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Wilbourn RV, Froy H, McManus MC, Cheynel L, Gaillard JM, Gilot-Fromont E, Regis C, Rey B, Pellerin M, Lemaître JF, Nussey DH. Age-dependent associations between telomere length and environmental conditions in roe deer. Biol Lett 2017; 13:rsbl.2017.0434. [PMID: 28954855 PMCID: PMC5627176 DOI: 10.1098/rsbl.2017.0434] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 09/06/2017] [Indexed: 12/29/2022] Open
Abstract
Telomere length (TL) represents a promising biomarker of overall physiological state and of past environmental experiences, which could help us understand the drivers of life-history variation in natural populations. A growing number of studies in birds suggest that environmental stress or poor environmental conditions are associated with shortened TL, but studies of such relationships in wild mammals are lacking. Here, we compare leucocyte TL from cross-sectional samples collected from two French populations of roe deer which experience different environmental conditions. We found that, as predicted, TL was shorter in the population experiencing poor environmental conditions but that this difference was only significant in older individuals and was independent of sex and body mass. Unexpectedly, the difference was underpinned by a significant increase in TL with age in the population experiencing good environmental conditions, while there was no detectable relationship with age in poor conditions. These results demonstrate both the environmental sensitivity and complexity of telomere dynamics in natural mammal populations, and highlight the importance of longitudinal data to disentangle the within- and among-individual processes that generate them.
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Affiliation(s)
- Rachael V Wilbourn
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh EH9 3FL, UK
| | - Hannah Froy
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh EH9 3FL, UK
| | | | - Louise Cheynel
- CNRS, Université Lyon 1, Laboratoire de Biométrie et Biologie Evolutive UMR5558, 69622 Villeurbanne, France
| | - Jean-Michel Gaillard
- CNRS, Université Lyon 1, Laboratoire de Biométrie et Biologie Evolutive UMR5558, 69622 Villeurbanne, France
| | - Emmanuelle Gilot-Fromont
- CNRS, Université Lyon 1, Laboratoire de Biométrie et Biologie Evolutive UMR5558, 69622 Villeurbanne, France
| | - Corinne Regis
- CNRS, Université Lyon 1, Laboratoire de Biométrie et Biologie Evolutive UMR5558, 69622 Villeurbanne, France
| | - Benjamin Rey
- CNRS, Université Lyon 1, Laboratoire de Biométrie et Biologie Evolutive UMR5558, 69622 Villeurbanne, France
| | - Maryline Pellerin
- Office National de la Chasse et de la Faune Sauvage, Unité Cervidés-Sanglier, Bar-le-Duc, France
| | - Jean-François Lemaître
- CNRS, Université Lyon 1, Laboratoire de Biométrie et Biologie Evolutive UMR5558, 69622 Villeurbanne, France
| | - Daniel H Nussey
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh EH9 3FL, UK
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Dillon SM, Lee EJ, Kotter CV, Austin GL, Gianella S, Siewe B, Smith DM, Landay AL, McManus MC, Robertson CE, Frank DN, McCarter MD, Wilson CC. Gut dendritic cell activation links an altered colonic microbiome to mucosal and systemic T-cell activation in untreated HIV-1 infection. Mucosal Immunol 2016; 9:24-37. [PMID: 25921339 PMCID: PMC4626441 DOI: 10.1038/mi.2015.33] [Citation(s) in RCA: 148] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 03/03/2015] [Indexed: 02/04/2023]
Abstract
HIV-1-associated disruption of intestinal homeostasis is a major factor contributing to chronic immune activation and inflammation. Dendritic cells (DCs) are crucial in maintaining intestinal homeostasis, but the impact of HIV-1 infection on intestinal DC number and function has not been extensively studied. We compared the frequency and activation/maturation status of colonic myeloid DC (mDC) subsets (CD1c(+) and CD1c(neg)) and plasmacytoid DCs in untreated HIV-1-infected subjects with uninfected controls. Colonic mDCs in HIV-1-infected subjects had increased CD40 but decreased CD83 expression, and CD40 expression on CD1c(+) mDCs positively correlated with mucosal HIV-1 viral load, with mucosal and systemic cytokine production, and with frequencies of activated colon and blood T cells. Percentage of CD83(+)CD1c(+) mDCs negatively correlated with frequencies of interferon-γ-producing colon CD4(+) and CD8(+) T cells. CD40 expression on CD1c(+) mDCs positively associated with abundance of high prevalence mucosal Prevotella copri and Prevotella stercorea but negatively associated with a number of low prevalence mucosal species, including Rumminococcus bromii. CD1c(+) mDC cytokine production was greater in response to in vitro stimulation with Prevotella species relative to R. bromii. These findings suggest that, during HIV infection, colonic mDCs become activated upon exposure to mucosal pathobiont bacteria leading to mucosal and systemic immune activation.
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Affiliation(s)
- S M Dillon
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - E J Lee
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - C V Kotter
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - G L Austin
- Department of Gastroenterology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - S Gianella
- Division of Infectious Diseases, University of California San Diego, La Jolla, California, USA
| | - B Siewe
- Department of Immunology-Microbiology, Rush University Medical Center, Chicago, Illinois, USA
| | - D M Smith
- Division of Infectious Diseases, University of California San Diego, La Jolla, California, USA
| | - A L Landay
- Department of Immunology-Microbiology, Rush University Medical Center, Chicago, Illinois, USA
| | - M C McManus
- Department of Pathology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - C E Robertson
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- University of Colorado Microbiome Research Consortium, Aurora, Colorado, USA
| | - D N Frank
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- University of Colorado Microbiome Research Consortium, Aurora, Colorado, USA
| | - M D McCarter
- Department of Surgery, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - C C Wilson
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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Abstract
The historical development, pharmacology, pharmacodynamics, pharmacokinetics, clinical applications, pharmacologic basis for selection, adverse effects, and cost of neuromuscular blockers (NMBs) are discussed. The first NMB to be used was tubocurarine. During neurotransmission, acetylcholine is synthesized, stored in vesicles at the neuromuscular junction, released into the synapse, and bound to nicotinic receptors in the muscle end plate. For muscle contraction to occur, the impulse generated in a neuron's cell body must create an action potential that is chemically transmitted across the synapse. The postsynaptic nicotinic receptor at the neuromuscular junction is the major site of action of depolarizing and nondepolarizing NMBs. All NMBs have the potential for cross-reactivity at other nicotinic and muscarinic sites. Drug interactions most commonly occur between NMBs and inhalation anesthetics, certain antimicrobials, calcium-channel blockers, and anticholinesterases. When selecting an NMB, an agent's onset and duration of action must be considered. NMBs can be used on a short-term or long-term basis. Apart from cost, the choice of an NMB is made on the basis of its adverse-reaction profile, pharmacokinetics, and indications for use. Monitoring tools, their use, the rationale for their use, and the interpretation of the results they provide are unique. The patterns of peripheral nerve stimulation vary and elicit different characteristics of nondepolarizing neuromuscular blockade. The effectiveness of reversal agents is proportional to the degree of blockade. The mechanism of action of anticholinesterases involves inhibition of acetylcholinesterase. The expensive NMBs should be conserved for use in surgery, while the cheaper, long-acting [corrected] agents should be used in the intensive care unit. An understanding of the pharmacology, pharmacodynamics, and pharmacokinetics of NMBs will help health care providers gain expertise in the selection and use of these agents.
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Affiliation(s)
- M C McManus
- School of Pharmacy, Bouve College of Health Sciences, Northeastern University, Boston, MA, USA.
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4
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Abstract
The historical development, pharmacology, pharmacodynamics, pharmacokinetics, clinical applications, pharmacologic basis for selection, adverse effects, and cost of neuromuscular blockers (NMBs) are discussed. The first NMB to be used was tubocurarine. During neurotransmission, acetylcholine is synthesized, stored in vesicles at the neuromuscular junction, released into the synapse, and bound to nicotinic receptors in the muscle end plate. For muscle contraction to occur, the impulse generated in a neuron's cell body must create an action potential that is chemically transmitted across the synapse. The postsynaptic nicotinic receptor at the neuromuscular junction is the major site of action of depolarizing and nondepolarizing NMBs. All NMBs have the potential for cross-reactivity at other nicotinic and muscarinic sites. Drug interactions most commonly occur between NMBs and inhalation anesthetics, certain antimicrobials, calcium-channel blockers, and anticholinesterases. When selecting an NMB, an agent's onset and duration of action must be considered. NMBs can be used on a short-term or long-term basis. Apart from cost, the choice of an NMB is made on the basis of its adverse-reaction profile, pharmacokinetics, and indications for use. Monitoring tools, their use, the rationale for their use, and the interpretation of the results they provide are unique. The patterns of peripheral nerve stimulation vary and elicit different characteristics of nondepolarizing neuromuscular blockade. The effectiveness of reversal agents is proportional to the degree of blockade. The mechanism of action of anticholinesterases involves inhibition of acetylcholinesterase. The expensive NMBs should be conserved for use in surgery, while the cheaper, long-acting [corrected] agents should be used in the intensive care unit. An understanding of the pharmacology, pharmacodynamics, and pharmacokinetics of NMBs will help health care providers gain expertise in the selection and use of these agents.
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Affiliation(s)
- M C McManus
- School of Pharmacy, Bouve College of Health Sciences, Northeastern University, Boston, MA, USA.
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Abstract
The mechanisms behind the development and spread of bacterial resistance to antimicrobial drugs are reviewed. The chief mechanisms by which antimicrobials act are interference with nucleic acid synthesis, binding to ribosomes, and inhibition of cell-wall synthesis and folate metabolism. Bacteria have evolved genetic and biochemical ways of resisting these antimicrobial actions. Genetic mechanisms include mutation and acquisition of new DNA. Bacteria resist antimicrobials biochemically by inactivating the drugs with beta-lactamases, acetylases, adenylases, and phosphorylases; reducing drug access sites of action by virtue of membrane characteristics; altering the drug target so that the antimicrobial no longer binds to it; bypassing the drug's metabolism; and developing tolerance. Enterococcal and staphylococcal resistance mechanisms are of particular importance clinically. There are three types of enterococcal resistance: (1) intrinsic resistance to aminoglycosides, aztreonam, cephalosporins, clindamycin, imipenem, penicillin, and trimethoprim-sulfamethoxazole, (2) tolerance to all cell-wall-active antimicrobials, and (3) acquired resistance to penicillin, aminoglycosides, chloramphenicol, erythromycin, tetracycline, and vancomycin. Staphylococcal resistance to penicillins is expressed as beta-lactamase production, secretion of novel beta-lactamases, expression of novel penicillin-binding proteins (PBPs) to which penicillins bind poorly, and increased production of or altered affinity to existing PBPs. Of great concern is whether newly described glycopeptide resistance can be transferred clinically from enterococci to staphylococci. Vancomycin use is discouraged to limit the spread of glycopeptide resistance. Many mechanisms are responsible for the development and spread of antimicrobial resistance.
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Affiliation(s)
- M C McManus
- Department of Pharmacy Services, Boston Veterans Affairs Medical Center, MA 02601, USA.
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McManus MC. Prudent selection of antimicrobials for neonatal sepsis. Am J Health Syst Pharm 1996; 53:1956-60. [PMID: 8862211 DOI: 10.1093/ajhp/53.16.1956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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Wallace RW, Tallant EA, McManus MC. Human platelet calmodulin-binding proteins: identification and Ca2+-dependent proteolysis upon platelet activation. Biochemistry 1987; 26:2766-73. [PMID: 3111525 DOI: 10.1021/bi00384a017] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Calmodulin-binding proteins have been identified in human platelets by using Western blotting techniques and 125I-calmodulin. Ten distinct proteins of 245, 225, 175, 150, 90, 82 (2), 60, and 41 (2) kilodaltons (kDa) bound 125I-calmodulin in a Ca2+-dependent manner; the binding was blocked by ethylene glycol bis(beta-aminoethyl ether)-N,N,N'N'-tetraacetic acid (EGTA), trifluoperazine, and nonradiolabeled calmodulin. Proteins of 225 and 90 kDa were labeled by antisera against myosin light chain kinase; 60- and 82-kDa proteins were labeled by antisera against the calmodulin-dependent phosphatase and caldesmon, respectively. The remaining calmodulin-binding proteins have not been identified. Calmodulin-binding proteins were degraded upon addition of Ca2+ to a platelet homogenate; the degradation could be blocked by either EGTA, leupeptin, or N-ethylmaleimide which suggests that the degradation was due to a Ca2+-dependent protease. Activation of intact platelets by thrombin, adenosine 5'-diphosphate, and collagen under conditions which promote platelet aggregation (i.e., stirring with extracellular Ca2+) also resulted in limited proteolysis of calmodulin-binding proteins including those labeled with antisera against myosin light chain kinase and the calmodulin-dependent phosphatase. Activation by the Ca2+ ionophores A23187 and ionomycin also promoted degradation of the calmodulin-binding proteins in the presence of extracellular Ca2+; however, degradation in response to the ionophores did not require stirring of the platelet suspension to promote aggregation. Many Ca2+/calmodulin-regulated enzymes are irreversibly activated in vitro by limited proteolysis. Our data indicate that limited proteolysis of Ca2+/calmodulin-regulated enzymes also occurs in the intact platelet and suggest that the proteolysis is triggered by an influx of extracellular Ca2+ associated with platelet aggregation.
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McManus MC, Barriere SL. Interaction between newer cephalosporins and Clinitest, Diastix, and Tes-Tape. Am J Hosp Pharm 1983; 40:1544-5. [PMID: 6624763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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