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DNA methylation functions as cellular memory beyond generations of cells and is involved in many biological processes. Because of its relatively stable nature compared with the transcriptome, the DNA methylation profile of cells can also be used to evaluate developmental similarity and cellular phenotypes. Recent insights into 5-hydroxymethylcytosine have started to reshape our view of the epigenetic regulation of mammalian development. Both global DNA methylation and hydroxymethylation levels change dynamically during preimplantation embryogenesis. It is known that DNA methylation plays an essential role in embryonic cell fate restriction, whereas its role in trophoblast development requires further research. Two distinct blastocyst-derived stem cell lines, embryonic stem (ES) cells and trophoblast stem (TS) cells, are used to study the epigenetic mechanisms underlying cell lineage maintenance and the regulation of cell differentiation. Such studies will allow us to understand the details of the epigenetic landscape of trophoblast development, which should offer valuable information for managing pregnancy-related diseases in humans.

The first cell differentiation in the mammalian development separates the trophoblast and embryonic cell lineages, resulting in the formation of the trophectoderm (TE) and inner cell mass (ICM) in blastocysts. Although a lower level of global DNA methylation in the genome of the TE compared with ICM has been suggested, the dynamics of the DNA methylation profile during TE/ICM differentiation has not been elucidated. To address this issue, first we identified tissue-dependent and differentially methylated regions (T-DMRs) between trophoblast stem (TS) and embryonic stem (ES) cells. Most of these TS-ES T-DMRs were also methylated differentially between trophoblast and embryonic tissues of embryonic day (E) 6.5 mouse embryos. Furthermore, we found that the human genomic regions homologous to mouse TS-ES T-DMRs were methylated differentially between human placental tissues and ES cells. Collectively, we defined them as cell-lineage-based T-DMRs between trophoblast and embryonic cell lineages (T-E T-DMRs). Then, we examined TE and ICM cells isolated from mouse E3.5 blastocysts. Interestingly, all T-DMRs examined, including the Elf5, Pou5f1 and Nanog loci, were in the nearly unmethylated status in both TE and ICM and exhibited no differences. The present results suggest that the establishment of DNA methylation profiles specific to each cell lineage follows the first morphological specification. Together with previous reports on asymmetry of histone modifications between TE and ICM, the results of the current study imply that histone modifications function as landmarks for setting up cell-lineage-specific differential DNA methylation profiles.

Oral squamous cell carcinomas (SCCs) are malignant tumours that frequently invade the mandibular bone and bone invasion is a common clinical problem. Recent studies have revealed that bone resorption by osteoclasts is an important step in the process of bone invasion by oral SCCs. However, the cellular and molecular mechanisms of bone invasion by oral SCCs remain unclear. Oral SCCs invade the mandibular bone through an erosive, mixed or infiltrative pattern that correlates with clinical behaviours. The expressions of interleukin (IL)-6, IL-11, tumour necrosis factor (TNF) α and parathyroid hormone-related protein (PTHrP) were higher in the infiltrative pattern than in the erosive pattern. These cytokines lead to receptor activator of NF-κB ligand (RANKL) expression or osteoprotegerin (OPG) suppression not only in oral SCC cells but also in cancer stromal cells to induce osteoclastogenesis. Taken together, oral SCCs provide a suitable microenvironment for osteoclastogenesis to regulate the balance of RANKL and OPG. In this review, we introduce recent advances in the knowledge of the cellular and molecular mechanisms, by which oral SCC invades mandibular bone based on the recent findings of our lab and others.

A tyrosine kinase inhibitor, genistein, caused the subcellular translocation of phosphoinositide-specific phospholipase C (PLC) activity from membrane fractions to cytosolic fractions in rat 3Y1 fibroblasts and their transformants by Rous sarcoma virus, SR-3Y1. The ratio of PLC activities associated with the membrane fractions to those of the homogenate fractions was greater in SR-3Y1 (32.6%) than in 3Y1 (20.8%) whereas membrane-associated PLC activities were strikingly reduced to the same levels in both cells by treatment with genistein. Moreover, it was found by immunoblotting analyses of membrane fractions that the amounts of PLC-gamma 1 isozyme were reduced to 20.4% of initial level in SR-3Y1 and to 30.2% of that in 3Y1 cells. While the levels of PLC-delta, another detectable PLC isozyme, were not altered by genistein suggesting that tyrosine kinase plays an important role in the association of PLC-gamma 1 with membranes. PLC-gamma 1 molecules were detected in anti-p60arc antibody immunoprecipitates of both 3Y1 and SR-3Y1 cells. The amounts of PLC-gamma 1 co-immunoprecipitating with src kinases were higher in SR-3Y1 than 3Y1 cells and were reduced in both cell types by treatment with genistein. In addition, it was confirmed that PLC-gamma 1 purified from rat liver was phosphorylated at a tyrosine residue and associated with viral src kinase and that src kinases associated with the recombinant SH2 region of PLC-gamma 1, expressed in Escherichia coli, depending upon phosphorylation of tyrosine residues. These findings suggest that both viral and cellular src kinases associate with PLC-gamma 1 and may mediate cellular signaling in normal and transformant cell growth.

An appropriate model was created by the paraperiosteal injection of mustard oil (20% allyl isothiocyanate dissolved in mineral oil) into the periarticular temporomandibular tissue of anaesthetized rats. Inflammation was assessed by the plasma extravasation of Evans' blue dye bound to plasma protein. This was confirmed visually and compared spectrophotometrically with the contralateral untreated control site (p less than 0.0005). A time-course study of the effect of mustard oil on Evans' blue extravasation revealed a gradually increasing effect that was maximal at 30 min after administration, with no further increase at 60 min. A dose-response study showed that giving 30 microliters of 20% mustard oil produced the maximal effect, with no further increase from 50 microliters. To confirm induction of inflammation, polymorphonuclear neutrophil infiltration was assessed morphometrically and found to increase in the treated tissue compared with the contralateral untreated control (p less than 0.001).

Serotoninergic neuron is concerned as an one of the pivotal factor of the tissue inflammation which lead to pain behavior. Sarpogrelate HCl is a novel compound which may modulate inflammatory reaction through 5-HT2A receptor antagonist. We show the involvement of the 5-HT2A receptor activity in the inflammatory and neuropathic pain. Systemic or local sarpogrelate administration provokes antinociceptive effect on 5-HT- or formalin-produced inflammatory pain behaviour in relation to spinal glutamate. Local sarpogrelate inhibits apoptosis and neuronal degeneration after chronic construction injury(CCI). These effects are reversed by 5-HT2A receptor agonist. These results suggests sarpogrelate has a beneficial effect on hyperalgesia and neuropathic pain via inhibiting 5-HT2A receptor.

Transcriptional repression of the transforming growth factor (TGF)-1P type II receptor (TPRII) gene appears to be a major mechanism to inactivate TGF-beta responsiveness in many human cancers. Because histone acetylation/deacetylation plays a role in transcriptional regulation, we have examined the effect of MS-275, a synthetic inhibitor of histone deacetylase, in human breast cancer cell lines. MS-275 showed antiproliferative activity against all human breast cancer cell lines examined and induced TbetaRII mRNA, but not TGF-beta type I receptor mRNA. MS-275 caused an accumulation of acetylated histones H3 and H4 in total cellular chromatin. An increase in the accumulation of acetylated histones H3 and H4 was detected in the TbetaRII promoter after treatment with MS-275. However, the level of histone acetylation did not change in chromatin associated with the TGF-beta type I receptor gene. MS-275 treatment enhanced TGF-beta1-induced plasminogen activator inhibitor 1 expression. Thus, antitumor activity of MS-275 may be mediated in part through the induction of TbetaRII expression and consequent potentiation of TGF-beta signaling.

We synthesized a novel anticancer agent MS-247 (2-[[N-[1-methyl-2-[5-[N-[4-[N,N-bis(2-chloroethyl) amino] phenyl]] carbamoyl]-1H-benzimidazol-2-yl] pyrrol-4-yl] carbamoyl] ethyldimethylsulfonium di-p-toluenesulfonate) that has a netropsin-like moiety and an alkylating residue in the structure. We evaluated antitumor activity of MS-247 using a human cancer cell line panel coupled with a drug sensitivity database and subsequently using human cancer xenografts. The average MS-247 concentration required for 50% growth inhibition against a panel of 39 cell lines was 0.71 microM. The COMPARE analysis revealed that the differential growth inhibition pattern of MS-247 significantly correlated with those of camptothecin analogues and anthracyclins, indicating that MS-247 and the two drug groups might have similar modes of action. MS-247 exhibited remarkable antitumor activity against various xenografts. A single i.v. injection of MS-247 significantly inhibited the growth of all 17 xenografts tested, which included lung, colon, stomach, breast, and ovarian cancers. In many cases, MS-247 was more efficacious than cisplatin, Adriamycin, 5-fluorouracil, cyclophosphamide, VP-16, and vincristine and was almost comparable with paclitaxel and CPT-11; these are the most clinically promising drugs at present. MS-247 was noticeably more effective than paclitaxel (in HCT-15) and CPT-11 (in A549, HBC-4, and SK-OV-3). The toxicity of MS-247, indicated by body weight loss, was reversible within 10 days after administration. The MS-247 mode of action showed DNA binding activity at the site where Hoechst 33342 bound, inhibited topoisomerases I and II (as expected by the COMPARE analysis) blocked the cell cycle at the G2-M phase, and induced apoptosis. These results indicate that MS-247 is a promising new anticancer drug candidate to be developed further toward clinical trials.

1. In rats, injection of mustard oil (MO) into the paw caused a gradual increase in flinching of the injected paw and this algogenic behavior corresponded with an increase in the CSF-Glu level. 2. The nerve growth factor (NGF) inducer, 4-methyl catechol (4MC), enhanced the frequency of flinching and this effect was dose dependent. In addition, spinal CSF-Glu release was significantly above baseline 10 min after MO injection. In contrast, morphine (MOR) pretreatment completely blocked this behavioral and neurohumoral effect. 3. Anti-NGF paw injection attenuated the algogenic behavior and spinal Glu release otherwise observed after 4MC treatment. 4. The results demonstrated that MO-induced hyperalgesia is associated with increased CSF-Glu release and that this effect is potentiated by a NGF inducer. These data also suggest a possible involvement of NGF in the development of central sensitization after acute peripheral nociceptive stimulation.

1. omega-CgTx attenuated formalin-evoked biphasic flinches, while PKC inhibitor (STU) attenuated phase 2 and was reversed by PDBu. 2. omega-CgTx and STU suppressed the increase in CSF-glutamate after formalin injection. 3. Morphine completely suppressed both increased flinching and CSF glutamate release. 4. Thus, omega-CgTx (N-type Ca channels) may regulate neurotransmitter release evoked by C fiber activation and the formalin-evoked hyperalgesia may possibly be provoked as a result of PKC activation elicited by both presynaptic neurotransmitter release and activation of NMDA receptors in the spinal neurons.

In rats, the jaw-opening reflex is elicited by activation of a nociceptive receptor by the electric stimulation of the tooth pulp. This study was undertaken to assess the effects of 30% nitrous oxide and 30% nitrous oxide with idazoxan, an alpha 2-adrenergic antagonist, on this reflex. Each rat received electric stimulation for the jaw-opening reflex at 3, 5, 7, 10, 15, and 20 min after both the start of inhalation and the withdrawal of 100% oxygen or 30% nitrous oxide in oxygen. Idazoxan, 400 micrograms/ kg, was administered intravenously at the start of the inhalation period. Amplitudes significantly decreased during inhalation of nitrous oxide, but they returned gradually to control levels after cessation of nitrous oxide inhalation. In the cases of 100% oxygen, 100% oxygen with idazoxan, and 30% nitrous oxide in oxygen with idazoxan, amplitudes did not change from controls during and after 30% nitrous oxide inhalation. The latency remained unchanged irrespective of the treatment. Since in rats the degree of inhibition by 30% nitrous oxide in oxygen is partially diminished by administration of idazoxan, we conclude that nitrous oxide affects an alpha 2-adrenergic receptor in the central nervous system.

The emergence of multidrug resistance(MDR) is a major problem in cancer chemotherapy. Many compounds are developed to reverse MDR, and some of them are under clinical trials. Among them, MS-209, a novel quinoline derivative, is one of the most potent MDR reversing agents. MS-209 at 3 microM effectively reverses MDR in various cell lines in vitro. MS-209 directly interacts with P-glycoprotein and inhibits the P-glycoprotein-mediated drug transport. Oral administration of MS-209 combined with anticancer drugs markedly increases the life span of mice bearing MDR tumor cells without causing serious side effects. Thus, MS-209 is an orally active and potent MDR reversing drug without serious side effects.

A novel quinoline compound, MS-209, was examined for its ability to reverse multidrug resistance (MDR) in several murine and human MDR solid tumor cell lines both in vitro and in vivo. MS-209 strongly reversed drug resistance to adriamycin (ADM) and vincristine (VCR) in acquired MDR tumor cell lines, 2780AD and KB-C1. In addition, MS-209 enhanced the cytotoxic effect of ADM and VCR on various human and murine cell lines. Particularly in 4-1St cells, which are extremely resistant to ADM and VCR, MS-209 at a concentration of 3 microM enhanced the cytotoxicity of ADM and VCR, 88- and 350-fold, respectively. MS-209 administered orally, together with ADM, enhanced the antitumor activity of ADM on Colon 26 and 4-1St tumors implanted subcutaneously (SC) in mice; the antitumor effect of ADM plus MS-209 was higher than that of ADM alone at the maximum tolerated dose (MTD). Furthermore, the coadministration schedules of MS-209 to attain the highest potentiation of ADM activity were examined using Colon 26 tumors. The maximum antitumor activity was obtained when MS-209 was administered on the same day as ADM. MS-209 administered a day before the ADM injection exhibited no potentiation effect, whereas MS-209 administered a day after the ADM injection showed a moderate effect. The effect of MS-209 was weaker when administered in a fractionated manner than when administered as a single dose. The results presented in this article suggest that MS-209 is an effective agent to overcome MDR in cancer chemotherapy.

Changes in pial vessel diameter combined with regional cerebral blood flow (CoBF) during infusion of vasodilating drugs, isosorbide dinitrate (ISDN) 5 micrograms/kg/min and nitroprusside (NTP) 5 micrograms/kg/min, compared with haemorrhagic hypotension were studied in cats anesthetized with halothane (1.0%). Pial arteries and veins were measured by image-splitting technique and were each divided into three groups according to the reference diameter: I;50 microns, II; 51microns100, III; 101microns. With either drug, the mean blood pressure (mBP) decreased by 10-20%. There was significant decrease in cerebral vascular resistance with ISDN compared with haemorrhagic hypotension while CoBF (H2 clearance) remained unchanged. Dilatation of pial arteries depending on vessel size with ISDN was two-hold compared with haemorrhagic hypotension without any change in all veins. Consistent and significant dilation of veins (I and II) was observed only during NTP infusion. These findings indicate the differential effect of ISDN and NTP on pial arteries and veins.

The effects of isosorbide dinitrate (ISDN) on regional cerebral blood flow (rCBF) and intracranial pressure (ICP) were examined in cats. A low dose of ISDN (2.5 micrograms/kg/min) infusion did not show any changes in cerebral hemodynamics. During high dose of ISDN (5.0 micrograms/kg/min) or NTP (5.0 micrograms/kg/min) infusion, mean blood pressure (mBP) decreased by 10 to 20% accompanied by decreased cerebral perfusion pressure (CPP: mBP-ICP), however, rCBF or ICP did not change. It is concluded that intravenous administrations of ISDN in a dose of 2.5-5.0 micrograms/kg/min that produce slight decrease in blood pressure did not influence on cerebral hemodynamics.

Two kinds of phosphoinositide-specific phospholipase C (PLC) were purified from rat liver by acid precipitation and several steps of column chromatography. About 50% of the activity could be precipitated when the pH of the liver homogenate was lowered to pH 4.7. The redissolved precipitate yielded two peaks, PLC I and PLC II, in an Affi-gel Blue column, and each was further purified to homogeneity by three sequential h.p.l.c. steps, which were different for the two enzymes. The purified PLC I and PLC II had estimated Mr values of 140,000 and 71,000 respectively on SDS/polyacrylamide-gel electrophoresis. Both enzymes hydrolysed phosphatidylinositol (PI), phosphatidylinositol 4-phosphate (PIP) and phosphatidylinositol 4,5-bisphosphate (PIP2) in a Ca2+- and pH-dependent manner. PLC I was most active at 10 microM- and 0.1 mM-Ca2+ for hydrolysis of PI and PIP2 respectively, whereas PLC II showed the highest activity at 5 mM- and 10 microM-Ca2+ for that of PI and PIP2 respectively. The optimal pH of the two enzymes also differed with substrates or Ca2+ concentration, in the range pH 5.0-6.0. Hydrolysis of phosphoinositides by these enzymes was completely inhibited by Hg2+ and was affected by other bivalent cations. From data obtained by peptide mapping and partial amino acid sequencing, it was clarified that PLC I and PLC II had distinct structures. Moreover, partial amino acid sequences of three proteolytic fragments of PLC I completely coincided with those of PLC-148 [Stahl, Ferenz, Kelleher, Kriz & Knopf (1988) Nature (London) 332, 269-272].

Two different forms of inositol phospholipid-specific phospholipase C (PLC) have been purified 2810- and 4010-fold, respectively, from a crude extract of rat brain. The purification procedures consisted of chromatography of both enzymes on Affi-Gel blue and cellulose phosphate, followed by three sequential high performance liquid chromatography steps, which were different for the two enzymes. The resultant preparations each contained homogeneous enzyme with a Mr of 85,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. One of these enzymes (PLC-II) was found to hydrolyze phosphatidyl-inositol 4,5-bisphosphate (PIP2) at a rate of 15.3 mumol/min/mg of protein and also phosphatidylinositol 4-monophosphate and phosphatidylinositol (PI) at slower rates. For hydrolysis of PI, this enzyme was activated by an acidic pH and a high concentration of Ca2+ and showed a Vmax value of 19.2 mumol/min/mg of protein. The other enzyme (PLC-III) catalyzed hydrolysis of PIP2 preferentially at a Vmax rate of 12.9 mumol/min/mg of protein and catalyzed that of phosphatidylinositol 4-monophosphate slightly. The rate of PIP2 hydrolysis by this enzyme exceeded that of PI under all conditions tested. Neither of these enzymes had any activity on phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, or phosphatidic acid. These two enzymes showed not only biochemical but also structural differences. Western blotting showed that antibodies directed against PLC-II did not react with PLC-III. Furthermore, the two enzymes gave different peptide maps after digestion with alpha-chymotrypsin or Staphylococcus aureus V8 protease. These results suggest that these two forms of PLC belong to different families of PLC.

cDNA clones coding for rat liver ribosomal proteins S17 and L30 have been isolated by positive hybridization-translation assay from a cDNA library prepared from 8-9S poly(A) + RNA from free polysomes of regenerating rat liver. The cDNA clone specific for S 17 protein (pRS 17-2) has a 466-bp insert with the poly(A) tail. The complete amino acid(aa) sequence of S 17 protein was deduced from the nucleotide sequence of the cDNA. S17 protein consists of 134 aa residues with an M r of 15377. The N-terminal aa sequence of S17 protein determined by automatic Edman degradation is consistent with the sequence data. The aa sequence of S17 shows strong homology (76.9%) to that of yeast ribosomal protein 51 [Teem and Rosbash, Proc. Natl. Acad. Sci. USA 80 (1983) 4403-4407] in the two-thirds N-terminal region. The cDNA clone specific for L30 protein (pRL30) has a 394-bp insert. The aa sequence of L30 protein was deduced from the nucleotide sequence of the cDNA. The protein consists of 114 aa residues with an M r of 12652. When compared with the N-terminal aa sequence of rat liver L30 protein [Wool, Annu. Rev. Biochem. 48 (1979) 719-754], pRL30 was found not to contain the initiation codon and 5'-noncoding region. The cDNA showed twelve silent changes in the coding region, one point mutation and one base deletion in the 3 ' -noncoding region, compared with mouse genomic DNA for L30 protein [Wiedemann and Perry, Mol. Cell Biol. 4 (1984) 2518-2528].

To investigate the pathogenesis and pathophysiology of dilated cardiomyopathy (DCM), we studied 28 patients with DCM by echocardiography and endomyocardial biopsy, and compared their findings with those of 34 patients including eight with myocarditis, seven with alcoholics, 12 with hypertensives and seven patients with hypertrophic cardiomyopathy. All 12 patients in the hypertensive group had congestive heart failure without accompanying high blood pressure, and prominent dilatation and uniform wall motion abnormality of the left ventricle observed echocardiographically on admission. After medical management, both heart failure and the echocardiographic abnormalities gradually resolved. Those in the alcoholic group had larger left ventricles and uniform wall motion abnormality compared to those in the other groups. The myocarditis and hypertrophic cardiomyopathy groups had smaller left ventricles, non-uniform wall motion and larger % myocardial fibrosis. Both ventricles in the hypertrophic cardiomyopathy group were thicker than those of the other three groups. Each patient with DCM had individual echocardiographic abnormalities, which could be categorized as two subsets depending on the degree of left ventricular dilatation and uniformity of the wall motion. The one was characterized by a prominently dilated left ventricle and uniform wall motion abnormality similar to the alcoholic group, and the other had less marked left ventricular dilatation and heterogeneous wall motion abnormality similar to the myocarditis group. From these findings, it was suggested that there are common factors to specific myocardial disease in the pathogenesis and pathophysiology of DCM, and thus, DCM might include many subsets of different etiologies.

To investigate the effect of long-term athletic training on the heart, pulsed Doppler echocardiography was performed in 117 male professional cyclists (Group C: 20-59 years of age), and 40 age- and sex-matched untrained normal controls (Group N). According to age, the subjects in each group were categorized in two subgroups: 74 cyclists (Group CI), 20-39 years of age and 43 cyclists (Group CII), 40-59 years of age; 24 control subjects (Group NI), 20-39 years of age and 16 control subjects (Group NII), 40-59 years of age. The average durations as professional cyclists were eight years in Group CI and 29 years in Group CII. The ratios of pre-ejection period to ejection time (LV-PEP/ET, RV-PEP/ET) as obtained from Doppler flow velocity patterns of the left and right ventricles (LV, RV) were used as parameters of systolic function. The peak flow velocities during rapid filling (LV-R, RV-R) and atrial systole (LV-A, RV-A), and the ratio of A to R (LV-A/R, RV-A/R) were used as parameters of diastolic filling dynamics. The parameters of systolic function of both ventricles and those of diastolic filling dynamics of the RV did not differ between Group C and Group N, Group CI and Group NI, and Group CII and Group NII. Study of the diastolic filling dynamics of the LV disclosed that Group C had a significantly higher LV-A/R (p less than 0.05) than did Group N; therefore, no significant differences between Group CI and Group NI, and Group CII had a significantly lower LV-R (p less than 0.005) and a higher LV-A/R (p less than 0.005) than did Group NII. Twenty-four hour ambulatory ECG monitoring was performed for 49 cyclists. Thirty cyclists aged 20-39 years were categorized in two groups according to their LV-A/R values: eight cyclists (Group A) with the LV-A/R greater than the mean + SD value (0.69) in Group NI and 22 cyclists (Group B) with the LV-A/R lower than or equal to 0.69. Nineteen cyclists aged 40-59 years were separated into two groups according to the LV-A/R value: 11 cyclists (Group A) with the LV-A/R values greater than the mean + SD value (0.89) in Group NII, and eight cyclists (Group B) with the LV-A/R equal to or less than 0.89.(ABSTRACT TRUNCATED AT 400 WORDS)

To investigate the relationship between regional contractile dynamics and regional myocardial lesions of the left ventricular wall in patients with hypertrophic cardiomyopathy (HCM), autopsy findings of 11 patients were compared with their ante mortem echocardiographic findings. The regional systolic wall thickenings (%RWT) of the interventricular septum (IVS) and left ventricular posterior wall (LVPW) obtained using M-mode echocardiography were converted into % normalized RWT (%NRWT) by the averaged %RWT in 15 normal subjects. The %NRWT was compared with the wall thickness obtained by echocardiography and/or autopsy, and histological findings, such as the myocardial fibrosis ratio, disarray area ratio, and mean myocyte diameter. 1. There were no significant correlations among wall thickness of the left ventricle, the myocardial fibrosis ratio, the disarray area ratio, and the mean myocyte diameter of each segment. 2. The %NRWT in 22 segments of the 11 patients with HCM was not significantly related to the echocardiographic wall thickness at end-systole, the autopsy wall thickness, the mean myocyte diameter and the disarray area ratio, but that correlated significantly with the echocardiographically-determined wall thickness at end-diastole (r = -0.53, p less than 0.02), and with the myocardial fibrosis ratios (r = -0.59, p less than 0.005). 3. The %NRWT in the IVS was significantly less than that in the LVPW. The %NRWT in all segments of the LVPW was significantly related to the myocardial fibrosis ratios (r = -0.80, p less than 0.005), but was not related to the wall thicknesses or the disarray area ratios.(ABSTRACT TRUNCATED AT 250 WORDS)

Although the prognosis of dilated cardiomyopathy (DCM) is poor, some patients occasionally follow favorable clinical courses and have significant improvement in cardiac function. To elucidate the mechanism of such improvement, we compared the clinical and pathological findings of 54 cases with DCM, including 12 cases with significant improvement (Dd less than 55 mm, %FS greater than 22%) during two years' follow-up (improved group), 26 without significant improvement (unimproved group), and 16 who died within two years (decreased group). Percent fractional shortening (%FS) in the deceased group was less than that in the unimproved group (12.4 +/- 3.9 vs 17.2 +/- 6.2, p less than 0.01). Pulmonary capillary pressure (PC) and % fibrosis in the deceased group were greater than those in the unimproved group [(22.7 +/- 9.5 vs 11.4 +/- 4.2 mmHg, p less than 0.001), (21.7 +/- 9.9 vs 13.4 +/- 3.6, p less than 0.01)], respectively. Although Dd, Ds, %FS, end-diastolic wall thickness (Thd), and PC in the improved group were not different from those in the unimproved group. End-systolic wall stress (WSes) in the improved group was greater than that in the unimproved group (376 +/- 73 vs 319 +/- 60 g/cm2, p less than 0.02), but % fibrosis was less in the improved group (7.6 +/- 3.4 vs 13.4 +/- 3.6, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

To diagnose latent dilated cardiomyopathy (latent DCM), we performed loading echocardiography with Angiotensin II and ergometer exercise in 41 patients. Twenty-one patients were suspected of having latent DCM because of histories, of heart failure of myocarditis; 10 patients had DCM; and 10 normal persons served as controls. On angiotensin II loading, cardiac function deteriorated in the DCM group, but it was maintained in the normal controls. Nine patients in the latent DCM group showed the same pattern as normals (L1-group), and 12 did as the DCM group (L2-group). Although % fractional shortening, end-diastolic and end-systolic dimensions of the left ventricle did not differ between the L1 and L2-groups, the A/R, the ratio of the pulsed Doppler echocardiogram at the left ventricular inflow tract, was larger and the exercise change of the % fractional shortening and exercise tolerance were less in the L2-group than in the L1-group. Furthermore, the biopsy findings of the L2-group were similar to those of the DCM group in terms of myocardial degeneration, myocardial hypertrophy and interstitial fibrosis. Thus, patients in the L2-group were thought to have a risk for DCM, and were cases of latent DCM. Angiotensin II loading is thought to be useful for diagnosing such cases.

Twenty-one members of a family were traced for three generations including the propositus, who had typical dilated cardiomyopathy (DCM)-like features. Clinical, radiological, electrocardiographic and echocardiographic examinations were performed for 13 of 16 still living. Five of 21 members died including three of sudden death. Among living 16 members, five had congestive heart failure, greater than grade III of the NYHA, and cardiomegaly on chest radiography in five. Left ventricular hypertrophy, abnormal Q waves, and ST-T changes were observed on electrocardiography in two, five and eight members, respectively. Echocardiography revealed asymmetric septal hypertrophy (ASH) in four, two of whom had systolic anterior motion (SAM) of the mitral valve. Two had features simulating DCM, and five had mitral valve prolapse. Among six patients with ASH or features simulating DCM, four had cardiac catheterization, coronary angiography and endomyocardial biopsy. None had significant coronary stenosis, but all had high left ventricular end-diastolic pressure (LVEDP) (23 +/- 7 mmHg). Endomyocardial biopsy showed moderate myocardial cellular hypertrophy, interstitial myocardial fibrosis, nuclear changes and myocardial disarrangement, with features characteristic of HCM. In this family with malignant HCM, patients had various clinical features including typical HCM, simulated DCM, DCM coexisted with mitral valve prolapse, and sudden death occurred frequently.

A two and a half year follow-up study of segmental left ventricular wall motion was performed by two-dimensional echocardiography for 26 patients with dilated cardiomyopathy (DCM). Segmental analysis of left ventricular wall motion abnormalities (WMA) was performed using 11 segments obtained by short- and long-axis views of the left ventricle. Wall motion in each segment was classified and assigned a numerical score as normal (0), hypokinetic (1), severely hypokinetic (2), and akinetic or dyskinetic (3). Based on this categorization, a wall motion abnormality index (WMAI) was derived as an overall assessment of left ventricular asynergy. The intersegmental standard deviation of the wall motion abnormality score was used as an index of left ventricular asynergy (non-uniformity index: NUI). During the follow-up period, the wall motion abnormality index increased in all of the 26 patients (from 1.23 to 1.82, p less than 0.001), but the non-uniformity index did not change (from 0.72 to 0.73). When comparing the non-uniformity index among three groups classified according to the grade of wall motion abnormality, both at the initial and during follow-up studies, the moderate wall motion abnormality group (1.0 less than or equal to WMAI less than 2.0) had larger non-uniformity indexes (0.83, 0.84) than the other groups, and the severe non-uniformity index (greater than or equal to 0.9) was observed solely in the moderate group. In the follow-up study, these 26 patients were categorized in two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

The relationship between left ventricular thrombus and left ventricular dynamics in dilated cardiomyopathy (DCM) was studied by echocardiography and postmortem examination. The subjects were 57 patients with DCM, 40 were survival patients examined by echocardiography and 17 were autopsy patients. Systemic or pulmonary embolism occurred in 10 of 57 patients, 4 of 40 survival patients and 6 of 17 autopsy patients. Intracardiac thrombus was detected in 11 of 40 survival patients and was found in 8 of 17 autopsy patients. Left ventricular segmental wall motion abnormalities were observed in all 40 patients examined by two-dimensional echocardiography and apical dyskinesis or akinesis was observed more frequently in patients with left ventricular thrombus than in patients without left ventricular thrombus. Of 33 patients examined by pulsed Doppler echocardiography, Doppler ejection flow signals in the apical long axis view were recorded in 9% at the apex, in 17% at the middle portion and in 57% at the portion near the interventricular septal center. The signals at the portion near the interventricular septal center were recorded in only 2 patients with left ventricular thrombus but in 66% of patients without left ventricular thrombus. Systemic or pulmonary embolism and intracardiac thrombus occurred less frequently in patients treated with warfarin than in patients without warfarin. These results indicate that endomyocardial and blood flow disorders of the left ventricle play important roles in the occurrence of left ventricular thrombus and that anticoagulant therapy is useful for the prevention of systemic or pulmonary embolism and cardiac thrombus.

A cDNA clone specific for rat ribosomal protein S26 was isolated by a positive hybridization translation assay from a cDNA library made for 8-9S poly(A)mRNA from regenerating rat liver. The nucleotide sequence of the cDNA was determined. The sequence contains 23 base pairs in the 5' noncoding region, 345 base pairs in the protein coding region and 67 base pairs in the 3' noncoding region besides the poly(A) tail. The primary structure of the protein S26 was deduced from the nucleotide sequence. It consists of 115 amino acids. Its molecular weight is 13,015 and its pI is about 11.1. The calculated amino acid composition is consistent with the reported composition of S26. From the results of Southern blot analysis, the protein S26 appears to have multiple genes.

A fourth type of rat phosphoinositide-specific phospholipase C (PLC IV) has been cloned for cDNA and sequenced. PLC IV is distinct from the other three types of rat PLC (PLC I, II, and III) with respect to primary structure and tissue distribution of its mRNAs. PLC IV contains two homologous regions included commonly in PLC I, II, and III and is most similar to PLC II (identity: 50.2%). PLC IV, in common with PLC II, has a sequence homologous to the N-terminal regulatory domains of nonreceptor tyrosine kinases of the src-family of oncogenes. Using an Escherichia coli expression system, we succeeded in producing active PLC IV in E. coli crude extracts. Various truncation experiments of the PLC IV cDNA revealed that the src-related domain is not necessary for catalytic activity while both domains homologous among PLC I-IV are essential. PLC IV is expressed in various rat tissues and abundant in spleen, suggesting that PLC IV plays a fundamental role in cellular functions such as growth and secretion.