FECAL CONTAMINATION AND THE PROPORTION OF HUMAN-ASSOCIATED E. coli ALONG NHUE RIVER, VIET NAM

According to rapid urbanization in Asian countries, the amount of domestic wastewater discharge has been increasing, resulted in water pollution and potential health risk on human. To secure biological safety of rivers, it is critical to understand the sources of contamination. The present study applied the human-associated E.coli genetic marker (H8) to characterize the source of microbial contamination. E. coli concentration and other pollutants indices were investigated at 10 sites along the river: S1 (upstream) – S10 (downstream). For 220 E. coli isolates collected from river water samples, Real-Time PCR was performed with H8. The results showed that organic pollutants peaked at the middle stream, although they were originally low at upstream (S1). The positive proportion of H8 with E. coli peaked at 40.9 % at middle stream (S6), which was significantly higher than S1 (4.5 %) (p = 0.012). This high proportion implied the relative dominance of human-associated E. coli, which were in line with a large inflow of sanitary wastewater in middle stream, indicated by land use along the river. Thus, we successfully demonstrated the usefulness of H8 to track the source of microbial contamination in the river.

FECAL CONTAMINATION AND THE PROPORTION OF HUMAN-ASSOCIATED E. coli ALONG NHUE RIVER, VIET NAM

According to rapid urbanization in Asian countries, the amount of domestic wastewater discharge has been increasing, resulted in water pollution and potential health risk on human. To secure biological safety of rivers, it is critical to understand the sources of contamination. The present study applied the human-associated E.coli genetic marker (H8) to characterize the source of microbial contamination. E. coli concentration and other pollutants indices were investigated at 10 sites along the river: S1 (upstream) – S10 (downstream). For 220 E. coli isolates collected from river water samples, Real-Time PCR was performed with H8. The results showed that organic pollutants peaked at the middle stream, although they were originally low at upstream (S1). The positive proportion of H8 with E. coli peaked at 40.9 % at middle stream (S6), which was significantly higher than S1 (4.5 %) (p = 0.012). This high proportion implied the relative dominance of human-associated E. coli, which were in line with a large inflow of sanitary wastewater in middle stream, indicated by land use along the river. Thus, we successfully demonstrated the usefulness of H8 to track the source of microbial contamination in the river.

Development and evaluation of dose calculation algorithm with a combination of Monte Carlo and point-kernel methods for boron neutron capture therapy

We developed a 'hybrid algorithm' that combines the Monte Carlo (MC) and point-kernel methods for fast dose calculation in boron neutron capture therapy. The objectives of this study were to experimentally verify the hybrid algorithm and to verify the calculation accuracy and time of a 'complementary approach' adopting both the hybrid algorithm and the full-energy MC method. In the latter verification, the results were compared with those obtained using the full-energy MC method alone. In the hybrid algorithm, the moderation process of neutrons is simulated using only the MC method, and the thermalization process is modeled as a kernel. The thermal neutron fluxes calculated using only this algorithm were compared with those measured in a cubic phantom. In addition, a complementary approach was used for dose calculation in a geometry simulating the head region, and its computation time and accuracy were verified. The experimental verification indicated that the thermal neutron fluxes calculated using only the hybrid algorithm reproduced the measured values at depths exceeding a few centimeters, whereas they overestimated those at shallower depths. Compared with the calculation using only the full-energy MC method, the complementary approach reduced the computation time by approximately half, maintaining nearly same accuracy. When focusing on the calculation only using the hybrid algorithm only for the boron dose attributed to the reaction of thermal neutrons, the computation time was expected to reduce by 95% compared with the calculation using only the full-energy MC method. In conclusion, modeling the thermalization process as a kernel was effective for reducing the computation time

Analysis of Clinical Outcome of Patients with Poorly Differentiated Thyroid Carcinoma

Background. We retrospectively analyzed whether poor differentiation is the independent prognostic factor for thyroid carcinoma or not. Methods. The subjects were 29 patients with PDTC who were treated between April 1996 and March 2006 to compare with those of well-differentiated papillary carcinoma patients (n = 227). Results. The relapse free (RFS), distant relapse-free survival and cause-specific survival, rates were significantly lower in patients with PDTC (P < .0001, P < .001, and P < .05). After classification into focal (<10%) and diffuse type (over 10%) of PDTC, there were no significant differences in RFS and cause-specific survival due to component type or proportion of poorly differentiated component. On multivariate analysis, poor differentiation (P < .0005, RR = 4.456, 95% CI; 1.953–10.167) and extrathyroidal infiltration (P < .05, RR = 2.898, 95% CI; 1.278–6.572) showed a significant impact on DFS, and poor differentiation (P < .05, RR = 9.343, 1.314–66.453) and age (P < .005, RR = 1.306, 1.103–1.547) significantly impacted cause-specific survival. Conclusion. Poor differentiation was an independent factor for survival. Distant relapse was significantly more common among PDTC patients, and systemic therapy might be warranted

validity of dietary diversity

The validity of dietary variety score (DVS) using a short-form questionnaire has not been investigated using dietary diversity based on a quantitative distribution of consumed foods in older Japanese. We examined the association between DVS and objective dietary diversity using a Quantitative Index for Dietary Diversity (QUANTIDD) based on the quantitative distribution of foods consumed by older Japanese community dwellers. The subjects were 65 older Japanese community dwellers aged 60–79 years. We used two kinds of scores for assessment of dietary diversity. At first, dietary diversity was determined using DVS calculated from answers to a questionnaire about frequencies of intake of 10 food groups. Second, dietary intake was assessed using a 3-day dietary record with photographs, and dietary diversity was determined using QUANTIDD. The relationships between DVS and QUANTIDD were assessed using partial correlation coefficients controlling for confounders. The correlation coefficient between DVS and QUANTIDD was moderate (r = 0.212-0.458). After controlling for confounders, those correlation coefficient between DVS and QUANTIDD remained moderate. The findings suggest that there was a moderate relationship between DVS and QUANTIDD, and DVS using a short-form questionnaire may be useful for assessing dietary diversity in older Japanese community dwellers

Oxidative Deamination Activity of EGCG

(-)-Epigallocatechin-3-O-gallate (EGCG), the most abundant polyphenol in green tea, mediates the oxidative modification of proteins, generating protein carbonyls. However, the underlying molecular mechanism remains unclear. Here we analyzed the EGCG-derived intermediates generated upon incubation with the human serum albumin (HSA) and established that EGCG selectively oxidized the lysine residues via its oxidative deamination activity. In addition, we characterized the EGCG-oxidized proteins and discovered that the EGCG could be an endogenous source of the electrically-transformed proteins that could be recognized by the natural antibodies. When HSA was incubated with EGCG in the phosphate-buffered saline (pH 7.4) at 37°C, the protein carbonylation was associated with the formation of EGCG-derived products, such as the protein-bound EGCG, oxidized EGCG, and aminated EGCG. The aminated EGCG was also detected in the sera from the mice treated with EGCG in vivo. EGCG selectively oxidized lysine residues at the EGCG-binding domains in HSA to generate an oxidatively deaminated product, aminoadipic semialdehyde. In addition, EGCG treatment results in the increased negative charge of the protein due to the oxidative deamination of the lysine residues. More strikingly, the formation of protein carbonyls by EGCG markedly increased its cross-reactivity with the natural IgM antibodies. These findings suggest that many of the beneficial effects of EGCG may be partly attributed to its oxidative deamination activity, generating the oxidized proteins as a target of natural antibodies

A combination of a DNA-chimera siRNA against PLK-1 and zoledronic acid suppresses the growth of malignant mesothelioma cells in vitro.

Although novel agents effective against malignant mesothelioma (MM) have been developed, the prognosis of patients with MM is still poor. We generated a DNA-chimeric siRNA against polo-like kinase-1 (PLK-1), which was more stable in human serum than the non-chimeric siRNA. The chimeric PLK-1 siRNA inhibited MM cell proliferation through the induction of apoptosis. Next, we investigated the effects of zoledronic acid (ZOL) on MM cells, and found that ZOL also induced apoptosis in MM cells. Furthermore, ZOL augmented the inhibitory effects of the PLK-1 siRNA. In conclusion, combining a PLK-1 siRNA with ZOL treatment is an attractive strategy against MM