An MRI study of psoas major and abdominal large vessels with respect to the X/DLIF approach.

Extreme/direct lateral interbody fusion (X/DLIF) has been used to treat various lumbar diseases. However, it involves risks to injure the lumbar plexus and abdominal large vessels when it gains access to the lumbar spine via lateral approach that passes through the retroperitoneal fat and psoas major muscle. This study was aimed to determine the distribution of psoas major and abdominal large vessels at lumbar intervertebral spaces in order to select an appropriate X/DLIF approach to avoid nerve and large vessels injury. Magnetic resonance imaging scanning on lumbar intervertebral spaces was performed in 48 patients (24 males, 24 females, 54.2 years on average). According to Moro's method, lumbar intervertebral space was divided into six zones A, I, II, III, IV and P. Thickness of psoas major was measured and distribution of abdominal large vessels was surveyed at each zone. The results show vena cava migrate from the right of zone A to the right of zone I at L1/2-L4/5; abdominal aorta was located mostly to the left of zone A at L1/2-L3/4 and divided into bilateral iliac arteries at L4/5; Psoas major was tenuous and dorsal at L1/2 and L2/3, large and ventral at L3/4 and L4/5. Combined with the distribution of nerve roots reported by Moro, X/DLIF approach is safe via zones II-III at L1/2 and L2/3, and via zone II at L3/4. At L4/5, it is safe via zones I-II in left and via zone II in right side, respectively.

Functional reconstruction of ischemic contracture in the lower limb.

OBJECTIVE: To discuss the method of functional reconstruction of ischemic contracture in the lower limb and propose a classification protocol for ischemic contracture in the lower limb based on its severity and prognosis. METHODS: A total of 42 patients with ischemic contracture in the lower limb were included in this study. According to different types of disturbance and degrees of severity, surgical reconstructions consisting of nerve decompression, tendon lengthening or transfer, intrinsic foot muscle release and sural-tibial nerve anastomosis were performed in every patient. RESULTS: Postoperatively, all patients were able to walk on flat ground. Drop foot was corrected in 10 patients, and 5 patients still felt some difficulty during stair activity. Split Achilles tendon transfer to flexor hallucis longus tendon was performed in 12 patients, and their walking stability was improved. Seven patients accepted ipsilateral sural-tibial nerve anastomosis, and sensitivity recovery reached to S2 in 2 patients and S3 in 5 patients. CONCLUSIONS: Ischemic contracture in the lower limb is a devastating complication after lower limb trauma. The prevention of contracture is much more important than the treatment of an established contracture. Split Achilles tendon transfer to flexor hallucis longus tendon and sural-tibial nerve anastomosis, which was initially implemented by us, could improve the functional recovery of ischemic contracture in lower limbs, and thus provides a new alternative for functional reconstruction of ischemic contracture in the lower limb.

Combined toxicity of outdoor air pollution on kidney function among adult women in Mianyang City, southwest China.

Environmental pollution is a risk factor for kidney dysfunction. However, the combined toxicity of air pollutants on kidney function is scarce. We estimated the relationship between combined toxicity of air pollutants and kidney function among adult women (n = 7071, 18-65 years old) in Mianyang City, Southwest China. We measured serum concentrations of uric acid, urea, creatinine, and cystatin C, and we calculated the individual estimated glomerular filtration rate (eGFR) using a cystatin C-based equation developed specifically for Chinese patients with CKD equation. Air pollution data were collected to calculate the individual average daily dose (ADD) of pollutants based on the air quality complex index (AQCI). Mean AQCI was higher in winter and lower in summer, and followed the monthly and seasonal trends of air pollutants. Concomitantly, individual ADD was also higher in winter and lower in summer, and the seasonal differences were reflected in the levels of kidney biomarkers (including uric acid, urea, creatinine, cystatin C, and eGFR). With an interquartile range (IQR: 1.04-1.50 m3/day/kg) increases of ADD, the serum concentrations of uric acid, urea, creatinine, and cystatin C increase [B (95%CI): 1.774 (0.318, 3.231) umol/L, 0.218 (0.1888, 0.247) mmol/L, 1.501 (1.016, 1.986) umol/L, and 0.006 (0.003, 0.009) mg/L, respectively], whereas eGFR decreases [B (95%CI): -0.776 (-1.106, -0.446) mL/min/1.73 m2]. Totally, the relationship between combined toxicity of air pollutants and kidney function in Chinese adult women suggests that the toxicity of combined air pollutants inversely affects kidney function, which might accelerate the risk of CKD.

Intradural lysis and peripheral nerve implantation for traumatic obsolete incomplete paralysis.

Twenty-eight patients who suffered traumatic obsolete incomplete paralysis were treated with intradural lysis and peripheral nerve implantation by a microsurgery technique. The endorachis was opened and the fibrous bands adhering to the spinal cord from the arachnoid, pia mater spinalis, ligamenta denticulatum, and the initial part of the nerve root were completely relieved. The abnormal spinal cord was then opened by three to six incisions, which were each 0.1 mm to 0.2 mm deep and longer than the abnormal portion. A cyst found in the back or side of the spinal cord was opened and the liquid in it was drained. After that, the denuded spineurium and perineurium of the autogenous sural nerve were grafted, which makes the character and aspect of the nerve like the cauda equine. The nerve was longitudinally implanted into the incised spinal cord, and the cyst was waded with grafted nerve and at least one of them is ectropion sutured with the pia mater with 9-0 scatheless wire as a drain. Finally, the endorachis was covered by sacrospinal muscle flap. These patients were followed for 2 years to 8 years (average 3.5 years), and the sensibility and motion of each increased at least one grade. The strength of the main muscle was increased two grades and reached four grades in 11 patients, and the capability to walk was recovered. Relieving of the adhesion in the endorhachis, carving the cicatricial spinal cord, and implanting the autogenous peripheral nerve yields good results by initial clinical observation for traumatic obsolete and incomplete paralysis.

[Prokaryotic expression, purification and identification of recombinant staphylokinase-HC fusion protein].

AIM: To construct the prokaryotic expression plasmid pEGX-6P-1-SAK-HC, express it in E.coli, and identify its biological activity. METHODS: The fusion gene (SAK-HC) was obtained by overlap-extension PCR and then inserted into prokaryotic soluble pEGX-6P-1 vector with GST tag to construct expression plasmid (pEGX-6P-1-SAK-HC). GST-SAK-HC was expressed by E.coli B834 (DE3) under the induction of IPTG and purified by Glutathion-Sepharose 4B (GST) affinity chromatography and negative-ion exchange column (DEAE) chromatography. PreScission protease was used to remove the GST tag. The purity of the fusion protein was analyzed by SDS-PAGE and the fibrinolytic activity of SAK-HC in vitro was characterized by soluble fibrin plate method. RESULTS: PCR, sequencing and restriction enzyme digestion analysis demonstrated that the recombinant plasmid was constructed successfully. The fusion protein was expressed in E.coli B834 (DE3), M(r); being 36 000 as shown by SDS-PAGE. After purified by GST affinity and DEAE chromatography, SAK-HC fusion protein of high purity was obtained from the cell supernantants. In vitro experiments showed that the fibrinolytic activity of the recombinant SAK-HC was about 9.4×10();4 IU/mg. CONCLUSION: The SAK-HC fusion protein we obtained was successfully expressed in E.coli and exhibited a fibrinolytic activity as high as the urokinase standard, which offers a base for the identification of immunogenicity of the fusion protein.

Functional restoration of the paralyzed diaphragm in high cervical quadriplegia via phrenic nerve neurotization utilizing the functional spinal accessory nerve.

The authors report a case of functional improvement of the paralyzed diaphragm in high cervical quadriplegia via phrenic nerve neurotization using a functional spinal accessory nerve. Complete spinal cord injury at the C-2 level was diagnosed in a 44-year-old man. Left diaphragm activity was decreased, and the right diaphragm was completely paralyzed. When the level of metabolism or activity (for example, fever, sitting, or speech) slightly increased, dyspnea occurred. The patient underwent neurotization of the right phrenic nerve with the trapezius branch of the right spinal accessory nerve at 11 months postinjury. Four weeks after surgery, training of the synchronous activities of the trapezius muscle and inspiration was conducted. Six months after surgery, motion was observed in the previously paralyzed right diaphragm. The lung function evaluation indicated improvements in vital capacity and tidal volume. This patient was able to sit in a wheelchair and conduct outdoor activities without assisted ventilation 12 months after surgery.

Effect of neurotrophin-3 genetically modified olfactory ensheathing cells transplantation on spinal cord injury.

Transplantation of olfactory ensheathing cells (OECs) has emerged as a very promising therapy for spinal cord injury (SCI). Also, local delivery of NT-3 can counteract pathological events and induce a regenerative response after SCI. Supplement of exogenetic NT-3 might be a new approach to SCI repair. In this study, we examined the therapeutic effect of rat NT-3 gene-modified OECs transplantation on SCI. Rat NT-3 gene was transfected into OECs using a retroviral system. The engineered NT-3-OECs were tested for their ability to express and secrete biologically active NT-3 in vitro. Then NT-3-OECs were implanted into contused T9 spinal cord of the adult rats. Their ability of survival and NT-3 production was examined. The effect of axon regeneration was evaluated at the morphological level and promotion of locomotor functional recovery were assessed. The result showed that genetically modified OECs were capable of surviving and producing NT-3 in vivo to significantly improve the recovery after SCI.

[Research progression of tissue transplantation and functional reconstruction of spinal cord].

Functional reconstruction of injured spinal cord depends on its structure restoration,tissue transplantation is the most important strategy in medicine field at present. The tissue applied for transplantation including peripheral nerves, embryonic spinal cord, cellular transplantation and gene organization. However, the results exist dissension. The report overviews the status quo of tissue transplantation, intended to strengthen the recognition of treatment of spinal cord injury.

[Experimental study of peripheral nerve grafts for repairing of chronic spinal cord injury in adult rats].

OBJECTIVE: To explore the pathological mechanism in the repair of chronic spinal cord injury with free grafting of autoperipheral nerve tissues in rats. METHODS: The SD rats were used to establish SCI model with modified Allen method. The rats were divided into two groups at 12 weeks after the injury, each group had 20 rats. In the experimental group, the sural nerves were removed epineurium and transplanted into SCI lesion by using microsurgical technique; and in the control group, the rats were treated without any operation. The survival and differentiation of the grafts, and the ability of repairing host spinal cord were observed under the light microscope at the postoperative 4th and 12th week. Regeneration rates of nerve tracts in spinal cord were evaluated by using HRP tracing technique at the postoperative 4th and 12th week. The morphological changes were observed at section of spinal cord and the motor functions of both hind legs of rats were detected. RESULTS: In the control group, spinal cord exhibited degeneration with cicatrices and cavitates. In the experimental group, peripheral nerve was almost survived, fused with the spinal tissue and axons could regrow into or span the place of injured spinal cord. Higher number of labeled nerve tracts in spinal cord were observed in experimental group, there was significant difference when compared with the control group. Motor function of hind legs of rats recovered significantly in the treatment group. CONCLUSION: Autoperipheral nerve graft tissues transplantation could survive and integrate with the host and have repairing effects on chronic spinal cord injury in rats.