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1.
PurposeTo investigate impact of the one‐carbon metabolism (OCM) on oocyte maturity and embryo development.MethodsThis prospective study analyzed 18 women who agreed to participate. We measured the OCM biomarkers’ concentrations including Vitamin B12 (VB12), folic acid (FA), and homocysteine (Hcy) in serum and follicular fluid (FF), and assessed their correlation. We also evaluated the influence of such OCM biomarker concentrations in mono‐FF on oocyte maturation, fertilization, embryo quality, and consequent pregnancy after embryo transfers.ResultsAll biomarkers showed a high concentration variability in different follicles of each woman, but their mean levels correlated with the serum levels. Among the 106 collected oocytes, 92 were mature, 59 were fertilized, and 16 yielded good‐quality embryos. We performed 26 single embryo transfers, and 7 patients achieved clinical pregnancies. VB12 concentration (FF) was significantly lower in fertilized than unfertilized oocytes by univariate analysis. In multivariate logistic analysis, a significant correlation was found between FA concentration (FF) <14.25 ng/mL and good‐quality embryos and between Hcy concentration (FF) <4.9 nmol/mL and clinical pregnancy.ConclusionOCM in FF may affect fertilization, embryo quality, and clinical pregnancy.  相似文献   
2.
Cytosolic isocitrate dehydrogenase 1 (IDH1) with an R132H mutation in brain tumors loses its enzymatic activity for catalyzing isocitrate to α-ketoglutarate (α-KG) and acquires new activity whereby it converts α-KG to 2-hydroxyglutarate. The IDH1 mutation induces down-regulation of tricarboxylic acid cycle intermediates and up-regulation of lipid metabolism. Sterol regulatory element-binding proteins (SREBPs) regulate not only the synthesis of cholesterol and fatty acids but also acyclin-dependent kinase inhibitor p21 that halts the cell cycle at G1. Here we show that SREBPs were up-regulated in U87 human glioblastoma cells transfected with an IDH1R132H-expression plasmid. Small interfering ribonucleic acid (siRNA) for SREBP1 specifically decreased p21 messenger RNA (mRNA) levels independent of the p53 pathway. In IDH1R132H-expressing U87 cells, phosphorylation of Retinoblastoma (Rb) protein also decreased. We propose that metabolic changes induced by the IDH1 mutation enhance p21 expression via SREBP1 and inhibit phosphorylation of Rb, which slows progressionof the cell cycle and may be associated with non-aggressive features of gliomas with an IDH1 mutation.  相似文献   
3.
Production of recombinant adeno-associated virus (rAAV) results in substantial quantities of empty capsids or virus-like particles (VLPs), virus protein shells without the vector genome. The contaminating VLPs would interfere with transduction by competing for cell-surface receptors and, when administered in vivo, contribute to antigen load, which may elicit a stronger immune response. Density-gradient ultracentrifugation provides a means to separate VLPs from rAAV particles, but is not feasible for large-scale preparations of vectors. Since the compositions of the VLP and vector differ by the single-stranded DNA genome, we hypothesized that the isoelectric point of the vector may differ from that of the VLP. In an attempt to separate type 1 rAAV particles from VLPs by ion-exchange chromatography, we tested a number of buffer systems and found that trimethylammonium sulfate, or [(CH3)4N]2SO4, effectively separated rAAV1 particles from VLPs. The rAAV1-GFP chromatographically separated from VLPs induced stronger GFP expression in HEK293 cells than rAAV1-GFP contaminated with VLPs. The transduction of mouse muscles with rAAV1-SEAP (secreted form of alkaline phosphatase) isolated from VLPs also showed higher serum SEAP levels than rAAV1-SEAP with VLPs. These results suggest that chromatographic separation of rAAV1 from empty capsids increased the efficacy of rAAV1.  相似文献   
4.
Sato K  Ozaki K  Oh I  Meguro A  Hatanaka K  Nagai T  Muroi K  Ozawa K 《Blood》2007,109(1):228-234
The molecular mechanisms by which mesenchymal stem cells (MSCs) suppress T-cell proliferation are poorly understood, and whether a soluble factor plays a major role remains controversial. Here we demonstrate that the T-cell-receptor complex is not a target for the suppression, suggesting that downstream signals mediate the suppression. We found that Stat5 phosphorylation in T cells is suppressed in the presence of MSCs and that nitric oxide (NO) is involved in the suppression of Stat5 phosphorylation and T-cell proliferation. The induction of inducible NO synthase (NOS) was readily detected in MSCs but not T cells, and a specific inhibitor of NOS reversed the suppression of Stat5 phosphorylation and T-cell proliferation. This production of NO in the presence of MSCs was mediated by CD4 or CD8 T cells but not by CD19 B cells. Furthermore, inhibitors of prostaglandin synthase or NOS restored the proliferation of T cells, whereas an inhibitor of indoleamine 2,3-dioxygenase and a transforming growth factor-beta-neutralizing antibody had no effect. Finally, MSCs from inducible NOS-/- mice had a reduced ability to suppress T-cell proliferation. Taken together, these results suggest that NO produced by MSCs is one of the major mediators of T-cell suppression by MSCs.  相似文献   
5.
6.
BackgroundIn the phase III MDS-005 study of patients with lower-risk, non-del(5q) myelodysplastic syndromes, lenalidomide was associated with a higher rate of ≥ 8 weeks red blood cell transfusion independence (RBC-TI) compared with placebo, but also with a higher risk of hematologic adverse events (AEs).Patients and MethodsThis analysis evaluated the ratio of clinical benefit-risk in patients treated with lenalidomide or placebo, and assessed the effect of lenalidomide dose reductions on response. Clinical benefit was a composite endpoint defined as RBC-TI, transfusion reduction ≥ 4 units packed red blood cells, hemoglobin increase ≥ 1.5 g/dL, or cytogenetic response.ResultsThe rate of clinical benefit was higher with lenalidomide than with placebo (31.9% vs. 3.8%). The ratio of response (RBC-TI and clinical benefit) to risk (hematologic AEs) favored lenalidomide over placebo. Patients who underwent ≥ 1 lenalidomide dose reduction had a longer duration of treatment, received a higher cumulative dose, and were more likely to experience clinical benefit versus patients without dose reductions.ConclusionDespite the occurrence of hematologic AEs, the overall benefit-risk profile supported lenalidomide treatment. Appropriate management of hematologic AEs by dose reductions may help patients with myelodysplastic syndromes to remain on treatment and achieve clinical benefit.  相似文献   
7.
The interleukin 21 (IL-21) receptor is expressed on T-cells, B-cells, and natural killer cells, and IL-21 is critical for regulating immunoglobulin production in vivo in cooperation with IL-4. So far, however, little is known about a role for IL-21 outside the immune system. We investigated the effect of IL-21 on hematopoiesis in vivo by using the hydrodynamics gene-delivery method. Overexpression of IL-21 increases Sca-1+ cells in the periphery and spleen. It also increases the numbers of c-Kit+, Sca-1+, and lineage-/low (KSL) cells and colony-forming units-granulocyte-macrophage (CFU-GM) in the spleen, indicating the expansion of hematopoietic progenitor cells. We found that even in RAG2-/- mice, which lack mature T-cells and B-cells, IL-21 induced an increase in KSL cells and CFU-GM in the spleen. These results demonstrate that IL-21 can induce the expansion of hematopoietic progenitor cells in vivo, even in the absence of mature T-cells and B-cells.  相似文献   
8.
A 71-year-old man visited our hospital complaining of fever and a bleeding tendency. The peripheral blood WBC count was 10,400/microliter with 90% promyelocytes. The bone marrow was hypercellular with 88% promyelocytes. Disseminated intravascular coagulation was recognized. The patient was diagnosed as having acute promyelocytic leukemia and was treated with daily oral administration of all-trans retionic acid (ATRA) (45 mg/m2/day) and cytarabine (160 mg/day, intravenous drip infusion for the initial five days). The ATRA treatment induced leukemic cells to undergo mature myeloid differentiation. On day 24 after the start of treatment, the WBC count rapidly increased and acute myocardial infarction appeared, with consciousness disturbance and bilateral Babinski reflex appearing three hours later. Magnetic resonance imaging showed a fresh lacunar infarction of the right lenticular nucleus, and serum levels of IL-6 and PAI-1 were found to be elevated at the onset of infarction. Since there was a possibility that the retinoic acid syndrome (RAS) might have helped bring about the infarctions, we stopped the ATRA treatment and started administration of methyl-prednisolone (500 mg/body/day for 3 days) and gabexate mesilate. The WBC count decreased immediately and the consciousness disturbance improved. In this case, ATRA treatment might have initiated the RAS and resulted in some endothelial damage, thus causing the infarctions.  相似文献   
9.
In some severe skeletal Class III patients, mandibular setback surgery using sagittal split ramus osteotomy (SSRO) is performed to correct mandibular protrusion. However, in patients diagnosed with obstructive sleep apnea syndrome (OSAS), the risk of OSAS worsening as a result of the SSRO is very high. Maxillary advancement could reduce the degree of mandibular retropositioning and expand the skeletal framework in the pharyngeal region, leading to enlargement of the airway. However, nasal deformity is an undesirable outcome of the procedure. This case report describes a 23-year-old man with a retruded maxilla and OSAS. The maxillary retrusion was treated using Le Fort I osteotomy with an alar cinch suture and a muco-musculo-periosteal V-Y closure (ACVY). After treatment, better occlusal relationships and improvement in OSAS were observed. Thus, an ACVY could minimize nasolabial deformity.  相似文献   
10.
Immunosuppressive therapy has been employed as the initial treatment for acquired chronic pure red cell aplasia (PRCA), such as idiopathic, thymoma‐associated, or large granular lymphocyte (LGL) leukaemia‐associated PRCA, which is thought to be immune‐mediated. To explore the overall long‐term outcome following immunosuppression and to identify the risk factors for death in these disorders, we conducted nationwide surveys in Japan 2004 and 2006, and identified a total of 185 patients with acquired chronic PRCA, including 72 idiopathic, 41 thymoma‐associated and 14 LGL leukaemia‐associated cases of PRCA for whom data was available. The present study evaluated 127 patients with these three subsets of PRCA. The median overall survival has not yet been reached in idiopathic PRCA. The estimated median overall survival times in patients with thymoma‐associated and LGL leukaemia‐associated PRCA were 142·1 and 147·8 months, respectively. Twenty‐two deaths were reported, and the response to induction therapy and relapse of anaemia were found to be associated with death. The major causes of death were infection in seven patients and organ failure in another seven patients. The results suggest that maintenance therapy and the management of infectious complications are crucial for improving the prognosis of chronic PRCA.  相似文献   
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