Scale-up of L-lactic acid production by mutant strain Rhizopus sp. MK-96-1196 from 0.003 m3 to 5 m3 in airlift bioreactors

In order to study the feasibility of commercial-scale L-lactic acid production by Rhizopus sp. MK-96-1196 using large scale airlift bioreactors (ALBs), a scale-up study from 0.003 m3 to 5 m3 ALB was carried out using oxygen transfer rate (OTR) as the scale-up criterion. Enhanced L-lactic acid production was achieved at OTRs higher than 0.28 (g-O2/l/h) irrespective of the scale of the bioreactor in question: in the range of 0.003 m3 to 5 m3, more than 90 g/lL-lactic acid was produced with a yield of approximately 80%, based on the initial glucose concentration. In future research, we plan to design an ALB greater than 3000 m3 (working volume: 2000 m3) for further studies on the production of L-lactic acid in large quantities.     

Criteria for versatile GaN MOVPE tool: high growth rate GaN by atmosphericpressure growth

Growth rate has a direct impact on the productivity of nitride LED production. Atmospheric pressure growth of GaN with a growth rate as high as 10 μm/h and also Al_0.1Ga_0.9N growth of 1 μm/h by using 4 inch by 11 production scale MOVPE are described. XRD of (002) and (102) direction was 200 arcsec and 250 arcsec, respectively. Impact of the growth rate on productivity is discussed.     

Differential effect of a PAF antagonist CV-3988 on active and passive anaphylactic shock in various mouse strains

To define the role of platelet-activating factor (PAF) in anaphylactic shock in the mouse, the suppressive effect of CV-3988, a PAF antagonist, on active and passive anaphylactic shock was studied. Various mouse strains treated or not treated withBordetella pertussis (B. pertussis) were used. We found that the effect of CV-3988 on anaphylactic shock in the mice that were actively sensitized with bovine serum albumin plusB. pertussis differed markedly according to mouse strain. CV-3988 suppressed the anaphylactic shock in C3H/He and CBA/JN mice at a low dose of 3 mg/kg, whereas antagonists to other mediators such as histamine, serotonin, thromboxane A₂ and leukotrienes did not show a suppressive effect. This suggests that PAF plays a major role in anaphylactic shock in these strains. On the other hand, CV-3988 did not suppress active anaphylactic shock in cataract Shionogi (CTS), NOD and DS strains even at a high dose of 30 mg/kg, which could be interpreted to suggest that PAF is not active in these strains. However, this possibility was ruled out based on the similar results obtained in passive anaphylactic shock and PAF-induced shock in these mice. Passive anaphylactic shock in CTS mice mediated by IgG₁ antibody was markedly suppressed by CV-3988 but not at all by antagonists to other mediators. Furthermore, the suppressive action of CV-3988 against passive anaphylactic shock, and PAF-induced shock was greatly attenuated when the mice were pretreated withB. pertussis. From these results, the conclusion can be drawn that PAF is the main mediator of active and passive anaphylactic shock in the mouse in general, even though the effect of CV-3988 differs depending on the mouse strain and on whether or notB. pertussis treatment is used. Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl Ether Lipids, Tokyo, Japan, May 1989.     

Impairment of peripheral nerve excitability

Functional abnormalities, especially the excitability changes of axon in the peripheral nerve involvement, were reviewed. In GBS and CIDP, the correlation between conduction block and anti-ganglioside antibodies have been discussed. Using anti GM1 antibody positive sera, the suppression of voltage-gated sodium channels (VGSC) has been reported. Although this findings have not been confirmed, the involvement of VGSC may be an important mechanism for eliciting conduction block. In Isaacs' syndrome, voltage-gated potassium channels (VGKC) were suppressed by autoantibodies to VGKC. Furthermore, in generalized myokymia syndrome which shows only myokymia and muscle cramp without grip myotonia, VGKCs are also suppressed in some cases. These findings suggest that some patients with myokymia and neuromyotonia are induced by anti-VGKC antibodies. For evaluating the axonal excitability in vivo, the threshold electrotonus method have been developed and applied for the involvement of peripheral nerves. In ALS, impairment of potassium conductance was shown and was speculated to have the possible rrelation with fasciculation. Thus threshold electrotonus method will be an important method for evaluating axonal excitability in human. The accumulated knowledge about the involvement of axonal ion channels will expand and will be categorized as axonal channelopathies.     

Hydrogen Embrittlement of a 1500-MPa Tensile Strength Level Steel with an Ultrafine Elongated Grain Structure

A deformation of a tempered martensitic structure (i.e., tempforming) at 773 K (500 °C) was applied to a 0.6 pct C-2 pct Si-1 pct Cr steel. The hydrogen embrittlement (HE) property of the tempformed (TF) steel was investigated by a slow strain rate test (SSRT) and an accelerated atmospheric corrosion test (AACT). Hydrogen content within the samples after SSRT and AACT was measured by thermal desorption spectrometry (TDS). The tempforming at 773 K (500 °C) using multipass caliber rolling with an accumulative are reduction of 76 pct resulted in the evolution of an ultrafine elongated grain (UFEG) structure with a strong 〈110〉//rolling direction (RD) fiber deformation texture and a dispersion of spheroidized cementite particles. The SSRT of the pre-hydrogen-charged notched specimens and the AACT demonstrated that the TF sample had superior potential for HE resistance to the conventional quenched and tempered (QT) sample at a tensile strength of 1500 MPa. The TDS analysis also indicated that the hydrogen might be mainly trapped by reversible trapping sites such as grain boundaries and dislocations in the TF sample, and the hydrogen trapping states of the TF sample were similar to those of the QT sample. The QT sample exhibited hydrogen-induced intergranular fracture along the boundaries of coarse prior-austenite grains. In contrast, the hydrogen-induced cracking occurred in association with the UFEG structure in the TF sample, leading to the higher HE resistance of the TF sample.     

PACAP colocalizes with luteinizing and follicle-stimulating hormone immunoreactivities in the anterior lobe of the pituitary gland

Pituitary adenylate cyclase activating polypeptide (PACAP) and its close relative vasoactive intestinal polypeptide (VIP) were demonstrated in the anterior pituitary gland. The cells which exhibited PACAP immunoreactivity were oval or round shaped. Their distribution was similar to that of gonadotropes but the number of PACAP immunoreactive cells was less. Double labeling revealed that PACAP immunoreactivity partially colocalized with luteinizing and follicle-stimulating hormone; however, colocalization with other pituitary hormone immunoreactivities was not demonstrated. Our results suggest an autocrine or paracrine role of PACAP in the regulation of pituitary functions.     

An EGF receptor-mediated signal attenuates the inhibitory effect of LPA on an adenylate cyclase activity

A tyrosine kinase receptor-mediated and a heterotrimeric G protein-coupled receptor-mediated signals have been shown to evoke distinct intracellular signaling events. There has been increasing evidence that cross-talk exists between a tyrosine kinase receptor-mediated and a heterotrimeric G protein-coupled receptor-mediated signal transduction pathways. In the present study, we have studied effects of EGF receptor activation on activities of inhibitory G protein (Gi). We show that the amounts of Gi/Go ADP-ribosylated by islet-activating protein (IAP) increased by 30-40% in the membranes of Rat 1 fibroblast cells pretreated with EGF compared with those without pretreatment. When an effect of lysophosphatidic acid (LPA) stimulation on an adenylate cyclase activity was examined, LPA partly attenuated forskolin-stimulated adenylate cyclase activity via Gi because IAP pretreatment blocked the inhibitory effect of LPA. Pretreatment with EGF reduced the ability of LPA to inhibit the forskolin-stimulated adenylate cyclase activity, while the pretreatment did not have any effects on the forskolin-stimulated activity. Thus, the EGF receptor-mediated signal appears to cause the impairment of Gi function in Rat 1 fibroblast cells.     

Clinical study on five myeloperoxidase specific anti-neutrophil cytoplasmic antibody (MPO-ANCA) positive Churg-Strauss syndrome cases

Human adrenal medullary chromaffin cells were prepared and cultured from a cystic tumoral adrenal gland whose medullary tissue was unaffected. Adrenaline-containing and noradrenaline-containing cells were identified using a confocal fluorescence microscope and antibodies against dopamine beta-hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT). Current/voltage (I/V) curves performed with the voltage-clamped cells bathed in 10 mM Ba2+ (holding potential, Vh=-80 mV) revealed the presence of only high-threshold voltage-dependent Ca2+ channels; T-type Ca2+ channels were not seen. By using supramaximal concentrations of selective Ca2+ channel blockers, the whole-cell IBa could be fractionated into various subcomponents. Thus, IBa had a 25% fraction sensitive to 1 microM nifedipine (L-type channels), 21% sensitive to 1 microM omega-conotoxin GVIA (N-type channels), and 60% sensitive to 2 microM omega-agatoxin IVA (P/Q-type channels). The activation of IBa was considerably slowed down, and the peak current was inhibited upon superfusion with 10 microM ATP. The slow activation and peak current blockade were reversed by strong depolarizing pre-pulses to +100 mV (facilitation). A drastic facilitation of IBa was also observed in voltage-clamped human chromaffin cell surrounded by other unclamped cells; in contrast, in voltage-clamped cells not immersed in a cell cluster, facilitation was scarce. So, facilitation of Ca2+ channels in a voltage-clamped cell seems to depend upon the exocytotic activity of neighbouring unclamped cells, which is markedly increased by Ba2+. It is concluded that human adrenal chromaffin cells mostly express P/Q-types of voltage-dependent Ca2+ channels (60%). L-Type channels and N-type channels are also expressed, but to a considerably minor extent (around 20% each). This dominance of P/Q-type channels in human chromaffin cells clearly contrasts with the relative proportion of each channel type expressed by chromaffin cells of five other animal species studied previously, where the P/Q-type channels accounted for 5-50%. The results also provide strong support for the hypothesis that Ca2+ channels of human chromaffin cells are regulated in an autocrine/paracrine fashion by materials co-secreted with the catecholamines, i.e. ATP and opiates.     

Simulation of hydrologic and geomorphic changes affecting a shrinking mire

The Kushiro Mire in subarctic Japan has significantly reduced in size because of the complex interaction of many processes, including snowmelt runoff, sediment transport and vegetation dynamics. This study uses a coupled integrated catchment‐based eco‐hydrology model with a mass transport process (NICE‐MASS) to investigate the influence of hydrologic and geomorphic changes on the Kushiro Mire. Coefficients of the sediment‐rating curve in the snowmelt runoff are very different from those in the snow‐free period. This empirical relation shall underestimate the observed suspended sediment (SS) concentration in the snowmelt period, indicating a difference in runoff mechanisms between the two periods and the necessity of a process‐based model. The simulation model reproduced well the spatial distribution of elevation aggradations by sediment deposits from rivers flowing into the mire. NICE‐MASS clarified that river channelization works carried out in the past resulted in groundwater degradation and drying phenomenon in the downstream area because of increased sedimentation and a decrease of seepage infiltration from the river to the aquifer. It is assumed that these hydrologic and geomorphic changes are closely related to the invasion of alder (Alnus japonica) into the mire. The occupation rate of alder is positively correlated with groundwater degradation relative to the ground surface. The model simulation derived by addition of this limiting factors related to submerged depth is important for prediction of vegetation succession when devising future policies for restoration of meandering river channels. Copyright © 2009 John Wiley & Sons, Ltd.     

Finding tree patterns consistent with positive and negative examples using queries

This paper is concerned with the problem of finding a hypothesis in consistent with given positive and negative examples. The hypothesis class consists of all sets of at most two tree patterns and represents the class of unions of at most two tree pattern languages. Especially, we consider the problem from the point of view of the consistency problem for . The consistency problem is a problem for deciding whether there exists a consistent hypothesis with given positive and negative examples within some fixed hypothesis space. Efficient solvability of that problem is closely related to the possibility of efficient machine learning or machine discovery. Unfortunately, however, the consistency problem is known to be NP-complete for many hypothesis spaces. In this paper, the problem for the class is also shown to be NP-complete. In order to overcome this computational hardness, we try to use additional information obtained by making queries. First, we give an algorithm that, using restricted subset queries, solves the consistency problem for in time polynomial in the total size of given positive and negative examples. Next, we show that each subset query made by the algorithm can be replaced by several membership queries under some condition on a set of function symbols. As a result, we have that the consistency problem for is solved in polynomial time using membership queries. This revised version was published online in June 2006 with corrections to the Cover Date.