The topography of the superficial veins of the hind leg in the baboon Papio anubis in comparison with the superficial veins of the lower limb in humans

Our studies were carried out on 8 male and 2 female baboons Papio anubis cadavers. We examined a total of 20 hind legs. The vessels of the hind leg were filled with coloured latex. Afterwards we prepared the superficial and deep veins and accompanying arteries. We paid attention to the location, diameter and the course of the long and short saphenous veins. We found many differences between the system of superficial veins in the baboon hind leg and that in the human lower limb. First of all, the long saphenous vein in the baboon Papio anubis presented as two similar trunks that ran together with a concomitant artery. The saphenofemoral junction was also duplicated. The distance between these outlets was about 4 mm and their location was different from that in humans. Neither trunk exceeded 2.5 m in diameter. Some human-like features were noticed in the system of the short saphenous vein in Papio anubis. The diameter of the short saphenous vein and its course and the location of the saphenopopliteal junction were very similar to those in humans. On the other hand, the short saphenous vein was the main superficial venous channel of the hind limb of Papio anubis

The effect of tantalum on the structure/properties of two polycrystalline nickel-base superalloys: B-1900 + Hf MAR-M247

The microstructure, phase compositions, and phase fractions were studied in conventionally cast B-1900 + Hf and both conventionally cast and directionally solidified MAR-M247 as a function of tantalum concentration. The hot tensile and creep rupture properties of the solutionized and aged MAR-M247-type alloys were also determined as a function of tantalum level. The effects of tantalum on the microstructure and phase compositions of B-1900 + Hf and MAR-M247 (conventionally cast and directionally solidified) were found to be very similar. The addition of tantalum to the as cast and heat treated alloys was shown to cause the partial replacement of the Hf in the MC carbides by Ta, although the degree of replacement was decreased by the solutionizing and aging heat treatment. The gamma prime and minor phase fractions (primarily MC type carbides) both increased approximately linearly with tantalum concentration. The gamma prime phase compositions were relatively insensitive to tantalum variations with the exception of the tantalum and/or hafnium levels. Bulk tantalum additions increased the tantalum, chromium, and cobalt levels of the gamma phase in both alloy series. The increase in the concentrations of the latter two elements in the gamma phase was a result of the decrease in the gamma phase fraction with increasing bulk tantalum concentration and constant gamma/gamma prime partitioning ratio. Tantalum additions increased the yield stress and ultimate tensile strength of the directionally solidified MAR-M247 type alloys and had no significant effect on ductility

Changes in the wall of the great saphenous vein at consecutive stages in patients suffering from chronic vein disease of the lower limbs

The aim of the study was to show the changes in the great saphenous vein (GSV) wall at consecutive stages in the development of chronic vein disease (CVD) in patients qualified for a surgical procedure after physical examination and Doppler ultrasonography. Four groups of patients were formed (C2, C3, C4 and C5/6) according to clinical stage of the CEAP classification (C - clinical signs, E - aetiopathology, A - anatomy and P - pathophysiology). After the surgical procedure for removal of the varicose GSVs, 40 segments were harvested from their proximal parts near the saphenofemoral junction, 10 segments for each CEAP group. The veins were sectioned transversally and stained with the resorcin-fuchsin and AZAN method to visualise the elastic end collagen fibres. Afterwards the specimens were analysed under an optical microscope and photographed. As the GSV is an elastic vessel and its wall is divided into three zones, namely the internal layer (intima), the medial layer (media) and the external layer (adventitia), we found a proliferation of the connective tissue among the smooth muscle cells inside the internal and medial layers at consecutive stages of CVD. The later stages of CVD also revealed a larger number of the elastic and collagen fibres inside the intima and media and a looser arrangement of the smooth muscle cells of the media in the GSV wall

Poverty and the rural non-farm economy in Armenia, Georgia and Romania: a synthesis of findings (NRI report no. 2773)

The focus of this paper is on rural non-farm livelihoods in economies in transition. It looks at key factors affecting the ability and motivation of rural dwellers to become involved in the non-farm economy. The intended outputs of this study are: (i) to improve understanding of the dynamics of the RNFE in providing employment and income diversification opportunities in Armenia, Georgia and Romania; and (ii) to promote mechanisms for integrating research results into relevant policy processes

Improved chemistry restraints for crystallographic refinement by integrating the Amber force field into Phenix.

The refinement of biomolecular crystallographic models relies on geometric restraints to help to address the paucity of experimental data typical in these experiments. Limitations in these restraints can degrade the quality of the resulting atomic models. Here, an integration of the full all-atom Amber molecular-dynamics force field into Phenix crystallographic refinement is presented, which enables more complete modeling of biomolecular chemistry. The advantages of the force field include a carefully derived set of torsion-angle potentials, an extensive and flexible set of atom types, Lennard-Jones treatment of nonbonded interactions and a full treatment of crystalline electrostatics. The new combined method was tested against conventional geometry restraints for over 22 000 protein structures. Structures refined with the new method show substantially improved model quality. On average, Ramachandran and rotamer scores are somewhat better, clashscores and MolProbity scores are significantly improved, and the modeling of electrostatics leads to structures that exhibit more, and more correct, hydrogen bonds than those refined using traditional geometry restraints. In general it is found that model improvements are greatest at lower resolutions, prompting plans to add the Amber target function to real-space refinement for use in electron cryo-microscopy. This work opens the door to the future development of more advanced applications such as Amber-based ensemble refinement, quantum-mechanical representation of active sites and improved geometric restraints for simulated annealing

Cell-based therapies for stroke : promising solution or dead end?

The introduction of recanalization procedures has revolutionized acute stroke management, although the narrow time window, strict eligibility criteria and logistical limitations still exclude the majority of patients from treatment. In addition, residual deficits are present in many patients who undergo therapy, preventing their return to premorbid status. Hence, there is a strong need for novel, and ideally complementary, approaches to stroke management. In preclinical experiments, cell-based treatments have demonstrated beneficial effects in the subacute and chronic stages following stroke [1; 2; 3] and therefore are considered a promising option to supplement current clinical practice. At the same time, great progress has been made in developing clinically feasible delivery and monitoring protocols [4]. However, efficacy results initially reported in clinical studies fell short of expectations [5] raising concerns that cell treatment might eventually share the ‘dead end fate’ of many previous experimental stroke therapies. This Research Topic reviews some of the latest and most innovative studies to summarize the state of the art in translational cell treatments for stroke

Human bone marrow mesenchymal stem cell-derived extracellular vesicles attenuate neuroinflammation evoked by focal brain injury in rats

Background Ischemic stroke is the major cause of long-term severe disability and death in aged population. Cell death in the infarcted region of the brain induces immune reaction leading to further progression of tissue damage. Immunomodulatory function of mesenchymal stem cells (MSCs) has been shown in multiple preclinical studies; however, it has not been successfully translated to a routine clinical practice due to logistical, economical, regulatory, and intellectual property obstacles. It has been recently demonstrated that therapeutic effect of intravenously administered MSCs can be recapitulated by extracellular vesicles (EVs) derived from them. However, in contrast to MSCs, EVs were not capable to decrease stroke-induced neuroinflammation. Therefore, the aim of the study was to investigate if intra-arterial delivery of MSC-derived EVs will have stronger impact on focal brain injury-induced neuroinflammation, which mimics ischemic stroke, and how it compares to MSCs. Methods The studies were performed in adult male Wistar rats with focal brain injury induced by injection of 1 mu l of 50 nmol ouabain into the right hemisphere. Two days after brain insult, 5 x 10(5) human bone marrow MSCs (hBM-MSCs) labeled with Molday ION or 1.3 x 10(9) EVs stained with PKH26 were intra-arterially injected into the right hemisphere under real-time MRI guidance. At days 1, 3, and 7 post-transplantation, the rats were decapitated, the brains were removed, and the presence of donor cells or EVs was analyzed. The cellular immune response in host brain was evaluated immunohistochemically, and humoral factors were measured by multiplex immunoassay. Results hBM-MSCs and EVs transplanted intra-arterially were observed in the rat ipsilateral hemisphere, near the ischemic region. Immunohistochemical analysis of brain tissue showed that injection of hBM-MSCs or EVs leads to the decrease of cell activation by ischemic injury, i.e., astrocytes, microglia, and infiltrating leucocytes, including T cytotoxic cells. Furthermore, we observed significant decrease of pro-inflammatory cytokines and chemokines after hBM-MSC or EV infusion comparing with non-treated rats with focal brain injury. Conclusions Intra-arterially injected EVs attenuated neuroinflammation evoked by focal brain injury, which mimics ischemic stroke, and this effect was comparable to intra-arterial hBM-MSC transplantation. Thus, intra-arterial injection of EVs might be an attractive therapeutic approach, which obviates MSC-related obstacles