OAR@UM Collection:/library/oar/handle/123456789/336072026-06-13T08:09:54Z2026-06-13T08:09:54ZIntroduction of antimicrobial susceptibility testing to Campylobacter species and sub-species./library/oar/handle/123456789/425402020-11-11T14:07:29Z2010-01-01T00:00:00ZTitle: Introduction of antimicrobial susceptibility testing to Campylobacter species and sub-species.
Abstract: Antibiotic resistance, particularly with the fluoroquinolones and macrolide
antibiotics, has now emerged globally with thermophilic campylobacters, including mainly
Campylobacter jejuni and Campylobacter coli, giving rise to concerns about how these
organisms have acquired such resistance characteristics, as well as consequences for
human and animal treatment.
Currently, Campylobacter is the leading enteropathogenic organism worldwide. Generally,
in animals this organism causes no harm, but in humans it causes campylobacteriosis with
a number of side effects including the Guillian-Barre virus.
It is contracted through many sources such as private reservoirs and unpasteurised milk but
mainly through ingested food.
Campylobacter is a zoonotic disease. Malta, having the smallest amount of broilers, when
compared to the rest of Europe, sports one of the highest percentages of Campylobacter
isolation from chicken carcasses.
This organism and the resistance associated with the strain are both transferred to humans.
Therefore, resistance acquired through the ingestion of animal feed with antibiotics (as
growth promoters), is transferred to humans through the zoonotic cycle. In order to
establish the Maltese setting when compared with Europe, a series of procedures were
carried out. Through the period of June 2008-June 2010, all Campylobacter strains (156
isolates) were collected from human stool samples received in the Bacteriology Laboratory
at Mater Dei Hospital which is the main Maltese General Hospital and also the only
teaching hospital in Malta. Each Campylobacter strain was subjected to a series of five
main antibiotics and the MICs of each was established. Through this, sensitive/resistance
patterns of each antibiotic was achieved and was compared with the European status.
Mean Inhibitory Concentration data was achieved using the E-strip method and
identification was done through conventional methods.
It was established that the Maltese picture is on the same baseline as that of Europe,
comparatively.
Through the results of the 156 isolates analyzed, evidence of the main predominance of
groups affected by this organism was established. The most age group affected was the
youngest group (0-10 years). In addition to this, the male sub-group showed a slightly
higher incidence when compared to the female group. Although the summer season
showed a peak of infectious incidence, a confluent incidence of infection was determined
throughout all months of the two year period of this study. When analyzing the sensitiveresistant
patterns, Erythromycin, Gentamicin and Meropenem showed quite a high
sensitivity in all strains. Even when a breakdown of each sub-species was analyzed,
Erythromycin remained one of the most sensitive antibiotics tested against. Although
Campylobacter coli showed much more resistance than Campylobacter jejuni,
Erythromycin, Gentamicin and Meropenem remained on the sensitive side, with
Ciprofloxacin and Tetracycline showing quite a pattern of resistance. Further analysis was
done to compare resistance between the two gender groups (male vs females) and also
between two main age-groups (0-15 years in one group and 16-above in another group).
Through this comparison, the younger age group (0-15 years) had the highest amount of
resistant strains when compared to the older generation. On the other hand, females
showed a lower sensitivity trend when compared to the male group. These results are of
great importance due to the fact that on a larger scale study, there may actually be a
definite trend of resistance between age groups and gender.
This data further emphasizes the great importance that Malta must be involved
wholeheartedly in surveys and any data collection studies that EFSA may request.
The objective of this study was to establish the sensitivity pattern of the two mam
antibiotics used for first line treatment which are mainly erythromycin and ciprofloxacin.
Due to the level of ciprofloxacin resistance noted in this study, erythromycin remains the
drug of choice in the suspicion of any Campylobacter infection. Erythromycin is still
mainly sensitive when compared to tetracycline, gentamicin and ciprofloxacin. Although,
erythromycin is still the ideal drug to use, one must keep in mind that Campylobacter
infections are generally self-limiting, and so over-use of this antibiotic is discouraged in
order to retain this sensitivity in erythromycin.
Description: M.SC.PHARMACOLOGY2010-01-01T00:00:00ZThe influence on the transcriptional regulation of chemokine receptor 3 (CCR3)/library/oar/handle/123456789/403552020-11-09T09:34:22Z2010-01-01T00:00:00ZTitle: The influence on the transcriptional regulation of chemokine receptor 3 (CCR3)
Abstract: Chemokine receptor 3 (CCR3), the major chemokine receptor expressed on
eosinophils, binds promiscuously to several ligands, mainly the eotaxin family of
chemokines which are up-regulated in inflammatory response. CCR3 expression in
airway epithelial cells has also been proposed to play an important role in airway
inflammation by promoting epithelial wound repair and subsequent tissue remodeling.
The promoter region of CCR3 gene has recently been characterized in the literature
and contains promoter elements which include a TAT A box and motifs for
transcription factors such as NF-KB, AP-l and GATA-I. In this study, we
investigated the effects of drugs whose action include an anti-inflammatory
component, and for which literature evidence for a transcriptional mechanism exists,
on the transcriptional regulation of CCR3 expression. pGL3E luciferase-based
reporter deletion constructs were generated for the 1.6kb CCR3 promoter region,
using standard cloning approaches in DH5α E. Coli cells. Each promoter construct
was transfected in a pulmonary epithelial cell line (A549) in microwell plate format
and stimulated with drugs (glucocorticoid dexamethasone, endogenous glucocorticoid
cortisol, and theophylline) in a dose dependent manner. This study has shown that
CCR3 transcription in cytokine unstimulated A549 cells can be regulated by
glucocorticoids and theophylline. A tri-phasic response (i.e. activating at low
concentration, repressive at medium concentration and activating at high
concentration) in CCR3 transcription response to dexamethasone was observed,
indicating a complex transcriptional regulatory mechanism. Dexamethasone induced
an nF-κB independent transcriptional repression of CCR3 in the unstimulated A549,
possibly involving the interaction of the activated glucocorticoid receptor with AP-l
in a trans-repressive molecular mechanism. Furthermore, CCR3 transcription
response to the endogenous glucocorticoid cortisol was significantly different than
that observed for dexamethasone. Our results have also shown that theophylline
significantly represses CCR3 transcription in the absence of glucocorticoids.
Description: M.SC.PHARMACOLOGY2010-01-01T00:00:00ZGender and access to medicines through the national health services/library/oar/handle/123456789/391562020-11-09T05:29:31Z2010-01-01T00:00:00ZTitle: Gender and access to medicines through the national health services
Abstract: Gender and access to medicines through the National health services
It is only recently that the issue of gender differences have prompted scrutiny
and generated interest within the medical field. In the past few decades, gender
differences in activities, goals and longevity were taken for granted, being quite
predictable, however today this situation has changed, making gender differences
more open to change (Verbrugge, 1985). The overall aim of the study is to identify
whether there is a gender bias in terms of access to NHS medicines in Malta, as per
diseases listed under the Fifth Schedule of the Social Security Act (Schedule V).
This study aimed at determining whether selected diseases listed on Schedule
V are more prevalent in males or in females. Specific literature searches to enable
gender sensitive assessment were conducted using Medline®, Pub med®, Google
scholar® and specific journals. To establish gender bias in terms of access to drugs
on Schedule V, the Maltese national formulary was retrieved, together with the
relevant drug use protocols. All information gathered was transferred in Microsoft
Excel® for further analysis. International consensus guidelines were retrieved from
NICE and SIGN. When not available, other international consensus guidelines were
consulted including the BNF 58. To investigate the possibility of gender bias in access
to drugs through omission of diseases as approved by Schedule V, a section of
gender specific drug treatable diseases from the ICD-10 was analyzed.
The results obtained clearly demonstrate higher gender prevalence in certain
diseases (e.g. angina, chronic rheumatoid arthritis and systemic sclerosis are more
prevalent in females; while congestive heart failure, Parkinson's disease,
schizophrenia and hepatic cirrhosis are more prevalent in males) and no gender
revalence in others (e.g. myocardial infarction and peptic ulcer disease). The
available literature does not always indicate the gender predominance. In some
instances this is not reported at all. Gender sensitive literature for Crohn's disease,
diabetes insipidus and Huntington's chorea is not available, while there is no clear
evidence to the gender prevalence for ulcerative colitis, chronic renal failure and
psoriasis. For the intent of this study, various international consensus guidelines
including SIGN, NICE and the BNF 58 were referred to and compared to the local
formulary and the pertinent protocols to evaluate what is available and approved for
use by protocol on Malta's national formulary with respect to the diseases listed on
Schedule V. No gender bias in terms of access of medications for conditions listed on
Schedule V was found. Following the analysis of gender specific drug treatable
conditions for ICD-10 resulted in a list of conditions which are omitted from Schedule
V, possibly creating a bias in terms of access of drugs for these conditions.
The analysis leads to the conjecture that most of the medications listed on the
national formulary are available and approved for use in diseases approved, as
recommended by the international consensus guidelines taken as a reference.
Consequently one can conclude that there seems to be no gender bias in terms of
access to medications for the diseases approved by the Schedule V. The specific
gender-related drug-treatable conditions of the genito-urinary system namely male
disorders of the genital organs, inflammatory diseases of the prostate and male
infertility, and female related disorders namely menopause, pelvic Inflammatory
disease, disorders of menstruation and female infertility are not conditions which
entitle patients to free medications through NHS.
Mental health and musculoskeletal disorders (osteoporosis) are conditions with
a female prevalence. This study deduced that these conditions are omitted from
Malta's official disease list for which entitlement to free medications is approved.
Looking at the percentage of employed women in relation to the positions occupied
and wages earned, one reaches the conclusion that a high percentage of the Maltese
female population is financially dependent. To add to this, another important
consideration to be made is the fact that females tend to outlive males, and that most
often they rely on males for economic resources, this means that a large percentage
of older women are at risk of dependency, isolation and poverty (WHO, 2003).
In light of these facts, together with the findings of this present study, it is
plausible to conclude that the fact that the above mentioned gender-related drug treatable conditions which are omitted for the list of diseases, for which free
medications are approved puts a large proportion of the Maltese female population at
risk. Most of the medications needed to manage or treat the female related conditions
mentioned earlier are already available for use through NHS; however these are not
approved for the conditions investigated in this analysis. This clearly indicates a bias
in terms of access for the female patient suffering from any of the mentioned
condition.
Description: M.SC.PHARMACOLOGY2010-01-01T00:00:00ZHigh resolution mapping of a DNA locus genetically linked to febrile seizures/library/oar/handle/123456789/387242020-11-06T09:47:39Z2010-01-01T00:00:00ZTitle: High resolution mapping of a DNA locus genetically linked to febrile seizures
Abstract: Epilepsy is regarded as a diverse family of disorders having in common an abnormally
increased predisposition to seizures. Approximately 70 per cent of all patients with
epilepsy lack an obvious symptomatic cause, and therefore are presumed to have a
predominantly genetic basis for their condition. To date, a number of mutations in ion
channel and neuroreceptor constituent genes have been identified in some syndromes with
clear Mendelian inheritance. Moreover, various studies have shown that epilepsy
syndromes tend to aggregate in families. The main aims of this study were to narrow down
a previously identified linkage region on chromosome 20 by performing a linkage study
using short tandem repeat markers, and to identify and sequence two genes found within
this region which could be predisposing the family to the familial febrile seizures
phenotype.
This study was carried out on a Maltese three generation family having seven members
affected by febrile seizures. All thirteen family members were genotyped for seven short
tandem repeat markers found in the linkage region on chromosome 20 previously
identified in a study conducted by Cassar in 2008. These markers were spaced at
approximately 2cM from each other, using the deCODE map as a reference. Following
genotyping, linkage analysis was performed and the two candidate genes chosen from the
newly narrowed region were NKAIN4 and HRH3. Primer design for the exon/intron
junctions of these two genes was carried out using NCBI's Primer-Blast designing tool and
the respective reference sequences. Samples from an affected individual and a non-affected
individual were sequenced. Subsequently the sequences obtained were first compared to
each other and then to their reference sequences to determine any significant differences.
Analysis of DNA from affected family members reduced the previously identified linkage
region to about 5cM on chromosome 20q13.3. A maximum multipoint LOD score of 2.67
was obtained when 0.9 penetrance was used. This score is suggestive evidence for linkage.
The identified locus has never been associated to familial febrile seizures syndrome before.
This region spans a total of 84 genes, of which NKAIN4 and HRH3 were selected for
further analysis. These two genes have been previously associated to epilepsy or seizures
and are both expressed in the central nervous system. In fact, five different single
nucleotide polymorphisms were found on analysis of the sequences obtained from the
affected and non-affected individuals. These variations were characterised using the
relevant online databases, however for various reasons none of these point mutations
seemed to be immediately implicated in the formation of the febrile seizures observed in
the family.
Even though four of the observed single nucleotide polymorphisms in NKAIN4 were not
found in the exons of the gene, this is not conclusive evidence that they do not confer a
disease risk to the family. A literature review shows that heterogeneity in untranslated
regions of a gene is likely to have an impact on protein expression in an individual,
possibly leading to disease. This difference in protein expression may happen through
various mechanisms, namely polymorphisms in micro RNA targets and disruption of
splicing, leading to unstable mRNAs and defective protein structure.
This project has identified a novel locus associated to the familial febrile seizures
syndrome in a Maltese family and contributes to a better understanding of the condition.
Discovery of gene mutations that predispose to epilepsies have led to the possibility of
using gene therapy in the hope of overcoming common problems observed with the
currently available drug therapy, especially in cases of pharmacoresistance. It is evident
that the knowledge gained through such genetic studies can be applied to the search for
improved antiepileptic drugs.
Description: M.SC.PHARMACOLOGY2010-01-01T00:00:00Z