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1.
J Anim Ecol ; 92(9): 1771-1785, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37340858

RESUMO

The thermal sensitivity of early life stages can play a fundamental role in constraining species distributions. For egg-laying ectotherms, cool temperatures often extend development time and exacerbate developmental energy cost. Despite these costs, egg laying is still observed at high latitudes and altitudes. How embryos overcome the developmental constraints posed by cool climates is crucial knowledge for explaining the persistence of oviparous species in such environments and for understanding thermal adaptation more broadly. Here, we studied maternal investment and embryo energy use and allocation in wall lizards spanning altitudinal regions, as potential mechanisms that enable successful development to hatching in cool climates. Specifically, we compared population-level differences in (1) investment from mothers (egg mass, embryo retention and thyroid yolk hormone concentration), (2) embryo energy expenditure during development, and (3) embryo energy allocation from yolk towards tissue. We found evidence that energy expenditure was greater under cool compared with warm incubation temperatures. Females from relatively cool regions did not compensate for this energetic cost of development by producing larger eggs or increasing thyroid hormone concentration in yolk. Instead, embryos from the high-altitude region used less energy to complete development, that is, they developed faster without a concomitant increase in metabolic rate, compared with those from the low-altitude region. Embryos from high altitudes also allocated relatively more energy towards tissue production, hatching with lower residual yolk: tissue ratios than low-altitude region embryos. These results are consistent with local adaptation to cool climate and suggest that this is underpinned by mechanisms that regulate embryonic utilisation of yolk reserves and its allocation towards tissue, rather than shifts in maternal investment of yolk content or composition.


Assuntos
Clima , Temperatura Baixa , Feminino , Animais , Temperatura , Aclimatação , Embrião não Mamífero/metabolismo
2.
Proc Biol Sci ; 288(1951): 20210271, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-34034513

RESUMO

Emerging patterns suggest telomere dynamics and life history are fundamentally linked in endotherms through life-history traits that mediate the processes underlying telomere attrition. Unlike endotherms, ectotherms maintain the ability to lengthen somatic telomeres throughout life and the link between life-history strategies and ectotherm telomere dynamics is unknown. In a well-characterized model system (Niveoscincus ocellatus), we used long-term longitudinal data to study telomere dynamics across climatically divergent populations. We found longer telomeres in individuals from the cool highlands than those from the warm lowlands at birth and as adults. The key determinant of adult telomere length across populations was telomere length at birth, with population-specific effects of age and growth on adult telomere length. The reproductive effort had no proximate effect on telomere length in either population. Maternal factors influenced telomere length at birth in the warm lowlands but not the cool highlands. Our results demonstrate that life-history traits can have pervasive and context-dependent effects on telomere dynamics in ectotherms both within and between populations. We argue that these telomere dynamics may reflect the populations' different life histories, with the slow-growing cool highland population investing more into telomere lengthening compared to the earlier-maturing warm lowland population.


Assuntos
Lagartos , Telômero , Adulto , Animais , Humanos , Recém-Nascido , Lagartos/genética , Reprodução , Telômero/genética , Homeostase do Telômero , Encurtamento do Telômero
3.
Osteoporos Int ; 31(5): 1017-1018, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32232508

RESUMO

The original version of this article, published on 21 March 2019, unfortunately contained a mistake.

4.
Osteoporos Int ; 31(8): 1603-1605, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32533195

RESUMO

The original version of this article, published on 21 March 2019, unfortunately contains some typos in Figs. 2, 3, 4, and Supplemental Fig. 1. The corrected figures are given below.

5.
Osteoporos Int ; 31(7): 1299-1304, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32062687

RESUMO

This study expands on previous findings that hip fracture rates may no longer be declining. We found that age- and sex-adjusted fracture rates in the US plateaued or increased through mid-2017 in a population of commercially insured and Medicare Advantage health plan enrollees, in contrast to a decline from 2007 to 2013. INTRODUCTION: The purpose of this study was to evaluate fracture trends in US commercial and Medicare Advantage health plan members aged ≥ 50 years between 2007 and 2017. METHODS: Retrospective analysis of the Optum Research Database from January 1, 2007, to May 31, 2017. RESULTS: Of 1,841,263 patients identified with an index fracture, 930,690 were case-qualifying and included in this analysis. The overall age- and sex-adjusted fracture rate decreased from 14.67/1000 person-years (py) in 2007 to 11.79/1000 py in 2013, followed by a plateau for the next 3 years and then an increase to 12.50/1000 py in mid-2017. In females aged ≥ 65 years, fracture rates declined from 27.49/1000 py in 2007 to 22.08/1000 py in 2013, then increased to 24.92/1000 py in mid-2017. Likewise, fracture rates in males aged ≥ 65 years declined from 2007 (12.00/1000 py) to 2013 (10.72/1000 py), then increased to 12.04/1000 py in mid-2017. The age- and sex-adjusted fracture rates for most fracture sites declined from 2007 to 2013 by 3.7% per year (P = 0.310). CONCLUSIONS: Following a consistent decline in fracture rate from 2007 to 2013, trends from 2014 to 2017 indicate fracture rates are no longer declining and, for some fracture types, rates are rising.


Assuntos
Fraturas do Quadril , Fraturas por Osteoporose , Adolescente , Idoso , Feminino , Fraturas do Quadril/epidemiologia , Humanos , Incidência , Masculino , Programas de Assistência Gerenciada , Medicare , Fraturas por Osteoporose/epidemiologia , Estudos Retrospectivos , Estados Unidos/epidemiologia
6.
Osteoporos Int ; 30(7): 1465-1473, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30953114

RESUMO

This network meta-analysis assessed the efficacy of abaloparatide versus other treatment options to reduce the risk of fractures in women with postmenopausal osteoporosis. The analysis indicates that abaloparatide reduces the risk of fractures in women with postmenopausal osteoporosis versus placebo and compared with other treatment options. INTRODUCTION: This network meta-analysis (NMA) assessed the relative efficacy of abaloparatide versus other treatments to reduce the risk of fractures in women with postmenopausal osteoporosis (PMO). METHODS: PubMed®, Embase®, and the Cochrane Central Register of Controlled Trials were searched for randomized controlled trials published before December 20, 2017, that included women with PMO who were eligible to receive interventions for primary or secondary fracture prevention. The NMA was conducted by fracture site (vertebral [VF], nonvertebral [NVF], and wrist), with the relative risk (RR) of fracture versus placebo the main clinical endpoint. The NMA used fixed-effects and random-effects approaches. RESULTS: A total of 4978 articles were screened, of which 22 were included in the analysis. Compared with other treatments, abaloparatide demonstrated the greatest treatment effect relative to placebo in the VF network (RR = 0.13; 95% credible interval [CrI] 0.04-0.34), the NVF network (RR = 0.50; 95% CrI 0.28-0.85), and the wrist fracture network (RR = 0.39; CrI 0.15-0.90). Treatment ranking showed that abaloparatide had the highest estimated probability of preventing fractures in each of the networks (79% for VF, 70% for NVF, and 53% for wrist fracture) compared with other treatments. Individual networks demonstrated a good level of agreement with direct trial evidence and direct pair-wise comparisons. CONCLUSIONS: This NMA indicates that abaloparatide reduces the RR of VF, NVF, and wrist fracture in women with PMO with or without prior fracture versus placebo, compared with other treatment options. Limitations include that adverse events and drug costs were not considered, and that generalizability is limited to the trial populations and endpoints included in the NMA.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Osteoporose Pós-Menopausa/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Proteína Relacionada ao Hormônio Paratireóideo/uso terapêutico , Fraturas da Coluna Vertebral/prevenção & controle , Feminino , Fraturas do Quadril/prevenção & controle , Humanos , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Comportamento de Redução do Risco , Traumatismos do Punho/prevenção & controle
7.
Osteoporos Int ; 30(3): 667-673, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30635696

RESUMO

Early PINP changes correlate with 18-month lumbar spine BMD changes and the correlation was greater with abaloparatide versus teriparatide. The uncoupling index was similar between the two agents. INTRODUCTION: We evaluated the relationship between early PINP changes and subsequent changes in spine BMD following abaloparatide and teriparatide treatments. We also explored the use of an "uncoupling index" (UI), the balance between bone formation and bone resorption, which we hypothesised would be similar in response to these treatment groups. METHODS: Blood samples were taken for measurement of bone turnover markers (BTMs) s-PINP and s-CTX at baseline, 1, 3, 6, 12, and 18 months from 189 abaloparatide patients and 227 teriparatide patients randomly selected from all participants who completed the study. BMD was measured by DXA at baseline, 6, 12, and 18 months. Correlations were calculated between log ratio of BTMs from baseline to 3 months and percent change from baseline in BMD at 18 months. A UI was calculated using log transformation and subtraction of the standard deviate for s-CTX from the standard deviate for s-PINP for each patient. RESULTS: Early BTM changes were associated with subsequent BMD changes for both treatments. Pearson correlations for the log ratio of PINP over baseline at 3 months and BMD percent change from baseline at 18 months were larger (P < 0.0001) with abaloparatide (r = 0.561) than teriparatide (r = 0.198). The mean UI at 1 month was greater for abaloparatide versus teriparatide (1.743 and 1.493, respectively; P = 0.03) but was similar at 3 months or later time points. CONCLUSIONS: Early s-PINP changes correlate with percentage change in lumbar spine BMD 18 months after treatment with both abaloparatide and teriparatide, though the correlation with abaloparatide was greater. The UI was similar between abaloparatide and teriparatide suggesting that the balance between formation and resorption markers was similar.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Remodelação Óssea/efeitos dos fármacos , Osteoporose Pós-Menopausa/fisiopatologia , Proteína Relacionada ao Hormônio Paratireóideo/farmacologia , Teriparatida/farmacologia , Idoso , Biomarcadores/sangue , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Conservadores da Densidade Óssea/uso terapêutico , Remodelação Óssea/fisiologia , Colágeno Tipo I/sangue , Método Duplo-Cego , Feminino , Humanos , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/tratamento farmacológico , Proteína Relacionada ao Hormônio Paratireóideo/uso terapêutico , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pró-Colágeno/sangue , Teriparatida/uso terapêutico
8.
Osteoporos Int ; 30(6): 1187-1194, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30899994

RESUMO

PURPOSE: Wrist fractures are common, contribute significantly to morbidity in women with postmenopausal osteoporosis, and occur predominantly at the ultradistal radius, a site rich in trabecular bone. This exploratory analysis of the phase 3 ACTIVE study evaluated effects of abaloparatide versus placebo and teriparatide on forearm bone mineral density (BMD) and risk of wrist fracture. METHODS: Forearm BMD was measured by dual energy X-ray absorptiometry in a subset of 982 women from ACTIVE, evenly distributed across the three treatment groups. Wrist fractures were ascertained in the total cohort (N = 2463). RESULTS: After 18 months, ultradistal radius BMD changes from baseline were 2.25 percentage points greater for abaloparatide compared with placebo (95% confidence interval (CI) 1.38, 3.12, p < 0.001) and 1.54 percentage points greater for abaloparatide compared with teriparatide (95% CI 0.64, 2.45, p < 0.001). At 18 months, 1/3 radius BMD losses (versus baseline) were similar for abaloparatide compared with placebo (-0.42; 95% CI -1.03, 0.20; p = 0.19) but losses with teriparatide exceeded those of placebo (-1.66%; 95% CI -2.27, -1.06; p < 0.001). The decline with abaloparatide was less than that seen with teriparatide (group difference 1.22%; 95% CI 0.57, 1.87; p < 0.001). The radius BMD findings, at both ultradistal and 1/3 sites, are consistent with the numerically lower incidence of wrist fractures observed in women treated with abaloparatide compared with teriparatide (HR = 0.43; 95% CI 0.18, 1.03; p = 0.052) and placebo (HR = 0.49, 95% CI 0.20, 1.19, p = 0.11). CONCLUSIONS: Compared with teriparatide, abaloparatide increased BMD at the ultradistal radius (primarily trabecular bone) and decreased BMD to a lesser extent at the 1/3 radius (primarily cortical bone), likely contributing to the numerically lower wrist fracture incidence observed with abaloparatide.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Osteoporose Pós-Menopausa/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Proteína Relacionada ao Hormônio Paratireóideo/uso terapêutico , Traumatismos do Punho/prevenção & controle , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/fisiopatologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/fisiopatologia , Rádio (Anatomia)/fisiopatologia , Fraturas do Rádio/etiologia , Fraturas do Rádio/fisiopatologia , Fraturas do Rádio/prevenção & controle , Traumatismos do Punho/etiologia , Traumatismos do Punho/fisiopatologia
9.
Biol Lett ; 15(7): 20190151, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31288685

RESUMO

Large-scale tissue regeneration has potential consequences for telomere length through increases in cell division and changes in metabolism which increase the potential for oxidative stress damage to telomeres. The effects of regeneration on telomere dynamics have been studied in fish and marine invertebrates, but the literature is scarce for terrestrial species. We experimentally induced tail autotomy in a lizard ( Niveoscincus ocellatus) and assessed relative telomere length (RTL) in blood samples before and after partial tail regeneration while concurrently measuring reactive oxygen species (ROS) levels. The change in ROS levels was a significant explanatory variable for the change in RTL over the 60-day experiment. At the average value of ROS change, the mean RTL increased significantly in the control group (intact tails), but there was no such evidence in the regenerating group. By contrast, ROS levels decreased significantly in the regenerating group, but there was no such evidence in the control group. Combined, these results suggest that tail regeneration following autotomy involves a response to oxidative stress and this potentially comes at a cost to telomere repair. This change in telomere maintenance demonstrates a potential long-term cost of tail regeneration beyond the regrowth of tissue itself.


Assuntos
Lagartos , Telômero , Animais , Estresse Oxidativo , Espécies Reativas de Oxigênio , Regeneração , Cauda
10.
Oecologia ; 191(4): 767-776, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31620874

RESUMO

Telomere dynamics vary fundamentally between endothermic populations and species as a result of differences in life history, yet we know little about these patterns in ectotherms. In ectotherms, the relationships between climate, metabolism and life history suggest that telomere attrition should be higher at relatively high environmental temperatures compared to relatively low environmental temperatures, but these effects may vary between populations due to local adaptation. To address this hypothesis, we sampled reactive oxygen species (ROS) and telomere length of lizards from warm lowland and cool highland populations of a climatically widespread lizard species that we exposed to hot or cold basking treatments. The hot treatment increased relative telomere length compared to the cold treatment independent of climatic origin or ROS levels. Lizards from the cool highland region had lower ROS levels than those from the warm lowland region. Within the highland lizards, ROS increased more in the cold basking treatment than the hot basking treatment. These results are in the opposite direction to those predicted, suggesting that the relationships between temperature, metabolism, ROS and telomere dynamics are not straightforward. Future work incorporating detailed understanding of the thermal reaction norms of these and other linked traits is needed to fully understand these processes.


Assuntos
Lagartos , Telômero , Animais , Clima Frio , Temperatura Baixa , Temperatura
11.
Osteoporos Int ; 29(2): 323-328, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29167971

RESUMO

In a phase 2 trial of 222 postmenopausal women with osteoporosis aged 55 to 85 years randomized to one of three different doses of abaloparatide-SC, subcutaneous teriparatide, or placebo for 24 weeks, abaloparatide-SC resulted in improvements in skeletal microarchitecture as measured by the trabecular bone score. INTRODUCTION: Subcutaneous abaloparatide (abaloparatide-SC) increases total hip and lumbar spine bone mineral density and reduces vertebral and non-vertebral fractures. In this study, we analyzed the extent to which abaloparatide-SC improves skeletal microarchitecture, assessed indirectly by trabecular bone score (TBS). METHODS: This is a post hoc analysis of a phase 2 trial of 222 postmenopausal women with osteoporosis aged 55 to 85 years randomized to abaloparatide-SC (20, 40, or 80 µg), subcutaneous teriparatide (20 µg), or placebo for 24 weeks. TBS was measured from lumbar spine dual X-ray absorptiometry (DXA) images in 138 women for whom the DXA device was TBS software compatible. Assessments were made at baseline, 12 and 24 weeks. Between-group differences were assessed by generalized estimating equations adjusted for relevant baseline characteristics, and a pre-determined least significant change analysis was performed. RESULTS: After 24 weeks, TBS increased significantly by 2.27, 3.14, and 4.21% versus baseline in participants on 20, 40, and 80 µg abaloparatide-SC daily, respectively, and by 2.21% in those on teriparatide (p < 0.05 for each). The TBS in the placebo group declined by 1.08%. The TBS increase in each treatment group was significantly higher than placebo at 24 weeks (p < 0.0001 for each) after adjustment for age, BMI, and baseline TBS. A dose-response was observed at 24 weeks across the three doses of abaloparatide-SC and placebo (p = 0.02). The increase in TBS in the abaloparatide-SC 80 µg group was significantly greater than TPTD (p < 0.03). CONCLUSIONS: These results are consistent with an effect of abaloparatide-SC to improve lumbar spine skeletal microarchitecture, as assessed by TBS.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Densidade Óssea/efeitos dos fármacos , Osteoporose Pós-Menopausa/tratamento farmacológico , Proteína Relacionada ao Hormônio Paratireóideo/administração & dosagem , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Conservadores da Densidade Óssea/farmacologia , Conservadores da Densidade Óssea/uso terapêutico , Osso Esponjoso/efeitos dos fármacos , Osso Esponjoso/fisiopatologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Injeções Subcutâneas , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/fisiopatologia , Fraturas por Osteoporose/prevenção & controle , Proteína Relacionada ao Hormônio Paratireóideo/farmacologia , Proteína Relacionada ao Hormônio Paratireóideo/uso terapêutico , Teriparatida/uso terapêutico
12.
Osteoporos Int ; 29(8): 1747-1757, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29947869

RESUMO

The present study, drawn from a sample of the Icelandic population, quantified high immediate risk and utility loss of subsequent fracture after a sentinel fracture (at the hip, spine, distal forearm and humerus) that attenuated with time. INTRODUCTION: The risk of a subsequent osteoporotic fracture is particularly acute immediately after an index fracture and wanes progressively with time. The aim of this study was to quantify the risk and utility consequences of subsequent fracture after a sentinel fracture (at the hip, spine, distal forearm and humerus) with an emphasis on the time course of recurrent fracture. METHODS: The Reykjavik Study fracture registration, drawn from a sample of the Icelandic population (n = 18,872), recorded all fractures of the participants from their entry into the study until December 31, 2012. Medical records for the participants were manually examined and verified. First sentinel fractures were identified. Subsequent fractures, deaths, 10-year probability of fracture and cumulative disutility using multipliers derived from the International Costs and Utilities Related to Osteoporotic fractures Study (ICUROS) were examined as a function of time after fracture, age and sex. RESULTS: Over 10 years, subsequent fractures were sustained in 28% of 1498 individuals with a sentinel hip fracture. For other sentinel fractures, the proportion ranged from 35 to 38%. After each sentinel fracture, the risk of subsequent fracture was highest in the immediate post fracture interval and decreased markedly with time. Thus, amongst individuals who sustained a recurrent fracture, 31-45% did so within 1 year of the sentinel fracture. Hazard ratios for fracture recurrence (population relative risks) were accordingly highest immediately after the sentinel fracture (2.6-5.3, depending on the site of fracture) and fell progressively over 10 years (1.5-2.2). Population relative risks also decreased progressively with age. The utility loss during the first 10 years after a sentinel fracture varied by age (less with age) and sex (greater in women). In women at the age of 70 years, the mean utility loss due to fractures in the whole cohort was 0.081 whereas this was 12-fold greater in women with a sentinel hip fracture, and was increased 15-fold for spine fracture, 4-fold for forearm fracture and 8-fold for humeral fracture. CONCLUSION: High fracture risks and utility loss immediately after fracture suggest that treatment given as soon as possible after fracture would avoid a higher number of new fractures compared with treatment given later. This provides the rationale for very early intervention immediately after a sentinel fracture.


Assuntos
Fraturas por Osteoporose/epidemiologia , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Traumatismos do Antebraço/epidemiologia , Fraturas do Quadril/epidemiologia , Humanos , Fraturas do Úmero/epidemiologia , Islândia/epidemiologia , Masculino , Pessoa de Meia-Idade , Recidiva , Sistema de Registros , Medição de Risco/métodos , Distribuição por Sexo , Fraturas da Coluna Vertebral/epidemiologia , Fatores de Tempo
13.
J Anim Physiol Anim Nutr (Berl) ; 102(3): 670-678, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29427381

RESUMO

The effects on rumen kinetics after feed and water had been deprived for 72 hr were studied using four fistulated Bos indicus steers. The animals were assigned in a 2 × 4 crossover design with two treatments: feed and water ad libitum (control) and no feed and water for 72 hr (deprived) with four steers per treatment over two time periods. Feed and water deprivation caused decreases in the numbers of cellulolytic bacteria (1.4 vs. 0.4 cfu × 106 /ml; p = .001), live (23.7 vs. 0.8 × 109 /ml; p = .001), dead (12.7 vs. 0.5 × 109 /ml; p = .001) and total bacterial counts (36.4 vs. 1.4 × 109 /ml; p = .001) at day 0, compared with the control treatment. However, the deprived group had greater numbers of cellulolytic bacteria (2.7 vs. 50.1 cfu × 106 /ml; p = .001), live (18.3 vs. 42.2 × 109 /ml; p = .001), dead (6. 5 vs. 19.1 × 109 /ml; p = .001) and total bacterial counts (24.8 vs. 61.3 × 109 /ml; p = .001) from rumen fluid on day 4, compared with the control treatment. The numbers of protozoa in rumen fluid from the deprived group were less than (551.2 vs. 2.4 × 103 /ml; p = .001) the control group on day 0. However, the deprived treatment had fewer protozoa in rumen fluid than the control treatment on day 4 (p = .001) and day 9 (p = .001). Volatile fatty acids and in vitro gas production as functional measurements of rumen fluid followed the same trend as the bacterial and protozoa populations. These results indicate that feed and water deprivation would have a negative but transient effect on the rumen kinetics of Bos indicus steers.


Assuntos
Bovinos/fisiologia , Privação de Alimentos , Motilidade Gastrointestinal/fisiologia , Rúmen/fisiologia , Privação de Água , Animais , Estudos Cross-Over , Masculino
14.
Diabetes Obes Metab ; 13(11): 1036-46, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21682834

RESUMO

AIM: The purpose of this study was to evaluate if superior glycaemic control could be achieved with Avandamet® (rosiglitazone/metformin/AVM) compared with metformin (MET) monotherapy, and if glycaemic effects attained with AVM are durable over 18 months of treatment. Bone mineral density (BMD) and bone biomarkers were evaluated in a subgroup of patients. METHODS: This was a phase IV, randomized, double-blind, multi-centre study in 688, drug naÏve, male and female patients who had an established clinical diagnosis of type 2 diabetes mellitus (T2DM). Patients were randomized in a 1 : 1 ratio either to AVM or MET. RESULTS: As initial therapy in patients with T2DM, AVM was superior to MET in achieving statistically significant reductions in glycated haemoglobin (HbA1c) (p < 0.0001) and fasting plasma glucose (FPG) (p < 0.001), with more patients reaching recommended HbA1c and FPG targets for intensive glycaemic control. The glycaemic effects attained with AVM compared to MET monotherapy were durable over 18 months of treatment. In the bone substudy, AVM was associated with a significantly lower BMD in comparison with MET at week 80 in the lumbar spine and total hip (p < 0.0012 and p = 0.0005, respectively). Between-treatment differences were not statistically significant for distal one-third of radius BMD, femoral neck BMD or total BMD. CONCLUSION: Superior glycaemic control was achieved with AVM compared with MET monotherapy. The superior glycaemic effects were shown to be durable over 18 months of treatment. AVM was associated with a significantly reduced BMD in comparison with MET at week 80 in the lumbar spine and total hip.


Assuntos
Glicemia/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas/efeitos dos fármacos , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Tiazóis/uso terapêutico , Adolescente , Adulto , Idoso , Biomarcadores/metabolismo , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
15.
Nat Med ; 5(3): 309-13, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10086387

RESUMO

In principle, transplantation of mesenchymal progenitor cells would attenuate or possibly correct genetic disorders of bone, cartilage and muscle, but clinical support for this concept is lacking. Here we describe the initial results of allogeneic bone marrow transplantation in three children with osteogenesis imperfecta, a genetic disorder in which osteoblasts produce defective type I collagen, leading to osteopenia, multiple fractures, severe bony deformities and considerably shortened stature. Three months after osteoblast engraftment (1.5-2.0% donor cells), representative specimens of trabecular bone showed histologic changes indicative of new dense bone formation. All patients had increases in total body bone mineral content ranging from 21 to 29 grams (median, 28), compared with predicted values of 0 to 4 grams (median, 0) for healthy children with similar changes in weight. These improvements were associated with increases in growth velocity and reduced frequencies of bone fracture. Thus, allogeneic bone marrow transplantation can lead to engraftment of functional mesenchymal progenitor cells, indicating the feasibility of this strategy in the treatment of osteogenesis imperfecta and perhaps other mesenchymal stem cell disorders as well.


Assuntos
Células da Medula Óssea/citologia , Transplante de Medula Óssea , Mesoderma/citologia , Osteoblastos/citologia , Osteogênese Imperfeita/terapia , Células-Tronco/citologia , Densidade Óssea , Transplante de Medula Óssea/efeitos adversos , Pré-Escolar , Feminino , Células-Tronco Hematopoéticas/citologia , Humanos , Lactente , Masculino , Osteogênese/fisiologia
16.
Med Vet Entomol ; 25(1): 17-24, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20636479

RESUMO

Information on the daily activity patterns of tabanid flies is important in the development of strategies that decrease the risk of pathogens transmitted by them. In addition, this information is useful to maximize numbers of tabanids trapped during short-term studies and to target feeding behavior studies of certain tabanid species to their times of peak activity. The current study examined the effects of various meteorological factors on the daily activity patterns of common tropical species of tabanids in north Queensland. Each species studied responded differently to weather factors. Tabanus townsvilli Ricardo (Diptera: Tabanidae) was most active during late morning and early afternoon, whereas Pseudotabanus silvester (Bergroth) and Tabanus pallipennis Macquart were most active in the late afternoon. Tabanus dorsobimaculatus Macquart was most active in the morning and early afternoon. Data on daily activity patterns of tabanid flies indicates that in an area such as Townsville, North Queensland, where several species of tabanid are present concurrently in high numbers, the overlapping periods of high activity for these species indicate a high risk of pathogen transmission for most of the day (10.00-19.00 hours). Similarly, because each species responds differently to weather variables, only extreme weather conditions are likely to inhibit activity of all species. These data also indicate that for maximal results, trapping and feeding behavior studies should be tailored to the preferred activity period of the species under investigation.


Assuntos
Dípteros/fisiologia , Doenças dos Cavalos/parasitologia , Insetos Vetores/fisiologia , Animais , Comportamento Animal , Monitoramento Ambiental , Comportamento Alimentar , Doenças dos Cavalos/prevenção & controle , Doenças dos Cavalos/transmissão , Cavalos , Controle de Insetos , Queensland , Especificidade da Espécie , Tempo (Meteorologia)
17.
Infect Prev Pract ; 2(4): 100100, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34368728

RESUMO

BACKGROUND: Carbapenems are a family of end line antibiotics with increasing levels of resistance that are a cause for concern. AIM: To ascertain whether the CPE screening programme employed in an acute tertiary hospital is fit for purpose. METHOD: We outlined the current working algorithm employed using a universal screening programme over a 26-month screening period. Rectal swabs are cultured on arrival. Those with suspicious growth are further investigated using NG-Carba 5 lateral flow tests and Vitek 2.0 sensitivity cards. These practices were compared with NHS guidelines. FINDINGS & CONCLUSIONS: In all, 53 true positives were detected from 45 patients since the screening was implemented in early 2018 (46 OXA-48, 6 KPC, 1 NDM). As the rate of screening increased, the number of positive screens decreased over time. There were a lot of similarities between the HSE guidelines and the published NHS CPE toolkit. It was evident that there is no standard practice being employed across all hospitals. Comparing the MUH to national guidelines it appears to be quicker and more effective with universal screening in place at reducing the potential contacts and identifying carriers. Cost analysis indicates that the need to confirm all positive strains in a reference lab is costly, unnecessary and time consuming. There are adequate confirmatory tests available in-house for routine positive screens. It was concluded that infection prevention and control are key to identifying and controlling possible outbreaks in a hospital setting.

18.
Science ; 219(4583): 391-3, 1983 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-17815319

RESUMO

Handling of autotomized, thrashing and autotomized, exhausted tails of the lizard Scincella lateralis by mammals and snakes was tested to examine the function of postautotomy tail movement. Tail movement attracted a mammal's attack to the tail, permitting the lizard to escape and increased the time required for a snake to subdue a tail before swallowing it, increasing the lizard's escape time by 40 percent. Lactate concentrations of autotomized tails after movement were compared to those of intact tails after rest in S. lateralis, a species with a high rate of autotomized tail thrashing, and Anolis carolinensis, a species with a low rate of thrashing. Postautotomy movement increased tail lactate concentration in both species, but mean tail lactate concentration in S. lateralis was 60 percent higher than that in A. carolinensis, and a third higher than that reportedfor whole-body lactate content of the very mobile lizard Dipsosaurus dorsalis.

19.
Arch Osteoporos ; 14(1): 15, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30719589

RESUMO

We evaluated the efficacy of abaloparatide in women who were at increased risk for fracture, based on CHMP recommended risk thresholds, at the Abaloparatide Comparator Trial In Vertebral Endpoints (ACTIVE) study baseline. Among patients at high risk based on FRAX probabilities, 18 months of abaloparatide significantly decreased risk for all fracture endpoints compared with placebo. PURPOSE: Abaloparatide, a novel anabolic agent for the treatment of postmenopausal osteoporosis, significantly reduced the risk of vertebral and nonvertebral fractures in the ACTIVE study compared with placebo. In this post hoc analysis, we evaluated abaloparatide's efficacy in a subset of women in the study at an increased risk of fracture at baseline, based on the Committee for Medicinal Products for Human Use (CHMP) recommended risk thresholds for inclusion in clinical trials. METHODS: Women with a baseline 10-year risk of major osteoporotic fracture ≥ 10% or hip fracture ≥ 5%, assessed using the FRAX® tool (including femoral neck bone mineral density), were included in the analysis. The proportion with one or more events of new morphometric vertebral fractures was calculated. Event rates for nonvertebral, major osteoporotic, and all clinical fractures were estimated using Kaplan-Meier analysis. RESULTS: Following 18 months of treatment, abaloparatide significantly reduced incident vertebral fractures compared with placebo (relative risk reduction = 91%; 0.5% versus 5.6%; p < 0.001). Abaloparatide treatment was also associated with significantly fewer nonvertebral, major osteoporotic, and clinical fractures compared with placebo: 2.7% versus 5.8%, p = 0.036; 1.3% versus 6.0%, p < 0.001; and 3.5% versus 8.2%, p = 0.006, respectively. The effect of abaloparatide on major osteoporotic fractures (78% reduction) was significantly greater than that seen with teriparatide (23% reduction, p = 0.007). CONCLUSION: In a subset of postmenopausal women at increased risk of fracture as judged by CHMP guidance, abaloparatide significantly decreased the risk of all fracture endpoints compared with placebo.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Osteoporose Pós-Menopausa/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Proteína Relacionada ao Hormônio Paratireóideo/uso terapêutico , Idoso , Feminino , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/etiologia , Fraturas do Quadril/prevenção & controle , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/complicações , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Pós-Menopausa , Fatores de Risco , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/etiologia , Fraturas da Coluna Vertebral/prevenção & controle , Resultado do Tratamento
20.
Bone ; 120: 137-140, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30359763

RESUMO

BACKGROUND: Abaloparatide is a 34-amino acid peptide that selectively binds to the RG conformation of the parathyroid hormone receptor type 1. It was developed for the treatment of women with postmenopausal osteoporosis at high risk of fracture. In ACTIVE, an 18-month phase 3 study (NCT01343004), abaloparatide increased bone mineral density (BMD), decreased the risk of vertebral and nonvertebral fractures compared with placebo, and decreased the risk of major osteoporotic fractures compared with placebo and teriparatide. Here, we report a prospective, exploratory BMD responder analysis from ACTIVE. METHODS: Proportions of patients experiencing BMD gains from baseline of >0%, >3%, and >6% at the total hip, femoral neck, and lumbar spine at 6, 12, and 18 months of treatment were compared among the placebo, abaloparatide, and teriparatide groups in ACTIVE. Responders were defined prospectively as patients experiencing BMD gains at all 3 anatomic sites. RESULTS: At months 6, 12, and 18, there were significantly more >3% BMD responders in the abaloparatide group compared with placebo and teriparatide: month 6, 19.1% vs 0.9% for placebo and 6.5% for teriparatide; month 12, 33.2% vs 1.5% and 19.8%; month 18, 44.5% vs 1.9% and 32.0% (P < 0.001 for all comparisons of abaloparatide to placebo and to teriparatide). Findings were similar for the >0% and >6% responder thresholds. CONCLUSIONS: In postmenopausal women with osteoporosis, a significantly greater proportion of patients treated with abaloparatide experienced increases in BMD than did those treated with placebo or teriparatide.


Assuntos
Densidade Óssea/efeitos dos fármacos , Proteína Relacionada ao Hormônio Paratireóideo/farmacologia , Teriparatida/farmacologia , Idoso , Osso e Ossos/efeitos dos fármacos , Feminino , Humanos , Placebos
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