Background: The role of dietary calcium in weight management is gaining support in the nutrition research community. It has been hypothesized that high calcium diets protect against fat gain by creating a balance of lipolysis over lipogenesis in adipocytes (Zemel et al., 2000) and that a diet deficient in calcium is associated with higher body weight and that augmenting calcium intake may reduce weight and fat gain or enhance fat loss (Shapses et al., 2004). Objectives: A lack of baseline data on the physical, physiological and mental effects of obesity on urban African women was the motivation for the POWIRS (Profiles of Obese Women with Insulin Resistance Syndrome) study. The aim of the study was to assess the effects of obesity on health determinants of urban African and white women by comparing the lifestyle and risk factors for non-communicable diseases (NCDs) of lean, overweight and obese subjects. This led to a multi-disciplinary cross-sectional case-control study in which health determinants and health status, as well as the underlying mechanistic relationships between these factors were measured in a sample of African women volunteers. The study was repeated a year later, done in a sample of white women volunteers, POWIRS II. The effect of calcium intake on body composition was assessed during this study. Methods: One hundred and two apparently healthy urban African women, between the ages of 20 and 50 years participated in the first phase of this case-control cross-sectional survey. For a period of about three weeks, each afternoon ten subjects were to report at a Metabolic Unit Facility (consisting of 10 single bedrooms, 2 bathrooms, a living room and kitchen). Each subject received a "participant sheet" which guided them through the different research 'stations' where the various measurements were done. During the course of the evening demographic questionnaires were filled in and all anthropometric measurements were taken, except weight and height measurements. All participants received an identical light supper which excluded alcohol and caffeine at 20h00, went to sleep before 23h00 and fasted overnight. From 06h00 in the morning weight, height and blood pressure measurements were taken. After a fasting blood sample was taken, a two-hour glucose tolerance test commenced. Subjects received a breakfast and afterwards habitual dietary intake questionnaires were completed. Results: Mean total dietary calcium intake as significantly higher in white women (POWIRS II), with a mean intake 1053.8 mg per day, as opposed to a mean intake of 494.8 mg calcium per day in the blacks subjects (POWIRS I). Mean fat intake in the black subjects was 59.3 g per day, and in the white women 103.1 g per day. Thus the calcium:fat ratio in white women was higher than in black women (11.0 and 8.4 respectively). After adjustment for age and total dietary energy intake, significant negative correlations were found between dietary calcium intake and various variables, only in the white subjects. These were BMI (r=-0.255, p=0.01), percentage body fat (r=-0.252, p=0.01), fasting insulin (r=-0.205, p=0.05) and fasting glucose (r=-0.199, p=0.046). The calcium:fat ratio correlated negatively with BMI (r=-0.378, p<0.0001), percentage body fat (r=-0.401, p<0.0001), fasting glucose (r=-0.229, p=0.02), fasting insulin (r=-0.212, p=0.04) and plasma leptin (r=-0.284, p=0.004). Adjustment for smoking resulted in slightly different correlation coefficients, but similar significant correlations were still found. The only significant association that was found in the black population, was a negative correlation between dietary calcium intake and systolic blood pressure (p=0.03) as well as diastolic blood pressure (p=0.04). After adjustment for age, smoking and dietary energy intake no significant correlations were found in the black subjects. Conclusion: The results from the POWIRS study in white women are consistent with the hypothesis that there may be an inverse relationship between adiposity and calcium intake. In our study higher calcium intakes were associated with lower body fat, lower BMI, lower fasting glucose and insulin, as well as plasma leptin in white women. The association seems to be significant in subjects with high intakes of fat and calcium (as seen in the white women). / Thesis (M.Sc. (Dietetics))--North-West University, Potchefstroom Campus, 2005.

Leptin is a protein hormone primarily secreted by the subcutaneous adipose tissue and is responsible for regulating the energy balance. Individuals with more adipose tissue have much higher leptin levels and often suffer from a condition known as leptin resistance. Various factors such as gender, age, ethnicity, diet and physical activity influence the body's leptin concentration. Males have lower leptin levels than females of the same age and body fat content. Black people tend to have higher leptin concentrations than white people because of a more subcutaneous adipose tissue distribution. Physical activity serve as a main manipulator of the body's energy balance and influence leptin concentration through various adaptations associated with a more favorable body composition such as, an increase in lean tissue and a decrease in body fat. The object of this study was firstly to investigate the association between body composition - with special emphasis on adipose tissue and leptin concentration in black adolescent boys and girls of the North-West Province of South Africa. Secondly, the study aimed to determine the influence of physical fitness components and leptin concentration in the same population. In this study, 148 girls and 114 boys supplied overnight fasting blood samples. Anthropometric data: length (m), weight (kg), skin folds (mm) and circumferences of the waist (cm) and hip (cm) were measured. The percentage body fat were also measured in the BOD-POD. Finally a battery of physical fitness tests were done which included: the maximum number of sit-ups, push-ups and the bleep-test for indirect V&-max. Spearman Rank Order correlations determined that there should be adjusted for age and Tanner stage. Partial correlations were done with body composition variables, [BMI (body mass index), SSF (sum of 6 skin folds), body fat percentage], and physical fitness variables, bush-ups, sit-ups and indirect V02-max]. In both genders a strong positive relationship occurred between all the above mentioned body composition variables and leptin. In boys the strongest correlation (I= 0.8420) was found between SSF and leptin levels. In girls the strongest correlation (r = 0.7489) was found between BMI and leptin concentration. In both genders, body fat percentage indicated the lowest correlation, although it was still significant. In both genders the indirect V02-max values indicated a significant negative relationship with serum leptin concentration, although it was weak, it was the highest in boys (r = - 0314). In girls the indirect V02-max values (r = -0.235) and the maximum amount of push-ups (r = -0205) indicated significant, but weak correlations. According to the results of this study it is clear that serum leptin concentration has a strong positive relationship with body fat, more accurate, with the subcutaneous adipose tissue. It was also indicated that baseline physical fitness in these black adolescents from the selected school in Potchefstroom, North-west Province (South Africa) are statistically significant negatively correlated with leptin levels, although it was not a strong correlation. / Thesis (M.Sc. (Human Movement Science))--North-West University, Potchefstroom Campus, 2006.

This thesis consists of a brief description on cancer, carcinogenesis, the changes in the type and level of dietary fat available in our diets over time and association with the development of certain diseases. The main focus of this research was on omega 6 and omega 3 essential fatty acids (EFA) and their interaction with regards to carcinogenesis.

Video files: Some images may require stereoscopic glasses / Fat in milk and cream is present as tiny droplets, which are each enveloped in a thin membrane, called the milk fat globule membrane (MFGM). The MFGM can easily be damaged by factors such as pumping the milk and applying other forms of agitation. MFGM damage is believed to reduce processing efficiency and compromise the quality of manufactured products. A comprehensive review of the literature showed that our understanding of changes occurring in the MFGM post secretion of the fat globule by the mammary secretory cell is still rudimentary. Furthermore, it was found that a fundamental understanding of MFGM damage in raw milk is lacking. Hence, this study sought to develop analytical techniques for studying the MFGM. Fluorescent probes were identified that associated with the MFGM (bovine, ovine, human) in one of two ways: either by embedding in the phospholipid bilayer (lipophilic probe) or by binding to carbohydrate moieties of glycosylated chains in the glycocalyx (lectin probes). The use of these probes, in combination with either conventional fluorescence microscopy or confocal laser scanning microscopy, allowed 2-D images and 3-D images of fat globules to be made. Application of water-soluble lipophilic probes and the lectin wheat germ agglutinin (WGA) directly to milk allowed the staining of the MFGM in its native environment. Variable distribution patterns of the probes in the MFGM were observed, which suggests that the MFGM of fat globules in harvested milk is structurally and chemically heterogeneous both within and among globules from the same species and between species, and even among fat globules within the milk of an individual animal. Furthermore, the binding behaviour of WGA to the MFGM of native fat globules (in bovine milk) and washed fat globules (in model systems) following heat treatment implicated β-lactoglobulin, α-lactalbumin, immunoglobulin M and/or the glycosylated proteins Periodic acid Schiff 6/7 in the disappearance of fat globule aggregation upon elevated heat treatment of milk. The results of the current study showed that the use of membrane-specific fluorescent probes, particularly in combination with confocal laser scanning microscopy, has significant potential for providing real time structural and chemical information about the MFGM in matrices such as harvested milk and milk products. In addition to the fluorescence microscopy techniques, development of other techniques was also conducted. Flow cytometry was shown to have significant potential for the quantitative determination of various properties of fat globules and their membranes. Although no suitable sample preparation technique could be developed in this study, atomic force microscopy is believed to have significant potential for studying structural and physical properties of the MFGM. Selective harvesting of individual fat globules was shown to be possible by using a micromanipulator. In future work, this technique is expected to be used in combination with fluorescence microscopy, or atomic force microscopy. The present study has shown that the development and application of novel analytical techniques has advanced, and in the future will further advance, understanding of the MFGM.

Introdução: A medida do percentual de gordura corporal (PGC) sofre a influência de diversos fatores (obesidade severa, acúmulo excessivo de gordura no abdomen, hidratação, etc), dependendo da técnica utilizada, podendo comprometer o desempenho das mesmas. Muitos destes fatores estão frequentemente presentes nos pacientes com DM tipo 2, o que torna essencial o estudo da acurácia destes métodos nesta população. Objetivo: Avaliar a Bioimpedância (BIA) e as Dobras Cutâneas (DC) como métodos de estimativa da gordura corporal em pacientes com DM tipo 2, comparando-os com a Absorciometria de Raios X de Dupla Energia (DXA), como método de referência. Métodos: Neste estudo de acurácia diagnóstica, os pacientes foram submetidos à avaliação da composição corporal através da BIA (InBody 230, Biospace, Coréia), das DC (Lange, Fórmulas de Petroski e de Durnin) e da DXA (Lunar - iDXA). Para avaliação clínica foram analisados o controle metabólico (glicêmico e perfil lipídico) e pressórico e pesquisadas as complicações crônicas do DM. Resultados. Foram avaliados 133 pacientes (76 mulheres; idade: 63,6 ± 9,1 anos, duração do DM: 15,5 ± 10,3 anos; IMC: 29,2 ± 3,6), sendo que o PGC médio foi de 42,4 ± 4,8% nas mulheres e 31,1 ± 4,7% nos homens (p<0,001). A correlação do PGC estimado pela BIA e pelas DC com o estimado pela DXA foi, respectivamente r=0,93 (p<0,001) e r=0,81 (p<0,001). A BIA subestimou o PGC em 1,4 ± 3,2 (p<0,05) nas mulheres e 2,3 ± 3,3% (p<0,05) nos homens, quando comparada a DXA, sendo estas diferenças menos acentuadas nos pacientes com IMC≥ 30 kg/m2 (Gráficos de Bland-Altman). As DC subestimaram o PGC quando calculado com a Fórmula de Petroski, (3,7 ± 4,0% [p<0,05] nas mulheres e 1,55 ± 3,8% [p<0,05] nos homens) e superestimaram quando calculado com a Fórmula de Durnin ajustada para a idade, sendo que este ultimo apenas nas mulheres (1,8 ± 4,5% [p<0,05]). Na análise das curvas ROC, a área sob a curva da BIA foi 0,945 nas mulheres e 0,897 nos homens. Para as DC, utilizando as diferentes fórmulas, as áreas sob a curva variaram de 0,611 a 0,673 nas mulheres e foram 0,960 nos homens. Conclusão: Para a avaliação da composição corporal de pacientes com DM tipo 2, tanto a BIA como as DC (dependendo da fórmula) subestimam o PGC, comparados a DXA, mas em valores não clinicamente relevantes. A BIA apresentou uma boa acurácia em ambos sexos. Já a medida pelas DC mostrou acurácia semelhante, mas apenas nos homens. / Objective. To evaluate the performance of bioimpedance (BIA) and skinfold thickness as methods to estimate percentage body fat (PBF) in patients with Type 2 diabetes, comparing them to Dual Energy X-Ray Absorptiometry (DXA), as a reference standard. Research Design and Methods. In this study of diagnostic accuracy, the patients were submitted to evaluation of body composition with BIA (InBody 230, Biospace, Korea), skinfold thickness (Lange caliper) and DXA (Lunar - iDXA). PBF estimated by skinfold thickness was calculated with three equations: Petroski, Durnin & Womersley (DW) gender-adjusted and DW age-adjusted. Clinical evaluation consisted of the metabolic (glycemic and lipid profile) and blood pressure control, as well as the search for diabetic chronic complications. Results. One hundred and thirty-three patients were evaluated (76 women; age: 63.6 ± 9.1 years, duration of diabetes: 15.5 ± 10.3 years; body mass index [BMI]: 29.2 ± 3.6 kg/m2). PBF estimated by DXA was 42.4 ± 4.8% in women and 31.1 ± 4.7% in men (p<0.001). The correlation of the PBF estimated by BIA and by skinfold thickness with that estimated by DXA was, respectively, 0.93 (p<0.001) and 0.81 (p<0.001). BIA underestimated the PBF at 1.4 ± 3.2 (p<0.05) in women and 2.3 ± 3.3% (p<0.05) in men, compared to DXA, and these differences were less pronounced in patients with BMI ≥ 30 kg/m2 (Bland-Altman Plots). PBF calculated by Petroski’s equations was underestimated in 3.7 ± 4.0% [p<0,05] in women and 1.55 ± 3.8% [p<0.05] in men; and overestimated in 1.8 ± 4.5% [p<0.05] when calculated using DW equations age-adjusted only in women. The area under the ROC curves for BIA as a method to identify patients with increased PBF was 0.945 (p<0.001) in women and 0.897 (p<0.001) in men. The area under the ROC curves for skinfold thickness varied from 0.611 to 0.673 (all p>0.05) in women and was 0.960 (all P<0,05) in men. Conclusion. In patients with type 2 diabetes, both BIA and skinfold thickness underestimated PBF, when compared to DXA, at values that ranged from 1.4 to 2.3% and 1.5 to 4.5%, respectively. BIA was accurate in both sexes as a method to estimate PBF and to identify patients with increased PBF. On the other hand, PBF estimated by skinfold thickness was similarly accurate, but only in males.

Rabies is an infectious disease of the central nervous system caused by the rabies virus (RABV), which affects all mammals. In Brazil the rabies has caused considerable losses to cattle herds in various regions. The official diagnosis is made by the fluorescent antibody technique (FAT) concomitantly with biological assay, usually the mouse inoculation tests (MIT). The MIT is considered a sensitive, specific and effective technique for rabies diagnosis, but has disadvantages such as long time to obtain the results and the need to use animals. The first paper of this dissertation describes a molecular and epidemiological investigation of outbreaks of bovine rabies occurring in the central region of Rio Grande do Sul state, Brazil, between May and August 2012. In this period, 45 cases suspected of rabies were reported in 22 small herds, located within a 4.7km range, in the county of Pinhal Grande. From these, 32 samples were submitted to rabies diagnosis and RabV and/or viral antigens were identified in 27 samples. Subsequently, 11 brain samples were submitted to reverse transcription/polymerase chain reaction (RT-PCR) for the nucleoprotein gene (N) followed by nucleotide sequencing and phylogenetic analysis. Seven out of 11 samples yielded identical sequences; one presented a synonymous, non-coding mutation, indicating a likely common origin of the virus. However, three other samples presented nucleotide mutations which resulted in amino acid changes, suggesting a different origin of the virus. In summary, these results suggest that RabV strains of different origin/lineages co-circulate in the region and were involved in the outbreaks. The second paper describes an evaluation of sensitivity for VI of Rabv in neuroblastoma cells (N2A) and baby hamster kidney cells (BHK-21). For this, thirty-six samples derived bovine brains of suspected rabies cases were initially submitted to the FAT and MIT test and subsequently to three protocols VI in each cell line: a single pass 24h and 72h, and three passes 48h. The average time to obtain final results at MIT was 12.3 days (8-21). The average time required for final MIT results was 12.3 days (8 21). The FAT and MIT combined detected 32/36 positive samples, these MIT detected 32 (100%) and the FAT detected 31 (96.8%). The isolation in BHK-21 cells resulted in 100% (32/32) positivity in the protocol of 72h and 96.9% (31/32) after three passages of 48h. The isolation in N2A cells resulted in 100% (32/32) positive for 72h and 30/32 (93.7%) samples 48h after three passages. A single 24h passage protocol (T1) in both cell lines performed poorly, detecting less than 40% of the positive samples. These results indicate that VI in either cell line, especially in BHK-21 cells that grow faster and are much easier to maintain than N2A cells, does represent an adequate alternative for MIT as a confirmatory test for rabies diagnostic in bovine specimens, yielding reliable results in reduced time. / A raiva é uma doença infecciosa do sistema nervoso central causada pelo vírus da raiva (RabV), que afeta todos os mamíferos. No Brasil a raiva tem causado consideráveis perdas a rebanhos bovinos em diversas regiões. O diagnóstico oficial é realizado pela técnica de imunofluorescência direta (FAT) de forma concomitante com a prova biológica, geralmente a inoculação intracerebral em camundongos (MIT). A MIT é considerada uma técnica sensível, específica e eficaz para o diagnóstico da raiva, porém apresenta desvantagens como o longo tempo para obtenção dos resultados e a necessidade de uso de animais. O primeiro artigo da presente dissertação descreve uma investigação epidemiológica e molecular de surtos de raiva ocorridos na região central do Rio Grande do Sul, entre maio e agosto de 2012. Nesse período, 45 casos suspeitos de raiva foram relatados em 22 rebanhos, localizados dentro de um raio de 4,7km, no município de Pinhal Grande. Desses, 32 amostras foram submetidas para diagnóstico da raiva, sendo que o RabV e/ou antígenos virais foram identificados em 27 amostras. Em um segundo momento, 11 amostras foram submetidas à transcrição reversa - - reação em cadeia da polimerase (RT-PCR) para o gene da nucleoproteína (N) do RabV, seguido de sequenciamento nucleotídico e análise filogenética. Sete das 11 amostras apresentaram sequências nucleotídicas idênticas e uma apresentou mutação sinônima, não-codificante, indicando uma provável origem comum dos vírus. Por outro lado, três amostras apresentaram mutações que resultaram em alterações de aminoácidos, sugerindo uma origem diferente do vírus. Esses resultados sugerem que RabV de diferentes origens/linhagens co-circulam na região e foram envolvidos nos surtos descritos. O segundo artigo descreve a avaliação da sensibilidade ao isolamento do RabV em linhagens de células de neuroblastoma murino (N2A) e rim de hamster neonato (BHK-21). Para isso, trinta e seis amostras de cérebros bovinos oriundos de casos suspeitos de raiva foram inicialmente submetidas ao teste de FAT e MIT e, subsequentemente, a três protocolos de VI em cada linhagem celular: uma única passagem de 24h e 72h, e três passagens de 48h. O tempo médio necessário para obtenção de resultados finais na MIT foi de 12,3 dias (8-21). A FAT e MIT combinadas detectaram 32/36 amostras positivas. Dessas, a MIT detectou 32 (100%) e a FAT detectou 31 (96,8%). O tempo médio necessário para obter os resultados conclusivos na MIT foi de 12,3 dias (8-21). O isolamento em células BHK-21 resultou em 100% (32/32) de positividade no protocolo de 72h e em 96,9% (31/32) após três passagens de 48h. Em células N2A o isolamento resultou em 100% (32/32) das amostras positivas em 72h e em 30/32 (93,7%) após três passagens de 48h. Uma única passagem de 24h em ambas as linhagens mostrou um baixo desempenho, detectando menos de 40% das amostras positivas. Estes resultados indicam que o isolamento viral em qualquer uma das linhagens representa uma boa alternativa para a MIT como um teste confirmatório para o diagnóstico da raiva em amostras de bovinos, produzindo resultados confiáveis em tempo reduzido.

Media har en stor påverkan på samhällets kroppsideal då många strävar efter en idealisk kropp. På sociala medier är termer som body positivity och body shaming aktuella, därför har vi använt oss av dessa termer för att fördjupa oss i studien. Syftet med studien är att framhäva konsekvenserna av att bli body shamed, både fysiskt och psykiskt. Body positivity är ett positivt laddat ord då syftet är att man skall acceptera sig själv och inte påverkas av de ytliga normer samhället och media konstruerat. Body shaming är ett negativt laddat begrepp på sociala medier som påverkar många människor negativt mentalt då man utsätts för kränkningar på grund av sitt kroppsliga utseende. Youtube är ett stort nätverk där människor kan ta del av andras vardag och åsikter, som forskningsläge har vi valt att fokusera oss på youtubers och deras videos om kroppsideal. Vi analyserar kommentarer på videos för att komma fram till ett större urval om hur dessa ämnen påverkar individer.

Introdução: A medida do percentual de gordura corporal (PGC) sofre a influência de diversos fatores (obesidade severa, acúmulo excessivo de gordura no abdomen, hidratação, etc), dependendo da técnica utilizada, podendo comprometer o desempenho das mesmas. Muitos destes fatores estão frequentemente presentes nos pacientes com DM tipo 2, o que torna essencial o estudo da acurácia destes métodos nesta população. Objetivo: Avaliar a Bioimpedância (BIA) e as Dobras Cutâneas (DC) como métodos de estimativa da gordura corporal em pacientes com DM tipo 2, comparando-os com a Absorciometria de Raios X de Dupla Energia (DXA), como método de referência. Métodos: Neste estudo de acurácia diagnóstica, os pacientes foram submetidos à avaliação da composição corporal através da BIA (InBody 230, Biospace, Coréia), das DC (Lange, Fórmulas de Petroski e de Durnin) e da DXA (Lunar - iDXA). Para avaliação clínica foram analisados o controle metabólico (glicêmico e perfil lipídico) e pressórico e pesquisadas as complicações crônicas do DM. Resultados. Foram avaliados 133 pacientes (76 mulheres; idade: 63,6 ± 9,1 anos, duração do DM: 15,5 ± 10,3 anos; IMC: 29,2 ± 3,6), sendo que o PGC médio foi de 42,4 ± 4,8% nas mulheres e 31,1 ± 4,7% nos homens (p<0,001). A correlação do PGC estimado pela BIA e pelas DC com o estimado pela DXA foi, respectivamente r=0,93 (p<0,001) e r=0,81 (p<0,001). A BIA subestimou o PGC em 1,4 ± 3,2 (p<0,05) nas mulheres e 2,3 ± 3,3% (p<0,05) nos homens, quando comparada a DXA, sendo estas diferenças menos acentuadas nos pacientes com IMC≥ 30 kg/m2 (Gráficos de Bland-Altman). As DC subestimaram o PGC quando calculado com a Fórmula de Petroski, (3,7 ± 4,0% [p<0,05] nas mulheres e 1,55 ± 3,8% [p<0,05] nos homens) e superestimaram quando calculado com a Fórmula de Durnin ajustada para a idade, sendo que este ultimo apenas nas mulheres (1,8 ± 4,5% [p<0,05]). Na análise das curvas ROC, a área sob a curva da BIA foi 0,945 nas mulheres e 0,897 nos homens. Para as DC, utilizando as diferentes fórmulas, as áreas sob a curva variaram de 0,611 a 0,673 nas mulheres e foram 0,960 nos homens. Conclusão: Para a avaliação da composição corporal de pacientes com DM tipo 2, tanto a BIA como as DC (dependendo da fórmula) subestimam o PGC, comparados a DXA, mas em valores não clinicamente relevantes. A BIA apresentou uma boa acurácia em ambos sexos. Já a medida pelas DC mostrou acurácia semelhante, mas apenas nos homens. / Objective. To evaluate the performance of bioimpedance (BIA) and skinfold thickness as methods to estimate percentage body fat (PBF) in patients with Type 2 diabetes, comparing them to Dual Energy X-Ray Absorptiometry (DXA), as a reference standard. Research Design and Methods. In this study of diagnostic accuracy, the patients were submitted to evaluation of body composition with BIA (InBody 230, Biospace, Korea), skinfold thickness (Lange caliper) and DXA (Lunar - iDXA). PBF estimated by skinfold thickness was calculated with three equations: Petroski, Durnin & Womersley (DW) gender-adjusted and DW age-adjusted. Clinical evaluation consisted of the metabolic (glycemic and lipid profile) and blood pressure control, as well as the search for diabetic chronic complications. Results. One hundred and thirty-three patients were evaluated (76 women; age: 63.6 ± 9.1 years, duration of diabetes: 15.5 ± 10.3 years; body mass index [BMI]: 29.2 ± 3.6 kg/m2). PBF estimated by DXA was 42.4 ± 4.8% in women and 31.1 ± 4.7% in men (p<0.001). The correlation of the PBF estimated by BIA and by skinfold thickness with that estimated by DXA was, respectively, 0.93 (p<0.001) and 0.81 (p<0.001). BIA underestimated the PBF at 1.4 ± 3.2 (p<0.05) in women and 2.3 ± 3.3% (p<0.05) in men, compared to DXA, and these differences were less pronounced in patients with BMI ≥ 30 kg/m2 (Bland-Altman Plots). PBF calculated by Petroski’s equations was underestimated in 3.7 ± 4.0% [p<0,05] in women and 1.55 ± 3.8% [p<0.05] in men; and overestimated in 1.8 ± 4.5% [p<0.05] when calculated using DW equations age-adjusted only in women. The area under the ROC curves for BIA as a method to identify patients with increased PBF was 0.945 (p<0.001) in women and 0.897 (p<0.001) in men. The area under the ROC curves for skinfold thickness varied from 0.611 to 0.673 (all p>0.05) in women and was 0.960 (all P<0,05) in men. Conclusion. In patients with type 2 diabetes, both BIA and skinfold thickness underestimated PBF, when compared to DXA, at values that ranged from 1.4 to 2.3% and 1.5 to 4.5%, respectively. BIA was accurate in both sexes as a method to estimate PBF and to identify patients with increased PBF. On the other hand, PBF estimated by skinfold thickness was similarly accurate, but only in males.

Introdução: A medida do percentual de gordura corporal (PGC) sofre a influência de diversos fatores (obesidade severa, acúmulo excessivo de gordura no abdomen, hidratação, etc), dependendo da técnica utilizada, podendo comprometer o desempenho das mesmas. Muitos destes fatores estão frequentemente presentes nos pacientes com DM tipo 2, o que torna essencial o estudo da acurácia destes métodos nesta população. Objetivo: Avaliar a Bioimpedância (BIA) e as Dobras Cutâneas (DC) como métodos de estimativa da gordura corporal em pacientes com DM tipo 2, comparando-os com a Absorciometria de Raios X de Dupla Energia (DXA), como método de referência. Métodos: Neste estudo de acurácia diagnóstica, os pacientes foram submetidos à avaliação da composição corporal através da BIA (InBody 230, Biospace, Coréia), das DC (Lange, Fórmulas de Petroski e de Durnin) e da DXA (Lunar - iDXA). Para avaliação clínica foram analisados o controle metabólico (glicêmico e perfil lipídico) e pressórico e pesquisadas as complicações crônicas do DM. Resultados. Foram avaliados 133 pacientes (76 mulheres; idade: 63,6 ± 9,1 anos, duração do DM: 15,5 ± 10,3 anos; IMC: 29,2 ± 3,6), sendo que o PGC médio foi de 42,4 ± 4,8% nas mulheres e 31,1 ± 4,7% nos homens (p<0,001). A correlação do PGC estimado pela BIA e pelas DC com o estimado pela DXA foi, respectivamente r=0,93 (p<0,001) e r=0,81 (p<0,001). A BIA subestimou o PGC em 1,4 ± 3,2 (p<0,05) nas mulheres e 2,3 ± 3,3% (p<0,05) nos homens, quando comparada a DXA, sendo estas diferenças menos acentuadas nos pacientes com IMC≥ 30 kg/m2 (Gráficos de Bland-Altman). As DC subestimaram o PGC quando calculado com a Fórmula de Petroski, (3,7 ± 4,0% [p<0,05] nas mulheres e 1,55 ± 3,8% [p<0,05] nos homens) e superestimaram quando calculado com a Fórmula de Durnin ajustada para a idade, sendo que este ultimo apenas nas mulheres (1,8 ± 4,5% [p<0,05]). Na análise das curvas ROC, a área sob a curva da BIA foi 0,945 nas mulheres e 0,897 nos homens. Para as DC, utilizando as diferentes fórmulas, as áreas sob a curva variaram de 0,611 a 0,673 nas mulheres e foram 0,960 nos homens. Conclusão: Para a avaliação da composição corporal de pacientes com DM tipo 2, tanto a BIA como as DC (dependendo da fórmula) subestimam o PGC, comparados a DXA, mas em valores não clinicamente relevantes. A BIA apresentou uma boa acurácia em ambos sexos. Já a medida pelas DC mostrou acurácia semelhante, mas apenas nos homens. / Objective. To evaluate the performance of bioimpedance (BIA) and skinfold thickness as methods to estimate percentage body fat (PBF) in patients with Type 2 diabetes, comparing them to Dual Energy X-Ray Absorptiometry (DXA), as a reference standard. Research Design and Methods. In this study of diagnostic accuracy, the patients were submitted to evaluation of body composition with BIA (InBody 230, Biospace, Korea), skinfold thickness (Lange caliper) and DXA (Lunar - iDXA). PBF estimated by skinfold thickness was calculated with three equations: Petroski, Durnin & Womersley (DW) gender-adjusted and DW age-adjusted. Clinical evaluation consisted of the metabolic (glycemic and lipid profile) and blood pressure control, as well as the search for diabetic chronic complications. Results. One hundred and thirty-three patients were evaluated (76 women; age: 63.6 ± 9.1 years, duration of diabetes: 15.5 ± 10.3 years; body mass index [BMI]: 29.2 ± 3.6 kg/m2). PBF estimated by DXA was 42.4 ± 4.8% in women and 31.1 ± 4.7% in men (p<0.001). The correlation of the PBF estimated by BIA and by skinfold thickness with that estimated by DXA was, respectively, 0.93 (p<0.001) and 0.81 (p<0.001). BIA underestimated the PBF at 1.4 ± 3.2 (p<0.05) in women and 2.3 ± 3.3% (p<0.05) in men, compared to DXA, and these differences were less pronounced in patients with BMI ≥ 30 kg/m2 (Bland-Altman Plots). PBF calculated by Petroski’s equations was underestimated in 3.7 ± 4.0% [p<0,05] in women and 1.55 ± 3.8% [p<0.05] in men; and overestimated in 1.8 ± 4.5% [p<0.05] when calculated using DW equations age-adjusted only in women. The area under the ROC curves for BIA as a method to identify patients with increased PBF was 0.945 (p<0.001) in women and 0.897 (p<0.001) in men. The area under the ROC curves for skinfold thickness varied from 0.611 to 0.673 (all p>0.05) in women and was 0.960 (all P<0,05) in men. Conclusion. In patients with type 2 diabetes, both BIA and skinfold thickness underestimated PBF, when compared to DXA, at values that ranged from 1.4 to 2.3% and 1.5 to 4.5%, respectively. BIA was accurate in both sexes as a method to estimate PBF and to identify patients with increased PBF. On the other hand, PBF estimated by skinfold thickness was similarly accurate, but only in males.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-08-05T13:04:39Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese_Final_versão_biblioteca (2).pdf: 8187833 bytes, checksum: e76d125aa3b04c57265a2a3a15aca042 (MD5) / Made available in DSpace on 2016-08-05T13:04:39Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese_Final_versão_biblioteca (2).pdf: 8187833 bytes, checksum: e76d125aa3b04c57265a2a3a15aca042 (MD5) Previous issue date: 2016-02-24 / Introdução: Os tecidos adiposos subcutâneo (TAS) e, sobretudo, o visceral (TAV), quando em excesso, predizem riscos cardiometabólicos. Os métodos de quantificação do TAV e do TAS têm uso limitado na prática clínica sendo necessário identificar um marcador de alta validade para estimar a adiposidade visceral, que seja simples e de baixo custo. A circunferência abdominal (CA) é uma medida comumente empregada como proxy do TAV. No entanto, existe uma grande variação de protocolos para sua obtenção, comprometendo seu uso e comparação de resultados. Objetivos: Estimar a concentração de TAV e TAS e os fatores associados; estimar o grau de variabilidade da CA em diferentes sítios anatômicos e comparar a performance dos locais de medição como preditores de TAV, TAS e anormalidades cardiometabólicas; desenvolver um modelo preditivo para estimar o volume de TAV, a partir de idade e parâmetros antropométricos factíveis de serem utilizados na prática clínica; avaliar o efeito da perda de peso no TAV e TAS, e os efeitos da redução do TAV no perfil cardiometabólico. Métodos: Foram desenvolvidos dois delineamentos: um corte transversal para avaliar os fatores associados à concentração de TAV e TAS e aspectos metodológicos na estimativa do TAV; e uma intervenção clínica para verificar o efeito da restrição calórica no TAV, após um período de 3 meses, envolvendo adultos com excesso de peso, atendidos em hospital no Nordeste brasileiro. O TAV e TAS foram quantificados por tomografia computadorizada. A CA foi avaliada em seis sítios de medição. Outros parâmetros antropométricos avaliados foram: Índice de Massa Corpórea (IMC), Razão Cintura Quadril, Razão Cintura-Estatura, Diâmetro Sagital, Índice Sagital, Índice de Conicidade, Circunferência do Pescoço, Razão Pescoço-Coxa, Razão Cintura-Coxa e Índice de Adiposidade Corporal. Resultados: O estudo transversal envolveu 109 pacientes (50,3±12,2anos). Os homens apresentaram maior concentração de TAV. Presença de hipertensão arterial (HA), maior IMC e menor consumo de alimentos protetores associaram-se à maior concentração de TAV em homens (R²ajustado=46,4%); maior idade, presença de HA, maior IMC e consumo de álcool foram associadas ao TAV em mulheres (R2ajustado=17,6%). Houve maior variabilidade nos valores de CA no sexo feminino. A cintura mínima apresentou maior correlação com o TAV (r=0,70) em homens. Entre as mulheres, as medidas da CA apresentaram maior correlação com o TAS. A equação preditiva para os homens apresentou maior poder preditivo (64,1%), que o modelo desenvolvido para as mulheres (40,4%). Dos 51 pacientes submetidos à intervenção dietética, houve uma redução ponderal de 5,8(±6,2)% nos homens, com redução de 11,2(±7,9)% de TAV; 6,8(±11,2)% de TAS e 54,9% nos triglicérides. Entre as mulheres, a redução de 4,1(±2,5)% do peso inicial, resultou em uma diminuição de 11,1(±8,8)% de TAV; 5,6(±7,4)% de TAS, 12,2% no colesterol e 31,4% nos triglicérides. Conclusão: Múltiplos fatores determinam o volume de TAV e TAS em homens e mulheres. Maior variabilidade entre os sítios de medição de CA foi observada no sexo feminino. Nos homens, a cintura mínima apresentou melhor poder preditivo do TAV. Uma perda ponderal de aproximadamente 5% promoveu uma mobilização substancial de TAV e TAS, com potenciais benefícios cardiometabólicos. / Introduction: When in excess, subcutaneous adipose tissue (SAT), and, remarkably, visceral adipose tissue (VAT) predict cardiometabolic risks. Quantification methods of SAT, and VAT have limited use in clinical practice, and the identification of a simple, low cost, high value marker, to estimate visceral fat, is nedeed. Abdominal cirumference (AC) is a common method used as VAT‟s proxy. However, there‟s a great protocol variation for its execution, wich jeorpadizes its use, and the results‟ comparison. Objectives: To estimate concentration of VAT and SAT , and associated factors; to estimate variability of AC in different anatomical regions, and compare measurament sites performance as predictors of SAT, VAT, and cardiometabolic anormalities; to develop a predective model to estimate volume of VAT from athropometric criteria easily applied in clinical practice; to evaluate weight loss effect on VAT, and SAT, and also VAT reduction effects on cardiometabolic profile. Method: Two designs were developed: a cross-sectional study to analyse associated factors to SAT and VAT concentration, and methodological aspects of VAT valuation; a clinical intervention to verify the result of calorie restriction on VAT after 3 months, involving overweight adults assisted in a northeastern Brazilian hospital. VAT and SAT were quantified by computerized tomography. AC was measured in six different sites. Other anthropometric parameters evaluated were: Body Mass Index (BMI), Waist-Hip Ratio, Waist-Height Ratio, Sagittal Diameter, Sagittal Index, Conicity Index, Neck Circumference, Neck-Thigh Ratio, Waist-Thigh Ratio, Body Adiposity Index. Results: The transversal study involved 109 patients (50,3±12,2years). Higher concentration of VAT was found in males. Arterial Hypertension (AH), higher BMI , and lower ingestion of protective food were associated with higher concentration of VAT in men (R²adjusted=46.4%); older age, AH, higher BMI e alcohol consumption were associated to VAT in women (R2adjusted=17.6%). Greater variability on AC values was found in females. Minimal waist size showed greater correlation with VAT (r=0,70) in males. Among women, AC measures demonstrated greater correlation with SAT. Predictive equation for men exposed higher predictive power (64.1%) than the model developed for women (40.4%). There was a weight loss of 5.8(±6.2)% in males from the 51 patientes submitted to intervention on diet, a reduction of VAT of 11.2(±7.9)%; 6.8(±11.2)% of SAT, and 54.9% of triglycerides. Among females, reduction of 4.1(±2.5)% from the initial weight resulted in a decrease of 11.1(±8.8)% of VAT; 5.6(±7.4)% of SAT, 12.2% of choleterol, and 31,4% of triglycerides. Conclusion: Multiple factors determine volume of VAT and SAT in men and women. Greater variability of measurement sites were observed in females. Among men, minimal waist determined better predictive power of VAT. A 5% loss of weight promoted a significant mobilization of SAT and VAT, with potential cardiometabolic benefits.