Elastic constants in orthorhombic hen egg-white lysozyme crystals

The ultrasonic sound velocities of cross-linked orthorhombic hen egg-white lysozyme (HEWL) crystals, including a large amount of water in the crystal, were measured using an ultrasonic pulse-echo method. As a result, seven elastic constants of orthorhombic crystals were observed to be C11 = 5.24 GPa, C22 = 4.87 GPa, C12 = 4.02 GPa, C33 = 5.23 GPa, C44 = 0.30 GPa, C55 = 0.40 GPa, and C66 = 0.43 GPa, respectively. However, C13 and C23 could not be observed because the suitable crystal planes could not be cut from bulk crystals. We conclude that the observed elastic constants of the cross-linked crystals are coincident with those of the intrinsic crystals without cross-linking. Moreover, the characteristics of the elastic constants in orthorhombic HEWL crystals are due to the fact that the shear elastic constants, C44, C55, and C66, are softer than in tetragonal crystals. That is, the shear components, C44, C55, and C66, are one half of those of the tetragonal crystals.

Zahn infarct of the liver resulting from occlusive phlebitis in portal vein radicles

A 56-yr-old man had a solitary nodular mass in the right hepatic lobe. The nodule was clinically diagnosed as hepatocellular carcinoma, and a right hepatic lobectomy was performed. The nodule had a previously undescribed histological appearance, and was finally diagnosed as a Zahn infarct with the additional feature of fibrosis. We think that the mass was produced by occlusive phlebitis in a medium-size portal vein radicle and its smaller radicles. This is the case of a very unique Zahn infarct in two respects: 1) the histological appearance (fibrosis), and 2) the fact that it was due to occlusive phlebitis in portal vein radicles. The data obtained here indicate that a special type of Zahn infarct, as represented by this case, may present with clinical information (nodular mass and neovascularity) suggestive of hepatocellular carcinoma.

The detection and prognosis of small pancreatic carcinoma

During a period of 16 years, 203 proven pancreatic ductal adenocarcinomas were studied. Tumor size was measured on either the resected or the autopsy specimen. Four tumors were smaller than 1 cm, and 17 tumors were between 1.1 and 2 cm. ERCP has been found to be the most accurate in the diagnosis of small pancreatic carcinoma. Followup of 44 patients in whom the tumor was resected showed that survival depended on tumor size. In four patients with tumors smaller than 1 cm without parenchymal invasion, the postoperative 5-yr cumulative survival rate was 100%. Pancreatic carcinoma smaller than 1 cm limited to duct epithelium is considered as early cancer. Various diagnostic imaging modalities are now available to evaluate patients in whom pancreatic carcinoma is clinically suspected. These include ultrasonography (US), computed tomography (CT), endoscopic retrograde cholangiopancreatography (ERCP), and angiography. More recently magnetic resonance imaging (MRI), endoscopic ultrasound (EUS), and peroral pancreatic ductal biopsy also have been used. This report compares diagnostic modalities for pancreatic carcinoma in order to provide a data base for their rational use in the diagnosis of small resectable pancreatic carcinomas.

Transforming growth factor beta gene maps to human chromosome 19 long arm and to mouse chromosome 7

Transforming growth factors (TGF) are defined as biologically active polypeptides which reversibly confer the transformed phenotype onto untransformed cultured cells. They have been subdivided into two classes: type alpha and type beta TGFs. TGF-beta acts synergistically with TGF-alpha in inducing phenotypic transformation. TGF-beta can also act as a negative autocrine growth factor. A human 1050-bp EcoRi cDNA fragment was used to map the human locus for TGF-beta by Southern blotting of DNA prepared from 17 human X Chinese hamster somatic cell hybrids. The human-specific restriction fragments segregated with human chromosome 19 in all of 14 informative hybrids. All other human chromosomes were discordant with the TGF-beta bands in at least four hybrids. After in situ hybridization of the tritiated TGF-beta probe to normal human metaphase spreads, 151 silver grains were scored in 54 cells. Of 24 grains over chromosome 19, 16 grains (11%) lay over region 19q13.1----q13.3. Of the 54 cells analyzed, 16 (30%) had label over region 19q13.1----q13.3. Thus, TGFB is assigned to chromosome 19, subbands q13.1----q13.3. The Tgf-beta locus in the mouse was mapped to chromosome 7 by hybridizing a murine cDNA probe to a Chinese hamster X mouse hybrid panel. Human chromosome 19 and proximal mouse chromosome 7 share another four homologous loci.