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1.
Nat Commun ; 12(1): 4062, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34210963

RESUMEN

Spin-valley locking in monolayer transition metal dichalcogenides has attracted enormous interest, since it offers potential for valleytronic and optoelectronic applications. Such an exotic electronic state has sparsely been seen in bulk materials. Here, we report spin-valley locking in a Dirac semimetal BaMnSb2. This is revealed by comprehensive studies using first principles calculations, tight-binding and effective model analyses, angle-resolved photoemission spectroscopy measurements. Moreover, this material also exhibits a stacked quantum Hall effect (QHE). The spin-valley degeneracy extracted from the QHE is close to 2. This result, together with the Landau level spin splitting, further confirms the spin-valley locking picture. In the extreme quantum limit, we also observed a plateau in the z-axis resistance, suggestive of a two-dimensional chiral surface state present in the quantum Hall state. These findings establish BaMnSb2 as a rare platform for exploring coupled spin and valley physics in bulk single crystals and accessing 3D interacting topological states.

2.
Sci Rep ; 7(1): 12061, 2017 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-28935891

RESUMEN

We present a comprehensive study of the crystal structure of the thin-film, ferromagnetic topological insulator (Bi, Sb)2-x V x Te3. The dissipationless quantum anomalous Hall edge states it manifests are of particular interest for spintronics, as a natural spin filter or pure spin source, and as qubits for topological quantum computing. For ranges typically used in experiments, we investigate the effect of doping, substrate choice and film thickness on the (Bi, Sb)2Te3 unit cell using high-resolution X-ray diffractometry. Scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy measurements provide local structural and interfacial information. We find that the unit cell is unaffected in-plane by vanadium doping changes, and remains unchanged over a thickness range of 4-10 quintuple layers (1 QL ≈ 1 nm). The in-plane lattice parameter (a) also remains the same in films grown on different substrate materials. However, out-of-plane the c-axis increases with the doping level and thicknesses >10 QL, and is potentially reduced in films grown on Si (1 1 1).

3.
Acta Neurochir (Wien) ; 146(6): 589-94: discussion 594, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15168227

RESUMEN

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.


Asunto(s)
Astrocitoma/cirugía , Epilepsia/etiología , Glioblastoma/cirugía , Complicaciones Posoperatorias/etiología , Neoplasias Supratentoriales/cirugía , Anciano , Astrocitoma/complicaciones , Astrocitoma/diagnóstico , Hemorragia Cerebral/complicaciones , Progresión de la Enfermedad , Femenino , Glioblastoma/complicaciones , Glioblastoma/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Análisis de Regresión , Estudios Retrospectivos , Factores de Riesgo , Neoplasias Supratentoriales/complicaciones , Neoplasias Supratentoriales/diagnóstico
4.
Surg Neurol ; 60(5): 402-6; discussion 406, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14572960

RESUMEN

BACKGROUND: By the use of conditional probabilities of survival, we studied the yearly survival rates for individual tumor survivors. METHODS: 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. RESULTS: 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%). CONCLUSIONS: 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.


Asunto(s)
Astrocitoma/mortalidad , Glioblastoma/mortalidad , Neoplasias Supratentoriales/mortalidad , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Estudios Retrospectivos , Análisis de Supervivencia , Tasa de Supervivencia , Taiwán/epidemiología
5.
Acta Neurochir (Wien) ; 144(2): 189-93; discussion 193, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11862520

RESUMEN

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.


Asunto(s)
Antiarrítmicos/farmacología , Isquemia Encefálica/complicaciones , Infarto Cerebral/complicaciones , Mexiletine/farmacología , Daño por Reperfusión/prevención & control , Accidente Cerebrovascular/complicaciones , Animales , Edema Encefálico , Arterias Carótidas/patología , Arterias Cerebrales/patología , Infarto Cerebral/tratamiento farmacológico , Relación Dosis-Respuesta a Droga , Masculino , Ratas , Ratas Sprague-Dawley , Accidente Cerebrovascular/tratamiento farmacológico
6.
J Clin Neurosci ; 8(5): 426-9, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11535010

RESUMEN

To evaluate the incidence and influencing factors related to preoperative and postoperative seizures, a retrospective analysis was performed in 190 patients with astrocytic tumours. Preoperative seizures occurred in 50 (26%) patients and 27 (54%) of the m had recurrent seizures. Late-onset seizures developed after craniotomy in 11 (8%) of 140 patients. Seizures at presentation were significantly correlated with age at diagnosis (P=0.0204) and pathological grade of tumour (P=0.0040). The patients aged less than 40 years had a high risk of seizures at presentation (odds ratio=3.076, P=0.0134). Postoperative seizures were significantly associated with the presence of preoperative seizures (P<0.0001), type or duration of preoperative seizures (P<0.0001, P<0.0001, respectively) and serum level of anticonvulsant drug (P=0.0068). However, only the presence of preoperative seizures had a potential for prediction of postoperative seizures when evaluated by logistic regression model (odds ratio=20.859, P=0.0001). Fifty-nine percent of patients with recurrent seizures and 64% of patients with late-onset seizures had seizures which occurred within 6 months after craniotomy. Despite therapeutic anticonvulsant levels, most postoperative seizures were associated with tumour recurrence or haemorrhage. Postoperative seizures commonly occurred relatively soon after craniotomy and prophylactic anticonvulsants should be given. In patients with postoperative seizures, particularly in the presence of therapeutic anticonvulsant level, brain computed tomography should be performed to exclude tumour recurrence or haemorrhage.


Asunto(s)
Astrocitoma/epidemiología , Neoplasias Encefálicas/epidemiología , Epilepsia/epidemiología , Complicaciones Posoperatorias/epidemiología , Adolescente , Adulto , Anciano , Astrocitoma/cirugía , Neoplasias Encefálicas/cirugía , Niño , Preescolar , Craneotomía , Femenino , Humanos , Incidencia , Lactante , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
7.
Neurosurgery ; 49(2): 422-7; discussion 427-9, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11504119

RESUMEN

OBJECTIVE: Endothelin-mediated vasoconstriction has been implicated in the pathophysiology of cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH). Endothelin-1, the most potent vasoconstrictor peptide of the endothelin family, is synthesized initially as a large prepropeptide that requires multiple steps of post-translational processing for activation. The final step of this processing involves the proteolytic cleavage of a relatively inactive precursor, big endothelin-1, by the metalloprotease endothelin-converting enzyme. Previous findings have demonstrated that intravenous bolus injections of an endothelin-converting enzyme inhibitor (CGS 26303) administered twice daily can prevent and reverse arterial narrowing in a rabbit model of SAH. However, attenuation of vasospastic response was incomplete and required relatively high doses to be effective in reversing vasospasm. Therefore, the present study evaluated an alternative protocol for administration of CGS 26303 to optimize the antispastic influence of this compound. METHODS: Continuous intravenous infusion of CGS 26303 at doses of 2.4, 8.0, or 24.0 mg/kg/d was initiated either 1 hour (prevention paradigm) or 24 hours (reversal paradigm) after experimental SAH in New Zealand White rabbits. All animals were killed by perfusion-fixation 48 hours after SAH. Basilar arteries were then removed and sectioned, and their cross-sectional areas were measured by use of computer-assisted video microscopy. RESULTS: Continuous intravenous infusion of CGS 26303 attenuated SAH-induced cerebral vasospasm in a dose-dependent manner in both the prevention and the reversal groups. These effects achieved statistical significance at all doses as compared with the SAH-only or SAH-plus-vehicle groups. Furthermore, the attenuation of vasospasm after continuous infusion of CGS 26303 was more efficacious than that obtained with bolus injections. CONCLUSION: These findings provide further support for the use of endothelin-converting enzyme inhibition as a therapeutic strategy for reduction of cerebral vasospasm, and they also support the effectiveness of this strategy even when initiated after arterial narrowing has been established. The findings also indicate that continuous intravenous infusion of CGS 26303 is a more effective approach for attenuation of vasospasm than bolus intravenous administration.


Asunto(s)
Ácido Aspártico Endopeptidasas/antagonistas & inhibidores , Organofosfonatos/uso terapéutico , Inhibidores de Proteasas/uso terapéutico , Hemorragia Subaracnoidea/complicaciones , Tetrazoles/uso terapéutico , Vasoespasmo Intracraneal/tratamiento farmacológico , Vasoespasmo Intracraneal/prevención & control , Animales , Enzimas Convertidoras de Endotelina , Infusiones Intravenosas , Masculino , Metaloendopeptidasas , Conejos , Vasoespasmo Intracraneal/etiología
8.
Surg Neurol ; 55(5): 297-301, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11516473

RESUMEN

BACKGROUND: Cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) remains a major complication in patients suffering from SAH. In our previous study, we reported that stimulating vascular K(+) channel activity prevented the development of cerebral vasospasm. Recent evidence indicates that glyceryl nonivamide (GLNVA), a capsaicin derivative, has a vasorelaxant effect on the aortic vascular smooth muscle due to the release of coronary calcitonin gene-related peptide, which in turn stimulates K(+) channel opening. The purpose of the present study was to examine the preventive effects of GLNVA on vasospasm. METHODS: New Zealand white rabbits were subjected to experimental SAH by injecting autologous blood into the cisterna magna. GLNVA or vehicle was injected intrathecally immediately after the induction of SAH. All animals were killed by perfusion-fixation at 48 hours after SAH. The basilar arteries were removed and sectioned, and their cross-sectional areas were measured. RESULTS: The average cross-sectional areas of basilar arteries were reduced by 69% and 71% in the SAH only and SAH plus vehicle groups, respectively, when compared with the healthy controls. After treatment with 0.35, 1.75, and 3.5 mg/kg GLNVA in rabbits subjected to SAH the average cross-sectional area was decreased by 46%, 12% and 2%, respectively, when compared with the healthy controls. The protective effect of GLNVA achieved statistical significance at all dosages. Morphologically, corrugation of the internal elastic lamina of vessels was often observed in the vehicle-treated group, but was not prominent in the GLNVA-treated groups or healthy controls. CONCLUSION: The findings showed that GLNVA dose-dependently attenuated cerebral vasospasm after SAH in the rabbit. These results suggest that intrathecal administration of GLNVA could be an effective strategy for preventing cerebral vasospasm after SAH.


Asunto(s)
Capsaicina/farmacología , Glicerol/farmacología , Hemorragia Subaracnoidea/complicaciones , Vasoespasmo Intracraneal/tratamiento farmacológico , Vasoespasmo Intracraneal/prevención & control , Animales , Capsaicina/análogos & derivados , Capsaicina/uso terapéutico , Modelos Animales de Enfermedad , Glicerol/análogos & derivados , Glicerol/uso terapéutico , Masculino , Conejos , Vasoespasmo Intracraneal/etiología
9.
Kaohsiung J Med Sci ; 16(7): 339-44, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11079292

RESUMEN

From June 1986 to September 1996, 56(30%) patients with invasive pituitary macroadenoma were studied retrospectively. We compared the clinical and endocrinological characteristics, neuroimaging findings, and surgical outcome of these patients in a period of follow up of 5 years. Twenty-one patients (38%) were found to have a prolactinoma, 8 patients (14%) had a GH-producing adenoma, and 27 patients (48%) had non-functional tumors. Pituitary apoplexy was found in 16 cases (29%). Their age ranged from 15 to 72 years and no sex difference (F:M = 27:29) was found. According to Hardy's classification, all the 56 tumors were invasive pituitary macroadenoma, of a tumor size more than 10 mm with sellar floor erosion partially or diffusely or paracarvenous sinus invasion. Those tumors were divided into grade III (tumor causing localized perforation of the sellar floor), and IV (tumor destroying entire sellar floor diffusely); the tumors were further subdivided into stage C (3rd ventricle grossly displaced), D (intracranial intradural extension) and E (tumors invading the cavernous sinus through the lateral dural envelope of the sellar). Eight out of 56 tumors belonged to grade III stage C, 18 tumors were grade III stage D, 8 tumors were grade IV stage D, and the other 22 were grade IV stage E. Fifty-one patients received transsphenoidal craniectomy for tumor removal, one patient took subfrontal craniotomy only and 4 cases received both. Most patients improved significantly in visual field and general quality of life after surgery. In this study, it was concluded that: 1) surgical intervention as quick as possible was proven advantageous, especially in patients with an invasive macroadenoma; 2) in cases with invasive pituitary macroadenomas, the patients, with grade III and IV tumors, had a longer symptom-free interval than those who refused surgical intervention and radiotherapy with the same grade tumor; 3) to achieve satisfactory late results, multidisciplinary treatment was necessary: post-operative radiotherapy ranging from 4500 to 6500 rads was done in 50 patients, endocrine therapy in 52 patients and adjunct bromocriptine treatment was done in 13 patients with prolactinomas; 4) symptomatic recurrence or elevated postoperative hormone levels occurred in 20(35%) cases. There was a high incidence of recurrence in 6(6/20) GH-secreting tumors, and in 8(8/20) prolactinomas with preoperative prolactin levels more than 200 eta g/dl.


Asunto(s)
Adenoma/terapia , Neoplasias Hipofisarias/terapia , Adenoma/patología , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Hipofisarias/patología , Estudios Retrospectivos
10.
J Cardiovasc Pharmacol ; 36(5 Suppl 1): S160-2, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11078366

RESUMEN

The effects of CGS 26303, a dual inhibitor of endothelin-converting enzyme (ECE) and neutral endopeptidase 24.11, and its prodrug, CGS 26393, on bovine cerebrovascular endothelial cells stimulated with hemolysate were investigated. Upon incubation with hemolysate for 48 h, cell density was significantly decreased, with concomitant increases in endothelin-1 (ET-1) (42 vs 11 pg/ml) and big ET-1 (79 vs 27 pg/ml) levels in culture medium when compared with controls. Simultaneous addition of CGS 26303 (10 and 100 microM) and hemolysate protected against cell loss and decreased cellular vacuolization caused by hemolysate. The levels of ET-1 and big ET-1 in the culture medium were decreased dose-dependently. More drastically, pretreatment with 100 microM CGS 26303 for 30 min decreased the production of ET-1 and big ET-1 by 94% and 87%, respectively, when compared with the untreated control. However, treatment with CGS 26393 was much less effective. These results suggest that suppression of ET-1 production by ECE inhibitors may prove to be efficacious for the treatment of hemolysate-induced cytotoxicity on cerebral endothelial cells.


Asunto(s)
Ácido Aspártico Endopeptidasas/antagonistas & inhibidores , Endotelina-1/biosíntesis , Endotelio Vascular/efectos de los fármacos , Organofosfonatos/farmacología , Inhibidores de Proteasas/farmacología , Tetrazoles/farmacología , Animales , Bovinos , Células Cultivadas , Arterias Cerebrales/efectos de los fármacos , Arterias Cerebrales/metabolismo , Relación Dosis-Respuesta a Droga , Enzimas Convertidoras de Endotelina , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Metaloendopeptidasas
11.
Kaohsiung J Med Sci ; 15(2): 75-9, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10089716

RESUMEN

We retrospectively study 17 cases (total cases 197), receiving surgery at Kaohsiung Medical College Hospital, which are proved to be subacute pituitary apoplexy via preoperative computerized tomograms, magnetic resonance imagings, operative findings and pathological proof. Fourteen patients had headache; 15 cases were with visual disturbance including visual defect, blindness. One case was found incidentally to have a cerebral vascular attack. None of these cases received bromocriptine. Preoperative computerized tomograms (CT) aided the initial diagnosis and magnetic resonance imaging (MRI) is preferred for radiological investigation in displaying the metabolic products of hemorrhage within the pituitary tumors. Operative findings revealed xanthochromic fluid with liquid-like tumor debris or chocolate-like content. All these patients received hormone supplement when pituitary apoplexy was highly suspected.


Asunto(s)
Apoplejia Hipofisaria/diagnóstico , Enfermedad Aguda , Adolescente , Adulto , Anciano , Femenino , Hormonas/análisis , Humanos , Masculino , Persona de Mediana Edad , Apoplejia Hipofisaria/terapia
12.
Kaohsiung J Med Sci ; 15(12): 691-6, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10645130

RESUMEN

Pituitary adenomas account for less than 6% of all intracranial tumors in adolescence. Between November 1987 and October 1996, 8 patients were treated by transsphenoidal resection at Kaohsiung Medical College Hospital. This series included 4 girls and 4 boys with ages ranging from 14 to 19 years. Symptoms reflecting endocrine dysfunction such as scanty pubic hairs in males and amenorrhea in females, were more often found than neurological problems in all adolescents at presentation. Macroadenoma occurred in five of our eight cases (62%) of adolescent pituitary adenoma. In one case (12%), the tumor was plurihormonal tumor. Long-term follow-up (mean 4.5 +/- 2.7 years) revealed the majority of patients had good endocrine function. Significant operative morbidity included steroid-induced psychosis in one patient and transient diabetes insipidus in three, which resolved in all three within two weeks. Our study showed that 1) pituitary tumors in children were uncommon, and when they occurred they were frequently large and invasive; 2) the endocrine disturbance caused by pituitary adenomas alerted the patients to seek medical help more often than neurological deficit; 3) in adolescence, almost all pituitary adenomas were functioning; nonfunctioning pituitary adenomas were rare in adolescence; and 4) transsphenoidal surgery was feasible and safe in adolescence, even with poor pneumatization of the sphenoid sinus, which remains controversial in the literature.


Asunto(s)
Adenoma/cirugía , Neoplasias Hipofisarias/cirugía , Adenoma/complicaciones , Adenoma/fisiopatología , Adolescente , Hormona Adrenocorticotrópica/metabolismo , Adulto , Síndrome de Cushing/etiología , Femenino , Humanos , Masculino , Neoplasias Hipofisarias/complicaciones , Neoplasias Hipofisarias/fisiopatología
13.
Kaohsiung J Med Sci ; 15(11): 659-64, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10630063

RESUMEN

The Chiari malformations are a group of central nervous system defects that involve the posterior cranial fossa. The clinical complaints range from headache, sensory changes, vertigo, ataxia, and imbalance to hearing loss. In patients with Chiari malformation, only those with type I malformation were born grossly normal, the neurological dysfunction developing gradually as they grew up, which spurred our interest. From August 1990 to September 1998, seven patients received surgical intervention at Kaohsiung Medical College Hospital under the impression of Chiari malformations. There were 4 males and 3 females, with age ranging from 7 years to 41 years. All these patients were diagnosed via magnetic resonance imaging and surgical findings revealed a hypoplasic vermis. Among them, 4(57%) were cranial nerve plasy, 2(29%) nystagmus, 6(100%) syringomyelia, 7(100%) scoliosis and one (14%) with hydrocephalus. Cerebellar ataxia and upper limbs weakness was noted in 5(71%) patients. Our surgical interventions included suboccipital craniectomy and dural opening(7/7), C1 posterior arch decompression (7/7), C4,5 laminectomy (1/7), and syringostomy(4/7). There was one mortality in a 41 y/o male with progressively lower cranial nerve(V, VII, IX) impairment as well as poor lung compliance. Other patients improved in their symptoms after follow-up periods of 6 months to 6 years. Our study shows that 1) surgical decompression was indicated in all patients with brain stem and lower cranial nerve dysfunction as well as central cord syndrome caused by syringomyelia; 2) a better result was achieved in those patients who received adequate nervous system decompression; and 3) much attention should be payed to cases with lower cranial nerves XI, X, XII impairment, because complications such as choking and aspiration pneumonia can happen.


Asunto(s)
Malformación de Arnold-Chiari/cirugía , Adolescente , Adulto , Malformación de Arnold-Chiari/diagnóstico , Niño , Femenino , Humanos , Masculino
14.
Kaohsiung J Med Sci ; 14(4): 242-6, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9589619

RESUMEN

We describe a 53-year-old mother and a her 34-year-old son who suffered from spontaneous subarachnoid hemorrhage (SAH) and/or intracerebral hemorrhage due to a ruptured intracranial aneurysm. Diagnosis of the intracranial aneurysm was made by CT scan of the brain, and cerebral angiography. These two cases received surgical intervention and returned to their previous social activity after discharge, even though the mother had arrived in a comatose condition. The literature is reviewed and the characteristic expressions of familial intracranial aneurysms are described. The etiology of cerebral aneurysms is still uncertain but it is likely multifactorial. For the 176 patients with intracranial aneurysm(s) treated at Kaohsiung Medical College Hospital, the mean age at diagnosis was 51.9 years and these aneurysms were distributed mainly at the internal carotid artery (43.8%) and the anterior communicating artery (33.5%). The familial aneurysms tend to rupture at a younger age, occur less often at the anterior communicating artery and more often at the internal carotid artery and the middle cerebral artery as compared with that of non-familial aneurysms. In siblings, aneurysms occur at identical sites or at mirror sites and rupture within the same decade of life twice as frequently as expected in non-familial aneurysm cases. The familial aggregation of intracranial aneurysms and the above characteristic expressions suggest that heredity may play a role in some familial aneurysms. The pattern of inheritance, however, has not been established. Screening examinations and the treatment of unruptured intracranial aneurysms in asymptomatic relatives of the familial cases are also discussed.


Asunto(s)
Aneurisma Intracraneal/genética , Adulto , Femenino , Humanos , Aneurisma Intracraneal/diagnóstico , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Hemorragia Subaracnoidea/diagnóstico , Hemorragia Subaracnoidea/genética
15.
Kaohsiung J Med Sci ; 14(1): 1-5, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9519682

RESUMEN

From 1986 to 1996, 187 patients with pituitary adenoma were diagnosed and received surgery at Kaohsiung Medical College Hospital. Of which, 29 patients older than 60 years were retrospectively studied. Their initial clinical symptoms, pathological findings, immunoperoxidase staining, electronic microscopic findings and hormone levels were retrospectively recorded. We found that the old patients more often suffered from the neurological deficit such as headache and visual problems rather than endocrine of the tumors cells are compared, and fewer cells and nuclei are found in the older group than that in the younger group. The secretary granules in functioning tumors especially prolactinomas in old-aged patients are larger than those in the young patients. The tumor cells in the old-aged patients have fewer subcellular organelles and secretary granules but have large secretary granules. It is concluded that: (1) transsphenoidal surgery is feasible and safe in this age group; (2) plurihormonal tumors occur more frequently in old-age than young patients; (3) clinically endocrine-inactive pituitary adenomas occur more often in old-aged; (4) pituitary adenomas in old-aged cause neurological deficit more frequently than endocrine disturbance.


Asunto(s)
Adenoma/ultraestructura , Neoplasias Hipofisarias/ultraestructura , Adenoma/metabolismo , Hormona Adrenocorticotrópica/metabolismo , Adulto , Factores de Edad , Anciano , Gránulos Citoplasmáticos/ultraestructura , Femenino , Humanos , Masculino , Neoplasias Hipofisarias/metabolismo , Prolactina/sangre
16.
Kaohsiung J Med Sci ; 13(8): 516-9, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9311204

RESUMEN

Herein, we are describing an unusual case suffering from a left anterior cerebral artery aneurysm (A1). Both the anterior cerebral arteries were supplied by the left internal carotid artery as was found in digital substraction angiography (DSA) preoperatively. The postoperative angiograms revealed that left anterior cerebral artery was supplied from the left internal carotid artery and the right anterior cerebral artery by the right internal carotid artery respectively. This finding of cerebral angiograms is interesting and rarely mentioned in the literature. Its hemodynamic change and pathogenesis were unclear and different to that of the coronary circulation, ischemic change of gut and skeletal muscle. The causes may include: 1) vasospasm at the anterior communicating artery after manipulation at surgery; 2) desiccation or shrivelling the adjacent artery by intraoperative electrocoagulation; 3) occlusion the anterior communicating artery by the wing of clip. 4) the deprivation of the blood flow from the left internal carotid artery after totally or partially narrowing left A1 by an aneurysm clip. The redistribution of blood volume in the previously hypoplastic right anterior cerebral artery and decreased caliber of the left anterior cerebral artery (A1) are likely playing a role in this case.


Asunto(s)
Arterias Cerebrales/cirugía , Circulación Cerebrovascular/fisiología , Aneurisma Intracraneal/cirugía , Angiografía Cerebral , Arterias Cerebrales/diagnóstico por imagen , Femenino , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Persona de Mediana Edad , Pronóstico , Tomografía Computarizada por Rayos X
17.
Kaohsiung J Med Sci ; 13(7): 457-61, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9260467

RESUMEN

Despite modern medical advances, the morbidity and mortality rates associated with spinal epidural abscess remain significant, and the diagnosis is elusive. The incidence of spinal epidural abscess is approximately one to two cases per 10,000 among all patients admitted to hospitals. The symptoms of spinal epidural abscess are varied but include lower back pain, fever, local tenderness and neurological deficit especially in such high risk groups as patients with diabetes, intravenous drug abuse, chronic renal failure, alcoholism, liver disease and immunocompromization. Accumulation of data is difficult in that many physicians will never see a case during their careers. Herein, we present a case with lower back pain associated with both lower legs weakness. His abdomenon CT revealed retroperitonium and right perirenal abscess. External drainage as well as antibiotic treatment was done immediately. However, the lower legs weakness became severe and a lumbar spine MRI revealed T11-L4 epidural abscesses and L2-3 intervertebral space pus formation. Then, the patient was transfered to our Neurosurgical Ward for further treatment. His postoperative condition improved in both lower legs. This case report is to enhance the recognition and treatment of spinal epidural abscess, a rare affliction.


Asunto(s)
Absceso/diagnóstico , Enfermedades de la Columna Vertebral/diagnóstico , Absceso/terapia , Espacio Epidural , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Columna Vertebral/terapia
18.
Kaohsiung J Med Sci ; 13(11): 685-9, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9425868

RESUMEN

Fungus infection of the sinunasal tract usually follows a slow, nonaggressive course. With massive bone destruction or along the foramen of skullbase, the disease may extend outside the confines of the sinunasal tract even into intracranum, causing cerebral epidural, subdural and intracerebral abscess. Recently, allergic fungal sinusitis (AFS) has been a described disease entity, usually occurring in immunocomponent individuals. Early reports cited Aspergillus as the causative organism. It is now recognized that the dematiaceous fungi, including Bipolaris, Culvularia, Exserohilum, and Alternaria are associated with AFS. The disease typically follows a slow, mild course and dose not invade tissue, although pressure in the sinus can eventually cause expansion and erosion of the sinus walls. We report a case who was presented with right facial swelling and numbness, right vision loss, right hearing loss as well as deficit in cranial nerve III, IV, V, VI. A gangrene was found in right upper concha. A biopsy was done and fungal hyphae was noted. The brain MRI revealed right temperal tip abscess; he was then transfered to our ward for further surgeical treatment. The pathological findings revealed Aspergillus. A new diagnostic entity, "skull base allergical fungal sinusitis" (SBAFS) as issued, could corporate the histological diagnostic criteria and the computed tomography of bone erosion in this case. Biopsy in the sinus and the brain is necessary to rule out fungus or tumor invasion. The awareness and corporation between otolaryngologists, ophthalmologists, and neurosurgeone with the disease can avoid delayed diagnosis and promote early treatment.


Asunto(s)
Aspergilosis/complicaciones , Absceso Encefálico/etiología , Hipersensibilidad/complicaciones , Sinusitis/complicaciones , Adulto , Humanos , Masculino
19.
Kaohsiung J Med Sci ; 13(9): 578-82, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9348737

RESUMEN

Cranial epidural abscesses are unusual in neurosurgical practice. Mostly they are secondary to skull bone osteomyelitis of foreign body implantation as a result of trauma, or infection of paranasal sinus, otitis, and mastoiditis in adults or late adolescents. The purulent inflammatory process of the epidural abscess, thrombophlebitis of the venous drainage, septic thrombosis, direct extension into the orbit, carvenous sinus, superior orbital fissure give the epidural abscess a high mortality and morbidity. We present an interesting case, who has had psychiatric symptoms such as bizarre behavior, auditory and visual hallucination for about two years. Incidental brain computed tomograms, to exclude the organic-somatic disorder, revealed a huge brain abscess. Emergent surgical intervention was carried out and the episodes of talking to himself and auditory hallucination subsided. The removal of the epidural abscess eliminated the symptoms and cured the patient. All the right amygdata, entorhinal area, cingulate gyrus, hippocampus and parahippocampal gyrus of this patient were compressed by the huge abscess. All these structures belonged to limbic system. Diseases involving the limb system may cause emotional disturbances, such as delusions, illusions and hallucinations, emotional lability, pathological laughing and crying, rage reaction and aggression, apathy and placidity, even endogenous fear, anxiety, depression and euphoria. Dramatic improvement of the patient was found after surgical removal of the abscess. We highlight this interesting case for it will undoubtedly bring together a large cooperation of psychiatrists, neurologists and neurosurgeons.


Asunto(s)
Absceso/complicaciones , Trastornos Mentales/etiología , Enfermedades de la Médula Espinal/complicaciones , Adulto , Humanos , Masculino
20.
Gaoxiong Yi Xue Ke Xue Za Zhi ; 11(11): 626-32, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7490796

RESUMEN

Diaphragmatic elevation after cardiac surgery may result in compromized post operative respiratory function, prolonged ventilator use, longer intensive care unit (ICU) stays, poor quality of life and even mortality. 200 patients receiving open-heart surgery during the two years from October 1990 to October 1992 were studied retrospectively. 26 patients developed postoperative diaphragmatic elevation (Group 2). On the other hand, 174 patients did not (Group 1). The mean age of Group 1 (37.3 +/- 20.0 years) was younger than that of Group 2 (57.4 +/- 9.1 years), P < 0.0001. The mean aortic cross-clamp time was 70.1 +/- 38.1 minutes in Group 1. On the other hand, Group 2 had a longer crossclamp time (84.5 +/- 31.3 Minutes), p < 0.03. Our study revealed that the patients who suffered post operative diaphragmatic dysfunction were older and had a longer aortic crossclamp time than the patients who did not.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/efectos adversos , Diafragma/fisiopatología , Complicaciones Posoperatorias/etiología , Adolescente , Adulto , Anciano , Niño , Preescolar , Frío/efectos adversos , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Nervio Frénico/fisiopatología , Estudios Retrospectivos
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