Controlling joint instability after anterior cruciate ligament transection inhibits transforming growth factor-beta-mediated osteophyte formation

OBJECTIVE

Abnormal joint instability contributes to cartilage damage and osteophyte formation. We investigated whether controlling joint instability inhibited chronic synovial membrane inflammation and delayed osteophyte formation and examined the role of transforming growth factor-beta (TGF-β) signaling in the associated mechanism.

DESIGN

Rats (n = 94) underwent anterior cruciate ligament (ACL) transection. Anterior tibial instability was either controlled (CAM group) or allowed to continue (SHAM group). At 2, 4, and 8 weeks after surgery, radiologic, histopathologic, immunohistochemical, immunofluorescent, and enzyme-linked immunosorbent assay examinations were performed to evaluate osteophyte formation and TGF-β signaling.

RESULTS

Joint instability increased cartilage degeneration score and osteophyte formation, and cell hyperplasia and proliferation and synovial thickening were observed in the synovial membrane. Major findings were increased TGF-β expression and Smad2/3 following TGF-β phosphorylation in synovial membarene, articular cartilage, and the posterior tibial growth plate (TGF-β expression using ELISA: 4 weeks; P = 0.009, 95% CI [260.1-1340.0]) (p-Smad2/3 expression density: 4 weeks; P = 0.024, 95% CI [1.67-18.27], 8 weeks; P = 0.034, 95% CI [1.25-25.34]). However, bone morphogenetic protein (BMP)-2 and Smad1/5/8 levels were not difference between the SHAM model and the CAM model.

CONCLUSIONS

This study showed that the difference between anterior tibial instability caused a change in the expression level of TGF in the posterior tibia and synovial membrane, and the reaction might be consequently involved in osteophyte formation.

Arrhythmia Curve Interpretation Using a Dynamic System Model of the Myocardial Pacemaker

A problem of identifying the phase response curve of the myocardial pacemaker was investigated using a simple dynamic system model of cardiac arrhythmia. A hybrid optimization method of a genetic algorithm and a local optimization technique was employed to obtain a solution of the model fitting. The method was applied to two categories of arrhythmias, ventricular parasystole and high-degree AV block. The present study offered a new insight into the mechanism of cardiac arrhythmias.

Controlling joint instability delays the degeneration of articular cartilage in a rat model

OBJECTIVE

Joint instability induced by anterior cruciate ligament (ACL) transection is commonly considered as a predisposing factor for osteoarthritis (OA) of the knee; however, the influence of re-stabilization on the protection of articular cartilage is unclear. The aim of this study was to evaluate the effect of joint re-stabilization on articular cartilage using an instability and re-stabilization ACL transection model.

DESIGN

To induce different models of joint instability, our laboratory created a controlled abnormal joint movement (CAJM) group and an anterior cruciate ligament transection group (ACL-T). Seventy-five Wistar male rats were randomly assigned to the CAJM (n = 30), ACL-T (n = 30), or no treatment (INTACT) group (n = 15). Cartilage changes were assessed with soft X-ray analysis, histological and immunohistochemistry analysis, and real-time polymerase chain reaction (PCR) analysis at 2, 4, and 12 weeks.

RESULTS

Joint instability, as indicated by the difference in anterior displacement between the CAJM and ACL-T groups (P < 0.001), and cartilage degeneration, as evaluated according to the Osteoarthritis Research Society International (OARSI) score, were significantly higher in the ACL-T group than the CAJM group at 12 weeks (P < 0.001). Moreover, joint re-stabilization maintained cartilage structure (thickness [P < 0.001], surface roughness [P < 0.001], and glycosaminoglycan stainability [P < 0.001]) and suppressed tumor necrosis factor-alpha (TNF-α) and caspase-3 at 4 weeks after surgery.

CONCLUSION

Re-stabilization of joint instability may suppress inflammatory cytokines, thereby delaying the progression of OA. Joint instability is a substantial contributor to cartilage degeneration.

Chiral magnetic soliton lattice on a chiral helimagnet

Using Lorenz microscopy and small-angle electron diffraction, we directly present that the chiral magnetic soliton lattice (CSL) continuously evolves from a chiral helimagnetic structure in small magnetic fields in Cr(1/3)NbS2. An incommensurate CSL undergoes a phase transition to a commensurate ferromagnetic state at the critical field strength. The period of a CSL, which exerts an effective potential for itinerant spins, is tuned by simply changing the field strength. Chiral magnetic orders observed do not exhibit any structural dislocation, indicating their high stability and robustness in Cr(1/3)NbS2.

Effect of position of electrodes relative to the innervation zone onsurface EMG

We investigated the effect of the position of electrodes relative to the innervation zone (IZ) of the biceps brachii muscle during isometric elbow flexion using eight-channel surface array electrodes. We estimated the location of the IZ near the centre of the muscle in 20 male subjects. The pulse peaks from electromyogram (EMG) waveforms were detected for each channel and averaged, the triphasic pulse was determined, and the peak values of the first and third phases were compared. The results showed significantly greater pulse values for the first phase when the electrode placement was proximal to the estimated IZ, and for the third phase when the electrode placement was distal to the estimated IZ. Using this method, the positional relationship between electrodes and IZ can be determined using a surface EMG waveform recorded with a pair of bipolar electrodes. This method may be clinically useful in confirming the reliability of a recorded surface EMG.

A Seroepidemiological Study of HTLV-1 Infection in Nepal

A seroepidemiological survey of antibodies to human T-lymphotropic retrovirus type-1 (HTLV-1) was carried out among 413 residents of Chitwan, Dhapakhel and Katmandu in Nepal. Donor screening was first carried out by the gelatin particle agglutination (PA) tests and positive sera were retested by an improved PA test, indirect immunofluorescence (IF) and Western blotting (WB). Nine sera showed positive reaction in the first PA screening. Among these positive sera, 1 serum was positive in the improved PA test and the IF test but negative in the WB test. This study suggests that the prevalence of HTLV-1 in Nepalese people is negligible.

Contrasting alteration patterns of different cartilage plates in knee articular cartilage after spinal cord injury in rats

STUDY DESIGN

Experimental, controlled trial, animal study.

OBJECTIVE

To assess morphologic changes in different cartilage plates after spinal cord injury and identify the localization of these alterations.

SETTING

Saitama, Japan.

METHODS

A total of 16 Wistar rats were used. Eight rats underwent a spinal cord injury and eight rats had no intervention as control. The cartilage alterations of the knee joint were evaluated with radiography and histomorphometric analysis. To quantify cartilage alterations, we selected the histologic characteristics: thickness of the articular cartilage, number of chondrocytes, matrix staining to toluidine blue as a reflection of proteoglycan content and surface irregularity.

RESULTS

No differences in knee joints were found between the groups by radiography. In the medial knee joint, cartilage thickness of spinal-cord-injured knees increased at the anterior femoral region and decreased at the tibial and posterior femoral regions; however, in the lateral knee, that of spinal cord injuries did not change compared with control knees. Spinal cord injuries decreased the number of chondrocytes, especially at the anterior femoral regions. Matrix staining increased partially at the tibial regions. Surface irregularity of spinal-cord-injured knees was comparable to that of control knees in all cartilage plates.

CONCLUSION

The present findings exhibit characteristics of the cartilage after spinal cord injury. These alterations were different in nature between the medial and lateral regions. Future studies should assess separately different cartilage plates, to overestimate these severities when the changes at the medial knee were examined and to underestimate when the changes at the lateral knee were examined.

Alteration in articular cartilage of rat knee joints after spinal cord injury

OBJECTIVE

Mechanical forces are crucial for the maintenance of the morphologic and functional integrity of articular cartilage. The alteration of the articular cartilage after spinal cord injury (SCI) has been described in relation to a suppression of mechanical forces, since the joint is unloaded and restricted in movement. However, the morphological and biochemical characteristics of the cartilage after SCI are still poorly understood. We identified the localization of cartilage alterations after SCI and verified the influence of mechanical forces on the articular cartilage.

METHOD

A total of 32 Wistar rats were used. Sixteen animals underwent an SCI and 16 animals served as control. The articular cartilage of the knee joint was assessed, respectively, at 4, 8, 10, and 12 weeks after intervention by histochemical, histomorphometric, immunohistochemical, and biochemical analyses.

RESULTS

Cartilage thickness of spinal cord-injured knees decreased at the tibial and posterior femoral (FP) regions and increased at the anterior femoral (FA) region. Spinal cord injuries decreased the number of chondrocytes at the anterior regions and decreased the cartilage matrix staining only at the tibial regions. Immunolabeling to collagen type II was noted comparably in the superficial layer but noted weakly from the middle to deep layer. Collagen type I existed excessively at the cartilage surface and the pericellular regions.

CONCLUSION

Cartilage alterations after SCI would not be explained by only a suppression of mechanical forces by unloading and immobilization, but there may be influences on the cartilage in addition to the change in mechanical forces.

Allele frequencies of the six miniSTR loci in a population from Japan

Allele frequencies and forensic parameters for the six miniSTR loci D1S1677, D2S441, D4S2364, D10S1248, D14S1434, and D22S1045 were investigated in a sample of 142 unrelated healthy Japanese individuals. The polymerase chain reaction (PCR) products contained within the six loci were less than 119 bp in size. The frequency distributions in the six short tandem repeat (STR) loci showed no deviations from Hardy-Weinberg equilibrium expectations. The accumulated powers of discrimination and power of exclusion for the six loci were 0.999998 and 0.98, respectively. It was thus considered that due to the small PCR products and the moderate degree of polymorphism, analysis with use of the six miniSTR loci was highly beneficial for the forensic analysis of degraded DNA.

Remnant-like lipoprotein particles as risk factors for coronary artery disease in elderly patients

Although remnant-like lipoprotein particles (RLPs) are known to be atherogenic, the relationship between serum RLP-cholesterol (RLP-C) level and coronary artery disease (CAD) has not as yet been evaluated. This clinical study was aimed at investigating the pathological significance of serum RLP-C among several coronary risk factors with a clear focus on elderly patients. We took fasting venous blood samples to determine lipid profiles including RLP-C from 188 patients with angiographically identified CAD and 68 control patients. Overall analysis showed that the RLP-C/HDL-C ratio was higher in both single-vessel CAD group (n = 67; p < 0.01) and multi-vessel CAD group (n = 121; p < 0.001) compared to controls. Further, multiple logistic regression analysis indicated that the diabetes, HDL-C and the RLP-C/HDL-C ratio could discriminate CAD patients from controls. In patients younger than 65 years, diabetes, HDL-C, LDL-C and the LDL-C/HDL-C ratio as well as the RLP-C/HDL-C ratio could discriminate CAD. In patients 65 aged years or older, however, diabetes, triglyceride and RLP-C as well as the RLP-C/HDL-C ratio could discriminate CAD, whereas LDL-C and the LDL-C/HDL-C ratio could not. These results led us to believe that the contribution of a given risk factor to the development of CAD in elderly patients may be different from that in younger patients. In elderly patients, RLP-C rather than LDL-C was strongly associated with the development of CAD. Accordingly, serum RLP-C levels may serve as a convenient and reliable index for assessing CAD.

Acute myocardial infarction associated with myocardial bridge and coronary artery vasospasm

A 65-year-old man was admitted to our hospital with acute myocardial infarction (MI). Emergency coronary angiography showed no significant organic lesions, but a myocardial bridge was found at the mid-left anterior descending artery An acetylcholine provocation test revealed 90% spastic stenosis just proximal to the myocardial bridge. His acute MI could have been caused by both a coronary spasm and the myocardial bridge.

Molecular genetic analysis of the Am phenotype of the ABO blood group system

BACKGROUND AND OBJECTIVES

Many sequences of variants in the ABO blood group system have been analysed, but genetic information is not available on the rare Am phenotype blood group. We isolated the Am phenotype in one family and performed molecular analysis on this allele.

MATERIALS AND METHODS

Exons 6 and 7 of the ABO gene were analysed using genomic DNAs from members of one family containing Am phenotype individuals via polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing.

RESULTS

In the Am allele, two single base substitutions were detected compared with the A101 allele. Both were C --> T mutations at nucleotide positions 467 and 761. PCR-RFLP using the AccI restriction enzyme was performed to detect the Am allele in 214 samples that had already been determined as type A or O by serological tests, but no sample was found to contain an Am allele.

CONCLUSIONS

In this study a new allele with a single-base substitution at nucleotide position 761 was identified in the Am phenotype. We designated this new allele as A112 (according to the guidelines for human gene nomenclature) and determined that PCR-RFLP analysis using the AccI restriction enzyme will be useful for detecting this allele.

Cardiac pacing as emergency care for serious bradyarrhythmia with circulatory shock

Three cases of bradyarrhythmia with serious illness of extracardiac organs are reported. Case 1 had sick sinus syndrome. He was admitted to our hospital complaining of syncope and developed apnea. Case 2 had complete atrioventricular block and serious hepatic failure in the hospital. Case 3 had paroxysmal atrioventricular block. He complained of syncope which followed convulsions. Their symptoms might be due to circulatory shock caused by a lazy lower pacemaker from the ventricle. Emergent temporary pacing successfully improved the extracardiac organ dysfunction. Although their bradyarrhythmias were transient, permanent pacemakers were implanted to inhibit the recurrence. A quick temporary pacing should be indicated in patients with critical bradyarrhythmia like our cases for survival.

Rapid cardiac adaptation to exercise demand signal and execution of maximal leg muscle contraction

We investigated the neural regulation of the cardiac interval to an exercise demand signal and to a repeated exercise in 20 healthy human subjects. Electrocardiogram (ECG), muscle torque, and electromyogram (EMG) were simultaneously measured and their time relationships compared before and during the exercise. The R-R interval of ECG was directly increased by the exercise demand signal itself before the onset of EMG but not reflexly by muscle contraction. The cardiac interval decreased at the onset of exercise. Under the condition of repeated maximum eccentric training, the resting cardiac interval decreased prior to the exercise, whereas the brief increase in cardiac interval to the exercise demand signal remained unchanged. These results suggested that when autonomic nerve activity to the pacemaker is activated by the exercise demand signal, an initial effect of vagal nerve activity appears, and an effect of vagal nerve withdrawal and/or sympathetic nerve activity then appears. The responses of the heart and leg skeletal muscle at the onset of exercise are not synchronized, and the cardiac interval is controlled by vagal and sympathetic nerve activities to effect a transition to a high heart rate as quickly and smoothly as possible.

Significance of platelet aggregability immediately after blood sampling and effect of cigarette smoking

A novel type platelet aggregometer, a WBA Analyzer, has enabled us to obtain the platelet aggregability data immediately after blood sampling, which is considered to closely reflect in vivo platelet function. Using this analyzer, we measured the platelet aggregatory threshold index (PATI) 5 min after blood sampling and compared it with that 60 min after blood sampling in 20 healthy male volunteers (10 smokers and 10 non-smokers). In the non-smokers, PATI was 10.3+/-2.3 microM 5 min after blood sampling, and it decreased to 4.7+/-1.5 (P<0.001) 60 min after blood sampling. In the smokers, the PATI was 7.7+/-2.9 microM 5 min after blood sampling, and it decreased to 3.8+/-1.5 (P<0.001) at 60 min after blood sampling. In the smokers, the PATI 5 min after blood sampling increased after a 4-week cessation of smoking (10.4+/-2.9, P<0.01), although the PATI 60 min after blood sampling did not change (4.2+/-1.6 microM). The measurement of platelet aggregability immediately after blood sampling using a WBA Analyser may be useful to evaluate not only platelet function in various thrombotic disorders, but also the effects of various anti-platelet drugs. Cessation of smoking should also be encouraged in the light of the adverse effects on platelet function.

Using cineradiography for continuous dynamic-motion analysis of the lumbar spine

STUDY DESIGN

Cineradiography was used to analyze continuous dynamic motion in the lumbar spine.

OBJECTIVES

To identify motion patterns of the lumbar spine in asymptomatic volunteers and symptomatic patients with L4 degenerative spondylolisthesis, and to use the findings to discuss segmental instability in this disorder.

SUMMARY OF BACKGROUND DATA

The use of radiographic findings to assess lumbar spine instability remains controversial. Although some studies have reported on lumbar kinematics during actual movement, the motion patterns in asymptomatic volunteers and symptomatic patients with L4 degenerative spondylolisthesis have not been fully clarified.

METHODS

While asymptomatic volunteers (n=20; mean age, 27; control group) and symptomatic patients with L4 degenerative spondylolisthesis (n=41; mean age, 63; degenerative spondylolisthesis [DS] group) flexed from a sitting neutral position and back to the neutral position (flexion course), cineradiography was used to record lateral segmental lumbar motions. Twelve frames were selected during the flexion course, and flexion-extension angle (f-e angle) and translation in the sagittal plane were measured at each motion segment (L2-L3, L3-L4, L4-L5, and L5-S1). The DS group was classified into 2 subgroups according to percentage of slip: DS group I, with a slip equal to or less than 15%; and DS group II, with a slip of more than 15%. The motion pattern was compared between the groups.

RESULTS

In the control group, f-e angle and translation at the L2-L3, L3-L4, and L4-L5 segments moved simultaneously, although the L5-S1 segment showed an initial delay. The amount of f-e angle and translation changed almost symmetrically. In both f-e angle and translation, the L4-L5 segment showed a large motion pattern. In DS group I (n=21), the L4-L5 segment showed a large motion pattern in f-e angle and an intermediate motion pattern in translation. In DS group II (n=20), the L4-L5 segment showed an intermediate motion pattern in f-e angle, and a small motion pattern in translation. The relative range of f-e angle at the L4-L5 segment had the largest range in DS group I, and the relative translation showed a serial decrease from the control group through DS group II. A significant correlation between f-e angle and translation (harmonious motion pattern) was noted at the L2-L3, L3-L4, and L4-L5 segments in the control group. The harmonious motion pattern at the L4-L5 segment was significantly less in the DS group than in the control group. The loss of harmonious motion pattern (disordered motion pattern) at L4-L5 was well-revealed in the DS group II.

CONCLUSIONS

Motion analyses using cineradiography helped to explain the phenomena of lumbar spine kinematics. Based on continuous dynamic-motion analysis with cineradiography, large f-e angle and disordered motion pattern during the flexion-backward course in the DS group I was considered to be caused by segmental instability. The decreased translation and disordered motion pattern throughout the flexion course in the DS group II was considered to be caused by restabilization.

Population pharmacokinetics of tacrolimus in adult recipients receiving living-donor liver transplantation

OBJECTIVE

To characterize the pharmacokinetics of tacrolimus in adult recipients receiving living-donor liver transplantation (LDLT).

METHODS

Thirty-five patients were given tacrolimus as 18- to 60-h intravenous infusions after surgery, followed by a 4-week course of oral dose therapy (at 0900 hours and 2100 hours). Blood samples were collected daily in the morning (0800 hours) beginning the day after surgery. Whole blood concentration data were evaluated by nonlinear mixed-effect modeling using the program NONMEM and were characterized using a one-compartment model.

RESULTS

The clearance (CL, l h(-1)) was related to the grafted hepatic weight, postoperative days (POD), and hepatic and renal dysfunction. Interindividual variabilities in CL, volume of distribution (V), and bioavailability (F) were 57.4%. 39.7%, and 63.0%, respectively, and the correlation between individual CL and F was 0.776. Residual intraindividual variability was 2.9 ng ml(-1). Based on the estimated final parameters, a typical recipient of LDLT with grafted hepatic weight of 600 g and normal hepatic and renal function would have a CL of 0.737 l h(-1) on POD 0 and 1.14 l h(-1) on POD 30, V of 1.52 l kg(-1) and F of 6.8%.

CONCLUSIONS

Nonlinear mixed-effect modeling was useful for analysis of pharmacokinetic characteristics of tacrolimus in LDLT patients. Immediately after surgery, patients receiving LDLT showed a smaller CL value than other transplant patients, and CL value increased with POD within 30 days after surgery. The estimated population pharmacokinetic parameters can be applied for a priori dosage calculations in adult patients with LDLT.

Unusual coronary artery aneurysm and acute myocardial infarction in a middle-aged man with systemic lupus erythematosus

A 55-year-old man developed acute myocardial infarction (AMI) related to a large coronary artery aneurysm and a distal coronary stenotic lesion after steroid therapy for systemic lupus erythematosus (SLE). Only 13 SLE patients with AMI caused by coronary artery aneurysms have been reported, 11 of whom were young or middle-aged women and the 2 remaining were young men. This is the first report of a middle-aged man with multiple coronary lesions.

Skew deviation as a complication of cardiac catheterization

PURPOSE

To report three patients who developed diplopia and skew deviation after cardiac catheterization.

DESIGN

Interventional case series.

METHODS

Three patients complained of diplopia after cardiac catheterization for myocardial infarction (two male patients) or aortic dissection (one female patient). Examination demonstrated skew deviation in each patient.

RESULTS

Diplopia and skew deviation were mild and resolved completely in 4 months (case 1), 16 months (case 2), and 1.5 months (case 3). Sensitive signs of minor ischemic damage to the brain stem that cause such disorders are not detectable by neuroimaging.

CONCLUSION

Rarely, cardiac catheterization may be complicated by diplopia and skew deviation.

Antibody against oxidized low density lipoprotein may predict progression or regression of atherosclerotic coronary artery disease

OBJECTIVES

This study aimed to elucidate whether an antibody against oxidized low density lipoprotein (anti-Ox-LDL) could predict short-term coronary artery atherosclerotic lesion progression.

BACKGROUND

It is still controversial whether higher levels of the anti-Ox-LDL titer are associated with atherosclerotic coronary artery disease.

METHODS

In 52 patients undergoing coronary angioplasty and six-month follow-up angiography, we performed quantitative coronary angiographic analysis of a lesion on a branch away from the intervention site vessel and assessed lesion progression or regression using the Progression-Regression score calculated as the baseline minimal lumen diameter minus the follow-up minimal lumen diameter. The serum anti-Ox-LDL titer was measured using an enzyme-linked immunosorbent assay method just before the initial angiography in all patients.

RESULTS

The anti-Ox-LDL titer was 16.6+/-1.5 AcU/ml in the progression group (Progression-Regression score >0.15 mm; n = 20), which was significantly higher (p < 0.001) than the value of 9.5+/-1.2 in the regression group (< or =-0.15 mm; n = 14) and also higher (p < 0.01) than the value of 11.4+/-1.3 in the no-change group (-0.15 to 0.15 mm; n = 18). The Progression-Regression score was correlated with the antibody titer in all patients (r = 0.56, p < 0.001). Multiple regression analysis showed that the Progression-Regression score was independently correlated with the antibody titer (r = 0.44, p < 0.01) as well as lipoprotein (a) (r = 0.33, p < 0.05).

CONCLUSIONS

Anti-Ox-LDL may be an independent predictor of coronary atherosclerotic lesion progression in the short term.

Quantitative high-resolution microscopy on a suspended chain of gold atoms

High-resolution electron microscope images of a suspended gold chain were analyzed quantitatively. The images of the suspended gold chain were recorded on videotapes, during in situ observation in an ultra-high-vacuum electron microscope. The chain consisted of four gold atoms free from any substrate. Image simulation verified that the gold chain has a center-top geometry. The simulation also showed that the chain has no glue atoms spinning around the axis of the chain. A spinning gold atom was shown to give 50% of the stationary atom in gray scale. By comparing the noise level of the observed image and the gray scale of single atoms such as C, Si, S, Cu, and Au, we verified that the Si and S atoms have almost twice as large contrast as the noise (peak-to-peak), and C atoms have almost the same contrast as the noise level. The analysis showed it critical to detect a single Si and S atoms.

Allelic structure and distribution of two STR loci, D8S580 and D22S442, in the Japanese population

The allelic frequency and structural characteristics of two STR loci D8S580 and D22S442 were investigated using blood samples from 143 unrelated healthy Japanese individuals. Thirty-eight alleles in D8S580 locus and 13 alleles in D22S442 locus were identified. The discrimination power, heterozygosity, and the polymorphic information content of those loci displayed high values (0.98, 0.88, and 0.87 in D8S580 and 0.97, 0.86 and 0.85 in D22S442), and their frequency distributions met Hardy-Weinberg equilibrium expectations. The allelic pattern of D8S580 was complex and differentiated into three groups (group I: alleles 184-194bp; group II: alleles 203-223, 235, 239, 243, 252 and 255bp; group III: alleles 227-286bp). Most of their alleles contained five categories of repeat units (A: aaaag; B: aaag; C: aagg; D: caag; E: agaa). On the other hand, D22S442 contained only two types of repeat units (A: agga; B: aggg). The present study, hence, proves that both D8S580 and D22S442 are highly polymorphic and represent stable genetic markers applicable to forensic investigations.

Clinical significance of antibody against oxidized low density lipoprotein in patients with atherosclerotic coronary artery disease

OBJECTIVES

This study was designed to establish the clinical significance of antibodies against oxidized low density lipoprotein (anti-Ox-LDL) titer in atherosclerotic coronary artery disease (CAD).

BACKGROUND

Oxidative modification of LDL, which plays a key role in the development of atherosclerosis, induces immunogenic epitopes in the LDL molecule, and the presence of anti-Ox-LDL has been demonstrated in human sera.

METHODS

Anti-Ox-LDL titer was measured by enzyme-linked immunosorbent assay in 108 patients who had angiographically verified CAD, and 31 patients who had chest pain but no significant CAD, as controls.

RESULTS

The anti-Ox-LDL titer was higher (p < 0.01) in patients with multivessel CAD (19.4 +/- 10.1 AcU/ml, n = 68) than in the controls (9.8 +/- 4.1). However, no significant difference was shown between the single-vessel CAD group (15.1 +/- 6.4, n = 40) and the controls, or between the multivessel CAD group and the single-vessel CAD group. The titer was higher in patients with unstable angina (21.5 +/- 11.8 AcU/ml, n = 20, p < 0.01), or in patients with acute myocardial infarction (23.1 +/- 12.0, n = 20, p < 0.01) than in patients with stable-effort angina or old myocardial infarction (12.2 +/- 8.6, n = 68). Multiple logistic regression analysis indicated that the anti-Ox-LDL titer most powerfully discriminated CAD patients from controls (odds ratio [OR]: 1.20, 95% confidence interval [CI]: 1.07-1.33, p = 0.0006) and acute coronary syndrome from chronic CAD (OR: 1.09, 95% CI: 1.04-1.14, p = 0.0008).

CONCLUSIONS

Serum anti-Ox-LDL titer not only can predict a presence of atherosclerotic CAD but also may be a marker of plaque instability. Low density lipoprotein oxidation may play an important role in the development of plaque instability.

Immunological response to oxidized LDL occurs in association with oxidative DNA damage independently of serum LDL concentrations in dyslipidemic patients

Oxidative modification of LDL induces immunogenic epitopes in the LDL molecule, and the presence of antibodies against oxidized LDL (anti-Ox-LDL) has been demonstrated in human sera. However, little is known about the clinical significance of anti-Ox-LDL. To elucidate a clinical relationship between the immunological response to oxidized LDL and cellular oxidative stress, we measured serum titers of anti-Ox-LDL in 45 unselected patients with hypercholesterolemia and serum 8-hydroxy-2'-deoxyguanosine (8-OHdG), considered a biomarker of the oxidative damage to DNA. The anti-Ox-LDL titer was not correlated with the serum LDL-C concentration, but was correlated with the 8-OHdG concentration (r = 0.300, P < 0.05) in a simple linear regression. Multiple regression analysis indicated that 8-OHdG was independently correlated with anti-Ox-LDL (r = 0.429, P < 0.05), but no other variables, including LDL-C concentrations and smoking habit, were correlated with anti-Ox-LDL. In 16 subgroup patients, the concentrations of TC, TG and LDL-C decreased and the HDL-C concentration increased after cholesterol-lowering therapy with fluvastatin. In addition, both the anti-Ox LDL titer (14.0 +/- 9.5 to 11.4 +/- 6.6 AcU/ml, P < 0.05) and the 8-OHdG concentration (1.19 +/- 0.41 to 0.85 +/- 0.43 ng/ml, P < 0.05) also decreased after fluvastatin therapy. The immunological response to LDL oxidation on vascular wall tissues or cells appear to occur in association with oxidative DNA damage. The measurement of anti-Ox-LDL may be a useful indicator for lipid-lowering therapy.

Serum prostaglandin D synthase level after coronary angioplasty may predict occurrence of restenosis

Lipocalin-type prostaglandin D synthase (L-PGDS), which is responsible for the biosynthesis of PGD2, has recently been found to be present in the atherosclerotic plaque of the human coronary artery and also to be secreted in human serum. We measured the serum L-PGDS level and compared it with the expressions of the platelet membrane surface glycoprotein and neutrophil adhesion molecule in patients undergoing PTCA. The L-PGDS level significantly decreased (P < 0.01) and the platelet surface expression of CD62P (P-selectin) significantly increased (P < 0.01) immediately after PTCA in the coronary sinus blood. Both changes were inversely correlated (R = -0.72, P < 0.001). Although the L-PGDS level in the coronary sinus blood remained equivalent to the baseline level in patients who experienced restenosis, the level increased over the baseline level (P < 0.01) at 48 h after PTCA in patients without restenosis. Neutrophil surface expression of CD11b (alpha subunit of Mac-1) significantly increased at 24 h (P < 0.01) to 48 h (P < 0.001) after PTCA in the coronary sinus blood in patients with restenosis but the change showed less significant in patients without restenosis. The changes in the L-PGDS level and the CD11b expression at 48 h after PTCA were inversely correlated (R = -0.55, P < 0.05). An increased serum L-PGDS level at 48 h after PTCA possibly predicts the avoidance of late restenosis. It is suggested that reduction in PGD2 synthesis triggers platelet activation and that a subsequent increase in the PGD2 synthesis suppresses inflammatory reaction at the intervention site indicated by neutrophil activation and inhibits development of restenosis. Pharmacological or biological intervention that increases endogenous PGD2 synthesis should be tested as a new strategy to prevent restenosis.

The structure, frequency, and forensic application of the STR locus D16S543 in the Japanese population

D16S543 is a complex STR locus consisting of five types of repeat units. The frequency distribution and genetic characteristics of this locus in Japanese were investigated using blood samples from 124 unrelated Japanese and 15 families. Alleles were detected using denatured polyacrylamide gels followed by automated analysis on an ABI 373 sequencer using Genescan software 672. Twenty-one alleles were identified, ranging in size from 281 to 489 bp. An allelic ladder containing the 21 alleles was constructed and used as a typing standard. The repeat unit arrays allowed the 21 alleles to be classified into three distinct groups, including alleles 1 to 7 in group I, alleles 8 to 14 in group II, and alleles 15 to 22 in group III. The alleles in group II were characterized by the insertion of one repeat unit of CAGG, one of AAAG, and three of AAGG, while the group III alleles differed from those of groups I and II by the insertion of a total of 32 repeat units ranging in 5 types. Within each group, the alleles differed from each other only in one 5' side tetranucleotide AAGG. The power of discrimination (Pd) and the estimated heterozygosity were calculated to be 0.989 and 0.934, respectively. Typing of this locus was successfully applied in four old forensic materials. The study presented herein demonstrates that D16S543 is a highly polymorphic and applicable locus in Japanese.

Efficient shoot regeneration from hairy roots of Antirrhinum majus L. transformed by the rol type MAT vector system

 Eleven independent GUS-positive hairy roots were induced by co-cultivation of leaf explants of Antirrhinum majus L. with Agrobacterium tumefaciens strain GV2260 containing the rol type MAT vector pNPI702. The MAT vector pNPI702 possesses a GUS gene under the 35 S promoter and a removal element in which the 7.6-kb DNA fragments containing the rolA, B, C and D genes and recombinase gene with a 35 S promoter are located between two directly oriented recombination site sequences. A total of 326 adventitious shoots regenerated from 11 independent hairy root lines cultured on 1/2MS medium without plant growth regulators at 25  °C under a 16/8 h (day/night) photoperiod after 8 weeks of stock-culture of hairy roots and 4 weeks of culture of the green segments of hairy roots. Regenerated plants showed either a normal or dwarf morphology. GUS activity was observed in the hairy roots and regenerated shoots. The presence of the GUS gene in the regenerated, morphologically normal plants was confirmed by PCR analysis.

Inhibition of Tissue-Bound Semicarbazide-Sensitive Amine Oxidase by Two Haloamines, 2-Bromoethylamine and 3-Bromopropylamine

Various mammalian tissues contain membrane-bound amine oxidase termed semicarbazide-sensitive amine oxidase (SSAO). A variety of compounds has been identified as relatively selective SSAO inhibitors, but those inhibitors currently available also inhibit monoamine oxidase (MAO). In the present study, inhibitory properties of 2-bromoethylamine (2-BEA) and 3-bromopropylamine (3-BPA) toward rat lung-bound SSAO have been studied. Regardless of preincubation, 2-BEA could not appreciably inhibit MAO-A and MAO-B activity, but 3-BPA at relatively high concentrations inhibited only MAO-B activity. 3-BPA was a competitive and reversible SSAO inhibitor with a Ki value of 17 microM regardless of preincubation. In contrast, without preincubation, 2-BEA competitively inhibited SSAO activity with the Ki value of 2.5 microM and after preincubation, the mode of inhibition changed to be noncompetitive, indicating irreversible inhibition after the preincubation. Dialysis experiments with 2-BEA-pretreated homogenate resulted in no recovery of SSAO activity even after overnight dialysis. A decreased rate of SSAO inhibition under N2 atmosphere to that obtained under O2 was produced upon preincubation of enzyme with 2-BEA, suggesting that oxidized intermediate was necessary for its inhibitory activity. Thus, 2-BEA first interacts with SSAO to form a reversible complex with a subsequent reaction, leading this complex to the covalently bound enzyme-inhibitor adduct. The data analyzed by the plot of 1/k' vs 1/2-BEA concentrations intersected on the y-axis indicate that the inhibition by 2-BEA is not mediated by a bimolecular reaction; thus it is not an affinity-labeling agent, but a suicide SSAO inhibitor. 2-BEA may be employed as a useful compound in the studying SSAO.