Biomedical subjects

I Ciftçi

Publications and source records attributed to I Ciftçi.

4 recordsLinked to original sources

PubMed2001

Detection of head and neck cancer with 99Tc(m) glutathione: a correlative study with tissue glutathione and glutathione S-transferase levels.

In this study glutathione (GSH), a natural tripeptide which plays an important role in detoxification reactions, protecting cells against damage from xenobiotics, has been labelled with 99Tc(m) for the demonstration of head and neck cancer. Twenty-eight patients (10 females and 18 males) with various malignancies of the head and neck were given 740 MBq of 99Tc(m)-GSH intravenously and single-photon emission computed tomography (SPECT) images were obtained at 3 h. Semiquantification was performed by drawing regions of interest on three consecutive transaxial slices and tumour to background ratios were calculated. In addition, GSH and glutathione S-transferase (GST) levels were measured in the tumour samples and in normal tissue which were obtained during surgery. Scintigraphic images showed that there was increased uptake in the tumour compared to the normal contralateral side (tumour/normal tissue (mean +/- SD) = 1.94 +/- 0.76). The tissue analyses revealed increased levels of GST in tumour tissues, but both GST and GSH levels in tumour were not statistically different from those in the normal tissue. We conclude that scintigraphic visualization of head and neck tumours can be attributed to increased demand for GSH in cancer. Protein binding might account for the prolonged retention of 99Tc(m)-GSH in the malignant tissue. Like other peptides, it is accumulated and excreted by the kidneys, which allows clear visualization of the abdomen without interference from gastrointestinal system activity.

Adult↗

PubMed2000

Thyroid hemiagenesis.

Thyroid hemiagenesis is a rare congenital anomaly in which one thyroid lobe fails to develop. Tc-99m pertechnetate scintigraphy and ultrasonography can be used to visualize this anomaly. The authors evaluated four cases with Tc-99m pertechnetate scintigraphy and ultrasonography and confirmed thyroid hemiagenesis. In one case, a Tc-99m MIBI scan excluded the suppresssion of the contralateral thyroid lobe. Tc-99m MIBI can be used to confirm the diagnosis of thyroid hemiagenesis.

Adult↗

PubMed2000

Comparison of 99mTc-methoxyisobutyl isonitrile and 201T1 scintigraphy in visualization of suppressed thyroid tissue.

UNLABELLED: Both (201)TI and (99m)Tc-methoxyisobutyl isonitrile (MIBI) have been used in the visualization of suppressed thyroid tissue in patients with autonomously functioning thyroid nodules (AFTNs). It has been suggested that thyroid-stimulating hormone (TSH) control is not a major determinant of both tracers. However, the mechanism of thyroid uptake of these agents is controversial. In this study, we compared (201)TI and MIBI in the visualization of suppressed thyroid tissue in patients with a solitary toxic AFTN. METHODS: Thirty-two patients (13 triiodothyronine [T3] and 19 T3 + levorotatory thyroxine [T4] hyperthyroid patients) with toxic AFTNs visualized on (99m)Tc-pertechnetate scanning were included in the study. All patients underwent MIBI and (201)TI thyroid scintigraphy within a 3-d interval. The scintigrams were analyzed both visually and semiquantitatively. For the semiquantitative analysis, regions of interest (ROIs) were generated over the nodule (N) and contralateral normal lobe (E), and the mean counts in each ROI were calculated. RESULTS: The N/E uptakes (mean +/- SD) for pertechnetate, MIBI, and (201)TI were 11.37 +/- 4.53, 4.76 +/- 1.38, and 1.63 +/- 0.15, respectively, in T3 + T4 hyperthyroid patients and 9.46 +/- 3.64, 2.73 +/- 0.63, and 1.57 +/- 0.23, respectively, in T3 hyperthyroid patients. Our results showed that (201)TI uptake of suppressed thyroid tissue compared with AFTN was more prominent and significantly higher than that of MIBI for both groups of patients (P = 1.08E-05 for T3 and 6.15E-09 for T3 + T4 hyperthyroidism). There was no significant difference for either pertechnetate or (201)TI (P > 0.05) when the N/E uptakes of both groups of patients were compared. However, the N/E uptake of MIBI in T3 + T4 hyperthyroid patients was significantly higher than that in T3 hyperthyroid patients (P = 6.69E-06). CONCLUSION: Clear visualization of suppressed thyroid tissue with both (201)TI and MIBI in patients with low serum concentrations of TSH suggests that TSH is not a major factor in the thyroid uptake of either agent. (201)TI is superior to MIBI in the visualization of suppressed thyroid tissue in patients with a toxic thyroid nodule. An increased rate of metabolism in the follicular cells of AFTNs in T3 + T4 hyperthyroid patients compared with that in T3 hyperthyroid patients might be responsible for the higher N/E for MIBI compared with that for (201)TI.

Adult↗

PubMed1999

The relation between the degree of gastro-oesophageal reflux and the rate of gastric emptying.

In this study, we evaluated the relationship between the degree of gastro-oesophageal reflux and the rate of gastric emptying and determined the variability of gastric emptying in children. The reproducibility of radionuclide imaging for the presence and grading of gastro-oesophageal reflux was also examined. Twenty-eight children less than 2 years of age participated in the study. For assessment of variability, all subjects underwent two scintigraphic studies. For each study, the number of reflux episodes and gastric emptying half-times were recorded. The amount of reflux was graded according to the classification suggested by Blumhagen. Patients with grade 1 reflux were considered low-grade refluxers, while patients with grade 2 or 3 reflux were considered high-grade refluxers. The level of reflux for each patient was based on the highest reflux grade recorded in either study. Of the 28 patients, 19 had reflux in at least one study. Ten patients had high-grade and nine patients low-grade reflux. All patients but one with high-grade reflux had the same grade of reflux in both studies (90%). Of nine patients with low-grade reflux, three had the same grade in both studies. The mean half-time was significantly higher for high-grade than for low-grade refluxers (P < 0.05). For subjects with low-grade reflux, this value did not differ significantly from that of non-refluxers (P > 0.05). Our results show that patients with high-grade gastro-oesophageal reflux had prolonged gastric emptying. The inter- and intra-subject variability of gastric emptying in children appeared to be low. Reproducibility for the presence and grading of gastro-oesophageal reflux by the radionuclide method was good, with the highest value being for the diagnosis of high-grade gastro-oesophageal reflux.

Gastric Emptying↗