Effects of culture condition and nutrition on the co-production of microbial oil and exopolysaccharide by Sporidiobolus pararoseus JD-2

Microbial oil has been gaining considerable attention from researchers recently as renewable and ecofriendly oil and its potential as feedstock for food industry and biodiesel industry. In this context, we have earlier demonstrated production of microbial oil and exopolysaccharide (EPS) from the yeast Sporidiobolus pararoseus JD-2. In this study, we explored increasing its production by optimizing the culture condition and nutrition. As expected, culture temperature and dissolved oxygen (DO) are the contributing factors for co-producing microbial oil and EPS, in which 28? and lower quantum (i.e., 30 mL/500 mL) show the best conditions in shake-flasks fermentation. By contrast, the initial pH from 4 to 8 has no obvious effect on producing microbial oil and EPS. In addition, the culture nutrition (i.e., carbon/nitrogen source) were also discussed, and indicating that 20 g/L of corn steep liquor and 60 g/L of glucose are beneficial to produce microbial oil and EPS (i.e., 34.1±1.2 g/L and 11.5±0.2 g/L, respectively). Meanwhile, the residue glucose should be maintained at 20 g/L, in which the highest production of microbial oil and EPS was obtained (i.e., 34.6±1.7 g/L and 11.7±0.8 g/L, respectively). The biomass, microbial oil and EPS were further increased during optimizing the DO level, which reached to 67.8±2.1 g/L, 34.7±0.6 g/L and 11.8±0.5 g/L during maintaining DO level at 20-30%, respectively. The results suggest that appropriate culture condition and nutrition considerably improve the fermentation performance of S. pararoseus JD-2 and significantly increase co-production of microbial oil and EPS (by 11.2 and 8.3%, respectively) compared to the un-optimized fermentation.

Clinical evaluation of a bone cement-injectable cannulated pedicle screw augmented with polymethylmethacrylate: 128 osteoporotic patients with 42 months of follow-up

OBJECTIVES: To evaluate the safety and efficacy of a novel bone cement-injectable cannulated pedicle screw augmented with polymethylmethacrylate in osteoporotic spinal surgery. METHODS: This study included 128 patients with osteoporosis (BMD T-score −3.2±1.9; range, −5.4 to -2.5) who underwent spinal decompression and instrumentation with a polymethylmethacrylate-augmented bone cement-injectable cannulated pedicle screw. Postoperative Visual Analogue Scale scores and the Oswestry Disability Index were compared with preoperative values. Postoperative plain radiographs and computed tomography (CT) scans were performed immediately after surgery; at 1, 3, 6, and 12 months; and annually thereafter. RESULTS: The mean follow-up time was 42.4±13.4 months (range, 23 to 71 months). A total of 418 polymethylmethacrylate-augmented bone cement-injectable cannulated pedicle screws were used. Cement extravasations were detected in 27 bone cement-injectable cannulated pedicle screws (6.46%), mainly in cases of vertebral fracture, without any clinical sequela. The postoperative low back and lower limb Visual Analogue Scale scores were significantly reduced compared with the preoperative scores (<0.01), and similar results were noted for the Oswestry Disability Index score (p<0.01). No significant screw migration was noted at the final follow-up relative to immediately after surgery (p<0.01). All cases achieved successful bone fusion, and no case required revision. No infection or blood clots occurred after surgery. CONCLUSIONS: The polymethylmethacrylate-augmented bone cement-injectable cannulated pedicle screw is safe and effective for use in osteoporotic patients who require spinal instrumentation.

Repeated microendoscopic discectomy for recurrent lumbar disk herniation

OBJECTIVES: To explore the microendoscopic discectomy technique and inclusion criteria for the treatment of recurrent lumbar disc herniation and to supply feasible criteria and technical notes to avoid complications and to increase the therapeutic effect. METHODS: A consecutive series of 25 patients who underwent posterior microendoscopic discectomy for recurrent lumbar disc herniation were included. The inclusion criteria were as follows: no severe pain in the lumbar region, no lumbar instability observed by flexion-extension radiography and no intervertebral discitis or endplate damage observed by magnetic resonance imaging. All patients were diagnosed by clinical manifestations and imaging examinations. RESULTS: Follow-up visits were carried out in all cases. Complications, such as nerve injuries, were not observed. The follow-up outcomes were graded using the MacNab criteria. A grade of excellent was given to 12 patients, good to 12 patients and fair to 1 patient. A grade of excellent or good occurred in 96% of cases. One patient relapsed 3 months after surgery and then underwent lumbar interbody fusion and inner fixation. The numerical rating scale of preoperative leg pain was 7.4± 1.5, whereas it decreased to 2.1±0.8 at 7 days after surgery. The preoperative Oswestry disability index of lumbar function was 57.5±10.0, whereas it was 26.0±8.5 at 7 days after surgery. CONCLUSION: In these cases, microendoscopic discectomy was able to achieve satisfactory clinical results. Furthermore, it has advantages over other methods because of its smaller incision, reduced bleeding and more efficient recovery. .

Surgical treatment of the osteoporotic spine with bone cement-injectable cannulated pedicle screw fixation: technical description and preliminary application in 43 patients

OBJECTIVES: To describe a new approach for the application of polymethylmethacrylate augmentation of bone cement-injectable cannulated pedicle screws. METHODS: Between June 2010 and February 2013, 43 patients with degenerative spinal disease and osteoporosis (T-score <-2.5) underwent lumbar fusion using cement-injectable cannulated pedicle screws. Clinical outcomes were evaluated using a Visual Analog Scale and the Oswestry Disability Index. Patients were given radiographic follow-up examinations after 3, 6, and 12 months and once per year thereafter. RESULTS: All patients were followed for a mean of 15.7±5.6 months (range, 6 to 35 months). The Visual Analog Scale and Oswestry Disability Index scores showed a significant reduction in back pain (p = 0.018) and an improvement in lower extremity function (p = 0.025) in patients who underwent lumbar fusion using the novel screw. Intraoperative cement leakage occurred in four patients, but no neurological complications were observed. Radiological observation indicated no loosening or pulling out of the novel screw, and bone fusion was excellent. CONCLUSIONS: The described polymethylmethacrylate augmentation technique using bone cement-injectable cannulated pedicle screws can reduce pain and improve spinal dysfunction in osteoporotic patients undergoing osteoporotic spine surgery. .

Treatment of AO/OTA 31-A3 intertrochanteric femoral fractures with a percutaneous compression plate

OBJECTIVE: AO/OTA 31-A3 intertrochanteric femoral fractures have completely different fracture line directions and biomechanical characteristics compared with other types of intertrochanteric fractures. The choice of the fixation method has been a focus of dispute among orthopedic trauma surgeons. The purpose of this study was to review the outcomes of these fractures treated with a percutaneous compression plate at our institute. METHOD: Seventeen patients with AO/OTA 31-A3 intertrochanteric femoral fractures were treated with a percutaneous compression plate at our institute from January 2010 to December 2011. The clinical data and imaging results were retrospectively analyzed. RESULTS: The medical complication of popliteal vein thrombosis occurred in one patient. Sixteen patients were followed up for 12 to 21 months. Two patients had malunion and mild pain. Fracture collapse occurred in two patients, with one having head penetration. These two patients had moderate pain. There were no occurrences of nonunion or reoperation. The mean Harris hip score obtained during the last follow-up was 84.1 (61-97). Patients with a poor quality of reduction were more likely to have pain results (p = 0.001). A trend existed toward the presence of a poor quality of reduction (p = 0.05) in patients with a collapse of fracture. Patients with poor preoperative mobility were more likely to have a lower Harris hip score (p = 0.000). CONCLUSION: The percutaneous compression plate is an alternative device for the treatment of AO/OTA 31-A3 intertrochanteric femoral fractures. Good fracture reduction and an ideal placement position of the neck screw are important in the success of the device. .

Posterior-only spinal fusion without rib head resection for treating type I neurofibromatosis with intra-canal rib head dislocation

OBJECTIVES: Patients with Type I neurofibromatosis scoliosis with intra-canal rib head protrusion are extremely rare. Current knowledge regarding the diagnosis and treatment for this situation are insufficient. The purpose of this study is to share our experience in the diagnosis and surgical treatments for such unique deformities. METHODS: Six patients with Type I neurofibromatosis scoliosis with rib head dislocation into the spinal canal were diagnosed at our institution. Posterior instrumentation and spinal fusion without intra-canal rib head resection via a posterior-only approach was performed for deformity correction and rib head extraction. The efficacy and outcomes of the surgery were evaluated by measurements before, immediately and 24 months after the surgery using the following parameters: coronal spinal Cobb angle, apex rotation and kyphosis of the spine and the intra-canal rib head position. Post-operative complications, surgery time and blood loss were also evaluated. RESULTS: Patients were followed up for at least 24 months post-operatively. The three dimensional spinal deformity was significantly improved and the intra-canal rib head was significantly extracted from the canal immediately after the surgery. At follow-up 24 months after surgery, solid fusions were achieved along the fusion segments, and the deformity corrections and rib head positions were well maintained. There were no surgery-related complications any time after the surgery. CONCLUSIONS: Systematic examinations are needed to identify patients with Type I neurofibromatosis scoliosis with rib head dislocation into the canal who can be treated by posterior-only spinal fusion without rib head resection. .