Biomedical subjects

A Iio

Publications and source records attributed to A Iio.

At least 19 recordsLinked to original sources

PubMed1992

[A case with delayed-onset radiation pneumonitis suspected to be induced by oral etoposide].

Radiation pneumonitis usually occurs within 1-3 months after the completion of radiation therapy. A 63-year-old male with primary lung cancer treated by radiation therapy developed radiation pneumonitis 5 months after the completion of radiation therapy. He received 60 Gy to the lung tumor in a conventional fractionation schedule, and then two courses of intravenous chemotherapy using cis-diamine-dichloroplatinum (II) (110-140 mg) and etoposide (140-175 mg). Oral etoposide was initiated for bone metastases on the 104th day after the completion of radiation therapy at a daily dose of 20 mg, to a total dose of 1075 mg. He complained of fever and exertional dyspnea 5 months after the completion of radiation therapy. Chest radiography showed homogeneous infiltrates in the irradiated lung. These clinical signs and symptoms were refractory to antibiotic therapy, but steroid therapy resulted in marked improvement. The development of radiation pneumonitis was suspected to be induced by oral etoposide, which was given before the onset of radiation pneumonitis. These data suggest that etoposide induces a recall phenomenon, as has been demonstrated with such drugs as adriamycin and actinomycin-D.

Administration, Oral↗

PubMed1992

[Temperature distribution and geometry of the electrodes in RF interstitial hyperthermia using circular and interstitial electrodes].

To evaluate the feasibility of clinical application of a newly developed interstitial hyperthermia system, which consists of an 8 MHz radiofrequency generator, interstitial needle electrodes, and a superficial circular electrode, we conducted preclinical experiments using an agar phantom and VX-2 carcinoma in the rabbit. In the experiment with an agar phantom, four 4 cm needle electrodes were placed in a square array at intervals of 1.0, 1.5, and 2.0 cm. Thermography demonstrated homogeneous temperature distribution at electrode intervals of 1.0 and 1.5 cm, but hot spots around the electrodes at an interval of 2.0 cm. When electrode deviation was less than 8 degrees from the parallel plane, no temperature deviation was observed. Using two 2 cm electrodes and two 4 cm electrodes in square array, thermography demonstrated a homogeneous temperature distribution in the area surrounded by the electrodes. Even if the electrodes were located at the periphery of the agar phantom, a homogeneous temperature distribution was obtained in the area surrounded by the electrodes. Using four 4 cm electrodes at intervals of 1.5 cm in VX-2 carcinoma in the rabbit, ideal heating was obtained: 42 degrees C at the periphery of the tumor and 43 degrees C at the center. These data suggest that the newly developed interstitial hyperthermia apparatus provides homogeneous heat distribution at electrode intervals of 1.5 cm or less and can be used in a Phase I study for deep-seated or superficial tumors.

Animals↗

PubMed1992

Isolation and characterization of a chicken tyrosinase cDNA.

Complementary DNA clones coding for chicken tyrosinase were isolated from retinal pigmented epithelium of chicken embryo. Sequence analysis shows that one of the cDNA clones consisting of 1,997 nucleotides has an open reading frame coding for 529 amino acids. The deduced protein has nine N-glycosylation sites and a transmembrane region. A sequence comparison of the deduced chicken tyrosinase with the mouse and human homologues revealed that amino acid sequences are conserved for the entire polypeptides. Seventy-two percent and 73% of amino acids in the chicken sequence are identical to that of the mouse and human tyrosinases, respectively. Histidines neighboring the postulated copper-binding sites and the cysteines are well conserved. RNA blotting analysis showed that a major transcript of 2.5 kb is detected in retinal pigmented epithelium of a 9-day-old chicken embryo.

Amino Acid Sequence↗

PubMed1991

[Detection of common bile duct stones by hepatobiliary scintigraphy].

Hepatobiliary scintigraphy and direct X-ray cholangiography were compared in 29 patients with common bile duct (CBD) stones confirmed at surgery. The scintigraphic findings included no visualization of the biliary system (NV), pooling of bile in the biliary system (PB), prolonged transit time over 60 min (PTT), filling defect in the CBD image (FD), and reflux of bile toward the intrahepatic ducts after gallbladder stimulation (RB). The positive rates of NV, PB, PTT, FD, and RB in patients with CBD stones were 7%, 31%, 17%, 48%, and 14%, respectively. One or more of these five findings was found in 83%. Although the NV was a useful finding suggesting complete obstruction of the CBD, it shared little in the diagnosis of CBD stone. The positive rate of the PB was relatively high and it would be a useful finding as an indication of the presence of passage disturbance of the CBD. The PB was usually accompanied by the FD. The PTT had some usefulness in the detection of incomplete obstruction of the CBD in patients with a visualized gallbladder. In patients with no visualization of the gallbladder, however, the transit time tended to be shorter than that of gallbladder visualized patients. Therefore, the judgment of PTT in patients with no visualized gallbladder needed another criteria. The FD was the most frequent among the five findings and the sites of FD correlated well with CBD stones on direct X-ray cholangiography. The FD would be a reliable finding indicating CBD stone or CBD stenosis. Although the RB was a finding limited in patients with a visualized gallbladder, it seemed to be a helpful findings for the detection of CBD stone in patients with a mildly dilated CBD.

Adult↗

PubMed1991

ECG-gated thallium-201 myocardial SPECT in patients with old myocardial infarction compared with ECG-gated blood pool SPECT.

We evaluated one of the merits of ECG-gated thallium-201 single photon emission computed tomography (g-T1 SPECT), i.e., the ability to appreciate left ventricular (LV) wall motion. LV wall motion assessed by g-T1 SPECT and by ECG-gated Blood Pool SPECT (g-BP SPECT) was classified into three grades and compared segment by segment. T1-201 uptake by g-T1 SPECT was also classified into three grades and compared with those of wall motion in g-BP SPECT. Fifty patients with prior myocardial infarction were injected intravenously at rest with 111 to 185 M Bq (3 to 5 mCi) of Tl-201. The left ventricular regions were divided into anterior, septal, inferior and lateral segments (50 patients X 4 segments = 200 segments in total). The grades of wall motion and Tl-201 uptake detected by g-Tl SPECT correlated well with those of wall motion in g-BP SPECT (94.5% and 85%, respectively). With g-Tl SPECT it was possible to evaluate left ventricular wall motion, providing clear perfusion images.

Adult↗

PubMed1990

[The role of gallium-67 citrate scintigraphy in gastro-intestinal malignant lymphoma].

To evaluate the clinical usefulness of gallium-67 scintigraphy in the detection of the gastrointestinal (GI) non-Hodgkin's lymphoma (NHL) and in the assessment of the therapeutic effects, gallium-67 scintigraphy was reviewed on 24 cases (25 lesions; stomach in 20, ileum in 2, and terminal ileum and/or cecum in 3). Twenty-three out of the 25 lesions (92.0%) were detected by gallium-67 scintigraphy, while barium study could detect all of the 25 lesions. The sizes of the gallium-67 negative 2 lesions were the smallest of all (2.5 and 3.0 cm). The tumor size was considered to the most important factor in the detection by gallium-67 scintigraphy, while the histological classification and the location of the tumor were not related to its detectability. Findings in follow-up gallium-67 scintigraphy after therapy on 10 cases were correlated well with the therapeutic effects. These data suggest that gallium-67 scintigraphy is useful for the detection of GI involvement of NHL and for the assessment of therapeutic effects.

Adult↗

PubMed1990

The role of gallium 67 imaging in non-Hodgkin's lymphoma of the gastrointestinal tract.

To evaluate the clinical usefulness of gallium 67 imaging in the detection of gastrointestinal (GI) non-Hodgkin's lymphoma (NHL) and in the assessment of the therapeutic effects, images were reviewed in 24 cases (25 lesions: stomach, 20; ileum, 2; and terminal ileum and or cecum, 3) and were compared using barium studies and, in 16 cases, computerized tomography (CT). In all, 23 (92.0%) of the 25 lesions were detected by 67Ga citrate imaging, the barium studies detected all 25, and CT detected 15 of 16 lesions (93.8%). The two lesions not identified by imaging and the one not found by CT were the smallest of all. In 2 (8.7%) of the 23 lesions positively identified by 67Ga-citrate imaging, both CT and imaging revealed the extent of the tumor more accurately than did the barium studies. In all but one of the patients, a close correlation existed between the imaging results and the therapeutic effects. These data suggest that 67Ga imaging is useful in conjunction with CT and barium studies for the detection of GI NHL and for the assessment of both the spatial extent of disease and the therapeutic effects, although a lack of 67Ga uptake after therapy does not always indicate a good therapeutic effect.

Barium Sulfate↗

PubMed1990

Single photon emission computed tomography (SPECT) using N-isopropyl-p-(123I) iodoamphetamine (IMP) in the evaluation of patients with epileptic seizures.

To evaluate the clinical usefulness of IMP SPECT in the diagnosis of epilepsy, 6 normals and 52 patients in the interictal phase were studied. Thirty min after an intravenous injection of 111 MBq IMP, SPECT was performed using a rotating gamma camera. Of 21 patients with simple partial seizures, a localized decrease of uptake was shown in 16, and an increase in 3. Topologically, these findings corresponded well to the ictal symptoms. Nine of 13 patients with localized epileptic EEG had a good correspondence between the findings on EEG and IMP SPECT. In 20 of 23 with complex partial seizures, the coronal images showed laterality of uptake in the temporal lobes, whereas the CT was normal in 14. However, these findings on IMP SPECT agreed with the EEG in the temporal leads in only 5 cases. Of 8 patients with primary generalized seizures, a diffuse cerebral decrease was shown in 3 of 4 patients with convulsive seizures (grand mal), and a normal uptake in 3 of 4 patients with non-convulsive seizures (petit mal). However, 2 patients showed a localized decrease, therefore, we determined that they suffered from partial seizures evolving to secondarily generalization. From these data, we concluded that IMP SPECT could be a useful method in the diagnosis of epilepsy.

Adolescent↗

PubMed1990

Serum CA125 level is a good prognostic indicator in lung cancer.

The serum CA125 level was determined by a one-step immunoradiometric assay method in patients with lung cancer. Increased serum CA125 levels were observed in 37.8% of patients with squamous cell cancer, in 30.0% of those with adenocarcinoma and in 60.0% of those with small call cancer. Most patients with increased serum CA125 levels were in stages 3 or 4. Patients with pleural effusions or ascites showed high serum CA125 levels. The survival time was significantly shorter in patients with increased serum CA125 levels than in those within normal limits. Among patients with advanced disease (stages 3 and 4), an increased serum CA125 level was again a poor prognostic factor (P less than 0.01). The existence of a pleural effusion did not correlate with the survival time. We conclude that CA125 is a good indicator of disease extent and serum levels correlate to the length of survival.

Adult↗

PubMed1990

Serum albumin metabolism in rheumatic diseases: relationship to corticosteroids and peptic ulcer.

Serum albumin concentrations and albumin metabolism were assessed in 150 patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and healthy subjects. Hypoalbuminemia was more marked in RA patients than in SLE patients. There was no correlation in RA patients between albumin levels and either disease activity or glucocorticosteroid administration; however, hypoalbuminemia in RA patients significantly correlated with juxta-articular erosions or with the incidence of peptic ulcer. The incidence of peptic ulcer was higher in RA patients with the combination of hypoalbuminemia and corticoid therapy, and reduced by the injection of anabolic steroid. In contrast, anabolic steroid did not improve hypoalbuminemia and bony erosions in the patients. The fractional catabolic rate of albumin was similarly elevated in both RA and SLE, while the absolute catabolic rate was increased to a greater extent in SLE patients. This explains the differences in serum albumin concentration between the patients with RA and SLE.

Adolescent↗

PubMed1990

Diffuse gallium-67 uptake in radiation pneumonitis.

To evaluate the clinical usefulness of Ga-67 imaging for the assessment of radiation pneumonitis, 12 patients who had developed radiation pneumonitis after receiving radiotherapy alone for non-small-cell lung cancer from 1979 through 1988 were reviewed. Diffuse bilateral Ga-67 uptake occurred in 5 out of the 12 cases; in the other 7 cases, Ga-67 uptake was confined to the irradiation lung. Conversely, chest radiography showed infiltrates only in the irradiated lung. Histopathology of the lung in four out of the five cases that showed diffuse Ga-67 uptake in the lung, however, revealed that the lung outside the radiation field with Ga-67 uptake was consistent with interstitial pneumonitis induced by radiation. These results suggest that radiation pneumonitis could extend beyond the irradiated lung and that Ga-67 imaging is more useful than chest radiography for the assessment of the spatial extent of radiography pneumonitis.

Aged↗

PubMed1989

[Radiation-induced esophageal stricture in patients with non-small cell lung cancer treated with chemoradiotherapy].

Five out of 165 cases (3.0%) which were treated for non-small cell lung cancer with radiotherapy (98 cases were treated with chemoradiotherapy, and the other 67 cases, radiotherapy alone) developed esophageal stricture. Their clinical courses, the relationship among radiation dosage, combination with chemotherapy, the length of the irradiated esophagus, and the occurrence of esophageal stricture were reviewed. One of the 5 cases was a case with lung cancer in Bloom's syndrome, which developed an esophageal stricture after receiving only 30.6 Gy (the TDF value was 46.2) to the esophagus. This case suggests the possibility that a patient with Bloom's syndrome is more radiosensitive than normal controls. The other 4 cases were treated with combined chemoradiotherapy. One of the 4 cases was treated with concomitant use of bleomycin (BLM), while the TDF value was not more than 100 (75.4). The concomitant sue of BLM was almost certainly the cause of the esophageal stricture. The other 3 cases were treated with chemoradiotherapy, the TDF values of which were more than 100 (108.7, 112.5, and 129.3). The chemotherapy combined with radiotherapy and the overdosage were considered to be the cause of the esophageal stricture in these 3 cases. These data suggest that in Bloom's syndrome, radiotherapy should be performed carefully and that BLM should not be used simultaneously with irradiation to the esophagus. It is also believed that a radiation dose over 100 in TDF value to the esophagus should be discouraged when chemotherapy is combined.

Adult↗

PubMed1989

[Single photon emission computed tomography (SPECT) with N-isopropyl-p-(123I) iodoamphetamine in partial epilepsy--evaluation of delayed image].

Thirty eight patients with partial seizures in the interictal phase were studied using single photon emission computed tomography performed 30 min. (early image) and 4-4.5 hrs. (delayed image) after an injection of 111 MBq (3 mCi) N-isopropyl-p(123I) iodoamphetamine (IMP). Five types of distribution changes were observed on IMP-SPECT between the early and delayed images. Eight patients, Type 1, exhibited an unchanged distribution of IMP between the early and delayed images. Fifteen patients, Type 2, showed a smaller area of low uptake on the IMP-SPECT (delayed image) compared to that on the IMP-SPECT (early image)-redistribution. The Type 3 patients exhibited an initial uptake area on the IMP-SPECT (early image) which later became a lower uptake area on the IMP-SPECT (delayed image)-reversed redistribution. This type was further classified into three categories according to the initial uptake pattern including (a) Type 3A, 3 patients with increased uptake area, (b) Type 3B, 6 patients with normal uptake area, and (c) Type 3C, 6 patients with decreased uptake area. With Type 2, the epileptic findings on the present interictal electroencephalography (EEG) were shown in 11 of 15 patients. However, we could not find any other remarkable correlation among these 5 types and the clinical factors (the types of seizures, the X-CT findings, the present interictal EEG data, the present frequency of seizures, and the intervals from the last seizure). In 2 patients with Type 3B who suffered from simple partial seizures, a region of the normal distribution on the IMP-SPECT (early image) became a lower uptake area on the IMP-SPECT (delayed image), corresponding topologically to the ictal symptoms. In this experience, we determined that the IMP-SPECT (delayed image) could be useful in patients with the epileptic lesions unable to be detected on the IMP-SPECT (early image).

Adolescent↗

PubMed1989

[Diagnostic value of the reflux sign in cholescintigraphy after administration of a gallbladder contracting agent--a comparison with X-ray cholangiography].

This study reviewed 25 patients with the reflux sign in cholescintigraphy to assess its diagnostic value in evaluating biliary passage. After at least 4-hour fasting 5 mCi of 99mTcPMT or p-butyl IDA was injected intravenously and serial images were recorded before and after intramuscular injection of 10 micrograms of ceruletide diethylamine (caerulein). The reflux sign was determined positive when increased radioactivities in the left hepatic duct (minor reflux; MIR) or more peripheral intrahepatic ducts (major reflux; MAR) were recognized after injection of caerulein. The reflux sign was found in 28 of 237 (12%) studies. Direct and/or indirect X-ray cholangiograms were available in 25 (MIR; 15, MAR; 10). They included common bile duct (CBD) stone in 4, dilated CBD in 4, biliary dyskinesia (BD) in 4, chronic pancreatitis (CP) in 4, gallbladder (GB) stone in 3, duodenal ulcer (DU) in 2, CBD adenoma, pancreatic pseudocyst (PP), duodenal diverticle (DD), and acute cholangitis (AC) in 1 each. Their serum bilirubin levels were within normal limit in all but 2 at the time of cholescintigraphy. Transit time of radionuclides to the duodenum was found prolonged more than 60 min in 17 (68%) patients and persistent pooling in the CBD was found in 8 (28%) patients on scintigrams. The diameter of the CBD on X-ray cholangiogram was ranged 4 to 17 mm. Dilated CBD of more than 10 mm was found in 13 (52%) patients and apparent stenosis of the CBD in 6 (24%) patients. MAR seemed to correspond to increased diameter of the common hepatic more than 2 mm after caerulein injection in DIC. No abnormal findings in X-ray cholangiography was found in 10 (40%) patients including 3 with BD, 2 with GB stone, 2 with DU, 1 each with CP, PP, and AC. All those patients demonstrated MIR. We concluded that major reflux (MAR) sign was helpful in detecting an incomplete obstruction of the CBD, especially in patients with slightly to mildly dilated CBD.

Adult↗

PubMed1989

SPECT volume measurement using an automatic threshold selection method combined with a V filter.

The volume measurement of various organs by single photon emission computed tomography (SPECT) has generally been performed by summing up the voxels lying within the outer edge of the organ determined by thresholding as a function of the maximum reconstructed counts within a volume of interest. The optimum threshold level, however, is influenced by various factors. To eliminate this problem, Mortelmans et al. (1986) proposed to use an automatic threshold selection method (ATSM) based on discriminant criteria and to correct the errors induced by the imperfect system response using the method based on linear regression analysis, which has some problems in practical application. We tried to use ATSM combined with a V filter. The correlation coefficient (r) and the regression equation between the true (x) and the calculated volume (y) obtained by experimentation using 22 phantoms with a volume ranging between 26 ml and 380 ml were as follows: r = 0.994 and y(ml) = 1.015 x +1.09 using ATSM combined with a V filter, while r = 0.993 and y(ml) = 1.110 x +30.55 using only ATSM. The relative error between the true and the calculated volumes decreased significantly (P less than 0.01) from 37.7% +/- 26.9% to 5.5% +/- 4.2%. The results suggest that ATSM combined with a V filter is useful for correcting the errors caused by an imperfect system response, and is available and reliable for SPECT volume determination even when the organ volume is small.

Filtration↗

PubMed1989

A unified computer program for assessment of attenuation correction and data acquisition methods in single photon emission computed tomography (SPECT).

A computer based simulation program was developed to assess the usefulness of various attenuation correction algorithms and data acquisition methods in single photon emission computed tomography (SPECT) in a unified approach. The program analytically calculated projection ray sums from a mathematical model with various distributions of activities and either uniform or non uniform attenuation coefficients by using the line integrals including the effect of attenuation. Data acquisition starting at arbitrary angles, various acquisition angles, including a 180 degree scan and a non circular orbit of a gamma camera, including an elliptical orbit can readily be taken into consideration in our simulation program. To simulate non circular orbit data acquisition, the resolution dependence on the object distance from the collimator surface was incorporated into the simulation. This computer based simulation program allows various combinations of attenuation correction algorithms such as hybrid methods, and data acquisition methods can be evaluated under a large number of study conditions. The usefulness of this computer based simulation program is shown with several representative examples.

Algorithms↗

PubMed1989

Assessment of hepatic excretory function in chronic liver disease by hepatobiliary scintigraphy.

Hepatobiliary scintigraphy was performed in 23 normal subjects and 47 patients with chronic liver disease (chronic hepatitis; n = 27, liver cirrhosis; n = 20) to evaluate its availability as a test of liver function. After intravenous administration of Tc-99m N-pyridoxyl-5-methyl-tryptophan, the data were acquired for 60 min and the time-activity curves of ROIs (the heart and liver) were generated. In two compartment model simulation, the early blood clearance rate (kl), late blood clearance rate (km), hepatic uptake rate (ku) hepatic excretion rate (ke), and hepatic excretion T 1/2 were calculated. There was no significant difference in those four k values in normal and chronic hepatitis. However, in liver cirrhosis each of them, except km, was lower than in normal subjects. The kl value correlated closely with the indocyanine green plasma clearance test, whereas the ke and T 1/2 values were closely correlated with the level of serum bilirubins. Only hepatobiliary scintigraphy showed the excretory function of the liver quantitatively and the ke value was helpful in detecting hepatic excretory dysfunction early in chronic liver disease before serum bilirubins increased.

Adolescent↗

PubMed1989

A unified design algorithm of two-dimensional digital filters for radioisotope image processing.

A unified design algorithm of two-dimensional digital filters for radioisotope image processing based on the Fourier-Bessel transform and the weighted least-squares method is described. The algorithm presented here can treat the various kinds of two-dimensional digital filters in a unified approach. Design examples are presented and several graphs are included to show the relationships between the design parameters as an aid in practical applications. The application of the method in radioisotope image processing is also presented. Several low-pass, Wiener and band-pass filters were designed using the method and applied to some clinical data in nuclear medicine including SPECT images. The digital filter design technique proposed here is considered to provide a powerful tool for extraction of additional qualitative information and improvement of the quality of nuclear medicine images both in research and in routine clinical work.

Algorithms↗