Electropolishing of copper by using different mono, di and poly hydroxyl compounds additives

Electropolishing [EP] technique is one of more efficient methods for cleaning and brightening of metals and alloys. Tarnishing and roughness covering copper surface can be removed by EP treatment imparting a bright and smooth surface at a suitable applied voltage, time and concentration. It was carried out by using an electrolytic cell containing phosphoric acid as the electrolytic solution, copper working electrode and lead counter electrode. Some additives such as soluble starch. ethylene glycol and methanol were added to reduce defects formed on the copper surface during EP operation. The effect of electric potential and time was studied and the surface was also investigated after EP treatment by SEM, EDX and AFM analysis

Detection of reticuloendotheliosis virus as contaminant of fowl pox vaccines

This study was designated to detect reticuloendotheliosis virus [REV] as a contaminant in fowl pox vaccines. A total of 30 fowl pox vaccine samples were examined for the presence of REV using the in vitro and in vivo methods. In the in vitro test, the fowl pox vaccine samples were inoculated into chicken embryo fibroblast [CEF] cultures prepared from SPF embryonated chicken eggs and examined by PCR test for detection of REV. In the in vivo test, each fowl pox vaccine sample was inoculated in five days old SPF chicks and kept under observation up to 12 weeks post inoculation [P1]; serum samples were collected at 15th, 30th, and 45th days P1 for the detection of antibodies against REV by commercial ELISA kit, and tissue samples were collected at 8th and 12th weeks PI for histopathological examination. Results revealed that: only one imported vaccine sample gave positive results by PCR test a product of 291- bp was obtained by the vaccine sample. Serum samples collected from positive vaccine batch were tested for REV antibodies by ELISA test and the sera were positive. Histopathological examination for liver, spleen and bursa of fabricius revealed the presence of tumor cells in the examined organs and these changes confirmed the results obtained by PCR and ELISA tests and indicated that the sample is contaminated with REV. The data clearly indicated that screening of all commercial poultry vaccines to be virus free is an important factor in assuring the biosafety of animal vaccines

Seroprevalence of hepatitis A virus antibodies among a sample of Egyptian children

We determined the seroprevalence of hepatitis A virus antibodies [HAV Ab] among 296 Egyptian children aged 2.5-18 years of different social classes to ascertain whether to give HAV vaccine early in life or to leave children to acquire natural immunity. Overall 61.4% were seropositive for HAV Ab. There was a significant increase in the seroprevalence of HAV Ab with higher age and lower social class; in children aged < 6 years, 72.7% of high and 19.0% of low social class were seronegative for HAV Ab. A national vaccination programme for HAV is not a priority. We recommend vaccination against hepatitis A for high social class children at the preschool period without testing for HAV. Vaccination for middle social class children can be done, but only after testing for HAV

Prevalence of lead toxicity among secondary school students in Sohag city and its impact on cognitive functions

Lead is an extremely toxic metal. Lead intoxication in children has been associated with cognitive impairments. This study was designed to determine the prevalence rate of lead toxicity among secondary school children in Sohag City [Upper Egypt], sources of lead toxicity and the impact of lead toxicity on cognitive function of studied student. The studied students [600] were recruited from three schools, 200 students from Elaskaria school [main stream school] and 400 students from two technical schools [200 from industry and 200 from Elzekhrofia]. A control group was selected from the same sample of studied school, who proved to have normal urinary lead level [<50 micro g/L]. All studied students were subjected to body measurements, clinical evaluation, soft neurological signs, social level, psychometric tests [WAIS, CASI and WMS]. Urine sample were collected for assessment of lead level. The study revealed that the prevalence rate of lead toxicity was 50.5% and the highest rate among studied schools was reported in Elzekhrofia school [62%]. Sources of lead toxicity in this community were old houses [77.9%], presence of repair shops [60.8%], and garbage combustion 60.3%, and smoking [62.1%]. Soft neurological signs were significant abnormal among student with toxic urinary lead level [> 80 micro g/L] in comparison to student with normal lead level [<50 micro g/L] except in one test [standing on one foot]. Student with toxic urinary lead level [> 80 micro g/L] had inverse proportion with social level. There were statistically significant lower scores among students with pre clinical toxicity [>50-80 micro g/L] and toxic level than students with normal urinary lead [<50 micro g/L] in total, verbal and performance Wechsler adult intelligence scale [WAIS], in all Wechsler memory scale [WMS] subitems and in all cognitive abilities screening instrument [CASI] subitems