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Mitogen-activated protein (MAP) kinase kinase (MAPKK) is a recently characterized activator of MAP kinase (MAPK), and is considered to be regulated by a protooncogene product c-Raf-1. It is, however, unclear whether the signals originating from c-Raf-1 utilize this phosphorylation cascade to lead to oncogenesis. To clarify this point, we isolated rat MAPKK cDNAs, and identified two distinct cDNAs encoding MAPKK and a highly related kinase, both with molecular weights of approximately 45 kDa (MEK1 and MEK2). Genomic Southern blot analyses suggested that MAPKK may form a large gene family.

Human lysozyme is a monomeric secretory protein composed of 130 amino acid residues, with four intramolecular disulfide bonds and no oligosaccharides. In this study, a mutant protein, [Ala128] lysozyme, which cannot fold because it lacks a disulfide bond, Cys6-Cys128, was expressed in mouse fibroblasts and was found to be mostly degraded in the cells, whereas the control wild-type lysozyme was quantitatively secreted into the media. The degradation of [Ala128]lysozyme was independent of the transport from the endoplasmic reticulum to the Golgi apparatus. The degradation was greatly inhibited by incubation of cells at 15 degrees C, but was minimally affected by treatment of cells with the lysosomotropic agent, chloroquine, implying a non-lysosomal process. Additional mutations (Gly48-->Ser or Met29-->Thr) were created to make asparagine-linked (N-linked) glycosylation site in the [Ala128]lysozyme, and the resultant double mutants, [Ser48, Ala128]lysozyme and [Thr29, Ala128]lysozyme, were analyzed with respect to their intracellular degradation. These mutant proteins were susceptible to N-linked glycosylation, and were degraded in a similar manner to that of [Ala128] lysozyme, except that the onset of degradation of [Ser48, Ala128]lysozyme and [Thr29, Ala128] lysozyme, but not of [Ala128]lysozyme, was preceded by a lag period of up to 60 min. Furthermore, the degradative double mutants, [Ser48, Ala128]lysozyme and [Thr29, Ala128]lysozyme, were glycosylated post-translationally as well as co-translationally. These observations suggest that there is some interaction between the mechanisms of glycosylation and degradation.

PtdIns 3-kinase associates with certain activated protein-tyrosine kinase receptors and with the pp60c-src/polyoma middle-T complex, suggesting that the enzyme is involved in growth regulation. The purified PtdIns 3-kinase appears to have two subunits, of 85 kDa and 110 kDa. Structural analysis at protein and cDNA levels revealed two forms of the 85 kDa subunit, one which associates with PtdIns 3-kinase activity termed p85 alpha, and a protein of unknown function, p85 beta. Both 85 kDa proteins contain src-homology regions 2 and 3 (SH2 and SH3), but lack enzymic activity, suggesting that they may be regulatory subunits of PtdIns 3-kinase. To probe their structure and function further, p85 alpha and p85 beta have been expressed and purified in large amounts from insect cells by using baculovirus vectors. Specific antisera detect p85 alpha, but not p85 beta, associated with PtdIns 3-kinase activity in various cell types. Co-expression studies in insect cells have shown that p85 alpha and p85 beta are substrates for the protein-tyrosine kinases of epidermal growth factor, colony-stimulating factor 1 and c-erbB2 receptors and the src family kinase p59c-fyn. Both p85 alpha and p85 beta form tight complexes with these protein-tyrosine kinases as measured by immunoprecipitation and kinase assays in vitro. The specificity of binding of free p85 is less restricted than that of p85 in the active PtdIns 3-kinase complex with the 110 kDa protein. The relevance of these results to growth-factor-induced PtdIns 3-kinase activation is discussed.

Purified bovine brain phosphatidylinositol 3-kinase (Pl3-kinase) is composed of 85 kd and 110 kd subunits. The 85 kd subunit (p85 alpha) lacks Pl3-kinase activity and acts as an adaptor, coupling the 110 kd subunit (p110) to activated protein tyrosine kinases. Here the characterization of the p110 subunit is presented. cDNA cloning reveals p110 to be a 1068 aa protein related to Vps34p, a S. cerevisiae protein involved in the sorting of proteins to the vacuole. p110 expressed in insect cells possesses Pl3-kinase activity and associates with p85 alpha into an active p85 alpha-p110 complex that binds the activated colony-stimulating factor 1 receptor. p110 expressed in COS-1 cells is catalytically active only when complexed with p85 alpha.

The mutant human lysozyme, [Ala77, Ala95]lysozyme, in which the disulfide bond Cys77-Cys95 is eliminated, is known to exhibit increased secretion in yeast, compared to wild-type human lysozyme [Taniyama, Y., Yamamoto, Y., Nakao, M., Kikuchi, M. & Ikehara, M. (1988) Biochem. Biophys. Res. Commun. 152, 962-967]. To investigate this phenomenon, mammalian cells were used to analyze the secretion kinetics of [Ala77, Ala95]lysozyme and wild-type human lysozyme. The secretion rate of [Ala77, Ala95]lysozyme during the 150-min chase period was significantly accelerated [half-life (t1/2) = 29 min] compared to that of wild-type human lysozyme (t1/2 = 83 min), when expressed at the same levels within the cells. In contrast, after the 150-min chase, the rates of disappearance of both wild-type and mutant human lysozymes within the cells were similar, and considerably slower (t1/2 = 220 min), respectively. The remaining intracellular wild-type human lysozyme was localized mainly in the endoplasmic reticulum, whereas accelerated transport of the [Ala77, Ala95]lysozyme mutant protein from the endoplasmic reticulum to the Golgi apparatus was observed. Also in yeast cells, similar secretion kinetics and the differences in t1/2 for wild-type and mutant human lysozymes during the early chase period were observed. The two-phase kinetics of disappearance of intracellular human lysozymes suggest that only a proportion of the proteins becomes secretion competent soon after synthesis and is completely secreted during the early chase period, whereas others enter the distinct, slow pathways of intracellular transport and/or degradation. Increased secretion of [Ala77, Ala95]lysozyme is possibly due to enhanced competence for secretion acquired in the endoplasmic reticulum at the early stage of transport events, which is closely connected with the removal of a disulfide bond.

The human phosphatidylinositol (PI) 3-kinase p85 alpha subunit gene and its homologue p85 beta were assigned to human chromosomes by analysis of their segregation in a panel of somatic cell hybrids using human-specific polymerase chain reaction primers. The p85 alpha locus was only present in hybrids retaining the human chromosome 5q. The presence of the p85 beta locus coincided with the presence of chromosome 19. The precise chromosomal sublocalization of these two genes was then determined by in situ hybridization. We confirmed the localization of the p85 alpha gene at 5q12-q13, as recently described (Cannizzaro, L.A., Skolnik, E.Y., Margolis, B., Croce, C.M., Schlesinger, J. & Huebner, K. (1991). Cancer Res., 51, 3818-3820) and positioned the p85 beta locus at 19q13.2-q13.4.

The very early stages of the human B-cell differentiation pathway are poorly understood, primarily because of the lack of appropriate permanent cell lines. Epstein-Barr virus (EBV) is a putative human oncogenic virus which transforms human B cells in vitro into continuously proliferating cells. It has been believed that EBV transforms mature B cells, but recently, transformation of immature pre-B-cell lines has been reported, suggesting that EBV might also transform cells much earlier in the B-cell lineage. We report here the establishment of cell lines transformed by EBV at various stages of the B-cell differentiation pathway. Interestingly, two lines showed the complete absence of immunoglobulin synthesis and the lack of immunoglobulin gene rearrangement despite containing EBV genome and surface markers of B cells. Our results indicate that EBV can infect and transform cells of the B lymphocyte lineage even before immunoglobulin gene rearrangement.

Nurses who had learned the Nightingale's nursing method in the middle of the Meiji Era systematized nursing in Japan. In 1884, modern nursing began in Tokyo. In Kyushu, nursing education started in Fukuoka Hospital ten years later. At that time, the teaching of nurses was done by individual doctors who taught them all the necessary subjects. This study identifies the ethical criteria which the educators of that time had as the goal of nursing education.

In order to estimate the direct effect of the physical vibration on the peripheral blood flow rate, we measured the water flow rate in a silicon capillary tube whose end was vibrated. Three types of vibration were added to the tube and the frequency of the vibration covered 1-2000 Hz. It is shown that the water flow rate reduces under the vibration and this reduction strongly depends on the frequency and the type of the vibration. The main reason for this dependence is shown to be as follows. The vibration stretches the tube and the average length of the tube is longer under the vibration than when under no vibration, and the average tube radius is smaller under the vibration. This causes the reduction of the flow rate under vibration. Because the stretch of the tube strongly depends on the frequency and the type of the vibration, the above dependence of the water flow rate finally appears.

The purpose of this study is to analyse the cause of itching and explore the relationships between pruritus senilis and various stimuli. Sample of 132 men and 238 women with ages ranging from 60 to 96 years were used in our study. Pruritus senilis is not significantly related to cosmetics and soap. Nevertheless, statistically significant correlations were found between pruritus senilis and physical stimuli (e. g., warmth, coldness, dryness). These observations could suggest that pruritus senilis is caused by changes of temperature.

In nursing, if we know an elderly person's mental condition, and that which does not make him/her too tired, this method can be very useful. Using this method we predicted the MAS score from scores of Y-G scales. We obtained the MAS score results by the following formula: MAS score not equal to 0.31 X Lack of objectivity +0.41 X Inferiority feelings -0.15 X Ascendance +0.34 X Y-G Nervousness +0.30 X Y-G Depression +9.54.

A41 304 at 400 mug/kg produced depression of body weight gains in the rat dams but did not increase the number of the fetuses with gross malformations. At 400 mug/kg of dexamethasone, body weight gains of the rat dams were markedly depressed and fetuses presented cleft palate and depression of the placental weight, body weight and crown-rump length. As for the influence of both drugs upon the fetal skeleton, ossification of the odontoid process and metatarsus was delayed and lumbar ribs increased. Dexamethasone at 400 mug/kg, in addition to these findings, caused prominently delayed ossification to the caudal vertebrae. When A41 304 at 1600 mug/kg and dexamethasone at 400 mug/kg were given to pregnant mice, cleft palate occurred with high incidences, but neither visceral abnormalities nor skeletal malformations attributable to the drug administration were observed. The critical period of cleft palate which was noted in the mice given A41 304 was day 11 through day 15 of pregnancy, mainly 11 approximately 13 of pregnancy. Cleft palate was seen in a dose-related manner in either A41 304-treated groups or dexamethasone-treated groups, but the incidence at the same dosage level was higher in dexamethasome-treated groups than in A41 304-treated groups.

The vibration hazards in peripheral blood vessels as an occupational origin is caused by using pneumatic vibrating tools. In order to know that the major part of causes is whether due to the direct effects of the physical vibration or due to the effects depended on the excitations of peripheral nervous system, an model experiment was employed to estimate the direct effect of the physical vibration. In our experiments, water as fluid was used instead of blood. The silicon capillary tube as same the physical qualities and conditions as blood vessels was vibrated by oscillator. The silicon capillary tube was exposed by following three type of vibration mode to flow axis; i) sine wave of transverse vibration, ii) rectangular wave of transverse vibration, and iii) sine wave of longitudinal vibration. The range of vibration frequency covered 1-2000 Hz. The averaged acceleration by oscillating vibration and the vibration strength level were estimated about 1-200 G and 150 dB, respectively. The observed decreases of water flow rate due to vibration extremely depend on frequency. The decrease ratio of water flow rate by vibration was at maximum 12% down compare with the cases of non vibration. In these observed results by this model experiment, it should be concluded that the direct effect of the physical vibration to the blood flow was not too strong to cause the actual vibration hazards.

Kitakyushu city is characterized by the following aspects, that is a large amount of alcohol consumption relative to other cities high death rate of liver cirrhosis and chronic liver diseases many recipients of the Daily Life Security a large population of aged people. This study was carried out to investigate the interrelation of industrial structure and drinking status of people living under these situations in Kitakyushu. The close association between drinking and liver diseases was found. Furthermore, a large proportion of drinkers were recipients of the Daily Life Security and this is one of the problems to be resolved. It also became clear that it is not easy to stop drinking for habitual drinkers in spite of the presence of liver diseases and the loss of feeling of satisfaction with life which may be triggered by retirement from job possibly hampers them from problem drinking. With an increase of a population of aged, an increase of alcoholism among them may cause serious, local but social problems. These problems may not be resolved only by the effort of clinical medicine, also macroscopical point of views through social structure, industrial structure, a policy of welfare, public health services etc. are required. A part of the study was presented at the 17th, 18th and 19th Conference of Japanese Medical Society of Alcohol Studies.