bluuebunny/crossref_metadata_2025_split huggingface dataset:
E-080 4D-Flow MRI quantifies hemodynamics in large and giant intracranial aneurysms
Authors: Ansari S , Schnell S , Vakil P , Hurley M , Bendok B , Batjer H , Carroll T , Carr J , Markl M 
Published: July 2012

PurposeUnruptured intracranial aneurysms (IA) are potentially life threatening conditions. Rupture risk based on specific data regarding interval growth or destabilization is lacking. We studied the feasibility of 4D-Flow MRI to analyze 3D flow patterns (vorticity) and aneurysm wall shear stress (WSS) in large and giant IAs.Materials and MethodsSeven patients (4F:3M, age=3.6±15.4 years) with large IAs (mean diameter=2.6±0.9 cm) were studied. IAs were located near the ICA bifurcation (n=5) or basilar artery (n=2) with saccular, spherical, or fusiform morphology. 4D flow MRI (3T TRIO & 1.5T Avanto, Siemens, Germany, voxel =0.99–1.8×0.78–1.46×1.2–1.4 mm, TE/TR=2.9–3.3/5.5–6 ms, temporal-res=44–48 ms, 3-directional velocity encoding with venc =70–80 cm/s) data were analyzed using Matlab-based tools and 3D blood flow visualization software. The WSS pattern along the aneurysm wall was calculated by cubic spline interpolation of the velocity gradient along the aneurysm contour as described previously. The vorticity defined asVort=abs(ζx,ζy,ζz) (with ζx=δw/δy –δv/δz, ζy=δu/δz–δw/δx, ζz=δv/δx–δu/δy andu,v,wbeing the velocity vector components2) was calculated within the plane transecting the aneurysm.Results3D spatial and 3-directional velocity encoding allowed for the 3D visualization of complex intracranial flow patterns. Flow patterns in the aneurysms could be classified in two morphological groups. Narrow high-flow channels in combination with large central low flow regions were identified in five saccular/spherical IAs. Slow flow with less defined flow channels were noted in two fusiform IAs. The distribution of WSS was significantly more heterogeneous and increased and vorticity in the plane through the IA center was significantly higher for saccular/spherical vs fusiform IAs (WSS=0.63N/m2±0.33 N/m2 vs 0.038 N/m2±0.016; Vorticity =0.073±0.028 vs 0.018±0.005; p<0.01).ConclusionOur feasibility study shows the potential of 4D flow MRI to identify differences in flow characteristics such as vorticity and WSS patterns in two IA morphology groups which may improve risk stratification and treatment planning.Competing interestsNone.Abstract E-080 Figure 1Abstract E-080 Figure 2
Facilitating chlamydia testing among young people: a randomised controlled trial in cyberspace
Authors: Kang Melissa , Rochford Arlie , Skinner Rachel , Mindel Adrian , Webb Marianne , Peat Jenny , Usherwood Tim 
Published: July 2012

ObjectivesChlamydia notifications have been rising in Australia for over a decade and are highest in young people. This study aimed to evaluate the impact of an internet-based intervention on chlamydia testing among young people 16–25 years.MethodsIn this randomised controlled trial, recruitment, data collection, study interventions and follow-up occurred entirely in cyberspace, facilitated by a website. Eligible participants were aged 16–25 years and resided in Australia. The intervention group received personalised emails inviting interaction about chlamydia testing, while the control group received regular impersonal emails. Primary outcome was self-reported chlamydia testing at 6-month follow-up; secondary outcomes were condom use and changes in knowledge and attitudes.Results704 young people completed baseline information, 40 were excluded and five withdrew prior to follow-up. The follow-up rate was 47.3% overall. In the intervention group, 40.6% (95% CI 30.7% to 51.1%) reported having had a chlamydia test at follow-up compared with 31.0% (95% CI 24.8% to 37.2%) in the control group (p=0.07). A per-protocol analysis found that those who engaged in email interaction were more likely to report chlamydia test uptake compared with those in the control group (52.5%, 95% CI 39.3 to 65.4% cf 31.0%, 95% CI 24.8% to 37.2%, p=0.002). There were no differences in secondary outcomes between groups.ConclusionsThis is the first randomised controlled trial undertaken in cyberspace to promote chlamydia testing. E-technology may be useful in promoting chlamydia testing and healthcare seeking behaviour in young people.
Factors associated with sexual debut during adolescence in the Republic of Korea
Authors: Lee Dong-Yun , Moon Jeong Min , Lee Im Soon , Suh Chang Suk , Choi DooSeok 
Published: July 2012

ObjectiveTo investigate the factors associated with sexual debut among Korean adolescents.MethodsBased on a 2008 cross-sectional nationwide online survey conducted in 75 238 Korean middle and high school students aged 12–18 years (39 278 boys and 35 960 girls), demographic profiles of the reproductive health and factors associated with sexual debut were analysed.ResultsThe proportion of adolescents who had heterosexual intercourse was 5.1%. The cumulative proportion of sexual debut at age 18 was 20%, and the median age was 17 years. Overall, 0.2% of girls reported past pregnancies, while 8.8% of sexually active girls had ever been pregnant. A proportion of girls who underwent an induced abortion was 89.5%. Up to half (46.0% for boys and 48.3% for girls) never resorted to contraception during coitus. After adjusting for covariates, attendance at general and technical high school, low school record, drinking alcohol, smoking, drug use, high economic status and not living with both parents were associated with the increased proportion of sexual debut in both genders. By contrast, internet use was associated with a reduced risk of adolescent sexual debut.ConclusionThis study demonstrates the factors associated with sexual debut among Korean adolescents. This information may be helpful for the prevention of unprotected sexual debut and subsequent teenage pregnancy in adolescents who are susceptible to initiating sexual intercourse.
Dietitian-coached management in combination with annual endocrinologist follow up improves global metabolic and cardiovascular health in diabetic participants after 24 months
Authors: Battista Marie-Claude , Labonté Mélissa , Ménard Julie , Jean-Denis Farrah , Houde Ghislaine , Ardilouze Jean-Luc , Perron Patrice 
Published: July 2012

This 24 month study evaluated the effect of dietitian coaching combined with minimal endocrinologist follow up on the glycemic control and cardiovascular risks of diabetic participants, compared with conventional endocrinologist follow up. Participants with type 1 or type 2 diabetes were assigned to either the control group with conventional endocrinologist follow up (C; n = 50) or the dietitian-coached group (DC; n = 51) with on-site diabetes self-management education every 3 months combined with annual endocrinologist followup. Over the 24 month intervention, weight (–0.7 vs. +2.1 kg; p = 0.04), BMI (+0.3 vs. +0.7 kg/m2; p = 0.009), and waist circumference (–1.3 vs. +2.4 cm; p = 0.01) significantly differed between the DC and control groups. HbA1Cdropped significantly in participants of the DC versus the control group (–0.6% vs.–0.3%; p = 0.04). This was accompanied by improved overall energy intake (–548 vs. –74 kcal/day; p = 0.04). However, no link associated glycemic control to nutrient intake or intensiveness of pharmacotherapy. Coaching by a dietitian improves glycemic control and reduces certain cardiovascular risk factors in diabetic subjects, demonstrating that a joint dietitian–endocrinologist model of care provides a convenient strategy for cardiovascular risk management in the diabetic population.
A scientific nutrition strategy improves time trial performance by ≈6% when compared with a self-chosen nutrition strategy in trained cyclists: a randomized cross-over study
Authors: Hottenrott Kuno , Hass Erik , Kraus Manon , Neumann Georg , Steiner Martin , Knechtle Beat 
Published: July 2012

We investigated whether an athlete’s self-chosen nutrition strategy (A), compared with a scientifically determined one (S), led to an improved endurance performance in a laboratory time trial after an endurance exercise. S consisted of about 1000 mL·h–1 fluid, in portions of 250 mL every 15 min, 0.5 g sodium·L–1, 60 g glucose·h–1, 30 g fructose·h–1, and 5 mg caffeine·kg body mass–1. Eighteen endurance-trained cyclists (16 male; 2 female) were tested using a randomized crossover-design at intervals of 2 weeks, following either A or S. After a warm-up, a maximal oxygen uptake test was performed. Following a 30-min break, a 2.5-h endurance exercise on a bicycle ergometer was carried out at 70% maximal oxygen uptake. After 5 min of rest, a time trial of 64.37 km (40 miles) was completed. The ingested nutrition was recorded every 15 min. In S, the athletes completed the time trial faster (128 vs. 136 min; p ≤ 0.001) and with a significantly higher power output (212 vs. 184 W; p ≤ 0.001). The intake of fluid, energy (carbohydrate-, mono-, and disaccharide), and sodium was significantly higher in S compared with A (p ≤ 0.001) during the endurance exercise. In the time trial, only sodium intake was significantly higher in S (p ≤ 0.001). We concluded that a time trial performance after a 2.5-h endurance exercise in a laboratory setting was significantly improved following a scientific nutrition strategy.
Two maximal isometric contractions attenuate the magnitude of eccentric exercise-induced muscle damage
Authors: Chen Hsin-Lian , Nosaka Kazunori , Pearce Alan J. , Chen Trevor C. 
Published: July 2012

This study investigated whether maximal voluntary isometric contractions (MVC-ISO) would attenuate the magnitude of eccentric exercise-induced muscle damage. Young untrained men were placed into one of the two experimental groups or one control group (n = 13 per group). Subjects in the experimental groups performed either two or 10 MVC-ISO of the elbow flexors at a long muscle length (20° flexion) 2 days prior to 30 maximal isokinetic eccentric contractions of the elbow flexors. Subjects in the control group performed the eccentric contractions without MVC-ISO. No significant changes in maximal voluntary concentric contraction peak torque, peak torque angle, range of motion, upper arm circumference, plasma creatine kinase (CK) activity and myoglobin concentration, muscle soreness, and ultrasound echo intensity were evident after MVC-ISO. Changes in the variables following eccentric contractions were smaller (P < 0.05) for the 2 MVC-ISO group (e.g., peak torque loss at 5 days after exercise, 23% ± 3%; peak CK activity, 1964 ± 452 IU·L–1; peak muscle soreness, 46 ± 4 mm) or the 10 MVC-ISO group (13% ± 3%, 877 ± 198 IU·L–1, 30 ± 4 mm) compared with the control (34% ± 4%, 6192 ± 1747 IU·L–1, 66 ± 5 mm). The 10 MVC-ISO group showed smaller (P < 0.05) changes in all variables following eccentric contractions compared with the 2 MVC-ISO group. Therefore, two MVC-ISO conferred potent protective effects against muscle damage, whereas greater protective effect was induced by 10 MVC-ISO, which can be used as a strategy to minimize muscle damage.
Training effects on peripheral muscle oxygenation and performance in children with congenital heart diseases
Authors: Moalla Wassim , Elloumi Mohamed , Chamari Karim , Dupont Grégory , Maingourd Yves , Tabka Zouhair , Ahmaidi Said 
Published: July 2012

We investigated the effect of training on peripheral muscular performance and oxygenation during exercise and recovery in children with congenital heart diseases (CHD). Eighteen patients with CHD aged 12 to 15 years were randomly assigned into either an individualized 12-week aerobic cycling training group (TG) or a control group (CG). Maximal voluntary contraction (MVC) and endurance at 50% MVC (time to exhaustion, Tlim) of the knee extensors were measured before and after training. During the 50% MVC exercise and recovery, near-infrared spectroscopy (NIRS) was used to assess the fall in muscle oxygenation, i.e., deoxygenation ([Formula: see text]) of the vastus lateralis, the mean rate of decrease in muscle oxygenation, the half time of recovery (T1/2R), and the recovery speed to maximal oxygenation (RS). There was no effect of time on any parameter in the CG. After training, significant improvements were observed in TG for MVC (101.6 ± 14.0 vs. 120.2 ± 19.4 N·m, p < 0.01) and Tlim (66.2 ± 22.6 vs. 86.0 ± 23.0 s, p< 0.01). Increased oxygenation (0.20 ± 0.13 vs. 0.15 ± 0.07 a.u., p < 0.01) and faster mean rate of decrease in muscle oxygenation were also shown after training in TG (1.22 ± 0.45 vs. 1.71 ± 0.78%·s–1, p < 0.001). Moreover, a shorter recovery time was observed in TG after training for T1/2R (27.2 ± 6.1 vs. 20.8 ± 4.2 s, p < 0.01) and RS (63.1 ± 18.4 vs. 50.3 ± 11.4 s, p < 0.01). A significant relationship between the change in [Formula: see text] and both MVC (r = 0.95, p < 0.001) and Tlim (r = 0.90, p < 0.001) in TG was observed. We concluded that exercise training improves peripheral muscular function by enhancing strength and endurance performance in children with CHD. This improvement was associated with increased oxygenation of peripheral muscles and faster recovery.
The effects of chronic exercise on the inflammatory cytokines interleukin-6 and tumor necrosis factor-α are different with age
Authors: Moon Min Kyong , Cho Bong Jun , Lee You Jin , Choi Sung Hee , Lim Soo , Park Kyong Soo , Park Young Joo , Jang Hak Chul 
Published: July 2012

Aging is associated with chronic low-grade inflammation, and interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) are key mediators of the inflammatory process. IL-6, especially muscle-derived IL-6, is expected to mediate the beneficial metabolic effects of exercise. There was no report that directly compares the effects of chronic endurance exercise on cytokine responses between old and young subjects in the same situation. Therefore, we compared the effects of endurance exercise on the expression of IL-6 and TNF-α in old and young rats. Young (3-month-old) and old (20-month-old) male Fisher rats were trained for 12 weeks on the treadmill. We measured serum TNF-α and IL-6 concentrations by enzyme-linked immunosorbent assay and examined mRNA expression of TNF-α and IL-6 in muscle, liver, and white adipose tissue using reverse transcription – polymerase chain reaction. We found that old rats had higher basal IL-6 levels in the liver, as well as in the serum and the muscle. After chronic endurance exercise, young rats exhibited significant decreases in serum TNF-α levels and hepatic IL-6 expression. However, old rats exhibited no significant changes in either serum or tissue cytokine levels after endurance exercise. These findings suggest that chronic endurance exercise could influence the inflammatory response of hepatic tissues, as well as muscle, and that the effects of chronic endurance exercise on inflammatory cytokine levels are different between old and young rats and an exercise program tailored for old subjects will be needed to obtain beneficial anti-inflammatory effects from exercise.
Predictors of bone mineral density in a convenience sample of young Caucasian adults living in southern Ontario
Authors: Chouinard Laura E. , Randall Simpson Janis , Buchholz Andrea C. 
Published: July 2012

Osteoporosis is a major public health concern in Canada and worldwide. Although much is known about bone health in older adults, little is known about bone health in young, healthy Canadian men and women. The objectives of this research were to describe bone mineral density (BMD) of young, healthy adults living in southern Ontario, Canada, and to identify predictors of BMD in this population. Two-hundred and fifty-eight Caucasian men and women aged 18–33 years completed health and physical activity questionnaires along with a calcium and vitamin D specific food frequency questionnaire. Height and mass were measured. BMD of the total hip, femoral neck, spine, and total body was measured using dual energy X-ray absorptiometry. Among men, body mass, weight-bearing physical activity, and calcium intake were significant predictors of BMD. Among women, body mass, calcium intake, and family history of osteoporosis significantly predicted log BMD. The predictors of BMD in young Canadian men and women identified in this study may inform the development of longitudinal studies designed to examine the influence of lifestyle factors on BMD in young adults.
Perilipin family (PLIN) proteins in human skeletal muscle: the effect of sex, obesity, and endurance training
Authors: Peters Sandra J. , Samjoo Imtiaz A. , Devries Michaela C. , Stevic Ivan , Robertshaw Holly A. , Tarnopolsky Mark A. 
Published: July 2012

Proteins that coat the lipid droplets (also known as PAT proteins or perilipin (PLIN) family proteins) have diverse functions that are not well elucidated in many tissues. In skeletal muscle, there is even less known about the functions or characteristics of these proteins or how they might change in response to perturbations that alter both intramyocellular lipid (IMCL) content and fat utilization and oxidation. Therefore, the purpose of this study was to examine the human muscle content and gene expression of the four skeletal muscle PLIN proteins in both lean and obese men and women and how this was changed following a 12-week endurance training protocol. PLIN2–PLIN5 proteins were all more abundant in women than in men (p = 0.037 and p < 0.0001, respectively), consistent with higher IMCL content observed in female skeletal muscle. PLIN5 (previously known as OXPAT) is of particular interest because it has previously been associated primarily with oxidative tissues that rely heavily on fat oxidation for energy production. Although PLIN5 was not different between lean and obese subjects, it was the only PLIN protein to increase in response to endurance training in both sexes. PLIN5 correlated with IMCL volume (p < 0.0001), but in general, the other PLIN proteins did not correlate well with IMCL volume, suggesting that the relationship between lipid accumulation and PLIN family protein content is not a simple one. Although more work is necessary, it is clear that PLIN5 likely plays an important role in IMCL accumulation and oxidation, both of which increase with endurance training in human skeletal muscle.
The Rho kinase inhibitor azaindole-1 has long-acting vasodilator activity in the pulmonary vascular bed of the intact chest rat
Authors: Pankey Edward A. , Byun Ryuk J. , Smith William B. , Bhartiya Manish , Bueno Franklin R. , Badejo Adeleke M. , Stasch Johannes-Peter , Murthy Subramanyam N. , Nossaman Bobby D. , Kadowitz Philip J. 
Published: July 2012

Responses to a selective azaindole-based Rho kinase (ROCK) inhibitor (azaindole-1) were investigated in the rat. Intravenous injections of azaindole-1 (10–300 µg/kg), produced small decreases in pulmonary arterial pressure and larger decreases in systemic arterial pressure without changing cardiac output. Responses to azaindole-1 were slow in onset and long in duration. When baseline pulmonary vascular tone was increased with U46619 or L-NAME, the decreases in pulmonary arterial pressure in response to the ROCK inhibitor were increased. The ROCK inhibitor attenuated the increase in pulmonary arterial pressure in response to ventilatory hypoxia. Azaindole-1 decreased pulmonary and systemic arterial pressures in rats with monocrotaline-induced pulmonary hypertension. These results show that azaindole-1 has significant vasodilator activity in the pulmonary and systemic vascular beds and that responses are larger, slower in onset, and longer in duration when compared with the prototypical agent fasudil. Azaindole-1 reversed hypoxic pulmonary vasoconstriction and decreased pulmonary and systemic arterial pressures in a similar manner in rats with monocrotaline-induced pulmonary hypertension. These data suggest that ROCK is involved in regulating baseline tone in the pulmonary and systemic vascular beds, and that ROCK inhibition will promote vasodilation when tone is increased by diverse stimuli including treatment with monocrotaline.
Postprandial but not fasting insulin resistance is an early identifier of dysmetabolism in overweight subjects
Authors: Patarrão Rita S. , Lautt W. Wayne , Afonso Ricardo A. , Ribeiro Rogério T. , Fernandes Ana B. , Boavida José M. , Macedo M. Paula 
Published: July 2012

The dynamic response to insulin is highly potentiated after meal ingestion, and this meal-induced insulin sensitization (MIS) in healthy subjects is dependent on cholinergic mechanisms. The main objective of this study was to test the hypothesis that the reduced response to insulin observed in moderately overweight subjects, in comparison with control lean subjects, is due to MIS impairment and not to a reduction in the direct hypoglycemic action of insulin. Both lean and overweight male subjects were recruited. Insulin sensitivity (IS) was assessed by the rapid insulin sensitivity test (RIST) performed after a 24 h fast, as well as after a standardized meal. Fasting glucose disposal was similar between lean and overweight subjects. Following the meal, glucose disposal increased more extensively in lean than overweight subjects. The insulin profiles, in both fasted and fed states, were superimposable, suggesting that the absence of a factor other than insulin is responsible for the decreased postprandial insulin sensitivity observed in overweight subjects. Our data suggest that in overweight subjects, MIS contribution is decreased, which is responsible for the postprandial impaired IS observed and is suggested to be the cause, not effect, of mild adiposity.
Understanding the in-vivo relevance of S-nitrosothiols in insulin action
Authors: Fernandes Ana B. , Guarino Maria P. , Macedo M. Paula 
Published: July 2012

Insulin sensitivity is maximal in the postprandial state, decreasing with a fasting period through a mechanism that is dependent on the integrity of the hepatic parasympathetic nerves/nitric oxide (NO) production and increased hepatic glutathione (GSH) levels. GSH and NO react to form S-nitrosoglutathione (GSNO), an S-nitrosothiol (RSNO) for which the in-vivo effects are still being determined. The goal of this study was to test the hypothesis that in-vivo administration of RSNOs, GSNO, or S-nitroso-N-acetylpenicillamine (SNAP) increases insulin sensitivity in fasted or fed-denervated animals, but not in fed animals, where full postprandial insulin sensitivity is achieved. Fasted, fed, or fed-denervated male Wistar rats were used as models for different insulin sensitivity conditions. The rapid insulin sensitivity test (RIST) was used to measure insulin-stimulated glucose disposal before and after drug administration (GSNO, SNAP, or 3-morpholinosydnonimine (SIN-1), intravenous (i.v.) or to the portal vein (i.p.v.)). Fast insulin sensitivity was not altered by administration of SIN-1 (neither i.v. nor i.p.v.). Intravenous infusion of RSNOs in fasted and fed hepatic denervated rats increased insulin sensitivity by 126.35% ± 35.43% and 82.7% ± 12.8%, respectively. In fed animals, RSNOs decreased insulin sensitivity indicating a negative feedback mechanism. These results suggest that RSNOs incremental effect on insulin sensitivity represent a promising therapeutical tool in insulin resistance states.