Comparative effects of type 1 angiotensin II-receptor blockade with angiotensin-converting-enzyme inhibitor on left ventricular distensibility and collagen metabolism in spontaneously hypertensive rats

We compared the cardiac effects of the selective angiotensin II type 1 (AT1)-receptor blockade, FK-739, with an angiotensin-converting-enzyme (ACE) inhibitor, enalapril, on left ventricular (LV) distensibility and collagen metabolism in spontaneously hypertensive rats (SHRs). We treated 14-week-old SHRs with FK-739 (30 mg/kg/day) or enalapril (10 mg/kg/day) for 6 weeks. Both FK-739 and enalapril induced a significant decrease in blood pressure (p < 0.001) and regression of LV hypertrophy (p < 0.001) compared with vehicle, with no differences between the treated groups. Furthermore, FK-739 caused a greater decrease in LV collagen content than did enalapril (FK-739-treated group, 3.06 +/- 0.11 mg/g; enalapril-treated group, 3.47 +/- 0.05 mg/g; p = 0.015) with no change in collagen phenotypes. Hearts taken from rats treated with FK-739 also showed greater LV distensibility than those taken from enalapril-treated rats (FK-739-treated group vs. enalapril-treated group at > or = 15 mm Hg, p < 0.001). These results suggest that, compared with ACE inhibition, AT1-receptor blockade may have additional effects on LV distensibility and collagen metabolism in the regression of LV hypertrophy induced by pressure overload.

The effect of nifedipine on ventriculoarterial coupling in old myocardial infarction

The effect of nifedipine on ventriculoarterial coupling was examined in 8 patients with old myocardial infarction who showed a depressed ejection fraction (37 +/- 7%). Left ventricular (LV) pressure and LV volume were determined simultaneously by micromanometer and conductance catheter, respectively. We measured the slope (Ees) of the end-systolic pressure-volume relation during transient inferior vena caval occlusion, the slope (Ea) of the end-systolic pressure-stroke volume relation, the ratio of Ea to Ees (Ea/Ees), and the work efficiency (the ratio of external work to the systolic pressure-volume area) at baseline and after the sublingual administration of nifedipine (10 mg). Nifedipine slightly increased the heart rate from 71 +/- 14 to 78 +/- 17 beats/min. Although nifedipine had little effect on Ees (2.54 +/- 0.68 vs 2.47 +/- 0.62 mmHg/ml/m2, ns), it significantly decreased Ea from 3.47 +/- 1.16 to 2.37 +/- 0.54 mmHg/ml/m2. Consequently, Ea/Ees decreased from 1.42 +/- 0.47 to 0.97 +/- 0.31 and work efficiency increased from 48 +/- 12 to 59 +/- 13% after nifedipine administration. These data suggest that nifedipine reduces afterload (Ea) and improves left ventriculoarterial coupling without depressing left ventricular contractility in patients with failing hearts due to old myocardial infarction.

The effect of left ventricular chamber compliance on early diastolic filling during coronary reperfusion

This study was designed to assess the changes in left ventricular (LV) diastolic filling and to evaluate the dynamic determinants of LV diastolic filling during coronary reperfusion after acute myocardial ischemia. We examined LV diastolic pressure-volume relations (D-PVRs) using the conductance catheter technique with a high-fidelity micromanometer, and the transmitral flow using transesophageal pulsed Doppler echocardiography in 9 open-chest anesthetized dogs with the pericardium opened. We measured early diastolic peak flow velocity (E), late diastolic peak flow velocity (A), the ratio of peak E to peak A (E/A), operational chamber compliance at the minimum LV pressure [(dV/VdP) nadir], and the time constant of LV relaxation (TC). Acute regional myocardial ischemia was produced by occluding the proximal portion of the left anterior descending coronary artery. Data were acquired at baseline, 10 min after acute myocardial ischemia, and after 15 and 90 min of reperfusion under left atrial pacing at 100 beats/min. During myocardial ischemia, D-PVRs shifted upward and rightward on the same curvilinear relationship compared with that at baseline (LV end-diastolic pressure (LVEDP) from 7.3 to 10.5 mmHg, LVEDV from 25 to 31 ml, both p < 0.01), accompanied by a decrease in peak E and E/A (E from 41 to 25 cm/sec, E/A from 1.7 to 1.1, both p < 0.01) and a prolongation of TC (from 25.4 to 30.3 msec, p < 0.01). After coronary reperfusion, D-PVRs returned to baseline accompanied by an improvement in the peak E and E/A ratio. No significant changes in peak A were observed in any of the stages. There was no correlation between peak E and TC, however, a significant positive correlation was observed between peak E and (dV/VdP) nadir (r = 0.76, p < 0.01). In conclusion, this study demonstrated that, using pulsed Doppler echocardiography, the improvement of diastolic filling after coronary reperfusion was based mainly on changes in early diastolic filling, and that LV operational chamber compliance at early diastole, rather than a LV relaxation property, might play an important role in determining early diastolic filling during coronary reperfusion.

Predicting relapse of chronic myelogenous leukemia after allogeneic bone marrow transplantation by bcr-abl mRNA and DNA fingerprinting

Fourteen patients treated by allogeneic bone marrow transplantation for chronic myelogenous leukemia (CML) were evaluated by the polymerase chain reaction (PCR) for bcr-abl-specific transcripts. Nine patients were transplanted in the first chronic phase, three in the second chronic phase, and two in the accelerated phase. All patients achieved a complete cytogenetic and hematologic remission after bone marrow transplantation. Twelve patients are alive (median, 18 months; range, 5-54 months) and two patients died early. bcr-abl mRNA was persistently detectable for 6 to 54 months in four patients (patients 1, 3, 4, 6). From two of them, DNA fingerprint analysis showed only donor type DNA although bcr-abl mRNA was detectable. bcr-abl mRNA was never detectable posttransplant in three patients (patients 2, 5, 13). Six patients had detectable bcr-abl mRNA (patients 8-12, 14): by 6 months, all of these patients were bcr-abl mRNA negative. One patient (patient 7) had detectable full bcr-abl mRNA again at 12 months, but was then negative at 20 months. Ten patients (patients 2, 4-8, 10-13) had never detectable Philadelphia (Ph1) chromosome t(9.22) translocation, whereas four patients had detectable Ph1 (patient 1, 3, 9, 14); by 6 months, three of four cases were negative. One patient (patient 1) had detectable Ph1 at 44 months, but was negative at 50 months. Three of six patients who initially had bcr-abl mRNA detectable posttransplant (patient 7-9) became negative for bcr-abl mRNA at the time of development of chronic graft-versus-host disease (GVHD). These results suggest that the detection of subclinical Ph1 positive cells by PCR is not associated with imminent clinical or cytogenetic relapse. Moreover, graft-versus-leukemia (GVL) activity may contribute to the treatment of minimal residual disease in CML after allogeneic bone marrow transplantation.

Cloning and nucleotide sequence of the gene encoding dimethyl sulfoxide reductase from Rhodobacter sphaeroides f. sp. denitrificans

The gene encoding dimethyl sulfoxide (DMSO) reductase, which contains a molybdenum cofactor, of the phototrophic bacterium Rhodobacter sphaeroides f. sp. denitrificans was isolated using an oligonucleotide probe, which was synthesized based on a internal amino acid sequence of the purified enzyme. The DMSO reductase gene coded for 822 amino acids (2466 base pairs, M(r) = 89,206) as a precursor form having a signal peptide of 42 amino acids. The deduced amino acid sequence had high homology with those of some enzymes containing a molybdenum cofactor: trimethyl amine N-oxide reductase (48%), biotin sulfoxide reductase (44%), and DMSO reductase (29%) of Escherichia coli.

[Therapy related leukemia]

Eleven therapy related leukemias (TRL) who were hospitalized in the Department of Hematology and Chemotherapy, Kanagawa Cancer Center between October 1983 and December 1993 were identified. Six of the patients were males and five were females. Their median age was 62 years (range from 14 to 75). Three patients had previously received treatment for breast cancer and two patients for malignant lymphoma. The other patients had received treatment for lung cancer, urinary bladder cancer, gastric cancer, brain tumor, maxillary sinus cancer and macroglobulinemia, respectively. Seven patients had been treated with chemotherapy and four patients had been treated with chemotherapy and irradiation for the primary tumor. The TRL cases consisted of 8 acute non-lymphoid leukemias, two acute lymphoid leukemias and one hypoplastic leukemia, respectively. The status of primary tumors at the development of TRL was complete remission in ten patients and partial remission in one patient. Three of the 10 patients who received anti-leukemic therapy entered complete remission and the median survival time was 36 days (from 7 days to 489 days). One patient expired of pneumonia before he received anti-leukemic therapy. TRL patients showed poor response to chemotherapy and had poor prognosis. These data suggest that the use of reduced doses of carcinogenic drugs for primary tumors might be required to prevent the development of TRL.

Comparison of receptor-binding properties among influenza C virus isolates

A total of 10 influenza C virus strains isolated recently in Yamagata City, Japan and shown to belong to the same lineage was compared for the ability to agglutinate chicken and mouse erythrocytes under various conditions. C/Yamagata/10/89 was unique in lacking the ability to agglutinate chicken erythrocytes at a temperature > or = 4 degrees C. This isolate also agglutinated native mouse erythrocytes only very inefficiently, although the high agglutination titer was obtained with the glutaraldehyde-fixed cells. Furthermore, it was found that C/Yamagata/4/88, unlike the other isolates, agglutinated erythrocytes from chickens to lower titers than those from mice, even when assayed at 0 degree C. Comparison of the deduced amino acid sequence of hemagglutinin-esterase among the 6 representative strains including two older isolates, C/Yamagata/26/81 and C/Nara/2/85, suggested that the failures of C/Yamagata/10/89 to agglutinate chicken erythrocytes at > or = 4 degrees C and unfixed mouse erythrocytes to high titers may be due to amino acid changes at residues 337 (Glu-->Lys) and 340 (Thr-->Tyr), respectively, and that a change at residue 347 (Leu-->Ser) may be responsible for the decreased ability of C/Yamagata/4/88 to agglutinate chicken erythrocytes.

[Surgical repair of complete atrioventricular septal defect: annuloplasty by using a smaller VSD patch]

Recent policy for the intracardiac repair of complete atrioventricular septal defect (CAVSD) is demonstrated on the basis of the following theoretical background. In the normal heart, the originating portion of the ascending aorta and the crux intrude between the mitral and tricuspid orifices each from the anterior and from the posterior, separating both the orifices together with a short fibrous septal junction. In CAVSD, however, the common A-V orifice takes an elliptic form without any septal junction. It is considered beneficial, therefore, to surgically produce a short septal junction by using a smaller patch to close the ventricular portion of the AVSD. When the left lateral leaflet is larger, two leaflets valve plasty is suggested and when it is smaller, three leaflets valve plasty is suggested to reconstruct the left-sided A-V valve, although competence of the valve leaflets must be finally secured by doing repeated water injection tests. The size of the orifices of the reconstructed left-sided as well as right-sided A-V valve should also be confirmed not to be stenotic by using Hegar sizers. Since 1991, we have applied this surgical concept in 7 patients with CAVSD. Postoperatively, there was no left A-V valve regurgitation in one and slight regurgitation remained in 6 patients. The result is considered to be satisfactory. Although one patient died due to PH crisis, the cause of death was not related to valve regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)

Successful pregnancy after allogeneic bone marrow transplantation following conditioning with total body irradiation

A 23-year-old woman had a normal full-term delivery 78 months after BMT for ALL. Conditioning therapy was Ara C 1.4 g/m2 x 4, CY 60 mg/kg x 2 and TBI 2.5 Gy x 5 at a dose rate of 3.5 cGy/min. Despite GVHD prophylaxis with short-term MTX and CsA, she developed grade I acute GVHD, but showed no evidence of chronic GVHD. Following amenorrhea for 4 years, menstruation recommenced spontaneously. She had a normal pregnancy 6 years after BMT resulting in a healthy infant with simple hypospadias. This and previous reports indicate that normal pregnancy is possible after BMT with TBI in excess of 10 Gy.

Ex vivo expansion of umbilical cord blood hematopoietic progenitor cells by combinations of cytokines

Ex vivo expansion of hematopoietic progenitor cells in the umbilical cord blood mononuclear cells (CB-MNC) was investigated in liquid culture system with various combinations of cytokines (stem cell factor [SCF], interleukin [IL]-3, IL-6, granulocyte-colony stimulating factor [G-CSF], erythropoietin [EPO], and interferon [INF]-gamma). Non-lineage-committed hematopoietic progenitor cells and lineage committed hematopoietic progenitor cells were represented as CD34+CD38- and CD34+CD38+ subpopulations, respectively. Although absolute CD34+CD38- cell numbers decreased even in the presence of multicytokines, the combinations of SCF plus IL-6 and SCF plus IL-3 plus IL-6 plus IFN-gamma were significantly effective in maintaining CD34+CD38- cells than the other combinations (P < 0.05). After 4 weeks of culture. CD34+CD38- cells disappeared in all combinations of cytokines. Absolute CD34+CD38+ cell numbers increased in the presence of cytokines. Maximal expansion of CD34+CD38+ cells were observed in the combinations of SCF plus IL-3 plus IL-6 plus EPO (19.8 +/- 3.3-fold) and SCF plus IL-3 plus IL-6 plus G-CSF (18.3 +/- 2.6). The combination of SCF plus IL-3 plus IL-6 was also effective to expand CD34+CD38- cells (15.8 +/- 3.9). However, the expansion was transient and they decreased to zero within 3 weeks. In the combinations of SCF plus IL-6 and SCF plus IL-3 plus IL-6 plus INF-gamma, maximal expansion was inferior to the others but CD34+CD38+ cells were maintained more than 4 weeks. These results suggested that the indication of CBT can be expanded into older children by ex vivo augmentation of CB hematopoietic progenitor cells using multi-cytokines.

Intracellular multiplication of Legionella pneumophila in HL-60 cells functionally differentiated in response to 22-oxacalcitriol

The agent 1,25-dihydroxyvitamin D3 (D3) induces the differentiation of HL-60 human leukemia cells into functional monocyte-like cells that can support the intracellular multiplication of Legionella pneumophila. 22-Oxacalcitriol (OCT), a synthetic analogue of D3, exhibits greater differentiation-inducing activity than D3 in WEHI-3 mouse leukemia cells and has been suggested to be clinically more useful because of its lower hypercalcemic activity. The abilities of OCT and D3 to induce the functional differentiation of human leukemia HL-60 cells have now been investigated. OCT induced the differentiation of HL-60 cells into monocyte-like cells to a similar extent as D3. Thus, both OCT and D3 increased (1) the surface expression of CD11b, CD11c, CD14, and CD35; (2) nonspecific esterase staining; and (3) phagocytic activity toward fluorescent beads. HL-60 cells differentiated in response to OCT also supported the intracellular multiplication of L. pneumophila. Activation of both OCT- and D3-treated HL-60 cells with human recombinant interferon-gamma (IFN-gamma) for 24 h before infection markedly inhibited L. pneumophila multiplication. IFN-gamma activation enhanced superoxide anion generation by D3-treated HL-60 cells but not by OCT-treated HL-60 cells, suggesting that the inhibition of L. pneumophila multiplication in IFN-gamma-activated cells is independent of superoxide generation. Finally, D3, but not OCT, markedly stimulated the formation of osteoclast-like multinucleated cells from mouse bone marrow cells, consistent with the lower hypercalcemic activity of OCT.

Stage-assessment of the progress of continuous vertigo of peripheral origin by means of spontaneous and head-shaking nystagmus findings

The stages of continuous vertigo of peripheral origin were classified into nine categories according to the findings of spontaneous nystagmus (SPN) and head-shaking nystagmus (HSN). The patients analysed were 18 with vestibular neuronitis, 6 with sudden deafness and 6 with unilateral inner ear disorders. 1) Irritative SPN (Stage I) was rarely encountered. 2) SPN of the paralytic type (Stage II) was usually observed in the period less than one month after the onset of diseases. 3) HSN directed toward the intact side with or without a reversal phase (Stages III-2 and III-1, respectively) were the common types of central compensation. 4) The progress of recovery to complete cure (Stage V) was usually rapid once it had actually begun. 5) During the process of recovery, HSN could disappear transitorily (Stage III-3), or be directed toward the affected side without a reversal phase (Stage III-5). Spontaneous recovery nystagmus (Stage IV) could also occur. 6) About 40% of patients recovered to Stage V within about 4 months after the onset of vertigo, but about 30% of patients remained in Stage III-1 or III-2 even after 4 months.

A quantitative analysis of head-shaking nystagmus of peripheral vestibular origin

A quantitative analysis of horizontal head-shaking nystagmus (HSN) was made on 48 patients with unilateral peripheral vestibular lesions in conjunction with stimulus intensity. Each patient underwent three head-shaking tests with 10, 30 and 50 horizontal head-excursions at a frequency of approximately 2 Hz, and HSN was recorded on ENG with eyes open in total darkness. i) HSN appeared in a biphasic or monophasic pattern. ii) The maximal slow-phase eye velocity (MSV) of the 1st phase (PI) of biphasic HSN increased significantly in proportion to stimulus intensity, and was significantly greater than that of monophasic HSN. iii) The duration of HSN was greater in the 2nd phase (PII) of biphasic HSN than in PI and increased markedly in proportion to stimulus intensity. iv) As the stimulus intensity rose to a high level, the interval between PI and PII (2nd phase latency) shortened, and the PII tended to appear more quickly after head-shaking. It was especially noteworthy that in response to an increase in stimulus intensity, both the MSV in PI and the duration of PII of biphasic HSN increased, but the duration of PI was reversely suppressed by the PII.

Effects of nifedipine on mechanical properties of the normal and atherosclerotic descending aorta assessed by transesophageal echocardiography

We assessed the effects of calcium ion (Ca++) entry blockade (nifedipine) on the static elastic properties of the thoracic descending aorta in 60 subjects classified into 4 groups according to age and complications. The stiffness index (beta), which expresses the mechanical properties of the arterial wall, was calculated from the dimensional changes of the thoracic aorta by transesophageal echocardiography and blood pressure was determined by conventional cuff method. After administration of nifedipine, beta was significantly decreased in all groups. There was a significant correlation between beta at rest and the value of a decrease in beta after nifedipine in the relatively younger and the older groups with complications, but no significant correlation was observed in the older group without complications. Nifedipine directly reduces the stiffness of the descending aorta. The effect is stronger in relatively younger subjects, especially in subjects with risk factors of atherosclerosis and stiff descending aorta at rest. These results suggest that there may be a reversible sclerotic property of the descending aorta, probably caused by high smooth muscle tone before an irreversible atherosclerosis occurs in patients with risk factors promoting atherosclerosis.

[A simple method for differentiation of hydrogen sulfide-producing bacteria by the pH-dependent EDTA-sensitivity test]

The pH-dependent EDTA-sensitivity test was performed to differentiate several strains of bacteria forming black colonies by the production of hydrogen sulfide on TCBS (thiosulfate-citrate-bile salt-sucrose agar) medium (tentatively designated as hydrogen-sulfide production bacteria). Two halotorelant strains of 16 hydrogen sulfide-producing strains showed the same bacteriological properties and isoprenoid quinone type as did a reference strain of Proteus mirabilis and were classified into the EDTA-insensitive group as were P. mirabilis and P. vulgaris. On the other hand, the other 14 halophilic strains, showing similar but not identical bacteriological properties or the isoprenoid quinone type to those of Shewanella putrefaciens IFO 3908, were classified into the "EDTA-sensitive (at pH 5)" group as were some species of the genus Vibrio. By the same sensitivity test, S. putrefaciens IFO 3908 was classified into the "EDTA-sensitive (at any pH)" group. These results indicate that the pH-dependent EDTA-sensitivity test is useful for differentiation of bacterial isolates producing hydrogen sulfide and having similar bacteriological properties.

Clinical importance of extraordinary integration patterns of human T-cell lymphotropic virus type I proviral DNA in adult T-cell leukemia/lymphoma

The proviral DNA of human T-cell lymphotrophic virus type I (HTLV-I) is known to be integrated monoclonally in the malignant cells of adult T-cell leukemia/lymphoma (ATL), which is a peripheral T-cell malignancy caused by this virus. We studied the relationship between the integration patterns of HTLV-I and clinical characteristics in 89 patients with ATL. The proviral DNA of HTLV-I was examined by the standard Southern blot analysis using the endonucleases EcoRI and Pst I. One clear band of greater than 9 kb was detected in most of the patients (83 case) when cellular DNA was digested with EcoRI. On the other hand, extraordinary integration patterns of HTLV-I proviral DNA were detected in 6 patients; 3 of them showed two bands, while the other 3 showed one band smaller than 9 kb. When cellular DNA was digested with PstI, the band patterns of these patients were quite different from those of typical patients. The patients with the extraordinary integration patterns had clinical characteristics dissimilar to those of the other 83 patients with the ordinary integration pattern. The patients with two bands by EcoRI digestion always had severe hypoxemia with extremely high levels of serum lactate dehydrogenase at first presentation and showed peculiar organ infiltrations, such as retina and muscle, which were less frequent in the other ordinary 83 patients. They all died within 8 months after the onset. In contrast, the patients with one smaller band by EcoRI digestion always had small and mature T lymphocytes with bilobulated nuclei without lymphadenopathy and showed a favorable clinical course, which was uncommon in the ordinary cases. They were alive 20 to 38 months after diagnosis. Rearranged bands of the T-cell receptor gene were detected in all patients with unusual integration. These findings indicate that the integration patterns of HTLV-I proviral DNA have a clinical implication and may be one of the explanations for heterogeneity in the behavior of this disease.

A model study of time- and voltage-dependent effects of class I antiarrhythmic drugs in guinea-pig papillary muscles as related to external potassium concentration

1. A piecewise exponential three-state model previously introduced by the authors in 5.4 mmol/l was intended to apply to states with different [K+]o and with a different drug. Using the conventional microelectrode technique the effects of 20 mumol/l mexiletine (MEX), 5 mumol/l aprindine (APR), 20 mumol/l quinidine (QUI), 5 mumol/l flecainide (FLE), 5 mumol/l E-0747 (dl-6-chloro-2,2'-dimethyl-1'-[3-(4-hydroxypiperizino)propyl]spiro [chroman-4,4'-imidazolidine]-2',5'-dione hydrochloride and 100 mumol/l QX-222, a quaternary derivative of lidocaine, on action potentials (APs) in guinea-pig papillary muscles were studied. Specific objects of the study were (1) steady state Vmax values at various frequencies (all drugs), (2) the recovery process of Vmax in premature responses (MEX) and (3) Vmax changes during a train of stimulation at 1 Hz after a rest period (all other drugs) in 2.7 and 10 mmol/l [K+]o. Further, those of APR alone and APR plus 1 mmol/l nicorandil (NIC), which shortened action potential durations (APDs) specifically, were investigated on the above items (1) and (3) in 5.4 mmol/l [K+]o. 2. All the drugs reduced the Vmax of APs frequency-dependently and, except QX-222, more markedly in 10 mmol/l [K+]o than in 2.7 mmol/l [K+]o at 1 Hz. 3. The rate constants estimated from the model fitting characterized MEX and APR and the other drugs as predominantly inactivated and activated channel blockers, respectively. The calculated rate of onset of block, lambda T, does not differ much between the three [K+]o levels. lambda T shows that APR belongs to class Ia rather than class Ib.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of left ventricular regional nonuniformity on afterload-dependent relaxation in intact dogs

The time course of systolic loading conditions is considered an important factor in affecting left ventricular (LV) relaxation. However, the exact underlying mechanisms remain controversial. The goal of this study was to evaluate the role of the change in loading sequence on LV regional wall motion and LV relaxation. Early and late systolic loading were produced by constricting the ascending aorta and the descending aorta, respectively, in seven anesthetized dogs. In two pairs of cardiac beats with a comparable peak LV pressure during the mild and moderate constrictions of the ascending or descending aorta, we measured LV time constant (T) of LV pressure decay and determined regional nonuniformity in basal and apical segmental motion during the isovolumic relaxation period (by Lew's method). Constriction of the descending aorta led to a significant delay of the timing of peak LV pressure, associated with an increase in T, end-systolic pressure, and the regional nonuniformity between the two segments. T was correlated well with the amount of the nonuniformity, suggesting that LV regional nonuniformity between basal and apical regions might be involved in the complex mechanism of afterload-dependent relaxation.