Dedifferentiated liposarcoma with chondroblastic osteosarcomatous dedifferentiation

We describe a rare case of dedifferentiated liposarcoma with features resembling chondroblastic osteosarcoma in the dedifferentiated component. The tumor was removed from the left thigh in a 78-year-old male. It consisted of a well-differentiated liposarcoma and an anaplastic component that contained numerous osteoid and cartilaginous tissues surrounded by high-grade spindle cell sarcoma. To our knowledge, only two cases similar to the divergent chondroblastic osteosarcomatous dedifferentiation of this disease have been reported in the literature.     

The chitosan prepared from crab tendon I: the characterization and the mechanical properties

Crystalline chitosan was prepared from crab tendon consisting mainly of chitin, including various proteins and calcium phosphates. The crab tendon has high mechanical properties due to its aligned molecular structure. Crab tendon components, i.e. proteins and calcium phosphates, were removed by deacetyl treatment using 50wt% NaOH aqueous solution at 100 degrees C, and a subsequent ethanol treatment. As judged from microscopic observations using an optical polarizer, the treated chitosan remained intact regarding its aligned molecular structure, and had a high tensile strength of 67.9+/-11.4MPa. The tensile strength was further enhanced to 235+/-30MPa by a thermal treatment at 120 degrees C, corresponding to the formation of the intermolecular hydrogen bonds.     

Feasibility of using decades-old archival tissues in molecular oncology/epidemiology.

Archival tissues are a bountiful resource for various studies. Polymerase chain reaction permits the use of such tissues for molecular biological analyses of disease causation. However, a comprehensive study using a large number of decades-old samples (20 or more years) for molecular oncology/epidemiology has never been shown to be feasible. We have relied upon the unique tumor registry of atomic bomb survivors to show that such studies are possible using 275 hepatocellular carcinoma and 41 skin cancer cases. We used 23 relatively recent thyroid papillary carcinoma cases from persons living in the vicinity of the Chernobyl nuclear reactor accident for comparison. Degradation of DNA is severe in autopsy hepatocellular carcinoma samples but can be compensated for by decreasing the polymerase chain reaction product size. Increasing the amount of DNA that is used by a factor of 8 improved amplification efficiency from approximately 60 to 80%. Age of the samples was not as great a problem as was the source of procurement. The extracted DNA can be used for all types of assays that require polymerase chain reaction amplification, such as restriction fragment length polymorphism, single-strand conformation polymorphism, and direct sequencing.     

Tuning of the porin expression under anaerobic growth conditions by his-to-Asp cross-phosphorelay through both the EnvZ-osmosensor and ArcB-anaerosensor in Escherichia coli

BACKGROUND: Widespread bacterial signal transduction circuits are generally referred to as 'two-component systems' or 'histidine (His)-to-aspartate (Asp) phosphorelays.' In Escherichia coli, as many as 30 distinct His-to-Asp phosphorelay signalling pathways operate in response to a wide variety of environmental stimuli, such as medium osmolarity and anaerobiosis. In this regard, it is of interest whether or not some of them together constitute a network of signalling pathways through a physiologically relevant mechanism (often referred to as 'cross-regulation'). We have addressed this issue, with special reference to the osmo-responsive EnvZ and anaero-responsive ArcB phosphorelay signalling pathways in E. coli. RESULTS: Under standard aerobic growth conditions, it is well known that the osmoregulatory profile of the outer membrane porins (OmpC and OmpF) is mainly regulated by the EnvZ-OmpR phosphorelay system in response to medium osmolarity. In this study, it was found that, under anaerobic growth conditions, E. coli cells exhibit a markedly altered expression profile of OmpC and OmpF This profile was significantly different from that observed for the cells grown aerobically. Results from extensive genetic studies showed that, under such anaerobic growth conditions, the arcB gene encoding the anaero-sensory His-kinase appears to be an auxiliary genetic determinant that regulates the expression profile of porins. We then provided several lines of in vivo and in vitro evidence, which taken together, supported the following conclusions. CONCLUSIONS: Under anaerobic growth conditions, porin expression is tuned not only by the authentic osmo-resposive EnvZ sensor, but also by the anaero-responsive ArcB sensor, in an OmpR-dependent manner. It is suggested that such ArcB-mediated cross-regulation plays a physiological role by integrating anaerobic respiratory signals into the porin regulation in E. coli anaerobiosis. The proposed model is a clear example of the interplay of two distinct His-to-Asp phosphorelay signalling pathways.     

Parosteal fasciitis of the clavicle

A rare case of parosteal fasciitis arising from the periosteum of the left clavicle in a 27-year-old woman is reported. Magnetic resonance imaging demonstrated the lesion surrounding the periosteum of the clavicle. The lesion was iso-intense with muscle on T(1)-weighted images and hyperintense on T(2)-weighted images. At surgery, the lesion was discovered to be densely adherent with the periosteum, and excised along with the periosteum. Histopathological examination revealed the proliferation of myofibroblasts in a vague storiform or short fascicular pattern. A large amount of extravasated erythrocytes, and a few lymphocytes were present in the matrix. There were some foci of abundant myxoid materials. Immunohistochemical study showed the cells to be positive for vimentin, alpha-smooth muscle actin and HHF35, but negative for desmin. There was no local recurrence at a 6 months postoperative follow up.     

Virus-associated hemophagocytic syndrome: the diagnostic usefulness of immature histiocytes with benign features in the bone marrow

A 2-year-old girl developed fever, hepatosplenomegaly, jaundice, lymphadenopathy and pancytopenia. Bone marrow examination revealed increased immature histiocytes (5.5%) and mature histiocytes with hemophagocytosis. All the abnormalities were normalized in one month without any chemotherapy. It was suggested that the presence of immature histiocytes with benign features, even if their number exceeds that of mature histiocytes, does not favor the diagnosis of malignant histiocytosis.     

Age- and sex-related changes in toluene metabolism by rat hepatic microsomes in vitro

Age- and sex-related changes in toluene metabolism by hepatic microsomes of male and female Sprague-Dawley (SD) rats (1 to 20 weeks) were investigated. A major metabolite of toluene, benzyl alcohol (BA), was measured by high-performance liquid chromatography (HPLC). At low substrate toluene concentrations (0.4 mM), in male rats, BA increased dramatically with development, reaching a peak at 5 weeks of age, rapidly decreasing thereafter. In female rats, BA increased dramatically with development at 3 to 5 weeks of age, and then declined gradually to a low level. Gender differences were obtained at 5 and 20 weeks of age, with BA products being higher in males than in females. At high substrate toluene concentrations (5.0 mM), in male rats, the BA formation pattern was similar to that at the low substrate concentration, although the rate of increase with age was slower. In female rats, a peak was obtained at 3 weeks of age, and then declined gradually to a low level. Gender differences were obtained at 5, 15 and 20 weeks of age, with BA products being higher in males than in females. These results indicate that toluene metabolism exhibits age and gender differences.     

Effect of long-term administration of 1,2,3,4-tetrahydroisoquinoline (TIQ) on striatal dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) content in mice

Effects of long-term administration of 1,2,3,4-tetrahydroisoquinoline (TIQ) on the striatal dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) were investigated in mice and rats. Striatal dopamine content significantly increased and DOPAC decreased after repeated administrations of TIQ at a dose of 50 mg/kg/day s.c. for 70 days in mice. In contrast, dopamine and DOPAC content did not show any significant change in rats. The ratio DOPAC/dopamine decreased significantly in mice treated with TIQ for 70 days. The results presented suggest that TIQ reduces the turnover rate of the nigrostriatal dopamine neurons after repeated administration for a long period in mice.     

Morphological evidence for axonal sprouting of cerebellothalamic neurons in kittens after neonatal hemicerebellectomy

Summary Changes in cerebellothalamic projections in kittens after neonatal hemicerebellectomy were studied by the retrograde and anterograde horseradish peroxidase (HRP)-tract-tracing methods. The number of cerebellar nuclear neurons labeled retrogradely with HRP injected into the ipsilateral VA-VL complex of the thalamus was much more numerous in neonatally hemicerebellectomized kittens than in intact kittens. Presumed terminals of ipsilateral cerebellothalamic fibers labeled anterogradely with HRP injected into the cerebellar nuclei were also distributed more densely and extensively in the thalamic areas, especially in the VA-VL complex, of hemicerebellectomized kittens than in the thalamic areas of the control kittens. These results are in good accordance with those obtained from the previous electrophysiological study (Kawaguchi et al., 1979) and offer corroborating evidence for axonal sprouting of cerebellothalamic neurons after neonatal hemicerebellectomy.     

DETECTION OF HBsAg IN THE PANCREAS

Hepatitis B surface antigen (HBsAg) has been reported to be present in other organs than the liver.^3,9 So far as our knowledge is concerned, however, any report of cases dealing with pancreatic diseases induced by hepatitis B virus (HBV) has not been described in the English and Japanese literature. We report an autopsy case with a pancreatic lesion characterized by damage of both exocrine and endocrine epithelial cells with inflammatory response, which were immunohistochemically found to be positive for HBsAg, and electron-microscopically to possess core-like particles In the nucleus and cytoplasm.