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71.
The Drosophila melanogaster proteins Flamingo and Prickle act in the planar cell polarity (PCP) pathway, which is required for acquisition of epithelial polarity in the wing, eye, and epidermis. In mammals, PCP signaling has been shown to regulate cell movements and polarity in a variety of tissues. Here, we show that the murine Flamingo orthologues Celsr1-3 and the Prickle orthologues Prickle1, Prickle2, and Testin have dynamic patterns of expression during pregastrulation and gastrulation stages. Celsr1 is expressed in the anterior visceral endoderm and nascent mesoderm, Celsr2 and Celsr3 mark the prospective neuroectoderm, Prickle1 is expressed in the primitive streak and mesoderm, Prickle2 in the node, and Testin in the anterior visceral endoderm, the extraembryonic ectoderm, primitive streak, and mesoderm. Analysis of a gene-trap mutation in Testin indicates that this gene is not required for embryogenesis; therefore, other Prickle homologues may compensate for its function during development. 相似文献
72.
Amlie Baron Juan Rodriguez‐Hernandez Eric Papon 《Macromolecular chemistry and physics.》2005,206(23):2381-2389
Summary: This study describes the chain extension, with polycaprolactone diols, of polyurethane‐graft‐poly(butyl acrylate)s which were first prepared by the step growth polymerization of a mixture of diphenylmethane‐4,4′‐diisocyanate (MDI) and α,α′‐dihydroxyl‐poly(butyl acrylate)s. The success of the chain extension reaction was studied and confirmed by 1H NMR, SEC and DSC analysis. The incorporation of polycaprolactone sequences in the polyurethane chains modified their specific adhesive properties, bringing cohesion to the material, as demonstrated by tack measurements.
73.
74.
Microtiter solid-phase radioimmunoassay for detection of Escherichia coli heat-labile enterotoxin. 总被引:8,自引:2,他引:8 下载免费PDF全文
H B Greenberg D A Sack W Rodriguez R B Sack R G Wyatt A R Kalica R L Horswood R M Chanock A Z Kapikian 《Infection and immunity》1977,17(3):541-545
The development of a microtiter solid-phase radioimmunoassay for the detection of Vibrio cholerae enterotoxin and heat-labile Escherichia coli enterotoxin is described. The test is based on the immunological similarity between V. cholerae toxin and E. coli heat-labile toxin. The assay is easy to perform, quantitative, and at least as sensitive and specific as the Y-1 adrenal cell system. 相似文献
75.
Lena Möbus Elke Rodriguez Inken Harder Agatha Schwarz Ulrike Wehkamp Dora Stölzl Nicole Boraczynski Sascha Gerdes Thomas Litman Andreas Kleinheinz Susanne Abraham Annice Heratizadeh Christiane Handrick Eva Haufe Jochen Schmitt Thomas Werfel Stephan Weidinger 《The Journal of allergy and clinical immunology》2021,147(5):1959-1965.e2
76.
Single-Step Multiplex PCR Assay for Characterization of New World Leishmania Complexes 总被引:2,自引:0,他引:2 下载免费PDF全文
Eva Harris Gerald Kropp Alejandro Belli Betzab Rodriguez Nina Agabian 《Journal of clinical microbiology》1998,36(7):1989-1995
We have developed a PCR assay for one-step differentiation of the three complexes of New World Leishmania (Leishmania braziliensis, Leishmania mexicana, and Leishmania donovani). This multiplex assay is targeted to the spliced leader RNA (mini-exon) gene repeats of these organisms and can detect all three complexes simultaneously, generating differently sized products for each complex. The assay is specific to the Leishmania genus and does not recognize related kinetoplastid protozoa, such as Trypanosoma cruzi, Trypanosoma brucei, and Crithidia fasciculata. It correctly identified Leishmania species with a broad geographic distribution in Central and South America. The sensitivity of the PCR amplification ranged from 1 fg to 10 pg of DNA (0.01 to 100 parasites), depending on the complex detected. Crude extracts of cultured parasites, prepared simply by boiling diluted cultures, served as excellent templates for amplification. Crude preparations of clinical material were also tested. The assay detected L. braziliensis in dermal scrapings from cutaneous leishmanial lesions, Leishmania chagasi in dermal scrapings of atypical cutaneous leishmaniasis, and L. mexicana from lesion aspirates from infected hamsters. We have minimized the material requirements and maximized the simplicity, rapidity, and informative content of this assay to render it suitable for use in laboratories in countries where leishmaniasis is endemic. This assay should be useful for rapid in-country identification of Leishmania parasites, particularly where different Leishmania complexes are found in the same geographical area. 相似文献
77.
An extracellular acetylcholinesterase produced by Aeromonas hydrophila is a major lethal toxin for fish 总被引:3,自引:0,他引:3
A hitherto unrecognised lethal toxin from the extracellular products (ECP) of Aeromonas hydrophila is described. The pure toxin was 300 times more toxic than the crude ECP and is the most toxic substance so far described from this bacterium, with a minimum lethal dose of 0.05 micrograms g-1 fish. The toxin had high acetylcholinesterase activity and occurred in native ECP as a monomeric 15.5 kDa polypeptide. The purified toxin had five isoelectric focusing forms ranging from pl 4.45 to 4.70. The ECP of each of six strains of A. hydrophila isolated from fish possessed acetylcholinesterase activity suggesting that the toxin is common in this species. The toxin was not a cytolysin and produced no gross pathology in injected fish. Its enzymic nature, low lethal dose, lack of tissue pathology and its apparent narcotic effect suggest that this toxin may act upon the central nervous system of the fish. 相似文献
78.
Virus persists in beta cells of islets of Langerhans and infection is associated with chemical manifestations of diabetes. II. Morphologic observations. 总被引:1,自引:1,他引:1 下载免费PDF全文
M. Rodriguez R. S. Garrett M. Raitt P. W. Lampert M. B. Oldstone 《The American journal of pathology》1985,121(3):497-504
Persistence of lymphocytic choriomeningitis (LCM) virus in the islets of Langerhans was associated with mild hyperglycemia and abnormal glucose tolerance test results. Early histopathologic events consisted of occasional perivascular inflammatory mononuclear cells around both islet and acinar cells. Morphometric studies showed an increase in the size of islets from virus-infected mice. By electron microscopy, LCM virions were found within infected beta cells. Cytolytic injury of beta cells was minimal and did not account for the abnormalities of glucose metabolism. In contrast to the findings in islets, ultrastructural studies of acinar cells revealed LCM virions in abundance, vacuolar degeneration, and intracytoplasmic inclusions. This study extends the previous observation that LCM virus infection may persist in beta cells of the islets of Langerhans without causing structural injury but be associated with abnormalities resembling the chemical and histopathologic features of the early stage of Type II (adult-onset) human diabetes mellitus. 相似文献
79.
L Vera-Cabrera M C Salinas-Carmona O Welsh M A Rodriguez 《Journal of clinical microbiology》1992,30(5):1183-1188
Two immunogenic proteins from a crude extract of Nocardia brasiliensis were purified to homogeneity. A 61-kDa protein (P61) was isolated from a 50% ammonium sulfate precipitate in two steps. Initially, P61 was obtained by electroelution in a 10% nondenatured preparative polyacrylamide gel electrophoresis (PAGE). In a second step, the eluate from the nondenatured gel was run in a 12% sodium dodecyl sulfate (SDS) preparative polyacrylamide gel. After elution, a single band was demonstrated by SDS-PAGE and Western blot (immunoblot). Also, a 24-kDa immunogenic protein (P24) was isolated by gel filtration in a Sephadex G-100 column and then by electroelution in a 12% nondenatured polyacrylamide gel. In a previous paper, we showed by Western blot assays that these proteins are recognized by the sera of mycetoma patients and not by sera from mycobacterial-infected or healthy individuals. We consider these proteins to be good candidates for the study of the host-parasite relationship in nocardial infections. The possible clinical application of these purified antigens in a serological diagnosis is discussed. 相似文献
80.
Microplate technique to determine hemolytic activity for routine typing of Listeria strains. 总被引:15,自引:2,他引:15 下载免费PDF全文
L Dominguez Rodriguez J A Vazquez Boland J F Fernandez Garayzabal P Echalecu Tranchant E Gomez-Lucia E F Rodriguez Ferri G Suarez Fernandez 《Journal of clinical microbiology》1986,24(1):99-103
Because the hemolysis produced by Listeria monocytogenes and Listeria seeligeri on blood agar is frequently difficult to interpret, we developed a microplate technique for the routine determination of hemolytic activity with erythrocyte suspensions. This microtechnique is a simple and reliable test for distinguishing clearly between hemolytic and nonhemolytic strains and could be used instead of the CAMP (Christie-Atkins-Munch-Petersen) test with Staphylococcus aureus in the routine typing of Listeria strains. Furthermore, our results suggest that the quantitation of the hemolytic activity of the Listeria strains, along with the D-xylose, L-rhamnose, and alpha-methyl-D-mannoside acidification tests, allows the differentiation of L. monocytogenes, L. seeligeri, and Listeria ivanovii. We also observed that the treatment of erythrocytes with crude exosubstances of rhodococcus equi, Pseudomonas fluorescens, Acinetobacter calcoaceticus, and S. aureus enhanced the hemolytic activity of all Listeria strains with this characteristic. 相似文献