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Liao YF, Chen LL, Zeng TS, Zheng J, Li HQ. Association of the +33371 A/G polymorphism in adiponectin receptor 2 gene with Type 2 diabetes in the Chinese population. J Endocrinol Invest 2007; 30:860-4. [PMID: 18075289 DOI: 10.1007/bf03349228] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE The aim of this study was to investigate the association between the +33371 A/G polymorphism of adiponectin receptor 2 gene and the risk of Type 2 diabetes (T2DM) in the Chinese population. METHODS A case-control study was performed among 594 unrelated Chinese people. All of them underwent a standardized assessment on phenotypic characterization including anthropometry, 75-g oral glucose tolerance test with insulin levels, fasting serum total cholesterol, and fasting serum triglyceride. The +33371 A/G polymorphism was detected by PCR-restriction fragment length polymorphism. RESULTS The PCR products after digestion displayed 3 genotypes, including AA, AG, and GG. The frequencies of AA, AG, and GG genotypes in T2DM group (no.=261) and control group (no.=353) were 0.379, 0.414, 0.207 and 0.162, 0.541, 0.297, respectively. There was a significant difference in both genotypic and allelic frequencies distribution of +33371 A/G polymorphism between T2DM and control subjects (p<0.001). Subjects with AA+AG genotypes showed higher levels of fasting plasma glucose (p=0.024), fasting serum triglycerides (p=0.036), and body mass index (BMI) (p=0.013) than those with GG genotype in the T2DM group but not in the control group. Compared with GG genotype, AA (p<0.001) and AA+AG (p=0.002) genotype group had a significantly higher risk of T2DM, with odds ratio (OR) for 2.290 [95% confidence interval: 1.482-3.359] and 1.963 (1.183-2.997). Compared with AG+GG genotype group, the risk of T2DM in AA genotype increased slightly (p=0.007), with OR for 1.478 (1.025-2.036). CONCLUSION The present findings suggest that +33371 A/G polymorphism is associated with increased risk of T2DM and multiple insulin resistance-related phenotypes (including fasting plasma glucose, fasting serum triglycerides, and BMI) in the Chinese population.
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Affiliation(s)
- Y F Liao
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
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Zhang J, Wu YO, Xiao L, Li K, Chen LL, Sirois P. Therapeutic potential of RNA interference against cellular targets of HIV infection. Mol Biotechnol 2007; 37:225-36. [PMID: 17952669 PMCID: PMC7091338 DOI: 10.1007/s12033-007-9000-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2007] [Accepted: 08/09/2007] [Indexed: 12/11/2022]
Abstract
RNA interference is not only very promising in identifying new targets for drug development, siRNA/shRNA themselves may be directly used as therapeutic agents. In inhibiting viral infections by RNA interference, both viral targets and cellular proteins have been evaluated. Most of the early studies in this field had chosen viral targets for RNA interference. However, recent efforts are mainly focusing on cellular proteins for RNA silencing due to the realization that a variety of viral responses substantially minimize siRNA effects. With the application of siRNA approaching, many new cellular targets relevant to HIV infection have been identified. The value of siRNA/shRNA in the treatment of AIDS is largely dependent on better understanding of the biology of HIV replication. Efforts in the identification of cellular processes with the employment of siRNA/shRNA have shed some new lights on our understanding of how HIV infection occurs. Furthermore, the relative specific effects and simplicity of design makes siRNA/shRNA themselves to be favorable drug leads.
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Affiliation(s)
- Jia Zhang
- Gene Core, The Genomics Institute of the Novartis Research Foundation, San Diego, CA, USA
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Hong RY, Chen LL, Li JH, Li HZ, Zheng Y, Ding J. Preparation and application of polystyrene-grafted ZnO nanoparticles. POLYM ADVAN TECHNOL 2007. [DOI: 10.1002/pat.926] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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104
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Chen XJ, Zheng W, Chen LL, Chen ZB, Wang SQ. Telomerase antisense inhibition for the proliferation of endometrial cancer in vitro and in vivo. Int J Gynecol Cancer 2006; 16:1987-93. [PMID: 17177836 DOI: 10.1111/j.1525-1438.2006.00734.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [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: 11/30/2022] Open
Abstract
The objective of this study was to investigate the antitumor effect of antisense telomerase oligodeoxynucleotides to endometrial cancer cells in vitro and in vivo. Antisense oligodeoxynucleotides (ODNs) against the human telomerase transcripatse (hTERT) synthesized to serve as telomerase inhibitors. Reverse transcription–polymerase chain reaction and 3-[4,5-dimethylthiazol-2yl]-2,5-diphenyltetrazolium bromide (MTT) assay were used to test the expression of hTERT messengerRNA (mRNA) and inhibition of cell proliferation in vitro. In vivo, antitumor effects of ODNs or combined with cisplatin were evaluated in endometrial cancer xenograft. Telomerase activity was tested by telomeric repeat amplification protocol. Antisense ODNs could inhibit proliferation of human endometrial cancer cells (HEC-1-A) in vitro, and downregulate the expression hTRET mRNA in a dose- and period-dependent manner. The tumor growth inhibitory rate of low- and high-dose ODNs were 34.20% and 89.21%, and combined group was 75.30%. Telomerase activity was downregulated to 87.32% compared to the control in the ODNs-treated xenograft tumors. Antisense oligonucleotides of hTERT effectively inhibit the growth of endometrial cancer cell line. Telomerase inhibitor might be a new strategy for chemotherapy or chemoprevention in endometrial cancer.
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Affiliation(s)
- X J Chen
- Second Hospital of Zhejiang University School of Medicine, Hangzhou, China
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105
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Benjamin RS, Choi H, Macapinlac HA, Burgess MA, Patel SR, Chen LL, Podoloff DA, Chuslip C. Response of gastrointestinal stromal tumors (GISTs) to imatinib by Choi criteria and response evaluation criteria in solid tumors (RECIST) as surrogates for survival and time to progression. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.9506] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [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
9506 Background: Recent studies have demonstrated that RECIST is insensitive in evaluating GIST’s treated with imatinib. We have demonstrated in a small group of patients that a good response by Choi Criteria, i.e., a 10% decrease in unidimensional tumor size or a 15% decrease in tumor density on contrast-enhanced CT, correlated well with good response by PET (Proc. ASCO 22:819, 2003) and was more predictive of time to tumor progression (TTP) than response by RECIST (CTOS 2004). The aim of this study was to validate the correlation with disease-specific survival (DSS) and TTP with follow-up updated to 5-years. Methods: We evaluated 98 patients treated with imatinib for recurrent or metastatic GIST at our institution from December 2000 to September 2001 by RECIST and Choi criteria. All patients had pre-treatment and initial 2-monthly follow-up CT’s. DSS and TTP were analyzed by response category. Results: There were 28 (48%) good responders by RECIST and 30 (52%) poor responders. There were 49 (84%) good responders by Choi criteria, and 9 (16%) poor responders. Patients with good response by Choi criteria on CT at 8 weeks after treatment had significantly improved DSS (P = 0.04) in contrast to those with complete or partial response at any time by RECIST (P = 0.45). Similarly, TTP was significantly correlated with Choi response group (P = 0.01) but not with response group by RECIST (P = 0.74). Conclusions: Choi response criteria, incorporating tumor density and using small changes in tumor size on CT, are more sensitive and more accurate than RECIST in assessing the response of GISTs to imatinib mesylate and should be routinely incorporated into future studies of GIST therapy. Good response is detected earlier by Choi criteria and is a valid surrogate for DSS and TTP. We should desist using RECIST, at least in GIST. (Supported in part by NCI contracts U01-CA70172–01 and N01-CM-17003) [Table: see text]
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Affiliation(s)
| | - H. Choi
- UT M. D. Anderson Cancer Center, Houston, TX
| | | | | | - S. R. Patel
- UT M. D. Anderson Cancer Center, Houston, TX
| | - L. L. Chen
- UT M. D. Anderson Cancer Center, Houston, TX
| | | | - C. Chuslip
- UT M. D. Anderson Cancer Center, Houston, TX
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Chen LL, Prieto VG, Sabripour M, Wu EF, Raymond AK, Sang H, Frazier ML. Loss of heterozygosity with acquisition of homozygous KIT-activating mutation promotes gastrointestinal stromal tumor progression. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.9530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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
9530 Background: Gastrointestinal stromal tumors (GISTs) originate from interstitial cells of Cajal and represent the most common mesenchymal tumor of GI tract. The activating mutations of KIT and platelet-derived growth factor receptor α (PDGFRA) have been demonstrated in 88% and 6% of GISTs respectively. Multiple genetic events are involved in tumor initiation and progression. Activation of an oncogene can result from a single hit of gain-of-function mutation, but two hits leading to loss of heterozygosity (LOH) are necessary for inactivation of a tumor suppressor gene for the initiation of neoplasia. Little is known about the significance and mechanism of LOH of oncogenes in tumor progression. The LOH of activating-oncogenes is not infrequent, i.e. in more than 8% of GIST. These GIST clones with LOH prevail and dominate, strongly suggestive of proliferative and metastatic advantages. However, the significance and mechanisms of LOH acquiring homozygous activating-oncogene mutation remain unknown. Methods: Genomic DNA and cDNA sequencing analysis of KIT, single-nucleotide polymorphisms (SNPs), immunohistochemistry of GISTs clones, and 3D structural analysis of the mutated KIT. Results: Real-time genetic studies in GIST show initial development of overexpression of KIT without mutation, to coexistence of various heterozygous-activating mutations; eventually, one clone dominates. Comparisons within the same patient show that clonal evolution from heterozygous to LOH acquiring homozygous (diploid) KIT-activating mutation results in dominance of the latter, with augmented KIT signaling and doubling of mitotic figures. Using SNPs for allelotyping, we found that mitotic nondisjunction, rather than mitotic recombination, represents an important mechanism of the second hit. Conclusion: GIST clones with LOH acquiring homozygous KIT-activating mutation gain a selective advantage over the heterozygous counterpart. Mitotic nondisjunction, in addition to the commonly recognized mitotic recombination, is an important and perhaps the primary mechanism of LOH acquiring homozygous KIT-activating mutation during GIST progression. No significant financial relationships to disclose.
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Affiliation(s)
- L. L. Chen
- M. D. Anderson Cancer Center, Houston, TX; University of Alabama at Birmingham, Birmingham, AL; Xijing Hospital, Fourth Medical University, Xi’an City, China
| | - V. G. Prieto
- M. D. Anderson Cancer Center, Houston, TX; University of Alabama at Birmingham, Birmingham, AL; Xijing Hospital, Fourth Medical University, Xi’an City, China
| | - M. Sabripour
- M. D. Anderson Cancer Center, Houston, TX; University of Alabama at Birmingham, Birmingham, AL; Xijing Hospital, Fourth Medical University, Xi’an City, China
| | - E. F. Wu
- M. D. Anderson Cancer Center, Houston, TX; University of Alabama at Birmingham, Birmingham, AL; Xijing Hospital, Fourth Medical University, Xi’an City, China
| | - A. K. Raymond
- M. D. Anderson Cancer Center, Houston, TX; University of Alabama at Birmingham, Birmingham, AL; Xijing Hospital, Fourth Medical University, Xi’an City, China
| | - H. Sang
- M. D. Anderson Cancer Center, Houston, TX; University of Alabama at Birmingham, Birmingham, AL; Xijing Hospital, Fourth Medical University, Xi’an City, China
| | - M. L. Frazier
- M. D. Anderson Cancer Center, Houston, TX; University of Alabama at Birmingham, Birmingham, AL; Xijing Hospital, Fourth Medical University, Xi’an City, China
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Kleinbaum EP, Chen LL, Lazar A, Strong L, Zhang W, Choi H, Benjamin R, Patel S, Trent JC. Familial gastrointestinal stromal tumor with homo-/hemizygous kit exon 11 deletion: Genotypic, histopathologic, radiographic, and therapeutic findings. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.9527] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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
9527 Background: Germ-line mutations in the kit receptor tyrosine kinase gene have been described in families with a propensity to develop gastrointestinal stromal tumor (GIST). We describe a large kindred with multiple individuals with GIST and describe the genotype, clinical presentation, radiographic imaging, surgical findings, imatinib-sensitivity, and histopathologic appearance. Patients and Methods: A large kindred with multiple GISTs were identified after the proband patient was referred to our institution. The history of each affected and unaffected family member was obtained in person or via telephone. A medical questionnaire was sent to family members and appropriate medical records, tumor tissue and radiographic imaging was obtained. Histopathologic specimens from four of the family members with GIST was obtained, the diagnosis confirmed and three specimens were used to sequence kit exon 9, 11, 13, 15 and 17. Results: Fifteen members were identified in this family with histopathologic diagnosis of GIST or probable GIST. Surgical findings revealed multiple tumors arising from the submucosa of the small intestine. Histopathology revealed microscopic proliferation of the myenteric plexus with areas of microscopic tumor nodularity. Four patients in this kindred were treated with imatinib and had radiographic and clinical evidence of therapeutic benefit. A deletion of codon 579 in exon 11 of the kit gene was identified in tumor and normal tissue of this family. Evaluation of one GIST revealed loss of heterozygosity in kit exon 11 suggesting a homozygous mutation or loss of the wild-type locus. Conclusion: This study describes a kindred with a propensity to develop GIST in association with hyperpigmentation and melanocytic nevi, but not dysphagia. The germline deletion of codon 579 appears to confer proliferation and nodularity of the myenteric plexus, synchronous tumors at presentation, a metastatic phenotype, and in vivo sensitivivity to imatinib therapy. No significant financial relationships to disclose.
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Affiliation(s)
- E. P. Kleinbaum
- Baylor College of Medicine, Houston, TX; M. D. Anderson Cancer Center, Houston, TX
| | - L. L. Chen
- Baylor College of Medicine, Houston, TX; M. D. Anderson Cancer Center, Houston, TX
| | - A. Lazar
- Baylor College of Medicine, Houston, TX; M. D. Anderson Cancer Center, Houston, TX
| | - L. Strong
- Baylor College of Medicine, Houston, TX; M. D. Anderson Cancer Center, Houston, TX
| | - W. Zhang
- Baylor College of Medicine, Houston, TX; M. D. Anderson Cancer Center, Houston, TX
| | - H. Choi
- Baylor College of Medicine, Houston, TX; M. D. Anderson Cancer Center, Houston, TX
| | - R. Benjamin
- Baylor College of Medicine, Houston, TX; M. D. Anderson Cancer Center, Houston, TX
| | - S. Patel
- Baylor College of Medicine, Houston, TX; M. D. Anderson Cancer Center, Houston, TX
| | - J. C. Trent
- Baylor College of Medicine, Houston, TX; M. D. Anderson Cancer Center, Houston, TX
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108
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Lin EH, Li Y, Trent J, Patel SM, Burgess MA, Steinert DM, Benjamin RS, Li D, Chen LL. Quantitative real time-PCR of CD133 mRNA: A potential surrogate angiogenic marker of response for patients with metastatic sarcoma. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.20034] [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: 11/20/2022] Open
Abstract
20034 Background: CD133 antigen is a specific surface marker for circulating endothelial progenitor cells (CEPs), pivotal in post-natal angiogenesis. We hypothesize that changes in levels of the CD133 mRNA expression and vascular endothelial growth factor (VEGF) may correlate with tumor response. Methods: After informed consent, we obtained 48 peripheral blood samples from patients with metastatic sarcoma including gastrointestinal stroma tumors (GIST). There were 16-paired samples before and after treatment including chemotherapy, or surgery, or imatinib. Of 24 patients with metastatic GIST enrolled, seven were paired samples. We measured CD133 mRNA levels by method (Lin E et al AACR 2003# 5392) and VEGF levels by ELISA (Genzyme, MA). The measurements were done in duplicates in two experiments. Results: The mean CD133 levels and VEGF levels before and after treatment was in Table 1 . The treatment resulted in significant reduction of CD133 mRNA expression (p = 0.035) as well as the level of VEGF (p = 0.014). Three patients experienced increase in CD133 expression had progressive disease. Among the paired GIST patients, there was a trend of increased CD133 mRNA expression levels in patients with progressive disease, death, or tumor recurrence. CD133 mRNA levels appeared elevated among the imatinib naïve patients and imatinib appeared to reset CD133 mRNA levels among the responding GIST patients to that of healthy volunteers. Conclusion: CD133 mRNA expression levels in sarcoma patients measured by real time-PCR assay appeared to correlate with tumor response. Unpublished independent work with NASBA assay platform in other solid tumors supported our findings ( www.primagen.com ). Further work is needed to reduce assay variability, and to determine the sensitivity and specificity of assay comparing to flow cytometry and to test assay’s applicability in the antiangiogenic therapy of cancer and the angiogenic therapy of cardiovascular diseases. [Table: see text] No significant financial relationships to disclose.
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Affiliation(s)
- E. H. Lin
- M. D. Anderson Cancer Center, Houston, TX
| | - Y. Li
- M. D. Anderson Cancer Center, Houston, TX
| | - J. Trent
- M. D. Anderson Cancer Center, Houston, TX
| | | | | | | | | | - D. Li
- M. D. Anderson Cancer Center, Houston, TX
| | - L. L. Chen
- M. D. Anderson Cancer Center, Houston, TX
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Miller RM, Chen LL, Kiser GL, Giesler TL, Kaysser-Kranich TM, Palaniappan C, Federoff HJ. Temporal evolution of mouse striatal gene expression following MPTP injury. Neurobiol Aging 2005; 26:765-75. [PMID: 15708451 DOI: 10.1016/j.neurobiolaging.2004.12.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [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] [Received: 08/13/2004] [Accepted: 12/06/2004] [Indexed: 12/01/2022]
Abstract
The gradual loss of striatal dopamine and dopaminergic neurons residing in the substantia nigra (SN) causes parkinsonism characterized by slow, halting movements, rigidity, and resting tremor when neuronal loss exceeds a threshold of approximately 80%. It is estimated that there is extensive compensation for several years prior to symptom onset, during which vulnerable neurons asynchronously die. Recent evidence would argue that much of the compensatory response of the nigrostriatal system is multimodal including both pre-synaptic and striatal mechanisms. Although parkinsonism may have multiple causes, the classic syndrome, Parkinson's disease (PD), is frequently modeled in small animals by repeated administration of the selective neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Because the MPTP model of PD recapitulates many of the known behavioral and pathological features of human PD, we asked whether the striatal cells of mice treated with MPTP in a semi-chronic paradigm enact a transcriptional program that would help elucidate the response to dopamine denervation. Our findings reveal a time-dependent dysregulation in the striatum of a set of genes whose products may impact both the viability and ability to communicate of dopamine neurons in the SN.
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Affiliation(s)
- R M Miller
- Center for Aging and Developmental Biology, Aab Institute for Biomedical Research, University of Rochester School of Medicine and Dentistry, Box 645, 601 Elmwood Avenue, Rochester, NY 14642, USA
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Chen LL, Johansson JK, Hodges RR, Zoukhri D, Ghinelli E, Rios JD, Dartt DA. Differential effects of the EGF family of growth factors on protein secretion, MAPK activation, and intracellular calcium concentration in rat lacrimal gland. Exp Eye Res 2005; 80:379-89. [PMID: 15721620 DOI: 10.1016/j.exer.2004.10.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [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] [Received: 08/18/2004] [Accepted: 10/04/2004] [Indexed: 11/29/2022]
Abstract
The purpose of this study was to investigate the expression of the EGF family of growth factors and EGF receptor subtypes (ErbB1-4) present in lacrimal gland and determine the effects of these growth factors on different functions of rat lacrimal gland. RT-PCR was used to detect mRNA expression in the lacrimal gland of selected members of the EGF family of growth factors, namely EGF, transforming growth factor alpha (TGF-alpha), heparin-binding EGF (HB-EGF), and heregulin. The presence of ErbB receptors was investigated by immunofluorescence microscopy and western blot analysis. The effects of EGF, TGF-alpha, HB-EGF, and heregulin on protein secretion from lacrimal gland acini were examined using a fluorescent assay for peroxidase, a marker of protein secretion. Fura-2 tetra-acetoxymethyl ester was used to measure the effects of the growth factors on intracellular [Ca2+] ([Ca2+]i) in acini. MAPK activation in acini by these growth factors was also examined by western blot analysis using antibodies specific to phosphorylated p42/44 MAPK and total p42 MAPK. Rat lacrimal gland expressed EGF, TGF-alpha, HB-EGF, and heregulin mRNA, and all four ErbB receptors were present in the lacrimal gland as detected by western blot analyses. ErbB 1 and ErbB2 were located in basal and lateral membranes of acinar and ductal cells. The location of ErbB3 could not be determined while ErbB4 was found in ductal cells. Heregulin (10(-7) m) significantly increased protein secretion in lacrimal gland acini whereas all growth factors tested significantly increased [Ca2+]i at 10(-7) m. TGF-alpha (10(-9) m), heregulin (10(-7) m), EGF (10(-7) m), and HB-EGF (10(-7) m) significantly increased the amount of phosphorylated MAPK in lacrimal gland acini. We conclude that all members of the EGF family of growth factors studied are synthesised in rat lacrimal gland, could activate all four ErbB receptors that are present in this tissue, and differentially activate lacrimal gland functions.
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Affiliation(s)
- L L Chen
- Schepens Eye Research Institute, Harvard Medical School, Department of Ophthalmology, 20 Staniford Street, Boston, MA 02114, USA
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111
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Pepinsky RB, Lee WC, Cornebise M, Gill A, Wortham K, Chen LL, Leone DR, Giza K, Dolinski BM, Perper S, Nickerson-Nutter C, Lepage D, Chakraborty A, Whalley ET, Petter RC, Adams SP, Lobb RR, Scott DM. Design, synthesis, and analysis of a polyethelene glycol-modified (PEGylated) small molecule inhibitor of integrin {alpha}4{beta}1 with improved pharmaceutical properties. J Pharmacol Exp Ther 2005; 312:742-50. [PMID: 15485895 DOI: 10.1124/jpet.104.075648] [Citation(s) in RCA: 17] [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: 11/22/2022] Open
Abstract
Integrin alpha4beta1 plays an important role in inflammatory processes by regulating the migration of leukocytes into inflamed tissues. Previously, we identified BIO5192 [2(S)-{[1-(3,5-dichloro-benzenesulfonyl)-pyrrolidine-2(S)-carbonyl]-amino}-4-[4-methyl-2(S)-(methyl-{2-[4-(3-o-tolyl-ureido)-phenyl]-acetyl}-amino)-pentanoylamino]-butyric acid], a highly selective and potent (K(D) of 9 pM) small molecule inhibitor of alpha4beta1. Although BIO5192 is efficacious in various animal models of inflammatory disease, high doses and daily treatment of the compound are needed to achieve a therapeutic effect because of its relatively short serum half-life. To address this issue, polyethylene glycol modification (PEGylation) was used as an approach to improve systemic exposure. BIO5192 was PEGylated by a targeted approach in which derivatizable amino groups were incorporated into the molecule. Two sites were identified that could be modified, and from these, five PEGylated compounds were synthesized and characterized. One compound, 2a-PEG (K(D) of 19 pM), was selected for in vivo studies. The pharmacokinetic and pharmacodynamic properties of 2a-PEG were dramatically improved relative to the unmodified compound. The PEGylated compound was efficacious in a rat model of experimental autoimmune encephalomyelitis at a 30-fold lower molar dose than the parent compound and required only a once-a-week dosing regimen compared with a daily treatment for BIO5192. Compound 2a-PEG was highly selective for alpha4beta1. These studies demonstrate the feasibility of PEGylation of alpha4beta1-targeted small molecules with retention of activity in vitro and in vivo. 2a-PEG, and related compounds, will be valuable reagents for assessing alpha4beta1 biology and may provide a new therapeutic approach to treatment of human inflammatory diseases.
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Affiliation(s)
- R B Pepinsky
- Biogen Idec, Inc., 14 Cambridge Center, Cambridge, MA 02142, USA.
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113
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Steinert DM, Blakely LJ, Patel SR, Burgess MA, Chen LL, Trent JC, Raymond AK, Benjamin RS. Outcomes of gastrointestinal stromal tumors (GIST) and other intra-abdominal sarcomas (IAS) in the era of imatinib therapy. J Clin Oncol 2004. [DOI: 10.1200/jco.2004.22.90140.9047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
| | | | | | | | - L. L. Chen
- M. D. Anderson Cancer Center, Houston, TX
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Salganick JA, Oyedeji CO, Patel S, Burgess MA, Chen LL, Benjamin RS, Trent JC. Differential sensitivity of rhabomyosarcoma cell line clones to EGF receptor inhibition with gefitinib. J Clin Oncol 2004. [DOI: 10.1200/jco.2004.22.90140.9003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
| | | | - S. Patel
- M. D. Anderson Cancer Center, Houston, TX
| | | | - L. L. Chen
- M. D. Anderson Cancer Center, Houston, TX
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Abstract
Abstract
Reaction injection molding involves the injection of two or more kinds of liquid polymers into a mold at relative high speed. Such high inertia effect may result in air pocket inside the mold or non-uniform velocity distribution. How to design the mold entry geometry to provide uniform velocity distribution becomes one of the major topics in reaction injection molding process. Thus a new and simple method was developed in this work to optimize the reaction mold entry design. Several regulation islands were located in a fish tail entrance to help distribute the flow more even. Dimensions and locations of the islands will affect the flow uniformity and become the factors to be optimized. Taguchi's design of experiments coupled with computer flow simulation was used to achieve die geometry optimization. Effects of different dimensions of the islands on the flow uniformity can also be evaluated through statistical analyses in the flow simulation. Flow visualization technique was done by capturing flow images with high speed CCD. The experimental results showed very good agreements with the Fluent simulation results. The design methodology proposed here can help the molders in designing different reaction injection mold entries for better uniformity and performance.
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Affiliation(s)
- Y. C. Hsieh
- Department of Mechanical Engineering, National Yunlin University of Science and Technology, Yunlin, Taiwan, R. O. C
| | - L. L. Chen
- Department of Mechanical Engineering, National Yunlin University of Science and Technology, Yunlin, Taiwan, R. O. C
| | - S. C. Tseng
- Department of Mechanical Engineering, National Yunlin University of Science and Technology, Yunlin, Taiwan, R. O. C
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Leone DR, Giza K, Gill A, Dolinski BM, Yang W, Perper S, Scott DM, Lee WC, Cornebise M, Wortham K, Nickerson-Nutter C, Chen LL, LePage D, Spell JC, Whalley ET, Petter RC, Adams SP, Lobb RR, Pepinsky RB. An assessment of the mechanistic differences between two integrin alpha 4 beta 1 inhibitors, the monoclonal antibody TA-2 and the small molecule BIO5192, in rat experimental autoimmune encephalomyelitis. J Pharmacol Exp Ther 2003; 305:1150-62. [PMID: 12626659 DOI: 10.1124/jpet.102.047332] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [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: 11/22/2022] Open
Abstract
Integrin alpha 4 beta 1 plays an important role in inflammatory processes by regulating the migration of lymphocytes into inflamed tissues. Here we evaluated the biochemical, pharmacological, and pharmacodynamic properties and efficacy in experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis, of two types of alpha 4 beta 1 inhibitors, the anti-rat alpha 4 monoclonal antibody TA-2 and the small molecule inhibitor BIO5192 [2(S)-[[1-(3,5-dichloro-benzenesulfonyl)-pyrrolidine-2(S)-carbonyl]-amino]-4-[4-methyl-2(S)-(methyl-[2-[4-(3-o-tolyl-ureido)-phenyl]-acetyl]-amino)-pentanoylamino]-butyric acid]. TA-2 has been extensively studied in rats and provides a benchmark for assessing function. BIO5192 is a highly selective and potent (KD of <10 pM) inhibitor of alpha 4 beta 1. Dosing regimens were identified for both inhibitors, which provided full receptor occupancy during the duration of the study. Both inhibitors induced leukocytosis, an effect that was used as a pharmacodynamic marker of activity, and both were efficacious in the EAE model. Treatment with TA-2 caused a decrease in alpha 4 integrin expression on the cell surface, which resulted from internalization of alpha 4 integrin/TA-2 complexes. In contrast, BIO5192 did not modulate cell surface alpha 4 beta 1. Our results with BIO5192 indicate that alpha 4 beta 7 does not play a role in this model and that blockade of alpha 4 beta 1/ligand interactions without down-modulation is sufficient for efficacy in rat EAE. BIO5192 is highly selective and binds with high affinity to alpha 4 beta 1 from four of four species tested. These studies demonstrate that BIO5192, a novel, potent, and selective inhibitor of alpha 4 beta 1 integrin, will be a valuable reagent for assessing alpha 4 beta 1 biology and may provide a new therapeutic for treatment of human inflammatory diseases.
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Affiliation(s)
- D R Leone
- Biogen, Inc., 12 Cambridge Center, Cambridge, MA 02142, USA.
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117
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Abstract
This paper summarizes recent experiments conducted by the authors - experiments that studied the behavioral characteristics of large gaze shifts and the neural bases of coordinated movements of the eyes and head.
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Affiliation(s)
- D L Sparks
- Division of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
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118
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Abstract
OBJECTIVES School-based anti-tobacco education using the "social influences" model is known to reduce smoking among youth by 5-56%. Program effectiveness, however, dissipates in 1-4 years. Consequently, opinion leaders have questioned whether a more intensive national educational effort would be economically efficient. To address this question, we evaluated the cost-effectiveness of enhanced nationwide school-based anti-tobacco education relative to the status quo. METHODS To estimate cost-effectiveness, we created the Tobacco Policy Model, a system dynamics computer simulation model. The model relies on secondary data and is designed to calculate the expected costs and public health gains of any tobacco policy or intervention over any time frame. RESULTS Over 50 years, cost-effectiveness is estimated to lie between $4,900 and $340,000 per quality-adjusted life-year (QALY), depending on the degree and longevity of program effectiveness. Assuming a 30% effectiveness that dissipates in 4 years, cost-effectiveness is $20,000/QALY. Sensitivity analysis reveals that cost-effectiveness varies with cost, survival, and quality-of-life estimates but cost-effectiveness ratios generally remain favorable. CONCLUSIONS Although not cost saving, a much more intensive school-based anti-tobacco educational effort would be an economically efficient investment for the nation.
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Affiliation(s)
- T O Tengs
- Health Priorities Research Group, University of California, Irvine, California 92697-7075, USA.
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119
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Abstract
Although sublingual captopril has been used clinically to treat hypertensive emergencies, a mechanistic understanding of sublingual permeation will facilitate the optimization of drug delivery. A correlation of sublingual steady-state flux with donor captopril concentration in a porcine model showed the absence of saturability and suggested a passive diffusion permeation mechanism. A simultaneous evaluation of permeability and partition coefficient demonstrated that the paracellular route is the predominant pathway for sublingual permeation. The enhancement factors of specific ion permeabilities in the presence of tight junction perturbants indicated that although the paracellular pathway is preferred by the ionized species of captopril, the lipophilic transcellular pathway is preferred by the neutral, un-ionized species.
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Affiliation(s)
- D J Chetty
- College of Pharmacy, Rutgers University, P.O. Box 789, Piscataway, New Jersey 08855-0789, USA.
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120
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Abstract
AIM: To determine the frequencies of HGV and TTV infections in blood donors in Hangzhou.
METHODS: RT-nested PCR for HGV RNA detection and semi-nested PCR for TTV DNA detection in the sera from 203 blood donors, and nucleotide sequence analysis were performed.
RESULTS: Thirty-two (15.8%) and 30 (14.8%) of the 203 serum samples were positive for HGV RNA and TTV DNA, respectively. And 5 (2.5%) of the 203 serum samples were detectable for both HGV RNA and TTV DNA. Homology of the nucleotide sequences of HGV RT-nested PCR products and TTV semi-nested PCR products from 3 serum samples compared with the reported HGV and TTV sequences was 89.36%, 87.94%, 88.65% and 63.51%, 65.77% and 67.12%, respectively.
CONCLUSION: The infection rates of HGV and/or TTV in blood donors are relatively high, and to establish HGV and TTV examinations to screen blood donors is needed for transfusion security. The genomic heterogeneity of TTV or HGV is present in the isolates from different areas.
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Affiliation(s)
- J Yan
- Department of Pathogenic Biology, Medical School of Zhejiang University, 353 Yan An Road, Hangzhou 310006, Zhejiang Province,China.
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121
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Peng SE, Lo CF, Lin SC, Chen LL, Chang YS, Liu KF, Su MS, Ko GH. Performance of WSSV-infected and WSSV-negative Penaeus monodon postlarvae in culture ponds. Dis Aquat Organ 2001; 46:165-172. [PMID: 11710550 DOI: 10.3354/dao046165] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In a survey of 27 Penaeus monodon culture ponds stocked with postlarvae (approximately PL10) at medium density (approximately 40 shrimp m(-2)), single-step nested white spot syndrome virus (WSSV) PCR was used to measure the WSSV infection rates in the shrimp populations within 1 mo after stocking. Seven ponds were initially WSSV-free, and the shrimp in 5 of these were harvested successfully. In the ponds (n = 6) where detection rates were higher than 50%, mass mortality occurred during the growth period, and none of these ponds was harvested successfully. In a subsequent study, P. monodon brooders were classified into 3 groups according to their WSSV infection status before and after spawning: brooders that were WSSV-positive before spawning were assigned to group A; spawners that became WSSV-positive only after spawning were assigned to group B; and group C consisted of brooders that were still WSSV-negative after spawning. WSSV screening showed that 75, 44 and 14%, respectively, of group A, B and C brooders produced nauplii that were WSSV-positive. Most (57%; 16/28) of the brooders in group A produced nauplii in which the WSSV prevalence was high (>50%). When a pond was stocked with high-prevalence nauplii from 1 of these group A brooders, an outbreak of white spot syndrome occurred within 3 wk and only approximately 20% of the initial population survived through to harvest (after 174 d). By contrast, 2 other ponds stocked with low-prevalence and WSSV-negative nauplii (derived respectively from 2 brooders in group B), both had much higher survival rates (70 to 80%) and yielded much larger (approximately 3x by weight) total harvests. We conclude that testing the nauplii is an effective and practical screening strategy for commercially cultured P. monodon.
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Affiliation(s)
- S E Peng
- Department of Zoology, National Taiwan University, Taipei, ROC
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122
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Lin S, Huang HC, Chen LL, Lee CC, Huang TS. GL331 induces down-regulation of cyclin D1 expression via enhanced proteolysis and repressed transcription. Mol Pharmacol 2001; 60:768-75. [PMID: 11562439] [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: 02/21/2023] Open
Abstract
GL331 is a novel podophyllotoxin-derived compound. In this study, GL331 induced human lung adenocarcinoma cell line CL1-5 growth arrest before death during the initial 24-h incubation period. We found that GL331 had no inhibitory effect on the expression of cyclins E, A, B1, CDK 4, and CDK 2; instead, its cell growth-inhibitory effect was partly attributable to an early down-regulation of cyclin D1 expression and in turn the reduction of retinoblastoma protein phosphorylation. GL331 enhanced the proteolysis of cyclin D1, and a proteasome inhibitor was able to block GL331-caused cyclin D1 reduction, suggesting that GL331-stimulated cyclin D1 degradation was through proteasomal processes. Additionally, GL331 reduced cellular cyclin D1 mRNA level down to 45% of control in 4 h and further to around 20% in 12 h. However, GL331 did not accelerate the disappearance of cyclin D1 mRNA under the condition of transcription blockage induced by actinomycin D. It was reported that a certain region in the 3'-untranslated region (UTR) of cyclin D1 mRNA mediated the mRNA degradation upon extracellular stresses. Herein, transient transfection studies demonstrated that the 3'-UTR insertion did not confer the susceptibility of luciferase reporter gene to the GL331 treatment. Together, these data suggested that GL331 did not decrease the stability of cyclin D1 mRNA. On the other hand, we found that GL331 specifically inhibited the cyclin D1 promoter-driven luciferase reporter activity. Western blot analyses showed that GL331 decreased the level of phosphorylated extracellular signal-regulated kinase (Erk), with no effect on p38 or c-Jun NH(2)-terminal kinase. Furthermore, GL331's inhibition of cyclin D1 promoter was attenuated by ectopic Erk-2 overexpression. These data suggested that GL331 inhibited cyclin D1 gene transcription via the Erk signaling pathway. In summary, we report that GL331 induced an early decline of cyclin D1 expression by dual mechanisms: 1) enhancement of protein turnover and 2) repression of Erk-mediated gene transcription.
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Affiliation(s)
- S Lin
- Cooperative Laboratory at Veterans General Hospital, Cancer Research Division, National Health Research Institutes, Taipei, Taiwan, Republic of China
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123
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Chen LL, Whitty A, Scott D, Lee WC, Cornebise M, Adams SP, Petter RC, Lobb RR, Pepinsky RB. Evidence that ligand and metal ion binding to integrin alpha 4beta 1 are regulated through a coupled equilibrium. J Biol Chem 2001; 276:36520-9. [PMID: 11473127 DOI: 10.1074/jbc.m106216200] [Citation(s) in RCA: 20] [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: 12/26/2022] Open
Abstract
We have used the highly selective alpha(4)beta(1) inhibitor 2S-[(1-benzenesulfonyl-pyrrolidine-2S-carbonyl)-amino]-4-[4-methyl-2S-(methyl-[2-[4-(3-o-tolyl-ureido)-phenyl]-acetyl]-amino)-pentanoylamino]-butyric acid (BIO7662) as a model ligand to study alpha(4)beta(1) integrin-ligand interactions on Jurkat cells. Binding of [(35)S]BIO7662 to Jurkat cells was dependent on the presence of divalent cations and could be blocked by treatment with an excess of unlabeled inhibitor or with EDTA. K(D) values for the binding of BIO7662 to Mn(2+)-activated alpha(4)beta(1) and to the nonactivated state of the integrin that exists in 1 mm Mg(2+), 1 mm Ca(2+) were <10 pm, indicating that it has a high affinity for both activated and nonactivated integrin. No binding was observed on alpha(4)beta(1) negative cells. Through an analysis of the metal ion dependences of ligand binding, several unexpected findings about alpha(4)beta(1) function were made. First, we observed that Ca(2+) binding to alpha(4)beta(1) was stimulated by the addition of BIO7662. From solution binding studies on purified alpha(4)beta(1), two types of Ca(2+)-binding sites were identified, one dependent upon and the other independent of BIO7662 binding. Second, we observed that the metal ion dependence of ligand binding was affected by the affinity of the ligand for alpha(4)beta(1). ED(50) values for the metal ion dependence of the binding of BIO7762 and the binding of a lower affinity ligand, BIO1211, differed by 2-fold for Mn(2+), 30-fold for Mg(2+), and >1000-fold for Ca(2+). Low Ca(2+) (ED(50) = 5-10 microm) stimulated the binding of BIO7662 to alpha(4)beta(1). The effects of microm Ca(2+) closely resembled the effects of Mn(2+) on alpha(4)beta(1) function. Third, we observed that the rate of BIO7662 binding was dependent on the metal ion concentration and that the ED(50) for the metal ion dependence of BIO7662 binding was affected by the concentration of the BIO7662. These studies point to an even more complex interplay between metal ion and ligand binding than previously appreciated and provide evidence for a three-component coupled equilibrium model for metal ion-dependent binding of ligands to alpha(4)beta(1).
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Affiliation(s)
- L L Chen
- Biogen, Inc., Cambridge, Massachusetts 02142, USA
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124
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Chen LL, Yan J. Porphyromonas gingivalis lipopolysaccharide activated bone resorption of osteoclasts by inducing IL-1, TNF, and PGE. Acta Pharmacol Sin 2001; 22:614-8. [PMID: 11749825] [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: 02/23/2023] Open
Abstract
AIM To study the effects of Porphyromonas gingivalis lipopolysaccharide (Pg-LPS) on inducing interleukin-1 (IL-1), tumor necrosis factor (TNF), prostaglandin E (PGE), and activating osteoclasts, in order to understand mechanism of osteoclast activation. METHODS Pg-LPS was prepared by phenol-water method. IL-1, TNF, and PGE induced by Pg-LPS were isolated by chromatography. Ca2+ concentration was detected by atomic absorption spectrophotometry. Acid phosphatase and carbonic anhydrase in periodontal membranes were examined by histochemistry. RESULTS Pg-LPS was able to stimulate peripheral blood mononuclear cells (PBMC) or the cells from human periodontal tissue secreting IL-1, TNF, and PGE. The outputs of these cytokines were increased in pace with the enhancement of Pg-LPS at the dose range of 0.5 - 5.0 mg/L. All of the three cytokines showed activities of accelerating Ca2+ release from rat calvarial bones, and the activity of PGE was the strongest. The amounts of both the acid phosphatase and carbonic anhydrase in the periodontal membranes of Pg-LPS injected rats were obviously increased (P < 0.01). In the periodontal membranes of Pg-LPS injected rats, the amount of activated osteoclasts were obviously increased in pace with Pg-LPS injection times (P < 0.01). However, the activating rates of osteoclasts were stable to approximately 65 % because of the increase of inactivated osteoclasts. CONCLUSION Pg-LPS possessed strong activities to induce human PBMC and the cells from human periodontal tissue to produce IL-1, TNF, and PGE in a dose-dependent m anner within a certain concentration range of the LPS. Pg-LPS could efficiently activate osteoclasts, and the mechanism of osteoclast activation was probably associated with the increase of acid phosphatase and carbonic anhydrase.
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Affiliation(s)
- L L Chen
- Department of Stomatology, the Second Affiliated Hospital, Medical School of Zhejiang University, Hangzhou 310009, China
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125
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Abstract
An amylopullulanase gene (apuTS) from Bacillus stearothermophilus TS-23 was cloned and characterized. apuTS consisted of an open reading frame of 6054 bp encoding a protein of 2018 amino acids with a calculated M(r) of 223811. The deduced amino acid sequence revealed four highly conserved regions that are common among amylolytic enzymes. In the C-terminal region, a six-amino-acid sequence (Pro-Gly-Ser-Gly-Thr-Thr) is repeated nine times. It shared the highest degree of homology with the amylopullulanase of Bacillus sp. XAL601. The enzyme also had moderate homology with amylopullulanases from thermophilic anaerobic bacteria. Low levels of homology were observed between the ApuTS of B. stearothermophilus TS-23 and amylopullulanases of Pyrococcus abyssi Orsay, P. furiosus and Bacillus sp. KSM1378. When the intact coding region of apuTS was expressed in Escherichia coli under the control of the lac promoter, the product was degenerate, as revealed by amylase activity staining after SDS/PAGE. The largest active polypeptide had an M(r) of about 220000, while the smallest one had an M(r) of about 105000. Upstream of the apuTS gene, a gene orfX was fortuitously cloned. The putative OrfX protein was weakly related to the myosin heavy chain. It was predicted to contain a central, 179-residue-long, coiled-coil domain.
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Affiliation(s)
- J T Chen
- Food Industry Research and Development Institute, P.O. Box 246, Hsinchu 30099, Taiwan, Republic of China
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126
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Abstract
A method for constructing a simple, durable injection-microelectrode (injectrode) is described. The injectrode can record neuronal activity, stimulate neuronal tissues, or inject substances locally through its tip. The injectrode is lightweight and is easy to construct from commercially available parts, and it can be used repeatedly for multiple recordings and injections. Since dura penetration can damage fragile electrode tips, a reliable method to pass the injectrode through an intact dura matter is described.
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Affiliation(s)
- L L Chen
- Division of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA.
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127
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Feigelson SW, Grabovsky V, Winter E, Chen LL, Pepinsky RB, Yednock T, Yablonski D, Lobb R, Alon R. The Src kinase p56(lck) up-regulates VLA-4 integrin affinity. Implications for rapid spontaneous and chemokine-triggered T cell adhesion to VCAM-1 and fibronectin. J Biol Chem 2001; 276:13891-901. [PMID: 11102438 DOI: 10.1074/jbc.m004939200] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [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: 11/06/2022] Open
Abstract
In circulating lymphocytes, the VLA-4 integrin preexists in multiple affinity states that mediate spontaneous tethering, rolling, and arrest on its endothelial ligand, vascular cell adhesion molecule-1 (VCAM-1). The regulation and function of VLA-4 affinity in lymphocytes has never been elucidated. We show here that p56(lck), the major Src kinase in T cells, is a key regulator of high affinity VLA-4. This high affinity is essential for the rapid development of firm adhesion of resting T cells to VCAM-1 and to their extracellular matrix ligand, fibronectin. Lck-regulated VLA-4 function does not require intact TCR nor several key components of the TCR signaling pathway, including ZAP-70 and SLP-76. Furthermore, stimulation of p56(lck) by the phosphatase inhibitor, pervanadate, triggers firm VLA-4-dependent adhesion to VCAM-1. Although Lck is not required for chemokine receptor signaling to mitogen-activated protein kinase, the presence of Lck-regulated high affinity VLA-4 also facilitates firm adhesion triggered by the chemokine, SDF-1, at short-lived contacts. Surprisingly, bond formation rates, ability to tether cells to VLA-4 ligand, and VLA-4 tether bond stability under shear flow are not affected by VLA-4 affinity or Lck activity. Thus, the ability of high affinity VLA-4 to arrest cells on VCAM-1 under flow arises from instantaneous post-ligand strengthening rather than from increased kinetic stability of individual VLA-4 bonds. These results suggest that p56(lck) maintains high affinity VLA-4 on circulating lymphocytes, which determines their ability to strengthen VLA-4 adhesion and rapidly respond to proadhesive chemokine signals at endothelial sites.
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Affiliation(s)
- S W Feigelson
- Department of Immunology, The Weizmann Institute of Science, Rehovot 76100, Israel
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128
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Nomiyama T, Nakashima H, Chen LL, Tanaka S, Miyauchi H, Yamauchi T, Sakurai H, Omae K. N , N -Dimethylformamide: significance of dermal absorption and adjustment method for urinary N -methylformamide concentration as a biological exposure item. Int Arch Occup Environ Health 2001; 74:224-8. [PMID: 11355298 DOI: 10.1007/s004200000207] [Citation(s) in RCA: 44] [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: 11/25/2022]
Abstract
OBJECTIVES To clarify the potential for dermal absorption of N,N-dimethylformamide (DMF) (CAS No. 68-12-2) vapor, and the appropriate adjustment method and the half-lives of urinary concentrations of N-methylformamide (NMF) as the biological exposure item of DMF. METHODS Thirteen healthy male volunteers (mean age: 22.7 years, range: 20-27) were exposed to DMF vapor twice, via both the skin and the lung, for 4 h at concentrations below 10 ppm, the recommended occupational exposure limit set by the Japan Society for Occupational Health, the American Conference of Governmental and Industrial Hygienists, and Deutsche Forschungsgemeinschaft, under conditions of 27 degrees C and 44% humidity. Each volunteer was exposed to DMF via the skin in a whole-body type exposure chamber and outside the chamber, via the lung by a respirator connected to the chamber. Exposure levels were 6.2 +/- 1.0 ppm in dermal exposure and 7.1 +/- 1.0 ppm in inhalation exposure. Urine samples were collected at every opportunity until 72 h after exposure; and NMF, as well as volume, creatinine, and specific gravity were measured. Dermal and inhalation intakes were compared after adjusting concentrations. RESULTS AND CONCLUSIONS DMF vapor absorptions via the skin and the lung were estimated to be 40.4 and 59.6%, respectively. Workers need to be aware of the risk of dermal absorption of DMF vapor as well as of the liquid. Though NMF concentrations adjusted by creatinine, specific gravity, and urinary volume showed good correlation with total NMF excretion and the absolute amount of NMF at each sampling time, creatinine-adjusted NMF concentration correlated better than the others. The biological half-life of urinary NMF after dermal exposure, 4.75 +/- 1.63 h, was longer than that after respiratory exposure, 2.42 +/- 0.63 h.
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Affiliation(s)
- T Nomiyama
- Department of Preventive Medicine and Public Health, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.
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129
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Abstract
We used scanning electron microscopy to count the number of mucous gland openings in the tracheae and lower portion of the larynges of the rat, guinea pig, hamster, mouse and rabbit. Cells of the airway surface epithelium were removed by protease digestion better to visualise the gland openings. The distribution of glands was further studied by conventional histology and by PAS/Alcian blue staining of whole mounts. In all rodent species, gland openings in the larynx occurred with a frequency of 1-2 per mm2. Mice had no gland openings in their tracheae, and hamsters, only a handful. Rat tracheae contained 126+/-42 gland openings (+/-S.D.; n = 6) at a frequency of approximately 0.6 per mm2 at the top of the trachea and approximately 0.15 per mm2 at the bottom. Guinea pig tracheae contained 153+/-90 gland openings (+/-S.D.; n = 5), with 54% being in the top 40% of the trachea. In both rat and guinea pig, tracheal glands were found in the ventral aspect between the cartilaginous rings, and were absent from the dorsal membranous portion. Gland openings in most species were simple circles of approximately 50 microm diameter. However, glands in the rat trachea generally opened obliquely into shallow (approximately 20 microm deep) oval troughs (approximately 150 x 75 microm), which had their long axes oriented from head to tail. In the rabbit, there was no evidence of tracheal or laryngeal glands histologically. However, the tracheal and laryngeal surfaces contained numerous pits (approximately 30 microm diameter) distributed evenly over and between cartilages at a frequency of approximately 4 per mm2. These may correspond to the 'nests' of goblet cells described by others.
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Affiliation(s)
- J H Widdicombe
- Children's Hospital Oakland Research Institute, CA, USA.
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130
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Nomiyama T, Nakashima H, Sano Y, Chen LL, Tanaka S, Miyauchi H, Yamauchi T, Sakurai H, Omae K. Does the polymorphism of cytochrome P-450 2E1 affect the metabolism of N,N-dimethylformamide? Comparison of the half-lives of urinary N-methylformamide. Arch Toxicol 2001; 74:755-9. [PMID: 11305777 DOI: 10.1007/s002040000197] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [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: 10/27/2022]
Abstract
The aim of this study was to clarify whether phenotypic variation exists when subjects with different genotypes of cytochrome P450 2E1 (CYP2E1) are exposed to N,N-dimethylformamide (DMF). The genotypes of CYP2E1 were confirmed in 123 healthy male volunteer subjects. Of the 123 subjects, the numbers of c1 homozygotes, c2 heterozygotes, and c2 homozygotes were 77, 45, and 1, respectively. Seven of the c1 homozygotes, five of the c2 heterozygotes, and the one c2 homozygote (mean age: 22.7 years, range: 20-27 years) were exposed to DMF vapor twice, once via the skin and once via the lung, for a total of 8 h per subject at a concentration below 10 ppm, the occupational exposure limit recommended by the Japan Society for Occupational Health, the American Conference of Governmental and Industrial Hygienists, and Deutsche Forschungsgemeinschaft, at 27 degrees C and 44% relative humidity. Exposure levels were 6.2+/-1.0 ppm in dermal exposure and 7.1+/-1.0 ppm in inhalation exposure. Urine samples were collected until 72 h after exposure. The half-lives of urinary N-methylformamide (NMF) were obtained as the phenotype. The average urinary NMF half-lives of the c1 homozygotes, the c2 heterozygotes, and the c2 homozygote were 3.86+/-1.90, 4.38+/-1.53, and 4.2 h after dermal exposure, and 1.58+/-0.42, 1.84+/-0.61, and 3.2 h after respiratory exposure. The NMF half-lives of the c1 homozygotes were not significantly different from those of the c2 heterozygotes, and there were no differences between the NMF half-lives on the subjects with and without the c2 allele. Even though the data were obtained from only one c2 homozygote, it is noteworthy that the NMF half-life of this subject was slightly less than that of the c1 homozygotes after respiratory exposure.
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Affiliation(s)
- T Nomiyama
- Department of Preventive Medicine and Public Health, School of Medicine, Keio University, Tokyo, Japan.
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131
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Hwang TL, Lue MC, Chen LL. Early use of cyclic TPN prevents further deterioration of liver functions for the TPN patients with impaired liver function. Hepatogastroenterology 2000; 47:1347-50. [PMID: 11100349] [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: 02/18/2023]
Abstract
BACKGROUND/AIMS Impaired liver function is frequently found in patients who need prolonged total parenteral nutrition. Cyclic total parenteral nutrition can minimize the adverse effects of long-term total parenteral nutrition, such as hepatic complication. The adequate timing to shift to use cyclic total parenteral nutrition for patients with impaired liver function may prevent further hepatic dysfunction. METHODOLOGY A prospective study of 65 patients who need total parenteral nutrition and have impaired liver functions was performed. Cyclic total parenteral nutrition was used in different groups of patients, when their total bilirubin levels were just over 5 mg%, 10 mg%, or 20 mg% during the course of total parenteral nutrition. The patients of control groups received straight non-cyclic total parenteral nutrition. All the patients had stable vital signs without major stress, such as sepsis or acute bleeding. Ten patients (A2) in Group A were shifted to cyclic total parenteral nutrition when their total bilirubin was just over 5 mg%; the other 10 patients (A1) continued the non-cyclic total parenteral nutrition. Eleven patients (B2) in Group B were shifted to cyclic total parenteral nutrition when their total bilirubin was just over 10 mg%; the other 11 patients (B1) continued the non-cyclic total parenteral nutrition. Ten patients (C2) in Group C were shifted to cyclic total parenteral nutrition when their total bilirubin was just over 20 mg%; the other 13 patients (C1) continued the non-cyclic total parenteral nutrition. The average energy intake among 3 groups had no difference. Their liver functions were examined each week for 2 weeks. RESULTS The results showed that the patients with non-cyclic total parenteral nutrition had significant increase of direct-total bilirubin and alkaline phosphatase (P < 0.05) in Group A and significant decrease of albumin accompanied with increase of GOT, GPT, direct/total bilirubin (P < 0.05) in Group B. The patients either using cyclic or non-cyclic total parenteral nutrition showed significant decrease of albumin and increase of direct/total bilirubin (P < 0.05) in Group C. CONCLUSIONS We conclude that the early use of cyclic total parenteral nutrition may prevent deterioration of liver function for the patients with jaundice and need prolonged total parenteral nutrition.
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Affiliation(s)
- T L Hwang
- Department of Nutritional Therapy, Chang Gung Memorial Hospital, School of Medicine, Chang Gung University, Taipei, Taiwan
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Affiliation(s)
- J Mao
- MGH Pain Center, Massachusetts General Hospital, Harvard Medical School, Boston 02114, USA.
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133
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Abstract
Simultaneous single neuron and local field potential (LFP) recordings were made in arm-related areas of the cerebellar nuclei (CN) and primary motor cortex (M1) of two monkeys during a reaching and button pressing task. Microstimulation of focal sites in CN caused short latency (median = 3.0 ms) increases in discharge in 25% of 210 M1 neurons. Suppressive effects were less common (13%) and observed at longer latencies (median = 9.9 ms). Stimulation in CN also caused reciprocal facilitation and suppression in averages of antagonist muscle electromyograms (EMGs). The latency of these effects was approximately 8-11 ms. In contrast to the selectivity of unit and EMG effects, stimulation-evoked changes in LFP occurred over a broad range of sites. There were no significant short-latency effects detected in cross-correlation histograms between single neurons in CN and M1. However, CN spike-triggered averages of M1 LFPs were observed in a few cases (10% of 126 cases). In one-half of these, there were effects both before and after the CN spikes, which may reflect causal effects from M1 to CN, as well as from CN to M1. Overall, these results demonstrate a spatially specific, short latency, primarily excitatory pathway from CN to M1. The relatively rare effects at the single neuron level may have resulted from the difficulty in achieving optimal alignment between cerebellar and cerebral sites because of the specificity of these connections.
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Affiliation(s)
- R N Holdefer
- Department of Physiology and the Northwestern University Institute for Neuroscience, Northwestern University Medical School, Chicago, Illinois 60611, USA
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134
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Chen LL. [The management of 126 cases of posterior cracked crown of tooth and its effective observation]. Shanghai Kou Qiang Yi Xue 2000; 9:86-7. [PMID: 15014816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
OBJECTIVE To detect the treatment and effect of posterior cracked tooth. METHODS 162 posterior cracked teeth of 158 cases, including enamel fissure and dentin fissure, all there cases undergone the synthetical treatment and follow up in different period, the longest observation period was 2.5 years. RESULTS The healing and improved rate of 162 cracked teeth 90.74%. Among cases of failure, we have founded 6 cases of acute pulpitis (3.7%), 3 cases of alveodental abscess (1.85%), 2 cases of chronic apical periodontitis (1.24%), 4 cases of tooth fracture (2.4%). CONCLUSION Cracked tooth was caused by multiple factors. Early diagnosis, synthetical treatment, and follow up in different period are 3 main factors in treatment.
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Affiliation(s)
- L L Chen
- Department Stomatology, Huasan hospital affiliated to Shanghai Medical University. Shanghai 200040, China
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Huang TS, Shu CH, Chao Y, Chen SN, Chen LL. Activation of MAD 2 checkprotein and persistence of cyclin B1/CDC 2 activity associate with paclitaxel-induced apoptosis in human nasopharyngeal carcinoma cells. Apoptosis 2000; 5:235-41. [PMID: 11225845 DOI: 10.1023/a:1009652412399] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [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: 11/12/2022]
Abstract
Paclitaxel (Taxol) is a microtubule-interfering agent that induced persistent and transient G2/M arrest before apoptosis in human nasopharyngeal carcinoma (NPC) cells at high and low concentrations, respectively. In this study, we intended to explore the underlying molecular events and found that cellular cyclin B1/CDC 2 kinase activity was increased and persisted for >6 h upon paclitaxel treatment both at high and low concentrations. Furthermore, activation of MAD 2 checkprotein could account for the loss of cyclin B1 ubiquitination and the persistence of cyclin B1/CDC 2 activation in the cases. To investigate the involvement of cyclin B1 and MAD 2 activation in paclitaxel-induced apoptosis, we introduced affinity-purified anti-cyclin B1 and MAD 2 antibodies into NPC cells by electroporation before the further paclitaxel treatment. The antibodies against cyclin B1 and MAD 2 indeed attenuated paclitaxel-induced cytotoxicity and DNA fragmentation. Our study suggests that activation of cyclin B1/CDC 2 and MAD 2 were the M-phase events required for paclitaxel-induced apoptosis in NPC cells. The dys-regulated cyclin B1/CDC 2 activation could enhance the prometaphase progression, but activation of MAD 2 rendered cells inable to exit from the metaphase. Under this circumstance, cells were probably going to "mitotic catastrophe" and ultimately, destined to apoptosis.
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Affiliation(s)
- T S Huang
- Cancer Research Division, National Health Research Institutes, Taipei, Taiwan, Republic of China.
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Solomon C, Christian DL, Chen LL, Welch BS, Kleinman MT, Dunham E, Erle DJ, Balmes JR. Effect of serial-day exposure to nitrogen dioxide on airway and blood leukocytes and lymphocyte subsets. Eur Respir J 2000; 15:922-8. [PMID: 10853860 DOI: 10.1034/j.1399-3003.2000.15e19.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [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: 11/23/2022]
Abstract
Nitrogen dioxide (NO2) is a free radical-producing oxidant gas. Inhalation of NO2 could cause airway inflammation, and decrease immune function. This experiment tested the hypothesis that exposure to NO2 would: 1) increase leukocytes in bronchoalveolar lavage (BAL); and 2) change the distribution of lymphocyte subsets and activation in BAL and peripheral blood (PB). Using a counter-balanced, repeated-measures design, 15 healthy volunteers were exposed to filtered air (FA) or 2.0 parts per million NO2 for 4 h x day(-1) (4 x 30 min of exercise), for three consecutive days. Bronchoscopy was performed 18 h following each exposure set, and PB was drawn pre-exposure and pre-bronchoscopy. Flow cytometry was used to enumerate lymphocyte subsets and activation makers in BAL and PB. In the bronchial fraction, there was an increase in the percentage of neutrophils following NO2 exposure compared to FA (median (interquartile range): 10.6 (4.8-17.2)% versus 5.3 (2.5-8.3)%; p=0.005). In the BAL, there was a decrease in the percentage of T-helper cells following NO2 exposure compared to FA (55.9 (40.8-62.7)% versus 61.6 (52.6-65.2)%; p=0.022). For PB, there were no between-condition differences in any leukocyte or lymphocyte subsets, or activation. In conclusion exposure to nitrogen dioxide results in bronchial inflammation and a minimal change in bronchoalveolar lavage T-helper cells, and no changes in peripheral blood cells.
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Affiliation(s)
- C Solomon
- Lung Biology Center, University of California, San Francisco 94143, USA
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137
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Herring JH, Chen CJ, Chen LL. Confirmation of persistent closure of surgically repaired macular hole in subsequent retinal detachment by optical coherence tomography. Ophthalmic Surg Lasers 2000; 31:243-4. [PMID: 10847505] [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: 02/16/2023]
Abstract
Idiopathic macular holes have shown response to surgical intervention with vitrectomy, presumably because of glial cell proliferation in the reapproximated tissue. We describe a patient with postoperative closure of a macular hole who subsequently developed a retinal detachment involving the macular area. Despite the detachment, the macular hole remained closed as evidenced by biomicroscopy and optical coherence tomography (OCT). OCT provides accurate documentation and assessment of pre- and postoperative conditions in macular hole surgery.
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Affiliation(s)
- J H Herring
- Department of Ophthalmology, University of Mississippi Medical Center, Jackson 39216-4505, USA
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138
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Chen LL, Lo CF, Chiu YL, Chang CF, Kou GH. Natural and experimental infection of white spot syndrome virus (WSSV) in benthic larvae of mud crab Scylla serrata. Dis Aquat Organ 2000; 40:157-161. [PMID: 10782350 DOI: 10.3354/dao040157] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
White spot syndrome virus (WSSV), the causative agent of white spot syndrome in shrimp, has a wide host range which extends to crabs, copepods and other arthropods. In this study, benthic larvae of the mud crab Scylla serrata were captured from Taiwan's coastal waters and screened for the presence of WSSV by polymerase chain reaction (PCR) and in situ hybridization. WSSV was detected in around 60% of the larvae, and this prevalence rate remained fairly constant when the captured larvae were subsequently maintained in an aerated system in the laboratory. WSSV-free larvae obtained from a hatchery were challenged by immersion in a WSSV inoculum. Fifteen days after challenge, cumulative mortality in the experimental group reached 43% compared to 20% in the control group. PCR detection of WSSV in both moribund and surviving specimens clearly implicated the virus as the cause of death in most cases. Histological and in situ hybridization data confirmed that WSSV tissue tropism in Scylla serrata crab larvae is similar to that found in shrimp.
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Affiliation(s)
- L L Chen
- Department of Zoology, National Taiwan University, Taipei, ROC
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139
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Hsu HC, Lo CF, Lin SC, Liu KF, Peng SE, Chang YS, Chen LL, Liu WJ, Kou GH. Studies on effective PCR screening strategies for white spot syndrome virus (WSSV) detection in Penaeus monodon brooders. Dis Aquat Organ 1999; 39:13-19. [PMID: 11407400 DOI: 10.3354/dao039013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We re-tested stored (frozen) DNA samples in 5 independent polymerase chain reaction (PCR) replicates and confirmed that equivocal test results from a previous study on white spot syndrome virus (WSSV) in brooders and their offspring arose because amounts of WSSV DNA in the test samples were near the sensitivity limits of the detection method. Since spawning stress may trigger WSSV replication, we also captured a fresh batch of 45 brooders for WSSV PCR testing before and after spawning. Replicates of their spawned egg batches were also WSSV PCR tested. For these 45 brooders, WSSV prevalence before spawning was 67% (15/45 1-step PCR positive, 15/45 2-step PCR positive and 15/45 2-step PCR negative). Only 27 (60%) spawned successfully. Of the successful spawners, 56% were WSSV PCR positive before spawning and 74% after. Brooders (15) that were heavily infected (i.e. 1-step PCR positive) when captured mostly died within 1 to 4 d, but 3 (20%) did manage to spawn. All their egg batch sub-samples were 1-step PCR positive and many failed to hatch. The remaining 30 shrimp were divided into a lightly infected group (21) and a 2-step PCR negative group (9) based on replicate PCR tests. The spawning rates for these 2 groups were high (81 and 78%, respectively). None of the negative spawners (7) became WSSV positive after spawning and none gave egg samples positive for WSSV. In the lightly infected group (21), 6 brooders were 2-step WSSV PCR negative and 15 were 2-step WSSV PCR positive upon capture. However, all of them were WSSV PCR positive in replicate tests and after spawning or death. Four died without spawning. The remaining 17 spawned but only 2 gave egg samples PCR negative for WSSV. The other 15 gave PCR positive egg samples, but they could be divided into 2 spawner groups: those (7) that became heavily infected (i.e. 1-step PCR positive) after spawning and those (8) that remained lightly infected (i.e. became or remained 2-step PCR positive only). Of the brooders that became heavily infected after spawning, almost all egg sample replicates (91 %) tested 2-step PCR positive. One brooder even gave heavily infected (i.e. 1-step PCR positive) egg samples. For the brooders that remained lightly infected after spawning, only 27% of the egg sample replicates were 2-step PCR positive. Based on these results, we recommend that to avoid false negatives in WSSV PCR brooder tests screening tests should be delayed until after spawning. We also recommend, with our PCR detection system, discarding all egg batches from brooders that are 1-step PCR positive after spawning. On the other hand, it may be possible with appropriate monitoring to use eggs from 2-step PCR positive brooders for production of WSSV-free or lightly infected postlarvae. These may be used to stock shrimp ponds under low-stress rearing conditions.
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Affiliation(s)
- H C Hsu
- Department of Zoology, National Taiwan University, Taipei, ROC
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140
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Chen LL, Peng SS, Cao HJ. [The use of expert computer system in the diagnosis of oral diseases]. Shanghai Kou Qiang Yi Xue 1999; 8:245-7. [PMID: 15048228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Affiliation(s)
- L L Chen
- Department of Orthodontics,School of Medicine College,ShanghaiShanghai Second University. Shanghai 200021 China
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141
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Abstract
The hypotheses of this study are that the permeation of ionizable molecules follows the pH-partition theory, that the preferred transport pathway for penetrants depends on their charge status and that transport resistance is related to the membrane-coating granules (MCG). Transcellular resistance is believed to be proportional to the volume of MCG in the intracellular space while paracellular resistance is believed to result from the extrusion of the lipid contents of the MCG into the intercellular space. Nicotine, an ionizable model compound with two pK(a) values (3.4 and 8.2), was chosen as a molecular probe to investigate the pH-partition theory on permeation through porcine oramucosae, to characterize the differences in permeability among various oramucosae, and to explore the preferred transport pathways of each nicotine species through oramucosae. The pH-partition theory was proved from the observations that permeability, partition coefficient and diffusivity of nicotine varied as a function of pH. The keratinized gingiva was found to have greater permeability than the non-keratinized buccal and sublingual mucosae. The neutral nicotine species had a higher permeability than the ionized species due to its higher partition coefficient and diffusivity. A mechanistic analysis (permeability ratio-pH profile) was conducted to determine the preferred transport pathway of each nicotine species. The permeability of neutral nicotine was found to be proportional to the occupied volume of MCG in the intracellular space. This indicates that the preferred transport pathway for neutral nicotine is transcellular. As the solution pH was decreased, and a greater fraction of nicotine became protonated, the transport of hydrophilic, charged nicotine species along the intercellular pathway was preferred.
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Affiliation(s)
- L L Chen
- Controlled Drug-Delivery Research Center, College of Pharmacy, Rutgers University, 41 Gordon Road, Suite D, Piscataway, NJ 08854-8067, USA
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142
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Huang TS, Lee CC, Chao Y, Shu CH, Chen LT, Chen LL, Chen MH, Yuan CC, Whang-Peng J. A novel podophyllotoxin-derived compound GL331 is more potent than its congener VP-16 in killing refractory cancer cells. Pharm Res 1999; 16:997-1002. [PMID: 10450922 DOI: 10.1023/a:1018971313256] [Citation(s) in RCA: 50] [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: 11/12/2022]
Abstract
PURPOSE GL331 is a new homolog of VP-16, and has demonstrated more efficacious anti-cancer activity in both the in vitro and in vivo lymphoma systems. To extensively explore GL331's clinical value, we furthermore evaluate the cytotoxicity and apoptosis-inducing activity of GL331 in several human cell lines from cancers that are not normally treated with VP-16. METHODS By MTT and clonogenic survival assays, the cytotoxicities of GL331 and VP-16 were evaluated in a variety of cell lines including nasopharyngeal, hepatocellular, gastric, colon, cervical, and neuroblastoma cancer types. Western blot analysis was performed to detect the MDR-1 level in these cell lines. By Annexin V-staining flow cytometry and detection of DNA ladders, the apoptosis-inducing activities of GL331 and VP-16 were also evaluated. RESULTS GL331 showed more efficacy than its congener VP-16 in killing cancer cells. The estimated ID50 of GL331 were 2.5 to 17-fold lowerthan those of VP-16. GL331 possessed more cell-killing activity even in MDR-1-overexpressing cell lines such as HCC36 and SW620. Its higher cytotoxicity could be attributed by the elevated ability to induce apoptotic cell death. CONCLUSION GL331's overriding drug resistance and higher cancer cell-killing activity suggest its superiority in clinical cancer therapy.
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Affiliation(s)
- T S Huang
- Cooperative Laboratory, Cancer Research Division, National Health Research Institutes, Taipei, Taiwan, Republic of China.
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143
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Chen LL, Whitty A, Lobb RR, Adams SP, Pepinsky RB. Multiple activation states of integrin alpha4beta1 detected through their different affinities for a small molecule ligand. J Biol Chem 1999; 274:13167-75. [PMID: 10224072 DOI: 10.1074/jbc.274.19.13167] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [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: 01/09/2023] Open
Abstract
We have used the highly specific alpha4beta1 inhibitor 4-((N'-2-methylphenyl)ureido)-phenylacetyl-leucine-aspartic acid-valine-proline (BIO1211) as a model LDV-containing ligand to study alpha4beta1 integrin-ligand interactions on Jurkat cells under diverse conditions that affect the activation state of alpha4beta1. Observed KD values for BIO1211 binding ranged from a value of 20-40 nM in the non-activated state of the integrin that exists in 1 mM Mg2+, 1 mM Ca2+ to 100 pM in the activated state seen in 2 mM Mn2+ to 18 pM when binding was measured after co-activation by 2 mM Mn2+ plus 10 microgram/ml of the integrin-activating monoclonal antibody TS2/16. The large range in KD values was governed almost exclusively by differences in the dissociation rates of the integrin-BIO1211 complex, which ranged from 0.17 x 10(-4) s-1 to >140 x 10(-4) s-1. Association rate constants varied only slightly under the same conditions, all falling in the narrow range from 0.9 to 2.7 x 10(6) M-1 s-1. The further increase in affinity observed upon co-activation by divalent cations and TS2/16 compared with that observed at saturating concentrations of metal ions or TS2/16 alone indicates that the mechanism by which these factors bring about activation are distinct and identified a previously unrecognized high affinity state on alpha4beta1 that had not been detected by conventional assay methods. Similar changes in affinity were observed when the binding properties of vascular cell adhesion molecule-1 and CS1 to alpha4beta1 were studied, indicating that the different affinity states detected with BIO1211 are an inherent property of the integrin.
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Affiliation(s)
- L L Chen
- Biogen, Inc., Cambridge, Massachusetts 02142, USA
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144
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Lin KC, Ateeq HS, Hsiung SH, Chong LT, Zimmerman CN, Castro A, Lee WC, Hammond CE, Kalkunte S, Chen LL, Pepinsky RB, Leone DR, Sprague AG, Abraham WM, Gill A, Lobb RR, Adams SP. Selective, tight-binding inhibitors of integrin alpha4beta1 that inhibit allergic airway responses. J Med Chem 1999; 42:920-34. [PMID: 10072689 DOI: 10.1021/jm980673g] [Citation(s) in RCA: 183] [Impact Index Per Article: 7.3] [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: 11/28/2022]
Abstract
Integrin alpha4beta1 mediates leukocyte recruitment, activation, mediator release, and apoptosis inhibition, and it plays a central role in inflammatory pathophysiology. High-affinity, selective inhibitors of alpha4beta1, based on the Leu-Asp-Val (LDV) sequence from the alternatively spliced connecting segment-1 (CS-1) peptide of cellular fibronectin, are described that employ a novel N-terminal peptide "cap" strategy. One inhibitor, BIO-1211, was approximately 10(6)-fold more potent than the starting peptide and exhibited tight-binding properties (koff = 1.4 x 10(-4) s-1, KD = 70 pM), a remarkable finding for a noncovalent, small-molecule inhibitor of a protein receptor. BIO-1211 was also 200-fold selective for the activated form of alpha4beta1, and it stimulated expression of ligand-induced epitopes on the integrin beta1 subunit, a property consistent with occupancy of the receptor's ligand-binding site. Pretreatment of allergic sheep with a 3-mg nebulized dose of BIO-1211 inhibited early and late airway responses following antigen challenge and prevented development of nonspecific airway hyperresponsiveness to carbachol. These results show that highly selective and potent small-molecule antagonists can be identified to integrins with primary specificity for peptide domains other than Arg-Gly-Asp (RGD); they confirm the generality of integrins as small molecule targets; and they validate alpha4beta1 as a therapeutic target for asthma.
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Affiliation(s)
- K c Lin
- Biogen Inc., 12 Cambridge Center, Cambridge, Massachusetts 02142, and Mount Sinai Medical Center, Miami Beach, Florida 33140, USA
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Shaw CK, Chen LL, Lee A, Lee TD. Distribution of HLA gene and haplotype frequencies in Taiwan: a comparative study among Min-nan, Hakka, Aborigines and Mainland Chinese. Tissue Antigens 1999; 53:51-64. [PMID: 10082431 DOI: 10.1034/j.1399-0039.1999.530106.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A total of 8,497 blood samples were typed for HLA-A, B, DR and DQ. Of these, 7,137 Min-nan, 714 Hakka, 535 Mainland Chinese (152 from North China, 211 from Middle China, and 172 from South China) and 111 Aborigines were randomly selected from Tzu Chi Taiwan Marrow Donor Registry (TCTMDR). Differences in HLA gene and antigen frequencies have been observed between various ethnic groups of the Chinese population in Taiwan. The phylogenic tree shows Taiwan Aborigines and Javanese cluster together; Min-nan shares a common cluster with Hakka, Southern Hans and Thai; and Northern Hans shares a cluster with Middle Hans. The separation between Northern/Middle and Southern Chinese Hans support the idea that Northern and Southern Chinese have different genetic background. Aborigines appeared to be quite distinct in the distribution of a majority of the class I and class II antigens. High frequency of HLA-A24 (60.4%) and relatively restricted HLA polymorphisms are noted in Aborigines. The HLA haplotypes with high frequency in Aborigines included A24-B60-DRB1*04, A24-B60-DRB1*14, A24-B48-DRB1*04, and A24-B48-DRB1*14, which are different from the other ethnic groups. Although the phylogenic tree separates Aborigines and Han Chinese populations, 4 out of 20 most common HLA-A, -B, and -DR haplotypes presented in both Aborigines and Han Chinese may reflect an ancient common origin or intermixture between early settlers of Han Chinese and Taiwan Aborigines. The results in this study are essentially a summary of the observed gene/haplotype frequencies and differences among various ethnic groups in Taiwan.
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Affiliation(s)
- C K Shaw
- Department of Public Health, Tzu Chi College of Medicine, Hualien, Taiwan
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146
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Chen LL, Peng SS. [The method of getting the prime diagnostic factors of anterior crossbite in early permanent dentition]. Shanghai Kou Qiang Yi Xue 1998; 7:157-9. [PMID: 15071654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
OBJECTIVE:We want to select the prime diagnostic factors of anterior corssibe which cna be used to identify the dental and skeletal anterior crossbite. METHODS: From 85 anterior crossbite patients in early permanent dentistion with accurate diagnosis we selected 70 cases to get the prime diagnostic factors by using stepwise discriminant analysis. They were checked by the other 15 cases, We could assess the effects of the factors by calculating their contribution rates. RESULTS: We get six factors: CoGn,AOBO,S'-Ptm',ANB,MPPP,Ramus Angle. CONCLUSION: They include the most information we need to indentify the dental or skeletal anterior crossbite.
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Affiliation(s)
- L L Chen
- Department of Orthodontics, School of Stomatology,Shanghai Second Medical University. Shanghai 200011,China
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147
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Christian DL, Chen LL, Scannell CH, Ferrando RE, Welch BS, Balmes JR. Ozone-induced inflammation is attenuated with multiday exposure. Am J Respir Crit Care Med 1998; 158:532-7. [PMID: 9700132 DOI: 10.1164/ajrccm.158.2.9709023] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.2] [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: 11/16/2022] Open
Abstract
It is well known that ozone (O3) causes acute lung inflammation. What is not known is whether there is progression of the inflammatory response in humans with repeated short-term exposures. Our study was designed to test the hypothesis that repeated exposures to a high-ambient concentration of O3 (0.2 ppm) over several days would cause more inflammation than a single exposure. Fifteen healthy volunteers were exposed in random fashion to 0.2 ppm ozone for 4 h on a single day and to 0.2 ppm O3 for 4 h on 4 consecutive days while exercising moderately for 30 min of each hour. Pulmonary function tests were obtained immediately before and after each 4-h exposure. Bronchoscopy was performed 20 h after the completion of each exposure arm to obtain bronchoalveolar lavage (BAL) for measurement of markers of inflammation. Our results show initial progression followed by attenuation of the acute physiologic response to O3 with repeated daily exposures. We found a significant difference in percent change in FEV1, FVC, and specific airway resistance (SRaw) across the single-day exposure when compared with the change across Day 4 of the 4-d exposure. Bronchial fraction (the first 15 ml of BAL return) and BAL were analyzed for the following end points: total and differential cell counts, total protein, lactate dehydrogenase (LDH), fibronectin, interleukin-6 (IL-6), interleukin-8 (IL-8), and granulocyte-macrophage colony-stimulating factor (GM-CSF). In the bronchial fraction the number of polymorphonuclear cells (PMN)s and fibronectin concentration were significantly decreased after 4-d exposure compared with single-day exposure. In BAL, significant decreases in the number of PMNs, fibronectin, and IL-6 were found after 4-d exposure versus single-day exposure. These results suggest that there is attenuation of the O3-induced inflammatory response in both proximal airways and distal lung with repeated daily exposures.
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Affiliation(s)
- D L Christian
- The Lung Biology Center, Center for Occupational and Environmental Health, and Medical Service, San Francisco General Hospital, University of California, San Francisco, California, USA
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148
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Lin S, Chen LL, Chien YW. Comparative pharmacokinetic and pharmacodynamic studies of human insulin and analogues in chronic diabetic Yucatan minipigs. J Pharmacol Exp Ther 1998; 286:959-66. [PMID: 9694956] [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: 02/08/2023] Open
Abstract
Pharmacokinetics and pharmacodynamics of insulin analogues were compared with human insulin in streptozotocin-induced chronic diabetic Yucatan minipigs. After overnight fasting, insulin or one of the insulin analogues (0.6 nmol/kg) in acid solutions (pH approximately 3.0) was administered to the minipigs s.c. The plasma insulin concentrations were then measured by radioimmunoassay at predetermined time intervals although blood glucose levels were monitored continuously. The mean (+/-S.E.) values of DeltaCmax (difference between peak and basal plasma insulin levels) were 598 (+/-21), 528 (+/-44), 176 (+/-21), 325 (+/-60) and 228 (+/-33) pM, respectively, for analogue AspB9GluB27, AspB9, GluB27, AspB28 and insulin. The differences in DeltaCmax values were statistically significant between AspB9GluB27 and insulin (P < .02), and between AspB9 and insulin (P < .01), but not between GluB27 or AspB28 and insulin. Moreover, the mean (+/-S.E.) values of DeltaAUC0-->6 (integrated area between plasma insulin concentration curve and basal level) were 1877 (+/-169), 1897 (+/-70), 485 (+/-36), 500 (+/-32) and 677 (+/-105) pM x hr, respectively, for AspB9GluB27, AspB9, GluB27, AspB28 and insulin. The differences in DeltaAUC0-->6 values were statistically significant between AspB9GluB27 and insulin (P < .05) and between AspB9 and insulin (P < .02), but not between GluB27 or AspB28 and insulin. However, there was no significant difference in the values of Deltanadir (difference between nadir and basal levels) and ABGC0-->12 (integrated area between blood glucose response curve and basal level) between insulin and various analogues. In conclusion, although the insulin analogues are different from human insulin in pharmacokinetics, they exhibit similar biological activity to human insulin in the streptozotocin-induced chronic diabetic minipigs.
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Affiliation(s)
- S Lin
- Controlled Drug-Delivery Research Center, College of Pharmacy, Rutgers University, Piscataway, New Jersey 08854-8067, USA
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149
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Chen LL, Lobb RR, Cuervo JH, Lin KC, Adams SP, Pepinsky RB. Identification of ligand binding sites on integrin alpha4beta1 through chemical cross-linking. Biochemistry 1998; 37:8743-53. [PMID: 9628736 DOI: 10.1021/bi980311a] [Citation(s) in RCA: 25] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We have used chemical cross-linking to identify sequences in integrin alpha4beta1 that are involved in its interactions with ligands. A recently described leucine-aspartic acid-valine (LDV)-based small molecule inhibitor of alpha4beta1 (BIO-1494), that contained a single reactive amino group for targeting the cross-linking, was used for these studies. The specificity of the interaction was defined by (i) the ability to block the interaction with a competitive inhibitor lacking the reactive group, (ii) the absolute requirement of divalent cations for cross-linking, and (iii) the lack of cross-linking to the functionally related integrin alpha4beta7. With ANB-NOS as the cross-linker, only the beta1 chain was labeled with BIO-1494, while with the more flexible cross-linker DSS both the alpha4 and beta1 chains were modified. Similar results were obtained when cross-linking was performed on K562 cells expressing alpha4beta1 but not on K562 cells expressing alpha2beta1. The site of cross-linking on the beta1 chain was localized by CNBr peptide mapping within residues 130-146, a region that contains the putative metal binding site DXSXS and for which analogous data had been generated with RGD binding to integrin alphaIIbbeta3. The striking similarity between the data we generated for an LDV ligand and published data for the RGD family supports the notion of a common ligand binding pocket formed by both integrin chains. The cross-linking strategy developed here should serve as a useful tool for studying alpha4beta1 function.
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Affiliation(s)
- L L Chen
- Biogen Inc., 14 Cambridge Center, Cambridge, Massachusetts 02142, USA
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150
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Abstract
A kinetic model was proposed to characterize the swelling phenomenon of polyacrylamide hydrogel and to quantify and predict the loading of insulin into the hydrogel by swelling. Polyacrylamide hydrogel and porcine insulin were used in the study. During swelling, the insulin concentration in the hydrogel was found to be higher than that in the loading solution, which could be attributed to ionization of the ionic networks, Donnan exclusion, and the possible ionic interactions between the anionic carboxylic pendants and cationic insulin. The experimental results demonstrated that the proposed kinetic model was able to describe the swelling kinetics of polyacrylamide hydrogel and the loading kinetics of insulin by using only two constants [input rate (Kin) and output rate (Kout)]. The experimental values of Kin and Kout were found to highly depend on the concentration of HCl. As medium pH declined (because of the addition of HCl), the degree of swelling decreased and the insulin loading amount in the hydrogel was reduced. A linear log-log function was observed between Kin and the volume fraction of HCl. The Kout values also decreased with the addition of HCl, but remained constant after more than 1% (v/v) of HCl (0.01 N) was added. The proposed model was able to characterize the swelling kinetics of polyacrylamide and predict the loading dose of insulin in the polyacrylamide hydrogel by swelling.
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Affiliation(s)
- L L Chen
- Controlled Drug-Delivery Research Center, College of Pharmacy, Rutgers University, Piscataway, New Jersey 08854, USA.
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