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1.
Opt Express ; 16(5): 3342-8, 2008 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-18542424

RESUMO

We demonstrate high spatial resolution phase retrieval of a non-periodic gold nano-structure using the method of Fresnel coherent diffractive imaging. The result is quantitative to better than 10% and does not rely on any a priori knowledge of the sample.


Assuntos
Teste de Materiais/métodos , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Refratometria/métodos , Tomografia de Coerência Óptica/métodos , Difração de Raios X/métodos
2.
Transfus Clin Biol ; 15(1-2): 72-81, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18501653

RESUMO

The most deadly of the human malaria parasites, Plasmodium falciparum, invades the erythrocytes of its host and initiates a remarkable series of morphological rearrangements within the host cell cytoplasm. The mature erythrocyte is effectively a floating sack of haemoglobin with no endogenous protein synthesis or protein trafficking machinery. In order to colonise and remodel its extracellular space, the parasite generates a series of novel structures that are involved in the export of virulence factors to the surface of the host cell. These include extensions of the parasite's vacuolar membrane, known as the tubulovesicular network, and structures referred to as Maurer's clefts. Maurer's clefts are convoluted collections of distorted discs that are tethered to the red blood cell membrane by structures with stalk-like profiles. Recently electron tomography has enabled visualisation--in three dimensions and at unprecedented resolution--the complexity of the membrane systems within the infected RBC cytoplasm.


Assuntos
Eritrócitos/parasitologia , Eritrócitos/ultraestrutura , Malária Falciparum/patologia , Plasmodium falciparum/ultraestrutura , Animais , Microscopia Eletrônica/métodos , Transporte Proteico , Proteínas de Protozoários/análise , Proteínas de Protozoários/metabolismo
3.
Forensic Sci Int Genet ; 34: 105-115, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29453107

RESUMO

In a previous study we presented an assay for targeted mRNA sequencing for the identification of human body fluids, optimised for the Illumina MiSeq/FGx MPS platform. This assay, together with an additional in-house designed assay for the Ion Torrent PGM/S5 platform, was the basis for a collaborative exercise within 17 EUROFORGEN and EDNAP laboratories, in order to test the efficacy of targeted mRNA sequencing to identify body fluids. The task was to analyse the supplied dried body fluid stains and, optionally, participants' own bona fide or mock casework samples of human origin, according to specified protocols. The provided primer pools for the Illumina MiSeq/FGx and the Ion Torrent PGM/S5 platforms included 33 and 29 body fluid specific targets, respectively, to identify blood, saliva, semen, vaginal secretion, menstrual blood and skin. The results demonstrated moderate to high count values in the body fluid or tissue of interest with little to no counts in non-target body fluids. There was some inter-laboratory variability in read counts, but overall the results of the laboratories were comparable in that highly expressed markers showed high read counts and less expressed markers showed lower counts. We performed a partial least squares (PLS) analysis on the data, where blood, menstrual blood, saliva and semen markers and samples clustered well. The results of this collaborative mRNA massively parallel sequencing (MPS) exercise support targeted mRNA sequencing as a reliable body fluid identification method that could be added to the repertoire of forensic MPS panels.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , RNA Mensageiro/metabolismo , Análise Química do Sangue , Muco do Colo Uterino/química , Feminino , Marcadores Genéticos , Humanos , Laboratórios , Análise dos Mínimos Quadrados , Masculino , Menstruação , Saliva/química , Sêmen/química , Pele/química
4.
J Clin Endocrinol Metab ; 70(5): 1254-61, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2186055

RESUMO

Twenty-six acromegalic patients were randomized to treatment with either SMS 201-995 or bromocriptine in increasing doses and were investigated before treatment, after 2, 4, and 8 weeks of treatment, and 2 weeks after discontinuation of treatment. There were two dropouts from the bromocriptine group and one from the SMS 201-995 group. Amelioration of clinical signs and symptoms was seen in both groups during treatment. After 8 weeks mean 12-h GH concentrations had declined from 13.8 +/- 5.2 to 2.9 +/- 4.4 (mean +/- SEM) in SMS 201-995-treated and from 18.8 +/- 7.5 to 5.4 +/- 1.2 micrograms/L in bromocriptine-treated patients. Somatomedin-C concentrations fell from 3.04 +/- 0.36 to 1.43 +/- 0.36 in SMS 201-995-treated and from 2.93 +/- 0.40 to 2.13 +/- 0.27 U/mL in bromocriptine-treated patients. Size reduction of the pituitary tumor was seen in one patient receiving bromocriptine. Gastrointestinal glucose absorption was delayed, and insulin secretion suppressed during treatment with SMS 201-995. Hemoglobin-A1 concentrations remained unchanged in SMS 201-995-treated patients, but declined in the bromocriptine group. Side-effects were common, but usually tolerable, with both treatments. It is concluded that both drugs are of benefit in the treatment of acromegaly.


Assuntos
Acromegalia/tratamento farmacológico , Bromocriptina/uso terapêutico , Octreotida/uso terapêutico , Acromegalia/sangue , Acromegalia/patologia , Adulto , Glicemia/análise , Bromocriptina/efeitos adversos , Feminino , Hormônio do Crescimento/sangue , Humanos , Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Masculino , Pessoa de Meia-Idade , Octreotida/efeitos adversos , Cooperação do Paciente , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Matrix Biol ; 20(2): 77-85, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11334709

RESUMO

Zonular fibers are a specific form of extracellular matrix composed mainly of fibrillins. The purpose of this study was to determine which cells secrete fibrillin-1 during development and aging. A specific guinea pig fibrillin-1 mRNA probe was designed and cloned in order to identify fibrillin-secreting cells in guinea pig eye, using in situ hybridization. Immunofluorescence, with a specific guinea pig monoclonal antibody, was used to compare protein levels at different stages from birth to 35 months of age. Electron microscopy and immunolabeling were used to investigate the organization of zonular microfibril bundles. We identified the cells of non-pigmented epithelium of the ciliary body as the main source of fibrillin secreted into the zonule. Moreover, while mRNA expression decreased during aging, there was no decrease in fibrillin immunoreactivity, as previously described in human aorta. These data indicate a very slow turnover of the zonular microfibrils which can be correlated with the appearance during aging of a new periodic fibrillar structure. This new structure may reflect an increased cross-linking in the long-lived zonular microfibrillar bundles.


Assuntos
Envelhecimento/metabolismo , Matriz Extracelular/metabolismo , Proteínas dos Microfilamentos/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar , Matriz Extracelular/ultraestrutura , Olho/crescimento & desenvolvimento , Olho/metabolismo , Fibrilina-1 , Fibrilinas , Cobaias , Humanos , Immunoblotting , Hibridização In Situ , Camundongos , Camundongos Endogâmicos BALB C , Proteínas dos Microfilamentos/genética , Microscopia Eletrônica/métodos , Dados de Sequência Molecular
6.
J Med Chem ; 25(2): 145-52, 1982 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7057419

RESUMO

Substituted benzoic acid esters of 1-methyl-4-piperidinol showed analgesic activity when assayed by the mouse hot-plate methods, the more potent ones falling in the morphine-codeine range. To understand how substituents on the aromatic ring affect the analgesic potency, quantitative structure-activity correlations were carried out on a series of 44 derivatives. Among the various substituent parameters included in the study, Lortho (Length of ortho-substituents) and B1 (minimal width of substituents) or E8 at meta and para positions gave negative correlation with the potency, while lipophilicity (especially pi meta) and the ability of being a hydrogen-bond acceptor enhanced the potency. Based on the QSAR results, a substitution pattern of the phenyl group was defined for optimal activity. Implications on drug-receptor interactions and the possible binding mode of these compounds were discussed.


Assuntos
Analgésicos/síntese química , Piperidinas/síntese química , Animais , Fenômenos Químicos , Físico-Química , Ligação de Hidrogênio , Meperidina/farmacologia , Camundongos , Conformação Molecular , Morfina/farmacologia , Piperidinas/farmacologia , Tempo de Reação/efeitos dos fármacos , Relação Estrutura-Atividade
7.
Brain Res ; 585(1-2): 340-2, 1992 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-1355003

RESUMO

The release of the excitatory amino acids glutamate and aspartate from human neocortex was investigated in vitro by utilizing brain tissue removed during anterior temporal lobectomies for tumor or epilepsy. Depolarization (50 mM K+) increased the glutamate release to 291% of control (809 pmol/mg/min) during blocked synaptic transmission and to 669% (1859 pmol/mg/min) when synaptic transmission was not blocked. Aspartate release increased to 141% (326 pmol/mg/min) and 178% (412 pmol/mg/min) respectively. The difference between release with and without blocked synaptic transmission was statistically significant only for glutamate (P less than 0.01). These data provides evidence for a Ca(2+)-dependent release of glutamate, supporting a possible role of this amino acid as a neurotransmitter in human neocortex.


Assuntos
Cálcio/fisiologia , Córtex Cerebral/metabolismo , Glutamatos/metabolismo , Ácido Aspártico/metabolismo , Ácido Glutâmico , Humanos , Técnicas In Vitro , Bloqueio Nervoso , Sinapses/fisiologia , Transmissão Sináptica
8.
J Nat Prod ; 43(6): 736-8, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20707397

RESUMO

The unnatural thebaine analog, oripavine 3-ethyl ether, was efficiently metabolized to morphine 3-ethyl ether and morphine in the opium poppy. An attempt to detect oripavine hy an isotope dilution experiment based on its presumed biosynthesis from reticuline was unsuccessful.


Assuntos
Papaver/química , Papaverina , Plantas Medicinais/química , Estrutura Molecular , Papaver/metabolismo , Papaverina/análogos & derivados , Papaverina/biossíntese , Papaverina/química
9.
J Pharm Sci ; 64(6): 1040-1, 1975 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1133725

RESUMO

A protoberberine alkaloid was isolated from opium and characterized as (-) 2, 10-dihydroxy-3,9-dimethoxytetrahydroprotoberberine by spectroscopic methods and by comparison with (-) stepholidine.


Assuntos
Alcaloides de Berberina/análise , Berberina/análogos & derivados , Cromatografia em Camada Fina , Espectrometria de Massas
10.
J Pharm Sci ; 67(1): 103-6, 1978 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-619094

RESUMO

Administration of 1-3H-N-methyl-14C-(+/-)-reticuline to Papaver bracteatum gave good incorporation of carbon-14 into thebaine and a decrease in the tritium to carbon-14 ratio indicative of racemization. The incorporation of carbon-14 and the extent of tritium loss were the same whether reticuline was administered to the intact plant or to isolated leaves. Carrier dilution with cold codeine, codeinone, and morphine showed only insignificant incorporation of radioactivity into codeine and none at all into codeinone and morphine. When codeinone was administered to the living plant, it was converted to codeine rapidly and efficiently, but no O-demethylation to morphine could be detected. The experimental data indicate that the biosynthesis of thebaine in P. bracteatum proceeds by the same pathway as in the opium poppy. The limiting step in the sequence is the demethylation of the enol ether group of thebaine to neopinone.


Assuntos
Derivados da Morfina/biossíntese , Papaver/metabolismo , Plantas Medicinais , Codeína/análogos & derivados , Codeína/metabolismo , Derivados da Morfina/isolamento & purificação , Papaver/anatomia & histologia , Reticulina/metabolismo , Tebaína/metabolismo
11.
Clin Neurol Neurosurg ; 94(1): 25-30, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1321694

RESUMO

Data from 27 thalamotomies were analyzed with respect to possible correlations between certain intra-operative observations and the long-term effect on parkinsonian tremor. Tremor reduction caused by mechanical impact of the electrodes in the target area was not correlated with the long-term effect on the tremor. The same was true for the threshold intensities during the intra-operative electrical stimulation of the target area, stimulation that facilitates and/or inhibits the tremor. In a minority of the patients, all with good long-term results, a combination of a pronounced tremor inhibition from the electrode insertion and a low threshold intensity was observed. Variations in other lesion parameters were not correlated with the outcome. The results are discussed within the framework of a "tremor" vs. a "tonus" mechanism underlying the thalamotomy effect.


Assuntos
Doença de Parkinson/cirurgia , Complicações Pós-Operatórias/fisiopatologia , Técnicas Estereotáxicas , Núcleos Talâmicos/cirurgia , Tremor/cirurgia , Idoso , Mapeamento Encefálico , Eletrodiagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Núcleos Talâmicos/fisiopatologia , Tremor/fisiopatologia
12.
Acta Neurochir Suppl ; 72: 107-21, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10337418

RESUMO

The purpose of this paper is to present the results, assessed by an independent observer, of surgical treatment of 428 consecutive patients harbouring aneurysms of the anterior circulation, together with a review of relevant anatomy and operative strategy. At follow-up (mean 5.6 years) 89.3% lived at home and were independent, 5.1% lived at home but needed some kind of assistance, 2.0% lived in institution, whereas information was unavailable in 3.6% of living patients. Two hundred and fifty-three patients (64.5%) had unchanged employment status, 0.3% worked in sheltered environment, whereas 30.9% went out of work due to their subarachnoid hemorrhage (SAH). Information about employment status was unavailable in 4.3%. For aneurysms of the internal carotid, anterior communicating and middle cerebral artery, respectively, mortality was 3.2, 3.9 and 5.6%, whereas 92.0, 88.1 and 89.0% of surviving patients lived at home and were independent and 67.0, 63.6 and 63.0% had unchanged employment status. Three-months mortality of all causes was 4.2%. In the postoperative period 53 (12.4%) patients developed clinical signs of vasospasms, 6 (1.4%) had cardiac infarction, 4 (0.9%) lung oedema, 4 (0.9%) deep vein thrombosis, and 7 patients (1.6%) infection. During the follow-up period shunt-dependent hydrocephalus developed in 4.2% and 0.2% had a subsequent SAH from the same aneurysm. Forty-three patients were on anticonvulsive therapy.


Assuntos
Encéfalo/irrigação sanguínea , Artéria Carótida Interna/cirurgia , Aneurisma Intracraniano/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Hemorragia Subaracnóidea/cirurgia , Resultado do Tratamento
13.
J Submicrosc Cytol Pathol ; 30(3): 365-9, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9723196

RESUMO

Ageing is marked by ultrastructural and functional changes in most tissues. In part, these changes are caused by a loss of elasticity in the elastic fibers of the extracellular matrix. These fibers are composed of the protein elastin associated with microfibrils of 8 to 12 nm in diameter. Microfibrils contain fibrillins as major constituents. Mutations in fibrillin genes are considered as primary causes of Marfan syndrome, a genetic disorder with pathological manifestations in the cardiovascular and skeletal systems, in addition to dysfunctions in the eye. Fibrillin is also the major protein of the ciliary zonule fibers. During ageing, these fibers become more fragile, and concomitantly, an increased risk for ocular pathologies is observed. We have investigated structural modifications in fibrillin-rich microfibrils during ageing of human ciliary zonule. Observations using light microscopy and transmission electron microscopy after rotary shadowing allowed us to describe the organization of the zonule fibers and their insertion into the ciliary body. Our results emphasize qualitative differences between young and old zonules, which are likely due to modifications in the structure of microfibrils.


Assuntos
Citoesqueleto de Actina/fisiologia , Citoesqueleto de Actina/ultraestrutura , Envelhecimento/fisiologia , Corpo Ciliar/crescimento & desenvolvimento , Corpo Ciliar/ultraestrutura , Proteínas dos Microfilamentos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Elasticidade , Proteínas da Matriz Extracelular/metabolismo , Fibrilinas , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Proteínas dos Microfilamentos/análise , Microscopia Eletrônica
19.
J Pharm Sci ; 55(7): 743-4, 1966 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-5967757
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