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1.
Rev Argent Microbiol ; 56(2): 175-186, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38336597

RESUMO

Peanuts (Arachis hypogaea L.) are among the most important leguminous crops in Argentina. During the growing season, they are frequently attacked by fungal diseases, including Thecaphora frezii. The spores of T. frezii are structures that confer resistance to this phytopathogen. The transition from teliospore to hypha is a characteristic process of some fungi, which is essential for completing their life cycle. Using the transcriptomes of teliospores and hyphae of T. frezii, we aimed to identify genes that were differentially expressed during this transition, and we found 134 up-regulated and 66 down-regulated genes, which would participate in different cellular processes such as: (a) cell cycle and DNA processing; (b) cell fate; (c) rescue, defense and cellular virulence; (d) detoxification by CYP450; (e) energy; (f) nutrient interaction and nutritional adaptation; (g) metabolism; (g) proteins with binding functions or cofactor requirements; (h) stress, cell differentiation and biogenesis of cell components; and (i) transport, cell communication and transcription. The identification of genes in T. frezii and their expression levels during different stages of differentiation could contribute to our understanding of the biological mechanisms in this fungus.


Assuntos
Arachis , Hifas , Esporos Fúngicos , Arachis/microbiologia , Hifas/genética , Hifas/crescimento & desenvolvimento , Esporos Fúngicos/genética , Doenças das Plantas/microbiologia , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Proteínas Fúngicas/genética , Transcriptoma , Perfilação da Expressão Gênica
2.
Polymers (Basel) ; 15(7)2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37050407

RESUMO

Diabetes mellitus (DM) is a highly prevalent disease affecting almost 10% of the world population; it is characterized by acute and chronic conditions. Diabetic patients have twenty-five times higher risk of going blind and developing cataracts early than the general population. Alpha-lipoic acid (LA) is a highly valuable natural antioxidant for the prevention and treatment of ophthalmic complications, such as diabetic keratopathy and retinopathy. However, its applicability is limited due to its low solubility in water; therefore, suitable systems are required for its formulation. In this work we developed an erodible insert based on Eudragit E100 (E PO) and Lipoic Acid (LA) for the delivery of this compound for the preventive treatment of ocular diseases especially in diabetic patients. Film evaluation was carried out by mechanical and thermal properties, mucoadhesivity, drug release, dynamic light scattering and corneal permeability as the concentration of LA increased. It was shown that upon LA release, it forms nanoparticles in combination with E PO that favor corneal permeation and LA retention in the cornea. These E PO-LA films also resulted non-irritable hence they are promising for their application in the treatment of ocular diseases.

3.
J Appl Microbiol ; 134(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36724262

RESUMO

AIMS: It is known that Thecaphora frezii produces peanut smut that generates numerous economic losses. For this reason, it is a priority to search for control strategies. In this sense, we investigated the lipid profile of this pathogen, as possible antifungal targets, regarding polar lipid composition, fatty acid profile, and transcriptional regulation of genes involved in each stage of the development. METHOD AND RESULTS: Lipids from T. frezii teliospores, basidiospores, and hyphae were analyzed by HPLC/CAD and CG/FID. We found differences in the unsaturation levels as well as in the long-chain fatty acids along the stages. Phosphatidylcholine was the main component in the three development stages, followed by cardiolipins. Phosphatidylinositol, phosphatidylethanolamine, and lyso-phosphatidylethanolamine were found in similar amounts in all stages. Although ergosterol was not detected, we found two unsaponifiable lipids. In addition, we found transcripts that encode 28 enzymes involved in the biosynthesis of three lipids by RNA-Seq. CONCLUSIONS: Thecaphora frezii shows changes in the composition of membrane lipids in different ontogenetic stages as well as in the expression of transcripts for enzymes involved in lipid biosynthesis.


Assuntos
Vias Biossintéticas , Fosfatidiletanolaminas , Ácidos Graxos/metabolismo , Lipídeos de Membrana
4.
Polymers (Basel) ; 13(24)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34960976

RESUMO

We describe the functional capability of a cross-linked hydrogel composed of sulfated glycosaminoglycans and a cationic cellulose by conducting trials on experimental animal models using intra-articular implants to treat an articular disease called osteoarthritis. Forty-eight mature New Zealand white rabbits were divided into three experimental groups: A, B, and C. Group A and B underwent unilateral anterior cruciate ligament transection (ACLT) of the right knee. Subsequently, both knees of group A were treated with the injectable formulation under study. Meanwhile, group B was treated with sterile PBS (placebo). The animals of group C were surgically operated in both knees: Commercial hyaluronic acid (HA) was implanted in the left knee, and the formulation under study was implanted in the right knee. After implantation, all specimens underwent several evaluations at 3, 6, and 12 months postoperatively. At 6 months, no significant differences were detected between the right and left knees of the different groups. However, significant differences were observed between both knees at 12 months in group C, with less cartilage damage in the right knees implanted with our hydrogel. Therefore, in vivo studies have demonstrated hydrogel safety, superior permanence, and less cartilage damage for long-term follow up 12 months after implantation for the formulation under study compared with commercial HA.

5.
Infect Dis Ther ; 10(4): 2511-2524, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34460083

RESUMO

INTRODUCTION: Sodium ibuprofenate in hypertonic saline (NaIHS) administered directly to the lungs by nebulization and inhalation has antibacterial and anti-inflammatory effects, with the potential to deliver these benefits to hypoxic patients. We describe a compassionate use program that offered this therapy to hospitalized COVID-19 patients. METHODS: NaIHS (50 mg ibuprofen, tid) was provided in addition to standard of care (SOC) to hospitalized COVID-19 patients until oxygen saturation levels of > 94% were achieved on ambient air. Patients wore a containment hood to diminish aerosolization. Outcome data from participating patients treated at multiple hospitals in Argentina between April 4 and October 31, 2020, are summarized. Results were compared with a retrospective contemporaneous control (CC) group of hospitalized COVID-19 patients with SOC alone during the same time frame from a subset of participating hospitals from Córdoba and Buenos Aires. RESULTS: The evolution of 383 patients treated with SOC + NaIHS [56 on mechanical ventilation (MV) at baseline] and 195 CC (21 on MV at baseline) are summarized. At baseline, NaIHS-treated patients had basal oxygen saturation of 90.7 ± 0.2% (74.3% were on supplemental oxygen at baseline) and a basal respiratory rate of 22.7 ± 0.3 breath/min. In the CC group, basal oxygen saturation was 92.6 ± 0.4% (52.1% were on oxygen supplementation at baseline) and respiratory rate was 19.3 ± 0.3 breath/min. Despite greater pulmonary compromise at baseline in the NaIHS-treated group, the length of treatment (LOT) was 9.1 ± 0.2 gs with an average length of stay (ALOS) of 11.5 ± 0.3 days, in comparison with an ALOS of 13.3 ± 0.9 days in the CC group. In patients on MV who received NaIHS, the ALOS was lower than in the CC group. In both NaIHS-treated groups, a rapid reversal of deterioration in oxygenation and NEWS2 scores was observed acutely after initiation of NaIHS therapy. No serious adverse events were considered related to ibuprofen therapy. Mortality was lower in both NaIHS groups compared with CC groups. CONCLUSIONS: Treatment of COVID-19 pneumonitis with inhalational nebulized NaIHS was associated with rapid improvement in hypoxia and vital signs, with no serious adverse events attributed to therapy. Nebulized NaIHS s worthy of further study in randomized, placebo-controlled trials (ClinicalTrials.gov: NCT04382768).

6.
Med Hypotheses ; 144: 110079, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32758897

RESUMO

The traditional formulation of ibuprofen is poorly soluble in water, so the administered dose must be 10 times higher than the dose required for a therapeutic effect. The development of a hydrosoluble form of ibuprofen can be a strategy to reach a high concentration in the lungs by using modern inhalation devices. Therefore, the development of an inhalable formulation with high bioavailability in the lungs was the leitmotiv of our investigation. The hypertonic ibuprofen solution to be nebulized (NIH) presents great relevant characteristics: bactericidal, virucidal, mucolytic and has a known anti-inflammatory property. Bactericidal and virucidal effects are related to the physico-chemical properties of Na-ibuprofenate as an amphipathic molecule. It has the capability to insert into the bilayer membranes destabilizing the structure, altering its biological properties and avoiding the duplication or infection. Our preliminary results indicate that the presence of this high ionic strength solution reduces 10 times the amount of ibuprofen necessary to kill bacteria, but also the time to kill 1x106 bacteria, from 4 h (in its absence) to only three minutes (in its presence). That was observed using Pseudomona aeruginosa, methicillin-resistant Staphylococcus aureus and Burkholderia cepacia. Also, "in vitro'' ibuprofen demonstrated virucidal activity against the so-called enveloped virus, a family that includes coronavirus strain (2019-nCoV). We observed too, the markedly reduced local inflammation in the airways after administering NIH lays on its ability to inhibit the enzyme cyclooxygenase and to markedly diminish reactive oxygen species (ROS). Other investigators also showed the importance of actin in the rapid spread of virus infection. Furthermore, reorganization of the actin filaments is a key step in lung inflammation induced by systemic inflammatory responses caused by SARS-CoV-2. These findings suggest that the interaction between actin proteins and S1 is involved in the 2019-nCoV infection and pathogenesis. Consequently, the possibility of interfering in this interaction could represent a valid hypothesis for the development of promising therapeutic and prevention strategies. In conclusion, we consider that treating people with COVID-19 with NIH may be beneficial and an opportunity to contribute for the current global health emergency.


Assuntos
Anti-Inflamatórios/administração & dosagem , Tratamento Farmacológico da COVID-19 , Ibuprofeno/administração & dosagem , Antibacterianos/administração & dosagem , Antivirais/administração & dosagem , Burkholderia cepacia , Inibidores de Ciclo-Oxigenase/administração & dosagem , Humanos , Inflamação/tratamento farmacológico , Staphylococcus aureus Resistente à Meticilina , Nebulizadores e Vaporizadores , Pseudomonas aeruginosa , Espécies Reativas de Oxigênio/metabolismo , SARS-CoV-2 , Solubilidade
7.
Sci Rep ; 10(1): 10191, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32576898

RESUMO

Having demonstrated the ability of monosialoganglioside GM1 micelles as oncology drug transporter, this work focuses on evaluating its application in an in vivo system, studying the toxicity and antitumoral effect of GM1-Ptx micellar formulation. The maximum tolerated dose (MTD) obtained after intravenous administration of GM1-Ptx in mice was 55 mg/kg and the 50% lethal dose (LD50) was 70 mg/kg. This value is higher than those described for the commercial formulations TAXOL and ABRAXANE, with LD50 of 30 and 45 mg/kg respectively. The antitumor activity, mortality and incidence of metastasis were studied on a murine model of mammary gland cancer. The GM1-Ptx formulation was administered i.v. at different doses for 9 weeks using empty GM1 micelles and saline as treatment controls. Once the treatments were completed, biochemical markers were quantified and histological tissue tests were performed. The most promising results were obtained with the treatment at a dose of 15 mg/kg/twice a week, condition in which a longer survival and significant reduction in the incidence of animals with metastasis, since only one 25% of the mice showed presence of pulmonary micro metastases.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Gangliosídeos/farmacologia , Paclitaxel/farmacologia , Animais , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Portadores de Fármacos/química , Masculino , Dose Máxima Tolerável , Camundongos , Camundongos Endogâmicos BALB C , Micelas , Polietilenoglicóis/química
8.
Pharmaceuticals (Basel) ; 11(2)2018 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-29772761

RESUMO

Ibuprofen (IBU-H), a widely used anti-inflammatory, also shows a marked antimicrobial effect against several bacterial species, including those involved in cystic fibrosis such as Pseudomona aeruginosa, methicillin resistant Staphylococcus aureus and Burkholderia cepacia complex. Additionally, our results show significant synergy between water soluble Na-ibuprofen (IBU-Na) and ionic strength. Salt concentrations above 0.5 M modify the zeta potential promoting the action of Na-IBU; thus, with 1 M sodium chloride, IBU-Na is ten times more efficient than in the absence of ionic strength, and the minimum effective contact time is reduced from hours to minutes. In short time periods, where neither IBU-Na nor controls with 1 M NaCl show activity, the combination of both leads to a reduction in the bacterial load. We also analyzed whether the changes caused by salt on the bacterial membrane also promoted the activity of other microbicide compounds used in cystic fibrosis like gentamicin, tobramycin and phosphomycin. The results show that the presence of ionic strength only enhanced the bactericidal activity of the amphipathic molecule of IBU-Na. In this respect, the effect of saline concentration was also reflected in the surface properties of IBU-Na, where, in addition to the clear differences observed between 145 mM and 1 M, singular behaviors were also found, different in each condition. The combination of anti-inflammatory activity and this improved bactericidal effect of Na-IBU in hypertonic solution provides a new alternative for the treatment of respiratory infections of fibrotic patients based on known and widely used compounds.

9.
Curr Drug Deliv ; 15(6): 850-859, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28925873

RESUMO

The purpose of this study was to evaluate the most appropriate conditions to generate silver nanoparticles (AgNPs) loaded with a potent antimycotic drug like amphotericin B (AmB), characterize the physicochemical properties, and to evaluate the cytotoxic effect and biological activity of these new nanostructures as a potential nanocarrier for hydrophobic drugs. It was determined that the optimal molar ratio between Ag and AmB is 1/1 given the uniformity of size around 170 nm of the nanoparticles generated as well as their strongly negative ζ potential of -35 mV, a condition that favors repulsions between AgNPs and inhibiting their aggregation. In this condition, only 0.8 mg.mL-1 of Ag is needed to solubilize 5 mg.mL-1 of AmB, a concentration currently used in commercial formulations. It is important to emphasize that the loading capacity (w/w) of this nanostructure is much higher than that of micellar and liposomal formulations. These AgNP-AmB nanoparticles retain both the bactericidal effect of silver and the cytotoxic and antifungal effect of AmB. However, it was shown that these nanoparticles are spontaneously associated with plasma lipoproteins (LDL and HDL), inhibiting their cytotoxic effects on red blood cells and on at least two cell lines, Vero and H1299 and slightly reducing its bactericidal effect on P. aeruginosa. In contrast, the antifungal effect of the formulation is maintained and is even higher than that when the nanoparticle is not associated with lipoproteins, indicating that this association is of the reversible type. The characterization of these nanoparticles is discussed as a potential new model formulation able to improve the antifungal therapeutic efficiency of AmB.


Assuntos
Anfotericina B/farmacologia , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Nanopartículas Metálicas/química , Pseudomonas aeruginosa/efeitos dos fármacos , Prata/farmacologia , Anfotericina B/química , Animais , Antibacterianos/química , Antifúngicos/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Chlorocebus aethiops , Eritrócitos/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Conformação Molecular , Tamanho da Partícula , Prata/química , Solubilidade , Propriedades de Superfície , Células Vero
10.
J Pharm Sci ; 105(1): 268-75, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26852858

RESUMO

Efficiency of mono-sialogangliosides to load Paclitaxel (Ptx) has recently been found to depend on the structure of the polysaccharide chain. In this study, we demonstrated that incorporation of only one more sialic acid into the ganglioside molecule, independently of its position, causes a 4-fold increase in Ptx-loading capacity, the maximum being at a 5:1 molar ratio (di-sialoganglioside/Paclitaxel, GD/Ptx). These complexes are stable in solution for at least 3 months, and over 90% of Ptx remains loaded in the micelles after extreme stress conditions such as high-speed centrifugation, lyophilization, or freeze-thaw cycles. Ganglioside micelles protect 50% of the initially loaded Ptx from alkaline hydrolysis after 24 h at pH 10. Dynamic light scattering studies revealed that GD micelles increase their size from 9 to 12 nm when loaded with Ptx. Transmission electron microscopy shows a homogeneous population of spherical micelles either with or without Ptx. In vitro biological activity was similar to that of the free drug. These results provide further options of self-assembled nanostructures of di- and tri-sialogangliosides with a higher loading capacity.


Assuntos
Antineoplásicos Fitogênicos/química , Gangliosídeos/química , Paclitaxel/química , Antineoplásicos Fitogênicos/efeitos adversos , Linhagem Celular Tumoral , Centrifugação , Desenho de Fármacos , Estabilidade de Medicamentos , Excipientes , Liofilização , Congelamento , Hemólise/efeitos dos fármacos , Humanos , Hidrólise , Técnicas In Vitro , Micelas , Paclitaxel/efeitos adversos , Tamanho da Partícula , Solubilidade
11.
Curr Pharm Des ; 22(22): 3429-44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26845328

RESUMO

During the last years we have seen an increasing number of reports describing new properties and potential applications of cationic polymers and derived nanostructures. This review gives a summary of their applications in drug delivery, the preparation methods for nano and microstructures and will attempt to give a glimpse on how their structure, chemical composition and properties may be affected or modulated as to make them suitable for an intended application as drug delivery nanocarriers. The compositional complexity with the existence of several reacting groups makes cationic nanostructures critically sensitive to the contribution of thermodynamic and kinetic parameters in the determination of the type and stability of a particular structure and its ability to respond to changes in environmental conditions in the right time frame. Curiously, and contrarily to what could be expected, despite the fact that cationic polymers can form strong electrostatic interactions the contribution of the entropic component has been often found to be very important for their association with negatively charged supramolecular structures. Some general considerations indicate that when considering a complex multimolecular system like a nanocarrier containing an active ingredient it is frequently possible to find conditions under which enthalpic and entropic contributions are compensated leading to stable structures with a marginal thermodynamic stability (free energy change close to zero) which make them able to respond relatively fast to changes in the environmental conditions and therefore suitable for the design of smart drug delivery systems. Like with other nanocarriers, it should always be kept in mind that the properties of cationic nanocarriers will depend not only on their chemical composition but also on the properties of the structures formed by them.


Assuntos
Biopolímeros/química , Sistemas de Liberação de Medicamentos , Nanoestruturas/química , Termodinâmica , Animais , Cátions/química , Portadores de Fármacos/química , Humanos , Cinética , Estrutura Molecular
12.
Biochim Biophys Acta ; 1848(10 Pt A): 2163-71, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26119566

RESUMO

Molecular interactions between the anti-cancer agent Paclitaxel (Ptx), and two gangliosides with different sialic acid content, GM1 and GD1a, were investigated using the Langmuir film balance technique. Ptx showed interfacial activity reducing the air/water surface tension by 18 mN·m(-1). However, the drug was able to insert into preformed ganglioside monolayers at much higher surface pressures, indicating a preferential interaction of Ptx with GM1 and GD1a. Compression isotherms of binary mixtures of Ptx and GM1 or GD1a also indicated non-ideal mixed monolayers in which the drug became stabilized at the interface in the presence of gangliosides. Ptx reached much higher surface pressure values in the mixed monolayers than those sustained in pure Ptx, although partial desorption of the drug from the interface into the subphase was also observed at high Ptx contents. The mean molecular area of the mixtures showed condensation, mainly in the case of GD1a, whereas Ptx induced a decrease in the compressibility of monolayers when mixed with either GM1 or GD1a. Additionally, Brewster angle microscopy analysis indicated that higher amounts of Ptx are present at the mixed ganglioside/Ptx interface when compared to pure drug monolayers. Finally, GD1a micelles increased in size in the presence of Ptx, whereas GM1 micelles kept their diameter, according to dynamic light scattering measurements, which could be explained by the different properties of ganglioside monolayers. The results obtained on ganglioside-Ptx interactions allowed interpreting the different Ptx loading capacity of GM1 and GD1a, enabling them to act as potential drug carriers.


Assuntos
Antineoplásicos/química , Gangliosídeo G(M1)/química , Gangliosídeos/química , Lipossomos/química , Nanocápsulas/química , Paclitaxel/química , Absorção Fisico-Química , Antineoplásicos/administração & dosagem , Difusão , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Nanocápsulas/administração & dosagem , Nanocápsulas/ultraestrutura , Paclitaxel/administração & dosagem , Tensão Superficial
13.
Int J Nanomedicine ; 10: 3377-87, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26005348

RESUMO

Doxorubicin (Dox) is an anthracycline anticancer drug with high water solubility, whose use is limited primarily due to significant side effects. In this study it is shown that Dox interacts with monosialoglycosphingolipid (GM1) ganglioside micelles primarily through hydrophobic interactions independent of pH and ionic strength. In addition, Dox can be incorporated even into GM1 micelles already containing highly hydrophobic paclitaxel (Ptx). However, it was not possible to incorporate Ptx into Dox-containing GM1 micelles, suggesting that Dox could be occupying a more external position in the micelles. This result is in agreement with a higher hydrolysis of Dox than of Ptx when micelles were incubated at alkaline pH. The loading of Dox into GM1 micelles was observed over a broad range of temperature (4°C-55°C). Furthermore, Dox-loaded micelles were stable in aqueous solutions exhibiting no aggregation or precipitation for up to 2 months when kept at 4°C-25°C and even after freeze-thawing cycles. Upon exposure to blood components, Dox-containing micelles were observed to interact with human serum albumin. However, the amount of human serum albumin that ended up being associated to the micelles was inversely related to the amount of Dox, suggesting that both could share their binding sites. In vitro studies on Hep2 cells showed that the cellular uptake and cytotoxic activity of Dox and Ptx from the micellar complexes were similar to those of the free form of these drugs, even when the micelle was covered with albumin. These results support the idea of the existence of different nano-domains in a single micelle and the fact that this micellar model could be used as a platform for loading and delivering hydrophobic and hydrophilic active pharmaceutical ingredients.


Assuntos
Doxorrubicina/química , Gangliosídeo G(M1)/química , Paclitaxel/química , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Estabilidade de Medicamentos , Células Hep G2/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Interações Hidrofóbicas e Hidrofílicas , Micelas , Concentração Osmolar , Paclitaxel/farmacocinética , Paclitaxel/farmacologia , Albumina Sérica/química , Solubilidade
14.
Curr Drug Deliv ; 12(4): 406-14, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25772153

RESUMO

In this work a thorough characterization of the GM1 micelle-Amphotericin B (AmB) interaction was performed. The micelle formation as well as the drug loading occurs spontaneously, although influenced by the physicochemical conditions, pH and temperature. The chromatographic profile of GM1-AmB complexes at different molar ratios shows the existence of two populations. The differential absorbance of GM1, monomeric and aggregate AmB, allowed us to discriminate the presence of all of them in both fractions. Thus, we noted that at higher proportion of AmB in the complex, increases the larger population which is composed mainly of aggregated AmB. The physical behavior of these micelles shows that both GM1- AmB complexes were stable in solution for at least 30 days. However upon freeze-thawing or lyophilization-solubilization cycles, only the smallest population, enriched in monomeric AmB, showed a complete solubilization. In vitro, GM1-AmB micelles were significantly less toxic on cultured cells than other commercial micellar formulations as Fungizone, but had a similar behavior to liposomal formulations as Ambisome. Regarding the antifungal activity of the new formulation, it was very similar to that of other formulations. The characterization of these GM1-AmB complexes is discussed as a potential new formulation able to improve the antifungal therapeutic efficiency of AmB.


Assuntos
Anfotericina B/química , Antifúngicos/química , Portadores de Fármacos , Gangliosídeo G(M1)/química , Anfotericina B/farmacologia , Animais , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Chlorocebus aethiops , Liofilização , Gangliosídeo G(M1)/toxicidade , Hemólise/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Micelas , Testes de Sensibilidade Microbiana , Solubilidade , Tecnologia Farmacêutica/métodos , Temperatura , Células Vero
15.
Colloids Surf B Biointerfaces ; 114: 201-8, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24189195

RESUMO

We reported herein the study and characterization of films obtained by casting of chitosan solutions in perfluorinated acids, trifluoroacetic (TFA), perfluoropropionic (PFPA), and perfluorooctanoic (PFOA). The films were characterized by FTIR, solid state (13)C NMR, X-ray, AFM, contact angle, thermogravimetric effluent analysis by mass spectrometry, and rheology. The results showed a marked influence of chain length of the perfluorinated acids on the hydrophobic/hydrophilic ratio of the modified chitosan films which was evidenced by the different characteristics observed. The material that showed greater surface stability was chitosan-PFOA. Chitosan film with the addition of PFOA modifier became more hydrophobic, thus water vapor permeability diminished compared to chitosan films alone, this new material also depicted bacterial adhesion which, together with the features already described, proves its potential in applications for bioreactor coating.


Assuntos
Ácidos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Quitosana/farmacologia , Fluorocarbonos/farmacologia , Pseudomonas aeruginosa/fisiologia , Caprilatos/farmacologia , Linhagem Celular Tumoral , Contagem de Colônia Microbiana , Módulo de Elasticidade/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Viabilidade Microbiana/efeitos dos fármacos , Microscopia de Força Atômica , Peso Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Reologia/efeitos dos fármacos , Termodinâmica , Termogravimetria , Ácido Trifluoracético/farmacologia , Difração de Raios X
16.
J Control Release ; 162(3): 619-27, 2012 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-22877735

RESUMO

We demonstrate herein that taxanes (paclitaxel (Ptx) and docetaxel (Dtx)) can be spontaneously loaded into ganglioside nanomicelles. The efficiency of gangliosides to solubilize taxanes was highly dependent on their self-aggregating structure. Thus, GM3 that forms unilamellar vesicles was less efficient to solubilize taxanes than gangliosides that form micelles (i.e. GM1 and GM2). Sialic acid cyclization of GM1 by acid treatment led to an important reduction in its capacity to solubilize taxanes, as also did the replacement of the fatty acid of ceramide by a dicholoracetyl group. Water solubility of paclitaxel (Ptx) is less than 1 µg mL⁻¹ and increased up to 6.3mg.mL⁻¹ upon its association with GM1 micelles. The incorporation of Ptx in GM1 reached an optimum at GM1/Ptx 20/1 molar ratio when performed at room temperature. An increase in the solubilization capacity of GM1 micelles was observed upon dehydration of their polar head group by pre-treatment at 55 °C. Loading of Ptx into the micelle induced a structural reorganization that led to an important protection of Ptx reducing its hydrolysis at alkaline pH. Diffusion of either GM1 or Ptx was restricted upon mixed-micelle formation indicating that they are kinetically more stable than pure ganglioside micelles. X-ray powder diffraction of lyophilized GM1 micelles with Ptx showed a change in their internal structure from a crystalline state to completely amorphous. Taxane-ganglioside mixed micelles were stable in solution for at least 4months and also upon freeze-thawing or lyophilization-solubilization cycles. Upon mixing with human blood constituents, GM1/Ptx micelles did not induce hemolysis or platelet aggregation and were spontaneously covered with human serum albumin (HSA), which could aid in the delivery of micellar content to tumors. In vitro antimitotic activity of GM1/Ptx mixed micelles was qualitatively equivalent to that of free drug in DMSO solution.


Assuntos
Antineoplásicos/química , Portadores de Fármacos/química , Gangliosídeos/química , Micelas , Paclitaxel/química , Taxoides/química , Antineoplásicos/administração & dosagem , Plaquetas/efeitos dos fármacos , Plaquetas/fisiologia , Células Cultivadas , Docetaxel , Portadores de Fármacos/administração & dosagem , Estabilidade de Medicamentos , Eritrócitos/efeitos dos fármacos , Eritrócitos/fisiologia , Gangliosídeos/administração & dosagem , Hemólise , Humanos , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Paclitaxel/administração & dosagem , Agregação Plaquetária , Solubilidade , Taxoides/administração & dosagem
17.
Colloids Surf B Biointerfaces ; 91: 84-9, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22093374

RESUMO

Eudragit E100 (E100) is a cationic methacrylate polymer that interacts with viral and cell membranes. We studied the effect of pH, ionic strength and the presence of lipid monolayers on the surface activity of the polymer. E100 forms stable monolayers at the air-water interface, either by spreading or when added into the subphase. This behavior is highly influenced by the pH and saline concentration of the subphase. At pH 5 or higher, the adsorption of the polymer to the air-water interface begins immediately after its injection into the subphase, while at pH below 5 E100 remains in the subphase with a particularly slow adsorption to the interface. In addition, low ionic strength (10 mM) in the subphase results in a fast adsorption of the polymer to the interface, even at pH under 5. On the other hand, in the presence of non-ionic (cholesterol) or anionic (monosialoganglioside) lipid monolayers, E100 shows a fast adsorption to the interface, [comma] reaching surface pressures of 25 and 36 mN m(-1), respectively. However, E100 barely interacts with monolayers of a zwitterionic lipid (hydrogenated soy lecithin) with a cut-off pressure of 11 mN m(-1). The interaction of E100 with GM1 micelles in the subphase reduces its surface activity. Altogether these results show that E100 can effectively penetrate into model membranes and that its amphipathic character is largely dependent on the chemical composition of the aqueous environment and the lipid composition of the membrane.


Assuntos
Acrilatos/química , Lipídeos/química , Polímeros/química , Concentração de Íons de Hidrogênio , Concentração Osmolar
18.
Genet Test Mol Biomarkers ; 16(2): 130-3, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21854194

RESUMO

AIMS: The selection of the most appropriate treatment for several diseases relies on a number of factors such as environment, age, gender, and nutrition. Additionally, the contribution of different genetic polymorphisms to treatment efficacy has been largely recognized. The lack of information on the pharmacogenetic profile of our population prompted us to analyze the frequency of polymorphisms known to be relevant to achieve treatment efficacy with different therapeutic agents in viral infectious diseases, such as Hepatitis C and AIDS. RESULTS: The allelic frequencies for the wild-type variant of the genes analyzed were cytochrome P450 2B6 (CYP2B6; rs3745274; 516G) 0.618 (95% confidence interval [CI]: 0.523, 0.711), chemokine coreceptor 5 (CCR5; rs333) 0.961 (95% CI: 0.942, 0.98), histocompatibility complex P5 (HCP5; rs2395029; 335T) 0.971 (95% CI: 0.937, 1), and interleukin 28B (IL28B; rs12979860; 12007005C) 0.656 (95% CI: 0.564, 0.747), respectively. CONCLUSIONS: Our data indicate that the genetic profile of the population studied is similar to that reported for other Caucasian populations, with only slight differences for CYP2B6. Noteworthy, the considerable number of patients carrying CYP2B6 (516T) and IL28B (12007005T) alleles underlies the importance of considering pharmacogenetic testing before starting drug therapy protocols to prevent toxicity and/or lack of effectiveness in AIDS or hepatitis C virus infections.


Assuntos
Hidrocarboneto de Aril Hidroxilases/genética , Interleucinas/genética , Complexo Principal de Histocompatibilidade/genética , Oxirredutases N-Desmetilantes/genética , Polimorfismo Genético , Receptores CCR5/genética , População Branca/genética , Adolescente , Adulto , Argentina , Citocromo P-450 CYP2B6 , Feminino , Frequência do Gene , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Hepatite C/tratamento farmacológico , Hepatite C/genética , Humanos , Interferons , Masculino , Pessoa de Meia-Idade , Farmacogenética , RNA Longo não Codificante , RNA não Traduzido , Adulto Jovem
19.
Colloids Surf B Biointerfaces ; 89: 23-8, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21925848

RESUMO

We investigated the nature and stability of the interactions established between polyquaternium (PQ10) and perfluorodecanoic acid (PFDA) in terms of different variables such as composition, ionic strength, pH and temperature. The PQ10-PFDA complex formation is interpreted in view of electrostatic associations between carboxylic and quaternary amino group. The properties of the systems were characterized by rheology analysis. The adhesive properties of complex were also assessed. One of the macroscopic features of the new material formed in solution was the increase in viscosity from 6 Pas for 1% PQ10 (MW 1.7×10(6) g mol(-1)) to about 1000 Pas by the addition of enough PFDA to reach 1:0.5 ammonium:carboxylic group molar ratio. At this proportion, PQ10 and PFDA form a network structure with a maximum viscosity and storage modulus. This maximum coincides with an increased mucoadhesive work.


Assuntos
Celulose/química , Ácidos Decanoicos/química , Fluorocarbonos/química , Hidrogéis , Área Sob a Curva , Concentração de Íons de Hidrogênio , Concentração Osmolar , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier
20.
Clin Biochem ; 44(13): 1058-1061, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21723269

RESUMO

OBJECTIVES: To determine the frequencies of relevant allelic variants in oncology for the GSTP1, DPYD, FCGR2A, FCGR3A and CCND1 genes in a population from Central Argentina. To compare the allelic distribution found with the frequencies reported for other ethnic groups. DESIGN AND METHODS: Genotyping was carried out in a total of 102 unrelated Argentinian subjects. FCGR3A (rs396991) was detected using allele specific polymerase chain reaction (PCR) assay, while GSTP1 (rs1695), DPYD (rs3918290), FCGR2A (rs1801274) and CCND1 (rs9344) variants were assessed by PCR-restriction fragment length polymorphism (PCR-RFLP). RESULTS: The allele frequencies for GSTP*1B, DPYD*2A, FCGR2A (131R), FCGR3A (158F) and CCND1 (870G) in Argentinians were 0.35, 0.005, 0.41, 0.77 and 0.47, respectively. CONCLUSIONS: We found that the Argentinian population tested resembles other Caucasians populations, especially Spaniards; yet the differences in allele distribution with other Caucasian groups, uncover population admixture with native Amerindian and other ethnic groups, consistent with the well documented immigration flows landing Argentina from several countries.


Assuntos
Ciclina D1/genética , Etnicidade/genética , Genes Neoplásicos , Glutationa S-Transferase pi/genética , Receptores de IgG/genética , Argentina/epidemiologia , Argentina/etnologia , Di-Hidrouracila Desidrogenase (NADP)/genética , Emigração e Imigração , Perfilação da Expressão Gênica , Frequência do Gene , Variação Genética , Genótipo , Humanos , Grupos Populacionais/genética
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