Search PubMed⌕ Search

Biomedical subjects

H Morikawa

Publications and source records attributed to H Morikawa.

At least 91 records · Page 5Linked to original sources

Interleukin 4 (IL-4) blocks the IL-2-induced increased in natural killer activity and DNA synthesis of decidual CD16-CD56bright NK cells by inhibiting expression of the IL-2 receptor alpha, beta, and gamma.

The natural killer (NK) activity and DNA synthesis of decidual CD16-CD56bright NK cells were markedly elevated by treatment with interleukin 2 (IL-2). IL-4 did not affect NK activity or DNA synthesis of decidual CD16-CD56bright NK cells, but inhibited the IL-2-induced NK activity and DNA synthesis in a dose-dependent manner. Flow cytometry of decidual mononuclear cells cultured in IL-2 or IL-4 or both IL-2 and IL-4 demonstrated IL-4 inhibition of the expression of the IL-2 receptor alpha (IL-2R alpha), IL-2R beta, and IL-2R gamma on decidual CD16-CD56bright NK cells. This suggests that IL-4 blocks the IL-2-induced NK activity and DNA synthesis of decidual CD16-CD56bright NK cells by inhibiting the expression of IL-2R alpha, IL-2R beta, and IL-2R gamma.

CD56 Antigen↗

Expression of the interleukin-2 receptor gamma chain on cord blood mononuclear cells.

Lymphocytes in umbilical cord blood and neonatal peripheral blood have been shown to have less ability in an immune reaction. In our present experimental approach to address this issue, we made use of the cord blood of full-term birth infants to investigate the expression of the interleukin- 2 receptor gamma (IL-2Rgamma) chain that is shared with receptors for IL-4, IL-7, IL-9, and IL-15 as well as IL-2. The gamma chain expression in cord blood lymphocytes was about one-third that in the lymphocytes of adults, whereas no significant difference between cord blood and adult monocytes was observed. A reduced expression of the gamma chain was observed in all of the CD4+ T cells, CD8+ T cells, gamma-delta T cells, B cells, CD16+ natural killer (NK) cells, and CD56(bright) NK cells of the cord blood lymphocytes. The reduced gamma chain expression reached two-thirds of that in adults after 3 days of culture in vitro and in infants 3 days after birth, thus implying that the increase in the gamma chain may significantly contribute to the prevention of neonatal infection.

Adult↗

Inositol trisphosphate/Ca2+ as messengers of bradykinin B2 and muscarinic acetylcholine m1-m4 receptors in neuroblastoma-derived hybrid cells.

Neuroblastoma x glioma hybrid NG 108-15 and neuroblastoma x fibroblast hybrid NL308 cells possess endogenous bradykinin B2 receptors and m4 muscarinic acetylcholine receptors (mAChRs), which couple to phospholipase C and adenylate cyclase, respectively. Four genetic subtypes of mAChRs differed in their effects when stimulated in NG108-15 and NL308 cells overexpressing mAChRs. Broadly speaking, the principal effects fell into two categories: the odd-numbered receptors (m1 and m3) activated phospholipase C and increased inositol trisphosphate/Ca2+, as bradykinin did, whereas the even-numbered receptors (m2 and m4) inhibited adenylate cyclase via a pertussis toxin (PTx)-sensitive G-protein in NG108-15 cells. But all four types of NL308 cells overexpressing each m1, m2, m3 and m4 receptor activated phospholipase C, while keeping the PTx-sensitivity in m2/m4, but not in m1/m3 receptors. Coupling to ion channel effectors showed a comparable dichotomy in NG108-15 cells, while cross-activation occurred in NL308 cells.

Animals↗

Functional coupling of the delta-, mu-, and kappa-opioid receptors to mitogen-activated protein kinase and arachidonate release in Chinese hamster ovary cells.

To examine whether the mitogen-activated protein kinase (MAPK) cascade and phospholipase A2 (PLA2) are involved in the signal transduction mechanism of the opioid receptor, the delta-, mu-, and kappa-opioid receptors were stably expressed from cDNA in Chinese hamster ovary cells. Activation of the delta-, mu-, and kappa-receptors by agonists induced a rapid and transient increase in MAPK activity accompanied by reduced electrophoretic mobility of the 42-kDa isoform of MAPK (p42), probably owing to phosphorylation. The opioid receptor-mediated increase in MAPK activity was suppressed not only by pretreatment with genistein, a tyrosine protein kinase inhibitor, but also by prolonged exposure to phorbol 12-myristate 13-acetate and pretreatment with GF 109203X, a selective protein kinase C (PKC) inhibitor, suggesting the involvement of PKC as well as tyrosine protein kinase. Furthermore, stimulation of the delta-, mu-, and kappa-receptors with opioid agonists in the presence of A23187, a calcium ionophore, resulted in an increase in arachidonate release, suggesting that PLA2 is activated by the opioid receptors when the intracellular Ca2+ concentration is elevated. Both MAPK activation and increase in arachidonate release mediated by the opioid receptors were abolished by pretreatment with pertussis toxin, suggesting that these responses are mediated by Gi or Go types of GTP-binding regulatory proteins.

Animals↗

[A study on the maternal plasma C21 steroids concentration during pregnancy].

During pregnancy, C21 steroids such as progesterone (P4), and cortisol (F), have been reported to be closely involved in uterine contraction. To clarify the association between changes in steroid hormones and the onset of delivery, we measured the concentrations of six C21 steroids in maternal blood by high performance liquid chromatography. Changes in each steroid hormone were evaluated by analysis of variance during pregnancy. Pregnenolone, a source of C21 steroids, gradually increased during pregnancy. P4 and 17P4, its metabolite, reached a peak 3 weeks before delivery and noticeably decreased thereafter. Accompanying a decrease in P4 and 17P4, 20P4 and F, its metabolite, were noticeably increased. The association among these steroid hormones was also evaluated. The correlation between P4 and F was reversed after 3 weeks before delivery. These results suggest that steroid hormones in the maternal blood begin to change dynamically about 3 weeks before delivery. In particular, a decrease in P4 and an increase in F seem to be closely related to the onset of delivery.

17-alpha-Hydroxyprogesterone↗

[Drug distribution of pelvic intraarterial infusion chemotherapy by bilateral internal iliac arterial catheter placement with coil occlusion of superior, inferior gluteal and obturator arteries].

The anticancer drug distribution in pelvic arterial infusion chemotherapy with bilateral internal iliac arterial catheter placement with coil occlusion of the superior, inferior and obturator arteries was indirectly evaluated by serially performed DSA, CTA and RI on 18 patients with pelvic malignancies. The distribution was judged to be Excellent (E), defined as uniform distribution in the entire lesion alone, in 9 of 18 patients (50%) evaluated prior to the start of the arterial infusion (AI), and as Good (G), defined as uniform distribution in the entire lesion and partly on an unaffected portion, in 9 (50%). Of the 11 patients evaluated after 7 times AI, E was found in 3 patients (27%), G in 7 (64%) and Fair (F), defined as distribution with a defect in the lesion, in one patient (9%). Of the 11 patients evaluated after 14 AI, E was found in 5 (45%), G in 4 (36%) and F in 2 (18%). Of the 7 patients evaluated after 21 AI, E was found in 2 (29%), G in 4 (57%) and F in one (14%). G was found in 2 of 2 patients (100%) evaluated after 28 AI. These results suggest that this method can maintain a favorable anticancer drug distribution even after multiple sessions of AI.

Adult↗

The rck/p54 candidate proto-oncogene product is a 54-kilodalton D-E-A-D box protein differentially expressed in human and mouse tissues.

Expression of the RCK gene, which is a target gene on 11q23 of the t(11;14) (q23;q32) translocation in the B-cell lymphoma cell line RC-K8, was studied by Northern and Western blot analyses. The RCK gene product is a member of the D-E-A-D box protein/RNA helicase family. With the use of Northern blot analysis, a 7.5-kb transcript of the RCK gene was shown to be expressed ubiquitously in human and mouse tissues. Polyclonal antibodies against the RCK gene product were raised, and the RCK gene expression pattern was examined in human and mouse tissues. Two different polyclonal anti-rck antibodies detected a specific 54-kilodalton product named rck/p54 in the majority of human and mouse tissues tested by Western blot analysis. However, rck/p54 was shown to be very low in the human brain and was not detectable in lumbar muscle and lung tissues, although RCK mRNA is abundantly present in these tissues. It is of interest that malignant transformed human cells arising from tissues with low or no expression of rck/p54, such as neuroblastoma, glioblastoma, rhabdomyosarcoma, and lung cancer cell lines, produced a moderate amount of rck/p54 protein, suggesting that rck/p54 plays a role in tumorigenesis. In addition, the rck/p54 protein was localized to cytoplasm by immunostaining with the use of laser microscopy and by subcellular fractionation.

Amino Acid Sequence↗

[Effect of the GH-PRL superfamily on circulating plasma insulin-like growth factor-1].

To elucidate the effects of growth hormone (GH), prolactin (PRL), and human placental lactogen (hPL) on the regulation of insulin-like growth factor (IGF-1), we compared plasma IGF-1 levels, the pattern of circulating IGF-1-IGF-binding protein complexes (IGF-1 complexes), and unsaturated binding protein (USBP) levels among 1) naturally growing Wistar rats at several developmental stages, 2) rats subcutaneously administered GH, and 3) hypophysectomized rats treated with each of the three hormones. We further evaluated the in vitro secretion of IGF-1 by primary cultured rat hepatocytes, following exposure to the hormones singly or in combination. Plasma IGF-1 and USBP levels were determined by radioimmunoassay and competitive radioassay, respectively. IGF-1 complexes were separated from plasma and culture medium by Sephadex G150 and HPLC gel-chromatography, respectively. The results were as follows. 1) In naturally growing rats, plasma IGF levels were low during fetal life and after birth until 28 days of age, and thereafter increased rapidly to reach an adult level by 35 days. At 35 days, the molecular distribution of IGF-1 switched from an infantile pattern (only 40Kd IGF-1 complex) to an adult form (IGF-1 complexes with both 40Kd and 150Kd proteins). In addition, 150Kd USBP became detectable after 28 days. 2) Administration of GH for 3 days to 13-day-old rats induced 150Kd USBP 9 days earlier than in controls, while plasma IGF-1 levels remained comparable throughout the period examined. 3) In the hypophysectomized rats, plasma IGF-1 levels decreased to approximately one fifth of those in untreated rats, accompanied by the disappearance of 150Kd USBP and 150Kd IGF-1 complex. However, when GH (but not PRL or hPL) was continuously administered for 72 hrs, plasma IGF-1 levels and the circulating profile of IGF-1 complexes were nearly restored to those in control rats. 4) Addition of GH (but not PRL) to the culture medium caused hepatocytes to secrete IGF-1, consisting of only the 40Kd IGF-1 complex. This effect was blocked by the simultaneous addition of hPL with GH. These findings indicate that, of the hormones analyzed, GH is the most important regulator of the plasma IGF-1 concentration and circulating complex forms during the developmental periods in rats, as is also thought to be the case in humans.

Animals↗

Promoter analysis of seed storage protein genes from Canavalia gladiata D.C.

A number of A/T-rich sequences and a CATGCAT/A sequence are contained in the 5'-upstream regions of the genes encoding concanavalin A (Con A) and canavalin, two major seed storage proteins of Canavalia gladiata D.C. To study the role of these sequences in the seed-specific gene expression, we constructed 5'-deletion mutants and examined the transient expression of beta-glucuronidase reporter gene by particle bombardment and the stable expression by Agrobacterium-mediated transformation of tobacco plants. Positive regulatory elements were located in the -894/-602 and -602/-74 regions of the Con A gene, and in the -428/-376, -281/-155 and -155/-50 regions of the canavalin gene. In addition, the results suggested that the A/T-rich sequences in the 5'-upstream region of the Con A gene play a role in transcriptional activation, but that those of the canavalin gene have little effect on the gene expression. The CATGCAT/A sequence was not sufficient by itself for high levels of expression of both the Con A and canavalin genes. The canavalin polypeptide amounted to about 1% of the total extractable protein in the transgenic tobacco seeds, but the Con A polypeptide was not detected in the extractable protein.

Base Sequence↗

Successful expression in pollen of various plant species of in vitro synthesized mRNA introduced by particle bombardment.

Gold particles coated with beta-glucuronidase (GUS) mRNA with a 5' cap structure that had been synthesized in vitro were introduced, by use of a pneumatic particle gun, into pollen grains of lily (Lilium longiflorum), freesia (Freesia refracta) and tulip (Tulipa gesneriana). A fluorometric assay for the GUS activity indicated that in vitro synthesized GUS mRNA introduced into these pollen cells by particle bombardment was successfully expressed. GUS activity in extracts of the bombarded lily pollen became detectable fluorometrically within 30 min after bombardment, peaked at 6 h, then gradually decreased. This activity changed as a function of the developmental stage of the pollen cell of lily.

Gene Expression↗

Oxygen embolism due to hydrogen peroxide irrigation during cervical spinal surgery.

Hydrogen peroxide is used to cleanse and irrigate wounds. As it decomposes immediately into water and oxygen on contact with organic tissue, it is usually regarded as a safe agent. We report a case of oxygen embolism associated with hydrogen peroxide irrigation of the surgical field during anterior fusion of the cervical vertebrae. It was accompanied by precipitous hypotension and decrease in pulse oximetry oxygen saturation and end-tidal CO2 tension. Semi-closed spaces formed under the apatite dowel and between the apatite dowel and vertebral bodies may have precipitated the absorption of oxygen bubbles into the vasculature. Although this case was associated with a rapid recovery and uneventful sequelae, it discourages the use of hydrogen peroxide in this procedure because of the potential hazards including cardiovascular collapse.

Carbon Dioxide↗

Coupling of the cloned mu-opioid receptor with the omega-conotoxin-sensitive Ca2+ current in NG108-15 cells.

Voltage-dependent Ca2+ currents were measured in NG108-15 neuroblastoma x glioma hybrid cells transformed to express the rat mu-opioid receptor by the whole-cell configuration of the patch-clamp technique with Ba2+ as charge carrier. A mu-opioid receptor-selective agonist, [D-Ala2,N-Me-Phe4,Gly5-ol]-enkephalin caused significant inhibition of voltage-dependent Ca2+ currents in mu-receptor-transformed NG108-15 cells but not in nontransfected or vector-transformed control cells. On the other hand, a delta-opioid receptor-selective agonist, [D-penicillamine2,D-penicillamine5]enkephalin, induced inhibition of voltage-dependent Ca2+ currents in both control and mu-receptor-transformed cells, which is mediated by the delta-opioid receptor expressed endogenously in NG108-15 cells. The inhibition of voltage-dependent Ca2+ currents induced by [D-Ala2,N-Me-Phe4,Gly5-ol]enkephalin [D-penicillamine2,D-penicillamine5]enkephalin was reduced by pretreatment of the cells with pertussis toxin or omega-contoxin GVIA. These results indicate that the mu-opioid receptor expressed from cDNA functionally couples with omega-contoxin-sensitive N-type Ca2+ channels through the action of pertussis toxin-sensitive G proteins in NG108-15 cells.

Animals↗

Molecular and cytological characterization of a highly repeated DNA sequence in Raphanus sativus.

A highly repeated DNA sequence with a repeat unit of ca. 180 bp was found in genomic DNA HindIII-digests of Raphanus sativus. The repeating units of six isolated, independent clones were sequenced. These units have 177 or 178 bp, are 36% G+C in their DNA base composition, and show 90% sequence homology. The copy number of this 180-bp repeat unit is about 0.5 x 10(6) per diploid genome. In situ hybridization analysis with the repeating units as the probe and C-banding analysis indicated that the repeated DNA sequence of R. sativus is closely associated with the major C-heterochromatins in the proximal regions of all 18 chromosomes at mitotic metaphase.

Base Composition↗

Cloning and nucleotide sequence of a leaf ferredoxin-nitrite reductase cDNA of rice.

A ferredoxin-nitrite reductase (EC 1.7.7.1) cDNA was isolated and sequenced from a lambda gt 11 cDNA library constructed from nitrate-induced greening shoots of rice (Oryza sativa L.) seedlings. The nucleotide sequence of the cDNA clone contains an open reading frame of 1788 nucleotides. There exists a strong bias for the third codon usage of G/C (95.5%) as in the case of the maize enzyme. The deduced amino acid sequence shows an overall homology to the maize (81%) and the dicot enzymes (70-74%), suggesting that the primary structure of ferredoxin-nitrite reductase is highly conserved in higher plants.

Amino Acid Sequence↗

Introduction of DNA into sea urchin eggs by particle gun.

We have applied the particle gun method, which was developed to introduce DNA into plant cells, to sea urchin eggs and have obtained excellent expression of the introduced DNA in the embryos. The expression can be normalized by concomitantly-introducing a reference construct. The method provides a new approach to quantitative analysis of cis-regulatory elements in sea urchin embryos.

Animals↗

[Maternal nutritional states and serum insulin-like growth factor-I (IGF-I) concentrations in normal and abnormal pregnancy].

It is well known that serum IGF-I concentrations are regulated endocrinologically since IGF-I has a growth-promoting action as a mediator of growth hormone. However, recent reports suggest that nutritional states influence serum IGF-I concentration because IGF-I shows anabolic effects like insulin. The aim of this study was to clarify the influences of maternal nutritional states or metabolism on the IGF-I concentrations in normal and abnormal pregnancy. In normal pregnant women, a significant positive correlation was indicated between serum IGF-I concentrations and maternal weight gain during pregnancy or serum triglyceride levels, and a significant negative correlation was observed between serum IGF-I concentrations and serum total protein levels. In the cases complicated with hyperemesis or hyperthyroidism during early gestation, a marked reduction of maternal body weight was observed, and serum IGF-I concentration was extremely low compared with that in normal pregnant women, but serum IGF-I levels gradually increased as the maternal body weight recovered after treatment by intravenous hyperalimentation or an anti-thyroid drug. In cases of severe toxemia of pregnancy, maternal weight gain and serum triglyceride levels were markedly increased, but serum IGF-I levels were significantly lower compared with those in normal pregnant women in the same gestational age. In severe toxemia of pregnancy, there was no significant correlation between serum IGF-I levels and maternal weight gain or serum triglyceride levels, and these results may be influenced by such abnormalities as water retention, hemoconcentration, severe hypoproteinemia and severe negative nitrogen balance not found in normal pregnancy. In conclusion, it is considered that IGF-I concentration is regulated not only by endocrinological factors, but also by metabolic factors in maternal circulation during pregnancy, and the measurement of maternal IGF-I concentration seems to be a useful parameter to evaluate the maternal nutritional states.

Adult↗

[The relationship between the changes in insulin-like growth factor-1 (IGF-1) and the nutritional states evaluated by nitrogen balance in pregnant rats].

The effects of nutrition on serum insulin-like growth factor-1 (IGF-1) concentrations during pregnancy of rats were investigated by using rat cultured hepatocytes in vitro, and by the assessment of nitrogen balance in vivo. IGF-1 concentration was measured by radioimmunoassay, and nitrogen balance was calculated by Pregl-Dumas method. The results were as follows: (1) Cultured rat hepatocytes produced IGF-1 in medium and it was significantly stimulated by the addition of various concentrations of glucose (1.1-4.4 mM) and/or several amino acid concentrations in a dose-related manner. (2) Serum IGF-1 concentrations, which indicated 368.6 +/- 143.8 ng/ml in a non-pregnant fed state, markedly decreased in a fasted state, reaching the levels of 143.8 +/- 30.4 ng/ml after 72 hours fasting. Nitrogen balance in these fasted rats also decreased according to the fasted period. (3) In early pregnancy (Day 0-12), serum IGF-1 concentrations were indistinguishable from those of non-pregnant fed rats. It gradually declined after the 13th day of pregnancy and reached the minimum levels of 77.0 +/- 12.1 ng/ml on the 21st day. On the other hand, mean nitrogen balance which was calculated from the difference of nitrogen retention in the maternal body and that in the fetal body, also decreased after 13 days of pregnancy and reached the levels of 14.9 g/day on the 21st day of pregnancy. These results suggested that IGF-1 concentrations in rat serum and conditioned medium might be regulated by nutritional factors, i.e., glucose and/or several amino acids. The curious profiles of IGF-1 concentrations observed in pregnant rats might be due in part to the effects of nutritional changes between the maternal and fetal body, especially, the changes of protein metabolism represented by the nitrogen balance.

Animals↗