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41.
Albuquerque AS Cortesão CS Foxall RB Soares RS Victorino RM Sousa AE 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(5):3252-3259
IL-7 is a nonredundant cytokine for T cell homeostasis. Circulating IL-7 levels increase in lymphopenic clinical settings, including HIV-1 infection. HIV-2 infection is considered a "natural" model of attenuated HIV disease given its much slower rate of CD4 decline than HIV-1 and limited impact on the survival of the majority of infected adults. We compared untreated HIV-1- and HIV-2-infected patients and found that the HIV-2 cohort demonstrated a delayed increase in IL-7 levels during the progressive depletion of circulating CD4 T cells as well as a dissociation between the acquisition of markers of T cell effector differentiation and the loss of IL-7Ralpha expression. This comparison of two persistent infections associated with progressive CD4 depletion and immune activation demonstrates that a better prognosis is not necessarily associated with higher levels of IL-7. Moreover, the delayed increase in IL-7 coupled with sustained expression of IL-7Ralpha suggests a maximization of available resources in HIV-2. The observation that increased IL-7 levels early in HIV-1 infection were unable to reduce the rate of CD4 loss and the impaired expression of the IL-7Ralpha irrespective of the state of cell differentiation raises concerns regarding the use of IL-7 therapy in HIV-1 infection. 相似文献
42.
Machado RA Constantino L Martins MR de Albuquerque IM Menna-Barreto S Streck E Quevedo J Dal-Pizzol F 《Cell biology international》2007,31(9):1036-1041
Central nervous system dopaminergic mechanisms have been implicated in the cytokine response to stress and sepsis. We here describe the effects of haloperidol or clozapine in the treatment of sepsis induced by cecal ligation and puncture. Male Wistar rats were subjected to the CLP procedure were treated with haloperidol or clozapine and plasma cytokines, myeloperoxidase activity, markers of organ injury and survival was analyzed. The addition of haloperidol or clozapine to basic support did not diminished hepatic, renal, pancreatic or muscular damage observed after sepsis. Neither haloperidol, nor clozapine, modulates pro and antiinflammatory cytokines after sepsis induction. In addition, haloperidol treatment did not diminished myeloperoxidase activity in the kidney, lung or liver, or altered BALF markers of lung damage or inflammatory infiltration. Our data did not support a role of haloperidol or clozapine as an immunomodulator agent in the treatment of sepsis in an animal model of peritonitis. 相似文献
43.
El Ottra Juliana Hanna Leite de Albuquerque Melo-de-Pinna Gladys Flávia Demarco Diego Pirani José Rubens Ronse De Craene Louis P. 《Journal of plant research》2022,135(2):157-190
Journal of Plant Research - Sapindales is a monophyletic order within the malvid clade of rosids. It represents an interesting group to address questions on floral structure and evolution due to a... 相似文献
44.
Oliveira Willams Silva Jéssica Luiza S. Cruz-Neto Oswaldo Oliveira Marcela Tomaz P. Fernandes de Albuquerque Isabelle Borges Laís Angélica Lopes Ariadna Valentina 《Journal of plant research》2022,135(2):235-245
Journal of Plant Research - In mixed-ploidy populations, newly formed polyploids initially occur at low frequencies when compared to diploids. However, polyploidy may lead to morphological and... 相似文献
45.
Reinaldo de Menezes Martins Cristina de Albuquerque Possas Akira Homma 《Memórias do Instituto Oswaldo Cruz》2015,110(1):114-124
This paper presents, from the perspective of technological development and
production, the results of an investigation examining 61 clinical studies with
vaccines conducted in Brazil between 1938-2013, with the participation of the Oswaldo
Cruz Institute (IOC) and the Oswaldo Cruz Foundation (Fiocruz). These studies have
been identified and reviewed according to criteria, such as the kind of vaccine
(viral, bacterial, parasitic), their rationale, design and methodological strategies.
The results indicate that IOC and Fiocruz have accumulated along this time
significant knowledge and experience for the performance of studies in all clinical
phases and are prepared for the development of new vaccines products and processes.
We recommend national policy strategies to overcome existing regulatory and financing
constraints. 相似文献
46.
47.
Barros FW Bandeira PN Lima DJ Meira AS de Farias SS Albuquerque MR dos Santos HS Lemos TL de Morais MO Costa-Lotufo LV Pessoa Cdo Ó 《Bioorganic & medicinal chemistry》2011,19(3):1268-1276
Four derivatives of an α,β-amyrin mixture were synthesized by acylation with appropriate anhydrides. The structures of the compounds were confirmed by means of IR and (1)H and (13)C NMR. The compounds were screened for cytotoxic activity using four human tumor cell lines (HL-60, MDAMB-435, SF-295 and HCT-8) and normal peripheral blood mononuclear cells (PBMC). 3-O-Carboxymaleinate of α,β-amyrin (3a/3b) were found to be the only active compounds of the series (high cytotoxicity), showing IC(50) values ranging from 1.8 to 3μM. In PBMC, 3a/3b were not toxic, suggesting selectivity for tumor cells. To better understand the mechanism of action involved in the cytotoxicity of 3a/3b, HL-60 cells treated with 3a/3b were examined for morphological changes, DNA fragmentation, cell cycle perturbation, externalization of phosphatidylserine and activation of caspases 3/7, with doxorubicin serving as the positive control. The results indicate that the cytotoxicity of 3a/3b involves the induction of cell death by apoptosis. 相似文献
48.
49.
A remarkable aspect of the interaction of Cryptococcus neoformans with mammalian hosts is a consistent increase in capsule volume. Given that many aspects of the interaction of C. neoformans with macrophages are also observed with amoebae, we hypothesized that the capsule enlargement phenomenon also had a protozoan parallel. Incubation of C. neoformans with Acanthamoeba castellanii resulted in C. neoformans capsular enlargement. The phenomenon required contact between fungal and protozoan cells but did not require amoeba viability. Analysis of amoebae extracts showed that the likely stimuli for capsule enlargement were protozoan polar lipids. Extracts from macrophages and mammalian serum also triggered cryptococcal capsular enlargement. C. neoformans capsule enlargement required expression of fungal phospholipase B, but not phospholipase C. Purified phospholipids, in particular, phosphatidylcholine, and derived molecules triggered capsular enlargement with the subsequent formation of giant cells. These results implicate phospholipids as a trigger for both C. neoformans capsule enlargement in vivo and exopolysaccharide production. The observation that the incubation of C. neoformans with phospholipids led to the formation of giant cells provides the means to generate these enigmatic cells in vitro. Protozoan- or mammalian-derived polar lipids could represent a danger signal for C. neoformans that triggers capsular enlargement as a non-specific defense mechanism against potential predatory cells. Hence, phospholipids are the first host-derived molecules identified to trigger capsular enlargement. The parallels apparent in the capsular response of C. neoformans to both amoebae and macrophages provide additional support for the notion that certain aspects of cryptococcal virulence emerged as a consequence of environmental interactions with other microorganisms such as protists. 相似文献
50.
Three species that Navás described - Leucochrysa (Nodita) azevedoi Navás, 1913, Leucochrysa (Nodita) camposi (Navás, 1933) and Leucochrysa (Nodita) morenoi (Navás, 1934) - have received recent taxonomic attention. All three have many similar external features; indeed Navás himself, as well as subsequent authors, have confused the species with each other. Here, (a) misidentifications are corrected; (b) a neotype of Leucochrysa azevedoi is designated; (c) Leucochrysa (Nodita) morenoi, previously synonymized with Leucochrysa (Nodita) camposi, is recognized as a valid species [Reinstated status] All three species are redescribed and illustrated, with special emphasis on the types. Leucochrysa (Nodita) azevedoi was found to be relatively common in agricultural areas along Brazil's Atlantic coast. The two other species are known only from their type localities: Leucochrysa (Nodita) camposi - coastal Ecuador, and Leucochrysa (Nodita) morenoi - Quito, Ecuador. 相似文献