The accuracy of color Doppler ultrasonography (CDUS) in diagnosing right hepatic artery (RHA) involvement was preoperatively evaluated in 28 patients with biliary tract cancer. When a tumor partially or completely surrounded the RHA, the circumferential involvement was diagnosed as positive. With B-mode ultrasonography imaging alone in the 10 nonsurgical patients, the correspondence rates with angiography for the presence of invasion, absence of invasion, and overall were 33%, 0%, and 10%, respectively. However, CDUS allowed clearer visualization of the RHA than did B-mode imaging, and the correspondence rates of CDUS with angiography were 100%, 43%, and 60%, respectively. In the 13 surgical patients, the accuracy levels of B-mode imaging, CDUS, computed tomography, and angiography for the detection of RHA involvement were 46%, 77%, 58%, and 92%, respectively, when compared with surgical and histopathologic findings. Although the accuracy of CDUS was lower than that of angiography, it can be performed repeatedly and noninvasively. CDUS is expected to be useful for the initial assessment of RHA involvement.

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Cross-linking of vitreous collagen and degradation of hyaluronic acid induced by bilirubin-sensitized photochemical reaction.

To determine the mechanisms of vitreous liquefaction following vitreous hemorrhage, we investigated the effects of the free radicals produced by a bilirubin-sensitized photochemical reaction on collagen and hyaluronic acid (HA). Bovine vitreous collagen and HA were irradiated by visible light in the presence of bilirubin, which is produced from the degradation of hemoglobin, as a photosensitizer. Changes in molecular weight were monitored by sodium dodecyl sulfate-polyacrylamide gel electrophoresis for the collagen, and high-performance liquid chromatography for the HA. We found that free radicals caused an increase in high-molecular-weight components and insolubilization of the vitreous collagen, and a decrease in the molecular weight of HA. The changed molecular properties of the vitreous collagen could be attributed to the extensive cross-linking of the molecules. This cross-linking and the degradation of HA, both induced by the bilirubin-sensitized photochemical reaction, may contribute to vitreous liquefaction following vitreous hemorrhage.

Animals↗

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Complementary DNA sequences of ovarian follicular fluid inhibin show precursor structure and homology with transforming growth factor-beta.

Inhibin, a specific and potent polypeptide inhibitor of the secretion of follicle-stimulating hormone (FSH), of gonadal origin and thus a potential contraceptive, may constitute a missing link in the mechanism controlling the differential secretion of the pituitary gonadotropins. Inhibin-like bioactivity has been reported in various fluids and extracts of testis and in ovarian follicular fluid. Although there have been several attempts to purify inhibin from seminal plasma, purification from follicular fluid has been more successful (refs 14-16; for review see ref. 17). We have previously isolated two forms (A and B) of inhibin from porcine follicular fluid. Each form comprised two dissimilar subunits of relative molecular mass (Mr) 18,000 (18K, referred to here as the alpha-subunit) and 14K (the beta-subunit), crosslinked by one or more disulphide bridge(s). Forms A and B differ in the N-terminal sequence of their 14K subunit. Preliminary structural characterization of porcine and bovine ovarian inhibins shows that they have similar properties. Here, we have used the N-terminal amino-acid sequence data on the subunits of each inhibin to identify cloned complementary DNAs encoding the biosynthetic precursors and report that inhibins are the product of a gene family that also includes transforming growth factor-beta (TGF-beta) and whose structural organization is similar to that of pituitary and placental glycoprotein hormones.

Amino Acid Sequence↗

PubMedDate not supplied

Pituitary FSH is released by a heterodimer of the beta-subunits from the two forms of inhibin.

Inhibin is a gonadal protein that specifically inhibits the secretion of pituitary follicle-stimulating hormone (FSH). Two forms of inhibin (A and B) have been purified from porcine follicular fluid and characterized as heterodimers of relative molecular mass (Mr) 32,000 (ref. 2). Each inhibin is comprised of an identical alpha-subunit of Mr 18,000 and a distinct but related beta-subunit of Mr 13,800-14,700 linked by interchain disulphide bond(s). Throughout the purification of inhibins, we consistently observed two fractions which stimulated the secretion of pituitary FSH. We report here the isolation of one of the FSH-releasing proteins; it has a Mr of 24,000 and its N-terminal sequences up to residue 32 are identical to those of each beta-subunit of inhibins A and B. In the presence of reducing agents, SDS-polyacrylamide gel electrophoresis resolves the FSH-releasing substance into two subunits which are identical in their migration behaviour to the reduced beta-subunits of inhibins A and B. Based on the N-terminal sequence data and Mr of the intact and reduced molecules, we propose that the FSH-releasing substance, which is active in picomolar concentrations, is a heterodimeric protein composed of the two beta-subunits of inhibins A and B linked by interchain disulphide bond(s). The structural organization of the FSH-releasing substance is homologous to that of transforming growth factor-beta (TGF-beta), which also possesses FSH-releasing activity in the same bioassay. We suggest that the substance be called activin to signify the fact that it has opposite biological effects to inhibin.

Amino Acid Sequence↗

PubMedDate not supplied

Angiotensinogen-producing hepatocellular carcinoma.

This paper describes the first case of an angiotensinogen-producing tumor. The tumor obtained from a hypertensive patient was examined for its renin and angiotensinogen contents. Renin activity was undetectable; however, the angiotensinogen level was extremely high compared with the levels in the tissue surrounding the hepatoma. The presence of angiotensinogen immunoreactivity in the tumor cells was demonstrated by immunohistochemical staining with an angiotensinogen anti-serum. The plasma level of angiotensinogen was also markedly elevated. These results strongly suggest that the hepatoma was an angiotensinogen-producing tumor.

Adult↗

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A hepatocellular carcinoma with lymph node metastasis and invasion into the gallbladder: preoperative difficulty ruling out a gallbladder carcinoma.

We present a case of resected hepatocellular carcinoma (HCC) which invaded the gallbladder with a metastasis to a lymph node. It was extremely difficult to make a differential diagnosis between HCC and gallbladder cancer preoperatively. A 68-year old man was admitted to hospital with complaint of a fever. Ultrasonography (US) and CT scan showed a mass, growing invasively from the gallbladder bed of the liver (S4) to the lumen of the gallbladder. A selective arteriography showed the mass stained by the cholecystic artery, internal branch of the left hepatic artery, and frontal branch of the right hepatic artery. Endoscopic retrograde cholangiopancreatography (ERCP) showed the non-visualized gallbladder, a constriction of the common hepatic duct with suspicion of metastatic lymph nodes in the hepatoduodenal ligament. The tumor markers were: alpha-fet-protein 13175 ng/ml, PIVKA-II 26200 mAU/ml and CA19-9 0.0 U/ml. Both HBs antigen and HCV antibody were negative. We performed cholecystectomy with en-block resection of the anterior and middle inferior segment of the liver, the common bile duct and a part of the transverse colon, with dissection of the lymph nodes. The tumor, 8 cm in diameter, was brown colored without a capsule, growing diffusely in the liver, to the inside of the gallbladder and the transverse colon. Histopathological inspection of the specimen revealed moderately differentiated hepatocellular carcinoma with a metastatic lymph node along the common hepatic artery. TNM classification was IVB phase [T3,N0,M1 (LYM,OTH)]. There are only 3 previous cases of HCC reported with invasion into the gallbladder. At most 2.2% of the resected cases of HCC had metastatic lymph nodes at resection, while it was as high as 20-50% of the autopsy cases. Operation on such an invasive HCC case should consider lymph node metastasis.

Aged↗

PubMedDate not supplied

A case of pancreatic serous cystadenoma obstructing the distal pancreatic duct.

We present a case of resected serous cystadenoma of the pancreas inducing marked dilatation of the main distal pancreatic duct. A 68-year-old woman, previously diagnosed with chronic pancreatitis, presented with upper abdominal pain. Abdominal US revealed a highly echoic mass in the pancreas. A CT scan disclosed a low density mass in the pancreas and dilatation of the main peripheral pancreatic duct. The mass demonstrated homogeneous and high signal intensity on T2-weighted magnetic resonance imaging (MRI). Selective abdominal arteriography showed the mass strained by the celiac artery. The tumor markers were CEA (2.4 ng/ml) and CA19-9 (6.1 U/ml). After the diagnosis of serous cystadenoma of the pancreas, the patient underwent distal pancreatectomy and splenectomy. The tumor (2.5 cm in diameter) consisted of grayish-white nodules and occupied the body of the pancreas. The tail of the pancreas was atrophic. Histopathological examination of the specimen showed a multilocular lesion containing numerous cysts with the inner surfaces evenly lined by one layer of cuboid or flat epithelial cells which stained positive for periodic acid-Schiff (PAS), evidencing serous cystadenoma. The patient is doing quite well one and a half years after the operation.

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