Removal of bacterial pathogen from wastewater using Al filter with Ag-containing nanocomposite film by in situ dispersion involving polyol process.

In this study, a filter with deposited Ag/Al(OH)(3) mesoporous nanocomposite film was fabricated to remove bacterial pathogens from wastewater. Mesoporous Al(OH)(3) film was generated on the Al foam body by alkali surface modification, followed by immersion in a polyol solution for 4h at an elevated temperature in order to deposit silver nanoparticles (Ag NPs). The Al(OH)(3) porous matrix showed a significant increase in specific surface area due to the large size of the voids between flakes, which reached several tens of nanometers. After in situ three-dimensional deposition of Ag NPs by a polyol process, the Ag NPs were nucleated and grown at the surface of the mesoporous Al(OH)(3) film. The filter with Ag/Al(OH)(3) mesoporous nanocomposite film showed a good bacterial pathogen removal rate within a very short contact time compared to the untreated Al foam filter. Filters with deposited Ag/Al(OH)(3) mesoporous nanocomposite film have great potential for application as antimicrobial filters for tap water purification, wastewater treatment, and other bio-related applications.

Prevalence of hepatitis C virus infections and distribution of hepatitis C virus genotypes among Korean blood donors.

BACKGROUND: Hepatitis C virus (HCV) remains a worldwide health-care burden. Prevalence rates vary and the distribution of genotypes depends on geographical location. Here, the recent prevalence of HCV infections and distribution of HCV genotypes among Korean blood donors were studied. METHODS: Between February 2005 and December 2009, a total of 11,064,532 donors were screened for anti-HCV and 11,412,690 donors were screened for HCV RNA. HCV genotyping was conducted for 748 blood donors with HCV RNA by using the line probe assay (VERSANT HCV Genotype 2.0 Assay, Bayer Healthcare, USA) after amplification of the 5'-untranslated and core regions of the genome. RESULTS: The anti-HCV prevalence was 0.16% (17,250/11,064,532). HCV RNA was detected in 959 out of the 11,412,690 donors (8.4/100,000). HCV RNA was more prevalent among women, donors who resided at harbor sites, and first-time donors. In addition, the prevalence of HCV RNA increased with age. The genotypes of 740 out of the 748 tested donors (98.9%) were identified. HCV genotype 1b (47.7%) and 2a/2c (35.0%) were dominant. Genotypes 2 (7.6%), 2b (2.3%), 3a (1.6%), 1a (1.3%), 1 (0.9%), 2v (0.5%), 1v (0.1%), and 3 (0.1%) were also identified. Genotype 4a/4c/4d (0.1%) was detected for the first time in one Korean blood donor. CONCLUSIONS: The distribution of HCV genotypes in Korea has not changed remarkably, with the exception of genotype 4a/4c/4d. A periodic study to monitor the prevalence of HCV infections and the distribution of HCV genotypes is required to identify emerging genotypes in Korea.

Ag/Al(OH)3 mesoporous nanocomposite film as antibacterial agent.

In this study, Ag/Al(OH)(3) mesoporous nanocomposite film was fabricated for antibacterial agent. As a matrix, a mesoporous Al(OH)(3) layer was prepared by alkali surface modification of an Al substrate. Subsequently, mesoporous Al(OH)(3) matrix was immersed in a polyol solution for 4h at an elevated temperature to deposit silver nanoparticles (Ag NPs) by in situ dispersion. The Al(OH)(3) porous matrix had flaky crystals weaved and covered all substrate surface so that the specific surface area was considerably increased because of voids having several tens of nanometers between the flakes. After in situ dispersion of Ag NPs by polyol process, the Ag NPs were nucleated and grown at the surface of mesoporous Al(OH)(3) layer with tight binding. In antibacterial activity, Ag/Al(OH)(3) mesoporous nanocomposite film demonstrated an excellent bacterial growth inhibition property. It is believed that the Ag/Al(OH)(3) mesoporous nanocomposite film is suitable for the antibacterial agent in a wide variety of biomedical applications.

Phosphate filtering characteristics of a hybridized porous Al alloy prepared by surface modification.

In this study, a porous Al alloy filter was designed for water purification systems. The combination of higher permeability for fluid flow and excellent filtering characteristics for removing pollutants is required for water purification. The filter's macropore structure was controlled by a powder metallurgical process using granulated powders for high permeability and its micropore structure was generated by alkali surface modification on the macroporous sintered body for enhanced filtration efficiency. After surface modification, the specific surface area was increased by 10 times over the as-sintered specimen. Phosphate filtering characteristic was noticeably improved by a ligand exchange between phosphate and aluminum hydroxide formed by alkali surface modification.

[Utility of D-dimer assay for diagnosing pulmonary embolism: single institute study].

BACKGROUND: Pulmonary embolism (PE) presents with diverse non-specific signs and symptoms and its diagnosis mainly depends on diagnostic imaging tests which are laborious and not cost-effective, and only a small proportion of patients with suspected PE actually have the disease. The aim of this study was to analyze the utility of D-dimer test for diagnosing PE by categorizing patients into 'PE likely' and 'PE unlikely' groups using Wells score for clinical probability. METHODS: One hundred forty consecutive patients with clinically suspected PE, in whom D-dimer and imaging tests were performed were enrolled. Dignosis of PE was made when the imaging tests were positive. Wells scores were retrospectively assigned and the dignostic utility of D-dimer test was analyzed. RESULTS: Of the 140 patients studied, D-dimer test was positive in 97 and diagnostic imaging tests revealed PE, deep vein thrombosis (DVT), and PE+DVT in 24, 3, and 7 patients, respectively. For the diagnosis of PE, D-dimer test with cutoff value of > or =230 ng/mL showed sensitivity, specificity, and negative predictive value of 96.8%, 39.6%, and 97.7%, respectively. These values were 96.3%, 37.9%, and 91.7% in 'PE likely' group (n=56), and 100%, 38.8%, and 100% in 'PE unlikely' group (n=84). Among 43 patients with D-dimer values of <230 ng/mL, only one patient was diagnosed with PE, who belonged to the 'PE likely' group. CONCLUSIONS: D-dimer test cannot be used as a stand-alone test to diagnose PE, but it can be helpful for exclusion of PE especially in 'PE unlikely' group according to Wells score.

[A case of therapy-related acute monocytic leukemia following low-dose of etoposide treatment for hemophagocytic lymphohistiocytosis].

We report a case of therapy-related acute myeloid leukemia after low-dosed topoisomerase II inhibitor (etoposide) treatment for hemophagocytic lymphohistiocytosis (HLH). A 62-yr-old female patient had previously been treated with a HLH-94 protocol containing a low-dose of etoposide (total dose of 300 mg/m2). Thirty-one months later, the patient was admitted to the hematology department with general weakness and upper respiratory infection symptoms. Peripheral blood smear and bone marrow study revealed acute monocytic leukemia. There was no evidence of myelodysplastic syndrome, and a cytogenetic study showed no chromosomal abnormalities.