Clinical severity of COVID-19 with omicron variant predominance in relation to vaccination status, age, comorbidities- a single center in Selangor, Malaysia

INTRODUCTION

Recently, the rapid surge of reported COVID-19 cases attributed to the Omicron variant of severe acute respiratory syndrome coronavirus (SARS-CoV-2) created an immediate concern across nations. Local information pertaining to the new variant of concern (VOC) is lacking. We aimed to determine the clinical characteristics of COVID-19 during a period of Omicron prevalence among patients hospitalised from February 1 to 21, 2022 at Sungai Buloh Hospital and to estimate the risks of disease progression presumably caused by this variant in association with gender, age, comorbidity, and vaccination status.

MATERIALS AND METHODS

In this retrospective, singlecentered, retrospective cohort study, all hospitalised adults with laboratory-confirmed COVID-19, aged 18 and above, were recruited from February 1 to 21, 2022. Clinical characteristics, investigations, and outcomes were assessed.

RESULTS

A total of 2279 patients aged 18 years and above with laboratory-proven COVID-19 were recruited and analysed, excluding 32 patients owing to incomplete data. Majority of the study population had a mean age of 41.8 ± 17.7, was female-predominant (1329/2279, 58.6%), had completed a primary series of vaccination with a booster (1103/2279, 48.4%), and had no underlying medical conditions (1529/2279, 67.4%). The risk of COVID-19-related disease progression was significantly lower in hospitalised patients under the age of 50 who were female, had no comorbidity, and had completed two doses of the primary series with or without a booster. [respectively, OR 7.94 (95% CI 6.16, 10.23); 1.68 (1.34, 2,12); 2.44 (1.85, 3.22); 2.56 (1.65, 3.97), p< 0.001].

CONCLUSION

During the period of Omicron prevalence, a favourable outcome of COVID-19 was strongly associated with female gender, age below 50, a comorbidity-free condition, and having completed immunization. With this new observation, it could help improve public health planning and clinical management in response to the emergence of the latest VOC.

Invasive salmonella enteritidis infection complicated by colonic perforations and pancytopenia: A case report

Salmonellosis caused by bacterial genus Salmonella is associated with a high morbidity and mortality rate. Salmonellae can be divided into typhoidal serotypes (S. enterica ser. Typhi and S. enterica ser. Paratyphi A) and nontyphoidal Salmonella (NTS) serotypes. The two most common NTS serotypes isolated from human sources were S. enterica ser. Typhimurium and S. enterica ser. Enteritidis. NTS infection can present with diverse clinical manifestations, including gastroenteritis, bacteraemia, septic arthritis, osteomyelitis, and endovascular infection. Intestinal perforation is an extremely rare and potentially fatal complication of severe salmonella infection. Herein, we report a case of invasive S. Enteritidis infection complicated by colonic perforation and pancytopenia. Following a colonic resection, the patient received a prolonged course of antimicrobial therapy and eventually recovered.

CT-guided bone marrow aspirations and biopsies: retrospective study and comparison with blind procedures

PURPOSE

To compare the pathology results of CT-guided and blind bone marrow aspirations and biopsies.

METHODS

Ninety-eight consecutive CT-guided biopsies and 98 age- and gender-matched blind (non-CT-guided) posterior iliac crest bone marrow aspirations and biopsies performed in 2017 were reviewed for adequacy of core biopsies and aspirate smears. CT procedure images and CT abdomen/pelvis images were reviewed to evaluate anatomic features of the posterior ilium and soft tissues. Statistical analysis was performed using a T test, Fisher exact test, and Kruskal-Wallis test.

RESULTS

There was no significant difference in the age and gender of the two groups (p > 0.05). However, the CT-guided group had a higher BMI (p = 0.0049) and posterior soft tissue thickness (p = 0.0016). More CT-guided biopsy samples (CT 93 (95%); blind 77 (79%); p = 0.0006) and aspirate smears (CT 90 (92%); blind 78 (80%); p = 0.042) were categorized as adequate. The CT-guided group had longer core lengths (CT 1.4 ± 0.6 (range 0.3-3.5) cm; blind 1.0 ± 0.60 (range 0-2.6) cm; p = 0.0001). Overall, 131/164 (80%) of the cases had at least one of the described features (slanted posterior ilium (angle > 30°), 30%; rounded posterior ilium, 20%; thick posterior ilium cortex, 13%; focal lesion in posterior ilium, 12%; prior procedure in posterior ilium, 5%; posterior soft tissue thickness > 3 cm, 40%).

CONCLUSION

CT-guided bone marrow procedures were more likely to result in both adequate aspirate smears and biopsy samples and longer core lengths when compared with blind procedures.

Are vital sign abnormalities associated with poor outcomes after emergency department discharge?

To examine association between vital sign abnormalities in the emergency department (ED) and early death after ED discharge, we performed a matched case-control study. Conditional logistic regression showed that presence of any vital sign abnormality at ED discharge was significantly associated with over three-fold increase in likelihood of death within 15 days of ED discharge (OR: 3.06, 95%CI: 2.81-4.48). Even small changes were associated with increased risk: every additional beat increase in heart rate conferred additional risk (OR: 1.04, 95%CI: 1.02-1.06), while every additional oxygen saturation percentage point was protective (0.89, 0.80-0.98). However, none of these vital sign abnormalities was a good predictor of early death; there was poor discrimination and substantial overlap in values between cases and controls.

Extraction of guided wave dispersion curve in isotropic and anisotropic materials by Matrix Pencil method

Guided wave dispersion curves in isotropic and anisotropic materials are extracted automatically from measured data by Matrix Pencil (MP) method investigating through k-t or x-ω domain with a broadband signal. A piezoelectric wafer emits a broadband excitation, linear chirp signal to generate guided waves in the plate. The propagating waves are measured at discrete locations along the lines for one-dimensional laser Doppler vibrometer (1-D LDV). Measurements are first Fourier transformed into either wavenumber-time k-t domain or space-frequency x-ω domain. MP method is then employed to extract the dispersion curves explicitly associated with different wave modes. In addition, the phase and group velocity are deduced by the relations between wavenumbers and frequencies. In this research, the inspections for dispersion relations on an aluminum plate by MP method from k-t or x-ω domain are demonstrated and compared with two-dimensional Fourier transform (2-D FFT). Other experiments on a thicker aluminum plate for higher modes and a composite plate are analyzed by MP method. Extracted relations of composite plate are confirmed by three-dimensional (3-D) theoretical curves computed numerically. The results explain that the MP method not only shows more accuracy for distinguishing the dispersion curves on isotropic material, but also obtains good agreements with theoretical curves on anisotropic and laminated materials.

The Impact of the Shallow-Trench Isolation Effect on Flicker Noise of Source Follower MOSFETs in a CMOS Image Sensor

The flicker noise of source follower transistors is the dominant noise source in image sensors. This paper reports a systematic study of the shallow trench isolation effect in transistors with different sizes under high temperature conditions that correspond to the quantity of empty defect sites. The effects of shallow trench isolation sidewall defects on flicker noise characteristics are investigated. In addition, the low-frequency noise and subthreshold swing degrade simultaneously in accordance to the device gate width scaling. Both serious subthreshold leakage and considerable noise can be attributed to the high trap density near the STI edge. Consequently, we propose a coincidental relationship between the noise level and the subthreshold characteristic; its trend is identical to the experiments and simulation results.

Distribution of the Carbohydrate Antigens, Du-Pan-2 and Ca19-9, in Tumors of the Lung

Aims and background

The carbohydrate chains of malignant cells appear to be related to oncofetal differentiation. The serum levels of CA19-9 have been reported to be evaluated in some patients with lung carcinomas, however, the distribution of carbohydrate antigens were not precisely described. We have investigated in this study the distribution of DU-PAN-2 and CA19-9 antigens in lung tumors.

Methods

Ninety five specimens of lung tumors were selected from surgical specimens. The expression of DU-PAN-2 and CA19-9 were studied by immunohystochemical techniques. The relationship between the expression of these antigens and the classification or the differentiation degree of the tumors were examined.

Results

DU-PAN-2 or CA19-9 antigens were detected in 41 (54%) and 45 (59%) cases of the 76 malignant epithelial tumors investigated. These antigens were detected in all types of malignant epithelial tumors, including squamous cell carcinomas, where they were mainly localized to the entire cell surface of malignant cells. In adenocarcinomas, large cell carcinomas and small cell carcinomas, however, these antigens were commonly detected both on the cell membrane and in the cytoplasm. There was positive correlation between the degree of differentiation and DU-PAN-2, but not CA19-9 expression. Among the non-epithelial tumors investigated, those antigens were detected in pulmonary blastomas but not in mesotheliomas.

Conclusions

Immunohistochemical studies for DU-PAN-2 and CA19-9 are useful for defining characteristics of the lung tumors. DU-PAN-2 could be a marker for differentiating between malignant epithelial tumors and mesotheliomas.

Multistate intermittency on the route to chaos of a semiconductor laser subjected to optical feedback from a long external cavity

We observe experimentally two regimes of intermittency on the route to chaos of a semiconductor laser subjected to optical feedback from a long external cavity as the feedback level is increased. The first regime encountered corresponds to multistate intermittency involving two or three states composed of several combinations of periodic, quasiperiodic, and subharmonic dynamics. The second regime is observed for larger feedback levels and involves intermittency between period-doubled and chaotic regimes. This latter type of intermittency displays statistical properties similar to those of on-off intermittency.

Ethnic disparities in progression to advanced liver disease and overall survival in patients with chronic hepatitis C: impact of a sustained virological response

BACKGROUND

Chronic hepatitis C (CHC) can lead to cirrhosis and hepatocellular carcinoma (HCC). A sustained virological response (SVR) is associated with improved outcomes, however, its impact on different ethnic groups is unknown.

AIM

To evaluate ethnic differences in the natural history of CHC and the impact of SVR.

METHODS

We conducted a cohort study of 8039 consecutive adult CHC patients seen at two medical centres in California between January 1997 and June 2016. Individual chart review confirmed CHC diagnosis.

RESULTS

Asian and Hispanic but not African American patients had significantly higher cirrhosis and HCC incidence than Caucasians. On multivariate analysis, Hispanic ethnicity was independently associated with increased cirrhosis (adjusted HR 1.37, CI, confidence interval 1.10-1.71, P=.006) and HCC risk (adjusted HR 1.47, CI 1.13-1.92, P=.004) compared to Caucasian. Asian ethnicity had a significant association with cirrhosis (adjusted HR 1.28, CI 1.02-1.61, P=.034) and HCC risk (adjusted HR 1.29, CI 0.94-1.77, P=.025). In patients who achieved SVR, Hispanic ethnicity was no longer independently associated with cirrhosis (adjusted HR 1.76, CI 0.66-4.71, P=.26) or HCC (adjusted HR 1.05, CI 0.27-4.08, P=.94); nor was Asian ethnicity (adjusted HR 0.62, CI 0.21-1.82, P=.38 for cirrhosis; 2.01, CI 0.63-6.36, P=.24 for HCC). Similar findings were observed with overall survival among the ethnicities by SVR status.

CONCLUSION

Hispanic and Asian ethnicity was independently associated with increased cirrhosis and HCC risk. Achieving an SVR eliminates the ethnic disparity in liver disease progression and overall survival between Hispanic and Asian vs Caucasian CHC patients.

Effect of Load Deflection on Corrosion Behavior of NiTi Wire

For dental orthodontic applications, NiTi wires are used under bending conditions in the oral environment for a long period. The purpose of this study was to investigate the effect of bending stress on the corrosion of NiTi wires using potentiodynamic and potentiostatic tests in artificial saliva. The results indicated that bending stress induces a higher corrosion rate of NiTi wires in passive regions. It is suggested that the passive oxide film of specimens would be damaged under bending conditions. Auger electron spectroscopic analysis showed a lower thickness of passive films on stressed NiTi wires compared with unstressed specimens in the passive region. By scanning electron microscopy, localized corrosion was observed on stressed Sentalloy specimens after a potentiodynamic test at pH 2. In conclusion, this study indicated that bending stress changed the corrosion properties and surface characteristics of NiTi wires in a simulated intra-oral environment.

Effectiveness and tolerability of simeprevir and sofosbuvir in nontransplant and post-liver transplant patients with hepatitis C genotype 1

BACKGROUND

Hepatitis C virus genotype 1a (HCV-1a), prior treatment, cirrhosis and post-transplant status are historically associated with poor treatment responses. The new oral direct-acting agents appear to be effective and safe in these patients.

AIMS

To evaluate the effectiveness and tolerability of simeprevir and sofosbuvir in a diverse real-life cohort of patients, including difficult-to-treat patients.

METHODS

We conducted a retrospective cohort study in 198 consecutive patients with hepatitis C genotype 1 (148 nontransplant, 50 post transplant), who were treated with simeprevir and sofosbuvir for 12 weeks between December 2013 and December 2014. Primary outcome was sustained virological response with undetectable HCV RNA 12 weeks after completion of therapy (SVR12). Risk factors evaluated for lack of SVR12 included HCV 1a (vs. 1b), prior treatment (vs. none), and cirrhosis (vs. no cirrhosis).

RESULTS

SVR12 rates were similar in non- and post-transplant settings, 82% and 88%, respectively. There were no significant differences in adverse events in patients regardless of cirrhosis or transplant status. On multivariate analysis also inclusive of gender and liver transplant status, negative predictors of SVR12 were having at least 2 or 3 risk factors (OR 0.30, 95% CI 0.10-0.87, P = 0.027 or 0.29, 95% CI 0.09-0.85, P = 0.025, respectively).

CONCLUSION

Simeprevir and sofosbuvir combination is a safe and effective regimen for the treatment of non- and post-transplant patients with traditional risk factors for poor treatment response, unless more than 2 difficult-to-treat risk factors are present.

The triple-phase CT image appearance of post-irradiated livers

Objective To evaluate the sequential CT appearance of the liver after hepatic irradiation and to investigate the correlation between CT findings and radiation-induced hepatic injury.

Material and Methods: The triple-phase CT images of 18 patients with hepatocellular carcinomas (HCC) after hepatic irradiation were retrospectively reviewed (in total 41 CT studies). The high-dose region within the liver was defined as the area receiving more than 90% of the prescribed irradiation dose. The mean radiation dose was 55.5 Gy. Density changes and patterns of enhancement in the high-dose region were classified as three types: type I, constant low-density change in all phases; type II, low-density change in both pre-contrast and arterial phases, and iso-density change in the portal phase; type III, low- or iso-density change in the pre-contrast phase, low- or high-density change in the arterial phase, and persistent high-density change in the portal phase. The interval between completion of radiotherapy and the CT examinations ranged from 9 to 469 days, with a mean of 147 days.

Results: Nine of the 41 CT studies presented with type I, 9 with type II, and 16 with type III CT findings. The mean interval between completion of radiotherapy and the appearance of types I, II, and III CT findings were 74, 183, and 220 days, respectively. The interval was significantly shorter for type I findings than for type II and type III. The difference in interval was not significant between type II and type III. A type I finding with constant low-density change in the high-dose region of the liver was the most common pattern of CT findings within the first 3 months after hepatic irradiation. Either types II or III findings were frequently seen after 3 months.

Conclusion: The sequential CT appearance and the density changes may indicate correlation with the pathogenesis of veno-occlusive disease.

Low-frequency fluctuations in an external-cavity laser leading to extreme events

We experimentally investigate the dynamical regimes of a laser diode subject to external optical feedback in light of extreme-event (EE) analysis. We observe EEs in the low-frequency fluctuations (LFFs) regime. This number decreases to negligible values when the laser transitions towards fully developed coherence collapse as the injection current is increased. Moreover, we show that EEs observed in the LFF regime are linked to high-frequency pulsing events observed after a power dropout. Finally, we prove experimentally that the observation of EEs in the LFF regimes is robust to changes in operational parameters.

First records of parasitic copepods (Crustacea, Siphonostomatoida) from marine fishes in Korea

The knowledge of the biodiversity of parasitic copepods in South Korea is increasing. Interestingly we report here, some parasitic copepods considered as the first record of findings from Korea. Nine species of parasitic copepods (Siphonostomatoida) including six genera of three different families [Caligidae (7), Lernaeopodidae (1), Lernanthropidae (1)] were recovered from eight species of wild fishes in Korea: 1) Caligus hoplognathi Yamaguti & Yamasu, 1959 (♀, ♂) from the body surface of barred knifejaw Oplegnathus fasciatus (Temminck & Schlegel); 2) Caligus lagocephali Pillai, 1961 (♀) from the gills of panther puffer Takifugu pardalis (Temminck & Schlegel); 3) Euryphorus brachypterus (Gerstaecker, 1853) (♀, ♂) from the opercular cavity of Atlantic bluefin tuna Thunnus thynnus (Linnaeus); 4) Euryphorus nordmanni Milne Edwards, 1840 (♀, ♂) from the opercular cavity of common dolphin fish Coryphaena hippurus Linnaeus; 5) Gloiopotes huttoni (Thomson) (♀, ♂) from the body surface of black marlin Istiompax indica (Cuvier); 6) Lepeophtheirus hapalogenyos Yamaguti & Yamasu, 1959 (♀) from the gill filaments of O. fasciatus; 7) Lepeophtheirus sekii Yamaguti, 1936 (♀, ♂) from the body surface of red seabream Pagrus major (Temminck & Schlegel); 8) Brachiella thynni Cuvier, 1830 (♀) from the body surface of longfin tuna or albacore Thunnus alalunga (Bonnaterre); 9) Lernanthropinus sphyraenae (Yamaguti & Yamasu, 1959) (♀) from the gill filaments of moon fish Mene maculata (Bloch & Schneider). Since the female was already reported in Korea, it is a new record for the male of C. hoplognathi. A checklist for the parasitic copepods of the family Caligidae, Lernaeopodidae and Lernanthropidae of Korea is provided.

An unexpected route for otolaryngology bacterial contamination with a Venturi atomizer

BACKGROUND

The Venturi-principle atomizer is a commonly used device in otolaryngology practices. The purpose of this study is to evaluate the possible route of bacterial contamination from the nasal vestibule to the atomizer tip through the jet airflow created during the use of the Venturi atomizer.

METHODS

Thirty nostrils from 15 enrolled volunteers were tested. The aerosols generated by spraying sterilized saline into the nostrils were collected using a specially made aerosol-collecting nozzle cap. The collected samples were sent for bacterial culture, and nasal vestibular swab cultures were performed for comparison.

RESULTS

In the aerosol-exposed group, 18 out of 30 samples (60%) were positive for bacterial growth, confirming the bacterial contamination from the nasal vestibule to the atomizer tip through the reverse jet airflow. The bacteria species in 8 of the 18 positive samples were identical to those from the nasal swab culture results from the same nostril.

CONCLUSION

In ordinary otolaryngology practices, there are significant risks for bacterial contamination from the nasal vestibule to the tip of the Venturi atomizer even without direct contact. Clinicians must be more aware of this pattern of contamination, which has not been reported in the existing literature.

Cardiac transplantation and concomitant coronary artery bypass grafting: our experiences in 11 cases

INTRODUCTION

The shortage of donor hearts for transplantation could be alleviated by including the hearts of older donors. Previous literature revealed similar early and medium-term survival outcomes compared with those of younger donors. This study presents our experience with patients who underwent orthotopic heart transplantation and concomitant coronary artery bypass grafting at our institution.

METHODS

We present our experience with 11 patients with end-stage cardiomyopathy (8 men and 3 women) undergoing orthotopic heart transplantation and concomitant coronary artery bypass grafting from September 2002 to November 2011 at our institute.

RESULTS

All 11 donor organs would otherwise have been rejected, depriving potential recipients of organ transplantation. Two patients received concurrent 2-coronary-artery bypass, and the other 9 patients received concurrent single-coronary-artery bypass during orthotopic heart transplantation. All patients had an uneventful postoperative course, with follow-up completed 3 to 128 months after cardiac transplantation and concomitant coronary artery bypass grafting surgery.

CONCLUSIONS

Our experiences suggest that donor hearts requiring coronary artery bypass grafting, which form a small but significant donor subgroup, can be used effectively and safely when matched to the recipients' age and medical condition.

Accumulation of heavy metals in leaf vegetables from agricultural soils and associated potential health risks in the Pearl River Delta, South China

This study investigated the extent of heavy metal accumulation in leaf vegetables and associated potential health risks in agricultural areas of the Pearl River Delta (PRD), South China. Total concentrations of mercury (Hg), cadmium (Cd), lead (Pb), chromium (Cr) and arsenic (As) were determined in 92 pairs of soil and leaf vegetable (flowering Chinese cabbage, lettuce, pakchoi, Chinese cabbage, loose-leaf lettuce, and Chinese leaf mustard) samples collected from seven agricultural areas (cities). The bioconcentration factors (BCF) of heavy metals from soil to vegetables were estimated, and the potential health risks of heavy metal exposure to the PRD residents through consumption of local leaf vegetables were assessed. Results showed that among the six leaf vegetables, pakchoi had the lowest capacity for heavy metal enrichment, whereas among the five heavy metals, Cd had the highest capacity for transferring from soil into vegetables, with BCF values 30-fold those of Hg and 50-fold those of Cr, Pb and As. Sewage irrigation and fertilization were likely the main sources of heavy metals accumulated in leaf vegetables grown in agricultural areas of the PRD region. Different from previous findings, soil pH had no clear effect on metal accumulation in leaf vegetables. Despite a certain degree of metal enrichment from soil to leaf vegetables, the PRD residents were not exposed to significant health risks associated with consumption of local leaf vegetables. Nevertheless, more attention should be paid to children due to their sensitivity to metal pollutants.

Can iterative reconstruction improve imaging quality for lower radiation CT perfusion? Initial experience

BACKGROUND AND PURPOSE

Initial results using IR for CT of the head showed satisfactory subjective and objective imaging quality with a 20-40% radiation dose reduction. The aim of our study was to compare the influence of IR and FBP algorithms on perfusion parameters at standard and lowered doses of CTP.

MATERIALS AND METHODS

Forty patients with unilateral carotid stenosis post-carotid stent placement referred for follow-up CTP were divided into 2 groups (tube currents were 100 mAs in group A and 80 mAs in group B). Datasets were reconstructed with IR and FBP algorithms; and SNRs of gray matter, white matter, and arterial and venous ROIs were compared. CBF, CBV, and MTT means and SNRs were evaluated by using linear regression, and qualitative imaging scores were compared across the 2 algorithms.

RESULTS

The mean effective radiation dose of group B (2.06 mSv) was approximately 20% lower than that of group A (2.56 mSv). SNRs for ROIs in the dynamic contrast-enhanced images were significantly higher than those for the FBP images. Correlations of the SNRs for CBF, CBV, and MTT across the 2 algorithms were moderate (R² = 0.46, 0.23, and 0.44, respectively). ROIs in gray matter rather than the IR algorithm predicted increasing SNRs in all CBF, CBV, and MTT maps. Two cases of significant restenosis were confirmed in both algorithms. CBV, CBF, and MTT imaging scores did not differ significantly across algorithms or groups.

CONCLUSIONS

Lower dose CTP (20% below normal dose) without IR can effectively identify oligemic tissue in poststenting follow-up. IR does not alter the absolute values or increase the SNRs of perfusion parameters. Other methods should be attempted to improve SNRs in settings with low tube currents.

Multiplex polymerase chain reaction assay for the detection of minute virus of mice and mouse parvovirus infections in laboratory mice

Mouse parvoviruses are among the most prevalent infectious pathogens in contemporary mouse colonies. To improve the efficiency of routine screening for mouse parvovirus infections, a multiplex polymerase chain reaction (PCR) assay targeting the VP gene was developed. The assay detected minute virus of mice (MVM), mouse parvovirus (MPV) and a mouse housekeeping gene (α-actin) and was able to specifically detect MVM and MPV at levels as low as 50 copies. Co-infection with the two viruses with up to 200-fold differences in viral concentrations can easily be detected. The multiplex PCR assay developed here could be a useful tool for monitoring mouse health and the viral contamination of biological materials.

Adverse postoperative outcomes in surgical patients with immune thrombocytopenia

Background

Patients with immune thrombocytopenia (ITP) are likely to have various medical co-morbidities, yet their global features regarding adverse postoperative outcomes and use of medical resources when undergoing major surgery are unknown. The objective of this study was to validate whether ITP is an independent risk factor for adverse postoperative outcomes, and to explore the potential clinical predictors of outcomes after major surgery among patients with ITP.

Methods

A retrospective population-based cohort study was conducted using Taiwan's National Health Insurance Research Database, controlling for preoperative co-morbidities by means of multiple logistic regression. Major postoperative complication and mortality rates, and in-hospital medical costs were analysed.

Results

The study included 11 085 surgical patients with ITP and 44 340 controls without ITP matched for sex, age, and type of surgery and anaesthesia. Surgical patients with ITP had a higher risk of postoperative death (odds ratio (OR) 1·89, 95 per cent confidence interval 1·57 to 2·27), and overall postoperative complications (OR 1·47, 1·39 to 1·56), and increased hospital stay (OR 1·90, 1·80 to 2·01), admission to the intensive care unit (OR 1·73, 1·63 to 1·83) and medical costs (OR 1·89, 1·79 to 1·99). Amount of preoperative platelet and/or red blood cell transfusion, emergency visits and admission to hospital for ITP care were identified as risk factors for adverse postoperative outcomes.

Conclusion

Patients with ITP undergoing surgery are at increased risk of adverse perioperative events, particularly if blood or blood product transfusion are required preoperatively, or the procedure is done as an emergency.

Nonadverse effects on allergenicity of isopentenyltransferase-transformed broccoli

BACKGROUND

Genetically modified organisms (GMOs) provide modern agriculture with improvements in efficiency and the benefits of enhanced food production; however, the potential impact of GMOs on human health has not yet been clarified.

OBJECTIVE

To investigate the allergenicity of isopentenyltransferase (ipt)-transformed broccoli compared with non-GM broccoli.

METHODS

Sera from allergic individuals were used to identify the allergenicity of GM and non-GM broccoli. Immunoglobulin (Ig) binding of different lines of GM and non-GM broccoli was identified using immunoblotting, enzyme-linked immunosorbent assay, and the histamin release assay.

RESULTS

Positive reactions to broccoli (Brassica Oleracea) were observed in 7.02% of individuals. Specific IgE to broccoli and total IgE fro allergic individuals were well correlated. The different tests performed showed no significant differences in the allergenicity of conventionally raised and GM broccoli, indicating the absence of unexpected effects on allergenicity in ipt-transformed plants. Using Western blot analysis we detected heterogeneous IgE-reactive allergenic components in broccoli-allergic sera, but no significant differences between GM an non-GM broccoli were observed in serum from the same patients.

CONCLUSIONS

Our study demonstrates that there are no differences between GM (ipt-transformed) broccoli and non-GM broccoli, as determined by specific IgE in sera from broccoli-allergic patients. This indicates that there were no unexpected effects on allergenicity in this GM broccoli.

Combined heart transplantation and total replacement of thoracic aorta in Marfan's syndrome with recurrent aortic dissection: a case report

It is extremely rare for a patient to need simultaneous heart transplantation (HTx) and replacement of the thoracic aorta. A 23-year-old woman with Marfan's syndrome underwent Bentall's operation and replacement of the ascending aorta (AsA) due to a type A aortic dissection (AD) in August 2001. In March 2005, she began to experience dyspnea on exertion and was found to have a huge pseudoaneurysm at the aortic root, which had caused dehiscence of the aortic conduit. In July 2009, she suffered acute chest pain followed by hypotension and cold sweating. The computed tomography (CT) scan showed a recurrent dissection with a long intimal tear extending from the arch to the mid-portion of the descending thoracic aorta (DTA). Due to technical difficulties in the repair of the aortic root, she was placed on the HTx waiting list. The next day, she received a donor heart and underwent combined HTx and total replacement of the thoracic aorta. Explantation of the heart improved the exposure of the DTA. With the use of a vascular ring connector (Vasoring), the operation was successfully performed without need for a blood transfusion. The patient was still well at 2 years after the operation. Simultaneous replacement of the heart and the whole segment of the thoracic aorta is technically possible in Marfan patients who are complicated with aortic dissection.

Search for charged Higgs bosons in e+e- collisions at [Formula: see text]

A search is made for charged Higgs bosons predicted by Two-Higgs-Doublet extensions of the Standard Model (2HDM) using electron-positron collision data collected by the OPAL experiment at [Formula: see text], corresponding to an integrated luminosity of approximately 600 pb-1. Charged Higgs bosons are assumed to be pair-produced and to decay into [Formula: see text], τντ or AW±. No signal is observed. Model-independent limits on the charged Higgs-boson production cross section are derived by combining these results with previous searches at lower energies. Under the assumption [Formula: see text], motivated by general 2HDM type II models, excluded areas on the [Formula: see text] plane are presented and charged Higgs bosons are excluded up to a mass of 76.3 GeV at 95 % confidence level, independent of the branching ratio BR(H±→τντ ). A scan of the 2HDM type I model parameter space is performed and limits on the Higgs-boson masses [Formula: see text] and mA are presented for different choices of tanβ.

Effect of organic loading rate on organic matter and foulant characteristics in membrane bio-reactor

In this study, the influence of organic loading rate (OLR) on the performance of a membrane bio-reactor (MBR) was investigated. The MBR was operated with 6 different OLRs between 0.5 and 3.0 kg COD/m(3)d. The hydrodynamic parameters of the MBR were kept constant. The hydraulic retention time and sludge retention time were kept at 8h and 40 d respectively. From the experimental investigation, it was found that the removal efficiency of DOC, COD and NH(4)-N decreased when OLRs were increased from 0.5 to 3.0 kg COD/m(3)d. Higher OLRs of 2.75-3.0 kg COD/m(3)d resulted in a higher transmembrane pressure development. The fractionation of organic matters showed more hydrophilic substances with higher OLRs. A detailed organic matter characterization of membrane foulant, soluble microbial product and extracellular polymeric substances showed that bio-polymers type substances together with humic acid and lower molecular neutral and acids were responsible for membrane fouling.

Monitoring peri-therapeutic cerebral circulation time: a feasibility study using color-coded quantitative DSA in patients with steno-occlusive arterial disease

BACKGROUND AND PURPOSE

Intracranial hemodynamics are important for management of SOAD. This study aimed to monitor peri-stent placement intracranial CirT of patients with SOAD.

MATERIALS AND METHODS

Twenty-five patients received stent placement for extracranial ICA stenosis, and 34 patients with normal CirT were recruited as controls. Their color-coded DSAs were used to define the Tmax of selected intravascular ROI. A total of 20 ROIs of the ICA, OphA, ACA, MCA, FV, PV, OV, SSS, SS, IJV, and MCV were selected. rTmax was defined as the Tmax at the selected region of interest minus Tmax at the cervical segment of the ICA (I1 on AP view and IA on lateral view). rTmax of the PV was defined as intracranial CirT. Intergroup and intragroup longitudinal comparisons of rTmax were performed.

RESULTS

rTmax values of the normal cohorts were as follows: ICA-AP, 0.12; ICA-LAT, 0.10; A1, 0.28; A2, 0.53; A3, 0.81; M1, 0.40; M2, 0.80; M3, 0.95; OphA, 0.35; FV, 4.83; PV, 5.11; OV, 5.17; SSS, 6.16; SS, 6.51; IJV, 6.81; and MCV, 3.86 seconds. Before stent placement, the rTmax values of arterial ROIs, except A3 and M3, were prolonged compared with values from control subjects (P < .05). None of the rTmax of any venous ROIs in the stenotic group was prolonged with significance. After stent placement, the rTmax of all arterial ROIs shortened significantly, except A1and M3. Poststenting rTmax was not different from the control group.

CONCLUSIONS

Without extra contrast medium and radiation dosages, color-coded quantitative DSA enables real-time monitoring of peri-therapeutic intracranial CirT in patients with SOAD .

Preventive vertebroplasty for adjacent vertebral bodies: a good solution to reduce adjacent vertebral fracture after percutaneous vertebroplasty

BACKGROUND AND PURPOSE

Adjacent VCF frequently occurs after percutaneous vertebroplasty. Our aim was to evaluate PrVP in the prevention of PVNO-adjacent VCF.

MATERIALS AND METHODS

Radiographs of 68 patients who initially presented with a single-level unhealed fracture and underwent vertebroplasty were retrospectively reviewed for the occurrence of PVNO fracture. Patients in the nonpreventive group (n = 33) underwent TVP only for a vertebra with an unhealed fracture. The preventive group (n = 35) underwent PrVP combined with TVP. We injected bone cement into the caudal part of the superior adjacent vertebra and the cephalic part of the inferior adjacent vertebra to perform PrVP.

RESULTS

The incidences of PVNO fracture in adjacent vertebra next to a vertebra cemented at the patient's first vertebroplasty (within 6 months: 24% versus 3%, P = .012; within 1 year: 30% versus 3%, P = .006; >4 years: 39% versus 3%, P = .006) markedly decreased in the preventive group compared with the nonpreventive group. PVNO fracture was found in 26% of vertebrae adjacent to the first TVP level in the nonpreventive group and in 2% of vertebrae adjacent to a PrVP level in the preventive group after inclusion of all PrVP procedures. Approximately 33% of patients in the nonpreventive group underwent repeat vertebroplasty, mainly due to adjacent fractures. Only 3% of patients in the preventive group underwent repeated procedures. None of the vertebrae cemented for PrVP or TVP developed PVNO refracture.

CONCLUSIONS

Preventive vertebroplasty for the adjacent vertebra combined with TVP for the fractured vertebra is effective in the prevention of propagation of PVNO adjacent fractures, thus reducing the necessity of multiple repeat vertebroplasty procedures.

Effects of spiked metals on the MSW anaerobic digestion

This study aimed to investigate the effects of eight metals on the anaerobic digestion of the organic fraction of municipal solid waste (OFMSW) in bioreactors. Anaerobic bioreactors containing 200 mL MSW mixed completely with 200 m L sludge seeding. Ca and K (0, 1000, 2000 and 6,000 mg L(-1)) and Cr, Ni, Zn, Co, Mo and W (0, 5, 50 and 100 mg  L(-1)) of various dose were added to anaerobic bioreactors to examine their anaerobic digestion performance. Results showed that except K and Zn, Ca (~728 to ~1,461 mg  L(-1)), Cr (~0.0022 to ~0.0212 mg  L(-1)), Ni (~0.801 to ~5.362 mg  L(-1)), Co (~0.148 to ~0.580 mg  L(-1)), Mo (~0.044 to ~52.94 mg  L(-1)) and W (~0.658 to ~40.39 mg  L(-1)) had the potential to enhance the biogas production. On the other hand, except Mo and W, inhibitory concentrations IC(50) of Ca, K, Cr, Ni, Zn and Co were found to be ~3252, ~2097, ~0.124, ~7.239, ~0.482, ~8.625 mg  L(-1), respectively. Eight spiked metals showed that they were adsorbed by MSW to a different extent resulting in different liquid metals levels and potential stimulation and inhibition on MSW anaerobic digestion. These results were discussed and compared to results from literature.

In-Situ TEM Observation of Electromigration Damage by Surface or Interface Diffusion in Al and Al Alloy Films

In-situ transmission electron microscope (TEM) electromigration damage (EMD) tests were performed on pure Al films which were thermally evaporated onto oxidized silicon wafers under different deposition conditions. Three different aluminum alloy films, Al-2wt%Cu, Al-8wt%Cu, and Al-2wt%Cu-lwt%Si were also examined. TEM images were recorded photographically and by a video camcorder. The sample stripes were stressed by a high DC current density (≈1.5 MA/cm2). A linear temperature ramp (5°C/min) was supplied by an external, computer controlled heater. The morphology of EMD-induced voids was found to be strongly dependent on microstructure. In small grain size Al stripes, EMD occurred by the formation of void “fingers” which propagated in an almost random manner. In large grain size Al and Al alloy stripes, the EMD-elongated voids propagated approximately parallel to each other and along the field direction. They were preceded with clearly identifiable local thinning. The thinned regions often had crystallographic edges. Contrary to the commonly held belief that EMD occurs only by a grain boundary diffusion mechanism, the present study clearly shows that surface or interface diffusion was the dominant, latter stage EMD failure mode in large grain size films.

Current status of Barrett's esophagus research in Asia

In Western countries, the epidemiology of esophageal cancer has changed considerably over the past decades with a rise in the ratio of adenocarcinoma to squamous cell carcinoma. Although the prevalence of gastroesophageal reflux is increasing in Asia, the prevalences of Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) have remained low in most Asian countries. The Asian Barrett's Consortium recently conducted a review of published studies on BE from Asia to assess the current status of BE research in Asia, and to recommend potential areas for future BE research in the region. Differences in study design, enrolled population, and endoscopic biopsy protocols used have led to substantial variability in the reported BE prevalence (0.06% to 19.9%) across Asia. In particular, some Japanese studies used diagnostic criteria that differed considerably from what was used in most Asian studies. As in Western countries, increased age, male sex, tobacco smoking, reflux symptoms, and erosive esophagitis have been found to be risk factors for BE in several case-control studies from Asia. The Prague C and M criteria, developed to provide better interobserver reliability in diagnosis and grading of BE, are currently under extensive evaluation in the Asian population. There is a need for standardized protocols for endoscopic and histopathologic diagnosis before initiating collaborative projects to identify etiologic determinants of BE and its ensuing malignant transformation. At present, data regarding the management and long-term outcome of BE are extremely limited in Asia. More studies of BE in this geographic area are warranted.

Treatment performance and microbial characteristics in two-stage membrane bioreactor applied to partially stabilized leachate

A two-stage membrane bioreactor system was applied to the treatment of partially stabilized leachate from solid waste landfill in Thailand. In the system, an anoxic tank with incline tube for biomass separation from re-circulated sludge is followed by a second-stage aerobic tank in which a direct submerged hollow-fiber membrane module is used for solid-liquid separation. During steady operation of 200 days, BOD, COD, NH3 and TKN removals were found to be 99.6, 68, 89 and 86% respectively. Determination of nitrogen transforming bacteria by fluorescent in-situ hybridization technique revealed a slightly higher percentage of nitrifying bacteria in the aerobic tank and a higher percentage of denitrifying bacteria in the anoxic tank respectively. Anammox-like bacteria were also detected at relatively high percentage.

Postischemia myocardial injury in coronary artery bypass patients (PP6)

PURPOSE

To investigate the reperfusion injury of the myocardium in patients undergoing elective coronary artery bypass surgery (CABG) with cardiopulmonary bypass (CPB), we monitored the blood levels of troponin I (TNI), white blood cells, oxygen radicals, malondialdehyde, and myeloperoxidase seeking to define the relationship between the CABG-induced systemic inflammation and myocardial injury.

MATERIALS AND METHODS

We selected 10 patients undergoing primary CABG with CPB at moderate hypothermia and cardioplegic arrest concomitant with intermittent warm blood cardioplegia. We compared all data with their own baseline values to study the reperfusion injury. After release of the aortic clamp, blood was drawn from the coronary sinus, via a catheter placed through the right atrium. We measured plasma levels of inflammatory mediators, such as malondialdehyde, myeloperoxidase, oxygen radicals, and the myocardium injury parameter of TNI.

RESULTS

Patients showed no difference concerning aortic clamp time. TNI increased significantly at 1, 15, and 30 minutes after the onset of reperfusion. Blood levels of white blood cells, oxygen radicals, malondialdehyde, and myeloperoxidase also increased significantly with reperfusion time.

CONCLUSIONS

Reperfusion of ischemic myocardium induced increased TNI, which may be related to the systemic inflammatory responses induced by ischemia and reperfusion of the myocardium among patients undergoing elective coronary bypass surgery.

Narrow-band imaging with magnifying endoscopy for the screening of esophageal cancer in patients with primary head and neck cancers

BACKGROUND AND STUDY AIM

Although narrow-band imaging (NBI) in endoscopy can improve detection of early-stage esophageal malignancies in patients with head and neck cancers, false-positive results may be obtained in areas with nonspecific inflammatory changes. This study evaluated the feasibility of primary screening with NBI and magnification for the presence of esophageal malignancies in these cancer patients.

PATIENTS AND METHODS

Sixty-nine patients with documented head and neck cancers were enrolled from April 2008 to January 2009. All patients underwent a meticulous endoscopic examination of the esophagus using a conventional white-light system followed by re-examination using the NBI system and final confirmation with NBI plus magnification.

RESULTS

Twenty-one patients (30.4 %) were confirmed to have esophageal neoplasia. Among these 21, 16 (76.2 %) had synchronous lesions, 9 (42.9 %) were asymptomatic, and 10 (47.6 %) had early-stage neoplasia. The incidence of multiple esophageal neoplasia was 57.1 %. NBI was more effective than conventional endoscopy in detecting neoplastic lesions (35 lesions in 21 patients vs. 22 lesions in 18 patients) and was particularly effective in patients with dysplasia (13 lesions in 9 patients vs. 3 lesions in 3 patients). The sensitivity and accuracy of detection were 62.9 % and 64.4 % for conventional endoscopy, 100 % and 86.7 % for NBI alone, and 100 % and 95.6 % for NBI with high magnification, respectively.

CONCLUSIONS

Compared with current approaches, NBI followed by high magnification significantly increases the accuracy of detection of esophageal neoplasia in patients with head and neck cancers. The result warrants conducting prospective randomized controlled study to confirm its efficacy.

Unrelated haematopoietic stem cell transplantation in Taiwan and beyond

Since its inception in October 1993, the world-renowned Buddhist Tzu Chi Marrow Donor Registry has facilitated more than 1800 cases of stem cell donations for patients in 27 countries to date. Under the auspices of the Buddhist Tzu Chi Stem Cells Center (BTCSCC), the Registry (> 310,000 donors) offers, on average, one case of stem cell donation every day to national or international transplantation community. The accomplishment of the Registry stems from the philosophy and spirit of giving without reward that was inspired by its founder Dharma Master Cheng Yen, the Samaritan devotions of selfless voluntary stem cell donors and the efforts from a dedicated network of volunteer workers. Demographically speaking, slightly less than one third of the donations are provided to domestic patients and the rest to mainland China and countries in Asia, North America, Europe, Middle East, Oceania, and South Africa. While most of the patients belong to the Oriental ethnic group, a few of the patients are non-Oriental. In addition to the Registry, a non-profit umbilical cord blood (UCB) bank is operating since 2002 to provide a complimentary role for patients unable to identify appropriate bone marrow stem cell donors in the Registry in time. To date, with an inventory of over 12,000 units of UCB cryopreserved in the Tzu Chi Cord Blood Bank, 47 units have been employed in 37 cases of transplantation for both paediatric and adult patients domestically and internationally. The fact that Buddhist Tzu Chi Marrow Donor Registry and Cord Blood Bank are established and operating without governmental financial support is unique and special. To facilitate haematopoietic stem cells to its domestic patients experiencing financial burdens, the BTCSCC offers financial aids to the underprivileged for their medical relief. This humanitarian approach and compassion is definitely a role model for many countries in the world.

Baculovirus-derived hemagglutinin vaccine protects chickens from lethal homologous virus H5N1 challenge

Since outbreaks of highly pathogenic avian influenza (HPAI) in both human and poultry from 2003, it is critical to have effective vaccines. A cDNA fragment coding the entire hemagglutinin (HA) gene derived from an H5N1 strain (A/duck/China/E319-2/03) was cloned and expressed using the baculovirus system. Two weeks after receiving two doses of recombinant HA (rHA) vaccines, chickens develop high antibody response for hemagglutination inhibition (HI) at titer 7.2 log(2). Challenge studies revealed that vaccinated chickens with HI titers greater than 3 log(2) could have immunoprotection against the same HPAI H5N1 strain virus challenge through intranasal route. Additionally, HI titer of 5 log(2) determined whether the live viruses could not be detected from oropharyngeal, cloacal discharge or in tissues. This result suggests that the rHA expressed from baculovirus system could be a candidate for the development of a safe and efficient subunit vaccine for HPAI (H5N1).

Characterization of apoptosis induced by grouper iridovirus in two newly established cell lines from barramundi, Lates calcarifer (Bloch)

Two new cell lines have been established from the muscle and swim bladder tissues of barramundi, Lates calcarifer, and designated as BM (barramundi muscle) and BSB (barramundi swimbladder), respectively. The cells multiplied well at 28 degrees C in Leibovitz's L-15 medium supplemented with 10% foetal bovine serum, and have been continuously subcultured more than 100 times to date. Morphologically, BM cells were mostly fibroblastic, whereas BSB were mostly epithelial. Both cell lines were susceptible to grouper iridovirus (GIV) and displayed characteristics of apoptosis after viral infection. The induction of apoptosis was further assayed in GIV-infected BM and BSB cells by various methods. The inhibition of cell growth by GIV was demonstrated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. Morphological observations revealed typical apoptotic features in the infected cells, including cell shrinkage and rounding, chromosome condensation and formation of apoptotic body-like vesicles. Chromosome fragmentation was detected by DNA laddering and TUNEL assays. Finally, the appearance of phosphotidylserine on the outer leaflet of apoptotic cell membranes was confirmed by annexin V staining. This is the first report of apoptosis induced by GIV in fish cells.

Characteristics and photocatalytic activity of TiO2 thin film sensitized with a porphyrin dye

In this study, a novel porphyrin dye, 5, 10, 15, 20-tetraphenyl-21H, 23H-porphine nickel (TPPN) doped TiO2 (TiO2/TPPN) thin film with visible light respondency was prepared using a sol-gel method and characterized with XRD, SEM, UV-Vis instruments. The observation showed that the absorption edge of TPPN dye-doped thin film shifted into the visible light region. The photocatalytic indigo carmine degradation results showed that under visible light irradiation (lambda > 400 nm) for 6 hrs, the photocatalytic activity of TiO2 thin film sensitized with 200 microM of TPPN dye showed the best performance, with an indigo degradation ratio up to 96%. Moreover, the TiO2/TPPN thin film showed a relevant photocatalytic bactericidal effect on Erwinia carotovora subsp. carotovora 7 induced vegetable soft rot disease in the visible spectral region. Evidence for the photocatalytic disinfection technique against a plant pathogen under visible light irradiation will have potential for direct application in future control of plant diseases in irrigation water systems.

Bilateral traumatic carotid-cavernous fistulae: Strategies for endovascular treatment

BACKGROUND

Most traumatic carotid-cavernous fistula/e (TCCF) are unilateral, and simultaneous bilateral TCCF are uncommon. The purpose of this study was to evaluate the angiographic architecture of bilateral TCCF and report our experience with their endovascular management.

METHOD

Over 15 years, 252 consecutive patients with TCCF were referred to our institute for endovascular treatment. Bilateral TCCF occurred in 5 men and 2 women with a mean age of 31 years. The angiographic architectures of bilateral TCCF were evaluated with cerebral angiography. All patients underwent a single session of transarterial embolisation by using various permanent embolic materials and were followed up clinically or with angiography for a mean of 22 months (range 9-36 months).

FINDINGS

All patients presented with neuro-ophthalmic symptoms and signs. No new instances of cerebrovascular ischemia or intracranial haematoma resulted from bilateral TCCF. All fistulae were associated with partial arterial steal and were successfully occluded by using a detachable balloon and/or a detachable coil with or without a liquid adhesive. Of 14 TCCF, 9 were completely obliterated with preserved flow of the internal carotid artery (ICA). In the other 5 fistulae, the ICA had to be sacrificed to achieve occlusion because the anatomy of the fistula was complex. All fistula related symptoms resolved immediately or gradually during clinical follow up. No clinically significant procedure related neurological complications or recurrent fistulae were observed.

CONCLUSIONS

All bilateral TCCF were associated with a partial arterial steal phenomenon. Single session endovascular treatment using various embolic materials was effective in managing these high-flow fistulae. In all patients, it was possible to preserve one or both ICAs.

Review article: drug hepatotoxicity

BACKGROUND

Drug toxicity is the leading cause of acute liver failure in the United States. Further understanding of hepatotoxicity is becoming increasingly important as more drugs come to market.

AIMS

(i) To provide an update on recent advances in our understanding of hepatotoxicity of select commonly used drug classes. (ii) To assess the safety of these medications in patients with pre-existing liver disease and in the post-liver transplant setting. (iii) To review relevant advances in toxicogenomics which contribute to the current understanding of hepatotoxic drugs.

METHODS

A Medline search was performed to identify relevant literature using search terms including 'drug toxicity, hepatotoxicity, statins, thiazolidinediones, antibiotics, antiretroviral drugs and toxicogenomics'.

RESULTS

Amoxicillin-clavulanic acid is one of the most frequently implicated causes of drug-induced liver injury worldwide. Statins rarely cause clinically significant liver injury, even in patients with underlying liver disease. Newer thiazolidinediones are not associated with the degree of liver toxicity observed with troglitazone. Careful monitoring for liver toxicity is warranted in patients who are taking antiretrovirals, especially patients who are co-infected with hepatitis B and C. Genetic polymorphisms among enzymes involved in drug metabolism and HLA types may account for some of the differences in individual susceptibility to drug hepatotoxicity.

CONCLUSIONS

Drug-induced hepatotoxicity will remain a problem that carries both clinical and regulatory significance as long as new drugs continue to enter the market. Future results from ongoing multicentre collaborative efforts may help contribute to our current understanding of hepatotoxicity associated with drugs.

Characterization of an H5N1 avian influenza virus from Taiwan

In 2003, an avian influenza (AI) virus of H5N1 subtype (A/Duck/China/E319-2/03; Dk/CHN/E319-2/03) was isolated from a smuggled duck in Kinmen Island of Taiwan. Phylogenetic analysis and pairwise comparison of nucleotide and amino acid sequences revealed that the virus displayed high similarity to the H5N1 viruses circulating in Asia during 2004 and 2005. The hemagglutinin (HA) protein of the virus contained multiple basic amino acid residues (-RERRRKR-) adjacent to the cleavage site between the HA1 and HA2 domains, showing the highly pathogenic (HP) characteristics. The HP phenotype was confirmed by experimental infection of chickens, which led up to 100% mortality within 24-72h postinfection. The virus replicated equally well in the majority of organs of the infected chickens with titers ranging from 10(7.5) to 10(4.7) 50% embryo lethal dose (ELD50) per gram of tissue. In a mouse model the virus exhibits low pathogenic characteristics with a lethal infection observed only after applying high inoculating dose (>or=10(7.6) ELD50) of the virus. The infectious virus particles were recovered only from the pulmonary system including trachea and lungs. Our study suggests that ducks infected with H5N1 AIV of HPAI pathotype showing no disease signs can carry the virus silently and that bird smuggling represent a serious risk for H5N1 HPAI transmission.