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The employment of laser-Doppler flow (LDF) to allow long-term measurement of blood flow in conscious rats was assessed. Fiber-optic probes were surgically implanted in nine Sprague-Dawley rats. Cortical blood flow (CBF) and medullary blood flow (MBF) were monitored for 11 days using LDF signals. Angiotensin II (ANG II)-induced reactions were also observed. Damage to tissues, changes in urine concentrating capacity and renal activity were very low. This attested to the viability of LDF as CBF and MBF monitor in conscious rats over a prolonged periods.

A Ni-based alloy coating was fabricated on the surface of Q345 low carbon steel by CO2 laser-induction hybrid cladding to improve its surface properties. The physical-mechanical behaviour of the Ni-based alloy coating was investigated in terms of microhardness, nanoindentation, and scratch experiments. The corrosion resistance of the Ni-based alloy coating in acidic solutions was evaluated by electrochemical tests. The results showed that the microstructure of the interface region between the Nibased alloy coating and the Q345 substrate is composed of cellular, columnar, and plane crystals. The main phases of the Ni-based alloy coating included g-Ni, FeNi3, Cr23C6, and B(Fe, Si)3. In the interface region of the coating, the distribution of the microhardness matched the distribution of alloy elements. Nanohardness in the surface and interface regions of the coating were obtained by nanoindentation tests. The elastic-plastic behaviour of the coating was described by a material constitutive equation. No cracks and material loss were observed in the interface region of the Ni-based alloy cladding coating under dynamic load. The good corrosion resistance of the Ni-based alloy coating in acidic environments can be attributed to the presence of a hard phase and ultrafine microstructure. [ABSTRACT FROM AUTHOR]

A novel gold/aniline-pentamer-based electroactive polyamide (Au/EPA) composites that can modify carbon paste electrodes (CPEs) for ascorbic acid (AA) sensing has been studied in detail in this article. Cyclic voltammetry studies indicated improved electrochemical properties of the Au/EPA composites, demonstrating the occurrence of efficient electron/ charge transfer between the Au and the EPA. Experimental tests shows that there is a linear relationship between the concentration of added AA and the response current for the CPE modified with Au/EPA sensor to the concentration of AA in the range of 0.05-0.75 mM (R2 = 0.996, n = 15). The detection limit and the sensitivity of the Au/EPA-CPE AA sensors were 2.75 μM at a signal to noise ratio (S/N) of 3, and 21.7 mA·mM-1, respectively [ABSTRACT FROM AUTHOR]

Objective: Patients with diabetic foot ulcers (DFU) have an increased risk of lower extremity amputation. A retrospective chart review of patients with DFUs attending the Foot Treatment and Assessment chiropodist-led outpatient clinic at an inner-city academic hospital was conducted to determine wound healing outcomes and characteristics contributing to outcomes. Method: We reviewed the complete clinical history of 279 patients with 332 DFUs spanning over a five-year period. Results: The mean age of patients was 61.5±12.5 years and most patients (83.5%) had one DFU. The majority of wounds (82.5%) were in the forefoot. Overall, 267/332 (80.5%) wounds healed. A greater proportion of wounds healed in the forefoot (82.5%) and midfoot (87.1%) than hindfoot (51.9%; p<0.001). Using a logistic regression model, palpable pedal pulse and use of a total contact cast were associated with better wound healing. Conclusion: Our findings are the first to demonstrate the benefits of chiropodists leading an acute care outpatient clinic in the management of DFUs in Canada and delivers wound healing outcomes equivalent to or exceeding those previously published. Declaration of interest: No conflicts of interest to declare. [ABSTRACT FROM AUTHOR]

It is estimated that 2% to 4% of the US population will seek treatment for temporomandibular joint (TMJ) symptoms, typically occurring with anterior disc displacement. The temporomandibular retrodiscal tissue (RDT) has been postulated to restrict pathologic disc displacement. To elucidate RDT function, understanding regional RDT biomechanics and ultrastructure is required. No prior biomechanical analysis has determined regional variations in RDT properties or associated biomechanical outcomes with regional variations in collagen and elastin organization. The purpose of this study was to determine direction- and region-dependent tensile biomechanical characteristics and regional fibrillar arrangement of porcine RDT. Incremental stress relaxation experiments were performed on 20 porcine RDT specimens, with strain increments from 5% to 50%, a ramp-strain rate of 2% per second, and relaxation periods of 2.5 min. Tensile characteristics were determined between temporal and condylar regions and anteroposterior and mediolateral directions. RDT preparations were imaged using second-harmonic generation (SHG) microscopy for both collagen and elastin. Young's modulus showed significant differences by region ( P < 0.001) and strain ( P < 0.001). Young's modulus was <1 MPa from 5% to 20% strain, before increasing from 20% to 50% strain to a maximum of 2.9 MPa. Young's modulus trended higher in the temporal region and mediolateral direction. Instantaneous and relaxed moduli showed no significant difference by region or direction. Collagen arrangement was most organized near the disc boundary, with disorganization increasing posteriorly. Elastin was present at the disc boundary and RDT mid-body. Porcine RDT demonstrated region- and strain-dependent variations in tensile moduli, associated with regional differences in collagen and elastin. The small tensile moduli suggest that the RDT is not resistive to pathologic disc displacement. Further biomechanical analysis of the RDT is required to fully define RDT functional roles. Understanding regional variations in tissue stiffness and ultrastructure for TMJ components is critical to understanding joint function and for the long-term goal of improving TMJ disorder treatment strategies. [ABSTRACT FROM AUTHOR]