The moss, Physcomitrella patens has been used as a useful material in many fields, because of its simple body plan, ease of gene targeting, and other reasons. Although many mutants have been reported, no method to isolate the corresponding genes was reported. We developed a gene tagging and gene-trap system in P. patens by using the shuttle mutagenesis technique, which has been used in the budding yeast. In 5264 tagged lines, 203 mutants with altered developmental or morphological phenotypes were obtained. In 129 of 4757 gene-trap lines, beta-glucuronidase (GUS) activity was detected in some tissue. Although multiple copies of a tag were detected in many tagged lines by Southern analyses, most copies are likely integrated at the same locus according to PCR analyses.
Background: The stromal cell-derived factor-1/CXC chemokine receptor-4 (SDF-1/CXCR4) signal has been shown to be important in various immunological reactions. Recent studies have suggested that CXCR4 is expressed in certain cancer cells and that they use this chemokine receptor efficiently for metastasis formation. Method:The expression of CXCR4 was evaluated by immunohistochemical study in 79 surgically resected invasive ductal carcinomas, and the relation between the staining pattern and clinicopathological features was examined.Results: CXCR4 was diffusely and homogeneously expressed in 59 cancers, which were further divided into 28 highexpression and 31 low-expression cancers by their staining intensity. The other 20 cancers showed heterogeneous immunoreactivity in tumor tissue, which was defined as focal type. In comparison with the diffuse type, focal type tumors showed significantly more extensive lymph node metastasis, because the number and extent of metastatic nodes were larger in the focal than the diffuse type. In the diffuse type, the rate of node-positive cases did not show a difference in staining intensity. However, high-CXCR4 tumors showed more extensive nodal metastasis in comparison with low-expression tumors. In contrast, the expression pattern of CXCR4 did not have a significant correlation with hematogeneous metastasis. The overall survival of these patients tended to be better in the diffuse type than in the focal type, although the difference was not statistically significant. Conclusion:The expression pattern of CXCR4 was significantly correlated with the degree of lymph node metastasis in breast cancers. Our data suggest that CXCR4 might be particularly important in facilitating metastasis through the lymphatic system.
Combination chemotherapy of i.v. and i.p. PTX with S-1 is well tolerated and active in gastric cancer patients with peritoneal metastasis.
The plant-specific transcription factor LEAFY controls general aspects of the life cycle in a basal plant, the moss Physcomitrella patens. In contrast, LEAFY has more specialized functions in angiosperms, where it specifically induces floral fate during the reproductive phase. This raises the question of a concomitant change in the biochemical function of LEAFY during the evolution of land plants. We report that the DNA binding domain of LEAFY, although largely conserved, has diverged in activity. On the contrary, other, more rapidly evolving portions of the protein have few effects on LEAFY activity.
Pteridophytes have a longer evolutionary history than any other vascular land plant and, therefore, have endured greater loss of phylogenetically informative information. This factor has resulted in substantial disagreements in evaluating characters and, thus, controversy in establishing a stable classification. To compare competing casicatis, we obtained DNA sequences of a chloroplast gene. The sequence of 1206 nt of the large subunit of the ribulose-bisphosphate carboxylase gene (rbcL) was determined from 58 species, representing almost all families of leptosporangiate ferns. Phylogenetic trees were inferred by the neighbor-joining and the parsimony methods. The two methods produced almost identical phylogenetic trees that provided insights concerning major general evolutionary trends in the leptosporangiate ferns. Interesting findings were as follows: (i) two morphologically distinct heterosporous water ferns, Marula and Salvinia, are sister genera; (iu) the tree ferns (Cyatheaceae, Dicksoniaceae, and Metaxyaceae) are monophyletic; and (ui) polypodiolds are distantly related to the gleicheniolds in spite of the imilarit of their exindusiate soral morphology and are close to the higher indusiate ferns In addition, the affiities of several "problematic genera" were assessed.The extant ferns include -10,000 species and 250 genera in the world (1). They are the most conspicuous spore-bearing land plants and the principal members of land flora after the flowering plants. Ferns Based on morphology, the leptosporangiate ferns are usually classified into three major groups, Marsileaceae, Salviniaceae including Azollaceae, and the rest, which are often treated as different orders (5-7). Although both the Marsileaceae and the Salviniaceae have distinctive morphologies, both live in aquatic habitats and are characterized by heterospory, the latter being extremely rare in the leptosporangiate ferns. The phylogenetic relationship ofthese aquatic ferns to the homosporus ferns remains unsolved (8).Classification and phylogenetic relationships of the leptosporangiate ferns above the family level are controversial (1, 5,6,[8][9][10]. The reasons for discrepancy among classification schemes include disagreements in evaluation of morphological characters used. It is often difficult to identify homologous characters because similar characters are found in apparently different phylogenetic lineages; convergent or parallel evolution probably often occurred during the long evolutionary history of ferns (11). Furthermore, frequent extinctions produced missing links, which have resulted in difficulties elucidating phylogenetic interrelationships of major groups (1, 11). Micromolecular information (12) also is not useful to infer familial relationships for the same reasons.Recently molecular systematics in plants has progressed rapidly with in vitro DNA amplification (polymerase chain reaction, PCR) mediated by thermostable DNA polymerase and the direct sequencing methods. In angiosperm systematics, this molecular approach...
A hereditary ceruloplasmin deficiency associated with severe iron deposition in visceral organ and brain tissues found on histopathological examination at autopsy is discussed. Three siblings of consanguineous Japanese parents were studied. Their clinical symptoms were progressive dementia, extrapyramidal disorders, cerebellar ataxia, and diabetes mellitus, all of which appeared when they were between 30 and 50 years old. All had serum ceruloplasmin deficiencies and increased serum ferritin concentrations. The dentate nucleus, thalamus, putamen, caudate nucleus, and liver of each one showed low signal intensities on T1- and T2-weighted magnetic resonance images. Examination of the central nervous system revealed severe destruction of the basal ganglia and dentate nucleus, with considerable iron deposition in neuronal and glial cells, whereas the cerebral cortex showed mild iron deposition in glial cells without neuronal involvement. An electron microscopic study with energy-dispersive x-ray analysis showed iron depositions in the hepatocytes, of both the neural and glial cells of the brain. We consider this a new disease entity because of the primary ceruloplasmin deficiency.
The sundew genus Drosera consists of carnivorous plants with active flypaper traps and includes nearly 150 species distributed mainly in Australia, Africa, and South America, with some Northern Hemisphere species. In addition to confused intrageneric classification of Drosera, the intergeneric relationships among the Drosera and two other genera in the Droseraceae with snap traps, Dionaea and Aldrovanda, are problematic. We conducted phylogenetic analyses of DNA sequences of the chloroplast rbcL gene for 59 species of Drosera, covering all sections except one. These analyses revealed that five of 11 sections, including three monotypic sections, are polyphyletic. Combined rbcL and 18S rDNA sequence data were used to infer phylogenetic relationships among Drosera, Dionaea, and Aldrovanda. This analysis revealed that all Drosera species form a clade sister to a clade including Dionaea and Aldrovanda, suggesting that the snap traps of Aldrovanda and Dionaea are homologous despite their morphological differences. MacClade reconstructions indicated that multiple episodes of aneuploidy occurred in a clade that includes mainly Australian species, while the chromosome numbers in the other clades are not as variable. Drosera regia, which is native to South Africa, and most species native to Australia, were clustered basally, suggesting that Drosera originated in Africa or Australia. The rbcL tree indicates that Australian species expanded their distribution to South America and then to Africa. Expansion of distribution to the Northern Hemisphere from the Southern Hemispere occurred in a few different lineages.
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