Investigation of Trehalose Supplementation Impacting Campylobacter jejuni and Clostridium perfringens from Broiler Farming

In 2006, the European Commission banned the use of antibiotic promoters in animal feed. However, there is a new situation in poultry disease where it is necessary to study feed additives, which can overcome the diseases that were previously controlled through the addition of antibiotics and antimicrobial growth promoters in the feed. Therefore, trehalose was investigated to determine whether it impacts the growth performance and pathogenic bacteria (C. jejuni and C. perfringens) inoculation in broilers. In the first experiment, the tolerance of broilers to the addition of trehalose to their feed was investigated. There was no significant difference (p > 0.05) in body weight changes, daily weight gain, feed intake or feed conversion ratio during the feeding period. Within a 35-day feeding period, it was concluded that a trehalose dosage up to 10% does not exert a negative effect on broiler farming. Moreover, there was no significant difference (p > 0.05) in the broilers' growth performance, as well as C. jejuni and C. perfringens counts in the intestines and feces of broilers observed over a 5-week feeding period. However, Lactobacillus counts significantly increased in these groups with 3% and 5% trehalose supplementation. The findings indicate that trehalose supplementation in the feed cannot directly decrease C. jejuni and C. perfringens counts but may enhance gut health by raising Lactobacillus counts in chicken gut, particularly when enteropathogenic bacteria are present.

Genetic diversity of avian paramyxoviruses isolated from wild birds and domestic poultry in Taiwan between 2009 and 2020

Avian paramyxoviruses (APMVs) belonging to the subfamily Avulavirinae within the family Paramyxoviridae. APMVs consist of twenty-two known species and are constantly isolated from a wide variety of avian species around the world. In this study, the APMV isolates obtained from wild birds and domestic poultry during 2009–2020 in Taiwan were genetically characterized by phylogenetic analysis of their complete fusion protein gene or full-length genome. As a result, 57 APMV isolates belonging to seven different species were obtained during this period and subsequently identified as APMV-1 (n=17), APMV-2 (n=1), APMV-4 (n=25), APMV-6 (n=8), APMV-12 (n=2), APMV-21 (n=2) and APMV-22 (n=2). Sanger sequencing was performed to provide 22 full-length genome sequences and 35 complete fusion protein gene sequences for the APMV isolates. Phylogenetic analysis showed that the recovered viruses were closely related to Eurasian strains, except five class I APMV-1 and four APMV-4 isolates were related to North America strains. Our findings provided more evidence for the intercontinental transmission of APMVs between Eurasia and North America by wild birds. In addition, according to the criteria of the classification system based on complete fusion protein gene sequences, three novel genotypes within APMV-2, APMV-12, and APMV-22 were identified. Together, this investigation provided a broader perspective on the genetic diversity, evolution, and distribution of APMVs in multiple avian host species sampled in Taiwan.

Phylogenetic analysis of avian paramyxoviruses 1 isolated in Taiwan from 2010 to 2018 and evidence for their intercontinental dispersal by migratory birds

Avian paramyxovirus 1 (APMV-1), synonymous with Newcastle disease virus (NDV), is a worldwide viral agent that infects various avian species and responsible for outbreaks of Newcastle disease. In this study, 40 APMV-1 isolates collected from poultry, migratory birds, and resident birds during 2010-2018 in Taiwan were characterized genetically. Our phylogenetic analysis of complete fusion protein gene of the APMV-1 isolates revealed that 39 of the 40 Taiwanese isolates were closely related to APMV-1 of class I genotype 1 or class II genotypes I, VI or VII, and one isolate belonged to a group that can be classified as a novel genotype 2 within class I. The fusion protein gene sequences of a branch (former 1d) nested within class I sub-genotype 1.2 were closely related to those isolated from wild birds in North America. Viruses placed in class II sub-genotype VI.2.1.1.2.1 and sub-genotype VI.2.1.1.2.2 were the dominant pigeon paramyxovirus 1 (PPMV-1) circulating in the last decade in Taiwan. All the Newcastle disease outbreak-associated isolates belonged to class II sub-genotype VII.1.1, which was mainly responsible for the present epizootic of Newcastle disease in Taiwan. We conclude that at least five sub/genotypes of APMV-1 circulate in multiple avian host species in Taiwan. One genetically divergent group of APMV-1 should be considered as a novel genotype within class I. Migratory birds may play an important role in intercontinental spread of lentogenic APMV-1 between Eurasia and North America.

Novel avian metaavulavirus isolated from birds of the family Columbidae in Taiwan

Avian paramyxoviruses (APMVs) consist of twenty known species and have been isolated from domestic and wild birds around the world. In 2009, the isolate APMV/dove/Taiwan/AHRI33/2009 was isolated from swabs of red turtle doves (Streptopelia tranquebarica) during active surveillance of avian influenza in resident birds in Taiwan, and it was initially identified as paramyxovirus based on electron microscopy. Hemagglutination inhibition assays indicated antigenic heterogeneity of AHRI33 with the known APMV-1, -2, -3, -4, -6, -8, and -9 species, only showing weak but measurable cross-reactivity with APMV-7. Pathogenicity ICPI test revealed that the virus was avirulent for chickens. The AHRI33 virus genome revealed a typical APMV structure consisting of six genes 3'-NP-P-M-F-HN-L-5', and the length of the genome was 16,914 nucleotides, the third longest among the members of the subfamily Avulavirinae. Estimates of the nucleotide sequence identities of the genome between each prototype of APMVs had shown AHRI33 to be more closely related to APMV-7 than to the others, with a sequence identity of 62.8%. Based on topology of the phylogenetic tree of RdRp genes and the branch length between the nearest node and the tip of the branch, AHRI33 met the criteria for designation as distinct species. Together, the data suggest that the isolate APMV/dove/Taiwan/AHRI33/2009 should be considered as the prototype strain of the new species Avian metaavulavirus 21 in the genus Metaavulavirus in the subfamily Avulavirinae.

Influenza B viruses in pigs, Taiwan

Background

Influenza B viruses (IBVs) have never been isolated from natural‐infected pigs in clinical cases, although the susceptibility of domestic pigs to experimental IBV infections had been confirmed as well as IBV‐specific antibodies were detected from pigs under natural and experimental conditions.

Objectives

We aimed to assess and investigate the activities for infection and circulation of IBVs in pigs.

Methods

Annual active surveys for influenza have been implemented on swine populations in Taiwan since July 1998. Nasal swabs, trachea, lungs, and blood from pigs were tested using virological and serological assays for influenza. Gene sequences of influenza viral isolates were determined and characterized. Preliminary sero‐epidemiological data for influenza virus were investigated.

Results

Three strains of IBV were isolated and identified from natural‐infected pigs in 2014. Genetic characterization revealed the highest identities (>99%) of molecular sequence with the contemporary IBVs belonged to the B/Brisbane/60/2008 genetic clade of Victoria lineage in the phylogenetic trees for all 8 genes. IBV‐specific antibodies were detected in 31 (0.2%; 95%CI: 0.1%‐0.2%) of 15 983 swine serum samples from 29 (2.8%; 95%CI: 1.9%‐3.9%) of 1039 farm visits under annual active surveys from 2007 through 2017. Seropositive cases have been found sparsely in 1‐5 of test prefectures every year except 2015 and 2017 as well as scattered loosely over 26 townships/districts of 11 prefectures in Taiwan cumulatively in 11 years.

Conclusions

Influenza B viruse infections from humans to pigs remained sporadic and accidental currently in Taiwan but might have paved potential avenues for newly emerging zoonotic influenza in the future.

Development of a quantitative real-time RT-PCR assay for detecting Taiwan ferret badger rabies virus in ear tissue of ferret badgers and mice

In 2013, the first case of Taiwan ferret badger rabies virus (RABV-TWFB) infection was reported in Formosan ferret badgers, and two genetic groups of the virus were distinguished through phylogenetic analysis. To detect RABV-TWFB using a sensitive nucleic acid-based method, a quantitative real-time reverse transcription polymerase chain reaction targeting the conserved region of both genetic groups of RABV-TWFB was developed. This method had a limit of detection (LOD) of 40 RNA copies/reaction and detected viral RNA in brain and ear tissue specimens of infected and dead Formosan ferret badgers and mice with 100% sensitivity and specificity. The mean viral RNA load detected in the ear tissue specimens of ferret badgers ranged from 3.89 × 10⁸ to 9.73 × 10⁸ RNA copies/g-organ, which was 111-fold to 2,220-fold lower than the concentration detected in the brain specimens, but 2,000-fold to 5,000-fold higher than the LOD of the assay. This highly sensitive technique does not require facilities or instruments complying with strict biosafety criteria. Furthermore, it is efficient, safe, and labor-saving as only ear specimens need be sampled. Therefore, it is a promising technique for epidemiological screening of Taiwan ferret badger rabies.

Using the chronic kidney disease guidelines to evaluate the renal safety of tenofovir disoproxil fumarate in hepatitis B patients

BACKGROUND

Renal dysfunction remains an issue in tenofovir disoproxil fumarate (TDF) for chronic hepatitis B (CHB) patients.

AIM

To evaluate renal safety of TDF according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines.

METHODS

We retrospectively recruited CHB patients who received either TDF or entecavir (ETV) monotherapy from January 2008 to August 2015. After excluding confounding conditions, 253 patients who received TDF were randomly matched 1:2 with 506 patients who received ETV through the propensity scores, which consisted of age, gender, cirrhosis, chronic kidney disease (CKD) and estimated glomerular filtration rate (eGFR). Renal function deterioration was defined as a drop in GFR category accompanied with a ≥25% eGFR decline. Cumulative incidences of and hazard ratios (HRs) for renal dysfunction were analysed.

RESULTS

The mean eGFR decline was significantly greater in the TDF group over 48 months (TDF vs ETV: 15.73 mL/min/1.73 m² , 95% confidence interval [CI]: 13.76-17.70 vs 5.96 mL/min/1.73 m² , 95% CI: 4.72-7.19; P < 0.001). The cumulative incidence of renal function deterioration was significantly higher in the TDF group (TDF vs ETV: 11.1%, 95% CI: 7.4-14.8 vs 1.7%, 95% CI: 1.0-2.4; P < 0.001). After adjusting for age, pre-existing CKD and diabetes, TDF was independently associated with an increased risk of renal function deterioration (HR 5.36, 95% CI: 2.16-13.35; P < 0.001). Pre-existing CKD (HR 6.71, 95% CI: 2.25-17.65), proteinuria (HR 3.39, 95% CI: 1.23-9.39), and haematuria (HR 4.25, 95% CI: 1.32-13.68) were also independent factors of renal dysfunction.

CONCLUSION

By following the KDIGO guidelines, we confirmed that TDF was associated with a higher risk of renal dysfunction as compared to ETV.

Safety, efficacy and immunogenicity evaluation of the SAG2 oral rabies vaccine in Formosan ferret badgers

Since 2013, rabies cases have been reported among Formosan ferret badgers in Taiwan, and they have been shown to be the major reservoirs for Taiwanese enzootics. To control and eradicate rabies, the authorities plan to implement a vaccination programme. Before distributing live vaccines in the field, this study assessed the safety, efficacy, and immunogenicity of SAG2 vaccine on ferret badgers by direct oral instillation. After application of 109 TCID50/dose, no virus was excreted into the oral cavity 1-7 days post-application, and safety was also satisfactorily verified over a 266-day period. Moreover, despite the low level of rabies virus neutralising antibodies induced after vaccination of a 108 TCID50/dose, the efficacy assessment revealed a 100% survival rate (15/15) of vaccinees and an 87.5% fatality rate (7/8) in control animals after a challenge on the 198th day post-vaccination. The immunisation and protection rates obtained more than 6 months after a single vaccination dose demonstrated that SAG2 is an ideal vaccine candidate to protect Formosan ferret badgers against rabies in Taiwan.

Incidence and Antimicrobial Susceptibility to Clostridium perfringens in Premarket Broilers in Taiwan

Clostridium perfringens infection causes subclinical and clinical necrotic enteritis in poultry flocks, and it is estimated to result in US$2 billion of losses worldwide every year. The aims of this study were to determine the incidence, toxin types, and antimicrobial resistance levels to C. perfringens isolated from premarket, 5-wk-old, clinically healthy broiler chickens in Taiwan, and to examine the relationships between intestinal lesions and the numbers of C. perfringens in intestinal contents. In total, 435 samples of chicken ileum contents were collected from 98 broiler farms during June 2012 to February 2013. The C. perfringens isolation rate was 9.9% (43/435). The positive rate of tested farms was 29.6% (29/98). All the isolates were C. perfringens type A, only possessing the cpa gene encoding for toxin α. No netB gene encoding NetB toxin associated with necrotic enteritis, and no cpe gene encoding for the C. perfringens enterotoxin causing human intestinal disorder were detected. A quantitative PCR analysis revealed that the mean C. perfringens number in the intestinal contents was 3.9 × 10(6) colony-forming units (CFU)/g, ranging from 6.85 × 10(2) to 1.61 × 10(7) CFU/g. The gross and histopathologic lesions revealed a positive correlation (p < 0.05) between lesion score and C. perfringens number in the ilea of C. perfringens -positive chickens. Antimicrobial susceptibility tests of all C. perfringens isolates indicated that the minimum inhibitory concentration inhibiting 50% of isolates (MIC50) for amoxicillin, bacitracin, chlortetracycline, enrofloxacin, erythromycin, florfenicol, and lincomycin was ≤0.125, 0.5, 128, 0.25, ≥256, 2, and ≥256 μg/ml, respectively. Most of the C. perfringens isolates were susceptible to amoxicillin, bacitracin, and enrofloxacin but resistant to chlortetracycline, erythromycin, and lincomycin. Interestingly, C. perfringens isolated from chickens with severe lesions had higher MIC50 for erythromycin and lincomycin than those isolates from chickens with mild lesions. Conclusively, reductions in both the incidence of C. perfringens infection on farms and the concentrations of C. perfringens in intestines to improve broiler health are still needed in Taiwan.

Sequence diversity and associated pathogenicity of the hemagglutinin cleavage site of H5N2 avian influenza viruses isolated from chickens in Taiwan during 2013-2015

The sequence at the hemagglutinin (HA) cleavage site (CS) plays a key role in determining the pathogenicity of avian influenza viruses. Three types of HA CS sequences, QREKR/GL, QRKKR/GL and QRRKR/GL, were previously reported in Taiwanese H5N2 viruses that were isolated from chickens from 2003 to 2013. However, no HA CS sequence was reported for viruses isolated after 2013. This article presents the HA CS sequences and pathogenicity of H5N2 viruses that were isolated from chickens in Taiwan during 2013–2015. Two novel HA CS sequences, QKEKR/GL and KREKREKR/GL, were found in the viruses isolated in 2013 and 2014, and pathogenicity tests showed that the viruses with these novel HA CS sequences are low and high pathogenic viruses, respectively. In contrast, the HA CS sequence QREKR/GL was found in all viruses that were isolated in 2015, and all of these viruses were low pathogenic viruses. After 10 passages in embryonated chicken eggs, a virus strain that was isolated in 2003 evolved into a viral quasispecies that contained at least four distinct types of HA CS sequences. These results highlight the potential of Taiwanese H5N2 viruses to change their pathogenicity and HA CS sequences via mutations. Furthermore, viruses with the HA CS sequence QREKR/GL were more prevalent than others in 2015. These findings are useful for understanding the mechanism of sequence changes at the HA CS and for refining H5N2 virus control measures in Taiwan.

Relationship of bovine TNF-α gene polymorphisms with the risk of bovine tuberculosis in Holstein cattle

Many studies suggest significant genetic variation in the resistance of cattle and humans to infection with Mycobacterium bovis (M. bovis), the causative agent of zoonotic tuberculosis. TNF-α promotes inflammation and induces apoptosis in response to mycobacterial infection. The aim of the present study was to investigate the influence of single nucleotide polymorphisms of the TNF-α gene on bovine tuberculosis (bTB) susceptibility. We genotyped the TNF-α gene in 74 bTB-infected Holstein cows and 90 healthy control animals. The influence in the exon 3 region of TNF-α polymorphisms on bTB susceptibility was subsequently investigated by association analysis. Our finding demonstrated that the g.27534932A>C polymorphism of the TNF-α is associated with bTB in Holstein cattle. The susceptibility of cattle with the g.27534932A>C genotype compared with the CC genotype was 4.11-fold (95% CI, 1.27–13.36; P=0.02) higher. The g.27534932A>C polymorphism located in exon 3 of the TNF-α gene, and the functional consequence was missense. The deduced amino acid sequence for the protein product revealed an arginine to serine conversion at position 159, which may affect initiation of protein synthesis and disrupt normal TNF-α function that protects animals against mycobacterial infection. A significant association was observed with the A allele as a risk factor for bTB susceptibility (OR, 3.84; 95% CI, 1.21–12.17; P=0.02). In conclusion, this is the first report showing that the g.27534932A>C polymorphism may contribute to TNF-α-mediated bTB susceptibility.

Emergence of a sylvatic enzootic formosan ferret badger-associated rabies in Taiwan and the geographical separation of two phylogenetic groups of rabies viruses

Taiwan had been declared rabies-free in humans and domestic animals for five decades until July 2013, when surprisingly, three Formosan ferret badgers (FB) were diagnosed with rabies. Since then, a variety of wild carnivores and other wildlife species have been found dead, neurologically ill, or exhibiting aggressive behaviors around the island. To determine the affected animal species, geographic areas, and environments, animal bodies were examined for rabies by direct fluorescent antibody test (FAT). The viral genomes from the brains of selected rabid animals were sequenced for the phylogeny of rabies viruses (RABV). Out of a total of 1016 wild carnivores, 276/831 (33.2%) Formosan FBs were FAT positive, with occasional biting incidents in 1 dog and suspected spillover in 1 house shrew. All other animals tested, including dogs, cats, bats, mice, house shrews, and squirrels, were rabies-negative. The rabies was badger-associated and confined to nine counties/cities in sylvatic environments. Phylogeny of nucleoprotein and glycoprotein genes from 59 Formosan FB-associated RABV revealed them to be clustered in two distinct groups, TWI and TWII, consistent with the geographic segregation into western and eastern Taiwan provided by the Central Mountain Range and into northern rabies-free and central-southern rabies-affected regions by a river bisecting western Taiwan. The unique features of geographic and genetic segregation, sylvatic enzooticity, and FB-association of RABV suggest a logical strategy for the control of rabies in this nation.

In vitro gene expression profile of bovine peripheral blood mononuclear cells in early Mycobacterium bovis infection

The intracellular parasite Mycobacterium bovis (M. bovis) causes tuberculosis in cattle and humans. Understanding the interactions between M. bovis and host cells is essential in developing tools for the prevention, detection, and treatment of M. bovis infection. Gene expression profiles provide a large amount of information regarding the molecular mechanisms underlying these interactions. The present study analyzed changes in gene expression in bovine peripheral blood mononuclear cells (PBMCs) at 0, 4 and 24 h following exposure to M. bovis. Using bovine whole-genome microarrays, a total of 420 genes were identified that exhibited significant alterations in expression (≥2-fold). Significantly enriched genes were identified using the Kyoto Encyclopedia of Genes and Genomes database, of which the highest differentially expressed genes were associated with the immune system, signal transduction, endocytosis, cellular transport, inflammation, and apoptosis. Of the genes associated with the immune system, 84.85% displayed downregulation. These findings support the view that M. bovis inhibits signaling pathways of antimycobacterial host defense in bovine PBMCs. These in vitro data demonstrated that molecular alterations underlying the pathogenesis of tuberculosis begin early, during the initial 24 h following M. bovis infection.

Relationship of bovine NOS2 gene polymorphisms to the risk of bovine tuberculosis in Holstein cattle

Many studies suggest significant genetic variation in the resistance of cattle and humans to infection with Mycobacterium bovis, the causative agent of zoonotic tuberculosis. The inducible nitric oxide synthase (iNOS which is encoded by the NOS2 gene) plays a key role in the immunological control of a broad spectrum of infectious agents. This study aimed to investigate the influence of genetic variations in the promoter of the NOS2 gene on bovine tuberculosis (bTB) susceptibility. In this study, the NOS2 genes of 74 bTB-infected Holstein cows and 90 healthy controls were genotyped using PCR followed by nucleotide sequencing. Polymorphisms at rs207692718, rs109279434, rs209895548, rs385993919, rs433717754, rs383366213, rs466730386, rs715225976, rs525673647, rs720757654 and g.19958101T>G in the promoter region of the NOS2 gene were detected. The g.19958101T>G SNP produced two different conformation patterns (TT and TG) and the TG genotype was over-represented in the bTB group (20.27%) compared with the control group (2.22%). The TG genotype frequency of the g.19958101T>G variant was significantly higher in bTB cattle than in healthy controls (OR, 11.19; 95% CI, 2.47–50.73; P=0.0002). The G allele of the g.19958101T>G polymorphism was more frequent in bTB group when compared to control group (10.14% versus 1.11%). Furthermore, the G allele was a risk factor for bTB susceptibility (OR, 10.04; 95% CI, 2.26–44.65; P=0.0002). In conclusion, the g.19958101T>G polymorphism of the NOS2 gene may contribute to the susceptibility of Holstein cattle to bTB.

Molecular epidemiology of porcine reproductive and respiratory syndrome viruses isolated from 1991 to 2013 in Taiwan

Porcine reproductive and respiratory syndrome virus (PRRSV) was first identified in Taiwan in 1991, but the genetic diversity and evolution of PRRSV has not been thoroughly investigated over the past 20 years. The aim of this study was to bridge the gap in understanding of its molecular epidemiology. A total of 31 PRRSV strains were collected and sequenced. The sequences were aligned using the MUSCLE program, and phylogenetic analysis were performed by the maximum-likelihood method and the neighbor-joining method using MEGA 5.2 software. In the early 1990s, two prototype strains, WSV and MD001 of the North American genotype, were first identified. Over the years, both viruses evolved separately. The population dynamics of PRRSV revealed that the strains of the MD001 group were predominant in Taiwan. Evolution was manifested in changes in the nsp2 and ORF5 genes. In addition, a suspected newly invading exotic strain was recovered in 2013, suggesting that international spread is still taking place and that it is affecting the population dynamics. Overall, the results provide an important basis for vaccine development for the control and prevention of PRRS.

Influenza A plasma and serum virus antibody detection comparison in dogs using blocking enzyme-linked immunosorbent assay

Background and Aim:

The influenza A virus (IAV) is an important zoonotic pathogen with infections also reported in dogs. IAV infections can be detected through the presence of antibodies using the enzyme-linked immunosorbent assay (ELISA). Serum is the only standard sample source; however, there is no information on the availability of other sample sources for IAV antibody detection in dogs. Compared with serum, plasma is more widely employed in most animal hospitals. The object of this study is to investigate whether plasma collected in ethylenediaminetetraacetic acid (EDTA) tubes (EDTA plasma) or heparin tubes (heparin plasma) could be used in the ELISA protocol instead of serum for IAV antibody detection in dogs.

Materials and Methods:

Totally, 82 matched EDTA plasma and serum sample pairs and 79 matched heparin plasma and serum sample pairs were employed using blocking enzyme-linked immunosorbent assay (bELISA). The agreement and correlation between the plasma (EDTA or heparin plasma) and serum were assessed using the agreement index kappa (kD) calculation and Pearson correlation coefficient, respectively.

Results:

The agreement index kD of EDTA plasma and serum was 1.0, and that of heparin plasma and serum was 0.85. The Pearson correlation coefficient of EDTA plasma and serum was 0.87 (p<0.01), and that of heparin plasma and serum was 0.82 (p<0.01).

Conclusion:

The results proved that plasma, especially EDTA plasma, could be substituted for serum in the bELISA test. This might greatly expand the clinical applicability of IAV antibody detection in dogs.

Salmonella Enteritidis infection slows steroidogenesis and impedes cell growth in hen granulosa cells

Infection by Salmonella Enteritidis (SE) causes decreased egg production in laying hens. Immunoresponse, steroidogenesis, and cell proliferation by chicken granulosa cells (cGCs) are of particular interest because these changes are involved in follicular growth, atresia, and ovulation. To elucidate the possible mechanisms underlying these changes, transcriptional alterations in cGCs at distinct stages of follicular maturity were studied. Luteinizing hormone (LH)-and follicle-stimulating hormone (FSH) were applied to the cGCs isolated from hierarchical and prehierarchical follicles, respectively, to imitate the effects of gonadotropin during in vitro SE infection. Results showed that the expression of Toll-like receptor 15 was dependent on the follicular maturity, with mature cells having a more significant and progressively stronger immunoresponse. Attenuated responses to LH and FSH as well as retardant steroidogenesis due to down-regulated LH receptor, FSH receptor, and the P450 side-chain cleavage system were observed and may have led to delayed hierarchical follicular growth. Deteriorated cell viability of prehierarchical follicles may occur, as the proliferation of stimulator heparin-binding epidermal growth factor was reduced significantly. Furthermore, the infection led to a higher probability of cGCs from the smaller follicles undergoing apoptosis than those from F1 follicles. Collectively, the data provide evidence of a tendency toward pathogen elimination in F1 follicles by induction of a strong immune response and cell apoptosis in smaller follicles to avoid bacterial transovarian infection. It is our speculation that slowed steroidogenesis and impeded follicular growth may play essential roles in decreased ovulation rate as well as further decreased egg production during SE infection.

Efficacy of paced breathing for insomnia: enhances vagal activity and improves sleep quality

Fourteen self-reported insomniacs (SRI) and 14 good sleepers (GS) had their cardiac neuronal activity assessed by heart rate variability (HRV) under controlled respiration at a slow frequency rate of 0.1 Hz, and a forced rate of 0.2 Hz during daytime rest. Nighttime sleep was measured by polysomnography. The SRI showed depressed high frequency power of HRV compared to the GS. An increased total power of HRV was observed among the SRI during slow, paced breathing compared with spontaneous breathing and 0.2 Hz. Sleep onset latency, number of awakenings, and awakening time during sleep were decreased and sleep efficiency was increased if SRI practiced slow, paced breathing exercises for 20 min before going to sleep. Our results indicate that there is autonomic dysfunction among insomniacs, especially in relation to vagal activity; however, this decreased vagal activity can be facilitated by practicing slow, paced breathing, thereby improving sleep quality.

Relationships of bovine ephemeral fever epizootics to population immunity and virus variation

Bovine ephemeral fever is an arthropod-borne bovine viral disease caused by infection with bovine ephemeral fever virus which belongs to genus Ephemerovirus within the family Rhabdoviridae. In this study, serological data and virological information about the disease and the virus, spanning from 2001 to 2013, were employed to analyze the relationships of bovine ephemeral fever epizootics to population immunity and virus variation. National and regional surveillance data indicated that 2 of the 3 major epizootics and 87% regional outbreaks were associated with lower neutralizing antibody titers and immunity coverage, reflecting the importance of population immunity for the control of bovine ephemeral fever. Phylogenetic analysis and sequence comparison demonstrated that Taiwanese bovine ephemeral fever viruses were >96.0% and >97.6% similar to the East Asian isolates in nucleotide and amino acid sequences, respectively. These analyses supported that the Taiwanese viruses shared the same gene pool with the strains of the other East Asian countries, mainly Japan.

Avian hepatitis E virus in chickens, Taiwan, 2013

A previously unidentified strain of avian hepatitis E virus (aHEV) is now endemic among chickens in Taiwan. Analysis showed that the virus is 81.5%–86.5% similar to other aHEVs. In Taiwan, aHEV infection has been reported in chickens without aHEV exposure, suggesting transmission from asymptomatic cases or repeated introduction through an unknown common source(s).

Development of a multiplex Luminex assay for detecting swine antibodies to structural and nonstructural proteins of foot-and-mouth disease virus in Taiwan

BACKGROUND/PURPOSE(S)

Foot-and-mouth disease (FMD) and swine vesicular disease (SVD) are serious vesicular diseases that have devastated swine populations throughout the world. The aim of this study was to develop a multianalyte profiling (xMAP) Luminex assay for the differential detection of antibodies to the FMD virus of structural proteins (SP) and nonstructural proteins (NSP).

METHODS

After the xMAP was optimized, it detected antibodies to SP-VP1 and NSP-3ABC of the FMD virus in a single serum sample. These tests were also compared with 3ABC polypeptide blocking enzyme-linked immunosorbent assay (ELISA) and virus neutralization test (VNT) methods for the differential diagnosis and assessment of immune status, respectively.

RESULTS

To detect SP antibodies in 661 sera from infected naïve pigs and vaccinated pigs, the diagnostic sensitivity (DSn) and diagnostic specificity (DSp) of the xMAP were 90.0-98.7% and 93.0-96.5%, respectively. To detect NSP antibodies, the DSn was 90% and the DSp ranged from 93.3% to 99.1%. The xMAP can detect the immune response to SP and NSP as early as 4 days postinfection and 8 days postinfection, respectively. Furthermore, the SP and NSP antibodies in all 15 vaccinated but unprotected pigs were detected by xMAP. A comparison of SP and NSP antibodies detected in the sera of the infected samples indicated that the results from the xMAP had a high positive correlation with results from the VNT and a 3ABC polypeptide blocking ELISA assay. However, simultaneous quantitation detected that xMAP had no relationship with the VNT. Furthermore, the specificity was 93.3-94.9% with 3ABC polypeptide blocking ELISA for the FMDV-NSP antibody.

CONCLUSION

The results indicated that xMAP has the potential to detect antibodies to FMDV-SP-VP1 and NSP-3ABC and to distinguish FMDV-infected pigs from pigs infected with the swine vesicular disease virus.

First finding of Southeast Asia topotype of foot-and-mouth disease virus in Kinmen, Taiwan, in the 2012 outbreak

Foot-and-mouth disease virus, a member of genus Aphthovirus within the family Picornaviridae, affects cloven-hoofed animals, causing foot-and-mouth disease characterized by vesicle development. The Southeast Asia topotype, one of the topotypes within serotype O of the virus, is prevalent in some Asian countries, but had not previously been found in Taiwan. The topotype was first found in pigs in Kinmen Island, Taiwan, in 2012 and identified by nucleotide sequence comparison and phylogenetic analysis. Outbreaks were reported at 4 farms, resulting in the culling of 628 pigs and 1 cattle. Pigs were the only species infected during the outbreak. The incursion of Southeast Asia topotype into Taiwan implies the expansion of the topotype in East Asia.

A complete molecular diagnostic procedure for applications in surveillance and subtyping of avian influenza virus

INTRODUCTION

The following complete molecular diagnostic procedure we developed, based on real-time quantitative PCR and traditional PCR, is effective for avian influenza surveillance, virus subtyping, and viral genome sequencing.

METHOD

This study provides a specific and sensitive step-by-step procedure for efficient avian influenza identification of 16 hemagglutinin and 9 neuraminidase avian influenza subtypes.

RESULT AND CONCLUSION

This diagnostic procedure may prove exceedingly useful for virological and ecological advancements in global avian influenza research.

Notes from the field: wildlife rabies on an island free from canine rabies for 52 years--Taiwan, 2013

Dog-to-dog transmission of rabies in Taiwan was eliminated in 1961; the island was considered canine rabies-free for 52 years. On July 16, 2013, three ferret-badgers (Melogale moschata) tested positive for rabies by fluorescent antibody testing at the Animal Health Research Institute, Council of Agriculture of Taiwan. This was the first time wild animals other than bats were tested. During 1999-2012, a total of 6,841 clinically healthy dogs and five apparently normal cats from shelters were tested and found negative for rabies. During 2009-2012, a total of 322 bats were tested and found negative for rabies.

The application of a duplex reverse transcription real-time PCR for the surveillance of porcine reproductive and respiratory syndrome virus and porcine circovirus type 2

The porcine respiratory disease complex (PRDC) is the most common disease in commercial pork production worldwide. Porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV), the most important agents of PRDC, usually co-infect in the same pigs. In order to survey the prevalence of PCV2 and PRRSV in pigs of various ages, a duplex reverse transcription real-time PCR (DRT-rPCR) was developed and applied in the present study. The DRT-rPCR did not cross-react with 10 swine viruses other than PCV2 and PRRSV, with detection limits of 1 TCID50/ml for PCV2 and 6.3 TCID50/ml for PRRSV. Surveillance using DRT-rPCR together with serology revealed that in the five farms studied, pigs were most susceptible to PRRSV at 6-14 weeks of age, whereas susceptibility to PCV2 varied by the management system but was mostly at 10-14 weeks of age. Cross analysis of viral loads versus antibody titers revealed that PCV2 load was affected negatively by anti-PCV2 ORF2 antibody, which constituted the most important non-infectious factor affecting the development of PMWS. These results indicated that DRT-rPCR was developed and applied successfully to the surveillance of PCV2 and PRRSV in the field.

Comparison of primer sets and one-step reverse transcription polymerase chain reaction kits for the detection of bluetongue viral RNA

Bluetongue virus is the etiological agent of bluetongue, one of the most important insect-transmitted animal diseases in the world. To establish a feasible diagnostic procedure for detecting the viral RNA, seven commercially available one-step RT-PCR kits in combination with three primer sets were evaluated. Results of this study showed remarkable differences in analytical sensitivity between the examined RT-PCR kits. In addition, it was found that a World Organization for Animal Health-recommended primer set may not be effective in detecting most BTV RNA.

Rapid developing basaloid squamous cell carcinoma of the uterine cervix in a young adult Taiwanese

Basaloid squamous cell carcinoma (BSCC) of the uterine cervix is a rare malignancy of the female genital tract with a poorer clinical outcome than SCC of the uterine cervix. We report a case of BSCC of the uterine cervix developing rapidly in a young adult Taiwanese. A 35-year-old woman, Para 2, visited the emergency room with severe dizziness, palpitations and sudden excessive vaginal bleeding with hemoglobin of 3.6 g/dl. She had been well and healthy but intermittent vaginal spotting developed for around 6 months previously and was treated as abnormal uterine bleeding by ob-gyn practitioners. She had a repeat cesarean operation 16 months prior to this episode and the last Pap smear showed reactive change 12 months ago at our hospital. On examination, she had an ulcerated, necrotic, and punched-out lesion of 5 cm of the cervix. A cervical biopsy revealed poorly differentiated typical BSCC. Abdominal/pelvic computerized tomography and whole body positron emission tomography confirmed FIGO staging IB2. She responded well to concurrent chemoradiotherapy. Follow-up for the patient is ongoing. This is a rapid developing BSCC of the uterine cervix, although we cannot actually ascertain when it started and how rapidly it progressed.

Development of a Luminex assay for the detection of swine antibodies to non-structural proteins of foot-and-mouth disease virus

Foot-and mouth disease (FMD), swine vesicular disease (SVD), and vesicular stomatitis (VS) are highly contagious vesicular diseases of swine but are not easy to differentiate clinically. For the purpose of instant detecting of FMD and differentiating it from the other vesicular diseases, a Luminex assay was developed. Sera from 64 infected, 307 vaccinated, and 280 naïve pigs were tested by the Luminex assay. Diagnostic sensitivity of the assay was 100%. Diagnostic specificity of the assay was 98.7% in vaccinated pigs and 97.5% to 100% in naïve pigs. Agreement between the results from the Luminex assay and those from a 3ABC polypeptide blocking ELISA was 96.3% with kappa statistics of 0.92. The Luminex assay can detect the immune response to NSP-3ABC in swine as early as eight days post-infection. Moreover, all of the 15 vaccinated but unprotected pigs were all detected by the Luminex assay. The results indicated that the Luminex assay has potential with specificity in detecting antibodies to FMDV 3ABC NSP and in distinguishing FMDV-infected pigs from with either SVDV or VSV.

Pharmacokinetics and in vivo potency of soluble epoxide hydrolase inhibitors in cynomolgus monkeys

BACKGROUND AND PURPOSE

Soluble epoxide hydrolase inhibitors (sEHIs) possess anti-inflammatory, antiatherosclerotic, antihypertensive and analgesic properties. The pharmacokinetics (PK) and pharmacodynamics in terms of inhibitory potency of sEHIs were assessed in non-human primates (NHPs). Development of a sEHI for use in NHPs will facilitate investigations on the role of sEH in numerous chronic inflammatory conditions.

EXPERIMENTAL APPROACH

PK parameters of 11 sEHIs in cynomolgus monkeys were determined after oral dosing with 0.3 mg·kg(-1). Their physical properties and inhibitory potency in hepatic cytosol of cynomolgus monkeys were examined. Dose-dependent effects of the two inhibitors 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU) and the related acetyl piperidine derivative, 1-trifluoromethoxyphenyl-3-(1-acetylpiperidin-4-yl) urea (TPAU), on natural blood eicosanoids, were determined.

KEY RESULTS

Among the inhibitors tested, TPPU and two 4-(cyclohexyloxy) benzoic acid urea sEHIs displayed high plasma concentrations (>10 × IC(50)), when dosed orally at 0.3 mg·kg(-1). Although the 4-(cyclohexyloxy) benzoic acid ureas were more potent against monkey sEH than piperidyl ureas (TPAU and TPPU), the latter compounds showed higher plasma concentrations and more drug-like properties. The C(max) increased with dose from 0.3 to 3 mg·kg(-1) for TPPU and from 0.1 to 3 mg·kg(-1) for TPAU, although it was not linear over this range of doses. As an indication of target engagement, ratios of linoleate epoxides to diols increased with TPPU administration.

CONCLUSION AND IMPLICATIONS

Our data indicate that TPPU is suitable for investigating sEH biology and the role of epoxide-containing lipids in modulating inflammatory diseases in NHPs.

Functional impairment but not metabolic syndrome is associated with depression in older Taiwanese: results from the Social Environment and Biomarkers of Aging Study

OBJECTIVES

This study examined the association of metabolic syndrome, metabolic disorders and functional impairment with depression in older (≥54 years) adults.

DESIGN

A cross-sectional study.

SETTING

Data of this study were from the Social Environment and Biomarkers of Aging Study (SEBAS) in Taiwan (2000).

PARTICIPANTS

A national representative sample of persons 54 years of age or older in Taiwan (N = 1023).

RESULTS

Results showed that the presence of any number of metabolic disorders without functional impairment was not associated with depression. However, the presence of functional impairment regardless of the number of metabolic disorder was associated with a significantly higher risk of depression after adjusting for confounding factors (OR = 5.13, 95% CI = 2.13-12.36) (p<0.05). The presence of a basic Activities of Daily Living (ADL) dependency was significantly associated with a 1.45 times higher likelihood of depression (OR = 1.45, 95% CI = 1.17-1.79) (p<0.05).

CONCLUSIONS

Results suggest that functional impairment, but not metabolic syndrome or metabolic disorders, is associated with depression in older adults. Metabolic syndrome/disorders do not necessarily affect patient's psychological health unless it is accompanied with functional impairment.

Detection of florfenicol resistance genes in Riemerella anatipestifer isolated from ducks and geese

The cat gene, coding for chloramphenicol acetyltransferase has been reported for conferring the chloramphenicol resistance for Riemerella anatipestifer. Chloramphenicol acetyltransferases, however, are unable to inactivate florfenicol. In this study, 66 R. anatipestifer isolates were investigated for their susceptibility to chloramphenicol and florfenicol and the presence of floR gene. Results showed nine florfenicol intermediate or resistant R. anatipestifer isolates were all floR positive. The expression of floR gene in E. coli and inhibition studies with PAβN indicated that the floR gene was as an efflux pump conferring resistance to both chloramphenicol and florfenicol. Southern hybridization revealed the floR was located in the plasmid DNA of five isolates and in the chromosomal DNA of four isolates. Furthermore, two novel floR-carrying plasmids designated pRA0726 and pRA0846 were sequenced completely. pRA0726 was 11,704 bp in size with 10 putative open reading frames which included the floR, catB and bla(OXA-209) resistance genes. The most differences between sequences of pRA0846 and pRA0726 were the absence of a bla(OXA-209) gene and the deletion of 321 nucleotides of orf1 in pRA0846. Plasmid curing tests demonstrated that pRA0726 carried functional coding proteins for resistance to phenicol and β-lactam antimicrobials. To the best of our knowledge, this is the first report of presence of the floR and bla(OXA-209) resistance genes in R. anatipestifer.

Differentiation of foot-and-mouth disease-infected pigs from vaccinated pigs using antibody-detecting sandwich ELISA

The presence of serum antibodies for nonstructural proteins of the foot-and-mouth disease virus (FMDV) can differentiate FMDV-infected animals from vaccinated animals. In this study, a sandwich ELISA was developed for rapid detection of the foot-and-mouth disease (FMD) antibodies; it was based on an Escherichia coli-expressed, highly conserved region of the 3ABC nonstructural protein of the FMDV O/TW/99 strain and a monoclonal antibody derived from the expressed protein. The diagnostic sensitivity of the assay was 98.4%, and the diagnostic specificity was 100% for naïve and vaccinated pigs; the detection ability of the assay was comparable those of the PrioCHECK and UBI kits. There was 97.5, 93.4 and 66.6% agreement between the results obtained from our ELISA and those obtained from the PrioCHECK, UBI and CHEKIT kits, respectively. The kappa statistics were 0.95, 0.87 and 0.37, respectively. Moreover, antibodies for nonstructural proteins of the serotypes A, C, Asia 1, SAT 1, SAT 2 and SAT 3 were also detected in bovine sera. Furthermore, the absence of cross-reactions generated by different antibody titers against the swine vesicular disease virus and vesicular stomatitis virus (VSV) was also highlighted in this assay's specificity.

Prevalence and molecular characterization of chloramphenicol resistance in Riemerella anatipestifer isolated from ducks and geese in Taiwan

Riemerella anatipestifer is a Gram-negative bacterium that can cause disease in a wide range of wild and domesticated birds, especially waterfowl. The presence of an antibiotic-resistance gene in R. anatipestifer has not yet been reported, indicating the need for investigation. In the present study, 40.5% of R. anatipestifer isolates were found to exhibit resistance to chloramphenicol, while 45.9% showed intermediate resistance and 13.5% were susceptible to chloramphenicol, an antibiotic that has been prohibited for use in food animals in Taiwan since 2003. The resistance gene was identified as the cat gene and cloned by library sequencing. The prevalence of the cat gene in Taiwanese R. anatipestifer isolates was 78.4%. The position of the cat gene was then determined within the novel plasmid, designated pRA0511. pRA0511 was sequenced and shown to be 11,435 bp in size with 10 open reading frames (ORFs). Proteins putatively encoded by these 10 ORFs included four drug-resistance-associated proteins. Two proteins designed as chloramphenicol acetyltransferases (CATs) were encoded by two non-adjacent ORFs, and the other two were TetX2 and a multi-drug ABC transporter permease/ATPase. The putative CAT protein had 62.9 to 79.5% homology to a known type B CAT. The pRA0511 plasmid is the first identified drug-resistance plasmid in R. anatipestifer, more specifically associated with chloramphenicol resistance.

The association of age, gender, body fatness and lifestyle factors with plasma C-reactive protein concentrations in older Taiwanese

OBJECTIVE

This study determined the population distribution of plasma C-reactive protein (CRP) and evaluated its association with age, body fatness status and lifestyle factors in elderly Taiwanese.

DESIGN

A crosssectional-study.

SETTING

A population-representative sample. The "1999-2000 Elderly Nutrition and Health Survey in Taiwan".

PARTICIPANTS

2432 non-institutionalized population-representative Taiwanese, 65 y or older.

MEASUREMENTS

Plasma CRP-concentrations and factors that impact plasma CRP concentrations.

RESULTS

Results showed that weighting-adjusted plasma CRP concentration (mean +/- SE) was 2.50 +/- 0.10 mg/L for men and 2.70 +/- 0.10 mg/L for women. Cigarette smoking was positively associated with plasma CRP concentrations in both men and women. Age was positively (P < 0.05) but physical activity was negatively (P <0.05) associated with plasma CRP concentrations in men. These associations were not significant in women. Waist circumference but not BMI was significantly (P < 0.05) associated with plasma CRP in women. Both associations were not significant in men. Alcohol drinking and betel nut-chewing were not significantly associated with CRP concentrations.

CONCLUSION

Results suggest that there are gender-related differences in the degree of association of CRP concentrations with age, waist circumference, BMI and physical activity in older Taiwanese. Results also suggest population-related differences in the strength of many associations when compared to observations made in Western countries. These findings may help delineate the differences in cardiovascular risk among various populations.

Use of random amplified polymorphic DNA analysis and single-enzyme amplified fragment length polymorphism in molecular typing of Ornithobacterium rhinotracheale strains

Ornithobacterium rhinotracheale (ORT) is a bacterium common to commercial poultry and wild birds throughout the world. It is also known as a causative agent of respiratory diseases. A total of 93 ORT isolates originating from chickens, pigeons, ostriches, quail, turkeys, and an Asian crested goshawk (Accipiter trivirgatus) in Taiwan, between 2004 and 2006, were used in this study. High genetic similarity (97%-100%) in 16S rRNA sequence was revealed among the 50 randomly selected isolates, in addition to a reference strain (ATCC-51464) and seven reference sequences from GenBank. In order to obtain a greater genetic discrimination among the ORT isolates, random amplified polymorphic DNA (RAPD) and single-enzyme amplified fragment length polymorphism (SE-AFLP) methods were further conducted. The results showed that both RAPD and SE-AFLP assays showed higher discriminatory abilities than the 16S rRNA sequence assay. Genetic clustering revealed that chicken- and quail-origin isolates were genetically distinct from those of the ostrich, pigeon, and Asian crested goshawk-origin isolates. However, among the two typing methods, the turkey-origin isolates showed diverse genetic characteristics to domestic avian species. With this information, ecologic and epidemiologic studies could be furthered for the reduction and control of ORT transmission in Taiwan.

Swollen head syndrome in Taiwan-isolation of an avian pneumovirus and serological survey

Outbreaks of swollen head syndrome (SHS) were observed in two broiler and two broiler-breeder farms in Taiwan. The disease was characterized by oedematous swelling of the head, especially surrounding the eyelids, the neck and wattles. Avian pneumovirus and Escherichia coli were isolated from birds in all four farms. In addition, Staphylococcus aureus and infectious bursal disease virus were each isolated from one farm. A serological survey of 398 birds from 11 broiler breeder farms showed 86.4% (344) of them had ELISA antibodies against turkey rhinotracheitis virus.

Sequence analysis of a duck picornavirus isolate indicates that it together with porcine enterovirus type 8 and simian picornavirus type 2 should be assigned to a new picornavirus genus

In a 1990 outbreak, a virus isolated in Taiwan from the intestines of ducks showing signs of hepatitis was tentatively classified as a picornavirus on the basis of physical, chemical, and morphological characteristics. The virus was cloned and then found not to be type 1 duck hepatitis virus (DHV-1) or a new serotype of duck hepatitis virus (N-DHV) by serum neutralization. Complete genome sequencing indicated that the virus genome had 8351 nucleotides and the typical picornavirus genome organization (i.e., 5' untranslated region (UTR)-L-P1 (VP 4-2-3-1)-P2 (2A-B-C)-P3 (3A-B-C-D)-3' UTR-poly A). One open reading frame encoded 2521 amino acids, which makes this virus one of the largest picornaviruses, second only to equine rhinitis B virus of the genus Erbovirus. Its L protein was the largest within the family Picornaviridae (451 amino acids) and suspected to be a trypsin-like protease. The 235-nucleotide 3' UTR region was of intermediate size, quite long compared to other picornaviruses but shorter than other picornaviruses of duck-origin (DHV-1 and N-DHV) and had four regions of secondary structure. The 2A protein was composed of only 12 amino acids, which is the shortest of any member of the family Picornaviridae. Phylogenetic analysis of the polyprotein and 3D sequences indicated that this virus (named duck picornavirus [DPV]) together with porcine enterovirus type 8 virus and several simian picornaviruses form a distinct branch of the family Picornaviridae and should be assigned to a new picornavirus genus.

Phylogenetic characterization of Newcastle disease viruses isolated in Taiwan during 2003–2006

Isolates of Newcastle disease virus (NDV) from chicken cases were obtained from various locations in Taiwan during 2003-2006 and were genotypically analyzed by using reverse transcription polymerase chain reaction (RT-PCR) with primers specific to the viral fusion (F) protein gene (534 bp). Part of the amplified F protein DNA product (nucleotide sequence 47-418) and the deduced amino acid sequences were compared phylogenetically with those from strains previously reported in Taiwan and other geographic regions. Our results showed that all Taiwanese isolates (n=20) collected during 2003-2006, according to the phylogenetic tree, belong to the genotype VIId. In addition, all the six Taiwanese isolates obtained in 2003, carry the motif (112)R-R-Q-K-R(116) and have the amino acid L(23) replaced by F(23) (assigned as Group 1). On the other hand, 12 out of the 14 Taiwanese isolates obtained during 2004-2006 possess the motif (112)R-R-K-K-R(116) and have the amino acid G(74), instead of E(74) (assigned as Group 2). To our best knowledge, this is the first reported VIId isolates that possess the sequences of G(74)/(112)R-R-K-K-R(116) within the F0 protein. Since a high mortality, severe clinical signs, typical postmortem lesions, and a high intra-cerebral pathogenicity index (ICPI) were observed in the NDV-infected chickens, these isolates acquired between 2003 and 2006 are considered as the velogenic type. The Group 2 viruses have become dominant and responsible for the majority of Taiwanese outbreaks during recent years. Based on our phylogenetic analysis, it can be postulated that these isolates were evolved from previously reported local strains, and the Group 2 family emerged the latest in the genotype VIId. The information is fundamental to improving the efficiency of controlling strategies and vaccine development for NDV.

Quadruple-bend achromatic low emittance lattice studies

A quadruple-bend achromatic (QBA) cell, defined as a supercell made of two double-bend cells with different outer and inner dipole bend angles, is found to provide a factor of 2 in lowering the beam emittance relative to the more conventional double-bend achromat. The ratio of bending angles of the inner dipoles to that of the outer dipoles is numerically found to be about 1.5-1.6 for an optimal low beam emittance in the isomagnetic condition. The QBA lattice provides an advantage over the double-bend achromat or the double-bend nonachromat in performance by providing a small natural beam emittance and some zero-dispersion straight sections. A lattice with 12 QBA cells and a preliminary dynamic aperture study serves as an example.

Phenotypic and molecular characterization of isolates of Ornithobacterium rhinotracheale from chickens and pigeons in Taiwan

Forty Ornithobacterium rhinotracheale (ORT) strains were isolated from 28 chickens and 12 pigeons for the first time in Taiwan. All isolates reacted positively in the p-nitrophenyl-beta-D-galactopyranoside (PNPG) and oxidase tests, showing an API 20NE identification system biocode 0-0-2-0-0-0-4. All the pigeon isolates and 85.7% (24 of 28) of the chicken isolates belonged to serotype A. Compared to the ORT ATCC 51464 strain, 14.3% (4 of 28) of chicken isolates and 58.3% (7 of 12) of pigeon isolates showed smaller colonies after 72 hr incubation. Most of the chicken isolates (22 of 28), but none of the pigeon isolates, could agglutinate chicken and pigeon red blood cells. There appears to be a correlation that ORT isolates with a larger colony size tend to be more able to agglutinate red blood cells than the ORT isolates with a smaller colony size. A majority of isolates was sensitive to amoxicillin, ampicillin, ceftiofur, penicillin, and oxytetracycline. The 16S ribosomal RNA (rRNA) sequences of 23 Taiwanese ORT isolates showed high identity (98%-100%) to sequences in GenBank. Phylogenetic analysis of these sequences showed that pigeon isolates formed a distinctive cluster, while chicken isolates and all other 16S rRNA sequences obtained from GenBank belonged to another two clusters. The results indicate that pigeon ORT isolates are different from most chicken isolates in regard to a number of phenotypic and molecular traits.

Molecular characterization of a new serotype of duck hepatitis virus

Duck hepatitis strains 90D and 04G were determined to be antigenically unrelated to type 1 duck hepatitis virus (DHV-1) by in vitro cross-neutralization assay. The genome sequences of 90D and 04G revealed that both strains of the new serotype DHV (N-DHV) possessed a typical picornavirus genome organization apart from the unique possession of three in-tandem 2A genes present in DHV-1. The 2A1, 2A2, and 2A3 proteins represented an aphthovirus-like 2A protein, AIG1-like protein, and human parechovirus-like 2A protein, respectively. The N-DHV genome displayed unique features, compared to the DHV-1 genome. The 366 nt 3'UTR of N-DHV, the largest determined thus far among picornaviruses, was 52 nt longer than DHV-1. The pairwise percent identity of the nucleic acid and amino acid sequences at 1D region of N-DHV and DHV-1 were only 69.1-69.7 and 70.1-70.5%, respectively. Finally, phylogenetic and evolutionary analysis of N-DHV revealed that the N-DHV and DHV-1 belong to two different clusters of a novel genus in the Picornaviridae family.

Molecular analysis of duck hepatitis virus type 1 indicates that it should be assigned to a new genus

The genome sequences of three duck hepatitis virus type 1 (DHV-1) strains were determined. Comparative sequence analyses showed that they possessed a typical picornavirus genome organization apart from the unique possession of three in-tandem 2A genes. The 2A1 protein of DHV-1 is an aphthovirus-like 2A protein; the 2A2 protein is not related to any known picornavirus protein; the 2A3 protein is a human parechovirus-like 2A protein. Several other features were found to be unique to the DHV-1 genome when compared with other picornaviruses: (i) the 3' UTR of DHV-1 was composed of 314 nt, the largest among the picornaviruses; (ii) pair-wise amino acid sequence identities between polyprotein of DHV-1 and other picornaviruses are all less than 30%. The pair-wise amino acid sequence identities in the 3D region of DHV-1 with LV and HPeV-1 is only 38.6 and 36.6%, respectively, and less than 30% with all other picornaviruses; (iii) the DHV-1 capsid polypeptide VP0 is not proteolytically cleaved into VP4 and VP2; and (iv) phylogenetic and evolutionary analysis of DHV-1 reveals a new picornavirus clade. It is therefore proposed that DHV-1 should be assigned to a new genus in the Picornaviridae.

PCR-based restriction fragment length polymorphism (RFLP) analysis of Campylobacter jejuni isolates from humans, chickens and dogs in northern Taiwan

Two hundred and twenty strains of Campylobacter jejuni (70 human, 51 canine and 99 chicken strains) were isolated from September 2003 to September 2004 in northern Taiwan. These strains were subtyped by PCR-RFLP analysis of the flagellin (FlaA) gene. On the basis of restrictive digest, six types were identified with AfaI, seven types with MboI and five types with HaeIII. With the combination of these three enzymes, 47 distinct PCR-RFLP patterns were observed-25 each from human and chicken isolates, and 9 from canine isolates. In human strains, the most frequently occurring types were Cj-28 (14.3%), Cj-17 (10%), Cj-16 (8.6%), Cj-37 (7.1%) and Cj-46 (7.1%). In canine strains, the most prevalent types were Cj-1 (33.3%), Cj-26 (19.6%), Cj-3 (15.7%), Cj-2 (9.8%) and Cj-10 (9.8%). In chicken strains, the most frequently occurring types were Cj-46 (40.4%), Cj-29 (9.1%), Cj-45 (7.1%) and Cj-41 (5.1%). The results suggest that poultry is a source, but not the sole source, of C. jejuni infection in humans. Two RFLP types, Cj-17 and Cj-37, frequently occurring in human isolates in this study have also been found to be prevalent in human isolates in Japan, China and the Czech Republic, indicating a possible international clonal spread.

Resistance of Immune-Suppressed Pigeons to Subtypes H5N2 and H6N1 Low Pathogenic Avian Influenza Virus

Resistance to infection with avian influenza virus (AIV) was studied in healthy and immune-suppressed pigeons, which were treated with the immunosuppressant cyclophosphamide (Cy) before infection. Two subtypes of low pathogenic AIV (LPAIV; CK/TW/H5 and CK/TW/H6) were inoculated via the oculonasal route. Nested reverse transcriptase-polymerase chain reaction (nested RT-PCR) and virus isolation were used as detection methods. The Cy-treated and -untreated pigeons in both experiments did not shed viruses or become antibody positive throughout the 21-day observation period. All pigeons were negative for AIV RNA when trachea, lung, pancreas, spleen, kidney, and rectum tissues were examined. Negative results were also obtained in uninoculated contact chickens, which were housed together with H6N1 AIV-inoculated pigeons. Therefore, it was concluded that the pigeons are resistant to infection with these two LPAIVs and do not serve as transmission hosts, even in the presence of immune dysfunction.

Serological survey of racing pigeons for selected pathogens in Taiwan

To investigate the pathogens that racing pigeons in Taiwan are exposed to, a total of 3764 pigeons from 90 lofts were analysed by collection of blood samples in the period between October 2000 and September 2001. The haemagglutination inhibition (HI) test was performed to detect antibodies against Newcastle disease virus (NDV), type 2 avian paramyxovirus (APMV-2), and egg drop syndrome '76 virus (EDS-76V). The agar-gel precipitin (AGP) test was used to detect antibodies against fowl adenovirus (FAV), goose parvovirus (GPV), and avian reovirus (REO). The virus neutralisation (VN) test was applied to detect antibodies against the serotypes FAV-1 and FAV-8. A rapid serum agglutination test was applied for the detection of antibodies against Mycoplasma spp. Antibodies to several infectious agents were found, including NDV (43.3%), EDS-76V (19.2%), FAV (0.8%), REO (0.5%), APMV-2 (0.2%), Mycoplasma columbinum (10.3%), M. columborale (7.1%), M. synoviae (1.8%) and M. gallisepticum (1.3%). Antibodies against GPV, FAV-1, and FAV-8 were not detected in any serum sample. NDV seroprevalence was significantly higher in pigeons of more than one year of age than in pigeons younger than one year. ND or EDS-76 seroprevalence of pigeons vaccinated with ND vaccine or EDS-76 vaccine was significantly higher than that of pigeons that did not receive any vaccination.

Trout Ea4- or human Eb-peptide of pro-IGF-I disrupts heart, red blood cell, and vasculature development in zebrafish embryos

E-peptide of the pro-insulin-like growth factor (pro-IGF)-I is produced by proteolytic cleavage of the pro-hormone in post-translational processing. Introduction of a transgene encoding a secreted form of rtEa4- or hEb-peptide into newly fertilized zebrafish (Danio rerio) eggs by electroporation or microinjection resulted in embryos with abnormal cardiovascular features and reduced red blood cells and vasculature. Two different phenocopies of heart developmental defects were observed: (i) Group I embryos exhibited heart development arrested at the heart muscle stage and (ii) group II embryos exhibited heart development arrested at the heart tube stage. Both groups of embryos also exhibited reduction of red blood cells and vasculature. The mRNA levels of genes essential for heart development (GATA 5 and NKX2.5), hematopoiesis (GATA 1 and GATA 2), and vasculogenesis (VEGF) in normal and defective embryos were determined by quantitative real-time RT-PCR at 36 hr post-fertilization (hpf). Significant reduction of GATA 5, NKX2.5, GATA 1, GATA 2, and VEGF mRNA levels was observed in both groups of defective embryos. These results suggest that overexpression of rtEa4 or hEb transgene in zebrafish embryos disrupts heart development, hematopoiesis, and vasculogenesis by reducing the levels of GATA 5, NKX2.5, GATA 1, GATA 2, and VEGF mRNA.

Immunohistochemical Study of Lymph Nodes in Patients with Cat Scratch Disease

BACKGROUND/PURPOSE

Bartonella henselaeis the causative agent of cat scratch disease (CSD), manifesting as fever and acute regional lymphadenopathy. Although serologic testing is the reference method for diagnosis, successful use of immunohistochemical (IHC) stain of regional lymph nodes for the diagnosis of CSD has been reported. To determine the characterization and diagnostic potential of IHC in lymphadenopathy of CSD, lymph nodes were excised from patients with suspected CSD for further evaluation.

METHODS

Polyclonal antibody-based IHC studies were performed for the detection of B. henselae. Between January 2001 and December 2004, the reference laboratory of the Center for Disease Control, Taiwan, received a total of 377 sera from 352 reported suspected CSD cases. Twenty-three formalin-fixed paraffin-embedded lymph nodes from 16 patients and two skin biopsies from two patients suspected of having CSD were included in this study. Nine of them were serologically confirmed to have CSD and the others were seronegative but suspected to have CSD by the attending physicians. Seven lymph node specimens were obtained from tuberculosis patients for comparison.

RESULTS

We demonstrated that the microorganisms existed in the cytoplasm of histiocytes within the granulomatous lesions in nine lymph nodes and one skin biopsy. Among the nine lymph nodes with IHC (+) stains, three were seronegative. On the other hand, three cases were IHC (+) and six cases were IHC (-) among nine seronegative patients. In addition, two seronegative patients with skin biopsy showed one IHC (+) and one IHC (-).

CONCLUSION

IHC can contribute to the etiologic diagnosis of B. henselaelymphadenopathy when serology and molecular techniques are not available.