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1.
Metab Brain Dis ; 33(2): 467-480, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29101602

RESUMO

There is abundant evidence for both disorganized redox balance and cognitive deficits in major depressive disorder (MDD). Garcinia mangostana Linn (GM) has anti-oxidant activity. We studied the antidepressant-like and pro-cognitive effects of raw GM rind in Flinders Sensitive Line (FSL) rats, a genetic model of depression, following acute and chronic treatment compared to a reference antidepressant, imipramine (IMI). The chemical composition of the GM extract was analysed for levels of α- and γ-mangostin. The acute dose-dependent effects of GM (50, 150 and 200 mg/kg po), IMI (20 mg/kg po) and vehicle were determined in the forced swim test (FST) in FSL rats, versus Flinders Resistant Line (FRL) control rats. Locomotor testing was conducted using the open field test (OFT). Using the most effective dose above coupled with behavioral testing in the FST and cognitive assessment in the novel object recognition test (nORT), a fixed dose 14-day treatment study of GM was performed and compared to IMI- (20 mg/kg/day) and vehicle-treated animals. Chronic treated animals were also assessed with respect to frontal cortex and hippocampal monoamine levels and accumulation of malondialdehyde. FSL rats showed significant cognitive deficits and depressive-like behavior, with disordered cortico-hippocampal 5-hydroxyindole acetic acid (5-HIAA) and noradrenaline (NA), as well as elevated hippocampal lipid peroxidation. Acute and chronic IMI treatment evoked pronounced antidepressant-like effects. Raw GM extract contained 117 mg/g and 11 mg/g α- and γ-mangostin, respectively, with acute GM demonstrating antidepressant-like effects at 50 mg/kg/day. Chronic GM (50 mg/kg/d) displayed significant antidepressant- and pro-cognitive effects, while demonstrating parity with IMI. Both behavioral and monoamine assessments suggest a more prominent serotonergic action for GM as opposed to a noradrenergic action for IMI, while both IMI and GM reversed hippocampal lipid peroxidation in FSL animals. Concluding, FSL rats present with cognitive deficits and depressive-like behaviors that are reversed by acute and chronic GM treatment, similar to that of IMI.


Assuntos
Comportamento Animal/efeitos dos fármacos , Depressão/tratamento farmacológico , Garcinia mangostana/efeitos dos fármacos , Imipramina/farmacologia , Animais , Antidepressivos/farmacologia , Cognição/efeitos dos fármacos , Modelos Animais de Doenças , Masculino , Atividade Motora/efeitos dos fármacos , Ratos
2.
Hum Mutat ; 38(1): 78-85, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27650164

RESUMO

The aryl hydrocarbon receptor interacting protein (AIP) founder mutation R304* (or p.R304* ; NM_003977.3:c.910C>T, p.Arg304Ter) identified in Northern Ireland (NI) predisposes to acromegaly/gigantism; its population health impact remains unexplored. We measured R304* carrier frequency in 936 Mid Ulster, 1,000 Greater Belfast (both in NI) and 2,094 Republic of Ireland (ROI) volunteers and in 116 NI or ROI acromegaly/gigantism patients. Carrier frequencies were 0.0064 in Mid Ulster (95%CI = 0.0027-0.013; P = 0.0005 vs. ROI), 0.001 in Greater Belfast (0.00011-0.0047) and zero in ROI (0-0.0014). R304* prevalence was elevated in acromegaly/gigantism patients in NI (11/87, 12.6%, P < 0.05), but not in ROI (2/29, 6.8%) versus non-Irish patients (0-2.41%). Haploblock conservation supported a common ancestor for all the 18 identified Irish pedigrees (81 carriers, 30 affected). Time to most recent common ancestor (tMRCA) was 2550 (1,275-5,000) years. tMRCA-based simulations predicted 432 (90-5,175) current carriers, including 86 affected (18-1,035) for 20% penetrance. In conclusion, R304* is frequent in Mid Ulster, resulting in numerous acromegaly/gigantism cases. tMRCA is consistent with historical/folklore accounts of Irish giants. Forward simulations predict many undetected carriers; geographically targeted population screening improves asymptomatic carrier identification, complementing clinical testing of patients/relatives. We generated disease awareness locally, necessary for early diagnosis and improved outcomes of AIP-related disease.


Assuntos
Acromegalia/epidemiologia , Acromegalia/genética , Predisposição Genética para Doença , Gigantismo/epidemiologia , Gigantismo/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Acromegalia/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Substituição de Aminoácidos , Mapeamento Cromossômico , Estudos Transversais , Feminino , Frequência do Gene , Genótipo , Gigantismo/diagnóstico , Heterozigoto , Humanos , Irlanda/epidemiologia , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Fenótipo , Risco , Adulto Jovem
3.
J Sep Sci ; 38(12): 2024-32, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25845561

RESUMO

Widely known for its recreational use, the cannabis plant also has the potential to act as an antibacterial agent in the medicinal field. The analysis of cannabis plants/products in both pharmacological and forensic studies often requires the separation of compounds of interest and/or accurate identification of the whole cannabinoid profile. In order to provide a complete separation and detection of cannabinoids, a new two-dimensional liquid chromatography method has been developed using acidic potassium permanganate chemiluminescence detection, which has been shown to be selective for cannabinoids. This was carried out using a Luna 100 Å CN column and a Poroshell 120 EC-C18 column in the first and second dimensions, respectively. The method has utilized a large amount of the available separation space with a spreading angle of 48.4° and a correlation of 0.66 allowing the determination of more than 120 constituents and mass spectral identification of ten cannabinoids in a single analytical run. The method has the potential to improve research involved in the characterization of sensitive, complex matrices.


Assuntos
Canabinoides/química , Cannabis/química , Luminescência , Permanganato de Potássio/química , Canabinoides/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Espectrometria de Massas , Folhas de Planta/química , Raízes de Plantas/química , Solventes/química
4.
Anal Bioanal Chem ; 406(23): 5669-76, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24317518

RESUMO

High-performance liquid chromatography with chemiluminescence detection based on the reaction with acidic potassium permanganate and formaldehyde was explored for the determination of neurotransmitters and their metabolites. The neurotransmitters norepinephrine and dopamine were quantified in the left and right hemispheres of rat hippocampus, nucleus accumbens and prefrontal cortex, and the metabolites vanillylmandelic acid, 3,4-dihydrophenylacetic acid, 5-hydroxyindole-3-acetic acid and homovanillic acid were identified in human urine. Under optimised chemiluminescence reagent conditions, the limits of detection for these analytes ranged from 2.5 × 10(-8) to 2.5 × 10(-7) M. For the determination of neurotransmitter metabolites in urine, a two-dimensional high-performance liquid chromatography (2D-HPLC) separation operated in heart-cutting mode was developed to overcome the peak capacity limitations of the one-dimensional separation. This approach provided the greater separation power of 2D-HPLC with analysis times comparable to conventional one-dimensional separations.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Dopamina/análise , Medições Luminescentes/métodos , Neurotransmissores/análise , Norepinefrina/análise , Animais , Cromatografia Líquida de Alta Pressão/instrumentação , Dopamina/metabolismo , Dopamina/urina , Humanos , Medições Luminescentes/instrumentação , Neurotransmissores/metabolismo , Neurotransmissores/urina , Norepinefrina/metabolismo , Norepinefrina/urina , Permanganato de Potássio/química , Ratos
5.
Bioresour Technol ; 388: 129761, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37696335

RESUMO

Staggering amounts of food waste are produced in Australia, and this review provides food waste based biorefinery opportunities in moving towards a circular economy in Australia. The current food waste scenario in Australia including an overview of primary food waste sources, government regulation, and current management practices is presented. The major food waste streams include fruit and vegetable (waste from wine grapes, citrus, apple, potato, and tomato), nuts (almond processing waste), seafood (Fish waste), dairy whey, sugarcane bagasse, and household and businesses. The composition of these waste streams indicated their potential for use in biorefineries to produce value-added products via various pathways combining direct extraction and biological and thermochemical conversion. Finally, the efforts made in Australia to utilize food waste as a resource, as well as the challenges and future directions to promote the development of concrete and commercially viable technologies for food waste biorefinery, are described.

6.
J Food Sci ; 82(12): 2857-2863, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29135023

RESUMO

This study selected 5 methods, including boiling, hot air drying, high-pressurized steam, freezing, and microwave radiation to pretreat fresh oil palm fruit before solvent extraction of the oil. Using fresh fruit as a control, the pretreatment methods were compared for the effects on the activity of the 2 main enzymes in the fruit and some physicochemical properties of the crude palm oil. The results indicated, although all the 5 pretreatments could inactivate lipase and peroxidase in the treated flesh significantly (P < 0.05), the high-pressurized steam was the most effective. There were also differences in the unsaturated fatty acid contents of the 6 oils. The crude oil from frozen fruit contained significantly more vitamin E (37829.33 ppm) than previously reported. Microwave radiation was shown to significantly decrease the free fatty acid content and the peroxide value, while increasing the oxidative stability index. Thermal behaviors of the oils were significantly different to each other with the exception a few parameters (P < 0.05).


Assuntos
Arecaceae/química , Frutas/química , Óleo de Palmeira/química , Ácidos Graxos não Esterificados/química , Temperatura Alta , Micro-Ondas , Oxirredução
7.
Talanta ; 134: 402-408, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25618686

RESUMO

The selection of two high performance liquid chromatography (HPLC) columns with vastly different retention mechanisms is vital for performing effective two-dimensional (2D-) HPLC. This paper reports on a systematic method to select a pair of HPLC columns that provide the most different separations for a given sample. This was completed with the aid of a HPLC simulator that predicted retention profiles on the basis of real experimental data, which is difficult when the contents of sample matrices are largely-or completely-unknown. Peaks from the same compounds must first be matched between chromatograms to compare the retention profiles and optimised 2D-HPLC column selection. In this work, two methods of matching peaks between chromatograms were explored and an optimal pair of chromatography columns was selected for 2D-HPLC. First, a series of 17 antioxidants were selected as an analogue for a coffee extract. The predicted orthogonality of the standards was 39%, according to the fractional surface coverage 'bins' method, which was close to the actual space utilisation of the standard mixture, 44%. Moreover, the orthogonality for the 2D-HPLC of coffee matched the predicted value of 38%. The second method employed a complex sample matrix of urine to optimise the column selections. Seven peaks were confidently matched between chromatograms by comparing relative peak areas of two detection strategies: UV absorbance and potassium permanganate chemiluminescence. It was found that the optimal combinations had an orthogonality of 35% while the actual value was closer to 30%.

8.
Anal Chim Acta ; 842: 35-41, 2014 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-25127649

RESUMO

Sodium polyphosphate is commonly used to enhance chemiluminescence reactions with acidic potassium permanganate through a dual enhancement mechanism, but commercially available polyphosphates vary greatly in composition. We have examined the influence of polyphosphate composition and concentration on both the dual enhancement mechanism of chemiluminescence intensity and the stability of the reagent under analytically useful conditions. The average chain length (n) provides a convenient characterisation, but materials with similar values can exhibit markedly different distributions of phosphate oligomers. There is a minimum polyphosphate chain length (∼6) required for a large enhancement of the emission intensity, but no further advantage was obtained using polyphosphate materials with much longer average chain lengths. Providing there is a sufficient average chain length, the optimum concentration of polyphosphate is dependent on the analyte and in some cases, may be lower than the quantities previously used in routine detection. However, the concentration of polyphosphate should not be lowered in permanganate reagents that have been partially reduced to form high concentrations of the key manganese(III) co-reactant, as this intermediate needs to be stabilised to prevent formation of insoluble manganese(IV).


Assuntos
Polifosfatos/química , Permanganato de Potássio/química , Indicadores e Reagentes , Luminescência , Medições Luminescentes
9.
Drug Test Anal ; 4(7-8): 675-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22461321

RESUMO

This is the first report of chemiluminescence from the reaction of cannabinoids with acidic potassium permanganate, which we have applied to the high performance liquid chromatography (HPLC) determination of cannabidiol (CBD) in industrial-grade hemp. The intensities of the light-producing reactions with two commercially available cannabinoid standards were compared to that of seven model phenolic analytes. Resorcinol, representing the parent phenolic moiety of the cannabinoid class, was shown to react with the permanganate reagents in a manner more similar to phenol than to its hydroxyphenol positional isomers, pyrocatechol and hydroquinone. Alkyl substituents on the phenolic ring, however, have a considerable impact on emission intensity that is dependent upon the position of the groups and the composition of the permanganate reagent. This analytical approach has potential for the determination of other cannabinoids including Δ(9) -tetrahydrocannabinol in drug-grade cannabis.


Assuntos
Canabidiol/análise , Canabinoides/análise , Cannabis/química , Medições Luminescentes/métodos , Permanganato de Potássio/química , Cromatografia Líquida de Alta Pressão/métodos , Fenóis/análise , Sensibilidade e Especificidade
10.
Nat Nanotechnol ; 3(9): 563-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18772919

RESUMO

Fully exploiting the properties of graphene will require a method for the mass production of this remarkable material. Two main routes are possible: large-scale growth or large-scale exfoliation. Here, we demonstrate graphene dispersions with concentrations up to approximately 0.01 mg ml(-1), produced by dispersion and exfoliation of graphite in organic solvents such as N-methyl-pyrrolidone. This is possible because the energy required to exfoliate graphene is balanced by the solvent-graphene interaction for solvents whose surface energies match that of graphene. We confirm the presence of individual graphene sheets by Raman spectroscopy, transmission electron microscopy and electron diffraction. Our method results in a monolayer yield of approximately 1 wt%, which could potentially be improved to 7-12 wt% with further processing. The absence of defects or oxides is confirmed by X-ray photoelectron, infrared and Raman spectroscopies. We are able to produce semi-transparent conducting films and conducting composites. Solution processing of graphene opens up a range of potential large-area applications, from device and sensor fabrication to liquid-phase chemistry.


Assuntos
Grafite/síntese química , Transição de Fase , Grafite/química , Pirrolidinonas/química , Análise Espectral/métodos
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