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101.
Emotions and feelings are the bricks of our social life and yet we often forget that they have a significant impact on our physical wellbeing. Indeed, a growing number of studies have shown that both an imbalanced or improved emotional state can significantly influence the way our immune system responds. In this commentary, we have summarized the most recent studies on the effects of different types of emotional states on the immune system and we have also explored the effects of mood modulator approaches on the immune response. We hope this commentary will prompt scientists and clinicians to think about the therapeutic value and potential of emotions and feelings in immune-related diseases. At the same time, we think that this commentary will shed some light on the scientific truth behind the very famous expression “It's in my blood” when we talk about feelings and personality.  相似文献   
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103.
The issue of whether, in patients affected by myelodysplastic syndromes (MDS), haematological response to cytokines, particularly to recombinant human erythropoietin (rHuEpo), is a phenomenon related to the stimulation of normal haemopoietic cells or to the differentiation of cells belonging to the abnormal clone remains an open question. To assess the pattern of response to rHuEpo treatment of bone marrow (BM) cells, we evaluated in 13 low-risk MDS patients with known cytogenetic abnormalities the number of cytogenetically normal and abnormal cells by conventional cytogenetic analysis (CCA) and by a fluorescence in situ hybridization (FISH) technique, enabling the simultaneous visualization of FISH chromosomal abnormalities in morphologically and immunophenotypically identifiable BM elements. Patients responding to rHuEpo presented a lower number of abnormal metaphases at diagnosis in comparison with patients who did not respond (22.74% vs 76.23%, P = < 0.001). This was confirmed by the combined morphological FISH analysis, showing that, before treatment, BM samples from patients responding to rHuEpo had a lower proportion of both FISH abnormal erythroid (36.48% vs 66.93%, P = 0.002) and myeloid (40.76% vs 67.70%, P = 0.014) elements than unresponsive patients. After rHuEpo treatment, responding patients presented a significantly lower proportion of FISH abnormal erythroid precursors than observed before treatment (16.93%vs 36.48%, P = 0.017). Likewise, in responding patients, a significantly lower proportion of FISH abnormal erythroid elements (16.93% vs 66.30%, P < 0.001) was detected in comparison with unresponsive patients. These findings provide evidence that, in low-risk MDS patients with known cytogenetic abnormalities, response to rHuEpo may be due to the proliferation of karyotypically normal erythroid precursors, possibly representing residual normal erythroid elements.  相似文献   
104.
The effects of intraperitoneal Ehrlich ascites tumor (ET) growth on the kinetics of hemopoietic stem cells in the host bone marrow were studied using the spleen colony and the soft agar culture techniques. There is a decrease in spleen colony forming capacity of bone marrow of ET bearing mice, whereas in vitro assays of the committed macrophage granulocyte precursors, by the soft agar method, show that in the same circumstances a high yield of granulopoietic colonies can still be obtained. A shift of the CFU-c/CFU-s ratio from 15 to 36 thus occurs. Moreover, ascitic fluid from tumoral mice displays strong activity as CSF on normal mouse marrow, twice as strong as the standard mouse embryo CSF. When conditioned medium from cultures of ET cells (ET-CM) is tested, the pattern of agar colonies obtained is different from the previously obtained pattern of growth kinetics; furthermore many colonies are composed of undifferentiated cells. The hypothesis is suggested that among the variety of known CSF's, the ET-CM represents a unique factor, capable of inducing proliferation of marrow CFU-c, but only limited differentiation.  相似文献   
105.
Antibody-mediated inhibition of Plasmodium falciparum parasites in vitro reflects the potential parasite-neutralizing activity of the antibodies in vivo. In this study, immunoglobulins and P. falciparum isolates were collected from children with asymptomatic malaria in Burkina Faso. We demonstrate a significantly lower in vitro growth inhibitory activity against the P. falciparum field isolates by autologous host immunoglobulin compared with that of immunoglobulin from other individuals. To gain further insight to possible mechanisms for the diverse sensitivity observed, analyses of consecutive isolates taken 14 days apart were performed with regard to polymerase chain reaction-based genotyping and sensitivity to growth inhibition in vitro. All the asymptomatic infections were composed of multiple, genotypically distinct parasite clones, and at least one new parasite clone appeared in most of the day 14 isolates compared with the corresponding day 0 isolates. Apparently persisting parasite clones, present in both the day 0 and day 14 isolates from the same person, were also frequently observed. The day 14 isolates were more effectively inhibited by autologous day 14 immunoglobulin than by the corresponding day 0 immunoglobulin in 57% of the cases. However, the frequent presence of persisting parasite clones in asymptomatic children indicates that the parasite may develop a relative resistance to neutralizing immune responses.  相似文献   
106.
The activation of factor XI initiates the intrinsic coagulation pathway. Until recently it was believed that the main activator of factor XI is factor XIIa in conjunction with the cofactor high molecular weight kininogen on a negatively charged surface. Two recent reports have presented evidence that in a purified system factor XI is activatable by thrombin together with the soluble polyanion dextran sulfate. To assess the physiological relevance of these findings we studied the activation of factor XI in normal and factor XII-deficient plasma. We used either kaolin/cephalin or dextran sulfate as a surface for the intrinsic coagulation pathway, tissue factor to generate thrombin via the extrinsic pathway, or the addition of alpha-thrombin directly. 125I-factor XI, added to factor XI-deficient plasma at physiologic concentrations (35 nmol/L), is rapidly cleaved on incubation with kaolin. The kinetics appear to be exponential with half the maximum cleavage at 5 minutes. Similar kinetics of factor XI cleavage are seen when 40 nmol/L factor XIIa (equal to 10% of factor XII activation) is added to factor XII-deficient plasma if an activating surface is provided. Tissue factor (1:500) added to plasma did not induce cleavage of factor XI during a 90-minute incubation, although fibrin formation within 30 seconds indicated that thrombin was generated via the extrinsic pathway. Adding 1 mumol/L alpha-thrombin (equivalent to 50% prothrombin activation) directly to factor XII deficient or normal plasma (with or without kaolin/cephalin/Ca2+ or dextran sulfate) led to instantaneous fibrinogen cleavage, but again no cleavage of factor XI was observable. We conclude that in plasma surroundings factor XI is not activated by thrombin, and that proposals of thrombin initiation of the intrinsic coagulation cascade are not supportable.  相似文献   
107.
Of the > 50 different genetic variants of human serum albumin (alloalbumins) that have been characterized by amino acid or DNA sequence analysis, almost half have been identified in Italy through a long-term electrophoretic survey of serum. Previously we have reported structural studies of 11 Italian alloalbumins with point mutations, 2 different carboxyl-terminal variants, and 1 case of analbuminemia in an Italian family. This article describes confirmation by DNA sequencing of mutations previously inferred from protein sequencing of 4 of the above alloalbumins; it also reports the mutations identified by protein and DNA sequence analysis of 4 other Italian alloalbumins not previously recorded: albumin Larino, His3-->Tyr; Tradate-2 (protein sequencing only), Lys225-->Gln; Caserta, Lys276-->Asn; and Bazzano, a carboxyl-terminal variant. The first 3 have point mutations that produce a single amino acid substitution, but a nucleotide deletion causes a frameshift and an altered and truncated carboxyl-terminal sequence in albumin Bazzano. In these 4 instances the expression of the alloalbumin is variable, ranging from 10% to 70% of the total albumiN, in contrast to the usual 50% each for the normal and mutant albumin. The distribution of point mutations in the albumin gene is nonrandom; most of the 47 reported point substitutions involve charged amino acid residues on the surface of the molecule that are not concerned with ligand-binding sites.  相似文献   
108.
BACKGROUND: Some patients with cryoglobulinemic syndrome (CS) develop frank non-Hodgkin lymphoma (NHL), but the incidence and timing of this event are still poorly defined. METHODS: A retrospective multicenter study was performed of hepatitis C virus-positive patients with CS observed in 11 Italian centers belonging to the Italian Group for the Study of Cryoglobulinemia. RESULTS: The inclusion criteria were satisfied by 1,255 patients. During a cumulative follow-up of 8,928 patient-years, 59 cases of NHL were diagnosed, for an estimated rate of 660.8 new cases per 100,000 patient-years with 224.1 new cases of aggressive NHL subtypes per 100,000 patient-years. More than 90% of the patients developing NHLs had type II cryoglobulins. The NHLs were classified as nonaggressive in 31 cases (53%), aggressive in 20 (34%), and mucosa-associated lymphoid tissue lymphomas in 6 (10%); 2 cases were unclassifiable. The median time from the diagnosis of CS to the clinical onset of NHL was 6.26 years (range, 0.81-24 years). The clinical course and response to chemotherapy in the patients with CS who had NHL were similar to those usually described in patients with NHL without CS; the course of the CS only marginally benefited from chemotherapy. CONCLUSIONS: The overall risk of NHL in patients with CS is about 35 times higher than in the general population (12 times higher if nonaggressive lymphomas are excluded). The presence of CS did not significantly affect the treatment of newly diagnosed lymphomas.  相似文献   
109.
The PRV-1 gene has been proposed as a marker of polycythaemia vera (PV). PRV-1 and NB1 are alleles of the polymorphic gene CD177, which belongs to the Ly-6/uPAR superfamily, and their coding regions differ at only four nucleotides. We studied neutrophil CD177 mRNA levels in normal subjects and in 235 patients with Ph-negative chronic myeloproliferative disorders (CMD), including PV, essential thrombocythaemia and myelofibrosis with myeloid metaplasia. Additional disease states were investigated for comparison. Highly variable neutrophil CD177 mRNA levels were observed in normal individuals. Neutrophils isolated from the bone marrow, or from peripheral blood following granulocyte colony-stimulating factor administration showed markedly higher CD177 expression than circulating granulocytes on steady state. Increased neutrophil CD177 mRNA levels were detected in all CMD. Elevated values were also found in reactive conditions and in disorders such as chronic myeloid leukaemia and myelodysplastic syndromes. In the differential diagnosis between PV and secondary erythrocytosis, the assay sensitivity was 68% while its specificity was 60%. These findings indicate that an elevated neutrophil CD177 mRNA level is not a specific marker for the diagnosis of PV nor for that of CMD. From a clinical viewpoint, neutrophil CD177 mRNA overexpression is rather a marker of abnormal neutrophil production and/or release in patients with CMD.  相似文献   
110.
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