[Relationship between tuberculin reaction and Fernandez's reaction among general population. II. Results obtained in the inhabitants of remote islands].
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Biomedical subjects
Publications and source records attributed to M Maeda.
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We developed a novel chemiluminescent assay of beta-D-galactosidase (beta-gal) based on the chemiluminescence of indole. 5-Bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (X-gal) was used as a substrate for beta-gal and also as a light emitter. X-gal was hydrolysed by beta-gal to liberate free indoxyl, followed by oxidation to indigo dye, and simultaneously produces hydrogen peroxide (H2O2). H2O2 reacts with the residual X-gal in the presence of horseradish peroxidase (HRP) to emit light. The measurable range of beta-gal obtained by this method was 6 x 10(-14) mol/L to 6 x 10(-11) mol/L; the detection limit was 3 amol/assay. This chemiluminescent assay could be applied to an enzyme immunoassay of thyroxine using beta-gal as the enzyme label.
We have screened about 100 thiourea derivatives in order to develop a sensitive chemiluminescence detection for luminol derivatives. Among these derivatives, we found a new compound, 2-(3-methylthioureido) thiazole, that could be used to measure luminol in the presence of hydrogen peroxide (H(2)O(2)). The detection limits of luminol and N-(4-aminobutyl)-N-ethylisoluminol (ABEI) were 10 fmol and 100 fmol, respectively. The mechanism of proposed chemiluminescence reaction was studied by electron spin resonance (ESR) with and without superoxide dismutase (SOD) and the addition of ethanol. The results showed that 2-(3-methylthioureido) thiazole has the ability to generate hydroxyl radical from H(2)O(2), and produces intense chemiluminescence in the presence of luminol. The proposed novel chemiluminescence reaction for luminol and luminol derivatives was applied to a high performance liquid chromatography (HPLC) assay for amino compounds.
Luminol (3-aminophthaloylhydrazine) is well known as a chemiluminescent reagent that can be used to measure peroxidase (POD) activity. We have developed a more sensitive assay for POD using a new chemiluminescent reagent based on 10,10'-dimethyl-9, 9'-biacridinium nitrate (lucigenin). This new reagent was obtained from lucigenin by light irradiation in an organic polar solvent such as N,N-dimethylacetamide (DMAc). The detection limit for POD activity using this reagent is 10(-19) mol/assay. In an application for enzyme immunoassay based on a POD label, we were able to detect human alpha-fetoprotein (AFP) at 1pg/mL. The characterization of this chemiluminescent reagent was obtained by optical measurements, and the formation of lucigenin charge transfer complex (CT-complex) was confirmed. We also investigated the stability of lucigenin CT-complex as a chemiluminescent reagent for the measurement of POD activity, and confirmed that the reagent was stable for more than a year.
This paper reports on our study using several optical filters known to be efficient in separating compounds having various levels of maximum luminescence, to separate information from three kinds of Luciola lateralis luciferase with a maximum luminescence of 559 nm, 604 nm and 607 nm. Simultaneous luminescence of Luciola lateralis luciferase was determined by measuring the luminescence through a band pass filter or sharp cut filter (BPB50, 53, 58, No.58, SC58, 60, 62, 64). It was possible to determine luciferase with a maximum luminescence lambda(max) of 559 nm (yellow-green) utilizing the band pass filter (BPB 50), described here. Meanwhile, luciferase with a lambda(max) of 607 nm (red) could be determined by calculations based on the bioluminescent intensity through the band pass filter and sharp cut filter (SC58). In addition, we also applied a simultaneous bioluminescent enzyme immunoassay of pepsinogen I (PGI) and pepsinogen II (PGII) in which two kinds of biotinylated luciferase (Luciola lateralis) labelled as an enzyme producing yellow-green light (lambda(max) = 559 nm) and red light (lambda(max) = 607 nm) were used. In the proposed method, PGI and PGII in serum were simultaneously captured in a sandwich-type immune reaction between anti-PGI and anti-PGII monoclonal antibody-coated magnetic particles, and streptavidin-biotinylated luciferase biotinylated anti-PGI and anti-PGII monoclonal antibodies triplexes, respectively. The result was a calibration range for PGI of 2-200 ng/mL, and for PGII of 1-100 ng/mL. In conclusion, the correlation of PG values in serum between the proposed method (simultaneous assay) and an individual specific bioluminescent immunoassay (specific assay) were satisfactory.
We developed a sensitive chemiluminescent sandwich-type enzyme immunoassay (CL-EIA) of alpha-fetoprotein (AFP) using beta-D-galactosidase (beta-gal) as a label and 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside as a substrate. The CL-EIA for AFP was performed using two monoclonal antibodies, one antibody is labelled with beta-gal, the other is coated onto the inside surface of a polystyrene tube. The detection limit for AFP was 0.5 ng/mL, equivalent to 10 pg/assay tube. The coefficient of variation for within and between assay imprecision were 2.0%-4.9% (n = 10) and 4.4%-9.8% (n = 5), respectively. AFP values in serum determined by this method correlated well with those obtained by radioimmunoassay (n = 26, r = 0.99). This sensitive AFP assay can be performed within 4 h and can be used as a routine assay in clinical diagnosis.
We have developed a chemiluminescent flow injection method for analysis of bile acid, glucose and ATP using the chemiluminescent assay of NADH using 1-methoxy-5-methylphenazinium methyl sulphate (1-MPMS)/isoluminol(IL)/microperoxidase (m-POD) system and immobilized enzyme reactors such as 3 alpha-hydroxysteroid dehydrogenase, glucose-dehydrogenase, hexokinase and glucose-6-phosphate dehydrogenase. The standard curves were obtained in the range of 5-100 pmol for bile acid, 0.5-5.0 nmol for glucose and 10(-7)-10(-5) mol/L for ATP. The coefficient of variation for each assay was not more than 4.1% for bile acid, 2.3% for glucose and 5.3% for ATP, respectively.
The chemiluminescent reaction of lucigenin with various reducing sugars and reducing compounds has been studied. It was found that dihydroxyacetone gave the most intense chemiluminescence (CL). We have developed highly sensitive chemiluminescent methods for alkaline phosphatase (ALP) based on the production of dihydroxyacetone using NADP+ or glycerol-3-phosphate as substrate. The detection limits for ALP using each substrate were 1.25 x 10(-19) mol/assay and 2.5 x 10(-19) mol/assay, and the coefficient of variation (n = 7) was 2.8% and 3.7%, respectively. We have also applied the method using NADP+ as substrate in enzyme immunoassays (EIA) for cholecystokinin (CCK) and human chorionic gonadotropin (hCG). CCK-8 (octapeptide sulphated form of a carboxy terminal fragment of CCK) concentrations released from alimentary canal of rat were assayed using the chemiluminescent EIA (CLEIA) and a fluorimetric EIA (ALP label). The correlation between CCK-8 values obtained by these methods was y = 1.04x + 18.21, r = 0.946, n = 28. hCG values in serum and in urine were measured. The correlation between hCG values in serum samples obtained using the CLEIA and a time-resolved fluoroimmunoassay (TR-FIA), and in urine samples obtained using the CLEIA and the fluorimetric EIA using ALP were satisfactory. The correlations were y = 1.00x - 0.04, r = 0.997 (n = 51) and y = 1.00x - 0.03, r = 0.999 (n = 10), respectively.
We have developed a fully automated discrete chemiluminescent heterogeneous enzyme immunoassay system called Luminomaster. The characteristics of this analyser are: 120 test/h throughput, 14 test menu, wide dynamic range, automated sample dilution, automatic retest, communication with a host central processing unit (CPU) and connection with sample transfer system.
Allele-specific PCR for E. coli O157 was conducted with primers specific to verotoxin genes, verotoxin 1 (VT1) and verotoxin 2 (VT2). VT is an important cause of haemorrhagic colitis (HC) and haemolytic uraemic syndrome (HUS) worldwide. We developed a simple, rapid bioluminescent detection method for E. coli O157. The method is based on the determination of pyrophosphoric acid (PPi) released during allele-specific PCR. Thus, released PPi is converted to ATP by ATP sulphurylase and the concentration of ATP is determined using the firefly luciferase reaction. As a result, VT1, VT2 and DNA with VT1/VT2 were clearly identified by this method. This protocol, which does not require expensive equipment, can be utilized to monitor the PCR product rapidly. Additionally, this methodology can be used as a high-throughput approach for measuring PCR products.
The availability of new therapeutic interventions, including neuroprotective agents and endovascular thrombolysis, has given new hope to patients suffering an acute stroke. Early intervention remains a key factor in the effectiveness of these new and traditional treatments. More importantly, the capability to assess the viability and reversibility of the ischemic tissue became essential for better delineation and differentiation of infarcted versus ischemic tissue and patient management. Abnormal MR imaging (MRI) findings during acute stroke usually reflect the underlying pathophysiologic changes, which can be classified into three sequential stages: (a) hypoperfusion, (b) cellular dysfunction and (c) breakdown of the blood-brain barrier. The first stage is a kinetic phenomenon (not biologic) and, therefore, can be detected immediately. Contrast agents accentuate the abnormal flow kinetics and facilitate the early diagnosis of ischemia using either conventional MRI or newly developed echo-planar perfusion imaging (EPPI). The demonstration of abnormal arterial or parenchymal enhancement on conventional MRI during acute stroke provides the earliest sign of vascular occlusion/stenosis. EPPI, in contrast, provides information related to microcirculation (< 100 microns) and tissue reserve (cerebral blood volume) that cannot be obtained by conventional angiography and is directly related to the target end-organ. Further information obtained from both contrast MRI and EPPI may have a predictive value in the clinical outcome of acute stroke patients.
The purpose of this study was to evaluate cerebral perfusion with T2*-weighted dynamic MRI in the area around the infarcted core. We examined seven patients with subacute cerebral infarction. After bolus injection a gadopentetate dimeglumine, a series of gradient-echo images were recorded in a selected slice. From these images, concentration-time curves were created on a region-of-interest (ROI) basis around infarction for calculating relative regional cerebral blood volume (rrCBV). Brain perfusion single photon emission computed tomography (SPECT) study also was performed with intravenous injection of 123I-labeled N-isopropyl-p-iodoamphetamine (123I-IMP). All patients showed prolonged signal decrease in the area around the infarcted core. ROI analysis showed significantly increased rrCBV compared to the normal side (P < .01, paired t test). The 123I-IMP SPECT study showed that these areas had decreased cerebral blood flow. Theses findings suggest compensatory vascular dilatation due to decreased perfusion pressure. T2*-weighted dynamic MRI is a useful method for detecting compensatory vasodilatation of ischemic insult in the peri-infarcted area.
In atrial fibrillation, the relation between the rhythm and volume of the pulse has long been of interest. However, changes in preload in this condition have not been fully addressed since beat to beat measurement of filling volume have been difficult until recently. In the present study, we evaluated left ventricular outflow and inflow velocity using pulsed Doppler echocardiography and correlated these results with the R-R interval in the individual patient. The study population consisted of 12 patients with atrial fibrillation, aged 36 to 69 years (mean 54 years). The etiology of atrial fibrillation was idiopathic in 10 and 2 patients had dilated cardiomyopathy. Stroke and filling volume were calculated as a pruduct of the flow velocity integral of left ventricular outflow and inflow velocity, and the cross-sectional area of aortic and mitral annulus, respectively. In 10 patients with idiopathic atrial fibrillation, significant positive correlations were observed between the preceding R-R interval and both the stroke volume and the filling volume of the preceding beat when the R-R interval was shorter than 600 msec. Stroke volume and filling volume of the preceding beat were almost constant, independent of the preceding R-R interval when the preceding R-R interval was longer than 600 msec, the interval necessary for the completion of the preceding rapid filling. In the same preceding R-R interval, a larger stroke volume was observed in a shorter pre-preceding R-R interval. In 2 patients with dilated cardiomyopathy no relationship could be observed between the preceding R-R interval and the filling volume of the preceding beat or the stroke volume. In patients with a normally functioning left ventricle (idiopathic atrial fibrillation), reduced cycle length and filling volume in the preceding cardiac cycle appear to be the underlying cause of the regulation of stroke volume, dependent on Starling's law. However, in patients with dilated cardiomyopathy no significant correlation was observed between the preceding R-R interval and both the filling volume of the preceding beat and the stroke volume. In these patients the left ventricle may have limited contractile reserve and altered diastolic re-coil forces possibly due to degenerative changes of myocardium. Pulsed Doppler echocardiography provides a non-invasive method of evaluating the instantaneous changes in left ventricular flow dynamics caused by atrial fibrillation and understanding its fundamental mechanism.
Transcatheter hepatic segmental arterial chemoembolization using Lipiodol mixed with an anticancer drug followed by the injection of Gelfoam particles, introduced into the tumor-bearing hepatic segment as the target area (segmental Lipiodol-TAE), was carried out in 54 patients with hepatocellular carcinoma (HCC), 7 of whom were later resected. In 5 of the resected 7 cases, complete necrosis was histologically verified. No death due to HCC was encountered in 47 nonoperated cases, and better therapeutic results were obtained with segmental Lipiodol-TAE. It was concluded that this technique does not adversely affect normal tissues, and it does reinforce the effect of TAE.
Thirty patients with atherosclerotic stenoses or occlusions of iliofemoral arteries were treated from the contralateral approach using a newly designed J-shaped sheath. Seven patients with stenoses and one with an occlusion were successfully dilated with balloon angioplasty. Twenty-two patients with occlusions were treated with urokinase infusion, 16 of whom received coaxial infusion with the J-shaped sheath and catheter. Complete thrombolysis was achieved in 18 patients. The treatment success rate was 100% in the stenotic group and 83% in the occlusion group. Initially, J-shaped sheaths were useful for treatment of iliofemoral artery lesions from the contralateral femoral artery.
PURPOSE: To evaluate the feasibility of combining placement of a transjugular intrahepatic portosystemic shunt (TIPS) and transcatheter hepatic segmental artery chemoembolization with Lipiodol (Seg-Lp-TAE) in patients with cirrhosis, esophagogastric varices, and hepatocellular carcinoma (HCC). METHODS: Five patients with bleeding or large, high-flow esophagogastric varices and HCC were treated by TIPS and Seg-Lp-TAE. RESULTS: The mean portosystemic pressure gradient decreased from 20.8 cm H2O to 7.8 cm H2O after TIPS. The direct portogram and endoscopic examination revealed reduction of varices. At 6 months, one shunt had functionally occluded and could not be reopened; the other TIPS remained functional. Follow-up CT and the changes of alpha fetoprotein indicated effective therapy of Seg-Lp-TAE for HCC. Four patients are in stabile clinical condition at 9, 6, 1, and 1 months after the combined therapy; one died after 14 months due to decompensated liver cirrhosis. CONCLUSION: The combined therapy of TIPS and Seg-Lp-TAE will become a new interventional approach for patients with HCC and esophagogastric varices.
Total correction was performed in a case of complete transposition of the great arteries (TGA) with severe pulmonary vascular obstructive disease (PVOD). Although severe pulmonary hypertension remained after surgery, oxygenation was continued for 15 months, which included a shift to at-home oxygen inhalation therapy (HOT). Cardiac catheterization 15 months after surgery demonstrated that pulmonary hypertension was greatly improved. For patients in whom the palliative Mustard operation is considered due to severe PVOD on the basis of lung biopsy diagnosis, total correction of TGA is possible by employing HOT after surgery.
We report an unusual anomaly of the upper body venous drainage in a patient with visceroatrial situs inversus. The patient had a persistent right superior vena cava draining into the left-sided right atrium by way of the coronary sinus, with the absence of the left superior vena cava associated with atrioventricular discordant levocardia, pulmonary atresia, and ventricular septal defect.