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1.
Intern Med J ; 46(9): 1075-80, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27391386

RESUMO

BACKGROUND: Benzbromarone is a potent uricosuric but is not widely available due to concerns about hepatotoxicity. In Aotearoa New Zealand, benzbromarone has been available since April 2013, subject to funding restrictions, for patients with inadequate urate-lowering response or intolerance to allopurinol and probenecid. AIM: To assess the safety and efficacy of benzbromarone in a real-life setting. METHODS: All patients who received funding for benzbromarone from 1 April 2013 to 30 September 2014 were identified. Prescribers were sent a questionnaire for each individual. Information on demographics, efficacy of previous urate-lowering drugs and reasons for discontinuation were collected. Specific information about the dose, effect on serum urate, adverse effects and liver function tests after commencing benzbromarone was recorded. RESULTS: Completed questionnaires were returned for 123 of 164 (75%) patients. Mean (SD) serum urate prior to benzbromarone was 0.57 (0.12) mmol/L, and estimated glomerular filtration rate was 50.3 (22.8) mL/min/1.73 m(2) . The median dose of benzbromarone was 100 mg/day (25-200 mg/day). Six months after commencing benzbromarone, mean (SD) serum urate was 0.35 (0.12) mmol/L. Benzbromarone-related adverse events included rash (n = 4), diarrhoea (n = 9), nausea (n = 6) and urate stones (n = 3). Liver function test abnormalities were uncommon and tended to be mild. There were 14 patient deaths; none was considered related to benzbromarone. Allopurinol had been prescribed prior to benzbromarone in 117 of 123 patients; median maximum allopurinol dose was 200 mg/day (range 25-600 mg/day), and 19% patients received allopurinol >300 mg/day. CONCLUSION: Benzbromarone provides useful urate-lowering efficacy and does not appear unsafe in patients with gout. Urate-lowering therapy prescribing requires further optimisation.


Assuntos
Benzobromarona/administração & dosagem , Gota/tratamento farmacológico , Uricosúricos/administração & dosagem , Idoso , Alopurinol/uso terapêutico , Benzobromarona/efeitos adversos , Comorbidade , Exantema/etiologia , Feminino , Supressores da Gota/uso terapêutico , Humanos , Testes de Função Renal , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Nova Zelândia , Estudos Retrospectivos , Ácido Úrico/sangue , Uricosúricos/efeitos adversos
2.
Dev Dyn ; 236(4): 1106-14, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17315228

RESUMO

Muscle cell recruitment (hyperplasia) during myogenesis in the vertebrate embryo is known to occur in three consecutive phases. In teleost fish (including zebrafish), however, information on myogenic precursor cell activation is largely fragmentary, and comprehensive characterization of the myogenic phases has only been fully undertaken in a single slow-growing cyprinid species by examination of MEF2D expression. Here, we use molecular techniques to provide a comprehensive characterization of MyoD and Myogenin expression during myogenic cell activation in embryos and larvae of brown trout, a fast-growing salmonid with exceptionally large embryos. Results confirm the three-phase pattern, but also demonstrate that the second and third phases begin simultaneously and progress vigorously, which is different from the previously described consecutive activation of these phases. Furthermore, we suggest that Pax7 is expressed in myogenic progenitor cells that account for second- and third-phase myogenesis. These findings are discussed in relation to teleost myotome development and to teleost growth strategies.


Assuntos
Proliferação de Células , Desenvolvimento Muscular/genética , Proteína MyoD/genética , Miogenina/genética , Truta/embriologia , Truta/genética , Animais , Embrião não Mamífero , Regulação da Expressão Gênica no Desenvolvimento , Fibras Musculares Esqueléticas/citologia , Proteína MyoD/metabolismo , Miogenina/metabolismo , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo
3.
Dev Dyn ; 235(11): 3132-43, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16960856

RESUMO

Present knowledge indicates that fibre recruitment (hyperplasia) in developing teleost fish occurs in three distinct phases. However, the origin and relationship of the myogenic precursors activated during the different phases remains unclear. Here, we address this issue using molecular techniques on embryos and larvae of pearlfish, a large cyprinid species. Results provide comprehensive molecular characterisation of cell recruitment over the three phases of myogenesis, identifying muscle types as they arise. Specifically, we show that the myogenic cells arising during 2nd phase myogenesis are clearly different from the myogenic cells arising during the 3rd phase and that the dermomyotome is a major source of myogenic cells driving 2nd phase hyperplasia. These findings are discussed in relation to their implications for the generality of vertebrate developmental patterns.


Assuntos
Cyprinidae/crescimento & desenvolvimento , Desenvolvimento Muscular , Mioblastos Esqueléticos/fisiologia , Animais , Proliferação de Células , Cyprinidae/genética , Cyprinidae/metabolismo , Expressão Gênica , Desenvolvimento Muscular/genética , Proteína MyoD/análise , Proteína MyoD/genética , Proteína MyoD/metabolismo , Mioblastos Esqueléticos/química , Mioblastos Esqueléticos/metabolismo , Fatores de Regulação Miogênica/análise , Fatores de Regulação Miogênica/genética , Fatores de Regulação Miogênica/metabolismo , Cadeias Pesadas de Miosina/análise , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo , Fator de Transcrição PAX7/análise , Fator de Transcrição PAX7/metabolismo
4.
Anat Embryol (Berl) ; 211(4): 311-22, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16506067

RESUMO

Patterns of initial muscle formation are well documented for teleost fish. Here, attention is focused upon sturgeons, which arose close to the base of the actinopterygian radiation and whose early development has remained largely unresearched. We demonstrate that some features of muscle development are common to both groups of fish, the most important being the origin and form of migration of adaxial cells to establish the superficial slow fibre layer. This, together with information on initial innervation and capillarisation, strongly suggests a common basis for muscle developmental mechanisms among fish. An important feature that is different between sturgeons and teleosts is that sturgeons lack any cellular dorsal-ventral separation of the myotome that involves the insertion of muscle pioneer (MP)-like cells at the site of the future horizontal septum. This, and information from other fish and from sarcopterygians, permits the supposition that such MP-defined dorsal-ventral separation is a teleost apomorphism. These and other findings are discussed in relation to their significance for the evolution of fish muscle developmental patterns.


Assuntos
Evolução Biológica , Peixes/crescimento & desenvolvimento , Desenvolvimento Muscular , Músculo Esquelético/citologia , Animais , Diferenciação Celular , Movimento Celular , Peixes/embriologia , Fibras Musculares Esqueléticas/citologia , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/inervação
5.
Evol Dev ; 8(1): 101-10, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16409387

RESUMO

The somitic compartment that gives rise to trunk muscle and dermis in amniotes is an epithelial sheet on the external surface of the somite, and is known as the dermomyotome. However, despite its central role in the development of the trunk and limbs, the evolutionary history of the dermomyotome and its role in nonamniotes is poorly understood. We have tested whether a tissue with the morphological and molecular characteristics of a dermomyotome exists in nonamniotes. We show that representatives of the agnathans and of all major clades of gnathostomes each have a layer of cells on the surface of the somite, external to the embryonic myotome. These external cells do not show any signs of terminal myogenic or dermogenic differentiation. Moreover, in the embryos of bony fishes as diverse as sturgeons (Chondrostei) and zebrafish (Teleostei) this layer of cells expresses the pax3 and pax7 genes that mark myogenic precursors. Some of the pax7-expressing cells also express the differentiation-promoting myogenic regulatory factor Myogenin and appear to enter into the myotome. We therefore suggest that the dermomyotome is an ancient and conserved structure that evolved prior to the last common ancestor of all vertebrates. The identification of a dermomyotome in fish makes it possible to apply the powerful cellular and genetic approaches available in zebrafish to the understanding of this key developmental structure.


Assuntos
Somitos/citologia , Vertebrados/embriologia , Animais , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Transcrição Box Pareados/genética , Fatores de Transcrição Box Pareados/metabolismo , Filogenia , Vertebrados/genética
6.
Neurology ; 59(8): 1170-82, 2002 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-12391344

RESUMO

OBJECTIVE: To describe the use of large-scale gene expression profiles to distinguish broad categories of myopathy and subtypes of inflammatory myopathies (IM) and to provide insight into the pathogenesis of inclusion body myositis (IBM), polymyositis, and dermatomyositis. METHODS: Using Affymetrix GeneChip microarrays, the authors measured the simultaneous expression of approximately 10,000 genes in muscle specimens from 45 patients in four major disease categories (dystrophy, congenital myopathy, inflammatory myopathy, and normal). The authors separately analyzed gene expression in 14 patients limited to the three major subtypes of IM. Bioinformatics techniques were used to classify specimens with similar expression profiles based on global patterns of gene expression and to identify genes with significant differential gene expression compared with normal. RESULTS: Ten of 11 patients with IM, all normals and nemaline myopathies, and 10 of 12 patients with Duchenne muscular dystrophy were correctly classified by this approach. The various subtypes of inflammatory myopathies have distinct gene expression signatures. Specific sets of immune-related genes allow for molecular classification of patients with IBM, polymyositis, and dermatomyositis. Analysis of differential gene expression identifies as relevant to disease pathogenesis previously reported cytokines, major histocompatibility complex class I and II molecules, granzymes, and adhesion molecules, as well as newly identified members of these categories. Increased expression of actin cytoskeleton genes is also identified. CONCLUSIONS: The molecular profiles of muscle tissue in patients with inflammatory myopathies are distinct and represent molecular signatures from which diagnostic insight may follow. Large numbers of differentially expressed genes are rapidly identified.


Assuntos
Perfilação da Expressão Gênica , Miosite/genética , Análise de Sequência com Séries de Oligonucleotídeos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Lactente , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Família Multigênica , Músculo Esquelético/patologia , Miosite/diagnóstico , Miosite/patologia , Análise de Sequência com Séries de Oligonucleotídeos/métodos
7.
Anat Embryol (Berl) ; 205(2): 113-24, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12021913

RESUMO

Teleost fish are known to develop small populations of muscle fibres that are assumed to be tonic in nature although their contractile properties and many other characteristics remain unknown. Here we attempt to resolve some of the ambiguity and confusions surrounding the definition and functional role of tonic fibres in teleosts and provide new information on their ontogeny. We investigate the differentiation of tonic muscle fibres in three species of cyprinid fish using electron microscopy, histochemistry, immunohistochemistry and in situ hybridization. The fine structure of the fibres defined as tonic in the larvae used in this study complies with patterns known from studies in teleost adults. This allows formal definition of tonic fibres in cyprinid larvae. The tonic fibres may be recognized by a variety of features: (1) by their characteristic position along the medial confines of the red muscle insertion at the horizontal septum, (2) their fine structure, including solid clusters of irregularly cleaved myofibrils, thick and wavy Z-lines, and T-tubules at the A-band/I-band transitions, (3) their histochemical features, specifically weak but obvious staining for mATPase after alkaline preincubation, and lack of SDH activity in the more advanced larval stages, (4) their unique immunological properties, being the only fibre type in the myotome that reacts with a serum against chicken tonic myosin (anti- T2). Expression of tonic characters usually begins within a few fibres in the dorsal domain of the superficial red muscle insertion at the horizontal septum and hence involves a high degree of dorso-ventral polarity. The present evidence indicates that tonic fibres arise from separate myogenic stem cells rather than by transdifferentiation from existing red fibres. First appearance of tonic fibres during ontogeny correlates closely with the onset of free swimming and exogeneous feeding. We use this fact to argue that tonic fibres are probably a prerequisite for efficient locomotory control during prey capture, shoaling and predator avoidance.


Assuntos
Cyprinidae/fisiologia , Fibras Musculares de Contração Lenta/citologia , Músculo Esquelético/embriologia , Músculo Esquelético/crescimento & desenvolvimento , Animais , ATPase de Ca(2+) e Mg(2+)/metabolismo , Diferenciação Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Embrião não Mamífero , Desenvolvimento Embrionário e Fetal , Comportamento Alimentar/fisiologia , Imuno-Histoquímica , Hibridização In Situ , Fatores de Transcrição MEF2 , Fibras Musculares de Contração Lenta/metabolismo , Músculo Esquelético/enzimologia , Proteína MyoD/genética , Proteína MyoD/metabolismo , Fatores de Regulação Miogênica , RNA Mensageiro/metabolismo , Succinato Desidrogenase/metabolismo , Natação/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
8.
Genes Dev ; 15(6): 652-7, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11274051

RESUMO

We have studied the flexed-tail (f) mouse to gain insight into mammalian mitochondrial iron metabolism. Flexed-tail animals have axial skeletal abnormalities and a transient embryonic and neonatal anemia characterized by pathologic intramitochondrial iron deposits in erythrocytes. Mitochondrial iron accumulation is the hallmark of sideroblastic anemias, which typically result from defects in heme biosynthesis or other pathways that lead to abnormal erythroid mitochondrial iron utilization. To clone the f gene, we used positional cloning techniques, and identified a frameshift mutation in a mitochondrial transmembrane protein. The mutated gene, Sfxn1, is the prototype of a novel family of evolutionarily conserved proteins present in eukaryotes.


Assuntos
Osso e Ossos/anormalidades , Proteínas de Transporte de Cátions , Membrana Celular/metabolismo , Proteínas de Membrana/genética , Mitocôndrias/metabolismo , Sequência de Aminoácidos , Animais , Northern Blotting , Western Blotting , Linhagem Celular , Clonagem Molecular , Análise Mutacional de DNA , DNA Complementar/metabolismo , Mutação da Fase de Leitura , Humanos , Proteínas de Membrana/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Modelos Genéticos , Dados de Sequência Molecular , Fases de Leitura Aberta , Fenótipo , Mapeamento Físico do Cromossomo , Homologia de Sequência de Aminoácidos , Distribuição Tecidual
9.
Clin Infect Dis ; 30(3): 540-4, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10722441

RESUMO

To compare intravenous (iv) ceftriaxone and penicillin G as therapy for neurosyphilis, blood and CSF were collected before and 14-26 weeks after therapy from 30 subjects infected with human immunodeficiency virus (HIV)-1 who had (1) rapid plasma reagin (RPR) test titers >/=1&rcolon;16, (2) reactive serum treponemal tests, and (3) either reactive CSF-Venereal Disease Research Laboratory (VDRL) tests or CSF abnormalities: (a) CSF WBC values >/=20/microL or (b) CSF protein values >/=50 mg/dL. At baseline, more ceftriaxone recipients had skin symptoms and signs (6 [43%] of 14 vs. 1 [6%] of 16; P=.03), and more penicillin recipients had a history of neurosyphilis (7 [44%] of 16 vs. 1 [7%] of 14; P=.04). There was no difference in the proportion of subjects in each group whose CSF measures improved. Significantly more ceftriaxone recipients had a decline in serum RPR titers (8 [80%] of 10 vs. 2 [13%] of 15; P=. 003), even after controlling for baseline RPR titer, skin symptoms and signs, or prior neurosyphilis were controlled for. Differences in the 2 groups limit comparisons between them. However, iv ceftriaxone may be an alternative to penicillin for treatment of HIV-infected patients with neurosyphilis and concomitant early syphilis.


Assuntos
Ceftriaxona/uso terapêutico , Cefalosporinas/uso terapêutico , Infecções por HIV/complicações , Neurossífilis/tratamento farmacológico , Penicilina G/uso terapêutico , Penicilinas/uso terapêutico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurossífilis/microbiologia , Projetos Piloto
10.
Anat Embryol (Berl) ; 197(6): 485-96, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9682979

RESUMO

The debate about the pattern of muscle formation in teleost fish has recently been heightened in the literature. Here we examine superficial muscle development in the pearlfish, a cyprinid endemic to a small area of Central Europe, and uninfluenced by economic interest and breeding. Using light and electron microscopy, histochemistry and immunohistochemistry techniques, we report that: (1) Superficial fibre precursors originate close to the notochord, are part of the same cell population as the so-called muscle pioneer cells, and are transferred laterally to end up at the surface of the myotome. (2) Superficial fibre maturation is exceptionally rapid. Structural and enzymatic functionality is attained at a time when prospective deep fibres have not passed beyond the early myotube state. This strong contrast weakens as the embryo develops. (3) Apart from the muscle pioneers, the superficial fibres appear to be capable of functioning before they receive any direct innervation, implying that signals are transferred to these fibres via cell-to-cell junctions. We suggest that the capability of rapid superficial fibre maturation is a rather general feature among teleosts and may aid pre-hatch survival under a variable environment. Our results indicate that muscle formation in teleost fish may follow a common basic pattern that is open to considerable ontogenetic and phylogenetic modification in response to habitat conditions.


Assuntos
Peixes/embriologia , Fibras Musculares de Contração Lenta/citologia , Animais , Peixes/anatomia & histologia , Peixes/crescimento & desenvolvimento , Imuno-Histoquímica , Microscopia Eletrônica , Fibras Musculares de Contração Lenta/ultraestrutura
11.
J Mol Evol ; 44(3): 327-35, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9060399

RESUMO

Based on sequence analyses of 17 complete centromeric DNA monomers from ten different deer species, a model is proposed for the genesis, evolution, and genomic organization of cervid satellite I DNA. All cervid satellite I DNA arose from the initial amplification of a 31-bp DNA sequence. These 31-bp subrepeats were organized in a hierarchical fashion as 0.8-kb monomers in plesiometacarpalia deer and 1-kb monomers in telemetacarpalia deer. The higher-order repeat nature of cervid centromeric satellite DNA monomers accounts for their high intragenomic and intraspecific sequence conservation. Such high intraspecific sequence conservation validates the use of a single cervid satellite I DNA monomer from each deer species for interspecific sequence comparisons to elucidate phylogenetic relationships. Also, a specific 0.18-kb tandem duplication was observed in all 1-kb monomers, implying that 1-kb cervid satellite I DNA monomers arose from an unequal crossover event between two similar 0.8-kb ancestral DNA sequences.


Assuntos
DNA Satélite/genética , Cervos/genética , Sequências Repetitivas de Ácido Nucleico , Animais , Clonagem Molecular , Dados de Sequência Molecular , Especificidade da Espécie
12.
Trends Ecol Evol ; 9(12): 486-7, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21236928
13.
Trends Ecol Evol ; 5(7): 214-8, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21232358

RESUMO

The recent development of computerized Geographic Information Systems, particularly those based on 'vector models', has provided ecologists with a facility for dividing areas of heterogeneous habitat into clearly defined, biologically meaningful subunits. These units, or 'polygons', provide an alternative framework to the more traditional grid system for a variety of types of study.

14.
Oecologia ; 78(4): 433-442, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28312171

RESUMO

Adult syrphid flies feed primarily on pollen and nectar from flowers and may be regarded as suitable models for the investigation of resource partitioning in a plant/pollinator system. The present study examines the extent to which a small group of six species are selective in their diets and investigates the role of flower colour as a means by which such selectivity may occur. Flower feeding preferences were determined by pollen analyses of gut contents and an extensive flower sampling programme was under-taken to provide information on the relative abundances of the food resources available to the insects. Flower colours were defined by their reflectance spectra, and the inherent colour preferences of the flies were determined by field experiments in which natural flowers were simulated using painted plastic discs. The results reveal that some hoverfly species are highly selective in their pollen diets, while others have a more generalist approach to their foraging. The division of flower resources by the more selective species is shown to be dependent, at least partially, on the colours of the flowers. The findings are discussed in relation to the theories of Competition and Optimal Foraging and the 'mechanistic approach' to ecology. The use of learning models is suggested as an alternative means of investigating patterns of resource use in future research.

15.
Appl Opt ; 24(11): 1571-84, 1985 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-18223759

RESUMO

A wide-angle Michelson Doppler imaging interferometer (WAMDII) is described that is intended to measure upper atmospheric winds and temperatures from naturally occurring visible region emissions, using Spacelab as a platform. It is an achromatic field-widened instrument, with good thermal stability, that employs four quarterwave phase-stepped images to generate full images of velocity, temperature, and emission rate. For an apparent emission rate of 5 kR and binning into 85 x 105 pixels, the required exposure time is 1 sec. The concept and underlying principles are described, along with some fabrication details for the prototype instrument. The results of laboratory tests and field measurements using auroral emissions are described and discussed.

16.
J Phys E ; 6(1): 98-100, 1973 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-4682165
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