Autogenous growth of the hierarchical V-doped NiFe layer double metal hydroxide electrodes for an enhanced overall water splitting.

NiFe layer double metal hydroxide nanosheets (NiFe LDHs) have been extensively investigated as one of the best promising candidates to construct efficient bifunctional catalysts. In this research, element (vanadium) doping into NiFe LDHs grown in nickel foam were synthesized by the one-step method and applied in overall water splitting. The content and structure of the composites were adjusted to regulate the catalyst's electronic structure and reduce the onset potential and achieved unprecedented electrocatalysis for OER and HER. The V-NiFe-LDH/NF showed perfect OER and HER activities with low Tafel slopes of 31.3 and 89.8 mV dec-1, and small overpotentials of 195 and 120 mV at 10 mA cm-2 in 1.0 m KOH solution, respectively. Electrochemical analysis indicated that the efficient catalytic activity of V-NiFe-LDHs/NF mainly benefited from V doping, which optimized the electronic structure and produce defects, thereby resulting in an enhanced conductivity, facile electron transfer, and adequate active sites.

Modified posterior portals for hindfoot arthroscopy.

PURPOSE: The purpose of this study was to determine the course and safe distances achieved with modified coaxial portals for hindfoot arthroscopy and report the clinical results. METHODS: We used 30 embalmed cadaveric ankle specimens and 10 fresh-frozen ankle specimens for anatomic measurements and trial operations. The posteromedial portal via the posterior tibial tendon sheath was first established. The posterolateral portal was subsequently created immediately behind the posterior border of the lateral malleolus and anterior to the peroneal tendons via an inside-out technique. The coaxial portals were finally established with cannulas left in place. In the clinical series, posterior ankle arthroscopy was performed on 18 ankles in 15 patients. All patients were evaluated for any complications with a mean follow-up of 38 months. RESULTS: The posterior tibial nerve, posterior tibial artery, and peroneal artery were located a mean distance of 8.7 mm, 10.1 mm, and 12.9 mm, respectively, from the near edge of the Kirschner wire as a reference to the coaxial portals. The sural nerve and lesser saphenous vein were at greater distances of 27.6 mm and 28.3 mm, respectively. The mean West Point score at the time of the latest follow-up was 91.5 points (range, 76 to 100 points), and there were 9 excellent results, 3 good results, and 1 fair result. No patients showed any complications related to the modified coaxial portals. CONCLUSIONS: The modified coaxial portals seemed to have large distances to the neurovascular structures in our anatomic study. Clinically, this technique was safe, effective, and reproducible. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

A study to identify and characterize the stem/progenitor cell in rabbit meniscus.

The repair of meniscus in the avascular zone remains a great challenge, largely owing to their limited healing capacity. Stem cells based tissue engineering provides a promising treatment option for damaged meniscus because of their multiple differentiation potential. We hypothesized that meniscus-derived stromal cells (MMSCs) may be present in meniscal tissue, and if their pluripotency and character can be established, they may play a role in meniscal healing. To test our hypothesis, we isolated MMSCs, bone marrow-derived stromal cells (BMSCs) and fibrochondrocytes from rabbits. In order to avoid bone marrow mesenchymal stromal cell contamination, the parameniscal tissues and vascular zone of meniscus were removed. The characters of these three types of cells were identified by evaluating morphology, colony formation, proliferation, immunocytochemistry and multi-differentiation. Moreover, a wound in the center of rabbit meniscus was created and used to analyze the effect of BMSCs and MMSCs on wounded meniscus healing. BMSCs & MMSCs expressed the stem cell markers SSEA-4, Nanog, nucleostemin and STRO-1, while fibrochondrocytes expressed none of these markers. Morphologically, MMSCs displayed smaller cell bodies and larger nuclei than ordinary fibrochondrocytes. Moreover, it was certified that MMSCs and BMSCs were all able to differentiate into adipocytes, osteocytes, and chondrocytes in vitro. However, more cartilage formation was found in wounded meniscus filled with MMSCs than that filled with BMSCs. We showed that rabbit menisci harbor the unique cell population MMSCs that has universal stem cell characteristics and posses a tendency to differentiate into chondrocytes. Future research should investigate the mechanobiology of MMSCs and explore the possibility of using MMSCs to more effectively repair or regenerate injured meniscus.

[Sagittal mobility study on the first tarsometatarsal joint in hallux valgus patients and its clinical values].

OBJECTIVE: To study sagittal mobility about the FTJ (first tarsometatarsal joint) and its relationship with the pathophysiology and treatment of hallux valgus patients. METHODS: According to Lee's method, FTJ sagittal mobility of 300 normal feet and 200 hallux valgus was measured, and its correlative factors were statistically analysed. RESULTS: FTJ sagittal mobility of 300 normal feet was 8.4 degrees +/- 2.3 degrees , and that of 200 hallux valgus was 11.7 degrees +/- 3.2 degrees , the difference was significant. The normal range of FTJ sagittal mobility was less than 13 degrees . The sagittal overmotion of FTJ had relation to the anatomical configuration of FTJ (P < 0.05), intercuneiform splitting (P < 0.01), transferred pain under the second metatarsal head (P < 0.01), and FTJ osteoarthritis (P < 0.01) had no relation to HVA (hallux valgus angle), IMA (intermetatarsal angle), second metatarsus medial diaphyseal cortex hypertrophy (P > 0.05). CONCLUSION: Lee's method is convenient and accurate. Both HVA and IMA can not represent the sagittal mobility measurement of FTJ, which should be routinely evaluated, especially for hallux valgus patients with type I FTJ. Lapidus procedure should be considered for patients with larger FTJ in combination with transferred pain under the second metatarsal head, intercuneiform splitting, FTJ osteoarthritis.

[Anatomical study about the posterior coaxial portals via posterior tibial tendon sheath for ankle arthroscopy].

OBJECTIVE: To conduct the anatomical study about the posterior coaxial portals via posterior tibial tendon (PTT) sheath for ankle arthroscopy. METHODS: Coaxial portals were established in 20 ankles by K-wires which were left in place for distance measurement between them and the posterior nerves, tendons and vessels. Ankle arthroscopy was performed in 5 fresh ankles using 2.7 mm 300 arthroscopy with the same portals as mentioned above. The maximum visible scope were recorded and the distance between the arthroscopy and the posterior nerves, tendons and vessels was also measured. RESULTS: The medial portal was located 5 - 12 mm (average, 8 mm) above the tip of medial malleolus, and the lateral portal was located 8 - 24 mm (average, 15 mm) above the tip of lateral malleolus. The coaxial portals, which traversed the PTT sheath and passed posterior to the fibular, not only separated the arthroscopy and instrument from the posterior nerves, tendons and vessels by posterior capsule but also enlarged their distance. The medial and lateral malleolus articular gap, the posterior capsule could be viewed by these portals with as much as 1/2 - 2/3 posterior articular surface of talus. Not only the tibiotalar articular gap but also the dynamic movement between the mortise and the talus were clearly observed. Arthroscopic operation could be performed by instrument through the posterolateral portal. CONCLUSIONS: The posterior coaxial portals via PTT sheath for ankle arthroscopy have such advantages as easy maneuverability, superior safety, clear vision and larger operation field under arthroscopy.

Effects of femoral quality on cementless hip replacement.

OBJECTIVE: To study the clinical influence of fe moral quality on cementless hip replacement and to evaluate cortical index (CI) for femoral quality in order to guide prosthesis choice and rehabilitation. METHODS: Forty-nine cases of cementless hip replacement were followed up for average 3.5 years, 42 of whom had X-ray films on preopera tion or operation day. RESULTS: Harris scores and patients' satisfaction were low bu t pain was significant and prolonged when cortical indices were low. CONCLUSIONS: CI is a reliable semi-quantity parameter for clin ical evaluation of femoral quality. Osteoporosis patients predispose to thigh pa in. Lag for full-weight loading and avoidance for torsion motion can contribute to less pain when CI<=2.2.

[Correlation between expression of aquaporins 1 and chondrocyte apoptosis in articular chondrocyte of osteoarthritis].

OBJECTIVE: The changes of the aquaporins 1 (AQP-1) expression may be related to the chondrocyte apoptosis. To explore the correlation between the expression of AQP-1 and chondrocyte apoptosis by observing the expression of the AQP-1 and the Caspase-3, so as to provide experimental evidence for the further study in the pathogenesis of osteoarthritis (OA). METHODS: Seventy-two 8-week-old clean grade male Sprague Dawley rats, weighing 286-320 g (mean, 300 g), were randomly divided into the operated group (n = 24), the sham-operated group (n = 24), and the control group (n = 24). OA models were made by amputating the anterior cruciate ligament and medial collateral ligament, and partial excision of medial meniscus in operated group; the articular cavity was exposed only in sham-operated group; and no treatment was given in control group. The general condition of the rat was observed after model was established. At 1, 2, 4, and 8 weeks, the specimens of knee joints were harvested to perform the gross and histological observations; the mRNA expressions of AQP-1 and Caspase-3 were determined by real-time fluorescent quantitative PCR; and the activity of the Caspase-3 protease was detected. The correlations between the expression of AQP-1 mRNA and the expressions of Caspase-3 mRNA and protease were analyzed. RESULTS: Totally 6 rats died after operation, and the rats were supplied immediately; the other rats survived to the end of experiment. The appearance and structure of knee articular cartilage were normal in control group and sham-operated group. While in operated group, the cartilage had a rough surface with fissure and vegetation, and fibrosis and irregular cell arrangement were seen on the surface of cartilage. There were significant differences in the Mankin score between the operated group and sham-operated group, control group at 2, 4, and 8 weeks (P < 0.05). There was no significant difference in expressions of the AQP-1 mRNA and Caspase-3 mRNA, and the activity of the Caspase-3 protease among 3 groups at 1 week after operation (P > 0.05); while the expressions of the AQP-1 mRNA, Caspase-3 mRNA, and the activity of the Caspase-3 protease in operated group were significantly higher than those in sham-operated group and control group at 2, 4, and 8 weeks after operation (P < 0.05), and there was an increased trend over time. There was significantly positive correlation (r = 0.817, P = 0.000) between the expressions of AQP-1 mRNA and Caspase-3 mRNA, and the regression equation was y = 0.426 7x(2) + 0.051 5x; meanwhile, there was also significantly positive correlation (r = 0.945, P = 0.000) between the expression of AQP-1 mRNA and the activity of Caspase-3 protease, and the regression equation was y = 15.423 0x + 4.392 8. CONCLUSION: The up-regulation of AQP-1 expression in OA cartilage may be related to the chondrocyte apoptosis, and the changes of AQP-1 expression may involve in the pathogenesis of OA.

[Application of monitoring phosphocreatine kinase continuously and dynamically in early diagnosis of compartment syndrome].

OBJECTIVE: To determine the efficacy of phosphocreatine kinase in the early diagnosis of compartment syndrome. METHODS: Forty patients with compartment syndrome of limbs were reviewed from 2005 to 2008 including 34 males and 6 females with an average age of (37.03 +/- 13.02) years. Monitoring phosphocreatine kinase continuously and dynamically after injured 2, 24 hours, 1, 2, 3 and 4 weeks later. The concentration of CK were measured by using Japanese Olympus automatic biochemistry analysator. The muscle preparations from affected extremity were taken after operation and 1, 2, 3 weeks later for biopsy. RESULTS: Two hours later after injury, the contents of CK increased sharply and the contents of CK were about 20 times more than the nomal. Twenty-four hours later, the contents of CK reached its maximum,the contents of CK were about 42 times more than the nomal. One week later, the contents of CK recovered to normal level. Pathological changes of muscle were irreversible. CONCLUSION: The change of the contents of CK can reflect the progression of disease objectively. If it increased sharply, the chance of compartment syndrome was high. Monitored it dynamicly and continuously can provide assistant for early diagnosis of compartment syndrome and evaluating pathogenetic condition.