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21.
Olga G. Cordeiro Mélanie Chypre Nathalie Brouard Simon Rauber Farouk Alloush Monica Romera-Hernandez Cécile Bénézech Zhi Li Anita Eckly Mark C. Coles Antal Rot Hideo Yagita Catherine Léon Burkhard Ludewig Tom Cupedo Fran?ois Lanza Christopher G. Mueller 《PloS one》2016,11(3)
Microenvironment and activation signals likely imprint heterogeneity in the lymphatic endothelial cell (LEC) population. Particularly LECs of secondary lymphoid organs are exposed to different cell types and immune stimuli. However, our understanding of the nature of LEC activation signals and their cell source within the secondary lymphoid organ in the steady state remains incomplete. Here we show that integrin alpha 2b (ITGA2b), known to be carried by platelets, megakaryocytes and hematopoietic progenitors, is expressed by a lymph node subset of LECs, residing in medullary, cortical and subcapsular sinuses. In the subcapsular sinus, the floor but not the ceiling layer expresses the integrin, being excluded from ACKR4+ LECs but overlapping with MAdCAM-1 expression. ITGA2b expression increases in response to immunization, raising the possibility that heterogeneous ITGA2b levels reflect variation in exposure to activation signals. We show that alterations of the level of receptor activator of NF-κB ligand (RANKL), by overexpression, neutralization or deletion from stromal marginal reticular cells, affected the proportion of ITGA2b+ LECs. Lymph node LECs but not peripheral LECs express RANK. In addition, we found that lymphotoxin-β receptor signaling likewise regulated the proportion of ITGA2b+ LECs. These findings demonstrate that stromal reticular cells activate LECs via RANKL and support the action of hematopoietic cell-derived lymphotoxin. 相似文献
22.
Erinaldo Ubirajara Damasceno dos Santos Géssica Dayane Cordeiro de Lima Micheline de Lucena Oliveira Sandra de Andrade Heráclio Hildson Dornelas Angelo da Silva Sergio Crovella Maria de Mascena Diniz Maia Paulo Roberto Eleutério de Souza/ 《Memórias do Instituto Oswaldo Cruz》2016,111(3):174-180
Polymorphisms in chemokine receptors play an important role in the progression of
cervical intraepithelial neoplasia (CIN) to cervical cancer (CC). Our study examined
the association of CCR2-64I (rs1799864) andCCR5-Δ32
(rs333) polymorphisms with susceptibility to develop cervical lesion (CIN and CC) in
a Brazilian population. The genotyping of 139 women with cervical lesions and 151
women without cervical lesions for the CCR2-64I and
CCR5-Δ32 polymorphisms were performed using polymerase chain
reaction-restriction fragment length polymorphism. The individuals carrying
heterozygous or homozygous genotypes (GA+AA) for CCR2-64I
polymorphisms seem to be at lower risk for cervical lesion [odds ratio (OR) = 0.37, p
= 0.0008)]. The same was observed for the A allele (OR = 0.39, p = 0.0002), while no
association was detected (p > 0.05) with CCR5-Δ32 polymorphism.
Regarding the human papillomavirus (HPV) type, patients carrying the
CCR2-64Ipolymorphism were protected against infection by HPV type
16 (OR = 0.35, p = 0.0184). In summary, our study showed a protective effect
ofCCR2-64I rs1799864 polymorphism against the development of
cervical lesions (CIN and CC) and in the susceptibility of HPV 16 infection. 相似文献
23.
24.
Evaluation of bone height in osseous free flap mandible reconstruction: an indirect measure of bone mass 总被引:8,自引:0,他引:8
Disa JJ Hidalgo DA Cordeiro PG Winters RM Thaler H 《Plastic and reconstructive surgery》1999,103(5):1371-1377
Osseous free flaps have become the preferred method of mandibular reconstruction after oncologic surgical ablation. To elucidate the long-term effects of free flap mandibular reconstruction on bone mass, maintenance or reduction in bone height over time was used as an indirect measure of preservation or loss in bone mass. Factors potentially influencing bone mass preservation were evaluated; these included site of reconstruction (central, body, ramus), patient age, length of follow-up, adjuvant radiotherapy, and the delayed placement of osseointegrated dental implants. A retrospective analysis of patients undergoing osseous free flap mandible reconstruction for oncologic surgical defects between 1987 and 1995 was performed. Postoperative Panorex examinations were used to evaluate bone height and bony union after osteotomy. Fixation hardware was used as a reference to eliminate magnification as a possible source of error in measurement. There were 48 patients who qualified for this study by having at least 24 months of follow-up. There were 27 male and 21 female patients, with a mean age of 45 years (range, 5 to 75 years). Mandibular defects were anterior (24) and lateral (24). Osseous donor sites included the fibula (35), radius (6), scapula (4), and ilium (3). There were between zero and four segmental osteotomies per patient (excluding the ends of the graft). Nineteen percent of all patients had delayed placement of osseointegrated dental implants. Initial Panorex examinations were taken between 1 and 9 months postoperatively (mean, 2 months). Follow-up Panorex examinations were taken 24 to 104 months postoperatively (mean, 47 months). The bony union rate after osteotomy was 97 percent. Bone height measurements were compared by site and type of reconstruction. The mean loss in fibula height by site of reconstruction was 2 percent in central segments, 7 percent in body segments, and 5 percent in ramus segments. The mean loss in bone height after radial free flap mandible reconstruction was 33 percent in central segments and 37 percent in body segments; ramus segments did not lose height. The central and body segments reconstructed with scapular free flaps did not lose height, but one ramus segment lost 20 percent of height. There was no loss in bone height in mandibular body reconstruction with the ilium free flap. Fibula free flaps did not significantly lose bone height when evaluated with respect to age, follow-up, radiation therapy, or dental implant placement. The retention in bone height demonstrated in this study suggests that bone mass is preserved after osseous free flap mandible reconstruction. The greatest amount of bone loss was seen after multiply osteotomized radial free flaps were used for central mandibular reconstruction. The ability of the fibula free flap to maintain mass over time, coupled with its known advantages, further supports its use as the "work horse" donor site for mandible reconstruction. 相似文献
25.
For a better understanding of virus x host interactions, transmission electron microscopy was used to characterize the intrahaemocoelic infection of Anticarsia gemmatalis larval haemocytes by A. gemmatalis M nucleopolyhedrovirus (AgMNPV). At 12 h post-infection (h p.i.), we observed nuclear hypertrophy, budded virus assembling, and protrusion towards the cytoplasm, virion envelopment, and accumulation of fibrillar aggregates in the cytoplasm. Around 24 h p.i., fibrillar aggregates also appeared inside nuclei of infected cells. By 48 h p.i., virogenic stroma and polyhedra were visualised in nuclei and at 72 h p.i., widespread infection in haemocytes was observed. Cell remnants and free polyhedra were phagocytosed by granular haemocyte 1 and plasmatocytes. Entire cells were phagocytosed only by plasmatocytes. Necrosis of infected cells was quite common, suggesting a putative cytotoxic response. Granular haemocyte 1 presented a more exuberant protrusion of budded viruses in comparison to other haemocytes. All types of haemocytes were shown to be infected, and the intense virus replication in some of these cells reveals the importance of haemolymph for AgMNPV spread in its natural host, a critical factor for permissiveness. 相似文献
26.
Background
Structural genomics (SG) projects aim to determine thousands of protein structures by the development of high-throughput techniques for all steps of the experimental structure determination pipeline. Crucial to the success of such endeavours is the careful tracking and archiving of experimental and external data on protein targets. 相似文献27.
28.
Fiuza SM Gomes C Teixeira LJ Girão da Cruz MT Cordeiro MN Milhazes N Borges F Marques MP 《Bioorganic & medicinal chemistry》2004,12(13):3581-3589
The antiproliferative and cytotoxic properties of polyphenolic acid derivatives, structurally related with the natural models caffeic and gallic acids, have been tested in human cervix adenocarcinoma cells (HeLa). Simultaneous structural information was obtained for these compounds through theoretical ab initio methods. This study was conducted for the following esters: methyl caffeate (MC, 1), propyl caffeate (PC, 2), octyl caffeate (OC, 3), methyl gallate (MG, 4), propyl gallate (PG, 5) and octyl gallate (OG, 6). A significant growth-inhibition effect was assessed for some of these compounds, clearly dependent on their structural characteristics. Marked structure-activity relationships (SARs)--namely the number of hydroxyl ring substituents--were found to rule the biological effect of such systems. 相似文献
29.
30.
Cordeiro AT Godoi PH Silva CH Garratt RC Oliva G Thiemann OH 《Biochimica et biophysica acta》2003,1645(2):117-122
The second enzyme in the glycolytic pathway, phosphoglucose isomerase (PGI), catalyses an intracellular aldose-ketose isomerization. Here we describe the human recombinant PGI structure (hPGI) solved in the absence of active site ligands. Crystals isomorphous to those previously reported were used to collect a 94% complete data set to a limiting resolution of 2.1 A. From the comparison between the free active site hPGI structure and the available human and rabbit PGI (rPGI) structures, a mechanism for protein initial catalytic steps is proposed. Binding of the phosphate moiety of the substrate to two distinct elements of the active site is responsible for driving a series of structural changes resulting in the polarisation of the active site histidine, priming it for the initial ring-opening step of catalysis. 相似文献