72 research outputs found
The insect nephrocyte is a podocyte-like cell with a filtration slit diaphragm.
The nephron is the basic structural and functional unit of the vertebrate kidney. It is composed of a glomerulus, the site of ultrafiltration, and a renal tubule, along which the filtrate is modified. Although widely regarded as a vertebrate adaptation, 'nephron-like' features can be found in the excretory systems of many invertebrates, raising the possibility that components of the vertebrate excretory system were inherited from their invertebrate ancestors. Here we show that the insect nephrocyte has remarkable anatomical, molecular and functional similarity to the glomerular podocyte, a cell in the vertebrate kidney that forms the main size-selective barrier as blood is ultrafiltered to make urine. In particular, both cell types possess a specialized filtration diaphragm, known as the slit diaphragm in podocytes or the nephrocyte diaphragm in nephrocytes. We find that fly (Drosophila melanogaster) orthologues of the major constituents of the slit diaphragm, including nephrin, NEPH1 (also known as KIRREL), CD2AP, ZO-1 (TJP1) and podocin, are expressed in the nephrocyte and form a complex of interacting proteins that closely mirrors the vertebrate slit diaphragm complex. Furthermore, we find that the nephrocyte diaphragm is completely lost in flies lacking the orthologues of nephrin or NEPH1-a phenotype resembling loss of the slit diaphragm in the absence of either nephrin (as in human congenital nephrotic syndrome of the Finnish type, NPHS1) or NEPH1. These changes markedly impair filtration function in the nephrocyte. The similarities we describe between invertebrate nephrocytes and vertebrate podocytes provide evidence suggesting that the two cell types are evolutionarily related, and establish the nephrocyte as a simple model in which to study podocyte biology and podocyte-associated diseases.This work was supported by Wellcome Trust
grants awarded to H.S. (072441 and 079221, H.W., B.D., H.S.); Deutsche Forschungsgemeinschaft (SFB 590) awarded
to Elisabeth Knust (F.G.), ARC 1242 (H.W., B.D., H.S., F.G.); MEC grant awarded to M.R-G. (BFU2007-62201,
S.P-S., M.R-G.); Fundación Ramón Areces grant to the CBMSO (M.R-G.); EC grant LSHG-CT-2004-511978 to
MYORES (M.R-G.); an FPU fellowship from the MEC awarded to A.G-L.Peer reviewe
Processing unit resources in a distributed computing systems
The described program is designed for collecting, storing and processing data of distributed file system
Diverse Applications of Nanomedicine
The design and use of materials in the nanoscale size range for addressing medical and health-related issues continues to receive increasing interest. Research in nanomedicine spans a multitude of areas, including drug delivery, vaccine development, antibacterial, diagnosis and imaging tools, wearable devices, implants, high-throughput screening platforms, etc. using biological, nonbiological, biomimetic, or hybrid materials. Many of these developments are starting to be translated into viable clinical products. Here, we provide an overview of recent developments in nanomedicine and highlight the current challenges and upcoming opportunities for the field and translation to the clinic. \ua9 2017 American Chemical Society
Bioartificial heart: a human-sized porcine model - the way ahead
BACKGROUND: A bioartificial heart is a theoretical alternative to transplantation or mechanical left ventricular support. Native hearts decellularized with preserved architecture and vasculature may provide an acellular tissue platform for organ regeneration. We sought to develop a tissue-engineered whole-heart neoscaffold in human-sized porcine hearts. METHODS: We decellularized porcine hearts (n = 10) by coronary perfusion with ionic detergents in a modified Langendorff circuit. We confirmed decellularization by histology, transmission electron microscopy and fluorescence microscopy, quantified residual DNA by spectrophotometry, and evaluated biomechanical stability with ex-vivo left-ventricular pressure/volume studies, all compared to controls. We then mounted the decellularized porcine hearts in a bioreactor and reseeded them with murine neonatal cardiac cells and human umbilical cord derived endothelial cells (HUVEC) under simulated physiological conditions. RESULTS: Decellularized hearts lacked intracellular components but retained specific collagen fibers, proteoglycan, elastin and mechanical integrity; quantitative DNA analysis demonstrated a significant reduction of DNA compared to controls (82.6+/-3.2 ng DNA/mg tissue vs. 473.2+/-13.4 ng DNA/mg tissue, p<0.05). Recellularized porcine whole-heart neoscaffolds demonstrated re-endothelialization of coronary vasculature and measurable intrinsic myocardial electrical activity at 10 days, with perfused organ culture maintained for up to 3 weeks. CONCLUSIONS: Human-sized decellularized porcine hearts provide a promising tissue-engineering platform that may lead to future clinical strategies in the treatment of heart failure
Winkelstabile Platte zur Behandlung der Insuffizienzfrakturen des Beckens („minimally invasive posterior locked compression plate“)
Zusammenfassung
Operationsziel
Belastungsstabile Versorgung des Beckenringes mit hoher Primärstabilität.
Indikation
Instabilität und ausbleibende Mobilisierbarkeit bei osteoporotischen Beckenbrüchen.
Kontraindikationen
Dekubitalgeschwüre, Infekte.
Operationstechnik
Minimal-invasive winkelstabile Versorgung durch 4,5 LCP (locked compression plate, DePuy Synthes, Zuchwil, Schweiz) von dorsal.
Weiterbehandlung
Sofortige Mobilisation mit Vollbelastung, Röntgenverlaufskontrolle.
Evidenz
Die Nachuntersuchung eines Kollektivs von 34 Patienten zeigte keine Implantatlockerungen sowie eine vergleichsweise niedrige Strahlenexposition.
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Minimally invasive posterior locked compression plate osteosynthesis shows excellent results in elderly patients with fragility fractures of the pelvis
Purpose!#!Fragility fractures of the pelvis (FFP) are common in older patients. We evaluated the clinical outcome of using a minimally invasive posterior locked compression plate (MIPLCP) as therapeutic alternative.!##!Methods!#!53 Patients with insufficiency fractures of the posterior pelvic ring were treated with MIPLCP when suffering from persistent pain and immobility under conservative treatment. After initial X-ray, CT-scans of the pelvis were performed. In some cases an MRI was also performed to detect occult fractures. Postoperatively patients underwent conventional X-ray controls. Data were retrospectively analyzed for surgical and radiation time, complication rate, clinical outcome and compared to the literature.!##!Results!#!Patients (average age 79.1 years) underwent surgery with operation time of 52.3 min (SD 13.9), intra-operative X-ray time of 9.42 s (SD 9.6), mean dose length product of 70.1 mGycm (SD 57.9) and a mean hospital stay of 21.2 days (SD 7.7). 13% patients (n = 7) showed surgery-related complications, such as wound infection, prolonged wound secretion, irritation of the sacral root or clinically inapparent screw malpositioning. 17% (n = 9) showed postoperative complications (one patient died due to pneumonia 24 days after surgery, eight patients developed urinal tract infections). 42 patients managed to return to previous living situation. 34 were followed-up after a mean period of 31.5 (6-90) months and pain level at post-hospital examination of 2.4 (VAS) with an IOWA Pelvic Score of 85.6 (55-99).!##!Conclusion!#!We showed that MIPLCP osteosynthesis is a safe surgical alternative in patients with FFP 3 and FFP 4. This treatment is another way of maintaining a high level of stability in the osteoporotic pelvic ring with a relatively low complication rate, low radiation and moderate operation time and a good functional outcome
Minimally invasive posterior locked compression plate osteosynthesis shows excellent results in elderly patients with fragility fractures of the pelvis
Abstract
Purpose
Fragility fractures of the pelvis (FFP) are common in older patients. We evaluated the clinical outcome of using a minimally invasive posterior locked compression plate (MIPLCP) as therapeutic alternative.
Methods
53 Patients with insufficiency fractures of the posterior pelvic ring were treated with MIPLCP when suffering from persistent pain and immobility under conservative treatment.
After initial X-ray, CT-scans of the pelvis were performed. In some cases an MRI was also performed to detect occult fractures. Postoperatively patients underwent conventional X-ray controls. Data were retrospectively analyzed for surgical and radiation time, complication rate, clinical outcome and compared to the literature.
Results
Patients (average age 79.1 years) underwent surgery with operation time of 52.3 min (SD 13.9), intra-operative X-ray time of 9.42 s (SD 9.6), mean dose length product of 70.1 mGycm (SD 57.9) and a mean hospital stay of 21.2 days (SD 7.7).
13% patients (n = 7) showed surgery-related complications, such as wound infection, prolonged wound secretion, irritation of the sacral root or clinically inapparent screw malpositioning. 17% (n = 9) showed postoperative complications (one patient died due to pneumonia 24 days after surgery, eight patients developed urinal tract infections).
42 patients managed to return to previous living situation. 34 were followed-up after a mean period of 31.5 (6–90) months and pain level at post-hospital examination of 2.4 (VAS) with an IOWA Pelvic Score of 85.6 (55–99).
Conclusion
We showed that MIPLCP osteosynthesis is a safe surgical alternative in patients with FFP 3 and FFP 4. This treatment is another way of maintaining a high level of stability in the osteoporotic pelvic ring with a relatively low complication rate, low radiation and moderate operation time and a good functional outcome.
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