Second hepatectomy for recurrent hepatocellular carcinoma achieved sustained virological response to interferon therapy for hepatitis C.

BACKGROUND/AIMS: Interferon (IFN) improves the prognosis of HCV-related hepatocellular carcinoma (HCC) in patients. However, the effects of IFN therapy for second hepatectomy (Hx) for recurrent HCC have not been established. METHODOLOGY: Subjects included 96 patients who underwent a second Hx for recurrence of HCV-related HCC. Forty-four patients received IFN therapy past or postoperatively of the first Hx. Twenty of those patients attained a sustained viral response (SVR). The other 24 were non-responders (NR) and 52 patients who had not received IFN therapy (non-IFN) were classified as the NR/non-IFN group. RESULTS: Overall survival (SVR group vs. NR/non-IFN group: 5-yr, 91.7 vs. 51.0%; p = 0.012) and disease-free survival (SVR group vs. NR/non-IFN group: 3-yr, 64.7 vs. 25.9%; p = 0.006) rates were significantly different in both groups. By multivariate analysis, NR/non-IFN therapy, was the independent risk factor for overall survival (p = 0.025) and disease-free survival (p = 0.006) after second Hx. CONCLUSIONS: SVR achieved past or postoperatively of the first Hx of HCV-related HCC significantly inhibits recurrence and consequently improves patient survival after second Hx for recurrent HCC. Patients with SVR to IFN therapy would be good candidates for second Hx for recurrent HCC.

Morphological and functional characterization of a novel Na+/K+-ATPase-immunoreactive, follicle-like structure on the gill septum of Japanese banded houndshark, Triakis scyllium.

In teleost fishes, it is well-established that the gill serves as an important ionoregulatory organ in addition to its primary function of respiratory gas exchange. In elasmobranch fish, however, the ionoregulatory function of the gills is still poorly understood. Although mitochondria-rich (MR) cells have also been found in elasmobranch fish, these cells are considered to function primarily in acid-base regulation. In this study, we found a novel aggregate structure made up of cells with basolaterally-expressed Na(+)/K(+)-ATPase (NKA), in addition to NKA-immunoreactive MR cells that have already been described in the gill filament and lamella. The cell aggregates, named follicularly-arranged NKA-rich cells (follicular NRCs), were found exclusively in the epithelial lining of the venous web in the cavernous region of the filament and the inter-filamental space of the gill septum. The follicular NRCs form a single-layered follicular structure with a large lumen leading to the external environment. The follicular NRCs were characterized by: (i) well-developed microvilli on the apical membrane, (ii) less prominent infoldings of the basolateral membrane and (iii) typical junction structures including deep tight junction between cells. In addition, large numbers of vesicles were observed in the cytoplasm and some of them were fused to the lateral membrane. The follicular NRCs expressed Na(+)/H(+) exchanger 3 and Ca(2+) transporter 1. The follicular NRCs thus have the characteristics of absorptive ionoregulatory cells and this suggests that the elasmobranch gill probably contributes more importantly to body fluid homeostasis than previously thought.

Subcellular distribution of urea transporter in the collecting tubule of shark kidney is dependent on environmental salinity.

In the kidney of marine elasmobranchs, urea reabsorption from filtered urine is essential for maintaining high levels of urea in the body. In the kidney of the houndshark, Triakis scyllium, we previously found that a facilitative urea transporter (UT) is localized to a specific nephron segment, the collecting tubule, suggesting that the collecting tubule has an important role in the urea reabsorption process. To elucidate the roles of UT, we transferred T. scyllium to high (130%) and low (30%) salinity, and examined UT mRNA levels and UT distribution patterns in the kidney using real-time PCR and semi-quantitative fluorescence immunohistochemistry, respectively. Following transfer to low and high salinity, houndshark decreased and increased plasma urea concentrations, respectively, in order to control plasma osmolality. The abundance of UT mRNA did not differ among the experimental groups, whereas that of UT protein in the collecting tubule was significantly decreased in 30% seawater (SW). Furthermore, the subcellular UT distribution was dramatically changed. UT in the apical plasma membrane of collecting tubule almost disappeared in 30% SW, whereas it slightly increased in 130% SW compared with 100% SW. Conversely, reverse transfer of fish from 30 to100% SW restored UT in the apical membrane. These results indicate that the accumulation of UT to the apical plasma membrane of the collecting tubule of Triakis is an important factor for regulating urea reabsorption in the kidney.