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61.
62.
Aberrant production of IL-21 by T cells is critical for the development of type 1 diabetes (T1D) in NOD mice. The pathogenic effects of IL-21 are partly due to its ability to promote the generation of T(H)-17 cells. Interferon Regulatory Factor (IRF4) is a crucial regulator of IL-17 and IL-21 production. We recently found that the serine-threonine kinase ROCK2 phosphorylates IRF4 and regulates its ability to control IL-17 and IL-21 production. Here we show that NOD T cells aberrantly activate ROCK2. We furthermore demonstrate that ROCK inhibition corrects the abnormal IRF4 function in NOD T cells and diminishes their production of IL-17 and IL-21. Importantly, administration of a ROCK inhibitor to NOD mice protects against diabetes development. These studies thus support the idea that ROCK2 is inappropriately activated in NOD T cells and that ROCK kinases could represent important therapeutic targets for the treatment of T1D.  相似文献   
63.
Introduced pumpkinseed in Iberian reservoirs display marked external morphological differentiation along two simultaneous dimensions of flow and trophic structure. We assessed the degree of internal morphological differentiation using gill rakers, pharyngeal jaws and the levator posterior muscle among pumpkinseeds occupying four different habitats and determined whether prey consumption accounted for any discernible differences in feeding structures among ecomorphs. Results showed significant differentiation by habitat based on pharyngeal muscle and jaw dimensions in all study reservoirs, with pelagic pumpkinseeds having smaller jaws than littoral pumpkinseeds in four of the five reservoirs. Gill rakers, however, differentiated morphs in only three of the five reservoirs, corresponding to differences in zooplankton consumption among pelagic and littoral individuals in those reservoirs. Based on all internal morphological traits, greater divergence was seen along the littoral-pelagic trophic axis in the lacustrine zones of reservoirs compared to the fluvial zone. Overall differences noted in internal morphology are likely the result of phenotypic plasticity; the ability of this species to readily adapt to changing physical environments may explain the success of the pumpkinseed in its introduced range.  相似文献   
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Synthetic oligodeoxyribonucleotides containing CpG dinucleotides exhibit potent immunostimulatory activity in vertebrates. Although the molecular mechanisms of recognition and interaction of CpG DNA sequences with receptors are not well understood, the current evidence suggests that the receptor shows considerable selectivity for CpG DNA sequences with different preferences in mouse (GACGTT) and human (GTCGTT) species. In our continued effort to understand the chemical and structural characteristics of CpG DNA required for the immunostimulatory activity and thereby for the recognition of receptors in the immunostimulatory pathway, we examined the requirement of nucleobases in the two adjacent nucleotide positions on the 5'- and the 3'-side to the CpG dinucleotide (P(1)P(2)CGP(3)P(4)) for the immunostimulatory activity. These studies, in which a natural nucleoside is substituted with an abasic nucleoside (X), suggest that a nucleobase is absolutely required in C, G, P(3), and P(4) positions for immunostimulatory activity. Surprisingly, an abasic nucleoside is permitted at either P(1) or P(2) depending on the neighboring base. It was found that 'GXCGTT' motif has an intermediate immunostimulatory activity between those of 'GACGTT' and 'GTCGTT' in the mouse cells.  相似文献   
66.
Trichoderma, soil-borne filamentous fungi, are capable of parasitising several plant pathogenic fungi. Twelve isolates of Trichoderma spp. isolated from different locations of South Andaman were characterized for their cultural, morphological and antagonistic activity against soil borne and foliar borne pathogens. The sequencing of these isolates showed seven different species. The isolates revealed differential reaction patterns against the test pathogens viz., Sclerotium rolfsii, Colletotrichum gloeosporioides and C. capsici. However, the isolates, TND1, TWN1, TWC1, TGD1 and TSD1 were most effective in percentage inhibition of mycelial growth of test pathogens. Significant chitinase and β-1,3-glucanase activities of all Trichoderma isolates has been recorded in growth medium. T. viride was found with highest chitinase whereas T. harzianum was recorded with highest β-1,3-glucanase activities.  相似文献   
67.
In continuation of our studies with stabilized immune modulatory RNA (SIMRA) compounds, we have synthesized novel SIMRA compounds incorporating arabinonucleotides to study their effects on TLR7 and TLR8 activation. The SIMRA compounds containing ara-G, ara-C, ara-U or ara-A substitutions activated TLR8 in HEK293 cells. Interestingly, the SIMRA compound containing ara-C also activated TLR7 and stimulated immune responses in vivo in mice. In human PBMC and pDC assays, SIMRA compounds containing arabinonucleotides induced Th1-type cytokine profiles. These results suggest that SIMRA compounds containing arabinonucleotides act as agonists of TLR7 and TLR8.  相似文献   
68.

An efficient in vitro propagation system has been developed for the rapid micropropagation of Thymus serpyllum L. (Banajwain), an aromatic medicinal herb from nodal explant on MS medium. Phenolic leaching and high rate of contamination was the most significant problem in establishing in vitro culture of Thymus serpyllum which was overcome by preparing explants in an antioxidant ascorbic acid (1000 ppm) at 6°C for 45 min and addition of the same antioxidant (50 mgl−1) to the MS medium. The frequency of shoot production was influenced by different cytokinins (Kn, BAP, and Kn + BAP) and 95.56% shoot induction was observed when MS medium was supplemented with 1.0 + 2.0 mgl−1 (Kn + BAP). The maximum average number of shoots 16.93 ± 2.15 and average length (3.98 ± 0.55) was recorded when MS medium have 0.5 + 2.0 mgl−1 (Kn + BAP). The in vitro regenerated microshoots were rooted on MS and half strength MS medium and there was significant difference in root induction on both media under the influence of auxins (IAA, IBA, and NAA). The maximum average number (11.67 ± 3.03) and average root length (3.88 ± 0.71) was reported in half MS medium having 1.0 mgl−1 IBA. The complete regenerated plantlets were acclimatized under growth chamber before transferring to the earthen pots and showed 90% survival.

Graphical abstract

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69.
Comment on 'Capnography as an aid in localizing the phrenic nerve in brachial plexus surgery. Technical note' Bhagat H, Agarwal A, Sharma MS Journal of Brachial Plexus and Peripheral Nerve Injury 2008, 3:14 (22 May 2008)  相似文献   
70.
Oligodeoxyribonucleotides containing CpG dinucleotides (CpG DNAs) are currently being evaluated as novel immunomodulators in clinical trials. Recently, we showed that an accessible 5′ end is required for immunostimulatory activity and blocking the 5′ end of CpG DNA by conjugation of certain ligands abrogates immunostimulatory activity. Based on these results, we designed and synthesized 3′–3′-linked CpG DNAs that contained two or more identical CpG DNA segments, referred to here as ‘immunomers’. The use of solid support bearing diDMT-glyceryl-linker permitted convenient synthesis of immunomers with both segments synthesized simultaneously, giving better yields and purity. The in vitro and in vivo studies suggest that as a result of accessibility to two 5′ ends for recognition, immunomers show an enhanced immunostimulatory activity compared with linear CpG DNAs. We also studied the suitability of a number of different linkers for attaching the two segments of immunomers. A C3-linker was found to be optimal for joining the two segments of immunomers. Incorporation of multiple linkers between the two segments of immunomers resulted in different cytokine profiles depending on the nature and number of linkers incorporated. Additionally, the length of immunomer also plays a significant role in inducing immune responses. An immunomer containing 11 nt in each segment showed the highest activity and an 11mer linear CpG DNA failed to stimulate an immune response. These results suggest that immunomers have several advantages over conventional linear CpG DNAs for immunomodulatory activity studies.  相似文献   
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