14 research outputs found
Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines
Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines
The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points
Automatic and precise simulation of multistage automatic cold-forging processes by combined analyses of two- and three-dimensional approaches
No evidence of improved efficacy of covered stents over uncovered stents in percutaneous palliation of malignant hilar biliary obstruction: results of a prospective randomized trial
Age and Sex Ratios in a High-Density Wild Red-Legged Partridge Population
The dynamics of a wild red-legged partridge population were examined over a 14-year period in Spain to identify patterns in age and sex ratios in relation to weather parameters, and to assess the importance of these parameters in population dynamics and management. The results gave age ratios of 1.07 (but 2.13 in July counts), juvenile sex ratios of 1.01 and adult sex ratios of 1.47. Overall, 12% more females were hatched and female juvenile mortality was 7.3% higher than in males. Sex differential mortality explains the 19.2% deficit in adult females, which are more heavily predated than males during the breeding
period. Accordingly, age ratios are dependent on sex ratios and both are density dependent. Over time, ratios and density changes appear to be influenced by weather and management. When the habitat is well conserved, partridge population dynamics can be explained by a causal chain: weather operates on net primary production, thereby affecting partridge reproduction and predation and, as a result, age and sex ratios in the October population. A reduction in the impact of predation (i.e. the effects of ground predators on eggs, chicks and breeding females) is the key factor to improve the conservation of partridge populations and associated biological processes
Cenomanian-Turonian transition in a shallow water sequence of the Sinai, Egypt
Environmental and depositional changes across the Late Cenomanian
oceanic anoxic event (OAE2) in the Sinai, Egypt, are examined based on
biostratigraphy, mineralogy, delta(13)C values and phosphorus analyses.
Comparison with the Pueblo, Colorado, stratotype section reveals the
Whadi El Ghaib section as stratigraphically complete across the late
Cenomanian-early Turonian. Foraminifera are dominated by high-stress
planktic and benthic assemblages characterized by low diversity,
low-oxygen and low-salinity tolerant species, which mark shallow-water
oceanic dysoxic conditions during OAE2. Oyster biostromes suggest
deposition occurred in less than 50 m depths in low-oxygen, brackish,
and nutrient-rich waters. Their demise prior to the peak delta(13)C
excursion is likely due to a rising sea-level. Characteristic OAE2
anoxic conditions reached this coastal region only at the end of the
delta(13)C plateau in deeper waters near the end of the Cenomanian.
Increased phosphorus accumulations before and after the delta(13)C
excursion suggest higher oxic conditions and increased detrital input.
Bulk-rock and clay mineralogy indicate humid climate conditions,
increased continental runoff and a rising sea up to the first delta(13)C
peak. Above this interval, a dryer and seasonally well-contrasted
climate with intermittently dry conditions prevailed. These results
reveal the globally synchronous delta(13)C shift, but delayed effects of
OAE2 dependent on water depth