Evaluation of passive smoking by measuring urinary trans, trans-muconic acid and exhaled carbon monoxide levels

No method has yet been established to evaluate the exposure to tobacco smoke in passive smoking (PS). We therefore conducted a study on the possibility that the levels of urinary trans, trans-muconic acid (MA) and the exhaled carbon monoxide (CO) could be indices of the passive exposure to tobacco smoke. The moderate correlation was observed between urinary MA levels and the number of consumed cigarettes per day in smokers. The mean urinary MA level of the PS (+) group was significantly higher than that with the PS (-) group. Among the PS (+) group, the mean MA level in the urine obtained in the afternoon was higher than that obtained in the morning. A high correlation was observed between the exhaled CO levels and the number of consumed cigarettes per day in smokers. Like the urinary MA level, the mean exhaled CO level in the PS (+) group, too, gave a significantly higher level than in the PS (-) group. Because the biological half life of MA (7.5 +/- 0.85 h) was longer than that of CO (3.0 +/- 0.36 h), the measurement of urinary MA level is recommended for evaluating the exposure of passive smoking. The measurement of exhaled CO levels is useful only for chain smokers and nonsmokers with PS just before measurement.

Prognosis of accidental low back pain at work

Accidental low back pain at the workplace was classified into two groups; 177 cases of the organic type and 176 cases of the non-specific type. Concerning the recuperation period, the length of leave, and the amount of compensation for recuperation, medical cost and leave of absence, a comparison was made between two groups. Regarding age, sex, and the type of work, no difference was found between the organic and the non-specific groups. However, the non-specific group showed lower values than the organic one for the duration of recuperation and leave and the amount of compensation for medical cost and leave of absence. Multiple regression analysis showed that the difference in the type of low back pain had more influence on the duration and cost than that in sex and age. The prognosis of non-specific low back pain is better than that of organic one in terms of cost and duration.

Cloning and expression of a single-chain Fv fragment specific for the human interleukin 18 receptor

We have recently reported the successful purification and characterization of the human interleukin 18 (IL-18) receptor (R) using a monoclonal antibody (MAb) of the IgM kappa class (117-10C) after immunizing mice with cells of the Hodgkin's disease-derived cell line L428. This antibody is specific for the human IL-18R and inhibits the bioactivity of IL-18. Here we report on the polymerase chain reaction (PCR)-assisted cloning and sequencing of cDNAs encoding the variable regions of the light and heavy chains of 117-10C. We expressed the antibody in the form of a single-chain Fv fragment (scFv) in Chinese Hamster Ovary (CHO) cells and purified it from culture supernatants by chromatography. The purified scFv has an affinity for IL-18R of 5.6 x 10(8) M(-1), whereas 117-10C binds to the receptor with an affinity constant of 3.6 x 10(9) M(-1). Since 117-10C is of the IgM class, it is expected to be in the pentamer form and should theoretically therefore bind IL-18R with 10 times the affinity of the single-chain fragment may explain the difference in the affinity constants for the two molecules. The inhibitory efficiency of 117-10C was found to be 6-fold that of scFv in an interferon gamma (IFN-gamma)-inducing assay on the IL-18-responsive cell line KG-1. In conclusion, we have produced a single-chain fragment of a murine anti-human IL-18R antibody that is as potent at binding IL-18 as the parent antibody, and may be useful in neutralizing the cytokine in human conditions associated with high production of IL-18.

Effect of pirarubicin for elderly patients with malignant lymphoma

To determine the effect of a chemotherapy regimen containing pirarubicin, a multicenter clinical trial was performed in naive patients > or = 65 years with malignant lymphoma, between January 1990 and December 1992. The total number of patients was 37 (median age 74.2 years). One of three different types of chemotherapy regimens, which was administered every 3 to 5 weeks, was chosen for each patient at random. Regimen A (THP-COP) included pirarubicin (30 mg/m2; day 1), cyclophosphamide (500 mg/m2; day 1), vincristine (1 mg/m2; day 1) and prednisolone (30 mg/m2; days 1-5), regimen B, modified "CHOP", included doxorubicin (30 mg/m2; day 1), cyclophosphamide (500 mg/m2; day 1) vincristine (1 mg/m2; day 1) and prednisolone (30 mg/m2; days 1-5); regimen C (THP-COPE) included etoposide (80 mg/m2; day 1) in addition to regimen A. The complete response (CR) rate was 60.0%, 45.5% and 62.5% with regimen A, B and C. The partial response (PR) rate with regimen A was 20.0%, 18.2% with B and 25.0% with C. The 50% survival period with regimen A was more than 1,000 days, with C 643 days but it was only 365 days with B. The adverse effects related to these treatments occurred more frequently in regimen B than A and C showing a statistically significant difference. We concluded that chemotherapy regimens containing pirarubicin are useful and safe for the elderly patients with malignant lymphoma.

Elevated serum lipoprotein(a) is a risk factor for left atrial thrombus in patients with chronic atrial fibrillation: a transesophageal echocardiographic study

BACKGROUND

Patients with chronic atrial fibrillation have an increased risk of thromboembolism. Apoprotein(a) has a structural homology with plasminogen, suggesting that lipoprotein(a) [Lp(a)] may produce thrombogenic effects by modulating the fibrinolytic system. However, the role of Lp(a) level in the formation of left atrial thrombus has not been studied. We sought to evaluate whether Lp(a) is a risk factor for left atrial thrombus in patients with chronic atrial fibrillation.

METHODS AND RESULTS

The consecutive series of 150 patients (mean age 67 +/- 8 years) with chronic atrial fibrillation underwent transesophageal echocardiography. Left atrial thrombus was diagnosed by transesophageal echocardiography. Clinical, biochemical, and echocardiographic variables were prospectively collected. Univariate analysis showed that patients with left atrial thrombus (n = 29, 19%) had higher frequency of spontaneous echo contrast (93% vs 55%, P <.0001) than patients without left atrial thrombus (n = 121). Patients with left atrial thrombus also had a significantly higher serum concentration of Lp(a) (34.5 +/- 24.1 vs 17.9 +/- 13.5 mg/dL, P <.0001), a larger left atrium (5.4 +/- 0.9 vs 4.8 +/- 0.7 cm, P <.001), and a lower left atrial appendage peak flow velocity (11.1 +/- 5.4 vs 23.5 +/- 14.6 cm/s, P <.0001). Multivariate regression analysis showed that the Lp(a) concentration (P <.0001) was a significant positive predictor and the left atrial appendage peak flow velocity (P =.0125) was a significant negative predictor of left atrial thrombus. Left atrial thrombus was present in 16 (48%) of 33 patients with Lp(a) level >/=30 mg/dL.

CONCLUSIONS

Elevated serum levels of Lp(a) are strongly associated with left atrial thrombus. These findings suggest that Lp(a) level may be a novel risk factor for left atrial thrombus in patients with chronic atrial fibrillation.

Comparison of arrhythmogenicity of atrial pacing at several right atrial pacing sites: evaluation of canine atrial electrograms during atrial pacing and arrhythmogenicity for atrial fibrillation

The changes in the duration of atrial electrograms and the appearance of AF during atrial pacing were compared among five atrial pacing sites in dogs to clarify the arrhythmogenicity of atrial pacing at different atrial pacing sites. In seven mongrel dogs (15-20 kg), the right atrial surface was exposed by right thoracotomy. Atrial electrograms were recorded via bipolar electrodes with an interelectrode distance of 1.2 mm at four right atrial sites: (1) the high right atrium (HRA), (2) the mid-right atrium (MRA), (3) the low right atrium (LRA), and (4) the center of the pectinate muscle (PM). The duration of the atrial electrograms at these four recording sites were measured during atrial pacing with fixed cycle lengths of 200, 150, and 120 ms delivered at five atrial sites: (1) the HRA, (2) the inferior vena cava (IVC), (3) the right atrial appendage (RAA), (4) Bachman's bundle (BB), and (5) the atrial septum (AS). In each dog, the atrial pacing with the 120-ms cycle length was performed five times at each pacing site to evaluate the inducibility of AF. When AF was induced, the atrial recording site which first showed a fragmented atrial electrogram was considered the initiation site of the AF. AF was induced during 9 of 35 episodes of atrial pacing at the HRA site, 11 of 35 at the IVC site, 5 of 35 at the RAA site, 3 of 35 at the BB site, and none at the AS site. The initiation site of AF was in the HRA site in 11 of 28 episodes of induced AF, in the MRA site in 9 of 28, and in the LRA site in 8 of 28. At each recording site, the shorter the paced cycle length, the longer the duration of the atrial electrogram regardless of the pacing site. During the atrial pacing with the 200-ms cycle length, the HRA pacing resulted in the shortest duration of the atrial electrogram at each recording site in comparison with the other pacing sites. However, during atrial pacing at the two shorter paced cycle lengths, the duration of the atrial electrogram was shorter during the pacing at the BB or AS sites in comparison with the other three pacing sites, i.e., the HRA, IVC, and RAA sites. These results were the same for all atrial recording sites, but the prolongation of the atrial electrogram was most prominent at the HRA and MRA recording sites, which are most likely initiation sites of the induced AF. In the canine atria, (1) the initiation sites of AF were likely to be the HRA, MRA, or LRA sites in comparison with the PM site; and (2) the atrial pacing at the BB or AS sites was considered less arrhythmogenic for AF than the pacing at the HRA, LRA, or RAA sites.

Magnetometric evaluation for the effect of chrysotile on alveolar macrophages

Alveolar macrophages are thought to play an important role in fibrogenesis due to asbestos exposure. In this experiment, we evaluated the effect mainly by unique magnetometry and also by conventional methods such as lactate dehydrogenase (LDH) activity measurement and morphological observations. Alveolar macrophages obtained from Syrian golden hamsters by bronchoalveolar lavages were exposed 18 hours in vitro to Fe3O4 as an indicator for magnetometry and chrysotile for experiments. A rapid decrease of the remanent magnetic field, so called "relaxation", was observed after the cessation of an external magnetic field in macrophages phagocytizing Fe3O4 alone, while relaxation was delayed in those concurrently exposed to chrysotile. Since relaxation is thought due to the cytoskeleton-driven random rotation of phagosomes containing iron oxide particles, chrysotile is considered to interfere with the cytoskeletal function of macrophages. Release of LDH from chrysotile-exposed macrophages into the medium was recognized, but it was not significantly higher than the controls. Apoptosis was negligible in macrophages exposed to chrysotile by the DNA ladder detection, the terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling method and morphological observations. Electron microscopical examinations revealed early necrotic changes in macrophages exposed to chrysotile. These findings indicate that cell magnetometry detects impaired cytoskeletal function due to in vitro exposure to chrysotile.

Myocardial CD36 expression and fatty acid accumulation in patients with type I and II CD36 deficiency

Long-chain fatty acids (LCFA) are one of the major cardiac energy substrates, so understanding LCFA metabolism may help in elucidating the mechanisms of various heart diseases. CD36 is a multifunctional membrane glycoprotein that acts not only as a receptor for thrombospondin, collagen and oxidized low density lipoprotein but also as a receptor for LCFA. We investigated the relationship between CD36 expression in myocardial capillary endothelial cells and myocardial LCFA uptake in patients with CD36 deficiency. We analyzed CD36 expression in blood cells from 250 patients with heart diseases by means of a flow cytometer. In 218 patients, myocardial LCFA scintigraphy was performed with 123I-beta-methyl-p-iodophenyl pentadecanoic acid (BMIPP). In 5 patients, myocardial capillary endothelial cells were examined immunohistochemically for CD36 expression. Eleven patients (4%) showed signs of type I CD36 deficiency (neither platelets nor monocytes expressed CD36). Twenty patients (8%) had type II CD36 deficiency (monocytes expressed CD36 but platelets did not). In all 11 patients with type I CD36 deficiency, no BMIPP accumulation was observed in the heart, but in 13 patients with type II CD36 deficiency, BMIPP accumulation in the heart was focally reduced, but there were no patients without BMIPP accumulation in the heart. Although the myocardial capillary endothelial cells from two CD36-positive patients expressed CD36, those from two patients with type I CD36 deficiency did not. In a patient with type II CD36 deficiency, some capillary endothelial cells displayed patchy CD36 expression. CD36 deficiency was documented in 31 (12%) patients with heart diseases. Because CD36 was not expressed in the myocardial capillary endothelial cells in patients with type I CD36 deficiency, type I CD36 deficiency is closely related to lack of myocardial LCFA accumulation and metabolism in the myocardium.

Change in obstructive pulmonary function as a result of cumulative exposure to welding fumes as determined by magnetopneumography in Japanese arc welders

OBJECTIVES

To examine the effect of chronic exposure to welding fumes on pulmonary function by a direct estimate of fumes accumulated in the lungs.

METHODS

The strength of the residual magnetic field of externally magnetised lungs (LMF) was used as an estimate of fumes accumulated in the lungs. The results of forced spirometry manoeuvres obtained in 143 of 153 male welders in the original sample were cross sectionally evaluated according to LMF. Seven conventional forced spirogram indices and two time domain spirogram indices were used as pulmonary function indices, and height squared proportional correction was performed when necessary.

RESULTS

The distribution of LMF values was considerably skewed towards positive. There was a weak but significant positive relation between age and log transformed LMF. Obstructive pulmonary function indices correlated well with LMF. After adjustment for age and smoking, however, a significant association with LMF was only found with percentage rate of forced expiratory volume in one second (FEV1%) divided by forced vital capacity (FVC) and mu, and average component of assumed time constant distribution of lung peripheral units. Neither FVC nor vital capacity (VC), as indices of restrictive disorders, showed a significant association with LMF. Based on the results of multiple regression analyses, a 0.6% decrease in FEV1% and 0.039 unit increase in mu were expected for each doubling of LMF.

CONCLUSION

Obstructive changes in pulmonary function were found to be related to level of cumulative exposure to welding fume in male Japanese arc welders after controlling for age and smoking, assuming that LMF adequately reflects accumulation of welding fumes in the lungs.

A new scoring system to predict the efficacy of steroid therapy for patients with active myocarditis--a retrospective study

The efficacy of steroid therapy for active myocarditis is controversial, so a new scoring system was constructed based on 6 clinical parameters: (1) the mode of onset of the disease; (2) complications of immune-related systemic disorders; (3) evidence of viral infection; (4) the population of infiltrating inflammatory cells; (5) the appearance of multinucleated giant cells in endomyocardial biopsy specimens; and (6) the duration of active myocarditis. Points from -2 to +2 were assigned to each parameter and the total score was calculated from the 6 parameters. Twenty-one patients with clinically suspected myocarditis, who had been admitted to hospital from 1987, were retrospectively analyzed by this scoring system. Sixteen patients were treated without corticosteroids at presentation, and 5 patients were treated by conventional methods with adjunctive use of corticosteroids. In 10 patients of the non-steroid group myocarditis improved and their mean score was -4.8 at presentation. In 6 patients of the non-steroid group, myocarditis and cardiac symptoms persisted after initial therapy, and their score at presentation was -0.8. In 2 patients of the steroid group myocarditis improved after initial therapy and their score was +2. In 2 other patients of the steroid group, myocarditis and cardiac symptoms persisted and their score was +3. Another patient of the steroid group died from congestive heart failure and his score was -5 at presentation. In 8 of 9 patients with persistent myocarditis, the secondary phase therapy was challenged. Seven patients were treated with corticosteroids and 6 patients improved. Their score at the secondary phase was +2.5. Overall, non-steroid conventional treatment was successful in patients with the scores from -5 to -4, and steroid therapy succeeded in patients with scores from 0 to +6. Although this is a retrospective study, this scoring system is able to predict the efficacy of steroid therapy in patients with clinically suspected active myocarditis.

A comparison of electrophysiologic properties between responders and non-responders to DL-sotalol among patients with ventricular tachyarrhythmia. Importance of the lack of a reverse use-dependent effect on ventricular refractoriness to responders

This study was undertaken to determine whether dl-sotalol can prevent ventricular tachyarrhythmia inducibility that can be predicted from electrophysiologic parameters. The effects of dl-sotalol in 16 patients (ventricular tachycardia (VT) in 11 and fibrillation (VF) in 5) were determined in electrophysiologic studies before and after dl-sotalol (320 mg/day). In 9 of 16 patients (56%) after dl-sotalol, ventricular tachyarrhythmia could not be induced by the entire stimulation protocol (responders). There were significant differences in QT interval (462 +/- 52 vs. 415 +/- 34 msec; p < 0.05) and ventricular effective refractory period (VERP) at 600, 400 and 300 msec (302 +/- 28 vs. 262 +/- 20 msec; p < 0.001, 280 +/- 23 vs. 240 +/- 21 msec; p < 0.001, 256 +/- 24 vs. 222 +/- 12 msec; p < 0.005, respectively) between responders and non-responders. The percentile increases in VERP (% VERP) at 600, 400, and 300 msec in responders were 25%, 26%, and 27%, whereas those in non-responders was 9%, 7%, and 7%, respectively. Isoproterenol administered to responders did not fully reverse the dl-sotalol-induced prolongation of VERP (delta VERP) at 600, 400, and 300 msec, which remained significantly prolonged compared to the baseline (281 +/- 18 vs. 241 +/- 16 msec; p < 0.01, 258 +/- 20 vs. 223 +/- 21 msec; p < 0.01, 247 +/- 22 vs. 202 +/- 16 msec; p < 0.01, respectively). % VERP did not exhibit significant differences at 600 (16%), 400 (15%), and 300 (20%) msec, indicating the lack of a reverse use-dependency. The results suggest that delta VERP in responders did not show reverse use-dependency, and that the phenomenon may account for the efficacy of dl-sotalol.

Expression patterns of costimulatory molecules on cells derived from human hematological malignancies

In order to elucidate the possibility of costimulatory molecules-mediated immuno or immuno-gene therapy for human hematological malignancies, we analyzed 30 hematopoietic cell lines and cells obtained from 48 patients with hematological malignancies for the expression of costimulatory molecules such as CD80 and CD86. The 30 hematopoietic cell lines were composed of 4 cell lines derived from the patients with T-cell acute lymphoblastic leukemia (T-ALL), 3 from Philadelphia chromosome positive ALL (Ph1+ALL), 8 from acute myeloblastic leukemia (AML), 3 from acute promyelocytic leukemia (APL), 8 from chronic myeloid leukemia at blast crisis (CML-BC), 3 from Burkitt's lymphoma and one from follicular cell lymphoma. The expression of CD80 or CD86 was frequent on cell lines derived from the patients with CML-BC or Burkitt's lymphoma, while it was rare on cell lines from T-ALL. Subsequently we analyzed the cells obtained from 48 patients with hematological malignancies, which consisted of 6 samples from patients with ALL, 30 from AML, 2 from CML-BC, 3 from B-cell lymphoma and one from each acute mixed leukemia (AMixL), adult T cell leukemia (ATL), T-cell large granular lymphocytic leukemia (T-LGL leukemia), chronic lymphocytic leukemia (CLL), myelodysplastic syndrome (MDS)-RAEB in T, multiple myeloma (MM) or T-cell lymphoma. Among all the 48 cases, all cases except one case with CLL and two with B cell lymphoma were demonstrated to be negative for CD80 on the neoplastic cells. CD86 and HLA-DR were shown to be expressed in 50% and 88% of total 48 cases respectively. In 30 AML samples, CD86 was positive in 15 cases (50%), which was sharply in contrast with the finding that CD80 was not detected in any AML samples. HLA-DR was expressed in 25 AML samples (83%). We also treated seven human hematopoietic cell lines with IFN-gamma, IL-12 or IL-15 and observed whether these cytokines could induce or enhance the expression of CD40, CD54, CD58 and HLA-DR as well as CD80 and CD86. The present study demonstrated that the expression of CD86 could be upregulated not only by IFN-gamma, but also by IL-12 or IL-15 in some cell lines. These findings suggested the possibility that the absence of CD80 on neoplastic cells may be associated with the lack of efficient anti-tumor immunity in most patients with hematological malignancies and that the immuno or immuno-gene therapy manipulating the expression of costimulatory molecules such as CD80 may be a useful treatment modality for hematological malignancies.

The use of the block cycle length as a safe and efficient means of interrupting sustained ventricular tachycardia and its pharmacological modification

In nine patients who had inducible monomorphic sustained ventricular tachycardia (VT), rapid pacing was performed in 11 episodes of morphologically distinct VT at progressively shorter cycle lengths and VT was interrupted at a critical cycle length. The VT interrupting critical cycle length was defined as the block cycle length (BCL) and the effect of Class I antiarrhythmic drugs were examined. Both the VT cycle length (VTCL) and the BCL were prolonged after administration of either drug. The overall mean ratio of the BCL to the VTCL was unchanged after procainamide administration, but increased after the use of mexiletine. The ratio, however, varied in individual VTs and the BCL after treatment with Class I antiarrhythmic drugs could not be predicted from the ratio baseline value, although the ratio was always > 60% and the hazard of VT acceleration might be avoided if the BCL is used.

T cells with similar T-cell receptor beta-chain complementarity-determining region 3 motifs infiltrate inflammatory lesions of synthetic peptides inducing rat autoimmune myocarditis

Experimental autoimmune myocarditis (EAM) resembles the giant cell myocarditis seen in humans, and recurrent forms lead to dilated cardiomyopathy. EAM has been shown to be a T cell-mediated autoimmune myocarditis. We have previously shown that cDNA encoding Vbeta complementarity-determining region (CDR) 3 from heart- and pericardial space-infiltrating T cells in EAM induced by rod cardiac myosin contains more restricted sequences than that from normal spleen T cells. Recently, it has become apparent that several epitopes of EAM exist in rod cardiac myosin; therefore, T cells infiltrating into lesions may recognize certain epitopes in EAM induced by rod cardiac myosin. In this study, we examined heart- and pericardial space-infiltrating T-cell clonotypes in EAM induced by synthetic peptides of cardiac myosin. EAM was produced by immunization with synthetic peptides corresponding to N-terminally acetylated amino acids 1539 to 1555 of rat cardiac myosin alpha heavy chain. Five of 12 rats receiving synthetic peptides developed macroscopic signs of myocarditis. To examine T-cell receptor (TCR) Vbeta expression and CDR3 of the TCR beta chain of lesion-infiltrating T cells in EAM, total RNA was isolated from heart, pericardial effusion, spleen, lymph node, and peripheral blood. TCR Vbeta expression of the T cells infiltrating the lesions revealed a predominance of Vbeta4. On the basis of single-strand conformation polymorphism analysis for CDR3 of the TCR Vbeta4 chain, heart- and pericardial space-infiltrating T cells were considered to be oligoclonal, whereas spleen, lymph node, and peripheral blood in a rat with EAM and spleen in a native rat were considered to be polyclonal. In the same rat, clonotypes of heart-infiltrating T cells were almost the same as those of pericardial space-infiltrating T cells. Furthermore, on sequence analysis for CDR3 of the TCR Vbeta4 chain, the amino acid motifs were similar among T cells infiltrating into lesions of different EAM rats. In the present study, TCR beta chains of heart- and pericardial space-infiltrating T cells in EAM induced by synthesized peptide consisting of 17 amino acids were examined. Vbeta4+ T cells with similar Vbeta CDR3 motifs that infiltrate the heart and pericardial space may recognize the same epitope.

Expression of the TCL1 gene at 14q32 in B-cell malignancies but not in adult T-cell leukemia

The TCL1 gene was recently cloned as a candidate target within the 14q32.1 breakpoint cluster region observed in T-cell malignancies. We examined the TCL1 gene expression in 21 patients with adult T-cell leukemia (ATL) and 5 cell lines, because ATL is reported to have frequent chromosome 14 band q32 aberrations. However, 20 of the ATL patients and all 5 cell lines lacked any TCL1 expression on northern blot analysis, and TCL1 transcripts were only very faintly detected in the remaining one patient. Expansion of our analysis to include other types of hematopoietic malignancies revealed strong expression of the TCL1 gene in almost all tumor cells of B-cell lineage except myelomas. However, no TCL1 signals were encountered in cells of T-cell or myeloid lineages. In normal human tissues TCL1 was found to be expressed in the spleen, lymph nodes and B-lymphocytes of peripheral blood. These results indicate that TCL1 is not a major target gene for ATL, but that it may play a role in B-cell differentiation and proliferation.

Hypertrophic cardiomyopathy with type I CD36 deficiency

CD36 is a multifunctional membrane-type receptor glycoprotein that reacts with oxidized low-density lipoprotein and long-chain fatty acid (LCFA). A patient presented with hereditary hypertrophic cardiomyopathy (HCM) and type I CD36 deficiency (neither platelets nor monocytes expressed CD36) but showed no myocardial LCFA accumulation. CD36 was expressed in the capillary endothelial cells of the cardiac muscle of a control subject, while the patient's myocardial capillary endothelial cells were completely CD36-negative. These results suggest that type I CD36 deficiency is closely related to hereditary HCM and lack of myocardial LCFA accumulation.

Comparison of electrophysiologic effects of intravenous E-4031 and MS-551, novel class III antiarrhythmic agents, in patients with ventricular tachyarrhythmias

Electrophysiologic effects of intravenous E-4031 and MS-551, novel class III antiarrhythmic agents, were evaluated in 5 and 6 patient with ventricular tachyarrhythmia, respectively. Six patients had sustained ventricular tachycardia (VT) and 5 had ventricular fibrillation (VF). Electrophysiologic study was performed before and after administration of E-4031 and MS-551 [E-4031; loading infusion 9 micrograms/kg for 5 min + 0.15 microgram/kg/min, MS-551; loading infusion 0.3 mg/kg for 5 min + 0.01 mg/kg/min]. The QT intervals were significantly prolonged after administration of E-4031 and MS-551 from 409 +/- 37 to 455 +/- 49 msec (11%), and from 359 +/- 52 to 411 +/- 63 msec (14%), respectively. The QTc intervals were significantly prolonged from 457 +/- 17 to 494 +/- 24 msec (8%), and from 410 +/- 36 to 452 +/- 47 (10%), respectively. There were no significant differences in the QT and QTc intervals between these two agents. The right ventricular effective refractory period (VERP) with E-4031 was prolonged at 600 (from 244 +/- 27 to 270 +/- 31 msec, 11 +/- 2%), 400 (from 222 +/- 23 to 242 +/- 24 msec, 9 +/- 3%), and 300 msec (from 206 +/- 19 to 218 +/- 25 msec, 6 +/- 4%), and those with MS-551 were prolonged at 600 (from 240 +/- 23 to 268 +/- 23 msec, 12 +/- 2%), 400 (from 225 +/- 22 to 250 +/- 24 msec, 11 +/- 4%), and 300 msec (from 213 +/- 14 to 228 +/- 18 msec, 7 +/- 4%). Both E-4031 and MS-551 prolonged VERP in a "reverse" use-dependent manner without changing the conduction velocity. E-4031 prevented the induction of VT in one patient. MS-551 prevented the induction of VT and VF in one patient each. Further evaluation of these selective class III agents may be needed to determine if higher doses are required to achieve the pharmacological effects in patients with ventricular tachyarrhythmias.

[Re-evaluation of the human brachialis muscle by fiber analysis of supply nerves]

The nerve supply to the human brachialis muscle has been investigated by many researchers with gross anatomical and/or microdissectional methods. It has been made clear that the brachialis muscle is innervated by two groups of nerve branches, that is, branches from the musculocutaneous nerve innervating most of the muscle and those from the radial nerve innervating the small inferolateral part. However, the constancy of the radial nerve supply is controversial. Furthermore, some researchers have reported a median nerve supply. On the other hand, the morphological meaning of the double nerve supply by the musculocutaneous nerve from the anterior division of the brachial plexus and by the radial nerve from the posterior division has been generally explained to be a result of the fusion of two muscular primordia, one from the ventral (flexor) premuscular mass and the other from the dorsal (extensor) premuscular mass. The inferolateral part of the brachialis muscle has been considered as a detached portion of the brachioradialis muscle. In contrast with this view, there also has been another view that the brachialis muscle has only one origin from the ventral premuscular mass. The branch from the radial nerve derives from the anterior division of the brachial plexus and uses the radial nerve only as a route to the brachialis muscle by unknown mechanisms. However, the latter view has shown no reliable evidence. Therefore, the purposes of this study are 1) to obtain reliable evidence concerning the anterior derivation of nerve fibers of the branch from the radial nerve (by teasing fibers), 2) to make clear the topographical relationship between the nerve fibers from the musculocutaneous nerve and those from the radial nerve in the brachial plexus (by teasing fibers) and in the brachialis muscle (by an investigation of intramuscular nerve supply) and 3) the topographical relationship between nerve fibers to the brachialis muscle and those to the brachioradialis muscle (by teasing fibers), and 4) to investigate the constancy or the incidence of the radial and median nerve supply. Materials used were sixteen human arms of ten cadavers from the 1996 student course of dissection at Iwate Medical University School of Medicine. Two groups of nerve branches innervating the brachialis muscle, one from the musculocutaneous and the other from the radial nerves, were dissected by a gross anatomical method. The best dissected three specimens were used for the fiber analysis (teasing fibers) of the branches to the brachialis and brachioradialis muscles from the branching points to the nerve roots of the brachial plexus and the investigation of the intramuscular nerve supply in the brachialis muscle. The fiber analysis and investigation of the intramuscular nerve supply were done using an operational microscope (Zeiss, 6-H). The results were as follows: 1) The radial nerve supply to the brachialis muscle was constantly observed (the incidence was 16/16), but no median nerve supply was seen. 2) The branch from the musculocutaneous nerve supplied most part of the brachialis muscle except for the small inferolateral part of the muscle supplied by the radial nerve branch. 3) Communications between the two nerve sources were observed in the brachialis muscle in all three cases. 4) Nerve fibers composing the branch from the musculocutaneous nerve derived from the anterior divisions of the ventral rami of the fifth and sixth cervical nerves. 5) Nerve fibers composing the branch from the radial nerve derived from the anterior divisions of the ventral rami of the sixth and seventh cervical nerves, and were situated in the same bundle of fibers with those from the musculocutaneous nerve at the sixth cervical nerve in the first and third cases (right side of the first and second bodies). 6) Nerve fibers composing the branch to the brachioradialis muscle ran in the same bundles with those to the brachialis muscle in the radial nerve, but were situated in the

Recombinant murine interleukin-12 facilitates induction of cardiac myosin-specific type 1 helper T cells in rats

Autoimmunity after viral myocarditis is considered to be one of the causes of dilated cardiomyopathy. Cytokines are assumed to play an important role in the pathogenesis. We recently reported that interleukin (IL)-2 and interferon (IFN)-gamma mRNA are expressed in the myocardium of rats with experimental autoimmune myocarditis (EAM). However, the role of cytokines in autoimmune myocardial injury in detail is still not clear. Reverse transcription-polymerase chain reaction identified IL-12 (p40) mRNA in antigen-presenting cells in the initial phase of EAM. Cardiac myosin-specific T lymphocytes (MSTLs) were cultured with cardiac myosin peptide (CMP) in the presence of IL-2 and/or IL-12 and were transferred to other naive rats. The results showed that EAM could be effectively induced by transfer of MSTLs cultured with IL-12, whereas transfer of MSTLs cultured with IL-2 was less effective. However, IL-2 acts synergistically with IL-12, and MSTLs cultured with both cytokines most efficiently induce EAM. In vitro experiments showed that MSTLs cultured with both IL-12 and IL-2 produced a much greater amount of IFN-gamma than did MSTLs cultured with either IL-12 or IL-2 alone. The amount of IFN-gamma production was correlated with pathogenicity of MSTLs. Transfer experiments after sorting further demonstrated that the transfer was affected by CD4+ helper T (Th) cells but not by CD8+ cytotoxic T lymphocytes. IL-12 and IL-2 synergistically enhance the pathogenicity of MSTLs. Furthermore, a type 1 Th (Th1) cytokine, IFN-gamma, which is a potent regulatory cytokine of autoimmunity, is produced by MSTLs. IL-12 and IL-2 potentiate the expansion of cardiac myosin-specific Th1 cells and play an important role in the development of autoimmune myocardial injury.