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1.
Sensors (Basel) ; 24(9)2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38733033

RESUMO

A distributed state observer is designed for state estimation and tracking of mobile robots amidst dynamic environments and occlusions within distributed LiDAR sensor networks. The proposed novel framework enhances three-dimensional bounding box detection and tracking utilizing a consensus-based information filter and a region of interest for state estimation of mobile robots. The framework enables the identification of the input to the dynamic process using remote sensing, enhancing the state prediction accuracy for low-visibility and occlusion scenarios in dynamic scenes. Experimental evaluations in indoor settings confirm the effectiveness of the framework in terms of accuracy and computational efficiency. These results highlight the benefit of integrating stationary LiDAR sensors' state estimates into a switching consensus information filter to enhance the reliability of tracking and to reduce estimation error in the sense of mean square and covariance.

2.
Front Robot AI ; 11: 1212070, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510560

RESUMO

This survey reviews advances in 3D object detection approaches for autonomous driving. A brief introduction to 2D object detection is first discussed and drawbacks of the existing methodologies are identified for highly dynamic environments. Subsequently, this paper reviews the state-of-the-art 3D object detection techniques that utilizes monocular and stereo vision for reliable detection in urban settings. Based on depth inference basis, learning schemes, and internal representation, this work presents a method taxonomy of three classes: model-based and geometrically constrained approaches, end-to-end learning methodologies, and hybrid methods. There is highlighted segment for current trend of multi-view detectors as end-to-end methods due to their boosted robustness. Detectors from the last two kinds were specially selected to exploit the autonomous driving context in terms of geometry, scene content and instances distribution. To prove the effectiveness of each method, 3D object detection datasets for autonomous vehicles are described with their unique features, e. g., varying weather conditions, multi-modality, multi camera perspective and their respective metrics associated to different difficulty categories. In addition, we included multi-modal visual datasets, i. e., V2X that may tackle the problems of single-view occlusion. Finally, the current research trends in object detection are summarized, followed by a discussion on possible scope for future research in this domain.

3.
Accid Anal Prev ; 193: 107225, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37742439

RESUMO

A driving-safety-zone-model-oriented motion planning framework (DSZMF) is proposed for autonomous platoons in heterogeneous driving environments with complex driving behaviors and interactions between human-driven and autonomous vehicles. As an extension of the responsibility-sensitive-safety (RSS) model, the driving safety zone model ensures that autonomous truck platoons adhere to explicit and implicit traffic rules as rational traffic participants. It consists of three zones created by safe distances and artificial potential field (APF), namely the restricted zone, the coordinated zone, and pre-cautionary zone. The Rational Traffic Participant (RTP) module is created by using a Finite State Machine (FSM) to provide an optimized platooning behavioral strategy based on the dynamic states of surrounding vehicles. Furthermore, the distributed model predictive controllers are utilized for motion planning, while the H infinity controller is developed to maintain the string stability of the autonomous platoon. The proposed DSZMF generates behavioral decisions by thoroughly considering the driving safety zone model, string stability, and multiple vehicle dynamics constraints. Finally, three critical scenarios are co-simulated for case studies, and the simulation results demonstrate that the DSZMF improves the safe time integration rate over the existing MCF by 18.9%, 11.1%, and 11.6% in three scenarios, respectively. In addition, DSZMF increases the minimum longitudinal and lateral Time to Collision (TTC) values to reduce collision risks. The case studies validate the efficacy of the proposed method for safety assurance and collaborative control of the autonomous platoon.

4.
Minerva Dent Oral Sci ; 72(5): 239-246, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37255306

RESUMO

BACKGROUND: Tobacco is a major risk factor in oral diseases. Considering the important role of expression miRNA molecules in different diseases, the present study aimed to compare the expression of salivary miRNA-6734, miRNA-3123 and miRNA-4483 in smoker and non-smoker peoples. METHODS: In this case-control study, salivary samples were obtained from 30 smoker's patients and 27 healthy nonsmokers and matched in term of age and sex. RNA was extracted in salivary samples and gene expression was evaluated in all samples. Statistical analysis of data was performed using T and chi-square tests by SPSS (Ver. 16) software at a significant level of less than 0.05. RESULTS: The results of this study showed that the expression level of miRNA-3123 and miRNA-4483 in smokers group was 2.8 and 3.2, respectively, which was increased compared to non-smokers with expression level of 1 (P<0.01). There was a significant decrease in the expression rate of miRNA-6734 in smokers (0.6%) compared to non-smokers (P<0.05). CONCLUSIONS: Based on the results of this study, considering the increasing miRNA-4483 and miRNA-3123 level, as well as the reducing miRNA-6734 level in smokers compared to non-smokers, it seems that evaluation of these two miRNAs as indicator for diagnosis and determination of prognosis of oral diseases associated with smoking can be used.

5.
Front Bioeng Biotechnol ; 10: 1019821, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36406206

RESUMO

The main goals of medicine consist of early detection and effective treatment of different diseases. In this regard, the rise of exosomes as carriers of natural biomarkers has recently attracted a lot of attention and managed to shed more light on the future of early disease diagnosis methods. Here, exosome biogenesis, its role as a biomarker in metabolic disorders, and recent advances in state-of-art technologies for exosome detection and isolation will be reviewed along with future research directions and challenges regarding the manipulation and genetic engineering of exosomes for potential in vitro and in vivo disease diagnosis approaches.

6.
Front Chem ; 10: 943003, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105306

RESUMO

In this study, two novel biomimetic modular peptide motifs based on the alpha-2 subunit of type IV collagen (CO4A2) were designed and immobilized on a graphene platform to imitate integrin and heparan sulfate- (HS-) binding proteins. The in silico study was used to design 9-mer K[KGDRGD]AG and 10-mer KK[SGDRGD]AG for testing designed Integrin-Binding Peptide (dIBP) and HS-Binding Peptide (dHBP). The virtual docking technique was used to optimize the peptide motifs and their relevant receptors. Molecular dynamic (MD) simulation was used to evaluate the stability of peptide-receptor complexes. The effect of the platform on the differentiation of human mesenchymal stem cells (hMSCs) to hepatic-like cells (HLCs) was evaluated. After differentiation, some hepatic cells' molecular markers such as albumin, AFP, CK-18, and CK-19 were successfully followed. Graphene-heparan sulfate binding peptide (G-HSBP) enhances the mature hepatic markers' expression instead of control (p ≤ 0.05). The pathological study showed that the designed platform is safe, and no adverse effects were seen till 21 days after implantation.

7.
J Diabetes Metab Disord ; 21(2): 1763-1783, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35891981

RESUMO

With the unexpected emergence of the novel 2019 Wuhan coronavirus, the world was faced with a sudden uproar that quickly shifted into a serious life-threatening pandemic. Affecting the lives of the global population and leaving drastic damage in various sections and systems, several measures have been constantly taken to tackle down this crisis. For instance, numerous vaccines have been developed in the past two years, some of which have been granted emergency use, thus providing sufficient immunity to the vaccinated individuals. However, the appearance of newly emerged SARS-CoV-2 variants with accelerated transmission and fatality has led the world towards another pandemic. Having undergone various mutations in genomic and/or amino acid profiles, some of the emerged variants of concern (VOCs) including Alpha, Beta, Gamma, and Delta have displayed immune evasion and pathogenicity even in the vaccinated population, hence raising concerns regarding the efficacy of current vaccines against new VOCs of COVID-19. Therefore, genomic investigations of SARS-CoV-2 mutations are expected to provide valuable insight into the evolution of SARS-CoV-2, while also determining the impact of different mutations on infection severity. This study was constructed with the aim of shining light on recent advances regarding mutations in major COVID-19 VOCs, as well as vaccination efficacy against those VOCs.

8.
Artigo em Inglês | MEDLINE | ID: mdl-35666794

RESUMO

An efficient inverse optimal control method named Adaptive Reference IOC is introduced to study natural walking with musculoskeletal models. Adaptive Reference IOC utilizes efficient inner-loop direct collocation for optimal trajectory prediction along with a gradient-based weight update inspired by structured classification in the outer-loop to achieve about 7 times faster convergence than existing derivative-free methods while maintaining similar outcomes in terms of gait trajectory matching. The proposed method adequately reconstructed the reference data when applied to experimental walking data from ten participants walking at various speeds and stride lengths. The proposed framework can facilitate efficient personalized cost function optimization for specific walking tasks, and provide guidance to personalized reference trajectory design for assistive robotic systems such as lower-limb exoskeletons.


Assuntos
Exoesqueleto Energizado , Caminhada , Fenômenos Biomecânicos , Marcha , Humanos , Músculo Esquelético
9.
PLoS One ; 17(4): e0265619, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35363774

RESUMO

BACKGROUND: Extracellular vesicles (EVs), including exosomes and microvesicles, are involved in intercellular communication by transferring biomolecules such as mRNA, which has been shown to be as essential biomarkers for many physiological and pathological conditions such as diabetic nephropathy (DN). This study aimed to investigate the expression of CDH1, CDH2, MCP-1, and PAI-1 mRNAs in blood EVs of DN patients and to determine their accuracy in predicting early-stage DN. METHODS: We recruited 196 participants, including 35 overt DN patients, 53 incipient DN patients, 62 diabetic patients (DM), and 46 healthy individuals. Quantification of the mRNA profile of blood EVs was performed using the qRT-PCR method. The diagnostic performance of mRNA was evaluated using receiver operating characteristic analysis. RESULTS: The mRNA expression of CDH2 and MCP-1 was downregulated in overt DN group (0.22-fold change and 0.15-fold change, respectively) and incipient DN group (0.60-fold change and 0.43-fold change, respectively) compared to DM group (1.72-fold change and 2.77-fold change, respectively), while PAI-1 mRNA expression decreased in incipient DN group (0.70-fold change) and DM group (0.58-fold change) compared to control. However, the expression level of CDH1 mRNA was not significantly different among the four groups (p = 0.408). Moreover, CDH2 and MCP-1 mRNAs inversely correlated with creatinine (r = -0.370 and r = -0.361, p<0.001) and Alb/Cr ratio (r = -0.355 and r = -0.297, p<0.001). 1/CDH2 mRNA also predicted overt DN with an accuracy of 0.75 (95%CI: 0.65-0.85) and incipient DN with an accuracy of 0.61 (95%CI: 0.50-0.71) while 1/MCP-1 mRNA had an accuracy of 0.66 (95%CI: 0.55-0.77) for overt DN prediction and an accuracy of 0.61 (95%CI: 0.51-0.71) for incipient DN prediction. CONCLUSION: CDH2 and MCP-1 mRNAs expression in blood EVs was decreased with the development of DN, suggesting the renoprotective effect of these mRNAs in diabetic individuals. Moreover, their quantifications could serve as diagnostic biomarkers for early-stage DN.


Assuntos
Antígenos CD , Caderinas , Quimiocina CCL2 , Nefropatias Diabéticas , Vesículas Extracelulares , Antígenos CD/genética , Biomarcadores , Caderinas/genética , Quimiocina CCL2/genética , Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/genética , Vesículas Extracelulares/metabolismo , Humanos , Inibidor 1 de Ativador de Plasminogênio , Proteinúria , RNA Mensageiro/genética
10.
Diabetes Metab Syndr ; 16(4): 102450, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35344849

RESUMO

BACKGROUND AND AIMS: Exosome as a novel biomarker reflecting cell behavior in normal and pathological conditions such as diabetes is being the center of academic attention. Therefore, we aimed to study the research output of exosome in diabetes globally. METHODS: We conducted a bibliometric approach to analyze publications on exosome and diabetes from the beginning to 2021 based on keyword search in the Scopus. Annual publications, citations, contributions, co-authorships, and co-occurrences were analyzed and plotted using VOSviewer and GraphPad Prism. RESULTS: 410 original articles and 149 reviews have published between 2009 and 2021. China and the USA were top countries in research output, sponsorship, and international collaborations. The top journals were Scientific Reports, Stem Cell Research and Therapy and Diabetes. The top institution was the University of Queensland in Australia. The top author was Chopp M. Co-occurrence analysis indicated that researchers focused on 1) extracellular vesicles in insulin resistance induced by metabolic disorders like obesity and diabetes mellitus; 2) diagnostic applicability of exosomal microRNAs as biomarkers for diabetic nephropathy; 3) therapeutic effect of exosome in wound healing and endothelial dysfunction during diabetes mellitus; and 4) The oxidative stress, autophagy, apoptosis, fibrosis, inflammation and angiogenesis mediated by exosomes during diabetes. CONCLUSION: The trend in research output has been increased in this field, and advanced countries are involved much more than other countries in terms of research, financial support, and international collaboration. The bibliometric results could be beneficial for further studies in better understanding of novel ideas in exosome and diabetes fields.


Assuntos
Diabetes Mellitus , Exossomos , Bibliometria , Biomarcadores , Diabetes Mellitus/terapia , Humanos , Publicações
11.
Diabetes Metab Syndr ; 15(5): 102250, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34419857

RESUMO

AIMS: Due to the importance of omics approaches in diabetes diagnosis, we were assumed to study the scientific activities on omics and type 2 diabetes worldwide. METHOD: Bibliometric approach was utilized to evaluate the documents on proteomics, lipidomics, and metabolomics in patients with type 2 diabetes in the Scopus database from the beginning to 2020. The articles were screened by two reviewers and the number of publications and citations on omics and type 2 diabetes, top-ranked journals, top-cited articles, country co-contributions, co-authorships, author keywords, and terms were analyzed. RESULTS: The scientific publications in this field consisted of 551 original articles, of which the USA shares the most percent, followed by China and Germany. The frequent keywords showed that the following hotspots were of interest: "Metabolomics, proteomics, and lipidomics as biomarkers for diabetes", "Omics and diabetic nephropathy", "The application of omics in obesity, insulin resistance, and type 2 diabetes". CONCLUSION: This study showed an increasing trend in applying omics in type 2 diabetes researches and determined the leading producers in this field. Besides, the research hotspots and the main subjects of documents were provided for future research and policy decision-making.


Assuntos
Bibliometria , Biomarcadores/metabolismo , Diabetes Mellitus Tipo 2/diagnóstico , Lipidômica/estatística & dados numéricos , Metaboloma , Proteoma/metabolismo , Biomarcadores/análise , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Prognóstico , Proteoma/análise
12.
Res Pharm Sci ; 16(3): 315-325, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34221065

RESUMO

BACKGROUND AND PURPOSE: The new coronavirus (Covid-19) has resulted in great global concerns. Due to the mortality of this virus, scientists from all over the world have been trying to employ different strategies to tackle down this concern. This virus enters cells via phagocytosis through binding to the angiotensin-converting enzyme II receptor. After invading the body, it can stay hidden in there for a period of up to 24 days (incubation period). EXPERIMENTAL APPROACH: In this report, by the use of in silico studies we selected several FDA-approved compounds that possess antiviral properties. We chose the viral Spike protein as the target of drug compounds and carried out the screening process for the FDA databank in order to find the most effective ligand. FINDINGS/RESULTS: The results from dock and MD revealed 10 compounds with high affinity to the receptor-binding domain motif of S protein. The best inhibitors were the ingredients of Depinar, which managed to effectively block the interactions between cells and virus. CONCLUSION AND IMPLICATION: The results of this study were approved by in silico studies and due to the lack of time; we did not test the efficiency of these compounds through in vitro and in vivo studies. However, the selected compounds are all FDA approved and some are supplements like vitamin B12 and don't cause any side effects for patients.

13.
J Transl Med ; 19(1): 299, 2021 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-34246281

RESUMO

BACKGROUND: Diabetic nephropathy (DN) has an increasing global prevalence with excessive health expenditure and burden. Exosomal mRNAs regulate intercellular communications and participate in the pathogenesis of various disorders like DN. This study aimed to assess the expression levels of ACE, ELMO1, and WT1 mRNAs in the blood extracellular vesicles (EVs) of DN patients and diabetic patients without nephropathy (DM group) in comparison to healthy controls and investigate their correlations with the severity of DN. METHODS: The performed investigation is a cross-sectional study of 256 participants including 103 DN patients, 100 DM patients, and 53 healthy controls. The quantification of WT1, ACE, and ELMO1 mRNAs in the blood EVs were executed using qRT-PCR. The ROC analysis was performed to determine the diagnostic accuracy of mRNAs. RESULTS: DN patients had significantly higher expressed WT1 mRNA (1.70-fold change) and lower expressed ACE mRNA (0.55-fold change) in the blood EVs compared to DM patients and controls. ELMO1 mRNA was not expressed in EVs of any groups. A positive correlation between WT1 mRNA level and urine Alb/Cr ratio (r = 0.602, p < 0.001) and a negative correlation between ACE mRNA expression and urine Alb/Cr ratio within DN patients (r = - 0.474, p < 0.001) was identified. The accuracy of WT1 mRNA and 1/ACE mRNA for predicting incipient DN was 0.63 (95% CI 0.55, 0.72) and 0.62 (95% CI 0.54, 0.71), and for predicting overt DN was 0.83 (95% CI 0.74, 0.92) and 0.75 (95% CI 0.66, 0.83), respectively. CONCLUSIONS: WT1 and ACE mRNAs level in blood EVs were predictors for early diagnosis of DN therefore their quantifications might be used to determine the severity of albuminuria and glomerular injuries.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Vesículas Extracelulares , Proteínas Adaptadoras de Transdução de Sinal , Albuminúria , Biomarcadores , Estudos de Casos e Controles , Estudos Transversais , Nefropatias Diabéticas/genética , Humanos , Peptidil Dipeptidase A , RNA Mensageiro/genética , Proteínas WT1
14.
Sci Rep ; 11(1): 13790, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215792

RESUMO

A pseudohomogeneous carrier as an emerging term refers to subnanometric carbon-based vehicle with a high ability to interact with genetic materials to form stable carboplex and successfully transfer them into the cell which will result in inhibiting or expressing of therapeutic genes. Chitosan is a non-toxic polyaminosaccharide used as a precursor in the presence of citric acid to produce carbon quantum dots (CQDs), which decorated with arginine as a surface passivation agent with high amine density in hydrothermal methodology. The Arginine-CQDs are comprehensively characterized by Fourier-transform infrared spectroscopy (FT-IR), Ultraviolet-visible spectroscopy (UV-vis), Atomic force microscopy (AFM), field emission scanning electron microscope (FE-SEM), Energy-dispersive X-ray (EDX) mapping, fluorescence, High-resolution transmission electron microscopy (HR-TEM), zeta potential and X-ray powder diffraction (XRD). In this regard, for the first time, carboplex are formed by electrostatic conjugating of Arginine-CQDs with DNA to protect it from enzymatic degradation. Moreover, the carboplex, like the chitosan precursor, has not shown toxicity against AGS cell line. Interestingly, the Arginine-CQDs have exhibited an excellent ability to overcome cell barriers to deliver into cells compared to chitosan at the same weight ratio. The Arginine-CQDs/pEGFP (W/W) nanocomplex, not only lead to transfection with a relatively higher efficiency than PEI polymer, which is the "golden standard", but carboplex also demonstrates no significant toxicity. Indeed, the EGFP expression level has reached to 2.4 ± 0.2 via Arginine-CQDs carboplex at W/W 50 weight ratio. To the best of our knowledge, this is the first report includes chitosan-based CQDs functionalized by arginine which is applied to serve as a pseudohomogeneous vehicle for gene transfection.


Assuntos
Arginina/genética , Carbono/química , Proteínas de Fluorescência Verde/genética , Nanopartículas/química , Arginina/química , Quitosana/química , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Transferência de Genes , Humanos , Microscopia de Força Atômica , Pontos Quânticos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Transfecção/métodos
15.
BMC Med Inform Decis Mak ; 20(1): 291, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33167984

RESUMO

BACKGROUND: Akkermansia muciniphila is an anaerobic bacterium residing in the healthy intestinal tract of host and its quantity has a negative correlation with various host diseases. This study for the first time provides a holistic bibliometric aspect of Akkermansi muciniphila research in the literature and shows the hot topic terms of these articles in any period of time. METHODS: Scopus database was selected to retrieve documents relevant to Akkermansia muciniphila in any language up to 2019. The bibliometric profile of Akkermansia muciniphila articles including subject area, year distribution, citations, institutions, journals, authors, and countries was systematically characterized and the collaboration networks of authors and countries as well as the burst detection algorithm of the words in the titles, abstracts and keywords were visualized. RESULTS: There is a progressive growing trend in research on Akkermansia from 2004 to 2019 with a total of 566 articles during this period. Out of 353 original articles, there are 194 animal studies (155 studies on mice) and 112 human studies. Also, 65 various diseases were investigated in these studies. The most focused conditions are obesity (71 articles) and type2 diabetes (39 articles). The United States is the leading country on Akkermansia publications (n = 132), followed by China (n = 95). Frontiers in Microbiology is the most dominant journal with 23 Akkermansia publications. In addition, "cancer" is the hot topic of recent Akkermansia research. CONCLUSION: Akkermansia research is of progressive interest during the last decade and the studies on this subject move towards its relationship with cancer and its promising effect on health.


Assuntos
Bibliometria , Publicações Periódicas como Assunto/estatística & dados numéricos , Akkermansia , Animais , China , Camundongos , Editoração , Pesquisa , Estados Unidos
16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3178-3183, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018680

RESUMO

With the aging population and rising rates of mobility disability, the demand for advanced smart rollators is increasing. To design control systems which improve safety and reliability, accurate prediction of human intent is required. In this paper, we present a classification method to predict intent of the rollator user using indirect inputs. The proposed classification algorithm uses data collected from an inertial measurement unit and an encoder implemented into a rollator. The developed intent estimation method is experimentally verified on our modified robotic platform. For our experiment with 7 healthy young adults, KNN classification algorithm was able to predict 3 intents (turn left, turn right and walk straight) with 92.9 % accuracy.


Assuntos
Intenção , Andadores , Idoso , Humanos , Aprendizagem , Reprodutibilidade dos Testes , Caminhada , Adulto Jovem
17.
Med J Islam Repub Iran ; 34: 51, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32934940

RESUMO

Background: Since the outbreak of the novel coronavirus disease from Wuhan, China, in early December 2019, many scientists focused on this infection to find a way to deal with it. Due to the dramatic scientific growth in this field, we conducted a scientometric study to gain a better understanding of the scientific literature on COVID-19. Methods: We extracted all COVID-19 documents indexed in the Scopus from December 1, 2019, to April 1, 2020, without any language limitation and determined their bibliometric characteristics, including document type, open accessibility status, citation counting, H-index, top cited documents, the most productive countries, institutions and journals, international collaboration, the most frequent terms and keywords, journal bibliographic coupling and cocitations. Results: A total of 923 documents on COVID-19 were retrieved, of which 418 were original articles. All documents had received 2551 citations with an average citation of 2.76 per document and an h-index of 23. China ranked first with 348 documents, followed by the United States (n = 160). The Lancet and BMJ Clinical Research Ed published the most documents (each with 74 documents) and 2 institutions (University of Hong Kong and Huazhong University of Science and Technology) ranked first in this regard. In addition, the present study analyzed the top 25 highly-cited documents (those that had received 70% of all citations). Conclusion: This study highlighted the focused subjects on various aspects of COVID-19 literature such as pathogenesis, epidemiology, transmission, diagnosis, treatment, prevention, and its complications.

18.
Int J Nanomedicine ; 15: 6201-6209, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32884270

RESUMO

BACKGROUND: Unique properties of graphene and its derivatives make them attractive in the field of nanomedicine. However, the mass application of graphene might lead to side effects, which has not been properly addressed in previous studies, especially with regard to its effect on the cell cycle. METHODS: The effect of two concentrations (100 and 200 µg/mL) of nano- and microsized graphene oxide (nGO and mGO) on apoptosis, cell cycle, and ROS generation was studied. The effect of both sizes on viability and genotoxicity of the embryonic fibroblast cell cycle was evaluated. MTT and flow cytometry were applied to evaluate the effects of graphene oxide (GO) nanosheets on viability of cells. Apoptosis and cell cycle were analyzed by flow cytometry. RESULTS: The results of this study showed that GO disturbed the cell cycle and nGO impaired cell viability by inducing cell apoptosis. Interestingly, both nGO and mGO blocked the cell cycle in the S phase, which is a critical phase of the cell cycle. Upregulation of TP53-gene transcripts was also detected in both nGO- and mGO-treated cells compared to the control, especially at 200 µg/mL. DNA content of the treated cells increased; however, because of DNA degradation, its quality was decreased. CONCLUSION: In conclusion, graphene oxide at both nano- and micro-scale damages cell physiology and increases cell population in the S phase of the cell cycle.


Assuntos
Ciclo Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Grafite/farmacologia , Nanoestruturas/toxicidade , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Embrião de Mamíferos/citologia , Fibroblastos/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Grafite/toxicidade , Camundongos , Testes de Mutagenicidade , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/genética
19.
Mater Sci Eng C Mater Biol Appl ; 106: 110259, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753381

RESUMO

Polymeric hydrogel-based 3D scaffolds are well-known structures, being used for cultivation and differentiation of stem cells. However, scalable systems that provide a native-like microenvironment with suitable biological and physical properties are still needed. Incorporation of nanomaterials into the polymeric systems is expected to influence the physical properties of the structure but also the stem cells fate. Here, alginate/gelatin hydrogel beads incorporated with mesoporous silica nanoparticles (MSNs) (average diameter 80.9 ±â€¯10 nm) and various surface chemistries were prepared. Human adipose-derived mesenchymal stem cells (hASCs) were subsequently encapsulated into the alginate/gelatin/silica hydrogels. Incorporation of amine- and carboxyl-functionalized MSNs (A-MSNs and C-MSNs) significantly enhances the stability of the hydrogel beads. In addition, the expression levels of Nanog and OCT4 imply that the incorporation of A-MSNs into the alginate/gelatin beads significantly improves the proliferation and the stemness of encapsulated hASCs. Importantly, our findings show that the presence of A-MSNs slightly suppresses in vivo inflammation. In contrast, the results of marker gene expression analyses indicate that cultivation of hASCs in alginate beads incorporated with C-MSNs (10% w/w) leads to a heterogeneously differentiated population of the cells, i.e., osteocytes, chondrocytes, and adipocytes, which is not appropriate for both cell culture and differentiation applications.


Assuntos
Técnicas de Cultura de Células/métodos , Hidrogéis/química , Nanopartículas/química , Dióxido de Silício/química , Tecido Adiposo/citologia , Alginatos/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Técnicas de Cultura de Células/instrumentação , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Gelatina/química , Humanos , Hidrogéis/farmacologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Proteína Homeobox Nanog/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Porosidade , Ratos , Ratos Wistar , Alicerces Teciduais/química
20.
Colloids Surf B Biointerfaces ; 184: 110543, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31627102

RESUMO

In this paper, a bottom-up hydrothermal route is reported for the synthesis of oxygen and nitrogen co-decorated carbon quantum dots (CQDs) using ammonium hydrogen citrate (AHC) as a single precursor. DLS data approved the formation of 4.0 nm (average size) CQDs. XRD pattern shows the interlayer spacing (002) of 3.5 Šfor CQDs, which is exactly the same as that of crystalline graphite. XPS and FTIR spectra verified the formation of oxygen and nitrogen functional groups on the CQDs surface. Co-decorated carboxyl, hydroxyl and amine groups on the CQDs surfaces make them as promising polyelectrolyte for gene delivery. Toxicity assay showed a survival rate of 70% under different incubation times and up to 500 µg/mL. The highly water-soluble, stable fluorescence and low toxic CQDs increased the gene expression of DNA plasmid in E. coli bacteria 4-fold more than the control group.


Assuntos
Carbono/química , DNA/química , Nitrogênio/química , Oxigênio/química , Pontos Quânticos/química , Carbono/farmacologia , Citratos/química , DNA/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Técnicas de Transferência de Genes , Nitrogênio/farmacologia , Oxigênio/farmacologia , Tamanho da Partícula , Plasmídeos , Polieletrólitos/química , Polieletrólitos/farmacologia , Compostos de Amônio Quaternário/química , Propriedades de Superfície
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