Improved quality of care for patients undergoing an abdominoperineal excision for rectal cancer.

INTRODUCTION: New diagnostics, the emergence of total mesorectal excision and neoadjuvant treatments have improved outcome for patients with rectal cancer. Patients with distal rectal cancer undergoing an abdominoperineal excision seem to do worse compared to those treated with sphinctersparing techniques. The aim of this study was to evaluate the quality of care for patients undergoing an abdominoperineal excision for distal rectal cancer during the last 15 years. MATERIALS AND METHODS: All patients with rectal cancer, who underwent an abdominoperineal excision between December 1996 and December 2010 in 5 Dutch hospitals were analysed. Patients were divided into three cohorts; 1996-2001, 2001-2005 and 2006-2010. All data was extracted from medical records. RESULTS: 477 patients were identified. There was no significant difference in sex, age, BMI, prior pelvic surgery and ASA stages between the cohorts. MRI became a standard tool in the work-up, the use increased from 4.5% in the first, to 95.1% in the last cohort (p < 0.0001). Neoadjuvant treatment shifted from predominantly none (64.9% in cohort 1) to short course radiotherapy (66.7% in cohort 2) and chemoradiation therapy (55.7% in cohort 3). There was a trend towards a decreased circumferential resection margin involvement in the cohorts (18.8%, 16.7% and 11.4%; p = 0.142). Accidental bowel perforations have significantly decreased from 28.6%, and 21.7% to 9.2% in cohort 3 (p < 0.0001). CONCLUSION: Significant improvements in work-up, neoadjuvant and surgical treatment have been made for patients with low rectal cancer, undergoing an abdominoperineal excision. These improvements result in improved short term outcome.

Novel naphthoquinones from a Streptomyces sp.

Cdc25A assay-guided fractionation of a fermentation broth derived from a Streptomyces sp. resulted in the isolation of four novel naphthoquinones 1-4. Structures of these compounds were deduced by NMR and mass spectrometry. Two of them, 3 and 4, incorporate a modified cysteine residue which is observed for the first time in this class of natural products. Naphthoquinones 1-4 showed weak activity against cdc25A phosphatase.

[Preoperative diagnosis with stereotactic biopsy is a good predictor of breast cancer in radiologically non-benign breast lesions]. / Preoperatieve diagnostische stereotactische biopsie goede voorspeller van mammacarcinoom bij radiologisch niet-benigne mamma-afwijkingen.

OBJECTIVE: To evaluate histological needle biopsy in breast lesions classified radiologically as 'non-benign'. DESIGN: Prospective, descriptive. SETTING: Hospital Velp, Velp, the Netherlands. METHODS: 232 women with an 'uncertain', 'suspicious' or 'malignant' result of mammography, if necessary supplemented by echography, were subjected to histological biopsy from a breast between 1 January 1994 and 1 January 1997. The earlier biopsies were made with a 16 Gauge (G) needle, those after April 1996 with a 14 G needle, as a rule under stereotactic control. In principle, operation was performed after a positive result. Concerning the women operated after the biopsy, the results of the histological examinations were compared in a 2 x 2 table. RESULTS: 165 of the 232 patients (71%) had breast cancer. Of the 59 patients classified roentgenologically as 'uncertain', 15 (25%) had breast cancer, of the 'suspicious' cases this ratio was 44/67 (66%) and of the 'malignant' results it was 106/106 (100%). Operation was performed in 186 women. The biopsy findings and the surgical preparation were in agreement in 169 patients (91%). The sensitivity of the stereotactic biopsy was 90%, its specificity 93%. One woman was over-treated (axillary lymph node resection) because of a biopsy classified as malignant performed on a rare tumour ultimately diagnosed as 'adenomyo-epithelioma with epithelial atypia'. The proportion of false-negative results was 36%. The predictive value of a positive result was 99%, that of a negative result 63%. CONCLUSION: A diagnostic stereotactic biopsy after roentgenological classification based on mammography and echography had a good predictive value regarding the probability of breast cancer.

A new UHV angle encoder for high-resolution synchrotron radiation monochromators.

The high precision of 0.1 arcsec required for the positioning of optical elements in new two-axes monochromators at the undulator beamlines at BESSY II has led to the development of UHV-compatible high-precision angle encoders. Mounted directly on the rotation axes, they provide substantial advantages over measuring systems connected outside the vacuum vessel. Making use of a fast closed-loop control system, an accuracy of 0.1 arcsec at a resolution of less than 0.01 arcsec has been experimentally verified.

Chicken oviductal ecto-ATP-diphosphohydrolase. Purification and characterization.

An ecto-ATP diphosphohydrolase (ATPDase) was purified to homogeneity from vesiculosomes shed from chicken oviduct. First, the ecto-ATPDase-enriched vesiculosomes were concentrated by filtration, differential centrifugation, and exclusion chromatography. Next, the nonionic detergent, Nonidet P-40, was used to extract the ecto-ATPDase from vesiculosomal membranes, and the solubilized enzyme was further purified by ion exchange (DEAE-Bio-Gel) and lentil-lectin-Sepharose 4B chromatography. In the final stage, immunoaffinity chromatography was utilized to obtain purified ecto-ATPDase. More than 25,000-fold purification was achieved. Specific activity of the purified enzyme was greater than 800 micronol/min/mg of protein with MgATP as the substrate, the highest ever reported for an ATPDase. The enzyme also hydrolyzed other nucleoside triphosphates in the presence of magnesium at similar rates and CaATP and MgADP at lower rates. The molecular mass of the purified glycoprotein was 80 kDa as determined by SDS-polyacrylamide gel electrophoresis and Western blot analysis. Based on its enzymatic properties, the relationship of the chicken oviduct ecto-ATPDase with other reported ATPDases and ecto-ATPases is discussed.

Aneurysm formation in modified human umbilical vein grafts.

OBJECTIVES: Aneurysm formation in Human Umbilical Vein Grafts has been reported to be as high as 65% after 5 years. One of the causes might be the structure of the Biograft-wall and in 1985 a new method of processing the graft was begun. In Groningen this new improved Biograft has been used since late 1986. DESIGN: Duplex scanning was used to examine the frequency of aneurysm formation in the new improved Biograft. MATERIALS: Sixty-nine patent Biografts have been examined in a period up to 6 years after implantation. MAIN RESULTS: Aneurysms were found in only 17% of grafts although the frequency increased with time. Dilatation was common but may be due to a more elastic graft. CONCLUSION: These findings justify the continued use of the new Biograft as a substitute for arterial femoropopliteal reconstructions.

Genotoxicity of 17 gyrase- and four mammalian topoisomerase II-poisons in prokaryotic and eukaryotic test systems.

The genotoxic potency of certain classes of topoisomerase II poisons is correlated with their affinity to the topoisomerase protein rather than with the presence of 'classical' structural alerts for DNA reactivity: bacterial topoisomerase II poisons (specifically named gyrase inhibitors) are highly genotoxic in prokaryotic systems; mammalian topoisomerase II poisons are potent mutagens/clastogens in eukaryotic systems. Studies with bacterial, lower eukaryotic and mammalian genotoxicity tests were performed to draw structure-activity conclusions and address risk-benefit considerations for the class of quinolone gyrase inhibitors. All 17 gyrase inhibitors investigated in this study showed genotoxic activity in Salmonella typhimurium strain TA102 and the SOS test. The genotoxic and the toxic activities increased in a highly parallel fashion from the parent compounds, nalidixic acid and oxolinic acid, to the new generation fluoroquinolones. Generally, the most potent fluoroquinolones also show clear-cut positive effects in eukaryotic test systems, although at concentrations 100-1000-fold higher than those effective in bacteria and also 100-1000-fold higher than the minimal genotoxic concentrations of antitumour topoisomerase II inhibitors (ellipticine, teniposide, mAMSA) used as reference compounds. However, subtle structural modifications of the quinolones can strongly diminish the preferential genotoxicity in the prokaryotic test systems.

Identification and immunolocalization of ecto-ATPDase in chicken stomach.

The distribution of the extracellular adenosine tri- and di-phosphatase (ecto-ATPDase) in adult chicken tissues was investigated using a monoclonal antibody (MC18) generated previously from chicken oviduct. Ecto-ATPDase was determined to be most abundant in stomach by Western blot analysis of crude tissue homogenates. The ecto-ATPDase activity from solubilized stomach microsomes and a purified oviduct control was depleted 64% and 72%, respectively, by immunoprecipitation with MC18. Both oviduct and stomach ecto-ATPDases had an M(r) of approximately 80 kDa based on SDS-PAGE analysis. In addition, the enzymology of the ecto-ATPDase from both tissues was very similar. It is concluded that the same ecto-ATPDase is present in stomach and oviduct. Furthermore, immunolocalization of the stomach ecto-ATPDase with MC18 showed the enzyme to be localized in the apical membranes of the oxyntico-peptic cells, suggesting a role for the ecto-ATPDase in secretion.

Properties of and proteins associated with the extracellular ATPase of chicken gizzard smooth muscle. A monoclonal antibody study.

The chicken gizzard smooth muscle extracellular ATPase (ecto-ATPase) is a low abundance, high specific activity, divalent cation-dependent, nonspecific nucleotide triphosphatase (NTPase). The ATPase is a 66-kDa glycoprotein with a protein core of 53 kDa (Stout, J.G. and Kirley, T.L. (1994) J. Biochem. Biophys. Methods 29, 61-75). In this study we evaluated the characteristics of a bank of monoclonal antibodies raised against a partially purified chicken gizzard ecto-ATPase. 18 monoclonal antibodies identified by an ATPase capture assay were tested for effects on ATPase activity as well as for their Western blot and immunoprecipitation potential. The five most promising monoclonal antibodies were used to immunopurify the ecto-ATPase. The one-step immunoaffinity purification of solubilized chicken gizzard membranes with all five of these monoclonal antibodies isolated a 66-kDa protein whose identity was confirmed by N-terminal sequence analysis to be the ecto-ATPase. Several of these monoclonal antibodies stimulated ecto-ATPase activity similar to that observed previously with lectins. Western blot analysis revealed that three of the five monoclonal antibodies recognized a major immunoreactive band at 66 kDa (53-kDa core protein), consistent with previous purification results. The other two antibodies recognized proteins of approximately 90 and 160 kDa on Western blots. The 90-kDa co-immunopurifying (and presumably associated or related) protein was identified by N-terminal analysis as LEP100, a glycoprotein that shuttles between the plasma and lysosomal membranes. The approximately 160-kDa co-immunopurifying protein was identified by N-terminal analysis as integrin, a protein involved in extracellular contacts with adhesion molecules. Extended N-terminal sequence analysis of the immunopurified 66-kDa ecto-ATPase revealed some sequence homology with mouse lysosomal associated membrane protein. Tissue distribution of the ecto-ATPase showed that the highest levels of protein were expressed in muscle tissues (cardiac, skeletal, and smooth) and brain.

Ion channel enzyme in an oscillating electric field.

To explain the electrical activation of several membrane ATPases, an electroconformational coupling (ECC) model has previously been proposed. The model explained many features of experimental data but failed to reproduce a window of the field intensity for the stimulated activity. It is shown here that if the affinities of the ion for the two conformational states of the transporter (one with binding site on the left side and the other on the right side of the membrane) are dependent on the electric field, the field-dependent transport can exhibit the observed window. The transporter may be described as a channel enzyme which opens to one side of the membrane at a time. It retains the energy-transducing ability of the earlier ECC models. Analysis of the channel enzyme in terms of the Michaelis-Menten kinetics has been done. The model reproduced the amplitude window for the electric field-induced cation pumping by (Na,K)-ATPase.

Production of monoclonal antibodies to staphylococcal enterotoxin A.

Spleen cells from mice immunized with staphylococcal enterotoxin A were successfully fused with NS-1 mouse myeloma cells. Two of the four clones studied produced monoclonal antibodies to staphylococcal enterotoxin A in growth medium which showed titers of greater than 10(6) to 10(7) when tested by the indirect enzyme-linked immunosorbent assay. These monoclonal antibodies showed reactivity with enterotoxins A and E in the enzyme-linked immunosorbent assay. However, the reactivity was higher with enterotoxin A than with enterotoxin E. Nanogram quantities of crude staphylococcus enterotoxin A from Staphylococcus aureus growth were detected by the monoclonal antibodies in electroimmunoblots via autoradiography.

Criteria for the standardization of Salmonella mutagenicity tests: results of a collaborative study. II. Studies to investigate the effect of bacterial liquid culture preparation conditions on Salmonella mutagenicity test results.

The influence of various parameters and growth conditions in the "overnight culture" of Salmonella typhimurium strains on mutagenicity test results was investigated. A number of factors were first suspected to be of some importance for the quantitative outcome of the mutagenicity test. None of them, however, was found to influence the results to such a marked extent as to be a major source of variability. Only the brand of nutrient broth used for the propagation of the bacteria proved finally to have a certain effect on the number of (spontaneous and induced) revertant colonies, although no precise and quantitative statements can be made with regard to a possible standardization of this experimental segment in the Salmonella mutagenicity test. The occurrence of such unpredictable but noticeable influences is, however, evidence for the importance of an intralaboratory optimization and standardization of all parts of the test procedure.

Reproducibility of and experiences with the BHK cell transformation assay.

Transformation of BHK 21 C 13 cells was investigated using the ability of transformed cells to reproduce in semi solid agar (anchorage independent growth). A number of modifications to previously published methods have been made, our assays were carried out on 16 compounds, including both carcinogens and non-carcinogens as judged by in vivo bioassay. Reproducibility of test results within the laboratory and with data derived from literature could be shown. Experiences concerning the optimal growth of transformed cells and the threshold level to differentiate between positive and negative results are discussed.

Transformation of BHK 21/CL 13 cells by various polycyclic aromatic hydrocarbons using the method of Styles.

Nine polycyclic aromatic hydrocarbons (PAHs) were investigated by the cell-transformation assay method of Styles. Benzo(a)pyrene [B(a)P], chrysene (CH), 3-methylcholanthrene (3-MC), benz(a)anthracene (BA), benzo(b)fluoranthene [B(b)F], and dibenz(a,h)anthracene (DBA) were tested, including liver homogenate, and showed dose-effect relationships and a more than 2-fold increase of transformation rates at LC50. Due to variations of the test method our results differed quantitatively from the data published by Purchase and Styles. Discrimination between the known carcinogens listed above and the noncarcinogens, phenanthrene (PA) and anthracene (AC), lacking a dose-effect relationship was, however, possible. Benzo(e)pyrene [B(e)P] was regarded as positive although producing only a 2-fold increase in the number of transformed colonies.

Mutagenic and cell transforming activities of 1-chlor-2,4-dinitrobenzene (DNCB) and squaric-acid-dibutylester (SADBE).

In the Salmonella/microsome test, DNCB was mutagenic for TA100, TA1538, and TA98, whereas SADBE did not induce mutations in the test system. The ability of the compounds to transform BHK cells being able to reproduce in semi-solid agar was investigated. DNCB induced a dose-dependent increase in transformed cells, SADBE did not show this effect.

Cell transformation of BHK 21 C 13 cells by various chemicals with and without S-9 mix.

Transformation of BHK 21 C 13 cells was evaluated by the ability of transformed cells to reproduce in semi solid agar (anchorage independent growth). The in vitro test system was carried out according to Styles with modifications. All compounds were tested with and without metabolic activation (S-9 mix). The results demonstrate the importance of a metabolizing system in this cell transformation assay.

Studies on the detection of chemical carcinogens using a mammalian cell transformation assay. A correlated study of BHK cell transformation and bacterial mutagenicity.

Transformation of BHK 21/Cl 13 cells was used as a test system to detect the carcinogenic potential of Busulfan (Myleran). To correlate carcinogenicity of the compound with its mutagenic activity, bacterial mutagenicity was demonstrated in the Salmonella/microsome test.

Testing propafenone hydrochloride in the Ames Salmonella microsome system and in mammalian cytogenetic systems (bone marrow, spermatogonia).

2'-(2-Hydroxy-3-propylaminopropoxy)-3-phenyl-propiophenone-hydrochloride (propafenone-HCl, Rytmonorm) was tested for mutagenic activity in the Salmonella microsome system (Ames test) and in mammalian cell systems. Neither in the Ames test (62.5-1000 microgram/plate) nor in the bone marrow cells and spermatogonia of Chinese hamster (injected doses: 1.57, 3.13, 6.27 mg/kg) there is any evidence for an enhancement of mutation frequencies or chromosome aberration rates. Also, the micronucleus rates were in the control range. Under the experimental conditions of this investigations propafenone-HCl was not mutagenic.