Expression of mRNAs for Neurotrophic Factors in Human Neural Stem Cells Derived from Fetal Telencephalon

OBJECTIVE: Cellular diversity in the mammalian central nervous system is originated from precursor cells present in the neural ectoderm. The multipotent neural stem cells(NSCs) rapidly proliferate to give rise to transiently dividing progenitors that eventually differentiate into several cell types of neural cells. The authors investigate whether NSCs could differentiate neurons and glia and express neurotrophic factor. METHODS: To establish human neural cell lines, we isolated neural stem cells from human fetal telencephalon. Secondly, to investigate the expression of neurotrophic factor, basic fibroblast growth factor(bFGF), brain-derived neurotrophic factor(BDNF) and glial derived neurotrophic factor(GDNF) in rat and human cell, mRNA expressions of bFGF, BDNF and GDNF were detected by the reverse transcripted polymerase chain reaction(RT-PCR) analysis. RESULTS: In the NSCs cultures of embryonic rat striata and human fetal telencephalon, we demonstrated that bFGF induces the proliferation of stem cell, which give rise to spheres of undifferentiated cell that generate neurons and glia. Also, neurotrophic factor transcripts were identified using PCR in rat and human NSCs. CONCLUSION: These results demonstrate that human NSCs derived from human fetal telencephalon could differentiate neurons and glia and express neurotrophic factors. Therefore, NSCs may be an important key for the therapeutic application of neurotrophic factors.

Expression of mRNAs for BDNF and NT-3 in Reactive Astrocytes

OBJECTIVE: Astrocytes secrete various neurotrophic factors which act to support the survival and growth of neurons. Reactive astrocytes express an increased level of neurotrophic factors in response to central nervous system injury. We demonstrate that reactive astrocytes could express neurotrophic factors to promote neuronal rescue and generate functional recovery. METHODS: To investigate the correlation of neurotrophic factor, brain-derived neurotrophic factor(BDNF) and neurotrophin-3(NT-3) to glutamate-induced reactive gliosis, mRNA expression of BDNF and NT-3 were detected by the RT-PCR technique. RESULTS: Exposure of cultured astrocytes to L-glutamate(1, 100, 200 and 500 microM) and scraped astrocytes for 1 day resulted in significant cell damage and we observed mRNA expression of BDNF and NT-3. The maximal expression of BDNF was observed in the control, scraped and L-glutamate treated astrocytes(1 microM). The basal expression of BDNF mRNA in astrocytes treated with L-glutamate(100, 200 and 500 microM) decreased relative to that of control, scraped and L-glutamate treated astrocytes(1 microM). Reactive gliosis, treatment of control astrocytes with glutamate, showed similar pattern for NT-3 mRNA expression. In a word, the basal content of NT-3 mRNA in scrape and L-glutamate(1, 100, 200 and 500 microM) expressed similar to that of control astrocytes. CONCLUSION: This study indicates that the reactive astrocytes also expressed mRNA of BDNF and NT-3 as normal astrocytes.

The Deletion Analysis of Mitochondrial Multicomplexes in Parkinson's Disease

Arkinson's disease(PD) is a neurodegenerative disease involving mainly the loss of dopaminergic neurons in substantia nigra by several factors. The cause of dopaminergic cell death is unknown. Recently, it has been focused on that Parkinson's disease resulting from mitochondrial dysfunction. In the previous studies, it was found that a 5 kilobase(kb) deletion derived from mtDNA dysfunction. And this result leads to a reduction of ATP production, which ultimately causes result in cell death. Blood samples were collected from 6 positive control(PC) and 9 PD patients. Total DNA was extracted twice with phenol followed by chloroform:isoamylalcohol(24: 1). For the analysis of mtDNA, polymerase chain reaction(PCR) and long and accurate polymerase chain reaction(LA PCR) were performed by mitochondrial specific primers. As a result, a deletions of large quantity was detected within several regions of mtDNA in PD patients. The analysis of the partial sequence of the mitochondrial D-loop gene and restriction fragment length polymorphism(RFLP) technique were performed to investigate the point mutation and nucleotide sequence variations between PC and PD patients. Fragment variations between PC and PD were seen in the fragment digested by Hin d III, Eco R V. These variations are attributed to the presence or absence of recognition site by base substitution. Point mutation was observed in the D-loop region. Patients 1 and 2 had one point mutation. Patient 1 had a transition from T to C at 195, and patient 2 had a transversion from A to T. In addition to point mutation, the deletion of mtDNA occurred complexI, III, IV and V subunits in PD patients.

Over-the-top Augmentation with ABC Synthetic Ligament in the Treatment of Acute Rupture of Anterior Cruciate Ligament

PURPOSE: To evaluate the clinical outcome after the over-the-top augmentation with ABC synthetic lig-ament for the treatment of acute rupture of anterior cruciate ligament at least two years follow up. MATERIALS AND METHODS: From January 1992, authors have treated acute rupture of ACL with this method on 91 cases. Among these, 46 cases were available for full data acquisition. At the last follow-up, clinical results were analyzed subjectively and objectively by Lachman, pivot shift test and presence of joint effusion. Functional evaluation was performed by various knee ligament scoring systems and the side-to-side differences were measured with KT-2000 arthrometer. RESULTS: On Lachman test, 82.7% were under grade Iⅈ grade 0 : 17 cases(37%), grade I: 21 cases(45.7%), grade III: 8 cases(17.3%). 89.3% were under grade 0 & Ion pivot shift test. On measure-ment of side-to-side difference, 25 cases(54.3%) were showed difference less than 3 mmand the differences of 16 cases(34.8%) were 3~5 mm. On six cases joint effusions were present. Among these six cases, four cases were accompanied by anterior instability which were brought to second look arthroscopy. Two cases were treated with several times of aspiration and steroid instillation. The one case was failed its continuity which solved with ACL reconstruction with patellar bone-tendon-bone autograft. The other three cases showed only lax ACL which was cared with retightening of ligament at the femoral attach-ment site. At the last follow up, 37 cases(80.4%) were resulted excellent and good on Lysholm score and 41 cases(89.1%) were group A & B on IKDC score. On Tegner scale, 34 cases(73.9%) were above five point. CONCLUSIONS: Authors suggest this over-the-top augmentation of ACL with synthetic polyester ligament would be good treatment option with several advantages; early rehabilitation is possible to get maximal function of knee and no tunnel in the lateral condyle would be good for late ACL reconstruction even though failure of this artificial ligament.

Spinal Meningeal Cysts in Low Back Patients / 대한정형외과학회잡지

The authors reviewed the clinical findings and treatment results of 12 cases of spinal meningeal cysts which were detected in MRI of low back patients. In these lesions, large cysts without CSF communication can compressed the nerve roots within spinal canal and it is difficult to confirm the cause of symptom whether it is originated from cysts or from associated spinal disorders. The terms and classifications of spinal meningeal cysts were very confusing. Among 12 cases, we excised 3 cases of large cysts with gluteal and perianal pains that were caused by compressed sacral nerve roots. All three cases were type 2 cyst (classified by Nabors) and located in sacral canal. In one case associated with isthmic spondylolisthesis, posterolateral fusion and pedicle screw fixations were combined with cyst excision. In other two cases, there were not any spinal pathologic findings that compressed sacral nerve roots except mild degenerative changes and intervertebral disc herniation in lower lumbar and sacral levels All 3 excised cases showed good prognosis in more than one year follow up. The other cases were treated conservatively for the associated spinal disorders.

Treatment of the Unstable Thoracolumbar Spine Fractures Using Posterior Approach / 대한정형외과학회잡지

Continued improvements in treatments of the thoracolumber spine have occured in the last several years. The operative treatment of choice currently is short segment fusion(instrumentation one level above to one level below the injury). The development of pedicle screw systems has brought short segment fusion into clinical reality from the posterior approach. We analysed the clinical results of 20 patients with unstable fracture and fracture-dislocation of thoracolumbar spine who were treated with the posterior transpedicular screw system. The mean fol- low-up was 18 month. Ll was the most common injury level and the bursting fracture was the most common fracure type by Denis classification. The mean preoperative sagital index was 21.5。 and improved 8.1。 postoperatively. The mean preoperative anterior and posterior height of the vertebral height were 56.9% and 88.8% and improved postoperatively 94.7 and 88.8 respectively. The mean preoperative neural canal impingement in neural defici: patient was 47.2% and was improved 30.65% postoperatively. The mean prooperative ASIA motor was 34.1 and improved 41.7 postoperatively. There was no metal failure. These data suggested that the posterior transpedicular screw fixation, transpedicle bone graft, decompression and posterolateral bone graft was able to porvide sufficient stability and to achieve the neurologic improvement.

MRI findings of ruptured intervertebral lumbar discs / 대한정형외과학회잡지

No abstract available.

Clinical Electrophysiological Study on Sick Sinus Syndrome

Nine patients of mean age 47.8 years, with suspected sinus node dysfunction, underwent extensive electrophysiological studies. Sinus bradycardia(6the electrophysiological study, AH and HV intervals were prolonged in 2/9 and 1/9 patients, respectively. Maximal sinus node recovery times were prolonged in 7/9 patients, ranging from 1,330 msec to 12,330msec. Sinoatrial conduction times measured by atrial premature stimulation technique were prolonged in 5/7 patients, ranging from 137msec to 310 msec. And sinoatrial conduction time measured by continuous pacing technique also revealed prolonged value in 4/6 patients ranging from 140 msec to 195 msec. The effective refractory periods, of atrium were prolonged in 6/8 patients (320 msec to 470 msec). The effective and functional refractory periods of AV node were prolonged in 3/8 patients (440 csec to 490 msec) and 4/8 patients (530 msec to 560 msec), respectively. Retrograde VA conduction could be observed in 3/7 patients and ventricular effective refractory periods were normal in 7/7 patients. Atrial flutter was induced in 1/9 patients by electric stimulation during electrophysiological study. Above data suggest that the electrophysiological study is very useful in assessing the sinus node function and other electrophysiological properties in sick sinus syndrome patients and also suggest that the data could be utilized in choosing the proper mode of artificial pacemaker for each patient.