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1.
Bioresour Technol ; 394: 130234, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38142906

RESUMEN

A new alternative for hydrodynamic cavitation-assisted pretreatment of sugarcane bagasse was proposed, along with a simultaneous saccharification and co-fermentation (SSCF) process performed in interconnected columns. Influential variables in the pretreatment were evaluated using a statistical design, indicating that an ozone flow rate of 10 mg min-1 and a pH of 5.10 resulted in 86 % and 72 % glucan and xylan hydrolysis yields, respectively, in the subsequent enzymatic hydrolysis process. Under these optimized conditions, iron sulfate (15 mg L-1) was added to assess Fenton pretreatment, resulting in glucan and xylan hydrolysis yields of 92 % and 71 %, respectively, in a material pretreated for 10 min. In SSCF, ethanol volumetric productivities of 0.33 g L-1 h-1 and of 0.54 g L-1 h-1 were obtained in batch and fed-batch operation modes, achieving 26 g L-1 of ethanol in 48 h in the latter mode.


Asunto(s)
Celulosa , Saccharomycetales , Saccharum , Celulosa/metabolismo , Fermentación , Saccharum/metabolismo , Etanol , Hidrodinámica , Células Inmovilizadas/metabolismo , Xilanos , Hidrólisis
2.
Braz J Med Biol Res ; 56: e12682, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37493770

RESUMEN

Preventing the replication of adenovirus could have practical uses, such as controlling infection with wild-type virus or in applications involving recombinant vectors. Mainly transient methods have been used to inhibit adenovirus replication, including siRNA or drugs. Here, we tested whether stable expression of shRNA designed to target hexon, Iva2, or pol can inhibit the replication of a recombinant adenoviral vector, Ad-LacZ (serotype 5, E1/E3 deleted), in 293T cells. Significant knockdown correlating with reduced Ad-LacZ replication was achieved only when hexon was targeted. Cell sorting and isolation of cellular clones further accentuated knockdown of the hexon transcript, reduced protein levels by more than 90%, and diminished adenovirus production. As visualized by transmission electron microscopy, the cellular clone expressing the hexon-specific shRNA yielded 89.2% fewer particles compared to the parental 293T cells. Full scale production followed by purification revealed a 90.2% reduction in Ad-LacZ biological titer. These results support the notion that stable expression of shRNA can be used as a means to control adenovirus replication.


Asunto(s)
Adenoviridae , Replicación Viral , Adenoviridae/genética , ARN Interferente Pequeño/genética , Vectores Genéticos/genética , Humanos , Células HEK293 , Transcripción Genética , Células Clonales
3.
Rehabilitación (Madr., Ed. impr.) ; 57(2): [100750], Abr-Jun 2023. tab
Artículo en Inglés | IBECS | ID: ibc-218561

RESUMEN

Introduction and objectives: Chronic low back pain is the main cause of disability worldwide, generating high costs for society. To evaluate the prevalence of disability in patients with non-specific chronic low back pain and associated factors, including the impacts of low back pain and psychosocial factors linked to kinesiophobia, catastrophism, anxiety, and depression. Patients: A cross-sectional study was carried out with 108 adult individuals who had non-specific chronic low back pain. The patients answered previously validated questionnaires, namely the Brief Pain Inventory, the Roland-Morris Disability Questionnaire, the Pain Catastrophizing Scale, the Tampa Kinesiophobia Scale, and the Hospital Anxiety and Depression Scale. Results: The prevalence of disability observed was 65.7%, with the mean disability score being 15.7±5.3 points in the Roland-Morris Disability Questionnaire. Although pain intensity and other domains of the Brief Pain Inventory, like anxiety, depression, and severe kinesiophobia were significant in the bivariate analyses, they were not associated with disability in the multivariate analysis. Only catastrophic thoughts (prevalence ratio [PR]=1.19; 95% confidence interval [CI]: 1.07–1.32), and the ‘walking’ domain (PR=1.08; 95% CI: 1.03–1.14) remained statistically associated with disability. Conclusion: Pain catastrophization and impact on gait were associated with disability in individuals with non-specific chronic low back pain. Motor control thoughts and behaviors during functional activities were considered to be relevant aspects for the better assessment and treatment of these patients.(AU)


Introducción y objetivos: La lumbalgia crónica es la principal causa de discapacidad a nivel mundial, generando altos costos para la sociedad. Evaluar la prevalencia de discapacidad en pacientes con dolor lumbar crónico inespecífico y factores asociados, incluidos los impactos del dolor lumbar y factores psicosociales relacionados con la kinesiofobia, el catastrofismo, la ansiedad y la depresión. Pacientes: Se realizó un estudio transversal con 108 individuos adultos que presentaban lumbalgia crónica inespecífica. Los pacientes respondieron cuestionarios previamente validados, a saber, el Inventario Breve de Dolor, el Cuestionario de Discapacidad de Roland-Morris, la Escala de Catastrofización del Dolor, la Escala de Kinesiofobia de Tampa y la Escala de Ansiedad y Depresión Hospitalaria. Resultados: La prevalencia de discapacidad observada fue del 65,7%, siendo la puntuación media de discapacidad de 15,7±5,3 puntos en el Cuestionario de discapacidad de Roland-Morris. Aunque la intensidad del dolor y otros dominios del Inventario Breve de Dolor, como la ansiedad, la depresión y la kinesiofobia grave, fueron significativos en los análisis bivariados, no se asociaron con la discapacidad en el análisis multivariado. Sólo los pensamientos catastróficos (razón de prevalencia [PR]=1,19; intervalo de confianza [IC] del 95%: 1,07-1,32) y el dominio “caminar” (RP=1,08; IC del 95%: 1,03-1,14) permanecieron estadísticamente asociados con la discapacidad. Conclusión: La catastrofización del dolor y el impacto en la marcha se asociaron con discapacidad en personas con dolor lumbar crónico inespecífico. Los pensamientos y conductas de control motor durante las actividades funcionales se consideraron aspectos relevantes para una mejor valoración y tratamiento de estos pacientes.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Catastrofización , Dolor de la Región Lumbar , Impacto Psicosocial , Prevalencia , Ansiedad , Depresión , Miedo , Movimiento , Estudios Transversales , Encuestas y Cuestionarios
4.
Rehabilitacion (Madr) ; 57(2): 100750, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35868884

RESUMEN

INTRODUCTION AND OBJECTIVES: Chronic low back pain is the main cause of disability worldwide, generating high costs for society. To evaluate the prevalence of disability in patients with non-specific chronic low back pain and associated factors, including the impacts of low back pain and psychosocial factors linked to kinesiophobia, catastrophism, anxiety, and depression. PATIENTS: A cross-sectional study was carried out with 108 adult individuals who had non-specific chronic low back pain. The patients answered previously validated questionnaires, namely the Brief Pain Inventory, the Roland-Morris Disability Questionnaire, the Pain Catastrophizing Scale, the Tampa Kinesiophobia Scale, and the Hospital Anxiety and Depression Scale. RESULTS: The prevalence of disability observed was 65.7%, with the mean disability score being 15.7±5.3 points in the Roland-Morris Disability Questionnaire. Although pain intensity and other domains of the Brief Pain Inventory, like anxiety, depression, and severe kinesiophobia were significant in the bivariate analyses, they were not associated with disability in the multivariate analysis. Only catastrophic thoughts (prevalence ratio [PR]=1.19; 95% confidence interval [CI]: 1.07-1.32), and the 'walking' domain (PR=1.08; 95% CI: 1.03-1.14) remained statistically associated with disability. CONCLUSION: Pain catastrophization and impact on gait were associated with disability in individuals with non-specific chronic low back pain. Motor control thoughts and behaviors during functional activities were considered to be relevant aspects for the better assessment and treatment of these patients.


Asunto(s)
Dolor de la Región Lumbar , Adulto , Humanos , Estudios Transversales , Encuestas y Cuestionarios , Catastrofización/psicología , Ansiedad/etiología
5.
Braz. j. med. biol. res ; 56: e12682, 2023. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1447681

RESUMEN

Preventing the replication of adenovirus could have practical uses, such as controlling infection with wild-type virus or in applications involving recombinant vectors. Mainly transient methods have been used to inhibit adenovirus replication, including siRNA or drugs. Here, we tested whether stable expression of shRNA designed to target hexon, Iva2, or pol can inhibit the replication of a recombinant adenoviral vector, Ad-LacZ (serotype 5, E1/E3 deleted), in 293T cells. Significant knockdown correlating with reduced Ad-LacZ replication was achieved only when hexon was targeted. Cell sorting and isolation of cellular clones further accentuated knockdown of the hexon transcript, reduced protein levels by more than 90%, and diminished adenovirus production. As visualized by transmission electron microscopy, the cellular clone expressing the hexon-specific shRNA yielded 89.2% fewer particles compared to the parental 293T cells. Full scale production followed by purification revealed a 90.2% reduction in Ad-LacZ biological titer. These results support the notion that stable expression of shRNA can be used as a means to control adenovirus replication.

6.
Bioresour Technol ; 345: 126458, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34863850

RESUMEN

Environmental problems due to utilization of fossil-derived materials for energy and chemical generation has prompted the use of renewable alternative sources, such as lignocellulose biomass (LB). Indeed, the production of biomolecules and biofuels from LB is among the most important current research topics aiming to development a sustainable bioeconomy. Yet, the industrial use of LB is limited by the recalcitrance of biomass, which impairs the hydrolysis of the carbohydrate fractions. Hydrodynamic cavitation (HC) and Advanced Oxidative Processes (AOPs) has been proposed as innovative pretreatment strategies aiming to reduce process time and chemical inputs. Therefore, the underlying mechanisms, procedural strategies, influence on biomass structure, and research gaps were critically discussed in this review. The performed discussion can contribute to future developments, giving a wide overview of the main involved aspects.


Asunto(s)
Hidrodinámica , Lignina , Biocombustibles , Biomasa , Lignina/metabolismo , Estrés Oxidativo
7.
J Hazard Mater ; 394: 122522, 2020 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-32200241

RESUMEN

Mixed micelles of linear alkylbenzene sulfonic acid (LAS) and ether sulfate-based surfactants (SLEnS) can be added in household products and cleaning agents. SLEnS with higher ethylene oxide (EO) units in the head groups have economic and environmental advantages. This work aims to assess the influence of the number of EO units in the ecotoxicity of seven variants of SLEnS-LAS micelles (0-50 EO units) in soils. Ecotoxicological tests were carried out to assess emergence and growth of four plants species and reproduction of collembolans. Most of the variants inhibited plants growth at the highest concentrations (1237.5 µg SLEnS kg-1 of soildw). For reproduction, lower number of EO units resulted in EC50 from 924.2 (95 % CL: 760.7-1063.4) to 963.2 (95 % CL: 676.9-1249.6) µg SLEnS kg-1 of soildw, whereas for higher number of EO units (50 and 30) no inhibition was reported. Based on these results, we suggest that a higher number of EO units contribute to less hazardous formulations, confirming that different designs of surfactants may contribute to changes in the responses of terrestrial organisms. Therefore, we demonstrate that standardized ecotoxicological assays may contribute to more sustainable and effective formulations, when used upstream, prior to manufacture and marketing.


Asunto(s)
Artrópodos/efectos de los fármacos , Micelas , Plantas/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Tensoactivos/toxicidad , Animales , Bencenosulfonatos/química , Bencenosulfonatos/toxicidad , Éteres de Etila/química , Éteres de Etila/toxicidad , Estructura Molecular , Reproducción/efectos de los fármacos , Contaminantes del Suelo/química , Ésteres del Ácido Sulfúrico/química , Ésteres del Ácido Sulfúrico/toxicidad , Tensoactivos/química
8.
Prep Biochem Biotechnol ; 49(4): 328-333, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30712449

RESUMEN

L-asparaginase is an important enzyme used in the pharmaceutical and food industry, which can be produced by different microorganisms using low cost feedstocks. In this work, sugarcane bagasse (SCB) was used as support for enzyme production in solid-state fermentation (SSF) by A. terreus. Initially, the influence of the variables carbon and nitrogen sources on the enzyme production was studied following an experimental design carried out in Erlenmeyer flasks. Statistical analysis indicated the use of 0.54% of starch, 0% of maltose, 0.44% of asparagine, and 1.14% of glutamine in the medium, resulting in enzyme activity per volume of produced extract of 120.723 U/L. Then, these conditions were applied in a horizontal column reactor filled with SCB, producing 105.3 U/L of enzyme activity. Therefore, the potential of extracellular L-asparaginase enzyme production in the column reactor using sugarcane bagasse as support was demonstrated and it represents a system that can favor large scale production.


Asunto(s)
Asparaginasa/biosíntesis , Aspergillus/enzimología , Reactores Biológicos , Celulosa/química , Fermentación , Saccharum/química , Asparaginasa/aislamiento & purificación
9.
Chem Biol Interact ; 281: 89-97, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29273566

RESUMEN

Melanoma incidence increases every year worldwide and is responsible for 80% of skin cancer deaths. Due to its metastatic potential and resistance to almost any treatments such as chemo, radio, immune and targeted-therapy, the patients still have a poor prognosis, especially at metastatic stage. Considering that, it is crucial to find new therapeutic approaches to overcome melanoma resistance. Here we investigated the effect of cisplatin (CDDP), one of the chemotherapeutic agents used for melanoma treatment, in association with nutritional deprivation in murine melanoma cell lines. Cell death and autophagy were evaluated after the treatment with cisplatin, nutritional deprivation and its association using an in vitro model of murine melanocytes malignant transformation to metastatic melanoma. Our results showed that nutritional deprivation augmented cell death induced by cisplatin in melanoma cells, especially at the metastatic subtype, with slight effects on melanocytes. Mechanistic studies revealed that although autophagy was present at high levels in basal conditions in melanoma cells, was not essential for cell death process that involved mitochondrial damage, reactive oxygen species production and possible glycolysis inhibition. In conclusion, nutritional shortage in combination with chemotherapeutic drugs as cisplatin can be a valuable new therapeutic strategy to overcome melanoma resistance.


Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Cisplatino/farmacología , Animales , Proteína 7 Relacionada con la Autofagia/antagonistas & inhibidores , Proteína 7 Relacionada con la Autofagia/genética , Proteína 7 Relacionada con la Autofagia/metabolismo , Línea Celular , Glucosa/metabolismo , Macrólidos/farmacología , Melanocitos/citología , Melanocitos/efectos de los fármacos , Melanocitos/metabolismo , Melanoma/metabolismo , Melanoma/patología , Potenciales de la Membrana/efectos de los fármacos , Ratones , Microscopía Fluorescente , Proteínas Asociadas a Microtúbulos/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Especies Reactivas de Oxígeno/metabolismo
11.
Skin Res Technol ; 23(3): 429-436, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27882608

RESUMEN

BACKGROUND/PURPOSE: Human skin anisotropy is difficult to quantify. The Cutiscan® , is allegedly, the first biometrical system to provide information on the elastic and viscoelastic properties, as well as on anisotropy and directionality of the human skin in vivo. Thus, this study aims to contribute to characterize this new device and its applicability, and to compare its behavior with two other well-known devices-the Cutometer® and the Reviscometer® . METHODS: Measurements were conducted with each device in three different anatomical sites (forehead, forearm and leg) of 20 female volunteers engaged after informed consent. The participants in the study were aged 19-73 years (mean age 37 ± 18.7 years old), and were divided in two groups (n = 10), based on their age - Group I, mean age 22 ± 1.3 years; Group II, mean age 52 ± 13.7 years. RESULTS: All devices were useful tools to explore the anatomical and the age dependant changes in biomechanical terms, showing different discriminative capacities. Interesting correlations were established between the variables provided by the equipment. CONCLUSION: The Cutiscan® descriptors delivered excellent relationships with those from Cutometer® and Reviscometer® , while providing more detailed information about skin anisotropy through a full 360° analysis.


Asunto(s)
Anisotropía , Dermatología/instrumentación , Elasticidad/fisiología , Piel/anatomía & histología , Adulto , Anciano , Fenómenos Biomecánicos/fisiología , Biometría/instrumentación , Diseño de Equipo/estadística & datos numéricos , Femenino , Antebrazo/anatomía & histología , Antebrazo/patología , Frente/anatomía & histología , Frente/patología , Humanos , Persona de Mediana Edad , Piel/patología , Envejecimiento de la Piel/fisiología , Fenómenos Fisiológicos de la Piel
12.
Clin Microbiol Infect ; 22(6): 566.e9-566.e19, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27021425

RESUMEN

Pneumocystis jirovecii causes severe interstitial pneumonia (PcP) in immunosuppressed patients. This multicentre study assessed the distribution frequencies of epidemiologically relevant genetic markers of P. jirovecii in different geographic populations from Portugal, the USA, Spain, Cuba and Mozambique, and the relationship between the molecular data and the geographical and clinical information, based on a multifactorial approach. The high-throughput typing strategy for P. jirovecii characterization consisted of DNA pooling using quantitative real-time PCR followed by multiplex-PCR/single base extension. The frequencies of relevant P. jirovecii single nucleotide polymorphisms (mt85, SOD110, SOD215, DHFR312, DHPS165 and DHPS171) encoded at four loci were estimated in ten DNA pooled samples representing a total of 182 individual samples. Putative multilocus genotypes of P. jirovecii were shown to be clustered due to geographic differences but were also dependent on clinical characteristics of the populations studied. The haplotype DHFR312T/SOD110C/SOD215T was associated with severe AIDS-related PcP and high P. jirovecii burdens. The frequencies of this genetic variant of P. jirovecii were significantly higher in patients with AIDS-related PcP from Portugal and the USA than in the colonized patients from Portugal, and Spain, and children infected with P. jirovecii from Cuba or Mozambique, highlighting the importance of this haplotype, apparently associated with the severity of the disease and specific clinical groups. Patients from the USA and Mozambique showed higher rates of DHPS mutants, which may suggest the circulation of P. jirovecii organisms potentially related with trimethoprim-sulfamethoxazole resistance in those geographical regions. This report assessed the worldwide distribution of P. jirovecii haplotypes and their epidemiological impact in distinct geographic and clinical populations.


Asunto(s)
Ensayos Analíticos de Alto Rendimiento , Tipificación Molecular/métodos , Técnicas de Tipificación Micológica/métodos , Pneumocystis carinii/clasificación , Pneumocystis carinii/genética , Neumonía por Pneumocystis/epidemiología , Neumonía por Pneumocystis/microbiología , Adolescente , Adulto , Anciano , Análisis por Conglomerados , Femenino , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular/métodos , Reacción en Cadena de la Polimerasa Multiplex/métodos , Pneumocystis carinii/aislamiento & purificación , Polimorfismo de Nucleótido Simple , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Adulto Joven
13.
Sci Total Environ ; 547: 413-421, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26795542

RESUMEN

Aiming at contributing new insights into the effects of nanomaterials (NMs) in the terrestrial ecosystem, this study evaluated the impacts of organic nano-vesicles of sodium dodecyl sulphate/didodecyl dimethylammonium bromide (SDS/DDAB) on the emergence and growth of plant seeds, and on the avoidance and reproduction of soil invertebrates. For this purpose several ecotoxicological assays were performed with different test species (terrestrial plants: Zea mays, Avena sativa, Brassica oleracea and Lycopersicon esculentum; soil invertebrates: Eisenia andrei and Folsomia candida). A wide range of SDS/DDAB concentrations were tested, following standard protocols, and using the standard OECD soil as a test substrate (5% of organic matter). The aqueous suspensions of SDS/DDAB, used to spike the soils, were characterised by light scattering techniques for hydrodynamic size of the vesicles, aggregation index, polydispersity index, zeta potential and surface charge. The SDS/DDAB concentrations in the test soil were analysed by HPLC-UV at the end of the assays. Invertebrate species were revealed to be sensitive to nano-SDS/DDAB upon immediate exposure to freshly spiked soils. However, the degradation of SDS/DDAB nano-vesicles in the soil with time prevented the occurrence of significant reproduction effects on soil invertebrates. Plants were not particularly sensitive to SDS/DDAB, except B. oleracea (at concentrations above 375 mg kg(-1)dw). The results gathered in this study allowed a preliminary determination of a risk limit to nano-SDS/DDAB. The low toxicity of SDS/DDAB nano-vesicles could be explained by its high and fast degradation in the soil. The soil microbial community could have an important role in the fate of this NM, thus it is of remarkable importance to improve this risk limit by taking into account specific data addressing this community.


Asunto(s)
Nanoestructuras/toxicidad , Compuestos de Amonio Cuaternario/toxicidad , Dodecil Sulfato de Sodio/toxicidad , Contaminantes del Suelo/toxicidad , Animales , Bioensayo , Ecotoxicología , Oligoquetos , Plantas , Suelo
14.
Curr Microbiol ; 72(2): 133-138, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26507335

RESUMEN

The use of sugarcane bagasse hemicellulosic hydrolysates presents an interesting alternative to second generation (2G) ethanol production. Techniques to enhance the fermentation process, e.g., the use of immobilized cells, is one of the key factors for efficient production. Here, the effect of two important parameters (cell concentration in immobilized system and stirring rate) on the 2G ethanol production using the wild Brazilian yeast S. shehatae UFMG-HM 52.2 immobilized in calcium alginate matrix are presented. A 2(2) full factorial design of experiments was carried out to evaluate the effect of cell concentrations in sodium alginate solution for immobilized bead production (3.0, 6.0, and 9.0 g/L) and stirring rate (150, 200, and 250 rpm) for 2G ethanol production. Statistical analysis showed that the use of both variables at low levels enhanced ethanol yield (YP/S). Under these process conditions, YP/S of 0.31 g/g and ethanol productivity (Qp) of 0.12 g/L h were achieved. Results showed the potential of this immobilized yeast in 2G ethanol production from C5 sugars and demonstrate the importance of adequate cell concentration in immobilized systems, a finding that stands to increase bioprocesses yields and productivity.


Asunto(s)
Reactores Biológicos/microbiología , Células Inmovilizadas/metabolismo , Etanol/metabolismo , Glicósido Hidrolasas/metabolismo , Saccharomycetales/metabolismo , Biotecnología/métodos , Brasil
15.
Colloids Surf B Biointerfaces ; 135: 183-192, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26263210

RESUMEN

Pickering emulsions are stabilized by solid particles instead of surfactants and have been widely investigated in pharmaceutical and cosmetic fields since they present less adverse effects than the classical emulsions. A quality by design (QbD) approach was applied to the production of w/o emulsions stabilized by starch. A screening design was conducted to identify the critical variables of the formula and the process affecting the critical quality properties of the emulsion (droplet size distribution). The optimization was made by establishing the Design Space, adjusting the concentration of starch and the quantity of the internal aqueous phase. The emulsion production process was, in turn, adjusted by varying the time and speed of stirring, to ensure quality and minimum variability. The stability was also investigated, demonstrating that an increase in starch concentration improves the stability of the emulsion. Rheological and mechanical studies indicated that the viscosity of the emulsions was enhanced by the addition of starch and, to a higher extent, by the presence of different lipids. The developed formulations was considered non-irritant, by an in vitro assay using human cells from skin (Df and HaCat) with the cell viability higher than 90% and, with self-preserving properties. Finally, the QbD approach successfully built quality in Pickering emulsions, allowing the development of hydrophilic drug-loaded emulsions stabilized by starch with desired organoleptic and structural characteristics. The results obtained suggest that these systems are a promising vehicle to be used in products for topical administration.


Asunto(s)
Sistemas de Liberación de Medicamentos , Excipientes/química , Almidón/química , Administración Tópica , Supervivencia Celular , Diseño de Fármacos , Emulsiones , Humanos , Lípidos , Tamaño de la Partícula , Polvos , Reología , Piel/citología , Piel/metabolismo , Viscosidad
16.
Clin Microbiol Infect ; 21(4): 379.e1-10, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25630458

RESUMEN

The diagnosis of Pneumocystis pneumonia (PCP) relies on microscopic visualization of Pneumocystis jirovecii organisms or DNA detection in pulmonary specimens. This study aimed to assess the usefulness of (1-3)-ß-d-glucan (BG), Krebs von den Lungen-6 antigen (KL-6), lactate dehydrogenase (LDH) and S-adenosyl methionine (SAM) as serologic biomarkers in the diagnosis of PCP. Serum levels of BG, KL-6, LDH and SAM were investigated in 145 Portuguese patients, 50 patients from the Netherlands, 25 Spanish patients and 40 Portuguese blood donors. Data on clinical presentation, chest imaging and gasometry tests were available. PCP cases were confirmed by microscopy and PCR techniques. A cost-effectiveness analysis was performed. BG was found to be the most reliable serologic biomarker for PCP diagnosis, followed by KL-6, LDH and SAM. The BG/KL-6 combination test was the most accurate serologic approach for PCP diagnosis, with 94.3% sensitivity and 89.6% specificity. Although less sensitive/specific than the reference standard classic methods based on bronchoalveolar lavage followed by microscopic or molecular detection of P. jirovecii organisms, the BG/KL-6 test may provide a less onerous procedure for PCP diagnosis, as it uses a minimally invasive and inexpensive specimen (blood), which may be also a major benefit for the patient's care. The BG/KL-6 combination test should be interpreted within the clinical context, and it may be used as a preliminary screening test in patients with primary suspicion of PCP, or as an alternative diagnostic procedure in patients with respiratory failure or in children, avoiding the associated risk of complications by the use of bronchoscopy.


Asunto(s)
Biomarcadores/sangre , Neumonía por Pneumocystis/diagnóstico , Pruebas Serológicas/métodos , Adolescente , Adulto , Anciano , Niño , Preescolar , Análisis Costo-Beneficio , Femenino , Humanos , L-Lactato Deshidrogenasa/sangre , Masculino , Microscopía , Persona de Mediana Edad , Mucina-1/sangre , Países Bajos , Pneumocystis carinii , Reacción en Cadena de la Polimerasa , Portugal , Proteoglicanos , Radiografía Torácica , S-Adenosilmetionina/sangre , Sensibilidad y Especificidad , España , Adulto Joven , beta-Glucanos/sangre
17.
Eur J Clin Microbiol Infect Dis ; 33(7): 1173-80, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24487911

RESUMEN

Pneumocystis pneumonia (PcP) is a major HIV-related illness caused by Pneumocystis jirovecii. Definitive diagnosis of PcP requires microscopic detection of P. jirovecii in pulmonary specimens. The objective of this study was to evaluate the usefulness of two serum markers in the diagnosis of PcP. Serum levels of (1-3)-beta-d-glucan (BG) and lactate dehydrogenase (LDH) were investigated in 100 HIV-positive adult patients and 50 healthy blood donors. PcP cases were confirmed using indirect immunofluorescence with monoclonal anti-Pneumocystis antibodies and nested-PCR to amplify the large subunit mitochondrial rRNA gene of P. jirovecii in pulmonary specimens. BG and LDH levels in serum were measured using quantitative microplate-based assays. BG and LDH positive sera were statistically associated with PcP cases (P ≤ 0.001). Sensitivity, specificity, positive/negative predictive values (PPV/NPV), and positive/negative likelihood ratios (PLR/NLR) were 91.3 %, 61.3 %, 85.1 %, 79.2 %, 2.359, and 0.142, respectively, for the BG kit assay, and 91.3 %, 35.5 %, 75.9 %, 64.7 %, 1.415 and 0.245, respectively, for the LDH test. Serologic markers levels combined with the clinical diagnostic criteria for PcP were evaluated for their usefulness in diagnosis of PcP. The most promising cutoff levels for diagnosis of PcP were determined to be 400 pg/ml of BG and 350 U/l of LDH, which combined with clinical data presented 92.8 % sensitivity, 83.9 % specificity, 92.8 % PPV, 83.9 % NPV, 5.764 PLR and 0.086 NLR (P < 0.001). This study confirmed that BG is a reliable indicator for detecting P. jirovecii infection. The combination between BG/LDH levels and clinical data is a promising alternative approach for PcP diagnosis.


Asunto(s)
Biomarcadores/sangre , L-Lactato Deshidrogenasa/sangre , Neumonía por Pneumocystis/diagnóstico , beta-Glucanos/sangre , Adulto , Anciano , Femenino , Infecciones por VIH/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Proteoglicanos , Sensibilidad y Especificidad , Suero/química , Adulto Joven
18.
Chem Biol Interact ; 206(2): 279-88, 2013 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-24121004

RESUMEN

Autophagy is a mechanism of protection against various forms of human diseases, such as cancer, in which autophagy seems to have an extremely complex role. In cancer, there is evidence that autophagy may be oncogenic in some contexts, whereas in others it clearly contributes to tumor suppression. In addition, studies have demonstrated the existence of a complex relationship between autophagy and cell death, determining whether a cell will live or die in response to anticancer therapies. Nevertheless, we still need to complete the autophagy-apoptosis puzzle in the tumor context to better address appropriate chemotherapy protocols with autophagy modulators. Generally, tumor cell resistance to anticancer induced-apoptosis can be overcome by autophagy inhibition. However, when an extensive autophagic stimulus is activated, autophagic cell death is observed. In this review, we discuss some details of autophagy and its relationship with tumor progression or suppression, as well as role of autophagy-apoptosis in cancer treatments.


Asunto(s)
Apoptosis , Autofagia , Neoplasias/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Comunicación Celular , Resistencia a Antineoplásicos , Humanos , Chaperonas Moleculares/metabolismo , Metástasis de la Neoplasia , Neoplasias/metabolismo , Neoplasias/patología
19.
Arq. bras. med. vet. zootec ; 65(3): 669-674, June 2013. ilus, graf
Artículo en Portugués | LILACS | ID: lil-679096

RESUMEN

Avaliou-se a eficiência do cateterismo posterior do plexo braquial em cães para promover bloqueio motor e sensitivo, por meio de três protocolos anestésicos. Foram utilizados nove cães, machos e fêmeas, sem distinção de raça e idade, com peso variando de 6 a 15kg, distribuídos em três grupos de três animais por grupo. Após a confirmação do correto posicionamento do cateter pela via posterior do plexo braquial por meio do exame radiográfico, foram aplicadas as medicações de acordo com os grupos. No grupo 1, a solução anestésica de bupivacaína 0,5% sem vasoconstrictor, na dose de 2mg.kg-1, foi usada isoladamente. No grupo 2, a solução anestésica de bupivacaína foi associada ao butorfanol na dose de 0,25mg.kg-1 . No grupo 3, o fentanil, na dose de 0,005mg.kg¹, foi associado à solução anestésica de bupivacaína. Não houve diferença estatística significante entre os grupos. Observou-se que a duração dos bloqueios motor e sensitivo foi clinicamente maior no grupo 2. O cateterismo posterior do plexo braquial permite a aplicação de fármacos mais próximos do plexo nervoso, promovendo analgesia complementar nos membros anteriores.


We evaluated the efficiency of the posterior brachial plexus catheterization in dogs to promote motor and sensory block using three anesthetic protocols. We used nine dogs, males and females, without distinction of race and age, weighing 6 to 15kg which were divided into three groups of three animals per group. After confirming the correct positioning of the catheter through the posterior brachial plexus through radiographic examination, the medications were administered according to the groups. In group 1 the anesthetic bupivacaine 0.5% without a vasoconstrictor dose of 2mg.kg-1 was used alone. In group 2 the anesthetic bupivacaine was associated with butorphanol at a dose of 0.25mg.kg-1. In group 3, the fentanyl dose was associated with 0.005mg.kg-1 anesthetic bupivacaine. There was no statistically significant difference between groups. It was observed that the duration of sensory and motor block was clinically higher in group 2. The posterior brachial plexus catheterization allows the application of drugs closer to the nerve plexus promoting additional analgesia in the forelimbs.


Asunto(s)
Animales , Perros , Anestesia , Butorfanol/farmacología , Fentanilo/farmacología , Radiología/métodos , Cateterismo , Perros
20.
Sci Total Environ ; 458-460: 290-7, 2013 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-23665417

RESUMEN

The rapid development of nanoparticles (NP) for industrial applications and large-volume manufacturing, with its subsequent release into the environment, raised the need to understand and characterize the potential effects of NP to biota. Accordingly, this work aimed to assess sublethal effects of five NP to the white-rot fungi species Trametes versicolor, Lentinus sajor caju, Pleurotus ostreatus, and Phanerochaete chrysosporium. Each species was exposed to serial dilutions of the following NP: organic-vesicles of SDS/DDAB and of Mo/NaO; gold-NP, quantum dot CdSe/ZnS, and Fe/Co. Fungi growth rate was monitored every day, and at the end of assay the mycelium from each replicate was collected to evaluate possible changes in its chemical composition. For all NP-suspensions the following parameters were characterized: hydrodynamic diameter, surface charge, aggregation index, zeta potential, and conductivity. All tested NP tended to aggregate when suspended in aqueous media. The obtained results showed that gold-NP, CdSe/ZnS, Mo/NaO, and SDS/DDAB significantly inhibited the growth of fungi with effects on the mycelium chemical composition. Among the tested NP, gold-NP and CdSe/ZnS were the ones exerting a higher effect on the four fungi. Finally to our knowledge, this is the first study reporting that different types of NP induce changes in the chemical composition of fungi mycelium.


Asunto(s)
Basidiomycota/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Micelio/efectos de los fármacos , Análisis de Varianza , Basidiomycota/química , Basidiomycota/crecimiento & desarrollo , Micelio/química , Especificidad de la Especie , Espectroscopía Infrarroja por Transformada de Fourier
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