61 research outputs found
The RootScope: A Simple High-Throughput Screening System For Quantitating Gene Expression Dynamics In Plant Roots
Background: High temperature stress responses are vital for plant survival. The mechanisms that plants use to sense high temperatures are only partially understood and involve multiple sensing and signaling pathways. Here we describe the development of the RootScope, an automated microscopy system for quantitating heat shock responses in plant roots.Results: The promoter of Hsp17.6 was used to build a Hsp17.6(p):GFP transcriptional reporter that is induced by heat shock in Arabidopsis. An automated fluorescence microscopy system which enables multiple roots to be imaged in rapid succession was used to quantitate Hsp17.6p: GFP response dynamics. Hsp17.6(p):GFP signal increased with temperature increases from 28 degrees C to 37 degrees C. At 40 degrees C the kinetics and localization of the response are markedly different from those at 37 degrees C. This suggests that different mechanisms mediate heat shock responses above and below 37 degrees C. Finally, we demonstrate that Hsp17.6(p):GFP expression exhibits wave like dynamics in growing roots.Conclusions: The RootScope system is a simple and powerful platform for investigating the heat shock response in plants
Gas chromatographic electron capture negative ionization mass spectrometric (GC/ECNI/MS) determination of unique fluorinated compounds in the sediments of Lake Ontario and the effect of high-boiling alcohols (as injection solvents) on chromatographic behaviour of polycyclic aromatic hydrocarbons in gas chromatography
Part I - Fluorinated Compounds
A method has been developed for the extraction, concentration, and
determination of two unique fluorinated compounds from the sediments of Lake
Ontario. These compounds originated from a common industrial landfill, and
have been carried to Lake Ontario by the Niagara River. Sediment samples from
the Mississauga basin of Lake Ontario have been evaluated for these compounds
and a depositional trend was established. The sediments were extracted by
accelerated solvent extraction (ASE) and then underwent clean-up, fractionation,
solvent exchange, and were concentrated by reduction under nitrogen gas. The
concentrated extracts were analyzed by gas chromatography - electron capture
negative ionization - mass spectrometry.
The depositional profile determined here is reflective of the operation of the
landfill and shows that these compounds are still found at concentrations well
above background levels. These increased levels have been attributed to physical
disturbances of previously deposited contaminated sediments, and probable
continued leaching from the dumpsite.
Part II - Polycyclic Aromatic Hydrocarbons
Gas chromatography/mass spectrometry is the most common method for
the determination of polycyclic aromatic hydrocarbons (PAHs) from various
matrices. Mass discrimination of high-boiling compounds in gas chromatographic
methods is well known. The use of high-boiling injection solvents shows
substantial increase in the response of late-eluting peaks. These solvents have an
increased efficiently in the transfer of solutes from the injector to the analytical
column. The effect of I-butanol, I-pentanol, cyclopentanol, I-hexanol, toluene
and n-octane, as injection solvents, was studied.
Higher-boiling solvents yield increased response for all PAHs. I -Hexanol
is the best solvent, in terms of P AH response, but in this solvent P AHs were more
susceptible to chromatographic problems such as peak splitting and tailing.
Toluene was found to be the most forgiving solvent in terms of peak symmetry
and response. It offered the smallest discrepancies in response, and symmetry
over a wide range of initial column temperatures
Barriers to Creutzfeldt-Jakob Disease Autopsies, California
Creutzfeldt-Jakob disease (CJD) surveillance relies on autopsy and neuropathologic evaluation. The 1990–2000 CJD autopsy rate in California was 21%. Most neurologists were comfortable diagnosing CJD (83%), but few pathologists felt comfortable diagnosing CJD (35%) or performing autopsy (29%). Addressing obstacles to autopsy is necessary to improve CJD surveillance
Communications Biophysics
Contains research objectives and reports on six research projects split into three sections.National Institutes of Health (Grant 5 P01 NS13126-07)National Institutes of Health (Training Grant 5 T32 NS07047-05)National Institutes of Health (Training Grant 2 T32 NS07047-06)National Science Foundation (Grant BNS 77-16861)National Institutes of Health (Grant 5 R01 NS1284606)National Institutes of Health (Grant 5 T32 NS07099)National Science Foundation (Grant BNS77-21751)National Institutes of Health (Grant 5 R01 NS14092-04)Gallaudet College SubcontractKarmazin Foundation through the Council for the Arts at M.I.T.National Institutes of Health (Grant 1 R01 NS1691701A1)National Institutes of Health (Grant 5 R01 NS11080-06)National Institutes of Health (Grant GM-21189
Communications Biophysics
Contains reports on ten research projects.National Institutes of Health (Grant 5 P01 NS13126)National Institutes of Health (Training Grant 5 T32 NS0704)National Science Foundation (Grant BNS80-06369)National Institutes of Health (Grant 5 R01 NS11153)National Science Foundation (Grant BNS77-16861)National Institutes of Health (Grant 5 RO1 NS12846)National Science Foundation (Grant BNS77-21751)National Institutes of Health (Grant 1 P01 NS14092)Karmazin Foundation through the Council for the Arts at MITNational Institutes of Health (Fellowship 5 F32 NS06386)National Science Foundation (Fellowship SP179-14913)National Institutes of Health (Grant 5 RO1 NS11080
Communications Biophysics
Contains reports on nine research projects split into four sections.National Institutes of Health (Grant 5 PO1 NS13126)National Institutes of Health (Grant 5 KO4 NS00113)National Institutes of Health (Training Grant 5 T32 NS07047)National Institutes of Health (Training Grant 1 T32 NS07099)National Science Foundation (Grant BNS77-16861)National Institutes of Health (Grant 5 ROI NS10916)National Institutes of Health (Grant 5 RO1 NS12846)National Science Foundation (Grant BNS77-21751)National Institutes of Health (Grant 1 RO1 NS14092)Edith E. Sturgis FoundationHealth Sciences FundNational Institutes of Health (Grant 2 R01 NS11680)National Institutes of Health (Fellowship 5 F32 NS05327)National Institutes of Health (Grant 2 ROI NS11080)National Institutes of Health (Training Grant 5 T32 GM07301
- …