Interference by adrenaline with chondrogenic differentiation through suppression of gene transactivation mediated by Sox9 family members

In contrast to osteoblasts, little attention has been paid to the functional expression of adrenergic signaling machineries in chondrocytes. Expression of mRNA was for the first time demonstrated for different adrenergic receptor (AdR) subtypes in chondrogenic ATDC5 cells and mouse metatarsals isolated before vascularization in culture, but not for other molecules related to adrenergic signaling. In neonatal mouse tibial sections, β₂AdR and α_2aAdR mRNA expression was found in chondrocytes at different developmental stages by in situ hybridization. Exposure to adrenaline significantly suppressed expression of several maturation markers through the cAMP/protein kinase A pathway activated by β₂AdR without affecting cellular proliferation in both cultured ATDC5 cells and metatarsals. Adrenaline also significantly inhibited gene transactivation by sry-type HMG box 9 (Sox9) family members essential for chondrogenic differentiation in a manner prevented by the general βAdR antagonist propranolol, with a concomitant significant decrease in the levels of Sox6 mRNA and corresponding protein, in ATDC5 cells and primary cultured mouse costal chondrocytes. Systemic administration of propranolol significantly promoted the increased expression of mRNA for collagen I and collagen X, but not for collagen II, in callus of fractured femur in mice. These results suggest that adrenaline may interfere with chondrogenic differentiation through downregulation of Sox6 expression for subsequent suppression of gene transactivation mediated by Sox9 family members after activation of β₂AdR expressed by chondrocytes.     

Possible promotion of neuronal differentiation in fetal rat brain neural progenitor cells after sustained exposure to static magnetism

We have previously shown significant potentiation of Ca²⁺ influx mediated by N‐methyl‐D ‐aspartate receptors, along with decreased microtubules‐associated protein‐2 (MAP2) expression, in hippocampal neurons cultured under static magnetism without cell death. In this study, we investigated the effects of static magnetism on the functionality of neural progenitor cells endowed to proliferate for self‐replication and differentiate into neuronal, astroglial, and oligodendroglial lineages. Neural progenitor cells were isolated from embryonic rat neocortex and hippocampus, followed by culture under static magnetism at 100 mT and subsequent determination of the number of cells immunoreactive for a marker protein of particular progeny lineages. Static magnetism not only significantly decreased proliferation of neural progenitor cells without affecting cell viability, but also promoted differentiation into cells immunoreactive for MAP2 with a concomitant decrease in that for an astroglial marker, irrespective of the presence of differentiation inducers. In neural progenitors cultured under static magnetism, a significant increase was seen in mRNA expression of several activator‐type proneural genes, such as Mash1, Math1, and Math3, together with decreased mRNA expression of the repressor type Hes5. These results suggest that sustained static magnetism could suppress proliferation for self‐renewal and facilitate differentiation into neurons through promoted expression of activator‐type proneural genes by progenitor cells in fetal rat brain. © 2009 Wiley‐Liss, Inc.     

Relationship of body composition to body-fatness estimation in Japanese university students

OBJECTIVE: To examine the relationship between self-estimated whole body size and fatness and whole body and regional composition, and the relationship between self-estimated whole body fatness and self-estimated regional fatness in Japanese university students. RESEARCH METHODS AND PROCEDURES: This was a cross-sectional study using Japanese university students (110 men and 79 women). The percentage of body fat, fat mass (FM), and fat-free mass (FFM) were measured by underwater weighing and used as body composition variables. Subcutaneous fat thicknesses were determined at seven sites by ultrasonography to estimate regional body composition, and six circumferences and four breadths to estimate regional size. Relative body size and fatness were self-estimated using a questionnaire. RESULTS: Only women tended to estimate themselves as being fatter than they actually were. Self-estimated body fatness moderately correlated with the percentage of body fat (men, r = 0.41; women, r = 0.40) FM (men, r = 0.50; women, r = 0.51), and body mass index (r = 0.56 for men and 0.56 for women). After adjusting for the percentages of body fat and FM, self-estimated fatness correlated with body mass index (r = 0.31 for men and r = 0.37 for women). Among self-estimated regional fatness, self-estimated abdominal fatness had the strongest correlation with self-estimated whole body fatness in both genders. DISCUSSION: The low correlation between estimated and actual body fatness in both genders indicates that Japanese university students, especially women, inaccurately estimate their percentage of body fat. In fact, both men and women primarily estimate their whole body fatness by body weight relative to height.     

Nitrogen accumulation during closed circuit anesthesia depends on the type of surgery

STUDY OBJECTIVE: The aim of this study is to test the hypothesis that the amount of nitrogen that accumulates within the closed breathing system would be greater during open abdominal surgery than during superficial surgery with small wounds. DESIGN: Prospective, comparative study. SETTING: Operating rooms of a university hospital. PATIENTS: Fourteen American Society of Anesthesiologists physical status I and II adult patients scheduled for abdominal surgery (n = 7) or tympanoplasty (n = 7). INTERVENTIONS: After induction of anesthesia and endotracheal intubation, the patients were denitrogenated for 30 minutes using 100% oxygen at a fresh gas flow of 10 L/min. The breathing system was then closed and patients were anesthetized using 60% xenon in oxygen, supplemented with epidural anesthesia in the abdominal surgery group and sevoflurane in the tympanoplasty group. MEASUREMENTS: Nitrogen concentration in the breathing system was determined by gas chromatography immediately before and 2 hours after the breathing system was closed. MAIN RESULTS: The median (range) increase in nitrogen concentration during the 2-hour period of closed circuit anesthesia was greater in the abdominal surgery patients than in the tympanoplasty patients (6.5% [4.0%-10.2%] vs 2.5% [1.4%-8.4%], P = 0.035, Mann-Whitney U test). CONCLUSIONS: The amount of nitrogen accumulation during closed circuit anesthesia is greater during open abdominal surgery than in superficial surgery such as tympanoplasty. We postulate that during open abdominal surgery, nitrogen in the ambient air enters the body across the peritoneum and then diffuses into the alveoli to be exhaled.     

A long-term follow-up study of acute myocarditis an electrocardiographic and echocardiographic study

In an attempt to prove that myocarditis may be a cause of idiopathic cardiomyopathy, 10 cases with acute myocarditis were involved in a long-term follow-up study. There were 9 males and 1 female patient, ranging in age from 22 to 63 years. The etiology of myocarditis was idiopathic in 9 cases and rubella virus in 1 case. Clinical findings in the acute stage consisted of congestive heart failure in 6 cases, Adams-Stokes syndrome in 2 cases and cardiomegaly in 2 cases. The mean follow-up period was 55 months. Follow-up studies included physical examinations, 12-lead ECG, chest X-rays and two-dimensional echocardiograms. Various patterns of residual ECG abnormalities in the chronic stage were found, such as conduction disturbance in 1 case, pseudoinfarction pattern in 4 cases, ST-T changes in 2 cases and premature ventricular contractions in 2 cases. The cardiothoracic ratio of all cases was 60 +/- 4% in the acute stage. Two cases (Case 1 and 2) died 16 and 36 months after the acute onset, respectively. Four cases had residual cardiomegaly even in the last study period. An echocardiographic follow-up study of 7 cases disclosed progressive left ventricular (LV) dilatation and dysfunction in 3 cases, regression of LV dilatation in 2 cases and stable LV function in 2 cases. Two cases out of 3 with progressive LV dilatation and dysfunction expired after the acute illness. It was therefore suggested that acute myocarditis may cause LV dilatation and/or wall hypertrophy and that idiopathic cardiomyopathy may represent the end-stages of previous myocarditis.     

Ultrastructural changes of basal lamina and anchoring fibrils of gingiva in vitro

Biopsies of human gingiva were studied with special reference to the ultrastructural changes of the basal lamina and anchoring fibrils occurring after periods of in vitro cultivation. Characteristic changes were found in the basal lamina and anchoring fibrils. In the early stages in vitro, the basal lamina showed detachment from the epithelial cells, interruption, irregularity in thickness, and reduplication; the anchoring fibrils increased in number. In the later stages in vitro, the basal lamina showed a more severe detachment and fragmentation, proliferation into the connective tissue, and face–to–face coalescence, while the anchoring fibrils became stable in number and free of association with the connective tissue components.     

Angle between the common and internal carotid arteries detected by ultrasound is related to intima-media thickness among those with atherosclerotic disease

Objectives

Although carotid artery structural variations have been detected by ultrasound, their clinical significance is not fully understood. The objective of this study was to determine whether the angle between the common carotid artery (CCA) and the internal carotid artery (ICA), designated angle α, an ultrasound-detectable carotid artery structural variation, is related to carotid artery intima-media thickness (IMT), a surrogate marker for carotid atherosclerosis.

Methods

As a cross-sectional study, we measured angle α in routine carotid artery ultrasounds from 176 subjects (130 men) with atherosclerotic disease/risk factors that attended Kouseiren Hospital in Kagoshima City, Japan between August 2007 and April 2009. We evaluated the correlation between the angle α and CCA- or ICA-IMT.

Results

Angle α was weakly correlated with age but significantly correlated with ICA-IMT. The correlation was stronger in subjects with an ICA-IMT ≥ 0.5 mm than in those with an ICA-IMT < 0.5 mm (Right side r = 0.475 vs. 0.246, Left side r = 0.498 vs. 0.301, respectively). Upon multivariate logistic regression analysis, angle α and serum low-density lipoprotein cholesterol were independent explanatory variables for ICA-IMT.

Conclusion

Angle α is related to ICA-IMT in subjects with atherosclerotic disease or risk factors in this study.

Electronic supplementary material

The online version of this article (doi:10.1007/s12199-015-0453-7) contains supplementary material, which is available to authorized users.     

Use of doubly labeled water to validate a physical activity questionnaire developed for the Japanese population

Background

No study has attempted to use the doubly labeled water (DLW) method to validate a physical activity questionnaire administered to a Japanese population. The development and refinement of such questionnaires require that physical activity components related to physical activity level be examined.

Methods

Among 226 Japanese men and women 20 to 83 years of age, total energy expenditure (TEE) was assessed using the Japan Arteriosclerosis Longitudinal Study Physical Activity Questionnaire (JALSPAQ), and the results were compared with TEE measured by the DLW method as a gold standard. Resting metabolic rate (RMR) was measured using the Douglas Bag method.

Results

The median TEE by DLW and physical activity level (PAL: TEE/RMR) were 11.21 MJ/day and 1.88, respectively, for men, and 8.42 MJ/day and 1.83 for women. JALSPAQ slightly underestimated TEE: the differences in mean and standard error were −1.15 ± 1.92 MJ/day. JALSPAQ and DLW TEE values were moderately correlated (Spearman correlation = 0.742, P < 0.001; intraclass correlation coefficient = 0.648, P < 0.001), and the 95% limit of agreement was −4.99 to 2.69 MJ. Underestimation of TEE by JALSPAQ was greater in active subjects than in less active subjects. Moderate and vigorous physical activity and physical activity during work (ie, occupational tasks and housework) were strongly related to physical activity level. However, the physical activity components that differentiated sedentary from moderately active subjects were not clear.

Conclusions

Physical activity level values on JALSPAQ and DLW were weakly correlated. In addition, estimation of TEE in active subjects should be improved, and the use of a questionnaire to differentiate activity in sedentary and moderately active subjects must be reassessed.Key words: physical activity questionnaire, doubly labeled water, physical activity, energy expenditure