34 research outputs found
The genera Melanothamnus Bornet & Falkenberg and Vertebrata S.F. Gray constitute well-defined clades of the red algal tribe Polysiphonieae (Rhodomelaceae, Ceramiales).
Polysiphonia is the largest genus of red algae, and several schemes subdividing it into smaller taxa have been proposed since its original description. Most of these proposals were not generally accepted, and currently the tribe Polysiphonieae consists of the large genus Polysiphonia (190 species), the segregate genus Neosiphonia (43 species), and 13 smaller genera (< 10 species each). In this paper, phylogenetic relationships of the tribe Polysiphonieae are analysed, with particular emphasis on the genera Carradoriella, Fernandosiphonia, Melanothamnus, Neosiphonia, Polysiphonia sensu stricto, Streblocladia and Vertebrata. We evaluated the consistency of 14 selected morphological characters in the identified clades. Based on molecular phylogenetic (rbcL and 18S genes) and morphological evidence, two speciose genera are recognized: Vertebrata (including the type species of the genera Ctenosiphonia, Enelittosiphonia, Boergeseniella and Brongniartella) and Melanothamnus (including the type species of the genera Fernandosiphonia and Neosiphonia). Both genera are distinguished from other members of the Polysiphonieae by synapomorphic characters, the emergence of which could have provided evolutionarily selective advantages for these two lineages. In Vertebrata trichoblast cells are multinucleate, possibly associated with the development of extraordinarily long, photoprotective, trichoblasts. Melanothamnus has 3-celled carpogonial branches and plastids lying exclusively on radial walls of the pericentral cells, which similarly may improve resistance to damage caused by excessive light. Other relevant characters that are constant in each genus are also shared with other clades. The evolutionary origin of the genera Melanothamnus and Vertebrata is estimated as 75.7-95.78 and 90.7-138.66 Ma, respectively. Despite arising in the Cretaceous, before the closure of the Tethys Seaway, Melanothamnus is a predominantly Indo-Pacific genus and its near-absence from the northeastern Atlantic is enigmatic. The nomenclatural implications of this work are that 46 species are here transferred to Melanothamnus, six species are transferred to Vertebrata and 13 names are resurrected for Vertebrata
Nuclear receptor corepressors
The ability of NR LBDs to transfer repression function to a heterologous DNA binding domain, and the cross-squelching of repression by untethered LBDs, has suggested that repression is mediated by interactions with putative cellular corepressor proteins. The yeast-two hybrid screen for protein interactors has proven to be the key to the isolation and characterization of corepressors. This short review will focus on N-CoR and SMRT
High temperature thermal stability of pure copper and copper - carbon nanotube composites consolidated by High Pressure Torsion
The thermal stability of ultrafine-grained (UFG) microstructures in pure copper samples and copper–car-
bon nanotube (CNT) composites processed by High Pressure Torsion (HPT) was compared. The UFG
microstructure in the sample consolidated from pure Cu powder exhibited better stability than that
developed in a casted Cu specimen. The addition of CNTs to the Cu powder further increased the stability
of the UFG microstructure in the consolidated Cu matrix by hindering recrystallization, however it also
yielded a growing porosity and cracking during annealing. It was shown that the former effect was stron-
ger than the latter one, therefore the addition of CNTs to Cu has an overall benefit to the hardness in the
temperature range between 300 and 1000 K. A good agreement between the released heat measured dur-
ing annealing and the calculated stored energy was found for all samples
Microstructure and thermal stability of copper - carbon nanotube composites consolidated by High Pressure Torsion
Blends of Cu powders and 3 vol. % carbon nanotubes (CNTs), and an additional sample
from pure Cu powder were consolidated by High Pressure Torsion (HPT) at room temperature (RT)
and 373 K. The grain size, the lattice defect densities as well as the hardness of the pure and
composite materials were determined. Due to the pinning effect of CNTs, the dislocation density is
about three times larger, while the grain size is about half of that obtained in the sample
consolidated from the pure Cu powder. The increase of the HPT-processing temperature from RT to
373 K resulted in only a slight increase of the grain size in the Cu-CNT composite while the
dislocation density and the twin boundary frequency were reduced significantly. The flow stress
obtained experimentally agrees well with the value calculated by the Taylor-formula indicating that
the strength in both pure Cu and Cu-CNT composites is determined mainly by the interaction
between dislocations. The addition of CNTs to Cu yields a significantly better thermal stability of
the UFG matrix processed by HPT
Is there a real role of postoperative antibiotic administration for mild-moderate acute cholecystitis? A prospective randomized controlled trial
Antitumor effect of intratumoral administration of dendritic cell combination with vincristine chemotherapy in a murine fibrosarcoma model
A new antitumor therapeutic strategy
utilizing the combined effect of chemotherapy and DC
(dendritic cell)-based immunotherapy was designed, and
the effect of intratumoral injections of unpulsed,
immature DCs was evaluated after in vivo pretreatment
of vincristine on tumor growth in a murine fibrosarcoma
tumor model.
Vincristine exerted a much more potent
apoptosis/necrosis-inducing effect on MCA-102 tumor
cells than on DCs both in vitro and in vivo. Moreover,
CD11c, CD40, CD80 and CD86 molecules on DCs were
not downregulated after treatment with vincristine either
in vitro or in vivo. The growth of tumor significantly
regressed in the group which received the combined
vincristine chemotherapy with intratumoral
administration of DCs in contrast to the untreated group,
the group treated with DCs alone, and the group treated
with vincristine alone. In particular, an upregulated
expression of CD40, CD80 and CD86 molecules on DCs
was found in the combination treatment group.
Furthermore, the number of CD4+ and CD8+ T cells and
the staining intensity of their CD4 and CD8 surface
molecules also increased after the combination
treatment.
Therefore, our results indicate the feasibility of this
combination therapy with vincristine chemotherapy and
DC-based immunotherapy as an efficient antitumor
strategy for the treatment of fibrosarcoma