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101.
Carl?Shooner Pierre-Luc?Caron Guylaine?Fréchette-Frigon Valérie?Leblanc Marie-Claude?Déry Eric?AsselinEmail author 《Reproductive biology and endocrinology : RB&E》2005,3(1):20
Background
During early rat pregnancy, trophoblast of the tiny embryo joins with the endometrium and epithelial cells undergo apoptosis. Near the end of pregnancy, regression of the decidua basalis (DB) is also observed (from day 14 to 20). However, little is known about the intra-cellular and molecular mechanisms involved in apoptosis regulation in the uterus during pregnancy. The objective of the present study was to investigate the presence and the developmental expression of transforming growth factor-beta isoforms (TGF-beta well known differentiation factor) in the rat endometrium throughout pregnancy and its action in vitro using cultured endometrial stromal cells. 相似文献102.
Cox CD Breslin MJ Mariano BJ Coleman PJ Buser CA Walsh ES Hamilton K Huber HE Kohl NE Torrent M Yan Y Kuo LC Hartman GD 《Bioorganic & medicinal chemistry letters》2005,15(8):2041-2045
Optimization of high-throughput screening (HTS) hits resulted in the discovery of 3,5-diaryl-4,5-dihydropyrazoles as potent and selective inhibitors of KSP. Dihydropyrazole 15 is a potent, cell-active KSP inhibitor that induces apoptosis and generates aberrant mitotic spindles in human ovarian carcinoma cells at low nanomolar concentrations. X-ray crystallographic evidence is presented which demonstrates that these inhibitors bind in an allosteric pocket of KSP distant from the nucleotide and microtubule binding sites. 相似文献
103.
Andreas Holbro Helen Baldomero Francesco Lanza Christian Chabannon John A. Snowden Andreas Buser Laura Infanti Nina Worel Anna Sureda Manuela Badoglio Jakob Passweg Chiara Bonini 《Cytotherapy》2018,20(3):453-460
Background
There is considerable heterogeneity in processing of stem cells for hematopoietic stem cell transplantation across Europe. The Foundation for the Accreditation of Cellular Therapy (FACT)–Joint Accreditation Committee International Society for Cellular Therapy and European Society for Blood and Marrow Transplantation (EBMT) (JACIE) standards provide minimum guidelines that, however, leave room for significant variations in practices at the individual transplantation center (TC).Methods
To better understand the extent of heterogeneity in storage conditions, quality controls (QCs), graft processing and disposal, a questionnaire was developed, reviewed by the Cellular Therapy and Immunobiology Working Party (CTIWP) and sent to all EBMT TCs.Results
In this study, 288 TCs from 46 countries (32 European, 14 associated) responded to the survey. Long-term storage is performed mainly either in liquid nitrogen or in the vapor phase of liquid nitrogen with 10% dimethyl sulfoxide (DMSO; 58% of centers). In case of microbiological contamination, most TCs make a case-by-case decision in collaboration with the clinicians. CD34+ counts are performed routinely either before and/or after thawing. Some centers perform additional QCs. DMSO is generally not removed (83%) and the graft is thawed at the bedside (68%) in a water bath (78%). There is heterogeneity between the centers regarding duration of storage and graft disposal.Discussion
Overall, this survey demonstrates that the majority of responding TCs uses standardized procedures (intracenter standardization). However, significant intercenter variations persist, which warrant further standardization and investigations on clinical and financial consequences. Additionally, efforts should be undertaken to provide more specific international guidelines on storage duration and graft disposal, which may also have an important impact on health care services worldwide. 相似文献104.
将化学合成的单链猪胰岛素前体(PIP)基因和用聚合酶链反应得到的α交配因子前导顺序(αMFL)基因插入质粒pVT102-U的醇脱氢酶基因ADH1的启动子和3’终止顺序之间而生成质粒pVT102-U/αMFL-PIP.被pVT102-U/αMFL-PIP转化的酵母(Saccharomyces cerevistae)可表达单链前体并分泌到培养基中.前体在纯化后可通过胰蛋白酶的转肽作用转变成人胰岛素.纯化的人胰岛素具有全部活力并可结晶.人胰岛素的总收率为每升培养液25mg. 相似文献
105.
The phylogenetic position of the Pedetidae, represented by a single species
Pedetes capensis, is controversial, reflecting in part the retention of
both Hystricomorphous and Sciurognathous characteristics in this rodent. In
an attempt to clarify the species evolutionary relationships, mtDNA gene
sequences from 10 rodent species (representing seven families) were
analyzed using phenetic, parsimony, and maximum-likelihood methods of
phylogenetic inference; the rabbit, Oryctolagus cuniculus (Order
Lagomorpha), and cow, Bos taurus (Order Artiodactyla), were used as
outgroups. Investigation of 714 base pairs of the protein-coding cytochrome
b gene indicate strong base bias at the third codon position with
significant rate heterogeneity evident between the three structural domains
of this gene. Similar analyses conducted on 816 base pairs of the 12S rRNA
gene revealed a transversion bias in the loop sections of all taxa. The
cytochrome b gene sequences proved useful in resolving associations between
closely related species but failed to produce consistent tree topologies at
the family level. In contrast, phylogenetic analysis of the 12S rRNA gene
resulted in strong support for the clustering of
Pedetidae/Heteromyidae/Geomyidae and Muridae in one clade to the exclusion
of the Hystricidae/Thryonomyidae and Sciuridae, a finding which is
concordant with studies of rodent fetal membranes as well as reproductive
and other anatomical features.
相似文献
106.
H Langen T Epprecht M Linden T Hehlgans B Gutte H R Buser 《European journal of biochemistry》1989,182(3):727-735
Heme compounds, in combination with a reducing agent and oxygen, can express various activities of cytochrome P-450 enzymes. In the present study it was found that a mixture of hemin and excess cysteine was able to degrade the insecticide DDT partially. The major products were three water-soluble, non-toxic conjugates of DDT metabolites with cysteine which had lost two or three of the five chlorine atoms of DDT per molecule and whose structures were elucidated by gas chromatography/mass spectrometry. In 0.05 M NH4HCO3, pH 7.7/ethanol (5:6, by vol.), the degradation reaction catalyzed by the hemin-cysteine model system was at least 8 x 10(4) times faster than the uncatalyzed reaction. In the presence of a designed 24-residues polypeptide or beta-casein, two DDT-binding proteins, an additional fourfold increase in the rate of DDT degradation was observed. Although the concentrations of DDT and cysteine occurring in an organism would be expected to be lower than those in the experiments described, the formation of water-soluble conjugates of DDT metabolites with cysteine (and other amino acids) could also play a role in metabolism and excretion of DDT in vivo. 相似文献
107.
Chanchal Sur Chowdhury Stavros Giaglis Ulrich A Walker Andreas Buser Sinuhe Hahn Paul Hasler 《Arthritis research & therapy》2014,16(3):R122
Introduction
Neutrophil extracellular traps (NETs) have recently been implicated in a number of autoimmune conditions, including rheumatoid arthritis (RA). We examined the underlying signaling pathways triggering enhanced NETosis in RA and ascertained whether the products of NETosis had diagnostic implications or usefulness.Methods
Neutrophils were isolated from RA patients with active disease and from controls. Spontaneous NET formation from RA and control neutrophils was assessed in vitro with microscopy and enzyme-linked immunosorbent assay (ELISA) for NETosis-derived products. The analysis of the signal-transduction cascade included reactive oxygen species (ROS) production, myeloperoxidase (MPO), neutrophil elastase (NE), peptidyl arginine deiminase 4 (PAD4), and citrullinated histone 3 (citH3). NET formation was studied in response to serum and synovial fluid and immunoglobulin G (IgG) depleted and reconstituted serum. Serum was analyzed for NETosis-derived products, for which receiver operator characteristic (ROC) curves were calculated.Results
Neutrophils from RA cases exhibited increased spontaneous NET formation in vitro, associated with elevated ROS production, enhanced NE and MPO expression, nuclear translocation of PAD4, PAD4-mediated citrullination of H3, and altered nuclear morphology. NET formation in both anti-citrullinated peptide antibody (ACPA)-positive and -negative RA was abolished by IgG depletion, but restored only with ACPA-positive IgG. NETosis-derived products in RA serum demonstrated diagnostic potential, the ROC area under the curve for cell-free nucleosomes being >97%, with a sensitivity of 91% and a specificity of 92%. No significant difference was observed between ACPA-positive and -negative cases.Conclusions
Signaling elements associated with the extrusion of NETs are significantly enhanced to promote NETosis in RA compared with healthy controls. NETosis depended on the presence of ACPA in ACPA-positive RA serum. The quantitation of NETosis-derived products, such as cell-free nucleosomes in serum, may be a useful complementary tool to discriminate between healthy controls and RA cases. 相似文献108.
JUAN ANTONIO DÍAZ‐PENDÓN M. CARMEN CAÑIZARES ENRIQUE MORIONES EDUARDO R. BEJARANO HENRYK CZOSNEK JESÚS NAVAS‐CASTILLO 《Molecular Plant Pathology》2010,11(4):441-450
Tomato yellow leaf curl disease (TYLCD) is one of the most devastating viral diseases affecting tomato crops in tropical, subtropical and temperate regions of the world. Here, we focus on the interactions through recombination between the different begomovirus species causing TYLCD, provide an overview of the interactions with the cellular genes involved in viral replication, and highlight recent progress on the relationships between these viruses and their vector, the whitefly Bemisia tabaci. Taxonomy: The tomato yellow leaf curl virus‐like viruses (TYLCVs) are a complex of begomoviruses (family Geminiviridae, genus Begomovirus) including 10 accepted species: Tomato yellow leaf curl Axarquia virus (TYLCAxV), Tomato yellow leaf curl China virus (TYLCCNV), Tomato yellow leaf curl Guangdong virus (TYLCGuV), Tomato yellow leaf curl Indonesia virus (TYLCIDV), Tomato yellow leaf curl Kanchanaburi virus (TYLVKaV), Tomato yellow leaf curl Malaga virus (TYLCMalV), Tomato yellow leaf curl Mali virus (TYLCMLV), Tomato yellow leaf curl Sardinia virus (TYLCSV), Tomato yellow leaf curl Thailand virus (TYLCTHV), Tomato yellow leaf curl Vietnam virus (TYLCVNV) and Tomato yellow leaf curl virus(TYLCV). We follow the species demarcation criteria of the International Committee on Taxonomy of Viruses (ICTV), the most important of which is an 89% nucleotide identity threshold between full‐length DNA‐A component nucleotide sequences for begomovirus species. Strains of a species are defined by a 93% nucleotide identity threshold. Host range: The primary host of TYLCVs is tomato (Solanum lycopersicum), but they can also naturally infect other crops [common bean (Phaseolus vulgaris), sweet pepper (Capsicum annuum), chilli pepper (C. chinense) and tobacco (Nicotiana tabacum)], a number of ornamentals [petunia (Petunia×hybrida) and lisianthus (Eustoma grandiflora)], as well as common weeds (Solanum nigrum and Datura stramonium). TYLCVs also infect the experimental host Nicotiana benthamiana. Disease symptoms: Infected tomato plants are stunted or dwarfed, with leaflets rolled upwards and inwards; young leaves are slightly chlorotic; in recently infected plants, fruits might not be produced or, if produced, are small and unmarketable. In common bean, some TYLCVs produce the bean leaf crumple disease, with thickening, epinasty, crumpling, blade reduction and upward curling of leaves, as well as abnormal shoot proliferation and internode reduction; the very small leaves result in a bushy appearance. 相似文献
109.
Sharma P Raina V Kumari R Malhotra S Dogra C Kumari H Kohler HP Buser HR Holliger C Lal R 《Applied and environmental microbiology》2006,72(9):5720-5727
Incubation of resting cells of Sphingobium indicum B90A, Sphingobium japonicum UT26, and Sphingobium francense Sp+ showed that they were able to transform beta- and delta-hexachlorocyclohexane (beta- and delta-HCH, respectively), the most recalcitrant hexachlorocyclohexane isomers, to pentachlorocyclohexanols, but only resting cells of strain B90A could further transform the pentachlorocyclohexanol intermediates to the corresponding tetrachlorocyclohexanediols. Moreover, experiments with resting cells of Escherichia coli expressing the LinB proteins of strains B90A, UT26, and Sp+ indicated that LinB was responsible for these transformations. Purified LinB proteins from all three strains also effected the formation of the respective pentachlorocyclohexanols. Although the three LinB enzymes differ only marginally with respect to amino acid sequence, they showed interesting differences with respect to substrate specificity. When LinB from strain B90A was incubated with beta- and delta-HCH, the pentachlorocyclohexanol products were further transformed and eventually disappeared from the incubation mixtures. In contrast, the LinB proteins from strains UT26 and Sp+ could not catalyze transformation of the pentachlorocyclohexanols, and these products accumulated in the incubation mixture. A mutant of strain Sp+ lacking linA and linB did not degrade any of the HCH isomers, including beta-HCH, and complementation of this mutant by linB from strain B90A restored the ability to degrade beta- and delta-HCH. 相似文献
110.
Simon Brooker Archie CA Clements Peter J Hotez Simon I Hay Andrew J Tatem Donald AP Bundy Robert W Snow 《Malaria journal》2006,5(1):1-8