Myocardial mechanical restitution and potentiation partly underlie alternans decay of postextrasystolic potentiation: simulation

We have reported that the postextrasystolic potentiation (PESP) decays in alternans or monotonically, respectively, depending on whether the first postextrasystolic beat interval has a compensatory pause or not, in the canine left ventricle. To get better mechanistic insight into the alternans PESP decay, we hypothesized that the myocardial mechanical restitution and potentiation could partly account for both types of PESP decay. To test this hypothesis, we simulated PESP decay on a computer using a documented equation combining myocardial mechanical restitution and potentiation. We changed the first postextrasystolic beat interval after a fixed extrasystolic beat interval without changing regular and other postextrasystolic beat intervals. The simulated PESP decayed in alternans or monotonically as a function only of the first postextrasystolic beat interval. Thus, the myocardial mechanical restitution and potentiation could partly account for both alternans and monotonic decay of PESP. We conclude that myocardial mechanical restitution and potentiation may partly underlie the initial two alternating beats, the first beat being the most potentiated and the second beat being the most depressed, of alternans PESP decay in the canine heart.

Genetic changes in sweat gland carcinomas

The molecular pathogenesis of malignant appendageal tumors is poorly understood. Immunohistochemical staining, polymerase chain reaction (PCR)-based loss of heterozygosity (LOH) and sequencing analyses were performed in a mixed group of 21 sweat gland carcinomas. LOH was mostly confined to the chromosome arm 17p. None of the remaining 17 tumors showed LOH at any loci. Nuclear accumulation of p53 protein was observed in 3 tumors, all of which also showed LOH of 17p. One eccrine gland adenocarcinoma showed allelic loss of 17p and a Cys 176 Arg mutation in the p53 gene. The other three tumors that showed LOH of 17p, however, had wild-type p53 genes. A clear transition from benign eccrine poroma to porocarcinoma that was associated with p53 protein stabilization and allelic loss was observed in one tumor. One eccrine porocarcinoma/undifferentiated adnexal carcinoma showed prominent microsatellite instability, probably reflecting an underlying defect in DNA mismatch repair. Overexpression of erbB-2 was observed in three tumors. The low frequencies of LOH and p53 alterations in sweat gland carcinomas contrasted with the multiple genetic defects normally observed in cutaneous squamous cell carcinomas, and may be partly explained by the relative protection of cutaneous appendages from ultraviolet light and other environmental mutagens.

Weibull distribution function for cardiac contraction: integrative analysis

The Weibull distribution is widely used to analyze the cumulative loss of performance, i.e., breakdown, of a complex system in systems engineering. We found for the first time that the difference curve of two Weibull distribution functions almost identically fitted the isovolumically contracting left ventricular (LV) pressure-time curve [P(t)] in all 345 beats (3 beats at each of 5 volumes in 23 canine hearts; r = 0.999953 +/- 0.000027; mean +/- SD). The first derivative of the difference curve also closely fitted the first derivative of the P(t) curve. These results suggest the possibility that the LV isovolumic P(t) curve may be characterized by two counteracting cumulative breakdown systems. Of these, the first breakdown system causes a gradual pressure rise and the second breakdown system causes a gradual pressure fall. This Weibull-function model of the heart seems to give a new systems engineering or integrative physiological view of the logic underlying LV isovolumic pressure generation.

Total Ca handling in canine mild Ca overload failing heart

We analyzed total Ca handling of the left ventricle (LV) in the mildly failing heart preparation induced by a temporary intracoronary Ca overloading intervention in eight excised and cross-circulated canine hearts. This Ca intervention consisted of interruption of coronary blood perfusion by Ca-free oxygenated Tyrode perfusion for 10 min followed by high-Ca (16mmol/l) oxygenated Tyrode perfusion for 5 min. This intervention decreased the LV contractility index, Emax (end-systolic maximum elastance), by 40% after restoration of the blood cross-circulation. We expected a Ca overload or paradox failing heart resembling the postischemic stunned heart and being characterized by an increased O2 cost of Emax. However, LV O2 consumption under mechanically unloading conditions decreased by 30% from control without increasing the O2 cost of Emax. To obtain a mechanistic view of this failing heart, we investigated cardiac total Ca handling by our integrative analysis method. In this method, we obtained the internal Ca recirculation fraction (RF) from the decay beat constant of the postextrasystolic potentiation following each sporadic spontaneous extrasystole in these failing LVs. We combined the RF with the decreased Emax and the unchanged O2 cost of Emax in our recently developed formula of total Ca handling. We found that these failing LVs had a slightly but significantly increased RF accompanied by either a slightly increased futile Ca cycling or a slightly decreased Ca reactivity of Emax, or both. Any of these three possible changes can account for the unchanged O2 cost of Emax. This result indicates that the present mildly failing heart has not yet fallen into a typical Ca overload or paradox by the temporary Ca overloading intervention.

The laminin-derived peptide YIGSR (Tyr-Ile-Gly-Ser-Arg) inhibits human pre-B leukaemic cell growth and dissemination to organs in SCID mice

The YIGSR (Tyr-Ile-Gly-Ser-Arg) laminin beta1 chain sequence has an inhibitory effect on tumour growth and the metastasis of melanoma and fibrosarcoma cells. In the present study, we investigated whether the multimeric YIGSR peptide (Ac-Y16) has an antiproliferative effect and/or prevents the metastasis of human pre-B acute lymphoblastic leukaemia cells (NALM6) in severe combined immune deficient (SCID) mice. In in vitro studies, Ac-Y16 significantly inhibited leukaemic cell colony formation and the invasion of NALM6 cells in a Matrigel-based assay. The tumour growth and leukaemic infiltration in peripheral tissues were also analysed in SCID mice 9 weeks after NALM6, Matrigel and Ac-Y16 were subcutaneously co-injected. The weight of the subcutaneous tumours was significantly suppressed by Ac-Y16 in a dose-dependent manner. Flow cytometry analysis showed that the leukaemic infiltration was significantly inhibited in all organs with 1.5-2.0 mg of Ac-Y16. Leukaemic infiltrations in the brain were inhibited with 0.5 mg of Ac-Y16, and those in brain and bone marrow were also inhibited with 1.0 mg of Ac-Y16. With Ac-S16, a control-scrambled peptide, the only significant inhibition of the leukaemic infiltration was observed in bone marrow at a much higher dose. These data suggest that the multimeric YIGSR peptide can inhibit the tumour growth and metastasis of leukaemic cells and may be useful as a potential therapeutic reagent for leukaemic infiltrations.

O(2) cost of contractility but not of mechanical energy increases with temperature in canine left ventricle

We investigated the effects of myocardial temperature on left ventricular (LV) mechanoenergetics in the excised, cross-circulated canine heart. We used the framework of the LV contractility (E(max))-pressure-volume area (PVA; a measure of total mechanical energy)-myocardial oxygen consumption (VO(2)) relationship. We have shown this framework to be useful to integrative analysis of the mechanoenergetics of a beating heart. In isovolumic contractions at a constant pacing rate, increasing myocardial temperature from 30 to 40 degrees C depressed E(max) and increased the oxygen cost of E(max), which was enhanced by dobutamine, in a linear manner. However, the slope of the VO(2)-PVA relation (reciprocal of contractile efficiency) and its VO(2) intercept remained constant. Q(10) values of E(max), the oxygen cost of E(max), and the oxygen cost of PVA were 0.4, 2.1 and 1.0, respectively, around normothermia. We conclude that the temperature-dependent processes of cross-bridge cycling and Ca(2+) handling integratively depress E(max) and augment its oxygen cost without affecting the oxygen cost of PVA as myocardial temperature increases by 10 degrees C around normothermia.

Brain injury does not modify transmissible spongiform encephalopathy caused by intraperitoneal inoculation with Fukuoka-1 strain

The pathogenesis of neuroinvasion in Creutzfeldt-Jakob disease and other transmissible spongiform encephalopathies following the peripheral uptake of a disease agent is still not fully understood. The possibility of neuroinvasion either being established or being accelerated by an insult to the brain has not previously been tested. The experiment described herein was designed to examine this possibility by wounding the brain following an intraperitoneal challenge with a mouse-adapted strain of human transmissible spongiform encephalopathy, Fukuoka-1 strain. The results showed that brain injury introduced in any period before the appearance of cerebral abnormal prion protein deposition modified neither the clinical features, including the incubation period, nor the histopathology of the mice. Our findings suggest that neurovirulence of the agent may not be sufficiently promoted by brain injury.

A chicken monoclonal antibody with specificity for the N-terminal of human prion protein

Chickens were immunized with human prion protein (PrP) peptide H25 (amino acid residues 25-49) coupled to keyhole limpet hemocyanin. From a fusion experiment using the chicken fusion partner cell line MuH1 and immune spleen cells, one mAb, HUC2-13, was generated which reacted with the peptide. HUC2-13 was specific for a pentapeptide (RPKPG) of the N-terminal of the peptide H25. In Western blotting analysis, the mAb reacted with PrP materials from a human Creutzfeldt-Jakob disease (CJD) case and the membrane fraction from normal murine brain, but not with the same materials pretreated with proteinase K. When compared with the HUC2-13 and the conventional mouse mAb 3F4, the background stainings using the HUC2-13 were minimal. In immunohistochemistry, the HUC2-13 stained positively with kuru plaques in brain sections from patients with Gerstmann-Straussler syndrome (GSS), and also reacted with synaptic structures of the CJD patients. However, any immunolabelings using the HUC2-13 were not observed in the section from a patient with amyotrophic lateral sclerosis (ALS) as CJD-negative control. These results indicate that the mAb HUC2-13 is a suitable tool for immunological and diagnostic analyses of prion disease in humans and other mammals.

Clonal dissemination of T-lymphocytes in scid mice from familial hemophagocytic lymphohistiocytosis

BACKGROUND

Although familial hemophagocytic lymphohistiocytosis (FHL) has been considered a disorder of T-cell dysfunction, there is no evidence of the clonal origin of T-cells in this disease.

PROCEDURE

We engrafted mononuclear cells (MNCs) from five FHL patients into scid mice and examined the infiltration of human cells in mouse organs. The characterization of human cells that infiltrated in the mouse organs was then performed.

RESULTS

A diffuse infiltration of human lymphoid cells was detected in scid mice treated with 1 x 10(6) MNCs from one of the five patients. These cells were positive for HLA-DR and CD3, but negative for CD4, CD8, CD20, and CD68, suggesting the infiltration of double negative (DN) T-cells. The MNCs from the other four patients induced murine lymphoma-like disease; T-cell lymphoma in one and lymphoma of unknown origin in three. The characterization of these human DN T-cells was performed. The analysis of the Vbeta repertoire showed no preferential usage of the Vbeta family in MNCs, while the dominant expression of Vbeta13 was detected in T-cells infiltrating in the spleen and lung. A Jbeta analysis showed the restricted usage of Jbeta1.2 for Vbeta13 in these cells, and the clonality of Vbeta13-Jbeta1.2 fragment was confirmed by a single-strand confirmation polymorphism analysis. The analysis of the Valpha repertoire showed that Valpha24 was exclusively used in these DN T-cells, but no usage of JalphaQ for Valpha24 was observed.

CONCLUSIONS

A clonal expansion of T-cells was induced in scid mice by the engraftment of MNCs from an FHL patient. The infiltration of DN alphabeta T-cells bearing invariant Valpha24 T-cell receptor in mouse organs may provide a useful clue to the pathogenesis of FHL. In the patients whose MNCs induced murine lymphoma-like disease, some cytokines or unknown factors that stimulate the growth and the tumorigenicity of murine lymphocytes might be produced by the MNCs engrafted in scid mice. Further study is needed to confirm the validity of our experimental approach and the findings observed in scid mice by using more FHL samples.

Suppression of growth and dissemination in human pre-B leukemia cells by tumor necrosis factor-alpha in scid mice

Tumor necrosis factor (TNF) has been shown to inhibit the growth of ALL cells. Since the systemic administration of TNF for malignancy results in poor response and severe toxicity, future efforts should concentrate on local treatment. Here we examined the suppressive effect of TNF alpha on leukemic cells engrafted in scid mice. NALM6 cells derived from pre-B ALL were injected in scid mice subcutaneously with or without Matrigel. In mice with Matrigel, subcutaneous tumors rapidly increased with time, whereas none of the mice without Matrigel showed any obvious signs of disease or apparent tumors. High levels of leukemic infiltration were observed in peripheral organs in mice with Matrigel by flow cytometry and PCR for human beta-actin mRNA expression, while mice without Matrigel showed low or undetectable infiltration in these organs. Human TNF alpha was also coinjected subcutaneously with NALM6 cells and Matrigel into scid mice. Mice with 10 ng of TNF alpha showed small subcutaneous tumors at 8 weeks, which slowly increased. They were found to have a small number of leukemic cells in peripheral organs by flow cytometry. By PCR, all organs with the exception of lung and brain showed low or undetectable expression of beta-actin. However, a large dose of TNF alpha (100 ng) had no suppressive effect on tumor growth and leukemic infiltration in mouse organs. Similar results were obtained in colony formation of leukemic cells in vitro. To examine the mechanism of the suppressive effect of TNF alpha, the expression of TNF receptors in tumor cells was analyzed by flow cytometry. Parental NALM6 expressed both TNF alpha receptors I (TNFR60) and II (TNFR80), but these expressions were suppressed in tumor cells from mice with Matrigel. Only TNFR80 expression was induced in tumor cells of mice with 10 ng of TNF alpha. The induction of Fas expression was also detected, whereas neither DNA fragmentation nor apoptotic change in histology was observed in tumor cells of mice with TNF alpha. These results suggest that the suppressive effect of TNF alpha on the growth of leukemic cells in scid mice is mediated through the activation of TNFR80 without apoptotic signal.

Ventricular pressure-volume area (PVA) accounts for cardiac energy consumption of work production and absorption

We briefly review that ventricular systolic pressure-volume area (PVA) can predict changes in myocardial O2 consumption (VO2) associated with cardiac work production (positive work) and absorption (negative work). PVA represents the total mechanical energy of cardiac contraction as it is an integral of mechanical energy generated during systole in the cardiac chamber. We have shown that PVA linearly correlates with VO2 under varied pre- and afterload conditions in the left ventricle of the excised cross-circulated canine heart preparation as well as other heart preparations of different species. PVA is the sum of external mechanical work (EW) and mechanical potential energy (PE) which is almost fully convertible to mechanical work without affecting VO2. To compare the energetic effects of cardiac work production and absorption, we varied the timing of the servo pump motion relative to left ventricular (LV) contraction. When the pump fills the LV during diastole and sucks (allows ejection) during systole, cardiac work is produced by the heart, and hence EW > 0. When the pump fills the LV during systole and sucks during diastole, work is absorbed by the heart, and hence EW < 0. The pressure-volume loop rotates counterclockwise when EW > 0. It rotates clockwise when EW < 0. As the result, PVA (= PE + EW) > PE when EW > 0; PVA < PE when EW < 0. We found that VO2 always linearly correlated with PVA regardless of the polarity of EW. Therefore, PVA is the unique determinant of VO2 in a cardiac chamber in a stable contractility.

Detection and sequence diversity of Kaposi's sarcoma-associated herpesvirus (KSHV)/human herpesvirus 8 (HHV-8) DNA

Detection of Kaposi's sarcoma (KS)-associated herpesvirus (KSHV)/human herpesvirus (HHV-8) has been reported frequently in patients with KS associated with acquired immunodeficiency syndrome (AIDS). We examined the presence of the KSHV sequence in 8 HIV-positive patients comprising 5 with KS, 2 with syphilis, 1 with prurigo, and 2 HIV-negative patients with angiosarcoma. Using the polymerase chain reaction, we observed amplification of a DNA fragment of the expected size in 4 patients with KS. Sequencing analysis of the amplified fragments revealed several base substitutions upon comparison with the originally reported sequence. Our results support the hypothesis of a pathogenic role of KSHV in the development of skin lesions in HIV-positive patients with KS, and the sequences of KSHV DNA fragments isolated in this study also demonstrated strain diversity similar to that reported previously.

A new integrative method to quantify total Ca2+ handling and futile Ca2+ cycling in failing hearts

Ca2+ handling in excitation-contraction coupling requires considerable O2 consumption (VO2) in cardiac contraction. We have developed an integrative method to quantify total Ca2+ handling in normal hearts. However, its direct application to failing hearts, where futile Ca2+ cycling via the Ca2+-leaky sarcoplasmic reticulum (SR) required an increased Ca2+ handling VO2, was not legitimate. To quantify total Ca2+ handling even in such failing hearts, we combined futile Ca2+ cycling with Ca2+ handling VO2 and the internal Ca2+ recirculation fraction via the SR. We applied this method to the canine heart mechanoenergetics before and after intracoronary ryanodine at nanomolar concentrations. We found that total Ca2+ handling per beat was halved after the ryanodine treatment from approximately 60 micromol/kg left ventricle before ryanodine. We also found that futile Ca2+ cycling via the SR increased to >1 cycle/beat after ryanodine from presumably zero before ryanodine. These results support the applicability of the present method to the failing hearts with futile Ca2+ cycling via the SR.

Ventricular contractility in atrial fibrillation is predictable by mechanical restitution and potentiation

We recently found that contractility (Emax) of an individual irregularly arrhythmic beat in electrically induced atrial fibrillation (AF) is reasonably predictable from the ratio of the preceding beat interval (RR1) to the beat interval immediately preceding RR1 (RR2) in the canine left ventricle. Moreover, the monotonically increasing relation between Emax and the RR1-to-RR2 ratio (RR1/RR2) passed through or by the mean arrhythmic beat Emax as well as the regular beat Emax at RR1/RR2 = 1. We hypothesized that this Emax-RR1/RR2 relation during irregular arrhythmia could be attributed to the basic characteristics of the mechanical restitution and potentiation. To test this, we adopted a known comprehensive equation describing the force restitution and potentiation as a function of two preceding beat intervals and simulated contractilities of irregular arrhythmic beats with randomized beat intervals on a computer. The simulated Emax-RR1/RR2 relation reasonably resembled the one that we recently observed experimentally, supporting our hypothesis. We therefore conclude that the primary mechanism underlying the varying contractilities of irregular beats in AF is mechanical restitution and potentiation.

A novel neuropeptide, Hym-176, induces contraction of the ectodermal muscle in Hydra

During the course of a systematic non-targeting screening of peptide signal molecules in Hydra, we identified a novel myoactive neuropeptide called Hym-176. The primary structure of Hym-176 was determined to be APFIFPGPKVamide. It specifically and reversibly induced contraction of the ectodermal muscle of the hydra body column in vivo. However, it had no effect on the ectodermal muscle of the tentacles. The structure-activity relationship analysis showed that the sequence of FIFPGPKVamide is a minimal requirement for the myoactivity. Removal of an amide group from the C-terminus completely abolished the activity. By using the antibody specific to Hym-176, the tissue localization of the peptide in hydra was determined immunohistochemically. The intense immunoreactivity was found in the peduncle nerve cells, indicating that Hym-176 is a neuropeptide.

Effects of Ca2+ and epinephrine on Ca2+ recirculation fraction and total Ca2+ handling in canine left ventricles

We investigated the effects of intracoronary Ca2+ and epinephrine on the intracellular Ca2+ recirculation fraction (RF) and total Ca2+ handling in the left ventricle (LV) of the excised cross-circulated canine heart preparation. We analyzed LV postextrasystolic potentiation (PESP) following a spontaneous extrasystole that occurred sporadically under constant atrial pacing. All PESPs decayed in alternans and none decayed monotonically. We extracted an exponential decay component from the alternans PESP, determined its beat constant (taue), and calculated RF = exp(-1/taue). Increased intracoronary Ca2+ slightly increased taue and RF, but epinephrine did not change them, although both agents enhanced LV contractility 2-3 times. Neither Ca2+ nor epinephrine affected the sinusoidal decay of the alternans PESP. These results indicate that RF via the sarcoplasmic reticulum was slightly augmented by Ca2+, but not by epinephrine. We combined these RF data with LV Ca2+ handling O2 consumption data and obtained 40-110 micromol/kg as the total amount of Ca2+ handled in one cardiac cycle in the control and enhanced contractile states. These results indicate that this new LV-level approach seems to better the understanding of the Ca2+ mass dynamics responsible for the mechanoenergetics enhanced by inotropic interventions.

Effects of skin metabolism on percutaneous penetration of lipophilic drugs

Effects of skin metabolism on percutaneous penetration of drugs with high lipophilicity were studied in vitro using rat skin pretreated with and without an esterase inhibitor, diisopropyl phosphorofluoridate [also known as diisopropyl fluorophosphate (DFP)]. Without DFP, about 96% of the total penetrated amount appeared as metabolized p-hydroxybenzoic acid in the receptor fluid after application of butylparaben, whereas about 30% penetrated as intact form after application of propylparaben. On the other hand, metabolized p-hydroxybenzoic acid was not defected in the receptor fluid under pretreatment with DFP. DFP significantly decreased (p < 0.05) the total amount that penetrated after application of butylparaben, but it did not significantly affect that of propylparaben. The results indicate that skin metabolism directly affects total amount that penetrated in the case of highly lipophilic drugs, and it was found that the higher metabolic rate to hydrophilic drugs is, the greater the amount that penetrated the skin would be. Thus, when optimal prodrugs are designed for the purpose of enhancing percutaneous penetration, we propose that the bioconversion rate to parent drugs as well as the lipophilicity of prodrugs becomes an important consideration.

Calcium equally increases the internal calcium recirculation fraction before and after beta-blockade in canine left ventricles

We studied whether intracoronary Ca administration after beta-blockade would increase the internal Ca recirculation fraction (RF) analogously to the Ca administration before beta-blockade. This was performed in excised cross-circulated canine hearts. We analyzed the exponential decay component of the postextrasystolic potentiation (PESP) following a spontaneous extrasystole. All the PESPs decayed in alternans with atrial pacing at a constant rate. We obtained the time constant (tau(e)) of the monoexponential decay component of the alternans PESP. An increment of intracoronary Ca by 1.5 mmol/l enhanced the left ventricular contractility index Emax (end-systolic maximum elastance) by 2.5 times before and after beta-blockade with propranolol. The intracoronary Ca after beta-blockade slightly but significantly increased tau(e), and hence increased RF calculated from tau(e) by RF = exp(-1/tau(e)). This was analogous to the slightly increased tau(e) and RF with Ca before beta-blockade. We speculate that the myocardial cyclic AMP-dependent phosphorylation level would not significantly alter the effect of intracoronarily administered Ca on myocardial Ca handling, in terms of tau(e) and RF.

Effects of an oral adsorbent on cisplatin-induced nephropathy in rats

A 26-week experiment was designed to determine the effect of an oral adsorbent, AST-120 (Kremezin), in rats with cisplatin-induced interstitial nephropathy. We found that creatinine clearance during the 24th week of the experiment was significantly higher in the AST-120-treated rats (n = 11) than in the control animals (n = 11) (1.09 +/- 0.14, vs. 0.63 +/- 0.12 ml/min; p < 0.05). Furthermore, the kidneys, which were examined morphometrically using a computerized image scan, revealed that the AST-120-treated rats had a significantly lower ratio of the tubular cross-sectional area over the cortex and outer medulla cross-sectional area than the control group (0.26 +/- 0.03 vs. 0.38 +/- 0.02; p < 0.05). An additional experiment was conducted to see if the oral adsorbent affects absorption and excretion of intraperitoneally administered cisplatin. There was no difference between the control group (n = 12) and the AST-120-treated group (n = 12) in serum concentration or urinary excretion of cisplatin during a 72-hour period after the injection. The results of our experiments suggest that the oral absorbent, AST-120, blunts progressive deterioration of renal function and nephron architecture in cisplatin nephropathy.

[Relationship between myocardial perfusion state immediately after reperfusion therapy and left ventricular wall motion improvement in patients with acute myocardial infarction]

The relationship between myocardial contrast echocardiography and improvement of the left ventricular wall motion was studied as an indicator of the prognosis of patients with acute myocardial infarction. Ten patients with acute anterior myocardial infarction who demonstrated successful reperfusion (improved to TIMI grade III) and patency of the responsible coronary artery during the chronic stage (one month after the onset) were selected. The contrast study used 2 ml of sonicated iopamidol injected into the left coronary artery. Two-dimensional echocardiograms were taken at the level of papillary muscle on the short axis for recording in VTR. The results of the contrast study were evaluated using a contrast defect score based on the degree and width of the contrast defect. Percent wall motion improvement was measured as an index of improvement of the left ventricular wall motion and CKmax was used for estimating the extent of myocardial necrosis. There was a good correlation between contrast defect score and CKmax (r = 0.853) or % wall motion improvement (r = 0.77). No correlation was found between coronary occlusion time and CKmax nor between coronary occlusion time and % wall motion improvement. The results suggest that if the score is high, recovery of left ventricular wall motion cannot be expected in patients with acute myocardial infarction who demonstrate successful reperfusion. In such cases, myocardial perfusion has not been effectively restored and myocardial necrosis extended over a wide area. If the score is low, recovery of the wall motion can be expected in the chronic stage even though abnormal left ventricular wall motion area is extensive immediately after reperfusion therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

A case of adamantinoid basal cell epithelioma

A 56-year-old woman visited the clinic of dermatology, Yokohama Sakae Kyosai Hospital in May of 1992 with a 5-year history of a blue-gray lesion on her left cheek which had enlarged asymptomatically. The tumor was excised with Z plasty closure. Histopathologically, a loosely encapsulated tumor was situated in the upper to deep dermis. At the periphery of the tumor, there were typical solid basal cell epithelioma (BCE) nests, but within the majority of lobules, intercellular spaces were widened and cells were connected by stellate appendages. Mucoid material filled the spaces and the cells at the periphery palisaded. Histochemical study revealed that the mucoid substance contained hyaluronic acid. An immunohistochemical study was performed using peroxidase antiperoxidase (PAP) method. The antibodies used were anti-epithelial membrane antigen (EMA), anti-carcinoembryonic antigen (CEA), anti-S-100 protein, anti-neurofilament, anti-vimentin, anti-desmin, anti-BRST-1, and anti-BRST-2. The tumor cells and stroma expressed none of these antigens. The tumor was diagnosed as an adamantinoid BCE.

Non-prostanoid thromboxane A2 receptor antagonists with a dibenzoxepin ring system. 2

A series of 11-[2-(1-benzimidazolyl)ethylidene]-6,11-dihydrodibenz[b,e]oxep in-2- carboxylic acid derivatives and related compounds were synthesized and found to be potent TXA2/PGH2 receptor antagonists. Each compound synthesized was tested for its ability to displace [3H]U-46619 binding from guinea pig platelet TXA2/PGH2 receptors. Structure-activity relationship studies revealed that the following key elements were required for enhanced activities: (1) an (E)-2-(1-benzimidazolyl)ethylidene side chain in the 11-position of the dibenzoxepin ring system and (2) a carboxyl group in the 2-position of the dibenzoxepin ring system. The studies also indicated that the TXA2/PGH2 receptor binding affinities of this series of compounds in guinea pig platelet were poorly correlated with those in human platelet. Introduction of substituent(s) to the benzimidazole moiety was effective and sodium (E)-11-[2-(5,6-dimethyl-1-benzimidazolyl)ethylidene]- 6,11-dihydrodibenz[b,e]oxepin-2-carboxylate monohydrate (57) recorded the highest affinity for human platelet TXA2/PGH2 receptor with a K(i) value of 1.2 +/- 0.14 nM. It demonstrated potent inhibitory effects on U-46619-induced guinea pig platelet aggregation (in vitro and ex vivo) and human platelet aggregation (in vitro). Compound 57, now designated as KW-3635, is a novel, orally active, and specific TXA2/PGH2 receptor antagonist with neither TXA2/PGH2 receptor agonistic nor TXA2 synthase inhibitory effects. It is now under clinical evaluation.

Latent infection of SCID mice with herpes simplex virus 1 and lethal cutaneous lesions in pregnancy

Some SCID mice survived primary infection with herpes simplex virus 1 without the development of peripheral lesions but established coculture-positive ganglionic latency when a low dose of a wild-type strain was inoculated intracutaneously. The latency was also evidenced by the development of the fatal zosteriform skin lesions and the isolation of the virus during pregnancy. We consider that the viral entry into neurons without successive replication, rather than the arrest of the lytic infection within the cells, is an important mechanism in the establishment of latency.

Localized multiple neurofibromas

Two cases of localized multiple neurofibromas are reported. The patients had fairly large, closely grouped neurofibromas limited to a circumscribed part of the body, a very different clinical feature from segmental neurofibromatosis, but with otherwise had typical histopathological features. Possible aetiology is discussed.

[Electrocardiographic criteria for the diagnosis of the left septal fascicular block and its frequency among primarily elderly hospitalized patients]

Characteristic electrocardiographic findings of the left septal fascicular block consist of a prominent anterior QRS force. Therefore, the following criteria were proposed for the diagnosis of left septal fascicular block, based on the normal limits of the R and S waves and R/S of V1 and V2. (1) Right ventricular hypertrophy, complete right bundle branch block, preexcitation (Type A), high posterior infarction, hypertrophic cardiomyopathy and abnormality of the thorax or intrathoracic tissues which might cause marked counterclockwise rotation around the longitudinal axis of the heart, should be excluded. (2) One of the following two criteria should be satisfied. (i) R/Sv1 greater than 2, and Rv1 greater than or equal to 5 mm, (ii) R/Sv2 greater than 2, and Rv2 greater than or equal to 15 mm, or Sv2 less than 5 mm. The frequency of left septal fascicular block diagnosed by these criteria was 3.5% among all patients of a hospital mainly consisting of elderly patients. This frequency was less than that of the left anterior fascicular block or complete right bundle branch block, but it was higher than that of the complete left bundle branch block or bilateral bundle branch block.

Localization of herpes simplex virus type 1 in sebaceous glands of mice

The distribution of HSV-1 during the development of zosteriform skin lesions in SCID mice was analyzed by immunofluorescence and electron microscopy. The virus initially appeared within certain keratinocytes, sometimes surrounded by keratinocytes whose surfaces were also positive for the antigens, in the lower epidermal layers including the hair follicles, and then extended upward to the entire epidermis and downward to the sebaceous glands 1-2 days later, when no macroscopic skin lesion was seen. The affected epidermal cells subsequently degenerated and lost their viral antigens within a day, when the zosteriform lesion then became evident. This was followed by a degeneration of the dermis. The sebaceous glands eventually degenerated in 10 days, but some glands in the necrotic skin areas preferentially retained HSV-1. The horizontal spread of the virus in the epidermis beyond the first invaded dermatome occurred much later. In mice passively immunized with specific immune serum, viral antigens were observed even 20 days after the infection in sebaceous glands in necrotized areas. Therefore, HSV-1 appears to spread first via the extracellular fluid among the keratinocytes after being shed from nerve endings, and then produces a successive degeneration of the affected keratinocytes which may prevent any further extension of horizontal viral spread. The pilosebaceous apparatus is possibly acting as a site not only for the replication of HSV-1 with a delayed cytopathic effect, but also as an area that is temporarily sheltered from host defense mechanisms.

Pathology and angiographical studies on urogenital organ system induced by idiopathic hemorrhage in male E1 mice

Urogenital organ system induced by idiopathic hemorrhage in sudden died male E1 mice were investigated macro- and histopathologically and angiographically. The mortality of the male E1 mice with brief life span was 85% during observation period for 33 weeks, and about half of the male E1 mice died between 10-week-old and 20-week-old. In all dead mice, urine retention was prominent, and the seminal vesicle or the coagulating gland, especially the bulbocavernosus muscle had severe hemorrhage. There was coagulated blood mass in the urethral lumen and the lumen of the seminal vesicle and the coagulating gland. Further, in pars spongiosa, coagulated blood mass occupied the most area of the corpus spongiosum penis and corpus cavernosum penis with severe hemorrhage. Angiographically, the penile artery in not affected male E1 mice was thinner than that in control mice.

Abnormal isoform of prion protein accumulates in follicular dendritic cells in mice with Creutzfeldt-Jakob disease

We established that follicular dendritic cells (FDCs) are the site of abnormal prion protein (PrPCJD) accumulations in lymphoid tissues from mice infected with Creutzfeldt-Jakob disease. Evidence of positive FDC staining was observed in Creutzfeldt-Jakob disease-infected mice irrespective of the inoculation route, while no such staining was seen in the control mice. We also found that the severe combined immunodeficiency mouse trait is transmittable via the intracranial route but not via the intraperitoneal route. Mice with severe combined immunodeficiency did not have PrPCJD accumulation in FDCs.

Fine structure of atrial natriuretic peptide(ANP)-granules in the atrial cardiocytes in the pig, cattle and horse

In the pig, cattle and horse, the right and left atria and ventricles were examined by immunohistochemistry, and the right atrial and auricular cardiocytes were studied by transmission electron microscopy. Moreover, ANP-granules in the cardiocytes were analyzed by ultrastructural morphometry. Immunohistochemically, the most intensely ANP-reacted cardiocytes were localized in the right auricle, particularly more prominent in the pig and cattle than in the horse. Ultrastructurally, ANP-granules were located principally in the perinuclear region associated with the Golgi apparatus and throughout the sarcoplasmic layers. They were classified into 2 types, A and B. A-granule had a conspicuous electron-dense core enveloped by a membrane. B-granule had a fibrillogranular core enveloped by an indistinct membrane. By TEM equipped with a goniometer stage, a part of the limiting membrane of B-granules became visible as the stage tilt progressed. By ultrastructural morphometry, the number of each type of granules was significantly greater in the pig and cattle than in the horse. In the pig and cattle, the total number of both types of granules in the auricular cardiocytes was significantly greater than that in the atrial ones. The diameter of each type of granules was significantly larger in the pig and cattle than in the horse. The diameter of A-granules was significantly larger than that of B-granules.

An immunohistochemical study of mixed tumor of the skin

An asymptomatic tumor developed on the upper lip of a 63-year-old man. Histologically, the tumor contained glandular and cystic structures forming many branching lumina, and many scattered single cells in an abundant mucoid to chondroid stroma. The tumor was diagnosed as mixed tumor of the skin. Histochemically, the cells composing the tubular structures contained neutral mucopolysaccharides and the stroma, acid mucopolysaccharides. Immunohistochemically, the cells of the glandular and cystic structures showed epithelial and sweat gland differentiation (EMA-, CEA-, BRST-1- and BRST-2-positive), while the cells scattered in the stroma showed a tendency toward myoepithelial differentiation (S-100 protein- and vimentin-positive).

Fine structure of atrial natriuretic peptide (ANP)-granules in the atrial cardiocytes of the mouse, rat and Mongolian gerbil

Mouse, rat and Mongolian gerbil atrial and ventricular cardiocytes were examined by immunohistochemistry, and the right atrium including the auricle was examined by transmission electron microscopy. In addition the ANP granules of both right atrial and auricular cardiocytes were analyzed by ultrastructural morphometry. ANP immunoreactivity was detected in the atria of all three species, and the most intensely reacting cardiocytes were localized in the right auricular part of the atrium. These reactions were more prominent in the mouse and rat than in the Mongolian gerbil. ANP immunoreactivity was not detected in the ventricular myocardium of any of the three species, but was occasionally seen in the subendocardium of the ventricular septum. Ultrastructurally, the ANP granules in the auricular and atrial cardiocytes were observed to be variable in size and number, and these granules were located principally in the paranuclear region in association with the Golgi apparatus, and found throughout the sarcoplasmic layers in all three species. The ANP granules were classified into two types: A-granules containing a conspicuous electron-dense core possessing a membrane, and B-granules having profiles with a fibrillogranular, less electron-dense core than the A-granules and an indistinct membrane. The features of these granules were similar in all three species. When examined by ultrastructural morphometry, the number of each type granule and the total number of granules in the right auricular and atrial cardiocytes of the mouse and rat were significantly greater than in the Mongolian gerbil. The total number of granules in the right auricular cardiocytes was significantly greater than in the cardiocytes of the right atrium exclusive of the auricle, however, there was no significant difference between the number of A-granules and B-granules in the three species. The diameter of each type of granule in the right auricular and atrial cardiocytes of the mouse and rat was significantly greater than in the Mongolian gerbil, and the diameter of the A-granules was significantly greater than the diameter of the B-granules in all three species.

Centipede bites in Japan

Five cases of centipede bites are reported. The patients showed erythema in response to swelling, and/or paresis around the sites. They had been bitten by Scolopendra subspinipes mutilans Koch or Scolopendra subspinipes multidens Newport. There was no species-specific reaction to the bite, so the variety of reactions seen was thought to be due to patients' individual differences. Treatment included local anesthesia, systemic and/or topical corticosteroids, and administration of a biscoclaurin alkaloid, as needed according to the severity of the lesions.

Synthetic anthracyclines: regiospecific total synthesis of D-ring thiophene analogues of daunomycin

The key anhydride 2-acetoxy-[2-carboxy-5-(trimethylsilyl)thiophen-3-yl]acetic acid anhydride (8), prepared from (2-carboxythiophen-3-yl)acetic acid (5), underwent a strong base-induced cycloaddition reaction with the chloroquinone acetal (11) to give the 7,7-ethylenedioxy-2-trimethylsilyl-6,7,8,9- tetrahydroanthra[2,3-b]thiophene-5,10-dione (12) regioselectively. Similarly, the regioisomeric 8,8-ethylenedioxy-2-trimethylsilyl-6,7,8,9-tetrahydroanthra[2,3-b] thiophene- 5,10-dione (30) was obtained by the strong base-induced cycloaddition reaction of 8 with the chloroquinone acetal (29). These cycloadducts (12 and 30) were converted to D-ring thiophene analogues (28 and 38) of daunomycin (1a). Another D-ring thiophene analogue (42) which has a trimethylsilyl substituent in the D-ring was also prepared.

Cerebral amyloid in mice with Creutzfeldt-Jakob disease is influenced by the strain of the infectious agent

We examined Fukuoka-1 and Fukuoka-2 mouse-adapted Creutzfeldt-Jakob disease strains. Mice infected with the Fukuoka-2 strain have a higher incidence of kuru plaques, a higher concentration of proteinase-resistant prion protein, and a higher infectivity titer than do mice with the Fukuoka-1 strain. Thus, it must be kept in mind that there is a difference in the strain of the infectious agent in murine Creutzfeldt-Jakob disease.

Organ distribution of proteinase-resistant prion protein in humans and mice with Creutzfeldt-Jakob disease

We attempted to clarify the organ distribution of human and murine proteinase-resistant prion protein (PrPCJD) in Creutzfeldt-Jakob disease (CJD), and to measure the concentration of PrPCJD, using a semi-quantitative Western blot analysis. Human PrPCJD was restricted to the central nervous system, whereas murine PrPCJD was present in the central nervous system and in the lymphoreticular system at the end stage of CJD. PrPCJD concentration in the central nervous system of mice was almost identical to that of humans. The minimum wet weight of an organ with a positive reaction was 0.3 mg for brain, 1 to 3 mg for spleen, 3 mg for spinal cord, 3 mg for lymph node, 10 mg for thymus and 10 to 30 mg for intestine of the CJD-infected mice. There were no immunoreactions in purified PrPCJD fractions from 300 mg of spleen, lymph node, liver or peripheral nervous systems of humans, nor in 300 mg of liver, lung or kidney of CJD-infected mice. Within the limits of our method, the distribution of murine PrPCJD differed from that of human PrPCJD. Antibodies on the Western blot membrane from murine spleen PrPCJD fractions stained the kuru plaques in the CJD-infected mouse brain. Therefore, PrPCJD in the murine spleen probably shares the epitopes of the antigen in the murine kuru plaques. Although the immunological detection of PrPCJD does have limits of sensitivity, PrPCJD concentrations did correlate with infectivity titres in scrapie-infected or CJD-infected mice.

Spotted fever group rickettsia in dogs in Japan

Prevalence of antibody against spotted fever group-rickettsia in dogs (14/134) from the northern part of Shikoku Island, where spotted fever group rickettsia infection in human is endemic, is significantly higher than that in dogs (4/189) from nonendemic areas.

Host genetic control of incubation periods of Creutzfeldt-Jakob disease in mice

Host genetic control of the incubation period of Creutzfeldt-Jakob disease (CJD) was studied using various inbred strains of mice, including B10 congenic strains. Various incubation periods were found in mice injected either intracerebrally or intraperitoneally with the Fukuoka 1 strain of the CJD agent; NZW/Sea and A/JJms had the shortest, and B10.AKM/Ola and C57BL/6J the longest, incubation periods. Length of the CJD incubation period did not correlate with the genetic markers tested, i.e. the murine major histocompatibility (H-2) complex (which has previously been reported to be linked to a gene influencing CJD incubation period in mice), coat colour or sex genes. In NZW/Sea x C57BL/6J F1 hybrid mice the CJD incubation periods were similar to that of the parent with the longest incubation period. Incubation periods of the backcross progeny from F1 and NZW/Sea were intermediate between those of the parental mice and had a unimodal distribution pattern. A similar observation was made on the progeny of the A/JJms x C57BL/6J mating. On the other hand, the length of incubation period for the NZW/Sea x B10.AKM/Ola F1 hybrid fell between those for the two parents and the NZW/Sea x A/JJms F1 hybrid had a significantly longer incubation period than those of the two parents. These results suggest that polygenes probably control the length of the CJD incubation period in mice.

Fine structure of the mandibular gland in volcano rabbit

The mandibular glands of 6 male and 6 female volcano rabbits were examined by means of light and transmission electron microscopy. The acinar cells of the glands were seromucous in nature, and contained faintly basophilic granules. The cells were classified into the light cells containing granules of low or moderate densities and the clear cells having polygonal granules of low density. The preacinar cells were occasionally observed at the site between acinus and intercalated duct. These cells had many weakly basophilic granules which contained fine granular materials of moderate density. The intercalated ducts were composed of light cells containing cored granules. The striated duct cells consisted of light cells and dark cells. Both of them contained a few vacuoles and vesicles, but no secretory granules. No sex-and age-related differences were observed in the mandibular gland of the volcano rabbit. The mandibular gland of the volcano rabbit was similar to the rabbit mandibular gland rather than the pika mandibular gland morphologically.

Histopathological and immunohistochemical study of amyloidosis cutis nodularis atrophicans--comparison with systemic amyloidosis

Three cases of amyloidosis cutis nodularis atrophicans (ACNA) were investigated histologically and immunohistochemically to determine the nature and origin of the deposited amyloid. A pulmonary lesion from a case of nodular pulmonary amyloidosis, and cutaneous lesions from three cases of primary systemic amyloidosis, two cases of secondary systemic amyloidosis and three cases of secondary cutaneous amyloidosis following basal cell epithelioma were also examined for comparison. Histology showed infiltration of numerous plasma cells adjacent to amyloid deposits in ACNA and nodular pulmonary amyloidosis, but not in systemic amyloidosis. Immunohistochemically, the cytoplasm of the plasma cells was stained with anti-immunoglobulin light chain or anti-Bence-Jones protein antisera or both, and amyloid material stained with anti-AL antiserum in ACNA and nodular pulmonary amyloidosis. These results suggest that, in ACNA, the plasma cells may produce and secrete immunoglobulin light chains or Bence-Jones protein or both, which undergo proteolysis to protein AL or amyloid fibril proteins which have the same immunoglobulin determinants as protein AL. The product is then deposited locally to form nodules in the dermis.

Herpes simplex virus type 1 infection in mice with severe combined immunodeficiency (SCID)

Herpes simplex virus type 1 (HSV-1) infection in mutant mice with severe combined immunodeficiency (SCID mice), i.e., mice in which the differentiation of both T and B lymphocytes is severely impaired, was studied. All control (infected and not treated with antibodies or with immune spleen cells) SCID mice were dead by 17 days after intracutaneous injection in the right midflank with 1 x 10(5) PFU of a virulent HSV-1 strain, Hayashida. Immunization with an avirulent strain of HSV-1 (SKa) did not protect them from death or prolong the survival time. Tissue virus titration of infected mice killed at various times after inoculation detected infectious virus in various organs, dorsal root ganglia, spinal cord, brain, kidney and adrenal gland in addition to the inoculation site of the skin in SCID mice, whereas virus could be detected only in the inoculation site and the nervous tissues in euthymic BALB/c mice, and in the adrenal gland from only one out of 17 nude mice. Human gamma globulin containing neutralizing antibody against HSV-1 prolonged the survival time but did not protect SCID mice from death. Transfer of spleen cells from immunized BALB/c mice protected the infected SCID mice from death. Treatment of spleen cells with anti-Thy 1.2 monoclonal antibody and complement abolished the protection.

Fine structure of the parotid gland in the pika and the volcano rabbit

The parotid glands of the pika and the volcano rabbit were examined by light and transmission electron microscopy. The acinar cells of the pika consisted of light cells containing basophilic granules of low density, while in the volcano rabbit the acinar cells consisted of light and dark cells containing acidophilic granules of moderate density. Intercalated duct cells were composed of light cells containing a few granules of moderate density. These segments of the two animals were similar in morphology. The striated duct cells in both species were composed of light and dark cells. Most of those in the pika contained a few moderately dense granules. In both animals, no myoepithelial cells were detected around the acini, intercalated ducts or striated ducts, while nerve terminals were observed among the adjacent acinar cells.

Protective effect of recombinant murine interferon beta against mouse hepatitis virus infection

Recombinant murine interferon beta (rMuIFN-beta) protected susceptible C57BL/6 mice against lethal mouse hepatitis virus (MHV) infection. rMuIFN-beta was life saving if it was given intraperitoneally beginning 21 h before infection and daily thereafter for 9 days, and lengthened the survival time if given from 3 h after infection. rMuIFN-beta treatment beginning 24 h after infection was ineffective. The survival rate was dose-dependent, and the 50% effective dose of rMuIFN-beta for survival was 1780 IU per day. rMuIFN-beta pretreatment inhibited virus growth completely in the brain and moderately in the liver and spleen and prevented severe hepatic lesions. rMuIFN-beta also protected beige mice and cyclophosphamide-treated mice against MHV infection, suggesting that activation of natural killer cells or T-cells by rMuIFN-beta is not critical for protection.

Lack of effect of thymus and spleen on the incubation period of Creutzfeldt-Jakob disease in mice

Genetically athymic and asplenic (Lasat), athymic (Nude), asplenic (Dh) or normal littermate (Hetero) mice with a BALB/c genetic background were injected either intracerebrally or intraperitoneally with a 1% or 10% homogenate of mouse brains infected with the Fukuoka 1 strain of the Creutzfeldt-Jakob disease (CJD) agent. As there were no significant differences in incubation periods among the five groups (Lasat, Nude, Dh, Hetero and BALB/c) inoculated with the same dilution, via the same route, it was concluded that cell-mediated immunity dependent on the thymus plays no significant role in host defence against the CJD agent, and the spleen, a critical site of agent replication, is apparently not an obligatory source from which infection spreads to the central nervous system.