Comparative Analysis of Maximal Aerobic Capacity and Sprint-Related Physical Fitness in Keirin Cyclists

PURPOSE This study aimed to compare body composition, physical fitness, maximum muscle strength, and blood lactate concentration according to the level of aerobic capacity in Keirin cyclists. METHODS Forty-four Keirin cyclists participated in this study and were divided into three groups: the top 20% VO2max group (TG, n=9), the middle 20% VO2max group (MG, n=9), and the low 20% VO2max group (LG, n=9). The study measured body composition, physical fitness, maximum muscle strength, and blood lactate concentration in Keirin cyclists. Differences between groups were determined using one-way ANOVA analysis. RESULTS Body weight, percentage of body fat, and body mass index were significantly higher in the LG than in the TG and MG. The vertical jump and maximum muscle strength were significantly higher in the TG and MG than in the LG. Additionally, blood lactate concentrations immediately after exhaustive exercise and during the 5-minute recovery periods were higher in the LG than in the TG and MG. Moreover, the time to exhaustion, HRmax and maximum power were the highest in the TG. CONCLUSIONS Our findings suggest new information that levels of aerobic capacity in male Keirin cyclists might be a crucial predictor of cycling performance and recovery ability

Effect of Different Resistance Training Structures on Basic Physical Fitness and Isokinetic Muscular Contraction

PURPOSE This study aimed to investigate the effects of different resistance training structures on basic physical fitness, 1-repetition maximum (1RM), and isokinetic shoulder and knee muscle functions in male college students. METHODS Forty college students were divided into four groups: control group (CG, n=10), compound set training group (CSG, n=10), pyramid set training group (PSG, n=10), and superset training group (SSG, n=10). Excluding CG, each group performed a different resistance exercise method at an intensity of 60~80% 1RM for 60~90 min, three times a week for eight weeks. To compare the effects of resistance training structures, we confirmed body composition, basic physical fitness, 1RM, as well as isokinetic shoulder and knee functions. RESULTS Results indicated that the PSG exhibited the most significant improvement in relative peak torque in isokinetic shoulder and knee testing compared to the other groups. Additionally, all exercise groups positively affected back strength, 40m sprint, and 1RM compared to the CG, although no significant differences were observed among exercise groups. CONCLUSIONS The findings suggest scientific evidence supporting the effectiveness of pyramidal resistance training in improving isokinetic shoulder and knee muscle functions in male college students

Effect of two different exercises on balance, pain and ankle motor function in male college students with chronic ankle instability

Strength and proprioceptive exercise are known to be representative exercise methods used in patients with chronic ankle instability (CAI) and they are effective in restoring ankle stability and body balance, which gets reduced by repetitive ankle sprains. But, there is a lack of data comparing the effects of strengthening or proprioceptive exercise rehabilitation program for CAI patients. The purpose of this study is to investigate the effect of a 4-week exercise program on ankle range of motion (ROM), static/dynamic balance, and drop landing in college students with CAI. The subjects of this study were 21 male college students who had the Cumberland ankle instability tool (CAIT) questionnaire scores of 24 or less, and they were divided into three groups; the non-treated group (NTG), the traditional strength exercise group (SEG) and the proprioceptive exercise group (PEG). The exercise rehabilitation program was applied 3 times a week for 4 weeks. To examine the difference between groups, CAIT, visual analogue scale (VAS), body composition, ankle ROM, one-leg standing with eyes closed and Y-balance test (YBT) as well as center of pressure (COP) 95% confidence ellipse area during drop landing were measured before and after the exercise intervention. CAIT scores and static balance were significantly increased in the PEG compared to the NTG and the SEG, and ankle dorsiflexion ROM and Y-balance were significantly increased in the SEG and the PEG compared to the NTG. In addition, pain, ankle inversion ROM, and COP 95% confidence ellipse area were significantly reduced in the SEG and the PEG compared to the NTG. The proprioceptive exercise program is thought to be effective therapeutic approach on improving the symptoms of CAI patients

Evaluation of combinatorial cis-regulatory elements for stable gene expression in chicken cells

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background: Recent successes in biotechnological application of birds are based on their unique physiological traits such as unlimited manipulability onto developing embryos and simple protein constituents of the eggs. However it is not likely that target protein is produced as kinetically expected because various factors affect target gene expression. Although there have been various attempts to minimize the silencing of transgenes, a generalized study that uses multiple cis-acting elements in chicken has not been made. The aim of the present study was to analyze whether various cis-acting elements can help to sustain transgene expression in chicken fibroblasts. Results: We investigated the optimal transcriptional regulatory elements for enhancing stable transgene expression in chicken cells. We generated eight constructs that encode enhanced green fluorescent protein (eGFP) driven by either CMV or CAG promoters (including the control), containing three types of key regulatory elements: a chicken lysozyme matrix attachment region (cMAR), 5′-DNase I-hypersensitive sites 4 (cHS4), and the woodchuck hepatitis virus posttranscriptional regulatory element (WPRE). Then we transformed immortalized chicken embryonic fibroblasts with these constructs by electroporation, and after cells were expanded under G418 selection, analyzed mRNA levels and mean fluorescence intensity (MFI) by quantitative real-time PCR and flow cytometry, respectively. We found that the copy number of each construct significantly decreased as the size of the construct increased (R2 = 0.701). A significant model effect was found in the expression level among various constructs in both mRNA and protein (P < 0.0001). Transcription with the CAG promoter was 1.6-fold higher than the CMV promoter (P = 0.027) and the level of eGFP expression activity in cMAR- or cHS4-flanked constructs increased by two- to three-fold compared to the control CMV or CAG promoter constructs. In addition, flow cytometry analysis showed that constructs having cis-acting elements decreased the level of gene silencing as well as the coefficient of variance of eGFP-expressing cells (P < 0.0001). Conclusions: Our current data show that an optimal combination of cis-acting elements and promoters/enhancers for sustaining gene expression in chicken cells is suggested. These results provide important information for avian transgenesis and gene function studies in poultry

Long-term balloon indwelling technique for the treatment of single benign biliary stricture

We aimed to evaluate the feasibility and safety of long-term balloon indwelling technique for the treatment of single benign biliary stricture. Five patients with single benign biliary stricture were included from December 2014 to November 2016. The patients were three men and two women with a mean age of 50 years (range, 30–65 years). A balloon catheter was inserted into the drainage catheter and emerged through the side hole of the catheter so that the balloon and drainage catheters could be placed together at the stricture site. Follow-up fluoroscopic examination was performed at least once every 2 weeks to evaluate the adequacy of expansion and location of the balloon. The balloon was reinflated at each session, and then removed after an approximately two-month indwelling period. The catheters used were 10–16 French and the diameter of indwelling balloons were 4–8 mm. The primary technical and clinical success rates were 100%. Maintenance of the balloon location was achieved in 25 of 26 follow-up fluoroscopic examinations (mean, 5.2 times per patient) with a rate of 96.1%. The mean follow-up period after successful removal of the balloon was 542.2 days (range, 93–1042 days), and there were no recurrences in the five cases. The long-term balloon indwelling technique is a good way to induce maximal dilatation at the stricture site without large diameter skin and subcutaneous tract dilatation and can be successfully used for single benign biliary stricture

Superficial Endobronchial Lung Cancer: Radiologic-Pathologic Correlation

Objective: To analyze the plain chest radiographic and CT findings of superficial endobronchial lung cancer and to correlate these with the findings of histopathology. Materials and Methods: This study involved 19 consecutive patients with pathologically proven lung cancer confined to the bronchial wall. Chest radiographs and CT scans were reviewed for the presence of parenchymal abnormalities, endobronchial nodules, bronchial obstruction, and bronchial wall thickening and stenosis. The CT and histopathologic findings were compared. Results: Sixteen of the 19 patients had abnormal chest radiographic findings, while in 15 (79%), CT revealed bronchial abnormalities: an endobronchial nodule in seven, bronchial obstruction in five, and bronchial wall thickening and stenosis in three. Histopathologically, the lesions appeared as endobronchial nodules in 11 patients, irregular thickening of the bronchial wall in six, elevated mucosa in one, and carcinoma in situ in one. Conclusion: CT helps detect superficial endobronchial lung cancer in 79 % of these patients, though there is some disagreement between the CT findings and the pathologic pattern of bronchial lesions. Although nonspecific, findings of bronchial obstruction or bronchial wall thickening and stenosis should not be overlooked, and if clinically necessary, bronchoscopy should be performed. Index terms: Lung, radiograph

Differentiation of Recently Infarcted Myocardium from Chronic Myocardial Scar: The Value of Contrast-Enhanced SSFP-Based Cine MR Imaging

The purpose of this study is to demonstrate whether the signal intensity (SI) of myocardial infarction (MI) on contrast enhanced (CE)-cine MRI is useful for differentiating recently infarcted myocardium from chronic scar. This study included 24 patients with acute MI (36-84 years, mean age: 57) and 19 patients with chronic MI (44-80 years, mean age: 64). The diagnosis of acute MI was based on the presence of typical symptoms, i.e. elevation of the cardiac enzymes and the absence of any remote infarction history. The diagnosis of chronic MI was based on a history of MI or coronary artery disease of more than one month duration and on the absence of any recent MI within the previous six months. Retrospectively, the ECG-gated breath-hold cine imaging was performed in the short axis plane using a segmented, balanced, turbo-field, echo-pulse sequence two minutes after the administration of Gd-DTPA at a dose of 0.2 mmol/kg body weight. Delayed contrast-enhanced MRI (DCE MRI) in the same plane was performed 10 to 15 minutes after contrast administration, and this was served as the gold standard of reference. The SI of the infarcted myocardium on the CE-cine MRI was compared with that of the normal myocardium on the same image. The area of abnormal SI on the CE-cine MRI was compared with the area of hyperenhancement on the DCE MRI. The area of high SI on the CE-cine MRI was detected in 23 of 24 patients with acute MI (10 with homogenous high SI, 13 high SI with subendocardial low SI, and one with iso SI). The area of high SI on the CE-cine MRI was larger than that seen on the DCE MRI (p < 0.05). In contrast, the areas of chronic MI were seen as iso-SI with thin subendocardial low SI on the CE-cine MR in all the chronic MI patients. The presence of high SI on both the CE-cine MRI and the DCE MRI is more sensitive (95.8%) for determining the age of a MI than the presence of myocardial thinning (66.7%). This study showed the different SI patterns between recently infarcted myocardium and chronic scar on the CE-cine MRI. CE-cine MRI is thought to be quite useful for determining the age of myocardial infarction, in addition to its utility for assessing myocardial contractility