PubMed HealthSearch

Biomedical subjects

S Graham

Publications and source records attributed to S Graham.

At least 37 records · Page 2Linked to original sources

Failure to establish congenital bluetongue virus infection by infecting cows in early pregnancy.

Two groups of 10 pregnant cows were inoculated with bluetongue virus type 11 at either 40 or 60 days of gestation. All the cows became infected as judged by the detection of viraemia and seroconversion but they showed no clinical signs. Seventeen of the cows produced live calves none of which showed any evidence of prenatal infection. After challenge with the same virus all the calves became viraemic and seroconverted. The response to challenge of the two groups did not differ from that of a control group challenged at the same time. It was concluded that the infection of pregnant cows in early gestation with this virus did not result in the transplacental infection of the fetuses and did not produce immunotolerant, latently infected calves.

Animals

The pharmacokinetics of total and unbound concentrations of tenoxicam in synovial fluid and plasma.

Tenoxicam is a nonsteroidal antiinflammatory drug with an elimination half-life of 60-80 hours; it is administered once daily. Tenoxicam concentrations were measured in plasma (10 samples) and synovial fluid (6 samples) over a 24-hour dosage interval at steady state in 10 subjects with arthritis who had been taking the drug at a dosage of 20 mg/day for at least 2 weeks. Total tenoxicam concentrations in synovial fluid were always less than those in plasma, and there was little fluctuation in plasma or synovial concentrations over the dosage interval, although there was substantial inter-subject variation in both concentrations. There was a significant relationship between the tenoxicam dosage when expressed as mg/kg of body weight and the average steady-state total concentration of tenoxicam in plasma (r = 0.80, P = 0.006); this accounted for a substantial proportion of the intersubject variation. The mean +/- SD steady-state concentrations in synovial fluid and plasma were 3.9 +/- 1.8 micrograms/ml and 9.2 +/- 3.7 micrograms/ml, respectively, yielding a mean +/- SD synovial fluid: plasma ratio of 0.43 +/- 0.12. Synovial fluid:plasma ratios of total tenoxicam correlated with synovial fluid:plasma ratios of albumin (r = 0.71, P = 0.02). The synovial fluid:plasma ratio of unbound tenoxicam was 0.90 +/- 0.3 (95% confidence interval 0.68-1.11), which was not significantly different from a value of 1 (t = -1.09, P = 0.31).

Adult

Dietary retinol: prevention or promotion of carcinogenesis in humans?

A number of epidemiologic studies have found that 'vitamin A' is associated with a reduced risk for human cancers. Dietary vitamin A indices reflect intake of several compounds in the diet including retinol and pro-vitamin A carotenoids such as beta-carotene, and recent cancer epidemiology studies have attempted to distinguish effects of retinol from those of beta-carotene. While beta-carotene has been associated consistently with a reduced risk for a number of human cancers, particularly epithelial cancers, retinol is generally found to be unassociated with, or positively associated with, risk for many cancers. An apparent enhancement of carcinogenesis has been observed in numerous studies, particularly for cancer of the esophagus, oral cavity, pharynx, larynx, stomach, colon, and rectum. While this finding could be artifactual, experimental studies in animals as well as mechanistic considerations suggest that this effect deserves serious consideration. As discussed in this article, an apparent enhancement of carcinogenesis could be related to an ethanol/retinol interaction, and/or a mechanism involving pro-oxidant activity of retinol but anti-oxidant activity of beta-carotene. This article concludes with suggestions for further research to help clarify the association between retinol and human carcinogenesis.

Diet

Patterns in food use and compliance with NCI dietary guidelines.

We developed multidimensional measures of diet by identifying seven gender-specific patterns among 1,475 male and 780 female subjects selected as neighborhood controls in a case-control study of cancer at various sites. The purpose of this study was to examine these patterns for compliance with the National Cancer Institute (NCI) Dietary Guidelines. Diets were scored and each subject assigned tertile ranks for each pattern. Mean values for indicators of compliance were compared across tertiles for each pattern. No one pattern signified compliance with all guidelines. High-fat patterns in both genders and the low-cost pattern in women were the best indicators of poor compliance with NCI guidelines.

Alcohol Drinking

Associations between breast cancer, plasma triglycerides, and cholesterol.

A case-control study investigating the association between plasma lipids and breast cancer was conducted among women aged 30-80 in Buffalo, NY. All eligible women from a large breast clinic and two area physicians' offices were requested to participate over a one-year period. Subjects completed a health questionnaire and donated a fasting blood sample prior to diagnostic breast biopsies. The 83 women found to have breast cancer (cases) had significantly higher plasma triglyceride values than did the 113 women found not to have breast cancer (controls). Lower plasma beta-carotene values were associated with breast cancer, but only in those women with elevated triglyceride or cholesterol. Plasma cholesterol values were lower in those breast cancer cases presenting with more advanced stages of cancer, suggesting that metabolic effects of clinical and preclinical breast cancer may lower cholesterol levels. Although the limitations of case-control studies are well-recognized, these data suggest an etiologic role for plasma triglycerides and beta-carotene or for related dietary factors.

Adult

High-risk health behaviors associated with various dietary patterns.

We have previously identified dietary patterns among 1,475 male and 780 female normal healthy control subjects in a case-control study of cancer at various sites. In this paper we examine the presence, among persons exhibiting these dietary patterns, of individual health behaviors that may contribute to risks for cancer. Specifically we examine trimming of separable fat from meats, fats used in cooking and as additions to foods, alcohol consumption, and smoking. Results indicate that men and women differ in possession of these high-risk behaviors. Women are more likely to trim fat from meat, consume less alcohol, and have lower exposures to smoking. Their dietary patterns are more independent of the fats used. Several eating patterns are positively associated with total fat intake but differ in their associations with high-risk behaviors. These data suggest that assessing risk associated with dietary patterns sheds more light on disease relationships than studies of single nutrients.

Aged

Relevance of major stress events as an indicator of disease activity prevalence in inflammatory bowel disease.

The impact of psychological stress in recurrence of inflammatory bowel disease (IBD) is unclear. Why some patients with ulcerative colitis (UC) or Crohn's disease (CD) have unrelenting relapses whereas other IBD patients experience long periods of quiescent disease remains an enigma. The authors examined the risk of exposure to major stress events in clinical episodes of IBD. They followed up on 124 persons in a prospective study that monitored behavioral and biological characteristics for a period of 6 months. Stress-exposed subjects demonstrated increased risk of clinical episodes of disease when compared with unexposed subjects (RR = 2.6, 95% CI: 1.3-4.9). Elevated effect measures were highest for the domain of health-related stress (RR = 3.8, 95% CI: 1.5-9.9). In the multiple regression analysis, major stress events remained the most significant indicator of disease activity in the presence of the covariables considered. Only 7% of the variation in disease activity was uniquely attributed to stress. Baseline activity was the other notable indicator of subsequent disease activity in the study sample. All variables considered together explained 52% of the variance observed and implicated factors of potential clinical importance in monitoring recurrence of the disease.

Adult

Folate intake and carcinogenesis of the colon and rectum.

Experimental evidence suggests that folate depletion plays a role in carcinogenesis. A case-control study examining folate intake was conducted. Some 428 colon and 372 rectal cancer cases with matched neighbourhood controls were interviewed regarding usual intake of foods, including food preparation. Unadjusted folate was not associated with risk of either cancer. Controlling for kilocalories, odds ratios (ORs) for those with the highest folate intake were 0.5 (95% confidence interval (CI): 0.24-1.03) and 0.31 (95% CI: 0.16-0.59) for females and males for rectal cancer. There was no change in colon cancer risk associated with folate intake. There was an indication of an interaction of folate and alcohol intake; the difference in risk associated with low and high folate intake was highest for males in the highest alcohol category. Associations were of similar magnitude for other dietary factors correlated with folate. It appears that intake of folate or a correlated factor may be negatively related to risk of rectal cancer.

Alcohol Drinking

Lag time between stress events and risk of recurrent episodes of inflammatory bowel disease.

We followed a cohort of 124 subjects with a history of inflammatory bowel disease to ascertain risk estimates for clinically active disease associated with exposure to recent stress events. We calculated risk estimates for three lag models (-1, 0, + 1 month). The data indicated a strong association between stress exposures and new clinical episodes of disease (RR = 2.9, 95% Cl: 2.0-4.1), most apparent in the immediate period (lag = 0). Risk estimates were also elevated for extended episodes of disease in subjects under stress compared with unexposed subjects. These results underscore the importance of monitoring stress exposures in prevention and treatment of recurrent disease.

Acute Disease

Familial aggregation of bladder cancer stratified by smoking status.

To assess bladder cancer incidence in first-degree relatives of affected probands, bladder cancer patients and matched control probands provided general demographic and smoking information on their first-degree relatives. Bladder cancer incidence was established through information from the New York State Tumor Registry. The risk ratio for relatives of case probands versus relatives of control probands was 1.9; for relatives who smoked, the risk ratio was 2.1, while for nonsmoking relatives, the risk ratio was 1.8. Results from a proportional hazards regression analysis agreed with those above. These results indicate a familial component that is independent of smoking.

Adolescent

Human cytotoxic T cell responses to vaccinia virus vaccination.

Recombinant vaccinia viruses have been proposed as live virus vectors in man to generate both specific humoral and cellular immune responses. The generation of such responses following revaccination was followed in five normal volunteers. All five showed elevated (35- to 6500-fold) vaccinia virus-specific IgG by 14 days post-vaccination, following uncomplicated vaccination by dermal scarification. Four of the five had elevated total serum immunoglobulins with increased spontaneous and pokeweed mitogen-induced immunoglobulin production. Major histocompatibility complex class I-restricted vaccinia virus-specific cytotoxic T lymphocytes (CTLs) were not detected either directly, from peripheral blood mononuclear cells, or following secondary in vitro stimulation, even by limiting dilution analysis. These studies would suggest that vaccination with recombinant vaccinia viruses may provide an insufficient stimulus to the generation of CTLs in vivo.

Adult

Risks associated with source of fiber and fiber components in cancer of the colon and rectum.

In this case-control study, we examined the food sources of fiber and fiber solubility to determine whether particular components of dietary fiber were differentially associated with risk of colon and rectal cancer. In Western New York, cases with pathologically confirmed, single, primary cancers of the colon and rectum as well as age-, sex- and neighborhood-matched controls were interviewed from 1975-1986. The sample included 428 colon case-control pairs (223 females, 205 males) and 422 rectal case-control pairs (145 females, 277 males). Subjects were interviewed regarding usual quantity and frequency of consumption of foods. For the colon, risk decreased with intake of grain fiber for both females and males and with intake of fruit/vegetable fiber for males only. Insoluble grain fiber was more strongly associated with risk than soluble grain fiber. For the rectum, fruit/vegetable fiber was associated with decreased risk, whereas grain fiber was not. There was no difference in risk for soluble and insoluble fiber components for the rectum. Analysis of risk associated with fiber by food source and by components of the fiber may provide insight into possible mechanisms of a fiber effect on cancer of the colon and rectum.

Colonic Neoplasms

Effect of autolymphocyte therapy on survival and quality of life in patients with metastatic renal-cell carcinoma.

To assess the value of autolymphocyte therapy (ALT) in the treatment of metastatic renal-cell carcinoma, 90 patients were randomised to receive every month for six months oral cimetidine plus an infusion of autologous peripheral blood lymphocytes activated in vitro by a previously generated autologous lymphokine mixture, or cimetidine alone. The median follow-up was 15 months. Survival time for the autolymphocyte group was approximately 2.5 times that for the cimetidine group (p = 0.008). Patients who had greater than 500 pg interleukin-1 (IL-1) per ml autologous lymphokine mixture had a six-fold survival advantage over those with less than 500 pg/ml (p less than 0.00005). Men treated with ALT had a four-fold survival advantage (p = 0.001) over men who received cimetidine only. Infusion of the cultured autolymphocytes was accompanied by mild, self-limited fever in 11 of the 45 ALT patients, and by only one instance in which fever was accompanied by tachypnoea and hypotension.

Actuarial Analysis

Cellular requirements for lymphokine secretion by rainbow trout Salmo gairdneri leucocytes.

The ability of different populations of rainbow trout blood leucocytes to produce MAF following stimulation with Con A/PMA was assessed by the amount of NBT reduction in target macrophages. The effect of varying lymphocyte or macrophage number on MAF production in the presence of a constant number of macrophages or lymphocytes respectively, showed that in both cases MAF activity initially increased with increasing cell number and then plateaued. Macrophages alone did not produce MAF whereas some MAF activity was produced by macrophage-depleted lymphocytes, although significantly lower than in the presence of macrophages. Separation of leucocytes into sIg- and sIg+ cells by panning showed that only sIg- lymphocytes could produce MAF and that macrophages were necessary as accessory cells. These results support the contention that fish lymphocytes can be divided into sIg- T cells and sIg+ B cells.

Animals

Isolations of African horse sickness virus from vector insects made during the 1988 epizootic in Spain.

This paper describes the first isolations of African horse sickness virus (AHSV) from insects in Spain. Seven isolations of AHSV serotype 4 were made; four from Culicoides imicola a known vector of the virus elsewhere, two from mixed pools of Culicoides species not including C. imicola and one from blood engorged mosquitoes. Three further isolations of AHSV serotype 4 were also made from horses kept adjacent to the insect collecting sites. This work presents the first definitive identification of the vectors of AHSV in Spain during the 1987, 88 and 89 epizootics. Suggestions are also made concerning the significance of these findings with regard to the epidemiology of African horse sickness in Spain.

African Horse Sickness

Diet in the epidemiology of gastric cancer.

We examined the nutritional epidemiology of gastric cancer in 293 cases and neighborhood-, age-, and sex-matched controls in communities throughout the counties of Niagara, Monroe, and Erie in western New York. The interview was highly detailed, requiring two and one-half hours to complete; it attempted to provide an estimate of total calories ingested as well as of macro- and micronutrients and behaviors that could affect alimentary exposures, such as the use of refrigeration. We found that risk was enhanced by sodium, fat, and retinol. Substantial reductions in risk were associated with ingestion of carotene, especially raw vegetables (including celery, cucumbers, carrots, green peppers, tomatoes, and onions), as well as with increased use of low-temperature food storage. Both refrigeration and carotene could inhibit oxidation products that could act as carcinogens in the stomach.

Adult