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Melchers M, Matthews K, van Montfort T, Bontjer I, Eggink D, de Vries R, Michael E, David K, Moore JP, Berkhout B, Sanders RW. P05-05. Enhanced immunogenicity of HIV-1 envelope glycoprotein trimers fused to CD40 ligand. Retrovirology 2009. [PMCID: PMC2767986 DOI: 10.1186/1742-4690-6-s3-p81] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Stone J, Carson A, Duncan R, Coleman R, Roberts R, Warlow C, Hibberd C, Murray G, Cull R, Pelosi A, Cavanagh J, Matthews K, Goldbeck R, Smyth R, Walker J, MacMahon A, Sharpe M. Symptoms ‘unexplained by organic disease’ in 1144 new neurology out-patients: how often does the diagnosis change at follow-up? Brain 2009; 132:2878-88. [DOI: 10.1093/brain/awp220] [Citation(s) in RCA: 211] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Matthews K, Cauley J, Yaffe K, Zmuda JM. Estrogen replacement therapy and cognitive decline in older community women. Climacteric 2009. [DOI: 10.3109/13697139909038080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Eley J, Hogstrom K, Matthews K, Parker B, Price M. SU-FF-T-134: Segmented Field Electron Conformal Therapy with An Electron Multi-Leaf Collimator. Med Phys 2009. [DOI: 10.1118/1.3181608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Matthews K, Stelmackowich C. Anatomists' work song. CMAJ 2009. [DOI: 10.1503/cmaj.090062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Bromberger JT, Kravitz HM, Matthews K, Youk A, Brown C, Feng W. Predictors of first lifetime episodes of major depression in midlife women. Psychol Med 2009; 39:55-64. [PMID: 18377672 PMCID: PMC2905863 DOI: 10.1017/s0033291708003218] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
BACKGROUND Little is known about factors that predict first lifetime episodes of major depression in middle-aged women. It is not known whether health-related factors and life stress pose more or less of a risk to the onset of clinical depression than does the menopausal transition. METHOD The Structured Clinical Interview for DSM-IV Axis I Disorders (SCID) was used to assess diagnoses of lifetime, annual and current major depression in a community-based sample of premenopausal or early perimenopausal African American and White women. Menstrual cycle characteristics, psychosocial and health-related factors, and blood samples for assay of reproductive hormones were obtained annually. Two hundred and sixty-six women without a history of major depression at baseline constituted the cohort for the current analyses. RESULTS Over 7 years of follow-up, 42 (15.8%) women met criteria for a diagnosis of major depression. Frequent vasomotor symptoms (VMS; hot flashes and/or night sweats) (HR 2.14, p=0.03) were a significant predictor of major depression in univariate analyses. After simultaneous adjustment for multiple predictors in Cox proportional hazards analyses, frequent VMS were no longer significant; lifetime history of an anxiety disorder (HR 2.20, p=0.02) and role limitations due to physical health (HR 1.88, p=0.07) at baseline and a very stressful life event (HR 2.25, p=0.04) prior to depression onset predicted a first episode of major depression. CONCLUSIONS Both earlier (e.g. history of anxiety disorders) and more proximal factors (e.g. life stress) may be more important than VMS in contributing to a first episode of major depression during midlife.
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Scuteri A, Vuga M, Najjar SS, Mehta V, Everson-Rose SA, Sutton-Tyrrell K, Matthews K, Lakatta EG. Education eclipses ethnicity in predicting the development of the metabolic syndrome in different ethnic groups in midlife: the Study of Women's Health Across the Nation (SWAN). Diabet Med 2008; 25:1390-9. [PMID: 19046236 PMCID: PMC2607571 DOI: 10.1111/j.1464-5491.2008.02596.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
OBJECTIVE To determine the respective roles of socio-economic status (SES) and ethnicity in the risk of incident metabolic syndrome in middle-aged women. DESIGN AND PARTICIPANTS A total of 3302 pre- and peri-menopausal women, not receiving hormone therapy at baseline, took part in the Study of Women's Health Across the Nation, a multi-site, community-based, longitudinal study of the menopausal transition. The main outcome measures were to ascertain the prevalence of the metabolic syndrome and the incidence of the metabolic syndrome over 5 years of follow-up. RESULTS At baseline, the prevalence of the metabolic syndrome was 21% (n = 673). Among 2512 women without metabolic syndrome at baseline, 12.8% (n = 321) developed the metabolic syndrome during 5 years of follow-up. Both ethnicity and SES were significant univariate predictors of incident metabolic syndrome. In multivariate logistic regression models that included age at baseline, menopausal status and site, baseline smoking and alcohol consumption at follow-up visit 1, as well as baseline values of each of the components of the metabolic syndrome, only education was an independent predictor of incident metabolic syndrome. CONCLUSION Approximately 13% of peri-menopausal women developed the metabolic syndrome during the 5-year follow-up period. Education, but not ethnicity, was an independent predictor of incident metabolic syndrome risk.
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Anderson IM, Ferrier IN, Baldwin RC, Cowen PJ, Howard L, Lewis G, Matthews K, McAllister-Williams RH, Peveler RC, Scott J, Tylee A. Evidence-based guidelines for treating depressive disorders with antidepressants: a revision of the 2000 British Association for Psychopharmacology guidelines. J Psychopharmacol 2008; 22:343-96. [PMID: 18413657 DOI: 10.1177/0269881107088441] [Citation(s) in RCA: 335] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A revision of the 2000 British Association for Psychopharmacology evidence-based guidelines for treating depressive disorders with antidepressants was undertaken to incorporate new evidence and to update the recommendations where appropriate. A consensus meeting involving experts in depressive disorders and their management was held in May 2006. Key areas in treating depression were reviewed, and the strength of evidence and clinical implications were considered. The guidelines were drawn up after extensive feedback from participants and interested parties. A literature review is provided, which identifies the quality of evidence to inform the recommendations, the strength of which are based on the level of evidence. These guidelines cover the nature and detection of depressive disorders, acute treatment with antidepressant drugs, choice of drug versus alternative treatment, practical issues in prescribing and management, next-step treatment, relapse prevention, treatment of relapse, and stopping treatment.
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Welch C, Matthews K, Dugas J, Ham K, Hogstrom K. WE-C-332-04: Computed Tomography Imaging to Quantify Iodine Distribution in IUdR-Labeled DNA. Med Phys 2008. [DOI: 10.1118/1.2962718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Hawkins GJ, Sherwood RE, Barrett BM, Wallace M, Orr HJB, Matthews K, Bisht S. High-performance infrared narrow-bandpass filters for the Indian National Satellite System meteorological instrument (INSAT-3D). APPLIED OPTICS 2008; 47:2346-2356. [PMID: 18449299 DOI: 10.1364/ao.47.002346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This paper describes the design and manufacture of a set of precision cooled (210 K) narrow-bandpass filters for the infrared imager and sounder on the Indian Space Research Organisation (ISRO) INSAT-3D meteorological satellite. We discuss the basis for the choice of multilayer coating designs and materials for 21 differing filter channels, together with their temperature-dependence, thin film deposition technologies, substrate metrology, and environmental durability performance.
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Matthews K, Rhind SM, Gossner AG, Dalziel RG, Hopkins J. The effects of gene gun delivered pIL-3 adjuvant on skin pathology and cytokine expression. Vet Immunol Immunopathol 2007; 119:233-42. [PMID: 17628699 DOI: 10.1016/j.vetimm.2007.05.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2007] [Revised: 05/16/2007] [Accepted: 05/29/2007] [Indexed: 11/18/2022]
Abstract
The aim of this study was to investigate skin immunopathology following gene gun delivery of plasmid-encoding interleukin 3 (pIL-3) and hence explore the possible mechanisms of its adjuvant activity. Using the sheep as the experimental model, expressible pIL-3 was administered to the epidermis and the dermal/epidermal junction and its effects on the skin were assessed by histopathology, immunohistology and quantitative RT-PCR for a range of pro-inflammatory and immune response polarizing cytokines. Delivery of both functional and non-functional plasmids caused an acute inflammatory response with the infiltration of neutrophils and micro-abscess formation; however, the response to pIL-3 was more severe and was also associated with an early (24 h) infiltration of B cells and a later accumulation of CD172a-/CD45RA+ dendritic cells (DC). In terms of cytokine transcript expression, an early TNFalpha response was stimulated by gene gun delivery of plasmid-associated gold beads, which coincided with an immediate infiltration of neutrophils. However, only pIL-3 triggered the short-lived expression of IL-3 (peaking at 6 h) and significant long-term increases in both TNFalpha and IL-1beta. pIL-3 did not affect the expression of the immune response polarizing cytokines, IL-10 and IL-12.
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Dugas J, Oves S, Matthews K, Sajo E, Hogstrom K. SU-FF-T-235: Fluence Determination in a Polarized Synchrotron-Generated Monochromatic X-Ray Beam. Med Phys 2007. [DOI: 10.1118/1.2760896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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63
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Matthews K, Rhind SM, Gossner AG, Dalziel RG, Hopkins J. The effect of gene gun-delivered pGM-CSF on the immunopathology of the vaccinated skin. Scand J Immunol 2007; 65:298-307. [PMID: 17309785 DOI: 10.1111/j.1365-3083.2007.01902.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The aim of this study was to investigate the skin immunopathology of gene gun-delivered plasmid-encoded granulocyte-macrophage colony-stimulating factor (pGM-CSF) and hence explore the possible mechanisms of its adjuvant activity. Using sheep as the experimental model, expressible pGM-CSF was administered to the epidermis and the dermal/epidermal junction and its effects on the skin were assessed by histopathology, immunohistology and quantitative RT-PCR for a range of pro-inflammatory and immune response-polarizing cytokines. Both functional and non-functional plasmids caused an acute inflammatory response with the infiltration of neutrophils and micro-abscess formation; however, the response to pGM-CSF was more severe and was also associated with the accumulation of eosinophils, immature (CD1b(-)/CD172a(-)) dendritic cells and B cells. In terms of cytokine expression, an early TNF-alpha response was stimulated by gene gun delivery of plasmid-associated gold beads, which coincided with an immediate infiltration of neutrophils. However, only pGM-CSF triggered the short-lived expression of GM-CSF (peaking at 4 h) and significant long-term increases in both TNF-alpha and IL-1beta. pGM-CSF did not affect the expression of the immune response-polarizing cytokines, IL-10 and IL-12.
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Ahern V, Bull C, Harris J, Matthews K, Willis D. Subspecialization of radiation therapists in Australia and New Zealand. ACTA ACUST UNITED AC 2007; 51:104-5. [PMID: 17419852 DOI: 10.1111/j.1440-1673.2007.01676.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Matthews K, Bailey SL, Gossner AG, Watkins C, Dalziel RG, Hopkins J. Gene Gun-delivered pGM-CSF Adjuvant Induces Enhanced Emigration of two Dendritic Cell Subsets from the Skin. Scand J Immunol 2007; 65:221-9. [PMID: 17309776 DOI: 10.1111/j.1365-3083.2006.01892.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Two subsets of sheep afferent lymph dendritic cells (DC) are defined by the differential expression of CD172a and CD45RA. The majority (~70%) of CD172a(+) subset is CD45RA/CD11c(+)/CD207(+)/TLR4(+). The CD172a(-) DC are CD45RA(+)/CD207(-) and express low levels of CD11c and CD86. Real-time RT-PCR showed that CD172(+) DC produce IL-1beta and IL-10 and high levels of IL-18 but almost no IL-12p40; CD172a(-) DC express IL-12p40 but no IL-10 and low levels of IL-1beta and IL-18. Gene gun-delivered granulocyte-macrophage colony-stimulating factor (pGM-CSF) caused an early rise in the output of CD172a(+) DC, changes to DC phenotype and significant increases in the levels of expression cytokine transcripts. However, pGM-CSF did not affect any qualitative changes to cytokine expression, CD172a(+) DC remained IL-10(+)/IL-12p40(-) and the CD172(-) DC remained IL-10(-)/IL-12p40(+).
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Nutt DJ, Fone K, Asherson P, Bramble D, Hill P, Matthews K, Morris KA, Santosh P, Sonuga-Barke E, Taylor E, Weiss M, Young S. Evidence-based guidelines for management of attention-deficit/hyperactivity disorder in adolescents in transition to adult services and in adults: recommendations from the British Association for Psychopharmacology. J Psychopharmacol 2007; 21:10-41. [PMID: 17092962 DOI: 10.1177/0269881106073219] [Citation(s) in RCA: 185] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is an established diagnosis in children, associated with a large body of evidence on the benefits of treatment. Adolescents with ADHD are now leaving children's services often with no readily identifiable adult service to support them, which presents problems as local pharmacy regulations often preclude the prescription of stimulant drugs by general practitioners (GPs). In addition, adults with ADHD symptoms are now starting to present to primary care and psychiatry services requesting assessment and treatment. For these reasons, the British Association for Psychopharmacology (BAP) thought it timely to hold a consensus conference to review the body of evidence on childhood ADHD and the growing literature on ADHD in older age groups. Much of this initial guidance on managing ADHD in adolescents in transition and in adults is based on expert opinion derived from childhood evidence. We hope that, by the time these guidelines are updated, much evidence will be available to address the many directions for future research that are detailed here.
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Tsai TH, Matthews K, Dalley JW. Determination of Glutamate in Rat Brain Microdialysates by Microbore Liquid Chromatography with Electrochemical Detection. J LIQ CHROMATOGR R T 2006. [DOI: 10.1080/10826079708006579] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Smith B, Matthews K, Hill W, Lackie A, Wang WH, Cherry M. TH-D-330A-02: An Electronically-Collimated Gamma-Ray Detector for Intraoperative Localization of Radiation Sources. Med Phys 2006. [DOI: 10.1118/1.2241893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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69
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Lackie A, Matthews K, Smith B, Hill W, Wang WH, Cherry M. SU-CC-ValA-03: A Directional Algorithm for An Electronically-Collimated Gamma-Ray Detector for Intraoperative Localization of Radiation Sources. Med Phys 2006. [DOI: 10.1118/1.2240121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Dierking I, Biddulph G, Matthews K. Electromigration of microspheres in nematic liquid crystals. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2006; 73:011702. [PMID: 16486164 DOI: 10.1103/physreve.73.011702] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2005] [Revised: 10/07/2005] [Indexed: 05/06/2023]
Abstract
Application of an electric field to microspheres, dispersed in a nematic liquid crystal host material, causes particle translation along the direction of the average long molecular liquid crystal axis, i.e., the director. We have determined the stability regime of linear particle displacement in the parameter space of electric field amplitude and frequency for various applied electric wave forms and demonstrate a linear relationship between microsphere velocity and applied electric field amplitude. For increasing frequency the particle velocity exhibits a maximum before motion slowly vanishes. Addition of a small amount of an ionic dopant is shown to largely increase the stability region of linear microsphere motion, with particle velocities increasing until saturation is observed for increasing ion dopant concentration. It is presumed that the particle velocity is related to the surface charges adsorbed on the dispersed particles. Also the dynamics of occasionally observed two- and three-particle clusters is discussed.
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Kelly L, Matthews K. SU-FF-I-46: Performance Evaluation and Comparison of Two Cadmium Zinc Telluride Gamma Cameras. Med Phys 2005. [DOI: 10.1118/1.1997526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Verma VK, Hollenberg SM, Dumasius A, Matthews K, Sutton-Tyrrell K, Powell L. Determinants of Coronary Calcification and Aortic Calcification in Perimenopausal Women. Chest 2004. [DOI: 10.1378/chest.126.4_meetingabstracts.790s-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Sivarajasingam V, Shepherd JP, Matthews K. Effect of urban closed circuit television on assault injury and violence detection. Inj Prev 2004; 9:312-6. [PMID: 14693891 PMCID: PMC1731032 DOI: 10.1136/ip.9.4.312] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To evaluate the effect of closed circuit television (CCTV) surveillance on levels of assault injury and violence detection. DESIGN Intervention versus control study design. SETTING Five town/cities with CCTV surveillance and five, matched control centres without CCTV surveillance in England. INTERVENTION CCTV installation and surveillance. METHODS Assault related emergency department attendances and violent offences recorded by the police in CCTV and control centres in the four years, 1995-99, two years before and two years after CCTV installation, were compared. RESULTS Assault related emergency department attendances decreased in intervention centres (3% decrease, ratio 0.96; 95% confidence interval (CI) 0.93 to 0.99) and increased in control centres (11% increase, ratio 1.11; 95% CI 1.08 to 1.14). Overall, changes in emergency department assault attendance in CCTV and control centres were significantly different (t test, p<0.05). Police recorded violence increased in CCTV (11% increase, ratio 1.16; 95% CI 1.08 to 1.24) and control centres (5% increase, ratio 1.06; 95% CI 0.99 to 1.13). Overall, changes in police recording in CCTV and control centres were not significantly different (t test, p>0.05). In CCTV centres, decreases in assault related emergency department attendances and increases in police violence detection were not uniform. CONCLUSION CCTV surveillance was associated with increased police detection of violence and reductions in injury or severity of injury. CCTV centre variation deserves further study.
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Grondin Y, Matthews K, McEntee M, Rainford L, Casey M, Tonra M, Al-Qattan E, McCrudden T, Foley M, Brennan PC. Dose-reducing strategies in combination offers substantial potential benefits to females requiring X-ray examination. RADIATION PROTECTION DOSIMETRY 2004; 108:123-132. [PMID: 14978292 DOI: 10.1093/rpd/nch015] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This work, using an adult anthropomorphic phantom, aimed to establish an optimised technique for ladies of child-bearing age undergoing antero-posterior (AP) pelvis and AP and lateral lumbar spine examinations. Phase one of the work involved introducing the following dose-reducing measures individually: increased kVp, increased focus-film distances, a carbon fibre cassette, a faster film/screen combination. The second phase established an optimised technique based on a combination of the parameters listed above. Radiation dose was measured using thermoluminescent dosimeters and image quality was evaluated using anatomical criteria. All dose-reducing methods were compared with a standard technique, currently being used in a Dublin hospital. The results demonstrated that the optimised procedure reduced effective dose by 77, 62 and 66% for AP pelvis and AP and lateral lumbar spine respectively (p < 0.05) compared with the standard technique, with no significant changes in image quality. Dose-reducing measures used in combination offer substantial potential for optimisation of radiological procedures.
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Mitchell LM, Silveira M, Mylne MJA, Matthews K, Dingwall WS. Seasonal differences in lamb birthweight do not arise from inherent differences in the oocyte and/or early embryo. Reprod Fertil Dev 2003; 14:207-13. [PMID: 12219943 DOI: 10.1071/rd01054] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The aim of this study was to determine whether previously observed seasonal differences in conceptus development in ewes are attributable to inherent differences in the oocyte and/or early embryo. Day 6 embryos were recovered from 50 ewes subjected to a standard oestrus synchronization, superovulation and laparoscopic artificial insemination protocol during October (peak breeding season) and April (transition to anoestrus). During the following October, 40 grade 1 and 2 embryos from each month, which had been cryopreserved at the late morula or unexpanded blastocyst stage, were thawed and transferred in singleton to synchronous recipients. Resulting pregnancies were monitored to term. For ewes receiving October- and April-produced embryos, overall mean +/- SEM liveweight at the time of embryo transfer was 72 +/- 0.7 kg, body condition score was 3.1 +/- 0.04 units, and the number of corpora lutea on the ovaries was 2.7 +/- 0.11 per ewe. Thirty-one and 27 ewes, respectively, became pregnant and their gestation lengths were 147 +/- 0.2 and 147 +/- 0.3 days. There was no effect of month of embryo production on peripheral ovine pregnancy-associated glycoprotein concentrations during pregnancy or on fetal and placental characteristics at term, but, for each month, male lambs were heavier than females and were associated with larger placentae. Lamb birthweight was positively correlated with placental weight (r2 = 0.474, P<0.001) and the total weight of cotyledonary tissue (r2 = 0.429, P<0.001), but not to the number of cotyledons. Results demonstrate close relationships between fetal and placental weights at term, and that seasonal effects on conceptus development in ewes do not arise from inherent differences in the oocyte and/or early embryo.
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Mitchell LM, Dingwall WS, Mylne MJA, Hunton J, Matthews K, Gebbie FE, McCallum GJ, McEvoy TG. Season affects characteristics of the pre-ovulatory LH surge and embryo viability in superovulated ewes. Anim Reprod Sci 2002; 74:163-74. [PMID: 12417118 DOI: 10.1016/s0378-4320(02)00190-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The aim of this study was to determine whether there are seasonal shifts in ovulatory response, and in the viability of ova recovered from superovulated ewes. Fifty mature ewes underwent a standard oestrous synchronisation (CIDR), superovulation (oFSH) and artificial insemination procedure during October (peak breeding season) and April (transition to anoestrus). In each month peripheral LH and progesterone concentrations were measured around the time of ovulation and embryos were recovered, graded and cryopreserved on day 6 after insemination. During the subsequent breeding season, grade 1 and 2 morulae and unexpanded blastocysts were thawed and transferred singly to synchronous recipients (October, n = 40; April, n = 40) or cultured in vitro for 18-20 h (October, n = 107; April, n = 98). Following culture, viable embryos were stained to count cell nuclei or assayed to measure their capacity for glucose metabolism ([3H]glucose) and protein synthesis ([35S]methionine). Peak LH concentrations were higher in October than in April (38.2 +/- 3.26 ng ml(-1) versus 25.7 +/- 1.99 ng ml(-1), respectively; P < 0.01) and the pre-ovulatory LH surge was advanced by approximately 3 h (P < 0.05). Progesterone concentrations at CIDR withdrawal were lower in October than in April (3.1 +/- 0.16 ng ml(-1) versus 4.3 +/- 0.19 ng ml(-1), respectively; P < 0.001) but were not different at embryo recovery. Season did not affect the numbers of corpora lutea per ewe or the numbers of ova recovered but the proportion of recovered ova that was unfertilised/degenerate was lower in October than in April (0.43 versus 0.58, respectively; P < 0.001). For embryos containing more than 16 cells, there was no effect of season on the median stage of development or morphological grade. The proportions of October and April embryos that established pregnancy following transfer to recipient ewes were 0.78 and 0.70 (not significantly different), and that were viable after in vitro culture were 0.66 and 0.37 (P < 0.05), respectively. Season did not affect the number of nuclei per viable embryo or the capacity for protein synthesis but the glucose uptake of October embryos was approximately double that of April embryos (3163+/-293.4 dpm versus 1550+/-358.9 dpm, respectively; P < 0.05). Results indicate that during the late compared to peak breeding season, there is an increased incidence of fertilisation failure as a possible consequence of seasonal shifts in LH secretion and (or) associated effects on follicular function. Frozen-thawed embryos produced at contrasting stages of the breeding season are equally viable in vivo but those produced during the late, as opposed to the peak breeding season have lower viability following in vitro culture.
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Castilla RC, Bromberger J, Perel JM, Matthews K. #40-S association of depression with increases of plasma fibrinogen concentrations in midlife women. Ann Epidemiol 2002. [DOI: 10.1016/s1047-2797(02)00328-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Wright GL, Wang S, Fultz ME, Arif I, Matthews K, Chertow BS. Effect of vitamin A deficiency on cardiovascular function in the rat. Can J Physiol Pharmacol 2002; 80:1-7. [PMID: 11911220 DOI: 10.1139/y01-093] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Selected parameters of cardiovascular function were evaluated in vitamin A-deficient rats at 70 days of age. Resting heart rate was increased by an average of 100 bpm (21.4+/-2.7%), whereas resting systolic blood pressure was normal in vitamin A-deficient animals. The maximal contractile force developed per milligram weight of tissue by aortic rings excised from vitamin A-deficient animals was reduced in response to high potassium (-25.0+/-8.7%) and phorbol 12,13-dibutyrate (-36.8+/-8.4%) but was only slightly reduced in response to norepinephrine (-17.8+/-11.1%). Intimal rubbing to remove the endothelium had no effect on the loss in contractile responsiveness, and the relaxant response to acetylcholine was similar between control and vitamin A-deficient tissue groups. This suggests that the decrease in contractility of vascular smooth muscle from the vitamin A-deficient rats did not involve altered release of endothelium-derived vasoactive factors. Western blot analysis suggested a reduction in the protein levels of several differentiation markers including alpha-actin (-22%), calponin (-37%), desmin (-37%), and vinculin (-40%), whereas the level of PKCalpha was unchanged from control values. Our findings indicate a significant decrease in contractile responsiveness of aortic smooth muscle of the vitamin A-deficient rat that may be associated with a down regulation in the expression of contractile-related proteins.
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Curran S, Matthews K. Response to Yaryura-Tobias et al (2000) negative outcome after neurosurgery for refractory obsessive-compulsive spectrum disorder, World J Biol Psychiatry 1: 197-203. World J Biol Psychiatry 2001; 2:107. [PMID: 12587194 DOI: 10.3109/15622970109027502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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82
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Curran S, Matthews K. "The psychiatrist will be with you in a day or two". Unnecessary delays in assessing the mentally ill in police custody in Scotland. Scott Med J 2001; 46:37. [PMID: 11394334 DOI: 10.1177/003693300104600202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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83
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Matthews K, Dalley JW, Matthews C, Tsai TH, Robbins TW. Periodic maternal separation of neonatal rats produces region- and gender-specific effects on biogenic amine content in postmortem adult brain. Synapse 2001; 40:1-10. [PMID: 11170216 DOI: 10.1002/1098-2396(200104)40:1<1::aid-syn1020>3.0.co;2-e] [Citation(s) in RCA: 147] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Early environment exerts profound effects on mammalian behavioral and neural development. The aim of this study was to describe changes in adult neurochemistry in the rat following repeated neonatal maternal separation (RMS) during the preweaning period, a procedure known to induce enduring behavioral effects. Following RMS, rats show an attenuated locomotor response to novelty, to D-amphetamine, and attenuated behavioral responses for conditioned incentives as adults. These behavioral effects are broadly opposite in direction to those found following postweaning isolation rearing. Isolation rearing-induced behavioral changes are associated with profound changes in central monoamine function. Following RMS, adult rats had increased tissue levels of dopamine in both dorsal and ventral striatum. The turnover of dopamine, as determined by the ratio of DOPAC to dopamine, was decreased in the mPFC of RMS subjects. Serotonin levels were reduced in dorsal hippocampus of RMS rats of both sexes and in the mPFC of male RMS rats. Noradrenaline levels were increased in the dorsal hippocampus in female, but not in male, RMS rats. These data provide evidence that, in addition to the adult behavioral consequences, RMS leads to profound, region-, and gender-specific changes in brain monoamine content. The developmental specificity of these results is discussed with respect to their possible role in altered behavioral development and psychopathology.
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MESH Headings
- Animals
- Animals, Newborn/anatomy & histology
- Animals, Newborn/metabolism
- Animals, Newborn/psychology
- Anxiety, Separation/metabolism
- Anxiety, Separation/physiopathology
- Behavior, Animal/physiology
- Biogenic Monoamines/metabolism
- Brain/cytology
- Brain/growth & development
- Brain/metabolism
- Dopamine/metabolism
- Environment, Controlled
- Female
- Male
- Maternal Deprivation
- Norepinephrine/metabolism
- Rats
- Rats, Inbred Strains
- Serotonin/metabolism
- Sex Factors
- Stress, Psychological/metabolism
- Stress, Psychological/physiopathology
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Eljamel MS, Forster A, Tulley M, Matthews K. Staged functional neurosurgery using image fusion: electronic atlas and microelectrode recording at Dundee. Stereotact Funct Neurosurg 2000; 73:140-2. [PMID: 10853121 DOI: 10.1159/000029774] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The unforgiving nature of the thalamus, the globus pallidus and the subthalamic nucleus necessitates precise localization of functional targets. This requires the total attention of both the patient and the surgeon. To maximize the concentration of the patient and provide the most accurate localization, we performed staged stereotactic functional procedures. The first stage was performed under general anesthesia to abolish any head movement. We fused CT and MRI images and correlated the fused images with a digitized Talairach brain atlas. We calculated the target coordinates and fixed a modified Bennett Sphere to the skull with the central hole defining the trajectory to the target. The surrounding 12 holes gave parallel trajectories to targets surrounding the anatomical target at 2-mm intervals. The second stage was performed at least a week later under local anesthesia. Microelectrode recording using three simultaneous channels was used to refine the target. Once the microelectrode recordings and macrostimulation confirmed the desired target, a lesion was created or an Activa neurostimulator was inserted. Our early results using this technique in 28 procedures (in 19 patients) indicate a good outcome in 86% and a technical failure in 1 patient.
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85
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Epel ES, McEwen B, Seeman T, Matthews K, Castellazzo G, Brownell KD, Bell J, Ickovics JR. Stress and body shape: stress-induced cortisol secretion is consistently greater among women with central fat. Psychosom Med 2000; 62:623-32. [PMID: 11020091 DOI: 10.1097/00006842-200009000-00005] [Citation(s) in RCA: 267] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Excessive central fat puts one at greater risk of disease. In animal studies, stress-induced cortisol secretion has been shown to increase central fat. The objective of this study was to assess whether women with central fat distribution (as indicated by a high waist-to-hip ratio [WHR]), across a range of body mass indexes, display consistently heightened cortisol reactivity to repeated laboratory stressors. METHODS Fifty-nine healthy premenopausal women, 30 with a high WHR and 29 with a low WHR, were exposed to consecutive laboratory sessions over 4 days (three stress sessions and one rest session). During these sessions, cortisol and psychological responses were assessed. RESULTS Women with a high WHR evaluated the laboratory challenges as more threatening, performed more poorly on them, and reported more chronic stress. These women secreted significantly more cortisol during the first stress session than women with a low WHR. Furthermore, lean women with a high WHR lacked habituation to stress in that they continued to secrete significantly more cortisol in response to now familiar challenges (days 2 and 3) than lean women with a low WHR. CONCLUSIONS Central fat distribution is related to greater psychological vulnerability to stress and cortisol reactivity. This may be especially true among lean women, who did not habituate to repeated stress. The current cross-sectional findings support the hypothesis that stress-induced cortisol secretion may contribute to central fat and demonstrate a link between psychological stress and risk for disease.
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Walley RL, Wilson JB, Crane JM, Matthews K, Sawyer E, Hutchens D. A double-blind placebo controlled randomised trial of misoprostol and oxytocin in the management of the third stage of labour. BJOG 2000; 107:1111-5. [PMID: 11002954 DOI: 10.1111/j.1471-0528.2000.tb11109.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To compare oral misoprostol 400 microg with intramuscular oxytocin 10 IU in the routine management of the third stage. DESIGN Double-blind placebo controlled trial. SETTING Main referral hospital and its associated polyclinics in Accra, Ghana. POPULATION Four hundred and one low risk women, in the second stage of labour with anticipated vaginal delivery, who entered labour spontaneously. METHODS After delivery of the anterior shoulder of the baby, the women were randomised to receive either: 1. misoprostol 400 microg powder in water orally and 1 mL normal saline intramuscular injection (placebo); or 2. powdered cellulose in water orally (placebo) and 1 mL oxytocin 10 IU intramuscular injection. MAIN OUTCOME MEASURES Change in haemoglobin concentration from before delivery to 12 hours postpartum. Secondary outcomes included need for additional oxytocics, blood loss > 500 mL and > 1,000 mL, operative intervention for postpartum haemorrhage, and side effects, including nausea, vomiting, diarrhoea, shivering and elevated temperature. RESULTS Demographic characteristics were similar. There was no significant difference in change in haemoglobin concentration between the two groups (0.60 g/dL for misoprostol and 0.55 g/dL for oxytocin; relative difference 9.6%; 95% CI 20.5-39.6%; P = 0.54). There were no significant differences in secondary outcomes with the exception of shivering, which occurred more frequently in the misoprostol group (22.2% vs 5.7%; relative risk 4.73; 95% CI 2.31-9.68; P < 0.0001). CONCLUSIONS In low risk women oral misoprostol appears to be as effective in minimising blood loss in the third stage of labour as intramuscular oxytocin. Shivering was noted more frequently with misoprostol use, but no other side effects were noted. Misoprostol has great potential for use in the third stage of labour especially in developing countries.
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Doerig C, Chakrabarti D, Kappes B, Matthews K. The cell cycle in protozoan parasites. PROGRESS IN CELL CYCLE RESEARCH 2000; 4:163-83. [PMID: 10740824 DOI: 10.1007/978-1-4615-4253-7_15] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Research into cell cycle control in protozoan parasites, which are responsible for major public health problems in the developing world, has been hampered by the difficulties in performing classical genetic analysis with these organisms. Nevertheless, in a large part thanks to the data gathered in other eukaryotic systems and to the acquisition of the sequences of parasite genes homologous to cell cycle regulators, many molecular tools required for an in-depth study of the cell cycle in protozoan parasites have been collected over the past few years. Despite the considerable phylogenetic divergence between these organisms and other eukaryotes, and notwithstanding important specificities such as the apparent lack of checkpoints during cell cycle progression, available data indicate that the major families of cell cycle regulators appear to operate in protozoan parasites. Functional studies are now needed to define the precise role of these regulators in the life cycle of the parasites, and to possibly validate cell cycle control elements as potential targets for chemotherapy.
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Heckert KA, Matthews K. Toward totally smokefree schools and beyond: the Crown Public Health Smokefree Schools Grant Program. HEALTH EDUCATION & BEHAVIOR 2000; 27:328-38. [PMID: 10834806 DOI: 10.1177/109019810002700307] [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: 11/16/2022]
Abstract
A three-year small grants scheme in Canterbury and the West Coast, New Zealand aims to influence the health promoting climate of schools by adopting totally smokefree policies. The Smokefree Environments Act of 1990 established the legal imperative for school policies. The principles of the Treaty of Waitangi and the strategies of the Ottawa Charter provide the programmatic and evaluation framework. Evaluation indicators include the organizational and policy context, status of school smoking policies, reasons for participation, stakeholder involvement, the value of additional funding, and the extent of media coverage. Partnerships among local smokefree partners, schools and whanau/communities, and between the health and education sectors are a priority. Interim findings indicate the Crown Public Health Smokefree Schools Grant program has positively influenced policy development toward totally smokefree schools. Based on these results and the changing environment, the smokefree efforts are being integrated into the broader context of health promoting schools.
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Devlin G, Matthews K, McCracken G, Stuart S, Jensen J, Conaglen J, Bass J. An ovine model of chronic stable heart failure. J Card Fail 2000; 6:140-3. [PMID: 10908088 DOI: 10.1016/s1071-9164(00)90016-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND Chronic stable large animal models of heart failure are difficult to establish. We report an ovine model of chronic stable heart failure achieved by a technique of repetitive myocardial infarctions (one of the most common causes of cardiac failure) with catheter-based techniques. METHODS AND RESULTS Ejection fraction (EF) was assessed by echocardiography. A perfusion catheter was positioned in either the left anterior descending or circumflex artery by using standard angioplasty techniques. Myocardial infarction was induced by a Gelfoam embolism via this catheter and was confirmed by electrocardiographic (ECG) changes and new segmental abnormalities. The procedure was repeated at 2 weekly intervals until the EF was less than 40%. Target EF was achieved in 15 animals, with a mean of 3.4 embolizations (range 2 to 8). Baseline EF was 68%, with a mean final EF of 33%. This resulted in a 54% reduction in EF (range 44% to 68%) from baseline values. Two animals developed late symptomatic heart failure and died, whereas EF was stable at 3-month follow-up echocardiography in the remaining animals with no significant spontaneous improvement. CONCLUSION Chronic stable heart failure can be established in sheep with catheter-based skills and a microembolization technique that causes repetitive myocardial infarctions.
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Iribarren C, Sidney S, Bild DE, Liu K, Markovitz JH, Roseman JM, Matthews K. Association of hostility with coronary artery calcification in young adults: the CARDIA study. Coronary Artery Risk Development in Young Adults. JAMA 2000; 283:2546-51. [PMID: 10815118 DOI: 10.1001/jama.283.19.2546] [Citation(s) in RCA: 139] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Psychosocial factors, including personality and character traits, may play a role in the development and expression of coronary artery disease. OBJECTIVE To evaluate whether hostility, a previously reported predictor of clinical coronary artery disease, is associated with coronary calcification, which is a marker of subclinical atherosclerosis. DESIGN Prospective cohort study. SETTING AND PARTICIPANTS Volunteer subsample from Chicago, Ill, and Oakland, Calif, consisting of 374 white and black men and women, aged 18 to 30 years at baseline, who participated in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Cook-Medley hostility assessment data were collected at baseline from 1985 to 1986 and at year 5 examinations from 1990 to 1992. After the 10-year examinations in the 1995-1996 year, electron-beam computed tomographic scans were performed. MAIN OUTCOME MEASURES Presence of any detectable coronary artery calcification (coronary calcium score >0), and coronary artery calcium scores of 20 or higher. RESULTS In logistic regression analysis adjusting for age, sex, race, and field center comparing those with hostility scores above and below the median of the distribution of the present sample, the odds ratio of having any coronary calcification was 2.57 (95% confidence interval, 1.31-5.22), and the odds ratio of having a calcium score of 20 or higher was 9.56 (95% confidence interval, 2.29-65.9) for calcium scores of 20 or higher. The associations with any coronary artery calcification persisted after adjusting for demographic, lifestyle, and physiological variables. Results using a cynical distrust subscale were somewhat weaker than for those using the global hostility score. Power was inadequate to perform sex- or race-specific analyses. CONCLUSION These results suggest that a high hostility level may predispose young adults to coronary artery calcification. JAMA. 2000;283:2546-2551
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Tasker M, Wilson J, Sarkar M, Hendriks E, Matthews K. A novel selection regime for differentiation defects demonstrates an essential role for the stumpy form in the life cycle of the African trypanosome. Mol Biol Cell 2000; 11:1905-17. [PMID: 10793160 PMCID: PMC14892 DOI: 10.1091/mbc.11.5.1905] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
A novel selection scheme has been developed to isolate bloodstream forms of Trypanosoma brucei, which are defective in their ability to differentiate to the procyclic stage. Detailed characterization of one selected cell line (defective in differentiation clone 1 [DiD-1]) has demonstrated that these cells are indistinguishable from the wild-type population in terms of their morphology, cell cycle progression, and biochemical characteristics but are defective in their ability to initiate differentiation to the procyclic form. Although a small proportion of DiD-1 cells remain able to transform, deletion of the genes for glycophosphatidyl inositol-phospholipase C demonstrated that this enzyme was not responsible for this inefficient differentiation. However, the attenuated growth of the Delta-glycophosphatidyl inositol-phospholipase C DiD-1 cells in mice permitted the expression of stumpy characteristics in this previously monomorphic cell line, and concomitantly their ability to differentiate efficiently was restored. Our results indicate that monomorphic cells retain expression of a characteristic of the stumpy form essential for differentiation, and that this is reduced in the defective cells. This approach provides a new route to dissection of the cytological and molecular basis of life cycle progression in the African trypanosome.
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Eikenberry SS, Matthews K, Muno M, Blanco PR, Morgan EH, Remillard RA. Faint Infrared Flares from the Microquasar GRS 1915+105. THE ASTROPHYSICAL JOURNAL 2000; 532:L33-L36. [PMID: 10702126 DOI: 10.1086/312559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We present simultaneous infrared and X-ray observations of the Galactic microquasar GRS 1915+105 using the Palomar 5 m telescope and Rossi X-Ray Timing Explorer on 1998 July 10 UT. Over the course of 5 hr, we observed six faint infrared (IR) flares with peak amplitudes of approximately 0.3-0.6 mJy and durations of approximately 500-600 s. These flares are associated with X-ray soft-dip/soft-flare cycles, as opposed to the brighter IR flares associated with X-ray hard-dip/soft-flare cycles seen in 1997 August by Eikenberry et al. Interestingly, the IR flares begin before the X-ray oscillations, implying an "outside-in" origin of the IR/X-ray cycle. We also show that the quasi-steady IR excess in 1997 August is due to the pileup of similar faint flares. We discuss the implications of this flaring behavior for understanding jet formation in microquasars.
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Hall M, Bromberger J, Matthews K. Socioeconomic status as a correlate of sleep in African-American and Caucasian women. Ann N Y Acad Sci 2000; 896:427-30. [PMID: 10681942 DOI: 10.1111/j.1749-6632.1999.tb08161.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Berglund L, Oliver EH, Fontanez N, Holleran S, Matthews K, Roheim PS, Ginsberg HN, Ramakrishnan R, Lefevre M. HDL-subpopulation patterns in response to reductions in dietary total and saturated fat intakes in healthy subjects. Am J Clin Nutr 1999; 70:992-1000. [PMID: 10584043 DOI: 10.1093/ajcn/70.6.992] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Little information is available about HDL subpopulations during dietary changes. OBJECTIVE The objective was to investigate the effect of reductions in total and saturated fat intakes on HDL subpopulations. DESIGN Multiracial, young and elderly men and women (n = 103) participating in the double-blind, randomized DELTA (Dietary Effects on Lipoproteins and Thrombogenic Activities) Study consumed 3 different diets, each for 8 wk: an average American diet (AAD: 34.3% total fat,15.0% saturated fat), the American Heart Association Step I diet (28.6% total fat, 9.0% saturated fat), and a diet low in saturated fat (25.3% total fat, 6.1% saturated fat). RESULTS HDL(2)-cholesterol concentrations, by differential precipitation, decreased (P < 0.001) in a stepwise fashion after the reduction of total and saturated fat: 0.58 +/- 0.21, 0.53 +/- 0.19, and 0.48 +/- 0.18 mmol/L with the AAD, Step I, and low-fat diets, respectively. HDL(3) cholesterol decreased (P < 0.01) less: 0.76 +/- 0.13, 0.73 +/- 0.12, and 0.72 +/- 0.11 mmol/L with the AAD, Step I, and low-fat diets, respectively. As measured by nondenaturing gradient gel electrophoresis, the larger-size HDL(2b) subpopulation decreased with the reduction in dietary fat, and a corresponding relative increase was seen for the smaller-sized HDL(3a, 3b), and (3c) subpopulations (P < 0.01). HDL(2)-cholesterol concentrations correlated negatively with serum triacylglycerol concentrations on all 3 diets: r = -0.46, -0.37, and -0.45 with the AAD, Step I, and low-fat diets, respectively (P < 0.0001). A similar negative correlation was seen for HDL(2b), whereas HDL(3a, 3b), and (3c) correlated positively with triacylglycerol concentrations. Diet-induced changes in serum triacylglycerol were negatively correlated with changes in HDL(2) and HDL(2b) cholesterol. CONCLUSIONS A reduction in dietary total and saturated fat decreased both large (HDL(2) and HDL(2b)) and small, dense HDL subpopulations, although decreases in HDL(2) and HDL(2b) were most pronounced.
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95
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Soifer BT, Matthews K, Kiger JR, Armus L. Near-Infrared Spectra of Ultraluminous Infrared Galaxies. THE ASTROPHYSICAL JOURNAL 1999; 525:L85-L88. [PMID: 10525460 DOI: 10.1086/312350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Near-infrared spectra with a resolution of lambda&solm0;Deltalambda approximately 1100 in the rest-wavelength range of 1.8-2.2 µm have been obtained for a complete sample of 33 ultraluminous infrared galaxies (ULIRGs). Of the 33 objects observed, two show evidence of a central active galactic nucleus (AGN) through either a broad Paschen-alpha line or emission in the 1.963 µm fine structure of [Si vi]. In the median spectrum of the remaining 31 objects, the lines present are recombination lines of hydrogen and neutral helium, vibration-rotation lines of H2, and [Fe ii]. There is no indication of AGN activity in the median spectrum, either through broad atomic recombination lines or through high ionization lines. No trends in luminosity are apparent when subsets of the 31 non-AGN ULIRGs are binned by luminosity and median-combined. When secondary nuclei exist in ULIRGs, they typically have spectra very much like those seen in the primary nuclei.
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Rogers RD, Blackshaw AJ, Middleton HC, Matthews K, Hawtin K, Crowley C, Hopwood A, Wallace C, Deakin JF, Sahakian BJ, Robbins TW. Tryptophan depletion impairs stimulus-reward learning while methylphenidate disrupts attentional control in healthy young adults: implications for the monoaminergic basis of impulsive behaviour. Psychopharmacology (Berl) 1999; 146:482-91. [PMID: 10550499 DOI: 10.1007/pl00005494] [Citation(s) in RCA: 218] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
RATIONALE Altered serotonergic and dopaminergic function have been widely implicated in behavioural disorders associated with impulsivity and risk-taking. However, little research has addressed the specific cognitive consequences of changed monoaminergic function that might contribute to the production of impulsive behaviour. OBJECTIVES AND METHODS We compared the effects of rapid plasma tryptophan depletion, acute doses of the mixed indirect catecholamine agonist, methylphenidate (40 mg), and acute doses of the alpha(1)/alpha(2 )agonist, clonidine (1.5 microg/kg), on aspects of visual discrimination learning involving either acquisition of altered stimulus-reward associations (i.e. updating the affective valence of exteroceptive stimuli) or the control of attention towards relevant as opposed to irrelevant stimulus dimensions. RESULTS Relative to subjects who received placebo, subjects with reduced tryptophan exhibited a deficit in the ability to learn changed stimulus-reward associations, but were still able to shift an acquired attentional set away from a now-irrelevant stimulus dimension towards a newly relevant dimension. By contrast, subjects who received methylphenidate were able to learn effectively about changing stimulus-reward associations, but showed an enhanced ability to shift an attentional bias, in combination with slowed response times. Subjects who received clonidine showed neither of these changes. CONCLUSIONS These results suggest that reduction in central serotonin leads to altered neuromodulation of the cortical and subcortical regions (e.g. orbitofrontal cortex, striatum and anterior temporal structures) that mediate important aspects of associative learning whereby exteroceptive stimuli acquire altered incentive motivational value. On the other hand, facilitation of catecholamine neurotransmitters may disrupt the allocation of attention between relevant and irrelevant features of the environment, perhaps through altered modulation of the dorsolateral prefrontal cortex. The implications of these results for understanding the differential neuromodulation of cognitive functions are discussed.
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Matthews K, Cauley J, Yaffe K, Zmuda JM. Estrogen replacement therapy and cognitive decline in older community women. J Am Geriatr Soc 1999; 47:518-23. [PMID: 10323642 DOI: 10.1111/j.1532-5415.1999.tb02563.x] [Citation(s) in RCA: 154] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND The purpose of this study was to evaluate the cross-sectional and longitudinal association of oral estrogen replacement therapy (ERT) and cognitive function in an older, nondemented sample of women. METHODS In a prospective cohort of 9651 white women aged 65 years and older enrolled in the Study of Osteoporotic Fractures, a modified Mini-Mental Status Exam (mMMSE), and digit symbol substitution and Trails B tests were administered twice, 4 to 6 years apart. History and current use of oral ERT was documented. Age, educational attainment, and activity limitations were the primary covariates in the analyses; in addition, stroke and depression scores were adjusted in subsets of women with available data. RESULTS Current and past users of ERT had better initial scores on the mMMSE than did never users, P < .05 and .001, respectively, with better scores for current estrogen hormone users being most apparent among the older and less educated women. The percentages of women scoring < or = 23 of a possible 26 on the mMMSE were 14.3 for current users, 14.5 for past users, and 20.5 for never users, P < .001. However, only past users exhibited smaller declines upon retesting in mMMSE and Trails B performance, P < .05, than did never users. Educational attainment predicted both initial test scores and change scores and was, next to age, the most powerful predictor of cognitive function. CONCLUSIONS Current oral ERT does not protect against age-related declines in cognitive function in older nondemented women, whereas formal education does protect, even though it had been completed many years earlier. The influence of education in late-life on cognitive function should be tested.
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Denise H, Matthews K, Lindergård G, Croft S, Barrett MP. Trypanosomiasis and leishmaniasis: between the idea and the reality of control. PARASITOLOGY TODAY (PERSONAL ED.) 1999; 15:43-5. [PMID: 10234181 DOI: 10.1016/s0169-4758(98)01374-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Matthews K, Robbins TW, Everitt BJ, Caine SB. Repeated neonatal maternal separation alters intravenous cocaine self-administration in adult rats. Psychopharmacology (Berl) 1999; 141:123-34. [PMID: 9952036 DOI: 10.1007/s002130050816] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Behavioural responses to psychostimulant drugs can be profoundly affected by early environmental influences. The aim of this study was to describe the effects of repeated brief separations of rat pups from their dams during the early neonatal period on cocaine self-administration behaviour as adults. Lister hooded rats exposed to a repeated maternal separation procedure (REMS) showed altered acquisition and maintenance of cocaine self-administration as adults, the effects being dose and gender-dependent. Overall, the patterns of acquisition of self-administration across three doses of cocaine (0.05, 0.08 and 0.5 mg/injection) suggested a rightward shift in the acquisition dose-effect functions for the REMS animals relative to control animals. At 0.05 mg/injection, there was a retarded acquisition of cocaine self-administration in male and female neonatally separated rats. At 0.08 mg/injection there was a facilitated acquisition in female neonatally separated subjects. After establishment of stable self-administration of the training dose, in the same cohort of subjects, rightward and downward shifts in the cocaine self-administration dose-effect functions were determined for female and male REMS subjects, respectively, relative to their controls. The dose-effect function for both female groups was shifted to the left of that of the respective male groups, although the lighter body weights of the females meant that they administered a higher unit dose per unit body weight than the males. Whereas male REMS subjects tended to self-administer less cocaine than the controls at the dose eliciting maximal responding (0.03 mg/injection) and to make fewer lever responses overall at each dose tested, female REMS subjects self-administered significantly more cocaine than their respective controls at a dose of 0.03 mg/injection. There was no differential sensitivity to the rate-altering effects of the selective dopamine D2 receptor antagonist, eticlopride, or to the selective dopamine D1 receptor antagonist, SCH 23390. These data provide further evidence that altered early environment affects drug-taking behaviour in a developmentally specific and gender-specific manner, with the effects of neonatal separation contrasting with previously published data on the effects of post-weaning isolation rearing.
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Matthews K, Webber K, McKim E, Banoub-Baddour S, Laryea M. Maternal infant-feeding decisions: reasons and influences. Can J Nurs Res 1998; 30:177-98. [PMID: 9807295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
The purpose of this prospective longitudinal study was to determine the reasons for and influences on mothers' infant-feeding decisions over the 6 months post-birth. The breastfeeding initiation rate of 41.7% had declined to 11.4% at 6 months. The major reasons for not choosing breastfeeding were embarrassment and discomfort with the idea. Younger, less-educated mothers with lower incomes were less likely to start breastfeeding, more likely to discontinue breastfeeding early, and more likely to feed their babies cheaper evaporated milks. Mothers gave up breastfeeding early because it was too difficult or because they were returning to work. Reasons given by both breastfeeding and bottle-feeding mothers for switching milks were that the baby was "not satisfied" on the milk or that it was "not agreeing with" the baby. Generally, the social network, rather then health professionals, had greater influence on mothers' decisions.
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