Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 81
Filtrar
1.
Biomed Res Int ; 2022: 9863616, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35299896

RESUMO

Copper oxide (CuO) nanoparticle- (NP-) decorated carbon NPs (CNPs) were produced as colloidal suspension through pulsed laser ablation technique in liquid (PLAL) medium. The antimicrobial activity of the produced NPs was tested against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), and anticancer activity was tested against breast cancer cell line, MCF-7, together with the biocompatibility assessment of these NPs. The X-ray diffraction (XRD) patterns of the obtained CNPs showed peaks at 26.58° and 43.78° (2θ) identical to (002) and (111) planes, respectively, of the carbon phases. It also displayed new peaks at 38.5° and 48.64° (2θ) after doping with CuO NPs. Transmission electron microscope (TEM) images revealed the crystalline nature with the spherical shape of the prepared CNPs with 5-40 nm diameter ranges. In addition, the NP effects on the bacterial cell walls and nucleic acid were confirmed using a scanning electron microscope (SEM) and microscopic fluorescence analysis. The NPs showed antibacterial activity through SEM examinations against the pathogenic microbial species, S. aureus and E. coli. In the cellular material release assay, the optical density of the bacterial cells, treated with NPs, displayed a significant increase with the time of exposure to NPs, and the cytotoxicity reached more than 80% of the level for the CNPs decorated with CuO NPs. The morphology of the MCF-7 cells treated with NPs decreased numbers, and the loss of contact with the surrounding cells was observed. These results confirmed that the CNPs decorated with CuO NPs have no observable side effects and can be safely used for therapeutic applications. It is also noteworthy that it is the first report of preparation of CuO NPs decorated with CNPs (CuO NPs-CNPs) by PLAL, and the produced NPs showed antimicrobial antiproliferative activities against breast cancer cell lines, MCF-7. The main advantage of the PLAL technique of synthesizing CuO NPs-CNPs provided a two-step, cost-effective, and eco-friendly method.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Carbono/química , Carbono/farmacologia , Cobre/química , Cobre/farmacologia , Nanopartículas Metálicas/química , Coloides/química , Coloides/farmacologia , Escherichia coli/efeitos dos fármacos , Feminino , Humanos , Terapia a Laser , Células MCF-7 , Staphylococcus aureus/efeitos dos fármacos
2.
Molecules ; 27(2)2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35056860

RESUMO

A ferrofluid with 1,2-Benzenediol-coated iron oxide nanoparticles was synthesized and physicochemically analyzed. This colloidal system was prepared following the typical co-precipitation method, and superparamagnetic nanoparticles of 13.5 nm average diameter, 34 emu/g of magnetic saturation, and 285 K of blocking temperature were obtained. Additionally, the zeta potential showed a suitable colloidal stability for cancer therapy assays and the magneto-calorimetric trails determined a high power absorption density. In addition, the oxidative capability of the ferrofluid was corroborated by performing the Fenton reaction with methylene blue (MB) dissolved in water, where the ferrofluid was suitable for producing reactive oxygen species (ROS), and surprisingly a strong degradation of MB was also observed when it was combined with H2O2. The intracellular ROS production was qualitatively corroborated using the HT-29 human cell line, by detecting the fluorescent rise induced in 2,7-dichlorofluorescein diacetate. In other experiments, cell metabolic activity was measured, and no toxicity was observed, even with concentrations of up to 4 mg/mL of magnetic nanoparticles (MNPs). When the cells were treated with magnetic hyperthermia, 80% of cells were dead at 43 °C using 3 mg/mL of MNPs and applying a magnetic field of 530 kHz with 20 kA/m amplitude.


Assuntos
Coloides/química , Coloides/farmacologia , Hipertermia Induzida/métodos , Nanopartículas Magnéticas de Óxido de Ferro/química , Espécies Reativas de Oxigênio/metabolismo , Catecóis/química , Linhagem Celular , Coloides/síntese química , Citotoxinas/síntese química , Citotoxinas/química , Citotoxinas/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Magnetismo , Microscopia Eletrônica de Transmissão , Oxidantes/síntese química , Oxidantes/química , Oxidantes/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X
3.
ACS Appl Mater Interfaces ; 13(5): 5989-5998, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33522791

RESUMO

Liquid-in-liquid emulsions are kinetically stable colloids that undergo liquid-to-gas phase transitions in response to thermal or acoustic stimuli. Perfluorocarbons (PFCs) are preferred species as their highly fluorinated nature imparts unique properties that are unparalleled by nonfluorinated counterparts. However, traditional methods to prepare PFC emulsions lack the ability to precisely tune the thermodynamic stability of the fluorous-water interphase and consequently control their vaporization behavior. Here, we report a privileged fluoroalkanoic acid that undergoes concentration-dependent assembly on the surfaces of fluorous droplets to modulate interfacial tension. This allows for the rational formulation of orthogonal PFC droplets that can be programmed to vaporize at specified ultrasound powers. We exploit this behavior in two exemplary biomedical settings by developing emulsions that aid ultrasound-mediated hemostasis and enable bioorthogonal delivery of molecular sensors to mammalian cells. Mechanistic insights gained from these studies can be generalized to tune the thermodynamic interfacial equilibria of PFC emulsions toward designing controllable tools for precision medicine.


Assuntos
Materiais Biocompatíveis/química , Fluorocarbonos/química , Células A549 , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Coloides/química , Coloides/farmacologia , Fluorocarbonos/farmacologia , Humanos , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície , Termodinâmica , Células Tumorais Cultivadas , Ondas Ultrassônicas , Água/química
4.
Hum Cell ; 34(2): 436-444, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33387361

RESUMO

Carcinostatic effects of combined use of ascorbic acid (Asc), 2-O-phospho- or 6-O-palmitoyl ascorbate (Asc2Phos, Asc6Palm) or diverse alkanoyl Asc, and nano-sized platinum-poly(N-vinyl-pyrrolidone) colloid (PVP-Pt; 2-nm diameter) were examined on human esophagus carcinoma-derived cells KYSE70. Cell viability was repressed by 'Asc6Palm + PVP-Pt' mixture more markedly than by Asc6Palm or PVP-Pt alone, together with cell shrinkage and fragmentation, in contrast to no additive carcinostatic effect of 'Asc + PVP-Pt' or 'Asc2Phos + PVP-Pt'. The effects might be partly due to efficiency for intracellular uptake of PVP-Pt, as previously shown by our studies that Pt atoms composed of PVP-Pt were incorporated into human tongue carcinoma cells by 9.6-fold compared to normal human tongue epitheliocytes. Asc6Palm was advantageous for intracellular uptake, in terms of the proper balance for molecular hydrophilicity-lipophilicity (BMHL), whereas 6-O-stearoyl (C18) Asc or 2,6-O-dipalmitoyl (2 × C16) was demonstrated to be less carcinostatic owing to a lower BMHL. Although esterolytically converted from Asc6Palm, Asc was necessitated to be retained for efficient carcinostasis, and demonstrated by HPLC-coulometric ECD analysis to be appreciably stabilized in electrolytically generated hydrogen (dissolved hydrogen: 0.575 mg/L)-water, but scarcely in hydrogen-gas-bubbled water (0.427 mg/L), Mg stick-derived hydrogen (0.044 mg/L) water, or tap water, suggesting that hydrogen-rich water suppresses oxidative decomposition of Asc. Thus, Asc6Palm plus PVP-Pt with hydrogen-rich water supplement might be applicable for carcinostatic therapy.


Assuntos
Antineoplásicos/farmacologia , Ácido Ascórbico/farmacologia , Carcinoma de Células Escamosas/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Coloides/farmacologia , Neoplasias Esofágicas/patologia , Hidrogênio/farmacologia , Nanocompostos , Antineoplásicos/uso terapêutico , Ácido Ascórbico/química , Ácido Ascórbico/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Linhagem Celular Tumoral , Coloides/química , Coloides/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Humanos , Hidrogênio/uso terapêutico , Platina/farmacologia , Água
5.
Int J Nanomedicine ; 15: 7415-7431, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116479

RESUMO

INTRODUCTION: AT101, the R-(-)-enantiomer of the cottonseed-derived polyphenol gossypol, is a promising drug in glioblastoma multiforme (GBM) therapy due to its ability to trigger autophagic cell death but also to facilitate apoptosis in tumor cells. It does have some limitations such as poor solubility in water-based media and consequent low bioavailability, which affect its response rate during treatment. To overcome this drawback and to improve the anti-cancer potential of AT101, the use of cubosome-based formulation for AT101 drug delivery has been proposed. This is the first report on the use of cubosomes as AT101 drug carriers in GBM cells. MATERIALS AND METHODS: Cubosomes loaded with AT101 were prepared from glyceryl monooleate (GMO) and the surfactant Pluronic F-127 using the top-down approach. The drug was introduced into the lipid prior to dispersion. Prepared formulations were then subjected to complex physicochemical and biological characterization. RESULTS: Formulations of AT101-loaded cubosomes were highly stable colloids with a high drug entrapment efficiency (97.7%) and a continuous, sustained drug release approaching 35% over 72 h. Using selective and sensitive NMR diffusometry, the drug was shown to be efficiently bound to the lipid-based cubosomes. In vitro imaging studies showed the high efficiency of cubosomal nanoparticles uptake into GBM cells, as well as their marked ability to penetrate into tumor spheroids. Treatment of GBM cells with the AT101-loaded cubosomes, but not with the free drug, induced cytoskeletal rearrangement and shortening of actin fibers. The prepared nanoparticles revealed stronger in vitro cytotoxic effects against GBM cells (A172 and LN229 cell lines), than against normal brain cells (SVGA and HMC3 cell lines). CONCLUSION: The results indicate that GMO-AT101 cubosome formulations are a promising basic tool for alternative approaches to GBM treatment.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Portadores de Fármacos/química , Glioblastoma/tratamento farmacológico , Gossipol/análogos & derivados , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Disponibilidade Biológica , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Coloides/química , Coloides/farmacologia , Citoesqueleto/efeitos dos fármacos , Preparações de Ação Retardada/química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Glioblastoma/patologia , Glicerídeos/química , Gossipol/administração & dosagem , Gossipol/farmacocinética , Gossipol/farmacologia , Humanos , Lipídeos/química , Espectroscopia de Ressonância Magnética/métodos , Nanopartículas/administração & dosagem , Nanopartículas/química , Poloxâmero/química , Solubilidade
6.
Photochem Photobiol Sci ; 19(8): 1088-1098, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32638825

RESUMO

Curcumin-based novel colloidal nanocapsules were prepared from amphiphilic poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (F108). These colloidal nanocapsules appeared as spherical particles with size ranging between 270 and 310 nm. Curcumin fluorescence spectra exhibited an aggregation-induced 23 nm red-shift of the emission maximum in addition to the enhancement of the fluorescence quantum yield in these nanocapsules. The cytotoxicity of curcumin and colloidal nanocapsules was assessed using human derived immortalized cell lines (A549 and A375 cells) in the presence and absence of light irradiation. The nanocapsules exhibited a >30-fold decrease in IC50, suggesting enhanced anticancer activity associated with curcumin encapsulation. Higher toxicity was also reported in the presence of light irradiation (as shown by the IC50 data), indicating their potential for future application in photodynamic therapy. Finally, A375 cells treated with curcumin and the nanocapsules showed a significant increase in single- and/or double-strand DNA breaks upon exposure to light, indicating promising biological effects.


Assuntos
Antineoplásicos/farmacologia , Curcumina/farmacologia , Nanocápsulas/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Polietilenoglicóis/farmacologia , Propilenoglicóis/farmacologia , Tensoativos/farmacologia , Células A549 , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Coloides/síntese química , Coloides/química , Coloides/farmacologia , Curcumina/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Polietilenoglicóis/química , Propilenoglicóis/química , Relação Estrutura-Atividade , Tensoativos/química
7.
Reprod Domest Anim ; 55(9): 1154-1162, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32594592

RESUMO

The objective of this study was to design a protocol to separate spermatozoa from seminal plasma of raw llama semen without prior enzymatic treatment using a single-layer centrifugation with Androcoll-E™ (AE). Two experiments were performed: (a) samples were divided into three aliquots (1 ml) that were deposited on the top of 4, 5 or 6 ml of AE and were centrifuged at 800g for 20 min and (b) samples were divided into two aliquots (1 ml) that were deposited on the top of 4 ml of AE and were centrifuged at 600g or 1,000g for 20 min. Columns of 5 and 6 ml of AE showed a total sperm motility (TM) significantly lower, while in the 4 ml column, this parameter was not different from the TM of samples before the AE treatment. The percentage of spermatozoa with intact and functional membranes, normal morphology and intact acrosomes, as well as the percentages of sperm with highly condensed chromatin, was conserved (p Ëƒ .05) in the three column heights and in the two centrifugation speeds evaluated. In conclusion, the different column heights of AE (4, 5 and 6 ml) and the different centrifugation speeds used (600, 800 and 1,000g) allow separating spermatozoa of raw llama semen without enzymatic treatment, preserving the evaluated sperm characteristics. However, of all the studied treatments, centrifugation in the 4 ml column of AE at 800g would be the method of choice to process raw llama semen samples destined for reproductive biotechnologies.


Assuntos
Camelídeos Americanos/fisiologia , Coloides/farmacologia , Espermatozoides/fisiologia , Acrossomo , Animais , Sobrevivência Celular , Centrifugação/métodos , Centrifugação/veterinária , Masculino , Análise do Sêmen/veterinária , Motilidade dos Espermatozoides
8.
Curr Top Med Chem ; 20(4): 280-292, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31976835

RESUMO

BACKGROUND: The biodegradable and biocompatible nature of pectin-based films is of particular interest in wound dressing applications, due to its non-toxicity, pH-sensitivity and gelling activity. An approach to improve the mechanical properties, the release profile of bioactive compounds as well as the performance in wet environments of pectin-based films is mixing with other biopolymers. OBJECTIVE: To prepare hydrocolloid films based on crosslinked pectin / starch blend loaded with bioactive extracts from leaves of G. tinctoria and U. molinae with controlled release of bioactive compounds and healing property. METHODS: The hydrocolloid films were characterized by FTIR, SEM, and TGA-FTIR techniques and their tensile properties, water uptake, and polyphenolic release profile in aqueous media were evaluated. The dermal anti inflammatory activity of the hydrocolloid films was assessed by the mouse ear inflammation test. The wound healing property of the loaded hydrocolloid films was explored in a rat model and in a clinical trial (sacrum pressure ulcer). RESULTS: The films showed an adequate water-uptake capacity between 100-160%. The release of active compounds from the hydrocolloid films followed the Korsmeyer-Peppas equation. The mechanical properties of hydrocolloid films were not affected by the plant extracts within the concentration range used. The incorporation of the bioactive extracts in the polysaccharide films inhibited the topical edematous response by about 50%. The topical application of the loaded hydrocolloid film on the pressure ulcer is completely closed after 17 days without showing any adverse reaction. CONCLUSION: A novel hydrocolloid matrix was produced from crosslinked starch-pectin, which exhibited suitable chemical-physical properties to be used as a carrier of plant extracts with wound healing properties.


Assuntos
Anti-Inflamatórios/farmacologia , Reagentes de Ligações Cruzadas/farmacologia , Pectinas/farmacologia , Extratos Vegetais/farmacologia , Úlcera por Pressão/tratamento farmacológico , Amido/farmacologia , Cicatrização/efeitos dos fármacos , Idoso , Animais , Anti-Inflamatórios/química , Bandagens , Coloides/química , Coloides/farmacologia , Reagentes de Ligações Cruzadas/química , Feminino , Humanos , Magnoliopsida/química , Masculino , Camundongos , Camundongos Endogâmicos , Myrtaceae/química , Pectinas/química , Extratos Vegetais/química , Folhas de Planta/química , Úlcera por Pressão/patologia , Ratos , Ratos Sprague-Dawley , Amido/química
9.
Microb Cell Fact ; 18(1): 210, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796078

RESUMO

BACKGROUND: Synthesis of nanoparticles (NPs) and their incorporation in materials are amongst the most studied topics in chemistry, physics and material science. Gold NPs have applications in medicine due to their antibacterial and anticancer activities, in biomedical imaging and diagnostic test. Despite chemical synthesis of NPs are well characterized and controlled, they rely on the utilization of harsh chemical conditions and organic solvent and generate toxic residues. Therefore, greener and more sustainable alternative methods for NPs synthesis have been developed recently. These methods use microorganisms, mainly yeast or yeast cell extract. NPs synthesis with culture supernatants are most of the time the preferred method since it facilitates the purification scheme for the recovery of the NPs. Extraction of NPs, formed within the cells or cell-wall, is laborious, time-consuming and are not cost effective. The bioactivities of NPs, namely antimicrobial and anticancer, are known to be related to NPs shape, size and size distribution. RESULTS: Herein, we reported on the green synthesis of gold nanoparticles (AuNPs) mediated by pyomelanin purified from the yeast Yarrowia lipolytica. A three levels four factorial Box-Behnken Design (BBD) was used to evaluate the influence of temperature, pH, gold salt and pyomelanin concentration on the nanoparticle size distribution. Based on the BBD, a quadratic model was established and was applied to predict the experimental parameters that yield to AuNPs with specific size. The synthesized nanoparticles with median size value of 104 nm were of nanocrystalline structure, mostly polygonal or spherical. They exhibited a high colloidal stability with zeta potential of - 28.96 mV and a moderate polydispersity index of 0.267. The absence of cytotoxicity of the AuNPs was investigated on two mammalian cell lines, namely mouse fibroblasts (NIH3T3) and human osteosarcoma cells (U2OS). Cell viability was only reduced at AuNPs concentration higher than 160 µg/mL. Moreover, they did not affect on the cell morphology. CONCLUSION: Our results indicate that different process parameters affect significantly nanoparticles size however with the mathematical model it is possible to define the size of AuNPs. Moreover, this melanin-based gold nanoparticles showed neither cytotoxicity effect nor altered cell morphology.


Assuntos
Ouro/metabolismo , Melaninas/metabolismo , Nanopartículas Metálicas/química , Yarrowia/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Coloides/química , Coloides/farmacologia , Ouro/química , Ouro/farmacologia , Humanos , Melaninas/biossíntese , Melaninas/isolamento & purificação , Camundongos , Células NIH 3T3 , Propriedades de Superfície , Yarrowia/citologia , Yarrowia/crescimento & desenvolvimento
10.
Colloids Surf B Biointerfaces ; 181: 39-47, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31121380

RESUMO

Understanding the difference in physicochemical properties and biological response between colloidal and powder formulations of identical materials is important before the given materials are used in a medical milieu. In this study we compared a set of biological effects of colloidal and powder formulations of composite nanoparticles comprising superparamagnetic iron oxide cores and silicate/carbon shells. Magnetic dipole interaction between adjacent nanoparticles was more pronounced in their powders than in their colloidal formulations. Nanoparticles delivered as powders were thus more responsive to the magnetic field, but exhibited reduced uptake in bone and brain cancer cells, including K7M2 osteosarcoma line and U87 and E297 glioblastoma lines. Specifically, while the alternate magnetic field elicited a more rapid heat generation in cell culture media supplemented with the magnetic powders, the nanoparticles dispersed in the same media were uptaken by the cancer cells more copiously. The cellular uptake proved to be more crucial in defining the effect on cell survival, given that suspended formulations elicited a greater degree of cancer cell death in the magnetic field compared to the powder-containing formulations. Because of this effect, colloidal formulations were able to target cancer cells more effectively than the powders: they reduced the viability of all three tested cancer cell lines to a significantly greater degree that the viability of the normal, MDCK-MDR1 cell line. It is concluded that better uptake profile can make up for the lower heating rate in the AC field and lead to a more effective magnetic hyperthermia therapy. These results also demonstrate that the direct delivery of ferrofluids is more optimal than the administration of their constitutive particles as powders.


Assuntos
Coloides/farmacologia , Nanopartículas/química , Pós/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Coloides/síntese química , Coloides/química , Cães , Composição de Medicamentos , Citometria de Fluxo , Células Madin Darby de Rim Canino/efeitos dos fármacos , Tamanho da Partícula , Pós/síntese química , Pós/química , Propriedades de Superfície
11.
Colloids Surf B Biointerfaces ; 177: 346-355, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30772669

RESUMO

With an excellent near-infrared (NIR) light-responsive property, polypyrrole (PPy) nanoparticle has emerged as a promising NIR photothermal transducing agent for tumor photothermal therapy (PTT). Herein, we reported the PVP mediated one-pot synthesis of colloidal stable and biocompatible PPy nanoparticles (PPy-PVP NPs) for combined tumor photothermal-chemotherapy. The influence of molecular weight and PVP concentration on the spectroscopic characteristic, photothermal feature, drug loading performance, and antitumor efficiency of the resultant PPy-PVP NPs was systematically studied. By choosing PVP with a molecular weight of 360 kDa (concentration of 5 mg/mL) as the template and surface modifier during the synthesis, PPy-PVP NPs with optimal spectroscopic characteristic, photothermal feature, drug loading performance, and antitumor efficiency were synthesized. Findings in this study are anticipated to provide an in-depth understanding of the important character of surface engineering in the rational design and biomedical applications of PPy NPs.


Assuntos
Antineoplásicos/farmacologia , Materiais Biocompatíveis/farmacologia , Nanopartículas/química , Fototerapia , Polímeros/farmacologia , Pirróis/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Coloides/química , Coloides/farmacologia , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Raios Infravermelhos , Camundongos , Camundongos Endogâmicos , Tamanho da Partícula , Polímeros/síntese química , Polímeros/química , Pirróis/síntese química , Pirróis/química , Propriedades de Superfície , Células Tumorais Cultivadas
12.
Perfusion ; 34(2): 130-135, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30114960

RESUMO

INTRODUCTION: In the literature addressing cardiopulmonary bypass (CPB) prime composition, there is a considerable lack of discussion concerning plasma osmolality changes induced by using a hyperosmolar prime. With this study, we try to determine the magnitude and temporal relationship of plasma osmolality changes related to the use of a hyperosmolar CPB prime. METHOD: In this prospective observational study performed in a university hospital setting, we enrolled thirty patients scheduled for elective coronary bypass surgery. Plasma osmolality was analysed on eight occasions. A hyperosmolar CPB prime was used. RESULTS: Analyses of the perioperative plasma osmolality on eight occasions gave the following results: the preoperative osmolality level was normal (297±4 mOsm/kg); a significant increase to 322±17 mOsm/kg (p<0.001) was observed at the commencement of CPB and remained elevated after 30 minutes (310±4 mOsm/kg) and throughout the procedure (309±4 mOsm/kg); the osmolality level returned to 291±5 mOsm/kg on day 1 postoperatively and remained normal the following day (291±6 mOsm/kg). CONCLUSIONS: Use of hyperosmolar CPB prime resulted in a dramatic and instant elevation of the plasma osmolality. Rapid changes in plasma osmolality are associated with organ dysfunction (e.g. osmotic demyelination syndrome), therefore, effects on plasma osmolality related to the CPB prime composition should be recognised. Influence on organ function and clinical outcome warrants further investigations. - Clinical Trials.gov (NCT03060824). Changes in Plasma Osmolality Related to the Use of Cardiopulmonary Bypass With Hyperosmolar Prime. URL: https://clinicaltrials.gov/ct2/show/NCT03060824?term=cpb&cond=osmolality&rank=1.


Assuntos
Ponte Cardiopulmonar/métodos , Coloides/uso terapêutico , Soluções Cristaloides/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Coloides/farmacologia , Soluções Cristaloides/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
13.
Nat Nanotechnol ; 13(6): 478-482, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29610527

RESUMO

Recent progress in synthetic nanotechnology and the ancient use of metals in food preservation and the antibacterial treatment of wounds have prompted the development of nanometallic materials for antimicrobial applications1-4. However, the materials designed so far do not simultaneously display antimicrobial activity and the capability of binding and capturing bacteria and spores. Here, we develop a one-step pyrolysis procedure to synthesize monodisperse superparamagnetic nickel colloidal nanocrystal clusters (SNCNCs), which show both antibacterial activity and the ability to bind Gram-positive (Bacillus subtilis) and Gram-negative (Escherichia coli) bacteria, as well as bacterial spores. The SNCNCs are formed from a rapid burst of nickel nanoparticles, which self-assemble slowly into clusters. The clusters can magnetically extract 99.99% of bacteria and spores and provide a promising approach for the removal of microbes, including hard-to-treat microorganisms. We believe that our work illustrates the exciting opportunities that nanotechnology offers for alternative antimicrobial strategies and other applications in microbiology.


Assuntos
Antibacterianos/química , Coloides/química , Nanopartículas de Magnetita/química , Níquel/química , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/isolamento & purificação , Coloides/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/prevenção & controle , Humanos , Nanopartículas de Magnetita/ultraestrutura , Níquel/farmacologia , Pirólise
14.
Int J Biol Macromol ; 108: 916-926, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29113895

RESUMO

Hydrocolloids from seaweeds (phycocolloids) have interesting functional properties like antiproliferative activity. Marine algae consumptions are linked to law cancer incidences in countries that traditionally consume marine products. In this study, we have investigated water-soluble sulfated polysaccharides isolated from the red seaweed Laurencia papillosa and determined their chemical characteristics and biological activities on the human breast cancer cell line MCF-7. Total polysaccharides were extracted and fractionated from L. papillosa and characterized using FTIR-ATR and NMR spectrometry. In addition, their approximate molar mass was determined by GPC method. The chemical characterization of purified polysaccharides reveals the presence of sulfated polysaccharides differentially dispersed in the algal cell wall. They are the three types of carrageenan, kappa, iota and lambda carrageenans, named LP-W1, -W2 and -W3 respectively. Biological effects and cytotoxicity of the identified of the three sulfated polysaccharide fractions were evaluated in MCF-7 cell line. Our results showed a significant inhibition of MCF-7 cell viability by dose-dependent manner for cells exposed to LP-W2 and LP-W3 polysaccharides for 24h. The mechanistic of LP fractions-mediated apoptosis in MCF-7 cells was demonstrated. The biological effects of L. papillosa SPs indicate that it may be a promising candidate for breast cancer prevention and therapy.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Coloides/química , Coloides/farmacologia , Laurencia/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Biomarcadores , Neoplasias da Mama , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Coloides/isolamento & purificação , Citometria de Fluxo , Humanos , Células MCF-7 , Espectroscopia de Ressonância Magnética , Peso Molecular , Extratos Vegetais/isolamento & purificação , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfatos/química
15.
Surgery ; 162(5): 1055-1062, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28774488

RESUMO

BACKGROUND: The main objective of this study was to compare the effect of perioperative administration of crystalloid versus colloid solutions and its impact on reversal of ileus after resection with primary anastomosis of intestine. We hypothesized that inclusion of colloids will improve the return of intestinal motility. METHODS: In a double-blinded clinical trial, 91 the American Society of Anesthesiologists I to III patients undergoing abdominal operation for resection with anastomosis of small or large intestine were randomized to receive either lactated Ringer solution crystalloid group or 6% hydroxyethyl starch colloid group to replace intraoperative fluid loss (blood loss + third space). The time to resume normal intestinal motility was the primary end point and the prevalence of composite postoperative complications was the secondary end point. RESULTS: Average duration of ileus was 86.7 ± 23.6 hours in crystalloid group and it lasted 73.4 ± 20.8 hours in colloid group (P = .006). While there was no difference in the frequency of postoperative nausea and vomiting between the 2 groups (P = .3), the actual vomiting occurred less frequently in colloid group (P = .02). Serum concentrations of potassium ion decreased significantly in both groups, whereas the degree of potassium changes was more remarkable in colloid group compared with crystalloid group (P = .03). Postoperative ileus did not correlate with sex, age, and the duration of operation. Duration of hospital stay was similar between the 2 groups. CONCLUSION: We concluded that administration of colloids as a part of perioperative fluid management improves intestinal motility and shortens the duration of ileus after gastrointestinal operations. This may improve the tolerance for enteral feeding and reduce ileus-related symptoms.


Assuntos
Anastomose Cirúrgica/efeitos adversos , Motilidade Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/cirurgia , Íleus/prevenção & controle , Soluções Isotônicas/administração & dosagem , Soluções para Reidratação/administração & dosagem , Abdome/cirurgia , Adulto , Idoso , Anestesia Epidural , Anestesia Geral , Coloides/administração & dosagem , Coloides/farmacologia , Soluções Cristaloides , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Método Duplo-Cego , Feminino , Hidratação/métodos , Trato Gastrointestinal/efeitos dos fármacos , Humanos , Derivados de Hidroxietil Amido/administração & dosagem , Derivados de Hidroxietil Amido/farmacologia , Íleus/etiologia , Intestinos/efeitos dos fármacos , Intestinos/cirurgia , Soluções Isotônicas/farmacologia , Laparotomia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Substitutos do Plasma/administração & dosagem , Substitutos do Plasma/farmacologia , Soluções para Reidratação/farmacologia , Lactato de Ringer
16.
Int J Pharm ; 526(1-2): 443-454, 2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-28473237

RESUMO

Studies have shown that nanoparticles (NPs) are cleared through the mononuclear phagocyte system (MPS). Pharmacokinetic studies of Doxil, DaunoXome, micellar doxorubicin (SP1049C) and small molecule (SM) doxorubicin were performed in SCID mice, Sprague-Dawley rats, and beagle dogs. An ex vivo MPS profiling platform was used to evaluate the interaction between the same agents, as well as colloid-forming and non-colloid forming SM drugs. In all species, the systemic clearance was highest for SP1049C and lowest for Doxil. With the exception of dog blood, the MPS screening results of mouse and rat blood showed that the greatest reduction in phagocytosis occurred after the ex vivo addition of SM-doxorubicin>SP1049C>DaunoXome>Doxil. The MPS profiling platform in rats, but not dogs, could differentiate between colloid forming and non-colloid forming drugs. The results of the MPS profiling platform were generally consistent with in vivo clearance rates of NP and SM anticancer drugs in mice and rats. This study suggests the MPS profiling platform is an effective method to screen and differentiate the important characteristics of NPs and colloid-forming drugs that affect their in vivo clearance. Implications of these findings on preclinical prediction of human clearance are discussed.


Assuntos
Coloides/farmacologia , Sistema Fagocitário Mononuclear/efeitos dos fármacos , Nanopartículas/química , Animais , Cães , Humanos , Camundongos , Camundongos SCID , Ratos , Ratos Sprague-Dawley
17.
J Trauma Acute Care Surg ; 82(1): 156-164, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27779578

RESUMO

BACKGROUND: Prehospital, small-volume resuscitation of combat casualties with a synthetic colloid (6% hydroxyethyl starch [HES] 670/0.75) has been recommended when blood or blood components are unavailable. We studied hemostatic effects of a newer synthetic colloid (6% HES, 130/0.4) compared with either a natural colloid (albumin) or to crystalloids in an uncontrolled hemorrhage model. METHODS: Spontaneously breathing New Zealand white rabbits (3.4 ± 0.1 kg) were anesthetized, instrumented, and subjected to a splenic injury with uncontrolled bleeding. Fifteen minutes after injury, rabbits were in shock (mean arterial pressure [MAP] = 26 ± 1.3 mm Hg, and received colloids (6% HES, 130/0.4 or 5% albumin at 15 mL/kg), or crystalloids (normal saline at 30 mL/kg or 5% hypertonic saline at 7.5 mL/kg) for resuscitation in two intravenous bolus injections (15 minutes apart) to raise their MAP to 65 mm Hg, n = 9/group. Animals were monitored for 2.5 hours or until death, and blood losses were measured. Blood samples were analyzed for arterial blood gas, complete blood count, and coagulation measures. RESULTS: There were no differences among groups in baseline measures and initial hemorrhage volume (11.9 ± 0.6 mL/kg) at 15 minutes postinjury. Twenty minutes after fluid resuscitation (1 hour postinjury), MAP was higher, shock indices were lower, and blood pH was higher in colloids versus. crystalloids groups (p < 0.05). Administration of 6% HES 130/0.4 colloid produced the largest hemodilution (54% decrease in hematocrit, p < 0.05 vs. hypertonic saline). Activated partial thromboplastin time increased approximately 35% above baseline in all groups except in 6% HES 130/0.4 group in which it doubled. Clot strength was reduced (15%) only in the 6% HES 130/0.4 group. 6% HES 130/0.4 resuscitation produced the largest blood loss and 33% survival rate that was not different than the crystalloid groups. Albumin produced the best hemostatic and survival outcomes (78%). CONCLUSION: Small-volume resuscitation with crystalloids appeared inadequate to treat hypovolemic shock and prevent death. 6% HES 130/0.4 was effective hemodynamically but detrimental to hemostasis. Albumin produced the best outcomes consistent with our previous observations. Further studies are needed to prove benefit of albumin solution as a possible resuscitation fluid for treating combat casualties at the point of injury.


Assuntos
Albuminas/farmacologia , Coloides/farmacologia , Hemostasia/efeitos dos fármacos , Derivados de Hidroxietil Amido/farmacologia , Soluções Isotônicas/farmacologia , Ressuscitação/métodos , Solução Salina Hipertônica/farmacologia , Choque Hemorrágico/tratamento farmacológico , Animais , Soluções Cristaloides , Modelos Animais de Doenças , Masculino , Coelhos
18.
Wounds ; 29(1): 1-9, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27852015

RESUMO

INTRODUCTION: The aim of this study was to investigate the effects of changing the application of Japanese honey to a hydrocolloid dressing (HCD) in between the inflammatory and proliferative phases on cutaneous wound healing in 8-week-old, BALB/cCrSlc male mice. MATERIALS AND METHODS: Mice were divided into 4 groups: acacia honey followed by a HCD, buckwheat flour honey followed by a HCD, Chinese milk vetch honey followed by a HCD, and a HCD alone (control group). All mice received 2 full-thickness wounds on both sides of the dorsum using a Disposable Biopsy Punch. The wounds of the control group were covered with a HCD, whereas wounds in the other groups were treated with 0.1 mL of the relevant type of honey until day 3 post-wound and then were covered with a HCD from days 4 to 14. RESULTS: In the experimental groups, the wound area ratio was significantly smaller in the inflammatory phase but significantly larger in the proliferative phase. Reepithelialization, collagen deposition, and wound contraction were significantly delayed compared with those in the control group. DISCUSSION: The re-expansion of the wounds in the proliferative phase could not be prevented, and reepithelialization, collagen deposition, and wound contraction were delayed compared with those upon the use of a HCD. CONCLUSION: The study's authors concluded that these methods do not promote cutaneous wound healing better than the use of a HCD alone.


Assuntos
Curativos Hidrocoloides , Coloides/farmacologia , Mel , Cicatrização/fisiologia , Ferimentos e Lesões/patologia , Administração Cutânea , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos BALB C
19.
Adv Skin Wound Care ; 29(11): 499-508, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27755049

RESUMO

OBJECTIVES: Diabetic patients are at increased risk of severe skin infections. Covering the wound as early as possible can prevent infection and shorten the course of treatment. In this study, the authors fabricated a waterproof and breathable composite liquid dressing (CLD) that formed a barrier to bacteria and shortened healing time of diabetic rat skin ulcers. METHODS: The CLD was prepared in a formulation that, on evaporation of the liquid carrier, acts as a waterproof, breathable coating on injured skin. The coating was analyzed for water resistance, moisture vapor transmission rate (MVTR), bacterial barrier properties, sustained-release function, and biosafety. A chemically induced rat model of diabetic foot ulcers was used to examine the wound healing effect of CLD and CLD that contained Dermlin (Yensen Biotech Co, Jiangyin, Jiangsu, China). The wound healing rate, histologic changes, and epidermal growth factor expression were also evaluated. RESULTS: The CLD functioned as an effective barrier against infection, was waterproof, had a suitable MVTR, and had effective biosafety. The synergistic effects of CLD and Dermlin had a rapid wound closure rate. Histologic analysis and measurement of epidermal growth factor expression through an in vivo test revealed that the possible mechanism of the CLD effects included the reduction of inflammation and promotion of cell proliferation. CONCLUSIONS: Early treatment with the CLD can prevent infection. In combination with Dermlin, the CLD may promote better wound closure in diabetic skin ulcers. The authors' study suggests a novel strategy for ulcer healing.


Assuntos
Diabetes Mellitus Experimental/complicações , Úlcera Cutânea/etiologia , Úlcera Cutânea/terapia , Cicatrização/fisiologia , Animais , Bandagens , Biópsia por Agulha , Coloides/farmacologia , Modelos Animais de Doenças , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Imuno-Histoquímica , Teste de Materiais , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Sensibilidade e Especificidade , Úlcera Cutânea/patologia , Cicatrização/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA