trace analysis of oxytetracycline and tetracycline residues in pasteurized milk supplied in Tehran: a one-year study [April 2011-March 2012]

Tetracyclines [TCs] are broad-spectrum antibiotics that are widely used in veterinary medicine. The presence of TCs residues in milk is a public health concern all over the world. This study aimed to determine TCs residuals in pasteurized milk marketed by some dairy companies in Tehran from April 2011 to March 2012. 432 pasteurized milk samples were purchased from supermarkets supplying the milk products of 12 major dairy companies in Tehran [3 samples from each company every month], and they were stored at -20 0C until analysis. Oxytetracycline [OTC] and Tetracycline [TC] residues in each sample were extracted by a liquid - liquid phase procedure and quantitated using a high performance liquid chromatographic [HPLC] method. Chromatographic conditions included a mobile phase as oxalic acid buffer- acetonitril [80: 20] with a flow rate of 1mL/min and UVdetection at 355 nm. TCs residuals in most milk samples were lower than 100 ppb, maximum residue level [MRL]; however, in seven samples [1.62%] the total residues of OTC and TC were more than MRL. In the latter milk samples, the median total TCs residue was 625 ppb, ranging between 274 and 1270 ppb. Because of the presence of TC residues above the MRL level in a limited number of milk samples, it is concluded that more studies and supervision of health authorities are needed in this field

[Effects of Zataria multiflora boiss. essential oil and acetic acid on thermostable direct haemolysin production of Vibrio parahaemolyticus]

Consumption of contaminated seafood with Vibrio parahaemolyticus results in gastroenteritis in consumer. Thermostabledirecthaemolysin is one of the major virulence factors of this emerging pathogen which has an important role in its pathogenicity. The objective of this study was to evaluate the effect of Zataria multiflora Boiss. essential oil and acetic acid on the production of TDH toxin of Vibrio parahaemolyticus in subinhibitory concentrations of these preservatives. The toxin production under specific condition including the combination of different concentrations of the essential oil [0, 0.005, 0.015, 0.03 and 0.045%], pH values [5.5, 6.5 and 7.5] modified with acetic acid and 3 incubation temperatures[8, 25 and 35[degree sign]C]in BHI broth medium was studied and the number of the bacteria have been counted and the toxin production has been evaluated after the growth of the organism and subsequent turbidity in the medium using the KAP-Rpla commercial kit. Toxin titerproduced in a broth with pH value of 7.5 and 35[degree sign]C and in the absence of essential oil was 1/256 while it was 1/32 in the same condition and with the presence of 0.015% essential oil. Also the titer of this toxin in 25[degree sign]C and pH of 6.5 equals 1/256 while with adding the 0.015% ofZataria multiflora Boiss. essential oil, It reduced to 1/3. According to the results the essential oil in combination with different pH values and incubation temperatures has a decreasing effect on the toxin production of Vibrio parahaemolyticus. It suggests that further studies with the same conditions as current study in a food model is needed to confirm the positive effect of these natural preservatives

School desk and chair design based on high school female students anthropometry Qazvin, Iran 2007 to 2008

Anthropometry data compiled from body dimensions of female high school students are used to optimize the design of desks and chairs for the classrooms of these students. It is necessary to design suitable desk/chair based on anthropometry data in order to reduce musculoskeletal, visual, circulatory problems, and bad posture during long hours of studying. The goal of this study is to design desks/chairs based on the standard BS 5873 using the body dimensions of 240 female high school students. 240 female students, between the ages of 15 to 17 years old were selected from six different high schools in district 2 of city of Qazvin in Iran. Data for this study were gathered using an interview method and anthropometry measurement devices. Eighteen body dimension parameters of 240 female high school students were obtained. The collected data were analyzed and compared to the standard using SPSS methods. The participant students were divided into 2 groups and customized desk/chair designs were built to fit their body dimensions. There is a significant difference between each customized desk and chair dimension, and standard dimensions used in the industry with an exception of the heights of these designs. We suggest that customized designs based on body dimensions promote correct posture, comfort and health