Evolution and biogeography of the endemic Roucela complex (Campanulaceae: Campanula) in the Eastern Mediterranean

At the intersection of geological activity, climatic fluctuations, and human pressure, the Mediterranean Basin – a hotspot of biodiversity – provides an ideal setting for studying endemism, evolution, and biogeography. Here, we focus on the Roucela complex (Campanula subgenus Roucela), a group of 13 bellflower species found primarily in the eastern Mediterranean Basin. Plastid and low‐copy nuclear markers were employed to reconstruct evolutionary relationships and estimate divergence times within the Roucela complex using both concatenation and species tree analyses. Niche modeling, ancestral range estimation, and diversification analyses were conducted to provide further insights into patterns of endemism and diversification through time. Diversification of the Roucela clade appears to have been primarily the result of vicariance driven by the breakup of an ancient landmass. We found geologic events such as the formation of the mid‐Aegean trench and the Messinian Salinity Crisis to be historically important in the evolutionary history of this group. Contrary to numerous past studies, the onset of the Mediterranean climate has not promoted diversification in the Roucela complex and, in fact, may be negatively affecting these species. This study highlights the diversity and complexity of historical processes driving plant evolution in the Mediterranean Basin.     

Analysis of Attentional Bias towards Attractive and Unattractive Body Regions among Overweight Males and Females: An Eye-Movement Study

Background

Body image distortion is highly prevalent among overweight individuals. Whilst there is evidence that body-dissatisfied women and those suffering from disordered eating show a negative attentional bias towards their own unattractive body parts and others’ attractive body parts, little is known about visual attention patterns in the area of obesity and with respect to males. Since eating disorders and obesity share common features in terms of distorted body image and body dissatisfaction, the aim of this study was to examine whether overweight men and women show a similar attentional bias.

Methods/Design

We analyzed eye movements in 30 overweight individuals (18 females) and 28 normal-weight individuals (16 females) with respect to the participants’ own pictures as well as gender- and BMI-matched control pictures (front and back view). Additionally, we assessed body image and disordered eating using validated questionnaires.

Discussion

The overweight sample rated their own body as less attractive and showed a more disturbed body image. Contrary to our assumptions, they focused significantly longer on attractive compared to unattractive regions of both their own and the control body. For one’s own body, this was more pronounced for women. A higher weight status and more frequent body checking predicted attentional bias towards attractive body parts. We found that overweight adults exhibit an unexpected and stable pattern of selective attention, with a distinctive focus on their own attractive body regions despite higher levels of body dissatisfaction. This positive attentional bias may either be an indicator of a more pronounced pattern of attentional avoidance or a self-enhancing strategy. Further research is warranted to clarify these results.     

Simulating soil N2O emissions and heterotrophic CO2 respiration in arable systems using FASSET and MoBiLE-DNDC

Modelling of soil emissions of nitrous oxide (N₂O) and carbon dioxide (CO₂) is complicated by complex interactions between processes and factors influencing their production, consumption and transport. In this study N₂O emissions and heterotrophic CO₂ respiration were simulated from soils under winter wheat grown in three different organic and one inorganic fertilizer-based cropping system using two different models, i.e., MoBiLE-DNDC and FASSET. The two models were generally capable of simulating most seasonal trends of measured soil heterotrophic CO₂ respiration and N₂O emissions. Annual soil heterotrophic CO₂ respiration was underestimated by both models in all systems (about 10?C30% by FASSET and 10?C40% by MoBiLE-DNDC). Both models overestimated annual N₂O emissions in all systems (about 10?C580% by FASSET and 20?C50% by MoBiLE-DNDC). In addition, both models had some problems in simulating soil mineral nitrogen, which seemed to originate from deficiencies in simulating degradation of soil organic matter, incorporated residues of catch crops and organic fertilizers. To improve the performance of the models, organic matter decomposition parameters need to be revised.     

Response properties of visual neurons in the turtle nucleus isthmi

The optic tectum holds a central position in the tectofugal pathway of non-mammalian species and is reciprocally connected with the nucleus isthmi. Here, we recorded from individual nucleus isthmi pars parvocellularis (Ipc) neurons in the turtle eye-attached whole-brain preparation in response to a range of computer-generated visual stimuli. Ipc neurons responded to a variety of moving or flashing stimuli as long as those stimuli were small. When mapped with a moving spot, the excitatory receptive field was of circular Gaussian shape with an average half-width of less than 3°. We found no evidence for directional sensitivity. For moving spots of varying sizes, the measured Ipc response-size profile was reproduced by the linear Difference-of-Gaussian model, which is consistent with the superposition of a narrow excitatory center and an inhibitory surround. Intracellular Ipc recordings revealed a strong inhibitory connection from the nucleus isthmi pars magnocellularis (Imc), which has the anatomical feature to provide a broad inhibitory projection. The recorded Ipc response properties, together with the modulatory role of the Ipc in tectal visual processing, suggest that the columns of Ipc axon terminals in turtle optic tectum bias tectal visual responses to small dark changing features in visual scenes.     

Analysis of historic changes in regional ecosystem service provisioning using land use data

Land use change has a major impact on goods and services that our environment supplies for society. While detailed ecological or biophysical field studies are needed to quantify the exact amount of ecosystem service supply at local scales, such a monitoring might be unfeasible at the regional scale. Since field scale monitoring schemes for ecosystem services or ecosystem functioning are missing, proxy based indicators can help to assess the historic development of ecosystem services or ecosystem functioning at the regional scale. We show at the example of the historic development (1964–2004) in the district of Leipzig/Germany how land use/land cover data can be used to derive regional scale indicators for ecosystem functions. We focus thereby on two hypotheses: (1) the ecosystem functioning has degraded over time and (2) changes in land use configuration play an important role in this degradation. The study focuses on indicators for ecosystem functions related to (i) water purification by riparian buffer strips, (ii) pollination, (iii) food production and (iv) outdoor recreation. Each indicator builds on the analysis of land use configuration and land use composition information and is tested on sensitivity/robustness with respect to parameters which had to be estimated based on expert knowledge. We show that land use composition is an important aspect in our ecosystem service assessment. Although our study region is faced with a maximum land use change of 11% in the major land use classes between 1964 and 2004, we see a decrease of ecosystem function indicators up to 23%. The regional assessment shows an overall trend for degradation of ecosystem functioning from 1964 to 1984. This trend is reversed between 1984 and 1994 but the process slowed down until 2004 without reaching the level of 1964.     

Expression of collier in the premandibular segment of myriapods: support for the traditional Atelocerata concept or a case of convergence?

Background  

A recent study on expression and function of the ortholog of the Drosophila collier (col) gene in various arthropods including insects, crustaceans and chelicerates suggested a de novo function of col in the development of the appendage-less intercalary segment of insects. However, this assumption was made on the background of the now widely-accepted Pancrustacea hypothesis that hexapods represent an in-group of the crustaceans. It was therefore assumed that the expression of col in myriapods would reflect the ancestral state like in crustaceans and chelicerates, i.e. absence from the premandibular/intercalary segment and hence no function in its formation.     

Neuroendocrinology and neurobiology of sebaceous glands

The nervous system communicates with peripheral tissues through nerve fibres and the systemic release of hypothalamic and pituitary neurohormones. Communication between the nervous system and the largest human organ, skin, has traditionally received little attention. In particular, the neuro‐regulation of sebaceous glands (SGs), a major skin appendage, is rarely considered. Yet, it is clear that the SG is under stringent pituitary control, and forms a fascinating, clinically relevant peripheral target organ in which to study the neuroendocrine and neural regulation of epithelia. Sebum, the major secretory product of the SG, is composed of a complex mixture of lipids resulting from the holocrine secretion of specialised epithelial cells (sebocytes). It is indicative of a role of the neuroendocrine system in SG function that excess circulating levels of growth hormone, thyroxine or prolactin result in increased sebum production (seborrhoea). Conversely, growth hormone deficiency, hypothyroidism, and adrenal insufficiency result in reduced sebum production and dry skin. Furthermore, the androgen sensitivity of SGs appears to be under neuroendocrine control, as hypophysectomy (removal of the pituitary) renders SGs largely insensitive to stimulation by testosterone, which is crucial for maintaining SG homeostasis. However, several neurohormones, such as adrenocorticotropic hormone and α‐melanocyte‐stimulating hormone, can stimulate sebum production independently of either the testes or the adrenal glands, further underscoring the importance of neuroendocrine control in SG biology. Moreover, sebocytes synthesise several neurohormones and express their receptors, suggestive of the presence of neuro‐autocrine mechanisms of sebocyte modulation. Aside from the neuroendocrine system, it is conceivable that secretion of neuropeptides and neurotransmitters from cutaneous nerve endings may also act on sebocytes or their progenitors, given that the skin is richly innervated. However, to date, the neural controls of SG development and function remain poorly investigated and incompletely understood. Botulinum toxin‐mediated or facial paresis‐associated reduction of human sebum secretion suggests that cutaneous nerve‐derived substances modulate lipid and inflammatory cytokine synthesis by sebocytes, possibly implicating the nervous system in acne pathogenesis. Additionally, evidence suggests that cutaneous denervation in mice alters the expression of key regulators of SG homeostasis. In this review, we examine the current evidence regarding neuroendocrine and neurobiological regulation of human SG function in physiology and pathology. We further call attention to this line of research as an instructive model for probing and therapeutically manipulating the mechanistic links between the nervous system and mammalian skin.     

Chloroplasts require glutathione reductase to balance reactive oxygen species and maintain efficient photosynthesis

Thiol‐based redox‐regulation is vital for coordinating chloroplast functions depending on illumination and has been throroughly investigated for thioredoxin‐dependent processes. In parallel, glutathione reductase (GR) maintains a highly reduced glutathione pool, enabling glutathione‐mediated redox buffering. Yet, how the redox cascades of the thioredoxin and glutathione redox machineries integrate metabolic regulation and detoxification of reactive oxygen species remains largely unresolved because null mutants of plastid/mitochondrial GR are embryo‐lethal in Arabidopsis thaliana. To investigate whether maintaining a highly reducing stromal glutathione redox potential (E_GSH) via GR is necessary for functional photosynthesis and plant growth, we created knockout lines of the homologous enzyme in the model moss Physcomitrella patens. In these viable mutant lines, we found decreasing photosynthetic performance and plant growth with increasing light intensities, whereas ascorbate and zeaxanthin/antheraxanthin levels were elevated. By in vivo monitoring stromal E_GSH dynamics, we show that stromal E_GSH is highly reducing in wild‐type and clearly responsive to light, whereas an absence of GR leads to a partial glutathione oxidation, which is not rescued by light. By metabolic labelling, we reveal changing protein abundances in the GR knockout plants, pinpointing the adjustment of chloroplast proteostasis and the induction of plastid protein repair and degradation machineries. Our results indicate that the plastid thioredoxin system is not a functional backup for the plastid glutathione redox systems, whereas GR plays a critical role in maintaining efficient photosynthesis.     

S-adenosylmethionine and methylthioadenosine boost cellular productivities of antibody forming Chinese hamster ovary cells

The improvement of cell specific productivities for the formation of therapeutic proteins is an important step towards intensified production processes. Among others, the induction of the desired production phenotype via proper media additives is a feasible solution provided that said compounds adequately trigger metabolic and regulatory programs inside the cells. In this study, S-(5′-adenosyl)- l -methionine (SAM) and 5′-deoxy-5′-(methylthio)adenosine (MTA) were found to stimulate cell specific productivities up to approx. 50% while keeping viable cell densities transiently high and partially arresting the cell cycle in an anti-IL-8-producing CHO-DP12 cell line. Noteworthy, MTA turned out to be the chemical degradation product of the methyl group donor SAM and is consumed by the cells.