Primary gastric T-cell lymphoma not associated with human T-lymphotropic virus type I: a case report and review of the literature.

Primary gastric T-cell lymphoma (PGTL) not associated with human T-lymphotropic virus type I (HTLV-I) is extremely rare and such a case is reported herein. The patient was a 58-year-old Japanese male presenting with submucosal tumor of the stomach identified on endoscopic examination. The lesion was diagnosed as non-Hodgkin's lymphoma by endoscopic biopsy and classified as peripheral T-cell lymphoma, unspecified, due to clonal rearrangement of the T-cell receptor beta (TCR) gene and expression of TCR beta protein in the absence of B-cell genotypes and phenotypes. Unlike previously reported cases of HTLV-I-unassociated PGTL, lymphoma in the current case was characterized histologically as "low grade" and phenotypically as CD4+, TIA-1+, granzyme B+, and CD103-. The lymphoma responded well to chemotherapy and radiation, and the patient was well with no detectable disease 10 months after initiation of therapy. A review of patients with PGTL in the literature revealed a few long-term survivors, and the investigation of therapeutic strategies for PGTL is, therefore, necessary.

Molecular cloning and sequencing of myosin light chains in human megakaryoblastic leukemia cells.

Myosin light chain genes of hematopoietic cells have yet to be characterized. We cloned the full-length cDNAs of 20 kDa regulatory myosin light chain (MLC-2) and 17 kDa essential myosin light chain (MLC-3) from Meg-01, a human megakaryoblastic leukemia cell line. Both MLC-2 and MLC-3 gene are transcribed ubiquitously in various hematopoietic cells. The MLC-2 open reading frame of 516 nucleotides encoding a protein of 172 residues was detected in cloned cDNA of 967 nucleotides. The Ca2+-binding domain and five phosphorylation sites were highly conserved. The deduced amino acid sequence has a 99.4% and 100% homology with that of human fetus brain and human lymphocyte, respectively. The MLC-3 open reading frame of 453 nucleotides encoding a protein of 151 residues was detected in cloned cDNA of 742 nucleotide. The MLC-3 protein is 99.3% identical to that of human fibroblasts. These results suggest that hematopoietic myosin light chain proteins are similar to those of other nonmuscle cells and smooth muscle, thus differing from skeletal and cardiac muscles.

In vitro stability of biphasic calcium phosphate ceramics.

Biphasic calcium phosphate ceramics consist of both beta-tricalcium phosphate and hydroxyapatite. This study was performed to examine the in vitro stability of biphasic calcium phosphate ceramics in deionized distilled water and in physiological solutions. Biphasic calcium phosphates of two different molar ratios and pure hydroxyapatite and pure beta-tricalcium phosphate granules were tested. X-ray diffraction data were obtained before and after immersion. Surface morphology was compared using scanning electron microscopy. The pure beta-tricalcium phosphate and the beta-tricalcium phosphate in the biphasic calcium phosphate ceramics gradually converted to apatite. Needle-like apatite crystals were observed on the surface of biphasic calcium phosphate and beta-tricalcium phosphate, but hydroxyapatite showed no change.

Comparative study of hydroxyapatite and titanium dental implants in dogs.

This study compares the clinical performances and histologic response in dogs to a cylindrical implant with a surface consisting of dense hydroxyapatite (HA) and a threaded titanium implant in functionally loaded and unloaded conditions. Implantation was performed in five dogs, which were killed at 2 or 4 months postfunctional condition (4 or 6 months after implantation). Clinical evaluation showed that neither implant demonstrated significant movement, and assessment of gingival inflammation and sulcus depth showed no significant differences between them. After axial sectioning, the titanium implants were easily removed from the bone, whereas the HA-coated implants were adherent to the bone. Histologically, both implants showed osteogenic ingrowth to the surface in functional and nonfunctional conditions. High-magnification scanning electron micrographs of plastic sections showed that a portion of the interface between the HA-coated implant and the bone showed no gap, whereas gaps were observed at all interfaces with the titanium implant. Histomorphometric analysis by light microscopy indicated that there was no significant difference in the percent bone contact length. Clinically, the two implants behaved similarly.

T-kinin is released from T-kininogen by consecutive cleavage by cathepsin E-like proteinase and 72 kDa proteinase.

Using highly purified T-kininogen and cathepsin E-like proteinase and 72 kDa proteinase in rat spleen, the release of T-kinin from T-kininogen was found to occur by consecutive cleavage by cathepsin E-like proteinase and 72 kDa proteinase. 72 kDa proteinase seems to be serine proteinase, because it was completely inhibited by diisopropyl fluorophosphate but not by pepstatin, leupeptin and bestatin.

Glandular kallikrein, renin and tonin in tissues of diabetic and hypertensive rats.

The submaxillary gland and kidney of diabetic and hypertensive rats were compared for their content of glandular kallikrein and the activities of tonin and renin. The submaxillary glands and the kidneys of both diabetic Wistar strain and hypertensive rats contained significantly less glandular kallikrein than non-diabetic Wistar strain and hypertensive rats (reduction fron 40 to 76%). The renin activity of the kidney showed only a slight change in spite of diabetes, whereas the activity of the submaxillary gland decreased in parallel with the reduction of the kallikrein content when diabetes was induced. On the other hand, the tonin of the submaxillary gland, which has a potent hypertensive activity like renin, was not affected by induction of diabetes. However, the tonin activity in hypertensive rats was significantly higher (p less than 0.001) than that in the normotensive rats (His-Leu, 168.7 +/- 10.1 vs. 131.5 +/- 17.3 nmol/min X mg protein).