Early vascular responses to abluminal biodegradable polymer-coated versus circumferential durable polymer-coated newer-generation drug-eluting stents in humans: a pathologic study

Background

Recent clinical trials are testing strategies for short (1–3 months) dual antiplatelet therapy (DAPT) following newer-generation drug-eluting stent (DES) placement. However, the safety of short DAPT regimens is not supported by biological evidence in humans.

Purpose

We sought to evaluate early pathologic responses to newer-generation DES by comparing abluminal biodegradable polymer-coated DES (BP-DES) with circumferential durable polymer-coated DES (DP-DES) in human autopsy cases.

Methods

The study included a total of 37 coronary lesions with thin strut newer-generation DES (DP-DES=23 [XIENCE=18, Resolute Integrity=5] and BP-DES=14 [SYNERGY=9, Ultimaster=5]) with duration of implantation <90 days in 25 autopsy cases. The process of stent healing was precisely evaluated for every single strut in association with underlying tissue characteristics. The degree of strut coverage was defined as follows: grade 0 (bare struts), grade 1 (struts covered with thrombus, fibrin, or other tissues or cells without endothelium), grade 2 (struts covered with single-layered endothelium without underlying smooth muscle cell layers), and grade 3 (struts covered with endothelium and underlying smooth muscle cell layers) (Figure 1).

Results

Duration of implantation was similar in lesions with DP-DES and those with BP-DES (median=20 vs. 17 days). A total of 1986 struts (DP-DES=1261, BP-DES=725) were pathologically analyzed. Focal grade 2 coverage was observed as early as 5 days after the implantation in both stents. Multilevel mixed-effects ordered logistic regression model demonstrated that BP-DES exhibited greater strut coverage compared with DP-DES (odds ratio; 3.50, 95% CI; 1.31–9.41, P=0.013), which remained significant after adjustment for duration of implantation and underlying tissue characteristics (odds ratio; 2.64, 95% CI; 1.04–6.68, P=0.040). The time course of vessel healing assessed as predictive probability of strut coverage (grade 0–3) stratified by duration of implantation is shown in Figure 2. Predictive probability of grade 2 and 3 coverage was comparably limited at 30 days (DP-DES=17.7% vs. BP-DES=29.0%) and increased at 90 days (DP-DES=76.1% vs. BP-DES=85.9%). Both stents showed few inflammation and similar degree of fibrin deposition.

Conclusions

The current first pathologic study on early biological responses to newer-generation DES in humans demonstrated that single-layered endothelial coverage begins in days following the stent placement, and abluminal BP-DES potentially exhibit faster strut coverage with smooth muscle cell infiltration than circumferential DP-DES. Nevertheless, vessel healing remains suboptimal at 30 days in both DP- and BP-DES, which progresses with time to become substantial at 90 days. Our results suggest that very short duration of DAPT for 1 month should be applied with caution, taking into account the trade-off between bleeding and thrombotic risks.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid for Scientific Research (C) from the Japan Society for the Promotion of Science

Abstract P368: Effects of Empagliflozin on Day-to-day Variability of Home Blood Pressure and Heart Rate in Patients with Type 2 Diabetes

Background: The effects of empagliflozin in addition to standard care, on day-to-day variability of self-measured home blood pressure (BP) and heart rate (HR) at home in patients with type 2 diabetes (T2DM) at high cardiovascular risk are not known.

Method: We followed twenty-three consecutive T2DM patients (mean age: 69 years old, 12 men) to add 10 mg of empagliflozin once daily for three months. Home BP and HR were measured once every morning at home, using an oscillometric device. The variability of BP and HR were defined as the standard deviations (SD) of measurements which were performed on seven consecutive days.

Results: For home blood pressure, empagliflozin significantly reduced systolic blood pressure (SBP) from 130±11 mmHg at baseline to 126±11 mmHg at the first week(1W) of the administration (P<0.05). SBP achieved the target home BP goal (125±11 mmHg) at the second week(2W) and was maintained during the study (P<0.01). As regards day-to-day variability of SBP, SD decreased from 7.3±3.5 mmHg at baseline to 6.7±2.5 mmHg at 1W (4W: 6.4±2.8 mmHg, 8W: 5.2±2.3 mmHg, P<0.05). In diastolic blood pressure (DBP), there was a significant reduction of SD compared with that at baseline (4.9±1.6 mmHg at baseline, 4W: 4.3±1.6 mmHg, 8W: 3.9±1.8 mmHg, 12W: 4.4±1.6 mmHg, P<0.05); however, there was no change of DPB (71±10 mmHg at baseline, 12W: 71±8 mmHg). Similarly, there was a decreasing trend in SD of HR (3.9±1.0 beats per minute (bpm) at baseline, 4W: 3.3±1.3 bpm, 12W: 3.1±1.3 bpm, P<0.1), although there was no significant change in HR (62±13 bpm at baseline, 12W: 61 ± 12 bpm).

Conclusion: Empagliflozin tended to reduce the day-to-day variability of self-measured morning home BP and HR.

Impact of Bacillus amyloliquefaciens S13-3 on control of bacterial wilt and powdery mildew in tomato

BACKGROUND

Biological control is a non-hazardous technique to control plant diseases. Researchers have explored microorganisms that show high plant-disease control efficiency for use as biological control agents.

RESULTS

A single soil application of Bacillus amyloliquefaciens strain S13-3 suppressed tomato bacterial wilt caused by Ralstonia solanacearum, a soilborne bacterial pathogen, through production of antibiotics augmented possibly by induction of systemic acquired resistance. Soil application also controlled tomato powdery mildew disease through induction of systemic acquired resistance.

CONCLUSION

S13-3 showing bifunctional activity with a single application to soil may be an innovative biological control agent against bacterial wilt and powdery mildew in tomato.

Cyclic lipopeptide iturin A structure-dependently induces defense response in Arabidopsis plants by activating SA and JA signaling pathways

Iturin A is the most well studied antifungal cyclic lipopeptide produced by Bacillus species that are frequently utilized as biological control agents. Iturin A not only shows strong antifungal activity against phytopathogens but also induces defense response in plants, thereby reducing plant disease severity. Here we report the defense signaling pathways triggered by iturin A in Arabidopsis salicylic acid (SA) or jasmonic acid (JA)-insensitive mutants. Iturin A activated the transcription of defense genes PR1 and PDF1.2 through the SA and JA signaling pathways, respectively. The role of iturin A as an elicitor was dependent on the cyclization of the seven amino acids and/or the β-hydroxy fatty acid chain. The iturin A derivative peptide, NH2-(L-Asn)-(D-Tyr)-(D-Asn)-(L-Gln)-(L-Pro)-(D-Asn)-(L-Ser)-COOH, completely suppressed PR1 and PDF1.2 gene expression in wild Arabidopsis plants. The identification of target molecules binding to iturin A and its derivative peptide is expected to shed new light on defense response in plants through the SA and JA signaling pathways.

High-resolution mapping of zym, a recessive gene for Zucchini yellow mosaic virus resistance in cucumber

Using a high-resolution mapping approach, we identified a candidate gene for ZYMV resistance in cucumber. Our findings should assist the development of high-versatility molecular markers for MAS for ZYMV resistance. Zucchini yellow mosaic virus (ZYMV) causes significant disease, which leads to fruit yield loss in cucurbit crops. Since ZYMV resistance is often inherited recessively in cucumber, marker-assisted selection (MAS) is a useful tool for the development of resistant cucumber cultivars. Using 128 families of an F2:3 population derived from a cross between susceptible 'CS-PMR1' and resistant 'A192-18' cucumber inbred lines, we confirmed that ZYMV resistance is conferred by a single recessive locus: zym (A192-18) . We constructed a cucumber genetic linkage map that included 125 simple sequence repeat (SSR) markers segregating into 7 linkage groups (chromosomes). The zym (A192-18) locus was mapped to chromosome 6, at genetic distances of 0.9 and 1.3 cM from two closely linked SSR markers. For high-resolution genetic mapping, we identified new molecular markers cosegregating with the zym (A192-18) locus; using cucumber genomic and molecular marker resources and screening an F2 population of 2,429 plants, we narrowed down the zym (A192-18) locus to a <50-kb genomic region flanked by two SSR markers, which included six candidate genes. Sequence analysis of the candidate genes' coding regions revealed that the vacuolar protein sorting-associated protein 4-like (VPS4-like) gene had two SNPs between the parental lines. Based on SNPs of the VPS-4-like gene, we developed zym (A192-18) -linked DNA markers and found that genotypes associated with these markers were correlated with the ZYMV resistance phenotype in 48 cucumber inbred lines. According to our data, the gene encoding VPS4-like protein is a candidate for the zym (A192-18) locus. These results may be valuable for MAS for ZYMV resistance in cucumber.

Ezetimibe Reduces Urinary Albumin Excretion in Hypercholesterolaemic Type 2 Diabetes Patients with Microalbuminuria

OBJECTIVE: This study investigated the effects of ezetimibe, an inhibitor of intestinal cholesterol absorption, on early phase diabetic nephropathy. METHODS: A total of 32 hypercholesterolaemic type 2 diabetes patients with microalbuminuria, defined as a urinary albumin excretion (UAE) ≥ 30 but < 300 mg/g creatinine, were enrolled. Various clinical and laboratory parameters were determined at baseline and after 6 months of treatment with 10 mg/day ezetimibe. RESULTS: Ezetimibe treatment significantly decreased glycated haemoglobin (HbA1c), low-density lipoprotein-cholesterol (LDL-C), triglycerides and UAE, and significantly increased high-density lipoprotein-cholesterol and albumin. It also decreased the serum level of monocyte chemoattractant protein-1 (MCP-1), but this difference was not statistically significant. Univariate analyses showed a correlation between UAE and body mass index, systolic and diastolic blood pressures, HbA1c, LDL-C, estimated glomerular filtration rate (inverse), creatinine and MCP-1. Since these parameters may be closely correlated with each other, multiple stepwise regression analysis was performed and demonstrated that HbA1c and MCP-1 were independent determinants of UAE. CONCLUSIONS: Ezetimibe may be a promising therapeutic strategy for improving albumin excretion, partly through its anti-inflammatory properties, and for reducing LDL-C in hypercholesterolaemic type 2 diabetes patients with microalbuminuria.

Rapid detection of Escherichia coli contamination in packaged fresh spinach using hyperspectral imaging

A rapid method based on hyperspectral imaging for detection of Escherichia coli contamination in fresh vegetable was developed. E. coli K12 was inoculated into spinach with different initial concentrations. Samples were analyzed using a colony count and a hyperspectroscopic technique. A hyperspectral camera of 400-1000 nm, with a spectral resolution of 5 nm was employed to acquire hyperspectral images of packaged spinach. Reflectance spectra were obtained from various positions on the sample surface and pretreated using Sawitzky-Golay. Chemometrics including principal component analysis (PCA) and artificial neural network (ANN) were then used to analyze the pre-processed data. The PCA was implemented to remove redundant information of the hyperspectral data. The ANN was trained using Bayesian regularization and was capable of correlating hyperspectral data with number of E. coli. Once trained, the ANN was also used to construct a prediction map of all pixel spectra of an image to display the number of E. coli in the sample. The prediction map allowed a rapid and easy interpretation of the hyperspectral data. The results suggested that incorporation of hyperspectral imaging with chemometrics provided a rapid and innovative approach for the detection of E. coli contamination in packaged fresh spinach.

Urinary liver-type fatty acid-binding protein levels for differential diagnosis of idiopathic focal glomerulosclerosis and minor glomerular abnormalities and effect of low-density lipoprotein apheresis

AIMS

Focal glomerulosclerosis (FGS) and minor glomerular abnormalities are kidney diseases characterized by massive proteinuria. Urinary liver-type fatty acid-binding protein (L-FABP), an intracellular carrier protein of free fatty acids, is expressed in proximal tubules of the human kidney. Patients with FGS show significant improvement with low-density lipoprotein (LDL) apheresis. The aim of the present study was to determine whether urinary L-FABP levels differ between patients with FGS and those with minor glomerular abnormalities and whether levels are altered by LDL apheresis.

PATIENTS AND METHODS

There were 24 patients with minor glomerular abnormalities (nephrotic stage, n = 14, remission stage, n = 10), 17 patients with FGS, and 20 healthy age-matched subjects were included in the present study. Urinary L-FABP levels were measured by enzyme-linked immunosorbent assay and compared. All patients with minor glomerular abnormalities at the nephrotic stage received prednisolone for 6 months, and all FGS patients received some form of immunosuppression therapy with prednisolone, cyclophosphamide or mizoribine for 12 months. LDL apheresis was performed in eight FGS patients with drug-resistant nephrotic syndrome.

RESULTS

Urinary L-FABP levels were significantly higher in the 17 FGS patients (82.0 +/- 44.4 microg/g.Cr) than in the 24 patients with minor glomerular abnormalities (10.2 +/- 8.4 microg/g.Cr) (p < 0.01) and in the 20 healthy subjects (7.4 +/- 4.2 microg/g.Cr) (p < 0.01). Urinary L-FABP levels differed little between nephrotic stage and remission stage in patients with minor glomerular abnormalities. Urinary L-FABP levels were significantly higher in the eight drug-resistant FGS patients (122.6 +/- 78.4 microg/g.Cr) than in the nine drug-sensitive FGS patients (45.9 +/- 32.0 microg/g.Cr). Urinary L-FABP levels did not correlate with levels of other clinical markers including serum creatinine, urinary protein, and urinary N-acetyl-beta-D- glucosaminidase. In the eight drug-resistant FGS patients, LDL-apheresis significantly reduced urinary protein excretion (p < 0.01) and urinary L-FABP levels (p < 0.01).

CONCLUSIONS

Urinary L-FABP may be a useful diagnostic indicator for differentiation between FGS and minor glomerular abnormalities. LDL apheresis may be effective in ameliorating tubulointerstitial lesions associated with FGS.

Low-density lipoprotein apheresis in a patient with arteriosclerosis obliterans and light chain deposition disease

A 49-year-old women with arteriosclerosis obliterans (ASO) complicated with light chain deposition disease (LCDD) is described. Renal biopsy showed a diffuse mesangial nodular lesion and tubulointerstitial changes. Congo red and lambda light chain staining were negative; however, the kappa light chain was positive in both glomeruli and tubular basement membranes by immunostaining. Using electron microscopy, electron-dense materials were found within glomerular basement membrane, mesangium and tubular basement membrane. The patient had renal dysfunction and nephrotic syndrome with progressive skin ulcers in the left leg. The patient was diagnosed as ASO with LCDD. She received low-density lipoprotein (LDL) apheresis once weekly for 10 consecutive weeks. Serum total cholesterol and phospholipid levels were decreased, and serum creatinine and blood urea nitrogen levels also tended to decline after treatment. Urinary protein excretion was reduced markedly, and hypoalbuminemia was also improved. Ischemic symptoms including leg pain and leg coldness and numbness improved after apheresis. The walking distance increased on a treadmill. The skin temperature was increased from 33.8 degrees C to 35.5 degrees C after apheresis and the skin ulcers were also improved. Plasma nitric oxide (NO) levels were increased from 66.0 microM/l to 88.0 microM/l and plasma endothelin (ET)-1 levels were decreased from 14.5 pg/ml to 5.8 pg/ml after apheresis. LDL apheresis was effective in ameliorating hyperlipidemia, massive proteinuria, hypoalbuminemia and high serum creatinine levels in an LCDD patient with nephrotic syndrome. Furthermore, we showed beneficial effects of LDL apheresis on skin ulcers due to ischemia in an ASO patient complicated with LCDD.

Adaptation of cardiovascular responses to repetitive umbilical cord occlusion in the late gestation ovine fetus

1. The impact of repeated umbilical cord occlusion on the normal maturation of fetal heart rate (FHR) and mean arterial pressure (MAP) and the cardiovascular responses to successive umbilical cord occlusion was investigated over a 21 day period in the latter part of gestation. 2. Fifteen chronically instrumented sheep (control group n = 6; occlusion group n = 9) were studied for 21 days (113-133 days of gestation, term = 145 days) with umbilical cord occlusions (90 s duration) performed every 30 min for 1-4 h each day. On days 1, 9 and 18, FHR, FHR variation and MAP were monitored continuously and fetal arterial blood gases, pH and metabolites were measured at predetermined intervals. The baroreflex response to 75-100 microg phenylephrine (I.V.) was tested on days 1 and 18. 3. Basal FHR decreased (DeltaFHR: control, 34.6 +/- 3.6 beats x min(-1); occlusion, 36.9 +/- 2.7 beats x min(-1)) and MAP increased (DeltaMAP: control, 3.1 +/- 1.7 mmHg; occlusion, 5.2 +/- 2.1 mmHg) to a similar extent in control and occlusion groups between days 1 and 21 of the study. There was a small decline in FHR variation over the 21 day study in occlusion, but not control, group fetuses. 4. The magnitude of the fall in FHR decreased and the rise in MAP increased, despite similar changes in blood gases in response to umbilical cord occlusion, over the course of the 21 day study. Despite a significant decline in the ratio of DeltaFHR to DeltaMAP on days 9 and 18 compared to day 1, there was no difference between control and occlusion groups in baroreflex sensitivity. However DeltaFHR/DeltaPO2, an index of chemoreceptor sensitivity, had decreased by day 9 and 18 compared to day 1. 5. The cardiovascular responses to umbilical cord occlusion are altered with repetitive occlusions during the latter part of gestation, with a decrease in DeltaFHR/DeltaMAP, which does not involve changes in baroreflex sensitivity, but may involve changes in chemoreceptor sensitivity. However, repeated umbilical cord occlusion appears to have no impact on baseline cardiovascular control since there was no change in the normal maturational decrease in FHR and rise in MAP.

Intermittent umbilical cord occlusion in the ovine fetus: effects on blood glucose, insulin, and glucagon and on pancreatic development

OBJECTIVE

To determine whether repetitive umbilical cord occlusion resulting in fetal hypoxemia but not cumulative acidosis also affects fetal glucose levels and the levels of the regulatory hormones insulin and glucagon, by altering glucose delivery and with repetitive insults by inducing fetal glucose production, thus possibly affecting pancreatic development.

METHODS

Fifteen chronically catheterized fetal sheep were studied over 21 days. Umbilical cord occlusions (UCOs) (duration 90 seconds) were performed every 30 minutes for 3-4 hours each day. Fetal arterial blood was sampled at predetermined times on days 1, 9, and 18 for blood gases, pH, glucose, lactate, insulin, and glucagon. When animals were sacrificed, fetal pancreatic tissues were collected for insulin immunostaining.

RESULTS

Blood glucose decreased acutely with each UCO but showed a cumulative increase of approximately 30% over the course of each sampling day. Although plasma insulin levels also increased over the course of sampling on days 9 and 18, plasma glucagon levels remained unchanged throughout the study. The percentage of pancreatic islet cells immunopositive for insulin, which averaged 67%, was also unchanged in experimental compared with control animals.

CONCLUSION

Umbilical cord occlusion during the latter part of pregnancy, which caused severe but limited hypoxemia, also resulted in acute decreases in blood glucose levels because of reduced exogenous glucose delivery and a cumulative increase in glucose in response to repetitive insults, possibly by inducing fetal glucose production, enhancing glucose delivery, or both. However, repetitive UCO as studied had minimal effect on plasma insulin levels and no effect on glucagon levels or on pancreatic immunostaining for insulin, and thus had no evident effect on pancreatic development.

The experimental herbicide CGA 325'615 inhibits synthesis of crystalline cellulose and causes accumulation of non-crystalline beta-1,4-glucan associated with CesA protein

Developing cotton (Gossypium hirsutum) fibers, cultured in vitro with their associated ovules, were used to compare the effects of two herbicides that inhibit cellulose synthesis: 2,6-dichlorobenzonitrile (DCB) and an experimental thiatriazine-based herbicide, CGA 325'615. CGA 325'615 in nanomolar concentrations or DCB in micromolar concentrations causes inhibition of synthesis of crystalline cellulose. Unlike DCB, CGA 325'615 also causes concomitant accumulation of non-crystalline beta-1,4-glucan that can be at least partially solubilized from fiber walls with ammonium oxalate. The unusual solubility of this accumulated glucan may be explained by its strong association with protein. Treatment of the glucan fraction with protease changes its size distribution and leads to precipitation of the glucan. Treatment of the glucan fraction with cellulase digests the glucan and also releases protein that has been characterized as GhCesA-1 and GhCesA-2--proteins that are believed to represent the catalytic subunit of cellulose synthase. The fact that cellulase treatment is required to release this protein indicates an extremely tight association of the glucan with the CesA proteins. In addition, CGA 325'615, but not DCB, also causes accumulation of CesA protein and a membrane-associated cellulase in the membrane fraction of fibers. In addition to the effects of CGA 325'615 on levels of both of these proteins, the level of both also shows coordinate regulation during fiber development, further suggesting they are both important for cellulose synthesis. The accumulation of non-crystalline glucan caused by CGA 325'615 mimics the phenotype of the cellulose-deficient rsw1 mutant of Arabidopsis that also accumulates an apparently similar glucan (T. Arioli, L. Peng, A.S. Betzner, J. Burn, W. Wittke, W. Herth, C. Camilleri, H. Hofte, J. Plazinski, R. Birch et al. [1998] Science 279: 717).

[The role of cardiac catheterization for diagnosis and treatment of pulmonary hypertension]

The role of the cardiac catheterization for diagnosis and treatment of pulmonary hypertension (PH) is very important. When mean pulmonary artery pressure increased more than 25 mmHg, then PH is defined. But this is measured accurately only by the catheterization. And we can discriminate the etiology of PH clearly by pulmonary capillary wedge pressure (Ppcw) or intra-cardiac shunt (L to R) by blood oxygen saturation step-up, and both parameters are obtained by this method. The etiology of PH is diagnosed as left sided heart failure, if Ppcw is increased more than 13 mmHg. PH is produced by congenital heart disease (ASD, VSD, PDA etc.), when the oxygen saturation step-up is recognized. And PH is induced by any pulmonary disease or pulmonary thrombo-embolism or collagen disease or liver cirrhosis or PPH, if Ppcw is normal and no oxygen step-up is recognized.

The effect of intermittent umbilical cord occlusion on insulin-like growth factors and their binding proteins in preterm and near-term ovine fetuses

Intermittent umbilical cord compression with resultant fetal hypoxia can have a negative impact on fetal growth and development. Insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) are the most important regulators of fetal growth. In preterm (107-108 days of gestation) and near-term (128-131 days of gestation) ovine fetuses, we have determined the effect of intermittent umbilical cord occlusion (UCO) over a period of 4 days on the profile and expression of IGFs and IGFBPs. In experimental group animals (preterm n=7; near term n=7) UCOs were carried out by complete inflation of an occluder cuff (duration 90 s) every 30 min for 3-5 h each day, while control fetuses (preterm n=7; near term n=7) received no UCOs. Ewes were euthanized at the end of day 4, and fetal heart, lung, kidney, liver, skeletal muscle and placenta were collected. During UCOs, PO(2! ) fell (by approximately 13 mmHg), pH fell (by approximately 0.05) and PCO(2) increased (by approximately 7 mmHg), and changed to a similar extent in both preterm and near-term groups. In both preterm and near-term groups, there was no difference in fetal body or organ weight between UCO and control fetuses. No significant changes were observed in plasma IGF-I and -II concentrations or IGFBP-1, -2, -3 or -4 levels throughout the 4-day study at either gestational age. In the preterm group UCO fetuses, IGF-II mRNA (1.2-6.0 kb) levels were lower in fetal lung (33%, P<0.05), heart (54%, P<0.01) and skeletal muscle (29%, P<0.05), but there were no differences in IGF-I mRNA levels (7.3 kb); IGFBP-2 mRNA (1.5 kb) levels were lower in the right lobe of the liver (42%, P<0.05) and kidney (22%, P<0.01), but hig! her in the heart (72%, P<0.01), while IGFBP-4 (2.4 kb) levels were lower in skeletal muscle (21%, P<0.01). In the near-term group UCO fetuses, IGFBP-2 mRNA levels were greater in the placenta (39%, P<0.05). Thus, intermittent UCO as studied has a greater effect on the expression of genes encoding certain peptides of the fetal IGF system in selected tissues in preterm fetuses than that in near-term fetuses. Altered IGFBP-2 mRNA levels with reduced IGF-II mRNA levels in selected tissues may mediate changes in growth and/or differentiation that might become apparent if the length of the UCO study were extended.

Activation of the hypothalamic-pituitary-adrenal axis with repetitive umbilical cord occlusion in the preterm ovine fetus

OBJECTIVE

To determine whether repeated hypoxic insults with umbilical cord occlusion over 4 days will lead to activation of the hypothalamic-pituitary-adrenal (HPA) axis altered adrenocortical responsiveness in the preterm ovine fetus.

METHODS

Umbilical cord occlusions of 90 seconds duration were performed every 30 minutes for 3 to 5 hours each day (experimental group n = 7, control group n = 7; at 112-116 days' gestation, term = 147 days). Arterial blood was sampled at predetermined times for blood gases and pH, plasma ACTH, and cortisol. Pituitary proopiomelanocortin (POMC) and glucocorticoid receptor (GR) mRNA also were localized and quantified by in situ hybridization.

RESULTS

During umbilical cord occlusions fetal arterial oxygen pressure (approximately 17 mmHg) and pH (approximately 0.05) decreased, and carbon dioxide pressure increased (approximately 8 mmHg) as measured on days 1 and 4, but with no cumulative blood gas or pH change over successive occlusions for any of the 4 study days. Plasma ACTH increased, as measured after cord occlusion and over the course of successive cord occlusions on days 1 and 4, and returned to control values by the next day. The cumulative increase in ACTH was much less on day 4 than day 1 (15 +/- 3 compared with 101 +/- 25 pg/mL, P <.05). Plasma cortisol increased, as measured after cord occlusion and over the course of successive cord occlusions on day 4 only (2.7 +/- 0.4 to 4. 7 +/- 0.3 ng/mL, P <.05). POMC mRNA increased 2.5-fold in the pars distalis of the pituitaries from cord occlusion compared to control fetuses, but was unchanged in the pars intermedia. GR mRNA, which was detected in the pars distalis only, was unaltered.

CONCLUSION

Repetitive umbilical cord occlusion in the preterm ovine fetus resulted in the activation of the HPA axis, with increased adrenocortical responsiveness over time, and involved differential regulation of POMC mRNA expression in the pars distalis and pars intermedia of the pituitary, but with no change in GR.

Low-dose cytarabine and aclarubicin in combination with granulocyte colony-stimulating factor (CAG regimen) for previously treated patients with relapsed or primary resistant acute myelogenous leukemia (AML) and previously untreated elderly patients with AML, secondary AML, and refractory anemia with excess blasts in transformation

We used the CAG regimen (low-dose cytarabine [10 mg/m2 per 12 hours, days 1-14], aclarubicin [14 mg/m2 per day, days 1-4], and granulocyte colony-stimulating factor [200 micrograms/m2 per day, days 1-14]) for the treatment of patients with primary resistant acute myelogenous leukemia (AML) and previously untreated elderly patients with AML, secondary AML, and refractory anemia with excess blasts in transformation (RAEB-T) in addition to relapsed AML. Forty-three of 69 (62%) patients achieved complete remission (CR), including 29 of 35 (83%) patients with relapsed AML, 1 of 8 patients with primary resistant AML, 5 of 8 elderly patients with previously untreated AML, and 8 of 18 patients with previously untreated secondary AML or RAEB-T. Ten of 22 (45%) patients > or = 65 years old achieved CR. The patients who achieved CR received at least 1 course of modified CAG therapy as the first consolidation therapy, followed by various second consolidation and intensification therapies. The median disease-free survival and overall survival were 8 and 15 months, respectively, for relapsed AML; 11 and 8 months for the elderly patients; and 8 and 17 months for secondary AML and RAEB-T. Myelosuppression was mild to moderate, and other than fever, severe nonhematologic toxicity was rare. CAG as the induction therapy seems promising for the treatment of various categories of poor-prognosis AML.

Intermittent umbilical cord occlusion in the ovine fetus near term: effects on behavioral state activity

OBJECTIVE

The purpose of this study was to determine the effects on fetal behavioral state activity of intermittent umbilical cord occlusion resulting in repetitive severe short-term hypoxemia.

STUDY DESIGN

Fifteen near-term fetal sheep (experimental group, n = 8; control group, n = 7) were studied during 4 days while behavioral and cardiovascular parameters were monitored. Each day after a 2-hour control period, cord occlusions were performed in the experimental group animals by complete inflation of an occluder cuff (duration, 90 seconds) every 30 minutes for 3 to 5 hours. Results are presented as group mean +/- SEM.

RESULTS

During umbilical cord occlusions fetal arterial PO(2) (change of 12 mm Hg), oxygen saturation (change of 40%), and glucose concentration (change of 0.3 mmol/L) fell and PCO(2) (change of 7 mm Hg) rose, but all returned toward control values after release of occlusion. Fetal behavioral state activity was markedly disrupted by 90 seconds of cord occlusion, with animals showing an abrupt flattening of the electrocorticogram. In >90% of instances the first identifiable state after cord release was the high-voltage non-rapid-eye-movement state. There was no apparent change in this response through the 4 days of the study. For experimental group animals the mean percentages of time spent in low-voltage electrocortical state (from 53 +/- 2 to 36 +/- 2), electro-ocular state (from 45 +/- 3 to 28 +/- 3), and fetal breathing activity (22 +/- 4 to 12 +/- 3) were significantly decreased (P <.001) during occlusion hours with respect to nonocclusion hours.

CONCLUSION

Intermittent umbilical cord occlusion with severe but limited hypoxemia and no cumulative acidosis in the near-term ovine fetus disrupts behavioral state activity, with a flattening of the electrocortical activity during occlusions and an overall decrease in the prominence of the low-voltage rapid-eye-movement state. If such insults are frequent and severe enough, they might have an effect on growth and development of the brain during the perinatal period.

Low efficiency of oxygen utilization during exercise in hyperthyroidism

STUDY OBJECTIVE

The mechanism of exercise intolerance in hyperthyroidism has not been fully elucidated. This study was undertaken to determine if hyperthyroidism reduced the efficiency of sub-maximal exercise.

STUDY DESIGN

We measured cardiorespiratory variables up to the anaerobic threshold (AT) during ramp-loading cycle ergometry in 12 patients (New York Heart Association functional class II or III). Studies were performed in the hyperthyroid state and repeated in the euthyroid state after 10 months of medical treatment. In 10-W steps from rest to the AT, we measured oxygen uptake (VO2) as a measure of total body work rate, and pressure rate product (PRP) as a measure of cardiac work rate. Loading watts at AT divided by the increment of Vo2 from rest to the AT (delta Watt/delta VO2) was calculated as an index of work efficiency (where delta means the increment of each value from rest to the AT).

RESULTS

VO2 and PRP at the AT were not significantly different between hyperthyroid and euthyroid states (VO2, 16.6 +/- 3.0 vs 17.5 +/- 2.3 mL/min/kg; PRP, 229 +/- 41 vs 218 +/- 28 x 10(2) mm Hg/min). However, loading watts at the AT were significantly lower in the hyperthyroid than the euthyroid state (28 +/- 22 vs 60 +/- 14 W: p < 0.01). VO2 and PRP while hyperthyroid were significantly higher than when euthyroid at every 10-W step during ramp-loading exercise. Furthermore, delta Watt/delta VO2 was significantly lower in hyperthyroid than euthyroid states (p < 0.001). There was a significant inverse correlation-ship between triiodothyronine and delta Watt/delta Vo2 (r = -0.654, p < 0.001).

CONCLUSION

Hyperthyroidism causes low work efficiency, which may limit exercise tolerance.

Higher plants contain homologs of the bacterial celA genes encoding the catalytic subunit of cellulose synthase

In spite of much effort, no one has succeeded in isolating and characterizing the enzyme(s) responsible for synthesis of cellulose, the major cell wall polymer of plants. We have characterized two cotton (Gossypium hirsutum) cDNA clones and identified one rice (Oryza sativa) cDNA that are homologs of the bacterial celA genes that encode the catalytic subunit of cellulose synthase. Three regions in the deduced amino acid sequences of the plant celA gene products are conserved with respect to the proteins encoded by bacterial celA genes. Within these conserved regions, there are four highly conserved subdomains previously suggested to be critical for catalysis and/or binding of the substrate UDP-glucose (UDP-Glc). An overexpressed DNA segment of the cotton celA1 gene encodes a polypeptide fragment that spans these domains and binds UDP-Glc, while a similar fragment having one of these domains deleted does not. The plant celA genes show little homology at the N- and C-terminal regions and also contain two internal insertions of sequence, one conserved and one hypervariable, that are not found in the bacterial gene sequences. Cotton celA1 and celA2 genes are expressed at high levels during active secondary wall cellulose synthesis in developing cotton fibers. Genomic Southern blot analyses in cotton demonstrate that celA forms a small gene family.

Hyperinflation with intrinsic PEEP and respiratory muscle blood flow

Increased end-expiratory lung volume and intrinsic positive end-expiratory pressure (PEEP) are common in obstructive lung disease, especially during exacerbations or exercise. This loads the respiratory muscles and may also stress the circulatory system, causing a reduction or redistribution of cardiac output. We measured the blood flow to respiratory muscles and systemic organs using colored microspheres in 10 spontaneously breathing anesthetized tracheotomized dogs. Flows during baseline breathing (BL) were compared with those during hyperinflation (HI) induced by a mechanical analogue of airway closure and with those during an inspiratory resistive load (IR) that produced an equivalent increase in inspiratory work and time-integrated transdiaphragmatic pressure. Cardiac output was unchanged during IR (3.19 +/- 0.27 l/min at BL, 3.09 +/- 0.34 l/min during IR) but was reduced during HI (2.14 +/- 0.29 l/min; P < 0.01). Among the organs studied, flow was unaltered by IR but decreased to the liver and pancreas and increased to the brain during HI. For the respiratory muscles, flow to the diaphragm increased during IR. However, despite a 1.9-fold increase in inspiratory work per minute and a 2.5-fold increase in integrated transdiaphragmatic pressure during HI, blood flow to the diaphragm was unchanged and flow to the scalenes and sternomastoid fell. The only respiratory muscle to which flow increased during HI was the transversus abdominis, an expiratory muscle. We conclude that the circulatory effects of hyperinflation in this model impair inspiratory muscle perfusion and speculate that this may contribute to respiratory muscle dysfunction in hyperinflated states.

Endomyocardial gene expression during development of pacing tachycardia-induced heart failure in the dog

Selective and specific changes in gene expression characterize the end-stage failing heart. However, the pattern and relation of these changes to evolving systolic and diastolic dysfunction during development of heart failure remains undefined. In the present study, we assessed steady-state levels of mRNAs encoding a group of cardiac proteins during the early development of left ventricular dysfunction in dogs with pacing-induced cardiomyopathy. Corresponding hemodynamic assessments were made in the conscious state in the same animals and at the same time points at baseline, after 1 week of ventricular pacing, and at the onset of clinical heart failure. Systolic dysfunction dominated after 1 week of pacing, whereas diastolic dysfunction was far more pronounced with the onset of heart failure. Atrial natriuretic factor mRNA was undetectable in 7 of 12 hearts at baseline but was expressed in all hearts at 1 week (P < .01 by chi 2 test), and it increased markedly with progression to failure (P = .05). Creatine kinase-B mRNA also rose markedly with heart failure (P < .01). Levels of mRNA encoding beta-myosin heavy chain, mitochondrial creatine kinase, phospholamban, and sarcoplasmic reticulum Ca(2+)-ATPase did not significantly change from baseline, despite development of heart failure. Additional analysis to determine if these mRNA changes were related to the severity of diastolic or systolic dysfunction revealed that phospholamban mRNA decreased in hearts with larger net increases in end-diastolic pressure (+19.2 +/- 1.9 mm Hg) compared with those hearts in which it did not change (+4.0 +/- 4.9, P < .02).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of hyperinflation and CPAP on work of breathing and respiratory failure in dogs

Increased end-expiratory lung volume (EELV) and airway resistance are both characteristic features of obstructive lung disease. Increased EELV alone loads the respiratory muscles and may cause respiratory failure, changes that could be reversed by continuous positive airway pressure (CPAP). To study the effects of elevated EELV on respiration without increased airway resistance, we used a mechanical analogue of airway closure to increase EELV in six spontaneously breathing anesthetized dogs. Hyperinflation of 0.84 +/- 0.11 liter for 30 min decreased minute ventilation from 4.8 +/- 0.37 to 3.5 +/- 0.21 l/min and increased arterial PCO2 from 40.3 +/- 1.5 to 73.2 +/- 8.1 Torr (both P < 0.01). Inspiratory work per breath increased 3-fold, work per liter increased 3.7-fold, and work per minute increased 2.8-fold (all P < 0.01). CPAP at 15 cmH2O restored minute ventilation to 4.3 +/- 0.3 l/min and reduced arterial PCO2 to 54 +/- 6.6 Torr (NS vs. baseline). All measurements of inspiratory work were also restored to baseline, but cardiac output was reduced (baseline 3.09 +/- 0.36, hyperinflation 2.71 +/- 0.36, hyperinflation + CPAP 1.94 +/- 0.29 l/min; P < 0.05, baseline vs. hyperinflation + CPAP). We conclude that increases in EELV mimic important features of airway obstruction, increase inspiratory work, and can cause respiratory failure independent of increased airway resistance. This respiratory failure is reversed by CPAP at the potential expense of hemodynamic compromise.

Synergism between CACGTG (G-box) and CACCTG cis-elements is required for activation of the bean seed storage protein beta-phaseolin gene

Expression of bean seed storage protein phaseolin is under strict developmental control. Four distinct nuclear proteins recognize in vitro the proximal beta-phaseolin promoter (-295/+45) which confers spatial and temporal regulation of the native gene. Functional significance of these protein-binding sites was evaluated by substitution mutation of the motifs in the promoter, which was fused to GUS reporter gene, and subsequent transient gene expression assay using protoplasts from developing bean cotyledons. DNA-binding protein CAN binds three CANNTG motifs, CACGTG (-248/-243), CACCTG (-163/-158), and CATATG (-100/-95). Substitution mutation of the CACGTG motif, which is commonly known as G-box, reduced the -295 promoter activity by 75%, indicating that the G-box is a major positive cis-element. Mutation analyses also demonstrated that the CACCTG and CATATG motifs act as positive and negative cis-elements, respectively. Substitution mutation of all three CANNTG motifs essentially eliminated the -295 promoter activity. A construct containing the G-box and CACCTG motif resulted in a transcriptional level that is much greater than the sum of the transcriptional levels from the individual cis-elements, demonstrating that the G-box and CACCTG act synergistically. Substitution mutations of two AT-rich sequences, to which a nuclear protein AG-1 binds, showed that these sites function as major negative (-376/-367, -356/-347) or positive (-191/-182) cis-elements, and that the effect of the two AG-1 binding sites was counteractive in the -391 promoter. These results indicate that the three CANNTG motifs and two AG-1-binding sites play critical roles in transcription of the beta-phaseolin gene in cotyledons.

5' distal and proximal cis-acting regulator elements are required for developmental control of a rice seed storage protein glutelin gene

Using a homologous transgenic rice system it is demonstrated that 5' distal and proximal cis-acting transcriptional regulatory elements are required for developmental control of a rice seed storage protein glutelin gene. Analyses of gene expression of nine progressively truncated 5' promoter sequences in developing endosperm indicated the existence of at least one major positive element located from the -5.1 to -1.8 kb region. The functional importance of proximal elements in the context of 1.8 kb promoter was demonstrated by single substitution mutations in the TATA box (-28/-23), AACA motif (-73/-61), and protein-binding boxes I (-103/-86), II (-124/-110), III (-175/-158) and IV (-200/-217). A simultaneous mutation of five protein-binding sites (-410/-86) essentially eliminated the activity of the 1.8 kb promoter. Although temporal control of the Gt1 gene during endosperm development was retained in plants of constructs from -5.1 kb to -155 bp, spatial control of the glutelin gene was altered when the 5.1 kb promoter was deleted to -507 bp or -154 bp as the reporter gene activities of these constructs were detected in phloem of leaves, and in stems, sheaths and roots of plants.

[The acute and chronic effects of bunazosin on exercise capacity estimated by the anaerobic threshold in patients with chronic congestive heart failure]

To study the effect of bunazosin on exercise capacity in patients with congestive heart failure (NYHA II-III), anaerobic thresholds (AT, VO2, ml/min/kg) were measured before (control) and after initial 1 = 2mg administration of bunazosin (acute phase; N = 14) and after two weeks of bunazosin therapy (3mg/day, 1mg t. i. d., chronic phase; N = 6). AT were determined by Wasserman's V-slope method during ergometer exercise test with a ramp loading (10 watt/min). AT increased significantly from control during both acute (14.2 +/- 2.7 to 16.9 +/- 3.6 ml/min/kg p < 0.005) and chronic (13.6 +/- 2.5 to 16.7 +/- 1.0 p < 0.05) phase. Additionally, work (watt) attained at AT increased significantly from control during both acute (33.6 +/- 19.2 to 52.6 +/- 30.2 p < 0.005) and chronic (35.8 +/- 25 to 49.3 +/- 15 p < 0.05) phase. Pressure-rate-products (PRP, x 10(2) mmHg/min) at AT increased significantly from control during the acute phase (119 +/- 35 to 240 +/- 50 p < 0.005) alone. In the chronic phase, PRP decreased significantly at the work level equal to AT during control (from 207 +/- 41 to 187 +/- 39 p < 0.05). These data suggest that bunazosin has favorable acute and chronic effects on exercise capacity in patients with congestive heart failure.

Accelerated purine nucleotide degradation by anaerobic but not by aerobic ergometer muscle exercise

The exact conditions under which exercise causes purine nucleotide degradation are not well understood. We determined plasma hypoxanthine and uric acid levels serially in eight individuals during ergometer muscle exercise. When the load was increased gradually by 15 W/min, plasma hypoxanthine was elevated only after the status exceeded the anaerobic threshold (AT), as determined by analysis of expired gas. Nonstrenuous ergometer exercise, which kept the status continuously below the AT, induced neither blood lactic acid nor plasma hypoxanthine elevation. These results suggest that the AT is also the threshold for the acceleration of purine nucleotide degradation. Muscle exercise to a degree that does not exceed the AT does not cause major purine nucleotide degradation, and, therefore, is expected to be beneficial for patients with gout and/or hyperuricemia.

Transposition of the maize activator element in transgenic rice plants

Transposition of the maize Activator (Ac) element was observed in transgenic rice. After protoplast transformation, Ac excision from an interrupted hygromycin phosphotransferase gene was monitored by appearance of the hygromycin-resistant colonies. The frequency of Ac excision, based on the biological assay was up to 19%. Southern hybridization analysis indicated that at least one copy per genome of the hygromycin-resistance gene was reconstituted after Ac excision and that the transposed Ac element was reintegrated into the rice genome. Analysis of DNA sequences at 14 empty donor sites indicated that the Ac element was excised in rice in a similar manner as maize. The excision of an Ac mutant in which a 1.3 kbp Tn903 fragment was inserted at a unique BamHI site so as to disrupt binding of the putative transposase was not detected by DNA analysis. These results demonstrated that the maize Ac element might be used as an effective heterologous transposon for mutagenesis and gene tagging in rice, an important food crops.

Chloroplast DNA evolution in potato (Solanum tuberosum L.)

A deletion specific to chloroplast (ct) DNA of potato (Solanum tuberosum ssp. tuberosum) was determined by comparative sequence analysis. The deletion was 241 bp in size, and was not flanked by direct repeats. Five small, open reading frames were found in the corresponding regions of ctDNAs from wild potato (S. tuberosum ssp. andigena) and tomato (Lycopersicon esculentum). Comparison of the sequences of 1.35-kbp HaeIII ctDNA fragments from potato, tomato, and tobacco (Nicotiana tabacum) revealed the following: the locations of the 5' ends of both rubisco large subunit (rbcL) and ATPase beta subunit (atpβ) mRNAs were probably the same as those of spinach (Spinacia oleracea); the promoter regions of the two genes were highly conserved among the four species; and the 5' untranslated regions diverged at high rates. A phylogenetic tree for the three potato cultivars, one tomato cultivar, and one tobacco cultivar has been constructed by the maximum parsimony method from DNA sequence data, demonstrating that the rate of nucleotide substitution in potato ctDNA is much slower than that in tomato ctDNA. This fact might be due to the differences in the method of propagation between the two crops.

[A study on tooth preparation by means of the newly developed parallelometer and its educational effect, with primary regard to convergence angles of abutment tooth]

Proper tooth preparation is one of the fundamental requirements in crown & bridge prosthodontics. However, it is difficult for students in particular to prepare adequate convergence angles of abutment tooth in the limited environment of patient's mouth. Therefore, the parallelometer was developed to improve the preparations as a supplementary device which informs the person by a signal of alarming simultaneously when a bur is not properly installed to convergence angles of abutment tooth. Sixty subjects were selected from students of Kanagawa Dental College and they were divided into two groups (A and B) to prepare abutment tooth of lower right 1st molar for full cast crown on typodont mounted into the manikin. A preliminary training was performed for once without the parallelometer for group A and with it for group B prior to a comparative experiment. The following results were obtained with primary regard to convergence angles of abutment tooth. 1. Related to each of four convergence angles, group B is superior to group A in all mean values with a statistical significance (P less than 0.01). 2. Related to a total of four convergence angles by the maximum number of subjects, group B is also superior to group A in a mean value by about ten degrees. 3. A newly developed parallelometer proved to be an efficient supplementary device for training of students to master a technique of preparation for adequate abutment tooth.

Reduction in pulmonary varix size after mitral valve replacement

A 48-year-old female was admitted to our hospital for examination of an abnormal shadow in the right lung field. She had a systolic murmur (4/6) over the apex and the chest radiograph revealed cardiac enlargement with three round opacities in the right lung field. Cardiac catheterization showed marked mitral regurgitation and large pulmonary varices. Pulmonary varix caused by mitral regurgitation was diagnosed. The size of the pulmonary varix was reduced with improvement of pulmonary artery wedge pressure one month after mitral valve replacement. We conclude that pulmonary varices can decrease in size secondary to lowering of left atrial pressure within one month after operation.

Abnormal breathing patterns in patients with mitral stenosis: a possible compensatory role

The breathing patterns of 37 patients with mitral stenosis were investigated in standing position by Konno-Mead analysis. Hemodynamic parameters were measured by cardiac catheterization, pulmonary function variables by pulmonary function testings and distribution of pulmonary perfusion by Tc-99m-MAA scintigraphy. Seventeen patients displayed rib cage dominant breathing patterns, and 6 patients displayed paradoxical breathing patterns, whereas 14 patients displayed normal breathing patterns. None of these patients exhibited an abdomen dominant breathing pattern. The patients with abnormal breathing patterns (rib cage dominant or paradoxical) displayed significantly higher values of pulmonary arterial pressure (p less than 0.01), capillary wedge pressure (p less than 0.01), total pulmonary vascular resistance (p less than 0.01) and mitral valve gradient (p less than 0.05) as well as smaller mitral valve area (p less than 0.05) and lower values of both in PaO2 (p less than 0.05) and diffusing capacity (p less than 0.05) than patients with normal breathing patterns. Abnormal distribution of pulmonary perfusion with hyperperfusion in the upper zone of the lung were found to be associated with the abnormal breathing patterns. Since rib cage dominant and paradoxical breathing patterns are known to increase ventilation in the upper zone of the lung, these abnormal breathing patterns may represent a compensatory mechanism serving to match ventilation and perfusion.

[Utility of digital perfusion images of the lung in mitral stenosis: the pathophysiological significance of the distribution of pulmonary perfusion]

The relationship between pulmonary hemodynamics (cardiac index; CI and the mean pulmonary artery wedge pressure; mPw) and the redistribution of pulmonary perfusion were studied in 300 patients with mitral stenosis using computerized Tc99m-MAA perfusion images (digital perfusion images: DPI), which consisted of isocount areas. Various types of DPI were obtained and were classified in six grades according to patterns of 100-70% of the isocount area in the right anterior DPI, i.e. grade-0 (normal), grade-1 (increased perfusion in the upper zone), grade-2 (uniform distribution), grade-3 (disappearance of the basal hyperperfusion area), grade-4 (apical hyperperfusion area) and grade-5 (decrease of perfusion at the lower zone). The mPw was thought to be one of the factors determining distribution. Thus, it was not adequate to estimate the mPw from DPI. In patients with the mPw less than 20 mmHg, an increase in perfusion at the upper zone and disappearance of the basal hyperperfusion might be noted, however, the mPw more than 20 mmHg was necessary to cause an apical hyperperfusion area. The predictive values of grades 0 and 1 for the mPw less than 20 mmHg were 70% (54/77) and those of grades 4 and 5 for the mPw less than 20 mmHg and the mPw less than 25 mmHg were 86% (110/128) and 56% (71/128), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Positive inotropic action of saponins on isolated atrial and papillary muscles from the guinea-pig

The effects of several saponins of animal and plant origin on the contractile activity of atrial and papillary muscles of the guinea-pig were tested. In a concentration of 1 X 10(-5)M, holothurin-A (HL-A), holothurin-B, echinoside-A, echinoside-B and sakuraso-saponin (Saku) exhibited positive inotropic and chronotropic actions whereas desacyl-jego-saponin and ginsenoside-Rd did not. Saponins having a positive inotropic action caused haemolysis of rabbit erythrocytes whereas those without inotropic action did not cause haemolysis. The positive inotropic action of saponins was not affected by practolol, chlorpheniramine, cimetidine and indomethacin. Verapamil (10(-6)M) inhibited the inotropic actions due to HL-A and isoprenaline (10(-8)M) to the same extent but had a small effect on those due to ouabain (10(-7)M). In high K+ (30 mM K+) medium where the action potential and the contraction were depressed, HL-A, Saku and isoprenaline restored the action potential and the contraction of the 'slow response' type whereas ouabain failed to do so. In normal medium HL-A and Saku reduced the resting membrane potential by 15-20 mV. These results suggest that modification of the Ca channel is involved in the positive inotropic action of saponins.

[Transient obstruction of the left ventricular outflow tract induced by excessive alcohol intake: a case report]

A case of transient obstruction of the left ventricular outflow tract after excessive intake of alcohol was reported. This 41-year-old man was admitted to the Hiroo Hospital because of a syncopal attack experienced while walking. He had been drinking excessively for one week until the day before admission. On admission, physical examination revealed a bifid carotid pulse and a grade 3/6 systolic ejection murmur accentuated by Valsalva maneuvers and prompt standing. The second heart sound was paradoxically split. Echocardiography showed typical systolic anterior motion of the mitral valve (SAM). The interventricular septal and left ventricular posterior wall thicknesses were 13 mm and 11 mm, respectively. No enlargement or displacement of the papillary muscles was noted. The redundant mitral chordae tendineae protruded into the left ventricular outflow tract in systole, and both the anterior and posterior mitral valve leaflets were retracted upwards approximating the interventricular septum by these chordae, resulting in obstruction of the left ventricular outflow tract. All signs of left ventricular outflow obstruction, including SAM, disappeared within several days after admission, and prolapse of the anterior mitral leaflet became evident. Since ejection fraction was markedly increased and the corrected QT interval was prolonged on admission, this patient was considered to be in hyperadrenergic state induced by excessive alcohol intake. In this case, left ventricular outflow tract obstruction was attributed to hyperadrenergic state and a redundant mitral apparatus.