Characterization of mutations in the VP(1) region of Sabin strain type 1 polioviruses isolated from vaccine-associated paralytic poliomyelitis cases in Iran.

BACKGROUND: The live-attenuated oral polio vaccine used to interrupt poliovirus transmission is genetically unstable. Reversion of some attenuating mutations, which normally occurs during vaccine strain replication in some recipients, and can rarely cause vaccine-associated paralytic poliomyelitis (VAPP). The poliovirus eradication program designed by the World Health Organization (WHO) includes immunization with OPV in addition to careful surveillance of all acute-flaccid paralysis (AFP) cases. OBJECTIVES: In Iran we last isolated imported wild poliovirus in 2000 and the immunization coverage was 100% in 2002. During 2001, there were three AFP cases with residual paralysis from which Sabin-like type 1 polioviruses were isolated in our national polio laboratory. STUDY DESIGN: The complete VP(1) region of the three isolates was sequenced and amino acid substitutions associated with these neurovirulent isolates were recorded. RESULTS: These isolates had either 4, 2 or 1 nucleotide substitution(s) in the VP(1) region, corresponding to amino acid change in the VP(1) of isolate 1 of either (H-[149]->Y), (T-[106]->A) or (I-[90]->L), respectively. CONCLUSIONS: Surveillance of the VAPP cases in countries where endemic transmission has recently ceased increases our understanding of the important neurovirulent mutations in vaccine-strain isolates and assists in planning the next step in the eradication program in these countries.     

Correction to: Frequency-Based Maternal Electrocardiogram Attenuation for Fetal Electrocardiogram Analysis

Annals of Biomedical Engineering -     

Prevention of bone resorption by intake of phytoestrogens in postmenopausal women: a meta-analysis

Phytoestrogens as selective estrogen receptor modulators like compounds may consider as a therapeutic option in osteoporosis. In this regard, the effect of phytoestrogens on bone biomarkers was examined in several trials which their results are controversial. We aimed this meta-analysis to evaluate the net effect of phytoestrogens on bone markers. A thorough search was conducted from 2000 to 2010 in English articles. All randomized clinical trials were reviewed, and finally, 11 eligible randomized clinical trials were selected for meta-analysis. Totally 1,252 postmenopausal women were enrolled in the study by considering the changes of pyridinoline (Pyd), desoxypyridinoline (Dpyd), bone alkaline phosphatase, and osteocalcin concentrations in urine and serum after phytoestrogens consumption. The urine Pyd and Dpyd levels decreased significantly in phytoestrogens consumers. Effect size and effect size for weighted mean difference of urine Pyd levels showed −1.229171 (95% confidence interval (CI) = −1.927639 to −0.530703) and −9.780623 (95% CI = −14.240401 to −5.320845), respectively, a significant results in comparison to control group and significant results for Dpyd −0.520132 (95% CI = −0.871988 to −0.168275) and −0.818582 (95% CI = −1.247758 to −0.389407), respectively. Meta-analysis indicates that phytoestrogens intake can prevent bone resorption, but its benefits on bone formation are not significant. This favorable effect was observed in low doses and in at least 3 weeks of phytoestrogens intake.     

Osseous healing with a composite of allograft and demineralized bone matrix: adverse effects of smoking

We report on our use of a composite graft of lyophilized cancellous allogenic chips and demineralized bone matrix (DBM; Grafton; Osteotech, Eatontown, NJ) to manage traumatic osseous defects and nonunions. Data were prospectively collected from all patients who received this composite bone graft between 1996 and 2000. Only acute fractures with bone loss resulting in a uncontained defect and atrophic non-unions were included in the present study. Demographic data and complications related to composite use, tobacco use, and other comorbidities that could affect healing were evaluated. One hundred seven patients (112 bone graft sites) were followed up for a mean of 32 months (range, 12-60 months). Graft sites included the forearm, femur and tibia. Of the 112 patients, there were 56 smokers (25 non-unions and 31 fractures) and 56 non-smokers (28 fractures and 28 non-unions). Healing occured in 38/56 smokers compared with 49/56 non-smokers. In failed cases, smoking was characteristic in 7/9 non-unions and 11/16 fractures. There were 26 acute uncontained injuries, 29 acute contained defects, and 67 nonunions. Grafting sites were radius/ulna (13 cases), humerus (17), femur (31), and tibia/fibula (51). Significant comorbidities were diabetes mellitus (4 cases), fungal osteomyelitis (1), and pulmonary alveolar proteinosis (1). Eight (73%) of the 11 patients with graft failure had a significant smoking history. This composite graft is an option for managing osseous defects and nonunions traditionally treated with autologous bone grafting but should be used with caution when treating patients who are smokers.     

Effect of folic acid on bone metabolism: a randomized double blind clinical trial in postmenopausal osteoporotic women

Background

In spite of several studies, the impact of homocysteine level and folic acid supplementation on bone metabolism is yet to be recognized. In this registered clinical trial (IRCT2014042217385N1), we aimed to find out the power of 6-month folic acid supplementation on homocysteine level and bone metabolism.

Methods

Forty postmenopausal osteoporotic women (50 to 87 years) were enrolled in the study. All participants were randomized to receive folic acid 1 mg (n = 17) or placebo (n = 14). At baseline, 3 months, and finally 6 months post intervention, the level of homocysteine, vitamin B12, and bone biomarkers were measured.

Results

Both groups were similar at baseline. The homocysteine decreased in both groups but statistically non-significant (P > 0.05). The changes of the serum level of vitamin B12, osteocalcin, and β cross laps were significant between groups after 6 months (P ≤ 0.05).

Conclusion

The trend of changes of bone biomarkers after 6 months folic acid supplementation shows that homocysteine concentration and/or folic acid supplementation have impact on the rate of bone metabolism. However, further investigations by larger sample size and differentiating age and gender are still needed to clarify the exact role of folate, homocysteine and vitamin B12.