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71.
Background
Early iron supplementation in women with sufficient reserves could provoke iron excess resulting in haemoconcentration and low infant birth weight (IBW).Aim
To clarify the influence of early iron supplementation on maternal iron status and the IBW, taking into account pre-pregnancy iron deposits.Study design
Longitudinal, prospective study.Subjects
Healthy women volunteers (n = 82) intending to become pregnant.Outcome measures
Women were grouped as a function of their pre-pregnancy (low or present) iron stores (serum ferritin (SF) < or ≥ 20 μg/L) and time of commencement of iron supplementation during pregnancy; “early” (< 20 weeks) or “late” (≥ 20 weeks). Obstetric and clinical history, smoking habit, dietary intake and iron biochemical parameters were obtained at pre-pregnancy as well as at 1st, 2nd and 3rd trimesters. Haemoglobin, MCV, SF and transferrin saturation (TS) were measured.Results
Overall, 36% of the women had low iron stores at pre-pregnancy. The mean early supplementation with iron was 140.7 mg/d and the mean of late supplementation was 99.01 mg/d. Early supplementation improves the biochemical status of the mother and does not provoke a significant increase in haemoconcentration relative to late supplementation independently of the pre-pregnancy iron levels.Supplemental iron had a positive effect on birth weight among women with pre-pregnancy low iron stores (β = 4.37; SE = 1.8; p = 0.038) and did not affect birth weight among women with present iron stores (β = − 0.008; SE = 3.03; p = 0.998).Conclusion
Early iron supplementation with doses ~ 100 mg/d improves the biochemical status of the mother independently of her pre-pregnancy iron status. Supplementation with iron improves newborn birth weight in those women who start pregnancy with iron deficiency, and makes no significant difference to those women who are not iron deficient. 相似文献72.
Axonal damage in multiple sclerosis (MS) lesions is associated with failure of fibrinolysis because of the inhibition of the plasminogen activator system. Plasma membrane receptors for tissue plasminogen activator (tPA) and plasminogen concentrate proteolytic activity on the cell surface and provide protection from inhibitors that in turn may locally enhance the fibrinolytic response. Therefore, we have investigated expression of two of these receptors in MS lesions, annexin II tetramer (AIIt) and low-density lipoprotein receptor-related protein (LRP). In acute MS lesions both AIIt and LRP were immunolocalized on macrophages and astrocytes while LRP was additionally found on neuronal cells in cortical gray matter. Western blot analysis confirmed a significant increase in AIIt in MS lesions and in a proportion of normal-appearing white matter samples, with a highly significant correlation between annexin II levels and factors associated with impeded fibrinolysis, such as plasminogen activator inhibitor-1. Immunoblotting analysis of plasmin(ogen) revealed increased levels of lysine-plasminogen in samples expressing high AIIt protein levels. Our results suggest that limited availability of tPA in MS lesions because of formation of tPA-plasminogen activator inhibitor-1 complexes reduces capability of tPA receptors to generate plasmin, which further diminishes fibrinolytic capacity in active MS lesions and possibly leads to axonal damage. 相似文献
73.
Emilio Fla?o Francisco álvarez Pilar López-Fierro Blanca E. Razquin Alberto J. Villena Agustín G. Zapata 《Clinical & developmental immunology》1996,5(1):17-24
We present an enzyme- and immuno-cytochemical, and ultrastructural characterization of
trout thymic nurse cells (TNCs). Our data suggest that isolated trout thymic multicellular
complexes are epithelial cells with acidic compartments that may be involved in the processing
of antigens and in the generation of the MHC-II proteins that these cell express, and
also that isolated TNCs are the In Vitro equivalent of the pale and intermediate electronlucent
epithelial cells located in the inner zone of the trout thymus, constituting indirect
evidence of the phylogenetical relationships of the inner zone of the teleost thymus with
the thymic cortex of higher vertebrates. 相似文献
74.
Berge-Lefranc JL; Jay P; Massacrier A; Cau P; Mattei MG; Bauer S; Marsollier C; Berta P; Fontes M 《Human molecular genetics》1996,5(10):1637-1641
While constructing a cDNA library of human embryos, we have isolated a
clone homologous to jumonji, a mouse gene required for neural tube
formation. We have determined the complete coding sequence of the human
homologue (JMJ) and deduced the amino acid sequence of the putative
protein. We show here that human and mouse jumonji putative proteins are
homologous and present 90% identity. During human embryogenesis, JMJ mRNAs
are predominantly expressed in neurons and particularly in dorsal root
ganglion cells. They are also expressed in neurons of human adult cerebral
cortex. In view of these observations, we propose JMJ as a candidate gene
for developmental defects of the central nervous system in the human. The
human JMJ gene maps at position 6p24-6p23.
相似文献
75.
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77.
Rondón C Campo P Togias A Fokkens WJ Durham SR Powe DG Mullol J Blanca M 《The Journal of allergy and clinical immunology》2012,129(6):1460-1467
Local allergic rhinitis (LAR) is a localized nasal allergic response in the absence of systemic atopy characterized by local production of specific IgE (sIgE) antibodies, a T(H)2 pattern of mucosal cell infiltration during natural exposure to aeroallergens, and a positive nasal allergen provocation test response with release of inflammatory mediators (tryptase and eosinophil cationic protein). Although the prevalence remains to be established, a number of patients previously given a diagnosis of nonallergic rhinitis or idiopathic rhinitis are now being classified as having LAR. Culprit allergens responsible include house dust mite, grass and olive pollens, and many others. For the diagnosis of LAR, neither skin prick testing nor determination of the presence of serum sIgE antibodies is useful, and a nasal allergen provocation test is needed to identify the culprit allergen or allergens. In a certain proportion of cases, local sIgE can be detected, and conjunctivitis, asthma, or both can be associated. Whether patients with LAR will have systemic atopy in the future is a matter of debate. Further studies are needed for examine the prevalence of this phenomenon in different areas, to improve the diagnostic methods to better identify these patients, and to develop therapeutic approaches, including the use of immunotherapy. 相似文献
78.
Cho MH Castaldi PJ Wan ES Siedlinski M Hersh CP Demeo DL Himes BE Sylvia JS Klanderman BJ Ziniti JP Lange C Litonjua AA Sparrow D Regan EA Make BJ Hokanson JE Murray T Hetmanski JB Pillai SG Kong X Anderson WH Tal-Singer R Lomas DA Coxson HO Edwards LD MacNee W Vestbo J Yates JC Agusti A Calverley PM Celli B Crim C Rennard S Wouters E Bakke P Gulsvik A Crapo JD Beaty TH Silverman EK;ICGN Investigators;ECLIPSE Investigators;COPDGene Investigators 《Human molecular genetics》2012,21(4):947-957
The genetic risk factors for chronic obstructive pulmonary disease (COPD) are still largely unknown. To date, genome-wide association studies (GWASs) of limited size have identified several novel risk loci for COPD at CHRNA3/CHRNA5/IREB2, HHIP and FAM13A; additional loci may be identified through larger studies. We performed a GWAS using a total of 3499 cases and 1922 control subjects from four cohorts: the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE); the Normative Aging Study (NAS) and National Emphysema Treatment Trial (NETT); Bergen, Norway (GenKOLS); and the COPDGene study. Genotyping was performed on Illumina platforms with additional markers imputed using 1000 Genomes data; results were summarized using fixed-effect meta-analysis. We identified a new genome-wide significant locus on chromosome 19q13 (rs7937, OR = 0.74, P = 2.9 × 10(-9)). Genotyping this single nucleotide polymorphism (SNP) and another nearby SNP in linkage disequilibrium (rs2604894) in 2859 subjects from the family-based International COPD Genetics Network study (ICGN) demonstrated supportive evidence for association for COPD (P = 0.28 and 0.11 for rs7937 and rs2604894), pre-bronchodilator FEV(1) (P = 0.08 and 0.04) and severe (GOLD 3&4) COPD (P = 0.09 and 0.017). This region includes RAB4B, EGLN2, MIA and CYP2A6, and has previously been identified in association with cigarette smoking behavior. 相似文献
79.
Objective. The aims of this study were to examine the internal structure of the Spanish version of the Chronic Pain Acceptance Questionnaire and present new empirical evidence regarding its validity. Design and Methods. A sample of 315 chronic pain patients attending a pain clinic completed a battery of instruments to assess pain acceptance, general psychological acceptance, depression, anxiety, pain intensity, functional impairment, and current functioning. Results. Confirmatory factor analysis supported the validity of a 20‐item version with two subscales corresponding to two independent factors: Activity Engagement and Pain Willingness. Structural Equation Modelling showed that the association between pain intensity and anxiety and depression was fully mediated by Activity Engagement which partially mediated the association between pain intensity and functioning. Pain Willingness partially mediated the influence of pain intensity on functional impairment. Conclusions. These findings indicate the differential influence of both components on adjustment to chronic pain. 相似文献
80.
Bone morphogenetic protein-2/4 signalling pathway components are expressed in the human thymus and inhibit early T-cell development 下载免费PDF全文
Cejalvo T Sacedón R Hernández-López C Diez B Gutierrez-Frías C Valencia J Zapata AG Varas A Vicente A 《Immunology》2007,121(1):94-104
T-cell differentiation is driven by a complex network of signals mainly derived from the thymic epithelium. In this study we demonstrate in the human thymus that cortical epithelial cells produce bone morphogenetic protein 2 (BMP2) and BMP4 and that both thymocytes and thymic epithelium express all the molecular machinery required for a response to these proteins. BMP receptors, BMPRIA and BMPRII, are mainly expressed by cortical thymocytes while BMPRIB is expressed in the majority of the human thymocytes. Some thymic epithelial cells from cortical and medullary areas express BMP receptors, being also cell targets for in vivo BMP2/4 signalling. The treatment with BMP4 of chimeric human-mouse fetal thymic organ cultures seeded with CD34+ human thymic progenitors results in reduced cell recovery and inhibition of the differentiation of human thymocytes from CD4- CD8- to CD4+ CD8+ cell stages. These results support a role for BMP2/4 signalling in human T-cell differentiation. 相似文献