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18 pages, 2148 KiB  
Article
Nebivolol Polymeric Nanoparticles-Loaded In Situ Gel for Effective Treatment of Glaucoma: Optimization, Physicochemical Characterization, and Pharmacokinetic and Pharmacodynamic Evaluation
by Pradeep Singh Rawat, Punna Rao Ravi, Mohammed Shareef Khan, Radhika Rajiv Mahajan and Łukasz Szeleszczuk
Nanomaterials 2024, 14(16), 1347; https://doi.org/10.3390/nano14161347 - 14 Aug 2024
Viewed by 903
Abstract
Nebivolol hydrochloride (NEB), a 3rd-generation beta-blocker, was recently explored in managing open-angle glaucoma due to its mechanism of action involving nitric oxide release for the vasodilation. To overcome the issue of low ocular bioavailability and the systemic side effects associated with conventional ocular [...] Read more.
Nebivolol hydrochloride (NEB), a 3rd-generation beta-blocker, was recently explored in managing open-angle glaucoma due to its mechanism of action involving nitric oxide release for the vasodilation. To overcome the issue of low ocular bioavailability and the systemic side effects associated with conventional ocular formulation (aqueous suspension), we designed and optimized polycaprolactone polymeric nanoparticles (NEB-PNPs) by applying design of experiments (DoE). The particle size and drug loading of the optimized NEB-PNPs were 270.9 ± 6.3 nm and 28.8 ± 2.4%, respectively. The optimized NEB-PNPs were suspended in a dual-sensitive in situ gel prepared using a mixture of P407 + P188 (as a thermo-sensitive polymer) and κCRG (as an ion-sensitive polymer), reported previously by our group. The NEB-PNPs-loaded in situ gel (NEB-PNPs-ISG) formulation was characterized for its rheological behavior, physical and chemical stability, in vitro drug release, and in vivo efficacy. The NEB-PNPs-loaded in situ gel, in ocular pharmacokinetic studies, achieved higher aqueous humor exposure (AUC0–t = 329.2 ng × h/mL) and for longer duration (mean residence time = 9.7 h) than compared to the aqueous suspension of plain NEB (AUC0–t = 189 ng × h/mL and mean residence time = 6.1 h) reported from our previous work. The pharmacokinetic performance of NEB-PNPs-loaded in situ gel translated into a pharmacodynamic response with 5-fold increase in the overall percent reduction in intraocular pressure by the formulation compared to the aqueous suspension of plain NEB reported from our previous work. Further, the mean response time of NEB-PNPs-loaded in situ gel (12.4 ± 0.6 h) was three times higher than aqueous suspension of plain NEB (4.06 ± 0.3 h). Full article
(This article belongs to the Topic Advances in Controlled Release and Targeting of Drugs)
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<p>Three dimensional plots demonstrating the impact of significant factors on critical responses: (<b>a</b>) PS and (<b>b</b>) DL (%) for optimized NEB-PNPs.</p>
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<p>SEM image of the optimized NEB-PNPs.</p>
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<p>Semi-logarithmic plot of loss tangent versus temperature of the formulations. A—blank ISG; B—NEB-PNPs-ISG; and C—NEB-PNPs-ISG in the presence of STF.</p>
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<p>Drug-release profiles of NEB suspension, NEB-PNPs-Susp, and NEB-PNPs-ISG in the in vitro studies. The mean (±SD) of three replicate formulations (n = 3) is presented at each sampling point. Note: Data of NEB-Susp are from our previous published work [<a href="#B3-nanomaterials-14-01347" class="html-bibr">3</a>].</p>
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<p>Mean concentration of NEB versus time profiles constructed from the ocular administration of NEB-PNPs-Susp, NEB-PNPs-ISG, and NEB-Susp in aqueous humor. Note: Data of NEB-Susp are reproduced from our previous reported work [<a href="#B3-nanomaterials-14-01347" class="html-bibr">3</a>].</p>
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<p>Percent reduction in intra-ocular pressure (ΔIOP (%)) versus time plot of NEB-PNPs-Susp and NEB-PNPs-ISG administered through ocular route in rabbits (n = 6). Note: NEB-Susp profile is reproduced from our previous reported work [<a href="#B3-nanomaterials-14-01347" class="html-bibr">3</a>].</p>
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15 pages, 2672 KiB  
Article
Pathological Heart Rate Regulation in Apparently Healthy Individuals
by Ludmila Sidorenko, Irina Sidorenko, Andrej Gapelyuk and Niels Wessel
Entropy 2023, 25(7), 1023; https://doi.org/10.3390/e25071023 - 5 Jul 2023
Cited by 1 | Viewed by 1827
Abstract
Cardiovascular diseases are the leading cause of morbidity and mortality in adults worldwide. There is one common pathophysiological aspect present in all cardiovascular diseases—dysfunctional heart rhythm regulation. Taking this aspect into consideration for cardiovascular risk predictions opens important research perspectives, allowing for the [...] Read more.
Cardiovascular diseases are the leading cause of morbidity and mortality in adults worldwide. There is one common pathophysiological aspect present in all cardiovascular diseases—dysfunctional heart rhythm regulation. Taking this aspect into consideration for cardiovascular risk predictions opens important research perspectives, allowing for the development of preventive treatment techniques. The aim of this study was to find out whether certain pathologically appearing signs in the heart rate variability (HRV) of an apparently healthy person, even with high HRV, can be defined as biomarkers for a disturbed cardiac regulation and whether this can be treated preventively by a drug-free method. This multi-phase study included 218 healthy subjects of either sex, who consecutively visited the physician at Gesundheit clinic because of arterial hypertension, depression, headache, psycho-emotional stress, extreme weakness, disturbed night sleep, heart palpitations, or chest pain. In study phase A, baseline measurement to identify individuals with cardiovascular risks was done. Therefore, standard HRV, as well as the new cardiorhythmogram (CRG) method, were applied to all subjects. The new CRG analysis used here is based on the recently introduced LF drops and HF counter-regulation. Regarding the mechanisms of why these appear in a steady-state cardiorhythmmogram, they represent non-linear event-based dynamical HRV biomarkers. The next phase of the study, phase B, tested whether the pathologically appearing signs identified via CRG in phase A could be clinically influenced by drug-free treatment. In order to validate the new CRG method, it was supported by non-linear HRV analysis in both phase A and in phase B. Out of 218 subjects, the pathologically appearing signs could be detected in 130 cases (60%), p < 0.01, by the new CRG method, and by the standard HRV analysis in 40 cases (18%), p < 0.05. Thus, the CRG method was able to detect 42% more cases with pathologically appearing cardiac regulation. In addition, the comparative CRG analysis before and after treatment showed that the pathologically appearing signs could be clinically influenced without the use of medication. After treatment, the risk group decreased eight-fold—from 130 people to 16 (p < 0.01). Therefore, progression of the detected pathological signs to structural cardiac pathology or arrhythmia could be prevented in most of the cases. However, in the remaining risk group of 16 apparently healthy subjects, 8 people died due to all-cause mortality. In contrast, no other subject in this study has died so far. The non-linear parameter which is able to quantify the changes in CRGs before versus after treatment is FWRENYI4 (symbolic dynamic feature); it decreased from 2.85 to 2.53 (p < 0.001). In summary, signs of pathological cardiac regulation can be identified by the CRG analysis of apparently healthy subjects in the early stages of development of cardiac pathology. Thus, our method offers a sensitive biomarker for cardiovascular risks. The latter can be influenced by non-drug treatments (acupuncture) to stop the progression into structural cardiac pathologies or arrhythmias in most but not all of the patients. Therefore, this could be a real and easy-to-use supplemental method, contributing to primary prevention in cardiology. Full article
(This article belongs to the Special Issue Nonlinear Dynamics in Cardiovascular Signals)
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<p>Results of baseline cardiorhythmograms analysis by the physiological method (<b>left</b>) and by the standard linear HRV method (<b>right</b>). Based on this analysis, the individuals were divided in two groups: the healthy group and the group with recognized risks.</p>
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<p>Scheme of results obtained by applying the standard linear HRV method and the new physiological method of cardiorhythmogram analysis at every stage of the study: baseline measurement, after the treatment, and comparative analysis between both methods of analysis.</p>
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<p>Results of comparative analysis between the CRGs before and after the treatment course, evaluating the presence of pathological signs. The effectiveness of the treatment course is clearly visible. The number of patients belonging to the risk group is reduced by eight times—from 130 individuals divided into the risk group before the treatment, the number decreased after the treatment to 16 (<span class="html-italic">p</span> &lt; 0.01) individuals remaining in the risk group.</p>
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<p>Representative cardiorhythmograms of two individuals, measured at baseline before and after the treatment. The CRGs (<b>A</b>,<b>B</b>) belong to a patient in whose CRG the pathological signs disappeared after the treatment course. The CRGs (<b>C</b>,<b>D</b>) are from one of the 16 patients in who the pathological signs did not disappear after the treatment (deceased). Both (<b>A</b>,<b>C</b>) show pathological signs in the form of LF drops, followed by a pathological counter-regulation. After the treatment course in (<b>B</b>), the pathological signs disappeared. In (<b>D</b>), the pathological signs still remain.</p>
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<p>Steady-state cardiorhythmogram without events of non-stationarity, suitable for standard linear HRV analysis.</p>
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<p>Steady-state cardiorhythmograms where events of non-stationarity are presented. Cardiorhythmogram (<b>A</b>): the pathological signs are presented by the LF drops (encircled), but they are followed by a physiological counterbalancing via HF waves, so a low risk is estimated. Cardiorhythmogram (<b>B</b>): LF drops (encircled) are present followed by a pathological counter-regulation, predominant by LF waves, high risk is estimated.</p>
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20 pages, 55410 KiB  
Article
A New Graph-Based Fractality Index to Characterize Complexity of Urban Form
by Lei Ma, Stefan Seipel, Sven Anders Brandt and Ding Ma
ISPRS Int. J. Geo-Inf. 2022, 11(5), 287; https://doi.org/10.3390/ijgi11050287 - 28 Apr 2022
Cited by 5 | Viewed by 3487
Abstract
Examining the complexity of urban form may help to understand human behavior in urban spaces, thereby improving the conditions for sustainable design of future cities. Metrics, such as fractal dimension, ht-index, and cumulative rate of growth (CRG) index have been proposed to measure [...] Read more.
Examining the complexity of urban form may help to understand human behavior in urban spaces, thereby improving the conditions for sustainable design of future cities. Metrics, such as fractal dimension, ht-index, and cumulative rate of growth (CRG) index have been proposed to measure this complexity. However, as these indicators are statistical rather than spatial, they result in an inability to characterize the spatial complexity of urban forms, such as building footprints. To overcome this problem, this paper proposes a graph-based fractality index (GFI), which is based on a hybrid of fractal theory and deep learning techniques. First, to quantify the spatial complexity, several fractal variants were synthesized to train a deep graph convolutional neural network. Next, building footprints in London were used to test the method, where the results showed that the proposed framework performed better than the traditional indices, i.e., the index is capable of differentiating complex patterns. Another advantage is that it seems to assure that the trained deep learning is objective and not affected by potential biases in empirically selected training datasets Furthermore, the possibility to connect fractal theory and deep learning techniques on complexity issues opens up new possibilities for data-driven GIS science. Full article
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<p>Framework for characterizing complexity of building distributions.</p>
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<p>(color online) The statistical relationship between the number of squares, N, and scales, s, of the Sierpinski carpet and its variants (<b>a</b>); a Sierpinski carpet with the degree of dimensionality 4 (<b>b</b>) and a randomly synthesized variant (<b>c</b>), where the Ns are 1, 8, 75 and 500 for the red, green, blue and grey squares, respectively.</p>
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<p>(color online) Graph construction and representation for building groups: red lines are the TIN’s edges, blue lines show the distances, <math display="inline"><semantics> <mrow> <msub> <mi>d</mi> <mrow> <mi>i</mi> <mo>,</mo> <mi>m</mi> </mrow> </msub> </mrow> </semantics></math> to the neighbors, and every two red blocks constitute a two-dimensional vector <math display="inline"><semantics> <mrow> <msub> <mi>f</mi> <mi>i</mi> </msub> </mrow> </semantics></math> of node <math display="inline"><semantics> <mrow> <msub> <mi>v</mi> <mi>i</mi> </msub> </mrow> </semantics></math>.</p>
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<p>(color online) The DGCNN model maps graph representations to GFI. As an example, the figure highlights four vertices–A, B, C and D–and demonstrates how the GCN and SortPooling layers extract features. The scalars in brackets demonstrate how the dimensions of neuron matrices are defined in each layer. The parameter, k, defines the number of elements taken in account during the SortPooling operations.</p>
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<p>(color online) Examples of synthetic variants and the process of model training: (<b>a</b>) the uniform synthesis labeled as 1.0 and fractal variants with the dimensionality from level-2 to level-5 labeled from 2.0 to 5.0 individually and (<b>b</b>) the training loss, validating loss and accuracy of the training process over each epoch.</p>
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<p>(color online) The GFI distribution of building groups in the Greater London, intermediate zone and central core zone; more details are exhibited in the six magnified windows shown in the <b>1</b>–<b>6</b>.</p>
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<p>Distribution of GFI values in the Greater London, intermediate zone, and central core zone.</p>
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<p>(color online) Building footprints in neighborhood labeled by GFI: from the simple uniforms to complex fractals.</p>
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<p>(color online) Distributions between GFI and CRG-A (<b>a</b>), CRG-D (<b>b</b>) of the 34 examples shown in <a href="#ijgi-11-00287-t002" class="html-table">Table 2</a>; the outliers of CRG values are marked by the red circles.</p>
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17 pages, 3661 KiB  
Article
High-Resolution Representation for Mobile Mapping Data in Curved Regular Grid Model
by Jingxin Su, Ryuji Miyazaki, Toru Tamaki and Kazufumi Kaneda
Sensors 2019, 19(24), 5373; https://doi.org/10.3390/s19245373 - 5 Dec 2019
Cited by 5 | Viewed by 2854
Abstract
As mobile mapping systems become a mature technology, there are many applications for the process of the measured data. One interesting application is the use of driving simulators that can be used to analyze the data of tire vibration or vehicle simulations. In [...] Read more.
As mobile mapping systems become a mature technology, there are many applications for the process of the measured data. One interesting application is the use of driving simulators that can be used to analyze the data of tire vibration or vehicle simulations. In previous research, we presented our proposed method that can create a precise three-dimensional point cloud model of road surface regions and trajectory points. Our data sets were obtained by a vehicle-mounted mobile mapping system (MMS). The collected data were converted into point cloud data and color images. In this paper, we utilize the previous results as input data and present a solution that can generate an elevation grid for building an OpenCRG model. The OpenCRG project was originally developed to describe road surface elevation data, and also defined an open file format. As it can be difficult to generate a regular grid from point cloud directly, the road surface is first divided into straight lines, circular arcs, and and clothoids. Secondly, a non-regular grid which contains the elevation of road surface points is created for each road surface segment. Then, a regular grid is generated by accurately interpolating the elevation values from the non-regular grid. Finally, the curved regular grid (CRG) model files are created based on the above procedures, and can be visualized by OpenCRG tools. The experimental results on real-world data show that the proposed approach provided a very-high-resolution road surface elevation model. Full article
(This article belongs to the Section Remote Sensors)
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<p>The basic idea of the curved regular grid (CRG).</p>
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<p>Dataset obtained by mobile mapping system.</p>
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<p>The difference of point density according to the direction.</p>
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<p>The results of our previous work.</p>
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<p>A road image of left width, right width, and emergency lane.</p>
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<p>Processing workflow.</p>
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<p>Example of straight line and circular arc detection (<b>top</b>), and clothoid curve estimation (<b>bottom</b>).</p>
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<p>Approach for finding corresponding non-regular grid points (distance values in the figure are the unit distances).</p>
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<p>Bilinear interpolation.</p>
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<p>Comparison of non-regular and regular grids. Black dots are the non-regular grid points; red points are the estimated regular grid points.</p>
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<p>Example of a clothoid road segment visualization.</p>
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<p>Example of a circular road segment visualization.</p>
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<p>Example of a circular road segment visualization.</p>
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