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D Morrell

Publications and source records attributed to D Morrell.

At least 19 recordsLinked to original sources
PubMed1999

The effect of the quality of Papanicolaou smears on the detection of cytologic abnormalities.

BACKGROUND: Controversy continues regarding the relation between the quality of Papanicolaou (Pap) smears, especially the presence of endocervical cells (ECC), with the finding of cytologic abnormalities. METHODS: As part of a study regarding performance feedback on the quality of Pap smears, data from 56,475 Pap smears obtained by 176 participating clinicians over a 20-month period were analyzed to assess the relation between the presence of ECC, the categorization of global specimen adequacy as "satisfactory" or "satisfactory with limitations," and the prevalence of atypia and squamous intraepithelial lesions (SILs). RESULTS: Atypia was less likely to be found in "satisfactory" Pap smears than in "satisfactory with limitations" quality Pap smears (odds ratio [OR], 0.6; 95% confidence interval [CI], 0.5-0.6; P < 0.001), even though the latter could contain ECC. No association was found between satisfactory Pap smears and cytologic abnormalities. Compared with specimens with no ECC, an ECC count of > or = 50 on a slide was associated positively with the detection of atypia (OR, 2.1; 95% CI, 1.8-2.4; P < 0.001) or SILs (OR, 1.7; 95% CI, 1.3-2.2; P < 0.001). A similar relation existed between ECC counts of 25-50 (OR, 1.9; 95% CI, 1.1-2.2; P = 0.01) and the detection of SILs. No relation was found between specimens with < 25 ECC and the presence of atypia or abnormalities. CONCLUSIONS: The global adequacy criterion of "satisfactory" assigned to a Pap smear does not indicate that there is a greater likelihood of detecting cytologic abnormalities compared with lower quality Pap smears. To the authors' knowledge, previous studies regarding the link between ECC in the Pap smear and cytologic abnormalities have not addressed the relevance of how many ECC are needed to maximize the identification of abnormalities. The data from the current study support the value of obtaining at least 25 ECC as a quality indicator of sampling.

Adult↗
PubMed1996

Regulation of rat Schwann cell Po expression and DNA synthesis by insulin-like growth factors in vitro.

Myelination by Schwann cells is likely to be regulated in vivo by positive and negative epigenetic factors. In vitro, the positive regulation of myelin differentiation, in particular expression of the major myelin protein Po, can be mimicked by cAMP elevating agents, while serum, transforming growth factor (TGF) beta s, and fibroblast growth factor (FGF)2 have been shown to exert a negative effect on this differentiation. Growth factors which promote Po induction have not, however, been identified previously. Using a forskolin concentration (0.4 microM) which alone produces little Po mRNA or protein induction, we show that insulin-like growth factor (IGF)-I, IGF-II and high concentrations of insulin promote high levels of Po induction, although in the absence of forskolin they have no effect. Another event related to Schwann cell differentiation, induction of galactocerebroside expression in response to cAMP analogues, is also potentiated by IGFs. In a different context, IGFs regulate Schwann cell DNA synthesis. We find that in defined medium forskolin plus FGF2, TGF beta or platelet-derived growth factor (PDGF) BB causes minimal DNA synthesis in the absence of IGFs and that IGFs act as potent mitogens under these conditions. IGFs also potentiate DNA synthesis induced by beta isoforms of neu-differentiation factors (NDFs), although in this case considerable DNA synthesis occurs even in the absence of IGF. These results show that IGFs can act as powerful stimulators of both proliferation and differentiation in Schwann cells, and that the total growth factor input determines which of these pathways IGFs will promote.

Animals↗
PubMed1996

The quality of cervical cancer screening: a primary care perspective.

The bulk of cervical cancer screening is performed by primary care providers; mostly nurses and physicians. The literature regarding the quality of this screening is largely described from three perspectives; clinical, laboratory, and public health. This article describes the primary care perspective regarding issues of quality in cervical cancer screening and suggests areas for improvement. The authors discuss how effectiveness of the test, sampling methods, interpretation by the laboratory, and reporting results impact on the quality of cervical cancer screening. Other factors which influence the quality of screening such as access to care, recall intervals, communication with the patient, costs of testing, and organizational issues are also reviewed.

Communication↗
PubMed1995

Obesity in heterozygous carriers of the gene for the Bardet-Biedl syndrome.

Obesity and renal failure are common manifestations in the autosomal recessive Bardet-Biedl (BB) syndrome. Because obesity and hypertension have been reported frequently in non-homozygous relatives of BB patients, we hypothesized that BB heterozygotes are predisposed to these conditions. Clinical information was collected from 34 patients of BB homozygotes, who are obligate heterozygotes. The proportion of severely overweight fathers (26.7%) was significantly higher than that in comparably aged United States white males (8.9%). We conclude that the BB gene may predispose male heterozygous carriers to obesity. If BB heterozygotes are 1% of the general population, we estimate that approximately 2.9% of all severely overweight white males carry a single BB gene. The BB parents of both sexes were also significantly taller than U.S. white men and women of comparable age.

Adult↗
PubMed1995

General practitioners' background knowledge of their patients.

The aim of the study was to describe the background knowledge of their patients used by general practitioners in decision making in the consultation. Tape-recorded interviews with 22 general practitioners randomly selected from one FHSA, concerning 198 consultations, were used. General practitioners were asked to describe their background knowledge of the first ten patients seen that day, and to describe how their management decisions were influenced by this information. The interviews were analysed from transcripts. All except one doctor appeared to identify patients as 'copers' or 'non-copers'. Decisions which appeared to be linked with coping were: (1) expecting them to have a physical illness; (2) offering reassurance, expecting that to be effective; (3) deciding that there was no need to take action; (4) allowing the patient to decide on some aspect of management. Decisions linked with not coping were: (1) to look for a psychological diagnosis; (2) to offer reassurance, but expecting that not to be effective; (3) to examine or refer because of the doctor's perception of the patient's expectations. General practitioners also appeared to make decisions based on their perception of their patients' social support. If there was thought to be adequate support, or no social stress, the doctors decided (1) to look for a physical diagnosis; (2) to leave some decisions to the patient; (3) not to involve outside agencies in management; and (4) to ignore those areas of the patient's life which were thought not to be a problem. If doctors believed that there were problems with support, they seemed to try to give more of their time, and to refer or investigate more.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Psychological↗
PubMed1995

Urinary insulin-like-growth factor I in normal children: relationship to age, pubertal status and urinary growth hormone.

Authentic insulin-like growth factor 1 (IGF-I) can be detected in human urine at one thousandth of the serum level, with which it correlates closely. The aim of this study was to establish the normal range of urinary IGF-I (uIGF-I) in relation to age, sex, and pubertal status, and to define the relationship between uIGF-I and urinary growth hormone (uGH). IGF-I was measured by RIA after acid extraction of IGF-I binding protein, and separation by gel chromatography in 302 healthy children (149 boys and 153 girls) in whom uGH had already been measured. The mean amount of uIGF-I excreted each night ranged from 17.5 ng (males) and 14.9 ng (females) at pubertal stage I (PS 1), to a peak of 66.8 ng (males) at PS 4, and 55.8 ng (females) at PS 3, coinciding with peak uGH excretion. Highly significant correlations were found between uGH and uIGF-I both before and during puberty (P < 0.01). These findings extend the range of non-invasive investigation available in growth disorders and physiological studies.

Adolescent↗
PubMed1994

Arranging hospital admission for acutely ill patients: problems encountered by general practitioners.

BACKGROUND: Reports in the national press suggest that general practitioners in London are experiencing difficulties in securing hospital admission for their acutely ill patients. AIM: A study was undertaken to investigate the problems encountered by general practitioners in one family health services authority in south east London in arranging acute admissions to hospital. METHOD: A self-report questionnaire was completed by a sample of general practitioners every time an acute hospital admission was attempted. RESULTS: A total of 493 questionnaires were completed by 111 general practitioners over the 47-day study period. Problems during the hospital admission procedure were experienced in 171 (35%) of the cases reported, with 115 of the 537 telephone calls to a hospital (21%) resulting in a refusal to admit the patient to that particular hospital. The main problem reported was that of 'no beds available', an obstacle to admission that was more likely to be encountered if the patient was aged 75 years or over than if the patient was younger. CONCLUSION: In the light of the problems reported, possible changes to the current method of arranging acute admissions to hospital in London are discussed.

Adolescent↗
PubMed1994

Cervical smears.

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Family Practice↗
PubMed1993

Tomlinson report.

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Family Practice↗
PubMed1991

Incidence of cancer in 161 families affected by ataxia-telangiectasia.

BACKGROUND: Ataxia-telangiectasia is an autosomal recessive syndrome in which cancers develop in affected homozygotes at a rate approximately 100 times higher than in unaffected age-matched subjects. Retrospective studies have shown that persons heterozygous for the ataxia-telangiectasia gene, who make up about 1 percent of the general population, also have an excess risk of cancer, particularly breast cancer in women. Patients with ataxia-telangiectasia and cells derived from homozygotes and heterozygotes are unusually sensitive to ionizing radiation. METHODS: Cancer incidence and mortality, mortality from ischemic heart disease, and mortality from all causes were compared prospectively for a mean of 6.4 years in 1599 adult blood relatives of patients with ataxia-telangiectasia and 821 of their spouses, who served as controls, in 161 families affected by ataxia-telangiectasia. In a case-control substudy, we compared documented occupational and fluoroscopic diagnostic exposures to radiation in the 19 female blood relatives in whom breast cancer was first diagnosed during the period of prospective observation with the exposures in 57 matched blood relatives who did not have breast cancer. RESULTS: Cancer rates were significantly higher in the group of blood relatives than in their spouses, specifically in the subgroup of 294 blood relatives who were known to be heterozygous for the ataxia-telangiectasia gene. The estimated risk of cancer of all types among heterozygotes as compared with noncarriers was 3.8 in men and 3.5 in women, and that for breast cancer in women was 5.1. Among the blood relatives, women with breast cancer were more likely to have been exposed to selected sources of ionizing radiation than controls without cancer (odds ratio = 5.8, P = 0.005). Male and female blood relatives also had 3-fold and 2.6-fold excess mortality from all causes, respectively, from the ages of 20 through 59 years. CONCLUSIONS: The ataxia-telangiectasia gene predisposes heterozygotes to cancer, particularly breast cancer in women. There is also excess mortality from all causes in adults under the age of 60. Diagnostic or occupational exposure to ionizing radiation probably increases the risk of breast cancer in women heterozygous for ataxia-telangiectasia.

Adult↗
PubMed1990

Cancers in 44 families with ataxia-telangiectasia.

Cancer incidence was measured retrospectively in 574 close blood relatives of white ataxia-telangiectasia (A-T) patients and 213 spouse controls in 44 previously unreported families. The cancer incidence rate in the adult blood relatives was significantly elevated over the rate in the spouse controls (rate ratio = 3.9, p less than 0.01). For heterozygous carriers of the A-T gene, the relative risk of cancer was estimated to be 6.1 (p less than 0.005) as compared with nonheterozygotes. The most frequent cancer site in the blood relatives was the female breast, with nine cancers observed. These findings provide further support for the hypothesis that heterozygotes for the A-T gene are predisposed to cancer.

Adult↗
PubMed1990

Cancer predisposition of ataxia-telangiectasia heterozygotes.

Ataxia-telangiectasia (A-T) is a progressive neurologic disorder in which there is varied immune dysfunction, an excess sensitivity to ionizing radiation, and a striking predisposition to cancer. It is the autosomal recessive syndrome for which there is the strongest evidence, derived from retrospective studies of cancer incidence and mortality in A-T families, that the heterozygote is predisposed to cancer. We present, in tabular form, the specific cancer sites or types most likely to be associated with A-T heterozygosity. These include solid tumors of the breast, pancreas, stomach, bladder, and ovary, and chronic lymphocytic leukemia. We also introduce a new method to test these associations. As soon as molecular probes for the A-T allele(s) are available, this new research design will be used to test rigorously each association, hypothesized on the basis of previous data, between a specific cancer site and A-T heterozygosity.

Ataxia Telangiectasia↗
PubMed1988

Circulatory disease mortality and diabetes incidence in 27 families with Friedreich ataxia.

Friedreich ataxia (FRA) is an autosomal recessive neuromuscular disorder in which nearly all affected homozygotes eventually develop significant cardiomyopathy and a substantial proportion also develop diabetes mellitus. Diabetes and early heart disease have been observed previously in close blood relatives of FRA patients. To test the hypothesis that FRA heterozygotes may have elevated rates of heart disease mortality and diabetes incidence, we compared the rates of these conditions in 1,191 adult blood relatives to those in 745 nonblood relative spouse controls in 27 families of FRA patients. We found no evidence for an excess of diabetes in the blood relatives. For three broad categories of circulatory disease mortality, the FRA blood relatives had significantly higher rates than the spouse controls. However, when each relative's prior probability of heterozygosity for the FRA gene was taken into account, the resulting estimates of relative risk of dying from circulatory disease for FRA heterozygotes compared to nonheterozygotes were not significantly elevated. Since the latter analysis provides the best test of the hypothesis, our data did not strongly support the hypothesis that FRA heterozygotes are at increased risk of cardiac death.

Cardiovascular Diseases↗
PubMed1988

Change from aerobic to anaerobic metabolism after brain death, and reversal following triiodothyronine therapy.

Brain-dead organ donors are depleted of circulating triiodothyronine (T3) and show features suggestive generally of anaerobic metabolism at the tissue level, accompanied by deteriorating hemodynamic function. The principle of single-bolus kinetics with labeled carbon compounds (14C-R), with subsequent measurement of both plasma activity and of exhaled 14C O2 has therefore been used to study glucose, pyruvate, and palmitate utilization under conditions of (1) sedation, (2) brain death, and (3) brain death with T3 therapy in the baboon. Serum lactate and plasma-free fatty acid concentrations were also measured. There was a major change in metabolic oxidative processes following brain death. The rate of glucose, pyruvate, and palmitate utilization was markedly reduced, and there was an accumulation of lactate and free fatty acids in the plasma, indicating a general change from aerobic to anaerobic metabolism. The administration of T3 to the brain-dead baboon resulted in a dramatic increase in the rate of metabolite utilization, and a reduction in the plasma concentrations of plasma lactate and free fatty acids, indicating an apparent reversal from tissue anaerobic to aerobic metabolism. We suggest that T3 should be administered to all brain-dead potential organ donors to correct and maintain a more physiologic metabolic status and thus to improve organ function.

Aerobiosis↗