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91.
To better understand the biogenesis of viroid-specific small RNAs and their possible role in disease induction, we have examined the accumulation of these small RNAs in potato spindle tuber viroid (PSTVd)-infected tomato plants. Large-scale sequence analysis of viroid-specific small RNAs revealed active production from the upper portion of the pathogenicity and central domains, two regions previously thought to be underrepresented. Profiles of small RNA populations derived from PSTVd antigenomic RNA were more variable, with differences between infected Rutgers (severe symptoms) and Moneymaker (mild symptoms) plants pointing to possible cultivar-specific differences in small RNA synthesis and/or stability. Using microarray analysis, we monitored the effects of PSTVd infection on the expression levels of > 100 tomato genes containing potential binding sites for PSTVd small RNAs. Of 18 such genes down-regulated early in infection, two genes involved in gibberellin or jasmonic acid biosynthesis contain binding sites for PSTVd small RNAs in their respective ORFs.  相似文献   
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Nod2 belongs to the nucleotide-binding domain leucine-rich repeat family of proteins and senses bacterial cell wall components to initiate innate immune responses against various pathogens. Recently, it has been reported that T-cell-intrinsic expression of Nod2 promotes host defense against Toxoplasma gondii infection by inducing type 1 immunity. Here, we present results that demonstrate that Nod2 does not play a role in the defense against T. gondii infection. Nod2-deficient mice were fully capable of inducing Th1 immune responses and did not show enhanced susceptibility to infection. Upon TCR stimulation in vitro, Nod2-deficient CD4(+) T cells showed normal activation, IL-2 production, proliferation, and Th1/2 differentiation. Nod2 mRNA and protein were expressed in CD4(+) T and CD8(+) T cells at substantial levels. Therefore, Nod2, although expressed in CD4(+) T cells, does not have an intrinsic function in T-cell activation and differentiation.  相似文献   
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Background  

The efficacy and safety of the association of celecoxib [a selective cyclooxygenase-2 (COX-2) inhibitor] and pregabalin (commonly used to control neuropathic pain), compared with monotherapy of each, were evaluated for the treatment of chronic low-back pain, a condition known to be due to neuropathic as well as nociceptive pain mechanisms.  相似文献   
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OBJECTIVE: Systemic mastocytosis with associated clonal hematological non-mast cell lineage disease (SM-AHNMD) is a distinct entity that was defined by World Health Organization. Systemic mastocytosis with acute myeloid leukemia (AML) is frequently seen among SM-AHNMD. However, the pathogenesis or origin of neoplastic mast cells has not been fully elucidated in this category of diseases. METHODS: We examined KIT mutation, chimeric status, and AML1/ETO mRNA concerning mast cells and immature hematopoietic cells of the bone marrow in a patient with systemic mastocytosis with AML1/ETO-positive AML following allogeneic hematopoietic stem cell transplantation (HSCT). RESULTS: Mast cells of the patient displayed KIT D816Y mutation, and were derived from the recipient. In contrast, immature hematopoietic cells as defined by CD34+ CD117+ were derived from the donor, which did not possess detectable KIT D816Y mutation. The ratio of AML1/ETO to 18S rRNA of the mast cells was 7.53, whereas that of immature hematopoietic cells was 1.67. CONCLUSIONS: In a patient with SM-AHNMD who underwent allogeneic HSCT, the major source of the detectable AML1/ETO mRNA of the bone marrow after transplantation was neoplastic mast cells with KIT mutation, which were thought to be derived from CD34+ CD117+ immature leukemic cells of the recipient.  相似文献   
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We present a 59-year-old woman who underwent combined pulmonary resection for bronchiectasis with massive, recurrent hemoptysis and redo coronary artery bypass. She had previously been hospitalized four times for massive hemoptysis. She had also undergone coronary artery bypass and had symptomatic severe graft disease. We performed simultaneous right middle lobectomy and redo triple bypass. At surgery, lobectomy was performed before heparinization, then redo bypass was performed using on-pump cardiopulmonary bypass. The postoperative course was uneventful.  相似文献   
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Although immunosuppressive therapy using antithymocyte globulin or cyclosporine A (CSA) is effective in selected patients with low-risk myelodysplastic syndrome, the response rates reported so far are inconsistent, and the indication of immunosuppressive therapy for myelodysplastic syndrome has not been clearly defined. We treated 20 myelodysplastic syndrome patients (17 refractory anemia cases [RA], 2 RA with excess blasts, and one RA with ringed sideroblasts) with 4 mg/kg per day of CSA for 24 weeks. Among the 19 patients evaluated, 10 showed hematologic improvement; 8 patients showed an erythroid response, 6 showed a platelet response, and one showed a neutrophil response. Most patients with hematologic improvement continued CSA thereafter, and the progressive response was observed until the latest follow-up (median, 30 months). Most toxicities associated with CSA usage were manageable, and no patient had developed acute leukemia up to this point. Short duration of illness, refractory anemia with minimal dysplasia determined by bone marrow morphology, and the presence of paroxysmal nocturnal hemoglobinuria-type cells were significantly associated with the platelet response. A minority of RA patients who did not possess such predictive variables achieved an isolated erythroid response. In conclusion, CSA may be a therapeutic option for patients with RA who do not have adverse prognostic factors.  相似文献   
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