2 research outputs found
Tile Drainage and Anthropogenic Land Use Contribute to Harmful Algal Blooms and Microbiota Shifts in Inland Water Bodies
Freshwater
harmful algal blooms (HABs), driven by nutrient inputs
from anthropogenic sources, pose unique risks to human and ecological
health worldwide. A major nutrient contributor is agricultural land
use, specifically tile drainage discharge. Small lakes and ponds are
at elevated risk for HAB appearance, as they are uniquely sensitive
to nutrient input. HABs introduce exposure risk to microcystin (MC),
hepatotoxic and potentially carcinogenic cyanotoxins. To investigate
the impact of anthropogenic land use on small lakes and ponds, 24
sites in central Ohio were sampled over a 3-month period in late summer
of 2015. MC concentration, microbial community structure, and water
chemistry were analyzed. Land use intensity, including tile drainage
systems, was the driver of clustering in principle component analysis,
ultimately contributing to nutrient deposition, a driver of HABs.
Relative abundance of HAB-forming genera was correlated with elevated
concentrations of nitrate and soluble reactive phosphate. One location
(FC) showed MC concentrations exceeding 875 μg/L and large community
shifts in ciliates (Oligohymenophorea) associated with hypoxic conditions.
The prokaryotic community at FC was dominated by <i>Planktothrix</i> sp. These results demonstrate the impact of HABs in small lakes
and ponds, and that prevailing issues extend beyond cyanotoxins, such
as cascading impacts on other trophic levels
H‑Gemcitabine: A New Gemcitabine Prodrug for Treating Cancer
In this report, we present a new strategy for targeting
chemotherapeutics
to tumors, based on targeting extracellular DNA. A gemcitabine prodrug
was synthesized, termed H-gemcitabine, which is composed of Hoechst
conjugated to gemcitabine. H-gemcitabine has low toxicity because
it is membrane-impermeable; however, it still has high tumor efficacy
because of its ability to target gemcitabine to E-DNA in tumors. We
demonstrate here that H-gemcitabine has a wider therapeutic window
than free gemcitabine