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THE HEALTH AND NUTRITIONAL STATUS OF HIV POSITIVE WOMEN (25-44 YEARS) IN MANGAUNG.Hattingh, Zorada 30 September 2005 (has links)
Human Immunodeficiency Virus infection causes Acquired Immune Deficiency Syndrome, which
has caused millions of deaths, with more expected, particularly in developing countries like South
Africa, where poverty is a critical factor.
The intake, digestion, absorption and metabolism of food and nutrients emerge as a vicious cycle.
The undernourished HIV-infected individual develops micronutrient deficiencies,
immunosuppression and oxidative stress, thereby accelerating disease progression. Symptoms
include weight loss and wasting, with increased risk of secondary infections.
A representative sample of 500 African women (25-34 and 35-44 years) from Mangaung in South
Africaâs Free State Province participated in the study.
Socio-demographic composition and physical activity levels were determined by questionnaire.
Weight, height, circumference (waist and hip) and bioimpedance measurements were used to
calculate body mass index and fat distribution and percentage. Dietary intake was determined
using a food frequency questionnaire, and nutrient intake was analysed. Biochemical nutritional
status was determined through blood samples.
Socio-demographic characteristics indicated high unemployment rates. Significantly more HIV
positive than HIV negative young women had lived in urban areas for over ten years, and smoked
and/or used nasal snuff. Few young women had no education, while more older women had only
a primary school or Grade 8-10 education. Significantly more younger and older HIV positive
women headed their own households. No significant differences were found in housing conditions,
room density and household facilities of younger and older HIV positive and HIV negative women.
Anthropometric results showed that approximately 50% of all women were overweight/obese.
Most women had a gynoid fat distribution and were fat/obese according to fat percentage.
However, young HIV positive women had significantly lower body mass index and fat percentage
than young HIV negative women. The entire sample had low physical activity levels.
Median dietary intakes of energy, macronutrients and cholesterol were high, with young HIV
positive women having a significantly higher median energy intake than young HIV negative
women. Low median intakes of calcium, total iron, selenium, fat-soluble vitamins, folate and
vitamin C, but high median intakes of the B vitamins, were reported overall. Younger women with
HIV had significantly higher intakes of calcium, phosphorus, potassium, and vitamins B12, D and E
than young HIV negative women. Older HIV positive women had significantly lower intakes of
haem iron, nonhaem iron and selenium than older HIV negative women.
Although median values for most biochemical parameters were normal, younger HIV positive
women had significantly lower median haemoglobin and haematocrit levels, while older HIV
positive women had significantly higher serum ferritin and lower transferrin values than their HIV
negative counterparts. Significantly more HIV positive younger and older women had low
haematocrit values, while significantly more HIV negative older women had low serum iron and
high transferrin concentrations. Compared to HIV negative women, younger and older HIV positive
women had significantly lower median blood values for total lymphocytes and serum albumin, but
significantly higher median blood levels of total serum protein. Plasma fibrinogen and serum
insulin concentrations were significantly reduced in young HIV positive women. Older HIV positive
women had significantly lower total serum cholesterol values than older HIV negative women.
Serum glucose and serum triglycerides did not differ significantly between HIV positive and HIV
negative women within both age groups.
In younger and older women, increased serum total protein and decreased serum albumin were
associated with HIV infection. In younger women, smoking and being unmarried increase the odds
of HIV infection, while in older women a higher education level and a decreased non-haem iron
intake are associated with HIV infection.
An adequate diet, nutritional counselling and active physical activity can improve immune function,
quality of life and biochemical nutritional status. Dietary intake alone, however, may be insufficient
to correct nutritional deficiencies in this poor community, and the role of food-based approaches
and micronutrient supplementation merits further attention.
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THE EFFECT OF SELECTED POLYMORPHISMS IN THE P53 PATHWAY AS POTENTIAL GENETIC MODIFIERS OF CANCER RISK AND PENETRANCE IN FEMALE AFRIKANER BRCA2 CARRIERSDajee, Bhavini Kiran 15 February 2010 (has links)
Germline mutations in BRCA2 confer a high risk for the development of breast
cancer in the Afrikaner population. A great deal of variability in the development of
the disease has been observed among mutation positive family members.
Evidence suggested that genes affecting breast cancer risk in the general
population could potentially also affect breast cancer risk in BRCA mutation
carriers. The cell cycle control pathway was selected as a candidate as the
functional loss of the tumour suppressor protein p53 is a common feature in diverse
human cancers. The ability of this protein to sense cellular damage and halt the
progression of the cell cycle or direct the cells to apoptosis is essential in
preventing tumourigenesis.
The aim of the study was an attempt to identify potential genetic modifiers of breast
cancer risk and penetrance in Afrikaner women carrying the South African founder
BRCA2 c.8162delG mutation. It involved environmental factors as well as six
polymorphisms detected in critical genes of the Tp53 pathway. The investigated
polymorphisms included three variants previously detected in Tp53 (intron 3, exon
4 and intron 6), a polymorphism present in the promoter of MDM2 and two SNPs
identified in WAF1 (intron 2 and exon 2).
The epidemiological study failed to identify any specific characteristic associated
with an increased or protective breast cancer risk and did not explain the observed
residual variation. Of the six polymorphisms studied, only one proved to be
statistically significant, namely the 5â splice-site variant in intron 2 of WAF1. This
polymorphism seemed to explain the variation in penetrance for some of the
families, but needs to be confirmed by more extensive studies. A breast cancer
recombinant haplotype was compiled using the most informative variants, namely
the polymorphism in the MDM2 promoter, the 5â splice-site variant in intron 2 of
WAF1 and the SNP in exon 4 of Tp53, but proved to be uninformative. Association
studies including gene to gene and gene to environment interactions could assist
researchers in their understanding of the mechanistic basis of the polygenic nature
of breast cancer.
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THE EFFECT OF A COMBINATION OF SHORT-CHAIN FATTY ACIDS ON PLASMA FIBRINOGEN CONCENTRATIONS IN WESTERNISED BLACK MENde Wet, Martie 02 December 2009 (has links)
The incidence of the western diseases, atherosclerosis, CHD and stroke is
progressively rising in black populations worldwide and in South Africa. Stroke is an
important cause of death in black populations in South Africa and may increases
even further if risk factor (coronary and some haemostatic risk factors) prevalence is
altered by change in lifestyle and diet, westernisation and migration to an urban
environment. Raised fibrinogen levels which are more prevalent in westernised
black men than white men, are accepted as an important risk factor for stroke and
CHD. It is believed that the possible protective effects of diet against the
development of atherosclerosis and thrombosis could be mediated, in part, through
haemostasis. A prudent low-fat, high-fibre diet may favourably influence
haemostasis. More specifically, oat bran (soluble fibre) has been shown to have
beneficial effects on some coronary risk factors and haemostasis. The physiological
effects of dietary fibre are strongly related to SCFAs, which are produced by colonic
fibre fermentation. According to available literature, SCFAs could possibly have a
beneficial effect on lipid profiles and haemostatic risk factors. Little information is,
however, available on the effect of a specific combination of SCFAs on fibrinogen
levels and other haemostatic factors in human subjects.
The main objective of the study was to examine the effect of a combination of
SCFAs, resembling oat bran (acetate:propionate:butyrate â 65:19:16) on plasma
fibrinogen levels, some haemostatic risk factors and other related risk factors for
CHD and stroke in westernised black men.
The study was a randomised, placebo-controlled, double-blind clinical trial. 22
subjects falling within a pre-determined set of inclusion criteria, and with higher
normal fibrinogen levels were randomly selected into an experimental group (n = 11)
and placebo group (n = 10). Supplementation of 12 capsules daily was sustained for
five weeks. Total plasma fibrinogen, fibrin monomer concentration, fibrin network
properties, factor VII and factor VIII activity, serum lipids, glucose concentrations,
some metabolic indicators and fasting acetate concentrations were measured at
baseline and at the end of supplementation, in all subjects. The usual dietary intake of the subjects was obtained using a food frequency questionnaire and a 24-hour
recall.
According to the baseline results, the subject group was homogeneous with an
apparently healthy clinical and physical appearance. Although both subject groups
had a favourable coronary and haemostatic risk profile, total cholesterol levels as
well as factor VII and factor VIII activity were in the higher normal ranges.
Furthermore, the 24-hour recall indicated a tendency towards the adoption of an
atherogenic Westernised diet. Although SCFA supplementation had no effect on the
fibrinogen concentrations, a significant decrease was observed in the fibrin monomer
concentrations, network fibrin content, factor VII and factor VIII activity. A significant
increase was observed in the compaction of the fibrin networks, as well as a
tendency for the mass to length ratio of the fibrin fibres to increase. Furthermore, a
statistically significant although not clinically significant increase was indicated in
HDL cholesterol concentrations after SCFA supplementation.
It was evident from these findings that SCFA supplementation may have a direct
effect on haemostasis, especially the fibrin network characteristics, factor VII and
factor VIII activities, as well as fibrin monomer concentration. This observation
suggests that SCFA supplementation may have a strong protective effect against
atherosclerosis and thrombosis.
In conclusion, the hypothesis that soluble dietary fibre will influence fibrinogen
concentrations and other haemostatic risk factors through production of SCFAs, was
proven to be partially true. It was clear that, although fibrinogen concentration was
not influenced by SCFA supplementation, beneficial effects on the fibrin network
architecture and the positive cascade effect on haemostasis may be a direct effect of
SCFAs supplementation. The study further indicated that the known protective
effects of dietary fibre on CHD could partially be mediated through effects of SCFAs
on fibrin networks. It is recommended that the role of fibrin networks as a risk factor
for CHD and the effect of diet on haemostasis should be further investigated.
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INFLUENCE OF SELECTED POLYMORPHISMS ON THE EXPRESSION OF BREAST CANCER IN AFRIKANER BRCA2 CARRIERSSchneider, Sue-Rica 23 August 2012 (has links)
The aim of the study was to elucidate the variation in phenotypic expression
observed within BRCA2 c.8162delG mutation positive families. The study
attempted to identify possible genetic factors that contribute to the residual risk
conferred by the BRCA2 founder mutation. As BC is a polygenetic disorder,
polymorphisms within various low penetrance genes may contribute to the
expression of the disease. The selection of the SNPs were based on the results
of the CIMBA consortium and have been proven to be associated with an
increased BC risk in the general population (Easton et al., 2007) and in BRCA2
mutation carriers specifically (Antoniou et al., 2008). Two SNPs (rs2234693
[PvuII] and rs9340799 [XbaI]) present within ESR1 as well as SNPs present in
TNRC9 (rs3803662), LSP1 (rs3817198), MAP3K1 (rs889312) and FGFR2
(rs2981582) identified by GWAS have been implicated in BC risk. These six
polymorphisms have been selected to evaluate the risk within the Afrikaner
BRCA2 8162delG (c.7934del, p.Arg2645AsnfsX3) mutation carriers specifically.
Genotyping of rs2234693 (PvuII) and rs9340799 (XbaI) was done by PCR-RFLP
analysis whereas Taqman® assays were used for genotyping rs3803662
(TNRC9), rs3817198 (LSP1), rs889312 (MAP3K1) and rs2981582 (FGFR2).
Automated allelic discrimination using the BioRad CFX Manager v1.1.308.1111
software were compared to manual discrimination methods to ensure robust
genotyping. Cohenâs kappa analysis suggested a combination of automated
(Method 1) and manual (Method 3) genotyping was best suited for accurate allelic
discrimination except for LSP1. Due to an putative SNP detected within LSP1, the
validity of the LSP1 results should be treated cautiously as no information on the
frequency of the second putative SNP in white European individuals is available. Of the six polymorphisms analyzed, only rs2234693 (PvuII), indicated a possible
association with BC (P-value = 0.0896), which should be explored within a larger
study group. For FGFR2, the HWE results indicated that the deviation observed in
the BRCA2 mutation carrier group could possibly be associated with BC.
Haplotypes compiled for rs2234693 (PvuII) and rs9340799 (XbaI) as well as the
remaining four SNPs were uninformative as it revealed no differences between the
BC patients and the Cases. These results may have been due to the high allelic
heterogeneity observed within the Afrikaner population, as well as the small test
group used..
Although the results of this study did not deliver significant results, it did provide
insight into allelic distributions of the SNPs in the Afrikaner BRCA2 8162delG
(c.7934del, p.Arg2645AsnfsX3) mutation carriers specifically. Larger scale
genotyping could lead to more significant findings to help elucidate the
polygenetic nature of BC with the Afrikaner.
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A biologically informed method for detecting associations with rare variantsMoore, Carrie Colleen Buchanan 05 December 2013 (has links)
Many recent studies have identified rare variants that contribute to common, complex disease. It is believed that rare variants likely have a larger effect size (compared to GWAS findings) and can act alone, in concert with other rare variants, or together with common variants. Multiple rare variants can potentially account for a portion of missing heritability in a given trait; therefore, binning or burden testing, may better account for genetic heterogeneity. BioBin, an innovative collapsing method developed in the Ritchie lab, utilizes a flexible repository of data assembled from multiple public databases.
The novelty of BioBin lies in access to comprehensive knowledge-guided multi-level binning. BioBin can apply multiple levels of burden testing, including: functional regions, evolutionary conserved regions, genes, and/or pathways. BioBin does not include a specific statistical association test, since the application of statistical testing is dependent on data type and analysis in question. Therefore, the user has the flexibility to apply tests appropriately without constraint.
BioBin has been tested in the context of extensive simulation studies, compared with multiple published statistical methods, and applied to the NHLBI GO Exome Sequencing Project for Cystic Fibrosis. BioBin is a very useful and flexible tool to analyze sequence data and can uncover novel associations with complex disease.
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Determining the Use of Electronic Medical Records in Genetic Studies of Multiple SclerosisDavis, Mary Feller 09 December 2013 (has links)
The clinical course of multiple sclerosis (MS) is highly variable, and research data collection is costly and time-consuming. Much is known about the genetic risk of acquiring MS, but little is understood about the effect of genetics on the clinical course. This work uses natural language processing techniques applied to electronic medical records (EMR) to identify MS patients and key clinical traits of disease course. 5,789 individuals with MS were identified by algorithm. Algorithms were also developed with high precision and specificity to extract detailed features of the clinical course of MS, including clinical subtype, presence of oligoclonal bands, year of diagnosis, year and origin of first symptom, Expanded Disability Status Scale scores, timed 25-foot walk scores, and MS medications. DNA was available for 1,221 individuals through BioVU. These samples and 2,587 control samples were genotyped on the ImmunoChip. After extensive sample and SNP quality control, replication of known MS risk loci confirmed that the genetic architecture of this EMR-derived population is similar to that of other published MS datasets. Genetic analyses of seven clinical traits were performed using the data extracted from the medical records: age at diagnosis, age and CNS origin of first neurological symptom, presence of oligoclonal bands, Multiple Sclerosis Severity Score, timed 25-foot walk, and time to secondary progressive MS. No outstanding results were observed, but many interesting results require further investigation. This work shows the potential of using EMR-derived data in research studies of disease course.
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Translating the Fashion Story: Analyzing Fashion Captions in Two Women's Fashion MagazinesVosper-Woghiren, Ehimwenma O 10 December 2013 (has links)
Fashion magazines are the most accessible source for women to learn the latest about fashion and trends. Publishing company Condé Nast owns many consumer fashion magazines including the American editions of Lucky and Vogue. Even though both magazines are classified under the genre of fashion, these magazines are branded differently. Vogue features editorial styling, which is garments arranged lavishly and creatively for the glossy fashion spreads. However, Lucky magazine contains both editorial and lifestyle styling. To reinforce the styled image, fashion magazines place captions in these editorials. Captions transform these garments into written language. Since each magazine uses different types of styling, editors are writing captions in different formats. The purpose of the study is to investigate the stylistic similarities and differences of fashion captions in Lucky and Vogue. Additionally, semantic-syntax tree diagrams were used to determine how the fashion captions communicate meaning.
This study followed a mixed methods approach using a purposive sample (n=14). The March and September issues were examined from 2010-2013. Data results show magazines are written primarily in grammatical modifiers. Different from prior research, nouns were the largest category, and adjectives composed the second largest category. Some captions did not have verbs resulting in mainly a descriptive narrative. Each magazine differed in the types of verbs used, frequency of proper nouns, and types of prepositions. Furthermore, when editors are not telling a fashion story, then captions are written as imperative commands. When telling a fashion story, the garment is often personified to take on human characteristics or described as possessing certain characteristics. Both magazines use these writing styles to convey different ideas and content to the reader.
The results of this study strengthened the belief that a distinct stylistic form of writing exists in fashion captions. From this study, fashion editors and scholars may become more aware of the current stylistic formations featured in fashion captions, and further enhance their knowledge of how to communicate editorial trends and themes to their intended audience.
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Investigation of the genetic epidemiology of age-related macular degeneration, primary open-angle glaucoma, and diabetic retinopathy in diverse populationsRestrepo, Nicole Ann 23 March 2015 (has links)
Common age, related eye diseases are a major driving force behind vision disability and blindness. The three most common diseases afflicting Americans today are age-related macular degeneration (AMD), primary open-angle glaucoma (POAG), and diabetic retinopathy (DR). Much is known about the environmental factors contributing to disease risk and progression in these conditions, but the genetic architecture remains elusive. We performed a meta-analysis of known AMD-related variants and variants in cholesterol pathways in the three major race-ethnicities in the United States, and Chinese and Malay individuals from Singapore. Additionally, we identified potential novel associations between mitochondrial variants and risk of AMD in NHANES Mexican Americans. African American case and control samples for POAG and DR were extracted from the Vanderbilt de-identified electronic medical records system called the Synthetic Derivative. A large subset of these individuals were genotyped on the Illumina Metabochip array. Genetic association analyses were performed to replicate previously identified and novel associations in patients with POAG and separately for patients with DR. Nominally significant associations ( p < 10-4) in POAG analyses suggest that vascular and angiogenic pathways may play a role in POAG risk in African Americans. In the study of DR, variants located in genes known to play a role in epithelial and endothelial tight cellular junctions, wound healing were nominally associated in the Synthetic Derivative African American DR population.
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Examination of Candidate Exonic Variants that Confer Susceptibility to Alzheimer Disease in the AmishD'Aoust, Laura Nicole 27 March 2015 (has links)
Alzheimer disease (AD) is the most common cause of dementia. As with many complex diseases, the identified variants do not explain the total expected genetic risk that is based on heritability estimates for AD. Isolated founder populations, such as the Amish, are advantageous for genetic studies as they overcome limitations associated with complex population studies. Amish AD cases harbored a significantly higher burden of the known risk alleles compared to Amish cognitively normal controls, but a significantly lower burden when compared to cases from a cohort of unrelated individuals. These results suggest that known loci explain some of the genetic effects and that there may be different underlying genetic architectures between the two populations. Whole-exome sequencing of a selected subset of the overall study population was used as a screening tool to identify variants located in the regions of the genome that are most likely to contribute risk. By then genotyping the top candidate variants from the known AD genes and implicated linkage regions from previous studies in the full data set, new associations could be confirmed. The most significant result (p = 0.0012) was for rs73938538, a synonymous variant in LAMA1 within the previously identified linkage peak on chromosome 18, but this association did not generalize when tested in a dataset of unrelated individuals. These results indicate that exonic variation in a majority of previously associated LOAD genes, and regions implicated by previous linkage studies, does not contribute to risk for LOAD in the Amish.
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Genetics of Tuberculosis ResistanceSobota, Rafal Sebastian 13 April 2015 (has links)
One third of the worlds population has been infected with Mycobacterium tuberculosis (MTB). Most of those exposed develop an asymptomatic latent infection. In the absence of co-morbidities, only 5-10% of people progress to active tuberculosis disease (TB) post-exposure, defined as primary TB. However, immunosuppression resulting from malnutrition or human immunodeficiency virus (HIV) co-infection increases the likelihood of both primary TB and activation of a latent infection. As a result, tuberculosis remains a major global health problem. Worldwide, TB is the second-leading cause of mortality from a single infectious agent, after HIV. In 2013, 9 million new cases of clinical tuberculosis were diagnosed and 1.5 million deaths were attributed to the disease. An estimated 360,000 deaths occurred in people co-infected with HIV, and 75% of these cases occurred in sub-Saharan Africa.
MTB infection and tuberculosis disease have a substantial heritable component. In this project, we studied a genetic resistance phenotype to TB disease and MTB infection, as opposed to more standard approaches tailored towards finding loci associated with susceptibility. We recruited HIV-positive patients from three recently concluded prospective cohorts of TB from Uganda and Tanzania. We hypothesized that HIV-positive individuals living in MTB hyperendemic areas who do not develop TB disease represent an extreme resistance phenotype. A study of 175,906 variants in 267 cases and 314 controls revealed a genome-wide significant association of a common TB resistance single nucleotide polymorphism, rs4921437, in the regulatory region of IL12, a gene previously associated with susceptibility. We also hypothesized that HIV-positive individuals who do not establish MTB infection despite living in hyperendemic regions are genetically resistant. In a study of 162,228 variants in 244 cases and 235 controls, we discovered a genome-wide significant association of a resistance variant rs877356 near IL9, a gene previously associated with bronchial hyperresponsiveness and asthma. Furthermore, we evaluated the effects of multi-locus interactions in a candidate gene approach and found that epistasis also plays a significant role in risk of MTB infection and TB disease.
We present a novel approach to genome-wide association studies, also applicable to whole genome sequencing studies, where the use of an extreme resistance phenotype allowed us to identify large effect sizes and attain genome-wide significance in cohorts of a relatively small sample size. The use of HIV status as a central feature of our hypothesis as opposed to a confounder or exclusion criterion is also unique.
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