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1.
Front Mol Biosci ; 10: 1292509, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965379

RESUMO

Infectious diseases remain among the most pressing concerns for human health. This issue has grown even more complex with the emergence of multidrug-resistant (MDR) bacteria. To address bacterial infections, nanoparticles have emerged as a promising avenue, offering the potential to target bacteria at multiple levels and effectively eliminate them. In this study, silver nanoparticles (AA-AgNPs) were synthesized using the leaf extract of a medicinal plant, Abroma augusta. The synthesis method is straightforward, safe, cost-effective, and environment friendly, utilizing the leaf extract of this Ayurvedic herb. The UV-vis absorbance peak at 424 nm indicated the formation of AA-AgNPs, with the involvement of numerous functional groups in the synthesis and stabilization of the particles. AA-AgNPs exhibited robust antibacterial and antibiofilm activities against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE). The MIC values of AA-AgNPs ranged from 8 to 32 µg/mL. Electron microscopic examination of the interaction of AA-AgNPs with the test bacterial pathogens showed a deleterious impact on bacterial morphology, resulting from membrane rupture and leakage of intracellular components. AA-AgNPs also demonstrated a dose-dependent effect in curtailing biofilm formation below inhibitory doses. Overall, this study highlights the potential of AA-AgNPs in the successful inhibition of both the growth and biofilms of MRSA and VRE bacteria. Following studies on toxicity and dose optimization, such AgNPs could be developed into effective medical remedies against infections.

2.
Sensors (Basel) ; 23(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37447918

RESUMO

Temperature sensors, such as Fiber Bragg Grating (FBG) and thermocouple (TC), have been widely used for monitoring the interstitial tissue temperature during laser irradiation. The aim of the current study was to compare the performance of both FBG and TC in real-time temperature monitoring during endoscopic and circumferential laser treatment on tubular tissue structure. A 600-µm core-diameter diffusing applicator was employed to deliver 980-nm laser light (30 W for 90 s) circumferentially for quantitative evaluation. The tip of the TC was covered with a white tube (W-TC) in order to prevent direct light absorption and to minimize temperature overestimation. The temperature measurements in air demonstrated that the measurement difference in the temperature elevations was around 3.5 °C between FBG and W-TC. Ex vivo porcine liver tests confirmed that the measurement difference became lower (less than 1 °C). Ex vivo porcine esophageal tissue using a balloon-integrated catheter exhibited that both FBG and W-TC consistently showed a comparable trend of temperature measurements during laser irradiation (~2 °C). The current study demonstrated that the white tube-covered TC could be a feasible sensor to monitor interstitial tissue temperature with minimal overestimation during endoscopic laser irradiation. Further in vivo studies on gastroesophageal reflux disease will investigate the performance of the W-TC to monitor the temperature of the esophageal mucosa surface in real-time mode to warrant the safety of endoscopic laser treatment.


Assuntos
Hipertermia Induzida , Suínos , Animais , Temperatura , Lasers , Luz , Fibras Ópticas
3.
Biomed Res Int ; 2022: 4400276, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252445

RESUMO

The popularity of light/energy devices for cosmetic purposes (e.g., skin care) is increasing. However, the effects and underlying mechanisms remain poorly understood. Commencing in the 1960s, various studies have evaluated the beneficial effects of a light source on cells and tissues. The techniques evaluated include low-level light (laser) therapy and photobiomodulation (PBM). Most studies on PBM used red light sources, but, recently, many studies have employed near-infrared light sources including those of wavelength 800 nm. Here, we used a light-emitting diode (LED) array with a wavelength of 863 nm to treat DMBA/TPA-induced mouse skin tumors; treatment with the array delayed tumor development and reduced the levels of systemic inflammatory cytokines. These results suggest that light therapy could be beneficial. However, the effects were small. Further studies on different skin tumors using an optimized LED setup are required. Combination therapies (conventional methods and an LED array) may be useful.


Assuntos
Terapia com Luz de Baixa Intensidade , Neoplasias Cutâneas , Animais , Citocinas , Raios Infravermelhos , Terapia com Luz de Baixa Intensidade/métodos , Camundongos , Camundongos Endogâmicos ICR , Neoplasias Cutâneas/induzido quimicamente
4.
Int J Mol Sci ; 19(4)2018 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-29652833

RESUMO

To prolong blood circulation and avoid the triggering of immune responses, nanoparticles in the bloodstream require conjugation with polyethylene glycol (PEG). However, PEGylation hinders the interaction between the nanoparticles and the tumor cells and therefore limits the applications of PEGylated nanoparticles for therapeutic drug delivery. To overcome this limitation, zwitterionic materials can be used to enhance the systemic blood circulation and tumor-specific delivery of hydrophobic agents such as IR-780 iodide dye for photothermal therapy. Herein, we developed micellar nanoparticles using the amphiphilic homopolymer poly(12-(methacryloyloxy)dodecyl phosphorylcholine) (PCB-lipid) synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. The PCB-lipid can self-assemble into micelles and encapsulate IR-780 dye (PCB-lipid-IR-780). Our results demonstrated that PCB-lipid-IR-780 nanoparticle (NP) exhibited low cytotoxicity and remarkable photothermal cytotoxicity to cervical cancer cells (TC-1) upon near-infrared (NIR) laser irradiation. The biodistribution of PCB-lipid-IR-780 showed higher accumulation of PCB-lipid-IR-780 than that of free IR-780 in the TC-1 tumor. Furthermore, following NIR laser irradiation of the tumor region, the PCB-lipid-IR-780 accumulated in the tumor facilitated enhanced tumor ablation and subsequent tumor regression in the TC-1 xenograft model. Hence, these zwitterionic polymer-lipid hybrid micellar nanoparticles show great potential for cancer theranostics and might be beneficial for clinical applications.


Assuntos
Hipertermia Induzida/métodos , Indóis/química , Fototerapia/métodos , Polímeros/síntese química , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/terapia , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Micelas , Nanopartículas/administração & dosagem , Nanopartículas/química , Polímeros/química , Polímeros/farmacocinética , Distribuição Tecidual , Resultado do Tratamento , Neoplasias do Colo do Útero/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Mol Imaging Biol ; 20(4): 533-543, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29450802

RESUMO

PURPOSE: Paclitaxel (PTX) loaded hydrophobically modified glycol chitosan (HGC) micelle is biocompatible in nature, but it requires cancer targeting ability and stimuli release property for better efficiency. To improve tumor retention and drug release characteristic of HGC-PTX nanomicelles, we conjugated cancer targeting heptamethine dye, MHI-148, which acts as an optical imaging agent, targeting moiety and also trigger on-demand drug release on application of NIR 808 nm laser. PROCEDURES: The amine group of glycol chitosan modified with hydrophobic 5ß-cholanic acid and the carboxyl group of MHI-148 were bonded by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxysuccinimide chemistry. Paclitaxel was loaded to MHI-HGC nanomicelle by an oil-in-water emulsion method, thereby forming MHI-HGC-PTX. RESULTS: Comparison of near infrared (NIR) dyes, MHI-148, and Flamma-774 conjugated to HGC showed higher accumulation for MHI-HGC in 4T1 tumor and 4T1 tumor spheroid. In vitro studies showed high accumulation of MHI-HGC-PTX in 4T1 and SCC7 cancer cell lines compared to NIH3T3 cell line. In vivo fluorescence imaging of the 4T1 and SCC7 tumor showed peak accumulation of MHI-HGC-PTX at day 1 and elimination from the body at day 6. MHI-HGC-PTX showed good photothermal heating ability (50.3 °C), even at a low concentration of 33 µg/ml in 1 W/cm2 808 nm laser at 1 min time point. Tumor reduction studies in BALB/c nude mice with SCC7 tumor showed marked reduction in MHI-HGC-PTX in the PTT group combined with photothermal therapy compared to MHI-HGC-PTX in the group without PTT. CONCLUSION: MHI-HGC-PTX is a cancer theranostic agent with cancer targeting and optical imaging capability. Our studies also showed that it has cancer targeting property independent of tumor type and tumor reduction property by combined photothermal and chemotherapeutic effects.


Assuntos
Carbocianinas/química , Quitosana/química , Corantes/química , Luz , Micelas , Nanopartículas/química , Neoplasias/terapia , Nanomedicina Teranóstica , Animais , Linhagem Celular , Cumarínicos/química , Humanos , Hipertermia Induzida , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/ultraestrutura , Neoplasias/patologia , Paclitaxel/farmacologia , Fototerapia , Espectroscopia de Luz Próxima ao Infravermelho , Tiazóis/química , Distribuição Tecidual
6.
Carbohydr Polym ; 181: 1-9, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29253923

RESUMO

In this study, we propose using IR 780-loaded, CD44-targeted hyaluronic acid-based micelles (HA-IR 780) for enhanced photothermal therapy (PTT) effects in tumors. Two kinds of HA-C18 micelles were synthesized from different C18 feed ratios with degree of substitution of 3% and 13% respectively. Three different IR 780 weight percentages were used for micelle formation with loading content of 4.6%, 7.9%, and 10.3% respectively. The IC50 value of HA-IR 780 in TC1 cells was 21.89µgmL-1 (32.81µM). Upon irradiation of the tumor site with an 808-nm laser (2Wcm-2) for 2min, the temperature in the tumor in the HA-IR 780-treated groups reached 49.9°C which exceeds the temperature threshold to induce irreversible tissue damage. Toxicity studies showed that HA-IR 780 does not cause any adverse effects in organs, including heart, liver, lungs, kidney and spleen, although it selectively caused cell damage in the tumor region upon laser irradiation. Therefore, the present study suggests that HA-IR 780 can cause selective cell death in tumor regions due to its enhanced tumor-targeting and photothermal capabilities.


Assuntos
Ácido Hialurônico/química , Hipertermia Induzida , Indóis/uso terapêutico , Micelas , Neoplasias/tratamento farmacológico , Fototerapia , Animais , Sobrevivência Celular/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Receptores de Hialuronatos/metabolismo , Indóis/farmacologia , Camundongos Endogâmicos C57BL , Neoplasias/patologia , Distribuição Tecidual/efeitos dos fármacos
7.
Sci Rep ; 7(1): 2108, 2017 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-28522841

RESUMO

Near-infrared fluorescent (NIRF) imaging modality holds great promise for tumor detection and offers several advantages of bioimaging, such as high tissue penetration with less background scattering. The disadvantage of NIRF bioimaging is that it has very low spatial resolution. Thus, the combination of NIRF with magnetic resonance imaging (MRI) is a good option because MRI can provide anatomical information with a higher resolution. Heptamethine cyanine dye (MHI-148) has been reported to have tumor-targeting capability which was used here as the NIRF agent. DSPE-SPION nanoparticles were synthesized by the solvent hydration method and conjugated with MHI-148 dye to form a MRI/NIRF dual imaging probe. The size and charge of the MHI-DSPE-SPION were found to be about 84 ± 6 nm and 3.7 mV by DLS & Zeta Potential analysis. In vivo MRI of the SCC7 tumor showed an enhanced accumulation of MHI-DSPE-SPION, peaking at day 1, compared to 4 hrs with the control DSPE-SPION. An in vivo photothermal tumor reduction study was done on the SCC7 tumor of BALB/c nude mice. Tumor reduction study showed complete tumor removal after 8 days. In conclusion, MHI-DSPE-SPION can be used as a cancer theranostics material because it provides MRI-optical imaging capabilities and the photothermal therapy (PTT) effect.


Assuntos
Carbocianinas/química , Hipertermia Induzida/métodos , Nanopartículas Metálicas/uso terapêutico , Imagem Multimodal/métodos , Neoplasias Experimentais/terapia , Fototerapia/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Células 3T3 , Animais , Linhagem Celular Tumoral , Compostos Férricos/química , Corantes Fluorescentes/química , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Nanopartículas Metálicas/química , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/diagnóstico por imagem
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