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1.
Int J Mol Sci ; 25(1)2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38203673

RESUMEN

Delivery systems for biologically active substances such as proanthocyanidins (PCANs), produced in the form of electrospun nonwoven through the electrospinning method, were designed using a polymeric blend of poly(L-lactide-co-glycolide) (PLGA)and poly[(R,S)-3-hydroxybutyrate] ((R,S)-PHB). The studies involved the structural and thermal characteristics of the developed electrospun three-dimensional fibre matrices unloaded and loaded with PCANs. In the next step, the hydrolytic degradation tests of these systems were performed. The release profile of PCANs from the electrospun nonwoven was determined with the aid of UV-VIS spectroscopy. Approximately 30% of the PCANs were released from the tested electrospun nonwoven during the initial 15-20 days of incubation. The chemical structure of water-soluble oligomers that were formed after the hydrolytic degradation of the developed delivery system was identified through electrospray ionization mass spectrometry. Oligomers of lactic acid and OLAGA oligocopolyester, as well as oligo-3-hydroxybutyrate terminated with hydroxyl and carboxyl end groups, were recognized as degradation products released into the water during the incubation time. It was also demonstrated that variations in the degradation rate of individual mat components influenced the degradation pattern and the number of formed oligomers. The obtained results suggest that the incorporation of proanthocyanidins into the system slowed down the hydrolytic degradation process of the poly(L-lactide-co-glycolide)/poly[(R,S)-3-hydroxybutyrate] three-dimensional fibre matrix. In addition, in vitro cytotoxicity and antimicrobial studies advocate the use of PCANs for biomedical applications with promising antimicrobial activity.


Asunto(s)
Antiinfecciosos , Proantocianidinas , Humanos , Poliésteres , Bolsa Periodontal , Ácido 3-Hidroxibutírico , Sistemas de Liberación de Medicamentos , Antiinfecciosos/farmacología , Hidroxibutiratos , Poli A , Agua
2.
Molecules ; 27(12)2022 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-35744897

RESUMEN

Green synthesis of silver-containing nanocomposites based on polylactide (PLA) was carried out in two ways. With the use of green tea extract, Ag+ ions were reduced to silver nanoparticles with their subsequent introduction into the PLA (mechanical method) and Ag+ ions were reduced in the polymer matrix of PLA-AgPalmitate (PLA-AgPalm) (in situ method). Structure, morphology and thermophysical properties of nanocomposites PLA-Ag were studied by FTIR spectroscopy, wide-angle X-ray scattering (WAXS), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) methods. The antimicrobial, antiviral, and cytotoxic properties were studied as well. It was found that the mechanical method provides the average size of silver nanoparticles in the PLA of about 16 nm, while in the formation of samples by the in situ method their average size was 3.7 nm. The strong influence of smaller silver nanoparticles (3.7 nm) on the properties of nanocomposites was revealed, as with increasing nanosilver concentration the heat resistance and glass transition temperature of the samples decreases, while the influence of larger particles (16 nm) on these parameters was not detected. It was shown that silver-containing nanocomposites formed in situ demonstrate antimicrobial activity against gram-positive bacterium S. aureus, gram-negative bacteria E. coli, P. aeruginosa, and the fungal pathogen of C. albicans, and the activity of the samples increases with increasing nanoparticle concentration. Silver-containing nanocomposites formed by the mechanical method have not shown antimicrobial activity. The relative antiviral activity of nanocomposites obtained by two methods against influenza A virus, and adenovirus serotype 2 was also revealed. The obtained nanocomposites were not-cytotoxic, and they did not inhibit the viability of MDCK or Hep-2 cell cultures.


Asunto(s)
Antiinfecciosos , Nanopartículas del Metal , Nanocompuestos , Antibacterianos/química , Antiinfecciosos/farmacología , Antivirales/farmacología , Escherichia coli , Iones , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Nanocompuestos/química , Poliésteres/química , Pseudomonas aeruginosa , Plata/química , Plata/farmacología , Staphylococcus aureus
3.
Clin Exp Rheumatol ; 39 Suppl 129(2): 83-87, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33200729

RESUMEN

OBJECTIVES: To evaluate the autoantibody profile in eosinophilic granulomatosis and polyangiitis (EGPA) patients. METHODS: 33 EGPA patients were tested for anti-neutrophil cytoplasmic antibodies (ANCA), antinuclear antibodies (ANA), rheumatoid factor (RF), anti-alpha-enolase antibodies, and anti-eosinophil peroxidase (EPO) antibodies. Granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), hypereosinophilic syndrome (HES), rheumatoid arthritis (RA), primary biliary cirrhosis (PBC) patients and healthy subjects were tested as a control group. RESULTS: Anti-alpha-enolase antibodies were positive in 82% of EGPA patients at high titers. Although a high sensitivity was shown for an anti-alpha-enolase antibody titer above 1/100 (82%), the specificity for EGPA remained low (44%) (AUC=0.653, p=0.008). Anti-alpha-enolase antibodies predominated in males with EGPA (p=0.048) and were associated with skin involvement (p=0.040). Most of the EGPA patients positive for anti-alpha enolase antibodies (20 out of 27) had a negative indirect immunofluorescence test (IFT) for ANCA. ANCA were positive in 8 EGPA patients (24%) with a perinuclear pattern in all but one patient. The ANCA-target antigen was myeloperoxidase (MPO) and/or alpha-enolase. A usually fine-speckled ANA pattern was observed in 42% of the EGPA patients. RF was positive in 1 (6%) of the 18 EGPA patients tested. There was no association between the presence and levels of autoantibodies and EGPA disease activity. None of the patients and controls was positive for anti-EPO antibodies. CONCLUSIONS: Alpha-enolase may be a target of autoimmunity in EGPA patients and shows usually negative ANCA IFT results.


Asunto(s)
Granulomatosis con Poliangitis , Poliangitis Microscópica , Anticuerpos Anticitoplasma de Neutrófilos , Humanos , Masculino , Peroxidasa , Fosfopiruvato Hidratasa
4.
Vet Ophthalmol ; 24(2): 125-155, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33369040

RESUMEN

OBJECTIVE: To describe functional and structural features of presumed cancer-associated retinopathy (CAR) mimicking sudden acquired retinal degeneration syndrome (SARDS) in dogs and describe treatment outcomes. ANIMALS: Subjects were 17 dogs from 8 eight US states and Canada diagnosed with SARDS or immune-mediated retinitis (IMR) by 12 ophthalmologists. Nine eyes from seven deceased patients were used for microarray (MA), histology, or immunohistochemical (IHC) analysis. PROCEDURES: Dogs underwent complete ophthalmic examination, including retinal photography, optical coherence tomography (OCT), chromatic pupil light reflex testing (cPLR), and electroretinography (ERG), in addition to complete systemic examination. Histology, microarray, and IHC analysis were performed in CAR retinas to evaluate histological and molecular changes in retinal tissue. RESULTS: None of the patients evaluated satisfied previously established criteria for diagnosis of SARDS (flat ERG+ no red - good blue PLR), and all were diagnosed with IMR. All patients were diagnosed with a cancer: meningioma (24%), sarcoma (18%), pituitary tumor (12%), and squamous cell carcinoma (12%), other (34%). Median survival time was 6 months from diagnosis (range 1-36 months). Most frequent systemic abnormalities were as follows: proteinuria (78%); elevated liver enzymes (47%); and metabolic changes (PU/PD, polyphagia - 24%). Immunosuppressive therapy resulted in the reversal of blindness in 44% of treated patients, with 61% of all treated patients recovering and/or maintaining vision. Median time for preservation of vision was 5 months (range 1-35 months). CONCLUSIONS: Observed changes are highly suggestive of immune-mediated damage in IMR-CAR eyes. A relatively high percentage of patients with CAR responded positively to immunosuppressive therapy.


Asunto(s)
Enfermedades de los Perros/diagnóstico , Síndromes Paraneoplásicos Oculares/veterinaria , Degeneración Retiniana/veterinaria , Animales , Autoanticuerpos/sangre , Diagnóstico Diferencial , Enfermedades de los Perros/inmunología , Enfermedades de los Perros/fisiopatología , Perros , Electrorretinografía/veterinaria , Femenino , Fondo de Ojo , Masculino , Síndromes Paraneoplásicos Oculares/diagnóstico , Síndromes Paraneoplásicos Oculares/inmunología , Síndromes Paraneoplásicos Oculares/fisiopatología , Degeneración Retiniana/diagnóstico , Degeneración Retiniana/inmunología , Degeneración Retiniana/fisiopatología
5.
Molecules ; 26(16)2021 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-34443448

RESUMEN

Following our previous studies on the molecular level structure of (co)oligoesters obtained via anionic homo- and co-polymerization of novel ß-substituted ß-lactones, prepared by the atmospheric pressure carbonylation reaction of respective epoxides, the boric acid biocatalyzed ring-opening (co)polymerization of δ-valerolactone has been studied. As a co-monomer the 6-methy-ε-caprolactone, prepared by the one-pot oxidation of respective alcohol, and ethylene glycol as polymerization initiator were used. The obtained copolymers were characterized by 1H-NMR, GPC and ESI-MS, respectively in order to confirm their chemical structures and identity. Subsequently, tandem mass spectrometry (MS-MS studies) via collision-induced dissociation were utilized to characterize the fragmentation pattern. ESI-MS and NMR analyses confirmed the formation of random linear copolymer chains composed of different polyester repeat units. MS-MS experiments showed that fragmentation proceeds via ester bound cleavage along the (co)polyester chains. The innovative aspect of this contribution is related to the elaboration of the telechelic (co)polymers end-capped with hydroxyl end groups and well-defined molecular architectures, which could facilitate the development of new flexible macromolecular systems for potential biomedical applications.

6.
Clin Immunol ; 210: 108317, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31770612

RESUMEN

Autoantibodies (AAbs) against retinal antigens can be found in patients with cancer and unexplained vision loss unrelated to the cancer metastasis. Cancer-associated retinopathy (CAR) is a rare paraneoplastic visual syndrome mediated by AAbs. Our goal was to determine whether CAR patients with different malignancies have a specific AAb or repertoire of AAbs that could serve as biomarkers for retinal disease. We found AAbs against 12 confirmed retinal antigens, with α-enolase being the most frequently recognized. The significant finding of the study was a high incidence of anti-aldolase AAbs in colon-CAR, anti-CAII in prostate-CAR, and anti-arrestin in skin melanoma patients thus these AAbs could serve as biomarkers in the context of clinical presentation and could support the diagnosis of CAR. However, a lack of AAb restriction to any one antigenic protein or to one retinal cellular location makes screening for a CAR biomarker challenging.


Asunto(s)
Autoanticuerpos/sangre , Biomarcadores de Tumor/sangre , Neoplasias del Colon/inmunología , Síndromes Paraneoplásicos Oculares/inmunología , Neoplasias de la Próstata/inmunología , Retina/patología , Anciano , Arrestina/inmunología , Autoantígenos/inmunología , Neoplasias del Colon/diagnóstico , Neoplasias del Colon/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndromes Paraneoplásicos Oculares/diagnóstico , Síndromes Paraneoplásicos Oculares/epidemiología , Fosfopiruvato Hidratasa/inmunología , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/epidemiología , Retina/inmunología , Estados Unidos/epidemiología
7.
Biomacromolecules ; 21(5): 1802-1811, 2020 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-31967794

RESUMEN

Chronic wounds are often recalcitrant to treatment because of high microbial bioburden and the problem of microbial resistance. Silver is a broad-spectrum natural antimicrobial agent with wide applications extending to proprietary wound dressings. Recently, silver nanoparticles have attracted attention in wound management. In the current study, the green synthesis of nanoparticles was accomplished using a natural reducing agent, curcumin, which is a natural polyphenolic compound that is well-known as a wound-healing agent. The hydrophobicity of curcumin was overcome by its microencapsulation in cyclodextrins. This study demonstrates the production, characterization of silver nanoparticles using aqueous curcumin:hydroxypropyl-ß-cyclodextrin complex and loading them into bacterial cellulose hydrogel with moist wound-healing properties. These silver nanoparticle-loaded bacterial cellulose hydrogels were characterized for wound-management applications. In addition to high cytocompatibility, these novel dressings exhibited antimicrobial activity against three common wound-infecting pathogenic microbes Staphylococcus aureus, Pseudomonas aeruginosa, and Candida auris.


Asunto(s)
Curcumina , Ciclodextrinas , Nanopartículas del Metal , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Vendajes , Celulosa , Hidrogeles , Plata
8.
Molecules ; 25(1)2019 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-31905750

RESUMEN

In the investigation presented here the synthesis of new lariat ether derivative obtained from the modification of tetrapyrrolidinyl-PNP-crown ether macrocycle is described. The polyheterotopic molecular coreceptor consisted of the replacement of chlorine atoms with an optically active (S)-(1-benzylpyrrolidin-2-yl) methanamine. The structure was confirmed by using elemental analysis, mass spectrometry, and NMR spectroscopy. This work covers results concerning the complexing properties of the new ligand towards Ag+, Cu2+, Co2+, Ni2+, and Zn2+ ions. The formation of non-covalent complexes of 1:1 stoichiometry with the Cu2+, Co2+, Ni2+, and Zn2+ ions have been confirmed by mass spectrometry. Due to the previous work and application possibilities, a large emphasis was put on the investigation of the complexation ability of lariat ether with silver (I) cation to determine stability constants by direct potentiometric method. In this case, the formation of four different forms of complexes AgL, Ag2L, Ag3L, and Ag4L has been proved. The observed unusual binding through the nitrogen atoms from the exocyclic substituents may provide the structural unit to build a new coordination polymers.


Asunto(s)
Aminas/química , Éteres Corona/química , Espectrometría de Masas , Iones/química , Ligandos , Espectroscopía de Resonancia Magnética , Metales/química , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem
9.
Biomacromolecules ; 19(2): 511-520, 2018 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-29261293

RESUMEN

The herbicide 2-methyl-4-chlorophenoxyacetic acid (MCPA) conjugated with poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) was prepared via a melt transesterification route. The resultant bioactive oligomer was then mixed with a blend of polylactide (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) with different loadings to manufacture films to be used as a bioactive, biodegradable mulch to deliver the herbicide to target broadleaf weed species. The biological targeting of the MCPA-PHBV conjugate in the mulch film was investigated under glasshouse conditions using faba bean (Vicia faba) as a selective (nontarget) model crop species having broadleaf morphology. The presence of the MCPA-PHBV conjugate in the biodegradable PBTA/PLA blend was shown to completely suppress the growth of broadleaf weed species while displaying only a mild effect on the growth of the model crop. The degradation of the mulch film under glasshouse conditions was quite slow. The release of the MCPA-PHBV during this process was detected using NMR, GPC, EDS, and DSC analyses, indicating that the majority of the MCPA diffused out after MCPA-PHBV conjugate bond scission. These data provide a strong "proof of concept" and show that this biodegradable, bioactive film is a good candidate for future field applications and may be of wide agricultural applicability.


Asunto(s)
Ácido 2-Metil-4-clorofenoxiacético , Poliésteres , Vicia faba/crecimiento & desarrollo , Control de Malezas , Ácido 2-Metil-4-clorofenoxiacético/química , Ácido 2-Metil-4-clorofenoxiacético/farmacología , Poliésteres/química , Poliésteres/farmacología
10.
Molecules ; 23(8)2018 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-30110952

RESUMEN

In this study, low molecular weight poly(δ-valerolactone) (PVL) was synthesized through bulk-ring openings polymerization of δ-valerolactone with boric acid (B(OH)3) as a catalyst and benzyl alcohol (BnOH) as an initiator. The resulting homopolymer was characterized with the aid of nuclear magnetic resonance (NMR) and mass spectrometry (MS) techniques to gain further understanding of its molecular structure. The electrospray ionization mass spectrometry (ESI-MS) spectra of poly(δ-valerolactone) showed the presence of two types of homopolyester chains-one terminated by benzyl ester and hydroxyl end groups and one with carboxyl and hydroxyl end groups. Additionally, a small amount of cyclic PVL oligomers was identified. To confirm the structure of PVL oligomers obtained, fragmentation of sodium adducts of individual polyester molecules terminated by various end groups was explored in ESI-MSn by using collision induced dissociation (CID) techniques. The ESI-MSn analyses were conducted both in positive- and negative ion mode. The comparison of the fragmentation spectra obtained with proposed respective theoretical fragmentation pathways allowed the structure of the obtained oligomers to be established at the molecular level. Additionally, using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), it was proven that regardless of the degree of oligomerization, the resulting PVL samples were a mixture of two types of linear PVL oligomers differing in end groups and containing just a small amount of cyclic oligomers that tended to be not visible at higher molar masses.


Asunto(s)
Ácidos Bóricos/química , Estructura Molecular , Polímeros/química , Pironas/química , Catálisis , Espectroscopía de Resonancia Magnética , Peso Molecular , Poliésteres/química , Polimerizacion , Polímeros/síntesis química , Pironas/síntesis química , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masas en Tándem
11.
Mass Spectrom Rev ; 35(1): 188-98, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-25869251

RESUMEN

Contemporary reports by Polish authors on the application of mass spectrometric methods for the elucidation of the subtle molecular structure of biodegradable polymers and their degradation products will be presented. Special emphasis will be given to natural aliphatic (co)polyesters (PHA) and their synthetic analogues, formed through anionic ring-opening polymerization (ROP) of ß-substituted ß-lactones. Moreover, the application of MS techniques for the evaluation of the structure of biodegradable polymers obtained in ionic and coordination polymerization of cyclic ethers and esters as well as products of step-growth polymerization, in which bifunctional or multifunctional monomers react to form oligomers and eventually long chain polymers, will be discussed. Furthermore, the application of modern MS techniques for the assessment of polymer degradation products, frequently bearing characteristic end groups that can be revealed and differentiated by MS, will be discussed within the context of specific degradation pathways. Finally, recent Polish accomplishments in the area of mass spectrometry will be outlined.

12.
Inorg Chem ; 56(3): 1349-1365, 2017 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-28106382

RESUMEN

A family of homo- and heteroleptic zinc complexes bearing aminonaphtholate ligands was synthesized and fully characterized. Using NMR spectroscopy and DFT calculation, bis-alkoxy-bridged complexes [LZn(µ-OR)]2 were confirmed to have dimeric structures in solution, analogous to those obtained via X-ray crystallography. Surprisingly, a detailed experimental and theoretical study of the catalytic activity of [LZn(µ-OR)]2 in the ring-opening polymerization (ROP) of lactides showed that although well-defined alkoxy dimers possess a single-site structural motif, the most active initiator is obtained during in situ alcoholysis of the alkylzinc precursor. These results indicate that rational ancillary and alkoxy ligand design that takes into account its mutual interaction on monomer coordination may be key to the synthesis of new high-performance ROP catalysts.

13.
Int J Mol Sci ; 18(2)2017 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-28157175

RESUMEN

In the past decade, poly-γ-glutamic acid (γ-PGA)-based micro/nanoparticles have garnered remarkable attention as antimicrobial agents and for drug delivery, owing to their controlled and sustained-release properties, low toxicity, as well as biocompatibility with tissue and cells. γ-PGA is a naturally occurring biopolymer produced by several gram-positive bacteria that, due to its biodegradable, non-toxic and non-immunogenic properties, has been used successfully in the medical, food and wastewater industries. Moreover, its carboxylic group on the side chains can offer an attachment point to conjugate antimicrobial and various therapeutic agents, or to chemically modify the solubility of the biopolymer. The unique characteristics of γ-PGA have a promising future for medical and pharmaceutical applications. In the present review, the structure, properties and micro/nanoparticle preparation methods of γ-PGA and its derivatives are covered. Also, we have highlighted the impact of micro/nanoencapsulation or immobilisation of antimicrobial agents and various disease-related drugs on biodegradable γ-PGA micro/nanoparticles.


Asunto(s)
Antiinfecciosos/administración & dosificación , Bacterias/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Nanopartículas/química , Ácido Poliglutámico/análogos & derivados , Animales , Antiinfecciosos/uso terapéutico , Antineoplásicos/administración & dosificación , Materiales Biocompatibles Revestidos/química , Composición de Medicamentos , Técnicas de Transferencia de Gen , Humanos , Hipoglucemiantes/administración & dosificación , Ácido Poliglutámico/química , Solventes , Vacunas/administración & dosificación
14.
Exp Eye Res ; 147: 161-168, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27185162

RESUMEN

High titers of anti-carbonic anhydrase II (anti-CA II) autoantibodies were detected in sera of patients with autoimmune retinopathies (AR), including cancer-associated retinopathy (CAR) and also in normal population. The goal was to investigate whether unique immunodominant epitopes for anti-CAII autoantibodies occur in AR and CAR. A cohort of 216 patients with symptoms of AR and CAR and healthy controls, seropositive for anti-CA II autoantibodies were analyzed for the prevalence of CAII major domains. Autoantibody titers against CAII in sera were determined by ELISA. Biotinylated 12-mer synthetic peptides, overlapping the entire sequence of CAII, were coated onto a microplate and monospecific sera were tested for their ability to bind specific peptides by ELISA. We identified 3 epitopes common for AR, CAR and control subjects but the key epitopes were significantly different between sera from different groups (p = 0.009). Ninety one percent of AR sera predominantly reacted with the N-terminal epitope 85-90 (p < 0.0001), which corresponded to the catalytic core of the enzyme. The major epitope for 77% of CAR autoantibodies was found to be reactive with the peptide 218-222 (P = 0.0005) clustered within the α-helix. The analysis of epitope position in a 3D structure of the native CAII revealed their partial or full exposure on the protein surface. Anti-CAII autoantibodies from normal healthy controls did not share the major determinants with either group of patients. We also observed an epitope shift in antibody recognition from the AR-like epitope profile to the CAR-like profile in a patient who developed cancer 2 years after initial symptoms of vision loss (p < 0.0001). In conclusion, autoantibodies against CAII recognized different epitopes, depending whether they originated in patients with or without cancer. Also, antibodies targeted different determinates within the molecule during the development of retinopathy from non-paraneoplastic to paraneoplastic, suggesting an intramolecular epitope spreading phenomenon. Accurate distinction between AR and CAR is critical in designing immunotherapies and better diagnosis for those two conditions.


Asunto(s)
Autoanticuerpos/sangre , Enfermedades Autoinmunes/inmunología , Anhidrasa Carbónica II/inmunología , Epítopos/inmunología , Síndromes Paraneoplásicos Oculares/inmunología , Enfermedades de la Retina/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Ensayo de Inmunoadsorción Enzimática , Mapeo Epitopo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
15.
Int J Mol Sci ; 17(7)2016 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-27447619

RESUMEN

Polyhydroxyalkanoates (PHAs) are a group of bioplastics that have a wide range of applications. Extensive progress has been made in our understanding of PHAs' biosynthesis, and currently, it is possible to engineer bacterial strains to produce PHAs with desired properties. The substrates for the fermentative production of PHAs are primarily derived from food-based carbon sources, raising concerns over the sustainability of their production in terms of their impact on food prices. This paper gives an overview of the current carbon sources used for PHA production and the methods used to transform these sources into fermentable forms. This allows us to identify the opportunities and restraints linked to future sustainable PHA production. Hemicellulose hydrolysates and crude glycerol are identified as two promising carbon sources for a sustainable production of PHAs. Hemicellulose hydrolysates and crude glycerol can be produced on a large scale during various second generation biofuels' production. An integration of PHA production within a modern biorefinery is therefore proposed to produce biofuels and bioplastics simultaneously. This will create the potential to offset the production cost of biofuels and reduce the overall production cost of PHAs.


Asunto(s)
Bacterias/metabolismo , Carbono/química , Polihidroxialcanoatos/biosíntesis , Biocombustibles , Fermentación , Humanos
16.
Ophthalmology ; 122(9): 1907-16, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26123090

RESUMEN

PURPOSE: To analyze the clinical characteristics of a serous retinopathy associated with mitogen-activated protein kinase kinase (MEK) inhibition with binimetinib treatment for metastatic cutaneous melanoma (CM) and uveal melanoma (UM), and to determine possible pathogenetic mechanisms that may lead to this retinopathy. DESIGN: Prospective observational, cohort-based, cross-sectional study. PARTICIPANTS: Thirty CM patients and 5 UM patients treated with the MEK inhibitor binimetinib (CM) or a combination of binimetinib and the protein kinase C inhibitor sotrastaurin (UM). METHODS: Extensive ophthalmic examination was performed, including Early Treatment of Diabetic Retinopathy Study best-corrected visual acuity, applanation tonometry, slit-lamp examination, indirect ophthalmoscopy, digital color fundus photography, and optical coherence tomography (OCT). In selected cases, additional examinations were performed, including visual field testing and electro-oculography (EOG). Blood samples were obtained from 3 CM patients and 3 UM patients to analyze the presence of autoantibodies against retinal and retinal pigment epithelium (RPE) proteins. MAIN OUTCOME MEASURES: Visual symptoms, visual acuity, fundus appearance, characteristics on OCT, fundus autofluorescence (FAF), and EOG. RESULTS: Six CM patients (20%) and 2 UM patients (40%) reported visual symptoms during the study. The median time to the onset of symptoms, which were all mild and transient, was 3.5 days (range, <1 hour to 3 weeks). On OCT, subretinal fluid (SRF) was detected in 77% of CM patients and 60% of UM patients. In the 26 patients with SRF, the fovea was affected in 85%. After the start of the medication, an EOG was performed in 19 eyes of 11 patients; 16 of these eyes (84%) developed SRF on OCT. Fifteen of these eyes (94%) showed an abnormal Arden ratio (<1.65). A broad pattern of anti-retinal antibodies was found in 3 CM patients and 2 UM patients tested, whereas anti-RPE antibodies were detected in all 6 tested patients. CONCLUSIONS: A time-dependent and reversible serous retinopathy can develop both in patients with metastatic CM and UM treated with binimetinib. A minority of patients develop visual symptoms, which are generally mild and transient. A cause of binimetinib-associated serous retinopathy may be toxicity of medication, but autoantibodies also may be involved.


Asunto(s)
Bencimidazoles/efectos adversos , Coriorretinopatía Serosa Central/inducido químicamente , Melanoma/tratamiento farmacológico , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Neoplasias de la Úvea/tratamiento farmacológico , Adulto , Anciano , Autoanticuerpos/sangre , Bencimidazoles/uso terapéutico , Coriorretinopatía Serosa Central/diagnóstico , Coriorretinopatía Serosa Central/fisiopatología , Estudios Transversales , Combinación de Medicamentos , Electrooculografía , Electrorretinografía , Proteínas del Ojo/inmunología , Femenino , Angiografía con Fluoresceína , Humanos , Masculino , Melanoma/fisiopatología , Persona de Mediana Edad , Estudios Prospectivos , Proteína Quinasa C/antagonistas & inhibidores , Pirroles/uso terapéutico , Quinazolinas/uso terapéutico , Neoplasias Cutáneas , Líquido Subretiniano , Tomografía de Coherencia Óptica , Neoplasias de la Úvea/fisiopatología , Agudeza Visual/fisiología , Melanoma Cutáneo Maligno
17.
Biomacromolecules ; 16(11): 3603-12, 2015 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-26444385

RESUMEN

Conjugates of antioxidants p-anisic (p-AA) and vanillic (VA) acids with nontoxic, biocompatible, and biodegradedable oligo-(R,S)-(3-hydoxybutyrate) carrier were synthesized, and their structural and biological characterization was performed. The molecular structure of the bioconjugates, in which antioxidants are covalently bonded with oligo(3-hydroxybutyrate) (OHB) chains, has been proven by mass spectrometry supported by NMR. The bioconjugate hydrolytic degradation studies allowed gaining thorough insight into the hydrolysis process and confirmed the release of p-AA and VA. In vitro studies demonstrated that all of the conjugates studied were well tolerated by KB and HaCaT cell lines, as they had no marked cytotoxicity, while conjugates with a relatively short OHB carrier are optimal to support keratinocyte function. The preliminary study of the biological activity confirmed the protective effect of VA-OHB conjugates against H2O2-induced lipid peroxidation in human keratinocytes (HaCaT). It was also demonstrated that the selected bioconjugates can penetrate all layers of the skin, which shows their functionality and opens up their potential application in cosmetology.


Asunto(s)
Antioxidantes/farmacología , Cosméticos/química , Sistemas de Liberación de Medicamentos , Ácido 3-Hidroxibutírico/química , Antioxidantes/química , Materiales Biocompatibles , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular , Humanos , Peróxido de Hidrógeno/metabolismo , Hidrólisis , Éteres de Hidroxibenzoatos/química , Éteres de Hidroxibenzoatos/farmacología , Queratinocitos/citología , Queratinocitos/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Estructura Molecular , Piel/citología , Piel/metabolismo , Ácido Vanílico/química , Ácido Vanílico/farmacología
18.
Rapid Commun Mass Spectrom ; 29(6): 533-44, 2015 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-26160419

RESUMEN

RATIONALE: Pesticides are commonly used in agriculture to ensure high crop yield; however, because of their low resistance to environmental conditions, a large amount of pesticides does not reach target pests and becomes an environmental pollutant. One of the ways to reduce these drawbacks is synthesis of polymeric systems, which allows for controlled release of pesticides for a prolonged period of time. Herein we report the synthesis and characterization of novel potentially bioactive (co)oligoesters with bioactive moieties (selected from pesticides) which are covalently linked along an oligoester backbone. METHODS: The delivery systems of pesticides were prepared via anionic ring-opening polymerization of ß-substituted ß-lactones containing bioactive moieties as a pendant group selected from pesticides and their copolymerization with ß-butyrolactone in the presence of carboxylates as initiators. Electrospray ionization multistage mass spectrometry (ESI-MS(n)) supported by (1)H NMR were applied in order to establish the structure, at a molecular level, of the new biodegradable oligomeric release system of selected pesticides. RESULTS: Based on ESI-MS(n) analyses, the structures of the resulting (co)oligoesters were established at the molecular level. The ESI-MS/MS allowed to confirm the structures of end groups and to determine the composition of individual (co)oligoester molecules which contained one, two or three bioactive molecules per (co)oligomer. Additionally, it was shown that fragmentation of selected ions of potentially bioactive (co)oligoesters proceeded via random breakage of ester bonds along the oligomer chain and ester bonds of the bioactive pendant group. CONCLUSIONS: An analytical method for detailed structural characterization at the molecular level of potentially bioactive (co)oligoesters has been developed. These results are important in the analysis of designed biodegradable polymeric controlled-release systems of pesticides with potential agricultural applications.


Asunto(s)
Plaguicidas/química , Ésteres/química , Estructura Molecular , Plaguicidas/síntesis química , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem
19.
BMC Ophthalmol ; 14: 154, 2014 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-25488058

RESUMEN

BACKGROUND: Age-related macular degeneration (AMD) is the leading cause of central vision loss in older adults. Anti-retinal autoantibodies (AAbs) have been found in individuals with AMD. The goal of the study was to determine the AAb specificity in different stages of AMD, and determine whether there is a prevalent AAb signature. METHODS: Sera of 134 participants in the Age-related Eye Disease Study were analyzed for anti-retinal AAbs by western blotting. The subjects were classified by diagnostic subgroups based upon their clinical classification: No AMD, Intermediate AMD, and Late AMD - geographic atrophy (GA) and Late AMD - neovascular (NV). RESULTS: The presence of anti-retinal AAb was detected in 58% patients with Intermediate and Late AMD, and 54% of those with no AMD. AAbs bound to fifteen different retinal antigens. Most individuals had 1 specific AAbs (67%), with the remainder having 2 to 4 different AAbs. Over 40% of patients with Intermediate AMD, and 46% of those with GA had anti-enolase AAbs, compared with 29% of individuals with NV and 29% with no AMD. Different AAbs signatures related to NV as compared to GA and/or Intermediate AMD were distinguished. Anti-40-kDa (10%) and 42-kDa (16%) autoantibodies were associated with Intermediate AMD, while anti-30-kDa AAbs (23%) were primarily present in GA. Anti-32-kDa (12%), 35-kDa (21%), and 60-kDa (8%) AAbs were more frequent in NV AMD. CONCLUSIONS: A unique AAb pattern for each of the disease subgroups was present when AMD progressed from the intermediate to the late forms of severity. Differences in the frequency of specific AAbs between AMD subgroups suggested that they may participate in pathogenicity of AMD. Further studies are necessary to confirm these observations in the larger cohort and individual AMD patients over time.


Asunto(s)
Autoanticuerpos/sangre , Autoantígenos/inmunología , Atrofia Geográfica/inmunología , Retina/inmunología , Degeneración Macular Húmeda/clasificación , Degeneración Macular Húmeda/inmunología , Anciano , Artritis/inmunología , Biomarcadores/sangre , Western Blotting , Femenino , Atrofia Geográfica/clasificación , Humanos , Masculino , Prevalencia , Fumar/inmunología
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