Elevated Shear Stress Modulates Heterogenous Cellular Subpopulations to Induce Vascular Remodeling.

Elevated shear stress (ESS) induces vascular remodeling in veins exposed to arterial blood flow, which can lead to arteriovenous (AV) fistula failure. The molecular mechanisms driving remodeling have not been comprehensively examined with a single-cell resolution before. Using an animal mode, single-cell RNA sequencing, and histopathology, we precisely manipulate blood flow to comprehensively characterize all cell subpopulations important during vascular remodeling.

The new European Medical Device Regulation: Friend or foe for hospitals and patients?

The new EU Medical Device Regulation (MDR) was introduced in 2017 to increase the safety and quality of medical devices in the European Union. Theoretically, several hundred thousand medical devices must be approved under the new MDR guidelines, although the majority of these products have been and will be in daily use in countless operations on the European market for decades. The expected expenditure of time and money until the MDR is fully implemented is associated with high costs, patient disadvantages but also manufacturer problems.

Visualizing the Unseen: Illustrating and Documenting Phantom Limb Sensations and Phantom Limb Pain With C.A.L.A.

Currently, there is neither a standardized mode for the documentation of phantom sensations and phantom limb pain, nor for their visualization as perceived by patients. We have therefore created a tool that allows for both, as well as for the quantification of the patient's visible and invisible body image. A first version provides the principal functions: (1) Adapting a 3D avatar for self-identification of the patient; (2) modeling the shape of the phantom limb; (3) adjusting the position of the phantom limb; (4) drawing pain and cramps directly onto the avatar; and (5) quantifying their respective intensities.

Evolution of the AO Spine Sacral and Pelvic Classification System: a systematic review.

Objective: The purpose of this study was to describe the genesis of the AO Spine Sacral and Pelvic Classification System in the context of historical sacral and pelvic grading systems.

Methods: A systematic search of MEDLINE, EMBASE, Google Scholar, and Cochrane databases was performed consistent with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify all existing sacral and pelvic fracture classification systems.

Results: A total of 49 articles were included in this review, comprising 23 pelvic classification systems and 17 sacral grading schemes.

An Overlooked Bone Metabolic Disorder: Cigarette Smoking-Induced Osteoporosis.

Cigarette smoking (CS) leads to significant bone loss, which is recognized as an independent risk factor for osteoporosis. The number of smokers is continuously increasing due to the addictive nature of smoking. Therefore it is of great value to effectively prevent CS-induced osteoporosis.

The prognostic role of extended preoperative hypercoagulability work-up in high-risk microsurgical free flaps: a single-center retrospective case series of patients with heterozygotic factor V Leiden thrombophilia.

Introduction: Hypercoagulability is associated with an increased risk of microvascular complications and free flap failures. The authors present their experience and approach to diagnosing and treating patients with heterozygotic factor V Leiden (hFVL) thrombophilia undergoing free flap reconstruction.

Methods: Between November 2009 and June 2018, 23 free flap surgeries were performed in 15 hypercoagulable patients with hFVL.

Feasibility of a Wireless Implantable Multi-electrode System for High-bandwidth Prosthetic Interfacing: Animal and Cadaver Study.

Background: Currently used prosthetic solutions in upper extremity amputation have limited functionality, owing to low information transfer rates of neuromuscular interfacing. Although surgical innovations have expanded the functional potential of the residual limb, available interfaces are inefficacious in translating this potential into improved prosthetic control. There is currently no implantable solution for functional interfacing in extremity amputation which offers long-term stability, high information transfer rates, and is applicable for all levels of limb loss.

Direct Current Electrical Fields Improve Experimental Wound Healing by Activation of Cytokine Secretion and Erk1/2 Pathway Stimulation.

There is growing evidence that cell behaviors can be influenced by the direct current electric fields (EFs). Some behaviors may influence wound healing directly. This study aimed to investigate the effects of EF (200 mV/mm) on immortalized nontumorigenic human epidermal (HaCaT) cells.

Treatment Trends of Adult Brachial Plexus Injury: A Bibliometric Analysis.

Unlabelled: Brachial plexus injury is often debilitating because it can severely impair upper extremity function and, thus, quality of life. The surgical treatment of injuries to the brachial plexus is very demanding because it requires a profound understanding of the anatomy and expertise in microsurgery. The aim of this study was to get an overview of the landscape in adult brachial plexus injury surgery, and to understand how this has changed over the years.

Late Implant Failure in Cervical Disc Arthroplasty (M6-C, Spinal Kinetics) Causing Radiculopathy and Myelopathy.

Cervical disc arthroplasty (CDA) is an approved surgical treatment option in selected patients with cervical spinal disc degeneration. Even though CDA is a standard procedure since 20 years, there is a lack of information about long term performance. The published reoperation rates after CDA are low and comparable to anterior cervical fusion.

Rehabilitation of high upper limb amputees after Targeted Muscle Reinnervation.

Study Design: This is a Delphi study based on a scoping literature review.

Introduction: Targeted muscle reinnervation (TMR) enables patients with high upper limb amputations to intuitively control a prosthetic arm with up to six independent control signals. Although there is a broad agreement regarding the importance of structured motor learning and prosthetic training after such nerve transfers, to date, no evidence-based protocol for rehabilitation after TMR exists.

Assessment of tobacco heating system 2.4 on osteogenic differentiation of mesenchymal stem cells and primary human osteoblasts compared to conventional cigarettes.

Background: Cigarette smoking (CS) is the most common method of consuming tobacco. Deleterious effects on bone integrity, increased incidence of fractures, and delayed fracture healing are all associated with CS. Over 150 of the 6500 molecular species contained in cigarette smoke and identified as toxic compounds are inhaled by CS and, the bloodstream, reach the skeletal system.

Identification of the Secreted Proteins Originated from Primary Human Hepatocytes and HepG2 Cells.

The liver plays a pivotal role in whole-body carbohydrate, lipid, and protein metabolism. One of the key regulators of glucose and lipid metabolism are hepatokines, which are found among the liver secreted proteins, defined as liver secretome. To elucidate the composition of the human liver secretome and identify hepatokines in primary human hepatocytes (PHH), we conducted comprehensive protein profiling on conditioned medium (CM) of PHH.

Epigenetic Modifications of the Liver Tumor Cell Line HepG2 Increase Their Drug Metabolic Capacity.

Although human liver tumor cells have reduced metabolic functions as compared to primary human hepatocytes (PHH) they are widely used for pre-screening tests of drug metabolism and toxicity. The aim of the present study was to modify liver cancer cell lines in order to improve their drug-metabolizing activities towards PHH. It is well-known that epigenetics is strongly modified in tumor cells and that epigenetic regulators influence the expression and function of Cytochrome P450 (CYP) enzymes through altering crucial transcription factors responsible for drug-metabolizing enzymes.

cGMP-dependent protein kinase I (cGKI) modulates human hepatic stellate cell activation.

Background: The activation of hepatic stellate cells (HSCs) plays a crucial role in liver fibrosis, however the role of HSCs is less understood in hepatic insulin resistance. Since in the liver cGMP-dependent protein kinase I (cGKI) was detected in HSC but not in hepatocytes, and cGKI-deficient mice that express cGKI selectively in smooth muscle but not in other cell types (cGKI-SM mice) displayed hepatic insulin resistance, we hypothesized that cGKI modulates HSC activation and insulin sensitivity.

Materials And Methods: To study stellate cell activation in cGKI-SM mice, retinol storage and gene expression were studied.

Resveratrol protects primary cilia integrity of human mesenchymal stem cells from cigarette smoke to improve osteogenic differentiation in vitro.

Several studies have explored the negative effects of cigarette smoke on bone healing; however, the complex pathogenesis still remains unclear. One crucial and primary factor determining effective fracture repair is the recruitment and differentiation of mesenchymal stem cells (MSCs) into bone-forming cells. Recently, primary cilia, microtubule-based sensory organelles, have been shown to be critical in lineage commitment and differentiation of MSCs.

Engineering the geometrical shape of mesenchymal stromal cells through defined cyclic stretch regimens.

Stem cells have been predicted to improve disease outcomes and patient lives. Steering stem cell fate - through controlling cell shape - may substantially accelerate progress towards this goal. As mesenchymal stromal cells (MSCs) are continuously exposed in vivo to a dynamically changing biomechanical environment, we hypothesized that exogenous forces can be applied for engineering a variety of significantly different MSC shapes.

Human osteoarthritic chondrons outnumber patient- and joint-matched chondrocytes in hydrogel culture-Future application in autologous cell-based OA cartilage repair?

Autologous chondrocyte implantation (ACI) is used in 34-60% for osteoarthritic (OA) cartilage defects, although ACI is neither recommended nor designed for OA. Envisioning a hydrogel-based ACI for OA that uses chondrons instead of classically used chondrocytes, we hypothesized that human OA chondrons may outperform OA chondrocytes. We compared patient- and joint surface-matched human OA chondrons with OA chondrocytes cultured for the first time in a hydrogel, using a self-assembling peptide system.

The geometrical shape of mesenchymal stromal cells measured by quantitative shape descriptors is determined by the stiffness of the biomaterial and by cyclic tensile forces.

Controlling mesenchymal stromal cell (MSC) shape is a novel method for investigating and directing MSC behaviour in vitro. it was hypothesized that specifigc MSC shapes can be generated by using stiffness-defined biomaterial surfaces and by applying cyclic tensile forces. Biomaterials used were thin and thick silicone sheets, fibronectin coating, and compacted collagen type I sheets.

Stretching human mesenchymal stromal cells on stiffness-customized collagen type I generates a smooth muscle marker profile without growth factor addition.

Using matrix elasticity and cyclic stretch have been investigated for inducing mesenchymal stromal cell (MSC) differentiation towards the smooth muscle cell (SMC) lineage but not in combination. We hypothesized that combining lineage-specific stiffness with cyclic stretch would result in a significantly increased expression of SMC markers, compared to non-stretched controls. First, we generated dense collagen type I sheets by mechanically compressing collagen hydrogels.

IL-10 reduces apoptosis and extracellular matrix degradation after injurious compression of mature articular cartilage.

Objective: The aim of this study was to examine whether anti-inflammatory interleukin-10 (IL-10) exerts chondroprotective effects in an in vitro model of a single mechanical injury of mature articular cartilage.

Method: Articular cartilage was harvested from the femoro-patellar groove of adult cows (Bos taurus) and cultured w/o bovine IL-10. After 24 h of equilibration explants were subjected to an axial unconfined compression (50% strain, velocity 2 mm/s, held for 10 s).

Comparison of the Prehospital Trauma Life Support recommendations and the German national guideline on treatment of patients with severe and multiple injuries.

Background: The Prehospital Trauma Life Support (PHTLS) concept is well established throughout the world. The aim is to improve prehospital care for patients with major trauma. In 2011, a German Level 3 (S3) evidence- and consensus-based guideline on the treatment of patients with severe and multiple injuries was published.

Outcome of Radial Head Arthroplasty in Comminuted Radial Head Fractures: Short and Midterm Results.

Background: Comminuted radial head fractures are often associated with secondary injuries and elbow instability.

Objectives: The aim of this retrospective study was to evaluate how well the modular metallic radial head implant EVOLVE® prosthesis restores functional range of motion (ROM) and stability of the elbow in acute care.

Patients And Methods: Eighty-five patients with comminuted radial head fractures and associated injuries received treatment with an EVOLVE® prosthesis between May 2001 and November 2009.

Vitamin C enhances epigenetic modifications induced by 5-azacytidine and cell cycle arrest in the hepatocellular carcinoma cell lines HLE and Huh7.

Background: 5-Azacytidine (5-AZA), a DNA methyl transferase inhibitor, is a clinically used epigenetic drug for cancer therapy. Recently, we have shown that 5-AZA upregulates ten-eleven translocation (TET) protein expression in hepatocellular carcinoma (HCC) cells, which induce active demethylation. Vitamin C facilitates TET activity and enhances active demethylation.