Expression of the c-kit protein in human solid tumors and in corresponding fetal and adult normal tissues

The proto-oncogene c-kit encodes a transmembrane tyrosine kinase receptor that is thought to play an important role in hematopoiesis, spermatogenesis, and melanogenesis. We previously showed that the c-kit messenger RNA is preferentially expressed in small cell lung cancer and that its ligand, stem cell factor, is expressed in a broad spectrum of human cancers. Using anti-c-kit antisera raised against synthetic peptides, in situ localization of the c-kit protein in various human solid tumors as well as in corresponding fetal and adult normal tissues was studied by the ABC method. The results suggest that the c-kit gene products may be involved in the pathogenesis of a very restricted subset of human solid tumors such as small cell lung cancer. Interestingly, nuclear protein immunologically related to c-kit was found in both normal and neoplastic medullary cells of the adrenal gland.

Treatment of myasthenia gravis: a comparison of the natural course and current therapies

Ninety-five patients with generalized myasthenia gravis were followed for 10 years to evaluate the long term effects of prednisolone, thymectomy, or both, and they were compared with a group only with anticholinesterase treatment. Only 15.0% of the patients with anticholinesterase alone had showed improvement 10 years after the onset, but more than 60% of those treated with prednisolone, thymectomy, or both showed improvement. Especially thymectomy induced complete remissions at 10 years after surgery in more than 20% of the patients. There was no difference between the histology of the thymi and clinical severity, or anti-acetylcholine receptor (AChR) antibody titer. In patients who showed improvement classified "good" of higher 10 years after thymectomy with or without prednisolone, anti-AChR antibody titers swiftly decreased to 37.8% of the value before surgery, and remained low thereafter. This result suggests that the marked decrease in anti-AChR antibody titers within 1 month after thymectomy is a favorable prognostic sign in myasthenia gravis patients who have undergone thymectomy.

Isolation of a novel cDNA clone showing marked similarity to ME491/CD63 superfamily

A novel cDNA clone, A15, was isolated by the differential screening of a cDNA library of an immature T cell line, HPB-ALL using radioactive cDNA probes from the mRNA of either HPB-ALL or peripheral blood lymphocytes. It hybridized to a single mRNA species of about 2.0 kilobases which is expressed in HPB-ALL cell line, but not in the PBL or a promyelocytic leukemia cell line, HL-60. The A15 gene codes for a protein of 244 amino acids which contains four potential transmembrane domains and four possible N-linked glycosylation sites. A computer-aided comparison showed a marked similarity to several other membrane proteins: CD9, CD37, CD53, TAPA-1, Sm23, CO-029, and ME491/CD63.

Phenotypic and genotypic characterization of 14 leukemia and lymphoma cell lines with 11q23 translocations

11q23 translocation is the most popular chromosomal abnormality in infant leukemia. In adults, it is often encountered in non-Hodgkin's lymphoma (NHL). In this study, we analyzed the phenotypic and genotypic characteristics of 9 acute leukemic cell lines with 11q23 translocations and one with deletion of the 11q23 locus, nine of which were established by researchers in this group, together with 4 NHL cell lines with 11q23 translocations. All lines were considered to belong to the B-cell lineage at different stages. All 10 leukemic lines showed clonal rearrangement of the immunoglobulin heavy chain (IgH) gene: two corresponded to the B-precursor stage (CD19+, cytoplasmic mu-), while the other 8 corresponded to the pre-B stage (cytoplasmic mu+). All 4 NHL lines showed rearrangements of both the IgH and Ig kappa genes with three expressing surface Ig; specifically, mature B-cell phenotype. As for myelocytic-monocytic markers, at least one out of 4 antigens examined were positive in 8 of the 10 leukemic cell lines, while only one of the 4 NHL lines was reactive. There were essentially no clear phenotypic or genotypic differences between t(4;11) and t(11;19) cell lines, supporting the view that both diseases have similar clinicopathological characteristics. These cell lines are also valuable for cloning genes at the chromosomal breakpoints.

The RCK gene associated with t(11;14) translocation is distinct from the MLL/ALL-1 gene with t(4;11) and t(11;19) translocations

We previously demonstrated that the 11q23 breakpoint region, designated the RCK locus, of the RC-K8 B-lymphoma cell line with t(11;14)(q23;q32) is centromeric to PBGD, while breakpoints of infantile leukemia cell lines with t(11;19)(q23;p13) are detectable by pulsed-field gel electrophoresis with the CD3D probe. In the present study, using a probe within 1.0 kilobase of the t(11;14) breakpoint, we isolated a partial complementary DNA clone for the putative RCK gene, which detects a 7.5-kilobase mRNA. Sequence analysis predicted a novel protein of 472 amino acids which demonstrated sequence homology to a translation initiation factor/helicase family. We also isolated a phage clone from the CD3D/G yeast artificial chromosome clone (yB22B2) which detects 11- and 12-kilobase mRNAs, most likely for the MLL/ALL-1 gene associated t(4;11)(q21;q23) and t(11;19)(q23;p13) translocations. By pulsed-field gel electrophoresis after NotI digestion, this recombinant clone is on a 96-kilobase fragment, while RCK and PBGD probes are on a more telomeric 690-kilobase NotI fragment. These results, altogether, suggested that two different genes, RCK and MLL/ALL-1, are associated with 11q23 translocation of hematopoietic tumors.

The establishment of an interleukin-6-dependent myeloma cell line (FLAM-76) carrying t(11;14)(q13;q32) chromosome abnormality from an aggressive nonsecretory plasma cell leukemia

A new myeloma cell line designated FLAM-76 was established from a patient with an aggressive nonsecretory plasma cell leukemia. The cell line exhibited morphologic features of flaming cells and contained an abundant eosinophilic cytoplasm with many dilated cisternae of rough endoplasmic reticulum. FLAM-76 cells were positive for cytoplasmic kappa (kapp)-type immunoglobulin but did not secrete it into the culture medium. The cells proliferated in the presence of exogenous interleukin-6 (IL-6) and more than 800 pg/ml of IL-6 was necessary for their continuous growth. The cells did not grow without IL-6, and they did not produce IL-6. Thus, the growth of FLAM-76 appeared to be regulated by the paracrine mechanism of IL-6. Alpha-interferon (alpha-IFN) inhibited the IL-6-dependent growth of FLAM-76 in doses greater than 1000 U/ml. FLAM-76 cells expressed CD38 (OKT10) and cell adhesion-associated antigens such as CD44 and CD54 (ICAM-1). Chromosome analysis revealed FLAM-76 to have a hypodiploid chromosome constitution with t(11;14)(q13;q32) abnormality, which frequently is seen in neoplasms of B-cell origin. Immunoglobulin (JH and Ck) gene rearrangement (but no BCL-1 gene rearrangement) was found in this cell line.

Histogenesis of diffuse small cleaved cell lymphoma. An immunohistochemical and molecular genetic (bcl-2 gene) study with comparison to follicular small cleaved cell lymphoma and mantle zone lymphoma

Immunohistochemical and molecular genetic (bcl-2 gene) studies were performed on specimens from 24 patients with follicular small cleaved cell lymphoma (FSCCL), 24 patients with diffuse small cleaved cell lymphoma (DSCCL) and 4 patients with mantle zone lymphoma (MZL) to determine the cellular origin of the disease and whether or not DSCCL represents the diffuse counterpart of FSCCL. Two patients with FSCCL, 22 patients with DSCCL, and all of the patients with MZL had a phenotype of mantle zone (MZ) B-lymphocytes (SIgD+, Leu-1+, Leu-8+, positive alkaline phosphatase [ALPase+], and negative common acute lymphoblastic leukemia antigen [CALLA-]), and all the tested patients (2 patients with FSCCL, 13 patients with DSCCL, and 4 patients with MZL) had germlines of bcl-2 gene. Fourteen patients with FSCCL and 1 patient with DSCCL had a phenotype of follicular center cells (FCC) (CALLA+, SIgD-, Leu-1-, Leu-8- and negative ALPase), and 11 patients with FSCCL had bcl-2 gene rearrangements. These results indicate that FSCCL are almost always derived from FCC, whereas some FSCCL, most DSCCL, and all MZL are derived from MZ B-lymphocytes, and these lymphomas should be included in the same category as MZ B-lymphocyte-derived lymphomas. Histologically diagnosed DSCCL often may represent a diffuse counterpart of MZ B-lymphocyte-derived lymphoma. MZ B-lymphocyte-derived lymphomas histologically show a follicular (nodular), a follicular MZ, or a diffuse growth pattern and clinically show a high incidence of peripheral blood (PB) involvement or bone marrow (BM) involvement.

Gene rearrangement and overexpression of PRAD1 in lymphoid malignancy with t(11;14)(q13;q32) translocation

The proto-oncogene PRAD1 (parathyroid adenoma 1) on chromosome 11q13 was found to be overexpressed in all five B-cell lines with t(11;14)(q13;q32) translocation tested. One B-cell lymphoma and four myeloma cell lines with this translocation demonstrated more than 10-fold overexpression as determined by Northern blot analysis, when compared with normal lymphoid tissues such as thymus, spleen and lymph node. Hematopoietic cell lines without the translocation were also examined, but none of these demonstrated the overexpression, confirming that overexpression of the PRAD1 gene is associated with t(11;14) translocation. A truncated form of mRNA was seen in one of five cell lines with the translocation, SP-49. Hybridization with different regions of the PRAD1 cDNA revealed that the truncated form of mRNA retained the coding region but had lost the 3' untranslated region. Southern blot analysis demonstrated a gene rearrangement in this SP-49 cell line. To study the genetic alteration responsible for the truncated form of mRNA in this cell line, the rearranged allele as well as the germline allele were cloned. The restriction map revealed that the rearranged portion was at the 3' end of the PRAD1 gene, eliminating the mRNA-destabilizing signal AUUUA. Human-rodent hybrid cell analysis demonstrated that the region introduced 3' of PRAD1 was derived from chromosome 11, suggesting that the PRAD1 gene region is deleted at the 3' end. Over-expression of the PRAD1 gene in association with t(11;14)(q13;q32) translocation suggested that in these cases the regulation of PRAD1 was altered by the juxtaposed gene, most likely the immunoglobulin heavy-chain gene from chromosome 14.

CD7 expression in malignant pleural mesothelioma

CD7 antigen was found to be expressed on malignant mesothelioma arising from the right pleura in a 15-year-old girl not only by immunostaining using monoclonal antibodies, but also by Northern blot analysis. The level of expression in this tumor was comparable to those in T-cell lines, Jurkat and CCRF-CEM. Cytogenetic analysis of the tumor showed hypodiploidy (n = 43). CD7 has been regarded as one of the hematopoietic cell markers selectively expressed on the majority of T cells and multipotential stem cells. To our knowledge, this is the first report of a non-hematopoietic tumor expressing CD7.

[Overexpression of PRAD1 gene in B-cell malignancy with t(11;14)(q13;q32) translocation]

PRAD1 (parathyroid adenoma 1) gene at chromosome 11q13 has been cloned from parathyroid adenomas as a putative oncogene, activated by translocation with the parathyroid hormone gene. 4.5 kb and 1.7 kb mRNA are transcribed and both have the same open reading frame of 885 bp encoding 34 kd protein of a cyclin gene family, cyclin D1. Recently, overexpression of PRAD1 gene has been reported to be correlated closely with the rearrangement of bcl-1 locus, particularly in centrocytic lymphoma. In our study, overexpression of PRAD1 gene was shown in five B cell lines with t(11;14)(q13;q32) including one centrocytic lymphoma line and 4 myeloma lines, when compared with other hematopoietic cell lines without translocation. One of the cell lines, SP-49, demonstrated a truncated mRNA of 3.4 kb, in addition to 1.7 kb of normal size. Southern blot analysis demonstrated a rearrangement with PRAD1 cDNA probe, suggesting that the gene is altered in this particular cell line. By cloning analysis, we confirmed that 1.8 kb deletion in 3' region of PRAD1 gene eliminating the destabilizing signal of PRAD1 mRNA, gave rise to the aberrant mRNA of 3.4 kb. These findings suggest that PRAD1 gene is most likely the candidate oncogene for bcl-1 activated by t(11; 14)(q13;q32) translocation. The gene alteration found in one cell line, SP-49, might also play an important role for deregulation of the gene.

Phenotypic and genotypic lineage switch of a lymphoma with shared chromosome translocation and T-cell receptor gamma gene rearrangement

A case of non-Hodgkin's lymphoma showed a phenotypic and genotypic cell lineage switch twice during nine years of his clinical history; first, T-cell type, pleomorphic small cell lymphoma developed, followed by B-cell type, diffuse centroblastic/centrocytic lymphoma, and finally T-zone lymphoma without follicles again developed, from which AST-1 cultured cell line was established. Karyotype analysis demonstrated a shared abnormal chromosome, der(1)t(1;?)(p36;?), among the first relapsed B-cell tumor, the second relapsed T-cell tumor and AST-1 cell line. Furthermore, T-cell receptor (TCR) gamma gene rearrangement bands of the same size were observed in the first relapsed B-cell tumor and the second relapsed T-cell tumor as well as AST-1 cell line. These results suggested that both relapsed tumors of different cell lineages are derived from a common malignant clone, presumably a committed lymphoid stem cell. A unique translocation, t(2;14)(q37;q11.2), which may involve TCR delta/alpha gene complex, was observed in the second relapsed tumor and AST-1 cells. To attempt to isolate the breakpoint of this translocation, the configuration of TCR delta/alpha gene complex was studied. The result showed that two rearrangements of TCR alpha gene detected with J alpha probes were the products of the normal TCR rearrangement process, and were not involved in the translocation at this region. This patient, together with the AST-1 cell line, provided us a unique opportunity to study the development and clonal evolution of malignant lymphoma.

An outbreak of Legionnaires' pneumonia in a nursing home

An outbreak of Legionnaires' pneumonia occurred at a nursing home in December 1990. A 79-year-old female and a 73-year-old male clerk who were staying at the nursing home developed pneumonia with only a 5-day interval. Legionella pneumophila serogroup I was isolated from transtracheal aspirate of the former and sputum of the latter. After treatment with a combination of erythromycin and rifampicin both patients improved. Serological surveillance of inpatients and staff of the nursing home was performed in February 1991. Seven out of 51 samples (14.0%) showed a titer higher than 1:128 of anti-Legionella pneumophila serogroup I antibody determined by indirect immunofluorescence; two of these seven complained of respiratory symptoms. Molecular epidemiology analyzed by restriction endonuclease digestion of isolated L. pneumophila showed an identical pattern which suggested a common origin.

Rearrangements on chromosome 11q23 in hematopoietic tumor-associated t(11;14) and t(11;19) translocations

We previously demonstrated that the breakpoint of t(11;14)(q23;q32) in the RC-K8 B cell lymphoma cell line lies between CD3 and THY1/ETS1 on chromosome 11q23, and we cloned this region and named it the rck locus. Pulsed-field gel electrophoresis showed that the rck probe B (distal to the breakpoint) and the porphobilinogen deaminase (PBGD) probe detect the same germ line band and also the same rearranged band when DNA from RC-K8 cells was digested with NotI enzyme. Furthermore, Southern blot analysis with somatic cell hybrids showed that the PBGD gene moved to the 14q+chromosome, which confirmed PBGD to be more distal to the centromere than the rck locus. These data allowed us to construct the following order of genes: 11 cen-q23-CD3-rck-PBGD-THY1/ETS1. In this study, three infantile leukemia cell lines with t(11;19)(q23;p13) translocation were also analyzed by pulsed-field gel electrophoresis. CD3D probe detected the rearranged bands in DNA from two of them after digestion with NotI and SacII enzymes, demonstrating that the breakpoints of both cell lines were estimated to be within 360 kilobases of CD3D.

[A case of aortitis syndrome complicated with amyloidosis, type AA]

We recently saw a patient who had aortitis syndrome associated with secondary amyloidosis. To our knowledge, she is the fourth report of this complication occurring in aortitis syndrome. In November 1985, the patient, a 18 year-old woman, was admitted to our hospital because of a high fever, back pain, abdominal pain and general fatigue. On physical examination, bruit was audible on the abdomen, bilateral radial artery was weakly palpable. Angiography showed the stenosis of bilateral carotid artery, subclavian artery, renal artery and superior mesenteric artery. From the above findings, she was diagnosed aortitis syndrome, and treatment was begun with prednisolone. However, she developed recurrently a high fever, chest pain, abdominal pain and exertional dyspnea. Laboratory findings at the active stage revealed the marked elevation of leukocytes, erythrocyte sedimentation rate and C-reactive protein. On her clinical course, the number of circulating thrombocytes was paralleled with the activity of the disease. On June 1988, she developed suddenly a high fever and severe pain of abdomen. Pathological findings of her stomach showed the deposition of amyloid protein A. Laboratory findings depicted the marked increment of thrombocytes, beta-thromboglobulin and platelet factor 4. These results suggest that circulating thrombocytes may play a role in product ion of amyloid protein.

Staurosporine, a protein kinase inhibitor, attenuates intracellular Ca(2+)-dependent contractions of strips of rabbit aorta

The protein kinase inhibitor staurosporine was found to be a potent relaxant of rabbit aortic strips contracted by various agonists. This relaxing effect was slow, long-lasting and in a non-competitive fashion against various agonists. The effect of staurosporine on the KCl-induced contraction was not altered by atropine, propranolol, theophylline or indomethacin. Staurosporine (5-200 nM) inhibited the contractile responses to prostaglandin F2 alpha (3 microM), endothelin (0.1 microM), phenylephrine (3 microM) and KCl (30 mM), with ED50 values of 10.8 +/- 0.6, 24.6 +/- 8.7, 48.8 +/- 7.0, 54.0 +/- 12.7 nM, respectively. Even in Ca(2+)-free physiological salt solution, staurosporine potently antagonized the contractile responses elicited by 10 microM prostaglandin F2 alpha and 0.1 microM endothelin; in fact it was more effective than it was in normal Ca2+ solution: ED50 of 11.3 +/- 3.8 vs. 21.0 +/- 4.4 nM (P less than 0.02), and of 10.6 +/- 3.6 vs. 24.6 +/- 4.3 nM (P less than 0.01), respectively. Thus, staurosporine has an equipotent inhibitory action on intracellular and extracellular calcium-dependent contractions of aortic tissues.

[bcl-2 gene in B cell lymphoma]

In t(14;18) lymphomas, bcl-2 gene is activated by the juxtaposition of immunoglobulin (Ig) gene. The fused bcl-2-Ig gene generates chimeric mRNAs which consist of bcl-2 at 5' side and Ig at 3' side. Chimeric mRNA does not disrupt the bcl-2 coding frame of 239 amino acid polypeptide. Activated bcl-2 gene introduced in normal B lymphoblastoid cells (LCL) demonstrated an increased cloning efficiency in soft agar but failed to confer tumorigenicity to LCLs as a single agent. bcl-2 gene rearrangement in Japaneses B cell lymphoma was studied and found that 10 out of 32 cases of follicular lymphoma (31%) and 5 out of 56 cases of diffuse lymphoma (9%) were rearranged, suggesting less frequency of B cell lymphoma, particularly follicular lymphoma in Japan is partly due to less bcl-2 involvement than American cases. Three cases out of 15 cases with bcl-2 rearrangement demonstrated a unique pattern of rearrangement. Two cases of the three were analysed and found that both cases were translocated at the later step than DH-JH joining of Ig rearrangement. Thus, bcl-2 translocation in Japanese B cell lymphomas might occur at the later stage of B cell development, when compared with that in American cases. Less involvement of bcl-2 in Japanese B cell lymphoma may be explained by low susceptibility to bcl-2 rearrangement at the step of DH-JH recombination.

[BCL-2 gene in lymphocytic malignancy]

In t(14;18) (q32;q21) lymphomas, bcl-2 gene is activated by the juxtaposition of immunoglobulin (Ig) gene. The fused bcl-2-Ig gene generates chimeric mRNAs which consist of bcl-2 at 5' portion and Ig at 3' portion. Chimeric mRNA does not disrupt the bcl-2 coding frame of 239 amino acid polypeptide. Bcl-2-Ig transgenic mice demonstrated the extended B cell survival and the follicular lymphoproliferation, but they did not develop a malignancy until 25 weeks. Ten percent of them, however, developed malignant diffuse large-cell lymphomas after a long latency. Forty percent of these malignancies demonstrated the c-myc rearrangement, indicating that multiple step changes are required for malignant transformation in bcl-2 activated cells. Study on the bcl-2 gene rearrangement in Japanese B cell lymphoma and B-CLL revealed that 10 out of 32 cases of follicular lymphoma (31%), 5 out of 56 cases of diffuse lymphoma (9%) and 2 out of 30 cases of B-CLL (7%) were rearranged. Less frequency of B cell lymphoma, particularly follicular lymphoma in Japan might be partly due to the less bcl-2 involvement than in American cases. The ratio of bcl-2 involvement in B-CLL is not significantly different between Japan and U.S.A.. bcl-2 rearrangement at 5' promoter region is noted for Japanese B-CLL which was demonstrated for American cases. The clinical application of polymerase chain reaction for bcl-2 translocation was also discussed.

Molecular cloning of the gene coding for the human T cell differentiation antigen CD7

The CD7 molecule is a differentiation antigen found on the surface of T lymphocytes and also on a very minor fraction of acute nonlymphocytic leukemia (ANLL). To study the genomic structure of the CD7 gene, two clones (SY4 and SY22) were isolated by screening a genomic library with a CD7 cDNA probe. Restriction mapping of these two phage clones showed that both overlapped each other, covering a total length of 23 kilobases (kb). Transfection of mouse L cells demonstrated that SY22 contains the gene expressing the CD7 antigen reactive with monoclonal CD7 antibody (Tp40), while SY4 does not. Subcloning of a 10.5 kb fragment from a 14.4 kb insert of SY22 contained the structural gene for the CD7 antigen. Detailed restriction mapping and partial sequence analysis revealed the CD7 gene to consist of four exons. By RNase protection assay, multiple initiation sites -122 base pairs (bp) to -38 bp from ATG translation initiation site were demonstrated. The promoter region had high G + C content and contained two SP1 binding sites (CCGCCC) and an AP2 binding site (CCCCAGGC), but lacked CAAT and TATA motifs.

Effects of HA1077, a protein kinase inhibitor, on myosin phosphorylation and tension in smooth muscle

We examined the effects of HA1077, a potent inhibitor of protein kinases in vitro, on the relationship between tension and myosin-light chain (MLC20) phosphorylation in the initial phase of contraction of the rabbit aorta. The dose-response curve of HA1077 for MLC20 phosphorylation was to the left of the tension curve produced by 40 mM K+. In contrast, the potassium dose-response (15-100 mM) curves for tension and MLC20 phosphorylation were virtually identical. The nifedipine dose-response (1-3000 nM) curves for tension and MLC20 phosphorylation after 40 mM K(+)-stimulation were much the same. HA1077 inhibited the contraction induced by 30 microM prostaglandin F2 alpha (ED50 = 50 microM). Stimulation with prostaglandin F2 alpha induced both mono (MLC-P) and diphosphorylation (MLC-P2) of MLC20. In the presence of various concentrations of HA1077 (1-300 microM), the dose-response curves for MLC-P and MLC-P2 were also to the left of the tension curve. HA1077 inhibited MLC-P2 (ED50 less than microM) more effectively than it inhibited MLC-P (ED50 = 2.1 microM). These observations indicate that the relationship between tension and MLC20 phosphorylation involves inhibition of protein kinases by HA1077. The mechanism underlying the formation of MLC-P2 induced by prostaglandin F2 alpha may differ from that underlying MLC-P formation.

Molecular cloning of the chromosomal breakpoint of a B-cell lymphoma with the t(11;14)(q23;q32) translocation

The breakpoint of t(11;14)(q23;q32) chromosome translocation in a B-cell lymphoma line, RC-K8, was cloned. Immunoglobulin heavy chain (IGH) constant gene, C gamma 2 at the 5' end, was involved in this translocation, and the DNA segment juxtaposed to the C gamma 2 was proved to be derived from chromosome 11 by somatic cell hybrid study. The normal counterpart of chromosome 11 was also isolated. With a DNA probe near the breakpoint of chromosome 11, Southern blot analysis of RC-K8 and 10 other cases with translocation involving the 11q23 region was conducted, but no rearrangement bands have been observed thus far except for RC-K8.

[The relationship between the aortic pulse wave velocity and osteoporosis in elderly women]

The relationship between arteriosclerosis and osteoporosis (OP) was assessed in 20 elderly women. The aortic pulse wave velocity (PWV) was used as the index of arteriosclerosis and bone mineral content (BM) of the vertebral body, which was measured by quantitative computed tomography, was used as an index of OP. PWV and BM showed a significant correlation with aging (PWV and age: r = 0.466, p less than 0.05, BM and age: r = -0.487, p less than 0.05). In the group in which the serum alkaline phosphatase (ALP) was higher than 180 IU/l (n = 11), there was a significant inverse correlation between PWV and BM (r = -0.728, p less than 0.02). On the other hand, there was no correlation between PWV and BM in the group in which ALP was lower than 180 IU/l (n = 9). These results suggest that in cases with OP and high levels of ALP, calcium (Ca) seems to be released from the bone system and transferred to the wall of the aorta. The mechanism and pathogenesis of this Ca transference is unknown and should be investigated.

[Lung ventilation imaging with TECHNEGAS: clinical study of lung deposition and ventilation/perfusion]

In order to optimize inhalation method for lung ventilation imaging with Tc-99m-gas (TECHNEGAS), relation between lung deposition of TECHNEGAS and inhalation method was evaluated. Submaximal inhalation with breath-holding (BH), continuous submaximal inhalation (C) and tidal inhalation (TV) were compared in 35 patients (36 studies) with various lung diseases. Mean lung deposition of TECHNEGAS was 6.6-7.4%/LD in BH group and was significantly higher than other groups of inhalation method (p less than 0.05-0.001). Lung deposition increased according to the times of inhalation in C group. TV group resulted in the lowest lung deposition which was same as 5 times of inhalation in C group. Lung/filter ratio (L/F) was highest in BH group. Image quality of TECHNEGAS was significantly better in BH group. Hot spot in central airway was seen in 15% of patients. All of them was in TV or C groups. In order to improve lung deposition and image quality of the TECHNEGAS, sufficient breath-holding was important. L/F seemed to be the index of effective inhalation of the TECHNEGAS. TV was suitable for poorly cooperative or dyspneic patients. TECHNEGAS was useful for evaluation of lung ventilation to provide good quality image with safety and simplicity.

bcl-2 translocation in Japanese B cell lymphoma: novel bcl-2 translocation with immunoglobulin heavy chain diversity segment

Breakpoints of a lymphoma case with bcl-2 gene rearrangement that did not show comigration of immunoglobulin (Ig) heavy chain joining (JH) fragment were cloned. Sequence analysis revealed that the translocation broke the 3' side of the Ig heavy chain diversity (DH) segment at the heptamer recombination signal and each end was ligated to the bcl-2 locus. Since Southern blot demonstrated that both alleles of JH were rearranged, this translocation was suggested to have occurred at the step of VH-DH, or DH-DHJH recombination, one step later than that of DH-JH recombination where the common pattern of bcl-2 rearrangement generally occurs. Cases that showed comigration with JH fragment were also studied by polymerase chain reaction with 5' bcl-2 oligomer and 3' JH consensus anti-sense oligomer since it has been demonstrated that bcl-2 translocation at the major breakpoint clustering region (mbr) in American cases clusters within an about 150 bp region in the mbr. The results demonstrated that four out of five cases studied were amplified, indicating that the same clustering mechanism exists for Japanese cases. The present study, together with our previous report on Ig kappa-bcl-2, indicated that bcl-2 translocation in Japanese B cell lymphomas might occur at a later stage of B cell development, as compared with that in American cases. Less involvement of bcl-2 in Japanese B cell lymphoma may also be in part explainable by low susceptibility to bcl-2 rearrangement at the step of DH-JH recombination.

Diphosphorylation of myosin light chain in smooth muscle cells in culture. Possible involvement of protein kinase C

Prostaglandin (PG) F2 alpha (30 microM) stimulated both monophosphorylation and diphosphorylation of myosin light chain (MLC) in a smooth muscle cell line (SM-3). The diphosphorylation was significantly decreased by treatment with the protein kinase C inhibitor staurosporine (30 nM, 30 min) from 20.1% of total MLC to 4.5%. The protein kinase C down-regulation treatment of SM-3 cells with phorbol dibutyrate suppressed to 8.7% the MLC diphosphorylation activity in the SM-3 cells. This down-regulation treatment had little effect on the monophosphorylation. We propose that the MLC diphosphorylation in PGF2 alpha-stimulated SM-3 cells in culture may be regulated through mechanisms sensitive to protein kinase C.