bluuebunny/crossref_metadata_2025_split huggingface dataset:
Association Between Markers of Adiposity During Childhood and Puberty Onset in Latino Girls
Authors: Pereira Ana , Ferrer Pedro , Binder Alexandra , Rojas Joanna , Michels Karin B , Corvalán Camila , Mericq Verónica 
Published: May 2023

Abstract

Context
Prepubertal adiposity is associated with earlier puberty. It is unclear when this association starts, if all adiposity markers are similarly associated, and whether all pubertal milestones are similarly affected.

Objective
To evaluate the association between different adiposity markers during childhood and the timing of different pubertal milestones in Latino girls.

Design, Setting, and Participants
Longitudinal follow-up of 539 female participants of the Chilean Growth and Obesity Cohort recruited from childcare centers (mean age 3.5 years) from the southeast area of Santiago, Chile. Participants were singletons born between 2002 and 2003 within the normal birthweight range. Since 2006, a trained dietitian measured weight, height, waist circumference (WC) and skinfolds to estimate body mass index (BMI) Centers for Disease Control and Prevention percentiles, central obesity, percentage of fat mass (%FM), and fat mass index (FMI, fat mass/height2).

Main Outcome
Since 2009, sexual maturation was assessed every 6 months to assess age at (1) thelarche, (2) pubarche, (3) menarche, and (4) peak height velocity (PHV).

Results
At thelarche, 12.5% were obese and 2% had central obesity. The median age of pubarche, menarche, and PHV were all associated with markers of adiposity at different time points during childhood whereas thelarche only with %FM and FMI. Adiposity clusters models showed that children with trajectories of high WC, %FM, and FMI during childhood were related with earlier thelarche, pubarche, menarche, and PHV but BMI trajectories only with menarche and PHV.

Conclusions
Higher WC, %FM, and FMI were associated with earlier age at thelarche, pubarche, menarche, and PHV. The effect of BMI was less consistent.
The Making and Breaking of a Popular Front: The Case of the National Negro Congress
Authors: Arnesen Eric 
Published: May 2023

AbstractDrawing together members of the American Communist Party and a variety of non-Communist progressives in the common cause of racial equality, labor rights, and antifascism, the National Negro Congress represented a visible example of the Popular Front (1935/1936 – 39) in action. This article explores how a Popular Front alliance came into being by tracing the events of 1935 that led Communists to eschew their prior sectarianism and non-Communists to recognize the value of collaboration with their now-former rivals. It also contends that contrary to what some recent scholarship argues, from the outset the Communist influence on the NNC's formation and operation was considerable — even decisive — and that after the signing of the 1939 Hitler-Stalin Pact, the party's new antiwar stance and its numerical dominance at the NNC's third conference in 1940 led to the collapse of the Popular Front alliance. Understanding the rise and fall of the NNC as a progressive coalition requires a critical evaluation of the role of the Communist Party in the NNC's accomplishments and failures.
Physiological and life history changes associated with seasonal adaptation in the cactophilic Drosophila mojavensis
Authors: Shaible Tierney M. , Matzkin Luciano M. 
Published: May 2023

ABSTRACT
Many insects inhabiting temperate climates are faced with changing environmental conditions throughout the year. Depending on the species, these environmental fluctuations can be experienced within a single generation or across multiple generations. Strategies for dealing with these seasonal changes vary across populations. Drosophila mojavensis is a cactophilic Drosophila species endemic to the Sonoran Desert. The Sonoran Desert regularly reaches temperatures of 50°C in the summer months. As individuals of this population are rare to collect in the summer months, we simulated the cycling temperatures experienced by D. mojavensis in the Sonoran Desert from April to July (four generations) in a temperature- and light-controlled chamber, to understand the physiological and life history changes that allow this population to withstand these conditions. In contrast to our hypothesis of a summer aestivation, we found that D. mojavensis continue to reproduce during the summer months, albeit with lower viability, but the adult survivorship of the population is highly reduced during this period. As expected, stress resistance increased during the summer months in both the adult and the larval stages. This study examines several strategies for withstanding the Sonoran Desert summer conditions which may be informative in the study of other desert endemic species.
Organoids as a tool for understanding immune-mediated intestinal regeneration and development
Authors: Jowett Geraldine M. , Coales Isabelle , Neves Joana F. 
Published: May 2023

ABSTRACT
The traditional view of immune cells is that their role within the body is to combat infections; however, it is becoming increasingly clear that they also perform tasks that are not classically associated with inflammation and pathogen clearance. These functions are executed deep within tissues, which are often poorly accessible and subject to environmental variability, especially in humans. Here, we discuss how multicellular 3D systems in a dish – organoids – are transitioning from a proof-of-principle approach to a timely, robust and reliable tool. Although we primarily focus on recent findings enabled by intestinal organoids co-cultured with lymphocytes, we posit that organoid co-culture systems will support future efforts to disentangle the interactions between a plethora of different cell types throughout development, homeostasis, regeneration and disease.
Heme-deficient primitive red blood cells induce HSPC ferroptosis by altering iron homeostasis during zebrafish embryogenesis
Authors: Lv Peng , Liu Feng 
Published: May 2023

ABSTRACT
The crosstalk between hematopoietic lineages is important for developmental hematopoiesis. However, the role of primitive red blood cells (RBCs) in the formation of definitive hematopoietic stem and progenitor cells (HSPCs) is largely unknown. Primitive RBC deficiencies in mammals always lead to early embryonic lethality, but zebrafish lines with RBC deficiencies can survive to larval stage. By taking advantage of a zebrafish model, we find that the survival of nascent HSPCs is impaired in alas2- or alad-deficient embryos with aberrant heme biosynthesis in RBCs. Heme-deficient primitive RBCs induce ferroptosis of HSPCs through the disruption of iron homeostasis. Mechanistically, heme-deficient primitive RBCs cause blood iron-overload via Slc40a1, and an HSPC iron sensor, Tfr1b, mediates excessive iron absorption. Thus, iron-induced oxidative stress stimulates the lipid peroxidation, which directly leads to HSPC ferroptosis. Anti-ferroptotic treatments efficiently reverse HSPC defects in alas2 or alad mutants. HSPC transplantation assay reveals that the attenuated erythroid reconstitution efficiency may result from the ferroptosis of erythrocyte-biased HSPCs. Together, these results illustrate that heme-deficient primitive RBCs are detrimental to HSPC production and may provide potential implications for iron dysregulation-induced hematological malignancies.
Cell competition from development to neurodegeneration
Authors: Costa-Rodrigues Carolina , Couceiro Joana , Moreno Eduardo 
Published: May 2023

ABSTRACT
Cell competition is a process by which suboptimal cells are eliminated to the benefit of cells with higher fitness. It is a surveillance mechanism that senses differences in the fitness status by several modes, such as expression of fitness fingerprints, survival factor uptake rate and resistance to mechanical stress. Fitness fingerprints-mediated cell competition recognizes isoforms of the transmembrane protein Flower, and translates the relative fitness of cells into distinct fates through the Flower code.
Impairments in cell competition potentiate the development of diseases like cancer and ageing-related pathologies. In cancer, malignant cells acquire a supercompetitor behaviour, killing the neighbouring cells and overtaking the tissue, thus avoiding elimination. Neurodegenerative disorders affect millions of people and are characterized by cognitive decline and locomotor deficits. Alzheimer's disease is the most common form of dementia, and one of the largely studied diseases. However, the cellular processes taking place remain unclear.
Drosophila melanogaster is an emerging neurodegeneration model due to its versatility as a tool for genetic studies. Research in a Drosophila Alzheimer's disease model detected fitness markers in the suboptimal and hyperactive neurons, thus establishing a link between cell competition and Alzheimer's disease.
In this Review, we overview cell competition and the new insights related to neurodegenerative disorders, and discuss how research in the field might contribute to the development of new therapeutic targets for these diseases.
Displacement experiments provide evidence for path integration in Drosophila
Authors: Titova Anna V. , Kau Benedikt E. , Tibor Shir , Mach Jana , Vo-Doan T. Thang , Wittlinger Matthias , Straw Andrew D. 
Published: May 2023

ABSTRACT
Like many other animals, insects are capable of returning to previously visited locations using path integration, which is a memory of travelled direction and distance. Recent studies suggest that Drosophila can also use path integration to return to a food reward. However, the existing experimental evidence for path integration in Drosophila has a potential confound: pheromones deposited at the site of reward might enable flies to find previously rewarding locations even without memory. Here, we show that pheromones can indeed cause naïve flies to accumulate where previous flies had been rewarded in a navigation task. Therefore, we designed an experiment to determine if flies can use path integration memory despite potential pheromonal cues by displacing the flies shortly after an optogenetic reward. We found that rewarded flies returned to the location predicted by a memory-based model. Several analyses are consistent with path integration as the mechanism by which flies returned to the reward. We conclude that although pheromones are often important in fly navigation and must be carefully controlled for in future experiments, Drosophila may indeed be capable of performing path integration.
Development and Initial Validation of a Measure to Assess Self-Efficacy to Reduce Sedentary Behavior
Authors: WHIPPLE MARY O. , BERGOUIGNAN AUDREY , HOOKER STEPHANIE A. 
Published: May 2023

ABSTRACT

Introduction
The purpose of this study was to assess the reliability and construct validity of a measure designed to evaluate self-efficacy to reduce sedentary behavior (SB).

Methods
Initial instrument development was based on semistructured interviews and in-depth review of existing measures of self-efficacy for physical activity (PA). Items were drafted by the study authors and reviewed by SB experts. Participants recruited via Amazon Mechanical Turk completed the pool of items and the Exercise Confidence Survey and provided self-reported PA, SB, and demographic information. The sample was divided into two random halves, and exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were performed on each half, respectively. Internal consistency reliability (Cronbach’s alpha) was calculated for the final scale. Initial criterion validity was examined in relation to self-reported SB and PA. Analyses were conducted in SAS 9.4 and Mplus 8.3.

Results
Data were collected from N = 818 adults (47.6% women, mean (standard deviation) age, 37.8 (10.6)). EFA results strongly supported a one-factor scale. Items with low factor loadings (<0.65) were dropped from the scale; 10 items were retained. CFA demonstrated that the 10-item measure fit the data well, but one item had a low factor loading. A final scale with nine items was retained, with good fit to the data (χ
2(27) = 90.79, P < 0.0001, comparative fit statistic = 0.97, root mean square error of approximation = 0.08 [90% confidence interval, 0.06–0.09], standardized root mean square residual = 0.03), and all items had high factor loadings (>0.70). Internal consistency reliability was high (α = 0.91). Self-efficacy to reduce SB was significantly and positively correlated with exercise confidence (r = 0.32–0.38, P < 0.0001).

Conclusions
We developed a nine-item measure of self-efficacy to reduce SB that demonstrates strong initial psychometric properties. Although related to exercise self-efficacy, self-efficacy to reduce SB represents a distinct construct.
Individualized Mental Fatigue Does Not Impact Neuromuscular Function and Exercise Performance
Authors: HOLGADO DARÍAS , JOLIDON LÉO , BORRAGÁN GUILLERMO , SANABRIA DANIEL , PLACE NICOLAS 
Published: May 2023

ABSTRACT

Introduction
Recent studies have questioned previous empirical evidence that mental fatigue negatively impacts physical performance. The purpose of this study was to investigate the critical role of individual differences in mental fatigue susceptibility by analyzing the neurophysiological and physical responses to an individualized mental fatigue task.

Methods
In a preregistered (https://osf.io/xc8nr/), randomized, within-participant design experiment, 22 recreational athletes completed a time to failure test at 80% of their peak power output under mental fatigue (individual mental effort) or control (low mental effort). Before and after the cognitive tasks, subjective feeling of mental fatigue, neuromuscular function of the knee extensors, and corticospinal excitability were measured. Sequential Bayesian analysis until it reached strong evidence in favor of the alternative hypothesis (BF10 > 6) or the null hypothesis (BF10 < 1/6) were conducted.

Results
The individualized mental effort task resulted in a higher subjective feeling of mental fatigue in the mental fatigue condition (0.50 (95% confidence interval (CI), 0.39–0.62)) arbitrary units compared with control (0.19 (95% CI, 0.06–0.339)) arbitrary unit. However, exercise performance was similar in both conditions (control: 410 (95% CI, 357–463) s vs mental fatigue: 422 (95% CI, 367–477) s, BF10 = 0.15). Likewise, mental fatigue did not impair knee extensor maximal force-generating capacity (BF10 = 0.928) and did not change the extent of fatigability or its origin after the cycling exercise.

Conclusions
There is no evidence that mental fatigue adversely affects neuromuscular function or physical exercise; even if mental fatigue is individualized, computerized tasks seem not to affect physical performance.
Humid Heat Equally Impairs Maximal Exercise Performance in Elite Para-Athletes and Able-Bodied Athletes
Authors: Alkemade Puck , de Korte Johannus Q. , Bongers Coen C. W. G. , Daanen Hein A. M. , Hopman Maria T. E. , Janssen Thomas W. J. , Eijsvogels Thijs M. H. 
Published: May 2023

ABSTRACT

Purpose
To compare the impact of hot-humid environmental conditions on performance outcomes, thermoregulatory responses, and thermal perception during exercise between elite para- and able-bodied (AB) athletes.

Methods
20 elite para-athletes (para-cycling and wheelchair tennis) and 20 elite AB athletes (road cycling, mountain biking, beach volleyball) performed an incremental exercise test in a temperate environment (mean ± SD: 15.2 ± 1.2 °C, relative humidity 54 ± 7%) and a hot-humid environment (31.9 ± 1.6 °C, 72 ± 5%). Exercise tests started with a 20-min warm-up at 70% of maximal heart rate, after which power output increased by 5% every 3 min until volitional exhaustion.

Results
Time to exhaustion was shorter in hot-humid versus temperate conditions, with equal performance loss for para- and AB athletes (median [IQR]: 26 [20–31]% vs. 27 [19–32]%; p = 0.80). AB athletes demonstrated larger exercise-induced increases in gastrointestinal temperature (Tgi) in hot-humid versus temperate conditions (2.2 ± 0.7 vs. 1.7 ± 0.5, p < 0.001), whereas Tgi responses in para-athletes were similar between conditions (1.3 ± 0.6 vs. 1.3 ± 0.4, p = 0.74). Para- and AB athletes showed similar elevations in peak skin temperature (p = 0.94), heart rate (p = 0.67), and thermal sensation score (p = 0.64) in hot-humid versus temperate conditions.

Conclusions
Elite para-athletes and AB athletes demonstrated similar performance decrements during exercise in hot-humid versus temperate conditions, whilst Tgi elevations were markedly lower in para-athletes. We observed large inter-individual variation within both groups, suggesting that in both para- and AB athletes, personalized heat mitigation plans should be developed based on individual thermal testing.
Qualitative assessments of density and background parenchymal enhancement on contrast-enhanced spectral mammography associated with breast cancer risk in high-risk women
Authors: Xu Cong , Jiang Meiping , Lin Fan , Zhang Kun , Xie Haizhu , Lv Wei , Ji Haixia , Mao Ning 
Published: May 2023

Objective: To investigate the correlation between the risk of breast cancer for high-risk females and the density and background parenchymal enhancement (BPE) on contrast-enhanced spectral mammography (CESM). Methods: Females at high-risk, without breast cancer history and received CESM from July 2016 to December 2017 were retrospectively enrolled. The longest follow-up time was 4.5 years, and patients who developed breast cancer with maximized follow-up time were classified as cancer cohort, while females who did not develop breast cancer were categorized as control cohort. These two cohorts were one-to-one matched in age, family and/or genetic history of breast cancer, menopausal status and BRCA status. The density and BPE at CESM imaging were assessed. Conditional logistic regression was applied to evaluate the relationship between imaging features and breast cancer risk. Results: During the follow-up interval, 90 women at high-risk without history of breast cancer were newly diagnosed. Compared with minimal BPE, increasing BPE levels were associated with the risk of breast cancer among high-risk females in a time interval of 4.5 years (mild: odds ratio [OR]=3.2, p = 0.001; moderate: OR = 4.0, p = 0.002; marked: OR = 11.2, p < 0.001). In addition, females with mild, moderate or marked BPE were four times more likely to be diagnosed with breast cancer than females with minimal BPE in a time interval of 4.5 years (OR = 4.0, p < 0.001). Conclusion: Qualitative CESM BPE assessment may be useful in the prediction of breast cancer risk among high-risk females. Advances in knowledge: • Qualitative CESM BPE assessment may be useful in the prediction of breast cancer risk among high-risk women during the follow-up period of 4.5 years. • The significance of breast density as an independent risk factor is not fully established for high-risk women during the follow-up period of 4.5 years.
Effects of non-contact electric fields on kidney and liver histology in tumour-induced rats
Authors: Alamsyah Firman , Firdausi Nisrina , Nugraheni Subekti Evi Dwi , Fadhlurrahman Ahmad Ghitha , Nurhidayat Luthfi , Pratiwi Rarastoeti , Taruno Warsito Purwo 
Published: May 2023

Background: A novel modality of cancer treatment based on exposure to non-contact electric fields has been developed to reduce the cancer incidence. However, the safety of this electric field exposure on vital organs has not been fully investigated. Therefore, the purpose of this study was to observe the safety of the electric field exposure on kidney and liver structures. Methods: Female Sprague-Dawley rats were divided into one control group and three treatment groups. Animals were treated with 7,12-dimethylbenz[a]anthracene for mammary tumour induction and exposed to non-contact electric fields individually for 10 hours a day for three weeks. Fresh samples of kidney and liver were collected for observation of structural damage in both organs. Both organs were prepared for histopathological cross-sectioning using the paraffin method and Hematoxylin & Eosin staining followed by histological scoring using the post-examination masking method. Results: Damages found in the kidney were as follows: thickening of Bowman capsule, karyolysis, karyorrexhis, pyknosis, cloudy swelling, epithelial sloughing, inflammation, haemorrhage, and congestion. The thickening of Bowman’s capsule was significant, but other damages to the rest of kidney tissue were not significant. In addition, the number of inflammations and haemorrhages in the kidney structure of the placebo group was the lowest and significantly different compared to the other three groups. All damages to the kidneys were also found in the liver, but each showed a different degree of damage. The damages to the liver caused by exposure to the electric fields were not significant. Conclusions: Together with the effects of DMBA administration, exposure to non-contact electric fields can cause thickening of Bowman's capsule in the glomerulus of the kidney, however, in other kidney tissues and in the liver, exposure to this electric field was safe. It can even decrease the number of inflammations and haemorrhages in the organs.
Obesogenic Environment in the medical field: First year findings from a five-year cohort study
Authors: Andoy-Galvan Jo Ann , Sriram Shyamkumar , Kiat Tey Jin , Xin Lim Zig , Shin Wong Jun , Chinna Karuthan 
Published: May 2023

Background: Doctors with a normal BMI and healthy living habits have shown to be more confident and effective in providing realistic guidance and obesity management to their patient. This study investigated obesogenic tendencies of medical students as they progress in their medical studies. Methods: A cohort of forty-nine medical students enrolled in a five-year cohort study and was followed up after one year. At the initiation of the cohort, socio-demography and information on anthropometry, accommodation, eating behavior, stress and sleeping habits of the students had been recorded. Follow-up data were collected using a standardized self-administered questionnaire. Results: Thirty-seven percent of the students in the cohort are either obese or overweight in the one-year period. A year of follow-up suggests that there is an increase in BMI among the male students (P=0.008) and the changes are associated with changes in accommodation (P=0.016) , stress levels (P=0.021), and sleeping habits (P=0.011). Conclusion: Medical education system should seriously consider evaluating this aspect in the curriculum development to help our future medical practitioners practice a healthy lifestyle and be the initiator of change in the worsening prevalence of obesity worldwide.