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1.
PLoS One ; 17(12): e0278103, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36580459

RESUMEN

INTRODUCTION: Ursolic acid (UA) and oleanolic acid (OA) are triterpenoids. They are used to treat numerous diseases, including tuberculosis. Combinations of these drugs provide new insight into the management of tuberculosis. The major obstacle is the effective delivery of these drugs to the lungs, which are mainly affected due to M. tuberculosis. A metered-dose inhaler (MDI) was developed to address this issue containing UA and OA, followed by in-vitro and in-vivo evaluation. METHODS: In the present study, MDI formulation was prepared by incorporating UA and OA at the dose level of 120 µg/ml in each actuation. In-vitro evaluation of this MDI formulation was performed to ensure its suitability to deliver UA and OA preciously. With prior approval of IAEC, a pharmacokinetic and acute inhalation toxicity study was conducted using MDI on Wistar rats. RESULTS: The pharmacokinetic study showed an increased biological half-life of UA (9.23±0.104 h) and OA (8.93±0.166 h) in combination therapy. In-vivo toxicity study demonstrated no adverse effects on body weight and vital organs in the treatment group compared with the control group. Histopathology examination of these essential organs showed no abnormalities. Mild alternation in the biochemical and hematological parameters was observed. However, these alterations did not affect the overall health of the animals. CONCLUSION: The present study documents a detailed study for the safety and pharmacokinetics of UA and OA in-vivo for their advanced application in tuberculosis disease.


Asunto(s)
Mycobacterium tuberculosis , Ácido Oleanólico , Triterpenos , Tuberculosis , Ratas , Animales , Ácido Oleanólico/toxicidad , Ratas Wistar , Pulmón , Nebulizadores y Vaporizadores , Triterpenos/toxicidad , Ácido Ursólico
2.
J Neural Eng ; 19(6)2022 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-36270485

RESUMEN

Objective.Clinical diagnosis of epilepsy relies partially on identifying interictal epileptiform discharges (IEDs) in scalp electroencephalograms (EEGs). This process is expert-biased, tedious, and can delay the diagnosis procedure. Beyond automatically detecting IEDs, there are far fewer studies on automated methods to differentiate epileptic EEGs (potentially without IEDs) from normal EEGs. In addition, the diagnosis of epilepsy based on a single EEG tends to be low. Consequently, there is a strong need for automated systems for EEG interpretation. Traditionally, epilepsy diagnosis relies heavily on IEDs. However, since not all epileptic EEGs exhibit IEDs, it is essential to explore IED-independent EEG measures for epilepsy diagnosis. The main objective is to develop an automated system for detecting epileptic EEGs, both with or without IEDs. In order to detect epileptic EEGs without IEDs, it is crucial to include EEG features in the algorithm that are not directly related to IEDs.Approach.In this study, we explore the background characteristics of interictal EEG for automated and more reliable diagnosis of epilepsy. Specifically, we investigate features based on univariate temporal measures (UTMs), spectral, wavelet, Stockwell, connectivity, and graph metrics of EEGs, besides patient-related information (age and vigilance state). The evaluation is performed on a sizeable cohort of routine scalp EEGs (685 epileptic EEGs and 1229 normal EEGs) from five centers across Singapore, USA, and India.Main results.In comparison with the current literature, we obtained an improved Leave-One-Subject-Out (LOSO) cross-validation (CV) area under the curve (AUC) of 0.871 (Balanced Accuracy (BAC) of 80.9%) with a combination of three features (IED rate, and Daubechies and Morlet wavelets) for the classification of EEGs with IEDs vs. normal EEGs. The IED-independent feature UTM achieved a LOSO CV AUC of 0.809 (BAC of 74.4%). The inclusion of IED-independent features also helps to improve the EEG-level classification of epileptic EEGs with and without IEDs vs. normal EEGs, achieving an AUC of 0.822 (BAC of 77.6%) compared to 0.688 (BAC of 59.6%) for classification only based on the IED rate. Specifically, the addition of IED-independent features improved the BAC by 21% in detecting epileptic EEGs that do not contain IEDs.Significance.These results pave the way towards automated detection of epilepsy. We are one of the first to analyze epileptic EEGs without IEDs, thereby opening up an underexplored option in epilepsy diagnosis.


Asunto(s)
Electroencefalografía , Epilepsia , Humanos , Electroencefalografía/métodos , Epilepsia/diagnóstico
3.
ACS Appl Mater Interfaces ; 13(32): 38844-38856, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34352173

RESUMEN

In this work, carbonaceous nanoparticles (NPs) of varying morphology, viz., multilayer graphene (lamellar, thickness ∼ 3-7 nm), graphite (spherical ∼70 nm), and multi-walled carbon nanotubes (tubular), were selected to explore their tribo-potential in oil under identical operating conditions. A series of nano-oils were prepared using API group III mineral base oil with a dispersant (1%) and selected NPs in incremental concentration (0.5-4%). The tribo-performance of oils was evaluated on a four-ball tester and SRV-IV for extreme-pressure, antiwear (AW), and antifriction performance. Formulations were characterized for density, viscosity, and viscosity index. The stability of oils was monitored through visual observation weekly. Results revealed that the graphene particles showed excellent wear-preventive ability as an AW additive with (41-50) % increase followed by nanographite. Worn surfaces were studied to understand the plausible wear mechanism using a different spectroscopic technique. Tribo-behavior performance was supported with lateral force microscopy on the surfaces of tribo-films.

4.
Int J Neural Syst ; 31(8): 2150032, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34278972

RESUMEN

Epilepsy diagnosis based on Interictal Epileptiform Discharges (IEDs) in scalp electroencephalograms (EEGs) is laborious and often subjective. Therefore, it is necessary to build an effective IED detector and an automatic method to classify IED-free versus IED EEGs. In this study, we evaluate features that may provide reliable IED detection and EEG classification. Specifically, we investigate the IED detector based on convolutional neural network (ConvNet) with different input features (temporal, spectral, and wavelet features). We explore different ConvNet architectures and types, including 1D (one-dimensional) ConvNet, 2D (two-dimensional) ConvNet, and noise injection at various layers. We evaluate the EEG classification performance on five independent datasets. The 1D ConvNet with preprocessed full-frequency EEG signal and frequency bands (delta, theta, alpha, beta) with Gaussian additive noise at the output layer achieved the best IED detection results with a false detection rate of 0.23/min at 90% sensitivity. The EEG classification system obtained a mean EEG classification Leave-One-Institution-Out (LOIO) cross-validation (CV) balanced accuracy (BAC) of 78.1% (area under the curve (AUC) of 0.839) and Leave-One-Subject-Out (LOSO) CV BAC of 79.5% (AUC of 0.856). Since the proposed classification system only takes a few seconds to analyze a 30-min routine EEG, it may help in reducing the human effort required for epilepsy diagnosis.


Asunto(s)
Aprendizaje Profundo , Epilepsia , Electroencefalografía , Epilepsia/diagnóstico , Humanos , Redes Neurales de la Computación , Cuero Cabelludo
5.
Int J Neural Syst ; 31(6): 2150016, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33775230

RESUMEN

Pathological slowing in the electroencephalogram (EEG) is widely investigated for the diagnosis of neurological disorders. Currently, the gold standard for slowing detection is the visual inspection of the EEG by experts, which is time-consuming and subjective. To address those issues, we propose three automated approaches to detect slowing in EEG: Threshold-based Detection System (TDS), Shallow Learning-based Detection System (SLDS), and Deep Learning-based Detection System (DLDS). These systems are evaluated on channel-, segment-, and EEG-level. The three systems perform prediction via detecting slowing at individual channels, and those detections are arranged in histograms for detection of slowing at the segment- and EEG-level. We evaluate the systems through Leave-One-Subject-Out (LOSO) cross-validation (CV) and Leave-One-Institution-Out (LOIO) CV on four datasets from the US, Singapore, and India. The DLDS achieved the best overall results: LOIO CV mean balanced accuracy (BAC) of 71.9%, 75.5%, and 82.0% at channel-, segment- and EEG-level, and LOSO CV mean BAC of 73.6%, 77.2%, and 81.8% at channel-, segment-, and EEG-level. The channel- and segment-level performance is comparable to the intra-rater agreement (IRA) of an expert of 72.4% and 82%. The DLDS can process a 30 min EEG in 4 s and can be deployed to assist clinicians in interpreting EEGs.


Asunto(s)
Epilepsia , Procesamiento de Señales Asistido por Computador , Adulto , Electroencefalografía , Humanos , Cuero Cabelludo
6.
Int J Neural Syst ; 31(5): 2050074, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33438530

RESUMEN

The diagnosis of epilepsy often relies on a reading of routine scalp electroencephalograms (EEGs). Since seizures are highly unlikely to be detected in a routine scalp EEG, the primary diagnosis depends heavily on the visual evaluation of Interictal Epileptiform Discharges (IEDs). This process is tedious, expert-centered, and delays the treatment plan. Consequently, the development of an automated, fast, and reliable epileptic EEG diagnostic system is essential. In this study, we propose a system to classify EEG as epileptic or normal based on multiple modalities extracted from the interictal EEG. The ensemble system consists of three components: a Convolutional Neural Network (CNN)-based IED detector, a Template Matching (TM)-based IED detector, and a spectral feature-based classifier. We evaluate the system on datasets from six centers from the USA, Singapore, and India. The system yields a mean Leave-One-Institution-Out (LOIO) cross-validation (CV) area under curve (AUC) of 0.826 (balanced accuracy (BAC) of 76.1%) and Leave-One-Subject-Out (LOSO) CV AUC of 0.812 (BAC of 74.8%). The LOIO results are found to be similar to the interrater agreement (IRA) reported in the literature for epileptic EEG classification. Moreover, as the proposed system can process routine EEGs in a few seconds, it may aid the clinicians in diagnosing epilepsy efficiently.


Asunto(s)
Epilepsia , Cuero Cabelludo , Adulto , Electroencefalografía , Epilepsia/diagnóstico , Humanos , Redes Neurales de la Computación , Convulsiones
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3703-3706, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33018805

RESUMEN

Epilepsy diagnosis through visual examination of interictal epileptiform discharges (IEDs) in scalp electroencephalogram (EEG) signals is a challenging problem. Deep learning methods can be an automated way to perform this task. In this work, we present a new approach based on convolutional neural network (CNN) to detect IEDs from EEGs automatically. The input to CNN is a combination of raw EEG and frequency sub-bands, namely delta, theta, alpha and, beta arranged as a vector for one-dimensional (1D) CNN or matrix for two-dimensional (2D) CNN. The proposed method is evaluated on 554 scalp EEGs. The database consists of 18,164 IEDs marked by two neurologists. Five-fold cross-validation was performed to assess the IED detectors. The resulting 1D CNN based IED detector with multiple sub-bands achieved a false positive rate per minute of 0.23 and a precision of 0.79 at 90% sensitivity. Further, the proposed system is evaluated on datasets from three other clinics, and the features extracted from CNN outputs could significantly discriminate (p-values <; 0.05) the EEGs with and without IEDs. We have proposed an optimized method with better performance than the literature that could aid clinicians to diagnose epilepsy expeditiously, and thereby devise proper treatment.


Asunto(s)
Aprendizaje Profundo , Epilepsia , Electroencefalografía , Epilepsia/diagnóstico , Humanos , Redes Neurales de la Computación , Cuero Cabelludo
8.
Wilderness Environ Med ; 31(2): 220-225, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32173212

RESUMEN

A case of midget-faded rattlesnake (Crotalus oreganus concolor) envenomation of an adult male professional herpetologist occurred in a rural setting and resulted in an array of venom induced myoneurologic symptoms. The patient experienced blurry vision, total body paresthesia, dyspnea, chest tightness, and waves of spastic muscle movements of the hands and feet that resembled tetany. It was not apparent whether these symptoms were potentially venom induced or were related to stress-induced physiologic responses. Local envenomation effects were minimal, and coagulation parameters remained within normal limits. Antivenom was not administered per patient concerns related to a history of acute allergic reactions to antivenom. Venom was collected from the Crotalus oreganus concolor responsible for the bite, and analysis revealed the presence of high levels of myotoxins (SR calcium pump antagonists) and concolor toxin, a presynaptic neurotoxin that can have myotoxic effects and cause respiratory paralysis; several serine proteinases associated with coagulopathies were also present in the venom profile.


Asunto(s)
Venenos de Crotálidos/efectos adversos , Crotalus , Mialgia/terapia , Mordeduras de Serpientes/complicaciones , Animales , Venenos de Crotálidos/análisis , Humanos , Masculino , Persona de Mediana Edad , Mialgia/inducido químicamente , Mialgia/diagnóstico , Resultado del Tratamiento
9.
Biomed Phys Eng Express ; 6(6)2020 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-35046148

RESUMEN

Dosimetry of small fields (SF) is vital for the success of highly conformal techniques. IAEA along with AAPM recently published a code of practice TRS-483 for SF dosimetry. The scope of this paper is to investigate the performance of three different detectors with 10 MV with-flatting-filter (WFF) beam using TRS-483 for SF dosimetry and subsequent commissioning of the Eclipse treatment planning system (TPS version-13.6) for SF data. SF dosimetry data (beam-quality TPR20,10(10), cross-calibration, beam-profile, and field-output-factor(F.O.F)) measurements were performed for PTW31006-pinpoint, IBA-CC01 and IBA-EFD-3G diode detectors in nominal field size (F.S) range 0.5 × 0.5cm2to 10 × 10 cm2with water and solid water medium using Varian Truebeam linac. However, Eclipse-TPS commissioning data was acquired using IBA-EFD-3G diode, and absolute dose calibration was performed with FC-65G detector. The dosimetric performance of the Eclipse-TPS was validated using TLD-LiF chips, IBA-PFD, and IBA-EFD-3G diodes. Dosimetric performance of the PTW31006-pinpoint, IBA-CC01, and IBA-EFD-3G detectors was successfully tested for SF dosimetry. The F.O.Fs were generated and found in close agreement for all F.S except 0.5 × 0.5cm2. It is also found that TPR20,10(10) value can be derived within 0.5% accuracy from a non-reference field using Palmans equation. Cross-calibration can be performed in F.S 6 × 6 cm2with a maximum variation of 0.5% with respect to 10 × 10cm2. During profile measurement, the full-width half-maxima (FWHM) of F.S 0.5 × 0.5cm2was found maximum deviated from the geometric F.S. In addition, Eclipse-TPS was commissioned along with some limitations: F.O.F below F.S 1 × 1cm2was ignored by TPS, PDD and profiles were dropped from configuration below F.S 2 × 2 cm2, and F.O.F which does not satisfy the condition 0.7 < A/B < 1.4 (A and B are FWHM in cross-line and in-line direction) have higher uncertainty than specified in TRS-483. Validation tests for Eclipse-TPS generated plans were also performed. The measured dose was in close agreement (3%) with TPS calculated dose up to F.S 1.5 × 1.5cm2.


Asunto(s)
Fotones , Radiometría , Calibración , Aceleradores de Partículas , Fotones/uso terapéutico , Incertidumbre
10.
J Ethn Subst Abuse ; 18(3): 345-358, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-28898165

RESUMEN

Internalized stigma among individuals with substance use disorders is a major barrier for accessing mental health services. This study aimed to assess internalized stigma among individuals with substance use disorders and to assess the relationship of internalized stigma with the quality of life. This cross-sectional study recruited 201 patients with a clinical diagnosis of at least opioid or alcohol use disorder according to Diagnostic and Statistical Manual 5 at a public-funded tertiary care center in India. The study participants were interviewed using a sociodemographic questionnaire, the Internalized Stigma of Mental Illness Scale (ISMIS), and the World Health Organization's Quality of Life (WHOQOL-Bref) questionnaire. Seven participants (3.5% of the sample) had mild stigma according to ISMI scores, 62 (30.8%) had moderate stigma, and 132 (65.7%) had severe stigma. The various quality-of-life domains generally had a negative correlation with the internalized stigma scores. Participants using opioids as the primary substance of use were more likely to have severe internalized stigma. The experience of internalized stigma and dissatisfaction with quality of life is quite high among people suffering with substance use disorders in India. These results emphasize the need for interventions to reduce internal perception of stigma and improve the quality of life of individuals with substance use disorders.


Asunto(s)
Alcoholismo/psicología , Trastornos Relacionados con Opioides/psicología , Calidad de Vida , Estigma Social , Adolescente , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , Trastornos Relacionados con Sustancias/psicología , Encuestas y Cuestionarios , Centros de Atención Terciaria , Adulto Joven
11.
Biomed Res Int ; 2014: 876182, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25050376

RESUMEN

The present investigation deals with the optimization, formulation, and characterization of oral in situ gel of spiramycin. Sodium alginate and hydroxypropyl methylcellulose were used as cross-linking and viscosifying agents, respectively. Sodium bicarbonate was used as a floating agent. In preformulation studies, the melting point, pH, and partition coefficient were found to be 133 °C, 9.5, and 0.193, respectively. The drug had retention time at around 2.65 minutes in high performance liquid chromatography (HPLC). During compatibility studies of drug with all polymers, we observed that there were no changes in the FTIR spectra of a mixture of drug and polymers. All the formulations showed good pourability. Floating time and total floating time were ~30 sec and >12 hours, respectively. During in vitro drug release studies, the drug was released from the formulation around 80-100% for 12-16 hrs. In TEM analysis, we found that the drug molecules were well entrapped in the polymer and the drug was released slowly for up to 12 hrs. In these studies, we found that the concentration of sodium alginate and HPMC had significant influence on floating lag time, gelling capacity, and cumulative percentage drug release. During antimicrobial studies, we found that the formulation containing spiramycin showed good zone of inhibition against different microbial strains (Staphylococcus aureus and Escherichia coli).


Asunto(s)
Geles/farmacología , Espiramicina/farmacología , Administración Oral , Cromatografía Líquida de Alta Presión , Escherichia coli/efectos de los fármacos , Concentración de Iones de Hidrógeno , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Transmisión , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Viscosidad
12.
ScientificWorldJournal ; 2014: 560962, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24592173

RESUMEN

Gemcitabine (2,2-difluorodeoxycytidine) is a deoxycytidine analog, currently being used as a first-choice drug in pancreatic metastatic cancer. Gemcitabine is administered weekly as 30-minute infusion with starting dose ranging from 800 to 1250 mg/m(2). The aim of the present work was to develop starch nanoparticles (NPs) for the delivery of gemcitabine hydrochloride that could reduce its dose related side effects and may prolong its retention time (24 hrs) for the treatment of pancreatic cancer. Nanoparticles were prepared by emulsification diffusion method with slight modifications. Size and morphology of nanoparticles were investigated. Particles were spherical in shape with slightly rough surfaces. Particle size and polydispersity index were 231.4 nm and 1.0, respectively while zeta potential of blank NPs and drug loaded NPs were found to be -11.8 mV and -9.55 mV, respectively. Percent entrapment efficiency of different formulations was around ∼ 54% to 65%. In vitro release profile studies showed that around 70%-83% of drug was released from different formulations. Anticancerous cell line studies were also performed in human pancreatic cell lines (MIA-PA-CA-2).


Asunto(s)
Desoxicitidina/análogos & derivados , Portadores de Fármacos/farmacología , Nanopartículas/química , Línea Celular Tumoral , Desoxicitidina/química , Desoxicitidina/farmacología , Portadores de Fármacos/química , Hepatocitos/efectos de los fármacos , Humanos , Concentración 50 Inhibidora , Almidón/química , Gemcitabina
13.
Drug Deliv ; 21(3): 233-41, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24171405

RESUMEN

CONTEXT: In our recent studies, Brugia malayi molecules have shown interesting immune-stimulating and immune-suppressive properties. Among these, F6 a pro-inflammatory (54-68 kDa) SDS-PAGE resolved fraction of the parasite when administered with Freund's complete/incomplete adjuvant in animals, elicited both Th1 and Th2 type immune responses and protects the host from filarial parasite. OBJECTIVE: The present study was aimed at developing biodegradable microspheres for filarial antigenic protein molecules and to investigate the immunoadjuvanticity of microspheres (Ms)-loaded F6 molecules. MATERIALS AND METHODS: Poly-lactide microspheres (DL-PLA-Ms) were prepared using double emulsification and solvent evaporation method; and studied their size, shape, antigen adsorption efficiency, in-process stability, and antigen release profiles. F6 and B. malayi adult worm (BmA: ∼ 17 to 180 kDa) protein molecules adsorbed on the Ms were administered in a single shot into Swiss mice, subcutaneously, and investigated their immunoadjuvant effect and compared with one/two doses-schedule of plain F6/BmA. RESULTS: Immunization with F6/BmA-loaded DL-PLA-Ms resulted in upregulation of cellular proliferation, IFN- γ, TNF-α and NO release from host's cells stimulated with F6/BmA or LPS/Con A, IgG, IgG1 and IgG2a levels. These responses were well comparable with the responses produced by two doses of plain BmA/F6. DISCUSSION AND CONCLUSION: In conclusion, a single dose of DL-PLA-Ms-F6 induced predominantly Th1 immune responses and well comparable with two doses of plain F6. This is the first ever report on potential of DL-PLA-Ms as adjuvant for filarial immunogen.


Asunto(s)
Adyuvantes Inmunológicos , Antígenos Helmínticos/inmunología , Brugia Malayi/inmunología , Inmunidad Celular/efectos de los fármacos , Inmunidad Humoral/efectos de los fármacos , Poliésteres , Vacunas/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/química , Animales , Anticuerpos Antihelmínticos/sangre , Antígenos Helmínticos/administración & dosificación , Antígenos Helmínticos/química , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Química Farmacéutica , Inmunización , Inyecciones Subcutáneas , Interferón gamma/metabolismo , Activación de Linfocitos/efectos de los fármacos , Ratones , Microesferas , Óxido Nítrico/metabolismo , Tamaño de la Partícula , Poliésteres/administración & dosificación , Poliésteres/química , Factores de Tiempo , Factor de Necrosis Tumoral alfa/metabolismo , Vacunas/administración & dosificación , Vacunas/química
14.
Curr Pharm Biotechnol ; 14(6): 594-614, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24016268

RESUMEN

Edible plant vaccines are immunogenic preparations containing antigenic proteins rather than pathogens, therefore, they sanctify situation where there is a possibility of resurgence of disease when the antigenic preparation contains the organism in any form whatsoever. Expression of antigens as vaccines and of antibodies against antigens of pathogens in transgenic plants is a convenient and inexpensive source for various bacterial, viral, helminths, protozoan and autoimmune diseases with lower capital costs. This review describes various diseases along with the production of edible transgenic plant vaccines/proteins for the same. Thus, substituting and improvising conventional immunization methods.


Asunto(s)
Plantas Modificadas Genéticamente/inmunología , Vacunas Comestibles , Animales , Antígenos de Plantas/inmunología , Humanos
15.
Vaccine ; 31(38): 4183-91, 2013 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-23827312

RESUMEN

Recently we identified in Brugia malayi adult worm extract (BmA) a pro-inflammatory 54-68kDa SDS-PAGE resolved fraction F6 that protects the host from the parasite via Th1/Th2 type responses. We are currently investigating F6 as a potential source of vaccine candidate(s) and the present study is aimed at investigating the suitability of poly(d,l)-lactide-co-glycolide microspheres (PLGA-Ms) as immunoadjuvant for the antigen administration in a single dose. PLGA-Ms were prepared aseptically by a modified double emulsion (w/o/w) solvent evaporation technique and their size, shape, antigen adsorption efficiency, in-process stability, and antigen release were characterized. Swiss mice were immunized by a single subcutaneous administration of BmA and F6 adsorbed on PLGA-Ms (lactide:glycolide ratios 50:50 and 75:25) and the immune responses were compared with administration of 1 or 2 doses of plain BmA and F6. Specific IgG, IgG1, IgG2a, IgG2b, IgE levels in serum, cellular-proliferative response and release of IFN-γ, TNF-α and nitric oxide from the cells of immunized host in response to the antigens/LPS/Con A challenge and antibody-dependant cellular cytotoxicity (ADCC) to parasite life stages were determined. The average size of PLGA-Ms 50:50 was smaller than the size of PLGA-Ms 75:25 and the % antigen adsorption efficiency of PLGA-Ms 50:50 was greater than PLGA-Ms 75:25. Single shot injection of PLGA-Ms 50:50/75:25-BmA/F6 produced better and stronger IgG, IgG1/IgG2a and cell-mediated immune responses than even two injections of plain BmA or F6. Further, PLGA-Ms 50:50-F6 produced stronger responses than PLGA-Ms 50:50-BmA. Anti-PLGA-Ms 50:50-F6 antibodies elicited higher ADCC response to infective larval and microfilarial stages of the parasite than anti-PLGA-Ms 75:25-F6 antibodies. The findings demonstrate that PLGA-Ms 50:50 is an excellent adjuvant for use with F6 in a single administration. This is the first ever report on PLGA as immunoadjuvant for filarial antigens.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Antígenos de Protozoos/química , Brugia Malayi/inmunología , Ácido Láctico/inmunología , Microesferas , Vacunas Antiprotozoos/administración & dosificación , Adyuvantes Inmunológicos/química , Animales , Antígenos de Protozoos/inmunología , Proliferación Celular/efectos de los fármacos , Inmunoglobulina E/sangre , Inmunoglobulina G/sangre , Interferón gamma/metabolismo , Ácido Láctico/química , Masculino , Ratones , Óxido Nítrico/metabolismo , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Vacunas Antiprotozoos/inmunología , Vacunas Antiprotozoos/farmacología , Factor de Necrosis Tumoral alfa/metabolismo
16.
Int J Pharm ; 420(1): 101-10, 2011 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-21855618

RESUMEN

A majority of antigens require repeated administration to ensure development of adequate humoral and cell mediated immune response. To minimize the number of administrations required, we investigated the utility of biodegradable polymeric lamellar substrate particles of poly (l-lactide) (PLSP) as adjuvant for filarial antigen preparations. PLSP was prepared and characterized and Brugia malayi adult worm extract (BmA) and its SDS-PAGE resolved 54-68 kDa fraction F6 were adsorbed on to PLSP. Swiss mice received a single injection of PLSP-F6, PLSP-BmA, FCA-F6, FCA-BmA and two doses of the plain antigens. Specific IgG, IgG1, IgG2a, IgG2b and IgE levels in serum, IFN-γ, TNF-α and nitric oxide (NO) release from cells of the immunized animals in response to antigen challenge were studied. The average size of PLSP particles was <10 µm and its % antigen adsorption efficacy was 60.4, 55.2 and 61.6 for BSA, BmA and F6, respectively. Single injection of PLSP-F6 or PLSP-BmA produced better immune responses compared to one injection of FCA-F6/BmA or two injections of plain F6 or BmA. Moreover, PLSP-F6 produced much better response than PLSP-BmA. These data demonstrate for the first time that PLSP is a superior immunoadjuvant for enhancing the immune response to filarial BmA and F6 molecules and obviates the need for multiple immunization injections.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Antígenos Helmínticos/administración & dosificación , Brugia Malayi/inmunología , Portadores de Fármacos , Esquemas de Inmunización , Poliésteres/administración & dosificación , Vacunas/administración & dosificación , Adyuvantes Inmunológicos/química , Adsorción , Animales , Anticuerpos/sangre , Antígenos Helmínticos/química , Antígenos Helmínticos/inmunología , Células Cultivadas , Química Farmacéutica , Composición de Medicamentos , Estabilidad de Medicamentos , Adyuvante de Freund/administración & dosificación , Inyecciones Subcutáneas , Interferón gamma/metabolismo , Masculino , Ratones , Microscopía Electrónica de Transmisión , Óxido Nítrico/metabolismo , Tamaño de la Partícula , Poliésteres/química , Solubilidad , Bazo/inmunología , Propiedades de Superficie , Tecnología Farmacéutica/métodos , Factores de Tiempo , Factor de Necrosis Tumoral alfa/metabolismo , Vacunas/química , Vacunas/inmunología
17.
Int J Pharm ; 408(1-2): 50-7, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21291968

RESUMEN

Presently available marketed alum adsorbed hepatitis B vaccine used for prophylactic immunization, can effectively elicit humoral immunity but is poor inducer of cell-mediated immunity (CMI). Besides, conventional alum-adjuvant vaccines require multiple injections to achieve long-lasting protective immune responses. Therefore, as a result of insufficient immunization, infections are still the leading killer among diseases. The present investigation was therefore, aimed at developing "single-shot" HBsAg adsorbed microspheres of poly (DL)-lactide-co-glycolide (PLGA) (L/G 50:50 and 75:25) and their capability to stimulate the cell mediated immune response against hepatitis B surface antigen. These microspheres were characterized in vitro for their size, shape polydispersity index, percentage HBsAg adsorption efficiency and in vitro release profile. The immune-stimulating activities were also studied following subcutaneous injection of HBsAg adsorbed PLGA microspheres (single-dose on day 0) and compared with alum adsorbed vaccines (two-doses on 0 and 28 days) in Balb/c mice. Specific cell-mediated immune responses such as lymphocyte transformation assay (stimulation-index) including release of interferon-gamma (IFN-γ), interleukin-2 (IL-2) and nitric-oxide were determined. Cellular responses in case of alum adsorb HBsAg vaccine was very low. These studies demonstrate the potential of cationic polymeric microspheres based vaccine in stimulating cell mediated immune response along with humoral response against hepatitis B.


Asunto(s)
Portadores de Fármacos/química , Antígenos de la Hepatitis B/inmunología , Vacunas contra Hepatitis B/administración & dosificación , Inmunidad Celular/inmunología , Inmunidad Humoral/inmunología , Ácido Láctico/química , Ácido Poliglicólico/química , Animales , Cationes , Estabilidad de Medicamentos , Electroforesis en Gel de Poliacrilamida , Antígenos de la Hepatitis B/administración & dosificación , Antígenos de la Hepatitis B/química , Inyecciones Subcutáneas , Interferón gamma/sangre , Interferón gamma/inmunología , Interleucina-2/sangre , Interleucina-2/inmunología , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica de Rastreo , Microesferas , Peso Molecular , Óxido Nítrico/sangre , Óxido Nítrico/inmunología , Tamaño de la Partícula , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/química , Proteínas Recombinantes/inmunología , Propiedades de Superficie , Tecnología Farmacéutica
18.
J Drug Target ; 18(3): 212-22, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19883203

RESUMEN

The present investigations were aimed to compare the humoral and cell-mediated immune responses between recombinant hepatitis B surface antigens (HBsAg) adsorbed L-PLA microspheres (Ms) vaccine (single-shot) and marketed alum-HBsAg vaccine (two-doses). The blank cationic (cetyltrimethyammoniumbromide) microspheres were prepared by the double emulsion (w/o/w) solvent evaporation technique. The HBsAg was adsorbed onto the surface of blank cationic microspheres. These microspheres were characterized in vitro for their size, shape, adsorption-efficiency, in-process stability, and HBsAg release studies. Specific humoral immune responses (IgM and IgG) and cell-mediated immune responses (cellular-proliferation) assay including release of interferon-gamma (IFN-gamma), interleukin-2 (IL-2), and nitric oxide (NO) from host's cells stimulated with HBsAg or lipopolysaccharide (LPS)/ concanavalin A (con A) in-vitro were determined. Based on these findings, it was concluded that the single injection (using subcutaneous-route) of the polymeric microspheres produced better immune response (both humoral and cell-mediated) than two injections of a conventional alum-HBsAg vaccine. These data demonstrate high potential of polymeric microspheres for their use as a carrier adjuvant for hepatitis B vaccine.


Asunto(s)
Portadores de Fármacos/química , Antígenos de Superficie de la Hepatitis B/inmunología , Vacunas contra Hepatitis B/inmunología , Poliésteres/química , Animales , Cationes , Química Farmacéutica/métodos , Emulsiones , Antígenos de Superficie de la Hepatitis B/administración & dosificación , Vacunas contra Hepatitis B/administración & dosificación , Inmunidad Celular , Inmunidad Humoral , Inyecciones Subcutáneas , Masculino , Ratones , Ratones Endogámicos BALB C , Microesferas , Tamaño de la Partícula
19.
Vaccine ; 27(17): 2372-8, 2009 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-19428853

RESUMEN

Blank polymeric lamellar substrate particles (PLSP) of poly (l-lactide) were prepared and recombinant hepatitis B surface antigen (rHBsAg) was adsorbed onto these particles. The physical characteristics of blank PLSPs or PLSP-rHBsAg in vitro and its immunological responses in Balb/c mice were investigated. The average size of the particles was less than 10microm. Antigen adsorption efficiency was found to be 62.66+/-1.26%. Immunization with PLSP-rHBsAg resulted in upregulation of specific cellular (lymphoproliferation, IFN-gamma and NO release) as well as IgG response in animals. These responses were higher than those produced by two-dose schedule of alum-adsorbed antigen (alum-rHBsAg). Thus in conclusion, in terms of convenience and efficacy PLSP-rHBsAg is superior to alum-rHBsAg.


Asunto(s)
Adyuvantes Inmunológicos/fisiología , Portadores de Fármacos/administración & dosificación , Antígenos de Superficie de la Hepatitis B/inmunología , Vacunas contra Hepatitis B/inmunología , Hepatitis B Crónica/inmunología , Microesferas , Adyuvantes Inmunológicos/administración & dosificación , Animales , Formación de Anticuerpos , Esquema de Medicación , Antígenos de Superficie de la Hepatitis B/administración & dosificación , Vacunas contra Hepatitis B/administración & dosificación , Hepatitis B Crónica/prevención & control , Humanos , Interferón gamma/biosíntesis , Activación de Linfocitos , Linfocitos/inmunología , Linfocitos/metabolismo , Macrófagos Peritoneales/inmunología , Macrófagos Peritoneales/metabolismo , Ratones , Óxido Nítrico/biosíntesis , Polímeros/química , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/inmunología
20.
BMC Nephrol ; 10: 4, 2009 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-19220921

RESUMEN

BACKGROUND: Chronic kidney disease (CKD) is increasingly being recognized as an emerging public health problem in India. However, community based estimates of low glomerular filtration rate (GFR) and proteinuria are few. Validity of traditional serum creatinine based GFR estimating equations in South Asian subjects is also debatable. We intended to estimate and compare the prevalence of low GFR, proteinuria and associated risk factors in North India using Cockcroft-Gault (CG) and Modification of Diet In Renal Disease (MDRD) equation. METHODS: A community based, cross-sectional study involving multistage random cluster sampling was done in Delhi and its surrounding regions. Adults > or = 20 years were surveyed. CG and MDRD equations were used to estimate GFR (eGFR). Low GFR was defined as eGFR < 60 ml/min/1.73 m2. Proteinuria (> or = 1+) was assessed using visually read dipsticks. Odds ratios, crude and adjusted, were calculated to ascertain associations between renal impairment, proteinuria and risk factors. RESULTS: The study population had 3,155 males and 2,097 females. The mean age for low eGFR subjects was 54 years. The unstandardized prevalence of low eGFR was 13.3% by CG equation and 4.2% by MDRD equation. The prevalence estimates of MDRD equation were lower across gender and age groups when compared with CG equation estimates. There was a strong correlation but poor agreement between GFR estimates of two equations. The survey population had a 2.25% prevalence of proteinuria. In a multivariate logistic regression analysis; age above 60 years, female gender, low educational status, increased waist circumference, hypertension and diabetes were associated with low eGFR. Similar factors were also associated with proteinuria. Only 3.3% of subjects with renal impairment were aware of their disease. CONCLUSION: The prevalence of low eGFR in North India is probably higher than previous estimates. There is a significant difference between GFR estimates derived from CG and MDRD equations. These equations may not be useful in epidemiological research. GFR estimating equations validated for South Asian populations are needed before reliable estimates of CKD prevalence can be obtained. Till then, primary prevention and management targeted at CKD risk factors must play a critical role in controlling rising CKD magnitude. Cost-benefit analysis of targeted screening programs is needed.


Asunto(s)
Algoritmos , Enfermedades Renales/epidemiología , Proteinuria/epidemiología , Adulto , Anciano , Consumo de Bebidas Alcohólicas/epidemiología , Antropometría , Comorbilidad , Creatinina/sangre , Estudios Transversales , Países en Desarrollo , Diabetes Mellitus/epidemiología , Tasa de Filtración Glomerular , Humanos , Hipertensión/epidemiología , India/epidemiología , Enfermedades Renales/diagnóstico , Persona de Mediana Edad , Obesidad/epidemiología , Prevalencia , Factores de Riesgo , Muestreo , Fumar/epidemiología , Cambio Social
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