OBJECTIVE To study the compression factor and clinical manifestation of the compression of the palmar cutaneous branch of the median nerve. METHODS Anatomic study was done on both sides of 2 cadavers and 6 cases of hand injury in the debridement, the origin, course, branch of the palmar cutaneous branch of the median nerve were observed. From 1995 to 1998, 12 patients of compression of the palmar cutaneous branch were treated by local blockade injection. Among them, there were 8 males and 4 females, aged from 23 to 65 years and the course of disease ranged 3 to 12 months. RESULTS The palmar cutaneous branch of the median nerve was (1.3 +/- 0.1) mm in diameter, it could be pulled when the wrist dorsi-extension. All cases showed good recovery of hand function and no recurrence after 4 to 12 months follow-up. CONCLUSION The palmar cutaneous branch compression syndrome is closely related to the local anatomy. The diagnosis is definite according to the clinical symptoms and signs, and local blocking is effective on the most patients.
Objective To study the distribution of P2 Y2 receptor in spine cord, dorsal root ganglia and sciatic nerve in rat, and to provide the basis for clarifying the mechanism of the effect of adenosine triphosphate(ATP) on the peripheral nerve regeneration. Methods Six specimens of the spine cord, dorsal root ganglia and sciatic nerve from SD rats were fixed rapidly in 4% paraformaldehyde which included DEPC, imbedded by paraffin and made into ultrathin section. According to the sequence of P2 Y2 receptor’s gene, DNA needle was adopted to detect the distribution of P2 Y2 receptor by hybridization technique in section under the light microscope after theyhad been stained in NBT liquid（50 mg/ml） and BCIP liquid （75 mg/ml）. In thecontrol group, the ultrathin section was only covered with hybridism buffer solution. The result of staining was observed. ResultsHybridization in section showed that P2 Y2 receptor was distributed mainly in the anterior horn cell of spine cordgray matter and Schwann cell of the dorsal root ganglia. No P2 Y2 receptor was observed in the sciatic nerve of both groups. Conclusion P2 Y2 receptor is located mainly in the spine cord and the dorsal root ganglia. Extracellular ATP can affect the cell of spine cord, dorsal root ganglia through P2 Y2 receptor.
OBJECTIVE: To investigate the effect of nerve growth factor(NGF) on the burn wound healing and to study the mechanism of burn wound healing. METHODS: Six domestic pigs weighting around 20 kg were used as experimental animals. Twenty-four burn wound, each 2.5 cm in diameter, were induced on every pigs by scalding. Three different concentrations of NGF, 1 microgram/ml, 2.5 micrograms/ml, 5 micrograms/ml were topically applied after thermal injury, and saline solution used as control group. Biopsy specimens were taken at 3, 5 and 9 days following treatment and immunohistochemistry method was used to detect the epidermal growth factor(EGF), EGF receptor (EGF-R), NGF, NGF receptor (NGF-R), NGF, NGF-R, CD68 and CD3. RESULTS: The expression of EGF, EGF-R, NGF, NGF-R CD68 and CD3 were observed in the experimental group, especially at 5 and 9 days, no expression of those six items in the control group. CONCLUSION: NGF can not only act directly on burn wound, but also modulate other growth factors on the burn wound to accelerate the healing of burn wound.
OBJECTIVE: To investigate the mechanism, diagnosis, and treatment of common fibular nerve compression syndrome secondary to sciatic nerve injury. METHODS: Based on the clinical manifestation and Tinel’s sign at fibular tunnel, 5 cases of common fibular nerve secondary compression following sciatic nerve injury were identified and treated by decompression and release of fibular tunnel. All 5 cases were followed up for 13-37 months, 25 months in average, and were evaluated in dorsal flexion strength of ankle. RESULTS: The dorsal flexion strength of ankle in 4 cases increased from 0-I degrees to III-V degrees, and did not recover in 1 case. CONCLUSION: Fibular tunnel is commonly liable to fibular nerve compression after sciatic nerve injury. Once the diagnosis is established, either immediate decompression and release of the entrapped nerve should be done or simultaneous release of fibular tunnel is recommended when the sciatic nerve is repaired.
ObjectiveTo summarize the applications of Schwann cells (SCs), stem cells, and genetically modified cells (GMCs) in repair of peripheral nerve defects. MethodsThe literature of original experimental study and clinical research related with SCs, stem cells, and GMCs was reviewed and analyzed. ResultsSCs play a key role in repair of peripheral nerve defects; the stem cells can be induced to differentiate into SCs, which can be implanted into nerve conduits to promote the repair of peripheral nerve defect; genetically modified technology can enhance the function of SCs and different stem cells, which has been regarded as a new option for tissue engineered nerve. ConclusionAlthough great progress has been made in tissue engineered nerve recently, mostly limited to the experimental stage. The research of seed cells in application of tissue engineered nerve need be studied deeply.
Objective To construct a bioengineered dermis containing microencapsulated nerve growth factor (NGF) expressing -NIH3T3 cells and to study the effect of the microencapsule on the bioengineered dermis and acute wound healing. Methods A recombinant NGF (PcDNA3.1+/NGF) was constructed and transfected intoNIH-3T3 cells using FuFENETM6 transfection reagent. Positive cell strain was cultured and enclosed in alginate-polylysine-alginate(APA) microcapsules in vitro. Bioengineered dermis was incorporated with NGF-expressing micorencapsules and human fibroblast cells as seed cells using tissue engineering method. The characteristics of the dermis were described by the content of Hydroxyproline(Hyp), HE staining. The content of NGF in the dermis culturing supernatant was measured by ELISA method. These bioengineered dermis were transplanted onto the acute circular full thickness excisional wounds on the dorsum of each swine to observe the rate of reepithelization and wound healing: NGFNIH3T3 microencapsulations(group A), NIH3T3 microencapsulations( group B), empty microencapsulations (group C), NGF incorporated with collagenⅠ( group D) and blank (group E as control group). Results NGF can be tested stably about 124.32 pg/ml in the dermis culturing supernatant after 6 weeks, and the content of Hyp in group A was 69.68±6.20(mg/g wet weight) and increased about 2 times when compared with control groups after 1 week. The tissue engineering skin grafts which can secrete NGF were used to ure the acute wounds and the rate of reepithelization was promoted. The periods of wound healing were 25±2 days in group A, 34±3 days in group B, 34±2 days in group C, 33±2 days in group D and 40±3 days in group E.The period of wound healing was decreased about 10 days at least. Conclusion NGF-expressing NIH3T3 microencapsulates can promote the quality of bioengineered dermis and alsopromote acute wound healing.
Objective To observe in vitro the protective effect of cranial nerve growthine (CNG) on the optic nerve injured by acute ocular hypertension. Methods Thirty white rabbits were divided into five groups,and 6 in each.The acute ocular hypertension(50 mm Hg) models were established by forcing perfusion of normal saline solution into the anterior chamber sustained for 6 h in one eye,and the contral ateral eye of each rabbit was regard as control.Three rabbits in each group were then treated by CNG 0.2 ml intramuscularly every day.The optic nerve and retina was surgically removed at five different time points (lst,3rd,7th,15th and 30th day) after operation.With the HRP orthograde tracing technique and transmitted electron microscope,the effect of CNG on the optic nerve was observed by the changes of axonal transport and ultrastructure of optic nerve. Results Compare with experimental control groups (25.17plusmn;1.03),HRP reactive products of treated groups (39.79plusmn;2.29) markedly increased after seven days (Plt;0.01).The degeneration of axons in treated groups was relatively lighter after fifteen days and some axons recovered after thirty days. Conclusion CNG might improve the axonal transport and the recovery of axons after the optic nerve injured by acute ocular hypertension. (Chin J Ocul Fundus Dis,2000,16:88-90)
Objective To establish an animal model for repairing the sciatic nerve defect with a biodegradable poly D,L-lactic acid/nerve growth factor (PDLLA/NGF) that can control the release conduit in rats and to observe an effect of the conduit on the sciatic nerve regeneration. Methods The PDLLA conduit and the PDLLA/NGF-controlled release conduit (NGF 450 U per conduit) were madewith the solvent-volatilixation method. Forty male SD rats were randomly and equally divided into 4 groups. The middle segments (10 mm) of the sciatic nerves of the rats were excised and were then repaired with the sciatic nerve autograft(Group A), with the PDLLA conduit (Group B), with the PDLLA conduit and an injection of NGF (30 U) into the conduit (Group C), and with the PDLLA/NGF controlled-release conduit (Group D), respectively, with the 10-mm nerve defect left behind. Three months after operation, the morphologic parameters of the nerve regeneration were observed and evaluated under light microscope and electron microscope, and the image analysis was also made. Results Three months after operation, porous adherence between the conduit and the surrounding tissues could be observed. The conduit presented a partial biodegradation but still remainedintact in the outline and the proximal nerve regenerated through the conduit cavity. Based on the histological observation, the quantity, uniformity, and maturity of the nerve fiber regeneration in Groups A and D were better than those in Groups B and C. The image analysis indicated that there were no significant differences in the nerve fiber diameter, axon diameter or myelin thickness between Group A and Group D (P＞0.05). However, all the parameters in Groups A and D were better than those in Groups B and C (P＜0.05). Conclusion The PDLLA/NGF-controlled release conduit can effectively promote the sciatic nerve regeneration of rats. Its morphological index is similar to that of the nerve autograft.
Prevention and treatment of traumatic neuroma by implanting the proximal neural stump into the muscle were studied. Sixteen SD rats were used for the experimental study. The proximal stump of the left sciatic nerve was implanted into the nearby muscle as the experiment side, whereas the proximal stump of the right sciatic nerve was left untreated as the control side. The results were assessed with histological and electrophysiological methods. The experiment demonstrated that neuroma was formed in the control side one month postoperatively, whereas in the experimental side the nerve fibers were dispersed among the muscle fibers and no definite neuroma was formed. Implantation of neural stump into muscle could prevent and treat traumatic neuroma.
ObjectiveThe aim of this study was to evaluate the repair effect of spontaneous reinnervation in rats underwent recurrent laryngeal nerve (RLN) transection. MethodsThirty male Wistar rats (340-360 g) were divided into experiment group (n=15) and blank control group (n=15), and then 15 rats of these 2 groups were divided into 3 time point groups equally:4 weeks group, 8 weeks group, and 12 weeks group. Fifteen rats of experiment group underwent right RLN transection with excision of a 5 mm segment, and other 15 rats of blank control group exposed RLN only, without transection. Grade of vocalization, maximum angle of arytenoid cartilage, axon number of distal part of RLN, and expression of the brain-derived neurotrophic factor (BDNF) in right thyroarytenoid muscle were evaluated at different time points, including 4, 8, and 12 weeks after operation. ResultsGrade of vocalization, maximum angle of arytenoid cartilage, axon numbers of distal part of RLN, and the expression of BDNF in the right thyroarytenoid muscle of experiment group were all lower than those corresponding index of blank control group (P < 0.05), and these indexes of experiment group were restored gradually with time, but failed to reach normal level during the observed time. ConclusionsEven though spontaneous reinnervation is presented after RLN injury, but the effect is unsatisfactory.