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Microstructural and mechanical characterization of 10 vol% SiC particles (SiCp) reinforced 6061 Al-based composite fabricated by powder thixoforming (PTF) was investigated in comparison with the PTF and permanent mold cast (PMC) 6061 monolithic alloys. The results reveal that the microstructure of the PMC alloy consists of coarse and equiaxed α dendrites and interdendritic net-like eutectic phases. However, the microstructure of the PTF composite, similar to that of the PTF alloy, consists of near-spheroidal primary particles and intergranular secondarily solidified structures except SiCp, which are distributed in the secondarily solidified structures. The eutectics amount in the PTF materials is distinctly lower than that in the PMC alloy, and the microstructures of the former materials are quite compact while that of the latter alloy is porous. Therefore, the PTF alloy shows better tensile properties than the PMC alloy. Owing to the existence of the SiC reinforcing particles, the PTF composite attains an ultimate tensile strength and yield strength of 230 MPa and 128 MPa, representing an enhancement of 27.8% and 29.3% than those (180 MPa and 99 MPa) of the PTF alloy. A modified model based on three strengthening mechanisms was proposed to calculate the yield strength of the PTF composite. The obtained theoretical results were quite consistent with the experimental data. [ABSTRACT FROM AUTHOR]

Objective: To compare the clinical effects of anesthesia and postoperative analgesia for patients with unilateral lower-extremity fracture between multiple injections through catheters beside the lumbar plexus or sciatic nerve and continuous epidural analgesia. Methods: Seventy patients with unilateral lower-extremity fracture scheduled for internal fixation were randomly divided into group N (n = 35) and group E (n = 35). Patients in group N received combined lumbar plexus and sciatic nerve block, then a catheter was inserted into the psoas compartment or beside the sciatic nerve, according to the surgical site, and 25 mL 0.375% ropivacaine was injected into patients in group N through the peripheral nerve catheter 12 hours after operation. Patients in group E received combined spinal and epidural anesthesia, and when the operation was complete kept the epidural catheter and received patient-controlled epidural analgesia with an analgesia pump. Results: The visual analog scores of patients at each time point in the two groups showed no significant difference (P . 0.05). Mean arterial pressure at 30 minutes after anesthesia and 4 hours postoperation in group E decreased significantly and was significantly lower than group N (P , 0.01). Group E had significantly higher rate of urinary retention than group N (P , 0.05), and the time of first food intake of patients in group N was significantly shorter than in group E (P , 0.001). Conclusion: For patients with unilateral lower-extremity fracture receiving internal fixation, multiple injections through catheters beside the lumbar plexus or sciatic nerve can provide adequate postoperative analgesia, with very few adverse effects. [ABSTRACT FROM AUTHOR]

γHerkinorin is an opiate analgesic with limited adverse effects, functioning as a primary selective atypical opioid μ agonist. The present study aimed to identify whether herkinorin has a positive effect on ischemic/reperfusion (I/R) injury. Adult male C57BL/6 mice were randomly divided into five groups: i) Naïve, ii) sham, iii) I/R, iv) I/R with dimethyl sulfoxide (I/R+D) and v) I/R with herkinorin (I/R+H). The I/R injury model was induced by occluding the middle cerebral artery for 1 h followed by 24 h or 7 days of reperfusion. Neurobehavioral scores and sensorimotor functions were examined 24 h and 7 days following reperfusion. In addition, infarct volumes were examined at these time points using a 2,3,5‑triphenyltetrazolium chloride assay. Herkinorin treatment improved neurobehavioral and sensorimotor functional recovery from I/R‑induced brain injury. There was a significant decrease in infarct volume in the I/R+H group at 24 h or 7 days following reperfusion compared with the I/R and I/R+D groups. Western blotting suggested that the decrease in conventional protein kinase C γ (cPKCγ) membrane translocation in the peri‑infarct region may be attenuated by herkinorin pretreatment. These results indicated that herkinorin may be beneficial in I/R‑induced mouse brain injury, and this may be attributed to the membrane translocation of cPKCγ following activation. [ABSTRACT FROM AUTHOR]

Postoperative cognitive dysfunction (POCD), a common clinical in aged patients, is characterized by deficits in cognitive functions in patients following anesthesia and surgery. It has been demonstrated that isoflurane may lead to cognitive impairment in aged rats; however, effective clinical interventions for preventing this disorder are limited. Tumor necrosis factor (TNF)-α has been suggested to be involved in neuroinflammation as well as the development of POCD. Accordingly, the present study aimed to investigate whether TNF-α signaling is involved in the isoflurane-induced cognitive impairment in aged rats, and whether TNF-α receptor antagonist are able to attenuate isoflurane-induced cognitive impairment in aged rats. A population of 20-month-old rats were administered TNF-α receptor antagonist R-7050 or an equal volume of saline by intraperitoneal injection 12 h prior to exposure to isoflurane to model cognitive impairment following anesthesia in old patients. Then the rats were exposed to 1.3% isoflurane for 4 h. In the control group, rats showed impaired cognitive functions evaluated by Morris water maze assay after isoflurane exposure. Furthermore, isoflurane exposure induced marked upregulation of proinflammatory cytokines, including interleukin (IL)-1β, TNF-α, IL-6 and IL-8 in the hippocampus tissue. In the experimental group, intracisternal administration of TNF-α receptor antagonist R-7050 significantly attenuated isoflurane-induced cognitive impairment and upregulation of proinflammatory cytokines. Further investigation revealed that intracisternal administration of TNF-α receptor antagonist R-7050 notably suppressed isoflurane-induced activation of NF-κB and MAPK signaling. Collectively, the present results suggest that TNF-α receptor antagonist may serve as a potential agent for the prevention of anesthesia-induced cognitive decline in aged patients. [ABSTRACT FROM AUTHOR]

A new method, powder thixoforming, has been proposed to fabricate an in situ Al3Tip/2024Al composite. During partial remelting, the microstructural evolution of the bulk alloy prepared by cold pressing of the Ti, Al, 2024Al powder mixture was investigated, and the formation mechanism of the Al3Ti particles produced by the reaction between the Ti powder and the Al alloy melt is also discussed in detail. The results indicate that the microstructural evolution of the 2024 alloy matrix can be divided into three stages: a rapid coarsening of the powder grains; a formation of primary α-Al particles surrounded with a continuous liquid film; and a slight coarsening of the primary α-Al particles. Simultaneously, a reaction layer of Al3Ti can be formed on the Ti powder surface when the bulk is heated for 10 min at 640°C The thickness (X) of the reaction layer increases with the time according to the parabolic law of X= -0.43t2 + 4.21t + 0.17. The stress generated in the reaction layer due to the volume dilatation can be calculated by using the equation ... Comparing the obtained data with the results of the drip experiment, the reaction rate for the Ti powder and Al powder mixture is greater than that for the Ti plate and Al alloy mixture, respectively. [ABSTRACT FROM AUTHOR]

Background: We evaluated the efficacy of a new anesthetic technique termed ultrasound-guided capsule-sheath space block (CSSB) combined with anterior cervical cutaneous nerve block (CCNB) for thyroidectomy. Methods: The study included two parts: Part one was an imaging study to determine technique feasibility. The CSSB was performed on five healthy volunteers by introducing the needle 0.5 cm lateral to the probe under in-plane needle ultrasound guidance. After puncture of the false capsule and its subsequent contraction with the true capsule of thyroid, 10 mL of contrast medium was deposited slowly in the capsule-sheath space. The CCNB was performed bilaterally as follows: Under ultrasound guidance, a subcutaneous injection was made along the sternocleidomastoid using 10 mL of contrast medium which was followed by a girdle-shaped picchu raised from the cricoid cartilage to supraclavicular region. The spreading pattern of contrast medium was imaged using computed tomographic scanning. In part two (a clinical case series) the technique efficacy was evaluated. Seventy-eight patients undergoing thyroidectomy had ultrasound-guided CSSB and CCNB with local anesthetics. The sensory onset of CCNB, intraoperative hemodynamic parameters, and analgesic effect were assessed and complications were noted. Results: The distribution of contrast medium was well defined. In part two the onset time of CCNB was 2.2 ± 0.7 min, and the hemodynamic parameters remained stable intraoperatively. The recall of visual analogue scale scores during surgery was 2 [1-4] for median (range). The patients' and surgeons' satisfaction scores were 2 [1-4] and 1 [1-3] for median (range). No serious complications occurred. Conclusions: Combining ultrasound-guided CSSB and CCNB is a feasible, effective and safe technique for thyroidectomy. [ABSTRACT FROM AUTHOR]

Background: We evaluated the efficacy of a new anesthetic technique termed ultrasound-guided capsule-sheath space block (CSSB) combined with anterior cervical cutaneous nerve block (CCNB) for thyroidectomy. Methods: The study included two parts: Part one was an imaging study to determine technique feasibility. The CSSB was performed on five healthy volunteers by introducing the needle 0.5 cm lateral to the probe under in-plane needle ultrasound guidance. After puncture of the false capsule and its subsequent contraction with the true capsule of thyroid, 10 mL of contrast medium was deposited slowly in the capsule-sheath space. The CCNB was performed bilaterally as follows: Under ultrasound guidance, a subcutaneous injection was made along the sternocleidomastoid using 10 mL of contrast medium which was followed by a girdle-shaped picchu raised from the cricoid cartilage to supraclavicular region. The spreading pattern of contrast medium was imaged using computed tomographic scanning. In part two (a clinical case series) the technique efficacy was evaluated. Seventy-eight patients undergoing thyroidectomy had ultrasound-guided CSSB and CCNB with local anesthetics. The sensory onset of CCNB, intraoperative hemodynamic parameters, and analgesic effect were assessed and complications were noted. Results: The distribution of contrast medium was well defined. In part two the onset time of CCNB was 2.2 ± 0.7 min, and the hemodynamic parameters remained stable intraoperatively. The recall of visual analogue scale scores during surgery was 2 [1-4] for median (range). The patients' and surgeons' satisfaction scores were 2 [1-4] and 1 [1-3] for median (range). No serious complications occurred. Conclusions: Combining ultrasound-guided CSSB and CCNB is a feasible, effective and safe technique for thyroidectomy. Trial registration: Current Controlled Trials ChiCTR-ONC-12002025. Registered 19 March 2012. [ABSTRACT FROM AUTHOR]

Background We evaluated the efficacy of a new anesthetic technique termed ultrasound-guided capsulesheath space block (CSSB) combined with anterior cervical cutaneous nerve block (CCNB) for thyroidectomy. Methods The study included two parts: Part one was an imaging study to determine technique feasibility. The CSSB was performed on five healthy volunteers by introducing the needle 0.5 cm lateral to the probe under in-plane needle ultrasound guidance. After puncture of the false capsule and its subsequent contraction with the true capsule of thyroid, 10 mL of contrast medium was deposited slowly in the capsule-sheath space. The CCNB was performed bilaterally as follows: Under ultrasound guidance, a subcutaneous injection was made along the sternocleidomastoid using 10 mL of contrast medium which was followed by a girdleshaped picchu raised from the cricoid cartilage to supraclavicular region. The spreading pattern of contrast medium was imaged using computed tomographic scanning. In part two (a clinical case series) the technique efficacy was evaluated. Seventy-eight patients undergoing thyroidectomy had ultrasound-guided CSSB and CCNB with local anesthetics. The sensory onset of CCNB, intraoperative hemodynamic parameters, and analgesic effect were assessed and complications were noted. Results The distribution of contrast medium was well defined. In part two the onset time of CCNB was 2.2 ± 0.7 min, and the hemodynamic parameters remained stable intraoperatively. The recall of visual analogue scale scores during surgery was 2 [1-4] for median (range). The patients' and surgeons' satisfaction scores were 2 [1-4] and 1 [1-3] for median (range). No serious complications occurred. Conclusions Combining ultrasound-guided CSSB and CCNB is a feasible, effective and safe technique for thyroidectomy. Trial registration Current Controlled Trials ChiCTR-ONC-12002025. Registered 19 March 2012. [ABSTRACT FROM AUTHOR]