952 resultados para Archives and Publication Cell


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Illegitimate V(D)J-recombination in lymphoid malignancies involves rearrangements in immunoglobulin or T-cell receptor genes, and these rearrangements may play a role in oncogenic events. High frequencies of TRGV-BJ hybrid gene (rearrangement between the TRB and TRG loci at 7q35 and 7p14-15, respectively) have been detected in lymphocytes from patients with ataxia telangiectasia (AT), and also in patients with lymphoid malignancies. Although the TRGV-BJ gene has been described only in T-lymphocytes, we previously detected the presence of TRGV-BJ hybrid gene in the genomic DNA extracted from SV40-transformed AT5BIVA fibroblasts from an AT patient. Aiming to determine whether the AT phenotype or the SV40 transformation could be responsible for the production of the hybrid gene by illegitimate V(D)J-recombination, DNA samples were extracted from primary and SV40-transformed (normal and AT) cell lines, following Nested-PCR with TRGV- and TRBJ-specific primers. The hybrid gene was only detected in SV40-transformed fibroblasts (AT-5BIVA and MRC-5). Sequence alignment of the cloned PCR products using the BLAST program confirmed that the fragments corresponded to the TRGV-BJ hybrid gene. The present results indicate that the rearrangement can be produced in nonlymphoid cells, probably as a consequence of the genomic instability caused by the SV40-transformation, and independently of ATM gene mutation.

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Resistance to drug is a major cause of treatment failure in pediatric brain cancer. The multidrug resistance (MDR) phenotype can be mediated by the superfamily of adenosine triphosphate-binding cassette (ABC) transporters. The dynamics of expression of the MDR genes after exposure to chemotherapy, especially the comparison between pediatric brain tumors of different histology, is poorly described. To compare the expression profiles of the multidrug resistance genes ABCB1, ABCC1, and ABCG2 in different neuroepithelial pediatric brain tumor cell lines prior and following short-term culture with vinblastine. Immortalized lineages from pilocytic astrocytoma (R286), anaplasic astrocytoma (UW467), glioblastoma (SF188), and medulloblastoma (UW3) were exposed to vinblastine sulphate at different schedules (10 and 60 nM for 24 and 72 h). Relative amounts of mRNA expression were analyzed by real-time quantitative polymerase chain reaction. Protein expression was assessed by immunohistochemistry for ABCB1, ABCC1, and ABCG2. mRNA expression of ABCB1 increased together with augmenting concentration and time of exposure to vinblastine for R286, UW467, and UW3 cell lines. Interestingly, ABCB1 levels of expression diminished in SF188. Following chemotherapy, mRNA expression of ABCC1 decreased in all cell lines other than glioblastoma. ABCG2 expression was influenced by vinblastine only for UW3. The mRNA levels showed consistent association to protein expression in the selected sets of cell lines analyzed. The pediatric glioblastoma cell line SF188 shows different pattern of expression of multidrug resistance genes when exposed to vinblastine. These preliminary findings may be useful in determining novel strategies of treatment for neuroepithelial pediatric brain tumors.

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Purpose: To investigate potential retinal neuroprotective effects of oral lamotrigine in rabbits after pars plana vitrectomy (PPV) and intravitreal silicone oil injection (SOI). Methods: Twelve New Zealand rabbits (weight, 2.0-2.5 kg) underwent PPV with SOI on the right eye. For 30 days postoperatively, 6 rabbits received a daily oral dose of lamotrigine (25 mg/kg), and 6 rabbits received a daily oral dose of water. The animals were killed 30 days after surgery. All retinas were processed histologically, immunostained using glial fibrillary acidic protein (GFAP), and analyzed by fluorescence microscopy. Retina sections from all groups were analyzed by TUNEL for the presence of apoptosis and stained with hematoxylin-eosin for morphologic analysis and retina cell density measurements in each layer using a Zeiss Axiophot microscope and KS 400 software. Results: Retinas from water-operated eyes showed a significant decrease in cell density associated with cell death compared with retinas from water-control eyes; cell density was reduced by 56% in the outer nuclear layer (ONL), 49% in the inner nuclear layer (INL), and 64% in the ganglion cell layer (GCL). Lamotrigine-operated retinas showed a reduction in cell death when compared with water-operated retinas; cell death was reduced by 52% in the ONL, 25% in the INL, and 56% in the GCL. Water-operated retinas showed TUNEL-positive cells and GFAP immunofluorescence throughout Muller cell processes; lamotrigine-operated retinas showed no TUNEL-positive cells and decreased GFAP staining when compared with water-operated retinas. Conclusions: PPV with SOI was associated with apoptosis of retinal cells and activation of glial cells in rabbit eyes. Oral lamotrigine administration provided protection against these effects.

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Background. The live attenuated yellow fever (YF) vaccines have been available for decades and are considered highly effective and one of the safest vaccines worldwide. Methods. The impact of YF-17DD-antigens recall on cytokine profiles of YF-17DD-vaccinated children were characterized using short-term cultures of whole blood samples and single-cell flow cytometry. This study enrolled seroconverters and nonseroconverters after primovaccination (PV-PRNT(+) and PV-PRNT(-)), seroconverters after revaccination (RV-PRNT(+)), and unvaccinated volunteers (UV-PRNT(-)). Results. The analysis demonstrated in the PV-PRNT(+) group a balanced involvement of pro-inflammatory/regulatory adaptive immunity with a prominent participation of innate immunity pro-inflammatory events (IL-12(+) and TNF-alpha(+) NEU and MON). Using the PV-PRNT(+) cytokine signature as a reference profile, PV-PRNT(+) presented a striking lack of innate immunity proinflammatory response along with an increased adaptive regulatory profile (IL-4(+) CD4(+) T cells and IL-10(+) and IL-5(+) CD8(+) T cells). Conversely, the RV-PRNT(+) shifted the overall cytokine signatures toward an innate immunity pro-inflammatory profile and restored the adaptive regulatory response. Conclusions. The data demonstrated that the overall cytokine signature was associated with the levels of PRNT antibodies with a balanced innate/adaptive immunity with proinflammatory/regulatory profile as the hallmark of PV-PRNT(MEDIUM+), whereas a polarized regulatory response was observed in PV-PRNT(-) and a prominent proinflammatory signature was the characteristic of PV-PRNT(HIGH+).

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A DNA vaccine expressing dengue-4 virus premembrane (prM) and envelope (E) genes was produced by inserting these genes into a mammalian expression plasmid (pCI). Following a thorough screening, including confirmation of protein expression in vitro, a recombinant clone expressing these genes was selected and used to immunize BALB/c mice. After 3 immunizations all the animals produced detectable levels of neutralizing antibodies against dengue-4 virus. The cytokines levels and T cell proliferation, detected ex vivo from the spleen of the immunized mice, showed that our construction induced substantial immune stimulation after three doses. Even though the antibody levels, induced by our DNA vaccine, were lower than those obtained in mice immunized with dengue-4 virus the levels of protection were high with this vaccine. This observation is further supported by the fact that 80% of the vaccine immunized group was protected against lethal challenge. In conclusion, we developed a DNA vaccine employing the genes of the prM and E proteins from dengue-4 virus that protects mice against this virus. (C) 2010 Elsevier Ltd. All rights reserved.

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Large, long-lived species experience more lifetime cell divisions and hence a greater risk of spontaneous tumor formation than smaller, short-lived species. Large, long-lived species are thus expected to evolve more elaborate tumor suppressor systems. In previous work, we showed that telomerase activity coevolves with body mass, but not lifespan, in rodents: telomerase activity is repressed in the somatic tissues of large rodent species but remains active in small ones. Without telomerase activity, the telomeres of replicating cells become progressively shorter until, at some critical length, cells stop dividing. Our findings therefore suggested that repression of telomerase activity mitigates the increased risk of cancer in larger-bodied species but not necessarily longer-lived ones. These findings imply that other tumor suppressor mechanisms must mitigate increased cancer risk in long-lived species. Here, we examined the proliferation of fibroblasts from 15 rodent species with diverse body sizes and lifespans. We show that, consistent with repressed telomerase activity, fibroblasts from large rodents undergo replicative senescence accompanied by telomere shortening and overexpression of p16(Ink4a) and p21(Cip1/Waf1) cycline-dependent kinase inhibitors. Interestingly, small rodents with different lifespans show a striking difference: cells from small shorter-lived species display continuous rapid proliferation, whereas cells from small long-lived species display continuous slow proliferation. We hypothesize that cells of small long-lived rodents, lacking replicative senescence, have evolved alternative tumor-suppressor mechanisms that prevent inappropriate cell division in vivo and slow cell growth in vitro. Thus, large-bodied species and small but long-lived species have evolved distinct tumor suppressor mechanisms.

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The objective was to evaluate the effect of beta-lactoglobulin (beta-lg) polymorphism and seasonality on milk composition (fat, lactose, total solids, milk urea nitrogen, total protein, true protein, casein and somatic cell counts) of Holstein and Girolando cows. Milk and blood samples from 278 Holsteins cows and 156 Girolando cows were taken during two dry seasons and two rainy seasons, for milk composition analysis and to determine beta-lg genotypes, respectively. BB genotype was the most frequent for both breeds, followed by AA genotype for Holstein (BB>AA>AB) and by AB for Girolando cows (BB>AB>AA). No differences were found in milk compositional characteristics among genetic variants of beta-lg (AA, AB and BB) either between Holstein or Girolando cows. No association between milk composition and beta-lg genetic polymorphism was observed. During the dry season, independently of the breed considered, higher contents of lactose, true protein, casein and casein :true protein ratio were found.

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The endocannabinoid system has become a topic of great interest in pharmacology due to its remarkable distribution in mammal organisms and capacity to play a modulatory role on several physiological systems, including modulation of immunity. Many studies have shown that administration of cannabinoids causes inhibitory effects on immune cells, including decreased proliferation and antigen-presenting cell (APC) costimulatory activity. In contrast, other groups have shown that some cannabinoids might present stimulatory actions on macrophage activity and T cell activation. Therefore, we aimed to investigate whether a treatment in vivo with a low dose of anandamide (0.1 mg/kg) immediately prior to sensitization would have an immunosuppressive or immunostimulatory effect on cell-mediated immunity (Th1 response) in mice. We report here that anandamide, prior to sensitization, was able to increase the Th1 response to ovalbumin in vivo and ex vivo. Anandamide increased delayed type hypersensitivity (DTH), splenocyte proliferation, and IFN-gamma production in a co-culture of adherent and non-adherent splenocytes. Moreover, anandamide prior to sensitization increased both the expression of DC co-stimulatory molecules (CD80/CD86) and IL-12/IL23 (p40) production ex vivo. We have also assessed direct effects of anandamide in the IFN-gamma/IL-4 balance of ConA-stimulated splenocytes in vitro. Anandamide at nanomolar concentrations increased the production of IFN-gamma, while such production decreased at micromolar range. Thus, anandamide induced both the increment of DC activation and IFN-gamma production, which are likely the mechanisms involved in the increase of Th1 response reported here. (C) 2010 Elsevier B.V. All rights reserved.

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Increased amounts of reactive oxygen species (ROS) during in vitro fertilization (IVF) may cause cytotoxic damage to gametes, whereas small amounts of ROS favour sperm capacitation. The aim of this study was to investigate the effect of antioxidants [50 mu M beta-mercaptoethanol (beta-ME) and 50 mu M cysteamine (Cyst)] or a pro-oxidant (5 mm buthionine sulfoximine) on the quality and penetrability of spermatozoa into bovine oocytes and on the subsequent embryo development and quality when added during IVF. Sperm quality, evaluated by the integrity of plasma and acrosomal membranes, and mitochondrial function, was diminished (p < 0.05) after 4-h culture in the presence of antioxidants. Oocyte penetration rates were similar between treatments (p > 0.05), but antioxidants adversely affected the normal pronuclear formation rates (p < 0.05). The incidence of polyspermy was high for beta-ME (p < 0.05). No differences were observed in cleavage rates between treatments (p > 0.05). However, the developmental rate to the blastocyst stage was adversely affected by Cyst treatment (p < 0.05). The quality of embryos that reached the blastocyst stage, evaluated by total, inner cell mass (ICM) and trophectoderm cell numbers and ICM/total cell ratio was unaffected (p > 0.05) by treatments. The results indicate that ROS play a role in the fertilizing capacity in bovine spermatozoa, as well as in the interaction between the spermatozoa and the oocytes. It can be concluded that supplementation with antioxidants during IVF procedures impairs sperm quality, normal pronuclear formation and embryo development to the blastocyst stage.

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The continuum of folliculogenesis begins in the fetal ovary with the differentiation of the oogonia and their isolation within the primordial follicles. Primordial follicle activation is an enigmatic process, whereby some follicles enter the growing pool to become primary follicles, thereby embarking on an irreversible progression towards ovulation or atresia. This process is under the coordinated regulation of factors from the oocyte itself, as well as from the somatic cells of the ovary, in particular the theca and granulosa cells, which are structural components of the follicle. These two influences provide the principal stimuli for the growth of the follicle to the late preantral or early antral stage of development. The endocrine effects of the gonadotrophins FSH and LH are essential to the continued progression of the follicle and most atresia can be attributed to the failure to receive or process the gonadotrophin signals. The peri-ovulatory state has received intensive investigation recently, demonstrating a coordinated role for gonadotrophins, steroids, epidermal growth factor family proteins and prostaglandins. Thus, a complex programme of coordinated interaction of governing elements from both germ and somatic cell sources is required for successful follicle development.

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The vomeronasal system is crucial for social and sexual communication in mammals. Two populations of vomeronasal sensory neurons, each expressing G alpha i2 or G alpha o proteins, send projections to glomeruli of the rostral or caudal accessory olfactory bulb, rAOB and cAOB, respectively. In rodents, the G alpha i2- and G alpha o-expressing vomeronasal pathways have shown differential responses to small/volatile vs. large/non-volatile semiochemicals, respectively. Moreover, early gene expression suggests predominant activation of rAOB and cAOB neurons in sexual vs. aggressive contexts, respectively. We recently described the AOB of Octodon degus, a semiarid-inhabiting diurnal caviomorph. Their AOB has a cell indentation between subdomains and the rAOB is twice the size of the cAOB. Moreover, their AOB receives innervation from the lateral aspect, contrasting with the medial innervation of all other mammals examined to date. Aiming to relate AOB anatomy with lifestyle, we performed a morphometric study on the AOB of the capybara, a semiaquatic caviomorph whose lifestyle differs remarkably from that of O. degus. Capybaras mate in water and scent-mark their surroundings with oily deposits, mostly for male-male communication. We found that, similar to O. degus, the AOB of capybaras shows a lateral innervation of the vomeronasal nerve, a cell indentation between subdomains and heterogeneous subdomains, but in contrast to O. degus the caudal portion is larger than the rostral one. We also observed that four other caviomorph species present a lateral AOB innervation and a cell indentation between AOB subdomains, suggesting that those traits could represent apomorphies of the group. We propose that although some AOB traits may be phylogenetically conserved in caviomorphs, ecological specializations may play an important role in shaping the AOB.

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Aims: Granular cell tumor (GCT) is a rare neoplasm that can appear in any site of the body, but most are located intraorally. Its histogenetic origin remains unclear. This report analyzes the immunoprofile of 15 cases of granular cell tumors, occurring in 13 women and 2 men and the lesions were located on the tongue or upper lip. Patient age ranged from 7 to 52. Methods: The patients demographic data and the cytological and architectural features of the lesions were analyzed in oral GCTs (n = 15). The lesions were also submitted to a panel of immunohistochemical stains with antibodies against S-100, p75, NSE, CD-68, Ki-67, Synaptofisin, HHF-35, SMA, EMA, Chromogranin, Progesterone, Androgen and Estrogen. Results: Among the fifteen cases analyzed, the most common location was the tongue (84.6%). Histologically, the tumors exhibited cellular proliferation composed mainly by polygonal cells presenting an abundant granular eosinophilic cytoplasm. The nuclei were central, and the cell membranes were moderately clear. No mitotic figures were observed. The immunohistochemical analysis showed positivity in all cases for S-100, p75, NSE and CD-68, and no immunoreactivity for Ki-67, Synaptofisin, HHF-35, SMA, EMA, Chromogranin, Progesterone, Androgen and Estrogen. Conclusion: The immunoprofile of granular cell tumors showed nerve sheath differentiation - lending support to their neural origin - and helping to establish a differential diagnosis between this lesion and other oral granular cell tumors, whether benign or malignant.

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Clear cell odontogenic carcinoma (CCOC) is a rare odontogenic tumor associated with aggressive clinical behavior, metastasis, and low survival. We report a case of CCOC affecting the mandible of a 39-year-old man. The tumor presented a biphasic pattern composed of clear cell nests intermingled with eosinophilic cells and separated by collagenous stroma. Immunoreactivity to cytokeratin (CK), specifically AE1/AE3 and CK 8, 14, 18, and 19 was found, as well as to epithelial membrane antigen (EMA). The tumor cells were negative for S100 protein, CK 13, vimentin, smooth muscle actin, laminin and type IV collagen. Low labeling indices for the proliferation markers Ki-67 and proliferating cell nuclear antigen and to p53 protein might predict a favorable prognosis for the lesion. A surgical resection was performed, followed by adjuvant radiotherapy. A 2-year follow-up has shown no signs of recurrence. The significance of histochemical and immunohistochemical resources in the correct diagnosis of CCOC is analyzed.

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Transforming growth factor-beta (TGF-beta) is a multifunctional growth factor that has several biological effects in vivo including control of cell growth and differentiation, cell migration, lineage determination, motility, adhesion, apoptosis, and synthesis and degradation of extracellular matrix, and TGF-beta plays an important role in regulating tissue repair and regeneration. Our study analyzed the participation of TGF-beta 1, -beta 2, and -beta 3 in the different stages of morphogenesis and differentiation of human developing dental organ using immunobistochemistry. The maxillae and mandibles of 10 human embryos ranging from 8 to 23 weeks of gestation were employed, according to the approval of the ethical committee. Our study revealed that the TGF-beta subunits-beta 1, beta 2, and beta 3 were present in the various stages of tooth development, but the expression varied according to the differentiation stage, tissue, and TGF-beta subunit. Our results indicated that TGF-beta 1 is closely related to differentiation of enamel organ and initiation of matrix secretion, TGF-beta 2 to cellular differentiation, and TGF-beta 3 to mineral maturation matrix.

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Cutaneous leishmaniasis (CL) includes different clinical manifestations displaying diverse intensities of dermal Inflammatory infiltrate Diffuse CL (DCL) cases are hyporesponsive and lesions show very few lymphocytes and a predominance of macrophages In contrast localized CL (LCL) cases are responsive to leishmanial antigen and lesions exhibit granulocytes and mononuclear cell infiltration in the early phases changing to a pattern with numerous lymphocytes and macrophages later in the lesion Therefore different chemokines may affect the predominance of cell infiltration in distinct clinical manifestations In lesions from LCL patients we examined by flow cytometry the presence of different chemokines and their receptors in T cells and we verified a higher expression of CXCR3 in the early stages of LCL (less than 30 days of infection) and a higher expression of CCR4 in the late stages of disease (more than 60 days of infection) We also observed a higher frequency of T cells producing IL-10 in the late stage of LCL Using immunohistochemistry we observed a higher expression of CCL7 CCL17 in lesions from late LCL as well as CCR4 suggesting a preferential recruitment of regulatory T cells in the late LCL Comparing lesions from LCL and DCL patients we observed a higher frequency of CCL7 in DCL lesions These results point out the Importance of the chemokines defining the different types of cells recruited to the site of the infection which could be related to the outcome of infection as well as the clinical form observed (C) 2010 American Society for Histocompatibility and Immunogenetics Published by Elsevier Inc All rights reserved