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Deng G, Zhang Y, Jin N, Michael M, Karathanasis S. ID: 151 Cathepsin S Expression in Mouse Obesity Models. J Thromb Haemost 2006. [DOI: 10.1111/j.1538-7836.2006.00151.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Li Y, Lin Z, Shi J, Qi Q, Deng G, Li Z, Wang X, Tian G, Chen H. Detection of Hong Kong 97-like H5N1 influenza viruses from eggs of Vietnamese waterfowl. Arch Virol 2006; 151:1615-24. [PMID: 16532371 DOI: 10.1007/s00705-006-0738-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2005] [Accepted: 01/30/2006] [Indexed: 10/24/2022]
Abstract
Three H5N1 influenza viruses were isolated from shell washes of duck and goose eggs confiscated from travelers coming from Vietnam. All eight gene segments of these viruses share high sequence identity with the H5N1 avian influenza viruses that caused outbreaks in poultry and humans in Hong Kong in 1997. Animal studies indicate that these isolated viruses are able to replicate in mouse lung and could be found in the organs of ducks without causing any clinical signs or death. However, the viruses are highly pathogenic for chickens. Although the source of these recently isolated Hong Kong 97-like H5N1 viruses is undetermined, their detection in the egg shell of duck and goose suggests that this particular genotype of H5N1 virus may have re-emerged in nature or may have been circulating continuously.
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Chen H, Deng G, Li Z, Tian G, Li Y, Jiao P, Zhang L, Liu Z, Webster RG, Yu K. The evolution of H5N1 influenza viruses in ducks in southern China. Proc Natl Acad Sci U S A 2004; 101:10452-7. [PMID: 15235128 PMCID: PMC478602 DOI: 10.1073/pnas.0403212101] [Citation(s) in RCA: 400] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The pathogenicity of avian H5N1 influenza viruses to mammals has been evolving since the mid-1980s. Here, we demonstrate that H5N1 influenza viruses, isolated from apparently healthy domestic ducks in mainland China from 1999 through 2002, were becoming progressively more pathogenic for mammals, and we present a hypothesis explaining the mechanism of this evolutionary direction. Twenty-one viruses isolated from apparently healthy ducks in southern China from 1999 through 2002 were confirmed to be H5N1 subtype influenza A viruses. These isolates are antigenically similar to A/Goose/Guangdong/1/96 (H5N1) virus, which was the source of the 1997 Hong Kong "bird flu" hemagglutinin gene, and all are highly pathogenic in chickens. The viruses form four pathotypes on the basis of their replication and lethality in mice. There is a clear temporal pattern in the progressively increasing pathogenicity of these isolates in the mammalian model. Five of six H5N1 isolates tested replicated in inoculated ducks and were shed from trachea or cloaca, but none caused disease signs or death. Phylogenetic analysis of the full genome indicated that most of the viruses are reassortants containing the A/Goose/Guangdong/1/96-like hemagglutinin gene and the other genes from unknown Eurasian avian influenza viruses. This study is a characterization of the H5N1 avian influenza viruses recently circulating in ducks in mainland China. Our findings suggest that immediate action is needed to prevent the transmission of highly pathogenic avian influenza viruses from the apparently healthy ducks into chickens or mammalian hosts.
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Siddique T, Hu P, Hentati A, Deng G, Hung WY, McInnis MG, Warren AC, Rimmler J, Antonarakis S, Pericak-Vance MA. A molecular genetic approach to amyotrophic lateral sclerosis. INTERNATIONAL JOURNAL OF NEUROLOGY 2002; 25-26:60-9. [PMID: 11980064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Disorders of the motor neurons may affect both the upper and lower neurons, primarily the lower motor neurons as in the spinal muscular atrophies are primarily the upper motor neurons as in the familial spastic paraplegias. Amyotrophic lateral sclerosis is a degenerative disorder of the motor neuron that results in paralysis and wasting of voluntary muscles. Large motor neurons in the cerebral cortex, brain stem and spinal cord degenerate or are lost. Hyaline inclusions may be seen in the cytoplasm of surviving motor neurons. Acute axonal degeneration of peripheral motor fibers occurs at all levels, including the distal axon. Subclinical involvement of the spinecerebellar tracts, posterior column and Clarke's column as well as loss of large neurons in the dorsal root ganglia and neurons of oculomotor nuclei has been reported. The average duration of life onset of symptoms of amyotrophic lateral sclerosis is three years and ninety per cent of patients died within 5 years. The basic mechanism of disease in amyotrophic lateral sclerosis remains unknown. There is no known treatment that will prevent, reverse or otherwise alter the course of the disease. Autosomal dominant and autosomal recessive forms of amyotrophic lateral sclerosis are genetic models of amyotrophic lateral sclerosis which may provide insight into the disease mechanism of sporadic amyotrophic lateral sclerosis, five to ten percent of adult cases of amyotrophic lateral sclerosis with early onset of symptoms and a more benign course. It is conceivable that both genetic and sporadic forms of amyotrophic lateral sclerosis result from failure of the same or similar neuronal mechanism triggered by defective genes and by an environment agent in sporadic amyotrophic lateral sclerosis.
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Deng G, Peng E, Gum J, Terdiman J, Sleisenger M, Kim YS. Methylation of hMLH1 promoter correlates with the gene silencing with a region-specific manner in colorectal cancer. Br J Cancer 2002; 86:574-9. [PMID: 11870540 PMCID: PMC2375277 DOI: 10.1038/sj.bjc.6600148] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2001] [Accepted: 09/28/2001] [Indexed: 12/15/2022] Open
Abstract
Microsatellite instability is present in over 80% of the hereditary non-polyposis colorectal carcinoma and about 15-20% of the sporadic cancer. Microsatellite instability is caused by the inactivation of the mismatch repair genes, such as primarily hMLH1, hMSH2. To study the mechanisms of the inactivation of mismatch repair genes in colorectal cancers, especially the region-specific methylation of hMLH1 promoter and its correlation with gene expression, we analysed microsatellite instability, expression and methylation of hMLH1 and loss of heterozygosity at hMLH1 locus in these samples. Microsatellite instability was present in 17 of 71 primary tumours of colorectal cancer, including 14 of 39 (36%) mucinous cancer and three of 32 (9%) non-mucinous cancer. Loss of hMLH1 and hMSH2 expression was detected in nine and three of 16 microsatellite instability tumours respectively. Methylation at CpG sites in a proximal region of hMLH1 promoter was detected in seven of nine tumours that showed no hMLH1 expression, while no methylation was present in normal mucosa and tumours which express hMLH1. However, methylation in the distal region was observed in all tissues including normal mucosa and hMLH1 expressing tumours. This observation indicates that methylation of hMLH1 promoter plays an important role in microsatellite instability with a region-specific manner in colorectal cancer. Loss of heterozygosity at hMLH1 locus was present in four of 17 cell lines and 16 of 54 tumours with normal hMLH1 status, while loss of heterozygosity was absent in all nine cell lines and nine tumours with abnormal hMLH1 status (mutation or loss of expression), showing loss of heterozygosity is not frequently involved in the inactivation of hMLH1 gene in sporadic colorectal cancer.
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Shang F, Deng G, Obin M, Wu CC, Gong X, Smith D, Laursen RA, Andley UP, Reddan JR, Taylor A. Ubiquitin-activating enzyme (E1) isoforms in lens epithelial cells: origin of translation, E2 specificity and cellular localization determined with novel site-specific antibodies. Exp Eye Res 2001; 73:827-36. [PMID: 11846513 DOI: 10.1006/exer.2001.1091] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Lens development and response to peroxide stress are associated with dramatic changes in protein ubiquitination, reflecting dynamic changes in activity of the ubiquitin-activating enzyme (E1). Two isoforms of E1 (E1A and E1B) have been identified in lens cells although only one E1 mRNA, containing three potential translational start sites, has been detected. Novel, site-specific antibodies to E1 were generated and the hypothesis that the two isoforms of E1 are translated from alternative initiation codons of a single mRNA was tested. Antibodies raised against E1A-N peptide (Met(1)to Cys(23)of E1A) reacted only with E1A by immunoblot and immunoprecipitation. Antibodies raised against E1B-N peptide (Met(1)to Glu(25)of E1B or Met(41)to Glu(65)of E1A) and E1AB-C peptide (His(1030)to Arg(1058)of E1A or His(990)to Arg(1018)of E1B) reacted with both E1A and E1B. These results indicate that (1) E1A and E1B contain the same C-terminal residues; (2) E1A contains the N terminal sequence of E1B; and (3) E1B does not contain the N terminal sequence of E1A. The two isoforms of lens E1 are therefore translated from a single mRNA. Specifically, E1A is translated from the first initiation codon, and E1B translated from the second initiation codon. E1A and E1B were affinity-purified, and their ability to 'charge' ubiquitin carrier proteins (E2s) with activated ubiquitin was compared in a cell-free system. E1A and E1B were indistinguishable with respect to charging different E2s. However, E1 immunolocalization studies with human lens epithelial cells indicate that E1A and E1B are preferentially localized to the nucleus and cytosol, respectively. This observation suggests that E1A and E1B ubiquitinate different proteins and serve different functions in intact cells.
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Deng G, Chen A, Pong E, Kim YS. Methylation in hMLH1 promoter interferes with its binding to transcription factor CBF and inhibits gene expression. Oncogene 2001; 20:7120-7. [PMID: 11704838 DOI: 10.1038/sj.onc.1204891] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2000] [Revised: 07/17/2001] [Accepted: 08/02/2001] [Indexed: 12/14/2022]
Abstract
Microsatellite instability (MSI) is caused by the dysfunction of mismatch repair genes, such as hMLH1, hMSH2. Loss of hMLH1 expression and methylation of CpG sites in hMLH1 promoter are frequently present in sporadic colorectal cancer with MSI. In this study, by transient transfection assay with constructs containing different lengths of hMLH1 promoter and a luciferase reporter gene, we located a proximal region of hMLH1 promoter, which plays a main role in regulating the gene. The fact that luciferase activities were high in all host cell lines regardless of their hMLH1 expression levels indicates that the transcription machinery is intact even in non-expressing cells. When hMLH1 promoter was in vitro methylated before transfection, the luciferase activities in the transfectants were significantly reduced. This observation indicates that methylation causes the inhibition of hMLH1 promoter activity. By electrophoretic mobility shift assay (EMSA), we identified a CCAAT box in this region, which specifically bound transcription factor CBF. Mutations in CCAAT box not only inhibited its binding to CBF factor, but also reduced its ability to drive the expression of luciferase gene. The role of CBF in activating transcription was further substantiated by inhibition of promoter activity with a plasmid expressing a dominant negative CBF-B mutant. Methylation at a CpG site two base pairs upstream of the CCAAT box inhibited the binding of CBF to CCAAT box. We conclude that methylation of an adjacent CpG site inhibits binding of the CBF transcription to the corresponding CCAAT box, and is one of the causes of hMLH1 gene silencing in colon cancer cells.
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MESH Headings
- Adaptor Proteins, Signal Transducing
- Adenocarcinoma/pathology
- Azacitidine/analogs & derivatives
- Azacitidine/pharmacology
- Binding Sites
- CCAAT-Binding Factor/metabolism
- Carrier Proteins
- Colorectal Neoplasms/pathology
- CpG Islands
- DNA Methylation/drug effects
- DNA, Neoplasm/chemistry
- DNA, Neoplasm/genetics
- Decitabine
- Electrophoresis, Polyacrylamide Gel
- Gene Expression Regulation/genetics
- Gene Expression Regulation, Neoplastic/drug effects
- Gene Expression Regulation, Neoplastic/genetics
- Gene Silencing
- Genes, Reporter
- Humans
- Luciferases/analysis
- Luciferases/genetics
- MutL Protein Homolog 1
- Neoplasm Proteins/biosynthesis
- Neoplasm Proteins/genetics
- Nuclear Proteins
- Promoter Regions, Genetic/genetics
- Protein Binding
- Recombinant Fusion Proteins/analysis
- Transcription, Genetic
- Transfection
- Tumor Cells, Cultured
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58
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Deng G, Curriden SA, Hu G, Czekay RP, Loskutoff DJ. Plasminogen activator inhibitor-1 regulates cell adhesion by binding to the somatomedin B domain of vitronectin. J Cell Physiol 2001; 189:23-33. [PMID: 11573201 DOI: 10.1002/jcp.1133] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Plasminogen activator inhibitor-1 (PAI-1) binds to the somatomedin B (SMB) domain of vitronectin. It inhibits the adhesion of U937 cells to vitronectin by competing with the urokinase receptor (uPAR; CD87) on these cells for binding to the same domain. Although the inhibitor also blocks integrin-mediated cell adhesion, the molecular basis of this effect is unclear. In this study, the effect of the inhibitor on the adhesion of a variety of cells (e.g., U937, MCF7, HT-1080, and HeLa) to vitronectin was assessed, and the importance of the SMB domain in these interactions was determined. Although PAI-1 blocked the adhesion of all of these cells to vitronectin-coated wells, it did not block adhesion to a variant of vitronectin which lacked the SMB domain. Interestingly, HT-1080 and U937 cells attached avidly to microtiter wells coated with purified recombinant SMB (which does not contain the RGD sequence), and this adhesion was again blocked by the inhibitor. These results affirm that PAI-1 can inhibit both uPAR- and integrin-mediated cell adhesion, and demonstrate that the SMB domain of vitronectin is required for these effects. They also show that multiple cell types can employ uPAR as an adhesion receptor. The use of purified recombinant SMB should help to further define this novel adhesive pathway, and to delineate its relationship with integrin-mediated adhesive events.
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Royle G, Deng G, Seiffert D, Loskutoff DJ. A method for defining binding sites involved in protein-protein interactions: analysis of the binding of plasminogen activator inhibitor 1 to the somatomedin domain of vitronectin. Anal Biochem 2001; 296:245-53. [PMID: 11554720 DOI: 10.1006/abio.2001.5316] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Plasminogen activator inhibitor type-1 (PAI-1) is bound to vitronectin (VN) in plasma and in the extracellular matrix. We previously employed a domain-swapping approach to show that the high-affinity binding site for PAI-1 in VN is contained within residues 12-30 in the amino-terminal somatomedin B (SMB) domain. In this study, we attempt to further delineate the location of this site by employing a novel approach that is based on the use of monoclonal antibodies (Mabs) together with site-directed mutagenesis. Six separate Mabs were identified that bound to the SMB domain and competed with PAI-1 for binding to VN. The relative affinity of each of the Mabs, and of PAI-1 itself, for binding to individual variants of SMB (prepared by alanine scanning mutagenesis), was then determined and compared in competitive binding experiments. Three separate, partially overlapping Mab epitopes within SMB were defined by these studies, and the PAI-1 binding site was localized to the region between residues 24 and 37. When considered together with the domain swapping data, these studies suggest that the PAI-1 binding site is contained within a common seven-residue region (i.e., residues 24-30) in the SMB domain.
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60
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Deng G, Wang A. [Retrospective analysis of 15 patients with fungal septicaemia]. ZHONGHUA NEI KE ZA ZHI 2001; 40:594-6. [PMID: 11758238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE Study on the early diagnosis, antifungal therapy, and prophylaxis for fungemia. METHOD Retrospective study of the clinical features, treatment and outcome of 15 patients with fungemia from August 1992 to September 2000 at Peking Union Medical College Hospital. RESULTS The patients' ages ranged from 25 days (1 newborn) to 72 years (mean: 54.5 years in 14 patients); 11 were male. The length of hospitalization before fungemia varied from 7 days to 12 months (median: 1.5 months) in 14 patients who fulfilled criteria for nosocomial fungemia, another one with fungemia occurred outside of hospital. The main underlying conditions were: malignant disease (cancer, leukemia and acute aplastic anemia) in 10 patients (66.7%), infections following abdominal surgery in 2 patients (13.3%), trauma in 1 patient, rheumatic heart disease in 1 patient and 1 newborn. In this group the risk factors for fungemia included: prior antimicrobial therapy (14 of 15, 93.3%), steroids/cytotoxic chemotherapy (11 of 15, 73.3%), neutropenia (4/15, 26.7%), central venous catheterization and hyperalimentation (2 of 15, 13.3%). There were two or more risk factors in each of 11 patients. Fungal species isolated from 15 patients were: C. albicans (in 4), C. tropicalis (in 3), C. parapsilosis (in 3), C. sake (in 1), Trichosporon beigelii (in 1) and Yeast-like fungus (in 3). Before or during of fungemia, there were abnormal pulmonary signs or chest roentgenogram in 11 (73.3%), thrush in 2 (13.3%), enteritis in 2 (13.3%), urinary tract infection in 2 (13.3%) and endocarditis in 2 (13.3%). The overall mortality was 53.3% (8 of 15) and was 26.7%(4 of 15) duo to fungemia. Out of 7 survived patients, 4 were cured, 3 with fluconazole (length of therapy: 3-5 weeks) and 1 with a combination therapy of amphotericin B plus fluconazole (length of therapy: 3 months), other 3 were improved with fluconazole or amphotericin B (length of therapy: > 2 weeks). During the antifungal therapy, 2 patients with the complication of fungal endocarditis underwent surgical removal of vegetation on the infected valves. CONCLUSION In this study, the most frequent infectious agents were Candida albicans and non-albicans Candida species. Early diagnosis is of importance to guide appropriate antifungal therapy and reduce mortality.
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Ling S, Deng G, Ives HE, Chatterjee K, Rubanyi GM, Komesaroff PA, Sudhir K. Estrogen inhibits mechanical strain-induced mitogenesis in human vascular smooth muscle cells via down-regulation of Sp-1. Cardiovasc Res 2001; 50:108-14. [PMID: 11282083 DOI: 10.1016/s0008-6363(01)00200-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE The cellular basis of the cardioprotective effects of estrogen are largely unknown. An inhibitory effect on vascular smooth muscle (VSM) growth has been proposed. We examined the effect of 17beta-estradiol (E2) on mechanical strain-induced mitogenesis in human fetal VSM cells. METHODS AND RESULTS Cells were grown on fibronectin-coated plates with silicone-elastomer bottoms, and exposed to cyclic mechanical strain (60 cycles/min), with and without E2 (1 nmol/l), for 48 h. [3H]-Thymidine incorporation was measured during the last 6 h. Strain induced 1.5-2 fold increases in DNA synthesis that were attenuated by antibodies to platelet-derived growth factor (PDGF) AA and BB. Strain also induced increases both in mRNA and protein levels of Sp-1, a transcription factor that binds to the PDGF-A gene promoter site. E2 attenuated strain-induced mitogenesis, and also increases in mRNA and protein levels of Sp-1. The estrogen receptor (ER) antagonist ICI 182,780 (100 nmol/l) reversed the inhibitory effect of E2 on strain-induced increases in DNA synthesis and Sp-1 protein. RT-PCR analysis showed presence of both ER-alpha and -beta in these cells. CONCLUSIONS Estrogen inhibits strain-induced mitogenesis in human VSM cells via an ER mediated process involving down-regulation of the transcription factor Sp-1.
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MESH Headings
- Cell Culture Techniques
- Cell Division/physiology
- DNA/biosynthesis
- Down-Regulation
- Estradiol/pharmacology
- Female
- Humans
- Mitosis/drug effects
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Platelet-Derived Growth Factor/genetics
- Platelet-Derived Growth Factor/physiology
- RNA, Messenger/genetics
- Receptors, Estrogen/genetics
- Receptors, Estrogen/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Sp1 Transcription Factor/metabolism
- Stress, Mechanical
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62
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Kim YS, Gum JR, Crawley SC, Deng G, Ho JJ. Mucin gene and antigen expression in biliopancreatic carcinogenesis. Ann Oncol 2001; 10 Suppl 4:51-5. [PMID: 10436785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Abstract
Mucins are high molecular weight glycoproteins which are heavily glycosylated with many carbohydrate side chains. In epithelial cancers such as biliopancreatic cancer, both quantitative and qualitative alterations in carbohydrate and polypeptide moieties of mucin glycoproteins occur. These changes in mucin glycoproteins are one of the most common phenotypic markers of biliopancreatic carcinogenesis and may play an important pathobiological role. The expression of some of the sialylated carbohydrate antigens appears to correlate with a poor prognosis and increased metastatic potential in biliopancreatic cancer. The increased exposure of peptide epitopes of mucin glycoproteins in biliopancreatic cancer appears to be due to either abnormal glycosylation and/or altered levels of mucin gene transcription. In addition, dysregulation of tissue specific mucin gene expression occurs in biliopancreatic cancer. This information is currently being exploited for further elucidation of the molecular mechanisms involved in carcinogenesis, tumor progression and metastasis, and the development of novel methods of diagnosis and therapy of biliopancreatic cancer.
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63
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Deng G, Chow D, Sanyal G. Quantitative determination of saccharide surfactants in protein samples by liquid chromatography coupled to electrospray ionization mass spectrometry. Anal Biochem 2001; 289:124-9. [PMID: 11161305 DOI: 10.1006/abio.2000.4939] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A direct and highly selective method, combining liquid chromatography (LC) with electrospray ionization mass spectrometry (ESI-MS), has been developed for quantifying saccharide surfactants. Saccharide surfactants, such as n-octyl-beta-d-glucopyranoside (NOG), are widely used to solubilize or refold membrane-bound or lipophilic proteins. In the present study, we have developed an LC-MS method to quantify NOG in protein samples. Protein-bound NOG was completely dissociated from proteins by reversed-phase LC, allowing the total amount of saccharide surfactant in protein samples to be quantified by MS. A chemical analog of NOG was used as an internal standard for improving the reproducibility of the method. Linearity was found in the range of 10 microg/mL-1.0 mg/mL NOG concentrations. Seven major surfactant oligomeric ions were detected under the ionization conditions applied and their relative abundance was essentially unchanged over the range of 0.05-1.0 mg/mL NOG concentrations. Consequently, ions with characteristic mass-to-charge ratios could be used for quantification of NOG. Analytical accuracy of the method was examined by determining the amounts of NOG recovered from apolipoprotein A-I and myoglobin samples spiked with NOG.
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64
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Deng D, Deng G, Lü Y. [Analysis of the methylation in CpG island by denaturing high-performance liquid chromatography]. ZHONGHUA YI XUE ZA ZHI 2001; 81:158-61. [PMID: 11798868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To establish a new approach for analyzing methylation circumventing the limitations of the existing methods. METHODS A region containing CpG sites in mismatch repair gene hMLH1 promoter was amplified by strand-specific polymerase chain reaction (PCR) after sodium bisulfite treatment. The retention time of the PCR product at partially denaturing temperature was determined by denaturing high-performance liquid chromatography (DHPLC). The methylation status obtained by DHPLC was proved by comparing it with that from sodium bisulfite-restriction enzyme digestion. RESULTS Methylation of hMLH1 promoter from a colorectal cancer cell line RKO and a gastric cancer cell line PACM82 was analyzed by DHPLC. The retention time of the PCR product from RKO was obviously longer than that from PACM82 (6.7 min vs. 6.2 min). Thus, it was concluded that the hMLH1 promoter from RKO was methylated, while that from PACM82 was not, since the longer retaining time of RKO was due to the higher C/G content after sodium bisulfite treatment. The results from DHPLC were consistent with those from sodium bisulfite-restriction enzyme digestion. CONCLUSION DHPLC method is a rapid and reliable approach for analyzing methylation in CpG island of the sequence of interest.
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65
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Zhang SY, Deng G, Li ZF, Cao SK, Zhou QF. Palladium complexes of side-chain liquid crystal polymers with T-shaped two-dimensional mesogenic units. POLYM ADVAN TECHNOL 2001. [DOI: 10.1002/pat.98] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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66
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Lin JH, Deng G, Huang Q, Morser J. KIAP, a novel member of the inhibitor of apoptosis protein family. Biochem Biophys Res Commun 2000; 279:820-31. [PMID: 11162435 DOI: 10.1006/bbrc.2000.4027] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have identified a novel human gene, kiap (kidney inhibitor of apoptosis protein) that encodes a single BIR domain and a RING zinc finger domain. kiap has been assigned to the q13.3 region of human chromosome 20 by fluorescent in situ hybridization analysis. Northern blot analysis indicates that KIAP is expressed mainly in placenta, lymph node and fetal kidney. In this report, we show that overexpression of KIAP blocks apoptosis induced by menadione or by overexpression of BAX. In addition, we show that overexpression of KIAP enhances apoptosis induced by etoposide, and, that KIAP fails to block apoptosis induced by overexpression of Fas. Thus, KIAP, a new member of the inhibitor of apoptosis protein (IAP) family, has pleiotropic effects on apoptosis induced by various stimuli.
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67
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Homey B, Dieu-Nosjean MC, Wiesenborn A, Massacrier C, Pin JJ, Oldham E, Catron D, Buchanan ME, Müller A, deWaal Malefyt R, Deng G, Orozco R, Ruzicka T, Lehmann P, Lebecque S, Caux C, Zlotnik A. Up-regulation of macrophage inflammatory protein-3 alpha/CCL20 and CC chemokine receptor 6 in psoriasis. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 164:6621-32. [PMID: 10843722 DOI: 10.4049/jimmunol.164.12.6621] [Citation(s) in RCA: 436] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Autoimmunity plays a key role in the immunopathogenesis of psoriasis; however, little is known about the recruitment of pathogenic cells to skin lesions. We report here that the CC chemokine, macrophage inflammatory protein-3 alpha, recently renamed CCL20, and its receptor CCR6 are markedly up-regulated in psoriasis. CCL20-expressing keratinocytes colocalize with skin-infiltrating T cells in lesional psoriatic skin. PBMCs derived from psoriatic patients show significantly increased CCR6 mRNA levels. Moreover, skin-homing CLA+ memory T cells express high levels of surface CCR6. Furthermore, the expression of CCR6 mRNA is 100- to 1000-fold higher on sorted CLA+ memory T cells than other chemokine receptors, including CXCR1, CXCR2, CXCR3, CCR2, CCR3, and CCR5. In vitro, CCL20 attracted skin-homing CLA+ T cells of both normal and psoriatic donors; however, psoriatic lymphocytes responded to lower concentrations of chemokine and showed higher chemotactic responses. Using ELISA as well as real-time quantitative PCR, we show that cultured primary keratinocytes, dermal fibroblasts, and dermal microvascular endothelial and dendritic cells are major sources of CCL20, and that the expression of this chemokine can be induced by proinflammatory mediators such as TNF-alpha/IL-1 beta, CD40 ligand, IFN-gamma, or IL-17. Taken together, these findings strongly suggest that CCL20/CCR6 may play a role in the recruitment of T cells to lesional psoriatic skin.
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68
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Glenn CC, Deng G, Michaelis RC, Tarleton J, Phelan MC, Surh L, Yang TP, Driscoll DJ. DNA methylation analysis with respect to prenatal diagnosis of the Angelman and Prader-Willi syndromes and imprinting. Prenat Diagn 2000; 20:300-6. [PMID: 10740202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
The Angelman (AS) and Prader-Willi syndromes (PWS) are clinically distinct neurobehavioural syndromes resulting from loss of maternal (AS) or paternal contributions (PWS) of imprinted genes within the chromosomal 15q11-q13 region. The molecular diagnosis of both syndromes can be made by a variety of techniques, including DNA methylation, DNA polymorphism and molecular cytogenetic analyses. DNA methylation analysis at three major loci (ZNF127, PW71 and 5' SNRPN) has been successfully used for the postnatal diagnosis of AS and PWS. Methylation analysis, in contrast to other techniques, can reliably be used to diagnose all three major molecular classes (deletion, uniparental disomy and imprinting mutation) of PWS, and three of the four major classes of AS. In this study we demonstrate that methylation analysis can also be successfully used in prenatal diagnosis, by examining specimens obtained from amniocentesis and chorionic villus sampling. Correct prenatal diagnoses were obtained in 24 out of 24 samples using the 5' SNRPN locus; 4 out of 15 using the ZNF127 locus; and 10 out of 18 using the PW71 locus. Therefore, our data indicate that although the DNA methylation imprints of ZNF127 and 5' SNRPN arise in the germline and are present in brain, only 5' SNRPN maintains the imprint in tissues suitable for the prenatal diagnosis of AS and PWS.
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Deng G, Kim YS. Quantitation of erbB-2 gene copy number in breast cancer by an improved polymerase chain reaction (PCR) technique, competitively differential PCR. Breast Cancer Res Treat 1999; 58:213-7. [PMID: 10718483 DOI: 10.1023/a:1006367700783] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A new method of measuring gene copy number in small samples of DNA was used to measure amplification of the erbB-2 gene and a reference gene in breast cancers. The method, termed 'competitively differential polymerase chain reaction' (CD-PCR), combines the advantages of two other techniques for measuring amplification by PCR, namely differential PCR (D-PCR) and competitive PCR (C-PCR). The CD-PCR methodology was evaluated for sensitivity and specificity by comparing amplification measured by CD-PCR with that obtained by fluorescence in situ hybridization (FISH), C-PCR, and Southern blotting analysis. CD-PCR analysis proved to be an accurate predictor of amplification. CD-PCR also overcomes the problems involved in variation of PCR efficiencies and DNA concentrations in tumor samples, and the problems caused by the plateau effect in PCR.
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Deng G, Su JH, Ivins KJ, Van Houten B, Cotman CW. Bcl-2 facilitates recovery from DNA damage after oxidative stress. Exp Neurol 1999; 159:309-18. [PMID: 10486199 DOI: 10.1006/exnr.1999.7145] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Oxidative stress is a major factor affecting the brain during aging and neurodegenerative diseases such as Alzheimer's disease (AD). Understanding the mechanisms by which neurons can be protected from oxidative stress, therefore, is critical for the prevention and treatment of such degeneration. Previous studies have shown that bcl-2 expression is increased in neurons with DNA damage in AD and bcl-2 has an antioxidant effect. The goal of this study is to document the effects of oxidative insults on mitochondrial and nuclear DNA in PC12 cells and determine the extent to which bcl-2 prevents damage or facilitates repair. Using extralong PCR to amplify nuclear and mitochondrial DNA, the time course of DNA damage and repair was determined. Within minutes after exposure of cells to low concentrations of hydrogen peroxide and peroxynitrite, significant mitochondrial and nuclear DNA damage was evident. Mitochondrial DNA was damaged to a greater degree than nuclear DNA. Expression of bcl-2 in PC12 cells inhibited nitric oxide donor (sodium nitroprusside)- and peroxynitrite-induced cell death. Although oxidative insults caused both genomic and mitochondrial DNA damage in cells expressing bcl-2, recovery from DNA damage was accelerated in these cells. These results suggest that neuronal up-regulation of bcl-2 may facilitate DNA repair after oxidative stress.
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Vaziri ND, Deng G, Liang K. Hepatic HDL receptor, SR-B1 and Apo A-I expression in chronic renal failure. Nephrol Dial Transplant 1999; 14:1462-6. [PMID: 10383008 DOI: 10.1093/ndt/14.6.1462] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Chronic renal failure (CRF) is associated with hypertriglyceridaemia and depressed plasma high-density lipoprotein (HDL)-cholesterol and apolipoprotein A-I (Apo A-I) concentrations. Uraemic hypertriglyceridaemia is due, in part, to lipoprotein lipase and hepatic lipase deficiencies, which are causally linked to excess parathormone (PTH). This study was designed to test the hypothesis that depressed plasma concentration and abnormal composition of HDL in CRF may be due to dysregulation of hepatic expression of Apo A-I and/or the newly discovered HDL receptor. METHODS Hepatic Apo A-I and HDL receptor mRNA abundance (Northern blot), and HDL receptor protein mass (Western blot) were determined in CRF rats (5/6 nephrectomy), parathyroidectomized CRF rats (CRF-PTx) and sham-operated controls. RESULTS The CRF group exhibited normal hepatic HDL receptor mRNA and HDL receptor protein abundance coupled with reduced hepatic Apo A-I mRNA. Hepatic Apo A-I mRNA, HDL receptor mRNA and protein abundance were not affected by PTx. CONCLUSIONS CRF results in the down-regulation of hepatic Apo A-I gene expression, which accounts for the known reduction in plasma Apo A-I concentration. However, CRF does not affect HDL receptor mRNA or protein expression in this model. Neither Apo A-I nor HDL receptor expression were modified by PTx in CRF rats.
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Deng G, Chen A, Hong J, Chae HS, Kim YS. Methylation of CpG in a small region of the hMLH1 promoter invariably correlates with the absence of gene expression. Cancer Res 1999; 59:2029-33. [PMID: 10232580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Microsatellite instability (MSI) has been described in tumors from patients with hereditary nonpolyposis colorectal cancer, sporadic colorectal cancer, and other types of cancers. MSI is caused by the dysfunction of mismatch repairs genes. Loss of expression and mutation in one of the major mismatch repair genes, hMLH1, and the methylation of CpG sites in its promoter occur frequently in primary tumors and cell lines of colorectal cancer with MSI. To understand the mechanisms involved in the silencing of hMLH1 expression by methylation, we examined the methylation status of all CpG sites in the hMLH1 promoter in 24 colorectal cancer cell lines by the NaHSO3-sequencing method. We identified a small proximal region (-248 to -178, relative to the transcription start site) in the promoter in which the methylation status invariably correlates with the lack of hMLH1 expression. This correlation was further supported by the observation that cell lines that showed methylation-suppressed hMLH1 expression can be induced to reexpress hMLH1 by a methyl transferase inhibitor, 5-aza-2'-deoxycytidine, and the small region that we identified exhibited significant demethylation in all cell lines examined.
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Sun M, Liu Y, Liu W, Deng G, Tang W, Jiang Z. [Lactulose mannitol ratio in patients after operation]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 1999; 37:298-300. [PMID: 11829845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To study lactulose (lactulose, L) and mannitol (mannitol, M) ratio in urine following operation and investigate the correlation between severity of stress and L/M ratio. METHODS 20 patients who had received operation were enrolled and each patient was evaluated by APACH II scores. L/M permeability study was performed before the operation and 5 and 10 days after the operation. The L and M concentration was analyzed by HPLC with pulsed electrochemical detection (HPLC-PED). The correlation between L/M ratio and the severity of surgical stress were related. RESULTS The L/M ratio before the operation was (0.023 +/- 0.002), increased to (0.042 +/- 0.005) in the 5th post-operative day (P < 0.01), and then returned to (0.024 +/- 0.002) (P > 0.05) compared with pre-operation in the 10th Post-operation. A significant correlation between the severity of stress and the L/M ratio was observed (r = 0.762). CONCLUSIONS The L/M ratio was increased 5 days after the operation and the L/M ratio was correlated with severity of operative stress.
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Abstract
Based on the scientific literature, there are several molecular markers which might be used for the prognosis of breast cancer. Possible molecular prognostic markers are: BRCA-1, BRCA-2, p53, erbB oncogenes, loss of heterozygosity (LOH), chromosomal aberrations, microsatellite instability, transforming growth factor alpha (TGFalpha), and the multiple drug resistance (MDR) gene. In this chapter, we discuss the possible role of these prognostic markers in breast cancer.
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Kim Y, Gum J, Crawley S, Deng G, Ho J. Mucin gene and antigen expression in biliopancreatic carcinogenesis. Ann Oncol 1999. [DOI: 10.1093/annonc/10.suppl_4.s51] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Abstract
Type I plasminogen activator inhibitor (PAI-1) is the primary inhibitor of tissue- and urokinase-type plasminogen activators. It circulates in plasma complexed with vitronectin (VN), the primary PAI-1 binding protein. The somatomedin B (SMB) domain of VN contains both the high affinity PAI-1 binding site and the specific site for urokinase plasminogen activator receptor (uPAR). PAI-1 is able to regulate uPAR-mediated cell adhesion by competing with uPAR for VN binding. Binding of PAI-1 to SMD may also affect integrin-mediated cell adhesion to VN by hindering integrin binding to the RGD sequence adjacent to the uPAR binding site.
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Deng G, Jiang Z, Liu Y, He G, Xu Y. [Dietary fiber protects intestinal structure and barrier function]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 1998; 36:759-62. [PMID: 11825519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To evaluate the effect of dietary fiber on intestinal structure and barrier function of 5-fluorouracil (5-Fu) challenged rat. METHOD Thirty Wistar rats were divided randomly into three groups (10 each group): Chow, enteric nutrition (EN), and EN + Fiber group. Both EN and EN + Fiber group were isonitrogenic and isocaloric. The rats kept their diet respectively for 8 days. 5-Fu was injected intraperitoneally on day 4 postoperatively. Intestinal permeability (L/M) was measured respectively on day 3 and day 7. On day 8, the bacterial translation, wet weight and mucous thickness of both small intestine and colon and the villus height of small intestine were measured. The rats were weighted before and after experiment respectively. RESULT The body weight loss of the EN + Fiber group (-3.1 +/- 3.4 g) was less than that of the EN group (-6.6 +/- 5.2 g) (P < 0.05), whereas the Chow group gained body weight (4.9 +/- 4.3 g) (P < 0.01 when compared with EN and EN + Fiber group). The parameters of intestinal structures of the EN + Fiber group was superior to the EN group (P < 0.05). The L/M of both EN + Fiber (from 0.0265 +/- 0.0073 to 0.0274 +/- 0.0068) and the Chow group (from 0.0268 +/- 0.0039 to 0.0281 +/- 0.0044) was unchanged (P > 0.05 for both) after 5-Fu challenged, whereas that of the EN group increased (from 0.0289 +/- 0.0070 to 0.0331 +/- 0.0084) (P < 0.01). The incidence of bacterial translocation to MLN of both EN + Fiber group and the Chow group (20%) was lower than that of the EN group (70%) (P < 0.05). CONCLUSION The dietary fiber protects the intestinal structure and barrier function of 5-Fu challenged rats.
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Cao LC, Deng G, Boevé ER, de Bruijn WC, de Water R, Verkoelen CF, Romijn JC, Schröder FH. Zeta potential measurement and particle size analysis for a better understanding of urinary inhibitors of calcium oxalate crystallization. SCANNING MICROSCOPY 1998; 10:401-11; discussion 412-4. [PMID: 9813619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
To better understand urinary inhibitors of calcium oxalate crystallization, both zeta potential measurement and particle size analysis were chosen to illustrate: (1) the potential therapeutic efficacy of G872, a semi-synthetic sulfated polysaccharide, in stone prevention; and (2) the relative contribution of various urinary fractions ¿e.g., ultrafiltered urine (UFU), Tamm-Horsfall protein (THP), urinary polyanions precipitated with cetylpyridinium chloride (CPC), urinary macromolecular substances with different concentration ratios (UMS10,50,90 and UMS'10,50,90) and THP-free urine (THPFU)¿ to total urinary inhibitory activity. The results showed: (1) addition of G872 significantly enhances urinary inhibitory activity and negative zeta potential values; (2) re-addition of the CPC to UFU completely restores urinary inhibitory activity; and (3) artificial urines prepared by mixing UMS'10,50,90 from THPFU with UFU differed in inhibitory activity from that prepared by mixing UMS10,50,90 from a pooled normal urine with UFU. Based on these experimental results, the following speculations can be made: (1) normal human urines are considered to be a protective colloidal system; (2) urinary inhibitory activity originates mainly from CPC and/or UMS; (3) normal THP is a protective material to maintain urinary inhibitory activity; and (4) mutual interaction between urinary inhibitors may change the total urinary inhibitory activity.
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de Water R, Boevé ER, van Miert PP, Deng G, Cao LC, Stijnen T, de Bruijn WC, Schröder FH. Experimental nephrolithiasis in rats: the effect of ethylene glycol and vitamin D3 on the induction of renal calcium oxalate crystals. SCANNING MICROSCOPY 1998; 10:591-601; discussion 601-3. [PMID: 9813634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Using ethylene glycol (EG) and vitamin D3 as crystal-inducing diet (CID) in rats, we investigated the effect of the dosage of EG on the generation of chronic calcium oxalate (CaOx) nephrolithiasis. We collected weekly 24 hour urines and measured herein the amount of oxalate, calcium, glycosaminoglycans (GAG's), creatinine, protein, alkaline phosphatase (AP), gamma-glutamyl transpeptidase (gamma-GT), and N-acetyl-beta-glucosaminidase (NAG). The potential of these urines to inhibit crystal growth and agglomeration was also evaluated. After four weeks, the kidneys were screened by histology and radiography for the presence of CaOx crystals and the amount of kidney-associated oxalate was biochemically measured. Using 0.5 vol.% EG, only a part of the rats showed CaOx deposition in the renal cortex and/or medulla, without obvious differences between Wistar and Sprague-Dawley (SD) rats. If a dietary EG concentration of 0.75, 1.0, or 1.5 vol.% was used, the amount of kidney-associated oxalate was proportionally higher and CaOx crystal formation was consistently found in all rats. Most crystals were encountered in the cortex, whereas in the medulla and the papillary region, crystals were only occasionally detected. From these data, we conclude that in the chronic rat model, based on EG and vitamin D3, a consistent deposition of CaOx crystals is obtained using a EG concentration of at least 0.75%.
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Deng G, Laursen RA. Isolation and characterization of an antifreeze protein from the longhorn sculpin, Myoxocephalus octodecimspinosis. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1388:305-14. [PMID: 9858755 DOI: 10.1016/s0167-4838(98)00180-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new type of antifreeze protein was isolated from the serum of the longhorn sculpin, Myoxocephalus octodecimspinosis, by gel filtration and high-performance liquid chromatography. This protein (LS-12) exhibits freezing point depression activity (thermal hysteresis) and ice crystal modification properties similar to those seen for other types of fish antifreeze polypeptide, except that ice crystals grow as hexagonal trapezohedra in the presence of LS-12, rather than hexagonal bipyramids usually seen. Ice crystal etching studies demonstrate that LS-12 does not bind to the hexagonal bipyramidal or secondary prism surfaces reported for the antifreeze polypeptides from winter flounder and shorthorn sculpin, respectively. Circular dichroism studies indicate that LS-12 has an alpha-helix content of about 60% at 1 degreesC, which is in good agreement with a value of about 70% predicted from the amino acid sequence. Limited proteolysis studies and further analysis of the amino acid sequence suggest that LS-12 consists of four amphipathic alpha-helices of similar length which are folded into a four-helix bundle. Based on its size (Mr=12299) and predicted tertiary structure, LS-12 can be regarded as the first example of a new class (type IV) of fish antifreeze protein.
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Deng G, Matute C, Kumar CK, Fogarty DJ, Miledi R. Cloning and expression of a P2y purinoceptor from the adult bovine corpus callosum. Neurobiol Dis 1998; 5:259-70. [PMID: 9848096 DOI: 10.1006/nbdi.1998.0197] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We have isolated an ATP receptor clone by screening a bovine corpus callosum cDNA library. The clone includes one open reading frame encoding for a protein of 373 amino acid residues (42 kDa) which belongs to the G-protein-coupled receptor superfamily. In Xenopus oocytes, this clone expressed an ATP receptor that triggered an oscillatory current in response to ATP (EC50 approximately 20 microM). This current may have resulted from the activation of phospholipase C, the formation of inositol trisphosphate, and the release of Ca2+, which then opens Cl- channels. The order of potency for ATP receptor agonists was 2-MeSATP approximately ATP >> alpha, beta-MeATP > adenosine, and UTP was ineffective, a pharmacological profile consistent with that of a P2y purinoceptor. Northern blot analysis of mRNAs from various bovine brain tissues showed that the gene is expressed in the cerebellum, medulla, corpus callosum, hippocampus, superior colliculus, frontal cortex, and retina. In situ RT-PCR showed transcripts of the gene in many glial cells and endothelial cells of the corpus callosum. The cloned receptor may play an important role in neuron-glial signaling under normal and pathological conditions.
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Torp R, Su JH, Deng G, Cotman CW. GADD45 is induced in Alzheimer's disease, and protects against apoptosis in vitro. Neurobiol Dis 1998; 5:245-52. [PMID: 9848094 DOI: 10.1006/nbdi.1998.0201] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Expression of the growth arrest DNA damage-inducible protein, GADD45, has recently been reported to be induced by a wide range of stimuli, especially those that produce a high level of base pair damage. We have investigated the expression of GADD45 in brain tissue obtained from patients suffering from Alzheimer's disease (AD). Our results demonstrate that many neurons express the GADD45 protein, and that expression of this protein in neurons is associated with expression of the anti-apoptotic protein Bcl-2, and the presence of DNA damage, but not closely associated with tangle-bearing neurons. Additionally, cell lines overexpressing this protein confer resistance to apoptosis induced by DNA damage agent, suggesting that this protein may participate in cell survival mechanisms.
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Mustafa W, Zhu J, Deng G, Diab A, Link H, Frithiof L, Klinge B. Augmented levels of macrophage and Th1 cell-related cytokine mRNA in submandibular glands of MRL/lpr mice with autoimmune sialoadenitis. Clin Exp Immunol 1998; 112:389-96. [PMID: 9649206 PMCID: PMC1905000 DOI: 10.1046/j.1365-2249.1998.00609.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
MRL/Mp-lpr/lpr (MRL/lpr) mice spontaneously develop destructive inflammation of the salivary and lachrymal glands resembling Sjögren's syndrome (SS), representing an animal model to study this disease. We used in situ hybridization with synthetic radiolabelled oligonucleotide probes to examine expression of mRNA encoding pro- and anti-inflammatory cytokines in submandibular glands of 2, 3, 4 and 5-month-old MRL/lpr mice. Phenotypic composition of submandibular gland infiltrates was evaluated by immunohistochemistry. Cells expressing tumour necrosis factor-alpha (TNF-alpha), IL-1beta, IL-6 and IL-12 mRNA were strongly up-regulated at about the time of onset of sialoadenitis, suggesting a role of these cytokines in development of the disease. Interferon-gamma (IFN-gamma) and cytolysin mRNA-expressing cells were gradually up-regulated over the disease course up to 5 months of age, the time when sialoadenitis is at its height, favouring a role of these cytokines in progression of the disease as well. Low levels of IL-10 and transforming growth factor-beta (TGF-beta) mRNA-expressing cells were observed at 2, 3 and 4 months of age, and were almost undetectable at 5 months. Maximum levels of CD4+, CD8+ and interdigitating/dendritic cells, as well as of MHC class II and MHC class I expression were seen at 3 months, with CD4+ outnumbering CD8+ cells. Maximum levels of macrophages were seen at 4 months of age. These data argue for a major role of the proinflammatory cytokines TNF-alpha, IL-1beta, IL-6, IL- 12, IFN-gamma and cytolysin in initiation and perpetuation of autoimmune sialoadenitis in MRL/lpr mice, probably in conjunction with an insufficiency of the anti-inflammatory cytokines TGF-beta and IL-10.
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Dahiya R, Perinchery G, Deng G, Lee C. Multiple sites of loss of heterozygosity on chromosome 8 in human breast cancer has differential correlation with clinical parameters. Int J Oncol 1998; 12:811-6. [PMID: 9499440 DOI: 10.3892/ijo.12.4.811] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Recent studies have shown that chromosome 8p21-22 is the main site of frequent loss of heterozygosity (LOH) in breast cancers. However, the detailed molecular analysis of chromosome 8 so far in breast cancer has been variable. Most of the literature pertaining to LOH in breast cancer is mainly on short arm of chromosome 8. In the present study, we have examined LOH on both short and long arm of chromosome 8 using fifteen different polymorphic DNA markers in microdissected samples of normal breast epithelium and carcinoma from the same patients. For this purpose, DNA was extracted from the microdissected normal and tumor cells of 66 breast cancers, amplified by PCR and analyzed for LOH on chromosome 8 using fifteen different polymorphic DNA markers (D8S264, D8S298, D8S535, D8S255, D8S1098, D8S589, D8S567, D8S591, D8S285, D8S1102, D8S1763, D8S260, D8S530, D8S1772, and D8S1844). Expression of estrogen receptor, progesterone receptors, and p53 antigens was determined by immunohistochemistry using specific monoclonal antibodies. The results of this study suggest that LOH on chromosome 8 was identified in 40 of 66 cases (61%) with at least one marker. Three distinct regions of loss detected were: i) at 8p12, at loci between D8S535 and D8S255; ii) at 8p11, on loci D8S567, D8S591, D8S285, and D8S1102; iii) at 8q11-12, on loci D8S1763, D8S260 and D8S530. We found 45% (30 out of 66 informative cases) of the tumors showed LOH at 8p12; 52% (34 out of 66 informative cases) had LOH at 8p11; and 39% (26 out of 66 informative cases) had LOH at 8q11-12. Deletion at 8q11-12 was significantly correlated with the grade of the breast cancer specimens. Moderate to poorly differentiated specimens had higher incidence of LOH at 8q11-12 as compared to well differentiated specimens. Deletion at 8p12 and 8p11 was significantly higher in clinical stages III and IV of breast cancer tissues as compared to stage I and II cases. Tissues with lymph node involvement showed higher incidence of LOH at 8p12 as compared to the tissues with no lymph node involvement. There was no correlation of LOH at these loci with either the age of the patients, tumor size, BrdU labeling index, expression of estrogen receptor, progesterone receptor, and p53 in breast cancer specimens. These experiments, for the first time, report multiple sites of LOH on chromosome 8 in human breast cancer, and these deletions have differential correlation with clinical parameters of breast cancer samples.
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Deng G, Lane C, Kornblau S, Goodacre A, Snell V, Andreeff M, Deisseroth AB. Ratio of bcl-xshort to bcl-xlong Is Different in Good- and Poor-Prognosis Subsets of Acute Myeloid Leukemia. Mol Med 1998. [DOI: 10.1007/bf03401913] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Deng G, Lane C, Kornblau S, Goodacre A, Snell V, Andreeff M, Deisseroth AB. Ratio of bcl-xshort to bcl-xlong is different in good- and poor-prognosis subsets of acute myeloid leukemia. Mol Med 1998; 4:158-64. [PMID: 9562974 PMCID: PMC2230351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Acute myeloid leukemia (AML) is a heterogeneous collection of leukemic disorders ranging from chemotherapy-sensitive subsets [inversion 16 and t(8;21)], which often can be cured with cytosine arabinoside alone, to the most resistant subsets, which can survive even supralethal levels of combination alkylator chemotherapy (cytogenetic subsets monosomy 5 and monosomy 7). MATERIALS AND METHODS To analyze the expression of BCL-2 family genes, which are expressed in these subsets of AML, we used PCR sequence amplification reactions that are dependent on oligonucleotide primers representing the BH1 and BH2 homology domains to generate the unique regions between BH1 and BH2. These primers are conserved among all members of the BCL-2 gene family and are separated by a 150 nucleotide region sequence between the BH1 and BH2 domains. The PCR products unique to each BCL-2 family member were cloned directionally into sequencing vectors. The identity of the insert of each clone was determined by slotblots of the DNA amplified from individual colonies and by hybridization with radioactive probes specific to the bcl-2, bcl-x, or bax genes. RESULTS We found that bcl-2 is the predominant member expressed in AML samples with a poor prognosis (-5, -7), whereas the transcripts of bcl-x are higher than those of bcl-2 in the AML samples with a good prognosis [inv16, t(8;21)]. No significant difference in bax expression was detected between AML subsets of good and bad prognosis. The ratio of bcl-xlong, which inhibits apoptosis, to bcl-xshort, which promotes apoptosis, was determined by amplification with a pair of primers specific to bcl-x followed by separation of the PCR product on agarose gels. Bcl-xlong and bcl-xshort appeared as bands of different molecular mass on a molecular weight gel and were visualized by ethidium bromide staining or Southern blot analysis with a bcl-x-specific probe. CONCLUSIONS We found that the ratio of bcl-x long to bcl-x short was higher in the AML patients with a poor prognosis. These experiments showed that the levels of BCL-2 family members in the leukemia cells of good- and poor-prognosis subsets are different. In addition, novel members of the BCL-2 family were isolated from the cells of AML patients of either prognosis.
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Zhao Z, Deng G, Lui Q, Laursen RA. Cloning and sequencing of cDNA encoding the LS-12 antifreeze protein in the longhorn sculpin, Myoxocephalus octodecimspinosis. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1382:177-80. [PMID: 9540788 DOI: 10.1016/s0167-4838(97)00197-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
cDNA coding for an antifreeze protein (LS-12) in the longhorn sculpin, Myoxocephalus octodecimspinosis, was prepared from liver mRNA using reverse transcriptase-polymerase chain reaction coupled with 3' and 5' RACE procedures. This cDNA contains 609 base pairs, including a 384-bp open reading frame which codes for a 128-residue LS-12 precursor protein. The predicted amino acid sequence of the mature LS-12 corresponds exactly to the amino acid sequence obtained from Edman degradation [G. Deng, D.W. Andrews, R.A. Laursen, FEBS Lett., 402, 1997, pp. 17-20]. The 20 residues preceding mature LS-12 are predicted to be a signal sequence, which is presumably cleaved off before the mature, 108-residue protein is secreted into the circulatory system. This is the first report of a cDNA sequence from M. octodecimspinosis.
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Dahiya R, Deng G, Selph C, Carroll P, Presti J. A novel p53 mutation hotspot at codon 132 (AAG-->AGG) in human renal cancer. BIOCHEMISTRY AND MOLECULAR BIOLOGY INTERNATIONAL 1998; 44:407-15. [PMID: 9530523 DOI: 10.1080/15216549800201422] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Mutations of p53 tumor suppressor gene are the most common genetic alterations in a variety of human carcinomas. The sites of p53 mutations, however, vary in different cancers. The present study was designed to characterize p53 mutations in 40 primary human renal cancer specimens using hot-start-PCR-single-strand conformation polymorphism (SSCP) analysis, sequencing of PCR product and immunohistochemistry. DNA extracted from microdissected paraffin-embedded sections was amplified by hot-start-PCR using oligonucleotide primers specific for exons 4-9 of p53. The mutations were analyzed by PCR-SSCP technique and the generated fragments were denatured and analyzed by 6% polyacrylamide gel electrophoresis. The samples showing a band shift were denatured and sequenced using the Sequenase Version 2.0 DNA Sequencing Kit (US Biochemical, Cleveland, Ohio). Genomic DNA from control samples containing wild-type p53 alleles was sequenced in parallel for confirming mutations in samples that were positive for p53 in the PCR-SSCP analysis. The results of these experiments demonstrate that: (1) there were mutations in p53 exon 5 and 8 in 35% (14 out of 40 samples) of human renal cancer tissues as revealed by PCR-SSCP analysis; (2) DNA sequencing of samples showing frame-shift have hot spot of p53 mutation on exon 8 at codon 244 (GGC-->TGC) and exon 5 at codon 132 [AAG (Lys)-->AGG (Arg)]. This mutation in p53 exon 5 at codon 132 is novel and has not yet been reported; (3) immunohistochemical staining of p53 in renal cancer tissue using mouse anti-human p53 monoclonal antibody, clone PAb 1801, correlated with the p53 mutation assessed by PCR-SSCP. No correlation was found between p53 mutations and tumor stage and grade of renal cancer.
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90
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Su JH, Deng G, Cotman CW. Transneuronal degeneration in the spread of Alzheimer's disease pathology: immunohistochemical evidence for the transmission of tau hyperphosphorylation. Neurobiol Dis 1998; 4:365-75. [PMID: 9440125 DOI: 10.1006/nbdi.1997.0164] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Neurofibrillary tangles and dystrophic neurites appear to develop in a highly characteristic spatial and temporal sequence in AD. In order to examine the nature of the cellular progression we have studied the trisynaptic entorhinal, dentate gyrus, CA3/4 circuit, using an antibody to hyperphosphorylated tau which is a biochemical marker for tangle formation. In early AD cases, we found numerous ATB-stained boutons in the outer molecular layer of the dentate gyrus, the termination field of neurons from the entorhinal cortex. These AT8-stained boutons co-labeled with synaptophysin, indicating that they represent synaptic boutons in an early state of degeneration. Since the labeled boutons were apposed to or clustered around dendrites or soma that lacked or had less intense staining for AT8 or PHF-1, it appeared that presynaptic events preceded postsynaptic neurofibrillary tangle formation. Furthermore, as a function of disease progression, the pattern of degeneration moved through the circuit. In this progression tau, which is normally localized to axons, becomes redistributed into dendrites and hyperphosphorylated. These observations support the hypothesis that the presynaptic terminal changes may promote the formation of initial neurofibrillary pathology in the postsynaptic neurons via anterograde transneuronal mechanisms and that this initiates a breakdown of routing and sorting mechanisms for the cytoskeletal protein tau.
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91
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Su JH, Deng G, Cotman CW. Neuronal DNA damage precedes tangle formation and is associated with up-regulation of nitrotyrosine in Alzheimer's disease brain. Brain Res 1997; 774:193-9. [PMID: 9452208 DOI: 10.1016/s0006-8993(97)81703-9] [Citation(s) in RCA: 133] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The relationship of neuronal DNA damage to tangle-bearing neurons and nitrotyrosine (NT) expression, a neurochemical marker of oxidative damage mediated by peroxynitrite, was examined in visual cortex of AD patients. Many terminal deoxynucleotidyl transferase (TdT)-positive neurons were detected and the majority (93%) of these TdT-labeled neurons lacked evidence of tangle formation. NT expression was elevated in AD cases and most TdT-labeled nuclei also showed strong NT immunoreactivity. These data suggest the hypothesis that the neurons with DNA damage in the absence of tangle formation may degenerate by tangle-independent mechanisms and that oxidative damage may contribute to such mechanisms in AD.
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92
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Janout V, Lanier M, Deng G, Regen SL. Evidence for highly cooperative binding between molecular umbrella-spermine conjugates and DNA. Bioconjug Chem 1997; 8:891-5. [PMID: 9404663 DOI: 10.1021/bc970142r] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Double- and tetrawalled molecular umbrella-spermine conjugates (I and II) have been synthesized, and their binding to calf thymus DNA (CT-DNA), poly[d(AT)], and poly[d(GC)] compared with that of a single-walled analogue (III). At moderate salt concentrations (8 mM NaCl), I and II show significantly greater affinity toward each DNA, relative to III; at high salt concentrations (150 mM NaCl), strong binding of I and II (but not III) was maintained toward poly[d(GC)]. Examination of the influence of I-III on the melting behavior of poly[d(AT)] has provided strong evidence that the binding of I and II reflects highly cooperative interactions among DNA-bound conjugates and that the DNA duplex serves as a nucleation site for umbrella aggregation. The implications of these findings for the rational design of novel drug conjugates that operate at the nuclear level, and also novel transfection agents, are briefly discussed.
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93
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Dahiya R, Lee C, McCarville J, Hu W, Kaur G, Deng G. High frequency of genetic instability of microsatellites in human prostatic adenocarcinoma. Int J Cancer 1997; 72:762-7. [PMID: 9311591 DOI: 10.1002/(sici)1097-0215(19970904)72:5<762::aid-ijc10>3.0.co;2-b] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In order to investigate the genomic instability associated with prostate cancer, 36 microsatellite marker loci on chromosomes 1p, 3p, 5q, 8p, 8q, 9p, 11q and 13q were analyzed using microdissected samples from prostate cancer and adjoining microscopically normal tissues from the same slide. DNA was extracted from the normal and tumor cells of 40 microdissected prostate-cancer samples, amplified by PCR, and analyzed for microsatellite instability (MSI) using 36 different polymorphic DNA markers. In the present study, we have utilized a highly refined technique of PCR product separation on a sequencing gel, developed in our laboratory, which clearly shows high-quality results for the microsatellite instability in prostate cancer. The results of this study suggest that 45% (18 out of 40) showed genomic instability at a minimum of 1 locus; 4 cases each showed MSI at one and 2 loci, 4 cases had MSI at 3 loci, 3 cases showed MSI at 5 loci, while one case each showed MSI at 7, 8 and 15 loci. There was no significant correlation between the MSI and stage or grade of the tumors. This extensive study on genomic instability in prostate cancer found the occurrence of MSI to be very high, which suggests a role of MSI in the pathophysiology of prostate cancer.
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MESH Headings
- Adenocarcinoma/genetics
- Chromosomes, Human, Pair 1
- Chromosomes, Human, Pair 11
- Chromosomes, Human, Pair 13
- Chromosomes, Human, Pair 3
- Chromosomes, Human, Pair 5
- Chromosomes, Human, Pair 8
- Chromosomes, Human, Pair 9
- Genetic Markers
- Humans
- Male
- Microsatellite Repeats
- Mutation
- Polymerase Chain Reaction
- Prostatic Neoplasms/genetics
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94
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Cao LC, Boevé ER, de Bruijn WC, Kok DJ, de Water R, Deng G, Schröder FH. Glycosaminoglycans and semisynthetic sulfated polysaccharides: an overview of their potential application in treatment of patients with urolithiasis. Urology 1997; 50:173-83. [PMID: 9255284 DOI: 10.1016/s0090-4295(97)00227-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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95
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Dahiya R, McCarville J, Lee C, Hu W, Kaur G, Carroll P, Deng G. Deletion of chromosome 11p15, p12, q22, q23-24 loci in human prostate cancer. Int J Cancer 1997; 72:283-8. [PMID: 9219834 DOI: 10.1002/(sici)1097-0215(19970717)72:2<283::aid-ijc14>3.0.co;2-h] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Loss of heterozygosity (LOH) on chromosome 11 is frequently altered in various epithelial cancers. The present study was designed to investigate LOH on chromosome 11 in microdissected samples of normal prostatic epithelium and invasive carcinoma from the same patients. For this purpose, DNA was extracted from the microdissected normal and tumor cells of 38 prostate cancers, amplified by polymerase chain reaction PCR and analyzed for LOH on chromosome 11 using 9 different polymorphic DNA markers (D11S1307, D11S989, D11S1313, D11S898, D11S940, D11S1818, D11S924, D11S1336 and D11S912). LOH on chromosome 11 was identified in 30 of 38 cases (78%) with at least one marker. Four distinct regions of loss detected were: 1) at 11p15, at loci between D11S1307 and D11S989; 2) at 11p12, on locus D11S131 (11p12); 3) at 11q22, on loci D11S898, D11S940 and D11S1818; and 4) at 11q23-24, on loci between D11S1336 and D11S912. We found 25% of the tumors with LOH at 11p15; 39% had LOH at 11p12; 66% had LOH at 11q22; and 47% had LOH at 11q23-24. These deletions at 11p15, 11p12, 11q22 and 11q23-24 loci were not related to the stage or grade of the tumor.
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96
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Abstract
Identification of loss of heterozygosity on specific genetic loci is crucial for understanding the pathogenesis of prostate cancer at the molecular level. This is especially important because the deleted regions may contain putative tumor suppressor genes. Chromosome 3p loss appears to be frequently associated with various epithelial cancers. To our knowledge, there is no report on loss of heterozygosity (LOH) of chromosome 3 in human prostate cancer. The present study was designed to investigate the LOH on chromosome 3p in microdissected samples of delineated regions of normal and invasive carcinoma areas of prostatic epithelium from the same tumor sections. For this purpose, DNA was extracted from microdissected normal and tumor cells of 38 prostate cancers, amplified by PCR and analyzed for LOH on chromosome 3p using 6 different polymorphic DNA markers (D3S1560, THRB, D3S647, D3S1298, D3S1228 and D3S1296). Our results suggest that LOH was identified in 34 of 38 cases (89%) with at least one marker. Twelve of 30 informative cases showed LOH at D3S1560; 18 of 22 informative cases showed loss at THRB; 20 of 38 informative cases showed deletion at D3S647; 16 of 38 informative cases showed loss at D3S1298; 12 of 34 informative cases showed LOH at D3S1228; and 6 of 34 informative cases showed LOH at D3S1296 regions. Our results suggest that the LOH is on the 3p24-26 and 3p22-12 regions of the short arm of chromosome 3, indicating 2 discrete areas of deletion on chromosome 3p. The deletion at 3p24-26 and 3p22-12 was not related to the stage or grade of the tumor.
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97
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Deng G, Andrews DW, Laursen RA. Amino acid sequence of a new type of antifreeze protein, from the longhorn sculpin Myoxocephalus octodecimspinosis. FEBS Lett 1997; 402:17-20. [PMID: 9013849 DOI: 10.1016/s0014-5793(96)01466-4] [Citation(s) in RCA: 104] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A new type of fish antifreeze protein, designated here type IV, has been isolated from the longhorn sculpin, Myoxocephalus octodecimspinosis. Sequence analysis of the protein (LS-12) reveals that it contains 108 amino acids, is blocked at the N-terminus by a pyroglutamyl group and has a high (17%) content of glutamine; it is thus completely unrelated to the earlier described types I, II and III fish antifreeze proteins. Circular dichroism spectra and conformational analysis based on the sequence data indicate that LS-12 has a high helix content and probably folds as a four-helix bundle. LS-12 shows sequence similarity to certain plasma apolipoproteins known to have helix bundle structures, suggesting the possibility that LS-12 may have arisen by recruitment and mutation of a plasma apolipoprotein.
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98
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Su JH, Deng G, Cotman CW. Bax protein expression is increased in Alzheimer's brain: correlations with DNA damage, Bcl-2 expression, and brain pathology. J Neuropathol Exp Neurol 1997; 56:86-93. [PMID: 8990132 DOI: 10.1097/00005072-199701000-00009] [Citation(s) in RCA: 159] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
We have shown that many neurons in Alzheimer's disease (AD) exhibit terminal deoxynucleotidyl transferase (TdT) labeling for DNA strand breaks, and upregulation of Bcl-2 is associated with neurons exhibiting nuclear DNA fragmentation, while downregulation of Bcl-2 is associated with tangle-bearing neurons in AD brains. Consequently, we examined the expression of bcl-associated X (Bax) protein in AD brain. Immunoreactivity for Bax was seen in neurons and microglia of the hippocampal formation, and was elevated in the majority of AD cases as compared to control cases. Interestingly, 3 transitional cases, which had mild degeneration changes, exhibited relatively high levels of Bax immunoreactivity. Most Bax-positive neurons showed either TdT-labeled nuclei or Bcl-2 immunoreactivity. Although Bax immunoreactivity was detected within most early tangle-bearing neurons, many Bax-positive neurons did not colocalize with later-stage tangle-bearing neurons. In regions containing relatively few tangles in mild AD brains, many TdT-labeled neurons were immunolabeled with Bax antibody and most of them lacked evidence of neurofibrillary changes. These findings suggest that Bax may contribute to neuronal cell death in AD. Furthermore, DNA damage and the upregulation of Bax appear to precede tangle formation or may represent an alternative pathway of cell death in AD.
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99
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Cao LC, Deng G, Boevé ER, Romijn JC, de Bruijn WC, Verkoelen CF, Schröder FH. Does urinary oxalate interfere with the inhibitory role of glycosaminoglycans and semisynthetic sulfated polysaccharides in calcium oxalate crystallization? Eur Urol 1997; 31:485-92. [PMID: 9187912 DOI: 10.1159/000474511] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVES Previously it was shown that the polysaccharide G872 in vitro strongly inhibits calcium oxalate monohydrate crystallization processes. However, when rats on a stone-inducing diet of ethylene glycol plus vitamin D3 are given this polysaccharide, no changes in the urine capacity for crystallization inhibition were found. We investigated here how the inhibitory action of polysaccharides changes under high oxalate conditions, as they exist in the stone inducing diet. METHODS Calcium oxalate monohydrate (COM) crystals were incubated in a series of 0.05 M PBS buffers containing polysaccharides with increasing oxalate concentrations (0-0.4 mmol/l). The coated crystals were collected, washed and resuspended in an artificial urine. We then measured the zeta potential of the crystals, using a Coulter DELSA 440, and the initial rates for crystal growth and agglomeration, using the Coulter Multisizer II. RESULTS Addition of oxalate to the medium shifts the negative zeta potential distribution of COM crystals coated by polysaccharides in positive direction. Particle size analysis demonstrated that the initial rates of COM crystal growth and agglomeration responding to oxalate concentration changes (0.1-->0.4 mmol/l) in the presence of G872 (0.2 mg/l) are approximately 2.5 times faster than that in the absence of G872. CONCLUSIONS Oxalate interferes with the binding of polysaccharides to crystals. This can be envisioned to occur through changes in the crystal surface properties or by induction of functional and secondary structural changes of urinary macromolecular inhibitors such as GAGs, resulting in a decrease of their inhibitory activity against COM crystallization. Thus, in urine, a high oxalate may increase the rate of crystallization both by increasing the supersaturation and by decreasing the inhibitory potential of the urine.
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100
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Deng G, Lu Y, Zlotnikov G, Thor AD, Smith HS. Loss of heterozygosity in normal tissue adjacent to breast carcinomas. Science 1996; 274:2057-9. [PMID: 8953032 DOI: 10.1126/science.274.5295.2057] [Citation(s) in RCA: 385] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Loss of heterozygosity (LOH) was detected in morphologically normal lobules adjacent to breast cancers. The most frequent aberration was at chromosome 3p22-25; of ten cases with this LOH in the carcinoma, six displayed the same LOH in adjacent normal lobules. This suggests that in a subset of sporadic breast cancers, a tumor suppresser gene at 3p22-25 may be important in initiation or early progression of tumorigenesis. Among sixteen breast cancers with LOH at 17p13.1 and five breast cancers with LOH at 11p15.5, one case each displayed the same LOH in adjacent normal lobules. Thus the molecular heterogeneity that characterizes invasive breast cancers may occur at the earliest detectable stages of progression.
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MESH Headings
- Alleles
- Breast/chemistry
- Breast/pathology
- Breast Neoplasms/chemistry
- Breast Neoplasms/genetics
- Breast Neoplasms/pathology
- Carcinoma, Ductal, Breast/chemistry
- Carcinoma, Ductal, Breast/genetics
- Carcinoma, Ductal, Breast/pathology
- Chromosomes, Human, Pair 11
- Chromosomes, Human, Pair 13
- Chromosomes, Human, Pair 17
- Chromosomes, Human, Pair 3
- DNA/genetics
- DNA, Neoplasm/genetics
- Female
- Gene Deletion
- Heterozygote
- Humans
- Polymerase Chain Reaction
- Receptor, ErbB-2/analysis
- Tumor Suppressor Protein p53/analysis
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