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ABSTRACT: BackgroundRecent studies showed that the expressions of endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase
(iNOS) after SAH were upregulated and downregulated after subarachnoid haemorrhage (SAH), respectively, implying that NOS
may play a crucial role in SAH-induced vasospasm. Adenosine is a potent vasodilator and an important modulator of cardiac
function. Further studies demonstrated that adenosine A1 receptors decrease the production of NO by arterial endothelial cells. The present study evaluates the effect and possible
mechanism of an adenosine A1 agonist, N6-cyclopentyladenosine (CPA), on SAH-induced vasospasm in a rodent model of SAH.
MethodOne hundred and twelve rats were evenly divided into the following four groups: 1) control (no SAH); 2) SAH only; 3) SAH plus
vehicle; 4) SAH plus CPA (0.003mg/kg). The degree of vasospasm was determined by averaging the cross sectional areas of the
basilar artery 2 days after SAH. Expressions of eNOS and iNOS in basilar artery were also evaluated.
FindingsThere were no significant differences among the control and treated groups in physiological parameters recorded. CPA-treatment
significantly attenuated SAH-induced vasospasm and reversed the down-regulation of eNOS-mRNA and protein after SAH. However,
the post SAH upregulation of iNOS-mRNA and proteins in the basilar artery were not significantly diminished by CPA-treatment.
ConclusionsCPA could partially prevent SAH-induced vasospasm and preserved the downregulation of eNOS expression after SAH. However,
the incomplete anti-spastic effect of CPA may be related to the lack of inhibition of iNOS expression after SAH. Our study
further confirmed the role of iNOS and eNOS in the mediating of vasospasm after SAH.
12/2007: pages 149-153;
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S-L Hwang,
C-L Lin,
K-S Lee,
A-S Lieu,
T-H Kuo,
C-Z Chang,
C-P Yen,
C-K Lin, J-K Loh,
T-Y Huang,
S-L Howng
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ABSTRACT: Seizures and epilepsy in adults are important and increasingly common clinical problems. Despite this, the investigation of seizures in adults with astrocytic tumors remains a grey area. The incidence and influencing factors of preoperative and postoperative seizures were evaluated in 101 patients of 45 years or older with supratentorial astrocytic tumors. Preoperative seizures occurred in 14 (14%) patients. Seizures at presentation were significantly correlated with pathological grades of astrocytic tumors (p = 0.0318). The risk of seizures at presentation was greatest in patients with well-differentiated astrocytomas as compared with anaplastic astrocytomas (Odds ratio = 4.364, p = 0.056) or glioblastomas multiforme (Odds ratio = 5.673, p = 0.007). There was no association of preoperative seizures with age, sex, location or site of the tumors. Postoperative seizures occurred in 18 (18%) patients, including 8 (8/14, 57%) recurrent seizures and 10 (10/87, 12%) late-onset seizures. Postoperative seizures were significantly correlated with the presence of preoperative seizures (p = 0.0003). The presence of preoperative seizures was potentially predictive of postoperative seizures when evaluated by logistic regression model (Odds ratio = 6.650). Thirteen (72%) of 18 patients with postoperative seizures were associated with tumor recurrence in 7 cases, hemorrhage in 3 cases and malignant progression in 3 cases. There was no association of postoperative seizures with age, sex, location or site of the tumors, grades of tumors, type of preoperative seizures, duration of preoperative seizures, serum level of anticonvulsant drug, extent of surgery, postoperative radiation or chemotherapy. The patients with preoperative seizures had a higher risk of postoperative seizures and should be carefully monitored. Imaging examination of brain to exclude the possibilities of tumor recurrence or hemorrhage is warrantable in supratentorial astrocytoma patients with postoperative seizures.
Acta Neurochirurgica 07/2004; 146(6):589-94: discussion 594. · 1.52 Impact Factor
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C L Lin,
A S Lieu,
K S Lee,
Y H C Yang,
T H Kuo,
M H Hung, J K Loh,
C P Yen,
C Z Chang,
S L Howng,
S L Hwang
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ABSTRACT: By the use of conditional probabilities of survival, we studied the yearly survival rates for individual tumor survivors.
Conditional survival rate was estimated in 114 consecutive patients with anaplastic astrocytoma or glioblastoma multiforme. Conditional probabilities of surviving some years given survival to a specific period of time after craniotomy and 95% confidence intervals were calculated in the individual tumor survivors.
The estimated median survival was 30 months for 45 patients with anaplastic astrocytoma and 12 months for 69 patients with glioblastoma multiforme. The conditional probabilities of surviving next one year given survival to 1 year, 2 years, 3 years, 4 years, or 5 years after craniotomy for anaplastic astrocytoma were 86.2%, 75.0%, 85.9%, 77.8%, or 85.7%, respectively; for glioblastoma multiforme 64.8%, 58.7%, 85.7%, 80.0%, or 75.0%, respectively. The conditional probability of surviving to 5 years given survival to 2 years after craniotomy for anaplastic astrocytoma, i.e., surviving an additional 3 years, was 50.1%, which was better than observed 5-year survival rate (28.6%); for glioblastoma multiforme it was 40.2%, which also was better than observed 5-year survival rate (12.4%).
The conditional probability of survival was a good method to clinically predict yearly survival rate for individual tumor survivors. In addition, the method can estimate the probabilities of surviving next some years given survival to a specific period of time after craniotomy. It also showed a more encouraging result than observed survival rate in patients with supratentorial malignant astrocytomas.
Surgical Neurology 12/2003; 60(5):402-6; discussion 406. · 1.67 Impact Factor
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ABSTRACT: The mechanisms by which mexiletine exerts its effects in increasing myocardial circulation, and smooth muscle perfusion and alleviating diabetic neuropathic pain have been widely discussed. The purpose of this study was to examine the protective effect of this compound in ischemia/reperfusion-induced cerebral injury following middle cerebral artery occlusion in Sprague-Dawley rats. Blood flow to the left cerebral hemisphere of the animals was interrupted by occluding the left cerebral artery and both carotid arteries simultaneously for 3 hrs. These animals were assigned to one of ten groups and divided into treatment group and pretreatment group; 1) control treatment group (n=8); 2) vehicle treatment group (n=8); 3) lower dose mexiletine (400 microg/kg) treatment group (n=8); 4) medium dose mexiletine (800 microg/kg) treatment group (n=8); 5) high dose mexiletine (2 mg/kg) treatment group (n=8); 6) control pretreatment group (n=8); 7) vehicle pretreatment group (n=8); 8) lower dose mexiletine (400 microg/kg) pretreatment group (n=8); 9) medium dose mexiletine (800 microg/kg) pretreatment group (n=8); and 10) high dose mexiletine (2 mg/kg) pretreatment group (n=8). The volume of cerebral infarction was measured in serial brain sections stained with triphenyltetrazolium chloride (TTC). Tissue infarction volume and tissue edema were estimated for each animal. The volume of cerebral infarction was significantly decreased in rats pretreated with mexiletine, and the ratio of tissue edema was also decreased as the dose of mexiletine increased. These results demonstrate that mexiletine, an anti-arrhythmic and use-dependent Na+ channel blocker, has protective effects in stroke at concentrations sufficient to confer significant protection, as measured by the volume of infarction and brain edema index in a model of focal, neocortical ischemia in Sprague-Dawley rats.
Acta Neurochirurgica 03/2002; 144(2):189-93; discussion 193. · 1.52 Impact Factor
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ABSTRACT: Long-term extracranial shunting for hydrocephalus has numerous drawbacks related to shunt malfunction and infection. The outcomes have been very disappointing in some cases. We have treated twenty one patients with obstructive hydrocephalus, without mortality or morbidity, using a flexible endocope to perform third ventriculostomy. Favorable outcomes were achieved in 95.2% of the cases. Our results are superior to those previously reported. Most of the patients remained shunt independent after treatment and had obtained long-term stabilization. Flexible endoneurosurgical management is simple and safe, and it allows in situ observation and performance of biopsies. Therefore, in patients with obstructive hydrocephalus due to aqueductal stenosis, endoscopic third ventriculostomy should be seriously considered as the primary surgical management.
The Kaohsiung journal of medical sciences 11/2000; 16(10):510-6. · 0.61 Impact Factor
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ABSTRACT: The improved diagnostic capacity of computed tomography (CT) may have resulted in improved detection of intracranial tumors. We were interested to know whether the frequency of intracranial tumors has changed after the introduction of CT in Taiwan. The relative incidences of intracranial tumors in Taiwan were analyzed from the hospital based data. Our data showed that meningiomas were the most encountered intracranial tumors. Neuroepithelial tumors in our series (in the post-CT era) (23.9%) were apparently lower than those found in the pre-CT era (36.0%). However, the relative incidences of meningiomas and pituitary adenomas after the use of CT (24.2%, 21.1%, respectively) were much higher than those found before the use of CT (14.5%, 7.7%, respectively). Our data suggest that the increased incidence for benign tumors and the decreased incidence for malignant tumors may have resulted from the improved diagnostic capacity of CT, which reduces the number of undetected tumor cases.
The Kaohsiung journal of medical sciences 08/2000; 16(7):345-50. · 0.61 Impact Factor
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ABSTRACT: We reviewed our experience in 42 children younger than 16 years with spontaneous intracerebral hemorrhage (ICH) treated between January 1989 and December 1997. Glasgow coma scale (GCS) on admission was 15 in 21 (50%) patients. The most frequent presenting symptoms were headache in 28 (67%) patients, followed by loss of consciousness in 22 (52%) patients and vomiting in 21 (50%) patients. Three cases were diagnosed initially as meningitis and two cases as common cold. The locations of ICH were lobar (26 patients) and cerebellar (7). Cerebral angiographies were performed on 28 patients, and were diagnostic in 19 (68%). Magnetic resonance imaging (MRI) scans revealed two cases of cavernous angiomas, which were confirmed by the pathologic studies of surgical specimens. Laboratory examinations detected two cases of acute leukemia. Four categories of the causes of ICH were determined in 23 (55%) patients. The leading cause of bleeding was arteriovenous malformations (AVMs). The in-hospital survival rate of all patients in this study was 79%. Patients with GCS 3-5 on admission and ICH located at brain stem, cerebellum, and multiple subcortical areas had higher mortality rates. On the follow-up (mean 42 months), seventy percent of our cases had made a good recovery, 21% a fair recovery, 3% a poor recovery, and 6% had died. Children with ICH recover motor function more rapidly than adults. However, visual deficits always persist at our long-term follow-up examinations. A physician should keep in mind the diagnosis of ICH in children, even though the presenting symptoms may be non-specific and the incidence of ICH is very low in children.
The Kaohsiung journal of medical sciences 04/1999; 15(3):146-51. · 0.61 Impact Factor
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ABSTRACT: Growing skull fractures are rare complications of severe closed head injury occurring almost exclusively in infants and children under the age of three. The reported incidence is between 0.05% and 0.6%. Two such cases were treated at our institution. Both cases presented with bulging mass and underlying skull defect two months after head injury. They received surgical treatment and achieved excellent results. Early diagnosis and surgical intervention are essential for these patients to prevent progressive brain damage. Therefore, close follow-up for patients at risk of developing growing skull fracture is necessary.
The Kaohsiung journal of medical sciences 04/1999; 15(3):175-81. · 0.61 Impact Factor
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ABSTRACT: Fourteen cases of shaken baby syndrome seen between 1993 to 1997 at the Kaohsiung Medical College Hospital were reviewed. The common clinical presentations were seizure, respiratory problem and disturbed consciousness. The signs and symptoms of this form of head trauma were nonspecific. The findings may mimic infection, intoxication, seizure disorder or metabolic abnormalities. The CT scan is the most common diagnostic tool in cases of suspected shaken baby syndrome. The common CT findings were acute subdural hematoma followed by chronic subdural hematoma and subarachnoid hemorrhage. One infant died due to delay in seeking medical help. Five patients sustained significant morbidity which included developmental delay, seizure, motor deficit and visual impairment. Early recognition and prompt treatment were key to the overall success of case management. The incidence of shaken baby syndrome can be reduced through public awareness and education of the parents not to shake the baby.
The Kaohsiung journal of medical sciences 02/1998; 14(2):112-6. · 0.61 Impact Factor
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ABSTRACT: We studied the electron microscopic features of the outer membrane of chronic subdural hematoma to explore the mechanism of growth of chronic subdural hematoma. Ultrastructurally, the outer membrane consisted of bundles of collagen fibrils and cellular elements such as fibroblasts, mast cells, migrating erythrocytes, platelets and eosinophils. A large number of proliferating macrocapillaries coursed among them. Such general characteristics of the endothelial cells with proliferating macrocapillaries as gap junctions and thinness or absence of the basement membrane suggested that they be very fragile and susceptible to bleeding. The number and extent of endothelial gap junctions indicated that they could account for most of the leakage not only into the tissue of the outer membrane but also into the hematoma cavity. The outer membranes had a prominent infiltration of eosinophils. Plasminogen secreted by the eosinophils inhibits the formation of platelet thrombus within the lumen and also dissolves fibrinoid substance, which reinforces fragile endothelial walls or edematous interstitium. These features possibly contribute to the recurring hemorrhage from the vessels in the outer membrane and the resultant enlargement of the hematoma.
The Kaohsiung journal of medical sciences 01/1998; 14(1):25-30. · 0.61 Impact Factor
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ABSTRACT: Extracranial diversion of cerebrospinal fluid in hydrocephalus using the currently available shunting system is often unsatisfactory. We have successfully treated four patients with non-communicating hydrocephalus, with no mortality or morbidity, using a flexible endoscope to perform third ventriculostomy. These patients remained shunt independent after treatment and have obtained long-term (minimum 42 months) stabilization. Flexible endoneurosurgical management is simple and safe, and allows in situ observation and performance of biopsies. Endoscopic third ventriculostomy is now our treatment of choice for non-communicating hydrocephalus.
Journal of the Formosan Medical Association 11/1997; 96(10):839-42. · 1.13 Impact Factor
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ABSTRACT: A 15-year-old male was admitted to our hospital with diabetes insipidus, headache and bitemporal hemianopia and a computed tomogram (CT) revealed an intra- and suprasellar tumor. Differential diagnosis between large intra- and suprasellar germinoma and pituitary adenomas is quite difficult based on CT. After comparing our case with past literature of reported cases of intrasellar and suprasellar germinoma, we found that an enhanced mass posterior to the pituitary gland on the midsagittal magnetic resonance imaging (MRI) and absence of the high signal intensity of the posterior lobe on T1-weighted MRI in patients with diabetes insipidus indicated germinoma rather than a pituitary adenoma. Transphenoid approach and appropriate radiotherapeutic management were administered with a good result.
The Kaohsiung journal of medical sciences 08/1997; 13(7):462-6. · 0.61 Impact Factor
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ABSTRACT: A 73-year-old man who had a huge calcified chronic subdural hematoma is reported. He developed progressive right hemiparesis and conscious disturbance. Computerized tomography demonstrated a huge subdural hematoma bordered by a calcified rim. A large osteoplastic craniotomy was performed and revealed approximately 300 grams of paste-like, muddy blood clot. The calcified outer membrane contained proliferating capillaries which was conceivably contributed to the leakage of blood. It is noteworthy that an active vascular proliferation was observed even in the healed tissue with calcification.
The Kaohsiung journal of medical sciences 05/1997; 13(4):272-6. · 0.61 Impact Factor
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ABSTRACT: Based on analysis of 5-year survival rates among 386 patients with carcinoma of the cervix treated between 1976 and 1984 at Yonsei University College of Medicine, high risk factors have been defined which identify patients with a poor prognosis when treated with radiation alone. Among patients with FIGO Stages I-II disease, lesions > or = 4 cm were indicative of a higher risk of treatment failure. Between 1984 and 1991, 39 patients with Stages I-II large cell squamous cancers > or = 4 cm in diameter were treated with radiation alone. Between 1984 and 1989, 19 comparable patients were treated with sequential chemotherapy consisting of two or three cycles of cisplatin at 100 mg/m2 and a 5-day infusion of 5-fluorouracil at 1000 mg/m2/24 hr. Between 1988 and 1991, 37 comparable patients were treated with concurrent radiation and one to six cycles of chemotherapy employing the same or equivalent drug and dose schedule. The radiation techniques, dose, and fractionation employed were similar in the three groups. The 30-month survival rate was 100, 89.5, and 79.5% (P < 0.05) following concurrent treatment, sequential treatment, and radiation alone, respectively. Response to chemotherapy administered in cycles was evaluated before instituting radiotherapy in the patients treated with sequential chemotherapy and radiation. In conclusion, the combination of radiotherapy and chemotherapy appeared superior to radiation alone, and the toxicity of combined modality therapy is manageable. Also concurrent chemotherapy may be slightly better than sequential chemotherapy and radiation, and given the lesser overall treatment time and expense, this has become the preferred mode of treatment in our institution.
Gynecologic Oncology 09/1993; 50(2):196-201. · 3.89 Impact Factor
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ABSTRACT: The 386 cases of invasive cervical carcinoma treated with radiotherapy alone were statistically analyzed to delineate the high risk factors (HRFs) associated with a significantly high treatment failure rate; they were (1) stages III-IV, (2) lesion greater than or equal to 4.0 cm, (3) small cell carcinoma or adenocarcinoma, (4) stages I-II with lesion greater than or equal to 4.0 cm, and (5) lymphographic evidence of nodal metastasis. Then, chemoradiotherapy (induction chemotherapy plus subsequent radiotherapy) was instituted to 113 invasive cervical carcinoma patients with at least one such HRF. Each patient received two to three cycles of induction chemotherapy at about 3-week intervals. For squamous cell carcinoma, cisplatin, 100 mg/m2 iv, was followed immediately by 5-fluorouracil, 1000 mg/m2, as a 24-hr iv infusion x 5 days. For adenocarcinoma, cisplatin, 70 mg/m2 iv, on Day 1 was followed by cytoxan, 250 mg/m2, on Day 2, and adriamycin, 45 mg/m2, on Day 3. Five-year survival of these patients according to each HRF, in the above order, was 69.1, 67.2, 68.1, 78.3, and 79.5% after chemoradiotherapy, all significantly higher than 57.4, 53.0, 54.5, 48.0, and 48.8% by radiotherapy alone. Drug toxicities such as leukopenia, hepatotoxicity, nephrotoxicity, and hypomagnesemia were seen in 46.5, 53.2, 47.1, and 55.4% of all cycles, respectively. The toxicities altered drug schedule in 191 (61.2%) ongoing induction chemotherapy cycles. Our cisplatin-based induction chemotherapy is considered an effective preradiotherapy adjunct that can reduce treatment failure in HRF-associated invasive cervical carcinoma.
Gynecologic Oncology 06/1991; 41(2):107-12. · 3.89 Impact Factor
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ABSTRACT: Two cases of sphenoid sinus aspergillosis underwent surgical intervention via the transsphenoidal approach to the sphenoid sinus cavity with good results in both cases. Adjunctive systemic antifungal therapy with amphotericin B was used in one case. The headache and visual disturbance improved postoperatively and no obvious neurological sequelae were encountered.
The Kaohsiung Journal of Medical Sciences 05/1990; 6(4):206-12. · 0.61 Impact Factor
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The Kaohsiung Journal of Medical Sciences 12/1987; 3(11):703-7. · 0.61 Impact Factor
