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1.
J Environ Sci Health B ; 54(5): 394-406, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30755093

RESUMEN

Extraction and quantification of pesticide residue from the milk matrix at or below the established maximum residue limit (MRL) is a challenging task for both analytical chemists and the regulatory institutions to take corrective actions for the human health and safety. The main aim of the study is to develop a simple rapid and less expensive QuEChERS extraction and cleanup method for simultaneous analysis of 41 multiclass pesticide residue in milk by gas chromatography-electron capture detector (GC-ECD), followed by confirmation of the residues with gas chromatography-mass spectrometer (GC-MS). Effect of sorbent type, temperature, spiking concentration, matrix effect (ME), measurement uncertainty (MU), inter- and intra-assay repeatability, reproducibility of recovery, and trueness of the results were investigated to validate the effectiveness of the method. Limit of determination (LOD) and limit of quantitation (LOQ) for all the analytes ranged within 0.001-0.02 and 0.002-0.05 µg mL-1, respectively. The % recovery of all the pesticides ranged between 91.38 and 117.56% with relative standard deviation (RSD) below 2.79%. The MU for all the analytes was ≤29% of respective LOQs, and except for few pesticides, the ME was largely negative. The method fulfilled all the SANTE guidelines and thus can be extended for routine analysis of multiclass pesticide residue in milk.


Asunto(s)
Contaminación de Alimentos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Leche/química , Residuos de Plaguicidas/análisis , Animales , Cromatografía de Gases/métodos , Análisis de los Alimentos/métodos , Límite de Detección , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Temperatura
2.
Curr Pharm Des ; 28(2): 116-132, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34809540

RESUMEN

The blood-brain barrier (BBB) prevents the transfer of many therapeutic drugs across the brain. Therefore, the leading treatment strategies of Alzheimer's disease (AD) are often unsuccessful. Another challenge is to achieve specific targetability across BBB and diagnosis. Herein, theranostic-based strategies are emerging in order to combine therapeutic, targeting, and diagnostic capabilities. Recent nanotechnological advancements enable a common platform for the formulation and development of efficient theranostics. This can be attained by engineering some of the properties of nanomaterials, thus enabling them to become efficient and suitable theranostics. In this review, we discuss the various novel approaches of theranostic nanomaterials owing to multimodal functionality across the brain as an effective and probable treatment as well as early (timely) diagnosis of Alzheimer's disease. In this respect, we conducted a PubMed search to review the latest development in theranostic nanomaterials, especially for Alzheimer's (major type of dementia) therapy that led us to discuss the present theranostic nanomaterials utilizing drug carriers that include cargo, targeting ligands, and imaging agents for delivery to particular tissues, cells, or subcellular components. Our focus is on strategies for syntheses, but we will also consider the challenges and prospects associated with this evolving technology. The current review includes knowledge of the history, overview of AD, and therapeutics with a future approach of using theranostic nanomaterials as personalized medicines.


Asunto(s)
Enfermedad de Alzheimer , Nanopartículas , Nanoestructuras , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/tratamiento farmacológico , Portadores de Fármacos , Humanos , Nanopartículas/uso terapéutico , Nanoestructuras/uso terapéutico , Medicina de Precisión , Nanomedicina Teranóstica/métodos
3.
Bioorg Med Chem Lett ; 21(11): 3475-8, 2011 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-21515043

RESUMEN

A series of chalcone based PPAR-α agonists were synthesized and evaluated for their antidyslipidemic activity in high fructose high fat fed dyslipidemic Syrian golden hamsters. Most of the compounds exhibited antidyslipidemic activity. The compounds 4c and 4f have been identified as most potent antidyslipidemics. A definite structure-activity relationship was observed while varying the nature as well as the position of the substituent.


Asunto(s)
Ácidos Fíbricos/síntesis química , Ácidos Fíbricos/farmacología , Hipolipemiantes/síntesis química , Hipolipemiantes/farmacología , Animales , Chalcona/síntesis química , Chalcona/química , Chalcona/farmacología , Cricetinae , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Dislipidemias/tratamiento farmacológico , Ácidos Fíbricos/química , Humanos , Hipolipemiantes/química , Metabolismo de los Lípidos/efectos de los fármacos , Estructura Molecular , Relación Estructura-Actividad
4.
RSC Adv ; 9(51): 29856-29863, 2019 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-35531502

RESUMEN

A new fluorescent sensor 5 based on a fused imidazopyridine scaffold has been designed and synthesized via cascade cyclization. The reaction features the formation of three different C-N bonds in sequence. Imidazopyridine based fluorescent probe 5 exhibits highly sensitive and selective fluorescent sensing for Fe3+('turn-on') and Hg2+('turn-off'). The excellent selectivity of imidazopyridine for Fe3+/Hg2+ was not hampered in the presence of any of the competing cations. The limit of detection (LOD) of 5 toward Fe3+ and Hg2+ has been estimated to be 4.0 ppb and 1.0 ppb, respectively, with a good linear relationship (R 2 = 0.99). Notably, 5 selectively detects Fe3+/Hg2+ through fluorescence enhancement signalling both in vitro and in HeLa cells.

5.
Artículo en Inglés | MEDLINE | ID: mdl-29723115

RESUMEN

Syntheses of novel 3'-azido-3'-deoxy-2'-O,4'-C-methylene-α-L-ribofuranosyl nucleosides have been carried out from 3'-azido-3'-deoxy-4'-C-hydroxymethyl-ß-D-xylofuranosyl nucleosides following both chemical and chemo-enzymatic methodologies. The precursor nucleoside in turn was synthesized from a common glycosyl donor 4-C-acetoxymethyl-1,2,5-tri-O-acetyl-3-azido-3-deoxy-α,ß-D-xylofuranose, which was obtained by the acetolysis of 4-C-acetoxymethyl-5-O-acetyl-3-azido-3-deoxy-1,2-O-isopropylidene-α-D-xylofuranose in 96% yield. It has been observed that a chemo-enzymatic pathway for the synthesis of targeted nucleosides is much more efficient than a chemical pathway, leading to the improvement in yield for the synthesis of 3'-azido-3'-deoxy-α-L-ribofuranosyl thymine and uracil from 49 to 89% and 55 to 93%, respectively.


Asunto(s)
Azidas/síntesis química , Enzimas/química , Nucleósidos/síntesis química , Catálisis , Espectroscopía de Resonancia Magnética , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray , Estereoisomerismo , Relación Estructura-Actividad , Timina/análogos & derivados , Timina/síntesis química , Uracilo/análogos & derivados , Uracilo/síntesis química
6.
Artículo en Inglés | MEDLINE | ID: mdl-29279005

RESUMEN

Multi-location supervised field trials were conducted in India at four locations of the All India Network Project (AINP) on Pesticide Residues to study the persistence, dissipation and risk assessment of flubendiamide and deltamethrin on cucumber (Cucumis sativus). Residues of flubendiamide and deltamethrin on cucumber resulting from three spray applications of a combination formulation (flubendiamide 90% + deltamethrin 60%, 150 SC) at recommended (22.5 + 15 g a.i./ha) and double the recommended (45 + 30 g a.i./ha) dose were analysed. On the basis of persistence and dissipation studies, the half- life (T1/2) of flubendiamide on cucumber varied from 1.40 to 2.98 (recommended dose) and 1.55 to 2.76 days (double the recommended dose), while that of deltamethrin ranged from 2.5 to 4.9 (recommended dose) and 2.7 to 3.9 days (double the recommended dose) at the four locations. On the basis of supervised field trial data and using OECD calculator, MRLs in the combination product of 3 mg kg-1 for flubendiamide and 1.5 mg kg-1 for deltamethrin has been proposed for consideration by the Food Safety and Standards Authority of India (FSSAI). Codex, EU and EPA have fixed MRL of 0.2 mg kg-1 for flubendiamide and deltamethrin.


Asunto(s)
Benzamidas/análisis , Cucumis sativus/química , Contaminación de Alimentos/análisis , Nitrilos/análisis , Residuos de Plaguicidas/análisis , Piretrinas/análisis , Sulfonas/análisis , Agricultura , Cromatografía Líquida de Alta Presión , Análisis de los Alimentos , Humanos , India , Espectrometría de Masas , Estructura Molecular , Medición de Riesgo
7.
J Environ Biol ; 27(2 Suppl): 419-21, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-17436536

RESUMEN

Experiments on air and biomonitoring were conducted to evaluate pollution impact on the vegetation along the road in Jalgaon City, Maharashtra. The plantation along the roads and mainly includes neem (Aadirachta indica), peepal (Ficus religiosa), banyan (Ficus benghalensis), almond (Terminalia catapa). For biomonitoring, leaf area, total chlorophyll, plant protein were analyzed to study the impact of air pollutants. It was observed that vegetation at roadside with heavy traffic and markets was much affected by vehicular emission. Significant decrease in total chlorophyll and protein content was observed with reduced leaf area. It is concluded that plants can be used as indicators for urban air pollution, and there is need to protect the roadside plants from air pollution.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Monitoreo del Ambiente/métodos , Plantas/efectos de los fármacos , India
8.
Colloids Surf B Biointerfaces ; 136: 150-9, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26381698

RESUMEN

The present investigation reports the modification of chitosan nanoparticles with a ligand 4-sulfated N-acetyl galactosamine (4-SO4GalNAc) for efficient chemotherapy in leishmaniasis (SCNPs) by using dual strategy of targeting. These (SCNPs) were loaded with amphotericin B (AmB) for specific delivery to infected macrophages. Developed AmB loaded SCNPs (AmB-SCNPs) had mean particle size of 333 ± 7 nm, and showed negative zeta potential (-13.9 ± 0.016 mV). Flow cytometric analysis revealed enhanced uptake of AmB-SCNPs in J774A.1, when compared to AmB loaded unmodified chitosan NPs (AmB-CNPs). AmB-SCNPs provide significantly higher localization of AmB in liver and spleen as compared to AmB-CNPs after i.v. administration. The study stipulates that 4-SO4GalNAc assures of targeting, resident macrophages. Highly significant anti-leishmanial activity (P<0.05 compared with AmB-CNPs) was observed with AmB-SCNPs, causing 75.30 ± 3.76% inhibition of splenic parasitic burdens. AmB-CNPs and plain AmB caused only 63.89 ± 3.44% and 47.56 ± 2.37% parasite inhibition, respectively, in Leishmania-infected hamsters (P<0.01 for AmB-SCNPs versus plain AmB and AmB-CNPs versus plain AmB).


Asunto(s)
Acetilgalactosamina/química , Anfotericina B/administración & dosificación , Quitosano/química , Leishmaniasis/tratamiento farmacológico , Nanopartículas , Sulfatos/química , Animales , Línea Celular , Cromatografía Líquida de Alta Presión , Macrófagos/parasitología , Ratones , Microscopía Electrónica de Transmisión , Espectroscopía Infrarroja por Transformada de Fourier
9.
PLoS One ; 9(7): e101201, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24999979

RESUMEN

Because of a large number of molecular similarities with higher eukaryotes, the fission yeast Schizosaccharomyces pombe has been considered a potentially ideal host for expressing human proteins having therapeutic and pharmaceutical applications. However, efforts in this direction are hampered by lack of a strong promoter. Here, we report the isolation and characterization of a strong, constitutive promoter from S. pombe. A new expression vector was constructed by cloning the putative promoter region of the lsd90 gene (earlier reported to be strongly induced by heat stress) into a previously reported high copy number vector pJH5, which contained an ARS element corresponding to the mat2P flanking region and a truncated URA3m selectable marker. The resulting vector was used to study and compare the level of expression of the luciferase reporter with that achieved with the known vectors containing regulatable promoter nmt1 and the strong constitutive promoter adh1 in S. pombe and the methanol-inducible AOX1 promoter in Pichia pastoris. Following growth in standard media the new vector containing the putative lsd90 promoter provided constitutive expression of luciferase, at a level, which was 19-, 39- and 10-fold higher than that achieved with nmt1, adh1 and AOX1 promoters, respectively. These results indicate a great potential of the new lsd90 promoter-based vector for commercial scale expression of therapeutic proteins in S. pombe.


Asunto(s)
Genes Reporteros/genética , Ingeniería Genética/métodos , Luciferasas/genética , Regiones Promotoras Genéticas/genética , Proteínas de Schizosaccharomyces pombe/genética , Schizosaccharomyces/genética , Clonación Molecular , Expresión Génica , Vectores Genéticos/genética , Cinética , Pichia/genética
10.
Toxicol Int ; 18(1): 9-13, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21430913

RESUMEN

Protective effect of Ocimum sanctum was evaluated on chlorpyrifos-induced genotoxicity in in vivo and in vitro models. Two different concentrations of pesticide were taken, i.e., 1/5 and 1/15 of LD(50) of chlorpyrifos for the in vivo study. Rats were pre-treated orally with O. sanctum extract (OE) at 50 mg/kg b.wt. For the in vitro studies, human lymphocyte cultures were exposed to 75 µg/ml chlorpyrifos with and without OE. Structural and numerical (both aneuploidy and euploidy types) chromosomal aberrations (CAs) were scored for the assessment of induced genotoxic effects, while the variation in mitotic index (MI) was considered as a monitor for induced cellular toxicity. The same concentration of the pesticide (75 µg/ml) was taken to study the DNA damage by comet assay. Results showed that lymphocytes treated with the pesticide exhibited increased DNA damage but the increase was statistically insignificant (P>0.05). In rats pretreated with OE, a significant (P<0.01) increase in MI was observed and there was a significant decrease in the frequency of aberrant cells as compared to the rats treated with chlorpyrifos alone. A significant (P<0.05) increase in CA was observed in cultures treated with 75 µg/ml chlorpyrifos as compared to controls, which decreased significantly (P<0.05) with OE pretreatment.

11.
Indian J Occup Environ Med ; 15(3): 139-41, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22412294

RESUMEN

The present investigation was undertaken to study the role of working conditions in occupational hazards among bidi rollers occupationally exposed to tobacco dust with reference to DNA damage in peripheral blood lymphocytes. Initially, biomonitoring was conducted by estimating urinary thioether to detect the extent of xenobiotic exposure, and genotoxicity was evaluated by assessing DNA damage and micronucleus frequency in buccal epithelial cells in female bidi rollers occupationally exposed to bidi tobacco dust. Student's t-test was used to test the significance between the means. Results showed a significant increase in urinary thioether level in during-shift urine samples as compared to pre-shift samples, which indicated exposure of bidi rollers to xenobiotic compounds. A significant increase in DNA damage was observed in the rollers working in confined environment as compared to those who worked in open and mixed kind of working conditions. Keeping in view the adverse effects of tobacco inhalation on the genotoxic effects in bidi rollers as an occupational hazard and in order to minimize the hazardous effects, it is recommended that masks should be worn by the bidi rollers during work to minimize inhalation of tobacco dust. Gloves should be worn particularly if there are bruises etc. in the palm. To minimize the absorption through eyes, covered glasses should be worn. The entire process of bidi rolling may be done preferably under well ventilated conditions. Due care to be taken to sit in the direction facing the direction of wind to avoid inhalation of blown away tobacco dust.

12.
Bioorg Med Chem Lett ; 17(3): 799-802, 2007 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-17095211

RESUMEN

A series of chalcone based aryloxypropanolamines were synthesized and evaluated for their antihyperglycemic activity in SLM and STZ rat models. Most of the compounds exhibited moderate to good activity ranging from 6.5% to 31.1% in SLM and 8.3% to 22.6% in STZ models, respectively. The most potent compound 5 g exhibited glucose lowering of 26.7% in SLM and 22.6% in STZ models. A definite structure-activity relationship was observed while varying the nature as well as the position of the amine in ring B.


Asunto(s)
Chalonas/química , Chalonas/farmacología , Hipoglucemiantes/síntesis química , Hipoglucemiantes/farmacología , Animales , Diabetes Mellitus Experimental/tratamiento farmacológico , Hiperglucemia/inducido químicamente , Hiperglucemia/tratamiento farmacológico , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Masculino , Ratas , Ratas Sprague-Dawley , Receptores Adrenérgicos beta 3/efectos de los fármacos , Sacarosa/farmacología
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