Search PubMed⌕ Search

Biomedical subjects

G H Anderson

Publications and source records attributed to G H Anderson.

At least 19 recordsLinked to original sources
PubMed1992

Estimation of possible impact of non-caloric fat and carbohydrate substitutes on macronutrient intake in the human.

This paper addresses the expected impact of use of macronutrient substitutes by individuals without strong motivation to control macronutrient or energy intake when such modified foods serve as replacements of foods normally ingested rather than as "add-ons". A basic premise of the paper is that individuals are likely to replace a substantial part of the energy equivalent of the original substitution. It further assumes that the macronutrient composition of the additional foods consumed will reflect normal food selection behaviours. The paper derives a description of the expected selection behaviour from examination of the within subject variance in energy and macronutrient intake of 29 subjects followed for 365 consecutive days (the Beltsville One Year Dietary Intake Study). Patterns observed in these subjects were validated through examination of associations between macronutrient intake and energy intake in 600 women, each of whom contributed 6 days of dietary data (USDA CSFII-85). As presently proposed the model suggests that the use of non-caloric fat replacements, by subjects without strong motivation to control fat or energy intake, can be expected to result in a net decrease (less than original substitution) in fat intake and net increases in carbohydrate and protein intakes. Conversely, use of carbohydrate replacements in core foods can be expected to result in net increases in fat and protein intakes and a partial decrease in carbohydrate intake. The magnitude of these net changes is seen to be a function of the extent of replacement of energy.

Adult↗
PubMed1992

A comprehensive program for cervical cancer detection and management.

OBJECTIVE: The purpose of this study was to document some of the results of a comprehensive provincial cytology and colposcopy program for the year 1988 and also to review the impact on the incidence and mortality rates for a clinical carcinoma of the cervix. STUDY DESIGN: This study is a retrospective analysis of the cytologic results of all patients examined provincially in 1988 and a review of the clinical records of patients diagnosed with invasive cancer and those who died of disease. RESULTS: In 1988 490,985 women (40% of all women over the age of 15 in the population) were screened, with 9.2% showing abnormal cells. A total of 79% of women screened were less than 50 years old and accounted for 86.3% of all abnormal smears. Women less than 35 years old were more likely than older women to have moderate dyskaryosis or worse. CONCLUSION: Intensive comprehensive cytology and colposcopy programs reduce not only the incidence and mortality of clinical carcinoma of the cervix but also rates of in situ disease and other precursors.

Adult↗
PubMed1992

Human papillomavirus infection of the uterine cervix. Tissue sampling and laboratory methods affect correlations between infection rates and dysplasia.

Two common tissue sampling techniques--colposcopic biopsy and cervical scrape--and two common human papillomavirus (HPV) detection techniques--Southern blot and dot blot (SB and ViraPap [VP])--were compared to determine whether differences in these techniques alter correlations between "oncogenic" HPVs and cervical neoplasia. In 87 women with persistently abnormal Papanicolaou (Pap) smears, concurrent biopsy and scrape specimens contained HPV in 21 (24%) and contained no HPV in 26 (30%); 30 scrape specimens (34.5%) tested positive when the biopsy tested negative and 10 (11.5%) scrape specimens tested negative when the biopsy tested positive (overall concordance, 54%). Concordance for the most prevalent HPVs (16/18) was 59%. In carcinoma in situ, HPV was found in biopsy samples significantly more frequently than in scrape specimens: 17 of 23 (75%) biopsy samples versus 9 of 23 (39%) scrape specimens (P = 0.018). Conversely, in mild or no dysplasia, 0 of 42 biopsy samples tested positive for HPV 16/18 compared with 12 of 42 scrape specimens (29%; P = 0.0001). Of 229 specimens analyzed by SB and VP, 43 (19%) tested positive and 148 (65%) tested negative for HPV by both methods (concordance, 84%). Corroborative results indicated that 29 of 35 (83%) VP-positive SB-negative results were truly positive compared with none of three SB-positive VP-negative results. Both the cervical sampling technique and the method for HPV detection can significantly affect statistical correlations between cervical dysplasia and HPV type.

Biopsy↗
PubMed1992

Secondary hypertension. An overview of its causes and management.

Primarily hypervolaemic, high output forms of hypertension, with features indicating or strongly suggesting fluid overload as the cause of elevated cardiac output, resulting from renal disease with reduced glomerular filtration rate causing sodium retention, renal tubular causes of sodium retention, greatly excessive sodium intake and low renin hypertension, can be treated by reduction of sodium intake and potentiation of its excretion by diuretic therapy, removal of the cause (e.g. aldosteronoma), and calcium antagonists. Excessive vasoconstriction resulting from noradrenaline (norepinephrine) in neurogenic hypertension, phaeochromocytoma, orthostatic hypertension and alpha-adrenergic drug administration; angiotensin excess due to renal ischaemia brought about by aortic coarctation, renal arterial and arteriolar stenosis, intraluminal obstruction, external renal compression, renin-producing tumours, intrinsic kidney diseases and excessive renin substrate; and vascular structural disorders such as atherosclerosis, arteriolitides and fibrosis with or without calcification of major arteries may also induce hypertension. Secondary hypertension of uncertain mechanism may occur in hyperparathyroidism, hyper-or hypothyroidism, or acromegaly. All are best treated by appropriate correction of the endocrine excess or deficiency. It may also occur in pregnancy, where the mechanism may involve prostaglandin-thromboxane imbalance or calcium deficiency; calcium deficiency with some evidence of benefit from calcium supplements; and the recumbent hypertension paradoxically associated with autonomic failure. Excellent responses to specific correction of the underlying cause or pathogenetic mechanism is usual in young individuals but less frequent in older patients.

Cardiac Output, High↗
PubMed1992

Invasive cancer of the cervix in British Columbia: a review of the demography and screening histories of 437 cases seen from 1985-1988.

The charts of 437 patients with newly diagnosed invasive cervical cancer seen in British Columbia during 1985-1988 were reviewed to determine the age at diagnosis, stage of disease, and histology of the lesions. The patient's immigration status and country of birth were also examined. Two hundred forty-two patients (55%) were age 50 or over and 149 (34%) had preclinical stage IB disease. One hundred seventy of these patients (39%) had never had a cytologic examination before presenting with clinical symptoms, and 45 additional patients had not had cytology for 5 or more years before presenting with invasive disease; thus, a total of 215 cases (49%) fell into the category of "no cytology or cytology longer than 5 years ago." All negative smears were reviewed and in 39 patients (15%) having previous cytology, abnormal cells had been missed or undercalled. Native Indian women made up 10% of the cases of invasive carcinoma, a disproportionately large number as they represent only 2% of the British Columbian population. Of the 27 Native Indian patients in this series, 16 (59%) had never had a cytologic examination. Eighty-five (30%) of 276 women born in Canada had never had a cytologic examination, compared with 34 (71%) of 48 immigrants resident in the country for fewer than 10 years. Twenty-four patients were over the age of 60 with a history of negative Papanicolaou smears. We conclude that, if further gains are to be made in the reduction of death rates from invasive cervical carcinoma, new means must be found to encourage women to participate in Papanicolaou smear screening programs. In particular, special efforts must be made to attract specific groups, such as the Native Indian population and older recent immigrants.

British Columbia↗
PubMed1992

Delayed orthostatic intolerance.

In seven patients who presented with lightheadedness, fatigue, "weakness," and sometimes syncope, blood pressure was found not to fall after standing for 3 to 4 minutes but to fall severely, frequently with syncope or presyncopal symptoms, after 13 to 30 minutes when measured every minute with an automatic device. This delayed orthostatic hypotension could be corrected with inflation of a pressure suit to 45 mm Hg. Its mechanism was further investigated with measurements of plasma catecholamines, plasma cortisol and aldosterone responses to corticotropin, and the effects of norepinephrine infusions on blood pressure and venous contractility. There was normal or excessive orthostatic norepinephrine release in all patients, evidence of impaired venous innervation in the legs in some, and various disorders in the other patients. Since therapeutic improvement in the orthostatic hypotension greatly reduced the symptoms, we concluded that orthostatic hypotension occurring after more than 10 minutes of standing is a potentially debilitating and often correctable disorder.

Adrenal Cortex Function Tests↗
PubMed1979

Effects of a portacaval or peritoneovenous shunt on renin in the hepatorenal syndrome.

Ten patients with hepatorenal syndrome were evaluated before and after creation of a side-to-side portacaval shunt or insertion of a peritoneovenous shunt, procedures which produced an increase in plasma volume and cardiac output. In the seven patients who survived surgery, renal function improved significantly, plasma renin activity fell from high to normal levels, and low levels of plasma renin substrate increased. Prior to surgery, blockade of angiotension II by saralasin produced hypotension and an increase in plasma renin activity, whereas after surgery, saralasin had no effect on blood pressure or renin. Our findings suggest that decreased "effective" plasma volume may be important in the stimulation of renin release and possibly in the pathophysiology of renal failure in the hepatorenal syndrome.

Angiotensinogen↗
PubMed1979

Effect of mineral mixture in diet on protein intake regulation in the weanling rat.

Weanling rats fed a choice of two diets varying only in protein concentration (10 and 60% casein) select a lower proportion of dietary energy as protein when the dietary minerals are supplied by a mineral mixture high in Na, K, and Cl but low in P and Cu (Hi Cl) than when the diets contain the Bernhart-Tomarelli (BT) mineral mixture. The addition of Na and/or K as acetate salts to the BT mineral mixture, to levels in the Hi Cl mixture, had no effect on regulation of protein intake. However, the addition of Na and/or K as chloride salts to the BT mineral mixture resulted in the rats selecting a protein concentration equivalent to the Hi Cl fed group. Weight gains and energy consumption were similar for all groups. It was therefore concluded that dietary chloride affects protein feeding behavior.

Acetates↗
PubMed1979

Diabetes, dietary tryptophan, and protein intake regulation in weanling rats.

The effects of streptozotocin-induced diabetes and tryptophan content of the protein fed on protein intake regulation by weanling rats selecting from 10 and 60% casein diets were evaluated. In uncompensated diabetes the ratio of tryptophan to other selected neutral amino acids in plasma and brain tryptophan were reduced, protein intake per unit of body weight was increased, and serotonin, 5-hydroxyindoleacetic acid, and norepinephrine were unaffected. Enrichment of the tryptophan content of the ingested protein caused a decrease in protein, but not energy consumption of both diabetic and nondiabetic rats. The reduction in protein intake correlated inversely with increases in the tryptophan content relative to the neutral amino acids in plasma and with increases in brain tryptophan and serotonin levels in both diabetic and nondiabetic rats. The data suggest that protein-feeding behavior is regulated by a mechanism that includes brain serotonergic activity with insulin, through its influence on circulating amino acids, determining the quantity of protein consumed in relation to body weight.

Animal Population Groups↗