Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 67
Filtrar
Mais filtros

Base de dados
Tipo de documento
País/Região como assunto
Intervalo de ano de publicação
1.
J Indian Assoc Pediatr Surg ; 27(3): 351-353, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35733598

RESUMO

We describe a 3-month-old baby who presented with a nonresolving pneumonia which failed to respond to antibiotic therapy. An underlying congenital pulmonary adenomatous malformation was suspected. On thoracotomy, she was found to have a tuberculous mediastinal abscess which was drained. Mediastinal abscess is a rare occurrence in childhood tuberculosis.

2.
Biotechnol Bioeng ; 118(12): 4590-4622, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34599764

RESUMO

Several approaches for elimination of oral pathogens are being explored at the present time since oral diseases remain prevalent affecting approximately 3.5 billion people worldwide. Need for antimicrobial biomaterials in dental healthcare include but is not restricted to designing resin composites and adhesives for prevention of dental caries. Constant efforts are also being made to develop antimicrobial strategies for clearance of endodontic space prior root canal treatment and for treatment of periimplantitis and periodontitis. This article discusses various conventional and nanotechnology-based strategies to achieve antimicrobial efficacy in dental biomaterials. Recent developments in the design and synthesis of antimicrobial peptides and antifouling zwitterionic polymers to effectively lessen the risks of antimicrobial drug resistance are also outlined in this review. Further, the role of contemporary strategies such as use of smart biomaterials, ionic solvent-based biomaterials and quorum quenchers incorporated biomaterials in the elimination of dental pathogens are described in detail. Lastly, we mentioned the approach of using polymers to print custom-made three-dimensional antibacterial dental products via additive manufacturing technologies. This review provides a critical perspective on the chemical, biomimetic, and engineering strategies intended for developing antimicrobial biomaterials that have the potential to substantially improve the dental health.


Assuntos
Anti-Infecciosos , Materiais Biocompatíveis , Materiais Dentários , Saúde Bucal , Animais , Peptídeos Antimicrobianos , Cárie Dentária/prevenção & controle , Humanos , Camundongos , Nanoestruturas , Impressão Tridimensional
3.
Sensors (Basel) ; 21(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34502636

RESUMO

Brain-Computer Interface (BCI) is an advanced and multidisciplinary active research domain based on neuroscience, signal processing, biomedical sensors, hardware, etc. Since the last decades, several groundbreaking research has been conducted in this domain. Still, no comprehensive review that covers the BCI domain completely has been conducted yet. Hence, a comprehensive overview of the BCI domain is presented in this study. This study covers several applications of BCI and upholds the significance of this domain. Then, each element of BCI systems, including techniques, datasets, feature extraction methods, evaluation measurement matrices, existing BCI algorithms, and classifiers, are explained concisely. In addition, a brief overview of the technologies or hardware, mostly sensors used in BCI, is appended. Finally, the paper investigates several unsolved challenges of the BCI and explains them with possible solutions.


Assuntos
Interfaces Cérebro-Computador , Algoritmos , Encéfalo , Eletroencefalografia , Processamento de Sinais Assistido por Computador , Interface Usuário-Computador
4.
J Indian Assoc Pediatr Surg ; 26(5): 348-350, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34728925

RESUMO

We report a 4-month-old baby presenting with bilateral congenital lobar emphysema. A two-staged bilateral lobectomy was planned, but bilateral lobectomy had to be performed as a single-staged procedure. Data are scarce on the appropriate approach to children with bilateral involvement. Both single-staged and two-staged procedures have shown variable success.

5.
Soft Matter ; 16(6): 1404-1454, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31984400

RESUMO

In this review, we focus on the very recent developments on the use of the stimuli responsive properties of polymer hydrogels for targeted drug delivery, tissue engineering, and biosensing utilizing their different optoelectronic properties. Besides, the stimuli-responsive hydrogels, the conducting polymer hydrogels are discussed, with specific attention to the energy generation and storage behavior of the xerogel derived from the hydrogel. The electronic and ionic conducting gels have been discussed that have applications in various electronic devices, e.g., organic field effect transistors, soft robotics, ionic skins, and sensors. The properties of polymer hybrid gels containing carbon nanomaterials have been exemplified here giving attention to applications in supercapacitors, dye sensitized solar cells, photocurrent switching, etc. Recent trends in the properties and applications of some natural polymer gels to produce thermal and acoustic insulating materials, drug delivery vehicles, self-healing material, tissue engineering, etc., are discussed. Besides the polymer gels, peptide gels of different dipeptides, tripeptides, oligopeptides, polypeptides, cyclic peptides, etc., are discussed, giving attention mainly to biosensing, bioimaging, and drug delivery applications. The properties of peptide-based hybrid hydrogels with polymers, nanoparticles, nucleotides, fullerene, etc., are discussed, giving specific attention to drug delivery, cell culture, bio-sensing, and bioimaging properties. Thus, the present review delineates, in short, the preparation, properties, and applications of different polymer and peptide hydrogels prepared in the past few years.


Assuntos
Hidrogéis/química , Peptídeos/química , Polímeros Responsivos a Estímulos/química
6.
Org Biomol Chem ; 18(34): 6716-6723, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32820796

RESUMO

An innovative fluorescein appended naphthalene diimide based probe (FANDI) has been prepared and characterized to selectively recognize hypochlorite or ClO- ions in the presence of other reactive oxygen species (ROS) and biorelevant ions, using a unique chemodosimetric method. Hypochlorite induced oxidation can efficiently alter the initial photophysical properties of FANDI and shows an easily detectable "turn on" green fluorescence. The chemodosimeter FANDI can efficiently detect exogenous as well as endogenous ClO- ions in RAW 264.7 cells (macrophages) and zebrafish embryos (Danio rerio) which further ensures the high potential, easy cell permeability and photostability of FANDI and makes it worth exploring in the future.


Assuntos
Ácido Hipocloroso
7.
Org Biomol Chem ; 17(21): 5230-5233, 2019 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-30990508

RESUMO

A p-nitrophenyl based rhodamine probe (NPRB) has been designed and synthesized for the selective, real-time detection of Al(iii) in aqueous medium with a lower micromolar range detection limit at physiological pH. All the spectroscopic and theoretical analyses validated the proposed 1 : 1 complexation between NPRB and Al3+ along with an 80-fold enhancement in fluorescence intensity. Using the "turn on" response of the probe, binding of NPRB to Al3+ in the brain tissue of adult male zebrafish (D. rerio) has been visualized through fluorescence microscopy.


Assuntos
Alumínio/análise , Encéfalo/diagnóstico por imagem , Corantes Fluorescentes/química , Imagem Óptica , Rodaminas/química , Peixe-Zebra , Animais , Íons/análise , Masculino , Microscopia de Fluorescência
8.
Anal Bioanal Chem ; 411(23): 6203-6212, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300856

RESUMO

Cysteine is a crucial amino acid, found in a huge amount in protein-rich foods. We focused our research to determine the amount of free cysteine consumed highly in foods such as pork, beef, poultry, eggs, dairy, red peppers, soybeans, broccoli, brussels sprouts, oats, and wheat germs. A newly designed carbazole-pyridine-based fluorescent probe (CPI) has been introduced for quantitative estimation of cysteine (Cys) with a "turn on" fluorescence in some popular processed food samples chosen from our daily diet. CPI shows both naked eye and UV-visible color changes upon interaction with cysteine. The binding approach between CPI and Cys at biological pH has been thoroughly explored by UV-visible and fluorescence spectroscopy. From Job's plot analysis, 1:1 stoichiometric reaction between CPI and Cys is observed with a detection limit of 3.8 µM. NMR, ESI mass spectrometry, and time-dependent density functional theory (TD-DFT) study enlightens the formation of more stable product CPI-Cys. The "turn on" response of the probe CPI occurs due to the interruption of intra-molecular charge transfer (ICT) process upon reacting with cysteine. Moreover, CPI is a very stable, cost-effective compound and exhibits excellent real-time selectivity towards Cys over all other comparative biorelevant analytes. Interestingly, our proposed method is much advantageous as it is able to estimate cysteine predominantly by screening out other comparative biocomponents found in different protein-rich foods.


Assuntos
Carbazóis/química , Cisteína/análise , Corantes Fluorescentes/química , Análise de Alimentos/métodos , Piridinas/química , Limite de Detecção , Modelos Moleculares , Espectrometria de Fluorescência/métodos
9.
Chemistry ; 24(21): 5591-5600, 2018 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-29411906

RESUMO

Detection of nitroaromatics at ultralow concentration is a major security concern in defense, forensics, and environmental science. To this end, a new triarylamine-cored dendritic gelator (OGR) was synthesized, which produced thermoreversible, thixotropic, and fluorescent gels in n-octanol. On gelation, both π-π* transitions and the emission peak of the gelator show redshifts with a 4.5-fold increase of fluorescence intensity in the gel state indicating J-aggregation. The nitrogen lone-pair electrons of OGR make it a donor, and electron transfer occurs to acceptor nitroaromatics causing fluorescence quenching, which is further promoted due to its acidity. The Stern-Volmer rate constants measured for different nitroaromatics showed that it senses picric acid (PA) best. The contact-mode technique with OGR-treated paper strips can allow naked-eye detection of PA under UV light down to 10-11 m concentration within 30 s. Reusability of the gel is achieved by treating OGR@PAx with NaOH solution. Impedance spectroscopic results indicated a decrease of both charge-transport resistance and Warburg impedance on successive addition of PA. The limits of detection of PA determined from fluorescence and impedance measurements match well. Thus, the OGR gel is a reusable, low-cost, specific sensor for PA by naked-eye colorimetric, fluorescence, and impedance techniques.


Assuntos
Aminas/química , Géis/química , Picratos/análise , Colorimetria , Corantes/química , Elétrons , Fluorescência , Fluorometria
10.
Langmuir ; 34(41): 12401-12411, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30234308

RESUMO

Tuning the electronic structure of a π-conjugated polymer from the responsive side chains is generally done to get desired optoelectronic properties, and it would be very fruitful when light is used as an exciting tool that can also affect the backbone chain conformation. For this purpose, polythiophene- g-poly-[ N-(6-methyluracilyl)- N, N-dimethylamino chloride]ethyl methacrylate (PTDU) is synthesized. On exposure to diffuse sunlight, the uracil moieties of the grafted chains cause the absorption maximum of PTDU solution to show gradual blue shift of 87 nm and a gradual blue shift of 46 nm in the emission maximum, quenching its fluorescence with time. These effects occur specifically at the absorption range of polythiophene (PT) chromophore on direct exposure of light of different wavelengths, and the optimum wavelength is found to be 420 nm. Impedance study suggests a decrease in charge transfer resistance upon exposure because of conformational change of PTDU. Theoretical study indicates that on exposure to visible light, uracil moieties move toward the backbone to facilitate photoinduced electron transfer between the PT and the uracil, attributing to the variation in optoelectronic properties. Morphological and light-scattering studies exhibit a decrease in particle size because of coiling of the PT backbone and squeezing of the grafted chain on light exposure. The transparent orange-colored PTDU solution becomes hazy with a hike in emission intensity on addition of sodium halides and becomes reversibly transparent or hazy on heating or cooling. The screening of cationic centers of PTDU by varying halide anion concentration tunes the phase transition temperature. Thus, the light-induced variation in the backbone conformation is responsible for tuning the optoelectronic properties and regulates the thermos-responsiveness of the PTDU solution in the presence of halide ions.

11.
Anal Chem ; 89(24): 13054-13057, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29183127

RESUMO

Amino pyridine-based rhodamine conjugate (APR) has been developed as a first chemosensor for selective detection and quantification of L-4-Hydroxyproline (Hyp). The "turn-on" fluorescence property of the chemosensor makes it unique for easy estimation of Hyp in collagen and biological samples.


Assuntos
Colágeno/química , Corantes Fluorescentes/química , Hidroxiprolina/análise , Piridinas/química , Rodaminas/química , Teoria da Densidade Funcional , Corantes Fluorescentes/síntese química , Rodaminas/síntese química
12.
Langmuir ; 33(44): 12739-12749, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-29028346

RESUMO

A significant tuning of optoelectronic properties of polythiophene (PT) chains due to Hofmeister iodide (I-) ion is demonstrated in ampholytic polythiophene [polythiophene-g-poly{(N,N,N-trimethylamino iodide)ethyl methacrylate-co-methacrylic acid}, APT] at different pHs. In acidic medium, the absorption and emission signals of PT chromophore exhibit appreciable blue shift in the presence of I- as counteranion only. The cooperative effect of undissociated -COOH and quaternary ammonium groups immobilize I- near the apolar PT chain causing threading of grafted chains and hence twisting of the backbone attributing to the blue shift. As medium pH is increased, dethreading of the PT backbone occurs due to ionization of -COOH group, releasing quencher iodide ions from the vicinity of the PT chains resulting in a red shift in absorption and a sharp hike in fluorescence intensity (390 times) for an increase of excitons lifetime. With an increase of pH, morphology changes from a multivesicular aggregate with vacuoles to smaller size vesicles and finally to nanofibrillar network structure. Dethreading is also found when APT interacts with RNA showing a significant hike of fluorescence (22 times) for displacing iodide ions forming a nanofibrillar network morphology. Threading and dethreading also affect the resistance, capacitance, and Warburg impedance values of APT. Molecular dynamics simulation of a model APT chain in a water box supports the threading at lower pH where the iodide ions pose nearer to the PT chain than that at higher pH causing dethreading. So the influence of Hofmeister I- ion is established for tuning the optoelectronic properties of a novel PT based polyampholyte by changing pH or by conjugating with RNA.


Assuntos
RNA/química , Concentração de Íons de Hidrogênio , Polímeros , Tiofenos , Água
13.
Bioorg Chem ; 71: 315-324, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28285874

RESUMO

Naphthyridine-based fluorescent probe H1 was synthesized and characterized for the quantification and selective detection of Uric Acid (UA) in live cell. In presence of UA, H1 forms the specific host-guest complex mainly through intermolecular hydrogen bonding and aromatic stacking which produces "turn-off" fluorescence. The probe and UA is found to be 1:1 stoichiometry on the basis of absorption and fluorescence titrations. The probe H1 has been shown to detect UA up to 0.6µM at pH 7.4. DFT-TDDFT calculations were performed in order to demonstrate the sensing mechanism and the electronic properties of the receptor-donor complex. The selectivity was evaluated in Vero cells in the presence of UA with other purine derivatives, structurally similar to UA. It was found to exhibit no cytotoxicity effect in tested concentration of H1 and good membrane permeability for the detection of UA in living cell system. The unknown concentration of UA in serum and urine can be measured easily using the fluorescence property of probe H1.


Assuntos
Corantes Fluorescentes/química , Naftiridinas/química , Ácido Úrico/análise , Animais , Chlorocebus aethiops , Fluorescência , Modelos Moleculares , Imagem Óptica , Espectrometria de Fluorescência , Células Vero
14.
Langmuir ; 32(7): 1871-80, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26836971

RESUMO

In the quest to engineer the nanofibrillar morphology of folic acid (F) gel, poly(4-vinylpyridine-co-styrene) (PVPS) is judiciously integrated as a polymeric additive because of its potential to form H-bonding and π-stacking with F. The hybrid gels are designated as F-PVPSx gels, where x denotes the amount of PVPS (mg) added in 2 mL of F gel (0.3%, w/v). The assistance of PVPS in the gelation of F is manifested from the drop in critical gelation concentration and increased fiber diameter and branching of F-PVPSx gels compared to that of F gel. PVPS induces a magnificent improvement of mechanical properties: a 500 times increase of storage modulus and ∼62 times increase of yield stress in the F-PVPS5 gel compared to the F gel. The complex modulus also increases with increasing PVPS concentration with a maximum in F-PVPS5 gel. Creep recovery experiments suggest PVPS induced elasticity in the otherwise viscous F gel. The fluorescence intensity of F-PVPSx gels at first increases with increasing PVPS concentration showing maxima at F-PVPS5 gel and then slowly decreases. Gelation is monitored by time-dependent fluorescence spectroscopy, and it is observed that F and F-PVPSx gels exhibit perfectly opposite trend; the former shows a sigmoidal decrease in fluorescence intensity during gelation, but the latter shows a sigmoidal increase. The gelation rate constants calculated from Avrami treatment on the time-dependent fluorescence data manifest that PVPS effectively enhances the gelation rate showing a maximum for F-PVPS5 gel. The hybrid gel exhibit 5 orders increase of dc conductivity than that of F-gel showing semiconducting nature in the current-voltage plot. The Nyquist plot in impedance spectra of F-PVPS5 xerogel exhibit a depressed semicircle with a spike at lower frequency region, and the equivalent circuit represents a complex combination of resistance-capacitance circuits attributed to the hybrid morphology of the gel fibers.

15.
Langmuir ; 32(21): 5373-82, 2016 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-27159227

RESUMO

The organogel of (E)-N'-(anthracene-10-ylmethylene)-3,4,5-tris(dodecyloxy)benzohydrazide (I) in methyl cyclohexane having a fibrillar network structure exhibits excellent fluorescence, which decreases sharply with time upon photoirradiation at λ = 365 nm. It has been attributed to the transformation of the E isomer of I to the Z isomer, and the kinetics of E-Z isomerization are compared for the sol, gel, xerogel, and powder states. The rate constants at different temperatures are measured from Avrami plots and its increase with an increase in temperature, indicating temperature acts as a promoter for photoirradiated E-Z isomeization along the imine (C═N) bond. In the powder form, the rate constant values are the lowest compared to those of other states for all temperatures and the xerogels exhibit the highest rate of E-Z isomerization. The rate constants of sol and gel states mostly lie between the two. The wide-angle X-ray scattering pattern changes after ultraviolet (UV) irradiation with the generation of new sharp peaks whose intensities increase with an increase in irradiation time. A polarized optical microscopic study indicates formation of small crystalline dots on the fibers in the gels, dendritic morphology on the xerogel fibers, and large needlelike morphology at the surface boundary of the solid. The dried I gel exhibits a melting peak at 96.7 °C, but upon irradiation, two peaks are observed at 98.5 and 152.7 °C; the latter has been attributed to the melting of crystals of Z isomers. Similar higher melting peaks are observed both for the xerogel and for powders after UV irradiation; the powders exhibit the highest meting peak at 159.4 °C. Possible reasons for the variation of rate constant values in the four different states and the difference in morphology and melting points of crystals of Z isomers of I are discussed.

16.
Curr Probl Cardiol ; 49(1 Pt C): 102129, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37866419

RESUMO

Segmentation architectures based on deep learning proficient extraordinary results in medical imaging technologies. Computed tomography (CT) images and Magnetic Resonance Imaging (MRI) in diagnosis and treatment are increasing and significantly support the diagnostic process by removing the bottlenecks of manual segmentation. Cardiac Magnetic Resonance Imaging (CMRI) is a state-of-the-art imaging technique used to acquire vital heart measurements and has received extensive attention from researchers for automatic segmentation. Deep learning methods offer high-precision segmentation but still pose several difficulties, such as pixel homogeneity in nearby organs. The motivated study using the attention mechanism approach was introduced for medical images for automated algorithms. The experiment focuses on observing the impact of the attention mechanism with and without pretrained backbone networks on the UNet model. For the same, three networks are considered: Attention-UNet, Attention-UNet with resnet50 pretrained backbone and Attention-UNet with densenet121 pretrained backbone. The experiments are performed on the ACDC Challenge 2017 dataset. The performance is evaluated by conducting a comparative analysis based on the Dice Coefficient, IoU Coefficient, and cross-entropy loss calculations. The Attention-UNet, Attention-UNet with resnet50 pretrained backbone, and Attention-UNet with densenet121 pretrained backbone networks obtained Dice Coefficients of 0.9889, 0.9720, and 0.9801, respectively, along with corresponding IoU scores of 0.9781, 0.9457, and 0.9612. Results compared with the state-of-the-art methods indicate that the methods are on par with, or even superior in terms of both the Dice coefficient and Intersection-over-union.


Assuntos
Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Humanos
17.
Mater Horiz ; 11(3): 661-679, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-37830433

RESUMO

Bacterial infections caused by Staphylococcus aureus are one of the growing concerns for human health care management globally. Antibiotic-associated adverse effects and the emergence of bacterial resistant strains necessitate the development of an alternative yet effective approach. Nanoemulsion-based therapy has emerged as a potential therapeutic strategy to combat bacterial infestation. Herein, we designed a cationic metal nanoparticle-conjugated fusogenic nanoemulsion (CFusoN) as a lipid solubilizing nanovesicle for the effective treatment of S. aureus infection with a killing efficiency of 99.999%. The cationic nanoparticle-conjugated nanoemulsion (viz. NECNP) (24.4 ± 2.9 mV) electrostatically bound with the negatively charged bacterial cell membrane (-10.2 ± 3.7 mV) causing alteration of the bacterial surface charge. The fluorometric and flow cytometry studies confirmed the bacterial membrane depolarization and altered cell membrane permeability leading to cell death. The atomic force microscopic studies further demonstrated the damage of the cellular ultrastructure, while the transmission electron microscopic image and membrane lipid solubilization analysis depicted the solubilization of the bacterial membrane lipid bilayer along with the leakage of the intracellular contents. The cell membrane fatty acid analysis revealed that the methyl esters of palmitic acid, stearic acid and octadecadienoic acid isomers were solubilized after the treatment of S. aureus with CFusoN. The bactericidal killing efficiency of CFusoN is proposed to occur through the synergistic efficacy of the targeted attachment of CNP to the bacterial cells along with the lipid solubilization property of NE. Interestingly, NECNP didn't elicit any in vitro hemolytic activity or cytotoxicity against red blood cells (RBCs) and L929 fibroblast cells, respectively, at its bactericidal concentration. Furthermore, a porcine skin wound infection model exhibited the enhanced wound cleansing potency of CFusoN in comparison to the commercially available wound cleansers. The obtained antibacterial activity, biocompatibility and skin wound disinfection efficacy of the NECNP demonstrated the formulation of a cell targeted CFusoN as a promising translatable strategy to combat bacterial infection.


Assuntos
Nanopartículas , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Nanopartículas/uso terapêutico , Nanopartículas/química , Bactérias , Lipídeos de Membrana/farmacologia , Lipídeos de Membrana/uso terapêutico
18.
Sci Rep ; 14(1): 5634, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454122

RESUMO

In these studies, we designed and investigated the potential anticancer activity of five iron(II) cyclopentadienyl complexes bearing different phosphine and phosphite ligands. All complexes were characterized with spectroscopic analysis viz. NMR, FT-IR, ESI-MS, UV-Vis, fluorescence, XRD (for four complexes) and elemental analyses. For biological studies, we used three types of cells-normal peripheral blood mononuclear (PBM) cells, leukemic HL-60 cells and non-small-cell lung cancer A549 cells. We evaluated cell viability and DNA damage after cell incubation with these complexes. We observed that all iron(II) complexes were more cytotoxic for HL-60 cells than for A549 cells. The complex CpFe(CO)(P(OPh)3)(η1-N-maleimidato) 3b was the most cytotoxic with IC50 = 9.09 µM in HL-60 cells, IC50 = 19.16 µM in A549 and IC50 = 5.80 µM in PBM cells. The complex CpFe(CO)(P(Fu)3)(η1-N-maleimidato) 2b was cytotoxic only for both cancer cell lines, with IC50 = 10.03 µM in HL-60 cells and IC50 = 73.54 µM in A549 cells. We also found the genotoxic potential of the complex 2b in both types of cancer cells. However, the complex CpFe(CO)2(η1-N-maleimidato) 1 which we studied previously, was much more genotoxic than complex 2b, especially for A549 cells. The plasmid relaxation assay showed that iron(II) complexes do not induce strand breaks in fully paired ds-DNA. The DNA titration experiment showed no intercalation of complex 2b into DNA. Molecular docking revealed however that complexes CpFe(CO)(PPh3) (η1-N-maleimidato) 2a, 2b, 3b and CpFe(CO)(P(OiPr)3)(η1-N-maleimidato) 3c have the greatest potential to bind to mismatched DNA. Our studies demonstrated that the iron(II) complex 1 and 2b are the most interesting compounds in terms of selective cytotoxic action against cancer cells. However, the cellular mechanism of their anticancer activity requires further research.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Complexos de Coordenação , Neoplasias Pulmonares , Fosfinas , Fosfitos , Humanos , Simulação de Acoplamento Molecular , Complexos de Coordenação/química , Ferro , Leucócitos Mononucleares/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , DNA/metabolismo , Maleimidas , Compostos Ferrosos/farmacologia , Antineoplásicos/química , Ligantes , Linhagem Celular Tumoral
19.
PeerJ ; 11: e14939, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36974136

RESUMO

Cardiac magnetic resonance imaging (CMRI) is a non-invasive imaging technique to analyse the structure and function of the heart. It was enhanced considerably over several years to deliver functional information for diagnosing and managing cardiovascular disease. CMRI image delivers non-invasive, clear access to the heart and great vessels. The segmentation of CMRI provides quantification parameters such as myocardial viability, ejection fraction, cardiac chamber volume, and morphological details. In general, experts interpret the CMR images by delineating the images manually. The manual segmentation process is time-consuming, and it has been observed that the final observation varied with the opinion of the different experts. Convolution neural network is a new-age technology that provides impressive results compared to manual ones. In this study convolution neural network model is used for the segmentation task. The neural network parameters have been optimized to perform on the novel data set for accurate predictions. With other parameters, epochs play an essential role in training the network, as the network should not be under-fitted or over-fitted. The relationship between the hyperparameter epoch and accuracy is established in the model. The model delivers the accuracy of 0.88 in terms of the IoU coefficient.


Assuntos
Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação , Coração/diagnóstico por imagem
20.
Int J Biol Macromol ; 246: 125347, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37336371

RESUMO

Wound dressing with poor antibacterial properties, the tendency to adhere to the wound site, poor mechanical strength, and lack of porosity and flexibility are the major cause of blood loss, delayed wound repair, and sometimes causes death during the trauma or injury. In such cases, hydrogel-based antibacterial wound dressing would be a boon to the existing dressing as the moist environment will maintain the cooling temperate and proper exchange of atmosphere around the wound. In the present study, the multifunctional graphene with silver and ε-Poly-l-lysine reinforced into the chitosan matrix (CGAPL) was prepared as a nanobiocomposite wound dressing. The contact angle measurement depicted the hydrophilic property of CGAPL nanobiocomposite dressing (water contact angle 42°), while the mechanical property was 78.9 MPa. The antibacterial and cell infiltration study showed the antimicrobial property of CGAPL nanobiocomposite wound dressing. It also demonstrated no cytotoxicity to the L929 fibroblast cells. Chorioallantoic Membrane (CAM) assay showed the pro-angiogenic potential of CGAPL nanobiocomposite wound dressing. In-vitro scratch wound assay confirmed the migration of cells and increased cell adhesion and proliferation within 18 h of culture on the surface of CGAPL nanobiocomposite dressing. Later, the in-vivo study in the Wistar rat model showed that CGAPL nanobiocomposite dressing significantly enhanced the wound healing process as compared to the commercially available wound dressing Tegaderm (p-value <0.01) and Fibroheal@Ag (p-value <0.005) and obtained complete wound closure in 14 days. Histology study further confirmed the complete healing process, re-epithelization, and thick epidermis tissue formation. The proposed CGAPL nanobiocomposite wound dressing thus offers a novel wound dressing material with an efficient and faster wound healing property.


Assuntos
Quitosana , Grafite , Nanopartículas Metálicas , Ratos , Animais , Quitosana/química , Prata/farmacologia , Prata/química , Nanopartículas Metálicas/química , Peptídeos Antimicrobianos , Ratos Wistar , Bandagens , Antibacterianos/farmacologia , Antibacterianos/química , Hidrogéis
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA