76
|
Sala E, Warren R, Duffy S, Welch A, Luben R, Day N. High risk mammographic parenchymal patterns and diet: a case-control study. Br J Cancer 2000; 83:121-6. [PMID: 10883679 PMCID: PMC2374534 DOI: 10.1054/bjoc.2000.1151] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Mammographic parenchymal patterns are related to breast cancer risk and are also thought to be affected by diet. We designed a case-control study comprising 200 cases with high-risk (P2 and DY) mammographic parenchymal pattern and 200 controls with low-risk (N1 and P1) patterns in order to investigate the effect of food and nutrient intake on mammographic patterns. Mammograms were evaluated according to the Wolfe classification system. Dietary data were obtained from 7-day food diaries. Mean daily intake of nutrients was computed from standard UK food tables. The adjusted odds ratio (OR) of having a high-risk pattern in women in the highest tertile of total protein and carbohydrate intake was twice that of women in the lowest tertile (OR = 2.00; 95% confidence interval (CI) 1.06-3.77; P = 0.04 and OR = 1.93; 95% CI 1.03-3.59; P = 0.04 respectively). There was no excess risk for fat intake. In addition, there was no association between intake of vitamins and mammographic parenchymal patterns. Total meat intake was strongly and positively associated with high-risk patterns among post-menopausal women (OR = 2.50, 95% CI 1.09-5.69, P = 0.03). Our study suggests that certain macronutrients and foods such as protein, carbohydrate and meat intake influence the risk of breast cancer through their effects on breast tissue morphology, whereas fat and vitamins do not affect mammographic density. It seems that parenchymal pattern acts as an informative biomarker of the effect of some macronutrient and foodstuffs intake on breast cancer risk.
Collapse
|
77
|
Day N, Warren R. Mammographic screening and mammographic patterns. Breast Cancer Res 2000; 2:247-51. [PMID: 11250716 PMCID: PMC138783 DOI: 10.1186/bcr64] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2000] [Revised: 05/18/2000] [Accepted: 05/18/2000] [Indexed: 11/10/2022] Open
Abstract
Mammography is an effective screening modality for the early detection of breast cancer. The reduction in breast cancer mortality is greater for women aged over 50 at screening than for women aged under 50. Mammography can also contribute to an understanding of the biology of breast cancer. Screening trials provide good evidence for the dedifferentiation of a cancer as it develops over time, and the age dependency of this dedifferentiation explains much of the age difference in the effectiveness of screening. Mammographic density is an important predictor of future breast cancer risk, and has potential as an early endpoint in breast cancer prevention trials. Mammographic density is also an important determinant of mammographic screening sensitivity.
Collapse
|
78
|
Hakama M, Pukkala E, Söderman B, Day N. Implementation of screening as a public health policy: issues in design and evaluation. J Med Screen 2000; 6:209-16. [PMID: 10693068 DOI: 10.1136/jms.6.4.209] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To propose principles of design and measures of effect for cancer screening as a public health policy. MATERIAL Finnish routine screening programme with mammography. DESIGN Evaluation of mortality from breast cancer by before-after time trends among Finnish women, by geographical (by municipalities) comparisons, and by intention to screen at an individual level with individual controls who were cluster randomised and matched for age. OUTCOME MEASURES Standardised mortality ratios (SMRs) from breast cancer (total), SMRs from breast cancers diagnosed during the screening programme (refined), deaths prevented, prolongation of life for each breast cancer detected, for each death prevented, for each compliant woman, for each screen, and for each invitation. Relative prolongation of life--that is, time gained versus time spent. RESULTS SMRs only at an individual level with deaths from cancers diagnosed during the screening programme and individually selected controls showed 24% protection, whereas the other SMR measures were too crude or biased because of dilution and selection. Prolongation of life varied from 15 years for each death prevented to two days for each woman screened, with approximation for the prolongation relative to time spent of 3 to 1. CONCLUSIONS A public health policy should be introduced gradually. Those not covered immediately by the policy serve as controls and they should be randomly allocated. The most relevant outcome measure is prolongation of life, and for public health purposes it should be given per unit of intervention, such as screen or invitation, and also related to the time spent for the intervention. Such gains are often small in a Western society, which implies that medicine, including research, should focus more on other aspects of life than length.
Collapse
|
79
|
Sala E, Solomon L, Warren R, McCann J, Duffy S, Luben R, Day N. Size, node status and grade of breast tumours: association with mammographic parenchymal patterns. Eur Radiol 2000; 10:157-61. [PMID: 10663736 DOI: 10.1007/s003300050025] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A case-control study was designed to assess the association of mammographic parenchymal patterns with the risk of in-situ and invasive breast cancer. In addition, the relationship between tumour characteristics and mammographic patterns were also investigated. A total of 875 patients with breast cancer were selected and matched with 2601 controls. Mammographic parenchymal patterns of breast tissue were assessed according to Wolfe's classification, and statistical analysis was by conditional logistic regression. Relative to the N1 pattern, the odds ratios of having an invasive breast cancer associated with the P2 and DY patterns were 1.8 and 1. 4, respectively. In addition, the odd ratios of having an invasive grade 3 breast cancer associated with the P2 and DY patterns were 2. 8 and 3.9, respectively. Relative to the combined N1/P1 pattern, the odd ratios of having a breast cancer smaller than 14 mm, 15-29 mm, or larger than 30 mm associated with the combined high-risk P2/DY pattern (P2 + DY) were 1.2, 1.6, and 2.0, respectively. Finally, women with the P2/DY pattern were twice as likely to have a breast cancer which had already spread to the axillary nodes, compared to women with women with the N1/P1 pattern (odds ratios of 2.1 and 1.4, respectively). Our results confirm previous findings suggesting that mammographic parenchymal patterns may serve as indicators of risk for breast cancer. Our results also suggest that mammographic parenchymal patterns are associated with the stage at which breast cancer is detected.
Collapse
|
80
|
Kelly SJ, Day N, Streissguth AP. Effects of prenatal alcohol exposure on social behavior in humans and other species. Neurotoxicol Teratol 2000; 22:143-9. [PMID: 10758343 PMCID: PMC2699590 DOI: 10.1016/s0892-0362(99)00073-2] [Citation(s) in RCA: 173] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Alcohol exposure during development causes central nervous system alterations in both humans and animals. Although the most common behavioral manifestation of these alterations is a reduction in cognitive abilities, it is becoming increasingly apparent that deficits in social behavior may be very prevalent sequelae of developmental alcohol exposure. In infancy and early childhood, deficits in attachment behavior and state regulation are seen in both alcohol-exposed people and animals, suggesting that these changes are largely the result of the alcohol exposure rather than maternal behavior. In the periadolescent period, people exposed to alcohol during development show a variety of difficulties in the social domain as measured by checklists filled out by either a parent or teacher. Rats exposed to alcohol during development show changes in play and parenting behaviors. In adulthood, prenatal alcohol exposure is related to high rates of trouble with the law, inappropriate sexual behavior, depression, suicide, and failure to care for children. These high rates all suggest that there may be fundamental problems in the social domain. In other animals, perinatal alcohol exposure alters aggression, active social interactions, social communication and recognition, maternal behavior, and sexual behavior in adults. In conclusion, research suggests that people exposed to alcohol during development may exhibit striking changes in social behavior; the animal research suggests that these changes may be largely the result of the alcohol insult and not the environment.
Collapse
|
81
|
Sanci LA, Coffey CM, Veit FC, Carr-Gregg M, Patton GC, Bowes G, Day N. Effects of an educational intervention for general practitioners in adolescent health care principles: a randomized controlled study. West J Med 2000; 172:157-63. [PMID: 18751244 PMCID: PMC1070792 DOI: 10.1136/ewjm.172.3.157] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Objective To evaluate the effectiveness of an educational intervention in adolescent health designed for general practitioners, in accordance with evidence-based practice in continuing medical education. Design Randomized, controlled trial with baseline testing and 7- and 13-month follow-ups. Setting The intervention was delivered in local community settings to general practitioners in metropolitan Melbourne, Australia. Participants A total of 108 self-selected general practitioners. Intervention A multifaceted educational program (2.5 hours per week for 6 weeks) in the principles of adolescent health care, followed 6 weeks later by a 2-hour session of case discussion and debriefing. Outcome measures Objective ratings of videotaped consultations with standardized adolescent patients and self-completion questionnaires were used to measure general practitioners' knowledge, skill, and self-perceived competency; satisfaction with the program; and self-reported change in practice. Results 103 of 108 physicians (95%) completed all phases of the intervention and evaluation protocol. The intervention group showed significantly greater improvements than the control group in all outcomes at the 7-month follow-up (all subjects P<0.03), except for the standardized patients' rating of rapport and satisfaction (P=0.12). 104 participants (96%) found the program appropriate and relevant. At the 13-month follow-up, most improvements were sustained, the standardized patients' rating of confidentiality fell slightly, and the objective assessment of competence further improved. 106 physicians (98%) reported a change in practice attributable to the intervention. Conclusions General practitioners were willing to complete continuing medical education in adolescent health and its evaluation. The design of the intervention, using evidence-based educational strategies, proved effective and expeditious in achieving sustainable and large improvements in knowledge, skill, and self-perceived competency.
Collapse
|
82
|
Day N, Davies C, Enright M, Peacock S, Berendt A, Spratt B. Do bacterial factors determine severe Staphylococcus aureus disease? J Infect 2000. [DOI: 10.1016/s0163-4453(00)80055-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
83
|
Sanci LA, Coffey CM, Veit FC, Carr-Gregg M, Patton GC, Day N, Bowes G. Evaluation of the effectiveness of an educational intervention for general practitioners in adolescent health care: randomised controlled trial. BMJ (CLINICAL RESEARCH ED.) 2000; 320:224-30. [PMID: 10642233 PMCID: PMC27271 DOI: 10.1136/bmj.320.7229.224] [Citation(s) in RCA: 145] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/07/1999] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To evaluate the effectiveness of an educational intervention in adolescent health designed for general practitioners in accordance with evidence based practice in continuing medical education. DESIGN Randomised controlled trial with baseline testing and follow up at seven and 13 months. SETTING Local communities in metropolitan Melbourne, Australia. PARTICIPANTS 108 self selected general practitioners. INTERVENTION A multifaceted educational programme for 2.5 hours a week over six weeks on the principles of adolescent health care followed six weeks later by a two hour session of case discussion and debriefing. OUTCOME MEASURES Objective ratings of consultations with standardised adolescent patients recorded on videotape. Questionnaires completed by the general practitioners were used to measure their knowledge, skill, and self perceived competency, satisfaction with the programme, and self reported change in practice. RESULTS 103 of 108 (95%) doctors completed all phases of the intervention and evaluation protocol. The intervention group showed significantly greater improvements in all outcomes than the control group at the seven month follow up except for the rapport and satisfaction rating by the standardised patients. 104 (96%) participants found the programme appropriate and relevant. At the 13 month follow up most improvements were sustained, the confidentiality rating by the standardised patients decreased slightly, and the objective assessment of competence further improved. 106 (98%) participants reported a change in practice attributable to the intervention. CONCLUSIONS General practitioners were willing to complete continuing medical education in adolescent health care and its evaluation. The design of the intervention using evidence based educational strategies proved an effective and quick way to achieve sustainable and large improvements in knowledge, skill, and self perceived competency.
Collapse
|
84
|
Sala E, Warren R, McCann J, Duffy S, Luben R, Day N. Smoking and high-risk mammographic parenchymal patterns: a case-control study. Breast Cancer Res 2000; 2:59-63. [PMID: 11056684 PMCID: PMC13911 DOI: 10.1186/bcr29] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/1999] [Revised: 10/01/1999] [Accepted: 10/21/1999] [Indexed: 11/18/2022] Open
Abstract
STATEMENT OF FINDINGS: Current smoking was strongly and inversely associated with high-risk patterns, after adjustment for concomitant risk factors. Relative to never smokers, current smokers were significantly less likely to have a high-risk pattern. Similar results were obtained when the analysis was confined to postmenopausal women. Past smoking was not related to the mammographic parenchymal patterns. The overall effect in postmenopausal women lost its significance when adjusted for other risk factors for P2/DY patterns that were found to be significant in the present study, although the results are still strongly suggestive. The present data indicate that adjustment for current smoking status is important when evaluating the relationship between mammographic parenchymal pattern and breast cancer risk. They also indicate that smoking is a prominent potential confounder when analyzing effects of other risk factors such as obesity-related variables. It appears that parenchymal patterns may act as an informative biomarker of the effect of cigarette smoking on breast cancer risk.
Collapse
|
85
|
Sala E, Warren R, McCann J, Duffy S, Luben R, Day N. High-risk mammographic parenchymal patterns and anthropometric measures: a case-control study. Br J Cancer 1999; 81:1257-61. [PMID: 10584891 PMCID: PMC2374338 DOI: 10.1038/sj.bjc.6690838] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Mammographic parenchymal patterns are related to breast cancer risk and are also affected by anthropometric measure. We carried out a case-control study comprising 200 cases with high-risk (P2 and DY) mammographic parenchymal pattern and 200 controls with low-risk (N1 and P1) patterns in order to investigate the effect of body size and shape and breast size on mammographic patterns. Women in the highest quartile of body mass index (BMI) distribution were significantly less likely to have a high-risk pattern (odds ratio (OR) = 0.21, 95% confidence interval (CI) 0.08-0.52, P-value for trend = 0.001) compared to those in the lowest quartile. Relative to women with a waist to hip ratio (WHR) of less than 0.75, the OR of having a high-risk pattern in women with a WHR greater than 0.80 was 0.30 (95% CI 0.14-0.63). Breast size as measured by cup size was significantly and negatively related to high-risk pattern. Our study indicates that both BMI and WHR are negatively associated with high-risk patterns. However, both phenomena are associated with increased risk of breast cancer in postmenopausal women. This negative confounding of two positive risk factors means that the effect of parenchymal patterns on risk will tend to be underestimated when not adjusted for BMI and WHR and vice versa. Thus we may have underestimated the importance of BMI and mammographic parenchymal patterns in the past. Further studies are needed to determine a measure of parenchymal density that is independent of anthropometric measures and breast size.
Collapse
|
86
|
Day N, Musallam K, Wells M. Observed behaviors of patients with probable Alzheimer's disease who are hospitalized for diagnostic tests. J Gerontol Nurs 1999; 25:35-9. [PMID: 10776160 DOI: 10.3928/0098-9134-19991101-10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This study examines observed behaviors of hospitalized patients with probable Alzheimer's disease (AD) undergoing invasive diagnostic procedures. Data was obtained from nursing documentation in the medical records of 30 patients, 10 in each stage of AD (i.e., mild, moderate, severe). In general, analysis of the data revealed that changes in behavior occurred immediately prior to, during, and following these procedures. Specifically, the moderately impaired patients showed the most significant curve over the 5-day observation period, while patients in the mildly impaired group showed a high peak of behavioral change on the test day. The severely impaired group of patients had a higher sustained level of activity throughout the 5-day period. Routine assessment of the patients' usual behaviors, care-givers' knowledge of the stage of disease, and awareness of the potential impact that diagnostics may have on cognitively impaired patients could help care providers decide what interventions most likely would lead to successful outcomes.
Collapse
|
87
|
Leblanc A, Day N, Ménard A, Keillor JW. Guinea pig liver transglutaminase: A modified purification procedure affording enzyme with superior activity in greater yield. Protein Expr Purif 1999; 17:89-95. [PMID: 10497073 DOI: 10.1006/prep.1999.1107] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tissue transglutaminase purified from guinea pig livers has a very broad substrate specificity in comparison with other members of the transglutaminase family and therefore is useful for substrate analogue kinetic studies. Modifications made in our laboratory to the standard purification protocol (J. E. Folk and S. I. Chung, 1985, Methods Enzymol. 113, 358-364) have yielded a 28% increase in specific activity and 55% increase in overall yield, while reducing the number of steps to the purification. Herein we report some of the highest yields and specific activities for guinea pig liver transglutaminase found in the literature, as well as the use of lyophilization as a solution to the long-standing problem of enzyme stability during storage.
Collapse
|
88
|
Day N, Keillor JW. A continuous spectrophotometric linked enzyme assay for transglutaminase activity. Anal Biochem 1999; 274:141-4. [PMID: 10527508 DOI: 10.1006/abio.1999.4255] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
89
|
Brown H, Hien TT, Day N, Mai NT, Chuong LV, Chau TT, Loc PP, Phu NH, Bethell D, Farrar J, Gatter K, White N, Turner G. Evidence of blood-brain barrier dysfunction in human cerebral malaria. Neuropathol Appl Neurobiol 1999; 25:331-40. [PMID: 10476050 DOI: 10.1046/j.1365-2990.1999.00188.x] [Citation(s) in RCA: 184] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Patients infected with the malaria parasite Plasmodium falciparum may develop a diffuse reversible encephalopathy, termed cerebral malaria. It is unclear how the intraerythrocytic parasite, which sequesters in the cerebral microvasculature but does not enter the brain parenchyma, induces this neurological syndrome. Adhesion of parasitized red blood cells in the brain microvasculature is mediated by specific receptors on the host endothelium, including intercellular adhesion molecule (ICAM)-1, CD36 and CD31. Leucocyte binding to cerebral endothelial cells in culture induces intracellular signalling via ICAM-1. The hypothesis that parasitized red blood cells binding to receptors on cerebral endothelial cells causes changes in the integrity of the blood-brain barrier was tested. Immunohistochemistry was used to examine the blood-brain barrier in human cerebral malaria, with antibodies to macrophage and endothelial activation markers, intercellular junction proteins, and plasma proteins. The distribution of the cell junction proteins occludin, vinculin and ZO-1 were altered in cerebral malaria cases compared to controls. While fibrinogen was the only plasma protein detected in the perivascular space, there was widespread perivascular macrophage activation, suggesting that these cells had been exposed to plasma proteins. It was concluded that functional changes to the blood-brain barrier occur in cerebral malaria, possibly as a result of the binding of parasitized red blood cells to cerebral endothelial cells. These changes require further examination in vitro.
Collapse
|
90
|
Trifillis P, Day N, Kiledjian M. Finding the right RNA: identification of cellular mRNA substrates for RNA-binding proteins. RNA (NEW YORK, N.Y.) 1999; 5:1071-1082. [PMID: 10445881 PMCID: PMC1369830 DOI: 10.1017/s1355838299981803] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Defects in RNA-binding proteins have been implicated in human genetic disorders. However, efforts in understanding the functions of these proteins have been hampered by the inability to obtain their mRNA substrates. To identify cognate cellular mRNAs associated with an RNA-binding protein, we devised a strategy termed isolation of specific nucleic acids associated with proteins (SNAAP). The SNAAP technique allows isolation and subsequent identification of these mRNAs. To assess the validity of this approach, we utilized cellular mRNA and protein from K562 cells and alphaCP1, a protein implicated in a-globin mRNA stability, as a model system. Immobilization of an RNA-binding protein with the glutathione-S-transferase (GST) domain enables isolation of mRNA within an mRNP context and the identity of the bound mRNAs is determined by the differential display assay. The specificity of protein-RNA interactions was considerably enhanced when the interactions were carried out in the presence of cellular extract rather than purified components. Two of the mRNAs specifically bound by alphaCP1 were mRNAs encoding the transmembrane receptor protein, TAPA-1, and the mitochondrial cytochrome c oxidase subunit II enzyme, coxII. A specific poly(C)-sensitive complex formed on the TAPA-1 and coxII 3' UTRs consistent with the binding of aCP1. Furthermore, direct binding of purified alphaCP proteins to these 3' UTRs was demonstrated and the binding sites determined. These results support the feasibility of the SNAAP technique and suggest a broad applicability for the approach in identifying mRNA targets for clinically relevant RNA-binding proteins that will provide insights into their possible functions.
Collapse
|
91
|
Davies C, Peacock S, Day N, Berendt A. Clinical correlates of adhesion and slime production in coagulase-negative staphylococcal prospthetic joint infection. J Infect 1999. [DOI: 10.1016/s0163-4453(99)90156-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
92
|
Day N, Phu N, Hien T, White N. The pathophysiological and prognostic significance of acidosis in severe adult malaria. J Infect 1999. [DOI: 10.1016/s0163-4453(99)90165-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
93
|
Wang Z, Day N, Trifillis P, Kiledjian M. An mRNA stability complex functions with poly(A)-binding protein to stabilize mRNA in vitro. Mol Cell Biol 1999; 19:4552-60. [PMID: 10373504 PMCID: PMC84253 DOI: 10.1128/mcb.19.7.4552] [Citation(s) in RCA: 206] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The stable globin mRNAs provide an ideal system for studying the mechanism governing mammalian mRNA turnover. alpha-Globin mRNA stability is dictated by sequences in the 3' untranslated region (3'UTR) which form a specific ribonucleoprotein complex (alpha-complex) whose presence correlates with mRNA stability. One of the major protein components within this complex is a family of two polycytidylate-binding proteins, alphaCP1 and alphaCP2. Using an in vitro-transcribed and polyadenylated alpha-globin 3'UTR, we have devised an in vitro mRNA decay assay which reproduces the alpha-complex-dependent mRNA stability observed in cells. Incubation of the RNA with erythroleukemia K562 cytosolic extract results in deadenylation with distinct intermediates containing a periodicity of approximately 30 nucleotides, which is consistent with the binding of poly(A)-binding protein (PABP) monomers. Disruption of the alpha-complex by sequestration of alphaCP1 and alphaCP2 enhances deadenylation and decay of the mRNA, while reconstitution of the alpha-complex stabilizes the mRNA. Similarly, PABP is also essential for the stability of mRNA in vitro, since rapid deadenylation resulted upon its depletion. An RNA-dependent interaction between alphaCP1 and alphaCP2 with PABP suggests that the alpha-complex can directly interact with PABP. Therefore, the alpha-complex is an mRNA stability complex in vitro which could function at least in part by interacting with PABP.
Collapse
|
94
|
Day N, Oakes S, Luben R, Khaw KT, Bingham S, Welch A, Wareham N. EPIC-Norfolk: study design and characteristics of the cohort. European Prospective Investigation of Cancer. Br J Cancer 1999; 80 Suppl 1:95-103. [PMID: 10466767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
|
95
|
Sala E, Warren R, McCann J, Duffy S, Day N, Luben R. Mammographic parenchymal patterns and mode of detection: implications for the breast screening programme. J Med Screen 1999; 5:207-12. [PMID: 9934652 DOI: 10.1136/jms.5.4.207] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To assess the effects of mammographic parenchymal patterns on the risk of breast cancer detected at first screen, second screen, and in the interval between these two screens. SETTINGS A nested case-control study within a screening cohort in East Anglia was designed. The study group comprised 502 patients with cancer at the prevalence screening round, 198 patients with interval cancer, and 175 with cancer at the first incidence screen. These patients were matched with 2601 controls. METHODS The mammographic parenchymal patterns of breast tissue were assessed according to Wolfe's classification. Statistical analysis was by conditional logistic regression. RESULTS Overall, 67% of patients and 59% of controls were considered to have high risk pattern (P2 + DY) mammogram. The risk associated with P2 or DY mammographic patterns compared with N1 was higher for interval cancers (odds ratios (ORs) 2.2 and 2.4 respectively) than for screen detected cancers (ORs 1.7 and 1.1 respectively). For interval cancers in the first 18 months after the last negative mammogram, the risk was particularly high (ORs 3.8 for P2 and 4.1 for DY compared with N1). The high risk associated with P2 and DY patterns was concentrated on invasive ductal grade III cancers (ORs 2.7 and 3.8) rather than grade I or II cancers (ORs 1.6 and 1.2). CONCLUSIONS The study strongly suggests that screening effectiveness is reduced for high risk parenchymal patterns which are associated with high grade cancers. Changes should aim at improving screening sensitivity for dense parenchymal patterns, and the diagnosis of high grade tumours.
Collapse
|
96
|
Huang X, Day N, Luo X, Roupioz Y, Seid M, Keillor JW. Synthesis and characterization of a series of novel glutamic gamma-15N-anilide dipeptides. THE JOURNAL OF PEPTIDE RESEARCH : OFFICIAL JOURNAL OF THE AMERICAN PEPTIDE SOCIETY 1999; 53:126-33. [PMID: 10195450 DOI: 10.1034/j.1399-3011.1999.00005.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The preparation of a series of novel Cbz-Gln-Gly dipeptide derivatives is reported, wherein the gamma-carboxamide groups of the glutamine side chains have been modified to gamma-15N-anilides which are substituted in the para position with -NO2, -Cl, -H, -CH3, -OCH3, and -N(CH3)2. Characterization of the free anilines (p(kappa)a values and 15N NMR chemical shifts) and corresponding gamma-anilides (15N NMR chemical shifts and FTIR wavenumbers) is also reported. Correlation of these physicochemical data to Hammett substituent parameters ((sigma)para) is discussed. These novel dipeptide derivatives should prove to be generally useful for structure-function enzymology studies of gamma-glutamyl transferring enzymes.
Collapse
|
97
|
Kiledjian M, Day N, Trifillis P. Purification and RNA binding properties of the polycytidylate-binding proteins alphaCP1 and alphaCP2. Methods 1999; 17:84-91. [PMID: 10075886 DOI: 10.1006/meth.1998.0710] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Regulation of mRNA turnover is a critical control mechanism of gene expression and is influenced by ribonucleoprotein (RNP) complexes that form on cis elements. All mRNAs have an intrinsic half-life and in many cases these half-lives can be altered by a variety of stimuli that are manifested through the formation or disruption of an RNP structure. The stability of alpha-globin mRNA is determined by elements in the 3' untranslated region that are bound by an RNP complex (alpha-complex) which appears to control the erythroid-specific accumulation of alpha-globin mRNA. The alpha-complex could consist of up to six distinct proteins or protein families. One of these families is a prominent polycytidylate binding activity which consists of two highly homologous proteins, alpha-complex proteins 1 and 2 (alphaCP1 and alphaCP2). This article focuses on various methodologies for the detection and manipulation of alphaCP1 and alphaCP2 binding to RNA and details means of isolating and characterizing mRNA bound by these proteins to study mRNA turnover and its regulation.
Collapse
|
98
|
Day N. The medical record. Your best friend or worst enemy? BALANCE (ALEXANDRIA, VA.) 1998; 2:9-13. [PMID: 10345250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
|
99
|
Christ GJ, Rehman J, Day N, Salkoff L, Valcic M, Melman A, Geliebter J. Intracorporal injection of hSlo cDNA in rats produces physiologically relevant alterations in penile function. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 275:H600-8. [PMID: 9683449 DOI: 10.1152/ajpheart.1998.275.2.h600] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The Ca2+-sensitive K+ channel (maxi-K+) is an important modulator of corporal smooth muscle tone. The goal of these studies was twofold: 1) to determine the feasibility of transfecting corporal smooth muscle cells in vivo with the hSlo cDNA, which encodes for the human smooth muscle maxi-K+ channel, and 2) to determine whether transfection of the maxi-K+ channel would affect the physiological response to cavernous nerve stimulation in a rat model in vivo. Intracorporal microinjection of pCMVbeta/Lac Z DNA in 10-wk-old rats resulted in significant incorporation and expression of beta-galactosidase activity in 10 of 12 injected animals for up to 75 days postinjection. Moreover, electrical stimulation of the cavernous nerve revealed that, relative to the responses obtained in age-matched control animals (N = 12), intracavernous injection of naked pcDNA/hSlo DNA was associated with a statistically significant elevation in the mean amplitude of the intracavernous pressure response at all levels of current stimulation (range 0.5-10 mA) at both 1 mo (N = 5) and 2 mo (N = 8) postinjection. Furthermore, qualitatively similar observations were made at 3 mo (N = 2) and 4 mo (N = 2) postinjection. These data indicate that naked hSlo DNA is quite easily incorporated into corporal smooth muscle and, furthermore, that expression is sustained for at least 2 mo in corporal smooth muscle cells in vivo. Finally, after expression, hSlo is capable of measurably altering nerve-stimulated penile erection. Taken together, these data provide compelling evidence for the potential utility of gene therapy in the treatment of erectile dysfunction.
Collapse
|
100
|
McCann J, Stockton D, Day N. Breast cancer in East Anglia: the impact of the breast screening programme on stage at diagnosis. J Med Screen 1998; 5:42-8. [PMID: 9575460 DOI: 10.1136/jms.5.1.42] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES To assess the impact of the National Health Service breast screening programme on overall and stage-specific incidence of breast cancer in East Anglia; also, to predict the magnitude of the screening induced reduction in breast cancer mortality. SETTING Women resident in East Anglia aged 50-69, diagnosed between 1976 and 1995. METHODS Comparison of numbers and incidence of breast cancer by age, stage, and mode of detection; investigation of relative contributions of advanced (stages II, III, and IV) cancers to total incidence by detection mode; estimation of the reduction in advanced cancer incidence. RESULTS There has been a large increase in early stage incidence in the age group 50-64 targeted by the screening programme. By 1995, the estimated decrease in advanced cancer incidence was between 7 and 19%. In 1995, of all breast cancers arising in the age group 50-69 years, 33% were screen detected, 27% were interval cancers, 15% were in non-attenders, 9% were in lapsed attenders, 7% occurred before invitation, and 4% arose in women outside the birth year range for invitation. Of the advanced cancers diagnosed in 1995, 31% were interval cancers, 20% were screen detected, 19% were in non-attenders, 12% were in lapsed attenders, 8% occurred before invitation, and 4% presented in women outside the birth year range for invitation. CONCLUSIONS Screening has brought about a large increase in detection of early stage cancers. This increase has not yet been fully matched by a corresponding deficit in advanced cancers, possibly because the full effect of screening has not yet been achieved. Reducing the proportion of interval cancers is necessary to increase the effect of screening on mortality.
Collapse
|