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1.
Sci Adv ; 7(14)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33789891

RESUMO

Gene replacement approaches are leading to a revolution in the treatment of previously debilitating monogenic neurological conditions. However, the application of gene therapy to complex polygenic conditions has been limited. Down-regulation or dysfunction of receptor expression in the disease state or in the presence of excess ligand has been shown to compromise therapeutic efficacy. Here, we offer evidence that combined overexpression of both brain-derived neurotrophic factor and its receptor, tropomyosin receptor kinase B, is more effective in stimulating axonal transport than either receptor administration or ligand administration alone. We also show efficacy in experimental glaucoma and humanized tauopathy models. Simultaneous administration of a ligand and its receptor by a single gene therapy vector overcomes several problems relating to ligand deficiency and receptor down-regulation that may be relevant to multiple neurodegenerative diseases. This approach shows promise as a strategy to target intrinsic mechanisms to improve neuronal function and facilitate repair.


Assuntos
Transporte Axonal , Neurônios , Suplementos Nutricionais , Terapia Genética , Ligantes , Neurônios/metabolismo
2.
Nat Commun ; 11(1): 5614, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154382

RESUMO

Adult mammalian central nervous system axons have intrinsically poor regenerative capacity, so axonal injury has permanent consequences. One approach to enhancing regeneration is to increase the axonal supply of growth molecules and organelles. We achieved this by expressing the adaptor molecule Protrudin which is normally found at low levels in non-regenerative neurons. Elevated Protrudin expression enabled robust central nervous system regeneration both in vitro in primary cortical neurons and in vivo in the injured adult optic nerve. Protrudin overexpression facilitated the accumulation of endoplasmic reticulum, integrins and Rab11 endosomes in the distal axon, whilst removing Protrudin's endoplasmic reticulum localization, kinesin-binding or phosphoinositide-binding properties abrogated the regenerative effects. These results demonstrate that Protrudin promotes regeneration by functioning as a scaffold to link axonal organelles, motors and membranes, establishing important roles for these cellular components in mediating regeneration in the adult central nervous system.


Assuntos
Axônios/fisiologia , Sistema Nervoso Central/fisiologia , Retículo Endoplasmático/metabolismo , Regeneração Nervosa , Proteínas de Transporte Vesicular/metabolismo , Animais , Axônios/metabolismo , Células Cultivadas , Retículo Endoplasmático/genética , Endossomos/metabolismo , Feminino , Humanos , Integrinas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Regeneração Nervosa/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/fisiologia , Fármacos Neuroprotetores/administração & dosagem , Traumatismos do Nervo Óptico/tratamento farmacológico , Traumatismos do Nervo Óptico/metabolismo , Traumatismos do Nervo Óptico/patologia , Fosforilação , Domínios Proteicos , Ratos , Ratos Sprague-Dawley , Retina/efeitos dos fármacos , Retina/fisiologia , Proteínas de Transporte Vesicular/administração & dosagem , Proteínas de Transporte Vesicular/química , Proteínas de Transporte Vesicular/genética
3.
Reprod Fertil Dev ; 19(4): 553-62, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17524300

RESUMO

Scottish Blackface ewes from cobalt-deficient farmland were fed a diet containing 0.06 mg cobalt per kg dry matter from approximately 30 days before embryo recovery/transfer until lambing. Ewes remained untreated (-Co; n = 82) or were given an intraruminal cobalt-containing bolus to compensate for the dietary deficit (+Co; n = 82). Ewes used as embryo donors (-Co, n = 17; +Co, n = 16) were artificially inseminated with semen from a single Suffolk sire. Day 6 embryos obtained from -Co and +Co donors were transferred in singleton to -Co and +Co recipients in a 2 x 2 factorial-designed experiment to determine the effects of cobalt/vitamin B12 status during the periconception period (factor 1) and pregnancy (factor 2) on lamb viability at birth. Mean (+/- s.e.m.) circulating concentrations of vitamin B12 in -Co and +Co donors at ovum recovery were 182 +/- 10 and 1288 +/- 64 pmol L(-1), respectively (P < 0.001), and the number of corpora lutea per ewe ovulating was 9.9 +/- 1.6 and 14.4 +/- 1.3, respectively (P < 0.05). Treatment did not affect the proportion of recovered ova that contained >32 cells (viable) or the median stage of development (late morula), but viable ova recovered from -Co v. +Co ewes had a better morphological grade (2.0 +/- 0.1 v. 2.20 +/- 0.04, respectively; P < 0.01). There was no effect of treatment on the proportion of recipient ewes that became pregnant. Circulating concentrations of vitamin B12 were lower in -Co than +Co ewes during pregnancy (P < 0.001) and at birth in lambs born to -Co ewes compared with those born to +Co ewes (P < 0.001). There was no effect of donor or recipient cobalt/vitamin B12 status on lamb birthweight, neonatal vigour or neonatal rectal temperatures, but lambs derived from +Co v. -Co embryo donors were more active in the first 3 days after birth (P < 0.05). Results show that sub-clinical cobalt/vitamin B12 deficiency reduces ovulatory response in superovulated ewes and that periconception nutrition can affect neonatal lamb behaviour.


Assuntos
Animais Recém-Nascidos/fisiologia , Cobalto/deficiência , Fertilidade , Óvulo/crescimento & desenvolvimento , Carneiro Doméstico/crescimento & desenvolvimento , Deficiência de Vitamina B 12 , Animais , Animais Recém-Nascidos/psicologia , Comportamento Animal , Peso Corporal , Cobalto/administração & dosagem , Dieta , Transferência Embrionária , Feminino , Óvulo/efeitos dos fármacos , Parto , Gravidez , Carneiro Doméstico/metabolismo , Superovulação , Vitamina B 12/administração & dosagem , Vitamina B 12/sangue
4.
Phytomedicine ; 32: 37-40, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28732806

RESUMO

BACKGROUND: Dried leaf Artemisia annua (DLA) has shown efficacy against Plasmodium sp. in rodent studies and in small clinical trials. Rodent malaria also showed resiliency against the evolution of artemisinin drug resistance. PURPOSE: This is a case report of a last resort treatment of patients with severe malaria who were responding neither to artemisinin combination therapy (ACT) nor i.v. artesunate. STUDY DESIGN: Of many patients treated with ACTs and i.v. artesunate during the 6 mon study period, 18 did not respond and were subsequently treated with DLA Artemisia annua. METHODS: Patients were given a dose of 0.5g DLA per os, twice daily for 5d. Total adult delivered dose of artemisinin was 55mg. Dose was reduced for body weight under 30kg. Clinical symptoms, e.g. fever, coma etc., and parasite levels in thick blood smears were tracked. Patients were declared cured and released from hospital when parasites were microscopically undetectable and clinical symptoms fully subsided. RESULTS: All patients were previously treated with Coartem® provided through Santé Rurale (SANRU) and following the regimen prescribed by WHO. Of 18 ACT-resistant severe malaria cases compassionately treated with DLA, all fully recovered. Of the 18, this report details two pediatric cases. CONCLUSIONS: Successful treatment of all 18 ACT-resistant cases suggests that DLA should be rapidly incorporated into the antimalarial regimen for Africa and possibly wherever else ACT resistance has emerged.


Assuntos
Antimaláricos/farmacologia , Artemisia annua/química , Artemisininas/farmacologia , Malária/tratamento farmacológico , Administração Intravenosa , Adolescente , Adulto , Combinação Arteméter e Lumefantrina , Artemisininas/administração & dosagem , Artesunato , Criança , Pré-Escolar , Combinação de Medicamentos , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Etanolaminas/farmacologia , Feminino , Fluorenos/farmacologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Folhas de Planta/química , Comprimidos/química , Resultado do Tratamento , Adulto Jovem
5.
J Pharm Pharmacol ; 54(9): 1257-63, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12356280

RESUMO

Previous work has demonstrated the capability of near-infrared (NIR) spectroscopy to determine the cineole content (not less than 70% w/w) of eucalyptus oil with an accuracy comparable with that of the British Pharmacopoeia (BP) assay method. The aim of the present study was to determine if the same method was capable of quantifying other chemical constituents at similar levels in essential oils and also to ascertain if NIR spectroscopy can accurately quantify compounds present at much lower levels in essential oils. Lemongrass oil contains citral at concentrations of approximately 65-85% w/w, and lemon oil contains citral at a concentration of approximately 2-5% w/w. A total of 26 samples of pure lemongrass oil and 35 samples of pure lemon oil (both including samples that were "spiked" with citral to increase the calibration range) were scanned on the FOSS NIRSystems 6500 Rapid Content Sampler using a reflectance vessel as sample presentation method. The reference method for both types of oil was the BP monograph titration assay for the citral content of lemon oil and calibrations were constructed using these reference data. For the lemongrass oils, the mean accuracy was found to be 1.00% or less and the mean bias was 0.09% or less. For the lemon oils, the mean accuracy was found to be 4.28% or less and the mean bias was -0.71% or less. The NIR method developed was rapid, simple and non-destructive and may prove beneficial for the accurate determination of the citral content of lemongrass oils and for the approximate citral content of lemon oils.


Assuntos
Monoterpenos/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Monoterpenos Acíclicos , Cymbopogon/química , Gorduras Insaturadas na Dieta/análise , Valores de Referência
6.
Talanta ; 79(3): 657-64, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19576426

RESUMO

Recent developments in Hyperspectral Imaging equipment have made possible the use of this analytical technique for fast scanning of sample surfaces. This technique has turned out to be especially useful in Pharmacy, where information about the distribution of the components in the surface of a tablet can be obtained. One particular application of Hyperspectral Chemical Imaging is the search for singularities inside pharmaceutical tablets, e.g. coating defects. Nevertheless, one problem has to be faced: how to analyze a sample without any previous knowledge about it, or having only the minimum information about the tablet. In this work a new methodology, based on correlation coefficients, is introduced to obtain valuable information about one Hyperspectral Image (detection of defects, punctual contaminants, etc.) without any previous knowledge. The methodology combines Principal Component Analysis (PCA), correlation coefficient between one specific pixel included in the image and the rest of the image; and a new enhanced contrast function to obtain more selective chemical and spatial information about the image. To illustrate the applicability of the proposed methodology, real tablets of ibuprofen have been studied. The proposed methodology is presented as a control technique to detect batch variability, defects in final tablets and punctual contaminants, being a potential supplementary tool for quality controls. In addition, the usefulness of the proposed methodology is not exclusive to NIR-CI devices, but to any hyperspectral and multivariate image system.


Assuntos
Preparações Farmacêuticas/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Ibuprofeno/química , Análise de Componente Principal , Propriedades de Superfície , Comprimidos
7.
Rev Sci Instrum ; 79(10): 10E919, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19044574

RESUMO

The distance radiation waves that supersonically propagate in optically thick, diffusive media are energy sensitive. A blast wave can form in a material when the initially diffusive, supersonic radiation wave becomes transonic. Under specific conditions, the blast wave is visible with radiography as a density perturbation. [Peterson et al., Phys. Plasmas 13, 056901 (2006)] showed that the time-integrated drive energy can be measured using blast wave positions with uncertainties less than 10% at the Z Facility. In some cases, direct measurements of energy loss through diagnostic holes are not possible with bolometric and x-ray radiometric diagnostics. Thus, radiography of high compression blast waves can serve as a complementary technique that provides time-integrated energy loss through apertures. In this paper, we use blast waves to characterize the energy emerging through a 2.4 mm aperture and show experimental results in comparison to simulations.

8.
J Nat Prod ; 66(11): 1486-9, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14640524

RESUMO

The naturally occurring bitter principle quassin (1) was converted chemically into the gamma-lactone quassilactone (13) in an attempt to enhance its antiplasmodial activity. The in vitro antiplasmodial activity of 13 against Plasmodium falciparum (K1) (IC(50) = 23 microM) was 40-fold greater than that of 1. However, one of the intermediates, compound 8, the 15beta-hydroxy,16-O-m-chlorobenzoyl analogue of 1, was 506-fold more active than 1 against P. falciparum (IC(50) = 1.8 microM) and only 3-fold less potent than chloroquine. In addition, 8 displayed the best cytotoxic/antiplasmodial ratio (112) of all of the compounds tested. In the course of this work a dimer, neoquassin ether (6), linked at C-16 was also prepared; 6 was found to have weak antiplasmodial activity (IC(50) = 9.7 microM).


Assuntos
Antimaláricos/química , Antimaláricos/farmacologia , Lactonas/química , Lactonas/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Quassinas/química , Quassinas/farmacologia , Animais , Concentração Inibidora 50 , Estrutura Molecular , Relação Estrutura-Atividade
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