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Wilkinson AS, Walker KE, Ozolina L, Machníková R, Johnson AJ, Bhogal N, Pegg K. Integrity performance assessment of a closed system transfer device syringe adaptor lock as a terminal closure for Luer-Lock syringes. Eur J Hosp Pharm 2023; 31:50-56. [PMID: 35410874 PMCID: PMC10800267 DOI: 10.1136/ejhpharm-2021-003148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 03/29/2022] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVES To investigate the container closure integrity of a closed system transfer device syringe adaptor lock in combination with disposable Luer-Lock syringes as the terminal closure device. The UK National Health Service (NHS) Pharmaceutical Quality Assurance Committee (PQAC) requires syringe integrity data for final storage devices of aseptic products such as chemotherapy drugs when prepared in advance and stored before use, as is standard practice for dose banded drugs. The assessment comprised both physical and microbial integrity testing of the combination closed system/Luer-Lock syringe containers at syringe sizes of 1 mL, 20 mL, and 50 mL. METHODS Integrity testing was performed as described in the NHS Pharmaceutical Quality Assurance Committee yellow cover document, second edition 2013 'Protocols for the Integrity Testing of Syringes', with Chemfort (Simplivia, IL) syringe adaptor lock (SAL) devices as replacement for sterile blind hubs. Microbiological integrity was assessed according to method 1 part 1.4 using Brevundimonas diminuta at 32°C for up to 14 days of contact time. Two positive control devices per syringe size were tested using a blind hub cap as closure which was loosened before the test. Physical integrity was assessed using method 3 of the yellow cover document which is a dye intrusion method. Dye intrusion was assessed both visually and using a validated ultraviolet-visible spectrophotometer method. For each size/batch of test articles a positive control device (n=1) was assessed using a wire wrapped around the syringe plunger tip deliberately compromising integrity. Negative controls for each size (n=1) consisted of devices not immersed in methylene blue dye. RESULTS Chemfort syringe adaptor lock/Luer-Lock syringe combinations were shown to be: (1) free of microbiological contamination after 14 days of contact time (n=60); and (2) free of dye intrusion at all syringe sizes tested (n=61 in total). The data demonstrate 100% closure integrity of the final container system when the Chemfort syringe adaptor lock replaces the syringe hub as the terminal closure device. All positive control devices demonstrated system suitability as container integrity was compromised in all positive control tests. All negative controls were negative for microbial and dye intrusion. CONCLUSIONS Syringe adaptor lock components complied with the NHS Pharmaceutical Quality Assurance Committee yellow cover document syringe integrity requirements when used as the terminal closure of Luer-Lock disposable syringes from 1 mL up to 50 mL. Therefore, syringe adaptor lock (Chemfort) can be used as the terminal closure system for pre-filled syringes of chemotherapeutic drug products prepared in advance in UK NHS pharmacy technical services.
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Affiliation(s)
- Alan Shaun Wilkinson
- R&D, Biopharma Stability Testing Laboratory Ltd, Nottingham, Nottinghamshire, UK
| | - Kate E Walker
- R&D, Biopharma Stability Testing Laboratory Ltd, Nottingham, Nottinghamshire, UK
| | - Laima Ozolina
- R&D, Biopharma Stability Testing Laboratory Ltd, Nottingham, Nottinghamshire, UK
| | - Romana Machníková
- R&D, Biopharma Stability Testing Laboratory Ltd, Nottingham, Nottinghamshire, UK
| | - Andrew J Johnson
- R&D, Biopharma Stability Testing Laboratory Ltd, Nottingham, Nottinghamshire, UK
| | - Navneet Bhogal
- QA Pharmacy, University Hospitals of Derby and Burton NHS Foundation Trust, Derby, Derbyshire, UK
| | - Kate Pegg
- QA Pharmacy, University Hospitals of Derby and Burton NHS Foundation Trust, Derby, Derbyshire, UK
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Chamberlain T, Biskupek J, Skowron ST, Markevich AV, Kurasch S, Reimer O, Walker KE, Rance GA, Feng X, Müllen K, Turchanin A, Lebedeva MA, Majouga AG, Nenajdenko VG, Kaiser U, Besley E, Khlobystov AN. Stop-Frame Filming and Discovery of Reactions at the Single-Molecule Level by Transmission Electron Microscopy. ACS Nano 2017; 11:2509-2520. [PMID: 28191929 PMCID: PMC5371926 DOI: 10.1021/acsnano.6b08228] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 02/13/2017] [Indexed: 05/28/2023]
Abstract
We report an approach, named chemTEM, to follow chemical transformations at the single-molecule level with the electron beam of a transmission electron microscope (TEM) applied as both a tunable source of energy and a sub-angstrom imaging probe. Deposited on graphene, disk-shaped perchlorocoronene molecules are precluded from intermolecular interactions. This allows monomolecular transformations to be studied at the single-molecule level in real time and reveals chlorine elimination and reactive aryne formation as a key initial stage of multistep reactions initiated by the 80 keV e-beam. Under the same conditions, perchlorocoronene confined within a nanotube cavity, where the molecules are situated in very close proximity to each other, enables imaging of intermolecular reactions, starting with the Diels-Alder cycloaddition of a generated aryne, followed by rearrangement of the angular adduct to a planar polyaromatic structure and the formation of a perchlorinated zigzag nanoribbon of graphene as the final product. ChemTEM enables the entire process of polycondensation, including the formation of metastable intermediates, to be captured in a one-shot "movie". A molecule with a similar size and shape but with a different chemical composition, octathio[8]circulene, under the same conditions undergoes another type of polycondensation via thiyl biradical generation and subsequent reaction leading to polythiophene nanoribbons with irregular edges incorporating bridging sulfur atoms. Graphene or carbon nanotubes supporting the individual molecules during chemTEM studies ensure that the elastic interactions of the molecules with the e-beam are the dominant forces that initiate and drive the reactions we image. Our ab initio DFT calculations explicitly incorporating the e-beam in the theoretical model correlate with the chemTEM observations and give a mechanism for direct control not only of the type of the reaction but also of the reaction rate. Selection of the appropriate e-beam energy and control of the dose rate in chemTEM enabled imaging of reactions on a time frame commensurate with TEM image capture rates, revealing atomistic mechanisms of previously unknown processes.
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Affiliation(s)
- Thomas
W. Chamberlain
- School
of Chemistry, University of Nottingham, Nottingham NG7 2RD, United Kingdom
- Institute
of Process Research and Development, School of Chemistry, University of Leeds, Leeds LS2 9JT, United
Kingdom
| | - Johannes Biskupek
- Central
Facility of Electron Microscopy, Electron Microscopy Group of Materials
Science, University of Ulm, 89081 Ulm, Germany
| | - Stephen T. Skowron
- School
of Chemistry, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | | | - Simon Kurasch
- Central
Facility of Electron Microscopy, Electron Microscopy Group of Materials
Science, University of Ulm, 89081 Ulm, Germany
| | - Oliver Reimer
- Faculty
of Physics, University of Bielefeld, 33615 Bielefeld, Germany
| | - Kate E. Walker
- School
of Chemistry, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Graham A. Rance
- School
of Chemistry, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Xinliang Feng
- Center
for Advancing Electronics Dresden (cfaed) and Department of Chemistry
and Food Chemistry, Technische Universitaet
Dresden, 01069 Dresden, Germany
| | - Klaus Müllen
- Max Planck
Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Andrey Turchanin
- Institute
of Physical Chemistry, Friedrich Schiller
University Jena, Lessingstraße 10, 07743 Jena, Germany
| | - Maria A. Lebedeva
- School
of Chemistry, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Alexander G. Majouga
- Department
of Chemistry, Moscow M.V. Lomonosov State
University, Leninskiye Gory, Moscow 119992, Russia
| | - Valentin G. Nenajdenko
- Department
of Chemistry, Moscow M.V. Lomonosov State
University, Leninskiye Gory, Moscow 119992, Russia
| | - Ute Kaiser
- Central
Facility of Electron Microscopy, Electron Microscopy Group of Materials
Science, University of Ulm, 89081 Ulm, Germany
| | - Elena Besley
- School
of Chemistry, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Andrei N. Khlobystov
- School
of Chemistry, University of Nottingham, Nottingham NG7 2RD, United Kingdom
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Abstract
Background—
Although hypercholesterolemia is a well-established risk factor for coronary artery disease, little is known regarding its direct effects on cardiac function.
Methods and Results—
We examined the effects of cholesterol feeding (0.5%) on cardiac function in rabbits. After 10 weeks, both systolic shortening and diastolic relaxation rates were impaired without any change in aortic pressure or ventricular hypertrophy. However, sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA)-2 mRNA levels were reduced within 4 days after initiation of cholesterol feeding. After this effect, SERCA-2 protein and SERCA-mediated Ca uptake into sarcoplasmic reticulum vesicles were impaired, and the ratio of MHC-β to MHC-α mRNA increased 5-fold. Suppression of the SERCA-2 message correlated temporally with enrichment of the cardiac sarcolemma with cholesterol.
Conclusions—
These data demonstrate that dietary hypercholesterolemia induces a “cholesterol cardiomyopathy” characterized by systolic and diastolic dysfunction. These alterations were independent of vascular disease and demonstrate a dietary link to cardiac dysfunction.
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Affiliation(s)
- Y Huang
- Department of Surgery, Thomas Jefferson University College of Medicine, Philadelphia, Pa 19107, USA
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Walker KE, Moghaddame-Jafari S, Lockatell CV, Johnson D, Belas R. ZapA, the IgA-degrading metalloprotease of Proteus mirabilis, is a virulence factor expressed specifically in swarmer cells. Mol Microbiol 1999; 32:825-36. [PMID: 10361285 DOI: 10.1046/j.1365-2958.1999.01401.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The IgA-degrading metalloprotease, ZapA, of the urinary tract pathogen Proteus mirabilis is co-ordinately expressed along with other proteins and virulence factors during swarmer cell differentiation. In this communication, we have used zapA to monitor IgA protease expression during the differentiation of vegetative swimmer cells to fully differentiated swarmer cells. Northern blot analysis of wild-type cells and beta-galactosidase measurements using a zapA:lacZ fusion strain indicate that zapA is fully expressed only in differentiated swarmer cells. Moreover, the expression of zapA on nutrient agar medium is co-ordinately regulated in concert with the cycles of cellular differentiation, swarm migration and consolidation that produce the bull's-eye colonies typically associated with P. mirabilis. ZapA activity is not required for swarmer cell differentiation or swarming behaviour, as ZapA- strains produce wild-type colony patterns. ZapA- strains fail to degrade IgA and show decreased survival compared with the wild-type cells during infection in a mouse model of ascending urinary tract infection (UTI). These data underscore the importance of the P. mirabilis IgA-degrading metalloprotease in UTI. Analysis of the nucleotide sequences adjacent to zapA reveals four additional genes, zapE, zapB, zapC and zapD, which appear to possess functions required for ZapA activity and IgA proteolysis. Based on homology to other known proteins, these genes encode a second metalloprotease, ZapE, as well as a ZapA-specific ABC transporter system (ZapB, ZapC and ZapD). A model describing the function and interaction of each of these five proteins in the degradation of host IgA during UTI is presented.
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Affiliation(s)
- K E Walker
- Center of Marine Biotechnology, University of Maryland Biotechnology Institute, Suite 236 Columbus Center, 701 E. Pratt Street, Baltimore, MD 21202 USA
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Temple LM, Weiss AA, Walker KE, Barnes HJ, Christensen VL, Miyamoto DM, Shelton CB, Orndorff PE. Bordetella avium virulence measured in vivo and in vitro. Infect Immun 1998; 66:5244-51. [PMID: 9784529 PMCID: PMC108655 DOI: 10.1128/iai.66.11.5244-5251.1998] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/1998] [Accepted: 08/24/1998] [Indexed: 11/20/2022] Open
Abstract
Bordetella avium causes an upper-respiratory-tract disease called bordetellosis in birds. Bordetellosis shares many of the clinical and histopathological features of disease caused in mammals by Bordetella pertussis and Bordetella bronchiseptica. In this study we determined several parameters of infection in the domestic turkey, Meleagris galapavo, and compared these in vivo findings with an in vitro measure of adherence using turkey tracheal rings. In the in vivo experiments, we determined the effects of age, group size, infection duration, and interindividual spread of B. avium. Also, the effect of host genetic background on susceptibility was tested in the five major commercial turkey lines by infecting each with the parental B. avium strain and three B. avium insertion mutants. The mutant strains lacked either motility, the ability to agglutinate guinea pig erythrocytes, or the ability to produce dermonecrotic toxin. The susceptibilities of 1-day-old and 1-week-old turkeys to B. avium were the same, and challenge group size (5, 8, or 10 birds) had no effect upon the 50% infectious dose. Two weeks between inoculation and tracheal culture was optimal, since an avirulent mutant (unable to produce dermonecrotic toxin) persisted for a shorter time. Communicability of the B. avium parental strain between confined birds was modest, but a nonmotile mutant was less able to spread between birds. There were no host-associated differences in susceptibility to the parental strain and the three B. avium mutant strains just mentioned: in all turkey lines tested, the dermonecrotic toxin- and hemagglutination-negative mutants were avirulent whereas the nonmotile mutants showed no loss of virulence. Interestingly, the ability of a strain to cause disease in vivo correlated completely with its ability to adhere to ciliated tracheal cells in vitro.
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Affiliation(s)
- L M Temple
- Department of Biology, Drew University, Madison, New Jersey 07940, USA
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Cooling LL, Walker KE, Gille T, Koerner TA. Shiga toxin binds human platelets via globotriaosylceramide (Pk antigen) and a novel platelet glycosphingolipid. Infect Immun 1998; 66:4355-66. [PMID: 9712788 PMCID: PMC108526 DOI: 10.1128/iai.66.9.4355-4366.1998] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/1998] [Accepted: 06/26/1998] [Indexed: 11/20/2022] Open
Abstract
Hemolytic-uremic syndrome is a clinical syndrome characterized by acute renal failure, microangiopathic hemolytic anemia, and thrombocytopenia that often follows infection by Shiga toxin- or verotoxin-producing strains of Escherichia coli. Because thrombocytopenia and platelet activation are hallmark features of hemolytic-uremic syndrome, we examined the ability of Shiga toxin to bind platelets by flow cytometry and high-performance thin-layer chromatography (HPTLC) of isolated platelet glycosphingolipids. By HPTLC, Shiga toxin was shown to bind globotriaosylceramide (Gb3) and a minor platelet glycolipid with an Rf of 0.03, band 0.03. In a survey of 20 human tissues, band 0.03 was identified only in platelets. In individuals, band 0.03 was expressed by 20% of donors and was specifically associated with increased platelet Gb3 expression. Based on glycosidase digestion and epitope mapping, band 0.03 was hypothesized to represent a novel glycosphingolipid, IV3-beta-Galalpha1-4galactosylglobotetraosylceramide. Based on incidence, structure, and association with increased Gb3 expression, band 0.03 may represent the antithetical Luke blood group antigen. By flow cytometry, Shiga toxin bound human platelets, although the amount of Shiga toxin bound varied in donors. Differences in Shiga toxin binding to platelet membranes did not reflect differences in platelet Gb3 expression. In contrast, there was a loose association between Shiga toxin binding and decreasing forward scatter, suggesting that Shiga toxin and verotoxins bind more efficiently to smaller, older platelets. In summary, Shiga and Shiga-like toxins may bind platelets via specific glycosphingolipid receptors. Such binding may contribute to the thrombocytopenia, platelet activation, and microthrombus formation observed in hemolytic-uremic syndrome.
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Affiliation(s)
- L L Cooling
- Department of Pathology, SUNY Health Science Center at Syracuse, Syracuse, New York, USA
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7
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Cooling LL, Zhang DS, Walker KE, Koerner TA. Detection in human blood platelets of sialyl Lewis X gangliosides, potential ligands for CD62 and other selectins. Glycobiology 1995; 5:571-81. [PMID: 8563144 DOI: 10.1093/glycob/5.6.571] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Activated platelets are known to express P-selectin, a lectin-like adhesion receptor (CD62), through which they bind to sialyl Lewis X (sLex) ligands displayed on the membranes of leukocytes. To determine whether direct platelet-platelet interactions via P-selectin/sLex interactions are also possible, we have examined the ganglioside extract of human blood platelets for the presence of sLex ligands. Using the sensitive method of high-performance thin-layer chromatography (HPTLC)-immunostaining with the monoclonal antibody (mAb) CSLEX or with sialidase followed by mAbs MC480 or PM81, eight sLex bands were demonstrated at Rf 0.01, 0.03, 0.05, 0.06, 0.08, 0.10, 0.14 and 0.21 in the solvent 45:55:10 chloroform-methanol-aqueous 0.02% CaCl2. The sensitivity of all eight bands to sialidase or endoglycoceramidase confirmed that they were gangliosides. Comparison of the HPTLC mobilities and densities of platelet bands with those from five other human tissues (granulocytes, monoblasts, kidney, aortic endothelium and erythrocytes) in three different solvents revealed three major bands associated with platelets: 3 (Rf0.03), 6 (0.08) and 14 (0.21). Platelet bands were demonstrated not to have resulted from granulocyte contamination. Partial purification of platelet sLex gangliosides by high-performance liquid chromatography and their reaction with 14 oligosaccharide-specific mAbs (FH4, FH5, LM112-161, LM119-181, A5, 1B2, BR55-2, BE2, ES4, MC631, MH04, SH34, P001 and MC813-70) revealed that band 6 is a multifucosylated neolacto ganglioside and band 14 is a branched, disialo neolacto fucoganglioside. Platelet band 3 combined the features of both bands 6 and 14, and reacted differently than granulocyte band 3. These partial structures resemble gangliosides associated with adhesion in other cell systems. It is concluded that platelets express tissue-specific sLex gangliosides (sLex ligands). Thus, it is possible that platelet-platelet binding may be mediated at least partially through P-selectin/sLex interactions, especially after platelet activation.
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Affiliation(s)
- L L Cooling
- Department of Pathology, University of Iowa College of Medicine, Iowa City 52242-1182, USA
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8
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Chengalath P, Walker KE. Utilization management in Alberta's new funding environment. Physician Exec 1995; 21:29-33. [PMID: 10140903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Although physicians have the greatest influence on the resource utilization of hospital patients, Canadian hospitals have not been too successful in bringing physicians into the resource planning and decision-making processes. This is because most hospitals have been unable to provide the information needed by physicians to participate in resource management in a meaningful way. With the introduction of a new system in the Canadian Province of Alberta that fundamentally changes the way hospitals are funded, it has become even more important to involve medical staffs in the utilization management process. This article describes the new funding system and highlights some of the ways in which Wetaskiwin Health Care Centre has leveraged information technology to support the utilization management process in this new environment.
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Abstract
All members of the genus Bordetella and Pasteurella multocida (a gram-negative bacillus genetically unrelated to Bordetella spp., yet often sharing the same ecological niche) produce a dermonecrotic toxin (DNT). The amount of toxin produced and the time required for appearance of the lesions are identical for Bordetella pertussis, B. parapertussis, and B. bronchiseptica but different for P. multocida and B. avium. DNT has been reported to act by promoting vasoconstriction; however, vasoactive compounds (verapamil, prazosin, hydralazine, tolazoline, or isoxsuprine) are able to reverse the action of the toxin only slightly. Vasoconstrictors (atropine, serotonin, epinephrine, or endothelin) did not produce DNT-like lesions. We have characterized a region of DNA essential for DNT expression. We have determined by Southern analysis that the restriction map of the DNT gene is nearly identical in B. pertussis, B. parapertussis, and B. bronchiseptica, but the sequences are not present in toxigenic B. avium and P. multocida strains. A gentamicin resistance-origin of transfer cassette cloned into a 1.8-kb NotI-BamHI fragment results in constructs which can be mobilized and recombined into the Bordetella chromosome, rendering the resultant B. pertussis, B. parapertussis, and B. bronchiseptica strains negative for DNT. A 5-kb BamHI-ApaI fragment from the B. pertussis chromosome was sequenced and revealed homology to the Escherichia coli CNF1 (cytotoxic necrotizing factor 1) toxin.
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Affiliation(s)
- K E Walker
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati, Ohio 45267
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Abstract
OBJECTIVE Action potential duration of senescent rat ventricular myocytes is longer than in young adults. The aim of the study was to determine whether age related changes in L-type calcium current (ICa), transient outward potassium current (ITO), and inwardly rectifying potassium current (IK1) are involved in the prolongation of the early (ICa, ITO) and late (IK1) portions of the rat action potential plateau. METHODS Whole cell voltage clamp techniques were used to study these currents in ventricular myocytes isolated from young (2-3 months), middle aged (8-9 months), and senescent (24-25 months) rats. RESULTS There were no differences in the magnitude of ICa among age groups once currents were normalised for capacitative surface area. The voltage dependence of ICa activation and steady state inactivation in the three age groups was also similar. At test potentials of 0 and +10 mV, there was a significant (p < or = 0.05) slowing in the time course of inactivation of ICa; the time constants of inactivation increased with age [young v old in ms(SEM): 0 mV, 22.2(2.2) v 38.0(5.0) (slow); +10 mV, 8.0(2.0) v 15.6(2.0) (fast)]. With internal EGTA to buffer intracellular Ca2+, no significant age related differences in action potential duration or the time course of ICa inactivation were observed. There was an age associated decrease in peak ITO density in the old (n = 25) compared to the young (n = 25) cell group (p < 0.05). The only age associated change in the kinetic properties of ITO was a small but consistent slowing in the time constants of inactivation at most test voltages measured, with significance occurring at 0 mV in the slow (tau 2) component. CONCLUSIONS ICa density is maintained in senescence; ICa inactivation, however, is slowed. Age related differences in action potential duration and ICa inactivation were reduced by buffering intracellular Ca2+. ITO channels appear to retain normal function through the aging process but overall there is a reduced channel density. The age associated changes in these currents should contribute to prolongation of action potential duration of the early plateau phase seen in the senescent rat.
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Affiliation(s)
- K E Walker
- Department of Medicine, Medical College of Pennsylvania, Philadelphia
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Weiss AA, Melton AR, Walker KE, Andraos-Selim C, Meidl JJ. Use of the promoter fusion transposon Tn5 lac to identify mutations in Bordetella pertussis vir-regulated genes. Infect Immun 1989; 57:2674-82. [PMID: 2569447 PMCID: PMC313511 DOI: 10.1128/iai.57.9.2674-2682.1989] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Mutants of Bordetella pertussis deficient in virulence-associated factors were identified by using the transposon Tn5 lac. Tn5 lac is a derivative of Tn5 which generates promoter fusions for beta-galactosidase. Tn5 lac insertions in the vir-regulated genes of B. pertussis were identified by selecting for kanamycin-resistant mutants that expressed beta-galactosidase when the vir-regulated genes were expressed but not when the vir-regulated genes were turned off. Fourteen different mutations in vir-regulated genes were identified. Two mutants were deficient in the production of the filamentous hemagglutinin, two mutants were deficient in the production of adenylate cyclase toxin and hemolysin, and one mutant was deficient in the production of dermonecrotic toxin. One insertion mapped adjacent to the pertussis toxin gene, but the mutant produced pertussis toxin. The phenotypes of the remaining eight mutants were not determined, but the mutants did not appear to be deficient in the production of the 69,000-dalton outer membrane protein (agglutinogen 3) or the capsule. Screening for mutations in either of the fimbrial genes proved to be problematic since the parental strain was found to switch from a fimbriated to a nonfimbriated state at a high frequency, which was suggestive of the metastable expression of pili in other bacteria. We used Southern blot analysis with a 30-mer specific for the fimbrial sequences. No bands with the predicted increase in size due to the 12 kilobases from Tn5 lac were observed, which suggests that none of these genes were mutated. Southern blot analysis also revealed that seven of the eight unidentified mutations mapped to different restriction fragments, which suggests that they could be deficient in as many as seven different genes.
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Affiliation(s)
- A A Weiss
- Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond 23298
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12
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Walker KE. Tampa General Hospital: planning for its major move. Hosp Mater Manage Q 1986; 8:15-9. [PMID: 10277523] [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: 02/12/2023]
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Ho BT, Gardner PM, Englert LF, Walker KE. Effects of aromatic aldehydes on O-methylation of dopamine and norepinephrine in vitro. J Pharm Sci 1974; 63:1261-4. [PMID: 4859299 DOI: 10.1002/jps.2600630820] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Ho BT, Gardner PM, Pong SF, Walker KE. A new peripheral monoamine oxidase inhibitor: 2,9-dimethyl-beta-carbolinium iodide. Experientia 1973; 29:527-9. [PMID: 4730276 DOI: 10.1007/bf01926643] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Ho BT, Taylor D, Walker KE, McIsaac WM. The mode of action of 6-methoxy-1,2,3,4-tetrahydro- -carboline on brain serotonin. Can J Biochem 1973; 51:482-5. [PMID: 4540471 DOI: 10.1139/o73-057] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
6-Methoxy-1,2,3,4-tetrahydro-β-carboline (6-MeO-THBC), which specifically elevates serotonin in the brain, exerted no significant effects on mouse brain monoamine oxidase, rat brain tryptophan hydroxylase, and rat liver tryptophan pyrrolase. There was a marked activation of rat plasma and liver 5-hydroxytryptophan decarboxylase and a concomitant increase of serotonin levels in the two tissues. 6-MeO-THBC did not alter the endogenous tryptophan levels in rat plasma and brain. A significant facilitation of the uptake of [3-14C]-5-hydroxytryptophan was observed in brains of mice treated with 6-MeO-THBC. The possibility that the increased serotonin was derived from 6-MeO-THBC itself was ruled out.
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Ho BT, Li KC, Walker KE, Tansey LW, Kralik PM, McIsaac WM. Inhibitors of monoamine oxidase. VI. Effects of substitution on inhibitory activity of 6(or 8)-substituted beta-carbolines. J Pharm Sci 1970; 59:1445-8. [PMID: 5471952 DOI: 10.1002/jps.2600591016] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Ho BT, McIsaac WM, An R, Tansey LW, Walker KE, Englert LF, Noel MB. Analogs of alpha-methylphenethylamine (amphetamine). I. Synthesis and pharmacological activity of some methoxy and/or methyl analogs. J Med Chem 1970; 13:26-30. [PMID: 5412110 DOI: 10.1021/jm00295a007] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Ho BT, McIsaac MW, An R, Harris RT, Walker KE, Kralik PM, Airaksinen MM. Biological activities of some 5-substituted N,N-dimethyltryptamines, alpha-methyltryptamines, and gramines. Psychopharmacology (Berl) 1970; 16:385-94. [PMID: 5435874 DOI: 10.1007/bf00404849] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Ho BT, Fritchie GE, Kralik PM, Tansey LW, Walker KE, McIsaac WM. Inhibitors of monoamine oxidase. V. Effect of substitution on the transport of tetrahydro-beta-carboline analogs to mouse brain. J Pharm Sci 1969; 58:1423-5. [PMID: 5349767 DOI: 10.1002/jps.2600581132] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Ho BT, McIsaac WM, Walker KE. Inhibitors of monoamine oxidase. II. Syntheses of some N-2(9)-substituted tetrahydro-beta-carbolines and evaluation of their inhibitory activities. J Pharm Sci 1968; 57:1364-9. [PMID: 5677342 DOI: 10.1002/jps.2600570819] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Ho BT, McIsaac WM, Walker KE, Estevez V. Inhibitors of monoamine oxidase. Influence of methyl substitution on the inhibitory activity of beta-carbolines. J Pharm Sci 1968; 57:269-74. [PMID: 5641670 DOI: 10.1002/jps.2600570205] [Citation(s) in RCA: 94] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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