Optimization of Recombinant Human Platelet-Derived Growth Factor-BB Encapsulated in Poly (Lactic-co-Glycolic Acid) Microspheres for Applications in Wound Healing

Growth factors play multiple and critical roles in wound repair processes. Platelet-derived growth factor (PDGF) is a potent growth factor that is particularly important in the early inflammatory phase of wound healing. In order to extend the half-life of PDGF, polymeric encapsulation is used. In the current study, Poly (lactic-co-glycolic acid) (PLGA) microspheres containing recombinant human (rh) PDGF-BB were prepared to prolong the effectiveness of this growth factor. PLGA microspheres were optimized using a modified w/o/w-double-emulsion/solvent evaporation method by changing the processing conditions of stirring speed and emulsifier (polyvinyl alcohol) concentration. Microspheres prepared using the optimized method released rhPDGF-BB for up to three weeks. An in vitro migration assay showed a significant decrease in the wound area in cells treated with rhPDGF-BB microspheres compared to control cells. These findings demonstrate the potential of rhPDGF-BB encapsulated in microspheres to enhance wound healing.

Seizure Control in Patients with Extratemporal Lobe Epilepsy

OBJECTIVE: This study was designed to analyze seizure outcome and to investigate the prognostic factors for predicting seizure outcome according to the preoperative evaluations, surgical procedures, topectomy sites and histopathological findings in patients with extratemporal lobe epilepsy (ETLE). METHODS: This study comprised 63 patients with ETLE who underwent surgery. Preoperative evaluations included semiologic analysis, chronic video-EEG monitoring, and neuroimaging studies. Surgical procedures consisted of topectomy in 51 patients, corpus callosotomy in 9, functional hemispherectomy in 2, and vagus nerve stimulation (VNS) in 1. Histopathological findings were reviewed. Postoperative seizure outcomes were assessed by Engel's classification at the average follow up period of 66.8 months. Chi-square test was used for statistics. RESULTS: Total postoperative seizure outcomes were class I in 51 (80%) patients, class II in 6 (10%), class III in 6 (10%). Patients with structural abnormalities on neuroimaging study showed class I in 49 (88%) patients (p0.05). CONCLUSION: A good seizure outcome was obtained in patients with ETLE. The factors for favorable seizure outcome are related to the presence of structural abnormalities on neuroimaging study, and focal and regional ictal EEG onset.

Spinal Intramedullary Lipoma without Dysraphism

Spinal cord lipomas are commonly associated with spinal dysraphism. The lipomas without spinal dysraphism have been reported to be only 1% of all spinal cord lipomas. We report two cases of patients with spinal intramedullary lipomas without dysraphism. One patient was a 57-year-old man who had lower back pain and right-sided sciatica for 20 years. Magnetic resonance imaging (MRI) of the spine demonstrated an intradural mass occupying L1 to L2. The other patient was a 27-year-old woman who had back pain and gait disturbance for 5 months. MRI of the spine showed an elongated intradural mass occupying T7 to T9. Total laminectomy with partial resection of the lesions was performed on both patients. Pathological studies confirmed the diagnosis of spinal cord lipoma. They exhibited no dysraphism. Postoperatively, neurological symptoms improved in both patients.

Management of Unilateral Facet Dislocation of the Cervical Spine

OBJECTIVE: Unilateral facet dislocation of the cervical spine occurs by flexion and rotation injuries and cannot be easily reduced by axial traction. We analyzed 14 consecutive patients with unilateral facet dislocation of the cervical spine to increase knowledge about anatomical reduction of locked facet and factors for successful reduction. METHODS: Fourteen patients (10 men and 4 women) with unilateral facet dislocation of the cervical spine were retrospectively analyzed. Plain X-ray, computerized tomography scan, and magnetic resonance imaging were performed. All patients underwent manual reduction and surgery with anterior interbody fusion and plate fixation. The manual reduction was performed by neck flexion and rotation to the opposite side of dislocation, followed by rotation and flexion of the head toward the side of dislocation and extension with relaxation of traction. Mean follow-up period was 17 months. The level of spine, amount of subluxation, combined facet fracture, and time from injury to initial reduction were analyzed using the data obtained from medical records. RESULTS: Thirteen (93%) patients were reduced successfully. Immediate reduction was achieved in 7 patients but failed in 7 patients. Seven patients underwent delayed closed reduction under general anesthesia, and successful reduction was achieved in 6 patients. Only one patient with bone chips between articular facets failed to achieve anatomical reduction. CONCLUSION: In order to reduce the locked facet more easily and safely, we recommend manipulative traction with anterior interbody fusion and plate fixation under general anesthesia after being aware of spinal cord injury with magnetic resonance imaging.

Congenital Hypoplasia of Internal Carotid Artery Accompanying with Cerebral Aneurys

Hypoplasia of the internal carotid artery is a rare congenital anomaly. Agenesis, aplasia, and hypoplasia of the internal carotid artery (ICA) are frequently associated with cerebral aneurysms in the circle of Willis. Authors report two cases with congenital hypoplasia of the ICA accompanying with the aneurysms. Transfemoral cerebral angiography (TFCA) in one patient identified nonvisualization of the left ICA. Bilateral anterior cerebral artery (ACA) and middle cerebral artery (MCA) were supplied from the right ICA accompanying with two aneurysms at anterior communicating artery (AcoA) and A1 portion of the left ACA. TFCA in another patient demonstrated hypoplastic left ICA and left ACA filled from the right ICA accompanying with AcoA aneurysm. Left MCA was filled from basilar artery via posterior communicating artery (PcoA). Skull base computed tomography (CT) in two patients showed hypoplastic carotid canal. Authors performed direct aneurysmal neck clipping. Follow up CT angiography (CTA) at one year after surgery did not show regrowth or new development of the aneurysm. In patients with hypoplastic ICA, neurosurgeons should be aware of the possibility of development of the aneurysms, presumably because of hemodynamic process. Direct aneurysmal neck clipping is a good treatment modality. After operation, regular CTA, magnetic resonance angiography (MRA) or TFCA is needed to find progressive lesion and to prevent cerebrovascular attack (CVA).

Clinical and Radiologic Assessment for Anterior Cervical Interbody Fusion with Synthetic Cages

OBJECTIVE: This purpose of this study was to determine the clinical efficiency and applicability, and to analyze the radiologic findings of the anterior cervical approach using two synthetic cages for interbody fusion. METHODS: A total of 41 patients with cervical diseases underwent anterior discectomy and interbody fusion with the PEEK Solis(TM) cage in 21 patients and the carbon composite Osta-Pek(TM) cage in 20 patients. Outcome assessment was done using Odom's criteria. Radiological assessment was performed with respect to subsidence, bony fusion and lordosis. The mean follow-up period was 13 months. RESULTS: There were 34 (92.9%) successful cases. The average height of the disc space 12 months after surgery compared to the height before surgery was increased in 28 cases. The height of the disc space 12 months after surgery compared to the height just after surgery was decreased over 3mm in 4 cases, indicating severe subsidence. The use of these synthetic cages have provided the increase in postoperative cervical lordosis. CONCLUSION: There were no significant differences between the Solis(TM) and Osta-Pek(TM) cages on clinical and radiologic outcomes. Both Solis(TM) and Osta-Pek(TM) cages showed low subsidences and complications associated with hardware with good clinical outcomes, high fusion rates, restored disc heights, and restored cervical lordosis.

Study on HBV Gene Replication and Expression of Experimental Hepatitis B Model Using Baculovirus Gene Delivery System

PURPOSE: The lack of reliable in vitro infection systems or convenient animal models has hindered the progress of hepatitis B virus (HBV) research and the development of new treatment options. We established an in vitro model of hepatitis B, using recombinant HBV encoding baculovirus, which provided HBV replication and antigens expression in HepG2 cells. The objectives of this study were to characterize the magnitude of HBV expression and the level of replication obtainable in HepG2 cells, to establish the optimum infection and culture conditions of HBV expression and replication. METHODS: Replication of a competent HBV genome encoding the baculovirus, RC-HBV-Bac, was generated for delivering the HBV genome to HepG2 cells. HBV replication and antigens expression were determined in relation to the infection and culture conditions. RESULTS: In RC-HBV-Bac infected HepG2 cells, HBsAg, HBeAg and HBcAg were expressed in the cytoplasm and nuclei, and secreted into the medium. HBV replication was evidenced by the presence of a replication complex and covalently closed circular (ccc) DNA in the cytoplasmic fraction of infected cells. The level of HBV expression was directly proportional to the multiplication of RC-HBV-Bac infection. Polyethylene glycol was able to enhance the infection efficiency of the baculovirus to HepG2 cells. High levels of HBV replication were achieved under culture conditions supplemented with dimethyl sulfoxide and a low serum concentration. CONCLUSION: This in vitro model of hepatitis B, generated by baculovirus gene delivery, represents a simple and flexible system for the study of HBV replication and drug testing.

Epilepsy Surgery of the Cerebral Paragonimiasis

OBJECTIVE: The authors investigate appropriate evaluation and surgical methods in treatment of the cerebral paragonimiasis accompanying epilepsy. METHODS: Thirteen patients with the cerebral paragonimiasis accompanying epilepsy were included for this study. Preoperative evaluation methods included history taking, skin and serologic tests for Paragonimus westermani, neurologic examinations, computerized tomography, magnetic resonance imaging, amytal test, PET or SPECT, and video-EEG monitoring with depth and subdural grid electrodes. Seizure outcome was evaluated according to Engel's classification. RESULTS: Surgical methods were temporal lobectomy including lesions in six, lesionectomy in five, and temporal lobectomy plus lesionectomy in two. Postoperative neurological complications were not noticed, and seizure outcomes were class I in 12 patients (92%), class II in one (8%). CONCLUSION: In patients with a cerebral paragonimiasis accompanying epilepsy, further evaluation methods must be done to define the epileptogenic zone, and complete resection of the epileptogenic zone with different surgical methods should be performed for seizure control.

Cystic Meningiomas

Cystic Meningiomas are rare tumor. There is a clear prevalance in infants, according for 10~19% of all intracranial meningiomas in this age group, compared with only 2~4% in adults. But, reports of cystic meningioma have been increased in frequency since the introduction of computed tomography(CT) and magnetic resonance image(MRI). Authors report two cases of cystic meningioma in adults. Radiological finding showed extraaxial mass with cystic component. Authors performed total surgical resection of the tumor mass and of the entire cystic component with cystic wall in both patients. Postoperative histopathological diagnosis of the tumor mass was a transitional meningioma in both patients. Both patients showed favorable prognosis and no recurrence findings in follow up MRI.

Surgical Strategies in Patients with the Supplementary Sensorimotor Area Seizure

OBJECTIVE: This study was designed to analyze surgical strategies for patients with intractable supplementary sensorimotor area(SSMA) seizures. METHODS: Seventeen patients who had surgical treatment were reviewed retrospectively. Preoperatively, phase I (non-invasive) and phase II (invasive) evaluation methods for epilepsy surgery were done. Seizure outcome was assessed with Engel's classification. The mean follow-up period was 27.2 months (from 12 months to 54 months). RESULTS: An MRI identified structural abnormality in eight patients and 3D-surface rendering revealed abnormal gyration in three. PET, SPECT, and surface EEG could not delineate the epileptogenic zone. Video-EEG monitoring with a subdural grid or depth electrodes verified the epileptogenic zone in all patients. Surgical procedures consisted of a resection of the SSMA and simultaneous callosotomy in two patients, a resection of the SSMA extending to the adjacent area in seven, a resection of a different area without a SSMA resection in seven, and a callosotomy in one. Seizure outcomes were class I in 11 (65%), class II in five (29%), class III in one (6%). CONCLUSION: In patients with intractable SSMA seizure, surgery was an excellent treatment modality. Precise delineation of the epileptogenic zone based on multimodal diagnostic methods can provide good surgical outcomes without neurological complications.

Retroperitoneal Hematoma Secondary to Terminal Branch of Segmental Artery Injury during Intertransverse Discectomy through Paramedian Muscle Splitting Approach

A 47-year-old man underwent the surgery of intertransverse discectomy through paramedian muscle splitting due to extraforaminal type of far lateral disc herniation at 4th-5th interspace of lumbar vertebrae. The authors encountered the terminal branch of the segmental artery that traversed the extruded disc around the dorsal root ganglion during the sugery. We coagulated the artery by a bipolar coagulator and cut the artery for the discectomy. There was no active bleeding during the surgery. However, the patient suffered from abdominal, right leg and flank pain at the first postoperative day. The follow-up magnetic resonance imaging revealed a retroperitoneal hematoma at the operation site. The patient underwent removal of the retroperitoneal hematoma. We identified the cause of bleeding as the rupture of coagulated terminal branch of the segmental artery around the dorsal root ganglion. The retroperitoneal hematoma was evacuated completely. The ruptured artery was clipped by a small metal clip, and his symptoms subsequently were resolved.