147 research outputs found
State of Efflux of Scavenging Air through the Scavenging Ports
In order to make clear how the efflux angle changes in a small crankcase scavenged engine cylinder and in a large loop scavenged engine cylinder, the inlet flow pattern in the single cycle model cylinder has been observed by a high speed motion camera. In general, the scavenging air stream is not effluent in the designed direction of the scavenging port at comparatively slight opening, and the efflux angle changes in proportion to port opening advance. In a small crankcase scavenged engine cylinder, to keep the scavenging air stream in the direction of the scavenging port it is effective to incline the scavenging air passage between the crankcase and the cylinder, and to make thicker the cylinder wall where located scavenging port. In a large loop scavenged engine cylinder to coincide the scavenging air stream with the direction of the scavenging port in the early stage of the scavenging, it has an effect to set the guide plate the position of 1/2 at port height
Recombinant human interleukin 6 (B-cell stimulatory factor 2) is a potent inducer of differentiation of mouse myeloid leukemia cells (M1)
AbstractRecombinant human interleukin 6 (IL-6), a lymphokine involved in the final differentiation of activated B-cells into antibody-forming cells, greatly suppressed proliferation and induced differentiation of murine myeloid leukemia cells (M1) into mature macrophage-like cells. When M1 cells were treated with IL-6, their growth was completely arrested as early as on day 2, and they were induced to differentiate morphologically into macrophage-like cells. Differentiation-associated properties such as phagocytic activity, adherence to the dish surface, Fc and C3 receptors, were also induced within 24 h by IL-6, and they reached their respective maximal levels on day 2 or 3. The potency of IL-6 in suppressing proliferation and inducing differentiation was much greater than that of 1α,25-dihydroxyvitamin D3 one of the most potent inducers of M1 cells. The present report indicates that IL-6 is involved in the differentiation of not only B-cells but also myeloid leukemia cells
Production of Interleukin 2 in Human Peripheral Blood Lymphocytes: Optimal Condition for its Culture
For the assay of the production of Interleukin 2 (IL-2) in human peripheral blood lymphocytes (human PBL), a study was made on the optimal condition for its culture.
1) The optimal condition for the production of IL-2 was considered to be incubation time of 24 hr, number of PBL of 1 x 106 cells/ml, and phytohemagglutinin-M (PHA-M) concentration of 1 — 5%
2) By one way mixed lymphocyte reaction (one way MLR), IL-2 activity similar in level to that by PHA-M stimulation could also be obtained. It was maximal at the 4th day of culture.
3) By PHA-P (0.06%) stimulation, IL-2 could also be produced similar to that by PHAM stimulation but it decreased in the order of Con A, PWM and PPD and hardly any production of IL-2 could be observed by LPS
Detection of Lymphocyte Subsets by Monoclonal Antibodies in Aged and Young Humans
With the use of Leu-series monoclonal antibodies, peripheral blood lymphocyte subsets in aged and young humans were determined.
1) In comparison with young individuals, Leu-1+ cells and Leu-2a+ cells were decreased, whereas Leu-7+ cells and Leu-3a/Leu-2a were increased in aged individuals.
2) No sex difference could be observed in lymphocyte subsets.
3) PHA response of lymphocytes showed a negative correlation with Leu-2a+ cells and a positive correlation with Leu-3a/Leu-2a in aged individuals
Interleukin-2 Production and Lymphocyte Proliferation in Aged and Young Humans
A study was made on the effect of aging on the production of Interleukin-2 (IL-2) and lymphocyte proliferation of human peripheral blood lymphocytes.
1) In comparison with young individuals, IL-2 production tended to decrease in aged individuals, while lymphocyte proliferation showed a significant decrease.
2) A significant correlation was observed between IL-2 production and lymphocyte proliferation in both the aged and young human populations.
3) IL-2 production showed a negative correlation with Leu-2a positive rate and a positive correlation with Leu-3a/Leu-2a ratio in aged individuals
Immune Functions of Former Poison Gas Workers I. Mitogenic response of lymphocytes and serum factors
The relation of depressed immune function to carcinogenesis has been estimated in the living body. The authors have measured the immunological parameters in former poison gas workers, a group having a high risk of carcinogenesis, for comparison with age matched normal controls and the following results were obtained.
1) With regard to serum factors, no significant difference could be demonstrated between normal controls and poison gas workers in such immunoglobulins as IgG, IgA, and IgM, in acute phase reactants such as α1-AT, α1-AG, α2-HS and C3 and in such tumor markers as CEA, ferritin, and β2-microglobulin. Furthermore, no difference could be observed in the positive rate of immune complex and in complement activity.
2) No difference could be observed between the two groups with regard to tuberculin skin reaction and number of lymphocytes, but the longer the duration of work at the poison gas factory, the more significant was the increase in those who showed negative tuberculin skin reaction.
3) In comparison with normal controls, mitogenic response to PHA showed a significant decrease in poison gas workers, but no significant difference could be seen in mitogenic response to Con A and PPD and in mixed lymphocyte reaction.
4) No significant difference could be demonstrated between the two groups in the inhibitory effects of serum on mitogenic response to PHA and Con A and on mixed lymphocyte reaction
Digital quantitative analysis of mast cell infiltration in interstitial cystitis
AimsTo evaluate the significance of mast cell infiltration in interstitial cystitis (IC) by comparison with equally inflamed controls using a digital quantification technique. MethodsBladder biopsy specimens from 31 patients with Hunner type IC and 38 patients with non-Hunner type IC were analyzed. Bladder biopsy specimens from 37 patients without IC, including 19 non-specific chronic cystitis (non-IC cystitis) specimens and 18 non-inflamed bladder (normal bladder) specimens, were used as controls. Mast cell tryptase-, CD3-, CD20-, and CD138-immunoreactive cells were quantified using digital image analysis software to evaluate both mast cell and lymphoplasmacytic cell densities. Mast cell and lymphoplasmacytic cell densities were counted independently in the entire lamina propria and detrusor areas and compared among the four groups. ResultsIn the lamina propria, there were no significant differences in mast cell and lymphoplasmacytic cell densities between Hunner type IC and non-IC cystitis or between non-Hunner type IC and normal bladder specimens. In the detrusor, the mast cell densities were not significantly different among the four groups. Mast cell density was correlated with lymphoplasmacytic cell density, but not with clinical parameters. ConclusionsMast cell density is not significantly different between IC specimens and non-IC control specimens with a similar degree of background inflammation. The intensity of mast cell infiltration generally correlated with that of lymphoplasmacytic cells. We conclude that mast cell count is of no value in the differential diagnosis between IC and other etiologies
A Dipeptidyl Peptidase-4 Inhibitor, Des-Fluoro-Sitagliptin, Improves Endothelial Function and Reduces Atherosclerotic Lesion Formation in Apolipoprotein E–Deficient Mice
ObjectivesThe aim of this study was to investigate the antiatherogenic effects of the dipeptidyl peptidase-4 inhibitor, des-fluoro-sitagliptin (DFS).BackgroundThe new class of anti–type 2 diabetes drugs, dipeptidyl peptidase-4 inhibitors, improves glucose metabolism by increasing levels of active glucagon-like peptide (GLP)-1.MethodsEndothelial function was examined by acetylcholine-induced endothelium-dependent vasorelaxation using aortic rings and atherosclerotic lesion development in the entire aorta in apolipoprotein E–deficient mice fed a high-fat diet with or without DFS, and the antiatherogenic effects of DFS were investigated in cultured human macrophages and endothelial cells. Plasma levels of active GLP-1 were measured in patients with or without coronary artery disease.ResultsDFS significantly improved endothelial dysfunction (89.9 ± 3.9% vs. 79.2 ± 4.3% relaxation at 10−4 mol/l acetylcholine, p < 0.05) associated with increased endothelial nitric oxide synthase phosphorylation and reduced atherosclerotic lesion area (17.7% [15.6% to 25.8%] vs. 24.6% [19.3% to 34.6%], p < 0.01) compared with vehicle treatment. In cultured human macrophages, DFS significantly increased GLP-1-induced cytosolic levels of cyclic adenosine monophosphate compared with GLP-1 alone, resulted in inhibiting phosphorylation of c-jun N-terminal kinase and extracellular signal-regulated kinase 1/2 and nuclear factor-kappa B p65 nuclear translocation through the cyclic adenosine monophosphate/protein kinase A pathway, and suppressed proinflammatory cytokines (i.e., interleukin-1-beta, interleukin-6, and tumor necrosis factor-alpha) and monocyte chemoattractant protein-1 production in response to lipopolysaccharide. DFS-enhanced GLP-1 activity sustained endothelial nitric oxide synthase phosphorylation and decreased endothelial senescence and apoptosis compared with GLP-1 alone. In the human study, fasting levels of active GLP-1 were significantly lower in patients with coronary artery disease than those without (3.10 pmol/l [2.40 to 3.62 pmol/l] vs. 4.00 pmol/l [3.10 to 5.90 pmol/l], p < 0.001).ConclusionsA DPP-4 inhibitor, DFS, exhibited antiatherogenic effects through augmenting GLP-1 activity in macrophages and endothelium
Revealing the Hidden Spin-Polarized Bands in a Superconducting Tl Bilayer Crystal
The interplay of spin-orbit coupling and crystal symmetry can generate spin-polarized bands in materials only a few atomic layers thick, potentially leading to unprecedented physical properties. In the case of bilayer materials with global inversion symmetry, locally broken inversion symmetry can generate degenerate spin-polarized bands, in which the spins in each layer are oppositely polarized. Here, we demonstrate that the hidden spins in a Tl bilayer crystal are revealed by growing it on Ag(111) of sizable lattice mismatch, together with the appearance of a remarkable phenomenon unique to centrosymmetric hidden-spin bilayer crystals: a novel band splitting in both spin and space. The key to success in observing this novel splitting is that the interaction at the interface has just the right strength: it does not destroy the original wave functions of the Tl bilayer but is strong enough to induce an energy separation
Ultraflexible Wireless Imager Integrated with Organic Circuits for Broadband Infrared Thermal Analysis
Kawabata R., Li K., Araki T., et al. Ultraflexible Wireless Imager Integrated with Organic Circuits for Broadband Infrared Thermal Analysis. Advanced Materials 36, 2309864 (2024); https://doi.org/10.1002/adma.202309864.Flexible imagers are currently under intensive development as versatile optical sensor arrays, designed to capture images of surfaces and internals, irrespective of their shape. A significant challenge in developing flexible imagers is extending their detection capabilities to encompass a broad spectrum of infrared light, particularly terahertz (THz) light at room temperature. This advancement is crucial for thermal and biochemical applications. In this study, a flexible infrared imager is designed using uncooled carbon nanotube (CNT) sensors and organic circuits. The CNT sensors, fabricated on ultrathin 2.4 µm substrates, demonstrate enhanced sensitivity across a wide infrared range, spanning from near-infrared to THz wavelengths. Moreover, they retain their characteristics under bending and crumpling. The design incorporates light-shielded organic transistors and circuits, functioning reliably under light irradiation, and amplifies THz detection signals by a factor of 10. The integration of both CNT sensors and shielded organic transistors into an 8 × 8 active-sensor matrix within the imager enables sequential infrared imaging and nondestructive assessment for heat sources and in-liquid chemicals through wireless communication systems. The proposed imager, offering unique functionality, shows promise for applications in biochemical analysis and soft robotics
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