Robot-assisted Partial Nephrectomy With Selective Artery Clamping for Renal Cell Carcinoma in Horseshoe Kidney.

BACKGROUND: Robot-assisted partial nephrectomy (RAPN) has become the standard treatment for small renal tumors, including highly complex cases. However, applying RAPN to renal tumors in the horseshoe kidney (HSK) is clinically challenging due to malformations and complex blood supply. Herein, we present two cases of RAPN in patients with HSK treated using selective artery clamping methods. CASE REPORTS: A 61-year-old male with a 15 mm renal tumor located on the upper pole of the right HSK was referred to our Department. The patient underwent RAPN via the transperitoneal approach, following a three-dimensional computed tomography (3D-CT) assessment. Additionally, before surgery, we confirmed which renal arteries would be clamped in surgery by examining the kidney regions supplied by each renal artery. The second patient referred to our Department, a 45-year-old male, had a 46 mm renal tumor located on the isthmus of the HSK. His tumor received blood supply from two renal arteries, with the bilateral collecting systems converging and forming a ureter on 3D-CT. The patient underwent RAPN through an intraperitoneal approach in the semi-lateral position, with port placement lower than in standard RAPN. Pathological examinations revealed clear-cell renal cell carcinoma with negative surgical margins in both cases. Both patients had no recurrences or metastases at 53 and 13 months post-surgery, respectively. CONCLUSION: We present cases successfully treated with RAPN with selective artery clamping methods for HSK using 3D-CT without encountering complications, even in isthmus tumors.

Activation of platelets upon contact with a vitamin E-coated/non-coated surface.

The purpose of this study was to determine the effects of a vitamin E-coated surface on platelet activation, focusing on the interactions among the vitamin E-coated surface, platelets and leukocytes. Platelet-rich plasma (PRP) or PRP containing leukocytes (LPRP) was used. No difference was observed in platelet activation between PRP and LPRP for a vitamin E-coated membrane, meaning that platelet activation triggered by leukocytes was suppressed in plasma coming in contact with a vitamin E-coated membrane, while the membrane itself directly induced platelet activation. The antioxidant capacity of the vitamin E-coated membrane in contact with PRP or LPRP was partially reduced, but sufficient residual capacity remained. The in vitro experiments using an oxidized vitamin E-coated surface revealed that P-selectin expression and superoxide anion production in the platelets and platelet adhesion were induced by contact with the oxidized vitamin E-coated surface. We conclude that contact with a vitamin E-coated surface reduces platelet activation mediated by superoxide anions, probably by reducing superoxide anions, but during the process of the reduction, the vitamin E-coated surface itself becomes oxidized, which again causes platelet activation. The beneficial effects of a vitamin E-coated dialyzer in respect of platelet activation were counteracted by the formation of oxidized vitamin E.

Structural, optical, and electronic properties of a series of 3,4-propylenedioxythiophene oligomers in neutral and various oxidation States.

A series of 3,4-propylenedioxythiophene (ProDOT) oligomers (nP(Hex)) with dihexyl side chains and methylthio end-capping units was synthesized as a model of poly(3,4-alkylenedioxythiophene)s. The slope of the linear relationship between the energy of the absorption maxima of nP(Hex) in the neutral states and the reciprocal of the number of monomer units (1/n) was found to be comparable to that of 3,4-ethylenedioxythiophene (EDOT) oligomers, suggesting that both the ProDOT and the EDOT oligomers have a similar effective conjugation. In cyclic voltammetry measurements, both the first and second oxidation waves and the third and fourth waves were shown to merge into one peak with increasing chain length. The stepwise chemical oxidations of nP(Hex) with SbCl(5) in CH(2)Cl(2) at room temperature gave their stable cationic species in various oxidation states, and it was found that only the radical cations (polarons) have an obvious absorption band in the visible region. Interestingly, when the absorption spectra of tetramer radical cation 4P(Hex)(+·) were measured at low temperatures, reversible disproportionation into dication 4P(Hex)(2+) and neutral species 4P(Hex) was observed in addition to π-dimer formation. Furthermore, the radical cations of the longer oligomers showed only the disproportionation reaction. From the comparisons of the results of experiments and the theoretical calculations of the dications, 6P(Hex)(2+) was found to have a closed-shell nature, and only a weak singlet biradical character appeared even in longer oligomers 10P(Hex)(2+) and 12P(Hex)(2+). Overall, the electron-donating dioxy substituents are considered to stabilize high p-doping levels with closed-shell dication (bipolaron) structures in poly(3,4-alkylenedioxythiophene)s, which enables the transparency properties of the polymers.