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1.
Eur J Paediatr Neurol ; 21(5): 703-706, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28549726

RESUMO

OBJECTIVE: Cerebral palsy (CP) can be classified as spastic, dyskinetic, ataxic or combined. Correct classification is essential for symptom-targeted treatment. This study aimed to investigate agreement among professionals on the phenotype of children with CP based on standardized videos. METHODS: In a prospective, observational pilot study, videos of fifteen CP patients (8 boys, mean age 11 ± 5 y) were rated by three pediatric neurologists, three rehabilitation physicians and three movement disorder specialists. They scored the presence and severity of spasticity, ataxia or dyskinesias/dystonia. Inter- and intraobserver agreement were calculated using Cohen's and Fleiss' kappa. RESULTS: We found a fair inter-observer (κ = 0.36) and moderate intra-observer agreement (κ = 0.51) for the predominant motor symptom. This only slightly differed within the three groups of specialists (κ = 0.33-0.55). CONCLUSION: A large variability in the phenotyping of CP children was detected, not only between but also within clinicians, calling for a discussing on the operational definitions of spasticity, dystonia and ataxia. In addition, the low agreement found in our study questions the reliability of use of videos to measure intervention outcomes, such as deep brain stimulation in dystonic CP. Future studies should include functional domains to assess the true impact of management options in this highly challenging patient population.


Assuntos
Ataxia/diagnóstico , Paralisia Cerebral/classificação , Paralisia Cerebral/diagnóstico , Distonia/diagnóstico , Espasticidade Muscular/diagnóstico , Adolescente , Ataxia/etiologia , Paralisia Cerebral/complicações , Criança , Diagnóstico Diferencial , Distonia/etiologia , Feminino , Humanos , Masculino , Espasticidade Muscular/etiologia , Variações Dependentes do Observador , Projetos Piloto , Estudos Prospectivos , Reprodutibilidade dos Testes , Gravação de Videoteipe
2.
Nervenarzt ; 86(8): 934-46, 2015 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-26122637

RESUMO

Multiple sclerosis (MS) is characterized by oligodendrocyte death and myelin sheath destruction of the central nervous system (CNS) in response to autoinflammatory processes. Besides demyelination axonal degeneration constitutes the second histopathological hallmark of this disease. A large number of immunomodulatory and targeted immunosuppression treatments have been approved for relapsing remitting (RR) MS where they effectively reduce relapse rates; however, currently no treatment options exist to repair injured axonal tracts or myelin damage that accumulates over time particularly in progressive MS. In light of the growing available therapeutic repertoire of highly potent immunomodulatory medications there is an increasing interest in the development of therapies aimed at neutralizing neurodegenerative damage. Endogenous remyelination processes occur mainly as a result of oligodendrocyte precursor cell (OPC) activation, recruitment and maturation; however, this repair activity appears to be limited and increasingly fails during disease progression. Based on these observations OPCs are considered as promising targets for the regenerative treatment of all stages of MS. This article presents an overview of approved medications with a suggested role in regeneration, regenerative treatments that are currently being tested in clinical trials, as well as promising future therapeutic approaches derived from basic glial cell research aiming at the promotion of the endogenous repair activity of the brain.


Assuntos
Fatores Imunológicos/uso terapêutico , Imunossupressores/uso terapêutico , Esclerose Múltipla/terapia , Regeneração Nervosa/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Oligodendroglia/efeitos dos fármacos , Humanos
3.
J Chem Phys ; 140(12): 124308, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24697442

RESUMO

Of the six normal vibrations of SF6, ν3 has a key role in the mechanisms of radiative forcing. This vibration, though inactive in Raman, shows up through the transition 2ν3 allowing for a complementary view on the asymmetric stretch of the molecule. Here, we look back into this topic, which has already caught some interest in the past but with some points been left out. We make a systematic incoherent-light-scattering analysis of the overtone with the use of different gas pressures and polarization orientations for the incident beam. Absolute-scale isotropic and anisotropic spectra are reported along with natural and pressure-induced widths and shifts, and other spectral features such as the peaks corresponding to the (experimentally indistinguishable) interfering channels Eg and F2g hitherto seen solely as two-photon IR-absorption features. We make the first-ever prediction of the SF6 polarizability second derivative with respect to the ν3-mode coordinate and we develop a heuristic argument to explain why the superposition of the three degenerate stretching motions that are related to the ν3 mode cannot but generate a polarized Raman band.

4.
J Chem Phys ; 140(3): 034308, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25669380

RESUMO

Long known as a fully polarized band with a near vanishing depolarization ratio [ηs = 0.05, W. Holzer and R. Ouillon, Chem. Phys. Lett. 24, 589 (1974)], the 2ν5 Raman overtone of SF6 has so far been considered as of having a prohibitively weak anisotropic spectrum [D. P. Shelton and L. Ulivi, J. Chem. Phys. 89, 149 (1988)]. Here, we report the first anisotropic spectrum of this overtone, at room temperature and for 13 gas densities ranging between 2 and 27 amagat. This spectrum is 10 times broader and 50 times weaker than the isotropic counterpart of the overtone [D. Kremer, F. Rachet, and M. Chrysos, J. Chem. Phys. 138, 174308 (2013)] and its profile much more sensitive to pressure effects than the profile of the isotropic spectrum. From our measurements an accurate value for the anisotropy matrix-element |⟨000020|Δα|000000⟩| was derived and this value was found to be comparable to that of the mean-polarizability 000020α¯000000. Among other conclusions our study offers compelling evidence that, in Raman spectroscopy, highly polarized bands or tiny depolarization ratios are not necessarily incompatible with large polarizability anisotropy transition matrix-elements. Our findings and the way to analyze them suggest that new strategies should be developed on the basis of the complementarity inherent in independent incoherent Raman experiments that run with two different incident-beam polarizations, and on concerted efforts to ab initio calculate accurate data for first and second polarizability derivatives. Values for these derivatives are still rarities in the literature of SF6.

5.
J Chem Phys ; 138(17): 174308, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23656135

RESUMO

The room-temperature isotropic spectrum of SF6 was recorded at the frequency of the 2ν5 overtone by running high-sensitivity incoherent Raman experiments for two independent polarizations of the incident beam and for gas densities varying from 2 to 27 amagat. Weak yet observable pressure effects were found. A transparent analysis of the Raman cross-section problem along with the first-ever prediction of the value of the mean polarizability second derivative ∂(2)α/∂q5(2) are made and the hitherto underestimated role of the hot bands of SF6 is brought to the wider public. The emergence of an analytic hotband factor is shown whose magnitude is dramatically increased with the order of the overtone and the gas temperature and all the more so upon considering low-frequency molecular vibrations. Our formulas, which in the harmonic approximation are exact, are still applicable to real situations provided certain conditions are fulfilled. For nondegenerated modes, generalization to higher order overtones is made, an issue addressing the much challenging problem of the IR-allowed second overtone bands. The content of this paper is also an invitation towards ab initio derivative-calculations for sulfur hexafluoride, especially given the today's needs in interpreting spectra of significance for greenhouse atmospheric issues.

6.
Food Chem ; 136(2): 335-41, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23122067

RESUMO

The quantity of phenols, as well as antioxidant and antimicrobial activities, were investigated in bark of Rhamnus alaternus L., R. fallax Boiss., R. intermedia Steud. et Hochst., and R. pumila Turra from natural stands in Croatia. The most abundant anthraquinones in the investigated extracts were chrysophanol in R. alaternus (3.14 mg/g), emodin in R. pumila (0.339 mg/g), and physcion in R. fallax (2.70 mg/g) and R. intermedia (0.285 mg/g). The species exhibiting the highest antioxidant activity were R. fallax and R. pumila. A positive correlation was observed between total phenolic and flavonoid levels of the extracts and antioxidant activity in some of the assays. All species showed antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Candida albicans, Aspergillus niger and Microsporum gypseum with minimal inhibitory concentrations equal to or below 2.500 mg/mL. The results indicate that the investigated Rhamnus species are a source of anthraquinones and other phenols, which act as multifunctional antioxidants with antimicrobial activity.


Assuntos
Antraquinonas/química , Anti-Infecciosos/química , Antioxidantes/química , Casca de Planta/química , Extratos Vegetais/química , Rhamnus/química , Antraquinonas/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rhamnus/classificação
7.
Mol Ecol Resour ; 13(2): 237-42, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23241161

RESUMO

Hybrid zones are regions where genetically distinct populations meet, mate and produce offspring. In such zones, genetically less compatible gene combinations are usually generated, resulting in reduced fitness, and hybrid zones are often maintained because of continuous removal of unfit genotypes, balanced by gene flow into the zone from the parental populations (and are then referred to as 'tension zones'). Tension zones often display unexpectedly high frequencies of gene variants that are rare outside the zone. Previous work has shown that this 'rare allele phenomenon' is not the result of intragenic recombination or increased mutation rates. Further understanding of the population genetics of the phenomenon requires an approach in which both the numbers of individuals and the numbers of loci is increased. Here, we report an approach using a combination of Illumina next-generation sequencing and mass spectrophotometer genotyping to identify markers that may be used for genome-wide investigations of the rare allele phenomenon. We test this approach on a hybrid zone in the land snail Albinaria hippolyti from Greece.


Assuntos
Técnicas Genéticas , Hibridização Genética , Polimorfismo de Nucleotídeo Único , Caramujos/genética , Alelos , Animais , Fluxo Gênico , Genótipo , Grécia , Caramujos/classificação
8.
Int J Epidemiol ; 41(1): 106-15, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22101166

RESUMO

BACKGROUND: Human epidemiological studies suggest that small size at birth and food deprivation during gestation confer an excess risk of coronary heart diseases (CHD) in adulthood, frequently in a sex-specific manner. Prior epigenetic studies indicate that such prenatal conditions are marked by persistent and sometimes sex-specific changes in DNA methylation. Here, we have investigated the association between DNA methylation and myocardial infarction (MI) at six loci sensitive to prenatal nutrition, anticipating potential sex-specificity. Method Within the placebo group of the PROSPER trial on pravastatin and the risk of CHD, we compared all individuals who were event free at baseline and developed MI during 3 years' follow-up (n = 122) with a similar-sized control group. Methylation at IL10, LEP, ABCA1, IGF2, INS and GNASAS was measured in DNA extracted from leucocytes using mass spectrometry. RESULTS: DNA methylation at GNASAS was modestly higher in MI cases compared with controls (P = 0.030). A significant sex interaction was observed for INS (P = 0.014) and GNASAS (P = 0.031). Higher DNA methylation at these loci was associated with MI among women (INS: +2.5%, P = 0.002; GNASAS: +4.2%, P = 0.001). Hypermethylation at one locus and at both loci was associated with odds ratios (ORs) of 2.8 and 8.6, respectively (P(trend) = 3.0 × 10(-4)). No association was observed among men. CONCLUSIONS: The risk of MI in women is associated with DNA methylation marks at specific loci previously shown to be sensitive to prenatal conditions. This observation may reflect a developmental component of MI.


Assuntos
Metilação de DNA/genética , Epigênese Genética , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/genética , Efeitos Tardios da Exposição Pré-Natal , Idoso , Idoso de 80 Anos ou mais , Feminino , Transtornos da Nutrição Fetal , Seguimentos , Interação Gene-Ambiente , Loci Gênicos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Incidência , Masculino , Infarto do Miocárdio/prevenção & controle , Pravastatina/uso terapêutico , Gravidez , Estudos Prospectivos , Fatores de Risco
9.
Anal Biochem ; 422(2): 74-8, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22197418

RESUMO

DNA methylation, the conversion of cytosine to 5-methylcytosine, is an important epigenetic modification involved in gene regulation. DNA methylation is essential for normal development whereas abnormal methylation has been implicated in pathological conditions including cancer. To evaluate the extent and variation of genome-wide DNA methylation and its changes during cellular differentiation and tumorgenesis as well as the interplay with histone modifications, accurate and reproducible quantification of the genomic DNA methylation level is required. These measurements have so far been achieved only by sophisticated and costly techniques. Here we report the generation of an enzyme-linked immunosorbent assay (methDNA-ELISA) for the accurate quantification of global DNA methylation levels. The linear region of this methDNA-ELISA ranges from 1 to 10%, making it highly suitable for the typical ranges from 2 to 6% in mammalian genomes. This method requires 10 ng of isolated DNA per sample, thus permitting investigation with minimal amounts of DNA previously not applicable for global DNA methylation analysis, e.g., clinical biopsies or cells collected by microdissection.


Assuntos
5-Metilcitosina/metabolismo , DNA/análise , Ensaio de Imunoadsorção Enzimática/métodos , Linhagem Celular Tumoral , Análise Custo-Benefício , Citosina/metabolismo , DNA/genética , DNA/metabolismo , Metilação de DNA/genética , Ensaio de Imunoadsorção Enzimática/economia , Regulação da Expressão Gênica , Genoma Humano , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Espectrometria de Massas por Ionização por Electrospray
10.
Neurobiol Aging ; 32(3): 549.e1-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20096957

RESUMO

Research into the pathologic mechanisms of neurodegenerative diseases has revealed that CREB binding protein (CBP) plays an important role in cognitive dysfunction. Loss of one copy of this gene leads to a syndrome with severe cognitive dysfunction. We investigated the association between four common variants in the CBP gene and cognitive function in 5804 participants of the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER). Baseline associations between genetic variation and cognitive function were assessed with linear regression. Longitudinal associations were assessed with linear mixed models. All analyses were adjusted for sex, age, education, country, version of test, and pravastatin use. The intron 4CT and intron 3AC polymorphisms in the CBP gene were associated with better cognitive performance at baseline and during follow-up. Furthermore, the haplotype with the variant alleles of these two polymorphisms also showed a protective effect on cognitive function in all cognitive domains (all p<0.03). Genetic variation in the CBP gene is associated with better cognitive performance in an elderly population. Future research is necessary to investigate the effect of these polymorphisms on the expression of CBP levels and how these polymorphisms affect the gene expression mediated by CBP.


Assuntos
Proteína de Ligação a CREB/genética , Cognição/fisiologia , Epigenômica , Polimorfismo de Nucleotídeo Único/genética , Doenças Vasculares/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Cognição/efeitos dos fármacos , Feminino , Frequência do Gene , Genótipo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Modelos Lineares , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Pravastatina/uso terapêutico , Doenças Vasculares/tratamento farmacológico
11.
Food Chem Toxicol ; 48(8-9): 2176-80, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20488218

RESUMO

Antioxidant activities of the ethanolic extracts of roots, twigs and leaves of common barberry (Berberis vulgaris L.) and Croatian barberry (Berberis croatica Horvat) were studied. All the extracts were found to possess some radical-scavenging and antioxidant activities, as determined by scavenging effect on the DPPH free radical, reducing power and beta-carotene-linoleic acid model system. With the exception of the beta-carotene-linoleic acid test, antioxidant activity correlated well with the content of main plant antioxidants, phenols and flavonols, which suggests an important role of these compounds in overall antioxidant activity of investigated plant organs. The antioxidant activity varied mostly in relation to the organ, while no significant statistically differences were found between B. vulgaris and B. croatica.


Assuntos
Antioxidantes/química , Berberis/química , Fenóis/química , Algoritmos , Compostos de Bifenilo/química , Bósnia e Herzegóvina , Croácia , Flavonóis/análise , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Ácido Linoleico/análise , Oxidantes/química , Fenóis/análise , Picratos/química , Extratos Vegetais/química , beta Caroteno/análise
12.
Food Chem Toxicol ; 48(6): 1537-42, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20304028

RESUMO

Antioxidant and antimicrobial activities as well as the quantity of phenolic substances (total phenol, flavonoid and phenolic acid contents) were determined in aqueous extracts of leaves, stems and flowers of Moltkia petraea (Tratt.) Griseb. from two mountainous localities (Sveti Jure and Snijeznica) in Croatia. In addition, the profile of phenolic acids was analyzed by UPLC-MS/MS. Antioxidant activities of all extracts in different test systems, namely the DPPH radical scavenging, reducing power assay and chelating activity, increased with extract concentration. Activity of the extracts from Snijeznica in beta-carotene-linoleic acid assay did not differ from the activity of standard, BHA. The leaf extracts from Snijeznica demonstrated superior antioxidant activity in most of the assays, while the stem extract from the same locality was the most effective Fe(2+) ion chelator. In general, the extracts from Snijeznica were more effective antioxidants than the corresponding extracts from Sveti Jure. The aqueous extracts of M. petraea did not show antimicrobial activity against bacteria and fungi tested in the diffusion and dilution assays.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Boraginaceae/química , Flores/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Caules de Planta/química , Anti-Infecciosos/isolamento & purificação , Antioxidantes/isolamento & purificação , Cromatografia Líquida , Flavonoides/análise , Testes de Sensibilidade Microbiana , Fenóis/análise , Espectrometria de Massas em Tandem
13.
Food Chem Toxicol ; 48(1): 113-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19786057

RESUMO

Antioxidant and antimicrobial activities, as well as total phenol (TP, Folin-Ciocalteu method) and phenolic acid (UPLC-MS/MS) contents of leaf and flower infusions of Teucrium arduini L. from six different mountainous localities in Croatia (Ucka, Vosac, Sveti Jure, Snjeznica, Vaganac, Susanj) were analysed in this study. Antioxidant capacity was evaluated using the ferric reducing/antioxidant power (FRAP) assay, as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2'-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging assays. The antioxidant potency composite index (ACI), giving equal weight to all three methods used to quantify antioxidant capacity, was the highest for the sample from Vosac (96.7) among flower infusions, while maximum ACI (100) was determined for the infusion from Ucka among leaf infusions. Strong positive correlation was found between the total phenols and ACI for leaf (r=0.953) and flower (r=0.977) infusions. Our results point to significantly (p<0.05) different TP content between leaf and flower infusions, as well as across localities. Leaf infusions of T. arduini from Susanj exhibited marked antibacterial activity against Staphylococcus aureus, while none of the tested infusions exhibited antimicrobial activity against gram-negative bacterial species, or the tested fungal species.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Teucrium/química , Anti-Infecciosos/química , Antioxidantes/química , Bactérias/efeitos dos fármacos , Benzotiazóis/química , Compostos de Bifenilo , Cromanos/farmacologia , Croácia , Compostos Férricos/química , Flores/química , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Fungos/efeitos dos fármacos , Glicosídeos/química , Glicosídeos/farmacologia , Indicadores e Reagentes , Testes de Sensibilidade Microbiana , Fenóis/química , Fenóis/farmacologia , Picratos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Substâncias Redutoras/química , Ácidos Sulfônicos/química
14.
Ann Rheum Dis ; 68(6): 1017-21, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18625619

RESUMO

OBJECTIVES: To replicate a previously reported association with osteoarthritis (OA) of the promoter single nucleotide polymorphism (SNP) rs10980705 in the endothelial differentiation gene 2 (EDG2). METHODS: Five collections of samples, four from Europe and one from China, were studied. They included patients with 3 OA phenotypes: 1501 with knee OA, 1497 with hip OA and 376 with generalised OA. A total of 2521 controls were also studied. Allele and genotype frequencies of the rs10980705 SNP were analysed in each individual sample collection and in pooled data. In addition, a meta-analysis to incorporate results from the original Japanese report was performed. RESULTS: The association of the rs10980705 SNP with knee OA was not replicated in any of the five sample collections studied or in their combined analysis (odds ratio (OR) 1.10, 95% CI 0.98 to 1.22; p = 0.10). Meta-analysis of all data, including the original Japanese study, did show association with knee OA (OR 1.15, 95% CI 1.06 to 1.26; p = 0.002) but the effect was accounted for by the Japanese data and was less significant than the original report. No association was found with hip OA or with generalised OA. CONCLUSIONS: The original report of a promising genetic association between a druggable G-protein coupled receptor, EDG2, and knee OA has not been replicated. This lack of replication could be due to a modest effect of the promoter polymorphism that will require even larger studies (the winners curse) although a more pronounced effect in the Asian population vs Europeans cannot be excluded.


Assuntos
Osteoartrite do Joelho/genética , Polimorfismo de Nucleotídeo Único , Receptores de Ácidos Lisofosfatídicos/genética , Idoso , Povo Asiático/genética , Feminino , Frequência do Gene , Genes Recessivos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , População Branca/genética
15.
J Pharm Sci ; 98(1): 307-18, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18506820

RESUMO

This article describes a procedure to facilitate scale-up for the primary drying phase of lyophilization using a combination of empirical testing and numerical modeling. Freeze dry microscopy is used to determine the temperature at which lyophile collapse occurs. A laboratory scale freeze-dryer equipped with manometric temperature measurement is utilized to characterize the formulation-dependent mass transfer resistance of the lyophile and develop an optimized laboratory scale primary drying phase of the freeze-drying cycle. Characterization of heat transfer at both lab and pilot scales has been ascertained from data collected during a lyophilization cycle involving surrogate material. Using the empirically derived mass transfer resistance and heat transfer data, a semi-empirical computational heat and mass transfer model originally developed by Mascarenhas et al. (Mascarenhas et al., 1997, Comput Methods Appl Mech Eng 148: 105-124) is demonstrated to provide predictive primary drying data at both the laboratory and pilot scale. Excellent agreement in both the sublimation interface temperature profiles and the time for completion of primary drying is obtained between the experimental cycles and the numerical model at both the laboratory and pilot scales. Further, the computational model predicts the optimum operational settings of the pilot scale lyophilizer, thus the procedure discussed here offers the potential to both reduce the time necessary to develop commercial freeze-drying cycles by eliminating experimentation and to minimize consumption of valuable pharmacologically active materials during process development.


Assuntos
Preparações Farmacêuticas/química , Tecnologia Farmacêutica/métodos , Liofilização/métodos , Liofilização/tendências , Tecnologia Farmacêutica/tendências
16.
J Pharm Sci ; 95(3): 517-29, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16447175

RESUMO

This study reviews process modeling efforts which have been developed to elucidate the fundamental physical process underlying the manufacture and delivery of pharmaceutical dosage forms. Within the pharmaceutical industry, process models have been applied to a diverse array of physical processes at length and time scales that vary by orders of magnitude. As such, both large-scale continuum and particle-scale discrete approaches will be discussed in this study. Challenges associated with the practical application of process models within the pharmaceutical industry will be discussed, and opportunities for future research will be identified.


Assuntos
Química Farmacêutica , Modelos Teóricos , Indústria Farmacêutica , Fenômenos Físicos , Física
17.
J Pharm Biomed Anal ; 39(3-4): 837-42, 2005 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15978769

RESUMO

The prevalidation strategy was applied to evaluate UV-vis spectrophotometric procedure with Folin-Ciocalteu's reagent for polyphenols determination. Favourable prevalidation characteristics verified this procedure as a valuable tool in polyphenols analysis and it was successfully applied for determination of total polyphenols and tannins in leaves, stems and flowers of Plantago L. species growing in Croatia. The results showed the variety of total polyphenols content between different plant parts (leaves: up to 10.15%; stems: up to 4.34% and flowers: up to 5.56%). The content of tannins in stems was from 0.28% to 1.00%, while leaves and flowers contained tannins in concentrations of 2.26% and 2.21%, respectively. The results of polyphenols determination were evaluated by using multivariate analysis (UPGMA and PCA) as a contribution to elucidation of relations between different taxa of genus Plantago L.


Assuntos
Química Farmacêutica/métodos , Flavonoides/análise , Fenóis/análise , Plantago/metabolismo , Espectrofotometria/métodos , Indústria Farmacêutica/métodos , Flavonoides/química , Modelos Teóricos , Análise Multivariada , Fenóis/química , Filogenia , Folhas de Planta/metabolismo , Polifenóis , Espectrofotometria Ultravioleta/métodos , Taninos/análise , Raios Ultravioleta
19.
Med Sci Sports Exerc ; 30(9): 1424-9, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9741612

RESUMO

PURPOSE: The purpose of this investigation was to examine the plasma to red blood cell (RBC) lactate concentration ([La]) gradient and RBC:plasma [La] ratio during 30 min of steady-state cycle ergometer exercise at work rates below lactate threshold ( LT. Blood samples were taken from a heated forearm vein, immediately cooled to 4 degrees C in a dry-ice ethanol slurry, and centrifuged at 4 degrees C to separate plasma and RBCs. RESULTS: During >LT, plasma [La] rose to 8.8+/-1.1 mM after 10 min and remained above 6 mM. RBC [La] (4.9+/-0.7 mM) was significantly lower than plasma [La] at 10 min and remained lower throughout exercise. As a result, there was a sizable [La] gradient (approximately 3.5 mM) from plasma to RBC during most of >LT. In LT, the ratio of RBC [La]:plasma [La] was the same for both (0.58+/-0.02) and not significantly different from rest. CONCLUSIONS: These results refuted our hypothesis that the RBC:plasma [La] ratio would decrease at the onset of >LT exercise because of muscle lactate release exceeding the ability of RBCs to take up the lactate. Instead, there appears to be an equilibrium between plasma [La] and RBC [La] in arterialized venous blood from a resting muscle group as evidenced by the constant RBC [La]:plasma [La] ratio.


Assuntos
Exercício Físico/fisiologia , Lactatos/sangue , Adulto , Eritrócitos/química , Teste de Esforço , Humanos
20.
Med Sci Sports Exerc ; 30(4): 536-42, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9565935

RESUMO

PURPOSE: The purpose of this study was to compare the fractional contributions of the three pathways of lactate transport (band 3 system, nonionic diffusion, and monocarboxylate pathway) into red blood cells (RBC) from trained and untrained humans. METHODS: Blood samples were obtained from 19 male subjects: 5 untrained, 5 aerobically-trained, 5 competitive collegiate cross-country runners, and 4 competitive collegiate sprinters. The influx of lactate into the RBC was measured by a radioactive tracer technique using [14C]lactate. Discrimination of each pathway of lactate transport was achieved by using PCMBS (1 mM) to block the monocarboxylate pathway and DIDS (0.2 mM) to block the band 3 system. Nonionic diffusion was calculated as the difference between total lactate influx and the sum of band 3 and monocarboxylate lactate influx. RESULTS: Total lactate influx into the RBC from the more aerobic individuals (trained subjects and cross-country runners) was significantly faster at 1.6 mM lactate concentration ([La]) as compared with the influx into RBC of the untrained subjects. Total influx of lactate was significantly higher (P < 0.05) in the RBC from the sprinters as compared with that in the RBC from the untrained subjects at 41 mM [La]. There were no significant differences among the four groups with regard to the total influx of lactate at 4.1, 8.1, and 20 mM [La]. In general, the percentage of total lactate influx accounted for by each of the three parallel pathways at 1.6, 8.1, and 41.0 mM [La] was not different among the four groups of subjects. CONCLUSIONS: Overall, the groups were more similar than different with regard to RBC lactate influx.


Assuntos
Eritrócitos/química , Exercício Físico/fisiologia , Ácido Láctico/metabolismo , Aptidão Física/fisiologia , Adulto , Transporte Biológico/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia
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