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Inhibition of Shaker K+ channel activity by external Na+ was previously reported in the melon (Cucumis melo L.) inwardly rectifying K+ channel MIRK and was hypothesized to contribute to salt tolerance. In this study, two inward Shaker K+ channels, CsKAT2 from cucumber (Cucumis sativus) and ClKAT2 from watermelon (Citrullus lanatus), were identified and characterized in Xenopus oocytes. Both channels were inwardly rectifying K+ channels with higher permeability to potassium than other monovalent cations and more active when external pH was acidic. Similarly to MIRK, their activity displayed an inhibition by external Na+, thus suggesting a common feature in Cucurbitaceae (Cucumis spp. Citrullus spp.). CsKAT2 and ClKAT2 are highly expressed in guard cells. After 24 h of plant treatment with 100 mM NaCl, the three KAT2 -like genes were significantly downregulated in leaves and guard cells. Reciprocal chimeras were obtained between MIRK and Na+-insensitive AtKAT2 cDNAs. The chimera where the MIRK S5-P-S6 segment was replaced by that from AtKAT2 no longer showed Na+ sensitivity, while the inverse chimera gained Na+ sensitivity. These results provide evidence that the molecular basis of the channel blockage by Na+ is located in the S5-P-S6 region. Comparison of the electrostatic property in the S5-P-S6 region in AtKAT2 and MIRK revealed four key amino acid residues potentially governing Na+ sensitivity. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the clinical and optical outcomes after clear corneal incision cataract surgery (CICS) with three different incision sizes (1.8, 2.0 and 3.0 mm)., Methods: Eyes of 150 patients with age-related cataract scheduled for coaxial cataract surgery were randomized to three groups: 1.8, 2.0, or 3.0 mm CICS. Intraoperative data and postoperative outcomes including surgically induced astigmatism (SIA), the corneal incision thickness, wavefront aberrations and modulation transfer function (MTF) of cornea were obtained., Results: There were no significant differences among the three groups in demographic characteristics and intraoperative outcome. The 1.8 and 2.0 mm microincisions showed more satisfactory clinical outcomes than the 3.0 mm incision. The 1.8 mm incision showed significantly less SIA than the 2.0 mm incision until postoperative 1mo (P<0.05), but the difference was only 0.14-0.18 D. Combined with less increased incision thickness only at postoperative 1d (P=0.013), the 1.8 mm incision presented better uncorrected distance visual acuity (UCDVA) than the 2.0 mm incision only at 1d postoperatively (P=0.008). For higher-order aberrations and other Zernike coefficients, there were no significant differences between the 1.8 mm group and 2.0 mm group (P>0.05)., Conclusion: Converting from 3.0 mm CICS to 1.8 or 2.0 mm CICS result in better clinical and optical outcomes. However, when incision is 1.8 mm, the benefits from further reduction in size compared with 2.0 mm are limited. The necessity to reduce the incision size is to be deliberated.

The title complex, [Co(C(10)H(9)N(4)O(2)S)(2)(C(3)H(7)NO)(2)], lies across an inversion center. The Co(II) atom is coordinated in a slightly distorted octa-hedral geometry by four N atoms from two bidentate 4-amino-N-(pyrimidin-2-yl)benzene-sulfonamidate (sulfadiazine) anions and two O atoms from two dimethyl-formamide (DMF) ligands. The dihedral angle between the benzene and pyrimidine rings is 82.37 (13)°. A three-dimensional network is generated by N-H⋯O hydrogen bonds between the amino groups and of the sulfonamidate O atoms of neighbouring mol-ecules. The DMF ligand is disordered over two sets of sites in a 0.559 (4):0.441 (4) ratio.

The asymmetric unit of the title compound, [Co(C(9)H(8)Cl(2)NO)(3)], contains three independent mol-ecules. In each mol-ecule, the Co(III) ion is coordinated by an O atom and an N atom from three bidentate 2,4-dichloro-6-(ethyl-imino-meth-yl)phenolate ligands in a slightly distorted octa-hedral environment. In the crystal, a weak C-H⋯Cl hydrogen bond is observed.

In the title complex, [Ni(C(9)H(9)BrNO)(2)], the Ni(II) ion lies on an inversion centre and is coordinated in a slightly distorted square-planar geometry by two N atoms and two O atoms from two symmetry-related bidentate 4-bromo-2-(ethyl-imino-meth-yl)phenolate ligands. The complex forms a one-dimensional chain in the crystal structure through short C-H⋯Br contacts (H⋯Br = 3.009 Å).