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Opname van opinie van regslui ten opsigte van doeltreffendheid van geregtelike post mortems in die Wes-KaapPienaar, J. P. January 2001 (has links)
Study project (M.Med.) -- University of Stellenbosch, 2001. / ENGLISH ABSTRACT: The main purpose in doing forensic post mortems is to supply information to the
judicial system. Medical personnel involved in doing post mortems seldom get
feedback regarding efficiency. Numerous allegations have been made regarding
the work of district surgeons in terms of forensic post mortems, often suggesting
that the work is substandard.
In South Africa district surgeons do post mortems mostly in the rural areas, and
training centre personnel do forensic post mortems in urban areas. Training
centre personnel include specialized forensic pathologists, registrars and medical
officers working in the Departments of Forensic Medicine, affiliated to
universities. The South African Police Service mostly manages government
mortuaries. The South African forensic medico-legal system is unique, and does
not correspond in with the four main systems used worldwide.
Research was done by sending 200 questionnaires to a representative group
from the legal fraternity of the Western Cape (including judges / magistrates,
state prosecutors, private lawyers) and also the South African Police Service
investigating officers. The judiciary, as the users of the information generated
through forensic post mortems, are therefore in a suitable position to determine
the efficacy of forensic post mortem. The questionnaire was structured to
determine the general perception, as well as comments, regarding 9 different
aspects involved with doing forensic post mortems. These include the
thoroughness and completeness of reports, standard of academic knowledge,
efficacy of verbal testimony in court, length of time in releasing the report, general
attitude, efficacy of sketches and diagrams, efficacy of photography, sufficient
taking of toxicology samples and sufficient utilization of special laboratory
investigations. The last question was an open question to allow for general
comments and anecdotes.
For each aspect it was also determined whether there was a difference in efficacy
noted between the two groups. The effect of this, if any, on the judicial criminal
justice system was also assessed.
A different questionnaire was sent out to all forensic pathologists in the Western
Cape. The standard of work of the district surgeons was hereby assessed.
General comment regarding academic knowledge, and findings at post mortem
made by district surgeons was assessed. The pathologists were also questioned
regarding the general attitude of district surgeons, and imput were asked
regarding continued medical education programs. An area for general comment
was also supplied.
The main findings were as follows:
a. The legal fraternity in the Western Cape is generally satisfied with the
efficiency of forensic post mortems, except the use of laboratory
investigations and also the length of time to release reports.
b. The legal fraternity could determine a difference in the efficiency of post
mortems done by district surgeons and training centre personnel.
Training centre personnel were generally regarded as more effective.
c. The difference between the two groups, due to ineffective district surgeon
post mortems, had a negative effect on the criminal justice system.
The following recommendations were made:
a. Training centre personnel: Serious consideration should be given to
appointing qualified forensic pathologists in the rural areas. Training
centre personnel should also be more involved in training the district
surgeons.
b. District surgeons: The training, re-training and continued medical
education of district surgeons in the Western Cape should be prioritized.
The service conditions should also be reviewed.
c. Administrative: Audit of post mortem reports. The efficiency regarding
court appearances should be audited through the Department of Justice.
Administrative power will be necessary to oversee the above-mentioned
recommendations. / AFRIKAANSE OPSOMMING: Die hoofdoel met die doen van geregtelike post mortems is om inligting te
verskaf aan die regsproses. Medici gemoeid met geregtelike post mortems kry
baie seide terugvoer oor die effektiwiteit van werk gelewer in die hof. Daar is ook
herhaaldelik suggesties gemaak dat die werk van die distriksgeneeshere met
betrekking tot geregtelike post mortems soms suboptimaal is.
Regsmediese post mortemdienste in Suid Afrika word verskaf deur distriksgeneeshere
in die platteland, en deur personeel verbonde aan opleidingshospitale
in die stede. Die opleidingssentra-personeel sluit in gespesialiseerde
forensiese patoloe, kliniese assistente en mediese beamptes werksaam in 'n
Departement van Geregtelike Geneeskunde verbonde aan 'n universiteit. Staats-
Iykshuise word bestuur en beheer deur die Suid-Afrikaanse Polisiediens. Daar
bestaan geen soortgelyke model vir die voorsiening van regsmediese dienste in
die res van die wereld nie.
Navorsing is gedoen deur vraelyste uit te stuur aan 200 verteenwoordigende
regslui (wat insluit regters/landdroste, staatsaanklaers, privaat regslui) en aan
Suid-Afrikaanse Polisiediens-ondersoekbeamptes in die Wes Kaap. Die reg, as
verbruikers van regsmediese dienste is gekies om 'n opinie uit te spreek oor die
doeltreffendheid van forensiese post mortems. Die vraelyste is gestruktureer
om die algemene tevredenheid en opinies en kommentaar te bekom oor nege
verskillende aangeleenthede rakend die forensiese post mortem, nl. deeglikheid
en volledigheid van verslae, standaard van akademiese kennis, effektiwiteit van
verbale getuienisaflegging in die hof, tydsverloop vir lewering van verslae,
houding en gesindheid van medici, doeltreffendheid van sketse en diagram me,
effektiewe gebruik van fotografie, effektiewe gebruik van toksikologiese
ondersoeke, effektiewe gebruik van spesiale ondersoeke, asook 'n algemene oop
vraag vir kommentaar oor probleemareas.
Daar word vervolgens vir elke aangeleentheid bepaal of daar 'n verskil in
effektiwiteit opgelet word tussen twee mediese subgroepe, en indien wei watter
groep meer effektief funksioneer. Verder sal nagegaan word of die regsproses
geaffekteer word deur enige van bogenoemde bevindinge.
'n Verskillende vraelys is uitgestuur aan aile geregtelike patoloe in die Wes-Kaap.
Hiermee word die standaard van die werk van distriksgeneeshere beoordeel.
Kommentaar is gevra oor akademiese kennis met betrekking tot geregtelike post
mortems en oor bevindinge gemaak deur distriksgeneeshere by post mortems.
Daar word ook gevra oor die algemene houding van distriksgeneeshere, asook
vir voorstelle vir voortgesette onderrigsprogramme. 'n Oop vraag is gestel vir
kommentaar oor probleemareas.
Uit die response is die volgende gevolgtrekkings gemaak:
a. Die regslui in die Wes-Kaap is oor die algemeen tevrede met die diens
gelewer met betrekking tot geregtelike post mortems, met uitsondering
van die effektiwiteit van laboratoriumondersoeke, en ook oor die tydsverloop
tussen die doen van post mortem en die vrystel van die verslae.
b. Die regslui kon 'n verskil bepaal in die graad van effektiwiteit van post
mortems gedoen deur distriksgeneeshere en opleidingssentra-personeel.
Opleidingssentra-personeel is deur die meerderheid van respondente
identifiseer as meer effektief.
c. Die verskil tussen die twee groepe, a.g.v. oneffektiewe distriksgeneesheer
post mortems, het 'n negatiewe effek op die regsproses.
Aanbevelings is gemaak om die sisteem te verbeter:
a. Opleidingssentra-personeel: Die uitplasing van gekwalifiseerde forensiese
patoloe in die platteland moet oorweeg word. Opleidingssentrapersoneel
kan ook meer betrokke wees by opleiding van distriksgeneeshere.
b. Distriksgeneeshere: Aandag moet gegee word aan die opleiding,
heropleiding en voortgesette geneeskundige onderrig van distriksgeneeshere
in die Wes-Kaap. Die werksomstandighede waaronder hulle
diens lewer moet ook aangespreek word.
C. Administratief: Ouditering van post mortem verslae. Ouditering van
effektiwiteit van hofverskynings, in assosiasie met die Departement van
Justisie. Admininistratiewe wilskrag sal ook essensieel wees by
implementering van bogenoemde voorstelle.
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Longitudinal investigation of vaccine specific antibody levels and cellular markers of adaptive immune responses in HIV Exposed Uninfected (HEU) and Unexposed (UE) infantsNaidoo, Shalena 03 1900 (has links)
Thesis (MScMedSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Background: In South Africa alone, 30% of women of child-bearing age are infected with HIV. With the increasing focus and success of prevention of mother-to-child transmission (PMTCT) programmes, an estimated 300 000 infants are born exposed to HIV every year. The underlying impact of in utero HIV exposure on infant immune health has not been extensively characterised. Clinical follow-up of these HIV-exposed uninfected (HEU) infants reveals increased infectious morbidity and mortality compared to their unexposed (UE) counterparts. Objectives: (i) To evaluate and characterise adaptive immune properties by measuring vaccine-specific antibody levels in children from 2 weeks to 2 years of age in the presence and absence of maternal HIV infection. (ii) To investigate specific cellular markers of immune activation, immune regulation, apoptosis and B cell memory on T and B cell populations in HEU and UE children measured at 18 and 24 months of age. Methods: This sub-investigation formed part of a collaborative pilot study between the universities of British Columbia (Vancouver, Canada) and Stellenbosch. A total of 95 HIV-positive and HIV-negative mothers were recruited after delivery at Tygerberg Hospital, and signed informed consent for their infants to be included in the study. Of these infants, only 27 HEU and 30 UE infants were eventually enrolled and followed up at various time points, starting at two weeks of age. Four of these infants were confirmed to be HIV-positive at 2 weeks and clinically followed up according to the protocol, but were excluded from statistical data analyses. Blood was collected at 2, 6 and 12 weeks and again at 6, 12, 18 and 24 months of age. Quantitative IgG-specific antibodies to Haemophilus influenzae B (Hib), Bordetella pertussis, tetanus and pneumococcus were measured at each time point, using commercially available ELISA (Enzyme-Linked ImmunoSorbent) kits. Cellular markers of immune activation, immune regulation, apoptosis and memory were measured in various populations of T and B cells at 18 and 24 months only, by using four-colour flow cytometry and validated whole-blood staining methods. In addition, a functional assay was developed to evaluate cell susceptibility to apoptosis (spontaneously) by measuring the expression of Annexin V on both CD4+ T and CD20+ B cells after 16 and 24-hour incubation periods. The statistical analysis of the antibody data was conducted by repeated-measures ANOVA (i.e. analysis of variance), using a mixed-model approach. Differences in the expression of the two groups’ cellular markers were compared by employing one-way ANOVA. An F test p value (which assumes normality) was reported, while the non-parametric Mann-Whitney U test served as confirmatory tool. Repeated-measures ANOVA was used for the evaluation of the functional spontaneous apoptosis assay at three time points (ex vivo, 16 and 24 hours) on the 18-month samples, while one-way ANOVA was used for the 24-month samples. Results: The HEU group (n = 23) displayed significantly lower levels of antibodies to pertussis (20.80 vs 28.01 Food and Drug Administration [FDA] U/ml; p = 0.0237), tetanus (0.08 vs 0.53 IU/ml; p < 0.001) and pneumococcus (31.67 vs 80.77 mg/l; p = 0.003) than the UE group (n = 23) at 2 weeks of age. No statistical differences were noted for Hib antibody levels between the two groups at this time point. At 6 weeks of age, HEU infants displayed lower mean levels of all antibodies measured; however, these differences did not reach statistical significance.
Following vaccination, compared to UE controls, the HEU group presented with statistically significantly higher antibody levels to pertussis at 6 months (155.49 vs 63.729 FDA U/ml; p = 0.0013), 12 months (26.54 vs 8.50 FDA U/ml; p < 0.001) and 18 months of age (1658.94 vs 793.03 FDA U/ml; p = 0.0362). A significant difference in tetanus antibody levels between the two groups was only evident at 24 months, with the HEU group displaying higher levels (3.28 vs 1.70 IU/ml; p = 0.018) than the UE group. No differences were observed between the two groups following vaccination for Hib. At 18 and 24 months, the HEU group showed increased expression of cellular markers of immune activation (CD69 and CD40L) on CD4+ T cells compared to UE controls. The two groups showed similar expression of the cellular marker of activation CD38 on CD8+ T cells. The HEU group displayed significantly higher levels of CD127, the interleukin (IL) 7 receptor, on CD4+ T cells compared to UE controls at 18 months of age. The HEU group also showed increased expression of cellular markers of apoptosis on both CD4+ T and CD8+ T cells. No statistical significance was noted for the expression of Fas on CD4+ T cells at 18 and 24 months of age. However, at 24 months, the HEU group showed significantly increased expression of FasL on both CD4+ T and CD8+ T cells. During cell culture experiments, the HEU group displayed increased susceptibility to spontaneous apoptosis shown by increased Annexin V expression on CD4+ T cells after a 16-hour incubation period at both 18 and 24 months. At 18 and 24 months, no difference was noted in the two groups’ immune regulation as measured by the expression of CTLA-4. The HEU group displayed increased levels of the cellular markers of immune activation CD80 on CD20+ B cells at 18 and 24 months of age. The HEU group also showed significantly increased levels of CD69 on CD19+ B cells at 24 months. No statistical significance was reached for the expression of CD62L and CD10 at either 18 or 24 months. Although the HEU group displayed increased levels of apoptosis (Fas) on CD20+ B cells, no statistical significance was reached at 18 or 24 months of age. In addition, the HEU group showed no difference in the expression of programmed death 1 (PD-1) at 18 and 24 months. HEU and UE groups showed similar expression of Annexin V after 16 hours of incubation in the 18 and 24-month samples. The expression of the biomarker of B cell memory CD27 on CD20+ B and CD19+ B cells was comparable between the two groups at both time points. Conclusion: At 2 and 6 weeks, lower mean antibody responses in HEU infants suggest poor placental transfer due to maternal HIV infection, while increased responses to specific antibodies may reflect an exaggerated immune response to immunisation. These robust responses may be due to the lack of competition with maternal antibodies, or may be ascribed to indirect stimulation of B cells via the activation of T cells. A hyper-inflammatory state is an imminent danger, with increased expression of cellular markers of immune activation and apoptosis that may be consistent with early HIV exposure that persists following infancy. These observations may serve as contributing factors to the extensively documented increased susceptibility to infections in the HEU population. Although these findings are consistent with a primed immune system, larger studies are required to confirm these observations in relation to clinical outcomes and to assess further whether these differences persist in later years. / AFRIKAANSE OPSMOMMING: Agtergrond: In Suid-Afrika alleen het 30% van vroue van ʼn vrugbare leeftyd MIV. Met die toenemende fokus en sukses van programme vir die voorkoming van moeder-na-kind-oordrag (sogenaamde PMTCT-programme) word ongeveer 300 000 babas jaarliks aan MIV blootgestel. Die onderliggende impak van intra-uteriene MIV-blootstelling op ʼn baba se immuunstelsel is nog nie omvattend beskryf nie. Kliniese opvolgondersoeke van hierdie MIV-blootgestelde dog onbesmette babas (sogenaamde HEU’s) dui op ʼn hoër siekte- en sterftesyfer weens infeksies as hul nieblootgestelde eweknieë (sogenaamde UE’s). Doelstellings: (i) Om kinders met MIV-positiewe en MIV-negatiewe moeders se aangepaste (verworwe) immuuneienskappe te beoordeel en te beskryf deur hulle vaksienspesifieke teenliggaamvlakke vanaf die ouderdom van twee weke tot twee jaar te meet. (ii) Om ondersoek in te stel na bepaalde sellulêre merkers van immuunaktivering, immuunregulering, apoptose en B-selgeheue by die T- en B-selgroepe van sowel HEU’s as UE’s op die ouderdom van 18 en 24 maande. Metodes: Hierdie subondersoek het deel uitgemaak van ʼn samewerkende loodsondersoek tussen die universiteite van Brits-Columbië (Vancouver, Kanada) en Stellenbosch. Altesaam 95 MIV-positiewe en MIV-negatiewe moeders is gewerf nadat hulle by Tygerberghospitaal geboorte geskenk het, en het ingeligte toestemming verleen dat hul babas by die studie ingesluit kon word. Van dié babas is slegs 27 HEU’s en 30 UE’s uiteindelik in die studie opgeneem en in verskillende stadia vanaf die ouderdom van twee weke opgevolg. Vier van die babas is op twee weke as MIV-positief bevestig en volgens die protokol klinies opgevolg, maar is van die statistiese dataontleding uitgesluit. Bloedmonsters is op twee, ses en 12 weke en weer op ses, 12, 18 en 24 maande geneem. Kwantitatiewe IgG-spesifieke teenliggame teen Haemophilus influenzae B (Hib), Bordetella pertussis, tetanus en pneumokokkus is telkens met behulp van kommersieel verkrygbare ELISA- (“Enzyme-Linked ImmunoSorbent”-)stelle bepaal. Sellulêre merkers van immuunaktivering, immuunregulering, apoptose en geheue is op slegs 18 en 24 maande by verskillende populasies T- en B-selle deur middel van ʼn vierkleurvloeisitometrie en geldig verklaarde volbloedkleuringsmetodes bepaal. Voorts is ʼn funksionele toets ontwikkel om selvatbaarheid vir apoptose te bepaal deur die ekspressie van Annexin V op sowel CD4+ T- as CD20+ B-selle ná 16 en 24 uur van inkubasie te meet. Die statistiese ontleding van die teenliggaamdata is met behulp van herhaaldemetings-ANOVA (d.w.s. afwykingsontleding) volgens ʼn gemengdemodel-benadering gedoen. Verskille in die twee groepe se sellulêre merkervlakke is deur middel van eenrigting-ANOVA vergelyk. ʼn F-toets-p-waarde (wat normaliteit veronderstel) is bereken, terwyl die nieparametriese Mann-Whitney-U-toets as bevestigende instrument gedien het. Vir die 18 maande-monsters is herhaaldemetings-ANOVA gebruik om die funksionele toets vir spontane apoptose in drie stadia (ex vivo, op 16 uur en op 24 uur) te beoordeel. Vir die 24 maande-monsters is eenrigting-ANOVA gebruik. Resultate: Op die ouderdom van twee weke het die groep HEU’s (n = 23) aansienlik laer teenliggaamvlakke teen kinkhoes (20.80 vs 28.01 Food and Drug Administration [FDA] U/ml; p = 0.0237), tetanus (0.08 vs 0.53 U/ml; p < 0.001) en pneumokokkus (31.67 vs 80.77 mg/l, p = 0.003) as die UE-groep (n = 23) getoon. In dié stadium is geen statistiese verskille in Hib-teenliggaamvlakke tussen die twee groepe opgemerk nie. Op ses weke het die groep HEU’s laer gemiddelde vlakke van ál die betrokke teenliggame getoon, hoewel hierdie verskille nie statisties beduidend was nie.
In vergelyking met die UE-kontrolegroep het die groep HEU’s ná inenting statisties beduidend hoër teenliggaamvlakke teen kinkhoes getoon op ses maande (155.49 vs 63.729 FDA U/ml; p = 0.0013), 12 maande (26.54 vs 8.50 FDA U/ml; p < 0.001) én 18 maande (1658.94 vs 793.03 FDA U/ml; p = 0.0362). ʼn Beduidende verskil in die twee groepe se tetanus-teenliggaamvlakke het eers op 24 maande geblyk, met die groep HEU’s s’n hoër (3.28 vs 1.70 IE/ml; p = 0.018) as die UE’s s’n. Ná inenting teen Hib is geen verskille tussen die twee groepe waargeneem nie. Op 18 en 24 maande het die HEU’s verhoogde ekspressie van sellulêre merkers van immuunaktivering (CD69 en CD40L) op CD4+ T-selle getoon in vergelyking met die UE-kontrolegroep. Soortgelyke vlakke van die sellulêre merker van aktivering CD38 is ook op die CD8+ T-selle van die twee groepe opgemerk. Op 18 maande het die HEU-groep ʼn beduidend verhoogde ekspressie van CD127, die IL-7-reseptor, op CD4+ T-selle getoon in vergelyking met die UE-kontrolegroep. Die HEU groep het ook verhoogde ekspressie van sellulêre merkers van apoptose op sowel CD4+ T- as CD8+ T-selle getoon. FAS-ekspressie op CD4+ T-selle op 18 en 24 maande was nie statisties beduidend nie, hoewel die HEU-groep op 24 maande beduidend verhoogde ekspressie van FasL op CD4+ T- sowel as CD8+ T-selle getoon het. In selkwekingseksperimente het die HEU-groep ʼn verhoogde vatbaarheid vir apoptose getoon na aanleiding van die ekspressie van Annexin V op CD4+ T-selle ná 16 uur van inkubasie op sowel 18 as 24 maande. Op 18 en 24 maande was immuunregulering, aan die hand van die ekspressie van CTLA-4, bykans dieselfde by albei groepe. Op sowel 18 as 24 maande toon die HEU’s verhoogde ekspressie van die sellulêre merker van immuunaktivering CD80 op CD20+ B-selle. Op 24 maande het die HEU’s ook aansienlik hoër vlakke van CD69 by CD19+ B selle getoon. Op nóg 18 nóg 24 maande was die ekspressie van CD62L en CD10 statisties beduidend. Hoewel verhoogde vlakke van apoptose (Fas) by CD20+ B-selle by die HEU-groep opgemerk is, was dit nie statisties beduidend op 18 óf 24 maande nie. Daarbenewens was daar ook geen verskil in die ekspressie van geprogrammeerde seldood 1 (PD-1) op 18 en 24 maande nie. Op 18 en 24 maande het die HEU’s en UE’s ʼn soortgelyke ekspressie van Annexin V ná 16 uur van inkubasie getoon. Op sowel 18 as 24 maande was die twee groepe se ekspressie van die biomerker van B-selgeheue CD27 op CD20+ B- en CD19+ B-selle vergelykbaar. Gevolgtrekking: Op twee en ses weke dui laer gemiddelde teenliggaamreaksies by HEU’s op swak plasentale oordrag weens die moeder se MIV-infeksie, terwyl verhoogde reaksies op bepaalde teenliggame weer op oordrewe immuunreaksie op inenting dui. Hierdie robuuste reaksie kan toegeskryf word aan die gebrek aan mededinging met die moeder se teenliggame, of kan deur indirekte stimulasie van die B-selle via die aktivering van die T-selle veroorsaak word. ʼn Hiperinflammatoriese toestand is ʼn dreigende gevaar, met verhoogde ekspressie van sellulêre merkers van immuunaktivering en apoptose wat met vroeë MIV-blootstelling met ʼn latere nawerking verbind kan word. Hierdie waarnemings kan bydraende faktore wees tot HEU’s se goed gedokumenteerde verhoogde vatbaarheid vir infeksies. Hoewel hierdie bevindings met ʼn geaktiveerde immuunstelsel strook, moet groter studies dit aan die hand van kliniese uitkomste bevestig en ook bepaal of hierdie verskille in later jare voortduur. / The Harry Crossley Foundation, Poliomyelitis Research Foundation (PRF) / NHLS Research Grant Trust
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The contribution of the placenta to the diagnosis of congenital tuberculosisRabie, Ursula 04 1900 (has links)
Thesis (MMed)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The aim of this pilot project was to determine whether mothers with laboratory confirmed or clinically
suspected tuberculosis (TB)
had evidence of TB in the placenta. A secondary objective was to correlate
evidence of placental TB with neonatal outcome. A total of 56 placentas were examined to determine if there were any specific histopathological features predictive of tuberculosis together with Ziehl-Neelsen (ZN) staining. A total of 30 cases were positive for maternal TB and one case was a false positive maternal diagnosis of TB, whilst 25 cases were negative for maternal TB. Biopsies from these 56 placentas were collected for conventional PCR from the paraffin embedded tissue blocks. The performance of these two diagnostic modalities (histopathology and PCR) was assessed coll ectively and individually, and compared to the neonatal outcome (presence or absence of active clinical mycobacterial tuberculosis infection) and evidence of maternal pulmonary and extra pulmonary tuberculosis.
The recognition of specific sites of lesions in the placenta (e.g. membranes vs. intervillous space) may lead to an understanding of the pathogenic mechanisms involved in matern
alfetal transmission of tuberculosis, and thereby pave the way for further studies in understanding the pathogenesis of congenital TB.
Invaluable knowledge was obtained in the diagnoses of M.tuberculosis in the placenta as it was found that micro abscesses and intervillositis were strong indicators of TB
infection in the placenta, however, ZN
staining still remains the gold standard for diagnosing M.tuberculosis infection in the placenta. PCR is found to have limitations, because only M.tuberculosis DNA is amplified
and does not distinguish live from dead bacteria.
The conclusion reached is that PCR is of limited value in the diagnosis of active M.tuberculosis
infection in the placenta using FFPE tissue, while certain histological changes may be indicative of such infection; however confirmation of the organism by ZN staining is still essential. / AFRIKAANSE OPSOMMING: Die hoofdoelwit van hierdie projek was om vas te stel of moeders met bevestigde of vermoedelike TB enige indikasie van TB in die plasenta toon. ‘n Tweede doelwit was om die neonatale uitkoms teenoor die plasentale TB te korreleer. ‘n Totale getal van 56 plasentas is ondersoek om vas te stel of daar enige spesifieke histopatologiese indikasies is van tuberkulose met die hulp van die ZN spesiale kleuring. Die totale getal positiewe vir TB was 30 asook ‘n vals positiewe geval vir TB en daar was 25 TB negatiewe gevalle. Ses en vyftig biopsies is versamel van paraffien in gebedteerde weefsel vir die gebruik in PKR. Die uitvoering van hierdie twee diagnostiese modaliteite is elk individueel ondersoek asook gesamentlik om dit te vergelyk met die neonatale uitkoms (m.a.w die teenwoordigheid of aanwesigheid van mikobakteriale tuberkulose infeksie) asook die teenwoordigheid van moederlike pulmunere en ekstra-pulmunere tuberkulose. Die spesifieke ligging van die letsels in die plasenta (bv. membrane vs. intervillus spasie) kan lei tot
verbeterde begrip van die patogeniese meganismes betrokke in die moeder fetale oordrag van tuberkulose en dit kan lei tot toekomstige navorsing. Waardevolle kennis is opgedoen in die diagnose van M.tuberkulose in die plasenta, want die letsels van mikro abbesses en intervillisitus gee ‘n goeie aanduiding van TB infeksie in die plasenta.
Die ZN kleuring bly nog steeds die standaard metode om M.tuberculose in die plasenta te diagnoseer.
PKR het baie limiete want dit kan slegs die
M.tuberkulose
DNA vermeningvuldig, maar dit kan nie
onderskeid tref tussen lewendige en dooie bakterie nie. The slotsom in hierdie projek is dat PKR ‘n
be
pperkte waarde het in die diagnose van aktiewe
M
.tuberkulose
in die plasenta, deur die gebruik van
formalien gefikseerde paraffien ingebedteerde weefsel nie terwyl sekere histologiese veranderinge ‘n
aa
nduiding van sodanige infeksie kan wees maar dat dit deur die spesiale kleruring (ZN) bevestig moet
word. / National Health Laboratory Service (NHLS)
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Platelet flow cytometry and coagulation tests as markers of immune activation in chronic HIV infectionNkambule, Bongani Brian 03 1900 (has links)
Thesis (MScMedSc)--Stellenbosch University, 2012. / Bibliography / ENGLISH ABSTRACT: Background: In the era of antiretroviral therapy (ART), the risk of acquired immune deficiency
syndrome (AIDS) related deaths has decreased and people living with Human
Immunodeficiency Virus (HIV) now have prolonged life spans. However, an increasing trend of
non-AIDS associated deaths has been reported despite adequate control of viral loads. HIV
infection is established as a chronic inflammatory condition which is associated with an
increased risk for thrombosis. Thus HIV infected patients are at a higher risk of developing
cardiovascular disease (CVD) and other inflammatory-associated complications.
Inflammation is linked with thrombosis and promotes the formation of thrombin, which plays an
important role in platelet activation. Furthermore, activated platelets have been shown to play a
key role during infection and the inflammatory process, particularly by mediating interactions
between cells of innate immunity. Soluble markers of platelet activation have been shown to be
increased in HIV-infection. However, these have not been well documented by flow cytometry.
P-selectin CD62P is stored in the alpha granules of platelets and is expressed on the surface
only upon platelet activation. This facilitates interaction with other blood cells and the
endothelium. Activated platelets may play a role in HIV-induced atherosclerosis through the
expression and release of mediators that induce endothelial activation and support the adhesion
of leukocytes to the inflamed vessel wall. Fibrinogen is a precursor of the blood coagulatory
protein fibrin and the degradation of fibrin to D-dimer is a measure of the formation and the
subsequent dissolution of blood clots. In HIV infected patients, chronic inflammation induces the
up-regulated expression of tissue factor (TF) on monocytes which triggers the activation of the
clotting cascade and increases the level of D-dimers.
Methods: This pilot study consisted of ART naïve patients and all platelet flow analyses were
carried out on whole blood. In this study, a total of 57 adult South Africans were recruited from a
clinic in the Western Cape. These included 32 HIV positive patients and 25 HIV negative
individuals. The levels of platelet activation and platelet function were investigated using a novel
platelet cytometry assay. The method was optimized to ensure minimal platelet activation: no
centrifugation or red blood cell (RBC) lysis steps were performed. The platelet-specific markers
CD41a and CD42b were used to ensure gating on platelets only. CD62P expression was used
to evaluate platelet activation and these levels were correlated with Fibrinogen, hsCRP, Ddimer,
CD4 counts and viral load. Furthermore, platelet function was evaluated by investigating
the response of platelets to endogenous agonists which included adenosine diphosphate(ADP)
and arachidonic acid (AA) at varying concentrations. Results:This study demonstrated higher baseline levels of CD62P expression in treatment
naïve HIV positive patients as compared to uninfected controls (mean %CD62P 71.74 ± 2.18 vs
control 54.52 ± 2.42; p=<0.0001). In addition it was shown that %CD62P expression correlated
directly with platelet counts (r=0.374, p=0.042). Platelet counts showed an inverse correlation
with viral loads (give values) Fibrinogen levels correlated with the absolute WCC (r=0.659,
p=0.0021); absolute neutrophil count (r=0.619, p=0.0105); absolute monocyte count (0.562,
p=0.0235) and hsCRP (r=0.688 p=0.0011). In addition, fibrinogen showed a strong negative
correlation with CD4 counts (r=-0.594, p=0.0014) and therefore, may be a valuable marker of
both disease progression and risk of thrombosis in treatment naïve HIV positive patients.
HsCRP levels correlated with the absolute neutrophil counts (r=0.392, p=0.0005). The HIV
Group showed an overall hyper-response to ADP at a concentration 0.025 μM as compared to
uninfected controls (62.34 ± 9.7 vs control 36.90 ± 5.7, p=0.0433). Conclusions: In this study we describe a novel Flow Cytometry technique that may be used to
evaluate the levels of platelet activation and platelet function in HIV infected patients. In addition
we report a cost-effective panel in the form of fibrinogen, WCC and platelets that may be
valuable in predicting the progression of HIV infection to AIDS or other inflammatory- associated
complications in treatment naïve HIV infected patients. Platelet counts showed an inverse
correlation with viral loads and a direct correlation with the level of activated platelets. These
findings taken together suggest the potential prognostic value of platelet activation and platelet
counts in the context of asymptomatic HIV infected patients. Our findings suggest WCC and
Fibrinogen may be used to evaluate the inflammatory profile of individual HIV infected patients.
This may have a direct impact on HIV patient management prior to initiation of antiretroviral
therapy and valuable in monitoring responses to treatment. Further, we present a novel flow
cytometry based platelet functional assay and suggest the use of ADP at a concentration of
0.025 μM to evaluate platelet function optimally in HIV infected patients. The utilization of the
novel Flow Cytometry technique as described in this study would add significant value in the
assessment of thrombotic risk and disease progression in HIV infected patients and may
additionally prove to be of value in other chronic inflammatory conditions. / AFRIKAANSE OPSOMMING: Voorkennis: In die era van antiretrovirale terapie (ART), het die risiko van vigs-verwante
sterftes verminder en mense wat nou met volle naam (MIV) leef, het ‘n verlengde lewensduur.
Nogtans, word 'n toenemende neiging van nie-vigs geassosieer sterftes berig wat hoofsaaklik
toegeskryf word aan trombotiese toestande. MIV-infeksie word as 'n chroniese inflammatoriese
toestand beskou met ʼn verhoogde trombose risiko geassosieer word. Dus, MIV-besmette
pasiënte het 'n hoër risiko om kardiovaskulêre siekte (CVD) te ontwikkel ongeag of hulle ARV
naïef is of op behandeling is nie.
Inflammasie word geassosieer met trombose en bevorder die vorming van trombien, wat 'n
belangrike rol in plaatjie aktivering speel. Verder, word daar bewys dat geaktiveerde
bloedplaatjies 'n belangrike rol speel tydens infeksie en die inflammatoriese proses.Hulle
bemiddel interaksies tussen die selle van ingebore immuniteit. Daar word bewys dat oplosbare
merkers van plaatjie aktivering verhoog is in MIV-infeksie, maar die bewyse is nie so goed
gedokumenteer deur vloeisitometrie nie. P-selectin (CD62P) word gestoor in die alfa korrels van
plaatjies en word uitgedruk op die oppervlak slegs wanneer plaatjies geaktivering word;
daardeur fasilitering dit die interaksie met ander bloedselle en die endoteel. Geaktiveerde
plaatjies kan ook 'n rol in MIV-geïnduseerde aterosklerose speel deur middel van die uitdrukking
en vrylating van bemiddelaars wat endoteel aktivering induseer asook die adhesie van
leukosiete aan die ontsteekte vat wand ondersteun.. Fibrinogeen, 'n voorloper van die bloed
koagulatories proteïen fibrin en die degradasie van fibrin na D-dimeer is' n maatstaf van die
vorming en die daaropvolgende ontbinding van bloedklonte. Kroniese inflammasie in MIVbesmette
pasiënte, induseer die op-gereguleerde uitdrukking van weefsel faktor (TF) op
monosiete wat die aktivering van die stolling kaskade inisieer en die D-dimere vlakke verhoog.
Metodes: Hierdie loodsstudie bestaan uit ART naïewe pasiënte en al die plaatjie vloei ontleding
was op vol bloed uitgevoer. In hierdie studie, 'n totaal van 57 volwasse Suid-Afrikaners was van'
n kliniek in die Wes-Kaap gewerf. Dit sluit 32 MIV-positiewe pasiënte en 25 MIV negatiewe individue in. Die vlakke van plaatjie aktivering en plaatjie funksie was ge ondersoek deur middel
van 'n nuwe plaatjie sitometrie toets. Die metode was geoptimaliseer om minimale plaatjie
aktivering te verseker: dus geen sentrifugering of volle naam (RBS) liseer stappe was gebruik
nie. Die plaatjie-spesifieke merkers, CD41a en CD42b was gebruik om te verseker dat slegs
bloedplaatjes gekies word. Die uitdrukking van CD62P was gebruik vir die evaluering van
plaatjie aktivering en hierdie vlakke was gekorreleer met fibrinogeen, hsCRP, D-dimeer, CD4-
tellings en virale lading. Verder, was plaatjie funksie geëvalueer deur die reaksie van plaatjies
aan endogene agoniste wat ADP en AA by wisselende konsentrasies insluit te ondersoek.
Results: Hierdie studie het getoon hoër basislyn vlakke van CD62P uitdrukking in behandeling
naïewe MIV-positiewe pasiënte in vergelyking met onbesmette beheermaatreëls (beteken%
CD62P 71,74 ± 2,18 vs beheer 54,52 ± 2,42, p <0.0001). Daar is ook getoon dat% CD62P
uitdrukking direk gekorreleer met plaatjie tellings (r = 0,374, p = 0,042). Plaatjie tellings het 'n
omgekeerde korrelasie met virale ladings (gee waardes) fibrinogeen vlakke korreleer met die
absolute WCC (r = 0,659, p = 0,0021), absolute neutrofiel telling (r = 0,619, p = 0,0105);
absolute monosiet telling (0,562, p = 0,0235) en hsCRP (r = 0,688 p = 0,0011). Daarbenewens,
fibrinogeen het 'n sterk negatiewe korrelasie met 'n CD4-tellings (r = -0,594, p = 0,0014) en
daarom kan 'n waardevolle merker van beide die siekte en die risiko van trombose in
behandeling naïewe MIV-positiewe pasiënte. HsCRP vlakke gekorreleer met die absolute
neutrofiel tellings (r = 0,392, p = 0,0005). Die MIV-groep het 'n algehele hiper-reaksie op die
ADP by 'n konsentrasie 0,025 μM in vergelyking met onbesmette beheermaatreëls (62,34 ± 9,7
vs beheer 36,90 ± 5.7, p = 0,0433).
Gevolgtrekkings: In hierdie studie beskryf ons 'n roman vloeisitometrie tegniek wat gebruik kan
word om die vlakke van Plaatjie aktivering en plaatjie funksie in die MIV-besmette pasiënte te
evalueer. Verder het ons 'n verslag van 'n koste-effektiewe paneel in die vorm van fibrinogeen,
WCC en plaatjies wat waardevol kan wees in die voorspelling van die vordering van MIVinfeksie
tot VIGS of ander inflammatoriese-verwante komplikasies in die behandeling naïewe
MIV-besmette pasiënte. Plaatjie tellings het 'n omgekeerde korrelasie met die virale laste en 'n
direkte verband met die vlak van geaktiveerde bloedplaatjies. Hierdie bevindinge saam, dui op
die moontlike prognostiese waarde van Plaatjie aktivering en die plaatjie tel in die konteks van
die asimptomatiese MIV-geïnfekteerde pasiënte. Ons bevindinge dui daarop WCC en fibrinogeen kan gebruik word om die inflammatoriese profiel van individuele MIV-geïnfekteerde
pasiënte te evalueer. Dit kan 'n direkte impak op MIV pasiënt vooraf aan die inisiasie van
antiretrovirale terapie en waardevolle in die monitering van die reaksie op behandeling. Verder
bied ons 'n roman vloeisitometrie gebaseer plaatjie funksionele toets en dui op die gebruik van
die ADP teen 'n konsentrasie van 0,025 μM plaatjie funksie optimaal te evalueer in MIVgeïnfekteerde
pasiënte. Die benutting van die roman vloeisitometrie tegniek soos beskryf in
hierdie studie sal 'n beduidende waarde toevoeg in die beoordeling van die die trombotiese
risiko en die siekte in MIV-geïnfekteerde pasiënte en kan addisioneel bewys van waarde te
wees in 'n ander chroniese inflammatoriese toestande. / National Reserach Foundation
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