Biomedical subjects
Publications and source records attributed to H Morikawa.
Acute ipsilateral pulmonary oedema is a well documented complication of the treatment of lung collapse secondary to pneumothorax, pleural effusion and atelectasis. We present a case of bilateral re-expansion pulmonary oedema following removal of an intrathoracic haematoma. High protein concentration of the oedema fluid suggests increased pulmonary vascular permeability as a cause of this pulmonary oedema.
A nitrite reductase (NiR) gene was recovered from Arabidopsis thaliana genomic library by the homology with a cDNA of spinach NiR and sequenced. Based on the comparison with the spinach cDNA, the Arabidopsis NiR gene was concluded to contain 4 exons [exon 1 of 376 bp (beginning with ATG start codon), exon 2 of 355 bp, exon 3 of 289 bp and exon 4 of 741 bp (ending at TGA stop codon)] and 3 introns (intron 1 of 196 bp, intron 2 of 81 bp and intron 3 of 77 bp). This conclusion was confirmed by the analysis using the RT-PCR method. The deduced amino acid sequence of the coding region of the Arabidopsis NiR gene had high similarities with those of NiR genes of other plants including spinach.
This study explored both universal features and cultural variation in maternal speech. Japanese and American mothers' speech to infants at 6, 12, and 19 months was compared in a cross-sectional study of 60 dyads observed playing with toys at home. Mothers' speech in both cultures shared common characteristics, such as linguistic simplification and frequent repetition, and mothers made similar adjustments in their speech to infants of different ages. American mothers labeled objects more frequently and consistently than did Japanese mothers, while Japanese mothers used objects to engage infants in social routines more often than did American mothers. American infants had larger noun vocabularies than did Japanese infants, according to maternal report. The greater emphasis on object nouns in American mothers' speech is only partially attributable to structural differences between Japanese and English. Cultural differences in interactional style and beliefs about child rearing strongly influence the structure and content of speech to infants.
Intra-uterine growth retardation, intra-uterine fetal death and pre-eclampsia have common abnormalities: A reduction of uteroplacental perfusion, lack of vasodilation of spiral arteries and subsequent thrombosis. These physiological processes have been explained by an imbalance between prostacyclin and thromboxane A2 production. Many studies have suggested that treatment with low-dose aspirin and steroids is effective in preventing pregnancy loss or pre-eclampsia, but the mechanism has not been established. We evaluated the effectiveness of these therapies in patients at risk for pregnancy loss with the aspect of intracellular ionized calcium mobilization. Low-dose aspirin directs the prostacyclin/thromboxane A2 balance to the dominance of prostacyclin and steroids suppress the activities of lupus anticoagulant or antiphospholipid antibodies. The intracellular ionized calcium concentration in platelets is decreased significantly after these therapies. Concerning the pathological examination of placenta, there were deposits of fibrin in only 2 out of 8 cases and there were no abnormal findings in the other 6 cases. These data show that the aggregation of platelets is suppressed in microvascular circulations. These therapies do not cause any adverse effect on the mother or fetus. It is concluded that low-dose aspirin therapy with steroids is useful for patients with a poor obstetrical history.
In order to clarify the pathophysiological significance of changes in intracellular ionized calcium and sodium levels in pregnancy induced hypertension (PIH), the intracellular ionized calcium concentration in platelets (p-[Ca2+]i) and the intracellular ionized sodium concentration in red blood cells (r-[Na+]i) were measured simultaneously in PIH women in the third trimester. p-[Ca2+]i in the first trimester showed a slightly greater increase than in the women of normal luteal phase. In the second trimester, p-[Ca2+]i decreased significantly compared to first trimester, and the third trimester and first trimester levels were the same. In women with mild and severe PIH, the levels in both groups were significantly increased compared with that in normal pregnant women. Thus mechanisms not associated with platelet activation were considered as the cause of the increase of p-[Ca2+]i of women with PIH. r-[Na+]i in mild and severe PIH were also significantly increased compared to normal pregnancy. No correlation between p-[Ca2+]i and r-[Na+]i and diastolic blood pressure was observed in normal pregnancy, but a positive correlation was observed in PIH. When the male platelets were incubated with serum from non-pregnant or normal pregnant women, p-[Ca2+]i did not show any significant changes. On the other hand, p-[Ca2+]i was significantly increased after the incubation with serum from PIH women. Moreover, p-[Ca2+]i was significantly increased after the incubation with 17 beta-estradiol, parathyroid hormone (PTH), or endothelin-1 (ET-1). These data suggest that the increase of p-[Ca2+]i and r-[Na+]i in PIH is important in the initiation and maintenance of hypertension by influencing peripheral vascular resistance, and also various factors in the serum of PIH women may contribute to the accumulation of intracellular ionized calcium in patients with PIH.
Successful transient expression of beta-glucuronidase (GUS) in Arabidopsis thaliana leaves and roots and Brassica napus stems was obtained after gene delivery with a pneumatic particle gun driven by compressed air. Effects of the pneumatic pressure used to accelerate the particles (accelerating pressure; 85 to 200 kg/cm2) and of preculture periods of plant tissues (0 to 6 days) on the efficiency of gene delivery were studied. In A. thaliana leaves, best results were obtained at 115 kg/cm2 of accelerating pressure and 3 days of preculture. In A. thaliana roots, the optimum was at 200 kg/cm2 of accelerating pressure and 3 days of preculture. These results indicate that both preculture period and accelerating pressure are vital factors that determine the efficiency of gene delivery by particle gun.
Preeclampsia is characterized by enhanced pressor responsiveness to angiotensin II. This report summarizes studies by our laboratory to investigate possible roles for calcium, sodium, membrane pumps, and the vasoactive hormones, atrial natriuretic peptide (hANP) and endothelin, in modulating the change in vascular reactivity characteristic of preeclampsia. Urinary calcium excretion, 1 alpha-25(OH)2D3 levels, and serum free calcium levels were all decreased, whereas parathyroid hormone levels and intraplatelet calcium concentrations were increased in women with preeclampsia. Erythrocyte sodium content was elevated, while red blood cell membrane Na-K-ATPase activity was decreased in patients with severe disease. Preeclamptics also had elevated levels of hANP, which failed to increase further when saline was infused or when blood pressure was increased transiently with angiotensin II administration. Finally, endothelin levels that are reduced in normal gestation, were increased in preeclampsia. While the cause of increased vascular reactivity is still unclear, there appear to be changes in the intracellular cation environment, combined with loss of compensating mechanisms, both at the membrane and humoral level, as well as enhanced concentrations of a potent vasoconstrictor in blood; all which lead to increases in vasoreactivity and blood pressure in preeclampsia.
Plasmid DNA harboring the beta-glucuronidase (GUS) gene, coated on gold particles, was delivered into cultured tobacco (Nicotiana tabacum L. cv Bright Yellow-2) cells using a pneumatic particle gun. Cytological analyses of intracellular location of the introduced gold particles before and after GUS expression assay indicated that more than 90% of GUS-expressing cells after bombardment received a DNA-coated particle in their nucleus.
Plasmid DNA pB1221 harboring beta-glucuronidase gene was delivered to synchronized cultured tobacco (Nicotiana tabacum L. cv Bright Yellow-2) cells of different cell cycle stages by a pneumatic particle gun. The cells bombarded at M and G(2) phases gave 4 to 6 times higher transformation efficiency than those bombarded at the S and G(1) phases.
The aim of this study was to clarify the effects of maternal hyperglycemia on fetal growth in rats. In streptozotocin (STZ)-induced diabetic rats, maternal serum glucose levels during pregnancy were controlled by daily injection of NPH insulin or saline from day 3 to 21 of pregnancy. The body weight, hepatic glycogen content and serum concentrations of insulin and Insulin-like Growth Factor-I (IGF-I) in fetuses from these rats were measured on Day 21 of pregnancy. Fetal body weight positively correlated with maternal mean blood glucose (MBG) during pregnancy in the groups of diabetic mothers whose MBG was less than 220 mg/dl, whereas a negative correlation was observed in the groups whose MBG was more than 220 mg/dl. In addition, a similar correlation between hepatic glycogen content, serum concentrations of insulin or IGF-I and maternal MBG was observed. On the other hand, in the culture of fetal rat hepatocytes, glycogen content indicated a dose-related increase according to the increase in glucose concentration in the medium. These results suggest that the growth retardation observed in rats whose maternal mean glucose level is higher than 220 mg/dl is not caused by abnormalities in the metabolic function of the fetal metabolic organ (liver), but it is caused by a decrease in the production and/or secretion of growth-promoting factors (for example insulin and IGF-I) in the fetuses.
In order to elucidate the roles of Insulin-like Growth Factors (IGF-I, -II) in human pregnancy, the levels of IGF-I and IGF-II, the distribution of binding proteins for IGF-I or IGF-II and profiles of unsaturated somatomedin binding proteins (USBP) were estimated in maternal and cord plasma. IGF-I levels in maternal plasma gradually elevated in late gestation, reaching 304.4 +/- 130.1ng/ml at term, and were significantly higher than those in nonpregnant women (188 +/- 58). IGF-II levels, which were 414.9 +/- 75.4ng/ml in women in the third trimester of gestation, did not produce any remarkable changes in the levels in nonpregnant women (395.9 +/- 72.6). On the other hand, IGF-I in cord plasma also increased according to gestational age, reaching 37.3 +/- 14.6ng/ml at term, but it was significantly lower than that in maternal weight (r = 0.50, p less than 0.005) and relative birth weight (r = 0.41, p less than 0.005). IGF-II in cord plasma showed no significant changes during gestation, however, IGF-II levels in AFD (appropriate for date) newborns delivered at term (203.8 +/- 59.4) were significantly lower than those in maternal plasma. And they had no positive correlations with birth weight and relative birth weight. On Sephadex G150 gel-chromatography of cord plasma from AFD newborns at term, more than 70% of immunoreactive IGF-I in plasma was eluted at 150K region, and 150K USBP could be detected as observed in adult plasma. On the other hand, most of the immunoreactive IGF-II was eluted at 40K region, and 150K USBP was not detected in AFD newborns at term. In adult plasma, most of the immunoreactive IGF-II was eluted at 150K region, but 150K USBP could not be detected. From these results, it is supposed that IGF-I plays an essential role in fetal growth rather than IGF-II.
A simulation study to evaluate the errors in rate constants of the three compartment model using the weighted integral method was performed. Ten combinations of 7 kinds of weight functions, the errors were tested in 18F fluorodeoxyglucose (18FDG) study. The error factors arising in PET measurement were statistical noise, cerebral blood volume, time shift and scanning time of PET measurement. Errors in each rate constant were within the range of 10 percent and those in k1k3/(k2+k3) within 1 percent. The weighted integral method was confirmed to be a faster method than the conventional least squares method within a reasonable error range.
In order to investigate the regulating mechanism of Atrial Natriuretic Polypeptide (ANP) in women with Pregnancy Induced Hypertension (PIH), we measured plasma ANP levels with or without loading tests such as Angiotensin-II loading test or NaCl loading test. Plasma ANP in normal pregnancy gradually increased with advancing gestation, and decreased immediately after parturition. In PIH cases the ANP concentration was significantly higher (mild PIH 156.7 +/- 9.9 pg/ml, severe PIH 165.8 +/- 12.2 pg/ml) than in normal pregnancy cases (138.2 +/- 3.2 pg/ml). In Angiotensin-II loading, a significant positive correlation (r = 0.68, p less than 0.01) between the variance of mean arterial blood pressure (delta MAP) and that of ANP (delta ANP) was observed in normal pregnant women of third trimester, whereas in mild PIH cases a significant negative correlation (r = -0.59, p less than 0.01) was noted between them, and in severe PIH cases there existed no significant correlation. In normal pregnancy and in mild PIH, plasma ANP showed a 15.2% increase at fifteen minutes after 5% NaCl loading. In severe PIH there were no significant change in plasma ANP during and at fifteen minutes after NaCl loading test. From these results, it is suggested that the onset, the duration or the aggravation of hypertension in pregnancy may be partly due to the abnormality of ANP secretion.
In order to clarify the potential roles of glucagon for energy induction during the perinatal period, the developmental changes of serum glucagon concentration, the ontogenesis of hepatic glucagon receptor and glucagon-sensitive adenylate cyclase system were estimated in comparison with insulin in rats. In fetal rats on day 18 to 20 gestation, serum glucose levels and hepatic glycogen contents gradually increased as pregnancy progressed. The levels of serum glucagon and its binding to liver microsomal membranes were significantly lower than in adults, and glucagon-sensitive c-AMP production was also markedly suppressed. On day 21 of gestation, hepatic glycogen contents markedly increased to the maximal level, serum glucagon level increased, and glucagon receptors in the fetal liver were already estimated at the same level as in the adult. However, glucagon-sensitive c-AMP production was still suppressed the same as in the fetuses of earlier gestational ages. On the other hand, serum insulin levels in fetuses were higher than those in adults, and the abundant receptor could also be observed in liver microsomal membranes. After delivery, serum glucose rapidly decreased with a marked decline of hepatic glycogen contents until 5 hours in the neonatal period. Serum glucagon and its hepatic receptors were significantly increased with a gradual development of the glucagon-sensitive adenylate cyclase system. Conversely, serum insulin levels were suppressed without any remarkable change in its receptor. From these results, it is suggested that glucagon plays an important role in the neonatal adaptation mechanism, especially in the production of endogenous glucose in place of the transplacental supply from the mother, such effects of glucagon are already initiated by the induction of its receptor in target tissues in the fetus on late gestation.
The authors have already reported that the bone density of normal pregnant women might be kept at the same density as in normal non-pregnant women. However, it might be decreased in women with pregnancy induced hypertension (PIH) by estimating serum calcium levels, serum levels of calcium regulating hormones and calcium secretion into the urine. In order to demonstrate this theory, the degree of bone density in the second metacarpal bone of normal or PIH pregnant women was measured by X-ray using microdensitometry method (MD method). In MD method, six indices, such as MCI, d, GSmin, GSmax, sigma GS/D and densitometric pattern, are calculated by computer analysis of the X-ray of the bilateral hands. By the evaluation of the degree of bone atrophy, scores such as 0 better than the regression line of healthy women, which were prepared according to each age, 1 until 1 delta to the aggravation, 2 until 2 delta, and 3 more than 2 delta were totaled and evaluated as normal, initial stage of bone atrophy, 1st degree of bone atrophy, 2nd degree of bone atrophy and 3rd degree of bone atrophy for 0-3 scores, 4-9 scores, 10-12 scores and 13-18 scores, respectively (delta = 1 S.D.). The metacarpal index (MCI) of normal pregnant women in 3rd trimester was more than the mean in all cases, while cases more than 2 delta of the mean were noted in 29.4% of mild PIH and 11.8% of severe PIH, and a decreasing tendency of width of bone cortex was considered in PIH women. On the other hand, width of bone marrow (d) increased significantly in mild and severe PIH women. In the index for the density of only bone cortex area (GSmax) in PIH women, cases less than mean -1 delta were noted in 29.3% of mild types and in 11.8% of severe types respectively, and a high incidence was noted even though it was insignificant compared with 7.4% of normal pregnant women. In the index of the densities of bone cortex and bone marrow (GSmin), cases less than mean -1 delta were noted more frequently in PIH women than normal pregnant women, but in the index of bone density per unit length (sigma GS/D) no differences were noted between PIH and normal pregnant women.(ABSTRACT TRUNCATED AT 400 WORDS)
In order to clarify the potential role of IGF-I in fetal growth, the dynamics of IGF receptor were investigated in comparison with insulin receptor in human and rat fetuses. In humans, the serum levels of IGF-I measured by IGF-I radioimmunoassay after acid-ethanol extraction were significantly lower in fetuses than in adult controls. Conversely, serum insulin levels in fetuses were not indistinguishable from those in adults. On the other hand, specific binding of 125I-IGF-I to human fetal erythrocytes was 2.3%, which was significantly higher than that of adult women (1.6%). Insulin binding to the erythrocytes was also higher in human fetuses than in adult controls (cord: 3.8%, adult: 3.0%). By Scatchard analysis, the changes in the specific binding of IGF-I and insulin were mainly due to the changes in the binding capacity rather than those in the binding affinity. Additionally, IGF receptor on human fetal erythrocytes was recognized as type I IGF receptor, because the binding of 125I-labelled IGF-I and 125I-labelled IGF-II could be displaced by the addition of cold IGF-I, IGF-II and insulin. In rats, serum levels of IGF-I were also much lower in fetuses than in adult controls. Specific binding of 125I-IGF-I to liver microsomal membranes was 34.3% (per 400 micrograms protein) in fetal rats (D20), which was significantly higher than that of adult rats (3.2%). Scatchard analysis indicated that these changes in 125I-IGF-I binding was chiefly due to the changes in binding capacity. On the other hand, serum insulin levels increased with progress of pregnancy, and specific binding of insulin to microsomal membranes of fetal liver increased on D21 of gestation, mainly due to the increase in binding affinity rather than binding capacity. The bindings of 125I-labelled IGF-I and 125I-labelled IGF-II to fetal liver microsomal membranes were clearly displaced by cold IGF-I and IGF-II but not by excess of cold insulin, indicating that the receptor was type 2 IGF receptor. These results suggest that IGF-I possesses much more receptor in fetal tissues than in adult tissues despite its lower concentration in fetal sera. It is speculated that IGF-I may play an important role in fetal growth and development.
IGF-I/SMC shows mitogenic activities in a wide variety of cell types and stimulates cell growth in vitro and in vivo. Unlike most other peptide hormones, IGF-I/SMC circulates in the plasma as macromolecular complexes with specific plasma binding proteins, approximate molecular weight of 150K and 40K daltons. In order to elucidate the roles of IGF-I/SMC for fetal and postnatal development, the levels of plasma IGF-I/SMC, distribution of circulating IGF-I/SMC on its binding proteins, and profiles of unsaturated somatomedin binding proteins (USBP) were estimated in newborns and a growth-retarded infant (leprechaunism). The concentrations of IGF-I/SMC in cord plasma increased gradually after the 28th week of gestation and reached 37.3 +/- 14.6 ng/ml (Mean +/- S.D.) in full term infants. Although the levels of IGF-I/SMC in cord plasma were significantly lower than those in non-pregnant women (188 +/- 58), they showed a positive correlation with birth weight and relative birth weight (R.B.W.: percentage comparison to the average birth weight of normal infants in the same gestational week). In adult plasma, immunoreactive IGF-I/SMC was eluted predominantly in 150K dalton region (73.5%) and to a lesser extent (26.5%) in 40K dalton, and two apparent peaks of USBP could also be determined in both 150K and 40K dalton regions. On the other hand, in fetal plasma 84.4% of immunoreactive IGF-I/SMC was eluted in 40K region on the 20th week, but on the 26th week, 71.6% of IGF-I/SMC was eluted in 150K region and after the 35th week, more than 70% of IGF-I/SMC was determined in 150K region as observed in adult plasma. However, 150K.USBP could not be detected in cord plasma obtained from appropriate-for-date(AFD) infants until after the 35th week of gestation. Additionally, a positive correlation was demonstrated between 150K.USBP/40K.USBP ratio and birth weight. Some cases of small-for-date(SFD) infants whose IGF-I/SMC circulated mainly as 150K complex could catch up on their growth early in postnatal life. However, in the SFD newborns, if either 150K.USBP or 150Kcomplex of IGF-I/SMC could not be detected, their growth spurt was remarkably delayed until a year after birth. Furthermore, the similar disorders of IGF-I/SMC distribution and its USBP profile were also observed in the case of leprechaunism, who showed severe intrauterine and postnatal growth retardation.(ABSTRACT TRUNCATED AT 400 WORDS)
Leprechaunism is a rare genetic disorder characterized by physical abnormalities, intrauterine and postnatal growth retardation, poorly developed subcutaneous fat and muscle at birth, and early death. This patient, who was a 1.5 year-old female with typical clinical features of leprechaunism, had relatively high levels of plasma GH and IGF-I/SMC but no glucose intolerance or insulin resistance. Studies were undertaken to elucidate (1) the differences among some kinds of methods for IGF-I/SMC measurement, (2) the distribution patterns of IGF-I/SMC between two kinds of its binding protein (SMBP) in plasma, and (3) the dynamics of IGF-I/SMC receptor in her erythrocytes and liver microsomal membranes. The results were as follows: (1) The level of IGF-I/SMC measured by Nichols radioimmunoassay kit was 1.33U/ml, which was higher than that of infants the same age. Conversely, it was lower than that of the control which was measured by radioimmunoassay using recombinant IGF-I/SMC after acid-ethanol or Seppak C18 extraction. (2) By Sephadex G150 gel-chromatography, immunoreactive IGF-I/SMC was eluted predominantly in 150K region, and two apparent peaks of unsaturated somatomedin binding protein (USBP) were determined in a neonatal infant (appropriate to date), a normal adult and an infant of the same age as this patient. On the other hand, immunoreactive IGF-I/SMC was located only in the fractions corresponding to 40K region, and only one peak of USBP could be estimated in the region of 40K dalton. (3) The IGF-I/SMC receptor in the patient's erythrocytes possessed significantly lower binding affinity but higher binding capacity in comparison with that of the normal neonate and adult. In addition, the receptor in liver microsomal membranes obtained from this patient at autopsy also indicated lower affinity but higher capacity than that of fetuses at more than 19 weeks of gestation. This was coincident to that of fetuses less than 19 weeks of gestation. These results suggested that this patient resembled the intrauterine fetus before midgestation not only in the co-relationship among GH, IGF-I/SMC and its binding proteins, but also in the characteristics of its receptor. The severe growth retardation existing in this patient may be, at least partly, due to the abnormality and/or immaturity of IGF-I/SMC function. It is speculated that leprechaunism could be classified in relation to fetal growth mechanism by aspects of biological functions of IGF-I/SMC during development.