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C Reiners

Publications and source records attributed to C Reiners.

At least 73 records · Page 4Linked to original sources
PubMed1998

Reverse transcriptase-polymerase chain reaction analysis of thyrocyte-relevant genes in fine-needle aspiration biopsies of the human thyroid.

Currently, fine-needle aspiration cytology is a valuable tool in the routine diagnosis of suspicious thyroid nodules. We present a very sensitive method for the molecular analysis of the expression of several genes important for normal thyroid function in parallel to the cytological diagnosis. We adapted reverse transcriptase polymerase chain reaction (RT-PCR) to amplify thyroid-typical mRNAs in samples of thyroid carcinoma cells as small as those obtained by fine-needle aspiration biopsy (FNAB), ie, 100-1000 cells, and applied this procedure to four routinely taken FNABs. Gene products such as thyroglobulin (Tg), thyroid-stimulating hormone-receptor (TSHr), sodium/iodide-symporter (NIS), type I iodothyronine-5'-deiodinase (DI), and type II iodothyronine-5'-deiodinase (DII) were analyzed. To establish RT-PCR protocols, serial dilutions of follicular thyroid carcinoma cells, FTC-133, which express these genes at low levels, were initially used for RNA isolation. Successful RNA isolation and reverse transcription were checked by the amplification of beta-actin mRNA. We detected the mRNAs coding for Tg in as little as 10 cells, for NIS in 100 cells, and for TSHr, DI, and DII in 10,000 cells. After preparing cytological smears of four routinely taken FNABs, all above-mentioned thyroid-typical mRNAs were observed by using the material remaining in the needle for RNA isolation followed by RT-PCR. This method offers the possibility of obtaining two different types of information from the same routinely taken thyroid FNAB: the cytological diagnosis and the expression pattern of several diagnostically relevant genes. Therefore, a more specific diagnosis could be rendered in the preoperative state, and may lead to more specific therapy.

Biopsy, Needle↗
PubMed1998

Influences on evaluability of radionuclide ventriculography in chemotherapy patients.

Radionuclide ventriculography (RNV) is an established method of evaluating cardiotoxic side-effects of chemotherapy. The image quality of RNV depends on labelling yields obtained after red blood cell (RBC) labelling with 99Tc(m)-pertechnetate and has an influence on the evaluation of the left ventricular ejection fraction (LVEF). Several drugs and certain parameters of RBC labelling are known to have a detrimental effect on the labelling yield, but often the reason for poor image quality remains unclear. The aim of this study was to determine the effect of chemotherapeutic agents on LVEF evaluation. The chemotherapeutic medications and RNV data of 116 patients were noted. The patients underwent 205 RNV examinations (up to 7 RNV follow-up examinations) consisting of rest and stress studies. Ten patients with a poor labelling yield after in vivo labelling received an additional RNV study after in vitro labelling. The effects of commonly used anticoagulants and chemotherapeutic drugs on labelling yields were also investigated in experiments on in vitro RBC labelling. In vitro labelling had the advantage of better detection of pathological alterations in left ventricular motility, but often improved evaluability only slightly. The administration of corticosteroids showed an unexpected positive correlation with image quality (Spearman correlation coefficient: prednisone, 0.42403, P = 0.0013; prednisolone, 0.45629, P = 0.0286) and labelling yield (prednisolone, 0.65466, P = 0.0024), whereas idarubicin showed a negative correlation with image quality (-0.53364, P = 0.005). A slight positive correlation of prednisolone with LVEF at rest (0.45425, P = 0.0197) was also noted. Using our evaluation software, the manual contour method was found to be superior to the automatic determination of the left ventricular contour. Cycle ergometry alone caused a significant deterioration in image quality. The in vitro results suggested a negative influence of epirubicine on labelling yields at very high concentrations (10(-3) M). Our main result was that a clinically adequate study is possible in patients with moderate image quality and labelling yields. Furthermore, the administration of corticosteroids had a positive impact on image quality.

Adult↗
PubMed1998

[123I]beta-CIT SPECT visualizes dopamine transporter loss in de novo parkinsonian patients.

Parkinson's disease (PD) is characterized by degeneration of dopaminergic neurons in the basal ganglia, which may be visualized by single photon emission computed tomography (SPECT) in combination with the cocaine analog methyl-3-beta-(4-beta[123I]iodophenyl)tropane-2beta-carboxylate ([123I]beta-CIT). The aim of our study was to correlate findings of SPECT with clinical data of 34 previously untreated, idiopathic parkinsonian patients [age: 59.58+/-10.03 (mean+/-SD) years; Hoehn and Yahr Scale (HYS) mean range: 1.97+/-0.83, ranges I-III; Unified PD Rating Scale 3.0 (UPDRS, 30.64+/-18.68) and 15 healthy controls (age 47.93+/-10.47 years). SPECT scans were performed with a single-head gamma-camera 24 h after intravenous injection of [123I]beta-CIT. Comparison of the striatum/cerebellum (S/C) ratio of [123I]beta-CIT uptake of controls and parkinsonian subjects, subdivided according to their HYS range, was significant. No influence of age or sex was observed. Significant correlations were found between scores of the HYS, UPDRS parts I-III, part II, part III, and the S/C ratio of [123I]-CIT uptake. Moreover, SPECT with the radiotracer [123I]beta-CIT revealed side-to-side differences in parkinsonian patients and significant associations to contralateral clinical extrapyramidal symptomatology. Our data show that SPECT with [123I]beta-CIT is a valuable tool for estimating disease severity in PD.

Adult↗
PubMed1998

Rapid urinary iodide test.

Assessment of iodine deficiency and monitoring of iodine supplementation programs demand rapid, simple, and cost-effective methods for the determination of urinary iodide concentrations. We propose a semiquantitative rapid test, based on the iodide-catalyzed oxidation of 3,3',5,5'-tetramethylbenzidine by peracetic acid/H2O2, to yield colored products. The color of the chemical reaction is compared with color categories of a pictogram corresponding to three ranges: <100, 100-300, and >300 microg/L (<0.79, 0.79-2.36, and >2.36 micromol/L) of iodide concentrations. The test is very easy to perform and does not require any instrumentation or apparatus. Sample preparation is simple and consists of the removal of interfering substances by disposable columns, 65 x 10.5 mm, packed with purified activated charcoal. For comparison with a reference method for measuring urinary iodide, by high-performance liquid chromatography, we determined the iodide concentrations of 370 random (untimed) urine samples from consecutive patients by both high-performance liquid chromatography and the rapid test. The results obtained by both methods are in close agreement, with respect to classification of the samples according to the above three ranges, with a maximum difference of less than 5% for each range. Median (y) values of a given distribution of urinary iodide concentrations can be calculated from the percent (x) of samples below 100 microg/L (0.79 micromol/L) using the regression equation: y = 179.78 - 1.60x. This rapid test, therefore, is suited to epidemiological surveys of iodine deficiency, especially in developing countries.

Chromatography, High Pressure Liquid↗
PubMed1998

Effect of small doses of iodine on thyroid function in patients with Hashimoto's thyroiditis residing in an area of mild iodine deficiency.

OBJECTIVE: Several studies have suggested that iodine may influence thyroid hormone status, and perhaps antibody production, in patients with autoimmune thyroid disease. To date, studies have been carried out using large amounts of iodine. Therefore, we evaluated the effect of small doses of iodine on thyroid function and thyroid antibody levels in euthyroid patients with Hashimoto's thyroiditis who were living in an area of mild dietary iodine deficiency. METHODS: Forty patients who tested positive for anti-thyroid (TPO) antibodies or with a moderate to severe hypoechogenic pattern on ultrasound received 250 microg potassium iodide daily for 4 months (range 2-13 months). An additional 43 patients positive for TPO antibodies or with hypoechogenicity on ultrasound served as a control group. All patients were TBII negative. RESULTS: Seven patients in the iodine-treated group developed subclinical hypothyroidism and one patient became hypothyroid. Three of the seven who were subclinically hypothyroid became euthyroid again when iodine treatment was stopped. One patient developed hyperthyroidism with a concomitant increase in TBII titre to 17 U/l, but after iodine withdrawal this patient became euthyroid again. Only one patient in the control group developed subclinical hypothyroidism during the same time period. All nine patients who developed thyroid dysfunction had reduced echogenicity on ultrasound. Four of the eight patients who developed subclinical hypothyroidism had TSH concentrations greater than 3 mU/l. In 32 patients in the iodine-treated group and 42 in the control group, no significant changes in thyroid function, antibody titres or thyroid volume were observed. CONCLUSIONS: Small amounts of supplementary iodine (250 microg) cause slight but significant changes in thyroid hormone function in predisposed individuals.

Adult↗
PubMed1998

[Measurement of incorporation in family members of radioiodine therapy patients after therapy of benign thyroid diseases].

AIM: Patients exhale I-131 after radioiodine therapy. In this study we quantify the amount of radioactivity and resulting thyroid doses found in people living in close contact to patients treated with I-131 after their release from a therapy ward. METHODS: For 31 relatives of 25 patients treated with I-131 the incorporation was monitored using the thyroid probe of a whole body counter. These values are used for a determination of thyroid doses. RESULTS: 11 of the 31 monitored persons had a thyroid activity of less than the minimal detectable activity of 13 Bq. The mean value of the remaining 20 people was 104 Bq in the thyroid resulting in a mean thyroid dose of 0.2 mSv (Maximum: 2 mSv). CONCLUSION: The intake of I-131 for persons in close contact to patients after dismissal from a therapy ward is low. In no case an effective dose exceeding 1 mSv was observed.

Adolescent↗
PubMed1998

Reproducibility of technetium-99m-MAG3 clearance using the Bubeck method.

UNLABELLED: The objective of this study was to estimate the reproducibility of 99mTc-mercaptoacetyltriglycine (99mTc-MAG3) clearance calculated using a single-sample method. METHODS: One hundred forty-seven patients with urological or ear, nose and throat cancer were analyzed in a retrospective study. Each patient had at least two clearance studies with 99mTc-MAG3 before chemotherapy treatments to monitor renal function. Up to five clearance studies per patient were considered. The reproducibility was estimated by comparing two consecutive investigations. Pairs of investigations with a change in split renal function of more than 5% or an interval of more than 50 days were excluded. Clearance was determined using the Bubeck method. For each pair of consecutive clearance data, the difference between the first and the second measurements was expressed as a percentage of the mean value of the two measurements. The mean of these normalized differences represents the systematic deviation, and the s.d. represents the reproducibility of the compared clearances. RESULTS: After the selection, 242 pairs of consecutive clearance data remained for comparison. Significantly different clearances were observed only between investigations 0 and 1 and between 4 and 5. The systematic deviation of these comparisons totaled -3.8% and -5.7%, respectively. In the other comparisons, no significant deviation induced by the chemotherapy was found. The reproducibility calculated for all comparisons totaled 11.7%. CONCLUSION: The error of reproducibility of 99mTc-MAG3 clearance using the Bubeck method was < or =11.7%. This was an acceptable value, taking into account the greater fluctuation of tubular function compared with the glomerular filtration rate.

Humans↗
PubMed1997

Characteristics of differentiated thyroid carcinoma in children and adolescents with respect to age, gender, and histology.

BACKGROUND: Because of its rarity there have been only a few detailed studies on differentiated thyroid carcinoma (DTC) in children. The current investigation was undertaken to assess the characteristics of DTC with respect to age, gender, and histology in children and adolescents. METHODS: In a questionnaire-based survey, data from 114 children and adolescents with DTC (age range, 3-18 years) was collected from 65 clinical institutions in Germany. Characteristics of 80 females and 34 males were evaluated and the influence of age, gender, histology, multicentric growth, tumor stage, and lymph node involvement on distant metastases was tested using multivariate discriminant analysis. Comparison between groups was performed using the Student's t test and chi-square test. Correlation between incidence and age was assessed by linear regression analysis. RESULTS: The overall incidence of thyroid carcinoma in females was higher than in males, with a peak of female/male ratio occurring at puberty. The incidence of DTC correlated with age in females < 16 years (correlation coefficient [r] = 0.84; P = 0.0006), which was more pronounced in children with papillary thyroid carcinoma (PTC) (r = 0.83; P = 0.006) but not in those with follicular thyroid carcinoma (FTC) (r = 0.20; P = 0.16). FTC was associated with less advanced disease (P = 0.009), fewer lymph nodes involved (P = 0.007), and fewer metastases (P = 0.02) compared with PTC. Males tended to have a higher risk for distant metastases. However, statistical analysis failed to reach a level of significance (P = 0.08). Multivariate analysis revealed tumor stage as the only powerful factor (P = 0.02) correlated with distant metastasis. CONCLUSIONS: The incidence of PTC shows a marked increase in females with the highest female/male ratio occurring at puberty. Childhood thyroid carcinoma frequently is associated with lymph node involvement, distant metastases, and extrathyroidal tumor infiltration. In children FTC appears to be less aggressive than PTC. Advanced local-regional extension stage appears to be the most powerful factor influencing the risk for distant metastases in children.

Adenocarcinoma, Follicular↗
PubMed1997

Polymorphisms in the p53 gene in thyroid tumours and blood samples of children from areas in Belarus.

We present changes in the p53 gene in a group of 70 thyroid tumours and 40 blood samples obtained from children from Belarus. Three thyroid tumours show a polymorphism in exon 6 (codon 213) and 5 tumours show a polymorphism in intron 6, 37 bp upstream to the 5'-end of exon 7. Only one patient has a mutation in exon 7 (codon 258) resulting in an amino acid substitution in the protein p53. The distribution of polymorphisms in the 40 blood samples was as follows: three patients had a polymorphism in exon 6 and two persons had a polymorphism in intron 6. One polymorphism in intron 6 was also found in the group of 30 healthy children from Belarus. The fact that the differences in the sequence in p53 found in the tumours was also seen in the blood of these patients demonstrates that they are polymorphisms not induced by radiation exposure. It is difficult to conclude, if the polymorphisms found by us could be associated with the predisposition to radiation-induced cancer.

Adolescent↗
PubMed1997

Comparison of transcranial sonography, magnetic resonance imaging, and single photon emission computed tomography findings in idiopathic spasmodic torticollis.

Various lines of evidence suggest that the basal ganglia and thalamus are involved in the pathogenesis of idiopathic dystonia, but unfortunately neuroradiological and pathological data are sparse and controversial. In this study, we have examined 10 patients with spasmodic torticollis by neuroimaging techniques, including transcranial sonography (TS; n = 10), conventional (n = 10) and diffusion-weighted (n = 5) magnetic resonance imaging (MRI), and single photon emission computed tomography (SPECT; n = 10), employing [123I]iodobenzamide (IBZM) as a ligand with a high affinity to the D2 receptor. In seven patients, TS showed small hyperechogenic lesions in the medial segments of the lentiform nucleus contralateral to the side of head deviation. In accordance with the site of TS abnormalities, diffusion-weighted MRI displayed a hyperintense lesion in only one patient, while standard MRI of this area was normal in all patients. SPECT revealed a slight but statistically nonsignificant reduction of IBZM tracer uptake in an area corresponding to the dorsal portions of the striatum in 9 of the 10 patients. TS findings support the hypothesis that structural alternations of the pallidothalamic circuit contralateral to the side of head deviation are involved in the pathogenesis of idiopathic spasmodic torticollis. TS may be more sensitive in detecting basal ganglia alterations than MRI.

Adult↗
PubMed1997

Treatment of Graves' hyperthyroidism with radioiodine: results of a prospective randomized study.

In this paper, we report the results of a randomized prospective study on radioiodine treatment in patients with Graves' hyperthyroidism. Complete data were obtained in group 1 from 98 patients 6 months after application of a standard activity of 15 mCi (555 MBq) of 131I and in group 2 from 107 patients who received a target dose of 100 Gy. In group 1, the overall success rate was 71%, but the results in the subgroups clearly were related inversely to the thyroid volume, ranging from 100% in patients with a thyroid volume < 15 mL to about 20% in those with a thyroid size of > 60 mL. In contrast, patients who received a target of 100 Gy showed very similar results, with success rates of about 40-50% in all but one subgroup. Only patients with a thyroid volume < 15 mL had a success rate of about 80%. But due to an incidental increase of uptake and/or effective half-time from the test to the therapy activity, this subgroup received a target dose of about 160 Gy. Additional calculation of the actual target dose in group 1 (standard activity) showed that, with a dose of 200 Gy, a success rate of 80% was obtained. Also, the thyroid volume reduction was related inversely to the target dose. Because the literature is abundant, only a restricted number of references are discussed that are either in agreement with our results or in sharp contrast to them. The reason for these discrepant results might be the difference in the scheme of pretreatment or the different alimentary iodine supply between, for example, Great Britain and the United States on the one hand and Germany on the the other hand.

Adult↗
PubMed1997

Value of diuresis renography in the post-natal period of assumed physiological renal immaturity.

The aim of this study was to determine if it is possible to exclude renal obstruction using diuresis renography in the first 6 weeks of life (the period of physiological renal immaturity), thus avoiding unnecessary invasive procedures, such as the Whitaker test or surgery. Diuresis renography with 123I-hippuran was performed in 27 patients aged less than 6 weeks and in 50 older children who acted as a reference group (age 6 weeks to 1 year, n = 28; age 1-10 years, n = 22). All 27 patients had significant dilatation of the pelvicalyceal system on ultrasonography. Renal curves were evaluated by mathematical curve characteristics (split renal function, counts, T-max, etc.) as the visual grade of obstruction. Whole-kidney regions of interest were defined on images summed over 30 min; renal parenchyma on images summed over 5 min. The renal curves of 18/27 patients indicated tracer accumulation and led to frusemide administration. Only two patients showed no significant response to frusemide and had to be further investigated by the Whitaker test. The frequency of kidneys with no response to frusemide revealed no significant differences in the three groups. Whole-kidney evaluation resulted in an overestimation of obstruction in 9/150 kidneys, which matches the lower correlation to the DMSA separation values for this method of evaluation. In contrast with the literature, significant post-renal obstruction can be excluded by diuresis renography in most cases in spite of renal immaturity and can help to avoid invasive procedures.

Child↗
PubMed1997

2-[123I]-iodolisuride SPET visualizes dopaminergic loss in de-novo parkinsonian patients: is it a marker of striatal pre-synaptic degeneration?

The aim of this study was to assess the correlation between the functional integrity and density of striatal dopaminergic receptors and clinical data in 15 de-novo patients with idiopathic Parkinson's disease by single photon emission tomography (SPET) using 2-[123I]-iodolisuride (ILIS), a tracer based on the D2-dopamine receptor agonist lisuride. Deficient striatal uptake of ILIS correlated with the severity of the disorder, scored by the Unified Parkinson's Disease Rating Scale (UPDRS) (n = 15; ratio of ILIS uptake: basal ganglia/cerebellum [B/C] & UPDRS I-III, Spearman R = -0.562, P = 0.013), Beck's Depression Inventory (BDI) (n = 12; B/C & BDI, Spearman R = -0.825, P = 0.0009) and the ZUNG Depression Scale (ZDS) (n = 11; B/C & ZDS, Spearman R = -0.7425, P = 0.008). Experimental data indicate that lisuride shows a higher affinity for pre-synaptic dopaminergic autoreceptors than for post-synaptic D2-dopamine receptors under conditions of low applied ILIS concentrations as in this study. From the results of this study and these experimental data, we speculate that ILIS-SPET can visualize pre-synaptic striatal dopaminergic degeneration in Parkinson's disease.

Aged↗
PubMed1997

Effect of specific activity on cardiac uptake of iodine-123-MIBG.

UNLABELLED: Radioiodinated meta-iodobenzylguanidine (MIBG), an analog of norepinephrine, has been used to assess myocardial sympathetic innervation. Recent in vivo studies predict enhanced cardiac uptake of this radiopharmaceutical with high specific activity. METHODS: To clarify the effect of specific activity on cardiac uptake of radioiodinated MIBG, the distribution and kinetics of no-carrier-added [123I]MIBG (> or = 7.4 TBq/mumol) were compared with those of commercial [123I]MIBG (approximately 74 MBq/mumol) in three healthy volunteers by serial imaging and blood sampling. RESULTS: Higher specific activity result in higher uptake of radioiodinated MIBG in all volunteers in the heart (p < 0.05) and liver (p < 0.05) but not in the lung (p = 0.26). Due to rapid deiodination, a more pronounced accumulation of radioactivity was present in plasma after no-carrier-added MIBG than commercial [123I]MIBG, resulting in higher background and thyroid activity after administration of the former. Calculated heart-to-liver (p = 0.96) and heart-to-lung (p = 0.42) count ratios in all volunteers revealed no significant improvement in cardiac imaging with no-carrier-added [123I]MIBG compared to commercial [123I]MIBG. CONCLUSION: This study highlights the appreciably higher in vivo deiodination of no-carrier-added [123I]MIBG compared to commercial preparation of [123I]MIBG in humans. Cardiac images acquired with no-carrier-added [123I]MIBG do not seem to be superior to those obtained with commercial MIBG.

3-Iodobenzylguanidine↗
PubMed1997

[Nuclear medicine diagnosis of pheochromocytoma].

The synthesis of radioiodinated meta-iodobenzylguanidine (MIBG), a physiologic norepinephrine analog, was first accomplished by a group from the University of Michigan. Since the first report of the detection of pheochromocytoma with MIBG in humans, there have been several studies about the role of this agent in the diagnosis of pheochromocytoma and neuroblastoma. With a sensitivity of about 90% and a specificity of nearly 100% MIBG has been shown to be a reliable diagnostic tool for the detection and follow-up of pheochromocytoma.

3-Iodobenzylguanidine↗
PubMed1997

SPECT-evaluation of the monoamine uptake site ligand [123I](1R)-2-beta-carbomethoxy-3-beta-(4-iodophenyl)-tropane ([123I]beta-CIT) in untreated patients with suspicion of Parkinson disease.

BACKGROUND: For a few years, data on SPECT-imaging of dopamine transporters with the cocaine derivate [123I](1R)-2-beta-carbomethoxy-3-beta-(4-iodophenyl)-tropane ([123I] beta-CIT) have been reported mostly in healthy subjects or animals. This study reflects our preliminary results with SPECT-imaging of dopamine transporters using the cocaine analogue 123-beta-CIT in patients with untreated (de novo) parkinsonism. METHODS: In 33 patients with clinical suspicion of Parkinson disease and 5 healthy controls, SPECT-imaging of dopamine transporters was performed 1, 4, and 24 hours after injection of 180 MBq of 123I-beta-CIT, which was generated by iododestannylation. None of the patients or controls had been treated before with neuroleptical drugs or any other pharmaceuticals with known binding to the dopamine transporters. Clinical symptoms were staged by the scales Hoehn-Yahr (HYS), Unified Parkinson Disease Rating Scale (UPDRS), and the self-rating scale of Beck depression inventory (BDI). For evaluation, striatal/cerebellar ratios were calculated to every time point. RESULTS: Significant correlations of 123I-beta-CIT uptake could be stated compared to UPDRS, HYS, and BDI values (Spearman correlation, p < 0.05). The symptoms of rigor and akinesia showed a significant correlation with the beta-CIT uptake, whereas the symptom of tremor failed, which may be caused by the location of tremor symptoms out of the striatum. Comparing the controls, a significant (p < 0.01) decrease of tracer uptake in parkinsonian patients is stated on the images at 24 hours p.i. In our patients, tracer uptake does not depend significantly on duration of disease and age. CONCLUSION: 123I-beta-CIT seems to be a promising tool in imaging of untreated parkinsonian patient.

Adult↗