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Biomedical subjects

Nobusuke Tsuzuki

Publications and source records attributed to Nobusuke Tsuzuki.

18 recordsLinked to original sources
PubMed2006

Subarachnoid clot distribution in anterior wall saccular aneurysms of the internal carotid artery.

Anterior wall aneurysms of the internal carotid artery (AWAICA) are relatively uncommon. We investigated the distribution of the subarachnoid clot on computerized tomography (CT) scans in patients with ruptured AWAICA and compared the findings with those in patients with internal carotid artery aneurysms (ICAA) at other sites. Twenty-six ruptured ICAA patients were included in this study. Four (15.4%) of these had an AWAICA and 22 had an ICAA at other sites. Three of the 4 patients with AWAICA had an ordinary 'saccular type' aneurysm and the other had a 'blood blister-like' aneurysm. In all three patients with a 'saccular type' AWAICA, accumulation of the subarachnoid clot in the olfactory sulcus was noted on CT scan. In the patient with a 'blood blister-like' aneurysm and in 22 patients with ICAA at other sites, there were no specific correlations between focal accumulations of the subarachnoid clot and aneurysm location. The accumulation of subarachnoid clot in the olfactory sulcus on CT scan may suggest a ruptured 'saccular type' AWAICA.

Aneurysm↗
PubMed2006

Non-bifurcating cervical carotid artery.

Three cases of an extremely rare anomaly of the carotid artery are described herein. In these patients, the common carotid arteries, without bifurcation in the cervical portion, supplied multiple arterial branches, which are more commonly branches of the external carotid artery. The non-bifurcating carotid artery continued into the cranium as a normal internal carotid artery. This anomaly can be attributed to a maldevelopment of the vascular network during embryogenesis.

Aged↗
PubMed2004

Normal pressure hydrocephalus manifesting as transient prosopagnosia, topographical disorientation, and visual objective agnosia.

Usually, dementia, gait disturbance and urinary incontinence are an integral part of the clinical presentation of normal pressure hydrocephalus (NPH). However, NPH with transient visual cognitive disorders has not been reported previously. We herein describe an extremely rare case of NPH that presented with transient visual cognitive disorders and long lasting visual memory disturbances that subsided after CSF shunting. A 38-years-old man developed transient prosopagnosia, topographical disorientation, color vision disturbance, and visual objective agnosia that progressed over 5 years. Magnetic resonance images showed ventriculomegaly with ischemic lesions in the paraventricular deep white matter. ECD-SPECT showed a reduction of the cerebral blood flow (CBF) in the periventricular deep white matter. Three months after CSF shunting, the radiological findings normalized with dramatic improvement of the extremely rare symptoms.

Adult↗
PubMed2004

Gender disparities in serum electrolytes levels after subarachnoid hemorrhage.

We retrospectively studied 133 patients with subarachnoid hemorrhage (SAH) to assess whether there was any gender disparity in serum electrolytes levels throughout the clinical course. Serum concentrations of sodium and potassium were measured in all patients, while catecholamines or antidiuretic hormone were assessed in a number of cases. Female SAH-patients had lower potassium level (3.29 +/- 0.47 mEq/L) than did male patients (3.68 +/-0.38) on the first day of SAH. This gender disparity continued to the beginning of the chronic phase and disappeared several months later. Mean serum sodium level was lower in the male group than in the female group throughout the clinical course. Mean serum levels of adrenaline and antidiuretic hormone were characterized by their prominent high value on the first day. Serum potassium levels were inversely related to serum levels of catecholamines, especially adrenaline, during the acute and subacute phases, particularly on the first day.

Adult↗
PubMed2004

Focal brain edema and natriuretic peptides in patients with subarachnoid hemorrhage.

The present study was designed to assess the relationship between the presence of focal brain aedema and serum concentrations of atrial natriuretic peptide (ANP) or brain natriuretic peptide (BNP) in patients with subarachnoid haemorrhage (SAH). Serum levels of ANP and BNP were measured at six different time periods (Day 1, 2, 3, 4 to 7, 8 to 14, and 15 to 25) in 61 SAH-patients. Focal brain aedema, which was caused by an intracerebral haematoma associated with SAH or surgical complications, was found in eight SAH-patients by means of consecutive CT scans. The mean serum ANP and BNP levels in patients with focal brain aedema were significantly higher than those in patients without focal brain aedema between Days 4 and 14. These findings suggest that focal brain aedema may have some role in the pathogenesis of an excessive secretion of ANP and BNP during the subacute phase of SAH.

Adult↗
PubMed2003

Nuclear accumulation of basic fibroblast growth factor in human astrocytic tumors.

BACKGROUND: The authors recently reported that nuclear accumulation of basic fibroblast growth factor (bFGF) demonstrated a significant correlation with recurrence of pituitary adenomas. The current study sought to determine whether nuclear bFGF accumulation was a predictor of survival in patients with astrocytic tumors. METHODS: The authors examined 52 patients with primary astrocytic tumors. Immunohistochemical assays for bFGF, fibroblast growth factor receptor 1 (FGFR1), and proliferating cell nuclear antigen were performed. Immunoreactivity of bFGF in nuclei was recorded in terms of the bFGF nuclear index (NI), which was calculated as the percentage of tumor cells with nuclear immunoreactivity. Western blot analysis of bFGF in nuclear fractions was performed. RESULTS: The bFGF NI had a mean value of 35.1% and was < 30% (low NI) in 27 patients and >or= 30% (high NI) in 25 patients. In all cases, FGFR1 immunoreactivity was observed in the cytoplasm but not in the nucleus. Western blot analysis indicated that the nuclear fractions from tumor specimens with high NI contained high-molecular-weight bFGF. Univariate analyses showed that age, tumor histology, gender, and bFGF NI were significantly correlated with patient survival. Multivariate analyses demonstrated that NI had the greatest influence (P = 0.0073) on survival rate, compared with age (P = 0.0083) and gender (P = 0.0492). Compared with low NI, high NI was associated with a relative risk of 3.292. CONCLUSIONS: The findings of the current study suggest that bFGF NI may be a useful predictor of survival in patients with astrocytic tumors.

Adult↗
PubMed2003

Multivariate analysis of risk factors for QT prolongation following subarachnoid hemorrhage.

BACKGROUND: Subarachnoid hemorrhage (SAH) often causes a prolongation of the corrected QT (QTc) interval during the acute phase. The aim of the present study was to examine independent risk factors for QTc prolongation in patients with SAH by means of multivariate analysis. METHOD: We studied 100 patients who were admitted within 24 hours after onset of SAH. Standard 12-lead electrocardiography (ECG) was performed immediately after admission. QT intervals were measured from the ECG and were corrected for heart rate using the Bazett formula. We measured serum levels of sodium, potassium, calcium, adrenaline (epinephrine), noradrenaline (norepinephrine), dopamine, antidiuretic hormone, and glucose. RESULTS: The average QTc interval was 466 +/- 46 ms. Patients were categorized into two groups based on the QTc interval, with a cutoff line of 470 ms. Univariate analyses showed significant relations between categories of QTc interval, and sex and serum concentrations of potassium, calcium, or glucose. Multivariate analyses showed that female sex and hypokalemia were independent risk factors for severe QTc prolongation. Hypokalemia (<3.5 mmol/l) was associated with a relative risk of 4.53 for severe QTc prolongation as compared with normokalemia, while the relative risk associated with female sex was 4.45 as compared with male sex. There was a significant inverse correlation between serum potassium levels and QTc intervals among female patients. CONCLUSION: These findings suggest that female sex and hypokalemia are independent risk factors for severe QTc prolongation in patients with SAH.

Adult↗
PubMed2003

The association of the expression of vascular endothelial growth factor with the cystic component and haemorrhage in pituitary adenoma.

Vascular endothelial growth factor (VEGF) is known to be a mediator of angiogenesis and vascular permeability. A cystic component and haemorrhage are often found in pituitary adenomas. We assessed the VEGF expression based on immunohistochemical examinations in 48 pituitary adenomas. All the adenomas showed some VEGF immunoreactivity mainly in the cytoplasm of tumour cells. Of the 48 adenoma-cases, 16 cases had a strong VEGF immunoreactivity, 26 cases had a moderate one, and 6 cases had a weak one. On the MR images, a cystic component was found in 16 cases (33.3%), and a haemorrhage was found in 18 cases (37.5%). The VEGF immunoreactivity had a significant relationship with the cystic component but not the haemorrhage, size, recurrence, or HE classification. These findings suggest that VEGF plays any potential role in the pathogenesis of cystic formation in pituitary adenomas.

Adolescent↗
PubMed2002

Subcellular localization of basic fibroblast growth factor and fibroblast growth factor receptor 1 in pituitary adenomas.

The aim of this study was to assess the subcellular localization of basic fibroblast growth factor (bFGF) and fibroblast growth factor receptor 1 (FGFR1) in pituitary adenomas. We studied 61 patients who had primary pituitary adenomas and underwent operation. The immunohistochemistry for bFGF, FGFR1, and MIB-1 was examined in paraffin-embedded tissues. The bFGF immunoreactivity in the nucleus was recorded as the bFGF nuclear index, which was calculated as the percentage of tumor cells with the bFGF immunoreactivity in the nuclei when more than 1000 tumor cells were examined. Recurrent adenomas were found in 7 patients during follow-up periods ranging from 8 to 134 months (mean, 57.2). The recurrent adenomas had significantly larger mean bFGF nuclear indices (74.8 +/- 28.8%) than the nonrecurrent adenomas (25.4 +/- 32.1%, P = 0.0003). The bFGF nuclear index also correlated significantly with the maximum tumor diameters and the invasiveness to the cavernous sinuses (Knosp grade) in the adenomas. The cytoplasmic FGFR1 immunoreactivity was inversely correlated (P < 0.02) with maximum tumor diameter. Neither cytoplasmic bFGF, cytoplasmic FGFR1, nor MIB-1 staining index showed any relationship with the recurrence of pituitary adenomas. These findings suggest that the nuclear accumulation of bFGF plays an important role in the progression of pituitary adenomas without its receptors.

Adenoma↗
PubMed2002

Nuclear accumulation of basic fibroblast growth factor as a predictor for the recurrence of pituitary adenomas.

Although pituitary adenomas often recur, a reliable predictor for their recurrences has not yet been established. The aim of this study is to assess the utility of the nuclear accumulation of basic fibroblast growth factor (bFGF) as a predictor for the recurrence of pituitary adenomas. We studied 64 patients who had primary pituitary adenomas and underwent operations. The immunohistochemistry for bFGF and MIB-1 was retrospectively examined in paraffin-embedded tissues. The bFGF immunoreactivity in the cytoplasm was assigned one of four grades and the bFGF immunoreactivity in the nucleus was recorded as the bFGF nuclear index (NI), which was calculated as a percentage of tumor cells with the bFGF immunoreactivity in the nuclei in more than 1000 tumor cells. Recurrent adenomas were found in 7 patients during follow-up periods ranging from 8 to 134 months (mean: 57.3). Kaplan-Meier analysis demonstrated that high bFGF NI (>30%) correlated with poor recurrence free rate (p < 0.02). We assessed the relative contribution of bFGF NI to recurrence free by using multivariate (Cox's proportional hazards model) analyses with variable factors. Multivariate analysis showed that only bFGF NI was a potential predictor of recurrence free, independent of all other variables. High bFGF NI (>30%) had a relative risk of 8.9, with a 95% confidence interval of 1.0-74.9 (p < 0.05). We suggest that the bFGF NI may be a potentially useful predictor for the recurrence of pituitary adenomas.

Adenoma↗
PubMed2002

[Postoperative subdural empyema due to Propionibacterium acnes].

Propionibacterium acnes are gram-positive pleomorphic rods that grow under an anaerobic condition. They are the most frequent inhabitants of sebaceous glands of skin, hair follicles, mouth, upper respiratory tract, and as a frequent contaminant in laboratory cultures. Propionibacterium acnes is an underestimated but significant cause of postneurosurgical infection, especially in the presence of foreign bodies such as shunt systems. We present a rare case with a postoperative subdural empyema in which the only pathogen isolated was Propionibacterium acnes. In our case, the clinical course was atypically rapid. The most effective antibiotic therapy for Propionibacterium acnes infections has not been established. However, high dose penicillin in combination with surgical drainage and removal of foreign bodies is recommended as the treatment of choice.

Empyema, Subdural↗
PubMedDate not supplied

Histopathologic findings in human cerebral aneurysms embolized with platinum coils: report of two cases and review of the literature.

This report describes 2-week and 20-month histopathologic findings in small aneurysms embolized with platinum coils. Electron microscopy showed the presence of endothelial cells encroaching on the platinum coils at the orifice of the aneurysm in both cases. We confirm that endothelial growth can be induced as early as 2 weeks after embolization of small human aneurysms with platinum coils, similar to previous observations in animal models and human cases.

Aged↗