16 research outputs found
Systemic neurotransmitter responses to clinically approved and experimental neuropsychiatric drugs.
Neuropsychiatric disorders are the third leading cause of global disease burden. Current pharmacological treatment for these disorders is inadequate, with often insufficient efficacy and undesirable side effects. One reason for this is that the links between molecular drug action and neurobehavioral drug effects are elusive. We use a big data approach from the neurotransmitter response patterns of 258 different neuropsychiatric drugs in rats to address this question. Data from experiments comprising 110,674 rats are presented in the Syphad database [ www.syphad.org ]. Chemoinformatics analyses of the neurotransmitter responses suggest a mismatch between the current classification of neuropsychiatric drugs and spatiotemporal neurostransmitter response patterns at the systems level. In contrast, predicted drug-target interactions reflect more appropriately brain region related neurotransmitter response. In conclusion the neurobiological mechanism of neuropsychiatric drugs are not well reflected by their current classification or their chemical similarity, but can be better captured by molecular drug-target interactions
Management and prevention of acute bleedings in the head and neck area with interventional radiology
Engineering of vascularized adipose constructs
Adipose tissue engineering offers a promising alternative to the current surgical techniques for the treatment of soft tissue defects. It is a challenge to find the appropriate scaffold that not only represents a suitable environment for cells but also allows fabrication of customized tissue constructs, particularly in breast surgery. We investigated two different scaffolds for their potential use in adipose tissue regeneration. Sponge-like polyurethane scaffolds were prepared by mold casting with methylal as foaming agent, whereas polycaprolactone scaffolds with highly regular stacked-fiber architecture were fabricated with fused deposition modeling. Both scaffold types were seeded with human adipose tissuederived precursor cells, cultured and implanted in nude mice using a femoral arteriovenous flow-through vessel loop for angiogenesis. In vitro, cells attached to both scaffolds and differentiated into adipocytes. In vivo, angiogenesis and adipose tissue formation were observed throughout both constructs after 2 and 4 weeks, with angiogenesis being comparable in seeded and unseeded constructs. Fibrous tissue formation and adipogenesis were more pronounced on polyurethane foam scaffolds than on polycaprolactone prototyped scaffolds. In conclusion, both scaffold designs can be effectively used for adipose tissue engineering
Prefabrication of 3D cartilage contructs: towards a tissue engineered auricle--a model tested in rabbits.
The reconstruction of an auricle for congenital deformity or following trauma remains one of the greatest challenges in reconstructive surgery. Tissue-engineered (TE) three-dimensional (3D) cartilage constructs have proven to be a promising option, but problems remain with regard to cell vitality in large cell constructs. The supply of nutrients and oxygen is limited because cultured cartilage is not vascular integrated due to missing perichondrium. The consequence is necrosis and thus a loss of form stability. The micro-surgical implantation of an arteriovenous loop represents a reliable technology for neovascularization, and thus vascular integration, of three-dimensional (3D) cultivated cell constructs. Auricular cartilage biopsies were obtained from 15 rabbits and seeded in 3D scaffolds made from polycaprolactone-based polyurethane in the shape and size of a human auricle. These cartilage cell constructs were implanted subcutaneously into a skin flap (15 × 8 cm) and neovascularized by means of vascular loops implanted micro-surgically. They were then totally enhanced as 3D tissue and freely re-implanted in-situ through microsurgery. Neovascularization in the prefabricated flap and cultured cartilage construct was analyzed by microangiography. After explantation, the specimens were examined by histological and immunohistochemical methods. Cultivated 3D cartilage cell constructs with implanted vascular pedicle promoted the formation of engineered cartilaginous tissue within the scaffold in vivo. The auricles contained cartilage-specific extracellular matrix (ECM) components, such as GAGs and collagen even in the center oft the constructs. In contrast, in cultivated 3D cartilage cell constructs without vascular pedicle, ECM distribution was only detectable on the surface compared to constructs with vascular pedicle. We demonstrated, that the 3D flaps could be freely transplanted. On a microangiographic level it was evident that all the skin flaps and the implanted cultivated constructs were well neovascularized. The presented method is suggested as a promising alternative towards clinical application of engineered cartilaginous tissue for plastic and reconstructive surgery
Cytotoxic and genotoxic effects of resin monomers in human salivary gland tissue and lymphocytes as assessed by the single cell microgel electrophoresis (Comet) assay
Malignant tumors of the three major pairs and the numerous minor salivary glands in humans are rare, and little is known about their various etiologies. Considering the fact that resin monomers from dental restorative materials are released into the saliva and diffuse into the tooth pulp or gingiva, mucosa, and salivary glands, this may potentially contribute to tumorigenesis. Resin monomers may also be reabsorbed and reach the circulating blood as well. Whereas the cytotoxic potential of some components has been clearly documented, data on genotoxicity in human target cells require further investigation. In the present study, genotoxic and cytotoxic effects of three common methacrylates are investigated in human samples of salivary glands and peripheral lymphocytes. The Comet assay was used to quantify DNA single strand breaks, alkali labile and incomplete excision repair sites in salivary gland probes and lymphocytes of 10 volunteers. The xenobiotics investigated were triethyleneglycoldimethacrylate (TEGDMA), urethanedimethacrylate (UDMA), and 2-hydroxyethylmethacrylate (HEMA), with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and dimethyl sulfoxide (DMSO) as controls. DNA migration was analyzed using the tail moment according to Olive (OTM). Cytotoxicity was monitored using trypan blue staining. With TEGDMA concentrations at 10(-5)m (10(-3)m), UDMA at 10(-7)m (10(-7)m), and HEMA at 10(-3)m (10(-5)m) significant enhancements of DNA migration were achieved in tissue cells (lymphocytes) as compared to the negative controls. At higher concentrations of up to 2.5x10(-2)m, induced DNA migration was expressed by OTM at 10.7 for TEGDMA in tissue cells (8.7 in lymphocytes), 10.5 for UDMA (6.4), and 9.7 for HEMA (6.1). The viability of the cell systems was not affected as concerns the threshold level for the assay of 75% viable cells except for the highest concentration tested for TEGDMA and UDMA in tissue cells. At higher concentration levels, all tested substances induced significant enhancement of DNA migration in the Comet assay as a possible sign for genotoxic effects in human salivary glands and lymphocytes. These data add to the results of prior studies in human peripheral lymphocytes and give evidence of a possible risk factor for tumor initiation in human salivary glands
Histological results.
<p>A (study group): Stitched full cross section of the cultured auricle (black+white line). B: Implanted vascular pedicle (saphenous artery and greater saphenous vein), original magnification, x5. C+E: Low power view of the center of the cultivated cartilage cell biomaterial construct shows GAG, black arrows indicate ingrown vessels (C: Alcian blue counterstained with Kernechtred, original magnification, x50; E: Alcian blue staining, original magnification, x50). D+F: Periphery of cultivated cartilage cell biomaterial construct shows vital cartilage and good integration in the skin flap. White arrow indicates an ingrown vessel (Alcian blue counterstained with Kernechtred, original magnification, D×10; C×200). G (control group): Stitched full cross section of the cultured auricle (black+white line). H+J: Low power view of the center of the cultivated cartilage cell biomaterial construct shows necrosis with no GAG (H: Alcian blue counterstained with Kernechtred, original magnification, ×50; J: Alcian blue staining, original magnification, ×50). I+K: Periphery of cultivated cartilage cell biomaterial construct shows small areas of vital cartilage and good integration in the skin flap. (Alcian blue counterstained with Kernechtred, original magnification, I×10, K×200). L: Image indicates the performed sectional planes within the biomaterial construct. All showed histological images are from section plane E. Scale bars = 400 µm.</p
Biomaterial construct prior to implantation.
<p>A: Polyurethane based polycaprolactone construct seeded with chondrocytes. B: SEM picture of porous PCL construct, magnification 48×. C: Live/dead staining was performed with fluoresceindiacetate and propidium jodid using confocal laser scanning microscopy. D: Cultivated cartilage cell biomaterial construct (black arrow) implanted subcutaneously above the panniculus carnosus; day 0 postoperative. Scale bars = 1 cm.</p
Harvesting of cartilage, cell culture, and seeding of biomaterials.
<p>The auricular cartilage biopsies were weighed prior to cell isolation after thorough cleaning and sectioning. After cell isolation cell number was determined. After amplification cell number was increased 676× after passage two or three. There were no significant differences between test and control group; p = 0.881 (weight of cartilage biopsy), p = 0.766 (cells isolated), p = 0.655 (amplificated cell number); Mann-Whitney Test (two-tailed).</p
Surgical procedures.
<p>A: The implantation of the cultured auricle (white arrow) took place on the right side of the abdomen above the panniculus carnosus in a skin flap measuring 150×80 mm. A silicon foil was sewn onto the abdominal fascia to prevent neovascularization from the abdominal wall. Saphenous artery and greater saphenous vein were distally anastomosed turned in the cranial direction and attached below the abdominal skin flap. *indicates the original position of A. saphena and V. saphena magna. B: Four-sided flap excision. To proof the ability of the neovascularized cultivated 3D cartilage cell construct (black arrow) to survive solely perfused by the newly implanted axial vascular pedicle the abdominal flap was excised four-sided, leaving the vascular pedicle (white arrow) intact. C: Macroscopic view after free microsurgical transplantation. Healed skin flap three weeks after free microsurgical transplantation. Black arrow indicates the integrated neovascularized cultured auricle. Scale bars = 5 cm.</p
Angiographically quantified neovascularization in prefabricated 3D flaps. This boxplot shows the quantitative neovascularization of the 10 test flaps in comparison to 6 native abdominal skin flaps (control). To quantify the neovascularization in prefabricated 3D flaps 25 evenly spaced standard integral lines were placed corresponding to the 15-cm flap length. Vessel quantity was determined by counting the total number of times that vessels perfused by Micropaque ® intersected the integral lines over the entire surface of the flap under 2× magnification as described previously [14]. There was a significant difference between experimental and control group, ***p = 0.0002, Mann-Whitney Test (two-tailed).
<p>Angiographically quantified neovascularization in prefabricated 3D flaps. This boxplot shows the quantitative neovascularization of the 10 test flaps in comparison to 6 native abdominal skin flaps (control). To quantify the neovascularization in prefabricated 3D flaps 25 evenly spaced standard integral lines were placed corresponding to the 15-cm flap length. Vessel quantity was determined by counting the total number of times that vessels perfused by Micropaque ® intersected the integral lines over the entire surface of the flap under 2× magnification as described previously <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0071667#pone.0071667-Hoang2" target="_blank">[14]</a>. There was a significant difference between experimental and control group, ***p = 0.0002, Mann-Whitney Test (two-tailed).</p