Role of the proximal tibiofibular joint on the biomechanics of the knee joint: A three-dimensional finite element analysis.

PURPOSE: The proximal tibiofibular joint (PTFJ) is easily ignored, although many diseases of the knee are caused by PTFJ injuries. Therefore, studying PTFJ biomechanics is very important. The effects of PTFJ injury on ankle function have been reported. However, few studies have assessed the effects of PTFJ injury on the knee joint. This study was performed to describe the biomechanical effects of PTFJ on the knee joint according to a three-dimensional finite element model. METHODS: The knee joint of a healthy volunteer was scanned by CT and MRI. CT and MRI scanning data in DICOM format were imported into Mimics software. Subsequently, 3D models of the normal and PTFJ injured knee, including the bone, cartilage, meniscus and ligament structures were established, and their validity was verified on the basis of available studies in literature. The biomechanical changes in the two knee models under different conditions were compared. RESULTS: The validity of the intact model was verified. No significant difference was observed in tibial mobility in the two models under the conditions of 134 N forward, 10 N·m internal rotation and 10 N·m valgus load. After application of 134 N backward, 10 N·m varus and external rotation load with respect to the tibia, the posterior movement of the tibia and the varus and external rotation angles of the tibia were 3.583±0.892 mm, 4.799±0.092° and 18.963±0.027° in the normal knee model, and 5.127±1.224 mm, 5.277±0.104° and 21.399±0.031° in the PTFJ injury model, respectively, and a significant statistical difference was observed. CONCLUSIONS: PTFJ played an important role in maintaining the posterolateral stability of the knee joint and thus deserves more attention in clinical operations.

Intravitreal Ranibizumab Had Limited Effect on Cystoid Macular Edema Due to Albumin-Bound Paclitaxel: A Case Report and Literature Review.

Angiographically silent cystoid macular edema (CME) is a rare complication from nab-paclitaxel. Here we report a 45-year-old woman with breast cancer who developed CME after several months of treatment with albumin-bound paclitaxel (nab-paclitaxel). Her visual acuity did not improve significantly with the cessation of nab-paclitaxel and intravitreal ranibizumab treatment. Then, brinzolamide eye drops were prescribed. One month later, her vision improved, with the macular edema significantly subsided. Finally, we reviewed other cases of CME induced by nab-paclitaxel that have been reported in the literature and discussed the underlying pathogenesis of nab-paclitaxel-induced CME.

A surgical decompression procedure for effective treatment of calcified lumbar disc herniation.

OBJECTIVE: To present our experience in managing calcified lumbar disc herniation (cLDH) using a surgical decompression procedure. METHODS: Patients who had low back pain radiating to the leg, were preoperatively diagnosed with cLDH by computed tomography and/or magnetic resonance imaging, and were treated with a surgical decompression procedure were studied. Those without cLDH or who were treated with a method other than decompression were excluded. The treatment outcome was analyzed using the visual analog scale (VAS) score, Oswestry Disability Index, and modified Macnab criteria. RESULTS: Thirty-seven patients aged 60.5 ± 9.6 years were evaluated. The VAS scores were significantly decreased 1 day after surgery and remained low at the 3-month and 1-year follow-ups. The Oswestry Disability Index was also significantly lower at the 3-month and 1-year follow-ups. Ninety-four percent of patients rated the results as "excellent" or "good" according to the modified Macnab criteria at the 3-month follow-up. The patients developed few postoperative complications and no recurrence during 1 year of follow-up. CONCLUSION: Our data suggest that the decompression approach is effective for management of cLDH at least in the short term (1 year) with respect to reducing pain and improving patient satisfaction with few complications.

Biomimetic porous silk fibroin/biphasic calcium phosphate scaffold for bone tissue regeneration.

The purpose of our study is to prepare a biomimetic porous silk fibroin (SF)/biphasic calcium phosphate (BCP) scaffold, and evaluate its performance in bone tissue regeneration. The differences in pore size, porosity, mechanical strength and biocompatibility of four different fibroin-containing scaffolds (0, 20, 40, and 60% SF) were studied in vitro. After inoculation with MC3T3-E1 cells, the ectopic bone formation ability of the SF/BCP bionic scaffold was evaluated in a rat model. The SEM and CT demonstrated that compared with pure BCP group (0% SF), the pore size and porosity of SF/BCP scaffolds were proportional to SF content, of which 40% of SF and 60% of SF groups were more suitable for cell growth. The compressive strength of SF/BCP scaffold was greater than that of the pure BCP scaffold, and showed a trend of first increasing and then decreasing with the increase of SF content, among which 40% of SF group had the maximum compressive strength (40.80 + 0.68) MPa. The SF/BCP scaffold had good biocompatibility, under the electron microscope, the cells can be smoothly attached to and propagated on the scaffold. After loading the osteoblasts, it showed excellent osteogenic capacity in the rat model. The SF/BCP scaffold can highly simulate the micro-environment of natural bone formation and can meet the requirements of tissue engineering. The SF/BCP biomimetic porous scaffold has excellent physical properties and biocompatibility. It can highly simulate the natural bone matrix composition and microenvironment, and can promote the adhesion and proliferation of osteoblasts. The SF/BCP scaffold has good ectopic osteogenesis after loading with osteoblasts, which can meet the requirements of scaffold materials in tissue engineering, and has broad application prospects in clinical application.

Mechanisms responsible for the inhibitory effects of epothilone B on scar formation after spinal cord injury.

Scar formation after spinal cord injury is regarded as an obstacle to axonal regeneration and functional recovery. Epothilone B provides moderate microtubule stabilization and is mainly used for anti-tumor therapy. It also reduces scar tissue formation and promotes axonal regeneration after spinal cord injury. The aim of the present study was to investigate the effect and mechanism of the microtubule-stabilizing reagent epothilone B in decreasing fibrotic scarring through its action on pericytes after spinal cord injury. A rat model of spinal cord injury was established via dorsal complete transection at the T10 vertebra. The rats received an intraperitoneal injection of epothilone B (0.75 mg/kg) at 1 and 15 days post-injury in the epothilone B group or normal saline in the vehicle group. Neuron-glial antigen 2, platelet-derived growth factor receptor ß, and fibronectin protein expression were dramatically lower in the epothilone B group than in the vehicle group, but ß-tubulin protein expression was greater. Glial fibrillary acidic protein at the injury site was not affected by epothilone B treatment. The Basso, Beattie, and Bresnahan locomotor scores were significantly higher in the epothilone B group than in the vehicle group. The results of this study demonstrated that epothilone B reduced the number of pericytes, inhibited extracellular matrix formation, and suppressed scar formation after spinal cord injury.

[Epidemiological and etiologic characteristics of ocular fungal infection in Haikou].

OBJECTIVE: To analyze the epidemiological and etiologic characteristics of ocular fungal infection in Haikou. METHODS: The samples of corneal, conjunctivae, anterior chambers, lacrimal sacs were taken from the outpatients and inpatients in the Department of Ophthalmology for fungal culture. The positivity rates of fungal culture were statistically analyzed to describe the seasonal and genus distribution of the fungal infections. RESULTS: A total of 683 patients were involved in this study, and the total positivity rate of fungal culture was 27.96%. The positivity rate was 33.42% in male patients and 21.52% in female patients (P<0.01). The positivity rates were 31.42%, 11.32%, 10.81%, 21.28% and 29.17% in the cornea, conjunctivae, anterior chambers, lacrimal sacs and other locations (P<0.01), and were 34.88%, 22.58%, 11.76%, 4.11%, 21.43% and 13.33% in farmers, workers, teachers, government officers, students and personnel of other occupations (Chi2=39.550, P=0.001), respectively. In terms of age, the rate was 32.30% in 21-40 years group, 31.72% in 41-60 years group, 17.12% in over 60 years group and 26.61% in below 20 years group, showing significant differences (P<0.01). The rates were higher in August, September, October, December, November, all above 30%, but lower in March. Nine genera were identified, including Candida (49.21%), Aspergillus (19.37%), Fusarium (9.42%), mucor (5.76%), Actinomyces (5.24%), Penicillium (3.66%), Saccharomyces (2.62%), non-spore group (1.57%), Alternaria (1.57%), and other genera (1.57%). Among the 94 strains of Candida, 63 (67.02%) belonged to Candida albicans and 14 to Candida tropicalis (14.89%). CONCLUSION: Ocular fungal infection occurs more often in male patients and in the cornea. The common pathogen of ocular fungal infection is Candida, which is different from the etiological characteristics in other areas possibly in association with the tropical climate.