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31.
The color complementation assay (CCA) is a method of allele-specific DNA amplification by which competitive priming and extension of fluorescently labeled oligonucleotide primers determine the color of DNA amplification product. This diagnostic method precludes the need for radioisotopes, electrophoresis, and multiple high-stringency reaction conditions. The multiplicity of mutant globin genes present in Southeast Asians complicates clinical diagnosis and underscores the importance of DNA-based diagnostic methods. We have applied CCA to distinguish beta A and beta E alleles. Competing 15mer primers were a fluorescein-labeled complement to beta A and a rhodamine-labeled complement to beta E, identical except for their central nucleotides. A common unlabeled primer was used to amplify DNA product, the color of which was determined by the perfectly complementary primer. Color photography and spectrofluorometry, as well as a method of black-white photography that we developed to distinguish fluorescein- and rhodamine- labeled DNA, were used to record results. We applied CCA to define the complex genotype of a Thai woman with thalassemia intermedia, 96% HbE, and 4% HbF whose possible genotypes included several permutations of alpha-thalassemia, beta-thalassemia, and beta E genes. zeta-Globin gene mapping of DNA doubly digested with Bg/II and Asp 718 showed the -alpha 3.7/--SEA genotype, and CCA confirmed homozygous beta E/beta E. The CCA is useful for diagnosing the compound hemoglobin genotypes of Southeast Asians and could be applied also to prenatal diagnosis in this population.  相似文献   
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Previous studies found that bone marrow (BM) allografts from DLA- identical littermates resulted in survival of two thirds of recipient dogs after otherwise lethal doses of 450 to 600 cGy of total body irradiation (TBI) because of successful allografts or autologous recovery after rejection of the allografts. The current study asked whether survival could be further improved by treating allograft recipients with recombinant canine granulocyte colony-stimulating factor (G-CSF), stem cell factor (SCF), or G-CSF/SCF. Of 21 dogs, 14 (67%) receiving allografts but no growth factors survived, 10 with successful allografts (including 5 mixed chimeras) and 4 with autologous recovery; whereas 7 animals died, 5 from infections during BM aplasia and 2 from acute graft-versus-host disease. By comparison, 30 of 34 dogs (88%) receiving hematopoietic growth factors in addition to the BM graft survived, 17 with successful allografts (including 10 mixed chimeras) and 13 with autologous recovery; whereas 4 died, all with infection related to BM aplasia after rejection of the allograft. Survival was similar for recipients of G-CSF, SCF, or the combination of G-CSF and SCF. Logistic regression analyses, which accounted for possible effects of TBI dose, showed a trend for improved survival in dogs receiving growth factors (P = .09), no change in allogeneic engraftment (P = .74), and a slight increase in autologous recovery (P = .22). In agreement with previous data, we found that grafts of BM from DLA-identical littermates improved survival of recipient dogs exposed to low but otherwise lethal doses of TBI. A further improvement in survival could be achieved by additional treatment with G-CSF, SCF, or G-CSF/SCF. Results suggest that treatment by hematopoietic growth factors along with BM grafts should be considered for victims of radiation accidents.  相似文献   
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Cone beam computed tomography is widely used in dentistry. Incidental findings are common, with many requiring intervention or monitoring. We present a rare case of previously undiagnosed, asymptomatic multiple myeloma first identified incidentally on cone beam computed tomography and panoramic radiography. This case highlights the diverse range of lesions that may appear on cone beam computed tomography and the importance of radiologic interpretation.  相似文献   
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Objectives: The Long Lasting Memories (LLM) program concerns a newly integrated platform which combines cognitive exercises with physical activity within the context of advanced technologies. The main objective of this study was to present the preliminary results that determine the possible effectiveness of the LLM program in the improvement of cognitive functions and symptoms of depression in healthy elderly and subjects with mild cognitive impairment (MCI). Method: Fifty healthy and MCI subjects participated in the study. All of them received one hour's physical training and 35 minutes’ cognitive training, 3 times a week, during the 12 weeks of the program. Before and after the intervention all participants were assessed using a battery of neuropsychological tests.Results: The results showed a significant improvement after the LLM training in global cognitive function, in verbal memory, in attention, in episodic memory and symptoms of depression. Conclusion: This study indicates that LLM is a promising solution for older adults with and without cognitive impairment, maintaining their wellbeing with few professional and technical requirements.  相似文献   
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Rationale: Viral myocarditis results from an adverse immune response to cardiotropic viruses, which causes irreversible myocyte destruction and heart failure in previously healthy people. The involvement of microRNAs and their usefulness as therapeutic targets in this process are unknown. Objective: To identify microRNAs involved in viral myocarditis pathogenesis and susceptibility. Methods and Results: Cardiac microRNAs were profiled in both human myocarditis and in Coxsackievirus B3-injected mice, comparing myocarditis-susceptible with nonsusceptible mouse strains longitudinally. MicroRNA responses diverged depending on the susceptibility to myocarditis after viral infection in mice. MicroRNA-155, -146b, and -21 were consistently and strongly upregulated during acute myocarditis in both humans and susceptible mice. We found that microRNA-155 expression during myocarditis was localized primarily in infiltrating macrophages and T lymphocytes. Inhibition of microRNA-155 by a systemically delivered LNA-anti-miR attenuated cardiac infiltration by monocyte-macrophages, decreased T lymphocyte activation, and reduced myocardial damage during acute myocarditis in mice. These changes were accompanied by the derepression of the direct microRNA-155 target PU.1 in cardiac inflammatory cells. Beyond the acute phase, microRNA-155 inhibition reduced mortality and improved cardiac function during 7 weeks of follow-up. Conclusions: Our data show that cardiac microRNA dysregulation is a characteristic of both human and mouse viral myocarditis. The inflammatory microRNA-155 is upregulated during acute myocarditis, contributes to the adverse inflammatory response to viral infection of the heart, and is a potential therapeutic target for viral myocarditis.  相似文献   
39.
We have recently demonstrated that peripheral blood monocytes from patients with multiple sclerosis (MS) have a defect in stimulating autologous and allogeneic T lymphocytes. This defect was found to correlate with disease activity. In this report we demonstrate that prothymosin alpha (ProT alpha), a rat thymus fraction 5 polypeptide, restores the MS monocyte stimulatory defect. The concentrations of ProT alpha which induced optimal enhancement of the mixed lymphocyte responses (MLR) were significantly higher when monocytes from patients with active disease were used as stimulators than when monocytes from patients with inactive disease were used. T4+ cells tested with autologous stimulatory monocytes harvested from an inactive stage of MS exhibited considerably higher proliferative responses than when stimulated with autologous monocytes obtained from an acute relapse. The decreased autologous proliferation of T4+ cells in MS patients was restored to normal levels after preincubation with ProT alpha in the environment of autologous monocytes. Our results demonstrate that ProT alpha is capable of fully restoring the deficient stimulatory function of MS monocytes and monocyte-associated functional defects of MS-derived T4+ cells.  相似文献   
40.
Congenital insensitivity to pain with anhidrosis (CIPA) or hereditary sensory and autonomic neuropathy type IV is a rare, autosomal recessive neurologic disorder, characterized by absence of reaction to painful stimuli, mental retardation, self- mutilating behavior, anhidrosis, and recurrent episodes of hyperthermia. Mutations in the neurotrophic tyrosine kinase receptor 1, a receptor phosphorylated by nerve growth factor, have been documented in diverse ethnic groups. We identified the same novel nonsense mutation in two unrelated families of Moroccan Jewish descent, each with two affected siblings. This possible founder mutation may trace to the rural Jewish village in southern Morocco from where both these families originated. Genetic screening for the causative mutation among 300 unrelated Moroccan Jews did not reveal carriers for the causative mutation, thus excluding high risk for CIPA in this ethnic subpopulation.  相似文献   
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