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Al-Qahtani A.,King Faisal Specialist Hospital And Research Center | Al-Hazzani T.,University of Princess Nora Bent Abdul Rahman | Al-hussain T.,King Faisal Specialist Hospital And Research Center | Al-Ghamdi A.,King Faisal Specialist Hospital And Research Center | And 5 more authors.
Cancer Genetics and Cytogenetics | Year: 2010

Amplification of the two oncogenes ERBB2 and MYC and deletion of the tumor suppressor gene TP53 are frequently encountered in cancerous tissues. The purpose of this study was to use the fluorescence in situ hybridization (FISH) technique for the assessment of ERBB2 and MYC amplification and TP53 deletion, and to relate these molecular markers to clinical and pathologic factors in Saudi patients with hepatocellular carcinoma. The study was conducted on 40 paraffin-embedded tissue samples originally taken from either hepatitis C virus (HCV)- or HBV-infected patients using the FISH technique. The level of ERBB2, MYC, and TP53 in the malignant group was significantly increased as compared to the control group. Of the 40 patients, 3 (7.5%) had amplification of ERBB2 gene, 4 (10%) different patients had amplification of MYC, and 26 patients (65%) had evidence of deletion of at least one allele on chromosome 17 for the TP53 gene in a high proportion of cells. There was a significant correlation between amplification of MYC oncogene and the number of tumor masses. Moreover, significant correlation was observed between poorly differentiated tumors when compared with moderate or well-differentiated tumors when MYC was analyzed. On the other hand, MYC failed to reveal any significant association between oncogene amplification and other clinicopathologic variables examined. Univariate analysis revealed a strong association between deletion of TP53 and multiple tumor mass (P< 0.001). No statistical correlation could be detected between deletion of TP53 and tumor size, grade, stage, and tumor differentiation. No significant difference could be detected in the mean survival time of patients positive for the alteration of the genes compared to the patients who showed no alterations for the same genes. However, when the stage of the tumor was analyzed, there was a significant difference in the mean survival time between patients who showed gene alterations compared to patients with no changes in the studied genes. When overall survival was analyzed, only patients with MYC amplification had a lower median survival (20.75 months) than patients without MYC amplification (35.82, P=0.009). Genetic alterations of ERBB2 and TP53 genes had no effect on survival 2 (see Results). The combination of ERBB2, MYC, and TP53 could be useful markers to stratify patients into different risk groups. © 2010 Elsevier Inc. Source

Alwakeel S.S.,University of Princess Nora Bent Abdul Rahman
Saudi Journal of Biological Sciences | Year: 2013

Fungi causes most plant disease. When fruits are stored at suboptimal conditions, fungi grows, and some produce mycotoxin which can be dangerous for human consumption. Studies have shown that the Penicillium and Monilinia species commonly cause spoilage of fruits, especially apples. Several other genera and species were reported to grow to spoil fruits. This study was conducted to isolate and identify fruit spoilage by fungi on apples collected in Riyadh, Saudi Arabia and conduct a molecular identification of the fungal isolates. Thus, we collected 30 samples of red delicious and Granny Smith apples with obvious spoilage from different supermarkets between February and March of 2012 in Riyadh, Saudi Arabia. Each apple was placed in a sterile plastic bag in room temperature (25-30. °C) for six days or until fungal growth was evident all over the sample. Growth of fungal colonies on PDA was counted and sent for molecular confirmation by PCR. Six fruit spoilage fungi were isolated, including Penicillium chrysogenum, Penicillium adametzii, Penicillium chrysogenum, Penicillium steckii, Penicillium chrysogenum, and Aspergillus oryzae. P. chrysogenum was the most frequent isolate which was seen in 14 of a total of 34 isolates (41.2%), followed by P. adametzii and A. oryzae with seven isolates each (20.6%) and the least was P. steckii with six isolates (17.6%). Penicillium species comprised 27 of the total 34 (79.4%) isolates. Sequence analysis of the ITS regions of the nuclear encoded rDNA showed significant alignments for P. chrysogenum, P. adametzii and A. oryzae. Most of these fungal isolates are useful and are rarely pathogenic; however they can still produce severe illness in immune-compromised individuals, and sometimes otherwise healthy people may also become infected. It is therefore necessary to evaluate the possible production of mycotoxins by these fungi to determine a potential danger and to establish its epidemiology in order to develop adequate methods of control. © 2013 . Source

Alwakeel S.S.,University of Princess Nora Bent Abdul Rahman
Advances in Environmental Biology | Year: 2013

Several studies have shown that some microbes and fungi contaminate sea water. We conducted this study to investigate and identify bacterial and fungal species in Red Sea near Jeddah, Saudi Arabia. Water and sand samples were collected in March 2012 via sterile screw cap bottles and isolated using nutrient agar, Sabouraud agar, Glucose-Czapek and Petroleum oil-Czapek agars. Baterial sensitivity testing was done for bacterial isolates. There were a total of 18 fungal genera isolated. On Glucose-Czapek agar, including the genus Aspergillus and Penicillium. On Petroleum oil - Czapek agar, there were a total of six fungal genera that were isolated including Aspergillus and Penicillium. Bacterial isolates included Pseudomonas fuorescens, Pseudomonas putida, Pseudomonas stutzeri, Pasteurella multocida and Serratia species. Antibiotic susceptibility tests on bacterial species showed sensitivity to most antibiotics. There is a need to inform the public of the potential dangers of infection from contaminated sea water and sand. It is best to maintain good hygienic practices by immediately bathing in potable water after swimming or diving in the sea, which is a possible source of transmission route for fungi and bacteria. Source

Alwakee S.S.,University of Princess Nora Bent Abdul Rahman | Nasser L.A.,University of Princess Nora Bent Abdul Rahman
American Journal of Food Technology | Year: 2011

The occurrence of harmful aflatoxins from agricultural products varies with geographic location, farming practices and processing. To date, no data was reported from Saudi Arabia on mycotoxin content of nuts and edible seeds. Forty samples of edible nuts and dried seeds were randomly collected from different locations in Al-Riyadh, Saudi Arabia. Fungi were detected by seed-plate and dilutions plate method and were cultured on glucose-Czapek's agar, sucrose-Czapek's agar and starch yeast agar. Purified fungal isolates were identified morphologically. Mycotoxins were extractedusing chloroform and detected by thin layer chromatography. Bacterial analysis was done using total plate count method. There was a predominance of A. niger and A. flavus in all medium types. Aflatoxin B1 (8.5 μg mL-1) was detected in peanuts containing A flavus. Aflatoxin B1 (1.7 μg mL-1) and B2 (1.7 μg mL-1) was detected in sunflower seeds containing A terreus. T2 toxin (2.8 mg mL-1) was detected in pumpkinseeds containing Stachybotrys chartarum and DAS (2.4 μg mL-1) was detected in a salted peanut sample containing Trichthecium roseum. Four nut samples showed contamination with bacteria. Turkish pine seeds and American walnut had total plate counts of 12×10. Pakistani pine seeds and Iranian salted pistachio had TPC of 3×10. Listeria monocytogenes was isolated from American walnut samples. Government authorities for food safety consumption should continue to monitor and set appropriate guidelines and information initiatives for public knowledge on the safety of these agricultural products whole year round. © 2011 Academic Journals Inc. Source

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