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Sophisticated functions of biological tissues are supported by small biological units of cells that are localized within a region of 100 μm scale. The cells in these units secrete molecules to form their microenvironment to play a vital role in biological functions. Various microfluidic devices have been developed to analyze the microenvironment but were not designed for cells in a culture dish in a confluent condition, a typical setup for cell and tissue cultivation. This study presents a novel glass capillary-based microfluidic device for studying confluent cells in a culture dish. The multiple capillaries allow the device to confine the local flow in 100 μm or smaller scale to form two adjacent regions with different chemical properties; it can simultaneously perform local cell stimulation and collect secreted molecules from the stimulated cells. Cell removal was achieved upon trypsin stimulation from a limited area (3.8 × 10

We characterize here the airborne lipids (β/ω-hydroxy fatty acids: FAs) specific to soil microbes and plant waxes over suburban Tokyo in simultaneously collected aerosols and rainwater from spring ...

Thermoresponsive poly(N-isopropylacrylamide) (PIPAAm)-immobilized surfaces for controlling cell adhesion and detachment were fabricated by the Langmuir-Schaefer method. Block copolymers composed of polystyrene and PIPAAm (St-IPAAms) having various chain lengths and compositions were synthesized by reversible addition-fragmentation chain transfer radical polymerization. The St-IPAAm Langmuir film at an air-water interface was horizontally transferred onto a hydrophobically modified glass substrate while regulating its density. Atomic force microscopy images clearly visualized nanoscaled sea-island structures on the surface. By adjusting both the composition of St-IPAAms and the density of immobilized PIPAAms, a series of thermoresponsive surfaces was prepared to control the strength, rate, and quality of cell adhesion and detachment through changes in temperature across the lower critical solution temperature range of PIPAAm molecules. In addition, a two-dimensional cell structure (cell sheet) was more rapidly recovered on the optimized surfaces than on conventional PIPAAm surfaces. These unique PIPAAm surfaces are suggested to be useful for controlling the strength of cell adhesion and detachment.

Reactions of Pd(PPh3)4 with P(═E)(NiPr2)(naph) (6, E = S; 7, E = O) (naph = 1,8-naphthylene) having a strained four-membered P(V)-phosphacycle gave dimeric complexes [Pd{κ2P,C-μ2-PE- P(═E)(NiPr2)(naph)}(PPh3)]2 (9, E = S; 10, E = O), in which a Pd metal has been inserted into a P−C bond of the phosphacycle to form a phosphapalladacycle having a P(V) donor, and the two phosphapalladacycle units have been mutually bridged with E═P groups, as confirmed by X-ray structure analysis for thermodynamically more stable racemic isomers 9a and 10a. The meso-to-racemic isomerization observed for the simultaneously formed meso isomer 9b, and probably also for the corresponding meso isomer 10b, indicated partial dissociation of 9 and 10 taking place to their monomer units in solution, which were actually trapped as [Pd{κ2P,C-P(═E)(NiPr2)(naph)}(dppe)] by treatment with bidentate dppe (dppe = 1,2-bis(diphenylphosphino)ethane). On the other hand, a similar treatment of 9a with monodentate PMe3 and PEt2Ph resulted in a tr...

With a novel assay using isolated ferret detrusor to estimate beta(3)-adrenoceptor agonistic activity, we found that a series of glycine derivatives of ritodrine, a beta(2)-adrenoceptor agonist, are potent beta(3)-adrenoceptor agonists, with excellent selectivity versus beta(1) and beta(2) subtypes. Substitution of halogens in the phenyl ring increased potency and selectivity for the beta(3)-adrenoceptor, and this was dependent upon the position of the halogens. The chlorine-substituted derivatives 3f-i exhibited potent beta(3)-adrenoceptor-mediated relaxation of ferret detrusor (EC(50) = 0.93, 11, 14, and 160 nM) and higher potency at beta(3)-adrenoceptors than at beta(1) or beta(2). The intravenous administration of 3h significantly reduced the urinary bladder pressure in anesthetized male rats (ED(50) = 48 microg/kg) without cardiovascular side effects. This article is the first report of structure-activity relationships (SAR) concerning beta(3)-adrenoceptor agonists as agents for the treatment of urinary frequency and incontinence.

On utilise un melange 0,04 m Na 2 CO 3 et 0,16 M NaHCO 3 comme electrolyte. Enrichissement en chlorure, phosphate, nitrate et sulfate avant chromatographie ionique avec detection conductimetrique

We established a hybridoma clone that produced anti-bleomycin hydrolase antibody. The subclass of the monoclonal antibody was immunoglobulin M. The antibody significantly reacted with bleomycin hydrolase from rabbit tissues, mouse livers, sarcoma 180, and adenocarcinoma 755 but not significantly with that from MH 134 and Ehrlich carcinoma. The enzyme from L5178Y cells showed an intermediate reactivity. Bleomycin hydrolase was purified from rabbit liver by immunoaffinity with the monoclonal antibody and DEAE gel chromatography. Approximately 1300-fold-purified bleomycin hydrolase was obtained. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and isoelectric focusing on a polyacrylamide slab gel of purified bleomycin hydrolase showed a single band with an apparent Mr of 48K and an isoelectric pH of 5.2. The molecular weight of bleomycin hydrolase determined on gel filtration high-performance liquid chromatography was ca. 300K, suggesting a hexameric enzyme. The enzyme showed an optimum pH of 6.8-7.8 and gave a Vmax value of 6.72 mg min-1 mg-1 for peplomycin and 9.24 mg min-1 mg-1 for bleomycin B2 and a Km value of 0.79 mM for both substrates. The enzyme was inhibited by E-64, leupeptin, p-tosyl-L-lysine chloromethyl ketone, N-ethylmaleimide, Fe2+, Cu2+, and Zn2+ but was enhanced by dithiothreitol. The results suggest that bleomycin hydrolase is a thiol enzyme.

La combinaison d'une modification de matrice pour echange d'ions double avec la chromatographie ionique permet la determination d'impuretes anioniques (par exemple SO 4 2− ) dans des solutions concentrees et d'electrolytes (par exemple NaHCO 3 0,1 a 0,5 M)

Resultats de l'etude par voltammetrie cyclique, en presence d'une electrode de carbone vitreux, dans des solutions aqueuses de dioxanne. Mise en evidence de l'influence de l'atome central sur les reactions d'electrode