Yu-Jun Lin

The value of serial plasma nuclear and mitochondrial DNA levels in patients with acute ischemic stroke

BACKGROUND Elevated circulating cell-free DNA in plasma is reported in several critical diseases. This study hypothesized that since plasma nuclear and mitochondrial DNA substantially increase after acute ischemic stroke and decrease thereafter, their levels can predict treatment outcomes. METHODS Plasma nuclear and mitochondrial DNA levels were serially examined in 50 acute ischemic stroke patients and in 50 at risk control subjects during the study period. RESULTS Levels of plasma nuclear and mitochondrial DNA in patients with acute ischemic stroke were significantly higher than those in the controls (p<0.05). Elevated circulating nuclear DNA in plasma persisted until one month after the acute stroke. Levels of plasma nuclear DNA positively correlated to the clinical severity of stroke as reflected by the National Institutes of Health Stroke Scale. CONCLUSION Levels of plasma nuclear and mitochondrial DNA reflect the severity of cerebral damage after acute cerebral infarction. Assay of plasma DNA levels can be considered a neuro-pathologic marker of patients with acute ischemic stroke.

Comparison of Surface Markers between Human and Rabbit Mesenchymal Stem Cells

This study investigated whether there are marked differences in surface markers between rabbit and human mesenchymal stem cells (MSCs). Murine and rabbit MSCs have been reported to be CD90-negative. Rat MSCs have been reported to be CD71-negative. Our previous study also shows that rabbit MSCs are CD29-negative. However, human MSCs are generally considered to be CD29-, CD71-, and CD90-positive. Therefore, the surface markers of human MSCs might differ from those of other species. Rabbit bone marrow MSCs were obtained that had a multi-differentiation potential. The phenotype of these cells was studied using flow cytometry antibodies for 25 rabbit surface markers, namely, CD13, CD14, CD29, CD31, CD34, CD44, CD45, CD49d, CD49f, CD51, CD54, CD59, CD71, CD73, CD90, CD105, CD106, CD133, CD166, MHC I, MHC II, α-smooth muscle actin (α-SMA), cytokeratin, desmin, and vimentin. The phenotype of commercially available human MSCs was similarly studied using antibodies for human surface markers. CD14, CD31, CD34, CD45, CD49d, CD49f, CD51, CD54, CD71, CD106, CD133, MHC II, and cytokeratin were absent from both rabbit and human MSCs, while CD44, α-SMA, and vimentin were present on both cell lines. CD13, CD29, CD59, CD73, CD90, CD105, CD166, and MHC I were present on human MSCs, but not on rabbit MSCs. However, desmin was present on rabbit MSCs, but not on human MSCs. In total, the surface expression of nine markers differed between human and rabbit MSCs, whereas the surface expression of 16 markers was the same in the two cell lines.

Nocardial brain abscess

Nocardial infections, although rare, are challenging for clinicians to treat. The associated mortality rate remains high; such infections usually occur in immunocompromised patients who have predisposing factors such as malignancy, diabetes mellitus, malnutrition and uremia. However, there have been increasing reports of nocardial infections being observed in immunocompetent patients. Nocardial organisms are mostly isolated from plants and soil, and infection occurs most often as a result of inhalation or direct skin inoculation. Nocardial infections disseminate hematogenously from the primary location to distant end organs, including the brain, kidneys, joints and eyes. Sulfonamides are the drug of choice, based on empirical data. Given the high rate of relapse and the characteristic resistance pattern, treatment should be aggressive and continued for months, with antibiotic treatment being adjusted according to the drug sensitivity test. In our institution, there have been three documented patients with a nocardial brain abscess. All patients were treated with surgical evacuation followed by antibiotics. Here, we report on one patient and review the literature.

Computer-assisted pedicle screw placement for thoracolumbar spine fracture with separate spinal reference clamp placement and registration

BACKGROUND The objective of the study was to improve the accuracy of computer-assisted pedicle screw installation in the spine. This study evaluates the accuracy of computer-assisted pedicle screw placement with separate spinal reference clamp placement and registration on each instrumented vertebra for thoracolumbar spine fractures. METHODS Postoperative radiographs and CT scans assessed the accuracy of pedicle screw placement in 21 adult patients on each instrumented vertebra. Screw placements were graded as good if the screws were placed in the central core of the pedicle and the cancellous portion of the body. Screw placements were graded as fair if the screws were placed slightly eccentrically, causing erosion of the pedicular cortex, and with less than a 2-mm perforation of the pedicular cortex. Screw placements were graded as poor if screws were placed eccentrically with a large portion of the screw extending outside the cortical margin of the pedicle and with more than a 2-mm perforation of the pedicular cortex. RESULTS A total of 140 image-guided pedicle screws were placed in 21 patients: 78 in the thoracic and 62 in the lumbar spine. Of the 140 pedicle screw placements, 96.4% (135/140) were categorized as good; 3.6% (5/140), fair; and 0% were poor. All 5 fair placement screws were placed in the thoracic spine without any mobility. CONCLUSION Separate registration increases accuracy of screw placement in thoracolumbar pedicle instrumentation. Separate spinal reference clamp placement in the instrumented vertebra provides real-time virtual imaging that decreases the possibility of downward displacement during manual installation of the screw.

Rhabdoid papillary meningioma: a clinicopathologic case series study.

World Health Organization (WHO) grade III meningiomas are subclassified on the basis of their architectural pattern into papillary and rhabdoid subtypes. Some meningiomas even combine papillary architecture with rhabdoid cytology. Additionally, they always show malignant histological features, follow an aggressive clinical course and tend to spread through the CSF after frequent local recurrence. We render the first series of rhabdoid papillary meningioma with review of the literature to further elucidate its biological behavior. From six patients (three male, three female), nine specimens of rhabdoid papillary meningioma were obtained between 1994 and 2010. Correlations of histologic parameters, immunohistochemical study, and clinical features were assessed. The mean age of patients was 44.7 years at their first operation. The mean postoperative follow‐up period was 63.2 months. Five patients experienced tumor recurrence, and one of them died from the disease after diffuse leptomeningeal dissemination. The mean time to first recurrence was 28 months. Only one patient was free of tumoral recurrence after an 8‐year follow‐up. Immunohistochemically, all tumors were positive for vimentin and epithelial membrane antigen. MIB‐1 labeling indices were higher following tumor recurrence. The present study expands the clinicopathologic horizon of rhabdoid papillary meningioma and suggests that it will behave aggressively based on its histology and concomitant features of atypia or malignancy or high MIB‐1 labeling indices. Close follow‐up and aggressive treatments of these tumors are warranted.

Statin pre-treatment is associated with lower platelet activity and favorable outcome in patients with acute non-cardio-embolic ischemic stroke

IntroductionStatins reportedly have anti-inflammatory and anti-thrombotic effects aside from cholesterol-lowering. This study aimed to evaluate the effect of pre-existing statin use on platelet activation markers and clinical outcome in acute ischemic stroke patients.MethodsThis prospective study evaluated 172 patients with acute ischemic stroke divided in two groups: patients with pre-existing statin (n = 43) and without pre-existing statin (66 cases with statins initiated post-stroke and 63 without statin treatment). Platelet activation markers (CD62P and CD63) were measured by flow cytometry at different time points after stroke and analyzed with clinical outcome.ResultsThe CD62P and CD63 expressions on platelets were significantly lower in the patients with pre-existing statin use compared to the patients without pre-existing statin use on Day 1 post-stroke (p < 0.05). The CD62P expression was significantly lower in the patients with pre-existing statin use on 90 days after the acute stroke (p < 0.05). Patients with pre-existing statin use had lower incidences of early neurologic deterioration (END) than those without treatment (p < 0.05). Among several baseline clinical variables, admission NIHSS score, history of coronary artery disease, and pre-existing statin use were independent predictions of good clinical outcome at three months.ConclusionsPre-existing statin use is associated with decreased platelet activity as well as improved clinical outcome and reduced END in patients with acute ischemic stroke.

Breast carcinoma metastasis to intracranial meningioma

Meningiomas and breast cancers are common tumors among women in the fifth to seventh decade. However, metastasis from breast cancer to an intracranial meningioma is rare. A 63-year-old woman presented with headache, nausea and vomiting, and progressive right hemiparesis for one month. She had undergone a right modified radical mastectomy in another hospital 10 years prior. At that time, the pathological diagnosis was infiltrating ductal carcinoma. She required adjuvant radiotherapy and chemotherapy for a local recurrence 7 years later. On admission to our hospital, cranial CT scans showed a brightly enhancing, irregularly shaped lesion over the left high parietal lobe with surrounding parenchymal edema. Histopathological examination of the lesion revealed two distinct tumor types, meningioma and metastatic carcinoma of breast tissue origin. Although meningiomas have well-known radiological features, other tumors, including metastases from breast cancers may simulate them. In the clinical setting of previously diagnosed breast cancer, prompt craniotomy for removal of meningioma-like intracranial lesions is recommended to avoid missing the diagnosis of breast cancer metastasis which carries a poorer prognosis than meningioma and requires a different treatment strategy.

The Association Between Symptomatic Delayed Cerebral Infarction and Serum Adhesion Molecules in Aneurysmal Subarachnoid Hemorrhage

BACKGROUND:Serum concentrations of adhesion molecules may be connected to the pathogenesis of delayed cerebral infarction (DCI) after aneurysmal subarachnoid hemorrhage (SAH). OBJECTIVE:To test the hypothesis that levels of adhesion molecules are substantially increased after DCI and decreased thereafter and that these levels can predict treatment outcomes. METHODS:Serial circulating markers of adhesion molecules were examined in 21 consecutive SAH patients and 2 risk control subjects. All underwent cerebral angiography and magnetic resonance imaging to confirm the DCI. The timing of magnetic resonance imaging was fixed in the acute phase and before hospital discharge. RESULTS:Symptomatic DCI developed in 33% of the patients (7 of 21). Statistical analysis of levels of adhesion molecules between patients with and those without DCI revealed that soluble (s) L-selectin, sP-selectin, and sE-selectin concentrations significantly increased after symptomatic DCI (P = .003, .013, and .043, respectively). Only higher sL-selectin level on presentation (cutoff value > 636 ng/mL) was significantly associated with poor outcome after 6 months of follow-up. CONCLUSION:Increased sL-selectin, sP-selectin, and sE-selectin levels imply risks of symptomatic DCI after aneurysmal SAH. The high frequency of symptomatic DCI and higher sL-selectin level on presentation may be associated with worse outcomes.

Predictors and outcome of acute symptomatic cerebral infarctions following aneurysmal subarachnoid hemorrhage

The leading cause of unfavorable outcomes following aneurysmal subarachnoid hemorrhage (SAH) is cerebral infarction. In this 3-year retrospective study, we have retrospectively evaluated 172 hospitalized patients with aneurysmal SAH, and compared those who developed a complicated cerebral infarction with those who did not. In this study, acute symptomatic cerebral infarctions accounted for 22.6% (39/172) of all episodes. Significant statistical analysis between the two patient groups included age at onset, hypertension as the underlying disease, presence of symptomatic vasospasm, mean hospitalization days and Glasgow Outcome Score at the time of discharge. After a minimum 1.5-year follow-up period, the median (interquantile range) Barthel index score was 75 (6–85) for those patients who had cerebral infarctions, and 80 (0–90) for those who had no cerebral infarctions. Multiple logistic regression analysis demonstrated that the presence of symptomatic vasospasm was independently associated with the presence of acute symptomatic cerebral infarctions. The presence of symptomatic vasospasm implies the danger of acute symptomatic cerebral events after aneurysmal SAH. Although our study demonstrates a worse short-term outcome and longer duration of hospitalization in this special group of patients, the functional outcome for patients with cerebral infarction was not inferior to those patients without cerebral infarction after a follow-up of at least 1.5-years.

Clinicopathologic analysis of rhabdoid meningioma

Rhabdoid meningioma is an uncommon variant of meningioma, and was classified separately for the first time in the 2000 World Health Organizations classification of tumors of the nervous system. Because it often shows malignant histological features and follows an aggressive clinical course, it has been classified as a grade III neoplasm. We describe the clinicopathologic features of 13 patients with this rare tumor. From 13 patients (seven male, six female), 19 specimens of rhabdoid meningioma were obtained between 2001 and 2009. The mean age of patients was 50.4years at their first operation. The mean postoperative follow-up period was 35.7months. Five patients experienced tumor recurrence, and two patients died from the disease. The mean time to first recurrence was 36.1months. The recurrence-free survival rates at 1 and 5years were 62% and 23%, respectively. Immunohistochemically, all tumors were positive for vimentin and epithelial membrane antigen. MIB-1 labeling indices were higher following tumor recurrence. Close follow-up and aggressive treatment of these tumors is warranted.