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1.
Sci Rep ; 14(1): 1898, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253660

RESUMO

Escalating environmental threats to coral reefs coincides with global advancements in coral restoration programs. To improve long-term efficacy, practitioners must consider incorporating genotypes resilient to ocean warming and disease while maintaining genetic diversity. Identifying such genotypes typically occurs under long-term exposures that mimic natural stressors, but these experiments can be time-consuming, costly, and introduce tank effects, hindering scalability for hundreds of nursery genotypes used for outplanting. Here, we evaluated the efficacy of the acute Coral Bleaching Automated Stress System (CBASS) against long-term exposures on the bleaching response of Acropora cervicornis, the dominant restoration species in Florida's Coral Reef. Comparing bleaching metrics, Fv/Fm, chlorophyll, and host protein, we observed similar responses between the long-term heat and the CBASS treatment of 34.3 °C, which was also the calculated bleaching threshold. This suggests the potential of CBASS as a rapid screening tool, with 90% of restoration genotypes exhibiting similar bleaching tolerances. However, variations in acute bleaching phenotypes arose from measurement timing and experiment heat accumulation, cautioning against generalizations solely based on metrics like Fv/Fm. These findings identify the need to better refine the tools necessary to quickly and effectively screen coral restoration genotypes and determine their relative tolerance for restoration interventions.


Assuntos
Antozoários , Animais , Antozoários/genética , Recifes de Corais , Benchmarking , Bioensaio , Clorofila
2.
Br Dent J ; 235(9): 670, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37945840
3.
Int. j. morphol ; 39(5): 1493-1501, oct. 2021. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1385512

RESUMO

SUMMARY: This study evaluates the effect of probiotics Saccharomyces cerevisiae, Lactobacillus acidophilus and Bacillus subtilis on production parameters and intestinal histomorphology of broilers of 45 days of age. Eleven 45-day-old Ross 500 broilers were used and classified as control group (CG) (n = 5) or supplemented with probiotics group (n = 8). Histopathological evaluation of duodenum, ileum, and jejunum was performed. The area of the villi height, base and apex were evaluated as well as the size and number of crypts. In addition, mucus production was quantified in different portions of the small intestine. The villi present duodenum of broilers supplemented with probiotics had a greater area (p = 0.0127), a greater basal width (p = 0.0049) and a greater apical width (p = 0.0024), as well as a greater crypt area (p = 0.0189). Significantly higher levels of mucus were noted in the duodenum (p = 0.0480) and jejunum (p = 0.0480) of broilers supplemented with probiotics. We suggest that probiotic supplementation improve the intestinal nutrients absorption.


RESUMEN: Este estudio evalúa el efecto del uso de probióticos como: Saccharomyces cerevisiae, Lactobacillus acidophilus, Bacillus subtilis en parámetros productivos e histomorfologia intestinal de pollos de engorde de 45 días de edad. Fueron usados 11, los cuales fueron clasificados en grupo control (CG) (n = 5) y grupo suplementado con probióticos (PG) (n = 8). Fue realizado análisis histopatológico de secciones de duodeno, íleon y yeyuno. Fue evaluado ancho, altura y área del ápice de la vellosidad, área y número de criptas. Además, fue estimada la producción de moco en los diferentes segmentos del intestino delgado. Fue observada mayor área de la vellosidad en duodeno, PG (p = 0.0127), ancho basal mayor en PG (p = 0.0049) ancho apical mayor en PG (p = 0.0024), así como mayor área de criptas en PG (p = 0.0189). No fueron encontradas diferencias significativas respecto a los segmentos de yeyuno e íleon. PG presentó mayor producción de moco en duodeno (p = 0.0480) y en yeyuno (p = 0.0480). Concluimos que la suplementación con probióticos en pollos de engorde genera cambios en la histomorfologia intestinal, evidenciables en áreas apicales y basales de las vellosidades intestinales. Soporte financiero: Dirección General de Investigaciones - Universidad de los Llanos.


Assuntos
Animais , Aves Domésticas , Probióticos/administração & dosagem , Intestinos/anatomia & histologia , Saccharomyces cerevisiae/fisiologia , Bacillus subtilis/fisiologia , Galinhas , Suplementos Nutricionais , Intestinos/microbiologia , Lactobacillus acidophilus/fisiologia
4.
Immunohematology ; 37(1): 33-43, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33962490

RESUMO

While a variety of therapeutic options continue to emerge for COVID-19 treatment, convalescent plasma (CP) has been used as a possible treatment option early in the pandemic. One of the most significant challenges with CP therapy, however, both when defining its efficacy and implementing its approach clinically, is accurately and efficiently characterizing an otherwise heterogenous therapeutic treatment. Given current limitations, our goal is to leverage a SARS antibody testing platform with a newly developed automated endpoint titer analysis program to rapidly define SARS-CoV-2 antibody levels in CP donors and hospitalized patients. A newly developed antibody detection platform was used to perform a serial dilution enzyme-linked immunosorbent assay (ELISA) for immunoglobulin (Ig)G, IgM, and IgA SARS-CoV-2 antibodies. Data were then analyzed using commercially available software, GraphPad Prism, or a newly developed program developed in Python called TiterScape, to analyze endpoint titers. Endpoint titer calculations and analysis times were then compared between the two analysis approaches. Serial dilution analysis of SARS-CoV-2 antibody levels revealed a high level of heterogeneity between individuals. Commercial platform analysis required significant time for manual data input and extrapolated endpoint titer values when the last serial dilution was above the endpoint cutoff, occasionally producing erroneously high results. By contrast, TiterScape processed 1008 samples for endpoint titer results in roughly 14 minutes compared with the 8 hours required for the commercial software program analysis. Equally important, results generated by TiterScape and Prism were highly similar, with differences averaging 1.26 ± 0.2 percent (mean ± SD). The pandemic has created unprecedented challenges when seeking to accurately test large numbers of individuals for SARS-CoV-2 antibody levels with a rapid turnaround time. ELISA platforms capable of serial dilution analysis coupled with a highly flexible software interface may provide a useful tool when seeking to define endpoint titers in a high-throughput manner. Immunohematology 2021;37:33-43.While a variety of therapeutic options continue to emerge for COVID-19 treatment, convalescent plasma (CP) has been used as a possible treatment option early in the pandemic. One of the most significant challenges with CP therapy, however, both when defining its efficacy and implementing its approach clinically, is accurately and efficiently characterizing an otherwise heterogenous therapeutic treatment. Given current limitations, our goal is to leverage a SARS antibody testing platform with a newly developed automated endpoint titer analysis program to rapidly define SARS-CoV-2 antibody levels in CP donors and hospitalized patients. A newly developed antibody detection platform was used to perform a serial dilution enzyme-linked immunosorbent assay (ELISA) for immunoglobulin (Ig)G, IgM, and IgA SARS-CoV-2 antibodies. Data were then analyzed using commercially available software, GraphPad Prism, or a newly developed program developed in Python called TiterScape, to analyze endpoint titers. Endpoint titer calculations and analysis times were then compared between the two analysis approaches. Serial dilution analysis of SARS-CoV-2 antibody levels revealed a high level of heterogeneity between individuals. Commercial platform analysis required significant time for manual data input and extrapolated endpoint titer values when the last serial dilution was above the endpoint cutoff, occasionally producing erroneously high results. By contrast, TiterScape processed 1008 samples for endpoint titer results in roughly 14 minutes compared with the 8 hours required for the commercial software program analysis. Equally important, results generated by TiterScape and Prism were highly similar, with differences averaging 1.26 ± 0.2 percent (mean ± SD). The pandemic has created unprecedented challenges when seeking to accurately test large numbers of individuals for SARS-CoV-2 antibody levels with a rapid turnaround time. ELISA platforms capable of serial dilution analysis coupled with a highly flexible software interface may provide a useful tool when seeking to define endpoint titers in a high-throughput manner. Immunohematology 2021;37:33­43.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Anticorpos Antivirais , COVID-19/terapia , Ensaio de Imunoadsorção Enzimática , Humanos , Imunização Passiva , SARS-CoV-2 , Soroterapia para COVID-19
5.
J Appl Microbiol ; 131(5): 2212-2222, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33864329

RESUMO

AIMS: To investigate the binding of the antimicrobial compound 8-hydroxyquinoline (8HQ) to a material interface and to determine whether immobilization affects the antibacterial efficacy. METHODS AND RESULTS: The 8HQ derivative 5-carboxy-8-hydroxyquinoline (5C8HQ) was attached to silica beads through amide bond coupling at the carboxyl moiety of 5C8HQ. Attachment of 5C8HQ was confirmed using a combination of mass spectrometry, thermogravimetric analysis, colorimetric testing and Soxhlet extraction. Computational modelling results indicated that this substitution did not compromise the active sites on the molecule, whereas other positions on the ring system could potentially inhibit antimicrobial activity. The antibacterial effect of 8HQ and the 5C8HQ-modified silica complex against Escherichia coli 15597 (ATCC® 25922) and Staphylococcus aureus (ATCC 25923) was evaluated. CONCLUSIONS: The test results show that the immobilized 8HQ continues to exhibit antibacterial activity, however, quantifying the efficacy compared to free 8HQ bears further investigation. The expected antibacterial mechanism requires that the metal chelation site of 8HQ be retained and available after attachment to a surface. The retention of antibacterial activity after surface bonding represents a novel mechanism of action not previously reported. SIGNIFICANCE AND IMPACT OF THE STUDY: Recent changes in regulations due to environmental concerns prompted many companies and organizations to explore antimicrobial treatments that are chemically bound to the product. Chemically bonding biocidal compounds to a surface limits environmental release; however, molecular mechanisms that drive antibacterial activity when compounds are immobilized are limited. The results reported here demonstrate that the 8HQ reactive site retains antibacterial efficacy even after covalent attachment to a surface. This approach supersedes other antimicrobial treatments where the active component is gradually released from the material surface in order to elicit antimicrobial effects. This specific antibacterial activity of bound 8HQ represents a novel mechanism of action not previously reported, and a potential conduit to a new class of bound antimicrobial materials.


Assuntos
Oxiquinolina , Staphylococcus aureus , Antibacterianos/farmacologia , Escherichia coli , Testes de Sensibilidade Microbiana
6.
Domest Anim Endocrinol ; 75: 106595, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33307335

RESUMO

Insulin glargine (IGla) is a synthetic human-recombinant insulin analog that is used routinely in people as a q24h basal insulin. The 300 U/mL (U300) formulation of IGla is associated with longer duration of action and less within-day variability, making it a better basal insulin compared with the 100 U/mL (U100) formulation. We hypothesized that in healthy cats, IGlaU300 has a flatter time-action profile and longer duration of action compared with IGlaU100. Seven healthy neutered male, purpose-bred cats were studied in a randomized, crossover design. Pharmacodynamics of IGlaU100 and IGlaU300 (0.8 U/kg, subcutaneous) were determined by the isoglycemic clamp method. The time-action profile of IGlaU300 was flatter compared with IGlaU100 as demonstrated by lower peak (5.6 ± 1.1 mg/kg/min vs 8.3 ± 1.9 mg/kg/min, respectively; P = 0.04) with no difference in total metabolic effect (ME; P = 0.7) or duration of action (16.8 h ± 4.7 h vs 13.4 h ± 2.6 h; P = 0.2). The greater fraction of ME in the 12- to 24-h period postinjection (35 ± 23% vs 7 ± 8% respectively; P = 0.048) and lower intraday GIR% variability (7.8 ± 3.7% vs 17.4 ± 8.2% respectively; P = 0.03) supports a flatter time-action profile of IGlaU300. There were no differences in onset and end of the action. In summary, although both formulations have a similar duration of action that is well below 24 h, the ME of IGlaU300 is more evenly distributed over a 24 h period in healthy cats, making it a better candidate for once-daily injection in diabetics compared with IGlaU100.


Assuntos
Hipoglicemiantes , Insulina de Ação Prolongada , Animais , Glicemia/metabolismo , Gatos , Estudos Cross-Over , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Insulina Glargina/farmacologia , Insulina de Ação Prolongada/farmacologia , Masculino
7.
Transfus Clin Biol ; 28(1): 51-54, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33096207

RESUMO

OBJECTIVES: Examine possible pooling strategies designed to expand SARS-CoV-2 serological testing capacity. METHODS: Negative pools were assessed to determine optimal optical density (OD) cutoffs, followed by spiking weak or strong positive samples to assess initial assay performance. Samples were then randomly subjected to pool and individual testing approaches. RESULTS: Single positive specimens consistently converted pools of 5, 10, or 20 into positive outcomes. However, weaker IgG-positive samples failed to similarly convert pools of 50 to a positive result. In contrast, a stronger individual positive sample converted all pools tested into positive outcomes. Finally, examination of 150 samples configured into pools of 5, 10, 20 or 50 accurately predicted the presence of positive or negative specimens within each pool. CONCLUSIONS: These results suggest that pooling strategies may allow expansion of serological testing capacity. While limitations exist, such strategies may aid in large-scale epidemiological screening or identification of optimal convalescent plasma donors.


Assuntos
Anticorpos Antivirais/sangue , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina G/sangue , SARS-CoV-2/imunologia , Manejo de Espécimes/métodos , COVID-19/sangue , Teste Sorológico para COVID-19/instrumentação , Ensaio de Imunoadsorção Enzimática/instrumentação , Humanos , Nefelometria e Turbidimetria , Fatores de Tempo
8.
Rev Sci Instrum ; 89(5): 055117, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29864873

RESUMO

A coupled reflectometer-interferometer apparatus is described for thin-film thickness and curvature characterization in the three-phase contact line region of evaporating fluids. Validation reflectometry studies are provided for Au, Ge, and Si substrates and thin-film coatings of SiO2 and hydrogel/Ti/SiO2. For interferometry, liquid/air and solid/air interferences are studied, where the solid/air samples consisted of glass/air/glass wedges, cylindrical lenses, and molded polydimethylsiloxane lenses. The liquid/air studies are based on steady-state evaporation experiments of water and isooctane on Si and SiO2/Ti/SiO2 wafers. The liquid thin-films facilitate characterization of both (i) the nano-scale thickness of the absorbed fluid layer and (ii) the macro-scale liquid meniscus thickness, curvature, and curvature gradient profiles. For our validation studies with commercial lenses, the apparatus is shown to measure thickness profiles within 4.1%-10.8% error.

9.
Acta Physiol (Oxf) ; 223(2): e13039, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29356345

RESUMO

AIM: The aim of this study was to investigate the effects of 4 consecutive simulated night shifts on glucose homeostasis, mitochondrial function and central and peripheral rhythmicities compared with a simulated day shift schedule. METHODS: Seventeen healthy adults (8M:9F) matched for sleep, physical activity and dietary/fat intake participated in this study (night shift work n = 9; day shift work n = 8). Glucose tolerance and insulin sensitivity before and after 4 nights of shift work were measured by an intravenous glucose tolerance test and a hyperinsulinaemic euglycaemic clamp respectively. Muscles biopsies were obtained to determine insulin signalling and mitochondrial function. Central and peripheral rhythmicities were assessed by measuring salivary melatonin and expression of circadian genes from hair samples respectively. RESULTS: Fasting plasma glucose increased (4.4 ± 0.1 vs. 4.6 ± 0.1 mmol L-1 ; P = .001) and insulin sensitivity decreased (25 ± 7%, P < .05) following the night shift, with no changes following the day shift. Night shift work had no effect on skeletal muscle protein expression (PGC1α, UCP3, TFAM and mitochondria Complex II-V) or insulin-stimulated pAkt Ser473, pTBC1D4Ser318 and pTBC1D4Thr642. Importantly, the metabolic changes after simulated night shifts occurred despite no changes in the timing of melatonin rhythmicity or hair follicle cell clock gene expression across the wake period (Per3, Per1, Nr1d1 and Nr1d2). CONCLUSION: Only 4 days of simulated night shift work in healthy adults is sufficient to reduce insulin sensitivity which would be expected to increase the risk of T2D.


Assuntos
Relógios Biológicos/fisiologia , Ritmo Circadiano/fisiologia , Melatonina/metabolismo , Sono/fisiologia , Adulto , Glicemia/metabolismo , Feminino , Expressão Gênica/fisiologia , Humanos , Resistência à Insulina/fisiologia , Masculino , Pessoa de Meia-Idade , Admissão e Escalonamento de Pessoal
10.
J Dev Orig Health Dis ; 8(5): 618-625, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28975880

RESUMO

Low birth weight is associated with increased risk of cardiovascular disease in adulthood. Intrauterine growth restriction (IUGR) hearts have fewer CMs in early postnatal life, which may impair postnatal cardiovascular function and hence, explain increased disease risk, but whether the cardiomyocyte deficit persists to adult life is unknown. We therefore studied the effects of experimentally induced placental restriction (PR) on cardiac outcomes in young adult sheep. Heart size, cardiomyocyte number, nuclearity and size were measured in control (n=5) and PR (n=5) male sheep at 1 year of age. PR lambs were 36% lighter at birth (P=0.007), had 38% faster neonatal relative growth rates (P=0.001) and had 21% lighter heart weights relative to body weight as adults (P=0.024) than control lambs. Cardiomyocyte number, nuclearity and size in the left ventricle did not differ between control and PR adults; hearts of both groups contained cardiomyocytes (CM) with between one and four nuclei. Overall, cardiomyocyte number in the adult left ventricle correlated positively with birth weight but not with adult weight. This study is the first to demonstrate that intrauterine growth directly influences the complement of CM in the adult heart. Cardiomyocyte size was not correlated with cardiomyocyte number or birth weight. Our results suggest that body weight at birth affects lifelong cardiac functional reserve. We hypothesise that decreased cardiomyocyte number of low birth weight individuals may impair their capacity to adapt to additional challenges such as obesity and ageing.


Assuntos
Peso ao Nascer/fisiologia , Miocárdio/patologia , Miócitos Cardíacos/patologia , Fatores Etários , Animais , Contagem de Células/métodos , Tamanho Celular , Feminino , Previsões , Humanos , Masculino , Gravidez , Ovinos
11.
Community Dent Health ; 34(1): 4-7, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28561550

RESUMO

IMPETUS FOR ACTION: To conduct a user-friendly questionnaire survey of the oral health and service needs of adults with learning disabilities. SOLUTION: Researchers collaborated with local self-advocacy services to develop a questionnaire adapted from one used in a regional postal survey. The questionnaire, which covered dental status, oral health and dental services use, was sent to a random sample of people from the learning disability case register. OUTCOME: Of 2,000 questionnaires mailed, 117 were returned undelivered and 625 were completed (response rate 31.3%). The self-reported dental status of people with learning disabilities appeared similar to that of the 2008 postal survey of the general population in Sheffield. The major difference in dental status was 11.5% of people with learning disabilities wore upper dentures and 7.2% wore lower dentures, compared to 21.2% and 12.1% of the general population in Sheffield. CHALLENGES: Using the case register as a recruitment instrument may have excluded people with learning disabilities not registered. Time and finances only permitted one mailing. Analysis on the basis of deprivation could not be conducted. FUTURE IMPLICATIONS AND LEARNING POINTS: Contrary to current practice, it is possible to include people with learning disabilities in oral health surveys. A multidisciplinary team was essential for enabling the progression and implementation of inclusive research and for people with learning disabilities and their supporters to engage meaningfully. This level of collaboration appears necessary if we are committed to ensuring that people with learning disabilities and their supporters are made visible to policy and decision-makers.


Assuntos
Inquéritos de Saúde Bucal , Deficiências da Aprendizagem , Saúde Bucal , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
12.
Appl Radiat Isot ; 125: 9-14, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28390998

RESUMO

Current techniques for the measurement of radioactivity at various points during PET radiopharmaceutical production and R&D are based on the detection of the annihilation gamma rays from the radionuclide in the labelled compound. The detection systems to measure these gamma rays are usually variations of NaI or CsF scintillation based systems requiring costly and heavy lead shielding to reduce background noise. These detectors inherently suffer from low detection efficiency, high background noise and very poor linearity. They are also unable to provide any reasonably useful position information. A novel positron counting technique is proposed for the radioactivity assay during radiopharmaceutical manufacturing that overcomes these limitations. Detection of positrons instead of gammas offers an unprecedented level of position resolution of the radiation source (down to sub-mm) thanks to the nature of the positron interaction with matter. Counting capability instead of charge integration in the detector brings the sensitivity down to the statistical limits at the same time as offering very high dynamic range and linearity from zero to any arbitrarily high activity. This paper reports on a quantitative comparison between conventional detector systems and the proposed positron counting detector.

13.
Phys Chem Chem Phys ; 19(2): 1115-1121, 2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-27942685

RESUMO

A large class of colloidal multi-micron mesoporous silica particles have well-defined cylindrical nanopores, nanochannels which self-assembled in the templated sol-gel process. These particles are of broad interest in photonics, for timed drug release, enzyme stabilization, separation and filtration technologies, catalysis, etc. Although the pore geometry and mechanism of pore formation of such particles has been widely investigated at the nanoscale, their pore geometry and its formation mechanism at a larger (extended) scale is still under debate. The extended geometry of nanochannels is paramount for all aforementioned applications because it defines accessibility of nanochannels, and subsequently, kinetics of interaction of the nanochannel content with the particle surrounding. Here we present both experimental and theoretical investigation of the extended geometry and its formation mechanism in colloidal multi-micron mesoporous silica particles. We demonstrate that disordered (and consequently, well accessible) nanochannels in the initially formed colloidal particles gradually align and form extended self-sealed channels. This knowledge allows to control the percentage of disordered versus self-sealed nanochannels, which defines accessibility of nanochannels in such particles. We further show that the observed aligning the channels is in agreement with theory; it is thermodynamically favored as it decreases the Gibbs free energy of the particles. Besides the practical use of the obtained results, developing a fundamental understanding of the mechanisms of morphogenesis of complex geometry of nanopores will open doors to efficient and controllable synthesis that will, in turn, further fuel the practical utilization of these particles.

14.
J Endocrinol ; 232(2): 175-187, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27821470

RESUMO

Preterm birth is associated with increased risk of type 2 diabetes (T2D) in adulthood; however, the underlying mechanisms are poorly understood. We therefore investigated the effect of preterm birth at ~0.9 of term after antenatal maternal betamethasone on insulin sensitivity, secretion and key determinants in adulthood, in a clinically relevant animal model. Glucose tolerance and insulin secretion (intravenous glucose tolerance test) and whole-body insulin sensitivity (hyperinsulinaemic euglycaemic clamp) were measured and tissue collected in young adult sheep (14 months old) after epostane-induced preterm (9M, 7F) or term delivery (11M, 6F). Glucose tolerance and disposition, insulin secretion, ß-cell mass and insulin sensitivity did not differ between term and preterm sheep. Hepatic PRKAG2 expression was greater in preterm than in term males (P = 0.028), but did not differ between preterm and term females. In skeletal muscle, SLC2A4 (P = 0.019), PRKAA2 (P = 0.021) and PRKAG2 (P = 0.049) expression was greater in preterm than in term overall and in males, while INSR (P = 0.047) and AKT2 (P = 0.043) expression was greater in preterm than in term males only. Hepatic PRKAG2 expression correlated positively with whole-body insulin sensitivity in males only. Thus, preterm birth at 0.9 of term after betamethasone does not impair insulin sensitivity or secretion in adult sheep, and has sex-specific effects on gene expression of the insulin signalling pathway. Hence, the increased risk of T2D in preterm humans may be due to factors that initiate preterm delivery or in early neonatal exposures, rather than preterm birth per se.


Assuntos
Betametasona/farmacologia , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Resistência à Insulina/fisiologia , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Nascimento Prematuro , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Técnica Clamp de Glucose , Células Secretoras de Insulina/efeitos dos fármacos , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Gravidez , Fatores Sexuais , Ovinos , Carneiro Doméstico , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
15.
Pediatr Obes ; 12(6): 462-467, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-27417142

RESUMO

BACKGROUND: Paediatric observational studies demonstrate associations between sleep, television viewing and potential changes in daytime activity levels. OBJECTIVE(S): To determine whether experimental changes in sleep lead to changes in children's sedentary and physical activities. METHODS: Using a within-subject counterbalanced design, 37 children 8-11 years old completed a 3-week study. Children slept their typical amount during a baseline week and were then randomized to increase or decrease mean time in bed by 1.5 h/night for 1 week; the alternate schedule was completed the final week. Children wore actigraphs on their non-dominant wrist and completed 3-d physical activity recalls each week. RESULTS: Children reported watching more television (p < 0.001) and demonstrated lower daytime actigraph-measured activity counts per epoch (p = 0.03) when sleep was decreased (compared with increased). However, total actigraph-measured activity counts accrued throughout the entire waking period were higher when sleep was decreased (and children were awake for longer) than when it was increased (p < 0.001). CONCLUSION(S): Short sleep during childhood may lead to increased television viewing and decreased mean activity levels. Although additional time awake may help to counteract negative effects of short sleep, increases in reported sedentary activities could contribute to weight gain over time.


Assuntos
Exercício Físico/fisiologia , Comportamento Sedentário , Sono/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Recreação , Televisão , Fatores de Tempo
16.
J Dev Orig Health Dis ; 7(5): 548-562, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27335275

RESUMO

Intrauterine growth restriction (IUGR) and subsequent neonatal catch-up growth are implicated in the programming of increased appetite, adiposity and cardiometabolic diseases. Guinea pigs provide an alternate small animal model to rodents to investigate mechanisms underlying prenatal programming, being relatively precocial at birth, with smaller litter sizes and undergoing neonatal catch-up growth after IUGR. The current study, therefore, investigated postnatal consequences of spontaneous IUGR due to varying litter size in this species. Size at birth, neonatal, juvenile (post-weaning, 30-60 days) and adolescent (60-90 days) growth, juvenile and adolescent food intake, and body composition of young adults (120 days) were measured in 158 male and female guinea pigs from litter sizes of one to five pups. Compared with singleton pups, birth weight of pups from litters of five was reduced by 38%. Other birth size measures were reduced to lesser degrees with head dimensions being relatively conserved. Pups from larger litters had faster fractional neonatal growth and faster absolute and fractional juvenile growth rates (P<0.005 for all). Relationships of post-weaning growth, feed intakes and adult body composition with size at birth and neonatal growth rate were sex specific, with neonatal growth rates strongly and positively correlated with adiposity in males only. In conclusion, spontaneous IUGR due to large litter sizes in the guinea pig causes many of the programmed sequelae of IUGR reported in other species, including human. This may therefore be a useful model to investigate the mechanisms underpinning perinatal programming of hyperphagia, obesity and longer-term metabolic consequences.

17.
Geobiology ; 14(5): 457-68, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27027776

RESUMO

The ocean-atmosphere system is typically envisioned to have gone through a unidirectional oxygenation with significant oxygen increases in the earliest (ca. 635 Ma), middle (ca. 580 Ma), or late (ca. 560 Ma) Ediacaran Period. However, temporally discontinuous geochemical data and the patchy metazoan fossil record have been inadequate to chart the details of Ediacaran ocean oxygenation, raising fundamental debates about the timing of ocean oxygenation, its purported unidirectional rise, and its causal relationship, if any, with the evolution of early animal life. To better understand the Ediacaran ocean redox evolution, we have conducted a multi-proxy paleoredox study of a relatively continuous, deep-water section in South China that was paleogeographically connected with the open ocean. Iron speciation and pyrite morphology indicate locally euxinic (anoxic and sulfidic) environments throughout the Ediacaran in this section. In the same rocks, redox sensitive element enrichments and sulfur isotope data provide evidence for multiple oceanic oxygenation events (OOEs) in a predominantly anoxic global Ediacaran-early Cambrian ocean. This dynamic redox landscape contrasts with a recent view of a redox-static Ediacaran ocean without significant change in oxygen content. The duration of the Ediacaran OOEs may be comparable to those of the oceanic anoxic events (OAEs) in otherwise well-oxygenated Phanerozoic oceans. Anoxic events caused mass extinctions followed by fast recovery in biologically diversified Phanerozoic oceans. In contrast, oxygenation events in otherwise ecologically monotonous anoxic Ediacaran-early Cambrian oceans may have stimulated biotic innovations followed by prolonged evolutionary stasis.


Assuntos
Organismos Aquáticos/metabolismo , Fósseis , Sedimentos Geológicos/química , Água do Mar/química , Animais , China , Oceanos e Mares , Oxirredução
18.
BJOG ; 123(2): 244-53, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26841217

RESUMO

OBJECTIVE: To evaluate the effect of providing antenatal dietary and lifestyle advice on neonatal anthropometry, and to determine the inter-observer variability in obtaining anthropometric measurements. DESIGN: Randomised controlled trial. SETTING: Public maternity hospitals across metropolitan Adelaide, South Australia. POPULATION: Pregnant women with a singleton gestation between 10(+0) and 20(+0) weeks, and body mass index (BMI) ≥25 kg/m(2). METHODS: Women were randomised to either Lifestyle Advice (comprehensive dietary and lifestyle intervention over the course of pregnancy including dietary, exercise and behavioural strategies, delivered by a research dietician and research assistants) or continued Standard Care. Analyses were conducted using intention-to-treat principles. MAIN OUTCOME MEASURES: Secondary outcome measures for the trial included assessment of infant body composition using body circumference and skinfold thickness measurements (SFTM), percentage body fat, and bio-impedance analysis of fat-free mass. RESULTS: Anthropometric measurements were obtained from 970 neonates (488 Lifestyle Advice Group, and 482 Standard Care Group). In 394 of these neonates (215 Lifestyle Advice Group, and 179 Standard Care Group) bio-impedance analysis was also obtained. There were no statistically significant differences identified between those neonates born to women receiving Lifestyle Advice and those receiving Standard Care, in terms of body circumference measures, SFTM, percentage body fat, fat mass, or fat-free mass. The intra-class correlation coefficient for SFTM was moderate to excellent (0.55-0.88). CONCLUSIONS: Among neonates born to women who are overweight or obese, anthropometric measures of body composition were not modified by an antenatal dietary and lifestyle intervention.


Assuntos
Aconselhamento Diretivo/métodos , Comportamento Alimentar/psicologia , Obesidade/prevenção & controle , Assistência Perinatal/métodos , Complicações na Gravidez/prevenção & controle , Gestantes/psicologia , Adulto , Composição Corporal , Feminino , Humanos , Recém-Nascido , Estilo de Vida , Nova Zelândia/epidemiologia , Obesidade/epidemiologia , Obesidade/psicologia , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/psicologia , Austrália do Sul/epidemiologia , Resultado do Tratamento , Aumento de Peso
19.
Community Dent Health ; 33(4): 242-251, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28537359

RESUMO

The assessment of healthcare quality increasingly emphasises lay acceptability, as evidenced by the emergence of patient satisfaction and patient-centred care in the literature and in policy. In this paper we aim to provide a conceptual overview of acceptability and propose ways to enhance its assessment. Firstly, we map how acceptability's importance in quality assessments has increased and how the term acceptability has been used as synonymous with patient satisfaction, despite it being a broader concept. We then critique the concept of patient satisfaction and its measurement and challenge its use as an indicator of acceptability and quality. By drawing on our research and those of others, the second half of the paper describes how trust in clinicians and health services has emerged as a related concept, including a theoretical discussion of trust in healthcare outlining how it can be built, undermined and abused. We propose trust as an alternative indicator of acceptability in healthcare quality and review its measurement. Finally, we consider how healthcare policy may impact on trust and make recommendations for future research.


Assuntos
Satisfação do Paciente , Assistência Centrada no Paciente , Relações Médico-Paciente , Qualidade da Assistência à Saúde , Confiança , Coleta de Dados/métodos , Política de Saúde , Humanos , Opinião Pública
20.
Diabet Med ; 32(2): 174-80, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25407383

RESUMO

AIMS: To investigate whether maternal body size pre-pregnancy, gestational diabetes and weight gain are independently associated with subsequent insulin resistance in children; and to examine the potential mediating role of child's body size in any associations. METHODS: At 9-10 years, 443 children took part in a follow-up of a prospective cohort. Of those, 163 children elected to provide a fasting blood sample and child insulin resistance was estimated by homeostasis model assessment. Generalized linear models with log link function and Gaussian family were used to assess associations with antenatal exposures. Potential confounders were considered as well as the role of the child's size. RESULTS: Prior to pregnancy, 23% of mothers were overweight and another 17% obese. All women were screened for gestational diabetes, with 6% diagnosed. On average, women gained an estimated 14 kg during pregnancy. Gestational diabetes was positively associated with child insulin resistance. In addition, maternal pre-pregnancy body mass index (BMI) was associated with child insulin resistance in a non-linear manner: a positive, progressive association was observed until BMI of 30 kg/m² was reached, but not thereafter. Estimated gestational weight gain was not associated with child insulin resistance. These findings were not accounted for by size of the child at birth or at 9-10 years. CONCLUSIONS: Maternal body size prior to pregnancy is positively associated with increases in child insulin resistance, at least until the 'obese' category is reached. This is independent of gestational diabetes and not mediated by body size of the child, suggesting genetic and/or developmental programming origins.


Assuntos
Desenvolvimento Infantil , Diabetes Gestacional/fisiopatologia , Desenvolvimento Fetal , Resistência à Insulina , Fenômenos Fisiológicos da Nutrição Materna , Sobrepeso/fisiopatologia , Complicações na Gravidez/fisiopatologia , Adulto , Peso ao Nascer , Índice de Massa Corporal , Criança , Estudos de Coortes , Diabetes Gestacional/dietoterapia , Feminino , Humanos , Estudos Longitudinais , Sobrepeso/complicações , Gravidez , Estudos Prospectivos , Austrália do Sul , Aumento de Peso , Adulto Jovem
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