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Objectives. The retinoblastoma (RB) pathway is crucial in the development and progression of many cancers. To better understand the biology of progressive breast cancer (BC), we examined protein expression of the RB pathway in primary BCs and matched axillary lymph node metastases (LM). Methods. Immunohistochemistry was used to evaluate cyclin D1, CDK4/6, RB, phosphorylated RB (pRB), and E2F1 expression in tissue arrays containing cores of 50 primary BCs and matched LM. The number of positive tumor cells and staining intensity were scored. Results. The proteins were localized in the nucleus, while CDK6 was detected in the cytoplasm and CDK4 was found in both. pRB and E2F1 showed higher expression in matched LM than in primary tumors. Expression of these proteins differed significantly by the percentage of positive tumor cells, while proteins in the proximal portion of the RB pathway showed no significant differences. The main path of alteration consisted of high pRB in primary BC, remaining pRB high in the majority of LM, variations occurring in fewer cases. All matched LM of the few primary tumors that had unaltered RB and pRB expression showed changes in RB or pRB expression. Conclusion. Expression of pRB and E2F1 was significantly higher in LM than in primary BC. A majority of cancers with LM showed altered RB or pRB expression, suggesting that proteins downstream in the RB pathway play a critical role in metastatic BC and disease progression. So looking at the RB pathway could be an option for chemotherapy decisions in patients with only few LM.

PDF file - 863K, Western blots of ectopically expressed BRCA2 wildtype and VUS containing proteins

PDF file - 58K, Table showing model-based estimates of conditional probabilities in favor or against pathogenicity for VUS based on HDR activity calculated with equal prior probabilities or AGVGD-based prior probabilities for each variant

PDF file - 66K, Table showing the normalized mean HDR assay fold-change and log transformed values for each VUS

PDF file - 3.9MB, Location of the non-pathogenic and intermediate variants in the mouse BRCA2-DSS1-ssDNA complex

PDF file - 42K

We assessed the PREDICT v 2.2 for prognosis of breast cancer patients with pathogenic germline BRCA1 and BRCA2 variants, using follow-up data from 5453 BRCA1/2 carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) and the Breast Cancer Association Consortium (BCAC). PREDICT for estrogen receptor (ER)-negative breast cancer had modest discrimination for BRCA1 carrier patients overall (Gönen & Heller unbiased concordance 0.65 in CIMBA, 0.64 in BCAC), but it distinguished clearly the high-mortality group from lower risk categories. In an analysis of low to high risk categories by PREDICT score percentiles, the observed mortality was consistently lower than the expected mortality, but the confidence intervals always included the calibration slope. Altogether, our results encourage the use of the PREDICT ER-negative model in management of breast cancer patients with germline BRCA1 variants. For the PREDICT ER-positive model, the discrimination was slightly lower in BRCA2 variant carriers (concordance 0.60 in CIMBA, 0.65 in BCAC). Especially, inclusion of the tumor grade distorted the prognostic estimates. The breast cancer mortality of BRCA2 carriers was under-estimated at the low end of the PREDICT score distribution, whereas at the high end, the mortality was over-estimated. These data suggest that BRCA2 status should also be taken into consideration with tumor characteristics, when estimating the prognosis of ER-positive breast cancer patients.

Postoperative wound-site bleeding, tissue inflammation and seroma formation are well-known complications in the field of breast surgery. Hemostatic agents consisting of polysaccharides may be used intra-operatively to minimise postoperative complications. We conducted a prospective randomised-controlled, single-centre study including 136 patients undergoing breast-conserving surgery for invasive or intraductal breast cancer. Of these, 68 patients were randomised to receive an absorbable polysaccharide hemostatic agent into the wound site during surgery, while 68 patients were randomised to the control group and did not receive any hemostatic agent. Primary outcome was the total volume of postoperative drained fluid from the surgical site. Secondary outcomes were the number of days until drain removal and rate of immediate postoperative surgical site infection Patients in the intervention group had significantly higher drainage output volumes compared with the control group 85 mL (IQR 46.25-110) versus 50 mL (IQR 30-75), respectively; (P = .003). Univariable linear regression analyses showed a significant association between the surgical specimen and the primary outcome (P .001). After multivariable analysis, the use of absorbable polysaccharide hemostatic product was no longer significantly associated with a higher drainage output and only the size of the surgical specimen remained a significant predictor. The number of days until drainage removal and the postoperative seroma formation were higher in the intervention group (P = .004) and (P = .003), respectively. In our study, intraoperative application of polysaccharide hemostatic agent during breast-conserving surgery did not decrease postoperative fluid production. Only the size of the surgical specimen was significantly associated with postoperative drainage volume.

SummaryIn the past 12 months a plethora of relevant novel data for the treatment of metastatic HER2 positive breast cancer were published. To bring this new evidence into a clinical perspective, a group of Austrian breast cancer specialists updated their previously published treatment algorithm for those patients. For this consensus paper a total of eight scenarios were developed in which treatment strategies appropriate for specific patient profiles were evaluated. Consensus was established by detailed discussions of each scenario and by reaching full consensus.

Catalysts 12(6), 675 (2022). doi:10.3390/catal12060675, The replacement of noble metal catalysts by abundant iron as an active compound in CO oxidation is of ecologic and economic interest. However, improvement of their catalytic performance to the same level as state-of-the-art noble metal catalysts requires an in depth understanding of their working principle on an atomic level. As a contribution to this aim, a series of iron oxide catalysts with varying Fe loadings from 1 to 20 wt% immobilized on a γ-Al2O3 support is presented here, and a multidimensional structure–activity correlation is established. The CO oxidation activity is correlated to structural details obtained by various spectroscopic, diffraction, and microscopic methods, such as PXRD, PDF analysis, DRUVS, Mössbauer spectroscopy, STEM-EDX, and XAS. Low Fe loadings lead to less agglomerated but high percentual amounts of isolated, tetrahedrally coordinated iron oxide species, while the absolute amount of isolated species reaches its maximum at high Fe loadings. Consequently, the highest CO oxidation activity in terms of turnover frequencies can be correlated to small, finely dispersed iron oxide species with a large amount of tetrahedrally oxygen coordinated iron sites, while the overall amount of isolated iron oxide species correlates with a lower light-off temperature., Published by MDPI, Basel

Oncoplastic techniques allow resection of larger tumors, permitting breast conservation in cases otherwise requiring mastectomy. We sought to prospectively compare quality of life (QoL) in patients undergoing oncoplastic surgery as compared to conventional breast conservation (CBC) or mastectomy is lacking.Patients diagnosed with BIRADS IV-VI lesion were eligible if resection of ≥10% of the breast volume was planned. Patients were allowed to decide whether they wanted to undergo CBC or oncoplastic breast conservation (OBC). Patients who underwent mastectomy and immediate breast reconstruction (IBR) were also included for comparison. The primary endpoint was breast self-esteem using the Breast Image Scale (BIS) at 12 months, secondary endpoints were perioperative morbidity and QoL using the BREAST-Q questionnaire.From 2011 to 2016, 205 patients were included in the study. 116 patients (56.6%) received CBC, 46 (22.4%) OBC and 43 (21%) MIBR. Women in the OBC group were more likely to have tumors ≥ 2 cm than those in the CBC group (34.7% vs. 17.5%, respectively). Women who underwent MIBR were more likely to have tumors5 cm than those in the CBC and OBC groups (23% vs 1% and 10%, respectively). The BIS and BREAST-Q improved in each group after 12 months but did not differ significantly between groups at any time point. Surgical complications (seroma, bleeding, infection, necrosis) were numerically more likely in the OBC and MIBR groups.OBC and the MIBR allow for resection of larger tumors with a similar quality of life as CBC.

Neoadjuvant chemotherapy (NAC) in combination with anti-HER2 treatment is standard of care in patients with early HER2 positive breast cancer. Preoperative radiological evaluation is mandatory for defining the extent of surgery. In this study, we evaluated the correlation between preoperative radiological and postoperative pathological tumor size in early HER2 positive patients after neoadjuvant chemotherapy in combination with trastuzumab and pertuzumab. In a patient population with HER2 positive breast cancer, who received neoadjuvant chemotherapy and anti-HER2 treatment, the correlation between preoperative radiological and postoperative pathological tumor size was performed. Concordance of radiological and pathological tumor size was found in 55.7%, leading to more extensive breast surgery as required in 7 cases and to the underestimation of 6 neoplastic lesions before surgery, respectively.Seventy early HER2 positive breast cancer patients were included and retrospectively analysed. All preoperative radiological assessments as well as the tumor board decision on surgical extent and pathological evaluation were completed at the Medical University of Vienna. Preoperative radiological assessment of tumor size and lymph node status were compared with final histopathological findings. The correlation between different radiological modalities regarding tumor size was investigated.Concordance of radiological and pathological tumor size was found in 55.7 % (50% by sonography and 66.7% by MRI, respectively) of patients with a nonsignificant correlation of r = 0.31 (P = .08). Of the 39 patients with pathologic complete remission (pCR), 16 were also classified as radiological complete response (rCR) while 23 of those showed a radiological stable disease or partial response. In 6 patients, radiological assessment showed a CR but invasive cancer with a tumor size range from 7 to 36 mm was found in histopathological examination. Neither menopausal status (P= .69) nor BMI (P = .60) and age (P = .50) had an impact on the correlation between radiological and histopathological tumor size. Regarding lymph node status, a statistically significant association and clinically relevant correlation between radiological and histopathological evaluation was found (r = 0.66, P.001).Concordance between radiology and histopathology was low regarding tumor size after NAC in combination with trastuzumab and pertuzumab, but significant regarding lymph node status.

In December 2017, ESMO Open—Cancer Horizons convened a round-table discussion on the background and latest data regarding cyclin-dependent kinase (CDK)4/6 inhibitors with endocrine therapy (ET) in the treatment of endocrine-sensitive breast cancer (BC). A review on this discussion was published in summer 2018 (https://esmoopen.bmj.com/content/3/5/e000368).Endocrine-sensitive BC with non-visceral disease and limited spread of the metastases.Endocrine-sensitive BC with non-life-threatening visceral involvement. Several open questions were identified, which led to a second ESMO Open discussion on CDK4/6 inhibitors, taking place in December 2018 and covered in this article. The panel discussed two important clinical scenarios and the pro and cons of a treatment approach with CDK4/6 inhibitors for each scenario:Endocrine-sensitive BC with non-visceral disease and limited spread of the metastases.Endocrine-sensitive BC with non-life-threatening visceral involvement. Regarding scenario 1, the panel agreed that CDK4/6 inhibitors should be recommended in first-line therapy for most patients if cost and practicality allow. However, the use of single-agent ET with an aromatase inhibitor in the first-line treatment of these patients is still a possibility for a small group of patients with very limited disease, such as one or two bone lesions or limited lymph node involvement. Regarding scenario 2, chemotherapy is the first approach for patients with endocrine-sensitive metastatic BC with life-threatening visceral involvement because of the need for a faster response. The therapeutic approaches for patients with non-life-threatening visceral involvement are still under debate. Nevertheless, CDK4/6 inhibitors are currently the treatment of choice for most patients with a close follow-up of tumour response. A treatment algorithm has been suggested at the round table.

Conflicting evidence exists regarding the value of surgical resection of the primary in stage IV breast cancer patients.The prospective randomized phase III ABCSG-28 POSYTIVE trial evaluated median survival comparing primary surgery followed by systemic therapy to primary systemic therapy in de novo stage IV breast cancer.Between 2011 and 2015, 90 previously untreated stage IV breast cancer patients were randomly assigned to surgical resection of the primary tumor followed by systemic therapy (Arm A) or primary systemic therapy (Arm B) in Austria. Overall survival (OS) was defined as the primary study endpoint.The trial was stopped early due to poor recruitment. Ninety patients (45 arm A, 45 arm B) were included; median follow-up was 37.5 months. Patients in the surgery arm had more cT3 breast cancer (22.2% vs 6.7%) and more cN2 staging (15.6% vs 4.4%). Both groups were well balanced with respect to the type of first-line systemic treatment. Median survival in arm A was 34.6 months, versus 54.8 months in the nonsurgery arm [hazard ratio (HR) 0.691, 95% confidence interval (95% CI) 0.358-1.333; P = 0.267]; time to distant progression was 13.9 months in the surgery arm and 29.0 months in the nonsurgery arm (HR 0.598, 95% CI 0.343-1.043; P = 0.0668).The prospective phase III trial ABCSG-28 (POSYTIVE) could not demonstrate an OS benefit for surgical resection of the primary in breast cancer patients presenting with de novo stage IV disease.

Background Pertuzumab combined with trastuzumab and docetaxel is the standard first-line therapy for HER2-positive metastatic breast cancer, based on results from the phase III CLEOPATRA trial. PERUSE was designed to assess the safety and efficacy of investigator-selected taxane with pertuzumab and trastuzumab in this setting. Patients and methods In the ongoing multicentre single-arm phase IIIb PERUSE study, patients with inoperable HER2-positive advanced breast cancer (locally recurrent/metastatic) (LR/MBC) and no prior systemic therapy for LR/MBC (except endocrine therapy) received docetaxel, paclitaxel or nab-paclitaxel with trastuzumab [8mg/kg loading dose, then 6mg/kg every 3weeks (q3w)] and pertuzumab (840mg loading dose, then 420mg q3w) until disease progression or unacceptable toxicity. The primary end point was safety. Secondary end points included overall response rate (ORR) and progression-free survival (PFS). Results Overall, 1436 patients received at least one treatment dose (initially docetaxel in 775 patients, paclitaxel in 589, nab-paclitaxel in 65; 7 discontinued before starting taxane). Median age was 54years; 29% had received prior trastuzumab. Median treatment duration was 16months for pertuzumab and trastuzumab and 4months for taxane. Compared with docetaxel-containing therapy, paclitaxel-containing therapy was associated with more neuropathy (all-grade peripheral neuropathy 31% versus 16%) but less febrile neutropenia (1% versus 11%) and mucositis (14% versus 25%). At this preliminary analysis (52 months' median follow-up), median PFS was 20.6 [95% confidence interval (CI) 18.9–22.7] months overall (19.6, 23.0 and 18.1months with docetaxel, paclitaxel and nab-paclitaxel, respectively). ORR was 80% (95% CI 78%–82%) overall (docetaxel 79%, paclitaxel 83%, nab-paclitaxel 77%). Conclusions Preliminary findings from PERUSE suggest that the safety and efficacy of first-line pertuzumab, trastuzumab and taxane for HER2-positive LR/MBC are consistent with results from CLEOPATRA. Paclitaxel appears to be a valid alternative taxane backbone to docetaxel, offering similar PFS and ORR with a predictable safety profile. ClinicalTrials.gov NCT01572038.

A Mn2O3 catalyst prepared by flame spray pyrolysis was physico-chemically characterized and tested for the oxidation of soot in diesel model exhaust. A special focus lay on the effect of O2 on the kinetics and local temperatures. The catalyst was tightly mixed with model soot Printex U and was evaluated by temperature programmed oxidation. The catalytic tests showed significant temperature gradients inside the Mn2O3/soot bed already at low O2 proportions (1 vol.%), whereas hot spots appeared at 5 vol.% O2 and above strongly affecting local oxidation rates. Furthermore, kinetic studies were carried out with diluted catalyst/soot mixtures providing homogenous temperature distribution. Based on these results, a global kinetic model was constructed inferring the evolution of the surface area of the soot, the number of reactive carbon sites and the reaction order of soot and O2. Finally, the kinetic model was validated by prediction of experimental data.

This paper, “Aluminium telescope for FIRST," was presented as part of International Conference on Space Optics—ICSO 1997, held in Toulouse, France.

Background A multicenter phase II study was conducted to analyze the clinical activity of the steroidal aromatase inhibitor exemestane in the neoadjuvant treatment of post-menopausal women with strongly ER- and/or PgR- positive operable breast cancer. Patients and methods From September 2000 to December 2003, 80 women were recruited for treatment with exemestane 25 mg once daily for 4 months. The primary end-point was the clinical response rate according the WHO criteria; the secondary end-points included toxicity and the number of patients who qualified for breast conserving surgery at the end of treatment, comparability of evaluation methods for response, potential alterations of hormone receptor and Her2/neu status during treatment. Results On an intention to evaluate analysis, according to the prespecified criteria the overall clinical objective response rate was 34%, the pCR rate was 3% and the rate of breast conserving surgery was 76%. When sonographic and mammographic longitudinal measurements were included in patients with missing palpation data, response rates were 38% and 41%, respectively. The tumor response was independent of the Her2/neu status which remained unchanged during treatment. In contrast, while the ER expression remained unaltered, downregulation of the PgR was observed. The treatment was well tolerated with no grade 3 and 4 toxicities except gastrointestinal (one grade 3 case) and hot flushes (two grade 3 cases). Conclusion This study shows that exemestane is effective and safe as a preoperative therapy in post-menopausal patients with strongly hormone receptor-positive breast cancer.

Special focus and aim of our research activities at AIT, the Austrian Institute of Technology, is to define reliable biomarkers suitable for early and non-invasive disease diagnosis from body fluids such as serum/plasma and saliva. Along a selection of research projects, which are described in more detail underneath, we will present and introduce the broad portfolio of high throughput technologies we successfully apply for diagnostic biomarker discovery and validation. As a first show case of successful non-invasive disease biomarker discovery we will present a study where we investigated and compared the genome wide methylation levels of lung cancer patients, patients suffering from lung fibrosis, patients with COPD (chronic obstructive pulmonary disease), and DNA samples derived from healthy lungs. Along this study we could identify specific methylation patterns for each of these lung diseases. After quantitative PCR validation of 240 disease specific methylation markers in the discovery sample set, the 90 top markers were picked and applied for serum testing (n=204). When we applied gradient boosting classification for differential diagnosis of tested lung diseases and healthy controls an AUC value of 0.95 was reached here to separate cancer from all other non-cancer samples whereas in differential diagnosis of healthy-, COPD and fibrosis patients AUC values of 0.71 and 0.49 were obtained for fibrosis, respectively COPD. Thus in case of COPD the presented method may be used to monitor cancer risk within COPD patients. Our second show case comprises a study where we screened cancer patients’ sera for tumor-specific antibody profiles using an in-house developed 16k protein-microarray. This methodology, which will be described in detail, enabled us to define different tumor-associated antigen (TAA) classifier panels for the big 4 cancer entities (breast, colon, prostate and lung cancer) which all showed very promising classification successes in distinction of patients versus controls. We will further present preliminary data obtained when comparing serum and saliva autoantibody profiles of breast-cancer patients and healthy controls.

BRCA mutation carriers are at high risk of developing ovarian cancer. Ovarian malignancies are usually identified at an advanced stage with poor prognosis, attributed to inadequate options of early detection. Because of its risk-reducing effect of nearly 96%, prophylactic salpingo-oophorectomy is still the leading option for risk-reduction in women with a positive BRCA mutation status. The presence of ovarian cancer precursor lesions, such as epithelial inclusion cysts (EICs) or cortical invaginations (CIs), has previously been discussed in several studies with diverse conclusions. We retrospectively investigated a large and consistent population (n=94) of BRCA mutation carriers for the presence of potential preneoplastic and neoplastic changes. We also examined the role of specific lifestyle factors. Ninety-four women with disease-associated germline BRCA1 or BRCA2 mutations were included in this retrospective study. All women had undergone genetic counseling and prophylactic salpingo-oophorectomy, which was performed at a mean age of 43.33 years (range 27-66). Histological slides of both ovaries were reviewed by an independent pathologist. Data concerning lifestyle factors were collected from medical files and questionnaires. Two malignant lesions (2.1%), one bilateral serous papillary adenocarcinoma of the epithelial surface and one adenocarcinoma of the peritoneum with involvement of the left adnexa, and one lesion (1.1%) with obvious malignant potential, one mucinous borderline tumor of the right ovary, have been identified. We registered a high prevalence of CIs (30; 31.9%) and EICs (44; 46.8%) in prophylactically removed ovaries of BRCA mutation carriers. A significant correlation (P=0.002) was found with regard to the presence of EICs in women with increased BMI. Concerning the regular consumption of alcohol as a risk factor for premalignant lesions, in particular CIs, a statistically insignificant trend (P=0.083) was noted. Overweight women seem to be at risk of developing more cortical invaginations than women of normal weight. To improve the final outcome of the disease, women at increased risk of ovarian cancer should be appropriately informed of potential increased risk factors.

The insulin-like growth factors (IGFs) are mitogens for many cancer cell types. In breast cancer cells, IGF-I and IGF-II have both been shown to stimulate cell proliferation. However, IGF-I mRNA has not been found in human breast cancer cell lines, making it unlikely that IGF-I is commonly expressed as an autocrine growth factor for breast cancer cells. Nevertheless, IGF-I mRNA can be detected in breast cancer tissue samples, and in situ hybridization studies have shown that the message originates from the stromal cells adjacent to normal lobules. IGF-II, on the other hand, has been detected in some breast cancer cell lines. In the estrogen receptor positive cell line T47-D, IGF-II mRNA was induced by estradiol. Furthermore, transfection of an IGF-II expression vector into a previously estrogen-dependent cell line resulted in hormone independent growth. Thus, IGF-II can be expressed as an autocrine growth factor in some breast cancers and its expression may, in part, result in hormone independence. Finally, stromal cells obtained from breast tissues showed that IGF-I was commonly expressed in fibroblasts derived from non-malignant biopsy specimens, while IGF-II mRNA was detected in fibroblasts adjacent to malignant tissue. These studies suggest that IGF-II expression may be important in both autocrine and paracrine regulation of breast cancer cell growth.

Purpose: The objective of our study was to determine the clinical relevance of cyclin D1 expression in hormone receptor–positive breast cancer patients who were treated with tamoxifen-based therapy. Experimental Design: We assessed expression of cyclin D1 in surgical specimens of breast carcinoma by means of immunohistochemistry. Patients had been enrolled in either Austrian Breast and Colorectal Cancer Study Group (ABCSG) Trial 05 or ABCSG Trial 06 and received tamoxifen as part of their adjuvant treatment. Overall survival and relapse-free survival were analyzed with Cox models adjusted for clinical and pathologic factors. Results: Cyclin D1 was expressed in 140 of 253 (55%) tumors of ABCSG Trial 05 and in 569 of 948 (60%) tumors of ABCSG Trial 06. Expression of cyclin D1 was associated with poor outcome in both cohorts. Overall survival was significantly shorter in patients with cyclin D1–positive tumors compared with patients with cyclin D1–negative tumors [adjusted hazard ratio (HR) for death (ABCSG Trial 05), 2.47; 95% confidence interval (95% CI), 1.08-5.63; P = 0.03; adjusted HR for death (ABCSG Trial 06), 1.78; 95% CI, 1.36-2.34; P < 0.0001]. Relapse-free survival was also shorter in patients with cyclin D1–positive tumors than in patients with cyclin D1–negative tumors [adjusted HR for relapse (ABCSG Trial 05), 2.73; 95% CI, 1.50-4.96; P = 0.001; adjusted HR for relapse (ABCSG Trial 06), 1.52; 95% CI, 1.14-2.04; P = 0.005]. Conclusion: Cyclin D1 expression is an independent poor prognostic factor in women with early-stage, hormone receptor–positive breast cancer who received adjuvant tamoxifen-based therapy.

Fast and reliable identification of microbial isolates is a fundamental goal of clinical microbiology. However, in the case of some fastidious gram-negative bacterial species, classical phenotype identification based on either metabolic, enzymatic, or serological methods is difficult, time-consuming, and/or inadequate. 16S or 23S ribosomal DNA (rDNA) bacterial sequencing will most often result in accurate speciation of isolates. Therefore, the objective of this study was to find a hypervariable rDNA stretch, flanked by strongly conserved regions, which is suitable for molecular species identification of members of the Neisseriaceae and Moraxellaceae . The inter- and intrageneric relationships were investigated using comparative sequence analysis of PCR-amplified partial 16S and 23S rDNAs from a total of 94 strains. When compared to the type species of the genera Acinetobacter, Moraxella , and Neisseria , an average of 30 polymorphic positions was observed within the partial 16S rDNA investigated (corresponding to Escherichia coli positions 54 to 510) for each species and an average of 11 polymorphic positions was observed within the 202 nucleotides of the 23S rDNA gene (positions 1400 to 1600). Neisseria macacae and Neisseria mucosa subsp. mucosa (ATCC 19696) had identical 16S and 23S rDNA sequences. Species clusters were heterogeneous in both genes in the case of Acinetobacter lwoffii, Moraxella lacunata , and N. mucosa. Neisseria meningitidis isolates failed to cluster only in the 23S rDNA subset. Our data showed that the 16S rDNA region is more suitable than the partial 23S rDNA for the molecular diagnosis of Neisseriaceae and Moraxellaceae and that a reference database should include more than one strain of each species. All sequence chromatograms and taxonomic and disease-related information are available as part of our ribosomal differentiation of medical microorganisms (RIDOM) web-based service ( http://www.ridom.hygiene.uni-wuerzburg.de/ ). Users can submit a sequence and conduct a similarity search against the RIDOM reference database for microbial identification purposes.

Reliable identification of micro-organisms often requires several techniques, such as morphology and nutritional physiology. These methods are time consuming and can be ambiguous. With the use of sequence information, however, such as ribosomal RNA operons, every micro-organism— even those dead or uncultivated—can be identified by something it has in common with others, with the result that only one genotypical method is needed. Currently available sequence databases and analysis tools, such as the National Center for Biotechnology Information or Ribosomal Database Project are not very useful for rapid identification of clinically relevant micro-organisms. Amongst the drawbacks are low user-friendliness of analytical tools and poor quality of the data included in the databases. We developed therefore, a new intuitive user-interface hypertext based on available software (FASTA, CLUSTALW). For all new database entries, such as annotated sequences from culture-collection strains, a hypervariable ribosomal DNA region, no longer than one sequence run, was selected. This region is flanked by two strongly conserved nucleotide stretches which serve as an invariable annealing target for PCR and DNA-sequencing primers. The diagnostic procedure starts with a ribosomal DNA sequence from the specimen to be identified which is submitted to the query interface. From an interpreted similarity search, a species or genus name for the specimen in question is returned. If the first results are ambiguous or do not define to species level, hints for further molecular (internal transcribed spacer) and conventional differentiation are offered (“sequential and polyphasic” approach). An integrated phylogeny browser allows for the immediate control of the phylogenetic placement of the identified species. Further genus, species descriptions, and taxonomic information is created out of the database according to the search result on World Wide Web (WWW) pages. For quality control, sequence electropherograms of newly determined sequences are deposited on the WWW server. Because of the open hypertext-structure of the Ribosomal Differentiation of Medical Microorganisms (RIDOM) system, many context-sensitive links to other available WWW services are stablished thereby augmenting the information content (table). A report generator searches the internet and the RIDOM server for information regarding the determined species, and presents a one-page summary of

The paper discusses the Infrared Space Observatory (ISO) optical subsystem, a cryogenically cooled telescope featuring main baffle and sunshade. The telescope, a 60-cm Ritchey-Chretien type, focuses the beam to the four scientific instruments located in its focal plane. The extremely low temperature, 1.8 K, is provided by the payload module cryostat, filled with superfluid He. The design of these elements is supported by different mathematical models and by dedicated elementary tests linked to operation in the cryogenic environment. Tests performed at ambient and cryogenic temperatures demonstrate the good behavior of the optical subsystems for thermal, mechanical, and optical performance.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.