151
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Pannu H, Tran-Fadulu V, Papke CL, Scherer S, Liu Y, Presley C, Guo D, Estrera AL, Safi HJ, Brasier AR, Vick GW, Marian A, Raman C, Buja LM, Milewicz DM. MYH11 mutations result in a distinct vascular pathology driven by insulin-like growth factor1 and angiotensin II. Hum Mol Genet 2007. [DOI: 10.1093/hmg/ddm313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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152
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Fan L, Zhang W, Guo D, Tan ZR, Xu P, Li Q, Liu YZ, Zhang L, He TY, Hu DL, Wang D, Zhou HH. The Effect of Herbal Medicine Baicalin on Pharmacokinetics of Rosuvastatin, Substrate of Organic Anion-transporting Polypeptide 1B1. Clin Pharmacol Ther 2007; 83:471-6. [PMID: 17851565 DOI: 10.1038/sj.clpt.6100318] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [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: 01/04/2023]
Abstract
The aim of this study was to explore potential herb-drug interaction between baicalin and rosuvastatin, a typical substrate for organic anion-transporting polypeptide 1B1 (OATP1B1) related to different OATP1B1 haplotype groups. Eighteen unrelated healthy volunteers who were CYP2C9*1/*1 with different OATP1B1 haplotypes (six OATP1B1*1b/*1b, six OATP1B1*1b/*15, and six OATP1B1*15/*15) were selected to participate in this study. Rosuvastatin (20 mg orally) pharmacokinetics after coadministration of placebo and 50-mg baicalin tablets (three times daily orally for 14 days) were measured for up to 72 h by liquid chromatography-mass spectrometry in a two-phase randomized crossover study. After baicalin treatment, the area under the plasma concentration-time curve (AUC)(0-72) and AUC(0-infinity) of rosuvastatin decreased by 47.0+/-11.0% (P=0.001) and 41.9+/-7.19% (P=0.001) in OATP1B1*1b/*1b, 21.0+/-20.6% (P=0.035) and 23.9+/-8.66% (P=0.004) in OATP1B1*1b/*15, and 9.20+/-11.6% (P=0.077) and 1.76+/-4.89% (P=0.36) in OATP1B1*15/*15, respectively. Moreover, decreases of both AUC(0-72) and AUC(0-infinity) of rosuvastatin among different haplotype groups were significantly different (P=0.002 and <0.001). Baicalin reduces plasma concentrations of rosuvastatin in an OATP1B1 haplotype-dependent manner.
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Affiliation(s)
- L Fan
- Pharmacogenetics Research Institute, Central South University, Changsha, Hunan, People's Republic of China
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153
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Abstract
1. B- and M-mode echocardiography was used to compare cardiac function in broilers with spontaneous ascites syndrome with that of normal chickens. 2. Thirty ascitic chickens and 15 normal chickens aged three, 4, 5, and 6 weeks from the same flock (180 birds in total) were examined. They were restrained gently in a natural standing position, and echocardiographs were obtained from a 7.0-MHz linear transducer placed on the left pectoral apterium. Indices of cardiac structure and functioning were calculated from the echocardiographs, and some were normalised to body weight. Heart rate was also measured. 3. All cardiac structural indices in both ascitic and normal chickens increased with age. Compared with normal chickens, right ventricular diameter at the end of systole in ascitic chickens was greater at 4, 5 and 6 weeks of age. Ventricular septal thickness at the end of both systole and diastole was greater in ascitic chickens at 5 and 6 weeks. Left ventricular free wall thickness at the end of diastole was less in ascitic chickens at 3 weeks. However, all the structural indices decreased with age after normalisation with body weight. 4. The heart rate of ascitic chickens was lower at 4, 5 and 6 weeks. Normalised left ventricular fractional shortening was lower in ascitic chickens at 4, 5 and 6 weeks, as was normalised right ventricular fractional shortening. Incrassation of the ventricular septum (Delta T), which changed little in normal chickens, was less at 4, 5 and 6 weeks in ascitic chickens. Left ventricular fractional shortening, right ventricular fractional shortening and Delta T were all negatively correlated with ascites heart index at all ages. 5. Taken together the results suggest heart failure of both ventricle, but that right ventricular dysfunction is more extensive than left ventricular dysfunction. We suggest that secondary pulmonary hypertension would result in these ascitic chickens due to volume overload.
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Affiliation(s)
- G Deng
- Veterinary Medical College of Huazhong Agricultural University, Wuhan 430070, P.R. China.
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154
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Zang S, Ji C, Qu X, Dong X, Ma D, Ye J, Ma R, Dai J, Guo D. A study on Notch signaling in human breast cancer. Neoplasma 2007; 54:304-10. [PMID: 17822320] [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: 05/17/2023]
Abstract
Breast cancer is one of the leading causes of cancer death in women. The Notch family of proteins plays crucial roles in determining cell fates such as proliferation, differentiation and apoptosis. A role for Notch signaling in human breast cancer has been suggested by the development of adenocarcinomas in the murine mammary gland. However, it is not clear currently whether Notch signaling is frequently expressed and activated in breast cancers. Here we show that Notch signaling is overexpressed and highly activated in breast cancers. More significantly, the attenuation of Notch signaling by gamma-secretase inhibitor can inhibit the proliferation of breast cancer cells by both causing cell cycle arrest and apoptosis. Thus, targeting Notch signaling may be of therapeutic value in breast cancers.
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MESH Headings
- Adaptor Proteins, Signal Transducing
- Amyloid Precursor Protein Secretases/antagonists & inhibitors
- Amyloid Precursor Protein Secretases/metabolism
- Apoptosis/physiology
- Basic Helix-Loop-Helix Transcription Factors/genetics
- Basic Helix-Loop-Helix Transcription Factors/metabolism
- Breast/metabolism
- Breast/pathology
- Breast Neoplasms/genetics
- Breast Neoplasms/metabolism
- Breast Neoplasms/pathology
- Calcium-Binding Proteins/genetics
- Calcium-Binding Proteins/metabolism
- Cell Cycle/physiology
- Cell Line, Tumor
- Cell Proliferation
- Homeodomain Proteins/genetics
- Homeodomain Proteins/metabolism
- Humans
- Intercellular Signaling Peptides and Proteins/genetics
- Intercellular Signaling Peptides and Proteins/metabolism
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Protease Inhibitors/pharmacology
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Neoplasm/genetics
- RNA, Neoplasm/metabolism
- Receptor, Notch1/genetics
- Receptor, Notch1/metabolism
- Receptor, Notch3
- Receptor, Notch4
- Receptors, Notch/genetics
- Receptors, Notch/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Serrate-Jagged Proteins
- Signal Transduction
- Transcription Factor HES-1
- Up-Regulation
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Affiliation(s)
- S Zang
- Department of Hematology, Qilu Hospital, Shandong University, Jinan, P. R. China
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155
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Zhang Y, Liu M, Qu L, Xiang W, Guo D, Yuan X, Ge M, Zhang C. Sequence and phylogenetic analysis of the S-class genome segments of a duck orthoreovirus. Acta Virol 2007; 51:239-247. [PMID: 18197731] [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: 05/25/2023]
Abstract
In spite of common properties duck orthoreoviruses (DRVs) are antigenically different from other avian orthoreoviruses (ARVs). We analyzed the S-class genome segments of the DRV S12 and compared them with S-class genome segments of other orthoreoviruses compared to those of ARV S1133. The full-length S-class sigmaA, sigmaB, sigmaNS, and sigmaC genes were determined and compared with other ARVs to study the degree of genetic divergence and evolution of DRVs. The alignment of the DRV S12 sigmaA, sigmaB, sigmaNS, and sigmaC genes with DRV 89026 showed 90.0%, 93.6%, 88.0%, and 93.1% nucleotide identity and 97.1%, 94.3%, 95.8%, and 93.7% amino acid identity, respectively. The alignment of the DRV S12 sigmaA, sigmaB, sigmaNS, and sigmaC genes with other ARVs revealed 76.0-77.1%, 52.5-55.1%, 78.4-79.6%, and 2.7-9.9% nucleotide identity and 89.5-91.2%, 61.4-62.0%, 91.6-92.7% and 22.6-26.7% amino acid identity, respectively. Phylogenetic analyses demonstrated that DRVs were quite different from other ARVs and provided the evidence for the diversity among avian orthoreoviruses.
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Affiliation(s)
- Y Zhang
- Avian Infectious Disease Division, National Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute of Chinese Academy of Agricultural Sciences, Harbin, PR China.
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156
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Homandberg GA, Guo D, Ray LM, Ding L. Mixtures of glucosamine and chondroitin sulfate reverse fibronectin fragment mediated damage to cartilage more effectively than either agent alone. Osteoarthritis Cartilage 2006; 14:793-806. [PMID: 16581272 DOI: 10.1016/j.joca.2006.02.003] [Citation(s) in RCA: 16] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Accepted: 02/02/2006] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To test the effectiveness of glucosamine (GluNH(2))-HCl, chondroitin sulfate (CS) and mixtures in protecting cartilage exposed to fibronectin fragments (Fn-fs), an exposure known to enhance catabolic cytokines and matrix metalloproteinases (MMPs). METHODS Pharmacologic formulations of GluNH(2) (FCHG49) and CS (TRH122) (Nutramax Laboratories, Inc.) were added at 1, 10 or 100 microg/ml singly or in mixtures to bovine cartilage cultures in serum or serum-free conditions with or without Fn-f. Proteoglycan (PG) release into media and remaining cartilage PG content were measured by dye binding analysis and effects on PG synthesis by assays of 35-sulfate incorporation. Effects on MMP-3 and -13 expression were measured by Western blotting of conditioned media. RESULTS In serum-free conditions, the agents singly or as mixtures did not block Fn-f mediated matrix degradation. In serum, single agents were weakly effective at 100 microg/ml, while the mixture of each agent at 0.1 microg/ml decreased PG loss by about 50% by day 7 and at 1 microg/ml restored nearly 50% of the PG after 7 days in Fn-f pretreated cartilage. However, both agents singly and as mixtures at 0.1-100 microg/ml decreased MMP release. In serum, the single agents at 1-10 microg/ml weakly reversed Fn-f mediated PG synthesis suppression, while the mixtures were 100% effective at 1 microg/ml. CONCLUSIONS GluNH(2) and CS act synergistically in reversing damage and promoting repair at concentrations found in plasma after oral ingestion of these agents. Reversal of PG synthesis suppression correlates more with these activities than suppression of MMP-3 or -13 expression.
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Affiliation(s)
- G A Homandberg
- Department of Biochemistry and Molecular Biology, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58202, USA.
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157
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Lu Q, Li XH, Guo D, Xu CG, Zhang Q. Localization of pms3, a gene for photoperiod-sensitive genic male sterility, to a 28.4-kb DNA fragment. Mol Genet Genomics 2005; 273:507-11. [PMID: 15912317 DOI: 10.1007/s00438-005-1155-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2004] [Accepted: 04/20/2005] [Indexed: 10/25/2022]
Abstract
Photoperiod-sensitive genic male-sterile (PSGMS) rice, in which pollen fertility is regulated by day-length, originally arose as a natural mutant in the rice cultivar Nongken 58 (Oryza sativa ssp. japonica). Previous studies identified pms3 on chromosome 12 as the locus of the original PSGMS mutation. In this study we have assigned the pms3 locus to a 28.4-kb DNA fragment by genetic and physical mapping. A cross between Nongken 58S (PSGMS line) and DH80 was used to produce an F2 population of about 7000 plants, from which 892 highly sterile individuals were obtained for recombination analysis. By analyzing recombination events in the sterile individuals using a total of 157 RFLP probes from a BAC contig covering the pms3 region, the pms3 locus was localized to a sub-region of less than 1.7 cM. Further analysis of recombination events using 49 additional probes isolated from this sub-region identified markers flanking the pms3 region on each side; these markers are only 28.4-kb apart. Sequence analysis of this fragment predicted the presence of five ORFs, found high homology with two ESTs in public databases, and detected three SNPs between the mutant and the wild-type parents, which may be helpful for identifying a candidate gene for pms3.
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Affiliation(s)
- Q Lu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research Wuhan, Huazhong Agricultural University, Wuhan 430070, China
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158
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Yang W, Kalajzic I, Lu Y, Guo D, Harris MA, Gluhak-Heinrich J, Bonewald LF, Feng JQ, Rowe DW, Harris SE. In vitro and in vivo study on osteocyte-specific mechanical signaling pathways. J Musculoskelet Neuronal Interact 2004; 4:386-7. [PMID: 15758272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Affiliation(s)
- W Yang
- Department of Periodontics, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA
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159
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Kalajzic I, Braut A, Guo D, Jiang X, Kronenberg MS, Mina M, Harris MA, Harris SE, Rowe DW. Dentin matrix protein 1 expression during osteoblastic differentiation, generation of an osteocyte GFP-transgene. Bone 2004; 35:74-82. [PMID: 15207743 DOI: 10.1016/j.bone.2004.03.006] [Citation(s) in RCA: 161] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2004] [Revised: 03/01/2004] [Accepted: 03/08/2004] [Indexed: 11/26/2022]
Abstract
Our previous studies have demonstrated that promoter-green fluorescent protein (GFP) transgenes can be used to identify and isolate populations of cells at the preosteoblastic stage (pOBCol3.6GFP) and at the mature osteoblastic stage (pOBCol2.3GFP) in living primary bone cell cultures. This strategy forms the basis for appreciating the cellular heterogeneity of lineage and relating gene function to cell differentiation. A weakness of this approach was the lack of a selective marker for late osteoblasts and mature osteocytes in the mineralized matrix. In this study, we have examined the expression of DMP-1 mRNA in murine marrow stromal and calvarial osteoblast cultures, and in bone, and calvaria in vivo. Furthermore, we have generated transgenic mice utilizing a mouse DMP1 cis-regulatory system to drive GFP as a marker for living osteocytes. Transgene expression was directed to mineralized tissues and showed a high correlation with the expression of the endogenous gene. Osteocyte-restricted expression of GFP was observed in histological sections of femur and calvaria and in primary cell cultures. Generation of this transgenic model will facilitate studies of gene expression and biological functions in these terminally differentiated bone cells.
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Affiliation(s)
- I Kalajzic
- Department of Genetics and Developmental Biology, University of Connecticut Health Center, Farmington 06030, USA.
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160
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Zhang H, Zhu Z, Liu L, Guo D, Jiang T, Wang L, Qiao Z. Upregulation of Fas and FasL expression in testosterone-induced apoptosis of macrophages. ACTA ACUST UNITED AC 2004; 25:779-84. [PMID: 14735224 DOI: 10.1358/mf.2003.25.10.793325] [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: 10/25/2022]
Abstract
To the best of the authors' knowledge, there have been few reports on the effect of testosterone on the apoptosis of macrophages. In this report, we studied the effect of testosterone on the apoptosis of bone marrow-derived macrophages (BMMs) and the function of the Fas/Fas ligand (FasL) system in the process. Results showed that testosterone treatment in vitro at the physiological concentration of 10 nM did not induce the apoptosis of BMMs. However, BMMs underwent apoptosis when treated at higher concentrations of testosterone (100, 200 and 400 nM). Testosterone-induced apoptosis was associated with the enhanced expression of Fas, FasL, and caspase-8. These data suggest that the Fas/FasL system may play an important role in the testosterone-induced apoptosis of macrophages.
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Affiliation(s)
- H Zhang
- Division of Parasitology, School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, PR China
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161
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Karlsson L, Quinlan D, Guo D, Brown C, Selinger S, Klassen J, Russell JA. Mobilized blood cells vs bone marrow harvest: experience compared in 171 donors with particular reference to pain and fatigue. Bone Marrow Transplant 2004; 33:709-13. [PMID: 14755321 DOI: 10.1038/sj.bmt.1704418] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [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: 11/09/2022]
Abstract
This prospective study compared the donor experience of blood cell (BC) mobilization and leukapheresis (n=116) with that of bone marrow (BM) harvest (n=55). Internal jugular catheters were inserted electively in 89% of BC donors. Most (80%) BM donors had a harvest with general anesthesia; 20% had epidural or spinal anesthesia. Pain and fatigue were frequent with both procedures and were compared in responses to questionnaires. A total of 85% of BM donors reported moderate or severe pain compared with 68% of BC donors (P=0.02). The median duration of pain was 14 days for BM donors compared with 3 days after BC mobilization (P<0.0001). More BM donors had pain for more than 7 days (75% vs 0%, P<0.0001). Severe fatigue was experienced by more BM donors (49 vs 16%, P<0.0001). Fatigue lasted significantly longer in BM donors (median 11 vs 4 days, P<0.0001) and more BM donors were fatigued for more than 1 week (69 vs 0%, P<0.0001). A total of 11 donors had both BM and BC collection; seven preferred the latter. Simply considered with respect to pain and fatigue, BC donation appears better tolerated by donors. However, there are other sequelae of both influencing the acceptability for individual donors.
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Affiliation(s)
- L Karlsson
- Alberta Bone Marrow Transplant Program and Department of Medicine, Tom Baker Cancer Centre, Calgary, Alberta, Canada
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162
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Thomasson M, Hedman H, Guo D, Ljungberg B, Henriksson R. LRIG1 and epidermal growth factor receptor in renal cell carcinoma: a quantitative RT--PCR and immunohistochemical analysis. Br J Cancer 2003; 89:1285-9. [PMID: 14520461 PMCID: PMC2394322 DOI: 10.1038/sj.bjc.6601208] [Citation(s) in RCA: 55] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
In all, 31 renal cell carcinomas (RCCs) were examined for expression of the potential tumour suppressor LRIG1 (formerly Lig-1) and the epidermal growth factor receptor (EGFR). Eight matched samples of uninvolved kidney cortex were also evaluated. Gene expression was examined by quantitative real-time RT–PCR. In the eight matched sample pairs (uninvolved kidney cortex and tumour), protein expression was examined by immunohistochemistry. Conventional (clear cell) tumours showed an expected upregulation of EGFR. LRIG1 expression was generally downregulated in conventional and papillary RCC but not in chromophobic RCC. The ratio between EGFR and LRIG1 was more than 2.5-fold higher in the eight tumours compared with matched uninvolved kidney cortex and was at least two-fold higher than the mean normal ratio in 21 of 31 samples analysed. The observed downregulation of LRIG1 and increased EGFR/LRIG1 ratios are consistent with LRIG1 being a suppressor of oncogenesis in RCC by counteracting the tumour-promoting properties of EGFR. Further studies are justified to elucidate the explicit role of LRIG1 in the oncogenesis of RCC.
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Affiliation(s)
- M Thomasson
- Department of Radiation Sciences, Oncology, Umeå University Hospital, Umeå, Sweden
| | - H Hedman
- Department of Radiation Sciences, Oncology, Umeå University Hospital, Umeå, Sweden
| | - D Guo
- Department of Radiation Sciences, Oncology, Umeå University Hospital, Umeå, Sweden
| | - B Ljungberg
- Department of Surgical and Perioperative Sciences, Urology, Umeå University Hospital, Umeå, Sweden
| | - R Henriksson
- Department of Radiation Sciences, Oncology, Umeå University Hospital, Umeå, Sweden
- AstraZeneca, Medical Department, Mölndal, Sweden
- Department of Radiation Sciences, Oncology, Umeå University, SE-901 87 Umeå, Sweden. E-mail:
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163
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Perianayagam MC, Balakrishnan VS, Guo D, Pereira BJG, Jaber BL. Quantification of Bax and Bcl2 in polymorphonuclear leukocytes from haemodialysis patients: relation to hydrogen peroxide. Eur J Clin Invest 2003; 33:905-11. [PMID: 14511363 DOI: 10.1046/j.1365-2362.2003.01225.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Bax and Bcl2 are two apoptosis-related molecules that play an important role in determining cell fate following oxidative injury. In the present study, we explored the relation of hydrogen peroxide (H2O2) generation by polymorphonuclear cells (PMNs) to the cytosolic expression of Bax and Bcl2 proteins and apoptosis in haemodialysis (HD) patients. METHODS Cytosolic generation of H2O2 by PMNs from control subjects and HD patients was measured by flow cytometry using the dichlorofluorescin diacetate assay. Bax and Bcl2 expression was detected by flow cytometry using FITC-conjugated antibodies. Apoptosis was quantified by flow cytometry using propidium iodide nuclear staining. To examine the effect of H2O2 on Bcl2 and Bax expression, PMNs from control subjects were briefly exposed to H2O2 (0.1-100 microM) for 10 min and then washed and cultured for 6 h, with or without catalase, a H2O2 detoxifying molecule. Bcl2 and Bax expression was determined by Western blot analysis. RESULTS Basal H2O2 generation by resting PMNs was significantly higher in HD patients compared with control subjects (211 +/- 115 vs. 23 +/- 5 MFI; P=0.002). However, PMNs from HD patients did not undergo accelerated programmed cell death compared with control subjects (58 +/- 7% vs. 46 +/- 5; P=0.14). Polymorphonuclear cells cytosolic Bcl2 was undetected in control subjects but detected in 25% of HD patients, and Bax was more frequently detected in PMNs from HD patients (75% vs. 67%; P=0.04). In the HD patients with detectable cytosolic Bax and Bcl2 proteins, the Bax to Bcl2 ratio inversely correlated with H2O2 levels (P<0.0001). Finally, brief exposure of PMNs to 0.1-100 microM of H2O2 resulted in a marked increase in Bcl2 expression (P=0.001), which was prevented by catalase (P=0.05). There was no apparent effect on Bax expression. CONCLUSIONS This study demonstrates that in HD patients, high-resting cytosolic H2O2 production by PMNs is not associated with accelerated in vitro apoptosis, and that the Bax/Bcl2 system may counter-balance the deleterious effects of reactive oxygen species in human PMNs.
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Affiliation(s)
- M C Perianayagam
- Department of Medicine, Tufts-New England Medical Center, Boston, MA 02111, USA
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164
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Guo D, Jaber BL, Lee S, Perianayagam MC, King AJ, Pereira BJG, Balakrishnan VS. Impact of iron dextran on polymorphonuclear cell function among hemodialysis patients. Clin Nephrol 2002; 58:134-42. [PMID: 12227686 DOI: 10.5414/cnp58134] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Polymorphonuclear cell (PMN) dysfunction and the increased use of parenteral iron may be important contributory factors to bacterial infections among patients with end-stage renal disease (ESRD) on maintenance hemodialysis (HD). We compared the in vitro impact of a commonly used parenteral iron preparation, iron dextran, on PMN function and viability between a group of HD patients with normal iron indices and healthy subjects. METHODS Eleven patients with ESRD on HD and 10 healthy subjects were studied. PMN harvested from heparinized blood were incubated with iron dextran (0 - 20 mM) in culture medium (RPMI) for 24 hours at 37 degrees C with 5% CO2 following which function and viability were assessed by flow cytometry using appropriate fluorescent labels. RESULTS Unstimulated, S. aureus and N-formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated hydrogen peroxide (H2O2) production was significantly higher in PMN unexposed to iron dextran from HD patients compared to those from healthy subjects. Iron dextran had no impact on unstimulated PMN H2O2 production in either group. In the healthy group, the only significant change occurred with 4-beta-phorbol 12-beta-myristate 13-alpha-acetate (PMA) stimulation, where cells exposed to 0.2 and 2.0 mM iron dextran produced less H2O2 relative to PMN unexposed to iron dextran (p < 0.05). In the HD group, all concentrations of iron dextran significantly attenuated H2O2 production stimulated by S. aureus, fMLP and PMA compared to PMN unexposed to iron dextran. Although PMN phagocytosis decreased with exposure to increasing concentration of iron dextran in both healthy subjects and HD patients, these changes did not achieve statistical significance. No significant changes in PMN viability or apoptosis were seen in either group after exposure to iron dextran. CONCLUSIONS These results indicate that iron dextran, a standard parenteral iron preparation, attenuates PMN function in HD patients with normal iron indices at clinically relevant concentrations. Further studies are required to evaluate and compare the impact of newer preparations of parenteral iron, such as iron sucrose and ferric gluconate, on PMN function.
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Affiliation(s)
- D Guo
- Department of Medicine, New England Medical Center Hospitals, Boston, MA 02111, USA
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165
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Zhang X, Wang L, Zhang H, Guo D, Zhao J, Qiao Z, Qiao J. The effects of cigarette smoke extract on the endothelial production of soluble intercellular adhesion molecule-1 are mediated through macrophages, possibly by inducing TNF-alpha release. Methods Find Exp Clin Pharmacol 2002; 24:261-5. [PMID: 12168501 DOI: 10.1358/mf.2002.24.5.802302] [Citation(s) in RCA: 10] [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: 10/25/2022]
Abstract
Cigarette smoke (CS) is a major risk factor for many human diseases, although the underlying mechanisms are not clearly understood. This study was undertaken to investigate the effect of a water-soluble CS extract (CSE) on soluble intercellular adhesion molecule-1 (sICAM-1) production by human umbilical vein endothelial cells (HUVEC) mediated through ANA-1 macrophages. First, macrophages were incubated with or without CSE, and the supernatants collected at different time points were used to measure the levels of tumor necrosis factor-alpha (TNF-alpha) and sICAM-1 by enzyme-linked immunosorbent assay (ELISA); and second, HUVEC were cultured with CSE, a vehicle, or ANA-1 supernatants (collected at different time points) and the sICAM-1 levels in the supernatants were measured by ELISA at 24 h. The results showed that: i) CSE showed no effect on the production of sICAM-1 by HUVEC; ii) sICAM-1, in unstimulated or CSE-stimulated ANA-1 supernatants collected at different time points, was under the detectable level; iii) CSE-stimulated ANA-1 supernatants collected at 3 or 6 h showed no effect on sICAM-1 production in HUVEC, while those collected at 12 and 24 h significantly increased sICAM-1 production (p < 0.02 and p < 0.005, respectively); iv) no significant difference in TNF-alpha levels was detected between unstimulated and CSE-stimulated macrophage supernatants collected at 3 and 6 h, however, higher levels of TNF-alpha were found in CSE-stimulated supernatants collected at 12 and 24 h (p < 0.05 and p < 0.002, respectively); and v) a significant correlation (r = 0.9693, p < 0.001) was found between the levels of TNF-alpha in CSE-stimulated ANA-1 supernatants and those of related sICAM-1 production in HUVEC. These findings indicate that CSE indirectly increases the production of sICAM-1 in HUVEC by activating macrophages, which possibly induces the release of TNF-alpha from them, which in turn enhances the production of sICAM-1 from HUVEC.
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Affiliation(s)
- X Zhang
- Laboratory of Molecular Biology, 1st Hospital, Taiyuan, P.R. China
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166
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Feng J, Zhang J, Tan X, Lu Y, Guo D, Harris S. Identification of Cis-DNA Regions Controlling Bmp4 Expression during Tooth Morphogenesis in vivo. J Dent Res 2002. [DOI: 10.1177/154405910208100103] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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167
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Abstract
Epithelial-mesenchymal interactions are required for tooth formation. Bone morphogenetic protein 4 (Bmp4) is a crucial signaling molecule during this process. For better understanding of the role of the Bmp4 gene during tooth development, we studied the mechanisms that control its temporal and spatial expression during development. Using a transgenic approach, we determined that the domains which controlled Bmp4 expression in epithelium-derived ameloblasts were located in the region between 0.26 kb and 1.1 kb of the murine Bmp4 promoter. In contrast, the domains controlling Bmp4 expression in mesenchyme-derived odontoblasts and pulp cells existed in other regions of the Bmp4 gene. We have also demonstrated that the domains controlling Bmp4 expression in primordial tooth cells differ from those controlling Bmp4 expression in mature tooth tissues. The determination of unique domains by controlling the expression of the Bmp4 gene suggests that different transcriptional factors regulate the Bmp4 level at different stages during tooth morphogenesis.
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Affiliation(s)
- J Q Feng
- School of Dentistry, Dept. of Oral Biology, University of Missouri-Kansas City, 64108, USA.
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168
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Chen B, Fu W, Guo D, Wang Y. [Endovascular treatment for peripheral arterial stenosis with endoluminal stent]. Zhonghua Wai Ke Za Zhi 2001; 39:911-4. [PMID: 16201168] [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: 05/04/2023]
Abstract
OBJECTIVE To initially evaluate the effect and security of endovascular treatment for arterial stenosis with endoluminal stent. METHODS Thirty-four cases of arterial stenosis were treated with endoluminal stent from March 1999 to May 2001. The stenosis involved descending aorta (1 case), iliac artery (2), femoral artery (2), carotid artery (1), subclavian artery (2) and renal artery (1). Thiry-three cases had arteriosclerosis and one Takayasu's arteritis. Twenty-six cases were percutaneously punctured and eight cases were punctured directly. RESULTS All the 34 cases had the stents successfully implanted. However, one case of descending aorta stenosis died on the operation day due to rupture of the descending aorta. Dissection was performed in thirteen cases after balloon dilation and hematoma was seen at the puncturing point in eleven cases. TIA (transient ischemia attack) and cerebral infarction did not occur in the case of carotid arterial stenosis. For those with stenosis in lower extremities, ABI (ankle-brachial index) increased from 0.45 to 0.72 postoperatively. The brachial pressure of two cases of subclavian arterial stenosis returned to normal postoperatively. The blood pressure of case of renal arterial stenosis reduced from 180/120 mm Hg to 140/90 mm Hg. All the cases were followed up for one month to 26 months. Thrombosis of the arteries treated occurred in two cases of iliac arterial stenosis four and six months postoperatively. CONCLUSIONS The effect of endovascular treatment for arterial stenosis with endoluminal stent is satisfactory. Endovascular therapy is especially suitable for iliac arterial and limited stenosis of the subclavian artery. However, it should be cautiously used in the stenosis of the carotid artery.
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Affiliation(s)
- B Chen
- Department of Vascular Surgery, Zhongshan Hospital, Fudan University Medical College, Shanghai 200032, China
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169
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Guo D, Chen F, Wheeler J, Winder J, Selman S, Peterson M, Dixon RA. Improvement of in-rumen digestibility of alfalfa forage by genetic manipulation of lignin O-methyltransferases. Transgenic Res 2001; 10:457-64. [PMID: 11708655 DOI: 10.1023/a:1012278106147] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.0] [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
Lignin inhibits forage digestibility by ruminant animals, and lignin levels and the proportion of dimethylated syringyl (S) lignin monomers increase with progressive maturity in stems of forage crops. We generated transgenic alfalfa (Medicago sativa L.) with reduced lignin content and altered lignin composition. Down-regulation of caffeic acid 3-O-methyltransferase (COMT) reduces lignin content, accompanied by near total loss of S lignin, whereas down-regulation of caffeoyl coenzyme A 3-O-methyltransferase (CCoAOMT) reduces lignin content without reduction in S lignin. These changes are not accompanied by altered ratios of cell wall polysaccharides. Analysis of rumen digestibility of alfalfa forage in fistulated steers revealed improved digestibility of forage from COMT down-regulated plants, but a greater improvement in digestibility following down-regulation of CCoAOMT. The results indicate that both lignin content and composition affect digestibility of alfalfa forage, and reveal a new strategy for forage quality improvement by genetic manipulation of CCoAOMT expression.
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Affiliation(s)
- D Guo
- Plant Biology Division, Samuel Roberts Noble Foundation, Ardmore, OK 73401, USA
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170
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Zhou J, Higashi K, Ueda Y, Kodama Y, Guo D, Jisaki F, Sakurai A, Takegami T, Katsuda S, Yamamoto I. Expression of multidrug resistance protein and messenger RNA correlate with (99m)Tc-MIBI imaging in patients with lung cancer. J Nucl Med 2001; 42:1476-83. [PMID: 11585860] [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
UNLABELLED In vitro studies have shown that (99m)Tc-sestamibi (MIBI) is a transport substrate for the P-glycoprotein (Pgp) pump and the multidrug resistance-associated protein (MRP) pump. However, whether MRP and lung resistance protein (LRP) affect tumor accumulation and efflux of (99m)Tc-MIBI in lung cancer is not known. In this study, we explored whether Pgp and the other pumps, MRP and LRP, affect tumor accumulation and efflux of (99m)Tc-MIBI in lung cancer. METHODS Thirty-four lung cancer patients who underwent surgery were examined. Before surgery, (99m)Tc-MIBI SPECT was performed 15 min and 180 min after injection, and early uptake, delayed uptake (L/Nd), and washout rate (L/Nwr) of (99m)Tc-MIBI were obtained. Pgp, MRP, and LRP expression were investigated by immunohistochemistry. The messenger RNA (mRNA) level of Pgp, MRP, and LRP was determined by real-time reverse-transcription polymerase chain reaction. The lung cancer (99m)Tc-MIBI images were correlated with protein and mRNA expression. RESULTS The mean L/Nd of the Pgp (-) group was significantly higher than that of the Pgp (++) group (P = 0.0324). The Pgp (++) group had a higher L/Nwr than did the Pgp (-) group (P = 0.0269). The mean L/Nd of the Pgp mRNA low-expression group was significantly higher than that of the Pgp mRNA high-expression group (P = 0.0127). The Pgp mRNA high-expression group had a higher L/Nwr than did the Pgp mRNA low-expression group (P = 0.0825). No appreciable correlation was found between the lung cancer (99m)Tc-MIBI images and the expression of MRP or LRP on the level of protein or mRNA. CONCLUSION These data suggest that an increased level of Pgp expression correlates with a low accumulation on delayed scans and a high L/Nwr of (99m)Tc-MIBI in lung cancer. Neither MRP nor LRP expression on the level of either protein or mRNA correlated significantly with tumor accumulation or efflux of (99m)Tc-MIBI in lung cancer.
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Affiliation(s)
- J Zhou
- Department of Radiology, Medical Research Institute, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Kahoku-gun, Ishikawa, 920-0293, Japan
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171
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Langs DA, Blessing RH, Guo D. Map self-validation: improved criteria to resolve the SIR or SAS phase ambiguity. Acta Crystallogr D Biol Crystallogr 2001; 57:1351-3. [PMID: 11526342 DOI: 10.1107/s0907444901011696] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2001] [Accepted: 07/11/2001] [Indexed: 11/10/2022]
Abstract
A procedure was recently described that used the correlation coefficient (CC) agreement between the observed /F(h)/ and their associated unbiased 'omit map' extrapolated values /X(h)/ from an initial trial map as the basis for resolving the SIR or SAS phase ambiguity. It is noted here that a significant improvement in selectivity can be obtained if this agreement is expressed in terms of the complex-valued F(h) and X(h). A new scheme is outlined to exploit the weighted average of the two SIR or SAS phase choices. This procedure requires six FFTs per phase compared with three for the older method that randomly selected either of the two permitted phase choices from the Argand diagram as starting values. Trial calculations are encouraging for applications as low as 4 A resolution.
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Affiliation(s)
- D A Langs
- Hauptman-Woodward Medical Research Institute Inc., 73 High Street, Buffalo, NY 14203, USA.
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172
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Zhang X, Guo D, Gao J. [Experimental comparison of the adipocytal injuries harvested by three surgical methods]. Zhonghua Zheng Xing Wai Ke Za Zhi 2001; 17:290-1. [PMID: 11767707] [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: 02/23/2023]
Abstract
OBJECTIVE To evaluate the degree of the injuries on the fat cells harvested by cutting, syringe aspiration and pipe suction techniques. METHODS Fat tissue was removed from lower abdomen by cutting, syringe aspiration and pipe suction. The excised adipose tissue was cut into 3 mm diameter fat particles, whereas the adipose tissue from syringe aspiration group was taken by the syringe suction technique with No. 22 needle and in the pipe suction group the adipose tissue from the suction tube with 8 mm in diameter. Each sample was fixed in 10% buffered formalin and stained with hematoxylin technique and wilder's silver technique. The fat cells were evaluated under microscope. RESULTS The percentage of the injured fat cells was (8.6 +/- 1.8)% in cutting technique, (15.7 +/- 2.4)% in syringe aspiration and (76.4 +/- 8.7)% in pipe suction respectively. They had significant differences between each other. CONCLUSIONS Among the three methods, the degree of the injuries on the fat cells was mostly serious in the way of pipe suction technique while minimal in the way by cutting.
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Affiliation(s)
- X Zhang
- Department of Burn and Plastic Surgery, 174 Hospital of PLA, Xiamen 361003, China
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173
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Lu W, Guo D, Miao J, Liu C, Hu S, Liu W, Jiao H. [An initial study on DSA features of pulmonary hypoperfusion second to cancerous invasion of central pulmonary artery in lung cancer]. Zhongguo Fei Ai Za Zhi 2001; 4:293-295. [PMID: 21050582 DOI: 10.3779/j.issn.1009-3419.2001.04.13] [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: 05/30/2023]
Abstract
BACKGROUND To study digital subtraction angiography ( DSA) features of pulmonary hypoperfusion in lung cancer with cancerous invasion of central pulmonary artery ( CICPA) . METHODS Twenty-six cases of lung cancer combined with CICPA underwent pulmonary DSA. The DSA features of pulmonary hypoperfusion, including pulmonary vessel signs and lung parenchyma signs, were observed, and the time-density curve( TDC) of both abnormal sides and the coordinate normal sides was drawn and analyzed. RESULTS There were 38 lobar arteries showing cancerous invasion in 26 cases and 34 ( 89. 5%) lobes presenting pulmonary hypoperfusion. There was a good correlation between pulmonary hypoperfusion and the degree of central pulmonary artery ( CPA) stenosis ( P < 0. 05) . DSA pulmonary vessel signs included abrupt cut-off ( 11. 8%, 4/ 34) or less branches ( 88. 2%, 30/ 34) of pulmonary arteries, and disappearance ( 41. 2%, 14/ 34) or decrease ( 58. 8%, 20/ 34) of terminal pulmonary arteries. DSA lung parenchyma signs were pulmonary capillary perfusion disappearing ( 14. 7%, 5/ 34) or weakening ( 85. 3%, 29/ 34) . CONCLUSIONS Pulmonary lobes supplied by central pulmonary arteries invaded by lung cancers usually present pulmonary hypoperfusion. Pulmonary hypoperfusion is closely correlative with the degree of CPA stenosis. Pulmonary vessel signs and lung parenchyma signs are very important phenomena of pulmonary hypoperfusion.
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Affiliation(s)
- W Lu
- Department of Radiology , West China Hospital, Sichuan University ( Former The First UniversityHospital of West China University of Medical Sciences) , Chengdu, Sichuan 610041, P. R . China
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174
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Dixon RA, Chen F, Guo D, Parvathi K. The biosynthesis of monolignols: a "metabolic grid", or independent pathways to guaiacyl and syringyl units? Phytochemistry 2001; 57:1069-84. [PMID: 11430980 DOI: 10.1016/s0031-9422(01)00092-9] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Lignin is a complex polymer formed by the oxidative polymerization of hydroxycinnamyl alcohol derivatives termed monolignols. The major monolignols in dicotyledonous angiosperm lignin are monomethylated guaiacyl (G) units derived from coniferyl alcohol, and dimethylated syringyl (S) units derived from sinapyl alcohol. The biochemical pathways leading to the formation of monolignols feature successive hydroxylation and O-methylation of the aromatic ring and conversion of the side chain carboxyl to an alcohol function. The current view of the monolignol biosynthetic pathway envisages a metabolic grid leading to G and S units, through which the successive hydroxylation and O-methylation reactions may occur at different levels of side chain oxidation. The present article assesses biochemical and genetic evidence for and against such a model, including recent data on the methylation reactions of monolignol biosynthesis in alfalfa. We draw attention to portions of the currently accepted monolignol pathway that may require revision, and suggest an alternative model in which metabolic channeling allows for independent pathways to G and S lignin.
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Affiliation(s)
- R A Dixon
- Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA.
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175
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Fu H, Koike K, Zheng Q, Mitsunaga K, Jia Z, Nikaido T, Lin W, Guo D, Zhang L. Fargosides A-E, triterpenoid saponins from Holboellia fargesii. Chem Pharm Bull (Tokyo) 2001; 49:999-1002. [PMID: 11515592 DOI: 10.1248/cpb.49.999] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Five new triterpenoid saponins, fargosides A, B, C, D, and E, were isolated from the roots of Holboellia fargesii. The structures of fargosides A-E were elucidated on the basis of chemical and physicochemical evidence and found to be 3beta,20alpha-dihydroxy-29-norolean-12-en-28-oic acid 3-O-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (1), 3beta,20alpha,24-trihydroxy-29-norolean-12-en-28-oic acid 23-O-beta-D-fucopyranosyl-(1-->2)-[alpha-L-arabinopyranosyl-(1-->3)]-beta-D-glucopyranoside (2), 3beta,23-dihydroxy-30-norolean-2,20(29)-dien-28-oic acid 3-O-alpha-L-arabinopyranosyl-(1-->2)-[beta-D-glucopyranosyluronic acid-(1-->3)]-alpha-L-arabinopyranoside (3), 3beta,23-dihydroxy-30-norolean-12,20(29)-dien-28-oic acid 3-O-methyl beta-D-glucopyranosyluronate-(1-->3)-alpha-L-arabinopyranoside (4), and 3beta,23-dihydroxy-olean-12-en-28-oic acid 3-O-methyl beta-D-glucopyranosyluronate-(1-->3)-alpha-L-arabinopyranoside (5), respectively.
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Affiliation(s)
- H Fu
- Department of Pharmacognosy, School of Pharmaceutical Sciences, Toho University, Funabashi, Chiba, Japan
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176
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Wu X, Guo D, Yuan F, Wang Z. Accessibility of DNA polymerases to repair synthesis during nucleotide excision repair in yeast cell-free extracts. Nucleic Acids Res 2001; 29:3123-30. [PMID: 11452038 PMCID: PMC55800 DOI: 10.1093/nar/29.14.3123] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [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: 11/13/2022] Open
Abstract
Nucleotide excision repair (NER) removes a variety of DNA lesions. Using a yeast cell-free repair system, we have analyzed the repair synthesis step of NER. NER was proficient in yeast mutant cell-free extracts lacking DNA polymerases (Pol) beta, zeta or eta. Base excision repair was also proficient without Polbeta. Repair synthesis of NER was not affected by thermal inactivation of the temperature-sensitive mutant Polalpha (pol1-17), but was reduced after thermal inactivation of the temperature-sensitive mutant Poldelta (pol3-1) or Polvarepsilon (pol2-18). Residual repair synthesis was observed in pol3-1 and pol2-18 mutant extracts, suggesting a repair deficiency rather than a complete repair defect. Deficient NER in pol3-1 and pol2-18 mutant extracts was specifically complemented by purified yeast Poldelta and Polvarepsilon, respectively. Deleting the polymerase catalytic domain of Polvarepsilon (pol2-16) also led to a deficient repair synthesis during NER, which was complemented by purified yeast Polvarepsilon, but not by purified yeast Poleta. These results suggest that efficient repair synthesis of yeast NER requires both Poldelta and Polvarepsilon in vitro, and that the low fidelity Poleta is not accessible to repair synthesis during NER.
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Affiliation(s)
- X Wu
- 306 Health Sciences Research Building, Graduate Center for Toxicology, University of Kentucky, Lexington, KY 40536, USA
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177
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Guo D, Hasham S, Kuang SQ, Vaughan CJ, Boerwinkle E, Chen H, Abuelo D, Dietz HC, Basson CT, Shete SS, Milewicz DM. Familial thoracic aortic aneurysms and dissections: genetic heterogeneity with a major locus mapping to 5q13-14. Circulation 2001; 103:2461-8. [PMID: 11369686 DOI: 10.1161/01.cir.103.20.2461] [Citation(s) in RCA: 157] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Aneurysms and dissections affecting the ascending aorta are associated primarily with degeneration of the aortic media, called medial necrosis. Families identified with dominant inheritance of thoracic aortic aneurysms and dissections (TAA/dissections) indicate that single gene mutations can cause medial necrosis in the absence of an associated syndrome. METHODS AND RESULTS Fifteen families were identified with multiple members with TAAs/dissections. DNA from affected members from 2 of the families was used for a genome-wide search for the location of the defective gene by use of random polymorphic markers. The data were analyzed by the affected-pedigree-member method of linkage analysis. This analysis revealed 3 chromosomal loci with multiple markers demonstrating evidence of linkage to the phenotype. Linkage analysis using further markers in these regions and DNA from 15 families confirmed linkage of some of the families to 5q13-14. Genetic heterogeneity for the condition was confirmed by a heterogeneity test. Data from 9 families with the highest conditional probability of being linked to 5q were used to calculate the pairwise and multipoint logarithm of the odds (LOD) scores, with a maximum LOD of 4.74, with no recombination being obtained for the marker D5S2029. In 6 families, the phenotype was not linked to the 5q locus. CONCLUSIONS A major locus for familial TAAs and dissections maps to 5q13-14, with the majority (9 of 15) of the families identified demonstrating evidence of linkage to this locus. The condition is genetically heterogeneous, with 6 families not demonstrating evidence of linkage to any loci previously associated with aneurysm formation.
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Affiliation(s)
- D Guo
- Department of Internal Medicine, University of Texas-Houston Medical School, Houston, TX 77030, USA
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178
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Guo D, Wu X, Rajpal DK, Taylor JS, Wang Z. Translesion synthesis by yeast DNA polymerase zeta from templates containing lesions of ultraviolet radiation and acetylaminofluorene. Nucleic Acids Res 2001; 29:2875-83. [PMID: 11433034 PMCID: PMC55783 DOI: 10.1093/nar/29.13.2875] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In the yeast Saccharomyces cerevisiae, DNA polymerase zeta (Polzeta) is required in a major lesion bypass pathway. To help understand the role of Polzeta in lesion bypass, we have performed in vitro biochemical analyses of this polymerase in response to several DNA lesions. Purified yeast Polzeta performed limited translesion synthesis opposite a template TT (6-4) photoproduct, incorporating A or T with similar efficiencies (and less frequently G) opposite the 3' T, and predominantly A opposite the 5' T. Purified yeast Polzeta predominantly incorporated a G opposite an acetylaminofluorene (AAF)-adducted guanine. The lesion, however, significantly inhibited subsequent extension. Furthermore, yeast Polzeta catalyzed extension DNA synthesis from primers annealed opposite the AAF-guanine and the 3' T of the TT (6-4) photoproduct with varying efficiencies. Extension synthesis was more efficient when A or C was opposite the AAF-guanine, and when G was opposite the 3' T of the TT (6-4) photoproduct. In contrast, the 3' T of a cis-syn TT dimer completely blocked purified yeast Polzeta, whereas the 5' T was readily bypassed. These results support the following dual-function model of Polzeta. First, Polzeta catalyzes nucleotide incorporation opposite AAF-guanine and TT (6-4) photoproduct with a limited efficiency. Secondly, more efficient bypass of these lesions may require nucleotide incorporation by other DNA polymerases followed by extension DNA synthesis by Polzeta.
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Affiliation(s)
- D Guo
- Graduate Center for Toxicology, 306 Health Sciences Research Building, University of Kentucky, Lexington, KY 40536, USA
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179
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Zhao J, Wang Z, Guo D, Yu C, Xie W, Li G. [CT appearance and its diagnosis value in liver cancer after transcatheter oily chemoembolization combining with high intensity focused ultrasound therapy]. Zhonghua Gan Zang Bing Za Zhi 2001; 9 Suppl:61-3. [PMID: 11509143] [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: 02/21/2023]
Abstract
OBJECTIVE To study the CT appearances of liver cancer after transcatheter oily chemoembolization (TOCE) combining with high intensity focused ultrasound (HIFU) therapy. METHODS Fifty cases of clinically-proved liver cancer were included into this study. For each case, CT scanning before and after TOCE, HIFU treatment was performed. The volumes of the masses were measured. The appearances of the oily deposition and the density, shape, border of the lesions were observed. RESULTS The lesions became smaller in 38 cases (38/50, 76%) after the treatment. The differences were detected statistically in the ratio of the tumor shrinkage between the single TOCE therapy and the combined treatment (P<0.05). The ratio of the tumor shrinkage was closely correlative with the quantity of the oily deposition, but not with the diameter of the tumor before treatment. The lowered densities were showed in 30 cases (30/50, 60%) and the borders became regular and clear in 16 cases after HIFU therapy. CONCLUSIONS TOCE combining with HIFU therapy in the patients with liver cancer can make the tumor smaller. CT is of great value in the evaluation of efficacy and prognosis.
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Affiliation(s)
- J Zhao
- Department of Radiology and Center for Tumor Therapy, Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China
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180
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Nilsson J, Vallbo C, Guo D, Golovleva I, Hallberg B, Henriksson R, Hedman H. Cloning, characterization, and expression of human LIG1. Biochem Biophys Res Commun 2001; 284:1155-61. [PMID: 11414704 DOI: 10.1006/bbrc.2001.5092] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.5] [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: 11/22/2022]
Abstract
Growth factor receptors are frequently amplified and over-expressed in various human cancers. Recently, a Drosophila cell surface protein, Kekkon-1, was found to participate in an epidermal growth factor (EGF) driven negative feedback loop. Kekkon-1 is induced by EGF, binds to the EGF-receptor, and inhibits receptor-mediated signaling. Here, we have searched for human genes with homologies to Kekkon-1 and identified human LIG1. The gene is the human homologue of mouse Lig-1 and is located on chromosome band 3p14, a region frequently deleted in various human cancers. It is predicted to encode a transmembrane cell-surface protein with extracellular leucine-rich repeats and immunoglobulin-like domains. LIG1 mRNA was detected in all tissues analyzed. The highest and lowest relative expression levels were found in brain and spleen, respectively, and differed by more than 200-fold. Taken together, our data are compatible with a role for LIG1 as a growth and tumor suppressor in human tissues.
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Affiliation(s)
- J Nilsson
- Department of Radiation Sciences, Umeå University, Umeå, SE-90187, Sweden
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181
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Craighead P, Herring C, Hillier C, Guo D, Budden J, Rans K. The use of the Australian Basic Treatment Equivalent (BTE) workload measure for linear accelerators in Canada. Clin Oncol (R Coll Radiol) 2001; 13:8-13. [PMID: 11292144 DOI: 10.1053/clon.2001.9208] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The Inter Society of Radiation Oncologists of North America (ISRON) workload standard for linear accelerators is the one most widely used; it regards the treatment of 250 or more patients per year as an acceptable limit. Nevertheless, there is concern that this standard does not represent the current workload of linear accelerators, given that the complexity of techniques and equipment has increased significantly since the ISRON model was developed in the late 1980s. Delaney et al. recently validated a workload indicator for Australian (AUS) centres, known as the basic treatment equivalent (BTE). They showed that this was a better predictor of workload and that there was less variation between centres using this model than there would have been by using fields/hour. This centre attempted to validate this model for use in a Canadian centre, by collecting treatment data on all linear accelerator-treated patients during February 1998. The linear accelerators at this centre delivered 2,295 fractions (6,928 fields) in 662 hours during February 1998. When 15 minutes was used as a denominator, the BTE model functioned as a better workload indicator than simple measures such as fields/hour. It also had better performance in reducing variability between machines. A BTE of 3,403 was calculated for these machines. The mean value for fields/hour, BTE/hour and BTE/fraction for this centre fell within the range of values quoted by AUS centres. The BTE/fraction value for this centre was relatively high compared with the AUS mean, indicating this centre's reliance on the use of a high number of complex techniques. We recommend that the model should be further refined for the Canadian context by developing BTE values with the use of local time and motion studies, including factors such as multileaf collimators and enhanced dynamic wedges.
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182
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Abstract
Mutations in FBN1 cause the autosomal dominant condition, Marfan syndrome. A single-base mutation that results in a skipping of exon 2 of FBN1 was found in a Marfan patient. By sequencing this proband's entire FBN1 gene and comparing the mutated DNA sequence with proband's unaffected family numbers, we confirmed this alteration was the causative mutation. The skipping of exon 2 creates a frameshift and premature termination codon, and forms a truncated fibrillin-1 composed only of 55 amino acids of N-terminus plus 45 nonsense amino acids. The mRNA transcription levels of the mutated FBN1 allele and the deposition of fibrillin-1 into extracellular matrix in fibroblast cells culture were assessed.
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Affiliation(s)
- D Guo
- Department of Internal Medicine, University of Texas-Houston Medical School, Houston, Texas 77030, USA
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183
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Stewart DA, Guo D, Luider J, Auer I, Klassen J, Morris D, Brown CB, Chaudhry A, Glück S, Russell JA. The CD3- 16+ 56+ NK cell count independently predicts autologous blood stem cell mobilization. Bone Marrow Transplant 2001; 27:1237-43. [PMID: 11548841 DOI: 10.1038/sj.bmt.1703070] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [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: 11/09/2022]
Abstract
Better predictive factors for autologous blood stem cell mobilization (BSCM) are needed. The purpose of this study was to determine if an independent association exists between lymphocyte or NK cell counts and BSCM. Data were analyzed on 141 consecutive patients aged 19-69 years (median 45) who received combined chemotherapy plus G-CSF for BSCM, and who had measurements of immune cells prior to BSCM. Of the 141 patients, 41% had breast cancer, 14% Hodgkin's disease, 34% non-Hodgkin's lymphoma, and 11% other diagnoses. BSCM involved dose-intensive cyclophosphamide, etoposide, cisplatin (DICEP) plus G-CSF 300 microg (<70 kg) or 480 microg (>70 kg) for 45% of patients, while the remaining 55% received other chemotherapy plus similar doses of G-CSF. Only a single apheresis was performed for 94% of patients. The following factors were analyzed for predictors of BSCM: age, gender, prior chemotherapy, prior radiotherapy, diagnosis, disease status, marrow involvement, mobilization regimen, Hb, WBC, platelet count, B cell, T cell, and NK cell counts. The peripheral blood CD34+ counts on the first day of apheresis (PBCD34) were 6-1783 x 10(6)/l (median 150). The PBCD34 count correlated strongly with the number of CD34+ cells collected/l blood apheresed and with the number of CD34+ cells collected/kg. By multivariate analysis using continuous variables, relapsed status (P = 0.0003), not using DICEP mobilization (P = 0.0001), female gender (P = 0.0057), low platelet count (P = 0.051), and low CD3- 16+ 56+ count (P = 0.0158) were associated with low PBCD34 counts. Using categorical variables, the only factors that independently predicted a PBCD34 count <150 x 10(6)/l were: >1 prior chemotherapy regimen (odds ratio = 5.12, P = 0.0003), not using DICEP mobilization (odds ratio = 4.94, P = 0.0001), and CD3- 16+ 56+ count <125 x 10(6)/l (odds ratio= 2.58, P = 0.0157). In conclusion, the CD3- 16+ 56+ count may be a useful additional predictor of BSCM and warrants further study.
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Affiliation(s)
- D A Stewart
- Department of Medicine, Tom Baker Cancer Centre, University of Calgary, Alberta, Canada
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184
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Vaughan CJ, Casey M, He J, Veugelers M, Henderson K, Guo D, Campagna R, Roman MJ, Milewicz DM, Devereux RB, Basson CT. Identification of a Chromosome 11q23.2-q24 Locus for Familial Aortic Aneurysm Disease, a Genetically Heterogeneous Disorder. Circulation 2001; 103:2469-75. [PMID: 11369687 DOI: 10.1161/01.cir.103.20.2469] [Citation(s) in RCA: 133] [Impact Index Per Article: 5.8] [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: 01/12/2023]
Abstract
Background
—Aortic aneurysms cause significant mortality, and >20% relate to hereditary disorders. Familial aortic aneurysm (FAA) has been described in such conditions as the Marfan and Ehlers-Danlos type IV syndromes, due to defects in the
fibrillin-1
and
type III procollagen
genes, respectively. Other gene defects that cause isolated aneurysms, however, have not thus far been described.
Methods and Results
—We studied 3 families affected by FAA. No family met the diagnostic criteria for either Marfan or Ehlers-Danlos syndrome. Echocardiography defined involvement of both the thoracic and abdominal aorta. In family ANA, candidate gene analysis excluded linkage to loci associated with aneurysm formation, including
fibrillin-1
,
fibrillin-2
, and
type III procollagen
, and chromosome 3p24.2-p25. Genome-wide linkage analysis identified a 2.3-cM FAA locus (
FAA1
) on chromosome 11q23.3-q24 with a maximum multipoint logarithm of the odds score of 4.4. In family ANB, FAA was linked to
fibrillin-1
. In family ANF, however, FAA was not linked to any locus previously associated with aneurysm formation, including
fibrillin-1
and
FAA1
.
Conclusions
—FAA disease is genetically heterogeneous. We have identified a novel FAA locus at chromosome 11q23.3-q24, a critical step toward elucidating 1 gene defect responsible for aortic dilatation. Future characterization of the
FAA1
gene will enhance our ability to achieve presymptomatic diagnosis of aortic aneurysms and will define molecular mechanisms to target therapeutics.
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Affiliation(s)
- C J Vaughan
- Division of Cardiology, Department of Medicine, Weill Medical College of Cornell University, The New York Presbyterian Hospital, New York, NY 10021, USA
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185
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Langs DA, Blessing RH, Guo D. Improvement of SAS triple invariant estimates for macromolecular direct-methods phasing. Acta Crystallogr A 2001; 57:240-3. [PMID: 11326108 DOI: 10.1107/s010876730001610x] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2000] [Accepted: 11/03/2000] [Indexed: 11/10/2022] Open
Abstract
Single-wavelength anomalous dispersion (SAS) data can in principle be phased by direct methods since a priori estimates of the three-phase structure invariants can be computed from these data. The mean phase error of the most reliable triple estimates for a small protein, however, is typically no better than 60 degrees, and does not bode well for applications to larger structures. A procedure is described that can substantially lower the error in these estimates and introduce a larger number of useful triple invariants into the phasing process. The mean phase error of the most reliable triples for a 2.5 A resolution data set from a Pt derivative of a 115-residue protein was reduced from 55 to 25 degrees by this method. It was also possible to identify a significant number of the poorest triple estimates, those with mean phase errors approaching 90 degrees, such that they could be reliably down-weighted or excluded from the phasing process.
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Affiliation(s)
- D A Langs
- Hauptman-Woodward Medical Research Institute, Inc., 73 High Street, Buffalo, NY 14203, USA.
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186
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Zhang X, Wang L, Zhang H, Guo D, Qiao Z, Qiao J. Estrogen inhibits lipopolysaccharide-induced tumor necrosis factor-alpha release from murine macrophages. Methods Find Exp Clin Pharmacol 2001; 23:169-73. [PMID: 11676224 DOI: 10.1358/mf.2001.23.4.634640] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
During their reproductive years, female have a lower risk for atherosclerosis as compared with age-matched males, although the mechanisms behind this are not clearly understood. Cytokines, including TNF-alpha play an important role in the pathogenesis of atherosclerosis. We therefore evaluated whether or not there was any difference between 17 beta-estradiol and testosterone in modulating TNF-alpha release from murine bone marrow-derived macrophages (BMM) in vitro. Cells were incubated with or without physiological concentrations (10(-10)-10(-8) M) of 17 beta-estradiol or testosterone for 48 h, followed by an additional 6 h in the absence or presence of lipopolysaccharide (LPS; 10 micrograms/ml). The amount of TNF-alpha released into the culture medium was determined with radioimmunoassay. We found that 17 beta-estradiol or testosterone alone did not affect TNF-alpha release from BMM as compared to untreated controls. Preincubation with 17 beta-estradiol significantly inhibited LPS-induced TNF-alpha release by 18.15% (p < 0.05). 25.28% (p < 0.05) and 40.83% (p < 0.01) for 10(-10), 10(-9) and 10(-8) M of 17 beta-estradiol, respectively, as compared to LPS alone. In contrast, testosterone tested for 3 concentrations did not significantly effect TNF-alpha release induced by LPS. The results indicate that 17 beta-estradiol, but not testosterone, inhibits TNF-alpha release from LPS-stimulated macrophages, which may be one of the mechanisms by which estrogen protects against atherosclerosis.
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Affiliation(s)
- X Zhang
- Laboratory of Molecular Biology, Shanxi Medical University, Taiyuan, P.R. China.
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187
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Guo D, Lu W, Miao J, Guan Y, Hou C, Hu S. [An initial imaging study on pulmonary artery hypertension secondary to cancerous invasion of central pulmonary artery in lung cancer]. Zhongguo Fei Ai Za Zhi 2001; 4:137-139. [PMID: 21044473 DOI: 10.3779/j.issn.1009-3419.2001.02.16] [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: 05/30/2023]
Abstract
BACKGROUND To investigate the incidence of pulmonary artery hypertension secondary to cancerous invasion of central pulmonary artery (CICPA) in lung cancer and the diagnostic value of CT on pulmonary artery hypertension. METHODS Twenty cases of lung cancer combined with CICPA underwent pulmonary artery pressure measurement through right heart catheterization and CT scanning. CT findings were blindly assessed and were compared with the results of pulmonary artery pressure measurement. RESULTS Three cases (3/20, 15%) showed mild pulmonary artery hypertension in arteries proximal to CICPA segments, in which CT findings were dilation of the main pulmonary artery and increase of the diameter ratio of the main pulmonary artery to the descending aorta at the same level. CT diagnostic accuracy for pulmonary artery hypertension was 90%(18/20). CONCLUSIONS Pulmonary artery hypertension occurs with low incidence in lung cancer with CICPA. CT is of great value in diagnosing pulmonary artery hypertension in lung cancer with CICPA.
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Affiliation(s)
- D Guo
- Department of Radiology, The First University Hospital, West China University of Medical Sciences, Chengdu, Sichuan 610041, P.R.China
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188
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Langs DA, Blessing RH, Guo D. Map self-validation: a useful discriminator of phase correctness at low resolution. Acta Crystallogr D Biol Crystallogr 2001; 57:574-8. [PMID: 11264587 DOI: 10.1107/s0907444901001123] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2000] [Accepted: 01/16/2001] [Indexed: 11/10/2022]
Abstract
A new map-validation procedure is based on the correlation-coefficient agreement between the observed structure-factor magnitudes and their extrapolated values from suitably modified electron-density maps from which they have been each in turn systematically excluded. The correlation coefficient tends to a maximum as the phase errors in a map are reduced. This principle was used to resolve the single-wavelength anomalous scattering (SAS) and single-derivative isomorphous replacement (SIR) phase ambiguity for a number of error-free trial structures. Applications employing real data sets tend to be more difficult owing to data incompleteness and errors affecting the construction of the Argand diagram.
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Affiliation(s)
- D A Langs
- Hauptman-Woodward Medical Research Institute Inc., 73 High Street, Buffalo, NY 14203, USA.
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189
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Shen XM, Wu SH, Yan CH, Zhao W, Ao LM, Zhang YW, He JM, Ying JM, Li RQ, Wu SM, Guo D. Delta-aminolevulinate dehydratase polymorphism and blood lead levels in Chinese children. Environ Res 2001; 85:185-190. [PMID: 11237505 DOI: 10.1006/enrs.2000.4230] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study investigated the relationship between the delta-aminolevulinate dehydratase (ALAD) isozymes and the blood lead levels of Chinese children. The purpose of this study was to determine the precise ALAD genotyping in Chinese children and identify the contribution of the ALAD genotype to the body lead burden. Blood samples were obtained from 109 boys and 120 girls. These children were 6-10 years old and from a single primary school. Both the school and their homes were within a community in which a large smelter was located. An environmental questionnaire was obtained for each subject, and blood lead levels and ALAD isozyme phenotype were analyzed in a double-blinded fashion. The blood lead levels of 229 children ranged from 4.5 to 26.4 microg/dl; the mean was 10.3 microg/dl and the standard deviation was 3.3 microg/dl. The gene distribution of the ALAD isozyme phenotypes in these environmentally exposed children was ALAD 1-1 (92%), ALAD 1-2, (8%), and ALAD 2-2 (0%). The mean blood level of the environmentally exposed children, who were homozygous for the ALAD1 allele, was 9.7 microg/dl; the mean for those who were heterozygous for the ALAD2 allele was 11.7 microg/dl. Using the t test, the means of the groups were different at the level of t=2.2058, P<0.05. Step-wise regression and multiple analyses of covariance were employed to control the confounders to measuring the independent contribution of the ALAD genotype on blood lead levels. After controlling the confounders, the contribution of the ALAD genotype to the blood lead level was greater and still statistically significant (F=7.3201, P<0.01). These results indicate that individuals carrying the ALAD2 allele are more likely to have sustained increases in blood lead levels when exposed to a lead-contaminated environment.
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Affiliation(s)
- X M Shen
- Research Center for Childhood Lead Poisoning Prevention, Xin-Hua Hospital, Shanghai Second Medical University, 1665 Kong Jiang Road, Shanghai, 200092, China
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190
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Oruetxebarria I, Guo D, Merits A, Mäkinen K, Saarma M, Valkonen JP. Identification of the genome-linked protein in virions of Potato virus A, with comparison to other members in genus Potyvirus. Virus Res 2001; 73:103-12. [PMID: 11172914 DOI: 10.1016/s0168-1702(00)00216-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Viruses of the genus Potyvirus, the largest genus of plant-infecting viruses, have a messenger-polarity ssRNA genome encapsidated by approximately 2000 units of the viral coat protein (CP), resulting in filamentous virions. Only few studies have examined potyvirus virions for the presence of other structural proteins. A protein linked covalently to the 5'-end of the genome has been identified in Tobacco vein mottling virus (TVMV) and Tobacco etch virus (TEV). In TEV, it is either the viral NIa protein or only its N-terminal domain (VPg) separated autocatalytically from the C-terminal proteinase domain (NIa-Pro). Virions of TVMV carry only the VPg. We examined virions of Potato virus A (PVA) for the genome-linked protein using immunoblotting or iodination and immunoprecipitation. The VPg ( approximately 25 kDa) only, and not the unprocessed NIa, was detected. Another signal corresponding to approximately 49 kDa was detected in disrupted, RNase-treated virions with anti-VPg antibodies but not with antibodies to NIa-Pro. Since it possibly represented a dimeric form of the VPg, self-interaction of the VPg was tested using the yeast two-hybrid system, which showed that the VPg self-interacts in the absence of viral RNA.
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Affiliation(s)
- I Oruetxebarria
- Department of Plant Biology, Genetic Centre, SLU, PO Box 7080, S-750 07, Uppsala, Sweden
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191
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Guo D, Chen F, Inoue K, Blount JW, Dixon RA. Downregulation of caffeic acid 3-O-methyltransferase and caffeoyl CoA 3-O-methyltransferase in transgenic alfalfa. impacts on lignin structure and implications for the biosynthesis of G and S lignin. Plant Cell 2001; 13:73-88. [PMID: 11158530 PMCID: PMC102215 DOI: 10.1105/tpc.13.1.73] [Citation(s) in RCA: 276] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2000] [Accepted: 11/09/2000] [Indexed: 05/17/2023]
Abstract
Transgenic alfalfa plants were generated harboring caffeic acid 3-O-methyltransferase (COMT) and caffeoyl CoA 3-O-methyltransferase (CCOMT) cDNA sequences under control of the bean phenylalanine ammonia-lyase PAL2 promoter. Strong downregulation of COMT resulted in decreased lignin content, a reduction in total guaiacyl (G) lignin units, a near total loss of syringyl (S) units in monomeric and dimeric lignin degradation products, and appearance of low levels of 5-hydroxy guaiacyl units and a novel dimer. No soluble monolignol precursors accumulated. In contrast, strong downregulation of CCOMT led to reduced lignin levels, a reduction in G units without reduction in S units, and increases in beta-5 linked dimers of G units. Accumulation of soluble caffeic acid beta-d-glucoside occurred only in CCOMT downregulated plants. The results suggest that CCOMT does not significantly contribute to the 3-O-methylation step in S lignin biosynthesis in alfalfa and that there is redundancy with respect to the 3-O-methylation reaction of G lignin biosynthesis. COMT is unlikely to catalyze the in vivo methylation of caffeic acid during lignin biosynthesis.
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Affiliation(s)
- D Guo
- Plant Biology Division, Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401, USA
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192
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Parvathi K, Chen F, Guo D, Blount JW, Dixon RA. Substrate preferences of O-methyltransferases in alfalfa suggest new pathways for 3-O-methylation of monolignols. Plant J 2001; 25:193-202. [PMID: 11169195 DOI: 10.1046/j.1365-313x.2001.00956.x] [Citation(s) in RCA: 58] [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] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Measurement of relative O-methyltransferase activities against all potential substrates in the monolignol pathway in developing alfalfa stem extracts revealed activities in the order: caffeoyl CoA > caffeoyl alcohol > 5-hydroxyferulic acid > caffeoyl aldehyde > 5-hydroxyconiferyl alcohol > 5-hydroxyferuloyl CoA > 5-hydroxyconiferaldehyde > caffeic acid. Maxima for all activities occurred in the seventh internode. In stem extracts from transgenic alfalfa with antisense downregulated caffeoyl CoA O-methyltransferase (CCoAOMT), activities with all substrates except for the two coenzyme A esters were unaffected. In contrast, downregulation of caffeic acid O-methyltransferase (COMT) reduced activities against the non-esterifed substrates in the order: 5-hydroxyconiferyl alcohol > 5-hydroxyferulic acid and caffeoyl alcohol > caffeoyl aldehyde > caffeic acid > 5-hydroxyconiferaldehyde. Recombinant COMT expressed in Escherichia coli exhibited the highest V(max)/K(m) values with 5-hydroxyconiferaldehyde and caffeoyl aldehyde, and the lowest with caffeic acid. These results indicate that COMT is unlikely to methylate caffeic acid during lignin biosynthesis in vivo, and provide enzymatic evidence for an alternative pathway to monolignols involving methylation of caffeoyl aldehyde and/or caffeoyl alcohol by COMT. The concept of independent pathways to guaiacyl and syringyl monolignols is discussed.
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Affiliation(s)
- K Parvathi
- Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, Oklahoma 73401, USA
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193
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Abstract
Three new bisdesmosidic saponins named conyzasaponins A, B, and C (1-3) and one new monodesmosidic saponin, conyzasaponin G (4), were isolated from the aerial parts of Conyza blinii. Their structures were elucidated on the basis of extensive NMR (DEPT, DQF-COSY, HOHAHA, HMQC, HMBC, and NOESY) and MS studies. Compounds 1-3 share a common prosapogenin, bayogenin 3-O-beta-D-xylopyranosyl-(1-->3)-beta-D-glucopyranoside, which is identical with conyzasaponin G (4), and differ in the structures of the ester-linked sugar moieties at C-28. Conyzasaponin A (1) is the 28-O-beta-D-apiofuranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl ester, conyzasaponin B (2), the 28-O-beta-D-apiofurano- syl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-[alpha-L-arabinopyranosyl-(1-->3)]-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl ester, and conyzasaponin C (3), the 28-O-alpha-L-rhamnopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-[beta-D-apiofuranosyl-(1-->3)]-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl ester of the prosapogenin, respectively.
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Affiliation(s)
- Y Su
- School of Pharmaceutical Sciences, Peking University, Beijing 100083, People's Republic of China
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194
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Fu T, Guo D, Huang X, O'Gorman MR, Huang L, Crawford SE, Soriano HE. Apoptosis occurs in isolated and banked primary mouse hepatocytes. Cell Transplant 2001; 10:59-66. [PMID: 11294473] [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: 02/19/2023] Open
Abstract
Isolation and cryopreservation of freshly isolated hepatocytes is considered a standard procedure for the long-term storage of liver cells. However, most existing methods for banking hepatocytes do not allow sufficient recovery of viable cells to meet the needs of basic research or clinical trials of hepatocyte transplantation. The mechanisms underlying this poor rate of hepatocyte recovery are unknown. Although much of the cellular damage in freezing is caused by formation of ice crystals within the cells, this is largely prevented by the use of dimethyl sulfoxide (DMSO) and controlled rate freezing. As we demonstrated recently, necrosis does occur in primary hepatocytes following isolation and cryopreservation. In the present study, we explored the contribution of apoptosis, another form of cell death, in primary hepatocytes banked for transplantation. We evaluated apoptosis of C57BL/6J mouse primary hepatocytes using several different methods. Annexin binding and the TUNEL assay, in conjunction with flow cytometry and confocal laser scanning microscopy, revealed that the percentage of apoptotic cells was dramatically elevated in cryopreserved cells compared with that in the control group of unfrozen cells. DNA laddering detected by DNA electrophoresis in agarose gel also supported the presence of apoptosis in isolated and banked liver cells. Moreover, we found that the addition of glucose (from 10 to 20 mM) into the freezing solution (University of Wisconsin Solution) decreased the rate of apoptosis by 84% and improved the cell attachment at least fourfold in cryopreserved cells. These results suggest that apoptosis might contribute to cell death in isolated and banked primary hepatocytes.
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Affiliation(s)
- T Fu
- Department of Pediatrics, Northwestern University Medical School, Children's Memorial Hospital, Chicago, IL 60614, USA
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195
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Yang Z, Guo D, Bowden MG, Sun H, Tong L, Li Z, Brown AE, Kaplan HB, Shi W. The Myxococcus xanthus wbgB gene encodes a glycosyltransferase homologue required for lipopolysaccharide O-antigen biosynthesis. Arch Microbiol 2000; 174:399-405. [PMID: 11195095 DOI: 10.1007/s002030000226] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Myxococcus xanthus is a gram-negative soil bacterium that initiates a complex developmental program in response to starvation. A transposon insertion (Tn5-lac omega109) mutant with developmental deficiencies was isolated and characterized in this study. A strain containing this insertion mutation in an otherwise wild-type background showed delayed developmental aggregation for about 12 h and sporulated at 1-2% of the wild-type level. Tn5-lac omega109 was found to have disrupted the M. xanthus wbgB gene, which is located 2.1 kb downstream of the M. xanthus lipopolysacharide (LPS) O-antigen biosynthesis genes wzm wzt wbgA. The deduced polypeptide sequence of WbgB shares significant similarity with bacterial glycosyltransferases including M. xanthus WbgA. The wbgB::Tn5-lac omega109 mutant was found to be defective in LPS O-antigen synthesis by immunochemical analysis. Further mutational analysis indicated that the defects of the wbgB::Tn5-lac omega109 mutant were not the result of polar effects on downstream genes. Various motility assays demonstrated that the Tn5-lac omega109 mutation affected both social (S) and adventurous (A) gliding motility of M. xanthus cells. The pleiotrophic effects of wbgB mutations indicate the importance of LPS O-antigen biosynthesis for various cellular functions in M. xanthus.
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Affiliation(s)
- Z Yang
- Department of Biological Sciences, Auburn University, AL 36849, USA.
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196
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Fan L, Guo D, Ma T, Wu W. [Endometrial stromal sarcoma with multi-differentiation: a study of 17 cases]. Zhonghua Bing Li Xue Za Zhi 2000; 29:432-4. [PMID: 11866946] [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: 02/23/2023]
Abstract
OBJECTIVE To investigate the clinical and pathomorphological features of multi-differentiated endometrial stromal sarcoma of the uterus and to discuss their behaviour and differential diagnosis. METHODS The histological characteristics of all cases were observed by pathological examination, some of them have been studied by immunohistochemical and/or ultrastructural techniques. RESULTS Multi-differentiation was present in 13 cases of low grade and 4 cases of high grade endometrial stromal sarcoma, of which, 13 cases had sex-cord differentiation, 10 cases had smooth muscle differentiation, osseous differentiation in 2 cases and striated muscle differentiation in 1 case. Two types of multi-differentiation was present in 9 cases. CONCLUSIONS Both low-grade and high-grade endometrial stromal sarcoma of uterus can display multi-differentiation. Sex-cord and smooth muscle differentiation are the most common types. Osseous and striated muscle differentiation are very rare. There is no definite correlation between prognosis and the amount or types of multi-differentiation components.
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Affiliation(s)
- L Fan
- Department of Pathology, The second center-hospital of Tianjin, Tianjin 300120, China
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197
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Duggan PR, Guo D, Luider J, Auer I, Klassen J, Chaudhry A, Morris D, Glück S, Brown CB, Russell JA, Stewart DA. Predictive factors for long-term engraftment of autologous blood stem cells. Bone Marrow Transplant 2000; 26:1299-304. [PMID: 11223969 DOI: 10.1038/sj.bmt.1702708] [Citation(s) in RCA: 24] [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: 11/09/2022]
Abstract
Data from 170 consecutive patients aged 19-66 years (median age 46 years) who underwent unmanipulated autologous blood stem cell transplant (ASCT) were analyzed to determine if total CD34+ cells/kg infused, CD34+ subsets (CD34+41+, CD34+90+, CD34+33-, CD34+38-, CD34+38-DR-), peripheral blood CD34+ cell (PBCD34+) count on first apheresis day, or various clinical factors were associated with low blood counts 6 months post ASCT. Thirty-four patients were excluded from analysis either because of death (n = 17) or re-induction chemotherapy prior to 6 months post ASCT (n = 13), or because of lack of follow-up data (n = 4). Of the remaining 136 patients, 46% had low WBC ( < 4 x 10(9)/l), 41% low platelets (<150 x 10(9)/l), and 34% low hemoglobin ( < 120 g/l) at a median of 6 months following ASCT. By Spearman's rank correlation, both the total CD34+ cell dose/kg and the PBCD34+ count correlated with 6 month blood counts better than any subset of CD34+ cells or any clinical factor. The PBCD34+ count was overall a stronger predictor of 6 month blood counts than was the total CD34+ cells/kg infused. Both factors retained their significance in multivariate analysis, controlling for clinical factors. In conclusion, subsets of CD34+ cells and clinical factors are inferior to the total CD34+ cell dose/kg and PBCD34+ count in predicting 6 month blood counts following ASCT.
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Affiliation(s)
- P R Duggan
- Department of Medicine, Tom Baker Cancer Center, Foothills Hospital, and University of Calgary, Calgary, Alberta, Canada
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198
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Perianayagam MC, Murray SL, Balakrishnan VS, Guo D, King AJ, Pereira BJ, Jaber BL. Serum soluble Fas (CD95) and Fas ligand profiles in chronic kidney failure. J Lab Clin Med 2000; 136:320-7. [PMID: 11039853 DOI: 10.1067/mlc.2000.109318] [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] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Apoptosis, or programmed cell death, is an active form of cell death that is initiated by a number of stimuli and is intricately regulated. Apoptosis in both excessive and reduced amounts has pathophysiologic implications. Accelerated programmed cell death has been observed in leukocytes among patients with chronic renal failure (CRF). This has been ascribed in part to the retention of uremic toxins. The Fas/Fas ligand (FasL) system is a key regulatory apoptotic pathway. Membrane-bound Fas is a cell-surface receptor that transduces apoptosis after interaction with membrane-bound or soluble FasL (sFasL). By contrast, soluble Fas (sFas) binds sFasL and inhibits its activity. In an attempt to examine the balance between these soluble factors in uremia, we measured soluble sFas and sFasL levels in the serum of healthy control subjects and patients with various degrees of CRF and examined the distribution of the various molecular mass fractions of these proteins in uremic serum. In brief, serum was obtained from 15 healthy volunteers, 17 patients with CRF, 11 patients undergoing maintenance hemodialysis (HD), and 7 patients undergoing peritoneal dialysis (PD). Serum sFas and sFasL were measured by enzyme-linked immunosorbent assay, and their molecular distribution was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by immunoblot. Compared with results in healthy control subjects, sFas levels were significantly higher in patients with CRF and in patients undergoing dialysis. There was a significant inverse correlation between sFas levels and creatinine clearance. Serum sFasL levels were not different among the four groups. However, the sFas-to-sFasL ratio was significantly lower in healthy control subjects as compared with patients with CRF and patients undergoing dialysis. Immunoblots and densitometric analyses of sFas and sFasL depicted a known 48-kd sFas, a known 27-kd sFasL, and a 60-kd sFas-sFasL protein aggregate signal. In conclusion, serum sFas levels are increased in patients with various degrees of CRF and may bind circulating sFasL, thereby minimizing mediation of cellular apoptosis.
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Affiliation(s)
- M C Perianayagam
- Tupper Research Institute, Department of Medicine, New England Medical Center, Boston, MA 02111, USA
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199
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Stewart DA, Guo D, Glück S, Morris D, Chaudhry A, deMetz C, Klassen J, Brown CB, Russell JA. Double high-dose therapy for Hodgkin's disease with dose-intensive cyclophosphamide, etoposide, and cisplatin (DICEP) prior to high-dose melphalan and autologous stem cell transplantation. Bone Marrow Transplant 2000; 26:383-8. [PMID: 10982284 DOI: 10.1038/sj.bmt.1702541] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We previously reported a 50% (95% CI = 33-76%) 5 year event-free survival (EFS) rate for 23 patients with Hodgkin's disease (HD) who received salvage therapy with single agent high-dose melphalan (HDM) and autologous stem cell transplantation (ASCT). Predictors of poor outcome included bulky disease and initial remission <1 year. Since 1995, similar poor prognosis patients have been treated with double high-dose therapy consisting of dose-intensive cyclophosphamide 5.25 g/m2, etoposide 1.05 g/m2, cisplatin 105 mg/m2 (DICEP) for tumor cytoreduction and stem cell mobilization followed by HDM/ASCT. The purpose of the present study is to determine if the use of DICEP is associated with improved event-free (EFS) and overall survival (OAS) for patients treated with HDM/ASCT. From February 1981 to June 1999, 46 consecutive patients received HDM/ASCT for relapsed (n = 35) or refractory (n = 11) HD. DICEP re-induction and blood stem cell mobilization was used for 21 patients. Factors considered for univariate and multivariate analyses included age at transplant, number of failed chemotherapy regimens, prior radiotherapy, length of initial remission, relapsed or refractory disease status, extranodal relapse, B symptoms at relapse, bulk, post-ASCT radiotherapy, and DICEP re-induction therapy. Cox proportional hazards models were constructed for both event and death. DICEP and HDM were well tolerated with no early treatment-related mortality or toxicity requiring life-sustaining measures. For all 46 patients, the projected 5 year EFS was 52% (95% CI = 38-72%) and OAS was 57% (95% CI = 40-82). Factors independently associated with relapse in multivariate analysis included bulk >5 cm (RR = 6.38, P = 0.002), prior radiotherapy (RR = 3.59, P = 0.027), and not using DICEP (RR = 5.29, P = 0.005). Factors independently associated with death included bulk >5 cm (RR = 5.13, P = 0.009), > or =3 prior chemotherapy regimens (RR = 4.72, P = 0.019), and not using DICEP (RR = 7.49, P = 0.015). This study demonstrates that DICEP re-induction prior to HDM/ASCT is feasible. The preliminary data are sufficiently encouraging to warrant a multicenter phase II or a phase III trial evaluating DICEP followed by HDM/ASCT as salvage therapy for HD.
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Affiliation(s)
- D A Stewart
- Department of Medicine, Tom Baker Cancer Centre, Foothills Hospital and University of Calgary, Alberta, Canada
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200
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Abstract
Starvation and cell density regulate the developmental expression of Myxococcus xanthus gene 4521. Three classes of mutants allow expression of this developmental gene during growth on nutrient agar, such that colonies of strains containing a Tn5 lac Omega4521 fusion are Lac(+). One class of these mutants inactivates SasN, a negative regulator of 4521 expression; another class activates SasS, a sensor kinase-positive regulator of 4521 expression; and a third class blocks lipopolysaccharide (LPS) O-antigen biosynthesis. To identify additional positive regulators of 4521 expression, 11 Lac(-) TnV. AS transposon insertion mutants were isolated from a screen of 18,000 Lac(+) LPS O-antigen mutants containing Tn5 lac Omega4521 (Tc(r)). Ten mutations identified genes that could encode positive regulators of 4521 developmental expression based on their ability to abolish 4521 expression during development in the absence of LPS O antigen and in an otherwise wild-type background. Eight of these mutations mapped to the sasB locus, which encodes the known 4521 regulators SasS and SasN. One mapped to sasS, whereas seven identified new genes. Three mutations mapped to a gene encoding an NtrC-like response regulator homologue, designated sasR, and four others mapped to a gene designated sasP. One mutation, designated ssp10, specifically suppressed the LPS O-antigen defect; the ssp10 mutation had no effect on 4521 expression in an otherwise wild-type background but reduced 4521 developmental expression in the absence of LPS O antigen to a level close to that of the parent strain. All of the mutations except those in sasP conferred defects during growth and development. These data indicate that a number of elements are required for 4521 developmental expression and that most of these are necessary for normal growth and fruiting body development.
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Affiliation(s)
- D Guo
- Department of Microbiology and Molecular Genetics, The University of Texas-Houston Medical School, Houston, Texas 77030, USA
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