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A Fulton

Publications and source records attributed to A Fulton.

At least 19 recordsLinked to original sources
PubMed1998

Prospective evaluation of prenatal maternal serum screening for trisomy 18.

OBJECTIVE: Our goal was to evaluate the performance of prenatal serum screening for trisomy 18. STUDY DESIGN: All 40,762 samples for maternal serum testing (August 1991 to June 1994) with a trisomy 18-positive screen (n = 175, alpha-fetoprotein < or =0.75 multiples of the median, unconjugated estriol < or =0.60 multiples of the median, human chorionic gonadotropin < or =0.55 multiples of the median) were analyzed. Results of all amniocenteses, ultrasonographic studies, and birth or death certificate information were obtained from the Iowa Expanded Serum Screening Program, the Iowa Department of Public Health, and the Iowa Birth Defects Registry. RESULTS: We obtained the expected screen-positive rate for trisomy 18 (0.43%, 175/40,762). Fourteen samples from outside the state were excluded, which left 161 cases with outcome data obtained through amniocentesis (n = 121), birth certificates (n = 34), telephone contact (n = 2), or a sonogram indicating a nonviable gestation (n = 4). Of 121 screen-positive women undergoing amniocentesis, 119 had a normal karyotype and 2 had an abnormal karyotype: 69,XXY and 47,XY,+18. Of 36 who declined amniocentesis, none had findings consistent with aneuploidy on clinical neonatal examination. Of the 103 patients who had a detailed ultrasonographic study at the University of Iowa, 27 had a subtle fetal abnormality or growth alteration. Both cases with aneuploidy were in this group. An additional 7 cases of trisomy 18 without the typical trisomy 18 maternal serum screening pattern were diagnosed during this period either at amniocentesis performed because of increased Down syndrome risk indicated by serum screening (n = 1), by elevated alpha-fetoprotein level (n = 1), or by advanced maternal age (n = 2) with serum for screening drawn coincidentally, or they were diagnosed postnatally (n = 3). Three of the 7 cases had early second-trimester ultrasonographic examinations, and all showed abnormalities. CONCLUSIONS: The detection rate of trisomy 18 among patients offered amniocentesis was significantly lower (p < 0.05) than the expected rate (10/161 on the basis of published data). Combining serum screening with detailed ultrasonographic evaluations may improve predictive value by more precisely targeting amniocentesis toward those at highest risk.

Adult↗
PubMed1992

Serum cortisol concentration and testosterone to cortisol ratio in elite prepubescent male gymnasts during training.

Serum cortisol concentrations and testosterone:cortisol concentration ratios of eight prepubescent elite male gymnasts (mean age 10 years 11 months) and 11 controls (mean age 11 years 1 month) were examined during 5 consecutive training days. During this period, the gymnasts trained 3 h each day with moderate intensity mobility, strength and skill exercises while the controls were relatively sedentary. Blood samples were taken from all the boys in both groups before (1630 hours) and 30 min after (2000 hours) training on 4 days. Serum cortisol concentrations of the gymnasts were not significantly different from those of the controls throughout the experiment. Serum cortisol concentrations of both groups were significantly larger (P < 0.05) at 1630 hours than at 2000 hours, indicating that cortisol secretion followed the typical adult circadian change, seemingly unaltered by training. However, there was a significant decrease (P < 0.05) in the testosterone:cortisol ratio of the gymnasts when compared with controls from day 1 to day 3. After a rest on day 4 the testosterone: cortisol ratio of the gymnasts significantly increased (P < 0.05) but the ratio of the control group also increased indicating that there may have been some day-to-day change by factor(s) other than training. The most obvious factor which may have accounted for the unresponsiveness of serum cortisol concentration to the gymnastics training was that the exercise intensity was too low. However, several days of the training seemed to reduce the anabolic to catabolic balance but further experiments are needed to confirm this finding.

Child↗
PubMed1992

Albinism.

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Albinism, Ocular↗
PubMed1991

Young and old faces in young and old heads: the factor of age in face recognition.

Research on aging and face recognition has shown age-related differences that are reflected most clearly in false-alarm errors. Elderly subjects exceed young adults in false recognitions that new faces are "old." To determine if this difference between young and elderly subjects might differ for young versus elderly faces, an experiment was conducted in which half of the young and elderly subjects studied and recognized young and middle-aged faces, and the remainder studied and recognized middle-aged and elderly faces. Replicating prior research, age-related deficits in recognition accuracy (d') were reduced with older faces, and this effect generalized from measures of face recognition to measures of face-picture recognition. However, the age-related increase in false recognitions of faces was not affected by face age.

Adult↗
PubMed1991

False recency and false fame of faces in young adulthood and old age.

Studies of age differences in face recognition have shown age-related increases in false-alarm errors: elderly persons exceed young adults in judging new faces to be old. To distinguish among theoretical accounts of this finding, we compared young and elderly subjects in two recognition tasks: (1) that of judging whether faces were recent or nonrecent, and (2) that of judging whether faces were famous or nonfamous. The major independent variable was prior presentation of faces-including nonrecent and nonfamous foils-1 week before the test. False recent judgments in response to nonrecent faces and false famous judgments in response to nonfamous faces were higher among the elderly. Moreover, these age-related differences in false-alarm rates were larger for faces viewed 1 week previously than for entirely new faces. The findings suggest that, compared to young adults, older individuals rely relatively more on perceived familiarity, and relatively less on recollection of context, in making recognition decisions.

Adult↗
PubMed1991

Familiarity and recognition of faces in old age.

Elderly persons exceed young adults in false recognitions of new faces. One account claims there are age-related deficits in memory for context of encounter with faces. Because of these deficits, elderly persons frequently recognize faces on the basis of perceived familiarity (i.e., resemblance to face representations in memory), which is high for some new faces. To test this context-recollection hypothesis, we had young adult and elderly subjects judge whether faces: (1) had been seen previously in a test (though no face was repeated), and (2) were subjectively familiar (though no face was famous). The elderly exceeded the young subjects in seen-before judgements (false recognitions), and only the elderly showed a positive correlation between false recognitions and subjective familiarity. In Experiment 2, this finding was extended from false recognitions to correct recognitions, supporting the view that elderly persons, compared to young adults, rely more on resemblance in recognizing faces.

Adult↗
PubMed1989

Correlation of natural killer activity with tumorigenesis of a preneoplastic mouse mammary lesion.

Tissue infiltrating lymphocytes isolated from the preneoplastic mouse mammary hyperneoplastic alveolar nodule (HAN) tissue line C4 express high levels of natural killer (NK) activity, which gradually wanes as spontaneous tumors develop (W. Z. Wei and G. Heppner. Br. J. Cancer, 55: 589-594, 1987). Experiments were performed to test whether modulation of NK cell activity would be associated with altered progression of HAN to tumor. Administration of polyinosinic-polycytidylic acid, which activates NK activity but does not directly affect mammary epithelial cell growth, to HAN-bearing mice enhanced tumor progression, as measured by a decrease in the latency period and increase in the incidence of mammary adenocarcinomas developing in the HAN implants. Antiasialo GM1, which reduces NK activity, reduced tumor progression. The net effect of indomethacin, which may inhibit mammary epithelial cell growth but enhances NK cell function, was to prolong the latency period of tumor development. However, this effect was reversed by interleukin 2, which activates NK cells. These findings suggest that NK activity may provide positive signals for progression of preneoplastic mammary lesions to frank neoplasia.

Animals↗
PubMed1989

Aging and memory for pictures of faces.

The hypothesis that pictorial aspects of face-recognition memory are lower in old age was tested in 2 studies. Young and elderly Ss viewed 48 face pictures, and then took a test containing identical copies of input faces, pictorially changed versions of input faces, and entirely new faces. Replicating prior findings, Experiment 1 showed that false recognitions of entirely new faces were higher among elderly Ss. However, there were no age differences in distinguishing identical from pictorially changed faces. Using a modified test, Experiment 2 showed that although the elderly Ss had good knowledge that changed faces were changed, they had relatively poor knowledge of how they were changed. There appears to be age differences in analytical matching of pictorial information against information in memory.

Adult↗
PubMed1989

Effect of salivary proteins on binding curves of three radioimmunoassay kits: Amerlex-M progesterone, Amerlex cortisol, and Biodata testosterone.

Radioimmunoassay (RIA) is generally used to measure certain salivary hormones because of its high sensitivity. For speed and simplicity, it has been used in the form of "direct" assays, i.e., without first extracting the analyte from its matrix. Investigating the effect of the principal salivary proteins on the binding behavior of three commercial RIA kits, we found that the Amerlex-M [125I]progesterone binding was greatly reduced when alpha-amylase and mucins were added to the binding medium, whereas IgA and IgG were less effective. The Serono Biodata [125I]testosterone binding was unaffected by proteins, while the Amerlex [125I]cortisol binding was decreased by alpha-amylase and mucins. The protein influence was largely eliminated when an extraction step was incorporated. Thus, direct RIA of saliva may be subject to matrix effects, to extents that vary with the kit and that may adversely affect the quality of the assay results.

Humans↗
PubMed1987

Intramuscular vitamin E repletion in children with chronic cholestasis.

Progressive spinocerebellar degeneration was identified in six children with chronic cholestatic liver disease and attributed to severe vitamin E deficiency. In addition to areflexia, ataxia, dysmetria, and diminished vibratory and position sense, three patients had pigmentary retinopathy. Abnormalities were present on electromyography, nerve conduction studies, and electroretinography. Because the vitamin E deficiency was not corrected by oral administration of massive doses of vitamin E, vitamin E was administered by the intramuscular route. With doses of 50 to 100 mg of vitamin E every three to seven days, over a 32-month interval (range, 15 to 44 months), vitamin E deficiency and abnormal red blood cell peroxide hemolysis were corrected. Other than discomfort and occasional edema at the site of injection, there were no side effects of parenteral vitamin E therapy. In several other studies intramuscular vitamin E therapy has produced significant neurologic improvement in patients with similar characteristics. In this study clinical progression of spinocerebellar degeneration was arrested but improvement could not be demonstrated despite adequate vitamin E replacement.

Adolescent↗
PubMed1987

Effectiveness of a controlled drinking self-help manual: one-year follow-up results.

Following the description of six-month follow-up results by Heather et al. (1986), this article reports one-year follow-up for a cohort of media-recruited problem drinkers sent either a controlled drinking self-help manual or a general advice and information booklet. Among those remaining in the sample, mean reduction in drinking at six months had been retained at the one-year point. This stability of reduced consumption included respondents showing evidence of late dependence or high consumption at initial assessment. When respondents who had received other forms of treatment had been excluded, the results confirmed the superior effectiveness of the self-help manual in enabling problem drinkers to reduce consumption. Evidence for a superior outcome among respondents interviewed by telephone, rather than contacted solely by post, was again observed. Some limited evidence is presented as to the reliability and validity of self-reports of consumption in the main sample.

Alcohol Drinking↗
PubMed1986

The role of filtration in the provision of leukocyte poor red cells to multitransfused patients.

Five techniques for the preparation of leukocyte poor red cells were investigated to compare their efficiency in preventing febrile transfusion reactions with their cost of production, in order to establish a cost-effective transfusion programme for chronically anemic patients. Leukocyte depletion and preparation costs per unit for the products were:--microaggregate filtered red cells (MF): 25% leucocyte removal at a cost of $A2; buffy coat poor red cells (BCP): 70% at $A2; washed buffy coat poor red cells (WBCP): 88% at $A28; cotton wool filtered red cells (CWF): 93% at $A23; reconstituted frozen red cells (FC): 97% at $A80. The 5 products were transfused into 103 thalassemia patients with a documented history of febrile transfusion reactions. Reaction rates, expressed as a percentage of units transfused over a 12 mth period (MF 7%, BCP 0.3%, WBCP 0.1%, CWF 0.1%, FC 0.2%) correlated well with the degree of leukocyte depletion. The cost of CWF was reduced by a further 10% using the filter in line during the transfusion. Serum from these patients was screened for leukocyte and platelet antibodies using microlymphocytotoxic, granulocyte immunofluorescence and platelet immunofluorescence assays. There was no correlation between the antibodies present and the type of leukocyte poor product required by a patient to prevent a febrile reaction. A progressive regimen of transfusion (BCP to CWF to FC as the patient reacts) has now been adopted, with considerable cost saving.

Blood Platelets↗
PubMed1985

Differential sensitivity of metastatic versus nonmetastatic mammary tumor cells to macrophage-mediated cytostasis.

Sensitivity to macrophage-mediated cytostasis was determined with 4 tumor cell lines derived from a single, spontaneously arising mouse mammary tumor. Cytostasis was measured in a 48-hour [3H]thymidine-incorporation assay with the use of maleic vinyl ether (pyran) fraction 2 (MVE-2)-elicited peritoneal macrophages as effector cells. Metastatic tumor lines 66 and 410.4 were less sensitive than nonmetastatic lines 67 and 168. Pretreatment of tumor cells with indomethacin for 24 hours before assay increased the cytostatic sensitivity of the metastatic tumor lines but did not affect that of the nonmetastatic tumor lines. Addition of 100 ng lipopolysaccharide (LPS)/ml to the assay mixture of MVE-2-primed macrophages and tumor cells or pretreatment of macrophages with LPS markedly lessened the differences in cytostatic sensitivity among the metastatic and nonmetastatic lines. Pretreatment of tumor cells with indomethacin plus addition of LPS during the effector phase of the assay completely abrogated differences in sensitivity. These results suggest that differences in sensitivity of metastatic versus nonmetastatic tumor cells to macrophage cytostasis are due to both tumor cell (prostaglandin) and effector cell (activation state) factors.

Animals↗
PubMed1984

Relationship of natural killer cytotoxicity to clinical and biochemical parameters of primary human breast cancer.

We have determined the natural killer (NK) activity of peripheral blood lymphocytes obtained from 121 women undergoing surgery for primary breast cancer. NK activity was measured using 51Cr-labeled K562 target cells and effector: target ratios of 100:1, 50:1 and 10:1. The patients' lymphocytes gave a wide range of values with a mean (+/- S.E.) cytotoxicity of 22.6% +/- 1.3, and a median of 20.9% at the 50:1 effector:target ratio. These results did not differ significantly from the mean and median NK levels obtained with the peripheral blood lymphocytes of normal blood donors (mean = 23.1% +/- 1.9, median = 18.8%). Mean NK activity determined at the first postsurgical examination (less than or equal to 6 months postoperative) was significantly lower than the mean NK activity at surgery. The most significant decreases were seen in patients undergoing chemotherapy prior to the first follow-up examination. Subsequent tests (greater than 6 mo, less than or equal to 12 mo) show a recovery of NK activity to preoperative levels. A negative correlation was seen between NK level and maximum tumor diameter. NK levels also varied with tumor histiotype. No association was seen between NK levels and either the number of involved lymph nodes, pathologic tumor grade, the presence of estrogen or progesterone receptor, or the age, menopausal status or smoking history of the patients. A positive correlation was seen, however, between NK levels and number of pregnancies and live births.

Adult↗