• Resources Recycling
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• v.5 no.1
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• pp.29-33
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• 1996

The cominnn plocesses lor rccoremg silver irom silvcr conlaincd waster are the lcachmg silver hy HNO;. the srlcctive precipilillion of sliver ion lo AgCl and thc rcduchon of Ag wrfh ;I proper reductant. In this sludy, thc reduction of AgCI lo Ag was invesllngated by using Na, CO, as a rcd\icta~lt. The variations wcic reaction time. ttmpcrarure thc amount of NalCO, . and the resulls %, ere analyzcd by using sialist~c:d tecl~niques such as the ]polynomial rcgressiun analysis and the response surh~ce method. More than Yh% Ag analyzed was rcduced 1rtm AgCI at 62UT. I hour ullder condillon of 2 stnlchio~nctric ratio of Na iCO, !AgCI.

• Journal of Preventive Medicine and Public Health
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• v.35 no.2
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• pp.129-135
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• 2002

Objective : The primary objective of this study was to estimate the prevalence of HBsAg-positives in the late 1990's among Korean adults. In addition, we evaluated the association of age, a residential area, a vaccination rate, a family history of chronic liver diseases and a past history of acute liver disease with the seropositivity of HBsAg, and estimated the prevalence of chronic HBV infection by follow-up for 6 month or more. Methods : A total of 10 areas, six metropolitan and four small cities, were selected. In each cities, one health screening center was selected for recruitment of study subjects. The study subjects were enrolled from a general health examination program that is provided by medical insurance companies. Questionnaires on various risk factors were administered to the study subjects. Sera was drawn and tested for HBsAg by radioimmunoassay. HBeAg and ALT were also tested for those of HBsAg positive. The HBsAg positives was retest for HBsAg 6 months later Results : Among the study subjects (n= 1816), the seroprevalence of HBsAg was 5.5% (95% CI=4.5%-6.6%), 7.4% in men (95% CI=5.8-9.4) and 3.6% in women (95% CI=2.5-5.0). A past history of acute liver disease and a family history of chronic liver diseases was shown to be risk factors for HBsAg positivity. Among the 31 HBsAg-positives, negative seroconversion rate was estimated to be 3.2%, Thus, prevalence of chronic HBV infection was estimated to be 5.3% (95% CI=3.7-6.6). Conclusion : In this study, the HBsAg seroprevalence rate was lower than that of the other studies in 1980's, particularly in young adult and women. Considering the public health importance of liver cancer and chronic liver diseases, the further effort is needed to prevent and reduce the HBV infection.

• Journal of Environmental Health Sciences
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• v.39 no.4
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• pp.369-375
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• 2013

Objectives: This study was conducted to identify factors determining the toxicity of manufactured silver nano-particles (AgNPs) on aquatic organisms. Methods: For this purpose, we prepared several AgNPs with varied characteristics, including hydrodynamic size (nano-$^{ABC}Ag^{Cit}\;vs$-sized-$^{ABC}Ag^{Cit}$), impurities ($^{ABC}Ag$ stock vs $^{ABC}Ag$), and citrate capping ($^{ABC}Ag^{Cit}$), using a commercially available manufactured AgNP ($^{ABC}Ag$ stock). Acute tests were conducted using larval zebrafish (Danio rerioI). In addition, in order to determine the ecotoxicological potentials of various capping agents, toxicity tests were conducted with microbes, waterfleas, and fish for eight different capping agents that are used for NPs. Results: The toxicity of AgNPs in terms of 96 h fish $LC_{50}$ increased in the following order: $^{ABC}Ag$ stock < $^{ABC}Ag=^{ABC}Ag^{Cit}=nano-^{ABC}Ag^{Cit}$ < ${\mu}$-sized-$^{ABC}Ag^{Cit}$ < $AgNO_3$. After removing impurities by dialysis, 96 h $LC_{50}$ value decreased significantly from $126.6{\mu}g/L$ (95% confidence intervals [CI]: 107.0-146.2) ($^{ABC}Ag$ stock) to $78.6{\mu}g/L$ (CI: 72.7-84.8) ($^{ABC}Ag$). For ${\mu}$-sized-$^{ABC}Ag^{Cit}$ (ranging between 3.9 and 40.6 nm) and $^{ABC}Ag^{Cit}$ (40.6 nm and $9.1{\mu}m$), the 96 h $LC_{50}$ of the former ($43.9{\mu}g/L$, CI: 36.0-51.7) was approximately two-fold lower than that of the latter ($87.0{\mu}g/L$, CI: 73.5-100.3). Conclusions: In this study, we found that for acute lethality, the contribution of impurities and particle size was significant, but that of citrate was negligible.

• Journal of Preventive Medicine and Public Health
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• v.30 no.1 s.56
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• pp.1-15
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• 1997

To investigate the association between hepatocellular carcinema(HCC) and infection of hepatitis B virus(HBV) and hepatitis C virus(HCV) in an HBV endemic area, a case-control study of 254 patients with HCC and of 1,270 age and sex matched health control subjects was done. Among the 254 HCC patients 166(65.4%) were positive for hepatitis B surface antigen(HBsAg), 49(19.3%) were positive for HCV antibody (anti-HCV Ab). The crude odd ratio of patients with HBsAg was 36.1(95% CI :22.4-58.2) and with anti-HCV Ab was 9.0(95% CI :5.5-14.6). In an analysis, which HBsAg(-), HBcAb(-), anti-HCV Ab(-) group was chosen as referent group, odd ratio of HBsAg(+) group was 14.4(95% CI: 7.2-28.9) and of anti- HCV Ab(+) was 10.7(95% CI: 2.9-40.0). odd ratio of anti-HCV Ab(+), HBsAg(+) group and anti-HCV Ab(+), HBsAg(-), HbcAb(+) group for HCC were elevated to 27.3(95% CI : 9.0-82.9), 15.9(95% CI:7.1-35.8) respectly, The odd ratio of anti-HCV Ab(-), HBsAg(-), HBcAb(+) group was 2.4(95% CI : 1.1-5.0). These result suggested that HBV and HCV were associated with HCC. In HBV endemic area patients with HBcAb alone should be considered risk group for HCC.

• Journal of Powder Materials
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• v.11 no.6 s.47
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• pp.477-485
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• 2004

Monodispersed flaky silver powder was obtained by controlling the ratios of $H_{2}O_{2}/NH_{3}$ and Agin in a mixed solution of ethylene glycol and ammonia with an addition of PVP. The effects of $NH_{3}/Ag,\; H_{2}O_{2}/Ag\;and\;H_{2}PtCl_{6}/Ag$ on its morphology and size were investigated. In $H_{2}O_{2}-NH_{3}-AgNO_{3}\;system,\;NH_{3}/Ag$ molar ratio was found to be an important reaction factor for the nucleation and crystal growth of Ag powder. The synthesis of flaky powder was optimized at over 6 of $NH_{3}/Ag \;and\;5\;of\;H_{2}O_{2}/Ag\;under\;1.0{\times}10^{-3}\;of\;Pt/Ag.\;Moreover,\;as\;the\; NH_{3}/Ag$ molar ratio increased, the size of precipitates was increased regardless of the amount of Pt. In the absence of $H_{2}PtCI$, the morphology and size of reduced Ag powder were found to be irregular in shape $2-4{\mu}m$ in diameter. However, homogenized fine Ag powder was obtained due to heterogeneous nucleation when $H_{2}PtCI$ used as a cat-alyst, and flaky one was synthesized with the addition of Pt over $1.0{\times}10^{-3}$ of Pt/Ag.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6207-6210
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• 2012

Introduction: Although a number of studies were published in the past several years on associations between hsa-mir-27a and cancer risk, the findings remain conflicting rather than conclusive. To derive a more precise effect on the association between SNP hsa-mir-27a rs895819 and breast cancer risk, we conducted a meta-analysis for the first time. Materials and Methods: Through retrieval from PubMed for the period up to August 2012, a total of four studies were identified with 3,287 cases and 4,298 controls for SNP hsa-mir-27a rs895819. We calculated summary odds ratio (ORs) and corresponding 95% confidence intervals (CIs) using a fixed effects model (when the heterogeneity was absent, P>0.10). Otherwise, the random-effects model was used. Results: We found that hsa-mir-27a rs895819 polymorphism also did not reveal any relationship with breast cancer susceptibility (AG versus AA: OR = 0.98; 95%CI, 0.73-1.32; GG versus AA: OR = 0.86; 95% CI, 0.72-1.03; AG/GG versus AA: OR = 0.92; 95% CI, 0.74-1.14), while significantly decreased risk was found among Europeans in AG versus AA and AG/GG versus AA models tested (AG versus AA: OR = 0.83; 95%CI, 0.72-0.97; GG versus AA: OR = 0.86; 95% CI, 0.71-1.05; AG/GG versus AA: OR = 0.84; 95% CI, 0.75-0.94). Conclusion: These findings suggest that hsa-mir-27a rs895819 polymorphism may play an important role in breast cancer development.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2517-2522
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• 2014

Background: Several recent studies have explored associations between pre-mir-218 polymorphism (rs11134527) and cancer risk. However, published data are still inconclusive. To obtain a more precise estimation of the relationship in the Chinese population, we carried out a meta-analysis for the first time. Materials and Methods: Through retrieval from the PubMed, Medline, Embase, Web of Science databases, China National Knowledge Infrastructure and the Chinese BioMedical Literature Database, a total of four studies were analyzed with 3,561 cases and 3,628 controls for SNP pre-mir-218 rs11134527. We calculated odds ratios (ORs) and 95% confidence intervals (95%CIs) to explore the strength of associations. Results: The results showed that the rs11134527 polymorphism was associated with decreased cancer risk in GG versus AA and GG versus AA+AG models tested ( GG vs AA: OR=0.82, 95%CI: 0.71-0.94; GG vs AA+AG: OR=0.84, 95%CI: 0.74-0.96), and significantly decreased cervical cancer risk was observed in GG versus AA and GG versus AA+AG models (GG vs AA: OR=0.79, 95%CI: 0.66-0.94; GG vs AA+AG: OR=0.80, 95%CI: 0.68-0.94). However, no significant association between the rs11134527polymorphism and hepatocellular carcinoma risk was observed in all comparison models tested (AG vs AA: OR=0.94, 95%CI: 0.79-1.11; GG vs AA: OR=0.88, 95%CI: 0.70-1.10; GG+AG vs AA: OR=0.92, 95%CI: 0.79-1.08; GG vs AA+AG: OR=0.91, 95%CI: 0.75-1.11). Conclusion: The findings suggest that pre-miR-218 rs11134527 polymorphism may have some relation to cancer development in Chinese. However, well-designed studies with larger sample size and more detailed data are needed to confirm these conclusions.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.16
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• pp.6855-6861
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• 2014

Background: Previous epidemiological studies have suggested a potential role of the $HSPA1B{\pm}1267A/G$ polymorphism in risk of developing cancer. However, the results were inconsistent. Therefore, we performed this meta-analysis to summarize the possible association with cancer risk. Materials and Methods: We retrieved relevant articles from PubMed, EMBASE, ISI Web of Science, Chinese Biomedical Literature and Chinese National Knowledge Infrastructure. Studies were selected using specific criteria. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess those associations. All analyses were performed using STATA software. Results: Fourteen case-control studies, including 1, 834 cancer cases and 2, 028 controls were included in this meta-analysis. Overall, the results indicated that the G allele of HSPA1B gene ${\pm}1267A/G$ was significantly associated with an increased cancer risk in all genetic models (G vs A: OR=1.51, 95%CI 1.17-1.95, p=0.001; GG vs AA: OR=2.93, 95%CI 1.50-5.74, p=0.002; AG vs AA: OR=1.48, 95%CI 1.10-1.98, p=0.009; GG/AG vs AA: OR=1.69, 95%CI 1.22-2.33, p=0.001; GG vs AG/AA: OR=2.31, 95%CI 1.24-4.32, p=0.009). In the subgroup analysis stratified by ethnicity, a significant association was identified in Caucasians (G vs A: OR=1.35, 95%CI 1.08-1.69, p=0.008; GG/AG vs AA: OR=1.36, 95%CI 1.09-1.70, p=0.007), but not in Asians. In the stratified analysis by cancer types, individuals with the G allele showed an increased risk of hepatocellular carcinoma compared with carriers of the A allele (OR=2.40, 95%CI 1.47-3.91, p<0.001). Inversely, individuals with the GG genotype showed a decreased risk of gastric cancer compared with carriers of the AG/GG genotypes (GG vs AG/AA: OR=0.39, 95%CI 0.20-0.70, p=0.007). Conclusions: This meta-analysis suggests associations between the HSPA1B ${\pm}1267A/G$ polymorphism and risk of cancer. However, this association might be Caucasian-specific and the G allele of this polymorphism probably increases risk of hepatocellular carcinoma while decreasing risk of gastric cancer. Further well-designed studies based on larger sample sizes are needed to validate these findings.

• Archives of Pharmacal Research
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• v.21 no.5
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• pp.521-526
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• 1998

The physicochmical properties of recombinant hepatitis B surface antigen (r-HBsAg), which was expressed in C127 mammalian cell were studied. Using roller bottle culture in DMEM supplemented with fetal bovine serum, 10-15 mg/L of r-HBsAg was produced with about 31% of purification yield. The purity of r-HBsAg by HPLC was 99.8% and electron microscopic examination showed homogeneous spherical particle with 22 nm in diameter, a morphological characteristic of HBsAg. The density of r-HBsAg by CsCI density gradient method was 1.19g/ml and the isoelectric point by Mono $P^{TM}$ HR 5/20 column was 4.6. The analysis of subunit protein pattern using SDS-PAGE followed by scanning densitometry gave 81.3% of S protein and 18.7% of pre-S protein. fluorophore-assisted-carbohydrate-electrophoresis analysis showed the relative amount of carbohydrate to protein was 1.7% and it smajr component was N-acetyl glucosamine, which was about 39% of total carbohydrate. The relative amount of lipid to protein determined by vanillin phosphoric acid method was 32.5% and its major component was phospholipid, which was about 70% of total lipid. The physicochemical properties of C127 mammalian cell-derved r-HBsAg are similar to those of p-HBsAg, suggesting that the r-HBsAg can be used in developing a new preventive vaccine against hepatitis B.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.7
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• pp.3273-3278
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• 2014

Background: Various studies have evaluated the relationship between X-ray repair cross-complementing group 1 (XRCC1) Arg399Gln polymorphism and hepatocellular carcinoma (HCC) risk, but the conclusions have been inconsistent and underpowered. The purpose of this updated meta-analysis was to examine whether XRCC1 Arg399Gln polymorphism confers susceptibility to HCC. Methods: Eligible studies extracted from PubMed, Embase, Cochrane Library, VIP (chinese) and CNKI (chinese) up to November 2013 were included in the study. Pooled odds ratio (OR) together with their 95% confidence interval (CI) were estimated to evaluate XRCC1 Arg399Gln polymorphism and HCC risk. Results: Finally, 21 studies with 4,170 cases and 5,030 controls were involved in our meta-analysis. The results demonstrated that there was significant association between Arg399Gln polymorphism and HCC risk under two contrast models in overall populations (AG vs GG: OR=1.265, 95%CI=1.036-1.545, p=0.021; AA+AG vs GG: OR=1.240, 95%CI=1.021-1.506, p=0.030). In subgroup analyses, significant association was found in Asians (A vs G: OR=1.175, 95%CI=1.013-1.362, p=0.033; AG vs GG: OR=1.317, 95%CI=1.070-1.622, p=0.009; AA+AG vs GG: OR=1.289, 95%CI=1.055-1.575, p=0.013) and Caucasians (A vs G: OR=0.591, 95%CI=0.361-0.966, p=0.036; AA+AG vs GG: OR=0.468, 95%CI=0.234-0.934, p=0.031). Conclusions: The results suggest that XRCC1 Arg399Gln polymorphism may increase HCC risk especially among Asians. However, XRCC1 Arg399Gln polymorphism might act as a protective role against HCC among Caucasians.