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T Kunitake

Publications and source records attributed to T Kunitake.

At least 55 records · Page 3Linked to original sources
PubMed1995

Parent-to-child transmission is relatively common in the spread of the human polyomavirus JC virus.

JC polyomavirus (JCV), the causative agent of progressive multifocal leukoencephalopathy, is ubiquitous in the human population, infecting children asymptomatically and then persisting in renal tissue. In most adults, renal JCV replicates and the progeny are excreted in urine. We used this urinary JCV to elucidate the routes of JCV transmission. A 610-bp JCV DNA region (IG region) encompassing the 3'-terminal sequences of both T-antigen and VP1 (major capsid protein) genes was amplified by means of PCR from urine specimens collected from all members of seven families. JCV strains were then unequivocally identified by the nucleotide sequences of the amplified IG regions. We could identify 18 distinctive JCV strains from 27 individuals. Different JCV strains were detected from all unrelated persons. However, the same viral strain was detected from one (four families), two (one family), or three offspring (one family) as well as from the fathers (three families) or from the mothers (three families). In total, the JCV strains detected in half of the JCV-positive children were identified in their parents. Since most humans are infected during childhood, these findings indicated that JCV is transmitted frequently from parents to children. We roughly estimated that 50% of JCV transmission occurs by this route and that the other 50% occurs outside the family.

Adult↗
PubMed1995

Inhibition of nitric oxide synthase attenuates osmotic thirst in the rat.

Changes in water intake after intraperitoneal injection of a nitric oxide synthase (NOS) inhibitor was studied in the rat. Administration of NW-nitro-L arginine methyl ester (L-NAME) at a dose of 50 mg/kg attenuated osmotic thirst induced by intraperitoneal injection of hypertonic saline, but did not affect spontaneous intake of water and thirst induced by subcutaneous injection of angiotension II. Pretreatment with L-arginine significantly attenuated the inhibition of osmotic thirst evoked with subsequent L-NAME. Administration of NW-nitro-D-arginine methyl ester (D-NAME) altered neither the spontaneous nor the osmotic drinking behavior. These findings suggest that NO may affect the osmotically induced drinking.

Angiotensin II↗
PubMed1994

Effects of centrally administered endothelin-3 on renal sympathetic nerve activity and renal blood flow in conscious rats.

Effects of intracerebroventricular (i.c.v.) administration of endothelin-3 (ET-3) on renal sympathetic nerve activity (RSNA) and renal blood flow (RBF), arterial blood pressure and heart rate were examined in conscious rats. Administration of ET-3 (1-50 pmol) through a chronically implanted cannula evoked an increase in arterial blood pressure and decreases in heart rate and RSNA, whereas RBF measured by Doppler flow probes did not change. Maximum changes in these responses occurred 10-15 min after i.c.v. administration of ET-3 and the responses returned to the control level after approximately 60 min. In sinoaortic denervated (SAD) rats, the decrease in RSNA induced by i.c.v. ET-3 was attenuated but still significantly persistent. During the experiments, we found that the injection of ET-3 (50-100 pmol) induced a barrel rotation, with an onset latency of 10-15 min. In those cases, prominent increases in arterial blood pressure and RSNA were observed, and these lasted for more than 60 min. The result shows that ET-3 can have centrally mediated effects on autonomic nerve activity as well as on cardiovascular function.

Animals↗
PubMed1994

Effect of immunosuppression on the urinary excretion of BK and JC polyomaviruses in renal allograft recipients.

Sixty-five renal allograft recipients on immunosuppressive therapy were examined for BK and JC viruria using Southern blot hybridization. The incidence and degree of BK and JC viruria were compared between this population (group RTR) and, an age- and sex-matched population of non-immunosuppressed individuals (group CTR). In the results, the incidence of BK viruria was significantly increased in the RTR group compared with the CTR group, while that of JC viruria was similar in the 2 groups. The proportion with a high level of JC viruria, however, was greater in the RTR group compared with the CTR group. Additionally, it was also demonstrated that the incidence of both BK and JC viruria was not affected by the characteristics of renal transplant recipients, such as differences in the donor source (living-related vs cadaveric), type of immunosuppressive agents used, or the time post-transplantation.

Adolescent↗
PubMed1994

Transmission of the human polyomavirus JC virus occurs both within the family and outside the family.

JC polyomavirus (JCV) is a ubiquitous symbiote in the human population, infecting children asymptomatically and then persisting in renal tissue. We reevaluated the urinary excretion of JCV in subjects in various age groups using PCR. The detection rate for urinary JCV DNA was 9 to 17% until the age of 20 years; this rate increased dramatically to about 46% at the ages of 20 to 29 years and then increased gradually with age. Therefore, it appears that in most people excretion of JCV begins at the age of 20 to 29 years, which is earlier than suggested previously. Next, we studied the way in which JCV is spread in the human population. We selected eight Japanese families in which both parents and children excreted JCV in their urine. Their JCV subtypes were determined by PCR amplification of a JCV DNA fragment; this was followed by restriction enzyme analysis. JCV species in all JCV-positive family members were classified into either of the two subtypes, subtypes CY and MY, which are prevalent in the Japanese population. The following features of JCV subtype distribution were seen in the families: (i) both subtypes were detected in children of five of the eight families, and (ii) of 21 children who excreted JCV, 14 children excreted the same subtypes excreted by their mothers or fathers, while the remainder (7 children) excreted subtypes different from those excreted by their parents. These features suggest that JCV is transmitted both within the family and outside the family. The data also indicate that vertical transmission is not common in the spread of JCV.

Adolescent↗
PubMed1993

[XX male].

Explore the source record for details and available documents.

Humans↗
PubMed1992

Power spectrum analysis of heart rate fluctuations and respiratory movements associated with cooling the human skin.

A length of respiratory movement and instantaneous heart rate was divided into 32 segments to adopt computerized power spectrum analysis. An array of frequency spectrum across all the segments was then constructed to demonstrate sequential changes in the respiratory rhythm (0.4 Hz), low (less than 0.1 Hz) and high (0.2-0.4 Hz)-frequency components of heart rate fluctuations associated with lowering the skin temperature. A significant increase in the power for the low and high frequency components of heart rate fluctuations accompanying bradycardia occurred by cooling the face to 0 and 10 degrees C, while cooling the foot to 0 degrees C yielded a significant increase and decrease in the power for the former and latter component, respectively, without change in heart rate. The spectral power for respiratory movements was not altered by these stimuli. The maximal change in the power for low- and high-frequency components as well as in the heart rate during cooling the face and foot to 0 degrees C was found to correlate negatively with the relative resting magnitude of the respective parameter in the pre-stimulus period. Similar relationship existed only with the power for low-frequency component of heart rate fluctuations when lowering the temperature of foot to 10 degrees C. The power spectrum array employed in this study thus enabled us to estimate the effectiveness of skin cooling on the three hemodynamic parameters.

Adult↗
PubMed1992

[Renal lymphoma. Report of 2 cases and review of the literature].

Two cases of renal lymphoma were reported. Case 1 was a 73-year-old, and case 2 was a 59-year-old female. Their chief complaint was flank pain. The findings obtained by CT and angiography were not compatible with renal cancer. The tentative diagnosis of case 1 was inflammatory disease or soft tissue tumor, and that of case 2 was renal subcapsular tumor. Histological specimen was obtained by open biopsy from case 1, and by nephrectomy from case 2. Immunohistochemical surface marker study revealed both tumors were B cell lymphoma. Chemotherapy (CHOP-Bleo, or PPA) in both cases and additional radiotherapy in case 2 markedly reduced the tumor size. Nevertheless, case 1 died 5 months later from recurrence, and case 2 died 14 months later of gastrointestinal bleeding. At autopsy, the renal subcapsular layer was infiltrated by lymphoma cells in both cases, and lymphadenopathy was not observed. Reviewing 16 cases previously reported as renal lymphoma, the capsular or subcapsular diffuse infiltration to the kidney is considered to be a characteristic feature of renal lymphoma.

Aged↗
PubMed1992

[Multifactorial analysis of the pyuria after transurethral prostatectomy].

Multifactorial analysis on 395 patients revealed important factors which prolong the pyuria after transurethral prostatectomy. They were the age of the patient, anemia and leukocytosis before surgery. These are factors which relate with the defense mechanism of the patient. Local factors, such as the duration of indwelling urethral catheter, the size of the prostate or prostatic bed and preoperative infection, were not so important for prolonging the pyuria after transurethral prostatectomy. The time of the resection and weight of the prostate had an intimate relation each other, and the former was the more important factor. The use of antimicrobials probably controlled these local risk factors, thus making them unimportant in the prolongation of the pyuria after transurethral prostatectomy.

Age Factors↗
PubMed1990

Synthetic cationic amphiphiles for liposome-mediated DNA transfection.

The compounds with efficient DNA transfection ability into eukaryotic cells were searched from various synthetic amphiphiles which have cationic heads and long saturated hydrocarbon tails. The efficiency of amphiphiles in gene transfer was examined by the transient expression of cytochrome b5 from its cDNA in COS cells. Among various synthetic amphiphiles, including N-[1-(2,3-dioleyloxy)propyl]-N,N,N-trimethylammonium chloride which is commercially available lipid, O,O'-didodecyl-N-[p-(2-trimethylammonioethyloxy)benzoyl]-(L) -glutamate bromide was highest in efficiency. The optimum condition for the amount of the amphiphile and DNA, and the incubation time were established to be 7.5-15 micrograms/22 mm dish and 1-10 micrograms/22 mm dish, and 48-72 h, respectively.

Animals↗
PubMed1990

[Long-term splinting of a traumatic upper permanent incisor with root fracture: report of a case].

Splinting was administered in a case of a traumatic upper right permanent incisor with root fracture. The patient was a boy, 11 years and 10 months old. The radiographical examination indicated that the injured tooth, that had already completed the apical growth, fractured horizontally at the middle 1/3 part of root. Clinical findings showed severe mobility of the coronal fragment of the injured tooth and a small amount of bleeding from the gingival sulcus, but there was almost no disposition of the coronal fragment and it was found to be vital in the electric pulp test. Immobilizing the coronal fragment of the injured tooth with the resin splint bonded directly to the tooth surfaces was prescribed. After 31 months, the pulp of the injured tooth remained vital, and after the elimination of the line of fracture and no symptoms of ankylosis were radiographically confirmed, the splint was then removed. From the case reported above the following implications were obtained: Although the previous investigators reported that the term of splinting teeth with root fractures was for 2-3 months, and prognosis of the injured teeth with root fractures having severe mobility of the coronal segments might be unfavorable, it was also indicated that the healing process by calcification might be possible with the use of long term splinting, as the pulp remained vital. In this case, it was found that the repair by calcification appeared initially on the proximate portion of the pulp at the fractured line, and slowly proceeded into the direction of the site of the outer surface of the root along the fractured line.

Child↗
PubMed1989

The ability of gustatory stimuli to modify the cardiac sympathetic and vagus nerve activities.

The effects of chemical stimulation of the oro-lingual mucosa on the heart rate and arterial blood pressure were studied together with changes in the cardiac nerve activities in the rat. Of four qualities of basic taste stimuli, only HCl and NaCl but not quinine and sucrose were effective in increasing the heart rate and blood pressure. These changes in the cardiovascular system were associated with an increase in the efferent cardiac sympathetic activity and a decrease in the vagal activity, although they were no longer appreciable after transection of the glossopharyngeal nerve.

Adrenergic Fibers↗
PubMed1988

Homogeneous immunoassay based on dihexadecyl-dimethylammonium bilayer membranes.

We describe a rapid, highly sensitive, simple immunoassay based on cationic bilayer membranes prepared from dihexadecyl-dimethylammonium bromide. This detergent was dispersed in water to give a slightly turbid solution which contained lamellar (not vesicular) bilayer membranes with a gel to liquid crystal phase transition (Tc, 28 degrees C). An anionic hapten (N,N'-bis(2,4-dinitrophenyl)-L-lysine) combined electrostatically with this cationic membrane to induce aggregation of membranes, making the solution turbid. This aggregation was suppressed by antibodies to the hapten. The aggregation rate was rapid at a temperature above Tc, and the amount of antibodies was quantified by measuring absorbance or light scattering of the aqueous solution with a detection limit of 0.1 ng/ml of the antibodies. Anionic and zwitterionic bilayer membranes from di(tetradecyl)phosphate and phosphocholine derivatives, respectively, were less sensitive as detectors of the hapten-antibody reaction. Ionic interactions between cationic bilayer membranes and anionic haptens are important for successful assay performance.

Agglutination↗