Ab initio methods are used to discover the effects of formaldehyde substituents on potential hypersurfaces for proton transfer in the equilibrium complex (ABCO-H-OCXH)+ in which A, B, and X are electronreleasing or -withdrawing groups. The potential profiles span the full range from symmetric double well, asymmetric double well, to single well, depending on the substituents. A symmetric double well corresponds to a complex with two equivalent subunits such as (FCHO-H-OCHF)', whereas in (HFCO-H-OCH?)' only one minimum structure is obtained in the entire potential surface. When the protonation energies of the two subunits are not greatly different an asymmetric double well might form. A ratio o to represent the extent of the difference of protonation energies between the two subunits in the complex was introduced to illustrate the formation of an asymmetric double well for calculated several complexes. To determine which conformation of the two wells has lower energy, the magnitude of the addition of binding energy of the conformation and the protonation energy of the subunit nearer the central proton is a crucial factor. The bigger is the magnitude of the conformation, the deeper is the well. A deeper right well in either the trans or cis conformer of (CH,FCHO-H-OCH*)'can be clarified easily with this magnitude as a parameter. It would be puzzling if only one term of energy (either binding energy of the conformation of two wells or protonation energy of the two subunits) were used. The difference of the magnitudes in two wells represents the potential gap between the two wells. The geometries of complexes varied from the parent complex (H2CO-H-OCH*)+ are discussed briefly based on the direction of the dipole moment in the substituted subunits. The thermodynamic properties AH', AS", and AGO of the association reaction ABCOH' + HXCO -(ABCO-H-OCXH)+ at several temperatures are evaluated according to standard thermodynamic formulae that incorporate the vibrational frequencies of the various species. IntroductionProton transfer involved in chemical and biological processes has been extensively investigated.Experimental measurements yielded a linear correlation between the bond dissociation energy and the difference between the proton affinities of the proton donor and of the proton acceptor.2 Blatz et al.' measured the concentrations of the H-bonded form and of the protontransferred form of a Schiff base quantitatively as a function of temperature through the absorbance of the species. Deuterium isotope fractionation6 in the gas phase of proton-transfer reactions between DO-and substituted 2-propenes have also been measured. Quantum chemical calculations were employed to supplement the experimental work; this approach has the advantage that it yields both energies and structures of the intermediates and transition states. Such a calculation supplies directly the activation energies and is independent of a dynamic model to correlate rates withThe transition structures and energy barriers of intramolecular proton transfe...

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Hidradenitis suppurativa is a cutaneous chronic inflammatory disease that is estimated to affect about 1% of the population and caused pain, malodorous discharge, disfigurement, and poor quality of life with psychosocial problems. The typical features are recurrent painful nodules, abscesses, and sinus tracts on the axillae, groins, gluteal areas, and anogenital regions since postpuberty. Smoking and obesity are two major triggering factors of hidradenitis suppurativa. Women are prone to have hidradenitis suppurativa than men in Western countries, but the male-to-female ratio is reversed in oriental countries. The disease severity can be affected by menstruation, pregnancy, and menopause. Furthermore, the phenotypes are different among men and women with hidradenitis suppurativa. Men are prone to have buttock involvement while women are prone to have axillary, groins, and submammary lesions. This review introduces the skin appendages and pathophysiology of hidradenitis suppurativa and then focuses on the sex difference and the effects of sex hormones on hidradenitis suppurativa and current hormone-associated treatments.

Psoriasis in different body regions displays varying therapeutic responses to biologics, whereas currently relevant studies remain scarce. We retrospectively reviewed the treatment responses of patients with moderate-to-severe psoriasis, who completed the two-year reimbursed ustekinumab or secukinumab treatment in two medical centers in Southern Taiwan. Demographic profiles and body regional PASI scores (head/neck, trunk, upper and lower limbs) along the treatment course were recorded. The proportions of patients attaining PASI 75, 90, 100 and the extent of body regional PASI score improvements were compared in biologic naïve or experienced patients. A total of 57 and 67 patients receiving ustekinumab and secukinumab injections, respectively, were included. Overall, patients receiving secukinumab showed higher degrees of PASI score improvements along the two-year treatment course. The lower limbs had the highest, and the upper extremities and head/neck