Hybrid vigor, fetal overgrowth, and viability of mice derived by nuclear cloning and tetraploid embryo complementation

To assess whether heterozygosity of the donor cell genome was a general parameter crucial for long-term survival of cloned animals, we tested the ability of embryonic stem (ES) cells with either an inbred or F1 genetic background to generate cloned mice by nuclear transfer. Most clones derived from five F1 ES cell lines survived to adulthood. In contrast, clones from three inbred ES cell lines invariably died shortly after birth due to respiratory failure. Comparison of mice derived from nuclear cloning, in which a complete blastocyst is derived from a single ES cell, and tetraploid blastocyst complementation, in which only the inner cell mass is formed from a few injected ES cells, allows us to determine which phenotypes depend on the technique or on the characteristics of the ES cell line. Neonatal lethality also has been reported in mice entirely derived from inbred ES cells that had been injected into tetraploid blastocysts (ES cell-tetraploids). Like inbred clones, ES cell-tetraploid pups derived from inbred ES cell lines died shortly after delivery with signs of respiratory distress. In contrast, most ES cell-tetraploid neonates, derived from six F1 ES cell lines, developed into fertile adults. Cloned pups obtained from both inbred and F1 ES cell nuclei frequently displayed increased placental and birth weights whereas ES cell-tetraploid pups were of normal weight. The potency of F1 ES cells to generate live, fertile adults was not lost after either long-term in vitro culture or serial gene targeting events. We conclude that genetic heterozygosity is a crucial parameter for postnatal survival of mice that are entirely derived from ES cells by either nuclear cloning or tetraploid embryo complementation. In addition, our results demonstrate that tetraploid embryo complementation using F1 ES cells represents a simple, efficient procedure for deriving animals with complex genetic alterations without the need for a chimeric intermediate.

Concentrações séricas de 25 (OH) e perfil metabólico mediados pela adiposidade

Introdução: Baixas concentrações séricas de hidroxivitamina D (25[OH]D) e o excesso de peso atingiram níveis epidêmicos em todo o mundo. Estudos relatam que concentrações séricas de vitamina D estão associadas às alterações lipídicas, glicolíticas e inflamatórias; e estas alterações são conhecidamente mediadas pela adiposidade. Dessa forma, a vitamina D pode atuar de forma benéfica sobre o perfil metabólico em adolescentes, adultos e idosos. Objetivo: Investigar e descrever as associações entre as concentrações séricas de 25(OH)D e o perfil metabólico, mediadas pela adiposidade em adolescentes, adultos e idosos. Metodologia: Inicialmente, foi utilizada subamostra do Inquérito de Saúde de São Paulo (ISA-Capital), estudo transversal, de base populacional (n=281), para investigar a associação entre as concentrações séricas de vitamina D e marcadores inflamatórios em adultos brasileiros. Posteriormente, foram utilizados dados do estudo Healthy Lifestyle in Europe by Nutrition in Adolescents-(HELENA), estudo multicêntrico transversal da população de adolescentes européia, com o intuito de avaliar as alterações nos marcadores lipídicos e de homeostase da glicose mediados pela deficiência de vitamina D e obesidade. Finalmente, foi analisada a amostra do estudo PHYSMED, um estudo transversal com idosos não institucionalizados para verificar associações entre concentrações séricas de vitamina D, perfil lipídico e composição corporal em idosos espanhóis aparentemente saudáveis. Resultados: Nos adultos, observou-se uma associação negativa entre as concentrações de TNF-alfa e de IL-6 e as concentrações séricas de 25(OH)D em indivíduos com peso normal. Nos adolescentes, as concentrações de 25(OH)D foram associadas de forma independente e positiva com o Quantitative Insulin Sensitivity Check Index-QUICKI (p <0.001) e negativamente associada com o IMC (p <0.05). Também foi observado que o aumento do IMC esteve associado com um aumento de 1.93 vezes maior chance de deficiência de vitamina D (IC de 95 por cento = 1.03 - 3.62; p = 0.040). Em idosos, verificou-se que as concentrações séricas de 25(OH)D foram associadas com o IMC (p = 0.04), a circunferência da cintura (p = 0.004), CT/HDL-c (p = 0.026) e o HDL-c (p = 0.001). Adicionalmente, foi observado que idosos com concentrações de HDL-c <40mg/dl possuíam 1.7 vezes maior chance de apresentarem deficiência de vitamina D em comparação com aqueles que possuíam concentrações de HDL-c >40 mg/dl (95 por cento IC = 1.10 a 2.85; p = 0.017) e o aumento na circunferência da cintura também foi associado com um maior risco de deficiência de vitamina D (95 por cento IC =0.96-1.00; p = 0.04). Conclusão: A composição corporal interage com as concentrações de 25(OH)D modulando a resposta inflamatória, à homeostase da glicose e também o perfil lipídico. Indivíduos sem deficiência de vitamina D apresentam melhor perfil metabólico e também melhor composição, sugerindo que a suficiência de vitamina D pode ter um papel importante nas condições metabólicas mediadas pela adiposidade.

Organização e dinâmica psíquica na obesidade infantil

Instrumentos de avaliação psicológica constituem-se em métodos sistemáticos de investigação e de compreensão de componentes estruturais e funcionais do comportamento humano, com diversificados objetivos e estratégias técnicas, respeitando-se especificidades das etapas do desenvolvimento. Em processos de avaliação psicológica de características da personalidade, os métodos projetivos, como o Método de Rorschach e o Desenho da Figura Humana, são recursos amplamente utilizados, contribuindo para a compreensão e elaboração de intervenções terapêuticas em variados campos de aplicação, como na área da obesidade infantil. Nesse contexto, este trabalho teve por objetivo identificar e comparar características psicológicas de crianças com obesidade em relação a eutróficas, a partir de métodos projetivos de investigação da personalidade. Foram examinadas 60 crianças de sete a 11 anos de idade, sendo 30 crianças diagnosticadas como obesas e em tratamento específico para o transtorno (Grupo 1 - G1) e 30 crianças com peso normal (Grupo 2 - G2), sem atraso acadêmico, sem limites cognitivos e sem histórico de outras doenças físicas. Os participantes de G1 foram recrutados em instituições de saúde voltadas ao tratamento da obesidade infantil e G2 foi constituído a partir de parceria estabelecida com instituição de ensino bem como a partir de contatos informais da pesquisadora e de seu grupo de pesquisa (técnica da \"bola de neve\"), buscando-se balanceamento dos grupos por sexo e idade. Os seguintes instrumentos de avaliação psicológica foram aplicados individualmente nas crianças: Teste das Matrizes Progressivas Coloridas de Raven (critério de seleção de participantes, incluindo-se na amostra apenas crianças com resultados intelectuais médios ou superiores), o Desenho da Figura Humana e o Método de Rorschach (Escola Francesa). Os pais das crianças participantes responderam ao Questionário de Capacidades e Dificuldades (SDQ) para caracterização da amostra. Os resultados foram examinados conforme padronização específica dos respectivos manuais técnicos dos instrumentos, realizando-se análises descritivas e inferenciais, a fim de examinar possíveis associações entre variáveis clínicas e demográficas e indicadores de características de personalidade das crianças. Foram efetuadas análises correlacionais entre resultados no DFH e no Rorschach, considerando também a classificação nutricional da criança. Os achados permitem compreender características do funcionamento psíquico envolvidas na obesidade infantil, de modo a favorecer estratégias futuras de intervenção terapêutica com crianças. (CAPES)

Cuidar no parto : prática de episiotomia

Enquadramento – A episiotomia é uma incisão feita no períneo para aumentar o canal vaginal com o objetivo de evitar outros traumas perineais durante o parto. No entanto, esta prática, por si só, já se considera um trauma perineal pelo corte em estruturas que podem desencadear problemas futuros. A Organização Mundial de Saúde (1996) recomenda a utilização limitada da episiotomia uma vez que não existem evidências credíveis de que a utilização generalizada ou de rotina desta prática tenha um efeito benéfico. Objetivos: Demonstrar evidência científica dos determinantes da prática de episiotomia seletiva em mulheres com parto normal/eutócico; identificar a prevalência de episiotomia; analisar os fatores (variáveis sociodemográficas, variáveis relativas ao recém-nascido, variáveis contextuais da gravidez e contextuais do parto) que influenciam na ocorrência de episiotomia. Métodos: O estudo empírico I seguiu a metodologia de revisão sistemática da literatura. Efetuou-se uma pesquisa na EBSCO, PubMed, SciELO, RCAAP de estudos publicados entre janeiro de 2008 e 23 de dezembro de 2014. Os estudos encontrados foram avaliados tendo em consideração os critérios de inclusão previamente estabelecidos. Dois revisores avaliaram a qualidade dos estudos a incluir utilizando a grelha para avaliação crítica de um estudo descrevendo um ensaio clínico prospetivo, aleatorizado e controlado de Carneiro (2008). Após avaliação crítica da qualidade, foram incluídos no corpus do estudo 4 artigos nos quais se obteve um score entre 87,5% e 95%. O estudo empírico II enquadra-se num estudo quantitativo, transversal, descritivo e retrospetivo, desenvolvido no serviço de Obstetrícia do Centro Hospitalar Cova da Beira, segundo um processo de amostragem não probabilística por conveniência (n = 382). A recolha de dados efetuou-se através da consulta dos processos clínicos das mulheres com idade ≥ 18 anos que tiveram um parto vaginal com feto vivo após as 37 semanas de gestação. Resultados: Evidência de que a episiotomia não deve ser realizada de forma rotineira, cujo uso deve restringir-se a situações clínicas específicas. A episiotomia seletiva, comparada com a episiotomia de rotina, está relacionada com um menor risco de trauma do períneo posterior, a uma menor necessidade de sutura e a menos complicações na cicatrização. Amostra constituída por 382 mulheres, na faixa etária dos 18-46 anos. Apenas, não se procedeu à episiotomia em 41,7% da amostra, apontando para a presença da episiotomia seletiva. Número significativo de mulheres com parto eutócico (80,5%), com sutura (95,0%), laceração de grau I (64,9%), dor perineal (89,1%) sujeitas a episiotomia (58,3%). A maioria dos recém-nascidos nasceram com peso normal (92,3%), com um valor expressivo de mulheres sujeitas a episiotomia (91,4%). Ainda se constatou a existência de casos, apesar de reduzidos, em que o recém-nascido nasceu macrossómico (5,4%), tendo-se recorrido igualmente a esta prática. Não há uma associação direta entre a realização de episiotomia e os scores do APGAR. Conclusão: Face a estes resultados e com base na evidência científica disponível que recomenda, desde há vários anos, que se faça um uso seletivo da episiotomia, sugere-se que os profissionais de saúde estejam mais despertos para esta realidade, de modo a que se possam anular as resistências e as barreiras de mudanças por parte dos mesmos face ao uso seletivo da episiotomia. Para promover essa mudança de comportamentos é importante não só mostrar as evidências científicas, bem como transpô-las para a prática, capacitando os profissionais de saúde, sobretudo os enfermeiros, na sua atuação. Palavras-chave: Parto Normal/eutócico; Episiotomia; Episiotomia seletiva; Episiotomia de rotina.

The influence of parent's body mass index on peer selection: An experimental approach using virtual reality

Relatively little is known about the influence of psychosocial factors, such as familial role modeling and social network on the development and maintenance of childhood obesity. We investigated peer se- lection using an immersive virtual reality environment. In a virtual schoolyard, children were confronted with normal weight and overweight avatars either eating or playing. Fifty-seven children aged 7–13 participated. Interpersonal distance to the avatars, child's BMI, self-perception, eating behavior and parental BMI were assessed. Parental BMI was the strongest predictor for the children's minimal distance to the avatars. Specifically, a higher mothers' BMI was associated with greater interpersonal distance and children approached closer to overweight eating avatars. A higher father's BMI was associated with a lower interpersonal distance to the avatars. These children approached normal weight playing and overweight eating avatar peers closest. The importance of parental BMI for the child's social approach/ avoidance behavior can be explained through social modeling mechanisms. Differential effects of pa- ternal and maternal BMI might be due to gender specific beauty ideals. Interventions to promote social interaction with peer groups could foster weight stabilization or weight loss in children.

Risk of Cerebral Venous Thrombosis in Obese Women.

IMPORTANCE Obesity is a risk factor for deep vein thrombosis of the leg and pulmonary embolism. To date, however, whether obesity is associated with adult cerebral venous thrombosis (CVT) has not been assessed. OBJECTIVE To assess whether obesity is a risk factor for CVT. DESIGN, SETTING, AND PARTICIPANTS A case-control study was performed in consecutive adult patients with CVT admitted from July 1, 2006 (Amsterdam), and October 1, 2009 (Berne), through December 31, 2014, to the Academic Medical Center in Amsterdam, the Netherlands, or Inselspital University Hospital in Berne, Switzerland. The control group was composed of individuals from the control population of the Multiple Environmental and Genetic Assessment of Risk Factors for Venous Thrombosis study, which was a large Dutch case-control study performed from March 1, 1999, to September 31, 2004, and in which risk factors for deep vein thrombosis and pulmonary embolism were assessed. Data analysis was performed from January 2 to July 12, 2015. MAIN OUTCOMES AND MEASURES Obesity was determined by body mass index (BMI). A BMI of 30 or greater was considered to indicate obesity, and a BMI of 25 to 29.99 was considered to indicate overweight. A multiple imputation procedure was used for missing data. We adjusted for sex, age, history of cancer, ethnicity, smoking status, and oral contraceptive use. Individuals with normal weight (BMI <25) were the reference category. RESULTS The study included 186 cases and 6134 controls. Cases were younger (median age, 40 vs 48 years), more often female (133 [71.5%] vs 3220 [52.5%]), more often used oral contraceptives (97 [72.9%] vs 758 [23.5%] of women), and more frequently had a history of cancer (17 [9.1%] vs 235 [3.8%]) compared with controls. Obesity (BMI ≥30) was associated with an increased risk of CVT (adjusted odds ratio [OR], 2.63; 95% CI, 1.53-4.54). Stratification by sex revealed a strong association between CVT and obesity in women (adjusted OR, 3.50; 95% CI, 2.00-6.14) but not in men (adjusted OR, 1.16; 95% CI, 0.25-5.30). Further stratification revealed that, in women who used oral contraceptives, overweight and obesity were associated with an increased risk of CVT in a dose-dependent manner (BMI 25.0-29.9: adjusted OR, 11.87; 95% CI, 5.94-23.74; BMI ≥30: adjusted OR, 29.26; 95% CI, 13.47-63.60). No association was found in women who did not use oral contraceptives. CONCLUSIONS AND RELEVANCE Obesity is a strong risk factor for CVT in women who use oral contraceptives.

The Effect of Fructose vs. Glucose Beverages on Low-Grade Systemic Inflammation

Thesis (Ph.D.)--University of Washington, 2016-04

Adjusting Body Cell Mass for Size in Women of Differing Nutritional Status

Background: Body cell mass (BCM) may be estimated in clinical practice to assess functional nutritional status, eg, in patients with anorexia nervosa. Interpretation of the data, especially in younger patients who are still growing, requires appropriate adjustment for size. Previous investigations of this general issue have addressed chemical rather than functional components of body composition and have not considered patients at the extremes of nutritional status, in whom the ability to make longitudinal comparisons is of particular importance. Objective: Our objective was to determine the power by which height should be raised to adjust BCM for height in women of differing nutritional status. Design: BCM was estimated by K-40 counting in 58 healthy women, 33 healthy female adolescents, and 75 female adolescents with anorexia nervosa. The relation between BCM and height was explored in each group by using log-log regression analysis. Results: The powers by which height should be raised to adjust BCM,A,ere 1.73. 1.73, and 2.07 in the women, healthy female adolescents, and anorexic female adolescents, respectively. A simplified version of the index, BCM/height(2), was appropriate for all 3 categories and was negligibly correlated with height. Conclusions: In normal-weight women, the relation between height and BCM is consistent with that reported previously between height and fat-free mass. Although the consistency of the relation between BCM and fat-free mass decreases with increasing weight loss, the relation between height and BCM is not significantly different between normal-weight and underweight women. The index BCM/height(2) is easy to calculate and applicable to both healthy and underweight women. This information may be helpful in interpreting body-composition data in clinical practice.

Intrauterine growth restriction due to uteroplacental vascular insufficiency leads to increased hypoxia-induced cerebral apoptosis in newborn piglets

Uteroplacental vascular insufficiency in humans is a common cause of intrauterine growth restriction (IUGR) and is associated with an increased incidence of perinatal asphyxia and neurodevelopmental disorders compared to normal weight newborns. Experimental models that provide an opportunity to analyze the pathogenesis of these relationships are limited. Here, we used neonatal pigs from large litters in which there were piglets of normal birth weight (for controls) and of low birth weight (for uteroplacental vascular insufficiency). Hypoxia was induced in paired littermates by reducing the fraction of inspired oxygen to 4% for 25 min. Brain tissue was collected 4 h post-hypoxia. Cerebral levels of apoptosis were quantified morphologically and verified with caspase-3 activity and TUNEL. Expression of Bcl-2, BcI-XL and Bax proteins was investigated using immunohistochemistry. Cellular positivity for Bcl-2 was consistently higher in the non-apoptotic white matter of the hypoxic IUGR animals compared with their littermates and reached significance at P < 0.05 in several pairs of littermates. Alterations in Bax showed a trend towards higher expression in the hypoxic IUGR littermates but rarely reached significance. The IUGR piglets showed a significantly greater amount of apoptosis in response to the hypoxia than the normal weight piglets, suggesting an increased vulnerability to apoptosis in the IUGR piglets. (c) 2006 Elsevier B.V. All rights reserved.

Adult obesity and number of years lived with and without cardiovascular disease

Objective: To determine the differences in number of years lived free of cardiovascular disease (CVD) and number of years lived with CVD between men and women who were obese, pre-obese, or normal weight at 45 years of age. Research Methods and Procedures: We constructed multistate life tables for CVD, myocardial infarction, and stroke, using data from 2551 enrollees (1130 men) in the Framingham Heart Study who were 45 years of age. Results: Obesity and pre-obesity were associated with fewer number of years free of CVD, myocardial infarction, and stroke and an increase in the number of years lived with these diseases. Forty-five-year-old obese men with no CVD survived 6.0 years [95% confidence interval (CI), 4.1; 8.1] fewer than their normal weight counterparts, whereas, for women, the difference between obese and normal weight subjects was 8.4 years (95% CI: 6.2; 10.8). Obese men and women lived with CVD 2.7 (95% CI: 1.0; 4.4) and 1.4 years (95% CI: -0.3; 3.2) longer, respectively, than normal weight individuals. Discussion: In addition to reducing life expectancy, obesity before middle age is associated with a reduction in the number of years lived free of CVD and an increase in the number of years lived with CVD. Such information is paramount for preventive and therapeutic decision-making by individuals and practitioners alike.

Relationships of activity and sugar drink intake on fat mass development in youths

Purpose: To determine whether a significant relationship exists between fat mass (FM) development and physical activity (PA) and/or sugar-sweetened drink (SD) consumption in healthy boys and girls aged 8-19 yr. Methods: A total of 105 males and 103 females were assessed during childhood and adolescence for a maximum of 7 yr and a median of 5 yr. Height was measured biannually. Fat-free mass (FFM) and FM were assessed annually by dual x-ray absorptiometry (DXA). PA was evaluated two to three times annually using the PAQ-C/A. Energy intake and SD were assessed using a 24-h dietary intake questionnaire also completed two to three times per year. Years from peak height velocity were used as a biological maturity age indicator. Multilevel random effects models were used to test the relationship. Results: When controlling for maturation, FFM, and energy intake adjusted for SD, PA level was negatively related to FM development in males (P < 0.05) but not in females (P > 0.05). In contrast, there was no relationship between SD and FM development of males or females (P > 0.05). There was also no interaction effect between SD and PA (P > 0.05) with FM development. Conclusion: This finding tends support to the idea that increasing PA in male youths aids in the control of FM development. Models employed showed no relationship between SD and FM in either gender.

Use of latent profile analysis to identify eating disorder phenotypes in an adult Australian twin cohort

Context: The relationships among the different eating disorders that exist in the community are poorly understood, especially for residual disorders in which bingeing or purging occurs in the absence of other behaviors. Objective: To examine a community sample for the number of mutually exclusive weight and eating profiles. Design: Data regarding lifetime eating disorder symptoms and weight range were submitted to a latent profile analysis. Profiles were compared regarding personality, current eating and weight, retrospectively reported life events, and lifetime depressive psychopathology. Setting: Longitudinal study among female twins from the Australian Twin Registry in whom eating was assessed by a telephone interview. Participants: A community sample of 1002 twins (individuals) who had participated in earlier waves of data collection. Main Outcome Measures: Number and clinical character of latent profiles. Results: The best fit was a 5-profile solution with women who were (1) of normal weight with few lifetime eating disorders (4.3%), (2) overweight (10.6% had a lifetime eating disorder), (3) underweight and generally had no eating disorders except for 5.3% who had restricting anorexia nervosa, (4) of low to normal weight (89.0% had a lifetime eating disorder), and (5) obese (37.0% had a lifetime eating disorder). Each profile contained more than 1 type of lifetime eating disorder except for the third profile. Women in the first and third profiles had the best functioning, with women in the fourth and fifth profiles having similarly poorer functioning. The women in the fourth group had a symptom profile distinctive from the other 4 groups in terms of severity; they were also more likely to have had lifetime major depression and suicidality. Conclusion: Lifetime weight ranges and the severity of eating disorder symptoms affected clustering more than the type of eating disorder symptom.

The prevalence and impact of overweight and obesity in an Australian obstetric population

Objective: To assess the prevalence and impact of overweight and obesity in an Australian obstetric population. Design, setting and participants: The Mater Mother's Hospital (MMH), South Brisbane, is an urban tertiary referral maternity hospital. We reviewed data for the 18401 women who were booked for antenatal care at the MMH, delivered between January 1998 and December 2002, and had a singleton pregnancy. Of those women, 14 230 had an estimated pre-pregnancy body mass index (BMI) noted in their record; 2978 women with BMI 40 kg/m(2)). Main outcome measures: Prevalence of overweight and obesity in an obstetric population; maternal, peripartum and neonatal outcomes associated with raised BMI. Results: Of the 14230 women, 6443 (45%) were of normal weight, and 4809 (34%) were overweight, obese or morbidly obese. Overweight, obese and morbidly obese women were at increased risk of adverse outcomes (figures represent adjusted odds ratio [AOR] [95% Cl]): hypertensive disorders of pregnancy (overweight 1.74 [1.45-2.15], obese 3.00 [2.40-3.74], morbidly obese 4.87 [3.27-7.24]); gestational diabetes (overweight 1.78 [1.25-2.52], obese 2.95 [2.05-4.25], morbidly obese 7.44 [4.42-12.54]); hospital admission longer than 5 days (overweight 1.36 [1.13-1.63], obese 1.49 [1.21-1.86], morbidly obese 3.18 [2.19-4.61]); and caesarean section (overweight 1.50 [1.36-1.66], obese 2.02 [1.79-2.29], morbidly obese 2.54 [1.94-3.321). Neonates born to obese and morbidly obese women had an increased risk of birth defects (obese 1.58 (1.02-2.46], morbidly obese 3.41 [1.67-6.94]); and hypoglycaemia (obese 2.57 [1.39-4.78], morbidly obese 7.14 [3.04-16.74]). Neonates born to morbidly obese women were at increased risk of admission to intensive care (2.77 [1.81-4.25]); premature delivery (< 34 weeks' gestation) (2.13 [1.13-4.01]); and jaundice (1.44 [1.09-1.89]). Conclusions: Overweight and obesity are common in pregnant women. Increasing BMI is associated with maternal and neonatal outcomes that may increase the costs of obstetric care. To assist in planning health service delivery, we believe that BMI should be routinely recorded on perinatal data collection sheets

The structural permeability of concrete at cryogenic temperatures

The thesis describes a programme of research designed to identify concretes for application at cryogenic temperature, in particular for storage of Liquefield Natural Gas which is maintained at a temperature of -165oC. The programme was undertaken in two stages. Stage 1 involved screening tests on seventeen concrete mixes to investigate the effects of strength grade (and water/cement ratio), air entrainment, aggregate type and cement type. Four mixes were selected on the basis of low temperature strength, residual strength after thermal cycling and permeability at ambient temperature. In Stage 2 the selected mixes were subjected to a comprehensive range of tests to measure those properties which determine the leak tightness of a concrete tank at temperatures down to -165oC. These included gas permeability; tensile strength, strain capacity, thermal expansion coefficient and elastic modulus, which in combination provide a measure of resistance to cracking; and bond to reinforcement, which is one of the determining factors regarding crack size and spacing. The results demonstrated that the properties of concrete were generally enhanced at cryogenic temperature, with reduced permeability, reduced crack proneness and, by virtue of increased bond to reinforcement, better control of cracking should it occur. Of the concretes tested, a lightweight mix containing sintered PFA aggregate exhibited the best performance at ambient and cryogenic temperature, having appreciably lower permeability and higher crack resistance than normal weight concretes of the same strength grade. The lightweight mix was most sensitive to thermal cycling, but there was limited evidence that this behaviour would not be significant if the concrete was prestressed. Relationships between various properties have been identified, the most significant being the reduction in gas permeability with increasing strain capacity. The structural implications of the changing properties of the concrete have also been considered.

Beyond BMI: The “Metabolically healthy obese” phenotype & its association with clinical/subclinical cardiovascular disease and all-cause mortality -- a systematic review

Background A subgroup has emerged within the obese that do not display the typical metabolic disorders associated with obesity and are hypothesized to have lower risk of complications. The purpose of this review was to analyze the literature which has examined the burden of cardiovascular disease (CVD) and all-cause mortality in the metabolically healthy obese (MHO) population. Methods Pubmed, Cochrane Library, and Web of Science were searched from their inception until December 2012. Studies were included which clearly defined the MHO group (using either insulin sensitivity and/or components of metabolic syndrome AND obesity) and its association with either all cause mortality, CVD mortality, incident CVD, and/or subclinical CVD. Results A total of 20 studies were identified; 15 cohort and 5 cross-sectional. Eight studies used the NCEP Adult Treatment Panel III definition of metabolic syndrome to define “metabolically healthy”, while another nine used insulin resistance. Seven studies assessed all-cause mortality, seven assessed CVD mortality, and nine assessed incident CVD. MHO was found to be significantly associated with all-cause mortality in two studies (30%), CVD mortality in one study (14%), and incident CVD in three studies (33%). Of the six studies which examined subclinical disease, four (67%) showed significantly higher mean common carotid artery intima media thickness (CCA-IMT), coronary artery calcium (CAC), or other subclinical CVD markers in the MHO as compared to their MHNW counterparts. Conclusions MHO is an important, emerging phenotype with a CVD risk between healthy, normal weight and unhealthy, obese individuals. Successful work towards a universally accepted definition of MHO would improve (and simplify) future studies and aid inter-study comparisons. Usefulness of a definition inclusive of insulin sensitivity and stricter criteria for metabolic syndrome components as well as the potential addition of markers of fatty liver and inflammation should be explored. Clinicians should be hesitant to reassure patients that the metabolically benign phenotype is safe, as increased risk cardiovascular disease and death have been shown.