9 research outputs found
The Eurasian Modern Pollen Database (EMPD), version 2
The Eurasian (nee European) Modern Pollen Database (EMPD) was established in 2013 to provide a public database of high-quality modern pollen surface samples to help support studies of past climate, land cover, and land use using fossil pollen. The EMPD is part of, and complementary to, the European Pollen Database (EPD) which contains data on fossil pollen found in Late Quaternary sedimentary archives throughout the Eurasian region. The EPD is in turn part of the rapidly growing Neotoma database, which is now the primary home for global palaeoecological data. This paper describes version 2 of the EMPD in which the number of samples held in the database has been increased by 60% from 4826 to 8134. Much of the improvement in data coverage has come from northern Asia, and the database has consequently been renamed the Eurasian Modern Pollen Database to reflect this geographical enlargement. The EMPD can be viewed online using a dedicated map-based viewer at https://empd2.github.io and downloaded in a variety of file formats at https://doi.pangaea.de/10.1594/PANGAEA.909130 (Chevalier et al., 2019).Peer reviewe
The Eurasian Modern Pollen Database (EMPD), version 2
The Eurasian (née European) Modern Pollen Database (EMPD) was established in 2013 to provide a public database of high-quality modern pollen surface samples to help support studies of past climate, land cover, and land use using fossil pollen. The EMPD is part of, and complementary to, the European Pollen Database (EPD) which contains data on fossil pollen found in Late Quaternary sedimentary archives throughout the Eurasian region. The EPD is in turn part of the rapidly growing Neotoma database, which is now the primary home for global palaeoecological data. This paper describes version 2 of the EMPD in which the number of samples held in the database has been increased by 60 % from 4826 to 8134. Much of the improvement in data coverage has come from northern Asia, and the database has consequently been renamed the Eurasian Modern Pollen Database to reflect this geographical enlargement. The EMPD can be viewed online using a dedicated map-based viewer at https://empd2.github.io and downloaded in a variety of file formats at https://doi.pangaea.de/10.1594/PANGAEA.909130 (Chevalier et al., 2019)Swiss National Science Foundation | Ref. 200021_16959
Multilayer Capsules of Bovine Serum Albumin and Tannic Acid for Controlled Release by Enzymatic Degradation
With
the purpose to replace expensive and significantly cytotoxic positively
charged polypeptides in biodegradable capsules formed via Layer-by-Layer
(LbL) assembly, multilayers of bovine serum albumin (BSA) and tannic
acid (TA) are obtained and employed for encapsulation and release
of model drugs with different solubility in water: hydrophilic-tetramethylrhodamine-isothiocyanate-labeled
BSA (TRITC-BSA) and hydrophobic 3,4,9,10-tetra-(hectoxy-carbonyl)-perylene
(THCP). Hydrogen bonding is proposed to be predominant within thus
formed BSA/TA films. The TRITC-BSA-loaded capsules comprising 6 bilayers
of the protein and polyphenol are benchmarked against the shells composed
of dextran sulfate (DS) and poly-l-arginine (PARG) on degradability
by two proteolytic enzymes with different cleavage site specificity
(i.e., α-chymotrypsin and trypsin) and toxicity for murine RAW264.7
macrophage cells. Capsules of both types possess low cytotoxicity
taken at concentrations equal or below 50 capsules per cell, and evident
susceptibility to α-chymotrypsin resulted in release of TRITC-BSA.
While the BSA/TA-based capsules clearly display resistance to treatment
with trypsin, the assemblies of DS/PARG extensively degrade. Successful
encapsulation of THCP in the TRITC-BSA/TA/BSA multilayer is confirmed,
and the release of the model drug is observed in response to treatment
with α-chymotrypsin. The thickness, surface morphology, and
enzyme-catalyzed degradation process of the BSA/TA-based films are
investigated on a planar multilayer comprising 40 bilayers of the
protein and polyphenol deposited on a silicon wafer. The developed
BSA/TA-based capsules with a protease-specific degradation mechanism
are proposed to find applications in personal care, pharmacology,
and the development of drug delivery systems including those intravenous
injectable and having site-specific release capability
Biodegradable nanocarriers resembling extracellular vesicles deliver genetic material with the highest efficiency to various cell types
Abstract
Efficient delivery of genetic material to primary cells remains challenging. Here, efficient transfer of genetic material is presented using synthetic biodegradable nanocarriers, resembling extracellular vesicles in their biomechanical properties. This is based on two main technological achievements: generation of soft biodegradable polyelectrolyte capsules in nanosize and efficient application of the nanocapsules for co‐transfer of different RNAs to tumor cell lines and primary cells, including hematopoietic progenitor cells and primary T cells. Near to 100% efficiency is reached using only 2.5 × 10–4 pmol of siRNA, and 1 × 10–3 nmol of mRNA per cell, which is several magnitude orders below the amounts reported for any of methods published so far. The data show that biodegradable nanocapsules represent a universal and highly efficient biomimetic platform for the transfer of genetic material with the utmost potential to revolutionize gene transfer technology in vitro and in vivo