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1.
Child Dev ; 93(3): 815-830, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34897651

RESUMO

Working memory training improves children's cognitive performance on untrained tasks; however, little is known about the underlying neural mechanisms. This was investigated in 32 typically developing children aged 10-14 years (19 girls and 13 boys) using a randomized controlled design and multi-modal magnetic resonance imaging (Devon, UK; 2015-2016). Training improved working memory performance and increased intrinsic functional connectivity between the bilateral intraparietal sulci. Furthermore, improvements in working memory were associated with greater recruitment of the left middle frontal gyrus on a complex span task. Repeated engagement of fronto-parietal regions during training may increase their activity and functional connectivity over time, affording greater working memory performance. The plausibility of generalizable cognitive benefits from a neurobiological perspective and implications for neurodevelopmental theory are discussed.


Assuntos
Aprendizagem , Memória de Curto Prazo , Mapeamento Encefálico , Criança , Feminino , Lobo Frontal/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Lobo Parietal/diagnóstico por imagem
2.
Nat Genet ; 1(5): 379-84, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1338772

RESUMO

Genetic disorders affecting the central nervous system (CNS) can potentially be treated by gene transfer using vectors which infect and express genes in post-mitotic neurons. Herpesviruses establish latent infections in neurons during which only one viral gene (LAT) is expressed, thus the LAT promoter may express foreign genes in latently infected CNS cells. Expression of a beta-glucuronidase gene driven by the LAT promoter was tested in mice lacking this enzyme, which are a model for a human genetic disease affecting the CNS (mucopolysaccharidosis VII, Sly disease). Cells expressing the missing enzymatic activity were present in the trigeminal ganglia and brainstems of latently infected animals, up to four months post-inoculation, demonstrating the potential of this approach for the long-term expression of foreign genes in the CNS.


Assuntos
Tronco Encefálico/metabolismo , Genes Virais , Glucuronidase/genética , Glucuronidase/metabolismo , Simplexvirus/genética , Transfecção/métodos , Gânglio Trigeminal/metabolismo , Animais , Vetores Genéticos , Hibridização In Situ , Camundongos , Camundongos Endogâmicos , Neurônios/metabolismo , Regiões Promotoras Genéticas , Proteínas Recombinantes de Fusão/metabolismo , Mapeamento por Restrição
3.
Infect Dis Health ; 28(3): 151-158, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36803829

RESUMO

BACKGROUND: Vancomycin resistant enterococci (VRE) have become endemic pathogens in many Australian hospitals causing significant morbidity. There are few observational studies that have evaluated the effect of antibiotic usage on VRE acquisition. This study examined VRE acquisition and its association with antimicrobial use. The setting was a NSW tertiary hospital with 800 beds over a 63 month period up to March 2020, straddling piperacillin-tazobactam (PT) shortages that occurred from in September 2017. METHODS: The primary outcome was monthly inpatient hospital onset Vancomycin-resistant Enterococci (VRE) acquisitions. Multivariate adaptive regression splines (MARS) were used to estimate hypothetical thresholds, where antimicrobial use above threshold is associated with increased incidence of hospital onset VRE acquisition. Specific antimicrobials and categorised usage (broad, less broad and narrow spectrum) were modelled. RESULTS: There were 846 hospital onset VRE detections over the study period. Hospital onset vanB and vanA VRE acquisitions fell significantly by 64% and 36% respectively after the PT shortage. MARS modelling indicated that PT usage was the only antibiotic found to exhibit a meaningful threshold. PT usage greater than 17.4 defined daily doses/1000 occupied bed-days (95%C I: 13.4, 20.5) was associated with higher onset of hospital VRE. CONCLUSIONS: This paper highlights the large, sustained impact that reduced broad spectrum antimicrobial use had on VRE acquisition and showed that PT use in particular was a major driver with a relatively low threshold. It raises the question as to whether hospitals should be determining local antimicrobial usage targets based on direct evidence from local data analysed with non-linear methods.


Assuntos
Anti-Infecciosos , Enterococos Resistentes à Vancomicina , Humanos , Fatores de Tempo , Austrália , Antibacterianos/uso terapêutico , Centros de Atenção Terciária , Combinação Piperacilina e Tazobactam
4.
Nat Commun ; 14(1): 1387, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36914650

RESUMO

The affinities of extinct organisms are often difficult to resolve using morphological data alone. Chemical analysis of carbonaceous specimens can complement traditional approaches, but the search for taxon-specific signals in ancient, thermally altered organic matter is challenging and controversial, partly because suitable positive controls are lacking. Here, we show that non-destructive Fourier Transform Infrared Spectroscopy (FTIR) resolves in-situ molecular fingerprints in the famous 407 Ma Rhynie chert fossil assemblage of Aberdeenshire, Scotland, an important early terrestrial Lagerstätte. Remarkably, unsupervised clustering methods (principal components analysis and K-mean) separate the fossil spectra naturally into eukaryotes and prokaryotes (cyanobacteria). Additional multivariate statistics and machine-learning approaches also differentiate prokaryotes from eukaryotes, and discriminate eukaryotic tissue types, despite the overwhelming influence of silica. We find that these methods can clarify the affinities of morphologically ambiguous taxa; in the Rhynie chert for example, we show that the problematic "nematophytes" have a plant-like composition. Overall, we demonstrate that the famously exquisite preservation of cells, tissues and organisms in the Rhynie chert accompanies similarly impressive preservation of molecular information. These results provide a compelling positive control that validates the use of infrared spectroscopy to investigate the affinity of organic fossils in chert.


Assuntos
Ecossistema , Fósseis , Plantas , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Nature ; 442(7098): 82-5, 2006 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-16738545

RESUMO

MicroRNAs (miRNAs) are a class of small RNA molecules that regulate the stability or the translational efficiency of target messenger RNAs (mRNAs). The latency-associated transcript (LAT) of herpes simplex virus-1 (HSV-1) is the only viral gene expressed during latent infection in neurons. LAT inhibits apoptosis and maintains latency by promoting the survival of infected neurons. No protein product has been attributed to the LAT gene and the mechanism by which LAT protects cells from apoptosis is not yet known. Here we show that a miRNA encoded by the HSV-1 LAT gene confers resistance to apoptosis. Neuroblastoma cells transfected with a fragment of the LAT gene show reduced susceptibility to cell death. The anti-apoptotic function of LAT has been mapped to a region within the first exon. We have identified and characterized a microRNA (miR-LAT) generated from the exon 1 region of the HSV-1 LAT gene. The LAT miRNA was found to accumulate in cells transiently transfected with the LAT gene fragment or infected with a wild-type strain of HSV-1. A mutant virus in which a 372-nucleotide fragment encompassing the mature miRNA was deleted neither protected the infected cells from apoptosis nor generated an miRNA. miR-LAT exerts its anti-apoptotic effect by downregulation of transforming growth factor (TGF)-beta 1 and SMAD3 expression, both of which are functionally linked in the TGF-beta pathway. Our results suggest that the miRNA encoded by the HSV-1 LAT gene regulates the induction of apoptosis in infected cells by modulation of TGF-beta signalling and thus contributes to the persistence of HSV in a latent form in sensory neurons.


Assuntos
Apoptose , Herpesvirus Humano 1/genética , MicroRNAs/genética , Neurônios/citologia , Neurônios/virologia , RNA Viral/genética , Proteínas Virais/genética , Sequência de Bases , Linhagem Celular , Herpesvirus Humano 1/fisiologia , Humanos , MicroRNAs/metabolismo , Dados de Sequência Molecular , RNA Viral/metabolismo , Ribonuclease III/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia
6.
Bone ; 152: 116068, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34166859

RESUMO

Circulating microRNAs (c-miRs) show promise as biomarkers. This systematic review explores their potential association with age-related fracture/osteoporosis (OP), osteoarthritis (OA) and sarcopenia (SP), as well as cross-disease association. Most overlap occurred between OA and OP, suggesting potentially shared microRNA activity. There was little agreement in results across studies. Few reported receiver operating characteristic analysis (ROC) and many identified significant dysregulation in disease, but direction of effect was commonly conflicting. c-miRs with most evidence for consistency in dysregulation included miR-146a, miR-155 and miR-98 for OA (upregulated). Area under the curve (AUC) for miR-146a biomarker performance was AUC 0.92, p = 0.028. miR-125b (AUC 0.76-0.89), miR-100, miR-148a and miR-24 were consistently upregulated in OP. Insufficient evidence exists for c-miRs in SP. Study quality was typically rated intermediate/high risk of bias. Wide study heterogeneity meant meta-analysis was not possible. We provide detailed critique and recommendations for future approaches in c-miR analyses based on this review.


Assuntos
MicroRNA Circulante , MicroRNAs , Osteoartrite , Osteoporose , Sarcopenia , Biomarcadores , Humanos , MicroRNAs/genética , Osteoartrite/genética , Osteoporose/genética , Curva ROC , Sarcopenia/genética
7.
Nat Commun ; 12(1): 3002, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34031423

RESUMO

Changes in the Atlantic Meridional Overturning Circulation, which have the potential to drive societally-important climate impacts, have traditionally been linked to the strength of deep water formation in the subpolar North Atlantic. Yet there is neither clear observational evidence nor agreement among models about how changes in deep water formation influence overturning. Here, we use data from a trans-basin mooring array (OSNAP-Overturning in the Subpolar North Atlantic Program) to show that winter convection during 2014-2018 in the interior basin had minimal impact on density changes in the deep western boundary currents in the subpolar basins. Contrary to previous modeling studies, we find no discernable relationship between western boundary changes and subpolar overturning variability over the observational time scales. Our results require a reconsideration of the notion of deep western boundary changes representing overturning characteristics, with implications for constraining the source of overturning variability within and downstream of the subpolar region.

8.
Age Ageing ; 39(2): 234-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20032523

RESUMO

BACKGROUND: the presence of osteoporosis in patients with hip and knee osteoarthritis (OA) has important implications for understanding disease progression and providing optimal surgical and medical management. OBJECTIVE: to determine the prevalence of osteoporosis among patients with osteoarthritis awaiting total knee arthroplasty or total hip arthroplasty aged between 65 and 80 years. DESIGN: cross-sectional observational study. SETTING: tertiary referral centre in Newcastle upon Tyne, UK. SUBJECTS: patients with osteoarthritis awaiting total knee hip arthroplasty aged between 65 and 80 years. METHODS: lumbar spine, bilateral femoral and forearm bone mineral density (BMD) measurements were obtained using dual-energy X-ray absorptiometry. RESULTS: the cohort consisted of 199 patients with a mean age of 72 years (SD 4), and 113 (57%) were women. The overall rate of osteoporosis at any site was 23% (46/199) and a further 43% (85/199) of patients would have been classified as osteopaenic according to World Health Organization criteria. Osteoporosis was more commonly detected in the forearm (14%) than the lumbar spine (8.5%) and proximal femur of the index side (8.2%). CONCLUSIONS: in summary, a significant proportion of patients with end-stage OA have osteoporosis but this diagnosis may be missed unless BMD measurements are performed at sites distant from joints affected by OA.


Assuntos
Densidade Óssea/fisiologia , Osteoartrite do Quadril/complicações , Osteoartrite do Joelho/complicações , Osteoporose/epidemiologia , Absorciometria de Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Fêmur/fisiologia , Antebraço/fisiologia , Humanos , Modelos Logísticos , Masculino , Osteoartrite do Quadril/diagnóstico por imagem , Osteoartrite do Joelho/diagnóstico por imagem , Osteoporose/complicações , Prevalência , Fatores Sexuais , Coluna Vertebral/fisiologia , Inquéritos e Questionários , Reino Unido/epidemiologia
9.
Gene Ther ; 16(7): 927-32, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19458648

RESUMO

The neurogenetic, lysosomal enzyme (LSE) deficiency diseases are characterized by storage lesions throughout the brain; therefore, gene transfer needs to provide widespread distribution of the normal enzyme. Adeno-associated virus (AAV) vectors can be effective in the brain despite limited transduction because LSEs are exported to neighboring cells (cross-correction) to reverse the metabolic deficit. The extent of correction is determined by a combination of the total amount of LSE produced by a vector and the spatial distribution of the vector within the brain. Neuron-specific promoters have been used in the brain because AAV predominantly transduces neurons. However, these promoters are large, using up a substantial amount of the limited cloning capacity of AAV vector genomes. A small promoter that is active in all cells, from the LSE beta-glucuronidase (GUSB), has been used for long-term expression in AAV vectors in the brain but the natural promoter is expressed at very low levels. The amount of LSE exported from a cell is proportional to the level of transcription, thus more active promoters would export more LSE for cross-correction, but direct comparisons have not been reported. In this study, we show that in long-term experiments (>6 months) the GUSB minimal promoter (hGBp) expresses the hGUSB enzyme in brain at similar levels as the neuron-specific enolase promoter or the promoter from the latency-associated transcript of herpes simplex virus. The hGBp minimal promoter thus may be useful for long-term expression in the central nervous system of large cDNAs, bicitronic transcription units, self-complimentary or other designs with size constraints in the AAV vector system.


Assuntos
Encéfalo/enzimologia , Dependovirus/genética , Vetores Genéticos/uso terapêutico , Glucuronidase/metabolismo , Lisossomos/enzimologia , Regiões Promotoras Genéticas , Animais , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Glucuronidase/biossíntese , Glucuronidase/genética , Humanos , Injeções , Lisossomos/patologia , Camundongos , Mucopolissacaridose VII/enzimologia , Mucopolissacaridose VII/terapia , Distribuição Tecidual , Transcrição Gênica/genética , Transdução Genética/métodos
11.
Ann R Coll Surg Engl ; 101(6): 411-414, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31155886

RESUMO

INTRODUCTION: This single centre study retrospectively analysed the intraoperative findings relative to source of referral for emergency scrotal explorations performed in a tertiary level paediatric surgery department. METHODS: All patients who underwent emergency scrotal exploration under the care of paediatric surgeons in our unit between April 2008 and April 2016 were identified. Clinical data were obtained from contemporaneous records. RESULTS: Over the 8-year study period, 662 boys underwent emergency scrotal exploration: 6 (1%) were internal referrals, 294 (44%) attended our emergency department (ED) directly, 271 (41%) were referred from primary care and 91 (14%) were transferred from other hospitals. Excluding procedures in neonates, testicular torsion was present in 100 cases (15%). Testicular detorsion with bilateral 3-point testicular fixation was performed in 66 (66%) and orchidectomy with contralateral fixation in 34 (34%) where the torted testis was non-viable intraoperatively. The orchidectomy rate in the presence of torsion was 23% in ED referrals (12/52), 43% in primary care referrals (12/28) and 50% for transfers (10/20). The difference in rates between ED referrals and patients transferred from other hospitals was significant (p=0.026). There was no significant difference in median age between any of the groups (p=0.10). CONCLUSIONS: Boys undergoing emergency scrotal exploration had a higher orchidectomy rate when transferred from other hospitals to our unit. This difference was statistically significant when compared with boys presenting directly to our ED. This supports advice from The Royal College of Surgeons of England for undertaking paediatric scrotal explorations in the presenting hospital when safe to do so rather than delaying the care of these patients by transferring them to a tertiary paediatric surgical unit.


Assuntos
Encaminhamento e Consulta/estatística & dados numéricos , Torção do Cordão Espermático/terapia , Adolescente , Fatores Etários , Criança , Pré-Escolar , Serviços Médicos de Emergência/estatística & dados numéricos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino , Orquiectomia/estatística & dados numéricos , Atenção Primária à Saúde/estatística & dados numéricos , Estudos Retrospectivos , Torção do Cordão Espermático/diagnóstico , Testículo/cirurgia , Resultado do Tratamento
12.
Aust Vet J ; 95(12): 480-482, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29243240

RESUMO

OBJECTIVE: To determine the baseline pH and temperature of the preputial cavity of bulls. METHODS: We enrolled 55 bulls ranging in age from 15 to 84 months. The preputial temperature and pH were measured by insertion of temperature and pH probes, respectively, into the preputial orifice prior to routine breeding soundness examinations. Information was obtained from owners regarding the diet of each bull and categorised as one of three categories: forage only, grain supplemented or silage supplemented. RESULTS: The average temperature of the prepuce was 37.81°C ± 1.76 and the median pH of the prepuce was 8.45 (6.35-9.46). Preputial temperatures of the bull weakly correlated with ambient temperatures (rs = -0.29, P = 0.028). The preputial pH of silage-fed bulls was significantly lower than that of bulls fed forage only (P = 0.025) or grain-supplemented diets (P = 0.002). The median preputial pH of bulls fed a silage-based diet was 7.6 (6.3-8.9) compared with a median pH 8.7 (7.8-9.1) for bulls fed forage-based diets or a median of 8.5 (7.7-9.4) for those given grain-supplemented diets. CONCLUSION: Diet and ambient temperature can, respectively, affect pH and the temperature in the prepuce. Further studies to describe and understand the microbiota of the prepuce and penis may assist in developing treatments for diseases of the genital tract in bulls.


Assuntos
Bovinos/fisiologia , Pênis/fisiologia , Ração Animal , Animais , Temperatura Corporal/fisiologia , Dieta/métodos , Dieta/veterinária , Concentração de Íons de Hidrogênio , Masculino
14.
Cancer Res ; 60(20): 5714-22, 2000 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11059765

RESUMO

Neuro-attenuated herpes simplex virus-1 (HSV-1) gamma34.5 mutants can slow progression of preformed tumors and lead to complete regression of some tumors. However, the role of the immune response in this process is poorly understood. Syngenic DBA/2 tumor-bearing mice treated with HSV-1 1716 fourteen days after tumor implantation had significant prolongation in survival when compared with mice treated with viral growth sera (mock; 38.9 +/- 2.3 versus 24.9 +/- 0.6, respectively; P < 0.0001). Additionally, 60% of the animals treated on day 7 had complete regression of the tumors. However, no difference was observed in the mean survival rates of viral- or mock-treated tumor-bearing SCID mice (15 +/- 1.7 versus 14.8 +/- 2.2, respectively). When DBA/2 mice syngenic for the tumor were depleted of leukocytes by cyclophosphamide administration (before and during viral administration), there was again no significant difference observed in the survival times (19.0 +/- 1.9 versus 19.5 +/- 2.7, respectively). These data demonstrate that the immune response contributes to the viral-mediated tumor destruction and the increase in survival. Immune cell infiltration was up-regulated, specifically CD4+ T cells and macrophages (which are found early after viral administration). Prior immunity to HSV-1 increased survival times of treated mice over those of naive mice, an important consideration because 50-95% of the adult human population is sero-positive for HSV-1. Our results imply that the timing of viral administration and the immune status of the animals will be an important consideration in determining the effectiveness of viral therapies.


Assuntos
Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/terapia , Herpesvirus Humano 1/fisiologia , Melanoma Experimental/imunologia , Melanoma Experimental/terapia , Animais , Apoptose/fisiologia , Neoplasias Encefálicas/virologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/imunologia , Feminino , Vacinas contra o Vírus do Herpes Simples/administração & dosagem , Vacinas contra o Vírus do Herpes Simples/imunologia , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/imunologia , Injeções Intraventriculares , Células Matadoras Naturais/imunologia , Macrófagos/imunologia , Melanoma Experimental/virologia , Camundongos , Camundongos Endogâmicos DBA , Camundongos SCID , Transplante de Neoplasias , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia
15.
Cancer Res ; 57(3): 466-71, 1997 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9012475

RESUMO

Modified, nonneurovirulent herpes simplex viruses (HSVs) have shown promise in the treatment of brain tumors. However, HSV-1 can infect and lyse a wide range of cell types. In this report, we show that HSV-1716, a mutant lacking both copies of the gene coding ICP-34.5, can effectively treat a localized i.p. malignancy. Human malignant mesothelioma cells supported the growth of HSV-1716 and were efficiently lysed in vitro. i.p. injection of HSV-1716 into animals with established tumor nodules reduced tumor burden and significantly prolonged survival in an animal model of non-central nervous system-localized human malignancy without dissemination or persistence after i.p. injection into SCID mice bearing human tumors. These findings suggest that this virus may be efficacious and safe for use in localized human malignancies of nonneuronal origin such as malignant mesothelioma.


Assuntos
Terapia Genética , Mesotelioma/terapia , Simplexvirus/genética , Proteínas Virais/genética , Replicação Viral , Animais , Humanos , Camundongos , Camundongos SCID , Mutação , Simplexvirus/fisiologia , Células Tumorais Cultivadas
17.
J Am Coll Cardiol ; 40(5): 961-6, 2002 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-12225723

RESUMO

OBJECTIVES: The aim of the present study was to assess the contribution of angiotensin-converting enzyme (ACE) inhibitor therapy to bradykinin-induced tissue-type plasminogen activator (t-PA) release in patients with heart failure (HF) secondary to ischemic heart disease. BACKGROUND: Bradykinin is a potent endothelial cell stimulant that causes vasodilatation and t-PA release. In large-scale clinical trials, ACE inhibitor therapy prevents ischemic events. METHODS: Nine patients with symptomatic HF were evaluated on two occasions: during and following seven-day withdrawal of long-term ACE inhibitor therapy. Forearm blood flow was measured using bilateral venous occlusion plethysmography. Intrabrachial bradykinin (30 to 300 pmol/min), substance P (2 to 8 pmol/min), and sodium nitroprusside (1 to 4 pmol/min) were infused, and venous blood samples were withdrawn from both forearms for estimation of fibrinolytic variables. RESULTS: On both study days, bradykinin and substance P caused dose-dependent vasodilatation and release of t-PA from the infused forearm (p < 0.05 by analysis of variance [ANOVA]). Long-term ACE inhibitor therapy caused an increase in forearm vasodilatation (p < 0.05 by ANOVA) and t-PA release (p < 0.001 by ANOVA) during bradykinin, but not substance P, infusion. Maximal local plasma t-PA activity concentrations approached 100 IU/ml, and maximal forearm protein release was approximately 4.5 microg/min. CONCLUSIONS: Long-term ACE inhibitor therapy augments bradykinin-induced peripheral vasodilatation and local t-PA release in patients with HF due to ischemic heart disease. Local plasma t-PA activity concentrations approached those seen during systemic thrombolytic therapy for acute myocardial infarction. This may contribute to the primary mechanism of the anti-ischemic effects associated with long-term ACE inhibitor therapy.


Assuntos
Bradicinina/farmacologia , Gliceraldeído-3-Fosfato Desidrogenases/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Fragmentos de Peptídeos/uso terapêutico , Ativador de Plasminogênio Tecidual/metabolismo , Idoso , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Pletismografia , Substância P , Sistema Vasomotor/efeitos dos fármacos
18.
J Epidemiol Community Health ; 59(6): 475-80, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15911643

RESUMO

OBJECTIVE: To quantify the direct and indirect effects of fetal (position in family, weight, and social class at birth), childhood (breast feeding, growth, infections, and social class in childhood, age at menarche), and adult life (social class, alcohol consumption, smoking, diet, reproductive history, exercise, hormone replacement therapy use), and adult size (height, weight) on bone health at age 49-51 years, as measured by bone mineral density, total scanned bone area of the hip and lumbar spine, and femoral neck shaft angle. DESIGN: Follow up study of the Newcastle thousand families birth cohort established in 1947. PARTICIPANTS: 171 men and 218 women who attended for dual energy x ray absorptiometry scanning. MAIN RESULTS: Fetal life explained around 6% of variation in adult bone mineral density for men, but accounted for less than 1% for women. Adult lifestyle, including effects mediated through adult weight accounted for over 10% of variation in density for men and around 6% for women. Almost half of variation in bone area for men was explained by early life. However, most of this was mediated through achieved adult height and weight. In women, less than 5% of variation in bone area was accounted for by early life, after adjusting for adult size. Most of the variation in each of the indicators for both sexes was contributed either directly or indirectly by adult lifestyle and achieved adult height and weight. CONCLUSIONS: The effect of fetal life on bone health in adulthood seems to be mediated through achieved adult height.


Assuntos
Densidade Óssea/fisiologia , Osso e Ossos/anatomia & histologia , Absorciometria de Fóton , Antropometria , Peso ao Nascer , Estatura/fisiologia , Peso Corporal/fisiologia , Criança , Estudos de Coortes , Feminino , Colo do Fêmur/anatomia & histologia , Seguimentos , Articulação do Quadril/anatomia & histologia , Humanos , Lactente , Recém-Nascido , Estilo de Vida , Vértebras Lombares/anatomia & histologia , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Classe Social
19.
Arterioscler Thromb Vasc Biol ; 24(6): 1043-8, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15105283

RESUMO

BACKGROUND: Bradykinin is an endogenous vasodilator that may contribute to the systemic effects of angiotensin-converting enzyme (ACE) inhibitor therapy. Using B9340, a bradykinin receptor antagonist, we determined the contribution of bradykinin to the systemic hemodynamic effects of long-term ACE inhibition in patients with chronic heart failure. METHODS AND RESULTS: Fourteen patients with heart failure received enalapril (10 mg twice daily) or losartan (50 mg twice daily) in a randomized double-blind crossover trial. After 6 weeks treatment, patients underwent right heart catheterization and were randomized to an intravenous infusion of B9340 (2 to 20 microg/kg per minute) or saline placebo. After B9340 infusion in patients treated with enalapril, mean arterial pressure (+5.2 mm Hg), systemic vascular resistance (+315 dynes x s/cm5), pulmonary arterial wedge pressure (-1.4 mm Hg), and mean pulmonary arterial pressure (-1.3 mm Hg) were greater compared with losartan (P<0.005, P=0.07, P<0.0001, and P<0.05 respectively) or placebo infusion (P< or =0.005 for all). There was a reduction in cardiac output after B9340 with enalapril compared with placebo (P<0.001) but not losartan. CONCLUSIONS: Bradykinin contributes to the systemic hemodynamic effects of long-term ACE inhibition in patients with heart failure. This mechanism may explain the apparent clinical differences between ACE inhibitors and angiotensin receptor blockers in the treatment of heart failure.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Antagonistas dos Receptores da Bradicinina , Bradicinina/análogos & derivados , Bradicinina/farmacologia , Bradicinina/fisiologia , Enalapril/farmacologia , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/fisiologia , Idoso , Angiotensina II/sangue , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Bradicinina/uso terapêutico , Débito Cardíaco/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Enalapril/uso terapêutico , Feminino , Antebraço/irrigação sanguínea , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/tratamento farmacológico , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Humanos , Losartan/farmacologia , Losartan/uso terapêutico , Masculino , Pessoa de Meia-Idade , Peptidil Dipeptidase A/sangue , Fluxo Sanguíneo Regional/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
20.
Arterioscler Thromb Vasc Biol ; 23(9): 1667-70, 2003 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-12869356

RESUMO

OBJECTIVE: We sought to assess pharmacodynamic responses to the bradykinin antagonist B9340 and to determine the contribution of the endothelial bradykinin receptor to stimulated tissue plasminogen activator (t-PA) release in humans. METHODS AND RESULTS: Bilateral forearm blood flow and plasma fibrinolytic variables were measured in 8 volunteers during 100 minutes of intrabrachial infusions of saline placebo, B9340 at 4.5 nmol/min, or B9340 at 13.5 nmol/min. On each occasion, intra-arterial bradykinin (30 to 3000 pmol/min) and substance P (4 to 16 pmol/min) were coinfused for 10 minutes at each dose. To assess the onset and offset of action, 6 additional subjects on 2 occasions received intra-arterial bradykinin (100 pmol/min) for 60 minutes with a coinfusion of either saline placebo or B9340 (13.5 nmol/min) for 12 minutes. During placebo infusion, bradykinin and substance P caused dose-dependent vasodilatation in the infused forearm (P<0.001). B9340 caused a dose-dependent inhibition of bradykinin-induced forearm vasodilatation and t-PA release (P<0.001) without affecting substance P-induced vasodilatation or t-PA release (P=NS). B9340 caused a reversible inhibition of bradykinin-induced vasodilatation (P<0.001) with a rapid onset and offset of action. CONCLUSIONS: B9340 is a potent, reversible, and selective competitive receptor antagonist of bradykinin-induced vasodilatation and t-PA release in humans.


Assuntos
Antagonistas dos Receptores da Bradicinina , Bradicinina/análogos & derivados , Bradicinina/farmacologia , Ativador de Plasminogênio Tecidual/metabolismo , Adulto , Bradicinina/administração & dosagem , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Antebraço/irrigação sanguínea , Humanos , Infusões Intravenosas , Masculino , Fluxo Sanguíneo Regional/efeitos dos fármacos , Projetos de Pesquisa , Vasodilatação/efeitos dos fármacos
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