PubMed Health⌕ Search

Biomedical subjects

F Anderson

Publications and source records attributed to F Anderson.

At least 19 recordsLinked to original sources
PubMed1992

Monitoring hemangioblastoma tumor burden using plasma erythropoietin levels.

We report a 39-year-old female patient with a hepatic hemangioblastoma, polycythemia and elevated plasma erythropoietin (Epo) levels. Following orthotopic liver transplantation (OLTx), her plasma Epo levels and hematocrit normalized but began to rise several months later. This rise correlated with the appearance of multiple lung metastases. The tumor was implicated as the source of excess Epo production using Northern analysis of a resected metastatic lung nodule. Based on our results, the measurement of plasma Epo levels in patients with Epo secreting tumors could be of general utility in assessing tumor burden.

Adult↗
PubMed1991

Isolation of avian osteoclasts: improved techniques to preferentially purify viable cells.

Among the many different methods that have been used to obtain and study isolated osteoclasts from a variety of species, the egg-laying hen maintained on a low-calcium diet has proven to be one of the richest sources of relatively large numbers of osteoclasts. However, recent reports and our own observations indicate that only a very small proportion of the osteoclasts harvested by such methods are viable. The difficulty in obtaining large numbers of viable osteoclasts has restricted studies of osteoclast function and regulation, and so new isolation methods were sought. This report describes an osteoclast isolation procedure designed to substantially enrich for large numbers of viable authentic osteoclasts. Size and cell density differences between osteoclasts and contaminating mononuclear cells have been exploited in developing the methods for osteoclast enrichment. Sequential nonenzymatic and enzymatic procedures, followed by cell density separations, have yielded three populations of osteoclasts derived from chick hatchlings maintained on a low-calcium diet. A corresponding decrease in bone-associated osteoclasts during the sequential isolation scheme has been monitored using an osteoclast-directed monoclonal antibody, 121F. The first two populations contain 40% osteoclasts, which are predominantly (greater than 99%) nonviable, but the third population contains 8-fold more viable osteoclasts, effectively increasing the proportion of viable osteoclasts more than 25-fold in comparison with the first two populations. The osteoclast-like nature of the isolated viable population 3 cells was established by demonstrating ruffled border formation, possession of the 121F monoclonal antibody-reactive osteoclast antigen, bone particle resorption activity, and resorption pit formation on cortical bone slices revealed by transmission and scanning electron microscopy.

Animals↗
PubMed1991

Gonadotropin-releasing hormone agonist-induced ovarian hyperstimulation: low-dose side effects in women and monkeys.

OBJECTIVE: To determine whether low (subtherapeutic) doses of gonadotropin-releasing hormone agonists (GnRH-a) can cause ovarian hyperstimulation. DESIGN: The study is in two parts: a preliminary clinical trial of women and a follow-up study in laboratory primates. SETTING: Normal human volunteers were studied in an academic research environment; primates were in a conventional laboratory setting. PATIENTS, PARTICIPANTS: Human volunteers were selected on the basis of apparent normal health. The monkeys were believed to be of normal reproductive status. INTERVENTIONS: Gonadotropin-releasing hormone agonists were administered at subtherapeutic doses. MAIN OUTCOME MEASURES: After observing ovarian hyperstimulation in two of five women receiving low doses of GnRH-a, a study was specifically designed to test the hypothesis that at low (subtherapeutic) doses of GnRH-a the "flare-effect" can be sustained without achieving down regulation. RESULTS: The data in women and monkeys suggest that a highly individualized response to low GnRH-a doses can be manifested as ovarian hyperstimulation. CONCLUSION: Four points of interpretation are offered: (1) that subtherapeutic doses of GnRH-a can cause ovarian hyperstimulation and related sequelae; (2) this may be a unique observation in that, typically, lower doses of medications have a lower incidence of negative side effects; (3) the findings suggest that GnRH-a prescribed in self-administration regimens may be more prone to such problems in noncompliant patients; and (4) the hyperstimulation response of the ovaries to low GnRH-a doses may indicate a new approach to controlled ovulation induction, although wide individualism was found.

Administration, Intranasal↗
PubMed1979

Comparison of pivmecillinam and cephradine in bacteriuria in pregnancy and in acute urinary tract infection.

48 non-pregnant domiciliary patients referred by general practitioners and 50 pregnant women were treated for bacteriuria with either 500 mg cephradine or 400 mg pivmecillinam every 6 h for 7 days. In the pregnant women, cure rates were over 90% after 2 weeks for both compounds, and after 6 weeks were 86% for cephradine and 78% for pivmecillinam. Cure rates in the non-pregnant were 83% for cephradine and 95% for pivmecillinam at 6 weeks. Seven patients (3 given cephradine, 4 given pivmecillinam) stopped treatment due to side-effects. Overall, side-effects (many of which were trivial) were more common in patients treated with cephradine (51%) than in those receiving pivmecillinam (33%). It is concluded that both drugs are highly effective in these two common types of urinary infection.

Adult↗
PubMed1977

The clinical picture and plasma levodopa metabolite profile of parkinsonian nonresponders. Treatment with levodopa and decarboxylase inhibitor.

Three parkinsonian patients who were nonresponders to levodopa treatment did not improve when shifted to levodopa-decarboxylase inhibitor combination but, instead, experienced involuntary movements. Their plasma levodopa and metabolite profiles showed unusually high baseline 3-0-methyldopa concentrations that further increased significantly during the decarboxylase inhibitor regimen. All patients had 3-0-methyldopa to levodopa ratios greater than 1, even two hours after therapy. Patients who are responders to levodopa-decarboxylase inhibitor combination or to levodopa alone had 3-0-methyldopa to levodopa ratios of less than 1. We discuss the role of 3-0-methyldopa as a metabolite and the significance of the 3-0-methyldopa to levodopa ratio as a predictor of patients' response to levodopa.

Adult↗
PubMed1976

Survival of healthy older people.

The purpose of this study was to discover any relationships which might exist between measurable variables recorded when a healthy group of men and women, aged 70 years and over, were examined and their subsequent survival time. It was found that height, body weight, systolic and diastolic blood pressures, haemoglobin, hand grip power, cardiothoracic ratio, and pulse rate are of no predictive value in the estimation of survival time. Survival is not influenced by marital status or occupational class. For both sexes the degree of kyphosis and age are useful predictive criteria in respect of survival time. However, much research work requires to be done to explain why many people die at the time they do.

Age Factors↗