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H Toyama

Publications and source records attributed to H Toyama.

At least 91 records · Page 5Linked to original sources
PubMed1996

Evaluation of the brain uptake properties of [1-11C]labeled hexanoate in anesthetized cats by means of positron emission tomography.

Positron emission tomography (PET) was performed on the cat brain to characterize [1-11C]hexanoate and other [1-11C]labeled short and medium-chain fatty acids as a tracer of fatty acid oxidative metabolism. After an intravenous injection the brain uptake of [1-11C]hexanoate reached a peak followed by rapid washout until 2 min (first phase). Subsequently the total brain uptake was again increased and reached to a peak 7-10 min after tracer injection (second phase). The blood radioactivity of unmetabolized [1-11C]hexanoate was rapidly decreased and almost eliminated within the first 2 min, whereas the blood radioactivity of [11C]CO2/HCO3- was gradually increased and reached a peak approximately 5 min after tracer injection. As the effect of circulating [11C]CO2/HCO3- was examined by a bolus intravenous injection of [11C]CO2/HCO3-, the brain uptake of [11C]CO2/HCO3- was rapidly increased right after the injection and changed parallel to the blood level of [11C]CO2/HCO3-. These results suggest that, in contrast to the previous mouse data, the time-activity curve in the cat brain following intravenous injection of [1-11C]hexanoate has a biphasic pattern, the second phase being determined by peripherally originating [11C]CO2/HCO3-, and therefore does not reflect the metabolism of 11C-labeled fatty acid in the brain.

Animals↗
PubMed1996

A human friendly reporting and database system for brain PET analysis.

We have developed a human friendly reporting and database system for clinical brain PET (Positron Emission Tomography) scans, which enables statistical data analysis on qualitative information obtained from image interpretation. Our system consists of a Brain PET Data (Input) Tool and Report Writing Tool. In the Brain PET Data Tool, findings and interpretations are input by selecting menu icons in a window panel instead of writing a free text. This method of input enables on-line data entry into and update of the database by means of pre-defined consistent words, which facilitates statistical data analysis. The Report Writing Tool generates a one page report of natural English sentences semi-automatically by using the above input information and the patient information obtained from our PET center's main database. It also has a keyword selection function from the report text so that we can save a set of keywords on the database for further analysis. By means of this system, we can store the data related to patient information and visual interpretation of the PET examination while writing clinical reports in daily work. The database files in our system can be accessed by means of commercially available databases. We have used the 4th Dimension database that runs on a Macintosh computer and analyzed 95 cases of 18F-FDG brain PET studies. The results showed high specificity of parietal hypometabolism for Alzheimer's patients.

Alzheimer Disease↗
PubMed1996

A distribution study of 11C platelet-activating factor (PAF) analogs in normal and tumor-bearing mice.

As a preliminary study to image platelet-activating factor (PAF) receptors in vivo, comparative study of biodistribution between 1-O-hexadecy1-2-O-N, N-dimethylcarbamoyl-sn-glycero-3-phosphocholine [choline-methyl-11C](L-[11C]dimethylcarbamoyl-PAF) and nonspecific PAF analog, 3-O-hexadecyl-2-O-N,N-dimethylcarbamoyl-sn-glycero-1-phosphocholine [choline-methyl-11C](D-[11C]-dimethylcarbamoyl-PAF) was carried out in both normal and tumor-bearing mice. Higher accumulation of L-[11C]dimethylcarbamoyl-PAF than D-[11C]dimethylcarbamoyl-PAF was observed in normal mice spleen. The co-administration of PAF antagonists dose-dependently reduced the radioactivity level of the L-isomer only in the spleen. In mice bearing Ehrlich tumors and Sarcoma 180, more L-than the D-[11C]-isomer was accumulated in the tumor and spleen. We found that specific accumulation sites for L-[11C]dimethylcarbamoyl-PAF exist in the spleen and tumors than in other tissues. Moreover, the comparison of accumulation between L- and D-[11C] dimethylcarbamoyl-PAF would be a useful procedure for estimation of PAF receptors in vivo.

Animals↗
PubMed1996

A multicenter validation of regional cerebral blood flow quantitation using [123I]iodoamphetamine and single photon emission computed tomography.

Recently, two methods have been proposed for regional cerebral blood flow (rCBF) quantitation using [123I]iodoamphetamine (IMP) and single-photon emission computed tomography (SPECT). The table look-up (TLU) method has been shown to provide both rCBF and volume of distribution, Vd, images from two SPECT scans, while a single-scan autoradiographic (ARG) technique provided rCBF using a fixed and assumed Vd. In both methods, a single blood sample was referred to calibrate the previously determined standard input function. The present multicenter project was designed to evaluate the accuracy of both methods for use as clinical investigative tools. Ten independent institutions performed [123I]IMP-SPECT studies according to both methods in 76 subjects (10 normal volunteers, 32 patients with cerebrovascular disease, and 34 patients with other diseases). Calculated rCBF values were compared with those obtained by the following reference methods available in the participating institutions; [15O] H2O positron emission tomography (PET) (five institutions), [133Xe]SPECT (four institutions), and the [123I]IMP microsphere method (three institutions). Both ARG and TLU methods provided rCBF values that were significantly correlated with those measured by the [15O] H2O PET technique (p < 0.001 for all subjects; overall regression equation, y = 15.14 + 0.54x) and those measured by the [123I]IMP-microsphere method (p < 0.001 for all subjects: y = 2.0 + 0.80x). Significant correlation (p < 0.05) was observed in 18 of 24 subjects studied with the [133Xe] SPECT reference technique (overall regression equation, y = 15.0 + 0.55x). Mean cortical gray matter rCBF in a group of normal subject was 43.9 +/- 3.3 and 43.4 +/- 2.0 ml/min/100 g for the ARG and TLU methods, respectively. Regional Vd of [123I]IMP estimated by the TLU method was 45 ml/ml +/- 20% in the normal cortical region. Close agreement between ARG and TLU rCBF values was observed (y = -3.21 + 1.07x, r = 0.97), confirming the validity of assuming a fixed Vd in the ARG method. Results of this study demonstrate that both the ARG and TLU methods accurately and reliably estimate rCBF in a variety of clinical settings.

Adolescent↗
PubMed1996

Surgical treatment of refractory venous stasis ulcer due to a severe impairment of calf muscle pump function: evaluation by air plethysmography. A case report.

The authors encountered a forty-nine-year-old man with a lower limb ulcer refractory to intensive conservative therapy. No varicose vein was found anywhere, and the usual phlebographies and foot venous pressure measurement failed to diagnose it as a venous stasis ulcer. A direct phlebography method developed by the authors, in which a thin catheter is inserted into the deep vein, disclosed a reflux of the popliteal vein or a deep muscle branch from which an incompetent perforator arose toward the superficial vein above the ulcer. Air plethysmography (APG) showed a severe impairment of the calf muscle pump function. He underwent a subfascial ligation of two incompetent perforators together with a stripping of the great saphenous vein passing under the ulcer. Postoperatively, this ulcer was cured in an early phase, and the calf muscle pump function showed improvement in the APG.

Hemodynamics↗
PubMed1996

[Evaluation of the clinical usefulness of super dynamic 99mTc-HM-PAO SPECT in ischemic cerebrovascular disease--detection of hypo- and hyperperfusion area].

The purpose of this study is to assess the clinical usefulness of super dynamic SPECT of 99mTc-HM-PAO. Six patients with unilateral occlusion of middle cerebral artery (MCA) or internal carotid artery (ICA) in the chronic phase, and 5 patients with subacute cerebral infarction were studied. We used a ring-type SPECT "HEADTOME." Two types of collimator were used: a high sensitivity (HS) collimator for super dynamic scan and a high resolution (HR) collimator for static scan. First, the intravenous constant infusion of 99mTc-HM-PAO (925-1480 MBq) for 1 minute was started. After 30 seconds from the beginning of the injection, we performed the 12 seconds/frame super dynamic SPECT for 2 minutes. Then, the static SPECT for 10 minutes was done. For semiquantitative analyses, differential percentage of regional activity between affected and non-affected hemispheres was calculated in the 6th frame image of super dynamic SPECT and static SPECT image. In all 6 patients with unilateral occlusion of MCA and ICA, super dynamic SPECT images showed the better contrast of low perfusion areas in comparison with the static SPECT images. In 5 patients with subacute cerebral infarction who showed focal hyperactivities on static SPECT, focal hyperactivities (hyperperfusion or hyperemia) were displayed in 3 cases, whereas, focal hypo- or isoactivities (hypo- or isoperfusion) were shown in 2 cases on super dynamic SPECT. However, all patients with subacute cerebral infarction showed hyperfixation on static SPECT as compared with super dynamic SPECT. Although the image quality on super dynamic SPECT is not as high as that on static SPECT, cerebral hemodynamics would be detected with less backdiffusion of 99mTc-HM-PAO from the brain to blood, and with less accumulation of hydrophilic components in subacute infarct region. In conclusion, super dynamic SPECT in early distribution of 99mTc-HM-PAO using dedicated SPECT device might be helpful to detect cerebral perfusion close to true cerebral blood flow distribution.

Aged↗
PubMed1996

[Basic study on relationship between estimated rate constants and noise in FDG kinetic analysis].

For accurate estimation of the rate constants in 18F-FDG dynamic study, the shape of the estimation function (phi) is crucial. In this investigation, the relationship between the noise level in tissue time activity curve and the shape of the least squared estimation function which is the sum of squarred error between a function of model parameters and a measured data is calculated in 3 parameter model of 18F-FDG. In the first simulation, by using actual plasma time activity curve, the true tissue curve was generated from known sets of rate constants ranging 0.05 < or = k1 < or = 0.15, 0.1 < or = k2 < or = 0.2 and 0.01 < or = k3 < or = 0.1 in 0.01 step. This procedure was repeated under various noise levels in the tissue time activity curve from 1 to 8% of the maximum value in the tissue activity. In the second simulation, plasma and tissue time activity curves from clinical 18F-FDG dynamic study were used to calculate the phi. Results are: (1) In the noise-free case, because the global minima is separated from neighboring local minimums, it was easy to find out the optimum point. However, with increasing noise level, the optimum point was buried in many neighboring local minima. Making it difficult to find out the optimum point. (2) The optimum point was found within 20% of the convergence point by standard non-linear optimization method. (3) The shape of phi for the clinical data was similar to that with the noise level of 3 or 5% in the first simulation. Therefore direct search within the area extending 20% from the result of usual non-linear curve fitting procedure is recommended for accurate estimation of the constants.

Deoxyglucose↗
PubMed1996

Assessment of antioxidative ability in brain: technetium-99m-meso-HMPAO as an imaging agent for glutathione localization.

UNLABELLED: To visualize the regional localization of glutathione (GSH) in the brain, the relationship between the concentrations of tissue GSH and uptake of [99mTc]meso-hexamethyl propyleneamine oxime ([99mTc] meso-HMPAO) or [99mTc]d,l-hexamethyl propyleneamine oxime ([99mTc]d,l-HMPAO) was studied in mice. METHODS: The uptake of [99mTc]meso-HMPAO in the mouse brain was decreased to 35% of control paralleling the decrease in GSH content by pre-loading of diethyl maleate (DEM), an agent to reduce GSH. In contrast, pre-treatment with DEM scarcely affected the 99mTc-d,l-HMPAO uptake in the brain. RESULTS: The DEM treatment decreased the GSH content in liver, kidney, spleen, fat and lung but did not affect the uptake of [99mTc]meso-HMPAO in those tissues except lung. The images of rat brain acquired with a gamma camera showed a significant reduction of [99mTc]meso-HMPAO uptake by DEM treatment. CONCLUSION: Technetium-99m-meso-HMPAO may be a potential tool to assess GSH content and to estimate antioxidative ability in the brain.

Animals↗
PubMed1995

Synthesis and preliminary evaluation of [1-11C]hexanoate as a PET tracer of fatty acid metabolism.

The potential of [1-11C]hexanoate (11C-HA) as a radiopharmaceutical assessing fatty acid metabolism of the myocardium and brain tissues by PET studies was evaluated. 11C-HA was synthesized by the Grignard reaction of pentylmagnesium bromide and 11CO2. 11C-HA, [1-14C]acetate and [3H]deoxyglucose were simultaneously injected i.v. into mice, and the tissue distribution of the three radionuclides was measured. In the heart, high uptake and rapid clearance of 11C and 14C was found. The brain uptake of 11C was twice as high as that of 14C, and both 11C and 14C decreased slowly compared to the heart. The level of 3H increased with time in both the heart and brain. In fasting conditions, the uptake of 11C by the heart was enhanced and the level of 3H decreased with time. The brain uptake of 11C and 3H was also enhanced. The fasting conditions did not affect the distribution of 14C. The radiation absorbed dose of 11C-HA was also estimated.

Adult↗
PubMed1995

Generation mechanism and purification of an inactive form convertible in vivo to the active form of quinoprotein alcohol dehydrogenase in Gluconobacter suboxydans.

Alcohol dehydrogenase (ADH) of acetic acid bacteria is a membrane-bound quinohemoprotein-cytochrome c complex involved in vinegar production. In Gluconobacter suboxydans grown under acidic growth conditions, it was found that ADH content in the membranes was largely increased but the activity was not much changed, suggesting that such a condition produces an inactive form of ADH (inactive ADH). A similar phenomenon could be also observed in Acetobacter aceti, another genus of acetic acid bacteria. Furthermore, aeration conditions were also shown to affect ADH production; the ADH level was increased and was present as an active form under low-aeration conditions, while the ADH level was decreased and was present mainly as an inactive form under high-aeration conditions. Inactive ADH was solubilized from the membranes of G. suboxydans grown in acidic and high-aeration conditions and was purified separately from the normal, active form of ADH (active ADH). In spite of having 10 times less enzyme activity than active ADH, inactive ADH could not be distinguished from active ADH with respect to their subunit compositions, molecular sizes, and prosthetic groups. Inactive ADH, however, had a relatively loose conformation with a partially oxidized state, while active ADH had a tight conformation with a completely reduced state, suggesting that inactive ADH may lack a right subunit's interaction and that one of the heme c components may be inactivated. Reactivation from such an inactive ADH occurred either by shifting of the pH of the culture medium up during the cultivation or by incubation of the resting cells at the neutral pH region in the presence of an energy source such as D-sorbitol. Such an activation of ADH was repressed by the addition of a proton uncoupler and could not occur in the spheroplasts. Thus, the results suggest that inactive ADH could be generated abundantly under acidic growth conditions and converted to the active form at a neutral culture pH. The data also suggest that some periplasmic component may be involved in the conversion of inactive ADH into the active form by consuming some forms of energy.

Acetobacteraceae↗
PubMed1995

Three distinct quinoprotein alcohol dehydrogenases are expressed when Pseudomonas putida is grown on different alcohols.

A bacterial strain that can utilize several kinds of alcohols as its sole carbon and energy sources was isolated from soil and tentatively identified as Pseudomonas putida HK5. Three distinct dye-linked alcohol dehydrogenases (ADHs), each of which contained the prosthetic group pyrroloquinoline quinone (PQQ), were formed in the soluble fractions of this strain grown on different alcohols. ADH I was formed most abundantly in the cells grown on ethanol and was similar to the quinoprotein ADH reported for P. putida (H. Görisch and M. Rupp, Antonie Leeuwenhoek 56:35-45, 1989) except for its isoelectric point. The other two ADHs, ADH IIB and ADH IIG, were formed separately in the cells grown on 1-butanol and 1,2-propanediol, respectively. Both of these enzymes contained heme c in addition to PQQ and functioned as quinohemoprotein dehydrogenases. Potassium ferricyanide was an available electron acceptor for ADHs IIB and IIG but not for ADH I. The molecular weights were estimated to be 69,000 for ADH IIB and 72,000 for ADH IIG, and both enzymes were shown to be monomers. Antibodies raised against each of the purified ADHs could distinguish the ADHs from one another. Immunoblot analysis showed that ADH I was detected in cells grown on each alcohol tested, but ethanol was the most effective inducer. ADH IIB was formed in the cells grown on alcohols of medium chain length and also on 1,3-butanediol. Induction of ADH IIG was restricted to 1,2-propanediol or glycerol, of which the former alcohol was more effective. These results from immunoblot analysis correlated well with the substrate specificities of the respective enzymes. Thus, three distinct quinoprotein ADHs were shown to be synthesized by a single bacterium under different growth conditions.

1-Butanol↗
PubMed1995

Decline in glucose metabolism in the brain in neuronal ceroid lipofuscinosis (NCL) in English setter--evidence by positron emission tomography (PET).

Positron emission tomography scans were performed on brains of homozygous and heterozygous English setters with neuronal ceroid-lipofuscinosis (NCL) from 13 months of age to 24-25 months of age for homozygous dogs and to 38 months for heterozygous dogs, respectively. After iv injection of 18F-fluorodeoxyglucose (FDG), 7 coronal brain scans as well as sequential arterial blood samplings were performed for 45 min under pentobarbital anesthesia. From these data, three different functional images (DAR (standardized uptake value), FDG uptake (fractional uptake) and glucose uptake) were reconstructed and quantitatively analysed. In the age range from 13 to 15 months, glucose images were comparable for both homozygous and heterozygous dogs, so that no differentiation was possible between healthy and diseased dogs on the basis of PET findings. Between 18 and 24 months of age, a drastic decline in glucose metabolism was observed in homozygous dogs, while the decline in glucose utilization was very mild in this period for heterozygous dogs. Furthermore, in PET scans, cerebral atrophy and ventricular enlargement were clearly shown in homozygous dogs. Consequently at the age from 20 to 24 months, a clear differential diagnosis between healthy (heterozygous) and diseased (homozygous) dogs became possible even if the clinical symptoms were still not clear in the latter. We conclude that the biochemical alterations in the brain in canine NCL occurs and progresses very rapidly in the last quarter of their lives.

Aging↗
PubMed1995

Usefulness of hyperventilation thallium-201 single photon emission computed tomography for the diagnosis of vasospastic angina.

To establish a safe and sensitive diagnostic procedure for detecting coronary vasospasm, we utilized 201-thallium myocardial SPECT combined with hyperventilation (HV-SPECT) in 29 patients with vasospastic angina (VAP) and 11 controls. Twenty-five of 29 patients with VAP and 5 of 11 controls developed transient perfusion defects on HV-SPECT, resulting in a sensitivity and specificity calculated at 86% and 55%, respectively. Overall accuracy in identifying corresponding vessels with coronary vasospasm, respectively. Coronary vasospasm tended to be identified more accurately in the left anterior descending branch and the right coronary artery than in the circumflex branch (75%, 71% and 50%, respectively). The hyperventilation test induced ischemic ECG changes in 11 of 29 patients with VAP, yielding a sensitivity of 38%. Analyzing the washout rate of HV-SPECT in patients with VAP, both the extent and severity scores of patients with ischemic ECG changes were larger than those of patients without. No serious complications occurred during HV-SPECT. In conclusion, HV-SPECT was a safe and sensitive procedure as a primary diagnostic approach for VAP. From the results of washout analysis, HV-SPECT could detect more mild myocardial ischemia than could the ECG, and seemed quite useful especially for detecting coronary vasospasm accompanied by minimal ischemic ECG changes.

Adult↗
PubMed1995

[Evaluation of the residual functional reserve and the early regeneration after the hepatic resection using asialoglycoprotein receptor imaging agent].

99mTc-DTPA-galactosyl human serum albumin (99mTc-GSA) is a newly developed liver imaging ligand which specifically binds to asialoglycoprotein receptor on the hepatic cell surface. We investigated whether 99mTc-GSA scintigraphy was able to be used as indexes for the residual functional reserve and the early regeneration of the hepatocyte after the hepatic resection. Four patients with metastatic liver cancer, 3 patients with hepatocellular carcinoma, and 1 patient with cholangiocellular carcinoma were studied. Basically, each patient was examined 4 times (before, 3, 10, 20 days after the operation). Immediately after i.v. injection of 185 MBq (3 mg) of 99mTc-GSA, serial images and dynamic data were obtained. Serial changes of HH15, as an index of blood clearance of the tracer calculated from the uptake ratio of heart at 15 minutes to that at 3 minutes, and LHL15, as an index of hepatic accumulation calculated from the uptake ratio of liver to liver plus heart at 15 minutes after the injection were analyzed before and after hepatectomy. Three out of 4 lobectomy patients which showed increased HH15, and decreased LHL15 as compared with the preoperative data were considered to be decreased residual hepatic functional reserve. The remaining one lobectomy patient showed increased HH15, but increased LHL15 inversely. One patient of two partial resections of hepatocellular carcinoma with liver cirrhosis demonstrated transiently decreased HH15, and increased LHL15. Two patients with metastatic liver cancer (one partial resection, six partial resections) showed decreased HH15, and increased LHL15. Postoperatively increased hepatic accumulation was presumed to be increased functioning hepatocyte or transiently increased asialoglycoprotein receptor on the cell surface by up-regulation. 99mTc-GSA scintigraphy might be helpful for non-invasive method to detect the residual functional reserve and the early regeneration of the hepatocyte after the hepatic resection.

Aged↗
PubMed1995

Resting asynchronous left ventricular contraction abnormality analyzed by a phase method in spastic angina pectoris.

UNLABELLED: Quantitative phase analysis of equilibrium ventriculography was performed to study the character of left ventricular (LV) wall motion abnormalities in patients with spastic angina pectoris, who may have clinically and electrocardiographically silent ischemia combined with myocardial stunning, during rest and hyperventilation stress testing. METHODS: Phase analysis of the left ventricle at rest was performed by equilibrium radionuclide ventriculography in 13 control subjects and 36 patients with spastic angina pectoris. First-pass methodology along with hyperventilation stress testing was performed to assess spasm occurrences. Phase analysis of equilibrium multigated blood-pool scintigrams was performed to evaluate LV asynchrony at rest. RESULTS: The mean s.d. of LV phase distribution in the patients with variant and vasospastic angina was greater than that in the healthy control subjects (11.28 +/- 1.79 and 10.02 +/- 1.57 degrees versus 6.16 +/- 1.07 degrees). In addition, the mean s.d. of LV phase distribution in the variant angina group was greater than that in the vasospastic angina group. Furthermore, a linear correlation was found between the s.d. of LV phase distribution at rest and the percent decrease in ejection fraction during hyperventilation stress. CONCLUSION: Asynchronous LV contraction without significant hypokinesis was detected at rest in spastic angina pectoris. The severity of this asynchronous contraction corresponded well with decreases in ejection fraction during hyperventilation stress testing. Thus, analysis of the s.d. of LV phase distribution at rest is expected to provide useful information regarding LV asynchrony in spastic angina pectoris.

Adult↗
PubMed1995

[Quantitative analysis of individual renal function using 99mTc-DMSA scintigram--comparison with 131I-OIH renogram].

99mTc-2,3-di-mercapto-succinic acid (DMSA) is able to be used for the quantitative analysis of individual renal function by calculating the uptake ratio. The purpose of this study is to assess the clinical feasibility of DMSA uptake ratio as compared with 131I-ortho-iodo-hippuran (OIH) renogram pattern. Two hundred eleven cases (191 patients, 1 to 87 years old) with renal disorders and 4 normal volunteers (27.8 +/- 2.4 years old) were studied. Just prior to the DMSA study in the same day, OIH renogram was carried out. They were divided into 6 types by OIH renogram patterns. In 24 cases of normal renogram pattern and normal blood data who were defined as the normal group and 4 normal volunteers, DMSA uptake ratio showed negative correlation with increasing age (r = 0.61, p < 0.05). Patients of the severe impaired functioning and the non functioning patterns showed significantly decreased DMSA uptake ratios as compared with the normal pattern. There was also a significant difference in DMSA uptake between impaired functioning patterns. Compensative hemi-hypertrophy kidneys showed significantly higher DMSA uptake ratios than those of atrophic kidneys. The possibility of the quantitative analysis of the functional compensation was presumed. In conclusion, quantitative analysis of individual renal function using DMSA uptake ratio is considered to be useful to evaluate the renal functional reserve.

Adolescent↗
PubMed1995

Half-site reactivity with p-nitrophenylhydrazine and subunit separation of the dimeric copper-containing amine oxidase from Aspergillus niger.

Structural properties of dimeric (2 x 75 kDa) copper-containing amine oxidase (EC 1.4.3.6) from Aspergillus niger were studied. The enzyme treated with SDS was dissociated into subunits which showed different mobility on polyacrylamide gel without SDS. The separated subunits had no activity but a quinone moiety was detected in both by a redox-cyclic quinone staining. After titration of the enzyme with p-nitrophenylhydrazine, which showed half-site reactivity (1 mole per dimer), and SDS treatment both p-nitro-phenylhydrazone and a remaining quinone moiety were detected in each subunit. It is suggested that the half-site reactivity with phenylhydrazine is caused by conformational changes after binding of the inhibitor to any one of the active sites leading to inaccessibility of the second active site for the inhibitor. The difference in electrophoretic mobility of the separated subunits originates probably from their structural difference likely to occur outside the active site, even if the amino acid sequences of the subunits appear to be identical.

Amine Oxidase (Copper-Containing)↗