Tensile Properties of 21-6-9 Austenitic Stainless Steel Built Using Laser Powder-Bed Fusion.

Alloy 21-6-9 is an austenitic stainless steel with high strength, thermal stability at high temperatures, and retained toughness at cryogenic temperatures. This type of steel has been used for aerospace applications for decades, using traditional manufacturing processes. However, limited research has been conducted on this alloy manufactured using laser powder-bed fusion (LPBF). Therefore, in this work, a design of experiment (DOE) was performed to obtain optimized process parameters with regard to low porosity. Once the optimized parameters were established, horizontal and vertical blanks were built to investigate the mechanical properties and potential anisotropic behavior. As this alloy is exposed to elevated temperatures in industrial applications, the effect of elevated temperatures (room temperature and 750 °C) on the tensile properties was investigated. In this work, it was shown that alloy 21-6-9 could be built successfully using LPBF, with good properties and a density of 99.7%, having an ultimate tensile strength of 825 MPa, with an elongation of 41%, and without any significant anisotropic behavior.

Needle Fasciotomy or Collagenase Injection in the Treatment of Dupuytren's Contracture: A Retrospective Study.

Dupuytren's contracture is common among older people in Sweden. Previous studies comparing the treatment with an injection of collagenase with percutaneous needle fasciotomy found no differences. METHODS: We retrospectively compared the degree of improvement in the deficit in extension of the joints in 2 groups of patients who had been treated with collagenase (71 fingers) or needle fasciotomy (109 fingers) before and 1 year after treatment. We compared the improvement of the extension deficit among the metacarpophalangeal (MCP) and proximal interphalangeal joints before and after the intervention; additionally, the level of improvement was classified into 3 levels (mild = 0° to 29°; moderate = 30° to 60°; considerable = 61° and more). RESULTS: The degree of improvement of extension in the MCP joints was 11° greater in the collagenase group (P = 0.001). The number of patients who had an improvement of >60° (considerable) in extension was greater in the collagenase group (P = 0.02). CONCLUSION: Collagenase was more effective than needle fasciotomy in treating extension deficits of the MCP joints in Dupuytren's contracture in this retrospective analysis. Further prospective studies are required to confirm the finding.

Functional outcome in 17 patients whose mandibles were reconstructed with free fibular flaps.

OBJECTIVE: The vascularised free fibular flap is considered to be a reliable choice for reconstruction of oromandibular defects, especially after resection of malignant tumours in the area. This study evaluates the functional outcome of this method. METHOD: From January 2001 - May 2014, 37 patients were treated at the University Hospital of Linköping using the free fibular flap. The authors present the results from 17. This study reviewed their records and used the University of Washington Quality-of-Life questionnaire (UW-QoL), the Head and Neck Performance Status Scale (PSS), and interviews to assess their outcome. RESULTS AND CONCLUSIONS: Functional evaluation showed a significant decrease in chewing (16 out of 17 patients), appearance (n = 10), salivation (n = 6), sensitivity in the mouth and skin (n = 16), occlusive problems in the mouth (n = 13), and range of mouth opening (n = 12). The remaining domains showed acceptable results, although most of them probably could not compare with the preoperative function. Out of 17 patients, six had to adjust their eating in public significantly, three thought their activity to be considerably restricted and two their recreation to be notably diminished. Common postoperative complications were infections or fistula in the mandible (n = 6), partial or complete rejection of the cutaneous flap (n = 4), and rupture of some of the sutures (n = 3). Nine patients required at least one more operation to repair defects, and six required a new soft tissue flap.

Discovery of indazole ethers as novel, potent, non-steroidal glucocorticoid receptor modulators.

A structure-based design approach led to the identification of a novel class of indazole ether based, non-steroidal glucocorticoid receptor (GR) modulators. Several examples were identified that displayed cell potency in the picomolar range, inhibiting LPS-induced TNF-α release by primary peripheral blood mononuclear cells (PBMCs). Additionally, an improved steroid hormone receptor binding selectivity profile, compared to classical steroidal GR agonists, was demonstrated. The indazole ether core tolerated a broad range of substituents allowing for modulation of the physiochemical parameters. A small sub-set of indazole ethers, with pharmacokinetic properties suitable for oral administration, was investigated in a rat antigen-induced joint inflammation model and demonstrated excellent anti-inflammatory efficacy.

Identification of indole inhibitors of human hematopoietic prostaglandin D2 synthase (hH-PGDS).

Human H-PGDS has shown promise as a potential target for anti-allergic and anti-inflammatory drugs. Here we describe the discovery of a novel class of indole inhibitors, identified through focused screening of 42,000 compounds and evaluated using a series of hit validation assays that included fluorescence polarization binding, 1D NMR, ITC and chromogenic enzymatic assays. Compounds with low nanomolar potency, favorable physico-chemical properties and inhibitory activity in human mast cells have been identified. In addition, our studies suggest that the active site of hH-PGDS can accommodate larger structural diversity than previously thought, such as the introduction of polar groups in the inner part of the binding pocket.

Osteogenically-induced human dermal fibroblasts as a tool to regenerate bone.

Engineering of bone tissue could help to overcome the need for extensive reconstruction and associated donor site morbidity, and it has been proposed that osteogenic biomaterials, which are scaffolds that contain osteocompetent cells, could be used to fill large bone defects. This study investigated the potential of osteogenically-induced human dermal fibroblasts cultured on gelatin microcarriers combined with platelet-rich plasma in a model of a femoral defect in athymic rats. Defects were transplanted with one of the following six combinations: 1 = sodium chloride, 2 = platelet-rich plasma, 3 = microcarriers + platelet-rich plasma, 4 = human dermal fibroblasts on microcarriers + platelet-rich plasma, 5 = human osteoblasts on microcarriers + platelet-rich plasma, and 6 = osteogenically induced human dermal fibroblasts on microcarriers + platelet-rich plasma. The femoral defects were assessed 4 weeks postoperatively with computed tomography (CT), routine histological staining, fluorescence in situ hybridisation, and polyclonal antibodies directed towards osteocalcin and osteonectin. Radiographs of all groups taken 4 weeks postoperatively showed unhealed defects. Femoral defects transplanted with osteogenically-induced human dermal fibroblasts on microcarriers (group 6) contained dense clusters of cells with large quantities of extracellular matrix. These clusters were exclusive to this group and stained strongly for osteocalcin and osteonectin. Fluorescence in situ hybridisation showed viable human cells in femoral defects that had been transplanted with microcarriers seeded with cells, which confirmed the survival of implanted cells. In conclusion, osteogenically-induced human dermal fibroblasts survived in this new niche, and bone-like structures were apparent in the defects.

Sights of touching activates the somatosensory cortex in humans.

We report our observations of cross-modal interactions between sight and touch using functional magnetic resonance imaging (fMRI). Experiments were devised to show that sight and touch are linked in a cross-modal arrangement, and two separate experiments were done in an MRI scanner. In the first, the subject's right hand was stimulated with a brush; in the second, a video sequence was presented to the subject inside the scanner through video goggles in visual three-dimensional stereo, showing one brushstroke every second on a hand in the same manner as the subject had just previously experienced. The result was that both the primary and the secondary somatosensory cortexes were activated in the participants when the hands were touched, and when the subjects saw only a hand being touched in the same manner. The results indicated cross-modal links between sight and touch of the hand in humans.

Cortical activity and hand function restoration in a patient after spinal cord surgery.

BACKGROUND: Following a motorcycle accident, a 9-year-old boy experienced a complete right-sided (dominant) arm and hand paralysis with total sensory loss, Horner syndrome and severe constant pain. This study assessed the long-term outcome of spinal cord surgery undertaken on the patient, focusing on the restored hand function and related cortical activity. The study follows on from previous reports on the same patient. INVESTIGATIONS: Clinical functional and electrophysiological examinations. Functional MRI of cortical activity. DIAGNOSIS: Complete brachial plexus (C5-T1) avulsion from the spinal cord. MANAGEMENT: Spinal cord surgery to restore motor trajectories.

Functional evaluation of regenerated and misrouted low threshold mechanoreceptors and polymodal nociceptors in the skin of rat hindfeet after crush lesions to the sciatic nerve.

Tracer studies on motor axons after nerve crush injuries have indicated that misrouting may occur even when the endoneurium is intact. Misrouting of regenerated polymodal nociceptive C-fibres and low threshold mechanoreceptive axons have been studied functionally in 50 rats three months after unilateral crush lesions to the sciatic nerve. Two weeks before evaluation the tibial fascicle (or the peroneal fascicle) above the lesion was cut and tied off. In this way only functional regeneration of misrouted axons was tested. Misrouted low threshold mechanoreceptive axons and polymodal nociceptor C-fibres were found after regeneration in both glabrous and hairy skin. We conclude that functional misdirection of both myelinated and unmyelinated sensory axons innervating either glabrous or hairy skin can occur after a crush lesion to a peripheral nerve in rats.

Artificial sensibility of the hand based on cortical audiotactile interaction: a study using functional magnetic resonance imaging.

The capacity of the central nervous system for plastic alterations is the base for our ability to adapt to environmental needs. The crossmodal capacity of the brain makes interaction between senses possible, and deprivation of one sense leads to compensatory changes in other senses. We have recently shown how hearing can substitute for sensation in a transplanted insensitive hand by using a sensor glove equipped with small microphones that pick up the sound of friction, which is elicited by active touch. Here we have used functional magnetic resonance imaging (fMRI) in healthy people to illustrate their capacity for cortical audiotactile interaction with activation of the somatosensory cortex induced by auditory stimuli. The phenomenon occurred only in subjects trained to substitute sensibility by hearing, and no audiotactile interaction was found in untrained subjects.