Risk factors for hospital-acquired infection during the SARS-CoV-2 pandemic

OBJECTIVE

To evaluate risk factors for hospital-acquired infection (HAI) in patients during the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic, including historical and concurrent cohorts.

DESIGN

Retrospective cohort.

SETTING

Three Missouri hospitals, data from 1^st January 2017 to 30^th September 2020.

PARTICIPANTS

Patients aged ≥18 years and admitted for ≥48 h.

METHODS

Univariate and multi-variate Cox proportional hazards models incorporating the competing risk of death were used to determine risk factors for HAI. A-priori sensitivity analyses were performed to assess the robustness of the urine-, blood- and respiratory-culture-based HAI definition.

RESULTS

The cohort included 254,792 admissions, with 7147 (2.8%) HAIs (1661 blood, 3407 urine, 2626 respiratory). Patients with SARS-CoV-2 had increased risk of HAI (adjusted hazards ratio 1.65, 95% confidence interval 1.38-1.96), and SARS-CoV-2 infection was one of the strongest risk factors for development of HAI. Other risk factors for HAI included certain admitting services, chronic comorbidities, intensive care unit stay during index admission, extremes of body mass index, hospital, and selected medications. Factors associated with lower risk of HAI included year of admission (declined over the course of the study), admitting service and medications. Risk factors for HAI were similar in sensitivity analyses restricted to patients with diagnostic codes for pneumonia/upper respiratory infection and urinary tract infection.

CONCLUSIONS

SARS-CoV-2 was associated with significantly increased risk of HAI.

Viral antigen nanoparticles for discriminated and quantitative detection of different subtypes of anti-virus immunoglobulins

The aim of this study is to develop a novel method for the accurate diagnosis of the infection status of viral diseases, which requires discriminated and quantitative detection of different anti-virus immunoglubulin subtypes. Considering hepatitis A as a representative model disease, viral antigen nanoparticles (vAgNPs) were designed and synthesized by genetically presenting hepatitis A virus (HAV) antigens on the surface of human heavy chain ferritin (hFTH) nanoparticles to detect anti-HAV antibodies with discriminating immunoglobulin subtypes M and G (IgM and IgG, respectively). The vAgNPs also display multi-copies of hexa-histidine peptide (H6) on their surface to chemisorb gold ions (Au3+), which is vital for the autonomous generation of quantitatively meaningful detection signals. The quantitative level of anti-HAV IgM or IgG in 30 patient sera was successfully analyzed using the vAgNPs of HAV, which was performed through label-free one-step-immunoassay based on the self-enhancement of optical signals from gold nanoparticles clustered on the viral antigen nanoparticles. The diagnostic performance was compared with that of enzyme-linked immunosorbent assay (ELISA), which did not enable accurate quantitative assay due to the poor linearity between the antibody concentration and detection signal. Furthermore, these vAgNP-based immunoassays did not produce any false negative/positive signals, indicating 100% sensitivity and 100% specificity.

Association between time to treatment and functional outcomes according to the Diffusion-Weighted Imaging Alberta Stroke Program Early Computed Tomography Score in endovascular stroke therapy

BACKGROUND AND PURPOSE

The rate at which the chance of a good outcome of endovascular stroke therapy (EVT) decays with time when eligible patients are selected by baseline diffusion-weighted magnetic resonance imaging (DWI-MRI) and whether ischaemic core size affects this rate remain to be investigated.

METHODS

This study analyses a prospective multicentre registry of stroke patients treated with EVT based on pretreatment DWI-MRI that was categorized into three groups: small [Diffusion-Weighted Imaging Alberta Stroke Program Early Computed Tomography Score (DWI-ASPECTS)] (8-10), moderate (5-7) and large (<5) cores. The main outcome was a good outcome at 90 days (modified Rankin Scale 0-2). The interaction between onset-to-groin puncture time (OTP) and DWI-ASPECTS categories regarding functional outcomes was investigated.

RESULTS

Ultimately, 985 patients (age 69 ± 11 years; male 55%) were analysed. Potential interaction effects between the DWI-ASPECTS categories and OTP on a good outcome at 90 days were observed (P_interaction  = 0.06). Every 60-min delay in OTP was associated with a 16% reduced likelihood of a good outcome at 90 days amongst patients with large cores, although no associations were observed amongst patients with small to moderate cores. Interestingly, the adjusted rates of a good outcome at 90 days steeply declined between 65 and 213 min of OTP and then remained smooth throughout 24 h of OTP (P_nonlinearity  = 0.15).

CONCLUSIONS

Our study showed that the probability of a good outcome after EVT nonlinearly decreased, with a steeper decline at earlier OTP than at later OTP. Discrepant effects of OTP on functional outcomes by baseline DWI-ASPECTS categories were observed. Thus, different strategies for EVT based on time and ischaemic core size are warranted.

Performance of point-of-care diagnosis of AIDS: label-free one-step-immunoassay vs. lateral flow assay

The objective of this study is to develop an accurate, rapid, simple, and label-free assay technology that enables point-of-care diagnosis of AIDS. For this, 3-dimensional (3D) probes to sensitively detect anti-HIV antibodies were designed and synthesized by genetically presenting a HIV antigen (gp41) on the surface of engineered human ferritin nanoparticles. The 3D probes also present multi-copies of the hexa-histidine peptide (H₆) on their surface to chemisorb gold ions (Au³⁺), which is essential for the generation and self-enhancement of assay signals. The developed new assay technology (named "one-step-immunoassay") quickly produced clear optical signals through a simple and convenient one-step procedure. The diagnostic performance of the one-step-immunoassay was compared with that of the conventional lateral flow assay (LFA) using 30 AIDS patient and 20 healthy sera. The sensitivity of LFA was only 63% when a single antigen (gp41) was used but enhanced to 90% when three different antigens (gp41, p24, and gp120) were used together as the assay probes. In contrast, the one-step-immunoassay using only gp41 produced strong optical signals within 15 min without causing any false negative/positive signals, showing 100% sensitivity and 100% specificity and holding promising potential for clinical point-of-care diagnosis of AIDS.

Early development of de novo hepatocellular carcinoma after direct-acting agent therapy: Comparison with pegylated interferon-based therapy in chronic hepatitis C patients

Patients with chronic hepatitis C who achieve a sustained viral response after pegylated interferon therapy have a reduced risk of hepatocellular carcinoma, but the risk after treatment with direct-acting antivirals is unclear. We compared the rates of early development of hepatocellular carcinoma after direct-acting antivirals and after pegylated interferon therapy. We retrospectively analysed 785 patients with chronic hepatitis C who had no history of hepatocellular carcinoma (211 treated with pegylated interferon, 574 with direct-acting antivirals) and were followed up for at least 24 weeks after antiviral treatment. De novo hepatocellular carcinoma developed in 6 of 574 patients receiving direct-acting antivirals and in 1 of 211 patients receiving pegylated interferon. The cumulative incidence of early hepatocellular carcinoma development did not differ between the treatment groups either for the whole cohort (1.05% vs 0.47%, P = .298) or for those patients with Child-Pugh Class A cirrhosis (3.73% vs 2.94%, P = .827). Multivariate analysis indicated that alpha-fetoprotein level >9.5 ng/mL at the time of end-of-treatment response was the only independent risk factor for early development of hepatocellular carcinoma in all patients (P < .0001, hazard ratio 176.174, 95% confidence interval 10.768-2882.473) and in patients treated with direct-acting agents (P < .0001, hazard ratio 128.402, 95% confidence interval 8.417-1958.680). In conclusion, the rate of early development of hepatocellular carcinoma did not differ between patients treated with pegylated interferon and those treated with direct-acting antivirals and was associated with the serum alpha-fetoprotein level at the time of end-of-treatment response.

Experimental infection of H5N1 and H5N8 highly pathogenic avian influenza viruses in Northern Pintail (Anas acuta)

The wide geographic spread of Eurasian Goose/Guangdong lineage highly pathogenic avian influenza (HPAI) clade 2.3.4.4 viruses by wild birds is of great concern. In December 2014, an H5N8 HPAI clade 2.3.4.4 Group A (2.3.4.4A) virus was introduced to North America. Long-distance migratory wild aquatic birds between East Asia and North America, such as Northern Pintail (Anas acuta), were strongly suspected of being a source of intercontinental transmission. In this study, we evaluated the pathogenicity, infectivity and transmissibility of an H5N8 HPAI clade 2.3.4.4A virus in Northern Pintails and compared the results to that of an H5N1 HPAI clade 2.3.2.1 virus. All of Northern Pintails infected with either H5N1 or H5N8 virus lacked clinical signs and mortality, but the H5N8 clade 2.3.4.4 virus was more efficient at replicating within and transmitting between Northern Pintails than the H5N1 clade 2.3.2.1 virus. The H5N8-infected birds shed high titre of viruses from oropharynx and cloaca, which in the field supported virus transmission and spread. This study highlights the role of wild waterfowl in the intercontinental spread of some HPAI viruses. Migratory aquatic birds should be carefully monitored for the early detection of H5 clade 2.3.4.4 and other HPAI viruses.

Limited pathogenicity and transmissibility of Korean highly pathogenic avian influenza H5N6 clade 2.3.4.4 in ferrets

The pathogenicity and transmissibility of a reassortant clade 2.3.4.4 avian influenza A (H5N6) virus were evaluated in ferrets. Virus excretion was detected in the upper respiratory tract, but the ferrets did not show any clinical signs of infection. Transmission did not occur between cohoused or respiratory droplet-contact ferrets.

Current-induced magnetic switching with spin-orbit torque in an interlayer-coupled junction with a Ta spacer layer

Spin-orbit torque has attracted considerable attention as a means to overcome limits of devices based on spin-transfer torque. However, a small magnetic field that is collinear to the current flow must be applied to break symmetry and induce deterministic current-induced magnetization switching. Recently, a junction utilizing interlayer coupling mediated by a Ru spacer layer between two CoFe layers was designed for symmetry breaking and exhibited current-induced magnetization switching without a magnetic field. Here, we demonstrate zero-field current-induced switching of the perpendicular magnetization of a Co layer that is indirectly coupled with a CoFe layer via a Ta spacer. The weak interlayer coupling exhibited by Ta allows the layer thickness to be relatively small (≈0.5 nm), enabling appropriate interlayer coupling to induce spin-orbit torque for current-induced magnetic switching. External magnetic field effects on switching characteristics show that the current switching process is quite stable against external environments.

Dual-graft adult living donor liver transplantation with ABO-incompatible graft: short-term and long-term outcomes

ABO-incompatible (ABOi) dual-graft (DG) adult living donor liver transplantation (ALDLT) is not commonly performed due to its inherently intricate surgical technique and immunological complexity. Therefore, data are lacking on the short- and long-term clinical outcomes of ABOi DG ALDLT. We performed a retrospective study by reviewing the medical records of patients who underwent ABOi DG ALDLT between 2008 and 2014. Additionally, computed tomography volumetric analysis was conducted to assess the graft regeneration rate. The mean age of a total of 28 recipients was 50.2 ± 8.5 years, and the mean model for end-stage liver disease score was 12.2 ± 4.6. The 1-, 3-, and 5-year patient survival rate was 96.4% during the mean follow-up period of 57.0 ± 22.4 months. The 1-, 3-, and 5-year graft survival rate was 96.4%, 94.2%, and 92.0%, respectively, and no significant differences were observed between ABO-compatible (ABOc) and ABOi grafts (P = .145). The biliary complication rate showed no significant difference (P = .195) between ABOc and ABOi grafts. Regeneration rates of ABOi grafts were not significantly different from those of ABOc grafts. DG ALDLT with ABOi and ABOc graft combination seems to be a feasible option for expanding the donor pool without additional donor risks.

Signal self-enhancement by coordinated assembly of gold nanoparticles enables accurate one-step-immunoassays

Current immunoassays are in general performed through time-consuming multi-step procedures that depend on the use of premade signal-producing reporters and often cause assay inaccuracy. Here we report an advanced immunoassay technology that resolves the delayed, complex, and inaccurate assay problems of conventional immunoassays. We have developed an accurate, rapid, simple, and label-free one-step-immunoassay based on the self-enhancement of sensitive immunoassay signals in an assay solution. The nano-scale protein particles (hepatitis B virus capsid and human ferritin heavy chain particles) were genetically engineered to present many well-oriented antibody (or antigen) probes and multi-copies of poly-histidine peptides on their surface, resulting in the construction of 3-dimensional (3D) bioprobes that chemisorb gold ions via coordination bonding and sensitively detect both antigen and antibody analytes. Systematic numerical and experimental analyses show that the signal self-enhancement happens through two coupled reactions under reducing conditions: (1) 3D bioprobe-based sensitive immuno-detection of analytes and (2) coordinated assembly of free and chemisorbed gold nanoparticles around the 3D bioprobe-analyte-associated complexes, which is followed by the quick generation of apparent optical signals. This advanced one-step-immunoassay was successfully applied to diagnostic assays requiring high accuracy and/or speed, i.e. diagnosis of acute myocardial infarction and hepatitis C through detecting a cardiac protein (troponin I) and anti-hepatitis C virus antibodies in patient sera, indicating that it is applicable to the accurate and rapid detection of both antigen and antibody markers of a wide range of diseases.

Living Donor Liver Transplantation for Patients Older Than Age 70 Years: A Single-Center Experience

Over the past two decades, the age of liver transplantation (LT) recipients has been increasing. We reviewed our experience with LT for patients aged ≥70 years (range: 70-78 years) and investigated the feasibility of performing LT, especially living donor LT (LDLT), for older patients. We retrospectively reviewed the medical records of 25 patients (15 LDLT recipients, 10 deceased donor LT recipients) aged ≥70 years who underwent LT from January 2000 to April 2016. Their perioperative morbidity rate was 28.0%, and the in-hospital mortality rate was 16.0%; these results were comparable to those of matched patients in their 60s (n = 73; morbidity, p = 0.726; mortality, p = 0.816). For patients in their 70s, the 1- and 5-year patient survival rates were 84.0% and 69.8%, and the 1- and 5-year graft survival rates were 83.5% and 75.1%, respectively. Comparisons of patient and graft survival rates between matched patients in their 60s and 70s showed no statistically significant differences (patient survival, p = 0.372; graft survival, p = 0.183). Our experience suggests that patients aged ≥70 years should not be excluded from LT, or even LDLT, based solely on age and implies that careful selection of recipients and donors as well as meticulous surgical technique are necessary for successful results.

First Report of Alternaria Leaf Spot Caused by Alternaria sp. on Highbush Blueberry (Vaccinium corymbosum) in South Korea

In South Korea, the culture, production, and consumption of blueberry (Vaccinium corymbosum) have increased rapidly over the past 10 years. In June and July 2012, blueberry plants with leaf spots (~10% of disease incidence) were sampled from a blueberry orchard in Jinju, South Korea. Leaf symptoms included small (1 to 5 mm in diameter) brown spots that were circular to irregular in shape. The spots expanded and fused into irregularly shaped, large lesions with distinct dark, brownish-red borders. The leaves with severe infection dropped early. A fungus was recovered consistently from sections of surface-disinfested (1% NaOCl) symptomatic leaf tissue after transfer onto water agar and sub-culture on PDA at 25°C. Fungal colonies were dark olive and produced loose, aerial hyphae on the culture surfaces. Conidia, which had 3 to 6 transverse septa, 1 to 2 longitudinal septa, and sometimes also a few oblique septa, were pale brown to golden brown, ellipsoid to ovoid, obclavate to obpyriform, and 16 to 42 × 7 to 16 μm (n = 50). Conidiophores were pale to mid-brown, solitary or fasciculate, and 28 to 116 × 3 to 5 μm (n = 50). The species was placed in the Alternaria alternata group (1). To confirm the identity of the fungus, the complete internal transcribed spacer (ITS) rDNA region of a representative isolate, AAVC-01, was amplified using ITS1 and ITS4 primers (2). The DNA products were cloned into the pGEM-T Easy vector (Promega, Madison, WI) and the resulting pOR13 plasmid was sequenced using universal primers. The resulting 570-bp sequence was deposited in GenBank (Accession No. KJ636460). Comparison of ITS rDNA sequences with other Alternaria spp. using ClustalX showed ≥99% similarity with the sequences of A. alternata causing blight on Jatropha curcas (JQ660842) from Mexico and Cajannus cajan (JQ074093) from India, citrus black rot (AF404664) from South Africa, and other Alternaria species, including A. tenuissima (WAC13639) (3), A. lini (Y17071), and A. longipes (AF267137). Two base substitutions, C to T at positions 345 and 426, were found in the 570-bp amplicon. Phylogenetic analysis revealed that the present Alternaria sp. infecting blueberry grouped separately from A. tenuissima and A. alternata reported from other hosts. A representative isolate of the pathogen was used to inoculate V. corymbosum Northland leaves for pathogenicity testing. A conidial suspension (2 × 10⁴ conidia/ml) from a single spore culture and 0.025% Tween was spot inoculated onto 30 leaves, ranging from recently emerged to oldest, of 2-year-old V. corymbosum Northland plants. Ten leaves were treated with sterilized distilled water and 0.025% Tween as a control. The plants were kept in a moist chamber with >90% relative humidity at 25°C for 48 h and then moved to a greenhouse. After 15 days, leaf spot symptoms similar to those observed in the field developed on the inoculated leaves, whereas the control plants remained asymptomatic. The causal fungus was re-isolated from the lesions of the inoculated plants to fulfill Koch's postulates. To our knowledge, this is the first report of Alternaria sp. on V. corymbosum in South Korea. References: (1) E. G. Simmons. Page 1797 in: Alternaria: An Identification Manual. CBS Fungal Biodiversity Centre, Utrecht, The Netherlands, 2007. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990. (3) M. P. You et al. Plant Dis. 98:423, 2014.

First Report of Sclerotium Rot Caused by Sclerotium rolfsii on Yacón in South Korea

Yacón, or ground apple (Smallanthus sonchifolius), is a perennial plant grown in the northern and central Andes from Colombia to northern Argentina for its crisp, sweet, and tuberous roots. In 2012, yacóns cultivated in the research field of the Gyeongsangnam-do Agriculture and Extension Services, Jinju, South Korea, suddenly died. The characteristic symptoms consisted of rotting, wilting, and blighting. Initial symptoms included water-soaked lesions on lower stem tissue near the soil line. Infected plants gradually withered, and white mycelial mats and sclerotia appeared on the surface of roots and stems at the soil line. The sclerotia were collected and disinfested by immersion in 1% sodium hypochlorite solution for 30 s and in sterilized distilled water for 1 min. Then, the sclerotia were placed on potato dextrose agar (PDA) and incubated at 30°C. Numerous globoid sclerotia were formed on PDA after 18 days of growth. The sclerotia (1 to 3 mm in diameter) were white at first and then gradually turned dark brown. Aerial mycelia usually formed many narrow hyphal strands 4 to 9 μm wide. The white mycelium formed a typical clamp connection after 5 days of growth. To fulfill Koch's postulates, 50-day-old healthy seedlings were transplanted individually into pots (10 × 10 × 9 cm) containing autoclaved soil. After 7 days, five seedlings were inoculated with colonized agar discs (6 mm in diameter) directly on the base of the plant, and five yacón seedlings were inoculated similarly with PDA discs as the control treatment. The inoculated and non-inoculated plants were incubated in a humid growth chamber at 28°C for 24 h and then maintained in a greenhouse. Eight days after inoculation, the yacón seedlings inoculated with the fungus died, whereas those treated with PDA discs were symptomless. The fungus was re-isolated from the artificially inoculated plants. To confirm the identity of the causal fungus, the complete internal transcribed spacer (ITS) rDNA region of the fungus was amplified using the primers ITS1 (5'-TCCGTAGGTGAACCTGCGG-3') and ITS4 (5'-TCCTCCGCTTATTGATATGC-3') (2), and the PCR amplicons were cloned into the pGEM-T Easy vector. The resulting plasmid (pOR119) was sequenced in both directions with the primers M13F and M13R. The resulting 684 bp of ITS rDNA sequence was deposited in GenBank (Accession No. KJ944395). A DNA analysis revealed that it was 100% identical to Sclerotium rolfsii (HM355751). Cultures of S. rolfsii have been deposited with the Korean Agricultural Culture Collection (KACC 47750), National Academy of Agricultural Science, Suwon, South Korea. On the basis of symptoms, fungal colonies, the ITS sequence, and pathogenicity to the host, this fungus was identified as S. rolfsii Saccardo (1). This is the first report of sclerotium rot on yacón caused by S. rolfsii in South Korea. References: (1) J. E. M. Mordue. CMI Descriptions of Pathogenic Fungi and Bacteria, No. 410, 1974. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.

Anti-adhesive effect of a thermosensitive poloxamer applied after the removal of nasal packing in endoscopic sinus surgery: a randomised multicentre clinical trial

OBJECTIVE

To compare the efficacies of a thermosensitive poloxamer (TPX) and Merogel in preventing adhesion applied after the removal of nasal packing in endoscopic sinus surgery as a non-inferiority trial.

DESIGN

Randomised, multicentre, single-blind, active-controlled, matched-pair study.

SETTING

Yonsei University Gangnam Severance Hospital, Korea University Guro Hospital.

PARTICIPANTS

A total of 70 patients were enroled and underwent endoscopic sinus surgeries. Four of the patients did not complete their follow-up. Analysis of the 66 enroled patients having completed postoperative assessment was performed. The severity of rhinosinusitis was graded with a Lund-McKay CT score, and only those with bilateral disease and a CT score difference ≤2 between sinuses were included.

MAIN OUTCOME MEASURES

An independent rhinologist from a third institution through a blinded assessment with digital photoendoscopy of the middle meati bilaterally taken postoperatively.

RESULTS

In the blinded assessment, thermosensitive poloxamer (anti-adhesion rate: 92%) was similar to Merogel (anti-adhesion rate: 89%). Evaluation of the presence and grade of adhesion, oedema, and infection in the middle meatus revealed no significant differences between the thermosensitive poloxamer group and the Merogel group at all postoperative periods.

CONCLUSION

Anti-adhesive effects of thermosensitive poloxamer are similar to those of Merogel. Therefore, thermosensitive poloxamer can be considered a safe alternative to Merogel for preventing adhesion in patients undergoing endoscopic sinus surgeries, and further evaluation of thermosensitive poloxamer as an anti-adhesive and primary packing material compared with the control using no packing is needed.

Fusarium oxysporum Causing Wilt and Stem Rot in Chrysanthemum × morifolium in Korea

The hardy garden mum Chrysanthemum, or "mum" (Chrysanthemum × morifolium Ram.), is a popular flowering herbaceous perennial that is commonly grown for fall sales. In October 2011, suspected wilt disease was observed in potted hardy garden mums (cv. Guiin) grown in greenhouses in Jinju, South Korea. Symptoms included unilateral chlorosis of leaves at the stem apex. Wilted leaves occurred initially on the most severely affected side of the plant, but as the disease progressed, the entire plant wilted and died. Black necrosis and vascular discoloration at the base of stems always developed. Five fungal isolates, successfully isolated from 10 infected stems on potato dextrose agar (PDA), yielded rapidly growing floccose to felt-like colonies, initially white, but turning peach colored. The microconidia were ellipsoid, ovoid, and cylindrical, and measured 3 to 12 × 1 to 3 μm. The macroconidia were falcate, lunate, and measured 8 to 30 × 2 to 4 μm, and had 1 to 5 septa. Pathogenicity was studied in inoculated, potted plants in a greenhouse. A representative isolate of the fungus was grown on PDA at 20°C for about 10 days before inoculation. To obtain conidial suspensions, 10 ml of sterile distilled water (SDW) was added to the culture plates and scraped with a paintbrush to dislodge conidia. The suspension from the culture plates was filtered through cheesecloth and diluted to 2 × 10⁴ micro- and macroconidia/ml with SDW. Nine 3-month-old hardy garden mums were planted in 20-cm-diameter plastic pots containing fine sand. After 10 days, the roots were cut to a depth of 5 cm on two sides of each plant at a distance of 2 cm from the stems. Then, 10 ml of conidial suspension were poured into each pot above the cuts roots, followed by 20 ml 12 days later. Three mums treated with SDW served as controls. Plants were fertilized twice weekly with 100 ml/pot of a nutrient solution (1) that lowered the soil pH and enhanced wilt development. Thirty days after inoculation, all of the artificially inoculated plants had wilted. The control mums remained healthy. The fungus was successfully reisolated to complete Koch's postulates. On the basis of the morphological characters, the fungus was identified as Fusarium oxysporum (3). To identify the isolated fungus, the complete internal transcribe spacer (ITS) rDNA and translation elongation factor 1-alpha (EF1-α) sequences were amplified using the primers ITS1/ITS4 and EF1/EF2, respectively, and sequenced. The resulting sequences were deposited in GenBank (Accession Nos. KC491873 and KC491875). A BLAST search of ITS rDNA (544 bp) and EF1-α (712 bp) sequences against a database of fungal isolates found 100% and 99% similarity to those of F. oxysporum, respectively. Fusarium wilt caused by F. oxysporim on C. morifolium has been previously recorded in North America and India but, to our knowledge, this is the first report of F. oxysporum causing wilt in hardy garden mum in Korea (2). F. oxysporum isolates causing wilts are specific to certain hosts and even to host varieties or cultivars. Further work is required to determine to which forma specialis and race the pathogen belongs. References: (1) A. W. Engelhard and S. S. Woltz. Proc. Fla. State Hort. Soc. 84:351, 1971. (2) H. C. Huang et al. Plant Pathol. Bull. 1:57, 1992. (3) C. V. Subramanian. CMI Descriptions of Pathogenic Fungi and Bacteria. No. 217, 1970.

Sclerotium rolfsii Causes White Rot on Taro in Korea

Taro (Colocasia esculenta L.) is grown throughout the world primarily for its tubers, which become edible after cooking. Taro stems are often used in a traditional soup in South Korea. In September 2012, a suspected white rot of taro occurred in a farmer's fields in Jinju, South Korea. Infected plants gradually withered, a white mycelial mat appeared, and numerous sclerotia developed on the surface of petioles near the soil line. The heavily infected petioles rotted and the entire plant eventually died. The freshly isolated pathogenic fungus was grown on potato dextrose agar (PDA) and examined microscopically. Aerial mycelia usually formed many narrow hyphal strands 4 to 8 μm wide. The white mycelia formed a typical clamp connection structure after 6 days growth at 25°C. The sclerotia were white at first, gradually turned dark brown, and were 1 to 3 mm in diameter. Small globoid sclerotia formed abundantly on PDA after 18 days of growth. Ten 2-month-old potted taro plants were inoculated with S. rolfsii-colonized agar discs directly at the base of each plant and kept at 25°C in a greenhouse to test pathogenicity. Three taro plants were inoculated similarly with uncolonized agar discs as controls. Eight days after inoculation, blight symptoms were observed, and S. rolfsii was reisolated from the artificially inoculated plants. The control taro plants remained healthy. We amplified and sequenced an internal transcribed spacer (ITS) rDNA region of the isolate using the ITS1 (5'-TCCGTAGGTGAACCTGCGG-3') and ITS4 (5'-TCCTCCGCTTATTGATATGC-3') primers to confirm the identity of the fungus (2). The resulting 684-bp sequence was deposited in GenBank (Accession No. KC491876). A comparison with other sequences available in the GenBank database revealed that the ITS sequence shared 100% similarity with Sclerotium rolfsii sequences (HQ420816 and JN017199). Based on the symptoms, mycological characteristics, ITS sequence analysis, and host plant pathogenicity, this fungus was identified as S. rolfsii Saccardo (1). To our knowledge, this is the first report of white rot in taro caused by S. rolfsii in Korea. References: (1) J. E. Mordue. CMI Descriptions of Pathogenic Fungi and Bacteria. No. 410, 1974. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, New York, 1990.

First Report of Anthracnose on Rohdea japonica Caused by Colletotrichum liriopes in Korea

Lily of China (Rohdea japonica Roth) is a flowering plant native to eastern Asia. In the summers of 2010 and 2011, suspected anthracnose disease was observed on R. japonica plants in the exhibition field of Jinju Agriculture Technology Center, Jinju, South Korea. Symptoms began as yellow to brown spots on leaves and darkened as the spots expanded. The lesions subsequently became dark brown, and bristled acervuli were observed on the dark brown areas. Leaf spots led to leaf shriveling and eventual death. Fresh leaf specimens were collected from infected plants and the putative causal pathogen was isolated on potato dextrose agar (PDA). The fungus formed a dark brown colony, irregularly shaped black sclerotia, and abundant setae in PDA cultures. Conidia were colorless, falcate, fusiform, and 21 to 26 × 2 to 3 μm. Appressoria were clavate to circular and 8 to 12 × 6 to 8 μm. Amplification of the internal transcribed spacer was conducted as described previously (2) and generated a 577-bp sequence (GenBank Accession No. JQ677042) with 99% identity to sequences of C. liriopes strain CBS 119444 (GU227804), identified previously as C. dematium from Agavaceae (1). In the phylogenetic tree, the representative strain was placed within a clade comprising a reference strain of C. liriopes (data not shown). A representative isolate of the pathogen was used to inoculate R. japonica leaves for pathogenicity testing. Five 4-month-old R. japonica plants were sprayed to runoff with a conidial suspension (10⁴ conidia/ml) and 0.025% Tween. Three plants were sprayed with sterilized distilled water and 0.025% Tween as a control. The plants were kept in a moist chamber with >90% relative humidity at 25°C for 48 h and then moved to a greenhouse. After 7 days of incubation, necrotic spot symptoms similar to those observed in the field developed on the inoculated leaves. Control plants remained asymptomatic. The pathogenicity test was repeated twice with similar results and the causal fungus was reisolated from the lesions of inoculated plants to satisfy Koch's postulates in each test. On the basis of observed symptoms, morphology, pathogenicity, and molecular characterization, this fungus was identified as Colletotrichum liriopes. The recent outbreak of leaf spot on R. japonica plants suggests that C. liriopes is spreading and poses a serious threat to these plants in Korea. References: (1) U. Damm et al. Fungal Diversity 39:45, 2009. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications, M. A. Innis et al., eds., Academic Press, Inc., New York, 1990.

An Outbreak of Leaf Spot Caused by Corynespora cassiicola on Korean Raspberry in Korea

In September and October 2010, leaf spots were observed on Korean raspberry (Rubus crataegifolius Bunge) plants in farmers' fields in Hapcheon, Gyeongnam Province, South Korea. Disease incidence ranged from 50 to 80% among fields. Circular- to irregular-shaped spots surrounded by yellow halos occurred frequently on the leaves of Korean raspberry plants. Brown spots became dark with wavy borders and ranged from 20 to 300 mm in diameter. Infected leaves became chlorotic, blighted, and eventually died. Fungal hyphae covered the lesions with abundant conidia and conidiophores. Fresh leaf specimens were collected from infected plants and the putative causal pathogen was isolated onto potato dextrose agar (PDA). A total of 30 isolates of the fungus were collected from diseased plants collected in the field. Fungal colonies were gray to brown on PDA. Colonies formed conidia, 38 to 210 × 8 to 20 μm, which were solitary or catenary, obclavate to cylindrical, smooth, straight or curved, and subhyaline to pale brown or brown. Conidiophores, 98 to 840 × 4 to 12 μm, were slightly or conspicuously swollen at apex, single, simple, straight or slightly flexuous, pale to midbrown, smooth, septate, thick, monotretic, and determinate or in tufts. Morphological characteristics of the fungal specimens were similar to descriptions of Corynespora cassiicola (1). A representative isolate of the pathogen was used to inoculate leaves of Korean raspberry plants for pathogenicity testing. Five leaves of a 3-month-old potted plant were sprayed with a suspension of conidia in water. Conidia were harvested from PDA cultures and adjusted to 2 × 10⁴ conidia/ml with a hemocytometer. Five leaves sprayed with sterile distilled water served as controls. Inoculated plants were placed in a humid chamber with 100% relative humidity at 30°C for 24 h and then moved to a greenhouse. Symptoms similar to those observed in the farmers' fields developed on the inoculated leaves within 12 days, whereas the controls remained asymptomatic. The causal fungus was reisolated from the lesions of inoculated plants to satisfy Koch's postulates. To confirm the identity of the fungus, the complete internal transcribed spacer (ITS) rDNA region was amplified and sequenced (3). Amplification of the ITS region generated a 559-bp sequence (GenBank Accession No. JQ340026) with 100% similarity to sequences of C. cassiicola in GenBank (Accession No. GU138988) causing leaf spot on cassava (2). Based on the symptoms, morphological characteristics, pathogenicity, and molecular identification, this fungus was identified as C. cassiicola (1). To our knowledge, this is the first report of leaf spot caused by C. cassiicola on Korean raspberry. The recent occurrence of leaf spot on Korean raspberry suggests that C. cassiicola is spreading widely and posing a serious threat to these plants in Korea. References: (1) M. B. Ellis et al. No. 303 in: CMI Descriptions of Pathogenic Fungi and Bacteria. Surrey, Kew, UK, 1971. (2) X.-B. Liu et al. Plant Dis. 94:916, 2010. (3) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, Inc., New York, 1990.

The embryo lethality of Escherichia coli isolates and its relationship to the presence of virulence-associated genes

The aims of this study were to determine if the chicken embryo lethality assay and the presence of 9 virulence-associated genes of Escherichia coli were correlated and to discover which virulence genes contributed most to embryo lethality. We examined 58 E. coli strains isolated from visceral organs of chickens with colibacillosis for the presence of 9 virulence genes (fimC, tsh, fyuA, irp2, iucD, cvi/cva, iss, astA, and vat) by PCR. The gene FimC (type I fimbriae) was detected with the highest prevalence in 93.1% of the isolates, followed by iucD (67.24%), iss (58.62%), tsh (34.48%), cvi/cva (34.48%), fyuA (32.76%), astA (31.0%), irp2 (27.59%), and vat (17.24%). The embryo mortality ranged from 5 to 100%; however, most of the isolates were moderately or highly virulent. High positive correlations were observed between the presence of virulence genes and chicken embryo lethality. In addition, presence of the iucD (aerobactin) gene was the trait that best contributed to embryo mortality by using the multivariate model. These results suggest that expression frequency of these 9 virulence genes is associated with embryo mortality, and the gene that best predicted embryo mortality was iucD.

Pretreatment HBeAg level and an early decrease in HBeAg level predict virologic response to entecavir treatment for HBeAg-positive chronic hepatitis B

There are few reports on hepatitis B e antigen (HBeAg) titres during nucleos(t)ide analogues treatment. We investigated the changes in HBeAg levels in patients treated with entecavir and the usefulness of HBeAg quantification for predicting antiviral response. Ninety-five consecutive HBeAg-positive patients treated with entecavir for more than 48 weeks were enrolled. Serum levels of hepatitis B surface antigen (HBsAg), HBeAg and HBV DNA were assessed at 4-week intervals to week 24 and thereafter at 12-week intervals. Virologic response (Y1VR) was defined as an undetectable HBV DNA level at week 48 of therapy. During 48 weeks, HBeAg and HBV DNA level decreased significantly in a biphasic manner and HBsAg level tended to decease. Fifty-three patients (55.8%) attained Y1VR. Pretreatment HBeAg levels were significantly lower in the Y1VR group than in no Y1VR group. At week 4 and 12 of therapy, 25% and 41.4% of patients showed a decrease of HBeAg levels with >0.5 log(10) and >1.0 log(10) from baseline, respectively. These patients achieved more Y1VR than those with less decrease of HBeAg levels (97.7%vs 22.2% and 86.2%vs 29.3%, respectively). HBeAg level at week 12 had higher predictive values for Y1VR than HBV DNA level. Multivariate analysis revealed that a pretreatment HBeAg level of <360 PEIU/mL and the reduction in HBeAg level >1.0 log(10) at week 12 were associated with Y1VR. These results suggest that pretreatment HBeAg level and an early decrease in HBeAg level are useful measurements for predicting one-year virologic response during entecavir treatment.

First Report of Kalanchoe Leaf Scorch Caused by Stemphylium xanthosomatis in Korea

Kalanchoe (Kalanchoe blossfeldiana Poelln.) is widely cultivated in Korea as an ornamental houseplant and succulent garden plant because of its ease of propagation, low water requirements, and wide variety of flower colors. In August 2010, suspected nursery-stage kalanchoe leaf scorch was found at a grower's greenhouses located in Gimhae, Korea. In some greenhouses, 20 to 30%, and occasionally as much as 50%, of the plants were affected. Symptoms on kalanchoe include browning of the leaf margins and yellowing or darkening of tissues between the main leaf veins. As the disease progresses, affected leaves dried up, turned brown, and became brittle. A velvety, blackish olive mold formed on the surface of the dead tissue, followed by plant defoliation. Fresh leaf specimens were collected from infected plants and the causal pathogen was purified with a single-spore isolation technique and transferred onto potato dextrose agar (PDA). Colonies on PDA developed a gray or grayish brown, hairy, velvety mycelium that was mostly immersed and also formed conidia. Conidia were pale to mid brown, oblong, smooth or verruculose, with three to five transverse and one to two longitudinal septa in two to three transverse divisions, and 32 to 55 × 11 to 18 μm. Conidiophores were pale to mid brown, solitary or in fascicles, unbranched or occasionally branched, straight or flexuous, more or less cylindrical but enlarged slightly at one to three apical percurrent proliferations, septate, and 80 to 300 × 2 to 5 μm. A representative isolate of the pathogen was inoculated on kalanchoe leaves for pathogenicity testing. Cultures grown on PDA were flooded with sterile distilled water and after rubbing with an artist's paintbrush with hair bristles, the resulting suspensions were filtered through sterile cheesecloth. Conidial suspensions were adjusted to 2.5 × 10⁴ conidia/ml with sterile distilled water. The leaves of five 1-month-old potted plants were wounded by applying pressure with forceps having serrated teeth, bruising the tissue. Wounded plants were sprayed with a conidial suspension until runoff. Five plants sprayed with sterile distilled water served as controls. The plants were maintained for 48 h at 25°C in a humidity chamber with 100% relative humidity and were then moved to a greenhouse. Symptoms similar to those observed in the farmer's greenhouse developed on wounded leaves within 9 days. The causal pathogen was reisolated from the lesions to prove Koch's postulates. To confirm the identity of the fungus, the complete internal transcribed spacer (ITS) rDNA and glyceraldehyde 3-phosphate dehydrogenase (gpd) gene were amplified and sequenced (1). Amplification of the ITS region generated a 579-bp sequence (GenBank Accession No. HQ840713) and gpd was 558 bp (GenBank Accession No. JF776462). The ITS and gpd sequences were 100% similar to the sequences of Stemphylium xanthosomatis (GenBank Accession Nos. AF442804 and AF443903, respectively). On the basis of symptoms, mycological characteristics, pathogenicity, and molecular data, this fungus was identified as S. xanthosomatis. The type culture of the fungus is stored at the Korean Agricultural Culture Collection (KACC 45812), National Academy of Agricultural Science, Korea. To our knowledge, this is the first report of leaf scorch caused by S. xanthosomatis on kalanchoe in Korea. Reference: (1) M. P. S. Câmara et al. Mycologia 94:660, 2002.

First Report of Root Rot Caused by Sclerotium rolfsii on Daucus carota var. sativa in Southern Korea

Carrot (Daucus carota var. sativa DC.), an important root vegetable, is cultivated widely because of its dietary fiber and beta carotene. In June 2009 and June 2010, a disease suspected as root rot of carrot caused by Sclerotium rolfsii occurred in a 5-ha field in Jinju, Korea. Early symptoms consisted of water-soaked lesions on root and lower stem tissue near the soil line. Infected plants gradually withered and white mycelial mats appeared on the surface of roots. Numerous sclerotia were often produced on stem and root surfaces in contact with the soil. The heavily infected carrots became rotted and blighted and the whole plant eventually died. The freshly isolated pathogenic fungus was grown on potato dextrose agar (PDA) and examined microscopically. Optimum temperature for mycelia growth or sclerotia formation was 25 to 30°C. Numerous globoid sclerotia formed on the PDA after 18 days of mycelial growth. The sclerotia (1 to 3 mm in diameter) were white at first and then gradually turned dark brown. Aerial mycelia usually formed, consisting of many narrow hyphal strands 3 to 9 μm wide. The white mycelium formed a typical clamp connection after 5 days of growth at optimum temperature. To fulfill Koch's postulates, 10 carrot seedlings were inoculated with colonized agar discs (6 mm in diameter) of the causal fungus directly on the root and incubated in a humid chamber at 25°C for 24 h. Ten carrot seedlings were inoculated similarly with agar discs as the control treatment. After this period, the inoculated and noninoculated plants were maintained in a greenhouse. Eight days after inoculation, the disease symptoms seen in the field were reproduced and the fungus was reisolated from the artificially inoculated plants. To confirm identity of the causal fungus, the complete internal transcribed spacer (ITS) rDNA region of the causal fungus was amplified using the primers ITS1 and ITS4 (2) and sequenced. The resulting sequence of 684 bp was deposited in GenBank (Accession No. JF342557). The sequence was 99% similar to sequences of Athelia rolfsii (Sclerotium rolfsii) in GenBank. Cultures of S. rolfsii have been deposited with the Korean Agricultural Culture Collection (KACC 45154), National Academy of Agricultural Science, Korea. On the basis of symptoms, fungal colonies, the ITS sequence, and the pathogenicity test on the host plant, this fungus was identified as S. rolfsii Saccardo (1). To our knowledge, this is the first report of root rot of carrot caused by S. rolfsii in Korea. This disease is highly dependent upon environmental conditions, including warm weather and high humidity. Recent occurrence of the disease suggests that S. rolfsii could spread widely. References: (1) J. E. M. Mordue. CMI Descriptions of Pathogenic Fungi and Bacteria. No. 410, 1974. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, Inc., New York, 1990.

Serum hepatitis B surface antigen levels in the natural history of chronic hepatitis B infection

BACKGROUND  The production of hepatitis B surface antigen (HBsAg) may evolve during long-lasting virus-host interactions in chronic hepatitis B (CHB). The impact of age on HBsAg production remains unclear. AIM  To determine the age-specific distribution patterns of HBsAg and related factors during the natural course of CHB infection. METHODS  Seven hundred and sixty-eight untreated HBsAg carriers were enrolled in the study. The parameters and distribution patterns of HBsAg were evaluated in relation to age and immune phases. RESULTS  The HBsAg levels were significantly lower in the HBeAg-negative stage, with the lowest levels in inactive carriers. The HBsAg tended to decrease from hepatitis to cirrhosis and to hepatocellular carcinoma, and from Child-Pugh class A to B and to C. Age and HBV DNA were independently associated with HBsAg levels. In HBeAg-positive patients, the HBsAg levels were distributed in a triphasic-like decline pattern by 2 logs across age strata. For HBeAg-negative patients, the titres in inactive carriers exhibited a 2-log reduction, but remained unchanged over age strata in patients with HBeAg-negative hepatitis. The ratios of HBsAg/HBV-DNA were highest, but steadily decreased with age in inactive carriers, whereas the levels remained largely unchanged over the entire age strata in patients with HBeAg-negative hepatitis. CONCLUSIONS  Age and HBV DNA levels are independent parameters of HBsAg levels. During the natural course of CHB infection, HBsAg levels decrease with age and disease progression, but the patterns are significantly different between the immune phases of CHB. This information may contribute to our understanding of the immunopathogenesis of chronic hepatitis B and management involving HBsAg quantification.

Genetic analyses of avian influenza viruses in Mongolia, 2007 to 2009, and their relationships with Korean isolates from domestic poultry and wild birds

The present study was conducted to monitor wild birds based on the concern that they could disseminate avian influenza virus (AIV) between Mongolia and Korea, which shares the same migratory flyway. Of 1,528 fecal samples analyzed, 21 low-pathogenic AIV were isolated from 2007 to 2009. Nineteen AIV-positive fecal samples were identified as Anseriformes by DNA bar coding. The most frequently isolated subtype was H3 (61.9%), and the most prevalent hemagglutinin/neuraminidase combination was H3N8 (52.4%). Phylogenetic analysis was performed to assess their genetic relationships with those of domestic poultry and wild birds in Korea. The H3 and H7 surface genes belonged to the Eurasian lineage and clustered together in a group with Korean wild birds and poultry. Most N8 genes clustered phylogenetically with viruses isolated in Eurasia, whereas 1 of the Mongolian viruses and some Korean viruses belonged to the North American lineage. The polymerase acidic protein of the internal gene was not distinguishable from the H5N1 highly pathogenic AIV of the goose/Guangdong/1/1996 (Gs/Gd)-like virus. Our study suggests that Mongolian AIV isolates have evolved with genetically multiple genotypes and are closely related to those of AIV in poultry as well as in wild birds in Korea.

Characterization of Escherichia coli isolates from laying hens with colibacillosis on 2 commercial egg-producing farms in Korea

The present study reports on layer chickens with colibacillosis in 2 commercial egg-producing farms (referred to as farm A and farm B, which were managed by the same owner and were about 1 km apart) in the middle region of the Korean peninsula. The 2 flocks were infected at the initiation of egg laying. They were characterized by no previous clinical signs but sudden mortality (2.7-4.0%), with severe lesions of septicemia and fibrinous polyserositis. Escherichia coli was isolated from the lesions of the infected birds. Serotyping tests identified isolates that belonged to somatic groups O1 (12/17), O46 (2/17), O78 (1/17), and O84 (1/17) or that were unidentified (1/17). Thirteen of 17 E. coli isolates (76.4%) obtained from 11 birds in the 2 flocks showed similar pulsed-field gel electrophoresis patterns that were arbitrarily designated as pattern A. The isolates had high frequencies of putative virulence genes including 100% [fimC (type 1 fimbriae), iucD (aerobactin synthesis), and iss (increased serum survival)], 94.1% [cva/cvi (structural genes of colicin V operon) and vat (vacuolating autotransporter toxin)], 88.2% [irp2, iron-repressible protein (yersinia bactin) synthesis, and fyuA, ferric yersinia uptake], and 82.3% [tsh (temperature-sensitive hemagglutinin)]; astA (encoding a heat-stable cytotoxin associated with enteroaggregative E. coli) was not associated with the enteric disorder. These data suggest that all chickens with colibacillosis on farms A and B were likely infected by E. coli strains that are highly pathogenic in avian species.

First Report of Flyspeck Caused by Zygophiala wisconsinensis on Sweet Persimmon Fruit in Korea

Sweet persimmon (Diospyros kaki L.), a fruit tree in the Ebenaceae, is cultivated widely in Korea and Japan, the leading producers worldwide (2). Sweet persimmon fruit with flyspeck symptoms were collected from orchards in the Jinju area of Korea in November 2010. The fruit had fungal clusters of black, round to ovoid, sclerotium-like fungal bodies with no visible evidence of a mycelial mat. Orchard inspections revealed that disease incidence ranged from 10 to 20% in the surveyed area (approximately 10 ha) in 2010. Flyspeck symptoms were observed on immature and mature fruit. Sweet persimmon fruit peels with flyspeck symptoms were removed, dried, and individual speck lesions transferred to potato dextrose agar (PDA) and cultured at 22°C in the dark. Fungal isolates were obtained from flyspeck colonies on 10 sweet persimmon fruit harvested from each of three orchards. Fungal isolates that grew from the lesions were identified based on a previous description (1). To confirm identity of the causal fungus, the complete internal transcribed spacer (ITS) rDNA sequence of a representative isolate was amplified and sequenced using primers ITS1 and ITS4 (4). The resulting 552-bp sequence was deposited in GenBank (Accession No. HQ698923). Comparison with ITS rDNA sequences showed 100% similarity with a sequence of Zygophiala wisconsinensis Batzer & Crous (GenBank Accession No. AY598855), which infects apple. To fulfill Koch's postulates, mature, intact sweet persimmon fruit were surface sterilized with 70% ethanol and dried. Three fungal isolates from this study were grown on PDA for 1 month. A colonized agar disc (5 mm in diameter) of each isolate was cut from the advancing margin of a colony with a sterilized cork borer, transferred to a 1.5-ml Eppendorf tube, and ground into a suspension of mycelial fragments and conidia in a blender with 1 ml of sterile, distilled water. The inoculum of each isolate was applied by swabbing a sweet persimmon fruit with the suspension. Three sweet persimmon fruit were inoculated per isolate. Three fruit were inoculated similarly with sterile, distilled water as the control treatment. After 1 month of incubation in a moist chamber at 22°C, the same fungal fruiting symptoms were reproduced as observed in the orchards, and the fungus was reisolated from these symptoms, but not from the control fruit, which were asymptomatic. On the basis of morphological characteristics of the fungal colonies, ITS sequence, and pathogenicity to persimmon fruit, the fungus was identified as Z. wisconsinensis (1). Flyspeck is readily isolated from sweet persimmon fruit in Korea and other sweet persimmon growing regions (3). The exposure of fruit to unusual weather conditions in Korea in recent years, including drought, and low-temperature and low-light situations in late spring, which are favorable for flyspeck, might be associated with an increase in occurrence of flyspeck on sweet persimmon fruit in Korea. To our knowledge, this is the first report of Z. wisconsinensis causing flyspeck on sweet persimmon in Korea. References: (1) J. C. Batzer et al. Mycologia 100:246, 2008. (2) FAOSTAT Database. Retrieved from http://faostat.fao.org/ , 2008. (3) H. Nasu and H. Kunoh. Plant Dis. 71:361, 1987. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, Inc., New York, 1990.

Survival rate of H5N1 highly pathogenic avian influenza viruses at different temperatures

The survival rate of Korean H5N1 highly pathogenic avian influenza (HPAI) viruses was investigated at different temperatures under the laboratory conditions. The estimated survival days for a starting viral concentration of 10(6.5) 50% egg infectious dose/0.1 mL were 930, 1,042, and 3,213 d at 4 degrees C; 226, 232, and 293 d at 20 degrees C; and 51, 55, and 58 d at 30 degrees C for A/chicken/Korea/ES/03, A/chicken/Korea/IS/06, and A/chicken/Korea/Gimje/08 (Gimje/08) viruses, respectively. The stability of the Gimje/08 virus was statistically significant compared with the other 2 viruses except for the data between Gimje/08 and A/chicken/Korea/IS/06 virus at 30 degrees C. This result indicated that the survival rate of 3 Korean HPAI viruses is different at various temperatures, which might have partially influenced the large scale of HPAI outbreak in Korea in 2008.

The susceptibility of magpies to a highly pathogenic avian influenza virus subtype H5N1

Korean wild magpies (Pica pica sericea) were intranasally inoculated with highly pathogenic avian influenza (A/Chicken/Korea/ES/03 virus) (H5N1), which was classified as clade 2.5. We estimated viral replication, death after infection, and histology and immunohistochemistry. This species was highly susceptible to severe infection; 100% of birds died within 5 to 8 d. The virus was detected from oropharyngeal (1 to 5 d postinfection) and cloacal (3 to 5 d postinfection) swabs from infected magpies. At necropsy, the prominent lesions were coalescing necrosis of the pancreas with enlargement of livers and spleens. Microscopically, pancreas, brain, heart, adrenal gland, and kidney were most consistently affected with necrotic and inflammatory changes, and viral antigen was frequently demonstrated in the parenchyma of these organs. As a result, Korean wild magpies were very susceptible to avian influenza (H5N1) virus.

Development of a stabilizer for lyophilization of an attenuated duck viral hepatitis vaccine

The live attenuated vaccine against duck viral hepatitis currently available in Korea requires special freezers for storage and transportation with extra costs involved. The development of a lyophilization stabilizer for live attenuated duck viral hepatitis virus (DHV) vaccines, therefore, has been highly recommended for the wider application of the vaccines. Four conventional vaccine stabilizer formulations containing a disaccharide, such as lactose, trehalose, or sucrose, and new formulations containing sorbitol were tested for their efficacy in stabilizing a new attenuated DHV type 3 vaccine candidate under different storage temperatures, 4 and 37 degrees C. The vaccine virus and each stabilizer formulation were combined and submitted to lyophilization and the viability of the virus was measured in 7-d-old specific-pathogen-free chicken embryos by determining the 50% egg lethal dose. Stabilizer formulations containing 2, 4, or 8% sorbitol preserved the viability of the vaccine virus much better than the other stabilizer formulations and 2% sorbitol was the optimal concentration in a standard stabilizing buffer, phosphate glutamate gelatin (0.0038 M KH2PO4, 0.0071 M K2HPO4, 0.0049 M monosodium L-glutamate, and 0.5% gelatin). The results demonstrate that the stabilizer formulation containing 2% sorbitol and 0.5% gelatin can be used for convenient storage and transportation of live DHV vaccines.

CT features of lobular capillary hemangioma of the nasal cavity

BACKGROUND AND PURPOSE

Lobular capillary hemangioma is a benign capillary proliferation of unknown etiology. To our knowledge, no comprehensive review of imaging findings of LCHNC has been presented. Thus, we investigated characteristic CT features of LCHNC.

MATERIALS AND METHODS

This retrospective study included 6 patients (2 men and 4 women; age range, 30-65 years; mean age, 49.2 years) with histologically proved LCHNC. We evaluated the size, site of origin, attenuation on NECT, degree and pattern of enhancement, and bony changes.

RESULTS

The LCHNC lesion was 13.0-45.0 mm (average, 25.0 mm) in diameter. These lesions arose from the inferior turbinate in 5 (83.3%) patients and the anterior nasal septum in 1 (16.7%). Compared with the masticator muscles, the LCHNC lesion was hypoattenuating in 2 (33.3%) and isoattenuating on NECT in 4 (66.7%) patients. In 5 (83.3%) patients, the LCHNC lesion consisted of 2 distinct areas on CECT: a lobular intensely enhancing mass and an iso- or hypoattenuating cap of variable thickness around the intensely enhancing mass. Bony changes included erosion in 3 (50.0%) and displacement in 2 (33.3%) patients.

CONCLUSIONS

CT features of LCHNC consist of an intensely enhancing mass and an iso- or hypoattenuating cap on CECT. The inferior turbinate seems to be a common site of origin, and bony changes are not uncommon features of LCHNC. CT is useful not only in identifying the site of origin and assessing the extent but also in suggesting the nature of LCHNC.

Cancer patients' awareness of clinical trials, perceptions on the benefit and willingness to participate: Korean perspectives

To understand patients' perceptions of clinical trials (CTs) is the principal step in the enrolment of patients to CTs. However, these perceptions in eastern countries are very rare. From 12 February 2007 to 13 April 2007, we consecutively distributed the questionnaire to 842 cancer patients who initiated a first cycle of chemotherapy regardless of each treatment step in the Seoul National University Hospital. Younger age, higher educational degree, higher economic status, and possession of private cancer insurance were related with significantly higher awareness of CTs (P=0.001, P=0.006, P=0.002, and P=0.009, respectively). However, unlike awareness, perceptions on benefits of CTs were not changed according to age, educational degree, and economic status (P=0.709, P=0.920, and P=0.847, respectively). Willingness was also not changed according to age, educational degree, economic status, and private cancer insurance (P=0.381, P=0.775, P=0.887, and P=0.392, respectively). Instead, males and heavily treated patients had more positive perceptions on benefits (P=0.002 and P=0.001, respectively) and more willingness to participate in CTs (OR=1.17, 1.14–2.75: OR=1.59, 1.01–2.51, respectively). In summary, cancer patients' awareness of CTs, perceptions on the benefit in CTs, and willingness to participate are differently influenced by diverse medical and social conditions. This information would be very helpful for investigators to properly conduct CTs in eastern cancer patients.

Asp-Tyr-Leu-Lys tetrapeptide inhibits airway inflammation in toluene-2,4-diisocyanate-induced asthma mice

BACKGROUND

Airway inflammation and remodelling contribute to chronic airway obstruction of asthma. Currently, no medication effectively controls airway remodelling and related vascular changes. Therefore, new strategies need to be developed. The kringle 5 domain has anti-angiogenic activity resulting from the tetrapeptide Lys-Leu-Tyr-Asp (KLYD).

OBJECTIVE

To investigate the therapeutic effect of KLYD and its inverse form Asp-Tyr-Leu-Lys (DYLK) on the inflammation and remodelling of toluene-2,4-diisocyanate (TDI)-sensitization/challenged mice.

METHODS

Cell numbers were measured in the presence of various concentrations of KLYD and DYLK using in vitro endothelial cell proliferation assay. The changes of cell number and the level of vascular endothelial growth factor (VEGF) in bronchoalveolar lavage (BAL) fluid and response to methacholine (MCh) were measured using the in vivo TDI-sensitized/challenged mice model. Muc5ac, smooth muscle actin (SMA) and proliferating cell nuclear antigen (PCNA) protein expression was analysed on trachea and intrapulmonary bronchi using immunohistochemical stain.

RESULTS

Compared with KLYD, DYLK had a greater inhibitory effect on endothelial cell proliferation (P<0.05). Pre-treatment of DYLK showed dose-dependent reduction in the response to MCh (P<0.05) and numbers of inflammatory cells in BAL fluids of TDI-sensitized/challenged mice. TDI induced increases in Muc5ac, SMA and PCNA protein expression and VEGF levels, which were also abolished by DYLK treatment.

CONCLUSIONS

Local administration of DYLK effectively inhibits the airway inflammation and airway remodelling of TDI-sensitized/challenged mice via down-regulation of VEGF. These findings suggest that anti-angiogenic peptide therapies, such as local administration of DYLK, are an effective strategy for the treatment of remodelling in asthma.

Anomalous double peak structure in superconductor/ferromagnet tunneling density of states

We have experimentally investigated the density of states (DOS) in Nb/Ni (S/F) bilayers as a function of Ni thickness, d(F). Our thinnest samples show the usual DOS peak at +/- Delta(0), whereas intermediate-thickness samples have an anomalous "double-peak" structure. For thicker samples (d(F) > or =3.5 nm), we see an inverted DOS, which has previously only been reported in superconductor or weak-ferromagnet structures. We analyze the data using the self-consistent nonlinear Usadel equation and find that we are able to quantitatively fit the features at +/- Delta(0) -- in particular the thickness at which the inversion occurs -- only if we include a large amount of spin-orbit scattering in the model. Interestingly, we are unable to reproduce the subgap structure through the addition of any parameter(s). Therefore, the observed anomalous subgap structure represents new physics beyond that contained in the present Usadel theory.

Feed contaminated with classical swine fever vaccine virus (LOM strain) can induce antibodies to the virus in pigs

In November 2004, antibodies to classical swine fever virus (csfv) were detected in finishing pigs during the annual serological surveillance in Jeju Province, Korea. In addition, csf vaccine viruses (lom strain) had recently been isolated from pigs raised on farms known to have csfv antibody-positive pigs. In contrast with mainland Korea, Jeju Province had been csf free and its pigs had not been vaccinated against csf for more than five years. An epidemiological investigation team from the National Veterinary Research and Quarantine Service investigated the current status of csf prevention on the Korean mainland and in Jeju Province to determine possible routes of introduction of the virus into the province. It was concluded that improperly processed blood meals, manufactured on mainland Korea, had been contaminated with the csf vaccine lom strain, and that the lom strain had been transmitted to pigs fed feed or feedstuffs containing the contaminated meal.

Fluoroscopically guided percutaneous jejunostomy: outcomes in 25 consecutive patients

AIM

To assess the feasibility and safety of fluoroscopically guided percutaneous jejunostomy.

MATERIAL AND METHODS

Between May 1999 and August 2006 percutaneous jejunostomy was attempted in 25 patients. A 5 F vascular catheter (n=20) or a 7.5 F multifunctional coil catheter (n=5) was used to insufflate the jejunum. The distended jejunum was punctured using a 17 G needle (n=19) or a 21 G Chiba needle (n=6) with the inserted catheter as a target. A 12 or 14 F loop feeding tube was inserted after serial dilations. The technical success, complications, 30-day mortality, and in-dwelling period of the feeding tube placement were evaluated.

RESULTS

The technical success rate was 92% (23/25). Technical failures (n=2) resulted from the inability to insufflate the jejunum secondary to failure to pass the catheter through a malignant stricture at the oesophagojejunostomy site and thus subsequent puncture of the undistended jejunum failed, or failure to introduce the Neff catheter into the jejunum. Pericatheter leakage with pneumoperitoneum was a complication in three patients (12%) and was treated conservatively. The 30-day mortality was 13% (3/23); however, there was no evidence that these deaths were attributed to the procedure. Except for four patients who were lost to follow-up and two failed cases, 15 of the 19 jejunostomy catheters were removed because of patient death (n=12) or completion of treatment (n=3), with a mean and median in-dwelling period of 231 and 87 days, respectively.

CONCLUSIONS

Fluoroscopically guided percutaneous jejunostomy is a feasible procedure with a high technical success and a low complication rate. In addition to a 17 G needle, a 21 G needle can safely be used to puncture the jejunum.

Recent Korean isolates of duck hepatitis virus reveal the presence of a new geno- and serotype when compared to duck hepatitis virus type 1 type strains

Duck hepatitis was first reported in 1985 in Korea. The complete nucleotide sequence of two past Korean isolates, DHV-HS and DHV-HSS, isolated in 1994 and 1995, and four recent Korean isolates, AP-03337, AP-04009, AP-04114 and AP-04203 isolated in 2003 and 2004, were determined. Phylogenetic analysis using the 3D protein sequence confirmed that the previously characterized duck hepatitis virus type 1 strains and the six Korean isolates described here constitute a monophyletic group and form two clades/genotypes in which all except the four recent Korean isolates form one group (A) and the recent Korean isolates of 2003 and 2004 constitute a second group (B). Phylogenetic analysis of the VP1 protein supported the division into two different groups. Antisera raised against viruses of group A showed significant neutralizing cross-reaction against a member of the same genotype but not to a strain of group B and vice versa. These results demonstrated that the two genotypes also could be regarded as two different serotypes.

Effects of Homologous and Heterologous Neuraminidase Vaccines in Chickens Against H5N1 Highly Pathogenic Avian Influenza

The 2004 Asian H5N1 epizootic outbreak indicates the urgent need for vaccines against highly pathogenic avian influenza (HPAI) virus. The manufacture of inactivated whole-virus vaccines from HPAI viruses by traditional methods is not feasible for safety reasons as well as technical issues. The low pathogenic avian influenza A/wild bird feces/CSM2/02 (H5N3) virus was used as a heterologous neuraminidase vaccine, and HPAI A/CK/Korea/ES/03 (H5N1) virus was used as a homologous neuraminidase vaccine. Protection efficacy of both vaccines was evaluated by clinical signs, mortality rates, and virus shedding from oropharynx and cloaca of vaccinated chickens after challenge with HPAI A/CK/Korea/ES/03 (H5N1) virus. One dose of 128 hemagglutinin (HA) homologous H5N1 vaccine induced 100% protection in mortality and prevented viral shedding completely after lethal dose virus challenge, whereas one dose of 64 HA unit of heterologous H5N3 vaccine only induced 50% protection in mortality, and it did not prevent viral shedding. However, two doses at a 3-wk interval of 64 HA unit of heterologous H5N3 vaccine as well as one dose of 1024 HA unit of heterologous H5N3 vaccine induced 100% survival rate and could prevent viral shedding completely. Furthermore, we could differentiate the sera of infected birds from those of vaccinated birds by indirect immunofluorescent antibody test. These results suggest that heterologous neuraminidase H5N3 vaccine could be a useful tool for the control of H5N1 HPAI epidemic in poultry.

Retroanastomotic hernia after gastrojejunostomy: US and CT findings with an emphasis on the whirl sign

BACKGROUND

We reviewed ultrasound (US) and computed tomographic (CT) findings of retroanastomotic hernia and established whether such findings are characteristic of retroanastomotic hernia in patients who have undergone gastrojejunostomy.

METHODS

During a recent 10-year period, we encountered 13 consecutive cases of retroanastomotic hernia. Of the patients involved, 11 underwent US, 10 underwent CT, and three underwent small bowel followthrough imaging. The US and CT scans were retrospectively reviewed to determine abnormal findings. Surgical proof was available in all cases.

RESULTS

The efferent loop was herniated through the defect created behind the anastomosis in 10 cases, the efferent and afferent loops in two cases, and the afferent loop in one case. Retroanastomotic hernia was prospectively suggested in 12 of these 13 cases. Among the 10 cases of efferent loop herniation, US and CT signs of retroanastomotic hernia included whirling of mesenteric vessels, jejunal loops, and mesentery in the periumbilical abdomen (10 of 10); mural thickening of herniated bowel loops (six of 10); dilatation of herniated bowel loops (four of 10); decreased peristalsis of herniated bowel loops on US (three of nine); and decreased contrast enhancement of herniated bowel loops on CT (one of seven). In one case, US and CT signs of retroanastomotic hernia of the afferent loop included its dilatation and whirling of a short length of afferent loop behind the anastomosis. In two cases, US and CT signs of retroanastomotic hernia of the afferent and efferent loops included findings of afferent and efferent loop herniations. Three of 13 cases had reversible bowel ischemia, and one had bowel necrosis.

CONCLUSION

Retroanastomotic hernia is an important condition, and the US and CT findings we have described might suggest its diagnosis.

Studies on the development of functional powder from citrus peel

The suitability of citrus peels, generated as a by-product of the juice industry, as a source of antioxidants was investigated. Citrus peel powder was prepared by lyophilizing 70% ethanol extract from citrus peels. Extraction was carried out at room temperature (20 degrees C) for 72 h. The extract was subjected to gamma-irradiation treatment (20 kGy). The aqueous solutions of citrus peel powder were examined for color characteristics and antioxidant potential in terms of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, beta-carotene bleaching and nitrite scavenging activities. There were significant changes in Hunter color values due to irradiation. The a*- and b*-values decreased due to radiation treatment. DPPH radical scavenging, beta-carotene bleaching and nitrite scavenging activities were not affected by irradiation treatment. Nitrite scavenging activity was the highest in the extract at pH 1.2 followed by pH 4.2 and 6.0. These functional properties of the aqueous solution were found to be stable in heat treatment. It could significantly improve oxidative stability of lipids in fish meat system. Based on these results there may be opportunities to use citrus peel powder as a functional component in the food processing industry with gamma irradiation treatment improving its color characteristics without adversely influencing the functional properties.

Highly Pathogenic Avian Influenza in Magpies (Pica pica sericea) in South Korea

Highly pathogenic avian influenza (HPAI) is an extremely infectious, systemic viral disease of birds that produces high mortality and morbidity. HPAI was diagnosed in the three dead magpies (Pica pica sericea) submitted to the National Veterinary Research and Quarantine Service. At necropsy, the prominent lesions were multifocal or coalescing necrosis of the pancreas with enlargement of the livers and spleens. Microscopically, there were severely necrotizing pancreatitis and lymphocytic meningoencephalitis. Influenza viral antigen was also detected in areas closely associated with histologic lesions. Avian influenza virus was isolated from cecal tonsils and feces of the magpies. The isolated virus was identified as a highly pathogenic H5N1, with hemagglutinin proteolytic cleavage site deduced amino acid sequence of QREKRKKR/GLFGAIAG. To determine the pathogenicity of the isolate, eight 6-wk-old specific-pathogen-free chickens were inoculated intravenously with the virus, and all birds died within 24 hr after inoculation. This is the first report of HPAI in magpies.

A pilot study on accelerated sludge degradation by a high-concentration membrane bioreactor coupled with sludge pretreatment

A new sludge treatment process combining a high MLSS membrane bioreactor with sludge pretreatment techniques was studied in pilot-scale experiments. The membrane bioreactor (MBR) was adopted for high efficiency aerobic digestion. The combination of alkaline-ozone treatment of the mixed liquor in the MBR reactor accelerated the biodegradation process by enhancing biodegradability of the sludge. The hydraulic retention time (HRT) of the reactor was set as 3.1 days and the DO level was 1 mg/L on average. After 5 months of operation, the accumulative total solids reduction was more than 70%. Removal efficiency of volatile solids and non-volatile solids were 76% and 54%, respectively. It was found that a considerable portion of the non-volatile solids was dissolved into ions and then flushed out with the effluent. Also, about 41% and 28% of T-N and T-P in the raw sludge were removed although no biological nutrient removal process was adopted. The experiment was run smoothly without significant membrane fouling, even at the relatively high levels of MLSS concentration (11,000-25,000 mg/L). It is concluded that the newly proposed process can significantly increase the sludge reduction efficiency with much shorter retention times.

Acidic and hydrogen peroxide treatment of polyaluminum chloride (PACL) sludge from water treatment

The water treatment sludge including coagulants cannot be easily removed by conventional dewatering methods. The possibility of hydrogen peroxide (H2O2) oxidation as a pretreatment to enhance the dewaterability of polyaluminum chloride (PACl) sludge from water works was investigated. H2O2 treatment alone was not effective but H2O2 treatment under acidic condition significantly reduced both the cake water content and specific resistance to filtration (SRF), indicating the enhancement of dewaterability and filterability. The filterability after acid/H2O2 treatment was comparable to polymer conditioning and even more dewatered cake than polymer conditioning was produced. By H202 combined with sulfuric acid (H2SO4), leached iron caused Fenton's reaction, which showed a potential to significantly reduce the amount of solids mass and to produce more compact cake with higher filterability.

The Vulnerable Attachment Style Questionnaire (VASQ): an interview-based measure of attachment styles that predict depressive disorder

BACKGROUND

The Vulnerable Attachment Style Questionnaire (VASQ) was developed to provide a brief self-report tool to assess adult attachment style in relation to depression and validated against an existing investigator-based interview (Attachment Style Interview--ASI). This paper describes the development and scoring of the VASQ and its relationship to poor support and major depression.

METHOD

Items for the VASQ reflected behaviours, emotions and attitudes relating to attachment relationship style, drawn directly from the ASI. The VASQ was validated against the ASI for 262 community-based subjects. Test-retest was determined on 38 subjects.

RESULTS

Factor analysis derived two factors, labelled 'insecurity' and 'proximity-seeking'. The VASQ insecurity dimension had highest mean scores for those with interview-based Angry-dismissive and Fearful styles and was significantly correlated with degree of interview-based insecurity. The proximity-seeking VASQ scores had highest mean for those with Enmeshed interview attachment style and was uncorrelated with ASI insecurity. VASQ scores were highly correlated with a well-known self-report measure of insecure attachment (Relationship Questionnaire) and text-retest reliability of the VASQ was satisfactory. The total VASQ score and the insecurity subscale proved highly related to poor support and to depressive disorder. This was not the case for the proximity-seeking subscale.

CONCLUSION

The VASQ is a brief self-report measure that distinguishes individuals with attachment styles vulnerable for depressive disorder. The use of the measure for screening in research and clinical contexts is discussed.