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991.
BACKGROUND: Here we evaluate the results of high-dose chemotherapy and autologous stem-cell transplantation (HDC/ASCT) in 114 patients included in the GEL/TAMO registry between January 1990 and December 1999 with diffuse large B-cell lymphoma who failed to achieve complete remission (CR) with front-line conventional chemotherapy. PATIENTS AND METHODS: Sixty-eight per cent had a partial response (PR) and 32% failed to respond to front-line therapy. At transplant, 35% were chemoresistant and 29% had two to three adjusted International Prognostic Index (a-IPI) risk factors. RESULTS: After HDC/ASCT, 57 (54%) of 105 patients evaluable for response achieved a CR, 16 (15%) a PR and 32 (30%) failed. Nine patients were not assessed for response because of early death due to toxicity. With a median follow-up of 29 months for alive patients, the survival at 5 years is 43%, with a disease-free survival for complete responders of 63%. The lethal toxicity was 8%. Multivariate analysis revealed a-IPI and chemoresistance to be predicting factors. CONCLUSIONS: Our results show that one-third of patients who do not obtain a CR to front-line chemotherapy may be cured of their disease with HDC/ASCT. However, most chemoresistant patients pretransplant failed this therapy. For this population, as well as for those who presented with adverse factors of the a-IPI, pretransplant novel therapeutic modalities need to be tested.  相似文献   
992.
In the present study, we searched for genes highly expressed in placenta and that could contribute to the establishment and maintenance of a malignant phenotype in different types of tumours, and in astrocytomas in particular. We employed a strategy based on the integration of in silico data from previously generated massively parallel signature sequencing and public serial analysis of gene expression databases. Among 12 selected genes, CD99 exhibited the highest relative mRNA expression in GBM compared to non-neoplastic brain tissues. In a larger cohort of astrocytic tumours, we further demonstrated increased CD99 expression in all malignant grades, with GBMs showing the highest values. These findings were confirmed at the protein level by Western blotting and immunohistochemistry. Additionally, we demonstrated the CD99 localisation profile in astrocytic tumours. Interestingly, CD99 expression was confined to the cytoplasm or membrane in more malignant astrocytomas, in contrast to non-neoplastic brain tissue or non-infiltrative pilocytic astrocytoma, which showed no obvious staining in these structures. Comparison of three GBM cell lines revealed higher CD99 expression at the membrane and higher migratory capacity in the A172 and U87MG lines, but lower CD99 expression and no migratory ability in the T98 line. Knocking down CD99 expression by siRNA decreased significantly the migration of both cell lines. These integrated CD99 gene and protein expression results suggest that CD99 expression in astrocytomas of different malignant grades might contribute to the infiltrative ability and support the importance of CD99 as a potential target to reduce infiltrative astrocytoma capacity in migration and invasion.  相似文献   
993.
Health literacy is related to a number of health status variables and has been associated with medication adherence in persons treated for HIV infection. Currently-available measures of health literacy require lengthy administration or have content or format limitations. In this paper we report the preliminary development and validation of a brief computer-administered health literacy test that includes content focused on medication adherence as well as questions based on a video simulation of an HIV-related clinical encounter. The measure shows significant relations with other measures of health literacy, HIV-related knowledge, and electronically-measured medication adherence. We also present receiver operating characteristic analyses that provide estimates of various scores’ sensitivities and specificities so that the HIV-Related Health Literacy Scale can be used as a screening measure.  相似文献   
994.
995.
Purpose: The aim of this study is to evaluate the health of oocyte donors and explain how they regard their experience in the long-term.

Materials and methods: This is a cross-sectional study in a single fertility centre that consists of a telephone interview guided by a semi-structured questionnaire covering several aspects of reproductive health and personal experience.

Results: At the time of interview, 84 out of 121 women (69%) had children while 64 (53%) were already mothers at the time of their donation. Of the 38 women achieving a pregnancy after donation, five reported six pregnancy complications. Two out of 121 (2%) women reported being in menopause (aged 41 and 45). Twenty-three women (19%) reported gynaecological issues and eight (7%) reported fertility problems, although only four consulted a specialist. Most of women highlighted positive feelings about their donation (113, 93%) and 155 (97%) would recommend donating. Less than half (53, 44%) mentioned some negative aspects, mainly related to physical discomfort: injections (20,17%), pain (17, 14%), and side effects of ovarian stimulation (10, 8%).

Conclusion: The impact of donation on women’s life was mostly favourable, with the majority of participants reporting positive aspects and recommending donation, although some negative feelings as physical discomfort also arose. Therefore, more comfortable stimulation protocols could be developed.  相似文献   

996.
Traditional cardiovascular risk factors are associated with endothelial dysfunction. The vascular endothelium plays a key role in local vascular tone regulation and can be modulated by dietary fat. We propose to determine the chronic effect of three diets with different fat compositions on postprandial endothelial function and inflammatory biomarkers. Twenty healthy men followed three 4-week diets in a randomised cross-over design: a Western diet, rich in saturated fat (22% SFA, 12% MUFA and 0.4% alpha-linolenic acid (ALA), all fractions are % of energy); a Mediterranean diet, rich in MUFA ( < 10 % SFA, 24 % MUFA and 0.4% ALA); a low-fat diet enriched in ALA ( < 10% SFA, 12% MUFA and 2% ALA). At the end of each dietary period all subjects underwent a postprandial study. Plasma concentrations of lipid parameters, soluble intercellular cell-adhesion molecule-1, soluble vascular cell-adhesion molecule-1 (sVCAM-1), nitrates and nitrites (NOx) and endothelial function studied by laser Doppler were examined at 0, 2, 4, 6 and 8 h. The endothelium-dependent vasodilatory response was greater 4 h after the ingestion of the MUFA-rich diet than after the SFA or ALA low-fat diets (P = 0.031). The 4 h postprandial plasma sVCAM-1 levels were lower after the MUFA meals than after the ALA low-fat diet (P = 0.043). The bioavailability of NOx was higher following the MUFA diet than after the SFA and ALA low-fat diets (P = 0.027). We found no differences in the other parameters measured. Chronic ingestion of a Mediterranean diet avoids the postprandial deterioration of endothelial function associated with Westernised diets in healthy individuals.  相似文献   
997.
In the present study, the effects of retinoid metabolite administration during in vitro maturation (IVM) on oocyte maturation, parameters of in vitro fertilisation (IVF) and embryo development were examined. Varying concentrations of 9-cis retinoic acid (RA; 0, 5, 50 and 500 nm; Experiment 1) and all-trans retinol (ROH; 0, 125, 1250 and 12 500 nm; Experiment 2) were included in the maturation medium. Cumulus-oocyte complexes were matured in vitro and inseminated with frozen-thawed spermatozoa. Presumptive zygotes were cultured for 16 h to assess IVF parameters or for 7 days to assess embryo development and quality. In Experiment 1, the oocyte maturation rate to metaphase II was significantly decreased (P < 0.001), with values below 5%, in the presence of the highest concentration of RA (500 nm). However, 5 and 50 nm RA had no effect compared with control. Treatment with 5 nm RA improved the blastocyst development rate (P < 0.001). In Experiment 2, the oocyte maturation rate did not differ between 125 and 1250 nm ROH treatment groups and control. However, treatment with 12 500 nm ROH was deleterious because no matured oocytes were observed following the treatment. The penetration rate was lower in the group treated with 1250 nm ROH compared with the 125 nm ROH-treated and control groups, but the blastocyst formation rate did not differ among the three groups. In conclusion, 5 nm RA in the IVM medium significantly increased the blastocyst formation rate, suggesting that RA may play an important role during IVM.  相似文献   
998.
999.

OBJECTIVE

Peripheral blood CD34+ cells from diabetic patients demonstrate reduced vascular reparative function due to decreased proliferation and diminished migratory prowess, largely resulting from decreased nitric oxide (NO) bioavailability. The level of TGF-β, a key factor that modulates stem cell quiescence, is increased in the serum of type 2 diabetic patients. We asked whether transient TGF-β1 inhibition in CD34+ cells would improve their reparative ability.

RESEARCH DESIGN AND METHODS

To inhibit TGF-β1 protein expression, CD34+ cells were treated ex vivo with antisense phosphorodiamidate morpholino oligomers (TGF-β1-PMOs) and analyzed for cell surface CXCR4 expression, cell survival in the absence of added growth factors, SDF-1-induced migration, NO release, and in vivo retinal vascular reparative ability.

RESULTS

TGF-β1-PMO treatment of diabetic CD34+ cells resulted in increased expression of CXCR4, enhanced survival in the absence of growth factors, and increased migration and NO release as compared with cells treated with control PMO. Using a retinal ischemia reperfusion injury model in mice, we observed that recruitment of diabetic CD34+ cells to injured acellular retinal capillaries was greater after TGF-β1-PMO treatment compared with control PMO–treated cells.

CONCLUSIONS

Transient inhibition of TGF-β1 may represent a promising therapeutic strategy for restoring the reparative capacity of dysfunctional diabetic CD34+ cells.Bone marrow derived progenitor cells (BMPCs) support vascular repair postnatally by direct integration into blood vessels and by the release of paracrine factors such as vascular endothelial cell growth factor, matrix metalloproteases, and angiopoietins to the neovessels (1,2). BMPCs possess dramatic ability to revascularize areas within 6–12 h after the injury (3), accounting for total 1–12% of the endothelial cells present in blood vessels (4). Lineage negative (lin) cells from mice that express the cell surface antigens Sca-1 (Ly-6A/E) and c-kit can develop into endothelium, as can human lin cells expressing surface CD34 (1,5). Treatment with CD34+ cells presents an important therapeutic option for revascularization of ischemic vascular areas (6) and has been successful in numerous clinical trials (7,8).However, diabetes significantly impairs the vasoreparative ability of CD34+ cells. Diabetic patients with peripheral vascular disease have decreased levels of CD34+ cells and suffer poor vessel growth in response to ischemia (9); this defect is linked to reduced precursor cell function (10). The widespread vasodegeneration seen in diabetic retinopathy may be attributed to the inability of BMPCs to compensate for the increased endothelial injury associated with diabetes. In particular, the diabetic BMPCs are unable to repair retinal vasculature (11); thus, the total rate of retinal cell loss greatly exceeds the reparative function of these cells. We showed that diabetic CD34+ cells fail to revascularize areas of retinal vascular injury (11) likely due to reduced migration. Diabetic peripheral neuropathy further hampers repair due to defects of circadian release of BMPCs from the bone marrow, creating an imbalance between the demand and supply of BMPCs during the vasodegenerative stage of diabetic retinopathy (12). Pharmacological manipulation of diabetic CD34+ cells (13) can serve as an important therapeutic strategy for their use as autologous cell therapy to facilitate vascular repair.Transforming growth factor-β1 (TGF-β1) is a pleiotropic factor that regulates the balance between proliferation, differentiation, and quiescence of hematopoietic stem cells (HSCs), both as an extracellular and intracellular ligand (14,15). TGF-β1 is elevated in the serum of diabetic patients and possibly intracellularly in CD34+ cells (16). Enhanced levels of endogenous TGF-β1 have been reported in peripheral blood mononuclear cells of patients with diabetic nephropathy (17), and its increase provides a novel mechanism of cellular injury related to elevated glucose levels (18). Increased levels of TGF-β1 induce cellular senescence and growth arrest (19). Using blocking antibodies, we showed that transiently inhibiting TGF-β1 in murine HSCs promoted survival of these cells in the absence of growth factors (20).In this study, we investigated the effect of transient inhibition of endogenous TGF-β1 in peripheral blood diabetic CD34+ cells using ex vivo treatment with phosphorodiamidate morpholino oligomers (PMOs). PMOs act by stearic inhibition of protein synthesis by high affinity binding to 14–15 contiguous bases. PMOs are highly stable both intra- and extracellularly but are degraded after binding with a half-life of ∼2–4 days in cells (21). We report here that transient inhibition of TGF-β1 using TGF-β1-PMO may represent a promising therapeutic strategy for restoring vascular reparative function in dysfunctional diabetic CD34+ cells.  相似文献   
1000.
Remodeling imbalance in the elderly femoral neck can result in thin cortices and porosity predisposing to hip fracture. Hip osteoarthritis protects against intracapsular hip fracture. By secreting sclerostin, osteocytes may inhibit Wnt signaling and reduce bone formation by osteoblasts. We hypothesised that differences in osteocytic sclerostin expression might account for differences in osteonal bone‐formation activity between controls and subjects with hip fracture or hip osteoarthritis. Using specific antibody staining, we determined the osteocytic expression of sclerostin within osteons of the femoral neck cortex in bone removed from subjects undergoing surgery for hip osteoarthritis (hOA: 5 males, 5 females, 49 to 92 years of age) or hip fracture fixation (FNF: 5 males, 5 females, 73 to 87 years of age) and controls (C: 5 males, 6 females, 61 to 90 years of age). Sclerostin expression and distances of each osteocyte to the canal surface and cement line were assessed for all osteonal osteocytes in 636 unremodeled osteons chosen from fields (~0.5 mm in diameter) with at least one canal staining for alkaline phosphatase (ALP), a marker of bone formation. In adjacent sections, ALP staining was used to classify basic multicellular unit (BMUs) as quiescent or actively forming bone (ALP+). The areal densities of scl? and scl+ osteocytes (number of cells per unit area) in the BMU were inversely correlated and were strong determinants of ALP status in the BMU. In controls and hip fracture patients only, sclerostin‐negative osteocytes were closer to osteonal surfaces than positively stained cells. Osteon maturity (progress to closure) was strongly associated with the proportion of osteonal osteocytes expressing sclerostin, and sclerostin expression was the chief determinant of ALP status. hOA patients had 18% fewer osteocytes per unit bone area than controls, fewer osteocytes expressed sclerostin on average than in controls, but wide variation was seen between subjects. Thus, in most hOA patients, there was increased osteonal ALP staining and reduced sclerostin staining of osteocytes. In FNF patients, newly forming osteons were similar in this respect to hOA osteons, but with closure, there was a much sharper reduction in ALP staining that was only partly accounted for by the increased proportions of osteonal osteocytes staining positive for sclerostin. There was no evidence for a greater effect on ALP expression by osteocytes near the osteonal canal. In line with data from blocking antibody experiments, osteonal sclerostin appears to be a strong determinant of whether osteoblasts actively produce bone. In hOA, reduced sclerostin expression likely mediates increased osteoblastic activity in the intracapsular cortex. In FNF, full osteonal closure is postponed, with increased porosity, in part because the proportion of osteocytes expressing sclerostin increases sharply with osteonal maturation. © 2010 American Society for Bone and Mineral Research  相似文献   
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