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1.
Bone Marrow Transplant ; 50(3): 380-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25486582

RESUMO

Autologous hematopoietic SCT (AHSCT) has been investigated in the past as a therapeutic alternative for multiple sclerosis (MS). Despite advances in clinical management, knowledge about mechanisms involved with clinical remission post transplantation is still limited. Abnormal microRNA and gene expression patterns were described in MS and have been suggested as disease biomarkers and potential therapeutic targets. Here we assessed T- and B-cell reconstitution, microRNAs and immunoregulatory gene expression after AHSCT. Early immune reconstitution was mainly driven by peripheral homeostatic proliferation. AHSCT increased CD4(+)CD25(hi)FoxP3(+) regulatory T-cell counts and expression of CTLA-4 and GITR (glucocorticoid-induced TNFR) on CD4(+)CD25(hi) T cells. We found transient increase in exhausted PD-1(+) T cells and of suppressive CD8(+)CD28(-)CD57(+) T cells. At baseline, CD4(+) and CD8(+) T cells from MS patients presented upregulated miR-16, miR-155 and miR-142-3p and downregulated FOXP3, FOXO1, PDCD1 and IRF2BP2. After transplantation, the expression of FOXP3, FOXO1, PDCD1 and IRF2BP2 increased, reaching control levels at 2 years. Expression of miR-16, miR-155 and miR-142-3p decreased towards normal levels at 6 months post therapy, remaining downregulated until the end of follow-up. These data strongly suggest that AHSCT normalizes microRNA and gene expression, thereby improving the immunoregulatory network. These mechanisms may be important for disease control in the early periods after AHSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , MicroRNAs/biossíntese , Esclerose Múltipla/genética , Esclerose Múltipla/terapia , Condicionamento Pré-Transplante/métodos , Adulto , Feminino , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Esclerose Múltipla/metabolismo , Transplante Autólogo , Adulto Jovem
2.
Anim Reprod Sci ; 146(3-4): 103-10, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24646635

RESUMO

The objective of this study was to determine the effect of different centrifugation forces in bovine sperm separation by discontinuous Percoll gradients for in vitro fertilization IVF. The semen samples from each bull were pooled or each bull were centrifuged separately and centrifuged in discontinuous Percoll gradients (30, 60 and 90%) at different forces: F1 (9000×g), F2 (6500×g), F3 (4500×g) and F4 (2200×g), according experiment. The sperm samples were evaluated to determine the concentration, motility, vigor, morphology, reactive oxygen species (ROS), integrity of the plasma membrane, lipid peroxidation, antioxidants and embryo development were also evaluated. No difference was observed in the concentration of sperm submitted to different centrifugation forces. The total percentage of motile sperm was increased after centrifugation at F3 and F4, and the ROS production at F1 was greater than the other forces. When the bulls semen were processed individually, no significant differences were observed for the sperm quality parameters between F1 and F4, including lipid peroxidation, antioxidants, cleavage rate and average time to the first cleavage. This work demonstrated for the first time that centrifugation at 2200×g enhanced the sperm penetration and fertilization rates without reducing sperm recovery compared to the typical centrifugation force (9000×g) currently used by the commercial bovine IVF industry.


Assuntos
Bovinos/fisiologia , Centrifugação com Gradiente de Concentração/veterinária , Fertilização in vitro/veterinária , Povidona , Dióxido de Silício , Espermatozoides/fisiologia , Animais , Bovinos/embriologia , Centrifugação com Gradiente de Concentração/métodos , Feminino , Masculino , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Análise do Sêmen/veterinária , Espermatozoides/citologia
3.
Theriogenology ; 79(5): 778-83, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23312719

RESUMO

The objective was to use subzonal sperm injection (SUZI) to understand sperm penetration patterns and to use intracytoplasmic sperm injection (ICSI) to improve production of bovine embryos using poor quality gametes. In experiment 1, poor versus good quality oocytes were fertilized with sperm from two bulls, A and B, with poor and good sperm vigor, respectively. The blastocyst rate was higher for good versus poor quality oocytes (23.3% vs. 11.1%, P < 0.05), regardless of the bull used. There was no significant difference in blastocyst rate for bull A (low vigor) regardless of oocyte quality, and for bull B (high vigor), blastocyst rate was better for good versus poor quality oocytes (25.7% vs. 9.2%, P < 0.05). In experiment 2, poor quality oocytes were subjected to SUZI. The oocyte penetration rate was lower for bull A than for bull B (29.6% vs. 53.8%, P < 0.05), when SUZI was performed within 1 hour after sperm processing. However, when SUZI was performed 2 to 3 hours after sperm processing, penetrating capacity was similar between bulls, but for bull B, penetrating capacity significantly decreased after 3 hours of sperm processing. In an attempt to overcome sperm penetrating disorders, poor and good quality oocytes were subjected to ICSI (experiment 3). Irrespective of the bull or of the oocyte quality grade, there were no differences in cleavage or blastocyst rates. Both bulls had distinct IVF embryo production rates, which we inferred were because of particular individual sperm characteristics. In conclusion, ICSI was an effective means to achieve in vitro production of bovine embryos with gametes of variable quality.


Assuntos
Bovinos/fisiologia , Oócitos/fisiologia , Injeções de Esperma Intracitoplásmicas/veterinária , Animais , Desenvolvimento Embrionário , Feminino , Masculino , Gravidez , Injeções de Esperma Intracitoplásmicas/métodos
4.
Theriogenology ; 75(3): 429-33, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20961608

RESUMO

The objective of this study was to determine the effect of fetal calf serum (FCS) on the quality of in vitro produced bovine embryos. Cumulus oocyte-complexes (COCs, n = 2 449) recovered by ovum pick-up from Bos taurus indicus donors were randomly assigned to experimental groups. Sperm selected by Percoll gradient was used for in vitro fertilization (insemination = Day 0). In Experiment 1 (n = 1 745 COCs), zygotes were cultured in vitro in Synthetic Oviduct Fluid + 4 mg/mL of bovine serum albumin (BSA), or BSA + 2% FCS (BSA+FCS). In Experiment 2 (n = 704 COCs), the COCs were cultured in SOF + BSA, BSA + 2% FCS, or BSA + 2% FCS on D4 (BSA + FCSD4). In Experiment 1, blastocyst yield (51%) and Quality I blastocysts (41%) at Day 7 were higher (P < 0.05) in the BSA + FCS treatment than in BSA (42 and 30%, respectively). In Experiment 2, blastocyst yield was higher (P < 0.05) in the BSA+FCS (47%) treatment. Quality I blastocyst yield was higher (P < 0.05) for BSA + FCS (34%) and BSA+FCSD4 (32%) compared to the BSA treatment (20%). A total of 820 embryos were transferred, with no significant differences among groups in pregnancy rates. In conclusion, in vitro culture in SOFaaci + BSA + FCS enhanced blastocyst yield and Quality I blastocysts; adding FCS to the culture medium increased the efficiency of IVP of bovine embryos.


Assuntos
Bovinos/embriologia , Desenvolvimento Embrionário , Fertilização in vitro/veterinária , Sangue Fetal/fisiologia , Animais , Blastocisto/fisiologia , Células Cultivadas , Meios de Cultura , Células do Cúmulo , Técnicas de Cultura Embrionária/veterinária , Transferência Embrionária/veterinária , Feminino , Masculino , Oócitos , Gravidez , Soroalbumina Bovina/administração & dosagem
5.
Reprod Domest Anim ; 40(1): 19-22, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15654996

RESUMO

The aim of this study was to increase the bovine embryonic development rate, adding recombinant human growth hormone (rhGH) to maturation medium of bovine oocytes. Oocytes were matured for 24 h in TCM 199 Earle's salts and five treatments were developed: T1, 0.01 IU/ml of recombinant human follicle stimulating hormone (rhFSH); T2, 0.01 IU/ml of rhFSH + 100 ng/ml of rhGH; T3, 0.01 IU/ml of rhFSH + 1000 ng/ml of rhGH; T4, 100 ng/ml of rhGH; and T5, 1000 ng/ml of rhGH at 39 degrees C and 5% of CO(2) in air and saturated humidity. In vitro fertilization from cumulus-oocyte complexes was conducted in TALP-Fert medium (18-22 h) and spermatozoa were selected by Percoll gradient. Zygotes were incubated in SOFaaci medium in 5% of CO(2) in air, 5% of O(2) at 39 degrees C and saturated humidity for 11 days. There was no statistical difference in cleavage rate and embryo production on day 7 and day 9 among treatments. However, the hatching rate increased significantly in the T4 and T5 treatments (11.0 and 12.8%, respectively), compared with the T1 treatment (4.6%) (p < 0.05). Therefore, the rhGH addition to the oocyte maturation medium showed beneficial effects on the hatching rate of in vitro-produced bovine embryos.


Assuntos
Fertilização in vitro/veterinária , Hormônio do Crescimento Humano/farmacologia , Oócitos/efeitos dos fármacos , Animais , Bovinos , Meios de Cultura/farmacologia , Feminino , Humanos , Oócitos/crescimento & desenvolvimento , Gravidez , Proteínas Recombinantes/farmacologia
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