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Chrysanthemate insecticides like ( S )-bioallethrin, natural pyrethins, and related pyrethroids are subjected to extensive hydrolytic and oxidative degeneration by the mammalian metabolism, leading to a complex series of metabolites partially conjugated and finally eliminated in the urine. The major oxidation products of chrysanthemic acid, cis -(E)- and trans -(E)-chrysanthemumdicarboxcylic acid ( cis -(E) and trans -(E)-CDCA), were synthesized and their structures were established by nuclear magnetic resonance spectrometry (H 1 -NMR) and mass spectrometry (MS). Diastereoselective separation was by high performance liquid chromatography (HPLC) and capillary gas chromatography (GC). An analytical method for extraction and identification of CDCA from human urine was developed. Quantitation was by gas chromatography and electron-impact mass spectrometry (GC/MS). The limit of detection was 20 μg/l for cis -(E)-CDCA and 10 μg/l for trans -(E)-CDCA. To test the applicability of the presented method, urine samples of humans exposed to ( S )-bioallethrin were investigated. Urinary peak excretion of trans -(E)-CDCA occurred within 24 h after exposure.

The integration inverse method has been extensively investigated in the past decade; however, none of the researches fully addresses the stability analysis of the method that is crucial to successful implementation. This paper presents a stability test to analyse the global stability of the integration inverse method for linear time-invariant systems. A stable solution may be obtained from careful selection of the discretisation interval using the proposed stability test. A discrete model is derived to approximate the Newton's scheme in the inverse method. With this approximate model, the stability of the inverse method can be examined. The stability test is exact for linear systems and can be extended to the inverse method for non-linear aircraft simulations by considering an equivalent linear model for each point of the flight envelopes. Guidelines for selection of appropriate reference points in the inverse simulation are given.

Pyrethroids are neurotoxic by prolonging the opening of the sodium channel (Aldridge 1990). In humans, a variety of reversible symptoms have been reported (He et al. 1988, 1989), including abnormal facial sensations like burning, itching, or tingling sensation, paresthesia, and irritations of the skin, mucosa, and respiratory tract. Non-specific symptoms for pyrethroid exposure include headache, dizziness, nausea, and epigastric pain.

Applications of high-resolution gas chromatography and high-resolution mass spectrometry (GC-MS) for identification and quantitation of trace amounts of pyrethroid metabolites in human urine samples are demonstrated. The method covers the pyrethroid metabolitescis- andtrans-3-(2,2-dichlorovinyl)-2,2-dimethyl-cyclopropane carboxylic acid (cis- andtrans-DCCA),cis-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropane carboxylic acid (cis-DBCA), 4-fluoro-3-phenoxybenzoic acid (FPBA), and 3-phenoxybenzoic acid (3-PBA). After acid-induced hydrolysis of urine samples and exhaustive solvent extraction, a carbodiimide-coupled esterification of the free carboxylic acids with hexafluoroisopropanol (HFIP) is applied. Identification of the derivatives formed is achieved by low-resolution electron-impact mass spectrometry (EIMS) using an ion-trap detector. Quantitation was by capillary gas chromatography—high-resolution mass spectrometry using negative chemical ionization (GC-NCIMS). 2-Phenoxybenzoic acid (2-PBA) served as internal standard. The limits of detection forcis- andtrans-DCCA,cis-DBCA, FPBA and 3-PBA were 0.03 μg L−1 or below. The applicability of the presented method was tested on urine samples of persons exposed to low levels of pyrethroids.

Published in the series Biomonitoring Methods, Vol. 13 (2013) The article contains sections titled: General principles Equipment, chemicals and solutions Equipment Chemicals Solutions Internal standard Calibration standards Specimen collection and sample preparation Specimen collection Sample preparation Operational parameters Operational parameters for gas chromatography Operational parameters for alternative gas chromatography Operational parameters for mass spectromety Operational conditions for the alternative GC-MS method Analytical determinations Calibration Calculation of the analytical result Standardisation and quality control Evaluation of the method Precision Accuracy Absolute recovery Detection limits and quantitation limits Sources of error Discussion of the method Appendix Keywords: allethrin; cyfluthrin; cypermethrin; deltamethrin; permethrin; phenothrin; determination in urine; capillary gas chromatography; mass selective detection; analysis in biological materials; occupational monitoring; analytical method; biomarker; metabolites

An analytical method for the simultaneous determination of the pyrethroid metabolites cis and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid, cis 3-(2,2-dibromovinyl)-2,2-dimethylcyclopropane carboxylic acid, 3-phenoxybenzoic acid and 4-fluoro-3-phenoxybenzoic acid in human urine samples is described. The urine is subjected to acid-induced hydrolysis followed by exhaustive solvent extraction, covering both conjugated and free acids, followed by a common derivatisation step yielding the corresponding methyl esters. Quantitation was by diastereomeric, capillary gas chromatography-mass spectrometry. It appears that 4-fluoro-3-phenoxybenzoic acid is a characteristic urinary marker for cyfluthrin exposure. The limits of determination are 0.5–1.0 μg L−1 urine depending on the metabolites concerned. The applicability of the method was tested on urine samples from pest control operators exposed occupationally to cypermethrin and cyfluthrin.

OBJECTIVES: To clarify the three dimensional ultrastructure of proteoglycans, and their relationship with other matrix components in articular cartilage. METHODS: Specimens from rat femoral heads were examined using three techniques: (1) Histochemical staining with cationic polyethyleneimine (PEI), using a pre-embedding or a postembedding method. Some tissues were pretreated with chondroitinase ABC or hyaluronidase. (2) Quick freezing and deep etching (QF-DE). Some specimens were fixed with paraformaldehyde and washed in buffer solution before quick freezing; others were frozen directly. (3) Ultrathin sections were studied after conventional preparation. RESULTS: Proteoglycans were observed as aggregated clumps with PEI staining by the pre-embedding method, but as fine filaments by the postembedding method. They were lost with enzyme digestion; this was also demonstrated by the QF-DE method. The ultrastructure was well preserved by the QF-DE method when fixation and washing procedures were included, but not without these procedures. A fine mesh-like structure was connected to the cell membrane in the pericellular matrix. Filamentous structures suggestive of aggrecans were observed among collagen fibrils. They had side chains, approximately 50 nm in length, which branched from the central filaments at intervals of 10-20 nm, and were occasionally linked to other structures. Many thin filaments were also attached to the collagen fibrils. CONCLUSIONS: The QF-DE method incorporating paraformaldehyde fixation and buffer washing procedures revealed three dimensional, extended structures suggestive of proteoglycans.

As feeding and mating are mutually-exclusive goal-orientated behaviours, we investigated whether brief food deprivation would impair the display of sexual behaviour of male rats. Analysis of performance in a sexual incentive motivation test revealed that, similar to fed males, food-deprived males preferred spending time in the vicinity of receptive females rather than nonreceptive females. Despite this, food-deprived males were more likely to be slow to mate than normally-fed males, and a low dose of the satiety peptide α-melanocyte-stimulating-hormone attenuated the effect of hunger. Using Fos immunocytochemistry, we compared neuronal activity in the vomeronasal projection pathway in response to oestrous cues from receptive females between food-deprived and fed males. As in fed males, more Fos expression was seen in the rostral part of the bed nucleus of the stria terminalis and in the medial preoptic area in food-deprived males, confirming that food-deprived males can recognise and respond to female oestrous cues. However, although there was also an increase in Fos expression in the bed nucleus of the accessory tract and in the posteromedial amygdala in fed males, no increases were seen in these areas in food-deprived rats. We also found selective attenuation in the activation of lateral posterior paraventricular nucleus (lpPVN) oxytocin neurones in food-deprived males. Taken together, the data show that, although food-deprived males can still become sexually motivated, copulation is delayed, and this is accompanied by variations in neuronal activity in the vomeronasal projection pathway. We propose that, in hungry rats, the lpPVN oxytocin neurones (which project to the spinal cord and are involved in maintaining penile erection) facilitate the transition from motivation to intromission, and their lack of activation impairs intromission, and thus delays mating.

Published in the series Analyses of Hazardous Substances in Biological Materials, Vol. 8 (2003) The article contains sections titled: General principles Equipment, chemicals and solutions Equipment Chemicals Solutions and conditioning Calibration standards Specimen collection and sample preparation Sample preparation Operational parameters Operational parameters for high performance liquid chromatography Analytical determination Calibration Calculation of the analytical result Standardisation and quality control Evaluation of the method Precision Accuracy Detection limits Sources of error Discussion of the method Keywords: determination in urine; high performance liquid chromatography; electrochemical detection; HPLC-ED; analysis in biological materials; occupational monitoring; analytical method; biomarker; metabolites

Published in the series Biomonitoring Methods, Vol. 12 (2010) The article contains sections titled: Introduction Overview of the relevant effect parameters, selected according to the screening principles of the Berufsgenossenschaft [Employers' Liability Insurance Association] and according to recently acquired scientific knowledge Appendix: Analytical methods Acetylcholinesterase (AChE) - no screening principle (G-Satz) δ-Aminolevulinic acid in urine - G2 Lead δ-Aminolevulinic acid-dehydratase (ALAD) - G2 Lead Ascorbic acid level - G15 Chromium Calcium and magnesium - G34 Fluorine Cellular antigen stimulation test (CAST)G23 Obstructive respiratory disorders G27 Isocyanates Free erythrocyte porphyrins (FEP) - G2 Lead β-Glucuronidase - G8 Benzene G33 Aromatic nitro or amino compounds G40 Carcinogenic substances, e.g. phenols Glucose-6-phosphate dehydrogenase (G-6-PDH) - G33 Aromatic nitro or amino compounds Haematology (cytology, differential blood count) – G8 Benzene Urine cytology – G33 Aromatic nitro or amino compounds Histamine release test – G24 Skin disorders 8-Hydroxy-2'-deoxyguanosine (8-OHdG) ― G15 Chromium Immunoglobulins (IgE and IgG) ― G23 Obstructive respiratory tract disorders G27 Isocyanates Carbon monoxide-haemoglobin (CO-Hb) – G7 Carbon monoxide Creatinine ― G9 Mercury G32 Cadmium G40 Carcinogenic substances, e.g. phenols Liver enzymes (GGT, AST, ALT, LDH, GLDH) – G40 Carcinogenic substances, e.g. DMF Lymphocyte transformation test – G8 Benzene G40 Carcinogenic substances, e.g. beryllium Methaemoglobin (MetHb) – G33 Aromatic nitro or amino compounds α1-Microglobulin (α1-MG) – G9 Mercury G32 Cadmium β2-Microglobulin (β2-MG) – G9 Mercury G32 Cadmium N-Acetyl-β-D-glucosaminidase (β-NAG) – G9 Mercury G32 Cadmium N-Acetyltransferase (NAT) ― G33 Aromatic nitro or amino compounds Neurotoxic esterase (NTE) ― no screening principle (G-Satz) Nuclear matrix protein 22 (NMP22) ― G33 Aromatic nitro or amino compounds Uridine diphosphate glucuronosyl transferase (UGT) ― G8 Benzene G40 Carcinogenic substances, e.g. phenols Keywords: clinical parameters; immunological parameters; biological monitoring; occupational monitoring; environmental monitoring; biomonitoring; biomarker

Published in the series Analyses of Hazardous Substances in Biological Materials, Vol. 8 (2003) The article contains sections titled: General principles Equipment, chemicals and solutions Equipment Chemicals Solutions Calibration standards Specimen collection and sample preparation Sample preparation Operational parameters Operational parameters for gas chromatography and mass spectrometry Analytical determination Calibration Calculation of the analytical result Standardisation and quality control Reliability of the method Precision Accuracy Detection limits Sources of error Discussion of the method Keywords: determination in blood; determination of the globin adduct; capillary gas chromatography; mass spectrometric detection; analysis in biological materials; occupational monitoring; analytical method; biomarker; metabolites

Published in the series Biomonitoring Methods, Vol. 11 (2007) The article contains sections titled: General principles Equipment, chemicals and solutions Equipment Chemicals Solutions Calibration standards Conditioning the RP 18 columns Specimen collection and sample preparation Sample preparation Operational parameters Operational parameters for gas chromatography Operational parameters for mass spectrometry Analytical determination Calibration Calculation of the analytical result Standardisation and quality control Evaluation of the method Precision Accuracy Detection limits Sources of error Discussion of the method Keywords: determination in urine; capillary gas chromatography; mass spectrometric detection; analysis in biological materials; occupational monitoring; analytical method; biomarker; metabolites

Published in the series Biomonitoring Methods, Vol. 12 (2010) The article contains sections titled: General principles Equipment, chemicals and solutions Equipment Chemicals Solutions Calibration standards Specimen collection and sample preparation Specimen collection Sample preparation Operational parameters Operational parameters for gas chromatography Operational parameters for mass spectrometry Analytical determination Calibration Calculation of the analytical result Standardisation and quality control Evaluation of the method Precision Accuracy Detection limit and quantification limit Sources of error Discussion of the method Keywords: determination in urine; capillary gas chromatography; mass spectrometric detection; analysis in biological materials; occupational monitoring; analytical method; biomarker; metabolites

Published in the series Analyses of Hazardous Substances in Biological Materials, Vol. 9 (2004) The article contains sections titled: Gene-environmental interactions as the basis of individual susceptibility to xenobiotics Interdisciplinary aspects of molecular epidemiology Occupational and environmental medical aspects Applications in occupational and environmental medicine Recommendation for practical applications Keywords: susceptibility; xenobiotics; gene-environment interactions; analysis in biological materials; occupational monitoring; analytical method; biomarker; metabolites

Published in the series Biomonitoring Methods, Vol. 10 (2006) The article contains sections titled: General principles Equipment, chemicals and solutions Equipment Chemicals Solutions Calibration standards Specimen collection and sample preparation Sample preparation Operational parameters Operational parameters for mass spectrometry Analytical determination Calibration Calculation of the analytical result Standardisation and quality control Evaluation of the method Precision Accuracy Detection limits Sources of error Discussion of the method Keywords: determination in plasma; determination in urine; high performance liquid chromatography; tandem mass spectrometric detection; LC/MS/MS; analysis in biological materials; occupational monitoring; analytical method; biomarker; metabolites

Published in the series Analyses of Hazardous Substances in Biological Materials, Vol. 6 (1999) The article contains sections titled: General principles Equipment, chemicals and solutions Equipment Chemicals Solutions Calibration standards Preparation of the C18-column Specimen collection and sample preparation Operational parameters for gas chromatography and mass spectrometry Analytical determination Calibration Calculation of the analytical result Standardization and quality control Reliability of the method Precision Accuracy Detection limit Sources of error Discussion of the method Addendum: Alternative method of sample preparation Keywords: determination in urine; capillary gas chromatography; mass selective detection; analysis in biological materials; occupational monitoring; analytical method; biomarker; metabolites

Published in the series Biomonitoring Methods, Vol. 11 (2007) The article contains sections titled: General principles Equipment, chemicals and solutions Equipment Chemicals Solutions Calibration standards Specimen collection and sample preparation Sample preparation Operational parameters Analytical determination Protein assay NTE activity determination Calibration Calculation of the analytical result Evaluation of the method Precision Accuracy Detection limit Sources of error Discussion of the method Keywords: determination in leukocytes; photometry; analysis in biological materials; occupational monitoring; analytical method; biomarker; metabolites

Published in the series Biomonitoring Methods, Vol. 11 (2007) The article contains sections titled: General principles Equipment, chemicals and solutions Equipment Chemicals Solutions Calibration standards Specimen collection and sample preparation Specimen collection and storage Preparation of the SPE cartridges Sample preparation Operational parameters Operational parameters for gas chromatography Operational parameters for mass spectrometry Analytical determination Calibration Calculation of the analytical result Standardisation and quality control Evaluation of the method Precision Accuracy Detection limit Sources of error Discussion of the method Keywords: determination in blood; capillary gas chromatography; mass spectrometric detection; analysis in biological materials; occupational monitoring; analytical method; biomarker; metabolites

Published in the series Biomonitoring Methods, Vol. 10 (2006) The article contains sections titled: General principles Equipment, chemicals and solutions Equipment Chemicals Solutions Calibration standards Specimen collection and sample preparation Sample preparation Operational parameters Operational parameters for high performance liquid chromatography Analytical determination Calibration Calculation of the analytical result Standardisation and quality control Evaluation of the method Precision Accuracy Detection limits Sources of error Discussion of the method Keywords: determination in urine; high performance liquid chromatography; UV detector; analysis in biological materials; occupational monitoring; analytical method; biomarker; metabolites

Bladder cancer responds favourably to treatment and has a good survival rate, provided it is diagnosed at an early stage. Established methods exist for the early detection, however, their specificity and positive predictive value are not yet satisfactory. Innovative markers have been proposed, but still require validation in prospective studies. We provide a literature-based short overview on the currently available and some proposed markers for the early detection of bladder cancer and evaluate the need for validation in further studies. We further provide some first results of such a recently finished study in an occupational setting.We conducted a prospective screening study over seven years in 1610 males with former occupational exposure to carcinogenic aromatic amines. Annual bladder cancer screening according to statutory requirements was offered. In addition to the regularly performed check for hematuria and urine cytology, the markers NMP22, UroVysion™ and survivin were performed in voided urine samples of the participants. Positive findings (not for survivin) were further followed through urethrocystoscopy.A total of 7219 urine samples were screened. During the study period 16 incidental and 4 recurrent bladder tumours, thereof three papillomas, occurred in a total of 19 participants. 14 out of twenty tumours were marker-positive, and all but two were early stage findings. Cell-based markers (cytology, UroVysion™) und molecular markers (NMP22, survivin) were largely complementary, thus acting as a "multi-marker panel". Eight of the tumours were identified by a positive cytology. Six tumours were not detected by any of the tumour markers. The results will be further evaluated through the inclusion of confounding factors, which have so far rarely been examined in other studies. This may lead to the development of tiered diagnostic strategies with the aim to reduce the number of invasive diagnostic procedures in the future.

The results of detailed analyses of the samples discussed in part I are reported. The chemical, morphological and microstructural changes which occurred during moist curing and soaking have been determined using thermal analysis, X-ray powder diffraction analysis, and scanning and transmission electron microscopy combined with EDAX. The analytical results together with the physical observations have shown that the period of volume instability and swelling coincides with the period of gypsum consumption and ettringite formation. However, swelling is not caused by growth of crystalline ettringite but is the result of water absorption. An osmotic mechanism is proposed in which concentration gradients are generated within a surface colloidal layer on the clay particles. Ettringite rods nucleate and grow within this layer and C-A-S-H gel is produced in the areas between the rods. This results in concentration gradients at the clay particle surfaces which provide the driving force for osmosis. The implications of these findings are discussed in relation to lime- stabilization of soils.

In the late 1950s the inbred polydipsic mice, STR/N, was discovered. The early studies indicated that the extreme polydipsia was not due to a lack of vasopressin but probably due to innate thirst of unknown origin. Because the recent investigation has revealed the presence of some functional abnormality in the brain of the STR/N mouse, we now investigated, using immunohistochemical techniques, distribution of vasopressin (AVP)- and oxytocin (OXT)-containing neurones in the hypothalamus of polydipsic strain of mouse and compared with that of the control. The pattern of distribution of AVP- and OXT-immunoreactive neurones in the paraventricular (PV), supraoptic (SO), and suprachiasmatic nuclei (SCN) of the STR/N polydipsic mouse was similar to that of the control, but the number of AVP-immunoreactive neurones was more numerous in the PVN and SON and less in the SCN in the polydipsic mouse than in the control. In addition, a discrete group of AVP- and OXT-containing neurones that was not clearly seen in the control was discovered in the STR/N. These results implicate that abnormal distribution in the brain AVP and OXT contribute to the mechanism responsible for the polydipsia shown by the strain STR/N.