Purpose: The etiology of Legg-Calve-Perthes disease (LCPD) remains unknown until today. A few studies have suggested passive smoke inhalation may be a risk factor, although the association is not confirmed and a causal relationship has not been established. Most mothers who smoke during pregnancy may continue smoking after giving a birth, it would be difficult to determine to what extent passive smoke inhalation adds to the risk of LCPD in these children. The causes of Legg-Calve-Perthes disease are largely unknown, but this pediatric disease seems to result from interruption of the blood supply to the proximal femur and is considered a vascular disease. Because maternal smoking during pregnancy influences fetal development and is associated with cardiovascular diseases in offspring, we hypothesized that this exposure and passive Tabaco smoke exposure are risk factors for Legg-Calve-Perthes disease and also investigated other markers of impaired fetal development and early-life exposures. Methods: We prospectively recruited total 96 patients, among those 32 patients with LCPD as a case group and 64 patients attending the hospital for other orthopedic complaints as control group. Conditional logistic regression was used to assess the association between the exposures and risk of LCPD. Results: The main risk factors for LCPD were family background, indoor use of a wood stove, having a family member who smoked indoors (passive smoke) and smoke during pregnancy. Children from the middle socioeconomic group appeared to be at a greater risk of developing LCPD. Conclusions This study provides further evidence that environmental tobacco smoke is associated with an increased risk of LCPD. Family background and exposure to wood smoke also appears to be risk factors. Maternal smoking during pregnancy and other factors indicated by impaired fetal development may be associated with an increased risk of Legg-Calvé-Perthes disease. However, it remains unclear why there are profound differences in the incidence of the disease between regions when the prevalence of smoking is comparable and why bilateral involvement is infrequent, and it needs further study.

Introduction: Quality of pharmaceutical products is very important because drugs must be marketed as safe and therapeutically active formulations whose performance is consistent and predictable. The evaluation of the physical characteristics of the pharmaceutical products can ensure their quality as well as bioavailability and impart optimum therapeutic activity. Metronidazole was chosen for this comparative study because this drug is widely used worldwide in the treatment of amoebiasis and other microbial diseases. Method: The quality control parameters of five different brands of metronidazole 500 mg tablets were determined weight variation, friability, hardness, and disintegration, dissolution and assay tests. All the tablets were evaluated for conformity with British Pharmacopoeia (BP) and Mongolian Pharmacopoeia-National Formulary (MP-NF) standards. Results: Among five brands of tablets Brand М3 had lower mean weight variation of 0.8% and Brand М1 had highest mean weight variation of 3.42%. For friability test Brand М2 had the lowest mean friability (0.57) and Brand М1 had highest mean friability (1.51). The disintegration time for five brands of ciprofloxacin tablet obtained were in the subsequent order: Brand М1 (2.82 min) < Brand М3 (8.8 min) < Brand М4 (12.32 min) < Brand М5 (13.82 min) < Brand М1 (39.22 min). Conclusion The present study revealed that all of the leading brands (M1, M2, M3, M4, M5) of this tablet met the quality control parameters as per pharmacopoeial specifications.