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Groundwater arsenic contamination in the Bengal Delta Plain is an important public health issue
(2021)
There is a close association between human biology, epidemiology and public health. Exposure to toxic elements is one area of such associations and global concerns. The Bengal Delta Plain (BDP) is a region where contamination of ground water by arsenic has assumed epidemic proportions. Apart from dermatological manifestations, chronic exposure to arsenic causes a heavy toll through several carcinogenic and non-carcinogenic disorders. This article provides a global overview of groundwater arsenic contamination in the BDP region, especially the sources, speciation, and mobility of arsenic, and critically reviews the effects of arsenic on human health. The present review also provides a summary of comprehensive knowledge on various measures required for mitigation and social consequences of the problem of arsenic contaminated groundwater in the BDP region.
Background
Subjective Social Status is used as an important predictor for psychological and physiological findings, most commonly measured with the MacArthur Scale (Ladder Test). Previous studies have shown that this test fits better in Western cultures. The idea of a social ladder itself and ranking oneself “higher” or “lower” is a concept that accords to the Western thinking.
Objectives
We hypothesize that in a culture where only the elites have adapted to a Western lifestyle, the test results reflect a higher level of accuracy for this stratum. We also expect that self-perception differs per sex.
Sample and Methods
We implemented the Ladder Test in a study of Indonesian schoolchildren aged between 5 and 13 years (boys N = 369, girls N= 364) from non-private and private schools in Kupang in 2020.
Results
Our analysis showed that the Ladder Test results were according to the Western expectations only for the private school, as the Ladder Scores significantly decreased with age (LM: p = 0.04). The Ladder Test results are best explained by “Education Father” for the non-private school pupils (p = 0.01) and all boys (p = 0.04), by “School Grades” for the private school cohort (p = 0.06) and by “Household Score” for girls (p =0.09).
Conclusion
This finding indicates that the concept of ranking oneself “high” or “low” on a social ladder is strongly implicated with Western ideas. A ladder implies social movement by “climbing” up or down. According to that, reflection of self-perception is influenced by culture.
Background
Over the last 20 years, a decreasing trend in external skeletal robusticity and an increasing trend in overweight and obesity was observed worldwide in adults and children as modern lifestyles in nutritional and activity behavior have changed. However, body mass index (BMI) as a measure for overweight is not an ideal predictor of % body fat (%BF) either in children and adolescents or in adults. On the contrary, it disguises a phenomenon called “hidden obesity”.
Objectives
We aim to approximate %BF by combining skeletal robusticity and BMI and develop an estimation-based tool to identify normal weight obese children and adolescents.
Sample and Methods
We analyzed cross-sectional data on height, weight, elbow breadth, and skinfold thickness (triceps and subscapular) of German children aged 6 to 18 years (N=15,034). We used modified Hattori charts and multiple linear regression to develop a tool, the “%BF estimator”, to estimate %BF by using BMI and skeletal robusticity measured as Frame Index.
Results
Independent of sex and age an increase in BMI is associated with an increase in %BF, an increase in Frame Index is associated with a decrease in %BF. The developed tool “%BF estimator” allows the estimation of %BF per sex and age group after calculation of BMI and Frame Index.
Conclusion
The “%BF estimator” is an easily applicable tool for the estimation of %BF in respect of body composition for clinical practice, screening, and public health research. It is non-invasive and has high accuracy. Further, it allows the identification of normal weight obese children and adolescents.
Background
Nicotine consumption during pregnancy and advanced maternal age are well known independent risk factors for poor pregnancy outcome and therefore serious public health problems.
Objectives
Considering the ongoing trend of delaying childbirth in our society, this study investigates potential additive effects of nicotine consumption during pregnancy and advanced maternal age on foetal growth.
Sample and Methods
In a medical record-based study, we analysed the impact of maternal age and smoking behaviour before and during pregnancy on newborn size among 4142 singleton births that took place in Vienna, Austria between 1990 and 1995.
Results
Birth weight (H=82.176, p<0.001), birth length (H=91.525, p<0.001) and head circumference (H=42.097, p<0.001) differed significantly according to maternal smoking behaviour. For birth weight, the adjusted mean differences between smokers and non-smokers increased from 101.8g for the < 18-year-old mothers to 254.8g for >35 year olds, with the respective values for birth length being 0.6 cm to 0.7cm, for head circumference from 0.3 cm to 0.6 cm.
Conclusion
Increasing maternal age amplified the negative effects of smoking during pregnancy on newborn parameters. Our findings identify older smoking mothers as a high-risk group which should be of special interest for public health systems.
Background
There is a recurring and seamless interaction between the biology of human development and the social-economic-political-emotional (SEPE) environment. The SEPE environment influences the quality of the material conditions for human biology and, simultaneously, human growth in height and other dimensions provide social and moral signals that provide information to community networks.
Objectives
This article reviews the role of SEPE factors in human growth, especially skeletal growth.
Sample and Methods
The meaning of SEPE is defined and shown to be related to individual and group prestige, to social identity, and to ego and task motivation. These influence dominance or subordination of communities and the material and moral conditions of societies. Historical and contemporary examples of SEPE effects on skeletal size are presented.
Results
Membership in a SEPE community impacts skeletal size in height and breadth. Higher SEPE classes are taller, lower SEPE classes are broader. In elite level sport the winners have more growth stimulation via the hormone IGF-1 even before the contest. These findings are explained in terms of dominance versus subordination and the Community Effect in Height hypothesis.
Conclusions
SEPE factor regulation of human growth is shown to be a more comprehensive explanation for plasticity in height than traditional concepts such as socioeconomic status and simple-minded genetic determinism. People belonging to upper SEPE class communities, the elites, know that they are superior and are treated as such by the non-elites. The material and moral condition for life operating through these community social networks provide positive stimulation for the elites and negative stimulation for the lower SEPE classes. These differences maintain the gradients in height between SEPE communities in human societies.
Settings Perspective
(2021)
Water-deficits can cause lethal damage to organisms, which is rooted in cellular dehydration. Many plant species, but also other organisms have developed mechanisms to tolerate such stresses, such as the expression of LEA proteins. Many studies report on physiological protective functions of LEA proteins but lack information about their precise mechanisms on a molecular level. Most LEA proteins are intrinsically disordered in dilute solution but may adopt a distinct secondary structure upon changes in solvent conditions. Understanding the molecular mechanism of how LEA proteins contribute to the counteraction of cellular damage during water-deficits may in the long-term pave the way for breeding crops that are resistant to the effects of global warming. The objective of the work at hand is to improve the biophysical understanding of the sequencestructure-function relationship of LEA proteins as membrane stabilizers, based on the LEA_4 family of the model plant A. thaliana. This is pursued by using a combination of spectroscopic and scattering techniques, supported by bioinformatics and computational analyses. Eight out of the 18 LEA_4 proteins are experimentally assessed revealing that a coil-helix transition in response to water-deficit is a common feature, as predicted for the entire family. In addition, they all stabilize simple membrane models during a freeze/ thaw cycle. Three-dimensional structure prediction of representative members suggests that their completely folded states are represented by a sequential arrangement of alpha-helical segments connected by unstructured linkers, which is experimentally verified for the LEA_4 protein COR15A. The unstructured linker region of COR15A represents a conserved motif among its closest homologs and is, therefore, of particular interest. Facilitating a set of seven designed and investigated COR15A mutants uncovers a complex interplay of transient interactions between the amphipathic alpha-helical segments, mediated by the linker, which fine-tunes folding transitions and structural ensembles upon reduced water-availability. Finally, alpha-helicity is also induced in COR15A upon temperature decrease, which is enhanced in the presence of osmolytes. In addition, high solution osmolarity induced secondary structure is followed by oligomerization of COR15A. Interestingly, the functionality of COR15A, in terms of liposome stabilization, strongly correlates with its alpha-helix ratio in the folded state. The present work significantly improves the understanding of the sequence-structure-function relationship for LEA_4 proteins and offers novel findings on folding mechanisms and oligomerization of COR15A.
Due to global climate change providing food security for an increasing world population is a big challenge. Especially abiotic stressors have a strong negative effect on crop yield. To develop climate-adapted crops a comprehensive understanding of molecular alterations in the response of varying levels of environmental stresses is required. High throughput or ‘omics’ technologies can help to identify key-regulators and pathways of abiotic stress responses. In addition to obtain omics data also tools and statistical analyses need to be designed and evaluated to get reliable biological results.
To address these issues, I have conducted three different studies covering two omics technologies. In the first study, I used transcriptomic data from the two polymorphic Arabidopsis thaliana accessions, namely Col-0 and N14, to evaluate seven computational tools for their ability to map and quantify Illumina single-end reads. Between 92% and 99% of the reads were mapped against the reference sequence. The raw count distributions obtained from the different tools were highly correlated. Performing a differential gene expression analysis between plants exposed to 20 °C or 4°C (cold acclimation), a large pairwise overlap between the mappers was obtained. In the second study, I obtained transcript data from ten different Oryza sativa (rice) cultivars by PacBio Isoform sequencing that can capture full-length transcripts. De novo reference transcriptomes were reconstructed resulting in 38,900 to 54,500 high-quality isoforms per cultivar. Isoforms were collapsed to reduce sequence redundancy and evaluated, e.g. for protein completeness level (BUSCO), transcript length, and number of unique transcripts per gene loci. For the heat and drought tolerant aus cultivar N22, I identified around 650 unique and novel transcripts of which 56 were significantly differentially expressed in developing seeds during combined drought and heat stress. In the last study, I measured and analyzed the changes in metabolite profiles of eight rice cultivars exposed to high night temperature (HNT) stress and grown during the dry and wet season on the field in the Philippines. Season-specific changes in metabolite levels, as well as for agronomic parameters, were identified and metabolic pathways causing a yield decline at HNT conditions suggested.
In conclusion, the comparison of mapper performances can help plant scientists to decide on the right tool for their data. The de novo reconstruction of rice cultivars without a genome sequence provides a targeted, cost-efficient approach to identify novel genes responding to stress conditions for any organism. With the metabolomics approach for HNT stress in rice, I identified stress and season-specific metabolites which might be used as molecular markers for crop improvement in the future.
Transitory starch granules result from complex carbon turnover and display specific situations during starch synthesis and degradation. The fundamental mechanisms that specify starch granule characteristics, such as granule size, morphology, and the number per chloroplast, are largely unknown. However, transitory starch is found in the various cells of the leaves of Arabidopsis thaliana, but comparative analyses are lacking. Here, we adopted a fast method of laser confocal scanning microscopy to analyze the starch granules in a series of Arabidopsis mutants with altered starch metabolism. This allowed us to separately analyze the starch particles in the mesophyll and in guard cells. In all mutants, the guard cells were always found to contain more but smaller plastidial starch granules than mesophyll cells. The morphological properties of the starch granules, however, were indiscernible or identical in both types of leaf cells.
Transitory starch granules result from complex carbon turnover and display specific situations during starch synthesis and degradation. The fundamental mechanisms that specify starch granule characteristics, such as granule size, morphology, and the number per chloroplast, are largely unknown. However, transitory starch is found in the various cells of the leaves of Arabidopsis thaliana, but comparative analyses are lacking. Here, we adopted a fast method of laser confocal scanning microscopy to analyze the starch granules in a series of Arabidopsis mutants with altered starch metabolism. This allowed us to separately analyze the starch particles in the mesophyll and in guard cells. In all mutants, the guard cells were always found to contain more but smaller plastidial starch granules than mesophyll cells. The morphological properties of the starch granules, however, were indiscernible or identical in both types of leaf cells.