Measuring the Autistic Women's Experience (AWE).

We developed a Dutch questionnaire called the Autistic Women's Experience (AWE) and compared its psychometric properties to the Autism Spectrum Quotient (AQ). Whilst attenuated gender differences on the AQ have been widely replicated, this instrument may not fully capture the unique experience of autistic women. The AWE was co-developed with autistic women to include items that reflect autistic women's experience. We investigated the AWE (49 items) and compared it with the AQ (50 items) in Dutch autistic individuals (N = 153, n = 85 women) and in the general population (N = 489, n = 246 women) aged 16+. Both the AQ and AWE had excellent internal consistency and were highly and equally predictive of autism in both women and men. Whilst there was a gender difference on the AQ among non-autistic people (men > women), there was no gender difference among autistic people, confirming all earlier studies. No gender differences were detected on the AWE overall scale, yet subtle gender differences were observed on the subscales. We conclude that the AQ is valid for both genders, but the AWE provides an additional useful perspective on the characteristics of autistic women. The AWE needs further validation in independent samples using techniques that allow for testing gender biases, as well as a confirmatory factor analysis in a larger sample.

Comparison of bone scintigraphy with bone markers in the diagnosis of bone metastasis in lung carcinoma patients.

This study was designed to evaluate the utility of the bone markers total alkaline phosphatase (TAP), bone-specific alkaline phosphatase (BAP), aminoterminal propeptide of type I collagen (PINP), carboxyterminal propeptide of type I collagen (PICP), pyridinoline crosslinks (PYD), deoxypyridinoline crosslinks (DPD), cross-linked carboxyterminal telopeptide of type I collagen (ICTP), cross-linked carboxyterminal telopeptide of type I collagen (CTx, beta-CrossLaps) and tartrate-resistant acid phosphatase 5b (TRAP 5b) in comparison with bone scintigraphy for the diagnosis of bone metastasis in lung carcinoma patients. The study population consisted of 49 patients with bone metastasis confirmed by plain radiography and/or computed tomography, 89 patients without bone metastasis, 12 patients with benign lung diseases and 18 healthy persons. All patients were of male gender. The bone markers were measured using commercially available tests. Serum and urine were collected from fasting patients at the time of bone scan between 7.00 and 8.00 a.m. The sensitivity of bone scintigraphy was 100%, its specificity 76.4%, resulting in a diagnostic efficiency of 84.8%. The positive predictive value was calculated to be 70% and the negative one to be 100%. The concentrations of the bone markers TAP, BAP, PINP, PYD, DPD and ICTP were significantly higher in patients with bone metastasis than in those without bone metastasis (p<0.01). The levels of PICP and CTx only tended to be higher in the patients with bone metastasis compared to those without bone metastasis. There was no significant difference in the TRAP 5b levels between the two groups. There was also no difference in the marker levels between osteoblastic, osteolytic and mixed osteoblastic-osteolytic lesions. Contrary to BAP, PICP, CTx and TRAP 5b, the markers TAP, PINP, PYD, DPD and ICTP were found to be higher (p<0.01-0.05) in patients with bone metastasis than in patients with benign lung diseases. In addition, PYD, DPD and ICTP differentiated patients with benign lung diseases from the healthy controls. Based on cut-off values that correspond to 95% specificity in the group of healthy persons, the sensitivity of the marker assays were as follows (specificity in brackets): TAP 33.3% (97.5%), BAP 22% (100%), PINP 18.4% (97.5%), PICP 2.1% (95.2%), PYD 91.8% (24.1%), DPD 83.7% (34.5%), ICTP 75.5% (44.6%), CTx 45.8% (77.5%) and TRAP 5b 14% (84%). The corresponding data for the diagnostic efficiency were as follows: TAP 73.6%, BAP 77.1%, PINP 67.7%, PICP 61.1%, PYD 48.5%, DPD 55.2%, ICTP 56.1%, CTx 65.6% and TRAP 5b 58.7%, respectively. The positive predictive values ranged from 20% (PICP) to 100% (BAP) and the negative values from 62.7% (PICP) to 84% (PYD). In the ROC analysis, TAP, followed by RAP, PINP and PYD, showed the best performance. The levels of TAP, BAP, PINP, PYD, DPD and ICTP were found to be higher in the patients with bone metastasis compared to those with metastastic lesions in other sites (p<0.01, except for ICTP having a p value of < 0.05). The levels of TAP, BAP, PYD, DPD and ICTP increased significantly with the number of metastases. There was also a steady increase in T scores of the markers PINP, PYD, DPD and ICTP with the extent of the metastatic bone disease. It is concluded that the currently available bone markers cannot replace bone scintigraphy, either for screening or in the diagnosis of bone metastasis, in lung carcinoma patients. However, a panel consisting of TAP, BAP, PINP, PYD, DPD and ICTP may be of some value as an adjunct tool to bone scintigraphy for this purpose.

CYFRA 21-1 is a prognostic determinant in non-small-cell lung cancer: results of a meta-analysis in 2063 patients.

The purpose of this study was to determine the prognostic significance of a high pretreatment serum CYFRA 21-1 level (a cytokeratin 19 fragment) adjusted for the effects of well-known co-variables in non-small-cell lung cancer (NSCLC). This meta-analysis based on individual updated data gathered comprehensive databases from published or unpublished controlled studies dealing with the prognostic effect of serum CYFRA 21-1 level at presentation in NSCLC of any stage (nine institutions, 2063 patients). Multivariate regression was carried out with the Cox model. The proportional hazard assumption for each of the selected variables retained in the final model was originally checked by log minus log plots baseline hazard ratio. The follow-up ranged from 25 to 78 months. A total of 1616 events were recorded. In the multivariate analysis performed at the 1-year end point, a high pretreatment CYFRA 21-1 level was an unfavourable prognostic determinant in all centres except one (Hazard ratio (95% confidence interval): 1.88 (1.64-2.15), P<10(-4)). Other significant variables were stage of the disease, age and performance status. Within the first 18 months, the procedure disclosed a nearly similar hazard ratio for patients having a high pretreatment serum CYFRA 21-1 level (1.62 (1.42-1.86), P<10(-4)). For patients who did not undergo surgery, the hazard ratio during the first year of follow-up was 1.78 (1.54-2.07), P<10(-4). Finally, in the surgically treated population, at the 2-year end point, a high pretreatment CYFRA 21-1 and a locally advanced stage remained unfavourable prognostic determinants. In conclusion CYFRA 21-1 might be regarded as a putative co-variable in analysing NSCLC outcome inasmuch as a high serum level is a significant determinant of poor prognosis whatever the planned treatment.

Cathepsin B, plasminogenactivator-inhibitor (PAI-1) and plasminogenactivator-receptor (uPAR) are prognostic factors for patients with non-small cell lung cancer.

To evaluate the possible role of cysteine proteases and serine proteases, as well as their respective inhibitors and receptors, as new prognostic factors in NSCLC, we examined, for the first time, 10 biological parameters related to three proteolytic systems within a homogeneous collective of 147 cases of NSCLC. Activities (cath B(AT), cath B(A7.5)) and protein levels of cath B(C), cath L(C), uPA, PAI-1, uPAR [measured by three different assays uPAR (ADI), uPAR (HD13), uPAR (IIIF10)] and TF were measured in homogenates of lung tumour tissue and corresponding non-malignant lung parenchyma. Total cath B activity (cath B(AT)) and enzymatic activity of the fraction of cath B, which is stable and active at pH 7.5 (cath B(A7.5)), were determined by a fluorogenic assay using synthetic substrate Z-Arg-Arg-AMC. The concentrations of cath B(C), cath L(C), uPA, PAI-1, uPAR and TF were determined by ELISAs. uPAR was determined using three different ELISA formats. The median levels of cath B(AT) (5.1-fold), cath B(A7.5) (2.5-fold), cath B(C), (8.5-fold), cath L(C) (6.6-fold), uPA (6.5-fold), PAI-1 (4.2-fold), uPAR (ADI) (2.2-fold), uPAR (HD13) (4.0-fold) and uPAR (IIIF10) (2.6-fold) were higher in tumour tissue compared to the lung parenchyma. Cath B(AT), cath B(A7.5) and cath B(C) in primary tumours correlated with lymph node metastases. Regarding histologies, the concentration of PAI-1 seems to be associated with the histological cell types of NSCLC. We found the highest values of PAI-1 in large cell carcinoma > SCC, AC > carcinoid and lowest values in metastases of primary tumours of other organs. Only PAI-1 was significantly increased in poorly-differentiated cells (G3) compared to well- and moderately- differentiated cells (G1/G2). PAI-1 significantly correlated with cath B(AT) and cath B(A7.5) with uPAR (ADI), uPAR (HD13), uPAR (IIIF10) with uPA, and only weakly with TF, but not with cath B(C) and cath L(C). Significant correlations with overall survival in the total population of NSCLC patients were observed in univariate analysis for cath B(AT), cath B(C), PAI-1, uPAR (ADI), uPAR (HD13), and uPAR (IIIF10). Cath L(C) was not significantly associated with poor prognosis. Regarding the histological tumour type, only in patients with squamous cell carcinomas did cath B(A7.5) and PAI-1 remain significant prognostic factors. In multivariate survival analysis only two proteolytic factors, PAI-1 and uPAR (III101F), stayed significant. In conclusion, among 10 biological parameters evaluated within the same cohort of patients, only PAI-1, uPAR (ADI), uPAR (HD13), uPAR (IIIF10), cath B(AT) and cath B(C) are prognostic factors for overall survival of NSCLC patients. Moreover, PAI-1 and uPAR (IIIF10) add independent prognostic information with regard to established clinical and histomorphological factors in NSCLC.

[MR angiography of the coronary arteries: comparison of the blood pool contrast medium Gadomer and Gd-DTPA in pigs]. / MR-Angiographie der Koronararterien: Vergleich des Blutpoolkontrastmittels Gadomer mit Gd-DTPA am Schwein.

AIM: To investigate the signal-enhancing effects of the macromolecular contrast medium Gadomer in MR angiography of the coronary arteries compared to Gd-DTPA. MATERIAL AND METHODS: A total of 15 MRI examinations of the heart were performed in pigs at 1.5 T using a pulse-triggered, segmented 3D FLASH sequence with data acquisition during breathhold before and up to 30 min after contrast medium injection. Gadomer was investigated at two doses (0.05 and 0.1 mmol Gd/kg), Gd-DTPA at one (0.3 mmol Gd/kg) (n = 5 examinations per dose). Standard sequences without magnetization preparation were supplemented by sequences with magnetization saturation applied before data acquisition before and immediately after contrast medium injection. Analysis comprised quantitative determination of blood and myocardium signal to noise (S/N) and contrast to noise (C/N) and qualitative assessment of several parameters of image quality and coronary artery visualization. RESULTS: Gadomer leads to a significant C/N increase between blood and myocardium compared to the unenhanced examination and the increase is longer-lasting than that produced by Gd-DTPA (Gd-DTPA: only directly after injection; Gadomer: up to 5 min post injection at 0.05 mmol Gd/kg, up to 10 min at 0.1 mmol Gd/kg). The qualitative evaluation shows that visualization of the coronary arteries and branch vessels is significantly better with Gadomer at both doses than with Gd-DTPA. Magnetization saturation increases the C/N in combination with Gd-DTPA and at the higher dose of Gadomer with the latter producing a higher increase in C/N values. CONCLUSION: Gadomer is a suitable contrast medium for MR angiography of the coronary arteries with the dose of 0.1 mmol Gd/kg being superior to 0.05 mmol Gd/kg due to a longer imaging window.

Pharmacokinetics of Gadomer-17, a new dendritic magnetic resonance contrast agent.

RATIONALE AND OBJECTIVES: Gadomer-17 is a new magnetic resonance (MR) contrast medium presently in clinical development. It is a dendritic gadolinium (Gd) chelate carrying 24 Gd ions. This study investigated the pharmacokinetic behavior of this contrast medium. METHODS: The pharmacokinetics of Gadomer-17 were investigated in different species (rat, rabbit, dog, monkey) for up to 7 days after intravenous (i.v.) injection of 25-100 micromol/kg body weight. In addition, elimination and biodistribution were evaluated after single i.v. injection of Gadomer-17 in rats. RESULTS: After i.v. injection Gadomer-17 distributes almost exclusively within the intravascular space without significant diffusion into the interstitial space. The volume of distribution (Vc) in the initial or alpha-phase ranged from 0.04 l/kg (rats, rabbits) to 0.06 l/kg (monkeys) and 0.07 l/kg (dogs), which reflects mainly the plasma volume. The blood/plasma concentration profile was found to be biphasic. The volume of distribution at a steady state is clearly smaller than that of other contrast media, which distribute to the extracellular space. After single i.v. injection in rats, the dendritic contrast medium was rapidly and completely eliminated from the body, mainly via glomerular filtration. No long-term accumulation or retention of the nonmetabolized agent was detectable in organs or tissues. CONCLUSIONS: Gadomer-17 is a promising new MR contrast medium that has an intravascular distribution and a rapid renal elimination.

Cysteine proteinase cathepsin H in tumours and sera of lung cancer patients: relation to prognosis and cigarette smoking.

In order to evaluate the role of cysteine peptidase cathepsin H (Cath H) in human lung cancer its protein levels were determined in 148 pairs of lung tumour tissue and adjacent non-tumourous lung parenchyma using the enzyme-linked immunosorbent assay technique. Additionally, Cath H levels were determined in sera of 171 patients with malignant tumours, 34 patients with benign lung diseases and 47 healthy controls. The median level of Cath H in tumour tissue was 0.64 times that in the corresponding lung parenchyma. Relating tumour levels with histological type we found higher Cath H levels in small-cell and adenocarcinomas and lower levels in squamous cell carcinoma, large-cell carcinoma and secondary tumours. A significant difference in Cath H level between lung tumour tissue and non-tumourous lung parenchyma was associated with the group of cigarette smokers (156 vs 263 ng mg(-1) protein, P < 0.001). For this group of patients Cath H tumour levels correlated with the survival rate, while for the entire patient population this was not the case. Smokers with high tumour levels of Cath H experienced poor survival. Cath H was significantly higher in sera of patients with malignant and benign lung diseases than in control sera (P < 0.001). The increase was significant for all histological types, being the highest in small-cell and squamous cell carcinomas. Our study reveals that in lung tumours there is different behaviour of Cath H compared with other cysteine peptidases, e.g. cathepsin B and cathepsin L. Variations between tissue and serum levels of Cath H indicate either reduced expression or enhanced secretion of this enzyme in lung tumours.

Contrast-enhanced high resolution magnetic resonance imaging of pigmented malignant melanoma using Mn-TPPS4 and Gd-DTPA: experimental results.

The aim of this study was to evaluate the potential of the paramagnetic metalloporphyrin Mn-TPPS4 (using Gd-DTPA as the reference) for magnetic resonance imaging (MRI) of pigmented malignant melanoma in an animal model. High resolution MRI (2.0 T, 2.0 cm surface coil, T1-weighted FLASH two-dimensional sequence) was performed on 15 mice (C57bl6) with intracutaneous implanted melanoma (B16F1) before and after intravenous administration of Gd-DTPA (Magnevist, Schering AG, Berlin, Germany) and Mn-TPPS4 (Porphyrin Products, Logan, Utah, USA). The images were evaluated quantitatively by calculating the percentage enhancement, the slope of the signal intensity-to-time curves, the percentage increase in the signal intensity, and the signal-to-noise and contrast-to-noise ratios. The qualitative evaluation was accomplished by visual assessment of the enhancement, the demarcation of the tumours from the surrounding tissue, and the homogeneity of the tumours. Contrast medium-enhanced images showed an increase in signal intensity for all the tumours, with no significant difference between the contrast media. Specific accumulation of the contrast media in the melanoma could not be proved. Demarcation of tumours from the surrounding tissue is better after administration of contrast media; regressive changed areas were better depicted.

Pharmacokinetics of 1M gadobutrol in patients with chronic renal failure.

RATIONALE AND OBJECTIVES: To investigate the pharmacokinetics of 1M gadobutrol as a new neutral MR contrast agent in patients with impaired renal function. METHODS: Twenty-one patients with impaired renal function and any indication for a contrast-enhanced MRI were enrolled into this prospective study and classified in two subgroups according to their creatinine clearance (group 1, 30-80 mL/ min; group 2, 30 mL/min or less, not requiring dialysis). Eleven patients were assigned to the lower dose of 0.1 mmol Gd/kg and 10 patients to the higher dose of 0.3 mmol Gd/kg. To calculate pharmacokinetic parameters, urine and venous blood samples were drawn at baseline and up to 72 hours for group 1 and 120 hours for group 2 after administration of gadobutrol. RESULTS: The predominant extracellular distribution of gadobutrol at steady state did not change according to the degree of renal impairment. The mean elimination half-life of gadobutrol increased to 7.4 +/- 2.6 hours (0.1 mmol/kg) and 5.4 +/- 1.5 hour (0.3 mmol/kg) in group 1 and to 17.9 +/- 6.2 hours (0.1 mmol/kg) and 20.4 +/- 16.9 hours (0.3 mmol/kg) in group 2, compared with 1.5 hours in healthy volunteers. The relation between serum (tbeta) and urine (t(elim)) elimination half-lives, as well as total serum and renal clearance, indicated renal elimination as the main pathway of elimination. The recovery of gadobutrol in the urine of group 1 was complete within 72 hours for both dosage levels. Patients with severe renal impairment showed a mean recovery of 80.1% (0.1 mmol/kg) and 85.3% (0.3 mmol/kg) within the observation period of 120 hours. CONCLUSIONS: The half-life of gadobutrol is prolonged in patients with impaired renal function, but elimination by means of the kidneys is the predominant route.

Cathepsin B in infiltrated lymph nodes is of prognostic significance for patients with nonsmall cell lung carcinoma.

BACKGROUND: Tumor cells require specific proteolytic enzymes for invasion and metastasis, including lysosomal peptidases--cathepsins. Cathepsin B is a lysosomal cysteine peptidase, which appears to play a major role in invasion and metastasis of human tumors. In this study, the authors focused on the possible role of cathepsin B in lymphogenic metastasis by investigating the enzyme localization and its activity in lung tumors and corresponding tumor-infiltrated lymph nodes. METHODS: Cathepsin B activity was determined in lung tumors, lung parenchyma, and tumor cell-infiltrated and noninfiltrated regional lymph nodes of the same patient. The authors investigated 35 cancer patients suffering from nonsmall cell lung carcinoma. Cathepsin B throughout activity was measured by cleavage of the fluorogenic substrate Z-Arg-Arg-AMC at pH 6.0. RESULTS: The median specific cathepsin B activity was highest in tumors, followed by the infiltrated lymph nodes, noninfiltrated lymph nodes, and lung parenchyma. The authors showed a significant 1.8-fold increase in cathepsin B activity in tumor-infiltrated lymph nodes compared with noninfiltrated regional lymph nodes and a 4.5-fold increase in lung tumor tissue compared with lung parenchyma. High cathepsin B activity, both in tumors and tumor cell-infiltrated lymph nodes, indicated poor prognosis for overall survival. Immunohistochemical analysis showed the presence of cathepsin B in histiocytes and tumor cells but not in lymphocytes of lymph node tissue. CONCLUSIONS: The authors' findings on higher cathepsin B levels in tumor cell-infiltrated lymph nodes show that increased level of cathepsin B activity is characteristic of the invasive tumor cell phenotype. This corroborates the hypothesis, that tumor cell associated cathepsin B may play a role in lymphogenic metastasis. The authors' results support the use of lymph node associated cathepsin B as a prognostic factor for survival of patients with lung carcinoma.

Comparison of Gadomer-17 and Gd-DTPA in image quality of contrast-enhanced MR angiographies using flow phantom model.

The purpose of this study was to compare the image quality of 3D-TOF MR angiography (MRA) using Gadomer-17 with that using Gd-DTPA in a flow phantom model, and to present preliminary data about the proper dose concentration of Gadomer-17. In the visual analysis of vessel conspicuity, we compared the quality of pre- and post-contrast MIP images. For quantitative analysis, the signal intensities were measured in the axial base 3D-TOF images, and then the relative contrast enhancement was calculated. The results of our studies were that: 1. Maximal signal intensities were obtained at 1 mmol/L of Gadomer-17 and 4 mmol/L of Gd-DTPA. 2. Flow-related signal loss was decreased by Gd-DTPA proportional to the concentration, but Gadomer-17 did not show such a dose accumulative effect. In conclusion, after comparing the results of Gd-DTPA, it was clear that improved MRA images and higher signal intensities of vessels were obtained when lower concentrations of Gadomer-17 were used.

Fluorometric microassays for the determination of cathepsin L and cathepsin S activities in tissue extracts.

We established a continuous semi-microassay, and for large-scale studies both a stopped and a continuous microtiter plate assay for the fluorometric determination of cathepsin L and cathepsin S activities in body fluids, tissues or cell extracts in the presence of cathepsin B. For the detection of enzymatic activities we used the synthetic substrate Z-Phe-Arg-AMC, and for discrimination between cathepsin L, S and cathepsin B the specific inhibitor CA-074 for blocking interfering cathepsin B activities was applied. Furthermore, we took advantage of the stability of cathepsin S at pH 7.5 for further differentiation between cathepsin L and cathepsin S activities. The kinetic assays were characterized in terms of imprecision, analytical sensitivity, accuracy and substrate concentration. The within-run coefficients of variation were found to be 4.9%-7.2% for the continuous semi-microassay, 10.3%-11.7% for the stopped, and 4.5%-11.8% for the continuous microtiter plate assay. The between-days coefficients of variation for the continuous semi-microassay were 8.1%-8.9%, while for the stopped and continuous microtiter plate assays the coefficients were 11.2%-13.5% and 5.8%-12.2%, respectively. Compared to the continuous semi-microassay, the stopped and the continuous microtiter plate assays showed 3-fold and 11-fold higher sensitivity, respectively. Comparison between the continuous enzyme activity assays at substrate concentrations of 40 microM and 200 microM demonstrated a significant correlation of r = 0.97 and r = 0.99, respectively. The newly developed microtiter plate assay will allow efficient, sensitive and high precision determination of cathepsin L and cathepsin S activities in large-scale studies of cysteine-cathepsin dependent diseases.

CYFRA 21-1 in the follow-up of inoperable non-small cell lung cancer patients treated with chemotherapy.

The introduction of new regimens in the chemotherapy of inoperable non-small cell lung cancer (NSCLC) patients provides a useful extension of survival probability that may now justify the application of tumor markers for the disease monitoring. In a prospective study of 48 consecutive NSCLC patients with TNM stages IIIB/IV we compared changes in the serum levels of the cytokeratin 19 fragment CYFRA 21-1 with the clinical evaluations of response to therapy. CYFRA 21-1 levels were measured using the enzyme immunoassay of Boehringer, Mannheim (Germany). Clinical response to therapy was evaluated according to standard criteria of the WHO. For the assessment of response to therapy by changes in the marker levels the difference between two consecutive levels must exceed 30%. This value is based on the formula: Difference = 2 square root of 2 x CV (CV: inter-assay coefficient of variation of the marker test). CYFRA 21-1 was found to be elevated in 29/48 (60.4%) patients prior to therapy and in 10/48 (20.8%) patients at tumor progression. 91 evaluations have been recorded in these 39 patients. The overall concordance between changes in the marker levels and the clinical assessment was 59.3%. The decrease of CYFRA 21-1 levels at remission was rather low resulting in a concordance of only 42.9%, i.e. marker assays cannot replace the clinical restaging by imaging modalities. In contrast, changes in the marker levels at progression did exceed the required 30% in the majority of cases (64.7%). Most of discordant results (40.7%) could be explained by insufficient decrease or increase of CYFRA 21-1 levels or by extended lead-time. The most striking result was the detection of progressive disease by rising marker levels. Except one case, there was no false-positive elevation of CYFRA 21-1 levels. It is concluded that the detection of progressive disease by rising CYFRA 21-1 levels may avoid continuation of ineffective treatment.

[Mn-TPPS4 in the diagnosis of malignant skin tumors. In vivo studies with high resolution magnetic resonance tomography in melanotic melanoma]. / Mn-TPPS4 in der Diagnostik von malignen Hauttumoren. In-vivo-Untersuchungen mittels hochauflösender Magnetresonanztomographie an melanotischen Melanomen.

PURPOSE: Some authors postulate an avidity of certain porphyrin derivatives for tumors. The aim of this study was to examine the contrast enhancement of implanted melanotic melanoma after application of Mn-TPPS4 to achieve a better characterization of this malignant skin tumor. MATERIAL AND METHOD: High-resolution MR imaging (2.0 Tesla, 2.0-cm surface-coil, T1-weighted FLASH-2D-sequence) was performed on 15 mice (C57b16) with intracutaneous implanted melanoma (B16F1), before and after intravenous administration of either Gd-DTPA (Magnevist, Schering, Berlin) as a reference contrast medium, or Mn-TPPS4 (Porphyrin Products, Schering, Berlin). The images were evaluated quantitatively by calculating percentage enhancement, slope of signal intensity-to-time curves, percentage increase of the signal intensity, signal-to-noise and contrast-to-noise-ratios. The qualitative evaluation was accomplished by visual assessment of the enhancement, the demarcation of the tumors from the surrounding tissue and the homogeneity of the tumors. RESULTS: Contrast medium-enhanced images showed an increased signal intensity from all tumors with no signifikant difference between the contrast media. Demarcation of tumors from the surrounding tissue was better following administration of contrast media; regressive and altered areas was more clearly depicted. CONCLUSION: A specific accumulation of the metalloporphyrin Mn-TPPS4 in melanotic melanoma could not be proved. Based on the small and insignifikant differences in the results obtained with the two contrast media, and on the side effects of the metalloporphyrin, the usefulness of Mn-TPPS4 as a contrast medium for MRT is limited.

Mechanism of gadophrin-2 accumulation in tumor necrosis.

The molecular mechanism by which gadophrin-2 targets necrotic tumor tissue was investigated. Biodistribution studies and magnetic resonance imaging (MRI) and histologic/autoradiographic correlation were performed in xenograft mouse models bearing human tumors (HT 29, WiDr, LX 1). Binding of gadophrin-2 to DNA, lipids, or proteins was determined by fluorescence spectrophotometry. Protein binding was determined by dialysis and gel electrophoresis. Accumulation of gadophrin-2 was low (<0.7% injected dose/g tissue at 24 hours after injection) in viable tumor but higher in necrotic tumor regions and was readily detectable by MRI. Within a given tumor, the agent preferentially localized in the periphery of necrotic areas. Within these regions gadophrin-2 was bound to interstitial albumin and not other proteins, lipids, or DNA. Tumoral accumulation of gadophrin-2 most likely occurs through its binding to plasma albumin and subsequent slow extravasation into the tumor interstitium.

Interphase cytogenetic diagnosis of bladder cancer on cells from urine and bladder washing.

In order to determine the value of fluorescence in situ hybridization (FISH) in the diagnosis and follow-up of bladder cancer interphase cytogenetics was performed on cells from urine and bladder washings. 50 ml of urine or bladder washings were collected. FISH was carried out using centromere probes for chromosomes 7, 8, 9 and 12 according to standard protocols. In each case 100 cell nuclei were analysed. Fifty-four samples from urine and 67 samples from bladder washing were analysed by FISH in comparison with results obtained by conventional cytology. Sensitivity of detection of tumor cells by FISH was 68.5% in urine and 63% in bladder washings regardless of tumor stage and grade. Sensitivity obtained by conventional cytology was 50% in urine and 77.3% in bladder washings. FISH on cells from urine samples is an effective complement to the standard urine cytology. Using centromere probes this approach is characterized by high specificity and sensitivity in tumors with T-category higher than pTa and grade higher than G1.