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101.
Boulos Zacharie Daniel Fortin Nicole Wilb Jean-François Bienvenu Michel Asselin Brigitte Grouix Christopher Penney 《Bioorganic & medicinal chemistry letters》2009,19(1):242-246
A series of 9-substituted and 2,9-disubstituted 6-(3-aminophenylamino) purines were synthesized and evaluated for their ability to mimic protein A binding to human IgG antibody. The structure–activity relationship (SAR) demonstrates that the 6-(3-aminoanilinyl) purine component was essential for activity. Purine 14 demonstrated significant activity, compared to protein A. These compounds may prove useful for the treatment of autoimmune diseases. 相似文献
102.
103.
Yawovi Zikpi Amoudji Guillaume Guinot Lionel Hautier Koffi Evenyon Kassegne Nils Chabrol Anne-Lise Charruault Ampah Kodjo C. Johnson Raphaël Sarr Pauline Yawoa D. Da Costa Jeremy E. Martin 《Annales de Paléontologie》2021,107(2):102472
Following our fieldwork in Paleogene deposits of Togo, we herein report cranial as well as postcranial elements belonging to the family Dyrosauridae. This assemblage is dated to the Late Paleocene (Thanetian) from two quarries in southern Togo. The specimens include a partial skull presenting two large supratemporal fossae and a massive occipital condyle; long and slender isolated teeth; amphicoelous vertebrae including several articulated ones; and two osteoderms devoid of carina. The morphology of the partial skull reveals similarities with some African longirostrine forms such as Rhabdognathus spp., although this attribution cannot be confirmed. Longirostrine forms, known in the late Paleocene and early Eocene of the Iullemmeden basin (Nigeria, Niger, Mali, Algeria) and in the phosphates of Morocco and Tunisia, is only represented in Thanetian levels in Togo. Different palaeoenvironmental settings seem to have characterized the various African basins during the lower Eocene, with consequences for the geographic distribution of dyrosaurids. These dyrosaurid remains confirm the presence of the family in Togo during the Paleocene and underline the fossiliferous potential of the coastal sedimentary basin in Togo and in the bay of Benin. 相似文献
104.
Alam M Beevers RE Ceska T Davenport RJ Dickson KM Fortunato M Gowers L Haughan AF James LA Jones MW Kinsella N Lowe C Meissner JW Nicolas AL Perry BG Phillips DJ Pitt WR Platt A Ratcliffe AJ Sharpe A Tait LJ 《Bioorganic & medicinal chemistry letters》2007,17(12):3463-3467
The development of a series of novel aminopyrimidines as inhibitors of c-Jun N-terminal kinases is described. The synthesis, in vitro inhibitory values for JNK1, JNK2 and CDK2, and the in vitro inhibitory value for a c-Jun cellular assay are discussed. 相似文献
105.
Water extract of Leonotis leonurus was tested for anticonvulsant activity against seizures produced in mice by pentylenetetrazole, picrotoxin, bicuculline and N-methyl-DL-aspartic acid (intraperitoneal injections). L. leonurus extract in the doses of 200 and 400 mg/kg respectively protected 37.5% and 50% of animals used and significantly (p < 0.05; Student's t-test) delayed pentylenetetrazole (90 mg/kg)-induced tonic seizures. Similarly, the same doses of L. leonurus extract significantly (p < 0.05; Student's t-test) delayed the onset of tonic seizures produced by picrotoxin (8 mg/kg) and N-methyl-DL-aspartic acid (400 mg/kg). However, all the doses of aqueous extract of L leonurus used did not alter the seizures induced by bicuculline (20 mg/kg) to any significant extent. The data suggest that the extract of L. leonurus has anticonvulsant activity and may probably be acting through non-specific mechanisms, since it affects both gabaergic and glutaminergic systems. High performance liquid chromatography (HPLC) and phytochemical tests carried out respectively show a spectrum profile, characteristic of L. leonurus and the presence of alkaloids, saponins and tannins in the extract. 相似文献
106.
Laurent Marsollier Raymond Robert Jacques Aubry Jean-Paul Saint Andr Henri Kouakou Pierre Legras Anne-Lise Manceau Chetaou Mahaza Bernard Carbonnelle 《Applied microbiology》2002,68(9):4623-4628
Mycobacterium ulcerans is an emerging environmental pathogen which causes chronic skin ulcers (i.e., Buruli ulcer) in otherwise healthy humans living in tropical countries, particularly those in Africa. In spite of epidemiological and PCR data linking M. ulcerans to water, the mode of transmission of this organism remains elusive. To determine the role of aquatic insects in the transmission of M. ulcerans, we have set up an experimental model with aquariums that mimic aquatic microenvironments. We report that M. ulcerans may be transmitted to laboratory mice by the bite of aquatic bugs (Naucoridae) that are infected with this organism. In addition, M. ulcerans appears to be localized exclusively within salivary glands of these insects, where it can both survive and multiply without causing any observable damage in the insect tissues. Subsequently, we isolated M. ulcerans from wild aquatic insects collected from a zone in the Daloa region of Ivory Coast where Buruli ulcer is endemic. Taken together, these results point to aquatic insects as a possible vector of M. ulcerans. 相似文献
107.
108.
Reduction in the DAZ gene copy number in two infertile men with impaired spermatogenesis. 总被引:3,自引:0,他引:3
Microdeletions of Yq are associated with azoospermia and severe oligozoospermia. Recently, we described a new molecular genetic strategy based on the denaturing gradient gel electrophoresis (DGGE) to rapidly identify deletions of the Y chromosome that include the DAZ locus. Using this approach, we have shown not a complete deletion but only a reduction in the number of copies of the DAZ gene by PCR-DGGE in two oligozoospermic patients. These results have been confirmed by Southern blot analysis. This finding suggests that partial deletion of the DAZ cluster could be cause of impaired spermatogenesis. 相似文献
109.
Because of the small size of their genome, viral genes have been forerunners in helping us understand gene expression. It is also because of their small size that viruses have elaborated the amazing variety of strategies that enables them to produce all the proteins they require for their multiplication. As a consequence, many of the strategies of expression known to occur in cell systems were first demonstrated in viruses. The aim of this review is to highlight the contribution of viruses to our knowledge of cell processes. 相似文献
110.
François Orange Samuel Dupont Olivier Le Goff Nadege Bienvenu Jean-Robert Disnar Frances Westall 《Geomicrobiology journal》2014,31(7):578-589
Recent experiments to fossilize microorganisms using silica have shown that the fossilization process is far more complex than originally thought; microorganisms not only play an active role in silica precipitation but may also remain alive while silica is precipitating on their cell wall. To better understand the mechanisms that lead to the preservation of fossilized microbes in recent and ancient rocks, we experimentally silicified a Gram-positive bacterium, Geobacillus SP7A, over a period of five years. The microbial response to experimental fossilization was monitored with the use of LIVE/DEAD staining to assess the structural integrity of the cells during fossilization. It documented the crucial role of silicification on the preservation of the cells and of their structural integrity after several years. Electron microscopy observations showed that initial fossilization of Gram-positive bacteria was extremely rapid, thus allowing very good preservation of Geobacillus SP7A cells. A thick layer of silica was deposited on the outer surface of cell walls in the earliest phase of silicification before invading the cytoplasmic space. Eventually, the cell wall was the only recognizable feature. Heavily mineralized cells thus showed morphological similarities with natural microfossils found in the rock record. 相似文献