Correlation between magnesium pre-loading and cisplatin-induced nephrotoxicity in 5-fluorouracil/cisplatin combination therapy for esophageal cancer

The use of cisplatin may cause nephrotoxicity in patients. Hydration solutions supplemented with magnesium could reduce cisplatin-induced nephrotoxicity. In this study, we evaluated the preventive effect of magnesium pre-loading on cisplatin-induced nephrotoxicity in patients with esophageal cancer. We retrospectively evaluated the prevalence of, and risk factors for, nephrotoxicity in 160 patients with esophageal cancer treated with the 5-fluorouracil/cisplatin regimen from 2014 to 2016 with and without magnesium supplementation. Significant differences were observed between the magnesium and non-magnesium groups in terms of frequency of estimated creatinine clearance of grade 2 or higher that was at 4% (n = 3) and 13% (n = 10) (p = 0.027), respectively. The logistic regression analysis revealed that eCcr of grade 2 or higher was significantly associated with the non-magnesium regimen (odds ratio (OR), 4.175; 95% confidence interval (CI) = 1.061-16.430; p = 0.041) and age ≥ 65 years (OR, 13.951; 95% CI = 1.723-112.974; p = 0.014). This study suggests that 20 mEq magnesium pre-loading significantly reduces the prevalence of cisplatin-induced nephrotoxicity. Furthermore, when cisplatin is administered to individuals older than 64 years, a close observation for the onset of cisplatin-induced nephrotoxicity is crucial.

Differential impact of renal function on the diagnostic performance of resting full-cycle ratio as non-hyperemic physiological assessment

Background

Fractional flow reserve (FFR) is a gold standard method to evaluate functional lesion severity in daily clinical practice. Recently, the resting full-cycle ratio (RFR) was Previous studies showed the better diagnostic performance of RFR comparing with FFR. It is well known that patients with chronic kidney disease (CKD) have poor prognosis. Therefore, we should carefully assess the functional lesion severity in CKD patients. However, it is unclear whether the diagnostic performance of RFR for detecting functional ischemia is similar regardless of the degree of renal function. The aim of this study is to compare the diagnostic performance of RFR based on renal function.

Method

This study was a prospectively enrolled observational study. A total of 265 consecutive patients with 373 intermediate lesions were enrolled in this study. There were classified into three groups according to renal function (Group 1: eGFR ≥60 mL/min/1.73m2; Group 2: 30 mL/min/1.73m2 ≤eGFR <60 mL/min/1.73m2; Group 3: eGFR <30mL/min/1.73m2). The RFR was measured after adequately waiting for stable condition, while FFR was measured after intravenous administration of ATP (180mcg/kg/min). The discordance between FFR and RFR were assessed the data using known cutoffs for FFR (≤0.80) and RFR (≤0.89).

Results

Of 373 lesions, the median age was 70.1±11.0 years. Functional significance was observed in 153 lesions (41.0%) of all lesions. RFR showed a significant correlation with FFR in each group (Group 1; r2=0.63 [p<0.001], Group 2: r2=0.67 [p<0.001], Group 3: r2=0.51 [p<0.001], respectively). The ROC curve analysis of RFR showed differential results for predicting functional significance (Group 1: AUC 0.88, cut-off value 0.91; Group 2: AUC 0.88, cut-off value 0.89; Group 3: AUC 0.81, cut-off value 0.83; respectively) in each group. The prevalence of discordant between RFR and FFR was significantly different among 3 groups (Group 1: 16.5%, Group 2: 19.4%, Group 3: 25.0%, respectively, p<0.05 for among 3 groups).

Conclusion

The diagnostic performance of RFR was different based on renal function. During RFR acquisition, the degree of renal function could influence concordance with FFR, and should be taken into account when interpreting RFR.

Funding Acknowledgement

Type of funding sources: None.

Differential impact of target vessel on the diagnostic performance of resting full-cycle ratio as non-hyperemic physiological assessment

Background

Recently, wire-based resting indices have been recognized as gold standard for evaluating physiological lesion assessment. The resting full-cycle ratio (RFR) is a unique resting index which is calculated as the point of absolutely lowest distal pressure to aortic pressure during entire cardiac cycle. It is unclear whether the diagnostic performance of RFR for detecting functional coronary artery stenosis is similar in each coronary artery. The aim of this study is to compare the diagnostic performance of RFR based on target coronary vessel.

Method

This study was a prospectively enrolled observational study. A total of 156 consecutive patients with 220 intermediate lesions were enrolled in this study. The RFR was measured after adequately waiting for stable condition, while FFR was measured after intravenous administration of ATP (180mcg/kg/min). Lesions with FFR ≤0.80 were considered functionally significant coronary artery stenosis.

Results

In all lesions, reference diameter, diameter stenosis, lesion length, RFR, and FFR were 3.0±0.7mm, 45±13%, 13.0±8.8mm, 0.90±0.09, and 0.82±0.10, respectively. Functional significance was observed in 88 lesions (40%) of all lesions. RFR showed a significant correlation with FFR in overall lesions (r=0.774, p<0.001). The ROC curve analysis of RFR showed good accuracy for predicting functional significance (AUC 0.87, diagnostic accuracy 81%) in all subjects. Regarding each target vessel, there were similar and significant positive correlation between RFR and FFR (LAD; r=0.733, p<0.001, LCX; r=0.771, p<0.001, RCA; r=0.769, p<0.001, respectively). The prevalence of discordant between RFR and FFR was significantly different among 3 vessels (LAD 26%, LCX 12%, RCA 13%, respectively, p<0.05 for among 3 groups). Regarding the comparison of ROC curves according to lesion location, AUC was significantly lower in LAD than in LCX and RCA (LAD 0.780, LCX 0.947, RCA 0.926, p<0.01 for LAD compared to LCX, p<0.01 for LAD compared to RCA, respectively). Furthermore, the diagnostic accuracy was significantly different according to target vessel (LAD 74%, LCX 88%, RCA 87%, respectively, p<0.05 for among 3 vessels).

Conclusion

RFR demonstrated better diagnostic accuracy for evaluating functional lesion severity. The diagnostic performance of RFR was different based on target vessel. RFR is a unique and useful resting index, and it may detect functionally significant coronary stenosis that cannot be detected with other resting indices in daily practice.

Funding Acknowledgement

Type of funding source: None

Discordance predictor between fractional flow reserve and resting full-cycle ratio in clinical characteristics

Introduction

Fractional flow reserve (FFR) is a gold standard method to evaluate functional lesion severity in daily clinical practice. Recently, the resting full-cycle ratio (RFR) which was newly developed resting indices was launched. Unlike other resting indices evaluated in diastolic phase, RFR is evaluated during entire cardiac phase. Previous studies showed discordance predictors between FFR and instantaneous wave-free ratio. However, it is previously unreported what predictor cause discordant outcome between FFR and RFR.

Purpose

The purpose of this study was to evaluate clinical predictors of discordance between FFR and RFR.

Methods

A total of 156 patients with 220 lesions were prospectively enrolled in this study. RFR was evaluated before inducing hyperemia. FFR was measured after intravenous adenosine triphosphate administration (180 mcg/kg/min). According to FFR and RFR values, the patients and lesions were classified into 4 groups: Concordant negative (Group-1 [n=114]: FFR >0.80, RFR >0.89); negative FFR and positive RFR (Group-2 [n=18]: FFR >0.80, RFR ≤0.89); positive FFR and negative RFR (Group-3 [n=25]: FFR ≤0.80, RFR >0.89); Concordant positive (Group-4 [n=63]: FFR ≤0.80, RFR ≤0.89). Among them, discordance predictors with clinical characteristics between RFR and FFR were compared using by two separate logistic regression analyses. (Group-1 vs. Group-2, Group-3 vs. Group-4, respectively). Age, sex and those predictors with a p value ≤0.10 were included in a multivariate regression analysis using by forward stepwise selection to identify independent predictors of discordance.

Results

On multiple regression analysis, hemodialysis (HD) (OR:6.072 [1.090–33.836]), peripheral artery disease (PAD) (OR:9.053 [1.776–46.162]) and left anterior descending artery (LAD) (OR:9.264 [2.092–41.031]) were significantly associated with positive RFR among negative FFR groups (Groupe 2 discordance). Conversely, diabetes mellitus (DM) (OR:0.212 [0.062–0.721]) and Hb (OR:1.480 [1.102–1.987]) were significantly associated with negative RFR among positive FFR groups (Groupe 3 discordance)

Conclusions

Since the clinical characteristics with HD, PAD, LAD, DM and Hb may influence concordant with FFR during RFR evaluation, it should be considered when interpreting RFR.

Distribution and independent predictors

Funding Acknowledgement

Type of funding source: None

Characterizing learning by simultaneous analysis of continuous and binary measures of performance

Continuous observations, such as reaction and run times, and binary observations, such as correct/incorrect responses, are recorded routinely in behavioral learning experiments. Although both types of performance measures are often recorded simultaneously, the two have not been used in combination to evaluate learning. We present a state-space model of learning in which the observation process has simultaneously recorded continuous and binary measures of performance. We use these performance measures simultaneously to estimate the model parameters and the unobserved cognitive state process by maximum likelihood using an approximate expectation maximization (EM) algorithm. We introduce the concept of a reaction-time curve and reformulate our previous definitions of the learning curve, the ideal observer curve, the learning trial and between-trial comparisons of performance in terms of the new model. We illustrate the properties of the new model in an analysis of a simulated learning experiment. In the simulated data analysis, simultaneous use of the two measures of performance provided more credible and accurate estimates of the learning than either measure analyzed separately. We also analyze two actual learning experiments in which the performance of rats and of monkeys was tracked across trials by simultaneously recorded reaction and run times and the correct and incorrect responses. In the analysis of the actual experiments, our algorithm gave a straightforward, efficient way to characterize learning by combining continuous and binary measures of performance. This analysis paradigm has implications for characterizing learning and for the more general problem of combining different data types to characterize the properties of a neural system.

Metabolism of the calmodulin antagonist DY-9760e in animals and humans

The in vitro metabolism of the calmodulin antagonist DY-9760e was investigated using liver microsomes from humans and three other animal species and compared with the in vivo metabolism in rats after intravenous administration of DY-9760e. Seven major metabolites were produced by human liver microsomes by the following metabolic pathways: N-dealkylation, phenyl hydroxylation, O-demethylation and imidazole oxidation. These metabolites were also produced by liver microsomes from monkeys, dogs and rats; additionally, a hydroxylated derivative of the indazole moiety was produced only by rat microsomes. To identify the structures of two imidazole ring metabolites whose authentic compounds could not be obtained, Escherichia coli co-expressing human cytochrome P450 CYP3A4 and NADPH-P450 reductase was used to biosynthesize these metabolites. NMR spectra elucidated the precise structures; oxidation occurred at the imidazole ring, and the subsequent ring-opening resulted in the generation of amide and formylamine groups. Glucuronide conjugates of the hydroxylated and O-demethylated derivatives were major components in rat bile. Therefore, DY-9760e metabolites generated in vitro correspond to the aglycones of the major metabolites observed in rat bile.

97 CLONED CALF PRODUCTION BY AGGREGATION OF SOMATIC CELL NUCLEAR-TRANSFERRED EMBRYOS

A low pregnancy rate and high frequency of abortion are observed in bovine somatic cell cloning. It is suggested that one of the factors is the low cell number of nuclear-transferred (NT) embryos at the blastocyst stage compared with that of in vivo-derived embryos. We reported that aggregation of bovine NT embryos can develop to blastocysts with cell numbers that are equivalent to in vivo-derived embryos (Akagi et al. 2005 Reprod. Fertil. Dev. 17, 162 abst). In this study, we examined the in vivo development of aggregates of NT embryos after embryo transfer (ET). Following culture in serum-starved medium for 5 to 7 days, fibroblast cells were used as donor cells for NT. NT was performed as previously described (Akagi et al. 2003 Mol. Reprod. Dev. 66, 264–272). Eight-cell stage embryos on Day 2 or 16- to 32-cell stage embryos on Day 4 were used for embryo aggregation after removal of the zona pellucida. Three NT embryos were placed into the depression in a drop of TCM-199 with 50 µg mL−1 phytohemagglutinin for 20 min, and NT aggregates were then moved into the depression in a drop of IVD-101 (Akagi et al. 2005). On Day 7 after NT, ET was performed nonsurgically. Results are summarized in Table 1. Pregnancy rates obtained with the aggregated NT embryos tended to be high compared with the single NT embryos. All pregnant cows in the single NT embryos and 6 of 8 pregnant cows in the aggregated NT embryos were aborted within 90 days. One cow carrying an aggregate of 3 Day 2 NT embryos went to term, and one carrying an aggregate of 3 Day 4 NT embryos is still pregnant at more than 7 months. These results demonstrate that aggregates of 3 NT embryos can develop to term in cattle. Table 1.In vivo development of aggregated NT embryos

Impairment of insulin-stimulated GLUT4 translocation in skeletal muscle and adipose tissue in the Tsumura Suzuki obese diabetic mouse: a new genetic animal model of type 2 diabetes

BACKGROUND

In skeletal muscle and adipocytes, insulin-stimulated glucose transport has been known to occur through the translocation of glucose transporter (GLUT) 4 from the intracellular pool to the plasma membrane. The Tsumura Suzuki obese diabetic (TSOD) mouse, a new genetic animal model of type 2 diabetes, develops moderate degrees of obesity and diabetes that are especially apparent in animals more than 11 weeks old. A defect in insulin stimulation of GLUT4 translocation also contributes to the characteristics of type 2 diabetes.

OBJECTIVE

To characterize this mouse further, we examined the alteration in insulin-stimulated GLUT4 translocation in the skeletal muscle and adipose tissue.

METHODS

For glucose and insulin tolerance tests, the mice were given glucose or insulin and blood samples were collected. After isolation of low-density microsomal membrane and plasma membrane from skeletal muscle and adipose tissue, insulin-stimulated translocation of GLUT4 in these TSOD mice was examined by Western blot.

RESULTS AND CONCLUSIONS

TSOD mice showed a significant increase in blood glucose after the glucose load, and exhibited a significantly attenuated decrease in blood glucose concentrations after administration of insulin, compared with that in control Tsumura Suzuki non-obese (TSNO) mice. The insulin-stimulated translocation of GLUT4 from low-density microsomal membranes to plasma membrane was significantly reduced in both skeletal muscle and adipose tissue of TSOD mice. These results indicate that the reduced insulin sensitivity in diabetic TSOD mice is presumably due, at least in part, to the impaired GLUT4 translocation by insulin in both skeletal muscle and adipocytes.

A three-dimensional synthetic metallic crystal composed of single-component molecules

Molecular metals normally require charge transfer between two different chemical species. We prepared crystals of [Ni(tmdt)2] (tmdt, trimethylenetetrathiafulvalenedithiolate) and carried out crystal structure analyses and resistivity measurements. The analyses and measurements revealed that these single-component molecular crystals are metallic from room temperature down to 0.6 kelvin. Ab initio molecular orbital calculations suggested that pi molecular orbitals form conduction bands. The compact molecular arrangement, intermolecular overlap integrals of the highest occupied and lowest unoccupied molecular orbitals, and tight-binding electronic band structure calculation revealed that [Ni(tmdt)2] is a three-dimensional synthetic metal composed of planar molecules.

Connections between anterior inferotemporal cortex and superior temporal sulcus regions in the macaque monkey

We examined the connections between the anterior inferotemporal cortex and the superior temporal sulcus (STS) in the macaque monkey by injecting Phaseolus vulgaris leucoagglutinin (PHA-L) or wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) into the dorsoanterior and ventroanterior subdivisions of TE (TEad and TEav, respectively) and observing the labeled terminals and cell bodies in STS. We found a clear dichotomy in the connections of the rostral part of STS: the injections into TEad resulted in a dense distribution of labeled terminals and cell bodies in the upper bank of rostral STS, whereas labeling was confined to the lower bank and fundus of rostral STS after injections into TEav. The distribution of labeling in the rostral STS was discontinuous from the distribution of labeling surrounding the injection sites: the lower bank of the rostral STS was spared from labeling in the TEad injection cases, and TEad had only sparse distribution in the TEav injection cases. These results revise the classical view that the lower bank of rostral STS is connected with TE, whereas the upper bank of rostral STS is connected with the parietal, prefrontal, and superior temporal regions (Seltzer and Pandya, 1978, 1991, 1994). The upper bank of the rostral STS is called the superior temporal polysensory area (STP), because it was previously found that neurons there respond to auditory, somatosensory, and visual stimuli. The present results thus suggest that the polymodal representation in STP interacts more with information processing in TEad than TEav. It is also suggested that the information processing in the ventral bank of the rostral STS is distinct from that in TEad, and the former more directly interacts with TEav than TEad.

Divergent backward projections from the anterior part of the inferotemporal cortex (area TE) in the macaque

The organization of backward projections from the anterior part of the inferotemporal cortex (area TE) to the posterior part of the inferotemporal cortex (area TEO) was studied in the macaque monkey by using the anterograde tracer Phaseolus vulgaris-leucoagglutinin (PHA-L). The objectives of the study were to investigate this backward projection and to compare it with 1) the backward projections that have been described previously in the early sensory areas and 2) the forward projection from area TEO to area TE. After a single iontophoretic injection of PHA-L into area TE in three monkeys, a dense distribution of labeled terminals was observed in area TEO and in the ventral bank of the superior temporal sulcus (area PITd) that adjoined area TEO. A less dense distribution was observed in areas V4, V2, and V1. Clusters of labeled terminals in areas TEO and PITd extended more than 4 mm along the cortical surface. The forward projections from area TEO to area TE also were studied for comparison by reanalyzing two previous cases (Saleem et al. ¿1993 Cerebral Cortex 3:454-464). These projections (from area TEO to area TE) were more focal than the terminations that occurred in area TEO after injections into area TE. Nine single axons projecting from area TE to areas TEO/PITd were reconstructed through serial sections. These showed variable, complex branching patterns with multiple arbors (1-12). Arbors were localized in layers 1-3 for four axons, in layer 1 for one axon, layers 5 and 6 for two axons, and in both layers 1-3 and layers 5-6 for two axons. Axons with horizontally elongated arbors confined to layer 1 were not predominant. The size of the individual arbors of these axons along their long axes tended to be larger (1.56 +/- 1.24 mm) than those of TEO-to-TE forward axons (<0.6 mm). Thus, the authors conclude that, like other backward systems described to date, those from area TE to areas TEO/PITd are divergent. However, single axons have more variable laminar patterns of terminal distribution than those in the other backward systems.

Microsatellite analysis of the regeneration process of Magnolia obovata Thunb

We analysed the regeneration process of Magnolia obovata using polymorphic microsatellite markers. Eighty-three adult trees standing in a watershed covering an area of 69 ha, and saplings collected from a smaller research plot (6 ha) located at the centre of the watershed were genotyped using microsatellite markers. Among 91 saplings analysed, 24 (26%) had both parents, 31 (34%) had one parent and 36 (40%) had no parent within the watershed. The proportion of genes in saplings inherited from the adults within the watershed was 43%, and therefore 57% were from outside the site, indicating active gene exchange across the watershed area. Average distance between parents and saplings (264.6 +/- 135.3 (SD) m) was significantly smaller than that of pairs randomly chosen between adults and saplings (436.7 +/- 203.0 (SD) m). The distance of pollen movement inferred from the distance between the two parents of each sapling ranged from 3.2 m to 540 m with an average of 131.1 m +/- 121.1 m (SD). Because 34% ( = 31/91) of saplings had only one parent within the watershed, the estimate of average pollen movement must be smaller than the actual one. Long-distance seed dispersal by birds, inbreeding depression and limitation in acceptance of pollen because of the difference of phenology in each individual flower were considered to be the probable causes of large gene exchange across the watershed.

A new mouse model of spontaneous diabetes derived from ddY strain

By the selective breeding of obese male mice of the ddY strain and using indices of the heavy body weight and appearance of urinary glucose, we established two inbred strains in 1992: one with obesity and urinary glucose (Tsumura, Suzuki, Obese Diabetes: TSOD) and the other without them (Tsumura, Suzuki, Non Obesity: TSNO). The male TSOD mice constantly showed signs of obesity and urinary glucose with increases in food and water intake, body weight and some fat weight. The body mass index (BMI) clearly showed moderate obesity. Increases in the levels of diabetic blood parameters (glucose, insulin and lipids) were also found in males, in which the levels of blood glucose and insulin were high to the ages past the growth peak. In the histological studies, pancreatic islets of the TSOD males were found hypertrophic without any signs of insulitis or fibrous formation. Among these diabetic characteristics, some of which were similar to the reported models of non-insulin-dependent diabetes mellitus (NIDDM), the stable appearances of the hyperglycemia, the hyperinsulinemia and the hypertrophy of pancreatic islets to the ages past the growth peak were the prominent features. In these respect the TSOD mouse may be a useful model for researching the mechanisms of human diabetes and its complications.

Genetic analysis of obese diabetes in the TSOD mouse

The molecular pathogenesis of diabetes remains poorly understood because of the genetic complexity of the disease. One possibly effective approach to elucidate the pathogenesis is to study an animal model with a similar phenotype. The TSOD (Tsumura, Suzuki, Obese Diabetes) mouse, a newly developed animal model, exhibits both diabetes and obesity with marked hyperinsulinemia and hypertrophy of the pancreatic islets and might represent a common form of obese type 2 diabetes in humans. Phenotypic characterization revealed that the TSOD mouse had both insulin resistance and impaired glucose-stimulated insulin secretion. A comprehensive genetic dissection of diabetes and obesity has been performed using F1 and F2 progeny between the TSOD and control BALB/cA strains. A genome-wide screen for loci linked to glucose homeostasis and body weight allowed us to map three quantitative trait loci (QTLs) involved in this disorder. The major genetic determinant of blood glucose levels was identified on chromosome 11. Furthermore, two independent QTLs involved in controlling body weight were found on chromosomes 1 and 2. The QTL on chromosome 2 also affected insulin levels significantly. Each QTL has distinct effects on different traits and a different mode of inheritance. Our study indicates that hyperglycemia and obesity are clearly controlled by distinct combinations of genetic loci in this mouse model and provides insights into the genetic basis of common forms of human type 2 diabetes with obesity.

Identification of major biliary and urinary metabolites of ecabapide in rats

1. The structures of major biliary and urinary metabolites of ecabapide in rat were identified by comparison with authentic standards using lc-ms and 1H-nmr spectrometry. 2. A major metabolite was found in the bile obtained from rat after an oral dose of 14C-ecabapide and identified as the amidaldehyde derivative. In the urine, two polar metabolites were characterized as the phenolic sulphates. Further, two lipophilic metabolites were identified as alcohol derivatives, and two others as oxamic acids. 3. From these results, it was estimated that the first step in the metabolism of ecabapide in rat was oxidative N-dealkylation to produce the amidaldehyde. This amidaldehyde was further metabolized by two routes, one by reduction of the amidaldehyde into the corresponding alcohol followed by mono-demethylation and subsequent aromatic O-sulphation, the second by oxidation of the amidaldehyde into the oxamic acid followed by mono-demethylation and subsequent aromatic O-sulphation.

Metabolic activation of CPT-11, 7-ethyl-10-[4-(1-piperidino)-1- piperidino]carbonyloxycamptothecin, a novel antitumor agent, by carboxylesterase

We measured the plasma concentrations of 7-ethyl-10-[4-(1-piperidino)-1- piperidine]carbonyloxycamptothecin (CPT-11) and the active metabolite 7-ethyl-10-hydroxycamptothecin (SN-38), after treatment with CPT-11 to rats pretreated with bis-p-nitrophenylphosphate (BNPP) which is a specific inhibitor of carboxylesterase, and non-pretreated rats. The plasma level of SN-38 was decreased in the BNPP-pretreated group compared with these of non-pretreated group, indicating that the esterase involved in CPT-11 metabolism is a carboxylesterase. We also characterized the molecular species of carboxylesterase involved in CPT-11 metabolism using enzyme preparations purified from liver microsomes. Thirteen carboxylesterase isozyme activities towards CPT-11 were compared and guinea pig GLP1 was found to have the highest activity, while human HU1 isozyme had relatively lower activity than those of animal species. In studies on the kinetic parameters of the hydrolysis of CPT-11 by the purified carboxylesterase isozymes the highest Vmax value of the isozymes was found in human HU1 and the smallest was seen in rat RL1. The Vmax/Km for RL1 showed the largest value of 21.7 nmol/mg protein/mM.

Inhibitory activity of camptothecin derivatives against acetylcholinesterase in dogs and their binding activity to acetylcholine receptors in rats

A camptothecin derivative, 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxycamptothecin (CPT-11), shows a potent antitumour activity in experimental tumour models and in clinical trials. However, CPT-11 induced early diarrhoea and vomiting at high dose levels in clinical studies and showed an acetylcholine-like action on the guinea-pig ileum and trachea. In the present study, we investigated the activities of camptothecin derivatives in inhibiting acetylcholinesterase (AChE) and in binding to muscarinic acetylcholine receptors (AChR). CPT-11 inhibited AChE and binding of the specific ligand to AChR with respective 50% inhibition concentrations of 0.2 and 5 microM. These inhibitions were induced by camptothecin derivatives having an amino group at the C-10 position (or the C-4 position of hexacyclic derivatives), but were not or were only slightly induced by the others. Early defecation and vomiting in dogs were observed after intravenous injection of DU-6596 and DU-6888, two hexacyclic derivatives having the aminomethyl group at the C-4 position, and of CPT-11. DU-6174, however, which has a hydroxy group at this position, induced no early defecation and little vomiting. Plasma concentrations of CPT-11, DU-6596 and DU-6888 after intravenous treatment at doses causing such early adverse effects were maintained for 1 h or longer at levels sufficient to inhibit AChE. These results suggest that the inhibition of AChE by camptothecin derivatives with an amino group at the C-10 position (or the C-4 position) relates to the early defecation or diarrhoea and vomiting.

[Evaluation of lidocaine metabolite (monoethylglycinexylidide) as a liver function test]

In order to determine whether or not the lidocaine metabolism, monoethylglycinexylidide (MEGX) formation, could be used as a liver function test, we measured the serum levels of MEGX in 38 patients. There were significant correlations between values of MEGX (MEGX15, MEGX30, AUC15-30, AUC0-180) and conventional liver function tests (ICG R15, AT III, T. Bil). It appeared that value of MEGX 30 had maximum factor loading on conventional liver function tests by using principal component analysis. The advantage of adapting the MEGX formation as a liver function test of drug metabolism is simplicity of the method. MEGX formation could be useful index of the total liver function.

Lidocaine metabolite formation as a measure of perioperative liver function

In order to determine whether lidocaine metabolism, as the formation of monoethylglycinexylidide (MEGX), could be used as a quantitative index of perioperative liver function, serum levels of MEGX in 31 surgical patients were measured and compared with the results of conventional liver function tests. A significant correlation was found between the values of MEGX and ICGR15 in 20 of the 31 patients. The values of ICGR15 were lower than 20% in patients whose MEGX values were above 60 ng/ml and 20% or higher in those with MEGX values of lower than 60 ng/ml. There was also a significant correlation between MEGX values and antithrombin III values, and between MEGX values and the postoperative maximum levels of aspartate aminotransferase. However, no correlation was found between MEGX values and other preoperative conventional liver function tests in any of the 31 patients. We suggest that a cut-off MEGX value of 60 ng/ml be used as an indicator for satisfactory preoperative liver function. MEGX formation could be a useful prognostic index for patients who have undergone surgical procedures for liver disease, and employed as a quantitative assessment of perioperative liver function.

[Comparison of the amounts of hCG and PMSG to induce ovulation in 50% of the animals, mice, Syrian hamsters and rats]

On the day of diestrus, female mice, syrian hamsters and rats, showing regular 4-day estrous cycles, were injected with hCG or PMSG and were inspected for the presence of ovulation the following day. The dose level expected to cause an effect in 50% of the animals (ED50) was calculated using the Van der Waerden method. When hCG was injected into i. v., i. p. and s. c., the ED50 values per animal and per body weight (kg) in parenthesis were as follows; 0.2 (7.7), 0.3 (11.5) and 0.7 (26.9) I. U. for mice, 1.0 (9.5), 1.8 (17.1) and 2.6 (24.8) I. U. for syrian hamsters and 1.3 (4.6), 3.5 (12.3) and 7.5 (26.3) I. U. for rats, respectively. In PMSG study, the ED50 values per animal and per body weight (kg) in parenthesis were as follows: i. v., 0.8 (30.8); i. p., 2.0 (76.9); s. c., 2.8 (107.7) I. U. for mice, i. v., 3.6 (34.3); i. p., 8.0 (76.2); s. c., 13.2 (125.7) I. U. for syrian hamsters and i. v., 6.0 (76.8); i. p., 20.8 (73.0); s. c., 76.8 (269.5) I. U. for rats, respectively. From these results, the intravenous ED50 value was lower than other routes in three rodents with hCG or PMSG. In all injection routes, the ED50 value for mouse was lower than others. However, there were not significant differences in the ED50 values per body weight (kg) among three rodents. In particular, subcutaneous ED50 of hCG and intraperitoneal ED50 of PMSG were almost same values among three rodents, respectively. Given that the ED50 value per body weight (kg) in one of three rodents is determined, its value may be possible to be extrapolated to remaining two rodents.

Identification of the metabolites of irinotecan, a new derivative of camptothecin, in rat bile and its biliary excretion

1. To investigate the metabolites and biliary excretion of new camptothecin analogue, irinotecan, the drug was administered i.v. to rats (10 mg/kg) and bile, urine and faeces were collected. 2. In rat bile, unchanged irinotecan, the metabolite 7-ethyl-10-hydroxycamptothecin (EHCPT) and unknown metabolite M-1 were found by t.l.c. and h.p.l.c. From beta-glucuronidase hydrolysis, n.m.r. spectrometry and mass spectrometry, M-1 was identified as EHCPT-glucuronide (EHCPT Glu). Other metabolites in the bile were negligible. 3. The cumulative biliary and urinary excretion of radioactivity after dosage of rats with irinotecan were 62.2% and 33.3% dose, respectively, and 9.0% of the radioactivity was excreted in the faeces. 4. Approx. 55% of the biliary radioactivity excreted in 24 h was unchanged irinotecan, 22% was EHCPT Glu, and 9% was EHCPT. 5. Approx. 18% of the biliary radioactivity was reabsorbed from the intestine.

Identification of a dithiol intermediate metabolite of malotilate in rats

1. A chemically unstable dithiol intermediate metabolite of malotilate was identified by g.l.c.-mass spectrometry after conversion of the dithiol to a stable derivative by a cyclization reaction with 1,3-dichloroacetone. The dithiol, namely, 2,2-di(isopropoxycarbonyl)ethylene-1,1-dithiol, was present in rat liver at low concentrations. 2. A study of glucuronidation in vitro indicated that the dithiol was converted to the corresponding thio-glucuronide by rat hepatic microsomal enzymes. 3. It was thus confirmed that metabolism of malotilate proceeds via the dithiol intermediate to form the thio-glucuronide, which is a major metabolic pathway.

Rat epidermal growth factors: purification and tissue content

Rat epidermal growth factor (rEGF) was isolated from the submaxillary gland of male rat by reversed phase high performance liquid chromatography and ion exchange chromatography. The binding of purified rEGF to human carcinoma cells (A-431) and its tritiated thymidine uptake on rat epidermal fibroblast cells (FR) were almost the same as those of purified commercially available mouse EGF (mEGF). Antisera to rEGF was raised in rabbits and a radioimmunoassay (RIA) system was established. The assay range of the RIA was about 1.0 to 100 ng/ml. The within assay coefficients of variation were 5 to 10%, while the between assay coefficients of variation were 5 to 13%. The tissue content of rEGF of male rats (10 weeks old) was examined. As a result, the submaxillary gland was found to contain a very high concentration of rEGF (214 micrograms/g wet tissue) as predicted, and digestive tissues, stomach, intestine and duodenum contained 2.49, 3.57, 9.44 ng/g wet tissue, respectively. The amounts in prostate and seminal vesicle were relatively high, being 65.6 and 2,268 ng/g wet tissue, respectively. The amount in the submaxillary gland increased markedly after 7 weeks of age. These results suggest that EGF is an important factor in gonadal function.

[A simultaneous operation of closure of multiple congenital coronary artery-pulmonary artery fistulas and aortocoronary bypass grafting--a case report]

A 59-year-old male was admitted because of severe chest pain and diagnosed as inferior myocardial infarction by ECG and enzymologically, who had a Levine grade II continuous murmur in the left second intercostal space at the left sternal border. Cardiac catheterization revealed a 8% left to right shunt at pulmonary artery. Selective coronary cineangiography revealed left anterior descending-to-main pulmonary artery and left circumflex-to-main pulmonary artery fistulas, and severe atherosclerotic stenosis at right coronary and left anterior descending arteries. Operation was performed simultaneously, closure of two drainage orifices of the fistulous vessels through pulmonary arteriotomy and aortocoronary bypass grafting to left anterior descending under cardiopulmonary bypass. The postoperative course was uneventful, and the murmur was disappeared.

[Successful surgical treatment of incomplete type IB2 cor triatriatum (absent left innominate vein) with coronary sinus atrial septal defect]

The combination of type IB2 cor triatriatum and coronary sinus ASD is very rare in congenital heart condition. Up to present, only one case of IB2 cor triatriatum and thirteen cases of coronary sinus ASD were reported in Japan. In this combination, we have presented the first successful surgical treatment for type IB2 cor triatriatum (Lucas-Schmidt's classification), absent left innominate vein and coronary sinus ASD. The patient was a 52-year-old female admitted with chronic dyspnea. Echocardiography and cardiac catheterization revealed ASD, severe mitral regurgitation, cor triatriatum, left SVC connected to left atrium (accessory chamber) and absent coronary sinus. Under cardiopulmonary bypass she underwent surgical treatment which consisted of a resection of the intra-left-atrial diaphragm, closure of ASD with patch, mitral valve replacement with Omnicarbon #29 valve and ligation of left SVC. Her postoperative course was uneventful.

Sensitive and selective method for the determination of chlormezanone in plasma by electron-capture gas chromatography

A sensitive and selective determination method of chlormezanone in plasma has been divised. Chlormezanone in plasma was extracted with toluene at pH 4.5, and converted into p-chlorobenzaldehyde in 0.1 N NaOH. Using p-bromobenzaldehyde as an internal standard, the hydrolysis product and the internal standard were extracted with n-hexane, and the extract was concentrated in vacuo in the presence of isoamyl alcohol to prepare the sample solution. The sample solution was submitted to electron-capture gas chromatography. Chlormezanone was determined by use of the peak height ratio of p-chlorobenzaldehyde against the internal standard. The method was utilized successfully for pharmacokinetic studies of chlormezanone in plasma.

Quantitative analysis of oxepinac in human plasma, urine and saliva by gas chromatography--mass fragmentography

A sensitive and specific method is described for the quantitative analysis of 6,11-dihydro-11-oxo-dibenz[b,e]oxepin-3-acetic acid (oxepinac) in human plasma, urine and saliva. Oxepinac and internal standard are extracted from acidified plasma, urine or saliva, converted to the corresponding n-propyl esters and analysed by gas chromatography--mass fragmentography using selected ion monitoring. The method is accurate and precise over the range 100 microgram/ml to 1.0 ng/ml. The method has been applied to the analysis of plasma, urine and saliva from healthy volunteers receiving therapeutic doses of oxepinac.