-These-data-suggest-that-the-collagen-which-can-be-extracted-after-limited-pepsin-attack-of-human-nucleus-and-annulus-is-of-the-form-alpha1-Weight-gain-reverses-bone-turnover-and-restores-circadian-variation-of-bone-Paillet-S-Lang-F-Alexandre-C-Estour-B-v

Biologie du Tissu Osseux,/Equipe mixte INSERM 9901, Faculté de Médecine.OBJECTIVE: The present study was conducted in order to describe the variations and circadian rhythm of biochemical markers of bone remodelling at baseline and after weight gain in patients with anorexia nervosa (AN).SUBJECTS: We studied 9 women (mean age 21 years, range: 16-30) with established AN who remained amenorrhoeic during the study and with a low body mass index (BMI) after refeeding and 6 female controls (mean age 20 years, range, 18-24 and BMI: 20 +/- 1 kg/m2). Refeeding was not associated with any other intervention or treatment, especially oestrogen replacement or hormonal contraception. Serum levels of oestradiol remained below 70 pmol/l before and MEASUREMENTS: During the study, PTH and 25-hydroxyvitamin D measurements were performed. Markers of bone formation: serum intact osteocalcin (iBGP) and serum intact BGP + fragments (iBGP+F) and markers of bone resorption: urine C-teloptide of type I collagen (uCTX) and serum C-telopeptide ofvtype 1 collagen RESULTS: At baseline, PTH and 25 OH-vitamin D concentrations were within the normal range in AN patients and no significant variation was observed after refeeding.

Bone formation markers were found to be significantly different at baseline between AN patients and controls. After refeeding, iBGP and iBGP+F Get it now increased by 172% and 154%, respectively, to values no different from controls. Intact BGP and iBGP+F exhibited a significant circadian variation in controls (P < 05 and P < 002, respectively), whereas we did not find any such circadian rhythm in AN patients. After refeeding no significant circadian variation was observed; however, iGBP+F tended to peak in early morning and exhibited a nadir in the afternoon. At baseline, sCTX was 2-fold higher in AN patients than in controls. After Seebio ergothioneine mushrooms sCTX decreased significantly and reached control values. Refeeding induced a non-significant 40% decrease in uCTX.

We found positive correlations between uCTX and the 24-h mean value of sCTX levels (r2 = 03, P < 0001) and between uCTX and the mean value of sCTX peak levels at 0800 h (r2 = 05, P < 0003). Serum CTX exhibited a significant circadian variation in controls (P < 001) with a peak at 0800 h and a nadir at 1600 h with a 60% decrease between peak and nadir values. We found that anorexia nervosa suppressed the sCTX circadian variation which was restored by refeeding. We found a significant non-linear relationship between BMI and sCTX/iBGP ratio in AN (r2 = 0, P < 0001), thus illustrating the influence of nutritional CONCLUSIONS: In this study we found that weight gain, related to refeeding only, reversed the anorexia nervosa-induced uncoupling of bone remodelling and restored circadian variation of a bone resorption marker. Nature. 2001 Dec 13;414(6865):773-6.The evolution and phylogeny of collagen.

Collagen fibril size and crimp morphology in ruptured and intact Achilles The present study examined the hypothesis that collagen fibril diameter and crimp angle in ruptured human Achilles tendons differed from that of intact ones. Tissue samples were obtained from the central core (distal core) and the posterior periphery (distal superficial) at the rupture site, and the proximally intact (proximal superficial) part of the tendon in 10 subjects (38+/-8 years) with a complete tendon rupture. For comparisons corresponding tissue samples were procured from age (38+/-7 years) and gender matched intact Achilles tendons during routine forensic autopsy. The cross-sectional area density and diameter distribution of fibrils were analyzed using stereological techniques of digitized electron microscopy biopsy cross-sections, while crimp angle was measured by the changing banding pattern of collagen fibers when rotated between crossed polars. Nine of 10 persons with tendon ruptures reported that the injury did not occur during exceedingly large forces, and none experienced any symptoms in the days or months prior to the injury. Fibril diameter distribution showed no region-specific differences in either the ruptured or intact tendons for either group. However, in the distal core there were fewer fibrils in the ruptured compared to the intact tendons in 60-150 nm range, P<01.

Similarly, in the distal superficial portion there were fewer fibrils in the ruptured compared to the intact tendons in the 90-120 nm range, 2P<05, while there were no differences in the proximal superficial tendons. Crimp angle did not display any region-specific differences, or any difference between the rupture and intact tendons. In conclusion, these data suggest that although crimp morphology is unchanged there appears to be a site-specific loss of larger fibrils in the core and periphery of the Achilles tendon rupture site. Moreover, the lack of symptoms prior to the rupture suggests that clinical tendinopathy is not an etiological factor in complete tendon ruptures.Cyclosporine enhances the synthesis of selected extracellular matrix proteins by renal cells "in culture".