Morphology and Dendrite-Specific Synaptic Properties of Midbrain Neurons Shape Multimodal Integration.

Multimodal integration facilitates object recognition and response to sensory cues. This depends on spatiotemporal coincidence of sensory information, recruitment of NMDA-type glutamate receptors and inhibitory feedback. Shepherd's crook neurons (SCNs) in the avian optic tectum (TeO) are an ideal model for studying cellular mechanism of multimodal integration. They receive different sensory modalities through spatially segregated dendrites, are important for stimulus selection and have an axon-carrying dendrite (AcD). We performed whole-cell patch-clamp experiments in chicken midbrain slices of both sexes. We emulated visual and auditory input in vitro by stimulating presynaptic afferents electrically. Simultaneous stimulation enhanced responses inversely depending on stimulation amplitude demonstrating the principle of inverse effectiveness. Contribution of NMDA-type glutamate receptors prolonged postsynaptic events for visual inputs only, causing a strong modality-specific difference in synaptic efficacy. We designed a multicompartment model to study the effect of morphological and physiological parameters on multimodal integration by varying the distance between soma and axonal origin and the amount of NMDA receptor (NMDAR) contribution. These parameters changed the preference of the model for one input channel and adjusted the range of input rates at which multimodal enhancement occurred on naturalistic stimulation. Thus, the unique morphology and synaptic features of SCNs shape the integration of input at different dendrites and generates an enhanced multimodal response.SIGNIFICANCE STATEMENT Multimodal integration improves perception and responses to objects. The underlying cellular mechanism depends on a balance between excitation and inhibition, and NMDA-type glutamate receptors that are involved in the multiplicative nature of enhancement following the principle of inverse effectiveness. Based on a detailed analysis of an identified multimodal cell type in the vertebrate midbrain, we studied the influence of cellular morphology and unimodal synaptic properties on multimodal integration. We can show that the combination of cellular morphology and modality-specific synaptic properties including NMDA receptor (NMDAR) contribution is optimal for nonlinear, multimodal enhancement and determines the dynamic response range of the integrating neuron. Our findings mechanistically explain how synaptic properties and cellular morphology of a midbrain neuron contribute to multimodal enhancement.

Multi-color polymer pen lithography for oligonucleotide arrays.

Multi-color patterning by polymer pen lithography (PPL) was used to fabricate covalently immobilized fluorophore and oligonucleotide arrays with up to five different components. The oligonucleotide arrays offer a virtually unlimited inventory of orthogonal binding tags for self-assembly of proteins as demonstrated by use of the arrays to monitor cell-protein interactions of MCF7 cells.

Reorganization of Synaptic Connections and Perineuronal Nets in the Deep Cerebellar Nuclei of Purkinje Cell Degeneration Mutant Mice.

The perineuronal net (PN) is a subtype of extracellular matrix appearing as a net-like structure around distinct neurons throughout the whole CNS. PNs surround the soma, proximal dendrites, and the axonal initial segment embedding synaptic terminals on the neuronal surface. Different functions of the PNs are suggested which include support of synaptic stabilization, inhibition of axonal sprouting, and control of neuronal plasticity. A number of studies provide evidence that removing PNs or PN-components results in renewed neurite growth and synaptogenesis. In a mouse model for Purkinje cell degeneration, we examined the effect of deafferentation on synaptic remodeling and modulation of PNs in the deep cerebellar nuclei. We found reduced GABAergic, enhanced glutamatergic innervations at PN-associated neurons, and altered expression of the PN-components brevican and hapln4. These data refer to a direct interaction between ECM and synapses. The altered brevican expression induced by activated astrocytes could be required for an adequate regeneration by promoting neurite growth and synaptogenesis.

Reduction of Advanced Breast Cancer Stages at Subsequent Participation in Mammography Screening.

PURPOSE: The decline in advanced breast cancer stages is presumably the most relevant surrogate parameter in mammography screening. It represents the last step in the causal cascade that is expected to affect breast cancer-related mortality. To assess the effectiveness of population-based screening, we analyzed the 2-year incidence rates of advanced breast cancers between women participating in the initial and in the first subsequent round. MATERIALS AND METHODS: The study included data from 19,563 initial and 18,034 subsequent examinations of one digital screening unit (2008 - 2010). Data on tumor stages, detected by screening or within the following interval of two years (2-year incidence), were provided by the epidemiological cancer registry. Rates of all and combined UICC stages 2, 3 and 4 (advanced stages) were reported for a two-year period. Proportions were tested for significance by using chi-square tests (p < 0.001). RESULTS: The 2-year incidence rate of all stages was significantly lower in participants in subsequent screening than in initial screening (0.85 vs. 1.29 per 100 women (%); p < 0.0001). A significantly lower 2-year incidence of advanced stages was observed for subsequent screening compared to initial screening (0.26 % vs. 0.48 %; p = 0.0007). Among women aged 50 to 59 years, the incidence of advanced stages was less clearly different (0.21 % vs. 0.35 %; p = 0.07) than in women aged 60 to 69 years (0.31 % vs. 0.70 %; p = 0.0008). CONCLUSION: During the change from prevalent to incident phase mammography screening, a program impact is seen by a lower 2-year incidence of advanced breast cancers within subsequent compared to initial participants, predominately in women aged 60 to 69 years. KEY POINTS: • The incidence of advanced tumor stages represents the most relevant surrogate parameter for screening effectiveness. • For the first time the 2-year incidence of advanced breast cancer stages after subsequent mammography screening was analyzed. • We observed a significant effect of screening on the 2-year incidence of advanced stages, predominately in the age group 60 to 69 years.

Rates of presurgical underestimation of breast cancer after standardized assessment of breast calcifications.

PURPOSE: To determine the frequency of histopathological underestimation of breast cancer after vacuum-assisted biopsy (VAB) in standardized assessment of breast calcifications compared to postsurgical diagnosis. MATERIALS AND METHODS: The retrospective study included acquired data of 506 consecutively examined women, who underwent VAB for the assessment of pure calcifications after standardized digital mammographic and sonographic imaging. 119/506 (24.5 %) women underwent further surgical procedures: 37 women had a surgical diagnostic excision biopsy, 82 women a surgical procedure based on a therapeutic concept. Presurgical results of VAB were compared with the postsurgical histopathological reports. RESULTS: In 91/119 women (76.5 %) the final histology was malignant. The rate of ductal carcinoma in situ (DCIS) was 79.1 % (72/91) and the rate of invasive carcinoma was 20.9 % (19/91). In 9/37 women with diagnostic excision biopsy, the presurgical status of benign or uncertain changed to a postsurgical diagnosis of malignant (24.3 %). In eight cases underestimation included DCIS (21.6 %) and in one case invasive cancer (2.7 %). Seven of the nine underestimated cases (77.8 %) resulted from excision biopsy of atypical epithelial proliferation of ductal type (AEPDT, positive predictive value 30.4 % (7/23)). After surgery due to DCIS in 7/71 women invasive breast cancer was diagnosed (9.9 %). In 11/82 women with oncological surgery, invasive cancer was already diagnosed by VAB. CONCLUSION: Underestimation of invasive cancer in terms of presurgical DCIS diagnosis can be minimized by the standardized assessment protocol to about 10 %. Underestimation of DCIS is mainly related to presurgical diagnosis of AEPDT. KEY POINTS: • The standardized use of digital mammographic and sonographic imaging prior to vacuum-assisted biopsy is suitable for minimizing underestimation of invasive breast cancer. AEPDT represents a high risk diagnosis for underestimation of DCIS.

Hybrid voltage sensor imaging of eGFP-F expressing neurons in chicken midbrain slices.

BACKGROUND: Dendritic computation is essential for understanding information processing in single neurons and brain circuits. Optical methods are suited best to investigate function and biophysical properties of cellular compartments at high spatial and temporal resolution. Promising approaches include the use of voltage sensitive dyes, genetically encoded voltage sensors, or hybrid voltage sensors (hVoS) consisting of fluorescent proteins and voltage-dependent quenchers that, so far, are not available in avian neuroscience. NEW METHOD: We have adapted a hVoS system for a chicken midbrain slice preparation by combining genetically expressed farnesylated eGFP with dipicrylamine (DPA). Depending on the cellular potential, DPA is shifted in the membrane, resulting in quenching of eGFP fluorescence linearly to the membrane potential by Förster resonance electron transfer. RESULTS: In ovo electroporation resulted in labelled neurons throughout the midbrain with a high level of fine structural detail. After application of DPA, we were able to optically record electrically evoked action potentials with high signal-to-noise ratio and high spatio-temporal resolution. COMPARISON WITH EXISTING METHODS: Standard methods available for avian neuroscience such as whole-cell patch clamp yield insufficient data for the analysis of dendritic computation in single neurons. The high spatial and temporal resolution of hVoS data overcomes this limitation. The results obtained by our method are comparable to hVoS data published for mammals. CONCLUSIONS: With the protocol presented here, it is possible to optically record information processing in single avian neurons at such high spatial and temporal resolution, that cellular and subcellular events can be analysed.

Aggrecan, link protein and tenascin-R are essential components of the perineuronal net to protect neurons against iron-induced oxidative stress.

In Alzheimer's disease (AD), different types of neurons and different brain areas show differential patterns of vulnerability towards neurofibrillary degeneration, which provides the basis for a highly predictive profile of disease progression throughout the brain that now is widely accepted for neuropathological staging. In previous studies we could demonstrate that in AD cortical and subcortical neurons are constantly less frequently affected by neurofibrillary degeneration if they are enwrapped by a specialized form of the hyaluronan-based extracellular matrix (ECM), the so called 'perineuronal net' (PN). PNs are basically composed of large aggregating chondroitin sulphate proteoglycans connected to a hyaluronan backbone, stabilized by link proteins and cross-linked via tenascin-R (TN-R). Under experimental conditions in mice, PN-ensheathed neurons are better protected against iron-induced neurodegeneration than neurons without PN. Still, it remains unclear whether these neuroprotective effects are directly mediated by the PNs or are associated with some other mechanism in these neurons unrelated to PNs. To identify molecular components that essentially mediate the neuroprotective aspect on PN-ensheathed neurons, we comparatively analysed neuronal degeneration induced by a single injection of FeCl3 on four different mice knockout strains, each being deficient for a different component of PNs. Aggrecan, link protein and TN-R were identified to be essential for the neuroprotective properties of PN, whereas the contribution of brevican was negligible. Our findings indicate that the protection of PN-ensheathed neurons is directly mediated by the net structure and that both the high negative charge and the correct interaction of net components are essential for their neuroprotective function.

Validation of methods for the detection and quantification of engineered nanoparticles in food.

The potential impact of nanomaterials on the environment and on human health has already triggered legislation requiring labelling of products containing nanoparticles. However, so far, no validated analytical methods for the implementation of this legislation exist. This paper outlines a generic approach for the validation of methods for detection and quantification of nanoparticles in food samples. It proposes validation of identity, selectivity, precision, working range, limit of detection and robustness, bearing in mind that each "result" must include information about the chemical identity, particle size and mass or particle number concentration. This has an impact on testing for selectivity and trueness, which also must take these aspects into consideration. Selectivity must not only be tested against matrix constituents and other nanoparticles, but it shall also be tested whether the methods apply equally well to particles of different suppliers. In trueness testing, information whether the particle size distribution has changed during analysis is required. Results are largely expected to follow normal distributions due to the expected high number of particles. An approach of estimating measurement uncertainties from the validation data is given.

Minimal invasive biopsy results of "uncertain malignant potential" in digital mammography screening: high prevalence but also high predictive value for malignancy.

PURPOSE: To evaluate the rate, the histological spectrum and the positive predictive value (PPV) for malignancy of minimally invasive biopsies with "uncertain malignant potential (B3)" in digital mammography screening. METHODS AND MATERIALS: Consecutive data of 37,178 participants of one digital unit of the German screening program were included. RESULTS: The B 3 rate was 15.1 % (148 / 979). The frequencies of lesion subtypes were as follows: atypical epithelial proliferation of ductal type (AEPDT) 35.1 % (52 / 148), radial scar (RS) 28.4 % (42 / 148), papillary lesions (PAP) 20.3 % (30 / 148), lobular carcinoma in situ 8.8 % (13 / 148), flat epithelial atypia 5.4 % (8 / 148), and mucocele-like lesions 2.0 % (3 / 148). The PPV for malignancy in surgical excisions was overall 0.28 (25 / 91); in detail 0.40 (19 / 47) for AEPDT, 0.20 (5 / 25) for RS, 0.08 (1 / 12) for PAP. CONCLUSION: Despite a higher B 3 rate of minimally invasive biopsies with "uncertain malignant potential" in digital screening, the benign surgical biopsy rate is not disproportionally increased compared with analog screening programs. Together with defined management protocols, this results in an increased cancer detection rate per screening participant with surgical excision.

First epidemiological analysis of breast cancer incidence and tumor characteristics after implementation of population-based digital mammography screening.

PURPOSE: To epidemiologically evaluate the impact of digital mammography screening on incidence rates and tumor characteristics for breast cancer. MATERIALS AND METHODS: The first German digital screening units in the clinical routine were evaluated during the implementation period by using data from the cancer registry to compare the incidence rate of breast cancers and prognostic characteristics. 74 % of women aged 50 - 69 within the region of Muenster/Coesfeld/Warendorf were invited between 10 / 2005 and 12 / 2007 for initial screening; 55 % participated (n = 35 961). RESULTS: In 2002 - 2004 the average breast cancer incidence rate (per 100,000) was 297.9. During the implementation of screening, the rate rose to 532.9 in 2007. Of the 349 cancers detected with screening, 76 % (265 / 349) were invasive compared to 90 % (546 / 608) of cases not detected with screening during the same period. 37 % (97 / 265) of cancers detected in the screening program had a diameter of

[Immunohistochemistry in breast pathology: differential diagnosis of epithelial breast lesions]. / Immunhistochemie in der Mammapathologie: Zur Differenzialdiagnose epithelialer Mammaläsionen.

Proliferative epithelial breast lesions include a wide variety of benign hyperplastic and noninvasive neoplastic lesions, as well as invasive carcinomas. Mammographically these lesions may show microcalcifications, architectural distortions or mass lesions. The task of the pathologist begins with a preoperative diagnosis by means of minimally invasive biopsy. His diagnosis forms the basis for not only the radiological-pathological correlation diagnosis, but also for the management of benign proliferative breast disease lesions, as well as therapeutic decisions in the case of malignant lesions.In daily practice, immunohistochemistry is the method of choice for clarifying difficult cases. The aim of this chapter is to describe the relevant markers in breast pathology and to provide an algorithmic approach to different proliferative breast disease lesions.

[Diagnostics of microcalcifications from minimally invasive biopsies in mammography screening: results from the prevalence phase]. / Mikrokalkdiagnostik an minimal-invasiven Biopsien im Mammographie-Screening: Ergebnisse aus der Prävalenzphase.

BACKGROUND: In mammography screening programmes carried out according to European guidelines, minimally invasive biopsies (MIB) are performed on up to 3% of participants. The aim of this study was to analyse the spectrum of histopathological findings including B categories in MIBs with microcalcifications compared to MIBs without microcalcifications. MATERIAL AND METHODS: Prospectively collected histological findings of MIBs taken during the period July 2006 to June 2007 were analysed using the Breast Screening Pathology Database of the Reference Centre in Münster. RESULTS: Of the 4,326 MIBs investigated, 2,161 were benign (B1-B3) whereas 2,165 were malignant (B4-B5) resulting in an overall malignancy rate of 50.04%. Of the MIBs 1,809 contained microcalcifications and 2,517 did not. Cases with microcalcifications showed a different distribution of B categories: B2 was found in 44.5% versus 24.2%, B3 in 18.2% versus 5.5% and the malignancy rate of cases with microcalcifications was 36.8% versus 59.5%. Of all cases of ductal carcinoma in situ (DCIS) detected in the screening programme, 83.35% were diagnosed in MIBs containing microcalcifications. CONCLUSIONS: MIBs containing microcalcifications showed a different spectrum of diagnoses, especially higher rates of B3 lesions. Even though MIBs without microcalcifications showed a higher overall malignancy rate, most cases of DCIS were diagnosed in MIB containing microcalcifications.

[Atypical ductal hyperplasia and atypical epithelial proliferation of ductal type]. / Atypische duktale Hyperplasie und atypische epitheliale Proliferation vom duktalen Typ.

The definition of atypical ductal hyperplasia (ADH) encompasses qualitative and quantitative criteria. Qualitative criteria include cytological and architectural features similar to those of low grade ductal carcinoma in situ (DCIS), the quantitative criteria are characterized by metric features (2 mm or 2 ductules) or by the confines of lobules. In this article we discuss the morphology of ADH, the status of ADH in the low grade pathway of breast carcinoma development and its clinical significance. Furthermore, we comment some special forms of atypical epithelial proliferations of the ductal type.

[Flat epithelial atypia]. / Flache epitheliale Atypie.

According to the WHO, flat epithelial atypia (FEA) is defined as a neoplastic epithelial proliferation of ductal type in either a single or in multiple terminal duct lobular unit(s) limited to the periphery of the ductules in a clinging growth pattern. The atypical cells may form between one and several layers of epithelial cells that show low grade cytologic atypia. FEA most often presents as mammographic microcalcifications, which are typically round (secretory type and psammomatous calcification in an eosinophilic matrix, so-called ossifying calcifications). Clinical relevance is dependent on whether the lesion appears in isolation or whether it is an excision biopsy or a minimally invasive biopsy. Currently available data suggest that the risk of subsequent breast carcinoma in the ipsilateral breast is very low following the diagnosis of FEA. The differential diagnosis should include atypical ductal hyperplasia, low-grade clinging ductal carcinoma in situ, blunt duct adenosis and apocrine metaplasia.

Validation of an optical surface plasmon resonance biosensor assay for screening (fluoro)quinolones in egg, fish and poultry.

A surface plasmon resonance biosensor immunoassay has been developed for multi-residue determination of 13 (fluoro)quinolone antibiotics in poultry meat, eggs and fish. The following performance characteristics were determined according to the guidelines laid down for screening assay validation in European Decision 2002/657/EC: detection capability, specificity/selectivity, decision limit, repeatability, ruggedness and stability. The detection capability estimated for norfloxacin, the reference fluoroquinolone, was below 0.5, 1 and 1.5 ng g⁻¹ for poultry meat, egg and fish, respectively. The screening assay proved specific and showed satisfactory sensitivity below the MRL levels even though flumequine and oxolinic acid had lower cross-reactivities. A wide range of non-MRL substances were also detected at concentrations below 10 ng g⁻¹. Repeatability was good with both intra- and inter-assay coefficients of variation 56%; ruggedness was also demonstrated.

Development of an optical surface plasmon resonance biosensor assay for (fluoro)quinolones in egg, fish, and poultry meat.

The aim of this study was to develop an optical biosensor inhibition immunoassay, based on the surface plasmon resonance (SPR) principle, for use as a screening test for 13 (fluoro)quinolones, including flumequine, used as veterinary drugs in food-producing animals. For this, we immobilised various quinolone derivatives on the sensor chip and tested binding of a range of different antibodies (polyclonal and one engineered antibody) in the presence and absence of free (fluoro)quinolones. The main challenge was to detect flumequine in an assay giving good results for the other compounds. One antigen-antibody combination proved satisfactory: polyclonal antibodies raised against a dual immunogen and, on the sensor chip, a fluoroquinolone derivative. It was the first time that this concept of the bi-active antibody was described in the literature. The assay, optimised for detection in three matrices (poultry muscle, fish, and egg), was tested on incurred samples prepared by liquid extraction followed by two washing steps. This rapid, simple method proved adequate for detecting at least 13 (fluoro)quinolones at concentrations below established maximum residue levels (MRLs). The reference molecule norfloxacin could be detected in the range of 0.1-10 microg kg(-1) in extracts of egg and poultry meat and in the range of 0.1-100 microg kg(-1) in extracts of fish. The determined midpoints of these calibration curves were about 1, 1.5 and 3 microg kg(-1) in poultry meat, egg and fish, respectively.

Digital mammography screening: average glandular dose and first performance parameters.

PURPOSE: The Radiation Protection Commission demanded structured implementation of digital mammography screening in Germany. The main requirements were the installation of digital reference centers and separate evaluation of the fully digitized screening units. Digital mammography screening must meet the quality standards of the European guidelines and must be compared to analog screening results. We analyzed early surrogate indicators of effective screening and dosage levels for the first German digital screening unit in a routine setting after the first half of the initial screening round. MATERIALS AND METHODS: We used three digital mammography screening units (one full-field digital scanner [DR] and two computed radiography systems [CR]). Each system has been proven to fulfill the requirements of the National and European guidelines. The radiation exposure levels, the medical workflow and the histological results were documented in a central electronic screening record. RESULTS: In the first year 11,413 women were screened (participation rate 57.5 %). The parenchymal dosages for the three mammographic X-ray systems, averaged for the different breast sizes, were 0.7 (DR), 1.3 (CR), 1.5 (CR) mGy. 7 % of the screened women needed to undergo further examinations. The total number of screen-detected cancers was 129 (detection rate 1.1 %). 21 % of the carcinomas were classified as ductal carcinomas in situ, 40 % of the invasive carcinomas had a histological size

Maintenance immunotherapy by repetitive low-dose donor lymphocytes infusions in a child with relapse state aml after allogeneic stem cell transplantation.

The treatment of a child with a relapsed state acute leukemia after allogeneic stem cell transplantation (allo-SCT) is a challenge. The authors report about a child with an acute myelogenous leukemia (AML), which relapsed after allo-SCT despite immunological intervention. It was further treated with a second line chemotherapy followed by an infusion of stem cells and donor lymphocytes. Because of an immense risk for a further relapse, an immunological maintenance therapy was also performed, consisting of repetitive infusions of low doses of donor lymphocytes combined with low-dose chemotherapy. Presently, the child is in continuous complete remission and has a good quality of life.

Androgen-binding protein is co-expressed with oxytocin in the male reproductive tract.

Androgen-binding protein (ABP) and the posterior lobe hormone oxytocin (OT) were co-localized in male rat reproductive organs. Immunostaining of serial semi-thin sections revealed a high rate of coexistence of both antigens in Sertoli cells and in the epithelial cells of the prostate. There was a considerably less co-localization of OT and ABP in epithelial cells of the epididymis, and in the different tissues of the ductus deferens. In situ hybridization with synthetic oligonucleotides complementary to a fragment of ABP mRNA showed specific staining in the same sites that were immunostained for ABP. ABP was isolated by affinity chromatography from homogenates of testis, epididymis, prostate and the content of the prostate lumen. Identical protein patterns could be shown with surface-enhanced laser desorption/ionization time-of-flight mass spectrometry in all samples except for the epididymis indicating that ABP structure is similar in all these tissues. ABP seems to be expressed in specified cells throughout the male rat reproductive tract. Most of these cells appear to be oxytocinergic. ABP and OT have previously been detected in the ejaculate. The observed epithelial cells are likely to be their source.