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211.
Representative levels of serum micronutrients specifically, beta-carotene and vitamins A and E, were studied in symptomatic human immunodeficiency virus (HIV)-infected children. The nutritional status of 23 symptomatic African-American and Hispanic HIV-infected children were compared with an appropriate control group comprised of 36 uninfected children matched for age and sex, using body mass index. Serum beta-carotene and vitamin A and E levels were randomly determined on 15 of the infected children. Beta-carotene concentration was 4.9-fold reduced in symptomatic HIV-infected children when compared with the control group. There was a 6.5-fold decrease in the serum level for children without acquired immunodeficiency syndrome (AIDS) and a 13-fold reduction in children with AIDS. No differences in the mean values for serum vitamins A and E were observed in the groups studied. Although the nutritional status of the symptomatic HIV-infected children was not different from that of the control population, their serum beta-carotene levels were profoundly deficient. This finding may have immunologic and clinical implications for children with rapidly progressing HIV disease.  相似文献   
212.
The mucosal immune system has evolved alongside, but separate, from the general systemic immune system. As a major consequence of this dichotomy, only immune responses initiated in mucosal inductive sites can result in effective immunity in mucosal tissues themselves. Oral tolerance, as usually assessed as orally-induced systemic unresponsiveness, contributes to mucosal homoeostasis by preventing unwanted immune reactions to food or environmental antigens. It is now established that tolerance can also be induced by the nasal route and mucosally-induced tolerance is being actively investigated for immune therapy against a number of diseases. Nontoxic derivatives of cholera toxin and the heat labile toxin of Escherichia coli as well as chimeric enterotoxins have been developed. These molecules retain the mucosal adjuvant activity of native enterotoxins and are effective at inducing targeted Th1 or Th2- type immune responses. Mucosal delivery of cytokines as adjuvants represents a safer alternative to parenteral cytokine injection. Nasally administered cytokines such as IL-1 and IL-12 or chemokines including RANTES, lymphotactin, MIP-1 beta, all act as mucosal adjuvants for co-administered antigens. Each of these cytokines promote specific pattern of CD4(+) T helper cell cytokine responses that could be exploited for targeted immune therapy. Although GALT and NALT are both parts of the Common Mucosal Immune System, there are major differences between orally and nasally induced immune responses. Nasal vaccines more effectively promote protective immunity in the genitourinary tract than do oral vaccines. In addition, aging affects mucosal tolerance or immunity in GALT more than is seen in NALT. Therapeutic manipulation of mucosal immunity involves regulation of CD4(+) T cell cytokine responses and thus, should require a careful examination of the host status, including the occurrence of inflammatory bowel diseases.  相似文献   
213.
Few studies have been conducted on the effects of air pollution on patients with chronic obstructive pulmonary disease (COPD). During a 14-mo period, 39 Parisian adults with severe COPD were monitored by their physicians. Daily levels of 4 air pollutants were provided by an urban air-quality network. Exacerbation of COPD was associated only with ozone (O3) (odds ratio [OR] = 1.44 for a 10-microg/m3 increase in O3; 95% confidence interval [CI] = 1.14, 1.82), with a lag of 2-3 days. The effect of O3 was greater in patients whose carbon dioxide pressure (PaCO2) was higher than 43 mm Hg (OR = 1.83; 95% CI = 1.36, 2.47) vs. those with a lower PaCO2 (OR = 1.26; 95% CI = 0.90, 1.77). The effect of O3 was unchanged, regardless of the maintenance medications used. The only air pollutant to which patients with severe COPD were particularly sensitive was O3.  相似文献   
214.
The aim of this study was to determine whether the detection of CTC in the apheresis product contribute significantly to treatment failure of patients with high-risk breast carcinoma treated with high-dose chemotherapy (HDC) and stem cell transplantation (SCT). Patients were with stage II and III adenocarcinoma of the breast with > or = 10 axillary lymph nodes affected after primary surgery (> or = 10 N+) who had received HDC with SCT. We analyzed retrospectively the presence of CTC as assessed by immunocytochemistry (ICC) in the apheresis products obtained after standard adjuvant chemotherapy. We compared the clinical outcome of patients who received HDC and SCT with or without CTC-positive apheresis. One hundred and twenty-seven apheresis products samples were obtained from 51 patients. Fourteen (27.4%) of these samples were CTC positive. After a median follow-up of 4.6 years, 20 patients have relapsed, 14 died from progression of their disease and 30 patients remain alive and free of progression. For the whole group of patients the 5 year probabilities of DFS and OS were 60% (IC 95%, 47-75%) and 71% (IC 95%, 55-83%), respectively. However, the 5 year probabilities of DFS were 23% (IC 95%, 0-46) and 75% (IC 95%, 60-89) for patients with CTC positive and negative, respectively. The 5 year probabilities of OS were 42% (IC 95%, 15-68) and 83% (IC 95%, 70-95) for patients with CTC positive and negative, respectively. Both univariate and multivariate analysis showed that the presence of CTC in the apheresis product was the only prognostic factor associated with a higher incidence of clinically overt disease relapse (P = 0.002) and shorter survival (P = 0.003). The presence of cytokeratin-positive metastatic cells in the apheresis product increases the risk of relapse after HDC and SCT in patients with stage II and III adenocarcinoma of the breast with > or = 10 N+.  相似文献   
215.
Human dermo‐epidermal skin equivalents (DE) comprising in vitro expanded autologous keratinocytes and fibroblasts are a good option for massive burn treatment. However, the lengthy expansion time required to obtain sufficient surface to cover an extensive burn together with the challenging surgical procedure limits their clinical use. The integration of DE and biodegradable scaffolds has been proposed in an effort to enhance their mechanical properties. Here, it is shown that poly(hydroxybutyrate) electrospun scaffolds (PHB) present good biocompatibility both in vitro and in vivo and are superior to poly‐ε‐caprolactone electrospun scaffolds as a substrate for skin reconstruction. Implantation of PHB scaffolds in healthy rats polarized macrophages to an M2‐type that promoted constructive in vivo remodelling. Moreover, implantation of DE‐PHB composites in a NOD/SCID mouse xenograft model resulted in engraftment accompanied by an increase in angiogenesis that favoured the survival of the human graft. Thus, PHB scaffolds are an attractive substrate for further exploration in skin reconstruction procedures, probably due in part to their greater angiogenic and M2 macrophage polarization properties. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
216.
217.
We report on three related Congolese popliteal pterygium syndrome (PPS) patients concordant only for the skinfold over the toenail. Mutation analysis revealed that the three affected individuals carried a heterozygous missense mutation in the Exon 4, NM_006147.2:c.250C>T; p.Arg84Cys. This is the first molecularly confirmed PPS family from central Africa.  相似文献   
218.
BACKGROUND: Effects of mobilization regimen on the composition of leukapheresis products (LPs) and on hematopoietic reconstitution after autologous peripheral blood progenitor cell transplantation (PBPCT) are not well known. STUDY DESIGN AND METHODS: The effects of three different mobilization regimens--stem cell factor (SCF) plus granulocyte colony stimulating factor (G-CSF) plus cyclophosphamide (CCP), G-CSF alone, and G-CSF plus CCP--on the composition of LPs from patients with nonhematologic PBPC malignancies compared to LPs from G-CSF-mobilized healthy donors and normal marrow (BM) samples were analyzed. The impact of LP composition on both short- and long-term engraftment after autologous PBPCT was also evaluated. RESULTS: The most effective regimen for mobilization of CD34+ hematopoietic progenitor cells (HPCs) into peripheral blood was SCF, G-CSF, and CCP, providing the highest numbers of all CD34+ HPCs subsets analyzed. Patients mobilized with SCF plus G-CSF plus CCP showed the highest numbers of neutrophils and monocytes, whereas the highest numbers of lymphocytes and NK cells were observed in LPs from G-CSF-mobilized patients. The overall number of CD34+ HPCs was the strongest factor for predicting recovery of platelets, whereas the number of myelomonocytic-committed CD34+ precursors was the most powerful independent prognostic factor for WBC and neutrophil recovery. The overall number of CD4+ T cells returned showed an independent prognostic value for predicting the occurrence of infections, during the first year after transplant. CONCLUSIONS: The use of different mobilization regimens modifies the overall number of CD34+ HPCs obtained during leukapheresis procedures, and also affects both the absolute and the relative composition of the LPs in different CD34+ and CD34- cell subsets.  相似文献   
219.
220.
The potential of poly(lactic-co-glycolic) acid (PLGA) microparticles as carriers for vascular endothelial growth factor (VEGF) has been demonstrated in a previous study by our group, where we found improved angiogenesis and heart remodeling in a rat myocardial infarction model (Formiga et al., 2010). However, the observed accumulation of macrophages around the injection site suggested that the efficacy of treatment could be reduced due to particle phagocytosis.  相似文献   
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