Global variations in diabetes mellitus based on fasting glucose and haemogloblin A1c

Fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c) are both used to diagnose diabetes, but may identify different people as having diabetes. We used data from 117 population-based studies and quantified, in different world regions, the prevalence of diagnosed diabetes, and whether those who were previously undiagnosed and detected as having diabetes in survey screening had elevated FPG, HbA1c, or both. We developed prediction equations for estimating the probability that a person without previously diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa. The age-standardised proportion of diabetes that was previously undiagnosed, and detected in survey screening, ranged from 30% in the high-income western region to 66% in south Asia. Among those with screen-detected diabetes with either test, the agestandardised proportion who had elevated levels of both FPG and HbA1c was 29-39% across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and middle-income regions, isolated elevated HbA1c more common than isolated elevated FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and underestimate diabetes prevalence. Our prediction equations help allocate finite resources for measuring HbA1c to reduce the global gap in diabetes diagnosis and surveillance.peer-reviewe

Genetic potential of broad-base populations of tropical maize targeting reciprocal recurrent selection

A seleção recorrente recíproca (SRR) favorece o desenvolvimento de linhagens endogâmicas com alto padrão heterótico. De certo que a SRR melhora a capacidade de combinação entre duas populações de melhoramento. Assim, o uso de populações mais divergentes geneticamente na SRR possibilita maiores ganhos por ciclo de seleção. Dessa forma, o objetivo com esse trabalho foi avaliar a heterose entre dez populações de base genética ampla de milho em diversas condições ambientais. Para isso, 45 populações bi-parentais (PBP's) e as dez populações parentais foram avaliadas, nas safras 2018/19 e 2019/20, em quatro ambientes: 1) ambiente tropical de terras baixas; 11) um com baixa disponibilidade de nitrogênio (N) e; 111) dois em condições normais de cultivo. O delineamento experimental utilizado foi o alfa látice 11 x 5, com três repetições. Cada parcela foi constituída por duas linhas de cinco metros, espaçadas em 0,80 m. Os caracteres avaliados foram: dias até florescimento masculino (FM, dias) e feminino (FF, dias); altura de planta (AP, cm) e de espiga (AE, cm) e; produtividade de grãos (PG, kg ha”!). Foi realizada a análise dialélica conjunta das safras de cada ambiente e outra envolvendo safras e ambientes. As análises dialélicas seguiram os modelos da Analysis I de Gardner e Eberhart. Os efeitos de variedade (v;) e heterose (h;;) foram significativos (P < 0,05), para quase todos os caracteres, exceto AP e AE em alguns ambientes. Os componentes da h;; foram quase todos significativos (P < 0,05) para PG nos ambientes avaliados. A h;; explicou majoritariamente a variação encontrada entre os genótipos avaliados para PG. Ao longo dos ambientes, as populações IPR164, UFVMI00(HS)CI e UFVM200(HS)CI obtiveram as melhores estimativas de v; para PG. A progenitora AL Avaré se demonstrou como a mais divergente geneticamente, pois apresentou altas estimativas de heterose varietal em todos os ambientes. Consequentemente, a Al Avaré obteve as estimativas mais favoráveis da capacidade geral de combinação (g;) para PG. A população IPR 164, devido ao alto v;, também apresentou estimativas favoráveis de g; para PG. As PBP's UFVM100(HS)CI/PRI64, UFVMI100(HS)CI/UFVM200(HS)CI e UFVM200/AL Avaré apresentaram heteroses específicas favoráveis para PG. Conclui-se que as populações avaliadas apresentaram divergência genéticas e podem ser usadas em programas de SRR para o desenvolvimento de linhagens com alto padrão heterótico.Palavras-chave: Zea mays L. dialelo. Gardner e Eberhart. Pré-melhoramento. Terras baixas. Baixo N.The reciprocal recurrent selection (RRS) allows the development of inbreed lines with a high heterotic pattern. Since, RRS aims to improve the combining ability between two populations. For this reason, use of more genetically divergent populations in SRR allows greater gains per cycle of selection. However, it is extremely important to know the heterosis (h;;) among the populations before starting the RRS program. Thus, the objective of this study was to evaluate the heterosis among ten tropical broad-base populations of maize under multiple environments. For this, 45 populations crosses and ten parental populations were evaluated, in 2018/19 and 201920 summer seasons, under lowland, low nitrogen (low N) and optimum conditions. The experimental design used was the 11 x 4 alpha lattice design with three replications. Each experimental unit consisted of two row of five-meter plot spaced 0.80 m. We evaluated the traits: days to pollen shedding (DTP, days), days to silking (DTS, days), plant height (PH, cm), ears height (EH, cm) and grain yield (GY, kg ha'!). The joint diallel analysis was carried out between the season of each environment and with all environments. The genetics and environmental effects were partitioned following the models of Gardner Eberhart Analysis II. The variety effect (v;) and heterosis (h;;) were significant (P<0,05) for all traits, except for PH and EH in some environments. The components of h;; were almost all significant (P<0,05) for GY. The h;; effects explained most of the differences among diallel entries for GY. Throughout the environments, the v; effects for GY was highest for IPR164, UFVMI100(HS)CI e UFVM200(HS)C1. The parental population AL Avaré 1s the most genetically divergent, because this populations showed the highest varietal heterosis effects 1n all environments for GY. Consequently, this population showed the most favorable estimates of general combining ability (GCA). The parental population IPR164, due the high v;, also presented favorable estimates of GCA for GY. The populations crosses UFVM100(HS)CI/IPRI64, UFVM100(HS)CI/UFVM200(HS)CI e UFVM200/AL Avaré showed the best estimates for specific heterosis effects for GY. We concluded that, the evaluated populations showed genetics divergence, which indicate they can be used in RRS programs for the development of lines with high heterotic pattern.Keywords. Zea mays L. Diallel. Gardner and Eberhart. Pre-breeding. Lowland. Low N.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológic

Physiological quality of popcorn seeds assessed by the accelerated aging test

Abstract: Despite the insufficient internal supply of popcorn kernel cultivars, the Brazilian production is continuously increasing. Therefore, searching for tests that offer fast results and reliable information on the physiological potential of the seeds is very important. The objective of this study was to assess the efficiency of the accelerated aging test, by using different times and exposure temperatures, for the evaluation of the physiological quality of popcorn seed lots. Popcorn seeds from three lots of the hybrid AP 8203 were used. For the initial characterization of the lots, the following tests were conducted: seed moisture content, first and final germination count, and field emergence. The accelerated aging test was performed in a 3x4x2 factorial scheme. After aging, the seeds were tested for moisture content, germination, and electrical conductivity. The experiment was carried out in a completely randomized design. The characteristic vigor was affected during aging, as evidenced by the increase in the amount of leachate detected by the electrical conductivity test. Seed lot 3 was most vigorous in the aging test conducted for 48 h at 45 °C. The accelerated aging test at 42 ºC for 48 h provides consistent information to differentiate seed lots of popcorn

Genotypic variation and relationships among traits for root morphology in a panel of tropical maize inbred lines under contrasting nitrogen levels

A strategy to increase nitrogen (N) use efficiency in maize is the genetic improvement of N acquisition through root morphology. Here, we quantified the genetic variation of 150 tropical maize inbred lines for root morphology and shoot traits and investigated the relationships among traits. We evaluated the inbred lines at the seedling stage in a greenhouse experiment under two treatments: high N and low N supply. A mixed model approach was used to estimate variance components. Canonical correlations were estimated between root- and shoot-related groups of traits, and the genetic diversity among inbred lines was determined. Our inbred line panel showed huge genetic variability for all traits and presented large genetic diversity under both N levels. Root dry weight (RDW) was associated with shoot dry weight (SDW) at high N, and RDW and total root length (TRL) were positively associated with SDW at low N. Based on SDW, RDW and TRL, we selected a set of the top 15 maize inbred lines to be used in maize breeding programs focusing on N-use efficiency. We therefore concluded that there is a significant diversity in tropical maize inbred lines, which have the genetic potential to produce N-efficient hybrids and maize breeding populations for N stress conditions

Global variation in diabetes diagnosis and prevalence based on fasting glucose and hemoglobin A1c

International audienceAbstract Fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) are both used to diagnose diabetes, but these measurements can identify different people as having diabetes. We used data from 117 population-based studies and quantified, in different world regions, the prevalence of diagnosed diabetes, and whether those who were previously undiagnosed and detected as having diabetes in survey screening, had elevated FPG, HbA1c or both. We developed prediction equations for estimating the probability that a person without previously diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa. The age-standardized proportion of diabetes that was previously undiagnosed and detected in survey screening ranged from 30% in the high-income western region to 66% in south Asia. Among those with screen-detected diabetes with either test, the age-standardized proportion who had elevated levels of both FPG and HbA1c was 29–39% across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and middle-income regions, isolated elevated HbA1c was more common than isolated elevated FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and underestimate diabetes prevalence. Our prediction equations help allocate finite resources for measuring HbA1c to reduce the global shortfall in diabetes diagnosis and surveillance

Global variation in diabetes diagnosis and prevalence based on fasting glucose and hemoglobin A1c

: Fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) are both used to diagnose diabetes, but these measurements can identify different people as having diabetes. We used data from 117 population-based studies and quantified, in different world regions, the prevalence of diagnosed diabetes, and whether those who were previously undiagnosed and detected as having diabetes in survey screening, had elevated FPG, HbA1c or both. We developed prediction equations for estimating the probability that a person without previously diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa. The age-standardized proportion of diabetes that was previously undiagnosed and detected in survey screening ranged from 30% in the high-income western region to 66% in south Asia. Among those with screen-detected diabetes with either test, the age-standardized proportion who had elevated levels of both FPG and HbA1c was 29-39% across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and middle-income regions, isolated elevated HbA1c was more common than isolated elevated FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and underestimate diabetes prevalence. Our prediction equations help allocate finite resources for measuring HbA1c to reduce the global shortfall in diabetes diagnosis and surveillance

Diminishing benefits of urban living for children and adolescents’ growth and development

Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1–6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m–2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified