409 research outputs found
De la rencontre et de l’oubli : les livres entre non-lecture et délecture. L’exemple de Nadja d’André Breton
Changes in matrix gene and protein expressions after single or repeated exposure to one minimal erythemal dose of solar-simulated radiation in human skin in vivo
peer reviewedaudience: researcher, professionalDamage to the skin extracellular matrix (ECM) is the hallmark of long-term exposure to solar UV radiation. The aim of our study was to investigate the changes induced in unexposed human skin in vivo after single or repeated (five times a week for 6 weeks) exposure to I minimal erythemal dose (MED) of UV solar-simulated radiation. Morphological and biochemical analyses were used to evaluate the structural ECM components and the balance between the degrading enzymes and their physiologic inhibitors. A three-fold increase in matrix metalloproteinase 2 messenger RNA (mRNA) (P < 0.02, unexposed versus exposed) was observed after both single and repeated exposures. Fibrillin 1 mRNA level was increased by chronic exposure (P < 0.02) and unaltered by a single MED. On the contrary, a single MED significantly enhanced mRNA levels of interleukin-la (IL-1alpha), IL-1beta (P < 0.02) and plasminogen activator inhibitor-1 (P < 0.05). Immunohistochemistry demonstrated a significant decrease in Type-I procollagen localized just below the dermal-epidermal junction in both types of exposed sites. At the same location, the immunodetected tenascin was significantly enhanced, whereas a slight increase in Type-III procollagen deposits was also observed in chronically exposed areas. Although we were unable to observe any change in elastic fibers in chronically exposed buttock skin, a significant increase in lysozyme and alpha-1 antitrypsin deposits on these fibers was observed. These results demonstrate the existence of a differential regulation, after chronic exposure compared with an acute one, of some ECM components and inflammatory mediators
Nuevo esquema estratigráfico para los depósitos marinos mio-pliocenos del área de Navidad [33°00'-34°30'S].Chile Central
Phylogenetic placement of environmental sequences using taxonomically reliable databases helps to rigorously assess dinophyte biodiversity in Bavarian lakes (Germany).
1. Reliable determination of organisms is a prerequisite to explore their spatial
and temporal occurrence and to study their evolution, ecology, and dispersal. In
Europe, Bavaria (Germany) provides an excellent study system for research on the
origin and diversification of freshwater organisms including dinophytes, due to
the presence of extensive lake districts and ice age river valleys. Bavarian freshwater
environments are ecologically diverse and range from deep nutrient‐poor
mountain lakes to shallow nutrient‐rich lakes and ponds.
2. We obtained amplicon sequence data (V4 region of small subunit‐rRNA, c. 410 bp
long) from environmental samples collected at 11 sites in Upper Bavaria. We
found 186 operational taxonomic units (OTUs) associated with Dinophyceae that
were further classified by means of a phylogenetic placement approach.
3. The maximum likelihood tree inferred from a well‐curated reference alignment comprised
a systematically representative set of 251 dinophytes, covering the currently
known molecular diversity and OTUs linked to type material if possible. Environmental
OTUs were scattered across the reference tree, but accumulated mostly in freshwater
lineages, with 79% of OTUs placed in either Apocalathium, Ceratium, or Peridinium,
the most frequently encountered taxa in Bavaria based on morphology.
4. Twenty‐one Bavarian OTUs showed identical sequences to already known and
vouchered accessions, two of which are linked to type material, namely Palatinus
apiculatus and Theleodinium calcisporum. Particularly within Peridiniaceae, delimitation
of Peridinium species was based on the intraspecific sequence variation.
5. Our approach indicates that high‐throughput sequencing of environmental samples
is effective for reliable determination of dinophyte species in Bavarian lakes.
We further discuss the importance of well‐curated reference databases that remain
to be developed in the future
Strict selection alone of patients undergoing liver transplantation for hilar cholangiocarcinoma is associated with improved survival
Liver transplantation for hilar cholangiocarcinoma (hCCA) has regained attention since the Mayo Clinic reported their favorable results with the use of a neo-adjuvant chemoradiation protocol. However, debate remains whether the success of the protocol should be attributed to the neo-adjuvant therapy or to the strict selection criteria that are being applied. The aim of this study was to investigate the value of patient selection alone on the outcome of liver transplantation for hCCA. In this retrospective study, patients that were transplanted for hCCA between1990 and 2010 in Europe were identified using the European Liver Transplant Registry (ELTR). Twenty-one centers reported 173 patients (69%) of a total of 249 patients in the ELTR. Twenty-six patients were wrongly coded, resulting in a study group of 147 patients. We identified 28 patients (19%) who met the strict selection criteria of the Mayo Clinic protocol, but had not undergone neo-adjuvant chemoradiation therapy. Five-year survival in this subgroup was 59%, which is comparable to patients with pretreatment pathological confirmed hCCA that were transplanted after completion of the chemoradiation protocol at the Mayo Clinic. In conclusion, although the results should be cautiously interpreted, this study suggests that with strict selection alone, improved survival after transplantation can be achieved, approaching the Mayo Clinic experience
Criptógamos do Parque Estadual das Fontes do Ipiranga, São Paulo, SP. Algae, 42: Bacillariophyceae (Surirellales)
(Table 3) Occurrence of upper Oligocene to lower Miocene diatom species in ODP Hole 121-758A
species abundance: A = abundant (at least 20 specimens are presented in one horizontal traverse at 500 X), C = common (19-3 specimens), F = few (1-2 specimens), R = rare (less than 1 specimen), - = absent, ? = questionabl
(Table 2) Depth and age of several diatom datums for the upper Pliocene to Quaternary interval of ODP Hole 121-758A
(Table 2) Depth and age of several diatom datums for the upper Pliocene to Quaternary interval of ODP Hole 121-758
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