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151.
Records of derogenid digeneans in the Mediterranean and Black Sea region are scarce and tend to be restricted to a small number of host-groups, but especially to sparid fishes. This work reports on the presence of derogenine and halipegine derogenids from two sparids, Diplodus annularis (L.) and D. sargus (L.), from off the Mediterranean coast of Spain. Five derogenid forms were recovered. Derogenes adriaticus Nikolaeva, 1966 is redescribed from Diplodus annularis, and Derogenes sp. is described from the same host but differentiated from the former species. Magnibursatus barretti n. sp. is described from Diplodus sargus and distinguished from other species of the genus especially by its smaller body size and smaller eggs. M. bartolii Kostadinova, Power, Fernández, Balbuena, Raga & Gibson, 2003 is redescribed from D. sargus, a new host for this species. A single specimen from D. sargus, somewhat similar to M. minutus Kostadinova, Power, Fernández, Balbuena, Raga & Gibson, 2003, is also described, as it exhibits some morphometric differences from the latter species.  相似文献   
152.
The most thoroughly characterized mammalian IAP is XIAP/BIRC4, which can inhibit caspases 9, 3 and 7, but may also regulate apoptosis through interactions with other proteins such as Smac/DIABLO, HtrA2/Omi, XAF1, TAK1, cIAP1, and cIAP2.High throughput sequencing of the mouse genome revealed the existence of a gene resembling Xiap/Birc4 on mouse chromosome 7. To confirm the existence of this gene, and to determine its functional significance, we performed Southern and Northern blot analysis. This showed the presence of the Xiap-like gene in both wild-type and Xiap gene knock-out mice, but the corresponding mRNA was not detected in any tissues examined by Northern blot. Analysis of the gene sequence in all three possible reading frames predicts that expression of this gene would not give rise to a full-length protein, but only non-functional truncated polypeptides. Because its nucleotide sequence is 92% identical to Xiap, but it has no introns corresponding to those of Xiap, we conclude that Xiap-ps1 is a pseudogene generated by retro-transposition of a spliced Xiap message to chromosome 7.  相似文献   
153.
Dehydroamino acids are non‐coded amino acids that offer unique conformational properties. Dehydrophenylalanine (ΔPhe) is most commonly used to modify bioactive peptides to constrain the topography of the phenyl ring in the side chain, which commonly serves as a pharmacophore. The Ramachandran maps (in the gas phase and in CHCl3 mimicking environments) of ΔPhe analogues with methyl groups at the β position of the side chain as well as at the C‐terminal amide were calculated using the B3LYP/6‐31 + G** method. Unexpectedly, β‐methylation alone results in an increase of conformational freedom of the affected ΔPhe residue. However, further modification by introducing an additional methyl group at C‐terminal methyl amide results in a steric crowding that fixes the torsion angle ψ of all conformers to the value 123°, regardless of the Z or E position of the phenyl ring. The number of conformers is reduced and the accessible conformational space of the residues is very limited. In particular, (Z)‐Δ(βMe)Phe with the tertiary C‐terminal amide can be classified as the amino acid derivative that has a single conformational state as it seems to adopt only the β conformation. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
154.
The taxonomic framework of the Haploporidae is evaluated and the relationships within the Haploporinae are assessed for the first time at the generic level using molecular data. Partial 28S and complete ITS2 rDNA sequences from representatives of six of the nine recognised genera within the Haploporinae were analysed together with published sequences representing members of two haploporid subfamilies and of the closely related family Atractotrematidae. Molecular analyses revealed: (i) a close relationship between the Atractotrematidae and the Haploporidae; (ii) strong support for the monophyly of the Haploporinae, Dicrogaster and Saccocoelium, and the position of Ragaia within the Haploporinae; (iii) evidence for rejection of the synonymy of Saccocoelioides and Lecithobotrys and the validity of the Dicrogasterinae; and (iv) support for the distinct status of Saccocoelium in relation to Haploporus. The wider sampling within the genera Dicrogaster and Saccocoelium confirmed the distinct status of the included species, thus rejecting previously suggested synonymies. Saccocoelioides, recently transferred to the Chalcinotrematinae, was nested within the Haploporinae and this was largely associated with the position of Forticulcita, resolved as the most basal haploporine genus. Forticulcita also possesses a well-delimited eversible intromittent copulatory organ, a feature unique in the Haploporidae which has not been previously considered an important apomorphy. This, in association with the present hypothesis of the Haploporinae based on molecular data, led us to erect Forticulcitinae subf. n. for Forticulcita; this resolved Saccocoelioides and, by extension the Chalcinotrematinae, as sister groups to the Haploporinae.  相似文献   
155.
Alternate treatments of Allium cepa root meristems with hydroxyurea (HU) and caffeine give rise to extremely large and highly elongated cells with atypical images of mitotic divisions, including internuclear asynchrony and an unknown type of interchromosomal asynchrony observed during metaphase-to-anaphase transition. Another type of asynchrony that cannot depend solely on the increased length of cells was observed following long-term incubation of roots with HU. This kind of treatment revealed both cell nuclei entering premature mitosis and, for the first time, an uncommon form of mitotic abnormality manifested in a gradual condensation of chromatin (spanning from interphase to prometaphase). Immunocytochemical study of polykaryotic cells using anti-β tubulin antibodies revealed severe perturbations in the microtubular organization of preprophase bands. Quantitative immunofluorescence measurements of the control cells indicate that the level of cyclin B-like proteins reaches the maximum at the G2 to metaphase transition and then becomes reduced during later stages of mitosis. After long-term incubation with low doses of HU, the amount of cyclin B-like proteins considerably increases, and a significant number of elongated cells show gradients of these proteins spread along successive regions of the perinuclear cytoplasm. It is suggested that there may be a direct link between the effects of HU-mediated deceleration of S- and G2-phases and an enhanced concentration of cyclin B-like proteins. In consequence, the activation of cyclin B-CDK complexes gives rise to an abnormal pattern of premature mitotic chromosome condensation with biphasic nuclear structures having one part of chromatin decondensed, and the other part condensed.  相似文献   
156.
157.
Cell and developmental studies have clarified how, by the time of implantation, the mouse embryo forms three primary cell lineages: epiblast (EPI), primitive endoderm (PE), and trophectoderm (TE). However, it still remains unknown when cells allocated to these three lineages become determined in their developmental fate. To address this question, we studied the developmental potential of single blastomeres derived from 16- and 32-cell stage embryos and supported by carrier, tetraploid blastomeres. We were able to generate singletons, identical twins, triplets, and quadruplets from individual inner and outer cells of 16-cell embryos and, sporadically, foetuses from single cells of 32-cell embryos. The use of embryos constitutively expressing GFP as the donors of single diploid blastomeres enabled us to identify their cell progeny in the constructed 2n↔4n blastocysts. We showed that the descendants of donor blastomeres were able to locate themselves in all three first cell lineages, i.e., epiblast, primitive endoderm, and trophectoderm. In addition, the application of Cdx2 and Gata4 markers for trophectoderm and primitive endoderm, respectively, showed that the expression of these two genes in the descendants of donor blastomeres was either down- or up-regulated, depending on the cell lineage they happened to occupy. Thus, our results demonstrate that up to the early blastocysts stage, the destiny of at least some blastomeres, although they have begun to express markers of different lineage, is still labile.  相似文献   
158.
159.
Leiomodin (Lmod) is a muscle-specific F-actin–nucleating protein that is related to the F-actin pointed-end–capping protein tropomodulin (Tmod). However, Lmod contains a unique ∼150-residue C-terminal extension that is required for its strong nucleating activity. Overexpression or depletion of Lmod compromises sarcomere organization, but the mechanism by which Lmod contributes to myofibril assembly is not well understood. We show that Tmod and Lmod localize through fundamentally different mechanisms to the pointed ends of two distinct subsets of actin filaments in myofibrils. Tmod localizes to two narrow bands immediately adjacent to M-lines, whereas Lmod displays dynamic localization to two broader bands, which are generally more separated from M-lines. Lmod''s localization and F-actin nucleation activity are enhanced by interaction with tropomyosin. Unlike Tmod, the myofibril localization of Lmod depends on sustained muscle contraction and actin polymerization. We further show that Lmod expression correlates with the maturation of myofibrils in cultured cardiomyocytes and that it associates with sarcomeres only in differentiated myofibrils. Collectively, the data suggest that Lmod contributes to the final organization and maintenance of sarcomere architecture by promoting tropomyosin-dependent actin filament nucleation.  相似文献   
160.

Background

Autistic spectrum disorders are a group of neurological and developmental disorders associated with social, communication, sensory, behavioral and cognitive impairments, as well as restricted, repetitive patterns of behavior, activities, or interests.The aim of this study was a) to analyze QEEG findings of autistic patients and to compare the results with data base; and b) to introduce the calculation of spectrum weighted frequency (brain rate) as an indicator of general mental arousal in these patients.

Results

Results for Q-EEG shows generally increased delta-theta activity in frontal region of the brain. Changes in QEEG pattern appeared to be in a non-linear correlation with maturational processes.Brain rate measured in CZ shows slow brain activity (5. 86) which is significantly lower than normal and corresponds to low general mental arousal.Recent research has shown that autistic disorders have as their basis disturbances of neural connectivity. Neurofeedback seems capable of remediating such disturbances when these data are considered as part of treatment planning.

Conclusions

Prognosis of this pervasive disorder depends on the intellectual abilities: the better intellectual functioning, the possibilities for life adaptation are higherQEEG shows generally increased delta-theta activity in frontal region of the brain which is related to poor cognitive abilities.Brain rate measured in CZ shows slow brain activity related to under arousal.Pharmacotherapy combined with behavior therapy, social support and especially neurofeedback technique promise slight improvements
  相似文献   
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