age. The guidelines of American College of Chest Physicians can be a helpful method to assess the potential malignancy of a nodule. Clinical experience and Bayesian analysis should be considered in a case of a suspected lung nodule on CT scans.
We present the case of a patient with a solitary lung nodule, and emphasise discrepancies between diagnostic and clinical assessment based on the evidence-based medicine guidelines
Relationship between anti-DFS70 autoantibodies and oxidative stress
Background: The anti-DFS70 autoantibodies are one of the most commonly and widely described agent of unknown clinical significance, frequently detected in healthy individuals. It is not known whether the DFS70 autoantibodies are protective or pathogenic. One of the factors suspected of inducing the formation of anti-DFS70 antibodies is increased oxidative stress. We evaluated the coexistence of anti-DFS70 antibodies with selected markers of oxidative stress and investigated whether these antibodies could be considered as indirect markers of oxidative stress. Methods: The intensity of oxidative stress was measured in all samples via indices of free-radical damage to lipids and proteins such as total oxidant status (TOS), concentrations of lipid hydroperoxides (LPH), lipofuscin (LPS), and malondialdehyde (MDA). The parameters of the non-enzymatic antioxidant system, such as total antioxidant status (TAS) and uric acid concentration (UA), were also measured, as well as the activity of superoxide dismutase (SOD). Based on TOS and TAS values, the oxidative stress index (OSI) was calculated. All samples were also tested with indirect immunofluorescence assay (IFA) and 357 samples were selected for direct monospecific anti DFS70 enzyme-linked immunosorbent assay (ELISA) testing. Results: The anti-DFS70 antibodies were confirmed by ELISA test in 21.29% of samples. Compared with anti-DFS70 negative samples we observed 23% lower concentration of LPH (P =.038) and 11% lower concentration of UA (P =.005). TOS was 20% lower (P =.014). The activity of SOD was up to 5% higher (P =.037). The Pearson correlation showed weak negative correlation for LPH, UA, and TOS and a weak positive correlation for SOD activity. Conclusion: In samples positive for the anti-DFS70 antibody a decreased level of oxidative stress was observed, especially in the case of samples with a high antibody titer. Anti-DFS70 antibodies can be considered as an indirect marker of reduced oxidative stress or a marker indicating the recent intensification of antioxidant processes. © The Author(s) 2022. **Please note that there are multiple authors for this article therefore only the name of the first 30 including Federation University Australia affiliate “Fadi Charchar” is provided in this record*
P2 nucleotide receptors on C2C12 satellite cells
In developing muscle cells environmental stimuli transmitted by purines binding to the specific receptors are crucial proliferation regulators. C2C12 myoblasts express numerous purinergic receptors representing both main classes: P2X and P2Y. Among P2Y receptors we have found the expression of P2Y1, P2Y2, P2Y4, P2Y6 and P2Y12 family members while among P2X receptors P2X4, P2X5 and P2X7 were discovered. We have been able to show that activation of those receptors is responsible for ERK class kinase activity, responsible for regulation of cell proliferation pathway. We have also demonstrated that this activity is calcium dependent suggesting Ca2+ ions as secondary messenger between receptor and kinase regulatory system. More specifically, we do suspect that in C2C12 myoblasts calcium channels of P2X receptors, particularly P2X5 play the main role in proliferation regulation. In further development of myoblasts into myotubes, when proliferation is gradually inhibited, the pattern of P2 receptors is changed. This phenomenon is followed by diminishing of the P2Y2-dependent Ca2+ signaling, while the mRNA expression of P2Y2 receptor reminds still on the high level. Moreover, P2X2 receptor mRNA, absent in myoblasts appears in myotubes. These data show that differentiation of C2C12 cell line satellite myoblasts is accompanied by changes in P2 receptors expression pattern
The Role of N-Acetyltransferase 2 Polymorphism in the Etiopathogenesis of Inflammatory Bowel Disease
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