Comprehensive elucidation of resting-state functional connectivity in anorexia nervosa by a multicenter cross-sectional study.

BACKGROUND: Previous research on the changes in resting-state functional connectivity (rsFC) in anorexia nervosa (AN) has been limited by an insufficient sample size, which reduced the reliability of the results and made it difficult to set the whole brain as regions of interest (ROIs). METHODS: We analyzed functional magnetic resonance imaging data from 114 female AN patients and 135 healthy controls (HC) and obtained self-reported psychological scales, including eating disorder examination questionnaire 6.0. One hundred sixty-four cortical, subcortical, cerebellar, and network parcellation regions were considered as ROIs. We calculated the ROI-to-ROI rsFCs and performed group comparisons. RESULTS: Compared to HC, AN patients showed 12 stronger rsFCs mainly in regions containing dorsolateral prefrontal cortex (DLPFC), and 33 weaker rsFCs primarily in regions containing cerebellum, within temporal lobe, between posterior fusiform cortex and lateral part of visual network, and between anterior cingulate cortex (ACC) and thalamus (p < 0.01, false discovery rate [FDR] correction). Comparisons between AN subtypes showed that there were stronger rsFCs between right lingual gyrus and right supracalcarine cortex and between left temporal occipital fusiform cortex and medial part of visual network in the restricting type compared to the binge/purging type (p < 0.01, FDR correction). CONCLUSION: Stronger rsFCs in regions containing mainly DLPFC, and weaker rsFCs in regions containing primarily cerebellum, within temporal lobe, between posterior fusiform cortex and lateral part of visual network, and between ACC and thalamus, may represent categorical diagnostic markers discriminating AN patients from HC.

Hydrogen-bonded six-component assembly for capsule formation based on tetra(4-pyridyl)cavitand and isophthalic acid linker and its application to photoresponsive capsule.

Two molecules of tetra(4-pyridyl)cavitand 1 and four molecules of isophthalic acid linker 2a with a triethylene glycol monomethyl ether (TEG) group self-assembled into a six-component capsule 12·2a4 through eight pyNHO2C hydrogen bonds, which encapsulates one molecule of guest G such as bis(4-acetoxyphenyl)acetylene and hexakis(4-iodophenyl)benzene to form G@(12·2a4). Guest-encapsulation ability and selectivity of 12·2a4 were revealed. trans-5-(p-Substituted-phenylazo)isophthalic acid with two dichotomous branching TEG groups trans-2b serves as a photoresponsive linker to form 12·(trans-2b)4, which moderately reduced guest-encapsulation ability upon photoisomerization (at the photostationary state, 10% guest release upon subunit-trans-2b/subunit-cis-2b = 18 : 82).

Encapsulation-induced remarkable stability of a hydrogen-bonded heterocapsule.

Remarkably enhanced stability of the self-assembled hydrogen-bonded heterocapsule 1⋅2 by the encapsulation of 1,4-bis(1-propynyl)benzene 3 a was found with Ka =1.14×10(9) M(-1) in CDCl3 and Ka2 =1.59×10(8) M(-2) in CD3 OD/CDCl3 (10 % v/v) at 298 K. The formation of 3 a@(1⋅2) was enthalpically driven (ΔH°<0 and ΔS°<0) and there was a unique inflection point in the correlation between ΔH° versus ΔS° as a function of polar solvent content. The ab initio calculations revealed that favorable guest-capsule dispersion and electrostatic interactions between the acetylenic parts (triple bonds) of 3 a and the aromatic inner space of 1⋅2, as well as less structural deformation of 1⋅2 upon encapsulation of 3 a, play important roles in the remarkable stability of 3 a@(1⋅2).

Mechanism of orientational isomerism of unsymmetrical guests in a heterodimeric capsule: analysis by ab initio molecular orbital calculations.

The geometries and interaction energies of the heterodimeric capsule [tetrakis(4-hydroxyhphenyl)-cavitand 1 and tetra(4-pyridyl)-cavitand 2] complexes with methyl p-acetoxybenzoate 3, methyl p-ethoxybenzeoate 4, and p-ethoxyiodobenzene 5 were studied by ab initio molecular orbital calculations. The optimized structures and charge distributions of the complexes suggest that the electrostatic interactions of oxygen atoms in the guest molecules with the hydrogen atoms of aromatic rings and methylene-bridge rim in the heterodimeric capsule stabilize the complexes. The calculated relative energies of the two orientational isomers of the complexes well reproduce the experimentally observed orientational selectivity of the guest molecules. The calculated stabilization energies for the major orientational isomers of the heterodimeric capsule (1.2) complexes with guest molecules (3, 4, and 5) are -21.6, -19.6, and -19.4 kcal/mol, respectively. Those for the minor orientational isomers are 1.5, 3.5, and 3.7 kcal/mol smaller (less negative), respectively. The magnitude of the calculated energy differences agrees well with the order of the experimental population of the major orientational isomer (3 < 4 approximately 5). The large electron correlation contributions to the attraction (-27.0 to -31.8 kcal/mol) show that the dispersion interactions are the major source of the attraction in the complexes, while the electrostatic interactions (-4.9 to -12.5 kcal/mol) are also an important source of the attraction. Although the electrostatic interactions are weaker than the dispersion interactions, the highly orientation dependent electrostatic interactions mainly determine the orientation of the unsymmetrical guest molecules in the complexes. The electrostatic interactions in the major orientational isomer are 2.6-3.9 kcal/mol larger (more negative) than those in the minor orientational isomer, while the differences of other energy terms are small (less than 1.1 kcal/mol). The interaction energies calculated for model complexes show that the CH/pi interactions are not playing important roles in controlling the orientation of the guest molecules in the complexes.

Molecular recognition and self-assembly special feature: Encapsulated-guest rotation in a self-assembled heterocapsule directed toward a supramolecular gyroscope.

The self-assembled heterocapsule 1.2, which is formed by the hydrogen bonds of tetra(4-pyridyl)-cavitand 1 and tetrakis(4-hydroxyphenyl)-cavitand 2, encapsulates 1 molecule of guests such as 1,4-diacetoxybenzene 3a, 1,4-diacetoxy-2,5-dimethylbenzene 3b, 1,4-diacetoxy-2,5-dialkoxybenzenes (3c, OCH(3); 3d, OC(2)H(5); 3e, OC(3)H(7); 3f, OC(4)H(9); 3g, OC(5)H(11); 3h, OC(6)H(13); 3i, OC(8)H(17)), 1,4-diacetoxy-2,5-difluorobenzene 4a, and 1,4-diacetoxy-2,3-difluorobenzene 4b. The X-ray crystallographic analysis of 3c@(1.2) showed that the acetoxy groups at the 1,4-positions of 3c are oriented toward the 2 aromatic cavity ends of 1.2 and that 3c can rotate along the long axis of 1.2. Thus, the 1.2 (stator) with the encapsulation guest (rotator) behaves as a supramolecular gyroscope. A variable temperature (VT) (1)H NMR study in CDCl(3) showed that 3a, 3b, 4a, and 4b within 1.2 rotate rapidly even at 218 K, whereas guest rotation is almost inhibited for 3h and 3i even at 323 K. In this respect, 4b with a large dipole moment is a good candidate for the rotator of 1.2. For 3c-3g, the enthalpic (DeltaH(double dagger)) and entropic (DeltaS(double dagger)) contributions to the free energy of activation (DeltaG(double dagger)) for the guest-rotational steric barriers within 1.2 were obtained from Eyring plots based on line-shape analysis of the VT (1)H NMR spectra. The value of DeltaG(double dagger) increased in the order 3c < 3d < 3e < 3f < 3g. Thus, the elongation of the alkoxy chains at the 2,5-positions of 3 puts the brakes on guest rotation within 1.2.