The glomerulus – a view from the inside – the endothelial cell

The glomerular endothelial cells are unique both in location and anatomy compared to most other endothelial cells throughout the body. The absence of a diaphragm with retention of a basement membrane and fenestrations enable these uniquely situated cells to have a key role in filtration performed by the kidney. Interaction with other glomerular cells such as the podocytes and mesangial cells, as well as with circulating and infiltrating inflammatory cells, contribute to the final impact of the glomerular endothelial cells on maintenance of body fluid homeostasis and modulation of disease. Thus, endothelial cells contribute to hemodynamic function, reactive oxygen stress, regulate the balance between pro-thrombotic and anti-thrombotic forces, and importantly, contribute to fibrosis, the key injury of progressive chronic kidney disease. Repair of endothelial cell damage and restoration of segmentally sclerosed glomeruli are key areas considered for intervention in chronic kidney disease. This review will focus on the structure, function, and interplay of endothelial cells with other glomerular cells and systemic factors, their impact on renal disease and give rationale for possible intervention that may forestall progressive injuries.     

Metallophytes—a view from the rhizosphere

Abundance of Fabaceae declines in representation through post-fire-succession in fynbos vegetation of the Cape Floristic Region (CFR). This reduction in legume occurrence coincides with a known decline in post-fire soil P availability. It was hypothesized that the disappearance of legume species during post-fire succession is due to an inability to acquire P effectively from sparingly soluble sources. P-acquisition strategies and response to P supply were compared between legume (Aspalathus, Cyclopia, Indigofera, Podalyria) and non-legume (Elegia, Leucadendron, Protea) genera when supplied with 1 or 10 mg P kg^?1 dry sand. Each genus consisted of a seeder (non-persistent) and resprouter (persistent) species. Non-legumes showed a greater investment in below-ground biomass, more root clusters, with higher concentrations of carboxylates exuded by cluster roots and carboxylates that were better suited to the mobilization of sparingly soluble P compared to legumes. The growth response to increased P supply was 53% higher in legumes than in non-legumes. The lack of a growth response to an elevated P supply in the non-legumes was attributed to N-limitation. Legume resprouters had a higher investment in cluster-root biomass and a lower capacity to down-regulate P-uptake than the seeders. Therefore the inability to acquire sufficient P from low concentration and sparingly soluble soil P-sources may contribute to the lack of indigenous legume persistence in fynbos vegetation of the CFR.     

“Always on the outside looking in.” A view of the 1969 Ethiopian elections from a rural constituency.*

Robert Paine's writings about the practice of state tutelage and the genesis of aboriginal peoples’ ethnopolitical strategies vis‐a‐vis the nation‐state have made signal contributions to anthropological understandings of “fourth world” relations. Nevertheless, it should not be assumed that the processes by which contemporary claims of aboriginality are being articulated are unproblematic in their consequences. In Canada, at least, there is reason to question whether the emerging ethnopolitics of aboriginality may not serve to maintain rather than to eliminate some crucial aspects of the subjection of aboriginal people to systems of state‐controlled tutetage.     

Wnts as morphogens? The view from the wing of Drosophila

Morphogens are diffusible signalling molecules that pattern cellular fields by setting up differential gene expression in a concentration-dependent manner. Members of the Wnt family of signalling molecules are generally considered to be classical morphogens. However, a close analysis of their activity indicates that they do not fulfil all of the critera that are associated with the classical definition.     

Cooperative strategies outside the laboratory — evidence from a long-term large-N-study in five countries

Research on human cooperation as an evolutionary adaptation is largely based on results from the laboratory, e.g. public goods games. However, it is debated whether these results of human cooperative behavior extend beyond such settings and whether they are valid in other contexts. Critical issues include the absence of context, the very short period of play and possible observer effects. This article presents data from an alternative controlled, but context-rich setting – a public goods game in an online browser game – with around 18,000 players from five countries over a period of ten months without observer effects. This article focuses on the robustness of previous findings about cooperative strategies and whether different types of cooperative behavior extend beyond the laboratory setting. Thus, the data presented provides external validity to existing laboratory experiments. The results suggest some important qualifications to previous work, since less high cooperators and a differing proportion of conditional cooperation are found. However, this data confirms the reported proportion of free riders at about 25% of the population. Cooperative strategies appear to be stable over time, individually fixed and rather independent of environmental parameters.     

Is the shoot a root with a view?

Recently, it has been shown that the same sets of genes act in both root and shoot to regulate cell fate and patterning. One gene cassette regulates epidermal cell fate, another cassette regulates ground tissue derived cell fate and organization. Ectopic expression and laser ablation have been used to probe the mechanisms by which these genes perform their tissue and organ-specific functions.     

Angioleiomyosarcoma – a very rare malignant tumour from the soft tissue

In the article we describe a case of a 12-year old boy with the tumour in the small pelvis. The only one abnormality in laboratory tests was a 3-numeral ESR and a big solid tumour probably extended from the urine bowel, found on radiological examination. On surgery the tumour was found to extend from the ascendent colon. On pathological examination, it was described as angioleiomyosarcoma with metastases in the lymph nodes. The boy was treated with IX courses consisting of ifosfamide, vepeside or ifosfamide, adriamycine and vincristine. At present, the child is in the first complete remission, 7 months after completion chemotherapy.     

Chromatin states and nuclear organization in development — a view from the nuclear lamina

The spatial distribution of chromatin domains in interphase nuclei changes dramatically during development in multicellular organisms. A crucial question is whether nuclear organization is a cause or a result of differentiation. Genetic perturbation of lamina–heterochromatin interactions is helping to reveal the cross-talk between chromatin states and nuclear organization.     

Revisiting the question of Neandertal regional variability: a view from the Rhône valley corridor

We compared the dental assemblage of the Rh?ne Valley corridor (RVC) with that of European Neandertals dating to MOIS 7-4 using two linear measurements and three indices. To test if the RVC population was significantly different from Western European Neandertals, we preformed a multi-tiered approached. First, we tested for the normality of the variables using a Shapiro-Wilks test. If the variables were normal, a stepwise Discriminant Function Analysis (DFA) (using Mahalanobis distances) was performed for the normally distributed variables. DFA uses correlation metrics to address weight combinations of variables and emphasizes between group variation while minimizing within group variation. Results show that there is no distinction between the RVC population and other Neandertals except for the Crown Module index of the upper canine. However, the presence of a single significant result does not provide evidence for a local RVC variant within the Neandertal population. These results are supported by evidence from archaeological analysis of this region. We propose that the high genetic control for dental size and shape may account for the reduced ability to distinguish between subpopulation groups based on dental dimensions in groups with small effective size such as the Neandertals.     

The world from a cat’s perspective – statistics of natural videos

The mammalian visual system is one of the most intensively investigated sensory systems. However, our knowledge of the typical input it is operating on is surprisingly limited. To address this issue, we seek to learn about the natural visual environment and the world as seen by a cat. With a CCD camera attached to their head, cats explore several outdoor environments and videos of natural stimuli are recorded from the animals perspective. The statistical analysis of these videos reveals several remarkable properties. First, we find an anisotropy of oriented contours with an enhanced occurrence of horizontal orientations, earlier described in the oblique effect as a predominance of the two cardinal orientations. Second, contrast is not elevated in the center of the images, suggesting different mechanisms of fixation point selection as compared to humans. Third, analyzing a sequence of images we find that the precise position of contours varies faster than their orientation. Finally, collinear contours prevail over parallel shifted contours, matching recent physiological and anatomical results. These findings demonstrate the rich structure of natural visual stimuli and its direct relation to extensively studied anatomical and physiological issues.     

“Connecting worlds – a view on microfluidics for a wider application”

From its birth, microfluidics has been referenced as a revolutionary technology and the solution to long standing technological and sociological issues, such as detection of dilute compounds and personalized healthcare. Microfluidics has for example been envisioned as: (1) being capable of miniaturizing industrial production plants, thereby increasing their automation and operational safety at low cost; (2) being able to identify rare diseases by running bioanalytics directly on the patient’s skin; (3) allowing health diagnostics in point-of-care sites through cheap lab-on-a-chip devices. However, the current state of microfluidics, although technologically advanced, has so far failed to reach the originally promised widespread use.In this paper, some of the aspects are identified and discussed that have prevented microfluidics from reaching its full potential, especially in the chemical engineering and biotechnology fields, focusing mainly on the specialization on a single target of most microfluidic devices and offering a perspective on the alternate, multi-use, “plug and play” approach. Increasing the flexibility of microfluidic platforms, by increasing their compatibility with different substrates, reactions and operation conditions, and other microfluidic systems is indeed of surmount importance and current academic and industrial approaches to modular microfluidics are presented. Furthermore, two views on the commercialization of plug-and-play microfluidics systems, leading towards improved acceptance and more widespread use, are introduced. A brief review of the main materials and fabrication strategies used in these fields, is also presented. Finally, a step-wise guide towards the development of microfluidic systems is introduced with special focus on the integration of sensors in microfluidics. The proposed guidelines are then applied for the development of two different example platforms, and to three examples taken from literature.With this work, we aim to provide an interesting perspective on the field of microfluidics when applied to chemical engineering and biotechnology studies, as well as to contribute with potential solutions to some of its current challenges.     

Hepatic stem cells: from inside and outside the liver?

The liver is normally proliferatively quiescent, but hepatocyte loss through partial hepatectomy, uncomplicated by virus infection or inflammation, invokes a rapid regenerative response from all cell types in the liver to perfectly restore liver mass. Moreover, hepatocyte transplants in animals have shown that a certain proportion of hepatocytes in foetal and adult liver can clonally expand, suggesting that hepatoblasts/hepatocytes are themselves the functional stem cells of the liver. More severe liver injury can activate a potential stem cell compartment located within the intrahepatic biliary tree, giving rise to cords of bipotential transit amplifying cells (oval cells), that can ultimately differentiate into hepatocytes and biliary epithelial cells. A third population of stem cells with hepatic potential resides in the bone marrow; these haematopoietic stem cells may contribute to the albeit low renewal rate of hepatocytes, but can make a more significant contribution to regeneration under a very strong positive selection pressure. In such instances, cell fusion rather than transdifferentiation appears to be the underlying mechanism by which the haematopoietic genome becomes reprogrammed.     

Richness and endemism in Asclepiadoideae (Apocynaceae) from the Espinhaço Range of Minas Gerais, Brazil – a conservationist view

The Espinhaço Range, located in the states of Minas Gerais andBahia, has a type of vegetation with one of the highest degrees of endemism inBrazil: the campos rupestres. In this area, Asclepiadoideaeis among the most diverse angiosperm groups, including species with broaddistributions and others restricted to small areas. This study attempts toevaluate the species richness and the degree of endemism in this region, as wellas the influence of collecting efforts on the perception of biodiversity. It isbased especially on the Asclepiadoideae from the Espinhaço Range of MinasGerais (ERMG), though a brief consideration of the situation in Bahia is alsointroduced. For comparative studies, the ERMG was divided into four regions:South, Serra do Cipó, Diamantina Plateau, and North. The species werethen characterized according to their distribution and occurrence in each ofthese regions. Ninety-seven species of Asclepiadoideae are native to the ERMG;about 30% of them are endemic to this area and almost 25% are restricted to onlyone of the four regions. The Serra do Cipó and the Diamantina Plateaupresent the highest degrees of endemism, and the highest richness innumber of species is found in the South. Nevertheless, there is a progressive decrease in collectingefforts northwards, which may distort species distribution and occurrence, andlead to misinterpretations about centers of diversity and endemism. TheEspinhaço Range should be considered vulnerable in its entirety becauseof the singular flora still incompletely known and the restricted distributionof many species. Programs that establish priority areas of conservation withoutconsidering the region as a whole will only offer temporary, partial protectionfor its biodiversity.     

The effects of stenting on coronary endothelium from a molecular biological view: Time for improvement?

Coronary artery stenting following balloon angioplasty represents the gold standard in revascularization of coronary artery stenoses. However, stent deployment as well as percutaneous transluminal coronary angioplasty (PTCA) alone causes severe injury of vascular endothelium. The damaged endothelium is intrinsically repaired by locally derived endothelial cells and by circulating endothelial progenitor cells from the blood, leading to re‐population of the denuded regions within several weeks to months. However, the process of re‐endothelialization is often incomplete or dysfunctional, promoting in‐stent thrombosis and restenosis. The molecular and biomechanical mechanisms that influence the process of re‐endothelialization in stented segments are incompletely understood. Once the endothelium is restored, endothelial function might still be impaired. Several strategies have been followed to improve endothelial function after coronary stenting. In this review, the effects of stenting on coronary endothelium are outlined and current and future strategies to improve endothelial function after stent deployment are discussed.     

A nature reserve as a repository of genetic richness – The case of European larch from the Gorce Mountains

Conservation of valuable populations must be based on a thorough understanding of their genetic variation, especially for species negatively affected by human activities. We investigated the population of larch from the nature reserve in the Gorce Mountains, which was established to preserve a unique stand of Larix decidua subsp. polonica, a remnant of one of the largest native complexes of this species. The chloroplast marker ll-TaqI was used to investigate whether the gene pool of the analysed population was contaminated with the alien larch species. We used eleven nuclear DNA microsatellite markers (nSSRs) to examine this population’s genetic diversity and verify the hypothesis about historical use of the larch from the reserve as a source of reproductive material for the Tatra Mountains. The link between the reserve population and the European larch’s ancestral groups was also verified. No contamination of the studied pool of individuals by alien species was found. The study showed high genetic variability in larch from the Gorce Mountains (H_E = 0.689, H_O = 0.671). The differentiation between the Gorce and Tatra National Park populations was F_ST = 0.038 (p < 0.001). Trees from the reserve and the national park formed two distinct genetic groups. We rejected the hypothesis that the nature reserve was the source of the regeneration material used in the Tatra Mountains. The study proved the uniqueness of the reserve population, and confirmed the appropriateness of the protection measures taken.     

Food purchases: Impacts from the consumers’ point of view investigated with a modular LCA

The goal of this research work was to assist consumers in considering environmental aspects of food consumption. A simplified, modular LCA approach has been used to evaluate the impacts from the consumers’ point of view. Comparative LCA’s have been calculated for five single aspects of decisions: type of agricultural practice, origin, packaging material, type of preservation, and consumption. The inventory for one module includes the environmental impacts related to one particular product characteristic. The modular LCA allows one to investigate the trade-offs among different decision parameters. It could be shown that most of the decision parameters might have an influence on the overall impact of a vegetable product. Greenhouse production and vegetables transported by air cause the highest surplus environmental impact. For meat products, the agricultural production determines the overall environmental impact. The total impact for vegetable or meat purchases may vary by a factor of eight or two-and-a-half. Different suggestions for consumers have been ranked according to the variation of average impacts, due to a marginal change of behaviour. Avoiding air-transported food products leads to the highest decrease of environmental impacts.