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21.
Chikhlikar P Barros de Arruda L Agrawal S Byrne B Guggino W August JT Marques ET 《Virology》2004,323(2):220-232
The immune responses to an HIV-1 p55Gag vaccine encoded as a DNA chimera with the lysosomal associated membrane protein-1 (LAMP) have been examined for the effect of the addition of the inverted terminal repeat (ITR) sequences of the adeno-associated virus (AAV) to the DNA plasmid construct, and of packaging the LAMP/gag gene as a recombinant AAV vector (rAAV). DNA plasmids encoding Gag and the LAMP/Gag protein chimera were constructed in two vectors, the pcDNA3.1 and a corresponding plasmid containing the ITR sequences (pITR) flanking the expression elements of the plasmid, and the pITR LAMP/gag DNA plasmid was encapsidated in the rAAV vector. Human 293 cells transfected in vitro with LAMP/gag plasmids either in pcDNA3.1 or pITR produced much Gag protein in cell extracts (1.6 and 2.2 ng of Gag/mg of protein, respectively). The immune responses of mice to immunization with these constructs were examined under three protocols: DNA prime/DNA boost, DNA prime/rAAV boost, and a single rAAV immunization. The results demonstrated that under DNA prime/DNA boost protocol, the "naked" DNA vaccines encoding the LAMP/gag chimera, either as pcDNA3.1 or pITR DNA plasmid constructs, elicited strong CD4(+) T cell responses. In contrast, significantly higher levels of CD8(+) and antibody responses were observed with the pITR-DNA constructs. Immunization with the rAAV vector under the DNA prime/rAAV boost protocol resulted in sustained T cell responses and a markedly increased antibody response, predominantly of the IgG(1) isotype resulting from the activation of the Th2 subset of CD4(+) T cells, that was sustained for at least 5 months after immunization. 相似文献
22.
da Cunha JP Nakayasu ES Elias MC Pimenta DC Téllez-Iñón MT Rojas F Muñoz MJ Manuel M Almeida IC Schenkman S 《Molecular and biochemical parasitology》2005,140(1):75-86
Histone H1 of most eukaryotes is phosphorylated during the cell cycle progression and seems to play a role in the regulation of chromatin structure, affecting replication and chromosome condensation. In trypanosomatids, histone H1 lacks the globular domain and is shorter when compared with the histone of other eukaryotes. We have previously shown that in Trypanosoma cruzi, the agent of Chagas' disease, histone H1 is phosphorylated and this increases its dissociation from chromatin. Here, we demonstrate using mass spectrometry analysis that T. cruzi histone H1 is only phosphorylated at the serine 12 in the sequence SPKK, a typical cyclin-dependent kinase site. We also found a correlation between the phosphorylation state of histone H1 and the cell cycle. Hydroxyurea and lactacystin, which, respectively, arrest parasites at the G1/S and G2/M stages of the cell cycle, increased the level of histone H1 phosphorylation. Cyclin-dependent kinase-related enzymes TzCRK3, and less intensely the TzCRK1 were able to phosphorylate histone H1 in vitro. Histone H1 dephosphorylation was prevented by treating the parasites with okadaic acid but not with calyculin A. These findings suggest that T. cruzi histone H1 phosphorylation is promoted by cyclin dependent kinases, present during S through G2 phase of the cell cycle, and its dephosphorylation is promoted by specific phosphatases. 相似文献
23.
Ernesto Falcidia Agata Grillo Piero Pavone Nunzio Cutuli Haruo Takabayashi Rosario R. Trifiletti Conrad T. Gilliam 《American journal of medical genetics. Part A》2001,101(3):262-267
The isolation and analysis of nucleated fetal cells (NFCs) from maternal blood may represent a new approach to noninvasive prenatal diagnosis. Although promising, these techniques require highly accurate separation of NFCs from nucleated cells of maternal origin; the two major problems limiting these techniques are the relative rarity of fetal cells in maternal blood and the need to establish their fetal origin. We now report a novel procedure that has allowed accurate separation of NFCs from maternal cells. The technique reported involves direct micromanipulator isolation of histochemically identified hemoglobin F‐positive nucleated cells to obtain fetal nucleated red blood cells (FNRBCs) of high yield and purity. Using this technique, followed by cell‐by‐cell multicolor fluorescence in situ hybridization (FISH) analysis of purified FNRBCs, we were able to detect some of the most common human aneuploidies (including Down syndrome, Klinefelter syndrome, and trisomy 13) in 33 pregnant women referred for amniocentesis. The procedure used, which can be completed in <72 hrs, produced complete concordance with the results of amniocentesis. We also confirm findings of prior studies suggesting that the number of FNRBCs in maternal circulation is remarkably higher in abnormal pregnancies than in normal pregnancies, especially in women carrying a fetus with trisomy 21. © 2001 Wiley‐Liss, Inc. 相似文献
24.
Begoa Pea Marcelo Aroca Ernesto Prez Antonio Bello Evaristo Riande Rosario Benavente 《Macromolecular chemistry and physics.》1997,198(5):1691-1699
The characteristic ratios of three samples of poly(1-hexadecene) with different tacticities were evaluated from intrinsic viscosity and molecular weight data obtained with a size exclusion chromatograph with dual (concentration plus viscosity) detector. No significant differences were found for the characteristic ratio in the studied range of tacticities. Theoretical calculations for the unperturbed dimensions were also performed for these samples by using the rotational isomeric state model, and compared with the experimental results. 相似文献
25.
The karyotype of a mouse trapped in a hybrid zone between a Robertsonian (Rb) population (2n=22) and a population with the standard karyotype (2n=40-all-telocentrics) shows two Rb chromosomes with new arm compositions. We suggest that whole-arm reciprocal translocations between Rb chromosomes gave rise to the new chromosome constitution and that such events can greatly help in understanding house mouse karyotype diversification and chromosomal speciation. 相似文献
26.
Anthony J Sharp Paul E Polak Vittoria Simonini Shao X Lin Jill C Richardson Ernesto R Bongarzone Douglas L Feinstein 《Journal of neuroinflammation》2008,5(1):33
Background
The purinergic receptor P2x7 is expressed on myeloid cells as well as on CNS glial cells, and P2x7 activation has been shown to increase both glial and T-cell activation. These properties suggest a role in the development of autoimmune disease including multiple sclerosis. 相似文献27.
Dawson Luke P. Dinh Diem T. Stub Dion Ahern Susannah Bloom Jason E. Duffy Stephen J. Lefkovits Jeffrey Brennan Angela Reid Christopher M. Oqueli Ernesto 《Quality of life research》2022,31(8):2375-2385
Quality of Life Research - During the COVID-19 pandemic, widespread public health measures were implemented to control community transmission. The association between these measures and... 相似文献
28.
Amadio Eliane Martins Marcos Rodrigo Labat Serra Andrey Jorge dos Santos Solange Almeida Caires Jheniphe Rocha Fernandes Guilherme Henrique Cardosos Leal-Junior Ernesto Cesar Ferrari João Carlos Correa de Tarso Camillo de Carvalho Paulo 《Lasers in medical science》2021,36(7):1427-1435
Lasers in Medical Science - Photobiomodulation therapy (PBMT) has been indicated for enforcement on healing skin wounds. This study evaluated the effects of PBMT on the healing of skin wounds... 相似文献
29.
Katharine E. Caldwell Al Lulla Collyn T. Murray Rahul R. Handa Ernesto J. Romo Jason W. Wagner Paul E. Wise Jennifer M. Leonard Michael M. Awad 《American journal of surgery》2021,221(2):285-290
BackgroundSuccessful trauma resuscitation relies on multi-disciplinary collaboration. In most academic programs, general surgery (GS) and emergency medicine (EM) residents rarely train together before functioning as a team.MethodsIn our Multi-Disciplinary Trauma Evaluation and Management Simulation (MD-TEAMS), EM and GS residents completed manikin-based trauma scenarios and were evaluated on resuscitation and communication skills. Residents were surveyed on confidence surrounding training objectives.ResultsResidents showed improved confidence running trauma scenarios in multi-disciplinary teams. Residents received lower communication scores from same-discipline vs cross-discipline faculty. EM residents scored higher in evaluation and planning domains; GS residents scored higher in action processes; groups scored equally in team management. Strong correlation existed between team leader communication and resuscitative skill completion.ConclusionMD-TEAMS demonstrated correlation between communication and resuscitation checklist item completion and communication differences by resident specialty. In the future, we plan to evaluate training-related resident behavior changes and specialty-specific communication differences by residents. 相似文献
30.
Gustavo Martinez-Mier Pedro I. Moreno-Ley Luis F. Budar-Fernández Marco T. Méndez-López Carlos A. Allende-Castellanos Luis A. Jiménez-López Daniel A. Barrera-Amoros Edgar Aguilar-Sandoval Maritza De la Paz-Román Ernesto Soto-Miranda Yamilli Rivera-Sanchez Mónica Martínez-Maldonado 《Transplantation proceedings》2021,53(3):1005-1009
ContextThymoglobulin is used effectively as induction agent in kidney transplantation but the optimal dose is not well established.ObjectiveDemonstrate that low-dose thymoglobulin (3 mg/kg) has similar efficacy and safety compared to basiliximab induction in low-risk kidney transplantation under standard maintenance immunosuppressionDesign, Setting, ParticipantsProspective randomized study in kidney transplant patients (12/2016-05/2018). Inclusion criteria: Recipients > 18 years, first living donor transplant. Exclusion criteria: Second and multiorgan transplant, ABO incompatibility, positive cross-match, panel reactive antibodies (PRA) > 30%, positive donor-specific antibody, human immunodeficiency virus, hepatitis B surface antigen, hepatitis C virus positive, white blood cells < 2000 cells/mm3, platelets < 75,000 cells/mm3 and malignancy.InterventionGroup A: basiliximab (20 mg D0 and D4). Group B: thymoglobulin (3 mg/kg total). Maintenance immunosuppression: tacrolimus, mycophenolate mofetil, and steroids.Main Outcome MeasuresBiopsy-proven acute rejection (BPAR), delayed graft function, slow graft function, leukopenia, infections, adverse events, graft loss, estimated glomerular filtration rate, and death within 12 months.Results100 patients (basiliximab, n = 53) (thymoglobulin, n = 47) were included. Donor and recipient characteristics were similar except for longer dialysis (basiliximab), PRA class I (1.2% basiliximab, 4.5% thymoglobulin), HLA match (basiliximab 2.8, thymoglobulin 2.2), and cytomegalovirus status. BPAR rate was basiliximab 3.8% and thymoglobulin 6.4% (P = ns). Delayed graft function (basiliximab 3.8%; thymoglobulin 4.3%), slow graft function, and 12-month leukopenia (basiliximab 11.3%, thymoglobulin 21.3%) were similar between groups (P = ns). There was no difference in infections and adverse events between groups. Patient and graft survival were as follows: basiliximab 98.1% and 92.5%, thymoglobulin 100% and 93.6% (P = ns).ConclusionLow-dose thymoglobulin induction (3 mg/kg) can be used effectively and safely in low-risk kidney transplantation with good results during the first year post-transplant. 相似文献