المستودع الرقمي لـقسم الكيمياء الحيوية

Background and Aims: Hereditary hemochromatosis (HH) is an autosomal recessive disorder, characterized by increased intestinal absorption of iron. Excessive amount of iron accumulates in the liver, pancreas, and heart, etc., and eventually leading to organ failure due to iron toxicity and death if untreated. The most common causes of HH are the C282Y and H63D mutations in HFE gene. This study aimed to identify the prevalence of H63D and C282Y alleles among the Libyan population in Tripoli region and to compare the results with other published data. Materials and Methods: This study included 300 randomly selected unrelated Libyan male blood donors, aged between 18 and 50 years. In‑house hydrolysis probe real‑time polymerase chain reaction and high‑resolution melting analysis protocols were developed and employed as screening tools for H63D and C282Y genotyping, respectively, and direct DNA sequencing was used to confirm the results. Results: Seven subjects (2.33%) were detected as homozygous H63D mutation and 72 (24%) were detected as heterozygous, and only one subject was detected as a heterozygous C282Y mutant (0.33%) and no homozygous C282Y mutation was detected. Conclusion: In Libyans residing in Tripoli region, the allele frequency of C282Y was very rare and allele frequency of H63D was common arabic 17 English 89
Laila Mohamed Elghawi, Abdulla Bashein(7-2021)

Objective: In Libya, no pertussis booster doses are administered to children after 18 months of age. In light of evidence of waning of vaccine-induced immunity to pertussis, this study aimed to evaluate the waning of immunity in vaccinated school-entry age children, as measured by susceptibility to infection at population level. For this purpose, IgG and IgA levels were measured as markers of recent (infection in the last 6 months) and non-recent infections (infection in the last 12 months). Material and Methods: This was a cross sectional study undertaken in Tripoli, in February 2015. Children of school-entry age (> 5 to ≤ 7 years) were recruited on convenience basis at vaccination centers. Sera were tested for antibodies to pertussis. Results: Samples from791 children (421 males and 370 females, mean age 6.50 were tested). All of the participants had received 4 doses of Whole cell pertussis containing vaccine in the first 2 years of life. The prevalence of recent and non-recent pertussis infection were 4.8% and 2.5%, respectively. The proportion of children with undetectable level of IgG was 76.1%. Conclusion: The findings of this study showed significant circulation of Bordetella pertussis among vaccinated children by school-entry age. The circulation of B. pertussis in this population may be an indirect sign of waned immunity, which is simply corroborated by the absence of detectable antibodies in 76.1% of the children. arabic 14 English 76
Suleiman Abusrewil, Abdulla Bashein(1-2019)

Lipid biochemistry can seem overwhelming, which is why it needs to be explained in a simple and straightforward manner. Ashour Saleh Eljamil, a renowned professor of biochemistry, has written this textbook for undergraduate students in the medical sciences, but its a resource that anyone can use to bolster their knowledge about this important subject. To fully understand biochemistry, you need to know how biomolecules are structured, which is why the first chapter emphasizes the individual chemical structure of various lipid classes. Youll also learn how dietary lipids are digested and absorbed as well as how their metabolism works in separate chapters focusing on fatty acids synthesis, fatty acid oxidation, acylglycerols and sphingolipids, glycolipids, cholesterol, plasma lipoproteins, steroid hormones, and fat-soluble vitamins. While scientists have studied lipid biochemistry for three centuries, its only in the past few decades that weve begun to understand why its so important. Gain a clearer understanding of the world with insights about bile acids, sterols, carotenoids, sex hormones, vitamin K and much, much more when you dive into the world of Lipid Biochemistry. arabic 5 English 35
Ashour Eljamil(3-2015)

Every organism has deoxyribonucleic acid (DNA) within their cells. DNA is a complex molecule that contains all of the information needed to build and maintain living organisms. Extraction of deoxyribonucleic acid (DNA) is one of the most basic and critical steps affecting molecular-based techniques in the study of DNA that allow vast advances in genetic, molecular biology, biotechnology, forensic, and bioinformatics laboratories. Therefore, researchers have been used different modified and optimized protocols for efficient genomic DNA extraction from biological samples. Due to the high amount of genetic material in whole blood samples so it's one of the main sources used to obtain DNA and there are many different protocols available in this issue. In the present study, we optimized, evaluated by comparison to phenol-chloroform (traditional method) and silica column (QIAamp DNA Blood Mini Kit) DNA extraction procedures. The extracted DNA by these protocols was analyzed according to their time consuming, quality, quantity, cost and toxicity. Extracted DNA with current protocol was qualified using gel electrophoresis, Nanodrop spectrophotometric analysis. Our results showed that there are not significantly differences between these methods about DNA Purity (A260/A280) and DNA yield (ng DNA/μl). In addition, phenol/chloroform (traditional method) was the most toxic method; it takes more time but cheaper than other method; it yielded reasonably good quantities of good quality DNA and would be suitable for large-scale genotyping of blood samples. The silica column method (QIAamp DNA Blood Mini Kit) was the most expensive among the other method but the least extraction time was required and it was the safest method. arabic 11 English 69
Ghada Salem, Ahmed Zaid(1-2018)

Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common genetic kidney disorders with the incidence of 1 in 1,000 births. ADPKD is genetically heterogeneous with two genes identified: PKD1 (16p13.3, 46 exons) and PKD2 (4q21, 15 exons). Eighty five percent of the patients with ADPKD have at least one mutation in the PKD1 gene and fifteen percent of the patients have one mutation in PKD2 gene. Direct sequencing of one patient and his sequence of PKD1 gene demonstrated a missense mutation GCC----CCC substitution in exon 13 with cause change amino acid of Alanine to Proline at codon 1029. Three brothers have deletion mutation in exon 15, one patient missense mutation GGC---GCC in exon 19 which cause change amino acid of Glycine to Alanine at codon 2530. Molecular diagnostics of ADPKD relies on mutation screening of PKD1 and PKD2, which is complicated by extensive allelic heterogeneity and the presence of six highly homologous sequences of PKD1. PCR strategy was used to screen sequence variants with heteroduplex analysis and several affected individuals were discovered to have clusters of base pair substitutions in exons 13 and 19 with del 20 pb (3601-3620) in exon15. arabic 14 English 81
Refaat Tabagh, Ahmed Zaid(1-2018)

Abstract: Familial hypercholesterolemia (FH) is an autosomal dominant genetic disorder of lipid metabolism, associated with elevated levels of low-density lipoprotein-cholesterol (LDLC), which can lead to premature cardiovascular disease and early death. Early diagnosis and initiation of treatment is important to prevent morbidity and mortality. Autosomal dominant hypercholesterolemia (ADH) is largely due to mutations in the low-density lipoprotein receptor gene (LDLR), the apolipoprotein B-100 gene (APOB), or the proprotein convertase subtilisin/kexin type 9 (PCSK9). In this study, genomic DNA of unrelated Libyan individuals with clinically diagnosed (FH) was analyzed by direct sequencing after dependent specific PCR primers amplification and DNA purification. That led to the identification of PCSK9 gene mutations for the first time in Libyan population which was compare to other populations. All 12 exons of PCSK9 gene and boundaries genotyped polymorphisms were sequenced, including leucine repeats coded in exon 1, by fluorescently tagged markers. We identified an allele for the rs67610340 polymorphism: an in-frame deletion, c.61_63delCTG (L8). We also identified another allele rs67610340 polymorphism: an in frame insertion c.61_63InsCTG (L10). The insertion and deletion alleles were both in exon 1 and could be associated with a risk and severity of coronary artery disease (CAD), suggesting a direct effect of PCSK9 on atherogenesis. arabic 11 English 90
Ghada Salem, Ahmed Zaid(1-2017)

Introduction: Chronic granulomatous disease (CGD) is a rare inherited primary immune deficiency disease with prevalence of 1 in 250,000 worldwide. It is caused by mutations in the genes that encode the NADPH oxidase enzyme components responsible for the production of super oxide and other free radicals. These mutations lead to the absence or decrease of the microbicidal activity of the phagocytic cells. arabic 10 English 72
Muna Hamed Othman Elramli, Ahmed Zaid(1-2015)

The GC-box is an important transcriptional regulatory element present in the promoters of many mammalian genes, and is found in most, if not all, oxidative phosphorylation (OXPHOS) promoters. In the present study we examine the effects of three Sp1 family members (Sp2, Sp3, and Sp4) on the adenine nucleotide translocase 2, cytochrome c1, F1-ATPase β-subunit, and the mitochondria transcription factor (mtTFA) promoters in Drosophila SL2 cell line. Sp3, like Sp1, strongly activates transcription all four promoters. SP4 stimulates, moderately, but Sp2 had no effect. In addition, Sp3 can, like Sp1, inhibit transcription from the proximal promoter of the ANT2 gene through binding to the Cbox GC element. By contrast, Sp4 and Sp2 do not repress promoter activity. Furthermore, since Sp4 and Sp2 bind to the Cbox repression element on the ANT2 promoter, but do not repress transcription, inhibition of transcription … arabic 21 English 97
Ahmed Zaid(1-2012)