54 research outputs found
The Expression and Function of Fatty Acid Transport Protein-2 and -4 in the Murine Placenta
Background: The uptake and trans-placental trafficking of fatty acids from the maternal blood into the fetal circulation are essential for embryonic development, and involve several families of proteins. Fatty acid transport proteins (FATPs) uniquely transport fatty acids into cells. We surmised that placental FATPs are germane for fetal growth, and are regulated during hypoxic stress, which is associated with reduced fat supply to the fetus. Methodology/Principal Findings: Using cultured primary term human trophoblasts we found that FATP2, FATP4 and FATP6 were highly expressed in trophoblasts. Hypoxia enhanced the expression of trophoblastic FATP2 and reduced the expression of FATP4, with no change in FATP6. We also found that Fatp2 and Fatp4 are expressed in the mouse amnion and placenta, respectively. Mice deficient in Fatp2 or Fatp4 did not deviate from normal Mendelian distribution, with both embryos and placentas exhibiting normal weight and morphology, triglyceride content, and expression of genes related to fatty acid mobilization. Conclusions/Significance: We conclude that even though hypoxia regulates the expression of FATP2 and FATP4 in human trophoblasts, mouse Fatp2 and Fatp4 are not essential for intrauterine fetal growth. © 2011 Mishima et al
Building of minimum air temperature forecast system using the Internet -Design of the forecast website-
The purpose of this study is to build a forecast system for predicting at minimum air
temperature in the next morning from the meteorological data, such as air temperature,
humidity, and the amount of solar radiation, in a field in the evening on the previous day. The
meteorological data are sent to a relay server, and then, transferred to a PC in our laboratory
of Okayama University by executing the computer program to import the data which are used
to calculate the predicted values of minimum air temperature. The predicted minimum air
temperatures are released for the farmers on the website in the server of Okayama University.
The website is also created by our laboratory. As a result, the predicted minimum air
temperatures agreed with the measured ones
Characteristics and mechanism of low temperature dehydrochlorination of poly(vinyl chloride) in the presence of zinc(II) oxide
Characteristics of low temperature (473 K) dehydrochlorination of PVC powder in the presence of ZnO were studied in nitrogen flow and a reaction mechanism was proposed. It was revealed that a large portion of chlorine (ca. 70%) in PVC powder reacts with ZnO accompanying evolution of water and a slight amount of HCl (ca. 0.5%) without any organic gas. Analysis of the solid product by SEM, XRD and IR suggested that an apparent solid-solid reaction proceeds at 473 K via formation of a liquid phase which acts as reaction promoter and that the solid product is abundant in aliphatic (CH)(n) polymer. It was concluded that the first step of the dehydrochlorination is cross-linking C-C single bond formation in a polymer chain or among polymer chains followed by isomerization to polyene and aromatics.ArticlePOLYMER DEGRADATION AND STABILITY. 97(4):584-591 (2012)journal articl
Method for predicting minimum air temperature in the next morning using local meteorological observation data - Improvement on minimum air temperature forecasting system utilizing the Internet -
We have developed a minimum air temperature forecasting system using local meteorological
observation data in order to prevent or mitigate the frost damage. In this paper, the correlation between the meteorological factors and the decrease in air temperature during the night was shown. Then minimum air temperature was predicted by the multiple regression equation that uses air temperature and humidity at 18:00 as explanatory variables. As the result, the root mean square error (RMSE) was 2.8°C. When the difference of air temperature between 17:00 and 18:00 was used for the prediction instead of humidity, the RMSE was 3.5°C. Next, the prediction was carried out only in clear nights, then the equation that use air temperature and humidity at 18:00 showed that the RMSE was 1.3°C. Although the predictive accuracy of the equations for clear nights is low on cloudy or rainy nights, we can forecast safely on frosty nights by using those equations in combination with the equations for all nights
Concanavalin A-mediated T cell proliferation is regulated by herpes virus entry mediator costimulatory molecule
T cell activation is regulated by two distinct signals, signals one and two. Concanavalin A (ConA) is an antigen-independent mitogen and functions as signal one inducer, leading T cells to polyclonal proliferation. CD28 is known to be one of major costimulatory receptors and to provide signal two in the ConA-induced T cell proliferation. Here, we have studied the implication of other costimulatory pathways in the ConA-mediated T cell proliferation by using soluble recombinant proteins consisting of an extracellular domain of costimulatory receptors and Fc portion of human IgG. We found that T cell proliferation induced by ConA, but not PMA plus ionomycin or anti-CD3 mAb, is significantly inhibited by herpes virus entry mediator (HVEM)-Ig, even in the presence of CD28 signaling. Moreover, the high concentration of HVEM-Ig molecules almost completely suppressed ConA-mediated T cell proliferation. These results suggest that HVEM might play more important roles than CD28 in ConA-mediated T cell proliferation. © 2013 The Society for In Vitro Biology
Rapid proliferation of activated lymph node CD4+ T cells is achieved by greatly curtailing the duration of gap phases in cell cycle progression
Peripheral T cells are in G0 phase and do not proliferate. When they encounter an antigen, they enter the cell cycle and proliferate in order to initiate an active immune response. Here, we have determined the first two cell cycle times of a leading population of CD4+ T cells stimulated by PMA plus ionomycin in vitro. The first cell cycle began around 10 h after stimulation and took approximately 16 h. Surprisingly, the second cell cycle was extremely rapid and required only 6 h. T cells might have a unique regulatory mechanism to compensate for the shortage of the gap phases in cell cycle progression. This unique feature might be a basis for a quick immune response against pathogens, as it maximizes the rate of proliferation.In Pres
CYK4 relaxes the bias in the off-axis motion by MKLP1 kinesin-6
Centralspindlin, a complex of the MKLP1 kinesin-6 and CYK4 GAP subunits, plays key roles in metazoan cytokinesis. CYK4-binding to the long neck region of MKLP1 restricts the configuration of the two MKLP1 motor domains in the centralspindlin. However, it is unclear how the CYK4-binding modulates the interaction of MKLP1 with a microtubule. Here, we performed three-dimensional nanometry of a microbead coated with multiple MKLP1 molecules on a freely suspended microtubule. We found that beads driven by dimeric MKLP1 exhibited persistently left-handed helical trajectories around the microtubule axis, indicating torque generation. By contrast, centralspindlin, like monomeric MKLP1, showed similarly left-handed but less persistent helical movement with occasional rightward movements. Analysis of the fluctuating helical movement indicated that the MKLP1 stochastically makes off-axis motions biased towards the protofilament on the left. CYK4-binding to the neck domains in MKLP1 enables more flexible off-axis motion of centralspindlin, which would help to avoid obstacles along crowded spindle microtubules
Rapid G0/1 transition and cell cycle progression in CD8+ T cells compared to CD4+ T cells following in vitro stimulation
T-cell population consists of two major subsets, CD4+ T cells and CD8+ T cells, which can be distinguished by the expression of CD4 or CD8 molecules, respectively. Although they play quite different roles in the immune system, many of their basic cellular processes such as proliferation following stimulation are presumably common. In this study, we have carefully analyzed time–course of G0/1 transition as well as cell cycle progression in the two subsets of quiescent T-cell population following in vitro growth stimulation. We found that CD8+ T cells promote G0/1 transition more rapidly and drive their cell cycle progression faster compared to CD4+ T cells. In addition, expression of CD25 and effects of its blockade revealed that IL-2 is implicated in the rapid progression, but not the earlier G0/1 transition, of CD8+ T cells. © 2017 The Societies and John Wiley & Sons Australia, LtdEmbargo Period 12 month
- …