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This study aimed to clarify factors related to confidence in future childbirth and infant care in regard to radiation exposure at 4 and 7 yr after the Fukushima Daiichi Nuclear Power Plant disaster. A survey was conducted on 310 female college students in Fukushima Prefecture, Japan, in December 2015, and readministered to 275 students in November 2018. The analysis included 309 patients from 2015 and 253 from 2018. The Fukushima Future Parents Attitude Measure was used to assess attitudes about future childbirth and infant care in regard to radiation exposure. The results indicated that attitudes toward future childbirth were significantly influenced by self-esteem (β= –0.22), advice about radiation (β= 0.19), concerns about radiation effects on a future partner (β= –0.18), and college-related stress (β= 0.20). Moreover, attitudes toward infant care were influenced by self-esteem (β= –0.22) and perception of the genetic risks of radiation (β= –0.17). Therefore, to improve confidence in future childbirth and infant care among female college students in Fukushima, it is important to enhance self-esteem, reduce college-related stress, and create an environment where female college students feel comfortable discussing radiation concerns with experts and each other.

A critical step toward understanding autism spectrum disorder (ASD) is to identify both genetic and environmental risk factors. A number of rare copy number variants (CNVs) have emerged as robust genetic risk factors for ASD, but not all CNV carriers exhibit ASD and the severity of ASD symptoms varies among CNV carriers. Although evidence exists that various environmental factors modulate symptomatic severity, the precise mechanisms by which these factors determine the ultimate severity of ASD are still poorly understood. Here, using a mouse heterozygous for Tbx1(a gene encoded in 22q11.2 CNV), we demonstrate that a genetically triggered neonatal phenotype in vocalization generates a negative environmental loop in pup–mother social communication. Wild-type pups used individually diverse sequences of simple and complicated call types, but heterozygous pups used individually invariable call sequences with less complicated call types. When played back, representative wild-type call sequences elicited maternal approach, but heterozygous call sequences were ineffective. When the representative wild-type call sequences were randomized, they were ineffective in eliciting vigorous maternal approach behavior. These data demonstrate that an ASD risk gene alters the neonatal call sequence of its carriers and this pup phenotype in turn diminishes maternal care through atypical social communication. Thus, an ASD risk gene induces, through atypical neonatal call sequences, less than optimal maternal care as a negative neonatal environmental factor.

To assess corticospinal tract involvement in patients with amyotrophic lateral sclerosis (ALS) by correlating diffusion tensor imaging (DTI) measures with intra- and extracranial central motor conduction time (CMCT) and clinical features of the patients.

Tracheostomy has been employed to release the airway obstruction at the glottic level and to prevent sudden death in patients with multiple system atrophy (MSA). However, sudden death is possible even after tracheostomy. Nocturnal polysomnography showed that the apnea–hypopnea index became higher after tracheostomy, and all tracheostomized patients had frequent central sleep apneas.

Fluorescence microscopy is generally used for the research of biology, medical sciences and other life science fields. Especially, recent advances in laser technologies and in optical engineering have made it possible to investigate the nanoscale mechanisms of physiological and molecular biological processes and thus to extend its application to pathological and clinical investigations in therapeutic sciences. Furthermore, quantitative measurements of the small molecules, ions and proteins participated into the processes in living tissues, in vivo and in vitro, its movements, and locations can be observed with these optical technologies. Among them, the confocal microscopy was firstly invented for the purpose of visualization of such small-scale observations by using proper fluorescent molecules together with laser beams. Although contrast and resolution are degraded by strong scattering of the tissue preparations in the wide field conventional fluorescence microscope, the development of the confocal microscope can overcome some of the effects of scattering, since the detector pinhole rejects fluorescence from off-focus locations

Following a combinatorial library approach, 60 organic salts have been prepared by reacting 5 bile acids and 12 secondary amines. Gelation tests with various organic and aqueous solvents reveal that 16 salts are supramolecular gelators of which 6 salts are found to be ambidextrous displaying the ability to form gels with organic as well as aqueous solvents. The salt didodecylammonium cholate (1a7b) is the most versatile gelator, displaying gelation ability with a maximum number of solvents. AFM images of the xerogels of 1a7b in organic and aqueous solvents reveal the presence of fibrous aggregate including helical fibers. Dynamic and morphological behaviors of the aggregates in the gel state have been probed by dynamic light scattering (DLS) and small-angle neutron scattering (SANS) experiments on an aqueous gel (1:1 DMSO/H2O) of 1a7b. It is revealed that the gelation takes place via the formation of flexible fibrous clusters followed by physical cross-linking. DLS and SANS results also disclose that (1) the fibrous network is formed via flexible clusters of a few tens of nanometers in length, followed by immobile network formation; (2) the network structure is self-similar irrespective of gelator concentration, C, while the gelation temperature is C dependent; and (3) the fibrous aggregates are in the solid state with a sharp boundary.

The structure and dynamics of poly(N-isopropylacrylamide) (PNIPA)−clay nanocomposite (NC) gels have been investigated by small-angle neutron scattering and dynamic light scattering in order to account for their high strength and high deformability. The structure of clay dispersion in water was an assembly of clay platelets 300 Å in diameter and 10 Å thick. The structure factors of the clay dispersions were reduced to a master curve by normalizing with the clay concentration, Cclay, even across its sol−gel transition. On the other hand, the structure factors of the NC gels cannot be represented with a simple addition of the structure factors of the components, but with a sum of Lorentz (L) and squared-Lorentz (SL) functions. It was found that the SL term, indicating the gel inhomogeneities, becomes dominant by increasing Cclay. The chain dynamics of the gels was found to be similar to the conventional PNIPA gels chemically cross-linked with bis-acrylamide.

Effects of pressure on the phase separation and structure of weakly charged poly(N-isopropylacrylamide-co-acrylic acid) (PNIPA−AAc) solutions and gels with 7 wt % were investigated by small-angle neutron scattering (SANS). The phase diagrams were determined in the pressure−temperature (P−T) plane for the solution and gel with a light scattering method, which were parabolic functions, having maxima at (P = 38.1 MPa, T = 37.1 °C; for the solution) and (121.6 MPa, 51.6 °C; for the gel). SANS experiments were carried out according to the P−T phase diagrams. At the low temperature and pressure region, where the systems were in one phase, the scattering intensity functions, I(q)s, were well described with an Ornstein−Zernike function. However, a scattering maximum appeared in I(q)s at elevated temperatures and pressures. The regions where a scattering maximum was observed at T = 45 °C were P < 70 MPa and 200 MPa < P for the gel and P < 70 MPa for the solution. This scattering maximum is due to microphase separation as a result of antagonism between the electrostatic and hydrophobic interactions. In the case of the solution, an upturn in I(q) at the low q region was observed, indicating occurrence of macrophase separation in addition to microphase separation. For the polymer gels, on the other hand, such an upturn in I(q) was not observed as a result of pinning effect of cross-links. The phase behavior and critical phenomena of PNIPA−AAc gels and solutions will be discussed from the viewpoint of pressure effects on the hydrophobic interaction.

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The dynamic aspect of double network (DN) gels showing an extremely high mechanical strength has been investigated by dynamic light scattering (DLS) measurements. The DN gels are formed from highly cross-linked poly(2-acrylamido-2-methylpropanesulfonic acid) (PAMPS) as the first network and loosely cross-linked (or non-cross-linked) polyacrylamide (PAAm) as the second network. The results of DLS show that the presence of slow mode besides the gel mode (fast mode) enhances the strength of DN gels at the low cross-linking density of the second network. The dynamics of the slow mode cannot be explained in terms of reptational motion of the second component in the first network, but it is similar to the translational motion of PAAm polymers in a semidilute solution. A strong velocity dependence of the mechanical strength is observed at a shear rate close to the inverse of the relaxation time of the slow mode. These results suggest that large “voids” of the first network may exist, and PAAm polymers that exist in “voids” act as a “molecular crack stopper” in DN gels, keeping the crack from growing to a macroscopic level.

Pressure-induced phase separation of poly(N-isopropylacrylamide) (PNIPA) aqueous solutions and gels were investigated by small-angle neutron scattering (SANS). The cloud point curves were constructed on the pressure−temperature (P−T) plane by visual observation for both the solutions and gels. As observed in the phase diagram of aqueous solutions of proteins, the cloud point temperatures (Tcloud) were a function of the pressure, P, and had maxima at P0 = 51.7 MPa and P0 = 93.2 MPa respectively for the solution and gel in H2O. The difference in Tcloud indicates that the effect of cross-linking is significant, and it leads to an increase of the miscible region. The SANS intensity function for the solution was well represented by a Lorentz function, i.e., an Ornstein−Zernike (OZ) function, from which the correlation length, ξ, and the susceptibility, I(0), were evaluated as a function of pressure. The critical exponents were obtained to be 1.1 ≤ γp ≤ 1.23 and 0.5 ≤ νp ≤ 0.6, for the solution, similar to the case of the temperature dependence of ξ and I(0). The spinodal temperature, Tsp, seems to merge with the binodal curve (Tclould) at P0 for the PNIPA solution. I(q)'s for the gels, on the other hand, deviated significantly from an OZ form by approaching the spinodal and were well fitted with a sum of squared-Lorentz and Lorentz functions. This squared-Lorentz function accounts for the emergence of cross-link inhomogeneities, which become dominant near the spinodal. These structure changes by pressure will be discussed in conjunction with cold denaturation of proteins.

Stimuli-responsive diblock copolymers with a thermosensitive segment and a hydrophilic segment have been synthesized via sequential living cationic copolymerization, which involves a poly(vinyl ether) with oxyethylene pendants exhibiting LCST-type phase separation in water and a poly(hydroxyethyl vinyl ether) segment. Highly sensitive and reversible thermally induced micelle formation and/or physical gelation were observed with such diblock copolymers. For example, the flow behavior of an aqueous solution of a diblock copolymer varied from Newtonian to non-Newtonian and plastic flow within a very narrow temperature range. TEM and SANS studies showed that the observed change in viscosity was due to the formation of a macrolattice with body-centered-cubic symmetry of spherical micelles in aqueous solution. The critical temperature of micelle formation and/or physical gelation could be varied by altering the combination of two segments in the diblock copolymer. On the basis of these results, several systems incorporating various patterns of physical gelation behavior have been developed, and a strategy for constructing stimuli-responsive systems with block copolymers was established.

Background & Aims: The physiologic significance of the M"3 muscarinic receptor is unclear due to an absence of specific ligand. In the present study, M"3 receptor knockout (KO) mice were used to elucidate the role of M"3 receptors in gastric acid secretion and gastric mucosal integrity. Methods: M"3 KO versus wild-type mice aged 1 month to 2 years were included. Gastric acid secretion was assessed by both direct intragastric pH measurement and pylorus ligation. Serum gastrin and gastric mucosal histamine levels were determined by radioimmunoassay and enzyme-linked immunosorbent assay, respectively. Morphologic analysis was performed by both immunohistochemistry and transmission electron microscopy. Results: Fasted M"3 KO mice exhibited higher intragastric pH, lower acid output after pylorus ligation, a lower proportion of active parietal cells, and higher serum gastrin levels than fasted wild-type mice. Acid secretion in response to carbachol, histamine, gastrin 17, and 2-deoxy-d-glucose was impaired in the mutant mice. Although carbachol was still able to cause ~30% acid output in M"3 KO mice, the acid secretion was inhibited by pirenzepine or famotidine. Despite remarkable hypergastrinemia in M"3 KO mice, there were no trophic responses in the oxyntic mucosa with respect to the mucosal thickness, proliferation rate, and numbers of parietal and enterochromaffin-like cells. Cholecystokinin type 2 receptor antagonist YM022 was without the effect in M"3 KO mice. Conclusions:The present study shows that M"3 receptors are essential for basal acid secretion, a fully acid secretory response to histamine and gastrin, and the trophic responses of oxyntic mucosa to gastrin.

The dynamic aspects of the thermoreversible morphological transition of poly(2-ethoxyethyl vinyl ether)-b-poly(2-hydroxyethyl vinyl ether) (PEOVE-b-PHOVE) in aqueous solutions have been investigated by dynamic light scattering (DLS) and rheological measurements. A sample-position-dependent DLS study, employed here, allowed us to resolve two transitions, i.e., (1) molecular dispersion-to-micelle transition and (2) micelle-to-macrolattice transition, which were not clearly resolved by small-angle neutron scattering studies in the previous work. These transitions are characterized by (1) an abrupt increase in the scattered intensity and (2) an appearance of speckle patterns. The temperature where the abrupt increase in intensity was observed was a few degrees lower than that the speckle pattern appeared. Rheological behaviors also supported the two transitions as (1) Newtonian-to-non-Newtonian transition and (2) non-Newtonian-to-plastic flow transition. It is concluded that a pseudo-sol-to-gel transition without chain anchoring is enough for an ergodic-to-nonergodic transition.

Because of the high global warming potential of SF₆ gas, research on alternative gases for electrical insulation with a lower environmental impact is essential. Gas mixtures composed of electronegative gases and N₂ gas have the advantage of the reduction of the amount of SF₆ gas and of utilizing the synergistic effect in electrical insulation performance. We investigated the partial discharge (PD) and breakdown (BD) characteristics of SF₆/N₂ and PFC (C₃F₈/N₂ and C₂F₆/N₂) gas mixtures under non-uniform electric field conditions, by changing the dilute content of electronegative gases. As a result, the synergistic effect in SF₆/N₂ gas mixtures was verified to be higher than that in PFC/N₂ gas mixtures. The physical mechanism from PD inception to BD was discussed with consideration of the difference in electronegativity of SF₆ and PFC gases. Furthermore, we found that PD inception and PD-to-BD mechanisms changed at a content of 10 ppm for SF₆ due to the electron attachment activity of SF₆ gas. The change in the PD and BD mechanisms in C₃F₈/N₂ and C₂F₆/N₂ gas mixtures appeared at 0.1&percent; content for C₃F₈ and at 1&percent; content for C₂F₆.

The sharp and thermoreversible morphological transitions of poly(2-ethoxyethyl vinyl ether-b-2-hydroxyethyl vinyl ether) (poly(EOVE-b-HOVE)) in aqueous solutions have been investigated by means of small-angle neutron scattering. The poly(EOVE-b-HOVE), synthesized by living cationic polymerization, had the number-average degree of polymerizations of the constituent blocks of 200 and 400, respectively, and a polydispersity index of 1.07. The poly(EOVE-b-HOVE) underwent a disorder−order transition around 17−21 °C, depending on the polymer concentration. This is a micellization with a poly(EOVE) core of ca. 20 nm in radius and a poly(HOVE) corona. When the polymer concentration was high enough, e.g., 17 wt %, a macrolattice formation with body-centered cubic symmetry was also observed. This transition took place in a narrow temperature window of less than a degree centigrade. The origin of this sharp transition was found to be a dissociation of hydrophobically associated structure, such as an iceberg structure. The enthalpy involved in this dissociation was estimated to be 2.05 kcal/mol of an EOVE monomeric unit, which is about twice as large as that of a well-known thermosensitive polymeric system, i.e., poly(N-isopropylacrlyamide) aqueous solutions.

Abstract:: The structure of Be and C isotopes are investigated based on the molecular-orbit (MO) model. The low-lying states are characterized by several configurations of valence neutrons, which are constructed as combinations of basic orbits. In 10Be, all of the observed positive-parity bands and the negative-parity bands are described within the model. The second 0+ state of 10Be has a large α-α cluster structure, and this is characterized by a (1/2+σ)2 configuration. An enlargement of the α-α distance due to two-valence neutrons along the α-α axis makes their wave function smooth and reduces the kinetic energy drastically. Furthermore, the contribution of the spin-orbit interaction due to coupling between the S z = 0 and the S z = 1 configurations, is important. In the ground state of 12Be, the calculated energy exhibits similar characteristics, that the remarkable α clustering and the contribution of the spin-orbit interaction make the binding of the state with (3/2-π)2(1/2+σ)2 configuration properly stronger in comparison with the closed p-shell (3/2-π)2(1/2-π)2 configuration. This is related to the breaking of the N = 8 (closed p-shell) neutron magic number. Also, the molecule-like structure of the C isotopes is investigated using a microscopic α+α+α+n+n+ . . . model. The combination of the valence neutrons in the π- and the σ-orbit is promising to stabilize the linear-chain state against the breathing and bending modes, and it is found that the excited states of 16C are the most promising candidates for such structure.

Background & Aims:: Histamine, gastrin, and acetylcholine are known to be the primary secretagogues of gastric acid secretion, but how the roles are shared among these secretagogues remains to be fully clarified. To evaluate the cooperation between histamine and the other secretagogues, acid secretion responses induced by each secretagogue were measured in L-histidine decarboxylase (HDC)-deficient mice. Methods:: Acid secretion was measured by the titration of acid under anesthesia. The expression of selected genes involved in acid secretion was determined by Northern blot and/or immunoblot analysis. Histamine-2 (H"2) receptor binding in the gastric mucosa was investigated using [^3H]tiotidine. Results:: HDC-deficient mice showed low basal and high exogenous histamine-stimulated acid secretion. The mutant mice showed hypergastrinemia and did not undergo acid secretion upon treatment with exogenous gastrin. However, carbachol stimulated weak and transient acid secretion in the mutants. The Bmax values for H"2 and the expression of Gs@a in gastric mucosal membranes were higher in the mutants than in the wild-type mice. Conclusions:: This study confirms the concept that histamine production is essential for gastric acid secretion induced by gastrin, but not for that induced by carbachol. HDC-deficient mice should be a suitable model for further functional analyses of the correlation between histamine and the other acid secretagogues.

Abstract: Background. To control advanced cervical squamous cell carcinoma more effectively and more easily, we used neoadjuvant chemotherapy, with three drugs carboplatin, ifosfamide, and peplomycin (PIP), in a study performed from July 1990 to October 1994 in nine Institutions. Methods. Sixty-five patients with untreated, inoperable squamous cell carcinoma of the cervix were treated with carboplatin (300 mg/m2 IV; low-dose PIP regimen, or 400 mg/m2 IV; high-dose PIP regimen) on day 1, ifosfamide (1000 mg/m2, IV) on days 1–3, and peplomycin (5 mg/body, IM) on days 1–6. The low-dose PIP was given between July 1990 and April 1992, and the high-dose PIP from May 1992 to October 1994. Results. Response rates for the low- and high-dose PIP regimens were 42.9% (12/28) and 59.5% (22/37), respectively. Measurable lesions were recognized in the cervix, pelvic lymph node (PeN), paraaortic lymph node (PAN), lung, and supraclavicular lymph node. Response rates in these individual lesions to our low- and high-dose PIP regimens were 35.7% (10/28) and 55.6% (20/36), respectively in the cervical lesion and more than 50% for both regimens in the PeN and PAN metastatic lesions, while the supraclavicular lymph node metastatic lesions responded poorly to both regimens. After low-dose PIP, surgery was performed in 2 patients (2/28; 7.1%), while after high-dose PIP, 12 patients (12/37; 32.4%) underwent surgery. The 3-year survival rate of patients with high-dose PIP was significantly higher than that of those with low-dose PIP (P < 0.01). Conclusions. Neoadjuvant chemotherapy with PIP appears feasible and effective. The link between dosage and treatment response and achievable surgery rate and survival rates suggests that results might be further optimized by considering patients' renal function, and utilizing the Calvert formula for dosing analysis.

The effects of an amino acid, L-glutamine, on aspirin-induced gastric lesions and gastric secretion were studied in either intact or pylorus-ligated rats. L-Glutamine had a pronounced inhibitory effect on gastric lesions induced by aspirin administered by oral, intraperitoneal, or intraduodenal routes to intact or pylorus-ligated rats. By the oral route the inhibition was dose-related. However, L-glutamine given either intraduodenally or intraperitoneally did not show any appreciable effects on gastric lesions induced by orally administered aspirin in pylorus-ligated rats. One mechanism of L-glutamine protection was inhibition of a back diffusion of gastric acid caused by aspirin and this was demonstrated in pylorus-ligated rats. The reduction in H+and increase in Na+concentrations in the lumen caused by aspirin was returned to normal by increasing doses of L-glutamine. In addition, L-glutamine was considered to inhibit the back diffusion of acid caused by pylorus ligation per se, because the amino-acid produced an increment of H+and reduction of Na+and K+in comparison with the control group. The role of pepsin on L-glutamine protection was negligible.

We have cloned the gene NPS1 (nuclear protein of Saccharomyces) which encodes a nuclear protein of mol. wt 156 735 Daltons (1359 amino acids) essential for cell growth. NPS1 contains a 2 kb sequence that is highly homologous to the S. cerevisiae SNF2/GAM1 gene known as a transcriptional regulator for multiple genes. However, the NPS1 gene was found to have a distinct function from SNF2/GAM1. The growth of the cells carrying a nps1 delta :: URA3 deletion allele and galactose‐inducible NPS1 on a plasmid was arrested under NPS1‐repressed conditions with a cell cycle arrest phenotype, being arrested at the large‐bud stage with a single nucleus that had a DNA content of G2/M phase. When the arrested cells were further incubated under NPS1‐repressed conditions, re‐replication of DNA occurred in some of the arrested cells without passage through mitosis. In the predicted amino acid sequence of NPS1, sequences homologous to the catalytic domain of protein kinases were found. We constructed a mutation which results in the substitution of a highly conserved lysine residue (Lys792) in the presumed ATP‐binding site of this kinase‐like domain with a glutamic acid codon. The mutant gene failed to rescue the growth defect caused by NPS1 disruption, suggesting that Lys792 is essential for the function of NPS1.

Microtubule bundles reminiscent of those found in neuronal processes are formed in fibroblasts and Sf9 cells that are transfected with the microtubule-associated proteins tau, MAP2, or MAP2c. To analyze the assembly process of these bundles and its relation to the microtubule polarity, we depolymerized the bundles formed in MAP2c-transfected COS cells using nocodazole, and observed the process of assembly of microtubule bundles after removal of the drug in cells microinjected with rhodamine-labeled tubulin. Within minutes of its removal, numerous short microtubule fragments were observed throughout the cytoplasm. These short fragments were randomly oriented and were already bundled. Somewhat longer, but still short bundles, were then found in the peripheral cytoplasm. These bundles became the primordium of the larger bundles, and gradually grew in length and width. The polarity orientation of microtubules in the reformed bundle as determined by "hook" procedure using electron microscope was uniform with the plus end distal to the cell nucleus. The results suggest that some mechanism(s) exists to orient the polarity of microtubules, which are not in direct continuity with the centrosome, during the formation of large bundles. The observed process presents a useful model system for studying the organization of microtubules that are not directly associated with the centrosomes, such as those observed in axons.

The gastric mucosa responds to taurocholate (TC) by significantly decreasing acid secretion. We examined the role of nitric oxide (NO) in this phenomenon in comparison with endogenous prostaglandins. A rat stomach was mounted in an ex-vivo chamber and perfused with saline, and the potential difference, luminal pH and acid responses were measured before and after the application of 20 mM TC for 30 min with or without pretreatment with the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) or the cyclooxygenase inhibitor indomethacin. Exposure of the stomach to TC caused a reduction in potential difference, a decrease in acid secretion and an increase in luminal HCO3-. Pretreatment with L-NAME or indomethacin did not affect potential difference and HCO3- responses, but it significantly attenuated the decrease in acid secretion caused by TC. The effect of L-NAME was more potent than that of indomethacin, and, especially in the presence of L-NAME, acid secretion was actually enhanced after exposure to TC. Aminoguanidine, the selective inhibitor of inducible NO synthase, did not have any significant effect on either parameter. This effect of L-NAME was antagonized by the simultaneous administration of L-arginine but not by that of D-arginine, whereas the effect of indomethacin was reversed by PGE2. Acid secretion in normal stomachs was significantly reduced by nitroprusside and PGE2 but was not affected by either L-NAME or indomethacin.(ABSTRACT TRUNCATED AT 250 WORDS)

The present study was undertaken to investigate the possible mechanism of histamine cytoprotection against 0.6 N HCl-induced gastric lesions in rats by 1) examining functional alterations such as acid secretion, gastric motor activity and mucosal vascular permeability in response to histamine and by 2) comparing the effects of histamine with those of 2-(2-pyridil)-ethylamine (PEA), an H1-agonist and of dimaprit, an H2-agonist. Histamine (3-20 mg/kg s.c.) dose-dependently increased acid secretion, inhibited motor activity and reduced the mucosal lesions in response to 0.6 N HCl. Similar effects were observed dose-dependently with dimaprit (10-40 mg/kg s.c.), but not with PEA (10 mg/kg s.c.). The protective action of both histamine and dimaprit was attenuated significantly by cimetidine (100 mg/kg s.c.) and indomethacin (5 mg/kg s.c.), but not by tripelennamine (10 mg/kg s.c.), which by itself inhibited significantly motor activity and the lesions. Stimulation of acid secretion caused by histamine as well as dimaprit was antagonized significantly by cimetidine, whereas antigastric motor effects of these agents were decreased significantly by both cimetidine and indomethacin. Histamine and PEA increased significantly the vascular permeability as measured by Evans blue, but the increased vascular permeability caused by 0.6 N HCl was reduced markedly by both histamine and dimaprit. These results suggest that the mucosal protective action of histamine may be mediated at least partly by endogenous prostaglandins through stimulation of H2-receptors, and may be associated with the effect on gastric motor activity but not with that on the mucosal vasculature.

We previously documented differences in the behavior of microtubules in growing axons of two types of neurons, adult mouse sensory neurons and Xenopus embryonal spinal cord neurons. Namely, the bulk of microtubules was stationary in mouse sensory neurons both by the method of photoactivation of caged-fluorescein-labeled tubulin and photobleaching of fluorescein-labeled tubulin, but the bulk of microtubules did translocate anterogradely by the method of photoactivation. Although these results indicated that the stationary nature of photobleached microtubules in mouse neurons is not an artifact derived from the high levels of energy required for the procedure, it has not yet been settled whether the photobleaching method can detect the movement of microtubules properly. Here we report photobleaching experiments on growing axons of Xenopus embryonal neurons. Anterograde movement of photobleached microtubules was observed at a frequency and translocation rate similar to the values determined by the method of photoactivation. Our results suggest that, under appropriate conditions, the photobleaching method is able to reveal the behavior of microtubules as accurately as the photoactivation method.

Thewaxy proteins encoded by the genomes A, B, and D in polyploid wheats and related diploid species were isolated by SDS-PAGE. The N-terminal amino acid sequences of mature proteins and V8 protease-induced fragments were determined. A total of five amino acid substitutions was detected in these sequences, which represent about 10% of the whole sequences of thewaxy proteins. A comparison of these sequences in polyploid wheats with those in related diploid species revealed the following: (i)waxy proteins encoded by the A genome of polyploid wheats were identical to that ofTriticum monococcum, (ii) thewaxy protein encoded by the B genome ofT. turgidum was identical to that ofT. searsii, but differed from those ofT. speltoides andT. longissimum by one amino acid substitution, (iii) thewaxy protein encoded by the B genome ofT. aestivum differed from that encoded by the B genome ofT. turgidum by one amino acid substitution, and (iv) thewaxy protein encoded by the D genome ofT. aestivum was identical to that ofT. tauschii.

The molecular weights ofwaxy proteins, by SDS-PAGE, and the N-terminal amino acid sequences of mature protein and of V8 protease-induced fragments were determined in diploid cereals. The homology of the primary structure was relatively high among cereals examined here, and there appeared to be a common sequence, V-F-V-G-A-E-M-A, in the vicinity of the N terminus. Based on the amino acid sequences, these cereals could be divided into two groups, including corn and rice in one and diploid wheat, fourAegilops species, rye, and barley in the other. In diploid wheat andAegilops species there were substitutions of amino acids in the primary structure. Variations of this sort suggest that the primary structure ofwaxy proteins would provide clues to the phylogenetic relations in the wheat group.

To study microtubule (MT) dynamics in nerve cells, we microinjected biotin-labeled tubulin into the cell body of chemically fused and differentiated PC12 cells and performed the immunofluorescence or immunogold procedure using an anti-biotin antibody followed by secondary antibodies coupled to fluorescent dye or colloidal gold. Incorporation of labeled subunits into the cytoskeleton of neurites was observed within minutes after microinjection. Serial electron microscopic reconstruction revealed that existing MTs in PC12 neurites incorporated labeled subunits mainly at their distal ends and the elongation rate of labeled segments was estimated to be less than 0.3 micron/min. Overall organization of MTs in the nerve cells was different from that in undifferentiated cells such as fibroblasts. Namely, we have not identified any MT-organizing centers from which labeled MTs are emanating in the cell bodies of the injected cells. Stereo electron microscopy revealed that some fully labeled segments seemed to start in the close vicinity of electron dense material within the neurites. This suggests new nucleation off some structures in the neurites. We have also studied the overall pattern of the incorporation of labeled subunits which extended progressively from the proximal part of the neurites toward their tips. To characterize the mechanism of tubulin incorporation, we have measured mean density of gold labeling per unit length of labeled segments at different parts of the neurites. The results indicate access of free tubulin subunits into the neurites and local incorporation into the neurite cytoskeleton. Our results lead to the conclusion that MTs are not static polymers but dynamic structures that continue to elongate even within the differentiated nerve cell processes.

This paper treats a method of calculating natural frequency of vibratory feeders. In a bowl-type feeder, the deformation of the spring is complicated and the exact calculation of its constant is difficult. Therefore an approximate calculation is presented under some assumptions. The relations between spring constant and spring setting condition are clarified and shown in various diagrams. The equations of natural frequency for the fixed type and the semi-floating type feeder are represented briefly. The vibration direction of bowl-type feeder is also discussed. The theoretical results are confirmed by experimental studies.

We examined whether a single inoculation of Helicobacter pylorican colonize the stomachs of ulcerated rats and delay their healing and whether an antibiotic drug and acid pump inhibitors can enhance the ulcer healing in infected rats. Ulcers were produced by a submucosal injection of acetic acid solution into the gastric wall. Helicobacter pylori(ATCC‐43504) was inoculated into rats with and without gastric ulcers. The animals were killed 2, 4, 6, 8 or 10 weeks after the inoculation and the ulcerated area and H. pyloriviability were determined. Each test drug and their combination was administered for 1 or 2 weeks after H. pyloriinoculation. Helicobacter pyloricould not colonize the stomachs of normal rats, but could colonize stomachs with ulcers for 10 weeks at an incidence of > 80%. Spontaneous healing of gastric ulcers was delayed by H. pyloriinfection during these 10 weeks. Daily treatment with clarithromycin significantly and dose‐dependently delayed ulcer healing in infected rats. Both omeprazole and leminoprazole significantly enhanced ulcer healing and inhibited the clarithromycin‐delayed ulcer healing. We conclude that: (i) H. pylorican colonize rat stomachs with ulcers and delay ulcer healing; (ii) clarithromycin delays ulcer healing in H. pylori‐infected rats; and (iii) acid pump inhibitors inhibited the clarithromycin‐delayed ulcer healing.

Effects of carbenoxolone Na on acute or chronic types of gastric lesions or ulcer models produced in rats, guinea pigs, or dogs were studied. Carbenoxolone Na, given either orally or intraperitoneally, produced a significant inhibition of stress-induced gastric lesions in intact or in pylorus-ligated rats. Acetylsalicylic acid (ASA)-induced or serotonin-induced gastric lesions in rats were also inhibited significantly by pretreatment with the drug. However, carbenoxolone Na did not affect the development of Shay ulceration in rats even though the peptic activity in gastric juices was markedly reduced by the drug. Histamine-induced gastric lesions in guinea pigs were not prevented by pretreatment with carbenoxolone Na. Although carbenoxolone Na, given for 10–20 days, did not promote the healing of stress-induced gastric lesions and acetic acid gastric ulcers in rats, it significantly accelerated the healing of chronic gastric ulcer produced in dogs by 3 weeks' treatment. Carbenoxolone Na prevented the acid back-diffusion caused by ASA without any influence on Na+ efflux in pylorus-ligated rats.

This paper treats the motion of a particle on a vibratory feeder whose track has directional characteristic in repulsive motion, for examples, obliquely bristled track, obliquely sliced track and so on. Under some assumptions, the practical equation for predicting the mean conveying velocity is shown and the relations between conveying condition and the mean conveying velocity are clarified theoretically. These relations are shown in various diagrams. Referring these diagrams, the optimum conveying conditions are discussed also. The theoretical results show that the mean conveying velocity is considerably larger than that of the ordinary feeder. The theoretical results are confirmed by experimental studies.

To understand the mechanism of the sequential restriction of multipotency of stem cells during development, we have established culture conditions that allow the differentiation of neuroepithelial precursor cells from embryonic stem (ES) cells. A highly enriched population of neuroepithelial precursor cells derived from ES cells proliferates in the presence of basic fibroblast growth factor (bFGF). These cells differentiate into both neurons and glia following withdrawal of bFGF. By further differentiating the cells in serum-containing medium, the neurons express a wide variety of neuron-specific genes and generate both excitatory and inhibitory synaptic connections. The expression pattern of position-specific neural markers suggests the presence of a variety of central nervous system (CNS) neuronal cell types. These findings indicate that neuronal precursor cells can be isolated from ES cells and that these cells can efficiently differentiate into functional post-mitotic neurons of diverse CNS structures.