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51.
Background: Fabry disease is an X linked lysosomal storage disease caused by deficiency of the lysosomal enzyme α-galactosidase A. This leads to accumulation of globotriaosylceramide in nearly all tissues, including the blood vessels, kidney, myocardium, and nervous system. Symptoms often begin in childhood and include acroparaesthesia, with burning or tingling pain that spreads from the extremities to more proximal sites.

Aims: This study set out to evaluate pain and its influence on quality of life in patients with Fabry disease receiving enzyme replacement therapy (ERT) with agalsidase alfa.

Methods: Data were obtained from the Fabry Outcome Survey. Pain was measured using the Brief Pain Inventory (BPI), and health-related quality of life (HRQoL) was documented with the European Quality of Life Questionnaire (EQ-5D).

Results: The mean (SD) score for "pain at its worst" on the BPI prior to ERT was 5.1 (2.7). One year after commencement of ERT, this had improved by 0.5, and improved by a further 0.6 after 2 years (p<0.05). Similar statistically significant improvements were seen for "pain on average" and "pain now" after 2 years of ERT. The mean HRQoL utility score prior to ERT was 0.66 (0.32). After 12 months of treatment with agalsidase alfa, this had improved to 0.74 (0.26; p<0.05); this improvement was maintained after 2 years.

Conclusions: ERT with agalsidase alfa significantly reduces pain and improves quality of life in patients with Fabry disease.

  相似文献   
52.
The number of copies of CTG trinucleotide repeats in the myotonic dystrophy gene correlates to a certain degree with the clinical symptoms in the patient. Routine molecular analysis of myotonic dystrophy is performed on peripheral blood cells, detecting the size of the expansion in leukocytes. However, in some cases somatic mosaicism is responsible for the presence of differently sized myotonic dystrophy alleles in different tissues of the same affected individual, complicating diagnosis and prognosis. Here we report two cases in which the correlation between molecular and clinical analysis performed with standard procedures posed some interpretative problems. The first individual was affected by an atypical clinical picture of myotonic dystrophy, the severity of which was not correlated with the low number of triplet repeats detected in his leukocyte DNA. The second case illustrates a prognostic problem in the presence of a low degree expansion in leukocytes. These examples outline the limits of standard molecular and clinical analysis in myotonic dystrophy.  相似文献   
53.
The encounter of NK cells with dendritic cells (DC) undergoing maturation may result in the induction of NK cell proliferation. Whether such proliferation involves most NK cells or just a subset has yet to be determined. In the present study we analyzed the nature of such proliferating NK cells by combining carboxyfluorescein succinimidyl ester staining and double-fluorescence cytofluorimetric analysis. Freshly isolated peripheral blood NK cells cultured with LPS and immature DC underwent proliferation; however, proliferating cells were confined to a minor NK cell subset. This subset is characterized by the CD56(bright)CD16(-)NKG2A(+)KIR(-) surface phenotype (KIR, killer Ig-like receptor). This was further confirmed by the fact that, after cell sorting, only the CD56(bright) NK cells were able to proliferate in response to the DC stimulus, whereas the CD56(dull) were not. We also provide evidence that the CD56(bright) subset is the main source of IFN-gamma-producing NK cells, upon interaction with DC. The CD56(bright)CD16(-) NK cells express a panel of surface molecules including CD62L, CCR7 and CXCR3 that may allow their homing either to secondary lymphoid compartments or to inflamed tissues. This implies that, in vivo, the interactions between DC undergoing maturation and CD56(bright) NK cells may occur in different tissues and have different functional implications.  相似文献   
54.
T-cell homeostasis is regulated by several molecules; among these, interleukin (IL)-7 plays an essential role in the survival and homeostatic proliferation of peripheral naive T cells. In a previous study, we investigated whether human mesenchymal stromal cells (MSCs) could be engineered with the IL-7 gene to produce functional level of this cytokine. In the present study, we analyzed the impact of different quantities of IL-7 produced by MSCs on the survival and proliferation of a negative immunoselected naive (CD3(+)/CD45RA(+)) T-cell population. Co-cultivation of peripheral naive T cells with MSCs producing low (16 pg/mL) or high (1000 pg/mL) IL-7 levels or in the presence of exogenous IL-7 (0.01 ng/mL and 100 ng/mL) maintained the CD3(+)/CD45RA(+) naive T-cell phenotype. Chemokine receptor CCR7(+) expression was also maintained among this T-cell population. Naive T-cell molecular characteristics were maintained as assessed by the Vbeta spectratyping complexity score, which showed the maintenance of a broad T-cell repertoire. No Th1 or Th2 differentiation was observed, as assessed by interferon-gamma or IL-4 accumulation. In contrast, only MSCs producing high amounts of IL-7 caused increased activation (CD25 31.2% +/- 12% vs 10% +/- 3.5%; P < .05), proliferation (CD71 17.8+/-7% vs 9.3%+/-3, P < .05), apoptosis (assessed by annexin V: 18.6% +/- 5% vs 14.9% +/- 2.6%; P > .05), and the phase S cell cycle (15% vs 6.9%, P > .05). Exogenous IL-7 exhibited no significant effect. In conclusion, we demonstrated that IL-7 produced by MSCs has a dose-independent effect on naive T-cell survival while exerting a dose-dependent effect on activation/proliferation. Due to the continuous production of IL-7 by engineered cells, our system is more efficacious than exogenous IL-7.  相似文献   
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Mycoplasma hyopneumoniae (Mh) is the primary agent of porcine enzootic pneumonia (PEN), a chronic respiratory disease endemic to pig farms, and characterized histologically by infiltration of mononuclear cells in airways and prominent hyperplasia of the bronchus-associated lymphoid tissue (BALT). To gain further insight into the pathogenesis of PEN, cytokine expression in the lung, with particular attention to the BALT, was examined immunohistochemically in pigs naturally infected with Mh. An increase (P < 0.05) in proinflammatory and immunoregulatory cytokines (especially interleukin [IL]-2, IL-4 and tumour necrosis factor [TNF]-alpha, and to a lesser extent IL-1 [alpha and beta] and IL-6) was detected in the BALT, which showed intense lymphoid hyperplasia. IL-1beta and TNF-alpha were also detected in the bronchoalveolar exudate of infected pigs, and IL-6 and IL-8 were demonstrated in mononuclear cells of the alveolar septa. The results showed that in Mh infection, macrophage and lymphocyte activation results in the expression of a number of cytokines capable of inducing lung lesions and lymphoreticular hyperplasia of the BALT.  相似文献   
58.
The majority of peripheral blood γδ T cells in human adults expresses T cell receptors (TCR) with identical V regions (Vγ9 and Vδ2). These Vγ9Vδ2 T cells recognize the major histocompatibility complex (MHC) class I-deficient B cell line Daudi and broadly distributed nonpeptidic antigens present in bacteria and parasites. Here we show that unlike αβ or Vγ9? γδ T cells, the majority of Vγ9Vδ2T cells harbor natural killer inhibitory receptors (KIR) (mainly CD94/NKG2A heterodimers), which are known to deliver inhibitory signals upon interaction with MHC class I molecules. Within Vγ9δ2 T cells, KIR were mainly expressed by clones exhibiting a strong lytic activity against Daudi cells. In stark contrast, almost all Vγ9Vδ2 T cell clones devoid of killing activity were KIR?, thus suggesting a coordinate acquisition of KIR and cytotoxic activity within Vγ9Vδ2 T cells. In functional terms, KIR inhibited lysis of MHC class I-positive tumor B cell lines by Vγ9Vδ2 cytotoxic T lymphocytes (CTL) and raised their threshold of activation by microbial antigens presented by MHC class I-positive cells. Furthermore, masking KIR or MHC class I molecules revealed a TCR-dependent recognition by Vγ9Vδ2 CTL of ligands expressed by activated T lymphocytes, including the effector cells themselves. Taken together, these results suggest a general implication of Vγ9Vδ2 T cells in immune response regulation and a central role of KIR in the control of self-reactive γδ CTL.  相似文献   
59.
Early dental caries detection will facilitate implementation of nonsurgical methods for arresting caries progression and promoting tooth remineralization. We present a method that combines optical coherence tomography (OCT) and Raman spectroscopy to provide morphological information and biochemical specificity for detecting and characterizing incipient carious lesions found in extracted human teeth. OCT imaging of tooth samples demonstrated increased light backscattering intensity at sites of carious lesions as compared to the sound enamel. The observed lesion depth on an OCT image was approximately 290 microm matching those previously documented for incipient caries. Using Raman microspectroscopy and fiber-optic-based Raman spectroscopy to characterize the caries further, spectral changes were observed in PO4 (3-) vibrations arising from hydroxyapatite of mineralized tooth tissue. Examination of various ratios of PO4 (3-) nu2, nu3, nu4 vibrations against the nu1 vibration showed consistent increases in carious lesions compared to sound enamel. The changes were attributed to demineralization-induced alterations of enamel crystallite morphology and/or orientation. OCT imaging is useful for screening carious sites and determining lesion depth, with Raman spectroscopy providing biochemical confirmation of caries. The combination has potential for development into a new fiber-optic diagnostic tool enabling dentists to identify early caries lesions with greater sensitivity and specificity.  相似文献   
60.
Rapid Flagella Stain   总被引:6,自引:3,他引:6       下载免费PDF全文
Leifson stain was modified to produce rapid staining of bacterial flagella on untreated microscope slides. The procedure was reliable when tested against a variety of motile and nonmotile bacteria.  相似文献   
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