Activation of the mitogen-activated protein kinase pathway is involved in and sufficient for megakaryocytic differentiation of CMK cells

Activation of the mitogen-activated protein (MAP) kinase pathway has been associated with both cell proliferation and differentiation. Constitutively activated forms of Mek (MAP kinase/Erk kinase) and Erk (MAP kinase) have been previously shown capable of inducing differentiation or proliferation in nonhematopoietic cells. To specifically examine the role of Erk activation in megakaryocytic growth and development, we activated the MAP kinase pathway by the transfection of constitutively activated Mek or Erk cDNA into a human megakaryoblastic cell line, CMK, by electroporation. The CMK transfectant clones that expressed constitutively activated Mek or Erk showed morphologic changes of differentiation. Transfected cells also showed expression of mature megakaryocytic cell surface markers. The MAP kinase pathway was also activated by treatment of the hematopoietic cells with a cytokine that activates Erk. The treatment of CMK cells with stem cell factor (SCF ) caused MAP kinase activation and induced differentiation by the expression of mature megakaryocytic cell surface markers. The effects of the SCF treatment were inhibited by pretreatment with a specific inhibitor of the MAP kinase pathway, PD98059. In this report, we conclude that activation of the MAP kinase pathway was both necessary and sufficient to induce differentiation in this megakaryoblastic cell line.     

Fluoride exposure in cervids inhabiting areas adjacent to aluminum smelters in Norway. I. Residue levels

Mandibular fluorine concentrations were determined in 1,425 red deer (Cervus elaphus), 240 moose (Alces alces), and 424 roe deer (Capreolus capreolus) collected in Norway from 1990 to 1993 in seven municipalities in which aluminum smelters are located, in eight neighboring municipalities, and in eight reference areas representing background levels. Background fluorine concentration was significantly correlated with age in all three species. Roe deer had the highest mean background fluorine level in each age group, followed by red deer. Due to differences in fluoride exposure, large variations in bone fluorine residues were evident between locations. In Ardal, the district most severely exposed to fluoride contamination, nine of ten cervids had fluorine concentrations exceeding background levels. The proportions of red deer with fluorine residues exceeding background levels also were high in neighboring municipalities to Ardal. We propose that roe deer are a better biomonitor of local fluoride exposure than red deer and moose, due to their more sedentary behavior.     

Robust pose estimation and recognition using non-gaussian modeling of appearance subspaces

We present an original appearance model that generalizes the usual Gaussian visual subspace model to non-Gaussian and nonparametric distributions. It can be useful for the modeling and recognition of images under difficult conditions such as large occlusions and cluttered backgrounds. Inference under the model is efficiently solved using the mean shift algorithm     

Transport, chemical and electrochemical processes in a planar solid oxide fuel cell: Detailed three-dimensional modeling

A detailed numerical three-dimensional (3D) model for a planar solid oxide fuel cell (SOFC) is developed in this paper. The 3D model takes into account detailed processes including transport, chemical and electrochemical processes taking place in the cell. Moreover, effects of the composite electrodes are taken into account by considering an electrochemically active layer of finite thickness in each of the electrodes. The developed model is applied to a repeating unit of an anode-supported SOFC working under direct internal reforming conditions. Detailed results for chemical species, temperature, current density and electric potential distribution are presented and discussed. It was found that the temperature distribution across the cell is more uniform in the interconnects than in the inner part of the cell. However, only small differences in the electric potential between the electrode and the corresponding interconnect are found. The current density in the electrodes is found to be high near the electrolyte and low deep into the electrochemically active layer. The current density is also low under the ribs of the interconnects.     

Hypothesized simple factor structure for the Alcohol Expectancy Questionnaire: Confirmatory factor analysis.

This study proposed and tested a theoretical factor structure for the Alcohol Expectancy Questionnaire (AEQ; S. A. Brown, M. S. Goldman, A. Inn, & L. R. Anderson [see record 1981-01217-001]). Factors were hypothesized to (a) reflect either positive or negative reinforcement, and (b) target either personal feelings or social contexts, resulting in 4 hypothesized factors (Social Enhancement, Social Coping, Personal Enhancement, Personal Coping). Participants were 180 male and 226 female undergraduates who completed the AEQ and additional self-report measures. Confirmatory factor analysis revealed that the hypothesized model fit the data. Post hoc adjustments further improved the model. Finally, a higher order factor model fit the data best. Factors correlated in hypothesized ways with other measures: (a) Only Personal Coping expectancies correlated with negative affect; (b) self-efficacy to resist drinking for emotional relief correlated highest with Personal Coping; and (c) self-efficacy to resist social pressure to drink correlated highest with Social Enhancement. Correlations with B. C. Leigh and A. W. Stacy's (see record 1993-35856-001) Drinking Expectancy Questionnaire indicated congruent and divergent validity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Severity of psychosocial stress and outcome of alcoholism treatment.

Examined the relation between stressful life events and drinking outcome among 129 male alcoholics (aged 22–70 yrs) who had completed an alcohol treatment program. Life events were assessed for the year prior to treatment and for the 3 mo after treatment and were rated on a modified version of the Psychiatric Epidemiology Research Interview and the Contextual Rating System (G. W. Brown and T. O. Harris, 1982). Approximately 40% of the pretreatment stressors were found to be directly or indirectly related to alcohol use. When stressors related to drinking were excluded from consideration, men who returned to drinking after treatment were found to experience more severe or highly threatening stress before their relapse than men who remained abstinent during the follow-up period. These data suggest that although less severe stress may not increase risk for relapse, acute severe stressors and highly threatening chronic difficulties may be associated with elevated relapse risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Growth factor stimulation of hematopoietic cells leads to membrane translocation of AKT1 protein kinase

AKT1 is the human homolog of the v-akt oncogene. AKT1 has two distinct protein domains, one serine/threonine kinase domain and one pleckstrin homology (PH) domain. We studied the expression and activity of AKT1 in hematopoietic cell lines. The expression of AKT1 was constitutive in hematopoietic cells of various stages of development. In the growth factor dependent MO7e cells, serum and growth factor starvation resulted in an early 50% fall in activity which was maintained over 24 h. Treatment of cells which growth factors or agents which induce differentiation activated AKT1. The subcellular localization of AKT1 in MO7e cells was altered as it was activated. High AKT1 kinase activity was associated with membrane fractions in stimulated cells, in contrast to the much lower AKT1 activity in membranes of cells starved of serum and growth factor for 1 h. These results demonstrate AKT1 kinase activity and its regulation by extracellular signaling factors in vivo in hematopoietic cells, and suggest that the activation of AKT1 involves intracellular translocation of the kinase from cytosol to membrane.     

Theoretical and experimental evidence of different wettability classes

In this paper we analyze data from thirteen North Sea sandstone reservoirs that fall into the large group of intermediate wettability. By dividing this group into three sub-classes, fractionally-wet (FW), mixed-wet large (MWL) and mixed-wet small (MWS), we find an improved understanding of the intermediate-wet state. In the fractionally-wet state oil- and water-wet sites are random with respect to size, while in the mixed-wet state water- and oil-wet pores are sorted by size. We assume two classes of mixed wettability; MWL where the large pores are oil-wet and MWS where the small pores are oil-wet. The paper includes both theoretical considerations, pore–scale observations by ESEM, SEM and thin sections, as well as core scale wettability indices that indicate that these wettability states may exist in reservoirs.     

Calcitonin and bipolar disorder: a hypothesis revisited

Many of the great discoveries and developments in the sciences and the arts were made by people who were 'mentally different'. Some such pioneers or innovators had experiences that were indistinguishable from the phenomena defined as mental illness (or madness). It has been argued that such experiences are a necessary constituent of the creative process, and that this may apply to the sciences as much as to the arts. Increasingly, scientists propose a means by which it may be possible to identify (and eliminate) the factors that influence the altered states associated with mental illness. This may be an appropriate time to review the cultural and social significance of all forms of 'madness', especially in the light of emerging models of psychiatric nursing practice.