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1.
Conserv Biol ; : e14296, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770838

RESUMO

Marine protected areas (MPAs) globally serve conservation and fisheries management goals, generating positive effects in some marine ecosystems. Surf zones and sandy beaches, critical ecotones bridging land and sea, play a pivotal role in the life cycles of numerous fish species and serve as prime areas for subsistence and recreational fishing. Despite their significance, these areas remain understudied when evaluating the effects of MPAs. We compared surf zone fish assemblages inside and outside MPAs across 3 bioregions in California (USA). Using seines and baited remote underwater videos (BRUVs), we found differences in surf zone fish inside and outside MPAs in one region. Inside south region MPAs, we observed higher abundance (Tukey's honest significant difference [HSD] = 0.83, p = 0.0001) and richness (HSD = 0.22, p = 0.0001) in BRUVs and greater biomass (HSD = 0.32, p = 0.0002) in seine surveys compared with reference sites. Selected live-bearing, fished taxa were positively affected by MPAs. Elasmobranchs displayed greater abundance in BRUV surveys and higher biomass in seine surveys inside south region MPAs (HSD = 0.35, p = 0.0003 and HSD = 0.23, p = 0.008, respectively). Although we observed no overall MPA signal for Embiotocidae, abundances of juvenile and large adult barred surfperch (Amphistichus argenteus), the most abundant fished species, were higher inside MPAs (K-S test D = 0.19, p < 0.0001). Influence of habitat characteristics on MPA performance indicated surf zone width was positively associated with fish abundance and biomass but negatively associated with richness. The south region had the largest positive effect size on all MPA performance metrics. Our findings underscored the variability in species richness and composition across regions and survey methods that significantly affected differences observed inside and outside MPAs. A comprehensive assessment of MPA performance should consider specific taxa, their distribution, and the effects of habitat factors and geography.


Evaluación de la influencia de las áreas marinas protegidas sobre los peces de la zona de rompientes Resumen Las áreas marinas protegidas (AMP) cumplen los objetivos de conservación y manejo de pesquerías a nivel mundial, lo que genera efectos positivos en algunos ecosistemas marinos. Las zonas de rompientes y las playas arenosas, ecotonos importantes que conectan la tierra con el mar, tienen un papel esencial en el ciclo de vida de varios peces y fungen como áreas óptimas para la pesca recreativa y de sustento. A pesar de su importancia, estas áreas están poco estudiadas con respecto a la evaluación del efecto de las AMP. Comparamos la composición de peces del área de rompientes dentro y fuera de las AMP de tres bioregiones de California, EUA. Usamos chinchorros y videos submarinos con carnada (BRUVs) y descubrimos diferencias en los peces de la zona de rompientes dentro y fuera de las AMP en una región. Dentro de las AMP de la región sur observamos una mayor abundancia (diferencia significativa honesta de Tukey [DSH]  =  0.83, p = 0.0001) y riqueza (DSH  =  0.22, p = 0.0001) en los BRUV y una mayor biomasa (DSH  =  0.32, p = 0.0002) en los censos con chinchorro en comparación con los sitios de referencia. Los taxones seleccionados de peces de sustento fueron afectados de manera positiva por las AMP. Los elasmobranquios mostraron una mayor abundancia en los BRUV y una mayor biomasa en los censos con chinchorro dentro de las AMP de la región sur (DSH  =  0.35, p = 0.0003 y DSH  =  0.23, p = 0.008, respectivamente). Aunque no observamos una señal generalizada de las AMP para la familia Embiotocidae, la abundancia de Amphistichus argenteus juveniles y adultos, la especie pescada más abundante, fue mayor dentro de las AMP (prueba K­S D  =  0.19, p < 0.0001). La influencia de las características del hábitat sobre el desempeño de las AMP indicó que el ancho de la zona de rompientes está asociado de forma positiva con la abundancia y biomasa de los peces, pero de forma negativa con la riqueza. La región sur tuvo el mayor tamaño de efecto positivo sobre todas las medidas de desempeño de las AMP. Nuestros hallazgos destacan la variabilidad en la riqueza y composición de especies en todas las regiones y los censos que afectan significativamente las diferencias observadas dentro y fuera de las AMP. Una evaluación completa del desempeño de las AMP debe considerar taxones específicos, su distribución y el efecto de los factores de hábitat y la geografía.

2.
J Pediatr ; 257: 113384, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36931493

RESUMO

OBJECTIVES: To evaluate the effectiveness of newborn screening for sickle cell disease in eastern Jamaica by determining what proportion of screen-positive infants were registered with the Sickle Cell Unit by 2 months (60 days) of age and identifying parents' perceptions of facilitators and barriers impacting age at registration. STUDY DESIGN: This cross-sectional study used a mixed method approach. Ages at diagnosis confirmation and first clinic visit were recorded for screen-positive infants born between February 1, 2015, and November 15, 2017. All parents were invited to complete the survey, and early and late attendees were invited to participate in the qualitative aspect of the study. A researcher-designed questionnaire and an interview guide based on the Capability, Opportunity, Motivation, Behavior, and health belief models examined factors that may affect time to registration. Quantitative data were analyzed to yield descriptive statistics using Stata®v14. All interview data were coded. Similar codes were grouped together into themes. RESULTS: Most (97.7%) of the 133 screen-positive infants had their diagnosis confirmed. Only 40% had their first clinic visit by age 60 days. Denial of the diagnosis, poor communication, and the costs of treatment and transportation were perceived barriers to registration, whereas family support was a facilitator. CONCLUSIONS: Diagnosis confirmation was almost universal, but most infants did not attend clinic by 2 months of age. In-depth interviews have identified several facilitators and barriers that can be targeted to improve early registration.


Assuntos
Anemia Falciforme , Recém-Nascido , Humanos , Lactente , Jamaica , Estudos Transversais , Anemia Falciforme/diagnóstico , Triagem Neonatal , Pais
3.
J Virol ; 93(22)2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31462564

RESUMO

In mice, resistance to central nervous system (CNS) disease induced by members of the genus Flavivirus is conferred by an allele of the 2'-5' oligoadenylate synthetase 1b gene that encodes the inactive full-length protein (Oas1b-FL). The susceptibility allele encodes a C-terminally truncated protein (Oas1b-tr). We show that the efficiency of neuron infection in the brains of resistant and susceptible mice is similar after an intracranial inoculation of two flaviviruses, but amplification of viral proteins and double-stranded RNA (dsRNA) is inhibited in infected neurons in resistant mouse brains at later times. Active OAS proteins detect cytoplasmic dsRNA and synthesize short 2'-5'-linked oligoadenylates (2'-5'A) that interact with the latent endonuclease RNase L, causing it to dimerize and cleave single-stranded RNAs. To evaluate the contribution of RNase L to the resistance phenotype in vivo, we created a line of resistant RNase L-/- mice. Evidence of RNase L activation in infected RNase L+/+ mice was indicated by higher levels of viral RNA in the brains of infected RNase L-/- mice. Activation of type I interferon (IFN) signaling was detected in both resistant and susceptible brains, but Oas1a and Oas1b mRNA levels were lower in RNase L+/+ mice of both types, suggesting that activated RNase L also has a proflaviviral effect. Inhibition of virus replication was robust in resistant RNase L-/- mice, indicating that activated RNase L is not a critical factor in mediating this phenotype.IMPORTANCE The mouse genome encodes a family of Oas proteins that synthesize 2'-5'A in response to dsRNA. 2'-5'A activates the endonuclease RNase L to cleave single-stranded viral and cellular RNAs. The inactive, full-length Oas1b protein confers flavivirus-specific disease resistance. Although similar numbers of neurons were infected in resistant and susceptible brains after an intracranial virus infection, viral components amplified only in susceptible brains at later times. A line of resistant RNase L-/- mice was used to evaluate the contribution of RNase L to the resistance phenotype in vivo Activation of RNase L antiviral activity by flavivirus infection was indicated by increased viral RNA levels in the brains of RNase L-/- mice. Oas1a and Oas1b mRNA levels were higher in infected RNase L-/- mice, indicating that activated RNase L also have a proflaviviral affect. However, the resistance phenotype was equally robust in RNase L-/- and RNase L+/+ mice.


Assuntos
2',5'-Oligoadenilato Sintetase/metabolismo , Endorribonucleases/metabolismo , Infecções por Flavivirus/metabolismo , 2',5'-Oligoadenilato Sintetase/fisiologia , Nucleotídeos de Adenina/genética , Nucleotídeos de Adenina/metabolismo , Animais , Linhagem Celular , Endorribonucleases/genética , Endorribonucleases/fisiologia , Flavivirus/metabolismo , Infecções por Flavivirus/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oligorribonucleotídeos/genética , Oligorribonucleotídeos/metabolismo , Fenótipo , RNA Viral/metabolismo , Ribonucleases/genética , Ribonucleases/metabolismo , Replicação Viral/efeitos dos fármacos
4.
Regul Toxicol Pharmacol ; 101: 121-134, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30468762

RESUMO

Computational approaches are increasingly used to predict toxicity due, in part, to pressures to find alternatives to animal testing. Read-across is the "new paradigm" which aims to predict toxicity by identifying similar, data rich, source compounds. This assumes that similar molecules tend to exhibit similar activities i.e. molecular similarity is integral to read-across. Various of molecular fingerprints and similarity measures may be used to calculate molecular similarity. This study investigated the value and concordance of the Tanimoto similarity values calculated using six widely used fingerprints within six toxicological datasets. There was considerable variability in the similarity values calculated from the various molecular fingerprints for diverse compounds, although they were reasonably concordant for homologous series acting via a common mechanism. The results suggest generic fingerprint-derived similarities are likely to be optimally predictive for local datasets, i.e. following sub-categorisation. Thus, for read-across, generic fingerprint-derived similarities are likely to be most predictive after chemicals are placed into categories (or groups), then similarity is calculated within those categories, rather than for a whole chemically diverse dataset.


Assuntos
Alternativas aos Testes com Animais , Medição de Risco , Conjuntos de Dados como Assunto , Substâncias Perigosas/química , Substâncias Perigosas/toxicidade , Estrutura Molecular , Relação Estrutura-Atividade , Testes de Toxicidade
5.
Psychol Health Med ; 24(4): 470-480, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30318923

RESUMO

The current study examines gender effects on disease knowledge and quality of life in adolescents with sickle cell disease (SCD) in Jamaica. We report the baseline results on 76 girls and 74 boys with mean age (16.9 ± 1.8 vs. 16.2 ±2.0 years), recruited in a larger intervention study. Girls had higher knowledge scores (15.3 ± 4.2 vs. 13.3 ± 4.2 p=.004), poorer overall QOL scores (70.1 ± 19.6 vs. 77.2 ± 17.8 p=0.02) but similar severity scores to boys. Girls also had significantly lower scores on many QOL domain scores: Pain occurrences over the course the past month (Pain and Hurt:77.49 ± 23.3 vs. 85.37 ± 17.13); concerns about seeking health services for pain (Worry1:63.73 ± 26.21 vs. 75.33 ± 24.62); confidence in self-management & treatment effects (Treatment: 72.25 ± 23.6 vs. 80.73 ± 18.90) and SCD disclosure & empathy from others (Communication II: 47.44 ± 1.02 vs. 61.71 ± 29.41). Knowledge was positively predicted by age, higher education, greater household possessions and was higher in girls; whereas QOL was lower in girls and those with greater disease severity and higher with higher education. In conclusion, there is a significant gender differential in disease knowledge and QOL among adolescents with SCD. Interventions will need to address the lower QOL in girls and lower disease knowledge among boys.


Assuntos
Anemia Falciforme/psicologia , Qualidade de Vida , Adolescente , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Jamaica , Masculino , Análise de Regressão , Autogestão , Fatores Sexuais , Inquéritos e Questionários
6.
Breast Cancer Res Treat ; 172(1): 179-190, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30039288

RESUMO

PURPOSE: Experimental laboratory data have indicated a protective effect of vitamin D on breast cancer progression, while epidemiological evidence is growing. Using pharmacy claims data, this study investigates the association between vitamin D supplement use initiated after a breast cancer diagnosis and associated mortality. METHODS: Women aged 50-80 years with a record of invasive breast cancer were identified on the National Cancer Registry Ireland database (n = 5417). Initiation of de novo vitamin D post-diagnosis was identified from linked national prescription data (n = 2581, 49%). Multivariate Cox proportional hazards models were used to estimate adjusted HRs (95% CIs) for breast cancer-specific mortality. RESULTS: There was a 20% reduction in breast cancer-specific mortality in de novo vitamin D users (modelled as a time-varying variable) compared to non-users (HR 0.80; 95% CI 0.64-0.99, p = 0.048) and the reduction was greater at 49% (HR 0.51; 95% CI 0.34-0.74, p < 0.001), if vitamin D was initiated soon after the breast cancer diagnosis (within 6 months). CONCLUSIONS: In this large national breast cancer cohort, de novo vitamin D use post-diagnosis was found to be associated with a reduction in breast cancer-specific mortality. Vitamin D, therefore, has the potential as a non-toxic and inexpensive agent to improve survival in breast cancer patients. Findings support the need for RCTs exploring the effect of vitamin D supplementation on breast cancer survival.


Assuntos
Neoplasias da Mama/dietoterapia , Sobreviventes de Câncer , Suplementos Nutricionais , Vitamina D/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Mama/anormalidades , Mama/patologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Feminino , Humanos , Hipertrofia/dietoterapia , Hipertrofia/epidemiologia , Hipertrofia/patologia , Irlanda/epidemiologia , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais
7.
Photosynth Res ; 137(2): 227-239, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29524035

RESUMO

We address a challenge in the engineering of proteins to redirect electron transfer pathways, using the bacterial photosynthetic reaction centre (RC) pigment-protein complex. Direct electron transfer is shown to occur from the QA quinone of the Rhodobacter sphaeroides RC containing a truncated H protein and bound on the quinone side to a gold electrode. In previous reports of binding to the quinone side of the RC, electron transfer has relied on the use of a soluble mediator between the RC and an electrode, in part because the probability of QB quinone reduction is much greater than that of direct electron transfer through the large cytoplasmic domain of the H subunit, presenting a ~ 25 Å barrier. A series of C-terminal truncations of the H subunit were created to expose the quinone region of the RC L and M proteins, and all truncated RC H mutants assembled in vivo. The 45M mutant was designed to contain only the N-terminal 45 amino acid residues of the H subunit including the membrane-spanning α-helix; the mutant RC was stable when purified using the detergent N-dodecyl-ß-D-maltoside, contained a near-native ratio of bacteriochlorophylls to bacteriopheophytins, and showed a charge-separated state of [Formula: see text]. The 45M-M229 mutant RC had a Cys residue introduced in the vicinity of the QA quinone on the newly exposed protein surface for electrode attachment, decreasing the distance between the quinone and electrode to ~ 12 Å. Steady-state photocurrents of up to around 200 nA/cm2 were generated in the presence of 20 mM hydroquinone as the electron donor to the RC. This novel configuration yielded photocurrents orders of magnitude greater than previous reports of electron transfer from the quinone region of RCs bound in this orientation to an electrode.


Assuntos
Transporte de Elétrons/fisiologia , Complexo de Proteínas do Centro de Reação Fotossintética/fisiologia , Rhodobacter sphaeroides/metabolismo , Coenzimas , DNA Bacteriano/genética , Técnicas Eletroquímicas , Escherichia coli , Modelos Moleculares , Mutagênese Sítio-Dirigida , Mutação , Pigmentos Biológicos , Conformação Proteica , Subunidades Proteicas
8.
Stat Med ; 37(10): 1682-1695, 2018 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-29380409

RESUMO

Blood pressure (BP) fluctuates throughout the day. The pattern it follows represents one of the most important circadian rhythms in the human body. For example, morning BP surge has been suggested as a potential risk factor for cardiovascular events occurring in the morning, but the accurate quantification of this phenomenon remains a challenge. Here, we outline a novel method to quantify morning surge. We demonstrate how the most commonly used method to model 24-hour BP, the single cosinor approach, can be extended to a multiple-component cosinor random-effects model. We outline how this model can be used to obtain a measure of morning BP surge by obtaining derivatives of the model fit. The model is compared with a functional principal component analysis that determines the main components of variability in the data. Data from the Mitchelstown Study, a population-based study of Irish adults (n = 2047), were used where a subsample (1207) underwent 24-hour ambulatory blood pressure monitoring. We demonstrate that our 2-component model provided a significant improvement in fit compared with a single model and a similar fit to a more complex model captured by b-splines using functional principal component analysis. The estimate of the average maximum slope was 2.857 mmHg/30 min (bootstrap estimates; 95% CI: 2.855-2.858 mmHg/30 min). Simulation results allowed us to quantify the between-individual SD in maximum slopes, which was 1.02 mmHg/30 min. By obtaining derivatives we have demonstrated a novel approach to quantify morning BP surge and its variation between individuals. This is the first demonstration of cosinor approach to obtain a measure of morning surge.


Assuntos
Pressão Sanguínea/fisiologia , Ritmo Circadiano/fisiologia , Análise de Componente Principal , Simulação por Computador , Feminino , Humanos , Irlanda , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Tempo
9.
Child Care Health Dev ; 44(3): 501-506, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29436011

RESUMO

BACKGROUND: Increasing knowledge and understanding of disease is known to improve outcomes in persons living with a chronic illness. In this paper, we aim to compare the disease knowledge of children with sickle cell disease (SCD), age 6-10 years, who received an intervention (an educational colouring book on SCD) geared towards improving disease knowledge, to those who did not received the colouring book. METHODS: A quasi-experimental study was conducted where disease knowledge was determined in 56 children who had received the colouring book and compared to 60 children who did not receive this intervention. RESULTS: The mean knowledge score was significantly higher in the intervention group (mean difference = 2.65; 95% CI [1.43, 3.86]), as well as in older children and in those in higher grades but there was no difference between sexes. In a multiple regression model (adjusted R2 : 0.39; p value < .001), knowledge score was significantly higher in those who received the intervention (ß: 2.62; 95% CI [1.48, 3.76]) while adjusting for age, gender, persons living at home, and the father's employment status. CONCLUSION: The study highlights that a simple, inexpensive (cost: US$1/book) child-friendly intervention can significantly improve knowledge about SCD even in young children. It also underlines various social factors that are associated with children's understanding of their disease.


Assuntos
Anemia Falciforme/psicologia , Serviços de Saúde da Criança , Conhecimentos, Atitudes e Prática em Saúde , Educação de Pacientes como Assunto , Anemia Falciforme/economia , Criança , Serviços de Saúde da Criança/economia , Serviços de Saúde da Criança/organização & administração , Análise Custo-Benefício , Feminino , Inquéritos Epidemiológicos , Humanos , Jamaica , Masculino , Educação de Pacientes como Assunto/economia , Educação de Pacientes como Assunto/métodos
10.
J Physiol ; 593(19): 4319-39, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26136181

RESUMO

KEY POINTS: The superficial spinal dorsal horn contains a heterogeneous population of neurons that process sensory inputs. Information on the properties of excitatory interneurons in this region is limited. As calretinin is a protein thought to be restricted to an excitatory population in this region, the aim of this study was to characterize calretinin-expressing neurons. Most calretinin cells (85%) exhibited large A-type potassium currents and delayed firing action potential discharge, and received strong excitatory synaptic input, whereas the remainder exhibited hyperpolarization-activated cation currents and low threshold T-type calcium currents, and tonic- or initial bursting firing patterns, and received weak excitatory synaptic input. These respective features are consistent with properties of excitatory and inhibitory interneuron populations in this region of the spinal cord. Our findings have resolved a previously unidentified population of inhibitory interneurons. Furthermore, the contrasting excitability patterns of excitatory and inhibitory calretinin-expressing neurons suggest that they play distinct roles in spinal sensory processing circuits. ABSTRACT: Neurons in the superficial dorsal horn (SDH) of the spinal cord play an important role in nociceptive, thermal, itch and light touch sensations. Excitatory interneurons comprise ∼65% of all SDH neurons but surprisingly few studies have investigated their role in spinal sensory processing. Here we use a transgenic mouse to study putative excitatory SDH neurons that express the calcium binding protein calretinin (CR). Our immunocytochemical, morphological and electrophysiological analysis identified two distinct populations of CR-expressing neurons, which we termed 'Typical' and 'Atypical'. Typical CR-expressing neurons comprised ∼85% of the population and exhibited characteristic excitatory interneuron properties including delayed firing discharge, large rapid A-type potassium currents, and central, radial or vertical cell morphologies. Atypical neurons exhibited properties consistent with inhibitory interneurons, including tonic firing or initial bursting discharge, Ih currents, and islet cell morphology. Although both Typical and Atypical CR-expressing neurons responded to noxious peripheral stimulation, the excitatory drive onto Typical CR-expressing neurons was much stronger. Furthermore, Atypical CR-expressing cells comprise at least two functionally distinct subpopulations based on their responsiveness to noxious peripheral stimulation and neurochemical profile. Together our data suggest CR expression is not restricted to excitatory neurons in the SDH. Under normal conditions, the contribution of 'Typical' excitatory CR-expressing neurons to overall SDH excitability may be limited by the presence of A-type potassium currents, which limit the effectiveness of their strong excitatory input. Their contribution may, however, be increased in pathological situations where A-type potassium currents are decreased. By contrast, 'Atypical' inhibitory neurons with their excitable phenotype but weak excitatory input may be more easily recruited during increased peripheral stimulation.


Assuntos
Calbindina 2/fisiologia , Células do Corno Posterior/fisiologia , Animais , Calbindina 2/genética , Calbindina 2/metabolismo , Feminino , Masculino , Potenciais da Membrana , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Dor/fisiopatologia , Células do Corno Posterior/metabolismo
11.
Arch Toxicol ; 89(5): 733-41, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24888375

RESUMO

This study outlines the analysis of 94 chemicals with repeat dose toxicity data taken from Scientific Committee on Consumer Safety opinions for commonly used hair dyes in the European Union. Structural similarity was applied to group these chemicals into categories. Subsequent mechanistic analysis suggested that toxicity to mitochondria is potentially a key driver of repeat dose toxicity for chemicals within each of the categories. The mechanistic hypothesis allowed for an in silico profiler consisting of four mechanism-based structural alerts to be proposed. These structural alerts related to a number of important chemical classes such as quinones, anthraquinones, substituted nitrobenzenes and aromatic azos. This in silico profiler is intended for grouping chemicals into mechanism-based categories within the adverse outcome pathway paradigm.


Assuntos
Simulação por Computador , Tinturas para Cabelo/toxicidade , Interpretação Estatística de Dados , Tinturas para Cabelo/química , Humanos , Mitocôndrias/efeitos dos fármacos , Modelos Biológicos , Relação Estrutura-Atividade
12.
Int J Sports Med ; 36(1): 41-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25259591

RESUMO

This study compared the intensity distribution of time-motion analysis data, when speed zones were categorized by different methods. 12 U18 players undertook a routine battery of laboratory- and field-based assessments to determine their running speed corresponding to the respiratory compensation threshold (RCT), maximal aerobic speed (MAS), maximal oxygen consumption (vV˙O2max) and maximal sprint speed (MSS). Players match-demands were tracked using 5 Hz GPS units in 22 fixtures (50 eligible match observations). The percentage of total distance covered running at high-speed (%HSR), very-high speed (%VHSR) and sprinting were determined using the following speed thresholds: (1) arbitrary; (2) individualised (IND) using RCT, vV˙O2max and MSS; (3) individualised via MAS per se; (4) individualised via MSS per se; and (5) individualised using MAS and MSS as measures of locomotor capacities (LOCO). Using MSS in isolation resulted in 61% and 39% of player's % HSR and % VHSR, respectively, being incorrectly interpreted, when compared to the IND technique. Estimating the RCT from fractional values of MAS resulted in erroneous interpretations of % HSR in 50% of cases. The present results suggest that practitioners and researchers should avoid using singular fitness characteristics to individualise the intensity distribution of time-motion analysis data. A combination of players' anaerobic threshold, MAS, and MSS characteristics are recommended to individualise player-tracking data.


Assuntos
Aptidão Física/fisiologia , Corrida/fisiologia , Estudos de Tempo e Movimento , Adolescente , Limiar Anaeróbio , Sistemas de Informação Geográfica , Humanos , Consumo de Oxigênio , Futebol/fisiologia
13.
Photosynth Res ; 120(1-2): 197-205, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23765434

RESUMO

A new gene expression system was developed in Rhodobacter sphaeroides, replacing a pRK415-based system used previously. The broad host-range IPTG-inducible plasmid pIND4 was used to create the plasmid pIND4-RC1 for expression of the puhA and pufQBALMX genes, encoding the reaction centre (RC) and light-harvesting complex 1 (LH1) proteins. The strain R. sphaeroides ΔRCLH was used to make a knockout of the rshI restriction endonuclease gene, enabling electroporation of DNA into the bacterium; a subsequent knockout of ppsR was made, creating the strain R. sphaeroides RCx lacking this oxygen-sensing repressor of the photosynthesis gene cluster. Using pIND4-RC1, LH1 levels were increased by a factor of about 8 over pRS1 per cell in cultures grown semi-aerobically. In addition, the ppsR knockout allowed for photosynthetic pigment-protein complex synthesis in the presence of high concentrations of molecular oxygen; here, LH1 levels per cell increased by 20 % when grown under high aeration conditions. A new medium (called RLB) is the E. coli medium LB supplemented with MgCl2 and CaCl2, which was found to increase growth rates and final cell culture densities, with an increase of 30 % of LH1 per cell detected in R. sphaeroides RCx(pIND4-RC1) grown in RLB versus LB medium. Furthermore, cell density was about three times greater in RLB compared to semi-aerobic conditions. The combination of all the modifications resulted in an increase of LH1 and RC per mL of culture volume by approximately 35-fold, and a decrease in the length of culture incubation time from about 5 days to ~36 h.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Complexo de Proteínas do Centro de Reação Fotossintética/isolamento & purificação , Rhodobacter sphaeroides/metabolismo , Meios de Cultura/farmacologia , Rhodobacter sphaeroides/efeitos dos fármacos , Rhodobacter sphaeroides/crescimento & desenvolvimento
14.
West Indian Med J ; 63(2): 147-50, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25303249

RESUMO

Newborn screening (NBS) for sickle cell disease (SCD) has occurred in Jamaica since 1973 in two periods, the most recent being since 1995. As a result of NBS, significant lessons have been learnt about management of the disease. Additionally, significant improvements in morbidity and mortality of children affected with the disease have occurred because of the implementation of simple interventions. Unfortunately, in a country where the burden of disease is high compared to other countries, only approximately 40% of children born in Jamaica currently benefit from NBS. As such, the future of NBS for SCD in Jamaica lies in island-wide screening. There are challenges including the lack of appropriate governance and policy structures, the technology for high-volume processing and comprehensive care clinics throughout the island. On the other hand, the significant strides made in disease management, the strength and model of care of the Sickle Cell Unit, delicately balancing limited resources and increased survival cannot be disparaged. Therefore, consistent with the World Health Organization's recommendation, we are working toward achieving island-wide screening for SCD, to ensure equitable access to continued improvements in morbidity, mortality and quality of life.

15.
Conserv Physiol ; 12(1): coae034, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827188

RESUMO

Estimating the survival probability of animals released from fisheries can improve the overall understanding of animal biology with implications for fisheries management, conservation and animal welfare. Vitality indicators are simple visual measures of animal condition that change in response to stressors (like fisheries capture) and can be assessed to predict post-release survival. These indicators typically include immediate reflex responses which are typically combined into a score. Vitality indicators are straight-forward and non-invasive metrics that allow users to quantify how close (or far) an animal is from a normal, 'healthy' or baseline state, which in turn can be correlated with outcomes such as survival probability, given appropriate calibration. The literature on using vitality indicators to predict post-release survival of animals has grown rapidly over the past decade. We identified 136 papers that used vitality indicators in a fisheries context. These studies were primarily focused on marine and freshwater fishes, with a few examples using herptiles and crustaceans. The types of vitality indicators are diverse and sometimes taxa-specific (e.g. pinching leg of turtles, spraying water at nictitating membrane of sharks) with the most commonly used indicators being those that assess escape response or righting response given the vulnerability of animals when those reflexes are impaired. By presenting Pacific salmon fisheries as a case study, we propose a framework for using vitality indicators to predict survival across taxa and fisheries.

16.
Diabet Med ; 30(10): 1198-203, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23659572

RESUMO

OBJECTIVES: Pre-diabetes is an important indicator of future diabetes burden and many countries are reporting prevalence estimates of pre-diabetes. To date in Ireland, estimates of the prevalence of pre-diabetes were unavailable. Our objectives were to estimate the prevalence of pre-diabetes in a nationally representative sample of Irish adults and to explore determinants of pre-diabetes. METHODS: The Survey of Lifestyle Attitudes and Nutrition 2007 was a cross-sectional survey on health and lifestyle in a nationally representative sample of Irish adults. Analysis was performed on a subsample of 1132 participants ≥ 45 years who provided blood samples. Determination of pre-diabetes was based on American Diabetes Association HbA1c cut points of 39-46 mmol/mol (5.7-6.4%). To explore determinants, we modelled pre-diabetes prevalence as a function of a set of health system and socio-demographic variables using logistic regression. RESULTS: The overall weighted prevalence estimate of pre-diabetes in participants ≥ 45 years was 19.8% (95% CI 16.4-23.9). There was no significant difference between age or gender-specific prevalence rates. Obesity was significantly associated with pre-diabetes on univariate and multivariate analysis. Population attributable fraction estimates for excess BMI, physical inactivity and poor diet as causes of pre-diabetes were 31.3% (95% CI -3.9 to 54.5), 10.0% (95% CI -2.7 to 21.3) and 6.1% (95% CI -4.9 to 15.9), respectively. CONCLUSIONS: The high levels of pre-diabetes detected in this study are worrying. Population level interventions to address diet and lifestyle factors are needed urgently to prevent progression to diabetes in high-risk individuals.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Progressão da Doença , Comportamentos Relacionados com a Saúde , Obesidade/epidemiologia , Estado Pré-Diabético , Idoso , Atitude , Glicemia , Índice de Massa Corporal , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/prevenção & controle , Comportamento Alimentar , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Irlanda/epidemiologia , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Obesidade/sangue , Obesidade/complicações , Obesidade/prevenção & controle , Vigilância da População , Estado Pré-Diabético/sangue , Estado Pré-Diabético/epidemiologia , Estado Pré-Diabético/prevenção & controle , Prevalência , Comportamento Sedentário
17.
Crit Rev Toxicol ; 43(7): 537-58, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23875763

RESUMO

The ability of a compound to cause adverse effects to the liver is one of the most common reasons for drug development failures and the withdrawal of drugs from the market. Such adverse effects can vary tremendously in severity, leading to an array of possible drug-induced liver injuries (DILIs). As a result, it is not surprising that drug development has evolved into a complex and multifaceted process including methods aiming to identify potential liver toxicities. Unfortunately, hepatotoxicity remains one of the most complex and poorly understood areas of human toxicity; thus it is a significant challenge to identify potential hepatotoxins. The performance of existing methods to identify hepatotoxicity requires improvement. The current study details a scheme for generating chemical categories and the development of structural alerts able to identify potential hepatotoxins. The study utilized a diverse 951-compound dataset and used structural similarity methods to produce a number of structurally restricted categories. From these categories, 16 structural alerts associated with observed human hepatotoxicity were developed. Furthermore, the mechanism(s) by which these compounds cause hepatotoxicity were investigated and a mechanistic rationale was proposed, where possible, to yield mechanistically supported structural alerts. Alerts of this nature have the potential to be used in the screening of compounds to highlight potential hepatotoxicity, whilst the chemical categories themselves are important in applying read-across approaches. The scheme presented in this study also has the potential to act as a knowledge generator serving as an excellent starting platform from which to conduct additional toxicological studies.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/patologia , Fígado/efeitos dos fármacos , Preparações Farmacêuticas/química , Toxicologia/métodos , Relação Dose-Resposta a Droga , Humanos , Fígado/patologia , Relação Estrutura-Atividade
18.
Pediatr Surg Int ; 29(3): 305-10, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23274700

RESUMO

PURPOSE: The objective of this study was to characterize the clinical course and outcomes of children with pancreatic pseudocysts that were initially treated non-operatively or with percutaneous drainage. METHODS: A retrospective review of children with pancreatic pseudocysts over a 12-year period was completed. Categorical variables were compared using Fischer's exact method and the Student's t test was used to compare continuous variables. Analysis was done using logistic and linear regression models. RESULTS: Thirty-six children met the criteria for pancreatic pseudocyst and 33 children were treated either non-operatively or with percutaneous drainage. Of the 22 children managed non-operatively, 17 required no additional intervention (77 %) and five required surgery. Operative procedures were: Frey procedure (3), distal pancreatectomy (1), and cystgastrostomy (1). Eight of the 11 children treated with initial percutaneous drainage required no additional treatment (72 %). The other three children underwent distal pancreatectomy. Success of non-operative management or percutaneous drainage was not dependent on size or complexity of the pseudocyst Logistic regression did not identify any patient demographic (gender, age, and weight), etiologic (trauma, non-traumatic pancreatitis) or pseudocyst characteristic (size, septations) that predicted failure of non-operative therapy. CONCLUSIONS: In children, pancreatic pseudocysts can frequently be managed without surgery regardless of size or complexity of the pseudocyst. When an intervention is needed, percutaneous drainage can be performed successfully, avoiding the need for major surgical intervention in the majority of patients.


Assuntos
Drenagem/métodos , Pseudocisto Pancreático/terapia , Adolescente , Criança , Pré-Escolar , Feminino , Gastrostomia , Humanos , Lactente , Modelos Logísticos , Masculino , Pancreatectomia , Pseudocisto Pancreático/etiologia , Pancreaticojejunostomia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
19.
Anal Chem ; 84(14): 5869-75, 2012 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-22816778

RESUMO

Second order nonlinear optical imaging of chiral crystals (SONICC) and two-photon excited fluorescence measurements [both autofluorescence and two-photon excited UV-fluorescence (TPE-UVF)] were assessed for the selective detection of APIs relative to common pharmaceutical excipients. Active pharmaceutical ingredients (APIs) compose only a small percentage of most tabulated formulations, yet the API distribution within the tablet can affect drug release and tablet stability. Complementary measurements using either UV-SONICC (266 nm detection) or TPE-UVF were shown to generate signals >50-fold more intense for a model API (griseofulvin) than those produced by common pharmaceutical excipients. The combined product of the measurements produced signals >10(4)-fold greater than the excipients studied. UV-SONICC or TPE-UVF produced greater selectivity than analogous measurements with visible-light detection, attributed to the presence of aromatic moieties within the API exhibiting strong one and two photon absorption at ~266 nm. Complementary SONICC and fluorescence measurements allowed for the sensitive detection of the three-dimensional distribution of tadalafil within a Cialis tablet to a depth of >140 µm.


Assuntos
Excipientes/química , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Fenômenos Ópticos , Preparações Farmacêuticas/química , Raios Ultravioleta , Carbolinas/química , Griseofulvina/química , Pós , Estereoisomerismo , Comprimidos , Tadalafila
20.
J Chem Inf Model ; 51(5): 975-85, 2011 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-21488656

RESUMO

It is important that in silico models for use in chemical safety legislation, such as REACH, are compliant with the OECD Principles for the Validation of (Q)SARs. Structural alert models can be useful under these circumstances but lack an adequately defined applicability domain. This paper examines several methods of domain definition for structural alert models with the aim of assessing which were the most useful. Specifically, these methods were the use of fragments, chemical descriptor ranges, structural similarity, and specific applicability domain definition software. Structural alerts for mutagenicity in Derek for Windows (DfW) were used as examples, and Ames test data were used to define and test the domain of chemical space where the alerts produce reliable results. The usefulness of each domain was assessed on the criterion that confidence in the correctness of predictions should be greater inside the domain than outside it. By using a combination of structural similarity and chemical fragments a domain was produced where the majority of correct positive predictions for mutagenicity were within the domain and a large proportion of the incorrect positive predictions outside it. However this was not found for the negative predictions; there was little difference between the percentage of true and false predictions for inactivity which were found as either within or outside the applicability domain. A hypothesis for the occurrence of this difference between positive and negative predictions is that differences in structure between training and test compounds are more likely to remove the toxic potential of a compound containing a structural alert than to add an unknown mechanism of action (structural alert) to a molecule which does not already contain an alert. This could be especially true for well studied end points such as the Ames assay where the majority of mechanisms of action are likely to be known.


Assuntos
Citotoxinas/química , Modelos Químicos , Mutagênicos/química , Software , Algoritmos , Simulação por Computador , Funções Verossimilhança , Relação Quantitativa Estrutura-Atividade
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