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1.
J Wound Care ; 26(11): 642-650, 2017 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-29131748

RESUMO

OBJECTIVE: Our aim was to assess the effectiveness of hydro-responsive wound dressing (HRWD) in debridement and wound bed preparation of a variety of acute and chronic wounds that presented with devitalised tissue needing removal so that healing may proceed. METHOD: This was a non-comparative evaluation of acute and chronic wounds that required debridement as part of their normal treatment regimen. Clinicians recorded wound changes including a subjective assessment level of devitalised tissue and wound bed preparation, presence of pain, wound status (e.g., wound size) and periwound skin condition. Data was also collected from clinicians and patients to provide information on clinical performance of the dressing. RESULTS: We recruited 100 patients with a variety of wound types into the study. Over 90% of the clinicians reported removal of devitalised tissue to enable a healing response in both chronic and acute wounds. Specifically, over the course of the evaluation period, levels of devitalised tissue (necrosis and slough) reduced from 85.5% to 26.3%, and this was accompanied by an increase in wound bed granulation from 12.0% to 33.7%. Correspondingly, there was a 40% reduction in wound area, hence a clinically relevant healing response was seen upon treatment with HRWD. It is also noteworthy that this patient population included a significant proportion of chronic wounds (51.4%) that showed no signs of wound progression within <4 weeks before study inclusion. Of these chronic wounds, 93% demonstrated wound progression upon treatment with HRWD. Despite reported pain levels being low pre- and post-dressing change, overall wound pain improved (reduced) in 48% of patients. Periwound skin condition showed a tendency towards improvement, and the fluid management capabilities of the HRWD was reported as good to excellent in the majority of cases. Wound infections were reduced by at least 60% over the evaluation period. A simple cost-effective analysis demonstrated significant savings using HRWD (£6.33) over current standard practice regimens of a four-step debridement process (£8.05), larval therapy (£306.39) and mechanical pad debridement (£11.46). CONCLUSION: HRWD was well tolerated and was demonstrated to be an efficient debridement tool providing rapid, effective and pain free debridement in a variety of wound types.


Assuntos
Autólise , Bandagens , Desbridamento/métodos , Ferimentos e Lesões/terapia , Idoso , Idoso de 80 Anos ou mais , Análise Custo-Benefício , Exsudatos e Transudatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reepitelização , Escócia , Resultado do Tratamento , Infecção dos Ferimentos/prevenção & controle
2.
Orig Life Evol Biosph ; 45(1-2): 41-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25862330

RESUMO

The HR 8799 system, with its four giant planets and two debris belts, has an architecture closely mirroring that of our Solar system where the inner, warm asteroid belt and outer, cool Edgeworth-Kuiper belt bracket the giant planets. As such, it is a valuable laboratory for examining exoplanetary dynamics and debris disk-exoplanet interactions. Whilst the outer debris belt of HR 8799 has been well resolved by previous observations, the spatial extent of the inner disk remains unknown. This leaves a significant question mark over both the location of the planetesimals responsible for producing the belt's visible dust and the physical properties of those grains. We have performed the most extensive simulations to date of the inner, unresolved debris belt around HR 8799, using UNSW Australia's Katana supercomputing facility to follow the dynamical evolution of a model inner disk comprising 300,298 particles for a period of 60 Ma. These simulations have enabled the characterisation of the extent and structure of the inner disk in detail, and will in future allow us to provide a first estimate of the small-body impact rate and water delivery prospects for possible (as-yet undetected) terrestrial planet (s) in the inner system.


Assuntos
Evolução Planetária , Planetas , Astros Celestes , Modelos Teóricos
3.
Phys Rev Lett ; 108(21): 215004, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-23003273

RESUMO

Ignition implosions on the National Ignition Facility [J. D. Lindl et al., Phys. Plasmas 11, 339 (2004)] are underway with the goal of compressing deuterium-tritium fuel to a sufficiently high areal density (ρR) to sustain a self-propagating burn wave required for fusion power gain greater than unity. These implosions are driven with a very carefully tailored sequence of four shock waves that must be timed to very high precision to keep the fuel entropy and adiabat low and ρR high. The first series of precision tuning experiments on the National Ignition Facility, which use optical diagnostics to directly measure the strength and timing of all four shocks inside a hohlraum-driven, cryogenic liquid-deuterium-filled capsule interior have now been performed. The results of these experiments are presented demonstrating a significant decrease in adiabat over previously untuned implosions. The impact of the improved shock timing is confirmed in related deuterium-tritium layered capsule implosions, which show the highest fuel compression (ρR~1.0 g/cm(2)) measured to date, exceeding the previous record [V. Goncharov et al., Phys. Rev. Lett. 104, 165001 (2010)] by more than a factor of 3. The experiments also clearly reveal an issue with the 4th shock velocity, which is observed to be 20% slower than predictions from numerical simulation.

4.
J Acoust Soc Am ; 129(1): 5-11, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21302982

RESUMO

This paper considers the higher-order scattered and transmitted wave fields that result when an acoustic wave from a point source impinges at an arbitrary angle on a rectangular aperture in a rigid, thick wall. In this analysis, it is assumed that free field conditions exist on both sides of the aperture. Although the full scattered and transmitted pressure fields contain both modal sum and modal coupling effects, the modal coupling effects of the higher-order modes are ignored such that an approximate analytical solution to the uncoupled analysis can be utilized. Experiments have been undertaken to measure the sound pressure levels in the transmitted field that result when sound from a point source impinges on the opposite side of a rectangular aperture. Measurements were made with the source located at the required position to drive a particular in-aperture higher-order mode. The source was also located at positions that did not directly excite any in-aperture higher-order mode at a cut-on frequency. These results indicate that the approximate analysis developed here gives accurate solutions whether or not any mode of the aperture is driven at cut-on. Thus, the method can be used for any relative location of a source from a rectangular aperture of any dimensions.


Assuntos
Acústica , Modelos Teóricos , Som , Acústica/instrumentação , Desenho de Equipamento , Movimento (Física) , Pressão , Espectrografia do Som , Fatores de Tempo , Transdutores
5.
Science ; 262(5142): 2020-3, 1993 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-17794968

RESUMO

Histological and ultrastructural evaluation of the ends of long bones of juvenile dinosaurs from the Upper Cretaceous Two Medicine Formation of Montana revealed the preservation of growth plates. Growth plates are discs of cartilage present near the ends of growing long bones that generate bone elongation. Comparison of the fossils with modern taxa demonstrated homology of the growth plate in birds and dinosaurs. The presence of an avian-type growth plate in dinosaurs adds a shared derived anatomical character corroborating inclusion of birds within the Dinosauria. Additionally, possession of a growth plate, which in birds is capable of producing rapid determinate long bone growth, implies that an avian developmental pattern may have been present in these dinosaurs.

6.
J Clin Invest ; 100(6): 1363-72, 1997 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9294101

RESUMO

Significant numbers of myocytes die by apoptosis during myocardial infarction. The molecular mechanism of this process, however, remains largely unexplored. To facilitate a molecular genetic analysis, we have developed a model of ischemia-induced cardiac myocyte apoptosis in the mouse. Surgical occlusion of the left coronary artery results in apoptosis, as indicated by the presence of nucleosome ladders and in situ DNA strand breaks. Apoptosis occurs mainly in cardiac myocytes, and is shown for the first time to be limited to hypoxic regions during acute infarction. Since hypoxia-induced apoptosis in other cell types is dependent on p53, and p53 is induced by hypoxia in cardiac myocytes, we investigated the necessity of p53 for myocyte apoptosis during myocardial infarction. Myocyte apoptosis occurs as readily, however, in the hearts of mice nullizygous for p53 as in wild-type littermates. These data demonstrate the existence of a p53-independent pathway that mediates myocyte apoptosis during myocardial infarction.


Assuntos
Apoptose , Genes p53/fisiologia , Infarto do Miocárdio/patologia , Miocárdio/patologia , Animais , Hipóxia Celular , DNA/análise , Genes p53/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores de Tempo
7.
Bone ; 40(4): 1152-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17223615

RESUMO

It is beyond question that Mesozoic dinosaurs, like Aves and Crocodylia, are archosaurs. However, within the archosaurian clade, the origin and distribution of some major features are less clear, particularly with respect to reproductive physiology. Medullary bone, a highly mineralized, bony reproductive tissue present in the endosteal cavities of all extant egg-laying birds thus far examined, has recently been reported in Tyrannosaurus rex. Its presence or absence in extant crocodilians, therefore, may shed light on the timing of its evolutionary appearance. If medullary bone is present in all three taxa, it arose before the three lineages diverged. However, if medullary bone arose after this divergence, it may be present in both extinct dinosaurs and birds, or in birds only. If present in extinct dinosaurs and birds, but not crocodilians, it would indicate that it arose in the common ancestor of this clade, thus adding support to the closer phylogenetic relationship of dinosaurs and birds relative to crocodilians. Thus, the question of whether the crocodilian Alligator mississippiensis forms medullary bone during the production of eggs has important evolutionary significance. Our examination of long bones from several alligators (two alligators with eggs in the oviducts, one that had produced eggs in the past but was not currently in reproductive phase, an immature female and an adult male) shows no differences on the endosteal surfaces of the long bones, and no evidence of medullary bone, supporting the hypothesis that medullary bone first evolved in the dinosaur-bird line, after the divergence of crocodilians from this lineage.


Assuntos
Jacarés e Crocodilos/crescimento & desenvolvimento , Jacarés e Crocodilos/fisiologia , Jacarés e Crocodilos/classificação , Animais , Evolução Biológica , Aves/classificação , Aves/crescimento & desenvolvimento , Aves/fisiologia , Desenvolvimento Ósseo , Calcificação Fisiológica , Dinossauros/classificação , Dinossauros/crescimento & desenvolvimento , Dinossauros/fisiologia , Casca de Ovo/crescimento & desenvolvimento , Casca de Ovo/fisiologia , Feminino , Fósseis , Masculino , Oogênese , Oviposição
8.
Mol Cell Biol ; 13(5): 2765-75, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8474440

RESUMO

To gain insight into the role of Myc family oncoproteins and their associated protein Max in vertebrate growth and development, we sought to identify homologs in the zebra fish (Brachydanio rerio). A combination of a polymerase chain reaction-based cloning strategy and low-stringency hybridization screening allowed for the isolation of zebra fish c-, N-, and L-myc and max genes; subsequent structural characterization showed a high degree of conservation in regions that encode motifs of known functional significance. On the functional level, zebra fish Max, like its mammalian counterpart, served to suppress the transformation activity of mouse c-Myc in rat embryo fibroblasts. In addition, the zebra fish c-myc gene proved capable of cooperating with an activated H-ras to effect the malignant transformation of mammalian cells, albeit with diminished potency compared with mouse c-myc. With respect to their roles in normal developing tissues, the differential temporal and spatial patterns of steady-state mRNA expression observed for each zebra fish myc family member suggest unique functions for L-myc in early embryogenesis, for N-myc in establishment and growth of early organ systems, and for c-myc in increasingly differentiated tissues. Furthermore, significant alterations in the steady-state expression of zebra fish myc family genes concomitant with relatively constant max expression support the emerging model of regulation of Myc function in cellular growth and differentiation.


Assuntos
Evolução Biológica , Proteínas de Ligação a DNA/genética , Genes myc , Família Multigênica , Oncogenes , Fatores de Transcrição , Vertebrados/genética , Peixe-Zebra/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Fatores de Transcrição de Zíper de Leucina Básica , Expressão Gênica , Hominidae/genética , Humanos , Camundongos/genética , Dados de Sequência Molecular , Fases de Leitura Aberta , Mapeamento por Restrição , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Truta/genética , Xenopus/genética , Proteínas de Peixe-Zebra
9.
Mol Cell Biol ; 13(4): 2456-68, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8455622

RESUMO

A polymerase chain reaction-based cloning strategy allowed for the isolation of two distinct Xenopus L-myc genes, as well as previously isolated xc- and xN-myc genes, thus demonstrating that these three well-defined members of the mammalian myc gene family are present in lower vertebrates as well. Comparison of the Xenopus and mammalian Myc families revealed a high degree of structural relatedness at the gene and protein levels; this homology was consistent with the ability of the xc-myc1 and xN-myc1 genes to function as oncogenes in primary mammalian cells. In contrast, the xL-myc1 gene was found to be incapable of transforming rat embryo fibroblast cells, and this inactivity may relate to localized but significant differences in its putative transactivation domain. Analysis of xc-, xN-, and xL-myc gene expression demonstrated that (i) all three genes were highly expressed during oogenesis and their transcripts accumulated as abundant maternal mRNAs, (ii) each gene exhibited a distinctive pattern of expression during embryogenesis and in adult tissues, and (iii) the xL-myc1 and xL-myc2 genes were coordinately expressed in the maternal and zygotic genomes. The markedly high expression of the Xenopus myc gene family in differentiated tissues, such as the central nervous system and kidney, contrasts sharply with the low levels observed in mammalian adult tissues. These differences may reflect unique functions of the Myc family proteins in processes specific to amphibians, such as tissue regeneration.


Assuntos
Genes myc , Proteínas Proto-Oncogênicas c-myc/fisiologia , Xenopus laevis/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Transformação Celular Neoplásica/genética , Células Cultivadas , Galinhas , DNA/genética , Feminino , Peixes , Expressão Gênica , Humanos , Técnicas In Vitro , Masculino , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/genética , Ratos , Mapeamento por Restrição , Alinhamento de Sequência , Relação Estrutura-Atividade , Xenopus laevis/embriologia
10.
Mol Cell Biol ; 16(4): 1794-804, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8657155

RESUMO

To determine the role of L-Myc in normal mammalian development and its functional relationship to other members of the Myc family, we determined the normal patterns of L-myc gene expression in the developing mouse by RNA in situ hybridization and assessed the phenotypic impact of L-Myc deficiency produced through standard gene targeting methodology. L-myc transcripts were detected in the developing kidney and lung as well as in both the proliferative and the differentiative zones of the brain and neural tube. Despite significant expression of L-myc in developing mouse tissue, homozygous null L-myc mice were found to be viable, reproductively competent, and represented in expected frequencies from heterozygous matings. A detailed histological survey of embryonic and adult tissues, characterization of an embryonic neuronal marker, and measurement of cellular proliferation in situ did not reveal any congenital abnormalities. The lack of an apparent phenotype associated with L-Myc deficiency indicates that L-Myc is dispensable for gross morphological development and argues against a unique role for L-Myc in early central nervous system development as had been previously suggested. Although overlapping expression patterns among myc family members raise the possibility of complementation of L-Myc deficiency by other Myc oncoproteins, compensatory changes in the levels of c- and/or N-myc transcripts were not detected in homozygous null L-myc mice.


Assuntos
Desenvolvimento Embrionário e Fetal/genética , Regulação da Expressão Gênica no Desenvolvimento , Genes myc , Animais , Mutação em Linhagem Germinativa , Camundongos , Especificidade de Órgãos , Distribuição Tecidual , Transcrição Gênica
11.
Mol Cell Biol ; 19(1): 353-63, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9858559

RESUMO

This study examines in vivo the role and functional interrelationships of components regulating exit from the G1 resting phase into the DNA synthetic (S) phase of the cell cycle. Our approach made use of several key experimental attributes of the developing mouse lens, namely its strong dependence on pRb in maintenance of the postmitotic state, the down-regulation of cyclins D and E and up-regulation of the p57(KIP2) inhibitor in the postmitotic lens fiber cell compartment, and the ability to target transgene expression to this compartment. These attributes provide an ideal in vivo context in which to examine the consequences of forced cyclin expression and/or of loss of p57(KIP2) inhibitor function in a cellular compartment that permits an accurate quantitation of cellular proliferation and apoptosis rates in situ. Here, we demonstrate that, despite substantial overlap in cyclin transgene expression levels, D-type and E cyclins exhibited clear functional differences in promoting entry into S phase. In general, forced expression of the D-type cyclins was more efficient than cyclin E in driving lens fiber cells into S phase. In the case of cyclins D1 and D2, ectopic proliferation required their enhanced nuclear localization through CDK4 coexpression. High nuclear levels of cyclin E and CDK2, while not sufficient to promote efficient exit from G1, did act synergistically with ectopic cyclin D/CDK4. The functional differences between D-type and E cyclins was most evident in the p57(KIP2)-deficient lens wherein cyclin D overexpression induced a rate of proliferation equivalent to that of the pRb null lens, while overexpression of cyclin E did not increase the rate of proliferation over that induced by the loss of p57(KIP2) function. These in vivo analyses provide strong biological support for the prevailing view that the antecedent actions of cyclin D/CDK4 act cooperatively with cyclin E/CDK2 and antagonistically with p57(KIP2) to regulate the G1/S transition in a cell type highly dependent upon pRb.


Assuntos
Quinases relacionadas a CDC2 e CDC28 , Ciclina D1/metabolismo , Ciclina E/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Inibidores Enzimáticos/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas , Animais , Apoptose , Transporte Biológico , Núcleo Celular/metabolismo , Cristalinas , Ciclina D1/genética , Ciclina D2 , Ciclina E/genética , Quinase 2 Dependente de Ciclina , Quinase 4 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p57 , Quinases Ciclina-Dependentes/genética , Ciclinas/genética , Feminino , Fase G1 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Serina-Treonina Quinases/genética , Fase S
12.
Ann Clin Biochem ; 43(Pt 4): 314-7, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16824284

RESUMO

The hook effect is a well-recognized problem that can occur in assays of most tumour markers, including alpha feto-protein (AFP). We present a case of hepatoblastoma in a baby. The diagnosis was delayed as a result of unrecognized 'hooking' of a very high AFP concentration in the automated immunoassay method used. The falsely low result obtained was considered normal for the patient's age and supported the diagnosis of benign haemangioendothelioma. Liaison between clinical and laboratory staff was critical in obtaining an accurate AFP result, proceeding to liver biopsy and establishing the definitive diagnosis of hepatoblastoma. While the reasons and solutions for hook effect have been well researched and published, we believe the presence of extremely high serum AFP concentration in some hepatoblastoma patients means that the hook effect remains a problem and can generate erroneously low AFP results despite assay reformulation by manufacturers. Therefore constant vigilance by laboratory staff is still needed.


Assuntos
Biomarcadores Tumorais , Química Clínica/métodos , Hepatoblastoma/diagnóstico , Neoplasias Hepáticas/diagnóstico , Neoplasias/diagnóstico , alfa-Fetoproteínas/biossíntese , Automação , Biópsia , Diagnóstico Diferencial , Feminino , Hepatoblastoma/metabolismo , Humanos , Imunoensaio , Lactente , Fígado/patologia , Neoplasias/metabolismo , alfa-Fetoproteínas/análise
13.
Equine Vet J ; 47(1): 96-100, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24528106

RESUMO

REASONS FOR PERFORMING STUDY: A change in management from pasture to stabling is a risk factor for equine colic. OBJECTIVES: To investigate the effect of a management change from pasture with no controlled exercise to stabling with light exercise on aspects of gastrointestinal function related to large colon impaction. The hypothesis was that drinking water intake, faecal output, faecal water content and large intestinal motility would be altered by a transition from a pastured to a stabled regime. STUDY DESIGN: Within-subject management intervention trial involving changes in feeding and exercise using noninvasive techniques. METHODS: Seven normal horses were evaluated in a within-subjects study design. Horses were monitored while at pasture 24 h/day, and for 14 days following a transition to a stabling regime with light controlled exercise. Drinking water intake, faecal output and faecal dry matter were measured. Motility of the caecum, sternal flexure and left colon (contractions/min) were measured twice daily by transcutaneous ultrasound. Mean values were pooled for the pastured regime and used as a reference for comparison with stabled data (Days 1-14 post stabling) for multilevel statistical analysis. RESULTS: Drinking water intake was significantly increased (mean ± s.d. pasture 2.4 ± 1.8 vs. stabled 6.4 ± 0.6 l/100 kg bwt/day), total faecal output was significantly decreased (pasture 4.62 ± 1.69 vs. stabled 1.81 ± 0.5 kg/100 kg bwt/day) and faecal dry matter content was significantly increased (pasture 18.7 ± 2.28 vs. stabled 27.2 ± 1.93% DM/day) on all days post stabling compared with measurements taken at pasture (P<0.05). Motility was significantly decreased in all regions of the large colon collectively on Day 2 post stabling (-0.76 contractions/min), and in the left colon only on Day 4 (-0.62 contractions/min; P<0.05). CONCLUSIONS: There were significant changes in large intestinal motility patterns and parameters relating to gastrointestinal water balance during a transition from pasture to stabled management, particularly during the first 5 days.


Assuntos
Ingestão de Líquidos/fisiologia , Motilidade Gastrointestinal/fisiologia , Cavalos/fisiologia , Abrigo para Animais , Condicionamento Físico Animal/fisiologia , Animais , Fezes , Feminino , Masculino
14.
J Clin Endocrinol Metab ; 48(6): 959-63, 1979 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-447802

RESUMO

The GH dependency of somatomedin (SM) peptide content in plasma was assessed using the placental membrane radioreceptor assay (RRA) to measure whole and acid-chromatographed plasma using both [125I]SM A and [125I]SM C. Plasmas from 10 normal children and adults, 11 GH-deficient children before and after therapy with 0.1 U/kg GH im daily for 5 days, and 10 acromegalic patients were assayed as well as a standard plasma pool from 20 healthy adult males. The results of these assays revealed that the SM content of plasma is GH dependent and that assay of whole and acid-chromatographed plasma with the [125I]SM A RRA and assay of acid-chromatographed plasma with the [125I]SM C RRA give comparable measurements of SM peptide content. There was a positive correlation of the [125I]SM A RRAs of whole and acid-chromatographed plasma from each patient (r = 0.87; n = 41; P much less than 0.001). An even stronger positive correlation was observed when the [125I]SM A and [125I]SM C RRAs of acid-chromatographed plasma were compared (r = 0.94; n = 41; P much less than 0.001). Furthermore, it was demonstrated that precise measurement of SM peptide content in plasmas from subjects with abnormal GH states and from normal subjects is enhanced by acid chromatography of the plasma before assay in either the [125I]SM A or [125I]SM C RRA.


Assuntos
Hormônio do Crescimento/deficiência , Somatomedinas/líquido cefalorraquidiano , Acromegalia/sangue , Acromegalia/tratamento farmacológico , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Hormônio do Crescimento/uso terapêutico , Humanos , Hipopituitarismo/sangue , Hipopituitarismo/tratamento farmacológico , Pessoa de Meia-Idade , Ensaio Radioligante
15.
J Clin Endocrinol Metab ; 47(6): 1287-95, 1978 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-263658

RESUMO

The placental membrane radioreceptor assay was used to measure the levels of somatomedin (SM) peptides in plasma. Displacement of both [125I]somatomedin A ([125I]SM-A) and [125I]somatomedin C ([125I]SM-C) by normal whole plasma, the peptide fraction of acid-chromatographed plasma, and a partially purified, insulin-free SM preparation were compared. The peptide fraction of plasma was isolated by acid chromatography over Sephadex G-50 in 0.25 M formic acid with a yield of greater than or equal to 90%, as determined by bioassay and [125I]SM. In the case of [125I]SM-A, the dose-response curves for whole plasma, acid-chromatographed plasma, and the standard SM preparation were parallel (P less than 0.2). In contrast, for [125I]SM-C, the dose-response curves for acid-chromatographed plasma and the purified SM preparation were parallel (P less than 0.2), but both differed significantly from that of whole plasma (P less than 0.001). In addition, there was less variability in the assay of acid-chromatographed plasma compared to whole plasma. The results indicate that radioreceptor assay of unextracted normal plasma using [125I]SM-A is a valid measure of SM peptide concentration, while radioreceptor assay of unextracted normal plasma using [125I]SM-C, in our hands, is not. Acid chromatography of plasma before its assay is an uncomplicated procedure which allows valid and precise measurement of SM peptide content using either [125I]SM-A or [125I]SM-C.


Assuntos
Cromatografia em Gel , Formiatos , Fator de Crescimento Insulin-Like II , Somatomedinas , Somatomedinas/sangue , Adulto , Humanos , Fator de Crescimento Insulin-Like I , Radioisótopos do Iodo , Masculino , Placenta , Ensaio Radioligante , Somatomedinas/isolamento & purificação
16.
J Clin Endocrinol Metab ; 53(6): 1148-53, 1981 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7298798

RESUMO

In order to study the interrelationship of GH, somatomedin (SM), and growth in insulin-dependent diabetes mellitus (IDDM), concentrations of serum glucose, serum GH, and plasma SM were determined at 2-h intervals for 48 h in 19 ambulatory children with IDDM of at least 2-yr duration (mean duration, 6 yr) and in 9 normal age-matched controls. Serum glucose was significantly elevated (P less than 0.001) in subjects with IDDM compared to controls [287 +/- 15 mg/dl vs. 99 +/- 2 mg/dl (mean +/- SEM)] as was the hemoglobin A1C (11.0 +/- 0.40% vs. 4.59 +/- 0.08%) and the serum GH (8.4 +/- 0.4 ng/ml vs. 5.6 +/- 0.6 ng/ml; P less than 0.002). Despite evidence of inadequate diabetes control and elevated GH levels, the subjects with IDDM had normal SM levels (1.82 +/- 0.14 U/ml) compared to their age-matched controls (mean, 1.66 +/- 0.19 U/ml) and normal growth. Furthermore, SM levels did not show any significant diurnal variation in either group. There was no significant correlation in either group between the mean plasma SM concentrations and the mean serum GH or mean serum glucose concentration of each subject. These findings of normal SM levels and elevated GH levels in these children with normal stature and IDDM suggest a partial block in GH action.


Assuntos
Diabetes Mellitus Tipo 1/sangue , Hormônio do Crescimento/sangue , Somatomedinas/sangue , Adolescente , Glicemia/metabolismo , Criança , Ritmo Circadiano , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino
17.
Evolution ; 55(4): 773-82, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11392395

RESUMO

Host-associated mating is crucial in maintaining the partial reproductive isolation between the host races of Eurosta solidaginis (Diptera: Tephritidae), a fly that forms galls on Solidago altissima and S. gigantea. (We refer to flies reared from S. gigantea as gigantea flies and those reared from S. altissima as altissima flies.) We measured the host preference of males and females of both host races, F1 hybrids between the host races, F2, and backcrosses to both host races. Male and female altissima flies and female gigantea flies had high host fidelity, whereas male gigantea flies had low host fidelity. This result suggests that there may be gene flow between the host races due to nonassortative mating that occurs when male gigantea mate with altissima females on S. altissima. This indicates assortative-mating mechanisms in addition to host-associated mating are required to produce the partial reproductive isolation between the host races that has been observed. Nongenetic factors had no influence on host preference. Larval conditioning did not influence host preference: reciprocal F1 hybrids reared in S. altissima and S. gigantea both preferred S. gigantea. Adult experience had no impact on host preference: females preferred their natal host plant regardless of which host they encountered first as an adult. The hypothesis that maternal effects influence preferences was rejected because male and female flies did not show a consistent preference for the host plant of their mother. We also found no evidence that preference was a sex-linked trait because F1 and backcrosses to the host races with different combinations of X chromosomes from the two host races preferred S. gigantea. Our results indicate that host preference is not determined by a large number of genes because preference of hybrids did not correspond to the proportion of the genome derived from each host race. The strength of the ovipuncture preference for S. gigantea by gigantea females, the females of both reciprocal F1 hybrids, the backcross to gigantea, and F2s indicates that preference is inherited nonadditively at a limited number of loci. The F1 female hybrids, however, had a weaker host preference for S. gigantea than the pure gigantea host race, indicating that there may be incomplete dominance or modifier loci. Males had different host preference patterns than females, with individual male gigantea and male F1 hybrids usually exhibiting preference exclusively for S. gigantea or S. altissima. One hypothesis explaining the difference in host preference between males and females is that the same gene influences both female and male host preference, but it is a sex-influenced gene. Thus, males carrying the gene for S. gigantea preference have an intermediate host preference, whereas females have a strong host preference to S. gigantea. In summary, we found that the host preference that produces host-associated mating is inherited nonadditively at a relatively small number of loci on autosomal genes. This mode of inheritance meets the assumptions of models of sympatric speciation, indicating that the host races could have evolved in sympatry.


Assuntos
Evolução Biológica , Dípteros/genética , Interações Hospedeiro-Parasita/genética , Plantas/parasitologia , Animais , Cruzamentos Genéticos , Dípteros/fisiologia , Feminino , Masculino , Oviposição/genética , Oviposição/fisiologia
18.
Arch Neurol ; 45(7): 760-3, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3390031

RESUMO

Impairment of writing ability was studied in 20 patients with mild to moderate dementia caused by early-onset Alzheimer's disease. A multicomponent analysis was made of a brief narrative writing sample obtained from each patient, and this writing proficiency score was compared with results of standard tests of cognitive function as well as ratings of the degree of dementia. In these patients, significant correlations were observed between this brief test of narrative writing ability and the severity of dementia. An analysis of writing proficiency appears to be a simple means of assessing the severity of dementia caused by Alzheimer's disease. Further studies are needed to show the potential usefulness of such measures of agraphia in subtyping this disease.


Assuntos
Agrafia/complicações , Doença de Alzheimer/complicações , Idoso , Agrafia/psicologia , Doença de Alzheimer/psicologia , Feminino , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Redação
19.
Arch Neurol ; 48(11): 1170-3, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1953404

RESUMO

We studied 23 individuals (16 men, seven women; mean age 57 years) who had brainstem strokes confirmed by computed tomography of the head or magnetic resonance imaging. Videofluoroscopic modified barium-swallowing examination showed aspiration in 15 of 23 patients. Of the 15 aspirating patients, the majority had bilateral strokes with multiple lesion loci, most often in association with large-vessel disease. All 15 patients had involvement of the pons or medulla. Statistical analyses revealed a significant association between aspiration and pharyngeal residue observed under videofluoroscopy, cranial nerve IX abnormality, vocal fold weakness, and severe dysarthria. Despite initial severity, recovery was good. Following an aggressive program of aspiration prevention, over 80% of patients resumed full oral nutrition at the last follow-up.


Assuntos
Tronco Encefálico , Transtornos Cerebrovasculares/complicações , Transtornos de Deglutição/etiologia , Adulto , Idoso , Tronco Encefálico/patologia , Transtornos Cerebrovasculares/patologia , Nervos Cranianos/fisiopatologia , Transtornos de Deglutição/terapia , Disartria/etiologia , Feminino , Humanos , Inalação , Masculino , Pessoa de Meia-Idade , Sistema Nervoso/fisiopatologia , Faringe/fisiopatologia , Prega Vocal/fisiopatologia
20.
Neurology ; 38(2): 317-9, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3340301

RESUMO

Neurogenic dysphagia following stroke is not limited to brainstem involvement. Among 21 patients with stroke, one-third demonstrated only unilateral signs. In eight patients with silent aspiration, less subjective complaints, weaker cough, and dysphonia occurred more often. Videofluoroscopy must be used liberally in unilateral and bilateral strokes.


Assuntos
Transtornos Cerebrovasculares/complicações , Transtornos de Deglutição/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos Cerebrovasculares/fisiopatologia , Feminino , Fluoroscopia , Humanos , Inalação , Masculino , Pessoa de Meia-Idade , Gravação de Videoteipe
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