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1.
Lett Appl Microbiol ; 72(4): 445-457, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33278831

RESUMEN

Textile effluent is generally complicated to manage because of its extremely noxious and recalcitrant coloured compositions. Mycoremediation is an extensively used strategy for the competent degradation of hazardous pollutants present in textile effluent. Fungus could be immobilized in synthetic or natural matrices. The current study shows the decolourization of the textile effluent by 85·5 and 98·5% within 6 h using suspended and immobilized fungus, Geotrichum candidum with optimized parameters like inoculum size (5%), pH (4·5), and temperature (30°C). To maintain a high biomass of fungal population and enhance the retention of fungal strain in the contaminated sites, the fungi need to be immobilized. Hence, the fungus was immobilized naturally onto the selected inert support that is, coconut fibres by the means of adsorption, where they grew as active films on the fibres after being grown in the culture broth. The optimized process parameters of inoculum size, fibre quantity and agitation speed for immobilized G. candidum were 5%, 2·2 g l-1 of effluent and 100 rev min-1 respectively. High level of laccase (22 and 25 U l-1 in suspended and immobilized fungal cells treatment respectively) was observed during the process of decolourization and it was found that decolourization was directly proportional to the laccase activity. The UV-vis, FTIR, 1 H NMR and GC-MS analyses of treated textile industrial wastewater revealed the degradation of toxic pollutants in the textile effluent and formation of lower molecular weight intermediates. The study revealed a higher efficacy of immobilized G. candidum in comparison to suspended fungal culture, employing ligninolytic enzyme laccase, which catalyzes the degradation/transformation of aromatic dyes in the textile effluent thus decolourizing it.


Asunto(s)
Biodegradación Ambiental , Colorantes/metabolismo , Geotrichum/metabolismo , Aguas Residuales/química , Purificación del Agua/métodos , Residuos Industriales/análisis , Lacasa/metabolismo , Textiles
2.
J Appl Microbiol ; 129(6): 1633-1643, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32491245

RESUMEN

AIM: The aim of the study is to investigate the efficiency of Geotrichum candidum in the decolourization and mineralization of synthetic azo dyes. METHODS AND RESULTS: It includes screening of enzymes from G. candidum and its optimization, followed by decolourization and mineralization studies. Decolourization was observed to be maximum in methyl orange (94·6%) followed by Congo red (85%), trypan blue (70·4%) and Eriochrome Black T (55·6%) in 48 h, suggesting the plausible degradation of the azo dyes by G. candidum. The enzyme activity study showed that DyP-type peroxidase has highest activity of 900 mU ml-1 compared to that of laccase (405 mU ml-1 ) and lignin peroxidase (LiP) (324 mU ml-1 ) at optimized pH (6) and temperature (35°C). Moreover, the rate of decolourization was found to be directly proportional to the production of laccase and LiP, unlike DyP-type peroxidase. Furthermore, mineralization study demonstrated reduction in aromatic amines, showing 20% mineralization of methyl orange. CONCLUSION: Geotrichum candidum with its enzyme system is able to efficiently decolourize and mineralize the experimental azo dyes. SIGNIFICANCE AND IMPACT OF THE STUDY: The efficient decolourization and mineralization of azo dyes makes G. candidum a promising alternative in the treatment of textile effluent contaminated with azo dyes.


Asunto(s)
Compuestos Azo/metabolismo , Colorantes/metabolismo , Proteínas Fúngicas/metabolismo , Geotrichum/enzimología , Descoloración del Agua/métodos , Biodegradación Ambiental , Geotrichum/metabolismo , Lacasa/metabolismo , Peroxidasa/metabolismo , Peroxidasas/metabolismo , Textiles
3.
J Postgrad Med ; 66(1): 28-34, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31898596

RESUMEN

Patients often approach a pharmacist instead of visiting a doctor for minor ailments such as cough, cold, allergies, pain, fever, acidity, diarrhea, and skin-related conditions. Purchase of specific medicines over the counter is legally recognized in most countries. 'Over-the-Counter (OTC) Medicines' means drugs which are legally allowed to be sold by pharmacists without need for a prescription. The term does not have a legal definition in India. Technically, drugs are OTC unless they are specifically stated as prescription only drugs. OTC drugs allow faster and cheaper access to healthcare; however, their misuse and adverse health effects cause concerns. This article describes concept of OTC medicines and practices in India against the background of globally prevalent regulations and practices. A recognized category of OTC medicines by law, patient awareness programs, and support of pharmacists and pharmaceutical companies are required to optimize the use of OTC medicines in India.


Asunto(s)
Medicamentos sin Prescripción , Farmacéuticos , Automedicación , Conocimientos, Actitudes y Práctica en Salud , Humanos , India , Rol Profesional , Salud Pública , Automedicación/efectos adversos
4.
Curr Genet ; 65(2): 561-573, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30467716

RESUMEN

Spliceosome disassembly is catalyzed by the NineTeen-related (NTR) complex, which is constituted by several proteins, including Cwc23, Ntr1, and Ppr43. Cwc23 is an essential J-protein in Saccharomyces cerevisiae that recruits Ntr1, an NTC-related G-patch protein, to the spliceosome. Ntr1 interacts with Prp43, a DExD/H box RNA helicase protein, which facilitates the disassembly of spliceosomal intermediates. The interaction between Ntr1 and Prp43 is conserved and crucial for the disassembly process. However, the J-protein component of this complex is not studied in other eukaryotes. In silico analysis supported by results of yeast complementation and two-hybrid studies suggests that while Prp43 is highly conserved, both Ntr1 and Cwc23 are co-evolving components of the disassembly triad. The J-domain of Cwc23, which is otherwise dispensable for its function, is highly conserved, whereas the functionally critical C-terminus has significantly diverged in Cwc23 orthologs. Some eukaryotic orthologs of Cwc23 contain a distinct RNA recognition motif at their C-terminus and are able to bind RNA in vitro. Based on the results presented in this study, we propose that RNA-binding activity in some eukaryotic orthologs of Cwc23 might provide additional functional diversity or robustness to the J-protein/Hsp70 machine in spliceosomal remodelling processes.


Asunto(s)
Evolución Biológica , ARN/genética , ARN/metabolismo , Empalmosomas/metabolismo , Biología Computacional/métodos , Bases de Datos Genéticas , Modelos Moleculares , Complejos Multiproteicos/metabolismo , Unión Proteica , Conformación Proteica , ARN/química , Empalme del ARN , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Relación Estructura-Actividad
5.
Reprod Fertil Dev ; 30(12): 1595-1603, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29860969

RESUMEN

Spermiation (sperm release) is the culmination of a spermatid's journey in the seminiferous epithelium. After a long association with the Sertoli cell, spermatids have to finally 'let go' of the support from Sertoli cells in order to be transported to the epididymis. Spermiation is a multistep process characterised by removal of excess spermatid cytoplasm, recycling of junctional adhesion molecules by endocytosis, extensive cytoskeletal remodelling and final spermatid disengagement. Successful execution of all these events requires coordinated regulation by endocrine and paracrine factors. This review focuses on the endocrine regulation of spermiation. With the aim of delineating how hormones control the various aspects of spermiation, this review provides an analysis of recent advances in research on the hormonal control of molecules associated with the spermiation machinery. Because spermiation is one of the most sensitive phases of spermatogenesis to variations in hormone levels, understanding their molecular control is imperative to advance our knowledge of the nuances of spermatogenesis and male fertility.


Asunto(s)
Andrógenos/metabolismo , Movimiento Celular/fisiología , Estrógenos/metabolismo , Oxitocina/metabolismo , Espermatogénesis/fisiología , Espermatozoides/citología , Animales , Humanos , Masculino , Epitelio Seminífero/citología , Epitelio Seminífero/metabolismo , Espermátides/citología , Espermátides/metabolismo , Espermatozoides/metabolismo , Testículo/citología , Testículo/metabolismo
6.
Nanotechnology ; 27(32): 325704, 2016 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-27348419

RESUMEN

We present optical studies of two different size distributions of silver triangular nanoprisms, one with a dipole resonance at 520 nm and the other with a dipole resonance at 650 nm, placed in different media. Significant wavelength-dependent depolarization of scattered light from the silver nanoprisms suspended in water indicates strong interference of multiple surface plasmon resonant modes in the same particle. We use this depolarization as a probe of light scattering by the nanoprisms in a lipid solution due to the rejection of a polarized background scattering. Also, the silver nanoprisms were embedded in a polyvinyl alcohol polymer matrix and oriented by stretching the polymer/nanoprism nanocomposite films. We observe significantly increased linear dichroism in the region associated with the plasmonic in-plane dipole mode upon stretching. Additionally, there is a weaker linear dichroism in the region associated with out-of-plane modes, which vanish in the extinction spectrum of the stretched nanocomposite film.

7.
Biochemistry ; 53(48): 7641-9, 2014 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-25488019

RESUMEN

The contraction of the right ventricle (RV) expels blood into the pulmonary circulation, and the contraction of the left ventricle (LV) pumps blood into the systemic circulation through the aorta. The respective afterloads imposed on the LV and RV by aortic and pulmonary artery pressures create very different mechanical requirements for the two ventricles. Indeed, differences have been observed in the contractile performance between left and right ventricular myocytes in dilated cardiomyopathy, in congestive heart failure, and in energy usage and speed of contraction at light loads in healthy hearts. In spite of these functional differences, it is commonly believed that the right and left ventricular muscles are identical because there were no differences in stress development, twitch duration, work performance, or power among the RV and LV in dogs. This report shows that on a mesoscopic scale [when only a few molecules are studied (here three to six molecules of actin) in ex vivo ventricular myofibrils], the two ventricles in rigor differ in the degree of orientational disorder of actin within in filaments and during contraction in the kinetics of the cross-bridge cycle.


Asunto(s)
Actinas/química , Actinas/metabolismo , Ventrículos Cardíacos/metabolismo , Miosinas/química , Miosinas/metabolismo , Animales , Perros , Femenino , Cinética , Ratones , Ratones Endogámicos C57BL , Modelos Cardiovasculares , Modelos Moleculares , Proteínas Motoras Moleculares/química , Proteínas Motoras Moleculares/metabolismo , Contracción Miocárdica , Miofibrillas/química , Miofibrillas/metabolismo , Distribución Tisular , Función Ventricular
8.
Haemophilia ; 19(2): 304-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23174010

RESUMEN

Factor-Eight-Inhibitor-Bypassing-Activity (FEIBA) is a bypassing-agent used to control spontaneous bleeding or cover surgical interventions in Haemophiliacs who develop neutralizing antibodies against FVIII/FIX. The market lot-release of FEIBA is dependent on specific clot-based assays, carried out by both the manufacturer and regulatory authorities, relative to manufacturer's in-house standards, which are produced on a small-scale and are replaced frequently. We sought to standardize the FEIBA assay by developing a FEIBA primary standard which would be internationally available in sufficiently large quantities, with a predicted lifetime of many years. A collaborative study involving the manufacturer and three regulatory authorities, was carried out in which a candidate material, sample B (06/172), was calibrated by assays relative to the manufacturer's in-house FEIBA standards (C and D). All laboratories used their routine validated methods (16 APTT-assays, 8 ACTIN-FS-assays and 27 DAPTTIN-assays). Intra-laboratory geometric coefficients of variation (GCVs) for candidate B ranged from 3% to 29% (GCVs <9% from majority of labs). Assessment of inter-laboratory variability gave overall GCV values of 6.9% and 4.4% relative to standards C and D, respectively, for all methods. There was good agreement in potency estimation between laboratories using each of the three methods, with the overall potencies by the three methods differing by less than 10% of the overall mean, giving an overall combined potency of 28.0 units per ampoule. All participants agreed that candidate B (06/172) be established as the 1st NIBSC Working Standard for FEIBA with an assigned potency of 28.0 units per ampoule, based on combined results for both methods, relative to either standard C or D.


Asunto(s)
Factores de Coagulación Sanguínea/uso terapéutico , Coagulantes/uso terapéutico , Tiempo de Tromboplastina Parcial , Análisis de Varianza , Factores de Coagulación Sanguínea/análisis , Factores de Coagulación Sanguínea/normas , Calibración , Coagulantes/análisis , Coagulantes/normas , Estándares de Referencia , Procedimientos Quirúrgicos Operativos
9.
Luminescence ; 28(5): 755-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23055369

RESUMEN

Different metal complexes of Alq3 (K(+) , Sr(2+) , Ca(2+) and Mg(2+) ) were synthesized by the precipitation method. The characterization of photoluminescence showed that presence of Mg(2+) ion enhances photoluminescence of Alq3 phosphor. The emission spectra are observed at 560 nm when excited at a wavelength of 440 nm. The phosphor is excited at a longer wavelength in the blue region of small energy, so that it could be used as lamp phosphor. It is observed that the prepared phosphor AlMgq5 is more suitable than Alq3. The ionic radii of K(+) , Sr(2+) , Ca(2+) and Mg(2+) ions are in decreasing order. Therefore, the remarkable properties of AlMgq5 could be considered as promising materials as opto- or optoelectronic materials.


Asunto(s)
Compuestos Organometálicos/química , Luminiscencia , Modelos Moleculares , Compuestos Organometálicos/síntesis química , Procesos Fotoquímicos
10.
Pharmeur Bio Sci Notes ; 2023: 1-14, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37272308

RESUMEN

Chromogenic assay discrepancies were reported at General European Official Medicines Control Laboratories Network (GEON) meetings by laboratories testing FVIII-products. The objectives of the present investigation were to carry out a controlled collaborative study to examine these reports and to delineate the reasons for these discrepancies by assessing affected and unaffected FVIII products. The laboratories followed a strict study protocol, which included assessing their own individual observed factor X (FX) activation times, i.e. the time to reach 50% of maximal FX activation (T1/2), for each chromogenic kit. This measurement was used, in parallel with the kit manufacturers' prescribed FX activation times, to assess the performance of the chromogenic potency assays on FVIII test products. This study confirmed a significant discrepancy between Coatest® and Coamatic® kits and between Siemens and Coamatic® kits when the kit manufacturers' prescribed T1/2 incubation times were followed. Coamatic® kits tended to produce higher potencies than the Coatest® or Siemens kits. Furthermore, FX activation assays revealed marked differences between individual laboratories for all three chromogenic kits in the observed T1/2 incubation times, which also did not correspond to the prescribed T1/2 incubation times. The resulting differences in potency between kits, in some cases, were significantly reduced when using the actual observed T1/2 incubation times instead of the prescribed T1/2 incubation times. The study showed that FVIII potency discrepancies can occur between chromogenic kits. To compensate for this, laboratories should ideally perform FX activation curves for each new chromogenic kit in order to determine the correct observed T1/2 incubation times, which can then be used to determine FVIII potencies in therapeutic concentrates.


Asunto(s)
Factor VIII , Hemostáticos , Humanos , Factor VIII/uso terapéutico , Compuestos Cromogénicos , Pruebas de Coagulación Sanguínea/métodos , Laboratorios , Factor X
11.
Nanotechnology ; 23(25): 255102, 2012 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-22652439

RESUMEN

Magnetic nanoparticles (NP) were developed for the active brain targeting of water-soluble P-glycoprotein (P-gp) substrate rhodamine 123 (Rh123). The NP matrix of poly(lactide-co-glycolide) (PLGA) and methoxy poly(ethyleneglycol)-poly(lactic acid) (M-PEG-PLA) was prepared by single emulsion solvent evaporation of polymers with oleic acid-coated magnetic nanoparticles (OAMNP) and Rh123. All formulations were characterized in terms of morphology, particle size, magnetic content and Rh123 encapsulation efficiency. The maximum encapsulation efficiency of Rh123 was 45 ± 3% and of OAMNP was 42 ± 4%. The brain targeting and biodistribution study was performed on Sprague Dawley rats (3 groups, n = 6). Rh123 (0.4 mg kg(-1)) was administered in saline form, NP containing Rh123, and NP containing Rh123 in the presence of a magnetic field (0.8 T). The fluorimetric analysis of brain homogenates revealed a significant uptake (p < 0.05) of Rh123 in the magnetically targeted group relative to controls. These results were supported by fluorescence microscopy. This study reveals the ability of magnetically targeted nanoparticles to deliver substances to the brain, the permeation of which would otherwise be inhibited by the P-gp system.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Encéfalo/metabolismo , Portadores de Fármacos/farmacocinética , Colorantes Fluorescentes/farmacocinética , Nanopartículas de Magnetita/química , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/química , Animales , Química Encefálica , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Colorantes Fluorescentes/química , Histocitoquímica , Ácido Láctico/química , Masculino , Microscopía Fluorescente , Ácido Oléico/química , Polietilenglicoles/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas , Ratas Sprague-Dawley , Rodamina 123/química , Rodamina 123/farmacocinética , Distribución Tisular
12.
Nanotechnology ; 22(3): 035101, 2011 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-21149963

RESUMEN

This work reports the surface functionalization of polymeric PLGA nanoparticles by non-covalent insertion of a homo-bifunctional chemical crosslinker, bis(sulfosuccinimidyl) suberate (BS3) for targeted cancer therapy. We dissolved BS3 in aqueous solution of PVA during formulation of nanoparticles by a modified solid/oil/water emulsion solvent evaporation method. The non-covalent insertion of BS3 was confirmed by Fourier transform infrared (FTIR) spectroscopy. Curcumin and annexin A2 were used as a model drug and a cell specific target, respectively. Nanoparticles were characterized for particle size, zeta potential and surface morphology. The qualitative assessment of antibody attachment was performed by transmission electron microscopy (TEM) as well as confocal microscopy. The optimized formulation showed antibody attachment of 86%. However, antibody attachment was abolished upon blocking the functional groups of BS3. The availability of functional antibodies was evaluated by the presence of a light chain fraction after gel electrophoresis. We further evaluated the in vitro release kinetics of curcumin from antibody coated and uncoated nanoparticles. The release of curcumin is enhanced upon antibody attachment and followed an anomalous release pattern. We also observed that the cellular uptake of nanoparticles was significantly higher in annexin A2 positive cells than in negative cells. Therefore, these results demonstrate the potential use of this method for functionalization as well as to deliver chemotherapeutic agents for treating cancer.


Asunto(s)
Reactivos de Enlaces Cruzados/química , Sistemas de Liberación de Medicamentos/métodos , Ácido Láctico/química , Nanopartículas/química , Neoplasias/terapia , Ácido Poliglicólico/química , Succinimidas/química , Anticuerpos/inmunología , Línea Celular Tumoral , Curcumina/farmacología , Humanos , Cinética , Microscopía Confocal , Nanopartículas/ultraestructura , Tamaño de la Partícula , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie/efectos de los fármacos
13.
Pharmeur Bio Sci Notes ; 2021: 88-100, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33973517

RESUMEN

The European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) for human coagulation Factor VIII (FVIII) Concentrate is used as working standard for potency determination of human coagulation FVIII preparations by chromogenic assay. BRP batch 5 was established in 2015 and its stocks were running low. Therefore, the European Directorate for the Quality of Medicines & HealthCare (EDQM) initiated a project (BSP156) for the calibration of a replacement batch. The potency of BRP batch 6 was assigned during an international collaborative study involving 16 laboratories worldwide, with reference to the WHO 8th International Standard (IS) and BRP batch 5. Participants were instructed to perform 3 independent FVIII potency assays following their own routine validated methods for the chromogenic assay, which is the assay prescribed by the Ph. Eur. As an outcome of the study, Ph. Eur. human coagulation FVIII Concentrate BRP batch 6 was assigned a consensus potency of 9.9 IU/ampoule for the chromogenic assay. The Ph. Eur. BRP batch 6 is a freeze-dried, plasma-derived concentrate. Based on accelerated degradation studies, the stability of the material is suitable for a reference preparation. The Ph. Eur. BRP batch 6 was adopted at the 167th session of the Ph. Eur. Commission in June 2020 and is available from the EDQM under product code H0920000.


Asunto(s)
Factor VIII , Laboratorios , Calibración , Europa (Continente) , Liofilización , Humanos , Estándares de Referencia
14.
J Ethnopharmacol ; 274: 113304, 2021 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-32920131

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Withania somnifera (L.) Dunal (WS), a known'Rasayana' (rejuvenating agent) as per Ayurveda is prescribed to promote health, to increase longevity and to hasten recovery in disease convalescent stages. WS has demonstrated protective effect on alcohol dependence and withdrawal anxiety in previous experimental studies. AIM OF THE STUDY: To evaluate effect of WS on conditioned place behavioral paradigm (model of relapse) and on GABA and dopamine levels in critical brain areas in alcohol dependent animals. METHODOLOGY: Following Animal Ethics Committee permission, the mice (n = 24) were divided into the following study groups for experiment 1: 1 -distilled water (vehicle control), 2 -WS and 3 -Naltrexone. They were conditioned on conditioned place preference (CPP) using alcohol (2 gm/kg)/saline (1 ml) administered intraperitoneally for 8 days. WS and Naltrexone were administered during the period of extinction (6-8 days). Effect of WS (650 mg/kg) on reinstating behaviour of mice (time spent in alcohol paired compartment) primed with alcohol injection was noted. In experiment 2, effect of WS (450 mg/kg/) on GABA and dopamine levels in the midbrain, striatum and cortex (ng/gm) were measured in alcohol dependent rats (n = 24) following the first phase of standardisation assay (n = 36). The rats were made alcohol dependent for 15 days (intermittent access model) and WS was administered concurrently. GABA and dopamine levels were measured on Day 16. RESULTS: WS group showed decrease in time spent in alcohol paired compartment alike Naltrexone and it differed significantly compared to the distilled water control group (p < 0.05) Alcohol-dependent rats showed significant decrease in GABA and increase in dopamine levels vs distilled water in the midbrain, striatum and cortex. WS and Naltrexone administration showed rise in GABA and fall in dopamine in all the isolated brain parts in the respective groups (p < 0.05 vs alcohol treated group). CONCLUSION: Withania somnifera protected animals from relapse and showed beneficial effects on the brain neurotransmitters involved in alcohol dependence. The study provides substantial evidence for its potential application in alcohol use disorder.


Asunto(s)
Alcoholismo/tratamiento farmacológico , Dopamina/metabolismo , Extractos Vegetales/farmacología , Raíces de Plantas/química , Withania/química , Ácido gamma-Aminobutírico/metabolismo , Alcoholismo/metabolismo , Animales , Conducta Animal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Femenino , Masculino , Medicina Ayurvédica , Ratones , Naltrexona/farmacología , Naltrexona/uso terapéutico , Extractos Vegetales/uso terapéutico , Ratas Wistar
15.
Nanotechnology ; 21(39): 395102, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-20820096

RESUMEN

This work reports the targeting of the near infrared (NIR) dye indocyanine green (ICG) to the brain using composite nanoparticles. Thermal decomposition of iron pentacarbonyl was used to synthesize monodisperse oleic acid coated magnetic nanoparticles (OAMNP). Synthesized OAMNP and ICG were encapsulated in a poly (lactide-co-glycolide) matrix using an emulsion evaporation method. Different batches containing OAMNP:PLGA ratios (1:4, 1:2 and 3:4) were prepared with ICG (group B-1, 2, 3) and without ICG (group A-1, 2, 3) loading. All the formulations were characterized in terms of morphology, particle size, zeta potential, magnetic content, ICG encapsulation efficiency and the spectral properties of ICG. The optimized formulation showed an encapsulation efficiency of 56 +/- 4.6% for ICG and 57 +/- 1.37% for OAMNP. The biodistribution and brain targeting study involved three groups of six animals, each with 0.4 mg kg(-1) equivalent of ICG, given as neat ICG solution, composite nanoparticles without the aid of a magnetic field, and composite nanoparticles under the influence of a magnetic field (8000 G) to groups 1, 2 and 3 respectively. The tissue analysis and microscopy images revealed a significantly higher brain concentration of ICG (p < 0.05) for group 3 than the two control groups. These results are encouraging for the brain delivery of hydrophilic dyes/drugs using this method for biomedical applications.


Asunto(s)
Química Encefálica , Medios de Contraste , Verde de Indocianina , Nanopartículas de Magnetita/química , Nanocompuestos/química , Espectroscopía Infrarroja Corta/métodos , Análisis de Varianza , Animales , Encéfalo , Medios de Contraste/química , Medios de Contraste/farmacocinética , Sistemas de Liberación de Medicamentos , Histocitoquímica , Verde de Indocianina/química , Verde de Indocianina/farmacocinética , Ácido Láctico , Microscopía Electrónica de Transmisión , Microscopía Fluorescente , Ácido Oléico , Tamaño de la Partícula , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas , Ratas Sprague-Dawley , Espectroscopía Infrarroja por Transformada de Fourier
16.
Int J Pharm ; 535(1-2): 27-37, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-29054821

RESUMEN

The compliance of patients to solid oral dosage forms is strongly conditioned by the perceived ease of swallowing, especially in geriatric and pediatric populations. This study proposes a method, based on an in vitro model of the human oropharyngeal cavity, to study quantitatively the oral phase of human swallowing in presence of single or multiple tablets. The dynamics of swallowing was investigated varying the size and shape of model tablets and adjusting the force applied to the mechanical setup to simulate tongue pressure variations among individuals. The evolution of the velocity of the bolus, the oral transit time, and the relative position of the solid oral dosage form within the liquid bolus were measured quantitatively from high speed camera recordings. Whenever the solid dosage forms were big enough to interact with the walls of the in vitro oral cavity, a strong effect of the volume of the medication in respect of its swallowing velocity was observed, with elongated tablets flowing faster than spherical tablets. Conversely, the geometrical properties of the solid oral dosage forms did not significantly affect the bolus dynamics when the cross section of the tablet was lower than 40% of that of the bolus. The oral phase of swallowing multiple tablets was also considered in the study by comparing different sizes while maintaining a constant total mass. The predictive power of different theories was also evaluated against the experimental results, providing a mechanistic interpretation of the dynamics of the in vitro oral phase of swallowing. These findings and this approach could pave the way for a better design of solid oral medications to address the special needs of children or patients with swallowing disorders and could help designing more successful sensory evaluations and clinical studies.


Asunto(s)
Trastornos de Deglución/fisiopatología , Deglución/fisiología , Modelos Biológicos , Boca/fisiología , Comprimidos/administración & dosificación , Comprimidos/química , Cápsulas/administración & dosificación , Cápsulas/química , Humanos , Boca/anatomía & histología , Propiedades de Superficie
17.
J Thromb Haemost ; 5(9): 1923-9, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17723131

RESUMEN

BACKGROUND: An international collaborative study, involving 23 laboratories, was carried out, under the auspices of the FXIII Standardization Working Party (SWP), to calibrate the 1st International Standard (IS) for factor XIII (FXIII) plasma. METHODS: Potency estimates for the proposed candidate FXIII plasma (preparation Y: NIBSC code 02/206) were calculated relative to locally collected normal plasma pools (pool N), for both FXIII activity and antigen levels. RESULTS: Estimates of FXIII activity potency for preparation Y showed good agreement between laboratories, with an interlaboratory geometric coefficient of variation (GCV) of 11.5% and a mean value of 0.91 U mL(-1). Furthermore, there was a negligible difference in potencies by two commercially available methods, the potencies differing only by approximately 1%. Estimates of FXIII antigen (A(2)B(2) complex) potency for preparation Y showed good agreement between laboratories, with an interlaboratory GCV of 16.3% and a mean value of 0.93 U mL(-1). Accelerated degradation studies showed that the proposed standard is very stable, with a predicted loss of activity (and antigen) per year of< 0.06% at the recommended storage temperature of -20 degrees C. CONCLUSIONS: The suitability and potency of preparation Y were considered by the participants, members of the ISTH/SSC FXIII Subcommittee, the Scientific and Standardization Committee and the SWP. Following their approval, preparation Y was proposed to and accepted by the Expert Committee on Biological Standardization of the World Health Organization to be the 1st IS for FXIII plasma with an activity potency of 0.91 IU per ampoule and an antigen potency of 0.93 IU per ampoule.


Asunto(s)
Factor XIII/normas , Plasma , Conducta Cooperativa , Factor XIII/inmunología , Humanos , Laboratorios , Reproducibilidad de los Resultados
18.
Pharmeur Bio Sci Notes ; 2017: 1-11, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28279252

RESUMEN

The European Pharmacopoeia Biological Reference Preparation (Ph. Eur. BRP) for Factor VIII Concentrate batch 5 was established through a collaborative study involving 14 laboratories organised by the European Directorate for the Quality of Medicines & HealthCare (EDQM, Council of Europe) to be used as working standard for potency determination of human coagulation Factor VIII (FVIII) preparations. The potency of the BRP batch 5 was assigned with reference to the WHO 8th International Standard (IS) for FVIII Concentrate and the BRP batch 4. Participants were instructed to perform 3 independent Factor VIII potency assays following their own routine validated methods by the chromogenic assay as it is the assay prescribed by the European Pharmacopoeia. This publication reports the results obtained during the study. The consensus potency, 9.9 IU/ampoule (n = 14) when assessed against both standards, with inter-laboratory geometric coefficients of variation (GCV) of 3.2 % and 1.9 % against the WHO 8th IS and the BRP batch 4 respectively, was consistent with the expected value. The Ph. Eur. BRP batch 5 is a freeze-dried, plasma-derived concentrate. Based on accelerated degradation studies, the stability of the material is suitable as a reference preparation. The Ph. Eur. BRP batch 5 was adopted at the 151st session of the European Pharmacopoeia Commission in March 2015 and is available from the EDQM.


Asunto(s)
Química Farmacéutica/normas , Factor VIII/análisis , Factor VIII/normas , Farmacopeas como Asunto/normas , Calibración/normas , Química Farmacéutica/métodos , Europa (Continente) , Humanos
19.
J Thromb Haemost ; 3(1): 119-26, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15634275

RESUMEN

A candidate concentrate, preparation N (99/678), was assayed and calibrated, as a potential replacement, against four established factor (F) VIII concentrate standards: the current WHO 6th International Standard (IS) (97/616), the previous 5th IS (88/640), the Mega 1 standard and Ph. Eur. BRP Batch 2 standard, in a collaborative study involving 38 laboratories. All laboratories were instructed to use the ISTH/SSC recommendations, including predilution of concentrates in FVIII-deficient plasma. Several laboratories performed more than one assay method and altogether there were 27 sets of assays with the one-stage method, 31 with the chromogenic method, and 18 with both methods. There was good agreement between laboratories using each of the two methods for comparison of preparation N against the four established standards, with overall potencies by one-stage and chromogenic methods differing only by less than 2%. However, there were significant differences in potencies relative to the different standards, ranging from 10.1 IU per ampoule against the Ph. Eur.BRP2 to 11.4 against the WHO 6th IS. Accelerated degradation studies showed that the proposed standard is very stable, with a predicted loss of activity per year of less than 0.001% at the recommended storage temperature of -20 degrees C. Various options for potency of preparation N were considered by the participants and by members of the ISTH/SSC FVIII/FIX Subcommittee. In November 2003, preparation N (NIBSC 99/678) was proposed to and accepted by the Expert Committee on Biological Standardization of the World Health Organization to be the 7th International Standard for Factor VIII Concentrate with an assigned potency of 11.0 IU per ampoule.


Asunto(s)
Química Clínica/métodos , Factor VIII/normas , Calibración , Estabilidad de Medicamentos , Humanos , Cooperación Internacional , Laboratorios/normas , Proteínas Recombinantes/análisis , Proteínas Recombinantes/normas , Estándares de Referencia , Reproducibilidad de los Resultados , Temperatura , Organización Mundial de la Salud
20.
Virusdisease ; 26(1-2): 70-6, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26436124

RESUMEN

Classical swine fever virus (CSFV), the causative agent of classical swine fever, belongs to the family Flaviviridae and genus Pestivirus. Some pestiviruses exhibit cytopathic effect in cell culture but exact phenomenon is unknown. Over expression of NS2-3 gene, presence of defective interfering particle and exaltation of Newcastle disease virus (END) phenomenon could be the reasons of cytopathogenicity. In the present study, a CSFV isolate exhibiting cytopathic effect (CPE) in Madin-Darby Canine Kidney (MDCK) cell line was characterized. To characterize cytopathogenicity of such isolate, END test was carried out. Interference of Newcastle disease virus (NDV) in MDCK adapted CSFV was confirmed by RT-PCR and virus neutralization test. Absence of CPE and NDV specific nucleic acid after neutralization confirmed the induction of CPE by NDV. Further, identity of the CSFV isolate in MDCK cell line by immunoperoxidase test, immunoblotting and RT-PCR post NDV neutralization established the virus replication without CPE (non-cytopathic isolate). Findings suggest that, there could be a chance of mixed infection of both CSFV and NDV in the piglet from which the sample was collected for virus isolation.

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