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1.
J Fish Biol ; 92(5): 1651-1656, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29624685

RESUMO

Around 30% of Atlantic salmon Salmo salar smolts successfully survived passage through Loch Meig, a reservoir in the north of Scotland, en route to the sea. However, this survival rate was in turn dependent on the timing of migration, with the earliest migrants in the spring having the best chance of survival. This could have implication for fisheries management, since the estimation of smolt downstream survival may be influenced by which time period of the smolt run is analysed.


Assuntos
Migração Animal , Salmo salar/fisiologia , Estações do Ano , Animais , Oceanos e Mares , Rios , Escócia , Fatores de Tempo
2.
J Fish Biol ; 92(3): 569-578, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29537092

RESUMO

Groups of wild-reared Atlantic salmon Salmo salar smolts were captured during their seaward migration on a tributary of the River Conon, Scotland, U.K., from 1999 to 2014 and tagged with passive integrated transponders (PIT). Fish that subsequently returned to the river after growing at sea were recorded automatically by a PIT-detector in a fish pass. Return rate was related directly to length and condition and inversely to day of the year that the smolt was tagged. Over years, as the study progressed, there was a significant increase in the proportion of smolts returning after two or more years at sea and no trend in returns of salmon having spent one winter at sea. There was no trend in the date of return of salmon across the study period. Fish that had spent more winters at sea returned earlier in the year.


Assuntos
Migração Animal , Salmo salar/fisiologia , Animais , Tamanho Corporal , Rios , Salmo salar/anatomia & histologia , Escócia , Estações do Ano , Fatores de Tempo
3.
Mol Ecol ; 25(21): 5425-5438, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27662635

RESUMO

A larger body size confers many benefits, such as increased reproductive success, ability to evade predators and increased competitive ability and social status. However, individuals rarely maximize their growth rates, suggesting that this carries costs. One such cost could be faster attrition of the telomeres that cap the ends of eukaryotic chromosomes and play an important role in chromosome protection. A relatively short telomere length is indicative of poor biological state, including poorer tissue and organ performance, reduced potential longevity and increased disease susceptibility. Telomere loss during growth may also be accelerated by environmental factors, but these have rarely been subjected to experimental manipulation in the natural environment. Using a wild system involving experimental manipulations of juvenile Atlantic salmon Salmo salar in Scottish streams, we found that telomere length in juvenile fish was influenced by parental traits and by direct environmental effects. We found that faster-growing fish had shorter telomeres and there was a greater cost (in terms of reduced telomere length) if the growth occurred in a harsher environment. We also found a positive association between offspring telomere length and the growth history of their fathers (but not mothers), represented by the number of years fathers had spent at sea. This suggests that there may be long-term consequences of growth conditions and parental life history for individual longevity.


Assuntos
Salmo salar/crescimento & desenvolvimento , Salmo salar/genética , Encurtamento do Telômero , Telômero/ultraestrutura , Animais , Tamanho Corporal , Meio Ambiente , Feminino , Longevidade , Masculino , Escócia
4.
Ecology ; 94(3): 618-26, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23687888

RESUMO

Both the environments experienced by a mother as a juvenile and an adult can affect her investment in offspring. However, the implications of these maternal legacies, both juvenile and adult, for offspring fitness in natural populations are unclear. We investigated whether the juvenile growth rate and adult reproductive traits (length, body condition, and reproductive investment at spawning) of female wild Atlantic salmon (Salmo salar) were related to the growth and survival of their offspring. Adult salmon captured on their upstream migration were used to create experimental full-sib clutches of eggs, which were mixed and then placed in artificial nests in a natural stream that lacked salmon due to a migration barrier. Four months later we resampled the stream to obtain family-level estimates of offspring size and survival. Mothers that had grown slowly as juveniles (as determined by scalimetry) but had invested heavily in reproduction (egg production for a given body length) and were in relatively poor body condition (somatic mass for a given body length) at spawning produced the largest eggs. Larger eggs resulted in larger juveniles and higher juvenile survival. However, after controlling for egg size, offspring growth was positively related to maternal juvenile growth rate and reproductive investment. The predictors of offspring survival (i.e., reproductive success) varied with the juvenile growth rate of the mother: If females grew slowly as juveniles, their reproductive success was negatively related to their own body condition. In contrast, the reproductive success of females that grew quickly as juveniles was instead related positively to their own body condition. Our results show that maternal influences on offspring in the wild can be complex, with reproductive success related to the early life performance of the mother, as well as her state at the time of breeding.


Assuntos
Salmo salar/crescimento & desenvolvimento , Salmo salar/fisiologia , Animais , Animais Selvagens , Composição Corporal , Peso Corporal , Feminino , Reprodução/fisiologia
5.
J Fish Biol ; 77(4): 927-34, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20840620

RESUMO

Radio telemetry was utilized to track 38 Atlantic salmon Salmo salar across space and time during and following their spawning run on the Conon system, Scotland. The data collected were used to assess the proportion of S. salar able to migrate successfully from an upland oligotrophic area of the catchment and the distribution of the carcasses of those fish that remained. Of these fish, 35% successfully migrated from the study area after the spawning period. The fish that remained were distributed approximately equally between riverine and lacustrine areas, but with a strong tendency to accumulate in regions of relatively slow water flows.


Assuntos
Migração Animal , Reprodução , Salmo salar/fisiologia , Animais , Feminino , Modelos Logísticos , Masculino , Rios , Escócia , Telemetria
6.
Comput Biol Med ; 69: 44-51, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26717240

RESUMO

We propose a novel computational approach to automatically identify the fetal heart rate patterns (fHRPs), which are reflective of sleep/awake states. By combining these patterns with presence or absence of movements, a fetal behavioral state (fBS) was determined. The expert scores were used as the gold standard and objective thresholds for the detection procedure were obtained using Receiver Operating Characteristics (ROC) analysis. To assess the performance, intraclass correlation was computed between the proposed approach and the mutually agreed expert scores. The detected fHRPs were then associated to their corresponding fBS based on the fetal movement obtained from fetal magnetocardiogaphic (fMCG) signals. This approach may aid clinicians in objectively assessing the fBS and monitoring fetal wellbeing.


Assuntos
Feto , Magnetocardiografia/métodos , Terceiro Trimestre da Gravidez , Gravidez , Processamento de Sinais Assistido por Computador , Feminino , Humanos
7.
J Epidemiol Community Health ; 59(11): 920-3, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16234417

RESUMO

Primary care and public health both work to improve the population's health. The potential benefits of improved integration between these disciplines have however not been fully seen because of the lack of a structured way to deliver the integration. This article reviews the benefits, models of working, and challenges to the integration of public health and primary care. General practitioners with special interests (GPwSI) have now been created and formally recognised in clinical roles in the United Kingdom. It is proposed that the creation of GPwSI in public health offers an ideal model of a way of achieving integration and ensuring public health is delivered in primary care.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Medicina de Família e Comunidade/organização & administração , Papel do Médico , Atenção Primária à Saúde/organização & administração , Saúde Pública , Política de Saúde , Humanos , Medicina Estatal , Reino Unido
8.
J Perinatol ; 35(8): 660-4, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25836321

RESUMO

OBJECTIVE: We sought to compare the long-term neurodevelopmental outcomes of late preterm, early term and term infants while controlling for a wide range of maternal complications and comorbidities. STUDY DESIGN: Data for the study was obtained from the South Carolina Medicaid claims and vital records databases from 1 January 2000 to 31 December 2003. We included infants weighing between 1500 and 4500 g, born between 34 0/7 and 41 6/7 weeks, and with no congenital anomalies. Outcome measures were based on the presence of ICD-9-CM codes for attention deficit hyperactivity disorders and developmental speech or language disorders. RESULT: A total of 3270 late preterm (LPIs), 11,527 early term (ETIs) and 24,005 term infants met the eligibility criteria. Rates for all outcome variables were statistically significant and elevated for LPI, but adjusted hazard ratios (AHRs) were only significant for the risk of developmental speech and/or language delay (LPI: AHR 1.36 95% confidence interval (CI) 1.23 to 1.50; ETI: AHR 1.27 95% CI 1.17 to 1.37). CONCLUSION: Late preterm and early term deliveries have adverse long-term neurodevelopmental outcomes, and these outcomes should be considered when determining the timing of delivery.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Classificação Internacional de Doenças/normas , Transtornos do Desenvolvimento da Linguagem/epidemiologia , Nascimento Prematuro/economia , Pré-Escolar , Bases de Dados Factuais , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Masculino , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Retrospectivos , South Carolina , Nascimento a Termo
9.
Biotechnol Prog ; 9(3): 317-22, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7763701

RESUMO

The growth of Agrobacterium transformed "hairy root" cultures of Hyoscyamus muticus was examined in various liquid- and gas-dispersed bioreactor configurations. Reactor runs were replicated to provide statistical comparisons of nutrient availability on culture performance. Accumulated tissue mass in submerged air-sparged reactors was 31% of gyratory shake-flask controls. Experiments demonstrate that poor performance of sparged reactors is not due to bubble shear damage, carbon dioxide stripping, settling, or flotation of roots. Impaired oxygen transfer due to channeling and stagnation of the liquid phase are the apparent causes of poor growth. Roots grown on a medium-perfused inclined plane grew at 48% of gyratory controls. This demonstrates the ability of cultures to partially compensate for poor liquid distribution through vascular transport of nutrients. A reactor configuration in which the medium is sprayed over the roots and permitted to drain down through the root tissue was able to provide growth rates which are statistically indistinguishable (95% T-test) from gyratory shake-flask controls. In this type of spray/trickle-bed configuration, it is shown that distribution of the roots becomes a key factor in controlling the rate of growth. Implications of these results regarding design and scale-up of bioreactors to produce fine chemicals from root cultures are discussed.


Assuntos
Biotecnologia/métodos , Desenvolvimento Vegetal , Técnicas de Cultura , Gases
10.
Med Hypotheses ; 7(2): 201-5, 1981 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6261100

RESUMO

Tumor cells have an absence or deficiency of mitochondrial superoxide dismutase. Superoxide is produced when hematoporphyrin derivative is exposed to visible light. A significant portion of the antitumor effect of porphyrin:light therapy is hypothesized to be mediated by superoxide.


Assuntos
Hematoporfirinas/efeitos da radiação , Luz , Neoplasias/radioterapia , Oxigênio/metabolismo , Superóxidos/metabolismo , Humanos , Modelos Biológicos , Neoplasias/metabolismo , Nitroazul de Tetrazólio , Oxirredução , Superóxido Dismutase/metabolismo
11.
Ann R Coll Surg Engl ; 69(4): 185-7, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3631878

RESUMO

An audit of mortality following operation was performed over ten years classifying deaths into those that were 'expected' and 'unexpected'. 'Unexpected' deaths were defined as those in which, after careful consideration of the prevailing clinical circumstances at the time of operation, the probability of death following operation was felt to be low. This definition is a more helpful assessment of surgical performance than overall perioperative mortality as it highlights cases where improvements in surgical management might be achieved. In audits involving surgical mortality, the classification of deaths into 'expected' and 'unexpected' is recommended.


Assuntos
Auditoria Médica , Procedimentos Cirúrgicos Operatórios/mortalidade , Hospitalização , Humanos , Período Pós-Operatório
12.
Ann R Coll Surg Engl ; 71(1): 37-9, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2923417

RESUMO

One hundred asymptomatic patients over 60 years of age who had cholecystectomy carried out at least 10 years earlier underwent double contrast barium enema and sigmoidoscopy. The incidence of colorectal adenomas and carcinomas was compared with age and sex matched controls undergoing routine post mortems. In the post-cholecystectomy group 12% had tumours (8 adenomas greater than 1 cm in diameter, 4 carcinomas). In the control group 3% had tumours (3 adenomas); P = 0.02. This study confirms that patients with a history of cholecystectomy have an increased risk of developing colorectal adenomas and carcinomas.


Assuntos
Adenoma/etiologia , Carcinoma/etiologia , Colecistectomia/efeitos adversos , Neoplasias do Colo/etiologia , Neoplasias Retais/etiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
13.
Ulster Med J ; 59(1): 36-40, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2349747

RESUMO

A twelve year prospective wound audit was undertaken in an academic surgical unit. Data from 10,000 operations were analysed. Overall, wound infection rates decreased during this time. Infection rates in contaminated wounds in particular fell from 19.2% to 4.7%. This decrease in wound infection may be related in part to a change in the antibiotic prophylactic regimen and in part to the institution of the wound sepsis audit which provided regular information on the unit infection rates. This audit permitted early detection of adverse trends, and may have had a direct influence on surgical techniques.


Assuntos
Infecção da Ferida Cirúrgica/epidemiologia , Cefalosporinas/uso terapêutico , Humanos , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/tratamento farmacológico , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
14.
Ulster Med J ; 71(1): 30-3, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12137161

RESUMO

Duodenal obstruction may be caused by inoperable malignant disease. Symptoms of nausea and vomiting have been traditionally palliated by surgery. The aim of the study was to determine the efficacy of the endoscopic placement of metal self expanding duodenal stents for the palliation of malignant duodenal obstruction. Four patients with malignant gastric outlet obstruction are described. One patient had a history of oesophagectomy for oesophageal adenocarcinoma and presented with further dysphagia. At endoscopy the recurrent oesophageal tumour and an adenocarcinoma involving the pylorus were both stented. In the other three patients there was a previous history of colonic carcinoma, cholangiocarcinoma and oesophageal adenocarcinoma respectively. All four patients were successfully stented with good palliation of their symptoms. Duodenal Wallstents are a useful alternative to surgery in patients with inoperable malignant duodenal obstruction or those who are unfit for surgery.


Assuntos
Obstrução Duodenal/terapia , Obstrução da Saída Gástrica/terapia , Neoplasias Gastrointestinais/terapia , Cuidados Paliativos/métodos , Stents , Idoso , Obstrução Duodenal/etiologia , Duodenoscopia , Feminino , Obstrução da Saída Gástrica/etiologia , Neoplasias Gastrointestinais/complicações , Humanos , Masculino , Pessoa de Meia-Idade
15.
Placenta ; 35(2): 125-31, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24333048

RESUMO

As the conduit for nutrients and growth signals, the placenta is critical to establishing an environment sufficient for fetal growth and development. To better understand the mechanisms regulating placental development and gene expression, we characterized the transcriptome of term placenta from 20 healthy women with uncomplicated pregnancies using RNA-seq. To identify genes that were highly expressed and unique to the placenta we compared placental RNA-seq data to data from 7 other tissues (adipose, breast, hear, kidney, liver, lung, and smooth muscle) and identified several genes novel to placental biology (QSOX1, DLG5, and SEMA7A). Semi-quantitative RT-PCR confirmed the RNA-seq results and immunohistochemistry indicated these proteins were highly expressed in the placental syncytium. Additionally, we mined our RNA-seq data to map the relative expression of key developmental gene families (Fox, Sox, Gata, Tead, and Wnt) within the placenta. We identified FOXO4, GATA3, and WNT7A to be amongst the highest expressed members of these families. Overall, these findings provide a new reference for understanding of placental transcriptome and can aid in the identification of novel pathways regulating placenta physiology that may be dysregulated in placental disease.


Assuntos
Placenta/metabolismo , Transcriptoma , Antígenos CD/biossíntese , Sequência de Bases , Proteínas de Ciclo Celular , Feminino , Fatores de Transcrição Forkhead , Fator de Transcrição GATA3/biossíntese , Proteínas Ligadas por GPI/biossíntese , Perfilação da Expressão Gênica , Humanos , Proteínas de Membrana/biossíntese , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/biossíntese , Gravidez , Semaforinas/biossíntese , Distribuição Tecidual , Fatores de Transcrição/biossíntese , Proteínas Supressoras de Tumor/biossíntese , Proteínas Wnt/biossíntese
17.
Ann Biomed Eng ; 39(3): 964-72, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21140290

RESUMO

Changes in fetal magnetocardiographic (fMCG) signals are indicators for fetal body movement. We propose a novel approach to reliably extract fetal body movements based on the field strength of the fMCG signal independent of its frequency. After attenuating the maternal MCG, we use a Hilbert transform approach to identify the R-wave. At each R-wave, we compute the center-of-gravity (cog) of the coordinate positions of MCG sensors, each weighted by the magnitude of the R-wave amplitude recorded at the corresponding sensor. We then define actogram as the distance between the cog computed at each R-wave and the average of the cog from all the R-waves in a 3-min duration. By applying a linear de-trending approach to the actogram we identify the fetal body movement and compare this with the synchronous occurrence of the acceleration in the fetal heart rate. Finally, we apply this approach to the fMCG recorded simultaneously with ultrasound from a single subject and show its improved performance over the QRS-amplitude based approach in the visually verified movements. This technique could be applied to transform the detection of fetal body movement into an objective measure of fetal health and enhance the predictive value of prevalent clinical testing for fetal wellbeing.


Assuntos
Algoritmos , Diagnóstico por Computador/instrumentação , Diagnóstico por Computador/métodos , Eletrodos , Monitorização Fetal/métodos , Movimento Fetal/fisiologia , Magnetocardiografia/métodos , Desenho de Equipamento , Feminino , Humanos , Gravidez , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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