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1.
Gen Physiol Biophys ; 38(5): 369-378, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31411573

RESUMO

CD33 is a myeloid-associated marker and belongs to the sialic acid-binding immunoglobulin (Ig)-like lectin (Siglec) family. Such types of receptors are highly expressed in acute myeloid leukemia, which could be used in its treatment. CD33 shows high variability in its expression levels with still unknown reasons. Here, we investigated the CD33 expression of monocytes in human blood samples processed at different temperatures and in dependence on their phagocytic activity against opsonized Escherichia coli. The samples were stained by fluorescently labelled anti-human CD14 to specify the monocyte population, anti-human CD33 antibodies to evaluate CD33 expression and analyzed by flow cytometry and confocal laser scanning microscopy. In blood samples kept at 37°C or first pre-chilled at 0°C with subsequent warming up to 37°C, the percentage of CD33-positive monocytes as well as their relative fluorescence intensity was up-regulated compared to samples kept constantly at 0°C. After exposure to E. coli the CD33 relative fluorescence intensity of the monocytes activated at 37°C was 3 to 4 times higher than that of those cells kept inactive at 0°C. Microscopic analysis showed internalisation of CD33 due to its enhanced expression on the surface followed by engulfment of E. coli.


Assuntos
Monócitos/imunologia , Monócitos/metabolismo , Fagocitose , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Temperatura , Escherichia coli/imunologia , Humanos , Receptores de Lipopolissacarídeos/metabolismo , Monócitos/citologia , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/análise
2.
J Photochem Photobiol B ; 254: 112890, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38507943

RESUMO

This study explores the application of sustainable organic and biorefinery methods to increase the production of therapeutic hemp. Specifically, it focuses on Solodiol, Carmagnola, and Doctor Seedman strains. The study was carried out for 60 days in a highly controlled setting. It employed a unique combination of Murashige and Skoog (MS) media, supplemented with 2,4-D (0.5 mg/L) and kinetin (0.5 mg/L), and augmented with organic additions such as coconut water. This distinctive amalgamation facilitated extraordinary expansion across all varieties. The Solodiol strain demonstrated remarkable growth characteristics in terms of the number of branches, leaves, shoots, and height, whilst Carmagnola and Doctor Seedman indicated significant differences in diameter. Carmagnola, specifically, flourished in specific conditions: a strict 16-h period of light followed by 8 h of darkness, particularly when exposed to blue light. The Carmagnola strain, grown using MS feed (2StemMS), produced a hemp oil extract with a high concentration of 3.85%, compared to the Solodiol and Doctor Seedman strains, and also showcases their potential in promoting an environmentally friendly and therapeutically helpful medicinal hemp industry.


Assuntos
Cannabis , Folhas de Planta , Cinetina
3.
Nanomaterials (Basel) ; 9(3)2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30934597

RESUMO

Although riboflavin (RF) belongs to the water-soluble vitamins of group B, its solubility is low. Therefore, the application of micro-formulations may help to overcome this limiting factor for the delivery of RF. In this study we immobilized RF in newly developed albumin submicron particles prepared using the Co-precipitation Crosslinking Dissolution technique (CCD-technique) of manganese chloride and sodium carbonate in the presence of human serum albumin (HSA) and RF. The resulting RF containing HSA particles (RF-HSA-MPs) showed a narrow size distribution in the range of 0.9 to 1 µm, uniform peanut-like morphology, and a zeta-potential of -15 mV. In vitro release studies represented biphasic release profiles of RF in a phosphate buffered saline (PBS) pH 7.4 and a cell culture medium (RPMI) 1640 medium over a prolonged period. Hemolysis, platelet activation, and phagocytosis assays revealed a good hemocompatibility of RF-HSA-MPs.

4.
Artif Cells Nanomed Biotechnol ; 47(1): 241-249, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30663396

RESUMO

Blood compatibility is a key requirement to fulfil for intravenous administration of drug and oxygen carrier system. Recently, we published the fabrication of oxidised-dextran (Odex)-crosslinked protein particles by one-pot formulation. In the current study we investigate the haemocompatibility of these Odex - particles including albumin particles (Odex-APs) and haemoglobin particles (Odex-HbMPs). Odex-APs and Odex-HbMPs have a submicron size ranged 800-1000 nm with peanut-like shape and a negative surface charge. In vitro haemocompatibility assays included haemolysis test, indirect phagocytosis test and platelet activation test in human blood. Odex-APs and Odex-HbMPs did not provoke any undesirable effects on the blood cells. Firstly, the ratio of haemolysis after contacted with Odex-crosslinked protein particles were less than 5% and therefore the particles may be considered non-haemolytic. Secondly, the incubation of leukocyte with Odex-APs/HbMPs did not influence the phagocytosis of leukocyte. We conclude that our particles are not recognized by monocytes or granulocytes. Finally, exposure of Odex-APs/HbMPs to platelets did not cause an activation of platelets. Additionally, Odex-HbMP/AP did not enhance or attenuate agonist-induced platelet activation. We conclude that Odex-crosslinked protein particles exhibit a very good haemocompatibility and represent highly promising carriers for drugs or oxygen.


Assuntos
Albuminas/química , Albuminas/farmacologia , Dextranos/química , Hemoglobinas/química , Hemoglobinas/farmacologia , Teste de Materiais , Tamanho da Partícula , Hemólise/efeitos dos fármacos , Humanos , Fagocitose/efeitos dos fármacos , Ativação Plaquetária/efeitos dos fármacos
5.
Artif Cells Nanomed Biotechnol ; 46(sup3): S964-S972, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30388380

RESUMO

The coprecipitation-cross-linking-dissolution (CCD) technique for protein submicron particle fabrication was improved by omitting one preparation step using the macromolecular cross-linker, periodate-oxidized dextran (Odex, M.W. of 40 and 70 kDa). The coprecipitation and cross-linking of haemoglobin (Hb) were combined in one single step since the cross-linker is incorporated into the inorganic template, MnCO3, together with the protein. After removal of the MnCO3 templates by EDTA, the amount of entrapped Hb was 60 to 70% of the initial amount. This technique provides deformable Hb submicron particles (HbMP) with narrow size distribution between 800 and 1000 nm, uniform morphology and negative zeta-potential. More than 40% of Hb in the particles was able to carry oxygen over a storage period of 90 days. The results suggest that our new protein submicron particle fabrication technique minimizes the fabrication time and is very efficient and cost-effective.


Assuntos
Substitutos Sanguíneos/química , Substitutos Sanguíneos/síntese química , Hemoglobinas/química , Oxigênio/química , Animais , Bovinos , Tamanho da Partícula
6.
Eur J Pharm Biopharm ; 89: 201-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25500282

RESUMO

UV irradiation leads to the formation of reactive oxygen species (ROS). An imbalance between the antioxidant system and ROS can lead to cell damage, premature skin aging or skin cancer. To counteract these processes, antioxidants such as coenzyme Q10 (CoQ10) are contained in many cosmetics. To improve and optimize cell/tissue penetration properties of the lipophilic CoQ10, ultra-small lipid nanoparticles (usNLC) were developed. The antioxidant effectiveness of CoQ10-loaded usNLC compared to conventional nanocarriers was investigated in the human keratinocyte cell line HaCaT. Using confocal laser scanning microscopy investigations of the carriers additionally loaded with nile red showed a clear uptake into cells and their distribution within the cytoplasm. By use of the XTT cell viability test, CoQ10 concentrations of 10-50 µg/ml were shown to be non-toxic, and the antioxidant potential of 10 µg/ml CoQ10 loaded usNLC in the HaCaT cells was analyzed via electron paramagnetic resonance spectroscopy after cellular exposure to UVA (1J/cm(2)) and UVB (18 mJ/cm(2)) irradiation. In comparison with the CoQ10-loaded conventional carriers, usNLC-CoQ10 demonstrated the strongest reduction of the radical formation; reaching up to 23% compared to control cells without nanocarrier treatment. Therefore, usNLC-CoQ10 are very suitable to increase the antioxidant potential of skin.


Assuntos
Lipídeos/química , Lipídeos/farmacologia , Nanopartículas/administração & dosagem , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Pele/efeitos dos fármacos , Ubiquinona/análogos & derivados , Antioxidantes/farmacologia , Linhagem Celular , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Humanos , Queratinócitos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Envelhecimento da Pele/efeitos dos fármacos , Ubiquinona/metabolismo , Raios Ultravioleta/efeitos adversos
7.
Int J Pharm ; 477(1-2): 227-35, 2014 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-25455773

RESUMO

For the development of ultra-small NLC (usNLC) the determination of the required HLB (hydrophilic lipophilic balance) was found to be a suitable method, i.e., usNLC with a size below 50 nm were obtained by this method. Loading with 5% (w/w) coenzyme Q10 (Q10) led to usNLC with a size of about 85 nm. In comparison to classical NLC with a size of 230 nm and a nanoemulsion with similar size, the Q10 loaded usNLC show a higher release, a higher antioxidant capacity, and a better skin penetration for Q10. The reason for this is a flip-flop core-shell structure of the lipid matrix, i.e., the oil with dissolved active is surrounding the solid lipid based core. As the flip-flop structure was probably achieved by admixing high contents of liquid lipid, oil enriched usNLC might represent a novel and promising carrier system for the improved delivery of lipophilic actives.


Assuntos
Portadores de Fármacos/química , Lipídeos/química , Nanopartículas/química , Varredura Diferencial de Calorimetria , Liberação Controlada de Fármacos , Emulsões , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Propriedades de Superfície , Ubiquinona/análogos & derivados , Ubiquinona/química
8.
Int J Pharm ; 447(1-2): 213-7, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23438979

RESUMO

Coenzyme Q10 (CoQ10) acts as an antioxidant in the skin and is frequently contained in anti-aging products. In previous studies, it could be shown that nano-structured lipid carriers (NLC) with a size of about 230 nm are beneficial for the dermal delivery of CoQ10. They increased Q10 skin penetration when compared to equally sized nanoemulsion. In this study, ultra-small NLC were prepared with even smaller mean particles sizes of around 80 nm. The influence of this decrease of particle size was investigated in terms of skin permeation and penetration as well as physicochemical stability of the NLC. Improved dermal delivery of CoQ10 by ultra-small NLC could be achieved.


Assuntos
Antioxidantes/administração & dosagem , Portadores de Fármacos/administração & dosagem , Nanopartículas/administração & dosagem , Ubiquinona/análogos & derivados , Administração Cutânea , Animais , Antioxidantes/química , Portadores de Fármacos/química , Lipídeos/química , Nanopartículas/química , Tamanho da Partícula , Pele/metabolismo , Absorção Cutânea , Suínos , Ubiquinona/administração & dosagem , Ubiquinona/química
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