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In the study of coronary artery disease (CAD), the mechanism of plaque formation and development is still an important subject for investigation. A limitation of current coronary angiography (CAG) is that it can only show static images of the narrowing of arterial channels without identifying the mechanism of the disease or predicting its progression or regression. To address this limitation, the CAG technique has been modified. The new approach emphasizes identifying and analyzing blood flow patterns, employing methodologies akin to those used by hydraulic engineers for fluid or gas movement through domestic or industrial pipes and pumps. With the new technique, various flow patterns and arterial phenomena—such as laminar, turbulent, antegrade, retrograde, and recirculating flow and potentially water hammer shock and vortex formation—are identified, recorded, and classified. These phenomena are then correlated with the presence of lesions at different locations within the coronary vasculature. The formation and growth of these lesions are explained from the perspective of fluid mechanics. As the pathophysiology of CAD and other cardiovascular conditions becomes clearer, new medical, surgical, and interventional treatments could be developed to reverse abnormal coronary flow dynamics and restore laminar flow, leading to improved clinical outcomes. [ABSTRACT FROM AUTHOR]

The reconstruction of soft tissue defects in the foot and ankle remains a big challenge due to the anatomical characteristics of this area. This study evaluated the long-term effectiveness of covering by lateral supramalleolar flap in patients with soft tissue defects around the ankle and foot. We conducted a retrospective study from January 2017 to December 2020 at the Hospital for Traumatology and Orthopedics, Ho Chi Minh City, Vietnam. Data about patients' characteristics, detailed injuries, perioperative information, intraprocedural dossier, and complications of this method were recorded and analyzed. There were 31 male and 17 female patients, with an average age of 39.8 (ranging from 11 to 77) years. The skin defects ranged from 8 cm2 to 120 cm2. The blood supply for the flap included a mixed-flow pattern (n = 30) and retrograde flow (n = 18). The success rate was 94%. Forty-two patients had been successfully covered, five patients had partial flap necrosis (in which two cases needed skin graft afterwards and three cases got spontaneous healing), only one patient had total flap necrosis. In conclusion, the lateral supramalleolar flap can cover the soft tissue of ankle and foot defects in both mixed-blood supply pattern or retrograde pattern with high success rates. However, the risk of venous congestion should be considered, particularly when using the retrograde pattern flap. [ABSTRACT FROM AUTHOR]

Cystic fibrosis is an autosomal recessive disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) that can lead to terminal respiratory failure. Ultrafine carbonaceous particles, which are ubiquitous in ambient urban and indoor air, are increasingly considered as major contributors to the global health burden of air pollution. However, their effects on the expression of CFTR and associated genes in lung epithelial cells have not yet been investigated. We therefore evaluated the effects of carbon nanoparticles (CNP), generated by spark-ablation, on the human bronchial epithelial cell line 16HBE14o− at air–liquid interface (ALI) culture conditions. The ALI-cultured cells exhibited epithelial barrier integrity and increased CFTR expression. Following a 4-h exposure to CNP, the cells exhibited a decreased barrier integrity, as well as decreased expression of CFTR transcript and protein levels. Furthermore, transcriptomic analysis revealed that the CNP-exposed cells showed signs of oxidative stress, apoptosis and DNA damage. In conclusion, this study describes spark-ablated carbon nanoparticles in a realistic exposure of aerosols to decrease CFTR expression accompanied by transcriptomic signs of oxidative stress, apoptosis and DNA damage. [ABSTRACT FROM AUTHOR]

The study aims to investigate the effect of formulation variables on the characteristics of azithromycin (AZI) nanoparticles using a quality by design approach. AZI nanoparticles were prepared by the emulsification solvent diffusion method. Two critical factors, the ratio of AZI: Eudragit EPO (X1) and volume of outer aqueous medium (X2), were chosen as independent variables for central composite design. The optimized formulation was further characterized by Fourier transform infrared spectroscopy, X-ray diffractometry, transmission electron microscopy, and dissolution test. The obtained results showed variability of mean particle size, entrapment efficacy, and zeta potential from 200 to 1232 nm, 10.78 to 75.9%, and 31 to 43 mV, respectively. The main coefficients indicated that the ratio of AZI: polymer (X1) possessed a synergistic effect on mean particle size (Y1), and volume of outer aqueous medium (X2) had an antagonistic effect on particle size. The interaction between the ratio of AZI: Eudragit EPO (X1) and volume of outer aqueous medium (X2) exhibited a significant antagonistic effect on entrapment efficacy (Y2) (p<0.05). AZI existed in an amorphous state in nanoparticles that were spherical and homogeneous in shape. The nanoparticles revealed the Korsmeyer-Peppas release model, from which AZI was released faster compared to raw material. [ABSTRACT FROM AUTHOR]

Background: Conformational transitions are implicated in the biological function of many proteins. Structural changes in proteins can be described approximately as the relative movement of rigid domains against each other. Despite previous efforts, there is a need to develop new domain segmentation algorithms that are capable of analysing the entire structure database efficiently and do not require the choice of protein-dependent tuning parameters such as the number of rigid domains. Results: We develop a graph-based method for detecting rigid domains in proteins. Structural information from multiple conformational states is represented by a graph whose nodes correspond to amino acids. Graph clustering algorithms allow us to reduce the graph and run the Viterbi algorithm on the associated line graph to obtain a segmentation of the input structures into rigid domains. In contrast to many alternative methods, our approach does not require knowledge about the number of rigid domains. Moreover, we identified default values for the algorithmic parameters that are suitable for a large number of conformational ensembles. We test our algorithm on examples from the DynDom database and illustrate our method on various challenging systems whose structural transitions have been studied extensively. Conclusions: The results strongly suggest that our graph-based algorithm forms a novel framework to characterize structural transitions in proteins via detecting their rigid domains. The web server is available at http://azifi.tz.agrar.uni-goettingen.de/webservice/. [ABSTRACT FROM AUTHOR]

• DoE-based approach is useful to optimize the formulation of microemulsion. • Carboxymethyl cellulose is chosen as optimal hydrogel-forming agent. • Anti-inflammatory effect of ME-hydrogel is higher than SLN-hydrogel, NLC-hydrogel. This study was performed to achieve two primary goals: First, a microemulsion containing betamethasone dipropionate was optimized using the quality by design approach. Second, a hydrogel-containing microemulsion was developed using cellulose derivatives, and its anti-inflammatory and skin irritation effects were evaluated. Face-centered central composite design was used to investigate the impacts of two independent variables (oleic acid and ratio of surfactant to cosolvent, S/CoS) on three dependent variables (skin deposition, flux of BMD, and microemulsion droplet size). The microemulsion including oleic acid at a low level (coded with -1) and S/CoS at a high level (coded with +1) was considered optimal since it was the most effective in terms of skin deposition and flux of BMD. Different cellulose derivatives (HPMC E6, HEC, NaCMC, and CMC) were screened to prepare a hydrogel-containing microemulsion based on four properties: flux and skin deposition of BMD, hydration of stratum corneum, and rheological properties of hydrogel-containing microemulsion (ME-hydrogel). The anti-inflammatory effect and flux of BMD from optimal ME-hydrogel with carboxymethyl cellulose as the hydrogel-forming agent were then compared to those of the hydrogel-containing solid lipid nanoparticles (SLN-hydrogel) and nanostructure lipid carriers (NLC-hydrogel). The percentage of edema inhibition declined proportionally with flux of BMD in the following order: ME-hydrogel (44.56 ± 8.08%) > NLC-hydrogel (35.93 ± 7.22%) > SLN-hydrogel (25.68 ± 9.05%). [ABSTRACT FROM AUTHOR]

A 22-year-old woman with myasthenia gravis (MG) presented with ptosis and mild muscle weakness symptoms for one year. Computed tomography (CT) presented a diffuse bilobulate enlargement gland with a high density of soft tissue. Magnetic resonance imaging (MRI) showed the gland with no suppression on the opposed-phase chemical shift. After the thymic tumor diagnosis, she underwent thoracoscopic surgery for tumor resection. The postoperative histopathological finding was thymic lymphoid hyperplasia. This case suggests chemical shift MRI is not enough in distinguishing, and supplementary examination is essential to avoid unnecessary thymic biopsy and surgery. [ABSTRACT FROM AUTHOR]

Motivation: Large-scale conformational changes in proteins are implicated in many important biological functions. These structural transitions can often be rationalized in terms of relative movements of rigid domains. There is a need for objective and automated methods that identify rigid domains in sets of protein structures showing alternative conformational states. Results: We present a probabilistic model for detecting rigid-body movements in protein structures. Our model aims to approximate alternative conformational states by a few structural parts that are rigidly transformed under the action of a rotation and a translation. By using Bayesian inference and Markov chain Monte Carlo sampling, we estimate all parameters of the model, including a segmentation of the protein into rigid domains, the structures of the domains themselves, and the rigid transformations that generate the observed structures. We find that our Gibbs sampling algorithm can also estimate the optimal number of rigid domains with high efficiency and accuracy. We assess the power of our method on several thousand entries of the DynDom database and discuss applications to various complex biomolecular systems. [ABSTRACT FROM AUTHOR]

There has been a great scientific interest in exploring the great potential of the piperazine-phosphonates in flame retardant (FR) application on cotton fabric by investigating the thermal decomposition of cotton fabric treated with them. This research tries to understand the mode of action of the two piperazine-phosphonates derivatives on cotton fabric. The investigation proceeds by preparing Tetraethyl piperazine-1,4-diyldiphosphonate ( TEPP) and Diethyl 4-methyl piperazin-1-ylphosphoramidate ( DEPP ), engrafting them on cotton fabric and studying their mechanism of thermal degradation on fabric. In studying the mechanism, we learned the chemical functional groups of the chemicals on the surface of the treated fabrics and of the evolved gases produced thermogravimetrically and pyrolytically by using different analytical techniques such as attenuated total reflection infrared (ATR-IR), thermogravimetric analysis–Fourier transform infrared (TGA–FTIR) spectroscopy and pyrolysis-gas chromatography–mass spectrometry (Py-GC/MS). The experiment's results showed some distinctive details in the thermal degradation of the fabric when applied with these additives. [ABSTRACT FROM AUTHOR]

There isa lack of evidence from randomized clinical trials (RCT) supporting percutaneous coronary intervention (PCI) in patients with high bleeding risk or active bleeding. The management decisions are based on extrapolation of subgroups data in RCTs or experts' opinions. Bleeding in the peri-PCI period also increases mortality. In general, PCI can be performed if bleeding can be stopped by mechanical means (compressing or ligating the artery) and the patient can tolerate 4 hours of anticoagulant without further bleeding. For patient with acquired or inherited high risk of bleeding, anecdotal reports showed that either unfractionated heparin or bivalirudin would be acceptable for PCI. For patients on chronic oral anticoagulants, PCI could be performed without new antithrombotic therapy if the international ratio (INR) is between 2 and 3. Antiplatelet therapy would be needed if new thrombi are detected at the index artery. Ultimately, the decision to perform PCI or treat the patient conservatively must be managed on a case-by-case basis. If the benefits outweigh the risk, then the patient can undergo PCI. (Anadolu Kardiyol Derg 2013; 13:165-70) [ABSTRACT FROM AUTHOR]

Harnessing non-spatial properties of photons as if they represent an additional independent coordinate underpins the emerging synthetic dimension approach. It enables probing of higher-dimensional physical models within low-dimensional devices, such as on a planar chip where this method is relatively nascent. We demonstrate an integrated thin-film lithium niobate ring resonator that, under dynamic modulation, simulates a tight-binding model with its discrete frequency modes representing lattice sites. Inter-mode coupling, and the simulated lattice geometry, can be reconfigured by controlling the modulating signals. Up to a quasi-3D lattice connectivity with controllable gauge potentials has been achieved by simultaneous synchronized nearest-, second- and third-nearest-neighbor coupling, and verified by acquiring synthetic band structures. Development of synthetic frequency dimension devices in the thin-film lithium niobate photonic integration platform is a key step in increasing the complexity of topological models achievable on a chip, combining efficient electro-optic mode coupling with non-linear effects for long-range mode interactions. Lithium niobate on insulator (LNOI) is emerging as a powerful photonic integration platform for synthetic dimension approaches that enable probing of higher-dimensional physical models within low-dimensional devices. The authors present a LNOI ring device, whose frequency modes represent lattice sites for versatile simulation of tight-binding models with up to three-dimensional connectivity. [ABSTRACT FROM AUTHOR]

Objectives Influenza A/H1N1pdm09 virus was first detected in Vietnam on May 31, 2009, and continues to circulate in Vietnam as a seasonal influenza virus. This study has monitored genotypic and phenotypic changes in this group of viruses during 2010-2013 period. Design and setting We sequenced hemagglutinin ( HA) and neuraminidase ( NA) genes from representative influenza A/H1N1pdm09 and compared with vaccine strain A/California/07/09 and other contemporary isolates from neighboring countries. Hemagglutination inhibition ( HI) and neuraminidase inhibition ( NAI) assays also were performed on these isolates. Sample Representative influenza A/H1N1pdm09 isolates ( n = 61) from ILI and SARI surveillances in northern Vietnam between 2010 and 2013. Main outcome measures and results The HA and NA phylogenies revealed six and seven groups, respectively. Five isolates (8·2%) had substitutions G155E and N156K in the HA, which were associated with reduced HI titers by antiserum raised against the vaccine virus A/California/07/2009. One isolate from 2011 and one isolate from 2013 had a predicted H275Y substitution in the neuraminidase molecule, which was associated with reduced susceptibility to oseltamivir in a NAI assay. We also identified a D222N change in the HA of a virus isolated from a fatal case in 2013. Conclusions Significant genotypic and phenotypic changes in A/ H1N1pdm09 influenza viruses were detected by the National Influenza Surveillance System ( NISS) in Vietnam between 2010 and 2013 highlighting the value of this system to Vietnam and to the region. Sustained NISS and continued virological monitoring of seasonal influenza viruses are required for vaccine policy development in Vietnam. 3 [ABSTRACT FROM AUTHOR]