Recently exfoliated ultrathin sheets from layered inorganic materials have attracted extensive attention because of their application to thin film-type electronic devices and sensors. The main advantage using these sheets of this approach is to deposit semiconducting films using solution processes at room temperature with no ultra-vacuum technique. Among a variety of layered inorganic compounds, we found that smectite clay minerals are an excellent candidate because of their abundance in nature and kindness for the environment. For these reasons, we prepared a cast film of exfoliated clay and studied its electronic conduction through the hetero-interface formed by two kinds of inorganic nanosheets.

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Casein kinase 2(CK2) is a highly pleiotopic Ser/Thr protein kinase. Genetic, biochemical, and cell biological studies have indicated the involvement of this enzyme in the control of cell proliferation and in signal transduction. CK2 has long been considered a constitutively non-regulated kinase. However, we have shown that CK2 activation occurred during cell cycle progression in response to growth stimuli of G0-arrested human normal fibroblasts. As the downstream target for CK2, we find that eukaryotic translation initiation factor eIF5 is phosphorylated at Ser 389 and Ser390. Results obtained by the expression of eIF5 mutants that lack CK2 phosphorylation sites suggest that CK2 may be involved in the regulation of cell cycle progression through the phosphorylation of a key molecule for translation.

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Hypoxia is a hallmark of malignant tumors. Although more than half a century has passed since it was suggested that tumor hypoxia caused bad treatment outcomes and contributed to the recurrence of tumors, no fundamental solution to this problem has been found yet. Since the hypoxia-inducible transcription factor HIF-1 was reported in 1992, research on hypoxic tumor cells has progressed with increasing speed, and it was found that the function of various genes, the expression of which is induced in hypoxic tumor cells by HIF-1, is strongly associated with the malignant alteration of the whole tumor. Therefore, HIF-1-active hypoxic cells in solid tumors are extremely important therapeutic targets of cancer therapy, particularly in the therapy of refractory cancers. Furthermore, HIF-1-active cells are considered crucial to obtain information on the hypoxic fraction of solid tumors, and to conduct therapies that act specifically at these cells for achieving a greater anticancer effect and preventing the recurrence and malignant alteration of cancers. We have been developing PTD-ODD fusion proteins, which are specific to HIF-1-active tumor cells, to target and image them for treating and diagnosing the malignant tumors, respectively.

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Cortical field potentials were recorded by cortical surface and depth electrodes implanted in various cerebral cortices in monkeys during self-paced simple movements of hand, mouth, neck and trunk, and complex movements of neck and trunk. The potentials were also recorded while the monkeys learned simple visuo-, audio- and somatosenso-initiated hand movements, and complex visuo-, audio- and somatosenso-initiated hand movements with discrimination of color, tone and texture etc. The potentials were analyzed in connection with cognitive functions. It was revealed in which cortical area any cognitive function was mainly localized in the frontal and parietal lobes. Motor and spatial discrimination functions were found to be disturbed by cerebellar hemispherectomy. After cerebellar hemispherectomy, substitute motor functions for the somatosensory and posterior parietal cortices of lowered motor functions of the motor cortex appeared, and increase of the substitute functions was discussed in connection with rehabilitation therapy of physical exercise etc.
Effects of physical exercise on cognitive functions were further studied using eight monkeys. Two of them were trained for 3-7 months with a newly developed machine for monkey hindlimb movement (exercise group). While the monkeys in the exercise group learned simple audio- and visuo-initiated hand movements after the physical exercise, cortical field potentials and reaction times were recorded and then analyzed. The analyzed results were compared with those in six monkeys without the physical exercise (no-exercise group). It was suggested that physical exercise improved cognitive functions in monkeys.

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Although articular cartilage is an avascular tissue, accumulating evidence suggests that angiogenesis and angiogenesis-related factors such as vascular endothelial growth factor (VEGF) could be involved in the pathophysiology of arthritis. Expression of the angiogenic factors are known to be regulated by hypoxic stimuli, thus indicating a hypoxia-angiogenesis axis occurring in the inflammatory joint milieu which might lead to cartilage destruction. Further investigations may open an avenue to establish a novel strategy against arthritis, by targeting the angiogenic process in articular cartilage.

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ErbB receptors, a kind of subfamily of receptor-type tyrosine kinase, are receptors for epidermal growth factor (EGF) and neuregulin (NRG) a neurotrophic factor, which play multifunctional roles in the development of nervous systems and the acquisition of higher-order functions. The ErbB/NRG signaling regulates the activity of ion channels and neurotransmitter receptors in synapses, and its dysfunction causes neurodegenerative and mental disorders (particularly schizophrenia). To know the regulation mechanism of ErbB signaling on participation of membrane composition, we examined the role of microdomains “lipid rafts” in primary cultured neurons. We separated the lipid raft membrane fractions, and examined lipid and protein compositions under the condition of low (5mM) and high (30mM) KCl concentrations in cerebellar granule cells. The dynamics of lipid composition and synaptic proteins changed according to concentrations of KCl. In high KCl treatment, phosphatidylcholine (PC) with saturated fatty acids was characteristically increased and PC species containing polyunsaturated fatty acids was decreased. ErbB2, B4 proteins were shifted to the raft fractions. Low KCl and depletion of cholesterol/sphingolipid led to loss of synapse-like structure. The remaining punctuated signals became greatly enlarged. As other proteins, NMDAR, NR1 and PSD95/93 protein distribution changed by different KCl concentrations. Our findings demonstrate a critical role for lipid rafts in NRG signaling and modulation of synaptic plasticity in the central nervous system.

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The present study is part of a design proposal for signposts on the Tokyo Metropolitan expressway. Legibility and recognizability of candidate fonts of full-scale signposts were measured. The fonts used were Shin Go M and VialogLT M. Thirty-two participants read Japanese, alphabetic and alphanumeric nonsense syllables whose sizes changed in 5 steps; for Japanese syllables, 500, 450, 400, 350, and 300 mm, for alphabetic and alphanumeric syllables, 400, 350, 300, 250 and 200 mm. Two types of distance were measured. For legibility, the participants had to stop when they thought they could read the word. For recognizability, they had to stop when they could certainly read the word. The legibility distance was longer than recognizability one. Although these distances became longer according to letter size, there was no significant difference between 500 mm Japanese letters and 450 mm ones. The alphabetic words were easier to read than Japanese ones and alphanumeric ones. It was suggested that to get the same visibility the letter height of the alphabet was around 70 % of the Japanese letters. Some methodological issues in the experiment concerning design practices were also discussed.

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According to the latest report of HDR/UNDP, Sweden is ranked in the top as one of the gender-empowered countries. However, the reality of Swedish women in physics is still severe in terms of equal opportunities concerning education and academic career. Therefore, almost all of the universities in Sweden, which have physics faculties/departments, need to work on (or struggle for) equality between the sexes, regardless of section (e.g., department, faculty, whole university).

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