Nonlinear Pattern Analysis of Ventricular Premature Beats by Mutual Information

The frequency of ventricular premature beats (VPBs) has been related to the risk of mortality. However, little is known about the temporal pattern of occurrence of VPBs and its relationship to autonomic activity. Hence, we applied a general correlation measure, mutual information, to quantify how VPBs are generated over time. We also used mutual information to determine the correlation between VPB production and heart rate in order to evaluate effects of autonomic activity on VPB production. We examined twenty subjects with more than 3000 VPBs/day and simulated ran-( dom time series of VPB occurrence. We found that mutual information values could be used to characterize quantitatively the temporal patterns of VPB generation. Our data suggest that VPB production is not random and VPBs generated with a higher value of mutual information may be more greatly affected by autonomic activity.

90-Day repeated-dose toxicity study of licorice flavonoid oil (LFO) in rats

Licorice flavonoid oil (LFO) is a new functional food ingredient consisting of licorice hydrophobic polyphenols in medium-chain triglycerides (MCT). As part of a safety evaluation, a 90-day oral toxicity study in rats was conducted using an LFO concentrate solution (2.90% glabridin). Male and female animals were assigned to one of 12 groups (10 males or females per group) and received corn oil (negative control), MCT (vehicle control), or 400, 600, 800 or 1600 mg/kg of the LFO concentrate solution. In conclusion, LFO concentrate solution induced an anticoagulation effect in both sexes, although there was a clear sex difference. Based on these findings, it is concluded that the no-observed-adverse-effect level (NOAEL) for the LFO concentrate solution is estimated to be 800 mg/kg/day for female rats, and approximately 400 mg/kg/day for male rats.

[Successful administration of nifekalant hydrochloride for postoperative junctional ectopic tachycardia in congenital cardiac surgery]

Two episode of junctional ectopic tachycardia (JET) caused hemodynamic deterioration early after tetralogy of Fallot repair in an 8-month-old infant. Sinus rhythm resumed in each of the episodes immediately after intravenous administration of nifekalant hydrochloride (NIF), a newly developed Vaughan-Williams class III antiarrhythmic drug in Japan. Although QT interval was modestly prolonged with NIF, no life-threatening ventricular arrhythmia (i.e., torsades de pointes) occurred. NIF might be an effective alternative in the treatment of postoperative JET in congenital cardiac surgery.

Octaarginine-modified multifunctional envelope-type nanoparticles for gene delivery

This study describes a multifunctional envelope-type nano device (MEND) that mimics an envelope-type virus based on a novel packaging strategy. MEND particles contain a DNA core packaged into a lipid envelope modified with an octaarginine peptide. The peptide mediates internalization via macropinocytosis, which avoids lysosomal degradation. MEND-mediated transfection of a luciferase expression plasmid achieved comparable efficiency to adenovirus-mediated transfection, with lower associated cytotoxicity. Furthermore, topical application of MEND particles containing constitutively active bone morphogenetic protein (BMP) type IA receptor (caBmpr1a) gene had a significant impact on hair growth in vivo. These data demonstrate that MEND is a promising non-viral gene delivery system that may provide superior results to existing non-viral gene delivery technologies.

Ultrafast photoinduced melting of a spin-Peierls phase in an organic charge-transfer compound, K-tetracyanoquinodimethane

Ultrafast photoinduced phase transition in a spin-Peierls (SP) system of K-tetracyanoquinodimethane (K-TCNQ) was studied by femtosecond (fs) reflection spectroscopy. Photocarriers destabilize the SP phase, resulting in a decrease in molecular dimerization within 400 fs. Such a melting of the SP phase drives three kinds of coherent oscillations. By comparing the oscillations with the Raman bands activated by the dimerization, we show that the oscillation of 20 cm-1 is due to an LO phonon, and it plays an important role for the stabilization of the SP phase.

Direct observation of excitons and a continuum of one-dimensional Mott insulators: a reflection-type third-harmonic-generation study of Ni-halogen chain compounds

The third-harmonic-generation (THG) spectrum was measured for a NiBr-chain compound, which is a one-dimensional Mott insulator, in a reflection configuration. A sharp peak and a shoulder structure in the THG spectrum are attributed to three-photon resonance to an exciton and a continuum, respectively. The band-edge energy, the exciton binding energy, and the spectral weights for the exciton and the continuum were determined from comparative studies of linear absorption, THG, and electroreflectance spectra. The excitonic effect is more pronounced in the NiCl chain than in the NiBr chain.

Large optical nonlinearity of semiconducting single-walled carbon nanotubes under resonant excitations

We measured third-order nonlinear susceptibility (chi(3)) spectra in semiconducting single-walled carbon nanotubes (SWNTs) by the Z-scan method. |Imchi(3)| is remarkably enhanced under resonant excitation to the lowest interband transition, reaching 4.2 x 10(-6) esu and 1.5 x 10(-7) esu in SWNTs grown by the laser ablation and HiPco methods, respectively. A comparison of the transient absorption changes evaluated by degenerate and nondegenerate pump-probe measurements suggests that the resonant enhancement of |Imchi(3)| is dominated by a coherent process rather than by saturation of absorption.

Existence of a Threshold for Induction of Aberrant Crypt Foci in the Rat Colon with Low Doses of 2-Amino-1-methyl-6-phenolimidazo[4,5-b]pyridine

Until recently it has been generally considered that genotoxic carcinogens have no threshold in exerting their potential for cancer induction. However, the nonthreshold theory can be challenged with regard to assessment of cancer risk to humans. In the present study we show that a food derived, genotoxic hepatocarcinogen, 2-amino-1-methyl-6-phenolimidazo[4,5-b]pyridine (PhIP), does not induce aberrant crypt foci (ACF) as preneoplastic lesions at low dose (below 50 ppm) or 8-hydroxy-2'-deoxyguanosine (below 400 ppm) in the rat colon. Moreover PhIP-DNA adducts were not formed at the lowest dose (below 0.01 ppm). Thus, the dose required to initiate ACF is approximately 5000 times higher than that needed for adduct formation. The results imply a no-observed effect level (existence of a threshold) for colon carcinogenesis by a genotoxic carcinogen.

[Lung metastasis with a 12 years disease free interval from the first surgery of synovial sarcoma; report of a case]

A 48-year-old woman was admitted for surgery on a lung tumor found incidentally. Her medical history showed a synovial sarcoma of left inguinal region which was resected 12 years ago. We performed segmentectomy of left S4 + 5 to removed the metastatic tumor. Histological examination revealed that the tumor was metastatic synovial sarcoma. Synovial sarcoma can metastasize to lung frequently but such a long disease free interval as 12 years is quite uncommon.

Ultrafast optical switching to a metallic state by photoinduced mott transition in a halogen-bridged nickel-chain compound

We demonstrate the ultrafast photoinduced Mott transition from a charge transfer insulator to a metal in a halogen-bridged Ni-chain compound by pump-probe reflection spectroscopy. Upon the irradiation of a 130-femtosecond laser pulse, the spectral weight of the gap transition is transferred to the inner-gap region. When the photoexcitation density exceeds 0.1/Ni site, the Drude-like high-reflection band appears in the infrared region, signaling the formation of a metallic state. The photogeneration of the metallic state and the subsequent recovery to the original gapped state occur within a few picoseconds.

Sast124, a novel splice variant of syntrophin-associated serine/threonine kinase (SAST), is specifically localized in the restricted brain regions

Syntrophin is an adaptor protein that binds signaling molecules to the dystrophin-associated protein complex, which connects extracellular matrix to intracellular cytoskeleton for construction and maintenance of the postsynaptic structures in the neuromuscular junction and the CNS. Among these signaling molecules, a family of microtubule-associated serine/threonine kinases has a unique structural feature with a serine/threonine kinase domain and a postsynaptic density protein-95/discs large/zona occludens-1 domain. In the present study, we identified syntrophin-associated serine/threonine kinase-124, a novel splice variant of the syntrophin-associated serine/threonine kinase which is a member of the microtubule-associated serine/threonine kinases family. Comparing to the original clone (syntrophin-associated serine/threonine kinase-170), syntrophin-associated serine/threonine kinase-124 is truncated just downstream of the postsynaptic density protein-95/discs large/zona occludens-1 domain. Using a monoclonal antibody specifically recognizing syntrophin-associated serine/threonine kinase-124, strong expression of the protein was observed in neurons of the subventricular zone and granule cells of the olfactory bulb, Islands of Calleja, hippocampal dentate gyrus and cerebellum. syntrophin-associated serine/threonine kinase-124 is selectively localized in the nuclei of neurons and distinct from syntrophin-associated serine/threonine kinase-170, which is interacting with syntrophin on the cell surface. Considering the tissue and subcellular distributions of syntrophin-associated serine/threonine kinase-124, it is suggested that syntrophin-associated serine/threonine kinase-124 may have functions in transcriptional regulation for the features commonly shared by these neurons. On the other hand, syntrophin-associated serine/threonine kinase-124 was also localized in glia-like cell bodies in the corpus callosum and fiber bundles in the spinal trigeminal and solitary tracts, suggesting syntrophin-associated serine/threonine kinase-124 may have other functions in these types of cells.

Novel optical and magnetic bistability and photoinduced transition in a one-dimensional halogen-bridged binuclear pt complex

In iodine-bridged binuclear Pt compounds, R(4)[Pt(2)(pop)(4)I]nH(2)O and R(')(2)[Pt(2)(pop)(4)I]nH(2)O (pop=P(2)O5H2-2), electronic structures on the PtPtI chains have been controlled between a diamagnetic charge-density-wave (CDW) state and a paramagnetic charge-polarization (CP) state by modification of the counterions (R, R') located between chains. In the R=(C2H5)2NH+2 compound, a pressure-induced CP to CDW transition with a drastic color change is identified. This transition is accompanied by a large hysteresis loop within which photoinduced transition between CDW and CP can be driven by selecting the excitation photon energy.

Tuning of electronic structures of quasi-one-dimensional bromo-bridged Ni(III) complexes with strong electron-correlation by doping of Co(III) ions, [Ni(1-x)Co(x)(Chxn)(2)Br]Br(2)

We have succeeded in synthesizing the Ni(III) complexes doped by Co(III) ions, [Ni(1-x)Co(x)(chxn)(2)Br]Br(2) (x = 0, 0.043, 0.093, and 0.118) by using an electrochemical oxidation method. The single-crystal reflectance spectrum of x = 0.118 shows an intense CT band about 0.5 eV, which is lower than that of [Ni(chxn)(2)Br]Br(2) (1.3 eV). The single-crystal electrical conductivities at room temperature of these compounds increase with increase of the amounts of doping of Co(III) ions. In the ESR spectra, peak-to-peak line widths DeltaH(pp) at room temperature change about 600 G in [Ni(chxn)(2)Br]Br(2) to 200 G in x = 0.118. Such a large x dependence of DeltaH(pp) seems to be ascribed to the increasing contribution from the increasing Curie spins which have smaller line width. Therefore, we have tuned the electronic structures of quasi-one-dimensional bromo-bridged Ni(III) complexes with strong electron correlations by doping of Co(III) ions.

Lack of antagonism between nicorandil and sulfonylurea in stable angina pectoris

The aim of this study was to clarify whether or not nicorandil (a potassium channel opener) caused adverse reactions in patients with angina pectoris who also had diabetes mellitus treated with sulfonylurea (a potassium channel inhibitor). Nineteen diabetic patients with angina pectoris were enrolled, eight were treated with glibenclamide (group A) and 11 were not (group B). Treadmill exercise testing and frequency of anginal attacks were used to evaluate the severity of angina pectoris. Blood sugar and hemoglobin A1c were measured for evaluation of diabetes mellitus control. Exercise tolerance, frequency of anginal attacks and diabetes mellitus control were not perturbed by treatment in either group. In conclusion, there were no antagonistic reactions from the combination of nicorandil with sulfonylurea in angina pectoris complicated by diabetes mellitus.

Ultrafast optical switching from an ionic to a neutral state in tetrathiafulvalene-p-chloranil (TTF-CA) observed in femtosecond reflection spectroscopy

Ultrafast optical switching from an ionic ( I) to a neutral ( N) state in TTF-CA was observed in femtosecond reflection spectroscopy. Charge transfer excitation in the I phase produces N donor ( D0) acceptor ( A0) strings within 2 ps. These initial N states decay with a lifetime of 300 ps at 4 K, but rather multiply leading to macroscopic I-N conversion within 20 ps at 77 K just below the N-I transition temperature T(NI). Near T(NI), we also found the evidence for the coherent motion of the macroscopic N-I domain boundary with a period of 85 ps.

The copper-chelating agent, trientine, suppresses tumor development and angiogenesis in the murine hepatocellular carcinoma cells

Angiogenesis is now recognized as a crucial process in tumor development, including hepatocellular carcinoma (HCC). Since HCC is known as a hypervascular tumor, anti-angiogenesis is a promising approach to inhibit the HCC development. Trientine dihydrochloride (trientine) is used in clinical practice as an alternative copper (Cu)-chelating agent for patients with Wilson's disease of penicillamine intolerance. In our study, we examined the effect of Cu-chelating agents on tumor development and angiogenesis in the murine HCC xenograft model. Although both trientine and penicillamine in the drinking water suppressed the tumor development, trientine exerted a more potent inhibitory effect than penicillamine. In combination with a Cu-deficient diet, both trientine and penicillamine almost abolished the HCC development. Trientine treatment resulted in a marked suppression of neovascularization and increase of apoptosis in the tumor, whereas tumor cell proliferation itself was not altered. In vitro studies also exhibited that trientine is not cytotoxic for the tumor cells. On the other hand, it significantly suppressed the endothelial cell proliferation. These results suggested that Cu plays a pivotal role in tumor development and angiogenesis in the murine HCC cells, and Cu-chelators, especially trientine, could inhibit angiogenesis and enhance apoptosis in the tumor with consequent suppression of the tumor growth in vivo. Since trientine is already used in clinical practice without any serious side effects as compared to penicillamine, it may be an effective new strategy for future HCC therapy.

Metallic behavior and periodical valence ordering in a MMX chain compound, Pt(2)(EtCS(2))(4)I

A new one-dimensional (1-D) halogen-bridged mixed-valence diplatinum(II,III) compound, Pt(2)(EtCS(2))(4)I (3), has been successfully synthesized from [Pt(2)(EtCS(2))(4)] (1) and [Pt(2)(EtCS(2))(4)I(2)] (2). These three compounds have been examined using UV-visible-near-IR, IR, polarized Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and X-ray crystal structure analyses (except for 1). Compound 3 was further characterized through electrical transport measurements, determination of the temperature dependence of lattice parameters, X-ray diffuse scattering, and SQUID magnetometry. 3 crystallizes in the monoclinic space group C2/c and exhibits a crystal structure consisting of neutral 1-D chains with a repeating -Pt-Pt-I- unit lying on the crystallographic 2-fold axis parallel to the b axis. The Pt-Pt distance at 293 K is 2.684 (1) A in the dinuclear unit, while the Pt-I distances are essentially equal (2.982 (1) and 2.978 (1) A). 3 shows relatively high electrical conductivity (5-30 S cm(-1)) at room temperature and undergoes a metal-semiconductor transition at T(M-S) = 205 K. The XPS spectrum in the metallic state reveals a Pt(2+) and Pt(3+) mixed-valence state on the time scale of XPS spectroscopy ( approximately 10(-17) s). In accordance with the metal-semiconductor transition, anomalies are observed in the temperature dependence of the crystal structure, lattice parameters, X-ray diffuse scattering, and polarized Raman spectra near T(M-S). In variable-temperature crystal structure analyses, a sudden and drastic increase in the Pt-I distance near the transition temperature is observed. Furthermore, a steep increase in U(22) of iodine atoms in the 1-D chain direction has been observed. The lattice parameters exhibit significant temperature dependence with drastic change in slope at about 205-240 K. This was especially evident in the unit cell parameter b (1-D chain direction) as it was found to lengthen rapidly with increasing temperature. X-ray diffraction photographs taken utilizing the fixed-film and fixed-crystal method for the metallic state revealed the presence of diffuse scattering with line shapes parallel to the a* axis indexed as (-, n + 0.5, l) (n; integer). Diffuse scattering with k = n + 0.5 is considered to originate from the 2-fold periodical ordering corresponding to -Pt(2+)-Pt(2+)-I-Pt(3+)-Pt(3+)-I- or -Pt(2+)-Pt(3+)-I-Pt(3+)-Pt(2+)-I- in an extremely short time scale. Diffuse lines corresponding to 2-D ordering progressively decrease in intensity below 252 K and are converted to the diffuse planes corresponding to 1-D ordering near T(M-S). Furthermore, diffuse planes condensed into superlattice reflections below T(M-S). Polarized Raman spectra show temperature dependence through a drastic low-energy shift of the Pt-I stretching mode and also through broadening of bands above T(M-S).

Large third-order optical nonlinearity of Cu-O chains investigated by third-harmonic generation spectroscopy

Spectra of the third-order nonlinear susceptibility chi((3)) have been investigated for one-dimensional Mott insulators, Sr(2)CuO(3) and Ca(2)CuO(3), by applying the third-harmonic generation (THG) spectroscopy on their single-crystalline thin films. The three-photon resonance to the lowest charge-transfer (CT) state with odd parity strongly enhances chi((3)), which is of the order of 10(-9) esu. The two-photon resonant structure unravels the even-CT state, located close to the odd-CT state. Two types of chi((3)) spectra obtained from THG and the electroreflectance measurements are explained based on the concept of spin-charge separation.

[Assessment of left ventricular function with the solid-state digirad 2020tc Imager]

Multigated equilibrium radionuclide ventriculography from best septal position (LAO view) was performed in 17 patients with cardiac disease with a single detector Anger-type gamma camera (GCA 602A, Toshiba), then immediately imaged with a solid-state, multi-crystal gamma camera (Digirad 2020tc Imager). Acquisition times were the same of 10 minutes. The solid-state gamma camera uses CsI(Tl) as the scintillation material and a Si photodiode. CsI(Tl) has a higher density and higher atomic number than NaI(Tl), so that its efficiency for detecting gamma rays is higher. To confirm this, total acquisition counts in 17 patients obtained from the 2020tc Imager were significantly higher than those obtained from the Anger-type camera (7847 +/- 2061 K vs. 4427 +/- 1162 K counts, p < 0.0001). In comparing left ventricular ejection fractions obtained from the Anger-type camera and the 2020tc Imager data, an excellent correlation was revealed with a correlation coefficient of 0.97 (p < 0.0001). Again, peak ejection rate and peak filling rate obtained from the 2020tc Imager data correlated well with those obtained from the Anger-type camera data (r = 0.93, p < 0.0001 and r = 0.80, p < 0.001, respectively). These data reveal that the 2020tc Imager has an excellent data collection efficiency and a high reliability in assessment of left ventricular function. Thus, the solid-state gamma camera was thought to be a useful hardware in nuclear cardiology.

Resting Ultrasonic Tissue Characterization and Dobutamine Stress Echocardiography for Prediction of Functional Recovery in Chronic Left Ventricular Ischemic Dysfunction

This study was designed to assess the diagnostic accuracy of the percentage of resting systolic wall thickening (WT), dobutamine stress echocardiography (DSE), resting cyclic variation of integrated backscatter (IBS-CV), and low-dose dobutamine stress IBS-CV (DSE-IB) for the prediction of regional function recovery (RFR) in patients with chronic left ventricular (LV) ischemic dysfunction. The study also evaluated whether or not global LV function affected the diagnostic accuracy. All studies were conducted before percutaneous transluminal coronary angioplasty (PTCA) and RFR was assessed after PTCA (mean interval, 10 months) in 30 patients with chronic LV ischemic dysfunction. Patients were divided into 2 groups according to the LV ejection fraction (LVEF): group A, LVEF<40%, n=14; group B, LVEF> or =40%, n=16. Of a total of 480 segments, 37 initially demonstrating akinetic wall motion before PTCA were analyzed. The wall motion of 24 of the 37 segments improved on visual analysis after PTCA. In the prediction of RFR, resting WT, DSE, resting IBS-CV and DSE-IB had sensitivities of 79%, 79%, 92% and 62%, and specificities of 54%, 84%, 83% and 69%, respectively. In particular, the resting IBS-CV in group A, as well as DSE, was an excellent predictor of RFR (sensitivity, 100%; specificity, 86%; vs sensitivity, 82%; specificity, 78%; respectively). Therefore, both resting IBS-CV and DSE are useful predictors for RFR in patients with chronic LV ischemic dysfunction.

Simultaneous assessment of Tc-99m-sestamibi and I-123-BMIPP myocardial distribution in patients with myocardial infarction: evaluation of left ventricular function with ECG-gated myocardial SPECT

123I-labeled 15-(p-iodophenyl)-3R,S-methyl pentadecanoic acid (BMIPP) is a branched-chain free fatty acid that is used to evaluate various cardiac diseases. The aim of the present study was to investigate the relationship between myocardial perfusion (99mTc-sestamibi) and BMIPP uptake, and to correlate perfusion and metabolic alterations with regional left ventricular dysfunction in patients with myocardial infarction (MI). ECG-gated dual-isotope myocardial SPECT was performed on 130 patients with MI with sestamibi (555 MBq) and BMIPP (148 MBq). The patients were classified into 3 groups according to PTCA therapy and the interval between the onset of infarction and RI injection (OR time). Group A (n = 56) included patients whose OR time was less than one month and who had undergone successful PTCA, Group B (n = 36) had OR times of less than one month and had conservative medical therapy, and Group C (n = 38) had OR times of over one month. The severity scores of the dual-isotope images were calculated from the defect scores in 9 segments. From the ECG-gated SPECT data with sestamibi, the left ventricular ejection fraction (LVEF; %) and regional wall motion were determined automatically using the QGS program LVEF obtained from gated SPECT correlated well with the severity scores for sestamibi and BMIPP (r = -0.68 and -0.76, respectively). The delta severity scores (BMIPP scores - sestamibi scores) of Group A were significantly higher than those of the other two groups (3.6 +/- 3.0 vs. 1.5 +/- 1.7 and 1.0 +/- 1.4, p < 0.001 ). The rate of dysfunctional segments with normal sestamihi distribution was significantly higher in Group A than in Group C (20.7% vs. 6.7%, p < 0.001). ECG-gated dual-isotope SPECT is useful since myocardial perfusion, fatty acid metabolism and left ventricular function can be analyzed during a single examination, so that this procedure has the potential to provide comprehensive information when evaluating patients with ischemic heart disease.

Enhancement of hepatocarcinogenesis initiated with diethylnitrosamine or N-nitrosobis(2-hydroxypropyl)amine by a choline-deficient, L-amino acid-defined diet administered prior to the carcinogen exposure in rats

Effects of pre-administration of a choline-deficient, L-amino acid-defined (CDAA) diet on hepatocarcinogenesis initiated with diethylnitrosamine (DEN) or N-nitrosobis(2-hydroxypropyl)amine (BHP) in rats were investigated. A pre-administrating period was set as 1 week, because CDAA diet induces liver injuries by this time-point. In a time-course study, male Fischer 344 rats, 6 weeks old, received a 1-week pre-administration of choline-supplemented, L-amino acid-defined (CSAA) or CDAA diet, DEN at a dose of 100 mg/kg body weight by a single intraperitoneal injection, then CSAA or CDAA diet for up to 8 weeks, and were sacrificed 4, 6 and 8 weeks after DEN. CDAA diet administered only after DEN significantly increased the numbers of glutathione S-transferase placental form (GST-P)-positive lesions 4, 6 and 8 weeks after DEN and their sizes 6 and 8 weeks after DEN. CDAA diet administered both before and after DEN similarly increased the numbers and sizes of GST-P-positive lesions, but with a significantly greater degree than obtained by the diet administered only after DEN. In a dose response study, rats received vechicle or DEN, at a dose of 0.001, 0.01, 0.1, 1, 10, 20, 50, 100 or 200 mg/kg body weight, 1 week after the commencement of CSAA or CDAA diet, and sacrificed 8 weeks after vehicle or DEN. The significant increases of the numbers of GST-P-positive lesions were obtained after 50-200 mg/kg body weight of DEN under the CSAA diet administration, whereas those were detected after 10-200 mg/kg under CDAA diet administration. Sizes became significantly larger with only 200 mg/kg body weight of DEN in the CSAA case but with 50-200 mg/kg in the CDAA case. Male Wistar rats received a 1-week pre-administration of CSAA or CDAA diet, vehicle or BHP, at a dose of 600 or 1200 mg/kg body weight, by a single intraperitoneal injection, then CSAA or CDAA diet for 8 weeks, and were then sacrificed. The numbers of GST-P-positive lesions demonstrated significant increment with 1200 mg/kg body weight of BHP by CDAA diet administered only after BHP and, to a significantly greater degree, by the diet administered both before and after BHP. While CDAA diet administered only after BHP did not alter the sizes of GST-P-positive lesions, the diet administered both before and after 600 and 1200 mg/kg body weight of BHP significantly increased the sizes of the lesions. These results indicate that the pre- plus post-administration of CDAA diet enhances hepatocarcinogenesis initiated with DEN or BHP, more than the post-administration only, thus providing a sensitive model to detect weak liver carcinogenic potency of environmental chemicals.

A role of angiotensin-converting enzyme gene polymorphism in left ventricular remodeling after myocardial infarction

BACKGROUND

Left ventricular remodeling (LVR) process is one of the important secondary sequele after acute myocardial infarction (AMI). However, little is known about the relationship between LVR and angiotensin converting enzyme (ACE) gene polymorphism as well as endothelial nitric oxide synthase (ecNOS) gene polymorphism.

METHODS

Coronary angiography and left ventriculography were performed within 24 hours and 30+/-7 days after AMI onset. All consecutive 24 patients (57+/-6 years) had acute anterior MI with one vessel disease of left anterior descending artery and successful revascularization therapy during acute phase. Patients were divided into three groups according to the change of end-diastolic volume index (EDVI)(Delta EDVI = EDVI 1 month-EDVI within 24 hrs); LVR(+) (Delta EDVI>7.0 ml/m(2), n = 5), LVR (-)(Delta EDVI<-7.0 ml/m(2), n = 13), and LVR (+/-)(-7.0<Delta EDVI<7.0 ml/m(2), n = 6) groups. The polymorphisms of ACE and ecNOS gene were determined with PCR method after an extraction of genomic DNA from peripheral leukocytes.

RESULTS

There were no significant difference among three groups as to baseline characteristics, including coronary risk factors, medications, serum CPKmax and patency of infarct-related artery. The incidence of DD genotype of ACE gene is significantly higher in LVR (+) than in the other two groups (0.60; 0; 0, respectively, chi(2) = 13.150, p<0.01). The incidence of D allele of ACE gene is also significantly higher in LVR (+) than in the other two groups (0.70; 0.17; 0.19, respectively, chi(2) = 10.221, p<0.01). Delta EDVI of DD genotype was significantly greater than in the other two groups (DD genotype = 30.1+/-18.1; ID genotype = -13.0+/-27.4; II genotype = -8.2+/-11.5 ml/m(2), respectively, p<0.05). There was no significant difference in ecNOS gene polymorphism among three groups. By stepwise regression analysis, the significant independent predictors of Delta EDVI were EDVI within 24 hrs and DD genotype (F = 16.88 and 8.641, respectively, p = 0.0024).

CONCLUSION

These results showed that left ventricular dilatation is related to DD genotype of ACE gene after successful reperfusion therapy of anterior AMI. Thus, renin-angiotensin system may play an important role in left ventricular remodeling after AMI.

Clinical significance of increased plasma concentration of macrophage colony-stimulating factor in patients with angina pectoris

OBJECTIVES

To determine the effect of macrophage colony-stimulating factor (MCSF) on atherogenesis in patients with coronary artery disease (CAD), we assessed the relation between the plasma concentration of MCSF and the incidence of acute coronary events in patients with CAD.

BACKGROUND

Cytokines such as MCSF play a central role in inflammatory and proliferative responses in patients with acute coronary syndromes. However, the effect of MCSF on the clinical course in patients with CAD is still not known.

METHODS

We measured the plasma MCSF concentration in 142 patients with documented CAD (62 +/- 9 years) and followed up for a mean period of 14 +/- 6 months. The study included 97 patients with stable angina (SA), 45 patients with unstable angina (UA) and 22 age-matched control subjects. The predictors of coronary events were analyzed by using a Cox proportional hazards model.

RESULTS

The mean plasma MCSF concentration in patients with UA was significantly higher than that in patients with SA and in control subjects (981 +/- 277 vs. 693 +/- 223 vs. 680 +/- 158 pg/ml, p < 0.001). The mean plasma MCSF concentration in the 20 patients with coronary events was significantly higher than that in patients without coronary events (1,192 +/- 232 vs. 690 +/- 213 pg/ml, p < 0.001). The predictors of unfavorable outcome were an increased MCSF concentration, the presence of CAD and a low ejection fraction.

CONCLUSIONS

These findings suggest that an increased circulating MCSF concentration reflects atherosclerotic progression in patients with CAD and predicts future cardiac events.

Roles of neuregulin in synaptogenesis between mossy fibers and cerebellar granule cells

Neuregulins (NRGs), a large group of structurally related signaling proteins, are likely to have important roles in the development, maintenance and repair of the nervous system and other selected tissues. We have demonstrated, by using the major form of NRG cloned from the mouse cerebellum that both the soluble form and the membrane anchored form of NRG may serve different functions in synaptogenesis. The soluble form of NRG was produced by proteolytic cleavage of the membrane anchored form of NRG. The proteolytic cleavage was promoted by protein kinase activation. The cleaved form of NRG trans-synaptically regulated the expression of the NMDA (N-methyl-D-aspartate) receptor subunit NR2C as neurally-derived factors, whereas the membrane anchored form of NRG showed a homophilic binding activity between NRGbeta1s. In adult mice the membrane anchored form of NRG was concentrated in neuro-terminals of both granule cells and pontocerebellar mossy fibers. The fact that NRG can be functionally viewed as cell recognition molecules as well as neurotrophic agents suggests new possibilities for the important class of molecules.

Age and organ dependent spontaneous generation of nuclear 8-hydroxydeoxyguanosine in male Fischer 344 rats

8-Hydroxydeoxyguanosine (8-OHdG) is a major oxidative DNA adduct playing roles in senescence, carcinogenesis and various disease processes. High-performance liquid chromatography with an electrochemical detection (HPLC-ECD) method has been widely used to assess organ levels of 8-OHdG, and a recently introduced immunohistochemical approach has made it possible to clarify intra-organ localization. In the present study, these methods were employed to reveal age-dependent changes in nuclear 8-OHdG within various tissues of male Fischer 344 rats between 18 fetal days and 104 weeks of age. 8-OHdG was detected in the nuclei of cerebellar small granule and small cortical cells, cerebral nerve cells, and choroid plexus epithelia of the brain and ependymal cells of the spinal cord; parenchymal cells in the anterior lobe of the pituitary and adrenal glands (mainly cortex); bronchial epithelium of the lung; intra-hepatic bile duct, pancreatic duct, glandular gastric and intestinal epithelial cells; renal tubular epithelial cells (mainly medulla); and spermatogonia and spermatocytes of the testis and seminal vesicle epithelia. The nuclear 8-OHdG levels were high (more than two lesions per 10(6) deoxyguanosines) from 7 days to 104 weeks of age in the brain, 3 to 6 weeks in the adrenal gland, 6 to 104 weeks in the lung, and 3 to 52 weeks in the testis. In the other organs, the nuclear 8-OHdG levels remained low throughout. These findings provide a basis for research dealing with oxidative stress by indicating organ-specific and age- but not aging-dependent changes in the localization of spontaneously generated nuclear 8-OHdG in intact rats. The immunohistochemical approach has advantages for assessing variation of 8-OHdG formation at the cellular level not accessible to the HPLC-ECD method.

[Toxoplasma pericarditis without immunosuppressant disorder detected by polymerase chain reaction of pericardial fluid: a case report]

There have been several case reports, a total of 22 up to the present, of toxoplasma pericarditis. Out of them, in only a few cases the diagnosis was properly made with a proof of the microscopic presence of Toxoplasma gondii. This is the first report of toxoplasma pericarditis in which the presence of Toxoplasma gondii was detected by polymerase chain reaction of pericardial effusion. In addition, the previous reports will be reviewed, and compared to this present case. A 29-year-old woman, without immunosuppressant disorder, suffering from fever and orthopnea was admitted to our hospital. Blood chemistry findings indicated mild liver dysfunction and inflammation. Chest radiography showed cardiac enlargement. Electrocardiography showed sinus tachycardia and ST elevation. Echocardiography revealed a massive pericardial effusion. Pericardiocentesis demonstrated 638 ml of bloody fluid. Cytologic study of the fluid was class II for malignancy, and polymerase chain reaction to tuberculosis was negative. However, a high titer of the anti-toxoplasma antibody of 1: 20,480 (passive hemagglutination) indicated pericarditis caused by Toxoplasma gondii. Subsequently, Toxoplasma gondii was identified in the pericardial effusion by polymerase chain reaction. Clinical symptoms improved after pericardiocentesis, but 2 months later pericarditis recurred. Treatment was started with 800 mg acetylspiramycin daily but failed to improve the symptoms. Because of the development of pleuritis, treatment was changed to sulfadoxine 1,000 mg/pyrimethamine 50 mg. After the treatment with them, her symptoms improved. Only 22 cases of toxoplasma pericarditis have been reported worldwide and 15 of those cases were without immunosuppressant disorder. The usual symptoms at the onset of pericarditis without immunosuppressant disorder are fever, dyspnea and chest pain. Seven patients developed cardiac tamponade. Pericardiocentesis was performed in 8 cases and the pericardial fluid was hemorrhagic in 6. Pericardial thickening was detected in 5 cases. The diagnosis of toxoplasma infection is very difficult, because asymptomatic infection of Toxoplasma gondii is very common. Pericarditis is a disease difficult to confirm the etiology. Detection of Toxoplasma gondii in pericardial effusion by the polymerase chain reaction is very useful for its diagnosis.

[QT dispersion in premature beats produced by extrastimuli from the right atrium and right ventricle]

The difference between the maximum and minimum QT interval measured from a 12-lead electrocardiogram was defined as an index of spatial inhomogeneous repolarization of the ventricular myocardium. The causal relationship between QT dispersion and incidence of ventricular arrhythmias has been pointed out in various heart diseases, but until now it was discussed mainly related to sinus rhythm. QT dispersion in extrasystole may be more important in the development of arrhythmias. We examined 5 cases (mean age 34 +/- 12 years) with a history of paroxysmal supraventricular tachycardia, who underwent electrophysiologic study. Both atrial and ventricular premature stimuli were given at a basic cycle length of 600 msec respectively. The QT interval and the ventricular activation time (VAT) (period from premature test stimulus to the summit of QRS) of the premature beats were measured in a simultaneously recorded 12-lead electrocardiogram. QT dispersion (the difference between the longest QT interval and the shortest QT interval) and VAT dispersion (the difference between the longest VAT and the shortest VAT) were measured. In atrial premature beats, there were no significant changes in the QT dispersion or VAT dispersion when the coupling interval of the premature beats was shortened. In the ventricular premature beats, however, both the QT dispersion and the VAT dispersion tended to increase with the shortening of the coupling interval. We concluded that only a short coupled ventricular premature beat induces greater QT and VAT dispersion. A ventricular couplet with short coupling interval may contribute to the development of ventricular tachyarrhythmias.

Correlation between atrial natriuretic peptide and baroreflex sensitivity in patients with congestive heart failure

The aim of this study was to investigate the relationship between baroreflex sensitivity (BRS) and humoral factors in patients with congestive heart failure (CHF). BRS was assessed by the phenylephrine method in 16 patients with CHF and in 13 healthy controls. The CHF group was subdivided into 2 groups according to BRS (group A: <6 ms/mmHg, n=9; group B: > or =6 ms/mmHg, n=7). BRS was markedly depressed in CHF than in the controls (4.8+/-2.0 vs 8.3+/-3.6 ms/mmHg, p<0.01), and lower in group A than group B (3.3+/-1.3 vs 6.7+/-0.6 ms/mmHg, p<0.01). The plasma human atrial natriuretic peptide (h-ANP) level in group A was significantly higher than in group B (54.6+/-27.6 vs 18.0+/-7.4 pg/ml, p<0.01), and a significant inverse correlation was observed between plasma h-ANP and BRS (r=-0.635, p<0.01). However, there were no significant differences between the 2 groups in plasma catecholamine concentration, plasma renin activity and cardiac function by echocardiogram. These findings suggest that the elevation of endogenous ANP may also serve to compensate for impaired BRS in patients with CHF, in addition to its principal actions, such as diuresis and vasodilation.

Clinical significance of elevated levels of cardiac troponin T in patients with chronic heart failure

Cardiac troponin T, measured by second-generation assay, is a highly sensitive and specific marker of minor myocardial damage. Cardiac troponin T was elevated in patients with severe chronic heart failure; it identifies those with latent and progressive myocardial damage and those who are at increased risk of cardiac events.

Uncommon atrial flutter originating in the left atrioventricular groove: emergence after successful catheter ablation for a left concealed accessory pathway

This report describes a 49-year-old male with concealed Wolff-Parkinson-White syndrome in whom a true uncommon atrial flutter suddenly emerged 2 weeks after successful catheter ablation of a left-sided accessory pathway. The earliest atrial activation during the atrial flutter was recorded at the posterolateral mitral annulus 2 cm proximal to the previous successful ablation site for the accessory pathway. Two applications of radiofrequency (RF) current directed at the supravalvular mitral annulus could not terminate the atrial flutter. A subsequent delivery of RF current directed at the subvalvular annulus, where a local fragmented potential preceded the earliest atrial activation, eliminated the atrial flutter.

[Myocardial distribution of iodine-123-iodophenyl-9-methyl-pentadecanoic acid (9MPA) in patients with acute myocardial infarction: comparison with regional wall motion obtained from technetium-99m-sestamibi gated SPECT]

123I-iodophenyl-9-methyl-pentadecanoic acid (9MPA) is a modified long-chain (15 carbons) fatty acid with a methyl branch on its 9 carbon location. Myocardial SPECT images (two sets, 10 min each) were obtained starting 10 min (early phase) and 50 min (delay phase) after the injection of 160 MBq 123I-9MPA at rest in 10 patients with acute myocardial infarction. The segmental myocardial uptake (% uptake) and clearance (% washout) from early to delay image were calculated by the SPECT data. ECG-gated myocardial SPECT with 99mTc-sestamibi was also performed and segmental left ventricular (LV) wall motion was evaluated using QGS (quantitative gated SPECT) program. The % uptake of LV segments with hypokinetic or akinetic wall motion were significantly lower than those with normokinesis (p < 0.01) for both early and delay phases. The % washout of hypokinetic segments were significantly lower than those of normokinetic regions (p < 0.01), while the % washout of akinetic segments were significantly higher than those of severely hypokinetic segments (p < 0.05). Thus, 123I-9MPA myocardial distribution and clearance thought to be associated with left ventricular regional wall motion.

Inflammatory cell-mediated tumour progression and minisatellite mutation correlate with the decrease of antioxidative enzymes in murine fibrosarcoma cells

We isolated six clones of weakly tumorigenic fibrosarcoma (QR) from the tumorigenic clone BMT-11 cl-9. The QR clones were unable to grow in normal C57BL/6 mice when injected s.c. (1x10(5) cells). However, they formed aggressive tumours upon co-implantation with a 'foreign body', i.e. a gelatin sponge, and the rate of tumour take ranged from 8% to 58% among QR clones. The enhanced tumorigenicity was due to host cell-mediated reaction to the gelatin sponge (inflammation). Immunoblot analysis and enzyme activity assay revealed a significant inverse correlation between the frequencies of tumour formation by QR clones and the levels of manganese superoxide dismutase (Mn-SOD, P<0.005) and glutathione peroxidase (GPchi, P<0.01) in the respective tumour clones. Electron spin resonance (ESR) revealed that superoxide-scavenging ability of cell lysates of the QR clone with high level of Mn-SOD was significantly higher than that with low level of the antioxidative enzyme in the presence of potassium cyanide, an inhibitor for copper-zinc superoxide dismutase (CuZn-SOD) (P<0.001). Minisatellite mutation (MSM) induced by the inflammatory cells in tumour cells were investigated by DNA fingerprint analysis after QR clones had been co-cultured with gelatin-sponge-reactive cells. The MSM rate was significantly higher in the subclones with low levels of Mn-SOD and GPchi (P<0.05) than in the subclones with high levels of both enzymes. The MSM of the subclones with low levels of both enzymes was inhibited in the presence of mannitol, a hydroxyl radical scavenger. The content of 8-hydroxydeoxyguanosine (8-OHdG) by which the cellular DNA damage caused by active oxygen species can be assessed was significantly low in the tumours arising from the QR clone with high levels of Mn-SOD and GPchi even if the clone had been co-implanted with gelatin sponge, compared with the arising tumour from the QR clone with low levels of those antioxidative enzymes (P<0.001). In contrast, CuZn-SOD and catalase levels in the six QR clones did not have any correlation with tumour progression parameters. These results suggest that tumour progression is accelerated by inflammation-induced active oxygen species particularly accompanied with declined levels of intracellular antioxidative enzymes in tumour cells.

Negative U-wave as a predictor of antihypertensive treatment effect on regression of echocardiographic hypertrophy in hypertensive patients

To clarify the mechanism and the predictors of the reduction in left ventricular mass (LVM) induced by antihypertensive drugs, forty hypertensive patients were classified according to the presence of left ventricular hypertrophy (LVH) as a defined by echocardiographic LVM findings (LVH group: 27 patients, non-LVH group: 13 patients) and according to the presence of negative U-waves (NU) (NU group: 10 patients, non-NU group: 30 patients). Negative U-waves appeared in the LVH group only (10 of 27 patients). The hemodynamic determinants were investigated as a mechanism of LVM reduction in 38 of these patients who were treated for 2 years with antihypertensive drugs. In the LVH group, thickness of interventricular septum (IVST), posterior wall thickness (PWT) and LVM increased significantly compared to the non-LVH group. In the NU group, the left ventricular end-diastolic dimension (LVDD) was significantly larger and the relative wall thickness was significantly smaller compared to the non-NU group in the LVH group, with no difference in LVM between the two groups. Negative U-waves disappeared in all cases after treatment. Significant decreases in LVDD and LV wall thickness were observed in the NU group and significant decrease in LV wall thickness in the non-NU group. LVM index was reduced by 24.0% in the NU group and 9.5% in the non-NU group. The disappearance of negative U-waves was an independent predictor of the reduction of LVH.

Inhibition of early-phase exogenous and endogenous liver carcinogenesis in transgenic rats harboring a rat glutathione S-transferase placental form gene

Hepatocarcinogenesis initiated with N-nitrosodiethylamine (DEN) and that initiated by feeding of a choline-deficient, L-amino acid-defined (CDAA) diet were compared in transgenic male Wistar rats harboring a rat glutathione S-transferase placental form (GST-P) gene (GST-P-Tg rats) and non-transgenic (N-Tg) rats. Eight-week-old GST-P-Tg and N-Tg rats were administered DEN intraperitoneally at 100 mg/kg body weight, subjected to a selection procedure with 2-acetylaminofluorene and CCl4, and killed at the end of weeks 5 and 12. Other groups were fed the CDAA diet for 12 weeks and killed. Five weeks after the DEN treatment, numbers and sizes of gamma-glutamyltransferase (GGT)- or GST-P-positive lesions and 8-hydroxyguanine (8-OHG) levels in the livers were significantly less in GST-P-Tg rats than in N-Tg rats. The lesion numbers were unchanged between the ends of weeks 5 and 12 in GST-P-Tg rats, but decreased in N-Tg rats. The lesion sizes were increased in GST-P-Tg rats, but unchanged in N-Tg rats. While the proliferating cell nuclear antigen labeling indices (PCNA L.I.) in and surrounding the lesions were decreased, more prominently in GST-P-Tg rats than in N-Tg rats, the 8-OHG levels were also decreased but similarly in both cases. After 12 weeks on the CDAA diet, the lesion incidences, numbers and sizes, 8-OHG levels, PCNA L.I. in and surrounding the lesions, and liver injury were significantly less in GST-P-Tg rats than in N-Tg rats. These results indicate that insertion of a rat GST-P transgene alters the early phase of exogenous and endogenous rat hepatocarcinogenesis, presumably due to enhanced detoxification by GST-P expressed both transiently during the initiation and chronically in the altered hepatocyte populations.