Deciphering the DNA repair protein, Rad23 from kuruma shrimp Marsupenaeus japonicus: full-length cDNA cloning and characterization.

AIMS: Lesions of DNA are removed by nucleotide excision repair (NER) process in the living systems. NER process-related host factors are believed to aid recovery steps during viral integration. Here, we report identification and characterization of a DNA repair molecule Rad23 from kuruma shrimp Marsupenaeus japonicus. METHODS AND RESULTS: The full-length cDNA of M. japonicus Rad23 gene (MjRad23) has 1149 bp coding for a putative protein of 382 amino acids with a 5' untranslated region (UTR) of 92 bp and 3' UTR region of 1116 bp. Quantitative expression analysis revealed MjRad23 is constitutively expressed in all the organs of healthy shrimp, whereas with high level in muscle tissue. Although MjRad23 expression is observed in every haemolymph samplings to post-white spot syndrome virus infection, high expression is recorded at 2 h post infection (h.p.i.). MjRad23 consists of putative functional domains including one ubiquitin domain (UBQ), two ubiquitin-associated domains (UBA) and one heat-shock chaperonin-binding motif (STI1). Multiple alignment of MjRad23 with Rad23 of other species showed highly significant identity ranging from 37 to 53%; however, high homology is observed with Rad23 of Bombyx mori (BmRad23). UBQ domain region alignment revealed maximum of 66% homology with Rad23 of Apis melifera (AmRad23). MjRad23 clustered with invertebrate sector along with insect species in evolution analysis. Three-dimensional structural analyses demonstrated the highest identity between MjRad23 and human Rad23A (hHR23A). CONCLUSIONS: The present work revealed the presence of MjRad23 gene, which is essential in DNA repair process. Further studies are required to clarify the involvement of MjRad23 in NER process. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report on identification and characterization of DNA repair protein in crustaceans, which will lead to further investigation to explore the molecular mechanisms behind the NER process.

Clinical abnormalities in adults with pancreaticobiliary maljunction with and without bile-duct dilatation.

OBJECTIVE: To study clinical diseases associated with pancreaticobiliary maljunction with or without bile-duct dilatation. DESIGN: A retrospective study over 16 years. SETTING: A single university surgical service in Japan. PATIENTS: Thirty-three patients with pancreaticobiliary maljunction. MAIN OUTCOME MEASURES: Gallstones and cancer in patients with and without bile-duct dilatation. RESULTS: Twenty-five patients had dilatation of the bile duct, 8 did not. Seven (28%) of the 25 patients with bile-duct dilatation had gallstones compared with 1 (12%) of the 8 patients with no dilatation. Seven (88%) of the 8 patients with no dilatation had carcinoma (all of the gallbladder), but only 3 (12%) of the 25 patients with bile-duct dilatation had carcinoma (1 of the gallbladder, 2 of the bile duct). CONCLUSION: Prophylactic cholecystectomy is recommended for patients with pancreaticobiliary maljunction and no dilatation of the bile duct because of the high incidence of gallbladder cancer.

Cancer of the gallbladder associated with anomalous junction of the pancreatobiliary duct system without bile duct dilatation.

The aim of this study was to delineate clinical features and prognosis of cancer of the gallbladder associated with anomalous junction of the pancreatobiliary duct system without bile duct dilatation, and to determine methods for managing the disease. A retrospective study of seven patients is presented. A further 27 cases from the Japanese literature were reviewed retrospectively with regard to method of treatment and prognosis. In 11 of 18 patients in whom staging was known the tumour was stage V, representing advanced disease. In seven of 34 cases curative operation was performed; only two patients survived for > 3 years. This poor outcome was due largely to delayed diagnosis of cancer of the gallbladder. Prophylactic cholecystectomy is recommended in patients with this anomalous junction without bile duct dilatation or a malignant lesion in the gallbladder, because of the high incidence of cancer of the biliary tract.

A new animal model for split liver transplantation using an infrahepatic IVC graft.

An animal model of split liver transplantation using pigs is described herein. The donor liver was divided into two grafts, the right graft consisting of the right medial and lateral segments with the caudate lobe, and the left graft consisting of the left lateral and medial segments. To make implantation easier, a distal part of the donor's inferior vena cava (IVC) was isolated and attached to the left graft with an anastomosis between the orifice of the renal vein and the graft's hepatic vein. The left graft thereby contained a newly constructed retrohepatic IVC for anastomosis to the recipient. During the anhepatic phase, no conventional bypass procedure was used, but an abdominal aortic clamp in combination with general hypothermia was employed. Ten pigs were used as donors and a total 20 liver transplantations performed. No immunosuppressive drugs were given in this series. Ten of the 20 recipients survived for more than 2 days, the mean survival time being 4.7 days, with a range of 2-14 days. The mean survival time of the left grafts was much longer than that of the right grafts, although no technical problems such as kinking of the graft or occlusion of the hepatic vein were encountered in either. This model is the first report of split liver transplantation in animals. The advantages of using the infrahepatic IVC graft include stability of the graft and safe hepatectomy. This model will therefore be useful for the experimental study of split liver transplantation and may also be employed for clinical use in the future.