Altered intra- and inter-network brain functional connectivity in upper-limb amputees revealed through independent component analysis.

Although cerebral neuroplasticity following amputation has been observed, little is understood about how network-level functional reorganization occurs in the brain following upper-limb amputation. The objective of this study was to analyze alterations in brain network functional connectivity (FC) in upper-limb amputees (ULAs). This observational study included 40 ULAs and 40 healthy control subjects; all participants underwent resting-state functional magnetic resonance imaging. Changes in intra- and inter-network FC in ULAs were quantified using independent component analysis and brain network FC analysis. We also analyzed the correlation between FC and clinical manifestations, such as pain. We identified 11 independent components using independent component analysis from all subjects. In ULAs, intra-network FC was decreased in the left precuneus (precuneus gyrus) within the dorsal attention network and left precentral (precentral gyrus) within the auditory network; but increased in the left Parietal_Inf (inferior parietal, but supramarginal and angular gyri) within the ventral sensorimotor network, right Cerebelum_Crus2 (crus II of cerebellum) and left Temporal_Mid (middle temporal gyrus) within the ventral attention network, and left Rolandic_Oper (rolandic operculum) within the auditory network. ULAs also showed decreased inter-network FCs between the dorsal sensorimotor network and ventral sensorimotor network, the dorsal sensorimotor network and right frontoparietal network, and the dorsal sensorimotor network and dorsal attention network. Correlation analyses revealed negative correlations between inter-network FC changes and residual limb pain and phantom limb pain scores, but positive correlations between inter-network FC changes and daily activity hours of stump limb. These results show that post-amputation plasticity in ULAs is not restricted to local remapping; rather, it also occurs at a network level across several cortical regions. This observation provides additional insights into the plasticity of brain networks after upper-limb amputation, and could contribute to identification of the mechanisms underlying post-amputation pain.

Hydrogen inhalation promotes recovery of a patient in persistent vegetative state from intracerebral hemorrhage: A case report and literature review.

BACKGROUND: Persistent vegetative state (PVS) is a devastating and long-lasting clinical condition with high morbidity and mortality; currently, there are no available effective interventions. CASE SUMMARY: We report the case of an 11-year-old boy with PVS caused by severe intracerebral bleeding in the left hemisphere following anticoagulation treatment. The patient's PVS severity showed no notable improvement after 2-mo neuroprotective treatment and rehabilitation, including nerve growth factor and baclofen, hyperbaric oxygen, and comprehensive bedside rehabilitation therapies. Daily inhalation treatment (4-6 h) of high-concentration hydrogen (H2) gas (66.6% H2 + 33.3% O2) was provided. Surprisingly, the patient's orientation, consciousness, ability to speak, facial expressions, and locomotor function were significantly restored, along with improvements in essential general health status, after H2 gas inhalation treatment, which was consistent with stabilized neuropathology in the left hemisphere and increased Hounsfield unit values of computed tomography in the right hemisphere. The patient finally recovered to a near normal conscious state with a Coma Recovery Scale-Revised Score of 22 from his previous score of 3. CONCLUSION: Phase 1 clinical trials are needed to explore the safety and efficacy of H2 gas inhalation in patients with PVS.

Factors Related to Instrumentation Failure in Titanium Mesh Reconstruction for Thoracic and Lumbar Tumors: Retrospective Analysis of 178 Patients.

PURPOSE: To investigate risk factors for instrumentation failure (IF) in titanium (Ti) mesh reconstruction for thoracic and lumbar tumors. PATIENTS AND METHODS: The clinical data of patients with thoracic or lumbar tumors who received Ti mesh reconstruction via the posterior approach in our hospital from 2013 to 2018 were analyzed retrospectively. The observation indexes included sex, age, BMI, the vertebra resection mode, the number of resected vertebral segments, application of bone cement, radiotherapy, chemotherapy, revision or primary surgery, and primary tumor metastasis. Correlations between these factors and IF were analyzed by Kaplan-Meier survival and logistics regression analyses. RESULTS: The 178 patients included 108 males and 70 females with a mean age of 48.09±16.21 (6-78) years and a mean follow-up period of 51.18 (24-90) months. The data showed that 17 patients (9.55%) were inflicted with IF, involving the thoracic vertebra in 11 cases, thoracolumbar vertebrae (T12-L1) in 2 cases, and lumbar vertebrae in 4 cases. The mean interval between surgery to IF was 35.18±14.17 (14-59) months. Univariate analysis showed that total vertebral body resection, the number of resected vertebral segments, radiotherapy and multiple tumor resection were potential factors for IF, while multivariate analysis showed that only total vertebral body resection, the number of resected vertebral segments and radiotherapy were independent factors. CONCLUSION: Total vertebra resection, the number of resected vertebral segments (≥2) and radiotherapy before and after operation were significant risk factors related to IF.

Influence of Medial Support Screws on the Maintenance of Fracture Reduction after Locked Plating of Proximal Humerus Fractures.

BACKGROUND: Technical aspects of the correct placement of medial support locking screws in the locking plate for proximal humerus fractures remain incompletely understood. This study was to evaluate the clinical relationship between the number of medial support screws and the maintenance of fracture reduction after locked plating of proximal humerus fractures. METHODS: We retrospectively evaluated 181 patients who had been surgically treated for proximal humeral fractures (PHFs) with a locking plate between September 2007 and June 2013. All cases were then subdivided into one of four groups as follows: 75 patients in the medial cortical support (MCS) group, 26 patients in the medial multiscrew support (MMSS) group, 29 patients in the medial single screw support (MSSS) group, and 51 patients in the no medial support (NMS) group. Clinical and radiographic evaluations included the Constant-Murley score (CM), visual analogue scale (VAS), complications, and revision surgeries. The neck-shaft angle (NSA) was measured in a true anteroposterior radiograph immediately postoperation and at final follow-up. One-way analysis of variance or Kruskal-Wallis test was used for statistical analysis of measurement data, and Chi-square test or Fisher's exact test was used for categorical data. RESULTS: The mean postoperative NSAs were 133.46° ± 6.01°, 132.39° ± 7.77°, 135.17° ± 10.15°, and 132.41° ± 7.16° in the MCS, MMSS, MSSS, and NMS groups, respectively, and no significant differences were found (F = 1.02, P = 0.387). In the final follow-up, the NSAs were 132.79° ± 6.02°, 130.19° ± 9.25°, 131.28° ± 12.85°, and 127.35° ± 8.50° in the MCS, MMSS, MSSS, and NMS groups, respectively (F = 4.40, P = 0.008). There were marked differences in the NSA at the final follow-up between the MCS and NMS groups (P = 0.004). The median (interquartile range [IQR]) NSA losses were 0.0° (0.0-1.0)°, 1.3° (0.0-3.1)°, 1.5° (1.0-5.2)°, and 4.0° (1.2-7.1)° in the MCS, MMSS, MSSS, and NMS groups, respectively (H = 60.66, P < 0.001). There were marked differences in NSA loss between the MCS and the other three groups (MCS vs. MMSS, Z = 3.16, P = 0.002; MCS vs. MSSS, Z = 4.78, P < 0.001; and MCS vs. NMS, Z = 7.34, P < 0.001). There was also significantly less NSA loss observed in the MMSS group compared to the NMS group (Z = -3.16, P = 0.002). However, there were no significant differences between the MMSS and MSSS groups (Z = -1.65, P = 0.225) or the MSSS and NMS groups (Z = -1.21, P = 0.099). The average CM scores were 81.35 ± 9.79, 78.04 ± 8.97, 72.76 ± 10.98, and 67.33 ± 12.31 points in the MCS, MMSS, MSSS, and NMS groups, respectively (F = 18.68, P < 0.001). The rates of excellent and good CM scores were 86.67%, 80.77%, 65.52%, and 43.14% in the MCS, MMSS, MSSS, and NMS groups, respectively (χ2 = 29.25, P < 0.001). The median (IQR) VAS scores were 1 (0-2), 1 (0-2), 2 (1-3), and 3 (1-5) points in the MCS, MMSS, MSSS, and NMS groups, respectively (H = 27.80, P < 0.001). Functional recovery was markedly better and VAS values were lower in the MCS and MMSS groups (for CM scores: MCS vs. MSSS, P < 0.001; MCS vs. NMS, P < 0.001; MMSS vs. MSSS, P = 0.031; and MMSS vs. NMS, P < 0.001 and for VAS values: MCS vs. MSSS, Z = 3.31, P = 0.001; MCS vs. NMS, Z = 4.64, P < 0.001; MMSS vs. MSSS, Z = -2.09, P = 0.037; and MMSS vs. NMS, Z = -3.16, P = 0.003). CONCLUSIONS: Medial support screws might help enhance mechanical stability and maintain fracture reduction when used to treat PHFs with medial metaphyseal comminution or malreduction.

Clinical characteristics and surgical experience of Type III Wagstaffe fractures: Pay attention to concomitant chondral injury of the talus.

BACKGROUND: The purpose of this study was to investigate clinical characteristics and surgical management of Type III Wagstaffe fracture. METHODS: From August 2012 to July 2015, 13 patients with Type III Wagstaffe fractures were surgically treated. During operation, the cartilage of joint surface was explored. Wagstaffe fragment was fixed with cannulated screw or suture, Chaput fragment was fixed with cannulated screw or plate, and Cotton test was performed to evaluate the stability of syndesmosis during the operation. All the patients were followed up for 14.3 months in average. Clinical outcome was assessed with Olerud-Molander score and American Orthopedic Foot and Ankle Society (AOFAS) score. The traumatic arthritis was evaluated with osteoarthritis-score (OA-score). RESULTS: During the operation, chondral injury was found on the lateral top of the talus in 8 cases, as "kissing lesion" of Chaput fragment. The fractures healed uneventfully and all the patients recovered satisfactorily except two had moderate restriction in ankle movement. The average Olerud-Molander score and AOFAS score were 82.3 and 86.1, respectively. CONCLUSION: Type III Wagstaffe is a rare and often missed fracture. 61% are associated with a chondral lesion on the lateral top of the talus. Anatomical reduction and rigid fixation of both fragments are mandatory to obtain ankle stability and good results.

Comprehensive risk assessment and source identification of selected heavy metals (Cu, Cd, Pb, Zn, Hg, As) in tidal saltmarsh sediments of Shuangtai Estuary, China.

Heavy metals do not degrade and can remain in the environment for a long time. In this study, we analyzed the effects of Cu, Cd, Pb, Zn, Hg, and As, on environmental quality, pollutant enrichment, ecological hazard, and source identification of elements in sediments using data collected from samples taken from Shuangtai tidal wetland. The comprehensive pollution indices were used to assess environmental quality; fuzzy similarity analysis and geoaccumulation index were used to analyze pollution accumulation; correlation matrix, principal component analysis, and clustering analysis were used to analyze pollution source; environmental risk index and ecological risk index were used to assess ecological risk. The results showed that the environmental quality was either clean or almost clean. Pollutant enrichment analysis showed that the four sub-regions had similar pollution-causing metals to the background values of the soil element of the Liao River Plain, which were ranked according to their similarity. Source identification showed that all the elements were correlated. Ecological hazard analysis showed that the environmental risk index in the study area was less than zero, posing a low ecological risk. Ecological risk of the six elements was as follows: As > Cd > Hg > Cu > Pb > Zn.

Selective Arterial Embolization for the Treatment of Sacral and Pelvic Giant Cell Tumor: A Systematic Review.

Giant cell tumor of the bone (GCTB) is a locally aggressive tumor with a certain distant metastatic rate. For sacral GCT (SGCT) and pelvic GCT (PGCT), surgery has its limitations, especially for unresectable or recurrent tumors. Selective arterial embolization (SAE) is reported to be an option for treatment in several cases, but there are few systematic reviews on the effects of SAE on SGCT and/or PGCT. Medline and Embase databases were searched for eligible English articles. Inclusion and exclusion criteria were conducted before searching. All the clinical factors were measured by SPSS software, with P-values ≤0.05 considered statistically significant. A total of 9 articles were retrieved, including 44 patients receiving SAE ranging from 1 to 10 times. During the mean follow-up period of 85.8 months, the radiographic response rate was 81.8%, with a local control and overall survival rate of 75% and 81.8%, respectively. No bowel, bladder, or sexual dysfunction was observed. Three patients developed distant metastases and finally died. Patients with primary tumors tended to have better prognosis than those with recurrence (P = 0.039). The favorable outcomes of SAE suggest that it may be an alternative treatment for SGCT and PGCT patients for whom surgery is not appropriate.

HIF1/2α mediates hypoxia-induced LDHA expression in human pancreatic cancer cells.

Glycolysis is a typical conduit for energy metabolism in pancreatic cancer (PC) due to the hypoxic microenviroment. Lactate dehydrogenase A (LDHA) catalyzes the conversion of pyruvate to lactate and is considered to be a key checkpoint of anaerobic glycolysis. The aim of the present study was to explore the mechanism of interactions between hypoxia, HIF-1/2α and LDHA, and the function of LDHA on PC cells by analyzing 244 PC and paratumor specimens. It was found that LDHA was over-expressed and related to tumor stages. The result of in vitro study demonstrated that hypoxia induced LDHA expression. To explore the relationship between HIF and LDHA, chromatin immunoprecipitation assay and luciferase assay were performed. The result showed that HIF-1/2α bound to LDHA at 89bp under the hypoxic condition. Furthermore, knockdown of endogenous HIF-1α and HIF-2α decreased the LDHA expression even in the hypoxic condition, which was accompanied with a significant decrease in lactate production and glucose utilization (p < 0.01). Immunofluorescence in the 244 specimens showed that HIF-1/2α was over-expressed and associated with LDHA over-expression (p < 0.0001). Forced expression of LDHA promoted the growth and migration of PC cells, while knocking down the expression of LDHA inhibited the cell growth and migration markedly. In summary, the present study proved that HIF1/2α could activate LDHA expression in human PC cells, and high expression of LDHA promoted the growth and migration of PC cells.

HIF-1α activates hypoxia-induced BCL-9 expression in human colorectal cancer cells.

B-cell CLL/lymphoma 9 protein (BCL-9), a multi-functional co-factor in Wnt signaling, induced carcinogenesis as well as promoting tumor progression, metastasis and chemo-resistance in colorectal cancer (CRC). However, the mechanisms for increased BCL-9 expression in CRC were not well understood. Here, we report that hypoxia, a hallmark of solid tumors, induced BCL-9 mRNA expression in human CRC cells. Analysis of BCL-9 promoter revealed two functional hypoxia-responsive elements (HRE-B and HRE-C) that can be specifically bound with and be transactivated by hypoxia inducible factors (HIF) -1α but not HIF-2α. Consistently, ectopic expression of HIF-1α but not HIF-2α transcriptionally induced BCL-9 expression levels in cells. Knockdown of endogenous HIF-1α but not HIF-2α by siRNA largely abolished the induction of HIF by hypoxia. Furthermore, there was a strong association of HIF-1α expression with BCL-9 expression in human CRC specimens. In summary, results from this study demonstrated that hypoxia induced BCL-9 expression in human CRC cells mainly through HIF-1α, which could be an important underlying mechanism for increased BCL-9 expression in CRC.

En Bloc Resection of Primary Malignant Bone Tumor in the Cervical Spine Based on 3-Dimensional Printing Technology.

OBJECTIVE: To investigate the feasibility and safety of en bloc resection of cervical primary malignant bone tumors by a combined anterior and posterior approach based on a three-dimensional (3-D) printing model. METHODS: Five patients with primary malignant bone tumors of the cervical spine underwent en bloc resection via a one-stage combined anteroposterior approach in our hospital from March 2013 to June 2014. They comprised three men and two women of mean age 47.2 years (range, 26-67 years). Three of the tumors were chondrosarcomas and two chordomas. Preoperative 3-D printing models were created by 3-D printing technology. Sagittal en bloc resections were planned based on these models and successfully performed. A 360° reconstruction was performed by spinal instrumentation in all cases. Surgical margins, perioperative complications, local control rate and survival rate were assessed. RESULTS: All patients underwent en bloc excision via a combined posterior and anterior approach in one stage. Mean operative time and estimated blood loss were 465 minutes and 1290 mL, respectively. Mean follow-up was 21 months. Wide surgical margins were achieved in two patients and marginal resection in three; these three patients underwent postoperative adjuvant radiation therapy. One vertebral artery was ligated and sacrificed in each of three patients. Nerve root involved by tumor was sacrificed in three patients with preoperative upper extremity weakness. One patient (Case 3) had significant transient radiculopathy with paresis postoperatively. Another (Case 4) with C 4 and C 5 chordoma had respiratory difficulties and pneumonia after surgery postoperatively. He recovered completely after 2 weeks' management with a tracheotomy tube and antibiotics in the intensive care unit. No cerebrovascular complications and wound infection were observed. No local recurrence or instrumentation failure were detected during follow-up. CONCLUSION: Though technically challenging, it is feasible and safe to perform en bloc resection of cervical primary bone tumors. This is the most effective means of managing cervical spine tumors. Preoperative 3-D printing modelling enables better anatomical understanding of the relationship between the tumor and cervical spine and can assist in planning the surgical procedure.

Expression of CDc6 after acute spinal cord injury in adult rats.

The cell division cycle 6 (CDc6) protein has been primarily investigated as a component of the pre-replicative complex for the initiation of DNA replication. Some studies have shown that CDc6 played a critical role in the development of human carcinoma. However, the expression and roles of CDc6 in the central nervous system remain unknown. We have performed an acute spinal cord injury (SCI) model in adult rats and investigated the dynamic changes of CDc6 expression in spinal cord. Western blot have found that CDc6 protein levels first significantly increase, reach a peak at day 3, and then gradually return to normal level at day 14 after SCI. Double immunofluorescence staining showed that CDc6 immunoreactivity was found in neurons, astrocytes, and microglia. Additionally, colocalization of CDc6/active caspase-3 has been detected in neurons and colocalization of CDc6/proliferating cell nuclear antigen has been detected in astrocytes and microglial. In vitro, CDc6 depletion by short interfering RNA inhibits astrocyte proliferation and reduces cyclin A and cyclin D1 protein levels. CDc6 knockdown also decreases neuronal apoptosis. We speculate that CDc6 might play crucial roles in CNS pathophysiology after SCI.

An Up-regulation of IRF-1 After a Spinal Cord Injury: Implications for Neuronal Apoptosis.

IRF-1, a kind of transcription factor, is expressed in many cell types, except in early embryonal cells. IRF-1 has played an essential role in various physiological and pathological processes, including tumor immune surveillance, viral infection, development of immunity system and pro-inflammatory injury. However, the expression and function of IRF-1 in spinal cord injury (SCI) are still unknown. In this study, we have performed an acute SCI model in adult rats and investigated the dynamic changes of IRF-1 expression in the spinal cord. Western blot have shown that IRF-1 protein levels gradually increased, reaching a peak at day 3 and then gradually declined to a normal level at day 14 after SCI. Double immunofluorescence staining showed that IRF-1 immunoreactivity was found in neurons, but not in astrocytes and microglia. Additionally, colocalization of IRF-1/active caspase-3 was detected in neurons. In vitro, IRF-1 depletion, by short interfering RNA, obviously decreases neuronal apoptosis. In conclusion, this is the first description of IRF-1 expression in spinal cord injury. Our results suggested that IRF-1 might play crucial roles in CNS pathophysiology after SCI.

AO X-shaped midfoot locking plate to treat displaced isolated greater tuberosity fractures.

Although various implants exist for 3- and 4-part fractures, few implants are appropriate for isolated greater tuberosity fractures. This retrospective study evaluated the efficacy of AO X-shaped midfoot locking plates for greater tuberosity fractures. Between May 2008 and September 2009, nineteen patients with displaced greater tuberosity fractures were treated with open reduction and internal fixation using AO X-shaped midfoot locking plates. Postoperatively, radiographs, functional results, and complications were evaluated. All patients were followed up for a mean 33.2 months (range, 24-42 months). Mean healing time was 9.4 weeks (range, 8-14 weeks). Mean Constant score was 90.6±4.0 points (range, 77-95 points). Excellent results were obtained in 16 cases, good in 2 cases, moderate in 1 case, and poor in 0 cases. The excellent-good rate was 94.7%. No recurrence of dislocation occurred in the 11 cases with shoulder dislocation. All fractures healed without the complications of wound infection, skin numbness, subacromial impingement syndrome, nonunion, secondary displacement, and implant loosening. The described technique is an effective, simple, and inexpensive method with a short learning curve.

Different functional reorganization of motor cortex after transfer of the contralateral C7 to different recipient nerves in young rats with total brachial plexus root avulsion.

Clinically, contralateral C7 transfer is used for nerve reconstruction in brachial plexus injuries. Postoperatively, synchronous motions at the donor limb are noteworthy. This study studied if different recipient nerves influenced transhemispheric functional reorganization of motor cortex after this procedure. 90 young rats with total root avulsion of the brachial plexus were divided into groups 1-3 of contralateral C7 transfer to anterior division of the upper trunk, to both the musculocutaneous and median nerves, and to the median nerve, respectively. After reinnervation of target muscles, number of sites for forelimb representations in bilateral motor cortices was determined by intracortical microstimulation at 1.5, 3, 6, 9, and 12 months postoperatively. At nine months, transhemispheric reorganization of nerves neurotized by contralateral C7 was fulfilled in four of six rats in group 1, one of six in group 2 and none in group 3, respectively; at 12 months, that was fulfilled in five of six in group 1, four of six in groups 2 and 3, respectively. Logistic regression analysis showed that rate of fulfilled transhemispheric reorganization in group 1 was 12.19 times that in group 3 (95% CI 0.006-0.651, p=0.032). At 12 months, number of sites for hindlimb representations which had encroached upon original forelimb representations on the uninjured side was statistically more in group 3 than in group 2 (t=9.5, p<0.0001). It is concluded that contralateral C7 transfer to upper trunk or to both the musculocutaneous and median nerves induces faster transhemispheric functional reorganization of motor cortex than that to median nerve alone in rats.

The relevance of the anatomical basis of fracture for the subsequent treatment of the anterior humeral circumflex artery and the axillary nerve.

PURPOSE: The purpose of this study was to determine the location of the anterior humeral circumflex artery and axillary nerve based on bony landmarks, and to provide anatomical information that enables a safe approach when treating a proximal humeral fractures. METHODS: Thirty cadavers were included. The distances of both the anterior humeral circumflex artery and the axillary nerve from body landmarks were measured using Vernier calipers. RESULTS: The mean distance between the inferior border of the medial acromion and the superior border of the anterior humeral circumflex artery was 5.1 ± 0.2 cm (range, 4.6-5.5 cm); the mean distance between the prominence of the lesser tuberosity and the superior border of the anterior humeral circumflex artery was 2.5 ± 0.2 cm (range, 2.0-3.0 cm); the mean distance between the anterior-inferior border of the acromion and the superior border of the axillary nerve was 6.3 ± 0.5 cm (range, 5.2-7.0 cm). CONCLUSIONS: The artery is located approximately 5.1 cm below the inferior border of the medial acromion and 2.5 cm below the prominence of the lesser tuberosity, and the nerve was located approximately 6.3 cm below the anterio-inferior border of the acromion and 3.5 cm below the prominence of the greater tuberosity. The reduction manoeuvres should be conducted with extreme care in this region.

Retrospective comparison of titanium elastic nail (TEN) and reconstruction plate repair of displaced midshaft clavicular fractures.

BACKGROUND: Titanium elastic nails (TENs) are commonly used to repair displaced midshaft clavicular fractures. Although several clinical studies have shown that the use of TENs is more effective and less invasive than traditional plate fixation, high rates of complications associated with TENs have been reported. This retrospective study compared the use of TENs with reconstruction plates in the treatment of displaced midshaft clavicular fractures. MATERIALS AND METHODS: From January 2005 to July 2007, 141 patients with displaced midshaft clavicular fractures were treated with TEN or plate fixation. At 6 and 24 months postoperatively, we evaluated the patients' general health, operative complications, and functional recovery. RESULTS: The mean bone union time of TEN patients was 12.4 ± 3.4 weeks, whereas that in the plate group was 14.4 ± 3.7 weeks. The time of union was significantly shorter in the TEN group than that in the plate group. There was no significant difference between these 2 groups' rates of complications such as nonunion or malunion. Shoulder function scores were significantly better in the TEN group than in the plate group at 6 months postoperatively. There was no significant difference at 24 months postoperatively. Patients were more satisfied with the cosmetic appearance and overall outcome after TEN repair than after plate fixation. CONCLUSIONS: TEN fixation of displaced midshaft clavicular fractures allows for a faster functional recovery, higher patient satisfaction, and a more cosmetically satisfactory appearance than plate fixation. The complication rates of both TENs and reconstruction plates were similar.

Identification of CNS neural circuitry involved in the innervation of C7 spinal nerve: a viral transsynaptic tracing study.

OBJECTIVE: Contralateral C7 spinal nerve transfer is a useful operation for the treatment of brachial plexus root avulsion. The recovery of the independent function at the ipsilateral side, however, depends on neural circuitry reorganization in the central nervous system (CNS). This study tried to locate the CNS neuronal elements involved in the innervation of C7 spinal nerve. METHOD: Pseudorabies virus (PRV, TK/gG(-), 2 microlitre), which expressed green fluorescent protein (GFP), was injected into the left C7 spinal nerve in 20 adult Sprague Dawley rats. After rats survived for 6 h, 12 h, 24 h and 36 h, the C1-C7 segments of the spinal cord and brain were processed using a polyclonal immunohistochemical antibody against PRV. RESULTS: PRV-labeled neurons were found mainly in gray matter of the C1-C7 segments of the spinal cord and at the following structures of the brain: lateral vestibular nucleus, lateral paragigantocellular nucleus, A5 cells, red nucleus, primary and secondary motor cortexes, primary and secondary somatosensory cortexes. Although located bilaterally, the PRV-labeled neurons existed predominantly in the ipsilateral side of the spinal cord and the contralateral side of the brain at 6-12 h after injection (p.i.). The number of PRV-labeled neurons in the CNS was increasing with rat's survival time and the distribution of these neurons turned bilateral with no obvious dominance to either side at 24 h and 36 h (p.i.). CONCLUSION: By use of transsynaptic tracing technique with PRV, the anatomically connected set of neurons, which modulates the activity of C7 spinal nerve, is located successfully in the CNS.

BDNF and GAP43 contribute to dynamic transhemispheric functional reorganization in rat brain after contralateral C7 root transfer following brachial plexus avulsion injuries.

It is known that contralateral seventh cervical nerve (C7) root transfer after brachial plexus avulsion injuries (BPAI) causes interhemispheric cortical functional reorganization. However, the potential mechanisms and the role of neurotrophic factors and/or growth-associated protein expression in the process of cerebral reorganization are not well understood. The present study identified the expression of brain-derived neurotrophic factor (BDNF) and growth-associated protein 43 (GAP43) mRNA in primary motor cortex after contralateral C7 root transfer following BPAI. BDNF and GAP43 mRNA levels were significantly increased in brain samples at both 6 and 9 months after contralateral C7 root transfer following BPAI, in comparison with the samples from the rats with BPAI only. These findings indicate that BDNF and GAP43 may play an important role during the dynamic transhemispheric functional reorganization.

Escharectomy and allografting during shock stage reduces insulin resistance induced by major burn.

Hyperglycemia and insulin resistance have long been recognized in severe burn patients. Early excision and grafting reduces cytokines and insulin resistance in burned rats. The authors hypothesized that early wound excision and grafting in patients would also reduce insulin resistance induced by major burn. Thirty-five adult surviving major burn patients (>40%TBSA burn) were recruited. The removal of dead devitalized tissue and allografting in escharectomy group was performed within 72 hours and in control group about 7 days after burn injury. The concentrations of plasma insulin, glucose, and cytokines were measured at 2 and 5 days postburn. Euglycemic-hyperinsulinemic glucose clamps were performed at 5 days after burn. The levels of phosphotyrosine, phosphoserine³¹² of insulin receptor substrate (IRS)-1, and phospho-jun N-terminal kinase (JNK) in muscle were analyzed with immunoprecipitation and Western blotting at 5 days postburn. Escharectomy and allografting during shock stage significantly reduced the levels of interleukin-6 and tumor necrosis factor-α, decreased the levels of phosphoserine³¹² and phospho-JNK, increased the level of phosphotyrosine of IRS-1, and further reduced insulin resistance at 5 days after thermal injury compared with delayed excision group. Escharectomy and allografting during shock stage seemed to have an immunomodulatory effect on the inflammatory mediators and further to reduce insulin resistance induced by major burns in patients by decreasing the phosphorylation of IRS-1 serine³¹² and JNK1/2.