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Sensitivity and Specificity of the Uniform Field ERG in Glaucoma DetectionHermas, Asma 28 June 2019 (has links)
Glaucoma is a silent disease, and by the time patients are diagnosed, there is a significant vision loss, and the clinicians are left to deal with monitoring the disease progression. Therefore, early glaucoma detection would be the ultimate goal for researchers as well as clinicians. This study assessed the sensitivity and specificity of pattern electroretinography (PERG) and uniform field electroretinography (UF-ERG) in detecting glaucomatous changes using the Diagnosys D-341 Attaché-Envoy Electrophysiology System. One hundred eyes of 50 glaucoma patients, including 42 glaucoma-suspect eyes, and 58 confirmed glaucoma eyes went through ophthalmic examination including PERG, UF-ERG (to measure the photopic negative response (PhNR)), Optical coherence tomography (OCT), and standard automated perimetry (SAP). The results were compared to 72 eyes of 36 healthy control subjects. PERG and PhNR parameters showed a significant decrease in the amplitude and longer latency in glaucoma suspects and glaucoma groups compared to the control group. The PhNR amplitude was more sensitive at detecting glaucomatous changes in the glaucoma suspect group than the PERG in terms of low amplitude. Furthermore, two different PERG tests showed a similar ability to recognize individuals without glaucomatous changes and PhNR amplitude and latency were able to identify people with and without glaucoma-related changes, respectively.
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Evaluating the specancer cell targeting peptides for applications in cancer diagnosticsMazyambe, Margaret Kena January 2013 (has links)
>Magister Scientiae - MSc / Cancer is a disease most often associated with poor prognosis. During the development of the
disease, cells acquire genetic mutations which result in changes in bio-molecules (DNA and
protein), thus altering normal functioning of cells. These bio-molecules can thus serve as
biomarkers for the diagnosis of cancer and can also facilitate the early detection of cancer.
Antibodies labelled with organic fluorophores are typically used in immunohistochemistry
techniques to screen cancerous tissue for the presence of biomarkers. More recently, researchers
started to use cancer specific peptides (e.g LYP-1, RGD,) rather than antibodies for this purpose.
Advantages of peptides include high affinity to their binding target, rapid accumulation at target
sites and the ability to evade the immune system. Fluorescent nanocrystals or quantum dots are
emerging as nanoparticles that can replace organic fluorophores. Several properties of quantum
dots make these nanoparticles an ideal application in the detection of cancer related biomarkers.
These include size tunable fluorescence emission, resistance to photobleaching as well as high
quantum yields that result in bright emission of fluorescence. The aim of this research project was
to investigate the specific binding of selected peptides to cancer cells using functionalized quantum
dots. Since the cost of synthetic peptides are so high, the aim of this study was also to express these peptides in E.coli bacterial cells. Cancer targeting peptides were identified from literature
and oligonucleotides with sequences encoding these peptides were designed. Four
oligonucleotides encoding the peptides p6.1, p.L, MV and NL1.1 were successfully cloned using
the pET21b plasmid vector. However, the peptides were not successfully expressed in E.coli.
Cancer targeting peptides namely p.C, p.H, p.L, p6.1 and Frop-1 were chemically synthesized and
obtained from GL biochem (Shanghai). These peptides were conjugated to quantum dots (Qdot
525) using 1-ethyl-3-(3-dimethylamino) carbodiimide HCl (EDC) chemistry. The peptidequantum
dot conjugates were applied to cancer cells to achieve specific binding. The Kmst-6 noncancerous
cell line served as a control. The binding of the peptide-quantum dot conjugates was
analyzed using flow cytometry and fluorescence microscopy. The p.H peptide revealed the highest
binding affinity to cancer cells as indicated by fluorescence intensity. This was followed by the
p.C peptide which showed differential binding amongst the cancer cell lines. The Frop-1 peptide
displayed the lowest binding affinity, while the binding affinity of the peptides to Kmst-6 cell lines
was very low. This study demonstrated that the cancer targeting peptides used in this study bind
to cancer cells and that the specificity with which these peptides bind to the cells depends on the
cell types and the peptide
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From policy to implementation: a needs-based budget program for implementing the cervical cancer screening policy in South AfricaRobertson, Jamela Ellen 16 April 2015 (has links)
A Dissertation submitted to the Faculty of Health Sciences, School of Public Health,
University of the Witwatersrand, to fulfil the requirement to acquire a degree of
Master of Science in Medicine
Johannesburg
30 September 2014 / Background
In South Africa cervical cancer has an age standardised incidence rate of 23 per 100
000 in women below the age of 35 and 76 per 100 000 amongst women over 35.
The National Department of Health (NDoH) introduced the national cervical cancer
screening policy guidelines in 2000, with the aim to screen 70% of women aged
between 30 and 59 over a 10-year period. Health managers at provincial and district
level were expected to implement this policy at their respective levels. Research has
shown that implementing national health policies is often challenging due to
management weaknesses, including the lack of guidelines or tools on how managers
should plan and allocate budget for services.
Aim
The aim of this study is to develop and test an approach to planning and budgeting
that would assist health managers to follow a rational process to plan and estimate
budget requirements for implementing the cervical cancer screening policy at subnational
level.
Method
This study was conducted in three districts in South Africa. The study was conducted
in four phases. A situational analysis of budgeting practices was conducted in the
first phase, to describe existing planning and budget allocation practices for cervical
cancer screening programmes in the study sites and identify any existing gaps. The
process requirements for implementing a cervical cancer screening programme were
then identified prospectively in the second phase. Informed by the situation analysis
and the process requirements, a computer-based planning and budget estimation
program was developed in the third phase and tested through interviews with key
informants in the fourth phase of the study.
Results
The situational analysis revealed a lack of involvement of interviewed programme
managers at all the levels, in planning and budgeting for implementing cervical
cancer screening programmes. The participants’ descriptions of budget allocation
processes indicated that there was no defined process for allocating budget to
services and the allocations were not specifically informed by assessed programme
needs in their respective areas of jurisdiction.
Process requirements for cervical screening were identified and documented for the
following aspects of a cervical screening programme: calculating target population to
inform planning for service provision, staff and equipment audits, equipment and
supplies, material required for systems functioning (e.g., tools, forms, guidelines),
transport and communication systems, community information education and
communication (IEC) strategies, staff training, laboratory services and services for
the treatment of High grade Squamous Intraepithelial Lesions (HSIL). A computerbased
planning and budget estimation program, which could enable managers to
define and quantify resources needed to implement a cervical screening programme
was developed, informed by the documented process requirements.
The testing of the computerised planning and budget estimation program indicated
that the program could improve planning and help managers to estimate budget
requirements for implementing cervical screening. Respondents indicated that the
program was relatively easy to use and also felt that it could potentially be useful for
programme planning as follows: a) it could serve as a tool for programme needs
assessment, b) it could facilitate rational budget estimations, c) managers could use
it as a bottom-up tool to motivate for resources, and d) managers could use it to
refute inadequate budget allocations where possible.
Conclusion
The findings of the situational analysis support existing literature in revealing very
little if any change in relation to inherent challenges in implementing cervical cancer
screening services in South Africa. The findings of this study are relevant for public
health programme planning and budgeting beyond cervical screening. Since
managers at sub-national level are delegated to implement policy, it is imperative
that they are provided with tools that may guide them to plan and budget for services
on the basis of needs in their areas of jurisdiction. This study provides one such
tool.
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Improving earlier non-invasive diagnosis of high-grade serous ovarian cancerMoore, Elizabeth January 2018 (has links)
The majority of women with ovarian cancer (OC) have advanced disease at diagnosis and 5-year survival rates of less than 25%. Women with stage I disease have significantly better 5-year survival rates of over 90%. Recent large studies using CA 125 and transvaginal ultrasound have failed to improve mortality in a screened population. There is therefore a pressing need for new diagnostic biomarkers in OC. The primary aim of my project, as a first step in developing a diagnostic circulating tumour DNA (ctDNA) biomarker for high grade serous ovarian cancer (HGSOC), was to investigate low-cost high-throughput next generation sequencing assays in plasma samples collected from women with newly diagnosed OC. The secondary aim was to apply these methods to other non-invasive samples including cervical liquid based cytology samples that might contribute to earlier diagnosis or screening for women with OC. ctDNA was detected in 30-49% of women with newly diagnosed OC from the UKOPS (n=54) and CTCR-OV04 (n=156) cohorts using targeted sequencing. Using the trimmed median absolute deviation (t-MAD) score, a quantitative measure of genome wide copy number aberration generated from shallow whole genome sequencing (sWGS) data, ctDNA was detected in 39-41% of the women with newly diagnosed disease. To improve sensitivity of ctDNA detection I developed an optimised method for targeted sequencing that has the potential to lower the limit of detection of ctDNA in HGSOC by 100 fold. I have also shown that the size profile of HGSOC ctDNA fragments is different to that of wildtype DNA fragments and shown that selecting for DNA fragments between 90-150 bp can increase rates of ctDNA detection in HGSOC. ctDNA detection increased to 53-67% of women with newly diagnosed OC using the size selected t-MAD score. I have evaluated the utility of cervical sampling for earlier diagnosis of OC by testing and optimising DNA extraction, library preparation and sequencing methods. I have detected tumour DNA in routine cervical cytology samples collected from women subsequently diagnosed with cervical and endometrial cancers. In summary I have developed methods for ctDNA detection in women with newly diagnosed HGSOC that can be applied and refined in larger prospective studies of women undergoing follow-up for treated HGSOC, women with symptoms suggestive of OC and women at high risk of OC.
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An investigation into the localization of peptide-gold nanoparticles in an in vitro and in vivo colorectal cancer modelCairncross, Lynn Unknown Date (has links)
Background: Colorectal cancer is the third most common cancer and cause of related deaths worldwide. Early colorectal cancer diagnosis is vital in reducing incidence and mortality. There is a need for the development of non-invasive screening tools for enhancing the detection of the disease. Cancer specific peptides are useful cancer targeting agents that can be used to specifically improve early detection strategies. Several cancer targeting peptides have been identified. Previous work investigated the specific binding of three of these peptides (p.C, p.L and p.14) conjugated to quantum dots and were found to bind to colorectal cancer cell lines (HT-29 and Caco-2). However, their uptake, localization and biodistribution in an in vitro and in vivo colorectal cancer model have not been determined. This is essential in gaining an understanding for future diagnostic or therapeutic based applications. Primary Aim: The aim of this study was investigate the localization of three selected peptides p.C, p.L and p.14 conjugated to gold nanoparticles in an in vitro and in vivo colorectal cancer model using HRTEM. Methodology: The AuNP/peptide conjugates were characterized by HRTEM and DLS. For in vitro studies; HT-29, Caco-2 and C3A cells were exposed to the AuNP-p.C, AuNP-p.L and AuNP-p.14, collected and processed for HRTEM to assess targeting and localization. For in vivo studies; the establishment of a colorectal cancer model using the AOM/DSS model 1 and 2 was conducted. Wistar rats were assigned to 6 groups, five experimental and 1 control group. Group 1 received AOM/DSS method 1 and was treated with AuNP-p.L. Group 2 and 3 received AOM/DSS method 2 and were treated with AuNP-p.C and AuNP-p.14. Group 4 and 5 remained healthy and treated with AuNP-p.C and AuNP-p.14. Group 6 remained healthy receiving no nanoparticle treatment. After treatment, rats were sacrificed and tissue was processed for HRTEM. Tissue chosen for HRTEM analysis included: Group 1 (inflamed colon, rectum, pancreatic and kidney), Group 4 (kidney) and Group 5 (liver). Results: results obtained from nanoparticle characterization suggested that nanoparticles were conjugated to their respective peptides and were stable in dispersion. For in vitro studies, results suggested no AuNP targeting and localization in HT-29 cell lines. For in vivo studies, no colorectal cancer tumours were induced. TEM micrographs did not indicate the presence of nanoparticles in colon, rectum, pancreatic, kidney and liver tissue. However, AuNPs were found in the kidney tissue (group 4). Conclusion: Although the overall objectives were not met, this study provided insight into TEM cell preparation and optimization for future nanoparticle cell interaction research. This study also demonstrated the absence of AuNPs in healthy tissue and the presence of AuNPs in healthy kidney tissue through renal clearance, a favourable quality for diagnostic or therapeutic applications.
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Cancer biomarkers, and novel techniques for detectionJamal, Tameem 02 November 2017 (has links)
Technologies for early detection of tumors is critical for better therapy outcome and overall change in cancer survival. These assays must be capable of detecting tumors at early stages in order to prevent metastasis of the tumor and help reduce mortality. Biological molecules can serve as markers that can indicate the presence of cancerous cells. Current biomarkers approved by the FDA include CA 125, which is a tumor associated antigen (TAA). However, the sensitivities of these TAAs is not high enough to detect at early stages of disease. Recent technologies have found that antibodies that recognize these TAAs, also known as autoantibodies, provide more sensitive means to screen for tumors. This review aims to present recent literature data relative to the field of cancer diagnosis and treatment. However, one should note that this article covers only fraction of the broad science behind this subject.
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Efeitos da aplicabilidade de um manual educativo para aÃÃes de detecÃÃo precoce do cÃncer de mama. / The effects of the application of an educational handbook for actions in early detection of breast cancer.Anna Paula Sousa da Silva 02 April 2012 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O controle do cÃncer de mama fundamenta-se no mapeamento do risco, no planejamento e na implementaÃÃo de aÃÃes que visam à detecÃÃo de tumores cada vez menores, proporcionando melhorar a assistÃncia à saÃde, diminuindo os gastos desnecessÃrios e estimulando o desenvolvimento de estratÃgias educativas. Objetivou-se avaliar os efeitos da aplicaÃÃo de um manual educativo relacionado aos exames de detecÃÃo precoce do cÃncer de mama para mulheres. Trata-se de um estudo quase-experimental, realizado no municÃpio de Fortaleza-Ce em uma Unidade BÃsica de SaÃde. A populaÃÃo do estudo foi composta por mulheres cadastradas na referida unidade que realizaram o exame de prevenÃÃo ginecolÃgica, nos meses de abril e maio de 2011, destinados para a primeira etapa da coleta de dados, sendo baseada no nÃmero de atendimentos ginecolÃgicos mensais, totalizando uma amostra de 294 mulheres, distribuÃdas equitativamente em grupo intervenÃÃo-GI e grupo controle-GC. A coleta de dados foi feita atravÃs de uma entrevista por meio de um formulÃrio do tipo inquÃrito CAP (conhecimento, atitude e prÃtica), elaborado baseado no conhecimento dos exames de detecÃÃo precoce e na realizaÃÃo correta dos mesmos, alÃm de caracterÃsticas sÃcio-demogrÃficas das participantes e informaÃÃes sobre fatores de risco para cÃncer de mama nestas mulheres. O estudo foi desenvolvido em duas fases para o GI (inquÃrito CAP prÃ-intervenÃÃo acompanhado de uma sessÃo educativa do manual com leitura posterior dos mesmos pelas participantes e consulta de retorno com preenchimento do inquÃrito CAP pÃs-intervenÃÃo) e, uma fase para GC (inquÃrito CAP). O material educativo aplicado trata-se de um manual de orientaÃÃes a mulheres mastectomizadas onde foram utilizados os dois primeiros capÃtulos que correspondem a explicaÃÃes voltadas para os exames de detecÃÃo precoce. Para a anÃlise estatÃstica, utilizou-se o programa SPSS versÃo 16.0 e os dados foram tabulados, processados e analisados, em tabelas. Os testes estatÃsticos foram selecionados de acordo com a necessidade da anÃlise dos dados, a fim de alcanÃar os objetivos propostos, com confiabilidade e validade do instrumento. ApÃs anÃlise dos dados observou-se a homogeneidade dos dois grupos, mostrando a associaÃÃo das variÃveis sociodemogrÃficas e das variÃveis relacionadas aos fatores de risco para o desenvolvimento de cÃncer de mama. Contudo, puderam-se observar diferenÃas significativas nos escores, no que se refere ao grau de conhecimento, atitude e a prÃtica em relaÃÃo à realizaÃÃo dos exames de detecÃÃo precoce do cÃncer de mama, quando comparados apÃs aplicaÃÃo da intervenÃÃo educativa, notando-se que o grupo intervenÃÃo pÃs-manual mostrou a maioria das variÃveis comparativas superiores Ãs do grupo controle e Ãs do grupo intervenÃÃo antes do manual, isto Ã, apÃs a aplicaÃÃo do manual educativo, houve mudanÃas significantes voltadas para o diagnÃstico precoce do cÃncer de mama. O estudo tornou-se relevante à medida que propÃs avaliar uma estratÃgia de educaÃÃo em saÃde, a fim minimizar as lacunas do conhecimento e a realizaÃÃo dos exames de detecÃÃo precoce do cÃncer de mama e, dessa forma, melhorar a assistÃncia à saÃde mamÃria. Nesse sentido, comprova-se a tese de que a intervenÃÃo educativa, com a utilizaÃÃo de um manual educativo sobre detecÃÃo precoce do cÃncer de mama para mulheres, possibilitou importantes resultados na promoÃÃo da saÃde mamÃria, atravÃs da prevenÃÃo secundÃria. / The control of breast cancer is based on risk mapping, planning and implementation of actions aimed to detect increasingly smaller tumors, providing better health care, reducing unnecessary spending and stimulating the development of educational strategies. The objective was to assess the effects of the application of an educational handbook related to early detection tests of breast cancer for women. This is a quasi-experimental study carried out in Fortaleza-CE, Brazil, in a Basic Health Unit. The study population consisted of women registered in this unit who underwent preventive gynecological examination in April and May 2011, intended for the first stage of data collection, being based on the number of gynecologic examination per month, totaling a sample of 294 women, equally distributed in intervention group and control group. Data collection happened through an interview by a KAP (knowledge, attitude and practice) survey, developed based on knowledge of early detection tests and the correct performance of them, as well as socio-demographic characteristics of participants and information about risk factors for breast cancer in these women. The study was developed in two phases for the intervention group (pre-intervention KAP survey followed by an educational session of the manual and later reading by the same participants and a return visit to post-intervention KAP), and a phase for the control group (KAP survey). The educational material used is a manual of guidelines for mastectomized women where we used the first two chapters that correspond to explanations focused on early detection tests. For statistical analysis we used SPSS program version 16.0 and data was tabulated, processed and analyzed in tables. Statistical tests were selected according to the need for data analysis, in order to achieve the proposed objectives, with reliability and validity of the instrument. After data analysis we observed the homogeneity of both groups, showing the association of socio-demographic variables and variables related to risk factors for developing breast cancer. However, we could verify significant differences in scores, regarding the degree of knowledge, attitude and practice on the performance of examinations for early detection of breast cancer, when compared after application of the educational intervention, noticing that the post-manual intervention group presented most of the comparative variables higher than the control group and the intervention group before the handbook, which means, after the implementation of an educational handbook, there were significant changes addressed at early diagnosis of breast cancer. The study became relevant once it proposed to assess a health education strategy, in order to minimize the gaps in knowledge and performance of the examinations for early detection of breast cancer, thus improving breast health care. In this sense, we prove the thesis that the educational intervention using an educational handbook on early detection of breast cancer for women, allowed significant results in promoting breast health through secondary prevention.
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The prevalence of preclinical atherosclerosis in a healthy adult populationGriffith, Garett J. 03 May 2014 (has links)
Cardiovascular disease (CVD) is a progressive disease that presents signs, such as abnormal thickening or stiffening of arteries, early in its preclinical stage, and screening tools such as carotid intima media thickness (CIMT) measurement and pulse wave velocity (PWV) assessment have the potential to identify individuals prior to the clinical manifestation of CVD. The purpose of this study was to determine the prevalence of preclinical atherosclerosis, as indicated by high CIMT and PWV values, in an adult population aged 40-70 years and free of diagnosed CVD using these screening tools. Secondarily, this study aimed to compare established CVD risk factors and other health parameters between those with elevated or normal arterial health values. Sixty subjects made 2 visits to the Ball State University Human Performance Laboratory. The first visit included basic anthropometric measurements as well as assessment of CIMT and PWV. After a one week objective physical activity assessment, subjects returned to the HPL for assessment of blood lipids and body composition via dual energy x-ray absorptiometry scan. Prevalence of preclinical atherosclerosis was calculated from the total sample as well as within both genders, and an independent samples t-test was conducted in order to identify significant differences in health characteristics between those in the normal and high groups. Abnormal CIMT or PWV values were present in 43% of study subjects; 30% and 18% of the test sample met the criteria for elevated CIMT and PWV, respectively. Significant differences existed between normal and high CIMT and PWV study groups for physical activity, body composition, and blood lipid profile variables. Comparisons within each gender revealed differences in health profile elements. Both the CIMT and PWV measurement techniques may be valuable additions for community CVD screenings, as certain health profile abnormalities may impact each marker of arterial health differently. Additional research is needed in order to determine the cost-effectiveness of these screening tools as a preventive health method. / School of Physical Education, Sport, and Exercise Science
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Cancer Autoantibody Biomarker Discovery and Validation Using Nucleic Acid Programmable Protein ArrayJanuary 2015 (has links)
abstract: Currently in the US, many patients with cancer do not benefit from the population-based screening, due to challenges associated with the existing cancer screening scheme. Blood-based diagnostic assays have the potential to detect diseases in a non-invasive way. Proteins released from small early tumors may only be present intermittently and get diluted to tiny concentrations in the blood, making them difficult to use as biomarkers. However, they can induce autoantibody (AAb) responses, which can amplify the signal and persist in the blood even if the antigen is gone. Circulating autoantibodies is a promising class of molecules that have potential to serve as early detection biomarkers for cancers. This Ph.D thesis aims to screen for autoantibody biomarkers for the early detection of two deadly cancer, basal-like breast cancer and lung adenocarcinoma. First, a method was developed to display proteins in both native and denatured conformation on protein array. This method adopted a novel protein tag technology, called HaloTag, to covalently immobilize proteins on glass slide surface. The covalent attachment allowed these proteins to endure harsh treatment without getting dissociated from slide surface, which enabled the profiling of antibody responses against both conformational and linear epitopes. Next, a plasma screening protocol was optimized to significantly increase signal to noise ratio of protein array based AAb detection. Following this, the AAb responses in basal-like breast cancer were explored using nucleic acid programmable protein arrays (NAPPA) containing 10,000 full-length human proteins in 45 cases and 45 controls. After verification in a large sample set (145 basal-like breast cancer cases / 145 controls / 70 non-basal breast cancer) by ELISA, a 13-AAb classifier was developed to differentiate patients from controls with a sensitivity of 33% at 98% specificity. Similar approach was also applied to the lung cancer study to identify AAbs that distinguished lung cancer patients from computed-tomography positive benign pulmonary nodules (137 lung cancer cases, 127 smoker controls, 170 benign controls). In this study, two panels of AAbs were discovered that showed promising sensitivity and specificity. Six out of eight AAb targets were also found to have elevated mRNA level in lung adenocarcinoma patients using TCGA data. These projects as a whole provide novel insights on the association between AAbs and cancer, as well as general B cell antigenicity against self-proteins. / Dissertation/Thesis / Doctoral Dissertation Biological Design 2015
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Evaluation and Optimization of Quality of Service (QoS) In IP Based NetworksGhimire, Rajiv, Noor, Mustafa January 2010 (has links)
The purpose of this thesis is to evaluate and analyze the performance of RED (Random Early Detection) algorithm and our proposed RED algorithm. As an active queue management RED has been considered an emerging issue in the last few years. Quality of service (QoS) is the latest issue in today’s internet world. The name QoS itself signifies that special treatment is given to the special traffic. With the passage of time the network traffic grew in an exponential way. With this, the end user failed to get the service for what they had paid and expected for. In order to overcome this problem, QoS within packet transmission came into discussion in internet world. RED is the active queue management system which randomly drops the packets whenever congestion occurs. It is one of the active queue management systems designed for achieving QoS. In order to deal with the existing problem or increase the performance of the existing algorithm, we tried to modify RED algorithm. Our purposed solution is able to minimize the problem of packet drop in a particular duration of time achieving the desired QoS. An experimental approach is used for the validation of the research hypothesis. Results show that the probability of packet dropping in our proposed RED algorithm during simulation scenarios significantly minimized by early calculating the probability value and then by calling the pushback mechanism according to that calculated probability value. / +46739567385(Rajiv), +46762125426(Mustafa)
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