Antimony(III) removal by biogenic manganese oxides formed by Pseudomonas aeruginosa PA-1: kinetics and mechanisms.

In this study, Pseudomonas aeruginosa PA-1, a manganese-oxidizing bacterium screened from the soil at a manganese mining area, was found to be tolerated to Sb(III) stress during the Mn(II) oxidation, and the generated biological manganese oxide (BMO) outperformed the identical type of Abiotic-MnOX in terms of oxidation and adsorption of Sb(III). Adsorption kinetics and isotherm experiments indicated that Sb(III) was primarily adsorbed through chemisorption and multilayer adsorption on BMO; the maximum adsorption capacity of BMO was 143.15 mg·g-1. Removal kinetic studies showed that the Sb(III) removal efficiency by BMO was 72.38-95.71% after 15 min, and it could be up to 96.32-98.31% after 480 min. The removal procedure could be divided into two stages, fast (within 15 min) and slow (15 ~ 480 min), both of which exhibited first-order kinetic behavior. Dynamic fitting in two steps revealed that the removal speed correlated to the level of dissolved Sb(III) with low Sb(III) concentrations, but with the initial concentration being high, the removal speed rate was independent of dissolved Sb(III). During the whole process, the Sb(III) removal speed by BMO was also higher than that by the Abiotic-MnOX. Combining multiple spectroscopic techniques revealed that Sb(V) was generated through the Sb(III) oxidation by BMO and replacing surface metal hydroxyl groups to form the complex internal Mn-O(H)-Sb(V) or generating stable Mn(II)-antimonate precipitates on the surface. In addition, microbial metabolites, including tryptophan and humus, in BMO may be complex with Sb(III) and Sb(V) to achieve the treatment of Sb(III). This research investigates the factors and mechanisms influencing the adsorption and removal of Sb(III) by BMO, which could aid in its future engineering applications for the BMO.

[Lateral closing wedge osteotomy and modified cross pinning with external tension band fixation in the treatment of cubitus varus deformity in childrenLateral closing wedge osteotomy and modified cross pinning with external tension band fixation in the treatment of cubitus varus deformity in children].

OBJECTIVE: To explore the therapeutic effects of distal humeral lateral closing wedge osteotomy followed by modified pinning combined with external tension band fixation in the treatment of cubitus varus deformity in children. METHODS: Total 26 adult patients with cubitus varus deformity were treated by operation from March 2011 to June 2015, 15 patients were boys and the other 11 patients were girls, ranging in age from 4 to 13 years, with an average of 7.8 years. The cubitus varus angel ranged from 11 degrees to 24 degrees, with a mean(17.50±6.73) degrees, 3 patients complicated more than 10 degrees constriction of flexion. Lateral closing wedge osteotomy retaining the medial 3 to 4 mm intact cortex by lateral elbow approach was applied in these 26 patients. The wedge defect were closed and fixed by crossing pinning. The lateral column compression was achieved with external tension band(the crossing pins were bended laterally and the pin ends were hooked mutually). The pre-operative, post-oparetive and contralateral carrying angles were compared and Laupattarakasem criteria was used to evaluate the results at follow-up. RESULTS: All the patients got bony union 2 months after operation and there was no infection or nerve palsy. The average follow-up period was 18.8 months (ranged, 13 to 29 months). The carrying angle was restored to(11.50±3.17) degrees(ranged, 8 to 14 degrees). According to the Laupattarakasem evaluation criteria, 14 patients got an excellent result, 13 good and 1 fair. CONCLUSIONS: Normal carrying angle and elbow flexion could be restored by lateral closing wedge osteotomy, and stable fixation could be achieved with crossing pinning and external tension band, which is available for early mobilization.

[Treatment of refractory lateral epicondylitis with modified Nirschl surgical technique].

OBJECTIVE: To investigate the clinical effects of modified Nirschl surgical techniique in treating refractory lateral epicondylitis. METHODS: From March 2009 to January 2011,21 patients (21 elbows) with refractory lateral epicondylitis were treated in our hospital. There were 8 males and 13 females,ranged in age from 25 to 59 years with an average of (48.3+/-13.4) years and the duration time from 8 to 33 months with an average of (17.1+/-7.7) months;affected position in dominant sides of 16 cases and non-dominant sides of 5 cases. The patients had already received multiple non-operative treatments. Modified Nirschl surgical technique was performed,and operative origination from origin of musculus extensor carpi radialis brevis to discard process with small incision, the process place of extensor digitorum communis would be removed. The incisions were nursed by ice compress for 2 days after operation. Range of motion (ROM) and strengthening exercise of elbow joints started at the 1 week after plaster slab fixation; ROM and strengthening exercise of wrist joints also started at the 2 week after fixation. The pain, power of gripping and patient staisfaction were recorded after operation. Verhaar scaling were used to estimate the recovery. RESULTS: Seventeen patients were followed up from 13 to 22 months with an average of 16.3 months. According to Verhaar standard, 15 cases obtained excellent results and 2 good. No postoperative complication such as instability was found. CONCLUSION: Modified Nirschl surgical technique is an effective method in treating refractory lateral epicondylitis but correct to diagnosis and exclusion the coexisting diseases,accurate removal the process are important guarantee.

[Treatment of anteromedial coronoid facet fractures with open reduction and internal fixation through anteromedial approach].

OBJECTIVE: To investigate the approach of open reduction and internal fixation for the treatment of anteromedial coronoid facet fractures and associated injury. METHODS: From July 2009 to August 2011, 6 coronoid anteromedial facet fractures were treated (4 males and 2 females,the average age was 32.6 years old,ranged from 19 to 49 years old) in our hospital. Three patients had fractures in the left side and 3 in the right(4 dominant sides and 2 non dominant sides). All the patients had close fractures. All the fractures were subtype 2 or subtype 3 of coronoid anteromedial facet fracture according to O'Driscoll classification. The anteromedial incision of elbow and the approach of splitting flexor digitorum superficialis between flexor carpi radialis and palmaris longus were used to apply internal fixation with mini-plate. After fixation of coronoid fracture, widening of radiohumeral joint interspace under varus stress occurred in 3 cases,elbow varus posteromedial rotational instability was showed,and the exploration and repair of radial collateral ligament was not carried out. Plaster was applied for 2 weeks before rehabilitation and the time of plaster application extended to 4 weeks in the patients showed varus posteromedial rotational instability. The motion degree,pain and stability, strength of elbow and hand were recorded,the elbows were evaluated with modified An and Morrey functional rating index. RESULTS: All the patients were followed up,and the average duration was 9.3 months (ranged from 7.5 to 13 months). The strength of elbow and hand were equal to that in the contralateral side. The average flexion was (129.0+/-6.5) degree (ranged from 120 to 135 degree); the average extention was (4.0+/-4.2) degree (ranged from 0 to 10 degree); the average forearm pronation was (84.0+/-6.5) degree (ranged from 75 to 90 degree); average supination was (89.0+/-7.1) degree (ranged from 80 to 100 degree). One patient had ulnar sensory neuropathy after operation and healed in half-year, no postoperative complications as pain and instability accured. All the patients obtained excellent results according to modified An and Morrey functional rating index. CONCLUSION: The approach of splitting flexor digitorum superficialis between flexor carpi radialis and palmaris longus could be used in open reduction and internal fixation of anteromedial coronoid facet farcture, rehabilitation should be postponed in the patient showed elbow varus posteromedial rotational instability.