The complete plastid genome sequence of the enigmatic moss, Takakia lepidozioides (Takakiopsida, Bryophyta): evolutionary perspectives on the largest collection of genes in mosses and the intensive RNA editing.

KEY MESSAGE: Complete chloroplast genome sequence of a moss, Takakia lepidozioides (Takakiopsida) is reported. The largest collection of genes in mosses and the intensive RNA editing were discussed from evolutionary perspectives. We assembled the entire plastid genome sequence of Takakia lepidozioides (Takakiopsida), emerging from the first phylogenetic split among extant mosses. The genome sequences were assembled into a circular molecule 149,016 bp in length, with a quadripartite structure comprising a large and a small single-copy region separated by inverted repeats. It contained 88 genes coding for proteins, 32 for tRNA, four for rRNA, two open reading frames, and at least one pseudogene (tufA). This is the largest number of genes of all sequenced plastid genomes in mosses and Takakia is the only moss that retains the seven coding genes ccsA, cysA, cysT, petN rpoA, rps16 and trnPGGG. Parsimonious interpretation of gene loss suggests that the last common ancestor of bryophytes had all seven genes and that mosses lost at least three of them during their diversification. Analyses of the plastid transcriptome identified the extraordinary frequency of RNA editing with more than 1100 sites. We indicated a close correlation between the monoplastidy of vegetative tissue and the intensive RNA editing sites in the plastid genome in land plant lineages. Here, we proposed a hypothesis that the small population size of plastids in each vegetative cell of some early diverging land plants, including Takakia, might cause the frequent fixation of mutations in plastid genome through the intracellular genetic drift and that deleterious mutations might be continuously compensated by RNA editing during or following transcription.

Molecular phylogeny of the genus Fissidens (Fissidentaceae, Bryophyta) and a refinement of the infrageneric classification.

The genus Fissidens (ca. 440 spp.) is one of the phylogenetically poorly studied groups of mosses (Bryophyta). While various classifications of this genus have been proposed, no attempt at a classification of the genus based on combined molecular and morphological evidence has been made. Here, we present for the first time a comprehensive phylogenetic tree consisting of 50 representatives of Fissidens, reconstructed using sequence data from chloroplast rbcL and rps4 genes. Ancestral state reconstructions provide three clear apomorphies within Fissidens: peristome teeth, limbidium and chromosome number. Based on the phylogeny and morphological reassessment, we recognize three subgenera, Pachyfissidens, Neoamblyothallia, and Fissidens. Subgenus Neoamblyothallia consists of two sections: Neoamblyothallia and Crispidium. Subgenus Fissidens consists of five sections: Fissidens, Polypodiopsis, Aloma, Areofissidens, and Semilimbidium. High diversity of the most derived sect. Semilimbidium in the tropics suggests that the evolutionary history of the genus is through adaptation and diversification in tropical regions.

Comparative trial of two intravenous doses of granisetron (1 versus 3 mg) in the prevention of chemotherapy-induced acute emesis: a double-blind, randomized, non-inferiority trial.

PURPOSE: A single 3 mg or 40 µg/kg intravenous dose of granisetron combined with dexamethasone is routinely used in several countries, although the antiemetic guidelines have recommended granisetron at the dose of 1 mg or 10 µg/kg. A randomized, multicenter trial was conducted to determine the optimal intravenous granisetron dose, 1 or 3 mg, in cancer patients receiving emetogenic chemotherapy. METHODS: We enrolled 365 patients and randomly assigned them to receive intravenous granisetron 3 mg (3-mg group) or 1 mg (1-mg group), combined with dexamethasone at an adequate dose fixed as per the emetic risk category. The primary end point was the proportion of patients with a complete response during the first 24 h after chemotherapy. RESULTS: The study demonstrated that 1 mg of granisetron was not inferior in effect to 3 mg. For the primary end point, 359 patients were evaluable according to the modified intention-to-treat (ITT) analysis. Complete protection was achieved in the modified ITT population, 90.6% and 88.8% for the 3- and 1-mg groups, respectively (p < 0.01 for non-inferiority). CONCLUSIONS: This study showed that 1 mg granisetron is not inferior to 3 mg when both doses are combined with dexamethasone. Therefore, 1-mg dose of intravenous granisetron should be the recommended prophylactic regimen for the prevention of acute emesis.

Molecular phylogeny of Japanese Eleocharis (Cyperaceae) based on ITS sequence data, and chromosomal evolution.

ITS sequence data were used to estimate the phylogeny of 24 Japanese Eleocharis species and to make karyomorphological observations on 19 of these taxa. Two major clades were identified in Japanese Eleocharis molecular phylogenetic trees: (1) one including all species of section Limnochloa, and (2) another comprising two sections, Pauciflorae and Eleocharis. Phylogenetic analysis including both Japanese and North American species also shows strong support for monophyly of the Mutatae/ Limnochloa clade. The width of the spikelets in the species Mutatae/ Limnochloa is the same as that of the culms, indicating that the relative widths of spikelets and culms are useful characteristics for classification. Two major clades were supported by karyomorphological data. All taxa of section Limnochloa had very small chromosomes, while sections Pauciflorae and Eleocharis had large chromosomes. The basic chromosome number of sections Eleocharis and Pauciflorae is thought to be x=5. Chromosomal evolution in the genus Eleocharis with diffuse centromeric chromosomes may be caused by both aneuploidization and polyploidization. Our data suggest that a 3-bp insertion near the 3' end of the 5.8S gene is useful for intrageneric delimitations of the genus Eleocharis.