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1.
Med J Armed Forces India ; 78(4): 422-429, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36267515

RESUMEN

Background: Atherosclerotic carotid plaques are one of the most important causes of stroke. Apart from the severity of stenosis, there are certain plaque characteristics such as neovascularization and, surface ulceration which makes a plaque vulnerable. This study was performed to study the plaque characteristics using contrast-enhanced ultrasound (CEUS) and evaluate their association with presence of ischemic cerebrovascular symptoms in these patients. Methods: This study included patients presenting at a tertiary care center, having carotid plaques causing >60% stenosis. CEUS was performed for assessment of intraplaque neovascularity and plaque surface characteristics. These plaque features were then evaluated for their association with presence of ischemic cerebrovascular symptoms in patients. Results: Sixty plaques were studied in 50 patients. Thirty-two plaques were associated with ischemic cerebrovascular symptoms. On CEUS, intraplaque neovascularization was seen in 38 of the 60 plaques studied (63.3%). There was statistically significant association of intraplaque neovascularity and plaque surface characteristics with presence of ischemic cerebrovascular symptoms. Conclusion: CEUS allows better characterization of plaque surface characteristics and also depicts plaque neovascularization, which helps in determining the plaque vulnerability. It should be used as an adjunct to ultrasound and doppler assessment of carotid plaques.

2.
Pharm Res ; 33(7): 1769-81, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27091032

RESUMEN

PURPOSE: In the present investigation, we prepared and evaluated the paclitaxel loaded riboflavin and thiamine conjugated multi walled carbon nanotubes (PTX-Rf-MWCNTs and PTX-Tm-MWCNTs) for targeted delivery to cancer employing MCF-7 cancer cell lines. METHODS: The developed conjugates were characterized using FTIR, NMR spectroscopy, electron microscopy drug loading, release, stability, hemolytic, ex vivo and in vivo studies etc. RESULTS: The percent entrapment efficiency was found to be 87.92 ± 0.48 and 82.75 ± 0.47% of PTX-Tm-MWCNTs, PTX-Rf-MWCNTs, respectively. The percent hemolysis of purified MWCNTs, PTX-MWCNTs, PTX-Tm-MWCNTs and PTX-Rf-MWCNTs was found to be 20.49 ± 0.97, 37.39 ± 0.78, 14.61 ± 0.84 and 11.17 ± 0.77% respectively. The PTX-Tm-MWCNTs and PTX-Rf-MWCNTs showed more cytotoxic effect as compared to PTX and PTX-MWCNTs with PTX-Rf-MWCNTs exhibiting the maximum cytotoxic potential. CONCLUSION: Thus in final outcome, we concluded that the riboflavin and thiamine conjugated MWCNTs shown great promising potential in the treatment of cancer, but more exhaustive data is needed in future.


Asunto(s)
Nanotubos de Carbono/química , Paclitaxel/química , Paclitaxel/farmacología , Riboflavina/química , Riboflavina/farmacología , Tiamina/química , Tiamina/farmacología , Línea Celular Tumoral , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Humanos , Células MCF-7
3.
Med J Armed Forces India ; 72(Suppl 1): S80-S83, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28050078

RESUMEN

Anomalies of the aortic arch associated with diverticulum are rare. We present a case of incidentally detected right-sided aortic arch with Kommerell's diverticulum and aberrant left subclavian artery.

4.
Mol Pharm ; 12(2): 630-43, 2015 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-25517904

RESUMEN

Our main aim in the present investigation was to assess and compare the in vitro and in vivo cancer targeting propensity of doxorubicin (DOX) loaded folic acid (FA) and estrone (ES) anchored PEGylated multiwalled carbon nanotubes (MWCNTs) employing tumor bearing Balb/c mice. The DOX was loaded into the developed functionalized MWCNTs after proper characterization using dialysis diffusion method. The in vitro, ex vivo, and in vivo studies were performed on the MCF-7 cell line for assessment of the cancer targeting propensity. Both qualitative and quantitative cell uptake studies indicated the preferential higher uptake of estrone anchored nanotube formulation compared to other formulations and free DOX owing to the overexpression of estrogen receptors (ERs) on human breast MCF-7 cells. Similarly, the pharmacokinetic and increased antitumor activities also confirmed the elevated cancer targeting propensity of the estrone and folic acid anchored MWCNT formulations. The DOX/ES-PEG-MWCNTs has also shown significantly longer survival span (43 days) than free DOX (18 days) and control group (12 days). Present outcomes from the ex vivo and in vivo studies are deemed to be of great scientific value and shall assist targeted drug delivery formulation scientists for selection of the targeting moieties in the treatment of human breast cancer.


Asunto(s)
Doxorrubicina/farmacocinética , Estrona/química , Ácido Fólico/química , Nanotubos de Carbono/química , Animales , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Neoplasias de la Mama/metabolismo , Supervivencia Celular/fisiología , Doxorrubicina/administración & dosificación , Doxorrubicina/química , Sistemas de Liberación de Medicamentos/métodos , Femenino , Humanos , Células MCF-7 , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Ratones Endogámicos BALB C
5.
Drug Dev Ind Pharm ; 41(8): 1368-75, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25151872

RESUMEN

AIM: Our investigation was aimed to investigate the potential suitability of meloxicam-loaded nanostructured lipid carriers (MLX-NLC) gel for topical application. MAIN METHODS: MLX-NLC gel was prepared and in vivo skin penetration ability of the NLC gel was evaluated using confocal laser scanning microscopy. We studied the effect of MLX-NLC gel on the changes in lipid profile of skin to get an insight into its skin penetration enhancement mechanism. Acetic acid induced writhing test was performed to evaluate the analgesic effect. Drug concentration-time profile of MLX in rat plasma and skin after topical and oral treatment with MLX-NLC gel and oral MLX-solution, respectively, was observed. MLX-NLC gel was subjected to primary skin irritation test, sub-acute dermal toxicity study. Storage stability of MLX-NLC gel was also assessed for 90 days. KEY FINDINGS: NLC gel was effective in permeating Rhodamine 123 to deeper layers of rat skin. Changes in skin lipid prolife were observed in the rat skin on treatment with MLX-NLC gel and the results supported skin lipid extraction as a possible penetration enhancement mechanism. MLX-NLC gel demonstrated sustained pain inhibitory effect. Pharmacokinetics study established that topical application of MLX-NLC gel had the potential to avoid systemic uptake and hence the risk of systemic adverse effects. MLX-NLC gel demonstrated good skin tolerability and biosafety. Excellent physical stability of nanogel was observed at 4 ± 2 °C. SIGNIFICANCE: The study revealed that NLC gel is a promising carrier system for the topical application of MLX without side effects.


Asunto(s)
Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Lípidos/química , Polietilenglicoles/química , Polietileneimina/química , Absorción Cutánea/fisiología , Tiazinas/química , Tiazoles/química , Administración Cutánea , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/metabolismo , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Estabilidad de Medicamentos , Femenino , Lípidos/administración & dosificación , Masculino , Meloxicam , Nanogeles , Polietilenglicoles/administración & dosificación , Polietilenglicoles/metabolismo , Polietileneimina/administración & dosificación , Polietileneimina/metabolismo , Conejos , Ratas , Absorción Cutánea/efectos de los fármacos , Tiazinas/administración & dosificación , Tiazinas/metabolismo , Tiazoles/administración & dosificación , Tiazoles/metabolismo
6.
Drug Dev Ind Pharm ; 41(11): 1888-901, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25738812

RESUMEN

OBJECTIVE: Saquinavir (SQV) is a US-FDA approved HIV protease inhibitor (HPI) for HIV cure. The purpose of the present investigation was to develop and characterize the anticancer potential of the SQV-loaded folic acid (FA) conjugated PEGylated and non-PEGylated poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles (NPs) (SQV-Fol-PEG-PLGA and SQV-Fol-PLGA) employing PC-3 (human prostate) and MCF-7 (human breast) cancer cell lines. MATERIALS AND METHODS: Developed NPs were characterized by IR, NMR, DSC, XRD, size, charge and further tested for drug loading and cellular uptake properties. RESULT: The entrapment efficiency was found to be 56 ± 0.60 and 58 ± 0.80 w/v for SQV-Fol-PEG-PLGA and SQV-PLGA NPs, respectively. The obtained results of SQV-Fol-PEG-PLGA showed enhanced cytotoxicity and cellular uptake and were most preferentially taken up by the cancerous cells via folate receptor-mediated endocytosis (RME) mechanism. At 260 µM concentration, SQV-PLGA NPs and SQV-Fol-PEG-PLGA NPs showed 20%, 20% and 23% cell growth inhibition in PC-3 cells, respectively whereas in MCF-7 cells it was 12%, 15% and 14% cell growth inhibition, respectively. CONCLUSIONS: Developed targeted SQV-Fol-PEG-PLGA NPs were superior anticancer potential as compared to non-targeted SQV-PLGA NPs. Thus, these targeted NPs provide another option for anticancer drug delivery scientists.


Asunto(s)
Antineoplásicos/administración & dosificación , Ácido Fólico/administración & dosificación , Nanopartículas , Saquinavir/administración & dosificación , Antineoplásicos/química , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Línea Celular Tumoral , Portadores de Fármacos/química , Composición de Medicamentos/métodos , Sistemas de Liberación de Medicamentos , Endocitosis/efectos de los fármacos , Femenino , Ácido Fólico/química , Ácido Fólico/farmacología , Humanos , Ácido Láctico/química , Células MCF-7 , Masculino , Tamaño de la Partícula , Poliésteres/química , Polietilenglicoles/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Saquinavir/química , Saquinavir/farmacología
7.
J Food Sci Technol ; 52(7): 4001-14, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26139867

RESUMEN

This paper reports a simple and rapid method for simultaneous determination of the residues of selected herbicides viz. pendimethalin, oxyfluorfen, imazethapyr and quizalofop-p-ethyl in peanut by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A modified approach of the QuEChERS methodology was used to extract the herbicides from the peanut kernel without any clean-up. The method showed excellent linearity (r(2) > 0.99) with no significant matrix effect. Accuracy of the method in terms of average recoveries of all the four herbicides ranged between 69.4 -94.4 % at spiking levels of 0.05, 0.10 and 0.25 mg kg(-1) with intra-day and inter-day precision RSD (%) between 2.6-16.6 and 8.0-11.3, respectively. Limit of quantification (LOQs) was 5.0 µg kg(-1) for pendimethalin, imazethapyr and quizalofop-p-ethyl and 10.0 µg kg(-1) for oxyfluorfen. The expanded uncertainties were <11 % for determination of these herbicides in peanut. The proposed method was successfully applied for analysis of these herbicide residues in peanut samples harvested from the experimental field and the residues were below the detection level.

8.
Cell Mol Biol (Noisy-le-grand) ; 60(3): 10-5, 2014 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-25210855

RESUMEN

Tumor-associated macrophages (TAMs), represent a major subpopulation of tumor infiltrating immune cells. These alternatively activated M2-polarized macrophages are well known for their pro-tumor functions. Owing to their established role in potentiating tumor-neovasculogenesis and metastasis, TAMs have emerged as promising target for anti-cancer immunotherapy. One of the key TAMs related phenomenon that is amenable to therapeutic intervention is their phenotype switching into alternatively activated M2-polarized macrophages. Hindering macrophage polarization towards a pro-tumor M2 phenotype, or better still reprogramming the M2 like TAMs towards M1 subtype is being considered a beneficial anti-cancer strategy. Hypoxic tumor milieu has been proposed as one of the most plausible factor governing M2-polarization of macrophages. We recently demonstrated that hypoxic tumor cells imparted a pro­angiogenic M2 skewed phenotype to macrophages. Furthermore, sizeable body of data indicates for participation of cyclooxygenase-2 (COX-2) in macrophage polarization. Concordantly, inhibition of COX-2 is associated with impaired macrophage polarization. Prompted by this in the current study we decided to explore if inhibition of COX-2 activity via chemical inhibitors may prevent hypoxic cancer cell induced M2-polarization of macrophages. We observed that treatment with Flunixin meglumine, an established preferential inhibitor of COX-2 activity markedly inhibited hypoxic cancer cell induced of M2-polarization of macrophages thereby indicating for usage of COX-2 inhibition as possible anti-cancer treatment modality.


Asunto(s)
Clonixina/análogos & derivados , Inhibidores de la Ciclooxigenasa 2/farmacología , Ciclooxigenasa 2/metabolismo , Macrófagos/citología , Neovascularización Patológica/metabolismo , Animales , Antiinflamatorios no Esteroideos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Hipoxia de la Célula/fisiología , Línea Celular Tumoral , Embrión de Pollo , Membrana Corioalantoides/irrigación sanguínea , Clonixina/farmacología , Femenino , Humanos , Macrófagos/fisiología , Regulación hacia Arriba/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/biosíntesis
9.
J Nanosci Nanotechnol ; 14(7): 5075-87, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24757983

RESUMEN

The present research work describes the formulation of arginine conjugated 3.0G Poly(propylene) imine (PPI) dendrimers, mimicking the surface structure of an endogenous angiogenesis-inhibitor endostatin; for tumor specific delivery of a model anticancer drug, doxorubicin hydrochloride (Dox). Synthesis of PPI dendrimers and conjugation of arginine to surface groups was confirmed by FTIR, NMR, TEM and mass spectrometry. Drug was loaded by equilibrium dialysis method and developed formulation was evaluated for entrapment efficiency, hemolytic toxicity, in vitro drug release, stability, anti-angiogenic activity via in vivo chick embryo chorioallantoic membrane (CAM) assay, and anticancer activity and cell uptake using MCF-7 cancer cell lines. The system exhibited the initial rapid release followed by sustained release of Dox with significant antiangiogenic activity in the CAM assay. Further, the arginine conjugated dendrimers was found to inhibit growth of cancer cells in ex vivo studies with MCF-7 cell lines. Cell uptake studies suggested that in comparison to free drug the formulation was preferably taken up by the tumor cells. Thus the two pronged attack on cancerous tissue i.e., inhibition of angiogenesis and killing of cancer cells by anticancer drug, might prove to be a promising approach in the treatment of fatal disease, cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Dendrímeros/síntesis química , Doxorrubicina/administración & dosificación , Endostatinas/administración & dosificación , Nanocápsulas/administración & dosificación , Nanocápsulas/química , Neoplasias Experimentales/tratamiento farmacológico , Inhibidores de la Angiogénesis/administración & dosificación , Inhibidores de la Angiogénesis/química , Inhibidores de la Angiogénesis/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/química , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Línea Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacocinética , Endostatinas/química , Endostatinas/farmacocinética , Humanos , Células MCF-7 , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Resultado del Tratamiento
10.
J Microencapsul ; 30(7): 709-15, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23534492

RESUMEN

Topical application of enoxaparin (ENX; low molecular weight heparin) prevents the occurrence of thrombosis at traumatic anastomosis site. Particulate carrier system like nanostructured lipid carriers (NLCs) could notably improve skin penetration of ENX. ENX-loaded NLCs were prepared by the solvent diffusion technique. The effect of formulation and process variables on the physicochemical properties of prepared NLCs was studied and characterized. In vitro skin permeation studies revealed better passage of enoxaparin by NLCs than of plain drug. The in vivo skin retention was monitored by fluorescence microscopy. The prepared NLCs when stored for 120 days were found to be more stable at 4 ± 2 °C than room temperature. The overall results of the study demonstrated the importance of carrier composition on the physicochemical properties, morphology, skin irritation and consequently the effectiveness of particulate system as a vehicle for topical delivery of enoxaparin.


Asunto(s)
Anticoagulantes/administración & dosificación , Portadores de Fármacos/química , Enoxaparina/administración & dosificación , Lípidos/química , Nanoestructuras/química , Absorción Cutánea , Administración Cutánea , Animales , Anticoagulantes/farmacocinética , Portadores de Fármacos/metabolismo , Enoxaparina/farmacocinética , Femenino , Metabolismo de los Lípidos , Masculino , Ratas , Piel/metabolismo
11.
Bull Environ Contam Toxicol ; 90(6): 673-8, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23511954

RESUMEN

Deltamethrin (DM) is a broad-spectrum insecticide mainly used to protect crops, fruit and vegetables from pests such as mites, ants, weevils and beetles. Birds, animals and human beings living in same ecosystem are directly or indirectly at the risk of exposure to this insecticide leading to substantial decrease in growth. Thus we studied DM induced toxicity and ameliorative effects of alpha-tocopherol in broiler birds. DM was estimated in liver, breast and leg muscles of chickens feeding with only DM or DM with alpha-tocopherol daily for 42 days. Birds exposed to DM showed a dose dependent decrease in body weight on 5th, 6th and 7th weeks as compared to controls, and alpha-tocopherol partially restored the reduction in body weight. DM residue was found higher in liver as compared to breast and leg muscles.


Asunto(s)
Insecticidas/toxicidad , Nitrilos/toxicidad , Piretrinas/toxicidad , alfa-Tocoferol/farmacología , Animales , Pollos/crecimiento & desarrollo , Insecticidas/aislamiento & purificación , Insecticidas/farmacocinética , Límite de Detección , Nitrilos/aislamiento & purificación , Nitrilos/farmacocinética , Piretrinas/aislamiento & purificación , Piretrinas/farmacocinética , Distribución Tisular
12.
Brain Inform ; 10(1): 18, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37524933

RESUMEN

Human behaviour reflects cognitive abilities. Human cognition is fundamentally linked to the different experiences or characteristics of consciousness/emotions, such as joy, grief, anger, etc., which assists in effective communication with others. Detection and differentiation between thoughts, feelings, and behaviours are paramount in learning to control our emotions and respond more effectively in stressful circumstances. The ability to perceive, analyse, process, interpret, remember, and retrieve information while making judgments to respond correctly is referred to as Cognitive Behavior. After making a significant mark in emotion analysis, deception detection is one of the key areas to connect human behaviour, mainly in the forensic domain. Detection of lies, deception, malicious intent, abnormal behaviour, emotions, stress, etc., have significant roles in advanced stages of behavioral science. Artificial Intelligence and Machine learning (AI/ML) has helped a great deal in pattern recognition, data extraction and analysis, and interpretations. The goal of using AI and ML in behavioral sciences is to infer human behaviour, mainly for mental health or forensic investigations. The presented work provides an extensive review of the research on cognitive behaviour analysis. A parametric study is presented based on different physical characteristics, emotional behaviours, data collection sensing mechanisms, unimodal and multimodal datasets, modelling AI/ML methods, challenges, and future research directions.

13.
J Food Sci Technol ; 48(2): 183-189, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21350589

RESUMEN

Aloe vera (Aloe barbadensis Miller) cubes of 12.5 × 12.5 × 12.5 mm thick were osmosed for 4 h in sugar syrup of 30, 40 and 50°Brix concentration and temperatures of 30 and 50°C at constant syrup to fruit ratio of 5:1. Osmosed and unosmosed aloe vera samples were hot air dried at 50, 60, 70 and 80°C with constant air velocity of 1.5 m/s. The water loss, solid gain and convective drying behaviour were recorded during experiments. It was observed that water loss and solid gain ranged from 39.2 to 71.3 and 2.7 to 6.3%, respectively during osmo-drying. The moisture diffusivity varied from 2.9 to 8.0 × 10(-9) m²/s and 2.7 to 4.6 × 10(-9) m²/s during air drying of osmosed and unosmosed aloe vera samples, respectively. Drying air temperature and osmosis as pre-treatment affected the water loss, solid gain, diffusivity at -p ≤ 0.01.

14.
Cell Mol Biol (Noisy-le-grand) ; 56 Suppl: OL1239-51, 2010 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-20158977

RESUMEN

We studied anti-inflammatory effect of ethanolic extract of Solanum nigrum leaves and Ricinus communis root bark using chicken skin as model. Leaves of these plants were dried under shade and powdered. 5% Ethanol extracts were prepared using Soxhlet and injected intraperitoneally (400 mg/kg) 1 hour prior to the induction of inflammation. Inflammatory lesion were induced by intradermal injection of 0.02 ml 0.05%w/v histamine (0-2 min, 15 min, 30 min, 1 hr and 6 hr) and 1% w/v carrageenan (0-2 min, 30 min, 1 hr, 6 hr, 12 hr and 48 hr) in different group of birds. Increase in vascular permeability was studied using Evans blue as a permeability marker both qualitatively and quantitatively. Cellular events were studied in skin lesions at various time intervals and cells were counted at high power objective under microscope. Both, extracts exhibited significant decrease in permeability response at an early stage (0-2 min) of histamine as well as in carrageenan induced inflammatory lesions. There was a significant (p< 0.05) suppression in the emigration of heterophils, monocytoid cells, basophils and total leukocytosis in Solanum nigrum and Ricinus communis pretreated chicken skin lesions as compared to the control. The present study suggested antihistamine and anti-inflammatory properties of ethanolic extract of Solanum nigrum and Ricinus communis.


Asunto(s)
Antiinflamatorios/farmacología , Extractos Vegetales/farmacología , Ricinus/química , Piel/efectos de los fármacos , Solanum nigrum/química , Animales , Permeabilidad Capilar/efectos de los fármacos , Carragenina/toxicidad , Pollos , Histamina/toxicidad , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inyecciones Intraperitoneales , Leucocitos/efectos de los fármacos , Leucocitos/inmunología , Hojas de la Planta/química , Raíces de Plantas/química , Piel/patología , Factores de Tiempo
15.
Int J Cosmet Sci ; 32(2): 89-98, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20412216

RESUMEN

Many molecular sunscreens penetrate into the skin causing photo-allergic and photo-toxic reactions as well as skin irritations establishing an urgent need for the development of a safer sunscreen formulation. The search for active substances, efficient combinations, and the design of novel vehicles or carriers has led to the implementation of new cosmetic systems in contrast to the classic forms such as creams or gels. Amongst various approaches utilized to improve performance of sunscreening agents, the use of multiparticulate delivery systems is gaining increasing attention amongst researchers. Multiparticulate delivery systems can be incorporated into gels, creams, liquids, powders or other formulations, and can release active agents depending on their temperature, moisture, friction, volatility of the entrapped ingredients or time. These systems also have the ability of scattering or reflecting incoming UV radiations and therefore can act as physical sunscreens on their own.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Protectores Solares/química , Humanos , Microesferas , Protectores Solares/administración & dosificación
16.
Pharmazie ; 65(12): 891-5, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21284258

RESUMEN

The unique characteristics of dendrimers make them attractive candidates as drug carriers. However, the toxicity associated with dendrimers is a basic hurdle in their biomedical application. To ensure development of dendrimer based safe and effective delivery systems, the effect of dendrimers on human erythrocytes (RBCs) must be studied. The present study explores the toxicological behavior of different generations of poly(propylene imine) dendrimers on human RBCs. Plain fifth generation PPI dendrimers (1 mg/mL) showed approximately 6.39% hemolysis which was an indication of their suitability in drug delivery. The study was conducted on all generations from 0.5 to 5.0 G of PPI dendrimers.


Asunto(s)
Dendrímeros/química , Dendrímeros/farmacología , Eritrocitos/efectos de los fármacos , Polipropilenos/química , Polipropilenos/farmacología , Química Farmacéutica , Sistemas de Liberación de Medicamentos , Deformación Eritrocítica/efectos de los fármacos , Membrana Eritrocítica/efectos de los fármacos , Excipientes , Hemoglobinas/análisis , Hemólisis/efectos de los fármacos , Humanos , Técnicas In Vitro , Espectroscopía de Resonancia Magnética , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Propiedades de Superficie
17.
Pharmazie ; 65(3): 155-61, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20383933

RESUMEN

Bioequivalence is a vital concern in drug development even more significant in the case of Narrow Therapeutic Index (NTI) drugs. In clinical development of New Chemical Entities (NCE), bioequivalence studies necessitate to be performed when the formulation of the pharmaceutical dosage form has been changed. In vivo pharmacokinetic data can be used as surrogate parameters for in vivo solubility and permeability data. The Biopharmaceutics Classification System (BCS) has emerged as a helpful tool in product development by alluding to the in vivo performance of the active substance. The bio-relevance of the BCS properties and the in vitro release are best expressed through a correlation between in vitro and in vivo data. Recently BCS has been implemented for waiving bioequivalence studies on the basis of the solubility and gastrointestinal permeability of drug substance and can be strategically deployed to save time and resources during generic drug development. The BCS has been adopted as a very useful tool for in vivo drug design and development worldwide, particularly in terms of regulatory standards. A BCS-based biowaiver has become an important and cost-saving tool in approval of generic drugs.


Asunto(s)
Preparaciones Farmacéuticas/clasificación , Farmacocinética , Equivalencia Terapéutica , Animales , Química Farmacéutica , Evaluación Preclínica de Medicamentos , Humanos , Absorción Intestinal , Boca/metabolismo , Permeabilidad , Preparaciones Farmacéuticas/administración & dosificación , Preparaciones Farmacéuticas/química , Preparaciones Farmacéuticas/metabolismo , Solubilidad
18.
Eur J Pharm Sci ; 33(4-5): 424-33, 2008 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-18359615

RESUMEN

We have evaluated the efficiency of novel modified liposomes (ethosomes) for transcutaneous immunization (TCI) against Hepatitis B. Antigen-loaded ethosomes were prepared and characterized for shape, lamellarity, fluidity, size distribution, and entrapment efficiency. Spectral bio-imaging and flow cytometric studies showed efficient uptake of Hepatitis B surface antigen (HBsAg)-loaded ethosomes by murine dendritic cells (DCs) in vitro, reaching a peak by 180 min. Transcutaneous delivery potential of the antigen-loaded system using human cadaver skin demonstrated a much higher skin permeation of the antigen in comparison to conventional liposomes and soluble antigen preparation. Topically applied HBsAg-loaded ethosomes in experimental mice showed a robust systemic and mucosal humoral immune response compared to intramuscularly administered alum-adsorbed HBsAg suspension, topically applied plain HBsAg solution and hydroethanolic (25%) HBsAg solution. The ability of the antigen-pulsed DCs to stimulate autologous peripheral blood lymphocytes was demonstrated by BrdU assay and a predominantly TH1 type of immune response was observed by multiplex cytometric bead array analysis. HBsAg-loaded ethosomes are able to generate a protective immune response and their ability to traverse and target the immunological milieu of the skin may find a potential application in the development of a transcutaneous vaccine against Hepatitis B virus (HBV).


Asunto(s)
Antígenos de Superficie de la Hepatitis B/administración & dosificación , Vacunas contra Hepatitis B/administración & dosificación , Inmunización/métodos , Membrana Mucosa , Administración Cutánea , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Citocinas/inmunología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Estabilidad de Medicamentos , Fibroblastos/efectos de los fármacos , Fibroblastos/inmunología , Citometría de Flujo , Vacunas contra Hepatitis B/farmacocinética , Humanos , Inmunoglobulina A/inmunología , Inmunoglobulina G/inmunología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Liposomas , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Membrana Mucosa/efectos de los fármacos , Membrana Mucosa/inmunología , Piel/efectos de los fármacos , Piel/inmunología , Piel/metabolismo , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología
19.
Curr Drug Deliv ; 5(4): 275-81, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18855596

RESUMEN

The present study was aimed at in vitro and in vivo evaluation of PEGylated elastic liposomal formulation for lymphatic targeting of zidovudine (AZT). PEGylated elastic liposomal formulation was prepared and characterized for characteristic in vitro, ex-vivo and in vivo parameters. The plain and PEGylated elastic liposomal formulation showed transdermal flux of 99.8+/-5.8 and 119.5+/-5.2 microg/cm(2)/hr, respectively across the rat skin. Results of biodistribution study indicated 27-fold higher accumulation of AZT in lymphoid tissues after application of PEGylated elastic liposomes as compared to free drug. The efficient localization of elastic liposomal formulation in lymphatic system is of particular interest for HIV therapy, taking in account that replication of HIV mainly takes place in the lymphoid system. The Cellular uptake studies showed significantly higher cellular uptake in lymphoid cells (MT-2 cell line) from PEGylated elastic liposomal formulation (88.9+/-8.7%) in comparison to phosphate buffer saline (PBS, pH 7.4) solution of drug (27.1+/-2.8%). The entrapment of AZT into PEGylated elastic liposomes represents a potential approach for overcoming the toxicity by its selective uptake in lymphoid organs. This represents attractive approach for sustained and targeted delivery of AZT.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Tejido Linfoide/metabolismo , Zidovudina/administración & dosificación , Animales , Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacocinética , Línea Celular , Química Farmacéutica , Estabilidad de Medicamentos , Liposomas , Polietilenglicoles/administración & dosificación , Ratas , Ratas Sprague-Dawley , Absorción Cutánea , Zidovudina/química , Zidovudina/farmacocinética
20.
Curr Drug Deliv ; 5(3): 199-206, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18673263

RESUMEN

In order to get across the intact skin, drug-laden carriers have to pass through narrow, confining pores of 50 nm or less diameter, under the influence of a suitable transdermal gradient. Novel ultradeformable carriers, the elastic liposomes achieve this target via its deforming and self-optimizing property. The main goal of this work was to prepare and characterize, elastic liposomes bearing melatonin, an anti-jet lag agent for its efficient transdermal delivery. Elastic liposomes bearing melatonin were prepared by modified extrusion method and characterized for shape, lamellarity, size distribution, percent drug loading, turbidity profile by Transmission electron microscopy (TEM), Dynamic light scattering (DLS), Mini-column centrifugation and Nephelometric techniques. The effect of different formulation variables like type of surfactant and concentration of surfactant on the deformability of vesicles, turbidity changes, transdermal flux across human cadaver skin, amount of drug deposited into the skin were investigated. Confocal laser scanning (CLS) micrographs revealed that probe (Rhodamine Red) loaded elastic liposomes were able to penetrate much deeper than the probe loaded conventional rigid liposomes. Out of the three surfactants utilized namely, Span 80, Sodium cholate and Sodium dodecylsulphate, formulation bearing Span 80 at an optimum lipid: surfactant ratio of 85:15% w/w proved to be the best in all parameters studied. The optimum skin permeation profile including greater transdermal flux and lower lag time of melatonin from optimized elastic liposomes via human cadaver skin was observed. Our results of the present study demonstrated the feasibility of elastic liposomal system for transdermal delivery of this anti- jet lag agent, which provides better transdermal flux, higher entrapment efficiency, greater skin drug deposition and possesses the ability of a self-penetration enhancer as compared to conventional liposomes.


Asunto(s)
Administración Cutánea , Síndrome Jet Lag/tratamiento farmacológico , Liposomas , Melatonina/uso terapéutico , Absorción Cutánea/fisiología , Química Farmacéutica , Cromatografía Líquida de Alta Presión , Composición de Medicamentos , Elasticidad , Excipientes , Humanos , Técnicas In Vitro , Melatonina/administración & dosificación , Microscopía Confocal , Microscopía Electrónica de Transmisión , Piel/ultraestructura , Espectroscopía Infrarroja por Transformada de Fourier
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