990 research outputs found
The effect of high-intensity aerobic interval training on markers of systemic inflammation in sedentary populations
© 2017, Springer-Verlag Berlin Heidelberg. Purpose: This study examined the effects of high-intensity interval training (HIIT; 30 s sprint, 4–5 min passive recovery) and prolonged intermittent sprint training (PIST; 10 s sprint, 2–3 min moderate exercise) on the systemic inflammatory markers C-reactive protein (CRP) and tumor necrosis factor-α (TNF-α), aerobic capacity, and anthropometry in a middle-aged, sedentary population. Methods: Fifty-five sedentary adults (age 49.2 ± 6.1 years) were randomised into HIIT (n = 20), PIST (n = 21), or a sedentary control group (CTRL n = 14). HIIT and PIST performed three training sessions per week for 9 weeks on a cycle ergometer, matched for total high-intensity time, while CTRL continued normal sedentary behaviours. Pre- and post-intervention testing involved measures of anthropometry, peak oxygen consumption (VO2peak), and venous blood collection for analyses of CRP and TNF-α. Results: HIIT and PIST increased VO2peak compared to CTRL (+3.66 ± 2.23 and 3.74 ± 2.62 mL kg min−1). A group × time interaction (p = 0.042) and main effect of time (p = 0.026) were evident for waist girth, with only HIIT showing a significant reduction compared to CTRL (−2.1 ± 2.8 cm). TNF-α and CRP showed no group × time interaction or time effect (p > 0.05). Conclusions: In sedentary individuals, 9 weeks of HIIT or PIST were effective to improve aerobic capacity; however, only HIIT significantly reduced waist girth and WHR compared to CTRL. Markers of systemic inflammation remained unchanged across all groups. Accordingly, for inflammation and VO2peak, the distribution of sprints and the active or passive recovery periods are inconsequential provided that total duration of high-intensity efforts is similar
Effects of aerobic, strength or combined exercise on perceived appetite and appetite-related hormones in inactive middle-aged men
© 2017 Human Kinetics, Inc. Aerobic exercise (AE) and strength exercise (SE) are reported to induce discrete and specific appetite-related responses; however, the effect of combining AE and SE (i.e., combined exercise; CE) remains relatively unknown. Twelve inactive overweight men (age: 48 ± 5 y; BMI: 29.9 ± 1.9 kg·m2) completed four conditions in a random order: 1) nonexercise control (CON) (50 min seated rest); 2) AE (50 min cycling; 75% VO2peak); 3) SE (10 × 8 leg extensions; 75% 1RM); and 4) CE (50% SE + 50% AE). Perceived appetite, and appetiterelated peptides and metabolites were assessed before and up to 2 h postcondition (0P, 30P, 60P, 90P, 120P). Perceived appetite did not differ between trials (p < .05). Acylated ghrelin was lower at 0P in AE compared with CON (p = .039), while pancreatic polypeptide (PP) was elevated following AE compared with CON and CE. Glucose-dependent insulinotropic peptide (GIPtotal) was greater following all exercise conditions compared with CON, as was glucagon, although concentrations were generally highest in AE (p < .05). Glucose was acutely increased with SE and AE (p < .05), while insulin and C-peptide were higher after SE compared with all other conditions (p < .05). In inactive, middle-aged men AE, SE and CE each have their own distinct effects on circulating appetite-related peptides and metabolites. Despite these differential exercise-induced hormone responses, exercise mode appears to have little effect on perceived appetite compared with a resting control in this population
Serosurvey of Coxiella burnetii (Q fever) in Dromedary Camels (Camelus dromedarius) in Laikipia County, Kenya
Dromedary camels (Camelus dromedarius) are an important protein source for people in semi-arid and arid regions of Africa. In Kenya, camel populations have grown dramatically in the past few decades resulting in the potential for increased disease transmission between humans and camels. An estimated four million Kenyans drink unpasteurized camel milk, which poses a disease risk. We evaluated the seroprevalence of a significant zoonotic pathogen, Coxiella burnetii (Q fever), among 334 camels from nine herds in Laikipia County, Kenya. Serum testing revealed 18.6% positive seroprevalence of Coxiella burnetii (n = 344). Increasing camel age was positively associated with C. burnetii seroprevalence (OR = 5.36). Our study confirmed that camels living in Laikipia County, Kenya, have been exposed to the zoonotic pathogen, C. burnetii. Further research to evaluate the role of camels in disease transmission to other livestock, wildlife and humans in Kenya should be conducted
The Worldvolume Action of Kink Solitons in AdS Spacetime
A formalism is presented for computing the higher-order corrections to the
worldvolume action of co-dimension one solitons. By modifying its potential, an
explicit "kink" solution of a real scalar field in AdS spacetime is found. The
formalism is then applied to explicitly compute the kink worldvolume action to
quadratic order in two expansion parameters--associated with the hypersurface
fluctuation length and the radius of AdS spacetime respectively. Two
alternative methods are given for doing this. The results are expressed in
terms of the trace of the extrinsic curvature and the intrinsic scalar
curvature. In addition to conformal Galileon interactions, we find a
non-Galileon term which is never sub-dominant. This method can be extended to
any conformally flat bulk spacetime.Comment: 32 pages, 3 figures, typos corrected and additional comments adde
Interleukin-1 regulates multiple atherogenic mechanisms in response to fat feeding
Background: Atherosclerosis is an inflammatory process that develops in individuals with known risk factors that include hypertension and hyperlipidaemia, influenced by diet. However, the interplay between diet, inflammatory mechanisms and vascular risk factors requires further research. We hypothesised that interleukin-1 (IL-1) signaling in the vessel wall would raise arterial blood pressure and promote atheroma.
Methodology/Principal Findings: Apoe(-/-) and Apoe(-/-)/IL-1R1(-/-) mice were fed high fat diets for 8 weeks, and their blood pressure and atherosclerosis development measured. Apoe(-/-)/IL-R1(-/-) mice had a reduced blood pressure and significantly less atheroma than Apoe(-/-) mice. Selective loss of IL-1 signaling in the vessel wall by bone marrow transplantation also reduced plaque burden (p<0.05). This was associated with an IL-1 mediated loss of endothelium-dependent relaxation and an increase in vessel wall Nox 4. Inhibition of IL-1 restored endothelium-dependent vasodilatation and reduced levels of arterial oxidative stress.
Conclusions/Significance: The IL-1 cytokine system links atherogenic environmental stimuli with arterial inflammation, oxidative stress, increased blood pressure and atherosclerosis. This is the first demonstration that inhibition of a single cytokine can block the rise in blood pressure in response to an environmental stimulus. IL-1 inhibition may have profound beneficial effects on atherogenesis in man
The merger that led to the formation of the Milky Way's inner stellar halo and thick disk
The assembly process of our Galaxy can be retrieved using the motions and
chemistry of individual stars. Chemo-dynamical studies of the nearby halo have
long hinted at the presence of multiple components such as streams, clumps,
duality and correlations between the stars' chemical abundances and orbital
parameters. More recently, the analysis of two large stellar surveys have
revealed the presence of a well-populated chemical elemental abundance
sequence, of two distinct sequences in the colour-magnitude diagram, and of a
prominent slightly retrograde kinematic structure all in the nearby halo, which
may trace an important accretion event experienced by the Galaxy. Here report
an analysis of the kinematics, chemistry, age and spatial distribution of stars
in a relatively large volume around the Sun that are mainly linked to two major
Galactic components, the thick disk and the stellar halo. We demonstrate that
the inner halo is dominated by debris from an object which at infall was
slightly more massive than the Small Magellanic Cloud, and which we refer to as
Gaia-Enceladus. The stars originating in Gaia-Enceladus cover nearly the full
sky, their motions reveal the presence of streams and slightly retrograde and
elongated trajectories. Hundreds of RR Lyrae stars and thirteen globular
clusters following a consistent age-metallicity relation can be associated to
Gaia-Enceladus on the basis of their orbits. With an estimated 4:1 mass-ratio,
the merger with Gaia-Enceladus must have led to the dynamical heating of the
precursor of the Galactic thick disk and therefore contributed to the formation
of this component approximately 10 Gyr ago. These findings are in line with
simulations of galaxy formation, which predict that the inner stellar halo
should be dominated by debris from just a few massive progenitors.Comment: 19 pages, 8 figures. Published in Nature in the issue of Nov. 1st,
2018. This is the authors' version before final edit
Mode of Delivery and Asthma at School Age in 9 European Birth Cohorts
Evidence on the association between mode of delivery and asthma at school age is inconclusive. We assessed the associations between specific modes of delivery and asthma in children from 9 European birth cohorts that enrolled participants between 1996 and 2006. Cohort-specific crude and adjusted risk ratios for asthma at ages 5–9 years were calculated using Poisson regression models and pooled. A sensitivity analysis was carried out in children born at term to reduce confounding due to perinatal factors. The study included 67,613 participants. Cohortspecific rates of cesarean delivery varied from 9.4% to 37.5%. Cesarean delivery, as opposed to vaginal delivery, was associated with an increased risk of asthma (adjusted risk ratio (aRR) = 1.22, 95% confidence interval (CI): 1.02, 1.46). Compared with spontaneous vaginal delivery, the adjusted risk ratio was 1.33 (95% CI: 1.02, 1.75) for elective cesarean delivery, 1.07 (95% CI: 0.94, 1.22) for emergency cesarean delivery, and 0.97 (95% CI: 0.84, 1.12) for operative vaginal delivery. In children born at term, the associations were strengthened only for elective cesarean delivery (aRR = 1.49, 95% CI: 1.13, 1.97). The large sample size allowed analysis of the associations between specific modes of delivery and asthma at school age. The increased risk of asthma associated with elective cesarean delivery, especially among children born at term, is relevant in counteracting the increasing use of this procedure, which is often performed without a clear medical indication.This work was supported by the European Community’s Seventh Framework Programme (FP7/2009–2013) under a grant agreement (grant 241604) and by the University of Turin and the San Paolo Foundation (Turin, Italy). Data collection was funded and the study teams of all participating birth cohorts were supported by local and/or national research organizations
Editorial Board
Source at http://dx.doi.org/10.1186/s12888-017-1345-8 Background: The duration of untreated psychosis is determined by both patient and service related factors.
Few studies have considered the geographical accessibility of services in relation to treatment delay in early
psychosis. To address this, we investigated whether treatment delay is co-determined by straight-line distance
to hospital based specialist services in a mainly rural mental health context.
Methods: A naturalistic cross-sectional study was conducted among a sample of recent onset psychosis patients
in northern Norway (n = 62). Data on patient and service related determinants were analysed.
Results: Half of the cohort had a treatment delay longer than 4.5 months. In a binary logistic regression model,
straight-line distance was found to make an independent contribution to delay in which we controlled for other
known risk factors.
Conclusions: The determinants of treatment delay are complex. This study adds to previous studies on treatment
delay by showing that the spatial location of services also makes an independent contribution. In addition, it may
be that insidious onset is a more important factor in treatment delay in remote areas, as the logistical implications of
specialist referral are much greater than for urban dwellers. The threshold for making a diagnosis in a remote location
may therefore be higher. Strategies to reduce the duration of untreated psychosis in rural areas would benefit from
improving appropriate referral by crisis services, and the detection of insidious onset of psychosis in community based
specialist services
Custom-designed orthopedic implants evaluated using finite element analysis of patient-specific computed tomography data: femoral-component case study
<p>Abstract</p> <p>Background</p> <p>Conventional knee and hip implant systems have been in use for many years with good success. However, the custom design of implant components based on patient-specific anatomy has been attempted to overcome existing shortcomings of current designs. The longevity of cementless implant components is highly dependent on the initial fit between the bone surface and the implant. The bone-implant interface design has historically been limited by the surgical tools and cutting guides available; and the cost of fabricating custom-designed implant components has been prohibitive.</p> <p>Methods</p> <p>This paper describes an approach where the custom design is based on a Computed Tomography scan of the patient's joint. The proposed design will customize both the articulating surface and the bone-implant interface to address the most common problems found with conventional knee-implant components. Finite Element Analysis is used to evaluate and compare the proposed design of a custom femoral component with a conventional design.</p> <p>Results</p> <p>The proposed design shows a more even stress distribution on the bone-implant interface surface, which will reduce the uneven bone remodeling that can lead to premature loosening.</p> <p>Conclusion</p> <p>The proposed custom femoral component design has the following advantages compared with a conventional femoral component. (i) Since the articulating surface closely mimics the shape of the distal femur, there is no need for resurfacing of the patella or gait change. (ii) Owing to the resulting stress distribution, bone remodeling is even and the risk of premature loosening might be reduced. (iii) Because the bone-implant interface can accommodate anatomical abnormalities at the distal femur, the need for surgical interventions and fitting of filler components is reduced. (iv) Given that the bone-implant interface is customized, about 40% less bone must be removed. The primary disadvantages are the time and cost required for the design and the possible need for a surgical robot to perform the bone resection. Some of these disadvantages may be eliminated by the use of rapid prototyping technologies, especially the use of Electron Beam Melting technology for quick and economical fabrication of custom implant components.</p
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