Mutational analysis of superantigen activity responsible for the induction of skin erythema by streptococcal pyrogenic exotoxin C

Streptococcal pyrogenic exotoxin C (SPEC), when injected intradermally, induces erythema in unsensitized rabbits. In the present study, we examined whether this erythema induction is due to the T-cell stimulatory activity of SPEC as a superantigen. Analysis by using single-residue mutant SPECs indicated that mutant SPECs Y15I, A16E, and Y17I, in which tyrosine 15, alanine 16, and tyrosine 17 were replaced with isoleucine, glutamic acid, and isoleucine, respectively, exhibited significantly reduced mitogenic activity for Vbeta2(+) human T cells in vitro, and Y15I showed as much as a 1, 000-fold reduction. Y15I mutant SPEC, however, retained the ability to bind to major histocompatibility complex class II antigen and to form a homodimer, implying that residue 15 is critically important for the interaction of SPEC with T-cell antigen receptor beta chains. When injected intradermally into normal rabbits, wild-type SPEC induced a characteristic erythema after 3 h in a dose-dependent fashion, which was associated with polymorphonuclear and mononuclear cell infiltration. This erythema formation was found to be severely suppressed by systemic pretreatment with cyclosporin A, suggesting the involvement of host T cells. Y15I mutant SPEC exhibited nearly 1, 000-fold less erythema induction in vivo than wild-type SPEC. Altogether, the present results strongly suggest that erythema induction in rabbits by SPEC is attributable mostly to its T-cell stimulatory activity as a superantigen.

Immunological studies on PD-1 deficient mice: implication of PD-1 as a negative regulator for B cell responses

PD-1, an Ig superfamily member, contains an immunoreceptor tyrosine-based inhibitory motif in the cytoplasmic tail. It is expressed in a minor fraction of CD4-CD8- normal thymocytes and induced in peripheral lymphocytes following activation. To assess the possible roles of PD-1 in the immune responses, PD-1-deficient (PD-1-/-) mice were generated by a gene-targeting strategy. PD-1-4- mice developed and grew normally. Although the thymus was apparently normal, PD-1-/- mice showed moderate but consistent splenomegaly, which reflected the increased cellularity of both lymphoid and myeloid cells. The proliferative response of B cells by anti-IgM antibodies, but not of T cells by an anti-CD3 (145-2C11) mAb in vitro, was augmented in PD-1-/- mice as compared with control littermates. PD-1-/- mice showed increased serum levels of IgG2b, IgA and most strikingly IgG3, while those of IgM and IgG1 were comparable with control mice. Furthermore, PD-1-/- mice exhibited significantly augmented IgG3 anti-DNP antibody response to a type 2 T-independent antigen, DNP-Ficoll, with comparable IgM and IgG1 antibody responses with littermate controls. In the peritoneal cavity, the B-1 cell population in PD-1-/- mice exhibited significantly reduced expression of CD5, a negative regulator of B-1 cell activation, despite a marginal increase in the number of B-1 cells. Thus, PD-1 was suggested to be involved in the negative regulation for particular aspects of B cell proliferation and differentiation including class switching.

Iron-dependent oxidation, ubiquitination, and degradation of iron regulatory protein 2: implications for degradation of oxidized proteins

The ability of iron to catalyze formation of reactive oxygen species significantly contributes to its toxicity in cells and animals. Iron uptake and distribution is regulated tightly in mammalian cells, in part by iron regulatory protein 2 (IRP2), a protein that is degraded efficiently by the proteasome in iron-replete cells. Here, we demonstrate that IRP2 is oxidized and ubiquitinated in cells before degradation. Moreover, iron-dependent oxidation converts IRP2 into a substrate for ubiquitination in vitro. A regulatory pathway is described in which excess iron is sensed by its ability to catalyze site-specific oxidations in IRP2, oxidized IRP2 is ubiquitinated, and ubiquitinated IRP2 subsequently is degraded by the proteasome. Selective targeting and removal of oxidatively modified proteins may contribute to the turnover of many proteins that are degraded by the proteasome.

Human SPA-1 gene product selectively expressed in lymphoid tissues is a specific GTPase-activating protein for Rap1 and Rap2. Segregate expression profiles from a rap1GAP gene product

Mouse Spa-1 gene with a region homologous to the human rap1GAP gene is transcriptionally induced in the lymphocytes by mitogenic stimulation. Herein we have cloned a cDNA for its human counterpart. SPA-1 cDNA encodes a 130-kDa protein (p130(SPA-1)) consisting of proline-rich regions and rap1GAP-related domain followed by a coiled-coil stretch. Baculovirally expressed p130(SPA-1) exhibited GTPase-activating protein (GAP) activity for Rap1 and Rap2, but not for Ras, Rho, Cdc42, Rac, and Ran, with comparable specific activity to the rap1GAP gene product (p85/95(rap1GAP)). In the cells, p130(SPA-1) was mostly localized at the perinuclear membranous region co-localizing with Rap1 and Rap2. Expression of SPA-1 and rap1GAP genes tended to be segregate in various tissues, lymphoid tissues expressing abundant SPA-1 transcript without rap1GAP, while those such as brain, kidney, and pancreas exhibiting rap1GAP mRNA with little SPA-1. Promyelocytic HL-60 cells, which expressed p130(SPA-1) with little p85/95(rap1GAP) in uninduced state, showed progressive decline in p130(SPA-1) and conversely drastic increase in p85/95(rap1GAP) as they ceased from proliferation and differentiated into macrophages by 12-O-tetradecanoylphorbol-13-acetate. These results suggested that products of SPA-1 and rap1GAP genes, albeit comparable GAP activity for Rap1 and Rap2, functioned in the distinct contexts depending on cell types and/or states.

Involvement of NK1+ CD4- CD8- alphabeta T cells and endogenous IL-4 in non-MHC-restricted rejection of embryonal carcinoma in genetically resistant mice

Non-MHC-restricted rejection mechanisms against the murine MHC-negative F9 embryonal carcinoma cells were analyzed. Strains of C57BL/6 (B6) background were resistant to the tumors irrespective of H-2 haplotypes, while others, including BALB/c background, were susceptible. This resistance was suggested to be mediated primarily by the host thymus-dependent alphabeta T cells, since both athymic B6 nude and normal B6 mice depleted with alphabeta T cells showed susceptible phenotype. The difference of the nature of alphabeta T cells infiltrating in H-2-identical B6- and BALB.B-derived tumors was then comparatively analyzed. It was revealed that unique T cells with NK1+ CD4- CD8- (double negative (DN)) alphabeta TCR+ phenotype were accumulated significantly in B6, but few in BALB.B mice. The population freshly isolated from the F9 tumor tissues preferentially expressed potent IL-4 mRNA, and was suggested to be mostly responsible for the endogenous IL-4 production. Indeed, the injection of either anti-NK1.1 or anti-IL-4-neutralizing Ab into the normal B6 rendered them significantly susceptible to the tumor cells. These results strongly suggested that NK1+ DN alphabeta T cells were responsible primarily for the rejection mechanisms against F9 tumors. Histologically, F9 tumors in B6 mice were characterized by abundant macrophage infiltration and massive tumor necrosis, neither of which was observed in those in BALB.B nor B6 mice preinjected with anti-IL-4 Ab, indicating that both histologic features in the resistant strain were dependent on the endogenous IL-4. Present results provide one of the first instances in which a recently emerging minor T cell subpopulation, thymus-dependent NK1+ DN alphabeta T cells, plays an essential role in anti-tumor responses in vivo.

Involvement of NK1+ CD4- CD8- alphabeta T cells and endogenous IL-4 in non-MHC-restricted rejection of embryonal carcinoma in genetically resistant mice

Non-MHC-restricted rejection mechanisms against the murine MHC-negative F9 embryonal carcinoma cells were analyzed. Strains of C57BL/6 (B6) background were resistant to the tumors irrespective of H-2 haplotypes, while others, including BALB/c background, were susceptible. This resistance was suggested to be mediated primarily by the host thymus-dependent alphabeta T cells, since both athymic B6 nude and normal B6 mice depleted with alphabeta T cells showed susceptible phenotype. The difference of the nature of alphabeta T cells infiltrating in H-2-identical B6- and BALB.B-derived tumors was then comparatively analyzed. It was revealed that unique T cells with NK1+ CD4- CD8- (double negative (DN)) alphabeta TCR+ phenotype were accumulated significantly in B6, but few in BALB.B mice. The population freshly isolated from the F9 tumor tissues preferentially expressed potent IL-4 mRNA, and was suggested to be mostly responsible for the endogenous IL-4 production. Indeed, the injection of either anti-NK1.1 or anti-IL-4-neutralizing Ab into the normal B6 rendered them significantly susceptible to the tumor cells. These results strongly suggested that NK1+ DN alphabeta T cells were responsible primarily for the rejection mechanisms against F9 tumors. Histologically, F9 tumors in B6 mice were characterized by abundant macrophage infiltration and massive tumor necrosis, neither of which was observed in those in BALB.B nor B6 mice preinjected with anti-IL-4 Ab, indicating that both histologic features in the resistant strain were dependent on the endogenous IL-4. Present results provide one of the first instances in which a recently emerging minor T cell subpopulation, thymus-dependent NK1+ DN alphabeta T cells, plays an essential role in anti-tumor responses in vivo.

[A successful surgical case report of impending rupture of the true thoraco-abdominal aortic aneurysm induced by thrombosed-type acute aortic dissection (Stanford type A)]

Impending rupture of the true aneurysm of the thoraco-abdominal aorta induced by acute aortic dissection (Stanford type A) is very rare, and decision making of the therapeutic plain is difficult. A 88-year-old woman manifested severe back pain with hypotension. Chest computed tomographic examination revealed a true aneurysm of the thoraco-abdominal aorta and acute thrombosed-type aortic dissection (Stanford type A) with cardiac tamponade. Under the diagnosis of impending rupture of the thoraco-abdominal aortic aneurysm induced by acute aortic dissection (Stanford type A), graft replacement of the thoraco-abdominal aortic aneurysm and pericardial drainage were successfully performed. Two months later, computed tomographic examination revealed disappearance of the thrombosed false lumen in the ascending aorta.

Mitogen-inducible SIPA1 is mapped to the conserved syntenic groups of chromosome 19 in mouse and chromosome 11q13.3 centromeric to BCL1 in human

Sipa1, previously called Spa1, is transcriptionally induced in the murine lymphoid cells following mitogenic stimulation and encodes a protein with a domain related to Rap1 GTPase activating protein (Rap1GAP) at the N-terminus and to PEST sequences followed by a leucine zipper motif at the C-terminus. Herein mouse genomic Sipa1, which consisted of 16 exons, was cloned. Gene linkage analysis using (BXD) recombinant inbred strains indicated that Sipa1 was mapped to the most centromeric region of chromosome 19 syntenic with the long arm of human chromosome 11. Human SIPA1 cDNA exhibited a striking homology to that of mouse throughout the entire region, with the overall identity being 90% at the amino acid level. Human genomic clones, which hybridized with both mouse and human SIPA1 cDNA but not with RAP1GAP cDNA, were then isolated. Fluorescence in situ hybridization (FISH) analysis using the human genomic clones indicated that SIPA1 was indeed mapped to chromosome 11q13, most likely to the 11q13.3 subregion. It was further indicated by double-color FISH that SIPA1 was located in the centromeric neighborhood of CCND1/ PRAD1, a presumed BCL1 oncogene.

NK 1+ CD4- CD8- alphabeta T cells in the peritoneal cavity: specific T cell receptor-mediated cytotoxicity and selective IFN-gamma production against B cell leukemia and myeloma cells

NK1+ double negative (DN) alphabeta T cells were present in the peritoneal exudate cells (PEC) of both normal and athymic B6 mice, accounting for as much as 25% of the total T cells, while their numbers were far less in the PEC of BALB/c and (BALB/c x B6)F1 mice. IL-2-dependent clones established from the DN alphabeta T cell population in the PEC of IL-2 receptor alpha-chain transgenic B6 mice exhibited potent cytotoxicity against a series of B cell lineage leukemias and myelomas, such as CD5+BCL1 and MOPC, without affecting NK-susceptible targets. The cytotoxicity of the clones against BCL1 and MOPC was specifically inhibited by anti-CD3, anti-alphabetaTCR, or anti-relevant Vbeta (Vbeta8) Ab, but not by control Abs, indicating that it was mediated by the specific alphabetaTCR/CD3. Other BALB/c-derived target cells expressing both MHC class I and class II were not affected, and neither Ab against them affected the cytotoxicity, strongly suggesting that the cytotoxicity of NK1+ DN alphabeta T cell clones was independent of the particular MHC Ags. The clones produced IFN-gamma, but little IL-2 or IL-4, in response to anti-CD3 stimulation, to the susceptible, but not resistant, targets, and to IL-12. The clones exhibited TCRalpha (Valpha8) distinct from an invariant TCRalpha (Valpha14) reported to dominate in thymic NK1+ alphabeta T cells. The presence of DN alphabeta T cells with similar functional features in the normal PEC was confirmed by the short term stimulation in vitro. The present results along with other recent reports strongly suggested that, like the mainstream alphabeta T cells, the NK1+ DN alphabeta T cell population consisted of functionally heterogeneous subsets.

NK 1+ CD4- CD8- alphabeta T cells in the peritoneal cavity: specific T cell receptor-mediated cytotoxicity and selective IFN-gamma production against B cell leukemia and myeloma cells

NK1+ double negative (DN) alphabeta T cells were present in the peritoneal exudate cells (PEC) of both normal and athymic B6 mice, accounting for as much as 25% of the total T cells, while their numbers were far less in the PEC of BALB/c and (BALB/c x B6)F1 mice. IL-2-dependent clones established from the DN alphabeta T cell population in the PEC of IL-2 receptor alpha-chain transgenic B6 mice exhibited potent cytotoxicity against a series of B cell lineage leukemias and myelomas, such as CD5+BCL1 and MOPC, without affecting NK-susceptible targets. The cytotoxicity of the clones against BCL1 and MOPC was specifically inhibited by anti-CD3, anti-alphabetaTCR, or anti-relevant Vbeta (Vbeta8) Ab, but not by control Abs, indicating that it was mediated by the specific alphabetaTCR/CD3. Other BALB/c-derived target cells expressing both MHC class I and class II were not affected, and neither Ab against them affected the cytotoxicity, strongly suggesting that the cytotoxicity of NK1+ DN alphabeta T cell clones was independent of the particular MHC Ags. The clones produced IFN-gamma, but little IL-2 or IL-4, in response to anti-CD3 stimulation, to the susceptible, but not resistant, targets, and to IL-12. The clones exhibited TCRalpha (Valpha8) distinct from an invariant TCRalpha (Valpha14) reported to dominate in thymic NK1+ alphabeta T cells. The presence of DN alphabeta T cells with similar functional features in the normal PEC was confirmed by the short term stimulation in vitro. The present results along with other recent reports strongly suggested that, like the mainstream alphabeta T cells, the NK1+ DN alphabeta T cell population consisted of functionally heterogeneous subsets.

Surgical treatment for acute aortic arch dissection

Between March 1983 and December 1993, 24 consecutive patients with acute aortic dissection resulting from a tear located in the aortic arch or at the base of the innominate artery underwent surgical treatment. Before 1988, 11 patients (group 1) underwent either isolated ascending aorta replacement (eight cases) or composite graft replacement (three) by the conventional method. In this group, the hospital mortality rate was 36.4%; two of seven surviving patients required reoperation for aortic arch. After 1989, 13 patients (group 2) underwent either hemiarch replacement (five cases), total arch replacement (three), extended ascending aortic replacement or composite graft replacement with hemiarch replacement (one) under a brief period of circulatory arrest (mean 33.3 min) at a mean(range) rectal temperature of 20.8(18-23) degrees C by open distal anastomosis. The operative mortality rate in group 2 was 15.4%. Ten of 13 surviving patients are free from reoperation (mean follow-up 40 months). In most patients with acute type A dissection in which the tear is located at the proximal aortic arch or at the base of the innominate artery, the use of an open technique during a brief period of hypothermic circulatory arrest is advocated to: (1) perform a more secure distal anastomosis; (2) provide a more accurate assessment and resection of intimal disruption; and (3) avoid further aortic injury from the cross-clamp.

Developmentally regulated expression of the PD-1 protein on the surface of double-negative (CD4-CD8-) thymocytes

PD-1, a member of the Ig superfamily, was previously isolated from an apoptosis-induced T cell hybridoma 2B4.11 by subtractive hybridization. Expresson of the PD-1 mRNA is restricted to thymus in adult mice. Using an anti-PD-1 mAb (J43), we examined expression of the PD-1 protein during differentiation of thymocytes in normal adult, fetal and RAG-2(-/-) mice with or without anti-CD3 mAb stimulation. While PD-1 was expressed only on 3-5% of total normal thymocytes, approximately 34% of the CD4(-)CD8(-) double-negative (DN) fraction are PD-1(+) cells with two distinct expression levels (low and high). PD-1(high) thymocytes belonged to TCR gammadelta lineage cells. In the DN compartment of the TCR alphabeta lineage, PD-1 expression started at the low level from the CD44(+)CD25(+) stage and the majority of thymocytes expressed PD-1 at the CD44(-)CD25(-) stage in which the thymocytes express TCR beta chains. The anti-CD3epsilon antibody administration augmented the PD-1 expression as well as the differentiation of the CD44(-)CD25(+) DN cells into the CD44(-)CD25(-) DN stage, not only in normal mice but also in RAG-2-deficient mice. The fraction of the PD-1(low) cells in the CD4(+)CD8(+) double-positive (DP) compartment was very small (<5%) but increased by stimulation with the anti-CD3 antibody, although the total number of DP cells was drastically reduced. The results show that PD-1 expression is specifically induced at the stages preceding clonal selection.

[A case report of mitral valve plasty for traumatic mitral regurgitation]

A 64-year-old man was admitted to our hospital with a chief complaint of general fatigue on June 24, 1993. He had no history of rheumatic fever but bruised in the chest in September 1990. After that, his systolic murmur was noticed at the apex and echocardiogram showed the posterior chordal rupture of mitral valve. Mitral valve plasty was performed successfully.

[Regulatory mechanisms of lymphocyte proliferation: roles of Spa-1 gene]

Spa-1 genes is one of the secondary response genes specifically induced to express in the lymphoid cells following the mitogenic stimulations by antigens or mitogenic cytokines. Gene transfection experiments indicate that Spa-1 protein exhibits negative effect on cell growth and induces cell death when ectopically overexpressed. Spa-1 protein is a nuclear protein and suggested to function through the interaction with Ran, so far the only small G protein present in the nuclei, While Spa-1 mRNA is expressed in normal proliferating lymphocytes as well as factor-dependent cell lines, little mRNA is expressed in autonomously growing leukemic lines, suggesting the active repression of Spa-1 transcription in transformed cells. Analysis of this mechanism may provide a new insight into the transformation processes in lymphoid cells.

[A case of infective aortic valve endocarditis with splenic abscess]

A 47-year-old woman was admitted to our hospital with high fever, exertional dyspnea and left flank pain. Echocardiography revealed vegetations attached to the aortic valve and moderate aortic regurgitation. Streptococcus anginosus was identified by blood culture examination. Abdominal CT scan showed a low density area in the spleen. The diagnosis of infective aortic valve endocarditis with splenic abscess was obtained. The splenectomy and the aortic valve replacement were performed simultaneously after the treatment with antibiotics. The postoperative clinical course was uneventful. In the case of infective endocarditis with splenic abscess, the splenectomy concomitant with valve surgery should be performed for removing all of the infected tissues.

Decreases of CD4- and CD8-positive T lymphocytes in retired chromate workers

To investigate the effects of chromates on the human immune system, we measured total T lymphocytes and their two major subpopulations (CD4+ and CD8+ T lymphocytes) in the peripheral blood of 19 retired male workers who had been exposed to chromate at a chemical plant. The results indicated that both CD4+ and CD8+ T lymphocytes were significantly decreased, resulting in decreases in total T lymphocytes and total lymphocytes.

Perioperative coronary artery spasm in modified Bentall's operation for annulo-aortic ectasia in Marfan's syndrome. A case report of perioperative chordal rupture of the mitral valve

We experienced a rare case of Marfan's syndrome with annulo-aortic ectasia, aortic regurgitation and Prinzmetal's variant angina. In a modified Bentall's operation (button technique), perioperative severe coronary artery spasm occurred in spite of the preventive use of nitroglycerin infusion, which resulted in profound ventricular fibrillation and subsequent chordal rupture of the mitral valve with Sellers IV regurgitation. Use of nicardipine contained in cardioplegia, continuous infusion of nicardipine and nitroglycerin after aortic declamping completely prevented coronary spasm throughout the course of a second surgery for mitral valve replacement. It is worthy to report this case because of rarities such as Marfan's syndrome accompanied by Prinzmetal's variant angina, perioperative coronary artery spasm in modified Bentall's operation, and perioperative chordal rupture of the mitral valve and progression of mitral valve regurgitation. We also stress the efficacy of a new calcium antagonist, nicardipine, to prevent coronary artery spasm during open heart surgery.

[Horner syndrome due to mediastinal neurinoma--a case report]

Horner syndrome due to mediastinal neurinoma has been reported rare cases so far. We experienced a 55-year-old woman who developed Hornor syndrome due to mediastinal neurinoma and the patient received operation with no major complication. She was admitted to our hospital because of the left shoulder pain and the dilatation of the mediastinum on chest X-ray. She was found to have the left mild ptosis and CT scan showed left upper mediastinal tumor (12 cm in diameter) with tracheal compression. Aortography showed a 8.6 cm tumor stein and lower deviation of aortic arch. The feeding artery was branch of thyrocervical artery. Mediastinal neurinema was found by biopsy. During the operation, we found the origin was the left sympathetic nerve. The post operative course was uneventful however horner syndrome was progressed due to radical resection of the tumor.

Molecular cloning of a novel mitogen-inducible nuclear protein with a Ran GTPase-activating domain that affects cell cycle progression

We have cloned a novel cDNA (Spa-1) which is little expressed in the quiescent state but induced in the interleukin 2-stimulated cycling state of an interleukin 2-responsive murine lymphoid cell line by differential hybridization. Spa-1 mRNA (3.5 kb) was induced in normal lymphocytes following various types of mitogenic stimulation. In normal organs it is preferentially expressed in both fetal and adult lymphohematopoietic tissues. A Spa-1-encoded protein of 68 kDa is localized mostly in the nucleus. Its N-terminal domain is highly homologous to a human Rap1 GTPase-activating protein (GAP), and a fusion protein of this domain (SpanN) indeed exhibited GAP activity for Rap1/Rsr1 but not for Ras or Rho in vitro. Unlike the human Rap1 GAP, however, SpanN also exhibited GAP activity for Ran, so far the only known Ras-related GTPase in the nucleus. In the presence of serum, stable Spa-1 cDNA transfectants of NIH 3T3 cells (NIH/Spa-1) hardly overexpressed Spa-1 (p68), and they grew as normally as did the parental cells. When NIH/Spa-1 cells were serum starved to be arrested in the G1/G0 phase of the cell cycle, however, they, unlike the control cells, exhibited progressive Spa-1 p68 accumulation, and following the addition of serum they showed cell death resembling mitotic catastrophes of the S phase during cell cycle progression. The results indicate that the novel nuclear protein Spa-1, with a potentially active Ran GAP domain, severely hampers the mitogen-induced cell cycle progression when abnormally and/or prematurely expressed. Functions of the Spa-1 protein and its regulation are discussed in the context of its possible interaction with the Ran/RCC-1 system, which is involved in the coordinated nuclear functions, including cell division.

[Replacement of distal arch aneurysm: distal hemiarch replacement]

Among thoracic aortic aneurysm, operative result for distal arch aneurysm is poor. Approach auxiliary technique, and operative procedure are still controversial. We noticed that distal arch aneurysm frequently involve anterior lesser curvature of aortic arch, then we have designed "distal hemiarch replacement" that preserve branches of aortic arch and replace lesser curvature of arch sufficiently. Furthermore, we managed to prevent cerebral injury by atheromatous embolism using intraoperative echogram to detect atherosclerosis of aortic arch and the branches. Median approach, selective cerebral perfusion, and distal hemiarch replacement were performed consistently for seven distal arch aneurysm. As the result, all cases recovered without neurological deficit except one ruptured emergency case. Distal hemiarch replacement for distal arch aneurysm enabled sufficient essential removal and reconstruction of the thoracic aorta with minimal invasion. Intraoperative echogram could reduce operative cerebral injury and brought sufficient operative results.

[T cell development and selection in extrathymic environments]

Thymocytes express randomly diversified TCRs by TCR gene rearrangement and those reactive to self antigens are negatively selected while those capable of recognizing antigens in the context of self MHC antigens are positively selected. The selection process in the thymus for forming the TCR repertoire is a basic rule for the formation of T cell repertoire. Recently, however, certain T cells have been reported to be generated extra-thymically and exhibit the restricted TCR repertoire. Some of these T cells are suggested to recognize self antigens in a non-MHC-restricted fashion. Those self antigens, such as endogenous retrovirus, surface activation antigens, and bacterial antigens, are induced by exogenous stress, transformation and invading microorganisms. T cells which recognize such self antigens seem to be activated and expand clonally whenever the antigens are expressed in the periphery. Although the biological roles of the unique T cells remain obscure, it is suggested that they may participate in immune surveillance system to monitor cell integrity and to destroy cells altered by transformation and infection by microorganisms.

Pulmonary hypertension in systemic lupus erythematosus: a report of an autopsied case

An autopsied case of systemic lupus erythematosus with pulmonary hypertension is reported. A 29-year-old woman with a seven-year history of polyarthralgia, butterfly rash, nephrotic syndrome and Raynaud's phenomenon was admitted because of progressive dyspnea on exertion. Tests for antinuclear antibody, anti-cardiolipin antibody and lupus anticoagulant were positive. Echocardiographic examination revealed right ventricular hypertrophy and a moderate pericardial effusion. Estimated systolic pulmonary arterial pressure was 53 mmHg. Despite treatment with corticosteroids including pulse methylprednisolone therapy, lipo-PGE1 and warfarin, she died of progressive congestive heart failure. Postmortem examination of the pulmonary vasculature revealed findings consistent with plexogenic pulmonary arteriopathy, without evidence of vasculitis, fibrinoid necrosis, or thromboemboli.

Involvement of 4F2 antigen expressed on the MHC-negative target cells in the recognition of murine CD3+CD4-CD8- alpha beta (V alpha 4/V beta 2) T cells

T cells of an unique phenotype (CD3+CD4-CD8- alpha beta TCR+) develop in vitro from the hematopoietic progenitors, the majority of which carry homologous alpha beta TCR (V alpha 4J alpha 28/V beta 2D beta 1.1J beta 2.6). In the present study, antigen corresponding to the particular alpha beta TCR was investigated, taking advantage of the fact that growth of T cell hybridomas was arrested by their TCR stimulation. Results indicated that both syngeneic and allogeneic thymocytes, particularly from newborn mice, could specifically inhibit the proliferation of a T cell hybridoma with the V alpha 4/V beta 2 TCR (15H1.2). Proliferation of neither TCR-missing hybridoma subclones nor those with unrelated alpha beta TCRs was affected at all. It was also found that embryonal carcinoma (EC) cells without classical MHC antigens could specifically inhibit the proliferation of 15H1.2 cells. We then raised a mAb, 14.37, against an EC line, OTF9, that could interfere with the ability of them to inhibit the growth of 15H1.2. Pretreatment of 15H1.2 cells with anti-V beta 2 and OTF9 cells with 14.37 mAb respectively completely abrogated the growth inhibition of 15H1.2 by OTF9. The 14.37 antigen was a 120 kDa heterodimer glycoprotein consisting of 85 and 36 kDa proteins. In normal lymphoid tissues, the expression of 14.37 antigen exhibited an apparently inverse relationship with that of class I MHC antigens. Thus, ontogenically it was strongly expressed in fetal and newborn mice, rather rapidly declined thereafter, and remained at very low levels in adult organs. In a given stage, the distribution of 14.37 antigen and class I MHC was rather exclusive to each other.(ABSTRACT TRUNCATED AT 250 WORDS)

Isolated iliac artery aneurysm and its management

The records of 16 patients with 44 aneurysms of the iliac artery during a 12-year period (1981 to 1992) were retrospectively reviewed. The mean age was 71.2 (range 53-81) years; the male/female ratio was 7:1. An extremely high incidence of isolated iliac artery aneurysm was noted relative to abdominal aortic aneurysm (11.7%) during the same period. Aneurysms ranged in size from 2 to 12 cm. Rupture occurred in four patients (25%). Six patients presented urologic complications of ureteral stenosis, with hydronephrosis caused by perianeurysmal fibrosis in five. Thirteen patients underwent surgical treatment with emergency operation performed in four with rupture and one with impending rupture. The mortality rate for ruptured aneurysm was high (50%). The operative procedures for common iliac aneurysms were open resection in 18, aneurysmectomy in two, and thromboexclusion in three. For internal iliac aneurysms, the procedures were aneurysmorrhaphy (partial resection) in five, obliterative endoaneurysmorrhaphy in seven, aneurysmectomy in two, and thromboexclusion in two, with appropriate graft replacement. Endarterectomy and reimplantation of the inferior mesenteric artery, and internal iliac artery graft interposition were performed to prevent colon ischaemia in three and two patients, respectively. Ureterolysis was performed in three patients with ureteral stenosis caused by perianeurysmal fibrosis, which improved hydronephrosis and renal function in two. Early diagnosis and elective surgery before rupture is the treatment of choice for saving the patient's life. The importance of preventing colon ischaemia for bilateral internal iliac aneurysms and ureterolysis for ureter entrapped within perianeurysmal fibrosis is emphasized.

[Ventricular septal perforation following acute myocardial infarction in an 85-year-old woman]

An 85-year-old woman who experienced sudden severe chest and back pains was admitted to our hospital. On admission a pansystolic murmur was audible and the ECG showed an acute antero-septal myocardial infarction. Right heart catheterization revealed increased oxygen from the right atrium to the right ventricle, leading to the diagnosis of ventricular septal perforation (VSP). Hemodynamics of the patient were stabilized using only a low dosage of dopamine. However the heart weakened progressively, an operation was performed on the 13th day after the onset of the perforation. The post-operative course was uneventful. She is the oldest patient with VSP which has been successfully operated in Japan.

[A surgical treatment of ruptured arch aneurysm]

A 83-year-old woman was admitted to our hospital because of back pain and shock. Her chest X-ray and CT scan demonstrated a large arch aneurysm and hemothorax, suggesting ruptured aortic arch aneurysm. The ruptured aortic arch aneurysm was replaced with a woven Dacron graft under selective cerebral perfusion (SCP). Her postoperative course was uneventful without any neurological deficits. For the past three years, we have utilized SCP in 12 cases of arch aneurysms. There were three early deaths in this series. The cause of death were bleeding in one patient and cerebral accident in two patients. The latter two patients had severe atheromatous changes in the aortic wall. The SCP technique was a useful method of cerebral protection, especially for elderly patient with aortic arch aneurysm.

Adult Still's disease with Sjögren's syndrome successfully treated with intravenous pulse methylprednisolone and oral cyclophosphamide

A patient with adult Still's disease and Sjögren's syndrome failed to respond to conventional doses of corticosteroids. Therefore intravenous pulse methylprednisolone combined with oral cyclophosphamide was given which subsequently resolved the flare of rashes, fevers, and arthritis. This combination therapy may be a useful therapy to consider in patients with adult Still's disease who are resistant to conventional treatment and may allow a reduction in daily corticosteroid requirement.

[Giant cell arteritis and polymyalgia rheumatica presenting as subclavian artery obstruction]

Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are common diseases in the elderly. The arteritis usually affects medium sized vessels, but large vessel involvement can also occur leading to arm claudication, bruits, loss of pulses and pallor of the upper extremities. The differential diagnosis of large vessel arteritis includes atherosclerosis and Takayasu's disease. Atherosclerosis, which affects patients of similar age to GCA is usually confined to the lower limbs and can be differentiated on the basis of the clinical setting and investigations such as the ESR, arteriography and temporal artery biopsy. Takayasu's arteritis' although histologically and arteriographically indistinguishable from GCA, is predominantly a disease of young women. A patient is described who presented with upper limb ischemia. A clinical examination revealed absence of right radial pulses and presence of murmurs at level of the carotids. The blood pressure was unrecordable in the upper right limb. The ESR was 102 mm/hr and the C-reactive protein was 11.66 mg/dl. A selective arteriography of the aortic arch and its branches revealed a right subclavian artery obstruction with good collateral circulation and a left subclavian artery stenosis. The biopsy of left temporal artery showed a typical GCA in acute stage. Treatment with prednisolone 30 mg/day was started and four weeks later, the ESR had fallen to normal. In addition this case confirms that PMR implies a systemic arteritis.

Decrease of CD4-positive T lymphocytes in workers exposed to benzidine and beta-naphthylamine

T lymphocyte subpopulations (CD4+, CD8+, and CD3+ cells), Leu 11a-(CD16) positive lymphocytes, and total lymphocytes in peripheral blood in 52 male dyestuff workers were analyzed to determine the effects of benzidine and beta-naphthylamine on the human immune system. The workers had been exposed prior to 1972 to benzidine and beta-naphthylamine (aromatic amines) at a chemical plant. The dyestuff workers included 27 workers who had engaged in production of aromatic amines (i.e., high-exposure group) and 25 workers who had handled dyestuff at their job (low-exposure group). The total and relative numbers of CD4+ and CD3+ T lymphocytes in the high-exposure group were significantly lower than those found in the control (no-exposure) group (p < .01). Relative--but not total--number of CD16+ lymphocytes in the high-exposure group was significantly higher than in the control group (p < .05). However, there were no significant differences between the low-exposure group and control group with respect to all T lymphocyte subpopulations, CD16+, and total lymphocytes. Perhaps the number of circulating CD4+ T lymphocytes decreases in workers exposed to aromatic amines. It is concluded that measurement of CD4+ lymphocytes provides a useful biological marker of past exposure to aromatic amines.

[A case report--pulmonary cryptococcosis associated with systemic lupus erythematosus and review of 44 cases in Japan]

A case of systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) associated with pulmonary cryptococcosis which was successfully treated with fluconazole (FCZ) and flucytosine (5-FC) is described. A 63-year-old woman who had been treated with steroid for SLE and low dose methotrexate (MTX) for RA was admitted to Jichi Medical School Hospital because of abnormal shadow in the chest X-ray film. Physical examination revealed no abnormality. A chest CT film showed multiple nodular shadows localized in the right lower lobe. An ultrasonically guided trans-cutaneous lung biopsy performed on 10th hospital day established a diagnosis of pulmonary cryptococcosis. Following the treatment with FCZ and 5-FC for a month, her abnormal lung shadows improved and serum cryptococcal antigen level was decreased. A survey of the literature from 1955 to 1990 revealed 44 cases of SLE associated with cryptococcosis in Japan, in addition to our case, most of whom were on corticosteroid therapy. The majority of patients were young women, representing the usual population of patients with SLE. 34 of these patients had cryptococcal meningitis; 22, pulmonary cryptococcosis; 6, sepsis; 6 cutaneous cryptococcosis. Twenty patients died. Deep fungal infections should be considered whenever patients with SLE have fever of unknown origin, diffuse pulmonary infiltrates, or unexplained CNS symptoms.

A seal-less centrifugal pump (Baylor Gyro Pump) for application to long-term circulatory support

We are developing a new centrifugal pump, the Baylor Gyro Centrifugal Pump (Gyro Pump), which can function for more than 2 weeks. The concept of the Gyro Pump is that a one-piece rotor-impeller with embedded permanent magnets, driven directly by a brushless direct current motor stator placed outside, rotates like a "gyroscope," and the rotor-impeller is supported by one pivot bearing at the bottom in accordance with the gyroscopic principle. This concept enables us to eliminate a driving shaft and a seal between the driving shaft and the blood chamber, which results in extending the life of the centrifugal pump. The blood passes through the space between the motor stator and the rotor to the impeller portion. In this preliminary phase, two pivot bearings were applied to support the rotor-impeller at the top and the bottom inside the blood chamber. Both pivot bearings showed less blood trauma and less thrombogenicity in in vitro and in vivo studies. The Gyro Pump is a promising second-generation centrifugal pump for long-term circulatory support in the near future.

Direct imaging of the tricuspid valve annular motions by fiberoptic cardioscopy in dogs. I. Does De Vega's annuloplasty preserve the annular motions?

Applying the technology of direct imaging by fiberoptic cardioscopy, physiologic and pathophysiologic motions of the tricuspid valve anulus were studied in 10 anesthetized normal dogs (control group) and in 9 dogs that had chronic tricuspid regurgitation (TR group). The heart was perfused with transparent modified Tyrode's solution by working heart method, and the anuli, outlined by sutured beads, were observed and recorded on a high-speed video system in real time. Tricuspid valve annular area was calculated at 14 points during the cardiac cycle. The control group was studied in the normal condition, and the tricuspid regurgitation group was studied during four interventions: nontricuspid annuloplasty group and three tricuspid annuloplasty groups with reducing tricuspid valve annular area to 80%, 65%, and 50% of that of the non-tricuspid annuloplasty group by De Vega's procedure. Tricuspid valve annular area in the control group increased by 7% during atrial systole and was reduced by 34% mainly during ventricular systole, in which the free wall annular area and the septal annular area narrowed by an equal 34%. Chronic tricuspid regurgitation lessened tricuspid valve annular area narrowing to 20% in percent reduction (p < 0.01). In the TR group the decrease in tricuspid valve annular area narrowing was attributed mainly to lessened narrowing of the free wall anulus (percent reduction of tricuspid valve annular area, 19%; p < 0.01). The amplitudes in tricuspid valve annular area narrowing were unchanged in the tricuspid annuloplasty groups even when tricuspid valve annular area, was reduced to 50% by De Vega's tricuspid annuloplasty (percent reduction of tricuspid valve annular area, 16%; not significant). These findings suggest that De Vega's tricuspid annuloplasty is a reasonable method that does preserve the physiologic annular motions in the opening and closing mechanism of the tricuspid valve.

Direct imaging of the tricuspid valve annular motions by fiberoptic cardioscopy in dogs with tricuspid regurgitation. II. Does flexible ring annuloplasty preserve the annular motions?

Applying the technology of direct imaging by fiberoptic cardioscopy in a working-heart condition, we studied the tricuspid valve annular motions with flexible rings in nine dogs with chronic tricuspid regurgitation. Three annuloplasty studies with a totally flexible polytetrafluoroethylene ring, an elastic silicone ring, and a rigid metal ring were compared with a nonannuloplasty study. The annuloplasty was performed by reducing tricuspid valve annular area to 65% of that of nonannuloplasty condition. The anuli were observed and recorded on a videotape in real time. The three rings effectively reduced and remodeled the dilated anuli and improved the valve coaptation. The patterns of annular motions with the polytetrafluoroethylene and silicone ring were similar to that of normal anulus; the free wall anulus contracted centripetally, and the septal anulus moved toward the free wall side during systole. Pliability of both the anteroseptal and posteroseptal commissures with the flexible rings made these motions possible. The polytetrafluoroethylene ring followed a natural undulation of the anulus, whereas the silicone and rigid metal rings forced the annular planes to horizontal ones. Percent reductions of tricuspid valve annular area were 25%, 21%, and 23% in the nonannuloplasty, polytetrafluoroethylene, and silicone ring studies, respectively, without significant differences in annular contraction. In contrast, rigid metal rings completely disturbed the annular motions. These findings indicated that the two flexible rings did preserve the physiologic annular motions to the degree that the anuli had in the chronic tricuspid regurgitation condition. Especially, the totally flexible polytetrafluoroethylene ring preserved not only the annular motions but also the natural undulation, which resulted in reinforcing the valve coaptation. We believe that the flexible ring, especially a totally flexible one, is superior to the rigid ring in the aspect of reinforcing the valve coaptation to prevent further regurgitation.

Versatile one-piece total artificial heart for bridge to transplantation or permanent heart replacement

A versatile, one-piece total artificial heart (TAH) system that can be driven by either an electromechanical acutator (EM-TAH) or a pneumatic source (P-TAH) has been developed. The common units for both TAHs are the conically shaped left and right pusher-plate-type pumps (63 ml SV) that sandwich a thin centerpiece (18 mm) having a respective actuator. The EM actuator, mounted in the middle of the centerpiece, consists of a direct-current brushless motor and a roller screw while the pneumatic actuator consists of a low-pressure air source. The outer diameter of the pumping unit is 97 mm with its central thickness being 82 mm; overall volume is 510 cc. The TAH is operated in the left master alternative ejection mode with the left pump fill signal. High-flex-life Hexsyn rubber is used as the diaphragm, and the blood-contacting surface is coated with dry gelatin. The TAH can provide 3-8 L/min flow with a preload of 1-10 mm Hg against 100 mm Hg afterload. Anatomical fit of the pumping unit has been demonstrated in the pericardial space of 26 heart transplant recipients with average body weight of 78 kg. To date, 2 P-TAH and 4 EM-TAH (1 week) implantations were performed in 80-100 kg calves demonstrating excellent anatomical fit, controllability, and biocompatibility. This versatile TAH is suitable for a bridge to transplantation or permanent heart replacement.

CD3+4-8- alpha beta T cell population with biased T cell receptor V gene usage. Presence in bone marrow and possible involvement of IL-3 for their extrathymic development

Analysis of TCR of a series of CD4-8- (double negative; DN) alpha beta T cell lines induced with IL-3 revealed that their V gene usage was biased for V alpha 4 and V beta 2. This has been confirmed in the primary short-term cultures. Thus, IL-3 induced the generation of DN alpha beta T cells with predominant V beta 2 gene expression from the CD4+/CD8+ T cell-depleted spleen or bone marrow (BM) cells of both normal and nude BALB/c mice within 10 days. It was further indicated that the V beta 2+ beta-chain genes contained few junctional N regions in both IL-3-induced primary DN alpha beta T cells and continuous lines. Search for the in vivo counterpart of in vitro IL-3-induced DN alpha beta T cells revealed that BM, but not spleens, of normal BALB/c and B6 mice did contain a significant proportion of DN alpha beta T cells, and that the majority of them expressed V beta 2+ beta-chain genes with few junctional N regions. The presence of V beta 2+ DN alpha beta T cells was similarly observed in the BM of BALB/c nude mice, but their proportion varied markedly among various strains of mice, which was not linked to H-2 haplotypes. The results indicated that V beta 2+ DN alpha beta T cells in the BM represented one of the thymus-independent T cell populations, whose development was under the major histocompatibility Ag complex-unlinked genetic control. TCR of these T cells were shown to be functional as judged by the proliferative response to anti-V beta 2 antibody. Taken together, present results suggested that IL-3 could induce differentiation and/or proliferation of DN alpha beta T cells with uniquely limited repertoire, which existed preferentially in BM in vivo, and implied the possible involvement of extrathymic endogenous ligands as a positive selection force.

CD3+4-8- alpha beta T cell population with biased T cell receptor V gene usage. Presence in bone marrow and possible involvement of IL-3 for their extrathymic development

Analysis of TCR of a series of CD4-8- (double negative; DN) alpha beta T cell lines induced with IL-3 revealed that their V gene usage was biased for V alpha 4 and V beta 2. This has been confirmed in the primary short-term cultures. Thus, IL-3 induced the generation of DN alpha beta T cells with predominant V beta 2 gene expression from the CD4+/CD8+ T cell-depleted spleen or bone marrow (BM) cells of both normal and nude BALB/c mice within 10 days. It was further indicated that the V beta 2+ beta-chain genes contained few junctional N regions in both IL-3-induced primary DN alpha beta T cells and continuous lines. Search for the in vivo counterpart of in vitro IL-3-induced DN alpha beta T cells revealed that BM, but not spleens, of normal BALB/c and B6 mice did contain a significant proportion of DN alpha beta T cells, and that the majority of them expressed V beta 2+ beta-chain genes with few junctional N regions. The presence of V beta 2+ DN alpha beta T cells was similarly observed in the BM of BALB/c nude mice, but their proportion varied markedly among various strains of mice, which was not linked to H-2 haplotypes. The results indicated that V beta 2+ DN alpha beta T cells in the BM represented one of the thymus-independent T cell populations, whose development was under the major histocompatibility Ag complex-unlinked genetic control. TCR of these T cells were shown to be functional as judged by the proliferative response to anti-V beta 2 antibody. Taken together, present results suggested that IL-3 could induce differentiation and/or proliferation of DN alpha beta T cells with uniquely limited repertoire, which existed preferentially in BM in vivo, and implied the possible involvement of extrathymic endogenous ligands as a positive selection force.

Aortic valve replacement for Takayasu's arteritis

We report 12 cases of aortic valve replacement performed for Takayasu's arteritis and discuss the genesis of aortic regurgitation and the clinical outcome after aortic valve replacement. This group of twelve patients who underwent aortic valve replacement between April 1982 and March 1990 included four male and eight female patients, aged 24 to 67 years (mean age 48 years). Preoperative angiography showed systemic multiple stenoocclusive or aneurysmal dilated vascular lesions in addition to aortic regurgitation. The multiple lesions included a lesion in the aortic arch branch in nine (75%), in the pulmonary artery in seven (58%), an aneurysmal dilation in the ascending aorta of more than 6 cm in four (33%), a coronary lesion in four (33%), a thoracic aortic lesion in six (50%), and a lesion in the abdominal aorta and its visceral branch in six (50%). Simple aortic valve replacement alone was performed in two patients and in combination with another operation in ten patients, with aortic root reconstruction in two, ascending aortic plication in three, coronary artery bypass grafting in two, aortic arch branch bypass grafting in one, aortic arch branch bypass grafting and coronary ostium endarterectomy in one, and mitral valve replacement and ascending aortic plication in one. There was no operative death, and only one patient died later, 18 months after the operation, because of secondary amyloidosis. The postoperative recovery of the clinical status and cardiac function was good. Intraoperative observations suggested that aortic valve regurgitation may be caused by an extension of aortitis, although histopathologic examinations of the valve showed nonspecific findings. One of the characteristic problems in Takayasu's arteritis is the necessity for prednisolone administration in some patients preoperatively or postoperatively, or both. We conclude that aortic valve replacement for patients with Takayasu's arteritis is an effective and safe treatment. Our data related to the genesis of aortic regurgitation in Takayasu's arteritis remain insufficient to draw conclusions, and further analysis is planned.

Baylor multipurpose circulatory support system for short- to long-term use

A multipurpose circulatory support system has been developed as both a temporary and permanent device in total artificial hearts (TAHs) and ventricular assist devices (VADs). The multipurpose concept was derived from the development of a totally implantable electromechanical, one-piece TAH. The blood pump is pneumatically driven in short-term use and is electromechanically driven in long-term or permanent use. Both TAH and VAD versions consist of the same components, except for the actuation mechanism. The common components are a compact pumping chamber with the same configuration, a blood contacting surface biolized with gelatin, a pusher-plate, a Hexsyn rubber diaphragm (University of Akron, Akron, OH) and bovine pericardial valves. Both TAHs and VADs have 63 ml of stroke volume, and the VADs are compact compared with other available investigational device exemption devices. Currently, 1 week survival has been achieved using the electromechanical TAH and 2 week survival using the electromechanimcal VAD without anticoagulation. Results suggest that the currently developed system could be applied in varied patients as a temporary device after cardiotomy, a long-term device for bridge to transplantation, or a permanent device for end-stage heart disease.

[Postoperative evaluation of left ventricular peak filling rate and peak ejection rate by radionuclide ventriculography for aortic regurgitation]

Postoperative left ventricular (LV) time-activity curve and the first derivative in radionuclide method were evaluated in 28 patients with aortic regurgitation to clarify the postoperative cardiac function and to determine the adequate timing of operation. Twenty-eight patients were divided into two groups by preoperative echocardiogram. In Group I cases, echo-finding showed LV contractile dysfunction associated with both enlarged LV end-systolic dimension (LVDs) over 5 cm and depressed fractional shortening (%FS) below 25%. In Group II cases, the finding showed compensated cardiac function with relatively small LVDs below 5 cm or not so depressed %FS over 25%. Preoperative diastolic parameter of LV peak filling rate (PFR) in Groups II of 22 cases was depressed in comparison of normal control, although systolic parameters of peak ejection rate (PER) or ejection fraction were mildly depressed. Postoperatively, those parameters of PFR and PER were improved to normal control level (1. PFR: pre op = 206 +/- 73----post op = 311 +/- 79, p less than 0.001 2. PER: pre op = 309 +/- 65----post op = 389 +/- 103 %EDV/sec. p less than 0.001). In contrast, the preoperative parameters of PFR and PER in Group I of 6 cases were strikingly impaired, and post-operative those parameters were not improved to normal level (1. PFR: op = 154 +/- 39----post op = 190 +/- 88 2. PER: pre op = 223 +/- 74----post op = 244 +/- 78 %EDV/sec, NS). No postoperative complications occurred in Group II cases, in contrast, 2 cases in Group I were complicated with low output syndrome or ventricular fibrillation.(ABSTRACT TRUNCATED AT 250 WORDS)

One-stage operation for synchronous primary cancers of the lung and the trachea

A rare combination of synchronous primary adenocarcinoma of the right upper lobe of the lung and adenoid cystic carcinoma of the subglottic trachea was simultaneously managed by lobectomy with lymph node dissection and sleeve resection of the upper trachea through median sternotomy and cervical collar incisions. This combined approach should be a perfectly acceptable one for synchronous tumors of the proximal trachea and of the right upper and middle lobes and left upper lobe of the lung.

Potential clinical applications of the oxygen carrying solutions

Two major areas of research of the oxygen carrying solutions are 1) utilization of hemoglobin and 2) perfluorochemicals. Even though they are not perfect red blood cell substitutes, the "oxygen carrying solutions" have many potential clinical applications because they will reach tissues more easily than normal human red cells and can deliver oxygen directly to tissues. In this paper, important examples of such usages are suggested. Additional clinical and non-clinical applications of the oxygen carrying solutions may be added in the near future.

Interleukin 7 preferentially supports the growth of gamma delta T cell receptor-bearing T cells from fetal thymocytes in vitro

Murine fetal thymus cells were cultured with various interleukins (IL-1, 2, 3, 4, 5, 6, and 7) in the absence or presence of phorbol 12-myristate 13-acetate (PMA), and it was found that only IL-4 and IL-7 induced a prominent proliferative response in the presence of PMA. A large proportion of cells grown in the cultures of fetal thymus cells (days 15 and 17 of gestation) stimulated with PMA plus IL-4 or with PMA plus IL-2 remained CD4-CD8-. In marked contrast, nearly 70% of the cells generated in the cultures of the same fetal thymocytes stimulated with PMA plus IL-7 expressed CD8 on their surface. Approximately 30% of these cells expressed TCR gamma, delta, whereas TCR alpha beta+ cells were virtually undetectable. The cells grown in cultures stimulated with PMA plus IL-7 comprised three populations: CD4-Lyt-2-3-, CD4-Lyt-2 + Lyt-3- and CD4-Lyt-2 + Lyt-3+, and that TCR gamma delta+ T cells were found in all three populations. It was also found that the addition of IL-7 in the culture of adult CD4-CD8- thymocytes on the monolayer of a thymic stromal cell line, which selectively promotes the generation of alpha beta T cells, resulted in the generation of gamma delta T cells. These results strongly suggest that IL-7 plays an important role in the development of gamma delta T cells.

Evaluation of left ventricular early diastolic function after coronary artery bypass grafting relating to myocardial damage

This clinical study was undertaken to evaluate resting left ventricular early diastolic function relating to perioperative myocardial damage after coronary artery bypass graft (CABG) with radionuclide ventriculography. Forty-eight cases undergoing CABG were divided into two groups--Group I: not complicated with perioperative myocardial infarction (PMI), and Group II: complicated with PMI. In group I (42 cases), early diastolic parameters such as peak filling rate (1/3 PFR) and mean filling rate (1/3 FR(m)) during first third diastole were not impaired in the postoperative and follow up periods. In contrast, in Group II (6 cases), early diastolic parameters were significantly decreased to 157 +/- 74% EDV/sec of 1/3 PFR(pre op: 234 +/- 74, p less than 0.05) and 153 +/- 80% EVD/sec of 1/3 FR(m) (pre op: 231 +/- 86, p less than 0.05) in the postoperative period, and these parameters were still decreased in follow up period. The time to peak filling rate, normalized to diastolic time (TPFR/DT) of Group II cases, was severely prolonged in both periods. From these results, the complication of perioperative myocardial infarction was suggested by the decrease of early diastolic function and the prolongation of the time to peak filling rate. Early diastolic function was a more sensitive parameter than systolic function in the detection of impaired cardiac function in those cases with perioperative myocardial damage after CABG.

[A case of primary Sjögren's syndrome presenting as osteomalacia secondary to renal tubular acidosis]

We report a 43-year-old female with primary Sjögren's syndrome (SjS) who presented as osteomalacia due to distal renal tubular acidosis (RTA). Osteomalacia was thought to be a rare complication of RTA in SjS, although it had been often described in association with RTA in general. In 1979, she presented with dry mouth, parotid gland swelling and leg purpura. A diagnosis of primary SjS and hyperglobulinemic purpura was made on the basis of positive staining with Rose Bengal stain, sialography of the parotid gland and histological examination of the salivary gland of the lip. She was admitted to Jichi Medical School Hospital in March 1988 with chest pain. X-ray films revealed pseudofractures of bilateral ribs. Bone scanning showed abnormal multiple accumulation of RI on the same parts. Laboratory studies on admission revealed: GOT 50 IU/ml, GPT 9 IU/ml, ALP 190 IU/ml, LDH 301 IU/ml, BUN 11.0 mg/dl, creatinine 1.0 mg/dl, uric acid 2.7 mg/dl, total protein 7.4 g/dl (gamma globulin 22.3%), sodium 141 mEq/l, potassium 3.7 mEq/l, chloride 106 mEq/l, calcium 8.9 mg/dl, and phosphorus 2.4 mg/dl. Arterial blood gas studies on room air showed: PO2 96.7mmHg, PCO2 35.5mmHg, HCO3-19.1 mEq/l, PH 7.347 and base excess -5.4 mEq/l. The urinalysis showed: specific gravity 1.008, PH 7.0, and no protein and glucose. Immunologically, antinuclear antibody was positive at 1:640 with a speckled pattern. Anti-DNA antibody was negative. Antibodies to SS.A and SS.B were 1:64 and 1:32 respectively. Distal RTA was confirmed by the sodium bicarbonate and NH4Cl loading test.(ABSTRACT TRUNCATED AT 250 WORDS)

High-molecular-weight Ly-5 isoforms expressed on T cells: activation-dependent expression

Interleukin 2 (IL-2)-dependent granular T lymphocyte (GTL) lines derived from murine spleen were shown to express a Ly-5 antigen with the so-called 'B220-epitope' recognized by 6B2 mAbs, which were normally exhibited on B-lineage cells. Immunoprecipitation analysis revealed that the Ly-5 isoform on GTL lines represented the highest-molecular-weight Ly-5 so far described (260 kd), distinct from the B220 isoform on a pre-B cell line (240 kd). The size difference between them was also evident after the endoglycosidase treatment (210 versus 190 kd), strongly suggesting that these Ly-5 isoforms had core proteins of distinct size. Sequential immunoprecipitation by 6B2 and 14.8 mAbs further indicated that the 260 kd Ly-5 on GTL lines predominantly expressed '6B2 epitope' while '14.8 epitope' dominated in the B220 (240 kd) on a pre-B cell line. Northern blot analysis of the Ly-5 transcripts using probes for the known alternative exons failed to show any evidence for mRNA of the 260 kd Ly-5 distinct from that of B220. Polymerase chain reaction analysis, however, suggested that the 260 kd isoform mRNA might be transcribed from a distinct promoter with a yet undefined exon(s). The 6B2+ Ly-5 isoform was hardly detected on normal splenic T cells, but was shown to be induced rapidly on the majority of T cells following IL-2 stimulation in vitro, indicating that this particular Ly-5 isoform behaved as an 'activation antigen' on T cells.(ABSTRACT TRUNCATED AT 250 WORDS)