Search PubMed⌕ Search

Biomedical subjects

H Kanazawa

Publications and source records attributed to H Kanazawa.

350 records · Page 20Linked to original sources
PubMedDate not supplied

Optimal administration schedules of the newly synthesized platinum analog NK121 and bleomycin analog NK313 in nude mice with squamous cell carcinoma.

To determine the optimal administration schedules of the newly synthesized, less nephrotoxic platinum analog NK121 and less pneumotoxic bleomycin analog NK313, the antitumor effects of 2 different injection schedules, (1) single injections on days 1, 5, and 9, (2) continuous infusion for 7 days, were compared in nude mice bearing human squamous cell carcinoma. Tumor growth delay was employed as the experimental endpoint of antitumor activity. Body weight and hematologic changes in the mice were also investigated as indications of drug toxicity after the combination treatment of NK121 and NK313. The antitumor effects of the 2 analogs indicated higher responses with the single injections of NK121 and continuous infusion of NK313. In combination chemotherapy with NK121 and NK313, the highest antitumor effect was observed when mice were given NK121 by single injections followed by NK313 by continuous infusion. This sequence was also less toxic than a simultaneous treatment schedule, which was of weak clinical significance because of its low antitumor activity, severe weight loss, slight myelosuppression, and renal toxicity.

Animals↗
PubMedDate not supplied

A novel MR angiography technique: SPEED acquisition using half-Fourier RARE.

A novel MR angiography (MRA) method, swap phase encode extended data (SPEED), was developed. Two one-shot images with the phase-encode directions swapped were collected within a single breath-hold period and processed with a maximum intensity projection (MIP) to obtain an image. In this study, a long echo train two-dimensional rapid acquisition with relaxation enhancement (RARE) sequence with half-Fourier (half-RARE) was used to obtain the pulmonary MRA images. The MIP image obtained using the SPEED technique presented promising results for pulmonary vessels.

Fourier Analysis↗
PubMedDate not supplied

Transjugular intrahepatic portosystemic shunt in a patient with cavernomatous portal vein occlusion.

A 23-year-old woman with liver cirrhosis secondary to primary sclerosing cholangitis was referred to us for the treatment of recurrent bleeding from esophageal varices that had been refractory to endoscopic sclerotherapy. Her portal vein was occluded, associated with cavernous transformation. A transjugular intrahepatic portosystemic shunt (TIPS) was performed after a preprocedural three-dimensional computed tomographic angiography evaluation to determine feasibility. The portal vein system was recanalized and portal blood flow increased markedly after TIPS. Esophageal varices disappeared 3 weeks after TIPS. Re-bleeding and hepatic encephalopathy were absent for 3 years after the procedure. We conclude that with adequate preprocedural evaluation, TIPS can be performed safely even in patients with portal vein occlusion associated with cavernous transformation.

Adult↗
PubMedDate not supplied

Calcitonin gene-related peptide antagonizes the protective effect of adrenomedullin on histamine-induced bronchoconstriction.

1. In the present study the possible relationship between adrenomedullin (AM) and calcitonin gene-related peptide (CGRP) in the regulation of airway functions in anaesthetized guinea-pigs was examined in vivo. 2. We found that AM significantly inhibited histamine-induced bronchoconstriction in a dose-dependent manner. CGRP or the CGRP receptor antagonist (CGRP [8-37]) alone did not affect pulmonary resistance and pretreatment with CGRP or CGRP [8-37] did not significantly affect histamine-induced bronchoconstriction. However, AM-induced bronchoprotection was significantly inhibited by pretreatment with CGRP or CGRP [8-37] in a dose-dependent manner. 3. It is therefore possible that CGRP may be competitive, at least in part, with binding sites of AM in the guinea-pig airway. Exogenous AM may be useful for the management of bronchial asthma, not only as a potent bronchodilator, but also as a functional antagonist of CGRP.

Adrenomedullin↗
PubMedDate not supplied

Topographical relation between serotonin-containing paraneurons and peptidergic neurons in the intestine and urethra.

Luminal stimulation of enterochromaffin (EC) cells is known to cause their release of serotonin which in turn may induce a variety of reflexes via mucosal intrinsic neurons. To morphologically support this idea, the present study demonstrates a close topographical relationship between EC cells and nerves, using whole-mount preparations. Beaded nerve fibers containing vasoactive intestinal polypeptide (VIP) were observed in close proximity to serotonin-immunoreactive EC cells in the small and large intestines of the rat and guinea pig; in whole-mount preparations, the VIP nerve fibers appeared to underlie EC cells. This finding correlates with the physiological datum that the intra-arterial infusion of serotonin causes VIP release from the intestine. Canine urethral serotonin cells, a counterpart of the intestinal EC cells, were shown to contact intraepithelial nerves immunoreactive for calcitonin gene-related peptide. The neuroparaneuronal connection in the urethra may play an important role in the serotonin-evoked urethrogenital reflex. Intestinal and urethral serotonin-containing paraneurons, which are sensory in nature, may release serotonin in response to luminal stimuli, and directly activate adjacent peptidergic neurons to initiate the reflex arcs.

Animals↗
PubMedDate not supplied

Arginine vasopressin increases perinuclear [Ca2+] in single cultured vascular smooth muscle cells of rat aorta.

The effects of arginine vasopressin (AVP, 10(-7) M) on the spatial dynamics of intracellular [Ca2+] in single cultured smooth muscle cells of the rat aorta were studied by digital imaging microscopy using the fluorescent Ca2+ indicator fura-2. The nuclear and cytosolic regions were distinguished by the fluorescent image excited at 380 nm. Changes in intracellular [Ca2+] were expressed as percent increases in the ratios of fluorescence intensity at 500 nm excited by 340 and 380 nm. AVP increased the nuclear and cytosolic [Ca2+] in Ca(2+)-containing (control) (285 +/- 27 and 172 +/- 22%, respectively) or Ca(2+)-free (203 +/- 26 and 121 +/- 15%, respectively) solutions. However, caffeine (20 mM) and ryanodine (20 microM) greatly attenuated the [Ca2+] increase induced by AVP in both regions (61 +/- 21 and 42 +/- 15%, respectively). On the ratio image, the nuclear region was discriminated from other regions at the peak response to AVP in preparations treated with caffeine and ryanodine, whereas the outline of the nuclear region was indistinct in untreated preparations. The finding implies that caffeine- and ryanodine-responsive Ca2+ storage sites may exist in the region surrounding the nucleus. The results suggest that the region surrounding the nucleus may be one of the important Ca2+ storage sites with regard to the responses of rat aortic smooth muscle cells to AVP.

Animals↗
PubMedDate not supplied

Correlation between clinical features and deletions of the gene for dystrophin in Duchenne muscular dystrophy.

The clinical course and prognosis of Duchenne muscular dystrophy (DMD) was compared in patients with deletions of the gene for dystrophin (cDMD) and those without such deletions. A total of 24 patients was followed for at least 2 yrs. At age 12 the rating of the activities of daily life (ADL) and disease stage were less favorable in those patients with deletions of the gene for cDMD. At age 14, no difference in ADL and disease stage was observed between the two groups. The percent vital capacity was lower in those patients with the cDMD deficit. When the prognosis was evaluated by multivariate analysis of the data obtained at age 12, the percent of patients predicted as dying before the age of 20 was 40% for those without the cDMD deficit but 76% for those who were cDMD defective. None of the cDMD defective patients lived longer than 20 yrs, whereas 5 of 14 patients without the cDND deficit survived longer than 20 yrs. Disorders such as cardiac and respiratory failure were also seen more frequently in the cDND defective patients. These results suggest that patients with Duchenne muscular dystrophy with defective cDMD have more severe disease than those without cDMD deficit.

Activities of Daily Living↗