[Surgical results of valvuloplasty for common atrioventricular valve regurgitation in single ventricle]

From 1988 through 1994, 18 patients who had common atrioventricular valve regurgitation associated with single ventricle underwent valvuloplasty. All patients had isomerism heart (right isomerism: 16, left isomerism: 2). The preoperative degree of regurgitation was 3.3 +/- 0.4 (Sellers). Valvuloplasty was performed by two different procedures. Semi-circular annuloplasty was used in nine patients. Dividing the common atrioventricular valve orifice into two parts (bivalvation) with or without annuloplasty was used in nine. The concomitant procedures varied: three patients underwent systemic pulmonary shunt, two underwent repair of total anomalous pulmonary venous drainage, one underwent pulmonary arterial banding, five underwent bidirectional Glenn, shunt, and four underwent Fontan operation. One early death and three late deaths have occurred. The early postoperative degree of regurgitation was reduced to 1.3 +/- 1.0. In nine patients, however, the degree of regurgitation increased late postoperatively. Seven patients were reoperated on because of regurgitation: three patients had valve replacement and four had reannuloplasty. Increased incidence of deterioration of regurgitation in late period was seen in patients under 2 years old and those receiving a concomitant Blalock shunt. Lower event-free rate after 2 years was seen in patients with double inlet right or indeterminate ventricle and those underwent the annuloplasty alone. We conclude that the dividing common atrioventricular valve orifice into two parts with annuloplasty could effectively reduce the regurgitation in most patients with isomerism heart, and the concomitant ventricular unloading operation seems to offer promise for improving long-term results.

Serine palmitoyltransferase is the primary target of a sphingosine-like immunosuppressant, ISP-1/myriocin

ISP-1/myriocin is a new type of remarkably potent immunosuppressant, the structure of which is homologous to sphingosine. ISP-1/myriocin inhibited the proliferation of an IL-2-dependent mouse cytotoxic T cell line, CTLL-2, at nanomole concentrations. ISP-1/myriocin inhibits serine palmitoyltransferase activity at picomole concentrations. This enzyme catalyzes the first step of sphingolipid biosynthesis and reduces the intracellular pool of sphingolipid intermediates. The growth inhibition induced by ISP-1/myriocin was completely abolished by the addition of sphingosines or sphingosine-1-phosphate, but not by sphingomyelin or glycosphingolipids. These results suggest that sphingosines or sphingosine-1-phosphate are associated with CTLL-2 proliferation, and ISP-1/myriocin suppresses T cell proliferation by the modulation of sphingolipid metabolism. ISP-1/myriocin should be a useful tool for the study of the sphingolipid pathway, which has been associated with various kinds of signal transduction.

[Postoperative pulmonary stenosis after arterial switch operation, comparison in three methods of pulmonary reconstruction: modified Pacifico, autologous pericardial patch, and equine pericardial patch]

To prevent postoperative pulmonary stenosis in arterial switch operation for transposition of the great arteries, pulmonary reconstruction without patch augmentation (modified Pacifico method: Pa-group) and reconstruction using W-shaped fresh autologous pericardium (AW-group) were introduced instead of the former method using equine pericardium (XW-group). Postoperative pulmonary stenosis (RV-PA pressure gradient greater than 30 mmHg) was not seen among the 17 cases in the Pa-group (0%), and was seen in 2/14 (14.3%) in the AW-group and in 4/14 (29%) in the XW-group. Progressive increase in pressure gradient was seen in the XW-group in the midterm cardiac catheterization (p < 0.01), but such tendency was not observed in the Pa-group and the AW-group. Sectional area at the pulmonary valve ring, at the anastomotic site in the main pulmonary artery, and at the pulmonary branches just distal to the bifurcation, standardized by the body surface area, increased in the Pa-group and the AW-group, but were unchanged or slightly decreased in the XW-group in the midterm cardiac angiography. We believe that postoperative pulmonary stenosis can be best avoided if modified Pacifico method is used. The cases in which postoperative pulmonary stenosis or coronary artery compression is anticipated such as those with side-by-side aortopulmonary relationship or after pulmonary artery banding, should be operated upon using fresh autologous pericardial patch.

Rapid corepressor exchange from the trp-repressor/operator complex: an NMR study of [ul-13C/15N]-L-tryptophan

[ul-13C/15N]-L-tryptophan was prepared biosynthetically and its dynamic properties and intermolecular interaction with a complex of Escherichia coli trp-repressor and a 20 base-pair operator DNA were studied by heteronuclear isotope-edited NMR experiments. The resonances of the free and bound corepressor (L-Trp) were unambiguously identified from gradient-enhanced 15N-1H HSQC, 13C-1H HSQC, 13C- and 15N-edited 2D NOESY spectra. The exchange off-rate of the corepressor between the bound and free states was determined to be 3.4 +/- 0.52 s-1 at 45 degrees C, almost three orders of magnitude faster than the dissociation of the protein-DNA complex. Examination of the experimental NOE buildup curves indicates that it may be desirable to use longer mixing times than would normally be used for a large molecule, in order to detect weak intermolecular NOEs in the presence of exchange. Intermolecular NOEs from bound corepressor to trp-repressor and DNA were analyzed with respect to the mechanism of ligand exchange. This analysis suggests that, in order for the ligand to diffuse out of the complex, there must be significant movement or 'breathing' of the protein and/or DNA.

Coxa magna after open reduction for developmental dislocation of the hip

We studied coxa magna after open reduction of developmental hip dislocation, including the etiology, incidence, and influence on the long-term results and acetabular development. Forty-seven hips in 47 patients were radiographically examined for at least 10 years, and another 20 hips in 20 patients were examined arthrographically at an early stage after open reduction. At follow-up, the incidence of coxa magna, which was defined as a femoral head with a size > or = 20% greater than the opposite side, was 34.0%, and that seemed to be one of factors that worsened the long-term results. One of the most important causes of coxa magna is to overwiden the acetabular capacity by excising the limbus; another cause is the surgical invasion and synovitis of the hip joint after operation.

Enzyme immunoassay of immunoreactive progastrin-releasing peptide(31-98) as tumor marker for small-cell lung carcinoma: development and evaluation

Previously, using recombinant human progastrin-releasing peptide (ProGRP)(31-98), we developed a RIA for ProGRP(31-98) and demonstrated that the determination of serum ProGRP(31-98) was a reliable marker for small-cell lung carcinoma (SCLC) (Miyake et al., Cancer Res 1994;54:2136-40). Aiming for a more convenient assay system, we have now developed and evaluated a highly sensitive and specific ELISA for ProGRP(31-98). Only 50 microL of nonextracted serum is needed, and results are obtained in only 2 h. Intraassay and between-day CVs were 1.7-4.6% and 4.2-6.8%, respectively. The log-log calibration curve was linear to 1000 ng/L, and analytical recovery was 91.5-108.7%. The detection limit of this assay, 1.9 ng/L, means that basal concentrations of ProGRP(31-98) were detectable in all healthy subjects. The cutoff value, based on the mean + 3 SD of concentrations in 247 healthy subjects, was set to 45.1 ng/L. Serum concentrations exceeded this value in 18 of 25 SCLC patients, similar to the frequency of increased values found by RIA previously. In contrast, the frequency of increased serum ProGRP(31-98) in patients with nonmalignant pulmonary diseases or non-SCLC was quite low: 0% and 5.0%, respectively. Such results may justify a clinical trial for evaluating this ELISA for the diagnosis and monitoring of SCLC patients.

Microbiological features of gingivitis in pubertal children

The subgingival microflora of 42 pubertal children (aged 12-15 years) and 18 young adults (aged 21-25 years) was investigated by anaerobic culture and phase contrast microscopy. Motile rods, spirochetes and Prevotella intermedia were elevated proportionately in pubertal children with gingivitis (median GI > or = 1); however, no statistically significant differences in enumerated organisms on selective media were observed between pubertal children and young adults. These organisms were positively correlated with the index of bleeding on probing and the gingival index of pubertal children. Pubertal children were divided into 3 distinct subject clusters according to the similarity of subgingival microbial features, and the subjects who were then selected for the gingivitis group were distributed into clusters 1 and 2. The proportions of motile rods, P. intermedia and Eikenella corrodens were significantly higher in cluster 2 than in cluster 1. These results suggest that these 2 species and motile rods which differentiated features of clusters, are useful for screening of high-risk subjects for worsening of inflammation.

Enzyme immunoassay of immunoreactive progastrin-releasing peptide(31-98) as tumor marker for small-cell lung carcinoma: development and evaluation

Previously, using recombinant human progastrin-releasing peptide (ProGRP)(31-98), we developed a RIA for ProGRP(31-98) and demonstrated that the determination of serum ProGRP(31-98) was a reliable marker for small-cell lung carcinoma (SCLC) (Miyake et al., Cancer Res 1994;54:2136-40). Aiming for a more convenient assay system, we have now developed and evaluated a highly sensitive and specific ELISA for ProGRP(31-98). Only 50 microL of nonextracted serum is needed, and results are obtained in only 2 h. Intraassay and between-day CVs were 1.7-4.6% and 4.2-6.8%, respectively. The log-log calibration curve was linear to 1000 ng/L, and analytical recovery was 91.5-108.7%. The detection limit of this assay, 1.9 ng/L, means that basal concentrations of ProGRP(31-98) were detectable in all healthy subjects. The cutoff value, based on the mean + 3 SD of concentrations in 247 healthy subjects, was set to 45.1 ng/L. Serum concentrations exceeded this value in 18 of 25 SCLC patients, similar to the frequency of increased values found by RIA previously. In contrast, the frequency of increased serum ProGRP(31-98) in patients with nonmalignant pulmonary diseases or non-SCLC was quite low: 0% and 5.0%, respectively. Such results may justify a clinical trial for evaluating this ELISA for the diagnosis and monitoring of SCLC patients.

Identification of endo-beta-N-acetylglucosaminidase and N-acetylmuramyl-L-alanine amidase as cluster-dispersing enzymes in Staphylococcus aureus

Two proteins which are capable of dispersing cell clusters of Staphylococcus aureus have been purified from a S. aureus FDA209P culture supernatant. Both of them were found to have bacteriolytic activity. From the elution profile of column chromatography and Western blot (immunoblot) analysis, one of them was identified as a 51-kDa endo-beta-N-acetylglucosaminidase (GL). The other was a 62-kDa protein on the basis of sodium dodecyl sulfate gel electrophoresis. Analysis of the peptidoglycan fragments following treatment with the 62-kDa protein indicated that this protein is an N-acetylmuramyl-L-alanine amidase (AM). In vitro studies of cluster dispersion activities using S. aureus mutant strains Lyt66 or S. aureus Wood46 grown as clusters demonstrated that these two enzymes act synergistically to disperse clusters into single cells. Antiserum against the 51-kDa GL cross-reacted with the 62-kDa AM, and S. aureus FDA209P grown in the presence of anti-51-kDa-GL immunoglobulin G induced giant clusters. Clusters induced by anti-51-kDa GL and by Cibacron blue F3G-A were dispersed by coincubation with the 51-kDa GL and the 62-kDa AM. Western blot analysis demonstrated that the 51-kDa GL and the 62-kDa AM were missing in culture supernatants of S. aureus Lyt66, Wood46, and RUSAL2 (Tn551 autolysin-defective mutant), which grow in clusters. These results strongly suggest that the 51-kDa GL and 62-kDa AM are involved in cell separation of daughter cells after cell division.

[Foveal cone densitometer and changes in foveal cone pigments with aging]

A foveal cone densitometer was built for measuring the kinetics of foveal cone pigments in human eyes. The light from a 500-W xenon lamp was divided into reference, measuring, and bleaching beams, and projected through an optical fiber leading to a modified fundus camera. After the light was projected into the ocular fundus, the reflected light (central 1 degree) was measured by a photomultiplier and the regeneration time and the two-way density were abstracted from the records. The two-way density, which is the decadic logarithm of the measuring-reference beam ratio under bleached conditions divided by the measuring-reference beam ratio under dark conditions, eliminated the artifacts caused by eye movement of blink. Reliable curves were obtained in 45 eyes out of 53 healthy Japanese subjects (age range, 9 to 82 years). The mean +/- standard deviation SD of the two-way density (log) and the time constant (sec) were 0.34 +/- 0.09 and 139.9 +/- 79.3, respectively. The time constant significantly increased with aging.

A new method for distortion correction of electronic endoscope images

A new method to correct the barrel distortion of an electronic endoscope image is presented. A correction model assuming circularly symmetric distortion is introduced with the following model parameters: the center of distortion and the coefficients of polynomials representing the distortion correction in the radial direction. If the imaging system is distortion-free, straight lines in the object space should be imaged as straight lines. Based on this criterion, a distorted image of a standard pattern consisting of a grid of several straight lines is recorded, and the model parameters are then estimated as a basis for straightening distorted lines. This method has the advantage of not needing a careful placement of the standard pattern for calibration. Correction results are presented for the grid pattern chart to verify a sufficient degree of correction. Examples of distortion correction of real intestinal images and physicians' comments are also presented.

Effects of lansoprazole on gastric ulcer healing and mucin content

The effect of lansoprazole, a new benzimidazole proton pump inhibitor, on the relationship between ulcer healing and changes in mucin content was studied in gastric ulcer patients. Twenty-one outpatients with active gastric ulcers received lansoprazole 30 mg once daily given in the morning for 8 weeks. The gastric mucin content was examined by HPLC analysis of hexosamines in gastric biopsy specimens obtained from the lesser curvature of the pylorus and the greater curvature of the upper body. The ulcer healing rate for lansoprazole was 85.7% at 8 weeks. The mucin content of both mucosal regions significantly decreased to approximately 70% (pylorus 70.9%; upper body 74.7%) of the value before drug treatment. The results of this study demonstrate that 30 mg lansoprazole once daily is remarkably effective in healing gastric ulcers because of its potent acid suppression. It appears that acid inhibition is the primary factor in initial treatment. However, maintaining an altered gastric mucosal defense mechanism may have implications for the long-term treatment of gastric ulcers.

The effect of Triton X-100 on the in-vitro susceptibility of methicillin-resistant Staphylococcus aureus to oxacillin

The effect of the non-ionic detergent, Triton X-100, on the in-vitro activity of oxacillin against methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) strains of Staphylococcus aureus was investigated. In the presence of Triton X-100, the MICs of oxacillin for both MRSA and MSSA isolates were reduced; this enhancing effect was particularly marked for the MRSA strains. Triton X-100 therefore counteracted the resistance to methicillin encoded by mecA. In the presence of oxacillin at subinhibitory concentrations, Triton X-100 induced the bacteriolysis of MRSA and potentiated the autolysis of these organisms. However, the detergent had no effect on the bacteriolytic enzyme profile or the susceptibility of the bacterial cell wall to bacteriolytic enzymes, nor did it promote the binding of oxacillin to the penicillin-binding protein (PBP) 2A. On the other hand, it stimulated the release from the bacteria of acylated lipoteichoic acid (LTA), a putative endogenous regulator of autolysins. Autolytic enzyme-deficient MRSA mutants were equally as sensitive as the parent strain to the effect of Triton X-100 on susceptibility to oxacillin. These results indicate that the enhanced in-vitro activity of oxacillin against MRSA in the presence of Triton X-100 cannot be accounted for simply by the induction of bacteriolysis following activation of autolytic enzymes by the detergent-stimulated release of LTA.

Isolation and characterization of Staphylococcus aureus mutants which form altered cell clusters

Staphylococcus aureus FDA 209P produces two extracellular bacteriolytic enzymes, 51-kDa endo-beta-N-acetylglucosaminidase (GL) and 62-kDa N-acetylmuramyl-L-alanine amidase (AM), both of which can disperse cell clusters. To characterize the physiological roles of these enzymes in vivo, mutants with altered autolysin activity were isolated, and their degree of cluster formation in broth culture was assessed. Bacteriolytic activities of GL and AM, produced and secreted from these mutants into the culture fluid and detected with activity gels, coincided well with the degree of cluster formation of the mutants. The mutants with little or no enzyme activity grew in clusters, whereas those with high activity grew as well-separated cocci, suggesting that these enzymes are involved in cell separation of S. aureus in vivo.

Relationship between intracellular period modulation and external environment change in Physarum plasmodium

The relationship between intracellular period modulation and external environment change was investigated from the viewpoint of internal information coding in Physarum plasmodium. For the external conditions, concentration changes of attractant (galactose) and repellent (KCl) were used, and the internal responses were measured as the thickness oscillation of the plasmodium. (i) Period of the intracellular oscillation decreased when the concentration of attractant was increased and when the concentration of repellent was decreased. (ii) The period increased when the attractant was decreased and when the repellent was increased. (iii) The larger concentration change induced the larger period modulation. (iv) These responses were observed when the change of concentration was greater than a threshold value. From these results, it was clarified that the relative change in environmental condition is encoded on the relative period modulation in intracellular oscillation. This means that the period change does not directly represent the environment itself but represents the change of its condition. Thus, it is further suggested that the plasmodium estimates the environmental condition based on the relationship between the previous external condition and the present one.

[Analysis of electrically evoked response in relation to the central pathway of the cat (3). Current source density analysis in area 17 of cats]

We analyzed current source density and multiple unit activity of area 17 of cats in response to transcorneal electrical stimuli to clarify the localization of the transmembrane current flows contributing to the generation of the electrically evoked response. The results of the current source density analysis were as follows. 1. Current sinks within 20 ms were observed in layers 4 and 6. 2. Current sinks corresponding to N3 (latency 35 ms) were detected in layers 4 and lower 3 and current sources were in the supragranular layers. 3. Current sinks with a latency of more than 40 ms were observed in the supragranular layers. Simultaneous multiple unit activity was present in cases 1 and 2. With increased stimulus frequency or double electrical stimuli, the current sinks corresponding to N3 were decreased. These findings indicate that N1 (latency 9 ms) and N2 (latency 20 ms) reflect near-field potentials generated by geniculocortical afferents in layers 4 and 6, and that N3 is a post-and polysynaptic component. In addition, it appears that dipoles consisting of cell bodies and apical dendrites of pyramidal cells in layer 3 generated by satellite cell in layer 4, play a major role in generating N3.

Scotopic threshold response in complete and incomplete types of congenital stationary night blindness

PURPOSE

To study the function of the rod visual pathway in the complete and incomplete types of congenital stationary night blindness (CSNB), with special reference to the scotopic threshold response (STR) of electroretinograms (ERGs)

METHODS

Using full-field stimuli with light intensities ranging from near absolute threshold to bright, ERG intensity series from two patients with complete CSNB, four patients with incomplete CSNB, and four normal subjects were recorded.

RESULTS

Neither the rod b-wave nor the STR was recordable from the patients with complete CSNB. In the patients with incomplete CSNB, the STR was clearly recorded, although the absolute threshold was elevated in accordance with elevation of the psychophysical absolute threshold. The b-wave stimulus threshold was not elevated, and the b-wave amplitude near the threshold was normal. The peak time of the STR was delayed by approximately 80 msec, whereas that of the b-wave was normal.

CONCLUSIONS

These STR results indicate that the rod system abnormality in complete CSNB differs from that in incomplete CSNB. Furthermore, the greatly delayed peak time of STR in the patients with incomplete CSNB made the interaction between b-wave and STR different from that in normal subjects.

Comparison of American and Japanese outpatients with borderline personality disorder

The borderline psychopathology of 33 American and 19 Japanese female outpatients who met the Revised Diagnostic Interview for Borderlines (DIB-R) criteria for borderline personality disorder (BPD) was compared. There were significant differences between the samples in the DIB-R total score, as well as in the affect/cognition section and scaled section scores. However, only one of the 22 summary statements (SS) of the DIB-R distinguished American borderlines from Japanese borderlines. Most of the differences seemed to reflect differences in inclusion criteria. It is concluded that there are borderline patients in Japan whose psychopathology is basically identical to that of American borderline patients.

Fundus albipunctatus-like lesions in juvenile retinoschisis

Images

[The focal macular electroretinogram in idiopathic macular hole]

Focal macular electroretinograms (MERGs) were recorded with three different sizes of stimulus spots, 5 degrees, 10 degrees, and 15 degrees in diameter, in 14 patients with unilateral idiopathic macular hole. Their fellow eyes were normal in terms of visual acuity (> 1.0), MERG, and ophthalmoscopic macular findings. The amplitudes and implicit times of the a-wave, b-wave, and oscillatory potentials (OP) were compared between affected and fellow eyes. The amplitudes of the a-wave, b-wave and OP in the affected eyes were significantly smaller (p < 0.01) in all spot sizes. The rate of amplitude reduction of OP was significantly smaller than that of the a-wave and b-wave in the spots of 10 degrees and 15 degrees (p < 0.05). With the stimulus sizes to evoke the a-waves and b-waves of similar amplitudes between the affected and fellow eyes, OP always had a much larger amplitude in the affected eye. This result confirms our previous finding that the distribution of OP is relatively sparse in the fovea, becoming more dense than the a-waves and b-waves away from the fovea toward the parafovea and perifovea. The implicit time of the b-wave in the affected eyes was delayed significantly only in the 5 degrees spot (p < 0.01). The delay of the implicit time may result from the ring-shaped retinal detachment which always occurs in idiopathic macular hole.