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We report the results of stochastic molecular dynamics simulations for the structural formation of charged dendrimers and dendrimer-based star polymers. The variation in the radius of gyration explains quite well recent small-angle neutron-scattering experiments for higher-generation charged dendrimers under different pH conditions. We also clarify the properties of effective interaction between dendrimers for weak and strong electrostatic couplings in an aqueous solution.

¹³C and ¹²⁹Xe high-pressure (HP) magic-angle spinning (MAS) NMR was applied to a polystyrene/poly(vinyl methyl ether) (PS/PVME) = 50/50 blend under Xe pressure range of 0.0−4.0 MPa for investigating effects of the dissolved Xe atoms on the segmental motions of the individual component polymers. It is shown that the chemical shift of ¹²⁹Xe dissolved in the blend moves to the high-frequency side and the line becomes narrow with increasing Xe gas pressure. The ¹²⁹Xe higher-frequency shift is explained in terms of an increase of the Xe concentration in the blend. The line narrowing suggests that the Xe atomic diffusion is enhanced with increasing Xe concentration in the blend. On the other hand, the ¹³C line widths under MAS and ¹H dipolar decoupling (DD) evidently show that the dissolved Xe atoms enhance the segmental motions of the individual component polymers (plasticization effect) at Xe gas pressures higher than 1.0 MPa. Furthermore, the observed pressure and temperature dependence of the line widths demonstrates that the motional frequency difference between PS and PVME at high pressures is less than that observed at high temperatures. It is concluded that the dissolved Xe atoms not only enhance the segmental motions of PS and PVME but also work to reduce the motional heterogeneity in the blend.

Urinary trypsin inhibitor (UTI) forms membrane complexes with UTI-binding proteins (UTI-BPs) and initiates modulation of urokinase-type plasminogen activator (uPA) expression, which results in UTI-mediated suppression of cell invasiveness. It has been established that suppression of uPA expression and invasiveness by UTI is mediated through inhibition of protein kinase C-dependent signaling pathways and that human chondrosarcoma cell line HCS-2/8 expresses two types of UTI-BPs; a 40-kDa UTI-BP (UTI-BP(40)), which is identical to link protein (LP), and a 45-kDa UTI-BP (UTI-BP(45)). Here we characterize binding properties of UTI-BPs.UTI complexes in the cells. In vitro ligand blot, cell binding and competition assays, and Scatchard analyses demonstrate that both UTI-BP(40) and UTI-BP(45) bind (125)I-UTI. A deglycosylated form of UTI (NG-UTI), from which the chondroitin-sulfate side chain has been removed, binds only to UTI-BP(40). Additional experiments, using various reagents to block binding of (125)I-UTI and NG-UTI to the UTI-BP(40) and UTI-BP(45) confirm that the chondroitin sulfate side chain of UTI is required for its binding to UTI-BP(45). Analysis of binding of (125)I-UTI and NG-UTI to the cells suggests that low affinity binding sites are the UTI-BP(40) (which can bind NG-UTI), and the high affinity sites are the UTI-BP(45). In addition, UTI-induced suppression of phorbol ester stimulated up-regulation of uPA is inhibited by reagents that were shown to prevent binding of UTI to the 40- and 45-kDa proteins. We conclude that UTI must bind to both of the UTI-BPs to suppress uPA up-regulation.

We examined the relationships among the clinical efficacies of risperidone, plasma concentrations of risperidone and its active metabolite, 9hydroxyrisperidone, and changes in plasma free MHPG pMHPG in 14 schizophrenic patients. Clinical improvement in negative symptoms of schizophrenia treated with risperidone has been associated with increased pMHPG and, in the present study, there were positive correlations between plasma 9hydroxyrisperidone concentrations and increased pMHPG levels. These results suggest that risperidone might improve negative symptoms in schizophrenia by influencing noradrenergic neurons.

Solid-state ¹³C two-dimensional (2D) exchange NMR has been applied to investigate dynamic alternation among three forms of hydrogen bonds in the poly(acrylic acid)/poly(ethylene oxide) (PAA/PEO) complex. The ¹³C CPMAS NMR spectrum of the signal for the PAA carboxyl carbon in the complex is split into three peaks corresponding to three forms of hydrogen bonds, namely, the complex form, the dimeric form, and the free form. These three peaks coalesce into a single peak at temperatures above 346 K, showing that dynamic alternation of hydrogen bonds occurs in the complex. 2D exchange NMR spectra directly show that the dissociation−association of hydrogen bonds occurs at temperatures above 329 K, which is 7 deg higher than the glass transition temperature (Tg). The exchange rates are on the order of Hz and have a wide distribution. At the same time, it was found that PAA conformational transitions occur at a rate comparable to that of the hydrogen bond alternation. On the other hand, the PEO motion shows no apparent correlation to the hydrogen-bonding dynamics. It is concluded that the hydrogen-bonding dynamics is coupled to the segmental motion of PAA in the complex.

To study the intrauterine defensive role of fetal urine, we focused urinary trypsin inhibitor (UTI) from fetal urine. Urinary trypsin inhibitor (UTI) is a glycoprotein secreted with fetal urine. Until now, its real function has been unknown. The expression of IL-8 induced by LPS were completely abolished in the presence of physiological concentration of UTI in various cells. LPS or IL-8 in the form of vaginal suppositories induced cervical ripening in rabbits. UTI applied after LPS or IL-8 could successfully inhibit the changes induced by IL-8 or LPS in the rabbit cervix. UTI or fetal urine inhibits the increase of intracellular Ca^2^+ of uterine muscle cells induced by LPS. Possibly, this regulatory effect of intracellular Ca^2^+ is involved in preventing uterine muscle contraction. UTI or fetal urine suppresses premature cervical ripening and prevents uterine muscle contraction. We conclude that UTI of fetal urine is important role in maintaining pregnancy.

It is well known that maternal fibrinogen (Fg) and subunit A of factor XIII (XIIIA) are essential for maintaining early pregnancy. We reported that they were essential from 5 weeks' gestation and were present immunohistochemically at the implantation site. Now we studied the precise localization of Fg, fibronectin (Fn), XIIIA, and subunit S of factor XIII (XIIIS) associated with the development of extravillous cytotrophoblast (EV-CTr) in the human implantation tissues and placenta. Cytotrophoblast cells were confirmed by cytokeratin immunolabeling. The results showed that in the region around the early placental bed, Fg and Fn were present at Nitabuch's layer, and XIIIA was present at the extracellular space of EV-CTrs forming the cytotrophoblastic shell adjacent to Nitabuch's layer. In the decidual stroma near Nibabuch's layer, where interstitial EV-CTrs were infiltrating, Fn was present. However, any obvious localization of Fg, XIIIA and XIIIS could not be detected. In the decidual stroma far from Nitabuch's layer, where interstitial EV-CTrs did not infiltrate, numerous XIIIA positive macrophages were detected. However, any obvious localization of Fg, Fn, plasma and platelet XIIIA, and XIIIS could not be detected. Discussion of the results leads to a hypothesis that maternal Fg, maternal XIIIA and Fn present at the site around the cytotrophoblastic shell are associated with the early placental adhesion. Also, Fn is present at the decidual stroma where interstitial EV-CTrs are infiltrating, so it may be oncofetal Fn and associated with trophoblastic outgrowth and migration. XIIIA positive macrophages and the interstitial EV-CTrs cannot be present together at the decidual stroma. However, XIIIA positive macrophages may play a role in assisting the tetomaternal adhesion.

To investigate the role of phosphatidylserine (PS) derived from the activated platelets in placental circulation, we established an artificial PS-induced intrauterine growth restriction (IUGR) model in mice and examined whether annexin V, a PS-binding anticoagulant protein, could prevent the development of IUGR in the animal experiments. The ICR mice were injected in the tail vein on days 8, 11 and 14 of pregnancy with filtered PS/phosphatidylcholine (PC) microvesicles (<0.3μm in maximal diameter). The microvesicles have a procoagulant activity which was inhibited by annexin V in a dose-dependent fashion. The mice were killed on day 18 of pregnancy and the placental and fetal weights were measured. The placental tissue specimens were examined microscopically. PS/PC vesicles induced significant reductions in fetal weights compared with PC vesicles alone. The placental tissue revealed severe congestion with fibrin depositions although the lung and kidney tissue specimens showed minimal histological changes. PS/PC microvesicles with recombinant annexin V showed no significant reductions in fetal weights in mice with PS/PC vesicles alone. These results suggest that PS from the activated platelets induces IUGR by enhancing the coagulation cascade in the placental circulation and that annexin V from the villous trophoblast prevents the development of IUGR.

Hyaluronic acid (HA) stimulates the synthesis of interleukin (IL) 8, while dehydroepiandrosterone sulphate (DHEA-S) induces the expression of IL-8 and its receptor in the human cervical fibroblast. This has led us to investigate the effect of DHEA-S on HA-induced cervical ripening. Experiments were performed in pregnant rabbits using vaginal suppositories containing 1 mg HA, 30 mg DHEA-S, 30 mg DHEA-S + 0.1 mg HA, 30 mg DHEA-S + 1 mg HA, and 500 microl Witepsol-50 base (control). The effects were evaluated by measuring collagenase, gelatinase and elastase activities, water content, neutrophil infiltration, relative collagen concentration and histological assessment. The activities of collagenase, gelatinase and elastase were significantly increased in rabbits treated with DHEA-S + 1 mg HA compared with rabbits treated with DHEA-S + 0.1 mg HA (P < 0.009, P < 0.001, P < 0.009 respectively). Water content was markedly increased in rabbits treated with DHEA-S + 1 mg HA compared with DHEA-S + 0.1 mg HA treatment (P < 0.05). Neutrophil infiltration was markedly increased, while relative collagen concentration was significantly decreased with DHEA-S + 1 mg HA compared with the DHEA-S + 0.1 mg HA approach (P < 0.001, P < 0.002). The histology of cervices treated with DHEA-S + 1 mg HA showed the density of collagen to be markedly decreased, and collagen fibres irregularly separated. Increased vascularity with massive dilatation of blood vessels was also observed in these rabbits. We conclude that DHEA-S upregulates the HA-induced cervical ripening process.

From high-resolution solid-state13C NMR spectra for the enol forms of some diketones, an average chemical shift of the carbonyl and enol carbons in dimedone is found to move remarkably downfield compared with the corresponding shift in DMSO-d6, which is ascribed to a strong intermolecular hydrogen bond in the solid state.

Throughout Japan a total of 543 cases of vitamin K deficiency occurring in infants over 2 weeks of age were reported from January 1981 to June 1985. Of these cases, 427 showed no obvious reasons for vitamin K deficiency; this sort of case is known as “idiopathic vitamin K deficiency in infancy”. Another 57 cases had bleeding episodes due to vitamin K deficiency associated with obvious hepatobiliary lesions, chronic diarrhoea, long-term antibiotic therapy, etc; this sort is called “secondary vitamin K deficiency in infacy”. The third group, consisting of 59 cases, was made up of the socalled “near miss” type, in which a haemorrhagic tendency, without any obvious clinical haemorrhage, was discovered by Normotest, at the time of mass screening in most cases. In the idiopathic group, 269 cases (63.0%) developed bleeding episodes between the 1st and 2nd months of age, and 387 cases (90.0%) were entirely breast-fed. Intracranial baemorrhage was observed in 353 cases (82.7%) of this group. Moreover, slight elevation of serum transaminase and direct type bilirubin levels were observed in the idiopathic group. Liver dysfunction of unknown origin may play some role in the onset of vitamin K deficiency in infancy.

Proton spin–lattice relaxation times (T1) were measured on a protein Streptomycessubtilisin inhibitor, in the solid state, in the presence and the absence of adsorbed 2H2O in the temperature range between −170 and 100 °C at 30 and 60 MHz. In both samples, a common relaxation process is attributed to the methyl group rotations of amino acid side chains which show minimum values of T1of 0.11 s at −105 °C at 30 MHz and 0.23 s at −80 °C at 60 MHz. In the presence of adsorbed 2H2O, another, effective relaxation process was found above 0°C, showing a minimum value of T1of 0.12 s at about 80 °C at 60 MHz. The latter relaxation process was attributed to internal motions of exposed peptide segments, a large part of which is located in the crucial enzyme-binding region of the inhibitor.

Inter-alpha-trypsin inhibitor (ITI), a human serum protease inhibitor of molecular mass 240 kDa which may release physiological derivatives, has been shown to interact with hyaluronic acid (HA), resulting in pericellular matrix stabilization (Chen, L., Mao, S.J.T., McLean, L. R., Powers, R. W., and Larsen, W. J. (1994) J. Biol. Chem. 269, 28282-28287). The purpose of this study is to determine whether ITI binding to tumor cell surface is mediated by urinary trypsin inhibitor (UTI)-receptor or cell-associated hyaluronic acid (HA). We demonstrated specific complex formation of the heavy (H) chains of ITI with HA. Binding of the H-chains of ITI to immobilized HA was detected and quantified using colorimetric immunoassays. Binding was time-, temperature-, and concentration-dependent. However, UTI and HI-8 (the carboxyl terminus of UTI) failed to bind to immobilized HA. ITI bound to HA remained functional protease inhibiting activity. After incubation of SMT-cc1 cells with purified biotinylated ITI, biotinylated ITI is bound to the cells, dissociated, and gives rise to the H-chains and UTI on the cell surface. The cell surface receptor-bound UTI derived from ITI may be the result of the limited proteolysis on the cell surface. In the cells treated with hyaluronidase, bound H-chains disappeared from the surface of the cells, while most of the cell surface ITI derivatives was present in deglycosylated UTI (28 kDa). It is suggested that the binding of ITI to the cell surface is mediated by HA on the cells. This was confirmed by the fact that the hyaluronidase-treated cells can abolish the ITI binding. The cell surface UTI formation was inhibited by diisopropyl fluorophosphate, phenylmethylsulfonyl fluoride, and eglin C, suggesting that elastase-like enzyme(s) may be responsible for the UTI formation. Preincubation of the cells with UTI did not decrease in exogenously added ITI on the cell surface. A model for cell surface UTI formation is proposed in which ITI binding to cells from serum used for the culture is followed by the limited proteolysis by trace amounts of active serine proteases, to form cell-surface receptor-bound UTI and the H-chains intercalated into cell surface HA. This process is subject to regulation of cell-associated UTI and of stabilization of pericellular matrix.