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T Tazawa

Publications and source records attributed to T Tazawa.

At least 55 records · Page 3Linked to original sources

Cell differentiation in human anagen hair and hair follicles studied with anti-hair keratin monoclonal antibodies.

By a hybridoma technique using BALB/c mice and Sp2/0-Ag14 mouse myeloma cells, monoclonal antibodies against hair fibrous proteins (HFP) were produced. Two monoclonal antibodies, designated as HKN-5 and HKN-7, were chosen. Either HFP or epidermal fibrous proteins (EFP) were electrophoretically separated on polyacrylamide gels with sodium dodecyl sulfate. By immunoblot analyses, HKN-5 and HKN-7 decorated the electrophoretic bands of HFP but not those of EFP. Immunohistochemically, these monoclonal antibodies stained the medulla, cortex, cuticle, and inner root sheath in the keratogenous zone of anagen hairs, but not hair matrix cells. HKN-5 further reacted with the innermost cells (IMC) of the outer root sheath; these cells formed a single cell layer located outside of the Henle's layer. HKN-7 did not react with the outer root sheath including the IMC. Neither monoclonal antibody reacted with any other skin components or any tissues of other organs examined. Ultrastructurally, the IMC of the outer root sheath showed a unique cell differentiation forming an independent cell layer. It is suggested that the cells in the medulla, cortex, cuticle, and inner root sheath of anagen hair and hair follicles possess a similar keratin expression and that the IMC of the outer root sheath display a unique keratin expression and their own cell differentiation, resulting in 2 types of keratinization of the outer root sheath; keratinization of IMC and trichilemmal keratinization.

Animals↗

Immunological characteristics and histological distribution of human hair fibrous proteins studied with anti-hair keratin monoclonal antibodies HKN-2, HKN-4, and HKN-6.

By use of a mouse hybridoma technique, monoclonal antibodies were produced against hair fibrous proteins, which were extracted from normal human hairs. Three monoclonal antibodies, designated as HKN-2, HKN-4, and HKN-6, were chosen and used to investigate the immunological characteristics of hair fibrous proteins. Epidermal fibrous proteins were also extracted from human sole callus horny materials. Hair or epidermal fibrous proteins were electrophoretically separated on polyacrylamide gels with sodium dodecyl sulfate. By immunoblot analyses, HKN-2 and HKN-4 marked the electrophoretic bands of both proteins; however, HKN-6 reacted only with the bands of hair fibrous proteins. Immunohistochemically, all three monoclonal antibodies stained the keratogenous zone of anagen hairs. HKN-6 did not react with any other skin components or with tissues of other organs examined. Although HKN-2 showed reactions with skin epithelial tissues, except for epidermal basal cells and secretory cells of sweat glands, the reactivity of HKN-2 was limited within the skin. HKN-4 displayed a broad crossreactivity with all of the skin epithelial cells and various epithelial cells of other organs. These findings indicate that some components of hair fibrous proteins are immunologically specific to hair cells, whereas others broadly crossreacted with the fibrous proteins of other skin epithelial cells or with those of various epithelial cells. The anti-hair keratin monoclonal antibodies seem useful to examine the differentiation patterns of epithelial cells and tissues.

Antibodies, Monoclonal↗

[Use of real-time ultrasonography in neurosurgical operations].

The authors' experience with the application of real-time ultrasonography during 29 and after 3 neurosurgical operations is reported. Intraoperative sonography was performed in 29 cases. The neurosurgical operations include aneurysm surgery in 13 cases, removal of intracerebral hematoma in 11 cases, neoplasm surgery in 2 cases, and so on. Moreover, sonographic examination through bone defect was performed in 3 cases after decompression craniectomy. The instrument used was an ATL (Advanced Technology Laboratories, Bellevue, WA, USA) mechanical sector scanner of which scanhead contained transducers of three frequencies: 3, 5 and 7.5 MHz. The scanhead was wrapped with a sterile rubber bag after acoustic coupling gel had been applied to the head's tip. Then the scanhead was placed on the dura and ultrasonic examination was performed. The result was that the lesion was clearly identified and localized in all cases except for three cases of mild subarachnoid hemorrhage. In addition, in the two cases of needle aspiration of cyst or hematoma, the needle was easily identified and needle aspiration was performed safely and accurately. Moreover, during aneurysm surgery, aneurysm itself was detected in two cases by the real-time ultrasonic imaging. Especially, in the case with large aneurysm of the left middle cerebral artery, the findings about the aneurysmal wall, that is to say, which part is thick and which part is thin, could be obtained. Prior to the operation of aneurysm, cerebral angiogram and computerized tomographic scan are always examined thoroughly, but information about aneurysmal wall can be rarely obtained by them.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Some considerations on surgical approaches to the anterior communicating artery aneurysms--radiological study of 122 cases].

We studied the operative approaches to anterior communicating artery aneurysms by means of reviewing preoperative angiogram and operation records. During the past 5 years, 117 patients with anterior communicating artery aneurysms were operated on in our hospital. Among these, we examined 112 cases of which preoperative angiogram and operation records were satisfactory for this study. We checked the next points on the preoperative angiograms. Neck of aneurysm-planum sphenoidal distance. Direction of the anterior communicating artery. It means which A2 is anterior to the other A2 in the lateral view of angiogram. Size of aneurysm. We checked the next points on the operation records. Operative approach and the side of craniotomy. When the pterional approach was taken, the rectal gyrus was aspirated or not. This analysis derived these two conclusions as below. 1. In the literature, as the operative approach to anterior communicating artery aneurysm, the pterional approach has a lot of advantages. For example, the pterional approach was accomplished without extensive frontal lobe retraction, without mobilization of the temporal lobe, without sacrificing the olfactory tract, and so on. Moreover, in early stage after onset of SAH, it is possible to remove the subarachnoid blood extensively without obvious brain damage by the pterional approach. In this study, we paid attention to the correlation between the neck-planum sphenoidal distance and the fact of aspiration of the rectal gyrus in the pterional approach. The result is that the higher aneurysmal neck was, the more frequently the rectal gyrus was aspirated. So, if the neck-planum sphenoidal distance is under 12 mm, which includes the majority of the cases (94% of cases), we think the pterional approach is the best approach for anterior communicating artery aneurysm.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Relationship between contrast enhancement on computed tomography and cerebral vasospasm in patients with subarachnoid hemorrhage.

To elucidate the relationship between abnormal enhancement of the cisterns on computed tomography and cerebral vasospasm, we performed a systematic and prospective study in 60 patients with ruptured cerebral aneurysms. There is a significant relationship between the findings of contrast-enhanced computed tomography (CECT) within Day 3 of rupture and cerebral vasospasm. Among 37 patients undergoing CECT between Day 0 and Day 3, 17 (46%) showed prominent increases in density in the region around the circle of Willis and its branches. In 13 of 17 cases (76%), severe vasospasm with motor paralysis occurred. In the remaining 4 cases (24%) with only slight or no cerebral vasospasm, the hematoma in the subarachnoid space was removed surgically by Day 3. In 19 of 20 cases without remarkable CECT, no severe cerebral vasospasm with motor paralysis occurred. There is no significant relationship between the CECT findings after Day 3 and cerebral vasospasm. The results indicate that the prominent increase in density in the region of the circle of Willis and its branches often observed on CECT within Day 3 of subarachnoid hemorrhage is useful for prediction of the occurrence of cerebral vasospasm and also provide information on the pathogenesis of cerebral vasospasm.

Aged↗

Intraoperative use of real time ultrasonography applied to aneurysm surgery.

The intraoperative application of real time ultrasonography during 13 neurosurgical operations for intracranial aneurysms is reported. In 2 cases, the aneurysms themselves could be detected clearly by real time ultrasonic imaging. In the case of a large aneurysm, information about the nature of the aneurysmal wall was obtained. Other lesions coexisting with the aneurysm (namely, intracerebral hematoma, massive subarachnoid hemorrhage, and hydrocephalus) could be recognized clearly. Real time intraoperative ultrasonography is considered to be useful in aneurysm surgery.

Adult↗

[Dynamic pathophysiology of cerebral infarction and revascularization. III. Changes of regional cerebral blood flow].

Thirty-eight patients with occlusive cerebrovascular disease were followed with regional cerebral blood flow (rCBF) measurement, angiography and computerized tomography (CT) to know the time course of rCBF in cerebral infarction. The rCBF study was carried out by the 133Xe intracarotid injection method with 16 scintillation detectors. They were allocated to two groups according to the findings on angiograms; 15 patients having any change of occlusive lesion (the group of no-recanalization ) and 23 patients showing reopening of occluded vessels (the group of recanalization). A mass sign and an extent of cerebral infarction were observed on CT. In the group of no-recanalization, a mean value of rCBF (mean rCBF) in acute stage was well correlated to the severity of ischemic stroke. In minor completed strokes the average mean rCBF was 35.8 +/- 3.7 ml/100g/min, which is significantly higher than that in major strokes and progressing strokes of 24.8 +/- 3.9 ml/100 g/min (p less than 0.001). Sequential change of mean rCBF was not prominent in the group of no-recanalization. However, rCBF change was conspicuous in the group of recanalization. In acute stage of recanalization, rCBF were markedly affected by the presence of mass sign (cerebral edema) on CT. When CT showed midline shift of structure, mean rCBF was markedly reduced, and when without midline shift, focal hyperemic areas were sometimes observed in the revascularized area. Thus, the inhomogeneity of rCBF was characteristic in cases with recanalization. The focal hyperemia usually disappeared within one week in cases of minor stroke and lasted until 2 or 3 weeks in cases of major stroke. In chronic stage, mean rCBF decreased, and there was no significant difference of averaged rCBF between two groups. Those findings suggests that the main factor influenced on the sequential change of rCBF is reopening of occluded vessels. Regional CBF may depends both on the degree of cerebral edema and the extent of vasoparesis after revascularization. In chronic stage CBF value is not always dependent to the presence of occlusive lesion but might be reflected in the total brain function.

Aged↗

Separation and purification of (Cd, Cu, Zn)-metallothionein in carp hepato-pancreas.

1. Cd-binding protein was isolated from the hepato-pancreas of carp administered CdCl2 (2 mg/kg). 2. This protein had a high absorption at 254 nm derived from Cd-mercaptide binding, and a low absorption at 280 nm derived from the absence of aromatic amino acids; the authors recognized the presence of two types. 3. The amino acid composition of the proteins was determined. The contents of cysteine residues were 34.24% and 31.90% in MT-I and -II respectively. Tyrosine, phenylalanine, tryptophan, histidine, leucine and arginine residues were absent in both types.

Amino Acids↗

Formation of metallothionein in fish.

1. Carp were bred in Cd solution, and each organ was homogenized and centrifuged at 105,000 g. The Cd content of the supernatant was much more than that of the precipitate. 2. In examining the metal form in the supernatant, the induction of metallothionein (MT) was found in carp exposed to Cd and Zn solutions and the presence of metallothionein was found in fish captured in Nagara river and breeding ponds. 3. Cd content in the metallothionein fraction of hepato-pancreas increased at the early stages of exposure, but Cd in the metallothionein fraction of the other organs increased as time proceeded. 4. In the tap water group, metallothionein in hepato-pancreas and kidney contained Cu, and increased with the induction of metallothionein in hepato-pancreas due to Zn-exposure.

Animals↗

Protection by metallothionein against cadmium toxicity.

1. The protective effect against Cd toxicity of prior exposure to Cd or Zn solutions at low concentration was studied. 2. Carp were bred in tap water (A), 1 ppm Cd solution (B) and 5 ppm Zn solution (C) for 14 days and then transferred into 15 ppm Cd solution. The survival ratio of carp decreased in the order: (C):(B):(A). 3. Binding capacity of Cd to high molecular and metallothionein fractions in the cytoplasmic solutions of the hepato-pancreas was studied and the binding capacity to the metallothionein fraction was stronger than that to the high molecular fraction. The authors recognized that Zn in the metallothionein fraction is substituted by Cd.

Animals↗

Prevention of vasospasm by early operation with removal of subarachnoid blood.

Sixty-four patients who were operated on within 4 days after acute subarachnoid hemorrhage are included in this study. All patients underwent preoperative computed tomographic (CT) scanning, and the amount and distribution of subarachnoid blood clot were noted. Operation was carried out by the frontobasal lateral approach, and the subarachnoid clot was removed by microsurgical suction-irrigation after clipping of the aneurysm. Immediate postoperative CT scanning was performed to evaluate the completeness of the subarachnoid blood clot removal. The presence or absence of postoperative vasospasm was determined with angiography performed between the 7th and 10th postoperative days. All patients were, of course, also evaluated for evidence of neurological deterioration. Approximately two-thirds of the patients in this series showed high density subarachnoid blood clot on the preoperative CT scan. The postoperative CT scans showed that it was possible to remove the majority of the blood clot except that located in the frontal interhemispheric fissure, the posterior part of the insular cistern on the approached side, and all of the insular cistern on the contralateral side. There was no spasm or only mild spasm in any site where the blood clot had been successfully removed. Delayed neurological deficits occurred only in those cases in which subarachnoid blood clot remained in the cisterns. These results suggest that it is possible to prevent intracranial arterial spasm and associated neurological deterioration by early operation and removal of clotted blood from the subarachnoid space.

Adult↗