Min-Liang Wong - Academia.edu (original) (raw)

Papers by Min-Liang Wong

Virus Genes, 2002

The pseudorabies virus (PRV) immediate-early regulatory protein IE180 is able to transactivate th... more The pseudorabies virus (PRV) immediate-early regulatory protein IE180 is able to transactivate the viral early and late genes. Using chloramphenicol acetyltransferase (CAT) assay, we investigated the transactivation function of IE180 to the promoter of PRV glycoprotein X (gX) gene, and our results showed that IE180 could significantly increase the expression of CAT gene which was under the control of gX

Journal of Veterinary Medical Science, 2015

Orf virus (ORFV), a member of parapoxvirus, is an enveloped virus with genome of double-stranded ... more Orf virus (ORFV), a member of parapoxvirus, is an enveloped virus with genome of double-stranded DNA. ORFV causes contagious pustular dermatitis or contagious ecthyma in sheep and goats worldwide. In general, detection of viral DNA and observing ORFV virion in tissues of afflicted animals are two methods commonly used for diagnosis of orf infection; however, isolation of the ORFV in cell culture using virus-containing tissue as inoculum is known to be difficult. In this work, the ORFV (Hoping strain) isolated in central Taiwan was successfully grown in cell culture. We further examined the biochemical characteristic of our isolate, including viral genotyping, viral mRNA and protein expression. By electron microscopy, one unique form of viral particle from ORFV infected cellular lysate was demonstrated in the negative-stained field. Moreover, immunomodulating and anti-influenza virus properties of this ORFV were investigated. ORFV stimulated human monocytes (THP-1) secreting proinflammatory cytokines IL-8 and TNF-α. And, pre-treatment of ORFV-infected cell medium prevents A549 cells from subsequent type A influenza virus (IAV) infection. Similarly, mice infected with ORFV via both intramuscular and subcutaneous routes at two days prior to IAV infection significantly decreased the replication of IAV. In summary, the results of a current study indicated our Hoping strain harbors the immune modulator property; with such a bio-adjuvanticity, we further proved that pre-exposure of ORFV protects animals from subsequent IAV infection.

BMC veterinary research, Jan 27, 2014

Neutrophil gelatinase-associated lipocalin (NGAL) is a useful biomarker for the early prediction ... more Neutrophil gelatinase-associated lipocalin (NGAL) is a useful biomarker for the early prediction of renal diseases. NGAL may exist as monomer, dimer and/or NGAL/MMP-9 complex forms in humans. In this study, the existence of various forms of NGAL in urine (uNGAL) was determined and whether these forms are related to the different urinary diseases found in dogs is further discussed. Eighty-one urine samples from dogs with different forms of renal disease (41), pyuria (19) and a number of non-renal related diseases (10), as well as healthy dogs (11), were collected. uNGAL concentrations and their molecular forms in dogs were measured by ELISA and Western blot analysis, respectively. The uNGAL concentrations of dogs with pyuria (median: 15.35 ng/mL) were significantly higher than those of the healthy control animals (median: 3.92 ng/mL) (p < 0.01), but lower than those of dogs with renal diseases (median: 23.77 ng/mL). Each NGAL molecular form could be detected in dog urine. In parti...

The Veterinary Journal, 2010

Germline mutations in the BRCA2 tumour suppressor gene are significant risk indicators of breast ... more Germline mutations in the BRCA2 tumour suppressor gene are significant risk indicators of breast cancer in women, especially for hereditary breast cancer. The BRCA2 protein interacts via the BRC (breast cancer) domain with RAD51, an essential component of the cellular machinery for the maintenance of genome stability and double strand-breaks repair. Exon 11 is the largest exon of the BRCA2 gene and contains the region encoding eight repeats of the BRC domain. Little is known about the roles of BRCA2 exon 11 in canine mammary tumours. In present study, the entire BRCA2 exon 11 was sequenced in canine mammary tumours. Fifteen mammary gland samples were obtained from four normal mammary glands and 11 mammary tumours (10 malignant and one benign tumours). Comparing sequences of normal mammary glands with those in GenBank (AB043895 and Z75664), a single nucleotide polymorphism (SNP) at codon 2414 G > A (resulting in a lysine to an arginine substitution) was identified. When compared with the normal mammary gland, 19 sporadically distributed point mutations were found in mammary tumours, including 68% of missense and 32% of silent mutations. A high frequency of genetic variations in codon 511 A > C or 2414 A > G were identified in 6/11 cases, and two missense mutations (2414 A > G, 2383 A > C) were located at the fourth repeat of the BRC domains.

Virus Genes, 2005

Canine parvovirus (CPV) is a non-enveloped virus with a single-stranded DNA genome and causes inf... more Canine parvovirus (CPV) is a non-enveloped virus with a single-stranded DNA genome and causes infectious enteritis in dog. In this study, 36 isolates of CPV infection were obtained in Taichung, Taiwan from 2003 to 2004. Using primers that can distinguish subtypes of CPV, we amplified part of viral VP2 gene by polymerase chain reaction (PCR) and the PCR product was sequenced; results demonstrated that two isolates could be classified as type 2a of CPV and the others were type 2b. The complete coding region of VP2 gene of type 2b was also sequenced, and phylogenetic analysis of these DNA sequences revealed that our Taichung isolate was close to the V-120, FPV-314, 97-008, Taiwan 9, LCPV-T1, and T4 isolates; however, because of the degeneracy of codons, the amino acid sequences of Taichung isolate was similar to that of the 97-008 isolate from Japan. It is known that two important amino acid residues (Asn-426 in type 2a and Asp-426 in type 2b; Ile-555 in type 2a and Val-555 in type 2b) are the determinants for the discrimination of type 2a or type 2b. After scrutinizing the complete VP2 gene of our Taichung isolate, we found the VP2 protein of the Taichung isolate did possess this molecular feature of type 2b virus. Previous studies reported that type 2a virus was the major type in Taiwan; our finding showed that CPV type 2b was the predominant type in the middle part of Taiwan. Moreover, a unique Ala-489 in VP2 of our Taichung isolate was found, contrasting to a Val-489 in the VP2 of other strains.

PLoS ONE, 2013

Curcumin, a natural compound and ingredient in curry, has antiinflammatory, antioxidant, and anti... more Curcumin, a natural compound and ingredient in curry, has antiinflammatory, antioxidant, and anticarcinogenic properties. Previously, we reported that curcumin abrogated influenza virus infectivity by inhibiting hemagglutination (HA) activity. This study demonstrates a novel mechanism by which curcumin inhibits the infectivity of enveloped viruses. In all analyzed enveloped viruses, including the influenza virus, curcumin inhibited plaque formation. In contrast, the nonenveloped enterovirus 71 remained unaffected by curcumin treatment. We evaluated the effects of curcumin on the membrane structure using fluorescent dye (sulforhodamine B; SRB)-containing liposomes that mimic the viral envelope. Curcumin treatment induced the leakage of SRB from these liposomes and the addition of the influenza virus reduced the leakage, indicating that curcumin disrupts the integrity of the membranes of viral envelopes and of liposomes. When testing liposomes of various diameters, we detected higher levels of SRB leakage from the smaller-sized liposomes than from the larger liposomes. Interestingly, the curcumin concentration required to reduce plaque formation was lower for the influenza virus (approximately 100 nm in diameter) than for the pseudorabies virus (approximately 180 nm) and the vaccinia virus (roughly 335 6 200 6 200 nm). These data provide insights on the molecular antiviral mechanisms of curcumin and its potential use as an antiviral agent for enveloped viruses.

Journal of Virological Methods, 2005

Using the upstream region of glycoprotein E gene of pseudorabies virus (PRV) as a model, a method... more Using the upstream region of glycoprotein E gene of pseudorabies virus (PRV) as a model, a method based on reverse transcriptasepolymerase chain reaction (RT-PCR) for the determination of transcriptional start site was developed. The conventional primer extension method was used to determine the start site. Comparing the results obtained by these two methods, a good agreement on the location of start site was achieved. In addition, a computer program was used to predict the transcriptional start site, and the predicted site was found to be close to the two sites obtained by experiments. Based on the transcriptional start site data and on the general knowledge of the eukaryotic gene, the TATA box of gE gene was assigned at ∼33 bp upstream to the start site.

Journal of Virological Methods, 2009

A loop-mediated isothermal amplification (LAMP) assay using six primers targeting a highly conser... more A loop-mediated isothermal amplification (LAMP) assay using six primers targeting a highly conserved region of the B2L gene has been developed to diagnose orf virus. The assay produces a ladder-like pattern of products on an agarose gel that can be specifically digested with BsrGI enzyme. The sensitivity of the LAMP assay, which was determined to be a single copy of the standard plasmid, was 100 fold and 10 fold higher than PCR and nested PCR, respectively; furthermore, no cross-reactivity was founded with the other tested viruses. By staining the products directly in the tube with PicoGreen or ethidium bromide, the products can be visualized with a similar sensitivity as by gel electrophoresis. Clinical samples were tested using PCR, nested PCR and LAMP assay and the positive rates were 60%, 70% and 70%, respectively. The LAMP assay allows easy, rapid, accurate and sensitive detection of infection with orf virus and is especially applicable in a resource-limited situation.

Journal of Veterinary Medical Science, 2004

Journal of Veterinary Medical Science, 2007

This report concerns a case of pancreatic carcinoma with widespread metastases to many organs inc... more This report concerns a case of pancreatic carcinoma with widespread metastases to many organs including intracranial metastasis. An eleven-year-old, male, mixed-breed dog showed emaciation, ataxia, and multiple visible tumors within the neck. A MRI examination of the patient was conducted because of ataxia, and it was found that the intracranial invasive growth had resulted in compression of the brain stem. Necropsy was performed after the patient died. Based on gross and microscopic examination, the primary tumor cells were located in the left lobe of the pancreas and widespread metastasis was found into various organs, including the brain, lungs, liver, kidneys, tonsils, serosal surface of the esophagus, and submandibular, pulmonary hilar, mediastinal, and mesenteric lymph nodes. This case indicates that pancreatic adenocarcinoma should be included in the differential diagnosis list when cervical neck masses are detected.

Journal of Veterinary Diagnostic Investigation, 2014

The A32L gene from a Goatpox virus (GTPV) strain isolated from a goat in Yunlin County (Taiwan) d... more The A32L gene from a Goatpox virus (GTPV) strain isolated from a goat in Yunlin County (Taiwan) displays several substitutions compared with the sequence of the Kenyan GTPV vaccine strain SGP0240 and the Pellor GTPV strain. Samples from the skin lesions on 6 goats with GTPV infection or from goats with Orf virus (ORFV) infection were tested in a multiplex polymerase chain reaction (PCR) system that used primers GPF, GPR1, and GPR2 as well as previously published primers specific for ORFV. These primers were able to amplify either GTPV or ORFV without cross-reactivity. A high-resolution melt analysis (HRMA) was carried out on amplified DNA from the skin lesions of 6 goats with GTPV infection and with the GTPV SGP0240 strain. The results indicated that the melting temperature profiles amplified from samples with Yunlin GTPV infection can be differentiated from the GTPV SGP0240 strain. The findings showed that a successful differential assay for these GTPVs had been developed. Accordin...

Journal of the American Veterinary Medical Association, 2005

Objective—To identify prognostic factors for female dogs that have undergone surgical removal of ... more Objective—To identify prognostic factors for female dogs that have undergone surgical removal of malignant mammary tumors. Design—Retrospective case series. Animals—79 female dogs with malignant mammary tumors. Procedure—Information obtained from the medical records included breed, age, sex, tumor size (maximum diameter), number and location of affected mammary glands, time between tumor identification and surgical removal, radiographic evidence of distant metastasis, surgical procedure, ovariohysterectomy (OHE) status, histologic classification of the tumor, and survival time. Results—Results of univariate analyses indicated that clinical stage, tumor size, OHE status, metastasis to adjacent lymph nodes or distant sites, and histologic classification of the tumor were significantly associated with survival 2 years after surgery. Tumors ≥ 5 cm in diameter and tumors that had been identified > 6 months before surgery were more likely to metastasize to adjacent lymph nodes. Ovarioh...

Journal of the American Veterinary Medical Association, 2009

Objective—To evaluate the prognostic potential of expression of hormone receptors in malignant ma... more Objective—To evaluate the prognostic potential of expression of hormone receptors in malignant mammary gland tumors of dogs. Design—Cohort study. Animals—89 female dogs with malignant mammary gland tumors and 24 female dogs with benign mammary gland tumors. Procedures—Female dogs with malignant (n = 89 dogs) and benign (24) mammary gland tumors were evaluated to determine the prognostic value of the expression of estrogen receptor (ER)A or the progesterone receptor (PR), as determined by use of immunohistochemical methods. Results—In this study, 68 (60.2%) and 88 (77.9%) of the 113 dogs with mammary gland tumors had expression of ERA and PR, respectively. Expression of ERA and PR was detected proportionately more frequently in benign tumors (23/24 [95.8%] and 24/24 [100%], respectively) than in malignant tumors (45/89 [50.6%] and 64/89 [71.9%]). Percentage of tumors with positive results for ERA and PR was significantly higher in tumors < 5 cm in diameter; as clinical stage I, II...

Journal of Clinical Microbiology, 2010

Mouse mammary tumor virus (MMTV) has been speculated to be involved in human breast cancer. Compa... more Mouse mammary tumor virus (MMTV) has been speculated to be involved in human breast cancer. Companion animals, dogs, and cats with intimate human contacts may contribute to the transmission of MMTV between mouse and human. The aim of this study was to detect MMTV-like nucleotide sequences in canine and feline mammary tumors by nested PCR. Results showed that the presence of MMTV-like env and LTR sequences in canine malignant mammary tumors was 3.49% (3/86) and 18.60% (16/86), respectively. For feline malignant mammary tumors, the presence of both env and LTR sequences was found to be 22.22% (2/9). Nevertheless, the MMTV-like LTR and env sequences also were detected in normal mammary glands of dogs and cats. In comparisons of the MMTV-like DNA sequences of our findings to those of NIH 3T3 (MMTV-positive murine cell line) and human breast cancer cells, the sequence similarities ranged from 94 to 98%. Phylogenetic analysis revealed that intermixing among sequences identified from tissu...

Journal of Aquatic Animal Health, 2007

The aims of this study were to purify and localize the nitric oxide synthases (NOSs) from hybrid ... more The aims of this study were to purify and localize the nitric oxide synthases (NOSs) from hybrid tilapia (Nile tilapia Oreochromis niloticus × Mozambique tilapia O. mossambicus). The purification procedures involved affinity chromatography with a 2′, 5′‐ADP‐agarose 4B column and ion exchange with a diethylaminoethanol Bio‐Gel A column. The results from gel filtration assays showed that the molecular weights of neuronal NOS (nNOS) and inducible NOS (iNOS) were 178 and 120 kDa, respectively. The sodium dodecyl sulfate–polyacrylamide gel electrophoresis results showed that there were three bands with molecular weights of 89, 47, and 29 kDa from the purified nNOS. However, only one band, with a molecular weight of 120 kDa, appeared on the gel from the purified iNOS. Hybrid tilapia nNOS was a dimer structure, while iNOS appeared to be a monomer structure. Moreover, our results revealed that the activities of nNOS and iNOS were significantly higher after the addition of Ca+2 or Mg+2 ions ...

Gene, 2009

Two outbreaks of orf virus (a parapoxvirus) infection in goats found in Nantou and Taiping of cen... more Two outbreaks of orf virus (a parapoxvirus) infection in goats found in Nantou and Taiping of central Taiwan were investigated. The nucleotide and the amino acid sequences of viral B2L, E3L and A32L genes in these two outbreaks were analyzed, and each of their phylogenetic trees were also constructed. In the A32L gene, an unexpected deletion of 24 nucleotides was found in the Taiping strain. The A32L gene can encode an ATPase and is supposed to be involved in virion DNA packaging. The 24 nucleotides correspond to 8 amino acids residues of the viral ATPase, which are located near the C-terminal region of the enzyme. Moreover, two copies of the RGD sequence at C-terminal region of ATPase were found in the Nantou strain. The 24nucleotide difference in the A32L gene indicated that the Nantou strain and the Taiping strain were two separate strains, and it can be used in differential molecular diagnosis. Moreover, the C-terminal heterogeneity was found to be a general feature of the viral ATPase. Lastly, similar functional motifs of the ATPase and the Ras proto-oncoprotein (a GTPase) are discussed.

Archives of Virology, 1997

Previous results from our laboratory have demonstrated that type I DNA topoisomerase activity is ... more Previous results from our laboratory have demonstrated that type I DNA topoisomerase activity is required for the replication and gene expression of pseudorabies virus (PRV). In the present report, we further analyzed the expression of topoisomerase I in PRV-infected cells, and the western blot result showed that the expression of topoisomerase I was increased after virus infection. The increase sustained to late time of infection when the cytopathic effect was obvious and the synthesis of most host proteins was shut off by PRV. From transient expression assay, it was also found that the promoter of cellular topoisomerase I gene could be stimulated by immediate-early protein (IE180) and viral early protein 0 (EP0), and these two regulatory proteins appeared to work synergistically. Collectively, these ®ndings provide evidence that PRV can stimulate the expression of topoisomerase I and that the stimulation is mediated at least by IE180 and EP0 proteins of PRV at the transcriptional level. * DNA topoisomerases are enzymes that modulate the topological structure of DNA, and their participation in the biological process of DNA replication, transcription and recombination have been well established (reviewed in [6, 23]). The essential roles of topoisomerase I and/or II in the life cycle of several herpesviruses, such as herpes simplex virus (HSV), cytomegalovirus (CMV) and Epstein-Barr virus (EBV), have also been reported [3, 7, 14]. Using camptothecin, a topoisomerase I inhibitor, we have recently shown that type I topoisomerase activity is essential for the replication and gene expression of PRV in cell culture [26]. Like other members of alphaherpesviruses, the gene expression of PRV in productive infection is tightly controlled in a cascade mode and can be divided into immediate-early, early and late genes according to the kinetics of

Nature, 2012

Reallocate funds to boost performance Last month's report by the Council of Canadian Academies, p... more Reallocate funds to boost performance Last month's report by the Council of Canadian Academies, prepared at the government's request, reveals that Canada's research output and impact rank seventh and sixth in the world, respectively (see go.nature.com/ pyvwlk). Shouldn't the country be performing better, given its sustained investment in research and development (R&D)? Gross domestic expenditure on R&D by the government and higher-education sectors was 0.77% of gross domestic product (GDP) in 2008 and has been maintained throughout the global financial crisis (0.79% in 2010). Although Canada performs well given its small population, its GDP is relatively high because of natural-resource exports, so these figures may be underestimates. Its 2008 R&D investments exceeded those of Japan and of every European Union member except Finland and France (see go.nature. com/59dg8f). Canadian academia can improve returns on this public investment. Stimulating competition and responsibility for delivering research output and impact would support the government's commitment to fiscal accountability. For example, it could assess researchers every 5-10 years and reallocate a small amount of existing public funding to the highest performers. These measures could bring Canada in line with other developed countries, such as the United Kingdom and Australia.