Effects of human lung fibroblasts on eosinophil degranulation

BACKGROUND

Although eosinophils and fibroblasts are thought to contribute to the mechanisms of chronic asthmatic inflammation, the interaction between eosinophils and fibroblasts has not been thoroughly clarified. We examined eosinophil cationic protein (ECP) release from human eosinophils cultured in the presence of human lung fibroblast HFL-1.

METHODS

Eosinophils from healthy donors were cultured with or without C5a for 16 h in the presence of human fetal lung fibroblasts which had previously been incubated with or without TNF for 4 h. ECP in supernatants was measured by RIA.

RESULTS

ECP release was potentiated only when both eosinophils and fibroblasts were activated by C5a and TNF, respectively, while it was not significantly potentiated when either eosinophils or fibroblasts were activated. Paraformaldehyde fixation of fibroblasts had some suppressive effect on ECP enhancement, and mAb against GM-CSF partly inhibited ECP enhancement. Coculture of eosinophils and fibroblasts with stimulus treatment resulted in the enhancement of both eosinophil adhesion and ECP release. The potentiation of ECP release was partially inhibited by anti-ICAM-1 mAb, anti-CD18 mAb, and anti-CD29 mAb, which caused partial and comparable inhibition of the enhancement of eosinophil adhesion.

CONCLUSIONS

This study suggests that the activation of fibroblasts may have some role in the potentiation of ECP release from cocultured eosinophils, and that adhesion of eosinophils to fibroblasts may partly be involved in the mechanism of ECP potentiation.

T-cell-mediated regulation of osteoclastogenesis by signalling cross-talk between RANKL and IFN-gamma

Bone resorption is regulated by the immune system, where T-cell expression of RANKL (receptor activator of nuclear factor (NF)-kappaB ligand), a member of the tumour-necrosis factor family that is essential for osteoclastogenesis, may contribute to pathological conditions, such as autoimmune arthritis. However, whether activated T cells maintain bone homeostasis by counterbalancing the action of RANKL remains unknown. Here we show that T-cell production of interferon (IFN)-gamma strongly suppresses osteoclastogenesis by interfering with the RANKL-RANK signalling pathway. IFN-gamma induces rapid degradation of the RANK adapter protein, TRAF6 (tumour necrosis factor receptor-associated factor 6), which results in strong inhibition of the RANKL-induced activation of the transcription factor NF-kappaB and JNK. This inhibition of osteoclastogenesis is rescued by overexpressing TRAF6 in precursor cells, which indicates that TRAF6 is the target critical for the IFN-gamma action. Furthermore, we provide evidence that the accelerated degradation of TRAF6 requires both its ubiquitination, which is initiated by RANKL, and IFN-gamma-induced activation of the ubiquitin-proteasome system. Our study shows that there is cross-talk between the tumour necrosis factor and IFN families of cytokines, through which IFN-gamma provides a negative link between T-cell activation and bone resorption. Our results may offer a therapeutic approach to treat the inflammation-induced tissue breakdown.

Malignant schwannoma with melanocytic differentiation arising in a patient with neurofibromatosis

A 50-year-old woman with von Recklinghausen's disease, but not Carney's complex, presented with a 1-year history of a hard subcutaneous mass on her right hip and right inguinal lymphadenopathy. Histological and immunohistochemical studies of the tumour revealed schwannian and melanocytic characteristics. Local recurrence without distant metastases was observed 5 years later. Although the diagnosis of malignant schwannoma with melanocytic differentiation, rather than neurotropic melanoma, was made for the primary tumour, based on the clinicohistopathological and ultrastructural findings, the overall clinical course in this case did not seem incompatible with malignant melanocytic schwannoma.

Bovine lactoperoxidase and its recombinant: comparison of structure and some biochemical properties

Biochemical properties of bovine lactoperoxidase isolated from milk and recombinant bovine lactoperoxidase expressed by Chinese hamster ovary cells were compared. The natural and recombinant lactoperoxidases showed the same conformational features as determined by circular dichroism (CD) measurements. The alpha-helix, beta-structure, and unordered structure contents were found to be 17. 8, 54.2, and 28.0% for the natural lactoperoxidase and 18.6, 50.1, and 31.3% for the recombinant lactoperoxidase, respectively. The microenvironments of aromatic amino acid residues in both lactoperoxidases seemed to be the same, although the CD spectral band due to the Soret band differed slightly. A difference in the pH-dependent spectral changes of absorbance at 413 nm was observed. From a pepsin hydrolysate of lactoperoxidase, a heme-binding peptide was isolated by reverse-phase HPLC and its amino acid sequence was examined.

Developmentally regulated, alternative splicing of the Rpn10 gene generates multiple forms of 26S proteasomes

The 26S proteasome is a multisubunit protein- destroying machinery that degrades ubiquitin-tagged proteins. To date only a single species of Rpn10, which possibly functions as a multiubiquitin chain-binding subunit, has been identified in various organisms. Here we report that mouse Rpn10 mRNAs occur in at least five distinct forms, named Rpn10a to Rpn10e, and that they are generated from a single gene by developmentally regulated, alternative splicing. Rpn10a is ubiquitously expressed, whereas Rpn10e is expressed only in embryos, with the highest levels of expression in the brain. Both forms of Rpn10 are components of the 26S proteasome, with an apparently similar affinity for multiubiquitylated [(125)I]lysozyme in vitro. However, they exert markedly divergent effects on the destruction of B-type cyclin in Xenopus egg extracts. Thus, the 26S proteasome occurs in at least two functionally distinct forms: one containing a ubiquitously expressed Rpn10a and the other a newly identified, embryo-specific Rpn10e. While the former is thought to perform proteolysis constitutively in a wide variety of cells, the latter may play a specialized role in early embryonic development.

Tissue selectivity of KMD-3213, an alpha(1)-adrenoreceptor antagonist, in human prostate and vasculature

PURPOSE

We evaluated the binding and functional affinity of KMD-3213 and other alpha 1-adrenoceptor (AR) antagonists such as prazosin or tamsulosin, to compare the tissue selectivity of these antagonists between human prostate and vasculature.

MATERIALS AND METHODS

In the binding experiments, saturation experiments using [3H]-KMD and [3H]-prazosin (PZ) were performed, and competition of [3H]-PZ binding by antagonists was also examined in human prostatic and aortic membranes. In the functional study, contractile responses to noradrenaline were evaluated in human prostate and mesenteric artery.

RESULTS

[3H]-PZ bound to human prostatic and aortic membranes with subnanomolar affinity. [3H]-KMD also bound to human prostate, with higher affinity than [3H]-PZ; whereas it did not bind sufficiently to human aorta. Competition of [3H]-PZ binding revealed that KMD-3213 had more than 200-fold higher affinity for human prostate than for aorta. Binding profiles of antagonists revealed that human prostate predominantly expressed alpha 1A-AR, whereas human aorta expressed alpha 1B-AR mainly. In functional experiments, KMD-3213 potently inhibited the noradrenaline-induced contraction in human prostate as potently as tamsulosin, although prazosin showed relatively low affinity. Comparing these functional affinities with those in the mesenteric artery, only KMD-3213 exhibited substantial tissue selectivity, showing more than 100-fold higher affinity for human prostate than for mesenteric artery. Functional affinity of each antagonist suggested that noradrenaline-induced contractions were mainly mediated by alpha 1L-AR in the human prostate and by alpha 1B-AR in the mesenteric artery.

CONCLUSION

These results suggest that KMD-3213 is a substantially prostate-selective alpha 1-AR antagonist in human tissues compared with other alpha 1-AR antagonists.

Efficiency enhancement of long-range energy transfer by sequential multistep FRET using fluorescence labeled DNA

The efficiency of long-range (ca. 80 A) fluorescence energy transfer was enhanced about 1.5 times by a third chromophore located midway between two chromophores. A third chromophore should act like a relay station in sequential multistep energy transfer.

[Results of valve surgery combined with CABG]

During recent 8 years, combined procedures of valve surgery and coronary artery bypass grafting (CABG) were performed in fifty-five patients at Omiya Medical Center. AVR (31 cases), MVR (12 cases), MVP (8 cases), DVR (1 case), TVR (1 case), TAP (2 cases) were performed with the average of 2.0 bypass graftings in this series. Five patients died due to organ ischemia (3 cases), cerebral embolism and heart failure. Organ ischemia occurred in dialysis patients and the results of combined surgery in dialysis patients were unsatisfactory (3/5 cases, mortality rate is 60%). On the other hand, the results of combined surgery in non-dialysis patient is reasonable (2/50 cases, mortality rate is 4%). Before the combined surgery in dialysis patient, careful analysis of surgical risk including organ ischemia is needed and avoiding the prolonged perfusion time is important to achieve a successful surgical result.

Synthesis and bioactivities of novel piperidylpyrimidine derivatives: inhibitors of tumor necrosis factor-alpha production

New piperidylpyrimidine derivatives, including quinazolines, were prepared, and their abilities to inhibit TNF-alpha production evaluated. Some compounds showed potent inhibitory activity in mouse macrophages stimulated with LPS. The synthesis and structure activity relationships of these compounds are described.

Resuscitation and circulatory support using extracorporeal membrane oxygenation for fulminant pulmonary embolism

Fulminant pulmonary embolism (PE) with circulatory collapse is associated with a high mortality rate due to acute right ventricular failure and hypoxia. Immediate and appropriate resuscitation and circulatory support in the perioperative period is mandatory to prevent sudden death. Extracorporeal membrane oxygenation (ECMO) was recently introduced for extracorporeal life support in patients with circulatory collapse and has provided an excellent outcome. We report on the effectiveness of ECMO support for fulminant PE. Seven patients were placed on veno-arterial ECMO for circulatory collapse caused by fulminant PE refractory to conventional treatment. After resuscitation, all patients underwent pulmonary angiography, and thrombolytic therapy was administered in all 7 patients under ECMO support. Three patients who did not improve by thrombolysis underwent embolectomy with standard cardiopulmonary bypass. Two thrombolysis and 2 surgery patients were weaned from bypass and survived. The duration of support ranged from 18-168 h (mean = 67.8 +/- 67.1 h), with maximum bypass flow rates of 2.0-4.5 (mean = 3.5 +/- 0.9). There were no device-related complications during support. In total, 4 patients (57%) were successfully weaned from support and discharged from the hospital in good condition. All patients who survived required prolonged support (27, 82, 151, and 168 h). We conclude that resuscitation and circulatory support using ECMO can be effective, life-saving measures in cases of circulatory collapse caused by fulminant PE.

Occurrence of a transcription factor, signal transducer and activators of transcription 3 (Stat3), in the postsynaptic density of the rat brain

Distribution of a signal transducer and activators of transcription 3 (Stat3) was examined in the rat brain. Immunoreactivity was distributed in the neurons, as well as glia cells, throughout the rat brain. Western blotting of subcellular fractions showed distribution in the synaptic fractions (synaptosome, synaptic plasma membrane, and postsynaptic density, PSD). The occurrence of Stat3 in the synaptic site, especially in the PSD, was confirmed by immunoelectron microscopic examination. The PSD fraction had an activity that phosphorylated Stat3 at the tyrosine-705 site, which was confirmed by both Western blotting and immunoprecipitation. The PSD fraction also had a janus kinase 2 (Jak2)-like molecule, Jak2, believed to phosphorylate Stat3. These results indicate that the Jak2/Stat3 signaling system, a major pathway of cytokine signaling in the immune response system, may also play a role at the postsynaptic sites.

Altered distribution and density of myocardial beta-adrenoceptors during acute rejection in rats

BACKGROUND

A better understanding of altered expression of myocardial beta-adrenoceptors can facilitate the diagnosis of early and late acute rejection of heart transplants.

METHODS

We submitted rats to heterotopic heart transplantation (iso- and allografts) of which one of each were treated with or without cyclosporin A for 4, 7, and 14 days (n=5, respectively). The cardiac sections were incubated in vitro with [3H]CGP 12177, or the hearts were labeled in vivo by intravenous injection of [3H]CGP 12177. Autoradiographic images of both were analyzed digitally and compared with histologic findings.

RESULTS

Beta-adrenoceptor distribution in native hearts and isografts was homogeneous, but highly differential distribution and density in allografts were observed in the left and right ventricular walls and in the interventricular septum despite treatment with cyclosporin A. High-density areas in the progressive course of acute rejection are commonly associated with up-regulation of beta-adrenoceptors in apparently viable myocytes, although histologic findings confirmed many infiltrating mononuclear cells. Low-density areas, which were identified in the right and left ventricular walls as early as 4 days after transplantation, correlated with derangement of myocytes, which was suggestive of early acute rejection. The images obtained by in vivo technique were comparable to in vitro images.

CONCLUSIONS

The alteration of beta-adrenoceptor expression in allografts showed a close relationship with the severity of acute rejection, and the techniques employed in this model were useful in our study of the rejection process and in detecting early and late acute rejection in the rat.

Distribution of alpha1-adrenoceptor subtype mRNA and identification of subtype responsible for renovascular contraction in human renal artery

This study was intended to quantify the amounts of the alpha1-adrenoceptor subtype mRNAs in human renal artery and to demonstrate the distribution of receptor subtypes responsible for the contraction of the renal artery. RNase protection assay showed that the mean amount of alpha1a mRNA was much greater than that of alpha1b or alpha1d mRNAs in both the main and branch renal arteries. However, the abundance of alpha1a mRNA in human renal artery was much less than in our previous data in the prostate. In situ hybridization showed that all alpha1 subtype mRNAs were localized in the smooth muscle cells of the tunica media of the artery, and the distribution pattern of these three mRNAs in the main artery was the same as in the branch artery. However, the intensity of signals for alpha1d and alpha1b antisense RNAs probes was lower than that for the alpha1a antisense RNA probe. In the functional study, concentration-response curves to noradrenaline pretreated with KMD-3213, an alpha1A/L-adrenoceptor selective antagonist, seemed to be biphasic in nature. Chloroethyclonidine (CEC) failed to inactivate the noradrenaline-induced contraction, and prazosin showed relatively low affinity with a pA2 value of 8.8. These data suggest that the alpha1A/L-adrenoceptor mediates primarily those responses to noradrenaline in this artery. The other alpha1-adrenoceptor subtypes could also mediate the secondary contractile response to noradrenaline in this artery.

Electrophysiological effect of l-cis-diltiazem, the stereoisomer of d-cis-diltiazem, on isolated guinea-pig left ventricular myocytes

l-cis-Diltiazem, the stereoisomer of the L-type Ca(2+) channel blocker d-cis-diltiazem, protects cardiac myocytes from ischemia and reperfusion injury in the perfused heart and from veratridine-induced Ca(2+) overload. We determined the effect of l-cis-diltiazem on the voltage-dependent Na(+) current (I(Na)) and lysophosphatidylcholine-induced currents in isolated guinea-pig left ventricular myocytes by a whole-cell patch-clamp technique. l-cis-Diltiazem inhibited I(Na) in a dose-dependent manner without altering the current-voltage relationship for I(Na) (K(d) values : 729 and 9 microM at holding potentials of -140 and -80 mV, respectively). A use-dependent block of I(Na), the leftward shift of the steady-state inactivation curve and the delay of recovery from inactivation suggest that l-cis-diltiazem has a higher affinity for the inactivated state of Na(+) channels. In addition to I(Na), the lysophosphatidylcholine-induced currents were inhibited by l-cis-diltiazem in a similar concentration range. It is suggested that inhibition of both Na(+) channels and lysophosphatidylcholine-activated non-selective cation channels contributes to the cardioprotective effect of l-cis-diltiazem.

Kinetics of cytokine gene expression during the in vitro CTL induction against a murine nonimmunogenic tumor

BACKGROUND

The study of the local environment around tumors, including cellular and endogenous cytokine kinetics may improve our understanding of the biological process occurring during the CTL induction.

MATERIALS AND METHODS

The expression kinetics of ten cytokine genes and immune cell subsets were examined by a RT-PCR and immunohistochemistry using a nonimmunogenic murine tumor and its immunogenic variant (A7).

RESULTS

In a mixed lymphocyte-parent tumor cell culture (MLTC) using in vivo A7-immunized spleen cells, where CTL induction was confirmed on day 5 of cultivation, IL-6 gene expression was promptly activated at 12 h, IL-2 and IL-4 gene expression was prominently up-regulated on days 1 and 2, and then IL-10 and TGF-beta gene expression was down-regulated from day 2 onward. In contrast, in a MLTC using non-immunized spleen cells (a CTL non-induction model), no prominent upregulation of the IL-6, IL-2 or IL-4 gene was detected, and expression of the IL-10 and TGF-beta genes increased steadily. Although numerous dendritic cells were observed in the A7 immunized spleen tissue, lower numbers of dendritic cells were evident in the non-immunized spleen tissue.

CONCLUSIONS

A cellular environment that includes the presence of dendritic cells and a cytokine environment that involves the timely production of IL-6, IL-2, and IL-4, and subsequent inhibition of the immunosuppressive cytokines IL-10 and TGF-beta, appear to play an important role in induction of CTL in this model.

Purification and some characteristics of enterocin ON-157, a bacteriocin produced by Enterococcus faecium NIAI 157

Bacteriocin-like activity (BLA) was screened in 690 strains of lactic acid bacteria isolated from plant materials such as silages and fermented vegetables. Among them, a strain identified as Enterococcus faecium NIAI 157 showed a clear BLA against the indicator strain, Ent. faecium IFO 13712. The proteinaceous nature and antimicrobial activity against closely related species strongly indicated that this BLA was a bacteriocin and was designated enterocin ON-157. The bacteriocin activity of this strain was extracellularly produced in the logarithmic growth phase in MRS broth and purified by ultrafiltration, ammonium sulphate precipitation and cation-exchange chromatography. Purified enterocin ON-157 had a molecular weight of approximately 2500 Da in SDS-PAGE analysis and was easily inhibited by treatment with alpha-amylase and proteolytic enzymes. Enterocin ON-157 had a bactericidal mode of action and inhibited the growth of the enterococci, Lactobacillus sake and Listeria monocytogenes. Enterococcus faecium NIAI 157 harboured two plasmids, 49.0 kb and 43.7 kb, and a variant missing a larger plasmid by curing with novobiocin lost the bactriocin activity.

Growth retardation in mice lacking the proteasome activator PA28gamma

The proteasome activator PA28 binds to both ends of the central catalytic machine, known as the 20 S proteasome, in opposite orientations to form the enzymatically active proteasome. The PA28 family is composed of three members designated alpha, beta, and gamma; PA28alpha and PA28beta form the heteropolymer mainly located in the cytoplasm, whereas PA28gamma forms a homopolymer that predominantly occurs in the nucleus. Available evidence indicates that the heteropolymer of PA28alpha and PA28beta is involved in the processing of intracellular antigens, but the function of PA28gamma remains elusive. To investigate the role of PA28gamma in vivo, we generated mice deficient in the PA28gamma gene. The PA28gamma-deficient mice were born without appreciable abnormalities in all tissues examined, but their growth after birth was retarded compared with that of PA28gamma(+/-) or PA28gamma(+/+) mice. We also investigated the effects of the PA28gamma deficiency using cultured embryonic fibroblasts; cells lacking PA28gamma were larger and displayed a lower saturation density than their wild-type counterparts. Neither the expression of PA28alpha/beta nor the subcellular localization of PA28alpha was affected in PA28gamma(-/-) cells. These results indicate that PA28gamma functions as a regulator of cell proliferation and body growth in mice and suggest that neither PA28alpha nor PA28beta compensates for the PA28gamma deficiency.

Cytotoxicity and mutagenicity of UVB assessed using cultured rat fibroblast

A retroviral vector carrying both positive (neo) and negative (herpes simplex virus thymidine kinase or HSV-tk) selection markers was constructed as a substrate for mutational assay in mammalian cells. Using a population of rat fibroblast cells carrying a single copy per cell of retroviral DNA randomly integrated in their chromosomes, we examined the cytotoxic and mutagenic activities of ultraviolet light (UV) at four wavelengths (254, 290, 300, and 320 nm). The action spectra for these activities are similar to some of the previously reported spectra for photochemical DNA modifications, erythema, cell killing, and mouse skin carcinogenesis, except at 290 and 320 nm. At 290 nm, no significant mutagenicity was observed. At 320 nm, both cytotoxic and mutagenic activities were 10 times higher than the values expected from the absorption spectrum for DNA and the action spectrum for bacterial inactivation and mutagenesis. Structural comparison of some of the HSV-tk mutants obtained after irradiation with 300 and 320 nm UV revealed partially different patterns of mutation specificity, suggesting the involvement of multiple molecular mechanisms in the genotoxicity associated with this range of UV.

Epidermolysis bullosa simplex associated with muscular dystrophy: phenotype-genotype correlations and review of the literature

BACKGROUND

Epidermolysis bullosa simplex associated with muscular dystrophy (EBS-MD; OMIM# 226670) is an autosomal recessive disorder caused by genetic defects in the plectin gene. Because EBS-MD is relatively rare, and gene defects have been elucidated only in a limited number of patients, the precise phenotype-genotype correlations have not yet been fully elucidated.

OBJECTIVE

The purpose of this study was to define clinical features of EBS-MD and to clarify its phenotype-genotype correlations.

METHODS

Clinical, ultrastructural, immunohistochemical, and molecular features of 4 unrelated Japanese patients with EBS-MD were recorded. In addition, 6 cases with defined plectin gene mutations reported in the literature were reviewed.

RESULTS

In skin of the EBS-MD patients, the blister formation always occurs just above the hemidesmosomes, and expression of plectin is absent or markedly reduced in all cases examined. All 10 patients, including 6 cases in the literature, showed generalized blistering at birth or soon thereafter, and experienced nail deformities. In addition, decayed teeth (5 cases), urethral strictures (3), mild palmoplantar hyperkeratosis (2), infantile respiratory complications (2), alopecia (1), and laryngeal webs (1) were present. All 8 patients who were older than 9 years demonstrated considerable muscle weakness, and the majority of them ended up being wheelchair bound. Among the 10 patients, 7 were products of consanguineous marriage, 9 have premature termination codon (PTC) mutations in both alleles of the plectin gene, and 7 cases were homozygous for the mutation. One patient who is homozygous for a 2719del9 in-frame deletion mutation that resulted in elimination of 3 amino acids, QEA, could still walk at the age of 46 and showed milder clinical severity.

CONCLUSION

EBS-MD reveals clinical features not only characteristic of EBS and MD, but also other manifestations including urethral, dental, and respiratory complications. The majority of patients are products of consanguineous marriage and have homozygous plectin gene mutations. Whereas patients with PTC mutations in both alleles typically showed severe clinical features of EBS-MD and ended up being wheelchair bound, a homozygous patient for an in-frame deletion mutation showed positive, yet attenuated, plectin expression and milder clinical phenotype. Thus plectin immunofluorescence, combined with identification of the underlying plectin mutations, is of value in predicting the severity of the muscle involvement that occurs later in life of patients with EBS-MD.

Prevention of cerebral vasospasm by a novel endothelin receptor antagonist, TA-0201

This study was designed to examine the preventive effect of a novel endothelin (ET)-receptor antagonist TA-0201 on the cerebral vasospasm in a canine double-hemorrhage model. TA-0201 (10(-9)-10(-7) M) inhibited ET-1-induced vasoconstriction in the isolated canine basilar artery without endothelium in a concentration-dependent manner. Its pA2 value was 9.2 (ET(A) antagonism). In a canine double-hemorrhage model, intravenous treatment with TA-0201 (3 mg/kg, twice a day for 7 days) ameliorated the basilar artery narrowing significantly on day 7 compared with that in nontreated dogs. The reductions of the basilar artery diameter were 26.1+/-3.9% and 40.5+/-4.1% with and without TA-0201 treatment, respectively (p<0.05). Histologic study on day 7 indicated that treatment with TA-0201 inhibited vessel-wall damage such as disintegration of endothelium architecture and degeneration of medial smooth-muscle cells. We conclude that intravenous treatment with TA-0201 prevents the development of cerebral vasospasm and accompanying pathologic changes of the vessel wall, probably through blockade of ET(A) receptors.

Autolysis of the proteinase from Pseudomonas fluorescens

The gene encoding the proteinase from Pseudomonas fluorescens was cloned and sequenced in an effort to identify the cleavage sites involved in its autolysis at 50 degrees C. A single open reading frame consisting of 1449 nucleotides, encoding a protein of 482 amino acids, was found. Analysis of the N-terminal amino acid sequence of the purified proteinase indicated the presence of a prosequence consisting of 13 amino acid residues. The molecular weight of the mature protein was calculated as 48,900 based on the deduced amino acid sequence, which was consistent with that of the purified proteinase as determined by sodium dodecylsulfate-PAGE. Greater than 90% loss of proteolytic activity was observed upon heating at 50 degrees C for 2 min compared with the unheated enzyme. Incubation of the proteinase at 50 degrees C led to disappearance of the intact enzyme, as shown by sodium dodecyl sulfate-PAGE, whereas it was stable in the presence of the protease inhibitor o-phenanthroline. Autolytic fragments were fractionated by reverse-phase HPLC and subjected to N-terminal amino acid sequence analysis in an effort to determine the cleavage sites. The cleavage profile was not definitive; however, amino acid residues with small side chain groups, such as glycine or alanine, were frequently found adjacent to the cleavage sites.

Presence of up-stream and downstream components of a mitogen-activated protein kinase pathway in the PSD of the rat forebrain

We previously reported the presence of Erk2 type mitogen-activated protein kinase (MAPK) and enrichment of its substrates in the post-synaptic density (PSD) fraction, and suggested a role for MAPK in the synaptic transmission and its modulation [Suzuki, T., Okumura-Noji, K., Nishida, E., ERK2-type mitogen-activated protein kinase (MAPK) and its substrates in post-synaptic density fractions from the rat brain, Neurosci. Res., 22 (1995) 277-285.]. In this paper, synaptic localization of the upstream and downstream components of a MAPK cascade was examined. We found that RSK1, Sos1, N-Shc 66 kDa, N-Shc 52 kDa, and Grb2 were present in the PSD fraction, and cPLA(2) was present in the synaptic plasma membrane fraction. RSK2, Sos2, and N-Shc 46 kDa were not present in the PSD fraction. Post-synaptic localization of RSK1 and Sos1 was confirmed by immunohistochemical examination at the electron microscopic level: the two immunoreactivities were localized in the PSDs, both in the spines and dendrites. These results suggest that all the MAPK cascade components examined were associated with PSD or the synaptic plasma membrane, suggesting the role(s) of the MAPK cascade for synaptic transmission and its regulation at post-synaptic sites.

Characteristics of heterogeneity in the expression of vasoconstriction in response to N(G)-monomethyl-L-arginine in isolated canine arteries

We characterized the contractile effect of a nitric oxide (NO) synthase inhibitor, N(G)-monomethyl-L-arginine (L-NMMA), in isolated canine arteries. L-NMMA induced a heterogenous response: potent vasoconstriction in the cerebral arteries, and weak or no vasoconstrictor responses in different peripheral arteries. The vasoconstriction of the cerebral artery was inhibited by L-arginine but not D-arginine. L-NMMA (1(-4) M) caused a 53% decrease in guanosine 3'5'-cyclic monophosphate (cGMP) levels in the cerebral artery, but it was not significant compared with that in peripheral arteries. The L-NMMA-induced vasoconstriction was inhibited by diltiazem and nicardipine, and the heterogeneity was mimicked by treatment with charybdotoxin, a Ca2+-activated K+ (BK(Ca)) channel blocker, channels which are regulated by NO/cGMP. Both L-NMMA and charybdotoxin caused a potent vasoconstriction in the mesenteric artery precontracted with 20 mM KCl. 1 H-[1,2,4]oxadiazolo[4,3-alpha] quinoxalin-1-one (ODQ) (10(-5) M), a selective guanylate cyclase inhibitor, caused vasoconstriction in the presence of nitroprusside in the endothelium-denuded basilar artery, but not in the endothelium-denuded mesenteric artery. In conclusion, LNMMA-induced heterogenous vasoconstriction was due to the different sensitivities of vascular smooth muscles to NO/cGMP. The heterogeneity may result from a difference in the basal state of ion channels such as the voltage-dependent Ca2+ channel and the BK(Ca) channel in vascular smooth muscles.

Displacement and stress distribution in the temporomandibular joint during clenching

The aim of this study was to analyze biomechanical reactions in the mandible and TMJ during clenching under various restraint conditions. A three-dimensional finite element model of the mandible, including the TMJ, was created for test purposes. The results were as follows: (1) Under any restraint conditions, displacement was greatest on the surface of the condyle and less on the articular disc and the surface of the glenoid fossa, in that order. Resultant stresses followed the same trend. (2) Displacement and stress were greatest when the lower central incisor was restrained and attenuated as the posterior teeth were restrained. Because the biomechanical reaction of the TMJ during clenching was greatest when the lower central incisor was restrained, premature contact of these teeth may be one of the factors involved in the initiation of temporomandibular arthrosis.

Local injection of recombinant human stem cell factor promotes human skin mast cell survival and neurofibroma cell proliferation in the transplanted neurofibroma in nude mice

We studied the effects of stem cell factor (SCF) on human skin mast cell (HSMC) survival and the proliferation of neurofibroma (NF) cells in transplanted NF in nude mice. Small pieces of cutaneous NF from a patient with von Recklinghausen's disease were transplanted subcutaneously into nude mice. Recombinant human SCF (10 or 100 ng) was injected six or seven times around the NF transplantation sites over 11 days (i.e. every other day). The number of HSMCs was reduced in vehicle-injected NF compared to the amount present before transplantation. In contrast, NF-transplanted animals that were injected with SCF (10 or 100 ng) showed preservation of mast cell numbers in the tissue. Using computerized image analysis, mast cell size in SCF-treated NF transplants was significantly altered (larger at the 10 ng dose, and smaller at the 100 ng dose) compared with the size before transplantation or in vehicle-injected tissue. Furthermore, at the higher SCF dose (100 ng) PCNA-positive NF cells showed a significant increase. These results indicate that HSMCs in transplanted NF tissue retain their capacity to respond to SCF in vivo, and that SCF contributes to the regulation of both HSMC survival and size in cutaneous NF. In addition, activated HSMCs induced by SCF may be involved in the growth of cutaneous NF in von Recklinghausen's disease. Thus, this experimental model may be useful in the study of the cellular interactions between HSMCs and other stromal cells in cutaneous NF.

Determination of linezolid in plasma by reversed-phase high-performance liquid chromatography

An HPLC-UV method was developed for assay of linezolid in dog, rat, mouse, and rabbit plasma. Linezolid and the internal standard were extracted on a solid phase cartridge (SPE) and separated on a reversed-phase column (C8, 4.6x150 mm, 5 microm) with 20% acetonitrile in water as mobile phase. The SPE quantitatively recovered linezolid and the internal standard from plasma samples. The chromatographic peak height ratio or peak area ratio based on UV absorbency at 251 nm was used for quantitative analysis. The assay procedures were simple and the assay was specific and had adequate precision and accuracy. Calibration standards with concentrations over the range of 0.01 20 microg/ml were validated for routine sample analysis to support the pharmacokinetic and toxicology studies with linezolid in dog, rat, mouse, and rabbit. Analysis of quality control samples showed the coefficients of variation were usually <10% and the measured and theoretical concentrations differed by <10% in most assays. Linezolid in the plasma samples was stable when stored at below -20 degrees C for at least 63 days, at room temperature (22-23 degrees C) for up to 24 h, and after three freeze-thaw cycles. This HPLC method has been successfully used in multiple laboratories to assay plasma samples from pharmacokinetic and toxicology studies with linezolid in the animal species.

Role of endothelin in deterioration of heart failure due to cardiomyopathy in hamsters: increase in endothelin-1 production in the heart and beneficial effect of endothelin-A receptor antagonist on survival and cardiac function

BACKGROUND

We previously reported that chronic endothelin (ET) receptor blockade ameliorated the survival rate and cardiac hemodynamics in rats with chronic heart failure (CHF) due to myocardial infarction. However, it remains unclear whether ET-1 is involved in the pathophysiology of cardiomyopathy, which is one of the major causes of CHF. Accordingly, we investigated the production of ET-1 in the heart and the effect of chronic ETA receptor blockade on survival rate and cardiac function in the Bio 14.6 hamster, which is an idiopathic model of CHF caused by cardiomyopathy.

METHODS AND RESULTS

We used 52-week-old Bio 14.6 cardiomyopathic hamsters and age-matched F1b normal hamsters. The expression of preproET-1 mRNA and the ET-1 level in the hearts were markedly higher in the cardiomyopathic hamsters than in the normal hamsters. The cardiomyopathic hamsters showed severe CHF, illustrated by lower left ventricular (LV) +dP/dt/Pmax and right ventricular (RV) +dP/dt/Pmax and by higher LV end-diastolic pressure (EDP), RVEDP, and central venous pressure compared with the normal hamsters. Long-term (9 weeks) treatment with an ETA antagonist (TA-0201, 1.3 mg. kg-1. d-1) markedly increased survival of cardiomyopathic hamsters (untreated, 16%; TA-0201-treated, 65.2%; P<0.001). After 6 weeks of treatment, LV +dP/dt/Pmax and RV +dP/dt/Pmax were significantly higher and LVEDP and RVEDP were lower in the TA-0201-treated group than in the untreated group, suggesting that chronic TA-0201 treatment effectively prevented deterioration of cardiac dysfunction.

CONCLUSIONS

In the cardiomyopathic hamsters with CHF, the production of ET-1 in the heart was markedly increased, and chronic ETA receptor blockade greatly ameliorated survival and cardiac dysfunction. These results suggest that ET-1 plays an important role in the deterioration of CHF caused by cardiomyopathy, and ETA antagonists may exert therapeutic effects in CHF due to cardiomyopathy.

New alpha1-adrenoceptor antagonist, JTH-601, shows more than 10 times higher affinity for human prostates than arteries

PURPOSE

We compared the affinities of a new alpha1-adrenoceptor (AR) antagonist, JTH-601 with those of several alpha1-AR antagonists in human prostates and arteries.

RESULTS

In the functional study, noradrenaline produced concentration-dependent contractions in human prostates and mesenteric arteries. The pA2/pKB values for the antagonists in the human prostate were 9.78 for tamsulosin, 8.84 for JTH-601, 8.39 for WB4101, 8.23 for prazosin, 8.12 for JTH-601-G1 (a main metabolite of JTH-601 in human) and 6.57 for BMY7378. Compared these affinities with those in the mesenteric artery, only JTH-601 and JTH-601-G1 exhibited unique uroselectivity, showing 10- to 20-fold higher affinity for the human prostate than for mesenteric artery. The affinity profile of these antagonists suggested that the noradrenaline-induced contractions in the human prostate and the mesenteric artery were mediated by the alpha1L-AR and alpha1B-AR, respectively. In the competition binding study, the pharmacological profiles of the antagonists against [3H]-prazosin were examined in the human prostate and aorta. The resulting pKi values for JTH-601 and JTH-601-G1 were also approximately 10- to 20-fold higher for the human prostate than for the human aorta.

CONCLUSION

These results have suggested that JTH-601 and JTH-601-G1 are unique uroselective alpha1-AR antagonists that show higher affinity for the human prostate than for the human arteries.

Splice acceptor site mutation of the transporter associated with antigen processing-1 gene in human bare lymphocyte syndrome

Expression of histocompatibility leukocyte antigen (HLA) class I molecules on the cell surface depends on the heterodimer of the transporter associated with antigen processing 1 and 2 (TAP1 and TAP2), which transport peptides cleaved by proteasome to the class I molecules. Defects in the TAP2 protein have been reported in two families with HLA class I deficiency, the so-called bare lymphocyte syndrome (BLS) type I. We have, to our knowledge, identified for the first time a splice site mutation in the TAP1 gene of another BLS patient. In addition, class I heavy chains (HCs) did not form the normal complex with tapasin in the endoplasmic reticulum (ER) of the cells of our patient.

The mechanism of the increasing action of TA-993, a new 1,5- benzothiazepine derivative, on limb blood flow in anesthetized dogs: selective suppression of sympathetic nerve activity

TA-993, (-)-cis-3-acetoxy-5-(2-(dimethylamino)ethyl)-2, 3-di-hydro-8-methyl-2-(4-methylphenyl)-1,5-benzothiazepin-4(5H)one maleate, a new 1,5-benzothiazepine derivative with l-cis configuration, has a unique and selective increasing action on limb blood flow with little influence on arterial pressure besides an antiplatelet action. We studied the mechanism of increasing action of TA-993 on limb blood flow in anesthetized dogs. In a canine blood-perfused hindlimb preparation with a donor dog, TA-993 (100 microg/kg i.v.) did not increase femoral blood flow when administered to the donor dog, but did when administered to a recipient dog. TA-993 did not show the increasing action on femoral blood flow in the presence of hexamethonium or phentolamine, whereas it did in the presence of propranolol or atropine. TA-993 also showed a weak increasing effect on heart rate, which was inhibited by any one of these blockers. TA-993 (300 microg/kg i.v.) did not alter the phenylephrine (1-100 ng/kg i.a.)- or the talipexole (3-100 ng/kg i.a.)-induced increase in perfusion pressure in an autoperfused hindlimb. These results suggest that the increasing action of TA-993 on limb blood flow is mediated by the sympathetic nervous system but that the adrenergic receptors are not likely to be the central point of action of this new agent. There is a possibility that the mechanism of the increasing action on heart rate is different from that of its increasing action on limb blood flow.

Presence of molecular chaperones, heat shock cognate (Hsc) 70 and heat shock proteins (Hsp) 40, in the postsynaptic structures of rat brain

The synaptic localization of molecular chaperones, heat shock cognate protein 70 (Hsc70) and Hsp40, was investigated immunohistochemically in the normal rat brain. Postsynaptic density (PSD) fractions contained a constitutive form of HSP70, heat shock cognate protein 70 (Hsc70 or p73) but not inducible form of HSP70 (p72). The immunoreactivities of Hsc70 (p73) were distributed throughout the rat brain, in neuronal somata, dendrites and axons. Their immunoreactivity in neurons was localized in the cytoplasmic matrix, dendrites, and spines at the electron microscopic level. Presynaptic terminals, but less frequently than postsynaptic staining, were also reactive. Postsynaptic areas immediately beneath the synaptic contact or PSDs were immunoreactive for Hsc70. The Hsp40 was highly concentrated in PSD fractions. The staining of Hsp40 immunoreactivity was punctate and distributed widely in the brain. Hsp40 immunoreactivity was localized in dendritic spines, especially in the subsynaptic web, with weak staining of PSDs at the electron microscopic level. Double immunofluorescent staining and confocal microscopy revealed that Hsc70 and Hsp40 were co-localized on somata and neuronal processes of cultured cerebral neurons, on which synaptophysin immunoreactive spots were scattered. These results suggest that Hsp40 and Hsc70 are co-localized at postsynaptic sites and postsynaptic chaperone activity may be mediated by these two heat shock proteins.

Transcatheter embolization of celiac artery pseudoaneurysm following pancreatico-duodenectomy for pancreatic cancer. A case report

A case of transcatheter embolization of a celiac artery pseudoaneurysm in a 70-year-old man is reported. The pseudoaneurysm was considered to be the result of pancreatic anastomotic leakage and an intra-abdominal abscess following pancreaticoduodenectomy with irradiation of 66 Gy for pancreatic carcinoma. To avoid recanalization of the pseudoaneurysm due to retrograde blood flow, first all branches of the celiac artery were embolized with metallic coils, and then the celiac trunk was also occluded. Hepatic arterial flow was preserved by the right hepatic artery arising from the superior mesenteric artery. After the procedure, the patient had no noticeable complications associated with the embolization nor any recurrence of the pancreatic cancer, and he achieved a 2-year survival.

Detection of diaphragmatic defect as the cause of severe hepatic hydrothorax with magnetic resonance imaging

Severe right-sided hepatic hydrothorax occurred in an 83-yr-old Japanese woman with a 7-yr history of cryptogenic liver cirrhosis. Transdiaphragmatic communication was indirectly suggested by rapid migration of dye (indocyanine green) from the peritoneal to the pleural space. Magnetic resonance imaging studies also demonstrated a diaphragmatic defect as a characteristic hypointense jet flow across the diaphragm on both T1- and T2-weighted sagittal scans. Although no firm treatment for hepatic hydrothorax has been established and direct demonstration of diaphragmatic defect with noninvasive imaging is extremely rare, testing for diaphragmatic integrity is meaningful to provide a radical or less invasive treatment. Magnetic resonance imaging, as well as color Doppler ultrasonography, may be useful for the detection of diaphragmatic defects as the cause of hepatic hydrothorax.

Usefulness of extracorporeal membrane oxygenation for treatment of fulminant myocarditis and circulatory collapse

Prognosis for fulminant myocarditis with cardiogenic shock refractory to conventional therapy is poor. This report describes mechanical circulatory support with extracorporeal membrane oxygenation as an effective alternative for treating fulminant myocarditis with circulatory collapse.

Prognosis of patients with resection of stage IV gastric cancer

We retrospectively analyzed 116 patients who underwent resection of stage IV gastric cancer to investigate the prognostic factors responsible for long-term survival. Statistically significant clinicopathological differences between patients surviving 3 years or more (n = 9) and those surviving less than 3 years (n = 107) were observed in regard to macroscopic type, curability of surgery, lymph node metastasis and blood vessel invasion. These four variables also had a statistically significant influence on survival by univariate analysis. Multivariate analysis revealed that no residual tumor (R0) surgery was a significantly beneficial factor for long-term survival. However, no patients with the diffusely infiltrative type of tumor survived for more than 2 years even if they underwent R0 surgery. Patients without the diffusely infiltrative type who underwent R0 surgery had better survival rates: a 27.3% and 13.6%, 3 and 5 year survival rate, respectively. In conclusion, R0 surgery contributes to long-term survival even in stage IV gastric cancer, and some patients with the not diffusely infiltrative type, in particular, may receive a survival benefit by R0 surgery.

Resection of both hepatic and pulmonary metastases in patients with colorectal carcinoma

BACKGROUND

More than 40% of patients who undergo curative resection of advanced colorectal carcinoma can be expected to have recurrence of the disease. The most frequent sites of recurrence are the liver (33% of patients) and lung (22%). Interest has therefore focused on treating hepatic or pulmonary metastases, or both, to improve the outcomes of these patients. Although surgical resection has become an increasingly accepted treatment for resectable localized hepatic or localized pulmonary metastases from colorectal carcinoma, the value of aggressive surgery for the removal of both hepatic and pulmonary metastases from patients with primary colorectal carcinoma remains to be clarified.

METHODS

Data on 30 patients who had undergone resection of both hepatic and pulmonary metastases from colorectal carcinoma were included in the study.

RESULTS

Independent, significant prognostic features were found to be the time that hepatic or pulmonary metastases occurred and the distribution of pulmonary metastases. Median survival times were 30 months (range, 7-108 months) after resection of both hepatic and pulmonary metastases and 48.5 months (range, 11-149 months) after excision of the primary colorectal tumor. Actuarial 1-, 3-, and 5-year survival after resection of both hepatic and pulmonary metastases was 86.7%, 49.3%, and 43.8%, respectively. No perioperative mortality occurred. There were three cases of minor morbidity, which the authors considered acceptable.

CONCLUSIONS

Resection of both hepatic and pulmonary metastases from colorectal carcinoma may help to prolong the survival of a small group of patients with these metastases.

Resection of both hepatic and pulmonary metastases in patients with colorectal carcinoma

BACKGROUND

More than 40% of patients who undergo curative resection of advanced colorectal carcinoma can be expected to have recurrence of the disease. The most frequent sites of recurrence are the liver (33% of patients) and lung (22%). Interest has therefore focused on treating hepatic or pulmonary metastases, or both, to improve the outcomes of these patients. Although surgical resection has become an increasingly accepted treatment for resectable localized hepatic or localized pulmonary metastases from colorectal carcinoma, the value of aggressive surgery for the removal of both hepatic and pulmonary metastases from patients with primary colorectal carcinoma remains to be clarified.

METHODS

Data on 30 patients who had undergone resection of both hepatic and pulmonary metastases from colorectal carcinoma were included in the study.

RESULTS

Independent, significant prognostic features were found to be the time that hepatic or pulmonary metastases occurred and the distribution of pulmonary metastases. Median survival times were 30 months (range, 7-108 months) after resection of both hepatic and pulmonary metastases and 48.5 months (range, 11-149 months) after excision of the primary colorectal tumor. Actuarial 1-, 3-, and 5-year survival after resection of both hepatic and pulmonary metastases was 86.7%, 49.3%, and 43.8%, respectively. No perioperative mortality occurred. There were three cases of minor morbidity, which the authors considered acceptable.

CONCLUSIONS

Resection of both hepatic and pulmonary metastases from colorectal carcinoma may help to prolong the survival of a small group of patients with these metastases.

Conflict among individual mitochondrial proteins in resolving the phylogeny of eutherian orders

The phylogenetic relationship among primates, ferungulates (artiodactyls + cetaceans + perissodactyls + carnivores), and rodents was examined using proteins encoded by the H strand of mtDNA, with marsupials and monotremes as the outgroup. Trees estimated from individual proteins were compared in detail with the tree estimated from all 12 proteins (either concatenated or summing up log-likelihood scores for each gene). Although the overall evidence strongly suggests ((primates, ferungulates), rodents), the ND1 data clearly support another tree, ((primates, rodents), ferungulates). To clarify whether this contradiction is due to (1) a stochastic (sampling) error; (2) minor model-based errors (e.g., ignoring site rate variability), or (3) convergent and parallel evolution (specifically between either primates and rodents or ferungulates and the outgroup), the ND1 genes from many additional species of primates, rodents, other eutherian orders, and the outgroup (marsupials + monotremes) were sequenced. The phylogenetic analyses were extensive and aimed to eliminate the following artifacts as possible causes of the aberrant result: base composition biases, unequal site substitution rates, or the cumulative effects of both. Neither more sophisticated evolutionary analyses nor the addition of species changed the previous conclusion. That is, the statistical support for grouping rodents and primates to the exclusion of all other taxa fluctuates upward or downward in quite a tight range centered near 95% confidence. These results and a site-by-site examination of the sequences clearly suggest that convergent or parallel evolution has occurred in ND1 between primates and rodents and/or between ferungulates and the outgroup. While the primate/rodent grouping is strange, ND1 also throws some interesting light on the relationships of some eutherian orders, marsupials, and montremes. In these parts of the tree, ND1 shows no apparent tendency for unexplained convergences.

[Concomitant cardiac and pulmonary operation, the profits of not using cardio-pulmonary bypass]

We performed off pump CABG (coronary artery bypass grafting) and right upper lobectomy with R2a lymph nodes dissection on the patient suffered from both lung cancer in the right S1 and stenotic lesion in the left anterior descending artery. Because the coronary lesion was long-segmented one, it was not suitable for percutaneous transluminal coronary angioplasty. To perform absolutely curative operation for the lung cancer, CABG was undergone simultaneously under off pump condition. It is generally feared that the cardiovascular surgery under CPB may have adverse effect for the patient with malignant lesion. Off pump CABG is expected to avoid such disadvantage of CPB, and thought to be suitable method for such a patient as we present above.

Vascular endothelial growth factor in angiosarcoma

Angiosarcoma(AS) is a malignant tumour of the endothelium of lymphatic or blood vessels. Vascular endothelial growth factor (VEGF), a specific mitogen of endothelial cells, is considered essential for the growth of many tumours including AS. We have recently treated several patients with AS; in two of them, using a newly developed enzyme-linked immunosorbent assay (ELISA) for VEGF, we sequentially measured serum VEGF concentrations. While serial serum VEGF levels reflected tumour burden, the various VEGF concentrations were within the normal range we reported previously. Furthermore, the VEGF concentrations were not remarkably elevated in AS tumour tissue compared with benign vascular lesions and hypervascular tumours.

Pharmacological profile of T-0201, a highly potent and orally active endothelin receptor antagonist

The authors studied the pharmacological properties of N-(6-(2-(5-bromopyrimidin-4-yl)-4-(2-hydroxy-1, 1-dimethylethyl)benzensulfonamide sodium salt sesquihydrate (T-0201), a new nonpeptide endothelin (ET) receptor antagonist, in vitro and in vivo. In binding studies, T-0201 competitively antagonized the specific binding of [125I]-ET-1 to human cloned ETA receptors (the Ki value was 0.015 +/- 0.004 nM). T-0201 weakly inhibited [125I]-ET-1-binding to human cloned ETB receptors; the Ki value was 41 +/- 21 nM. T-0201 shifted the concentration-response curve of ET-1-induced contraction of the isolated rat aorta (ETA receptors) to the right (pA2 = 9.0 +/- 0.2). In the isolated rat trachea, a selective ETB agonist sarafotoxin S6c-induced contraction was inhibited by T-0201 (pA2 = 6.8 +/- 0.3). T-0201 also caused the inhibition of ET-1-induced contraction of the isolated rabbit pulmonary artery (pA2 = 5.7 +/- 0.3). In anesthetized rats, T-0201 (0.01-1 mg/kg) inhibited the pressor response to exogenous big ET-1 (1 nmol/kg i.v.), after both i.v. and p.o. administration, in a dose-dependent manner. The significant inhibitory effect of orally administered T-0201 on big ET-1-induced pressor response lasted for 4 hr at 0.1 mg/kg and for 8 hr at 1 mg/kg. Thus the present study demonstrates that T-0201 is a highly potent, long-lasting, orally active and selective ETA receptor antagonist.

[Postoperative follow-up of acute aortic dissection and the result of second operations]

Between January 1990 and March 1998, surgical treatment was performed in 75 patients with acute aortic dissection at Omiya Medical Center. Seventy-three patients (97%) of them were classified type A aortic dissection. Thirteen of them died due to hemorrhage (5 cases), cardiac failure (3 cases), visceral ischemia (3 cases) and others (2 cases) after the operation. Hospital mortality rate was 17.3%. Sixty-two survivors were followed up to 8 years. During the follow up period, five patients died due to pneumonia, gastric cancer, cardiac failure, brain hemorrhage and unknown event. Five-year survival rate including hospital death was 77% evaluated by Kaplan-Meier method. Second operations for the enlargement of residual false lumen with the entry were performed in 4 patients (6.5%) of 62 survivors. Second operations were also performed in other 6 patients referred to us from other hospitals because of the enlargement of false lumen. Nine of them survived (90%) and returned to their daily life.

Cloning of hamster preproendothelin-1 cDNA and its expression in the heart

To elucidate the pathophysiologic roles of endothelin-1 (ET-1) in the heart, we first cloned and sequenced a part of hamster preproET-1 cDNA from the heart of the CHF146 hamsters. The amino acid sequence has 89% homology to that of rat preproET-1 in the cloned part. The deduced hamster 21-residue mature ET-1 is identical to human, rat, canine, and mouse ET-1. In the next step we investigated the expression of preproET-1 mRNA in the failing heart of CHF146 hamsters. For this purpose, we used 46-week-old CHF146 hamsters and age-matched control healthy hamsters. Left ventricular (LV) + dP/dtmax was significantly lower in CHF146 hamsters than in control hamsters. LV end-diastolic pressure was significantly higher in CHF146 hamsters than in control hamsters, as was central venous pressure. These results suggested that the CHF146 hamsters developed congestive heart failure. The expression of preproET-1 mRNA was greatly enhanced in the LV of the CHF146 hamsters. Because it has been reported that ET-1 induces cardiac hypertrophy and injury to cardiac myocytes in addition to its potent positive inotropic and chronotropic actions, the present findings suggest that endogenous ET-1 plays pathophysiologic roles in the failing heart of CHF146 hamsters.

A combination of preductal aortic coarctation and type B dissection: report of a case

We present herein the case of a 39-year-old man found to have significant coarctation of the preductal aorta combined with a type B dissection, associated with Marfan's syndrome. This extremely rare pathological combination could be defined preoperatively only by a three-dimensional computed tomography scan. By means of selective cerebral perfusion, the coarctation was resected, and the total aortic arch was replaced with a Dacron graft.

Alpha1-adrenoceptor subtypes and two receptor systems in vascular tissues

The subtypes of alpha1-adrenoceptor are coexpressed in many tissues. We examined the relationship between coexpressed alpha1-adrenoceptor subtypes and their functions in blood vessels. Rat and rabbit aortas coexpressed three subtypes (alpha1A, alpha1B, alpha1D) and four subtypes (alpha1A, alpha1B, alpha1D, alpha1L), respectively. In rat aorta however, noradrenaline-induced contraction was mediated predominantly through the alpha1D subtype, and oxymetazoline produced alpha1B-mediated contraction. In rabbit aorta, concentration-response curves for noradrenaline were composed of two components (alpha1B and alpha1L-mediated), while oxymetazoline produced alpha1L-mediated contraction. Therefore, the inhibitory actions of some antagonists varied markedly among tissues and agonists. These results demonstrate diversity of the two receptor systems and suggest that the heterogeneity of physiological responses reflects the differences in functional subtypes among tissues and in their sensitivities to agonists and antagonists.