Abstract

Background

Measurements of hormone concentrations in human milk from understudied populations across the world is of growing scientific interest. Due to limited access to suitable laboratory facilities at many research sites, human milk samples are often shipped frozen to distant laboratories for analysis. Shipping and handling exposes samples to the risk of thawing and degradation as the results of delays, mishandling, or other unforeseen circumstances. Similar degradation risk factors are well known in serum samples. However, the vulnerability of hormone degradation in human milk to thawing during transportation is largely unexplored. Leptin and adiponectin are of particular importance due to their roles in feeding behavior and metabolism in infants, hence our focus on these two hormones. In addition, leptin and adiponectin have been shown to be vulnerable to pasteurization temperature degradation in human milk samples.

Aims

We tested the degradation of human milk metabolic hormones – leptin and adiponectin – in a controlled environment in response to a variety of freeze/thaw conditions that are reflective of potential temperature fluctuations during transportation.

Materials & Methods

Human milk samples were experimentally subjected to thaw durations ranging from 4 to 16 h and assayed for hormonal levels to observe changes from baseline. Samples were also subjected to two additional experimental conditions, re-freezing after an extended period outside freezers or remaining thawed with additional ice packs, to investigate the impact of common transportation conditions.

Results

We found the assayed levels of leptin were not significantly impacted by an extended thaw cycle of 16 h. However, leptin levels were impacted by the extended period of 40 h outside of the freezer. Adiponectin showed a decrease in concentration percentage after the initial 16-h thaw period, but the increased degradation between 0–16 h and 16–40 h was not as severe as that seen in the leptin samples.

Discussion & Conclusion

The results of this experiment can be used to inform hormone measurement consistency given different thawing lengths or freezing conditions during transportation. Additionally, this research informs decisions regarding transportation, storage/handling, and data analysis in human milk research.

Abstract

Objectives

The aim of our study was to compare morphometric patterns of facial sexual dimorphism with strength-face relationship in members of two distinct populations of European and Central Asian origin: Russians and Tuvans.

Methods

Handgrip strength (HGS) measures and facial photographs were collected from Russian (n = 233) and Tuvan (n = 187) men and women. We digitized 70 landmarks and semilandmarks on full-face and 54 landmarks and semilandmarks on profile photos. This was done to capture variation in facial morphology. After that, we performed the shape regressions of landmarks' coordinates upon sex and HGS. Results were visualized in forms of thin-plate deformation grids and geometric morphometric morphs.

Results

In both populations, HGS was associated significantly with male facial shape only. In Russian men, strength-related changes of facial shape were almost completely in direction of increase in male-typicality. This was especially evident for the relative lower facial width, which was higher in men compared to women, as well as in stronger men compared to weaker ones. On the contrary, in Tuvans the lower face was relatively narrower in men than in women. However, the facial shape of strong Tuvan men was also associated with relatively wider lower face. Our results indicate that the effect of strength on facial shape is relatively independent of facial sexual dimorphism.

Conclusions

Our findings clearly demonstrate that physical strength is associated with the shape of the lower part of male faces even in populations with a mismatched direction of lower face sexual dimorphism.

Abstract

Objective

To determine whether macronutrient intake is associated with novel obesity indices, including the conicity index (CI), body adiposity index (BAI), abdominal volume index (AVI), body roundness index (BRI), and weight-adjusted-waist index (WWI).

Methodology

A cross-sectional survey was conducted with 491 adults (344 males and 147 females) working at different universities in Jordan (July–December 2019). Daily intake of energy (kcal), carbohydrates (g), protein (g), and fat (g) was obtained using 24-h recalls collected over 2 days. Additionally, obesity indices were calculated.

Results

Regardless of sex, energy, and carbohydrate intakes had a moderately significant positive association, whereas protein and fat intakes had a weakly significant association with BAI, AVI, and BRI. CI and WWI showed a weakly significant association with all macronutrients in males, a moderate correlation with energy and carbohydrate intake, and a weak association with fat and protein intake in females. Male participants had significant increases in the CI (T1 = 1.29 ± 0.01 vs. T3 = 1.36 ± 0.01, p = .018), AVI (T1 = 17.96 ± 0.52 vs. T3 = 22.81 ± 0.57, p = .011), and WWI (T1 = 10.72 ± 0.11 vs. T3 = 11.29 ± 0.09, p = .047) indices scores through the carbohydrate intake tertiles. Additionally, there was a significant increase in scores of AVI (T1 = 18.60 ± 0.56 vs. T3 = 21.42 ± 0.46, p = .048) and an almost significant increase in CI (T1 = 1.30 ± 0.01vs. T3 = 1.33 ± 0.01, p = .056) through the tertiles of protein intake.

Conclusion

Macronutrients were significantly associated with all indices. The effect of macronutrients on obesity indices is sex-based. Among men, CI, AVI, and WWI were the indices most affected by carbohydrate and protein intakes. Future studies should further investigate food sources and macronutrient quality.

Abstract

Background

With regard to the origin of its population and microevolutionary processes, Uruguay exhibits distinctive features that distinguish it from other countries in Latin America, while at the same time sharing several similarities. In this article, we will focus on the variability of paternal genetic lineages in two geographical regions with different histories that can be considered as examples of distinct populations for the continent. In general terms, the genetic diversity is a result of different demographic processes related to the American conquest and colonisation. These resulted in distinct ancestral components which vary geographical and depend on the distribution by sex within these components. In Uruguay, native maternal haplogroups are significantly more frequent in the North. Although there are several studies about the geneticvariability of Uruguay, little is known about male genetic lineages.

Aims

The aim of this work is to present an updated study of the male genetic variability of the Uruguayan population.

Methods

We analyzed 13 biallelic markers and 27 STRs located in the male-specific region of the Y chromosome for 157 males: 98 from the capital, Montevideo, and 59 from Tacuarembó.

Results

Almost all haplogroups found in both locations are European (99% and 93.2% respectively). One Sub-Saharan African haplogroup was found in Montevideo (1%) and 2 in Tacuarembó (3%), while Native haplogroups were found only in Tacuarembó, evidencing a strong sex-biased admixture. By crossing genetic and genealogical information we could relate European haplogroups with different waves and times of migrations.

Discussion

Network analysis indicated a very diverse male population, suggesting that European migrants came from heterogeneous geographic locations and in different waves. Tacuarembó has closer population affinities with Iberian populations while Montevideo is more diverse. Male population expansion expansion, can be explained by the large number of migrants that arrived during the XIX century and the first half of the XX century.

Conclusions

The Uruguayan male gene pool is the result of several migration waves with diverse origins, with strong sex-biased admixture that can be explained by the European migration, the violence against the indigenous males, and the segregation of the Africansadmixture that can be explained due to European migration, violence against Natives, and segregation against African males.admixture that can be explained due to European migration, violence against Natives, and segregation against African males.admixture that can be explained due to European migration, violence against Natives, and segregation against African males.admixture that can be explained due to European migration, violence against Natives, and segregation of hte Africans.

Abstract

Objectives

This study aimed to perform latent profile analysis (LPA) in older adult women with metabolic syndrome to extract a group according to their characteristics while controlling for body composition, blood lipid levels, and vascular function. The study also examined the relationship between different variables.

Methods

The participants were 35 women aged ≥65 years, who met the Korean female standards for metabolic syndrome. Blood collection, blood pressure measurements, and vascular function measurements were performed. LPA and multigroup path analysis (MGPA) were performed to statistically analyze the effects of body composition on blood lipid levels and vascular function in older adult women with metabolic syndrome. Mplus 8.3 and jamovi 2.0.0 were used for the analyses, and the control significance level was set at .05.

Results

The participants were divided into the following three groups: (G1) metabolically unhealthy participants with normal weight, (G2) normal-weight participants with arteriosclerosis, and (G3) obese but metabolically healthy participants (G3). The effect of body composition on blood lipid levels showed a significant difference only in G1. The effect of body composition on vascular function was influenced by various variables in G1 and G3, while G1 showed a higher explanatory power.

Conclusions

The MGPA results showed that the relationship between variables differs depending on the group. Therefore, the metabolic syndrome should be studied by subdividing it and confirming the characteristics of the classified groups, such as normal-weight but metabolically unhealthy individuals and obese but metabolically healthy individuals.

Abstract

Objectives

The REACT project was designed around two main aims: (1) to assess children's growth and motor development after the COVID-19 pandemic and (2) to follow their fundamental movement skills' developmental trajectories over 18 months using a novel technological device (Meu Educativo®) in their physical education classes. In this introductory article, the first of the Journal's special issue dedicated to REACT, our goal was to present the project rationale, its methodology, training and certification of the team, statistical approach, quality control, governance, and study management.

Methods

We sampled 1000 children (6–10 years of age) from 25 of the 32 primary schools in Matosinhos, northern Portugal. The protocol included a set of variables clustered around the child (growth, physical fitness, fundamental movement skills, and health behaviors), family (demographics, socioeconomic status, parental support for sports participation and physical activity), school (policies and practices for health behaviors, infrastructure for physical education and sports practices), and neighborhood and home environments (safety, sidewalks, sports facilities, as well as children electronic devices and play equipment at home). A set of standard protocols were implemented in REACT together with a rigorous system of training and certification of all members of the research team. This was complemented with a pilot study to assess, in loco, the quality of data acquisition, data entry, and control.

Discussion

Results from REACT will provide school administrators and teachers with novel and far-reaching information related to children's growth and motor development as well as health behaviors after the COVID-19 pandemic. It will also provide city-hall education officials with insight regarding children's physical fitness, fundamental movement skills, and sports practices that will be of great importance in devising novel intervention programs to increase health-enhancing physical activity, and combat sedentariness and obesity. Finally, it will offer parents a wealth of information regarding their children's growth, motor development, and health.

Abstract

Objectives

Both the immune system of human milk and milk cortisol have complex short- and long-term effects on child health and development. As understanding continues to grow of the independent effects of each of these components of milk, it is also important to investigate their intersection, including how milk cortisol affects the immune system of milk. We began this important endeavor through secondary analyses of archived milk specimens.

Methods

Participants were 31 lactating mothers from upstate New York. We estimated milk cortisol concentrations via enzyme immunoassay. We assessed milk proinflammatory cytokine (interleukin-6, IL-6) responses to pathogenic (Salmonella) and commensal (Escherichia, Lactobacillus, Bifidobacterium) bacteria via in vitro stimulation. We estimated ordered logistic regression models to assess associations between milk cortisol and IL-6 responses to bacteria.

Results

Milk cortisol ranged from 0.098 to 1.007 μg/dL. Milk cortisol was positively associated with IL-6 responses to S. enterica (B: 4.035; 95% CI: 0.674, 7.395) and B. breve (B: 3.675; 95% CI: 0.426, 6.924); this association persisted after controlling for child age. Results were less clear for associations between milk cortisol and IL-6 responses to L. acidophilus (B: 2.318; 95% CI: −1.224, 5.859) and E. coli (B: 2.366; 95% CI: −0.960, 5.692).

Conclusions

Complex interactions between cortisol and the immune system extend to milk. Milk cortisol was positively associated with proinflammatory responses to some bacteria in vitro. This may suggest that milk cortisol is causally upstream of protective immune activity.

Abstract

Objectives

To understand the distribution and secular trends of Chinese adult boys and girls and investigate their spatial network effects and determinants of spatial network effects.

Methods

Our study extracted data of 18-year-old boys and 17-year-old girls in China from the national students fitness and health survey reports in 1985, 2000, 2010, and 2019. A total of 89 839 participants were selected. The growth range and growth rate in each period were calculated. A neighborhood relationship network was created to share the common boundary.

Results

During the period 1985–2019, the average height of Chinese 18-year-old boys increased from 168.19 to 172.14 cm, and that of 17-year-old girls increased from 156.97 to 160.17 cm (all p trend <.05). Both boys and girls showed significant correlations in first- and second-level neighbors (all p < .05) with the most significant correlations in first-level neighbors (all p < .001). But there were no significant correlations in third-level neighbors. Height of girls and boys in each region was correlated with gross domestic product (GDP) per capita, urbanization rate, population density, longitude, and latitude. After controlling for factors with significance, only the initial regional height of girls in 2000 was positively correlated with first level neighborhood (p < .05).

Conclusion

Since 1985, the heights of Chinese boys aged 18 and girls aged 17 have been increasing and the increases accelerated. Height is related to nearer neighbors. After controlling GDP per capita, urbanization rate, population density, longitude and latitude, the correlations has almost disappeared.

Abstract

Objectives

Cross-population variation in age at menarche is related to many factors. The purpose of this study was to examine climate variables in relation to mean age at menarche among 87 modern human populations. We hypothesized a later age at menarche among populations living in areas with high precipitation variability, heavy seasonal rainfall, and high temperatures year-round due to water-borne diseases and periods of resource scarcity.

Methods

Using a comparative dataset, we examined geospatial distribution and climate variables in relation to age at menarche for 87 modern human populations.

Results

We found the strongest predictor of a later age at menarche was higher fertility followed by a later mean age at death. In addition, higher annual rainfall, higher precipitation seasonality, and lower annual mean temperature were moderate predictors of age at menarche.

Conclusions

We propose that later ages at menarche in countries with high fertility may be a life-history strategy developed in response to climatic conditions that have resulted in higher immunological load. In these conditions, females may prioritize growth rather than reproduction. Shifts in climate and global population growth may change the future biological landscape of age at menarche.