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1.
Heliyon ; 10(5): e26628, 2024 Mar 15.
Article En | MEDLINE | ID: mdl-38439831

The endoscopy of a coronary arterial segment having a symmetric emergence of plaque at its innermost region is numerically modeled via computational fluid dynamics toolbox Open-FOAM. The considered left coronary artery for this model has a radius of 2 mm and span of 10 mm. The formation of plaque inside the artery that is a stenosis has length 2 mm and height 0.82 mm. The catheter used for this analysis has a diameter of 1 mm with a balloon over it with a height of 0.53 mm. The blood flow rate considered for this analysis has a range 2.00 ml/s to 2.50 ml/s. The fluid under consideration for this endoscopy review is the non-Newtonian Casson model. The mesh illustrations are arranged for the proposed model with numerical simulations of velocity, pressure profile and streamlines. The narrow channel formed due to assembly of stenosis and balloon over catheter inside this arterial segment has developed some swirling flow profile with turbulence effects just after the flow leaves the stenosis plus balloon region. Although this disturbance caused due to narrowing of channel has made the flow slightly turbulent, the flow eventually leaves the arterial segment again as a laminar flow. To cure coronary artery disease, catheterization, and balloon dilation of stenosed arteries is performed to locate the position and shape of stenosis. A catheter is inserted inside the body through a minor cut and then it is moved inside arteries to place it exactly at the stenosis location. A balloon is placed at front of that catheter and the stenosed region can be opened wide by using balloon dilation.

2.
Am J Psychoanal ; 84(1): 1-15, 2024 Mar.
Article En | MEDLINE | ID: mdl-38461336

Three links between poetry and psychoanalysis are highlighted in this paper. These refer to the presence, in the clinical hour, of (i) poetic sentiment, (ii) poetic speech, and (iii) poetic specimen. Each is elucidated in detail and with the help of socio-clinical vignettes. The aim of the paper is to demonstrate that, through the affirmative holding and partial unmasking of the instinctual-epistemic conflation in verse and free-association, both poetry and psychoanalysis seek to transform the private into shared, the hideous into elegant, and the unfathomable into accessible.


Psychoanalysis , Speech , Humans , Free Association , Attitude
3.
Mol Biol Rep ; 51(1): 337, 2024 Feb 23.
Article En | MEDLINE | ID: mdl-38393520

The protein encoded by the ephrin type-A receptor 2 (EphA2) gene is a member of the ephrin receptor subfamily of the receptor tyrosine kinase family (RTKs). Eph receptors play a significant role in various biological processes, particularly cancer progression, development, and pathogenesis. They have been observed to regulate cancer cell growth, migration, invasion, tumor development, invasiveness, angiogenesis, and metastasis. To target EphA2 activity, various molecular, genetic, biochemical, and pharmacological strategies have been extensively tested in laboratory cultures and animal models. Notably, drugs, such as dasatinib, initially designed to target the kinase family, have demonstrated an additional capability to target EphA2 activity. Additionally, a novel monoclonal antibody named EA5 has emerged as a promising option to counteract the effects of EphA2 overexpression and restore tamoxifen sensitivity in EphA2-transfected MCF-7 cells during in vitro experiments. This antibody mimicked the binding of Ephrin A to EphA2. These methods offer potential avenues for inhibiting EphA2 activity, which could significantly decelerate breast cancer progression and restore sensitivity to certain drugs. This review article comprehensively covers EphA2's involvement in multiple malignancies, including ovarian, colorectal, breast, lung, glioma, and melanoma. Furthermore, we discuss the structure of EphA2, the Eph-Ephrin signaling pathway, various EphA2 inhibitors, and the mechanisms of EphA2 degradation. This article provides an extensive overview of EphA2's vital role in different types of cancers and outlines potential therapeutic approaches to target EphA2, shedding light on the underlying molecular mechanisms that make it an attractive target for cancer treatment.


Neoplasms , Receptor, EphA2 , Animals , Receptor, EphA2/genetics , Receptor, EphA2/metabolism , Neoplasms/drug therapy , Neoplasms/genetics , Receptor Protein-Tyrosine Kinases/metabolism , Signal Transduction , Ephrins/pharmacology , Cell Line, Tumor
4.
J Biomol Struct Dyn ; : 1-23, 2023 Nov 03.
Article En | MEDLINE | ID: mdl-37921704

Non-small cell lung cancer, head and neck cancer, glioblastoma, and various other cancer types often demonstrate persistent elevation in EGFR tyrosine kinase activity due to acquired mutations in its kinase domain. Any alteration in the EGFR is responsible for triggering the upregulation of tumor angiogenic pathways, such as the PI3k-AKT-mTOR pathway, MAPK-ERK pathway and PLC-Ƴ pathway, which are critically involved in promoting tumor angiogenesis in cancer cells. The emergence of frequently occurring EGFR kinase domain mutations (L858R/T790M/C797S) that confer resistance to approved therapeutic agents has presented a significant challenge for researchers aiming to develop effective and well-tolerated treatments against tumor angiogenesis. In this study, we directed our efforts towards the rational design and development of novel quinazoline derivatives with the potential to act as antagonists against both wild-type and mutant EGFR. Our approach encompasing the application of advanced drug design strategies, including structure-based virtual screening, molecular docking, molecular dynamics, metabolic reactivity and cardiotoxicity prediction studies led to the identification of two prominent lead compounds: QU648, for EGFRwt inhibition and QU351, for EGFRmt antagonism. The computed binding energies of selected leads and their molecular dynamics simulations exhibited enhanced conformational stability of QU648 and QU351 when compared to standard drugs Erlotinib and Afatinib. Notably, the lead compounds also demonstrated promising pharmacokinetic properties, metabolic reactivity, and cardiotoxicity profiles. Collectively, the outcomes of our study provide compelling evidence supporting the potential of QU648 and QU351 as prominent anti-angiogenic agents, effectively inhibiting EGFR activity across various cancer types harboring diverse EGFR mutations.Communicated by Ramaswamy H. Sarma.

5.
Sci Rep ; 13(1): 16389, 2023 Sep 29.
Article En | MEDLINE | ID: mdl-37773182

The current work deals with the oblique stagnation point flow phenomenon of a rate-type Maxwell fluid with the significance of the Cattaneo-Christov double diffusion theory. The Cattaneo-Christov theory is illustrated through the modified form of Fourier's and Fick's laws. The steady magnetized flow mechanism is observed in two dimensions through a stretchable convective Riga plate. In the mass and heat transfer analysis, the consequences of chemical reactions and thermal radiation are also incorporated. With the contribution of relevant dimensionless quantities, the setup of dimensionless equations is acquired which further takes the form of nonlinear equations. The physical significance of the numerous parameters on different features of the flow phenomenon is graphically exhibited. The interesting physical quantities are computed and numerically evaluated relative to the pertinent parameters. This study reveals that the thermal relaxation time parameter lowers the rate of heat transfer, and the thermal Biot number enhances the rate of heat transport. Moreover, the Deborah number minimizes the flow field of both tangential and axial velocities.

6.
Sci Prog ; 106(2): 368504231180092, 2023.
Article En | MEDLINE | ID: mdl-37292014

This research article interprets the computational fluid dynamics analysis on blood flow inside a symmetric stenosed artery. The current problem models the blood flow inside the left coronary artery as having a symmetric stenosis in the central region. A comprehensive physiological examination of coronary artery disease is numerically evaluated by using the computational fluid dynamics toolbox Open-Field Operation And Manipulation. There are no assumptions of mild stenosis taken into account since the considered stenosis has an exactly measured length, height and position, etc. The blood flow problem is modeled for the non-Newtonian Casson fluid with unsteady, laminar, and incompressible flow assumptions. The underlying problem is solved numerically in its dimensional form. A thorough graphical analysis is provided on the blood flow simulations, pressure profile, velocity line graphs, pressure line graphs, and streamlines for the left coronary artery having a symmetric stenosis formation. The considered artery is divided into three sections, i.e. pre-stenosis, post-stenosis, and stenosis region, and the velocity and pressure line graphs are plotted for these considered regions. The graphical illustrations provide a detailed analysis of how the blood flow is affected inside the left coronary artery due to coronary artery disease. These pre- and post-stenosis velocity line graphs reveal two intriguing results: In the pre-stenosis zone, the velocity increases with increasing axial coordinate length, whereas in the post-stenosis region, the velocity decreases with rising axial coordinate length. It is evident that as the flow moves toward the stenosis region, the flow profile rises; yet, after passing through the stenosis zone, the flow profile begins to fall as the flow moves away from the stenosis region.


Coronary Artery Disease , Coronary Stenosis , Humans , Constriction, Pathologic , Computer Simulation , Models, Cardiovascular
7.
Sci Rep ; 13(1): 1504, 2023 Jan 27.
Article En | MEDLINE | ID: mdl-36707684

Entropy interpretation with a descriptive heat generation analysis is carried out for the heated flow between two homocentric and sinusoidally fluctuating curved tubes. A novel peristaltic endoscope is considered for the first time inside a curved tube with evaluation of heat transfer and entropy. This flexible and novel endoscope with peristaltic locomotion is more efficient for endoscopy of complex mechanical structures and it is more comfortable for patients undergoing the endoscopy of a human organs. A comprehensive mathematical model is developed that also completely evaluates the heat transfer analysis for this novel endoscope. Certain and systematic computations are performed with the help of Mathematica software and exact mathematical as well as graphical solutions are obtained. Entropy has a lower rate that is almost zero entropy in the central region of these two curved tubes, but maximum entropy is noted near the sinusoidally deformable walls of both the endoscope and channel.

8.
Curr Med Chem ; 30(3): 271-285, 2023.
Article En | MEDLINE | ID: mdl-35692148

BACKGROUND: Even though the battle against one of the deadliest diseases, cancer, has advanced remarkably in the last few decades and the survival rate has improved significantly; the search for an ultimate cure remains a utopia. Nanoinformatics, which is bioinformatics coupled with nanotechnology, endows many novel research opportunities in the preclinical and clinical development of personalized nanosized drug carriers in cancer therapy. Personalized nanomedicines serve as a promising treatment option for cancer owing to their noninvasiveness and their novel approach. Explicitly, the field of personalized medicine is expected to have an enormous impact soon because of its many advantages, namely its versatility to adapt a drug to a cohort of patients. OBJECTIVE: The current review explains the application of this newly emerging field called nanoinformatics to the field of precision medicine. This review also recapitulates how nanoinformatics could hasten the development of personalized nanomedicine for cancer, which is undoubtedly the need of the hour. CONCLUSION: This approach has been facilitated by a humongous impending field named Nanoinformatics. These breakthroughs and advances have provided insight into the future of personalized medicine. Imperatively, they have been enabling landmark research to merge all advances, creating nanosized particles that contain drugs targeting cell surface receptors and other potent molecules designed to kill cancerous cells. Nanoparticle- based medicine has been developing and has become a center of attention in recent years, focusing primely on proficient delivery systems for various chemotherapy drugs.


Neoplasms , Precision Medicine , Humans , Neoplasms/drug therapy , Computational Biology , Drug Carriers , Nanomedicine , Drug Delivery Systems
9.
Sci Rep ; 12(1): 12943, 2022 Jul 28.
Article En | MEDLINE | ID: mdl-35902642

In this research, we have considered the convective heat transfer analysis on peristaltic flow of Rabinowitsch fluid through an elliptical cross section duct. The Pseudoplastic and Dilatant characteristics of non-Newtonian fluid flow are analyzed in detail. The Rabinowitsch fluid model shows Pseudoplastic fluid nature for [Formula: see text] and Dilatant fluid behaviour for [Formula: see text] The governing equations are transformed to dimensionless form after substituting pertinent parameters and by applying the long wavelength approximation. The non-dimensional momentum and energy equations are solved analytically to obtain the exact velocity and exact temperature solutions of the flow. A novel polynomial of order six having ten constants is introduced first time in this study to solve the energy equation exactly for Rabinowitsch fluid flow through an elliptic domain. The analytically acquired solutions are studied graphically for the effective analysis of the flow. The flow is found to diminish quickly in the surrounding conduit boundary for Dilatant fluid as compared to the Pseudoplastic fluid. The temperature depicted the opposite nature for Pseudoplastic and Dilatant fluids. The flow is examined to plot the streamlines for both Pseudoplastic and Dilatant fluids by rising the flow rate.

10.
Sci Prog ; 105(2): 368504221096000, 2022.
Article En | MEDLINE | ID: mdl-35491727

In this research, the electro-osmotic effects are highlighted for a blood-based hybrid nanofluid flow across an artery infected with multiple stenosis. The artery has permeable walls together with slip boundary effects. The slip and permeable boundary conditions model the more realistic blood flow problems. The governing equations of the problem are converted into non-dimensional form by introducing adequate dimensionless variables and acquired the exact solutions. The detailed study of heat transfer is given by Joule heating and viscous dissipation effects. The disorder of fluid flow is investigated by the mathematical study of entropy generation. Analytically attained solutions are examined graphically for both symmetric and non-symmetric shapes of stenosis. Streamlines are analyzed for varying values of flow rate Q and electro-osmotic parameter m. The flow velocity has smallest values on the axis of channel and gets higher value near the boundary walls. The temperature profile delineates opposite behavior to the velocity, and it is parabolic in nature. The velocity reduces towards the non-uniform stenosis except for electroosmotic parameter m. The temperature has larger magnitude in the case of anti-symmetric stenosis. Moreover, the stability of velocity solution is also analyzed.


Hemodynamics , Nanoparticles , Arteries , Constriction, Pathologic , Entropy , Humans
11.
Radiol Technol ; 93(4): 368-377, 2022 03.
Article En | MEDLINE | ID: mdl-35260485

PURPOSE: To evaluate the effect of physician and nonphysician cardiac catherization laboratory personnel on the treatment of myocardial infarction. METHODS: Admissions data from 4 Las Vegas, Nevada hospitals were analyzed via multivariate regression analysis to determine predictors of reperfusion times. The goal for reperfusion is a door-to-balloon time of less than 90 minutes. RESULTS: Prehospital ST-segment elevation myocardial infarction (STEMI) activation, cardiologist arrival time, lifesaving measures, door-to-electrocardiogram (ECG) time, time and day, critical diagnostic examinations, and door-to-first-medical-doctor time all significantly affected door-to-balloon time. However, cardiac catheterization laboratory (CCL) staff arrival time did not affect door-to-balloon time. DISCUSSION: This study confirms the well-established importance of prehospital ECG and STEMI protocol activation. The results also indicate the importance of cardiologist arrival time on reperfusion times as this explained a significant amount of the explained variance in door-to-balloon time. CCL team arrival time did not affect door-to-balloon time, dispelling a long-held belief that reducing the response time of the CCL team significantly reduced reperfusion times. CONCLUSION: Although cardiologist arrival time influenced door-to-balloon time, CCL staff arrival time did not. Programs to provide greater laboratory coverage might help improve reperfusion times as well as assist STEMI program coordinators in developing more efficient protocols.


Angioplasty, Balloon, Coronary , Myocardial Infarction , Angioplasty, Balloon, Coronary/methods , Cardiac Catheterization , Electrocardiography , Emergency Service, Hospital , Humans , Myocardial Infarction/therapy , Time Factors , Time-to-Treatment
12.
J Biomol Struct Dyn ; 40(20): 9815-9832, 2022.
Article En | MEDLINE | ID: mdl-34151738

Cyclin-dependent kinases are of critical importance in directing various cell cycle phases making them as potential tumor targets. Cyclin-dependent kinase 2 (CDK2) in particular plays a significant part during cell cycle events and its imbalance roots out tumorogenic environment. Herein, we built a structure-based pharmacophore model complementing the ATP pocket site of CDK2 with four pharmacophoric features, using a series of structures obtained from cluster analysis during MD simulation assessment. This was followed by its validation and further database screening against Taiwan indigenous plants database (5284 compounds). The screened compounds were subjected toward Lipinski's rule (RO5) and ADMET filter followed by docking analysis and simulation study. In filtering hits (10 compounds) via molecular docking against CDK2, Schinilenol with -8.1 kcal/mol fetched out as a best lead phytoinhibitor in the presence of standard drug (Dinaciclib). Additionally, pharmacophore mapping analysis also indicated relative fit values of dinaciclib and schinilenol as 2.37 and 2.31, respectively. Optimization, flexibility prediction and the stability of CDK2 in complex with the ligands were also ascertained by means of molecular dynamics for 50 ns, which further proposed schinilenol having better binding stability than dinaciclib with RMSD values ranging from 0.31 to 0.34 nm. Reactivity site, biological activity detection and cardiotoxicity assessment also proposed schinilenol as a better phytolead inhibitor than the existing dinaciclib. Abbreviations: CDK2: Cyclin dependent kinase2; ATP: Adenosine triphosphate; MD: Molecular dynamics, RO5: Rule of five; ADMET: Absorption, distribution, metabolism, and excretion; RMSD: Root mean square deviation; DS: Discovery Studio; SOM: Site of metabolism; RBPM: receptor based pharmacophore model; TIP: Schinilenol; hERG: human Ether-à-go-go - Related GeneCommunicated by Ramaswamy H. Sarma.


Cyclin-Dependent Kinase 2 , Pharmacophore , Protein Kinase Inhibitors , Humans , Adenosine Triphosphate , Cyclin-Dependent Kinase 2/antagonists & inhibitors , Hydrogen Bonding , Ligands , Molecular Docking Simulation , Molecular Dynamics Simulation , Phytochemicals/pharmacology , Protein Kinase Inhibitors/chemistry , Quantitative Structure-Activity Relationship
13.
Front Biosci (Landmark Ed) ; 26(10): 851-865, 2021 10 30.
Article En | MEDLINE | ID: mdl-34719210

Alzheimer's, a progressive neurodegenerative disease affects brain and neurons through enormous reduction in nerve cell regenerative capacity. Dementia and impairment of cognitive functions are more prevalent in Alzheimer's disease (AD) patients in both industrialized and non-industrialized countries. Various factors play significant role in molecular cascades that leads to neuronal inflammation, dementia and thereby AD progression. Current medications are symptomatic that alleviates pain while lack in absolute cure, urging researchers to explore targets and therapeutics. Interestingly, nanomedicines developed due to the onset of nanotechnology, are being extensively investigated for the treatment of AD. This review presents the advancement in nanotherapeutic strategies, involving the emergence of nanomaterials that offers advantage to pass through the blood-brain barrier and acts as a therapeutic modality against AD.


Alzheimer Disease , Nanostructures , Neurodegenerative Diseases , Alzheimer Disease/drug therapy , Blood-Brain Barrier , Brain , Humans
14.
Sci Prog ; 104(4): 368504211050292, 2021 Oct.
Article En | MEDLINE | ID: mdl-34738839

In this study, "peristaltic transport of hybrid nanofluid" inside a rectangular duct is examined. Water (base fluid) is used with two types of nanoparticles, namely, single-walled carbon nanotube (SWCNT) and multi-walled carbon nanotube (MWCNT). The viscous dissipation effect comes out as the prime heat generation source as compared to the conduction of molecules. After using some suitable dimensionless quantities, we obtained the nonlinear partial differential equations in a coupled form which are then solved exactly by the Eigenfunction expansion method. Velocity distribution, pressure gradient, and pressure rise phenomena are also discussed graphically through effective physical parameters. The heat transfer rate is high for the phase flow (single-walled carbon nanotube/water) model as compared to the hybrid (single-walled carbon nanotube + multi-walled carbon nanotube/water) model due to the enhanced thermal conductivity of the hybrid model.

15.
Entropy (Basel) ; 23(6)2021 Jun 09.
Article En | MEDLINE | ID: mdl-34207522

Peristaltic flow of hybrid nanofluid inside a duct having sinusoidally advancing boundaries and elliptic cross-section is mathematically investigated. The notable irreversibility effects are also examined in this mathematical research by considering a descriptive entropy analysis. In addition, this work provides a comparison analysis for two distinct nanofluid models: a hybrid model (Cu-Ag/water) and a phase flow model (Cu/water). A comprehensive graphical description is also provided to interpret the physical aspects of this mathematical analysis.

16.
Sci Prog ; 104(3): 368504211031693, 2021.
Article En | MEDLINE | ID: mdl-34296626

The electro-osmotically modulated hemodynamic across an artery with multiple stenosis is mathematically evaluated. The non-Newtonian behaviour of blood flow is tackled by utilizing Casson fluid model for this flow problem. The blood flow is confined in such arteries due to the presence of stenosis and this theoretical analysis provides the electro-osmotic effects for blood flow through such arteries. The mathematical equations that govern this flow problem are converted into their dimensionless form by using appropriate transformations and then exact mathematical computations are performed by utilizing Mathematica software. The range of the considered parameters is given as 0.03<δl<0.12,2

Arteries , Hemodynamics , Constriction, Pathologic , Electroosmosis , Hemodynamics/physiology , Humans , Viscosity
17.
Sci Rep ; 11(1): 15124, 2021 07 23.
Article En | MEDLINE | ID: mdl-34302050

Viscous flow between two sinusoidally deforming curved concentric tubes is mathematically investigated for the first time. Exact solutions are computed to analyse the flow between these two tubes and graphical outcomes are included for a thorough analysis of the solutions. The present article has prime applications in endoscopy as a novel peristaltic endoscope is introduced first time for a curved sinusoidal tube. This curved nature of outer sinusoidal tube with a flexible peristaltic endoscope placed inside it covers the topic of practical applications like endoscopy of human organs having curved shapes and the maintenance of complex machineries that involve complex curve structures. The usage of a flexible peristaltic endoscope inside a curved sinusoidal tube makes the process of catheterization more comfortable.

18.
Sci Prog ; 104(2): 368504211023683, 2021.
Article En | MEDLINE | ID: mdl-34100327

A mathematical model is presented to analyse the flow characteristics and heat transfer aspects of a heated Newtonian viscous fluid with single wall carbon nanotubes inside a vertical duct having elliptic cross section and sinusoidally fluctuating walls. Exact mathematical computations are performed to get temperature, velocity and pressure gradient expressions. A polynomial solution technique is utilized to obtain these mathematical solutions. Finally, these computational results are presented graphically and different characteristics of peristaltic flow phenomenon are examined in detail through these graphs. The velocity declines as the volume fraction of carbon nanotubes increases in the base fluid. Since the velocity of fluid is dependent on its temperature in this study case and temperature decreases with increasing volumetric fraction of carbon nanotubes. Thus velocity also declines for increasing volumetric fraction of nanoparticles.

19.
Sci Rep ; 11(1): 6718, 2021 03 24.
Article En | MEDLINE | ID: mdl-33762650

The blood flow inside a tube with multi-thromboses is mathematically investigated. The existence of these multiple thromboses restricts the blood flow in this tube and the flow is revamped by using a catheter. This non-Newtonian blood flow problem is modeled for Jeffrey fluid. The energy equation includes a notable effect of viscous dissipation. We have calculated an exact solution for the developed mathematical governing equations. These mathematical equations are solved directly by using Mathematica software. The graphical outcomes are added to discuss the results in detail. The multiple thromboses with increasing heights are evident in streamline graphs. The sinusoidally advancing wave revealed in the wall shear stress graphs consists of crest and trough with varying amplitude. The existence of multi-thrombosis in this tube is the reason for this distinct amplitude of crest and trough. Further, the viscous dissipation effects come out as a core reason for heat production instead of molecular conduction.

20.
Comput Methods Biomech Biomed Engin ; 24(3): 289-298, 2021 Feb.
Article En | MEDLINE | ID: mdl-33508967

A comprehensive mathematical model is presented to study the peristaltic flow of Bingham viscoplastic micropolar fluid flow inside a microlength channel with electro-osmotic effects. The electro-osmotic effects are produced due to an axially applied electric field. The circulation of this electric potential is calculated by utilizing Poisson Boltzmann equation. The dimensionless form of mathematical equations is obtained by using lubrication theory and Debye-Huckel approximation. We have obtained analytical solutions for the final dimensionless governing equations. Finally, the graphical results are added to further discuss the physical aspects of the problem. Electro-osmotic is mainly helping to control the flow and axial velocity decreases with an increase in the electric field but micro-angular velocity increases with an increase in electric field.


Computational Biology , Electroosmosis , Rheology , Stomach/anatomy & histology , Models, Theoretical , Pressure , Stress, Mechanical , Viscosity
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