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Molecular Biology Reports - TBI is the main cause of death and disability in individuals aged 1–45 in Western countries. One of the main challenges of TBI at present is the lack of specific...  相似文献   
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The human leukocyte antigen (HLA) complex on chromosome 6p21 has been unambiguously associated with multiple sclerosis (MS). The complex features of the HLA region, especially its high genic content, extreme polymorphism, and extensive linkage disequilibrium, has prevented to resolve the nature of HLA association in MS. We performed a family based association study on the isolated population of the Nuoro province (Sardinia) to clarify the role of HLA genes in MS. The main stage of our study involved an analysis of the ancestral haplotypes A2Cw7B58DR2DQ1 and A30Cw5B18DR3DQ2. On the basis of a multiplicative model, the effect of the first haplotype is protective with an odds ratio (OR) = 0.27 (95% confidence interval CI 0.13–0.57), while that of the second is deleterious, OR 1.78 (95% CI 1.26–2.50). We found both class I (A, Cw, B) and class II (DR, DQ) loci to have an effect on MS susceptibility, but we saw that they act independently from each other. We also performed an exploratory analysis on a set of 796 SNPs in the same HLA region. Our study supports the claim that Class I and Class II loci act independently on MS susceptibility and this has a biological explanation. Also, the analysis of SNPs suggests that there are other HLA genes involved in MS, but replication is needed. This opens up new perspective on the study of MS.  相似文献   
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The human D5 monoclonal antibody binds to the highly conserved hydrophobic pocket on the N-terminal heptad repeat (NHR) trimer of HIV-1 gp41 and exhibits modest yet relatively broad neutralization activity. Both binding and neutralization depend on residues in the complementarity determining regions (CDRs) of the D5 IgG variable domains on heavy chain (VH) and light chain (VL). In an effort to increase neutralization activity to a wider range of HIV-1 strains, we have affinity matured the parental D5 scFv by randomizing selected residues in 5 of its 6 CDRs. The resulting scFv variants derived from four different CDR changes showed enhanced binding affinities to gp41 NHR mimetic (5-helix) which correlated to improved neutralization potencies by up to 8-fold. However, when converted to IgG1s, these D5 variants had up to a 12-fold reduction in neutralization potency over their corresponding scFvs despite their slightly enhanced in vitro binding affinities. Remarkably, D5 variant IgG1s bearing residue changes in CDRs that interact with epitope residues N-terminal to the hydrophobic pocket (such as VH CDR3 and VL CDR3) retained more neutralization potency than those containing residue changes in pocket-interacting CDRs (such as VH CDR2). These results provide compelling evidence for the existence of a steric block to an IgG that extends to the gp41 NHR hydrophobic pocket region, and can be a useful guide for developing therapeutic antibodies and vaccines circumventing this block.  相似文献   
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Macular disease is one of the main causes of visual impairment. We studied the efficacy of low-vision rehabilitation by means of MP-1 biofeedback examination in patients with different macular disease. Five patients were enrolled (3 female and 2 male, mean age 53.8 years) and a total of 9 eyes was examined: 2 eyes with vitelliform dystrophy, 1 with a post-traumatic macular scar, 2 with Stargardt disease, 2 with myopic macular degeneration, 2 with cone dystrophy. All the patients underwent the following tests: visual acuity, reading speed, fixation test, MP-1 microperimetry. Low-vision rehabilitation, which lasted 10 weeks, consisted of 10 training sessions of 10 min for each eye, performed once a week using the MP-1 biofeedback examination. Statistical analysis was performed using Student’s t-test. p values less than 0.05 were considered statistically significant. After training all patients displayed an improvement in visual acuity, fixation behaviour, retinal sensitivity and reading speed. Fixation behaviour within the 2° diameter circle improved and was statistically significant for reading speed (p = 0.01). Reading speed improved from a mean value of 64.3 to 92 words/min. Our results show that audio feedback can, by increasing attentional modulation, help the brain to fix the final preferred retinal locus. Audio feedback facilitates stimuli transmission between intraretinal neurons as well as between the retina and brain, which is where the highest level of stimuli processing occurs, thereby probably supporting a “remapping phenomenon”.  相似文献   
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Vegetation History and Archaeobotany - Knowledge about the vegetation history of Sardinia, the second largest island of the Mediterranean, is scanty. Here, we present a new sedimentary record...  相似文献   
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The International Journal of Life Cycle Assessment - A challenge that the road paving sector is facing concerns the achievement of highly performing bituminous asphalt mixture solutions that do not...  相似文献   
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