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91.
Background/AimMultiple sclerosis (MS) is an inflammatory, demyelinating disease of the central nervous system. Effector T helper cells, mainly Th1 and Th17, cytotoxic T-cells, B-cells, macrophages, microglia, and the cytokines they secrete, are implicated in the initiation and maintenance of a deregulated immune response to myelin antigens and the ensuing immune-mediated demyelination. In this study, we investigated whether signature cytokines exist in MS patients at presentation to gain an insight into the underlying immunopathogenic processes at the early stage of the disease.MethodsWe collected serum and cerebrospinal fluid (CSF) samples from 123 patients at presentation, eventually diagnosed with MS or non-inflammatory (NIND) or inflammatory neurological diseases (IND) or symptomatic controls (SC). The levels of cytokines IFN-γ, TNF-α, TGF-β1, IL-2, IL-4, IL-6, IL-10 and IL-17 were measured, and cytokine ratios, such as Th1/Th2, Th1/Th17, and Type-1/Type-2, were calculated. All parameters were tested for their correlations with the intrathecal IgG synthesis.ResultsCytokine levels in CSF were lower than in serum in all the patients, with the exception of IL-6. Serum or CSF cytokine levels of MS patients did not differ significantly from NIND or SC, with the exception of serum IFN-γ and TNF-α that were significantly higher in NIND. IND patients presented with the highest levels of all cytokines in serum and CSF, with the exception of serum IL-10 and CSF IL-17. MS patients had a significantly lower serum Th1/Th2 ratio compared to the NIND and IND groups, and significantly lower serum Type-1/Type-2, IFN-γ/IL-10 and CSF Th1/Th17 ratios compared to IND patients. MS patients had a significantly higher CSF IL-17/IL-10 ratio compared to IND patients. The IgG index was higher in MS patients compared to the control groups; the differences reached statistical significance between the MS and the NIND and SC groups. Reiber-Felgenhauer analysis of the QIgG and QAlb indices revealed higher intrathecal IgG synthesis in MS patients, and higher blood-CSF barrier dysfunction in IND patients. The IgG index correlated with CSF IL-4 in MS patients only.ConclusionsWe found no signature cytokines or profiles thereof in MS patients at presentation. Only IND patients presented with a clear Th1 cytokine polarization in serum and CSF. The parameters that distinguished MS patients from patients with other neurological disorders were IgG intrathecal synthesis, the IgG index and its correlation with CSF IL-4 levels.  相似文献   
92.
Vertebrate skin is characterized by its patterned array of appendages, whether feathers, hairs, or scales. In avian skin the distribution of feathers occurs on two distinct spatial levels. Grouping of feathers within discrete tracts, with bare skin lying between the tracts, is termed the macropattern, while the smaller scale periodic spacing between individual feathers is referred to as the micropattern. The degree of integration between the patterning mechanisms that operate on these two scales during development and the mechanisms underlying the remarkable evolvability of skin macropatterns are unknown. A striking example of macropattern variation is the convergent loss of neck feathering in multiple species, a trait associated with heat tolerance in both wild and domestic birds. In chicken, a mutation called Naked neck is characterized by a reduction of body feathering and completely bare neck. Here we perform genetic fine mapping of the causative region and identify a large insertion associated with the Naked neck trait. A strong candidate gene in the critical interval, BMP12/GDF7, displays markedly elevated expression in Naked neck embryonic skin due to a cis-regulatory effect of the causative mutation. BMP family members inhibit embryonic feather formation by acting in a reaction-diffusion mechanism, and we find that selective production of retinoic acid by neck skin potentiates BMP signaling, making neck skin more sensitive than body skin to suppression of feather development. This selective production of retinoic acid by neck skin constitutes a cryptic pattern as its effects on feathering are not revealed until gross BMP levels are altered. This developmental modularity of neck and body skin allows simple quantitative changes in BMP levels to produce a sparsely feathered or bare neck while maintaining robust feather patterning on the body.  相似文献   
93.
Multiplex PCR assays for the coamplification of microsatellite loci allow rapid and cost-effective genetic analyses and the production of efficient screening protocols for international breeding programs. We constructed a partial genomic library enriched for di-nucleotide repeats and characterized 14 new microsatellite loci for the Komodo monitor (or Komodo dragon, Varanus komodoensis). Using these novel microsatellites and four previously described loci, we developed multiplex PCR assays that may be loaded on a genetic analyser in three separate panels. We tested the novel set of microsatellites for polymorphism using 69 individuals from three island populations and evaluated the resolving power of the entire panel of 18 loci by conducting (i) a preliminary assignment test to determine population(s) of origin and (ii) a parentage analysis for 43 captive Komodo monitors. This panel of polymorphic loci proved useful for both purposes and thus can be exploited for fine-scale population genetic analyses and as part of international captive breeding programs directed at maintaining genetically viable ex situ populations and reintroductions.  相似文献   
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Ventilation rate and turnover rate of dry air vary among different types of ventilation systems used with individually ventilated cages (IVCs) and can affect the well-being of rodents housed in these cages. The authors compared the effects of two types of IVC systems, forced-air IVCs and motor-free IVCs, on 4-week-old C57Bl/6J male mice. The mice were acclimatized to the cages for 8 d and then monitored for 87 d. Their body weights, food and water consumption and preferred resting areas were recorded. Mice that were housed in motor-free IVCs had a significantly greater increase in body weight than those housed in forced-air IVCs, despite having similar food consumption. Mice in forced-air IVCs had greater water consumption than mice in motor-free IVCs. In addition, mice in forced-air IVCs were more frequently located in the front halves of their cages, whereas mice in motor-free IVCs were located with similar frequency in the front and back halves of their cages, perhaps because of the higher ventilation rate or the location of the air inlets and outlets in the rear of the cage. These results suggest that body weight, food and water consumption and intracage location of growing male mice are influenced by the type of ventilation system used in the cages in which the mice are housed.  相似文献   
97.
MbeA and MbeC are two key proteins in plasmid ColE1 conjugal mobilization. Isothermal titration calorimetry was used to detect and quantify an interaction between MbeA and MbeC. As a result of this interaction, the affinity of MbeA for single stranded DNA increased. The interaction was confirmed in vivo using a bacterial two-hybrid system, which revealed that MbeA-MbeC complexes are formed through the amino-terminal region of MbeA and the carboxy-terminal region of MbeC. To the best of our knowledge, this is the first report of direct interactions between conjugative proteins encoded by a mobilizable plasmid.  相似文献   
98.
Steps toward the identification of combi-molecules with strong abl tyrosine kinase (TK) inhibitory property and significant DNA damaging potential are described. The optimized combi-molecule 13a was shown to induce approximately twofold stronger abl TK inhibitory activity than Gleevec and high levels of DNA damage in chronic myelogenous leukemic cells.  相似文献   
99.
Salma A  Tsiapos A  Lazaridis I 《The FEBS journal》2007,274(19):5021-5027
Simian virus 40 large T antigen is a J-domain-containing protein with multiple functions. Among its numerous activities, T antigen can bind heat shock cognate 70 (hsc70) but the biological significance of this interaction has not been fully understood. Here, we show that T antigen can act as an hsc70 co-chaperone enhancing the protein-folding ability of the hsc70 chaperone machine. We also show that T antigen exerts its function in collaboration with the mammalian homologue of DnaJ. Moreover, we show that the participation of T antigen in the hsc70 chaperone machine has cell-type-specific characteristics.  相似文献   
100.
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