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Dufresne SKY, Zhdanovich S, Michiardi M, Guislain BG, Zonno M, Mazzotti V, O'Brien L, Kung S, Levy G, Mills AK, Boschini F, Jones DJ, Damascelli A. A versatile laser-based apparatus for time-resolved ARPES with micro-scale spatial resolution. Rev Sci Instrum 2024; 95:033907. [PMID: 38517258 DOI: 10.1063/5.0176170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 02/28/2024] [Indexed: 03/23/2024]
Abstract
We present the development of a versatile apparatus for 6.2 eV laser-based time and angle-resolved photoemission spectroscopy with micrometer spatial resolution (time-resolved μ-ARPES). With a combination of tunable spatial resolution down to ∼11 μm, high energy resolution (∼11 meV), near-transform-limited temporal resolution (∼280 fs), and tunable 1.55 eV pump fluence up to 3 mJ/cm2, this time-resolved μ-ARPES system enables the measurement of ultrafast electron dynamics in exfoliated and inhomogeneous materials. We demonstrate the performance of our system by correlating the spectral broadening of the topological surface state of Bi2Se3 with the spatial dimension of the probe pulse, as well as resolving the spatial inhomogeneity contribution to the observed spectral broadening. Finally, after in situ exfoliation, we performed time-resolved μ-ARPES on a ∼30 μm flake of transition metal dichalcogenide WTe2, thus demonstrating the ability to access ultrafast electron dynamics with momentum resolution on micro-exfoliated materials.
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Affiliation(s)
- S K Y Dufresne
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - S Zhdanovich
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - M Michiardi
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - B G Guislain
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - M Zonno
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - V Mazzotti
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - L O'Brien
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - S Kung
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - G Levy
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - A K Mills
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - F Boschini
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, Varennes, Québec J3X 1S2, Canada
| | - D J Jones
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - A Damascelli
- Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
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Mills AK, Zhdanovich S, Na MX, Boschini F, Razzoli E, Michiardi M, Sheyerman A, Schneider M, Hammond TJ, Süss V, Felser C, Damascelli A, Jones DJ. Cavity-enhanced high harmonic generation for extreme ultraviolet time- and angle-resolved photoemission spectroscopy. Rev Sci Instrum 2019; 90:083001. [PMID: 31472611 DOI: 10.1063/1.5090507] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 07/14/2019] [Indexed: 06/10/2023]
Abstract
With its direct correspondence to electronic structure, angle-resolved photoemission spectroscopy (ARPES) is a ubiquitous tool for the study of solids. When extended to the temporal domain, time-resolved (TR)-ARPES offers the potential to move beyond equilibrium properties, exploring both the unoccupied electronic structure as well as its dynamical response under ultrafast perturbation. Historically, ultrafast extreme ultraviolet sources employing high-order harmonic generation (HHG) have required compromises that make it challenging to achieve a high energy resolution-which is highly desirable for many TR-ARPES studies-while producing high photon energies and a high photon flux. We address this challenge by performing HHG inside a femtosecond enhancement cavity, realizing a practical source for TR-ARPES that achieves a flux of over 1011 photons/s delivered to the sample, operates over a range of 8-40 eV with a repetition rate of 60 MHz. This source enables TR-ARPES studies with a temporal and energy resolution of 190 fs and 22 meV, respectively. To characterize the system, we perform ARPES measurements of polycrystalline Au and MoTe2, as well as TR-ARPES studies on graphite.
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Affiliation(s)
- A K Mills
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - S Zhdanovich
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - M X Na
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - F Boschini
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - E Razzoli
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - M Michiardi
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - A Sheyerman
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - M Schneider
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - T J Hammond
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - V Süss
- Max Planck Institute for Chemical Physics of Solids, 01187 Dresden, Germany
| | - C Felser
- Max Planck Institute for Chemical Physics of Solids, 01187 Dresden, Germany
| | - A Damascelli
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - D J Jones
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
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Boschini F, da Silva Neto EH, Razzoli E, Zonno M, Peli S, Day RP, Michiardi M, Schneider M, Zwartsenberg B, Nigge P, Zhong RD, Schneeloch J, Gu GD, Zhdanovich S, Mills AK, Levy G, Jones DJ, Giannetti C, Damascelli A. Collapse of superconductivity in cuprates via ultrafast quenching of phase coherence. Nat Mater 2018; 17:416-420. [PMID: 29610487 DOI: 10.1038/s41563-018-0045-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 02/23/2018] [Indexed: 05/26/2023]
Abstract
The possibility of driving phase transitions in low-density condensates through the loss of phase coherence alone has far-reaching implications for the study of quantum phases of matter. This has inspired the development of tools to control and explore the collective properties of condensate phases via phase fluctuations. Electrically gated oxide interfaces1,2, ultracold Fermi atoms3,4 and cuprate superconductors5,6, which are characterized by an intrinsically small phase stiffness, are paradigmatic examples where these tools are having a dramatic impact. Here we use light pulses shorter than the internal thermalization time to drive and probe the phase fragility of the Bi2Sr2CaCu2O8+δ cuprate superconductor, completely melting the superconducting condensate without affecting the pairing strength. The resulting ultrafast dynamics of phase fluctuations and charge excitations are captured and disentangled by time-resolved photoemission spectroscopy. This work demonstrates the dominant role of phase coherence in the superconductor-to-normal state phase transition and offers a benchmark for non-equilibrium spectroscopic investigations of the cuprate phase diagram.
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Affiliation(s)
- F Boschini
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada.
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada.
| | - E H da Silva Neto
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada
- Max Planck Institute for Solid State Research, Stuttgart, Germany
- Department of Physics, University of California, Davis, CA, USA
| | - E Razzoli
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada
| | - M Zonno
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada
| | - S Peli
- Department of Mathematics and Physics, Università Cattolica del Sacro Cuore, Brescia, Italy
- Interdisciplinary Laboratories for Advanced Materials Physics (ILAMP), Università Cattolica del Sacro Cuore, Brescia, Italy
| | - R P Day
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada
| | - M Michiardi
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - M Schneider
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada
| | - B Zwartsenberg
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada
| | - P Nigge
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada
| | - R D Zhong
- Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY, USA
| | - J Schneeloch
- Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY, USA
- Department of Physics & Astronomy, Stony Brook University, Stony Brook, NY, USA
| | - G D Gu
- Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY, USA
| | - S Zhdanovich
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada
| | - A K Mills
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada
| | - G Levy
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada
| | - D J Jones
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada
| | - C Giannetti
- Department of Mathematics and Physics, Università Cattolica del Sacro Cuore, Brescia, Italy
- Interdisciplinary Laboratories for Advanced Materials Physics (ILAMP), Università Cattolica del Sacro Cuore, Brescia, Italy
| | - A Damascelli
- Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada.
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, Canada.
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Scott A, Morris K, Butler J, Mills AK, Kennedy GA. Treatment of aplastic anaemia with lower-dose anti-thymocyte globulin produces similar response rates and survival as per standard dose anti-thymocyte globulin schedules. Intern Med J 2016; 46:1198-1203. [PMID: 27404498 DOI: 10.1111/imj.13175] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Revised: 05/30/2016] [Accepted: 06/26/2016] [Indexed: 11/29/2022]
Abstract
BACKGROUND Aplastic anaemia (AA) is a rare acquired bone marrow failure syndrome resulting from the immune-mediated destruction of haemopoietic stem cells. For adults in whom first-line haemopoietic progenitor cell transplantation is not feasible, combination anti-thymocyte globulin (ATGAM) plus cyclosporine A is standard therapy; however, there are minimal data available regarding the optimal ATGAM dosage in terms of efficacy and survival. AIMS Our institutions have historically used different dosing protocols of ATGAM in the treatment of AA. We aimed to review the outcome of AA patients treated with these protocols and compare them to the published literature. METHODS We conducted a retrospective study of 31 adults who received first-line ATGAM for AA and compared response rates and survival between cohorts who received standard (40 mg/kg/day D1-4) versus lower-dose (15 mg/kg/day D1-5) ATGAM schedules. RESULTS There were similar rates of response (64 vs 71%, P = 1.0), relapse (33 vs 33%, P = 1.0), transformation (14 vs 24%, P = 0.66) or infection (43 vs 47%, P = 1.0), respectively, between standard and lower-dose cohorts. At a median follow up of 24 months, there was no statistical difference between standard and lower-dose cohorts in either event-free (42.2 vs 64.7%, P = 0.91) or overall survival (73.1 vs 88.2%, P = 0.75). CONCLUSION Our experience suggests that lower-dose ATGAM at 15 mg/kg/day D1-5 as treatment of AA produces similar responses and outcomes as per standard-dose ATGAM schedules. Prospective trials comparing ATGAM dose schedules in AA are warranted.
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Affiliation(s)
- A Scott
- Department of Cancer Care Services, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia. .,Department of Haematology, Pathology Queensland, Brisbane, Queensland, Australia. .,School of Medicine, The University of Queensland, Brisbane, Queensland, Australia.
| | - K Morris
- Department of Cancer Care Services, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - J Butler
- Department of Cancer Care Services, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - A K Mills
- Division of Cancer Services, Princess Alexandra Hospital, Brisbane, Queensland, Australia
| | - G A Kennedy
- Department of Cancer Care Services, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia.,School of Medicine, The University of Queensland, Brisbane, Queensland, Australia
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Huang L, Mills AK, Zhao Y, Jones DJ, Tang S. Miniature fiber-optic multiphoton microscopy system using frequency-doubled femtosecond Er-doped fiber laser. Biomed Opt Express 2016; 7:1948-56. [PMID: 27231633 PMCID: PMC4871093 DOI: 10.1364/boe.7.001948] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 04/05/2016] [Accepted: 04/06/2016] [Indexed: 05/08/2023]
Abstract
We report on a miniature fiber-optic multiphoton microscopy (MPM) system based on a frequency-doubled femtosecond Er-doped fiber laser. The femtosecond pulses from the laser source are delivered to the miniature fiber-optic probe at 1.58 µm wavelength, where a standard single mode fiber is used for delivery without the need of free-space dispersion compensation components. The beam is frequency-doubled inside the probe by a periodically poled MgO:LiNbO3 crystal. Frequency-doubled pulses at 786 nm with a maximum power of 80 mW and a pulsewidth of 150 fs are obtained and applied to excite intrinsic signals from tissues. A MEMS scanner, a miniature objective, and a multimode collection fiber are further used to make the probe compact. The miniature fiber-optic MPM system is highly portable and robust. Ex vivo multiphoton imaging of mammalian skins demonstrates the capability of the system in imaging biological tissues. The results show that the miniature fiber-optic MPM system using frequency-doubled femtosecond fiber laser can potentially bring the MPM imaging for clinical applications.
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Affiliation(s)
- Lin Huang
- Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, V6T 1Z4, Canada
| | - Arthur K. Mills
- Department of Physics & Astronomy, University of British Columbia, Vancouver, V6T 1Z4, Canada
| | - Yuan Zhao
- Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, V6T 1Z4, Canada
| | - David J. Jones
- Department of Physics & Astronomy, University of British Columbia, Vancouver, V6T 1Z4, Canada
| | - Shuo Tang
- Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, V6T 1Z4, Canada
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Ellis M, Mills AK. Successful maintenance of molecular remission in chronic myelogenous leukaemia during pregnancy with transition from imatinib to pegylated interferon. Intern Med J 2015; 45:358-9. [PMID: 25735582 DOI: 10.1111/imj.12687] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 10/21/2014] [Indexed: 01/28/2023]
Affiliation(s)
- M Ellis
- Department of Cancer Services, Princess Alexandra Hospital, Brisbane, Queensland, Australia
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Mills AK, Zhdanovich S, Sheyerman A, Levy G, Damascelli A, Jones DJ. An XUV source using a femtosecond enhancement cavity for photoemission spectroscopy. ACTA ACUST UNITED AC 2015. [DOI: 10.1117/12.2184547] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Hammond TJ, Mills AK, Jones DJ. Near-threshold harmonics from a femtosecond enhancement cavity-based EUV source: effects of multiple quantum pathways on spatial profile and yield. Opt Express 2011; 19:24871-24883. [PMID: 22273880 DOI: 10.1364/oe.19.024871] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We investigate the photon flux and far-field spatial profiles for near-threshold harmonics produced with a 66 MHz femtosecond enhancement cavity-based EUV source operating in the tight-focus regime. The effects of multiple quantum pathways in the far-field spatial profile and harmonic yield show a strong dependence on gas jet dynamics, particularly nozzle diameter and position. This simple system, consisting of only a 700 mW Ti:Sapphire oscillator and an enhancement cavity produces harmonics up to 20 eV with an estimated 30-100 μW of power (intracavity) and > 1μW (measured) of power spectrally-resolved and out-coupled from the cavity. While this power is already suitable for applications, a quantum mechanical model of the system indicates substantial improvements should be possible with technical upgrades.
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Affiliation(s)
- T J Hammond
- Department of Physics and Astronomy, University of British Columbia,Vancouver, British Columbia, Canada
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Abstract
We present a simple and quick, yet accurate method to measure the dispersion of high finesse optical cavities. By exciting the cavity with a femtosecond frequency comb and measuring the resonance condition as a function of optical frequency, the cavity's dispersion can be determined with minimal uncertainty. Measurement results are presented from an evacuated reference cavity with low group delay dispersion as well as several differential, intra-cavity measurements of well known optical materials demonstrating the dynamic range and accuracy of this technique.
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Affiliation(s)
- T J Hammond
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
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Morris KL, Tate JR, Gill D, Kennedy G, Wellwood J, Marlton P, Bird R, Mills AK, Mollee P. Diagnostic and prognostic utility of the serum free light chain assay in patients with AL amyloidosis. Intern Med J 2007; 37:456-63. [PMID: 17547724 DOI: 10.1111/j.1445-5994.2007.01368.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Organ dysfunction in AL amyloidosis is related to the production and deposition of amyloidogenic monoclonal light chains. These pathological light chains can now be quantified using the recently developed serum free light chain assay. METHODS We retrospectively reviewed 31 patients with AL amyloidosis to determine the frequency of abnormal free light chain assay results at diagnosis and whether changes in the serum free light chain assay predict outcome after therapy. RESULTS An abnormal free light chain assay was found in 30 of 31 patients (97%) at the time of diagnosis. In the subset of our patients who received treatment for AL amyloidosis, a >50% reduction of the pathological free light chain following treatment was shown to predict improved overall survival. In our series of analyses, achievement of greater magnitudes of reduction of the free light chain result did not appear to provide additional prognostic information, nor did the baseline free light chain result predict outcome. CONCLUSION Our findings support the use of the free light chain assay in the diagnostic work-up of patients with suspected AL amyloidosis, and also as a sensitive biomarker of response to therapy.
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Affiliation(s)
- K L Morris
- Department of Clinical and Laboratory Haematology, Queensland Health Pathology Service, Princess Alexandra Hospital, Woolloongabba, Queensland, Australia.
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Burry JS, Coulson HF, Esser I, Marti V, Melling SJ, Rawlings AV, Roberts G, Mills AK. Erroneous gender differences in axillary skin surface/sweat pH. Int J Cosmet Sci 2001; 23:99-107. [DOI: 10.1046/j.1467-2494.2001.00085.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Mills AK, Wright SJ, Taylor KM, McCormack JG. Hypercalcaemia caused by Pneumocystis carinii pneumonia while in leukaemic remission. Aust N Z J Med 1999; 29:102-3. [PMID: 10200829 DOI: 10.1111/j.1445-5994.1999.tb01604.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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13
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Mills AK, Taylor KM, Wright SJ, Bunce I, Eliadis P, Brigden MC, Seeley G, Bashford J, Olsen T, Rentoul A, Kelly C. Efficacy, safety and tolerability of anagrelide in the treatment of essential thrombocythaemia. Aust N Z J Med 1999; 29:29-35. [PMID: 10200810 DOI: 10.1111/j.1445-5994.1999.tb01585.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND Essential thrombocythaemia (ET) has an associated risk of thrombotic and haemorrhagic complications, which can be minimised by control of the platelet count. Anagrelide selectively lowers the platelet count, however, there is little Australasian experience with its use and scant data on symptom control. AIMS To evaluate the efficacy of anagrelide for platelet reduction and symptom control in a broad cohort of patients with well-defined ET, and to determine the safety and tolerability in such a population. METHODS Seventeen patients with ET and a platelet count > 600 x 10(9)/L were prospectively enrolled. The evaluable four males and 12 females with a median age of 58 years (range 14-79) included ten patients (63%) previously treated with two or more agents and 12 patients (75%) who had failed other therapies. The median follow-up was seven months (range 15 days to 36 months). RESULTS Anagrelide, in an average dose of 1.9 mg/day, reduced the platelet count from a mean of 728 x 10(9)/L (95% CI 611-845 x 10(9)/L) to 412 x 10(9)/L (95% CI 319-504 x 10(9)/L) (p < 0.001) and maintained it at this level. Fourteen patients (88%) had a platelet reduction to < 600 x 10(9)/L. All symptomatic patients had improvement in symptoms attributable to thrombocythaemia. There were three haemorrhagic and three thrombotic episodes in a total of three patients (19%), including one death from an intracerebral haemorrhage. Six patients (37%) were removed from therapy due to toxicity after a median of 151 days. Side effects included palpitations, abdominal pain and cough. CONCLUSIONS Anagrelide is efficacious and safe in ET, both for platelet and symptom control. Minor side effects are common, however, tend to occur early and resolve spontaneously in most cases.
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Affiliation(s)
- A K Mills
- Mater Hospital, Brisbane, Qld, Australia
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14
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Verrier RL, Mills AK, Skornik WA. Acute effects of carbon monoxide on cardiac electrical stability. Res Rep Health Eff Inst 1990:1-14. [PMID: 2291816] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The objective of this project was to determine the effects of acute carbon monoxide exposure on cardiac electrical stability. To obtain a comprehensive assessment, diverse biological models were employed. These involved cardiac electrical testing in the normal and ischemic heart in anesthetized and conscious dogs. The experimental plan was designed both to examine the direct effects of carbon monoxide exposure on the myocardium and to evaluate possible indirect influences through alterations in platelet aggregability or changes in central nervous system activity in the conscious animal. Our results indicate that exposure to relatively high levels of carbon monoxide, leading to carboxyhemoglobin concentrations of up to 20 percent, is without significant effect on ventricular electrical stability. This appears to be the case in the acutely ischemic heart as well as in the normal heart. It is important to note that the total exposure period was in the range of 90 to 124 minutes. The possibility that longer periods of exposure or exacerbation from nicotine in cigarette smoke could have a deleterious effect cannot be excluded. We also examined whether or not alterations in platelet aggregability due to carbon monoxide exposure could be a predisposing factor for cardiac arrhythmias. A model involving partial coronary artery stenosis was used to simulate the conditions under which platelet plugs could lead to myocardial ischemia and life-threatening arrhythmias. We found no changes either in the cycle frequency of coronary blood flow oscillations or in platelet aggregability during carbon monoxide exposure. Thus, carbon monoxide exposure does not appear to alter platelet aggregability or its effect on coronary blood flow during stenosis. In the final series of experiments, we examined the effects of carbon monoxide exposure in the conscious state. The rationale was to take into consideration possible adverse consequences mediated by the central nervous system. We found no adverse effects on cardiac excitable properties in response to either a 2-hour or 24-hour-exposure paradigm. This appears to argue against major deleterious influences of carbon monoxide exposure as a result of direct myocardial actions or indirect actions mediated through effects on central nervous system activity.
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Affiliation(s)
- R L Verrier
- Department of Pharmacology, Georgetown University Medical Center, Washington, DC 20007
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Dresner DL, Feinstein R, Mills AK. LACK OF PROLONGED RECOVERY DESPITE POTENTIATED ONSET OF MIXED ATRACURIUM AND VECURONIUM BLOCKADE. Anesth Analg 1990. [DOI: 10.1213/00000539-199002001-00089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Abstract
1. The effect of body surface area (BSA) burn injury on neuromuscular pharmacodynamics of vecuronium was evaluated. 2. The neuromuscular responses of 15 burned children were compared with those in five controls. 3. The effective dose for 50% suppression of twitch tension (ED50) was 34 micrograms kg-1 for patients with less than 40% BSA burn, 55 micrograms kg-1 for 40-60% BSA burn, and 65 micrograms kg-1 for patients with greater than 60% BSA burn. These values were significantly higher than the value for control patients, which was 18 micrograms kg-1. 4. Burn injury induces a resistance to the neuromuscular effects of vecuronium, the magnitude of which is related to burn size.
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Affiliation(s)
- A K Mills
- Department of Anaesthesiology, Harvard Medical School, Boston, MA
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Abstract
The neuromuscular effects of atracurium were studied in acutely burned children, and in children at least 3 years after burn injury (controls). Thirty-one children were studied a total of 48 times. During nitrous oxide-narcotic anaesthesia, a single dose of atracurium was administered in each study and the twitch suppression recorded. Dose-response curves were established using least-squares regression techniques. The ED95 of atracurium in children recovered from burn injury was 0.27 mg kg-1, which is similar to that of normal children reported previously. During the first week of burn injury, the ED95 was 0.3 mg kg-1 irrespective of burn size, and was not significantly different from controls. After the first week of injury, in children with 20-60% body surface burn, the ED95 was twice normal, while in those with greater than 60% body surface burn, it probably may be increased up to 3.0 mg kg-1.
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Affiliation(s)
- A K Mills
- Department of Anaesthesiology, Harvard Medical School, Boston, Massachusetts
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Abstract
Changes in soluble protein and in peroxidase, esterase, and amylase enzymes during development of the pea plant (P. sativum) have been investigated using a horizontal method of acrylamide gel electrophoresis. Both qualitative and quantitative variation between organs at different stages of physiological development are recorded.
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Mills AK, Grigor J. 341. The mechanism of the deamination of amino-alcohols. Part II. Amino-alcohols derived from α-aminopropiophenone hydrochloride. ACTA ACUST UNITED AC 1934. [DOI: 10.1039/jr9340001568] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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