Thoracic duct cyst in supraclavicular region.

A 28-year-old female attended an outpatient clinic in October, 1989, because of a tumor in the left supraclavicular fossa, detected in a health examination. Following exploratory puncture of the tumor which yielded milky-white fluid, suggesting a cyst in the thoracic duct, she was admitted to our department. The cyst was unilocular measuring about 6 cm in diameter, and the fluid content was chyle-rich in lipids. Lymphography demonstrated a lymphatic structure adjacent to the lesion and scattered lymph vessels on the cyst surface. On November 16 the cyst was resected. A restiform structure was observed between the cyst and the thoracic duct, but the presence or absence of communication was unclear. The histological diagnosis was thoracic duct cyst. Thoracic duct cyst occurring in the cervical region is very rare. Our case may provide useful information as to its pathogenesis and the mode of retention of cyst fluid.     

Genomic structure around joining segments and constant regions of swine T-cell receptor alpha/delta (TRA/TRD) locus

A complete genomic region of 131.2 kb including the swine T-cell receptor alpha/delta constant region (TRAC/TRDC) and joining segments (TRAJ/TRDJ) was sequenced. The structure of this region was strikingly conserved in comparison to that of human or mouse. All of the 61 TRAJ segments detected in the human genomic sequence were detected in the swine sequence and the sequence of the protein binding site of T early alpha, the sequence of the alpha enhancer element and the conserved sequence block between TRAJ3 and TRAJ4 are highly conserved. Insertion of the repetitive sequences that interspersed after the differentiation of the species in mammals such as short interspersed nucleotide elements is markedly suppressed in comparison to other genomic regions, while the composition of the mammalian-wide interspersed sequences is relatively conserved in human and swine. This observation indicates the existence of a highly selective pressure to conserve this genomic region around TRAJ throughout the evolution of mammals.     

An improved method for the detection of HIV antigen in the blood of carriers

The measurement of HIV antigen levels in sera or plasma of HIV-infected individuals is critical for determining the existence of antigen or infectious virus before seroconversion and for prognosis. Pretreatment of sera or plasma of HIV carriers by heating at 70 degrees C for 10 min at an acidic pH enabled us to estimate antigens efficiently in immune complexes. This procedure will also be useful in determining antigen levels in HIV carriers more precisely.     

Peroxyl radical scavenging capability of fish sauces measured by the chemiluminescence method

Oxygen-related free radicals have been suggested as a cause of aging and various diseases, for example, various cancers and rheumatoid arthritis. A radical scavenger as an antioxidant has been sought in foods. Fish sauces are traditional Asian fermented seasonings. Using the luminol chemiluminescence method, the peroxyl radical scavenging capability of fish sauces was examined. From the IC50 values, many fish sauces have been shown to have a strong scavenging capability as well as soy sauces. A scavenging mechanism is also proposed.     

Characterization of host-range and temperature-sensitive mutants of adenovirus type 5 with particular regard to transformation of a hamster embryo cell line (Nil)

Seventeen conditional lethal mutants (7 host-range and 10 temperature-sensitive) of adenovirus type 5 (Ad5) were classified by complementation test and characterized physiologically in viral-DNA synthesis, induction of cell DNA synthesis (in hamster kidney cells), capsid polypeptides production, and transformation of Nil cells (a hamster embryo cell line) under the restrictive conditions.Seven host-range (hr) mutants were divided into six groups by complementation test and into three classes by phenotypic characterization. Mutants assigned to class III (complementation groups D, E, F) were positive in viral-DNA synthesis and capsid polypeptides (hexon, penton base, fiber) production, and showed some degree of leakiness. Class II mutants (complementation groups B, C) were positive in viral-DNA synthesis with a small amount of capsid polypeptides production. Class I mutant (complementation group A) was an early mutant defective in viral-DNA synthesis but positive in induction of host-DNA synthesis. Transformation of Nil cells was observed with classes I and II mutants and not with class III mutants.Ten temperature-sensitive (ts) mutants were divided into seven complementation groups and into five classes by the available phenotypic criteria. Class V mutant (complementation group G) was positive in viral-DNA synthesis and capsid polypeptides production with extreme leakiness. Class IV mutants (complementation groups E, F) were positive in viral-DNA synthesis and capsid polypeptides production. Class III mutants (complementation groups C, D) were quite similar to class IV except for reduced hexon production. Class II mutants (complementation group B) were early mutants defective in viral-DNA synthesis but positive in induction of host-DNA synthesis. Class I mutants (complementation group A) were similar to class II but with a reduced degree of induction of host-DNA synthesis. Transformation of Nil cells was observed with classes II, III, and IV mutants and not with I and V mutants.In brief, the phenotypic characterization of hr and ts mutants in infection of hamster cells showed a good correlation between complementation grouping and the defective function. Transformation of Nil cells was observed with most groups of the mutants except for the apparently leaky late groups and one group of early mutants under the restrictive conditions.     

Retinoblastoma protein prevents staurosporine-induced cell death in a retinoblastoma-defective human glioma cell line.

OBJECTIVE: To investigate the mechanism of staurosporine-induced glioma cell death and cell cycle arrest using adenovirus-mediated gene transfection, as well as the function of retinoblastoma (Rb) and genetic instability induced by staurosporine. METHODS: Cell cycle regulation, cell death and nuclear abnormalities induced by staurosporine were examined using an adenovirus vector expressing Rb, p16 or p21 genes in human glioma cell lines. RESULTS: The Rb-defective SF-539 cell line was resistant to staurosporine compared with cell lines expressing intact Rb. SF-539 glioma cells exposed to staurosporine became multinucleated and then died. Multinucleation was prevented in SF-539 cells transfected with the Rb gene, thus decreasing the death rate of these cells. CONCLUSIONS: These results imply that enforced Rb expression protects cells from genomic instability induced by staurosporine regardless of its upstream molecular effects.