Relevant bleeding diathesis due to acquired factor XIII deficiency

Acquired factor XIII (FXIII) deficiency is associated with reduced clot firmness and increased bleeding in patients undergoing major surgery. In contrast, only limited information is available on the haemostatic relevance of acquired FXIII deficiency in non-surgical patients.

An 81-year-old patient, who had experienced acute type-A dissection of the aorta eight years earlier, presented with a 3-year history of progressive mucocutaneous and softtissue bleeding. Diagnostic work-up was unremarkable for global coagulation tests, but FXIII and alpha2-antiplasmin were decreased to 33% and 27%, respectively, while plasma D-dimer was elevated to > 35 mg/l. A FXIII inhibitor was excluded by mixing studies. CT scanning revealed a massively elongated and progressively dilated aorta with a false lumen reaching from the left carotid artery to the iliac bifurcation. Bleeding control was achieved by single doses of FXIII at 20-30 IU/ kg body weight and tailored oral tranexamic acid.

Acquired FXIII deficiency with activity levels of 30–35% may confer a severe bleeding tendency in non-surgical patients, especially in the context of increased thrombin an fibrin generation.

Abstract S6-05: Comprehensive comparison of prognostic signatures for breast cancer in TransATAC

Background: A number of prognostic signatures have been developed for the prediction of breast cancer recurrence in the past decade. We have developed two signatures (Clinical Treatment Score (CTS), four immunohistochemical markers (IHC4)) and validated four prognostic signatures (Oncotype Dx Recurrence Score (RS), PAM50-based Prosigna (ROR), Breast Cancer Index (BCI), and EndoPredict (EPclin)) in the TransATAC cohort. Here, we compare the prognostic performance of these six signatures for distant recurrence (DR) in years 0-10, and specifically in years 5-10 after treatment cessation.

Methods: 1231 postmenopausal women with hormone receptor positive and HER2-negative breast cancer had at least one test performed. Of these, 818 women had data on all six signatures available. IHC4, RS and BCI (linear) are molecular only signatures whereas CTS, ROR and EPclin include clinicopathological factors. The primary endpoint was DR and the primary objective was to compare the prognostic value of the six signatures in terms of DR for years 0-10, 0-5, and 5-10. Secondary objectives included the comparison of the prognostic performance for node-negative and node-positive patients separately and the additional prognostic performance of each signature to the others. Likelihood ratio statistics (LR-χ2) were used to assess the prognostic information of each signature alone or in combination with other signatures.

Results: Median follow-up for this analysis was 9.94 years (IQR 8.01-10.09) and a total of 126 DR were recorded. 818 women with HER2-negative disease for whom data of all six signatures were available were included in this analysis. For all patients, CTS and EPclin were the most prognostic signatures in years 0-10 (CTS: LR-χ2=124.9; EPclin: LR-χ2=116.2) and years 5-10 (CTS: LR-χ2=59.6; EPclin: LR-χ2=56.8) in the univariate analysis. The other four signatures performed similarly well in years 0-5, but of those only BCI and ROR provided substantial prognostic information in years 5-10 (BCI: LR-χ2=25.3; ROR: LR-χ2=43.8). In multivariate analyses comparing the added information of the molecular signatures over CTS, IHC4 and BCI provided the most information (IHC4: ΔLR-χ2=19.0; BCI: ΔLR-χ2=19.8). In node-negative patients (72.3%), the ROR showed the most prognostic value in years 0-10 (LR-χ2=48.6) and years 5-10 (LR-χ2=31.3) whereas the RS was least prognostic in this patient group. For patients with node-positive disease (27.7%), the CTS and EPclin were the most prognostic and the other four signatures provided much less prognostic information for this patient population (data not shown).

Conclusion: Overall, the CTS and EPclin were the most prognostic signatures for DR and also added significant prognostic value to the other scores in women with HER2-negative disease, primarily due to the incorporation of nodal status in these signatures. For women with node-negative disease, the ROR, BCI, and EPclin signatures provided most prognostic value whereas for those with positive nodes CTS and EPclin were most prognostic. Our analyses showed that the inclusion of clinic-pathological factors into gene signatures is highly important for deriving an accurate prognostic assessment, particularly in node-positive patients.

Citation Format: Sestak I, Buus R, Cuzick J, Dubsky P, Kronenwett R, Ferree S, Sgroi D, Schnabel C, Baehner R, Mallon E, Dowsett M. Comprehensive comparison of prognostic signatures for breast cancer in TransATAC [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr S6-05.

Abstract P2-09-15: A multi-institutional, prospective study of incorporating the genomic platform breast cancer index as a tool for decision-making regarding extension of adjuvant endocrine therapy

Background: Extending adjuvant endocrine therapy (AET) for hormone responsive breast cancer (HRBC) from 5 to 10 years is beneficial for many in preventing late relapse. Current decision-making regarding extension relies on a decision-making process that weighs non-personalized recurrence risks against risks and benefits of extended AET. The Breast Cancer Index (BCI, BioTheranostics Inc) has been validated to quantify the risk of late recurrence and to predict likelihood of benefit from AET extension based on an individual's tumor genomic profile. The purpose of this study was to conduct a multi-institutional study to prospectively assess the impact of BCI i) on provider's recommendation using the BCI results; 2) the confidence with decision-making; and 3) patient's satisfaction regarding extension of AET.

Methods: Patients with stage I-III HRBC treated at Yale Cancer Center and University of Pittsburgh Medical Center (UPMC), who had completed at least 3.5 years of AET were eligible. BCI was performed on FFPE samples from the original tumor sample (bioTheranostics Inc.). Patients and physicians completed pre- and post-test questionnaires examining preferences for extending AET, patients also completed anxiety and decision-conflict surveys.

Results: 140 patients [mean age 61, 80% postmenopausal, 73% stage I] were included. No extended AET was recommended for 35.3% patients' pre-testing. Reasons physicians did not recommend extended AET were perceived low risk of recurrence (87%), risk of osteoporosis (25%) and side effects (13%). Extended therapy was recommended for 65.7% patients pre-testing. Integration of BCI resulted in a change in physician treatment recommendation in 29% of patients. The recommendation for no extended AET rose to 48% and recommendation for extended AET dropped to 52% (OR=1.76 95% CI 1.08-2.85; p=.003). Of the recommendations that changed (N=41), the majority (73%) was for not extending endocrine therapy. However, 27% of recommendations were to extend endocrine therapy because of high risk or high likelihood of benefit results. More physicians felt strongly confident in their recommendation after the test result (26.4%) than before (9.3%) (OR= 3.5 95% CI 1.77-6.95; p<.0001). Satisfaction of decision increased in 23% of patients (OR=2.72 95% CI 1.66-4.46; p<.0001). Patient reported concerns including the cost, safety and benefit of extended AET decreased from pre- to post-testing (p=.025; p<.0001; p=.0012 respectively)

Conclusions: Overall, incorporation of BCI into clinical practice resulted in significant changes in physician recommendations regarding AET duration, with the majority of recommendations for no extended AET. Physicians reported increased confidence for their recommendation when incorporating the test result. There was also a significant increase in patient satisfaction and decrease in patient reported concerns regarding cost, safety and benefit of extended AET. The BCI is a tool that could be incorporated into decision-making algorithms to enhance physician confidence and patient satisfaction with recommendations for extending AET.

Citation Format: Sanft T, Berkowitz A, Schroeder B, Hatzis C, Schnabel C, Aktas B, Brufsky A, Pusztai L, vanLonden GJ. A multi-institutional, prospective study of incorporating the genomic platform breast cancer index as a tool for decision-making regarding extension of adjuvant endocrine therapy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-09-15.

Relevant bleeding diathesis due to acquired factor XIII deficiency

BACKGROUND

Acquired factor XIII (FXIII) deficiency is associated with reduced clot firmness and increased bleeding in patients undergoing major surgery. In contrast, only limited information is available on the haemostatic relevance of acquired FXIII deficiency in non-surgical patients.

CASE REPORT

An 81-year-old patient, who had experienced acute type-A dissection of the aorta eight years earlier, presented with a 3-year history of progressive mucocutaneous and soft-tissue bleeding. Diagnostic work-up was unremarkable for global coagulation tests, but FXIII and alpha2-antiplasmin were decreased to 33% and 27%, respectively, while plasma D-dimer was elevated to > 35 mg/l. A FXIII inhibitor was excluded by mixing studies. CT scanning revealed a massively elongated and progressively dilated aorta with a false lumen reaching from the left carotid artery to the iliac bifurcation. Bleeding control was achieved by single doses of FXIII at 20-30 IU/kg body weight and tailored oral tranexamic acid.

CONCLUSION

Acquired FXIII deficiency with activity levels of 30-35% may confer a severe bleeding tendency in non-surgical patients, especially in the context of increased thrombin an fibrin generation.

Prediction of late recurrences by breast cancer index in the NCIC CTG MA.17 cohort

2

Background: The MA.17 trial demonstrated that extended adjuvant endocrine therapy with letrozole after 5-y of tamoxifen markedly reduced the risk of recurrence in women with ER+ early stage breast cancer. This trial provides an opportunity to assess the ability of biomarkers to predict late recurrences in ER+ breast cancer. The Breast Cancer Index (BCI), a continuous risk index based on the combination of HOXB13:IL17BR (H:I) and the molecular grade index (MGI), estimates the individual risk of recurrence in ER+ breast cancer patients. In this study, the prognostic utility of BCI to predict late recurrences was examined.

Methods: FFPE tumor blocks were collected from patients who experienced a breast cancer recurrence up to unblinding of MA.17. Controls were matched 2:1 for age, tumor size, nodal status and prior chemotherapy, and were disease free for longer than cases. All cases were reviewed for standard histopathology and evaluated using the real-time RT-PCR BCI assay.

Results: Patient characteristics for the case-control study were similar to that from the overall study. Characteristics for cases (N=83) and controls (N=166) were not significantly different except for treatment. A higher percentage of controls compared to cases tended to be categorized as low risk by BCI (58% vs 43%), while a lower percentage of controls than cases tended to be categorized as high risk by BCI (34% vs 24%). In univariate analysis, treatment, BCI, H:I and HOXB13, but not tumor grade or MGI, were significant predictors of late recurrence. After adjusting for standard variables (age, tumor grade and treatment), BCI (OR 2.37; P=0.03), H:I (OR 2.55; P=0.04) and HOXB13 (OR 1.35; P=0.02) remained significant predictors of recurrence. HOXB13 expression at diagnosis predicted patient benefit from extended endocrine therapy with letrozole.

Conclusions: In this case-controlled study, the data demonstrate that BCI is a significant predictor of late recurrences in ER+ patients following 5-y of tamoxifen. The prognostic performance of BCI to predict late recurrences was largely dependent on HOXB13 expression. The integration of H:I and MGI within BCI provides prognostic utility for both early and late recurrences.

High bone turnover and accumulation of osteoid in patients with neurofibromatosis 1

Although it is known that neurofibromatosis 1 (NF1) patients suffer from vitamin D deficiency and display decreased bone mineral density (BMD), a systematic clinical and histomorphometrical analysis is absent. Our data demonstrate that NF1 patients display high bone turnover and accumulation of osteoid and that supplementation of vitamin D has a beneficial effect on their BMD.

INTRODUCTION

Neurofibromatosis 1 results in a wide range of clinical manifestations, including decreased BMD. Although it has been reported that NF1 patients have decreased vitamin D serum levels, the manifestation of the disease at the bone tissue level has rarely been analyzed.

METHODS

Thus, we performed a clinical evaluation of 14 NF1 patients in comparison to age- and sex-matched control individuals. The analysis included dual X-ray absorptiometry osteodensitometry, laboratory parameters, histomorphometric and quantitative backscattered electron imaging (qBEI) analyses of undecalcified bone biopsies.

RESULTS

NF1 patients display significantly lower 25-(OH)-cholecalciferol serum levels and decreased BMD compared to control individuals. Histomorphometric analysis did not only reveal a reduced trabecular bone volume in biopsies from NF1 patients, but also a significantly increased osteoid volume and increased numbers of osteoblasts and osteoclasts. Moreover, qBEI analysis revealed a significant decrease of the calcium content in biopsies from NF1 patients. To address the question whether a normalization of calcium homeostasis improves BMD in NF1 patients, we treated four patients with cholecalciferol for 1 year, which resulted in a significant increase of BMD.

CONCLUSION

Taken together, our data provide the first complete histomorphometric analysis from NF1 patients. Moreover, they suggest that low vitamin D levels significantly contribute to the skeletal defects associated with the disease.

Non-destructive and radiochemical determination of the neutron-induced production cross section of I-129 from Te and other neutron-induced cross sections on Te at 14.7 MeV

Cross sections of twelve neutron-induced reactions on tellurium at 14.7 MeV have been determined. Among them are the (n,2n) cross sections for the production of both 129Te isomers which were determined using gamma ray spectrometry. These reactions dominate the cosmogenic production of 129I in meteoroids and are therefore of special importance. In addition, the neutron-induced cross section on Te at 14.7 MeV for the production of 129I was also determined directly by accelerator mass spectrometry (AMS) after radiochemical separation. The results for the production cross section of 129I determined by the two methods agree within 5%.

On the origin of129I in rain water near Zürich

129I concentrations in precipitation at Dübendorf/Zürich, Switzerland, have been determined with monthly resolution for almost three years in the mid 1990s. The results confirm that annual mean129I concentrations in precipitation in central Europe have remained about constant since the late 1980s. Liquid and gaseous emissions from the nuclear fuel reprocessing plants at Sellafield and La Hague are discussed as the only possible sources of129I in precipitation in central Europe. Based on an upper limit estimate for iodine transferred from the sea to the atmosphere, the gaseous discharges constitute the potentially bigger129I reservoir for precipitation. Moreover, the time dependence of the annual gaseous129I releases from Sellafield and La Hague correlates much better with the129I concentrations in precipitation in central Europe since the late 1980s than does the time dependence of the liquid emissions from these sites. At monthly resolution, the129I concentrations in the precipitation samples close to Zürich exhibit a large variability. A meteorological transport analysis was carried out for four selected months with particularly low or high observed129I concentrations. It was found that meteorological transport alone, based upon assimilated wind fields and observed precipitation values, can not directly account for the large month-to-month variability.

Dementia and leukoencephalopathy due to lymphomatosis cerebri

Lymphomatosis cerebri (LC) is a rare variant of primary central nervous system lymphoma (PCNSL). Clinically, the disease typically presents with a rapidly progressive dementia and unsteadiness of gait. Its presentation on cerebral MRI, which is characterised by diffuse leukoencephalopathy without contrast enhancement, often causes diagnostic confusion1 with suspected diagnoses ranging from Binswanger's disease to leukoencephalopathy or encephalomyelitis. Here we report a patient with subacute dementia and diffuse bilateral white matter changes in the cerebral hemispheres and additional involvement of the brainstem, basal ganglia and thalamus on MRI. Initially, she was considered to suffer from an autoimmune encephalitis, transiently responded to immunosuppression but then developed multiple solid appearing cerebral lymphomas.

Galactic-cosmic-ray-produced 3He in a ferromanganese crust: any supernova 60Fe excess on earth?

An excess of 60Fe in 2.4-3.2 x 10(6) year old ferromanganese crust (237 KD) from the deep Pacific Ocean has been considered as evidence for the delivery of debris from a nearby supernova explosion to Earth. Extremely high ;{3}He/;{4}He (up to 6.12 x 10(-3)) and 3He concentrations (up to 8 x 10(9) atoms/g) measured in 237 KD cannot be supernova-derived. The helium is produced by galactic cosmic rays (GCR) and delivered in micrometeorites that have survived atmospheric entry to be trapped by the crust. 60Fe is produced by GCR reactions on Ni in extraterrestrial material. The maximum (3)He/(60)Fe of 237 KD (80-850) is comparable to the GCR (3)He/(60)Fe production ratio (400-500) predicted for Ni-bearing minerals in iron meteorites. The excess 60Fe can be plausibly explained by the presence of micrometeorites trapped by the crust, rather than injection from a supernova source.

Iodine-129 in soils from Northern Ukraine and the retrospective dosimetry of the iodine-131 exposure after the Chernobyl accident

Forty-eight soil profiles down to a depth of 40 cm were taken in Russia and Ukraine in 1995 and 1997, respectively, in order to investigate the feasibility of retrospective dosimetry of the 131I exposure after the Chernobyl accident via the long-lived 129I. The sampling sites covered areas almost not affected by fallout from the Chernobyl accident such as Moscow/Russia and the Zhitomir district in Ukraine as well as the highly contaminated Korosten and Narodici districts in Ukraine. 129I was analyzed by radiochemical neutron activation analysis (RNAA) and accelerator mass spectrometry (AMS). 127I was measured for some profiles by RNAA or ion chromatography (IC). The results for 127I demonstrated large differences in the capabilities of the soils to store iodine over long time spans. The depth profiles of 129I and of 137Cs showed large differences in the migration behavior between the two nuclides but also for each nuclide among the different sampling sites. Though it cannot be quantified how much 129I and 137Cs was lost out of the soil columns into deeper depths, the inventories in the columns were taken as proxies for the total inventories. For 129I, these inventories were at least three orders of magnitude higher than a pre-nuclear value of 0.084+/-0.017 mBq m(-2) derived from a soil profile taken in 1939 in Lutovinovo/Russia. From the samples from Moscow and Zhitomir, a pre-Chernobyl 129I inventory of (44+/-24) mBq m(-2) was determined, limiting the feasibility of 129I retrospective dosimetry to areas where the 129I inventories exceed 100 mBq m(-2). Higher average 129I inventories in the Korosten and Narodici districts of 130 and 848 mBq m(-2), respectively, allowed determination of the 129I fallout due to the Chernobyl accident. Based on the total 129I inventories and on literature data for the atomic ratio of 129I/131I=13.6+/-2.8 for the Chernobyl emissions and on aggregated dose coefficients for 131I, the thyroid exposure due to 131I after the Chernobyl accident was estimated for the inhabitants of four villages in the Korosten and of three villages in the Narodici districts. The limitations and uncertainties of the 129I retrospective dosimetry are discussed.

Quantitative monitoring of the mRNA expression pattern of the TGF-beta-isoforms (beta 1, beta 2, beta 3) during transdifferentiation of hepatic stellate cells using a newly developed real-time SYBR Green PCR

Current methods to determine the mRNA of the TGF-beta-isoforms, beta 1, beta 2, and beta 3, are not sensitive enough to detect small alterations in the expression levels. Therefore, we established a SYBR Green I-based real-time quantitative PCR procedure with fragment-specific standards. The advantage of gene-specific quantification is the possibility to be abstain from the need to compare results with a house-keeping gene having a different sequence and PCR efficiency. Reproducibility of the results and analytical variances of the real-time PCR assays were tested. In transdifferentiating rat hepatic stellate cells (HSC) the TGF-beta 1-mRNA was found to be the predominant isoform expressed followed by TGF-beta 3 and low amounts of TGF-beta 2-mRNA. An alteration of the TGF-beta 1,-beta 2, and -beta 3 ratio during HSC transdifferentiation could not be detected. Furthermore, the GAPDH mRNA expression varied during HSC activation, and thus is not recommended as a standard in real-time PCR quantifications.

Identification of a promoter in position 56 within the long control region of human papillomavirus type 18

The expression of the oncogenes E6 and E7 of the cervical cancer associated human papillomavirus type 18 was shown to be directed from the promoter in position 105 (P105), which is reportedly the only early promoter located within the long control region (LCR). However, in C33A cells transiently transfected with a reporter construct containing the LCR of HPV18 in front of the luciferase gene a transcript initiating at position 56 was present in addition to those initiating from the P105. A perfect TATA Box consensus sequence 30 bp further upstream, which is highly conserved among HPVs associated with cervical cancer, was required for the activity of this novel promoter, denoted here as P56. The P56 specific transcript obviously depends on promoter downstream sequences, since transcripts initiating from the P56 were not present when the CAT gene was cloned downstream of the LCR. We detected transcripts initiating from both the P105 and the P56 in primary keratinocytes harboring episomal HPV18 as well as in the HPV 18 positive cervical carcinoma cell lines HeLa, C4-1 and SW756. Our data suggest that in HPV18, the expression of the early viral proteins including the oncogenes might be directed from a second promoter, located within the LCR.

Wet and dry deposition of 129I in Seville (Spain) measured by accelerator mass spectrometry

Iodine-129 (T1/2 = 1.57 x 10(7) yr) concentrations have been determined by accelerator mass spectrometry in rainwater samples taken at Seville (southwestern Spain) in 1996 and 1997. This technique allows a reduction in the detection limits for this radionuclide in comparison to radiometric counting and other mass spectrometric methods such as ICP-MS. Typical 129I concentrations range from 4.7 x 10(7) 129I atoms/l (19.2%) to 4.97 x 10(9) 129I atoms/l (5.9%), while 129I depositions are normally in the order of 10(8)-10(10) atoms/m2d. These values agree well with other results obtained for recent rainwater samples collected in Europe. Apart from these, the relationship between 129I deposition and some atmospheric factors has been analyzed, showing the importance of the precipitation rate and the concentration of suspended matter in it.

Determination of 129I in atmospheric samples by accelerator mass spectrometry

A method for the radiochemical extraction of 129I from atmospheric charcoal filters and its measurement by accelerator mass spectrometry is presented. Either the 129I concentration or the 129I/127I atom ratio can be determined in the sample. With this method, air filters from Seville, in the Southwest of Spain (37.4 degrees N, 6 degrees W) have been analyzed. Sensitivities in the order of 10(4) atoms/m3 for 129I concentrations and 10(-10) for 129I/127I atom ratios are obtained. AMS measurements are performed with the 6 MV tandem accelerator at the ETH-Hönggerberg in Zurich.

Shock melting of the canyon diablo impactor: constraints from nickel-59 contents and numerical modeling

Two main types of material survive from the Canyon Diablo impactor, which produced Meteor Crater in Arizona: iron meteorites, which did not melt during the impact; and spheroids, which did. Ultrasensitive measurements using accelerator mass spectrometry show that the meteorites contain about seven times as much nickel-59 as the spheroids. Lower average nickel-59 contents in the spheroids indicate that they typically came from 0.5 to 1 meter deeper in the impactor than did the meteorites. Numerical modeling for an impact velocity of 20 kilometers per second shows that a shell 1.5 to 2 meters thick, corresponding to 16 percent of the projectile volume, remained solid on the rear surface; that most of the projectile melted; and that little, if any, vaporized.

On the analysis of iodine-129 and iodine-127 in environmental materials by accelerator mass spectrometry and ion chromatography

Based on a review of literature about the abundances of 129I (T1/2 = 15.7 Ma) in the environment we show that there is a severe lack of knowledge, in particular about natural, pre-nuclear levels. Among the two analytical techniques which are sensitive enough to investigate 129I in environmental materials, namely radiochemical neutron activation analysis (RNAA) and accelerator mass spectrometry (AMS), only AMS is capable of covering the natural, pre-nuclear levels. Since such AMS measurements require chemical separation of iodine from the matrix, a wide variety of separation schemes are necessary for environmental analyses. We report here on such schemes for the analysis of soils, plants and soft tissue. They are applied exemplarily to analyses of soils from the vicinity of Chernobyl. For chemical separations prior to analysis, contamination control and blank analyses are essential. Here, we discuss quality control procedures in detail, both for RNAA and AMS. In the case of AMS we use ion-chromatography (IC) for the determination of stable iodine. The IC analysis is included in the separation schemes for environmental materials. First AMS-analyses of terrestrial biospheric materials demonstrate that natural environmental levels of 129I are lower than previously deduced from investigations using RNAA, but higher than expected from model calculations. AMS is capable of providing the missing knowledge about the radioecology of 129I.

Hox proteins have different affinities for a consensus DNA site that correlate with the positions of their genes on the hox cluster

The hox genes, members of a family of essential developmental regulators, have the intriguing property that their expression in the developing murine embryo is colinear with their chromosomal organization. Members of the hox gene family share a conserved DNA binding domain, termed the homeodomain, which mediates interactions of Hox proteins with DNA regulatory elements in the transcriptional control regions of target genes. In this study, we characterized the DNA binding properties of five representative members of the Hox family: HoxA5, HoxB4, HoxA7, HoxC8, and HoxB1. To facilitate a comparative analysis of their DNA binding properties, we produced the homeodomain regions of these Hox proteins in Escherichia coli and obtained highly purified polypeptides. We showed that these Hox proteins interact in vitro with a common consensus DNA site that contains the motif (C/G)TAATTG. We further showed that the Hox proteins recognize the consensus DNA site in vivo, as determined by their ability to activate transcription through this site in transient transfection assays. Although they interact optimally with the consensus DNA site, the Hox proteins exhibit subtle, but distinct, preferences for DNA sites that contain variations of the nucleotides within the consensus motif. In addition to their modest differences in DNA binding specificities, the Hox proteins also vary in their relative affinities for DNA. Intriguingly, their relative affinities correlate with the positions of their respective genes on the hox cluster. These findings suggest that subtle differences in DNA binding specificity combined with differences in DNA binding affinity constitute features of the "Hox code" that contribute to the selective functions of Hox proteins during murine embryogenesis.

Changes of concentrations of the elements Co, Cr, Sb, and Sc in tissues of persons with joint implants

Elevated levels of Co and Cr were found in several organs of decreased implant bearers (CoCr-alloy/polyethylene joint prostheses) by means of instrumental and radiochemical neutron activation analysis as compared to normal persons. For comparative purposes, concentrations of the elements Co, Cr, Sb, and Sc were measured in heart, kidney, liver, and spleen of the patients and normal persons. For Cr determination, a new radiochemical separation technique with sufficiently low determination limit was employed. The importance of such investigations for studying possible carcinogenic effects of corrosion products and wear particles of metallic prostheses is mentioned.

Autoradiographic demonstration of glucocorticoid receptors in the intermediate lobe of the rat pituitary transplanted to the anterior eye chamber

It is a general belief that the intermediate lobe of the pituitary, in contrast to the anterior pituitary, is devoid of glucocorticoid receptors. However, Antakly et al. (1985) using immunocytochemistry, demonstrated the presence of this receptor in intermediate lobe cells deprived of the hypothalamic innervation. It was the aim of the present study to confirm this finding by auto-radiography, i.e., using an independent method. The neurointermediate lobe of adult male Wistar rats was syngeneic transplanted to the anterior eye chamber. The recipient rats were adrenalectomized 19 days after grafting and injected with [3H]corticosterone 5 days later. After a survival time of 60 min, autoradiograms were prepared by thaw-mount technique and quantitatively evaluated by silver grain counting. Beside the classical targets, anterior pituitary and hippocampal stratum pyramidale, the intraocular transplants showed a nuclear accumulation of radioactivity. This was abolished in rats treated for competition with an excess of unlabelled corticosterone prior to tracer application. No such receptor binding was found in the normotopic intermediate lobe and in the diaphragm studied as a non-target reference. Thus, this study confirmed that the glucocorticoid receptor gene is expressed if the tissue is grafted into an ectopic site.