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Find video protocols related to scientific articles indexed in Pubmed.
Initiation codon selection is accomplished by a scanning mechanism without crucial initiation factors in Sindbis virus subgenomic mRNA.
RNA
PUBLISHED: 11-19-2014
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Translation initiation of alphavirus subgenomic mRNA (sgmRNA) can occur in the absence of several initiation factors (eIFs) in infected cells; however, the precise translation mechanism is still poorly understood. In this study, we have examined the mechanism of initiation and AUG selection in Sindbis virus (SINV) sgmRNA. Our present findings suggest that sgmRNA is translated via a scanning mechanism, since the presence of a hairpin structure before the initiation codon hampers protein synthesis directed by this mRNA. In addition, translation is partially recovered when an in-frame AUG codon is placed upstream of this hairpin. This scanning process takes place without the participation of eIF4A and active eIF2. These results, combined with our findings through modifying the SINV sgmRNA leader sequence, do not support the possibility of a direct initiation from the start codon without previous scanning, or a shunting mechanism. Moreover, studies carried out with sgmRNAs containing two alternative AUG codons within a good context for translation reveal differences in AUG selection which are dependent on the cellular context and the phosphorylation state of eIF2?. Thus, initiation at the additional AUG is strictly dependent on active eIF2, whereas the genuine AUG codon can start translation following eIF2? inactivation. Collectively, our results suggest that SINV sgmRNA is translated by a scanning mechanism without the potential participation of crucial eIFs. A model is presented that explains the mechanism of initiation of mRNAs bearing two alternative initiation codons.
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[Dental health: relationship between dental caries and food consumption].
Nutr Hosp
PUBLISHED: 07-10-2013
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Although the reduction and prevalence of dental caries in many countries has been largely associated with the use of fluorine and improving dental hygiene, eating habits also play a role in the development of caries. Fermentable carbohydrates characteristics of the food, rate of consumption, food protectors, the quality and quantity of saliva indices that determine the remineralization of teeth are factors to be considered. All these elements are analyzed through the sociodemographic, behavioral, physical and biological environment directly or indirectly with diet and caries.
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Incidence, risk factors, and outcome of bacteremia following autologous hematopoietic stem cell transplantation in 720 adult patients.
Ann. Hematol.
PUBLISHED: 04-29-2013
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Bacteremia is the most frequent infectious complication during neutropenia in patients receiving autologous hematopoietic stem cell transplantation (ASCT). The objective of this study was to analyze the incidence, characteristics, risk factors, and outcome of bacteremia during the early period after ASCT. A total of 720 patients undergoing ASCT in two observational prospective consecutive multicenter studies of the Programa Español para el Tratamiento de las Hemopatías group were analyzed. Bacteremia occurred in 20 % of patients. Coagulase-negative Staphylococcus was the most frequent (66 %) among the gram-positive agents and Escherichia coli (49 %) among the gram-negative agents. Multivariate analysis showed that the length of neutropenia <1?×?10(9)/L (more than 9 days) [relative risk (RR) of 2.6, p?
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Adverse prognostic value of MYBL2 overexpression and association with microRNA-30 family in acute myeloid leukemia patients.
Leuk. Res.
PUBLISHED: 04-15-2013
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The MYBL2 gene encodes a transcription factor implicated in cell proliferation and maturation whose amplification or overexpression has been associated with different human malignancies, suggesting that it could be implicated in tumorigenesis. We analyzed MYBL2 expression and its prognostic value in 291 patients with de novo acute myeloid leukemia (AML) and we also evaluated its association with microRNAs 29 and 30 families. MYBL2 expression in AML patients was increased relative to CD34+ cells. Moreover, MYBL2 overexpression was associated with lower expression of miR-30a (P=0.024), miR-30b (P=0.021) and miR-30c (P=0.009). Multivariate analysis showed that MYBL2 expression was an independent factor for disease-free survival (HR 3.0, 95% CI 1.5-6.0, P=0.002) and cumulative incidence of relapse (HR 2.6, 95% CI 1.2-5.6, P=0.015) in patients with an intermediate-risk karyotype. In conclusion, our data showed that MYBL2 expression analysis could be useful to define subgroups of patients with poor prognosis.
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Results of a preoperative autologous blood donation program for patients undergoing elective major spine surgery.
Transfus. Apher. Sci.
PUBLISHED: 04-04-2013
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Spinal surgery has been shown to have a high blood transfusion requirement. Preoperative autologous blood donation (PABD) is a strategy to reduce the allogeneic transfusions in this subset of patients.
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Translation of viral mRNAs that do not require eIF4E is blocked by the inhibitor 4EGI-1.
Virology
PUBLISHED: 03-23-2013
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High throughput screening has rendered new inhibitors of eukaryotic protein synthesis. One such molecule, 4EGI-1 has been reported to selectively block the initiation factor eIF4E. We have investigated the action of this inhibitor on translation directed by several viral mRNAs which, in principle, do not utilize eIF4E. We found that 4EGI-1 inhibits translation directed by poliovirus IRES, in rabbit reticulocyte lysates, to a similar extent as capped mRNA. Moreover, 4EGI-1 inhibits translation driven by poliovirus IRES, both in vitro and in cultured cells, despite cleavage of eIF4G by picornavirus proteases. Finally, translation of vesicular stomatitis virus mRNAs and Sindbis virus subgenomic mRNA is blocked by 4EGI-1 in infected cells to a similar extent as cellular mRNAs. These findings cast doubt on the selective action of this inhibitor, and suggest that this molecule may affect other steps in protein synthesis unrelated to cap recognition by eIF4E.
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Translation without eIF2 promoted by poliovirus 2A protease.
PLoS ONE
PUBLISHED: 07-05-2011
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Poliovirus RNA utilizes eIF2 for the initiation of translation in cell free systems. Remarkably, we now describe that poliovirus translation takes place at late times of infection when eIF2 is inactivated by phosphorylation. By contrast, translation directed by poliovirus RNA is blocked when eIF2 is inactivated at earlier times. Thus, poliovirus RNA translation exhibits a dual mechanism for the initiation of protein synthesis as regards to the requirement for eIF2. Analysis of individual poliovirus non-structural proteins indicates that the presence of 2A(pro) alone is sufficient to provide eIF2 independence for IRES-driven translation. This effect is not observed with a 2A(pro) variant unable to cleave eIF4G. The level of 2A(pro) synthesized in culture cells is crucial for obtaining eIF2 independence. Expression of the N-or C-terminus fragments of eIF4G did not stimulate IRES-driven translation, nor provide eIF2 independence, consistent with the idea that the presence of 2A(pro) at high concentrations is necessary. The finding that 2A(pro) provides eIF2-independent translation opens a new and unsuspected area of research in the field of picornavirus protein synthesis.
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Prognostic value of cytogenetics in adult patients with Philadelphia-negative acute lymphoblastic leukemia.
Ann. Hematol.
PUBLISHED: 06-13-2011
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The prognostic value of cytogenetics in adult acute lymphoblastic leukemia (ALL) is not as established as in childhood ALL. We have analyzed the outcome and prognostic value of karyotype in 84 adults diagnosed with Philadelphia-negative ALL from a single institution that received induction chemotherapy and had successful karyotype performed. The most frequent finding was normal karyotype in 35 (42%) cases, followed by aneuploidies in 20 cases (24%) and t(4;11)(q21;q23)/MLL/AF4 in 5 (6%), and the remaining 24(27%) cases carried miscellaneous clonal abnormalities. The group of patients with t(4;11)(q21;q23)/MLL/AF4, hypodiploidy and low hyperdiploidy (less than 50 chromosomes) showed a worse outcome than those with normal karyotype and miscellaneous abnormalities in terms of overall survival (OS) (3 years OS; 47% vs. 13%, p?=?0.014) and relapse-free survival (RFS) (3 years RFS; 44% vs. 27%, p?=?0.005). Other cytogenetic prognostic classifications reported to date were tested in our series, but any was fully reproducible. In conclusion, karyotype is a useful tool for risk assessment in adult ALL. We have confirmed the bad prognosis of t(4;11)(q21;q23)/MLL/AF4 and hypodiploidy. Besides, low hyperdiploidy could also define a high-risk group of patients who might be candidates for more intensive treatment.
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Update on bacteraemia in oncology and hematology.
Enferm. Infecc. Microbiol. Clin.
PUBLISHED: 04-05-2011
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The present article is an update of the literature on bacteraemia in onco-hematologic patients. A multidisciplinary group of Spanish physicians with an interest in this field selected the most important papers published recently. Papers from the fields of basic science, epidemiology, causative microorganisms and clinical syndromes are discussed. Important aspects of these studies include the assessment of different strategies in the management of fever in neutropenic patients and the validation of specific scores. Moreover, early identification of patients at risk of bacterial and of multi-drug resistant infections is a topic of increasing interest.
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Fragment length analysis screening for detection of CEBPA mutations in intermediate-risk karyotype acute myeloid leukemia.
Ann. Hematol.
PUBLISHED: 04-04-2011
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During last years, molecular markers have been increased as prognostic factors routinely screened in acute myeloid leukemia (AML). Recently, an increasing interest has been reported in introducing to clinical practice screening for mutations in the CCAAT/enhancer-binding protein ? (CEBPA) gene in AML, as it seems to be a good prognostic factor. However, there is no reliable established method for assessing CEBPA mutations during the diagnostic work-up of AMLs. We describe here a straightforward and reliable fragment analysis method based in PCR capillary electrophoresis (PCR-CE) for screening of CEBPA mutations; moreover, we present the results obtained in 151 intermediate-risk karyotype AML patients (aged 16-80 years). The method gave a specificity of 100% and sensitivity of 93% with a lower detection limit of 1-5% for CEBPA mutations. The series found 19 mutations and four polymorphisms in 12 patients, seven of whom (58%) presented two mutations. The overall frequency of CEBPA mutations in AML was 8% (n?=?12). CEBPA mutations showed no coincidence with FLT3-ITD or NPM1 mutations. CEBPA mutation predicted better disease-free survival in the group of patients without FLT3-ITD, NPM, or both genes mutated (HR 3.6, IC 95%; 1.0-13.2, p?=?0.05) and better overall survival in patients younger than 65 of this group without molecular markers (HR 4.0, IC 95%; 1.0-17.4, p?=?0.05). In conclusion, the fragment analysis method based in PCR-CE is a rapid, specific, and sensitive method for CEBPA mutation screening and our results confirm that CEBPA mutations can identify a subgroup of patients with favorable prognosis in AML with intermediate-risk karyotype.
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Translation of viral mRNA without active eIF2: the case of picornaviruses.
PLoS ONE
PUBLISHED: 03-18-2011
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Previous work by several laboratories has established that translation of picornavirus RNA requires active eIF2? for translation in cell free systems or after transfection in culture cells. Strikingly, we have found that encephalomyocarditis virus protein synthesis at late infection times is resistant to inhibitors that induce the phosphorylation of eIF2? whereas translation of encephalomyocarditis virus early during infection is blocked upon inactivation of eIF2? by phosphorylation induced by arsenite. The presence of this compound during the first hour of infection leads to a delay in the appearance of late protein synthesis in encephalomyocarditis virus-infected cells. Depletion of eIF2? also provokes a delay in the kinetics of encephalomyocarditis virus protein synthesis, whereas at late times the levels of viral translation are similar in control or eIF2?-depleted HeLa cells. Immunofluorescence analysis reveals that eIF2?, contrary to eIF4GI, does not colocalize with ribosomes or with encephalomyocarditis virus 3D polymerase. Taken together, these findings support the novel idea that eIF2 is not involved in the translation of encephalomyocarditis virus RNA during late infection. Moreover, other picornaviruses such as foot-and-mouth disease virus, mengovirus and poliovirus do not require active eIF2? when maximal viral translation is taking place. Therefore, translation of picornavirus RNA may exhibit a dual mechanism as regards the participation of eIF2. This factor would be necessary to translate the input genomic RNA, but after viral RNA replication, the mechanism of viral RNA translation switches to one independent of eIF2.
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[Guidelines for the treatment of invasive fungal disease by Aspergillus spp. and other fungi issued by the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC). 2011 Update].
Enferm. Infecc. Microbiol. Clin.
PUBLISHED: 01-13-2011
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The guidelines on the treatment of invasive fungal disease by Aspergillus spp. and other fungi issued by the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) are presented. These recommendations are focused on four clinical categories: oncology-haematology patients, solid organ transplant recipients, patients admitted to intensive care units, and children. An extensive review is made of therapeutical advances and scientific evidence in these settings. These guidelines have been prepared according the SEIMC consensus rules by a working group composed of specialists in infectious diseases, clinical microbiology, critical care medicine, paediatrics and oncology-haematology. Specific recommendations on the prevention of fungal infections in these patients are included.
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Presenting features and treatment outcome of acute promyelocytic leukemia arising after multiple sclerosis.
Haematologica
PUBLISHED: 12-29-2010
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We report the clinical features and treatment outcome of 33 patients with multiple sclerosis who developed acute promyelocytic leukemia. Thirty patients were previously exposed to mitoxantrone. The median latency period between treatment initiation and acute promyelocytic leukemia diagnosis was 32 months. The PML-RARA bcr1 iso-form was identified in 87% of cases. Twenty-nine (90%) patients achieved hematologic remission after all-trans retinoic acid and chemotherapy (n = 31) or arsenic trioxide and all-trans retinoic acid. Consolidation included modified chemotherapy or arsenic trioxide. At a median follow up of 26 months, 23 patients are in complete remission, 4 relapsed and one developed secondary leukemia. The 5-year cumulative incidence of relapse and overall survival were 23% and 68%, respectively. Although treatment heterogeneity and suboptimal post-remission therapy must be taken into account, overall results and development of secondary leukemia in one patient suggest that effective and less toxic agents like arsenic trioxide warrants further investigation in this context.
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Translation driven by picornavirus IRES is hampered from Sindbis virus replicons: rescue by poliovirus 2A protease.
J. Mol. Biol.
PUBLISHED: 05-05-2010
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Alphavirus replicons are very useful for analyzing different aspects of viral molecular biology. They are also useful tools in the development of new vaccines and highly efficient expression of heterologous genes. We have investigated the translatability of Sindbis virus (SV) subgenomic mRNA bearing different 5-untranslated regions, including several viral internal ribosome entry sites (IRESs) from picornaviruses, hepatitis C virus, and cricket paralysis virus. Our findings indicate that all these IRES-containing mRNAs are initially translated in culture cells transfected with the corresponding SV replicon but their translation is inhibited in the late phase of SV replication. Notably, co-expression of different poliovirus (PV) non-structural genes reveals that the protease 2A (2A(pro)) is able to increase translation of subgenomic mRNAs containing the PV or encephalomyocarditis virus IRESs but not of those of hepatitis C virus or cricket paralysis virus. A PV 2A(pro) variant deficient in eukaryotic initiation factor (eIF) 4GI cleavage or PV protease 3C, neither of which cleaves eIF4GI, does not increase picornavirus IRES-driven translation, whereas L protease from foot-and-mouth disease virus also rescues translation. These findings suggest that the replicative foci of SV-infected cells where translation takes place are deficient in components necessary to translate IRES-containing mRNAs. In the case of picornavirus IRESs, cleavage of eIF4GI accomplished by PV 2A(pro) or foot-and-mouth disease virus protease L rescues this inhibition. eIF4GI co-localizes with ribosomes both in cells electroporated with SV replicons bearing the picornavirus IRES and in cells co-electroporated with replicons that express PV 2A(pro). These findings support the idea that eIF4GI cleavage is necessary to rescue the translation driven by picornavirus IRESs in baby hamster kidney cells that express SV replicons.
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DNA methylation profiles and their relationship with cytogenetic status in adult acute myeloid leukemia.
PLoS ONE
PUBLISHED: 03-30-2010
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Aberrant promoter DNA methylation has been shown to play a role in acute myeloid leukemia (AML) pathophysiology. However, further studies to discuss the prognostic value and the relationship of the epigenetic signatures with defined genomic rearrangements in acute myeloid leukemia are required.
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Unrelated transplantation for poor-prognosis adult acute lymphoblastic leukemia: long-term outcome analysis and study of the impact of hematopoietic graft source.
Biol. Blood Marrow Transplant.
PUBLISHED: 02-01-2010
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Adults with high-risk acute lymphoblastic leukemia (HR-ALL) have a poor outcome with standard chemotherapy and usually undergo unrelated stem cell transplantation (SCT) if a matched sibling donor is not available. We analyzed the outcome of adult patients with unrelated SCT for HR-ALL and studied the possible effect of the hematopoietic stem cell source of the transplant. A total of 149 adult patients (median age, 29 years, range, 15-59 years) with HR-ALL underwent unrelated SCT in 13 Spanish institutions between 2000 and 2007. Patients in first complete remission (CR1) at transplantation had at least one adverse prognostic factor (advanced age, adverse cytogenetics, hyperleukocytosis, or slow response to induction therapy). ALL was in CR1 in 81 patients (54%), in second CR (CR2) in 37 patients (25%), in third CR (CR3) in 11 patients (7%), and with overt disease in 20 patients (13%). The hematopoietic source was unrelated cord blood (UCB) in 62 patients and an unrelated donor (UD) in 87 patients. The patients undergoing UCB-SCT and UD-SCT were comparable in terms of the main clinical and biological features of ALL, except for a higher frequency of patients with more overt disease in the UCB-SCT group. There was no statistically significant difference in overall survival (OS) or disease-free survival (DFS) at 5 years between the 2 groups. Treatment-related mortality (TRM) was significantly lower in the UCB-SCT group (P = .021). The probability of relapse at 1 year was 17% (95% confidence interval [CI], 7%-27%) for the UD-SCT group and 27% (95% CI, 14%-40%) for the UCB-SCT group (P = .088), respectively. Only disease status at transplantation (CR1, 41% [95% CI, 18%-64%] vs CR2, 51% [95% CI, 17%-85%] vs advanced disease, 66% [95% CI, 46%-86%]; P = .001) and the absence of chronic graft-versus-host disease (74% [95% CI, 46%-100%] vs 33% [95% CI, 17%-49%]; P = .034) were significant factors for relapse. All unrelated transplantation modalities were associated with high treatment-related mortality for adult HR-ALL patients without a sibling donor. UCB-SCT and UD-SCT were found to be equivalent options. Disease status at transplantation and chronic GVHD were the main factors influencing relapse in both transplantation modalities.
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Rapid detection of KIT mutations in core-binding factor acute myeloid leukemia using high-resolution melting analysis.
J Mol Diagn
PUBLISHED: 07-30-2009
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The most frequent KIT mutations reported in core-binding factor acute myeloid leukemia are point mutations and insertions/deletions in exons 17 and 8. The vast majority of KIT mutation detection procedures are time-consuming, costly, or with a high lower limit of detection. High-resolution melting (HRM) is a gene scanning method that combines simplicity and rapid identification of genetic variants. We describe an HRM method for the simultaneous screening of exons 8 and 17 KIT mutations and report the results obtained in 69 core-binding factor acute myeloid leukemia patients. Mutation detection was compared with sequencing as the gold standard. The HRM method used high-resolution melting master reagents (Roche) and the LightCycler 480 (Roche) platform. HRM was reproducible, showed a lower limit of detection of 1%, and discriminated all patients with mutated KIT from controls without false positive or false negative results. Additionally, most of the mutations were differentiated from the other mutations. KIT mutations were present in 15.9% of patients, showing a higher incidence in inv(16) (25.8%) than in t(8;21) (7.9%). The presence of a KIT mutation was associated with a high white blood cell count, and adult patients with an exon 17 mutation had a higher incidence of relapse. These findings verify that HRM is a reliable, rapid, and sensitive method for KIT mutation screening. Furthermore, our study corroborates the unfavorable prognosis associated with exon 17 KIT mutations.
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[Micafungin in invasive candidiasis among oncohematological patients].
Rev Iberoam Micol
PUBLISHED: 02-12-2009
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Invasive candidiasis is a severe infection among onco-hematological patients, with an attributable mortality around 40%. Micafungin has shown efficacy in antifungal prophylaxis among hematopoietic stem cell transplant recipients and in the treatment of esophageal candidiasis.
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Dual mechanism for the translation of subgenomic mRNA from Sindbis virus in infected and uninfected cells.
PLoS ONE
PUBLISHED: 02-12-2009
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Infection of BHK cells by Sindbis virus (SV) gives rise to a profound inhibition of cellular protein synthesis, whereas translation of viral subgenomic mRNA that encodes viral structural proteins, continues for hours. To gain further knowledge on the mechanism by which this subgenomic mRNA is translated, the requirements for some initiation factors (eIFs) and for the presence of the initiator AUG were examined both in infected and in uninfected cells. To this end, BHK cells were transfected with different SV replicons or with in vitro made SV subgenomic mRNAs after inactivation of some eIFs. Specifically, eIF4G was cleaved by expression of the poliovirus 2A protease (2A(pro)) and the alpha subunit of eIF2 was inactivated by phosphorylation induced by arsenite treatment. Moreover, cellular location of these and other translation components was analyzed in BHK infected cells by confocal microscopy. Cleavage of eIF4G by poliovirus 2A(pro) does not hamper translation of subgenomic mRNA in SV infected cells, but bisection of this factor blocks subgenomic mRNA translation in uninfected cells or in cell-free systems. SV infection induces phosphorylation of eIF2alpha, a process that is increased by arsenite treatment. Under these conditions, translation of subgenomic mRNA occurs to almost the same extent as controls in the infected cells but is drastically inhibited in uninfected cells. Notably, the correct initiation site on the subgenomic mRNA is still partially recognized when the initiation codon AUG is modified to other codons only in infected cells. Finally, immunolocalization of different eIFs reveals that eIF2 alpha and eIF4G are excluded from the foci, where viral RNA replication occurs, while eIF3, eEF2 and ribosomes concentrate in these regions. These findings support the notion that canonical initiation takes place when the subgenomic mRNA is translated out of the infection context, while initiation can occur without some eIFs and even at non-AUG codons in infected cells.
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Translation directed by hepatitis A virus IRES in the absence of active eIF4F complex and eIF2.
PLoS ONE
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Translation directed by several picornavirus IRES elements can usually take place after cleavage of eIF4G by picornavirus proteases 2A(pro) or L(pro). The hepatitis A virus (HAV) IRES is thought to be an exception to this rule because it requires intact eIF4F complex for translation. In line with previous results we report that poliovirus (PV) 2A(pro) strongly blocks protein synthesis directed by HAV IRES. However, in contrast to previous findings we now demonstrate that eIF4G cleavage by foot-and-mouth disease virus (FMDV) L(pro) strongly stimulates HAV IRES-driven translation. Thus, this is the first observation that 2A(pro) and L(pro) exhibit opposite effects to what was previously thought to be the case in HAV IRES. This effect has been observed both in hamster BHK and human hepatoma Huh7 cells. In addition, this stimulation of translation is also observed in cell free systems after addition of purified L(pro). Notably, in presence of this FMDV protease, translation directed by HAV IRES takes place when eIF2? has been inactivated by phosphorylation. Our present findings clearly demonstrate that protein synthesis directed by HAV IRES can occur when eIF4G has been cleaved and after inactivation of eIF2. Therefore, translation directed by HAV IRES without intact eIF4G and active eIF2 is similar to that observed with other picornavirus IRESs.
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Phosphorylation of eIF2? is responsible for the failure of the picornavirus internal ribosome entry site to direct translation from Sindbis virus replicons.
J. Gen. Virol.
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Translation directed by the poliovirus (PV) or encephalomyocarditis virus (EMCV) internal ribosome entry site (IRES) is very inefficient when expressed from Sindbis virus (SV) replicons. This inhibition can be rescued by co-expression of PV 2A protease (2A(pro)). Inhibition correlates with the extensive phosphorylation of eukaryotic initiation factor (eIF) 2? induced by SV replication. Confirmation that PV or EMCV IRES-driven translation can function when eIF2? is not phosphorylated was obtained in dsRNA-activated protein kinase knockout mouse embryonic fibroblasts (PKR(-/-) MEFs), where SV replication cannot induce eIF2? phosphorylation, and in variant S51A MEFs that express an unphosphorylatable eIF2?. In these cells, PV or EMCV IRES-dependent translation operated more efficiently than in wild-type MEFs. However, this translation was potently blocked when eIF2? was phosphorylated by the addition of thapsigargin to PKR(-/-) MEFs. In addition, when wild-type eIF2? was expressed in S51A MEFs or PKR was expressed in PKR(-/-) MEFs, PV IRES-dependent translation decreased. In both cases, the decrease in PV IRES-dependent translation correlated with the phosphorylation of eIF2?. Notably, PV 2A(pro) expression rescued PV IRES-driven translation in thapsigargin-treated PKR(-/-) MEFs. Taken together, these results demonstrated that PV IRES-driven translation can take place from SV replicons if eIF2? remains unphosphorylated. Remarkably, PV IRES-dependent translation was fully functional in this system when PV 2A(pro) was present, even if eIF2? was phosphorylated.
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Requirements for eIF4A and eIF2 during translation of Sindbis virus subgenomic mRNA in vertebrate and invertebrate host cells.
Cell. Microbiol.
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We have examined the requirements for the initiation factors (eIFs) eIF4A and eIF2 to translate Sindbis virus (SV) subgenomic mRNA (sgmRNA) in the natural hosts of SV: vertebrate and arthropod cells. Notably, this viral mRNA does not utilize eIF4A in SV-infected mammalian cells. However, eIF4A is required to translate this mRNA in transfected cells. Therefore, SV sgmRNA exhibits a dual mechanism for translation with respect to the use of eIF4A. Interestingly, SV genomic mRNA requires eIF4A for translation during the early phase of infection. In sharp contrast to what is observed in mammalian cells, active eIF2 is necessary to translate SV sgmRNA in mosquito cells. However, eIF4A is not necessary for SV sgmRNA translation in this cell line. In the SV sgmRNA coding region, proximal to the initiation codon is a hairpin structure that confers eIF2 independence only in mammalian cells infected by SV. Strikingly, this structure does not provide independence for eIF4A neither in mammalian nor in mosquito cells. These findings provide the first evidence of different eIF requirements for translation of SV sgmRNA in vertebrate and invertebrate cells. These observations can help to understand the interaction of SV with its host cells.
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Bone marrow-derived cells from male donors do not contribute to the endometrial side population of the recipient.
PLoS ONE
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Accumulated evidence demonstrates the existence of bone marrow-derived cells origin in the endometria of women undergoing bone marrow transplantation (BMT). In these reports, cells of a bone marrow (BM) origin are able to differentiate into endometrial cells, although their contribution to endometrial regeneration is not yet clear. We have previously demonstrated the functional relevance of side population (SP) cells as the endogenous source of somatic stem cells (SSC) in the human endometrium. The present work aims to understand the presence and contribution of bone marrow-derived cells to the endometrium and the endometrial SP population of women who received BMT from male donors. Five female recipients with spontaneous or induced menstruations were selected and their endometrium was examined for the contribution of XY donor-derived cells using fluorescent in situ hybridization (FISH), telomapping and SP method investigation. We confirm the presence of XY donor-derived cells in the recipient endometrium ranging from 1.7% to 2.62%. We also identify 0.45-0.85% of the donor-derived cells in the epithelial compartment displaying CD9 marker, and 1.0-1.83% of the Vimentin-positive XY donor-derived cells in the stromal compartment. Although the percentage of endometrial SP cells decreased, possibly being due to chemotherapy applied to these patients, they were not formed by XY donor-derived cells, donor BM cells were not associated with the stem cell (SC) niches assessed by telomapping technique, and engraftment percentages were very low with no correlation between time from transplant and engraftment efficiency, suggesting random terminal differentiation. In conclusion, XY donor-derived cells of a BM origin may be considered a limited exogenous source of transdifferentiated endometrial cells rather than a cyclic source of BM donor-derived stem cells.
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[Guidelines for diagnosis, treatment and monitoring of primary immune thrombocytopenia].
Med Clin (Barc)
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The consensus document on the diagnosis, treatment and monitoring of primary immune thrombocytopenia was developed in 2010 by specialists with recognized expertise in this disease under the auspices of the Spanish Society of Hematology and Hemotherapy and the Spanish Society of Pediatric Hematology and Oncology, with the aim to adapt to Spain the recommendations of the recently published international consensus documents. The decision to start treatment is based on bleeding manifestations and platelet count (<20×10(9)/L). The first-line treatment is corticosteroids, albeit for a limited period of 4-6 weeks. The addition of intravenous immunoglobulin is reserved to patients with severe bleeding. Splenectomy is the most effective second-line treatment. For patients refractory to splenectomy and those with contraindications or patient refusal, the new thrombopoietic agents are the drugs of choice due to their efficacy and excellent safety profile. The other treatment options have highly variable response rates, and the absence of controlled studies does not allow to establish clear recommendations. Monitoring should be individualized. In patients without active treatment, blood counts are recommended every 3-6 months, and the patient should be instructed to consult in case of bleeding, surgery or invasive procedure and pregnancy. In most of the pediatric population, the disease tends to spontaneous remission. High-dose corticosteroids in short course and intravenous immunoglobulin are the treatment of choice. Second- and further-line treatments should be monitored in specialized centers.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.