215 research outputs found
Anatomical Network Comparison of Human Upper and Lower, Newborn and Adult, and Normal and Abnormal Limbs, with Notes on Development, Pathology and Limb Serial Homology vs. Homoplasy
How do the various anatomical parts (modules) of the animal body evolve into very different integrated forms (integration) yet still function properly without decreasing the individual's survival? This long-standing question remains unanswered for multiple reasons, including lack of consensus about conceptual definitions and approaches, as well as a reasonable bias toward the study of hard tissues over soft tissues. A major difficulty concerns the non-trivial technical hurdles of addressing this problem, specifically the lack of quantitative tools to quantify and compare variation across multiple disparate anatomical parts and tissue types. In this paper we apply for the first time a powerful new quantitative tool, Anatomical Network Analysis (AnNA), to examine and compare in detail the musculoskeletal modularity and integration of normal and abnormal human upper and lower limbs. In contrast to other morphological methods, the strength of AnNA is that it allows efficient and direct empirical comparisons among body parts with even vastly different architectures (e.g. upper and lower limbs) and diverse or complex tissue composition (e.g. bones, cartilages and muscles), by quantifying the spatial organization of these parts-their topological patterns relative to each other-using tools borrowed from network theory. Our results reveal similarities between the skeletal networks of the normal newborn/adult upper limb vs. lower limb, with exception to the shoulder vs. pelvis. However, when muscles are included, the overall musculoskeletal network organization of the upper limb is strikingly different from that of the lower limb, particularly that of the more proximal structures of each limb. Importantly, the obtained data provide further evidence to be added to the vast amount of paleontological, gross anatomical, developmental, molecular and embryological data recently obtained that contradicts the long-standing dogma that the upper and lower limbs are serial homologues. In addition, the AnNA of the limbs of a trisomy 18 human fetus strongly supports Pere Alberch's ill-named "logic of monsters" hypothesis, and contradicts the commonly accepted idea that birth defects often lead to lower integration (i.e. more parcellation) of anatomical structures
Breastfeeding and childhood asthma: a six-year population-based cohort study
<p>Abstract</p> <p>Background</p> <p>The question of the protective effect of breastfeeding on development of asthma has raised substantial interest, but the scientific evidence of the optimal duration of breastfeeding is controversial.</p> <p>Methods</p> <p>The authors elaborated the optimal duration of breastfeeding with respect to the risk of asthma primarily, and secondarily to the risk of persistent wheezing, cough and phlegm in school age in a population-based cohort study with the baseline in 1991 and follow-up in 1997. The study population comprised 1984 children aged 7 to 14 years at the end of the follow-up (follow-up rate 77). Information on breastfeeding was based on the baseline survey and information on the health outcomes at the follow-up.</p> <p>Results</p> <p>There was a U-shaped relation between breastfeeding and the outcomes with the lowest risk with breastfeeding from four to nine months for asthma and seven to nine months for persistent wheezing, cough and phlegm.</p> <p>Conclusion</p> <p>Our results suggest a U shape relation between duration of breastfeeding and risk of asthma with an optimal duration of 4 to 6 months. A true concave relation would explain the inconsistent results from the previous studies.</p
Nut production in Bertholletia excelsa across a logged forest mosaic: implications for multiple forest use
Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world’s most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1–2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich forests, when a buffer zone cannot be observed, low logging intensities should be implemented. The sustainability of this integrated management system will ultimately depend on a complex series of socioeconomic and ecological interactions. Yet we submit that our study provides an important initial step in understanding the compatibility of timber harvesting with a high value NTFP, potentially allowing for diversification of forest use strategies in Amazonian Perù
Cultural Transmission of Traditional Knowledge in two populations of North-western Patagonia
<p>Abstract</p> <p>Background</p> <p>In the present study we have investigated the cultural transmission of two types of traditional plant knowledge in two communities of North-western Patagonia, Argentina. In the Pilcaniyeu community, we studied the transmission of traditional knowledge related to horticultural practices in home-gardens, greenhouses and gardens; while in the community of Cuyin Manzano, we studied wild plant gathering customs.</p> <p>Methods</p> <p>Ethnobotanical fieldwork was conducted by means of semi-structured interviews, in which we investigated which plants are used, at what life history phase was learned, modes of transmission and who the principal transmitters were in childhood and adulthood. In both communities, each of this three aspects related to cultural transmission were categorized and the frequencies of each category were obtained. The total number of species recorded in each community was also calculated. Frequencies were analyzed with the Chi-square test of independence.</p> <p>Results and discussion</p> <p>In both communities, transmission of traditional plant knowledge begins at an early age, as a family custom, in which women play a predominant role. Wild plant use and horticultural knowledge continue to be learned during adulthood. This was particularly registered associated with horticultural learning, which receives greater influence from extension agents who are introducing new practices and technology. This outside influence, which implies novelty, could imply syncretism but also traditional knowledge loss.</p> <p>Conclusion</p> <p>Given the remarkable acculturation processes occurring at present in rural communities of Northwestern Patagonia, it might be of vital importance to document traditional knowledge of ancient practices. Moreover, it could be interesting to share our results with both populations in order to encourage participatory activities within the communities which could enhance traditional knowledge horizontal transmission, particularly among elder adults and youngsters.</p
Conscientiousness, Career Success, and Longevity: A Lifespan Analysis
Markers of executive functioning, such as prudent planning for the future and impulse control, are related to conscientiousness and may be central to both occupational success and health outcomes.
The aim of the study was to examine relations among conscientiousness, career success, and mortality risk across a 65-year period.
Using data derived from 693 male participants in the Terman Life Cycle Study, we examined associations among childhood personality, midlife objective career success, and lifelong mortality risk through 2006.
Conscientiousness and career success each predicted lower mortality risk (N = 693, relative hazard (rh) = 0.82 [95% confidence interval = 0.74, 0.91] and rh = 0.80 [0.71, 0.91], respectively), with both shared and unique variance. Importantly, childhood personality moderated the success–longevity link; conscientiousness was most relevant for least successful individuals.
Conscientiousness and career success predicted longevity, but not in a straightforward manner. Findings highlight the importance of lifespan processes
Involvement of EphB1 Receptors Signalling in Models of Inflammatory and Neuropathic Pain
EphB receptors tyrosine kinases and ephrinB ligands were first identified as guidance molecules involved in the establishment of topographical mapping and connectivity in the nervous system during development. Later in development and into adulthood their primary role would switch from guidance to activity-dependent modulation of synaptic efficacy. In sensory systems, they play a role in both the onset of inflammatory and neuropathic pain, and in the establishment of central sensitisation, an NMDA-mediated form of synaptic plasticity thought to underlie most forms of chronic pain. We studied wild type and EphB1 knockout mice in a range of inflammatory and neuropathic pain models to determine 1), whether EphB1 expression is necessary for the onset and/or maintenance of persistent pain, regardless of origin; 2), whether in these models cellular and molecular changes, e.g. phosphorylation of the NR2B subunit of the NMDA receptor, increased c-fos expression or microglial activation, associated with the onset of pain, are affected by the lack of functional EphB1 receptors. Differences in phenotype were examined behaviourally, anatomically, biochemically and electrophysiologically. Our results establish firstly, that functional EphB1 receptors are not essential for the development of normal nociception, thermal or mechanical sensitivity. Secondly, they demonstrate a widespread involvement of EphB1 receptors in chronic pain. NR2B phosphorylation, c-fos expression and microglial activation are all reduced in EphB1 knockout mice. This last finding is intriguing, since microglial activation is supposedly triggered directly by primary afferents, therefore it was not expected to be affected. Interestingly, in some models of long-term pain (days), mechanical and thermal hyperalgesia develop both in wild type and EphB1 knockout mice, but recovery is faster in the latter, indicating that in particular models these receptors are required for the maintenance, rather than the onset of, thermal and mechanical hypersensitivity. This potentially makes them an attractive target for analgesic strategies
Primary brain calcification: an international study reporting novel variants and associated phenotypes.
Primary familial brain calcification (PFBC) is a rare cerebral microvascular calcifying disorder with a wide spectrum of motor, cognitive, and neuropsychiatric symptoms. It is typically inherited as an autosomal-dominant trait with four causative genes identified so far: SLC20A2, PDGFRB, PDGFB, and XPR1. Our study aimed at screening the coding regions of these genes in a series of 177 unrelated probands that fulfilled the diagnostic criteria for primary brain calcification regardless of their family history. Sequence variants were classified as pathogenic, likely pathogenic, or of uncertain significance (VUS), based on the ACMG-AMP recommendations. We identified 45 probands (25.4%) carrying either pathogenic or likely pathogenic variants (n = 34, 19.2%) or VUS (n = 11, 6.2%). SLC20A2 provided the highest contribution (16.9%), followed by XPR1 and PDGFB (3.4% each), and PDGFRB (1.7%). A total of 81.5% of carriers were symptomatic and the most recurrent symptoms were parkinsonism, cognitive impairment, and psychiatric disturbances (52.3%, 40.9%, and 38.6% of symptomatic individuals, respectively), with a wide range of age at onset (from childhood to 81 years). While the pathogenic and likely pathogenic variants identified in this study can be used for genetic counseling, the VUS will require additional evidence, such as recurrence in unrelated patients, in order to be classified as pathogenic
Metabolism-dependent bioaccumulation of uranium by Rhodosporidium toruloides isolated from the flooding water of a former uranium mine
Remediation of former uranium mining sites represents one of the biggest challenges worldwide
that have to be solved in this century. During the last years, the search of alternative
strategies involving environmentally sustainable treatments has started. Bioremediation,
the use of microorganisms to clean up polluted sites in the environment, is considered one
the best alternative. By means of culture-dependent methods, we isolated an indigenous
yeast strain, KS5 (Rhodosporidium toruloides), directly from the flooding water of a former
uranium mining site and investigated its interactions with uranium. Our results highlight
distinct adaptive mechanisms towards high uranium concentrations on the one hand, and
complex interaction mechanisms on the other. The cells of the strain KS5 exhibit high a
uranium tolerance, being able to grow at 6 mM, and also a high ability to accumulate this
radionuclide (350 mg uranium/g dry biomass, 48 h). The removal of uranium by KS5 displays
a temperature- and cell viability-dependent process, indicating that metabolic activity
could be involved. By STEM (scanning transmission electron microscopy) investigations,
we observed that uranium was removed by two mechanisms, active bioaccumulation and
inactive biosorption. This study highlights the potential of KS5 as a representative of indigenous
species within the flooding water of a former uranium mine, which may play a key role
in bioremediation of uranium contaminated sites.This work was supported by the
Bundesministerium für Bildung und Forschung
grand nº 02NUK030F (TransAqua). Further support
took place by the ERDF-co-financed Grants
CGL2012-36505 and 315 CGL2014-59616R,
Ministerio de Ciencia e Innovación, Spain
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