<p>Obesity is today a problem that has reached epidemic proportions. One of the causes of obesity is the over-consumption of energy. Fat is the most energy-dense nutrient, where the quality seems to be more important for the development of the metabolic diseases than the quantity. The fatty acid composition in serum lipid fractions can be used to mirror the dietary fat quality.</p><p>Stearoyl-CoA-desaturase (SCD) is an enzyme that converts saturated to monounsaturated fatty acids. A surrogate measure of SCD activity can be estimated as a fatty acid ratio; 16:1/16:0 (palmitoleic acid/palmitic acid) and 18:1/18:0 (oleic acid/stearic acid). The aim of this project was to investigate the intra-day variation in the SCD-ratio in humans eating a standardized diet. The results showed that triacylglycerol and nonesterified fatty acid fractions in serum lipids had a significant variance in the 16:1/16:0 ratio during the day, whereas 18:1/18:0 ratio in the same fractions did not exhibit the same pattern. In this study 16:1/16:0 ratio also seems to be a better marker than 18:1/18:0 ratio for estimating SCD activity. For further evaluation of the intra-day variation there need to be a more long-term study of the SCD-activity for a larger group of subjects.</p>

OBJECTIVE: The main aim of this thesis was to investigate the role of nutrition during "early" HIV-infection in African women. METHODS: Data reported in this investigation formed part of two cross-sectional studies, the THUSA and Mangaung studies. The Mangaung study investigated women and, therefore, the sub-sample of the THUSA study was chosen accordingly. The data of the two studies were kept and analysed separately. The investigation consisted of 1040 women from the THUSA study, aged between 15 and 90 years of which 120 (11.5%) were HIV infected. The Mangaung study comprised of 488 women aged between 25 and 44 years of which 248 (51%) women were infected. Demographic data, anthropometric measurements, health outcome variables and habitual nutrient intakes by a quantified food frequency questionnaire were used. The SPSS statistical package (version 14.0; SPSS Inc., Chicago, Illinois, 2005) was used to analyse data. Descriptive statistics were done expressing variables as means, medians, standard deviations (SD), standard errors (SE) and confidence intervals (CI). An analysis of variance (ANOVA) was done to test for significance between the HIV-infected and non-infected groups in both studies. Partial correlations were done in the infected and non-infected groups to determine associations between dietary / nutrient intake, anthropometry and the biological health variables. In the THUSA study we controlled for age, education level, degree of urbanization and alcohol intake and in the Mangaung study for age, education level and alcohol intake. Nutrient intakes of both infected and non-infected women above and below median values as well as in the first and fourth quartile of total cholesterol (TC) and albumin distribution were compared to assess the role of nutrients in the observed decreases in TC and albumin of HIV-infected women. RESULTS AND DISCUSSION: The dietary intakes of the HIV-infected women in both the studies did not differ significantly from the non-infected women. Total serum cholesterol, albumin, fibrinogen and blood pressure were significantly lower in the HIV-infected women in both the THUSA and Mangaung studies. The non-infected THUSA women with lower serum cholesterol levels (than the median) had significantly lower intakes of percentage energy from fat (25.2 versus 26.4%, p ≤0.027), percentage energy from total protein (11.6 versus 12.1%, p≤0.000), animal protein (25.6 versus 27.7g, p≤0.005), and significantly higher intakes of plant protein (32.2 versus 29.4g, p≤0.002) and fibre (16.9 versus 15.89 p≤0.029). There were no significant differences observed in the nutrient intakes in the infected women with serum cholesterol levels above and below the median. In the Mangaung study no significant nutrient intake differences were observed in both of the HIV-infected and non-infected women with lower and higher than the median TC levels. In the THUSA study, higher intakes of fat (percentage energy) were close to significant (27.3 versus 24.5%, p≤0.053) in the infected women with higher (than the median) albumin levels. In the non-infected group with higher albumin levels, significant differences were observed in percentage energy from fat (26.6 versus 24.9%; p≤0.001) protein (12.2 versus 11.6%; p≤0.001) and carbohydrate (62.8 versus 65.2%; p≤0.000). Higher intakes of saturated fat (SATFAT) (17.7 versus 16.1g, p≤0.008), monounsaturated fats (MUFAT) (19.3 versus 17.4g, p≤0.004) as well as higher intakes of animal protein (28.5 versus 24.4g, p≤0.000) were observed in the group with higher than the median levels of serum albumin. In the Mangaung study the HIV-infected women (with higher than the median serum albumin levels), had significantly higher intakes of energy (13 275 versus 11 622 kJ, p≤0.022), polyunsaturated fatty acids (32.3 versus 17.3g, p≤0.036), dietary cholesterol (412.9 versus 344.5mg, p≤0.043) and plant protein (42.3 versus 35.3g, p≤0.008). No differences were observed in the non-infected women. The further analyses, comparing the dietary intakes in both studies of infected and non-infected women with TC and albumin levels in the first and fourth quartiles, showed that in the THUSA study, non-infected women with lower TC levels had significantly lower intakes of protein (% of total energy), total fat (% of total energy) and vitamin B12 and significantly higher intakes of total energy (TE), plant protein, total carbohydrate, % TE from carbohydrate, dietary fibre, added sugar and thiamine. In the infected women saturated fatty acids (SATFAT), calcium and the fat ratio (polyunsaturated/saturated ratio) differed significantly between women with TC levels in the first and the fourth quartile. A significant higher intake of riboflavin was seen in the non-infected women from Mangaung with TC levels in the fourth quartile, while significant higher intakes of energy, total protein, animal protein, total fat, SATFAT, MUFAT, total carbohydrate, phosphorus, chromium and iodine was seen in the infected women with TC levels in the fourth quartile. These results suggest that a more "westernized" diet with higher intakes of energy, and animal derived foods (SATFAT and calcium) could have protected against the detrimental decreases in TC observed in HIV infection. Significant differences were observed in the intakes in the non-infected THUSA women who had serum albumin in the first and fourth quartiles. lntakes in percentage energy from protein and fat, animal protein, total fat, SATFAT, MUFAT, calcium, zinc, vitamin C and fat ratio, were significantly lower in the women with albumin levels in the first quartile. Significantly higher carbohydrate intakes were observed in the women who had serum albumin levels in the first quartile. In the Mangaung study, significant differences were seen in the intakes between infected women who had serum albumin levels in the first and fourth quartiles. lntakes of total energy, protein, fat, MUFAT, SATFAT, carbohydrate, magnesium, zinc, chromium, biotin, pantothenic acid and iodine were significantly lower in the infected women with serum albumin levels in the first quartile. In the non-infected women significantly lower intakes of calcium were observed in the group who had serum albumin levels in the first quartile compared to those who had serum albumin levels in the fourth quartile. These results also suggest that a more "westernized” diet was associated with higher albumin levels in HIV-infected women. CONCLUSION: It is well known that nutrition has an integral part to play in the care of people living with HIV/AIDS (PLWHA). Maintaining proper nutrition, weight and immune function is thought to delay disease progression, prolong the asymptomatic phase and improve survival. These analyses suggest that the "prudent" diet generally regarded as an optimal diet for prevention of non-communicable diseases, may not be the optimal diet for PLWHA. The overall analyses therefore suggest that a more "westernized" diet, higher in fat and protein could be more beneficial to asymptomatic HIV-infected women compared to that of a more "prudent" diet. As these studies were not primarily designed to investigate HIV and nutrition, the role of a higher energy, fat and animal protein intake ("western" diet) in asymptomatic HIV warrants urgent investigation. / Thesis (Ph.D. (Nutrition))--North-West University, Potchefstroom Campus, 2007.

The purpose of this study was to rationally design animal component free, chemically defined serum free media (ACF-CD-SFM) for MRC-5 and Vero cells while adhering to the Quality by Design guidelines. This was achieved by using the Modified Vero Serum Free Medium (MVSFM) as the basal formulation and supplementing it with various combinations of growth factors (LONG® EGF, LONG® R3 IGF-I, rTransferrin, bFGF, TGF-3 and PDGF-AA), lipids (linoleic acid, cholesterol, and dexamethasone), lipid precursors (ethanolamine and phosphoethanolamine) and vitamins (all-trans retinoic acid, -tocopherol and ascorbic acid). Media development was achieved by conducting a series of steps using different experimental methodologies with the end goal of satisfying the requirements of each cell line. MRC-5 and Vero cells were each cultured in specific media containing unique concentrations of supplements that were prepared according to the different statistical design methodologies. The original objective was to create a SFM, however due to the stringent nutritious requirements of anchorage dependent cell lines, only a reduction to 0.5% FBS was achieved. For MRC-5 cells, the one-factor-at-a-time (OFAT) generated the Prototype + 0.5% FBS medium. The Definitive Screening Design (DSD) gave rise to the Delta 1 + 0.5% FBS, which was the optimum medium formulation for MRC-5 cells as it had comparable cell yields to DMEM + 10 % FBS. This result was confirmed by the Genetic Algorithms-Hill Climbing (GA-HC) method. In the case of Vero cells, the OFAT and the DSD confirmed that MVSFM + 0.5 % FBS was the most optimal formulation. The morphology in both media for both cell lines was comparable to that in DMEM-10% FBS. It was concluded that the DSD method successfully achieved a reduction of the serum concentration from 10% to 0.5% FBS. / October 2017

It is a striking observation that tissue of patients invaded by the deep mycoses often lacks evidence of an inflammatory response. This lack of host response is often attributed to neutropenia secondary to chemotherapy. However, systematic studies do not support this simplistic explanation. However, invasive fungal lesions are characterized by abundant fungal functional amyloid, which in turn is bound by serum amyloid P component (SAP). We postulate that SAP is important in the local immune response in invasive fungal infections. The interaction between fungal functional amyloid, SAP, and the immune response in deep mycoses is discussed.

Compositions are vectors of nonnegative numbers that sum to a constant, usually one or 100%. They arise in a wide array of fields: geological sampling, budgets,fat/protein/carbohydrate in foods, percentage of the vote acquired by each political party, and more. The usual candidate distributions for modeling compositions -- the Dirichlet and the logistic normal distribution -- have density zero if any component is zero. While statistical methods have been developed for "rounded" zeros, zeros stemming from values below a detection level, and zeros arising from count data, there remain problems with essential zeros, i.e. cases in continuous compositions where a component is truly absent. We develop a model for compositions with essential zeros based on an approach by Aitchison and Kay (2003). It uses a mixture of additive logistic normal distributions of different dimension, related by common parameters. With the requirement of an additional constraint, we develop a likelihood and methods estimating parameters for location and dispersion. We also develop a permutation test for a two-group comparison, and demonstrate the model and test using data from a diabetes study. These results provide the first use of the additive logistic normal distribution formodeling and testing compositional data in the presence of essential zeros.

Doctor of Philosophy / Department of Chemistry / Stefan H. Bossmann / Numerous proteases are known to be necessary for cancer development and progression including Matrix Metalloproteinases (MMPs), Tissue Serine Proteases, and Cathepsins. The goal of this research is to develop a Fe/Fe₃O₄ nanoparticle-based system for clinical diagnostics, which has the potential to measure the activity of cancer-associated proteases in biospecimens. Our nanoparticle-based “light switches” for measuring protease activity, consist of fluorescent cyanine dyes which are directly attached to Fe/Fe₃O₄ nanoparticles and porphyrins that are attached to Fe/Fe₃O₄ nanoparticles via consensus sequences. The consensus (cleavage) sequences can be cleaved in the presence of the correct protease, thus releasing a fluorescent dye from the Fe/Fe₃O₄ nanoparticle resulting in highly sensitive (down to 1 x 10⁻¹⁶ mol L⁻¹ for 12 proteases), selective, and fast nanoplatforms (required time: 60 min.). Upon escape, the emission intensity of the organic dye will significantly increase, which can be detected using fluorescence spectroscopy. In order to demonstrate the potential of this new technology of early recognition of various cancers several analysis types have been used. Blood and urine samples from human cancer patients and healthy volunteers, tissue and blood serum samples from human cancer patients, and canine urine and blood serum samples are some of those types. Blood samples from human cancer patients and healthy volunteers were used to demonstrate the potential of this new technology for the early recognition of breast and lung cancers. We were able to establish several proteases with diagnostic potential for breast cancer and non-small cell lung cancer. It is very likely that different cancers will feature different “protease signatures”, meaning that different proteases will be activated, depending on the origin of cancer. This permits the diagnosis of various solid tumors at different stages. Tissue samples were collected from normal tissues, from the boundary of the tumor and from the tumor of the same person. Performed fluorescence experiments clearly indicate that tissue samples from the tumor show the highest fluorescence indicating the highest concentration of the protease. Results can be used excellently in a diagnostic system for breast cancer. Based on our results measuring protease signatures offers an inexpensive and fast approach towards early cancer diagnostics.

O objetivo deste trabalho foi analisar a influência dos fatores etários, sexuais, da gestação, do puerpério, da lactação e dos sistemas de criação nos constituintes do metabolismo lipídico e glicemia de búfalos. A análise bioquímica foi obtida por meio da determinação dos teores séricos de colesterol, triglicérides, ß-hidroxibutirato (ß-HBO), ácidos graxos não esterificados (NEFA), e teores plasmáticos de glicose. Também foi objetivo sugerir valores de referência para estes metabólitos. Foram utilizadas seis propriedades de bubalinos das raças Murrah, Mediterrâneo, e mestiços, todas localizadas no Estado de São Paulo. No total, foram colhidas amostras de soro e plasma de 635 animais, entre novembro de 2009 e julho de 2010. Para a avaliação da condição do estado geral dos animais, foi utilizada avaliação do escore de condição corporal (ECC) atribuindo notas de 1 a 5 somente para animais acima de 24 meses. Os valores da média aritmética, desvio padrão, erro padrão da média, coeficiente de variação, intervalo de confiança (95%), e valores mínimo e máximo foram calculados utilizando o procedimento Means do SAS versão 9.2. Os testes de normalidade dos resíduos e homogeneidade das variâncias foram realizados utilizando o Guide Data Analise do SAS. Os dados foram analisados por ANOVA, usando o procedimento Glimmix do SAS. As informações de grupo (Idade; Gestação; Lactação; Sexo; Puerpério; Sistema de Criação), Fazenda; Categoria; Número de Crias e ECC, assim como suas interações, foram utilizadas nos modelos estatísticos. Concluiu-se que os constituintes metabólicos foram consideravelmente influenciados pela idade, sexo, puerpério, lactação e sistema de criação, não sendo verificada influência relevante pela gestação de novilhas. Devido à grande quantidade de amostras estrategicamente colhidas, obtidas de diferentes realidades criatórias, também foi possível sugerir valores de referência para o lipidograma e glicemia de búfalos de diferentes idades, sexos, momentos gestacionais, fases do periparto e períodos de lactação. / The aim of this study was to analyze the influence of age, gender, pregnancy, puerperium, lactation and breeding systems in the constituents of lipid metabolism and glucose of buffaloes. The biochemical analysis was obtained by determining the levels of serum cholesterol, triglycerides, beta-hydroxybutyrate (ß-HBO), non-esterified fatty acids (NEFA) and plasma glucose levels. It was also meant to suggest reference values for these metabolites. Were used six properties of buffaloes Murrah, Mediterranean, and crossbreed, all located in the São Paulo state. Were collected 635 samples of serum and plasma between November 2009 and July 2010. To assess the condition of the general state of animals was used to evaluate body condition score (BCS) by assigning scores from 1 to 5 only for animals over 24 months. The values of the arithmetic mean, standard deviation, standard error means, coefficient of variation, confidence interval (95%), and minimum and maximum values were calculated using the Means procedure of SAS version 9.2. Tests for normality of residuals and homogeneity of variances were performed using the SAS Guide to Data Analysis. Data were analyzed by ANOVA using the SAS procedure Glimmix. The group information (Age, Pregnancy, Lactation, Gender, Puerperium; Creation System), Farm, Category, Number of Offspring and BCS, as well as their interactions, were used in statistical models. It was concluded that the metabolic components were significantly influenced by age, gender, postpartum, lactation and breeding system, and is not verified by the relevant influence pregnant heifers. Due to the large number of samples strategically taken, obtained from different stock breeding, were also suggest reference values for serum lipids and glucose of buffaloes in different ages, genders, moments of pregnancy, stages of peripartum and lactation periods.

Healthy articular joints exhibit remarkable lubrication due in large part to the complex rheological and tribological behavior of the synovial fluid (SF) that lubricates the joints. Current approaches that seek to elucidate such remarkable lubrication usually focus on the roles of high molecular weight SF components such as lubricin and hyaluronic acid but frequently overlook the role of serum albumin (SA), although it represents 90% of the protein content of SF. In this thesis, we used the Surface Forces Apparatus to investigate in detail the structural and tribological response of SA thin films when sheared between model surfaces and subjected to a large range of shearing parameters. Our data indicate that, under shear, SA films reproduce closely the shear response previously reported for SF, i.e., film thickening and formation of numerous long-lived aggregates accompanied by low friction and efficient surface protection against damage. More specifically, our detailed investigation of shear parameters reveals that (i) strong anchoring of SA to surfaces promotes the formation of large rod-like shaped aggregates that enable rolling friction and keep surfaces far apart, preventing damage, (ii) aggregation mechanism is irreversible, which makes aggregates long-lived (though mobile) in the contact, and (iii) aggregate formation only occur when SA was sheared above a ‘critical’ amplitude Ac and a critical shear velocity Vc. Collectively, our results provide experimental evidence of the role of globular proteins, such as SA, in lubrication and establish a correlation between shearing parameters, formation and stability of aggregates, low friction and wear protection. Although our findings are based on experiments involving rigid, nonporous surfaces hence can hardly be generalized to compliant and porous cartilage surfaces, they are applicable to other rigid tribosystems such as artificial joints and will certainly advance our understanding of joint implants’ lubrication in SF mediated by protein aggregation, with implications for future design of artificial joints and therapeutic interventions.

O soro anti-elapidico brasileiro é produzido com uma mistura de veneno de Micrurus frontalis e de M. corallinus. Estudos indicam que o soro resultante não neutraliza o veneno de algumas espécies de Micrurus. Além disso, o baixo rendimento de veneno e as dificuldades de manutenção destas serpentes em cativeiro dificultam a produção de soro. Assim, um método alternativo para a produção deste soro seria de grande valor. Estudos têm mostrado que os venenos de elapideos brasileiros contêm toxinas com um elevado grau de homologia com as de suas congêneres australianas. O presente trabalho teve como objetivo comparar inicialmente o soro brasileiro e o australiano frente ao veneno de Micrurus frontalis e M. lemniscatus. A reatividade cruzada foi testada por Western-blot e ELISA com veneno de Micrurus frontalis e a capacidade neutralizante por soroneutralização com venenos de M. frontalis, M. lemniscatus, e em parceiria com venenos de M. corallinus, M. altirostris, M. spixii, M. ibiboboca, M. fulvius, M. pyrrhocryptus , M. nigrocinctus, em camundongos. Os dados obtidos indicam nível elevado de reatividade e neutralização cruzada entre os soros. Também comparamos a imunogenicidade do veneno nativo ou irradiado, não observando diferenças nos níveis de anticorpos obtidos. As serpentes australianas utilizadas para a produção de soro são mais fáceis de manusear e produzem maiores quantidades de venenos do que as corais brasileiras. Concluímos que um soro produzido com o veneno de serpentes australianas neutraliza a atividade tóxica das Micrurus estudadas, incluindo espécies que o soro nacional não neutraliza. Assim, o uso de venenos da Austrália como imunógeno constitui alternativa viável para sanar a carência do soro nacional. / The Brazilian coral snake antivenom is produced using a mixture of Micrurus corallinus and M. frontalis venom. Several studies have shown that this serum does not neutralize the venom of some species. Furthermore, the low venom yields and the difficulties of keeping coral snakes in captivity impair antivenom production. Althought belonging to different species, coral snakes and Australian elapids share many homologous toxins in their venom. The present work aimed to compare the Brazilian and Australian antivenoms against Micrurus venom. Cross- reactivity was assayed by Western blot and ELISA, while cross-neutralization was tested in mice. Both tipes of assays indicate high levels of cross-reactivity and neutralization. We also tested the immunogenicity of native or radiation-attenuated venom and no significant difference in antibody levels was observed. The Australian snakes used for antivenom production are much easier to breed and produce higher amounts of venom that their Brazilian relatives. From this study, we conclude that a serum produced using Australian venoms neutralizes the toxicity of coral snakes venoms, including several venoms which are not neutralized by the Brazilian antivenom. Thus, the use of Australian venoms as an immunogen might solve the bottleneck of coral snake antivenom production.

One-dimensional nanostructures have offered unique advantages in many fields. Protein based nanotubes, in particular, are desirable for biomedical applications due to their ease of functionlization and intrinsic biocompatibility. Template-assisted methods are widely used to fabricate cylindrical nanostructures like carbon nanotubes, metal nanowires, polymer nanorods, etc. In the fabrication of protein nanostructures, the layer by layer (LbL) technique has long been applied to deposit protein multilayers on planar and spherical substrates. The success in each area led to the conclusion that the combination of these two techniques will potentially bring us the capability of fabricating protein nanotubes in a more controllable fashion. In this work, protein nanotubes have been successfully deposited inside nanoscopic pores by sequential filtration of bovine serum albumin (BSA) solution at pH 3.8 and pH 7.0 through the channels in the anodic aluminum oxide (AAO) template. The morphologies of the obtained nanostructures have been examined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Also, a simple analysis from UV/Vis spectroscopy has shown that the solutions used in our experiment will not significantly damage the bioactivity of BSA. Our future work will focus on strengthening the mechanical stability of the protein nanotubes and controlling their morphology more precisely.