Search PubMed⌕ Search

Biomedical subjects

D Moore

Publications and source records attributed to D Moore.

At least 379 records · Page 21Linked to original sources
PubMedDate not supplied

Acrylamide causes preimplantation abnormalities in embryos and induces chromatin-adducts in male germ cells of mice.

Acrylamide, a known male postmeiotic germ cell mutagen, caused a dose-dependent increase in the frequency of morphologic abnormalities in preimplantation embryos. Single-cell eggs, growth retardation, and blastomere lysis were detected after paternal treatment with acrylamide (10 to 50 mg/kg, 5 d). The major effects were seen at weeks 1 to 3 after male treatment, with the highest level of abnormalities at the first week (> 90% vs. 5% in control). The frequency of abnormal four-day embryos was similar to preimplantation loss assessed at 15 to 16 d p.c. A > 100-fold elevation of chromatin adducts in sperm was observed during 1st and 2nd week after treatment, after which adduct levels decreased to baseline level. However, morphologic defects in embryos are not fully explained by the spermatid adduct curve. These findings demonstrate the effects of paternal exposure to acrylamide on preimplantation development and indicate a potential risk to the offspring of men exposed to acrylamide.

Acrylamide↗
PubMedDate not supplied

Self-judged comprehension in adults: effects of age and skill.

We used an error detection paradigm to examine the effects of skill on young (M = 23.74) and old (M = 68.87) adults' self-judged comprehension of texts. Skill was defined as the ability to evaluate comprehension by detecting text problems. Multiple regression results indicated that problematic texts produced lower comprehension judgments for older readers, regardless of level of skill, than for younger readers. Only more skilled younger readers tended to lower their comprehension judgments for problematic text. Younger adults who were less skilled at evaluating their comprehension assessed their comprehension as superior to their more skilled peers. Less skilled older adults appear to know, better than less skilled younger adults, when they do not comprehend a text. Research is needed to examine older adults' perceived self-efficacy and use of regulation strategies to resolve comprehension failures.

Adolescent↗
PubMedDate not supplied

Elaborations in adults' text recall: relations to working memory and text recall.

We examined differences in the elaborative statements produced by younger (mean age = 22.19) and older (mean age = 76.56) adults during text recall as well as relations between elaborative statements and text recall and working memory. Three types of elaborative statements were examined: personal (reactions to a text), inferential (inferences derivable about a text), and metacognitive (statements concerning understanding or memory of a text). Older adults made more personal elaborations during text recall than did younger adults. Younger and older adults did not differ in the amount of inferential or metacognitive elaborations they made, although all adults made more metacognitive comments when texts contained problematic information. Personal elaborations were negatively related to recall and accounted for a substantial portion of the age-related variance in recall. Personal elaborations were also negatively related to processing efficiency, and relations between personal elaborations and working memory and storage capacity were mediated by processing efficiency. The results are consistent with the view that an age-related increase in non-goal-path thoughts, due to inhibitory problems or a different style of text processing, may be related to age-related deficits in text processing.

Adolescent↗
PubMedDate not supplied

The effects of life events on cardiovascular reactivity to behavioral stressors as a function of socioeconomic status, ethnicity, and sex.

OBJECTIVE: The purposes of this study were 1) to examine the effects of stressful life events on cardiovascular reactivity to acute laboratory stressors in youth and 2) to determine whether these effects varied as a function of socioeconomic status, ethnicity, and/or sex. METHODS: Four hundred eighty-three youths (mean age = 16.7 years; 249 Caucasian Americans [126 males, 123 females] and 234 African Americans [109 males, 125 females]) completed the Adolescent Resources Challenge Scale (ARCS), a measure of stressful life events, and underwent two laboratory stressors (a car-driving simulation and the Social Competence Interview) during which blood pressure, heart rate, cardiac output, and total peripheral resistance were assessed. RESULTS: Youths who reported high levels of stressful life events showed smaller increases in blood pressure (both systolic and diastolic) and heart rate to the car-driving simulation but larger increases in cardiac output in response to the Social Competence Interview than did youths who reported low levels of stressful life events. The effect of stressful life events on cardiovascular reactivity was not moderated by sex, ethnicity, or socioeconomic status. Higher family socioeconomic status was associated with greater blood pressure, heart rate, and cardiac output increases in response to the Social Competence Interview. CONCLUSIONS: The attenuating effects of stressful life events on cardiovascular reactivity in response to car-driving simulation in youths are consistent with an inoculation effect, whereas the potentiating impact of stressful life events on reactivity observed during the social stressor interview is compatible with a possible cost of coping effect.

Adaptation, Psychological↗
PubMedDate not supplied

Surgical decompression of chronic central core lesions of the Achilles tendon.

We report the outcome of 14 athletes with chronic recalcitrant achillodynia and central core degeneration of the Achilles tendon. The patients underwent surgery after an average time from onset of symptoms to surgery of 87 months. All patients had undergone conservative management, including physical therapy treatment, orthoses, nonsteroidal antiinflammatory drugs, and steroid injections. At an average follow-up of 35 months (range, 27 to 52), only 5 patients had an excellent or good result, despite reexploration in 6 of the 14 patients. In athletes with long-standing pain and central core degeneration of the Achilles tendon, prognosis is poor, and even reexploration is not successful. If the referral pattern allows, surgery should probably be undertaken earlier.

Achilles Tendon↗
PubMedDate not supplied

Dental erosion: a case study of a marathon runner.

This paper presents a case study of a recreational runner who unwittingly has caused severe damage to her dentition through her lifestyle and dietary habits. It should serve as a reminder to all dental practitioners that dental problems occur even in patients who seem to be following a healthy lifestyle.

Beverages↗
PubMedDate not supplied

Revegetation of an abandoned uranium millsite on the Colorado Plateau, Arizona.

We attempted to restore native plants on disturbed sites at a former uranium mill on the Colorado Plateau near Tuba City, AZ. Four-wing saltbush [Atriplex canescens (Pursh) Nutt.] was successfully established in compacted caliche soil and in unconsolidated dune soil when transplants were irrigated through the first summer with 20 L/plant/wk. The caliche soil was ripped before planting to improve water-holding capacity. The diploid saltbush variety, angustifolia, had higher survival and growth than the common tetraploid variety, occidentalis, especially on dune soil. The angustifolia variety grew to 0.3 to 0.4 m3 per plant over 3 yr even though irrigation was provided only during the establishment year. By contrast, direct seeding of a variety of native forbs, grasses, and shrubs yielded poor results, despite supplemental irrigation throughout the first summer. In this arid environment (precipitation = 100 to 200 mm/yr), the most effective revegetation strategy is to establish keystone native shrubs, such as four-wing saltbush, using transplants and irrigation during the establishment year, rather than attempting to establish a diverse plant community all at once.

Conservation of Natural Resources↗
PubMedDate not supplied

Manipulation of intra- and extracellular pH in spontaneous canine tumours by use of hyperglycaemia.

We evaluated the use of hyperglycaemia to reduce tumour pH in dog with spontaneous tumours. Dogs were randomized to two groups: control and glucose. Intravenous administration of 20% glucose was used to induce and maintain hyperglycaemia. Extra- and intracellular tumour pH were measured using interstitial pH microelectrodes and 31P-MRS, respectively. During the administration of glucose, the mean (+/- SEM) blood glucose concentration was 419.8 (+/- 32.8) and 121.1 (+/- 8.0) mg/dl for the glucose and control groups, respectively. The mean extracellular tumour pH before and following 90 min of hyperglycaemia was 7.15 (+/- 0.08) and 7.15 (+/- 0.09). During consecutive measurements, intracellular tumour pH did not change significantly for the control group or the group subjected to hyperglycaemic manipulation. In contradistinction to previous rodent studies, our results demonstrate that hyperglycaemia alone is not sufficient to manipulate either intra- (pHi) or extracellular (pHe) hydrogen ion concentration in spontaneous canine soft tissue tumours.

Animals↗
PubMedDate not supplied

Transection of the inferior rectus muscle.

Four cases of isolated inferior rectus transection secondary to trauma are presented. The clinical and CT scan findings are illustrated. The CT scan findings are very useful in the surgical management and prognosis of these cases.

Adult↗
PubMedDate not supplied

Experience-expectant plasticity in the mushroom bodies of the honeybee.

Worker honeybees (Apis mellifera) were reared in social isolation in complete darkness to assess the effects of experience on growth of the neuropil of the mushroom bodies (MBs) during adult life. Comparison of the volume of the MBs of 1-day-old and 7-day-old bees showed that a significant increase in volume in the MB neuropil occurred during the first week of life in bees reared under these highly deprived conditions. All regions of the MB neuropil experienced a significant increase in volume with the exception of the basal ring. Measurement of titers of juvenile hormone JH) in a subset of bees indicated that, as in previous studies, these rearing conditions induced in some bees the endocrine state of high JH associated with foraging, but there was no correlation between JH titer and volume of MB neuropil. Treatment of another subset of dark-reared bees with the JH analog, methoprene, also had no effect of the growth of the MB neuropil. These results demonstrate that there is a phase of MB neuropil growth early in the adult life of bees that occurs independent of light or any form of social interaction. Together with previous findings showing that an increase in MB neuropil volume begins around the time that orientation flights occur and then continues throughout the phase of life devoted to foraging, these results suggest that growth of the MB neuropil in adult bees may have both experience-expectant and experience-dependent components.

Animals↗
PubMedDate not supplied

Primary care for children with brain injury.

Children who have sustained a brain injury should receive specialized, coordinated, family-centered care from their primary care providers. By knowing more about the etiology, assessment, associated conditions, and prevention of pediatric TBI, medical providers can better address the multiple needs of the child and family as they cope with new challenges. The management of pediatric brain injury can be complex and time consuming, but we must all be responsive to the needs of these children and their families to ensure their good health, their welfare, and their happiness.

Accident Prevention↗
PubMedDate not supplied

[Ileoanal anastomosis with and without reservoir in children and adolescents with ulcerative rectocolitis and familial polyposis].

We compared the postoperative evolution of patients in whom an ileoanal anastomosis was performed, with (group 1, n:9) an without (group 2, n:7) an ileal reservoir. 3 of the 9 patients in group 1 developed intractable diarrhea, it was necessary to reoperate these children and to construct an ileal reservoir. It was not necessary to reoperate any of the group 2 patients; 2 of whom still have an ileostomy due to the presence of preanastomotic abscess. These 2 last patients where excluded from the following analysis. 2 months after surgery, children in group 1 had 16 +/- 2 bowel movements a day, compared with 8 +/- 2 in group 2, p less than 0.05. Children in group 1 did less well than those in group 2 when the following parameters were compared: fecal incontinence (7/9 vs 0/5), perianal dermatitis (6/9 vs. 1/5), treatment with antidiarrheal agents (5/9 vs 0/5), missing school (4/9 vs 0/5) and diminished social activities (4/9 vs 0/5). We conclude that in children who require colectomy, better results are obtained when an ileoanal anastomosis with ileal reservoir is performed.

Adenomatous Polyposis Coli↗
PubMedDate not supplied

Foreign compound metabolism studies with human liver obtained as surgical waste. Relation to donor characteristics and effects of tissue storage.

An investigation has been conducted on the foreign compound-metabolizing activity of human liver collected fresh from surgery or at autopsy from cadavers 3 to 18 hr old, and the effects of low temperature storage on the foreign compound-metabolizing activity of fresh human liver. The enzyme activities studied were microsomal cytochrome P-450 content, biphenyl 4-hydroxylation, benzo-(a)pyrene metabolism, halothane reduction, and 4-hydroxybiphenyl UDP-glucuronosyl transferase, as well as cytosolic thiopurine methyltransferase, thermostable (TS) phenolsulfotransferase, thermolabile (TL) phenolsulfotransferase, and 5-fluorouracil dehydrogenase. Cadaver liver was a poor source of material for metabolism studies with the majority of the enzymes investigated. There was an 84% decrease in the yield of microsomal protein, a 64% decrease in cytochrome P-450 content per mg of microsomal protein, and a 36% decrease in the biphenyl 4-hydroxylase specific activity in human cadaver liver that was a few hours old. UDP-glucuronosyl transferase showed a 70% decrease, TS phenolsulfotransferase a 84% decrease, TL phenolsulfotransferase a 97% decrease, and thiopurine methyltransferase no significant change in specific activity. The loss of activity for many of these enzymes could be simulated by keeping fresh human liver at the temperature of the body after death. Surgical waste provided a good source of fresh, histologically normal, human liver for metabolism studies. Microsomal cytochrome P-450 content showed a significant increase with the age of the liver donor. Metabolism of benzo(a)pyrene to 3-hydroxybenzo(a)pyrene and benzo(a)pyrene-7,8- and -9,10-diols showed up to 136% higher rates in fresh liver microsomes from female donors.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMedDate not supplied

Too much, too soon?

Explore the source record for details and available documents.

Curriculum↗