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Biomedical subjects

K Katagiri

Publications and source records attributed to K Katagiri.

At least 37 records · Page 2Linked to original sources
PubMed2000

1Alpha-hydroxyvitamin D3 prevents the decrease of bone mineral density in lactating beagles.

We assessed the change of bone mineral density (BMD) in lactating beagles with dual energy X-ray absorptiometry (DXA) and the preventive effect of 1alpha-hydroxyvitamin D3 (1alpha(OH)D3) on the BMD. Beagles, two to five years old, were used for detecting the time course change of BMD. Since the coefficient of variation (CV(%)) on detecting lumber vertebral (L2-L4) and tibial BMD by DXA was about 0.5%, DXA was useful to detect the change of BMD in beagles. There was a marked decrease in vertebral BMD during lactational period in the control group. The BMD levels after weaning were found to reverse to the initial level at mating. The same tendency was observed in tibial BMD as vertebral BMD, though the BMD changes were not marked. Beagles were administered at a dose of 0.1 microg/kg of 1alpha(OH)D3 three times in a week, and it was found to suppress the decrease in vertebral BMD during the breast feeding period. Also, the administration of 1alpha(OH)D3 promoted the prevention of decreased BMD during lactation both in vertebrae and tibiae. Significant effects of 1alpha(OH)D3 administration on tibial BMD were not observed. No adverse effects, such as hypercalcemia and hypercalciuria, were observed during the experimental period. Therefore, DXA was useful for detecting the changes of BMD in lactating beagles and the change of BMD was marked in lumber vertebrae, which are rich in trabecular bone. The preventive effect of 1alpha(OH)D3 on the decrease of BMD during the lactation period was observed in beagles.

Absorptiometry, Photon↗
PubMed2000

Locoregional cellular immunotherapy for patients with advanced esophageal cancer.

The objectives of the present study were to determine the safety of locoregional administration of autologous lymphocytes stimulated with autologous tumor cells and interleukin (IL) 2 in vitro and to find laboratory markers to predict either clinical toxicity or clinical response. Eleven patients with advanced (n = 4) or recurrent (n = 7) esophageal cancers received the locoregional administration of these activated lymphocytes every 2 weeks for two to nine times (mean, 5.6 times), and mean numbers of the administered cells were 0.8 x 10(9) cells per treatment. The activated lymphocytes that were pretested for their surface markers and CTL activity were endoscopically injected into primary tumor sites (n = 4) or directly injected into metastatic lymph nodes (n = 2), pleural (n = 4) or ascitic (n = 1) regions. Grade 3 hypotension, grade 2 diarrhea, and grade 1 fever were observed in 1, 1, and 6 patients, respectively, and there was no adverse effect in the remaining three patients. The clinical outcome was as follows: one, complete response (CR); three, partial response (PR); two, stable response (SR); and five, progressive disease (PD). CTL activity in the administered cells was observed in 5 of the 11 patients (1 CR, 3 PR, and 1 PD) and was not observed in the remaining 6 patients (2 SR and 4 PD). Percentages of CD16+ cells in the peripheral blood of the responder group (CR+PR) significantly increased when compared with those before treatment or with those of the nonresponder group before as well as after treatment. Because the clinical toxicity was moderate and tolerable, this new method of locoregional immunotherapy will be applicable for use in treatment of patients with advanced and recurrent esophageal cancers. Both CTL activity in the administered cells and the percentages of CD16+ cells in the peripheral blood may be useful laboratory markers for predicting of clinical response.

Aged↗
PubMed1999

Laminin 5 promotes activation and apoptosis of the T cells expressing alpha3beta1 integrin.

By introducing an alpha3 gene-containing plasmid into a human T cell line Jurkat, we prepared the T cells, which express a high level of the alpha3beta1 integrin, to assess the role of laminin 5 in the skin immune system. The alpha3beta1-expressing T cells adhered to laminin 5 and exhibited spreading. These adhered T cells showed a significant tyrosine phosphorylation of intracellular proteins including p59(fyn) upon T-cell receptor (TCR) stimulation. Six hours after cross-linking TCR, these cells on laminin 5 secreted a three times higher level of IL-2 than those on a BSA-coated plate. Twenty hours after the stimulation, 48% of the alpha3beta1-expressing T cells on laminin 5 caused apoptosis. The protein level of cyclin D3 and E decreased, while that of p53 increased in these T cells. These data suggest that laminin 5 may play at least two regulatory roles for T cell functions: augmentation of IL-2 production by antigen-stimulated T cells and induction of apoptosis in these T cells.

Apoptosis↗
PubMed1999

Ubiquitin-proteasome system is involved in induction of LFA-1/ICAM-1-dependent adhesion of HL-60 cells.

Membrane-permeable proteasome inhibitors, lactacystin (LC) and N-acetyl-Leu-Leu-norleucinal (ALLN), but not calpain inhibitor Z-Leu-leucinal (ZLL), prevented LFA-1/ICAM-1-dependent cellular adhesion of TPA-stimulated HL-60 cells. These proteasome inhibitors affected neither the induction of monocytic differentiation nor the accompanying protein-tyrosine phosphorylation. They suppressed the increase in the avidity of LFA-1 to ICAM-1 without changing the expression of these molecules. Immunoblotting using monoclonal antibody FK-1, which reacts specifically with polyubiquitinated proteins, demonstrated that the proteasome inhibitors caused the drastic accumulation of the polyubiquitinated proteins in the membrane fraction of TPA-treated HL-60 cells. This indicates that accompanying activation of LFA-1, TPA induces the polyubiquitination of the membrane proteins, which are rapidly degraded by proteasomes. These data taken together show that proteolysis mediated by the ubiquitin-proteasome system is a prerequisite for the induction of LFA-1-dependent adhesion of HL-60 cells.

Acetylcysteine↗
PubMed1999

Expression of Th1 and Th2 cytokine mRNAs in freshly isolated peripheral blood mononuclear cells of a patient with cutaneous paragonimiasis.

Using semiquantitative reverse transcriptase polymerase chain reaction, we examined the levels of various cytokine mRNAs of freshly isolated peripheral blood mononuclear cells (PBMCs) from a cutaneous paragonimiasis patient in the course of successful treatment with praziquantel administration. The pre-treatment levels of Th2 cytokines such as interleukin (IL)-4, IL-5, IL-10 and IL-13 mRNAs in PBMCs of the patient were much higher than those of healthy controls. The levels of IL-4, IL-5 and IL-13 mRNAs slightly elevated on day 2 of the treatment and then declined to the control levels on day 25. The IL-10 mRNA level rapidly decreased after the chemotherapy. In contrast, the mRNA levels of interferon (IFN)-gamma, a Th1 cytokine, remained in the control levels during the course. Peripheral eosinophil counts and levels of total IgE and eosinophil cationic protein in the sera correlated well with the levels of these Th2 cytokine mRNAs. These results suggested the major role of Th2 cytokines in clinical manifestation of human helminthic infection.

Adult↗
PubMed1999

Increased levels in vivo of mRNAs for IL-8 and macrophage inflammatory protein-1 alpha (MIP-1 alpha), but not of RANTES mRNA in peripheral blood mononuclear cells of patients with atopic dermatitis (AD).

Chemokines play an important role in the selective movement of leucocytes into inflammatory areas and they also activate various cells in inflamed tissues. However, it is unclear which cells are the main sources of chemokines in actual inflammatory diseases, even though both mononuclear cells and non-inflammatory resident cells are able to produce chemokines in vitro and the former cells are also the main target of chemokines. To clarify the roles of chemokines that are produced by mononuclear cells in AD, we measured levels in vivo of mRNA for IL-8 and MIP-1 alpha, as well as the level of regulated upon activation normal T cell expressed and secreted (RANTES) mRNA in freshly isolated peripheral blood mononuclear cells from patients with AD. We compared the results with those from psoriatic patients, and patients without AD who were suffering from other cutaneous diseases and eosinophilia. Levels of mRNAs were determined by semiquantitative reverse transcriptase-polymerase chain reactions. Levels of IL-8 and MIP-1 alpha mRNA were elevated not only in atopic patients but also in non-atopic patients with inflammatory skin disease associated with eosinophilia, compared with levels in psoriatic patients and healthy controls. Levels of RANTES mRNA were similar in atopic patients but they were lower in the other two groups of patients when compared with levels in healthy controls. In atopic patients, the levels of both IL-8 and MIP-1 alpha mRNAs but not of RANTES mRNA decreased with improvements in symptom scores after therapy. These findings suggest that mononuclear cells are not only the target of chemokines but might also play an important role in the pathogenesis of AD by producing IL-8 and MIP-1 alpha.

Adolescent↗
PubMed1999

Heterogeneity in expression of cytokine mRNA in freshly isolated peripheral blood eosinophils of patients with cutaneous-disease-associated eosinophilia.

BACKGROUND: It is thought that there are subpopulations of eosinophils concerning cytokine production: some of them predominantly produce Th1 cytokines, while others produce Th2. METHODS: By semiquantitative RT-PCR, the in vivo levels of the cytokine mRNA were measured in freshly isolated eosinophils and peripheral blood mononuclear cells (PBMCs) of 19 patients with eosinophilia, including 6 with atopic dermatitis, 4 with drug eruption, 1 with chronic dermatitis, 2 with erythroderma, 3 with bullous pemphigoid, 1 each with urticaria, adult T cell lymphoma, and hypereosinophilic syndrome, and 7 healthy individuals. Eosinophils and PBMCs were isolated by centrifugation over Ficoll-Paque and magnetic cell separation using anti-CD16 antibody. RESULTS: The IL-4/IFN-gamma ratio in eosinophils as well as PBMCs was increased and correlated well with IgE levels in atopic dermatitis. In other cytokines, such as IL-8, TNF-alpha and TGF-beta1, the levels of mRNA expression were variable among each sample. CONCLUSION: Not only helper T lymphocytes but also eosinophils may take part in the pathogenesis of cutaneous diseases by virtue of heterogeneity of Th1 and Th2 cytokine production.

Adult↗
PubMed1998

Carcinoid of the esophagus located in lamina propria.

We report a carcinoid tumor in the mucosal layer of the esophagus of a 63-year-old man. Barium X-ray and endoscopy indicated the tumor to be a polypoid lesion in the lower esophagus. Endoscopic ultrasonography (EUS) demonstrated the lesion to be a sharply demarcated hyperechoic tumor in the mucosal layer. Biopsy yielded a diagnosis carcinoid of the esophagus. In the resected specimen of the esophagus, the tumor was 11 mm in longest dimension with a shallow depression on it smooth surface. Histologically, the tumor was located in the mucosal layer, as shown by EUS, and was composed of small round cells which were positive for argyrophil, but not argentaffine. Carcinoid tumor of the esophagus found at an early stage, and localized in the lamina propria layer, is very rare. The present case is the second report in Japan.

Carcinoid Tumor↗
PubMed1998

Growth stimulation of normal melanocytes and nevocellular nevus cells by gastrin releasing peptide (GRP).

In order to know the possible effects of gastrin releasing peptide (GRP) on nevus cells and melanocytes, we studied the effect of GRP on the proliferation of cultured human nevus cells and normal melanocytes. MTS assay showed that GRP stimulated the growth of viable melanocytes at 1000 ng/ml. GRP also stimulated the growth of nevus cells in a dose dependent manner and maximum stimulation was obtained at 100 ng/ml of GRP. GRP was less effective for growth stimulation of normal melanocytes than nevus cells. The cytoplasm of nevus cells were positively stained by polyclonal anti-GRP antibody. We also detected the expression of GRP and GRP receptor mRNAs in these cells by RT-PCR. These results suggest that GRP acts as an autocrine growth factor for nevus cells and normal melanocytes.

Cell Division↗
PubMed1998

[Clearance of gadolinium contrast agent by hemodialysis: in vitro and clinical studies].

In order to evaluate the safety and pharmacokinetics of gadolinium contrast agents in patients with hemodialysis, in vitro and clinical studies were performed. Gd-DTPA and Gd-HP-DO3A solutions were dialysed by standard methods. One classic type (cellulose acetate) and two high-performance types (PMMA and polyacrylonitrile) were used. Eleven dialysis patients underwent normal dose contrast MRI followed by usual dose hemodialysis (HD). PMMA dialysis membranes were used for 8 patients and cellulose acetate membranes for 3 patients. Serum levels of gadolinium, BUN and creatinine were analyzed before and after the 1st HD and after the 2nd, 3rd and 4th HD. Side effects and edema were carefully observed. In vitro studies showed that 11.1 hours of dialysis would be necessary to remove 97% of the injected dose of contrast agent by using a first-order kinetic model of dialysis time. When dialysis membranes and contrast agents were compared, statistically significant differences were noted between dialysis membranes and all contrast agents. In the clinical study, 79.1% of the contrast agent was dialyzed after the 1st dialysis and 99.6% after the 4th dialysis. These results showed that all contrast agents and both dialysis membranes were suitable. Neither changes in laboratory parameters nor side effects were observed. The present study suggests, consequently, there are no contraindications when using the ordinary dose of contrast agent even in patients with dialysis.

Aged↗
PubMed1997

Increased levels of IL-13 mRNA, but not IL-4 mRNA, are found in vivo in peripheral blood mononuclear cells (PBMC) of patients with atopic dermatitis (AD).

Previous studies using in vitro systems with various stimuli have shown that PBMC from patients with AD show increased levels of IL-4 but decreased levels of interferon-gamma (IFN-gamma) compared with PBMC from normal controls. However, in vitro conditions do not always mimic the in vivo condition. We therefore believe that it is important to quantify the expression of these cytokines in freshly isolated PBMC. This study examines the expression of IFN-gamma, IL-4 and IL- 13 mRNA in freshly isolated PBMC from adult patients with AD, from patients with psoriasis vulgaris and from healthy adults, using the semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) method. Levels of IFN-gamma mRNA were significantly lower in PBMC of patients with AD than in controls. IL-4 mRNA levels did not differ significantly between groups. Conversely, levels of mRNA for IL-13 were significantly greater in PBMC of patients with AD than in controls. An increase in IL-13 expression may regulate the in vivo synthesis of IgE in patients with AD.

Adolescent↗
PubMed1997

Dermatomyositis associated with primary intramuscular B cell lymphoma.

A rare case of dermatomyositis associated with primary intramuscular malignant lymphoma is described. A 40-year-old Japanese woman noticed swelling of the right thigh during the treatment of dermatomyositis with prednisolone, azathioprine and cyclophosphamide. A biopsy specimen taken from the right quadriceps muscle revealed infiltration of lymphoma cells which were positive for CD20. We reviewed 12 cases of dermatomyositis associated with malignant lymphoma reported in Japanese literature between 1984 and 1996.

Adult↗
PubMed1997

Perineural and neural involvement in skin cancers.

BACKGROUND: Malignant skin tumors rarely spread along nerves. Complete resection of involved nerves is often unsuccessful. OBJECTIVE: In the treatment of tumors with perineural invasion, surgeons should accurately estimate the extent of distant spread. METHODS: We report six cases of skin cancers, including two basal cell carcinomas, two squamous cell carcinomas, and two neurotropic malignant melanomas, that invaded nerve or perineural spaces. RESULTS: In three of the cases, the tumors developed on the face and involved the infraorbital nerves or its branches. Two patients suffered from tumors on old burn scars of lower legs. Branches of posttibal nerves were involved in both cases. In the last case, tumor invasion of a branch of the greater occipital nerve was detected. CONCLUSION: The extent of surgical excision should include the area of skin supplied by the affected nerve, which must be resected in continuity.

Adult↗
PubMed1997

Age-related effects of heat stress on protective enzymes for peroxides and microsomal monooxygenase in rat liver.

To evaluate the age-related response of essential cell functions against peroxidative damage in hyperthermia, we studied the biochemical response to heat stress in both young and aged rats. Passive hyperthermia was immediately observed in rats after exposure to hot environments. In aged rats, the rectal temperature maintained thermal homeostasis and increased to the same degree as in young rats. In these aged animals, the damage from heat stress was more serious than in young animals. In aged rats under normal environmental conditions, hepatic cytosolic glutathione peroxidase (GSH peroxidase) activities were markedly higher than those activities in younger rats. Hepatic cytosolic GSH peroxidase activities were induced by heat stress in young rats but were decreased by hot environments in aged rats. Hepatic catalase activities in young rats were not affected by hot environments, whereas in aged rats, hepatic catalase activities were seriously decreased. Catalase activities in the kidney of aged rats were also reduced by hot environments. Lipid peroxidation in the liver was markedly induced in both young and aged rats. Because the protective enzymes for oxygen radicals in aged rats were decreased by hot environments, lipid peroxidation in the liver was highly induced. In aged rats, lipid peroxidation in intracellular structures such as mitochondria and microsomes was also markedly induced by hot environments. In both young and aged rats, hyperthermia greatly increased the development of hypertrophy and vacuolated degeneration in hepatic cells. In aged rats, both mitochondria and endoplasmic reticulum of the hepatic cells showed serious distortion in shape as a result of exposures to hot environments. Microsomal electron transport systems, such as cytochrome P450 monooxygenase activities, were seriously decreased by heat stress in aged rats but not in young rats. Although the mitochondrial electron transport systems were not affected by acute heat stress in young rats, their activities were simultaneously inhibited after long-lasting heat exposure. In isolated hepatic cells and polymorphonuclear leukocytes in animals, the 70-kDa heat shock-induced proteins were markedly increased by heat stress. In conclusion, the heat stress-inducible oxygen radical damage becomes more severe according to the age of rats. Because aging and hyperthermia have a synergistic effect on lipid peroxidation, protective enzyme activities for oxygen radicals may be essential for surviving and recovering from thermal injury in aged animals and also in humans.

Aging↗
PubMed1997

A constitutive modeling of the human lumbar intervertebral disc and forward-backward bending simulation.

This paper presents a constitutive law of the lumbar intervertebral disc to be described mathematically with the finite deformation theory. Mechanical behavior of the cadaveric lumbar disc obtained from continuous cyclic compression-tension tests and continuous cyclic axial torsion tests was formulated by the constitutive equation with a semi-circular shaped model. These equations were formulated with or without taking the nucleus pulposus into account. It was also confirmed that forward-backward bending behavior of the disc could be simulated numerically from these equations.

Biomechanical Phenomena↗
PubMed1997

In vivo expression of IL-4, IL-5, IL-13 and IFN-gamma mRNAs in peripheral blood mononuclear cells and effect of cyclosporin A in a patient with Kimura's disease.

Semiquantitative reverse transcription-polymerase chain reaction was used to analyse the expression of cytokine mRNAs in freshly isolated peripheral blood mononuclear cells obtained from a patient with Kimura's disease. The patient was treated with cyclosporin A (CsA) after incomplete tumour resection and irradiation of lesions. Levels of interleukin (IL)-4, IL-5 and IL-13 mRNA were elevated and the level of interferon (IFN)-gamma mRNA was within normal limits before treatment. The levels of IL-4, IL-5 and IL-13 mRNA, the number of eosinophils, and the serum level of IgE decreased markedly after surgery and radiation therapy. CsA treatment suppressed these values in a dose-dependent manner, but had a minimal effect on the level of IFN-gamma mRNA. The number of peripheral eosinophils decreased in association with decreases in the levels of IL-4, IL-5 and IL-13 mRNAs during CsA therapy; the serum level of IgE remained low during therapy and did not fluctuate in association with changes in cytokine levels. These results suggest the Th2 cytokines play a part in the development of Kimura's disease and that CsA suppresses the activity of this disease.

Aged↗