S.t Mirmohammadi, E Hakimi, O Ab Kadir, M Mohamadian , K Kamel,
Volume 18, Issue 63 (Mar 2008)
Abstract
Background and Purpose: MDI (Methylene Diphenyl Diisocyanate) is a high tonnage product, which comprises about 90% of the total diisocyanate in the market. Polyurethanes are produced by reacting diisocyanate with polyols and other chemicals. They are known as respiratory tract and skin sensitizers and are the most common cause of occupational asthma in the world (NIOSH 1994). On this subject, evaluation of MDI concentration in the polyurethane factories by HPLC, and is worthy to determine its pollution level.
Materials and Methods: All sampling methods have some limitation, therefore, this survey the method of NIOSH 5522 has been used as a standard sampling and analyzing method t then, we utilize SPSS V.13 software, for our data to be analyzed for statistical discussion.
Results: Results showed that all of the polyurethane industries under this study have high concentration, rate of more than 80 µg/m³. There was a strong correlation between indoor temperature and high MDI concentration, thus, it implies that various temperatures may be increased, in addition to working time ensuring it has a good correlation with MDI concentration. It also implies that when ever they have more working time comparatively, in turn, they have high exposure rate of MDI pollutant in the workplace.
Conclusion: To obtain a better way for determination of MDI concentration in the workplace is using biological monitoring as a standard method to survey the exposure to diisocyanate, by using metabolite determination, it will be easier to collect and analyze more samples as the sampling is not as time-consuming as air monitoring.
Hadi Naddaf, Fereydoon S Aberi Afshar, Babak Mohamadian, Abdolvahed Moarebi, Amir Reza Imani, Soroush Sabiza,
Volume 25, Issue 123 (4-2015)
Abstract
Background and purpose: Auto-transplantation is the best bone graft substitute, but there are some limitations. Therefore, other methods using synthetic or natural materials are recommended. Propolis is a resinous natural product derived from plant exudates collected by honeybees. It has been extensively used in folk medicine because of its biological and pharmacological activities. The present study was carried out to evaluate the osteogenic properties of propolis on healing of diaphyseal defects in rabbit ulna.
Materials and methods: In this study ten healthy adult male white New Zealand rabbits were used. The animals were randomly divided into control and treatment groups (n=5 per group). Three millimeters defects were created in right diaphysis of ulna in all animals and intramedullary pins were used for bone fixation. In treatment group the defects were filled with propolis but in control group the defects were left unfilled.
Results: Radiological study showed that propolis as a scaffold could somewhat guide the bone growth. Histological section showed moderately differentiated lamellar bone in the cortical part with presence of haversian canal at peripheral cortex, whereas fibrocollagenous tissue and good amount of bone marrow tissue, fat cells and bone vessels were observed in control group. The results showed no significant difference in bone healing between the two groups.
Conclusion: Propolis have biological materials, minerals and amino and organic acid properties, therefore, further studies are required to clarify the efficacy of propolis on bone healing.
