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1.
Plant Physiol Biochem ; 203: 108039, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37717347

RESUMO

Arbuscular mycorrhiza (AM) has been reported to influence secondary metabolism of Ocimum tenuiflorum L., thereby improving its therapeutic and commercial importance. To explain changes in the secondary metabolite profile, the study reports effects of AM on leaf metabolome of two high yielding genotypes of O. tenuiflorum inoculated with Rhizophagus intraradices. NMR-based non-targeted metabolic fingerprinting was related to changes at physiological, biochemical, and molecular levels in mycorrhizal (M) plants. AM resulted in higher accumulation of sucrose, which could be related with enhanced photosynthesis by virtue of increased uptake of mineral nutrients. A strong positive correlation between sucrose and net photosynthetic rate and sucrose and mineral nutrients supported that AM-mediated increase in uptake of mineral nutrients is associated with enhanced photosynthetic rate and accumulation of sucrose. Further, higher sucrose synthase activity resulted in increased glucose. Hexokinase activity was also higher in M plants resulting in higher pyruvate accumulation. On the contrary, Krebs cycle was compromised in M plants as evident by lower activities of its enzymes and concentrations of organic and amino acids. Nevertheless, AM increased activities and expressions of enzymes of terpenoid biosynthesis, shikimate, and phenylpropanoid pathways, thereby resulting in augmented production of terpenoids, phenylalanine, and phenols, respectively. Thus, metabolic reprogramming downstream of glycolysis was apparent wherein AMF resulted in more allocation of carbon resources to secondary metabolism as opposed to primary metabolism, which was supported by Pearson's correlation analysis. Higher C:N ratio in M plants explains the provision of more carbon resources to secondary metabolism as against primary metabolism.

2.
J Gastroenterol Hepatol ; 30(10): 1492-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25867107

RESUMO

BACKGROUND AND AIM: Celiac disease (CeD) is a common autoimmune disorder in which ingestion of gluten and related proteins leads to inflammation in the small intestine. Although the histological findings in CeD are characteristic, they are not specific. In this study, proton nuclear magnetic resonance (NMR) spectroscopy was used to investigate the differences in metabolic profile of duodenal mucosal biopsies of patients with CeD and controls to find out the biomarker/s of villous atrophy. METHODS: Duodenal mucosal biopsies were collected from 29 CeD patients (mean age 26.2 ± 10.8 years) and 17 controls (mean age 34.1 ± 11.1 years) and were subjected to proton NMR spectroscopy following perchloric acid extraction. Assignment of metabolite resonances was carried out and their concentrations were determined. For comparison between the groups unpaired t-test/Wilcoxon rank sum test was used. Partial least squares-discriminant analysis was performed to study the clustering behavior of the samples from CeD patients and controls using the Unscrambler 10.2 software. RESULTS: Partial least squares-discriminant analysis clearly differentiated CeD patients from controls. Significantly higher concentrations of isoleucine, leucine, aspartate, succinate, and pyruvate, and lower concentration of glycerophosphocholine, were observed in the duodenal mucosa of CeD patients compared with controls. The results suggest abnormalities in glycolysis, Krebs cycle (energy deficiency), and amino acid metabolism, which may affect the biosynthetic pathways and consequently contribute to villous atrophy. CONCLUSIONS: NMR spectroscopy with multivariate analysis of duodenal mucosal biopsies revealed a characteristic metabolic profile in CeD patients. The work provided an insight in determining biomarker/s for villous atrophy and diagnosis of CeD patients.


Assuntos
Doença Celíaca/metabolismo , Duodeno/metabolismo , Mucosa Intestinal/metabolismo , Espectroscopia de Ressonância Magnética , Adolescente , Adulto , Aminoácidos/metabolismo , Ácido Aspártico/metabolismo , Atrofia , Biomarcadores/metabolismo , Doença Celíaca/diagnóstico , Ciclo do Ácido Cítrico , Duodeno/patologia , Feminino , Glicólise , Humanos , Mucosa Intestinal/patologia , Isoleucina/metabolismo , Leucina/metabolismo , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prótons , Ácido Pirúvico/metabolismo , Ácido Succínico/metabolismo , Adulto Jovem
3.
Neurochem Int ; 76: 99-108, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25049174

RESUMO

Proper functional development of the auditory cortex (ACx) critically depends on early relevant sensory experiences. Exposure to high intensity noise (industrial/traffic) and music, a current public health concern, may disrupt the proper development of the ACx and associated behavior. The biochemical mechanisms associated with such activity dependent changes during development are poorly understood. Here we report the effects of prenatal chronic (last 10 days of incubation), 110dB sound pressure level (SPL) music and noise exposure on metabolic profile of the auditory cortex analogue/field L (AuL) in domestic chicks. Perchloric acid extracts of AuL of post hatch day 1 chicks from control, music and noise groups were subjected to high resolution (700MHz) (1)H NMR spectroscopy. Multivariate regression analysis of the concentration data of 18 metabolites revealed a significant class separation between control and loud sound exposed groups, indicating a metabolic perturbation. Comparison of absolute concentration of metabolites showed that overstimulation with loud sound, independent of spectral characteristics (music or noise) led to extensive usage of major energy metabolites, e.g., glucose, ß-hydroxybutyrate and ATP. On the other hand, high glutamine levels and sustained levels of neuromodulators and alternate energy sources, e.g., creatine, ascorbate and lactate indicated a systems restorative measure in a condition of neuronal hyperactivity. At the same time, decreased aspartate and taurine levels in the noise group suggested a differential impact of prenatal chronic loud noise over music exposure. Thus prenatal exposure to loud sound especially noise alters the metabolic activity in the AuL which in turn can affect the functional development and later auditory associated behaviour.


Assuntos
Córtex Auditivo/metabolismo , Exposição Materna , Metabolômica , Música , Ruído , Estimulação Acústica , Animais , Embrião de Galinha , Feminino , Gravidez , Espectroscopia de Prótons por Ressonância Magnética
4.
Int J Nanomedicine ; 7: 3503-16, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22848174

RESUMO

The purpose of the study was to develop tumor specific, water dispersible superparamagnetic iron oxide nanoparticles (SPIONs) and evaluate their efficacy as a contrast agent in magnetic resonance imaging (MRI). We have developed SPIONs capped with citric acid/2-bromo-2-methylpropionic acid which are compact, water dispersible, biocompatible having narrow range of size dispersity (8-10 nm), and relatively high T2 relaxivity (R2 = 222L · mmol⁻¹ · sec⁻¹). The targeting efficacy of unconjugated and folic acid-conjugated SPIONs (FA-SPIONS) was evaluated in a folic acid receptor overexpressing and negative tumor cell lines. Folic acid receptor-positive cells incubated with FA-SPIONs showed much higher intracellular iron content without any cytotoxicity. Ultrastructurally, SPIONs were seen as clustered inside the various stages of endocytic pathways without damaging cellular organelles and possible mechanism for their entry is via receptor mediated endocytosis. In vitro MRI studies on tumor cells showed better T2-weighted images in FA-SPIONs. These findings indicate that FA-SPIONs possess high colloidal stability with excellent sensitivity of imaging and can be a useful MRI contrast agent for the detection of cancer.


Assuntos
Meios de Contraste/farmacocinética , Ácido Fólico/farmacocinética , Espectroscopia de Ressonância Magnética/métodos , Nanopartículas de Magnetita/química , Meios de Contraste/química , Estabilidade de Medicamentos , Receptores de Folato com Âncoras de GPI/metabolismo , Ácido Fólico/química , Células Hep G2 , Histocitoquímica , Humanos , Interações Hidrofóbicas e Hidrofílicas , Células MCF-7 , Microscopia Eletrônica de Transmissão , Imagens de Fantasmas
5.
Biomaterials ; 33(10): 2936-51, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22264522

RESUMO

There is much interest in utilizing the intrinsic properties of magnetic nanoparticles (MNPs) for the theranostic approaches in medicine. With an aim to develop a potential therapeutics for glioma treatment, efficacy of aqueous dispersible paclitaxel loaded MNPs (Pac-MNPs) were studied in glioblastoma cell line (U-87). The identified potential receptor, glycoprotein non-metastatic melanoma protein B (GPNMB) overexpressed by glioblastoma cells, was actively targeted using GPNMB conjugated Pac-MNPs in U-87 cells. As blood brain barrier (BBB) is the primary impediment in the treatment of glioblastoma, therefore, an attempt was taken to evaluate the biodistribution and brain uptake of Pac-MNPs in rats. The bioavailability of Pac-MNPs illustrated a prolonged blood circulation in vivo, which demonstrated the presence of significant amounts of drug in rat brain tissues as compared to native paclitaxel. Further, the transmission electron microscopy (TEM) study revealed significant accumulation of the Pac-MNPs in the brain tissues. Being an effective contrast enhancement agent for magnetic resonance imaging (MRI) at tissue levels, the MNPs devoid of any surfactant demonstrated enhanced contrast effect in liver and brain imaging. Hence, the significant prevalence of drugs in the rat brain tissues, in vitro targeting potentiality as well as the augmented contrast effect elicit the non-invasive assessment and theranostic applications of MNPs for brain tumor therapy.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Nanopartículas de Magnetita/química , Paclitaxel/farmacologia , Tensoativos/química , Animais , Transporte Biológico/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/ultraestrutura , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cumarínicos/metabolismo , Endocitose/efeitos dos fármacos , Células HEK293 , Meia-Vida , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita/ultraestrutura , Masculino , Glicoproteínas de Membrana/metabolismo , Microscopia Confocal , Modelos Animais , Paclitaxel/farmacocinética , Tamanho da Partícula , Ratos , Ratos Wistar , Soluções , Distribuição Tecidual/efeitos dos fármacos
6.
ACS Appl Mater Interfaces ; 3(3): 842-56, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21370886

RESUMO

Exercising complementary roles of polymer-coated magnetic nanoparticles for precise drug delivery and image contrast agents has attracted significant attention in biomedical applications. The objective of this study was to prepare and characterize magnetic nanoparticles embedded in polylactide-co-glycolide matrixes (PLGA-MNPs) as a dual drug delivery and imaging system capable of encapsulating both hydrophilic and hydrophobic drugs. PLGA-MNPs were capable of encapsulating both hydrophobic and hydrophilic drugs in a 2:1 ratio. Biocompatibility, cellular uptake, cytotoxicity, membrane potential, and apoptosis were carried out in two different cancer cell lines (MCF-7 and PANC-1). The molecular basis of induction of apoptosis was validated by Western blotting analysis. For targeted delivery of drugs, targeting ligand such as Herceptin was used, and such a conjugated system demonstrated enhanced cellular uptake and an augmented synergistic effect in an in vitro system when compared with native drugs. Magnetic resonance imaging was carried out both in vitro and in vivo to assess the efficacy of PLGA-MNPs as contrast agents. PLGA-MNPs showed a better contrast effect than commercial contrast agents due to higher T(2) relaxivity with a blood circulation half-life ∼ 47 min in the rat model. Thus, our results demonstrated the dual usable purpose of formulated PLGA-MNPs toward either, in therapeutics by delivering different hydrophobic or hydrophilic drugs individually or in combination and imaging for cancer therapeutics in the near future.


Assuntos
Antineoplásicos/administração & dosagem , Portadores de Fármacos/síntese química , Fígado/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita/uso terapêutico , Neoplasias Experimentais/tratamento farmacológico , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Meios de Contraste/síntese química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas de Magnetita/química , Neoplasias Experimentais/patologia , Ratos , Resultado do Tratamento
7.
Neurol India ; 58(3): 377-83, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20644264

RESUMO

BACKGROUND: Cerebral vasospasm is a major cause of morbidity and mortality after subarachnoid hemorrhage (SAH). It usually occurs about 3-9 days after SAH. The pathogenesis involves the release of endogenous spasmogens. Though various treatment modalities are available, none are really effective. AIMS AND OBJECTIVES: The aim of the study was to develop an effective animal model for the study of SAH and vasospasm as well as to study the efficacy of vasodilators, namely nitroglycerine and papaverine, on SAH-induced vasospasm using magnetic resonance angiography. MATERIALS AND METHODS: Fifteen Wistar albino rats, weighing around 150-200 gm were used for the study. Five rats served as controls of SAH-induced vasospasm, while five rats each were used to study the efficacy of intracisternal injection of papaverine or nitroglycerine. RESULTS: Rats demonstrate vasospasm in a manner similar to humans. The maximal vasospasm is seen in the basilar artery. Statistical analysis demonstrates an improvement in vasospasm after instillation of intracisternal papaverine at the end of 2 hours in basilar and left internal cerebral artery. However, nitroglycerine does not produce any significant amelioration of vasospasm. Thus, it can be deduced that the pathogenesis of the vasospasm is more due to the action of cGMPase enzyme rather than inhibition of nitric oxide (NO) synthetase by the spasmogens. The present study is the first study in the English literature to compare the effects of single bolus doses of nitroglycerine and papaverine using magnetic resonance angiography. CONCLUSION: Rats can be used to create an effective model for SAH-induced vasospasm as the pattern resembles human SAH. Papaverine is an effective drug for ameliorating SAH-induced vasospasm. Short-acting NO donors are not as effective in ameliorating vasospasm.


Assuntos
Nitroglicerina/uso terapêutico , Papaverina/uso terapêutico , Hemorragia Subaracnóidea/complicações , Vasodilatadores/uso terapêutico , Vasoespasmo Intracraniano/tratamento farmacológico , Vasoespasmo Intracraniano/etiologia , Análise de Variância , Animais , Modelos Animais de Doenças , Angiografia por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Radiografia , Ratos , Ratos Wistar , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/tratamento farmacológico , Hemorragia Subaracnóidea/patologia
8.
Magn Reson Chem ; 47(6): 478-87, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19280683

RESUMO

A simple, convenient, and direct one-dimensional (1D) (31)P NMR technique is demonstrated for the detection of alkylphosphonic acids (marker of nerve agents). The results of detection were validated after conducting various in-house exercises. The confidence generated by this study was found very useful in detection of different alkylphosphonic acids spiked in various official interlaboratory proficiency tests conducted by Organisation for the Prohibition of Chemical Weapons (OPCW).


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Organofosfonatos/análise , Prótons , Guerra Química , Espectroscopia de Ressonância Magnética/normas , Estrutura Molecular , Isótopos de Fósforo , Padrões de Referência
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