Characteristics of Maximum Performance of Pedaling Exercise in Recumbent and Supine Positions

To determine the characteristics of maximum pedaling performance in the recumbent and supine positions, maximum isokinetic leg muscle strength was measured in eight healthy male subjects during pedaling at three velocities (300°/s, 480°/s, and 660°/s), and maximum incremental tests were performed for each position. The maximum isokinetic muscle strength in the recumbent position was 210.0 ± 29.2 Nm at 300°/s, 158.4 ± 19.8 Nm at 480°/s, and 110.6 ± 13.2 at 660°/s. In contrast, the muscle strength in the supine position was 229.3 ± 36.7 Nm at 300°/s, 180. 7 ± 20.3 Nm at 480°/s, and 129.6 ± 14.0 Nm at 660°/s. Thus, the maximum isokinetic muscle strength showed significantly higher values in the supine position than in the recumbent position at all angular velocities. The knee and hip joint angles were measured at peak torque using a goniometer; the knee joint angle was not significantly different between both positions, whereas the hip joint angle was greater in the supine position than in the recumbent position (Supine position: 137.3 ± 9. 33 degree at 300°/s, 140.0 ± 11.13 degrees at 480°/s, and 141.0 ± 9.61 degrees at 660°/s. Recumbent position: 99.5 ± 12.21 degrees at 300°/s, 101.6 ± 12.29 degrees at 480°/s, and 105.8 ± 14.28 degrees at 660°/s). Peak oxygen uptake was higher in the recumbent position (50.3 ± 4.43 ml·kg^-1·min^-1) than in the supine position (48.7 ± 5.10 ml·kg^-1·min^-1). At maximum exertion, the heart rate and whole-body rate of perceived exertion (RPE) were unaffected by position, but leg muscle RPE was higher in the supine position (19.5 ± 0.53 than in the recumbent position (18.8 ± 0.71). These results suggest that the supine position is more suitable for muscle strength exertion than the recumbent position, and this may be due to different hip joint angles between the positions. On the contrary, the endurance capacity was higher in the recumbent position than in the supine position. Since leg muscle RPE was higher in the supine position than in the recumbent position, it was suggested that different burdens imposed on active muscles in both positions exerted an impact on the result of the endurance capacity.

Key points

• Isokinetic maximal peak torque measured in this study during pedaling showed higher values in the supine position than in the recumbent position at all angular velocities.
• Maximum oxygen uptake as evaluated by maximum incremental testing showed higher values in the recumbent position than in the supine position.
• No significant changes in the angle of peak torque for the knee joint or hip joint were observed in either the recumbent or supine position even at an increased angular velocity. These observations indicate the effectiveness of a cycle-type muscle strength assessment device for evaluating leg muscle strength.

Key words: Pedaling position, recumbent, supine, leg muscle strength, oxygen uptake     

TRANSPLANTED PERIPHERAL BLOOD STEM CELLS,MOBILIZED BY CHEMOTHERAPY ALONE,CAN INDUCE PERSISTENT HEMATOPOIESIS IN CHILDREN WITH ACUTE LEUKEMIA

Three patients with leukemia were transplanted with peripheral blood stem cells mobilized by in tensification or maintenance chemotherapy alone. They maintained persistent reconstituted hematopoiesis for at least 9 years. The experience provides evidence that long-term marrow repopulating cells can be mobilized into the blood to an adequate repopulating extent by chemotherapy alone.     

Endoscopic Evaluation of Adenoids: Reproducibility Analysis of Current Methods

Objectives

To investigate intra- and interexaminers'' reproducibility of usual adenoid hypertrophy assessment methods, according to nasofiberendoscopic examination.

Methods

Forty children of both sexes, ages ranging between 4 and 14 years, presenting with nasal obstruction and oral breathing suspected to be caused by adenoid hypertrophy, were enrolled in this study. Patients were evaluated by nasofiberendoscopy, and records were referred to and evaluated by two experienced otolaryngologists. Examiners analysed the records according to different evaluation methods; i.e., estimated, and measured percentage of choanal occlusion; as well as subjective and objective classificatory systems of adenoid hypertrophy.

Results

Data disclosed excellent intraexaminer reproducibility for both estimated and measured choanal occlusion. analysis revealed lower reproducibility rates of estimated in relation to measured choanal occlusion. Measured choanal occlusion also demonstrated less agreement among evaluations made through the right and left sides of the nasal cavity. Alternatively, intra- and interexaminers reliability analysis revealed higher agreement for subjective than objective classificatory system. Besides, subjective method demonstrated higher agreement than the objective classificatory system, when opposite sides were compared.

Conclusion

Our results suggest that measured is superior to estimated percentage of choanal occlusion, particularly if employed bilaterally, diminishing the lack of agreement between sides. When adenoid categorization is used instead, the authors recommend subjective rather than objective classificatory system of adenoid hypertrophy.     

Interleukin-17A expression in patients presenting with nasal polyposis

Sinonasal polyposis (SNP) is a chronic inflammatory pathology of the nasal/paranasal cavities which affects from 1%-4% of the population. Although polyps seem to be a manifestation of chronic inflammation of nasal/paranasal sinus mucosa in both allergic and non-allergic subjects, the pathogenesis of nasal polyposis remains unknown. Interleukin-17A (IL-17A) is a key inflammatory cytokine in many disorders. Little attention has been paid to the role of IL-17A in chronic inflammatory disorders.ObjectiveTo investigate the expression of IL-17A in the SNP and verify if this expression is a marker of good or bad prognosis.MethodProspective study with 25 patients presenting with SNP were subjected to the immunohistochemistry technique. After a skin prick test, all patients were divided into atopic and nonatopic groups, and asthmatic or non-asthmatic.ResultsThe IL-17A expression was observed in both atopic and nonatopic patients. The numbers of IL-17A positive cells were greater in nasal polyps of atopic patients than nonatopic (p = 0.0128).ConclusionThese results indicate that IL-17A may play an important role in the pathology of SNP. Considering the inflammatory properties of IL-17A, this study suggests that it could increase susceptibility to atopy and asthma.     

Evaluation of oxygen consumption in human vitrified and warmed pre-antral follicles after prolonged low temperatures

Purpose

The purpose of this study was to evaluate the effect of transportation at prolonged low temperatures on the survival of pre-antral follicles.

Methods

Ovarian tissue was removed from six women with gender identity disorder. Tissues were stored in an icebox at 4 °C for 6 or 18 h prior to vitrification. After warming, ovarian tissues were cultured for 24 h and follicle survival was assessed via a viability/cytotoxicity kit. Morphological features and oxygen consumption rate (OCR) were evaluated by scanning electrochemical microscopy (SECM).

Results

Survival rate of isolated primordial follicles was 95.7 and 100 %, and that of primary follicles was 91.7 and 81.8 % in the 6- and 18-h groups respectively. There was no difference in morphology between the 6- and 18-h storage groups. In comparison with OCR of vitrified-warmed follicles and OCR of 24-h culture after vitrified-warmed follicles, OCR of 24-h culture after vitrified-warmed primordial follicles was significantly higher in both 6-hour (0.02 ± 0.02 vs 0.07 ± 0.04, P < 0.05) and 18-h groups (0.02 ± 0.02 vs 0.11 ± 0.10, P < 0.05).

Conclusions

This strongly suggests that prolonged transportation of ovarian tissue at low temperatures is useful when there are no available local systems for fertility preservation.     

Adverse birth outcomes associated with maternal smoking and polymorphisms in the N-Nitrosamine-metabolizing enzyme genes NQO1 and CYP2E1

Maternal smoking during pregnancy can result in both pregnancy complications and reduced size of the fetus and neonate. Among women who smoke, genetic susceptibility to tobacco smoke also is a likely causative factor in adverse pregnancy outcomes. A prospective cohort study was conducted among 460 pregnant women who delivered live singletons in Sapporo, Japan, from 2002 to 2005. Multiple linear regression models were used to estimate associations of maternal smoking and polymorphisms in two genes encoding N-nitrosamine-metabolizing enzymes-NAD(P)H: quinone oxidoreductase 1 (NQO1) and cytochrome P-450 2E1 (CYP2E1)-with birth size. Among infants born to smokers with the NQO1 homozygous wild-type allele, birth weight, birth length, and birth head circumference were significantly reduced (p < 0.01 for each factor). For the homozygous wild-type CYP2E1 allele, birth weight was lower by an estimated 195 g (standard error, 55; p < 0.001) among smokers. These genotypes did not confer adverse effects among women who had never smoked or who quit smoking during the first trimester. The adverse effects of maternal smoking on infant birth size may be modified by maternal genetic polymorphisms in N-nitrosamine-metabolizing enzymes among Japanese subjects. These results may help in directing smoking cessation interventions during pregnancy, especially among susceptible women.     

Coronary heart disease risk factors in sub-Saharan Africa: studies in Tanzanian adolescents.

STUDY OBJECTIVE--To assess the level of cardiovascular risk factors in young people in sub-Saharan Africa living in rural and urban settings. DESIGN--Cross sectional survey of the population aged 15 to 19 years. SETTING--Eight rural Tanzanian villages in three regions, and two districts in Dar es Salaam. PARTICIPANTS--664 males and 803 females in rural villages and 85 males and 121 females in the city. Response rates for total population were 74% to 94% in the rural areas and 60% in the city. MEASUREMENTS AND RESULTS--Measurements included blood pressure, body mass index, serum lipids, and blood glucose concentrations (fasting and two hours after 75 g glucose). Blood pressure was slightly but significantly higher in young women than in young men (115/67 mmHg versus 113/65 mmHg) and increased significantly with age. Only 0.4% subjects had blood pressure greater than 140 and/or 90 mmHg. There were no urban-rural differences. Body mass index was higher in females (mean (SD) 20.3 (2.8) kg/m2) than males (18.5 (2.1)). Overweight was found in only 0.6% at age 15 years but 5.4% at age 19 years. Serum cholesterol concentrations were low at 3.5 mmol/l in males and 3.7 mmol/l in females. Only 7% had values above 5.2 mmol/l. The highest concentrations were found in the city and in Kilimanjaro, the most prosperous rural region. Serum triglycerides were 1.0 (0.5) mmol/l in males and 1.1 (0.5) mmol/l in females, and were highest in the city dwellers. Diabetes was rare (0.28% males, 0.12% females) but impaired glucose tolerance was present in 4.7% and 4.1% respectively. Drinking alcohol was equally prevalent in males and females, reaching 30% at age 19 years. Only 0.4% of females smoked compared with 7.3% of males. Smoking was commoner in rural areas that in the city. CONCLUSIONS--Several risk factors for cardiovascular disease were found in Tanzanian adolescents, but levels were much lower than in studies reported from developed nations. The challenge is to maintain these low levels as the population becomes more urbanised and more affluent.     

Study in Tanzania of impaired glucose tolerance. Methodological myth?

During a study of diabetes prevalence in six rural Tanzanian communities, a repeat oral glucose tolerance test (OGTT) was carried out in 514 subjects greater than or equal to 15 yr of age within 1 wk of an initial 75-g OGTT. In 498 subjects, blood glucose was measured 2 h after the glucose load on both occasions, and in 175 subjects, fasting blood glucose measurement was also repeated. Of the 498 subjects, 245 had normal glucose tolerance in the first test and were selected at random for further testing; 223 subjects had impaired glucose tolerance (IGT), and 30 had diabetic values. Diabetes and IGT were diagnosed on the basis of the 2-h blood glucose values. In the second test, 241 (98.4%) of the 245 subjects with normal tolerance continued in this category and 4 (1.6%) showed IGT. Of the 223 with IGT in the first test, 171 (76.2%) reverted to normal on the second test, 7 (3.1%) had diabetic values, and 45 (20.2%) persisted with IGT. Of the 30 subjects diagnosed as diabetic in the first test, 8 (26.7%) remained with diabetic values, 11 (36.7%) had IGT, and 11 (36.7%) were normal. Based on the second test, the population-prevalence rates of diabetes and IGT would have been 0.5 and 3.3% vs. 1 and 7.6% based on the first test. There was a significant downward trend in the mean 2-h blood glucose values in all three diagnostic groups. Regression toward the mean could not account for the downward shift in blood glucose values observed on retesting.(ABSTRACT TRUNCATED AT 250 WORDS)