The biomechanical and morphological changes in the medial collateral ligament of the rabbit after immobilization and remobilization

The effects of immobilization and remobilization on the biomechanical and morphological properties of the femur-medial collateral ligament-tibia complex and each of its components were investigated in the rabbit. Specimens that had been obtained after periods of unilateral immobilization of the knee and remobilization were evaluated for structural properties. In addition, the mechanical properties of the substance of the medial collateral ligament and the histological characteristics of both the substance of the ligament and its sites of insertion were evaluated. After immobilization, there were significant reductions in the ultimate load and energy-absorbing capabilities of the bone-ligament complex, and an increased number of failures occurred by tibial avulsion. The tissue of the medial collateral ligament also became less stiff as a result of immobilization. Histologically, the femoral and tibial insertion sites showed increased osteoclastic activity, resorption of bone, and disruption of the normal attachment of the bone to the ligament. With remobilization, the ultimate load and energy-absorbing capabilities of the bone-ligament complex improved but did not return to normal. Failure by tibial avulsion became less frequent, and the stress-strain characteristics of the medial collateral ligament returned to normal. Histologically, the sites of insertion of the ligament also showed evidence of recovery.     

抗人甲状腺球蛋白单克隆抗体的制备及其对抗原决定簇特异性的研究

用杂交瘤技术建立三株分泌抗甲状腺球蛋白(TG)单克隆抗体的杂交瘤细胞株。所获三种单克隆抗体经兔抗小鼠IgG亚类、IgM及IgA血清鉴定表明,两种为IgG_1,一种为IgA;三种含单克隆抗体小鼠腹水的滴度(ELISA法)均为51200以上;以竞争性固相抗体结合试验测定它们对抗原决定簇的特异性差异,结果发现三种单克隆抗体的抗原结合部位是不同的,但对抗原的结合有一定的相互竞争抑制现象。     

Flavonoids from the leaves ofRhododendron brachycarpum

The flavonoids isolated from the leaves ofRhododendron brachycarpum, were identified as quercetin, avicularin, quercitrin and hyperin.     

A learned odor decreases the number of Fos-immunopositive granule cells in the olfactory bulb of young rats

Olfactory stimulation evokes a column of activity within the olfactory bulb extending from the glomerular layer to the granule cell layer that can be visualized with 2-deoxyglucose autoradiography, optical imaging, Fos protein immunohistochemistry and c-fos mRNA in situ hybridization. The Fos response to odors is typified by the activity of relatively few juxtaglomerular cells, which often occur in foci, and a large number of granule cells extending through much of the bulb. In this study, we characterized the granule cell response to an odor for which young rats had acquired a preference. Fos-like immunoreactive granule cells were quantified by image analysis, and densely stained cells were counted in a region previously shown to be responsive to peppermint odor. We found that odor-trained pups have about half the number of Fos-immunopositive superficial granule cells which respond to a learned odor than do control pups. We then determined whether there was a correlation between the juxtaglomerular cell response and the response of the superficial granule cells deep to those glomerular layer cells. We found a positive correlation between the number of juxtaglomerular cells and the number of granule cells demonstrating Fos immunoreactivity in both control and trained pups, a relationship that changed with early olfactory training.     

Otoconial alterations after embryonic development in hypergravity

The relation between prolonged hypergravity and structural adaptation of otoconia was studied in hamsters (n = 56). Three groups of hamsters (n = 27), were conceived and born in a centrifuge: group 1 (n = 10) 1 month under 2.5 G, group (2n = 9) 5 months under 2.5 G and 4 months under 1 G, group 3 (n = 8) 1 month under 2.5 G and 8 moths under 1 G. Control hamsters (n = 29) were conceived and born under 1 G (1 month old, n = 7; 9 months old, n = 22). Histological study of the otoconial layers (energy dispersive x-ray element analysis and scanning electron microscopy) showed similar calcium content, size, and shape in utricular and saccular otoconia in all groups. Different were the utricular otoconial size classes, large, medium-sized, a and small. The area with small otoconia increased in group 1 (p = 0.002). In group 2, the large otoconial area decreased (p < 0.001) and the medium-sized one increased (p < 0.001). In group 3, the large otoconial area decreased (p = 0.003) and the medium-sized one increased (p = 0.007). For age-related effects we found group 1 with an increased area of large otoconia (p = 0.001) and a decreased medium-sized one compared to groups 2 (p < 0.001) and 3 (p = 0.02). Hypergravity during formation of otoconia does not affect calcium content, size, or shape, but changes relative size of the areas with large, medium-sized, or small otoconia and the development of these areas. This resulted in a structural adaptation to hypergravity.     

VESICO-URETERIC REFLUX AND SURGICALLY TREATED PELVI-URETERIC JUNCTION OBSTRUCTION IN INFANTS UNDER THE AGE OF 12 MONTHS

Background : Pelvi-ureteric junction obstruction has been increasingly diagnosed in infants, mostly as a consequence of antenatal ultrasound examinations. Methods : Of 55 infants below the age of 12 months who underwent dismembered pyeloplasty over a 7-year period, we aimed to determine the patterns and outcome of associated vesico-ureteric reflux that was present in 15 (28%) of the 53 infants in whom follow-up was available. Results : A total of eight infants had resolution of their reflux with conservative management and the median time to resolution was 15 months. Five infants proceeded to ureteroneocystotomy. Conclusions : Given the association of vesico-ureteric reflux and pelvi-ureteric junction obstruction, routine cystography is recommended when the diagnosis of pelvi-ureteric junction obstruction is made.     

Randomised trial comparing the upright and supine positions for the second stage of labour

Objective To assess the maternal and neonatal effects of upright compared with recumbent positions during delivery, in terms of defined outcome variables.
Design A randomised controlled trial.
Setting St Monica's Nursing Home, a midwife based maternity unit in Cape Town, South Africa.
Participants Five hundred and seventeen women of low obstetrical risk assigned to deliver at the nursing home.
Results The trial showed that women who adopted the upright posture for delivery experienced less pain, perineal trauma and fewer episiotomies than those who delivered in the supine position.
Conclusion The data suggest that in women of low obstetrical risk, choice of posture during delivery may be encouraged.     

Isolation of hepatic drug metabolism inhibitors from the seeds ofMyristica fragrans

The hexane extract from Nutmeg, the seed ofMyristica fragrans significantly inhibited hepatic drug-metabolizing enzyme activity. Through systematic fractionation by SiO₂ column and vacuum liquid chromatography monitoring by bioassay, three components, myristicin, (I), licarin-B(II) and dehydrodiisoeugenol(III) were isolated as active principles. Compounds II and III, with a single treatment (200 mg/kg, i.p.) showed not only a significant prolongation of hexobarbital-induced sleeping time but also a significant inhibition of aminopyrine N-demethylase and hexobarbital hydroxylase activities in mice. Compounds I and II provoked a sleep episode at a subhypnotic dose of HB, suggesting that they posses CNS-depressant properties.