https://www.um.edu.mt/library/oar/handle/123456789/8426 Wed, 08 Apr 2026 04:01:58 GMT 2026-04-08T04:01:58Z https://www.um.edu.mt/library/oar/handle/123456789/8931 Title: Antimicrobial efficacy of a novel assisted ultrasound technology Abstract: Two different essential oils (oregano and thyme essential oils) were tested with the continuous and pulse 2s on/ 8s off mode . The concentrations of oregano essential oil tested were : 0 .0 10%, 0. 01 4%, 0. 0 18%, 0. 02 2% an d 0 .0 25% v /v , while with thyme essential oil the same concen t r a t io ns p lu s 0 .0 4% v/ v were tested. Application of both oregano and thyme essential oils at the mentioned concentrations further reduced the levels of bacteria from the surface. Significant differences were found at concentrations of 0 .0 18%, 0 .0 2 2% and 0 0 25% v/v of oregano essential oil with both continuous and pulsed modes when compared to the samples treated with US alone , while for thyme essential oil significant reductions were observed with 0.01 8% v/ v and higher concentrations for continuous mode, and 0 . 01 4% v/ v an d higher concentrations for pulsed mode. Only the highest concentration of thyme essential oil (0.04% v/ v) using both continuous and pulsed mode reduced the levels of Salmonella in water below the limit of detection. The effectiveness of the assisted ultrasound process was dependent on the processing times rather than the configuration of the ultrasound used (continuous versus pulsed mode) . When the antimicrobial efficacy of oregano and thyme essential oil were compared, it was evident that oregano essential oil was more effective at detaching the bacteria from the surface of the lettuce, while thyme essential oil was more effective at inactivating the bacteria from the wash water . The use of both oregano and thyme essential oils proved to show synergistic effects in enhancing the removal and inactivation of the bacteria from the surface of the lettuce. The energy applied to the ultrasound system was also optimized , to obtain maximum reduction in bacterial levels with minimum energy being utilised. Description: B.SC.(HONS)BIOMED.SCI. Thu, 01 Jan 2015 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/8931 2015-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/8864 Title: Validation of a PCR technique for kidd blood group genotyping Abstract: The Kidd blood group antigens, Jka and Jkb, are two of the main surface markers which are found on the red blood cells’ membrane. The determination of whether a donor or a recipient has the Jka and/or the Jkb antigens is crucially important in order to have a successful transfusion without the development of adverse incompatibility-related reactions. In Malta, routine serological-based tests are applied with the purpose of differentiating between homozygous and heterozygous states for the Jk antigens respectively. Although these tests are highly specific and sensitive, there are particular clinical scenarios where haemagglutination assays are not suitable for determining the individual’s Kidd blood group status. Additionally, the alternative genotyping procedure has never been applied in Malta within the context of molecular transfusion. Thus, this study was performed to determine whether Polymerase Chain Reaction - Restriction Fragment Length Polymorphism (PCR-RFLP) is suitable for distinguishing amongst the three different Kidd phenotypes. After extracting 50 DNA from blood samples obtained from serologically-tested healthy donors who expressed at least one of the Kidd antigens, PCR-RFLP analyses were carried out and the results of the latter were compared with the ones previously obtained with haemagglutination. Since the results of both tests were a complete match with one another, the PCR-RFLP method was confirmed as a suitable laboratory technique that can be used to determine the Kidd blood group of donors and recipients. Description: B.SC.(HONS)BIOMED.SCI. Thu, 01 Jan 2015 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/8864 2015-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/8862 Title: Interleukin 6, white blood cell count and risk of myocardial infarction Abstract: Interleukin 6 (IL-6) is pro-inflammatory cytokine which is reported to have a positive association with total and differential white blood cell (WBC) levels. Elevated white blood cell levels have been implicated as an independent risk factor of cardiovascular disease and myocardial infarction (MI). Single nucleotide polymorphisms (SNP) located within the promoter region of the IL6 gene have been associated with elevated serum IL-6 levels. The aim of this study is to determine whether the IL-6 -597 G→A promoter polymorphism influences white blood cell count and therefore the risk of MI. The results of this study indicate that there is no increased risk of myocardial infarction (MI) associated with the IL-6 -597 G→A polymorphism when including all cases and controls [1.0 (95% CI 0.4 – 2.2) in homozygous mutants and 1.0 (95% CI 0.7 – 1.3) in heterozygotes], after adjusting for age and gender. The polymorphism shows no interaction with smoking, a wellestablished risk factor of MI. No significant differences are observed in the blood cell levels of men and women carrying the IL-6 -597A allele when compared to their wildtype counterparts. These results remain generally unaltered in males after excluding smokers and quitters from blood cell analysis and observing levels in non-smokers. Female smokers who lack the IL-6 -597A allele have significantly higher WBC levels than carriers while female non-smokers carrying the allele have higher WBC levels than homozygous wildtypes, suggesting a possible antagonistic interaction between the genotype and smoking. The IL-6 -597A allele is associated with lower BMI in both men and women, indicating a possible protective effect against adiposity and obesity. Description: B.SC.(HONS)BIOMED.SCI. Thu, 01 Jan 2015 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/8862 2015-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/8632 Title: Lysophosphatidic acid receptor 1, monocyte count and risk of myocardial infarction Abstract: Environmental risk factors for myocardial infarction (MI) have been widely studied, yet the genetic risks associated with its development, although known to be present, are still not clearly defined. An association between atherosclerosis, MI and different blood parameter counts is known to exist. In this case-control study the influence of the rs551517 single nucleotide polymorphism (SNP) on blood parameter counts and incidence of MI was tested. Blood samples of cases with MI and age- and gender-matched controls from the Maltese population were used to measure blood parameter counts and for genotyping of the SNP. The rs551517 polymorphism was not associated with a risk of MI since OR for the homozygous mutant genotype was 0.9 (95% CI 0.5-1.4) and that for the heterozygous genotype was 1.2 (95% CI 0.9-1.6) when adjusting for age and gender. A risk for MI however was observed in smokers where the heterozygous genotype may have a 2-fold risk of MI, a risk not observed in non-smokers. When measuring the effect of the SNP on blood parameter counts, variations between genotypes were observed for white blood cells (WBC), platelet, eosinophil, reticulocyte and lymphocyte count. No effect of the rs551517 SNP on monocyte count was observed. This led to the conclusion that the rs551517 polymorphism is unlikely to have an effect on incidence of MI without the risk factor of smoking while an effect on a number of blood cell and platelet counts was observed. Description: B.SC.(HONS)BIOMED.SCI. Thu, 01 Jan 2015 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/8632 2015-01-01T00:00:00Z