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Pei J, Sterzik K, Strehler E, El-Danasouri I, Paulus WE. Effect of Pregnancy Outcome after Acupuncture on Point Selected by Infrared Thermography on the Day of Embryo Transfer*. Geburtshilfe Frauenheilkd 2008. [DOI: 10.1055/s-0028-1088874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Paulus WE, Pei J, Strehler E, Fißeler K, Hütter W, Sterzik K. Der Einfluss von Ginkgo biloba – Extrakt auf die uterine Perfusion bei Sterilitätspatientinnen. Geburtshilfe Frauenheilkd 2006. [DOI: 10.1055/s-2006-952857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Pei J, Strehler E, Noss U, Abt M, Piomboni P, Baccetti B, Sterzik K. Quantitative Evaluation of Spermatozoa Ultrastructure After Acupuncture Treatment for Idiopathic Male Infertility. J Urol 2006. [DOI: 10.1016/s0022-5347(05)00443-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Zielenska M, Marrano P, Thorner P, Pei J, Beheshti B, Ho M, Bayani J, Liu Y, Sun BC, Squire JA, Hao XS. High-resolution cDNA microarray CGH mapping of genomic imbalances in osteosarcoma using formalin-fixed paraffin-embedded tissue. Cytogenet Genome Res 2005; 107:77-82. [PMID: 15305059 DOI: 10.1159/000079574] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2004] [Accepted: 04/01/2004] [Indexed: 11/19/2022] Open
Abstract
Formalin-fixed paraffin embedded (FFPE) tumor tissue provides an opportunity to perform retrospective genomic studies of tumors in which chromosomal imbalances are strongly associated with oncogenesis. The application of comparative genomic hybridization (CGH) has led to the rapid accumulation of cytogenetic information on osteosarcoma (OS); however, the limited resolving power of metaphase CGH does not permit precise mapping of imbalances. Array CGH allows quantitative detection and more precise delineation of copy number aberrations in tumors. Unfortunately the high cost and lower density of BACs on available commercial arrays has limited the ability to comprehensively profile copy number changes in tumors such as OS that are recurrently subject to genomic imbalance. In this study a cDNA/EST microarray including 18,980 human cDNAs (which represent all 22 pairs of autosomal chromosomes and chromosome X) was used for CGH analysis of eight OS FFPE. Chromosomes 1, 12, 17, and X harbored the most imbalances. Gain/amplification of X was observed in 4/8 OS, and in keeping with other recent genomic analyses of OS, gain/amplification of 17p11.2 was often accompanied by a distal deletion in the region of the p53 gene. Gain/amplification of the X chromosome was verified using interphase FISH carried out on a subset of OS FFPE sections and OS tissue arrays.
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Chau CH, Shum DKY, Li H, Pei J, Lui YY, Wirthlin L, Chan YS, Xu XM. Chondroitinase ABC enhances axonal regrowth through Schwann cell-seeded guidance channels after spinal cord injury. FASEB J 2003; 18:194-6. [PMID: 14630702 DOI: 10.1096/fj.03-0196fje] [Citation(s) in RCA: 147] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Grafting of Schwann cell-seeded channels into hemisected adult rat thoracic spinal cords has been tested as a strategy to bridge the injured cord. Despite success in guiding axonal growth into the graft, regeneration across the distal graft-host interface into the host spinal cord was limited. We hypothesized that chondroitin sulfate (CS) glycoforms deposited at the gliotic front of the interface constitute a molecular barrier to axonal growth into the host cord. Because CS glycoforms deposited by purified astrocytes in vitro were removable by digestion with chondroitinase ABC, we attempted to achieve likewise by infusion of the enzyme to the host side of the interface. By 1 month post-treatment, significant numbers of regenerating axons crossed an interface that was subdued in macrophage/microglia reaction and decreased in CS-immunopositivity. The axons extended as far into the caudal cord as 5 mm, in contrast to nil in vehicle-infused controls. Fascicular organizations of axon-Schwann cell units within the regenerated tissue cable were better-preserved in enzyme-treated cords than in vehicle-infused controls. We conclude that CS glycoforms deposited during gliosis at the distal graft-host interface could be cleared by the in vivo action of chondroitinase ABC to improve prospects of axonal regeneration into the host spinal cord.
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Chen J, Pei J, Quan X, Zhao Y, Chen S, Schramm KW, Kettrup A. Linear free energy relationships on rate constants for dechlorination by zero-valent iron. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2002; 13:597-606. [PMID: 12479374 DOI: 10.1080/1062936021000020053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
By correlation analysis, molecular structural factors governing surface area-normalized rate constants (k) for dechlorination by zero-valent iron, were identified. Twenty-nine quantum chemical descriptors computed by MNDO, AM1 and PM3 Hamiltonians for gas-phase and the conductor-like screening model (COSMO) for incorporating solvent (H2O) effects were studied. Besides the energy of the lowest unoccupied molecular orbital (E(LUMO)), the character of carbon-chlorine bonds (C-Cl bonds) and especially the strength of C-Cl bonds was found significant in governing the magnitude of log k. By PLS analysis, six two-parameter linear free energy relationships (LFER) were obtained. The best two-parameter LFER model was the one using E(LUMO) and C (the Coulombic interaction energy of the two-center term for the C-Cl bonds) computed by PM3/H2O method as molecular structural descriptors. Chlorinated compounds with high E(LUMO) and C values tend to have low dechlorination rate constants.
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Gallagher M, Pei J, Youngs D, Hamilton K, Yadock W, Dieterich S, Lagasca R, Mickelson E, Marsh C, Hansen J, Nelson K. Donor-specific hyporesponsiveness measured by CTLP and CFSE dye dilution. Hum Immunol 2002. [DOI: 10.1016/s0198-8859(02)00509-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
To accommodate situations in which the 3D structure of the target receptor is not available, we have developed the Pseudo Atomic Receptor Model (PARM) software package. In this article we describe PARM and illustrate its use with three examples: elemenes (potential anticancer drugs), angiotensin converting enzyme inhibitors, and human HIV-1 inhibitors TTD (1,1,3-trioxo-2H, 4H-thieno[3,4-e][1,2,4] thiadiazine derivatives). The results show that PARM can build models with favorable cross-validation statistics (Rcv2 values 0.7-0.9) and give helpful SAR insight. PARM has certain advantages: (a) it can be used for many systems, regardless of whether the 3D structure of the receptor is known; (b) PARM models were demonstrated to be highly statistically reliable; and (c) PARM analyses are robust and reproducible.
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Pei J, Akatsuka Y, Anasetti C, Lin MT, Petersdorf EW, Hansen JA, Martin PJ. Generation of HLA-C-specific cytotoxic T cells in association with marrow graft rejection: analysis of alloimmunity by T-cell cloning and testing of T-cell-receptor rearrangements. Biol Blood Marrow Transplant 2002; 7:378-83. [PMID: 11529487 DOI: 10.1053/bbmt.2001.v7.pm11529487] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Peripheral blood mononuclear cells from a patient who rejected a T-cell-depleted marrow graft showed spontaneous cytotoxic activity specific for HLA-Cw4 and HLA-B35 alloantigens of the donor. T-cell-receptor complementarity-determining region 3 length distributions in a blood sample obtained at the time of rejection generally showed distortions in only 1 or 2 peaks, indicating that recipient T cells with a broad repertoire of antigen receptors survived the pretransplantation conditioning regimen. An HLA-Cw4-specific, CD8 T-cell clone was recovered from a blood sample after rejection. The T-cell-receptor-B gene rearrangement expressed by this clone was not readily detectable in other blood samples drawn before or after the transplantation, indicating that this clone was only 1 of many recipient-derived T cells that recognized HLA alloantigens of the donor. These results demonstrate the role of the HLA-C locus in T-cell-mediated alloimmune responses and add to emerging evidence that indicates the need to evaluate HLA-C compatibility in selecting hematopoietic stem cell donors for patients who have an increased risk of rejection.
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Pei J, Sekellick MJ, Marcus PI, Choi IS, Collisson EW. Chicken interferon type I inhibits infectious bronchitis virus replication and associated respiratory illness. J Interferon Cytokine Res 2001; 21:1071-7. [PMID: 11798465 DOI: 10.1089/107999001317205204] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Infectious bronchitis virus (IBV) causes an economically important respiratory disease in poultry worldwide. Previous studies have shown that CD8(+) cytotoxic T lymphocytes (CTL) are critical in controlling acute IBV infection, but the role of innate immunity is unknown. This study describes the in vitro and in vivo anti-IBV activity of natural spleen cell-derived and recombinant chicken interferon type I (rChIFN-alpha). Both natural and rChIFN-alpha inhibited replication of the Beaudette strain of IBV in chicken kidney cells (CKC) in a dose-dependent manner, with the antiviral activity of the former accounted for entirely by its content of type I IFN. IFN at 100 U/ml reduced viral replication by 50% as measured by syncytia formation. In addition, the spleen cell-derived supernatants (natural IFN) inhibited tracheal ring ciliostasis mediated by the Gray strain of IBV. Optimal protection against IBV-induced respiratory disease was obtained after intravenous or oral administration of ChIFN given 1 day before virus challenge and each of 5 days thereafter. ChIFN-I protected chicks from clinical illness by delaying the onset of the disease and decreasing the severity of illness, demonstrating its potential as an immune enhancer.
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Pei J, Sun L, Chen R, Zhu T, Qian Y, Yuan D. The effect of electro-acupuncture on motor function recovery in patients with acute cerebral infarction: a randomly controlled trial. J TRADIT CHIN MED 2001; 21:270-2. [PMID: 12014128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
UNLABELLED The aim of this study is to investigate the effect of electro-acupuncture treatment in acute phase of cerebral infarction on the motor functions. In this randomly controlled trial, 86 patients were allocated to two groups, the experimental group given clinical and electro-acupuncture treatments for a period of 4 weeks, and the control group given clinical treatment plus active and/or passive functional exercise. The result showed that the level of impairment and disability in both groups were improvement according to the Chinese Stroke Scale, Brunnstrom-Fugl-Meyer score, and Barthel Index throughout the study and 3 months after. The motor functions and the activities of daily living (ADL) were improved significantly in the electro-acupuncture group as compared with the control group (P < 0.05). Also, the results showed greater reduction of neurological deficit in the electro-acupuncture group than in the control group. CONCLUSION Early acupuncture treatment for acute stroke patients may improve motor functions, and consequently the activities of daily living.
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Abbott JJ, Pei J, Ford JL, Qi Y, Grishin VN, Pitcher LA, Phillips MA, Grishin NV. Structure prediction and active site analysis of the metal binding determinants in gamma -glutamylcysteine synthetase. J Biol Chem 2001; 276:42099-107. [PMID: 11527962 DOI: 10.1074/jbc.m104672200] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
gamma-Glultamylcysteine synthetase (gamma-GCS) catalyzes the first step in the de novo biosynthesis of glutathione. In trypanosomes, glutathione is conjugated to spermidine to form a unique cofactor termed trypanothione, an essential cofactor for the maintenance of redox balance in the cell. Using extensive similarity searches and sequence motif analysis we detected homology between gamma-GCS and glutamine synthetase (GS), allowing these proteins to be unified into a superfamily of carboxylate-amine/ammonia ligases. The structure of gamma-GCS, which was previously poorly understood, was modeled using the known structure of GS. Two metal-binding sites, each ligated by three conserved active site residues (n1: Glu-55, Glu-93, Glu-100; and n2: Glu-53, Gln-321, and Glu-489), are predicted to form the catalytic center of the active site, where the n1 site is expected to bind free metal and the n2 site to interact with MgATP. To elucidate the roles of the metals and their ligands in catalysis, these six residues were mutated to alanine in the Trypanosoma brucei enzyme. All mutations caused a substantial loss of activity. Most notably, E93A was able to catalyze the l-Glu-dependent ATP hydrolysis but not the peptide bond ligation, suggesting that the n1 metal plays an important role in positioning l-Glu for the reaction chemistry. The apparent K(m) values for ATP were increased for both the E489A and Q321A mutant enzymes, consistent with a role for the n2 metal in ATP binding and phosphoryl transfer. Furthermore, the apparent K(d) values for activation of E489A and Q321A by free Mg(2+) increased. Finally, substitution of Mn(2+) for Mg(2+) in the reaction rescued the catalytic deficits caused by both mutations, demonstrating that the nature of the metal ligands plays an important role in metal specificity.
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Wang X, Tan X, Pei J, Zheng P. [A lumped parameter model of the peripheral extra-corporeal circulation]. SHENG WU YI XUE GONG CHENG XUE ZA ZHI = JOURNAL OF BIOMEDICAL ENGINEERING = SHENGWU YIXUE GONGCHENGXUE ZAZHI 2001; 18:366-8, 407. [PMID: 11605490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
A three-element model of lumped parameter in peripheral extra-corporeal circulation of an animal has been proposed and set up according to the fluid network theory. GEAR method, appropriate for the computation of the rigid problems, was used to solve the ordinary differential equations, so that a good convergence of the solution to the equations has been achieved. Physiological data of a 20 kg dog, obtained from our animal experiments were used to calculate the pressure and flow rate of important organs. The results of the mathematical model and animal tests showed that the peripheral extra-corporeal circulation could supply enough blood to the important organs, e.g. heart and brain, when the natural heart beating stopped. The results from both theoretical and experiments are critical to the cardiopulmonary cerebral resuscitation for the animals as well as for human beings.
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Gokhale PC, Pei J, Zhang C, Ahmad I, Rahman A, Kasid U. Improved safety, pharmacokinetics and therapeutic efficacy profiles of a novel liposomal formulation of mitoxantrone. Anticancer Res 2001; 21:3313-21. [PMID: 11848489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
We describe here the preclinical studies of a novel formulation of liposome-entrapped mitoxantrone (LEM). The liposome entrapment efficiency of mitoxantrone was 93.4 +/- 2.8%. In vitro cytotoxicity studies in HL60 cells comparing LEM with conventional mitoxantrone (MTO) showed IC50 values of 0.31 +/- 0.05 ng/ml and 0.48 +/- 0.06 ng/ml for LEM and MTO, respectively. In CD2F1 mice, LEM was significantly less toxic as compared with MTO. A single intravenous (i.v.) dose of 15 mg/kg MTO produced 100% mortality in CD2F1 mice by Day 10, whereas a single i.v. dose as high as 35 mg/kg LEM caused no mortality for at least up to Day 60 post-treatment. Multiple doses of MTO (i.v., 5.0 mg/kg, 1x daily, x5) caused 100% mortality by Day 10, whereas a similar dose regimen of LEM caused no mortality in CD2F1 mice. Clinical and histopathology evaluations indicated long-term normal tissue protection in mice treated with relatively high single dose (i.v., 35 mg/kg) or multiple doses of LEM (i.v., 5.0 mg/kg, 1x daily, x5). LEM also demonstrated favourable pharmacokinetic profiles. CD2F1 mice injected with 5 mg/kg i.v. dose of LEM showed plasma levels 51-fold higher than with an equivalent dose of MTO. The area under the plasma concentration-time curve was 200-fold greater with LEM as compared to MTO. The plasma half-lives were 0.96 hours and 0.11 hours for LEM and MTO, respectively. An altered tissue distribution was observed with LEM; cardiac tissue demonstrating at least 2.6-fold lower levels of mitoxantrone with LEM vs. MTO. LEM exhibited significant anti-tumor activity against murine ascitic L1210 leukemia in CD2F1 mice. Treatment with a single dose of 20.0 mg/kg LEM resulted in 100% long-term survivors. LEM 2.5 mg/kg (i.v., x4) had antitumor activity against a human hormone-independent prostate carcinoma (PC-3) grown in athymic mice, while a comparable dose of MTO was too toxic. A significant decrease in toxicity, altered pharmacokinetics, and enhanced efficacy of LEM suggest that LEM may provide a viable alternative to the clinical use of conventional mitoxantrone.
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Abstract
MOTIVATION Amino acid sequence alignments are widely used in the analysis of protein structure, function and evolutionary relationships. Proteins within a superfamily usually share the same fold and possess related functions. These structural and functional constraints are reflected in the alignment conservation patterns. Positions of functional and/or structural importance tend to be more conserved. Conserved positions are usually clustered in distinct motifs surrounded by sequence segments of low conservation. Poorly conserved regions might also arise from the imperfections in multiple alignment algorithms and thus indicate possible alignment errors. Quantification of conservation by attributing a conservation index to each aligned position makes motif detection more convenient. Mapping these conservation indices onto a protein spatial structure helps to visualize spatial conservation features of the molecule and to predict functionally and/or structurally important sites. Analysis of conservation indices could be a useful tool in detection of potentially misaligned regions and will aid in improvement of multiple alignments. RESULTS We developed a program to calculate a conservation index at each position in a multiple sequence alignment using several methods. Namely, amino acid frequencies at each position are estimated and the conservation index is calculated from these frequencies. We utilize both unweighted frequencies and frequencies weighted using two different strategies. Three conceptually different approaches (entropy-based, variance-based and matrix score-based) are implemented in the algorithm to define the conservation index. Calculating conservation indices for 35522 positions in 284 alignments from SMART database we demonstrate that different methods result in highly correlated (correlation coefficient more than 0.85) conservation indices. Conservation indices show statistically significant correlation between sequentially adjacent positions i and i + j, where j < 13, and averaging of the indices over the window of three positions is optimal for motif detection. Positions with gaps display substantially lower conservation properties. We compare conservation properties of the SMART alignments or FSSP structural alignments to those of the ClustalW alignments. The results suggest that conservation indices should be a valuable tool of alignment quality assessment and might be used as an objective function for refinement of multiple alignments. AVAILABILITY The C code of the AL2CO program and its pre-compiled versions for several platforms as well as the details of the analysis are freely available at ftp://iole.swmed.edu/pub/al2co/.
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Pei J, Balsara BR, Li W, Litwin S, Gabrielson E, Feder M, Jen J, Testa JR. Genomic imbalances in human lung adenocarcinomas and squamous cell carcinomas. Genes Chromosomes Cancer 2001; 31:282-7. [PMID: 11391799 DOI: 10.1002/gcc.1145] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Comparative genomic hybridization analysis was performed on 67 non-small-cell lung cancers (NSCLCs), including 32 squamous cell carcinomas (SCCs) and 35 adenocarcinomas (ACs), to identify differences in the patterns of genomic imbalance between these two histologic subtypes. Among the entire tumor set, the chromosome arms most often overrepresented were 1q, 3q, 5p, and 8q, each detected in 50-55% of cases. The most frequently underrepresented arms were 9q, 3p, 8p, and 17p. The number of imbalances was similar in SCCs and ACs (median number/case: 12 and 11, respectively). Moreover, many imbalances, such as gains of 1q, 5p, and 8q, occurred at a high frequency in both histologic subgroups. Several statistically significant differences, however, were found. The most prominent difference was gain of 3q24-qter, seen in 81% of SCCs compared with 31% of ACs (P < 0.0001), with amplification at 3q25-26 being detected in eight of 32 (25%) SCCs but in only two of 35 (6%) ACs. Gain of 20p13 and loss of 4q also were seen at a significantly higher rate in SCCs than in ACs, whereas overrepresentation of 6p was more common in ACs. Gains of 7q and 8q each were associated with higher-stage tumors and either positive nodal involvement or higher tumor grade. These data suggest that genes located in several chromosomal regions, particularly 3q25-26, may be associated with phenotypic properties that differentiate lung SCCs from ACs. Furthermore, certain imbalances, prominent among them gains of 7q and 8q, may be indicative of tumor aggressiveness in NSCLCs.
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MESH Headings
- Adenocarcinoma/genetics
- Carcinoma, Non-Small-Cell Lung/genetics
- Carcinoma, Squamous Cell/genetics
- Chromosome Aberrations/genetics
- Chromosome Deletion
- Chromosomes, Human, Pair 1/genetics
- Chromosomes, Human, Pair 3/genetics
- Chromosomes, Human, Pair 5/genetics
- Chromosomes, Human, Pair 8/genetics
- Gene Amplification/genetics
- Humans
- Lung Neoplasms/genetics
- Nucleic Acid Hybridization
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Pei J, Tercier-Waeber ML, Buffle J, Fiaccabrino GC, Koudelka-Hep M. Individually addressable gel-integrated voltammetric microelectrode array for high-resolution measurement of concentration profiles at interfaces. Anal Chem 2001; 73:2273-81. [PMID: 11393852 DOI: 10.1021/ac000615e] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The application of a novel voltammetric probe, based on an individually addressable gel-integrated microelectrode array (IA-GIME), for real-time, high-spatial resolution concentration profile measurements at interfaces is described. Reliability and validity of steep metal concentration gradients obtained with this novel system have been demonstrated by performing systematic tests at well-controlled liquid-liquid and liquid-solid interfaces. The liquid-liquid interface was formed by two layers of aqueous solutions with different components; only one layer contained trace metal ions (Pb(II) and Cd(II)); the individually addressable microelectrode array was placed at the interface of the liquid-liquid system; the concentration profiles were recorded as function of time; and the effective diffusion coefficients were calculated. The liquid-"solid" interface was formed from an aqueous solution layer overlying a bed of silica particles saturated with an aqueous solution. The sensor array has been used to monitor the diffusion processes of Tl(I) or Pb(II) from the liquid phase to the "solid" phase. The influences of porosity, geometry of the porous media, and complexation between metal ion and silica, on the diffusion processes, have been studied. All these results show that correct diffusion profiles of metal ions at interfaces can be obtained with 200-microm resolution with the IA-GIME. They also demonstrate that, for measurements in "solid" phase, the aforementioned factors must be considered carefully for correct calibration of any electrodes and the gel-integrated microelectrodes are unique tools to enable calibration of the sensors with synthetic solutions.
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Pei J, Grishin NV. Type II CAAX prenyl endopeptidases belong to a novel superfamily of putative membrane-bound metalloproteases. Trends Biochem Sci 2001; 26:275-7. [PMID: 11343912 DOI: 10.1016/s0968-0004(01)01813-8] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
In this article, a novel, large and diverse superfamily of putative membrane-bound proteins that includes the type II CAAX prenyl endopeptidases is described. The majority of the members of this superfamily are hypothetical proteins from bacteria and plants. Analysis of the conserved motifs, combined with available experimental data, suggests that these proteins are putative metal-dependent proteases that are potentially involved in protein and/or peptide modification and secretion.
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Balsara BR, Pei J, De Rienzo A, Simon D, Tosolini A, Lu YY, Shen FM, Fan X, Lin WY, Buetow KH, London WT, Testa JR. Human hepatocellular carcinoma is characterized by a highly consistent pattern of genomic imbalances, including frequent loss of 16q23.1-24.1. Genes Chromosomes Cancer 2001; 30:245-53. [PMID: 11170281 DOI: 10.1002/1098-2264(2000)9999:9999<::aid-gcc1083>3.0.co;2-m] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Comparative genomic hybridization (CGH) analysis was used to identify chromosomal imbalances in 52 human primary hepatocellular carcinomas (HCCs). The most prominent changes were gains of part or all of chromosome arms 8q (83% of cases) and 1q (73%) and loss of 16q (63%). Other commonly overrepresented sites were 5p, 7q, and Xq. Recurrent sites of DNA sequence amplification included 8q23--24 (five cases) and 11q13--14 (four cases). Other frequently underrepresented sites were 4q, 8p, 16p, and 17p. Taken collectively, these findings and data from other CGH studies of HCCs define a subset of chromosome segments that are consistently over- or underrepresented and highlight sites of putative oncogenes and tumor suppressor genes, respectively, involved in hepatocellular oncogenesis. Loss of heterozygosity analysis with a panel of polymorphic microsatellite markers distributed along 16q defined a minimal region of chromosomal loss at 16q23.1--24.1, suggesting that this region harbors a tumor suppressor gene whose loss/inactivation may contribute to the pathogenesis of many HCCs.
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Abstract
The GGDEF domain is detected in many prokaryotic proteins, most of which are of unknown function. Several bacteria carry 12-22 different GGDEF homologues in their genomes. Conducting extensive profile-based searches, we detect statistically supported sequence similarity between GGDEF domain and adenylyl cyclase catalytic domain. From this homology, we deduce that the prokaryotic GGDEF domain is a regulatory enzyme involved in nucleotide cyclization, with the fold similar to that of the eukaryotic cyclase catalytic domain. This prediction correlates with the functional information available on two GGDEF-containing proteins, namely diguanylate cyclase and phosphodiesterase A of Acetobacter xylinum, both of which regulate the turnover of cyclic diguanosine monophosphate. Domain architecture analysis shows that GGDEF is typically present in multidomain proteins containing regulatory domains of signaling pathways or protein-protein interaction modules. Evolutionary tree analysis indicates that GGDEF/cyclase superfamily forms a large diversified cluster of orthologous proteins present in bacteria, archaea, and eukaryotes. Proteins 2001;42:210-216.
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Abstract
The GGDEF domain is detected in many prokaryotic proteins, most of which are of unknown function. Several bacteria carry 12-22 different GGDEF homologues in their genomes. Conducting extensive profile-based searches, we detect statistically supported sequence similarity between GGDEF domain and adenylyl cyclase catalytic domain. From this homology, we deduce that the prokaryotic GGDEF domain is a regulatory enzyme involved in nucleotide cyclization, with the fold similar to that of the eukaryotic cyclase catalytic domain. This prediction correlates with the functional information available on two GGDEF-containing proteins, namely diguanylate cyclase and phosphodiesterase A of Acetobacter xylinum, both of which regulate the turnover of cyclic diguanosine monophosphate. Domain architecture analysis shows that GGDEF is typically present in multidomain proteins containing regulatory domains of signaling pathways or protein-protein interaction modules. Evolutionary tree analysis indicates that GGDEF/cyclase superfamily forms a large diversified cluster of orthologous proteins present in bacteria, archaea, and eukaryotes. Proteins 2001;42:210-216.
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Xu Y, Wu J, Pei J, Shi Y, Ji Y, Tong Q. Solution structure of BmP02, a new potassium channel blocker from the venom of the Chinese scorpion Buthus martensi Karsch. Biochemistry 2000; 39:13669-75. [PMID: 11076505 DOI: 10.1021/bi000860s] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BmP02 is a 28-amino acid residue peptide purified from the venom of the Chinese scorpion Buthus martensi Karsch, which had been demonstrated to be a weak blocker of apamin-sensitive calcium-activated potassium channels. Two-dimensional NMR spectroscopy techniques were used to determine the solution structure of BmP02. The results show that BmP02 formed a alpha/beta scorpion fold, the typical three-dimensional structure adopted by most short chain scorpion toxins whose structures have been determined. However, in BmP02 this alpha/beta fold was largely distorted. The alpha-helix was shortened to only one turn, and the loop connecting the helix to the first beta-strand exhibited conformational heterogeneity. The instability of BmP02 could be attributed to a proline at position 17, which is usually a glycine. Because the residue at this position makes intense contact with the alpha-helix, it was supposed that the bulky side chain of proline had pushed the helix away from the beta-sheet. This had a significant influence on the structure and function of BmP02. The alpha-helix rotated by about 40 degrees to avoid Pro17 while forming two disulfides with the second beta-strand. The rotation further caused both ends of the helix to be unwound due to covalent restrictions. According to its structure, BmP02 was supposed to interact with its target via the side chains of Lys11 and Lys13.
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Pei J, Li X. Determination of underivatized amino acids by high-performance liquid chromatography and electrochemical detection at an amino acid oxidase immobilized CuPtCI6 modified electrode. FRESENIUS' JOURNAL OF ANALYTICAL CHEMISTRY 2000; 367:707-13. [PMID: 11220604 DOI: 10.1007/s002160000447] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
An amperometric sensor for amino acids based on the immobilization of amino acid oxidase on the surface of a CuPtCl(6)/GC is described. The amperometric current is due to the oxidation of H2O2 liberated during the enzyme reaction on the surface of the enzyme electrode. The electrode response characteristics as well as kinetic parameters have been evaluated. The enzyme electrode was characterized as an electrochemical biosensor, which was used as detector in high performance liquid chromatography (HPLC) for the determination of a mixture of amino acids with satisfactory results.
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Lin MT, Tseng LH, Frangoul H, Gooley T, Pei J, Barsoukov A, Akatsuka Y, Hansen JA. Increased apoptosis of peripheral blood T cells following allogeneic hematopoietic cell transplantation. Blood 2000; 95:3832-9. [PMID: 10845917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Lymphopenia and immune deficiency are significant problems following allogeneic hematopoietic cell transplantation (HCT). It is largely assumed that delayed immune reconstruction is due to a profound decrease in thymus-dependent lymphopoiesis, especially in older patients, but apoptosis is also known to play a significant role in lymphocyte homeostasis. Peripheral T cells from patients who received HCT were studied for evidence of increased cell death. Spontaneous apoptosis was measured in CD3(+) T cells following a 24-hour incubation using 7-amino-actinomycin D in conjunction with the dual staining of cell surface antigens. Apoptosis was significantly greater among CD3(+) T cells taken from patients 19-23 days after transplantation (30.4% +/- 12.5%, P <.05), and 1 year after transplantation (9.7% +/- 2.8%, P <.05) compared with healthy controls (4.0% +/- 1.5%). Increased apoptosis occurred preferentially in HLA (human leukocyte antigen)-DR positive cells and in both CD3(+)/CD4(+) and CD3(+)/CD8(+) T-cell subsets, while CD56(+)/CD3(-) natural killer cells were relatively resistant to apoptosis. The extent of CD4(+) T-cell apoptosis was greater in patients with grade II-IV acute graft-versus-host disease (GVHD) (33. 9% +/- 11.3%) compared with grade 0-I GVHD (14.6 +/- 6.5%, P <.05). T-cell apoptosis was also greater in patients who received transplantations from HLA-mismatched donors (39.5% +/- 10.4%, P <. 05) or HLA-matched unrelated donors (32.1% +/- 11.4%, P <.05) compared with patients who received transplantations from HLA-identical siblings (19.6% +/- 6.7%). The intensity of apoptosis among CD4(+) T cells was significantly correlated with a lower CD4(+) T-cell count. Together, these observations suggest that activation of T cells in vivo, presumably by alloantigens, predisposes the cells to spontaneous apoptosis, and this phenomenon is associated with lymphopenia. Activation-induced T-cell apoptosis may contribute to delayed immune reconstitution following HCT. (Blood. 2000;95:3832-3839)
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Pei J, Tan X, Chen K, Li X. [Design and optimization of a centrifugal pump for CPCR]. SHENG WU YI XUE GONG CHENG XUE ZA ZHI = JOURNAL OF BIOMEDICAL ENGINEERING = SHENGWU YIXUE GONGCHENGXUE ZAZHI 2000; 17:159-63. [PMID: 12557770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Requirements for an optimal centrifugal pump, the vital component in the equipment for cardiopulmonary cerebral resuscitation(CPCR), have been presented. The performance of the Sarns centrifugal pump (Sarns, Inc./3M, Ann arbor, MI, U.S.A) was tested. The preliminarily optimized model for CPCR was designed according to the requirements of CPCR and to the comparison and analysis of several clinically available centrifugal pumps. The preliminary tests using the centrifugal pump made in our laboratory(Type CPCR-I) have confirmed the design and the optimization.
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