Biomedical subjects

Mitsuhiro Nakajima

Publications and source records attributed to Mitsuhiro Nakajima.

10 recordsLinked to original sources

PubMed2006

Cell to cell contact through ICAM-1-LFA-1 and TNF-alpha synergistically contributes to GM-CSF and subsequent cytokine synthesis in DBA/2 mice induced by 1,3-beta-D-Glucan SCG.

SCG is a major 6-branched 1,3-beta-D-glucan in Sparassis crispa Fr. showing antitumor activity. We recently found that the splenocytes from naive DBA/1 and DBA/2 mice are potently induced by SCG to produce interferon- gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin-12p70 (IL-12p70), and that GM-CSF plays a key biologic role among these cytokines. In this study, we investigated the contribution of cell-cell contact and soluble factors to cytokine induction by SCG in DBA/2 mice. Cell-cell contact involving intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1) was an essential step for the induction of GM-CSF and IFN-gamma by SCG but not for the induction of TNF-alpha or IL-12p70 by SCG. SCG directly induced adherent splenocytes to produce TNF-alpha and IL-12p70. GM-CSF was required for the induction of TNF-alpha by SCG, and in turn, TNF-alpha enhanced the release of GM-CSF and thereby augmented the induction of IL-12p70 and IFN-gamma by SCG. Neutralization of IL-12 significantly inhibited the induction of IFN-gamma by SCG. We concluded that induction of GM-CSF production by SCG was mediated through ICAM-1 and LFA-1 interaction, GM-CSF subsequently contributed to further cytokine induction by SCG, and reciprocal actions of the cytokines were essential for enhancement of the overall response to SCG in DBA/2 mice.

Adjuvants, Immunologic↗

PubMed2006

Mechanism of enhanced hematopoietic response by soluble beta-glucan SCG in cyclophosphamide-treated mice.

SCG is a major 6-branched 1,3-beta-D-glucan in Sparassis crispa Fr. SCG shows antitumor activity and also enhances the hematopoietic response in cyclophosphamide (CY)-treated mice. In the present study, the molecular mechanism of the enhancement of the hematopoietic response was investigated. The levels of interferon-(IFN-)gamma, tumor necrosis factor-(TNF-)alpha, granulocyte-macrophage-colony stimulating factor (GM-CSF), interleukin-(IL-) 6 and IL-12p70 were significantly increased by SCG in CY-treated mice. GM-CSF production in the splenocytes from the CY-treated mice was higher than that in normal mice regardless of SCG stimulation. Neutralizing GM-CSF significantly inhibited the induction of IFN-gamma, TNF-alpha and IL-12p70 by SCG. The level of cytokine induction by SCG was regulated by the amount of endogenous GM-CSF produced in response to CY treatment in a dose-dependent manner. The expression of beta-glucan receptors, such as CR3 and dectin-1, was up-regulated by CY treatment. Blocking dectin-1 significantly inhibited the induction of TNF-alpha and IL-12p70 production by SCG. Taken together, these results suggest that the key factors in the cytokine induction in CY-treated mice were the enhanced levels of both endogenous GM-CSF production and dectin-1 expression.

Animals↗

PubMed2005

Efficacy of plasma exchange and methylprednisolone pulse therapy on influenza-associated encephalopathy.

Patients with a new type of influenza-associated encephalopathy with high mortality are increasing in Japan and the United States. We present three patients treated with methyprednisolone pulse treatment and plasma exchange to remove cytokines, and all three patients recovered without severe sequela. IL-6 decreased dramatically after the start of the plasma exchange and methyprednisolone. Therefore when influenza-associated encephalopathy is actually diagnosed, steroid pulse therapy should be started at an early stage, and when signs of DIC and/or MOF appear, plasma exchange is recommended to remove the cytokines and NOx.

Brain Diseases↗

PubMed2005

Soy isoflavone aglycone modulates a hematopoietic response in combination with soluble beta-glucan: SCG.

Soy isoflavone aglycones (IFAs) have a wide range of biological actions that suggest they may be of use in cancer prevention. On the other hand, a branched beta-glucan from Sparassis crispa (SCG) is a major 6-branched 1,3-beta-D-glucan in an edible/medicinal mushroom: Sparassis crispa showing antitumor activity. We have previously reported that both oral and intraperitoneal administration of SCG enhanced the hematopoietic response in cyclophosphamide (CY)-induced leukopenic mice. In this study, we investigated the hematopoietic response due to IFA in combination with SCG in CY-induced leukopenic mice. The oral administration of IFA in combination with SCG synergistically enhanced the number of white blood cells, and increased spleen weight. Analyzing the leukocyte population by flow cytometry, the combination of IFA and SCG increased the number of monocytes and granulocytes in the spleen. Taken together, the combination of IFA and SCG synergistically provides the hematopoietic responses that are enhanced over IFA or SCG alone.

Administration, Oral↗

PubMed2005

[Developmental changes in the Collis horizontal reaction analyzed using a three-dimensional video motion analysis system. I. Examination of techniques for inducing Collis horizontal reaction].

We used a three-dimensional video motion analysis system to evaluate techniques for inducing the Collis horizontal reaction in 46 infants (total 217 times) from 1-9 months old. Additionally, we examined the safety of different techniques for inducing the Collis horizontal reaction in 20 infants (total 66 times), from 1-3 months old, 40 times by holding the shoulder joint and 26 times by not holding the shoulder joint. Regardless of who performed the examination, the average height that induced the reaction increased from 24.3 to 34.6 cm and the average speed of reaction increased from 28.2 to 43.4 m/s as the age of the infants increased. Additionally, when the Collis horizontal reaction was induced in infants 1-3 months old by holding the shoulder joint of infants, the average fall angle of the head was 7.291 degrees and was not significantly larger than when the reaction was induced by not holding the shoulder joint, which resulted is an average fall angle of the head was 19.302 degrees. However, although the average speed to support the body increased, the fall angle of the head did not increase when the shoulder joint was held. The Collis horizontal reaction is usually not performed in early infancy before head control is acquired, because of the burden to neck caused by the fall of the head and the excess expansion of shoulder joint capsule. However these results suggest that when performing the Collis horizontal reaction in early infancy before head control is acquired, the Collis horizontal reaction can be safely performed by holding the shoulder joint, regardless of the skill of the diagnostician. Therefore, the Collis horizontal reaction is an excellent method to assess infant development, and can be performed at the usual infant health examinations.

Child Development↗

PubMed2005

[Developmental changes in the Collis horizontal reaction analyzed using a three-dimensional video motion analysis system. II. Examination of upper-limb movement during the Collis horizontal reaction].

At four months old, infants of 72% challenged with the Collis horizontal reaction touch the floor with the back of their free hand. As the infants grow older, the ratio of infants that open their free hand and perform a support reaction increases from 0% to 100%. At nine months old, all infants perform this support reaction with their free hand palm-side down. To assess infant development more accurately, we used a three-dimensional video motion analysis system to evaluate upper limb movement in 38 infants (total 151 times) from 4-9 months old during the second and third phases determined by the Collis horizontal reaction. By analyzing the constituent components of upper limb movement during the Collis horizontal reaction, we assessed the usefulness of the reactions as an objective tool to measure developmental changes in infants. During the analysis, we thought to assess the speed of the upper limb reaction was respect to pronating the forearm, supporting the body with the palm down, and location of their free hand. The analysis shows that if development progresses normally and infants pronate the forearm to support the body with the palm down, the central value at which their free hand is located moves to a point under the shoulder. The results suggest that in infants four to nine months old, the Collis horizontal reaction is an excellent method to assess not only the present physical development level, but also future physical development attainment by only evaluating developmental changes of upper limb movement only.

Child Development↗

PubMed2004

Granulocyte-macrophage colony-stimulating factor (GM-CSF) regulates cytokine induction by 1,3-beta-D-glucan SCG in DBA/2 mice in vitro.

Sparassis crispa Fr. is an edible/medicinal mushroom that recently became cultivable in Japan. SCG is a major 6-branched 1,3-beta-D-glucan in S. crispa showing antitumor activity. We recently found that the splenocytes from naive DBA/1 and DBA/2 mice strongly react with SCG to produce interferon-gamma (IFN-gamma). In this study, cytokines induced by SCG were screened and found to be IFN-gamma, tumor necrosis factor-alpha (TNF-alpha), granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin-12 (IL-12p70). The addition of recombinant murine GM-CSF (rMuGM-CSF) to spleen cell cultures from various strains of mice synergistically enhanced IFN-gamma, TNF-alpha and IL-12p70 in the presence of SCG. In contrast, neutralizing GM-CSF using anti-GM-CSF monoclonal antibody (mAb) significantly inhibited IFN-gamma, TNF-alpha, and IL-12p70 elicited by SCG. We conclude that GM-CSF is a key molecule for cytokine induction by beta-glucan, and GM-CSF induction by SCG is the specific step in DBA/2 mice in vitro.

Animals↗

PubMed2003

Antibody to soluble 1,3/1,6-beta-D-glucan, SCG in sera of naive DBA/2 mice.

A branched beta-glucan from Sparassis crispa (SCG) is a major 6-branched 1,3-beta-D-glucan showing antitumor activity. In the present study, we examined the anti-SCG antibody in naive mice by ELISA. Using SCG coated plate, sera of naive DBA/1 and DBA/2 mice contained significantly higher titers of antibody than other strains of mice. Anti-SCG Ab titers of each DBA/1 and DBA/2 mice were significantly varied. Using various polysaccharide-coated plate, sera of DBA/2 mice also reacted with a beta-glucan from Candida spp. (CSBG) having 1,3-beta and 1,6-beta-glucosidic linkages. The SCG specific immunoglobulin (Ig) M but G was detected in sera. The reactivity of sera to coated SCG was neutralized by adding soluble SCG and CSBG as competitor. These results suggested that DBA/1 and DBA/2 strains carry specific and unique immunological characteristics to branched 1,3-/1,6-beta-glucan.

Agaricales↗

PubMed2002

IFN-gamma induction by SCG, 1,3-beta-D-glucan from Sparassis crispa, in DBA/2 mice in vitro.

Sparassis crispa Fr. in an edible mushroom recently cultivable in Japan. A branched beta-glucan from S. crispa (SCG) is a major 6-branched 1,3-beta-D-glucan showing antitumor activity. In this study, we examined interferon-gamma (IFN-gamma) induction by SCG from splenocytes in DBA/2 mice in vitro. In the splenocytes derived from almost all inbred strains of mice except for DBA/1 and DBA/2 mice, IFN-gamma production was not induced by SCG. The breeder and genders of DBA/2 mice showed no influence on IFN-gamma induction by SCG. On the other hand, the magnitude of IFN-gamma induction was lower in young mice than in their older counterparts. IFN-gamma was induced by SCG in adherent splenocytes, but IFN-gamma production was most significantly increased by SCG in instances involving coexistence of adherent and nonadherent splenocytes. In fact, inhibition of cell-cell contact reduced IFN-gamma induction by SCG. In addition, interleukin-12 p70 (IL-12p70) was induced by SCG in DBA/2 mice. It was suggested that soluble factors and cell-cell contact mediate synergistic effects on SCG-induced IFN-gamma production.

Agaricales↗

PubMed2002

Effect of SCG, 1,3-beta-D-glucan from Sparassis crispa on the hematopoietic response in cyclophosphamide induced leukopenic mice.

Sparassis crispa Fr. is an edible mushroom recently cultivable in Japan. It contains a remarkably high content of 6-branched 1,3-beta-D-glucan showing antitumor activity. Using ion-exchange chromatography, a purified beta-glucan preparation, SCG, was prepared. In this study, we examined the hematopoietic response by SCG in cyclophosphamide (CY)-induced leukopenic mice. SCG enhanced the hematopoietic response in CY induced leukopenic mice by intraperitoneal routes over a wide range of concentrations. SCG enhanced the hematopoietic response in CY-treated mice by prior or post administration. Analyzing the leukocyte population by flow cytometry, monocytes and granulocytes in the peritoneal cavity, liver, spleen and bone marrow (BM) recovered faster than in the control group. The ratio of natural killer cells and gammadelta T cells in the liver, spleen and peritoneal cavity was also increased. In contrast, CD4+ CD8+ cells in the thymus were temporarily significantly decreased by the administration of SCG. Interleukin-6 (IL-6) production of CY+SCG-treated peritoneal exdated cells (PECs), spleen cells and bone marrow cells (BMCs) were higher than that of the CY-treated group. By in vitro culture of CY-treated PEC and spleen cells, IL-6 production was enhanced by the addition of SCG. These facts suggested the possibility that IL-6 might be a key cytokine for the enhanced hematopoietic response by SCG.

Animals↗