Serum miR-206 as a biomarker for drug-induced skeletal muscle injury in rats

Creatine kinase (CK) and lactate dehydrogenase (LDH) serve as biomarkers for skeletal muscle injury in preclinical toxicity studies, but have a limitation regarding tissue specificity. Circulating miR-206 was recently reported to be a useful biomarker for skeletal muscle disorders in humans. Here, we sought to determine whether serum miR-206 can be used as a biomarker in preclinical toxicity studies to detect drug-induced skeletal muscle injury with higher sensitivity and specificity than the biomarkers CK, LDH, skeletal troponin I (sTnI), and myosin light chain 3 (Myl3). We established rat models of skeletal muscle injury through treatment with the muscle toxicant 2,3,5,6-tetramethyl-p-phenylenediamine (TMPD) as well as four in-house compounds. We found that serum miR-206 levels significantly increased after treatment with TMPD, and tended to be higher in rats treated with in-house compounds than in control rats. ROC analysis revealed that the specificity of serum miR-206 for detection of skeletal muscle injury was higher compared with those of other markers. Further, serum miR-206 levels were unchanged in rats with isoproterenol-induced cardiotoxicity. These findings demonstrate that serum miR-206 may serve as a highly specific biomarker for preclinical analysis of rats with drug-induced skeletal muscle injuries.

Serum microRNA profiles in patients with chronic hepatitis B, chronic hepatitis C, primary biliary cirrhosis, autoimmune hepatitis, nonalcoholic steatohepatitis, or drug-induced liver injury

PURPOSE

Some blood biomarkers or histological examination by liver biopsy are used for the diagnosis of liver diseases in clinics. However, conventional blood biomarkers show poor specificity and sensitivity, and liver biopsy is highly invasiveness. Therefore, to overcome such disadvantages, specific/sensitive and noninvasive options are desirable. In recent years, circulating microRNAs (miRNAs) have been acknowledged for their potential as disease markers. Actually, several miRNAs have been reported to be biomarker candidates of liver diseases. However, these earlier studies were performed for one disease. Therefore, the specificity as biomarkers was not guaranteed, because they didn't study for the other types of liver injury. In this study, we examined if circulating miRNA could distinguish different types of liver diseases.

METHODS

Serum miRNA profiles in 28 patients with chronic hepatitis B, chronic hepatitis C, primary biliary cirrhosis, autoimmune hepatitis, nonalcoholic steatohepatitis or drug-induced liver injury as well as 4 control subjects were determined by TaqMan MicroRNA Array analysis. Principal component analysis (PCA) of selected miRNAs was performed.

RESULTS

We identified 37 miRNAs whose levels were significantly different between any of the groups. Although individual miRNAs could not distinguish different types of liver diseases, probably because of similar liver pathology, their profiling by PCA could classify different liver disease groups.

CONCLUSIONS

The profiling of the selected miRNAs can be useful to distinguish different types of liver diseases.

Changes in the expression of miRNAs at the pericentral and periportal regions of the rat liver in response to hepatocellular injury: comparison with the changes in the expression of plasma miRNAs

MicroRNAs (miRNAs) in body fluids have received attention as potential biomarkers of organ damage because miRNAs that are highly or specifically expressed in a given organ are likely released into body fluids as a result of damage to that organ. We previously determined that the plasma miRNA profile in rats was dramatically changed due to acetaminophen (APAP)-induced pericentral necrosis and methapyrilene (MP)-induced periportal necrosis in the liver. The purpose of this study was to examine whether the expression of hepatic miRNAs is differentially modulated at different zones due to injury and to examine the relationship of the hepatic miRNA profile with the changes in the plasma miRNA expression profile. Through the laser microdissection of the periportal and periportal regions of the liver and TaqMan microRNA Array analysis, we found that 49 miRNAs are differentially expressed between the pericentral and periportal regions of control rats. In both APAP- and MP-treated rats, the miRNAs that presented decreased expression dominated in both the injured and non-injured areas compared with the miRNAs that exhibited increased expression. The changes in miRNA expression in each region of the liver were compared with those observed in the plasma. Of the 301 plasma miRNAs with expression that was changed as a result of APAP administration, only 21% were changed in the injured area of the liver. Of the 263 plasma miRNAs with expression that was changed due to MP administration, only 24% were changed in the injured area of the liver. Thus, the miRNA expression profiles in the plasma do not merely reflect the release of miRNAs from the damaged cells in the liver. This report provides the first demonstration of zonal miRNA expression in the liver and of the relationship of the miRNA expression profile in a tissue with the plasma miRNA profile.

Plasma microRNA profiles in rat models of hepatocellular injury, cholestasis, and steatosis

MicroRNAs (miRNAs) are small RNA molecules that function to modulate the expression of target genes, playing important roles in a wide range of physiological and pathological processes. The miRNAs in body fluids have received considerable attention as potential biomarkers of various diseases. In this study, we compared the changes of the plasma miRNA expressions by acute liver injury (hepatocellular injury or cholestasis) and chronic liver injury (steatosis, steatohepatitis and fibrosis) using rat models made by the administration of chemicals or special diets. Using miRNA array analysis, we found that the levels of a large number of miRNAs (121-317 miRNAs) were increased over 2-fold and the levels of a small number of miRNAs (6-35 miRNAs) were decreased below 0.5-fold in all models except in a model of cholestasis caused by bile duct ligation. Interestingly, the expression profiles were different between the models, and the hierarchical clustering analysis discriminated between the acute and chronic liver injuries. In addition, miRNAs whose expressions were typically changed in each type of liver injury could be specified. It is notable that, in acute liver injury models, the plasma level of miR-122, the most abundant miRNA in the liver, was more quickly and dramatically increased than the plasma aminotransferase level, reflecting the extent of hepatocellular injury. This study demonstrated that the plasma miRNA profiles could reflect the types of liver injury (e.g. acute/chronic liver injury or hepatocellular injury/cholestasis/steatosis/steatohepatitis/fibrosis) and identified the miRNAs that could be specific and sensitive biomarkers of liver injury.

MicroRNAs regulate human hepatocyte nuclear factor 4alpha, modulating the expression of metabolic enzymes and cell cycle

Hepatocyte nuclear factor (HNF) 4alpha is a key transcription factor regulating endo/xenobiotic-metabolizing enzymes and transporters. We investigated whether microRNAs are involved in the regulation of human HNF4alpha. Potential recognition elements for miR-24 (MRE24) were identified in the coding region and the 3'-untranslated region (3'-UTR), and those for miR-34a (MRE34a) were identified in the 3'-UTR in HNF4alpha mRNA. The HNF4alpha protein level in HepG2 cells was markedly decreased by the overexpression of miR-24 and miR-34a. The HNF4alpha mRNA level was significantly decreased by the overexpression of miR-24 but not by miR-34a. In luciferase analyses in HEK293 cells, the reporter activity of plasmid containing the 3'-UTR of HNF4alpha was significantly decreased by miR-34a. The reporter activity of plasmid containing the HNF4alpha coding region downstream of the luciferase gene was significantly decreased by miR-24. These results suggest that the MRE24 in the coding region and MRE34a in the 3'-UTR are functional in the negative regulation by mRNA degradation and translational repression, respectively. The down-regulation of HNF4alpha by these microRNAs resulted in the decrease of various target genes such as cytochrome P450 7A1 and 8B1 as well as morphological changes and the decrease of the S phase population in HepG2 cells. We also clarified that the expressions of miR-24 and miR-34a were regulated by protein kinase C/mitogen-activated protein kinase and reactive oxygen species pathways, respectively. In conclusion, we found that human HNF4alpha was down-regulated by miR-24 and miR-34a, the expression of which are regulated by cellular stress, affecting the metabolism and cellular biology.

Noninvasive detection of total occlusion of the left anterior descending coronary artery with transthoracic Doppler echocardiography

OBJECTIVES

The purpose of this study was to evaluate the value of transthoracic Doppler echocardiography (TTDE) for the noninvasive detection of total left anterior descending coronary artery (LAD) occlusion.

BACKGROUND

Total coronary occlusion is associated with an adverse long-term prognosis, and mechanical revascularization may be required for the patient with total coronary occlusion. However, a noninvasive diagnosis of total coronary occlusion before coronary angiography (CAG) has been difficult, especially in patients without clinical signs.

METHODS

We studied 103 consecutive patients who underwent CAG for the evaluation of coronary artery disease. The study group consisted of 16 patients with total LAD occlusion (group A) and 87 patients without total LAD occlusion (group B). Coronary flow velocity in the mid-portion of the LAD was recorded by TTDE.

RESULTS

Adequate spectral Doppler recordings of diastolic flow in the LAD were obtained in 98 study patients (95%; 15 patients in group A and 83 patients in group B). In group A, retrograde LAD flow was obtained in 14 (93%) of 15 patients. The mean diastolic velocity of the retrograde flow was 21.0 +/- 6.1 cm/s. In group B, antegrade LAD flow was obtained in all 83 patients (100%). The mean diastolic velocity of the antegrade flow was 21.5 +/- 7.1 cm/s. Retrograde LAD flow by TTDE had a sensitivity of 93% and a specificity of 100% for the detection of total LAD occlusion.

CONCLUSIONS

Retrograde flow in the LAD by TTDE is a highly sensitive and specific finding that can be used to noninvasively diagnose total LAD occlusion.

Influence of the CYP2D6*10 allele on the metabolism of mexiletine by human liver microsomes

AIMS

To study the influence of CYP2D6*10 on the formation of p-hydroxymexiletine (PHM) and hydroxymethylmexiletine (HMM) using microsomes from human liver of known genotypes.

METHODS

Microsomes from human livers of genotype CYP2D6*1/*1 (n = 5), *1/*10 (n = 6) and *10/*10 (n = 6) were used in this study. The formation of PHM and HMM was determined by high-performance liquid chromatography.

RESULTS

The formation rates of PHM and HMM were decreased by more than 50% and 85% in CYP2D6*1/*10 and *10/*10 microsomes, respectively, compared with *1/*1 microsomes.

CONCLUSIONS

The metabolism of mexiletine to form PHM and HMM appears to be impaired to a significant extent in human liver microsomes from hetero- and homozygotes of CYP2D6*10.

Frequencies of CYP2D6 mutant alleles in a normal Japanese population and metabolic activity of dextromethorphan O-demethylation in different CYP2D6 genotypes

AIMS

To determine the frequencies of 11 CYP2D6 mutant alleles (CYP2D6*2, *3, *4, *5, *8, *10, *11, *12, *14, *17 and *18), and their relation to the metabolic capacity of CYP2D6 in Japanese subjects.

METHODS

One hundred and sixty-two unrelated healthy Japanese subjects were genotyped with the polymerase chain reaction amplification method and 35 subjects were phenotyped with dextromethorphan.

RESULTS

The frequencies of CYP2D6*2,*5, *10 and *14 were 12.9, 6.2, 38.6 and 2.2% in our Japanese subjects, respectively. CYP2D6*3, *4, *8, *11, *12, *17 and *18 were not detected. The mean log metabolic ratio of dextromethorphan in subjects with genotypes predicting intermediate metabolizers was significantly greater than that of heterozygotes for functional and defective alleles.

CONCLUSIONS

CYP2D6*5 and CYP2D6*14 are the major defective alleles found in Japanese subjects. In addition, CYP2D6*10 may play a more important role than previously thought for the treatment of Japanese patients with drugs metabolized by CYP2D6.

Evaluation of the mitral annulus by extracted three-dimensional images in patients with an annuloplasty ring

We evaluated the capability of extracted 3-dimensional images obtained by multiplane transesophageal echocardiography in the evaluation of nonplanarity and area change of the mitral annulus in patients with an annuloplasty ring. This method is feasible in the evaluation of nonplanarity and area change of mitral annulus in patients with an annuloplasty ring.

[Serial changes in mitral regurgitation after mitral valve repair with artificial chordae tendineae: assessment by transesophageal echocardiography]

Serial changes in mitral regurgitation after anterior mitral valve repair were examined by transesophageal echocardiography (TEE) in 34 of 86 consecutive patients with pure mitral regurgitation who underwent anterior mitral valve repair from 1987 to 1996. The patients were divided into two groups: 15 patients undergoing mitral repair with polytetrafluoroethylene (PTFE; PTFE group) and 19 undergoing conventional mitral repair without PTFE (non-PTFE group). The PTFE group included 11 men and 4 women with a mean age of 52.1 years. They were followed for mean 22.8 +/- 12.0 months. The non-PTFE group included 12 men and 7 women with a mean age of 53.9 years. They were followed for mean 33.9 +/- 20.4 months. Mitral regurgitation jet areas were observed at the time of operation, 1 month after mitral valve repair, and in the late follow-up period. Regurgitation jet areas were 0.7 +/- 0.7, 1.1 +/- 0.9 and 2.5 +/- 2.1 cm2 in the PTFE group, and 1.1 +/- 1.3, 2.4 +/- 1.7, 4.7 +/- 2.9 cm2 in the non-PTFE group. The jet area was significantly smaller in the PTFE group than in the non-PTFE group at 1 month after operation and in the late follow-up period. Moderate to severe regurgitation was observed in two patients (13.3%) in the PTFE group, and eight patients (42.1%) in the non-PTFE group. Mitral valve repair with PTFE showed better results than conventional mitral valve repair without PTFE during the mean follow-up period of 23 months.

[Long-term results of mitral valve repair with artificial chordae tendineae]

The long-term results of mitral valve repair using artificial polytetrafluorethylene (PTFE) chordae were assessed in 61 consecutive patients with pure mitral regurgitation who underwent mitral valve repair with replacement of elongated or ruptured chordae tendineae between 1992 and 1996. There were 36 men and 25 women aged from 14 to 73 years (mean 52.1 +/- 13.8 years). The patients were followed up for between 1 to 73 months (mean 29.3 +/- 17.6 months). Fifty-five patients underwent mitral valve repair of the anterior leaflet and 6 repair of the posterior leaflet. There were two hospital and two late deaths. Actual survival rate at 5 years was 93.1%. Freedom from cardiac events at 5 years was 87.8%. Two patients required reoperation due to hemolysis. There were three occurrences of non-fatal thromboembolism. Although further investigation is necessary in a large population, expanded PTFE sutures are excellent for chordal replacement during mitral valve repair.

Three-dimensional echocardiographic evaluation of configuration and dynamics of the mitral annulus in patients fitted with an annuloplasty ring

BACKGROUND AND AIMS OF THE STUDY

Three-dimensional (3D) echocardiography permits the objective analysis of structures and of pathologic conditions of complex geometry. Multiplane transesophageal echocardiography (TEE) permits 3D image sets of the heart to be produced from multiple 2D images by rotating the transducer, without changing its position. The purpose of this study was to clarify the capability of 3D echocardiography to evaluate the configuration and dynamics of the mitral annulus in patients fitted with an annuloplasty ring.

METHODS

Twenty patients who underwent mitral valve repair for pure mitral regurgitation (10 with a flexible Duran ring and 10 with a rigid Carpentier ring) were studied. Using a multiplane transesophageal probe, sequential tomographic images were obtained by rotating the transducer at 2 degrees angular intervals around a 180 degrees arc. 3D reconstructions were performed to produce dynamic 3D images of the mitral annulus in a manner that simulated visualization from the left atrium. Mitral annular configuration was assessed from volume-rendered display and extractive 3D imaging. Mitral annular area change was evaluated from selected long-axis cut planes.

RESULTS

The configuration and dynamics of the mitral annulus were visualized by 3D displays. In patients with a Duran ring, the mitral annulus had a non-planar configuration and mitral annular area changed during cardiac cycle (increased in diastole; reduced in atrial and ventricular systole; percentage reduction 25 +/- 2%). In patients with a Carpentier ring, the mitral annulus had a planar configuration and mitral annular area was effectively unchanged during the cardiac cycle.

CONCLUSIONS

3D echocardiography using a multiplane transesophageal probe is useful in evaluating the configuration and dynamics of the mitral annulus in patients fitted with an annuloplasty ring.

[Intraoperative assessment of mitral valve plasty by transesophageal echocardiography]

Mitral valve repair offers many advantages over prosthetic valve replacement, especially in minimizing the risk of thromboembolism. Intraoperative evaluation of residual mitral regurgitation (MR) is important in this procedure. The present study assessed the usefulness of transesophageal echocardiography (TEE) for the intraoperative assessment of residual MR in patients undergoing mitral valve repair. Intraoperative TEE was performed in 102 consecutive patients before and after mitral valve repair in the operating room. The grade of MR was evaluated according to the maximum MR jet area detected by biplane color Doppler TEE (mild: <4 cm2; moderate: 4 < or = < 7 cm2; severe : 7 cm2 < or =). After the first repair, the manual regurgitant test was performed. Excellent results with no or mild MR assessed by the manual regurgitant test were obtained in 101 patients. However, moderate or severe MR was identified in eight of these 101 (7.9%) patients by TEE after weaning from the cardiopulmonary bypass. Consequently, six of these eight patients underwent repeat mitral valve repair and two patients received prosthetic valve replacement. Satisfactory final operative results were obtained in all 101 patients. The eight patients who needed additional operative procedures followed good clinical courses in hospital. TEE 1 month after operation demonstrated no or mild MR in these eight patients. Intraoperative TEE is useful in the evaluation of residual MR after mitral valve repair. This technique provides indications for immediate additional operative procedures, and can reduce the occurrences of congestive heart failure and reoperation in the early stage after mitral valve repair.

[Serial change of mitral regurgitation after anterior mitral valve repair using polytetrafluorethylene chordae: evaluation by transesophageal echocardiography]

The results of anterior mitral leaflet repair were evaluated by the serial change of mitral regurgitation (MR) using transesophageal echocardiography (TEE) in 24 patients undergoing mitral valve repair for anterior leaflet prolapse during 1988 to 1994, who were examined by TEE immediately after operation, 1 month after operation, and late after operation (mean 15 months). Chordal replacement using polytetra-fluorethylene chordae was performed in 15 patients (PTFE group), and not performed in 9 patients (non-PTFE group). MR jet area late after operation was significantly smaller in the PTFE group than in the non-PTFE group (2.2 +/- 2.3 vs. 4.6 +/- 2.3 cm2, p < 0.05). Moderate to severe MR was observed in four patients (27%) in the PTFE group, and six (67%) in the non-PTFE group late after operation. The thickness of the mitral leaflet before operation was more than 5 mm in all patients with more than moderate MR late after operation in the PTFE group. Chordal replacement using polytetrafluorethylene chordae showed better results compared with conventional mitral valve repair without polytetrafluorethylene chordae over the follow-up period of 15 months.

Serial change of mitral regurgitation after mitral valve repair: comparison of anterior with posterior leaflet lesions

Mitral valve repair is an important operative procedure for correcting mitral regurgitation (MR). However, serial change of residual MR after operation has not been reported. Serial change of MR after mitral valve repair was evaluated by transesophageal color Doppler echocardiography (TEE). Twenty-six patients undergoing mitral valve repair for MR during 1987 to 1991 were examined by TEE just after operation, 6 months after operation, and late follow-up period (mean 3.7 years). Thirteen patients had a lesion of the anterior mitral leaflet before operation (group A). Thirteen patients had a lesion of the posterior mitral leaflet before operation (group P). The MR area was measured by TEE at each stage after operation. In group A, the MR area at late follow-up increased significantly compared with just after operation (1.1 vs 4.3 cm2, p < 0.001). In group P, the MR area at late follow-up did not increase significantly compared with just after operation (0.6 vs 1.3 cm2, p = NS). In conclusion, MR does not increase after mitral valve repair in patients with posterior mitral valve repair, but MR may increase at late follow-up after operation for anterior mitral valve prolapse.

Three-dimensional analysis of configuration and dynamics in patients with an annuloplasty ring by multiplane transesophageal echocardiography: comparison between flexible and rigid annuloplasty rings

BACKGROUND AND AIM OF THE STUDY

Multiplane transesophageal echocardiography provides three-dimensional reconstruction of the mitral annulus from multiple cross-sectional views from a stable transducer position by rotating around a central axis. This study was designed to evaluate the effect of the type of annuloplasty ring on mitral annular configuration and dynamics using three-dimensional reconstruction by multiplane transesophageal echocardiography.

METHODS

Ten patients who underwent mitral valve repair for pure mitral regurgitation (five patients with flexible Duran ring, five patients with rigid Carpentier ring) and five normal subjects were studied with multiplane transesophageal echocardiography. Three-dimensional configuration of the mitral annulus was obtained from multiple cross-sectional views of multiplane transesophageal echocardiography.

RESULTS

In normal subjects, the mitral annulus had a non-planar configuration and reduced its area in systole. In patients with a Duran ring, the mitral annulus had a non-planar configuration and reduced its area in systole. In patients with a Carpentier ring, the mitral annulus had a planar configuration and the mitral annular area did not change during the cardiac cycle.

CONCLUSION

Three dimensional reconstruction of the mitral annulus using multiplane transesophageal echocardiography revealed that mitral annular configuration and dynamics are more physiologic in patients with a flexible Duran ring that with a rigid Carpentier ring.

[Mitral valve repair for infectious endocarditis]

Fourteen patients with mitral regurgitation resulting from infectious endocarditis underwent mitral valve repair between December 1988 and July 1994. There were nine males and five females aged from 14 to 70 years (mean 40.2 +/- 19.7 years). Three patients had active endocarditis. Time between the onset of endocarditis symptoms and surgery ranged from 1 to 24 months (mean 8.3 months). Bacterial findings were Streptococcus in eight patients, Staphylococcus in one, and unknown in five. All macroscopically infected tissue was excised in patients with active endocarditis. Carpentier's reconstructive techniques were mainly used. There were no hospital deaths. Mean follow-up was 29 months and complete. Thirteen patients were in New York Heart Association functional class I and one in class II. There were no late deaths, reoperations, recurrent endocarditis, thromboembolic events, or other valve-related morbidity. We conclude that mitral valve repair is an attractive procedure in patients with mitral regurgitation resulting from infectious endocarditis.

Comparison of the Carpentier and Duran prosthetic rings used in mitral reconstruction

This clinical study was undertaken to evaluate the Duran flexible ring and the Carpentier rigid ring in terms of mitral annulus motion, transmitral flow and left ventricular function. Twenty-six patients (11 receiving rigid rings and 15, flexible rings) with normal sinus rhythm and with no or only trivial mitral valve regurgitation after surgical repair were selected. Angiograms demonstrated no significant differences in left ventricular systolic function between the two groups of patients. The area of the mitral annulus with the flexible ring significantly changed during the cardiac cycle. There were significant differences in the left ventricular fractional shortening (rigid ring, 35.8%; flexible ring, 43.4%) and in the peak velocity (rigid ring, 222 cm/s; flexible ring, 186 cm/s) at peak exercise. These data suggest that the flexible ring interferes less with the normal movements of the mitral annulus during the cardiac cycle, and that, under exercise conditions, it performs better than the rigid ring. We therefore conclude that mitral valve reconstruction using the Duran flexible ring is advantageous in patients with mitral regurgitation due to degenerative disease and sinus rhythm.

[Residual, recurrent mitral regurgitation after mitral valve reconstruction: differences in lesion and operation method]

Patients developing residual or recurrent mitral regurgitation (MR) increased to moderate or severe grade after mitral valve reconstruction for MR were investigated by correlating the lesion and operation method with the echocardiographic course of postoperative MR. Postoperative moderate or severe grade MR [more than 4.0 cm2 color Doppler flow area on postoperative transesophageal echocardiography (TEE)] occurred in 21 of 80 mitral valve reconstruction patients. If residual MR caused more than 2.0 cm2 color Doppler flow area on intraoperative TEE, the MR increased to moderate or severe grade during the follow-up period. Postoperative moderate or severe MR occurred more frequently in lesions of the anterior mitral leaflet than the posterior mitral leaflet (45.8% vs 6.5%, p < 0.001), and in elongated chordae than in torn chordae (52.9% vs 14.3%, p < 0.005). Chordal shortening for elongated chordae could correct MR at operation but MR recurred and increased gradually to moderate or severe grade in half of these cases. Chordal reconstruction with polytetrafluorethylene suture is expected to achieve better results than chordal shortening. The causes of postoperative MR could usually be identified by comparative investigation of echocardiographic course, lesion, and operation method. Postoperative moderate or severe MR occurs more often in lesions of the anterior mitral leaflet or cases of elongated chordae. Residual MR should be suppressed to less than 2.0 cm2 color Doppler flow area on intraoperative TEE.

[Diagnosis of sinus venosus atrial septal defect by transesophageal color Doppler and two-dimensional echocardiography]

Diagnosis of sinus venosus atrial septal defect based on transthoracic color Doppler and two-dimensional echocardiography is often difficult. We recently experienced two cases of sinus venosus atrial septal defect which were correctly diagnosed using transesophageal color Doppler and two-dimensional echocardiography. Transthoracic color Doppler flow imaging did not demonstrate the atrial septal defect or the shunt flow across the defect in either case. Transesophageal two-dimensional echocardiography visualized a defect in the upper most portion of the interatrial septum in one case, and transesophageal color Doppler flow mapping detected a left-to-right shunt across the defect in both cases. Transesophageal color Doppler flow mapping also demonstrated the flow signal of the right upper pulmonary vein into the right atrium near its junction with the superior vena cava in each case. The diagnoses of sinus venosus atrial septal defect and combined partial anomalous pulmonary venous return were confirmed by surgery in both cases. Transesophageal color Doppler and two-dimensional echocardiography are very useful in diagnosing sinus venosus atrial septal defect and combined partial anomalous pulmonary venous return.

(R)-1,2,3,4-tetrahydro[1]benzothieno[2,3-c]pyridines: novel optically active compounds with strong 5-HT1A receptor binding ability exhibiting anticonflict activity and lessening of memory impairment

(R)-1,2,3,4-Tetrahydro[1]benzothieno[2,3-c]pyridine derivatives (60-114) were synthesized. The (R)-isomers have affinity for the 5-HT1A receptor while the (S)-isomers have no such ability. The affinity of the (R)-isomers was discussed on the basis of structure-activity relationships between the affinity and hydrophobicity of the (R)-isomers. Compounds 71 and 107, which are representative derivative compounds, have anticonflict activity and lessening of memory impairment. In particular, compound 107 cannot bind to receptors other than the 5-HT1A receptor, demonstrating that it is a unique compound with a different mechanism of action from that of conventional anxiolytics.

Intravascular ultrasound imaging--in vitro and vivo validation

Intravascular ultrasound imaging is a new technique for visualizing arterial structures. The purpose of this study was twofold; first, to assess the ability of this intravascular ultrasound catheter to generate cross-sectional images of human artery segments in vitro and second, to determine the reliability of intravascular ultrasound technique in the evaluation of human arteries in vivo. For the vitro study, ultrasound images of the arteries were presented as a two-dimensional, 360 degrees display of vessel cross-section perpendicular to the long-axis of the probe. The ultrasound scanning provided an accurate description with high resolution of lumen structure and lumen-intima interface in all vessel specimens. There was a good correlation between the planimetric luminal area on the ultrasound images and the area obtained from histologic images (r = 0.92). There was also a good correlation in the plaque thickness between ultrasound and histological examination (r = 0.88). In the in vivo study, the ultrasound catheter was easily introduced, readily manipulated, and images were successfully obtained in all patients. No untoward effects were noted during manipulation of the catheter. There was a good correlation in the arterial dimension between ultrasound and angiographic measurements (r = 0.93). Thus, intravascular ultrasound imaging appears to be useful for characterizing and quantitating arterial lesions.

Effects of mushroom toxins on glycogenolysis; comparison of toxicity of phalloidin, alpha-amanitin and DL-propargylglycine in isolated rat hepatocytes

The effects of phalloidin and alpha-amanitin as toxins of Amanita species and DL-propargylglycine identified from A. abrupta on the glycogenolysis in isolated rat hepatocytes were investigated. Phalloidin decreased glycogen content and activated phosphorylase a activity remarkably. alpha-Amanitin also decreased glycogen content significantly but activated phosphorylase a activity slightly. DL-Propargylglycine slightly affected glycogenolysis. Phalloidin, which most affected glycogenolysis among the three compounds mentioned above, elevated cytosolic Ca2+ concentration ([Ca2+]i) and 45Ca uptake into cells. Phalloidin depressed slightly 3H-inositol incorporation into phosphatidylinositol (PI) and remarkably phosphatidylinositol 4,5-bisphosphate (PIP2) but increased phosphoinositides breakdown. These results suggest that phalloidin alters phosphoinositides turnover and intracellular Ca2+ homeostasis, subsequently activates phosphorylase a, resulting in glycogenolysis in isolated rat hepatocytes.

[Descriptive epidemiology of mushroom poisoning in Japan]

The Incidence of mushroom poisoning was surveyed statistically from 1959 to 1988 in Japan. The results are summarized as follows: 1. During the past three decades, the total number of incidents of mushroom poisoning was 2,096, which involved 10,924 patients and 72 deaths. The average number of incidents was 70 cases per year, involving 364 patients and 2.4 deaths, and the number of incidents decreased gradually every year. Mushroom poisoning usually happened most frequently in September and October. 2. Considering regional differences, the incidence of mushroom poisoning was more frequent in the northeastern part of Japan than in the southwestern part. The incidences of mushroom poisoning in the prefectures of Nagano, Hokkaido, Niigata, Iwate and Fukushima were relatively high. 3. Three species of mushrooms, L. japonicus, R. rhodopolius (R. sinuatus) and T. ustale caused the majority of all poisonings. 4. The rates of total patients and fatalities for each type of poisoning, which were classified according to the symptoms caused, were 90.3% and 10.7% in the type with cholera-like symptoms, 90.2% and 0.2% in that with gastro-intestinal irritation, and 74.1% and 0% in that with neurological symptoms, respectively.

Quantitative structure-activity relationship of catechol derivatives inhibiting 5-lipoxygenase

Various catechol derivatives (beta-substituted 3,4-dihydroxystyrenes, 1-substituted 3,4-dihydroxybenzenes, and 6-substituted 2,3-dihydroxynaphthalenes) were synthesized and their inhibition of 5-lipoxygenase was assayed. Their structure-activity relationships were examined quantitatively with substituent and structural parameters and regression analysis. The variations in the inhibitory activity were explained in bilinear hydrophobic parameter (log P) terms, and steric (molecular thickness) and electronic (proton nuclear magnetic resonance (1H-NMR) chemical shift of the proton adjacent to the catechol group) parameter terms. The hydrophobicity of the inhibitor molecule was important, and the optimum value of logP was about 4.3-4.6, beyond which inhibition did not increase further. A lower electron density of the aromatic ring containing the catechol group and the greater thickness of the lipophilic side chains were unfavorable to the activity. The results added a physicochemical basis for the selection of candidate compounds for developmental studies.

Assessment of aortic regurgitation by the acceleration flow signal void proximal to the leaking orifice in cinemagnetic resonance imaging

BACKGROUND

The proximal acceleration flow region is a laminar flow field that is located immediately upstream from the leaking orifice. The purpose of this study was to evaluate whether cinemagnetic resonance imaging can provide information regarding the proximal acceleration flow region in patients with aortic regurgitation and to analyze the relation between the area of the proximal acceleration flow delineated by cinemagnetic resonance imaging and the severity of aortic regurgitation delineated by angiography.

METHODS AND RESULTS

Thirty-eight consecutive patients who underwent aortography were examined by cinemagnetic resonance imaging. The region of proximal flow acceleration was identified as a semicircular-shaped signal void in the aorta during diastole. Cinemagnetic resonance imaging detected the proximal acceleration flow region in 26 of the 30 patients who were proved to have this lesion (sensitivity, 87%). In eight patients without aortic regurgitation according to aortography, no proximal acceleration flow region was detected (specificity, 100%). The area of the acceleration flow signal void from the long-axis view was well correlated with angiographic degree of aortic regurgitation.

CONCLUSIONS

Cinemagnetic resonance imaging is useful in detecting the proximal acceleration flow region and permits noninvasive assessment of the severity of aortic regurgitation.

Direct visualization of ruptured chordae tendineae by transesophageal two-dimensional echocardiography

To determine the value of transesophageal echocardiography in the detection of ruptured chordae tendineae, 28 patients who had surgical therapy for pure mitral regurgitation were evaluated prospectively by conventional transthoracic and transesophageal two-dimensional echocardiography. Seventeen patients (Group I) had ruptured chordae tendineae and 11 (Group II) had intact chordae tendineae. Transthoracic echocardiography detected ruptured chordae tendineae in 6 patients from Group I (sensitivity 35%) and flail leaflets in 11 patients from Group I (sensitivity 65%). Transesophageal echocardiography disclosed ruptured chordae tendineae in all 17 Group I patients (sensitivity 100%); the sensitivity was significantly higher than that of transthoracic echocardiography. No abnormal chordal echoes were visualized in any patient from Group II by either transthoracic or transesophageal echocardiography (specificity 100%). Transesophageal echocardiography is a highly sensitive method for detecting ruptured chordae tendineae and is superior to transthoracic echocardiography in establishing its diagnosis.

Assessment of mitral regurgitation by biplane transesophageal color Doppler flow mapping

To test the role of recently developed biplane transesophageal color Doppler echocardiography in the assessment of severity of mitral regurgitation, we examined 51 patients undergoing cardiac catheterization and left ventriculography. Transesophageal color Doppler flow imaging detected mitral regurgitation in all 32 patients proved to have this lesion. In 10 of 16 patients without mitral regurgitation by angiography, mitral regurgitation signals were detected by transesophageal color Doppler flow imaging. Thus, the sensitivity and specificity of transesophageal color Doppler echocardiography for the detection of mitral regurgitation were 100% and 38%, respectively. There was some correlation between the regurgitant jet area from the longitudinal plane and angiographic grading. An improved angiographic correlation was achieved with the regurgitant jet area from the transverse plane. The best correlation with angiography was obtained when the maximum regurgitant jet area from two planes (the greater of the two measurements, each from a different plane) was considered. There was a significant difference in the maximum regurgitant jet area between none and mild (p less than 0.01), mild and moderate (p less than 0.001), and moderate and severe (p less than 0.01) mitral regurgitation. The maximum regurgitant jet area of less than 1.5 cm2 predicted the angiographic grading as none with a sensitivity and specificity of 88% and 94%, respectively. The maximum regurgitant jet of between 1.5 and 4 cm2 predicted the angiographic grading as mild with a sensitivity and specificity of 82% and 95%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

In vitro toxicity test of poisonous mushroom extracts with isolated rat hepatocytes

Effects of poisonous mushroom extracts on isolated rat hepatocytes were studied. Though no significant decrease in the cell viability was observed during the incubation of hepatocytes with the extracts at a concentration of 5% (v/v) of Amanita abrupta, A. gymnopus, and A. virosa caused marked decreases in the intracellular glutathione content in sharp contrast to the extracts of A. volvata and A. flavipes. Comparative toxicity tests were carried out for the effects of the extract of A. abrupta, dl-propargylglycine, and alpha-amanitin. The extract of A. abrupta at a concentration of 1% (v/v) caused a marked decrease in the glycogen content, a noticeable elevation in the phosphorylase alpha activity, and a slight acceleration of lipid peroxidation in the hepatocytes. Although dl-propargylglycine decreased the intracellular glutathione content progressively with the incubation time, a significant effect of the chemical on lipid peroxidation and the glycogen content was observed only after prolonged incubation at a concentration of 5 mM. On the other hand, alpha-amanitin exerted a little effect on the hepatocytes at 1 microM. These results have indicated that the intoxication by the extract of A. abrupta on the hepatocytes might not due to independently each component, dl-propargylglycine and alpha-amanitin, but combined effect of these components or unidentified substances.

Detection of left main coronary artery stenosis by transesophageal color Doppler and two-dimensional echocardiography

Although transthoracic two-dimensional echocardiography can detect dilation of the coronary arteries, the reliability of this technique in the detection of coronary artery stenosis is still doubtful. The purpose of this study was to test the ability of newly developed biplane transesophageal color Doppler and two-dimensional echocardiography in the detection of left main coronary artery stenosis. Blood flow in the left main coronary artery was detected in 57 of 67 (85%) patients by transesophageal color Doppler flow imaging. Using transesophageal two-dimensional echocardiography, adequate images of the full length of the left main coronary artery and identification of the bifurcation were obtained in 60 of 67 (90%) patients. Transesophageal echocardiography clearly showed significant (greater than or equal to 50%) narrowing of the coronary lumen in 10 of 11 patients (sensitivity, 91%) and insignificant narrowing or no abnormalities of the coronary lumen in the other 49 patients (specificity, 100%). The positive predictive accuracy for left main coronary artery disease was 100%, and the negative predictive accuracy was 98%. This preliminary study suggests that biplane transesophageal color Doppler and two-dimensional echocardiography appears to be a feasible noninvasive technique for imaging the left main coronary artery and detecting hemodynamically significant luminal obstruction.

Value of acceleration flows and regurgitant jet direction by color Doppler flow mapping in the evaluation of mitral valve prolapse

To clarify the role of color Doppler echocardiography in the evaluation of mitral valve prolapse, we studied 49 consecutive patients in whom the sites of mitral valve prolapse were confirmed at the time of operation. The study group consisted of 22 patients with anterior leaflet prolapse, 24 patients with posterior leaflet prolapse, and three patients with multiple scallop prolapse (one patient with both anterior leaflet and middle scallop prolapse, and two patients with both medial and lateral scallop prolapse). Two-dimensional echocardiographic diagnosis of anterior leaflet prolapse was correct in all patients. The diagnosis of posterior leaflet prolapse by two-dimensional echocardiography, however, was mistaken as anterior leaflet prolapse in 16 (13 patients with medial scallop prolapse and three patients with lateral scallop prolapse) of the 24 patients according to current diagnostic criteria for mitral valve prolapse. Eight patients with middle scallop prolapse were diagnosed correctly by two-dimensional echocardiography. Acceleration flows in the left ventricle were observed by color Doppler echocardiography in all 49 patients. The sites of acceleration flows detected by color Doppler echocardiography coincided with those of prolapse confirmed in all at the time of operation. There was a significant correlation between the maximum area of acceleration flow signals and severity of mitral regurgitation estimated by angiography. In the 13 patients with medial scallop prolapse and the three patients with lateral scallop prolapse, a regurgitant jet originated from a bulged portion of the posterior leaflet and was directed toward the opposite left atrial cavity to the bulged portion by short-axis images of color Doppler echocardiography.(ABSTRACT TRUNCATED AT 250 WORDS)

Value of transesophageal color Doppler echocardiography in the evaluation of coronary artery anatomy and blood flow

The purpose of this study was to test the efficacy of newly developed biplane transesophageal color Doppler and two-dimensional echocardiography in the evaluation of coronary artery anatomy and blood flow. Using these two techniques, high quality images of the entire main left coronary artery (from the left coronary ostium to the bifurcation of the left anterior descending and circumflex coronary arteries), adequate for assessment of luminal diameter and percent stenosis, were obtained in 34 (89%) out of 38 patients. Transesophageal color Doppler echocardiography visualized coronary blood flow in 32 (84%) of the 38 patients. Transesophageal two-dimensional echocardiography clearly showed significant (50% of greater) narrowing of the coronary lumen in 10 out of 12 patients (sensitivity; 83%) and insignificant narrowing or no abnormalities of the coronary lumen in 23 of 26 normal individuals (specificity; 88%). This preliminary study suggests that biplane transesophageal color Doppler and two-dimensional echocardiography are feasible, noninvasive techniques for imaging the main left coronary artery and blood flow.

Assessment of left-to-right atrial shunting after percutaneous mitral valvuloplasty by transesophageal color Doppler flow-mapping

To evaluate left-to-right shunts after percutaneous balloon mitral valvuloplasty, we studied 15 consecutive patients by using transesophageal color Doppler flow-imaging system. Transesophageal color Doppler examinations were performed five times in each patient (before valvuloplasty and 1 day, 1 week, 1 month, and 6 months after valvuloplasty). No shunt flow was observed before valvuloplasty. On 1 day after mitral valvuloplasty, transesophageal color Doppler echocardiography demonstrated left-to-right shunts in 13 (87%) of 15 patients. However, a significant oxygen step-up was present in the right heart in only one patient. The mean diameter of the interatrial septal defect detected by transesophageal two-dimensional echocardiography was 1.8 +/- 1.0 mm. The mean velocity of left-to-right shunting flow measured by high-pulse repetition frequency Doppler technique was 0.83 +/- 0.38 m/sec. One week after the procedure, left-to-right shunt flow was detected in 11 (73%) patients. One month after valvuloplasty, left-to-right shunting flow was detected in seven (47%) of 15 patients. There was a significant decrease in the diameter of an interatrial septal defect between 1 day and 1 week (p less than 0.01), between 1 week and 1 month (p less than 0.01), and between 1 month and 6 months (p less than 0.05). Six months after valvuloplasty, left-to-right shunting flow remained in three (20%) patients. By using transthoracic color Doppler echocardiography, we detected left-to-right shunting flow in two patients on 1 day after the procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Noninvasive diagnosis of coronary artery fistula by Doppler color flow mapping

Sixteen patients with coronary artery fistula proved by coronary angiography or surgery were studied using two-dimensional echocardiography and Doppler color flow mapping. The coronary artery fistula drained into the right atrium in 4 patients, the right ventricle in 2 and the pulmonary artery in 10. The dilated coronary artery was visualized in 7 of the 16 patients with a fistula, as compared with none of the 40 control subjects. These 7 patients included 5 of 6 patients with a fistula draining into the right atrium or right ventricle and only 2 of 10 patients with a fistula draining into the pulmonary artery. Abnormal flow signals in the dilated coronary artery were visualized with Doppler color flow mapping in five of these seven patients. Color flow imaging visualized abnormal flow signals with mosaic appearance in the pulmonary artery in eight patients, the right atrium in four and the right ventricle in two. The chamber in which abnormal signals were detected corresponded with the entry site of the fistula by angiography. Intraoperative imaging during surgical repair was needed in two cases to confirm ligation of all arteries feeding into the fistula network. In conclusion, Doppler color flow imaging is diagnostically useful to visualize shunt flows originating from the opening or exit of a coronary artery fistula. Furthermore, intraoperative use of this technique may provide confirmation of successful surgical ligation of the fistula.

Inhibitory activities and inhibition specificities of caffeic acid derivatives and related compounds toward 5-lipoxygenase

Various caffeic acid derivatives were synthesized, and their effects on 5-lipoxygenase (5-LO), 12-lipoxygenase (12-LO) and prostaglandin (PG) synthase activities were investigated. Among them, caffeic acid octyl amide (5) and 1-(3,4-dihydroxyphenyl)-1-octen-3-one (11) showed very potent inhibitory activities toward 5-LO with IC50 values of 4.2 x 10(-8) and 3.5 x 10(-8) M, respectively. They were very selective inhibitors for 5-LO. Compound 11 showed non-competitive inhibition, and the two adjacent hydroxy groups attached to the benzene ring, as well as the hydrophobic alkyl side chain, were required for its strong binding to 5-LO.

Temporal resolution of mitral regurgitation in patients with mitral valve prolapse: a phonocardiographic and Doppler echocardiographic study

To assess the timing and duration of mitral regurgitation in mitral valve prolapse, 20 patients with a mid-systolic click or late systolic murmur, or both (Group 1) and 16 patients with a pansystolic murmur with late systolic accentuation (Group 2) were studied with phonocardiography and echocardiography including various Doppler techniques. The subjects' ages ranged from 15 to 73 years. Mitral valve prolapse with mitral regurgitation was observed in 15 of 20 patients in Group 1 and in all 16 patients in Group 2. M-mode Doppler color echocardiography demonstrated a mitral regurgitant signal throughout systole and isovolumic relaxation in all but 1 of these 31 patients regardless of the pattern of the systolic murmur. The regurgitant signal was recorded after the click in only one patient with mitral valve prolapse in Group 1. Two of the five patients in Group 1 without two-dimensional echocardiographic findings of mitral valve prolapse had the early systolic signal of mitral regurgitation. The timing and duration of the mitral regurgitant signal detected in patients in Group 1 with pulsed or continuous wave Doppler ultrasound varied with the site of the sample volume or beam direction. In the patients in Group 2, however, the signal was demonstrated throughout systole and isovolumic relaxation by both Doppler methods. Compared with M-mode Doppler color echocardiography, therefore, pulsed and continuous wave Doppler methods were less sensitive and thus inadequate to investigate the timing and duration of mitral regurgitation in mitral valve prolapse, especially in patients with a mid-systolic click or a late systolic murmur, or both, who had mild or eccentric mitral regurgitant jets.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatotoxic action of a poisonous mushroom, Amanita abrupta in mice and its toxic component

An aqueous extract of a poisonous mushroom, Amanita abrupta was injected intraperitoneally into male ICR mice and the acute effects on the liver were studied. Contents of serum glucose and liver glycogen decreased to 60% and 10% of the control levels, respectively, 6 h after injection. Activities of serum glutamic oxaloacetic transaminase and serum glutamic pyruvic transaminase increased to 3- and 8-fold, respectively, 12 h after injection, and the elevated activities were maintained up to 24 h. Activities of the hepatic drug metabolizing enzymes were also reduced 15 h after injection. Histological examination demonstrated massive liver cell necrosis and disappearance of glycogen granules in the liver of the treated animals. Two amino acids, L-2-amino-4-pentynoic acid and L-2-amino-4,5-hexadienoic acid were identified in the mushroom extract. The former caused similar biochemical effects to those of the mushroom extract.

[A study of multiple primary cancers of the stomach and other organs]

The incidence of associated synchronous or heterochronous malignant tumors in this series was 3.3% (21/633). These patients were found more in multiple cancer than single cancer of the stomach. A relatively high incidence of associated cancer of other organs was found with cancer of the large bowel and of the cervix in heterochronous cancer and cancer of the esophagus in synchronous tumors. The cumulative corrected 10-year survival rate of 15 cases of heterochronous tumors was 85.7%. On the other hand, six patients with synchronous tumor had more advanced cancer of other organs than gastric cancer, and four of them died due to cancer of other organs within two years. Both primaries should be found at the early stage and treated with curative surgery and/or radiotherapy.

[Clinico-pathological study and surgical treatment of cancer of the greater curvature of the stomach]

We retrospectively studied the clinicopathological features and surgical treatment of patients with cancer of the great curvature seen between 1967--1977. The incidence of cancer of the greater curvature in gastrectomized patients was 11% (31/281): this was the least frequent of four locations. Curatively resected patients, the five-year survival rate of those with cancer of the greater curvature was 50%, significantly lower than in patients with cancer of the anterior and posterior wall. Factors influencing the survival rate were age, size of the tumor, stage of the cancer, the presence of poorly differentiated adenocarcinoma, and relative curative resection. To improve the results of surgical treatment, early diagnosis and extended lymph node dissection are essential.

Effects of surgical treatment and adjuvant chemotherapy studied by the depth of penetration in gastric cancer patients undergoing curative gastrectomy

This report concerns 133 of 377 patients with gastric cancer who underwent curative gastric resection at the First Department of Surgery, Shinshu University Hospital, between January 1, 1967, and December 31, 1975. The effects of surgical treatment and adjuvant chemotherapy were investigated for every depth of penetration into the gastric walls. The 5-year survival rate was 41.7% among patients subjected to gastrectomy and 61.7% among those treated by curative gastrectomy. The 5-year survival rate decreased along with increased depth of invasion. Following surgical treatment, the 5-year survival rate was higher in the patients who underwent absolute curative resection than in those who were subjected to relatively curative resection. Extended radical gastrectomy is needed for patients with the depth of invasion through the muscularis propria. It is necessary to complement chemotherapy for patients with lymph node metastasis who are subjected to relative curative gastrectomy. In the patients with serosal invasion, papillary and tubular adenocarcinoma decreased and poorly differentiated adenocarcinoma increased substantially. The patients with poorly differentiated adenocarcinoma had a poorer prognosis than did those with tubular adenocarcinoma. Some ideas for the treatment of poorly differentiated adenocarcinoma are earnestly hoped for.