Biomedical subjects

A M Easson

Publications and source records attributed to A M Easson.

6 recordsLinked to original sources

PubMed2001

Discussion of death and dying in surgical textbooks.

BACKGROUND: Quality end-of-life care is an increasing concern for the public and the medical profession. Surgical textbooks could serve as an important educational and reference resource to improve this care. METHODS: Four general surgical textbooks were scored for helpful information on death and dying for eight surgical diseases. For each disease, nine content domains related to care of the dying patient were evaluated. Three texts included a chapter on cancer that was evaluated separately. RESULTS: Disease epidemiology, prognosis/prevention, progression, and medical interventions were generally well discussed in all textbooks. However, little helpful information was provided with regards to breaking bad news/advanced care planning, mode of death, treatment decision-making, effect on family/surgeon, and symptom management. Cancer chapters also addressed only a few of these concerns. CONCLUSION: Death and the dying patient are sufficiently frequent in surgical practice that it would be appropriate to increase the amount of information provided.

Bibliometrics↗

PubMed2001

Palliative general surgical procedures.

Two types of procedure may be indicated in incurable patients. The first is palliative, in which the goal of intervention is relief of symptoms. The second type is supportive, where the procedure is a technical intervention done as part of a multidisciplinary treatment plan. The most minimally invasive but effective procedure is chosen. Procedures are categorized by the type of symptom the procedure is intended to relieve. This article emphasizes the principles involved in patient selection and outcome assessment in order to identify areas where more research is needed.

General Surgery↗

PubMed2000

Tumor-influenced amino acid transport activities in zonal-enriched hepatocyte populations.

Cancer influences hepatic amino acid metabolism in the host. To further investigate this relationship, the effects of an implanted fibrosarcoma on specific amino acid transport activities were measured in periportal (PP)- and perivenous (PV)-enriched rat hepatocyte populations. Na(+)-dependent glutamate transport rates were eightfold higher in PV than in PP preparations but were relatively unaffected during tumor growth. System N-mediated glutamine uptake was 75% higher in PV than in PP preparations and was stimulated up to twofold in both regions by tumor burdens of 9 +/- 4% of carcass weight compared with hepatocytes from pair-fed control animals. Excessive tumor burdens (26 +/- 7%) resulted in hypophagia, loss of PV-enriched system N activities, and reduced transporter stimulation. Conversely, saturable arginine uptake was enhanced fourfold in PP preparations and was induced twofold only after excessive tumor burden. These data suggest that hepatic amino acid transporters are differentially influenced by cancer in a spatial and temporal manner, and they represent the first report of reciprocal zonal enrichment of system N and saturable arginine uptake in the mammalian liver.

Amino Acids↗

PubMed2000

Ontario familial colon cancer registry: methods and first-year response rates.

The Ontario Familial Colon Cancer Registry (OFCCR) is a novel registry that collects family history information, epidemiologic data, blood samples and tumour specimens from a population-based sample of colorectal cancer patients and their families. Families are classified as either high familial risk, intermediate familial/other risk or low (sporadic) risk for colorectal cancer. Obtaining high response rates in genetic family studies is especially challenging because of both the time commitment required and issues of confidentiality. The first-year response rate was 61%, resulting in 1,395 participating probands. In an attempt to assess potential response bias, we compared participants with non-participants. The age and sex of participants did not differ from non-participating probands; however, cases in rural areas were somewhat more likely to participate. To date, 57% of 1,587 relatives participated; females were more likely to participate, and relatives of low familial risk were least likely to participate. The OFCCR is an excellent resource that will facilitate the study of genetic and environmental factors associated with colorectal cancer.

Adult↗

PubMed1998

Effects of endotoxin challenge on hepatic amino acid transport during cancer.

BACKGROUND: The hepatic uptake of amino acids is increased in both sepsis and cancer, and this response appears to be both global and essential in the catabolic host. Because immunocompromised cancer patients are susceptible to episodes of gram-negative sepsis, we examined the capacity of hepatocytes from normal and tumor-influenced livers to respond to the additional challenge of endotoxemia via increases in the Na+-dependent uptake of glutamine and zwitterionic amino acids by System N and System A, respectively. MATERIALS AND METHODS: Fischer 344 rats were implanted with methylcholanthrene-induced fibrosarcomas. Control rats were sham-operated and pair-fed. Animal pairs (tumor burden = 8-32% carcass weight) were injected intraperitoneally with either Escherichia coli endotoxin (10 mg/kg) or PBS, and after 4 h, hepatocytes were isolated from the livers of the animals via collagenase perfusion and placed in primary culture. Three hours later, amino acid transport rates were measured using radiolabeled glutamine for System N and alpha-methylaminoisobutyric acid (MeAIB), a nonmetabolizable substrate specific for System A. RESULTS: Cancer-independent of tumor size-and endotoxin each elicited similar 1.5- to 2-fold inductions of System N activity. When combined, their effects were additive rather than synergistic. In contrast, endotoxin induced an insignificant increase in System A activity, whereas cancer stimulated this carrier 2-fold in either the absence or the presence of endotoxin. CONCLUSIONS: The primary glutamine and alanine carriers in hepatocytes are differentially influenced during catabolic states, and the tumor-influenced liver is competent to further increase glutamine uptake in response to additional catabolic insults.

Amino Acids↗

PubMed1996

Calcification in colorectal hepatic metastases correlates with longer survival.

BACKGROUND: Calcification occurs in 12-27% of hepatic colorectal metastases, but its clinical significance and its influence on prognosis are unknown. METHODS: All patients diagnosed with colorectal liver metastases at the Ottawa Regional Cancer Center in 1991 (n = 97), as well as those enrolled in chemotherapy trials in 1990-1992 (n = 51), were entered into a retrospective cohort study. Thirty-six patients were excluded due to inadequate follow-up. In the remaining 112, abdominal CT scans and/or ultrasound examinations were used to determine the presence of calcification. Charts were reviewed for variables, including primary tumour pathology, amount of liver involvement by tumour (< 25%, 25-50%, > 50%), and the chemotherapeutic agents received, and were subjected to multivariate and regression analysis. End point was survival in months or to December 1993 (median follow up 24 months). RESULTS: Patients with calcification (n = 31) (28%) were compared to those who did not have calcifications (n = 81). The groups were comparable with respect to sex, age, time to calcification, time to metastases, and treatment type. Calcification occurred independent of the degree of tumour differentiation, the presence of mucinous adenocarcinoma, or the hepatic tumour burden. Nine patients with calcified metastases (30%) had calcification at presentation. Biopsies showed calcification next to viable tumour cells with an absence of an inflammatory reaction. Survival was improved with better primary tumour differentiation and less tumour burden. The presence of calcification had a statistically highly significant improvement in survival (P < 10(-6), relative risk = .19) independent of other variables. CONCLUSIONS: The presence of calcification within a colorectal liver metastasis appears to imply a significantly better prognosis.

Aged↗