Copper,zinc, and selenium in human blood and urine after injection of sodium 2,3-dimercaptopropane-1-sulfonate: a study on subjects with dental amalgam

This study investigated the effects of a single dose of intravenously administered sodium 2,3-dimercaptopropane-1-sulfonate (DMPS) on the essential elements copper, zinc, and selenium in human blood and urine. The possible role of dental amalgam was also addressed. Eighty individuals, divided in four groups according to the presence or absence of dental amalgam fillings and symptoms self-related to such fillings, were given DMPS (2 mg/kg body wt) and 500 mL Ringer’s acetate intravenously. Urine and blood were collected prior to the injection, and thereafter at intervals over a 24-h period. Cu, Zn, and Se concentrations were determined by atomic absorption spectrometry methods. A statistically significant increase in the concentrations of Cu and Zn in urine was observed 30 and 120 min after the DMPS injection compared to the preinjection concentrations. The concentrations of Se were not affected. The cumulated excretion over 24 h after DMPS injection constitutes only from 0.1% to 0.7% of the body content of these elements. There was no effect of different amalgam statuses on Cu and Zn excretion. We found a temporary decrease (4–7%) in the concentrations of Cu, Zn, and Se in blood 15 and 30 min after DMPS, but this seems to be the result of dilution factors. Administration of a single dose of DMPS does not affect the body stores of the essential elements Cu, Zn, and Se.     

Variations in the natural abundance of 15N in ryegrass/white clover shoot material as influenced by cattle grazing

Biological N2 fixation in clover is an important source of N in low external-N input farming systems. Using the natural 15N-abundance method, variations in N2 fixation were investigated in grazed and mowed plots of a ryegrass/white clover field. Ryegrass 15N varied considerably, from 0.2 to 5.6 under mowed conditions and from –3.3 to 11.6 under grazed conditions. Variations in 15N white clover were lower than in ryegrass, especially in the mowed plots (SE = 0.05, n = 20). The variations in the percentage of nitrogen derived from the atmosphere (%Ndfa) in white clover were highest in the grazed plots where it ranged from 12 to 96% (mean = 64%) compared with the mowed plots where it ranged from 64 to 92% (mean = 79%). Thus, the N2 fixation per unit white clover DM in the grazed ley was lower and more variable than under mowing conditions.Urine from dairy cows equivalent to 0, 200, 400 and 800 kg N ha-1 was applied to a ryegrass/white clover plot 6, 4 or 2 weeks before harvest. Without urine application 15N of ryegrass was positive. By increasing urine application (15N = –1) two weeks before sampling, the 15N of ryegrass decreased strongly to about –7 (P < 0.001). However, this effect was only observed when urine was applied two weeks before sampling. When applying 800 kg N four and six weeks before sampling, 15N in ryegrass was not significantly different from the treatment without urine application. White clover 15N was unaffected by whatever changes occurred in 15N of the plant-available soil N pool (reflected in 15N of ryegrass). This indicates that within the time span of this experiment, N2 fixation per unit DM was not affected by urine. Therefore, newly deposited urine may not be the main contributing factor to the variation in %Ndfa found in the grazed fields. This experiment suggested that the natural abundance method can be applied for estimating %Ndfa without disturbance in natural animal-grazed systems.     

Concentration compared with total urinary excretion of 11,17-DOA in cynomolgus monkey urine

Strees sensitive molecules exhibit great variation in concentration in the circulation and it may often be advantageous to quantify these in urine or feces rather than in serum or plasma. We advocate that all urine-or feces-should be collected, and that excretion of stress sensitive molecules should be expressed as amounts excreted per time unit per kg body-weight, rather than being expressed as concentrations in samples. Urine and feces excretion varies significantly within and between animals over time, which may render simple concentration measures of molecules of little biological relevance.     

Value of computer‐assisted quantitative nuclear morphometry for differentiation of reactive renal tubular cells from low‐grade urothelial carcinoma

H. Ohsaki, E. Hirakawa, K. Kagawa, M. Nakamura, H. Kiyomoto and R. Haba Value of computer‐assisted quantitative nuclear morphometry for differentiation of reactive renal tubular cells from low‐grade urothelial carcinoma Objective: To assess whether computer‐assisted quantitative morphological parameters can be an effective tool for objectively distinguishing reactive renal tubular cells from low‐grade urothelial carcinoma cells (LG‐UCs) in voided urine. Methods: Nuclear morphometry was performed by a computer‐assisted image analyser system on Papanicolaou‐stained cytological specimens. The circumference of reactive renal tubular cells (n = 40) or LG‐UC (n = 20) nuclei were manually traced, and the following nuclear morphometric parameters were analysed: (i) area, (ii) perimeter, (iii) roundness factor, (iv) maximum length, and (v) linear factor. For each nuclear measurement, we calculated the maximum, minimum, mean and standard deviation. Results: The mean nuclear area and nuclear perimeter were higher in reactive renal tubular cells compared to the LG‐UCs. The mean of roundness and linear factors (reflecting a tendency for the nuclear outline to be regular and oval, respectively) were higher in LG‐UCs compared with reactive renal tubular cells. Among nuclear areas, the nuclear perimeter, roundness factors and maximum length did not show any significant differences between reactive renal tubular cells and LG‐UCs. On the other hand, the linear factor showed a mean higher value among LG‐UCs than reactive renal tubular cells (P = 0.023). Conclusions: Of five quantitative nuclear morphological parameters, only linear factor was statistically significant in differentiating reactive renal tubular cells in renal disease from LG‐UCs.     

On-line chemiluminescence determination of mitoxantrone by capillary electrophoresis

A novel capillary electrophoresis (CE) with chemiluminescence (CL) detection method for the determination of mitoxantrone (MTX) has been developed, which based on the CL reaction of potassium ferricyanide with luminol in sodium hydroxide medium sensitized by MTX. Under optimum analytical conditions, MTX is determined over the range of 7.0 × 10⁻⁸–1.0 × 10⁻⁶ M with a detection limit of 1.0 × 10⁻⁸ M. The relative standard deviation (RSD) was 3.7%, 2.6% and 3.0% for 7.0 × 10⁻⁸, 5.0 × 10⁻⁷ and 1.0 × 10⁻⁶ M MTX (n = 11), respectively. In laboratory-built CE–CL apparatus, the proposed method has been applied to determination of MTX in commercial drug and spiked in human urine and plasma with satisfactory results.     

Can cytological features differentiate reactive renal tubular cells from low‐grade urothelial carcinoma cells?

H. Ohsaki, E. Hirakawa, Y. Kushida, S. Yokoshita, M. Nakamura, H. Kiyomoto and R. Haba Can cytological features differentiate reactive renal tubular cells from low‐grade urothelial carcinoma cells? Objective: To compare the cytomorphological and immunocytochemical features of reactive renal tubular cells and low‐grade urothelial carcinoma cells (LG‐UCs). Methods: We examined 15 cytological parameters in 38 cases with reactive renal tubular cells in renal disease and 20 cases of LG‐UCs from bladder cancer that had been diagnosed by histological examination. Voided urine cytological parameters evaluated were as follows: (i) maximum cell numbers of clusters, (ii) cannibalism, (iii) rosette‐like arrangement, (iv) hobnail‐shaped cells, (v) vacuolated cytoplasm, (vi) intracytoplasmic haemosiderin, (vii) irregular nuclear contours, (viii) chromatin pattern, (ix) prominent nucleoli, (x) cast encasement, (xi) casts, (xii) dysmorphic erythrocytes, (xiii) isomorphic erythrocytes, (xiv) necrosis, and (xv) vimentin reactivity. The above parameters were determined using Mann–Whitney U‐test and chi‐square test, with differences considered significant at P < 0.05. Results: In reactive renal tubular cells, low to moderate cell numbers of clusters (fewer than 50 cells), rosette‐like arrangement, hobnail‐shaped cells, vacuolated cytoplasm, intracytoplasmic haemosiderin, euchromatin pattern, prominent nucleoli, dysmorphic erythrocytes and vimentin reactivity were present in significantly higher proportions compared with those in LG‐UCs. In LG‐UCs, high cell numbers of clusters (50 cells or more), cannibalism, heterochromatin pattern, isomorphic erythrocytes and necrosis were seen in significantly higher proportions. No significant differences were observed in irregular nuclear contours, cast encasement or casts. Conclusions: Based on results of the present study, maximum cell numbers of clusters, cannibalism, rosette‐like arrangement, hobnail‐shaped cells, vacuolated cytoplasm, intracytoplasmic haemosiderin, chromatin pattern, prominent nucleoli, dysmorphic erythrocytes, isomorphic erythrocytes, necrosis, and vimentin reactivity were capable of distinguishing reactive renal tubular cells from LG‐UCs.     

Species-specific releaser effect of urine from ovulated female masu salmon and rainbow trout

MT (17α-methyltestosterone)-treated immature masu salmon Oncorhychus masou and rainbow trout Oncorhynchus mykiss , exposed to the urine of ovulated females in their non-reproductive season, made significantly more entries into the channel, of a Y-maze preference trough, conditioned by the urine of conspecific females than by heterospecifics. Immature, non-treated controls in both species showed no preference for the urine of ovulated females. These results suggest that, for both species, the releaser pheromones that attract males in the urine are species-specific. Therefore, utilization of species-specific chemical signals may be one of the mechanisms of the reproductive isolation in Oncorhynchus species.     

Expression of cytokeratin 20 in urine cytology smears: a potential marker for the detection of urothelial carcinoma

BACKGROUND: Urine cytomorphology is one of the oldest methods for screening and monitoring patients with transitional cell carcinoma (TCC). Sensitivity of urine cytology is relatively low. Ancillary techniques on urine sample may increase the sensitivity. AIM: To explore the utility of cytokeratin 20 (CK20) immunostaining in identifying malignant cells in urine cytology smears. MATERIALS AND METHODS: Fourteen cases each of confirmed TCC and benign urinary cytology along with five cases of atypical cells in urine were immunostained with a monoclonal CK20 antibody. Of 14 cases of TCC, 12 showed strong positive staining with the antibody. All benign cases were negative except for a few cases in which the umbrella cells were weakly to moderately positive. In all five cases of atypical urine cytology the atypical cells stained positive with the antibody. These cases were later confirmed as TCC on histopathology of bladder wall biopsy. CONCLUSION: CK20 is an important biomarker that can be used to identify TCC in urine cytology smears. It is particularly useful in those cases where malignancy cannot be confirmed by morphology alone.     

Determination of free and total S-phenylmercapturic acid by HPLC/MS/MS in the biological monitoring of benzene exposure

Urinary S-phenylmercapturic acid (SPMA) is a biomarker suggested by the American Conference of Governmental Industrial Hygienists (ACGIH) for assessing occupational exposure to benzene. A possible cause of the miscorrelation between environmental monitoring and biological monitoring for benzene exposure, which many authors complain about, is the existence of a urinary metabolite that turns into SPMA by acid hydrolysis. Forty urine samples were tested to determine which concentration value would correspond to the ACGIH Biological Exposure Index (BEI) of 25 µg g^-1 creatinine if exposure assessment was based on the determination of SPMA after quantitative hydrolysis of its precursor. An aliquot of each sample was hydrolysed with 9 M H₂SO₄, a second one was brought to pH 2 and a third one was used as it was (free SPMA). SPMA was determined by high-performance liquid chromatography/tandem mass spectrometric technique (HPLC/MS/MS) using an internal standard. The analytical method was validated in the range 0.5-50 µg l^-1. The average SPMA in pH 2 samples is 45-60% of the total, while free SPMA varies from 1% to 66%. The hydrolysis of pre-SPMA reduces the likelihood of variability in the results by reducing pH differences in urine samples and increasing the amount of measured SPMA. The BEI limit value would be about 50 µg g^-1 creatinine.