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T Yazaki

Publications and source records attributed to T Yazaki.

At least 181 records · Page 10Linked to original sources
PubMed1982

[Nuclear magnetic resonance (NMR) imaging of brain edema from sliced rat brain: preliminary report].

A series of the sliced rat brain were imaged by proton nuclear magnetic resonance (1H-NMR) using a Carr-Purcell-Meiboom-Gill sequence. The slices were obtained from the adult male Wistar rats, normal or suffering from vasogenic brain edema at 2, 6, 24Hr, 2Wk and 2Mo period after the application of cryo-injury. The imaging time was arranged 17 to 22 minutes dependently upon signal to noise ratio. The slice thickness was 1.2 mm, and pixel dimensions were 0.2 X 0.2 mm. Whereas a voxel size in our images is mere 1/1,200 compared to that reported about the prototype human NMR imaging devices, high resolution has been realized. The spatial resolution is very fine, as evidenced by the appearance of major internal structures of rat brain, and the object contrast is so high that cerebral white-gray contrast is excellent, although the difference in water concentration between them is only 7%. It has been impossible to measure serially in vivo change in water concentration of small organs as rat brain, NMR has the capability to generate images in response to tissue state of hydration, therefore we can easily recognize the extent and intensity of the brain edema, which has been defined as an expansion of the brain volume resulting from an increase in its fluid content. And in this study, using the prototype mini-NMR-CT of excellent spatial and contrast resolution, we have been able to show this advantage of NMR as a new tool for research in the field of neurological surgery.

Animals↗
PubMed1981

Soluble skin test antigen of varicella-zoster virus prepared from the fluid of infected cultures.

A soluble varicella virus antigen for skin testing was developed using culture fluid from varicella-zoster virus-infected human diploid cells. The culture fluid was centrifuged at a high speed (100,000 g for 2 hr) to remove viral particles, and the supernatant, after heating at 56 C for 30 min, was used as the soluble skin test antigen. No virion or nucleocapsid was found by electron microscopy, and very little 3 H-labeled DNA in the soluble antigen hybridized with viral DNA. By immunoprecipitation, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and fluorography, several viral glycoprotein bands were detected in the soluble antigen. In a comparative skin test on 10 medical students and 10 children using soluble and crude antigens prepared from culture fluid or infected cells, the skin reaction to the soluble antigen tended to be less than that to the crude antigens, but the former reaction correlated well with a history of varicella and the presence or absence of virus-neutralizing antibodies.

Antigens, Viral↗
PubMed1980

Spread of varicella in hospitalized children having no direct contact with an indicator zoster case and its prevention by a live vaccine.

Varicella spread from a child with zoster to a total of 3 susceptible infants in another room in a children's ward, although they had been strictly isolated. To prevent spread of the disease, the staffs and patients were doing their own washing and no source of natural infection could be found. The cases indicate that it is difficult to predict nosocomial varicella infection or to prevent spread of the disease simply by isolation in a children's ward. A total of 11 other children without history of varicella in the ward were given live varicella vaccine before or immediately after this event. None of these children developed symptoms of varicella and all the susceptible children who were vaccinated showed an antibody response.

Adolescent↗
PubMed1977

Protection against varicella in family contacts by immediate inoculation with live varicella vaccine.

A live varicella vaccine (Oka strain) was given to susceptible household contacts of varicella to test the protective efficacy of the vaccination. Twenty-six contacts of 21 families were vaccinated, usually within three days after onset of the index cases. None of the vaccinated children developed clinical symptoms of varicella. Eighteen of 24 sera obtained before vaccination were found to be seronegative by complement fixation and neutralization tests. Seroconversion was observed in all of the 18. On the other hand, all of 19 unvaccinated contacts in the 15 families, who served as controls, showed typical manifestations of varicella from 10 to 33 days after onset of the index varicella cases. In three families, where only one sibling contact received vaccine and the other was an unvaccinated control, none of the vaccinated children showed any clinical symptoms while unvaccinated controls exhibited typical varicella symptoms 10 to 14 days after the onset of the index cases. These results indicate that varicella is prevented in household contacts by vaccination within three days following exposure.

Antibody Formation↗
PubMed1977

Protective efficacy of vaccination in children in four episodes of natural varicella and zoster in the ward.

It was previously reported that a live varicella vaccine (Oka strain) has been developed and that the immediate vaccination of hospitalized children was effective for prevention of spread of varicella in a ward. Six to nine months later, there were four separate episodes of varicella and zoster in the same ward. Eighteen children (11 with nephrotic syndrome, 6 with nephritis, and 1 with hepatitis) with no history of varicella were inoculated with a live vaccine before or immediately after admittance or occurence of the varicella and zoster cases. Twelve of them had been receiving steroid therapy and 15 of the 18 were found to be seronegative by complement fixation and neutralization tests before the vaccination. All of them became seropositive after vaccination without any clinical symptoms. The longest period between vaccination and exposure was nine months. None of the vaccinees exhibited varicella symptoms after exposure. Serological follow-up of ten vaccinated children was done, and booster responses were observed in some of them after exposure. These results suggest that the live vaccine affords immunity to the recipients. If hospitalized children are vaccinated before or immediately after exposure, isolation of the patient is unnecessary.

Adolescent↗
PubMed1976

Congenital renal arteriovenous fistula: case report, review of Japanese literature and description of non-radical treatment.

A case of congenital arteriovenous fistula diagnosed by measuring the oxygen saturation difference of renal veins at the time of selective renal angiographic examination and a review of 38 relevant Japanese cases are reported. The English as well as the Japanese literature was reviewed. Treatment has consisted of partial nephrectomy, ligation of the branch artery supplying the fistula and intentional embolization of the arterial branches, feeding the shunt by catheter.

Aged↗
PubMed1976

Linear straited vascular pattern: its implication on a renal angiogram clinical importance and pathologic verification.

A case of hypernephroma with neoplastic extension to the renal vein showing a characteristic linear striated vascular pattern on a renal angiogram is presented. A nephrectomy specimen was examined pathologically and angiographic correlation subsequently was inferred. Implication of this unusual pattern on the renal angiogram is emphasized through our experience and review of relevant literature in order to predict the prognosis and to prepare for radical treatment.

Adenocarcinoma↗
PubMed1975

Application of a live attenuated varicella vaccine to hospitalized children and its protective effect on spread of varicella infection.

Twenty-three hospitalized children with no history of varicella or no detectable complement fixing (CF) antibody, were vaccinated with a live attenuated varicella vaccine (Oka strain) immediately after the occurrence of a case of varicella in a children's ward of hospital. These children suffered from the nephrotic syndrome, nephritis, purulent meningitis, hepatitis etc., and 12 of them were receiving steroid therapy. An antibody response was noticed in all the vaccinated children, with mild fever in 6 and a mild rash in 2 of 6. It was uncertain whether these reactions were due to vaccinatin or to naturally acquired infection modified by vaccination. No other clinical reactions or abnormalities of the blood or urine were detected. Thus the spread of varicella infection was prevented, with the exception of one severe case in an unvaccinated patient. In another trial, 16 children with renal diseases were also vaccinated. All the children showed an immune response with no clinical reactions and no abnormalities in blood and urine examinations. Thus live varicella vaccine (Oka strain) can be used safely and effectively for hospitalized children, and its effectiveness in preventing spread of varicella infection was confirmed.

Animals↗