103 results on '"N, Saeki"'
Search Results
2. Anex vivostudy of photobiostimulation in the treatment of skin pathologies
- Author
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Antonio Claudio Tedesco, Priscila da Costa Carvalho de Jesus, and Sabrina Ikeda N. Saeki
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0301 basic medicine ,Pathology ,medicine.medical_specialty ,medicine.medical_treatment ,General Physics and Astronomy ,Photodynamic therapy ,Human skin ,In Vitro Techniques ,Pharmacology ,Collagen Type I ,General Biochemistry, Genetics and Molecular Biology ,Photostimulation ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,General Materials Science ,Low-Level Light Therapy ,Low level laser therapy ,Skin ,Wound Healing ,Photosensitizing Agents ,biology ,Chemistry ,General Engineering ,General Chemistry ,Elastin ,030104 developmental biology ,Matrix Metalloproteinase 9 ,Photochemotherapy ,biology.protein ,Matrix Metalloproteinase 2 ,Wound healing ,Type I collagen ,Ex vivo - Abstract
Photodynamic therapy (PDT) and low level laser therapy (LLLT) may mutually improve the outcomes on the healing process of chronic wounds and other skin pathologies, through processes known to stimulate the proliferation of dermal cellular structures, as well as antimicrobial application. This study proposes the use of nanoemulsion containing aluminium phthalocyanine chloride (ClAlPc) as photosensitizer (PS), to establish the most appropriate protocol for photostimulation in human skin biopsies, associated to type I collagen and elastin production. The combined effect of PS and light (diode laser at 670 nm) at three different doses is compared to the effect of light itself at doses of 70, 140 and 700 mJ ċ cm-2 , 7 and 14 days after irradiation. Histological analysis reveals the increase in collagen and elastin, higher than 20%, 14 days after treatment with PS and light at 140 mJ ċ cm-2 . Higher doses of light promote an inhibitory effect, leading to tissue degradation. In addition, the expression levels of the enzymes MMP-2 and MMP-9 (Gelatinases A and B - participant in various processes including tumoral progression and wound healing) are detected by gelatin zymography, reinforcing the efficacy of the combined treatment with PS and light at the intermediate dose.
- Published
- 2016
3. GASDERMIN, suppressed frequently in gastric cancer, is a target of LMO1 in TGF-β-dependent apoptotic signalling
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Kazuhiko Aoyagi, T Tatsuta, K Ogawa, K Aoki, D H Kim, T Shiroishi, Kazuyoshi Yanagihara, Hideo Sasaki, Hiromi Sakamoto, M Tamura, T Usui, H Mizushima, N Saeki, Teruhiko Yoshida, and Misao Ohki
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Cancer Research ,Molecular Sequence Data ,Apoptosis ,Biology ,medicine.disease_cause ,Growth factor receptor ,Stomach Neoplasms ,Transforming Growth Factor beta ,Cell Line, Tumor ,TGF beta signaling pathway ,Genetics ,medicine ,Humans ,Promoter Regions, Genetic ,Molecular Biology ,Transcription factor ,Base Sequence ,LIM Domain Proteins ,Cell cycle ,digestive system diseases ,Neoplasm Proteins ,DNA-Binding Proteins ,Gene Expression Regulation, Neoplastic ,Core Binding Factor Alpha 3 Subunit ,Gastric Mucosa ,Cancer cell ,Cancer research ,Transcription Initiation Site ,Carcinogenesis ,Signal Transduction ,Transcription Factors ,Transforming growth factor - Abstract
Defining apoptosis-regulatory cascades of the epithelium is important for understanding carcinogenesis, since cancer cells are considered to arise as a result of the collapse of the cascades. We previously reported that a novel gene GASDERMIN (GSDM) is expressed in the stomach but suppressed in gastric cancer cell lines. Furthermore, in this study, we demonstrated that GSDM is expressed in the mucus-secreting pit cells of the gastric epithelium and frequently silenced in primary gastric cancers. We found that GSDM has a highly apoptotic activity and its expression is regulated by a transcription factor LIM domain only 1 (LMO1) through a sequence to which Runt-related transcription factor 3 (RUNX3) binds, in a GSDM promoter region. We observed coexpression of GSDM with LMO1, RUNX3 and type II transforming growth factor-beta receptor (TGF-betaRII) in the pit cells, and found that TGF-beta upregulates the LMO1- and GSDM-expression in the gastric epithelial cell line and induces apoptosis, which was confirmed by the finding that the apoptosis induction is inhibited by suppression of each LMO1-, RUNX3- and GSDM expression, respectively. The present data suggest that TGF-beta, LMO1, possibly RUNX3, and GSDM form a regulatory pathway for directing the pit cells to apoptosis.
- Published
- 2007
4. Gamma knife surgery for brain metastases: indications for and limitations of a local treatment protocol
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Junichi Ono, Akira Yamaura, Toru Serizawa, T. Iuchi, Yoshinori Higuchi, Osamu Nagano, and N. Saeki
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Diagnostic Imaging ,Male ,Reoperation ,Urologic Neoplasms ,medicine.medical_specialty ,Lung Neoplasms ,medicine.medical_treatment ,Breast Neoplasms ,Brain damage ,Radiosurgery ,Disease-Free Survival ,Postoperative Complications ,Sex Factors ,Cause of Death ,Medical imaging ,Humans ,Medicine ,Karnofsky Performance Status ,Survival rate ,Aged ,Gastrointestinal Neoplasms ,Retrospective Studies ,Neuroradiology ,Neurologic Examination ,medicine.diagnostic_test ,Brain Neoplasms ,business.industry ,Retrospective cohort study ,Interventional radiology ,Middle Aged ,Prognosis ,Surgery ,Survival Rate ,Neoplasms, Unknown Primary ,Brain Damage, Chronic ,Female ,Neurology (clinical) ,Neurosurgery ,Neoplasm Recurrence, Local ,medicine.symptom ,business - Abstract
The purpose of this retrospective study was to evaluate results of a local treatment protocol using gamma knife surgery (GKS) for brain metastases without upfront whole brain radiation therapy (WBRT).Results for 521 consecutive patients satisfying the following 3 criteria were analysed: 1) a maximum of 3 tumours with a diameter of 25 mm or more; 2) no prior WBRT; 3) no surgically in accessible large (30 mm) tumours. Large tumours were surgically removed and all smaller lesions were treated by GKS without up front WBRT. New lesions, detected with follow-up MRI, were appropriately treated with repeat GKS. Overall survival (OS), neurological survival (NS), qualitative survival (QS) and new lesion-free survival (NLFS) curves were calculated and the prognostic values of covariates were obtained. OS and NS were compared according to tumour number.In total, 1023 separate sessions were required to treat 4562 lesions. The primary organs were lung in 369 patients, gastro-intestinal tract in 70, breast in 33, urinary tract in 24, and others/unknown in 25. The median OS period was 9.0 months. On multivariate analysis, the significant prognostic factors for OS were found to be extracranial disease (risk factor: active), Karnofsky performance status (KPS) score (70) and gender (male). NS and QS at one year were 85.6% and 73.0%, respectively. The only significantly poor prognostic factor for NS was carcinomatous meningitis. NLFS at 6 months was 68.9%. For both OS and NS, the differences between a few (/=3) and many (4-10) brain lesions were not significant (OS: p=0.3128, NS: p=0.5509). Patients with numerous (10) tumours had a significantly poorer prognosis than those with/=10.Our protocol, aggressively applying GKS, provides excellent results in selected patients with/=10 brain lesions and no carcinomatous meningitis.
- Published
- 2005
5. <tex>$hboxCF_4$</tex>Decomposition of Flue Gas From Semiconductor Process Using Inductively Coupled Plasma
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S. Odahara, Toshiaki Yamamoto, Tomoyuki Kuroki, N. Saeki, Masaaki Okubo, and J. Mine
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Flue gas ,Argon ,Analytical chemistry ,chemistry.chemical_element ,Chemical vapor deposition ,Decomposition ,Industrial and Manufacturing Engineering ,Carbonyl fluoride ,chemistry.chemical_compound ,chemistry ,Control and Systems Engineering ,Electrical and Electronic Engineering ,Inductively coupled plasma ,Plasma processing ,Stoichiometry - Abstract
Flue gases from the semiconductor process, SF/sub 6/, NF/sub 3/, perfluorocarbons (PFCs) such as CF/sub 4/ and C/sub 2/F/sub 6/, and hydrofluorocarbons such as CHF/sub 3/ are being regulated internationally because their gases have extremely large global warming potential in comparison to CO/sub 2/, and they have a long lifetime. PFCs are used for wafer etching and cleanup of chemical vapor deposition chambers. CF/sub 4/ is one of the most stable gases among PFCs and its decomposition is extremely difficult. The purpose of this paper is to develop a PFCs removal system which can be used as the same power supply for both plasma processing and a CF/sub 4/ emission cleanup system in semiconductor manufacturing processes. This achieves higher efficiency and is more economical than conventional systems. CF/sub 4/ decomposition was investigated at low pressure (29/spl sim/53 Pa) using the inductively coupled plasma (ICP) reactor. When the total flow rate was below 0.189 normal liters per minute and O/sub 2/ concentration exceeded the 0.9 stoichiometric ratio, the complete CF/sub 4/ decomposition efficiency was achieved at 1.2 kW. The amount of O/sub 2/ should be a 1/spl sim/1.45 stoichiometric ratio of CF/sub 4/ to achieve good CF/sub 4/ decomposition. The argon enhanced the decomposition of CF/sub 4/. On the other hand, the helium was insignificant. CF/sub 4/ decomposition efficiency decreased in the presence of N/sub 2/. For CF/sub 4/ decomposition, the energy efficiency for CF/sub 4/ decomposition was 21.0 g/kWh at optimal condition using the ICP reactor. From the Fourier Transform Infrared Spectrophotometer analysis, CO and carbonyl fluoride (COF/sub 2/) were produced except for CO/sub 2/. COF/sub 2/ is toxic, however, it hydrolyzes into HF and CO/sub 2/, so it is easy to eliminate COF/sub 2/ using the scrubber which was located downstream of the dry vacuum pump.
- Published
- 2005
6. <tex>$hboxCF _4$</tex>Decomposition Using Inductively Coupled Plasma: Effect of Power Frequency
- Author
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Toshiaki Yamamoto, J. Mine, Tomoyuki Kuroki, N. Saeki, and Masaaki Okubo
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Power frequency ,Chemistry ,Analytical chemistry ,Infrared spectroscopy ,Decomposition ,Industrial and Manufacturing Engineering ,Power (physics) ,Volumetric flow rate ,symbols.namesake ,Fourier transform ,Control and Systems Engineering ,symbols ,Electrical and Electronic Engineering ,Inductively coupled plasma - Abstract
The performance evaluation of CF/sub 4/ decomposition efficiency using 2- and 4-MHz power supplies was carried out as a function of the power, the pressure, the flow rate, and the quantity of O/sub 2/ addition. When the 2- and 4-MHz power supplies were used, almost complete CF/sub 4/ removal was achieved at 2.0 and 3.0 kW, respectively, when the CF/sub 4/ flow rate was 0.20 normal liters per minute. The optimum O/sub 2//CF/sub 4/ ratio should be in the range of 1.0/spl sim/1.25 in order to decompose CF/sub 4/ efficiently. The CF/sub 4/ decomposition efficiency using the 2-MHz power supply was significantly higher than that of the 4-MHz power supply under the same power, pressure, and flow rate. Significant amounts of byproducts such as COF/sub 2/ and CO were identified by the Fourier transform infrared spectrophotometer analysis in addition to CO/sub 2/.
- Published
- 2005
7. Use of blue-on-yellow perimetry for detection of sectoranopia
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Naoya Fujimoto, M Kubota, N Saeki, and Emiko Adachi-Usami
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Ophthalmology ,medicine.medical_specialty ,business.industry ,Medicine ,business - Published
- 2004
8. Abstract PR620
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K. Yanabe, R. Nakamura, N. Saeki, S. Elbegzaya, A. Kutluk, H. Hirano, M. Yoshizumi, T. Tsuji, and M. Kawamoto
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Mechanical property ,Anesthesiology and Pain Medicine ,medicine.diagnostic_test ,business.industry ,Anesthesia ,Laryngoscopy ,Remifentanil ,medicine ,Stimulus (physiology) ,business ,medicine.drug - Published
- 2016
9. Abstract PR618
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E. Sukhdorj, R. Nakamura, N. Saeki, K. Yanabe, A. Kutluk, H. Hirano, M. Yoshizumi, T. Tsuji, and M. Kawamoto
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Laparoscopic surgery ,medicine.medical_specialty ,Anesthesiology and Pain Medicine ,business.industry ,Anesthesia ,medicine.medical_treatment ,Plasma concentration ,Mechanical impedance ,Remifentanil ,Medicine ,business ,Surgery ,medicine.drug - Published
- 2016
10. MRI of ectopic posterior pituitary bright spot with large adenomas: appearances and relationship to transient postoperative diabetes insipidus
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Motoo Kubota, Hisayuki Murai, N. Wagai, K. Sunami, Ichiro Tatsuno, Yasushi Saito, H. Tokunaga, N. Saeki, and Akira Yamaura
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Adenoma ,Male ,Pituitary gland ,medicine.medical_specialty ,Postoperative Complications ,Pituitary Gland, Posterior ,Pituitary adenoma ,Posterior pituitary ,medicine ,Humans ,Pituitary Neoplasms ,Radiology, Nuclear Medicine and imaging ,Pituitary stalk ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Ectopic Posterior Pituitary ,Surgery ,medicine.anatomical_structure ,Diabetes insipidus ,Female ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,Nuclear medicine ,business ,Diabetes Insipidus - Abstract
MRI of large pituitary adenomas has revealed that a posterior pituitary bright spot (PPBS), comprising ADH-containing neurosecretory granules, is commonly ectopic before surgery and attached to the tip of the pituitary stalk late after surgery. Although the PPBS indicates functional integrity of the posterior lobe, transient diabetes insipidus (DI), caused by deficiency of ADH, is frequent early after surgery. We attempted to clarify how the shape, signal intensity and site of the PPBS before surgery are related to transient DI in the early postoperative period. We carried out MRI on 15 patients with a large adenoma and an ectopic PPBS before surgery and then within 1 week (early), 1-2 months (intermediate) and 6 or more months (late) after the operation. There were nine who had transient DI, which subsided by the intermediate study; none had permanent DI. Regardless of transient DI, the PPBS was visible, and its signal intensity was similar, on all postoperative studies. Although 11 did not change in shape, four showed a remarkable change from a flat shape before surgery to a rounded one postoperatively. On the intermediate MRI, the PPBS had descended to the level of the diaphragma as mass effect disappeared.
- Published
- 2003
11. Potential role of the anterior spinal artery in preventing propagation of thrombus in a therapeutically occluded vertebral artery: angiographic studies before and after endovascular treatment
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Akira Yamaura, K. Kado, S. Kobayashi, S. Hirai, Yoshio Uchino, N. Saeki, Eiichi Kobayashi, and Iwao Yamakami
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Adult ,Male ,medicine.medical_specialty ,Therapeutic Occlusion ,Vertebral artery ,Anterior spinal artery ,Arteriovenous fistula ,Radiography, Interventional ,Risk Factors ,medicine.artery ,Occlusion ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Thrombus ,Vertebral Artery ,Retrospective Studies ,Central Nervous System Vascular Malformations ,Lateral medullary syndrome ,business.industry ,Intracranial Aneurysm ,Middle Aged ,medicine.disease ,Embolization, Therapeutic ,Cerebral Angiography ,Surgery ,Posterior inferior cerebellar artery ,Spinal Cord ,Neurology (clinical) ,Radiology ,Cardiology and Cardiovascular Medicine ,business - Abstract
Therapeutic occlusion of the vertebral artery (VA) is one of the treatments for unclippable aneurysms and other lesions, although controversy still surrounds the appropriate site for occlusion to attain selective thrombosis of the lesion while avoiding ischaemic complications. The lower two-thirds of the lateral medulla are supplied by perforating branches of both the VA and the posterior inferior cerebellar artery (PICA). However, in patients without a PICA or in whom the origin of the PICA is low (at or below the foramen magnum), the VA is usually the only source of perforating vessels. We retrospectively studied the results of VA occlusion on such anatomically high-risk patients, and propose a safer procedure. Five high-risk patients underwent therapeutic occlusion of the VA for dissecting aneurysms or arteriovenous fistula. A lateral medullary syndrome developed due to propagation of thrombus after the procedure in two patients in whom angiography did not demonstrate the anterior spinal artery (ASA) within the stump of the VA. Ischaemic signs did not develop in the other three patients, in whom the ASA was visible, and retrograde flow was observed proximal to the origin of the ASA. This suggests that the ASA may play a role in preventing propagation of thrombus in the VA distal to the site of occlusion and supply blood to its perforating arteries in high-risk patients. Angiographic assessment of the ASA may be useful for predicting the likelihood of the lateral medullary syndrome developing with therapeutic occlusion of the VA in patients without a PICA or with one whose origin is low.
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- 2002
12. Heavily T2 Weighted MR Images of Anterior Optic Pathways in Patients with Sellar and Parasellar Tumours - Prediction of Surgical Anatomy
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T. Iuchi, Motoo Kubota, Akira Yamaura, Hisayuki Murai, N. Saeki, Kenro Sunami, and N. Fujimoto
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Adenoma ,Adult ,Male ,Optic chiasm ,Anterior commissure ,Patient Care Planning ,Meningioma ,Craniopharyngioma ,Predictive Value of Tests ,Pituitary adenoma ,medicine.artery ,Preoperative Care ,Meningeal Neoplasms ,medicine ,Humans ,Pituitary Neoplasms ,Aged ,business.industry ,Optic Nerve ,Anatomy ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Anterior communicating artery ,medicine.anatomical_structure ,Optic Chiasm ,Optic chiasma ,Optic nerve ,Female ,Surgery ,Neurology (clinical) ,Nuclear medicine ,business ,Craniotomy ,Forecasting - Abstract
Objective. Location of anterior optic pathways in sellar and parasellar tumours was preoperatively evaluated, by use of heavily T2 weighted MR images. Methods. Heavily T2 and conventional T1 weighted images were studied in 20 patients with sellar and parasellar tumours who underwent craniotomy. Pathology revealed pituitary adenoma in 5 patients, craniopharyngioma in 8 and parasellar meningioma in 7. Maximum sizes ranged from 15 mm to 58 mm. Sequence parameters of TR/TE for heavily T2 weighted and T1 weighted images were 5800/220 msec and 600/20 msec, respectively, and slice thickness was 3 mm for both. Results. The anterior optic pathway was detected in 95% on heavily T2 weighted images and 50% on T1 weighted images. All preoperative heavily T2 weighted images were compatible with operative findings. The optic chiasms were most commonly supero-posterior in pituitary adenomas, anterior (prefixed) in craniopharyngiomas and posterior in meningiomas. The optic nerves were commonly located superior or lateral to the tumours. However, parasellar meningiomas, off the midline, revealed the optic nerves in various locations, depending on the tumour origin. In such tumours, heavily T2 weighted images provided surgical information on the width of the working space through prechiasmal and/or optico-carotid spaces in the pterional approach. Spatial relation of the tumours to the lamina terminalis, anterior commissure and anterior communicating artery complex was clearly shown in craniopharyngioma patients, who underwent the anterior interhemispheric approach. Conclusion. Heavily T2 weighted MR images are useful in determining the location of optic pathways and surgical approach and in individual prediction of the anatomy for even large sellar and parasellar tumours.
- Published
- 2002
13. Treatment of Asymptomatic Unruptured Intracranial Aneurysms
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Motoo Kubota, Akira Yamaura, M. Odaki, K. Sunami, Kouichi Isobe, Toru Serizawa, Shinji Hirai, J. Ono, N. Saeki, and M. Sato
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medicine.medical_specialty ,business.industry ,Original Articles ,Rupture rate ,Asymptomatic ,030218 nuclear medicine & medical imaging ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,Postoperative results ,medicine ,In patient ,medicine.symptom ,Endovascular treatment ,Complication ,Clinical decision ,business ,030217 neurology & neurosurgery ,Decision analysis - Abstract
The indication of preventive surgery for patients who harbor asymptomatic unruptured intracranial aneurysms remains controversial. To evaluate the benefit of this treatment, we investigated the management outcome in 128 patients with 157 unruptured aneurysms. Surgery was planned in patients 70 years old or younger without serious systemic complications. A total of 77 patients underwent surgery including four endovascular interventions, and conservative management was chosen in 51 patients. There was no mortality and 6.5% morbidity as postoperative results, and no complication was found after endovascular treatment. Among the patients in conservative management, four patients suffered from subsequent rupture during the total follow-up period of 148 person-years. The annual rupture rate was estimated at 2.7%. According to the clinical decision analysis based on our data, preventive surgery is beneficial for a Japanese 70 years old or younger. However, the expected utility decreases if the rupture rate is set at 0.5% or 0.05%, posing a doubt about the benefit of the surgery. Decision analysis provides an aid for logical and objective choice in the management of unruptured aneurysms. The actual risk of rupture has a major impact on decision making in therapeutic strategy.
- Published
- 2001
14. Recurrent Neurohypophyseal Germinoma Causing Invasion Localized to Temporal Bone Marrow-Unreported Neuroimaging Studies Compared to Autopsy Findings
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H. Kitou, Osamu Nagano, Motoo Kubota, Akira Yamaura, Ichiro Tatsuno, T. Sakaida, Hisayuki Murai, K. Harigaya, and N. Saeki
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Adult ,medicine.medical_specialty ,Pathology ,Neurology ,Autopsy ,Skull Base Neoplasms ,Neuroimaging ,Temporal bone ,medicine ,Humans ,Pituitary Neoplasms ,Neuroradiology ,Germinoma ,business.industry ,Temporal Bone ,medicine.disease ,Radiography ,Female ,Surgery ,Neurology (clinical) ,Neurosurgery ,Neoplasm Recurrence, Local ,Bone Marrow Neoplasms ,business ,Complication - Published
- 2001
15. Lymphocytic infundibulo-neurohypophysitis associated with recurrent optic neuritis
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A Tamiya, A Mizota, and N. Saeki
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Adult ,medicine.medical_specialty ,Optic Neuritis ,genetic structures ,Hypophysitis ,Pituitary Diseases ,Prednisolone ,Autoimmune Diseases ,Pituitary Gland, Posterior ,Recurrence ,Posterior pituitary ,Ophthalmology ,medicine ,Humans ,Cranial nerve disease ,Optic neuritis ,Glucocorticoids ,Abducens nerve ,Pituitary stalk ,Right optic nerve ,business.industry ,General Medicine ,medicine.disease ,Magnetic Resonance Imaging ,Surgery ,medicine.anatomical_structure ,Optic nerve ,Female ,Neurology (clinical) ,medicine.symptom ,business ,Diabetes Insipidus - Abstract
A 38-year-old woman presented with diabetes insipidus. The T1-weighted images showed a loss of the hyperintense signal of the posterior pituitary and thickening of the pituitary stalk. DDAVP was started with the diagnosis of lymphocytic infundibulo-neurohypophysitis (LINH). Three months later, she complained of right visual acuity loss. MRI revealed right optic nerve swelling, compatible with the diagnosis of the retrobulbar optic neuritis. She had two other such episodes in the next 3 months. She developed a transient oculomotor and abducens nerve palsies as well. Each time the symptoms disappeared with corticosteroid therapy. The pituitary stalk became normal in size 6 months later. LINH and recurrent optic neuritis occurred in a short duration. Accordingly, a common causative background is suspected. Since the auto-immune process has been hypothesized as a cause of optic neuritis, our case may present further clinical evidence to support the hypothesis of an auto-immune mechanism for LINH.
- Published
- 2001
16. Oedema along the optic tracts due to pituitary metastasis
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Motoo Kubota, N. Fujimoto, Hisayuki Murai, and N. Saeki
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Male ,Pituitary gland ,Pathology ,medicine.medical_specialty ,Optic tract ,Adenocarcinoma ,Metastasis ,Cerebral edema ,Central nervous system disease ,Edema ,Humans ,Medicine ,Pituitary Neoplasms ,Visual Pathways ,Clinical significance ,business.industry ,General Medicine ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Craniopharyngioma ,medicine.anatomical_structure ,Diabetes insipidus ,Female ,Surgery ,Neurology (clinical) ,business - Abstract
The MRI finding of oedema along the optic tract has been reported in patients with craniopharyngioma, as a useful diagnostic sign among common pituitary tumours. We report two patients with pituitary metastasis with this MRI finding. A 59-year-old woman and a 54-year-old man had diabetes insipidus and extraocular impairment due to a pituitary metastasis from adenocarcinoma of lung and colon, respectively. Several months later, they noticed rapidly deteriorating visual field and acuity impairment. MRI revealed enlarged pituitary mass accompanied by marked oedema along the bilateral optic tracts. To our knowledge, this is the first MRI report of oedema along the optic pathway due to pituitary metastasis. Our cases and review of literature indicate that this MRI sign is non-specific. Appearance of the oedema well corresponded to the initiation of visual complaint, which make a good contrast to reported clinical presentations of craniopharyngioma. Clinical significance and pathomechanism of this MRI sign are ...
- Published
- 2001
17. MRI Findings and Clinical Manifestations in Rathke's Cleft Cyst
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Akira Yamaura, Kenro Sunami, N. Saeki, and Y Sugaya
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Adult ,Male ,medicine.medical_specialty ,Pathology ,Vision Disorders ,Central nervous system disease ,Pituitary adenoma ,medicine ,Humans ,Cyst ,Central Nervous System Cysts ,Aged ,Cerebral Hemorrhage ,Retrospective Studies ,Neuroradiology ,medicine.diagnostic_test ,Rathke's cleft cyst ,Brain Neoplasms ,business.industry ,Incidentaloma ,Magnetic resonance imaging ,Middle Aged ,Prognosis ,medicine.disease ,Magnetic Resonance Imaging ,Disease Progression ,Female ,Surgery ,Neurology (clinical) ,Neurosurgery ,Radiology ,business - Abstract
We retrospectively analysed patients with histologically proven Rathke's cleft cyst (RCC) in relation to the clinical manifestations and MRI findings, in particular, of cyst size and intensity in order to obtain an insight into their growing mechanisms, clinical presentations and their management. Eleven patients with RCC were divided into two groups based on T1 weighted images(WI). The A group consisted of 4 patients with cyst of low intensity in T1 WI. The age averaged 64.5 years. Their initial complaints were visual field defects(VFD). Their complaints were rather insidious. The maximum cyst size averaged 27.8+/-2.4 mm. The B group consisted of 7 patients with cyst of iso- or high-intensity in T1 WI. Two patients in the B group showed mixture of low and high and iso- and high-intensity, suggesting the presence of bleeding at the onset of symptoms or growing mechanism of the cysts. In the B group the age averaged 39.9 years, being lower than that in the A group. (P=0.0140 with Mann-Whitney's U test) The 5 patients out of 7 showed headache of insidious type or acute onset and the 3 showed a fluctuation of the VFD. The average size was 21.7+/-3.5 mm and smaller than that of the A group. (P=0.0298 with Mann-Whitney's U test) Our study has shown that the cyst with iso-to high intensity on T1 WI may cause clinical symptoms with a smaller size than cysts of the low intensity. In the former cyst pattern the onset and growing mechanism may be related to bleeding. The patients with this pattern are more likely to have acute and/or fluctuation of clinical presentations. Knowing these various clinical manifestations based on MRI pattern will be of help in following and managing patients with RCC.
- Published
- 1999
18. Spontaneous Disappearance of Temporo-Frontal Arachnoid Cyst in a Child
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N. Saeki, Toshihiro Yamauchi, and Akira Yamaura
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Male ,medicine.medical_specialty ,Remission, Spontaneous ,Spontaneous remission ,Middle cranial fossa ,Asymptomatic ,Arachnoid cyst ,parasitic diseases ,Temporal bone ,medicine ,Humans ,Cyst ,business.industry ,Head injury ,Infant ,medicine.disease ,Temporal Lobe ,Frontal Lobe ,nervous system diseases ,Surgery ,Arachnoid Cysts ,medicine.anatomical_structure ,Disease Progression ,Neurology (clinical) ,Neurosurgery ,medicine.symptom ,Tomography, X-Ray Computed ,business ,Follow-Up Studies - Abstract
We report a child with a large temporo-frontal arachnoid cyst which resolved spontaneously. There was no history of a head injury. The patient was a boy aged 1.6 years. Though a large head was pointed out (+2SD), no therapeutic intervention was made because the relationship of the head circumference and the cyst was not established. No change in cyst size was visualized on the follow-up CTs at the age of 2.5 years and 6 years. At the age of 7 years, the arachnoid cyst had completely disappeared on CT. In order not to overlook a minute change in cyst size, the volumetry of the cyst and the intracranial cavity was performed, using the Photoshop, Macintosh. Both the cyst volume and the volume ratio of the cyst to the intracranial cavity slightly decreased and then increased. It is speculated that the cyst spontaneously ruptured by factors such as extreme breath holding and crying on the presence of the higher intracystic tension which might become a factor to accelerate spontaneous rupture of the cyst. Since a number of paediatric cases of symptomatic arachnoid cysts in need of surgical intervention has been larger than that of adult cases, we can speculate that a large arachnoid cyst might spontaneously resolve more frequently than we had expected. This case demonstrates that the surgical treatment of asymptomatic arachnoid cyst in the middle cranial fossa is not necessarily indicated in children.
- Published
- 1999
19. Bone window CT evaluation of the nasal cavity for the transsphenoidal approach
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N. Saeki, Numata T, Hoshi S, and Akira Yamaura
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Adenoma ,Male ,Nasal cavity ,medicine.medical_specialty ,Adolescent ,medicine.medical_treatment ,Mucous membrane of nose ,Transsphenoidal approach ,Inferior nasal concha ,Pituitary adenoma ,Preoperative Care ,otorhinolaryngologic diseases ,Humans ,Medicine ,medicine.bone ,Pituitary Neoplasms ,Nose ,Aged ,Transsphenoidal surgery ,business.industry ,General Medicine ,Middle Aged ,medicine.disease ,Surgery ,medicine.anatomical_structure ,Acromegaly ,Female ,Neurology (clinical) ,Middle nasal concha ,Nasal Cavity ,Tomography, X-Ray Computed ,business ,Nuclear medicine - Abstract
Bone window CT findings sliced parallel to the transsphenoidal surgical route were evaluated preoperatively in 104 patients with pituitary lesions in order to assess their clinical significance. (1) The width and depth of the transsphenoidal operative fields were measured. The piriform aperture was 26.3 mm (SD 2.5) in maximum width, the origin of inferior nasal concha 27.0 mm (SD 2.5) and the origin of the middle nasal concha 26.8 mm (SD 3.8), respectively. The distance between the piriform aperture and the sellar floor was 61.6 mm (SD 3.6). The operative field was cylindrical in shape, approximating 26-27 mm in width and 62 mm in depth. (2) The width and length of bony nasal cavity were different by 2-3 mm in patients with and without acromegaly. (3) In re-operated patients, the location of thinned or atrophic nasal mucosa, residual bony septum and narrow sellar floor opening, which needed further bony removal were demonstrated. Bone window CT provides direct visualization of the nasal anatomy for the approach, and is useful in screening for patients with a narrow nasal cavity. It helps to determine rhinological manoeuvres for providing wide operative fields at the nasal cavity and sellar floor.
- Published
- 1999
20. MRI Prediction of Fibrous Pituitary Adenomas
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Kenro Sunami, Akira Yamaura, M. Tanaka, T. Iuchi, and N. Saeki
- Subjects
Adenoma ,Adult ,Male ,Pathology ,medicine.medical_specialty ,medicine.medical_treatment ,Transsphenoidal approach ,Hardness ,Consistency (statistics) ,Pituitary adenoma ,Humans ,Medicine ,Pituitary Neoplasms ,Retrospective Studies ,Neuroradiology ,Transsphenoidal surgery ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Weak correlation ,Female ,Surgery ,Collagen ,Neurology (clinical) ,business ,Nuclear medicine ,Forecasting - Abstract
The transsphenoidal approach is a less invasive and safer procedure for removing pituitary adenomas. However, this procedure becomes extremely difficult when the tumour consistency is fibrous as encountered in about 10% of pituitary adenomas. In this study, we investigated predicting factors of tumour consistency in magnetic resonance images (MRIs). MRIs of two groups, twenty-one soft and five firm (fibrous) adenomas, were retrospectively evaluated and compared in respect of tumour consistency. To compare the two groups objectively, tumour densities on MRI films and percentage of collagen content on operative specimens were expressed as numerical data using NIH-image. The relationships between collagen content and T1-weighted images, T2-weighted images, grade of enhancement effect, and heterogeneity of enhancement were investigated. Signal intensities on T1-weighted images were not correlated with tumour consistency, whereas those on T2-weighted images were significantly correlated with the percentage of collagen content. Adenomas, showing lower signal intensities on T2-weighted images, contained more collagen. On enhanced images, homogeneously enhanced adenomas tended to include more collagen, even though the grade of enhancement effect showed only weak correlation with the tumour hardness. MRIs give us useful information on tumour consistency. Adenomas may be firm and fibrous if they show low signal intensities on T2-weighted images and homogeneous enhancement. To remove such tumours, a long sized and small-calibred ultrasonic aspirators applicable to transsphenoidal approach must be prepared and multistaged operations may be more than likely needed.
- Published
- 1998
21. Concrete Strength of Surface Layer
- Author
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T. Horiguchi, N. Saeki, and T. Sugawara
- Subjects
Materials science ,General Materials Science ,Surface layer ,Composite material - Published
- 1995
22. Rathke’s cleft cyst with large frontal extension: unusual shape and pathomechanism of its formation
- Author
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Akira Yamaura, Kenro Sunami, Souichi Sunada, Hoshi S, and N. Saeki
- Subjects
medicine.medical_treatment ,urologic and male genital diseases ,Central nervous system disease ,Arachnoid cyst ,Physiology (medical) ,medicine ,Humans ,Cyst ,Central Nervous System Cysts ,Pathological ,Transsphenoidal surgery ,Rathke's cleft cyst ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,General Medicine ,Anatomy ,Middle Aged ,medicine.disease ,female genital diseases and pregnancy complications ,Craniopharyngioma ,Neurology ,Female ,Surgery ,Neurology (clinical) ,business - Abstract
The patient was a 62 year old woman who presented with a visual field defect. Magnetic resonance images showed an intra-and supra-sellar low intensity mass on T1 weighted images. The preoperative diagnosis was craniopharyngioma, Rathke's cleft cyst (RCC) or arachnoid cyst. The patient underwent transsphenoidal surgery & the pathological diagnosis was RCC. We conclude that although RCC has a round, ovoid or dumb-bell shaped configuration, it may present a unusual shape in cases with preconditions, as were seen in our patient.
- Published
- 2000
23. Inter-Reflection Compensation for Immersive Projection Display
- Author
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Takashi Matsuyama, Hitoshi Habe, and N. Saeki
- Subjects
Photometry (optics) ,Photometric calibration ,business.industry ,Computer science ,Computer graphics (images) ,Projection display ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Computer vision ,Specular reflection ,Artificial intelligence ,Inverse problem ,business ,ComputingMethodologies_COMPUTERGRAPHICS - Abstract
This paper proposes an effective method for compensating inter-reflection in immersive projection displays (IPDs). Because IPDs project images onto a screen, which surrounds a viewer, we have perform out both geometric and photometric corrections. Our method compensates inter-reflection on the screen. It requires no special device, and approximates both diffuse and specular reflections on the screen using block-based photometric calibration.
- Published
- 2007
24. DURABILITY OF HARDENED MORTAR UNDER HIGH-VACUUM CONDITION
- Author
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N Saeki, T Horiguchi, and Yuki Sakoi
- Subjects
Materials science ,Ultra-high vacuum ,Composite material ,Mortar ,Durability - Published
- 2005
25. ASSESSMENT OF CHLORIDE PENETRATION INTO FIBRE REINFORCED CONCRETE UNDER LOADING
- Author
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null Antoni, T Horiguchi, and N Saeki
- Published
- 2005
26. BILATERAL SAME DAY SURGERY FOR BILATERAL PERFORATED CHRONIC OTITIS MEDIA (SECOND REPORT)
- Author
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K. Tsuji, Mieko Sone, M. Sakagami, H. Katsura, N. Saeki, and Y. Mishiro
- Subjects
medicine.medical_specialty ,business.industry ,Chronic otitis ,medicine ,business ,Surgery - Published
- 2004
27. Unusually widened perivascular spaces in the cerebral hemisphere: the importance of MRI for diagnosis of a benign clinical entity
- Author
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Akira Yamaura, Motoo Kubota, N. Saeki, and Hisayuki Murai
- Subjects
medicine.medical_specialty ,Pathology ,Diagnostico diferencial ,Brain Edema ,Central nervous system disease ,Diagnosis, Differential ,Glioma ,Medicine ,Humans ,Perivascular space ,Central Nervous System Cysts ,business.industry ,Brain Neoplasms ,General Medicine ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Cerebral hemisphere ,Surgery ,Female ,Neurology (clinical) ,Neurosurgery ,business ,Tomography, X-Ray Computed ,Follow-Up Studies - Abstract
(2003). Unusually widened perivascular spaces in the cerebral hemisphere: the importance of MRI for diagnosis of a benign clinical entity. British Journal of Neurosurgery: Vol. 17, No. 6, pp. 576-577.
- Published
- 2004
28. Compressive Strength and Leachate Characteristics of New Green CLSM with Eco-Cement and Melted Slag from Municipal Solid Waste
- Author
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N. Saeki and I Horiguchi
- Subjects
Cement ,Compressive strength ,Municipal solid waste ,Materials science ,Waste management ,Fly ash ,visual_art ,visual_art.visual_art_medium ,Slag ,Leachate - Published
- 2004
29. CF/sub 4/ decomposition of flue gas from semiconductor process using inductively coupled plasma
- Author
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T. Kuroki, J. Mine, S. Odahara, M. Okubo, T. Yamamoto, and N. Saeki
- Published
- 2003
30. Model experiment of a launcher of a Deep-Sea Monitoring Robot System
- Author
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K. Tamura, K. Hisamatsu, Tadashi Nimura, N. Saeki, H. Ando, Y. Wada, Michio Ueno, and K. Maeda
- Subjects
Optical fiber cable ,Engineering ,business.industry ,Rudder ,Remotely operated underwater vehicle ,law.invention ,Shipbuilding ,Fuselage ,law ,Umbilical cable ,Underwater ,business ,Underwater acoustics ,Marine engineering - Abstract
National Maritime Research Institute (NMRI), in cooperation with Underwater Technology Research Center, Institute of Industrial Science, University of Tokyo, is developing a Compact Deep-Sea Monitoring Robot System for investigation of sunken ships in deep sea. This system is consisted of a launcher and a small vehicle, and it has characteristics of both AUV and ROV. A launcher corresponds with its mother ship by using optical fiber cable. There is no umbilical cable between a launcher and a vehicle, and the communication is performed by acoustic communication. A launcher submerges holding a vehicle by gravity. It controls its rudders for approaching to a target point. Just before reach the sea bottom, a launcher releases an anchor, launches a vehicle to start mission. In order to pursue the best configuration for effective horizontal movement during descending motion, preliminary calculation and experiments were carried out for two types of configurations, a fuselage with fins and rudders and a fuselage with rudders but no fins. This paper describes the results of calculation and experiments at a deep-sea model basin. The basic mechanism of descend were confirmed.
- Published
- 2003
31. Demonstration of the optic pathway in large pituitary adenoma on heavily T2 weighted MR images
- Author
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M Eda, K Sunami, N. Fujimoto, and N. Saeki
- Subjects
Adenoma ,Adult ,Male ,genetic structures ,Vision Disorders ,Optic chiasm ,Anterior commissure ,Pituitary neoplasm ,Pituitary adenoma ,medicine.artery ,medicine ,Humans ,Pituitary Neoplasms ,Visual Pathways ,Aged ,Third ventricle ,business.industry ,Optic Nerve ,General Medicine ,Anatomy ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Anterior communicating artery ,medicine.anatomical_structure ,Optic Chiasm ,Optic nerve ,Surgery ,Female ,Neurology (clinical) ,Visual Fields ,business - Abstract
The objective of the investigation was to understand preoperatively the detailed anatomical relationship of large pituitary adenomas to surrounding structures, using the heavily T2-weighted reversed (T2R) MR images. This study consisted of 28 patients with pituitary adenoma, presenting with visual disturbance. The MRI scanner used was a Gyroscan ACSNT 1.5T and the slice thickness of the image was 3 mm with 0.5 mm interslice gap. The relation of pituitary adenoma to optic pathway and to the degree of visual field defect was assessed. Relations of the optic chiasm to adenoma were classified into three types: anterior, superior and posterior. The optic chiasm was directly visualized and identifiable in all patients studied. It was located anterior in four cases, superior in 22 and posterior in two in relation to the adenoma. Its location was further confirmed by the anatomical delineation of surrounding structures such as anterior commissure and lamina terminalis. Optic nerve or tract was unidentifiable in one case, for each category. Detectability of each optic component was higher on T2R images than on conventional T1-weighted images. The adenoma extended into and in front of the third ventricle in anterior and posterior types, respectively. The anterior communicating artery complex and the optic pathway were relocated together in anterior and superior types, and were separated in the posterior type. In a case of the posterior type, the complex was sectioned to obtain a wider surgical field during anterior interhemispheric approach. While degrees of visual field defect were proportional to tumour size in the superior type, they were unrelated in the anterior and posterior types. On choosing a transcranial approach, the transcallosal route is unsuitable for an adenoma of posterior type, which extends in front of the third ventricle. This preoperative MRI information makes it possible to visualize directly the optic pathway even in huge adenomas, and is useful in predicting surgical anatomy and selecting a proper surgical approach.
- Published
- 2002
32. Effect of Fiber Reinforcement on Residual Properties of High-Strength Concrete Under EIevated Temerature
- Author
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T Horiguchi, T Takano, N Saeki, and T D Lin
- Subjects
Polypropylene ,Cement ,Water–cement ratio ,Structural material ,Materials science ,Fiber-reinforced concrete ,Thermal diffusivity ,Spall ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,Composite material ,Water content - Abstract
This paper examines the effect of fiber reinforcement on mitigation of explosive spalling and residual properties of high strength concrete under elevated temperatures (600 deg C). The experimental work was conducted on the influence of 3 parameters associated with fire resistance. These 3 parameters are an addition of polypropylene fibers and/or polymer beads, the moisture content of the concrete, and the water to cement ratio. Results show that the internal temperature elevation was mitigated in the test specimens that contained the fibers or beads, that were melted by heating, by low cement-water ratio, and by high moisture content. The accompanying strains due to heating at these conditions were reduced in the test specimens.
- Published
- 2002
33. Magnetic-Field-Assisted Gliding Arc Discharge Plasma for Surface Modification
- Author
-
N. Saeki, Tomoyuki Kuroki, Mitsuru Tahara, Zongbao Feng, and Masaaki Okubo
- Subjects
Quantitative Biology::Biomolecules ,Nuclear and High Energy Physics ,Materials science ,Plasma ,Mechanics ,Condensed Matter Physics ,Plasma generator ,Quantitative Biology::Cell Behavior ,Magnetic field ,Quantitative Biology::Subcellular Processes ,Arc (geometry) ,Electric arc ,Condensed Matter::Materials Science ,Plasma arc welding ,Physics::Plasma Physics ,Plasma torch ,Surface modification - Abstract
This paper presents a novel design for a gliding arc plasma generator assisted by a magnetic field for surface modification. The introduction of the magnetic field enhances the motion and reach of the gliding arc discharge. As a result, a 19-cm-long gliding arc discharge plasma was successfully generated and was found to be effective for surface modification.
- Published
- 2011
34. Abdominal aortic injury during vertebroplasty: a case report
- Author
-
C. Matsumoto, N. Saeki, M. Nakao, and A. Umeda
- Subjects
medicine.medical_specialty ,Anesthesiology and Pain Medicine ,business.industry ,Aortic injury ,medicine ,business ,Surgery - Published
- 2014
35. Long-term Karnofsky performance status and neurological outcome in patients with neurohypophyseal germinomas
- Author
-
Motoo Kubota, Akira Yamaura, Hisayuki Murai, N. Saeki, and N. Fujimoto
- Subjects
Adult ,Male ,medicine.medical_specialty ,Adolescent ,medicine.medical_treatment ,Vision Disorders ,Lesion ,Central nervous system disease ,Pituitary Gland, Posterior ,Diabetes mellitus ,medicine ,Humans ,Pituitary Neoplasms ,Stage (cooking) ,Karnofsky Performance Status ,Child ,Retrospective Studies ,Chemotherapy ,Germinoma ,Radiotherapy ,business.industry ,General Medicine ,medicine.disease ,Surgery ,Radiation therapy ,Hemiparesis ,Treatment Outcome ,Female ,Neurology (clinical) ,medicine.symptom ,Visual Fields ,business - Abstract
Long-term posttreatment Karnofsky Performance Status (KPS) and neurological status of 16 patients with neurohypophyseal (NH) germinomas were retrospectively analysed, in order to deduce the best treatment modality to achieve a good outcome. The average age at treatment was 15.5 years (rouge 6-26) and they were followed up for 107.3 months (26-209). The KPS averaged 81.5 (0-100). Three patients were below 60 in the KPS. The first one had hemiparesis due to a delayed cerebrovascular accident (CVA), and the second became indifferent and inactive with recent memory loss. The third died from marginal recurrence of tumour and subsequent systemic metastasis. The low scores were all more or less attributable to complications related to irradiation: delayed CVA, diffuse cortical atrophy and inappropriate selection of irradiation field, respectively. The second case had the tumour origin at the hypothalamus, which indicates intraparenchymal tumour location as another factor to worsen the quality of life (QOL). Visual field and acuity, and EOM impairment were observed in eight and five patients, respectively. It improved in all patients but one. The visual and EOM dysfunction recovered satisfactorily and was not a disabling factor. The intraparenchymal lesion resulting in hemiparesis and higher cortical dysfunction due to either irradiation-related complications or tumour invasion is a major determining factor of lower KPS. Irradiation related complications are considered to be avoidable by reducing radiation dosage with appropriate chemotherapy and/or proper selection of irradiation field. Patients with smaller tumour size of less than 20 mm had higher KPS. Accordingly, repeated studies of tumour markers and neuroimages are required in patients with idiopathic diabetes insipidis, in order to detect the tumour, if present, at the small-sized and early stage.
- Published
- 2001
36. Computed tomography and magnetic resonance imaging of mild head injury--is it appropriate to classify patients with Glasgow Coma Scale score of 13 to 15 as 'mild injury'?
- Author
-
M. Tanaka, Y. Okimura, Akira Yamaura, Yoshio Uchino, and N. Saeki
- Subjects
Adult ,Male ,medicine.medical_specialty ,Adolescent ,Brain damage ,Central nervous system disease ,medicine ,Craniocerebral Trauma ,Humans ,Glasgow Coma Scale ,Prospective Studies ,Neuroradiology ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Head injury ,Interventional radiology ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Prognosis ,Magnetic Resonance Imaging ,Surgery ,Female ,Neurology (clinical) ,Neurosurgery ,Amnesia ,medicine.symptom ,business ,Nuclear medicine ,Tomography, X-Ray Computed - Abstract
The purpose of this study is to examine the relation between Glasgow Coma Scale (GCS) score and findings on computed tomography (CT) and magnetic resonance (MR) imaging of patients with mild head injury presenting GCS scores between 13 and 15. Data were collected from all consecutive patients with mild head injury who were referred to our hospital between July 1 and October 31, 1999. All patients were recommended to undergo CT and MR imaging examinations. Patients younger than 14 years of age were excluded. Ninety patients were recruited into this study. CT scans were obtained in 88 patients and MR imaging were obtained in 65 patients. Of these 90 patients, 2 patients scored 13 points, 5 scored 14 points and 83 (92.2%) 15 points. Patients with GCS score of 13 points demonstrated parenchymal lesions on both CT and MR imaging. Those with 14 points revealed absence of parenchymal abnormality on CT, but presence of parenchymal lesions on MR imaging. Patients in advanced age (chi square test, p
- Published
- 2001
37. Heavily T2 weighted MR assessment of fornical injury after anterior interhemispheric approach for large suprasellar tumors
- Author
-
Akira Yamaura, Kenro Sunami, A. Uozumi, N. Saeki, Motoo Kubota, and Hisayuki Murai
- Subjects
medicine.medical_specialty ,Neoplasm, Residual ,Adolescent ,Mammillary body ,Fornix, Brain ,Anterior commissure ,Central nervous system disease ,Meningioma ,Craniopharyngioma ,Atrophy ,medicine ,Meningeal Neoplasms ,Humans ,Pituitary Neoplasms ,Neuroradiology ,business.industry ,Fornix ,Supratentorial Neoplasms ,Anatomy ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Surgery ,Treatment Outcome ,Female ,Neurology (clinical) ,business ,Craniotomy - Abstract
Fornical injury in transforaminal approach is well known. Its injury in the anterior interhemispheric approach (AIA) has been rarely highlighted. We report 2 cases with a large suprasellar tumor who underwent AIA. Postoperative heavily T2 weighted reversed (T2R) MR images demonstrated its unilateral injury. The clinical significance of symptom-free fornical injury after AIA is discussed. Cases 1 and 2 were a 15 year-old girl with a meningioma and a 49-year-old woman with a craniopharyngioma, respectively. They underwent AIA. Postoperative T2R images revealed unilateral fornical crus atrophy. They did not present associated memory deficits. Case 1 had the injury of both fornical column and anterior commissure. They were speculatively torn by intra-operative lateral retraction of the frontal lobes. Case 2 had unilateral atrophy of the mammillary body and postcommissural fornix, which were probably caused by ischemic damage related to surgical manipulation, since case 2 had an associated anterior thalamic infarct. During the operation for large suprasellar tumors, excessive laterally directed brain retraction should be avoided, since such manipulation may easily tear the overstretched anterior commissure and fornical column. Once we notice or suspect fornical injury on MR studies in cases of re-operation, we have to choose a surgical approach and operative manipulation to preserve an intact fornix. The MR evaluation of fornix should be included in the perioperative radiological assessment, since patients with unilateral fornical injury were free of memory disturbance, and T2R imaging is a useful MR sequence for depicting the anatomy related to the fornix.
- Published
- 2001
38. Criteria for early detection of temporal hemianopia in asymptomatic pituitary tumor
- Author
-
Naoya Fujimoto, O Miyauchi, N Saeki, and Emiko Adachi-Usami
- Subjects
Adenoma ,Adult ,Male ,medicine.medical_specialty ,genetic structures ,Adolescent ,Eye disease ,Optic chiasm ,Asymptomatic ,Sensitivity and Specificity ,Severity of Illness Index ,Pituitary adenoma ,medicine ,Humans ,Pituitary Neoplasms ,Aged ,medicine.diagnostic_test ,business.industry ,Pituitary tumors ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,eye diseases ,Visual field ,Surgery ,Ophthalmology ,medicine.anatomical_structure ,Hemianopsia ,Visual Field Tests ,Female ,Radiology ,medicine.symptom ,Visual Fields ,business - Abstract
Purpose To determine new criteria for early detection of temporal hemianopia in patients with asymptomatic pituitary tumor. Methods Fifteen patients without visual symptoms had pituitary tumor and subtle defects or normal visual fields by Goldmann perimetry. Twelve patients with visual symptoms had pituitary adenoma and visual field defects detected by Goldmann perimetry. All were examined by automated perimetry. The relationship between the tumor and the optic chiasm was graded by magnetic resonance imaging (MRI) on a scale of 0–4. Grade number increased with extent of compression. Temporal hemianopia observed by automated perimetry was estimated from normal data (52 normal fields). Vertical step was determined from the number of adjacent pairs along the midline; sensitivity was lower in the temporal field than in the nasal field. Temporal depression was calculated by the quadrant sum of sensitivity. Results All patients with symptomatic pituitary adenoma had vertical step and temporal depression in the upper field. Nine of 15 patients without visual symptoms had vertical step or temporal depression. Of nine patients with temporal hemianopia, two of four patients had grade 1 compression, three of five had grade 2, and four of four had grade 3. Conclusion New criteria by automated perimetry could detect temporal hemianopia in patients with asymptomatic pituitary tumor.
- Published
- 2001
39. Influences of venous involvement on postoperative brain damage following the anterior interhemispheric approach
- Author
-
Akira Yamaura, Yoshinori Ozawa, Junichi Ono, N. Saeki, and Motoo Kubota
- Subjects
Cerebral veins ,Adult ,Male ,medicine.medical_specialty ,Neurology ,Brain damage ,Neurosurgical Procedures ,Central nervous system disease ,Lesion ,Postoperative Complications ,medicine ,Humans ,Neuroradiology ,business.industry ,Brain Neoplasms ,Phlebography ,Middle Aged ,medicine.disease ,Cerebral Veins ,Surgery ,Cerebral Angiography ,Cerebrovascular Circulation ,Drainage ,Brain Damage, Chronic ,Female ,Neurology (clinical) ,Neurosurgery ,medicine.symptom ,business ,Venous return curve - Abstract
The anterior interhemispheric approach offers us an excellent surgical view for suprasellar lesions. Following this approach, we occasionally encounter postoperative brain damage in the frontal lobes. To assess the determinants of such a complication, we undertook a clinical study.Potential causes for such brain damage were evaluated in 28 consecutive patients with suprasellar tumours extirpated using this approach. We focused particularly on the influences of venous involvement during surgery. The draining territory index (DTI) was originally devised for estimating the extent of the draining area of the sacrificed bridging veins.CT evident brain damage was observed in five of 28 patients (17.8%), but only one patient (3.6%) showed clinically significant postoperative deficits. The patient's age, tumour pathology, tumour character, tumour size, duration of surgery, and radicality of the surgery did not affect the incidence of the brain damage. Of the twelve patients whose bridging veins were sacrificed during surgery, four (33.3%) showed brain damage in the frontal lobes. In contrast, such damage was observed in only one patient out of 16 (6.3%) whose bridging veins were preserved. Among the brain-damaged group, the average DTI of the sacrificed veins was significantly higher than that among the non-brain-damaged group.Venous involvement during surgery significantly aggravated postoperative brain damage following the anterior interhemispheric approach. The DTI was useful in predicting the risk of brain damage, and a large bridging vein with a DTI over 50% should not be sacrificed during surgery.
- Published
- 2001
40. Proliferation, vascular endothelial growth factor expression and cavernous sinus invasion in growth hormone secreting pituitary adenomas
- Author
-
Akira Yamaura, N. Saeki, T. Iuchi, and Katsunobu Osato
- Subjects
Adenoma ,Adult ,Male ,Vascular Endothelial Growth Factor A ,Pathology ,medicine.medical_specialty ,Angiogenesis ,Endothelial Growth Factors ,Pituitary neoplasm ,Neovascularization ,chemistry.chemical_compound ,medicine ,Humans ,Neoplasm Invasiveness ,Pituitary Neoplasms ,Aged ,Lymphokines ,biology ,business.industry ,Human Growth Hormone ,Vascular Endothelial Growth Factors ,Middle Aged ,Debulking ,medicine.disease ,Magnetic Resonance Imaging ,Vascular endothelial growth factor ,Vascular endothelial growth factor A ,chemistry ,Ki-67 ,biology.protein ,Surgery ,Cavernous Sinus ,Female ,Neurology (clinical) ,medicine.symptom ,business ,Cell Division - Abstract
Surgical cure of growth hormone producing pituitary adenomas (GHomas) becomes difficult when they invade the cavernous sinus (CS). Tumour proliferative activity and angiogenesis are thought to be required for tumour growth and invasion, and vascular endothelial growth factor (VEGF) activates neovascularization around tumours. In this study, the mechanism and clinical significance of CS invasion is analysed. In 25 surgically treated GHomas, the extent of CS invasion was classified as high (Knosp's grade 3 and 4), and low (grade 0, 1 and 2) MR grades, and the MR grades were compared with tumour proliferative potential (Ki-67 expression), angiogenetic demand (VEGF expression), volume of adenomas and serum hormone levels. The Ki-67 index of high MR grade adenomas (1.17 +/- 0.62%) was significantly higher than that of low MR grade adenomas (0.55 +/- 0.42%, p = 0.027), whereas VEGF expression showed no significant correlation with MR grades (p > 0.999). Tumour volume also showed a significant correlation with MR grade (p = 0.002). VEGF expression was not correlated with serum hormone level and volume, but was correlated with tumour proliferative potential. Proliferative potential and tumour volume were two independent factors related to CS invasion. Although VEGF expression was not a direct factor related to CS invasion, it may indirectly play a role in activation of tumour aggressiveness, which is required in CS invasion. Our results show that high MR grade adenomas have higher proliferative ability. In order to improve the surgical outcome, preoperative medical debulking is indicated, particularly, in such adenomas.
- Published
- 2001
41. Postoperative radiation therapy for pituitary adenoma
- Author
-
K, Isobe, M, Ohta, S, Yasuda', T, Uno, R, Hara, N, Machida, N, Saeki, A, Yamaura, N, Shigematsu, and H, Ito
- Subjects
Adenoma ,Adult ,Male ,Adolescent ,Disease-Free Survival ,Pituitary Hormones, Anterior ,Humans ,Life Tables ,Pituitary Neoplasms ,Prolactinoma ,Postoperative Period ,Child ,Aged ,Proportional Hazards Models ,Dose-Response Relationship, Radiation ,Neoplasms, Second Primary ,Radiotherapy Dosage ,Middle Aged ,Prognosis ,Combined Modality Therapy ,Neoplasm Proteins ,Treatment Outcome ,Female ,Radiotherapy, Adjuvant ,Dose Fractionation, Radiation ,Germinoma ,Neoplasm Recurrence, Local ,Follow-Up Studies - Abstract
We evaluated the efficacy of postoperative radiation therapy (RT), prognostic factors for local control probability, dose response relationship and treatment sequelae in 75 patients with pituitary adenoma.A total dose of 48-60 Gy (median: 50 Gy) was delivered with a conventional fractionation schedule after surgery. Of 75 patients, 55 (73%) were followed for more than 5 years and 27 (36%) were followed for more than 10 years with a median of 95 months.Five- and 10-year local control probabilities were 87.1% and 85.0%, respectively. Univariate analysis revealed that age (p = 0.007), tumor volume smaller than 30 cm3 (p = 0.018) and the absence of prolactin secretion (p = 0.003) were significantly favorable prognostic factors for local control probability. After multivariate analysis combining these 3 factors, tumor volume smaller than 30 cm3 (p = 0.017) and age (p = 0.039) were statistically significant. Patients with prolactinoma greater than 30 cm3 showed particularly poor local control rates. No significant improvement of the local control rate was detected with increasing total irradiation doses between 48 and 60 Gy (p = 0.29). The most common side effect was hypopituitarism, and there were no severe sequelae such as optic neuropathy or brain necrosis.Except with prolactinoma, the dose of postoperative RT for pituitary adenoma should not exceed 50 Gy. Large prolactinoma, however, was very difficult to control with the irradiation doses between 50 and 60 Gy, and would be good candidates for stereotactic radiosurgery or stereotactic radiation therapy.
- Published
- 2000
42. Bone window CT evaluation on nasal cavity for transsphenoidal reoperations: a sequel to a previous publication
- Author
-
N, Saeki, A, Yamaura, T, Iuchi, and K, Sunami
- Subjects
Adenoma ,Adult ,Male ,Reoperation ,Adolescent ,Humans ,Female ,Pituitary Neoplasms ,Middle Aged ,Nasal Cavity ,Tomography, X-Ray Computed ,Aged - Published
- 2000
43. Brain stem contusion due to tentorial coup injury: case report and pathomechanical analysis from normal cadavers
- Author
-
K. Sunami, Akira Yamaura, and N. Saeki
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,Shortest distance ,Minor injury ,Injury control ,Poison control ,Autopsy ,Central nervous system disease ,Cadaver ,Mesencephalon ,Cerebellum ,Pons ,Medicine ,Humans ,In patient ,Dominance, Cerebral ,Brain Concussion ,Neurologic Examination ,Brain Mapping ,business.industry ,General Medicine ,Anatomy ,medicine.disease ,Magnetic Resonance Imaging ,Biomechanical Phenomena ,Surgery ,Neurology (clinical) ,business ,Tomography, X-Ray Computed ,Brain Stem - Abstract
This report is in two parts. First, a case report on a 20-year-old man with a localized brain stem contusion. Second, in order to elucidate the mechanism of this injury, an anatomical study was performed. Ten cadaver heads were analysed to reveal the variations of spatial anatomy around the tentorial incisura. The lateral tentorial incisura (lateral to brain stem) was situated at the level of pontomesencephalic junction and nearest to the brain stem along its course. The shortest distance between them averaged 1.0 mm (0-4 mm). Based on these findings, primary brain stem injury caused by tentorial incisura occurs at its lateral portion due to the shortest distance to the brain stem and near the level of pontomesencephalic junction. In patients with a tentorial incisura closely related to or touching the brain stem, tentorial coup injury to the brain stem may occur even with a relatively minor injury. In our case, repeated CT and MRI proved that the location of contusion was at the pontomesencephalic junction, coinciding with the level of the tentorial edge. The injury started at the surface of brain stem. The tentorial edge was close to brain stem in this case. These radiological findings support the hypothesis that the brain stem contusion was caused by a tentorial coup injury.
- Published
- 2000
44. Detection of Unstable Plaques in Patients with Carotid Stenosis using B-Mode Ultrasonography
- Author
-
Akira Yamaura, Eiichi Kobayashi, Shinji Hirai, N. Saeki, I. Yamakami, and J. Ono
- Subjects
medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Stent ,Echogenicity ,Original Articles ,030204 cardiovascular system & hematology ,medicine.disease ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Stenosis ,0302 clinical medicine ,Embolism ,Fibrosis ,medicine ,cardiovascular system ,In patient ,Radiology ,cardiovascular diseases ,Complication ,business ,Stroke - Abstract
Distal embolism is a detrimental complication of stent placement for the carotid artery stenosis. To evaluate usefulness of B-mode ultrasonography (US) for the detection of unstable plaques in patients with carotid artery stenosis, we examined US in 46 arteries of 35 patients with carotid stenosis of >30%. The echogenicity of 46 carotid plaques was hyperechoic in 20 plaques, hypoechoic in 15, and mixed-echoic in 11. The echogenicity of carotid plaques was correlated with severity of carotid stenosis, ipsilateral stroke or T1A, heart attack, and risk factors of systemic atherosclerosis. Hypoechoic plaques were associated with severe carotid stenosis and ipsilateral ischemic event. Mixed-echoic plaques had a high incidence of past history of heart attack. Hyperechoic plaques were less likely to associate with risk factors of systemic atherosclerosis. We developed a new method of echodensity analysis. Using a computer software, echodensity values of seven plaque components were determined by comparing US findings and pathology of surgical specimens. The echodensity value was defined as a relative value to the arterial lumen. The calcified part of plaques had the highest echodensity of 6.24 ± 0.86 (mean ± 2 S.D.); fibrosis or hyarynoid degeneration of 2.05 ± 0.40, foamy histiocytes of 1.47 ± 0.05, necrosis of 1.32 ± 0.16, cholestelin clefts of 1.28 ± 0.13, intraplaque hemorrhage of 1.02 ± 0.09, and intraluminal thrombus of 1.27 ± 0.07. Constructed from the echodensity value, an echo-densitometry color mapping of the carotid plaque illustrated the exact location and extent of plaque component. B-mode US of carotid plaques represents clinical characteristics relating distal embolism and systemic atherosclerosis. A new method of echodensity analysis and echo-densitometry color mapping of the carotid plaque is useful to detect unstable plaques in patients with carotid stenosis.
- Published
- 2000
45. Neuroradiological characteristics of pineocytoma and pineoblastoma
- Author
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N. Saeki, K. Sunami, Akira Yamaura, Michio Nakamura, Yasuo Iwadate, and Katsunobu Osato
- Subjects
Adult ,Male ,medicine.medical_specialty ,Pathology ,Corpus callosum ,Pineal Gland ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Neuroradiology ,Pineoblastoma ,medicine.diagnostic_test ,business.industry ,Pineocytoma ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Contrast medium ,Pinealoma ,Female ,Neurology (clinical) ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Tomography, X-Ray Computed ,Calcification - Abstract
We reviewed neuroradiological images in two histologically proven cases of pineocytoma and three of pineoblastoma to delineate the characteristic features of these rare tumours. CT revealed isodense or slightly hyperdense masses with central or peripheral calcification; enhancement with contrast medium tended to be homogeneous in pineocytomas and heterogeneous in pineoblastomas. In the pineocytomas, T1-weighted images revealed rounded, sometimes or slightly lobulated low-signal masses with strong, homogeneous contrast enhancement. Their margin was clear, without invasion of adjacent structures. In the pineoblastomas, however, T1-weighted images revealed multilobulated tumours with heterogeneous contrast enhancement. All three pineoblastomas had poorly defined margins with adjacent structures such as the posterior thalamus or corpus callosum, suggesting a more invasive nature. T2-weighted images revealed nonspecific high signal lesions in all five cases.
- Published
- 2000
46. Albumin permeability across endothelial cell monolayer exposed to reactive oxygen intermediates: involvement of reversible functional alteration of the cell membrane Ca2+ channels
- Author
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N, Saeki, T, AzMa, K, Fujii, M, Kawamoto, and O, Yuge
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Xanthine Oxidase ,Cell Membrane Permeability ,Swine ,Cell Membrane ,Free Radical Scavengers ,Pulmonary Artery ,Calcium Channel Blockers ,Catalase ,Glutathione ,Xanthine ,Dithiothreitol ,Cytosol ,Nickel ,Albumins ,Animals ,Calcium ,Dimethyl Sulfoxide ,Calcium Channels ,Endothelium, Vascular ,Egtazic Acid ,Cells, Cultured ,Chelating Agents ,Phenanthrolines - Abstract
This study was designed to test the idea that the redox state of sulfhydryl (SH)-groups in cell-membrane Ca2+ channels plays a pivotal role in Ca2+ influx, which in turn causes an increase in albumin permeability across the cultured monolayer of porcine pulmonary artery endothelial (PPAE) cells exposed to xanthine/xanthine oxidase (X/XO). Albumin permeability as well as the concentration of intracellular Ca2+ ([Ca2+]i) was increased by X/XO. A H2O2 scavenger (catalase), an iron chelator (o-phenanthroline), and a hydroxyl radical scavenger (dimethyl sulfoxide) inhibited these changes provoked by X/XO, in which intracellular iron-catalyzed hydroxyl radical generation was suggested to be involved. The increase in albumin permeability and [Ca2+]i continued once the PPAE cells were exposed to X/XO. The [Ca2+]i was decreased by a Ca2+ channel blocker, Ni2+, while the removal of Ni2+ increased [Ca2+]i again, suggesting the sustained Ca2+ influx through cell-membrane Ca2+ channels was responsible for the [Ca2+]i elevation. Ni2+ failed to inhibit albumin permeability sustained after the removal of X/XO. In contrast, SH-reducing agents (dithiothreitol and glutathione) inhibited the sustained permeability as well as Ca2+ influx. We concluded that the redox alteration of SH-groups in cell-membrane Ca2+ channels was involved in the increase in albumin permeability after exposure of the endothelial cells to oxidative stress.
- Published
- 2000
47. Toxoplasmic encephalitis in patients with acquired immunodeficiency syndrome--four case reports
- Author
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S, Nakazaki, N, Saeki, S, Itoh, K, Osato, O, Watanabe, N, Hamada, H, Mitsuhashi, H, Shin, I, Kiuchi, C, Kobayashi, A, Yano, and A, Yamaura
- Subjects
Adult ,Male ,Epilepsy ,AIDS-Related Opportunistic Infections ,Brain Neoplasms ,AIDS Serodiagnosis ,Middle Aged ,Magnetic Resonance Imaging ,Diagnosis, Differential ,Paresis ,Fatal Outcome ,Treatment Outcome ,Toxoplasmosis, Cerebral ,Encephalitis ,Humans - Abstract
Four patients, all males aged 40-64 years, presented with toxoplasmic encephalitis associated with human immunodeficiency virus (HIV) infection manifesting as nonspecific neurological deficits such as epilepsy or hemiparesis. Magnetic resonance imaging showed single or multiple lesions with ring enhancement, mimicking metastatic brain tumor or brain abscess. Marked eosinophilia was noted in three patients. Two patients who received anti-toxoplasma chemotherapy in the early stage had a good outcome. However, the other two patients suffered rapid neurological deterioration and needed decompressive surgery, resulting in a poor outcome. Toxoplasma diffusely infects the whole central nervous system from the early stage. The outcome for patients who needed emergency surgery was poor. Therefore, this rare but increasingly common infectious disease must be considered in the differential diagnosis of a patient with neuroimaging findings similar to those of metastatic tumor or brain abscess. Appropriate chemotherapy should be started immediately after HIV-positive reaction is identified in patients with single or multiple mass lesions with ring enhancement.
- Published
- 2000
48. Differential action of spasmolytic vasodilators on platelet aggregation and endothelial cell-dependent anti-aggregation
- Author
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T, Az-Ma, N, Saeki, and O, Yuge
- Subjects
Nitroprusside ,Dose-Response Relationship, Drug ,Platelet Aggregation ,Swine ,Vasodilator Agents ,Diltiazem ,Nicardipine ,Nitroglycerin ,Papaverine ,Sympatholytics ,Animals ,Endothelium, Vascular ,Alprostadil ,Pentobarbital ,Aorta ,Cells, Cultured ,Platelet Aggregation Inhibitors - Abstract
The perioperative use of spasmolytic vasodilators during reconstructive or vascular surgery is an important therapeutic procedure to prevent vascular spasm. Platelet aggregation at vascular endothelium injured by the surgical manipulation is thought to be associated with the persistency of spasm, although little is known about the effects of these drugs on platelet aggregation and on anti-aggregation provoked by endothelial cells.(1) To test the direct effect of vasodilators against platelet aggregation, change in light transmission through platelet-rich plasma (PRP) stimulated with 4 microg/ml collagen was measured in the absence or presence of pentobarbital, papaverine, prostaglandin E1 (PGE1), trinitroglycerin, nitroprusside, nicardipine, and diltiazem. (2) Effects of these drugs on endothelial cell-dependent anti-aggregation were then evaluated. Incubation buffer of cultured porcine aortic endothelial (PAE) cells, which were preincubated with vasodilators for 10 min prior to a 1-min stimulation with 1 microM bradykinin, was transferred to collagen-stimulated PRP.(1) Papaverine and PGE1 directly inhibited platelet aggregation in a concentration-dependent manner. All other drugs failed to inhibit aggregation. (2) Incubation buffer of PAE cells stimulated with bradykinin showed a potent anti-aggregation. Pentobarbital concentration-dependently inhibited the endothelial cell-dependent anti-aggregation. Every other drug did not inhibit the anti-aggregation by PAE cells.Because of the direct anti-aggregatory effect without inhibiting endothelial cell-dependent anti-aggregation, we suggested that papaverine and PGE1 were the most promising vasodilators of all drugs examined in this study while further evaluation is required for the clinical relevance of the present study.
- Published
- 2000
49. Early Age Fracture Behavior of Hybrid Fiber-Reinforced Concrete
- Author
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N W Kim, T Horiguchi, and N Saeki
- Subjects
Polypropylene ,Mass concrete ,Strain energy release rate ,Materials science ,Fracture mechanics ,Fiber-reinforced concrete ,law.invention ,chemistry.chemical_compound ,Cracking ,chemistry ,law ,Fracture (geology) ,Composite material ,Shrinkage - Abstract
Controlling and mitigating cracks in concrete is one of the main problems in construction engineering. In this work, improvement of crack resistance against thermal stress and shrinkage of the mass concrete at an early age were studied using a hybrid fiber reinforced concrete (FRC). The fibers used were steel and polypropylene fibers with lengths of 6, 12, and 30 mm. Physical properties as well as crack resistance capabilities of the hybrid FRC were evaluated. As a result of this research, a strain energy release rate, calculated by fracture mechanics, is proposed.
- Published
- 2000
50. Sleep-disordered breathing in acromegalics--relation of hormonal levels and quantitative sleep study by means of bedside oximeter
- Author
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N, Saeki, S, Isono, T, Nishino, T, Iuchi, and A, Yamaura
- Subjects
Adult ,Male ,Sleep Apnea Syndromes ,Growth Hormone ,Acromegaly ,Humans ,Female ,Oximetry ,Insulin-Like Growth Factor I ,Middle Aged ,Biomarkers - Abstract
Sleep-disordered breathing (SDB) is common in patients with growth hormone (GH) secreting pituitary adenomas. Since long-term untreated SDB aggravates systemic conditions (hypertension and arrhythmia etc.), the therapeutic outcome of SDB is important in reducing morbidity and mortality rates. But the results of a quantitative analysis of the lowered GH and IGF-1 levels in SDB in a relatively large number of patients are not detailed. Ten consecutive acromegalic patients were studied with a bedside oximeter. Preoperatively they were divided into two groups based on the presence (SDB group = 6 patients) or absence (non-SDB group = 4 patients) of clinical symptoms of SDB such as habitual snoring, excessive daytime somnolence and nocturnal apneic episodes. The serum IGF-1 averaged 931.7 ng/ml in SDB group and 898.3 ng/ml in non-SDB group. The oxygen desaturation index (ODI) (the number of oxygen desaturations exceeding 4% from the base line) was 29.1+/-15.4 in the SDB group and 2.5+/-1.8 in the non-SDB group (P=0.01). Other oximeter parameters such as the percent of the time spent at O2 saturation90% and the mean and the lowest O2 saturations closely correlated with the degree of the clinical symptoms. A postoperative sleep study was conducted in 5 patients in the preoperative SDB group, 4 months or more after the surgery. The serum GH and IGF-1 levels normalized in 3 patients but remained slightly high in 2. ODI became 9.1+/-5.6, which was significantly lower than the preoperative value (P=0.026). One patient had a complete clinical resolution. The other 4 obtained slight to moderate improvement clinically and oximetrically despite normalized or decreased hormonal levels. This study clarified that the response of SDB to lowering of the GH level varies from one patient to another and persisting SDB despite the normalization of the hormonal levels suggests the involvement of other factors in the production of SDB.
- Published
- 1999
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