40 results on '"Collins, R."'
Search Results
2. Virtual Transcatheter Interventions for Peripheral Pulmonary Artery Stenosis in Williams and Alagille Syndromes.
- Author
-
Lan, Ingrid S., Weiguang Yang, Feinstein, Jeffrey A., Kreutzer, Jacqueline, Collins II, R. Thomas, Ma, Michael, Adamson, Gregory T., Marsden, Alison L., Yang, Weiguang, and Collins, R Thomas 2nd
- Published
- 2022
- Full Text
- View/download PDF
3. Distribution of mercury‐cycling genes in the Arctic and equatorial Pacific Oceans and their relationship to mercury speciation.
- Author
-
Bowman, Katlin L., Collins, R. Eric, Agather, Alison M., Lamborg, Carl H., Hammerschmidt, Chad R., Kaul, Drishti, Dupont, Christopher L., Christensen, Geoff A., and Elias, Dwayne A.
- Subjects
- *
MERCURY , *MERCURY poisoning , *OCEAN , *MICROBIAL metabolism , *SEAWATER , *POLYMERASE chain reaction , *MICROBIAL genomics - Abstract
Humans are exposed to potentially harmful amounts of the neurotoxin monomethylmercury (MMHg) through consumption of marine fish and mammals. However, the pathways of MMHg production and bioaccumulation in the ocean remain elusive. In anaerobic environments, inorganic mercury (Hg) can be methylated to MMHg through an enzymatic pathway involving the hgcAB gene cluster. Recently, hgcA‐like genes have been discovered in oxygenated marine water, suggesting the hgcAB methylation pathway, or a close analog, may also be relevant in the ocean. Using polymerase chain reaction amplification and shotgun metagenomics, we searched for but did not find the hgcAB gene cluster in Arctic Ocean seawater. However, we detected Hg‐cycling genes from the mer operon (including organomercury lyase, merB), and hgcA‐like paralogs (i.e., cdhD) in Arctic Ocean metagenomes. Our analysis of Hg biogeochemistry and marine microbial genomics suggests that various microorganisms and metabolisms, and not just the hgcAB pathway, are important for Hg methylation in the ocean. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
4. The advantages of UK Biobank's open-access strategy for health research.
- Author
-
Conroy, M., Sellors, J., Effingham, M., Littlejohns, T. J., Boultwood, C., Gillions, L., Sudlow, C. L. M., Collins, R., and Allen, N. E.
- Subjects
BIOBANKS ,EPIDEMIOLOGY ,PUBLIC health ,OPEN access publishing ,ACCESS control of databases ,COOPERATIVE research - Abstract
Ready access to health research studies is becoming more important as researchers, and their funders, seek to maximize the opportunities for scientific innovation and health improvements. Large-scale population-based prospective studies are particularly useful for multidisciplinary research into the causes, treatment and prevention of many different diseases. UK Biobank has been established as an open-access resource for public health research, with the intention of making the data as widely available as possible in an equitable and transparent manner. Access to UK Biobank's unique breadth of phenotypic and genetic data has attracted researchers worldwide from across academia and industry. As a consequence, it has enabled scientists to perform world-leading collaborative research. Moreover, open access to an already deeply characterized cohort has encouraged both public and private sector investment in further enhancements to make UK Biobank an unparalleled resource for public health research and an exemplar for the development of open-access approaches for other studies. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
5. Soil Column Simulation of Natural Nutrient Flux after Short‐term Inundation.
- Author
-
Collins, R. J., Mylavarapu, R. S., Clark, M. W., and Osborne, T. Z.
- Published
- 2019
- Full Text
- View/download PDF
6. The influence of formulation on Trichoderma biological activity and frosty pod rot management in Theobroma cacao.
- Author
-
Crozier, J., Arroyo, C., Morales, H., Melnick, R. L., Strem, M. D., Vinyard, B. T., Collins, R., Holmes, K. A., and Bailey, B. A.
- Subjects
TRICHODERMA ,SURFACE active agents ,GERMINATION ,PHYSIOLOGICAL control systems ,DRYING - Abstract
Frosty pod rot ( FPR), caused by Moniliophthora roreri, is responsible for significant losses in Theobroma cacao. Due to limited options for FPR management, biological control methods using Trichoderma are being studied. Combinations of three formulations and two Trichoderma isolates were studied between May 2009 and April 2011. The formulations were 0·3 mL L
−1 of the surfactant BreakThru 100 SL ( BT), a mixture of 1% w/v Sure-Jell (source of pectin) and 1% w/v potato dextrose broth ( PDB) ( PP), and an invert oil emulsion of 50% v/v corn oil/2·5% w/v lecithin/0·5% w/v PDB ( COP). Water and fungicide, copper oxychloride, were included as controls. Humidity chamber studies indicated that Trichoderma conidia germinated in all formulations if free water was maintained, while only the COP formulation supported germination under drying conditions. In the field, Trichoderma ovalisporum DIS-70a and Trichoderma harzianum DIS-219f were applied monthly in each of the three formulations at a rate of 180 mL per tree, 2·46 × 107 conidia per mL. The COP/ DIS-70a formulation provided the largest yield increase compared to all other treatments, including the fungicide control. Averaged over the 2 years, the COP formulation increased yield to 30·7% healthy pods compared to 9·7% healthy pods in the water control. Although the formulation/isolate combinations did not consistently increase endophytic colonization, the PP/ DIS-219f, COP/ DIS-219f and COP/ DIS-70a combinations increased total endophytic/epiphytic colonization by Trichoderma. The invert corn oil formulation of DIS-70a significantly enhanced yield of healthy cacao pods over 2 years providing a promising model for optimizing Trichoderma-based biocontrol strategies. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
7. A Comparison of Textbooks' Presentation of Fractions.
- Author
-
Cady, Jo A., Hodges, Thomas E., and Collins, R. Lee
- Subjects
STUDY & teaching of fractions ,LEARNING ,TEXTBOOKS ,CURRICULUM - Abstract
In the United States, fractions are an important part of the middle school curriculum, yet many middle school students struggle with fraction concepts. Teachers also have difficulty with the conceptual understanding needed to teach fractions and rely on textbooks when making instructional decisions. This reliance on textbooks, the idea that teaching and learning of fractions is a complex process, and that fraction understanding is the foundation for later topics such as proportionality, algebra, and probability, makes it important to examine the variation in presentation of fraction concepts in U. S. textbooks, especially the difference between traditional and standards-based curricula. The purpose of this study is to determine if differences exist in the presentation of fractions in conventional and standards-based textbooks and how these differences align with the recommendations of National Council of Teachers of Mathematics, Common Core State Standards, and the research on the teaching and learning of fractions. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
8. First lidar observation of the mesospheric nickel layer.
- Author
-
Collins, R. L., Li, J., and Martus, C. M.
- Published
- 2015
- Full Text
- View/download PDF
9. Impact of lipoprotein(a) levels and apolipoprotein(a) isoform size on risk of coronary heart disease.
- Author
-
Hopewell, J. C., Seedorf, U., Farrall, M., Parish, S., Kyriakou, T., Goel, A., Hamsten, A., Collins, R., Watkins, H., and Clarke, R.
- Subjects
LIPOPROTEINS ,APOLIPOPROTEINS ,CORONARY disease ,CONFIDENCE intervals ,HEART disease risk factors - Abstract
Objectives Observational and genetic studies have shown that lipoprotein(a) [ Lp(a)] levels and apolipoprotein(a) [apo(a)] isoform size are both associated with coronary heart disease ( CHD) risk, but the relative independence of these risk factors remains unclear. Clarification of this uncertainty is relevant to the potential of future Lp(a)-lowering therapies for the prevention of CHD. Methods Plasma Lp(a) levels and apo(a) isoform size, estimated by the number of kringle IV ( KIV) repeats, were measured in 995 patients with CHD and 998 control subjects. The associations between CHD risk and fifths of Lp(a) levels were assessed before and after adjustment for KIV repeats and, conversely, the associations between CHD risk and fifths of KIV repeats were assessed before and after adjustment for Lp(a) levels. Results Individuals in the top fifth of Lp(a) levels had more than a twofold higher risk of CHD compared with those in the bottom fifth, and this association was materially unaltered after adjustment for KIV repeats [odds ratio ( OR) 2.05, 95% confidence interval ( CI) 1.38-3.04, P < 0.001]. Furthermore, almost all of the excess risk was restricted to the two-fifths of the population with the highest Lp(a) levels. Individuals in the bottom fifth of KIV repeats had about a twofold higher risk of CHD compared with those in the top fifth, but this association was no longer significant after adjustment for Lp(a) levels ( OR 1.13, 95% CI 0.77-1.66, P = 0.94). Conclusions The effect of KIV repeats on CHD risk is mediated through their impact on Lp(a) levels, suggesting that absolute levels of Lp(a), rather than apo(a) isoform size, are the main determinant of CHD risk. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
10. Increased endothelial activation in recently symptomatic versus asymptomatic carotid artery stenosis and in cerebral microembolic-signal-negative patient subgroups.
- Author
-
Kinsella, J. A., Tobin, W. O., Kavanagh, G. F., O'Donnell, J. S., McGrath, R. T., Tierney, S., Feeley, T. M., Egan, B., O'Neill, D., Collins, R. D., Coughlan, T., Harbison, J. A., Doherty, C. P., Madhavan, P., Moore, D. J., O'Neill, S. M., Colgan, M. ‐ P., Saqqur, M., Murphy, R. P., and Moran, N.
- Subjects
VON Willebrand factor ,BIOMARKERS ,DOPPLER ultrasonography ,CAROTID artery stenosis ,STROKE diagnosis ,DIAGNOSIS ,PATIENTS - Abstract
Background and purpose von Willebrand factor propeptide ( VWF: Ag II) is potentially a more sensitive marker of acute endothelial activation than von Willebrand factor antigen ( VWF:Ag). These biomarkers have not been simultaneously assessed in asymptomatic versus symptomatic carotid stenosis patients. The relationship between endothelial activation and cerebral microembolic signals ( MESs) detected on transcranial Doppler ultrasound is unknown. Methods In this multicentre observational analytical study, plasma VWF:Ag and VWF: Ag II levels in patients with ≥50% asymptomatic carotid stenosis were compared with those from patients with ≥50% symptomatic carotid stenosis in the 'early' (≤4 weeks) and 'late' (≥3 months) phases after transient ischaemic attack or ischaemic stroke. Endothelial activation was also longitudinally assessed in symptomatic patients during follow-up. Transcranial Doppler ultrasound monitoring classified patients as MES-positive or MES-negative. Results Data from 31 asymptomatic patients were compared with those from 46 early symptomatic and 35 late phase symptomatic carotid stenosis patients, 23 of whom had undergone carotid intervention. VWF: Ag II levels were higher in early (12.8 μg/ml; P < 0.001), late (10.6 μg/ml; P = 0.01) and late post-intervention (10.6 μg/ml; P = 0.038) symptomatic patients than asymptomatic patients (8.9 μg/ml). VWF:Ag levels decreased in symptomatic patients followed up from the early to late phase after symptom onset ( P = 0.048). Early symptomatic MES-negative patients had higher VWF: Ag II levels (13.3 vs. 9.0 μg/ml; P < 0.001) than asymptomatic MES-negative patients. Conclusions Endothelial activation is enhanced in symptomatic versus asymptomatic carotid stenosis patients, in early symptomatic versus asymptomatic MES-negative patients, and decreases over time in symptomatic patients. VWF: Ag II levels are a more sensitive marker of endothelial activation than VWF:Ag levels in carotid stenosis. The potential value of endothelial biomarkers and concurrent cerebral MES detection at predicting stroke risk in carotid stenosis warrants further study. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
11. A new approach to HLA typing designed for solid organ transplantation: epityping and its application to the HLA-A locus.
- Author
-
Lougee, E., Morjaria, S., Shaw, O., Collins, R., and Vaughan, R.
- Subjects
MAJOR histocompatibility complex ,AMINO acids ,EPITOPES ,TRANSPLANTATION of organs, tissues, etc. ,POLYMERASE chain reaction ,GEL electrophoresis ,DNA - Abstract
HLA-specific antibodies bind discrete clusters of amino acids called epitopes, but serological assignment of antibody specificities makes no reference to this. As HLA typing for solid organ transplantation is provided at only medium (serologically equivalent) resolution, this means that recipient HLA antibodies to donor HLA epitopes may not be identified. We have designed a novel and rapid HLA-A epitope typing method (epityping) using a two-stage PCR- SSP-based method to detect the HLA-A locus epitopes described by El Awar et al. 2007, Transplantation, 84, 532. The initial PCR step utilizes HLA-A locus-specific primers; the product is cleaned using the QIAquick Spin Purification procedure. The purified product is tested using our in-house epitope-specific primer panel, the results being visualized using gel electrophoresis. Twenty two UCLA DNA Exchange samples were epityped, blinded to the HLA type. Of the 75 primer pairs, the mean correlation coefficient was 0.95 with each sample giving 67 or more correct primer results. In all cases, it was possible to derive the first field classic HLA type from the epityping results. These results indicate that a method for identification of HLA epitopes which is comparable in time, cost and technical expertise to current HLA typing methods is achievable. Redesigning HLA typing to correlate with what the antibody binds should minimize inappropriate organ allocation. We suggest that epityping provides a more effective method than standard HLA typing for solid organ transplantation. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
12. A case study of an elevated stratopause generated in the Whole Atmosphere Community Climate Model.
- Author
-
Chandran, A., Collins, R. L., Garcia, R. R., and Marsh, D. R.
- Published
- 2011
- Full Text
- View/download PDF
13. Canopy-microclimate effects on the antagonism between Trichoderma stromaticum and Moniliophthora perniciosa in shaded cacao.
- Author
-
Loguercio, L. L., Santos, L. S., Niella, G. R., Miranda, R. A. C., de Souza, J. T., Collins, R. T., and Pomella, A.W.V.
- Subjects
BIOLOGICAL pest control ,CACAO diseases & pests ,ANTIBIOSIS ,PLANT canopies ,LOGISTIC regression analysis ,METEOROLOGICAL stations ,PREVENTION - Abstract
The collective impact of several environmental factors on the biocontrol activity of Trichoderma stromaticum ( Ts) against Moniliophthora perniciosa ( Mp), the cause of cacao witches’ broom disease, was assessed under field conditions of shaded cacao ( Theobroma cacao) in south-eastern Bahia, Brazil. Biocontrol experiments were performed adjacent to an automated weather station, with sensors and Ts-treated brooms placed at different canopy heights. Sporulation occurred at the same dates for all Ts isolates, but in different quantities. Broom moisture >30%, air temperature of approximately 23 ± 3°C, relative humidity >90%, solar radiation intensities <0·12 KW m
− ² and wind speed near zero were the key environmental parameters that preceded Ts sporulation events. A multiple logistic regression indicated that these weather variables combined were capable of distinguishing sporulation from non-sporulation events, with a significant effect of wind speed. Analyses of environmental factors at ground level indicated similar pre-sporulation conditions, with a soil moisture content above a threshold of 0·34 m3 m−3 preceding all sporulation events. The sporulation of five selected Ts isolates was compared at four different canopy heights. Isolates responded differently to weather variation in terms of sporulation and antagonism to Mp at different canopy levels, indicating that different microclimates are established along the vertical profile of a shaded cacao plantation. The potential of these findings for development of predictive mathematical models and disease-management approaches is discussed. [ABSTRACT FROM AUTHOR]- Published
- 2009
- Full Text
- View/download PDF
14. Evenness drives consistent diversity effects in intensive grassland systems across 28 European sites.
- Author
-
Kirwan, L., Lüscher, A., Sebastià, M. T., Finn, J. A., Collins, R. P., Porqueddu, C., Helgadottir, A., Baadshaug, O. H., Brophy, C., Coran, C., Dalmannsdóttir, S., Delgado, I., Elgersma, A., Fothergill, M., Frankow-Lindberg, B. E., Golinski, P., Grieu, P., Gustavsson, A. M., Höglind, M., and Huguenin-Elie, O.
- Subjects
GRASSLANDS ,FORAGE plants ,BIOMASS ,PASTURES ,MEADOWS ,GRAZING ,PLANT species ,PLANT communities ,LEGUMES - Abstract
1 Ecological and agronomic research suggests that increased crop diversity in species-poor intensive systems may improve their provision of ecosystem services. Such general predictions can have critical importance for worldwide food production and agricultural practice but are largely untested at higher levels of diversity. 2 We propose new methodology for the design and analysis of experiments to quantify diversity-function relationships. Our methodology can quantify the relative strength of inter-specific interactions that contribute to a functional response, and can disentangle the separate contributions of species richness and relative abundance. 3 Applying our methodology to data from a common experiment at 28 European sites, we show that the above-ground biomass of four-species mixtures (two legumes and two grasses) in intensive grassland systems was consistently greater than that expected from monoculture performance, even at high productivity levels. The magnitude of this effect generally resulted in transgressive overyielding. 4 A combined analysis of first-year results across sites showed that the additional performance of mixtures was driven by the number and strength of pairwise inter-specific interactions and the evenness of the community. In general, all pairwise interactions contributed equally to the additional performance of mixtures; the grass-grass and legume-legume interactions were as strong as those between grasses and legumes. 5 The combined analysis across geographical and temporal scales in our study provides a generality of interpretation of our results that would not have been possible from individual site analyses or experimentation at a single site. 6 Our four-species agricultural grassland communities have proved a simple yet relevant model system for experimentation and development of methodology in diversity-function research. Our study establishes that principles derived from biodiversity research in extensive, semi-natural grassland systems are applicable in intensively managed grasslands with agricultural plant species. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
15. Manganese accumulation in the leaf mesophyll of four tree species: a PIXE/EDAX localization study.
- Author
-
Fernando, D. R., Bakkaus, E. J., Perrier, N., Baker, A. J. M., Woodrow, I. E., Batianoff, G. N., and Collins, R. N.
- Subjects
MANGANESE ,LEAVES ,PHOTOSYNTHESIS ,HYPERACCUMULATOR plants ,CLIFFS ,HEAVY metals - Abstract
• Little is known about the spatial distribution of excess manganese (Mn) in the leaves of tolerant plants. Recently, the first such study of a Mn hyperaccumulator showed that the highest localized Mn concentrations occur in the photosynthetic tissue. This is in contrast to reports based on localization of foliar accumulation of other heavy metals. • Here, four tree species, Gossia bidwillii, Virotia neurophylla, Macadamia integrifolia and Macadamia tetraphylla, which hyperaccumulate or strongly accumulate Mn, were studied. Cross-sectional foliar Mn localization was carried out in situ using proton-induced X-ray emission/energy dispersive X-ray analysis (PIXE/EDAX). • All four species contained photosynthetic tissues with multiple palisade layers. These were shown to be the primary sequestration sites for Mn. Mn was not detected in the epidermal tissues. • The findings of this study demonstrate a concurrence of three traits in four tree species, that is, accumulation of excess Mn in the leaves, its primary sequestration in the photosynthetic tissues, and multiple-layer palisade mesophyll. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
16. Proliferative responses and IL-2 production by mononuclear cells from bovine mammary secretions, and the effect of mammary secretions on peripheral blood lymphocytes.
- Author
-
Collins, R. A. and Oldham, G.
- Subjects
- *
IMMUNE response , *CELL proliferation , *COLOSTRUM , *LYMPHOCYTES , *CULTURES (Biology) , *MAMMARY gland secretions , *COWS - Abstract
Mammary gland mononuclear cells (MGM) were compared with peripheral blood mononuclear cells (PBM) for their ability to proliferate in response to phytohaemagglutinin (PHA), concanavalin A (Con A) and pokeweed mitogen (PWM), and to produce interleukin-2 (IL-2) when cultured with Con A. MGM proliferative responses to all three mitogens were at a level only just above background. Following removal of adherent cells by passage of the MGM population over Sephadex G10, their ability to proliferate increased but these responses were still significantly lower (P < 0.001) than those of PBM. Mammary secretions from non-lactating cows and colostrum, but not milk, were found to suppress the proliferative responses to PHA and Con A of PBM following a 24-hr preincubation period. There was no difference in IL-2 production in response to Con A by Sephadex G10-treated MGM and PBM, and dry-cow secretions had no effect on IL-2 production. [ABSTRACT FROM AUTHOR]
- Published
- 1986
17. Lidar observations of a large high-altitude sporadic Na layer during active aurora.
- Author
-
Collins, R. L., Hallinan, T. J., Smith, R. W., and Hernandez, G.
- Published
- 1996
- Full Text
- View/download PDF
18. Absence of effects of prolonged simvastatin therapy on nocturnal sleep in a large randomized placebo-controlled study.
- Author
-
KEECH, A. C., ARMITAGE, J. M., WALLENDSZUS, K. R., LAWSON, A., HAUER, A. J., PARISH, S. E., and COLLINS, R.
- Published
- 1996
- Full Text
- View/download PDF
19. First synthesis of ericoid mycorrhizas in the Epacridaceae under axenic conditions.
- Author
-
McLean, C. B., Anthony, J., Collins, R. A., Steinke, E., and Lawrie, A. C.
- Subjects
EPACRIDACEAE ,PLANT tissue culture ,ERICACEAE ,PLANT cells & tissues ,PARASITIC plants ,SYMBIOSIS - Abstract
The first axenic synthesis of morphologically typical ericoid mycorrhizas of the Epacridaceae has been achieved in micropropagated Epacris impressa Labill. with eight fungi isolated from roots of two epacrid species, E. impressa and Astyoloma pinifolium (R.Br.) Benth. Mycorrhizal synthesis has also been achieved between E. impressa and both Hymenoscyphus ericae (Read) Korf and Kernan and Oidiodendron griseum Robak, recognized endophytes of Ericaceae, suggesting that the endophytes of the Epacridaceae and Ericaceae are capable of cross-infection. Infection rate of epidermal cells on hair roots varied from 3 77% infection and the density of hyphal coils varied widely. This synthesis makes possible studies of the roles of these endophytes in the Epacridaceae and comparison with their roles in the Ericaceae. [ABSTRACT FROM AUTHOR]
- Published
- 1998
- Full Text
- View/download PDF
20. Afferent lymph veiled cells stimulate proliferative responses in allogeneic CD4+ and CD8+ T cells but not γδ TCR+ T cells.
- Author
-
Howard, C. J., Sopp, P., Brownlie, J., Parsons, K. R., Kwong, L.-S., and Collins, R. A.
- Subjects
DENDRITIC cells ,MONOCLONAL antibodies ,ANTIGENS ,T cells ,MAJOR histocompatibility complex ,PROTEINS ,POLYMERASE chain reaction - Abstract
Dendritic cells were identified in afferent lymph derived by lymphatic cannulation of cattle, stained with monoclonal antibody (mAb) to the bovine workshop cluster 6 (WC6) antigen, which is highly expressed on bovine afferent lymph veiled cells, and sorted with a fluorescence-activated cell sorter. These cells expressed major histocompatibility complex (MHC) class I and II and CD1b but not CD14. They bound human and routine CTLA4-immunoglobulin (CTLA4-Ig) fusion proteins indicating expression of CD80 and or CD86. Dendritic cells induced proliferative responses in allogeneic CD4
+ and CD8+ cells sorted from blood but did not induce responses in purified allogeneic WC1+ , γ/δ T cells, which are CD2- , CD4- , CD8- and are the major γδ T-cell population in cattle blood, even when interleukin-2 (IL-2) was added to cultures. A WC1- , CD2+ γδ T-cell receptor (TCR)+ population predominates in cattle spleens and proliferation of a T-cell line with this phenotype was not induced by aliogeneic dendritic cells, with or without added IL-2. The observations imply that the ligand for the γδ TCR expressed on the two populations is not present on allogeneic dendritic cells or that the costimulatory molecules expressed on dendritic cells that render them highly effective at stimulating MHC class I- and class II-restricted CD8+ and CD4+ T cells are not recognized by the WC1+ or WC1- γ/δ T cells. Expression of CD28 by the four cell types was assessed by reverse transcriptase-polymerase chain reaction (RT-PCR). Purified CD4+ and CD8+ cells both produced CD28 transcripts but neither purified WC1+ cells nor the WC1- γδ TCR+ cell line did so. The findings indicate that CD80 and or CD86 are involved in the stimulation of CD4+ and CD8+ αβ TCR+ T cells but not in the stimulation of either of the two γδ TCR+ populations. [ABSTRACT FROM AUTHOR]- Published
- 1996
- Full Text
- View/download PDF
21. CD45RO expression on bovine T cells: relation to biological function.
- Author
-
Bembridge, G. P., MacHugh, N. D., McKeever, D., Awino, E., Sopp, P., Collins, R. A., Gelder, K. I., and Howard, C. J.
- Subjects
T cells ,GENE expression ,INTERLEUKIN-2 ,MONOCLONAL antibodies ,ENZYME-linked immunosorbent assay ,POLYMERASE chain reaction - Abstract
The 180000 MW isoform of CD45 (CD45RO) has been identified in cattle with a novel monoclonal antibody (mAb) (IL-A116). This has allowed a more precise analysis of T-cell function in relation to CD45 isoform expression. Within the CD4
4 and CD8+ T-cell populations, CD45RO+ and CD45RO- subsets were evident. Most CD4+ and CD8- T cells that expressed the CD45RO isoform did not express the 220000 and 205000 MW isoforms recognized by mAb CC76. In contrast, the WCI+ , CD2- , CD4- , CD8+ , γδ T-cell receptor (TCR)+ T cells in bovine peripheral blood mononuclear cells (PBMC) were all CD45RO+ . Monocytes and granulocytes were CD45RO+ but B cells were CD45RO+ . Sorting experiments with CD4+ T cells from an immunized calf demonstrated that proliferative responses to ovalbumin (OVA) were entirely within the CD45RO+ subset. Following stimulation with concanavalin A (Con A) the CD45RO- subset of CD4+ T cells produced transcripts for interleukin-2 (IL-2) but not IL-4 or interferon-γ (IFN-γ), while the CD45R0+ subset produced mRNA for IL-2, IL-4 and IFN-γ. Biologically active IL-2 was present in supernatants from both CD45RO+ and CD45RO- , CD4+ T cells, and IFN-γ protein was identified by ELISA in supernatants from the CD45RO+ subset, confirming the production of cytokines implied by polymerase chain reaction (PCR). In contrast, sorting experiments with CD8+ T cells from animals immune to the protozoan parasite Theileriaparva revealed substantial numbers of cytotoxic T-lymphocyte precursors in both the CD45RO+ and CD45RO- subsets. Thus it appears that although all antigenically primed CD4+ T cells remain CD45RO+ , and expression of this molecule consequently identifies memory cells within PBMC, antigenically primed CD8+ T cells down-regulate CD45RO expression after activation. [ABSTRACT FROM AUTHOR]- Published
- 1995
22. Rheumatoid arthritis and small airways function.
- Author
-
Mountz, J. D., Turner, R. A., Collins, R. L., Gallup, K. R., and Semble, E. L.
- Published
- 1984
- Full Text
- View/download PDF
23. Short report: treatment of Helicobacter pylori-associated duodenal ulcer with omeprazole plus antibiotics.
- Author
-
McCARTHY, C. J., COLLINS, R., BEATTIE, S., HAMILTON, H., and O'MORAIN, C.
- Published
- 1993
- Full Text
- View/download PDF
24. Report of Seed and Meal Analysis Committee, 1947-48.
- Author
-
Brown, L., Gerhart, Leonard, Smith, T., Dippold, M., Anderson, R., Earle, F., Freyer, E., Geddes, W., Gunther, J., Mehlenbacher, V., Laing, M., Potts, T., Pohle, W., Collins, R., Ainslie, E., Cox, C., Conner Henry, G., law, T., Andrews, R., and Worthen Agee, G.
- Published
- 1948
- Full Text
- View/download PDF
25. PERSONNEL SPECIALISTS--A COUNT BY EMPLOYERS.
- Author
-
Crichton, Anne and Collins, R. G.
- Subjects
EXECUTIVES ,EMPLOYMENT ,SURVEYS ,WORKFORCE planning ,INDUSTRIAL management ,EMPLOYMENT of executives - Abstract
This article focuses on a survey about the employment and distribution of executives conducted in South Wales. The first question had been followed by a list of twenty-four common job titles in the field of personnel management in order to indicate to the organizations what were the commonly accepted personnel specialist activities. Respondents of the survey were asked to include safety officers and medical staff, but to exclude security staff and catering staffs unless these had any other personnel duties.
- Published
- 1966
- Full Text
- View/download PDF
26. Catastrophic arterial thrombosis associated with an unsuspected anticardiolipin antibody, following pyelography.
- Author
-
Collins, R. Deaver
- Published
- 1989
- Full Text
- View/download PDF
27. Short report: high-dose omeprazole and amoxycillin in the treatment of Helicobacter pylori-associated duodenal ulcer.
- Author
-
COLLINS, R., BEATTIE, S., XIA, H. X., and O'MORAIN, C.
- Published
- 1993
- Full Text
- View/download PDF
28. Body Composition and Risk of Vascular-Metabolic Mortality Risk in 113 000 Mexican Men and Women Without Prior Chronic Disease.
- Author
-
Gnatiuc Friedrichs L, Wade R, Alegre-Díaz J, Ramirez-Reyes R, Garcilazo-Ávila A, Gonzáles-Carballo C, Santacruz-Benitez R, Chiquete E, Herrington W, Collins R, Peto R, Clarke R, Berumen J, Emberson JR, Kuri-Morales P, and Tapia-Conyer R
- Subjects
- Adult, Male, Humans, Female, Prospective Studies, Mexico epidemiology, Body Mass Index, Chronic Disease, Body Composition
- Abstract
Background Body-mass index is the sum of fat mass index (FMI) and lean mass index (LMI), which vary by age, sex, and impact on disease outcomes. We investigated the separate and joint relevance of FMI and LMI with vascular-metabolic causes of death in Mexican adults. Methods and Results A total of 113 025 adults aged 35 to 74 years and free from diabetes or other chronic diseases when recruited into the Mexico City Prospective Study were followed for 19 years. Cox models estimated sex-specific death rate ratios from vascular-metabolic causes after adjustment for confounders and exclusion of the first 5 years of follow-up. To account for the strong correlation between FMI and LMI, additional models estimated rate ratios associated with "residual FMI" and "residual LMI" (ie, the residuals from linear regression analyses of FMI on LMI, or vice versa). In both sexes, higher FMI and LMI were associated with higher risks of vascular-metabolic mortality. For a given (ie, fixed) level of LMI, the rate ratio (95% CI) for vascular-metabolic mortality per 1 kg/m
2 higher residual FMI strengthened and was higher in women (1.52 [1.38-1.68]) than in men (1.19 [1.13-1.25]). By contrast, for a given level of FMI, higher residual LMI was inversely associated with vascular-metabolic mortality (rate ratio per 1 kg/m2 0.67 [0.56-0.80] in women and 0.94 [0.90-0.98] in men). Conclusions In this study, higher residual FMI was more strongly associated with vascular-metabolic mortality in women than in men. Conversely, higher residual LMI was inversely associated with vascular-metabolic mortality, particularly in women.- Published
- 2023
- Full Text
- View/download PDF
29. The number of postoperative surgical or diagnostic procedures following congenital heart surgery correlates with both mortality and hospital length of stay.
- Author
-
Capecci L, Mainwaring RD, Collins RT, Sidell D, Martin E, Lamberti JJ, and Hanley FL
- Subjects
- Hospital Mortality, Hospitals, Humans, Length of Stay, Postoperative Complications, Postoperative Period, Retrospective Studies, Risk Factors, Cardiac Surgical Procedures, Heart Defects, Congenital diagnosis, Heart Defects, Congenital surgery
- Abstract
Background: Outcomes for congenital heart disease have dramatically improved over the past several decades. However, there are patients who encounter intraoperative or postoperative complications and ultimately do not survive. It was our hypothesis that the number of postoperative procedures (including surgical and unplanned diagnostic procedures) would correlate with hospital length of stay and operative mortality., Methods: This was a retrospective review of 938 consecutive patients undergoing congenital heart surgery at a single institution over a 2-year timeframe. The number of postoperative surgical and unplanned diagnostic procedures were counted and the impact on hospital length of stay and mortality was assessed., Results: 581 of the 938 (62%) patients had zero postoperative diagnostic or surgical procedures. These patients had a median length of stay of 6 days with a single operative mortality (0.2%). 357 of the 938 (38%) patients had one or more postoperative diagnostic or surgical procedures. These patients had a total of 1586 postoperative procedures. There was a significant correlation between the number of postoperative procedures and both hospital length of stay and mortality (p < .001). Patients who required 10 or more postoperative procedures had a median hospital length of stay of 89 days and had a 50% mortality. There were no survivors in patients who had 15 or more postoperative procedures., Conclusions: The data demonstrate that the number of postoperative procedures was highly correlated with both hospital length of stay and mortality., (© 2022 Wiley Periodicals LLC.)
- Published
- 2022
- Full Text
- View/download PDF
30. The association between increasing oral anticoagulant prescribing and atrial fibrillation related stroke in Ireland.
- Author
-
Kennedy C, Gabr A, McCormack J, Collins R, Barry M, and Harbison J
- Subjects
- Administration, Oral, Anticoagulants adverse effects, Humans, Ireland epidemiology, Atrial Fibrillation complications, Atrial Fibrillation drug therapy, Atrial Fibrillation epidemiology, Brain Ischemia epidemiology, Brain Ischemia etiology, Brain Ischemia prevention & control, Ischemic Stroke, Stroke epidemiology, Stroke etiology, Stroke prevention & control
- Abstract
Aims: Recent increases in the number of patients with atrial fibrillation (AF) prescribed oral anticoagulants (OAC) are evident in Ireland and internationally, largely due to the availability of direct oral anticoagulants (DOACs). This study aimed to determine the rate of stroke in the context of increasing anticoagulation utilisation, with a focus on AF-related ischaemic stroke (IS)., Methods: Dispensing data for OACs were identified for the period 2010-2018 as well as hospital discharges for IS (2005-2018). Irish National Stroke Register data were used to elucidate the characteristics of patients with acute ischaemic stroke., Results: The number of patients prescribed OACs increased by 94% from 2010-2018 with a significant change from 2013 (β = 2.57, P = .038), associated with a large increase in the number of patients on DOACs. There was 3.3-fold increase in expenditure on OACs nationally from 2013 to 2018, of which 94% was DOAC related. Using the 2013 timepoint, ischaemic stroke rates until 2018 did not show a significant deviation from the previous trend (β = 0.00, P = .898). The percentage of AF-related ischaemic stroke was stable from 2013 to 2017 with a 4.5% decrease in 2018. The percentage of ischaemic stroke patients with previously diagnosed AF decreased from 2013 to 2018; however, there was an increase in the percentage of ischaemic strokes while on OAC in this cohort., Conclusion: Large increases in OAC utilisation have not resulted in changes in ischaemic stroke rates at a national level. The percentage of ischaemic strokes with a previous diagnosis of AF has decreased indicating a possible benefit from greater OAC utilisation. However, the percentage presenting with an ischaemic stroke while on OAC treatment is increasing. The increase in patients presenting with stroke while treated with OAC may largely reflect the national increase in patients prescribed DOACs but the findings raise concerns about treatment failures. The real-world effectiveness of DOACs requires further examination., (© 2021 The Authors. British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)
- Published
- 2022
- Full Text
- View/download PDF
31. Use of a Clinical Electrocardiographic Database to Enhance Atrial Fibrillation/Atrial Flutter Identification Algorithms Based on Administrative Data.
- Author
-
Liu H, Collins R, Miller RJH, Southern DA, Arena R, Aggarwal S, Sajobi T, James MT, and Wilton SB
- Subjects
- Algorithms, Canada epidemiology, Clinical Decision Rules, Data Accuracy, Diagnosis, Differential, Humans, Incidence, Quality Improvement organization & administration, Sensitivity and Specificity, Atrial Fibrillation diagnosis, Atrial Fibrillation epidemiology, Atrial Flutter diagnosis, Atrial Flutter epidemiology, Clinical Coding methods, Clinical Coding standards, Databases, Factual standards, Databases, Factual statistics & numerical data, Electrocardiography methods, Electrocardiography statistics & numerical data
- Abstract
Background Administrative data have limited sensitivity for case finding of atrial fibrillation/atrial flutter (AF/AFL). Linkage with clinical repositories of interpreted ECGs may enhance diagnostic yield of AF/AFL. Methods and Results We retrieved 369 ECGs from the institutional Marquette Universal System for Electrocardiography (MUSE) repository as validation samples, with rhythm coded as AF (n=49), AFL (n=50), or other competing rhythm diagnoses (n=270). With blinded, duplicate review of ECGs as the reference comparison, we compared multiple MUSE coding definitions for identifying AF/AFL. We tested the agreement between MUSE diagnosis and reference comparison, and calculated the sensitivity and specificity. Using a data set linking clinical registries, administrative data, and the MUSE repository (n=11 662), we assessed the incremental diagnostic yield of AF/AFL by incorporating ECG data to administrative data-based algorithms. The agreement between MUSE diagnosis and reference comparison depended on the coding definitions applied, with the Cohen κ ranging from 0.57 to 0.75. Sensitivity ranged from 60.6% to 79.1%, and specificity ranged from 93.2% to 98.0%. A coding definition with AF/AFL appearing in the first 3 ECG statements had the highest sensitivity (79.1%), with little loss of specificity (94.5%). Compared with the algorithms with only administrative data, incorporating ECG data increased the diagnostic yield of preexisting AF/AFL by 14.5% and incident AF/AFL by 7.5% to 16.1%. Conclusions Routine ECG interpretation using MUSE coding is highly specific and moderately sensitive for AF/AFL detection. Inclusion of MUSE ECG data in AF/AFL case identification algorithms can identify cases missed using administrative data-based algorithms alone.
- Published
- 2021
- Full Text
- View/download PDF
32. Outcomes in Antiplatelet-Associated Intracerebral Hemorrhage in the TICH-2 Randomized Controlled Trial.
- Author
-
Law ZK, Desborough M, Roberts I, Al-Shahi Salman R, England TJ, Werring DJ, Robinson T, Krishnan K, Dineen R, Laska AC, Peters N, Egea-Guerrero JJ, Karlinski M, Christensen H, Roffe C, Bereczki D, Ozturk S, Thanabalan J, Collins R, Beridze M, Bath PM, and Sprigg N
- Subjects
- Aged, Antifibrinolytic Agents therapeutic use, Cerebral Hemorrhage diagnosis, Cerebral Hemorrhage physiopathology, Disease Progression, Dose-Response Relationship, Drug, Double-Blind Method, Female, Follow-Up Studies, Humans, Male, Prognosis, Prospective Studies, Cerebral Hemorrhage chemically induced, Platelet Aggregation Inhibitors adverse effects, Tranexamic Acid therapeutic use
- Abstract
Background Antiplatelet therapy increases the risk of hematoma expansion in intracerebral hemorrhage (ICH) while the effect on functional outcome is uncertain. Methods and Results This is an exploratory analysis of the TICH-2 (Tranexamic Acid in Intracerebral Hemorrhage-2) double-blind, randomized, placebo-controlled trial, which studied the efficacy of tranexamic acid in patients with spontaneous ICH within 8 hours of onset. Multivariable logistic regression and ordinal regression were performed to explore the relationship between pre-ICH antiplatelet therapy, and 24-hour hematoma expansion and day 90 modified Rankin Scale score, as well as the effect of tranexamic acid. Of 2325 patients, 611 (26.3%) had pre-ICH antiplatelet therapy. They were older (mean age, 75.7 versus 66.5 years), more likely to have ischemic heart disease (25.4% versus 2.7%), ischemic stroke (36.2% versus 6.3%), intraventricular hemorrhage (40.2% versus 27.5%), and larger baseline hematoma volume (mean, 28.1 versus 22.6 mL) than the no-antiplatelet group. Pre-ICH antiplatelet therapy was associated with a significantly increased risk of hematoma expansion (adjusted odds ratio [OR], 1.28; 95% CI, 1.01-1.63), a shift toward unfavorable outcome in modified Rankin Scale (adjusted common OR, 1.58; 95% CI, 1.32-1.91) and a higher risk of death at day 90 (adjusted OR, 1.63; 95% CI, 1.25-2.11). Tranexamic acid reduced the risk of hematoma expansion in the overall patients with ICH (adjusted OR, 0.76; 95% CI, 0.62-0.93) and antiplatelet subgroup (adjusted OR, 0.61; 95% CI, 0.41-0.91) with no significant interaction between pre-ICH antiplatelet therapy and tranexamic acid (P interaction=0.248). Conclusions Antiplatelet therapy is independently associated with hematoma expansion and unfavorable functional outcome. Tranexamic acid reduced hematoma expansion regardless of prior antiplatelet therapy use. Registration URL: https://www.isrctn.com; Unique identifier: ISRCTN93732214.
- Published
- 2021
- Full Text
- View/download PDF
33. Carotid Intima-Media Thickness but Not Carotid Artery Plaque in Healthy Individuals Is Linked to Lean Body Mass.
- Author
-
Arnold M, Linden A, Clarke R, Guo Y, Du H, Bian Z, Wan E, Yang M, Wang L, Chen Y, Chen J, Long H, Gu Q, Collins R, Li L, Chen Z, and Parish S
- Subjects
- Female, Humans, Male, Middle Aged, Thinness, Ultrasonography, Body Composition, Carotid Intima-Media Thickness, Carotid Stenosis diagnostic imaging
- Abstract
Background Lean body mass has been identified as a key determinant of left ventricular mass and wall thickness. However, the importance of lean body mass or other body-size measures as normative determinants of carotid intima-media thickness (cIMT), a widely used early indicator of atherosclerosis, has not been well established. Methods and Results Carotid artery ultrasound measurements of cIMT and carotid artery plaque burden (derived from plaque number and maximum size) and measurements of body size, including height, body mass index, weight, body fat proportion, and lean body mass ([1-body fat proportion]×weight), were recorded in 25 020 participants from 10 regions of China. Analyses were restricted to a healthy younger subset (n=6617) defined as never or long-term ex-regular smokers aged <60 years (mean age, 50) without previous ischemic heart disease, stroke, diabetes mellitus, or hypertension and with plasma non-high-density lipoprotein cholesterol <4 mmol/L. Among these 6617 participants, 86% were women (because most men smoked) and 9% had carotid artery plaque. In both women and men separately, lean body mass was strongly positively associated with cIMT, but was not associated with plaque burden: overall, each 10 kg higher lean body mass was associated with a 0.03 (95% CI, 0.03-0.04) mm higher cIMT (P=5×10
-33 ). Fat mass, height, and other body-size measures were more weakly associated with cIMT. Conclusions The strong association of lean body mass with cIMT, but not with plaque burden, in healthy adults suggests a normative relationship rather than reflecting atherosclerotic pathology. Common mechanisms may underlie the associations of lean body mass with cIMT and with nonatherosclerotic vascular traits.- Published
- 2019
- Full Text
- View/download PDF
34. Gait variability in Parkinson's disease: levodopa and walking direction.
- Author
-
Bryant MS, Rintala DH, Hou JG, Collins RL, and Protas EJ
- Subjects
- Aged, Female, Gait Disorders, Neurologic etiology, Humans, Male, Middle Aged, Parkinson Disease complications, Antiparkinson Agents therapeutic use, Gait drug effects, Gait Disorders, Neurologic drug therapy, Levodopa therapeutic use, Parkinson Disease drug therapy
- Abstract
Background: Levodopa treatment has been shown to improve gait spatio-temporal characteristics in both forward and backward walking. However, effect of levodopa on gait variability during backward walking compared with forward walking has not been reported., Aims of Study: To study the effects of levodopa on gait variability of forward and backward walking in individuals with Parkinson's disease (PD)., Methods: Forty individuals with PD were studied. Their mean age was 68.70 ± 7.46 year. The average time since diagnosis was 9.41 ± 5.72 year. Gait variability was studied while 'OFF' and 'ON' levodopa when the participants walked forward and backward at their usual speed. Variability in step time, swing time, stride length, double support time, and stride velocity were compared between medication condition and walking direction., Results: Variability of step time, swing time, stride length, and stride velocity decreased significantly during forward and backward walks (P < 0.001; P < 0.001; P = 0.003, P = 0.001, respectively) after levodopa administration. Variability of double support time was not changed after levodopa administration (P = 0.054)., Conclusions: Levodopa had positive effects on gait variability of forward and backward walking in individuals with PD. However, variability in double support time was not affected by the levodopa., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2016
- Full Text
- View/download PDF
35. Tenidap in rheumatoid arthritis. A 24-week double-blind comparison with hydroxychloroquine-plus-piroxicam, and piroxicam alone.
- Author
-
Blackburn WD Jr, Prupas HM, Silverfield JC, Poiley JE, Caldwell JR, Collins RL, Miller MJ, Sikes DH, Kaplan H, and Fleischmann R
- Subjects
- Adult, Aged, Aged, 80 and over, Alanine Transaminase blood, Anti-Inflammatory Agents, Non-Steroidal adverse effects, Antirheumatic Agents adverse effects, Arthritis, Rheumatoid blood, Arthritis, Rheumatoid complications, C-Reactive Protein analysis, Double-Blind Method, Drug Therapy, Combination, Female, Humans, Hydroxychloroquine adverse effects, Indoles adverse effects, Interleukin-6 blood, Male, Middle Aged, Oxindoles, Piroxicam adverse effects, Proteinuria chemically induced, Time Factors, Treatment Outcome, Anti-Inflammatory Agents, Non-Steroidal administration & dosage, Antirheumatic Agents administration & dosage, Arthritis, Rheumatoid drug therapy, Hydroxychloroquine administration & dosage, Indoles administration & dosage, Piroxicam administration & dosage
- Abstract
Objective: To compare the clinical efficacy, effect on serum C-reactive protein (CRP), serum amyloid A (SAA), and plasma interleukin-6 (IL-6) levels, and safety of tenidap with a combination of hydroxychloroquine-plus-piroxicam, and piroxicam alone, in the treatment of rheumatoid arthritis (RA) patients., Methods: A double-blind, randomized, multicenter study in which patients with active RA were treated with tenidap 120 mg/day, hydroxychloroquine 400 mg/day and piroxicam 20 mg/day, or piroxicam alone 20 mg/day, for 24 weeks., Results: At weeks 12 and 24, tenidap produced greater improvements than piroxicam based on 5 primary efficacy parameters; this improvement showed statistical significance in 4 of the 5 measures at week 12, and in 3 of the 5 measures at week 24. Clinical improvements in the hydroxychloroquine-plus-piroxicam-treated with tenidap. Compared with piroxicam, tenidap was associated with significantly greater reductions in serum CRP concentrations at 4, 12, and 24 weeks, and significantly greater reductions in SAA concentrations at weeks 12 and 24. The decrease in SAA concentrations was also significantly greater at weeks 4 and 24 in the tenidap-treated group than in the hydroxychloroquine-plus-piroxicam-treated group. Significant reductions in plasma IL-6 levels were observed at weeks 4, 12, and 24 within the tenidap group, and at week 24 within the hydroxychloroquine-plus-piroxicam-treated group. The overall occurrence of side effects, including gastrointestinal side effects, was similar in all 3 treatment groups. A small proportion of tenidap-treated patients (6.4%) manifested mild, nonprogressive, reversible proteinuria of presumed renal proximal tubular origin, and 3-4% of patients had elevated transaminase levels., Conclusion: In the treatment of patients with RA, tenidap is as effective as the combination of hydroxychloroquine-plus-piroxicam, and is more effective than piroxicam alone; moreover, tenidap's safety profile is comparable to that observed with piroxicam alone, and with hydroxychloroquine-plus-piroxicam. The clinical response observed in this study, as well as the prompt decreases in acute-phase protein levels of CRP and SAA, and in plasma IL-6 levels, suggest that tenidap represents a new type of antiarthritic medication, with properties similar to, but not identical to, a therapeutic combination of a nonsteroidal antiinflammatory drug with disease-modifying antirheumatic drugs.
- Published
- 1995
- Full Text
- View/download PDF
36. Obstructive pulmonary disease in rheumatoid arthritis.
- Author
-
Collins RL, Turner RA, Johnson AM, Whitley NO, and McLean RL
- Subjects
- Adult, Aged, Arthritis, Rheumatoid genetics, Female, Humans, Lung Diseases, Obstructive diagnostic imaging, Lung Diseases, Obstructive genetics, Male, Middle Aged, Phenotype, Radiography, Respiratory Function Tests, Smoking complications, Ventilation-Perfusion Ratio, alpha 1-Antitrypsin analysis, Arthritis, Rheumatoid complications, Lung Diseases, Obstructive etiology
- Abstract
Twenty-six of 43 patients (60.5%) with classic rheumatoid arthritis (RA) participating in a controlled, prospective study were found to have maximal midexpiratory flow rates (MMEFs) suggestive of obstructive pulmonary disease. Cigarette smokers with RA had significantly lower MMEFs than either nonsmokers with RA or smokers with degenerative joint disease. There was an increased prevalence of the Pi phenotype MS among the RA patients. Interstitial fibrosis, tobacco smoking, and protease inhibitor deficiencies were all significant factors in producing airway obstruction in patients with RA.
- Published
- 1976
- Full Text
- View/download PDF
37. Plasma levels and beta-adrenoceptor blockade with acebutolol, practolol and propranolol in man.
- Author
-
Cuthbert MF and Collins RF
- Subjects
- Acebutolol blood, Adult, Dose-Response Relationship, Drug, Heart Rate drug effects, Humans, Isoproterenol antagonists & inhibitors, Male, Practolol blood, Propranolol blood, Acebutolol pharmacology, Practolol pharmacology, Propranolol pharmacology
- Abstract
1 The degree of beta-adrenoceptor blockade of isoprenaline-induced tachycardia has been determined in three healthy volunteers after the administration of single oral doses of acebutolol, practolol or propranolol. 2 Plasma levels of these drugs were determined either colorimetrically (acebutolol and practolol) or fluorimetrically (propranolol). The colorimetric assay of acebutolol in plasma is fully described but the other drugs were assayed by published methods. 3 The degree of beta-adrenoceptor blockade and the plasma level for acebutolol and practolol were well correlated, whereas in the case of propranolol correlation was poor, due in part to the presence in plasma of active metabolites not detected by the fluorimetric assay. The plasma levels of practolol and propranolol are in agreement with those previously reported. 4 The maximum cardiac beta-adrenoceptor blockade achieved in this study with the respective single oral doses of acebutolol (300 mg), practolol (400 mg) or propranolol (40 mg) were similar in each of the three subjects. Therefore the beta-adrenoceptor blocking potencies of these drugs against isoprenaline-induced tachycardia are inversely related to these doses; indicating that propranolol is 7-8 times more potent than acebutolol and the latter slightly more potent than practolol.
- Published
- 1975
- Full Text
- View/download PDF
38. Comparative effects of acebutolol and practolol on the lipolytic response to isoprenaline.
- Author
-
Gibbons DO, Lant AF, Ashford A, Collins RF, and Pinder S
- Subjects
- Adult, Animals, Blood Pressure drug effects, Fatty Acids, Nonesterified metabolism, Heart Rate drug effects, Humans, In Vitro Techniques, Male, Middle Aged, Placebos, Propranolol pharmacology, Rats, Acebutolol pharmacology, Isoproterenol antagonists & inhibitors, Lipid Metabolism, Practolol pharmacology
- Abstract
1 The effects of beta-adrenoceptor blockade on the metabolic responses to isoprenaline have been studied in an in vitro system of isolated fat cells and in six normal subjects. 2 The inhibitory effects of varying concentrations of acebutolol, practolol and propranolol on free fatty acid (FFA) release produced by isoprenaline (10(-7) M) were compared in isolated fat cells prepared from rat epididymal adipose tissue. Acebutolol and practolol, at equimolar concentrations, showed a similar inhibitory effect whilst propranolol was approximately 100 times more potent then either drug. At 10(-5)M concentration of propranolol, lipolysis was virtually abolished whilst at the same molar concentration, acebutolol and practolol halved the response. 3 Six healthy volunteers received three successive 15 min intravenous isoprenaline challenges (0.03 mug kg-1 min-1) per individual experiment. The first acted as a control whilst the following two were given either after single oral doses of placebo, acebutolol or practolol. The mean (+/- s.e. mean) basal FFA level was 0.77 +/- 0.06 mE1/1 and subsequent resting values after the administration of placebo or beta-adrenoceptor blocker were not significantly different. 4 Acebutolol inhibited the respective mean rises in FFA, produced by both post-control isoprenaline challenges, by (mean +/- s.e. mean) 70 +/- 4% and 84% +/- 5%. The comparable figures for practolol were 33 +/- 15% and 24 +/- 20%. The higher serum concentration of acebutolol produced greater inhibition but correlation of log serum concentration of the drug with percentage inhibition of FFA rise did not achieve significance. 5 Administration of isoprenaline, acebutolol or practolol did not significantly alter serum glucose, triglyceride or cholesterol levels. 6 Acebutolol and practolol effectively blocked the isoprenaline-induced tachycardia. The degree of blockade produced by practolol was greater than its inhibitory effect on FFA release. The diatolic fall in blood pressure in response to isoprenaline was abolished by acebutolol suggesting that its beta-adrenoceptor blocking action encompasses peripheral vascular sites. The comparable effect with practolol was a partial inhibition of the diastolic fall.
- Published
- 1976
- Full Text
- View/download PDF
39. Proceedings: Cardiopulmonary manifestations of systemic lupus erythematosus (SLE).
- Author
-
Hunt R, Turner R, Collins R, and McLean R
- Subjects
- Humans, Heart Diseases etiology, Lung Diseases, Obstructive etiology, Lupus Erythematosus, Systemic complications
- Published
- 1975
40. Proceedings: Small airways disease in rheumatoid arthritis.
- Author
-
Collins R, Turner R, Leyrer T, and Mclean R
- Subjects
- Arthritis, Rheumatoid physiopathology, Humans, Lung physiopathology, Pleura physiopathology, Prospective Studies, Respiratory Function Tests, United States, Airway Obstruction etiology, Arthritis, Rheumatoid complications
- Published
- 1974
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.