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Biomedical subjects

R Wilson

Publications and source records attributed to R Wilson.

At least 559 records · Page 31Linked to original sources
PubMed1989

The influence of time of day on the foraging behavior of the honeybee, Apis mellifera.

The honeybee time sense, or Zeitgedächtnis, is highly adaptive, allowing bees to synchronize their foraging behavior with the peak time of daily floral nectar rhythms. Each foraging group within the honeybee colony shows a high degree of fidelity to one species of flower. Across the day, the temporal accuracy of foraging visits to experimental feeding times varies considerably, being nearly exact for morning-trained foraging groups but becoming less so for foraging groups trained later in the day. The evidence gained in this study suggests that the diel change in accuracy exhibited by foraging groups, which persists after the removal of many potential environmental time cues, is an endogenously driven behavior pattern. Furthermore, it appears that individual bees are continuously and accurately aware of the time of day, but are programmed to forage with greater anticipation to late-day food sources. Therefore, two separate processes contributing to the honeybee time sense are implicated. The first varies with time of day and determines the amount of anticipatory activity directed toward the food source. The second process is invariant across the day and is involved with the individual forager's continuous, accurate awareness of time.

Animals↗
PubMed1989

Consistencies and inconsistencies underlying the quantitative assessment of leukemia risk from benzene exposure.

This paper examines recent risk assessments for benzene and observes a number of inconsistencies within the study and consistencies between studies that should effect the quantitative determination of the risk from benzene exposure. Comparisons across studies show that only acute myeloid leukemia (AML) is found to be consistently in excess with significant benzene exposure. The data from the Pliofilm study that forms the basis of most quantitative assessments reveal that all the AML cases came from only one of the three studied plants and that all the benzene exposure data came from the other plants. Hematological data from the 1940s from the plant from which almost all of the industrial hygiene exposure data come do not correlate well with the originally published exposure estimates but do correlate well with an alternative set of exposure estimates that are much greater than those estimates originally published. Temporal relationships within the study are not consistent with those of other studies. The dose-response relationship is strongly nonlinear. Other data suggest that the leukemogenic effect of benzene is nonlinear and may derive from a threshold toxicity.

Benzene↗
PubMed1989

The prognostic value of TSH receptor binding and thyroid stimulating antibodies following antithyroid drug treatment of Graves' disease.

Following a course of medical therapy for Graves' disease approximately 50% of patients relapse. Previous studies have tried to identify these patients by measuring antibodies to the TSH receptor using a range of assay methods. Such studies have produced widely discrepant results. The aim of the present study was to compare the accuracy with which TSH receptor binding antibodies and thyroid-stimulating antibodies could identify cases of relapse and remission. Fifty-six newly diagnosed and previously untreated Graves' disease patients were recruited into the study. At presentation 4 were negative for TSH receptor antibody and 5 negative for TS-ab. The remaining 47 were positive for TSH receptor antibody and TS-ab although correlation of the degree of abnormality between methods was poor (r = 0.13 NS). After 12 months carbimazole treatment 28 patients relapsed during the following year and 19 remained in remission. TSH receptor antibody levels obtained at the end of a 12-month course of treatment correctly identified 93% who relapsed and 95% who remained in remission. TS-ab levels could only correctly identify 68% who relapsed and 53% who remained in remission. These results have shown that the accuracy with which patients likely to relapse can be identified depends on the assay method chosen which may account for some of the discrepancies found in previously published studies.

Adult↗
PubMed1989

The Kendrick Battery: sensitivity to survival effects.

In an effort to establish the sensitivity of the Kendrick Battery (KB) to mortality effects among institutionalized aged, the residualized pre-death KB scores (Digit Copying, Object Learning Subtests), as well as measures of affect (Zung Depression), and organicity (Luria Pathognomic Scale, Orientation Test) were compared in a sample of fifty-three elderly persons (M age = 82.7, SD = 7.76). Forty-two were female, eleven were male. Twenty-two of these individuals had subsequently died during an eighteen-month period following assessment. Six years after testing, thirty-six of these individuals had died. Step-wise discriminant analyses at each occasion yielded functions defined by the KB subtests, measures of organicity and depression, age of institutionalization, sex, and length of institutionalization that differentiated survivors and nonsurvivors. These data suggested that the Kendrick Battery subtests, measures of depression and organicity, in combination with length of institutionalization and age of admittance predict death among the elderly, for the most part, replicating previous research.

Age Factors↗
PubMed1989

The "in vitro" effects of lithium on the immune system.

This study has examined the "in vitro" effects of Lithium Carbonate on the immune system at low (10(-3), 10(-2)mM) and therapeutic (0.5-1.5 mM) concentrations. Lithium, in the presence of a range of mitogens, was found to increase the incorporation of 3H-thymidine into peripheral blood mononuclear (PBM) cells. At concentrations greater than 1 mM IL2 production was also enhanced. Lithium was also found to increase IgG and IgM production--an estimate of B cell function, the effects being greatest at concentrations within the therapeutic range. However at these levels Lithium inhibited cAMP production. Whether Lithium acts individually on these processes or whether one reaction is merely the result of another is unclear at present.

B-Lymphocytes↗
PubMed1989

A low-cost competitive approach to weight reduction in a Native American community.

Native Americans from two Indian communities, Zuni and Pine Hill, New Mexico, participated in a weight loss competition that utilized promotional, educational and motivational techniques to bring about changes in dietary and exercise behaviors. This evaluative study documents the impact of age, sex, tribal affiliation, initial weight, educational level, employment status, dietary attitude and exercise patterns on program completion and goal attainment. Of 271 participants, 122 (45 percent) completed the competition and lost five pounds or more ('finishers/goal weight achievers'); 127 (47 percent) completed the competition but failed to lose five pounds ('finishers/non-goal achievers'); and 22 (8 percent) did not complete the competition ('non-finishers'). Non-finishers had significantly fewer years of formal education and were more likely to be self-employed or unemployed than finishers. Finishers/goal weight achievers had a significantly greater proportion of males, a greater initial weight and an increased compliance with record-keeping compared to finishers/non-goal achievers. The relative success of the Zuni-Pine Hill 'Eat Right' weight loss competition establishes its importance as a public health model for health behavior change in communities with similar population profiles.

Adult↗
PubMed1989

An endoscopic comparison of the gastroduodenal injury seen with salsalate and naproxen.

Forty endoscopically normal healthy subjects were randomized to receive either BID salsalate (3500 mg/day) or BID naproxen (750 mg/day) for 14 days followed by repeat endoscopic examination. Gastroduodenal lesions were found in 55% (11/20) of the subjects taking naproxen, and 10% (2/20) of those taking salsalate (p = 0.002). Twenty-five percent (5/20) of the subjects taking naproxen and none of the subjects taking salsalate were noted to have severe gastric injury (p = 0.003). There was no difference between the 2 groups in subjective gastrointestinal system adverse experiences. Overall, 95% (19/20) of subjects taking salsalate reported at least 1 adverse experience compared with 60% (12/20) of those taking naproxen (p = 0.02). This was due primarily to the higher number of subjects taking salsalate reporting reversible tinnitus or hearing loss. There was no significant treatment difference in adverse experiences reported for any other organ system. The results of our study support previous observations in patients with rheumatoid arthritis that salsalate produces less gastroduodenal mucosal toxicity than the widely used antiinflammatory agent, naproxen.

Alanine Transaminase↗
PubMed1989

Transcranial Doppler arteriography--a technical note.

Transcranial Doppler (TCD) evaluation of the intracranial vessels was performed in sixty-six patients, 51 of whom received conventional angiography either prior to or subsequent to the ultrasonic arteriogram. Of the 14 patients evaluated for arteriovenous malformations (AVMs), TCD indicated the existence of the AVM in 10 cases. Of those 10 cases, 9 correlated with angiography. Twenty-one patients with aneurysms were evaluated with TCD and only 2 were detected. Twenty-three patients suspected of having ischemic disease were evaluated with TCD, which indicated the presence of stenosis in 21 patients. Twenty of those patients received conventional angiography, with 18 demonstrating significant stenosis.

Blood Flow Velocity↗
PubMed1988

Comparison of lorazepam and flurazepam as hypnotic agents in chronic insomniacs.

Hypnotic efficacy and safety of 3 weeks of daily doses of 2 mg lorazepam or 30 mg flurazepam were compared in a double-blind cross-over study in eight chronic insomniacs between the ages of 29 and 60 years. Subjects were monitored in the sleep laboratory twice weekly for a total of 25 nights. Also, subjective estimates of sleep, vigilance tests, and adverse effects were recorded throughout the study. Findings indicated lorazepam performed better than flurazepam in most sleep parameters. With lorazepam there was improvement from baseline in percentage of sleep time (P less than .05); in total wake time after sleep onset (P less than .01) and in last third of night (P less than .05); in percentage of stage 2 (P less than .05) (weeks 1, 2, 3) and in percentage of night in stage 4 (weeks 2 and 3). Only total wake time from baseline improved (P less than .05) with flurazepam (week 2). Objective and subjective sleep parameters did not correlate well for either drug. Neither drug impaired REM sleep or vigilance test performance. Side effects (grogginess, lethargy; flurazepam only) were few and none was unexpected; neither rebound insomnia nor early morning insomnia occurred with either drug. In summary, both lorazepam 2 mg at bedtime and flurazepam 30 mg at bedtime were found to be effective and safe for treating chronic insomnia, as measured by parameters of sleep and daytime functioning. Lorazepam had more favorable effects on sleep than did flurazepam.

Adult↗
PubMed1988

Early prediction of hypothyroidism following 131I treatment for Graves' disease.

The aim of this study was twofold. Firstly to assess the post treatment predictive value of various biochemical and immunological tests for early hypothyroidism after 131I therapy for Graves' disease, and secondly to determine whether or not pretreatment with Carbimazole protects against post treatment hypothyroidism. The early changes observed in serum T3, T4, TSH, thyroid microsomal and thyroglobulin antibody levels were found to be of no predictive value. A sharp rise, around 2 months, in TRAb levels following 131I therapy indicated that hypothyroidism was likely to occur. This rise was thought to reflect a greater degree of thyroid damage. Lower levels of thyroglobulin in patients who had become hypothyroid by 12 months after treatment would support this view. Five weeks Carbimazole pretreatment in this relatively small group of patients did not appear to protect against hypothyroidism.

Antibodies↗
PubMed1988

Delusional disorder: jealous and nonjealous types.

We studied the records of 101 patients with delusional disorder admitted to the Psychiatric Hospital between 1920 and 1980 and divided the sample into those with jealous (43) and those with nonjealous (58) delusions. Patients and relatives were located by telephone and follow-up information was collected. Compared with the nonjealous patients, the jealous ones were more likely to have had a single delusion, and to have experienced a more benign course as indicated by a lower rate of hospitalization and outpatient treatment. The original delusion tended to remain and the illness did not develop into another form of delusional disorder or other psychiatric illness.

Adult↗
PubMed1988

Minocycline-related black thyroid.

Black pigmentation of the thyroid gland has been observed in patients chronically taking minocycline antibiotics. Pigment changes of the skin, blood vessels, and bone have also been reported. Some of these changes may be caused by traumatic or toxic etiologies, therefore persons conducting forensic death investigations need be aware of minocycline-related changes. This article reviews pigment changes of the thyroid gland and discusses the potential forensic import of such findings.

Forensic Medicine↗