State of the art of contaminated site management in The Netherlands: policy framework and risk assessment tools.

This paper presents the policy framework of contaminated site management in The Netherlands and the corresponding risk assessment tools, including innovations that have taken place since an overview was published in 1999. According to the Dutch Soil Protection Act assessment framework, soils are subdivided into three quality classes: clean, slightly contaminated and seriously contaminated. Historic cases of slightly contaminated soils are managed in a sustainable way by re-use of soil material within a region on the basis of risk-based and land use specific Maximal Values and Background Values. In case of serious soil contamination remediation is in principle necessary and the urgency of remediation has to be determined based on site-specific risks for human health, the ecosystem and groundwater. The major risk assessment tools in The Netherlands are the CSOIL exposure model (human health risks and food safety), Species Sensitivity Distributions and the Soil Quality Triad (ecological risks), along with a procedure to assess the risks due to contaminant spreading to and in the groundwater. Following the principle 'simple if possible, complex when necessary', tiered approaches are used. Contaminated site practices are supported with web-based decision support systems.

Coexistence of tight and loose bundled states in a model of bacterial flagellar dynamics.

Many microorganisms propel themselves through their fluid environment by means of multiple rotating flagella that self-organize to form bundles, a process that is complex and poorly understood. In the present work, the bundling behavior of a pair of flexible flagella, each driven by a constant torque motor, is investigated, using a mathematical model incorporating the fluid motion generated by each flagellum as well as the finite flexibility of the flagella. The initial stage of bundling is driven purely by hydrodynamics but the final state of the bundle is determined by a nontrivial balance between hydrodynamics and elasticity. As the flexibility of the flagella increases a regime is found where, depending on initial conditions, one finds bundles that are either tight, with the flagella in mechanical contact, or loose, with the flagella intertwined but not touching. That is, multiple coexisting states of bundling are found. The parameter regime (in terms of flexibility and distance between motors) at which this multiplicity occurs is comparable to the parameters for a number of bacteria.

Genome sequence of the edible cyanobacterium Arthrospira sp. PCC 8005.

We determined the genome sequence of Arthrospira sp. PCC 8005, a cyanobacterial strain of great interest to the European Space Agency for its nutritive value and oxygenic properties in the Micro-Ecological Life Support System Alternative (MELiSSA) biological life support system for long-term manned missions into space.

The surgical treatment of stage III empyema: the effect on lung function.

AIM: The aim of this study was to evaluate the surgical treatment of stage III empyema. METHODS: Between 2002 and 2005, 30 patients underwent surgery for treatment of diagnosed stage III empyema preoperatively. Patients were referred for spirometry to evaluate lung function postoperatively. RESULTS: Twenty nine patients underwent primary thoracotomy because of an extended stage III empyema, 1 patient video-assisted thoracoscopic surgery (VATS). Mean age was 62 years. Mean period from onset of symptoms until hospital admission was 29 days and mean time interval between admission and surgery was 11 days. Intraoperative complication happened in one patient (3%), in whom a phrenic nerve lesion was diagnosed. Overall mortality rate was 3%. In 17 patients postoperative spirometry was performed, showing normal vital capacity in 59% of the patients. CONCLUSION: There was no reluctance in performing primary thoracotomy in our population with a stage III empyema. Decortication by means of thoracotomy restored the complete expansion of the lung; the authors claim that vital capacity returned to normal values, as it was shown by the spirometry results postoperatively. Early referral to the respiratory department in case of a non-responding pneumonia and early surgical consultation in case of a parapneumonic effusion, will prevent progression to an extensive organized stage III empyema requiring decortication by thoracotomy.

Stabilised 111In-labelled DTPA- and DOTA-conjugated neurotensin analogues for imaging and therapy of exocrine pancreatic cancer.

Neurotensin (NT) receptors are overexpressed in exocrine pancreatic cancer and Ewing's sarcoma. The potential utility of native NT in cancer diagnosis and therapy is, however, limited by its rapid degradation in vivo. Therefore, NT analogues were synthesised with modified lysine and arginine derivatives to enhance stability and coupled either to DTPA, to enable high specific activity labelling with indium-111 for imaging, or to DOTA, to enable high specific activity labelling with beta-emitting radionuclides, such as lutetium-177 and yttrium-90. Based on serum stability (4 h incubation at 37 degrees C in human serum) and receptor binding affinity, the five most promising analogues were selected and further evaluated in in vitro internalisation studies in human colorectal adenocarcinoma HT29 cells, which overexpress NT receptors. All five NT analogues bound with high affinity to NT receptors on human exocrine pancreatic tumour sections. The analogues could be labelled with (111)In to a high specific activity. The (111)In-labelled compounds were found to be very stable in serum. Incubation of HT29 cells with the (111)In-labelled analogues at 37 degrees C showed rapid receptor-mediated uptake and internalisation. The most promising analogue, peptide 2530 [DTPA-(Pip)Gly-Pro-(PipAm)Gly-Arg-Pro-Tyr-tBuGly-Leu-OH] was further tested in vivo in a biodistribution study using HT29 tumour-bearing nude mice. The results of this study showed low percentages of injected dose per gram tissue of this (111)In-labelled 2530 analogue in receptor-negative organs like blood, spleen, pancreas, liver, muscle and femur. Good uptake was found in the receptor-positive HT29 tumour and high uptake was present in the kidneys. Co-injection of excess unlabelled NT significantly reduced tumour uptake, showing that tumour uptake is a receptor-mediated process. With their enhanced stability, maintained high receptor affinity and rapid receptor-mediated internalisation, the (111)In-labelled DTPA- and DOTA-conjugated NT analogues are excellent candidates for imaging and therapy of exocrine pancreatic cancer, peptide 2530 being the most promising analogue.

Strain-specific genes of Helicobacter pylori: distribution, function and dynamics.

Whole-genome clustering of the two available genome sequences of Helicobacter pylori strains 26695 and J99 allows the detection of 110 and 52 strain-specific genes, respectively. This set of strain-specific genes was compared with the sets obtained with other computational approaches of direct genome comparison as well as experimental data from microarray analysis. A considerable number of novel function assignments is possible using database-driven sequence annotation, although the function of the majority of the identified genes remains unknown. Using whole-genome clustering, it is also possible to detect species-specific genes by comparing the two H.pylori strains against the genome sequence of Campylobacter jejuni. It is interesting that the majority of strain-specific genes appear to be species specific. Finally, we introduce a novel approach to gene position analysis by employing measures from directional statistics. We show that although the two strains exhibit differences with respect to strain-specific gene distributions, this is due to the extensive genome rearrangements. If these are taken into account, a common pattern for the genome dynamics of the two Helicobacter strains emerges, suggestive of certain spatial constraints that may act as control mechanisms of gene flux.

Universal Linkage System: versatile nucleic acid labeling technique.

Over the last two decades nonradioactive nucleic acid labeling and detection systems have overcome the safety, disposal, stability and cost problems that are associated with radioactive techniques. Besides traditional, enzyme-mediated, nonradioactive labeling methods (e.g., random priming, nick translation or labeling by PCR), several chemical labeling systems have been developed (e.g., ULS, psoralen, alkylating agents). These methods provide fluorescent (or hapten) labeled probes for fluorescence in situ hybridization (FISH), comparative genomic hybridization (CGH) and microarray-based techniques. In this review the DNA-based molecular diagnostic applications and perspectives of the Universal Linkage System (ULS) technology will be described.

Quantitative immunohistochemistry of androgen receptors in a microsphere model system and in prostate tissue sections.

OBJECTIVE: To evaluate androgen receptor (AR) levels to predict endocrine therapy response and prognosis. STUDY DESIGN: A sepharose microsphere model was employed to establish the relationship between level of immunohistochemical staining density and both antigen and primary antibody (F39.4.1) concentration. Subsequently, the results of the model system were compared with the results in routine prostate sections. RESULTS: A log-linear relationship was observed between optical density (OD) and primary antibody dilution measured in immunostained, antigen-coated microspheres with moderate antigen density. Similar titration curves were observed in prostate sections at the same dilution range, indicating that the microsphere model can be extrapolated to routine tissue sections. With microspheres with high coating density, the loglinear range of dilutions shifted to higher dilutions. CONCLUSION: Differences in AR levels in prostate tissue sections might be more accurately detected by comparison of titration curves of primary antibody than by comparison of OD values at a fixed primary antibody dilution.

Nursing students' responses to ethical dilemmas in nursing practice.

In literature as well as in nursing practice a growing concern about nurses' ethical competence can be observed. Based on the cognitive theory of moral development by Kohlberg, this research examined nursing students' ethical behaviour in five nursing dilemmas. Ethical behaviour refers not only to the ethical reasoning of nursing students but also to the relationship between reasoning and behaviour. Kohlberg's definition of morality was refined by adding a care perspective. The results show that the majority of students can be located in the fourth moral stage according to Kohlberg's theory, that is, the conventional level of moral development. This finding implies that students are still guided by professional rules, norms and duties, and have not (yet) succeeded in making personal ethical decisions on the basis of their own principles and acting according to such decisions.

Elevated estrogen receptor expression in human prostatic stromal cells by androgen ablation therapy.

PURPOSE: The presence of estrogen receptors (ER) in human prostatic tissue is a longstanding, controversial issue. In a few experimental animal models androgen deprivation was shown to be associated with a spontaneous increased ER expression in prostatic tissue. We intended to study whether these observations also apply to human prostatic tissue. MATERIALS AND METHODS: Estrogen receptor expression by stromal and glandular cells was studied by immunohistochemistry in prostatectomy specimens of 21 patient with prostate cancer, treated for 3 months with a luteinizing hormone-releasing hormone (LHRH) agonist and flutamide. In addition 2 patients treated with estrogens were also examined. For comparison, ER expression was also studied in a series of 18 prostatectomy specimens of untreated patients. RESULTS: The specimens of patients treated with androgen blockade showed atrophic changes of the gland as well as basal cell hyperplasia, features characteristic for this therapy. Although stromal cells of prostatectomy specimens from untreated patients were largely ER negative, those of patients exposed to androgen ablation therapy or estrogen therapy had an intense nuclear ER expression in a great number of stromal cells around prostatic glands. Sporadic epithelial cells lining the glands displayed some nuclear ER expression. Prostatic glands from treated patients with basal cell hyperplasia lacked ER expression. In all treated and untreated cases the carcinoma cells were ER negative. CONCLUSIONS: Androgen deprivation leads to an upregulation of stromal ER expression in human prostate. Estrogen-induced morphological epithelial changes could be explained by a paracrine interaction between stromal and epithelial cells.

The relationship between education and ethical behavior of nursing students.

Based on the cognitive theory of moral development of Kohlberg, refined by the addition of the dimension "ethics of care" and the educational theory of Janssen, the relationship of education and ethical behavior of nursing students was examined. Ethical behavior referred not only to the ethical reasoning of students but also to the relationship between this reasoning and their behavior. This study examined the responses of 2,624 nursing students to five ethical nursing dilemmas included in the Ethical Behavior Test by relating them to four educational variables: students' level of education, level of enrollment, school, and students' perceptions of the educational process. A significant relationship between education and ethical behavior was found.

Proliferation of gemistocytic cells and glial fibrillary acidic protein (GFAP)-positive oligodendroglial cells in gliomas: a MIB-1/GFAP double labeling study.

Large gemistocytic cells are well-known elements of glial tumors. Recently, miniature gemistocytic cells and neoplastic glial fibrillary acidic protein (GFAP)-positive oligodendroglial cells, which are regularly seen in oligodendrogliomas, have been termed "transitional cells". The proliferative activity of the gemistocytic cell types and the GFAP-positive (gliofibrillary) oligodendrocytes was determined in eight astrocytomas, seven gemistocytic astrocytomas, eight glioblastomas, two monstrocellular glioblastomas, seven oligodendrogliomas and three mixed oligo-astrocytomas by immunohistochemical staining of the proliferation marker MIB-1 in combination with immunostaining for GFAP. Both large gemistocytic cells and the transitional cells showed cytoplasmic GFAP-positive staining. Neither in the classic gemistocytes nor in the minigemistocytes nuclear immunostaining for the MIB-1 antibody was observed. In contrast, MIB-1 staining was seen in the gliofibrillary oligodendrocytes. It is concluded that both large and miniature gemistocytic cell types contrast with gliofibrillary oligodendrocytes by their inability to proliferate.

Sex steroid receptor expression in 'carcinoid' tumours of the breast.

Nine 'carcinoids' of the breast (argyrophilic carcinomas) were examined for the presence of estrogen receptor (ER), progesterone receptor (PR), and androgen receptor (AR), using immunohistochemistry. The tumours were selected on the basis of their histo-morphological appearance and positive Grimelius stain. All cases were immunoreactive for neuron-specific enolase (NSE). In one case the tumour cells were intensely chromogranin A positive. All cases were ER positive, while 5 cases expressed AR and 5 cases PR. Immunostaining for ER and simultaneous demonstration of argyrophilia or chromogranin A expression in chromogranin A positive argyrophilic carcinoid tumour of the breast provided further evidence that neuroendocrine cells in breast tumours express sex steroid receptors. The similarity in sex steroid receptor expression pattern in 'carcinoids' of the breast and the more common categories of breast cancer suggests an identical responsiveness to endocrine therapy.

Neurofibromatosis type 2 protein co-localizes with elements of the cytoskeleton.

The product of the neurofibromatosis type 2 (NF2) tumor suppressor gene is a 595-amino-acid protein bearing resemblance to a family of band-4.1-related proteins. These proteins, including ezrin, radixin, and moesin, probably function as molecular linking proteins, connecting the cytoskeleton to the cell membrane. On the grounds of the homology to the ezrin, radixin, and moesin proteins and on the basis of its predicted secondary structure, the NF2 protein is also thought to act as a cytoskeleton-cell membrane linking protein. Using monoclonal antibodies to amino- and carboxyl-terminal synthetic NF2 peptides we demonstrate the co-localization of the NF2 protein with elements of the cytoskeleton in a COS cell model system and in cultured human cells. Furthermore, the presence of the NF2 protein in tissue sections is shown. The monoclonal antibodies specifically stain smooth muscle cells and the stratum granulosum of the human epidermis. In cultured smooth muscle cells the NF2 protein co-localizes with actin stress fibers. Immunoelectron microscopy demonstrates the presence of the NF2 protein associated with keratohyalin granules and to a lesser extent with intermediate filaments in the human epidermis. We conclude that the NF2 protein is indeed associated with multiple elements of the cytoskeleton.

Sites required for GltC-dependent regulation of Bacillus subtilis glutamate synthase expression.

The Bacillus subtilis gltAB genes, coding for the two subunits of glutamate synthase, are transcribed divergently from the gltC gene, encoding a LysR-type transcriptional activator of gltAB. The predicted gltA and gltC transcription start sites are separated by 51 to 52 bp. A 15-bp, consensus binding site (Box I) for LysR-type proteins was found centered at position -64 with respect to the gltA transcription start. This site was shown by mutational analysis to be required both for GltC-mediated activation of gltA and for autorepression of gltC. Box II, which is similar to Box I, is centered 22 bp downstream of Box I and overlaps the -35 region of the gltA promoter. Box II was found to be essential for activation of gltA but not for gltC autoregulation. Introduction of approximately one additional helical turn of DNA between Box I and Box II enhanced gltA expression 7- to 40-fold under nonactivating conditions and about 2-fold under activating conditions. Expression of gltA was dramatically decreased when the distance between Box I and Box II was altered by a nonintegral number of helical turns of DNA. gltC autorepression was abolished by most of the inserts between Box I and Box II but was augmented by adding one helical turn.

The product of the NF2 tumour suppressor gene localizes near the plasma membrane and is highly expressed in muscle cells.

Neurofibromatosis type 2 (NF2) is a disease resulting in the formation of schwannomas of the eighth cranial nerve, and other central nervous system tumours. A tumour suppressor gene has been found to be responsible for this disorder. The 595 amino acid NF2 protein shows a great deal of homology to a superfamily of membrane organizing proteins. To generate antibodies against the NF2 protein four synthetic peptides (SP) were injected in rabbits. COS cells transfected with an NF2 cDNA construct in an expression vector were used for immunocytochemical staining experiments; lysates of transfected COS cells were used for Western blotting experiments, as were lysates of E. coli cultures transformed with an NF2 cDNA construct subcloned in a prokaryotic expression vector. In western blots all sera detected a band indicating the appropriate molecular weight in lysates of transfected COS cells and E. coli. Immunocytochemical staining experiments indicate that the NF2 protein localizes in or near the cell membrane. Immunohistochemical staining of human tissue sections demonstrated the presence of the NF2 protein in muscle-, and Schwann cells. These results support the hypothesis that the NF2 protein functions as a membrane organizing element.

Immunohistochemical detection of the androgen receptor with monoclonal antibody F39.4 in routinely processed, paraffin-embedded human tissues after microwave pre-treatment.

We describe the immunohistochemical detection of the human androgen receptor (AR) in routinely processed, paraffin-embedded tissue with the monoclonal antibody (MAb) F39.4. Deparaffinized sections were heated in a microwave oven for antigen retrieval. A panel of human male- and female-derived tissues was investigated. We observed a nuclear staining pattern consistent with previous results on frozen sections. Moreover, we studied the possibility of detecting AR in prolonged formalin-fixed tissue and in paraffin-embedded archival material. After prolonged fixation times or long-term storage of paraffin-embedded tissue, the staining intensity for the AR did not deteriorate. Blocking experiments with the specific synthetic peptides demonstrated the specificity of this technique. We conclude that this method is specific, allows retrospective AR studies, and offers optimally preserved morphology.

Androgen receptor status in localized and locally progressive hormone refractory human prostate cancer.

Heterogeneity in human androgen receptor (hAR) expression in prostate cancer is considered to be implicated in tumor progression. hAR expression was therefore studied immunohistochemically in localized and locally progressive, hormone refractory (HR) prostate cancer. Because altered functional activity of the hAR may be due to changes in the structural integrity of the hAR gene, exons 2 to 8 of the hAR gene were assessed for mutations by single-strand conformation polymorphism (SSCP) analysis and exon 1 was analyzed for the size of the CAG repeat. The hormone binding capacity, a prerequisite for ligand-regulated receptor function, was determined by a ligand binding assay. Coexpression of the hAR and prostate-specific antigen (PSA) was studied by a sequential double immunoenzymatic staining to verify whether PSA expression is a parameter of hAR function. Almost all human prostatic carcinomas revealed heterogeneous hAR expression, regardless of tumor differentiation and progression. Putative predominance of hAR-negative tumor areas in HR prostate cancer was not observed. No hAR gene mutations or major changes in the CAG repeat were found in the 18 HR carcinomas or in the 9 control samples. Moreover, all selected hAR-expressing cancers were able to bind the synthetic androgen methyltrienolone (R1881). Immunoenzymatic double staining revealed even PSA expression in hAR-negative tumor areas. PSA immunohistochemistry in human prostatic carcinomas therefore is of no use in determining hAR functional activity. Thus, most prostatic carcinomas, even when progressed to a state of hormone insensitivity, contain a structurally intact hAR gene, heterogeneously expressed with retained androgen binding capacity.

Do neuroendocrine cells in human prostate cancer express androgen receptor?

The presence of androgen receptors (AR) in neuroendocrine cells was investigated in benign tissue of 10 prostatectomy specimens, in 12 prostatic adenocarcinomas with focal neuroendocrine differentiation and in 1 case of a pure neuroendocrine small cell carcinoma of the prostate. Neuroendocrine cells were defined by their reactivity with an antibody to chromogranin A. Monoclonal antibody F39.4 directed against the amino-terminal domain of the AR molecule was used to detect AR. AR and chromogranin A were simultaneously visualized with a double immunofluorescence technique. The results indicate that chromogranin positive cells in both benign and malignant prostatic tissue lack detectable expression of AR. No effect of endocrine therapy was noted. These results are in agreement with the hypothesis that prostatic neuroendocrine tumour cells represent an androgen insensitive cell population, which incidentally may expand to replace the androgen-sensitive tumour cell population during androgen ablation therapy.

Mechanisms contributing to the differential haemodynamic effects of bombesin and cholecystokinin in conscious, Long Evans rats.

1. Long Evans rats were chronically instrumented with intravascular catheters and pulsed Doppler probes to assess changes in renal, mesenteric and hindquarters blood flows and vascular conductances in response to bombesin (2.5 micrograms kg-1, i.v.) and cholecystokinin (CCK) (0.5 and 5.0 micrograms kg-1, i.v.). 2. Bombesin caused an increase in heart rate and blood pressure, together with a transient renal vasoconstriction and prolonged mesenteric vasodilatation; there was an early hindquarters vasodilatation followed by vasoconstriction. 3. In the presence of phentolamine, bombesin caused a fall in blood pressure due to enhanced hindquarters vasodilatation; these effects were reversed by propranolol and hence were possibly due to circulating adrenaline acting on vasodilator beta 2-adrenoceptors. 4. During concurrent administration of phentolamine, propranolol and atropine, bombesin caused prolonged tachycardia and a rise in blood pressure. The renal vasoconstrictor and mesenteric vasodilator effects of bombesin were not reduced under these conditions and thus probably were direct and/or indirect non-adrenergic, non-cholinergic (NANC) effects. 5. CCK caused dose-dependent increases in blood pressure accompanied by renal, mesenteric and hindquarters vasoconstriction followed, after the higher dose, by vasodilatations. The lower dose of CCK increased heart rate but there was a bradycardia followed by a tachycardia after the higher dose. 6. Experiments with antagonists as described above indicated the pressor effect of CCK was mediated largely through alpha-adrenoceptors, as were the mesenteric and hindquarters vasoconstrictor effects; CCK exerted NANC negative chronotropic effects. 7. All the effects of CCK were markedly inhibited by L364,718. This observation, and the finding that L364,718 had no effect on the responses to bombesin, together with the dissimilarities in the regional haemodynamic effects of exogenous CCK and bombesin, indicate that the cardiovascular actions of the latter were not dependent on the release of endogenous CCK.