Search PubMed⌕ Search

Biomedical subjects

S Kinuya

Publications and source records attributed to S Kinuya.

At least 73 records · Page 4Linked to original sources

Inguinoscrotal lymphatic reflux detected by lymphoscintigraphy.

We performed lymphoscintigraphy with 99mTc-human serum albumin in a case of suspected lymphedema of the right leg after inguinal lymph node dissection. Dermal backflow of the leg and lymphocele at the inguinal chain were observed, and lymphatic reflux into the scrotum was also delineated. The scintigraphy could demonstrate a persistent lymphatic problem under conservative treatment, and could lead the physician to conduct surgical treatment. Scintigraphic demonstration of the inguinoscrotal lymphatic reflux has not been previously reported.

Bone Neoplasms↗

Metastatic calcification: accumulation of a bone tracer during dynamic data acquisition.

Metastatic calcification is often detected by bone scintigraphy. We recently saw metastatic calcification in the stomach and kidneys of a patient on continuous ambulatory peritoneal dialysis. Tc-99m HMDP accumulation into both organs was noted even in the first frame of dynamic data acquisition of 4 min/frame, suggesting that calcium deposits may create an aggressive process and we may obtain information on the calcium deposit rate to better understand the mechanism of metastatic calcification.

Aged↗

Technetium-99m tetrofosmin uptake in lung cancer: comparison with thallium-201.

Technetium-99m tetrofosmin and thallium-201 lung SPECT imaging were performed in a patient with adenocarcinoma of the lung. Significant activities in the lung lesion were clearly depicted on both technetium-99m tetrofosmin and thallium-201 SPECT imaging. The early uptake, delayed uptake ratios and retention indices of the tumor were 2.75, 2.39 and -1.31 for thallium-201 imaging and 3.09, 2.27 and -26.5 for technetium-99m tetrofosmin imaging, respectively. This preliminary report suggests that technetium-99m tetrofosmin may have potential as a tumor imaging agent.

Adenocarcinoma↗

Intense and prolonged Tl-201 accumulation in a slow growing bronchioloalveolar carcinoma.

Thallium-201 SPECT was performed to evaluate a pulmonary lesion in a 73-year-old male which had been considered to be an inflammatory lesion for two years. The lesion has slowly increased in size on x-CT. Tl-201 was intensely taken up and retained in the lesion, suggesting a malignant lesion. Histological examination revealed that the lesion was bronchioloalveolar carcinoma. This case suggested that Tl-201 uptake of pulmonary carcinoma would not be necessarily related to cell growth rate.

Adenocarcinoma, Bronchiolo-Alveolar↗

Effect of induced hypertension with angiotensin II infusion on biodistribution of 111in-labeled monoclonal antibody.

We investigated whether induced hypertension could enhance tumor uptake of monoclonal antibody. 111In-DTPA-A7 (IgG1 against 40kD tumor associated glycoprotein) was injected into colon carcinoma xenografted mice which were subcutaneously implanted with micro-osmotic pump containing angiotensin II (AT-II). Biodistribution was observed in groups of mice infused with AT-II at rate of 0.5 micrograms/kg/min (L) or 1 microgram/kg/min (H) and compared with a group of mice infused with saline (S). Tumor uptake of 111In-A7 in L and H was 1.32 and 1.57 times greater than S at 48 h after intravenous injection of A7. Normal organ uptakes also tended to be increased by AT-II infusion. Further study is needed to get optimum effect of hypertensive treatment on biodistribution of radiolabeled MoAb.

Angiotensin II↗

201Tl and 99Tcm-human serum albumin for assessment of the effect of hypertensive treatment with angiotensin II infusion on tumour circulation.

The biodistribution of 201Tl and of 99Tcm-human serum albumin (99Tcm-HSA) was observed in tumour-bearing mice to investigate if tissue blood circulation could be evaluated in groups of mice infused with angiotensin II at a rate of 0.5 micrograms kg-1 min-1 (L) or 1 microgram kg-1 min-1 (H). Ten minutes after tracer injection, tumour uptake of 201Tl in the angiotensin II infused group showed a 2.20- and a 3.18-fold increase in the L and H groups, respectively, when compared to a group of mice infused with saline (P = 0.0478 and 0.0029, respectively). The effect of angiotensin II infusion on 201Tl uptake was minimal in normal organs. Decreased normal organ uptake of simultaneously injected 99Tcm-HSA in the L and H groups indicated the contraction of normal organ vessels, while increased tumour uptake of the tracer indicated mechanical dilatation of tumour vessels. We conclude that the effect of angiotensin II or other vasoactive agents can be non-invasively assessed by 201Tl and 99Tcm-HSA scintigraphy.

Angiotensin II↗

[Modifications of fractional uptake method for 123I-IMP].

We intended to improve the fractional uptake (FU) method which was developed to quantify cerebral blood flow using 123I-IMP without blood sampling. The quantification of cardiac output (CO) using first-pass data was adapted to FU method while the original FU method used CO which was estimated from the body surface area of patients. Time-radioactivity curves of the lungs and brain were separately obtained by a small-field-of-view gamma camera. In 24 cases, mean cerebral blood flow (mCBF) obtained by the modified FU method showed the better correlation (r = 0.833, P< 0.001) to mCBF measured by the Patlak plot with 99mTc-HMPAO than the original FU method (r=0.667, p<0.01). With these modifications, the reliability of FU method could be improved and the modified FU method might be performed in the other institutions.

Adult↗

[201Tl SPECT for suspected lung cancer in a case of a systemic arterial supply to the lung without sequestration].

201Tl SPECT showed negative result for the presence of a malignant lesion in a 54-year-old male suspected with primary lung cancer on plain x-ray CT. Thin-section contrast x-ray CT and aortography revealed anomalous left lower pulmonary artery arising from the aorta which mimicked a pulmonary mass lesion in the initial study. 201Tl SPECT gave us a clue to the correct diagnosis.

Aorta↗

Targeting cancer micrometastases with monoclonal antibodies: a binding-site barrier.

Monoclonal antibodies penetrate bulky tumors poorly after intravenous administration, in part because of specific binding to the target antigen. Experiments presented here demonstrate an analogous phenomenon in micrometastases; poor antibody penetration, attributable to a "binding-site barrier" phenomenon, can be seen in guinea pig micrometastases as small as 300 microns in diameter. Increasing the dose of antibody can partially overcome this limitation, but at a cost in specificity.

Animals↗

Prominent uptake of Tl-201 by duodenal leiomyosarcoma after exercise myocardial perfusion study.

Thallium-201 SPECT performed preoperatively for the evaluation of myocardial ischemia in a 72-year-old man with duodenal leiomyosarcoma demonstrated prominent focal uptake in the abdomen. Comparing a transaxial slice of SPECT through the abdominal uptake to the CT scan, the uptake was confirmed to be corresponding to the tumor. The tumor was delineated clearly, in good contrast to the surrounding normal intestine, which showed far less Tl-201 uptake than the tumor. In the delayed SPECT performed 3 hours after injection, although the intestinal activity became perceptible, the tumor still could be differentiated from the surrounding normal intestine. In this case, the exercise might be attributable to the initial low Tl-201 uptake by the normal intestine, which might otherwise have been an obstacle to Tl-201 scintigraphy for abdominal tumor detection. This case suggests the use of exercise for avoiding unfavorable intestinal activity, and the possibility of Tl-201 SPECT for abdominal tumor imaging.

Aged↗

Variable portal circulation from inferior mesenteric vein assessed by per-rectal radionuclide administration.

The intrahepatic distribution of radioactivity after the per-rectal administration of 201T-chloride and/or 99Tcm-pertechnetate was investigated in 177 studies in 149 patients with no liver disease or diffuse liver disease and compared with that of 99Tcm-stannous (99Tcm-Sn) colloid scintigrams. The patients were classified into two groups: distribution of intrahepatic radioactivity of 201Tl and/or 99Tcm-pertechnetate scintigrams similar to (homogeneous) or different from (heterogeneous) that of 99Tcm-Sn-colloid scintigrams. The heterogeneous group was divided into three subgroups: increased radioactivity of the right lobe (right dominant pattern), increased radioactivity of the left lobe (left dominant pattern) and uneven distribution of radioactivity in both lobes (uneven pattern). Of the 80 patients in whom the studies were performed in the supine position at rest, 14 (17.5%) showed a heterogeneous pattern (8 right dominant, 4 left dominant, 2 uneven) and 66 (82.5%) a homogeneous pattern. In the 97 patients allowed free body movement, 6 (6.2%) showed a heterogeneous (1 right dominant, 5 left dominant) and 91 (93.8%) a homogeneous pattern. A significant difference in the incidence of heterogeneous distribution between the resting and free body movement groups was found (P < 0.05). One patient with a left dominant pattern after free body movement with 201Tl showed a right dominant pattern at rest in the 99Tcm-pertechnetate study. It is concluded that a heterogeneous intrahepatic distribution of inferior mesenteric vein blood is sometimes observed and that the distribution of portal vein blood flow seems to be affected by the patient's positioning and free body movement.

Administration, Rectal↗

Comparative biodistribution of indium- and yttrium-labeled B3 monoclonal antibody conjugated to either 2-(p-SCN-Bz)-6-methyl-DTPA (1B4M-DTPA) or 2-(p-SCN-Bz)-1,4,7,10-tetraazacyclododecane tetraacetic acid (2B-DOTA).

The biodistribution of indium-111/yttrium-88-labeled B3 monoclonal antibody, a murine IgG1k, was evaluated in non-tumor-bearing mice. B3 was conjugated to either 2-(p-SCN-Bz)-6-methyl-DTPA (1B4M) or 2-(p-SCN-Bz)-1,4,7,10 tetraazacyclododecane tetra-acetic acid (2B-DOTA) and labeled with 111In at 1.4-2.4 mCi/mg and 88Y at 0.1-0.3 mCi/mg. Non-tumor-bearing nude mice were co-injected i.v. with 5-10 microCi/4-10 micrograms of 111In/88Y-labeled B3 conjugates and sacrificed at 6 h and daily up to 168 h post-injection. Mice injected with 111In/88Y-(1B4M)-B3 showed a similar biodistribution of the two radiolabels in all tissues except the bones, where significantly higher accretion of 88Y than 111In was observed, with 2.8% +/- 0.2% vs 1.3% +/- 0.16% ID/g in the femur at 168 h, respectively (P < 0.0001). In contrast, mice receiving the 111In/88Y-(DOTA)-B3 conjugate showed significantly higher accumulation of 111In than 88Y in most tissues, including the bones, with 2.0% +/- 0.1% vs 1.2% +/- 0.09% ID/g in the femur at 168 h, respectively (P < 0.0001). Whereas the ratios of the areas underneath the curve (%ID x h/g) in the blood, liver, kidney and bone were 0.96, 1.12, 1.13, and 0.74 for 111In/88Y-(1B4M)-B3 and 0.84, 1.23, 1.56, and 1.31 for 111In/88Y-(DOTA)-B3, respectively, ratios approximately 1 were observed between 111In-(1B4M)-B3 and 88Y-(DOTA)-B3. In summary, while neither 1B4M nor DOTA was equally stable for 111In and 88Y, the fate of 88Y-(DOTA)-B3 could be closely traced by that of 111In-(1B4M)-B3.

Animals↗

Application of high affinity binding concept to radiolabel avidin with Tc-99m labeled biotin and the effect of pI on biodistribution.

In order to label avidin with Tc-99m, we took advantage of the high affinity binding of biotin to avidin; we radiolabeled a biotin derivative with Tc-99m and then bound this Tc-99m labeled biotin derivative to avidin. For our labeling approach, N epsilon-biotinyl-L-lysine (Biocytin) was reacted with the N-hydroxy-succinimide ester of benzoylmercaptoacetyltriglycine (Bz-MAG3). The resulting Bz-MAG3-Biocytin was labeled with Tc-99m using Tc-99m glucarate as a Tc-99m transchelating agent and mixed with avidin at a 1:1 molar ratio resulting in almost a quantitative labeling yield. Tc-99m-MAG3-Biocytin/Avidin was stable in serum at 37 degrees C with 97 and 95% of the total Tc-99m activity still bound to avidin at 2 and 24 h, respectively. The biodistribution of Tc-99m-MAG3-Biocytin/Avidin in normal Balb/c mice showed a high liver and kidney uptake with 56.6 and 28.9%, respectively at 10 min. We attempted to lower the liver and the kidney activities by reducing the isoelectric point (pI) of avidin by conjugating succinic acid moieties at lysine residues of avidin (pI 10). The kidney uptake decreased to 19.0, 3.1 and 1.7% when the pI of avidin was reduced to 7.0-9.3, 5.5-6.2 and 4.0-4.8, respectively. The lowering of the pI, however, did not change the liver activity appreciably.

Animals↗

[Simple method to estimate cardiac output using first-pass data on RI angiography].

In order to estimate cardiac output (CO) without using data equilibrium state, a simple index (cardiac output index, COI) was developed from the first-pass data as a ratio of the integrated radioactivity on the right ventricle to the total injected radioactivity. COI was well correlated with CO calculated by the conventional Stewart-Hamilton method (r = 0.894, p < 0.01), and thus, CO could be readily estimated from COI. This index might be useful to estimate CO since it can be obtained even with the agents which distribute to organs.

3-Iodobenzylguanidine↗