Significance of soil moisture on temperature dependence of Hg emission.

Soil moisture is a key factor for mercury (Hg) emission from soil. Despite its significance for Hg emissions, the effect of soil moisture on Hg flux and fractions has not been thoroughly investigated. The objective of this study was to elucidate the influences of soil moisture and temperature on Hg fluxes from soils and Hg fractions. A kinetic study was performed to measure Hg emission fluxes of six soil samples under different temperature (T) (15 °C, 20 °C, 25 °C, 30 °C, and 35 °C) and moisture conditions (0%, 10%, and 20% added water). The results showed that the Hg fluxes increased with increases in T and soil moisture. A linear correlation was found between ln (Hg emission flux) and 1/T for the six soil samples at different moisture contents (R2 = 0.73-0.99). The range of activation energy (Ea) values was 25.31-57.86 kJ/mol. The Hg fractions in soils of different moisture content were determined by a sequential extraction method. The results demonstrated that soil moisture affected the Hg fractions in soils. The Ea values had different relationships with soil moisture in different soils. There were correlations between Ea and the elemental and mercuric sulfide fractions for air-dried soils. However, for moist soils, Ea was negatively correlated with the water-soluble and acid-soluble fractions. Collectively, the combination of the Hg emission kinetics and Hg fraction measurement of different moist soils indicated that Hg emission was affected by both total Hg concentration and Hg fractions.

Effects of N loading rate on CH4 and N2O emissions during cultivation and fallow periods from forage rice fields fertilized with liquid cattle waste.

The use of liquid cattle waste (LCW) as a fertilizer for forage rice is important for material recycling because it can promote biomass production, and reduce the use of chemical fertilizer. Meanwhile, increase in emission of greenhouse gases (GHGs), especially CH4 and N2O would be concerned. We conducted a field study to determine the optimum loading rate of LCW as N to promote forage rice growth with lower GHG emissions. The LCW was applied to forage rice fields, N100, N250, N500, and N750, at four different N loading rates of 107, 258, 522, and 786 kg N ha(-1), respectively, including 50 kg N ha(-1) of basal chemical fertilizer. The above-ground biomass yields increased 14.6-18.5 t ha(-1) with increases in N loading rates. During the cultivation period, both the CH4 and N2O fluxes increased with increases in LCW loading rates. In the treatments of N100, N250, N500, and N750, the cumulative CH4 emissions during the entire period, including cultivation and fallow period were 29.6, 18.1, 54.4, and 67.5 kg C ha(-1), respectively, whereas those of N2O were -0.15, -0.02, 1.49, and 5.82 kg N ha(-1), respectively. Considering the greenhouse gas emissions and above-ground biomass, the yield-scaled CO2-equivalents (CO2-eqs) were 66.3, 35.9, 161, and 272 kg CO2 t(-1) for N100, N250, N500, and N750, respectively. These results suggest that N250 is the most appropriate LCW loading rate for promoting forage rice production with lower GHG emissions.

Low serum neutrophil count predicts a positive prostate biopsy.

BACKGROUND: Asymptomatic prostatic inflammation may cause increased PSA in some men, leading to unnecessary prostate biopsy. We investigated whether the differential white cell count could predict the result of prostate biopsy. METHODS: Prostate needle biopsy was carried out in 323 Japanese men with elevated PSA levels or abnormal digital rectal findings. White blood cell count (WBC), differential white cell count (neutrophils, lymphocytes, basophils, eosinophils, and monocytes), and serum C-reactive protein level were assessed for associations with biopsy findings. RESULTS: In all, 203 (62.1%) were positive for prostate cancer. WBC, neutrophil count, age, PSA, prostate volume, and PSA density (PSAD) were associated with the results of biopsy (P<0.05). Multivariate analysis showed that neutrophil count, age, PSA, prostate volume and PSAD were independent predictors. When the cut-off neutrophil count was set at 2900 µl(-1), 78 of 104 men (75.0%) with a count below this value had a positive biopsy, while 125 of 219 (57.0%) men with a count above this value were positive. The area under the receiver-operator characteristics curve (AUC) for the predicted probability of a positive biopsy for prostate cancer according to the optimum logistic model was 0.83 (95% confidence interval (CI) 0.78-0.87), while the AUC for PSA was 0.70 (95% CI 0.64-0.76) and that for PSAD was 0.79 (95% CI 0.74-0.84). CONCLUSIONS: An elevated neutrophil count may be a good indicator of a benign prostate biopsy. Men with a low neutrophil count and an increase of serum PSA should strongly be considered for biopsy.

Polyphenols and fatty acids responsible for anti-cyanobacterial allelopathic effects of submerged macrophyte Myriophyllum spicatum.

Myriophyllum spicatum is known to inhibit the growth of cyanobacteria such as Microcystis aeruginosa by releasing anti-cyanobacterial allelochemicals. The allelochemicals possibly responsible for the inhibition include five polyphenols and three fatty acids, but the extent to which these are indeed responsible for the anti-cyanobacterial effects is unclear. The goal of this research was to determine the contribution of these compounds to the allelopathic effect of M. spicatum on M. aeruginosa. We first collected information on the release rates of these compounds and then added the compounds to a cyanobacterial medium on the basis of their release rates so as to simulate their excretion by M. spicatum. Addition of the polyphenols and fatty acids inhibited the growth of M. aeruginosa, and the interaction of the polyphenols and fatty acids was additive. The EC50 of a polyphenol and fatty acid mixture was compared with that of M. spicatum itself as previously determined in a mixed culture system in which M. spicatum and M. aeruginosa were incubated. The former was about 1.9 times higher than that of the latter, the implication being that the inhibitory effect of the polyphenols and fatty acids contributed about 53% of the allelopathic effect of M. spicatum. This paper is the first to describe allelochemicals that account for a half of the anti-cyanobacterial allelopathic effect of a macrophyte.

Prevention of lead leaching from fly ashes by mechanochemical treatment.

Fly ashes from a municipal solid waste incinerator were subjected to mechanochemical (MC) treatment in a planetary ball mill, and the treated fly ashes were cemented with a binder. The leachability of lead (Pb) from the treated fly ashes and from the cement product were investigated, and the speciation of lead in the treated and untreated ashes was determined by X-ray absorption fine structure (XAFS) analysis. MC treatment of the fly ashes and subsequent cementation prevented Pb leaching by 99.9%, whereas MC treatment alone prevented Pb leaching by 92.8%. Analysis of the X-ray absorption near-edge spectrum of the untreated fly ashes revealed that the predominant Pb species in the ashes was PbCl(2). In contrast, the counterpart in the treated fly ashes was Pb(3)O(4) insoluble in water. The formation of a species of Pb with a lower solubility in water than that of PbCl(2) was confirmed by MC treatment of PbCl(2)-spiked fly ashes for 48h, indicating the reduction of PbCl(2) in the spiked fly ashes to Pb via Pb(3)O(4) during MC treatment. Our results indicate that such reduction to an insoluble species prevented Pb from leaching and that MC treatment followed by cementation is a feasible method for the recycling of fly ashes.

Evaluation of ethanol washing on dioxins-polluted soil and sediment based on adsorption relationships.

Multi-stage ethanol washing on dioxins-polluted soil and sediment were performed. The results indicated the existence of limit washing concentration (LWC), where no more dioxins were removed from the soil or the sediment by further washing. In each stage, dioxins concentration in the soil, sediment and ethanol could be described satisfactory by the Freundlich equation. The Freundlich capacity factor, K(ef) correlated with the LWC which was estimated to be ca. 1000 pmol g(-1) in the case of soil, and about 150 pmol g(-1) in the case of sediment. Organic contents in the soil and sediment affected the Freundlich intensity parameter, n(-1) but not K(f). A model, which enables the calculation of removal efficiency of PCDD/DFs at each stage using K(f), n, and initial PCDD/DFs concentration, is presented.

Microbial degradation of estrogens using activated sludge and night soil-composting microorganisms.

In order to investigate the potential for microbial degradation of estrogens, and the products formed, activated sludge collected from Korea (ASK) and night soil-composting microorganisms (NSCM) were used to degrade estrogens. Results showed that both ASK and NSCM degraded almost 100% of the natural estrogens estrone (E1), 17beta-estradiol (E2), and estriol (E3) from initial concentrations of 20-25 mg/L, while synthetic estrogen, ethynylestradiol (EE2), was not degraded. Analysis of degradation products of E2 by using HPLC-ECD and a consecutive first-order reaction calculation confirmed that E2 was sequentially degraded to E1, which was further degraded to other unknown compounds by ASK and NSCM. We then used the yeast two-hybrid assay to show that the unknown degradation products did not appear to possess estrogenic activity when E1, E2 or E3 were degraded to below the detection limit after 14 days of incubation, indicating that ASK and NSCM not only degrade natural estrogens, but also remove their estrogenic activities.

The characteristics of the bacterial community structure and population dynamics for phosphorus removal in SBR activated sludge processes.

The characteristics of the bacterial community structure and population dynamics for phosphorus removal in activated sludge were investigated using laboratory-scale sequencing batch reactor (SBR) activated sludge processes fed with four different carbon sources. Phosphorus removal activity, quinone profile of the activated sludge and isolated bacterial strains were monitored. An enhanced phosphorus removal activity was accompanied by the increase in ubiquinone-9 (Q-9). The relationships between phosphorus removal activity and Q-9 contents of the isolated bacterial strains were dependent neither on the organic substrates nor on the species of isolated bacterial strains. The enhanced phosphorus removal capability of activated sludge seemed to be due to the increase in the populations of bacteria with activity of phosphorus removal, i.e. species succession of bacteria in activated sludge ecosystems, rather than the increase in the phosphorus removal capability of phosphorus removal bacteria. Not only Acinetobacter but also Pseudomonas identified from isolated strains were regarded as representative polyphosphates-accumulating organisms and predominant species to the whole of bacterial population in activated sludge for phosphorus removal.

Isolation and characterization of the ethynylestradiol-biodegrading microorganism Fusarium proliferatum strain HNS-1.

We cultivated hundreds of sediment, soil, and manure samples taken from rivers and farms in a medium containing ethynylestradiol (EE2) as the sole source of carbon, so that microorganisms in the samples would acclimatize to the presence of EE2. Finally, we isolated an EE2-degrading microorganism, designated as strain HNS-1, from a cowshed sample. Based on its partial nucleotide sequence (563 bp) of the 28S rRNA gene, strain HNS-1 was identified as Fusarium proliferatum. Over 15 days, F. proliferatum strain HNS-1 removed 97% of EE2 at an initial concentration of 25 mg.L-1, with a first-order rate constant of 0.6 d-1. Unknown products of EE2 degradation, which may be more polar compounds that have a phenolic group, remained in the culture medium.

[Clinical efficacy of treatment with low-dose flutamide in maximum androgen blockade therapy].

To prevent treatment withdrawal due to flutamide-induced liver dysfunction, we performed maximum androgen blockade (MAB) therapy by combining a luteinizing hormone-releasing hormone agonist or orchiectomy with low-dose flutamide (125 mg x 2/day) in patients with prostate cancer. In this study, the efficacy, adverse effects such as hepatotoxicity, and compliance were compared retrospectively between 35 patients who received low-dose flutamide therapy (1995-1999) and 27 patients who received flutamide at its ordinary dose (125 mg x 3/day). No significant difference was observed in the response rate (> or = PR) as determined from the prostate-specific antigen parameter (p = 0.6211) or the incidence of hepatotoxicity based on the aspartate aminotransferase and alanine aminotransferase levels. However, flutamide withdrawal due to liver dysfunction was less frequent in the low-dose group (2.9%) than in the ordinary dose group (18.5%) (p = 0.0386). MAB therapy using low-dose flutamide is expected to prevent the reduction in the compliance due to side effects and to improve the long-term prognosis in patients with prostate cancer, who are mostly elderly individuals.

Fenton oxidation of ethanol-washed distillation-concentrated benzo(a)pyrene: reaction product identification and biodegradability.

After multiple ethanol washings followed by distillation, concentrated benzo(a)pyrene (B(a)P) in ethanol (approximately 85 mg L(-1)) was treated by Fenton oxidation, where > 99.8% of B(a)P was removed under a pseudo-first-order reaction. GC-MS and HPLC analysis identified B(a)P-1,6-, -3,6-, and -6,12-dione as Fenton oxidation products; all of which are known to have lower toxicity than B(a)P. Microbial resistance experiments demonstrated that B(a)P-1.6-, -3.6-, and -6,12-dione are more easily degraded than B(a)P. These results indicate that the proposed treatment can be effectively applied to remediate B(a)P-contaminated soil.

Algal growth inhibition effects and inducement modes by plant-producing phenols.

Evaluated here are the inhibitory effects on blue-green algae (Microcystis aeruginosa) produced by nine plant-producing phenols (caffeic, p-coumaric, ferulic, protocatechuic, sinapic, syringic, and vanillic acids, catechol, and hydroquinone), two plant-produced acids (quinic and shikimic acid), phenol, resorcinol, hydroxy hydroquinone, and phloroglucinol. Algal assays confirmed growth inhibition of M. aeruginosa by polyphenols, i.e., caffeic/protocatechuic acid, catechol, hydroquinone, hydroxy hydroquinone, and phloroglucinol, and by phenols containing methoxy groups, i.e., vanillic, sinapic, and syringic acids. Accordingly, this indicates good feasibility for controlling growth of M. aeruginosa using such plant-producing polyphenols and/or phenols as additives. A comparison of the inhibitory effects of the polyphenols showed that those induced by polyphenols in which phenolic hydroxy groups bound a benzene ring at ortho- and/or para-positions to another phenolic hydroxy group are stronger than the effects induced by polyphenols in which phenolic hydroxy groups are at only meta-positions. Experiments showed that the only polyphenols demonstrating significant growth inhibition of M. aeruginosa were autoxidized. These results suggest that autoxidation of the polyphenols induces inhibitory effects by producing polyphenol-autoxidized products such as radicals.

A hybrid fenton oxidation-microbial treatment for soil highly contaminated with benz(a)anthracene.

In order to mitigate the strong microbial resistance of benz(a)anthracene [B(a)A] in soil, a hybrid treatment of Fenton oxidation followed microbial culture was carried out. Based on optimal Fenton oxidation. i.e., 1.0 ml of ethanol, 0.2 ml of 0.5 M Fe2+, and 0.3 ml of 30% H2O2 per 1 g of 500 mg B(a)A/kg soil, about 43% of B(a)A-7,12-dione was generated during oxidation of 97% B(a)A. When the comparative biodegradability between B(a)A-contaminated soil and B(a)A-contaminated soil after Fenton oxidation was examined, it was found that 98% of B(a)A-7,12-dione degraded after 63 d in comparison with only 12% of B(a)A over the same period; results demonstrating that Fenton oxidation enhances biodegradability of B(a)A through B(a)A-7,12-dione.

Photocatalytic degradation of gaseous perchloroethylene: products and pathway.

Batch photocatalytic degradation of 1000-ppm gaseous perchloroethylene (PCE) was conducted with UV irradiation such that nearly 100% was decomposed within 10 min. The main intermediate and final product were identified as trichloroacetylchloride (TCAC) and hydrogen chloride (HCl), respectively, and minor ones as dichloroacetic acid (DCAC), monochloroacetic acid (MCAC), carbon tetrachloride, chloroform, and phosgene. More than 90% of Cl- equivalent, i.e., the sum of the chlorine number in PCE, intermediates, and HCl, was compensated for during the time of PCE degradation; a result indicating that no other major chlorinated intermediates are present during the time of PCE degradation. In a similar experiment, 500 ppm of gaseous TCAC degraded into HCl within 3 h without producing DCAC or MCAC, where like PCE, more than 90% of Cl- equivalent, i.e., the sum of the chlorine number in TCAC and HCl, was compensated for during time of TCAC degradation. Accordingly, gaseous PCE is concluded to predominantly follow a degradation pathway of PCE --> TCAC --> HCl.

Prediction of Fenton oxidation positions in polycyclic aromatic hydrocarbons by Frontier electron density.

Five recalcitrant polycyclic aromatic hydrocarbons (PAHs) in ethanol were subjected to Fenton oxidation, and following GC-MS identification of respective oxidation products, their oxidation positions were compared to those predicted by Frontier electron density. Quinone forms of oxidation products were identified in each PAH. With the exception of fluorene, oxidation positions of quinone forms of products of acenaphthylene, anthracene, benz(a)anthracene, and benzo(a)pyrene corresponded with predicted positions in which Frontier electron density was high. From these results, it appears that determining the Frontier electron density of a PAH is a promising method for predicting the Fenton oxidation position.

Removal and decomposition of malodorants by using titanium dioxide photocatalyst supported on fiber activated carbon.

Effective and compact deodorization systems have been required for the measure of small-scale emission sources of offensive odors usually found in urban areas. We have developed a sheet material with titanium dioxide (TiO2) photocatalyst supported on fiber activated carbon (FAC) for a compact deodorization system. In the deodorization system using the TiO2/FAC sheet and a ultraviolet lamp, malodorants can be collected on the TiO2/FAC sheet by adsorption and then decomposed by photocatalysis with UV-irradiation. In this study, we obtained basic information about the removal and the decomposition of malodorants in the photocatalytic deodorization system using the TiO2/FAC sheet. The malodorants used in this study were methyl mercaptan, ammonia, and hydrogen sulfide. In addition, two kinds of light sources, a black light bulb (BLB; dominant wavelength: 365 nm) and an ultraviolet germicidal lamp (UV2; dominant wavelength: 254 nm) were used to analyze the effect on removal and decomposition characteristics by different dominant wavelengths. The removal rates of malodorants from the gas phase were determined in the deodorization system in the presence or absence of the TiO2/FAC sheet and UV-irradiation in order to study each removal effect due to adsorption onto the TiO2/FAC sheet, direct photolysis by UV-irradiation, and photocatalytic decomposition. The effect of adsorption onto the TiO2 /FAC sheet was pronounced in this batch-type experiment. The effect of photocatalysis was observed from the removal rates of methyl mercaptan. The percent oxidation of ammonia to nitrate and that of methyl mercaptan to sulfate were examined by determining products, i.e. nitrate and sulfate ions, with purified water after the reaction. The formation of nitrate or sulfate was not observed without UV-irradiation using the BLB, while the reactions progressed in the presence of the TiO2/FAC sheet. When the UV2 lamp was used, the oxidation of methyl mercaptan to sulfate occurred without the TiO2/FAC sheet. This suggests that the decomposition characteristics of malodorants were dependent on the wavelength of the light source.

[ACTH-independent bilateral macronodular adrenocortical hyperplasia (AIMAH): a case report].

We report a case of adrenocorticotropic hormone (ACTH)-independent macronodular adrenocortical hyperplasia (AIMAH). A 54-year-old Japanese man was admitted to our hospital for further examination of obesity and hypertension. Endocrinological studies showed that plasma cortisol was high (22.5 micrograms/dl) without diurnal rhythm, and plasma ACTH was low. Two or 8 mg of dexamethasone did not suppress the plasma cortisol levels. Abdominal computed tomography revealed nodular hyperplasia of bilateral adrenal glands. Adrenal scintigraphy showed the positive uptake of 131I-adosterol to bilateral adrenal glands. Brain magnetic resonance imaging revealed no abnormalities. He was diagnosed as having Cushing's syndrome with bilateral adrenal hyperplasia, and bilateral adrenalectomy was performed. Left and right adrenal glands were 52 g and 35 g, respectively, and were occupied by yellow nodular lesions. Histologically, hyperplastic lesions were composed of clear cells. Finally he was diagnosed with AIMAH.

Treatment of PCB-contaminated soil in a pilot-scale continuous decomposition system.

The BCDP (Base Catalyzed Decomposition Process) is a process by which difficult-to-decompose organic chlorine compounds, such as PCBs, are chemically decomposed and dechlorinated. Pilot-plant tests for PCB contaminated soil were carried out. PCB contaminated soil (32 mg/kg-530 mg/kg) was decontaminated to a level (0.038 mg/kg-4.8 mg/kg) which satisfied the corresponding Japanese environmental standard which stipulates, "there must be no discharge of PCB containing leachate".

[Successful preoperative interferon-alpha therapy of renal cell carcinoma with tumor thrombus extending into the inferior vena cava--case report].

We report a case of renal cell carcinoma in whom preoperative interferon-alpha therapy was successful in reducing the primary lesion and the tumor thrombus extending into the inferior vena cava. A 67-year-old man was referred to our hospital because of his right renal mass. We made a diagnosis of a right renal tumor with tumor thrombus by imaging examinations. Because his performance status was 3, a radical operation was considered risky. So we started interferon-alpha therapy. Four months after the start of interferon-alpha therapy, the primary lesion and the tumor thrombus reduced in their size, and the clinical response was evaluated as partial response by the response criteria for urological cancer treatment. Because of improving the performance status and reducing the tumor size, radical nephrectomy and tumor thrombectomy could be performed. Pathological examinations revealed that viable renal cell carcinomas were found only in some small parts of the primary lesion, but not in the tumor thrombus. Postoperatively, no recurrence and metastasis of renal cell carcinoma of the patient have been detected in these two and a half years.

[The effect of hyaluronic acid on keratocyte proliferation].

Our previous study demonstrated that during healing of penetrating corneal incision, hyaluronic acid (HA) appears at the wound area with massive infiltration of activated keratocytes, suggesting a possible role of HA in keratocyte proliferation. In the present study, we investigated the effect of HA on keratocyte proliferation. A penetrating incision was made in the center of rabbit corneas. Wounded corneas were treated with HA eye drops or physiological saline every 2 hours for 24 hours. Then the corneas were excised, labeled with 3H-thymidine for 4 hours, and subjected to autoradiography. Rabbit keratocytes were cultured in chamber slides in TC199 medium alone or in TC199 containing HA for 24 hours, labeled with 3H-thymidine for 4 hours, and subjected to autoradiography. In the corneas treated with HA, the number of keratocytes incorporating 3H-thymidine was significantly higher than in the control corneas. The rate of 3H-thymidine uptake in keratocytes cultured with any concentration of HA was higher than that of the control. Both in vivo and in vitro studies demonstrated stimulatory effect of HA on keratocyte proliferation. It is possible that HA might promote corneal stromal wound healing by stimulating keratocyte proliferation.