Safaa Y. Qusti

Mineral content and microbiological examination of some white cheese in Jeddah, Saudi Arabia during summer 2008

Different local and exported white cheese samples were collected from different markets in Jeddah during September 2008. Trace and heavy metals including Pb, Zn, Mn, Cu, Fe and Cd were analyzed using atomic absorption spectrometry. The concentration of the tested metals was in the range, Fe(++)>Zn(+++)>Mn(++)>Pb(++)>Cu(++)>Cd(++). The mean concentration of 7.63, 7.19, 0.5, 0.47, 0.16 and 0.14 μg/g was recorded for Fe, Zn, Mn, Pb, Cu and Cd, respectively. The concentration of iron ranged from 3.5 to 11.9 μg/g, zinc from 3.4 to 10.5, manganese from 0.12 to 1.0, lead from 0.14 to 1.14, and copper from 0.09 to 0.22. Yeasts and fungi were counted on Sabouraud and Potato Dextrose media and incubation was carried out at 25°C for 7 and 5 days, respectively. Yeast count and fungi count of cheese were ranged from 0.1 to 0.44CFU/g and from 0.123 to 1.11 CFU/g, respectively. Three out of 20 samples of cheese were contaminated with toxigenic fungi with 5% contamination level. Aflatoxin G1 was recorded in three samples using immunoadsorbent column chromatography with a range from 7 to 13 ppm.

Thyroid function in newly diagnosed HIV-infected patients.

Background: A variety of HIV-related endocrine dysfunctions including adrenal, gonadal and thyroid disorders have been reported. We aimed to compare between the markers of thyroid function in newly diagnosed HIV-infected patients and healthy volunteers as a control group. The prevalence of the thyroid abnormalities in HIV-infected patients was assessed and the levels of thyroid autoantibodies were also determined. Methods: A total of 100 newly diagnosed HIV-infected patients having a CD4 cell count of 180–350 cells/mm3 were enrolled in the study. Same number of healthy volunteers were also included for comparison. Measurements of thyroid function tests including thyroid-stimulating hormone (TSH), free thyroxin and free triiodothyronine levels beside thyroid autoantibodies, including antithyroglobulin (ATBG) and antithyroid peroxidase (ATPO), were carried out for all patients and volunteers. Results: In total, 70% of HIV-infected patients had normal thyroid function tests when compared with control individuals, while 30% of HIV-infected patients had abnormal thyroid function. Of the 30 cases, 11 cases had abnormal TSH values, with increased TSH predominant (7% of HIV cases) than decreased TSH (4% of patients) values. Incidence of thyroid abnormalities ranging from hypothyroidism (subclinical and overt: 6% and 1%, respectively) to hyperthyroidism (2%) and nonthyroidal illness (9%) were estimated in HIV-infected patients. The values of thyroid autoantibodies were almost normal in HIV-infected patients, except the three cases presented with elevated ATBG, indicating that thyroid abnormalities were not due to elevated ATBG and ATPO. Conclusions: Thyroid hormones are of great importance and due to high prevalence of thyroid function abnormality, it is recommended that thyroid function tests should be monitored in all HIV-infected patients before starting the treatment.

Cytotoxicity and Antimicrobial Activity of Nerium oleander Extracts

Abstract El Sawi, N.M., Geweely, N.S., Qusti, S., Mohamed, M. and Kamel, A. 2010. Cytotoxicity and antimicrobial activity of Nerium oleander extracts. J. Appl. Anim. Res., 37: 25–31. The antimicrobial properties of the crude and pure extracts of Nerium oleander were investigated against three Gramve bacteria (Escherichia coli, Pseudomonas aeruginosa and Salmonella enteritidis), three Gram +ve bacteria (Bacillus subtilis, Listeria monocytogenes and Staphylococcus aureus) and six fungal species (Aspergillus flavus, A. fumigatus, A. niger, Fusarium moniliforme, Penicillium expansum and Rhizopus oryzae). The crude extract of N. oleander was more effective than purified compound. The maximum antimicrobial activities (15 and 20 mm inhibition zone) was exhibited by the crude extract of N. oleander against the most sensitive isolates (B. subtilis and A. flavus), respectively, while all pure constituents showed trace to no antimicrobial activity against the tested microorganisms. The lowest value (25 μg/ml) of minimum inhibitory concentration of the active crude extract of N. oleander was revealed with A. flavus.

Effect of Nigella sativa L. Oil on Roridin E Toxin Administration on Liver of Male Mice

Abstract Qusti, S.Y. and El-Sawi, N.M. 2007. Effect of Nigella sativa L. oil on roridin E toxin administration on liver of male mice. J. Appl. Anim. Res., 31: 161–164 To study the effect of Nigella sativa L Oil (N.S.) on mice given roridin E toxin, 30 albino mice were divided in 3 equal groups. Control group mice were given only the carrier of roridin E. Second group mice were given roridin E (2 mg/kg bw). Third group mice were given toxin as in group 2 but were given 800mg/kg bw of NS oil additionally. Liver tissue and blood serum analysis indicated that lipid peroxidation parameters were increased by toxin but NS oil brought these to normal level. Thus NS oil as antidote to rordin E toxicity is demonstrated.

Cysteine-mediated excitotoxic neuronal death is an apoptosis - Necrosis continuum

Abstract Qusti, S.Y., Parsons, R.B., Waring, R.H. anRamsden, D.B. 2007. Cysteine-mediated excitotoxic neuronal death is an apoptosis—necrosis continuum. J. Appl. Anim. Res., 32: 7–12. To explore the mechanism whereby cysteine induces cell death this study was undertaken using a human medulloblastoma cell-line as the model system. Low levels of cysteine induced several well described phenomena associated with apoptosis, phospatidyl serine exposure, mitochondrial membrane disruption, cleavage of DNA into 50 Kb fragments and induction of caspase 3, whereas higher concentrations tended to cause necrosis. We have speculated on the role of cysteine in excitotoxicity, which occurs clinically following cerebral ischemia.