Search PubMed⌕ Search

Biomedical subjects

O Watanabe

Publications and source records attributed to O Watanabe.

At least 91 records · Page 5Linked to original sources
PubMed1994

[Cultured Schwann cells in vivo promoting regeneration of peripheral nerves: an experimental study].

It is recognized that Schwann cells produce several substances which promote peripheral nerve regeneration. This study examines the hypothesis that cultured Schwann cells can stimulate axonal regeneration in vivo, using histological and electrophysiological observations. The Schwann cells were collected from the sciatic nerves of 1-day-old Sprague-Dawley strain rats and propagated with cytosine arabinoside and cholera toxin. The purified Schwann cells were then suspended in type I collagen gel and injected into a nerve guide which was made from a silicone tube. The sciatic nerve of other Sprague-Dawley strain rats were then transected, and both nerve stumps were sutured into each end of the nerve guide leaving a 12 mm gap between the stumps. These rats were then divided into three groups; S-1 Group (n = 14) having the tube filled with 10(5) Schwann cells/ml and collagen gel, S-2 Group (n = 34) having the tube filled with 10(7) cells/ml and collagen gel; and C Group (n = 27) having the tube filled only with the collagen gel, as controls. Also, to investigate the survival duration of the cultured Schwann cells, a nerve guide tube (M Group: n = 25) was packed with a millipore membrane at both ends and viability of Schwann cells in the tube was followed.

Animals↗
PubMed1994

Cystic renal cell carcinoma. Imaging findings with pathologic correlation.

Twenty-seven cystic renal cell carcinomas (RCC) in 23 patients were analyzed radiologically and histologically. They were classified into 4 histopathologic growth patterns: a) multilocular (n = 15, 9 with macrocystic and 6 with microcystic components); b) unilocular (n = 3); c) cystic necrosis (n = 9); and d) tumors originating in the wall of a simple cyst (n = 0). Macrocystic multilocular RCC showed multiloculated configuration on ultrasound and contrast enhanced CT. Angiography revealed neovascularity peripherally or within the tumor (7/9 tumors). Microcystic multilocular RCC did not fulfill the criterion for a cystic mass on ultrasound: they were irregularly hyperechoic. There was little enhancement on postcontrast CT and only slight neovascularity on angiography. Unilocular RCC showed a cystic mass with an irregular wall or mural nodules on ultrasound and contrast enhanced CT. Necrotic RCC showed various sonographic findings from anechoic to irregular echoic. The appearance on CT varied from cystic with mural nodules to a multiloculated or irregular architecture. Neovascularity was seen in the periphery in 8 of 9 tumors. Clinically, this type seemed to be the most aggressive.

Adult↗
PubMed1993

Breast cancer in a male patient with prolactinoma.

A 68-year-old man was diagnosed as having left primary breast cancer. Systemic bone roentgenography showed no evident metastasis, however, skull roentgenography revealed ballooning of the sella turcica, suggesting a pituitary tumor, which was subsequently confirmed by computed tomography. Because there was a high serum prolactin level, the pituitary tumor was diagnosed as a prolactinoma. A modified radical mastectomy was performed for the breast cancer, and bromocriptine therapy given for the prolactinoma. Prolactin is known to initiate and promote breast cancer in mice and rats but little is known about its role in human breast cancer. If hyperprolactinemia plays an important role in the tumorigenesis of human breast cancer as it does in mice and rats, the incidence of breast cancer in patients with hyperprolactinemia may be high. To our knowledge, however, only four such cases have been reported. The present rare case of male breast cancer with prolactinoma is discussed with reference to the literature.

Aged↗
PubMed1993

Hyperechoic renal tumors: anechoic rim and intratumoral cysts in US differentiation of renal cell carcinoma from angiomyolipoma.

To determine whether angiomyolipomas (AMLs) and renal cell carcinomas (RCCs) can be differentiated at ultrasonography (US), the authors retrospectively evaluated the sonographic appearances of 31 AMLs and 38 RCCs. Sonograms were evaluated by three radiologists without knowledge of histologic findings, with respect to the echogenicity of the tumor, predominant echotexture, and whether an anechoic rim was present. All patients had also undergone computed tomography (CT) to check for tumoral fat. Intratumoral fat was evident at CT in 28 of the 31 AMLs. RCCs had no fat at CT or histologic evaluation. An anechoic rim was evident in 32 of 38 (84%) RCCs, and 10 RCCs had small anechoic areas with back echo enhancement, which corresponded to intratumoral cysts or cystic necrosis at histologic evaluation. The anechoic rim and areas indicative of cysts were not found in AMLs. Demonstration of an anechoic rim and/or intratumoral cysts in a hyperechoic mass at US suggests that the tumor is an RCC.

Adult↗
PubMed1992

[Clinical evaluation of lumbosacral nerve root and lateral stenosis using coronal MR imaging].

MR imaging is being used more frequently to study the lumbar spine and is becoming the modality of choice in the assessment of patient with low back pain. Using a new technique of coronal and half coronal scan with MR imaging, it was possible to visualize L4, L5 and S1 nerve roots accurately. We described the MR findings of lateral stenosis using this technique. Several characteristic MR findings were identified, and the most important one was nerve root impingement in the intervertebral foramen. We consider that coronal and half coronal scan with MR imaging is useful in diagnosis of lateral stenosis.

Adult↗
PubMed1992

Small renal cell carcinoma: pathologic and radiologic correlation.

The authors correlated the radiologic and pathologic findings of 36 patients with small renal cell carcinoma (less than or equal to 3 cm in diameter). Tumors were discovered incidentally or by means of mass surveys with ultrasound (US). Computed tomography (CT) and angiography were performed before surgery. Of the 36 tumors, 24 were of solid (alveolar) architecture, five were of papillary architecture, three were of tubular architecture, and four were of multilocular cystic architecture. Cell arrangement was closely correlated with radiologic appearance, especially in regard to tumor vascularity and echogenicity. Histologically homogeneous tumors of solid architecture were hypoechoic at US and hypervascular at angiography and contrast medium-enhanced CT. Tumors of papillary, tubular, and multilocular cystic architecture were hyperechoic at US and hypovascular at angiography. There was no correlation of cell differentiation and cell architecture with echogenicity or tumor vascularity. Tumors with hemorrhage showed marked hyperattenuation at CT. A tumor capsule was observed in 25 patients (69%); this was demonstrated as a rim at US or angiography.

Adult↗
PubMed1992

Spontaneous disappearance of arteriovenous fistula between the vertebral artery and deep cervical vein--case report.

A 58-year-old female was readmitted with pulsatile tinnitus in the right ear 8 months after subtemporo-occipital transtentorial clipping of a peripheral superior cerebellar artery aneurysm. On examination, she was normal except for pulsatile bruit over the right mastoid region. Angiography showed a fistulous communication between the muscular branches of the right vertebral artery and the deep cervical vein. The incision of the aneurysm surgery was supratentorial, so the only possible cause of the upper cervical arteriovenous (AV) fistula was fine gold acupuncture needles implanted for bronchial asthma 18 years before. The AV fistula disappeared spontaneously after 1 month, possibly because of thrombosis of the affected veins.

Arteriovenous Fistula↗
PubMed1992

[Application and technique of breast conservative treatment of breast cancer].

In patients with breast cancer who had undergone breast conservative treatment involving lumpectomy, axillary lymph node dissection and irradiation, the surgical results and risk factors for remaining cancer foci in the conserved breast were investigated. This form of surgery was performed in 25 patients with T1,N0,-Ia,M0 breast cancer. The cut end of the resected specimen was histopathologically positive for cancer cells in 48% of the patients, but there has been no local or distant recurrence in any patient to date with a mean follow-up period of 17.2 months after surgery. In most breasts resected after lumpectomy, slight cancer foci remained in mammary glands at the sites within 1.0cm distant from the cut end. Extensive remaining cancer lesions were found among cases with advanced intraductal spread or central necrosis in the intraductal foci. The above findings indicate that breast conservative treatment by lumpectomy may result in histopathologically remaining cancer foci, although these can be controlled by irradiation therapy. However, application for this treatment requires much caution when severe intraductal spread or central necrosis is present in the intraductal foci, because extensive cancer foci may remain postoperatively in such cases.

Adult↗
PubMed1991

The clinical value of tissue carcinoembryonic antigen in breast cancer.

The relationship of tissue carcinoembryonic antigen (CEA) to clinicopathological factors and prognosis was investigated in 168 patients with invasive ductal carcinoma of the breast. Tissue CEA was determined by radioimmunoassay and a level of 5.1 ng/ml or more considered to be positive. Tissue CEA was positive in 31.5 per cent of the patients overall and, of the clinicopathological factors, tumor size and the presence or absence of lymph node involvement were not found to be correlated with tissue CEA. However, the tissue CEA positivity rate was significantly higher in patients who had four or more metastatic lymph nodes (p less than 0.01). Tissue CEA-positive patients showed earlier recurrence than CEA-negative patients (p less than 0.01) and had a poorer outcome (p less than 0.05). Thus, tissue CEA is considered useful as a prognostic index for primary breast cancer patients.

Adult↗
PubMed1991

In vivo sodium-23 MRI in brain tumors: evaluation of preliminary clinical experience.

In vivo sodium-23 magnetic resonance (MR) imaging in the head was performed in ten normal volunteers and six patients with brain tumors on a commercially available 1.5 Tesla whole-body MR system. Although sodium MR signal from the brain parenchyma could hardly be detected on routine spin echo (SE) pulse sequence, free induction decay (FID) image with echo time of 1.9 msec demonstrated MR signal in the normal brain tissue. On the other hand, extracellular sodium of cerebrospinal fluid, large venous sinus, and vitreous humor offered high sodium MR signal intensity due to the quantity of sodium and the relatively longer transverse relaxation time (50-60 msec) compared to that of intracellular sodium (less than a few msec). Strong signal was obtained in gliomas with superior contrast, though the delineation of the tumor tissue from edema was as difficult as when seen on proton T2 weighted SE image. Meningioma itself gave much less of a sodium MR signal compared to glioma. Peritumoral edema associated with meningioma showed a markedly high sodium MR signal which was more prominent adjacent to the tumor, although proton SE image revealed the peritumoral edema as homogeneous. Pathological tissues such as brain tumors and edema could be readily depicted as significantly high sodium-23 MR signal, apparently different from normal brain tissues. The current status of in vivo sodium MR imaging is discussed. The authors concluded that early clinical experience of in vivo sodium-23 MR imaging brought promising results in the evaluation of brain tumors and edema; otherwise, discrimination and quantification of multiple T2 components and the improvement of spatial resolution are desperately needed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Pathogenesis and prevention of gastrointestinal complications following transcatheter arterial embolization].

Prospective evaluation of gastrointestinal complications after transcatheter arterial embolization (TAE) was performed on 149 TAEs of 133 patients with endoscopy in order to evaluate whether the use of antiulcer medication can prevent such complications. In 21 of 141 TAEs (14%) there developed gastrointestinal complications. The incidence of complications with administration of H2-blocker was 30.4%, whereas the incidence with administration of PGE1 and without medication were 2.8% (p less than 0.01) and 9.0%, respectively. It has been suggested that such complications are mainly due to backflow of the embolic materials to the gastric artery. These findings indicates that decrease of gastric mucosal blood flow due to backflow of the embolic materials to the gastric artery cause the gastrointestinal complications.

Anti-Ulcer Agents↗
PubMed1989

[Etiological study of relationship between impacted permanent teeth and malocclusion].

This investigation was undertaken to determine the causes of impacted permanent teeth and whether they have any influence on dentition, occlusion and skeletal patterns. The materials used were dental X-rays, occlusal dental X-rays, panoramic radiograms and cephalograms and dental casts of 194 cases (51 males and 143 females) which revealed impacted permanent teeth among 3979 cases (1215 males and 2764 females) from 1964 to 1985 in the Department of Orthodontics, School of Dentistry, Aichi-Gakuin University. The results obtained were as follows: 1. The incidence of impacted permanent teeth in these samples was 4.9% of the entire number of orthodontic patients. There was no significant difference between sexes. 2. The incidence according to the number of impacted permanent teeth was as follows: one impacted tooth, 74.8%; two impacted teeth; 21.1%, three impacted teeth; 3.6%, four impacted teeth; 0.5%. The incidence of two symmetrically impacted teeth was 61.5%. 3. As to the type of impacted teeth, the frequency of maxillary central incisors was the largest (33.7%), followed by 3 (25.0%), 5 (22.2%), 5 (11.9%), 2 (4.4%), 3 (1.2%), 4 (0.8%), 4 (0.4%), and 7 (0.4%). But no impacted teeth were found in the regions of 1, 2, 6, 6, 7 and 7. 4. As to impacted teeth and the type of malocclusion, the spaced arch in the anterior region had impacted teeth most frequently followed by crowding, open bite and lateral cross bite. Malocclusions with the smallest incidence were cross bite and upper protrusion. The spaced arch had a higher incidence of impacted teeth than bimaxillary protrusion. In the posterior region (impacted molar teeth), the lateral cross bite, spaced arch, and upper protrusion had impacted molars most frequently, crowding was second and cross bite had the least. 5. In the direction of long axis, the impacted tooth with a horizontal direction was found most frequently (35.2%), followed in the order of frequency by inverse direction (32.7%), labial or mesial tipping (22.0%), lingual or distal tipping (5.7%), and right-angled (4.4%). Moreover, the inverse maxillary central incisor and mesially tipped maxillary canine were found most frequently. The frequency of maxillary central incisors with crooked roots was 64.7%, which was higher than that of maxillary canines (19.0%). 6. Lack of space is the most frequently found cause of impacted teeth, and in the anterior region this was the main cause of canine impacted teeth. Eruption impediment by supernumerary teeth and trauma were found to be characteristic causes of anterior impacted teeth.

Adult↗
PubMed1989

[Histopathological study on the safety of conservative breast surgery in terms of the degree of axillary dissection for breast cancer].

The subjects were 15 patients with primary mammary cancer who underwent radical mastectomy. Axillary dissection (level I, II and III) with an incision 7 cm below the axilla was performed. After radical mastectomy, the presence/absence of remaining lymph nodes and fatty tissue was determined. All operations were performed by the same surgeon. The number of lymph nodes dissected by means of subaxillary incision ranged from 10 to 32 (mean 20.4). The proportion of remaining lymph nodes found after radical mastectomy was 0/142 (0%) for level I, 0/113 (0%) for level II and 3/54 (5.6%) for level III. In the subclavian Halsted area, fatty tissue partially remained in 60.0% of the patients and more than half in 13.3%. It was shown that complete dissection of level III lymph nodes is difficult when this surgical technique is employed. Although fatty tissue did remain in some cases after level II dissecting, this technique presented hardly any problems in the case of level I and II dissection. Therefore, from the viewpoint of axillary dissection alone, the present technique can achieve results similar to those obtained by radical mastectomy, suggesting its applicability to mammary cancer at a relatively early stage.

Adipose Tissue↗
PubMed1988

Collet-Sicard syndrome after minor head trauma.

Occipital condyle fractures are rare and are usually associated with severe head and cervical spine injury. A 71-year-old man developed unilateral palsies of the 9th through 12th cranial nerves (Collet-Sicard syndrome) due to a fracture of the occipital condyle, which was diagnosed by computed tomography. He was treated conservatively and made a good recovery.

Accessory Nerve↗
PubMed1988

Radiosensitive hemangiopericytoma of the falx. Case report.

A case of a recurrent hemangiopericytoma of the falx which responded well to radiotherapy is reported. The patient was a 58-year-old woman who received a total of 6000 rads of local Linac irradiation over 6 weeks. One year after completing radiotherapy, a computerized tomography scan showed marked regression of the tumor.

Brain Neoplasms↗
PubMed1987

Establishment of interleukin 2 dependent cytotoxic T lymphocyte cell line specific for autologous brain tumor and its intracranial administration for therapy of the tumor.

Autologous brain tumor specific CTLs were induced from the patient's PBL by a mixed lymphocyte-tumor culture, and were maintained for more than 2 months in a medium containing exogenous IL-2. The autologous T cell line containing specific CTL was administered into the tumor-bed for the treatment of malignant glioma. In 2 cases out of 5, tumors regressed more than 50% in diameter. One of these patients is still alive now with full of his social activities, and it is 104 weeks after the initiation of the immunotherapy. Autologous T cell lines were safely administered in all cases without any complications nor toxicities.

Adolescent↗