[ relationship between serum level of osteoprotegerin and post-laminectomy epidural fibrosis in rabbit]

Epidural fibrosis [EF] is part of natural physiological tissue response to laminctomy and it may be an important cause of failed back surgery syndrome [FBSS]. There is still no effective medical or surgical therapy for EF. Osteoprotegerin [OPG] is a soluble member of the tumor necrosis factor receptor family that might play a role in postoperative EF. The objective of this study was to evaluate the relationship between serum OPG level and EF after laminectomy. Sixty rabbits were employed and divided randomly into two groups. Group A contained 20 rabbits as controls and group B contained 40 rabbits that underwent bilateral laminecyomy at L4 and L5 lumbar levels under an approved surgical protocol. Serum sample was obtained after 8 weeks from all rabbits and then the animals in group B were killed in accordance with the guidelines for euthanasia. The spine segment from L3 to L6 was removed en bloc. The amount of scar tissue at the laminectomy defect was scored on an ordinal score from 0 to 3 with a scoring system similar to that of He et al. According to the amount of scar the rabbits in group B, were divided into two groups: B1 with low fibrosis [grade 0, 1] and B2 with high fibrosis [grade 2, 3]. The serum OPG level of groups A, B1 and B2 were determined using ELISA method. The one way ANOVA was used to assess significant difference among groups. Serum OPG level ranged from 0-4 Pmol/l with a median of 1.5 Pmol/l in group A, 0-6 Pmol/l with a median of 2.42 Pmol/l n group B1 and 0-6 Pmol/l with a median of 2.15 Pmol/l in group B2. There was not any significant difference in OPG levels among these 3 groups. This study showed no relation between OPG level and existence of postlaminectomy EF after 8 weeks

Comparison of serum 25-Hydroxyvitamin D levels in women of childbearing age, oral contraceptive users, postmenopausal and who take hormone replacement therapy

There is a growing awareness that vitamin D sufficiency is required for optimal health, and also the role of vitamin D in calcium absorption and metabolism for bone health is well known. The objective of this study was to investigate the serum vitamin D level in childbearing age and postmenopausal women and comparing with women who use oral contraceptive pills [OCP] and who take hormone replacement therapy [HRT]. Ninety-seven healthy non pregnant-non lactating women with a mean age of 32.67 +/- 5.14 years old [50 OCP users and 47 non- OCP users] and 56 healthy postmenopausal women, with a mean age of 51.42 +/- 3.22 years old [29 were taking HRT and 27 were not taking HRT] were studied using biochemical procedures [measurement of serum 25-hydroxyvitamin D], anthropometric measurements [weight and height] and completing 24-hour recall questionnaire for determining daily dietary calcium intake. No significant differences were found between either OCP and non- OCP users or HRT and non- HRT groups in terms of mean body mass index [BMI], and dietary intakes of calcium. Mean daily calcium intake in all groups was lower than recommended daily allowances. There was no significant difference in serum 25- hydroxyvitamin D levels between OCP- users and non-OCP users, However the mean serum 25- hydroxyvitamin D level in HRT group was significantly higher than that of non- HRT group [P<0.01].The majority of subjects in OCP and non - OCP, and HRT groups had serum vitamin D levels lower than normal limit. Vitamin D deficiency was common in the study subjects, which may have important health consequences. Using low- dose OCP had not resulted in altered Vitamin D metabolism compared to non -OCP users. However, in postmenopausal women, taking HRT had positive effect on serum vitamin D level. It is suggested to emphasize for overcoming vitamin D deficiency in community as one of the health priorities