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T L Lin

Publications and source records attributed to T L Lin.

At least 37 records · Page 2Linked to original sources
PubMed2001

Fibronectin attachment protein homologue mediates fibronectin binding by Mycobacterium avium subsp. paratuberculosis.

Attachment of Mycobacterium avium subsp. paratuberculosis to host tissue and penetration of mucosal surfaces are pivotal events in the pathogenesis of Johne's disease. Fibronectin (FN) binding is required for attachment and internalization of several mycobacteria by epithelial cells in vitro. The objective of this study was to further characterize the FN binding activity of M. avium subsp. paratuberculosis. Although the bacteria bound FN poorly at pH above 7, brief acid pretreatment greatly enhanced FN binding within the pH range (3 to 10) studied. A 4.6-kbp fragment from an M. avium subsp. paratuberculosis genomic library was found to contain a 1,107-bp open reading frame that shows very high nucleotide sequence identity with that of the FN attachment protein (FAP) gene of M. avium subsp. avium. Pretreatment of FN with an FN-binding peptide from M. avium subsp. avium FAP abolished FN binding, indicating that M. avium subsp. paratuberculosis binds FN in a FAP-dependent manner. Pretreatment of M. avium subsp. paratuberculosis with anti-FAP immunoglobulin G did not abrogate FN binding; blocking occurred only when anti-FAP was added together with FN. FAP was detected by immunofluorescence only in lipid-extracted M. avium subsp. paratuberculosis. Western blotting and immunoelectron microscopy revealed that FAP is located near the interior of the cell envelope of M. avium subsp. paratuberculosis. The results indicate that a FAP homologue mediates the attachment of FN to M. avium subsp. paratuberculosis. Further, given the subcellular location of FAP, it is considered that this protein operates at the terminus of a coordinated FN binding system in the cell envelope of M. avium subsp. paratuberculosis.

Adhesins, Bacterial↗
PubMed2001

Subtyping HIV-1 infections in Taiwan using peptide-enzyme immunoassay, reverse transcription-polymerase chain reaction, and sequencing.

BACKGROUND AND PURPOSE: There are important questions about epidemiologic transmission patterns as well as the possibility that genetic and phenotypic differences in human immunodeficiency virus type 1 (HIV-1) affect transmissibility, infectivity, pathogenicity, and response to therapy and vaccines. To delinate the genetic heterogeneity of HIV-1 and the association of subtypes with risk factors and location of residence in Taiwan, subtypes of HIV-1 in Taiwanese patients were identified and a phylogenetic study was performed. In addition, the accuracy of peptide-enzyme immunoassay (EIA) using serum samples from Taiwanese patients infected with HIV-1 was investigated. METHODS: Peptide-EIA was used to give a preliminary subtype of HIV-1-positive serum samples collected from different areas of Taiwan. Reverse transcription (RT)-polymerase chain reaction (PCR) and genetic sequencing were used to confirm the peptide-EIA results and to construct a phylogenetic tree. RESULTS: Among the 149 serum samples, 98 were subtype B (66%), 38 subtype E (25%), two subtype Thai-B (1.3%), one subtype G (0.7%), and one subtype C (0.7%). Comparison of risk factors for HIV-1 infection and subtype revealed that most B subtype infections (59/98) occurred in homosexual or heterosexual patients, whereas 28 of 38 E subtype infections occurred in heterosexual patients. The B/E ratio was significantly different (p < 0.05) in Taipei than in other areas of Taiwan. CONCLUSIONS: These results suggest that the predominant subtype of HIV-1 infection in Taiwan is B, followed by E, and that the distribution of HIV-1 subtypes in Taiwan is similar to that of Thailand, although the genetic sequences are distinct. Homosexuality, heterosexuality, bisexuality, and intravenous drug use behaviors affect the distribution of different subtypes of HIV-1 infection. Peptide-EIA in conjunction with RT-PCR and sequencing can provide accurate subtyping of HIV-1 infection.

Acquired Immunodeficiency Syndrome↗
PubMed2001

Nucleocapsid protein gene sequence analysis reveals close genomic relationship between turkey coronavirus and avian infectious bronchitis virus.

Antibodies to infectious bronchitis virus (IBV) cross-react with turkey coronavirus (TCV) in immunofluorescence assay (IFA) indicating that IBV and TCV may share an amino acid sequence similarity. To determine its extent, the gene encoding the nucleocapsid (N) protein of TCV was amplified by reverse transcription-PCR (RT-PCR) from RNA purified from intestines of embryos of turkeys infected with various TCV isolates and from allantoic fluid of chicken embryos infected with IBV M41 strain, the obtained N genes were cloned, sequenced and compared with known sequences of N genes of five IBV strains. The primers for amplification were designed from the genome of IBV PCR products were obtained only from two of eight TCV isolates tested. It was found that the two TCV isolates were identical with five IBV strains by 90.1-94.1% at the N gene level. It was also observed that the N gene of eight TCV isolates originating from various regions of the USA could not be amplified by the primers designed from the N gene of bovine coronavirus (BCV).

Amino Acid Sequence↗
PubMed2000

Antimicrobial susceptibility of Mycoplasma hyorhinis.

A broth microdilution technique was used to determine the antimicrobial susceptibility of 15 field isolates of Mycoplasma hyorhinis to 10 antimicrobial agents, representative of different classes, and contrasting newer agents to existing ones. For the macrolides, the MIC(90) for tylosin and tilmicosin was 1 and 4 microg/ml, respectively, but was > or = 16 microg/ml for erythromycin. Tetracycline, lincomycin and enrofloxacin each had an MIC(90) of 2 microg/ml. The mycoplasma had similar levels of susceptibility to the aminoglycoside and aminocyclictol classes exhibiting an MIC(90) of 4 microg/ml for gentamicin and 2 microg/ml for spectinomycin. The isolates exhibited high MICs to trimethoprim/sulfamethoxazole with an MIC(90) > or = 16/304 microg/ml. In summary, M. hyorhinis isolates from the US had low MICs against a variety of antimicrobials tested, with the exception of erythromycin and trimethoprim/sulfamethoxazole.

Animals↗
PubMed2000

Association of a T29-->C polymorphism of the transforming growth factor-beta1 gene with genetic susceptibility to myocardial infarction in Japanese.

BACKGROUND: Transforming growth factor-beta (TGF-beta) is an important regulator of vascular remodeling and is involved in the pathogenesis of atherosclerosis. A T-->C transition at nucleotide 29 of the TGF-beta1 gene results in a Leu-->Pro substitution at amino acid 10 of the signal peptide. We have now examined a possible association of TGF-beta1 genotype with myocardial infarction (MI) in a Japanese population. METHODS AND RESULTS: TGF-beta1 genotype was determined in 315 Japanese patients (234 men and 81 women) with MI and 591 control subjects (289 men and 302 women). We found that age, body mass index, and incidence of habitual smoking, hypertension, diabetes mellitus, and hypercholesterolemia did not differ between the 2 groups for either men or women. Multivariable logistic regression analysis, however, demonstrated the frequency of the T allele to be significantly higher in male subjects with MI than in controls (TT + TC versus CC; P<0.0001, odds ratio 3.5, 95% CI 2.0 to 6.3). In contrast, the T allele was not associated with the prevalence of MI in women. In both male MI patients and controls, the serum concentration of TGF-beta1 was significantly higher in individuals with the CC genotype than in subjects with the TT or TC genotype. CONCLUSIONS: Findings suggest that the T allele at nucleotide 29 in the TGF-beta1 gene is a risk factor for genetic susceptibility to MI, at least in middle-aged Japanese men.

Aged↗
PubMed2000

Effect of ascorbic acid supplementation on the immune response of chickens vaccinated and challenged with infectious bursal disease virus.

One-day-old chickens were divided into two groups and reared under similar conditions. One group was fed a diet supplemented with 1000ppm ascorbic acid and the other group was fed an identical diet, but not supplemented with ascorbic acid. Both groups were vaccinated against infectious bursal disease (IBD) at 7 days of age and challenged orally with 4x10(5) of 50% embryo-lethal-dose IBDV 14 days later. The number of anti-IBDV antibody secreting cells, production of interleukin-2 (IL-2) by splenocytes, number of CD4(+), CD8(+) and IgM(+) cells in spleen and IgM(+) cells in bursa of Fabricius were compared between the two groups at 7 days (prior to vaccination), 21 days (14 days post-vaccination and prior to challenge) and 31 days (10 days post-challenge) of age. The number of CD8(+) in spleen at 7 days of age and IgM(+) cells in bursa at 7, 21 and 31 days of age were significantly higher in ascorbic acid supplemented group (P<0.05). Production of IL-2 by splenocytes was higher as indicated by higher stimulation indices in ascorbic acid supplemented group. The number of anti-IBDV IgG antibody secreting cells in spleen at 21 and 31 days of age were significantly higher in ascorbic acid supplemented group (P<0.05). Dietary supplementation of ascorbic acid may ameliorate the immunosuppression caused by IBDV vaccination and improve humoral and cellular immune responses.

Animals↗
PubMed2000

Molecular basis for the polymerization of octopus lens S-crystallin.

S-Crystallin from octopus lens has a tertiary structure similar to sigma-class glutathione transferase (GST). However, after isolation from the lenses, S-crystallin was found to aggregate more easily than sigma-GST. In vitro experiments showed that the lens S-crystallin can be polymerized and finally denatured at increasing concentration of urea or guanidinium chloride (GdmCl). In the intermediate concentrations of urea or GdmCl, the polymerized form of S-crystallin is aggregated, as manifested by the increase in light scattering and precipitation of the protein. There is a delay time for the initiation of polymerization. Both the delay time and rate of polymerization depend on the protein concentration. The native protein showed a maximum fluorescence emission spectrum at 341 nm. The GdmCl-denatured protein exhibited two fluorescence maxima at 310 nm and 358 nm, respectively, whereas the urea-denatured protein showed a fluorescence peak at 358 nm with a small peak at 310 nm. The fluorescence intensity was quenched. Monomers, dimers, trimers, and polymers of the native protein were observed by negative-stain electron microscopic analysis. The aggregated form, however, showed irregular structure. The aggregate was solubilized in high concentrations of urea or GdmCl. The redissolved denatured protein showed an identical fluorescence spectrum to the protein solution that was directly denatured with high concentrations of urea or GdmCl. The denatured protein was readily refolded to its native state by diluting with buffer solution. The fluorescence spectrum of the renatured protein solution was similar to that of the native form. The phase diagrams for the S-crystallin in urea and GdmCl were constructed. Both salt concentration and pH value of the solution affect the polymerization rate, suggesting the participation of ionic interactions in the polymerization. Comparison of the molecular models of the S-crystallin and sigma-GST suggests that an extra ion-pair between Asp-101 and Arg-14 in S-crystallin contributes to stabilizing the protomer. Furthermore, the molecular surface of S-crystallin has a protruding Lys-208 on one side and a complementary patch of aspartate residues (Asp-90, Asp-94, Asp-101, Asp-102, Asp-179, and Asp-180) on the other side. We propose a molecular model for the S-crystallin polymer in vivo, which involves side-by-side associations of Lys-208 from one protomer and the aspartate patch from another protomer that allows the formation of a polymeric structure spontaneously into a liquid crystal structure in the lens.

Animals↗
PubMed2000

Ascorbic acid supplementation improved antibody response to infectious bursal disease vaccination in chickens.

The purpose of the present study was to determine if supplementation of ascorbic acid (AA) to the diet would have a beneficial effect on infectious bursal disease (IBD) vaccination of chickens for protection against infectious bursal disease virus (IBDV) infection. Two hundred forty specific pathogen-free (SPF) chickens were divided into eight experimental groups. A 2 x 2 x 2 factorial arrangement in a completely randomized design was used; AA supplementation at 1,000 ppm in the diet, vaccination, and challenge were the main effects. Prior to challenge and 10 d after challenge, serum AA concentration, serum corticosterone concentration, ELISA antibody titer to IBDV, body weight, bursa-to-body weight (B:B) ratio, and bursal histological score (BHS) were determined. Nonvaccinated chickens fed a diet supplemented with AA did not exhibit clinical signs or mortality following challenge, whereas AA-unsupplemented counterparts had 100% cumulative morbidity and 30% cumulative mortality. Serum AA levels of AA-supplemented and vaccinated chickens were significantly (P < 0.05) higher than AA-unsupplemented and vaccinated chickens. Fourteen days following vaccination, significantly (P < 0.05) higher ELISA titers to IBDV were observed in vaccinated chickens supplemented with AA as compared to AA-unsupplemented counterparts. Ascorbic acid-supplemented chickens, especially those also vaccinated, had higher body weight gains as compared to the AA-unsupplemented chickens. Ascorbic acid-supplemented chickens challenged with IBDV did not show any clinical signs or mortality. The results suggest that supplementation of AA at 1,000 ppm in the diet has beneficial effects on antibody response to IBD vaccination and body weight gain.

Animals↗
PubMed2000

Immunoglobulin D multiple myeloma.

BACKGROUND: Immunoglobulin D (IgD) multiple myeloma (MM) is rare, accounting for less than 2% of all patients with MM in Western countries. In Taiwan, the frequency and clinicopathologic features of IgD MM have not yet been reported. METHODS: The clinicopathologic features and treatment outcome of patients with IgD MM diagnosed between January 1, 1982, and December 31, 1998, in Chang Gung Memorial Hospital were retrospectively reviewed. Nineteen patients with IgD MM were diagnosed. Of those patients, the medical records of 16 were available for review. RESULTS: Most of the patients were male (11/16) with a median age of 59 years. The most common presenting features included bone pain (56%), gastrointestinal discomfort (38%), general malaise (38%), and body weight loss (25%). The majority of patients had cytopenia (88%), renal function impairment (75%), hypercalcemia (63%), hyperuricemia (69%), elevated beta 2-microglobulin levels (86%), and Bence Jones proteinuria (92%). Serum protein electrophoresis showed an M-peak in 9 cases (9/12), whereas immunoelectrophoresis or immunofixation identified an IgD monoclonal gammopathy in all 16 patients. All of the M-proteins were of a lambda-light chain type. The IgD level ranged between 584 and 129,000 IU/ml (normal, < 100 IU/ml). All the patients had stage III disease except one (stage I). Four patients were still alive at the time of this analysis. The median survival time was 12 months. Infection was the leading cause of death (50%). CONCLUSION: The present series showed that IgD MM had aggressive clinical features, male predominance, a high frequency of renal function impairment, high incidence of M-protein undetected by serum protein electrophoresis, a predilection for lambda-light chains, and a short period of survival.

Adult↗
PubMed1999

Immune response of neonatal specific pathogen-free cats to experimental infection with Bartonella henselae.

The purpose of this study was to determine whether neonatal cats develop and maintain a persistent bacteremia for longer than do adult cats with a normal mature immune system, and whether neonatal cats are susceptible to infection with Bartonella henselae by oral inoculation. Neonatal specific pathogen-free (SPF) cats were inoculated with B. henselae intradermally (n = 4) or orally (n = 5) or with 0.9% NaCl (n = 2). Blood was collected periodically through 16 weeks post-inoculation (PI) for serology, bacteriology and complete blood count. Cats inoculated orally or intradermally at 3-5 days of age were bacteremic through 12-16 weeks PI, similar to what is documented for adult cats inoculated intradermally or intravenously. One cat inoculated at age 2 weeks was bacteremic through 10 weeks PI; the other was not bacteremic. Intradermally inoculated neonatal cats produced serum IgG antibodies to B. henselae but orally inoculated neonatal cats did not. Infected cats with and without serum IgG antibodies to B. henselae became blood-culture negative simultaneously, suggesting that IgG is not required to clear bacteremia.

Animals↗
PubMed1999

The gene for an abundant parasite coat protein predicts tandemly repetitive metal binding domains.

Immobilization antigens are highly abundant surface membrane proteins that coat the surface of hymenostomatid ciliates. While their function is unknown, recent studies with the common fish parasite, Ichthyophthirius multifiliis, suggest their involvement in a novel mechanism of humoral immunity involving an effect of antibody on parasite behavior. To gain further insight into the nature of these proteins, we have cloned a gene encoding the 48kDa i-antigen of I. multifiliis. Analysis of the gene (designated IAG48[G1]) reveals a single, uninterrupted reading frame that predicts a protein of 442 amino acids. Based on its deduced amino acid sequence, the protein contains hydrophobic amino acid domains at its N- and C-terminus that are characteristic of signal peptide and GPI-anchor addition sites, respectively. The most striking feature of the predicted protein, however, is a series of tandem repeats that spans most of its length. The repeats themselves are characterized by periodic cysteine residues that fall into register when the homologous segments are aligned. Interestingly, the spacing of cysteines (C-X2,3-C) within a framework of larger (C-X2-C-X20-C-X3-C-X20-C-X2-C) motifs is entirely consistent with the structure of known zinc-binding proteins. Finally, comparison of the coding sequence of the 48kDa i-antigen gene with a partial cDNA previously thought to encode this protein reveals nearly complete identity except at their 3' ends, suggesting that alternative forms of the antigen exist.

Amino Acid Sequence↗
PubMed1999

Amplification and cloning of infectious bursal disease virus genomic RNA segments by long and accurate PCR.

Improved methods of reverse transcription, polymerase chain reaction (PCR) amplification, and cloning of full-length coding region of both strands of infectious bursal disease virus (IBDV) variant strain E genome were developed. Denaturation of IBDV RNA by heat in the presence of primers and use of a reverse transcriptase lacking RNase-H activity produced full-length coding region and partial non-coding region cDNA copies of the viral genomic segments. Digestion of the RNA component of RNA-cDNA hybrids by RNase-H followed by long and accurate PCR (LA-PCR) amplification of IBDV cDNA in a single step resulted in the synthesis of 3182 base-pairs (bp) of segment A and 2777 bp of segment B cDNA copies of IBDV genome. The resulting amplicons were successfully cloned and sequenced revealing their identity of IBDV. The LA-PCR method can be utilized for the amplification and cloning of the other IBDV strains or isolates and will greatly enhance the availability of sequence information or infectious cDNA copies of IBDV.

Animals↗
PubMed1999

Spontaneous resolution of internal jugular vein thrombosis in a Salmonella neck abscess patient.

This article describes a rare case of Salmonella neck abscess complicated by internal jugular vein thrombosis in a 51-year-old patient with previously undiagnosed diabetes. The patient was discharged without any complications after a combination of medical and surgical treatment. Also discussed here are the clinical manifestations, imaging findings, and spontaneous resolution of the internal jugular vein thrombosis. Being immunocompromised is a critical predisposing factor for Salmonella neck abscess. Patient recovery is largely determined by proper incision, drainage of pus and adequate intravenous antibiotics according to bacterial sensitivity tests. Detection of an internal jugular vein thrombosis does not signify a poor prognosis. Spontaneous resolution of thrombosis is encountered after treating the infection.

Abscess↗
PubMed1999

Dynamics of nontypical apoptotic morphological changes visualized by green fluorescent protein in living cells with infectious pancreatic necrosis virus infection.

Morphologically, apoptotic cells are characterized by highly condensed membrane blebbing and formation of apoptotic bodies. Recently, we reported that apoptosis precedes necrosis in a fish cell line infected with infectious pancreatic necrosis virus (IPNV). In the present study, we tested the possibility that nontypical apoptosis is a component of IPNV-induced fish cell death. A variant type of green fluorescent protein (EGFP) was expressed in a fish cell line such that EGFP served as a protein marker for visualizing dynamic apoptotic cell morphological changes and for tracing membrane integrity changes during IPNV infection. Direct morphological changes were visualized by fluorescence microscopy by EGFP in living cells infected with IPNV. The nontypical apoptotic morphological change stage occurred during the pre-late stage (6 to 7 h postinfection). Nontypical apoptotic features, including highly condensed membrane blebbing, occurred during the middle apoptotic stage. At the pre-late apoptotic stage, membrane vesicles quickly formed, blebbed, and were finally pinched off from the cell membrane. At the same time, at this pre-late apoptotic stage, apoptotic cells formed unique small holes in their membranes that ranged from 0.39 to 0.78 micrometer according to examination by scanning electron microscopy and immunoelectron microscopy. Quantitation of the intra- and extracellular release of EGFP by CHSE-214-EGFP cells after IPNV infection was done by Western blotting and fluorometry. Membrane integrity was quickly lost during the late apoptotic stage (after 8 h postinfection), and morphological change and membrane integrity loss could be prevented and blocked by treatment with apoptosis inhibitors such as cycloheximide, genistein, and EDTA before IPNV infection. Together, these findings show the apoptotic features at the onset of pathology in host cells (early and middle apoptotic stages), followed secondarily by nontypical apoptosis (pre-late apoptotic stage) and then by postapoptotic necrosis (late apoptotic stage), of a fish cell line. Our results demonstrate that nontypical apoptosis is a component of IPNV-induced fish cell death.

Animals↗
PubMed1999

The epidemiology of Japanese encephalitis on Taiwan during 1966-1997.

Japanese encephalitis (JE) is an endemic disease in Taiwan. A mass vaccination program of children against JE was first implemented in 1968. Along with general improvements in various aspects of living conditions over the years, the program has brought JE well under control. The main characteristics of JE epidemiology in Taiwan in the past 3 decades are as follows. The transmission mode remains unchanged-that is, the amplification stage of the virus in pigs is followed by a human epidemic each year. The frequency of JE incidence has dropped significantly. The incidence rate of confirmed cases was 2.05 per 100,000 in 1967, the highest in record, and merely 0.03 per 100,000 in 1997. Confirmed cases occur sporadically all over the island. The peak of the epidemic season has shifted from August in the 1960s to June since the 1980s. The age distribution of confirmed cases has shifted gradually from mainly children to adults. Vaccine efficacy for those having received more than 2 doses of the vaccine is estimated to be about 85%.

Adult↗
PubMed1999

A ribozyme targeted to RNA polymerase gene of infectious bursal disease virus effectively cleaves and inhibits expression of the viral gene product.

Five hammerhead-type ribozymes were designed and cloned to cleave infectious bursal disease virus (IBDV) RNA and inhibit protein synthesis from cloned full-length viral cDNA genes. Two ribozymes (R1 and R2) were directed to the large viral RNA segment gene and three ribozymes (R3, R4, and R5) were directed to the small viral RNA segment gene. Targets for the ribozymes were produced from cloned full-length coding regions of both small and large viral RNA segment genes. Ribozymes and their corresponding targets were synthesized as in vitro transcripts. Despite several attempts at different temperatures, no cleavage of viral RNA transcripts with four of the ribozymes (R1, R2, R3, and R5) was observed. One of the ribozymes, R4, was effective in cleaving the viral RNA polymerase gene transcripts in a magnesium-dependent manner. Ribozyme R4 caused 82% reduction in the synthesis of the viral RNA polymerase gene product. The inhibition was specific since there was no change in the rate of synthesis of the Escherichia coli beta-galactosidase protein. The results suggest that ribozyme R4 can be used as potential anti-IBDV agent. It was also demonstrated that the hammerhead-type ribozymes can cleave sites other than conventional GUC sequence motif as the cleavage site of ribozyme R4 had GUU motif which conformed to the NUX consensus motif.

Animals↗