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1.
Comput Methods Programs Biomed ; 253: 108249, 2024 Aug.
Article En | MEDLINE | ID: mdl-38815528

BACKGROUND AND OBJECTIVE: Automatic electrocardiogram (ECG) signal analysis for heart disease detection has gained significant attention due to busy lifestyles. However, ECG signals are susceptible to noise, which adversely affects the performance of ECG signal analysers. Traditional blind filtering methods use predefined noise frequency and filter order, but they alter ECG biomarkers. Several Deep Learning-based ECG noise detection and classification methods exist, but no study compares recurrent neural network (RNN) and convolutional neural network (CNN) architectures and their complexity. METHODS: This paper introduces a knowledge-based ECG filtering system using Deep Learning to classify ECG noise types and compare popular computer vision model architectures in a practical Internet of Medical Things (IoMT) framework. Experimental results demonstrate that the CNN-based ECG noise classifier outperforms the RNN-based model in terms of performance and training time. RESULTS: The study shows that AlexNet, visual geometry group (VGG), and residual network (ResNet) achieved over 70% accuracy, specificity, sensitivity, and F1 score across six datasets. VGG and ResNet performances were comparable, but VGG was more complex than ResNet, with only a 4.57% less F1 score. CONCLUSIONS: This paper introduces a Deep Learning (DL) based ECG noise classifier for a knowledge-driven ECG filtering system, offering selective filtering to reduce signal distortion. Evaluation of various CNN and RNN-based models reveals VGG and Resnet outperform. Further, the VGG model is superior in terms of performance. But Resnet performs comparably to VGG with less model complexity.


Deep Learning , Electrocardiography , Neural Networks, Computer , Signal Processing, Computer-Assisted , Electrocardiography/methods , Humans , Algorithms , Signal-To-Noise Ratio
2.
Chem Commun (Camb) ; 59(90): 13498-13501, 2023 Nov 09.
Article En | MEDLINE | ID: mdl-37882367

A unique example of Cu-catalysed synthesis of benzimidazole fused poly-heterocycles via intramolecular C-N coupling reaction has been reported. The method highlights the potential of Cu-catalysed reactions via C-N bond formation in the absence of ligand, oxidant, and additives under inert atmosphere. The mechanistic studies indicate that the reaction is facilitated by the involvement of a benzimidazole N-atom and releases H2 gas, resulting in the synthesis of benzimidazole-fused coupling products in good yield. The versatility of the approach is demonstrated by the synthesis of diverse fused compounds, which exhibit high fluorescence activity and good quantum yield.

3.
J Org Chem ; 88(15): 10701-10710, 2023 Aug 04.
Article En | MEDLINE | ID: mdl-37471271

A short, proficient, and regioselective synthesis of biheterocyclic 5,6-dihydro-quinazolino[4,3-b]quinazolin-8-ones has been revealed via an Fe(0)-powder-mediated, one-pot reductive cyclization protocol. Mechanistic investigation proved that water acts as a source of hydrogen for the reduction of the nitro group and the reaction rate was accelerated by an aldehyde. The designed transformation works under aerobic conditions, providing a series of bio-inspired molecular scaffolds. In addition, the photophysical study showed blue fluorescence emission with a good fluorescence quantum yield.

4.
Sensors (Basel) ; 23(3)2023 Feb 01.
Article En | MEDLINE | ID: mdl-36772600

Industrial Control Systems (ICSs) were initially designed to be operated in an isolated network. However, recently, ICSs have been increasingly connected to the Internet to expand their capability, such as remote management. This interconnectivity of ICSs exposes them to cyber-attacks. At the same time, cyber-attacks in ICS networks are different compared to traditional Information Technology (IT) networks. Cyber attacks on ICSs usually involve a sequence of actions and a multitude of devices. However, current anomaly detection systems only focus on local analysis, which misses the correlation between devices and the progress of attacks over time. As a consequence, they lack an effective way to detect attacks at an entire network scale and predict possible future actions of an attack, which is of significant interest to security analysts to identify the weaknesses of their network and prevent similar attacks in the future. To address these two key issues, this paper presents a system-wide anomaly detection solution using recurrent neural networks combined with correlation analysis techniques. The proposed solution has a two-layer analysis. The first layer targets attack detection, and the second layer analyses the detected attack to predict the next possible attack actions. The main contribution of this paper is the proof of the concept implementation using two real-world ICS datasets, SWaT and Power System Attack. Moreover, we show that the proposed solution effectively detects anomalies and attacks on the scale of the entire ICS network.

5.
Chem Rec ; 22(5): e202100335, 2022 May.
Article En | MEDLINE | ID: mdl-35253973

Over the last twenty years, fluorination on nucleoside has established itself as the most promising tool to use to get biologically active compounds that could sustain the clinical trial by affecting the pharmacodynamics and pharmacokinetic properties. Due to fluorine's inherent unique properties and its judicious introduction into the molecule, makes the corresponding nucleoside metabolically very stable, lipophilic, and opens a new site of intermolecular binding. Fluorination on various nucleosides has been extensively studied as a result, a series of fluorinated nucleosides come up for different therapeutic uses which are either approved by the FDA or under the advanced stage of the clinical trial. Here in this review, we are summarizing the latest development in the chemistry of fluorination on nucleoside that led to varieties of new analogs like carbocyclic, acyclic, and conformationally biased nucleoside and their biological properties, the influence of fluorine on conformation, oligonucleotide stability, and their use in therapeutics.


Fluorine , Nucleosides , Fluorine/chemistry , Molecular Conformation , Nucleosides/chemistry , Nucleosides/pharmacology
6.
Sensors (Basel) ; 22(2)2022 Jan 13.
Article En | MEDLINE | ID: mdl-35062565

Nowadays, there is tremendous growth in the Internet of Things (IoT) applications in our everyday lives. The proliferation of smart devices, sensors technology, and the Internet makes it possible to communicate between the digital and physical world seamlessly for distributed data collection, communication, and processing of several applications dynamically. However, it is a challenging task to monitor and track objects in real-time due to the distinct characteristics of the IoT system, e.g., scalability, mobility, and resource-limited nature of the devices. In this paper, we address the significant issue of IoT object tracking in real time. We propose a system called 'TrackInk' to demonstrate our idea. TrackInk will be capable of pointing toward and taking pictures of visible satellites in the night sky, including but not limited to the International Space Station (ISS) or the moon. Data will be collected from sensors to determine the system's geographical location along with its 3D orientation, allowing for the system to be moved. Additionally, TrackInk will communicate with and send data to ThingSpeak for further cloud-based systems and data analysis. Our proposed system is lightweight, highly scalable, and performs efficiently in a resource-limited environment. We discuss a detailed system's architecture and show the performance results using a real-world hardware-based experimental setup.

7.
J Org Chem ; 86(24): 18067-18080, 2021 12 17.
Article En | MEDLINE | ID: mdl-34813342

A novel, efficient, and atom-economical approach for the construction of quinazolinones from 2-nitrobenzaldehydes has been unveiled via copper-catalyzed nitrile formation, hydrolysis, and reduction in one pot for the first time. In this reaction, urea is used as a source of nitrogen for nitrile formation, hydrazine hydrate is used for both the reduction of the nitro group and the hydrolysis of nitrile, and atmospheric oxygen is used as the sole oxidant. The method portrays a wide substrate scope with good functional group tolerances. Moreover, this method was applied for the synthesis of schizocommunin, tryptanthrin, phaitanthrin-A, phaitanthrin-B, and 8H-quinazolino[4,3-b]quinazolin-8-one.


Biological Products , Copper , Aldehydes , Benzaldehydes , Catalysis , Molecular Structure , Quinazolinones
8.
Sensors (Basel) ; 21(20)2021 Oct 14.
Article En | MEDLINE | ID: mdl-34696053

Internet of Things (IoT) applications and services are becoming more prevalent in our everyday life. However, such an interconnected network of intelligent physical entities needs appropriate security to sensitive information. That said, the need for proper authentication and authorization is paramount. Access control is in the front line of such mechanisms. Access control determines the use of resources only to the specified and authorized users based on appropriate policy enforcement. IoT demands more sophisticated access control in terms of its usability and efficiency in protecting sensitive information. This conveys the need for access control to serve system-specific requirements and be flexibly combined with other access control approaches. In this paper, we discuss the potential for employing protocol-based and hybrid access control for IoT systems and examine how that can overcome the limitations of traditional access control mechanisms. We also focus on the key benefits and constraints of this integration. Our work further enhances the need to build hierarchical access control for large-scale IoT systems (e.g., Industrial IoT (IIoT) settings) with protocol-based and hybrid access control approaches. We, moreover, list the associated open issues to make such approaches efficient for access control in large-scale IoT systems.

9.
Sensors (Basel) ; 21(16)2021 Aug 18.
Article En | MEDLINE | ID: mdl-34451002

With the advancement of human-computer interaction, robotics, and especially humanoid robots, there is an increasing trend for human-to-human communications over online platforms (e.g., zoom). This has become more significant in recent years due to the Covid-19 pandemic situation. The increased use of online platforms for communication signifies the need to build efficient and more interactive human emotion recognition systems. In a human emotion recognition system, the physiological signals of human beings are collected, analyzed, and processed with the help of dedicated learning techniques and algorithms. With the proliferation of emerging technologies, e.g., the Internet of Things (IoT), future Internet, and artificial intelligence, there is a high demand for building scalable, robust, efficient, and trustworthy human recognition systems. In this paper, we present the development and progress in sensors and technologies to detect human emotions. We review the state-of-the-art sensors used for human emotion recognition and different types of activity monitoring. We present the design challenges and provide practical references of such human emotion recognition systems in the real world. Finally, we discuss the current trends in applications and explore the future research directions to address issues, e.g., scalability, security, trust, privacy, transparency, and decentralization.


Artificial Intelligence , COVID-19 , Emotions , Humans , Pandemics , SARS-CoV-2
10.
J Org Chem ; 86(5): 4081-4097, 2021 Mar 05.
Article En | MEDLINE | ID: mdl-33626283

An efficient and atom-economical palladium-catalyzed intramolecular cross dehydrogenative coupling (CDC) reaction has been developed for the construction of highly π-conjugated benzimidazo[1,2-a]quinoline-fused isoxazole scaffolds using molecular oxygen as sole oxidant. The approach portrayed wide substrate scope with good functional group tolerance and depicted a useful tool for the generation of fluorescence active compounds with high quantum yield. Synthetic versatility of the method via Fe-catalyzed reductive isoxazole ring cleavage toward pyridine, pyrimidine, pyrazole fused heteropolycyclic compounds has been showcase.

11.
Sensors (Basel) ; 20(20)2020 Oct 19.
Article En | MEDLINE | ID: mdl-33086542

There has been a tremendous growth in the number of smart devices and their applications (e.g., smart sensors, wearable devices, smart phones, smart cars, etc.) in use in our everyday lives. This is accompanied by a new form of interconnection between the physical and digital worlds, commonly known as the Internet of Things (IoT). This is a paradigm shift, where anything and everything can be interconnected via a communication medium. In such systems, security is a prime concern and protecting the resources (e.g., applications and services) from unauthorized access needs appropriately designed security and privacy solutions. Building secure systems for the IoT can only be achieved through a thorough understanding of the particular needs of such systems. The state of the art is lacking a systematic analysis of the security requirements for the IoT. Motivated by this, in this paper, we present a systematic approach to understand the security requirements for the IoT, which will help designing secure IoT systems for the future. In developing these requirements, we provide different scenarios and outline potential threats and attacks within the IoT. Based on the characteristics of the IoT, we group the possible threats and attacks into five areas, namely communications, device/services, users, mobility and integration of resources. We then examine the existing security requirements for IoT presented in the literature and detail our approach for security requirements for the IoT. We argue that by adhering to the proposed requirements, an IoT system can be designed securely by achieving much of the promised benefits of scalability, usability, connectivity, and flexibility in a practical and comprehensive manner.

12.
Carbohydr Res ; 497: 108113, 2020 Nov.
Article En | MEDLINE | ID: mdl-32858257

Truncated 3'-deoxy- 3', 3' difluororibofuranosyl pyrimidine nucleoside derivatives were synthesized from d-ribose via ß-apioribo pyrimidine nucleoside intermediates 11a-c. The synthetic approach signifies that truncation at C3' position of apioribose ring of 13a-c by oxidative cleavage of diols with Pb(OAc)4 and followed by fluorination with DAST as key steps. Cytotoxic evaluation of synthesized truncated nucleoside derivatives 16a-c and 19a-c were tested against MCF7 and MDA-MB-231 breast cancer cell lines. However, only 19a was shown minimal growth suppression activity on MDA-MB-231 cancer cell lines.


Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Drug Design , Nucleosides/chemical synthesis , Nucleosides/pharmacology , Pyrimidines/chemistry , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Chemistry Techniques, Synthetic , Humans , MCF-7 Cells , Nucleosides/chemistry
13.
Drug Dev Res ; 81(3): 274-282, 2020 05.
Article En | MEDLINE | ID: mdl-31643118

In view of the potent anticancer activity of the d-arabino-configured cytosine nucleoside (ara-C), apioarabinofuranosyl pyrimidine nucleosides were designed and synthesized from d-ribose as starting material. The synthetic strategy signifies that tosylation followed by in situ cyclization, one-pot controlled oxidative cleavage and acetylation by Pb(OAc)4 , stereoselective nucleobase condensation, inversion of hydroxyl group and uracil group converted to cytosine as the key steps. Synthesized apioarabinofuranosyl pyrimidine nucleosides were tested using breast, colon, and ovarian cancer cell lines. However, only compound 19a, 19b, and 22b have a moderate growth-suppressive effect against the luminal A breast cancer cell line MCF7.


Antineoplastic Agents/pharmacology , Cytarabine/pharmacology , Pyrimidines/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Cell Line, Tumor , Colonic Neoplasms/drug therapy , Colonic Neoplasms/pathology , Cytarabine/analogs & derivatives , Cytarabine/chemistry , Female , Humans , MCF-7 Cells , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/pathology , Pyrimidines/chemical synthesis , Pyrimidines/chemistry , Structure-Activity Relationship
14.
Anticancer Agents Med Chem ; 18(10): 1425-1431, 2018.
Article En | MEDLINE | ID: mdl-29577866

BACKGROUND: Modified nucleosides established a prime role as therapeutic drugs. OBJECTIVE: Design and synthesis of novel truncated carbocyclic nucleoside with modified nucleobases and evaluation of their anticancer properties. METHODS: Novel truncated carbocyclic nucleoside analogues were synthesized from a versatile starting material D-ribose. The synthetic route includes stereoselective Grignard reaction, Wittig olefination, ring closing metathesis, double bond hydrogenation and Mitsunobu nucleobase condensation as the key steps. Cytotoxicity was measured using MTT assay in breast cancer cell lines (MCF7 and MDA-MB-231), ovarian cancer cell lines (IGROV1 and OVCAR8). RESULT & CONCLUSION: The synthesized compounds were characterized using spectroscopy techniques. The synthesized compounds induced cytotoxicity in breast cancer cell lines (MCF7 and MDA-MB-231), ovarian cancer cell lines (IGROV1 and OVCAR8) while minimal effect on primary cell line. Among the eight analogues, 1b and 1d showed the highest cytotoxicity effect and induced autophagy mode of cell death. These compounds induced autophagy by inactivating AKT and mTOR pathway. In addition, PARP1 was found to be stabilized upon treatment with compound 1b and 1d and is one of the known markers associated with induction of autophagy through the AMPK/mTOR pathway after DNA damage. Taken together, these results suggest that compounds 1b and 1d inhibit cancer cell proliferation through mTOR inactivation-mediated induction of autophagy.


Antineoplastic Agents/pharmacology , Nucleosides/pharmacology , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , MCF-7 Cells , Molecular Conformation , Nucleosides/analogs & derivatives , Nucleosides/chemistry , Structure-Activity Relationship , Tumor Cells, Cultured
15.
Carbohydr Res ; 416: 24-31, 2015 Oct 30.
Article En | MEDLINE | ID: mdl-26342153

A versatile and stereoselective total synthesis of (+) and (-) pentenomycin I, (+) halopentenomycins I and dehydropentenomycin from a common chiral polyhydroxylated cyclopentene through oxidation and protection/deprotection has been described. Stereoselective hydroxymethylation, stereoselective Grignard reaction and ring closing metathesis are the key features of our approach.


Cyclopentanes/chemical synthesis , Chemistry Techniques, Synthetic , Cyclopentanes/chemistry , Ribose/chemistry , Stereoisomerism
16.
Carbohydr Res ; 398: 13-8, 2014 Oct 29.
Article En | MEDLINE | ID: mdl-25238125

An efficient synthetic route to isoxazoline fused carbocycles from carbohydrate scaffolds that comprise of free hydroxyl group(s) is described with high regio- and stereoselectivity. Montmorillonite K-10/chloramine T oxidation and in situ intramolecular nitrile oxide-alkene cycloaddition (INOC) of D-ribose derived oximes have been developed for the diversity oriented synthesis of isoxazoline fused five and six membered carbocycles.


Alkenes/chemistry , Aluminum Silicates/chemistry , Cycloaddition Reaction , Isoxazoles/chemistry , Nitriles/chemistry , Oxides/chemistry , Ribose/chemical synthesis , Clay , Hydrogen-Ion Concentration , Ribose/chemistry , Stereoisomerism , Substrate Specificity
17.
Bioorg Med Chem ; 17(10): 3733-8, 2009 May 15.
Article En | MEDLINE | ID: mdl-19375920

On the basis of potent and selective binding affinity of truncated 4'-thioadenosine derivatives at the human A(3) adenosine receptor (AR), their bioisosteric 4'-oxo derivatives were designed and synthesized from commercially available 2,3-O-isopropylidene-D-erythrono lactone. The derivatives tested in AR binding assays were substituted at the C2 and N(6) positions. All synthesized nucleosides exhibited potent and selective binding affinity at the human A(3) AR. They were less potent than the corresponding 4'-thio analogues, but showed still selective to other subtypes. The 2-Cl series generally were better than the 2-H series in view of binding affinity and selectivity. Among compounds tested, compound 5d (X=Cl, R=3-bromobenzyl) showed the highest binding affinity (K(i)=13.0+/-6.9 nM) at the hA(3) AR with high selectivity (at least 88-fold) in comparison to other AR subtypes. Like the corresponding truncated 4'-thio series, compound 5d antagonized the action of an agonist to inhibit forskolin-stimulated adenylate cyclase in hA(3) AR-expressing CHO cells. Although the 4'-oxo series were less potent than the 4'-thio series, this class of human A(3) AR antagonists is also regarded as another good template for the design of A(3) AR antagonists and for further drug development.


Adenosine A3 Receptor Antagonists , Adenosine/analogs & derivatives , Furans/chemistry , Purines/chemistry , Thionucleosides/chemistry , Adenosine/chemical synthesis , Adenosine/chemistry , Adenosine/pharmacology , Adenosine A1 Receptor Antagonists , Adenosine A2 Receptor Antagonists , Adenylyl Cyclases/chemistry , Adenylyl Cyclases/metabolism , Adenylyl Cyclases/pharmacology , Animals , CHO Cells , Cell Line , Colforsin/chemistry , Colforsin/pharmacology , Cricetinae , Cricetulus , Furans/chemical synthesis , Furans/pharmacology , Humans , Purines/chemical synthesis , Purines/pharmacology , Receptor, Adenosine A1/metabolism , Receptor, Adenosine A3/metabolism , Receptors, Adenosine A2/metabolism , Structure-Activity Relationship , Thionucleosides/chemical synthesis , Thionucleosides/pharmacology
18.
J Med Chem ; 51(20): 6609-13, 2008 Oct 23.
Article En | MEDLINE | ID: mdl-18811138

Novel D- and l-4'-thioadenosine derivatives lacking the 4'-hydroxymethyl moiety were synthesized, starting from d-mannose and d-gulonic gamma-lactone, respectively, as potent and selective species-independent A 3 adenosine receptor (AR) antagonists. Among the novel 4'-truncated 2-H nucleosides tested, a N(6)-(3-chlorobenzyl) derivative 7c was the most potent at the human A 3 AR (K i = 1.5 nM), but a N(6)-(3-bromobenzyl) derivative 7d showed the optimal species-independent binding affinity.


Adenosine A3 Receptor Antagonists , Adenosine/analogs & derivatives , Thionucleosides/chemical synthesis , Thionucleosides/pharmacology , Adenosine/chemical synthesis , Adenosine/chemistry , Adenosine/pharmacology , Animals , Humans , Molecular Structure , Rats , Receptor, Adenosine A3/metabolism , Structure-Activity Relationship , Thionucleosides/chemistry
19.
Nucleic Acids Symp Ser (Oxf) ; (52): 641-2, 2008.
Article En | MEDLINE | ID: mdl-18776543

We have established structure-activity relationships of novel truncated D-4'-thioadenosine derivatives from D-mannose as potent and selective A(3) adenosine receptor (AR) antagonists. At the human A(3) AR, most of N(6)-substituted analogues showed high potency and selectivity and acted as pure antagonists in a cyclic AMP functional assay. Among compounds tested, 2-chloro-N(6)-3-chlorobenzyl and N(6)-3-chlorobenzyl analogues displayed very high binding affinities (K(i) = 1.66 nM and 1.5 nM, respectively) at the human A(3) AR. Truncated 4'-thioadenosine derivatives studied here are regarded as an excellent template for the design of novel A(3) AR antagonists to act at both human and murine species.


Adenosine A3 Receptor Antagonists , Adenosine/analogs & derivatives , Thionucleosides/chemistry , Adenosine/chemistry , Animals , Cell Line , Cricetinae , Drug Design , Humans , Receptor, Adenosine A3/metabolism , Structure-Activity Relationship , Thionucleosides/chemical synthesis , Thionucleosides/metabolism
20.
J Org Chem ; 73(11): 4259-62, 2008 Jun 06.
Article En | MEDLINE | ID: mdl-18454552

Stereoselective synthesis of novel 2',3'-didehydro-2',3'-dideoxy-4'-selenonucleosides (4'-seleno-d4Ns) 4a- c was accomplished via 4'-selenoribofuranosyl pyrimidines 11a- c, as key intermediates. 4'-Selenoribofuranosyl pyrimidines 11a- c were efficiently synthesized from d-ribose or d-gulonic gamma-lactone using a Pummerer-type condensation as a key step. Introduction of 2',3'-double bond was achieved by treating cyclic 2',3'-thiocarbonate with 1,3-dimethyl-2-phenyl-1,3,2-diazaphospholidine.


Dideoxynucleosides/chemistry , Selenium/chemistry , Crystallography, X-Ray , Magnetic Resonance Spectroscopy , Nucleic Acid Conformation , Spectrometry, Mass, Fast Atom Bombardment , Stereoisomerism
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