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Biomedical subjects

R A Gill

Publications and source records attributed to R A Gill.

9 recordsLinked to original sources
PubMed2004

Contamination of surface soils, river water and sediments by trace metals from copper processing industry in the Churnet River Valley, Staffordshire, UK.

The impacts of a functional and a demolished copper processing works on the aquatic and terrestrial environment in the vicinity of the works was investigated by determining the levels of selected trace metals in river water, river sediments, channel margin sediments and overbank soils. Samples were taken at five sites within an area of the Churnet Valley in Staffordshire, where the River Churnet flows through the two works. Analysis of river water samples by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) has shown that only copper is present above background levels considered to typify uncontaminated rivers. Analysis of river sediments, channel margin sediments and overbank soils by nitric-perchloric acid digestion and Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) analysis has indicated contamination by arsenic, cadmium and copper in the vicinity of both works. Arsenic and copper are deposited primarily within the aquatic environment, although some contamination of the terrestrial environment by copper is also observed. Cadmium is deposited primarily within the terrestrial environment. The deposition of arsenic and copper in river and channel margin sediments respectively is also related to current and historical contamination.

Arsenic↗
PubMed2003

The relationship between epilithic periphyton (biofilm) bound metals and metals bound to sediments in freshwater systems.

Surficial sediments and epilithic periphyton (biofilm) were sampled from six sites on the River Churnet and five sites on the River Manifold in Staffordshire and analysed for cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn). The sites demonstrated a wide range of sediment trace metal concentrations determined by inductively coupled plasma optical emission spectrometry (ICP-OES) and atomic absorbtion spectroscopy (AAS). Biofilm was removed from the substrate using physical abrasion and 0.005 M ethylenediaminoethanetetra-acetic acid (EDTA) extractant. The European Standards, Measurements and Testing Programmes (BCR) operationally defined geochemical speciation scheme was used to determine the exchangeable, acid soluble fraction of the sediments. Significant positive correlations were determined between the EDTA extractable biofilm and the exchangeable sediment fraction for Cd, Cu and Zn but not for Pb. Natural epilithic periphyton may be a potential metal biomonitor particularly of Cu, Cd and Zn in aquatic systems and provide supporting information in relation to potential sediment toxicity.

Biofilms↗
PubMed2003

Preliminary evidence for the metabolism of benzo(a) pyrene by Plantago lanceolata.

Polycyclic aromatic hydrocarbons (PAHs) have long been recognised as potential carcinogens in animals in which biotransformation into reactive metabolites can lead to DNA damage. In animals PAHs metabolism mainly occurs in hepatic microsomes and is associated with the cytochrome p-450 mediated mixed functional oxidase (MFO) system. PAH metabolism in plants has been shown to occur via a similar enzyme system, but has received relatively little attention. This study is looking at how the plant species Plantago lanceolata metabolizes benzo(a)pyrene (B(a)P), which is one of the PAHs whose metabolism has been studied extensively in animals. The aim of the work is to establish firstly that the B(a)P is taken up and secondly that it is biotransformed by the plant to products possibly similar to those found in animals. This work is achieved by using C-14-B(a)P along with whole body autoradiography, scintillation analysis and chromatography techniques to locate the B(a)P and its metabolites.

Benzo(a)pyrene↗
PubMed1983

Aminopyrine breath test predicts surgical risk for patients with liver disease.

To determine whether the [14C] aminopyrine breath test (ABT) predicts surgical risk in patients with liver disease, it was obtained prior to various surgeries in 38 patients with known or suspected liver disease. A modified Child's classification was also determined. Six of the seven operative deaths (three Child's A, two B, two C) had ABTs less than 2.3%, while 30 of 31 survivors (24 Child's A, seven B) had ABTs greater than 2.3% (p less than 0.000018). Seven of the 16 patients with normal ABTs had biopsy-proven cirrhosis and had postoperative courses indistinguishable from the remainder of the group. We conclude that surgery in patients with ABTs less than 2.3% is associated with extremely high mortality. In addition, cirrhotics with normal ABTs tolerate elective surgery well.

Adult↗
PubMed1982

Hepatic veno-occlusive disease caused by 6-thioguanine.

Clinically reversible veno-occlusive disease of the liver developed in a 23-year-old man with acute lymphocytic leukemia after 10 months of maintenance therapy with 6-thioguanine. Serial liver biopsies showed the development and resolution of intense sinusoidal engorgement. Although this disease was clinically reversible, some subintimal fibrosis about the terminal hepatic veins persisted. This case presented a unique opportunity to observe the histologic features of clinically reversible hepatic veno-occlusive disease over time, and may be the first case of veno-occlusive related solely to 6-thioguanine.

Adult↗