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Purbiantoro W, Huynh-Phuoc V, Castillo-Corea BRJ, Byadgi OV, Cheng TC. Effectiveness of dietary heat-killed Bacillus subtilis harboring plasmid containing 60 copies of CpG-ODN 1668 against Vibrio harveyi in Penaeus vannamei. Vet Res Commun 2024; 48:85-101. [PMID: 37530963 DOI: 10.1007/s11259-023-10182-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Accepted: 07/20/2023] [Indexed: 08/03/2023]
Abstract
The cost of the purification process hinders the extensive use of cytosine phosphate guanosine-oligodeoxynucleotides (CpG-ODNs) for shrimp culture. Therefore, this study used a shuttle vector plasmid to carry 60 copies of CpG-ODN 1668 (pAD43-25_60CpG), which can replicate in Escherichia coli and Bacillus subtilis strain RIK1285. The first experiment used a reverse gavage procedure to deliver a substance (PBS [CK], pAD43-25 [P0], and pAD43-25_60CpG [P60], respectively) directly into the anterior midgut of Penaeus vannamei and transcriptome sequence analysis with a reference genome was performed to examine the expression of well-known immune-related genes. The results showed that the expression levels of immune-related genes in P60 group were significantly increased, particularly those associated with AMPs. In addition, using RT‒qPCR, the expression levels of AMP genes (LvALF, LvPEN-2, and LvPEN-3) in the P60 group may vary depending on the tissue and time point. The second experiment used dietary supplementation with three kinds of heat-killed B. subtilis (HKBS, HKBS-P0, and HKBS-P60) in 28 days of feeding experiments. The results showed that dietary supplementation with HKBS-P60 did not significantly improve shrimp growth performance and survival. However, on days 14 and 28 of the feeding regimens, alkaline phosphatase (AKP) and acid phosphatase (ACP) activity were considerably higher than in other treatments. In addition, following infection with Vibrio harveyi, AKP and ACP activity in the HKBS-P60 group was significantly higher than in other treatments, particularly at the early stage of bacterial infection. Moreover, HKBS-P60 was found to be better protected against V. harveyi infection with lower cumulative mortality (60%) compared to HKBS (90%) and HKBS-P0 (100%) at 7 days after infection. Overall, these findings confirmed that P60 could increase immunological responses in the shrimp midgut, and HKBS-P60 could be used as an effective tool to enhance the immune response and disease resistance in shrimp.
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Affiliation(s)
- Wahyu Purbiantoro
- Laboratory of Molecular Fish Immunology and Genetics, Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Research Center for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Research Center for Marine and Land Bioindustry, National Research and Innovation Agency (BRIN), Mataram, Nusa Tenggara Barat, Indonesia
| | - Vinh Huynh-Phuoc
- Laboratory of Molecular Fish Immunology and Genetics, Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Research Center for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, Taiwan
- College of Aquaculture and Fisheries, Can Tho University, Can Tho, Vietnam
| | - B R J Castillo-Corea
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Omkar Vijay Byadgi
- International Program in Ornamental Fish Technology and Aquatic Animal Health, International College, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Ta-Chih Cheng
- Laboratory of Molecular Fish Immunology and Genetics, Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, Taiwan.
- Research Center for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, Taiwan.
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Huynh-Phuoc V, Ly TQ, Purbiantoro W, Ngo HVT, Afonso F, Vu NU, Cheng TC. Bacillus safensis isolated from white-leg shrimp, Penaeus vannamei in Taiwan with antagonistic activity against common Vibrio pathogens. Biocatalysis and Agricultural Biotechnology 2022. [DOI: 10.1016/j.bcab.2022.102477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Pham TH, Rao S, Cheng TC, Wang PC, Chen SC. The moonlighting protein fructose 1,6-bisphosphate aldolase as a potential vaccine candidate against Photobacterium damselae subsp. piscicida in Asian sea bass (Lates calcarifer). Dev Comp Immunol 2021; 124:104187. [PMID: 34186149 DOI: 10.1016/j.dci.2021.104187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 06/25/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
Vaccination is the most effective, safe, and environmentally friendly method to prevent the outbreak of Photobacterium damselae subsp. piscicida (Phdp), a dangerous pathogen in aquaculture worldwide. Here, recombinant proteins of catalase, superoxide dismutase, isocitrate dehydrogenase, fructose 1,6-bisphosphate aldolase (Fba), and a mixture of all four proteins were investigated for their immunoprotective effects against photobacteriosis in Asian sea bass (Lates calcarifer). After immunization, experimental fish showed an increase in specific antibody levels and lysozyme activities, especially the Fba group. After a lethal challenge with Phdp strain AOD105021, the Fba group achieved the highest relative percentage of survival rate (70.21%) and a significantly lower bacterial load in the spleens than other groups 3 days after infection. The results suggest that Fba is a good candidate for subunit vaccine development against photobacteriosis in fish.
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Affiliation(s)
- Trung Hieu Pham
- International Degree Program of Ornamental Fish Technology and Aquatic Animal Health, International College, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan.
| | - Shreesha Rao
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan.
| | - Ta-Chih Cheng
- Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Research Centre for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan.
| | - Pei-Chi Wang
- International Degree Program of Ornamental Fish Technology and Aquatic Animal Health, International College, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Research Centre for Fish Vaccine and Diseases, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Southern Taiwan Fish Diseases Research Centre, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan.
| | - Shih-Chu Chen
- International Degree Program of Ornamental Fish Technology and Aquatic Animal Health, International College, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Research Centre for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Research Centre for Fish Vaccine and Diseases, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Southern Taiwan Fish Diseases Research Centre, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan.
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Cheng TC, Arnold ADA, Chow JC, Shun-Shin MJSS, Howard JPH, Keene DK, Ali NA, Miyazawa AM, Varnava AV, Kanagaratnam PK, Ng FSN, Peters NSP, Francis DPF, Whinnett ZIW. His resynchronization therapy produces more physiological ventricular repolarisation compared with biventricular pacing. Europace 2021. [DOI: 10.1093/europace/euab116.441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): British Heart Foundation
BACKGROUND
Biventricular pacing (BVP) is known to shorten activation time in patients with heart failure and left bundle branch block (LBBB) but its effects on repolarisation are not well studied. His bundle pacing (HBP) can correct LBBB to deliver cardiac resynchronization therapy (HBP-CRT), producing more physiological ventricular activation time and pattern than BVP. It is not known whether this translates to more physiological repolarisation, and if so whether the effect is mediated through its effects on activation.
PURPOSE
We measured the effects of HBP-CRT and BVP on left ventricular repolarisation using non-invasive epicardial mapping (ECGI).
METHODS
Patients were recruited in two groups. 1) Patients scheduled for clinically indicated BVP procedures for heart failure with LBBB, 2) Individuals with narrow QRS, normal ventricular function and intact conduction systems. Using non-invasive electrocardiographic imaging, we identified patients with LBBB in whom HBP shortened ECGI-derived left ventricular (LV) activation time by >10ms. We compared the effects of HBP and BVP on ECGI-derived dispersion of LV repolarisation times and activation-recovery intervals (a surrogate for action potential duration).
RESULTS
21 patients in whom HBP shortened LV activation time by >10ms and an equal number of individuals with narrow intrinsic QRS were recruited. LV repolarisation dispersion was reduced by HBP-CRT (-42.0 ms, 95% confidence interval (CI): -52.3 to -31.7 ms, p <0.001) but not by BVP (11.9 ms, 95% CI: -6.24 to 30.1 ms, p = 0.182). The mean within-patient change in LV repolarisation dispersion from BVP to HBP-CRT was -56.5 ms (95% CI: -70.5 to -42.5 ms, p < 0.001). LV repolarisation dispersion with HBP-CRT was not different from individuals with narrow intrinsic QRS (2.75 ms, 95% CI: -16.2 to 21.7 ms, p = 0.981). The magnitude of reduction in LV repolarisation dispersion with HBP-CRT from intrinsic LBBB appeared similar to the magnitude of LV activation time shortening (-54.9 ms, 95% CI: -68.2 to -41.6 ms, p < 0.001). However, LV activation-recovery interval dispersion was also reduced by HBP-CRT (-44.3 ms, 95% CI: -69.2 to -19.3 ms, p < 0.001). Repolarisation mapping demonstrated normalisation of repolarisation pattern by HBP-CRT.
CONCLUSIONS
HBP-CRT can normalise repolarisation dispersion, producing more physiological repolarisation compared with BVP, which does not resolve the repolarisation abnormality of LBBB. HBP-CRT improves repolarisation through both activation resynchronization and modulation of action-potential duration. If these acute results translate to longer term outcomes, HBP-CRT may reduce the risk of ventricular arrhythmias in heart failure with LBBB to a greater extent than BVP. Abstract Figure. Epicardial Repolarisation Maps
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Affiliation(s)
- TC Cheng
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
| | - ADA Arnold
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
| | - JC Chow
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
| | - MJS-S Shun-Shin
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
| | - JPH Howard
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
| | - DK Keene
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
| | - NA Ali
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
| | - AM Miyazawa
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
| | - AV Varnava
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
| | - PK Kanagaratnam
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
| | - FSN Ng
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
| | - NSP Peters
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
| | - DPF Francis
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
| | - ZIW Whinnett
- National Heart and Lung Institute Imperial College, London, United Kingdom of Great Britain & Northern Ireland
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Pham TH, Cheng TC, Wang PC, Chen SC. Protective efficacy of four heat-shock proteins as recombinant vaccines against photobacteriosis in Asian seabass (Lates calcarifer). Fish Shellfish Immunol 2021; 111:179-188. [PMID: 33556554 DOI: 10.1016/j.fsi.2021.02.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 01/26/2021] [Accepted: 02/02/2021] [Indexed: 06/12/2023]
Abstract
Photobacterium damselae subsp. piscicida (Phdp) is the causative agent of photobacteriosis in marine fish and is responsible for huge losses to marine aquaculture worldwide. Efforts have been made to develop a vaccine against this disease. Heat-shock proteins (HSPs) are a family of proteins that are ubiquitous in cellular life. Bacteria produce elevated levels of HSPs as a survival strategy when exposed to stressful environments in a host during infection. This group of proteins are also important antigens that can induce both humoral and cellular immune responses. In this study, four HSPs of Phdp, HSP90, HSP33, HSP70, and DnaJ, were selected for cloning and recombinant expression. Western blotting with rabbit anti-Phdp helped identify rHSP70 and rHSP33 as immunogenic proteins. Asian seabass (Lates calcarifer) immunised with rHSP90, rHSP33, rHSP70, and rDnaJ showed 48.28%, 62.07%, 51.72%, and 31.03% relative percent survival, respectively, after being challenged with Phdp strain AOD105021. High expression levels of immune-related genes and high antibody titres were observed in the rHSP33 group, and the sera of this group also exhibited a high level of bactericidal activity against Phdp. Collectively, our results suggest that HSP33 is a potential candidate for vaccine development against Phdp infection.
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Affiliation(s)
- Trung Hieu Pham
- International Degree Program of Ornamental Fish Technology and Aquatic Animal Health, International College, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan.
| | - Ta-Chih Cheng
- Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Research Centre for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan.
| | - Pei-Chi Wang
- International Degree Program of Ornamental Fish Technology and Aquatic Animal Health, International College, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Southern Taiwan Fish Diseases Research Centre, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan.
| | - Shih-Chu Chen
- International Degree Program of Ornamental Fish Technology and Aquatic Animal Health, International College, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Southern Taiwan Fish Diseases Research Centre, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Research Centre for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan.
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Pham TH, Cheng TC, Wang PC, Chen SC. Genotypic diversity, and molecular and pathogenic characterization of Photobacterium damselae subsp. piscicida isolated from different fish species in Taiwan. J Fish Dis 2020; 43:757-774. [PMID: 32419196 DOI: 10.1111/jfd.13173] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 03/16/2020] [Accepted: 03/17/2020] [Indexed: 06/11/2023]
Abstract
Photobacteriosis, caused by Photobacterium damselae subsp. piscicida (Phdp), is a serious disease in marine fish species worldwide. To date, the epidemiological characterization of this pathogen in Taiwan remains limited. In this study, we collected 39 Phdp isolates obtained from different farmed fish for phenotypic and genotypic analysis. Phenotype bioassays using API-20E and API-20NE systems showed that the Phdp is a homogeneous group. However, genotyping using the pulsed-field gel electrophoresis (PFGE) technique revealed genetic variability among Phdp isolates when 13 and 11 different PFGE band patterns were obtained with SmaI and NotI as restriction enzymes, respectively. Phylogenetic analysis using 16S rDNA and the Fur gene clustered Taiwanese isolates and other species of P. damselae in the same clade. In contrast, the ToxR phylogenetic tree, a powerful discriminatory marker, separated the two subspecies. Furthermore, the virulence-associated genes, AIP56, P55, PDP_0080, Sod and Irp1, were detected from all isolates. Virulence testing with nine representative isolates in cobia (Rachycentron canadum) and Asian sea bass (Lates calcarifer) showed that some were highly pathogenic with 80%-100% mortality rates. This study provides epidemiological data of Phdp infections in farmed fish in Taiwan, which is necessary to develop comprehensive prevention and control strategies for the disease.
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Affiliation(s)
- Trung Hieu Pham
- International Degree Program of Ornamental Fish Technology and Aquatic Animal Health, International College, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Ta-Chih Cheng
- Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Research Centre for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Pei-Chi Wang
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Southern Taiwan Fish Diseases Research Centre, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Shih-Chu Chen
- International Degree Program of Ornamental Fish Technology and Aquatic Animal Health, International College, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Research Centre for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
- Southern Taiwan Fish Diseases Research Centre, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan
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Tran HB, Rizky PN, McDaniel Padgett SR, Lee YH, Chaung HC, Cheng TC. Molecular characterization of cobia (Rachycentron canadum) CD4 homologues revealed the first evidence of soluble CD4 in fish. Fish Shellfish Immunol 2020; 99:239-242. [PMID: 32058099 DOI: 10.1016/j.fsi.2020.02.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 02/06/2020] [Accepted: 02/10/2020] [Indexed: 06/10/2023]
Abstract
The co-receptor CD4 plays an important role in distinguishing between helper T-cell (Th) and cytotoxic T lymphocyte (CTL). In the present study, we investigated the molecular features of CD4-2 cDNA to facilitate understanding of their roles in cobia (Rachycentron canadum). Two CD4-2 molecules have been identified and exhibited 16.10% amino acids identity with each other. The cDNA of CD4-2A consists of a 993 bp ORF encoding 330 aa with long intracytoplasmic tail containing conserved protein tyrosine kinase p56Lck binding (C-X-C) motif, a transmembrane region, and two extracellular Ig-like (Ig-like) domains are predicted. Comparatively, the cDNA of cobia CD4-2B consists of a 990 bp ORF encoding 329 aa without a transmembrane domain as well as C-X-C motif, and three Ig-like domains are present. Homology comparison showed that the CD4-2A aa sequence of cobia showed high similarity and similar structural features to CD4-2 from other species, while the deduced CD4-2B protein shares higher structural similarity to CD4-1 group. Phylogenetic analysis indicated that cobia CD4-2A was closer with CD4-2 molecules in other fish species, distant from the clade formed by fish CD4-1 and mammalian CD4 sequences. However, cobia CD4-2B grouped with other known teleost CD4-1 sequences. The expression pattern of CD4-2A and CD4-2B mRNA during the embryonic development followed the trend of an initial increase after fertilized, providing evidence of maternal transfer of CD4-2 homologues to the developing cobia embryos and larvae. All of these results are useful for better understanding of cell-mediated immunity of cobia.
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Affiliation(s)
- Hung Bao Tran
- Laboratory of Molecular Fish Immunology and Genetics, Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Research Center for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan.
| | - Putri Nurhanida Rizky
- Laboratory of Molecular Fish Immunology and Genetics, Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Polytechnic of Marine and Fisheries Sidoarjo, Department of Aquaculture, East Java, 61253, Indonesia
| | - Stanley Rob McDaniel Padgett
- Laboratory of Molecular Fish Immunology and Genetics, Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan
| | - Yen-Hung Lee
- Tungkang Biotechnology Research Center, Fisheries Research Institute, Taiwan
| | - Hso-Chi Chaung
- Research Center for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Department of Veterinary Medicine, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan
| | - Ta-Chih Cheng
- Laboratory of Molecular Fish Immunology and Genetics, Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan; Research Center for Animal Biologics, National Pingtung University of Science and Technology, Pingtung, 91201, Taiwan.
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Tran HB, Chen SC, Chaung HC, Cheng TC. Molecular cloning of IL-6, IL-10, IL-11, IFN-ɤ and modulation of pro- and anti-inflammatory cytokines in cobia (Rachycentron canadum) after Photobacterium damselae subsp. piscicida infection. Comp Biochem Physiol B Biochem Mol Biol 2019; 230:10-18. [DOI: 10.1016/j.cbpb.2019.01.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 12/19/2018] [Accepted: 01/09/2019] [Indexed: 02/08/2023]
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Tran HB, Lee YH, Guo JJ, Cheng TC. De novo transcriptome analysis of immune response on cobia (Rachycentron canadum) infected with Photobacterium damselae subsp. piscicida revealed inhibition of complement components and involvement of MyD88-independent pathway. Fish Shellfish Immunol 2018; 77:120-130. [PMID: 29578048 DOI: 10.1016/j.fsi.2018.03.041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 03/02/2018] [Accepted: 03/21/2018] [Indexed: 06/08/2023]
Abstract
Cobia, Rachycentron canadum, one of the most important aquatic species in Taiwan, has suffered heavy losses from Photobacterium damselae subsp. piscicida, which is the causal agent of photobacteriosis. In this study, the transcriptomic profiles of livers and spleens from Pdp-infected and non-infected cobia were obtained for the first time by Illumina-based paired-end sequencing method with a focus on immune-related genes. In total, 164,882 high quality unigenes were obtained in four libraries. Following Pdp infection, 7302 differentially expressed unigenes from liver and 8600 differentially expressed unigenes from spleen were identified. Twenty-seven of the differently expressed genes were further validated by RT-qPCR (average correlation coefficient 0.839, p-value <0.01). Results indicated a negative regulation of complement components and increased expression of genes involved in MyD88-independent pathway. Moreover, a remarkable finding was the increased expression of IL-10, implying an inadequacy of immune responses. This study not only characterized several putative immune pathways, but also provided a better understanding of the molecular responses to photobacteriosis in cobia.
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Affiliation(s)
- Hung Bao Tran
- Laboratory of Molecular Fish Immunology and Genetics, Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung 91201, Taiwan; Research Center for Animal Biologics, National Pingtung University of Science and Technology, Pingtung 91201, Taiwan
| | - Yen-Hung Lee
- Tungkang Biotechnology Research Center, Fisheries Research Institute, Pingtung 92845, Taiwan
| | - Jiin-Ju Guo
- Tungkang Biotechnology Research Center, Fisheries Research Institute, Pingtung 92845, Taiwan
| | - Ta-Chih Cheng
- Laboratory of Molecular Fish Immunology and Genetics, Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung 91201, Taiwan; Research Center for Animal Biologics, National Pingtung University of Science and Technology, Pingtung 91201, Taiwan.
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Pi GL, Bi JP, He HP, Li Y, Cheng TC, Li YP. [The protective effect of optimized target delineation in intensity modulated radiation therapy on swallowing function in patients with different TNM staging of nasopharyngeal carcinoma]. Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2018; 32:617-620. [PMID: 29798149 DOI: 10.13201/j.issn.1001-1781.2018.08.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Indexed: 11/12/2022]
Abstract
Objective:To investigate the protective effect of optimized target delineation in intensity modulated radiation therapy(IMRT) on swallowing function in patients with different TNM staging of nasopharyngeal carcinoma.Method:Fifty patients with nasopharyngeal carcinoma were enrolled in this study. They were randomly divided into 25 cases of experimental group and 25 cases of control group by random number table and received IMRT treatment. Patients in control group only received routine delineation of target areas, the patients in experimental group were given the delineation of the relevant parts of the swallowing on the basis of the control group.And then, the degree of dysphagia, xerostomia, weight loss, and quality of life were assessed in the two groups of patients during and after IMRT.Result:There was no significant change in the degree of dysphagia in stage Ⅱ patients during radiotherapy, but the degree of dysphagia in stage Ⅲ and Ⅳ patients increased with the increase of radiotherapy time. After the end of radiotherapy, there was no significant change in the degree of dysphagia in the control group of patients. Compared with the 0th week after the end of radiotherapy, the stage Ⅱ patients in experimental group showed significant improvement in week 12(P<0.05), while the stage Ⅲ and Ⅳ patients showed significant improvement in week 24 after radiotherapy(P<0.05). The degree of xerostomia of two groups of patients continued to increase with varying degrees during and after IMRT(P<0.05 or P<0.01). The weight of the two groups of patients during radiotherapy continued to decrease with the increase of radiotherapy time,and gradually recovered after the end of radiotherapy.And in the experimental group, the weight loss was significantly lower in week 12 and week 24 than in the control group (P<0.05). During radiotherapy, the quality of life scores of the two groups became lower and lower with the increase of radiotherapy time compared with the 0th week of radiotherapy. After the end of radiotherapy, the quality of life began to gradually improve, and in week 24 after the end of radiotherapy, the quality of life of the experimental group of patients was significantly higher than that of the control group (P<0.05).Conclusion:During radiotherapy of patients with nasopharyngeal carcinoma, the structural organs associated with swallowing function are given individualized target delineation can reduce the occurring of dysphagia due to radiotherapy and improve the quality of life of patients after radiotherapy.
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Affiliation(s)
- G L Pi
- Head and Neck Radiotherapy Ward 1, Hubei Cancer Hospital, Wuhan, 430079, China
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Edney LC, Haji Ali Afzali H, Cheng TC, Karnon J. Mortality reductions from marginal increases in public spending on health. Health Policy 2018; 122:892-899. [PMID: 29759682 DOI: 10.1016/j.healthpol.2018.04.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 04/20/2018] [Accepted: 04/21/2018] [Indexed: 10/17/2022]
Abstract
There is limited empirical evidence of the nature of any relationship between health spending and health outcomes in Australia. We address this by estimating the elasticity of health outcomes with respect to public healthcare spending using an instrumental variable (IV) approach to account for endogeneity of healthcare spending to health outcomes. Results suggest that, based on the conditional mean, a 1% increase in public health spending was associated with a 2.2% (p < 0.05) reduction in the number of standardised Years of Life Lost (YLL). Sensitivity analyses and robustness checks supported this conclusion. Further exploration using IV quantile regression indicated that marginal returns on public health spending were significantly greater for areas with poorer health outcomes compared to areas with better health outcomes. On average, marginal increases in public health spending reduce YLL, but areas with poorer health outcomes have the greatest potential to benefit from the same marginal increase in public health spending compared to areas with better health outcomes. Understanding the relationship between health spending and outcomes and how this differs according to baseline health outcomes can help meet dual policy objectives to improve the productivity of the healthcare system and reduce inequity.
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Affiliation(s)
- L C Edney
- School of Public Health, University of Adelaide, Level 9, Adelaide Health and Medical Sciences Building, The University of Adelaide, 5005, Australia.
| | - H Haji Ali Afzali
- School of Public Health, University of Adelaide, Level 9, Adelaide Health and Medical Sciences Building, The University of Adelaide, 5005, Australia
| | - T C Cheng
- School of Economics, University of Adelaide, Level 4, 10 Pulteney Street, The University of Adelaide, 5005, Australia
| | - J Karnon
- School of Public Health, University of Adelaide, Level 9, Adelaide Health and Medical Sciences Building, The University of Adelaide, 5005, Australia
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Cheung TK, Cheng TC, Wong LY. Willingness for deceased organ donation under different legislative systems in Hong Kong: population-based cross-sectional survey. Hong Kong Med J 2018; 24:119-127. [PMID: 29633715 DOI: 10.12809/hkmj176831] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
INTRODUCTION Under the current opt-in system, the deceased organ donation rate remains low in Hong Kong. An opt-out system and an opt-in system combined with organ allocation priority (ie, priority to donors as transplant recipients) have been proposed to encourage willingness among the general population towards deceased organ donation. This study aimed to compare willingness, and its determinants, across these three legislative systems. METHODS A random telephone survey of Hong Kong permanent residents aged ≥18 years was conducted between August and October 2016 using an anonymous questionnaire. Willingness towards deceased organ donation was compared between the legislative systems with McNemar's test. Determinants of willingness were tested by logistic regression. RESULTS The proportion of those willing to consider deceased organ donation under the current opt-in system would significantly increase after combining it with allocation priority (64.5% vs 73.4%; P=0.018). "Fairness or reciprocity" was the major reported reason underlying the increase. In contrast, willingness would decrease after introducing the opt-out system (60.1%), although not significantly (P=0.336). The reduction might be attributable to a "belief of being forced to donate". Under the allocation priority system, reduced willingness to donate was associated with advanced age, lower educational attainment, and lower monthly household income. Under the opt-out system, reduced willingness was associated with being married, having a lower household income, and distrust of local government. CONCLUSIONS An opt-in system with allocation priority could induce willingness to donate, whereas an opt-out system may reduce willingness. The findings have implications for policy-making and promotion of organ donation.
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Affiliation(s)
- T K Cheung
- The Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - T C Cheng
- The Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - L Y Wong
- The Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
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13
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Byadgi O, Puteri D, Lee YH, Lee JW, Cheng TC. Identification and expression analysis of cobia (Rachycentron canadum) Toll-like receptor 9 gene. Fish Shellfish Immunol 2014; 36:417-427. [PMID: 24378677 DOI: 10.1016/j.fsi.2013.12.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Revised: 12/13/2013] [Accepted: 12/19/2013] [Indexed: 06/03/2023]
Abstract
Cobia culture is hindered by bacterial infection (Photobacterium damselae subsp. piscicida) and in order to study the effect of P. damselae subsp. piscicida challenge and CpG ODN stimulation on cobia Toll like receptor 9 (RCTLR9), we used PCR to clone RCTLR9 gene and qRT-PCR to quantify gene expression. The results indicated that RCTLR9 cDNA contains 3141 bp. It encodes 1047 amino acids containing 16 typical structures of leucine-rich repeats (LRRs) including an LRRTYP, LRRCT and a motif involved in PAMP binding was identified at position 240-253 amino acid. Broad expression of RCTLR9 was found in larval, juvenile and adult stages irrespective of the tissues. In larval stage, RCTLR9 mRNA expression decreased at 5 d and then increased at 10 dph. At juvenile stage cobia, the expression was significantly high (p < 0.05) in spleen and intestine compared to gill, kidney, liver and skin. However, at adult stage, the significant high expression was found in gill and intestine. Cobia challenged with P. damselae subsp. piscicida showed significant increase in RCTLR9 expression at 24 h post challenge in intestine, spleen and liver, while in kidney the expression was peak at 12 h and later it decreased at 24 h. The highest expression was 40 fold increase in spleen and the lowest expression was ∼3.6 fold increase in liver. Cobia stimulated with CpG oligonucleotides showed that the induction of these genes was CpG ODN type and time dependent. In spleen and liver, CpG ODNs 1668 and 2006 injected group showed high expression of RCTLR9, IL-1β, chemokine CC compared to other groups. Meanwhile, CpG ODN 2006 has induced high expression of IgM. The CpG ODNs 2395 have induced significant high expression of Mx in spleen and liver. These results demonstrates the potential of using CpG ODN to enhance cobia resistance to P. damselae subsp. piscicida infection and use as an adjuvant in vaccine development.
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Affiliation(s)
- Omkar Byadgi
- Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Dinda Puteri
- Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, Taiwan; Department of Fisheries and Marine Science, University of Brawijaya, Malang, Indonesia
| | - Yan-Horn Lee
- Tungkang Biotechnology Research Center, Fisheries Research Institute, Council of Agriculture, Pingtung, Taiwan
| | - Jai-Wei Lee
- Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Ta-Chih Cheng
- Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, Taiwan.
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14
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Young JW, Cheng TC, Bandyopadhyay B, Duncan MA. IR photodissociation spectroscopy of H7(+), H9(+), and their deuterated analogues. J Phys Chem A 2013; 117:6984-90. [PMID: 23374094 DOI: 10.1021/jp312630x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cluster ions of H7(+)/D7(+) and H9(+)/D9(+) produced in a supersonic molecular beam with a pulsed discharge source are mass selected and studied with infrared laser photodissociation spectroscopy. Photodissociation occurs by the loss of H2 (D2) from each cluster, producing resonances in the 2000-4500 cm(-1) region. Vibrational patterns indicate that these ions consist of an H3(+) (D3(+)) core ion solvated by H2 (D2) molecules. There is no evidence for the shared proton structure seen previously for H5(+). The H3(+) ion core vibrational bands are weakened and broadened significantly, presumably by enhanced rates of intramolecular vibrational relaxation. Computational studies at the DFT/B3LYP or MP2 levels of theory (including scaling) are adequate to reproduce qualitative details of the vibrational spectra, but neither provides quantitative agreement with vibrational frequencies.
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Affiliation(s)
- J W Young
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
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15
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Abstract
In this paper, we present a selective and differential medium, termed Vibrio alginolyticus (VAL) agar, developed for the isolation and identification of V. alginolyticus. The presence of bile salts, high salinity and high incubation temperature allows the selective growth of moderately halophilic Vibrio species. Differentiation of bacteria is achieved by identifying species capable of sucrose fermentation, made visible by the pH indicator bromocresol purple. In this study, all of the 26 strains of V. alginolyticus and only three of the 99 strains representing 30 species (including 19 Vibrio species) other than V. alginolyticus were able to grow in the VAL medium. The remaining three strains could be further differentiated from V. alginolyticus according to colour or the diameter of colonies produced on VAL agar plates. Colonies isolated from shellfish rearing water and infected shrimp through the use of VAL agar plates were all positively identified as V. alginolyticus by conventional tests and 16S rDNA sequencing. The testing of specificity and differentiation capability of VAL shows the potential of the agar as a medium for the primary isolation of V. alginolyticus from pathological and environmental samples.
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Affiliation(s)
- C-I Chang
- Aquaculture Division, Fisheries Research Institute, Council of Agriculture, Keelung, Taiwan.
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16
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Lin TC, Truong TK, Chen SH, Wang LJ, Cheng TC. Simplified 2-D cubic spline interpolation scheme using direct computation algorithm. IEEE Trans Image Process 2010; 19:2913-2923. [PMID: 20494853 DOI: 10.1109/tip.2010.2050723] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
It has been shown that the 2-D cubic spline interpolation (CSI) proposed by Truong et al. is one of the best algorithms for image resampling or compression. Such a CSI algorithm together with the image coding standard, e.g., JPEG, can be used to obtain a modified image codec while still maintaining a good quality of the reconstructed image for higher compression ratios. In this paper, a fast direct computation algorithm is developed to improve the computational efficiency of the original FFT-based 2-D CSI methods. In fact, this algorithm computes the 2-D CSI directly without explicitly calculating the complex division usually needed in the FFT or Winograd discrete Fourier transform (WDFT) algorithm. In addition, this paper describes a novel way to derivate the 2-D CSI from the 1-D CSI by using the row-column method. This new fast 2-D CSI provides a regular and simple structure based upon linear correlations. Therefore, it can be implemented by the use of a modification of Kung’s pipeline structure and is naturally suitable for VLSI implementations. Experimental results show that the proposed new fast 2-D CSI algorithm can achieve almost the same CSI performance with much fewer arithmetic operations in comparison with existing efficient algorithms.
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Abstract
Electron field emission from a single nanoemitter is a barrier tunneling, quantum mechanical process that can, therefore, be described by the well-known Fowler-Nordheim (FN) equation. At high emission current densities, however, the space charge caused by the cathode may affect the current density-voltage (J-V) characteristics predicted by the FN theory. In this study, we theoretically investigated the effect of space charge on FE nanodevices, including diode and triode structures. The J-V characteristics of FE nanodevices were obtained by analytically (diode structures) or numerically (triode structures) solving the coupled FN equation and Poisson's equation. We discuss the behavior of FE nanodiodes and nanotriodes displaying different geometries, dimensions and work functions of their emitter materials. In the high current density region, space charge plays an important role in FE nanodevices; the threshold current density of space-charge limitation is related to the electric field distributions. Besides, our theoretical results are in good agreement with the experimental results reported previously.
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Affiliation(s)
- P Y Chen
- Sky-watcher Telescope and Optics Corp., Richmond, British Columbia V7A5C8, Canada.
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18
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Chang CY, Hsieh YH, Hsieh LL, Yao KS, Cheng TC. Establishment of activity indicator of TiO2 photocatalytic reaction--hydroxyl radical trapping method. J Hazard Mater 2009; 166:897-903. [PMID: 19150747 DOI: 10.1016/j.jhazmat.2008.11.092] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2008] [Revised: 11/25/2008] [Accepted: 11/25/2008] [Indexed: 05/27/2023]
Abstract
In this study, a new, low cost and easy method, hydroxyl radical trapping method, was employed to investigate the photo-activity of UV/TiO2 photocatalytic reaction. The Taguchi method was utilized to optimize the preparation of titanium dioxide (TiO2) thin-film reactor through the modified chemical vapor deposition (CVD) method. The optimal yield of hydroxyl radicals was then evaluated by calculating the conversion ratio of salicylic acid under the optimal conditions. In the experiments, salicylic acid was used as the free-radical scavenger and the formation of three different intermediates were examined to shed light on the trend and kinetics of reaction of hydroxyl radical with organic substance under different operation conditions. The results indicated that the yield of hydroxyl radicals increased with increasing irradiation intensity and dissolved oxygen level. The optimal experimental conditions obtained in this study were irradiation with intensity of 2.9 mW cm(-2) on salicylic acid at concentration of 250 mg L(-1) by both agitation and aeration processes (dissolved oxygen level=8.2 mg O(2)L(-1)) at pH 5. Such conditions could achieve the optimal hydroxyl radical yield of 5.1 x 10(-17)M.
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Affiliation(s)
- Chen-Yu Chang
- Department of Life Science, Ming-Dao University, 369 Wen-Hua Road, Peetow, Chang-Hua County 52345, Taiwan.
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19
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Chang CY, Hsieh YH, Cheng KY, Hsieh LL, Cheng TC, Yao KS. Effect of pH on Fenton process using estimation of hydroxyl radical with salicylic acid as trapping reagent. Water Sci Technol 2008; 58:873-879. [PMID: 18776624 DOI: 10.2166/wst.2008.429] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This study estimates the yield of hydroxyl radical using salicylic acid as the trapping reagent and investigates the relationship between hydroxyl radical and pH value. The formation and variation of hydroxyl radical under different pH values were evaluated using reaction products, 2,3-DHBA, 2,5-DHBA, and catechol. The formation rate of hydroxyl radical was dependent on the ratio of ferrous ion to hydrogen peroxide and pH values. The difference between various pH values was explored. The kinetics and mechanisms of hydroxyl radical reactions were established in the Fenton process. Experimental results showed that the best reaction conditions were 8.5 mM H(2)O(2), 1.25 mM Fe(2 + ), Fe(2 + )/H(2)O(2) = 0.147 at pH 3 and the formation rate constant of hydroxyl radical was 1.12 x 10(11) M(-1) s(-1).
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Affiliation(s)
- Chen-Yu Chang
- Department of Life Science, Ming-Dao University, Peetow, Chang-Hua County, Chinese Taiwan.
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20
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Chuang FT, Chen PY, Cheng TC, Chien CH, Li BJ. Improved field emission properties of thiolated multi-wall carbon nanotubes on a flexible carbon cloth substrate. Nanotechnology 2007; 18:395702. [PMID: 21730427 DOI: 10.1088/0957-4484/18/39/395702] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
In this paper we report the observation of enhanced field emission properties from thiolated multi-wall carbon nanotubes (MWCNTs) produced by a simple and effective two-step chemical surface modification technique. This technique implements carboxylation and thiolation on the MWCNTs synthesized by microwave plasma chemical vapor deposition (MPCVD) on the flexible carbon cloth substrate. The resulting thiolated MWCNTs were found to have a very low threshold field value of 1.25 V µm(-1) and a rather high field enhancement factor of 1.93 × 10(4), which are crucial for applications in versatile vacuum microelectronics.
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Affiliation(s)
- F T Chuang
- Department of Material Science and Engineering, National Chiao-Tung University, Hsinchu 30050, Taiwan, Republic of China
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21
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Abstract
Malignant mesothelioma of the tunica vaginalis is rare, and is usually not diagnosed until surgery is undertaken. Reports on the ultrasound features of this tumour are limited. We present an unusual case with ultrasound features mimicking an adenomatoid tumour.
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Affiliation(s)
- C W Mak
- Department of Diagnostic Radiology, Chi-Mei Foundation Medical Center, 901 Chung Hwa Road, Yung Kang, Tainan, Taiwan, Republic of China
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22
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Chen CH, Tzeng CC, Cheng TC, Chiu AW. Angiomyolipoma of kidney as a part of tuberous sclerosis complex. J Postgrad Med 2003; 49:278-9. [PMID: 14597797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023] Open
Affiliation(s)
- C H Chen
- Division of Urology, Department of Surgery, Department of Pathology, Chi Mei Medical Center, Tainan, Taiwan
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23
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Fan EW, Cheng TC, Chiu AW, Lin H. Pyonephrosis and urinary retention secondary to a large Gartner's duct cyst associated with single ectopic ureter in a pregnant woman. BJU Int 2002; 89:136-7. [PMID: 11849179 DOI: 10.1046/j.1464-4096.2001.00935.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- E W Fan
- Division of Urology, Department of Surgery, Chi-Mei Foundation Hospital, Tainan, Taiwan, ROC
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24
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Said JW, Hoyer KK, French SW, Rosenfelt L, Garcia-Lloret M, Koh PJ, Cheng TC, Sulur GG, Pinkus GS, Kuehl WM, Rawlings DJ, Wall R, Teitell MA. TCL1 oncogene expression in B cell subsets from lymphoid hyperplasia and distinct classes of B cell lymphoma. J Transl Med 2001; 81:555-64. [PMID: 11304575 DOI: 10.1038/labinvest.3780264] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Activation of the TCL1 oncogene has been implicated in T cell leukemias/lymphomas and recently was associated with AIDS diffuse large B cell lymphomas (AIDS-DLBCL). Also, in nonmalignant lymphoid tissues, antibody staining has shown that mantle zone B cells expressed abundant Tcl1 protein, whereas germinal center (GC; centrocytes and centroblasts) B cells showed markedly reduced expression. Here, we analyze isolated B cell subsets from hyperplastic tonsil to determine a more precise pattern of Tcl1 expression with development. We also examine multiple B cell lines and B lymphoma patient samples to determine whether different tumor classes retain or alter the developmental pattern of expression. We show that TCL1 expression is not affected by Epstein-Barr virus (EBV) infection and is high in naïve B cells, reduced in GC B cells, and absent in memory B cells and plasma cells. Human herpesvirus-8 infected primary effusion lymphomas (PEL) and multiple myelomas are uniformly TCL1 negative, whereas all other transformed B cell lines tested express moderate to abundant TCL1. This observation supports the hypothesis that PEL, like myeloma, usually arise from post-GC stages of B cell development. Tcl1 protein is also detected in most naïve/GC-derived B lymphoma patient samples (23 of 27 [85%] positive), whereas most post-GC-derived B lymphomas lack expression (10 of 41 [24%] positive). These data indicate that the pattern of Tcl1 expression is distinct between naïve/GC and post-GC-derived B lymphomas (P < 0.001) and that the developmental pattern of expression is largely retained. However, post-GC-derived AIDS-DLBCL express TCL1 at a frequency equivalent to naïve/GC-derived B lymphomas in immune-competent individuals (7 of 9 [78%] positive), suggesting that TCL1 down-regulation is adversely affected by severe immune system dysfunction. These findings demonstrate that TCL1 expression in B cell lymphoma usually reflects the stage of B cell development from which they derive, except in AIDS-related lymphomas.
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MESH Headings
- B-Lymphocyte Subsets/metabolism
- Cell Line, Transformed
- Cell Transformation, Viral
- DNA-Binding Proteins/metabolism
- Down-Regulation
- Gene Expression Regulation, Developmental
- Gene Expression Regulation, Neoplastic
- Herpesvirus 4, Human/pathogenicity
- Humans
- Hyperplasia/genetics
- Hyperplasia/metabolism
- Lymphoma, AIDS-Related/genetics
- Lymphoma, AIDS-Related/metabolism
- Lymphoma, B-Cell/classification
- Lymphoma, B-Cell/genetics
- Lymphoma, B-Cell/metabolism
- Lymphoma, Large B-Cell, Diffuse/metabolism
- Multiple Myeloma/genetics
- Multiple Myeloma/metabolism
- Palatine Tonsil/immunology
- Proto-Oncogene Proteins/biosynthesis
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins/metabolism
- Proto-Oncogene Proteins c-bcl-6
- RNA, Messenger/biosynthesis
- Transcription Factors/metabolism
- Tumor Cells, Cultured
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Affiliation(s)
- J W Said
- Department of Pathology, University of California at Los Angeles School of Medicine, 90095-1732, USA
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Abstract
Conditions were developed to cryopreserve cells from pronase-dissociated atria and ventricles of eastern oysters (Crassostrea virginica). The effect of three concentrations (5, 10, 15%) of the cryoprotectants (dimethyl sulfoxide, glycerol, and propylene glycol), three thawing temperatures (25, 45, 75 degrees C), and three cooling rates (slow, medium, fast) were compared. Cells were frozen at -80 degrees C and plunged in liquid nitrogen. Thawed cells were seeded in 96-well plates and primary cultures were evaluated after 3 d by measuring the metabolic activity using a tetrazolium compound, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, and by comparing the relative spreading of cells between treatments. The best conditions for freezing and thawing of cells for each cryoprotectant were selected and a final study was performed to compare cryoprotectants. For this final study, we measured the number of cells and their viability 3 d after thawing, in addition to determining cell metabolic activity and cell spreading. Primary cultures of cells fozen without cryoprotectant and of nonfrozen cells were used as controls in all studies. Atrial cells were best cryopreserved with glycerol at a concentration of 10%, a medium cooling rate, and thawing at 45 degrees C. After thawing, atrial cells showed 53+/-5% of the metabolic activity, 84+/-5% of the number, and 92+/-2% of the viability of nonfrozen cells. For ventricular cells, 10% glycerol, a medium cooling rate, and thawing at 25 degrees C yielded the best results. The thawed ventricular cells showed 83+/-5% of the metabolic activity, 91+/-5% of the number, and 96+/-2% of the viability of nonfrozen cells.
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Affiliation(s)
- T C Cheng
- Department of Veterinary Science, Louisiana State University Agricultural Center, Baton Rouge 70803, USA
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Chang WC, Hsieh YY, Cheng TC, Chang CC, Tsai HD, Lee MS. Effect of methylglyoxal on mouse embryogenesis. Chang Gung Med J 2001; 24:251-7. [PMID: 11413883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
BACKGROUND Methylglyoxal (MG), a highly active and mutagenetic compound, has been found widely in a variety of foods and beverages. We investigated the effect of MG on mouse embryo development in-vitro. METHODS Two-cell mouse embryos were divided into six groups according to the MG concentration in the culture medium: Group 1 (control group). 0 mM; Group 2, 10(-4) mM; Group 3, 10(-3) mM; Group 4, 10(-2) mM; Group 5, 10(-1) mM; Group 6, 1 mM. Embryo development and cleavage were compared every day for 5 days. RESULTS The percentages of embryos reaching blastocyst/hatching stages were as follows: Group 1, 66.8%/34.2%; Group 2, 67.9%/38.7%; Group 3, 56.2%/31.5%; Group 4, 39.4%/14.1%; Group 5, 11.4%/10.2%; Group 6, 0%/0%. Higher MG concentrations (> or = 10(-2) mM) were associated with morphological aberrations and blocked development of embryos. CONCLUSION The cutoff value of MG concentration on the mouse embryo development in-vitro is 10(-2) mM. An increased risk of embryotoxicity occurs with MG concentrations > or = 10(-2) mM in vitro. There were no significant effects on the growth rate at MG concentrations of 10(-3) and 10(-4) mM.
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Affiliation(s)
- W C Chang
- Department of Obstetrics and Gynecology, China Medical College Hospital, Taichung, Taiwan, R.O.C
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Hill CM, Li WS, Cheng TC, DeFrank JJ, Raushel FM. Stereochemical specificity of organophosphorus acid anhydrolase toward p-nitrophenyl analogs of soman and sarin. Bioorg Chem 2001; 29:27-35. [PMID: 11300693 DOI: 10.1006/bioo.2000.1189] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Organophosphorus acid anhydrolase (OPAA) catalyzes the hydrolysis of p-nitrophenyl analogs of the organophosphonate nerve agents, sarin and soman. The enzyme is stereoselective toward the chiral phosphorus center by displaying a preference for the R(P)-configuration of these analogs. OPAA also exhibits an additional preference for the stereochemical configuration at the chiral carbon center of the soman analog. The preferred configuration of the chiral carbon center is dependent upon the configuration at the phosphorus center. The enzyme displays a two- to four-fold preference for the R(P)-enantiomer of the sarin analog. The k(cat)/K(m) of the R(P)-enantiomer is 250 M(-1) s(-1), while that of the S(P)-enantiomer is 110 M(-1) s(-1). The order of preference for the stereoisomers of the soman analog is R(P)S(C) > R(P)R(C) > S(P)R(C) > S(P)S(C). The k(cat)/K(m) values are 36,300 M(-1)s(-1), 1250 M(-1) s(-1), 80 M(-1) s(-1) and 5 M(-1) s(-1), respectively. The R(P)S(C)-isomer of the soman analog is therefore preferred by a factor of 7000 over the S(P)S(C)-isomer.
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Affiliation(s)
- C M Hill
- Department of Chemistry, Texas A&M University, College Station, Texas 77842-3021, USA
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Petrikovics I, Cheng TC, Papahadjopoulos D, Hong K, Yin R, DeFrank JJ, Jaing J, Song ZH, McGuinn WD, Sylvester D, Pei L, Madec J, Tamulinas C, Jaszberenyi JC, Barcza T, Way JL. Long circulating liposomes encapsulating organophosphorus acid anhydrolase in diisopropylfluorophosphate antagonism. Toxicol Sci 2000; 57:16-21. [PMID: 10966507 DOI: 10.1093/toxsci/57.1.16] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
These studies are focused on antagonizing organophosphorous (OP) intoxications by a new conceptual approach using recombinant enzymes encapsulated within sterically stabilized liposomes to enhance diisopropylfluorophosphate (DFP) degradation. The OP hydrolyzing enzyme, organophosphorous acid anhydrolase (OPAA), encapsulated within the liposomes, was employed either alone or in combination with pralidoxime (2-PAM) and/or atropine. The recombinant OPAA enzyme, from the ALTEROMONAS: strain JD6, has high substrate specificity toward a wide range of OP compounds, e.g., DFP, soman, and sarin. The rate of DFP hydrolysis by liposomes containing OPAA (SL)* was measured by determining the changes in fluoride-ion concentration using a fluoride ion-selective electrode. This enzyme carrier system serves as a biodegradable protective environment for the OP-metabolizing enzyme (OPAA), resulting in an enhanced antidotal protection against the lethal effects of DFP. Free OPAA alone showed some antidotal protection; however, the protection with 2-PAM and/or atropine was greatly enhanced when combined with (SL)*.
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Affiliation(s)
- I Petrikovics
- Department of Medical Pharmacology and Toxicology, Texas A&M University, College of Medicine, College Station, Texas 77843-1114, USA
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Hill CM, Wu F, Cheng TC, DeFrank JJ, Raushel FM. Substrate and stereochemical specificity of the organophosphorus acid anhydrolase from Alteromonas sp. JD6.5 toward p-nitrophenyl phosphotriesters. Bioorg Med Chem Lett 2000; 10:1285-8. [PMID: 10866401 DOI: 10.1016/s0960-894x(00)00213-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The enzyme OPAA hydrolyzes p-nitrophenyl phosphotriesters bearing substituents at the phosphorus center ranging in size from methyl to phenyl. The enzyme exhibits stereoselectivity toward the hydrolysis of chiral substrates with a preference for the Sp enantiomer.
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Affiliation(s)
- C M Hill
- Department of Chemistry, Texas A&M University, College Station 77843, USA
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Petrikovics I, McGuinn WD, Sylvester D, Yuzapavik P, Jiang J, Way JL, Papahadjopoulos D, Hong K, Yin R, Cheng TC, DeFrank JJ. In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism. Drug Deliv 2000; 7:83-9. [PMID: 10892408 DOI: 10.1080/107175400266641] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022] Open
Abstract
This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.
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Affiliation(s)
- I Petrikovics
- Department of Medical Pharmacology and Toxicology, Texas A&M University, College of Medicine, College Station 77843-1114, USA
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31
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Cheng TC, Ramakrishnan V, Chan SI. Purification and characterization of a cobalt-activated carboxypeptidase from the hyperthermophilic archaeon Pyrococcus furiosus. Protein Sci 1999; 8:2474-86. [PMID: 10595552 PMCID: PMC2144183 DOI: 10.1110/ps.8.11.2474] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
A novel metallocarboxypeptidase (PfuCP) has been purified to homogeneity from the hyperthermophilic archaeon, Pyrococcus furiosus, with its intended use in C-terminal ladder sequencing of proteins and peptides at elevated temperatures. PfuCP was purified in its inactive state by the addition of ethylenediaminetetraacetic acid (EDTA) and dithiothreitol (DTT) to purification buffers, and the activity was restored by the addition of divalent cobalt (K, = 24 +/- 4 microM at 80 degrees C). The serine protease inhibitor phenylmethylsulfonyl fluoride (PMSF) had no effect on the activity. The molecular mass of monomeric PfuCP is 59 kDa as determined by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 58 kDa by SDS-PAGE analysis. In solution, PfuCP exists as a homodimer of approximately 128 kDa as determined by gel filtration chromatography. The activity of PfuCP exhibits a temperature optimum exceeding 90 degrees C under ambient pressure, and a narrow pH optimum of 6.2-6.6. Addition of Co2+ to the apoPfuCP at room temperature does not alter its far-UV circular dichroism (CD) or its intrinsic fluorescence spectrum. Even when the CoPfuCP is heated to 80 degrees C, its far-UV CD shows a minimal change in the global conformation and the intrinsic fluorescence of aromatic residues shows only a partial quenching. Changes in the intrinsic fluorescence appear essentially reversible with temperature. Finally, the far-UV CD and intrinsic fluorescence data suggest that the overall structure of the holoenzyme is extremely thermostable. However, the activities of both the apo and holo enzyme exhibit a similar second-order decay over time, with 50% activity remaining after approximately 40 min at 80 degrees C. The N-blocked synthetic dipeptide, N-carbobenzoxy-Ala-Arg (ZAR), was used in the purification assay. The kinetic parameters at 80 degrees C with 0.4 mM CoCl2 were: Km, 0.9 +/- 0.1 mM; Vmax, 2,300 +/- 70 U mg(-1); and turn over number, 600 +/- 20 s(-1). Activity against other ZAX substrates (X = V, L, I, M, W, Y, F, N, A, S, H, K) revealed a broad specificity for neutral, aromatic, polar, and basic C-terminal residues. This broad specificity was confirmed by the C-terminal ladder sequencing of several synthetic and natural peptides, including porcine N-acetyl-renin substrate, for which we have observed (by MALDI-TOF MS) stepwise hydrolysis by PfuCP of up to seven residues from the C-terminus: Ac-Asp-Arg-Val-Tyr-Ile-His-Pro-Phe-His-Leu-Leu-Val-Tyr-Ser.
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Affiliation(s)
- T C Cheng
- Noyes Laboratories, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena 91125, USA
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Huang CC, Cheng TC, Chang HH, Chang CC, Chen CI, Liu J, Lee MS. Birth after the injection of sperm and the cytoplasm of tripronucleate zygotes into metaphase II oocytes in patients with repeated implantation failure after assisted fertilization procedures. Fertil Steril 1999; 72:702-6. [PMID: 10521114 DOI: 10.1016/s0015-0282(99)00309-x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To assess the technique of injecting a single sperm and cytoplasm obtained from tripronucleate zygotes into metaphase II oocytes for the treatment of patients with repeated implantation failure after intracytoplasmic sperm injection or IVF. DESIGN Clinical study. SETTING Private infertility clinic. PATIENT(S) Patients with repeated implantation failure after intracytoplasmic sperm injection or IVF. INTERVENTION(S) The metaphase II oocytes of recipients were injected with their husbands' spermatozoa and cytoplasm aspirated from the tripronucleate zygotes of donors. MAIN OUTCOME MEASURE(S) Fertilization after cytoplasm and sperm injection, embryo development, and successful pregnancy. RESULT(S) In total, 62 metaphase II oocytes from nine recipients were injected. Of the 62 injected oocytes, 3 (5%) degenerated and 43 (69%) had two pronuclei 18 hours after injection. Thirty-nine oocytes with two pronuclei cleaved to the two-cell to six-cell stage after another 24 hours of culture. All cleaved embryos were transferred into the uteruses of recipients. Four clinical pregnancies occurred in four recipients. No abnormal chromosomes were observed after amniocentesis and karyotyping in all pregnancies. Five healthy infants were born. CONCLUSION(S) Injection of the cytoplasm of tripronucleate zygotes may enhance the clinical pregnancy rate in patients with repeated implantation failure after intracytoplasmic sperm injection or IVF.
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Affiliation(s)
- C C Huang
- Infertility Clinic, Lee Women's Hospital, Taichung, Taiwan, Republic of China
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Abstract
Enzymes catalyzing the hydrolysis of highly toxic organophosphorus compounds (OPs) are classified as organophosphorus acid anhydrolases (OPAA; EC 3.1.8.2). Recently, the genes encoding OPAA from two species of Alteromonas were cloned and sequenced. Sequence and biochemical analyses of the cloned genes and enzymes have established Alteromonas OPAAs to be prolidases (E.C. 3.4.13.9), a type of dipeptidase hydrolyzing dipeptides with a prolyl residue in the carboxyl-terminal position (X-Pro). Alteromonas prolidases hydrolyze a broad range of G-type chemical warfare (CW) nerve agents. Efforts to over-produce a prolidase from A. sp.JD6.5 with the goal of developing strategies for long-term storage and decontamination have been successfully achieved. Large-scale production of this G-agent degrading enzyme is now feasible with the availability of an over-producing recombinant cell line. Use of this enzyme for development of a safe and non-corrosive decontamination system is discussed.
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Affiliation(s)
- T C Cheng
- Environmental Technology Team, US Army Edgewood Research, Development and Engineering Center, Aberdeen, MD 21010, USA.
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Affiliation(s)
- T C Cheng
- United States Army Edgewood Research, Development, and Engineering Center, Aberdeen Proving Ground, Maryland 21010, USA
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35
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Affiliation(s)
- J H Chang
- Department of Urology, National Cheng-Kung University Hospital, Tainan, Taiwan, ROC
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36
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Abstract
The Russian-VX (R-VX) is the principle V-type nerve agent in the chemical warfare (CW) arsenal of the Former Soviet Union. We here report the enzymatic hydrolysis of the P-S bond of Russian-VX by organophosphorus hydrolase (OPH) from Pseudomonas diminuta. While the Michaelis constant, K(m) for R-VX (474 microM), was similar to that for VX (434 microM), the Vmax for R-VX (2.1 mumoles/mg/min) was about four-fold higher compared to that for VX (0.56 mumoles/mg/min). A 50% inhibition in the rate of the enzymatic hydrolysis of R-VX was observed in the presence of 0.5% ethanol, isoamyl-alcohol, or isopropanol. The presence of acetonitrile, diethylene glycol, or methanol had marginal effects. These results comprise the first demonstration of enzymatic detoxification of R-VX.
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Affiliation(s)
- V K Rastogi
- GEO-Centers, Inc./ERDEC, Aberdeen Proving Ground, Maryland 21010, USA.
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Chang CP, Liu RS, Yu SM, Wynchank S, Chu LS, Shiau HY, Cheng TC. Clinical evaluation of the bone marrow imaging agent 99Tcm-phytate in the detection of bone metastases. Nucl Med Commun 1996; 17:1030-4. [PMID: 9004298 DOI: 10.1097/00006231-199612000-00005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The aims of this study were to assess whether 99Tcm-phytate can detect metastatic skeletal lesions, and to compare it with 99Tcm-methylene diphosphonate (99Tcm-MDP) and 99Tcm-labelled human serum albumin nanocolloids (99Tcm-NC). Twenty-four patients with multiple bony metastases, investigated by 99Tcm-MDP whole-body scintigraphy, underwent 99Tcm-phytate bone marrow imaging. A separate bone marrow scintigram with 99Tcm-NC was performed in 20 of the patients. All of the metastatic lesions detected on the 99Tcm-phytate scintigrams exhibited photon-abundant foci only. Most of the 99Tcm-phytate scintigrams detected fewer metastatic lesions than the corresponding bone scintigrams. Visual comparison of the 99Tcm-NC images showed that 13 of 20 99Tcm-NC images were superior to the 99Tcm-phytate images in the detection of metastatic involvement of the skeleton. Thus 99Tcm-phytate should not be used as a bone marrow imaging agent for the detection of skeletal metastases.
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Affiliation(s)
- C P Chang
- Department of Nuclear Medicine, Taipei Veterans General Hospital, National Defense Medical Center, Taiwan, Republic of China
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38
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Abstract
Crocetin, a carotenoid isolated from the seeds of Gardenia jasminoides, was found to be a potent inhibitor of tumor promotion induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in mouse skin. When mouse fibroblast NIH/3T3 cells were treated with TPA alone, protein kinase C (PKC) translocated from the cytosolic fraction to the particulate fraction. Pretreatment with 60 and 120 microM crocetin for 15 min inhibited the TPA-induced PKC activity in the particulate fraction by 50% and 66%, respectively, but did not affect the level of PKC protein. Crocetin also reduced the level of TPA-stimulated phosphorylation of cellular proteins. Cells pretreated with crocetin (120 microM) had 55% less PKC [3H]phorbol dibutyrate-binding capacity. Suppression of TPA (100 ng/mL)-induced c-jun and c-fos gene expression was also observed in the mouse fibroblast cells pretreated with crocetin (30, 60, and 120 microM). Our results provided a basis for understanding the inhibitory effect of crocetin on TPA-mediated tumor promotion.
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Affiliation(s)
- C J Wang
- Institute of Biochemistry, Chung Shan Medical and Dental College, Taichung, Taiwan, Republic of China
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39
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Benton HP, Cheng TC, MacDonald MH. Use of adverse conditions to stimulate a cellular stress response by equine articular chondrocytes. Am J Vet Res 1996; 57:860-5. [PMID: 8725814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
OBJECTIVE To determine the response of equine articular cartilage cells to heat and calcium stresses. DESIGN Analysis of newly synthesized, [35S]methionine-labeled proteins after treatment of isolated primary equine chondrocytes. PROCEDURE Primary cultures of equine articular chondrocytes were incubated at temperatures ranging from 37 to 42 C for heat stress experiments or incubated in the presence or absence of the intracellular calcium pump inhibitor, thapsigargin, for calcium stress experiments. Patterns of new protein synthesis were determined by incubating with [35S]methionine followed by separation of proteins by use of one- or two-dimensional gel electrophoresis and visualization of labeled proteins by use of fluorography. RESULTS Equine chondrocytes cultured at temperature of 42 C had increased synthesis of specific proteins, compared with the profile of protein synthesis in control chondrocytes cultured at 37 C. These changes were characteristic of the heat shock stress response described in a number of other mammalian cell-types. Equine chondrocytes cultured in the presence of thapsigargin also had increased synthesis of specific proteins. Two-dimensional gel electrophoresis of these newly synthesized proteins revealed the changes to be consistent with the induction of the glucose-regulated protein family of stress proteins. CONCLUSIONS Changes in the pattern of new protein synthesis can be induced in differentiated equine articular chondrocytes by heat shock or calcium stress. These responses are characteristic of a widely described mammalian stress response that has been postulated to be involved in cellular protective mechanisms. The ability of equine chondrocytes to mount a robust stress response may be important in the processes of tissue damage and recovery in articular joints of horses.
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Affiliation(s)
- H P Benton
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California, Davis 95616, USA
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40
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Cheng TC, Harvey SP, Chen GL. Cloning and expression of a gene encoding a bacterial enzyme for decontamination of organophosphorus nerve agents and nucleotide sequence of the enzyme. Appl Environ Microbiol 1996; 62:1636-41. [PMID: 8633861 PMCID: PMC167937 DOI: 10.1128/aem.62.5.1636-1641.1996] [Citation(s) in RCA: 104] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Organophosphorus acid (OPA) anhydrolase enzymes have been found in a wide variety of prokaryotic and eukaryotic organisms. Interest in these enzymes has been prompted by their ability to catalyze the hydrolysis of toxic organophosphorus cholinesterase-inhibiting compounds, including pesticides and chemical nerve agents. The natural substrates for these enzymes are unknown. The gene (opaA) which encodes an OPA anhydrolase (OPAA-2) was isolated from an Alteromonas sp. strain JD6.5 EcoRI-lambda ZAPII chromosomal library expressed in Escherichia coli and identified by immunodetection with anti-OPAA-2 serum. OPA anhydrolase activity expressed by the immunopositive recombinant clones was demonstrated by using diisopropylfluorophosphate (DFP) as a substrate. A comparison of the recombinant enzyme with native, purified OPAA-2 showed they had the same apparent molecular mass (60 kDa), antigenic properties, and enzyme activity against DFP and the chemical nerve agents sarin, soman, and O-cyclohexyl methylphosphonofluoridate. The gene expressing this activity was found in a 1.74-kb PstI-HindIII fragment of the original 6.1-kb EcoRI DNA insert. The nucleotide sequence of this PstI-HindIII fragment revealed an open reading frame of 1,551 nucleotides, coding for a protein of 517 amino acid residues. Amino acid sequence comparison of OPAA-2 with the protein database showed that OPAA-2 is similar to a 647-amino-acid sequence produced by an open reading frame which appears to be the E. coli pepQ gene. Further comparison of OPAA-2, the E. coli PepQ protein sequence, E. coli aminopeptidase P, and human prolidase showed regions of different degrees of similarity or functionally conserved amino acid substitutions. These findings, along with preliminary data confirming the presence of prolidase activity expressed by OPAA-2, suggest that the OPAA-2 enzyme may, in nature, be used in peptide metabolism.
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Affiliation(s)
- T C Cheng
- U.S. Army Edgewood Research, Development and Engineering Center, Research and Technology Directorate, Aberdeen Proving Ground, Maryland 21010, USA.
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41
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Yu H, Bruno JG, Cheng TC, Calomiris JJ, Goode MT, Gatto-Menking DL. A comparative study of PCR product detection and quantitation by electro-chemiluminescence and fluorescence. J Biolumin Chemilumin 1995; 10:239-45. [PMID: 8533605 DOI: 10.1002/bio.1170100407] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Amplification and detection of target DNA sequences are made possible in a polymerase chain reaction (PCR) by using a mixture of biotinylated and ruthenium(II) trisbipyridal (Ru(bpy)3(2+))-end-labelled primers. In this way, biotin for capture and Ru(bpy)3(2+) for detection are directly incorporated into the PCR product obviating subsequent probe hybridization. PCR of a bacterial DNA template from Alteromonas species strain JD6.5 using a cocktail of biotin- and Ru(bpy)3(2+)-labelled primers amplified a 1 kilobase region. Serial dilution of PCR product followed by magnetic separation with Streptavidin (SA)-coated magnetic beads and an electrochemiluminescence (ECL) assay using the semi-automated QPCR System 5000 demonstrated sensitive (pg range) DNA detection. ECL assay of probe hybridization to a human immunodeficiency virus (HIV) sequence also produced pg level sensitivity. Quantitative DNA determination by ECL assay correlated well with visual detection of DNA in electrophoretic gels. However, DNA detection by ECL assay was 10 to 100 times more sensitive than conventional ethidium bromide staining. The combination of DNA-based magnetic separation with ECL assay provides a very sensitive and rapid method of quantitating DNA which, owing to its rapid and facile nature, may have many applications in the research, environmental monitoring, industrial and clinical fields.
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Affiliation(s)
- H Yu
- Optech Corporation, San Antonio, TX 78229, USA
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42
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Cheng TC, Tsai TC, Lin GJ. Successful medical treatment for staphylococcal vertebral osteomyelitis complicated by spinal epidural abscess, psoas abscess and meningitis: a case report. Gaoxiong Yi Xue Ke Xue Za Zhi 1995; 11:295-9. [PMID: 7602668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A 42 year-old farmer was transferred to our hospital for recently exaggerated lower back pain. Neurological examination revealed an L4 radiculopathy on the right side. Meningitis developed after admission. MRI showed L4-5 osteomyelitis and discitis with contiguous spinal epidural abscess and right psoas abscess. Blood culture and CSF culture both grew Staphylococcus aureus. Because the patient refused to receive a drainage procedure, we gave him antibiotics which resulted in a favorable outcome.
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Affiliation(s)
- T C Cheng
- Department of Urology, Chi-Mei Foundation Hospital, Taiwan, Republic of China
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43
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Cheng TC, Tseng BS, Merlie JP, Klein WH, Olson EN. Activation of the myogenin promoter during mouse embryogenesis in the absence of positive autoregulation. Proc Natl Acad Sci U S A 1995; 92:561-5. [PMID: 7831329 PMCID: PMC42781 DOI: 10.1073/pnas.92.2.561] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Myogenin, a member of the MyoD family of helix-loop-helix proteins, can induce myogenesis in a wide range of cell types. In addition to activating muscle structural genes, members of the MyoD family can autoactivate their own and cross-activate one another's expression in transfected cells. This has led to the hypothesis that autoregulatory loops among these factors provide a mechanism for amplifying and maintaining the muscle-specific gene expression program in vivo. Here, we make use of myogenin-null mice to directly test this hypothesis. To investigate whether the myogenin protein autoregulates the myogenin gene during embryogenesis, we introduced a myogenin-lacZ transgene into mice harboring a null mutation at the myogenin locus. Despite a severe deficiency of skeletal muscle in myogenin-null neonates, the myogenin-lacZ transgene was expressed normally in myogenic cells throughout embryogenesis. These results show that myogenin is not required for regulation of the myogenin gene and argue against the existence of a myogenin autoregulatory loop in the embryo.
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Affiliation(s)
- T C Cheng
- Department of Biochemistry and Molecular Biology, University of Texas M.D. Anderson Cancer Center, Houston 77030
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44
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Cheng TC, Benton HP. The intracellular Ca(2+)-pump inhibitors thapsigargin and cyclopiazonic acid induce stress proteins in mammalian chondrocytes. Biochem J 1994; 301 ( Pt 2):563-8. [PMID: 8043004 PMCID: PMC1137118 DOI: 10.1042/bj3010563] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Primary cultures of mammalian articular chondrocytes respond to treatment with the intracellular Ca(2+)-pump inhibitors thapsigargin (TG) and cyclopiazonic acid by specific changes in protein synthesis consistent with a stress response. Two-dimensional gel electrophoresis of newly synthesized proteins confirmed that the response was consistent with the induction of glucose-regulated proteins. The effects of low-dose TG (10 nM), measured by changes in [35S]methionine labelling of newly synthesized proteins, can first be observed by 10 h and are maximal by 24 h. The pattern of changes induced by TG is shared with cyclopiazonic acid, but effects of both perturbants differ significantly from changes induced by heat shock. Upon removal of TG, normal protein synthesis is restored by 48 h. Immunoblots showed increased concentrations of the stress proteins HSP90, HSP72/73 and HSP60 in chondrocytes treated with TG, but induction of newly synthesized heat-shock proteins by TG was not apparent on [35S]methionine-labelled gels. The alterations in protein synthesis induced by Ca(2+)-pump inhibitors were unaffected by BAPTA-AM loading, which clamped cytosolic Ca2+ at resting levels. We conclude that inhibition of intracellular Ca(2+)-pump activity can elicit a stress response, which has important implications for the interpretation of chronic use of Ca(2+)-pump inhibitors. In particular, the activation of the cellular shock response should be considered in interpreting the regulation of protein synthesis and cell survival by Ca(2+)-pump inhibitors such as TG.
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Affiliation(s)
- T C Cheng
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis 95616
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45
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Merlie JP, Mudd J, Cheng TC, Olson EN. Myogenin and acetylcholine receptor alpha gene promoters mediate transcriptional regulation in response to motor innervation. J Biol Chem 1994; 269:2461-7. [PMID: 8300573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Several genes expressed in skeletal muscle are transcriptionally repressed by electrical activity arising from motor innervation and are rapidly induced following denervation. Among these are genes encoding the subunits of the nicotinic acetylcholine receptor (AChR) and the myogenic helix-loop-helix protein myogenin, which activates muscle-specific genes. To understand how electrical activity arising from motor innervation is converted into a transcriptional response, we have attempted to localize cis-acting sequences in the AChR alpha subunit and myogenin genes sufficient to direct activity-dependent transcription. Here we show that an 111-base pair and a 335-base pair region from the promoters of the AChR alpha subunit and myogenin genes, respectively, can confer activity-dependent regulation to a linked reporter gene in transgenic mice. The presence of binding sites for myogenic helix-loop-helix proteins in both of these regulatory regions is consistent with the hypothesis that these myogenic regulators serve as nuclear targets for the signaling cascade through which motor innervation leads to changes in gene transcription in skeletal muscle.
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Affiliation(s)
- J P Merlie
- Department of Molecular Biology and Pharmacology, Washington University School of Medicine, St. Louis, Missouri 63110
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46
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Leibham D, Wong MW, Cheng TC, Schroeder S, Weil PA, Olson EN, Perry M. Binding of TFIID and MEF2 to the TATA element activates transcription of the Xenopus MyoDa promoter. Mol Cell Biol 1994; 14:686-99. [PMID: 8264638 PMCID: PMC358418 DOI: 10.1128/mcb.14.1.686-699.1994] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Members of the MyoD family of helix-loop-helix proteins control expression of the muscle phenotype by regulating the activity of subordinate genes. To investigate processes that control the expression of myogenic factors and regulate the establishment and maintenance of the skeletal muscle phenotype, we have analyzed sequences necessary for transcription of the maternally expressed Xenopus MyoD (XMyoD) gene. A 3.5-kb DNA fragment containing the XMyoDa promoter was expressed in a somite-specific manner in injected frog embryos. The XMyoDa promoter was active in oocytes and cultured muscle cells but not in fibroblasts or nonmuscle cell lines. A 58-bp fragment containing the transcription initiation site, a GC-rich region, and overlapping binding sites for the general transcription factor TFIID and the muscle-specific factor MEF2 was sufficient for muscle-specific transcription. Transcription of the minimal XMyoDa promoter in nonmuscle cells was activated by expression of Xenopus MEF2 (XMEF2) and required binding of both MEF2 and TFIID to the TATA motif. These results demonstrate that the XMyoDa TATA motif is a target for a cell-type-specific regulatory factor and suggests that MEF2 stabilizes and amplifies XMyoDa transcription in mesodermal cells committed to the muscle phenotype.
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Affiliation(s)
- D Leibham
- Department of Biochemistry and Molecular Biology, University of Texas M. D. Anderson Cancer Center, Houston 77030
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Cheng TC, Harvey SP, Stroup AN. Purification and Properties of a Highly Active Organophosphorus Acid Anhydrolase from
Alteromonas undina. Appl Environ Microbiol 1993; 59:3138-40. [PMID: 16349054 PMCID: PMC182420 DOI: 10.1128/aem.59.9.3138-3140.1993] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A highly active organophosphorus acid anhydrolase from
Alteromonas undina
was purified to homogeneity and found to be composed of a single polypeptide chain with a molecular weight of 53,000. With diisopropylfluorophosphate as a substrate, the purified enzyme has a specific activity of ∼575 μmol/min/mg of protein. The enzyme has optimum activity at pH 8.0 and 55�C and is stimulated by sulfhydryl reducing agents and manganese. It is capable of rapidly hydrolyzing a wide range of nerve agents and several chromogenic phosphinates.
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Affiliation(s)
- T C Cheng
- U.S. Army Chemical and Biological Defense Agency, Edgewood Research, Development and Engineering Center, Research and Technology Directorate, Aberdeen Proving Ground, Maryland 21010-5423
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Abstract
Expression of the myogenic helix-loop-helix (HLH) protein myogenin in muscle cell precursors within somites and limb buds is among the earliest events associated with myogenic lineage determination in vertebrates. Mutations in the myogenin promoter that abolish binding sites for myogenic HLH proteins or myocyte enhancer factor-2 (MEF-2) suppressed transcription of a linked lacZ transgene in subsets of myogenic precursors in mouse embryos. These results suggest that myogenic HLH proteins and MEF-2 participate in separable regulatory circuits leading to myogenin transcription and provide evidence for positional regulation of myogenic regulators in the embryo.
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Affiliation(s)
- T C Cheng
- Department of Biochemistry and Molecular Biology, University of Texas M.D. Anderson Cancer Center, Houston 77030
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DeFrank JJ, Beaudry WT, Cheng TC, Harvey SP, Stroup AN, Szafraniec LL. Screening of halophilic bacteria and Alteromonas species for organophosphorus hydrolyzing enzyme activity. Chem Biol Interact 1993; 87:141-8. [PMID: 8393735 DOI: 10.1016/0009-2797(93)90035-w] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Previously, a G-type nerve agent degrading enzyme activity was found in a halophilic bacterial isolate designated JD6.5. This organism was tentatively identified as an unknown species of the genus Alteromonas. In order to determine whether this type of enzyme activity was common in other species of Alteromonas, a screening program was initiated. A number of Alteromonas species and five halophilic bacterial isolates were cultured and their crude cell extracts screened for hydrolytic activity against several organophosphorus chemical agents and other related compounds. The samples were also screened for cross-reactivity with a monoclonal antibody raised against the purified enzyme from JD6.5 and for hybridization with a DNA probe based on its N-terminal amino acid sequence A wide spectrum of activities and reactivities were seen, suggesting a significant heterogeneity between the functionally similar enzymes that are present in these bacterial species. Enzymes of the type described here have considerable potential for the decontamination and demilitarization of chemical warfare agents.
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Affiliation(s)
- J J DeFrank
- Biochemical Decontamination Team, U.S. Army Edgewood Research, Development and Engineering Center, Aberdeen Proving Ground, MD 21010-5423
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Cheng TC, Hanley TA, Mudd J, Merlie JP, Olson EN. Mapping of myogenin transcription during embryogenesis using transgenes linked to the myogenin control region. J Biophys Biochem Cytol 1992; 119:1649-56. [PMID: 1334962 PMCID: PMC2289748 DOI: 10.1083/jcb.119.6.1649] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
During vertebrate embryogenesis, the muscle-specific helix-loop-helix protein myogenin is expressed in muscle cell precursors in the developing somite myotome and limb bud before muscle fiber formation and is further upregulated during myogenesis. We show that cis-acting DNA sequences within the 5' flanking region of the mouse myogenin gene are sufficient to direct appropriate temporal, spatial, and tissue-specific transcription of myogenin during mouse embryogenesis. Myogenin-lacZ transgenes trace the fate of embryonic cells that activate myogenin transcription and suggest that myogenic precursor cells that migrate from the somite myotome to the limb bud are committed to a myogenic fate in the absence of myogenin transcription. Activation of a myogenin-lacZ transgene can occur in limb bud explants in culture, indicating that signals required for activation of myogenin transcription are intrinsic to the limb bud and independent of other parts of the embryo. These results reveal multiple populations of myogenic precursor cells during development and suggest the existence of regulators other than myogenic helix-loop-helix proteins that maintain cells in the early limb bud in the myogenic lineage.
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Affiliation(s)
- T C Cheng
- Department of Biochemistry and Molecular Biology, University of Texas M. D. Anderson Cancer Center, Houston 77030
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