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Optimal utilization of gamma camera time in Tc-99m MDP bone scintigraphyJawa, Zabah Muhammad 03 1900 (has links)
Thesis (MScMedSc (Medical Imaging and Clinical Oncology. Nuclear Medicine))--University of Stellenbosch, 2007. / Introduction: Whole body bone scintigraphy with Tc-99m MDP is able to provide a survey of the entire skeleton. The question arises if it is mandatory to perform a whole body bone scan in all patients, irrespective of the clinical indication. The aim of this study is to determine the implications of performing limited imaging in patients who had whole body bone scan for various clinical patholgy with Tc-99m MDP, in order to determine if limited imaging would be acceptable in selected pathologies. This may enable gamma camera time to be optimally utilized in units with limited facilities.
Materials and Methods: Reports of 3015 patients with various clinical pathologies who had whole body bone scans with Tc-99m MDP in our department from January 2002 to December 2004 were retrospectively reviewed. The presence of pathologic radiotracer uptake was analyzed in order to establish the pattern of distribution. Clinically significant skeletal lesions were classified according to the anatomical regions where they were located viz; skull (including the neck), axial skeleton (including the pelvis and shoulders) and limbs.
Results: Our results showed that in patients with lung cancer, soft tissue sarcoma, and myeloma, there was an error in more than 25% of patients when limited imaging was performed. In patients with cancer of the breast, prostate, kidney, gastrointestinal system, and reproductive system and lymphoma there is an error in less than 5% of patients when limited imaging is employed. For
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patients with more localized musculoskeletal disorders such as suspected stress fractures, complicated joint prosthesis and avascular necrosis of the femur head, regional imaging of the area of pathology showed a percentage error of less than 6%.
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Investigations of Renin-Angiotensin Aldosterone System (RAAS) genes in hypertrophy in hypertrophic cardiomyopathy (HCM) founder familiesCloete, Ruben Earl Ashley 03 1900 (has links)
Thesis (MScMed)--Stellenbosch University, 2008. / ENGLISH ABSTRACT: In hypertrophic cardiomyopathy (HCM), an autosomal dominant disorder, hypertrophy is variable
within and between families carrying the same causal mutation, suggesting a role for modifier genes.
Associations between left ventricular hypertrophy and left ventricular pressure overload suggested
that sequence variants in genes involved in the Renin-Angiotensin Aldosterone System (RAAS) may
act as hypertrophy modifiers in HCM, but some of these studies may have been confounded by,
amongst other things, lack of adjustment for hypertrophy covariates.
To investigate this hypothesis, twenty one polymorphic loci spread across six genes (ACE1, AGT,
AGTR1, CYP11B2, CMA and ACE2) of the RAAS were genotyped in 353 subjects from 22 South
African HCM-families, in which founder mutations segregate. Genotypes were compared to 17
echocardiographically-derived hypertrophic indices of left ventricular wall thickness at 16 segments
covering three longitudinal levels. Family-based association was performed by quantitative
transmission disequilibrium testing (QTDT), and mixed effects models to analyse the X-linked gene
ACE2, with concurrent adjustment for hypertrophy covariates (age, sex, systolic blood pressure (BP),
diastolic BP, body surface area, heart rate and mutation status).
Strong evidence of linkage in the absence of association was detected between polymorphisms at
ACE1 and posterior and anterior wall thickness (PW and AW, respectively) at the papillary muscle
level (pap) and apex level (apx). In single-locus analysis, statistically significant associations were
generated between the CYP11B2 rs3097 polymorphism and PW at the mitral valve level (mit) and
both PWpap and inferior wall thickness (IW)pap. Statistically significant associations were
generated at three AGTR1 polymorphisms, namely, between rs2640539 and AWmit, rs 3772627 and
anterior interventricular septum thickness at pap and rs5182 and both IWpap and AWapx.
Furthermore, mixed effects model detected statistically significant association between the ACE2
rs879922 polymorphism and both posterior interventricular septum thickness and lateral wall
thickness at mit in females only.
These data indicate a role for RAAS gene variants, independent of hypertrophy covariates, in
modifying the phenotypic expression of hypertrophy in HCM-affected individuals. / AFRIKAANSE OPSOMMING: Hipertrofiese kardiomiopatie (HCM), ‘n autosomale dominante afwyking, toon hoogs variërende
hipertrofie binne en tussen families wat dieselfde siekte-veroorsakende mutasie het, hierdie dui op
die moontlike betrokkenheid van geassosieerde modifiserende gene. Assosiasies tussen linker
ventrikulêre hipertrofie en linker ventrikulêre druk-oorlading stel voor dat volgorde variasies in gene
betrokke in die Renin-Angiotensin Aldosteroon Sisteem (RAAS) mag optree as hipertrofie
modifiseerders in HCM. Sommige van hierdie soort studies is egter beperk omdat hulle nie
gekompenseer het vir kovariante van hipertrofie nie.
Om hierdie hipotese te ondersoek, is die genotipe bepaal by een-en-twintig polimorfiese lokusse,
verspreid regoor ses RAAS gene (ACE1, AGT, AGTR1, CYP11B2, CMA and ACE2), in 353
kandidate vanuit 22 Suid-Afrikaanse HCM-families in wie stigter mutasies segregeer. Genotipes was
vergelyk met 17 eggokardiografies afgeleide hipertrofiese indekse van linker ventrikulêre wanddikte
by 16 segmente wat oor drie longitudinale vlakke strek. Familie-gebaseerde assosiasies was
bestudeer deur kwantitatiewe transmissie disequilibrium toetsing (QTDT) en gemengde effek
modelle om die X-gekoppelde geen ACE2 te analiseer, met gelyktydige kompensasie vir hipertrofie
kovariate (ouderdom, geslag, sistoliese bloed druk (BP), diastoliese BP, liggaamsoppervlak area,
hartritme en mutasie-status).
Sterk indikasies van koppeling in die afwesigheid van assosiasie is waargeneem tussen ACE1
lokusse en posterior wanddikte (PW) asook anterior wanddikte (AW) by die papillêre spier vlak
(pap) en die apeks vlak (apx). In enkel-lokus analises is statisties-betekenisvolle assosiasies gevind
tussen die CYP11B2 rs3097 polimorfisme en PW by die mitraalklep vlak (mit) en beide die PWpap
en inferior wanddikte (IW)pap. Statisties-betekenisvolle assosiasies was verder gevind by drie
AGTR1 polimorfismes, naamlik, tussen rs2640539 polimorfisme en AWmit, rs3772627 en die
anterior interventrikulêre septumdikte (aIVS) by die pap en rs5182 by beide die IWpap en AWapx.
Gemengde-effek modelle het verder assosiasies aangetoon tussen die ACE2 rs879922 polimorfisme
en die posterior interventrikulêre septumdikte en die laterale wanddikte by die mit, slegs in vrouens.
Hierdie data dui op ‘n kovariaat-onafhanklike rol vir RAAS genetiese variante in die modifisering
van die fenotipiese uitdrukking van hipertrofie in HCM-geaffekteerde individue.
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Nucleotide sequence variation and expression levels of TP53 in cancers of the upper gastro-intestinal tractBarnard, Desire 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The work presented in this thesis deals with the association between cancers of
the upper gastro-intestinal tract and the tumor suppressor gene, TP53, and can
be divided into three parts: (i) the analysis of the mutational spectrum of TP53
with respect to laryngeal cancer, (ii) the analysis of the mutational spectrum of
TP53 with respect to esophageal cancer and (iii) the analysis of TP53
transcriptional levels in esophageal cancer.
Laryngeal cancer (LC) is the 6th most common cancer in the world and the 2nd
most common respiratory cancer, with approximately 500 000 new cases per
annum detected worldwide. Over the last few years, LC has become
increasingly prevalent within the Coloured Community of the Western Cape. The
mechanisms of tumorigenesis in LC remain unknown, although smoking and
alcohol consumption are considered to be major risk factors. Mutations within
the gene TP53 have been strongly implicated as playing a role in cancer
development, as they are frequently found in several cancer types. We therefore
screened exons 5 - 8 of TP53 for mutations in DNA from tumor biopsies (n=44)
and blood samples (n=42) from Coloured LC patients, using polymerase chain
reaction - single strand conformation polymorphism (PCR-SSCP) analysis and
direct sequencing. Blood samples from a healthy, matched control group (n=40)
were included in the study as controls. Significant correlations were found
between the occurrence of LC and age and smoking, whereas daily meat
consumption was a possible protective factor. In tumor-derived samples,
mutations were found in 3 of the exons under investigation, representing 25% of
the samples. The mutations were unique to the tumor biopsies, indicating a
somatic origin for mutations. The data confirms that the region between codons
175 and 273 of TP53 is a mutational hotspot for cancers in general. This study
reports 6 novel mutations within this same region. Esophageal cancer (EC) has a very high incidence in South Africa, relative to the
rest of the world, and is particularly common amongst the Black Transkei
population. The goal of this study was to determine whether there are
differences in the TP53 mutational pattern observed in the Coloured Western
Cape community as compared to that observed in the Black Transkei community.
This required the analysis of the molecular structure of TP53, specifically exons 5
- 8, in a group of Coloured EC patients (n=44) treated at Tygerberg Hospital,
Cape Town, South Africa. DNA obtained from tumor biopsies and blood (from
patients) as well as from apparently healthy surrounding tissue was screened via
PCR-SSCP and direct sequencing analysis. Only 4 nucleotide changes were
observed from a total of 124 sequences obtained, of which two were novel to
esophageal squamous cell carcinoma. These 4 nucleotide alterations were
found only within the tumor biopsy sample set, representing 9% of the tumors
investigated. This study revealed that the mutational spectrum of TP53 within
the Coloured population of the Western Cape greatly differs from that of the
Black community of the Transkei. This suggests that a different set of etiological
factors are involved in the tumorigenic process for each of these distinct
geographical communities, which is the subject of an epidemiological study
undertaken by the MRC.
The final part of this thesis deals with the quantification and comparison of TP53
transcription levels in esophageal cancer tumor tissue to the TP53 levels in
healthy esophageal tissue obtained from patients from a unique geographical
and ethnic background. The cohort used in this study consisted of Coloured
patients (n=2) treated at Tygerberg Hospital. The LightCycler system was
implemented in order to try to accurately quantify TP53 mRNA levels.
Unfortunately, the desired results were unattainable due to unforeseen difficulties
encountered during the study. These difficulties included the insufficient
preservation of samples for RNA based studies. Several recommendations were
made concerning future similar studies, including an improved planning strategy
as well as the employment of an RNA stabilizing agent. Additionally, a few important contributions were made through this study, including the design and
optimization of TP53 primers specifically intended for future RNA studies. These
primers would enable the identification of the presence of TP53 RNA species as
well as the absence of DNA contamination in a single PCR amplification step.
Other contributions include the development of a well-optimized RNA extraction
method for the extraction of RNA from tough tissues (such as the human
esophageal tissue used in this study). This method makes the extraction of large
quantities of RNA from small amounts of tough tissue types possible.
In conclusion, this study has made a significant contribution to the field of cancer
research, by shedding light on the TP53 mutational spectrum with regards to
laryngeal as well as esophageal cancer in a population unique to the Western
Cape.
The first part of this thesis has been published in Cancer Genetics and
Cytogenetics (Barnard, D., K. Lehmann, E.G. Haal, P.O. van Heiden, and l.C.
Victor. 2003. The spectrum of mutations in TP53 in laryngeal cancer patients
from a high-incidence population shows similarities to many of the known
mutational hotspots. Cancer Genetics and Cytogenetics 145:126-132), of which
a copy can be found in Appendix I. This work has also been presented (by D.
Barnard) at an international conference entitled "Cancer of the Esophagus and
Gastric Cardia: From Gene to Cure", held in Amsterdam, the Netherlands during
the period 13 - 15 December 2002. / AFRIKAANSE OPSOMMING: Die werk wat in hierdie tesis voorgelê word handel oor die assosiasie tussen
kankers van die boonste gastrointestinale weg en die tumor suppressor geen,
TP53, en kan in 3 dele gedeel word, (i) die analise van die mutasiespektrum van
TP53 in laringiale kanker (LK), (ii) die analise van die mutasiespektrum van TP53
in slukderm kanker (SK) en (iii) die analise van die transkripsievlakke van TP53
in SK.
Laringeal kanker (LK) is die 6de algemeenste kanker in die wêreld en die 2de
algemeenste respiratoriese kanker, met "n benaderde 500 000 nuwe gevalle
jaarliks wêreldwyd. Oor die afgelope paar jare het LK "n toenemende probleem
geraak, veral in die Kleurling gemeenskap van die Wes Kaap. Die meganismes
van die tumorvorming in LK is onbekend, alhoewel rook-en alkoholgebruik
vername risiko faktore is. Die voorkoms van mutasies in TP53 is verskeie kere
aangetoon in verskillende kanker tipes en daar word vermoed dat dit "n rol speel
in tumorvorming. In hierdie studie is dus na mutasies in eksons 5 - 8 van TP53
gesoek in tumor biopsie weefsel (n=44) en bloed isolate (n=42) van Kleurling LK
pasiënte d.m.v. polimerase ketting reaksie - enkelstring konformasie
polimorfisme (PKR-ESKP) analisering en direkte volgorde bepaling. Bloed
monsters van "n vergelykbare groep (n=40) is ook in die studie ingesluit as "n
kontrole. Betekenisvolle positiewe korrelasies is gevind tussen die voorkoms van
LK en ouderdom sowel as rook. Daarmee saam is daaglikse vleisinname as
potensiële beskermende faktor gevind. In tumor biopsies is mutasies in 3 van
die ondersoekte eksons gevind, wat 25% van die biopsie monsters
verteenwoordig. Hierdie mutasies is uniek aan die tumor biopsie weefsels en dui
op "n somatiese oorsprong van mutasies. Hierdie bevindinge bevestig dat die
gedeelte tussen kodons 173 - 273 van TP53 "n hipermuteerbare gebied
geassosieer met kankers is. Hierdie studie bevestig 6 nuwe mutasies.
Daar is 'n hoë insidensie van slukderm kanker (SK) in Suid Afrika relatief tot die
res van die wêreld. Hierdie soort kanker word veral gevind by die Swart
populasie van die Transkei. Die doel van hierdie studie was om verskille tussen
die TP53 mutasie patroon van die Kleurling gemeenskap van die Wes Kaap en
die Swart gemeenskap van die Transkei te vergelyk. Hiervoor is die molekulêre
struktuur van TP53, veral eksons 5 - 8, in 'n groep Kleurling SK pasiënte (n=42)
wat behandel is by Tygerberg Hospitaal, Kaapstad, Suid Afrika, geanaliseer.
Analisering is gedoen deur DNS van tumor, bloed en ook oënskynlike gesonde
aangrensende weefsel van dieselfde pasiënte te onderwerp aan PKR-ESKP
analise en direkte volgorde bepaling. Slegs 4 nukleotied veranderings is gevind
in 124 volgorde bepalings, waarvan 2 nuwe veranderings is in SK. Hierdie 4
nukleotied veranderinge verteenwoordig 9% van al die tumors wat ondersoek is
in die studie. Hierdie studie bewys dat die mutasiespektrum van TP53 in die
Kleurling gemeenskap van die Wes Kaap grootliks verskil van die Swart
gemeenskap van die Transkei. Dit impliseer dat verskillende etiologiese faktore
moontlik 'n rol mag speel op die tumorvormingsproses in die 2 afsonderlike
geografiese gemeenskappe. Hierdie is die onderwerp van 'n epidemiologiese
studie wat deur die MNR onderneem word.
Die laaste deel van hierdie tesis handel oor die kwantifisering en vergelyking van
TP53 transkripsievlakke in SK tumor weefsel teenoor TP53 vlakke in gesonde
slukderm weefsel van pasiënte in 'n unieke geografiese en etniese agtergrond.
Die studie populasie in hierdie projek het bestaan uit Kleurling pasiënte (n=2) wat
by Tygerberg hospitaal behandel is. Die "LightCycler" sisteem is gebruik vir die
akkurate kwantifisering van TP53 boodskapper RNS vlakke. Ongelukkig is die
verlangde resultate nie gekry nie as gevolg van onvoorsiene probleme wat
ondervind is tydens die studie. Hierdie probleme sluit in die onvoldoende
preserv RNS studies. Hierdie inleiers maak dit nou moontlik om die teenwoordigheid van
TP53 RNS spesies sowel as die afwesigheid van DNS kontaminasie in een PKR
amplifikasie stap te kan identifiseer. 'n Ander belangrike bydrae is die
ontwikkeling van 'n goed geoptimaliseerde RNS ekstraksie metode vir moeilike
starre weelfsel tipes (soos menslike slukderm weefsel in hierdie studie) en maak
die ekstraksie van groot hoeveelhede RNS uit klein hoeveelhede van moeilik
hanteerbare weefsel tipes moontlik.
Om saam te vat, hierdie studie het betekenisvolle bydraes gemaak tot die veld
van kankernavorsing deur die ontrafeling van die TP53 mutasiespektrum in beide
laringeale sowel as slukderm kanker, in 'n populasie uniek aan die Wes Kaap.
Die eerste deel van hierdie tesis is gepubliseer in Cancer Geneties and
Cytogenetics (Barnard, D., K. Lehmann, E. G. Hoal, P. D. van Heiden, and T. C.
Victor. 2003. The spectrum of mutations in TP53 in laryngeal cancer patients
from a high-incidence population shows similarites to many of the known
mutational hotspots. Cancer Genetics and Cytogenetics 145: 126-132) en 'n
afskrif van die artikel is ingesluit in Appendix I. Hierdie werk is ook voorgedra
(deur D. Barnard) by 'n internasionale kongres getiteld "Cancer of the
Esophagus and Gastric Cardia: From Gene to Cure", wat in Amsterdam,
Nederland gehou is gedurende 13 - 15 Desember 2002
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Mutation screening of candidate genes and the development of polymorphic markers residing on chromosome 19q13.3, the progressive familial heart block I gene search areaMakubalo, Zola 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: Progressive familial heart block type I (PFHBI) is a cardiac ventricular conduction disorder of
unknown cause associated with risk of sudden death, which has been described in several
South African families. Clinically, PFHBI is characterised by right bundle branch block on
ECG, which may progress to complete heart block, necessitating pacemaker implantation.
The disease shows an autosomal dominant pattern of inheritance with evidence of genetic
anticipation. Using genetic linkage analysis, the PFHBI-causative gene was mapped to a 10
eentimorgan (cM) gene-rich area of chromosome (C) 19q13.3, which has, subsequently, been
reduced to 7cM by fine mapping with polymorphic dinucleotide (CA)n short tandem repeat
(STR) markers. Several attractive candidate genes, including muscle glycogen synthase
(GSY 1) and histidine-rich calcium binding protein (HRC), lie within this region.
The aim of the present study was two-fold: 1) to identify and characterise tetranucleotide
(AAAT)n STRs within the PFHBI critical region that could be developed as polymorphic
markers for use in genetic fine mapping and 2) to screen selected regions of GSY 1and HRC,
positional candidate genes, for the presence ofPFHBI-causing mutation(s).
Cosmids harbouring CI9q13.3 insert DNA were screened for the presence of (AAAT)n STRs
by dot blot and Southern blot hybridisation using a radiolabelled (AAAT)lO oligonucleotide
probe. To characterise the harboured (AAAT)n STRs, the positively hybridising fragments
identified by Southern blot were sub-cloned, sequenced and primers designed from the unique
repeat-flanking sequences. These primers were used to genotype the (AAAT)n repeat locus to
assess its polymorphic nature in a panel of unrelated individuals. Alternatively, vectorette
PCR, a rapid method of identifying repeat sequences and obtaining the flanking sequences in
large inserts, was employed to develop polymorphic markers from the positively hybridising
clones. Selected exons of GSY1 and HRC were screened for the presence of potentially
disease-causing mutations by PCR-SSCP analysis and direct sequencing, respectively, in
PFHBI-affected and unaffected family members.
Of the available cosmid clones that gave strong signals on dot blot and Southern blot
hybridisation, three, 29395, 24493 and 20381, were located within the critical PFHBI area
and were used for marker development. An interrupted (AAAT)n repeat motif (n less than 5)
was identified in cosmid 29395, however, the repeat locus was not polymorphic in the tested
population. No (AAAT)n motif, single or repeated was observed in the partial sequence of the sub-cloned fragment of cosmid 24493. Using vectorette peR, no repeated (AAAT)n motif
was identified on sequencing the generated products in either cosmid 24493 or 2038l.
However, diffuse single AAAT motifs were detected in both cosmids. Exons 4, 5, 11, 12 and
16 of GSY 1, containing domains that are conserved across species, and the conserved eterminus-
encoding exons 2-6 of HRC were selected for screening for potential PFHBI-causing
mutation(s). However, no sequence variations were detected.
The interrupted (AAAT)n repeat identified in cosmid 29395 was not polymorphic, which
confirmed reports that complex repeats, especially those containing AAAT motifs of less than
6 repeats, are not polymorphic. One possible explanation for the absence of a repeated AAAT
motif in cosmids 24493 and 20381, which both gave positive hybridisation signals, is that the
low annealing temperature of the AfT -rich repeat-anchored primers used in vectorette peR
may have resulted in transient annealing to the diffuse single AAAT motifs detected on
sequencing. The screened regions of candidate genes GSYI and HRC were excluded from
carrying the disease-causing mutation(s).
The availability of new sequence data generated by the Human Genome Project will influence
future strategies to identify the PFHBI gene. Electronic searches will allow identification of
STR sequences for development of polymorphic markers and gene annotation will allow
selection of new candidate genes for mutation screening. / AFRIKAANSE OPSOMMING:
Sien volteks vir opsomming
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The effects of fumonisins on sphinganine and sphingosine levels in hepataocyte cultures, experimental animals and humansVan der Westhuizen, Liana 03 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT:
Please see fulltext for abstract / AFRIKAANSE OPSOMMING:
Sien asb volteks vir opsomming
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Characterisation of a high copy number mutant pAL5000 origin of replicationJansen, Yvette 12 1900 (has links)
Thesis (MScMedSc)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: The plasmid pAL5000 is a mycobacterial plasmid isolated from Mycobacterium
fortuitum. It is a low copy number plasmid, which replicates in both fast growing (e.g.
M. smegmatis) and slow growing (e.g. M. bovis BCG) mycobacteria. Most
mycobacterial-E. coli shuttle vectors utilise the pAL5000 origin of replication. The
minimum replicon consists of ORF1 (RepA), ORF2 (RepB) and the origin of
replication.
Dr W.R. Bourn created an E. coli-mycobacterial vector based on the pAL5000 origin
of replication (pORI) and then subjected it to semi-random mutagenesis. A high copy
number mutant was identified (pHIGH) and the causative mutation was tentatively
identified as a 3bp deletion situated just upstream of repB. This work describes the
further characterisation of the mutant plasmid.
Firstly, it was shown by retransforming M. smegmatis with both the original and
mutant plasmids (pORI and pHIGH), that the mutation causing the increased copy
number was plasmid-encoded and not on the chromosome. Following this, it was
demonstrated by simple subcloning of the region that carries the 3 bp deletion, that
other pAL5000-based vectors could be converted to high copy number. In addition to
this, the subcloned region was sequenced and the nature of the mutations was
confirmed. The subcloning experiment confirmed that the 3bp deletion caused the
high copy number phenotype.
Following this, the exact copy number of pHIGH and the relative increase in copy
number was determined. From this, the copy number of pORI could also be
determined. The plasmid pHIGH has a copy number of approximately 54, compared
to the 8 of pORI (a relative increase by a factor of 7).
Because it is important for researchers to know the characteristics of the vectors that
they use, especially the influence it will have on its host, stability tests and growth
curves were also performed. It was seen that the higher copy number did not
markedly increase the stability, however, this is because pORI is already extremely, and unexpectedly, stable in the host M. smegmatis. According to the growth curves,
the increased copy number has little effect on the growth of the host M. smegmatis.
Possible mechanisms for the increased copy number were then investigated. By using
a promoter probe vector, the possible existence of a promoter situated between the
two open reading frames of pAL5000 (repA and repB) was investigated. It was
thought that the mutation might have created, or changed an existing promoter,
situated between repA and repB. The results showed, however, that in both pORI and
pHIGH there might be a very weak promoter upstream of repB, but the mutation did
not cause any change that was measurable by the method that was used.
A further possibility was that the mutation caused a change in the RNA secondary
structure, which might then have an effect on the translational efficiency of RepB. It
was found that the 3bp deletion in pHIGH causes a change in the local RNA
secondary structure around the ribosomal binding site and the start codon, when
compared to pORI (wild type). This change may cause the translation initiation rate of
RepB to be different between pHIGH and pORI. Ultimately it would lead to a
different ratio of RepA and RepB in the cell. / AFRIKAANSE OPSOMMING: Die plasmied pAL5000 is ‘n mikobakteriele plasmied wat vanuit Mycobacterium
fortuitum gei'soleer is. Dit is ‘n lae kopie-getal plasmied wat in beide vinnig groeiende
(bv. M. smegmatis) en stadig groeiende (bv. M. bovis BCG) mikobakteriee kan
repliseer. Die meeste mikobakteriele-E. coli shuttle vektore gebruik die pAL5000
oorsprong van replisering. Die minimum replikon bestaan uit ORF1 (RepA), ORF2
(RepB) en die oorsprong van replisering.
Dr. W.R. Bourn het ‘n E. coli-mikobakteriele vektor gemaak wat gebaseer is op die
pAL5000 oorsprong van replisering (pORI), en dit onderwerp aan semi-random
mutagenese. ‘n Hoë kopie-getal mutant is gei'dentifiseer (pHIGH) en die mutasie
hiervoor verantwoordelik was tentatief gei'dentifiseer as ‘n 3bp delesie, net stroomop
van repB. Die projek beskryf die verdere karakterisering van die mutante plasmied.
Eerstens, deur M. smegmatis te hertransformeer met die plasmied DNA (pORI en
pHIGH), is dit bewys dat dit mutasie wat die toename in kopie-getal veroorsaak, deur
die plasmied gekodeer word, en dat dit nie ‘n mutasie op die chromosoom is nie.
Hierna is dit deur eenvoudige subklonering bewys dat die gedeelte wat die 3bp delesie
dra, ander pAL5000-gebaseerde vektore ook kan verander in ‘n hoër kopie-getal. Die
sub-klonerings eksperiment het ook bewys dat die 3 bp delesie die oorsaak is vir die
hoë kopie-getal fenotipe.
Volgende is die presiese kopie-getal van pHIGH en die relatiewe toename in kopiegetal
bepaal. Die kopie-getal van pORI kon vanaf hierdie data bepaal word. Die
plasmied pHIGH het ‘n kopie-getal van ongeveer 54 in M. smegmatis, in vergelyking
met die 8 van pORI (‘n relatiewe toename met ‘n faktor van 7).
Aangesien dit vir navorsers belangrik is om die eienskappe van die vektore wat hulle
gebruik, te ken, en veral die invloed wat dit op die gasheer sal hê, is stabiliteits toetse,
en groeikurwes gedoen. Die hoër kopie-getal het nie die stabiliteit werklik verbeter
nie, maar dit is omdat pORI alreeds uiters stabiel is in die gasheer M. smegmatis. Volgens die groeikurwes het die toename in kopie-getal ‘n minimale effek op die
groei van die gasheer M. smegmatis.
Moontlike meganismes vir die hoër kopie-getal is ook ondersoek. Die moontlike
bestaan van ‘n promoter tussen die twee oop-leesrame van pAL5000 (repA en repB)
is ondersoek deur gebruik te maak van ‘n “promoter probe” vektor. Die mutasie kon
moontlik ‘n promoter geskep het, of ‘n bestaande een tussen repA en repB verander
het. Die resultate het gewys dat daar in beide pORI en pHIGH moontlik ‘n baie swak
promoter stroomop van repB is, maar die mutasie het nie enige veranderinge
veroorsaak wat meetbaar was met die metode wat gebruik is nie.
‘n Verdere moontlikheid was dat die mutasie ‘n verandering in die RNA sekondere
struktuur kon veroorsaak het, en dit mag ‘n effek hê op die translasie effektiwiteit van
RepB. Daar is gevind dat, in vergelyking met pORI, het die 3bp delesie in pHIGH ‘n
verandering in die lokale RNA sekondere struktuur rondom die ribosomale bindings
posisie en die begin-kodon veroorsaak. Die verandering mag veroorsaak dat die
translasie inisiasie tempo van RepB verskillend is vir pORI en pHIGH. Uiteindelik sal
dit lei tot ‘n heeltemal ander verhouding van RepA en RepB in die sel.
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Obsessive-compulsive disorder : defining the role of gene-based variants and immunological factorsKinnear, Craig 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2001. / ENGLISH ABSTRACT:
Please see fulltext for abstract / AFRIKAANSE OPSOMMING:
Sien asb volteks vir opsomming
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Alternative insulin mitogenic signaling pathways in immature osteoblast cell linesLangeveldt, Carmen Ronel 03 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: Insulin is a mitogen for many cells and commonly signals through the classical, mitogenic Raf-
MEK-ERK or metabolic PB-kinase pathways. Insulin deficiency or type I diabetes causes
severe osteopenia. Obese patients with type II diabetes or insulin resistance, a disease associated
with defective insulin signaling pathways and high levels of circulating insulin, have increased
or normal bone mineral density. The question of whether hyperinsul inemia preserves bone mass
is frequently raised. However, there is still a lot of controversy on the role of insulin as an
osteoanabolic agent and this question still remains unanswered. A critical role for insulin
signaling in bone building osteoblasts has recently been demonstrated with IRS-l knock-out
mice. These mice developed low-turnover osteopenia due to impaired proliferation and
differentiation, stressing the importance of osteoblastic IRS-l for maintaining normal bone
formation.
In the present study it was found that insulin does function in vitro as an osteoblast mitogen.
This was illustrated in three relatively immature osteoblast (MBA-15.4, -15.6 mouse and MG-
63 human) cell lines, which responded to insulin with significant increases in proliferation. In
the MBA -15.4 preosteoblasts insulin stimulation of proliferation was comparable to the welldescribed
mitogen, TPA. The UMR-I06 cell line expresses markers of differentiated
osteoblasts, and was much less responsive to insulin treatment. The difference in proliferative
potential may be due to differences between spontaneously transformed cell lines, or the stage
of cell differentiation.
UOI26, a MEKI/2 inhibitor and wortmannin, a PB-kinase inhibitor, were used to investigate the
pathway used by insulin to signal and activate ERK and osteoblast proliferation. In MBA-15.4
mouse preosteoblasts, GF-containing FCS was completely dependent on MEK for DNA
synthesis. In contrast, in both MBA-15.4 and more mature MBA-15.6 osteoblasts, insulininduced
proliferation was resistant to the inhibitors alone or in combination. Higher MEKinhibitor
concentrations had no effect, and proliferation was also increased by the inhibitors in
several experiments. This indicated that the classical, insulin mitogenic pathway was not
involved in MBA-15.4 proliferation. Wortmannin had no effect on either insulin- or 20% FCSstimulated
proliferation, but inhibited activation of Akt/PKB, the metabolic downstream target
of PI3-kinase. Insul in signal ing to ERK was both MEK-and PI3-kinase- dependent, but this had
no effect on proliferation. In contrast, FCS-stimulated ERK activation and proliferation was
almost completely dependent on MEK-ERK activation. Proliferative signaling in the MG-63 human osteoblastic cell line in response to insulin was
partially dependent on MEK and partially dependent on PB-kinase. In contrast, signaling in
response to the phorbol ester, TPA, was partially dependent on PI3K but totally dependent on
MEK-ERK. This indicates that the signal converges on ERK, suggesting the involvement of a
PB-kinase upstream of a dominant MEK-ERK pathway. The differences found here between
mouse and human insulin mitogenic signaling pathways indicate that there may be species
differences between osteoblast signaling pathways, with mouse cells being independent and
human cells being dependent on MEK for DNA synthesis in response to insulin.
The effects of glucocorticoids on insulin mitogenic signaling in osteoblasts were also
investigated, because chronic long-term steroid use results in excessive bone loss. The PTP
inhibitor, sodium orthovanadate, reversed GC-impaired TPA- and FCS- induced proliferation in
MBA-1SA and MG-63 preosteoblasts. PTPs, such as SHP-l and PTP-IB, dephosphorylate and
inactivate phosphorylated kinases. Both SHP-l and PTPlB associated with kinases in the
mitogenic signaling cascade of MBA-lS.4 preosteoblasts growing rapidly in 10% FCS. Further,
SHP-I co-irnmunoprecipitated with active, tyrosine phosphorylated ERK, which may indicate
that it can dephosphorylate and inactivate ERK. However, since the MEK-ERK or PB-kinase
pathways are not important in insulin-induced proliferation in mouse osteoblasts, the PTPs are
unlikely to be role players in the negative regulation of this signaling pathway. This was
confirmed by the finding that vanadate was unable to reverse GC-induced decreases in insulinstimulated
DNA synthesis. This suggests that vanadate-sensitive PTPs may not be important in
the negative regulation of insulin-induced mouse osteoblast proliferation, and provides further
evidence of a novel insulin mitogenic pathway in the MBA-lSA but not MG-63 osteoblastic
cell line. / AFRIKAANSE OPSOMMING: Insulien is 'n mitogeen vir baie selle en gelei na binding aan die insulien reseptor, intrasellulêre
seine via die klassieke, mitogeniese Raf-MEK-ERK of die metaboliese PB-kinase
seintransduksie pad. 'n Insulien gebrek of tipe I diabetes veroorsaak osteopenie. Vetsugtige
pasiënte met insulien weestandigheid of tipe II diabetes, 'n siekte wat geassosieer word met
foutiewe insulien seintransduksie en hoë vlakke van sirkuierende insulien, het verhoogde of
normale been mineraal digtheid (BMD). Die vraag of hiper insulin ernie 'n verlies aan beenmassa
teëwerk word dikwels gevra. Teenstrydigheid oor die rol van insulien as 'n osteo-anaboliese stof
bestaan egter steeds en hierdie vraag bly dus onbeantwoord. Dat insulien seintransduksie wel 'n
kritiese rol speel in beenvormende osteoblaste is onlangs bevestig in studies met muise waarvan
die geen vir IRS-l uitgeslaan is. Hierdie muise ontwikkel 'n lae omset osteopenie weens
verswakte proliferasie en differensiasie.
fn hierdie studie is gevind dat insulien wel in vitro as 'n osteoblast mitogeen kan funksioneer.
Dit is in drie relatief onvolwasse (MBA-15.4, -15.6 muis en MG-63 mens) sellyne geillistreer,
deur betekenisvolle verhogings in insulien-geaktiveerde proliferasie. In MBA-15.4 preosteoblaste
is die persentasie verhoging in insulien-gestimuleerde proliferasie vergelykbaar met
dié van die bekende mitogeniese forbolester, TPA. Die UMR-I06 sellyn het kenmerke van
gedifferensieerde osteoblaste, en was baie minder responsief op insulien behandeling. Die
verskil in die proliferasie vermoë van die verskillende sellyne kan die gevolg wees van verskille
wat bestaan tussen spontaan getransformeerde sellyne of die stadium van sel differensiasie.
'n MEK 1/2 inhibitor, UO126 en 'n PB-kinase inhibitor, wortmannin, is gebruik om die insulien
seintransduksie pad noodsaaklik vir die aktivering van ERK en osteoblast proliferasie te bepaal.
In MBA-1S.4 muis pre-osteoblaste, was fetale kalf SenlTI1(FKS)-geinduseerde DNA sintese
totaal afhanklik van MEK. Beide die MBA-15.4 en die meer volwasse MBA-15.6 muis
osteoblaste was weerstandig teen die inhibitors op hulle eie, of in kombinasie. Verhoogde
MEK-inhibitor konsentrasies het geen verdere effek gehad nie en in verskeie eksperimente is 'n
verhoging in preliferasie selfs waargeneem met MEK-inhibisie. Hierdie resultate dui aan dat die
klassieke insulien mitogeniese pad nie betrokke is in MBA-I5.4 gestimuleerde selproliferasie
nie. Wortmannin het geen effek gehad op insulien- of20% FKS-gestimuleerde DNA sintese nie,
maar het wel die aktivering van PB-kinase se metaboliese teiken, AktJPKB geinhibeer. Insulien
seintransduksie aktiveer dus ERK deur beide MEK en PB-kinase, maar het geen effek op
proliferasie gehad nie. FKS-gestimuleerde ERK aktivering en proliferasie was totaal afhanlik
van MEK-ERK aktivering. Insulien-geaktiveerde DNA sintese in die mens MG-63 osteoblaste was gedeeltelik afhanklik
van beide MEK en PB-kinase. Alhoewel IPA ook PB-kinase kon aktiveer, was dit totaal
afhanklik van MEK vir DNA sintese. Dit dui aan dat daar 'n PB-kinase stroom-op van 'n
dominante MEK-ERK seintransduksie pad voorkom. Die verskille wat ons dus waargeneem het
in insulien mitogeniese seintransduksie tussen muis en mens, kan aandui dat insuliengestimuleerde
seintranduksie paaie kan verskil van spesie tot spesie. Dit is bevestig met die
muisselle wat onafhanklik is en mens selle wat afhanklik is van MEK aktivering vir insuliengeaktiveerde
DNA sintese.
Kroniese, langtermyn steroied behandeling kan beenverlies veroorsaak en die effek van
glukokortikoide (GK) op die insulien mitogeniese pad in osteoblaste is dus ook ondersoek.
Natrium-ortovanadaat, 'n proteien tirosien fosfatase (PIP) inhibitor het GK-verlaagde
proliferasie in repons tot beide IPA- en FKS behandeling herstel in MBA-lSA en MG-63
preosteoblaste. PIPs soos SHP-l en PIP-l B funksioneer deur gefosforileerde kinases te
defosforileer en dus te inaktiveer. Beide SHP-l and PIP-lB kon assosieer met kinases in die
mitogeniese insulien seintransduksie pad van vinnig groeiende MBA-IS A preosteoblaste in
10% FKS. Verder het SHP-I ook geko-immunopresipiteer met aktiewe, tirosien-gefosforileerde
ERK, wat aandui dat SHP-I met ERK assosieer om dit te defosforileer en inaktiveer. Die MEKERK
of PB-kinase paaie is nie belangrik vir insulien-geaktiveerde seintransduksie in muis
osteoblaste nie. Dit is dus onwaarskynlik dat die PIPs 'n rol sal speel in die negatiewe
regulering van hierdie seintransduksie paaie. Die ontdekking dat vanadaat nie glukokortikoiedverlaagde
insulien-geaktiveerde DNA sintese kan herstel nie, toon dat vanadaat-sensitiewe PIPs
nie 'n rol speel in insulien-geaktiveerde proliferasie in muisselle nie. Hierdie bevinding het
verder bevestig dat 'n nuwe insulien mitogeniese pad in die MBA-ISA, maar nie die MG-63
selle moontlik bestaan.
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An investigation into the molecular aetiology of Parkinson's disease in South African patientsGlanzmann, Brigitte 03 1900 (has links)
Thesis (MScMedSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Parkinson's disease (PD) is a severely debilitating neurodegenerative disorder that results in
motor circuit dysregulation and ultimately, causes impairment of movement. This condition
is due to the selective degradation of the dopaminergic neurons in the substantia nigra pars
compacta in the midbrain, which subsequently results in the pathological symptoms namely
bradykinesia, resting tremor, postural instability and rigidity. It was initially hypothesized
that individuals who develop PD were exposed to an environmental trigger(s) that caused the
onset of the disease, but more recently, a significant genetic component, coupled to
environmental factors have been implicated in disease pathogenesis. Currently, there are
eight genes (Parkin, PINK1, LRRK2, SNCA, DJ-1, ATP13A2, EIF4G1 and VPS35) that have
been directly implicated in PD.
Worldwide, the prevalence of neurodegenerative disorders is increasing as populations are
living longer. In Europe, Canada and USA, it has been projected that the prevalence of PD
may increase by a factor of two between 2010 and 2050; approximately a 92% increase. In
Tanzania (the only study done in sub-Saharan Africa) an even larger increase of 184%
between 2005 and 2025 is predicted, due to the fact that the speed of populations ageing in
developing countries, will exceed that of developed countries. Research into the causes and
risk factors underlying neurodegenerative disorders such as PD is therefore urgently needed
for policy makers and governments in developing nations to take appropriate action to deal
with this impending health care problem.
The aim of the present study was to investigate the molecular aetiology of a group of South
African PD patients. A total of 262 patients from various ethnic backgrounds were recruited
for the study, and 35% had a positive family history of PD with the average age at onset
(AAO) being 54.3 years of age (SD = 12.5 years). Mutation screening of the known PD
genes (Parkin, PINK1, LRRK2, SNCA and DJ-1) was performed using high resolution melt
and Sanger sequencing. Genotyping was done using fluorescently-labelled PCR primers
followed by electrophoresis on an ABI 3130xl genetic analyser (for CTG repeats in JPH3)
and with a KASP™ Genotyping Assay (for a 16bp indel in DJ-1). In order to identify a
novel PD-causing gene, whole exome sequencing (WES) was conducted on three Afrikaner
probands with an Illumina Genome Hiseq 2000TM and the sequences were aligned using the NCBI Human Reference Genome 37.2. The BORG (Bio-Ontological Relationship Graph)
semantic database, which models the relationship of human and model organism genes to
functions, pathways and phenotypes, was used to filter and prioritise genetic variants shared
between the three PD exomes.
It was determined that the known PD genes do not play a significant role in disease
pathogenesis in the South African patients as only 15/262 (5.7%) of the patients harboured
mutations: seven in Parkin, one in PINK1, six in LRRK2 and one in SNCA. Only one of the
patients harboured a 16bp indel variant at the transcription start site of DJ-1. None of the
Black PD patients had pathogenic repeat expansions in JPH3 thereby excluding Huntington
disease-like 2 as a cause of the disease phenotype.
Genealogical analysis revealed that six of the apparently unrelated Afrikaner PD probands
were related to a founder couple that immigrated to South Africa in the 1600s which suggests
that there is a possible founder effect for the disease. Bioinformatics analysis of WES data
on three of the probands identified 21 variants in 12 genes that were present in all three PD
exomes and fulfilled various criteria. Sanger sequencing was used for verification of five
variants and of these, two (in CDC27 and NEDD4) were found to be artefacts. The
remaining three (in HECDT1, TBCC and RNF40) were excluded based on the lack of cosegregation
with disease and the high frequency of the allele in controls. Further work is
necessary to verify the presence of the remaining sixteen variants and to characterise each of
them for their possible pathogenicity.
The discovery of novel PD-causing genes is important as this may shed light on the pathways
or processes that are involved. A current hypothesis implicates the lysosome-dependent
pathway as a unifying biochemical pathway that can account for the phenotypic spectrum
within PD. Notably, although Mendelian forms are thought to account for only about 10-
15% of cases, the study of Mendelian inherited variants is likely to provide insight into the
pathophysiology of the more common sporadic form of this condition. Dissecting the key
molecular mechanisms underlying PD will provide critical information for improved
treatment strategies and drug interventions that will ultimately prevent or halt neuronal cell
loss in susceptible individuals. / AFRIKAANSE OPSOMMING: Parkinson se siekte (PS) is 'n erge neurodegeneratiewe bewegings-siekte, wat motorstroombaan
disregulasie veroorsaak. Dit lei uiteindelik tot beperkte bewegings vermoëns. Hierdie toestand
word veroorsaak weens die selektiewe agteruitgang van die dopaminergeniese neurone in die
substantia nigra pars compacta in die midbrein, wat later lei tot die patologiese simptome
naamlik: bradykinesia, rustende spiersametrekkings, posturale onstabiliteit en rigiditeit. Daar is
aanvanklik vermoed dat individue wat PS ontwikkel, aan 'n omgewingsfaktor(e) blootgestel is
wat die aanvang van die siekte veroorsaak het, terwyl meer onlangs is daar 'n aansienlike
genetiese komponent tesame met omgewingsfaktore geïdentifiseer, wat betrokke is by die
patogenese van die siekte. Tans is daar agt gene (Parkin, PINK1, LRRK2, SNCA, DJ-1,
ATP13A2, EIF4G1 en VPS35) wat direk by PS geïmpliseer is.
Wêreldwyd is daar ‗n toenemende voorkoms van neurodegeneratiewe siektes aangesien
bevolkings langer leef. In Europa, Kanada en die VSA, is daar geprojekteer dat die voorkoms
van PS tussen 2010 en 2050 met 'n faktor van twee verhoog kan word. Dit is ongeveer 'n 92%-
verhoging. In Tanzanië (die enigste studie wat tot dusver in sub-Sahara Afrika gedoen is) word
daar selfs ‗n groter toename, van 184% tussen 2005 en 2025 voorspel. Dit is te danke aan die feit
dat die bevolkings- veroudering in ontwikkelende lande die van ontwikkelde lande sal oorskry.
Ondersoeke na die oorsake en risiko-faktore onderliggend aan neurodegeneratiewe siektes,
byvoorbeeld PS, word dus dringend benodig deur beleidmakers en regerings in ontwikkelende
lande, sodat hulle die nodige stappe kan neem om hierdie dreigende gesondheidsorg-probleem op
te los.
Die doel van die huidige studie was om ondersoek in te stel na die molekulêre etiologie van 'n
groep Suid-Afrikaanse PS pasiënte. 'n Totaal van 262 pasiënte van verskillende etniese
agtergronde, is gewerf vir die studie. Hiervan het 35% 'n positiewe familiegeskiedenis van PS en
die gemiddelde aanvangs ouderdom (AAO) was 54,3 jaar (SD = 12,5 jaar). Mutasie-analise van
die bekende PS gene is uitgevoer met behulp van hoë resolusie smelt en Sanger
volgordebepaling. Genotipering is gedoen met behulp van fluoresserend geëtiketteerde PKR
inleiers met elektroforese, op 'n ABI 3130xl genetiese analiseerder (CTG herhalings in JPH3), en
met 'n KASP ™ Genotipering toets (vir 'n 16bp indel in DJ-1). Ten einde, om 'n nuwe PSveroorsakende
geen te identifiseer was heel eksoom volgordebepaling (WES) uitgevoer op drie
Afrikaner PS positiewe pasiënte met 'n Illumina Genome Hiseq 2000™ en die volgorders is gerangskik met behulp van die NCBI Menslike Verwysings Genoom 37.2. Die BORG (Bio-
Ontologiese Verhoudings Grafiek) semantiese databasis, wat gebaseer is op die verhouding van
die mens en model organisme gene funksies, paaie en fenotipes, en is gebruik om genetiese
variante, wat gedeel word tussen die drie PS exome te filtreer en te prioritiseer.
Daar is vasgestel dat die bekende PS gene nie 'n belangrike rol in die patogenese van die siekte
in die Suid-Afrikaanse pasiënte speel nie. Dit is aangesien slegs 15/262 (5.7%) van die pasiënte
bekende mutasies dra: sewe in Parkin, een in PINK1, ses in LRRK2 en een in SNCA. Slegs een
van die pasiënte het 'n 16bp delesie variant in die transkripsie promotor area van DJ-1 gedra.
Geen van die Swart PS pasiënte het patogeniese herhalings in JPH3 vertoon nie. Gevolglik is
Huntington siekte-agtige 2 uitgesluit as 'n oorsaak van die siekte fenotipe.
Genealogiese analise het getoon dat ses van die skynbaar onverwante Afrikaner PS pasiënte
verwant is aan 'n stigter paartjie wat in die 1600's na Suid-Afrika geïmigreer het, wat daarop dui
dat daar 'n moontlike stigter effek vir die siekte is. Bioinformatiese analise van WES data vir drie
van die pasiënte, het 21 variante in 12 gene geïdentifiseer, wat in al drie PS exome teenwoordig
was en verskeie kriteria vervul het. Sanger volgordebepaling is gebruik vir die bevestiging van
vyf variante en van hierdie, is twee (in CDC27 en NEDD4) bevind om artefakte te wees. Die
oorblywende drie (in HECDT1, TBCC en RNF40) is uitgesluit gebaseer op die gebrek aan
gesamentlike-segregasie met die siekte en die hoë frekwensie van die allele in die kontrole groep.
Verdere werk is nodig om die teenwoordigheid van die oorblywende variante te verifieer en om
elkeen van hulle te karakteriseer vir hulle moontlike patogenisiteit.
Die ontdekking van die nuwe PS-veroorsakende gene is belangrik aangesien dit lig kan werp op
die stelsels of prosesse wat betrokke is. 'n Huidige hipotese impliseer die lisosoom-afhanklike pad
as 'n verenigende biochemiese padweg, wat verantwoordelik is vir die fenotipiese spektrum binne
PS. Alhoewel Mendeliese vorms vermoedelik verantwoordelik is vir slegs omgeveer 10-15% van
die gevalle, is die studie van Mendelse gene geneig om insig te verkry in die patofisiologie van
die meer algemene sporadiese vorm van hierdie toestand. Ontleding van die kern molekulêre
meganismes onderliggend aan PS sal kritiese inligting vir beter strategieë vir behandeling en
geneesmiddel-intervensies voorsien, wat gevolglik neuronale sel verlies in vatbare individue sal
voorkom of beëindig. / Medical Research Council / National Research Foundation / Harry Crossley Foundation
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Laparoscopic surgery for rectovaginal endometriosis : a retrospective descriptive study from a single centreGooding, Matthew Simon 12 1900 (has links)
Thesis (MMed)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Background
Rectovaginal endometriosis accounts for 5-10% of cases of endometriosis and constitutes one of the forms of deep infiltrating endometriosis. . Deep infiltrating endometriosis involving the bowel is most frequently encountered in the rectovaginal septum and is considered to be the most severe form of the disease and the most difficult to treat surgically owing to its invasive nature. There are currently no studies on this topic pertaining to a South African context.
Study Objective
To document the outcomes in 112 patients undergoing laparoscopic surgery for rectovaginal endometriosis.
Methods
A retrospective audit of 112 women undergoing laparoscopic surgery for rectovaginal endometriosis at Vincent Pallotti's Aevitas Fertility Clinic was undertaken. Eligibility was established by identifying women from a surgical database based on medical aid coding as well as a review of individual case notes. Patients were telephonically contacted to gather any missing information and to assess further outcomes.
Design Classification
Study number S11/11/036. This study was approved by the Health Research Ethics Committee at Stellenbosch University and was conducted according to ethical guidelines and principles of The International Declaration of Helsinki, South African Guidelines for Good Clinical Practice and the Medical Research Council (MRC) Ethical Guidelines for Research.
Setting
Vincent Pallotti’s Aevitas Reproductive Medicine Clinic
Patients
112 consecutive patients suffering from rectovaginal endometriosis
Interventions: Laparoscopic surgery for treatment of deep infiltrating, namely rectovaginal endometriosis
Measurements and Main Results
Primary outcome: Complications of laparoscopic surgery for rectovaginal endometriosis included one patient requiring a blood transfusion (0,9%), three cases of rectovaginal fistula (2,7%), two bowel injuries (1,8%)-detected and managed intra-operatively , one ureteric injury (0,9%), one pelvic abscess (0,9%) and the need for three urgent re-operations (2,68%).
Secondary outcome: Of the 71 patients desiring fertility 39 (54,9%) fell pregnant of which 27 (69,2%) were spontaneous.
Conclusion
To our knowledge this is the first study assessing surgical outcomes in the management of deep infiltrating endometriosis from South Africa. These outcomes are in keeping with complication rates quoted in the international literature. Most of the surgery was performed using the shaving technique, in keeping with international trends, whilst fourteen cases required the performance of a segmental resection owing to extensive disease. In trained hands laparoscopic surgery is a valid management option in the management of rectovaginal endometriosis. / AFRIKAANSE OPSOMMING: Agtergrond
Vyf tot tien persent van alle endometriose gevalle kan toegeskryf word aan rektovaginale endometriose. Dit word beskou as een van die vorme van diep infiltrerende endometriose. Diep infiltrerende endometriose van die derm kom meestal in die rektovaginale septum voor en word as die ernstigste vorm van die siekte beskou. Dit is die moeilikste om chirurgies te behandel weens sy indringende aard. Daar is tans geen studies beskikbaar oor hierdie onderwerp in die Suid-Afrikaanse konteks nie.
Doel van die studie
Om die uitkomste te dokumenteer van 112 pasiënte wat laparoskopiese chirurgie vir rektovaginale endometriose ondergaan het.
Metodes
'n Retrospektiewe oudit is by Vincent Pallotti se Aevitas Fertiliteitskliniek gedoen van 112 vroue wat laparoskopiese chirurgie vir rektovaginale endometriose ondergaan het. Geskikte pasiënte is geïdentifiseer vanaf 'n chirurgiese databasis gebaseer op mediese kodering, sowel as vanaf 'n oorsig van pasiënt notas. Pasiënte is telefonies genader om ontbrekende inligting in te samel en verdere uitkomste te evalueer.
Klassifikasie Ontwerp
Studie nommer S11/11/036. Hierdie studie is deur die Gesondheids Navorsing Etiese Komitee van die Universiteit van Stellenbosch goedgekeur en uitgevoer volgens die etiese riglyne en beginsels van die Internasionale Verklaring van Helsinki, Suid-Afrikaanse Riglyne vir Goeie Kliniese Praktyk en die Mediese Navorsingsraad (MNR) se Etiese Riglyne vir Navorsing.
Instelling
Vincent Pallotti se Aevitas Reproduktiewe Medisyne Kliniek
Pasiënte
112 agtereenvolgende pasiënte met rektovaginale endometriose.
Ingrepe: Laparoskopiese chirurgie vir die behandeling van diep infiltrende, rektovaginale endometriose.
Resultate
Primêre uitkoms: Komplikasies van laparoskopiese chirurgie vir rektovaginale endometriose het ingesluit: een pasiënt wat 'n bloedoortapping benodig het (0,9%), drie gevalle van rektovaginale fistels (2,7%), twee dermbeserings (1,8%) - intraoperatief gediagnoseer en herstel, een ureter besering (0,9%), een bekkenabses (0,9%) en drie dringende herhaal operasies (2,68%).
Sekondêre uitkoms: Van die 71 pasiënte wat fertiliteit verlang het: 39 (54,9%) het swanger geraak, waarvan 27 (69,2%) spontaan was.
Gevolgtrekking
Sover ons kennis strek, is dit die eerste Suid-Afrikaanse studie waar daar na die chirurgiese uitkomste in die behandeling van diep infiltrerende endometriose gekyk is. Hierdie uitkomste stem ooreen met internasionale literatuur in terme van komplikasie syfers. Die meeste van die operasies is uitgevoer met behulp van die skeer-tegniek, in ooreenstemming met internasionale tendense, terwyl veertien gevalle segmentele reseksies vereis het weens uitgebreide siekte. In goed opgeleide hande is die laparoskopiese behandeling van rektovaginale endometriose ‘n geldige behandelings opsie.
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