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Functional composite films made from lecithin micelles and the two heme proteins of met-myoglobin (Mb) and met-hemoglobin (Hb) are reported in this paper. Proteins in functional composite films have much higher rates of electron transfer than proteins in solutions on carbon paste (CP) electrodes. Cyclic voltammograms (CVs) all give a pair of well-defined and quasi-reversible peaks, corresponding to the heme FeIII/FeII redox couple of proteins. Differential pulse voltammograms (DPVs) also show the same formal potential ( E 0 ′ ) values of proteins under identical conditions. Electronic and vibrational spectra indicate that proteins in these films are not denatured, but their conformational differences from native states may exist. The E 0 ′ value for Mb in the lecithin film is found to be pH dependent. The Mb lecithin film can catalytically reduce O2 and H2O2, and its analytical application to H2O2 determination is established.

Direct electrochemistry of the myoglobin‐triacetone triperoxide (Mb‐TATP) composite on carbon paste (CP) electrode is reported. This electrode gives a well‐defined and quasi‐reversible cyclic voltammogram for the Mb FeIII/FeII redox coupled with the formal potential (E˚′) of −0.302 V (vs. Ag/AgCl) in pH 6.92 phosphate buffer. Electronic and vibrational spectroscopies show that the Mb in the composite retains a structure similar to its native form. The enzymatic reactivity to the reduction of H2O2 has been studied for the Mb‐TATP film. The analytical performances have been obtained with the linear range of 78.32–1135.64 µM, the detection limit of 55 µM (S/N=3), and the apparent Michaelis‐Menten constant (K m) of 662.8 µM. This H2O2 biosensor based on the electrocatalysis of the immobilized Mb presents a higher stability within two weeks.

To explore the relationship between the scores of episodic memory (EM) encoding and retrieving and the resting-state changes of brain functional connectivity (FC) network of Alzheimer's disease (AD) and mild cognition impairment (MCI) patients.All subjects were recruited from special care clinic and ward and health physical examination center, Qingdao Huanxiu Community and Affiliated Hospital, Medical College of Qingdao university from January 2009 to July 2012.They were divided into AD group (n = 16), MCI group (n = 24) and normal control (NC) group (n = 24). The resting-state fMRI scans were performed with GE3.0T to acquire the blood oxygenation level dependent signals for EM encoding and retrieving. The two-sample t test was conducted between the groups and linear correlation analysis performed between EM and FC.Compared to the NC group, the AD and MCI groups exhibited decreased FC to posterior cingulated cortex (PCC) mainly in bilateral lateral temporal lobe, medial prefrontal cortex and right insula.Increased regions existed in posterior cerebellar lobe. Compared with the MCI group, the AD group showed decreased FC to PCC in medial prefrontal cortex, bilateral insulas, right inferior temporal gyrus and right fusiform gyrus.And increased regions lied in posterior cerebellar lobe, right occipital lobe and left superior parietal lobule. Compared with the NC group, the MCI group exhibited decreased FC to PCC in left lingualis gyrus, left frontal lobe, right middle temporal gyrus and corpus callosum.And increased regions lied in posterior cerebellar lobe.EM encoding scores (%) (AD group 34 ± 20, MCI group 47 ± 17, NC group 69 ± 15) were significantly different among three groups (P0.05).And retrieving scores (%) (AD group 31 ± 18, MCI group 57 ± 22, NC group 81 ± 16) were significantly different among three groups (P0.05). Altered functional connectivity regions of left triangle orbital-inferior frontal gyrus (r = 0.642 98), left cuneus (r = 0.642 98) and left caudate nucleus (r = 0.642 68) showed positive correlations with the EM encoding scores in AD group (all P0.005). Other groups were not statistically significant.The resting-state FC networks of AD and MCI groups show significant differences. The MCI and AD patients have progressively decreased scores of episodic memory encoding and retrieving.And the declines of episodic memory encoding and partial regions of resting-state FC network are positively correlated in the AD group.

The title compound, C13H8Cl2N2, was prepared by reaction of ο-phenyl­enediamine with 2,4-dichloro­benzaldehyde under reflux in ethanol. The dihedral angle between the benzimidazole system and the benzene ring is 42.00 (15)°. In the crystal structure, intermolecular N—H⋯N inter­actions are present.

The title compound, C13H9ClN2, was prepared by reaction of o-phenyl­enediamine with 4-chloro­benzaldehyde under reflux in ethanol. The mol­ecules are linked by N—H⋯N inter­actions.

The title compound, C18H16N4O, was prepared by the reaction of 5-phenyl-1H-pyrazole-3-carbohydrazide with 4-methyl­benzaldehyde in refluxing ethanol. The structure exhibits weak inter­molecular N—H⋯O and N—H⋯N hydrogen-bonding inter­actions.

The title compound, C20H14Cl2N2, was prepared by reaction of o-phenyl­enediamine with 2-chloro­benzaldehyde under reflux in ethanol. The crystal structure is stabilized by van der Waals inter­actions.

The title compound, C11H15NOS, was prepared by the reaction of phenyl isothio­cyanate with isobutyl alcohol at room temperature. The central CNC(=S)O group is essentially planar. In the crystal structure, the mol­ecules are connected via N—H⋯S inter­actions.