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In this study, we conducted a collaborative study on the classification between silicone oil droplets and protein particles detected using the flow imaging (FI) method toward proposing a standardized classifier/model. We compared four approaches, including a classification filter composed of particle characteristic parameters, principal component analysis, decision tree, and convolutional neural network in the performance of the developed classifier/model. Finally, the points to be considered were summarized for measurement using the FI method, and for establishing the classifier/model using machine learning to differentiate silicone oil droplets and protein particles.

Two tiny hairpin DNAs, CORE (dAGGCTTCGGCCT) and AP2 (dAGGCTXCGGCCT; X: abasic nucleotide), fold into almost the same tetraloop hairpin structure with one exception, that is, the sixth thymine (T6) of CORE is exposed to the solvent water (Kawakami, J. et al., Chem. Lett. 2001, 258-259). In the present study, we selected small peptides that bind to CORE or AP2 from a combinatorial pentapeptide library with 2.5 x 10(6) variants. On the basis of the structural information, the selected peptide sequences should indicate the essential qualifications for recognition of the hairpin loop DNA with and without a flipped base. In the selected DNA binding peptides, aromatic amino acids such as histidine for CORE and glutamine/aspartic acid for AP2 were found to be abundant amino acids. This amino acid preference suggests that CORE-binding peptides use pi-pi stacking to recognize the target while hydrogen bonding is dominant for AP2-binding peptides. To investigate the binding properties of the selected peptide to the target, surface plasmon resonance was used. The binding constant of the interaction between CORE and a CORE-binding peptide (HWHHE) was about 1.1 x 10(6) M(-1) at 25 degrees C and the resulting binding free energy change at 25 degrees C (DeltaG degrees (25)) was -8.2 kcal mol(-1). The binding of the peptide to AP2 was also analyzed and the resulting binding constant and DeltaG degrees (25) were about 4.2 x 10(4) M(-1) and -6.3 kcal mol(-1), respectively. The difference in the binding free energy changes (DeltaDeltaG degrees (25)) of 1.9 kcal mol(-1) was comparable to the values reported in other systems and was considered a consequence of the loss of pi-pi stacking. Moreover, the stabilization effect by stacking affected the dissociation step as well as the association step. Our results suggest that the existence of an aromatic ring (T6 base) produces new dominant interactions between peptides and nucleic acids, although hydrogen bonding is the preferable mode of interaction in the absence of the flipping base. These findings regarding CORE and AP2 recognition are expected to give useful information in the design of novel artificial DNA binding peptides.

Background: Mirtazapine, a noradrenergic and specific serotonergic antidepressant (NaSSA), shows multiple pharmacological actions such as inhibiting presynaptic α2 noradrenaline receptor (NAR) and selectively activating 5-hydroxytriptamine (5-HT) 1A receptor (5-HT1AR). Mirtazapine was also reported to increase dopamine release in the cortical neurons with 5-HT dependent manner. To examine whether mirtazapine has a therapeutic potency in Parkinson’s disease (PD), we examined this compound in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice model of PD. Results: Male C57BL/6 mice were subjected to MPTP treatment to establish a PD model. Mirtazapine was administered once a day for 3 days after MPTP treatment. MPTP-induced motor dysfunction, assessed by beam-walking and rota-rod tests, was significantly improved by administration of mirtazapine. Biochemical examinations by high performance liquid chromatography and western blot analysis suggested mirtazapine facilitated utilization of dopamine by increasing turnover and protein expression of transporters, without affecting on neurodegenerative process by MPTP. These therapeutic effects of mirtazapine were reduced by administration of WAY100635, an inhibitor for 5HT1AR, or of clonidine, a selective agonist for α2-NAR, or of prazosin, an inhibitor for α1-NAR, respectively. Conclusion: Our results showed mirtazapine had a therapeutic potency against PD in a mouse model. Because PD patients sometimes show depression together, it will be a useful drug for a future PD treatment.

For handling of a micromachine element and / or its parts, use of a micromechanical system is suitable. Thus, a pantograph mechanism is made from a plastic resin and superelastic hinges simultaneously using a small injection molding machine. The shape memory alloy having an effect of superelasticity is used as superelastic hinges. Therefore it is possible for superelastic hinges to have large bending displacements. The input and output displacements of the pantograph mechanism with superelastic hinges are measured and their linear relationship is confirmed. Then a micromechanical system for microbonding by adhesives is constructed using piezoelectric actuators, the pantograph mechanism and a needle. We confirmed that the proposed mechanical system performs well for microbonding by adhesives.

To handle a micromachine element and/or its parts, a micromechanical system is suitable. Thus, a pantograph mechanism is made from a plastic resin and superelastic hinges simultaneously by using a small injection molding machine. Superelastic hinges made of shape memory alloy have an effect of super-elasticity. Therefore it is possible for superelatsic hinges to have great bending displacements. The input and output displacements of the pantograph mechanism with superelastic hinges are measured and their linear relationship is confirmed. Then a micromechanical system for microbonding by adhesives is made from piezoelectric actuators, the pantograph mechanism and a needle. We confirmed that the proposed mechanical system performs well for microbonding by adhesives.

This paper proposes a method of application of micro amounts of adhesive resin by using a needle. The process of micro-application of the resin is experimentally investigated. The amount of adhesive resin on the needle is influenced by the shape and size of the needle. The micro-application of adhesive resin is dependent on the handling process of the needle to transfer adhesive resin on the adherent surface. The design parameters of mechanical systems for micro-application of adhesive resin is discussed.

This paper presents the characteristics of microapplication technology of adhesive resin by using a needle. The process of microapplication is experimentally investigated. The amount of adhesive resin on the needle is influenced by the shape and size of the needle. The microapplication of adhesive resin is dependent on the handling process of the needle to transfer adhesive resin on the adherent surface. The design guide of the mechanical systems for microapplication of adhesive resin is discussed.

We report recognition system for DNA tetraloops (dA1G2G3C4T5T6C7G8G9C10C11T12 (core) and dAGGCTTCGGCCT (AP2); X = abasic nucleotide) by peptides selected with combinatorial chemistry. As a result, peptides with Thr/Glu/His and Gln/Asp were obtained in binding of DNA core and AP2, respectively.