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11.
12.
The immunoprotective Anaplasma marginale major surface protein 2 is encoded by a polymorphic multigene family. 总被引:5,自引:1,他引:5
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An Anaplasma marginale Florida msp-2 gene was cloned and expressed in Escherichia coli. Pulsed-field gel electrophoresis and Southern blot analysis revealed the presence of multiple msp-2 gene copies that were widely distributed throughout the chromosomes of all three strains examined. Genomic polymorphism among copies was greatest in the 5' end of msp-2 but also occurred in 3' regions. The presence of gene-copy-specific epitopes was indicated by the reactivity of the cloned msp-2 copy with some, but not all, monoclonal antibodies that bound native MSP-2. Multiple antigenically distinct MSP-2 molecules were expressed within strains and were coexpressed by individual A. marginale organisms. These results suggest that expression of polymorphic msp-2 gene copies is responsible for the significant percentages of A. marginale organisms within strains that do not react with individual anti-MSP-2 monoclonal antibodies. Sequence analysis revealed highly significant MSP-2 homology with two rickettsial surface proteins, A. marginale MSP-4 and Cowdria ruminantium MAP-1. Immunization with MSP-4 has been shown to induce protective immunity in a manner similar to that of immunization with MSP-2. These findings support the hypothesis that A. marginale surface proteins are targets of protective immune responses but are antigenically polymorphic. 相似文献
13.
Colland F Jacq X Trouplin V Mougin C Groizeleau C Hamburger A Meil A Wojcik J Legrain P Gauthier JM 《Genome research》2004,14(7):1324-1332
Access to the human genome facilitates extensive functional proteomics studies. Here, we present an integrated approach combining large-scale protein interaction mapping, exploration of the interaction network, and cellular functional assays performed on newly identified proteins involved in a human signaling pathway. As a proof of principle, we studied the Smad signaling system, which is regulated by members of the transforming growth factor beta (TGFbeta) superfamily. We used two-hybrid screening to map Smad signaling protein-protein interactions and to establish a network of 755 interactions, involving 591 proteins, 179 of which were poorly or not annotated. The exploration of such complex interaction databases is improved by the use of PIMRider, a dedicated navigation tool accessible through the Web. The biological meaning of this network is illustrated by the presence of 18 known Smad-associated proteins. Functional assays performed in mammalian cells including siRNA knock-down experiments identified eight novel proteins involved in Smad signaling, thus validating this integrated functional proteomics approach. 相似文献
14.
Expression of Anaplasma marginale major surface protein 2 operon-associated proteins during mammalian and arthropod infection
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Löhr CV Brayton KA Shkap V Molad T Barbet AF Brown WC Palmer GH 《Infection and immunity》2002,70(11):6005-6012
The antigenically variant major surface protein 2 (MSP2) of Anaplasma marginale is expressed from a 3.5-kb operon that contains, in a 5'-to-3' direction, four open reading frames, opag3, opag2, opag1, and msp2. This operon structure was shown to be conserved among genotypically and phenotypically distinct A. marginale, A. ovis, and A. centrale strains. The individual OpAG amino acid sequences are highly conserved among A. marginale strains, with identities ranging from 95 to 99%. OpAG2 and OpAG3 were expressed by all examined A. marginale strains during the acute rickettsemia in the mammalian host and, like MSP2, localize to the bacterial surface. OpAG2 and OpAG3 were also expressed in an infected Ixodes scapularis tick cell line. In contrast, the same A. marginale strains expressed only OpAG2 in two different Dermacentor spp. during transmission feeding. OpAG1 expression was not detected in the infected mammalian host, the infected tick cell line, or within infected Dermacentor ticks. The differential expression of outer membrane proteins from within an operon is a novel finding in tick-transmitted bacteria, and the regulation of expression may be broadly applicable to understanding how the pathogen adapts to the mammalian host-tick vector transition. 相似文献
15.
Christelle Faveeuw Marie-Claude Gagnerault Fran?oise Lepault 《Clinical & developmental immunology》1994,3(4):273-282
Subpopulations of lymphoid cells were compared with respect to their ability to migrate into
peripheral lymphoid organs of nonobese diabetic (NOD) mice and various strains of control
mice. In short-term, in vivo homing studies, no major differences in the pattern of homing
of B and T cells were observed among all mouse strains studied. On the other hand, CD4
cells localized consistently more efficiently than CD8 cells in both PP and LN of adult NOD
and BALB/c mice, whereas both populations migrated roughly equivalently in LN of adult
DBA/2, CBA, and C57BL/6 mice. No age-dependent differences in the homing of CD4 and
CD8 cells were observed in BALB/c mice. On the contrary, in 2-week-old NOD mice, CD4
and CD8 cells migrated equally well. The preferential entry of CD4 cells in adult NOD and
BALB/c did not result from increased blood transit time of CD8 cells. On the other hand,
the preferential migration of CD8 cells was observed in the liver, whereas the two T-cell
subsets migrated equally well in the lungs. The differences in the homing characteristics of
CD4 and CD8 cells among NOD, BALB/c, and C57BL/6 mice were not related to
modifications in the level of expression of adhesion molecules such as MEL-14, LFA-1, and
Pgp-1. 相似文献
16.
Conclusion The opening of the anal canal appears to be the factor which initiated the differentiation of the sphincter apparatus.The internal sphincter m. of the anus is entirely composed of smooth muscle as distinct from the striated fibers of the m. puborectalis, and the external sphincter which is a mixture of smooth and striated fibers (of skeletal type). It develops in the terminal part of the internal circular layer of the rectal m., outside which are longitudinal fibers which descend early to form the external sphincter (beginning around the third month).This study shows that the internal sphincter is scarcely evident before 12 SA. Thus continence between 10 and 12 SA (after the closure of the anal membrane) is closely related to the other components of the sphincter apparatus. On the other hand, the internal sphincter has become well formed after 28 to 30 SA and then plays a direct role in maintaining continence. 相似文献
17.
Margaux Serey‐Gaut Marcello Scala Bruno Reversade Lyse Ruaud Christelle Cabrol Francesco Musacchia Annalaura Torella Andrea Accogli Nathalie Escande‐Beillard Jean Langlais Gianluca Piatelli Alessandro Consales Vincenzo Nigro Valeria Capra Lionel Van Maldergem 《American journal of medical genetics. Part A》2020,182(6):1466-1472
The clinical and radiological spectrum of spondylocostal dysostosis syndromes encompasses distinctive costo‐vertebral anomalies. RIPPLY2 biallelic pathogenic variants were described in two distinct cervical spine malformation syndromes: Klippel–Feil syndrome and posterior cervical spine malformation. RIPPLY2 is involved in the determination of rostro‐caudal polarity and somite patterning during development. To date, only four cases have been reported. The current report aims at further delineating the posterior malformation in three new patients. Three patients from two unrelated families underwent clinical and radiological examination through X‐ray, 3D computed tomography and brain magnetic resonance imaging. After informed consent was obtained, family‐based whole exome sequencing (WES) was performed. Complex vertebral segmentation defects in the cervico‐thoracic spine were observed in all patients. WES led to the identification of the homozygous splicing variant c.240‐4T>G in all subjects. This variant is predicted to result in aberrant splicing of Exon 4. The current report highlights a subtype of cervical spine malformation with major atlo‐axoidal malformation compromising spinal cord integrity. This distinctive mutation‐specific pattern of malformation differs from Klippel–Feil syndrome and broadens the current classification, defining a sub‐type of RIPPLY2‐related skeletal disorder. Of note, the phenotype of one patient overlaps with oculo‐auriculo‐vertebral spectrum disorder. 相似文献
18.
MA Mayoux-Benhamou JP Barbet F Bargy C Vallée M Revel 《Surgical and radiologic anatomy : SRA》1990,12(3):181-185
Summary Biomechanical models of the cervical spine require knowledge of the position, size and orientation of the individual muscles that act on the cervical spine. We have developed a technique to stereometrically measure anatomical specimens. The apparatus is composed of three graduated metallic rods, which slide along a fixed support. This method is accurate to map the anatomy of individual muscles and provides quantitative data on their lines of action. Results are obtained from one specimen. The computer processing of the collected data allows formulation of a three-dimensional model of the neck muscles in man.
Méthode d'étude anatomique quantitative des muscles de la nuqueEtude préliminaire
Résumé Pour élaborer un modèle biomécanique de la colonne cervicale, il faut connaître la position, la taille et l'orientation des différents muscles du cou. Nous avons mis au point une méthode de mesure stéréométrique sur des sujets anatomiques. L'appareil est composé de 3 axes métalliques gradués qui coulissent sur un support fixe. Cette technique permet une étude anatomique précise de chacun des muscles de la nuque, fournissant des données quantitatives sur les différents faisceaux ou lignes d'action. Les résultats sont obtenus sur un sujet. Leur traitement informatique permettra l'élaboration d'un modèle mathématique tridimensionnel des muscles du cou chez l'homme.相似文献
19.
J. Raymond N. Kalach M. Bergeret J. P. Barbet P. H. Benhamou D. Gendrel C. Dupont 《European journal of clinical microbiology & infectious diseases》1996,15(5):415-417
A serological test for the diagnosis ofHelicobacter pylori infection (Cobas Core Roche, IgG, 2nd Generation; Roche, France) was compared with the examination of biopsy samples (culture and histology) obtained after endoscopy in 115 children to assess its value. In 94 children (42 positive and 52 negative), results were concordant. In 10 children a positive serological test was associated with an absence ofHelicobacter pylori, while in 11 others a negative serological test was associated with a positive culture. Sensitivity of the test was 79.2% and specificity 83.9%. A relationship between IgG titers and age (r=0.31, p<0.05) was found. Serological tests could be useful for the diagnosis ofHelicobacter pylori infection, but a negative test result does not rule out infection, particularly in children under 10 years of age. 相似文献
20.
Sleep deprivation effects on growth factor expression in neonatal rats: a potential role for BDNF in the mediation of delta power 总被引:4,自引:0,他引:4
Hairston IS Peyron C Denning DP Ruby NF Flores J Sapolsky RM Heller HC O'Hara BF 《Journal of neurophysiology》2004,91(4):1586-1595
The sleeping brain differs from the waking brain in its electrophysiological and molecular properties, including the expression of growth factors and immediate early genes (IEG). Sleep architecture and homeostatic regulation of sleep in neonates is distinct from that of adults. Hence, the present study addressed the question whether the unique homeostatic response to sleep deprivation in neonates is reflected in mRNA expression of the IEG cFos, brain-derived nerve growth factor (BDNF), and basic fibroblast growth factor (FGF2) in the cortex. As sleep deprivation is stressful to developing rats, we also investigated whether the increased levels of corticosterone would affect the expression of growth factors in the hippocampus, known to be sensitive to glucocorticoid levels. At postnatal days 16, 20, and 24, rats were subjected to sleep deprivation, maternal separation without sleep deprivation, sleep deprivation with 2 h recovery sleep, or no intervention. mRNA expression was quantified in the cortex and hippocampus. cFos was increased after sleep deprivation and was similar to control level after 2 h recovery sleep irrespective of age or brain region. BDNF was increased by sleep deprivation in the cortex at P20 and P24 and only at P24 in the hippocampus. FGF2 increased during recovery sleep at all ages in both brain regions. We conclude that cortical BDNF expression reflects the onset of adult sleep-homeostatic response, whereas the profile of expression of both growth factors suggests a trophic effect of mild sleep deprivation. 相似文献