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1.
Small ; 20(22): e2307536, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38126666

RESUMEN

Poly (3,4-ethylenedioxythiophene) (PEDOT) doped with polystyrene sulfonate (PSS) is the most used conducting polymer from energy to biomedical applications. Despite its exceptional properties, there is a need for developing new materials that can improve some of its inherent limitations, e.g., biocompatibility. In this context, doping PEDOT is propose with a robust recombinant protein with tunable properties, the consensus tetratricopeptide repeated protein (CTPR). The doping consists of an oxidative polymerization, where the PEDOT chains are stabilized by the negative charges of the CTPR protein. CTPR proteins are evaluated with three different lengths (3, 10, and 20 identical CTPR units) and optimized varied synthetic conditions. These findings revealed higher doping rate and oxidized state of the PEDOT chains when doped with the smallest scaffold (CTPR3). These PEDOT:CTPR hybrids possess ionic and electronic conductivity. Notably, PEDOT:CTPR3 displayed an electronic conductivity of 0.016 S cm-1, higher than any other reported protein-doped PEDOT. This result places PEDOT:CTPR3 at the level of PEDOT-biopolymer hybrids, and brings it closer in performance to PEDOT:PSS gold standard. Furthermore, PEDOT:CTPR3 dispersion is successfully optimized for inkjet printing, preserving its electroactivity properties after printing. This approach opens the door to the use of these novel hybrids for bioelectronics.


Asunto(s)
Materiales Biocompatibles , Compuestos Bicíclicos Heterocíclicos con Puentes , Conductividad Eléctrica , Polímeros , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Polímeros/química , Materiales Biocompatibles/química , Poliestirenos/química , Ingeniería de Proteínas/métodos , Iones , Electrónica
2.
Pediatr Res ; 94(3): 956-964, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37059899

RESUMEN

BACKGROUND: There is extensive evidence that Holder pasteurization (HoP) (30 min at 62.5 °C) has harmful effects on the bioactivities of human milk (HM). We previously demonstrated that lowering HoP temperature is sufficient to inactivate Cytomegalovirus (HCMV). Here, we analyzed the effect of lowering time/temperature on the antiviral activity against HCMV and IgA levels of HM. METHODS: Eighty HM samples from five mothers were pasteurized in a range of temperature (62.5-56 °C) and time (40-10 min) in a conventional setting of Human Milk Bank. Unpasteurized HM from each mother was used as control. The samples were assayed against HCMV-AD169 strain in cell cultures and IgA levels were determined by ELISA. RESULTS: All HM samples exhibited anti-HCMV activity, to a different extent. An improvement of antiviral activity was observed in samples treated at 60, 58 and 56 °C compared to those at 62.5 °C, with ID50 values near those of unpasteurized milk. Similarly, better retention in IgA levels was observed by reducing the temperature of treatment. CONCLUSIONS: We demonstrated that a 2.5 °C reduction of heat treatment significantly preserved the IgA content and fully restored the anti-HCMV activity of HM, supporting this variant of HoP as a valid alternative to preserve HM bioactivities. IMPACT: This work questions the standard HoP and opens the debate on whether the pasteurization temperature commonly used in Human Milk Banks should be lowered to better preserve the biological components of the milk. A reduction of HoP temperature at 60 °C determined a significant preservation of anti-HCMV activity and IgA content of donor HM, compared to standard HoP. This alternative HoP is highly feasible compared to other substitute pasteurization techniques, since it would employ the same pasteurizer equipment found in most Human Milk Banks.


Asunto(s)
Bancos de Leche Humana , Leche Humana , Humanos , Temperatura , Pasteurización/métodos , Inmunoglobulina A , Antivirales/farmacología
3.
Arch Gynecol Obstet ; 306(4): 1085-1100, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35551456

RESUMEN

PURPOSE: The HPV-Quality-of-Life (HPV-QoL) questionnaire was developed to determine the impact of Human-Papillomavirus (HPV) infection and related interventions on women health-related quality-of-life. This study provides the development and preliminary psychometric properties of a novel HPV-QoL questionnaire for adult women with HPV. METHODS: After reviewing literature and cognitive debriefing interviews in women who had experienced HPV-related conditions, instrument items and domains were developed. A draft questionnaire was pilot tested for comprehension and ease of completion. Psychometric evaluation of the final HPV-QoL scale was conducted in a psychometric study including 252 adult women derived to our centre by a positive HPV test in the cervical cancer screening program and/or presenting genital warts. RESULTS: The present study reveals that the HPV-QoL questionnaire, structured in four domains: general well-being [including psychological well-being and social well-being subdomains], health, contagiousness and sexuality, showed good metric properties of feasibility irrespective of age or educational level, and time to administer was less than 5 min. Internal consistency and temporal stability (reliability) showed values above the acceptable standards. The instrument showed its concurrent validity by means of a significant correlation with mental and sexual existing instruments; GHQ-12 and FSFI questionnaires, respectively, and also known groups validity showing significant differences among the subgroups regarding either sexual dysfunction or mental deterioration. CONCLUSION: This study provides an HPV-QoL questionnaire with an innovative patient-reported outcomes specific measurement tool to assess HRQoL in women with HPV infection. The present study suggests this questionnaire has satisfactory psychometric properties, including validity and reliability. Results support the use of the HPV-QoL questionnaire as a HRQoL measurement instrument for daily medical practice and clinical research.


Asunto(s)
Alphapapillomavirus , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Adulto , Detección Precoz del Cáncer , Femenino , Humanos , Papillomaviridae , Infecciones por Papillomavirus/diagnóstico , Psicometría , Calidad de Vida , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Neoplasias del Cuello Uterino/psicología
4.
Int J Mol Sci ; 23(14)2022 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-35887008

RESUMEN

Gingival regeneration aims at restoring the architecture and functionality of oral damaged tissue. Different biomaterials or biological materials have been tested for tissue repair, such as platelet concentrates such as PL. In this article, the use of extracellular vesicles (EVs) derived from platelet lysate (PL) and their combination with hyaluronic acid biomaterials (HA) in an in vitro wound healing assay is investigated. EVs were isolated by size exclusion chromatography from PL. In addition, HA gels were formulated with PL or EVs. EVs or HA combined with EVs (HA-EVs) were tested in vitro in gingival fibroblasts and keratinocytes for biocompatibility (LDH activity and metabolic activity) and by an in vitro wound-healing assay and gene expression analysis. EVs and EVs-HA treatments were biocompatible in gingival fibroblasts and keratinocytes and showed an increase in wound healing in vitro compared to control. Moreover, changes in gene expression related to extracellular matrix remodeling were observed after the treatment with EVs. EVs can be combined with HA biomaterials, showing good biocompatibility and preserving their activity and functionality. Therefore, platelet-derived EVs could emerge as a new application for periodontal regeneration in combination with biomaterials in order to enhance their clinical use.


Asunto(s)
Vesículas Extracelulares , Encía , Materiales Biocompatibles/metabolismo , Vesículas Extracelulares/metabolismo , Fibroblastos , Queratinocitos
5.
Eur J Pediatr ; 180(1): 291-294, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32653937

RESUMEN

Oral immunotherapy is a common treatment in cow's milk protein allergy. The Department of Pediatric Allergology at the Children's Hospital of Zaragoza performed a retrospective analysis of 335 infants under 1 year of age diagnosed with IgE-mediated cow's milk and early treated. Clinical evaluation, skin prick test, and serum-specific IgE level control were performed before starting and after finishing treatment. Upon completion of treatment, more than 98% of patients became tolerant to milk and no one presented serious adverse reactions. Nowadays, the remaining non-tolerant patients (1.8%) can take milk or derivatives daily-as prophylaxis-to a certain maximum dose and still remain asymptomatic. After immunotherapy, both positive skin prick tests and a progressive decrease in specific IgE levels were found, as desensitization to milk increased.Conclusion: Oral immunotherapy is a safe and effective treatment against allergy to cow's milk proteins in infants. Such treatment should be offered to the children's families from the first moment of diagnosis. What is known: • Cow's milk proteins are responsible for the earliest IgE-mediated allergic reactions in children. • Oral immunotherapy (OIT) is commonly used as cow's milk allergy treatment and it is proposed at different ages. What is new: • OIT it is an effective and safe method with no severe reactions at early ages. • The number of reaching successful treatments is awesome so we believe that immunity response can be molded at the first months of life, so the probability of success with infants is greater than in older children.


Asunto(s)
Hipersensibilidad a la Leche , Animales , Bovinos , Niño , Femenino , Humanos , Inmunoglobulina E , Inmunoterapia , Lactante , Hipersensibilidad a la Leche/diagnóstico , Hipersensibilidad a la Leche/terapia , Proteínas de la Leche , Estudios Retrospectivos , Pruebas Cutáneas
6.
Childs Nerv Syst ; 37(12): 3817-3826, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34319438

RESUMEN

BACKGROUND: Stereo-electroencephalography (SEEG) is a well-known invasive diagnostic method for drug-resistant epilepsy (DRE). Its rate of complications is relatively low, being the intracranial hemorrhage (ICH) the most relevant. Most centers perform immediate imaging studies after SEEG to rule out complications. However, delayed intracranial hemorrhages (DIH) can occur despite normal imaging studies in the immediate postoperative period. METHODS: We performed a retrospective review of DRE pediatric patients operated on SEEG between April 2016 and December 2020 in our institution. After implantation, an immediate postoperative CT was performed to check electrode placement and rule out acute complications. An additional MRI was performed 24 h after surgery. We collected all postoperative hemorrhages and considered them as major or minor according to Wellmer´s classification. RESULTS: Overall, 25 DRE patients were operated on SEEG with 316 electrodes implanted. Three ICHs were diagnosed on postoperative imaging. Two of them were asymptomatic requiring no treatment, while the other needed surgical evacuation after clinical worsening. The total risk of hemorrhage per procedure was 12%, but just one third of them were clinically relevant. Two hemorrhages were not visible on immediate postoperative CT, being incidentally diagnosed in the 24 h MRI. We recorded them as DIH and are reported in detail. CONCLUSION: Few reports of DIH after SEEG exist in the literature. It remains unclear whether these cases are late occurring hemorrhages or immediate postoperative hemorrhages undiagnosed on initial imaging. According to our findings, we recommend to perform additional late postoperative imaging to diagnose these cases and manage them accurately.


Asunto(s)
Diagnóstico Tardío , Epilepsia Refractaria , Niño , Epilepsia Refractaria/cirugía , Electrodos Implantados , Electroencefalografía , Humanos , Hemorragias Intracraneales/diagnóstico por imagen , Hemorragias Intracraneales/etiología , Estudios Retrospectivos , Técnicas Estereotáxicas
7.
J Nematol ; 532021.
Artículo en Inglés | MEDLINE | ID: mdl-34957410

RESUMEN

Entomopathogenic nematodes (EPN) are excellent biocontrol agents against various insect pests. Novel biotechnological approaches can enhance their utility against insects above-ground, opening a new venue for selecting superior EPN against certain insects. We hypothesize that different populations of the same species but from different origins (habitat, ecoregion) will differ in their virulence. This study aimed to evaluate the virulence of various EPN populations against two pests of worldwide incidence and damage to high value crops: Frankliniella occidentalis (Thysanoptera: Thripidae) and Tuta absoluta (Lepidoptera: Gelechiidae). We tested 10 EPN populations belonging to three EPN species: Heterorhabditis bacteriophora (Koppert, MG-618b, AM-203, RM-102), Steinernema feltiae (Koppert, RS-5, AM-25, RM-107), and Steinernema carpocapsae (Koppert, MG-596a). Each EPN population was tested at two concentrations. Frankliniella occidentalis was tested at 160 and 80 IJs/cm2 and T. absoluta at 21 and 4 IJs/cm2. Control treatments followed the same experimental procedure but only adding distilled water. Overall, whenever different, higher IJs concentration resulted in lower adult emergence, higher larval mortality, and shorter time to kill the insects. Considering the low concentration, S. feltiae provided the best results for both insects and instars investigated, while H. bacteriophora and S. carpocapsae required a high concentration to reach similar or slightly better results. Differences among populations of each of the species were detected, but only the native populations of H. bacteriophora populations showed consistently higher control values against both insects/instar compared with the commercial one. Differences among S. feltiae and S. carpocapsae populations depended on the IJs concentration, insect, and instar. We consider S. feltiae a very promising species for their application against F. occidentalis and T. absoluta, with the Koppert population as the most consistent among the populations tested. Specific EPN-populations of S. carpocapsae and H. bacteriophora were good candidates against certain instar/insects at high concentrations. This study emphasized the importance of intraspecific variability for EPN virulence.

8.
J Pediatr Gastroenterol Nutr ; 70(6): 864-867, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32443049

RESUMEN

Nonthermal methods are more efficient at preserving various biological properties of human milk, as compared with holder pasteurization (HoP), which is the most common preservation method. This study was performed to assess the effects of nonthermal processing on bactericidal activity against Escherichia coli in human milk. Milk samples obtained from the Regional Human Milk Bank in Warsaw at Holy Family Hospital were processed by HoP, irradiated with ultraviolet-C (UV-C) for 5, 10, and 15 minutes (6720 J/L each minute), subjected to 2 variations of high-pressure processing (HPP): 450 MPa for 15 minutes and 200 MPa for 10 minutes + 400 MPa for 10 min, with a 10-minutes break. The samples were then evaluated by a bactericidal assay (raw untreated human milk was used as a control). The bactericidal capacity after HoP was preserved in 12.1% of samples, showing a significant reduction in bactericidal properties compared with in raw milk (P < 0.05). The differences between samples preserved by nonthermal methods and raw milk were not significant (P > 0.05). Nonthermal methods of human milk treatment better preserve the bactericidal capacity compared with holder pasteurisation. Those alternative technologies to HoP can be proposed after further investigation for milk processing for Human Milk Banks facilities.


Asunto(s)
Bancos de Leche Humana , Leche Humana , Antibacterianos/farmacología , Escherichia coli , Humanos , Pasteurización
9.
Childs Nerv Syst ; 36(7): 1557-1561, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31950248

RESUMEN

Multinodular and vacuolating neuronal tumor (MVNT) is a rare newly identified benign lesion, firstly included in the World Health Organization classification of tumors of the central nervous system in 2016, whose neoplastic or dysplastic nature remains unclear but with a distinctive cytoarchitectural pattern and radiological features. It is usually discovered as late-onset refractory epilepsy, headache related, or an incidental lesion of adulthood. As it is typically a stable disease, many opt for follow-up, as long as it keeps remaining asymptomatic, leaving surgery for refractory epilepsy, neurological deficits, or intracranial hypertension symptoms. A subtotal or complete resection seems to control seizures and neurological manifestations. We herein present the case of a child with refractory epilepsy related to MVNT and focal cortical dysplasia, a dual pathology case in a less frequent age group and without the typical radiological imaging. We report its radiologic features, histologic description, and management, and we present a brief literature review on MVNT focusing on the pediatric cases reported. MVNT should now be another probable low-grade epilepsy-associated lesion (LEAT) in patients of all ages, with a benign and stable course as it constitutes a curable cause of focal epilepsy. As all the refractory cases, surgery should be indicated after a comprehensive evaluation of a multidisciplinary epilepsy surgery team.


Asunto(s)
Neoplasias Encefálicas , Epilepsia Refractaria , Malformaciones del Desarrollo Cortical , Niño , Epilepsia Refractaria/diagnóstico por imagen , Epilepsia Refractaria/etiología , Epilepsia Refractaria/cirugía , Humanos , Imagen por Resonancia Magnética , Malformaciones del Desarrollo Cortical/complicaciones , Malformaciones del Desarrollo Cortical/diagnóstico por imagen , Malformaciones del Desarrollo Cortical/cirugía , Convulsiones
10.
Bioconjug Chem ; 30(1): 242-252, 2019 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-30566340

RESUMEN

This work aims at learning how the size of gold nanocarriers influences the transport of DNA-alkylating antitumoral drugs. For this purpose, we devised conjugates of mercaptoethylmitomycin C (MEMC), a DNA alkylating agent, with gold nanoparticles of different sizes (2, 5, and 14 nm), and studied how size affects drug cytotoxicity, tumor penetrability, cellular uptake, and intracellular localization using two-dimensional (2D) and three-dimensional (3D) cell models. We show that only small, 2 nm, nanoparticles can transport MEMC efficiently to the cell nucleus, whereas MEMC cell uptake is much lower when delivered by these small nanoparticles than with the larger ones. 3D cellular models showed that smaller nanoparticles can transport MEMC toward deeper areas of tumor spheroids as compared to larger nanoparticles. We discuss the insights of this work toward the efficient delivery of DNA-targeting drugs.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Oro/química , Nanopartículas del Metal/química , Mitomicina/farmacología , Antibióticos Antineoplásicos/farmacocinética , Transporte Biológico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Mitomicina/farmacocinética , Tamaño de la Partícula
11.
Biochemistry ; 57(8): 1338-1348, 2018 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-29360348

RESUMEN

Thiolases catalyze the condensation of acyl-CoA thioesters through the Claisen condensation reaction. The best described enzymes usually yield linear condensation products. Using a combined computational/experimental approach, and guided by structural information, we have studied the potential of thiolases to synthesize branched compounds. We have identified a bulky residue located at the active site that blocks proper accommodation of substrates longer than acetyl-CoA. Amino acid replacements at such a position exert effects on the activity and product selectivity of the enzymes that are highly dependent on a protein scaffold. Among the set of five thiolases studied, Erg10 thiolase from Saccharomyces cerevisiae showed no acetyl-CoA/butyryl-CoA branched condensation activity, but variants at position F293 resulted the most active and selective biocatalysts for this reaction. This is the first time that a thiolase has been engineered to synthesize branched compounds. These novel enzymes enrich the toolbox of combinatorial (bio)chemistry, paving the way for manufacturing a variety of α-substituted synthons. As a proof of concept, we have engineered Clostridium's 1-butanol pathway to obtain 2-ethyl-1-butanol, an alcohol that is interesting as a branched model compound.


Asunto(s)
Acetil-CoA C-Acetiltransferasa/metabolismo , Acilcoenzima A/metabolismo , Hexanoles/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Acetil-CoA C-Acetiltransferasa/química , Acetil-CoA C-Acetiltransferasa/genética , Dominio Catalítico , Redes y Vías Metabólicas , Modelos Moleculares , Ingeniería de Proteínas/métodos , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética
12.
J Mater Sci Mater Med ; 29(7): 103, 2018 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-29956013

RESUMEN

Osteoinductive capacity of demineralized bone matrix (DBM) is sometimes insufficient or shows high variability between different batches of DBM. Here, we tried to improve its osteoinductive activity by alkali-urea or trypsin treatment but this strategy was unsuccessful. Then, we tested the enrichment of DBM with a bone protein extract (BPE) containing osteogenic growth factors comparing two sources: cortical bone powder and DBM. The osteoinductive capacity (alkaline phosphatase activity) of the obtained BPEs was evaluated in vitro in C2C12 cells. Specific protein levels present in the different BPE was determined by enzyme-linked immunosorbent assay or by a multiplex assay. BPE from cortical bone powder showed a lack of osteoinductive effect, in agreement with the low content on osteoinductive factors. In contrast, BPE from DBM showed osteoinductive activity but also high variability among donors. Thus, we decided to enrich DBM with BPE obtained from a pool of DBM from different donors. Following this strategy, we achieved increased osteoinductive activity and lower variability among donors. In conclusion, the use of a BPE obtained from a pool of demineralized bone to enrich DBM could be used to increase its osteoinductive effect and normalize the differences between donors.


Asunto(s)
Matriz Ósea/patología , Sustitutos de Huesos/química , Huesos/patología , Fosfatasa Alcalina/metabolismo , Animales , Materiales Biocompatibles/metabolismo , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Péptidos y Proteínas de Señalización Intercelular/metabolismo , L-Lactato Deshidrogenasa/metabolismo , Ensayo de Materiales , Ratones , Osteogénesis , Polvos , Tripsina/química
13.
Surg Technol Int ; 332018 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-29985519

RESUMEN

INTRODUCTION: Bowel reconstruction techniques after right hemicolectomy has currently been objective of review, due to the high rate of anastomotic leak. The aim of this study is to analyse our results of the mechanical reinforced terminolateral ileo-transverse anastomosis. MATERIALS AND METHODS: A prospective and descriptive study of a consecutive series of right colonic cancer cases that underwent right hemicolectomy. Mechanical reinforced terminolateral ileo-transverse anastomosis technique was carried out in all patients. Demographics, emergency or elective surgery, surgical management, postoperative complications, rate of anastomotic leak, need for surgical procedure after complication, average stay, and mortality were analysed. RESULTS: A total of 452 patients underwent surgery between 2010 and 2017. Of those, 40.6% were female and 59.4% were male. The average age and body mass index (BMI) was 72±11.3 years old, and 26±7.1, respectively. Elective surgery was carried out in 405 (89.6%) patients. Laparoscopic approach was used in 250 patients (61.7%) and 6% needed conversion. Only 41 patients (10.6%) had major complications (Clavien-Dindo III-IV). The rate of postoperative paralytic ileus reach was up to 13.9%. Reintervention was needed in five patients (1.1%) due to anastomotic leak and three (0.7%) of them from the elective surgery subgroup. There were 10 patients (2.2%) with postoperative gastrointestinal bleeding. The average stay was 8.2±2.8 days and late postoperative mortality in the first 30 days was 2%. CONCLUSIONS: Mechanical reinforced terminolateral ileo-colic anastomosis is a safe technique with a low anastomotic leak rate. Although our results using this approach seem promising, postoperative paralytic ileus is still a high-rate complication.

14.
Molecules ; 23(2)2018 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-29425157

RESUMEN

Nectandra grandiflora Nees (Lauraceae) is a Brazilian native tree recognized by its durable wood and the antioxidant compounds of its leaves. Taking into account that the forest industry offers the opportunity to recover active compounds from its residues and by-products, this study identifies and underlines the potential of natural products from Nectandra grandiflora that can add value to the forest exploitation. This study shows the effect of three different extraction methods: conventional (CE), ultrasound-assisted (UAE) and microwave-assisted (MAE) on Nectandra grandiflora leaf extracts (NGLE) chemical yields, phenolic and flavonoid composition, physical characteristics as well as antioxidant and antifungal properties. Results indicate that CE achieves the highest extraction phytochemical yield (22.16%), but with similar chemical composition to that obtained by UAE and MAE. Moreover, CE also provided a superior thermal stability of NGLE. The phenolic composition of NGLE was confirmed firstly, by colorimetric assays and infrared spectra and then by chromatographic analysis, in which quercetin-3-O-rhamnoside was detected as the major compound (57.75-65.14%). Furthermore, the antioxidant capacity of the NGLE was not altered by the extraction methods, finding a high radical inhibition in all NGLE (>80% at 2 mg/mL). Regarding the antifungal activity, there was observed that NGLE possess effective bioactive compounds, which inhibit the Aspergillus niger growth.


Asunto(s)
Antifúngicos/química , Antioxidantes/química , Flavonoides/química , Fenoles/química , Fitoquímicos/química , Extractos Vegetales/química , Streptophyta/química , Antifúngicos/farmacología , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Aspergillus niger/efectos de los fármacos , Fraccionamiento Químico , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Humanos , Fenoles/aislamiento & purificación , Fenoles/farmacología , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Hojas de la Planta/química , Solubilidad
15.
Anal Chem ; 87(1): 431-40, 2015 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-25411795

RESUMEN

Due to their electrical conductivity and optical transparency, slides coated with a thin layer of indium tin oxide (ITO) are the standard substrate for protein imaging mass spectrometry on tissue samples by MALDI-TOF MS. We have now studied the rf magnetron sputtering deposition parameters to prepare ITO thin films on glass substrates with the required nanometric surface structure for their use in the matrix-free imaging of metabolites and small-molecule drugs, without affecting the transparency required for classical histology. The custom-made surfaces were characterized by atomic force microscopy, scanning electron microscopy, ellipsometry, UV, and laser desorption ionization MS (LDI-MS) and employed for the LDI-MS-based analysis of glycans and druglike molecules, the quantification of lactose in milk by isotopic dilution, and metabolite imaging on mouse brain tissue samples.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Metabolómica , Nanoestructuras/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Compuestos de Estaño/química , Animales , Encéfalo/metabolismo , Humanos , Marcaje Isotópico , Lactosa/análisis , Rayos Láser , Ratones , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Leche/química , Preparaciones Farmacéuticas/análisis , Espectroscopía de Fotoelectrones , Polisacáridos/análisis
16.
Anal Chem ; 87(22): 11460-7, 2015 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-26482441

RESUMEN

Methods for the absolute quantification of glycans are needed in glycoproteomics, during development and production of biopharmaceuticals and for the clinical analysis of glycan disease markers. Here we present a strategy for the chemo-enzymatic synthesis of (13)C labeled N-glycan libraries and provide an example for their use as internal standards in the profiling and absolute quantification of mAb glycans by matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry. A synthetic biantennary glycan precursor was (13)C-labeled on all four amino sugar residues and enzymatically derivatized to produce a library of 15 glycan isotopologues with a mass increment of 8 Da over the natural products. Asymmetrically elongated glycans were accessible by performing enzymatic reactions on partially protected UV-absorbing intermediates, subsequent fractionation by preparative HPLC, and final hydrogenation. Using a preformulated mixture of eight internal standards, we quantified the glycans in a monoclonal therapeutic antibody with excellent precision and speed.


Asunto(s)
Espectrometría de Masas/métodos , Polisacáridos/análisis , Polisacáridos/biosíntesis , Isótopos de Carbono , Polisacáridos/síntesis química , Polisacáridos/química , Estándares de Referencia
17.
Bioconjug Chem ; 26(4): 755-65, 2015 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-25734507

RESUMEN

The third variable region (V3 peptide) of the HIV-1 gp120 is a major immunogenic domain of HIV-1. Controlling the formation of the immunologically active conformation is a crucial step to the rational design of fully synthetic candidate vaccines. Herein, we present the modulation and stabilization of either the α-helix or ß-strand conformation of the V3 peptide by conjugation to negatively charged gold glyconanoparticles (GNPs). The formation of the secondary structure can be triggered by the variation of the buffer concentration and/or pH as indicated by circular dichoism. The peptide on the GNPs shows increased stability toward peptidase degradation as compared to the free peptide. Moreover, only the V3ß-GNPs bind to the anti-V3 human broadly neutralizing mAb 447-52D as demonstrated by surface plasmon resonance (SPR). The strong binding of V3ß-GNPs to the 447-52D mAb was the starting point to address its study as immunogen. V3ß-GNPs elicit antibodies in rabbits that recognize a recombinant gp120 and the serum displayed low but consistent neutralizing activity. These results open up the way for the design of new fully synthetic HIV vaccine candidates.


Asunto(s)
Vacunas contra el SIDA/química , Anticuerpos Antivirales/biosíntesis , Proteína gp120 de Envoltorio del VIH/inmunología , Infecciones por VIH/prevención & control , VIH-1/inmunología , Inmunoconjugados/química , Nanopartículas/química , Vacunas contra el SIDA/administración & dosificación , Vacunas contra el SIDA/biosíntesis , Vacunas contra el SIDA/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/química , Anticuerpos Neutralizantes/química , Femenino , Oro/química , Proteína gp120 de Envoltorio del VIH/agonistas , Proteína gp120 de Envoltorio del VIH/química , Infecciones por VIH/inmunología , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Pruebas de Neutralización , Estabilidad Proteica , Estructura Secundaria de Proteína , Conejos , Electricidad Estática , Vacunas Sintéticas
19.
Analyst ; 139(11): 2873-83, 2014 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-24737011

RESUMEN

Weathering steel has been employed for the first time to prepare sample plates for matrix-free laser desorption ionisation mass spectrometry (LDI-MS) of small molecules up to a mass range of around 1500 Da. The effective UV absorption, heat conductivity and porosity of the nanostructured inner rust layer formed during passivation determine the excellent performance in LDI-MS for a broad range of different analyte classes. The inexpensive material was evaluated in a series of relevant analytical applications ranging from the matrix-free detection of serum metabolites, lactose quantification, lipid analysis in milk to the glycoprofiling of antibodies and imaging mass spectrometry of brain tissue samples.


Asunto(s)
Nanoestructuras , Preparaciones Farmacéuticas/análisis , Polisacáridos/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Acero , Humanos , Preparaciones Farmacéuticas/sangre , Polisacáridos/sangre , Espectrofotometría Ultravioleta
20.
J Oral Pathol Med ; 43(5): 371-7, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24450511

RESUMEN

OBJECTIVES: To analyze whether oxidative stress (OS) changes are present in patients with bisphosphonate-related osteonecrosis of the jaw (BRONJ) versus controls. MATERIALS AND METHODS: Oxidative stress was analyzed in serum and unstimulated saliva of three groups: Group 1 consisted of 24 patients who had been treated with intravenous bisphosphonates (ivBPs) and developed BRONJ, group 2 consisted of 20 patients who had received ivBPs and did not develop BRONJ, and group 3 comprised 17 control subjects. Reduced glutathione (GSH), malondialdehyde (MDA), oxidized glutathione (GSSG), and 8-oxo-7,8-dihydro-2-deoxyguanosine (8-oxo-dG) levels, as well as the GSSG/GSH ratio, were measured. RESULTS: Mean serum and saliva levels of MDA, GSSG, and 8-oxo-dG and the GSSG/GSH ratio were significantly higher in patients with BRONJ than in controls. We found no significant difference in OS according to BRONJ stage, sex, or location in the jaws. Logistic regression analysis revealed that the GSSG/GSH ratio was a significant factor predicting the development of BRONJ (P = 0.01). CONCLUSIONS: Oxidative stress was detected in patients with BRONJ, and the GSSG/GSH ratio was the most significant OS variable found; it was a significant factor predicting the development of BRONJ.


Asunto(s)
Osteonecrosis de los Maxilares Asociada a Difosfonatos/metabolismo , Estrés Oxidativo/fisiología , 8-Hidroxi-2'-Desoxicoguanosina , Administración Intravenosa , Corticoesteroides/uso terapéutico , Anciano , Antineoplásicos/administración & dosificación , Biomarcadores/análisis , Biomarcadores/sangre , Osteonecrosis de los Maxilares Asociada a Difosfonatos/sangre , Neoplasias de la Mama/tratamiento farmacológico , Estudios de Casos y Controles , Índice CPO , Índice de Placa Dental , Desoxiguanosina/análogos & derivados , Desoxiguanosina/análisis , Desoxiguanosina/sangre , Difosfonatos/administración & dosificación , Femenino , Glutatión/análisis , Glutatión/sangre , Disulfuro de Glutatión/análisis , Disulfuro de Glutatión/sangre , Humanos , Masculino , Malondialdehído/análisis , Malondialdehído/sangre , Persona de Mediana Edad , Mieloma Múltiple/tratamiento farmacológico , Índice de Higiene Oral , Saliva/química , Factores Sexuales
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