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G Wilmoth

Publications and source records attributed to G Wilmoth.

4 recordsLinked to original sources
PubMed2000

Active Fe-containing superoxide dismutase and abundant sodF mRNA in Nostoc commune (Cyanobacteria) after years of desiccation.

Active Fe-superoxide dismutase (SodF) was the third most abundant soluble protein in cells of Nostoc commune CHEN/1986 after prolonged (13 years) storage in the desiccated state. Upon rehydration, Fe-containing superoxide disumutase (Fe-SOD) was released and the activity was distributed between rehydrating cells and the extracellular fluid. The 21-kDa Fe-SOD polypeptide was purified, the N terminus was sequenced, and the data were used to isolate sodF from the clonal isolate N. commune DRH1. sodF encodes an open reading frame of 200 codons and is expressed as a monocistronic transcript (of approximately 750 bases) from a region of the genome which includes genes involved in nucleic acid synthesis and repair, including dipyrimidine photolyase (phr) and cytidylate monophosphate kinase (panC). sodF mRNA was abundant and stable in cells after long-term desiccation. Upon rehydration of desiccated cells, there was a turnover of sodF mRNA within 15 min and then a rise in the mRNA pool to control levels (quantity of sodF mRNA in cells in late logarithmic phase of growth) over approximately 24 h. The extensive extracellular polysaccharide (glycan) of N. commune DRH1 generated superoxide radicals upon exposure to UV-A or -B irradiation, and these were scavenged by SOD. Despite demonstrated roles for the glycan in the desiccation tolerance of N. commune, it may in fact be a significant source of damaging free radicals in vivo. It is proposed that the high levels of SodF in N. commune, and release of the enzyme from dried cells upon rehydration, counter the effects of oxidative stress imposed by multiple cycles of desiccation and rehydration during UV-A or -B irradiation in situ.

Amino Acid Sequence↗
PubMed1997

Use of intraperitoneal 5-fluorouracil and chlorhexidine for prevention of recurrence of perforated colorectal carcinoma in a rat model.

PURPOSE: Colorectal cancer is a prevalent and mortal disease, resulting in nearly 55,000 deaths in the United States annually. Preoperative or intraoperative spillage of tumor cells because of perforation occurs in up to 10 percent of cases. When this spillage occurs, the chance of recurrence and death is dramatically increased. METHODS: In an effort to reduce the chance of recurrence and death, we used a rat model to evaluate the efficacies of intraperitoneal 5-fluorouracil and chlorhexidine in reducing the incidence of recurrence. Rats were injected with 10 mg/kg azoxymethane subcutaneously weekly for 12 weeks to induce colorectal cancers. At 20 weeks, subtotal colectomies were performed on rats with colorectal tumors and without peritoneal implants or liver metastases. At the time of surgery, a cut portion of the tumor was placed in the abdomen for 30 minutes; the rats then randomly received peritoneal irrigation with 5-fluorouracil, chlorhexidine, or sterile water (control). Eight weeks postoperatively a necropsy was performed. At that time, obvious and suspected recurrences and the anastomotic area were sampled for histologic evaluation. RESULTS: Significant differences were seen with chlorhexidine vs. water for gross tumor (P = 0.05) and microscopic tumor (P < 0.05). 5-Fluorouracil showed a greater rate of abscess formation vs. both control and chlorhexidine (P > 0.05). CONCLUSIONS: Use of chlorhexidine intraperitoneal therapy at the time of the operation for perforated colorectal cancer significantly decreases the frequency of gross tumor recurrence but not total recurrences. Intraperitoneal 5-fluorouracil does not significantly decrease recurrence and may increase the risk of abscess when used intraoperatively.

Animals↗
PubMed1996

Rectal carcinoma: are we making a difference?

Evaluation of preliminary results at our institution revealed an improvement in survival of patients treated for rectal cancer from 1950-1988. A study was conducted to analyze responsible factors. A total of 335 patients with accurate staging and follow up for at least 5 years or until death were reviewed retrospectively. Of the 335 patients, 295 (88%) were treated by surgical resection, abdominal perineal resection (APR) (n=179), and anterior resections (n=105), the most common procedures. Operative mortality for patients with curable disease (n=188) was 18 per cent (n=34), which has significantly decreased from 24 per cent (n=28) (1950-1969) to 8 per cent (n=6) (1970-1988), (P < 0.01). Operative mortality for APR and anterior resection was 22 per cent (n=29) and 8 per cent (n=5), respectively. Mortality for APR decreased from 28 per cent (1950-1969) to 10 per cent (1970-1988) (P < 0.02) accounting for most of the improvement. Of the 335 patients, 142 (42%) presented with stage IV disease, which decreased from 54 per cent (n=47) (1950s) to 22 per cent (n=10) (1980s), P < 0.01. The overall 5-year survival was 19 per cent (n=64), with a corresponding increase per decade from 13 per cent (1950s) to 43 per cent (1980s), (P < 0.001). Of the remaining 188 patients, 41 had involved surgical margins and decreased 5-year survival of 8 per cent when compared to patients with clear surgical margins (37%) P < 0.01). Multifactor analysis revealed that stage of disease at presentation, involved surgical margins, and operative mortality were significant independent variables. Earlier stage at presentation and improved operative management increased the survival of patients with rectal cancer at our institution.

Cause of Death↗