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1.
J Refract Surg ; 37(9): 631-635, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34506235

RESUMO

PURPOSE: To evaluate corneal stiffening in porcine eyes induced by corneal cross-linking (CXL) using riboflavin dissolved in either aqueous dextran or hydroxypropyl methylcellulose (HPMC) solution. METHODS: Fifty-one porcine corneas were divided into three groups of 17 each. After deepithelialization, the first (Dresden) group was treated for 30 minutes with 0.1% riboflavin (riboflavin-5-monophosphate in 0.9% NaCl) dissolved in hypertonic 20% dextran and the second (HPMC) group for 30 minutes with isotonic solution containing 0.1% riboflavin and 1.1% HPMC. Thereafter, corneas of both groups were irradiated using 5.4 J/cm2 (irradiance of 9 mW/cm2 for 10 minutes; 10*9). After CXL, all corneas were kept in an isotonic 16% dextran bath for 2 hours to obtain an equal hydration state. The third group served as the control group. Stress-strain measurements were performed on 5-mm-wide strips. Corneal thickness was monitored throughout the entire course of the experiments. RESULTS: The required stress for a 10% strain was increased by 83% in the Dresden group and 35% in the HPMC group compared to the control group. Resultant Young's modulus (at 10% strain) was 2.53 ± 0.73, 1.87 ± 0.50, and 1.47 ± 0.44 Pa for the Dresden, HPMC, and control groups, respectively. The differences between the Dresden and HPMC groups (P = .006), the Dresden and control groups (P < .001), and the HPMC and control groups (P = .014) were statistically significant. Pachymetry measurements showed a significantly increased corneal thickness after application of HPMC compared with the Dresden group (P = .002) and control group (P = .041). CONCLUSIONS: The biomechanical stiffening of the cornea by CXL can be achieved using dextran- and HPMC-based riboflavin solutions in porcine corneas with an application time of 30 minutes. Dextran-based riboflavin solutions seem to induce a slightly stronger biomechanical response in this setting. HPMC solutions induce less thinning than dextran solutions. [J Refract Surg. 2021;37(9):631-635.].


Assuntos
Substância Própria , Dextranos , Animais , Fenômenos Biomecânicos , Colágeno , Córnea , Reagentes para Ligações Cruzadas , Derivados da Hipromelose , Fármacos Fotossensibilizantes , Riboflavina/farmacologia , Suínos , Raios Ultravioleta
2.
Mater Sci Eng C Mater Biol Appl ; 128: 112293, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474844

RESUMO

Due to increased requirements for precision cancer treatment, cancer chemotherapy and combination therapies have gradually developed in the direction of diagnosis and treatment integration. In this study, a non-toxic nano carrier that demonstrates integrated MRI signal enhancing performance, as well as better chemotherapy and photothermal conversion performance, was prepared and characterized. Furthermore, the carrier was used to construct an integrated system of tumor diagnosis and treatment. Our in vitro studies showed that this system has a considerable inhibition effect on tumor cells during the treatment of chemotherapy when combined with PTT, and in vivo studies showed that the system could improve the MRI signal of the tumor site with application of a safe dosage. Thus, this system based on NGO/USPIO has the potential to be a multi-functional nano drug delivery system integrating diagnosis and treatment benefits and applications that are worthy of further research.


Assuntos
Grafite , Nanopartículas de Magnetita , Neoplasias , Dextranos , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Óxidos
3.
Tumour Biol ; 43(1): 225-247, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34542050

RESUMO

BACKGROUND: The limitations of surgery, radiotherapy, and chemotherapy in cancer treatment and the increase in the application of nanomaterials in the field of biomedicine have promoted the use of nanomaterials in combination with radiotherapy for cancer treatment. OBJECTIVE: To improve the efficiency of cancer treatment, curcumin-naringenin loaded dextran-coated magnetic nanoparticles (CUR-NAR-D-MNPs) were used as chemotherapy and in combination with radiotherapy to verify their effectiveness in treating tumors. METHODS: CUR-NAR-D-MNPs were prepared and studied by several characterization methods. Median inhibitory concentration (IC50) and cellular toxicity were evaluated by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay. The cell death and radiosensitization were studied by acridine orange/ethidium bromide dual staining of MCF-7 human breast cancer cells. RESULTS: CUR-NAR-D-MNPs induce apoptosis and inhibited cell proliferation through reactive oxygen species (ROS) generation. CUR-NAR-D-MNPs used alone had a certain therapeutic effect on tumors. CUR-NAR-D-MNPs plus radiotherapy significantly reduced the tumor volume and led to cell cycle arrest and induction of apoptosis through modulation of P53high, P21high, TNF-αlow, CD44low, and ROShigh signalingCONCLUSIONS:CUR-NAR-D-MNPs are effective in the treatment of tumors when combined with radiotherapy, and show radiosensitization effects against cancer proliferation in vitro and in vivo.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/terapia , Curcumina/química , Flavanonas/química , Nanopartículas de Magnetita/química , Radiossensibilizantes/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quimiorradioterapia , Curcumina/farmacologia , Curcumina/uso terapêutico , Dextranos/química , Feminino , Flavanonas/farmacologia , Flavanonas/uso terapêutico , Humanos , Células MCF-7 , Nanopartículas de Magnetita/uso terapêutico , Camundongos , Radiossensibilizantes/química , Radiossensibilizantes/farmacologia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Molecules ; 26(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34443477

RESUMO

Here, the hierarchical assembly of a collagen mimetic peptide (CMP) displaying four bipyridine moieties is described. The CMP was capable of forming triple helices followed by self-assembly into disks and domes. Treatment of these disks and domes with metal ions such as Fe(II), Cu(II), Zn(II), Co(II), and Ru(III) triggered the formation of microcages, and micron-sized cup-like structures. Mechanistic studies suggest that the formation of the microcages proceeds from the disks and domes in a metal-dependent fashion. Fluorescently-labeled dextrans were encapsulated within the cages and displayed a time-dependent release using thermal conditions.


Assuntos
Materiais Biomiméticos/química , Colágeno/química , Metais/química , Peptídeos/química , Dextranos/química , Íons/química , Ligantes , Estrutura Molecular
5.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34360944

RESUMO

Endothelial and epithelial barrier function is crucial for the maintenance of physiological processes. The barrier paracellular permeability depends on the composition and spatial distribution of the cell-to-cell tight junctions (TJ). Here, we provide an experimental workflow that yields several layers of physiological data in the setting of a single endothelial cell monolayer. Human umbilical vein endothelial cells were grown on Transwell filters. Transendothelial electrical resistance (TER) and 10 kDa FITC dextran flux were measured using Alanyl-Glutamine (AlaGln) as a paracellular barrier modulator. Single monolayers were immunolabelled for Zonula Occludens-1 (ZO-1) and Claudin-5 (CLDN5) and used for automated immunofluorescence imaging. Finally, the same monolayers were used for single molecule localization microscopy (SMLM) of ZO-1 and CLDN5 at the nanoscale for spatial clustering analysis. The TER increased and the paracellular dextran flux decreased after the application of AlaGln and these functional changes of the monolayer were mediated by an increase in the ZO-1 and CLDN5 abundance in the cell-cell interface. At the nanoscale level, the functional and protein abundance data were accompanied by non-random increased clustering of CLDN5. Our experimental workflow provides multiple data from a single monolayer and has wide applicability in the setting of paracellular studies in endothelia and epithelia.


Assuntos
Permeabilidade Capilar , Junções Íntimas/metabolismo , Claudina-5/metabolismo , Dextranos/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Proteína da Zônula de Oclusão-1/metabolismo
6.
Molecules ; 26(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34443384

RESUMO

Sentinel lymph node detection (SLND) is rapidly entering common practice in the management of patients with tumors. The introduction of mannose molecules to 99mTc-labeled dextrans, so far, showed that the sentinel node could trap these agents due to their recognition by the mannose receptors of lymph node macrophages. The current study aimed to synthesize, characterize, and biologically evaluate a series of mannosylated dextran derivatives labeled with 99mTc for potential use in SLND. The compounds were designed to have a dextran with a molecular weight of 10-500 kDa as a backbone, S-derivatized cysteines, efficient SNO chelators, and mannose moieties for binding to mannose receptors. They were successfully synthesized, thoroughly characterized using NMR techniques, and labeled with the fac-[99mTc(CO)3]+ synthon. Labeling with high yields and radiochemical purities was achieved with all derivatives. In vivo biodistribution and imaging studies demonstrated high uptake in the first lymph node and low uptakes in the following node and confirmed the ability to visualize the SLN. Among the compounds studied, 99mTc-D75CM demonstrated the most attractive biological features, and in combination with the high radiochemical yield and stability of the compound, its further evaluation as a new radiopharmaceutical for sentinel lymph node detection was justified.


Assuntos
Dextranos/química , Manose/química , Linfonodo Sentinela/patologia , Tecnécio/química , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Dextranos/síntese química , Imageamento Tridimensional , Injeções Intravenosas , Masculino , Manose/síntese química , Camundongos , Peso Molecular , Radioatividade , Compostos Radiofarmacêuticos/química , Distribuição Tecidual
7.
J Chem Phys ; 155(7): 075101, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34418942

RESUMO

Intercellular fluids in living organisms contain high concentrations of macromolecules such as nucleic acid and protein. Over the past few decades, several studies have examined membraneless organelles in terms of liquid-liquid phase separation. These studies have investigated aggregation/attraction among a rich variety of biomolecules. Here, we studied the association between the polymerization/depolymerization of actin, interconversion between monomeric (G-actin) and filamentous states (F-actin), and water/water phase separation in a binary polymer solution using polyethylene glycol (PEG) and dextran (DEX). We found that actin, which is a representative cytoskeleton, changes its distribution in a PEG/DEX binary solution depending on its polymerization state: monomeric G-actin is distributed homogeneously throughout the solution, whereas polymerized F-actin is localized only within the DEX-rich phase. We extended our study by using fragmin, which is a representative actin-severing and -depolymerizing factor. It took hours to restore a homogeneous actin distribution from localization within the DEX-rich phase, even with the addition of fragmin in an amount that causes complete depolymerization. In contrast, when actin that had been depolymerized by fragmin in advance was added to a solution with microphase-separation, F-actin was found in DEX-rich phase droplets. The micro-droplets tended to deform into a non-spherical morphology under conditions where they contained F-actin. These findings suggest that microphase-separation is associated with the dynamics of polymerization and localization of the actin cytoskeleton. We discuss our observations by taking into consideration the polymer depletion effect.


Assuntos
Actinas/química , Multimerização Proteica , Dextranos/química , Modelos Moleculares , Polietilenoglicóis/química , Estrutura Quaternária de Proteína , Soluções , Água/química
8.
J Pediatr Urol ; 17(4): 589.e1-589.e6, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34364813

RESUMO

INTRODUCTION: Vesicoureteral reflux (VUR) after renal transplant in the pediatric population may be associated with an increased incidence of urinary tract infection (UTIs) leading to increased morbidity, including graft dysfunction and graft loss. The non-orthotopic location of the transplanted ureter, and lack of submucosal tunnel may pose challenges in correcting the VUR using endoscopic injection techniques. Herein we report the results of a systematic review evaluating the outcomes of endoscopic treatment of VUR using Deflux® in this population. METHODS: Pubmed and Embase databases were searched from October 2001 to April 2019. Full-text English articles involving patients less than 18 years old at the time of transplant, with a diagnosis of VUR post-transplantation, who underwent Deflux® treatment were included. Figure 1 outlines our PRISMA-compliant search strategy. RESULTS: We found 6 eligible studies describing Deflux® treatment outcomes in 67 pediatric patients with post-transplant VUR where voiding cystourethrogram (VCUG) confirmed the diagnosis and resolution of VUR. The mean success rate was 36.8%. Ureteral obstruction occurred in 7/67 cases (10.4%). In all these 7 cases of obstruction, ureteric stenting was the initial management, but was only successful in 1 patient. Open ureteroneocystostomy (UNC) was performed in 4/7 cases, while 2/7 were managed expectantly (unknown outcomes). Persistent VUR with UTI despite Deflux® were reported in 20 out of 67 cases. Of these, 7 were managed with prophylactic antibiotics, and 13 with UNC. Success rates were consistently low for UNC after failed Deflux® in comparison to redo UNC in transplant ureters without prior injection. CONCLUSION: Low success rates are seen following injection techniques for VUR after pediatric renal transplant. Although an appealing option, Deflux® may prove counterintuitive due to the high rate of obstruction and suboptimal results if open reimplantation is required. A multi-institutional prospective study with a larger population size may further elucidate these results.


Assuntos
Transplante de Rim , Refluxo Vesicoureteral , Adolescente , Criança , Dextranos , Humanos , Ácido Hialurônico , Transplante de Rim/efeitos adversos , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento , Refluxo Vesicoureteral/etiologia , Refluxo Vesicoureteral/cirurgia
9.
Biomater Sci ; 9(18): 6236-6250, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34365495

RESUMO

A series of modified polysaccharide microparticles have been fabricated and their potential application for scavenging reactive oxygen species (ROS) and their derivatives to achieve osteoarthritis (OA) treatment has been explored. These microparticles were cross-linked dextran (Sephadex) with different carbazate substitution ratios determined by the TNBS assay and elemental analysis. It has been demonstrated that they could effectively scavenge carbonylated proteins and ROS including hydroxyl radicals (˙OH), superoxide anions (˙O2-) and H2O2 and their derivatives with high efficiency, improve the viability of H2O2-treated chondrocytes by reducing their ROS levels, as well as lower their inflammatory factors. The above ability of antioxidation and inflammation resistance improved with the increase of carbazate substitution ratio. Significantly, this work provided the proof that modified Sephadex successfully alleviated the deterioration of cartilage and the progression of OA in vivo. The proposed microparticles showed a very promising capability for reducing ROS levels and further treating OA.


Assuntos
Dextranos , Osteoartrite , Condrócitos , Humanos , Hidrazinas , Peróxido de Hidrogênio , Osteoartrite/tratamento farmacológico , Espécies Reativas de Oxigênio
10.
Nutrients ; 13(7)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34371917

RESUMO

Diabetes mellitus is a chronic condition characterized by increased blood glucose levels from dysfunctional carbohydrate metabolism. Dietary intervention can help to prevent and manage the disease. Food hydrocolloids have been shown to have favorable properties in relation to glycaemic regulation. However, the use of food hydrocolloids of bacterial origin to modulate glucose responses is much less explored than other types of hydrocolloids. We, therefore, carried out the first review examining the impact of intake of food hydrocolloids of bacterial origin (as a direct supplement or incorporated into foods) on glycemic response in humans. Fourteen studies met the inclusion criteria. They used either xanthan gum, pullulan, or dextran as interventions. There was a wide variation in the amount of hydrocolloid supplementation provided and methods of preparation. Postprandial blood glucose responses were reduced in half of the studies, particularly at higher intake levels and longer chain hydrocolloids. When xanthan gum was added to the cooking process of muffins and rice, a significant reduction in postprandial blood glucose was observed. The use of these hydrocolloids is potentially effective though more research is needed in this area.


Assuntos
Bactérias/química , Glicemia/efeitos dos fármacos , Dextranos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucanos/uso terapêutico , Controle Glicêmico , Hipoglicemiantes/uso terapêutico , Polissacarídeos Bacterianos/uso terapêutico , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Glicemia/metabolismo , Coloides , Dextranos/efeitos adversos , Dextranos/isolamento & purificação , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Glucanos/efeitos adversos , Glucanos/isolamento & purificação , Controle Glicêmico/efeitos adversos , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Polissacarídeos Bacterianos/efeitos adversos , Polissacarídeos Bacterianos/isolamento & purificação , Resultado do Tratamento , Adulto Jovem
11.
Georgian Med News ; (315): 185-189, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34365448

RESUMO

The aim of this study was to obtain a more stable and less allergic form of bromelain, an enzyme complex derived from the stem of Pineapple plant (Ananas comosus L. Merr.), via chemical modification with a polysaccharide. In order to obtain purified bromelain (enriched with protein) from comercial bromelain, protein precipitation method by alcohol was used. According to our results the protein concentration after the purification was increased by about 20%. In this work, we examine the method of bromelain's chemical modification with a water-soluble, biocompatible and biodegradable natural polysaccharide - dextran, oxidized to dextran aldehyde. For the determination of the degree of bonding gel-filtration of bromelain and modified bromelain on sephadex G-75 was performed. After gel filtration of bromelain only one fraction-peak was obtained, whereas after gel filtration of modified bromelain with dextran two fraction-peaks were obtained and the degree of protein bonding with dextran was 65±5%. The method was developed both with and without the addition of cysteine. The addition of cysteine increased the activity of modified bromelain from 50±5% to 70±5%. the pH optimum for native bromelain was 7.5, whereas for modified bromelain it was shifted towards 8.5, while the temperature optimum in both cases was 60˚C. Taking into consideration the obtained results and comparing them with literary data we suggest that modified bromelain will have much potential in medical application than currently available native product. Further research is required to test the effect of this modification on bromelain's specific pharmacological and allergic properties.


Assuntos
Ananas , Bromelaínas , Aldeídos , Dextranos
12.
J Chromatogr A ; 1653: 462404, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34348206

RESUMO

Accurate determinations of particle size and particle size distribution (PSD) are essential to achieve the clinical translation of medical nanoparticles (NPs). Herein, dextran-based NPs produced via a water-in-oil emulsification/crosslinking process and developed as nanomedicines were studied. NPs were first characterized using traditional batch-mode techniques as dynamic light scattering (DLS) and laser diffraction. In a second step, their analysis by frit-inlet asymmetrical flow field-flow fractionation (FI-AF4) was explored. The major parameters of the AF4 procedure, namely, crossflow, detector flow, crossflow decay programming and relaxation time were set up. The sizes of the particle fractions eluted under optimized conditions were measured using DLS as an online detector. We demonstrate that FI-AF4 is a powerful method to characterize dextran-NPs in the 200 nm -1 µm range. It provided a more realistic and comprehensive picture of PSD, revealing its heterogenous character and clearly showing the ratio of different populations in the sample, while batch-mode light scattering techniques only detected the biggest particle sizes.


Assuntos
Dextranos , Difusão Dinâmica da Luz , Fracionamento por Campo e Fluxo , Tamanho da Partícula , Dextranos/química
13.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209825

RESUMO

Functional nanocarriers which are able to simultaneously vectorize drugs to the site of interest and exert their own cytotoxic activity represent a significant breakthrough in the search for effective anticancer strategies with fewer side effects than conventional chemotherapeutics. Here, we propose previously developed, self-assembling dextran-curcumin nanoparticles for the treatment of prostate cancer in combination therapy with Doxorubicin (DOXO). Biological effectiveness was investigated by evaluating the cell viability in either cancer and normal cells, reactive oxygen species (ROS) production, apoptotic effect, interference with the cell cycle, and the ability to inhibit cell migration and reverse the epithelial to mesenchymal transition (EMT). The results proved a significant enhancement of curcumin efficiency upon immobilization in nanoparticles: IC50 reduced by a half, induction of apoptotic effect, and improved ROS production (from 67 to 134%) at low concentrations. Nanoparticles guaranteed a pH-dependent DOXO release, with a more efficient release in acidic environments. Finally, a synergistic effect between nanoparticles and Doxorubicin was demonstrated, with the free curcumin showing additive activity. Although in vivo studies are required to support the findings of this study, these preliminary in vitro data can be considered a proof of principle for the design of an effective therapy for prostate cancer treatment.


Assuntos
Curcumina/farmacologia , Dextranos/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias da Próstata/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Curcumina/administração & dosagem , Dextranos/administração & dosagem , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Masculino , Nanopartículas , Células PC-3
14.
Int J Mol Sci ; 22(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208633

RESUMO

The clinical application of human platelet lysate (HPL) holds promise for tissue regeneration, and the development of an efficient vehicle for its delivery is desired. Chitosan-based hydrogels are potential candidates, but they often exhibit weak mechanical properties. In this study, a chitosan/gelatin (CS-GE) hydrogel crosslinked by glyoxal was fabricated for sustained release of HPL. The influence of HPL on Hs68 fibroblast and human umbilical vein endothelial cell (HUVEC) culture was evaluated, and we found that supplementing 5% HPL in the medium could significantly improve cell proliferation relative to supplementing 10% fetal bovine serum (FBS). Moreover, HPL accelerated the in vitro wound closure of Hs68 cells and facilitated the tube formation of HUVECs. Subsequently, we fabricated CS-GE hydrogels crosslinked with different concentrations of glyoxal, and the release pattern of FITC-dextrans (4, 40 and 500 kDa) from the hydrogels was assessed. After an ideal glyoxal concentration was determined, we further characterized the crosslinked CS-GE hydrogels encapsulated with different amounts of HPL. The HPL-incorporated hydrogel was shown to significantly promote the proliferation of Hs68 cells and the migration of HUVECs. Moreover, the release pattern of transforming growth factor-ß1 (TGF-ß1) and platelet-derived growth factor-BB (PDGF-BB) from hydrogel was examined in vitro, demonstrating a sustained release profile of the growth factors. Finally, the chick chorioallantoic membrane assay revealed that HPL encapsulation in the hydrogel significantly stimulated angiogenesis in ovo. These results demonstrate the great potential of the crosslinked CS-GE hydrogel to serve as an effective delivery system for HPL to promote tissue regeneration.


Assuntos
Produtos Biológicos/farmacologia , Plaquetas/metabolismo , Quitosana , Gelatina , Glioxal , Hidrogéis , Regeneração/efeitos dos fármacos , Proliferação de Células , Quitosana/química , Dextranos/química , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Gelatina/química , Glioxal/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Hidrogéis/química , Neovascularização Fisiológica , Porosidade , Cicatrização/efeitos dos fármacos
15.
Molecules ; 26(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34279375

RESUMO

Infection is the major reason that people die from burns; however, traditional medical dressings such as gauze cannot restrain bacterial growth and enhance the healing process. Herein, an organic- and inorganic-base hydrogel with antibacterial activities was designed and prepared to treat burn wounds. Oxidized dextran (ODex) and adipic dihydrazide grafted hyaluronic acid (HA-ADH) were prepared, mixed with quaternized chitosan (HACC) and silver nanoparticles to fabricate Ag@ODex/HA-ADH/HACC hydrogel. The hydrogel, composed of nature biomaterials, has a good cytocompatibility and biodegradability. Moreover, the hydrogel has an excellent antibacterial ability and presents fast healing for burn wounds compared with commercial Ag dressings. The Ag@ODex/HA-ADH/HACC hydrogel will be a promising wound dressing to repair burn wounds and will significantly decrease the possibility of bacterial infection.


Assuntos
Antibacterianos/química , Queimaduras/terapia , Quitosana/análogos & derivados , Hidrogéis/química , Nanopartículas Metálicas/química , Cicatrização , Adipatos/química , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bandagens , Queimaduras/tratamento farmacológico , Linhagem Celular , Dextranos/química , Hidrogéis/farmacologia , Hidrogéis/uso terapêutico , Masculino , Camundongos , Pseudomonas aeruginosa/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Prata/química , Staphylococcus aureus/efeitos dos fármacos
16.
Chem Pharm Bull (Tokyo) ; 69(7): 639-645, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34193712

RESUMO

The purpose of the present study was to evaluate whether iontophoresis (IP) accelerates the intradermal migration rate of medium molecular weight drugs. Sodium polystyrene sulfonate (PSA) and fluorescein isothiocyanate-dextran (FD) were used as model medium molecular weight acidic and non-electrolyte drugs, respectively. Low molecular weight acid and non-electrolyte drugs were also used for comparison. Drug-loaded excised split-layered skin (SL skin) was used in the experiment. SL skin was prepared using (i) whole skin was split once, (ii) the drug solution was applied on the lower skin, and (iii) the upper skin was layered onto the lower skin containing the drug solution as in the original skin. The effect of constant-current cathodal or anodal IP was applied to the SL skin, and the time course of the cumulative amount of drug migration from the SL skin through the dermis to the receiver was followed. In cases without IP and with anodal IP, the intradermal migration rates of medium molecular weight drugs were much lower than those of small molecules. The driving force for drug migration was thought to be simple diffusion through the skin layer. In contrast, cathodal IP significantly increased the intradermal migration rate of PSA not but of FD or low molecular weight drugs. This IP-facilitated migration of PSA was probably due to electrorepulsion. These results suggest that IP can be used to increase the intradermal migration of medium molecular weight charged drugs.


Assuntos
Dextranos/metabolismo , Fluoresceína-5-Isotiocianato/análogos & derivados , Iontoforese/métodos , Poliestirenos/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Dextranos/análise , Fluoresceína-5-Isotiocianato/análise , Fluoresceína-5-Isotiocianato/metabolismo , Fluorometria , Peso Molecular , Poliestirenos/análise , Absorção Cutânea , Suínos
17.
Acta Medica (Hradec Kralove) ; 64(2): 85-90, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34331427

RESUMO

BACKGROUND: Gastrointestinal injury caused by dextran sodium sulphate (DSS) is a reliable porcine experimental model of inflammatory bowel disease (IBD). The purpose of this study was to evaluate the effect of probiotic Lactobacillus casei DN 114001 (LC) on DSS-induced experimental IBD. RESULTS: Eighteen female pigs (Sus scrofa f. domestica, weight 33-36 kg, age 4-5 months) were divided into 3 groups (6 animals per group): controls with no treatment, DSS, and DSS + LC. LC was administered to overnight fasting animals in a dietary bolus in the morning on days 1-7 (4.5 × 1010 live bacteria/day). DSS was applied simultaneously on days 3-7 (0.25 g/kg/day). On day 8, the pigs were sacrificed. Histopathological score and length of crypts/glands (stomach, jejunum, ileum, transverse colon), length and width of villi (jejunum, ileum), and mitotic and apoptotic indices (jejunum, ileum, transverse colon) were assessed. DSS increased the length of glands in the stomach, length of crypts and villi in the jejunum and ileum, and the histopathological score of gastrointestinal damage, length of crypts and mitotic activity in the transverse colon. Other changes did not achieve any statistical significance. Administration of LC reduced the length of villi in the jejunum and ileum to control levels and decreased the length of crypts in the jejunum. CONCLUSIONS: Treatment with a probiotic strain of LC significantly accelerated regeneration of the small intestine in a DSS-induced experimental porcine model of IBD.


Assuntos
Doenças Inflamatórias Intestinais/terapia , Lactobacillus casei , Probióticos/farmacologia , Animais , Dextranos , Modelos Animais de Doenças , Feminino , Doenças Inflamatórias Intestinais/induzido quimicamente , Sulfatos , Suínos
18.
J Pediatr Urol ; 17(4): 547.e1-547.e6, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34274237

RESUMO

BACKGROUND: Endoscopic injection (EI) has been considered a minimally invasive option with high success rates. However, in clinical settings where EI has failed, and after repeat injections or worsening clinical presentation, different treatment modalities may be offered. Open ureteral reimplantation has emerged as a safe option in patients who have failed EI for VUR treatment. Currently there is limited literature describing success of complex robot-assisted laparoscopic ureteral reimplantation (RALUR) following primary EI for vesicoureteral reflux (VUR). OBJECTIVE: We aim to describe our surgical technique and outcomes using RALUR approach following failed EI for VUR. We hypothesize RALUR can be a safe, salvage option in patients who have failed EI for VUR in the setting of recurrent VUR or ureterovesical junction obstruction (UVJO). METHODS: A single site, retrospective study using electronic medical records of all patients who underwent RALUR between 2013 and 2019 following history of previous ipsilateral EI using dextranomer/hyaluronic acid (DHA) for diagnosis of vesicoureteral reflux (VUR) was conducted. Primary outcomes were radiographic resolution and/or clinical resolution. RESULTS: A total of 17 RALUR procedures were reviewed in 16 patients. There were 14 females (87.5%) and 2 males (12.5%). Seven patients had two prior EI. Median (range) age at time of RALUR was 10.1 (5.7-17.9) years, and the average time between EI and RALUR was 5.9 years [1-13]. The average VUR recurrence grade after failed EI was 3 (ranges 2-4) on preoperative VCUG. History of bilateral EI using dextranomer/hyaluronic acid (DHA), was observed in 14 patients. Surgical diagnosis at time of RALUR included persistent VUR (N = 10) or symptomatic ureterovesical junction obstruction (UVJO, N = 6). Mean console times were 102 min (range 70-240 min) for RALUR vs 128 min (range 70-180 min) for cases requiring ureteral tailoring. Six complications occurred in 16 patients (37.6%): Using the Clavien-Dindo classification scale, four patients (25%) were grade I, one (6.3%) grade II, and one (6.3%) was grade IIIb, which required additional procedures for ureteral obstruction. CONCLUSION: RALUR after failed EI should be considered a reasonably safe and effective surgical approach in older children with persistent VUR or acquired UVJO.


Assuntos
Laparoscopia , Procedimentos Cirúrgicos Robóticos , Robótica , Ureter , Refluxo Vesicoureteral , Criança , Dextranos , Feminino , Humanos , Ácido Hialurônico , Masculino , Reimplante , Estudos Retrospectivos , Resultado do Tratamento , Ureter/cirurgia , Refluxo Vesicoureteral/cirurgia
19.
Biol Pharm Bull ; 44(10): 1473-1483, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34305072

RESUMO

The "dextran-magnetic layered double hydroxide-fluorouracil" (DMF) drug delivery system is a new type of pharmaceutic preparation that can cause cancer cell oncosis. In the present study, we used different experimental methods such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), cycle assay, reactive oxygen species (ROS) assay, Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI), Giemsa stainings, transmission electron microscopy, immunofluorescence staining and Western blotting to study the mechanism of expansion death by using Hydroxychloroquine (HCQ) as a positive control and 5-Fluorouracil (5-Fu) as reference. The results showed that DMF exhibited a better anti-tumor effect than 5-Fu in the process of cell death, and the pharmacological mechanism of 5-Fu was changed by its preparation DMF. The mechanism of cancer cell death induced by DMF was similar to that of HCQ. But DMF intervention did not cause a large amount of accumulation of mitochondrial reactive oxygen species, and the location of lysosomotropic LysoTracker Red (LTR) staining induced by DMF was closer to the nucleus or nuclear membrane. Lysosomal membrane permeability (LMP) and its subsequent the explosive death of cancer cells may be mainly related to the direct action of DMF with different organelles.


Assuntos
Antineoplásicos/administração & dosagem , Morte Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Fluoruracila/administração & dosagem , Lisossomos/metabolismo , Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Corantes Azur , Western Blotting , Linhagem Celular Tumoral , Dextranos , Imunofluorescência , Fluoruracila/uso terapêutico , Humanos , Metástase Linfática/tratamento farmacológico , Nanopartículas Magnéticas de Óxido de Ferro , Microscopia Eletrônica de Transmissão , Permeabilidade , Neoplasias Gástricas/tratamento farmacológico
20.
Poult Sci ; 100(7): 101202, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34111612

RESUMO

Fluorescein isothiocyanate-dextran (FITC-d) is being used as an indicator of intestinal paracellular permeability in poultry research. Especially with the industry moving toward antibiotic-free production, intestinal function and integrity issues have been a research focus. An increasing number of scientific conference abstracts and peer-reviewed journal publications have shown that 4-kDa FITC-d is an efficient marker candidate for measurement of intestinal permeability and can be applied in broiler research. However, experimental protocols vary by personnel, instruments used, and research institution, and potential concerns related to this assay have yet to receive the same amount of attention. Understanding protocol consistency within and across laboratories is vital for obtaining accurate, consistent, and comparable experimental results. This review is aimed to 1) summarize different FITC-d assays in broiler research from peer-reviewed publications during the past 6 yr and 2) discuss factors that can potentially affect intestinal permeability results when conducting the FITC-d assay. In summary, it is essential to pay attention to details, including gavage dose, fasting period, sample handling and lab analysis details when conducting the assay in broiler research. Differences in birds (breed/strain, age, and gender) and experimental design (diet, health status/challenge model, and sampling age) need to be considered when comparing serum FITC-d concentration results between different in vivo animal trials.


Assuntos
Galinhas , Dextranos , Animais , Fluoresceína-5-Isotiocianato , Mucosa Intestinal , Intestinos , Permeabilidade
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