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1.
Sensors (Basel) ; 24(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38475138

RESUMO

The approach of using more than one processor to compute in order to overcome the complexity of different medical imaging methods that make up an overall job is known as GPU (graphic processing unit)-based parallel processing. It is extremely important for several medical imaging techniques such as image classification, object detection, image segmentation, registration, and content-based image retrieval, since the GPU-based parallel processing approach allows for time-efficient computation by a software, allowing multiple computations to be completed at once. On the other hand, a non-invasive imaging technology that may depict the shape of an anatomy and the biological advancements of the human body is known as magnetic resonance imaging (MRI). Implementing GPU-based parallel processing approaches in brain MRI analysis with medical imaging techniques might be helpful in achieving immediate and timely image capture. Therefore, this extended review (the extension of the IWBBIO2023 conference paper) offers a thorough overview of the literature with an emphasis on the expanding use of GPU-based parallel processing methods for the medical analysis of brain MRIs with the imaging techniques mentioned above, given the need for quicker computation to acquire early and real-time feedback in medicine. Between 2019 and 2023, we examined the articles in the literature matrix that include the tasks, techniques, MRI sequences, and processing results. As a result, the methods discussed in this review demonstrate the advancements achieved until now in minimizing computing runtime as well as the obstacles and problems still to be solved in the future.


Assuntos
Algoritmos , Gráficos por Computador , Humanos , Software , Encéfalo , Imageamento por Ressonância Magnética/métodos , Processamento de Imagem Assistida por Computador/métodos
2.
Patient Prefer Adherence ; 17: 3015-3031, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38027077

RESUMO

Background: Maintaining mobility is fundamental to active aging, allowing older adults to lead dynamic and independent lives. The perception of mobility among older adults significantly impacts their overall well-being and quality of life. Given the aging population, mobility has become an increasingly pressing issue. Aim: This study focused on the perception of urban neighborhoods, including considerations of urban tissue (crossings and sidewalk maintenance), urban scenes (benches and traffic), and safety (fears and street lighting quality). We investigated the differences in the perception of the surroundings of residences by urban and rural seniors concerning their demographic and social characteristics and environmental determinants. Methods: A quantitative study design utilizing a questionnaire survey was employed. Data were collected mainly through face-to-face interviews in the field (PAPI) and via an online questionnaire (CAWI). The final sample comprised 525 participants. Hypotheses regarding the influence of gender, age, social status, level of physical activity, degree of urbanization, and region on environmental perception were tested using ordinal regression. Results: The hypothesis regarding the dependence of the perception of the surroundings on the level of urbanization was confirmed; that regarding the dependence of the perception of the residence surroundings on seniors' age was not confirmed. The other hypotheses were partially confirmed. For the seven investigated environmental attributes, gender was significant in two cases, social status and physical activity in three cases, and region in four cases. Conclusion: While most studies have focused on urban settings, this study highlights the situation in rural municipalities. Substantially worse pedestrian conditions in availability of pedestrian crossings, benches, and lighting were recognized in rural municipalities versus cities. Understanding the complexity of mobility and the spatial locations relevant for older persons concerning potential barriers and facilitators for mobility aids in planning and adapting neighborhood environments to promote active and healthy aging in place.

3.
IEEE Trans Med Imaging ; 42(12): 3987-4000, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37768798

RESUMO

Polyps are very common abnormalities in human gastrointestinal regions. Their early diagnosis may help in reducing the risk of colorectal cancer. Vision-based computer-aided diagnostic systems automatically identify polyp regions to assist surgeons in their removal. Due to their varying shape, color, size, texture, and unclear boundaries, polyp segmentation in images is a challenging problem. Existing deep learning segmentation models mostly rely on convolutional neural networks that have certain limitations in learning the diversity in visual patterns at different spatial locations. Further, they fail to capture inter-feature dependencies. Vision transformer models have also been deployed for polyp segmentation due to their powerful global feature extraction capabilities. But they too are supplemented by convolution layers for learning contextual local information. In the present paper, a polyp segmentation model CoInNet is proposed with a novel feature extraction mechanism that leverages the strengths of convolution and involution operations and learns to highlight polyp regions in images by considering the relationship between different feature maps through a statistical feature attention unit. To further aid the network in learning polyp boundaries, an anomaly boundary approximation module is introduced that uses recursively fed feature fusion to refine segmentation results. It is indeed remarkable that even tiny-sized polyps with only 0.01% of an image area can be precisely segmented by CoInNet. It is crucial for clinical applications, as small polyps can be easily overlooked even in the manual examination due to the voluminous size of wireless capsule endoscopy videos. CoInNet outperforms thirteen state-of-the-art methods on five benchmark polyp segmentation datasets.


Assuntos
Endoscopia por Cápsula , Cirurgiões , Humanos , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador
4.
BMC Geriatr ; 23(1): 447, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37474928

RESUMO

BACKGROUND: Attention is focused on the health and physical fitness of older adults due to their increasing age. Maintaining physical abilities, including safe walking and movement, significantly contributes to the perception of health in old age. One of the early signs of declining fitness in older adults is limited mobility. Approximately one third of 70-year-olds and most 80-year-olds report restrictions on mobility in their apartments and immediate surroundings. Restriction or loss of mobility is a complex multifactorial process, which makes older adults prone to falls, injuries, and hospitalizations and worsens their quality of life while increasing overall mortality. OBJECTIVE: The objective of the study is to identify the factors that have had a significant impact on mobility in recent years and currently, and to identify gaps in our understanding of these factors. The study aims to highlight areas where further research is needed and where new and effective solutions are required. METHODS: The PRISMA methodology was used to conduct a scoping review in the Scopus and Web of Science databases. Papers published from 2007 to 2021 were searched in November 2021. Of these, 52 papers were selected from the initial 788 outputs for the final analysis. RESULTS: The final selected papers were analyzed, and the key determinants were found to be environmental, physical, cognitive, and psychosocial, which confirms the findings of previous studies. One new determinant is technological. New and effective solutions lie in understanding the interactions between different determinants of mobility, addressing environmental factors, and exploring opportunities in the context of emerging technologies, such as the integration of smart home technologies, design of accessible and age-friendly public spaces, development of policies and regulations, and exploration of innovative financing models to support the integration of assistive technologies into the lives of seniors. CONCLUSION: For an effective and comprehensive solution to support senior mobility, the determinants cannot be solved separately. Physical, cognitive, psychosocial, and technological determinants can often be perceived as the cause/motivation for mobility. Further research on these determinants can help to arrive at solutions for environmental determinants, which, in turn, will help improve mobility. Future studies should investigate financial aspects, especially since many technological solutions are expensive and not commonly available, which limits their use.


Assuntos
Qualidade de Vida , Caminhada , Idoso , Humanos , Bases de Dados Factuais , Exercício Físico , Aptidão Física
5.
Sensors (Basel) ; 23(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37112218

RESUMO

Due to the complex underwater environment, conventional measurement and sensing methods used for land are difficult to apply directly in the underwater environment. Especially for seabed topography, it is impossible to perform long-distance and accurate detection by electromagnetic waves. Therefore, various types of acoustic and even optical sensing devices for underwater applications have been used. Equipped with submersibles, these underwater sensors can detect a wide underwater range accurately. In addition, the development of sensor technology will be modified and optimized according to the needs of ocean exploitation. In this paper, we propose a multiagent approach for optimizing the quality of monitoring (QoM) in underwater sensor networks. Our framework aspires to optimize the QoM by resorting to the machine learning concept of diversity. We devise a multiagent optimization procedure which is able to both reduce the redundancy among the sensor readings and maximize the diversity in a distributed and adaptive manner. The mobile sensor positions are adjusted iteratively using a gradient type of updates. The overall framework is tested through simulations based on realistic environment conditions. The proposed approach is compared to other placement approaches and is found to achieve a higher QoM with a smaller number of sensors.

6.
Math Biosci Eng ; 20(2): 2908-2919, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36899564

RESUMO

Investigating the effect of changes in neuronal connectivity on the brain's behavior is of interest in neuroscience studies. Complex network theory is one of the most capable tools to study the effects of these changes on collective brain behavior. By using complex networks, the neural structure, function, and dynamics can be analyzed. In this context, various frameworks can be used to mimic neural networks, among which multi-layer networks are a proper one. Compared to single-layer models, multi-layer networks can provide a more realistic model of the brain due to their high complexity and dimensionality. This paper examines the effect of changes in asymmetry coupling on the behaviors of a multi-layer neuronal network. To this aim, a two-layer network is considered as a minimum model of left and right cerebral hemispheres communicated with the corpus callosum. The chaotic model of Hindmarsh-Rose is taken as the dynamics of the nodes. Only two neurons of each layer connect two layers of the network. In this model, it is assumed that the layers have different coupling strengths, so the effect of each coupling change on network behavior can be analyzed. As a result, the projection of the nodes is plotted for several coupling strengths to investigate how the asymmetry coupling influences the network behaviors. It is observed that although no coexisting attractor is present in the Hindmarsh-Rose model, an asymmetry in couplings causes the emergence of different attractors. The bifurcation diagrams of one node of each layer are presented to show the variation of the dynamics due to coupling changes. For further analysis, the network synchronization is investigated by computing intra-layer and inter-layer errors. Calculating these errors shows that the network can be synchronized only for large enough symmetric coupling.


Assuntos
Encéfalo , Neurônios , Neurônios/fisiologia , Encéfalo/fisiologia , Redes Neurais de Computação , Análise por Conglomerados , Modelos Neurológicos
7.
Genes (Basel) ; 14(2)2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36833377

RESUMO

Infertility has recently emerged as a severe medical problem. The essential elements in male infertility are sperm morphology, sperm motility, and sperm density. In order to analyze sperm motility, density, and morphology, laboratory experts do a semen analysis. However, it is simple to err when using a subjective interpretation based on laboratory observation. In this work, a computer-aided sperm count estimation approach is suggested to lessen the impact of experts in semen analysis. Object detection techniques concentrating on sperm motility estimate the number of active sperm in the semen. This study provides an overview of other techniques that we can compare. The Visem dataset from the Association for Computing Machinery was used to test the proposed strategy. We created a labelled dataset to prove that our network can detect sperms in images. The best not-super tuned result is mAP 72.15.


Assuntos
Infertilidade Masculina , Sêmen , Humanos , Masculino , Infertilidade Masculina/diagnóstico , Análise do Sêmen , Motilidade dos Espermatozoides , Espermatozoides
8.
Sensors (Basel) ; 23(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36772267

RESUMO

The deployment of optical network infrastructure and development of new network services are growing rapidly for beyond 5/6G networks. However, optical networks are vulnerable to several types of security threats, such as single-point failure, wormhole attacks, and Sybil attacks. Since the uptake of e-commerce and e-services has seen an unprecedented surge in recent years, especially during the COVID-19 pandemic, the security of these transactions is essential. Blockchain is one of the most promising solutions because of its decentralized and distributed ledger technology, and has been employed to protect these transactions against such attacks. However, the security of blockchain relies on the computational complexity of certain mathematical functions, and because of the evolution of quantum computers, its security may be breached in real-time in the near future. Therefore, researchers are focusing on combining quantum key distribution (QKD) with blockchain to enhance blockchain network security. This new technology is known as quantum-secured blockchain. This article describes different attacks in optical networks and provides a solution to protect networks against security attacks by employing quantum-secured blockchain in optical networks. It provides a brief overview of blockchain technology with its security loopholes, and focuses on QKD, which makes blockchain technology more robust against quantum attacks. Next, the article provides a broad view of quantum-secured blockchain technology. It presents the network architecture for the future research and development of secure and trusted optical networks using quantum-secured blockchain. The article also highlights some research challenges and opportunities.

9.
Technol Health Care ; 31(1): 205-215, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35848002

RESUMO

BACKGROND: One of the important areas of heart research is to analyze heart rate variability during (HRV) walking. OBJECTIVE: In this research, we investigated the correction between heart activation and the variations of walking paths. METHOD: We employed Shannon entropy to analyze how the information content of walking paths affects the information content of HRV. Eight healthy students walked on three designed walking paths with different information contents while we recorded their ECG signals. We computed and analyzed the Shannon entropy of the R-R interval time series (as an indicator of HRV) versus the Shannon entropy of different walking paths and accordingly evaluated their relation. RESULTS: According to the obtained results, walking on the path that contains more information leads to less information in the R-R time series. CONCLUSION: The analysis method employed in this research can be extended to analyze the relation between other physiological signals (such as brain or muscle reactions) and the walking path.


Assuntos
Eletrocardiografia , Caminhada , Humanos , Frequência Cardíaca/fisiologia , Entropia , Fatores de Tempo
10.
PLoS One ; 17(10): e0274596, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36201526

RESUMO

A social network is one of the efficient tools for information propagation. The content is the bridge between the product and its customers. Evaluating the user's content creation is a valuable feature to improve information spreading on the social network. This paper proposes a method for extracting brand value with influencers by combining the user's amplification and content creation in influencer marketing. The amplification factors are studied based on the propagation of the posts on the social network in a duration time. Those factors are more valuable than before when using influencer marketing at a determined time. Moreover, the content creation score is also studied to measure content creation based on the passion point with a brand and its quality. The amplification factors and content creation score are combined to analyze posts' interest in detecting the emerging influent users for a product in the influencer marketing campaign. Using the amplification factors, the passion points, and the content creation score, a system to manage the influencer marketing on Facebook has been constructed and tested in the real-world campaign. The experimental results show that the proposed method's influencers bring the conversion rate's efficiency and revenue in the influencer marketing campaign.


Assuntos
Mídias Sociais , Humanos , Marketing/métodos , Projetos de Pesquisa , Rede Social
11.
Appl Soft Comput ; 125: 109109, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35693544

RESUMO

The COVID-19 pandemic has posed an unprecedented threat to the global public health system, primarily infecting the airway epithelial cells in the respiratory tract. Chest X-ray (CXR) is widely available, faster, and less expensive therefore it is preferred to monitor the lungs for COVID-19 diagnosis over other techniques such as molecular test, antigen test, antibody test, and chest computed tomography (CT). As the pandemic continues to reveal the limitations of our current ecosystems, researchers are coming together to share their knowledge and experience in order to develop new systems to tackle it. In this work, an end-to-end IoT infrastructure is designed and built to diagnose patients remotely in the case of a pandemic, limiting COVID-19 dissemination while also improving measurement science. The proposed framework comprises six steps. In the last step, a model is designed to interpret CXR images and intelligently measure the severity of COVID-19 lung infections using a novel deep neural network (DNN). The proposed DNN employs multi-scale sampling filters to extract reliable and noise-invariant features from a variety of image patches. Experiments are conducted on five publicly available databases, including COVIDx, COVID-19 Radiography, COVID-XRay-5K, COVID-19-CXR, and COVIDchestxray, with classification accuracies of 96.01%, 99.62%, 99.22%, 98.83%, and 100%, and testing times of 0.541, 0.692, 1.28, 0.461, and 0.202 s, respectively. The obtained results show that the proposed model surpasses fourteen baseline techniques. As a result, the newly developed model could be utilized to evaluate treatment efficacy, particularly in remote locations.

12.
Comput Biol Med ; 145: 105420, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35390744

RESUMO

Depression is a major depressive disorder characterized by persistent sadness and a sense of worthlessness, as well as a loss of interest in pleasurable activities, which leads to a variety of physical and emotional problems. It is a worldwide illness that affects millions of people and should be detected at an early stage to prevent negative effects on an individual's life. Electroencephalogram (EEG) is a non-invasive technique for detecting depression that analyses brain signals to determine the current mental state of depressed subjects. In this study, we propose a method for automatic feature extraction to detect depression by first constructing a graph from the dataset where the nodes represent the subjects in the dataset and where the edge weights obtained using the Euclidean distance reflect the relationship between them. The Node2vec algorithmic framework is then used to compute feature representations for nodes in a graph in the form of node embeddings ensuring that similar nodes in the graph remain near in the embedding. These node embeddings act as useful features which can be directly used by classification algorithms to determine whether a subject is depressed thus reducing the effort required for manual handcrafted feature extraction. To combine the features collected from the multiple channels of the EEG data, the method proposes three types of fusion methods: graph-level fusion, feature-level fusion, and decision-level fusion. The proposed method is tested on three publicly available datasets with 3, 20, and 128 channels, respectively, and compared to five state-of-the-art methods. The results show that the proposed method detects depression effectively with a peak accuracy of 0.933 in decision-level fusion, which is the highest among the state-of-the-art methods.


Assuntos
Interfaces Cérebro-Computador , Transtorno Depressivo Maior , Algoritmos , Depressão/diagnóstico , Transtorno Depressivo Maior/diagnóstico , Eletroencefalografia , Humanos
13.
Appl Microbiol Biotechnol ; 106(8): 2827-2853, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35384450

RESUMO

The need for biosensors has evolved in the detection of molecules, diseases, and pollution from various sources. This requirement has headed to the development of accurate and powerful equipment for analysis using biological sensing component as a biosensor. Biosensors have the advantage of rapid detection that can beat the conventional methods for the detection of the same molecules. Bio-chemiluminescence-based sensors are very sensitive during use in biological immune assay systems. Optical biosensors are emerging with time as they have the advantage that they act with a change in the refractive index. Carbon nanotube-based sensors are another area that has an important role in the biosensor field. Bioluminescence gives much higher quantum yields than classical chemiluminescence. Electro-generated bioluminescence has the advantage of miniature size and can produce a high signal-to-noise ratio and the controlled emission. Recent advances in biological techniques and instrumentation involving fluorescence tag to nanomaterials have increased the sensitivity limit of biosensors. Integrated approaches provided a better perspective for developing specific and sensitive biosensors with high regenerative potentials. This paper mainly focuses on sensors that are important for the detection of multiple molecules related to clinical and environmental applications. KEY POINTS: • The review focusses on the applications of luminescence-based, surface plasmon resonance-based, carbon nanotube-based, and graphene-based biosensors • Potential clinical, environmental, agricultural, and food industry applications/uses of biosensors have been critically reviewed • The current limitations in this field are discussed, as well as the prospects for future advancement.


Assuntos
Técnicas Biossensoriais , Grafite , Nanotubos de Carbono , Luminescência , Ressonância de Plasmônio de Superfície
14.
Biomedicines ; 10(4)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35453637

RESUMO

This work analyses the results of research regarding the predisposition of genetic hematological risks associated with secondary polyglobulia. The subjects of the study were selected based on shared laboratory markers and basic clinical symptoms. JAK2 (Janus Kinase 2) mutation negativity represented the common genetic marker of the subjects in the sample of interest. A negative JAK2 mutation hypothetically excluded the presence of an autonomous myeloproliferative disease at the time of detection. The parameters studied in this work focused mainly on thrombotic, immunological, metabolic, and cardiovascular risks. The final goal of the work was to discover the most significant key markers for the diagnosis of high-risk patients and to exclude the less important or only complementary markers, which often represent a superfluous economic burden for healthcare institutions. These research results are applicable as a clinical guideline for the effective diagnosis of selected parameters that demonstrated high sensitivity and specificity. According to the results obtained in the present research, groups with a high incidence of mutations were evaluated as being at higher risk for polycythemia vera disease. It was not possible to clearly determine which of the patients examined had a higher risk of developing the disease as different combinations of mutations could manifest different symptoms of the disease. In general, the entire study group was at risk for manifestations of polycythemia vera disease without a clear diagnosis. The group with less than 20% incidence appeared to be clinically insignificant for polycythemia vera testing and thus there is a potential for saving money in mutation testing. On the other hand, the JAK V617F (somatic mutation of JAK2) parameter from this group should be investigated as it is a clear exclusion or confirmation of polycythemia vera as the primary disease.

15.
Technol Health Care ; 30(4): 859-868, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34842201

RESUMO

BACKGROUND: Analysis of the reactions of different organs to external stimuli is an important area of research in physiological science. OBJECTIVE: In this paper, we investigated the correlation between the brain and facial muscle activities by information-based analysis of electroencephalogram (EEG) signals and electromyogram (EMG) signals using Shannon entropy. METHOD: The EEG and EMG signals of thirteen subjects were recorded during rest and auditory stimulations using relaxing, pop, and rock music. Accordingly, we calculated the Shannon entropy of these signals. RESULTS: The results showed that rock music has a greater effect on the information of EEG and EMG signals than pop music, which itself has a greater effect than relaxing music. Furthermore, a strong correlation (r= 0.9980) was found between the variations of the information of EEG and EMG signals. CONCLUSION: The activities of the facial muscle and brain are correlated in different conditions. This technique can be utilized to investigate the correlation between the activities of different organs versus brain activity in different situations.


Assuntos
Eletroencefalografia , Músculos Faciais , Estimulação Acústica , Encéfalo/fisiologia , Eletroencefalografia/métodos , Eletromiografia/métodos , Músculos Faciais/fisiologia , Humanos
16.
Sensors (Basel) ; 21(23)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34883826

RESUMO

Selective, sensitive and affordable techniques to detect disease and underlying health issues have been developed recently. Biosensors as nanoanalytical tools have taken a front seat in this context. Nanotechnology-enabled progress in the health sector has aided in disease and pandemic management at a very early stage efficiently. This report reflects the state-of-the-art of nanobiosensor-based virus detection technology in terms of their detection methods, targets, limits of detection, range, sensitivity, assay time, etc. The article effectively summarizes the challenges with traditional technologies and newly emerging biosensors, including the nanotechnology-based detection kit for COVID-19; optically enhanced technology; and electrochemical, smart and wearable enabled nanobiosensors. The less explored but crucial piezoelectric nanobiosensor and the reverse transcription-loop mediated isothermal amplification (RT-LAMP)-based biosensor are also discussed here. The article could be of significance to researchers and doctors dedicated to developing potent, versatile biosensors for the rapid identification of COVID-19. This kind of report is needed for selecting suitable treatments and to avert epidemics.


Assuntos
Técnicas Biossensoriais , COVID-19 , Humanos , Nanotecnologia , Técnicas de Amplificação de Ácido Nucleico , Pandemias , SARS-CoV-2 , Sensibilidade e Especificidade
17.
Sensors (Basel) ; 21(24)2021 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-34960384

RESUMO

Cyber-attack detection via on-gadget embedded models and cloud systems are widely used for the Internet of Medical Things (IoMT). The former has a limited computation ability, whereas the latter has a long detection time. Fog-based attack detection is alternatively used to overcome these problems. However, the current fog-based systems cannot handle the ever-increasing IoMT's big data. Moreover, they are not lightweight and are designed for network attack detection only. In this work, a hybrid (for host and network) lightweight system is proposed for early attack detection in the IoMT fog. In an adaptive online setting, six different incremental classifiers were implemented, namely a novel Weighted Hoeffding Tree Ensemble (WHTE), Incremental K-Nearest Neighbors (IKNN), Incremental Naïve Bayes (INB), Hoeffding Tree Majority Class (HTMC), Hoeffding Tree Naïve Bayes (HTNB), and Hoeffding Tree Naïve Bayes Adaptive (HTNBA). The system was benchmarked with seven heterogeneous sensors and a NetFlow data infected with nine types of recent attack. The results showed that the proposed system worked well on the lightweight fog devices with ~100% accuracy, a low detection time, and a low memory usage of less than 6 MiB. The single-criteria comparative analysis showed that the WHTE ensemble was more accurate and was less sensitive to the concept drift.


Assuntos
Internet das Coisas , Teorema de Bayes , Big Data , Diagnóstico Precoce
18.
Oxid Med Cell Longev ; 2021: 3155962, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34737844

RESUMO

Nanotechnology is gaining significant attention, with numerous biomedical applications. Silver in wound dressings, copper oxide and silver in antibacterial preparations, and zinc oxide nanoparticles as a food and cosmetic ingredient are common examples. However, adverse effects of nanoparticles in humans and the environment from extended exposure at varied concentrations have yet to be established. One of the drawbacks of employing nanoparticles is their tendency to cause oxidative stress, a significant public health concern with life-threatening consequences. Cardiovascular, renal, and respiratory problems and diabetes are among the oxidative stress-related disorders. In this context, phytoantioxidant functionalized nanoparticles could be a novel and effective alternative. In addition to performing their intended function, they can protect against oxidative damage. This review was designed by searching through various websites, books, and articles found in PubMed, Science Direct, and Google Scholar. To begin with, oxidative stress, its related diseases, and the mechanistic basis of oxidative damage caused by nanoparticles are discussed. One of the main mechanisms of action of nanoparticles was unearthed to be oxidative stress, which limits their use in humans. Secondly, the role of phytoantioxidant functionalized nanoparticles in oxidative damage prevention is critically discussed. The parameters for the characterization of nanoparticles were also discussed. The majority of silver, gold, iron, zinc oxide, and copper nanoparticles produced utilizing various plant extracts were active free radical scavengers. This potential is linked to several surface fabricated phytoconstituents, such as flavonoids and phenols. These phytoantioxidant functionalized nanoparticles could be a better alternative to nanoparticles prepared by other existing approaches.


Assuntos
Antioxidantes/farmacologia , Sequestradores de Radicais Livres/farmacologia , Nanopartículas Metálicas/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Animais , Antioxidantes/química , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Compostos Fitoquímicos/química
19.
Plants (Basel) ; 10(11)2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34834733

RESUMO

The developments of green-based metallic nanoparticles (gold) are gaining tremendous interest, having potential applications in health care and diagnosis. Therefore, in the present study, Polianthes tuberosa flower filtered extract was used as a reducing and stabilizing agent to synthesize gold nanoparticles (PtubAuNPs). The PtubAuNPs were extensively characterized by UV-visible spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, and X-ray diffraction. The antibacterial activity of PtubAuNPs was determined by the agar well diffusion method; the PtubAuNPs performed extreme antagonistic activity against the tested pathogens. Furthermore, the cytotoxicity of the PtubAuNPs was evaluated in MCF 7 cells by MTT assay. The PtubAuNPs induced toxicity in MCF 7 cells with the least concentration of 100 µg/mL in a dose-dependent method by inducing apoptosis. Overall, the study manifested that PtubAuNPs are a potent nanomaterial that can be employed as an antimicrobial and anticancer agent.

20.
Sensors (Basel) ; 21(17)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34502784

RESUMO

The recent development in wireless networks and devices leads to novel services that will utilize wireless communication on a new level [...].


Assuntos
Tecnologia , Tecnologia sem Fio , Comunicação
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