Angiotensin converting enzyme inhibitors, left ventricular hypertrophy and fibrosis

From pharmacological investigations and clinical studies, it is known that angiotensin converting enzyme (ACE) inhibitors exhibit additional local actions, which are not related to hemodynamic changes and which cannot be explained only by interference with the renin angiotensin system (RAS) by means of an inhibition of angiotensin II (ANG II) formation. Since ACE is identical to kininase II, which inactivates the nonapeptide bradykinin (BK) and related kinins, potentiation of kinins might be responsible for these additional effects of ACE inhibitors. a) In rats made hypertensive by aortic banding, the effect of ramipril in left ventricular hypertrophy (LVH) was investigated. Ramipril in the antihypertensive dose of 1 mg/kg/day for 6 weeks prevented the increase in blood pressure and the development of LVH. The low dose of ramipril (10 micrograms/kg/day for 6 weeks) had no effect on the increase in blood pressure or on plasma ACE activity but also prevented LVH after aortic banding. The antihypertrophic effect of the higher and lower doses of ramipril, as well as the antihypertensive action of the higher dose of ramipril, was abolished by coadministration of the kinin receptor antagonist icatibant. In the regression study the antihypertrophic actions of ramipril were not blocked by the kinin receptor antagonist. Chronic administration of BK had similar beneficial effects in a prevention study which were abolished by icatibant and NG-nitro-L-arginine (L-NNA). In a one year study the high and low dose of ramipril prevented LVH and fibrosis. Ramipril had an early direct effect in hypertensive rats on the mRNA expression for myocardial collagen I and III, unrelated to its blood pressure lowering effect.(ABSTRACT TRUNCATED AT 250 WORDS)

Extracellular matrix deposition in hypertensive hearts antifibrotic effects of ramipril

Hypertension induced in rats by suprarenal banding has a blood pressure elevating effect that is accompanied by the occurrence of cardiac hypertrophy and fibrosis. This phenomenon is already present at 2 weeks after banding and persists up to 1.5 years. The increase in cardiac weight is mostly due to the development of fibrosis, since myocytes are only slightly increased in size. The fibrotic tissue consists mainly of fibronectin and collagen and contains numerous cellular elements. The occurrence of fibrosis can be completely inhibited by the administration of the specific ACE inhibiting drug, ramipril, which indicated that angiotensin II may directly stimulate fibroblasts to produce fibronectin and collagen. The antifibrotic effect of ramipril was also present in a low dosage that did not lower blood pressure, confirming the hypothesis that angiotensin II has a direct effect on connective tissue cells and their ability to produce extracellular matrix proteins. The direct effect of the renin-angiotensin system on the activity of interstitial cells was further proven by molecular biology techniques showing an upregulation of transcription for collagen I and III which is prevented by ACE inhibition.

Soluble thrombomodulin purified from human urine exhibits a potent anticoagulant effect in vitro and in vivo

We examined the anticoagulant activity of two major molecules of soluble thrombomodulin purified from human urine. The apparent molecular weights of these urinary thrombomodulins (UTMs) were 72,000 and 79,000, respectively. Both UTMs showed more potent cofactor activity for protein C activation [specific activity > 5,000 thrombomodulin units (TMU)/mg] than human placental thrombomodulin (2,180 TMU/mg) and rabbit lung thrombomodulin (1,980 TMU/mg). The UTMs prolonged thrombin-induced fibrinogen clotting time (> 1 TMU /ml), APTT (> 5 TMU/ml), TT (> 5 TMU/ml) and PT (> 40 TMU/ ml) in a dose-dependent fashion. These effects appeared in the concentration range of soluble thrombomodulins present in human plasma and urine. In the rat DIC model induced by thromboplastin, administration of UTMs by infusion (300-3,000 TMU/kg) restored the hematological abnormalities derived from DIC in a dose-dependent fashion. These results demonstrate that UTMs exhibit potent anticoagulant and antithrombotic activities, and could play a physiologically important role in microcirculation.

[A case of hemophagocytic syndrome manifesting adult Still's disease and acute hepatitis]

We report a 20 year-old woman with hemophagocytic syndrome. In February 1993, she developed high fever, arthralgia, salmon-like pink eruption, leukocytosis and splenomegaly. She was diagnosed as adult Still's disease and successfully treated with intravenous immunoglobulin and oral prednisolone. In September 1993, she was re-admitted to our hospital complaining of general fatigue and low grade fever and treated with oral prednisolone at a daily dose of 15 mg. On October 2, 1993, she suddenly developed high fever and salmon-like pink eruption on her leg followed by the marked increase of serum transaminase and LDH levels (GOT 3,270 IU/l, GPT 1,880 IU/l, LDH 5,480 IU/l) on October 7. Since hepatic failure progressed, we started methylprednisolone pulse therapy and plasmapheresis. However, because of the progression of pancytopenia caused by hemophagocytosis, the treatment with VP-16 was initiated. However, she died of DIC on November 2, 1993. Autopsy revealed submassive necrosis of the hepatocytes with moderate infiltration of histiocytes. She was retrospectively diagnosed as hemophagocytic syndrome whose manifestations are very similar to those in adult Still's disease and acute viral hepatitis.

Transport mechanism of anthracycline derivatives in rat polymorphonuclear leukocytes: effect of sodium fluoride on pirarubicin uptake

We previously revealed that pirarubicin (THP) was actively taken up by rat polymorphonuclear leukocytes via a carrier-mediated transport system. In the experiment on the effects of the metabolic inhibitors, rotenone, 2,4-dinitrophenol and sodium cyanide significantly decreased the THP transport. However, sodium fluoride (NaF) significantly increased the uptake, and this result is different from that in some reports. Therefore, we examined the action of NaF on THP uptake by the leukocytes to clarify the discrepancy in the effect of NaF on drug transport. The accelerating effect of 30 mM NaF on the THP uptake by the cells had an optimum period of action (15-20 min), and was concentration-dependent (5-30 mM). Thirty mM potassium fluoride, as well as NaF, increased the uptake amount. On the other hand, NaF (5-30 mM) dose-dependently decreased the ATP content in these cells. Additionally, the viable cells in the reaction suspension decreased by about 40% after incubation with 30 mM NaF for 15 min. Observing these leukocytes treated with NaF by optical microscopy, swelling of the cell and an alteration of the nuclei form occurred. On the basis of these results, we speculated that the increased THP transport in polymorphonuclear leukocytes by NaF, probably F-, might be due, at least in part, to an alteration of the morphological form.

Larval anisakid nematodes of Japanese common squid (Todarodes pacificus) from the Sea of Japan

Two species of third-stage larvae of the family Anisakidae are described from the Japanese common squid (Todarodes pacificus Steenstrup) from the Sea of Japan. The larvae of 1 of them, Anisakis simplex (Rudolphi, 1809), commonly occur encapsulated in the viscera of squid, whereas those of another 1, identified as Lappetascaris sp., are found free in the mantle musculature. The latter, characterized by the presence of a very long ventricular appendix, a conspicuous esophageal gland, and the structure of the cephalic end (presence of sclerotized supports of lip anlagen), previously were reported by various authors as members of the genera Contracaecum, Thynnascaris, or Hysterothylacium. It appears that the larvae form the mantle of squid belong to a hitherto undescribed Lappetascaris species whose adults parasitize an, as yet unknown, predatory marine fish.

[A young woman with rheumatoid arthritis who rapidly developed secondary amyloidosis]

A 22-year-old woman, who had been diagnosed as having rheumatoid arthritis (RA) 2 years before, was admitted to our hospital complaining of watery diarrhea (several times/day). She had been treated with low dose prednisolone (PSL) and auranofin in out-patient clinic. On admission, laboratory data showed moderate proteinuria (0.3 g/day) and positive CRP (2.7 mg/dl). Although the activity of RA was controlled by the administration of low dose methotrexate (7.5 mg/week) in addition to PSL, watery diarrhea and proteinuria did not improve. The biopsy of the stomach, rectum and kidney revealed the deposition of AA type amyloid protein, resulting in the diagnosis of secondary amyloidosis. Secondary amyloidosis has been reported as one of the common complications in RA patients, especially in old patients with a long history of RA. To our knowledge, however, there have been few reported cases who developed secondary amyloidosis so early during the course of RA as our case. We should be careful for the development of secondary amyloidosis even in young RA patients with short history of RA, when the disease is active.

Platelet-activating factor plays an important role in reperfusion injury in myocardium. Efficacy of platelet-activating factor receptor antagonist (CV-3988) as compared with leukocyte-depleted reperfusion

Although platelet-activating factor has been implicated in the pathogenesis of neutrophil-induced reperfusion injury, it has other mechanisms of direct deleterious hemodynamic effect. In this study we evaluated the definitive role of platelet-activating factor in myocardial reperfusion injury. Porcine hearts that underwent 60 minutes of normothermic ischemia with cardioplegia and 60 minutes of reperfusion under cardiopulmonary bypass were divided into three groups according to the methods of 15 minutes of controlled reperfusion: whole blood reperfusion group (n = 6), leukocyte-depleted reperfusion group (n = 6), and platelet-activating factor receptor antagonist (CV-3988) group (n = 6). At 60 minutes of reperfusion, the percentage of recovery of maximum slope of the pressure-volume relationship measured with intraventricular balloon, malondialdehyde value in coronary sinus blood, tissue adenosine triphosphate, and percentage of spontaneous defibrillation were evaluated. The receptor antagonist group showed significantly better recovery of maximum slope of the pressure-volume relationship than did the whole blood reperfusion group. Moreover, the receptor antagonist group showed significantly less release of malondialdehyde in the coronary sinus, higher values of adenosine triphosphate in the myocardium, and a higher percentage of spontaneous defibrillation than did the whole blood reperfusion group. On the other hand, the leukocyte-depleted reperfusion group showed no significant differences of maximum slope of the pressure-volume relationship, malondialdehyde, adenosine triphosphate, or spontaneous defibrillation as compared with the whole blood group. These results suggest that platelet-activating factor receptor antagonist attenuated severe damage in whole blood reperfusion of the myocardium as compared with leukocyte-depleted reperfusion, which also suggests that platelet-activating factor may play a more important role in myocardial reperfusion injury than do neutrophils.

Transport mechanism of anthracycline derivatives in rat polymorphonuclear leukocytes: uptake of pirarubicin, daunorubicin and doxorubicin

We performed experiments on the cis-inhibition and trans-stimulation effect on pirarubicin uptake in order to clarify the involvement of a carrier in the pirarubicin, daunorubicin and/or doxorubicin transport systems in rat polymorphonuclear leukocytes. The uptake of daunorubicin and doxorubicin was a saturable concentration-dependent process. Since the apparent kinetic constants, Michaelis constant (Km) and inhibition constant (Ki), were almost comparable, these drugs presented mutually competitive inhibition. Furthermore, the pirarubicin uptake by polymorphonuclear leukocytes was significantly elevated by increasing the preloaded amount of doxorubicin, indicating that there was a trans-stimulation effect on the pirarubicin transport in the leukocytes. These results suggest that carrier-mediated transport might be involved in the uptake of anthracycline derivatives, pirarubicin, daunorubicin and doxorubicin, by rat polymorphonuclear leukocytes.

Transport mechanism of anthracycline derivatives in rat polymorphonuclear leukocytes: uptake and efflux of pirarubicin

The characteristics of pirarubicin transport have been investigated in polymorphonuclear leukocytes isolated from rats. The uptake of pirarubicin by leukocytes was time-, temperature- and concentration-dependent with the maximum velocity (Vmax) of 4.84 nmol/5 x 10(6) cells/min and the Michaelis constant (Km) of 13.4 microM. The uptake depended on the extracellular pH, indicating that the molecular form of pirarubicin is more permeable than its ionic form and/or that the transporter of pirarubicin has optimal pH range. When the intracellular space was changed by increasing the medium osmolarity with sucrose, the uptake was altered by osmolarity changes and it appeared that about 27% of the drug was bound to the membrane surface. The initial uptake was inhibited by the metabolic inhibitors rotenone, 2,4-dinitrophenol and sodium cyanide. Pirarubicin accumulation in the intracellular glucose-depleted cells diminished significantly compared with that in normal cells. The efflux of pirarubicin from leukocytes was also temperature-dependent and inhibited by a metabolic inhibitor. These results indicate that a specific mechanism is concerned in the transport of pirarubicin in polymorphonuclear leukocytes.

Imaging study on the mode of development and changes in avascular necrosis of the femoral head in systemic lupus erythematosus: long-term observations

To find out when and how avascular necrosis of the femoral head (ANFH) develops in patients with SLE who are receiving corticosteroids, we carried out a 3-yr prospective study using imaging methods. Twenty-three patients with SLE who were free of hip pain and radiographically negative were enrolled in the study. Initially, abnormal findings characteristic of ANFH were detected in eight (35%) and six (26%) patients on MRI and radionuclide uptake bone scanning, respectively. During a 3-yr observation period abnormalities on MRI, bone scanning and radiography were found in four, five and four patients, respectively and three patients developed hip pain. Analyses of imaging changes demonstrated that only a small proportion of patients (2/8, 25%) who initially showed abnormal MRI progressed to be radiographically positive for ANFH over the 3 years. High doses of corticosteroids over the 3-yr period were to be responsible for the emergence of change in MRI abnormalities. It is also suggested that abnormal MRI findings tend to develop either within a relatively short interval after the start of corticosteroid treatment or are associated with the exacerbation of SLE.

Felodipine therapy may not alter glucose and lipid metabolism in hypertensives. Felodipine Multicenter Prospective Study Group in Japan

The effects of long-term monotherapy with felodipine, a calcium antagonist, on blood pressure, glucose tolerance, and serum lipid profiles were prospectively investigated in 51 hypertensive patients: 13 with normal glucose tolerance and 38 with glucose intolerance. The levels of plasma glucose, serum lipids, and glycosylated hemoglobin A1c were determined before and during long-term (7.5 +/- 0.5 months; range, 6 to 9 months) therapy with felodipine. A 75-g oral glucose tolerance test was performed before and during long-term felodipine therapy. Significant decreases in both systolic and diastolic blood pressures in both patient groups were maintained during the therapy. Neither fasting nor post-glucose load venous plasma glucose levels were altered in either group of patients, and no patients with normal glucose tolerance developed diabetes mellitus during the study. Serum lipid levels did not change significantly in either group of patients except for significant decreases in high-density lipoprotein cholesterol and apolipoprotein A-I in the group with normal glucose tolerance tests, but those changes remained within the normal range. Furthermore, neither serum lipid nor apolipoprotein levels were altered, even in patients with hypercholesterolemia (total cholesterol levels, > 5.69 mmol/L = 220 mg/dL). These results suggest that long-term therapy with felodipine may not alter glucose and lipid metabolism in hypertensive patients, and felodipine appears to be useful as an antihypertensive agent for hypertensive patients with either dyslipidemia or impaired glucose metabolism.

[A case of systemic lupus erythematosus who developed nodular shadows in the lung in parallel with the disease activity]

A 35-year old woman was admitted to our hospital in April 1991 due to the appearance two nodular shadows on chest X-ray. The patient's past medical history was as follows; In 1986, she developed polyarthralgia, facial eruptions and Raynaud's phenomenon which was treated with prednisolone. In 1988, investigations revealed proteinuria where by the diagnosis of SLE complicated with lupus nephritis was established. Subsequently, treatment with cyclophosphamide was carried out. However, in January 1991, there was further increase in urine proteins in accompaniment with systemic eruptions. In addition, laboratory findings showed an increasing titre of anti-DNA antibody and decreasing serum compliments. In April 1991, as indicated before, a chest X-ray revealed nodular shadows in the right upper and lower lung fields, therefore, a transbronchial lung biopsy was performed. The histology revealed inflammatory infiltrates in the bronchoalveolar tissue, fibrosis of the septa- and exudates in the alveolar space. These findings suggested fibrosing alveolitis. It was true considered that these lesions in the lung were associated with the exacerbation of SLE. In view of this, the dose of prednisolone was increased to 60 mg/day. Consequently, the nodular shadows regressed and the clinical course of SLE improved. It is well appreciated that some patients with SLE develop variable pulmonary involvement, however, this case is of great interest due to the fact that multiple nodular shadows on chest X-ray are very rare in SLE.

Relation of blood pressure circadian rhythm to cardiovascular complaints and orthostatic test results in patients with orthostatic dysregulation. Effects of midodrine on blood pressure circadian rhythm

Twenty patients with orthostatic dysregulation were studied in order to clarify the relation of blood pressure (BP) circadian rhythm to cardiovascular complaints and orthostatic test results. There was a significant negative correlation between the number of cardiovascular complaints and 24 hour (hr) maximum (Mx) and day-time Mx BPd. A significant negative correlation was also obtained between the decrease in TII amplitude in upright posture and nighttime standard deviation and range of BPs and BPd. Decrease of BPs in upright posture was significantly correlated with 24 hr and nighttime minimum (Mn) BPd. The above results indicate that cardiovascular complaints and orthostatic test results are related with BPd, as well as BPs.

Bone marrow microenvironment of patients with systemic lupus erythematosus

In an attempt to clarify the hematologic abnormality in systemic lupus erythematosus (SLE), we studied the bone marrow microenvironment of 8 women with this disease. The number of fibroblast colonies was similar to that of healthy control individuals. Culture supernatants of monocytes obtained from the patients with SLE showed a diminished production of the hemopoietic growth factor required to stimulate bone marrow fibroblasts. As the activity of the humoral factor released from SLE monocytes was diminished, such a reduction may play a role in the pathogenesis of the hematologic abnormality seen in SLE.

Kudoa intestinalis n. sp. (Myxosporea: Multivalvulida) from the intestinal musculature of the striped mullet, Mugil cephalus, from Japan

Kudoa intestinalis n. sp. (Myxosporea: Multivalvulida) is described from the intestinal musculature of the striped mullet, Mugil cephalus, from the southeastern coast of the Kii Peninsula, Japan. The plasmodia of the new species are spherical or ellipsoidal and contain quadrangular spores that, on the average, measure 3.4 microns in length, 6.5 microns in width and 6.1 microns in thickness. The species is characterized by the presence of short projections at the apex and concave values posteriorly.

Effect of T cells on the complement production by monocytes

We studied the role of T cells in the regulation of C3 or C4 production by monocytes. While cocultured T cells reduced C3 production, they enhanced C4 production by monocytes in a number-dependent manner. Interleukin-2 enhanced these effects of T cells on C3 and C4 production, indicating that activated T cells had greater effects on complement production by monocytes. CD4+ T cells had greater effects than those of CD8+ T cells on the C3 or C4 production by monocytes, indicating that CD4+ T cells were mainly involved in the regulation of C3 and C4 production by monocytes. T-cell-conditioned medium (T-CM) also decreased C3 and enhanced C4 production, but the effect of T-CM on C3 and C4 production was less remarkable than that of T cells. T cells separated by transwell inserts from monocytes had similar effects as those of T-CM on complement production. Anti-IFN-gamma antibody completely blocked the suppressing effect on C3 production and partially blocked the stimulating effect of T cells on C4 production. These results indicate that T cells regulate C3 or C4 production by monocytes via IFN-gamma as a humoral factor. Moreover, the stimulating effect of T cells on C4 production was partially blocked when monocytes and T cells were incubated with anti-CD2, anti-LFA-1, and anti-HLA-DR antibodies, and anti-CD2 partially blocked the suppressing effect of T cells on C3 production by monocytes. These results indicate that T cells modulate the C3 and C4 production by monocytes not only via a humoral factor but also via a direct interaction with monocytes.

Host utilization by the salmon louse Lepeophtheirus salmonis (Copepoda: Caligidae) in the Sea of Japan

Two species of salmon (masu salmon Oncorhynchus masou and pink salmon O. gorbuscha) captured in the northern Sea of Japan during April 1990 were examined for infection by adult female salmon lice (Lepeophtheirus salmonis) to assess the relative importance of each to the parasite. Masu salmon had relatively low prevalence and abundance of infection and carried less than 4% of the estimated parasite population, indicating that masu salmon are utilized rarely by L. salmonis and may not be important hosts. In contrast, the infection level on pink salmon was higher, with pink salmon carrying more than 96% of the parasites found on the 2 salmon populations.

Chemical change involved in the oxidative-reductive depolymerization of heparin

A solution of hog intestinal heparin (average M(r) 12,000, anti-clotting activity 168 USP units/mg) in 0.2 M phosphate buffer (pH 7.2), was incubated in the presence of Fe2+ for 20 h at 50 degrees under an O2 atmosphere to yield oxidative-reductively depolymerized heparin (ORD heparin, average M(r) 3,000, anti-clotting activity 34 USP units/mg). Chemical analysis of the ORD heparin showed a 22, 26, and 14% loss of hexosamine, uronic acid, and N-acetyl group, respectively, but no remarkable loss of both total and N-sulfate groups. 1H and 13C NMR spectroscopic analysis indicated no decrease in the amount of L-iduronic acid 2-sulfate, but a marked loss of nonsulfated uronic acid (73 and 39% loss of D-glucuronic acid and L-iduronic acids, respectively, the sum of which corresponds to the chemically determined loss of total uronic acid). The results indicated that the ORD reaction of heparin proceeds essentially by destruction of monosaccharide units, except L-iduronic acid 2-sulfate residues, due to oxygen-derived free radicals, followed by secondary hydrolytic cleavage of the resulting unstable residues.

Sodium channel states control binding and unbinding behaviour of antiarrhythmic drugs in cardiac myocytes from the guinea pig

OBJECTIVE

The aim was to investigate whether cardiac sodium channel states (rested, activated, inactivated) regulate the binding and unbinding behaviour of antiarrhythmic drugs on the receptor sites.

METHODS

Single ventricular myocytes of adult guinea pig heart were obtained by an enzymatic dissociation method in the Langendorff manner. The channel state dependent blocking effects on cardiac sodium current (INa) of quinidine and disopyramide were studied under the whole cell variation of the patch clamp technique.

RESULTS

10 microM quinidine and 20 microM disopyramide produced similar levels of tonic block and use dependent block. The steady state inactivation curve (h infinity curve) was shifted parallel in the negative potential direction by quinidine (10 microM) and disopyramide (20 microM) to the same extent (-10 mV). Removal of the fast inactivation process of INa by chloramine-T did not reduce tonic and use dependent block by these drugs. Onset block study using a double pulse protocol revealed that block developments by both drugs were fitted to the sum of double exponential functions. However, time constant of fast phase of block by disopyramide was faster than that by quinidine, while slow phase was not significantly different. Definition of time courses of unbinding (recovery) at -140 mV indicated that quinidine dissociated relatively slowly as compared to disopyramide.

CONCLUSIONS

Quinidine produces more potent tonic and use dependent block of INa by binding to sodium channels at both rested and inactivated states, while disopyramide has a higher affinity for activated state. Therefore, sodium channel states regulate the binding and unbinding behaviour of antiarrhythmic drugs. Furthermore, the fast inactivation process is not essential in producing tonic and use dependent block by antiarrhythmic drugs.

Effects of cell differentiation on the synthesis of the third and fourth component of complement (C3, C4) by the human monocytic cell line U937

Association of complement synthesis with cell differentiation in U937 cells was investigated using granulocyte-macrophage colony-stimulating factor (GM-CSF), vitamin D3 and interferon-gamma (IFN-gamma) as differentiation-inducing agents. GM-CSF or vitamin D3 enhanced the synthesis of the third component of complement (C3) by U937 cells, but had no stimulatory effect on the synthesis of the fourth component of complement (C4). IFN-gamma increased both C3 and C4 synthesis by U937 cells. Combination of two of these three agents resulted in synergistic enhancement and all three agents caused maximal enhancement of C3 synthesis. Vitamin D3 enhanced IFN-gamma-induced C4 synthesis by U937 cells. These results were confirmed by ELISA and SDS-PAGE after biosynthetic labelling. GM-CSF, vitamin D3 or IFN-gamma increased the expression of complement receptor type 3 (CR3), one of the markers of monocyte/macrophage differentiation. Two of these agents caused a further increase and all three agents maximal increase in CR3 expression. Since C3 was synthesized in parallel with the degree of CR3 expression, the synthesis of C3, but not C4, by U937 cells is thought to be closely related to cell differentiation. It was reconfirmed that the synthesis of C3 and C4 by U937 cells was independently regulated.

Distribution of pirarubicin in human blood

We investigated the distribution and stability of pirarubicin in human blood obtained from 12 healthy volunteers. The distribution of pirarubicin into blood cells showed marked temperature- and concentration-dependencies and the Arrhenius plot for pirarubicin uptake in blood was biphasic. Therefore, pirarubicin appears to be taken up into blood cells by a carrier-mediated system. Pirarubicin was mainly enzymatically metabolized to pirarubicinol in blood cells, but pirarubicin was not metabolized into doxorubicin in either blood or plasma. On the other hand, in plasma, pirarubicin was degraded to unknown inactive compounds instead of pirarubicinol. It is therefore suggested that blood cells serve to protect against the degradation of pirarubicin into inactive compounds in blood. Accordingly, when the monitoring of pirarubicin and its active metabolites is carried out in patients, both blood and plasma must be frozen immediately after blood collection.

Okadaic acid enhances human T cell activation and phosphorylation of an internal substrate induced by phorbol myristate acetate

Okadaic acid is a potent tumor promoter and an inhibitor of serine/threonine-specific protein phosphatases. We studied the effect of okadaic acid in human T cell activation and phosphorylation of internal substrates. Okadaic acid at up to 4 nM enhanced phorbol myristate acetate (PMA)-induced proliferation and CD25 (IL-2 receptor, p55) expression, although it showed no activation by itself. Okadaic acid induced hyperphosphorylation of a 60 kDa protein in T cells as well as non-T cells, as reported in fibroblasts and keratinocytes. Preincubation with 4 nM okadaic acid enhanced PMA induced phosphorylation of the 80 kDa protein, an internal substrate of protein kinase C in T cells. These results suggest that okadaic acid inhibited dephosphorylation of protein kinase C specific substrates, and as a result, enhanced T cell activation mediated by protein kinase C pathway.

Effects of Pectenophilus ornatus (Copepoda) on the biomass of cultured Japanese scallop Patinopecten yessoensis

There was a negative relationship between the number of parasitic copepods (Pectenophilus ornatus) and the dry weight condition index of the infected Japanese scallop (Patinopecten yessoensis) cultured in the Tsugaru Strait of northern Japan. The parasite is considered a serious pest of the commercial bivalve in cases of heavy infection.

Synthesis and regulation of the fourth component of complement (C4) in the human monocytic cell line U937: comparison with that of the third component of complement (C3)

Production of the fourth component of complement (C4) by the human monocytic cell line U937 and its regulation were investigated in comparison with the production of the third component of complement (C3) in a cell culture system. Although no detectable C4 was produced by U937 without stimulation, U937 was induced by recombinant interferon-gamma (IFN-gamma) to synthesize C4 in a dose- and time-dependent fashion. The production of C4 was reversibly inhibited by cycloheximide, indicating that it resulted from de novo synthesis. The C4 synthesized by U937 cells was functionally active as assessed by haemolytic assay. SDS-PAGE following biosynthetic labelling showed that subunit structure of C4 synthesized by U937 cells was identical with that of plasma C4 but that molecular weight of alpha-chain was greater than that of plasma C4. We compared the regulation of C4 synthesis with that of C3 synthesis. Although C3 synthesis by U937 cells was enhanced by IFN-gamma, lipopolysaccharide (LPS) and phorbol myristate acetate (PMA), C4 synthesis was induced only by IFN-gamma. LPS and IFN-gamma induced a synergistic increase in C3 synthesis by U937 cells. U937 cells incubated with LPS and IFN-gamma synthesized a greater amount of C4 than those incubated with IFN-gamma alone. Thus it was demonstrated that the synthesis of C3 and C4 was independently regulated. This study shows that the U937 cell line provides a useful model for studies on the synthesis of complement proteins and on the regulation of complement production.

[A case of primary biliary cirrhosis with negative anti-mitochondrial antibody anteceded by rheumatoid arthritis]

We report a case of primary biliary cirrhosis with negative anti-mitochondrial antibody which were anteceded by rheumatoid arthritis. The patient was a 46-year-old female who was admitted due to low grade fever and elevated serum alkaline phosphatase (ALP) and gamma-glutamyl transpeptidase (gamma-GTP) levels. She had been diagnosed as having erythema nodosum and rheumatoid arthritis 6 years before. Her family history disclosed that her mother had rheumatoid arthritis and her sister systemic lupus erythematosus. On admission, she had moderately elevated erythrocyte sedimentation rate, and elevated serum ALP, gamma-GTP and IgM levels. Anti-mitochondrial antibody and anti-pyruvate dehydrogenase complex antibody were negative but anti-nuclear antibody was positive. However, the histology of liver showed chronic non-suppurative destructive cholangitis. AMA was always negative and serum ALP and bilirubin levels remained constant during the following two years. The pathogenesis of primary biliary cirrhosis with negative anti-mitochondrial antibody is discussed.

Case report: nifedipine-rifampicin interaction attenuates the effect on blood pressure in a patient with essential hypertension

A 72-year-old woman with 5-year history of essential hypertension developed peritoneal tuberculosis. The patient's hypertension, which had been well-controlled by long-acting nifedipine, deteriorated after the administration of rifampicin, an antitubercular agent. During use of nifedipine and rifampicin, both the peak plasma concentration and the area under the curve of nifedipine decreased markedly to about 40% of those without rifampicin. The findings suggest that rifampicin may increase the elimination of nifedipine, presumably by induction of its hepatic metabolism. Nisoldipine, another calcium antagonist, also failed to lower the patient's blood pressure, when given in combination with rifampicin. Taken together, these findings indicate that more caution should be urged when calcium antagonist is prescribed along with rifampicin.

Determination of tolperisone enantiomers in plasma and their disposition in rats

A stereoselective assay for the determination of tolperisone enantiomers in plasma by high performance liquid chromatography was developed. Calibration curves obtained for the enantiomers were linear over plasma concentrations of 0.1-3.0 micrograms/ml with a detection limit of 20 ng/ml. Following intravenous bolus administration of 10 mg/kg of racemic tolperisone to rats, stereoselective disposition of tolperisone enantiomers was observed, and plasma concentrations were significantly higher for l-tolperisone than for d-tolperisone at 5, 15 and 30 min after administration. When either enantiomer was administered alone to rats, both enantiomers were found in plasma, indicating that a mutual chiral inversion occurs in the body.

[Herpes zoster in connective tissue diseases: II. Rheumatoid arthritis and mixed connective tissue disease in comparison with systemic lupus erythematosus]

We investigated the incidence of herpes zoster (HZ) and the immunological state to HZ in patients with rheumatoid arthritis (RA) and mixed connective tissue disease (MCTD) in comparison with systemic lupus erythematosus (SLE). HZ occurred in 6 (25%) out of 24 patients with RA and 4 (22%) out of 18 patients with MCTD. One patient had had HZ before the diagnosis of RA. On the other hand, all 4 patients with MCTD had had HZ before the diagnosis of MCTD. The patients with RA and MCTD showed normal or higher antibody titers to varicella zoster virus (VZV) than normal subjects as assayed by both complement fixation technique and neutralization test. However, the antibody levels were not very high compared to those in patients with SLE. On the other hand, only 7 (50%) of 14 patients with RA and 4 (40%) of 10 patients with MCTD showed positive skin reactions to VZV antigen, whereas all 15 normal subjects had positive reactions. Thus, cellular immunity to VZV was thought to be impaired in these diseases. In the patients who were receiving less than 10 mg/day of prednisolone, 7 (64%) of 11 had positive skin reactions in RA patients and 3 (60%) out of 5 patients with MCTD, whereas none (0%) out of 3 patients with RA and 1 (20%) out of 5 patients with MCTD who were receiving 10 mg/day or more prednisolone showed positive skin reactions. These results suggest that the high incidence of HZ in patients with RA and MCTD is probably due to an impaired cellular immunity as in the case of SLE.

Successful treatment of acute right cardiac failure due to pulmonary thromboembolism in mixed connective tissue disease

Mixed connective tissue disease (MCTD) is characterized as a benign rheumatic disease with a favorable response to therapy. When pulmonary hypertension is a complication, however, it is often reported to be fatal. A 32-year-old female patient with MCTD who had developed rapidly progressive pulmonary hypertension and disseminated intravascular coagulopathy was admitted to our hospital and was successfully treated with corticosteroids and anticoagulants. The failure of microcirculation due to coagulopathy is considered to be one of the possible entities of pulmonary hypertension.

A defect in the protein kinase C system in T cells from patients with systemic lupus erythematosus

To determine whether there is an intrinsic defect in T cells from patients with systemic lupus erythematosus (SLE), we studied signal transduction systems, assaying the total protein kinase C (PKC) levels and the phorbol myristate acetate (PMA)-induced activation of PKC in PHA-treated T cells. T cells from SLE patients showed a decrease in proliferation in response to PMA, but not to PHA, thereby suggesting the existence of an intrinsic abnormality in the PKC-mediated activation pathway. Total PKC activity in the T cells from SLE patients was significantly decreased. Although stimulation with PMA induced a translocation of PKC from the cytosol to the particulate fraction, translocated PKC activity after 2 nM PMA treatment was decreased in the SLE T cells. Furthermore, PMA-induced phosphorylation of 80-kDa substrates was also decreased in SLE T cells. These results suggest that there is a reduced PKC activity and an impaired PKC activation in response to PMA in the SLE T cells, a finding which may explain, if partially, the defect in T cell activation in patients with SLE.

Haemostatic factors associated with vascular thrombosis in patients with systemic lupus erythematosus and the lupus anticoagulant

To elucidate the mechanism of vascular thrombosis in patients with systemic lupus erythematosus and the lupus anticoagulant changes in factors associated with haemostasis were investigated. The lupus anticoagulant was associated with an increased incidence of thrombosis, particularly cerebral thrombosis. Concentrations of fibrinopeptide A and fibrinopeptide B beta 15-42 were significantly raised in the plasma of patients with systemic lupus erythematosus and the anticoagulant compared with concentrations in patients without the lupus anticoagulant. The tendency towards formation of thrombosis was not found in all lupus patients with the anticoagulant, however. Concentrations of thromboxane B2 were remarkably raised in the plasma of the two patients with the lupus anticoagulant who had recently had thrombosis. Concentrations of 6-keto-prostaglandin F1 alpha, protein C, antithrombin III, and plasminogen were similar in both groups. No significant decrease in serum stimulatory activity on prostacyclin production by cultured aortic endothelial cells was noted in lupus patients with the anticoagulant, but inhibition was present in the two patients with recent thrombosis. These results indicate that although patients with the lupus anticoagulant are not always in a hypercoagulable state, haemostatic abnormalities found in some patients with the anticoagulant may be predictive of thrombotic events.

Left ventricular function in patients with stable systemic lupus erythematosus

Echocardiography was used to compare the left ventricular function of 43 female patients with stable systemic lupus erythematosus with 93 healthy females in 3 age groups. Left ventricular systolic function was evaluated by the left ventricular ejection fraction and left ventricular diastolic function was evaluated by the diastolic descent rate of the anterior mitral leaflet (DDR), the ratio of mean systolic velocity to mean diastolic velocity in the left ventricular posterior wall (D/S ratio) and the ratio of peak mitral inflow velocity during the atrial filling period to that in the early filling period (A/E ratio). The left ventricular ejection fraction was not significantly different between patients and normal subjects. However, left ventricular diastolic function evaluated by these indexes in patients was different from normal subjects. These data suggest that left ventricular diastolic function is lower in patients with stable systemic lupus erythematosus than in normal subjects. It appears to deteriorate progressively with age. However, left ventricular systolic function remains normal.

[Herpes zoster in connective tissue diseases: I. Association with systemic lupus erythematosus and its immunological abnormalities]

We determined the incidence of herpes zoster (HZ) in 119 patients with systemic lupus erythematosus (SLE). HZ occurred in 56 patients (47%), and 9 patients had had HZ even before SLE developed. After diagnosis of SLE, an incidence of zoster was high, 5.45 cases per 100 person-years. It was found that the susceptibility to HZ was not related to the presence of renal disorder or maximum dose of corticosteroids. The patients with SLE who had had HZ showed significantly higher antibody titers than those without a history of HZ and normal subjects as assayed by both complement fixation technique and neutralization test. On the other had, only 17 of 55 patients (31%) with SLE showed positive skin reactions to varicella zoster virus (VZV) antigen, whereas all 15 normal subjects had positive reactions. In the patients who were receiving less than 10 mg/day of prednisolone, 11 of 17 (65%) had positive skin reactions to VZV antigen, whereas only 4 of 31 (13%) patients who were receiving 10 mg/day or more prednisolone showed positive reactions. It was of interest that in 7 patients with SLE who had not received corticosteroids, only 2 (29%) patients showed positive skin reactions to VZV antigen. These results suggest that high incidence of HZ in patients with SLE is probably due to an impaired cellular immunity because of both underlying disease and corticosteroid treatment.

Changes in the structure and biological property of N----O sulfate-transferred, N-resulfated heparin

The N----O sulfate transfer of heparin has been investigated as an approach to chemical 3-O-sulfation of the D-glucosamine residues in heparin. The pyridinium salt of porcine heparin was heated at 90 degrees C in solid state for 90 min (in vacuo over P2O5) to effect the transfer of the N-sulfate groups to the HO groups in the polysaccharide, followed by N-resulfation. The product (N----O sulfate-transferred, N-resulfated heparin (ST heparin] was depolymerized with HONO to generate a mixture of di- and higher oligosaccharides. The borohydride-reduced oligosaccharides were separated on Bio-Gel P-4 and DEAE-Sephacel. The disaccharide trisulfate fraction (10.4% yield) was found to be a mixture of nearly equal amounts of IdoA(2-SO4)-AManR(3,6-diSO4) and IdoA(2,3-diSO4)-AManR(6-SO4), where IdoA represents L-iduronic acid and AManR represents the alditol formed by reduction of 2,5-anhydro-D-mannose with NaBH4. Chemical and NMR spectroscopic analyses revealed that the N----O sulfate transfer proceeded preferentially at HO-3 positions in both 6-O-sulfo-D-glucosamine and 2-O-sulfo-L-iduronic acid residues. Chromatography on antithrombin III-Sepharose gel indicated that the structural change involved in ST heparin resulted in an obvious increase in the ability to bind antithrombin III. Biological examination also indicated that this structural change resulted in moderate increases in all the activities (blood anti-clotting, anti-Factor IIa, and anti-Factor Xa) and in the strength of intrinsic fluorescence of antithrombin III.

Pharmacokinetics of pirarubicin in pediatric patients

The pharmacokinetics of pirarubicin and its active metabolite, doxorubicin, were studied after intravenous administration of pirarubicin (25-45 mg/m2) to ten pediatric patients. The concentration-time curves of pirarubicin in both blood and plasma showed representative biphasic patterns. Pirarubicin concentrations decreased rapidly from 0.5 to 2 h after administration and then decreased slowly until 24 h in all subjects. High concentrations of the metabolite, doxorubicin, were detected at 0.5 h after administration of pirarubicin which decreased gradually until 24 h. The area under the concentration-time curve from 0 to 24 h (AUC0-24) of pirarubicin and doxorubicin in blood were 3-4 times higher than those in plasma, suggesting that these drugs had a high affinity for blood cells. The AUC0-24 ratio of doxorubicin to pirarubicin in plasma was calculated to be 0.441. It might be indicated that not only pirarubicin but also doxorubicin are responsible for the therapeutic efficacy and the incidence of toxicity of pirarubicin. The pharmacokinetics of pirarubicin in pediatric patients was fundamentally similar to that of adults, but it was recognized that considerable interindividual variation in the disposition of pirarubicin and doxorubicin exists.