1
|
McDonnell T, Cosgrove G, Hogan E, Martin J, McNicholas T, O'Dowd M, Rizoaica F, McAuliffe E. Methods to derive composite indicators used for quality and safety measurement and monitoring in healthcare: a scoping review protocol. BMJ Open 2023; 13:e071382. [PMID: 37451716 PMCID: PMC10351297 DOI: 10.1136/bmjopen-2022-071382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Accepted: 06/21/2023] [Indexed: 07/18/2023] Open
Abstract
INTRODUCTION Composite indicators of quality and safety in healthcare summarise performance across multiple indicators into a single performance measure. Composite indicators can identify domains and drivers of quality, improve the ability to detect differences, aid prioritisation for quality improvement and facilitate decision making about future healthcare needs. However, the use of composite indicators can be controversial, particularly when used to rank healthcare providers. Many of the concerns around transparency, appropriateness and uncertainty may be addressed by a robust and transparent development and review process.The aim of this scoping review is to describe methodologies used at each of the stages of development of composite indicators of quality and safety in healthcare. This review will provide those tasked with developing or reviewing composite indicators with a valuable consolidated analysis of a substantial and wide-ranging literature. METHODS AND ANALYSIS The framework proposed by the Joanna Briggs Institute and enhancements proposed by Peters et al (2015, 2017, 2020) will be used in conducting this scoping review, and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis extension for scoping reviews will guide the reporting. Grey literature and peer-reviewed documents will be in-scope. Electronic databases (PubMed, Embase, CINAHL, ABI/INFORM and SafetyLit) will be searched, and publications will be screened by two reviewers. Discussion, policy and guidance publications will be included if they discuss any aspect of the methods used in the development of a composite indicator of quality or safety in a healthcare setting. The search period ranges from 1 January 2000 to 31 December 2022. Data extraction will capture information on 11 stages of composite indicator development, augmenting a 10-stage framework developed by the European Commission Joint Research Centre. ETHICS AND DISSEMINATION Ethical approval is not required. Review findings will be published in a peer-reviewed journal and presented at scientific conferences.
Collapse
Affiliation(s)
- Thérèse McDonnell
- IRIS Centre, School of Nursing, Midwifery and Health Systems, University College Dublin, Dublin, Ireland
| | - Grainne Cosgrove
- National Quality and Patient Safety Directorate, Health Service Executive, Dublin, Ireland
| | - Emma Hogan
- National Quality and Patient Safety Directorate, Health Service Executive, Dublin, Ireland
| | - Jennifer Martin
- National Quality and Patient Safety Directorate, Health Service Executive, Dublin, Ireland
| | - Triona McNicholas
- National Quality and Patient Safety Directorate, Health Service Executive, Dublin, Ireland
| | - Marcella O'Dowd
- National Quality and Patient Safety Directorate, Health Service Executive, Dublin, Ireland
| | - Florina Rizoaica
- National Quality and Patient Safety Directorate, Health Service Executive, Dublin, Ireland
| | - Eilish McAuliffe
- IRIS Centre, School of Nursing, Midwifery and Health Systems, University College Dublin, Dublin, Ireland
| |
Collapse
|
2
|
Carroll C, Conway R, O'Donnell D, Norton C, Hogan E, Browne M, Buckley CM, Kavanagh P, Martin J, Doyle S. Routine testing of close contacts of confirmed COVID-19 cases - National COVID-19 Contact Management Programme, Ireland, May to August 2020. Public Health 2020; 190:147-151. [PMID: 33386140 PMCID: PMC7577651 DOI: 10.1016/j.puhe.2020.10.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 10/10/2020] [Indexed: 01/16/2023]
Abstract
OBJECTIVES The objective of this study was to inform public health practitioners who are designing, adapting and implementing testing and tracing strategies for Coronavirus disease (COVID-19) control. STUDY DESIGN The study design is monitoring and evaluation of a national public health protection programme. METHODS All close contacts of laboratory-confirmed cases of COVID-19 identified between the 19th May and 2nd August were included; secondary attack rates and numbers needed to test were estimated. RESULTS Four thousand five hundred eighty six of 7272 (63%) close contacts of cases were tested with at least one test. The secondary attack rate in close contacts who were tested was 7% (95% Confidence Interval [CI]: 6.3 - 7.8%). At the 'day 0' test, 14.6% (95% CI: 11.6-17.6%) of symptomatic close contacts tested positive compared with 5.2% (95% CI: 4.4-5.9%) of asymptomatic close contacts. CONCLUSIONS The application of additional symptom-based criteria for testing in this high-incidence population (close contacts) is of limited utility because of the low negative predictive value of absence of symptoms.
Collapse
Affiliation(s)
- C Carroll
- Joint First Author; COVID-19 Contact Management Programme, Health Service Executive, Ireland
| | - R Conway
- Joint First Author; COVID-19 Contact Management Programme, Health Service Executive, Ireland.
| | - D O'Donnell
- COVID-19 Contact Management Programme, Health Service Executive, Ireland
| | - C Norton
- COVID-19 Contact Management Programme, Health Service Executive, Ireland
| | - E Hogan
- COVID-19 Contact Management Programme, Health Service Executive, Ireland; National Quality Improvement Team, Health Service Executive, Ireland
| | - M Browne
- COVID-19 Contact Management Programme, Health Service Executive, Ireland; National Quality Improvement Team, Health Service Executive, Ireland
| | - C M Buckley
- COVID-19 Contact Management Programme, Health Service Executive, Ireland; School of Public Health, University College Cork, Cork, Ireland
| | - P Kavanagh
- COVID-19 Contact Management Programme, Health Service Executive, Ireland; Health Intelligence Unit Strategic Planning and Transformation, Dublin, Ireland; Division of Population Health Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - J Martin
- COVID-19 Contact Management Programme, Health Service Executive, Ireland; National Quality Improvement Team, Health Service Executive, Ireland
| | - S Doyle
- COVID-19 Contact Management Programme, Health Service Executive, Ireland
| |
Collapse
|
3
|
Lindstrom H, Kearney L, Massey D, Godsall G, Hogan E. How midwives manage rapid pre-loading of fluid in women prior to low dose epidurals: A retrospective chart review. J Adv Nurs 2018; 74:2588-2595. [DOI: 10.1111/jan.13783] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2018] [Indexed: 11/30/2022]
Affiliation(s)
- Hannah Lindstrom
- Sunshine Coast Hospital and Health Service; Britinya QLD Australia
| | - Lauren Kearney
- Sunshine Coast Hospital and Health Service; Britinya QLD Australia
- University of the Sunshine Coast; Sippy Downs QLD Australia
| | - Debbie Massey
- University of the Sunshine Coast; Sippy Downs QLD Australia
| | - Guy Godsall
- Sunshine Coast Hospital and Health Service; Britinya QLD Australia
| | - Emma Hogan
- Sunshine Coast Hospital and Health Service; Britinya QLD Australia
| |
Collapse
|
4
|
Ralph A, Somers M, Cowman J, Voisin B, Hogan E, Dunne H, Dunne E, Byrne B, Kent N, Ricco AJ, Kenny D, Wong S. Computational Tracking of Shear-Mediated Platelet Interactions with von Willebrand Factor. Cardiovasc Eng Technol 2016; 7:389-405. [PMID: 27743349 DOI: 10.1007/s13239-016-0282-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 10/07/2016] [Indexed: 01/01/2023]
Abstract
The imaging of shear-mediated dynamic platelet behavior interacting with surface-immobilized von Willebrand factor (vWF) has tremendous potential in characterizing changes in platelet function for clinical diagnostics purposes. However, the imaging output, a series of images representing platelets adhering and rolling on the surface, poses unique, non-trivial challenges for software algorithms that reconstruct the positional trajectories of platelets. We report on an algorithm that tracks platelets using the output of such flow run experiments, taking into account common artifacts encountered by previously-published methods, and we derive seven key metrics of platelet dynamics that can be used to characterize platelet function. Extensive testing of our method using simulated platelet flow run data was carried out to validate our tracking method and derived metrics in capturing key platelet-vWF interaction-dynamics properties. Our results show that while the number of platelets present on the imaged area is the leading cause of errors, flow run data from two experiments using whole blood samples showed that our method and metrics can detect platelet property changes/differences that are concordant with the expected biological outcome, such as inhibiting key platelet receptors such as P2Y1, glycoprotein (GP)Ib and GPIIb/IIIa. These findings support the use of our methodologies to characterize platelet function among a wide range of healthy and disease cohorts.
Collapse
Affiliation(s)
- Adam Ralph
- Irish Centre for High-End Computing, IT Building, National University of Ireland, University Road, Galway, Ireland
| | - Martin Somers
- Biomedical Diagnostics Institute, Dublin City University, Dublin 9, Ireland
| | - Jonathan Cowman
- Biomedical Diagnostics Institute, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Bruno Voisin
- Irish Centre for High-End Computing, IT Building, National University of Ireland, University Road, Galway, Ireland
| | - Emma Hogan
- Irish Centre for High-End Computing, IT Building, National University of Ireland, University Road, Galway, Ireland
| | - Hannah Dunne
- Biomedical Diagnostics Institute, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Eimear Dunne
- Biomedical Diagnostics Institute, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Barry Byrne
- Biomedical Diagnostics Institute, Dublin City University, Dublin 9, Ireland
| | - Nigel Kent
- School of Mechanical and Design Engineering, Dublin Institute of Technology, Bolton Street, Dublin 1, Ireland
| | - Antonio J Ricco
- Biomedical Diagnostics Institute, Dublin City University, Dublin 9, Ireland
| | - Dermot Kenny
- Biomedical Diagnostics Institute, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Simon Wong
- Irish Centre for High-End Computing, IT Building, National University of Ireland, University Road, Galway, Ireland.
| |
Collapse
|
5
|
Hogan E, Woods C, Buttrose M, Abenthum L, Cheng HC, de Costa C. The changing birth suite experience for Australian medical students. Aust N Z J Obstet Gynaecol 2016; 56:537-542. [PMID: 27464475 DOI: 10.1111/ajo.12495] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 05/26/2016] [Indexed: 11/29/2022]
Abstract
Competition with midwifery students, combined with increasing numbers of medical students, has led to declining standards of clinical experience in the birth suite for our senior medical students. In the Australian setting, increased and improved communication and collaboration between the two disciplines is urgently needed to rectify the situation.
Collapse
Affiliation(s)
- Emma Hogan
- Queensland Health, Cairns Hospital, Cairns, Queensland, Australia
| | - Cindy Woods
- James Cook University, College of Medicine and Dentistry, Cairns Clinical School, Cairns, Queensland, Australia.
| | - Maryke Buttrose
- James Cook University, College of Medicine and Dentistry, Cairns Clinical School, Cairns, Queensland, Australia
| | - Linda Abenthum
- Queensland Health, Cairns Hospital, Cairns, Queensland, Australia
| | - Hon C Cheng
- James Cook University, College of Medicine and Dentistry, Cairns Clinical School, Cairns, Queensland, Australia
| | - Caroline de Costa
- James Cook University, College of Medicine and Dentistry, Cairns Clinical School, Cairns, Queensland, Australia
| |
Collapse
|
6
|
Scheeres K, Tovey M, Hogan E, Ryland H. Why become a trainee representative? Assoc Med J 2015. [DOI: 10.1136/bmj.h974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
7
|
Abstract
INTRODUCTION Proboscis lateralis is a rare congenitally acquired facial abnormality characterized by a soft-tissue tube- or trunk-like appendage projecting from the surface of the face, most frequently rooted in the medial canthal region. Proboscis lateralis is generally associated with a wide range of concomitant craniofacial anomalies, giving rise to multiple theories describing the embryological pathogenesis and various classification systems to account for the pathological associations. RESULTS/CONCLUSION This paper provides a literature review of the rare manifestations of proboscis lateralis and represents a summary of current literature related to embryological pathogenesis, definitive diagnosis, and surgical management approaches.
Collapse
Affiliation(s)
- S Martin
- Department of Anatomical Sciences, School of Medicine, St. George's University, Grenada, West Indies
| | | | | | | | | | | |
Collapse
|
8
|
Zentall TR, Hogan E. Same/different concept learning in the pigeon: the effect of negative instances and prior adaptation to transfer stimuli. J Exp Anal Behav 2010; 30:177-86. [PMID: 16812097 PMCID: PMC1332713 DOI: 10.1901/jeab.1978.30-177] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Pigeons were trained on a matching-to-sample or oddity-from-sample task with shapes (circle and plus). Half of each group was exposed to "negative instance" trials i.e., for matching birds, neither comparison key matched the sample, and for oddity birds both comparison keys matched the sample. When all birds were transferred to a new task involving colors (red and green), nonshifted birds (transferred from matching to matching, or oddity to oddity) performed significantly better than shifted birds (transferred from matching to oddity, or oddity to matching), but only if they had experienced negative instances of the training concept. When all birds were exposed to negative instances of the transfer task and then transferred to a new color task (yellow and blue), dramatic transfer effects were observed. The effect of pre-exposure to the yellow and blue colors, in order to reduce transfer-stimulus novelty, had a minor effect on transfer.
Collapse
|
9
|
|
10
|
Burleigh MR, Hogan E, Dobbie PD, Napiwotzki R, Maxted PFL. A near-infrared spectroscopic detection of the brown dwarf in the post common envelope binary WD 0137-349. ACTA ACUST UNITED AC 2006. [DOI: 10.1111/j.1745-3933.2006.00242.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
11
|
Tarpey I, Orbell SJ, Britton P, Casais R, Hodgson T, Lin F, Hogan E, Cavanagh D. Safety and efficacy of an infectious bronchitis virus used for chicken embryo vaccination. Vaccine 2006; 24:6830-8. [PMID: 16860445 PMCID: PMC7126498 DOI: 10.1016/j.vaccine.2006.06.040] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2006] [Revised: 06/19/2006] [Accepted: 06/20/2006] [Indexed: 11/28/2022]
Abstract
Commercial vaccines for in ovo vaccination have not yet been developed for infectious bronchitis virus (IBV), the major coronavirus in the poultry industry. Recombinant IBVs based on the Beaudette strain expressing the Beaudette spike protein (Beau-R) or that from the virulent M41 strain (BeauR-M41(S)) were assessed for their potential as prototype vaccines for application to 18-day-old embryos. Pathogenicity was assessed by observing the effect on hatchability, and/or the production of nasal discharge and/or the effects on ciliary activity in the trachea at various time points post hatch. In contrast to commercial IBV vaccines given in ovo, the Beau-R and BeauR-M41(S) strains did not reduce hatchability or cause nasal discharge, and caused minimal damage to the ciliated epithelium of the trachea. The presence of the spike protein from a virulent virus did not increase the pathogenicity of the virus according to the criteria used. Assessment of the BeauR-M41(S) strain for efficacy showed that it protected up to 90% of chicks against challenge with virulent IB virus (M41) in a dose dependent manner. Further egg passage of the BeauR-M41(S) strain (BeauR-M41(S) EP10) did not increase its pathogenicity though it did improve its efficacy, based on serology and protection against a virulent challenge. BeauR-M41(S) EP10 was more efficacious than BeauR-M41(S) protecting more birds against virulent challenge and providing a better serological antibody response. BeauR-M41(S) EP10 induced a serological response similar to that of a commercial vaccine given at day-old though the commercial vaccine provided slightly higher efficacy. These results are promising for the development of embryo safe efficacious IBV vaccines for in ovo application.
Collapse
Affiliation(s)
- I Tarpey
- Intervet UK, Walton Manor, Walton, Milton Keynes, Bucks, UK.
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Foster N, Holland H, Hogan E. Improving the quality of the health care work place: implications for workers and patients. Introduction. Jt Comm J Qual Improv 2001; 27:443. [PMID: 11556253 DOI: 10.1016/s1070-3241(01)27038-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- N Foster
- Agency for Healthcare Research and Quality, 2101 E. Jefferson St, Suite 600, Rockville, MD 20852, USA.
| | | | | |
Collapse
|
13
|
Abstract
Although general features of chromosome movement during the cell cycle are conserved among all eukaryotic cells, particular aspects vary between organisms. Understanding the basis for these variations should provide significant insight into the mechanism of chromosome movement. In this context, establishing the types of chromosome movement in the budding yeast Saccharomyces cerevisiae is important since the complexes that mediate chromosome movement (microtubule organizing centers, spindles, and kinetochores) appear much simpler in this organism than in many other eukaryotic cells. We have used fluorescence in situ hybridization to begin an analysis of chromosome movement in budding yeast. Our results demonstrate that the position of yeast centromeres changes as a function of the cell cycle in a manner similar to other eukaryotes. Centromeres are skewed to the side of the nucleus containing the spindle pole in G1; away from the poles in mid-M and clustered near the poles in anaphase and telophase. The change in position of the centromeres relative to the spindle poles supports the existence of anaphase A in budding yeast. In addition, an anaphase A-like activity independent of anaphase B was demonstrated by following the change in centromere position in telophase-arrested cells upon depolymerization and subsequent repolymerization of microtubules. The roles of anaphase A activity and G1 centromere positioning in the segregation of budding yeast chromosomes are discussed. The fluorescence in situ hybridization methodology and experimental strategies described in this study provide powerful new tools to analyze mutants defective in specific kinesin-like molecules, spindle components, and centromere factors, thereby elucidating the mechanism of chromosome movement.
Collapse
Affiliation(s)
- V Guacci
- Department of Embryology, Carnegie Institution of Washington, Baltimore, Maryland 21210, USA
| | | | | |
Collapse
|
14
|
Hogan E. Diagnosis and Management of Disorders of the Spinal Cord. Neurology 1997. [DOI: 10.1212/wnl.48.2.559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
15
|
Strunnikov AV, Hogan E, Koshland D. SMC2, a Saccharomyces cerevisiae gene essential for chromosome segregation and condensation, defines a subgroup within the SMC family. Genes Dev 1995; 9:587-99. [PMID: 7698648 DOI: 10.1101/gad.9.5.587] [Citation(s) in RCA: 287] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We characterized the SMC2 (structural maintenance of chromosomes) gene that encodes a new Saccharomyces cerevisiae member of the growing family of SMC proteins. This family of evolutionary conserved proteins was introduced with identification of SMC1, a gene essential for chromosome segregation in budding yeast. The analysis of the putative structure of the Smc2 protein (Smc2p) suggests that it defines a distinct subgroup within the SMC family. This subgroup includes the ScII, XCAPE, and cut14 proteins characterized concurrently. Smc2p is a nuclear, 135-kD protein that is essential for vegetative growth. The temperature-sensitive mutation, smc2-6, confers a defect in chromosome segregation and causes partial chromosome decondensation in cells arrested in mitosis. The Smc2p molecules are able to form complexes in vivo both with Smc1p and with themselves, suggesting that they can assemble into a multimeric structure. In this study we present the first evidence that two proteins belonging to two different subgroups within the SMC family carry nonredundant biological functions. Based on genetic, biochemical, and evolutionary data we propose that the SMC family is a group of prokaryotic and eukaryotic chromosomal proteins that are likely to be one of the key components in establishing the ordered structure of chromosomes.
Collapse
Affiliation(s)
- A V Strunnikov
- Carnegie Institution of Washington, Department of Embryology, Baltimore, Maryland 21210
| | | | | |
Collapse
|
16
|
Abstract
We have developed a fluorescent in situ hybridization (FISH) method to examine the structure of both natural chromosomes and small artificial chromosomes during the mitotic cycle of budding yeast. Our results suggest that the pairing of sister chromatids: (a) occurs near the centromere and at multiple places along the chromosome arm as has been observed in other eukaryotic cells; (b) is maintained in the absence of catenation between sister DNA molecules; and (c) is independent of large blocks of repetitive DNA commonly associated with heterochromatin. Condensation of a unique region of chromosome XVI and the highly repetitive ribosomal DNA (rDNA) cluster from chromosome XII were also examined in budding yeast. Interphase chromosomes were condensed 80-fold relative to B form DNA, similar to what has been observed in other eukaryotes, suggesting that the structure of interphase chromosomes may be conserved among eukaryotes. While additional condensation of budding yeast chromosomes were observed during mitosis, the level of condensation was less than that observed for human mitotic chromosomes. At most stages of the cell cycle, both unique and repetitive sequences were either condensed or decondensed. However, in cells arrested in late mitosis (M) by a cdc15 mutation, the unique DNA appeared decondensed while the repetitive rDNA region appeared condensed, suggesting that the condensation state of separate regions of the genome may be regulated differently. The ability to monitor the pairing and condensation of sister chromatids in budding yeast should facilitate the molecular analysis of these processes as well as provide two new landmarks for evaluating the function of important cell cycle regulators like p34 kinases and cyclins. Finally our FISH method provides a new tool to analyze centromeres, telomeres, and gene expression in budding yeast.
Collapse
Affiliation(s)
- V Guacci
- Department of Embryology, Carnegie Institution of Washington, Baltimore, Maryland 21210
| | | | | |
Collapse
|
17
|
Guacci V, Yamamoto A, Strunnikov A, Kingsbury J, Hogan E, Meluh P, Koshland D. Structure and function of chromosomes in mitosis of budding yeast. Cold Spring Harb Symp Quant Biol 1993; 58:677-85. [PMID: 7956084 DOI: 10.1101/sqb.1993.058.01.075] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- V Guacci
- Department of Embryology, Carnegie Institute of Washington, Baltimore, Maryland 21210
| | | | | | | | | | | | | |
Collapse
|
18
|
Hogan E, Koshland D. Addition of extra origins of replication to a minichromosome suppresses its mitotic loss in cdc6 and cdc14 mutants of Saccharomyces cerevisiae. Proc Natl Acad Sci U S A 1992; 89:3098-102. [PMID: 1557417 PMCID: PMC48811 DOI: 10.1073/pnas.89.7.3098] [Citation(s) in RCA: 112] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Many cell division cycle (cdc) mutants of Saccharomyces cerevisiae exhibit elevated mitotic loss of pDK243, a 14-kilobase minichromosome with a centromere and one autonomous replicating sequence (ARS). Tandem copies of different ARSs were added to pDK243. The addition of these ARS clusters to pDK243 had no effect on its mitotic loss in cdc7 (protein kinase), cdc9 (DNA ligase), or cdc16 or cdc17 (DNA polymerase) mutants. However, in cdc6 and cdc14 mutants, the mitotic loss of pDK243 with an ARS cluster was suppressed by a factor of 6-8 compared to pDK243 without the cluster. This suppression was dependent upon the number of ARSs in the cluster and the integrity of the ARS consensus sequence in each ARS of the cluster. ARSs are known to be DNA replication origins. Therefore, the suppression of mini-chromosome loss by ARSs in cdc6 and cdc14 mutants suggests that these mutants are defective in the initiation of DNA replication. Since the CDC6 protein appears to act at the G1/S phase transition, the CDC6 protein may be a factor required at the beginning of S phase to initiate DNA replication at origins. In contrast, the CDC14 protein acts after mitosis. We suggest that the CDC14 protein performs a function late in the cell cycle that may be required for efficient initiation of DNA replication during S phase of the next cell cycle.
Collapse
Affiliation(s)
- E Hogan
- Department of Embryology, Carnegie Institute of Washington, Baltimore, MD 21210
| | | |
Collapse
|
19
|
Sethi N, Monteagudo MC, Koshland D, Hogan E, Burke DJ. The CDC20 gene product of Saccharomyces cerevisiae, a beta-transducin homolog, is required for a subset of microtubule-dependent cellular processes. Mol Cell Biol 1991; 11:5592-602. [PMID: 1922065 PMCID: PMC361930 DOI: 10.1128/mcb.11.11.5592-5602.1991] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Previous analysis of cdc20 mutants of the yeast Saccharomyces cerevisiae suggests that the CDC20 gene product (Cdc20p) is required for two microtubule-dependent processes, nuclear movements prior to anaphase and chromosome separation. Here we report that cdc20 mutants are defective for a third microtubule-mediated event, nuclear fusion during mating of G1 cells, but appear normal for a fourth microtubule-dependent process, nuclear migration after DNA replication. Therefore, Cdc20p is required for a subset of microtubule-dependent processes and functions at multiple stages in the life cycle. Consistent with this interpretation, we find that cdc20 cells arrested by alpha-factor or at the restrictive temperature accumulate anomalous microtubule structures, as detected by indirect immunofluorescence. The anomalous microtubule staining patterns are due to cdc20 because intragenic revertants that revert the temperature sensitivity have normal microtubule morphologies. cdc20 mutants have a sevenfold increase in the intensity of antitubulin fluorescence in intranuclear spindles compared with spindles from wild-type cells, yet the total amount of tubulin is indistinguishable by Western immunoblot analysis. This result suggests that Cdc20p modulates microtubule structure in wild-type cells either by promoting microtubule disassembly or by altering the surface of the microtubules. Finally, we cloned and sequenced CDC20 and show that it encodes a member of a family of proteins that share homology to the beta subunit of transducin.
Collapse
Affiliation(s)
- N Sethi
- Department of Biology, University of Virginia, Charlottesville 22901
| | | | | | | | | |
Collapse
|
20
|
Abstract
In the yeast, Saccharomyces cerevisiae, cell division cycle (CDC) genes have been identified whose products are required for the execution of different steps in the cell cycle. In this study, the fidelity of transmission of a 14-kb circular minichromosome and a 155-kb linear chromosome fragment was examined in cell divisions where specific CDC products were temporarily inactivated with either inhibitors, or temperature sensitive mutations in the appropriate CDC gene. All of the cdc mutants previously shown to induce loss of endogenous linear chromosomes also induced loss of a circular minichromosome and a large linear chromosome fragment in our study (either 1:0 or 2:0 loss events). Therefore, the efficient transmission of these artificial chromosomes depends upon the same trans factors that are required for the efficient transmission of endogenous chromosomes. In a subset of cdc mutants (cdc6, cdc7 and cdc16), the rate of minichromosome loss was significantly greater than the rate of loss of the linear chromosome fragment, suggesting that a structural feature of the minichromosome (nucleotide content, length or topology) makes the minichromosome hypersensitive to the level of function of these CDC gene products. In another subset of cdc mutants (cdc7 and cdc17), the relative rate of 1:0 events to 2:0 events differed for the minichromosome and chromosome fragment, suggesting that the type of chromosome loss event observed in these mutants was dependent upon chromosome structure. Finally, we show that 2:0 events for the minichromosome can occur by both a RAD52 dependent and RAD52 independent mechanism. These results are discussed in the context of the molecular functions of the CDC products.
Collapse
Affiliation(s)
- R E Palmer
- Department of Population Dynamics, Johns Hopkins University School of Hygiene and Public Health, Baltimore, Maryland 21205
| | | | | |
Collapse
|
21
|
Abstract
The regulation of intracellular pH (pHi) is essential for normal cell function, and controlled changes in pHi may play a central role in cell activation. Sodium-dependent Cl-HCO3 exchange is the dominant mechanism of pHi regulation in the invertebrate cells examined, and also occurs in mammalian cells. The transporter extrudes acid from the cell by exchanging extracellular Na+ and HCO3- (ref. 9) (or a related species) for intracellular Cl- (refs 3, 4). It is blocked by the stilbene derivatives DIDS (4,4'-diisothiocyano-stilbene-2,2'-disulphonate, ref. 10) and SITS (4-acetamido-4'-isothiocyano-stilbene-2,2'-disulphonate, ref. 3), and has a stoichiometry of two intracellular H+ neutralized for each Na+ taken up and each Cl- extruded by the axon. Because the inwardly-directed Na+ concentration gradient is sufficiently large to energize both the HCO3- influx and Cl- efflux, this electroneutral exchanger could be a classic secondary active transporter, thermodynamically independent of ATP hydrolysis. However, at least in the squid axon, the exchanger has an absolute requirement for ATP (ref. 3). Thus, a major unresolved issue is whether this Na-dependent Cl-HCO3 exchanger stoichiometrically hydrolyses ATP (the pump hypothesis), or whether ATP activates the transporter by a mechanism such as phosphorylation or simple binding (the activation hypothesis). We have now explored the role of ATP in pHi regulation by dialysing axons with the ATP analogue ATP-gamma-S. In many systems, ATP-gamma-S is an acceptable substrate for protein kinases, whereas the resulting thiophosphorylated proteins are not as readily hydrolysed by phosphatases as are phosphorylated proteins. Our results rule out the pump hypothesis, and show that the basis of the axon's ATP requirement is the pH-dependent activation (by, for instance, phosphorylation or ATP binding) of the exchanger itself, or of an essential activator.
Collapse
Affiliation(s)
- W F Boron
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut 06510
| | | | | |
Collapse
|
22
|
Ward S, Burke DJ, Sulston JE, Coulson AR, Albertson DG, Ammons D, Klass M, Hogan E. Genomic organization of major sperm protein genes and pseudogenes in the nematode Caenorhabditis elegans. J Mol Biol 1988; 199:1-13. [PMID: 3351915 DOI: 10.1016/0022-2836(88)90374-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The major sperm proteins (MSPs) are a family of closely related, small, basic proteins comprising 15% of the protein in Caenorhabditis elegans sperm. They are encoded by a multigene family of more than 50 genes, including many pseudogenes. MSP gene transcription occurs only in late primary spermatocytes. In order to study the genomic organization of transcribed MSP genes, probes specific for the 3' untranslated regions of sequenced cDNA clones were used to isolate transcribed genes from genomic libraries. These and other clones of MSP genes were located in overlapping cosmid clones by DNA fingerprinting. These cosmids were aligned with the genetic map by overlap with known genes or in-situ hybridization to chromosomes. Of 40 MSP genes identified, 37, including all those known to be transcribed, are organized into six clusters composed of 3 to 13 genes each. Within each cluster, MSP genes are not in tandem but are separated by at least several thousand bases of DNA. Pseudogenes are interspersed among functional genes. Genes with similar 3' untranslated sequences are in the same cluster. The six MSP clusters are confined to only three chromosomal loci; one on the left arm of chromosome II and two near the middle of chromosome IV. Additional sperm-specific genes are located in one cluster of MSP genes on chromosome IV. The multiplicity of MSP genes appears to be a mechanism for enhancing MSP synthesis in spermatocytes, and the loose clustering of genes could be a result of the mechanism of gene duplication or could play a role in regulation.
Collapse
Affiliation(s)
- S Ward
- Department of Embryology, Carnegie Institution of Washington, Baltimore, MD 21210
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Abstract
1. Proton nuclear magnetic resonance spectroscopy (1H NMR) was used to measure the major intracellular metabolites in perchloric acid extracts of the Macrobdella decora muscle and nervous systems and the Oryctolagus cuniculus cerebrum. 2. Acetate, alanine, choline, glutamate, inositol, and lactate were assigned in the spectrum of leech ventral cord, leech muscle, and rabbit cerebrum. 3. Hirudonine and propionate were clearly observed only in the spectrum of leech muscle. 4. Creatine, N-acetyl aspartate, gamma aminobutyric acid, aspartate, and taurine, distinctive components of spectra of the mammalian cerebrum, were not seen in the invertebrate spectra. 5. 1H NMR spectroscopy provides a simple and rapid means of characterizing the major organic metabolites found in leech muscle and nervous tissues.
Collapse
Affiliation(s)
- O A Petroff
- Department of Neurology, Yale University, School of Medicine, New Haven, CT 06510
| | | | | | | |
Collapse
|
24
|
Ward S, Roberts TM, Strome S, Pavalko FM, Hogan E. Monoclonal antibodies that recognize a polypeptide antigenic determinant shared by multiple Caenorhabditis elegans sperm-specific proteins. J Biophys Biochem Cytol 1986; 102:1778-86. [PMID: 2422180 PMCID: PMC2114204 DOI: 10.1083/jcb.102.5.1778] [Citation(s) in RCA: 71] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Four monoclonal antibodies that are directed against antigens present in sperm and absent from other worm tissues were characterized. Antibody TR20 is directed against the major sperm proteins, a family of small, abundant, cytoplasmic proteins that have been previously described (Klass, M. R., and D. Hirsh, 1981, Dev. Biol., 84:299-312; Burke, D. J., and S. Ward, 1983, J. Mol. Biol., 171:1-29). Three other antibodies, SP56, SP150, and TR11, are all directed against the same set of minor sperm polypeptides that range in size from 29 to 215 kD. More than eight different sperm polypeptides are antigenic by both immunotransfer and immunoprecipitation assays. The three antibodies are different immunoglobulin subclasses, yet they compete with each other for antigen binding so they are directed against the same antigenic determinant on the multiple sperm proteins. This antigenic determinant is sensitive to any of six different proteases, is insensitive to periodate oxidation or N-glycanase digestion, and is detectable on a polypeptide synthesized in vitro. Therefore, the antigenic determinant resides in the polypeptide chain. However, peptide fragments of the proteins are not antigenic, thus the determinant is likely to be dependent on polypeptide conformation. The antigenic determinant shared by these proteins could represent a common structural feature of importance to the localization or cellular specificity of these proteins.
Collapse
|
25
|
Hogan E. The unique function of nursing. N Z Nurs J 1985; 78:28-9. [PMID: 3860771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
26
|
Abstract
Spermiogenesis in nematodes involves the activation of sessile spherical spermatids to motile bipolar amoeboid spermatozoa. In Caenorhabditis elegans males spermiogenesis is normally induced by copulation. Spermatids transferred to hermaphrodites as well as some of those left behind in the male become spermatozoa a few minutes after mating. Spermiogenesis can also be induced in vitro by the ionophore monensin (G.A. Nelson and S. Ward, 1980, Cell 19, 457-464) and by weak bases such as triethanolamine. Both triethanolamine and monensin cause a rapid increase in intracellular pH from 7.1 to 7.5 or 8.0. This pH increase precedes the subsequent morphological events of spermiogenesis. Triethanolamine or monensin must be present throughout spermiogenesis for all cells to form pseudopods, but once pseudopods are formed the inducers are unnecessary for subsequent motility. The pH induced spermiogenesis is inhibited by drugs that block mitochondria or glycolysis. Protease treatment can also induce spermiogenesis without increasing intracellular pH, apparently bypassing the pH-dependent steps in activation and the requirement for glycolysis. These results show that the initiation of spermiogenesis in C. elegans, like some steps in egg activation and the initiation of sea urchin sperm motility, can be induced by an increase in intracellular pH, but this pH change can be bypassed by proteolysis.
Collapse
|
27
|
Kirkcaldy-Hargreaves M, Casey A, Hogan E, Mulroney R. Utility of an on-line computer system in a clinical setting for nutrient intake analyses. J Can Diet Assoc 1980; 41:112-7, 122-7. [PMID: 10248685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
The present report describes a four-week trial at the Victoria General Hospital, Halifax, to determine the effect of access to a computer system on nutrient intake analyses, the problems in implementation of the system, and the response of the staff dietitians. An on-line system was obtained from the Ohio State University Hospitals and modified to reflect Canadian food and nutrient content, and to include some additional program features. Twelve hundred and eighty-six foods were characterized according to 15 food components, the system was responsive to nine interactive commands, and there were nine possible print-out formats of calculations. The results of the trial reinforced the expectation of greatly increased work efficiency, however, the system was not utilized to its potential. Some technical problems were largely overcome within the first week of operation. However, needs relating to the extensiveness of the food and nutrient data base, and the methodologies and time for obtaining and evaluating individual dietary intake information prevented maximum efficiency. The dietitians liked the comprehensiveness and detail of the system, however, routine dietary intake collections were too time-consuming for their present work schedules.
Collapse
|
28
|
Abstract
The defect in myelinogenesis present in the Quaking mutant mouse was investigated using a double radioisotope technique for comparing the incorporation of amino acid into myelin proteins of normal and mutant mice. Quaking mice and littermate controls received intracranial injections of 150 muCi [3H]glycine and 25 muCi of [14C]glycine respectively. After 2 h their brains were combined and jointly processed to obtain subcellular fractions. The 3H/14C ratio for the myelin subfraction was 1.88 as compared to a 3H/14C ratio of 3.0 for the other subfractions, indicating a 40% decrease in glycine incorporation into myelin of Quaking mice. Myelin proteins were separated by discontinuous gel electrophoresis in the presence of sodium dodecyl sulfate (SDS) and the 3H/14C ratios determined in each gel slice. In contrast to the microsomal subfractions which gave a 3H/14C ratio of 2.6 across the gel, the 3H/14C ratio of myelin showed large variations with values ranging from 0.54 for proteolipid protein to 2.0 for some of the high molecular weight proteins. During development, the Quaking mutant exhibited a preferential depression in glycine incorporation into proteolipid protein in 18-day-old mice, while in older animals (32-54 days) the fast migrating basic protein, as well as the proteolipid protein, was labeled to a significantly lesser extent.
Collapse
|