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51.
A second nonrandom translocation, der(16)t(1;16)(q21;q13), in Ewing sarcoma and peripheral neuroectodermal tumor 总被引:1,自引:0,他引:1
E C Douglass S T Rowe M Valentine D Parham W H Meyer E I Thompson 《Cytogenetics and cell genetics》1990,53(2-3):87-90
The majority of Ewing sarcomas and peripheral neuroectodermal tumors (PNET) that have been karyotyped contain a specific translocation, t(11;22)(q23;q11). We report here a second nonrandom translocation, der(16)t(1;16)(q21;q13), in 2 of 20 cases of Ewing sarcoma (seven previously unreported) and 2 of 7 cases of PNET (all previously unreported). All cases with this translocation also contained the t(11;22). Comparison of C-banding patterns in tumor and peripheral lymphocyte karyotypes in one case indicated that the likely breakpoints were 1q21 and 16q13. The presence of this translocation in cell lines will enable further investigation of the molecular events important in the pathogenesis of Ewing sarcoma and PNET. 相似文献
52.
Jill A. Hollenbach Aliya Saperstein Mark Albrecht Cynthia Vierra-Green Peter Parham Paul J. Norman Martin Maiers 《PloS one》2015,10(8)
We conducted a nationwide study comparing self-identification to genetic ancestry classifications in a large cohort (n = 1752) from the National Marrow Donor Program. We sought to determine how various measures of self-identification intersect with genetic ancestry, with the aim of improving matching algorithms for unrelated bone marrow transplant. Multiple dimensions of self-identification, including race/ethnicity and geographic ancestry were compared to classifications based on ancestry informative markers (AIMs), and the human leukocyte antigen (HLA) genes, which are required for transplant matching. Nearly 20% of responses were inconsistent between reporting race/ethnicity versus geographic ancestry. Despite strong concordance between AIMs and HLA, no measure of self-identification shows complete correspondence with genetic ancestry. In certain cases geographic ancestry reporting matches genetic ancestry not reflected in race/ethnicity identification, but in other cases geographic ancestries show little correspondence to genetic measures, with important differences by gender. However, when respondents assign ancestry to grandparents, we observe sub-groups of individuals with well- defined genetic ancestries, including important differences in HLA frequencies, with implications for transplant matching. While we advocate for tailored questioning to improve accuracy of ancestry ascertainment, collection of donor grandparents’ information will improve the chances of finding matches for many patients, particularly for mixed-ancestry individuals. 相似文献
53.
Zhihui Deng Jianxin Zhen Genelle F Harrison Guobin Zhang Rui Chen Ge Sun Qiong Yu Neda Nemat-Gorgani Lisbeth A Guethlein Liumei He Mingzhong Tang Xiaojiang Gao Siqi Cai William H Palmer Jonathan A Shortt Christopher R Gignoux Mary Carrington Hongyan Zou Peter Parham Wenxu Hong Paul J Norman 《Molecular biology and evolution》2021,38(6):2582
Human natural killer (NK) cells are essential for controlling infection, cancer, and fetal development. NK cell functions are modulated by interactions between polymorphic inhibitory killer cell immunoglobulin-like receptors (KIR) and polymorphic HLA-A, -B, and -C ligands expressed on tissue cells. All HLA-C alleles encode a KIR ligand and contribute to reproduction and immunity. In contrast, only some HLA-A and -B alleles encode KIR ligands and they focus on immunity. By high-resolution analysis of KIR and HLA-A, -B, and -C genes, we show that the Chinese Southern Han (CHS) are significantly enriched for interactions between inhibitory KIR and HLA-A and -B. This enrichment has had substantial input through population admixture with neighboring populations, who contributed HLA class I haplotypes expressing the KIR ligands B*46:01 and B*58:01, which subsequently rose to high frequency by natural selection. Consequently, over 80% of Southern Han HLA haplotypes encode more than one KIR ligand. Complementing the high number of KIR ligands, the CHS KIR locus combines a high frequency of genes expressing potent inhibitory KIR, with a low frequency of those expressing activating KIR. The Southern Han centromeric KIR region encodes strong, conserved, inhibitory HLA-C-specific receptors, and the telomeric region provides a high number and diversity of inhibitory HLA-A and -B-specific receptors. In all these characteristics, the CHS represent other East Asians, whose NK cell repertoires are thus enhanced in quantity, diversity, and effector strength, likely augmenting resistance to endemic viral infections. 相似文献
54.
Parham Taslimi Sabiya Osmanova İlhami Gulçin Sabira Sardarova Vagif Farzaliyev Afsun Sujayev Ruya Kaya Fatma Koc Sukru Beydemir Saleh H. Alwasel Omer Irfan Kufrevioglu 《Journal of biochemical and molecular toxicology》2017,31(9)
Compounds containing nitrogen and sulfur atoms can be widely used in various fields, including industry, medicine, biotechnology, and chemical technology. Among them, amides of acids and heterocyclic compounds have an important place. These amides and thiazolidine‐4‐ones showed good inhibitory action against butyrylcholinesterase (BChE), acetylcholinesterase (AChE), and human carbonic anhydrase isoforms. AChE exists at high concentrations in the brain and red blood cells. BChE is an important enzyme that is plentiful in the liver, and it is released into the blood in a soluble form. They were demonstrated to have effective inhibition profiles with Ki values of 23.76–102.75 nM against hCA I, 58.92–136.64 nM against hCA II, 1.40–12.86 nM against AChE, and 9.82–52.77 nM against BChE. On the other hand, acetazolamide showed Ki value of 482.63 ± 56.20 nM against hCA I, and 1019.60 ± 163.70 nM against hCA II. Additionally, Tacrine inhibited AChE and BChE, showing Ki values of 397.03 ± 31.66 and 210.21 ± 15.98 nM, respectively. 相似文献
55.
Masoud Ghiasian Forough Khamisabadi Nejat Kheiripour Manouchehr Karami Rasool Haddadi Ali Ghaleiha Babak Taghvaei Seyed Sajad Oliaie Mohammadjavad Salehi Pouria Samadi Akram Ranjbar 《Journal of biochemical and molecular toxicology》2019,33(12)
Multiple sclerosis (MS) is an autoimmune disease in which the immune system attacks the nerve cells, resulting in neurological disorders. Oxidative stress, free radicals, and neuritis have important roles in MS pathogenesis. Here, we aim to evaluate the effect of crocin on inflammatory markers, oxidative damage, and deoxyribonucleic acid (DNA) damage in the blood of patients with MS. A total of 40 patients were divided into two groups, drug and placebo‐treated groups, using random assignment. Participants of the intervention and control groups received two crocin capsules or placebo per day for 28 days, respectively. Findings revealed a significant decrease in the level of important pathogenic factors in MS, including lipid peroxidation, DNA damage, tumor necrosis factor‐alpha, and interleukin 17 as well as a significant increase in the total antioxidant capacity in the serum of patients treated with crocin compared with the placebo group. Our results suggest the beneficial and therapeutic effects of crocin in MS. 相似文献
56.
Uncoating protein (hsc70) binds a conformationally labile domain of clathrin light chain LCa to stimulate ATP hydrolysis 总被引:10,自引:0,他引:10
Uncoating of clathrin-coated vesicles is mediated by the heat shock cognate protein, hsc70, and requires clathrin light chains (LCa and LCb) and ATP hydrolysis. We demonstrate that purified light chains and synthetic peptides derived from their sequences bind hsc70 to stimulate ATP hydrolysis. LCa is more effective than LCb in stimulating hsc70 ATPase and in inhibiting clathrin uncoating by hsc70. These differences correlate with high sequence divergence in the proline- and glycine-rich region (residues 47-71) that forms the hsc70 binding site. For LCa, but not LCb, this region undergoes reversible conformational changes upon perturbation of the ionic strength or the calcium ion concentration. Our results show that LCa is more important for interactions with hsc70 than is LCb and suggest a model in which the LCa conformation regulates coated vesicle uncoating. 相似文献
57.
58.
Identification and characterization of two novel lymphocyte function-associated antigens, L24 and L25 总被引:12,自引:0,他引:12
C Clayberger A M Krensky B W McIntyre T D Koller P Parham F Brodsky D J Linn E L Evans 《Journal of immunology (Baltimore, Md. : 1950)》1987,138(5):1510-1514
We describe the function and cell distribution of two novel cell surface antigens, L24 and L25. These antigens are broadly distributed on human lymphocytes. Monoclonal antibodies specific for these molecules block lysis by Class I- and II-specific cytotoxic T lymphocytes, but do not affect any other T cell functions tested. Anti-L24 antibody immunoprecipitates a molecule composed of two disulfide-linked monomers of 140 kd each. Anti-L25 antibody immunoprecipitates three proteins of 150, 85, and 75 kd. The study of these and other function associated molecules may provide insight into mechanisms of cytotoxic T lymphocyte recognition and/or function. 相似文献
59.
Janet H. Parham Marie A. Iannone Laurie K. Overton Jeff T. Hutchins 《Cytotechnology》1998,28(1-3):147-155
The goals of this study were to identify mammalian cell lines which could be efficiently transiently-transfected and scaled-up
for protein production. The transfection efficiencies of eight cell lines (NSO, NSO-TAg, CV-1, COS-7, CHO, CHO-TAg, HEK 293,
and 293-EBNA) were measured using electroporation for DNA delivery and green fluorescent protein (Evans, 1996) as the reporter
gene. In addition, we have evaluated the effects of stable expression of viral proteins, cell cycle manipulation, and butyrate
post-treatment in small scale experiments. The cell lines varied widely in their GFP transfection efficiencies. Stable expression
of simian virus 40 large T-antigen or Epstein Barr nuclear antigen failed to significantly increase transfection efficiency
above that seen in the parental lines. Aphidicolin (a DNA polymerase inhibitor), which blocked cells from S or G2/M, brought
about an increase in transfection efficiency in two cell lines. The primary effect of butyrate (a histone deacetylase inhibitor)
post-treatment was an increased intensity of the fluorescent signal of green fluorescent protein, as measured by flow cytometry
(1.0 to 4.2-fold, depending on the cell line). The combined use of aphidicolin pretreatment followed by butyrate treatment
post- electroporation yielded increases in fluorescence intensities ranging from 0.9 to 6.8-fold. Based on their high transfection
efficiencies in small scale experiments, rapid growth, and ability to grow in suspension culture, CHO, CHO-TAg, and 293-EBNA
were selected to assess the feasibility of using flow electroporation for large-scale transfections. Using secreted placental
alkaline phosphatase as a reporter, 293-EBNA cells produced the highest protein levels in both the presence and absence of
butyrate. These data indicate that flow electroporation provides an efficient method of DNA delivery into large numbers of
cells for mammalian protein production.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
60.
İlhami Gulçin Malahat Abbasova Parham Taslimi Zübeyir Huyut Leyla Safarova Afsun Sujayev 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):1174-1182
Compounds containing nitrogen and sulfur atoms can be widely used in various fields such as industry, medicine, biotechnology and chemical technology. Therefore, the reactions of aminomethylation and alkoxymethylation of mercaptobenzothiazole, mercaptobenzoxazole and 2-aminothiazole were developed. Additionally, the alkoxymethyl derivatives of mercaptobenzoxazole and 2-aminothiazole were synthesized by a reaction with hemiformals, which are prepared by the reaction of alcohols and formaldehyde. In this study, the inhibitory effects of these molecules were investigated against acetylcholinesterase (AChE), butyrylcholinesterase (BChE) enzymes and carbonic anhydrase I, and II isoenzymes (hCA I and II). Both hCA isoenzymes were significantly inhibited by the recently synthesized molecules, with Ki values in the range of 58–157?nM for hCA I, and 81–215?nM for hCA II. Additionally, the Ki parameters of these molecules for BChE and AChE were calculated in the ranges 23–88 and 18–78?nM, respectively. 相似文献