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31.
BACKGROUND: Despite ongoing progresses of IVF techniques, biomarkers predicting their outcome prior to IVF initiation are lacking. We investigated whether serum levels of the stress-inducible soluble major histocompatibility complex Class I chain-related molecule, MICA, (sMIC), a regulator of cellular immunity, can be predictive of implantation or pregnancy failure after IVF. METHODS: sMIC serum levels, evaluated during the follicular phase of the cycle preceding in vitro fertilization, in a cohort of 170 infertile women with 22.3% IVF success rate were analyzed in association with implantation/pregnancy failure or live birth outcomes after IVF. RESULTS: sMIC serum levels, detected in 38% of all women undergoing IVF, were shown to be predictive both of implantation failure (> or = 2.45 ng/ml cut off, odds ratio (OR) = 4.6; 95% confidence interval (CI) = 1.08 - 19.79; P = 0.031) and successful pregnancy (< 2.45 ng/ml, OR = 13.8; 95% CI = 2.03-118.3; P = 0.002). When successful implantation occurred, sMIC levels > 3.2 ng/ml were predictive of spontaneous abortion (OR = 35; 95% CI = 1.74-703; P = 0.026). CONCLUSIONS: sMIC is thus to be considered as a novel blood biomarker which, when quantified prior to initiation of IVF, anticipates chances for infertile women to give birth to a viable baby. Considering medical and psychological cost of IVF, this non-invasive assay may thus contribute to better counseling, treatment and care of infertile couples prior to IVF.  相似文献   
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Patients with T-cell acute lymphoblastic leukemias (T-ALLs) within the Leucemies Aigues Lymphoblastiques de l'Adulte-94 (LALA-94) prospective trial were treated with a 4-drug per 4-week induction, with intermediate-dose cytarabine and mitoxantrone salvage treatment for patients not achieving complete remission (CR) in 1 course. Only the latter received allografts, if possible, thus providing an informative setting for assessing early response. Representative patients with T-ALL (91 patients) were classified into surface T-cell receptor (TCR)-expressing T-ALL patients (TCRalphabeta+ or TCRgammadelta+), pre-alphabeta T-ALL patients (cTCRbeta+, TCR-), and immature (IM) cTCRbeta-, TCR- T-ALL patients; 81 patients underwent genotyping for SIL-TAL1, CALM-AF10, HOX11, and HOX11L2. Overall, CR was obtained in 81 (89%) patients; relapse rate was 62% at 4 years and overall survival (OS) rate was 38%. CR rate was significantly lower in IM T-ALL patients after 1 course (45% vs 87%; P < .001) and after salvage (74% vs 97%; P = .002), with the latter inducing a higher rate of CR (9 [64%] of 14) than initial induction. Once CR was obtained, cumulative relapse rates were similar for IM, pre-alphabeta, and TCR+ T-ALL patients (P = .51), but were higher in HOX11L2 (83%) and SIL-TAL1 (82%) T-ALL patients compared with other genetic subgroups (48%; P = .05). This was associated with an inferior OS for HOX11L2 T-ALLs (13% vs 47% in HOX11L2-T-ALLs; P = .009). The majority of patients with HOX11 T-ALL underwent allografting, predominantly in second CR, but were not associated with a superior OS. Both TCR and genotypic stratification can therefore contribute to risk-adapted management of adult T-ALLs.  相似文献   
34.
In chronic myelogenous leukemia (CML) imatinib mesylate has been shown to selectively inhibit the tyrosine kinase domain of the oncogenic bcr-abl fusion protein. Using this agent alone high rates of cytogenetic responses were recorded. However, several mechanisms of resistance have been described. In vitro studies examining the effects of imatinib mesylate plus cytarabine have shown synergistic antiproliferative effects of this combination. Thus, the CML French Group decided to perform a phase 2 trial testing a combination of imatinib mesylate and low-dose cytarabine in 30 previously untreated patients in chronic phase. Treatment was administered on 28-day cycles. Patients were treated continuously with imatinib mesylate orally at a dose of 400 mg daily. Cytarabine was given on days 15 to 28 of each cycle at an initial dose of 20 mg/m2/d via subcutaneous injection. Adverse events were frequently observed with grade 3 or 4 hematologic toxicities and nonhematologic toxicities in 53% (n = 16) and 23% (n = 7) of patients, respectively. The cumulative incidence of complete cytogenetic response (CCR) at 12 months was 83% and at 6 months 100% of the patients achieved complete hematologic response (CHR). We concluded that the combination was safe and promising given the rates of response.  相似文献   
35.
Enforced expression of c-mpl in embryonic stem (ES) cells inactivated for this gene results in protein expression in all the ES cell progeny, producing cells that do not belong to the megakaryocytic lineage and are responsive to PEG-rhuMGDF, a truncated form of human thrombopoietin (TPO) conjugated to polyethylene glycol. These include a primitive cell called BL-CFC, thought to represent the equivalent of the hemangioblast, and all myeloid progenitor cells. In this model, PEG-rhuMGDF was able to potentiate the stimulating effects of other growth factors, including vascular endothelial growth factor, on BL-CFC and a combination of cytokines on the growth of granulocyte macrophage-colony-forming units. The importance of the C-terminal domain of Mpl and of mitogen-activated protein kinase (MAPK) activation in TPO-dependent megakaryocytic differentiation has been well studied in vitro. Here, the role of this domain and the involvement of MAPK in upstream and nonmegakaryocytic cells are examined by using 2 truncated mutants of Mpl (Delta34, deletion of residues 71 to 121 in the C-terminal domain; and Delta3, deletion of residues 71-94) and specific inhibitors of the MAPK pathway. The 2 deleted regions support different functions, mediated by different signals. Residues 71 to 121 were required for PEG-rhuMGDF-dependent growth of BL-CFC, for megakaryocytic and other myeloid progenitors, and for megakaryocyte polyploidization. These responses were mediated by the ERK1-ERK2 MAPK pathway. In contrast, the only function of the sequence comprising residues 71 to 94 was to mediate the synergistic effects of PEG-rhuMGDF with other hematopoietic growth factors. This function is not mediated by MAPK activation.  相似文献   
36.
Glucocorticoids are important hormones in the regulation of metabolic homeostasis. We infused normal rats with dexamethasone given intracerebroventricularly (i.c.v.) for 3 days. This resulted in hyperphagia, hyperinsulinemia, and marked insulin resistance. Similar metabolic defects were observed following i.c.v. infusion of neuropeptide Y (NPY) in normal rats. As central dexamethasone infusion enhanced NPY content in the arcuate nucleus, it suggested that its metabolic effects are mediated by NPY. Moreover, due to the lack of effects observed in vagotomized animals, activation of the parasympathetic nervous system by central dexamethasone infusion is proposed. Glucocorticoid action is known to involve prereceptor metabolism by enzymes such as 11beta-HSD-1 that converts inactive into active glucocorticoids. Mice overexpressing 11beta-HSD-1 in adipose tissue were shown to be obese and insulin resistant. We recently observed that adipose tissue 11beta-HSD-1 mRNA expression is increased at the onset of high-fat diet-induced obesity and positively correlated with the degree of hyperglycemia. In human obesity, increased adipose tissue 11beta-HSD-1 expression and activity were also reported. Resistin is a new adipose tissue-secreted hormone shown to play a role in glucose homeostasis by increasing hepatic glucose production and inhibiting muscle and adipose tissue glucose utilization. We observed increased adipose tissue resistin expression in the early phase of high-fat diet-induced obesity as well as decreased resistin expression in response to leptin. A positive correlation between glycemia and adipose tissue resistin expression further suggested a role of this hormone in the development of insulin resistance. The melanocortin system is another important player in the regulation of energy balance. Peripheral administration of a melanocortin agonist decreased food intake and body weight and favored lipid oxidation, effects that were more marked in obese than in lean rats. It is proposed that both resistin and melanocortin agonists may influence adipose tissue 11beta-HSD-1, thereby decreasing or enhancing glucose metabolism.  相似文献   
37.
BACKGROUND: Steatosis is common in hepatitis C virus (HCV)-infected patients and likely accelerates fibrosis progression. Leptin, the peptide product of the obesity gene (ob), has been implicated in hepatic fibrogenesis; circulating levels of leptin correlate with body fat mass. The objective of the present study was to determine the clinical and histological correlates of serum leptin in HCV-infected patients, and to determine its utility in predicting liver histological lesions. PATIENTS AND METHODS: In 62 patients with chronic HCV, serum leptin was measured using a commercially available immunoassay. Associations between leptin, metabolic parameters, and severe hepatic fibrosis (stages 2 to 4) and steatosis (30% or greater) were determined. The utility of leptin in predicting liver histology was determined using receiver operating characteristic (ROC) curves. RESULTS: The median body mass index (BMI) was 23.2 kg/m2 (range 17.7 kg/m2 to 35.6 kg/m2); 16% of patients (n=10) had HCV genotype 3. Severe fibrosis and steatosis were present in 23% and 13% of patients, respectively. Leptin was strongly correlated with the BMI, and its levels were higher in women. BMI-corrected leptin levels were not independently associated with severe fibrosis but were significantly associated with steatosis (OR of 1.07; 95% CI 1.01 to 1.04). On it own, leptin was poorly predictive of severe steatosis (area under the ROC curve was 0.64; 95% CI 0.42 to 0.87). However, its accuracy improved with the addition of HCV genotype (area under the ROC curve was 0.86; 95% CI 0.72 to 1.00; P=0.07). CONCLUSIONS: As observed in the non-HCV setting, serum leptin correlates with BMI; higher leptin levels are found in women than men with chronic HCV. Serum leptin is a poor predictor of HCV-related fibrosis but may play a role in predicting steatosis when combined with HCV genotype.  相似文献   
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Primary immunodeficiencies are intrinsic defects in the immune system that result in a predisposition to infection and are frequently accompanied by a propensity to autoimmunity and/or immunedysregulation. Primary immunodeficiencies can be divided into innate immunodeficiencies, phagocytic deficiencies, complement deficiencies, disorders of T cells and B cells (combined immunodeficiencies), antibody deficiencies and immunodeficiencies associated with syndromes. Diseases of immune dysregulation and autoinflammatory disorder are many times also included although the immunodeficiency in these disorders are often secondary to the autoimmunity or immune dysregulation and/or secondary immunosuppression used to control these disorders. Congenital primary immunodeficiencies typically manifest early in life although delayed onset are increasingly recognized. The early diagnosis of congenital immunodeficiencies is essential for optimal management and improved outcomes. In this International Consensus (ICON) document, we provide the salient features of the most common congenital immunodeficiencies.  相似文献   
40.
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