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191.
Summary The morphopalynological cards ofThuja orientalis L. and ofCryptomeria japonica (L. fil.) D. Don were illustrated as part of a more comprehensive study on ornamental Pinophyta. Pollens from the original area of the two species were also compared with grains coming from plants cultivated in Italy. In the case ofCryptomeria japonica (L. fil.) D. Don DV, D01, D02, exine, min. and max. diameters, calculated on a japanese sample, differed significatively from the italian sample. In the case ofThuja orientalis L. no significant differences were observed. Pollen from the two italian sites did not show significative differences in size and shape. Pollens acetolysed with the traditional method (Erdtman, 1960) were compared with pollens treated with the Tatzreiter method (1985). Morphometric analysis showed similar values for both species.  相似文献   
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The human salivary acidic proline-rich proteins (aPRPs) complex was investigated by different chromatographic and mass spectrometric approaches and the main aPRPs, namely PRP-1, PRP-2 and PIF-s (15,515 amu), Db-s (17,632 amu) and Pa (15,462 amu) proteins, were detected. All these isoforms are phosphorylated at Ser-8 and Ser-22 and have a pyroglutamic moiety at the N-terminus. Apart from Pa, all the other aPRPs undergo a proteolytic cleavage at Arg-106 residue (Arg-127 in Db-s protein), that generates the small PC peptide (4371 amu) and PRP-3, PRP-4, PIF-f (11,162 amu) and Db-f (13,280 amu) proteins, all of which were detected. With regard to the Pa protein, the main form detected was the dimeric derivative (Pa 2-mer, 30,922 amu) originated by a disulfide bond involving Cys-103 residue. Besides these known isoforms, several previously undetected aPRP derivatives were found (in minor amounts): (i) the triphosphorylated derivatives of PRP-1/PRP-2/PIF-s and Db-s, showing the additional phosphate group at Ser-17; (ii) the mono-phosphorylated forms at either Ser-22 or Ser-8 of PRP-1/PRP-2/PIF-s, PRP-3/PRP-4/PIF-f, Db-s and Db-f; (iii) a nonphosphorylated form of PRP-3/PRP-4/PIF-f; (iv) the triphosphorylated and diphosphorylated forms of Pa 2-mer. Moreover, minor quantities of PRP-3/PRP-4/PIF-f lacking the C-terminal Arg (11,006 amu), and of Pa 2-mer lacking the C-terminal Gln (30,793 amu) were found. By this approach the different phenotypes of PRH1 locus in 59 different subjects were characterized.  相似文献   
195.
Innexins are a family of transmembrane proteins involved in the formation of gap junctions, specific intercellular channels, in invertebrates. Analyses of the entire innexin family during Drosophila melanogaster embryonic development shows the occurrence of complex and specific patterns of expression of the different genes. Innexins inx-2 and inx-7, in general, do not appear to exhibit extensive co-expression in different D. melanogaster cellular compartments. We propose here a new and robust mechanism, based on our analysis of the genomic organization of inx-2 and inx-7, that structurally justifies the reciprocal expression of genes.  相似文献   
196.
As a part of an ongoing search for new isoniazid-related isonicotinoylhydrazones (ISNEs), 2'-monosubstituted isonicotinohydrazides and cyanoboranes, some analogues belonging to these three series of compounds were further evaluated in an in vitro advanced antimycobacterial screening. The results here reported allowed us to extend their structure-activity relationships. A general correlation emerged between their lipophilicity and effectiveness against intracellular M. tuberculosis. On the whole, the most interesting result of this research was that some hydrazides and ISNEs proved to be more effective antimycobacterial agents than parental isoniazid in a TB-infected macrophage model.  相似文献   
197.
Starting from various cyclic or bicyclic ketones, we have synthesized novel Pifithrin-alpha analogues bearing different methyl substituted phenyl ketone groups at the N3-position of the 2-iminothiazole heterocycle. From stability studies in a biological medium as well as under specific chemical conditions, we have shown by NMR techniques that through a dehydration process, some derivatives can generate their corresponding cyclized analogues. All of the new analogues, Pifithrin-like and polycyclic dehydrated derivatives were assessed for their p53 inactivation potency by measuring survival of cortical neurons, whose death was induced by the DNA-damaging agent etoposide. Pifithrin-alpha like 2f as well as the cyclic dehydrated 6b analogue were found to be one log more potent p53 inactivators than reference compound Pft-alpha, with EC50 values ranging around 30 nM. These results support the finding that p53 inactivation by Pft-alpha analogues could be also due to the presence of the cyclic dehydrated Pft-alpha forms, generated in situ in the biological assay incubation medium.  相似文献   
198.
Thirteen samples of human normal whole saliva were analyzed by RP-HPLC-ESI-MS and MALDI-TOF-MS to investigate the basic proline-rich protein complex. Between known basic-PRPs the P-B, P-C (or IB-8b), P-D (or IB-5), P-E (or IB-9), P-F (or IB-8c), P-H (or IB-4), IB-6, II-2, IB-1, and IB-8a glucosylated were identified, whereas the II-1, IB-7, PA, and D1-A peptides were not detected. Some detected masses not attributable to known basic-PRPs were putatively ascribed to II-2 and IB-1 nonphosphorylated, II-2 and IB-1 missing the C-terminal arginine residue, and the 1-62 fragment of IB-6, named P-J peptide. A correlation matrix analysis revealed a cluster of correlation among all the basic PRPs (apart from the P-B peptide) which is in agreement with their common parotid origin.  相似文献   
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