Prevalence of HTLV-I in leprosy patients in two sanatoriums in Japan

To determine the association between leprosy and HTLV-I, 450 and 394 leprosy patients in two sanatoriums in Japan (Sanatorium-A in Okayama prefecture and Sanatorium-B in Gunma prefecture) were investigated serologically for antibodies to HTLV-I. Serology was positive for HTLV-I in 38 (8.4%) of 450 leprosy patients in Sanatorium-A and in 34 (8.6%) of 394 patients in Sanatorium-B. Prevalence was much higher than that in the general population of these areas in Japan. A large proportion of HTLV-I-positive patients in both sanatoriums came from HTLV-I nonendemic areas in Japan, suggesting that HTLV-I infection occurred after the patients arrived at the sanatoriums. Infection through sexual contact or reuse of needles for frequent vaccination are possible routes of infection for HTLV-I in these cases.

Protective effects of Mu-Fang-Ji-Tang against myocardial injury in a murine model of congestive heart failure induced by viral myocarditis

The effects of Mu-Fang-Ji-Tang (TJ-36), a traditional Chinese herbal medicine, were studied in a murine model of congestive heart failure induced by viral myocarditis. In the group of animals treated with Mu-Fang-Ji-Tang in a dose of 1.5g/kg/day, the heart weight to body weight ratio was significantly lower than in the control group (p<0.01). Histopathological grades were also significantly lower in the Mu-Fang-Ji-Tang treated group than in the placebo group (p<0.05). Furthermore, survival was increased in the Mu-Fang-Ji-Tang treated group, versus the control group (p<0.05). In vitro, murine J774A.1 macrophages inoculated with encephalomyocarditis virus produced a significantly greater amount of nitrites compared to non-activated macrophages. Mu-Fang-Ji-Tang added to the cells (25, 50, 75, 100 microg/ml) concomitantly with the encephalomyocarditis virus inhibited nitrite formation in a concentration-dependent manner. Mu-Fang-Ji-Tang showed a protective effect against myocardial injury leading to congestive heart failure in this animal model.

Cardioprotective effects of beraprost sodium against experimental ischemia and reperfusion as compared with propranolol and diltiazem

We compared the cardioprotective effects during experimental ischemia and reperfusion of beraprost sodium (beraprost), a prostacyclin analog, with those of propranolol and diltiazem. Coronary perfused guinea-pig right ventricular free wall preparations were subjected to 30 min no-flow ischemia with or without drugs, followed by 60 min reperfusion without drugs. In control preparations, decrease in contractile force and increase in resting tension were observed during the no-flow period. On reperfusion, contractile force returned to less than 50% of preischemic values. Beraprost, at 0.1 microM, showed no inotropic effect under normoxic condition and during the no-flow period, but significantly enhanced the recovery of contractile force after reperfusion to about 80% of control values. Propranolol (30 microM) or diltiazem (10 microM) produced similar enhancement of recovery of contractile force after reperfusion, but these two drugs decreased the contractile force under normoxic conditions to less than 20% of control values. Thus, the cardioprotective effect of beraprost was different from those of propranolol and diltiazem in that it was not accompanied by cardiosuppressive effects.

Short-term and long-term effects of low-density lipoprotein (LDL) apheresis on restenosis after percutaneous transluminal coronary angioplasty (PTCA): is lowering Lp(a) by LDL apheresis effective on restenosis after PTCA?

It has been reported that serum lipoprotein(a) (Lp[a]) levels in patients with restenosis after percutaneous transluminal coronary angioplasty (PTCA) were significantly higher than in patients without restenosis. In this study, we evaluated the preventive effect of LDL apheresis on restenosis after PTCA in patients with hypercholesterolemia. For 10 patients who had shown a serum cholesterol level of more than 220 mg/dl despite treatment with antihypercholesterolemic drugs, LDL apheresis was conducted every 2 weeks after a successful PTCA until restenosis could be checked. In 4 patients, LDL apheresis was conducted for 2 years. LDL apheresis significantly reduced serum cholesterol from 248 +/- 22 mg/dl to 135 +/- 26 mg/dl and Lp(a) from 42 +/- 34 mg/dl to 21 +/- 16 mg/dl. The average degree of stenosis in the 11 lesions undergoing PTCA was 92 +/- 6% before PTCA, 35 +/- 10% immediately after PTCA, and 38 +/- 19% at 3 to 4 months after PTCA. Restenosis was observed in only 1 lesion. In 4 patients who received LDL apheresis for 2 years, restenosis did not occur in any of the 4 lesions treated. We concluded that LDL apheresis was an efficacious therapy to prevent restenosis after PTCA in patients with hypercholesterolemia.

Deletion of Epstein-Barr virus latent membrane protein 1 gene in Japanese and Brazilian gastric carcinomas, metastatic lesions, and reactive lymphocytes

A 30-bp deletion in the Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) gene has been reported in nasopharyngeal carcinoma and EBV-associated malignant lymphomas. Information on this deletion in EBV-associated gastric carcinoma (EBVaGC) is limited. The association of gastric carcinoma (GC) with EBV was examined by EBV-encoded RNA (EBER) in situ hybridization in 510 patients from Japan and 80 patients from Brazil. We studied the prevalence of 30-bp LMP1 gene deletion in EBVaGC in Japan (29 cases) and Brazil (four cases) in comparison with the corresponding EBER1-positive metastatic lesions in lymph nodes (10 cases) and EBV-infected reactive lymphocytes from dissected nonmetastatic lymph nodes (22 cases), microdissected non-neoplastic gastric mucosa of EBVaGC (five cases), and EBV-nonassociated GC (25 cases). We studied the status of the LMP1 gene by Southern blot hybridization of polymerase chain reaction products obtained after amplification with primers flanking the site of the deletion. We also performed EBV typing and LMP1 protein immunohistochemistry. EBV DNA was amplified by polymerase chain reaction in 30 of 33 EBVaGC cases, 8 of 10 metastatic carcinomas, 14 non-neoplastic tissues from 27 EBVaGC cases, and 12 of 25 non-EBV-associated GC cases with EBER1-positive lymphocytes. The 30-bp LMP1 gene deletion was observed in 23 of 26 (88.5%) cases of EBVaGC from Japan and two of four (50%) cases of Brazilian EBVaGC as compared with EBER1-positive reactive lymphocytes from 11 of 14 (78.6%) EBVaGC cases and 9 of 12 (75%) cases of non-EBV-associated GC. The variant type (the 30-bp deletion variant or nondeleted wild type) of LMP1 gene was the same among reactive lymphocytes, primary and secondary lesions of EBVaGC in all cases for which all three tissue types were studied (six of six). There was no correlation between the presence of the 30-bp deletion with depth of cancer invasion or presence of metastasis. Type A was detected in all available EBV-positive cases. The similar high incidence of 30-bp deletion in LMP1 gene in both carcinoma cells and reactive lymphocytes in EBVaGC cases suggests that this deletion may not be relevant to the pathogenesis of EBVaGC.

Nitric oxide donor NOR 3 inhibits ketogenesis from oleate in isolated rat hepatocytes by a cyclic GMP-independent mechanism

Studies were conducted to clarify the effects of nitric oxide donors NOR 3 ((+/-)-(E)-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexeneamide, FK409), SIN-1 (3-morpholinosydnonimine) and SNAP (S-nitroso-N-acetylpenicillamine) on the accumulation of cGMP and cAMP and Ca2+ mobilization as well as ketogenesis from oleate in isolated rat hepatocytes. NOR 3 caused inhibition of ketogenesis from oleate along with stimulation of cGMP accumulation in rat hepatocytes, whereas SIN-1 and SNAP exerted no effect on ketogenesis despite their marked stimulation of cGMP accumulation. Although the nitric oxide trapping agent, carboxy-PTIO (2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide), antagonized the stimulation by NOR 3 of cGMP accumulation, it failed to modulate the anti-ketogenic action of NOR 3. Furthermore, neither 8-bromoguanosine-3',5'-cyclic monophosphate nor N2,2'-O-dibutyrylguanosine-3',5'-cyclic monophosphate mimicked the anti-ketogenic action of NOR 3. It is concluded in the present study that NOR 3-induced inhibition of ketogenesis in rat hepatocytes is not mediated by cGMP. The present study revealed that the remaining structure of NOR 3 from which nitric oxide had been spontaneously released had no anti-ketogenic action. We first and clearly demonstrated that nitrite production was dramatically enhanced when NOR 3 was incubated in the presence of rat hepatocytes. The mechanism whereby NOR 3 inhibits ketogenesis in rat hepatocytes will be discussed.

[Objective assessment of subjective symptom in chronic heart failure]

Objective assessment of subjective symptoms in patients with chronic heart disease (CHF) is useful not only in determining severity and prognosis, but also in evaluating the effects of therapy. Recently anaerobic threshold (AT) was introduced as an objective index for functional capacity. We began by evaluating the AT for assessing functional capacity in patients with CHF, using the cardiopulmonary exercise test. In this study, patients with CHF tended to show low values of VO2 at AT. Furthermore, VO2 at AT was decreased in accordance with the increasing severity of the NYHA classification. These results indicate that VO2 at AT can be used as an objective and reliable index for evaluating the functional capacity in patients with CHF. Decreased functional capacity is a major clinical problem in patients with CHF and is associated with skeletal muscle fatigue and/or dyspnea. Secondly, we observed the oxygenation of both working skeletal and respiratory muscles during exercise, using near-infrared spectroscopy to study the factors contributing to exercise limitation of CHF. In this study, the oxygenation profile of exercising skeletal muscle was similar to that of respiratory muscle, but the former showed anaerobic metabolism at an earlier stage of exercise than the latter. In patients with CHF this phenomenon was more prominent than that in normal subjects. These results indicate that near-infrared spectroscopy might be useful in objective assessment of subjective symptoms, namely skeletal muscle fatigue and dyspnea, in patients with CHF.

A spectrum of mutations induced by crotonaldehyde in shuttle vector plasmids propagated in human cells

A spectrum of crotonaldehyde-induced mutations in the supF gene of the shuttle vector plasmid pMY189 replicated in human fibroblast cells was examined. Base sequence analysis of 104 plasmids with mutations in the supF gene revealed that the majority of the mutations were base substitutions (85%) and the rest were frameshifts (15%). A single base substitution was most frequently found (47%), while 25% had multiple base substitutions and interestingly 13% had tandem (adjacent two) base substitutions. Of the base substitution mutations, 50% were G:C-->T:A transversions and 23% were G:C-->A:T transitions. The mutations were not distributed randomly but were located at several hotspots, most of which were G:C base pairs in 5'-AAGG-3' (or 5'-CCTT-3') sequences. Production of propanodeoxyguanosine adducts may be related to such specificity in the mutation spectrum.

Fast imaging of the second moment using magic echo trains

Approaches are discussed to imaging of the second moment of proton NMR dipolar spectra. Two methods are proposed using the peak shapes of the magic echo trains for evaluation of the second moment. One is a quasi-multidimensional FT approach where the peak shapes of the magic echoes are spatially resolved, and the other is the fast version of the former approach, collecting the same data in a much shorter measurement time. Preliminary results of spatially 2D, as well as 1D, experiments are reported.

Expression, localization and alternative splicing pattern of fibronectin messenger RNA in fibrotic human liver and hepatocellular carcinoma

BACKGROUND/AIMS

Fibronectin is a multifunctional glycoprotein and plays important roles in cell-to-cell or cell-to-matrix interaction. The molecular and functional diversity of fibronectin arises from alternative splicing of pre-mRNA at three variable regions, termed ED-A, ED-B and IIICS. Cellular fibronectin with ED-A and ED-B regions has different biological activities from plasma fibronectin lacking these regions. This study was aimed at investigating the type-specific expression of fibronectin in human liver diseases.

METHODS

Immunohistochemistry with anti-total and anti-cellular fibronectin monoclonal antibodies, in situ hybridization with cDNA probes detecting common and ED-A regions and RT-PCR to amplify each variable region were performed in 35 specimens, including 4 control, 16 chronic hepatitis, 7 liver cirrhosis and 8 hepatocelular carcinoma.

RESULTS

In control liver, there were slight deposits of cellular fibronectin [ED-A(+)fibronectin] in portal areas. In chronic hepatitis, it was strongly deposited at the margin of the fibrously enlarged portal areas where new collagen fibers were formed. Cellular fibronectin was evenly and abundantly accumulated in fibrotic septa in liver cirrhosis, and in fibrotic septa and capsules of tumor nodules in hepatocellular carcinoma. In control liver, cellular fibronectin mRNA was localized in a few hepatocytes and non-parenchymal cells around central veins, and was increased in the same cell populations near fibrously enlarged portal areas as hepatic fibrosis progressed. In hepatocellular carcinoma, it was expressed in most hepatoma cells. Fibronectin mRNA with three variable regions was detectable by RT-PCR in control liver as well as in each disease group.

CONCLUSIONS

The expression of cellular fibronectin was increased in fibrotic human liver and hepatocellular carcinoma. In human liver, both non-parenchymal cells and hepatocytes participated together in cellular fibronectin production. In hepatocellular carcinoma, hepatoma cells were the main producer. Our results indicate that, in human liver, cellular fibronectin may participate in the hepatic fibrogenesis and in the malignant phenotypes of hepatocellular carcinoma.

[A case of pulmonary arteriovenous fistula presenting as multiple brain abscesses after a sustained period without treatment]

A 64-year-old man was admitted to our hospital with multiple brain abscesses accompanied by pulmonary arteriovenous fistula (PAVF). He had been diagnosed with PAVF eight years previously, but had refused any treatment despite a developing exertional dyspnea. Rendu-Osler-Weber disease was diagnosed as well because the patient exhibited teleangiectasis of the nasopharyngeal mucosa and persistent gastro-intestinal bleeding. Despite administration of antibiotics and corticosteroids the abscesses perforated into the lateral ventricle. The natural history of this rare disease is still incompletely understood. Thus, the time at which treatment should be commenced remains unclear. However the natural course of PAVF is unsatisfactory, and it appears that treatment by surgery and/or embolization should be considered in all cases.

Modulation of cytokine production and protection against lethal endotoxemia by the cardiac glycoside ouabain

BACKGROUND

Recent studies have shown that cytokines are capable of modulating cardiovascular function and that some drugs used in the treatment of heart failure variably modulate the production of cytokines. To examine whether cardiac glycosides also modulate cytokine production, we evaluated the effects of ouabain on the production of cytokines in vitro and in vivo.

METHODS AND RESULTS

Human peripheral blood mononuclear cells (PBMC) were obtained from healthy volunteers. PBMC were cultured with or without ouabain in the presence or absence of lipopolysaccharide (LPS). Ouabain induced the production of interleukin (IL)-1beta, IL-6, and tumor necrosis factor (TNF)-alpha in PBMC and induced mRNA of these cytokines, an induction apparently at the transcriptional level. Amiloride, staurosporin, and genistein inhibited cytokine production, and protein kinase C and tyrosine kinase appeared to be involved in the modulation of cytokine production induced by ouabain. However, when PBMC were stimulated with LPS, ouabain suppressed the production of IL-6 and TNF-alpha. To investigate whether ouabain modulates cytokine production in vivo, we evaluated the effects of ouabain in LPS-treated mice. Ouabain was found to protect against LPS-induced lethal toxicity in mice and decreased circulating IL-6 and TNF-alpha levels in vivo.

CONCLUSIONS

These previously unrecognized immunomodulating effects of a cardiac glycoside may explain either the beneficial or the detrimental effects of these drugs in heart failure patients.

A unique response to staphylococcal enterotoxin B by intrahepatic lymphocytes and its relevance to the induction of tolerance in the liver

It has been reported that the intrahepatic lymphocyte (IHL) population is somewhat differently constituted from lymphocytes in other lymphoid tissues. Staphylococcal enterotoxin B (SEB) is a superantigen which can induce T-cell tolerance in mice. The authors investigated the in vitro and in vivo responses of mouse IHL to SEB. An intravenous injection of SEB did not result in the augmentation of the proliferative response of IHL, while mesenteric and splenic lymphocytes (mLNC and SPC, respectively) had augmented responses. Interleukin-2 (IL-2) mRNA was clearly detected in mLNC and SPC by reverse transcriptase-polymerase chain reaction (RT-PCR) shortly after the administration of SEB, but it was scarcely expressed in IHL. The expression of CD25 (IL-2 receptor) was also augmented in mLNC and SPC in the early period, while it was not changed in IHL. These findings suggested that the time required for tolerance induction is different locally and that the loss of augmentation of IL-2 and IL-2 receptor production by IHL may be relevant to the rapid induction of T-cell tolerance in the liver.

Evaluation of prognostic factors following expansive laminoplasty for cervical spinal stenotic myelopathy

BACKGROUND

Expansive laminoplasty of several types has been proposed for patients with cervical multisegmental stenotic myelopathy to reduce postlaminectomy complications. Its effectiveness has not been fully explored by evaluating long-term results and magnetic resonance imaging (MRI) findings before and after surgery.

METHODS

We conducted a 5-year follow-up study of 22 patients with cervical spondylotic myelopathy and/or ossification of the posterior longitudinal ligament surgically treated with expansive laminoplasty. The operative results were examined using the Japanese Orthopedic Association (JOA) disability scale, with reference to the findings of MRI, computed tomography, and radiography.

RESULTS

Postoperative improvement was observed in 18 (81.8%) of the 22 patients. In 11 patients the percentage recovery of the JOA score was higher than 50% (average: 83.1%), while in the remaining 11 patients it was lower than 50% (average: 20.1%). Factors contributing to incomplete recovery appear to be related mainly to cord degeneration with atrophy (depicted as a T2-high intensity area) and to specific factors such as long symptom duration, age higher than 70 years, deterioration due to trauma, severe cord compression, radiculopathy, and kyphotic cervical curvature.

CONCLUSIONS

In cervical myelopathy, patients with multisegmental stenosis, expansive laminoplasty can be expected to provide a favorable outcome by providing sufficient cord decompression and stabilization of the cervical spine, when the stenotic cervical canal is enlarged to the normal range (over 12 mm residual anteroposterior diameter and 200 mm2 residual canal area). The efficacy can be restricted by various factors, especially irreparable cord degeneration.

Augmentation of natural killer cell activity induced by cytomegalovirus infection in mice treated with FK506

Comparable rates of patient and graft survival after FK506 and cyclosporine treatments have been reported in the prevention of liver allograft rejection. On this basis, we examined the effect of FK506 on pathogenesis of cytomegalovirus (CMV) infection in mice. FK506 induced apparent immunosuppression in mice which could be monitored by the level of antibody production. The effective dose of trinitrophenyl-keyhole limpet hemocyanin (TNP-KLH) for 50% reduction in antibody production was 0.9 mg/kg. Even in such an immunosuppressed status at this or higher dose of FK506, CMV infection was relatively alleviated, which was observed by the frequency of virus isolation and the mean virus titer of the lungs of mice treated with 0.1-1 mg/kg FK506 in comparison to untreated mice. The dose of FK506 attaining 50% frequency of lung infection was 1.5 mg/kg. The activity of natural killer (NK) cells was enhanced in infected mice. This enhancement was stronger in infected mice treated with FK506 at 0.32 mg/kg and 10 mg/kg than in untreated infected mice on day 3 post infection (p.i.). Thus, an immunosuppressant FK506 augmented inducible NK cell activity and alleviated MCMV infection even under immunosuppression.

Migration of Gianturco expandable metallic stents in the upper trachea

Endotracheal expandable metallic stents have been shown to be useful in treating malignant tracheobronchial stenosis. We report two cases of early stent migration in the upper trachea after what appeared to be a successful stent placement. We conclude that care should be taken when placing Gianturco stents across short, extrinsic, stenotic lesions with smooth mucosa located in the upper trachea because they have a tendency to migrate.

Effects of extracellular ATP on cytosolic Ca2+ concentration and secretory responses in rat parotid acinar cells

At concentrations >50 microM, extracellular ATP dose-dependently increased cytosolic Ca2+ concentration ([Ca2+]i) via activation of P(2Z) purinoceptors in rat parotid acinar cells. This increase in [Ca2+]i is primarily due to entry of Ca2+ from the extracellular medium. Inositol trisphosphate formation and Ca2+ release from intracellular Ca2+ stores were slightly stimulated by ATP. These responses seem to result from the activation of a P2 purinoceptor subtype different from P(2Z) because the maximum responses were induced by much lower concentrations ( <0.25 mM) of ATP than those (> 1 mM) required to produce the maximum activation of Ca2+ entry. ATP did not stimulate amylase release, supporting the view that an increase in [Ca2+]i is not a sufficient stimulus. In addition, ATP evoked a marked K+ release in the presence and absence of extracellular Ca2+, while in carbachol-stimulated cells. only a transient release of K+ was observed in the absence of extracellular Ca2+. The ATP-induced K+ release may be mediated by a mechanism independent of the opening of the Ca(2+)-sensitive K+ channels.

Appraisal of combination treatment for hepatocellular carcinoma: long-term follow-up and lipiodol-percutaneous ethanol injection therapy

Since 1988, 124 patients with hepatocellular carcinoma were treated in our departments. Among them, 31 cases treated by surgical resection and 30 cases administered a combination therapy (Lipiodol [Laboratoire Guerbet, Villepinte, France]-transcatheter arterial embolization [L-TAE] and lipiodol-percutaneous ethanol injection therapy [L-PEIT]) were analyzed retrospectively. The 1-, 3-, and 5-year survival rates were, respectively, 89.0%, 72.7%, and 63.6% for the surgical resection group and 93.3%, 72.8%, and 42.0% for the combination therapy group. The follow-up results at less than 4 years after the procedures revealed that the survival rate with the combination therapy was slightly better than that with the surgical treatment. However, in the subsequent 4 years, the survival rate of the combination therapy group decreased rapidly. The reasons for this deterioration were local recurrence and/or new primary lesions of hepatocellular carcinoma, mainly due to inappropriate ethanol injection. To achieve adequate and accurate injection of ethanol, a 10% volume of Lipiodol was mixed with the ethanol so that the location of the injected ethanol could be easily confirmed. The effectiveness of L-PEIT was thus confirmed by computed tomography, performed on the following day. Defective Lipiodol accumulation in the tumor and/ or neighboring tissues was able to be corrected by additional ethanol injections. With this L-PEIT technique, the tumor necrosis rate is now improving. Therefore, a better prognosis is expected.

Peptides derived from cardiovascular G-protein-coupled receptors induce morphological cardiomyopathic changes in immunized rabbits

An experimental model of early-stage cardiomyopathy was created by immunizing rabbits for 1 year with synthetic peptides corresponding to the sequence of the second extracellular loop of either beta-adrenoceptors or M2-muscarinic receptors. Thirty male rabbits were used and divided into three groups: a control group (n = 10), a group immunized with the peptide corresponding to the beta-adrenoceptor (beta 1 group) (n = 10) and a group immunized with the peptide corresponding to the M2-muscarinic receptor (M2 group) (n = 10). If the sera from both groups of immunized rabbits high-titres of anti-peptide antibodies were found throughout the study period but not in the sera from control rabbits or in the preimmune sera of immunized rabbits. No significant cross-reaction with peptides other than those used for immunization was found. The myocardial receptor density of both immunized groups displayed a strong trend toward receptor up-regulation. This was significant in the beta 1 group but not in the M2 group. Both groups of immunized rabbits displayed significantly enlarged ventricles and thinner walls, as compared with the control group. However, in contrast to the beta 1 group, which showed enlarged cavities in both left and right ventricles, the M2 group was mainly affected in the right ventricles. Moreover, morphological examinations of the hearts of rabbits from both immunized groups demonstrated focal myofibrillar lysis, loss of myofilament, mitochondrial swelling and condensation, sarcoplasmic vacuolation, deposition of dense granules in the sarcoplasm and the myofibrils. One of the sex control rabbit hearts which were examined showed mild degenerative changes in the myocardium and scant mononuclear cell infiltration. However, when all the control rabbit hearts were examined by electron microscopy, no significant alterations were found. These results suggest that immunization by peptides, corresponding to the target sequences for anti-receptor autoantibodies in idiopathic dilated cardiomyopathy, induces morphological changes in the heart similar to those found in the human disease.

Beneficial effects of amlodipine in a murine model of congestive heart failure induced by viral myocarditis. A possible mechanism through inhibition of nitric oxide production

BACKGROUND

Although calcium channel blockers have not been shown to be beneficial for the treatment of patients with heart failure, a recent clinical trial demonstrated a favorable effect of amlodipine on the survival of patients with heart failure resulting from nonischemic dilated cardiomyopathy. We investigated the effects of amlodipine on a murine model of congestive heart failure induced by the M variant of encephalomyocarditis virus (EMCV).

METHODS AND RESULTS

Four-week-old male DBA/2 mice were inoculated with EMCV and administered amlodipine, diltiazem, or vehicle PO for 2 weeks. The heart weight-to-body weight ratio and the histopathological grades of myocardial lesions were significantly lower and survival was significantly increased in the amlodipine-treated group (P < .01, P < .05, and P < .05, respectively) than in the control group. In vitro, amlodipine added to murine J774A.1 macrophages concomitant with EMCV inhibited nitrite formation in a concentration-dependent manner, but diltiazem did not. Furthermore, NG-monomethyl-L-arginine, an inhibitor of NO synthesis, decreased myocardial lesions significantly in this murine model. Immunohistochemistry revealed that the number of cells stained with antibody against an inducible NO synthase decreased significantly in the amlodipine-treated group compared with that in the control group (P < .01).

CONCLUSIONS

Amlodipine appears to have a protective effect against myocardial injury in this animal model of congestive heart failure. The therapeutic effect of amlodipine may be in part resulting from inhibition of overproduction of NO.

Prolongation of murine cardiac allograft survival with vesnarinone

Vesnarinone is a non-glycoside positive inotropic drug that has immunomodulating actions. In the present study, the effects of vesnarinone on both cardiac allografts and lymphocytes were investigated. First, in a mouse model of primary vascularized heterotopic cardiac transplantation, the oral vesnarinone treatment at a dose of 50 mg/kg/day prolonged median graft survival time significantly as compared with the vehicle-treated control. Histopathological examination revealed that cellular infiltration and interstitial edema were less prominent in the vesnarinone-treated than in the vehicle-treated allografts. The plasma concentrations of vesnarinone in mice treated with a single dose of 50 mg/kg were within the range of clinical relevance. To clarify the mechanism of action, in vitro studies were performed. The generation of specific cytotoxic T lymphocytes in mixed lymphocyte culture was significantly suppressed by the treatment with vesnarinone, especially at 3 and 10 microg/ml. The production of interferon-gamma in the co-culture was also suppressed by 10 microg/ml vesnarinone. However, the level of cyclic adenosine monophosphate was not significantly affected by vesnarinone at 10 microg/ml. The results suggest that vesnarinone acts beneficially on rejecting cardiac allografts through its lymphocyte-suppressive property, although this property may not be closely associated with the inhibiting action of the drug on the cyclic adenosine monophosphate-phosphodiesterase enzyme.

Airway epithelial cells produce stem cell factor

Airway epithelial cells modulate the inflammatory response in asthmatic, allergic and fibrotic lung diseases through the secretion of cytokines that regulate the movement and activation of inflammatory cells. Mast cells play an important role in the pathogenesis of these lung diseases. In this study we report that normal airway epithelial cells express stem cell factor which is a critical mediator of mast cell growth and differentiation and that transforming growth factor-beta inhibits secretion of stem cell factor by airway epithelial cells.

[In situ detection of Epstein-Barr virus in the non-neoplastic gastric glands and infiltrated lymphocytes]

Recently, clonal EBV-DNA and/or EBV-encoded small RNA(EBER1) have been detected in some gastric carcinomas. We reported the first observation of EBV infection in gastric glands with intestinal metaplasia, and characterized the EBV-infected lymphocytes which infiltrated in gastric mucosa. To determine the cellular location of EBV, EBER1 in situ hybridization(ISH) with an EBER1 oligonucleotide probe was applied to paraffin sections of the non-neoplastic gastric mucosa in 80 cases of gastric carcinoma and 49 cases of gastric ulcer. Not only was EBER1 expression detected in the nucleus of gastric cancer cells(5 cases) but also in non-neoplastic gastric epithelial cells(3 cases) and in infiltrated lymphocytes(40 cases). A single or a few shedding non-neoplastic epithelial cells in 2 cases of EBV-associated gastric cancer showed EBER1 expression. In one case, EBER1 was observed in all of the epithelial cells of a few gastric glands with intestinal metaplasia, suggesting that the stem cells of the metaplastic gastric glands were infected with EBV. EBV DNA was also detected in the EBER1-positive metaplastic glands scratched from the paraffin section by a single cell PCR method with a BamHI W primer pair. However, immunohistochemical examination showed that these metaplastic glands lacked expression of EBNA2 and LMP-1. The observation of these rare EBV-infected metaplastic glands reinforces the pre-transformation EBV infection hypothesis for EBV-associated gastric carcinoma. The double staining using ISH and immunohistochemistry revealed that EBER1 positive lymphocytes showed a B cell marker of L26(< 50%) but not T cell markers of UCHL1 and OPD4.

Immunomodulation: a new horizon for medical treatment of heart failure

Recently, the intriguing possibility has been raised that heart failure may be mediated by the biological effects of cytokines. Indeed, we found elevation of plasma concentrations of various cytokines in patients with myocardial disease. We also detected positive tumor necrosis factor (TNF-alpha) immunoreactivity in right atrial tissues obtained during surgery from patients with severe heart failure. Therefore, we postulated that some aspects of heart failure may be related to non-lethal down-modulation of cardiac function by immune cells and their cytokines. Testing this hypothesis in an experimental model of murine myocarditis, we found that injection of recombinant human TNF-alpha increased mortality of the animals infected with myocarditis virus. The anti-TNF-alpha monoclonal antibody improved survival and attenuated the myocardial lesions. Whereas, administration of recombinant human IL-2 in the acute viremic stage increased survival rate, and resulted in less intense pathological changes in the myocardium while in the subacute aviremic stage, the same amount of IL-2 reduced survival rate and exacerbated severity of the disease. Therefore, cytokine release may initiate a beneficial inflammatory and immune response in the acute phase of the disease process, but the continued induction of cytokines and the enhanced natural killer (NK) cell activity in the later stage are no longer protective. Vesnarinone, a recently synthesized inotropic agent which has proved to benefit patients with congestive heart failure by improving prognosis, also increased the survival of individual subjects in the above-mentioned murine model of heart failure. Cytotoxicity of NK cells obtained from the virus infected animals was substantially reduced when treated with vesnarinone. Vesnarinone also inhibited production of TNF-alpha and other cytokines from stimulated human lymphocytes and cultured murine splenocytes. We conclude, therefore, that inhibition of NK cell activity and suppression of cytokine production appear to be important immunological defense mechanisms which could contribute to the observed salutary effects of vesnarinone in the treatment of chronic heart failure. More broadly, immunomodulation could pave the way for a new frontier in the management of heart failure.

Tetrahydrobiopterin biosynthesis enhanced by lipopolysaccharide stimulation in murine neuroblastoma cell line N1E-115

We investigated for the first time the effect of lipopolysaccharide and the signal transduction pathway on the biosynthesis of tetrahydrobiopterin [(6R-L-erythro-1',2'-dihydroxypropyl) -2-amino-4-hydroxy-5,6,7,8-tetrahydropteridine], the cofactor for the enzymatic hydroxylation of the aromatic amino acids, in the murine neuroblastoma cell line N1E-115, which synthesizes tetrahydrobiopterin constitutively. Activation of N1E-115 cells with 1 microgram/ml lipopolysaccharide resulted in statistically significant increases in both intracellular tetrahydrobiopterin contents and the activity (Vmax) of GTP cyclohydrolase I, a rate-limiting enzyme in tetrahydrobiopterin de novo biosynthesis. Following simultaneous addition of the inhibitors of protein tyrosine kinases and GTP-binding proteins into serum-free culture media with lipopolysaccharide, we analyzed the transduction pathway of lipopolysaccharide signal toward the tetrahydrobiopterin biosynthetic system in N1E-115 cells. Our data indicate the following conclusions: (a) Protein tyrosine kinase systems are involved in mediating lipopoly-saccharide signal to tetrahydrobiopterin production, and (b) there may be a cross-talk between GTP-binding protein and the protein tyrosine kinase system in mediating lipopolysaccharide signal. These observations suggest that a neuronal cell such as N1E-115, which barely expresses CD14 on its cell surface, responds to lipopolysaccharide like macrophages and monocytes in the absence of soluble CD14.

Primary human fibroblasts induce diverse tumor invasiveness: involvement of HGF as an important paracrine factor

Fibroblasts have been considered to play an important role in tumor progression. In order to evaluate the contribution of fibroblasts to tumor invasion, TE2-NS, an esophageal cancer cell line, was cultured on collagen gel containing primary fibroblasts derived from normal esophageal submucosa or cancerous tissues of seven esophageal cancer patients. TE2-NS showed diverse invasiveness into the underlying gel containing fibroblasts, but did not invade the gel not containing fibroblasts. The invasiveness of TE2-NS, which expressed hepatocyte growth factor (HGF) receptor, was well-correlated with the concentration of HGF in conditioned medium. Administration of neutralizing antibody against HGF effectively suppressed the invasion, but application of recombinant HGF without fibroblasts induced little invasion into the gel. Fibroblasts from non-cancerous tissue generally secreted a larger amount of HGF and induced tumor invasion to a greater extent than those from cancer tissue, with large diversity. Interestingly, HGF secretion of fibroblasts from non-cancerous tissue was stimulated by co-culture with TE2-NS in two lines, but not in the other four. These results indicate that HGF is an important paracrine factor which induces tumor cell invasion, and the diversity of HGF production by fibroblasts might suggest different potentiality to induce tumor invasion among patients.

Decreased E-cadherin expression is associated with haematogenous recurrence and poor prognosis in patients with squamous cell carcinoma of the oesophagus

Reduced expression of E-cadherin is associated with tumour invasiveness and metastasis. To elucidate whether E-cadherin expression correlates with clinical outcome in patients with oesophageal cancer, 62 patients were investigated immunohistochemically using an anti-E-cadherin monoclonal antibody (HECD-1). Eight patients had normal levels of expression in the tumour, 25 had tumours that expressed high levels (50 per cent or more tumour cells staining positive for E-cadherin) and 29 had tumours expressing low levels (less than 50 per cent of cells expressing E-cadherin). Patients with normally expressing tumours had a better prognosis at 3 years than those with low-expressing tumours (P < 0.05). Postoperative death was correlated significantly with lymphatic invasion, lymph node metastasis, E-cadherin expression and depth of invasion (P < 0.05). Furthermore, haematogenous recurrence was correlated with E-cadherin expression (rs = 0.38, P < 0.01) and blood vessel invasion (rs = 0.28, P < 0.05). These results suggest that evaluation of E-cadherin immunoreactivity may predict haematogenous recurrence and poor prognosis in patients with oesophageal cancer.

[Intra-arterial infusion chemotherapy for liver metastases from breast cancer]

Twelve patients with liver metastases of breast cancer were treated with hepatic arterial infusion chemotherapy using 20-30 mg/body of epi-adriamycin (epi-ADM) every 2 weeks and continuous infusion of 250 mg/body/day of 5-fluorouracil (5-FU). All patients were followed by systemic chemo-endocrine therapy with oral administration of 600-1,200 mg/day of me droxyprogesterone acetate (MPA) alone or with 600-800 mg/day of 5'-deoxy-5-flurouridine (5'-DFUR). The response rate was 41.7% (5/12 cases). Duration of response was 2-28 months (mean 10 months). At one year, the survival rate was 46.8% (Kaplan-Meier method). As for side effects, gastrointestinal disturbance, bone marrow depression and alopecia were mild. These results suggest that hepatic arterial infusion therapy in combination with MPA is safe and effective for controlling liver metastases of breast cancer.

Use of chloride blockers: a novel approach for cardioprotection against ischemia-reperfusion damage

We examined whether the chloride channel blockers anthracene-9-carboxylic acid (9-AC) and 4-acetamide-4'-isothiocyanatostilbene-2,2'-disulfonic acid (SITS) exert protective effects against myocardial ischemia-reperfusion damage. In isolated guinea pig ventricular cells, 9-AC (200 microM), but not SITS (100 microM), inhibited the chloride current induced by isoproterenol. Electrical and mechanical activities and intracellular pH of arterially perfused guinea pig right ventricular preparations were recorded with an intracellular microelectrode, a force transducer and a pH-sensitive fluorescent probe, respectively. The preparations were subjected to 30 min of no-flow ischemia, with or without 9-AC (100 microM) or SITS (10 microM), followed by reperfusion. No-flow ischemia produced decreases in action potential amplitude and duration, and the contractile force was completely abolished. Although the changes in electrical parameters were reversed upon reperfusion, the contractile force recovered only to about 50% of preischemic values. 9-AC and SITS had no inhibitory effect on contractile force under normal conditions and during ischemia but significantly improved the recovery of contractile force upon reperfusion to about 80% of preischemic values. Both 9-AC and SITS showed significant inhibition of the ischemia-induced abbreviation of action potential duration. Other parameters were not affected by 9-AC or SITS. During ischemia, intracellular pH showed a transient small increase followed by a sustained decrease, which was completely recovered upon reperfusion. The decrease in pH during ischemia was attenuated by 80% in SITS- but not 9-AC-treated preparations. Thus, we demonstrated that the chloride channel blockers 9-AC and SITS, which have no cardiosuppressive effects, exert protective effects against myocardial ischemia-reperfusion damage.

Characteristic distribution of circulating autoantibodies against G-protein coupled cardiovascular receptors in patients with idiopathic dilated and hypertrophic cardiomyopathy

Circulating autoantibodies against cardiovascular membrane receptors have been repeatedly demonstrated in a subgroup of sera of patients with idiopathic dilated cardiomyopathy. This short review summarizes the clinical findings on anti-receptor autoantibodies in patients with dilated cardiomyopathy.

[Brain CT and MRI findings in fat embolism syndrome]

To elucidate brain CT and MRI findings in fat embolism syndrome (FES), we retrospectively analyzed images from 5 patients with FES during the acute and subacute stages. Brain CT examinations demonstrated brain edema in 2 patients and transient spotty low density lesions in 2 patients. Three patients showed no abnormalities. Brain MRI, however, showed brain abnormalities in all patients during the acute stages. These were revealed as spotty high signal intensity lesions on T2WI, and some showed low intensity on T1WI. These spotty lesions were considered to reflect edematous fluid occurring as a result of the unique pathophysiological condition of FES. While the spotty high signal intensity lesions on T2WI were distributed in the cerebrum, cerebellum, brain stem, thalamus, basal ganglia, internal capsule and corpus callosum, cerebral and cerebellar spotty lesions were characteristically located along the boundary zones of the major vascular territories. This characteristic location might be induced by a hypoxic brain condition in FES because the numerous fat globules present in this condition can block entire brain capillaries. This characteristic signal location on T2WI is a useful indicator for differentiating FES from the primary intra-axial brain injury in patients with multifocal trauma.

Immunomodulation by an adenylate cyclase activator, NKH477, in vivo and vitro

Cyclic adenosine monophosphate (cAMP) is an intracellular second messenger which modulates T cell function. NKH477 is a direct adenylate cyclase activator derived from forskolin and now under clinical investigation as a positive inotropic agent. While the immunosuppressive effects of forskolin on lymphocytes have been reported, little is known about its effects in vivo. In this study, we investigated whether NKH477 has immunosuppressive effects in mice, namely on cardiac allograft survival, and on the generation of cytotoxic T lymphocytes (CTL), T cell proliferation in mixed lymphocyte reaction (MLR), and production of interleukin-2 (IL-2) in MLR and in mitogen response. We assessed the effects of standard immunosuppressant cyclosporin A (CsA) on IL-2 production and on allograft survival to estimate the intensity of rejection in this acute rejection model. Saline-treated C57BL/6 (H-2b) mice rejected DBA/2 (H-2d) cardiac allografts with a median graft survival time of 10 days. In contrast, median graft survival was prolonged to 12 and 15 days in mice treated with NKH477 at 1 and 3 mg/kg/day, respectively (P < 0.01 vs control). The equivalent dose of CsA (40 mg/kg/day) to the maintenance dose after clinical cardiac transplantation prolonged median graft survival time to 15.5 days, indicating that high dose of NKH477 was as efficacious as lower dose of CsA. Addition of NKH477 to the culture medium suppressed the generation of CTL, T cell proliferation in MLR, and production of IL-2 in MLR and in mitogen response. These results suggest that NKH477 exerts a beneficial effect on murine cardiac allograft survival by modulating T cell function.

[Stage IIIa endometrial carcinoma: MR findings]

[PURPOSE]: An attempt was made to evaluate the ability of magnetic resonance (MR) imaging to diagnose stage IIIa endometrial carcinoma. [MATERIALS AND METHODS]: Thirty-three patients with endometrial carcinoma underwent MR imaging and surgery. Surgical staging was classified as I in 21 patients, II in 3 patients and III in 9 patients. The MR images of each patient were retrospectively reviewed by three radiologists. Only the clinical diagnosis of endometrial carcinoma was previously notified. Segmental disruption of the full thickness of the myometrium was considered serosal invasion. Intraperitoneal metastasis was diagnosed according to three criteria (intraperitoneal solid mass of isointensity compared with endometrial lesion, cystic mass excluding benign ovarian cysts, ascites). These evaluations were compared with the surgical findings and analyzed by the kappa statistic. [RESULTS]: The rates of sensitivity and positive predictive value (PPV) for serosal invasion were 33% and 6%, respectively. False positive evaluation frequently occurred when thickness of the intact myometrium was less than 5mm. The rates of sensitivity and PPV for intraperitoneal metastasis were 86% and 72%, respectively. The reason for false negative evaluation was small foci of intraperitoneal metastasis. Overall, sensitivity and PPV for stage IIIa were 86% and 69%, respectively. [CONCLUSION]: MRI was useful in detecting intraperitoneal metastasis of endometrial carcinoma with the exception of diagnosing serosal invasion. It is difficult to detect small foci of peritoneal metastasis. It is necessary to differentiate adnexal metastasis from benign adnexal masses.

Preparation of an activity-inhibiting monoclonal antibody against human placental aromatase cytochrome P450

We produced a murine monoclonal antibody (MAb) to human placental aromatase cytochrome P450. This MAb, designated MAb3-2C2, was selected on its ability to suppress aromatase activity. The specificity of this MAb was assessed by selective immunoprecipitation of 125I-labeled aromatase cytochrome P450 as well as by the identification of a 55-kDa protein, which was enriched and purified by immunoaffinity chromatography on a MAb-coupled Sepharose 4B column. The MAb was able to suppress both human placental and ovarian microsomal aromatase. Species differences of aromatase were recognized by MAb3-2C2 on the basis of differential immunosuppression of aromatase activity. The antibody had no effect on non-aromatase cytochrome P450s. MAb3-2C2 gave negative results with human placental aromatase P450 in the Western blot analysis. The data presented indicate that MAb3-2C2 is specific for aromatase cytochrome P450 and that its epitope is located in a fragile tertiary conformation of the enzyme, thus making it capable of sensitively affecting catalysis.

Characteristic immunological tolerance in intrahepatic lymphocytes induced by bacterial superantigen SEB

We have reported that the liver is closely associated with the hematolymphoid system and that the liver, as a lymphoid organ, may play an important role in the differentiation of lymphocytes and oral tolerance. To investigate the relevance of the liver to immunological tolerance, we compared the response pattern to Staphylococcus enterotoxin B (SEB) in intrahepatic lymphocytes (IHL) with those of spleen cells (SPC) and mesenteric lymph node cells (mLNC) during tolerance induction. Tolerance was induced by i.v. injections of SEB in all three organs. IHL had a distinct pattern from the other cells in the induction of unresponsiveness to SEB. While SPC and mLNC have a proliferation phase before the reduction of DNA synthesis, IHL become tolerant immediately without this phase. When IHL became tolerant in the early period after SEB injection, their nylon-wool column non-adherent (NW-NA) IHL were not recovered from unresponsiveness in vitro in spite of the addition of irradiated normal SPC as accessory cells. NW-NA IHL did not secrete IL-2 during this process, indicating that NW-NA IHL were in a state of functional anergy soon after the i.v. administration of SEB. Phenotypic analysis revealed that the characteristic changes of IHL during the induction of unresponsiveness might be associated with the kinetic modulation of CD4+ V beta 8+ T cells. These results suggest that the liver may hold a different mechanism for the induction of tolerance to SEB from that of SPC and mLNC.

Metabolic effects of glibenclamide in isolated rat hepatocytes in the absence of extracellular Ca2+

We examined the metabolic effects of glibenclamide, a potent second-generation sulfonylurea, in isolated rat hepatocytes incubated in the absence of extracellular Ca2+. We first demonstrated in the present study that glibenclamide caused a significant increase in basal glucose release and lactate production without any modification of intracellular Ca2+ concentration or cAMP levels in isolated rat hepatocytes. Furthermore, glibenclamide inhibited the noradrenaline-induced increase in cAMP accumulation, while activation of glycogenolysis by noradrenaline was not suppressed by this agent. Our data indicate that glibenclamide exerts its metabolic effects independent of intracellular Ca2+ mobilization and cAMP accumulation.

Molecular analysis of mutations induced by 2-chloroacetaldehyde, the ultimate carcinogenic form of vinyl chloride, in human cells using shuttle vectors

Vinyl chloride (VC) is a carcinogen associated with human and animal cancers. The ultimate carcinogenic form of VC, 2-chloroacetaldehyde (CAA), has been suspected to be mutagenic and we confirmed the mutagenicity of CAA using a modified shuttle vector plasmid. Base sequence analyses of 109 mutant plasmids with mutations in the supF gene, which were treated with CAA and propagated in the cultured human cells, revealed that more than half of the single base substitutions were G:C to A:T transitions with eight hotspots. The majority of the mutations involving G:C base pairs were in 5'-AAGG-3' or 5'-CCTT-3' sequences suggesting that these sequences are the main targets of mutagenesis caused by CAA.

Beneficial effect of amrinone on murine cardiac allograft survival

Amrinone is a non-glycoside positive inotropic agent with an inhibitory effect on a cyclic adenosine monophosphate (AMP) phosphodiesterase isoenzyme. In the present study, we examined the immunosuppressive action of amrinone, since several other cyclic AMP-elevating agents have been shown to suppress T lymphocyte activation. First, the in vivo effects of amrinone were investigated. Oral amrinone treatment, at 40 mg/kg per day, significantly prolonged median cardiac allograft survival compared with non-treated controls (22.0 days versus 10.5 days, P < 0.01) when DBA/2 mouse hearts (H-2d) were heterotopically transplanted into C57B1/6 mice (H-2b). Histopathological examination showed that there was less prominent cellular infiltration in the amrinone-treated than in the non-treated allografts. Plasma amrinone concentrations of mice after a single oral dose of 40 mg/kg were within the range of clinical relevance. To clarify the mechanism of action, in vitro studies were done. The generation of specific cytotoxic T lymphocytes after mixed lymphocyte culture was significantly suppressed by addition of amrinone to the culture medium at 5 micrograms/ml. The production of IL-2 and the interferon-gamma during mixed lymphocyte culture was also suppressed by amrinone at 5 micrograms/ml. However, the level of intracellular cyclic AMP in mouse splenic lymphocytes was not affected significantly by the same dose of amrinone. In conclusion, amrinone has immunosuppressive actions at the therapeutic doses, and it may be a beneficial agent for therapy against acute cardiac allograft rejection.

[Histopathological and immunohistochemical evaluation of lymph node metastasis in superficial esophageal cancer--with reference to the expression of E-cadherin and alpha-catenin]

We compared node-negative patients (13 cases) with node-positive patients (17 cases) with submucosal cancer of the esophagus, to assess the relationship between clinicopathological factors and lymph node metastasis. We also investigated the expression of E-cadherin, an intercellular adhesion molecule (27 cases), and alpha-catenin, an undercoat protein of adherence junction (16 cases) by immunohistochemical staining to evaluate the association between intercellular adhesiveness and lymph node metastasis in superficial esophageal cancer. There was no significant difference between the node-negative and node-positive groups in other clinicopathological factors and tumor size, while the frequency of lymphatic invasion in the node-positive group was statistically higher than that in the node-negative group (p < 0.05). The frequency of lymph node metastasis in 14 cases with preserved expression of E-cadherin was significantly lower than that in 13 cases with reduced or negative expression (7.1% vs. 46.2%: p < 0.05). Moreover, all three patients with negative expression of alpha-catenin had lymph node metastasis, while only one of 13 patients with preserved or reduced expression of alpha-catenin had lymph node metastasis (100% vs. 7.7%: p < 0.01). In conclusion, we have found that the evaluation of both E-cadherin and alpha-catenin expression might be of great value in predicting lymph node metastasis in superficial esophageal cancer.