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Miller RM, Heishman AD, Freitas ED, Bemben MG. Barbell velocity: a practical and precise method for predicting bench press strength in sedentary women. J Sports Med Phys Fitness 2019; 60:338-344. [PMID: 31684703 DOI: 10.23736/s0022-4707.19.10130-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Bench press one-repetition maximum (BP1RM) prediction models offer a timely approach to predict BP1RM while avoiding the limitations with traditional BP1RM testing. Interestingly, no models have determined the ability for a traditional weight, the 20.5 kg barbell, to predict BP1RM strength. Few models have exclusively examined females and sedentary individuals, leaving the accuracy of these models unknown for these populations. Therefore, this investigation sought to examine the ability for 20.5 kg barbell velocity to predict BP1RM in sedentary females. METHODS Nineteen sedentary females (21.79±1.43 years, 166.08±7.76 cm, 63.98±7.54 kg, 31.57±4.72 BP1RM) completed BP1RM testing and completed two additional visits to determine 20.5 kg barbell velocity from a single repetition separated by 7-10 days. Nineteen additional females (21.39±1.09 years, 164.31±7.37 cm, 67.34±9.32 kg, 32.75±5.09 BP1RM) served as a cross-validating group completing identical testing procedures. RESULTS Regression analyses revealed that 20.5 kg barbell velocity accounted for 95% of the variance in BP1RM strength while presenting marginal standard error (1.34 kg) and mean absolute error (0.97 kg), with similar values observed in the cross-validating group (SEE: 2.13 kg, MAE: 1.56 kg). Predicted BP1RM values were not significantly different from actual BP1RM (P=0.43) nor were measures in barbell velocity between trials 1 and 2 (P=0.57), while displaying high reliability (ICC: 0.81). Measure bias between BP1RM methods was 0.449±1.651kg and the agreement between methods varied between -2.78 kg less and 0.3686 kg greater for 95% of the participants. CONCLUSIONS The present data provides an accurate prediction model regarding BP1RM for sedentary females. These findings can reduce the limitations associated with traditional BP1RM testing while providing a practical and accurate BP1RM approximation with marginal error.
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Freitas EDS, Miller RM, Heishman AD, Aniceto RR, Silva JGC, Bemben MG. Perceptual responses to continuous versus intermittent blood flow restriction exercise: A randomized controlled trial. Physiol Behav 2019; 212:112717. [PMID: 31629764 DOI: 10.1016/j.physbeh.2019.112717] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 10/16/2019] [Accepted: 10/16/2019] [Indexed: 11/29/2022]
Abstract
We investigated the perceptual responses to resistance exercise (RE) with continuous and intermittent blood flow restriction (BFR). Fourteen males randomly completed the following exercise conditions: low-load RE with continuous BFR (cBFR), low-load RE with intermittent BFR (iBFR), low-load RE without BFR (LI), and traditional high-load RE (HI). Participants completed 4 sets of 30-15-15-15 repetitions of bilateral leg press and knee extension exercises during the low-load conditions, at 20% of one-repetition maximum (1-RM), a 1.5‑sec metronome-controlled pace, with a 1-min rest interval between sets; HI consisted of 4 sets of 10 repetitions of the same exercises, at 70% 1-RM, with the same pace and rest interval. Ratings of perceived exertion (RPE) and discomfort were assessed using psychometric scales before exercise and after each set. RPE displayed no significant differences (p > 0.05) between the BFR conditions for either exercise. Additionally, both BFR conditions elicited significantly (p < 0.05) greater RPE than LI and significantly (p <0.05) lower RPE than HI during both exercises. Rating of discomfort displayed no significant differences between BFR conditions during the first two sets of leg press; however, cBFR evoked greater discomfort compared to iBFR during the last two sets. There were no significant (p > 0.05) differences observed between conditions during the knee extension exercise. Rating of discomfort was similar between the BFR and HI conditions and each were significantly greater than LI during both exercises. Therefore, cBFR and iBFR seem to produce similar perceptual responses, which are greater than LI and lower than HI, but similar in regards to discomfort.
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Freitas EDS, Miller RM, Heishman AD, Kaur J, Brown BS, Silva JCG, Aniceto RR, Ferreira-Junior JB, Bemben MG. The Perceptual Responses to Continuous vs Intermittent Blood Flow Restriction Resistance Exercise. Med Sci Sports Exerc 2019. [DOI: 10.1249/01.mss.0000561680.76495.d4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Kaur J, Miller RM, Freitas ED, Heishman A, Bemben DA, Bemben MG. Racial/Ethnic Differences in Bone Health, Bone Free Lean Mass, and Fat Mass in Young Women. Med Sci Sports Exerc 2019. [DOI: 10.1249/01.mss.0000562546.14686.45] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Heishman A, Miller RM, Freitas ED, Brown BS, Daub BD, Bemben MG. Monitoring External Training Loads and Neuromuscular Performance For Division I Basketball Players Over the Pre-Season. Med Sci Sports Exerc 2019. [DOI: 10.1249/01.mss.0000560595.64671.b6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Miller RM, Freitas ED, Heishman AD, Kaur J, Brown BS, Bemben MG. Obesity Further Impairs Neuromuscular and Functional Performance in Older Women. Med Sci Sports Exerc 2019. [DOI: 10.1249/01.mss.0000561755.22246.a0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Miller RM, Freitas ED, Heishman AD, Kaur J, Koziol KJ, Galletti BA, Bemben MG. Maximal power production as a function of sex and training status. Biol Sport 2019; 36:31-37. [PMID: 30899137 PMCID: PMC6413571 DOI: 10.5114/biolsport.2018.78904] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/30/2018] [Accepted: 06/26/2018] [Indexed: 11/17/2022] Open
Abstract
Maximal muscular power is achieved at lower percentages of maximal strength (1RM); however, this notion has not been elucidated based on sex or training status. Therefore, the purpose of this investigation was to examine the influence of sex and training status on maximal power production. Sixty men and women (resistance trained or untrained) completed 1RM testing for the two-leg press (2LP) and bench press (BP). Participants then returned to perform single repetitions at 20, 30, 40, 50, 60, 70 and 80% of their 1RM to determine muscular power. Factorial analyses determined significant interactions (training status by sex by intensity) for the BP (F=35.6, p<0.001) and 2LP (F=8.2, p<0.001). Subsequent analyses indicated that during the BP trained men produce maximal power between 30-40% 1RM compared to untrained men at 60-70% 1RM. Trained women produced maximal power at 50% 1RM compared to untrained women at 60-70% 1RM. During the 2LP, trained men produced maximal power at 40% 1RM compared to untrained men at 60% 1RM. Trained women produced maximal power at 50% 1RM compared to 60-70% 1RM in untrained women. These data suggest that resistance trained individuals and men display maximal power at a lower relative intensity than untrained individuals and women.
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Miller RM, Freitas EDS, Heishman AD, Stone BL, Bemben MG. The High Precision of Functional and Neuromuscular Measures to Classify Sarcopenia in Older Women. J Geriatr Phys Ther 2019; 42:E55-E61. [PMID: 30601293 DOI: 10.1519/jpt.0000000000000219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND AND PURPOSE Previous literature suggests that reductions in appendicular skeletal mass (ASM) may have a greater detrimental effect than total lean body mass regarding the onset and progression of sarcopenia. Unfortunately, limited access to equipment that accurately determines ASM often leads to many individuals remaining undiagnosed and experiencing functional decline. Therefore, the purpose of this investigation was to determine the ability of functional and neuromuscular measures to identify ASM in older women. METHODS Forty-one (sarcopenic n = 15) older women underwent body composition analysis via dual-energy X-ray absorptiometry (DXA) and performed the following measures: bench press (BP) 1-repetition maximum strength (1RM), vertical jump height and power, handgrip strength, Timed Up and Go test, Berg Balance Scale testing, and bench press power testing at 20%, 40%, and 60% 1RM. RESULTS AND DISCUSSION Regression analyses revealed 3 significant models accounting for 93.8%, 91.1%, and 86.4% of the variance in DXA-derived ASM. Paired-samples t tests revealed no significant differences between model-derived and DXA-derived ASM for each model, and each model was significantly correlated to DXA-derived ASM (P < .001). In addition, each model revealed a strong ability to appropriately classify sarcopenia status, with the area under the curve values ranging from 0.86 to 0.93. The present data indicate that ASM can be determined with high precision by measuring outcome variables such as jump power, body weight, and grip strength in older women. CONCLUSIONS Therefore, the present models could be used to identify, screen, or classify older women as sarcopenic, ultimately allowing the implementation of interventions aimed at decreasing the difficulty of activities of daily living and increasing quality of life.
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Miller RM, Keeter VM, Freitas EDS, Heishman AD, Knehans AW, Bemben DA, Bemben MG. Effects of Blood-Flow Restriction Combined With Postactivation Potentiation Stimuli on Jump Performance in Recreationally Active Men. J Strength Cond Res 2018; 32:1869-1874. [PMID: 28682937 DOI: 10.1519/jsc.0000000000002110] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Miller, RM, Keeter, VM, Freitas, EDS, Heishman, AD, Knehans, AW, Bemben, DA, and Bemben, MG. Effects of blood-flow restriction combined with postactivation potentiation stimuli on jump performance in recreationally active men. J Strength Cond Res 32(7): 1869-1874, 2018-Whole-body vibration (WBV) and maximum voluntary contractions (MVCs) combined with blood-flow restriction (BFR) to augment postactivation potentiation have yet to be examined. Therefore, the purpose of this investigation was to examine the augmented effects of postactivation potentiation when WBV and MVC are combined with BFR. Twenty men (21.8 ± 2.6 years, 180.5 ± 6.2 cm and 84.5 ± 12.1 kg) completed the study. Participants completed 3 testing sessions in a randomized design that included one of the following: (a) control (CON), (b) WBV and WBV combined with BFR (WBV + BFR), or (c) MVC and MVC combined with BFR (MVC + BFR). Jump height and power were recorded for 3 trials, PRE and POST jump height (cm) mean ± SD for each were as follows: CON 58.9 ± 8.6 and 57.9 ± 8.6, WBV 58.2 ± 8.1 and 59.9 ± 8.1, WBV + BFR 58.7 ± 7.6 and 60.2 ± 8.1, MVC 59.7 ± 7.4 and 60.2 ± 8.6, and MVC + BFR 57.7 ± 7.9 and 59.4 ± 8.1. PRE and POST jump power (W) mean ± SD for each were as follows: CON 1,224.3 ± 221.5 and 1,234.3 ± 189.2, WBV 1,251.1 ± 230.4 and 1,266.1 ± 215.7, WBV + BFR 1,265.8 ± 207.9 and 1,259 ± 223.3, MVC 1,264.7 ± 211.9 and 1,263.5 ± 236.5, and MVC + BFR 1,252.3 ± 222.0 and 1,294.6 ± 256.6. Significant differences were revealed in jump height between the 5 interventions (p < 0.01), WBV (p < 0.01), WBV + BFR (p < 0.01), and MVC + BFR (p < 0.01) revealed significant differences in time but no differences in jump power. In conclusion, the results of this study indicate that WBV, WBV + BFR, and MVC + BFR significantly improve jump height and time in air but not jump power.
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Freitas EDS, Frederiksen C, Miller RM, Heishman A, Anderson M, Pardo G, Fjeldstad C, Bemben DA, Bemben MG. Acute and Chronic Effects of Whole-Body Vibration on Balance, Postural Stability, and Mobility in Women With Multiple Sclerosis. Dose Response 2018; 16:1559325818816577. [PMID: 30627068 PMCID: PMC6311586 DOI: 10.1177/1559325818816577] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 10/02/2018] [Accepted: 10/25/2018] [Indexed: 01/16/2023] Open
Abstract
The acute and chronic effects of whole-body vibration (WBV) on balance, postural stability, and mobility were evaluated in 21 women with relapsing-remitting multiple sclerosis (MS) randomly assigned to control (n = 9) or experimental (n = 12) groups. To assess acute responses, outcome variables were assessed before and immediately after a session of WBV (five 30-second bouts of vibration; frequency 30 Hz; amplitude 3 mm; 1-minute rest intervals) during their first visit (week 1) using field (Timed-Up and Go; 500-m walk; Berg Balance Scale) and laboratory tests (NeuroCom Balance Master and EquiTest System-Sensory Organization Test, Adaptation Test, Limits of Stability, Modified Clinical Test for Sensory Integration of Balance, Unilateral Stance, Tandem Walk, Step/Quick Turn). Acute responses were also measured after their fifth visit for only the Adaptation and Sensory Organization tests. For the chronic responses, participants were exposed to the WBV protocol once a week, for a total of 5 weeks, and then at week 5, were reassessed with the Adaptation and the Sensory Organization tests. Neither acute nor chronic exposure to the WBV protocols used in this study resulted in significant improvements (P > .05) in balance, postural stability, or mobility as assessed by either field or laboratory tests. However, based on promising results from other studies that have used WBV with other clinical populations, either alone or in conjunction with exercise, additional studies that increase the dose of vibration exposure, both acutely and chronically, should be conducted in patients with MS.
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Miller RM, Heishman AD, Freitas EDS, Bemben MG. Comparing the Acute Effects of Intermittent and Continuous Whole-Body Vibration Exposure on Neuromuscular and Functional Measures in Sarcopenia and Nonsarcopenic Elderly Women. Dose Response 2018; 16:1559325818797009. [PMID: 30202250 PMCID: PMC6125857 DOI: 10.1177/1559325818797009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 07/26/2018] [Accepted: 07/31/2018] [Indexed: 11/16/2022] Open
Abstract
This investigation examined the acute effects of continuous whole-body vibration (CWBV) and intermittent whole-body vibration (IWBV) on neuromuscular and functional measures in women with sarcopenia and nonsarcopenic women. Continuous whole-body vibration was one 6-minute exposure, while IWBV consisted of six 60-second exposures to rest intervals (30 Hz, 2-4 mm amplitude). Factorial analyses revealed group × exposure × time interactions for jump height (JH; F = 10.8, P = .002), grip strength (GS; F = 15.5, P < .001), timed up and go test (F = 11.7, P = .002), and sit and reach test (S&R; F = 9.7, P = .004). Both JH and GS significantly improved post-WBV in women with sarcopenia (P < .001), with post-IWBV significantly greater (P < .001) than post-CWBV. Timed up and go test and S&R significantly improved post-IWBV in both the groups (P < .001) with post-IWBV significantly better than post-CWBV (P < .001). Bench press power at 20% one repetition maximum (1RM) revealed an exposure × time interaction (F = 4.6, P = .04) illuminating that IWBV significantly improved muscular power (P < .001). Bench press power at 40% 1RM revealed group × exposure (F = 6.4, P = .016) and exposure × time interactions (F = 5.8, P = .022). Individuals with sarcopenia significantly increased power output (P < .001) post-IWBV which was significantly greater than post-CWBV (P = .037). Bench press power at 60% 1RM revealed an exposure × time interaction (F = 8.6, P = .006), indicating that power was significantly improved post-IWBV (P = .027) and decreased post-CWBV. Berg Balance scale revealed a time main effect (F = 6.64, P = .015), and pain discomfort was significantly lower post-IWBV. These data indicate IWBV may provide a more efficacious exposure pattern in older women when compared to CWBV.
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Heishman AD, Miller RM, Freitas ED, Kaur J, Galletti BA, Koziol KJ, Bemben MG. Countermovement Jump Reliability when Performed With and Without an Arm Swing in NCAA Division 1 Basketball Players. Med Sci Sports Exerc 2018. [DOI: 10.1249/01.mss.0000538208.39002.8d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Miller RM, Freitas ED, Heishman AD, Kaur J, Koziol KJ, Galletti BA, Bemben MG. The Effects of Gender and Training Status on Optimal Loads for Developing Muscular Power. Med Sci Sports Exerc 2018. [DOI: 10.1249/01.mss.0000538600.56367.56] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Koziol KJ, Miller RM, Freitas EDS, Heishman AD, Kaur J, Bemben MG. Test-retest Reliability of Velocity Assessments for Free Weight and Machine Exercises. Med Sci Sports Exerc 2018. [DOI: 10.1249/01.mss.0000538206.31379.7b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Freitas E, Frederiksen C, Miller RM, Heishman AD, Kaur J, Koziol KJ, Galletti BAR, Bemben DA, Bemben MG. The Effects Of Whole-body Vibration On Posture, Balance, And Mobility In Women With Multiple Sclerosis. Med Sci Sports Exerc 2018. [DOI: 10.1249/01.mss.0000535115.77076.a1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Stone B, Miller RM, Heishman AD, Campbell JA, Kellawan JM. Fitness and Performance Responses to Load Carriage Specific Training in Reserved Officers Training Corps. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.855.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Miller RM, Strohmeyer HS, Bemben MG. Comparisons Between Jump Power, Swing Velocity, and Hitting Measures in Collegiate Baseball and Softball Athletes. Med Sci Sports Exerc 2017. [DOI: 10.1249/01.mss.0000518635.32749.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Miller RM, Chambers TL, Burns SP, Godard MP. Validating InBody® 570 Multi-frequency Bioelectrical Impedance Analyzer versus DXA for Body Fat Percentage Analysis. Med Sci Sports Exerc 2016. [DOI: 10.1249/01.mss.0000487979.68551.d7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Miller RM, Rohde KA, Tingle MTA, Moran JJM, Hayney MS. Antibody responses to influenza vaccine in pre- and post-lung transplant patients. Clin Transplant 2016; 30:606-12. [PMID: 26928266 DOI: 10.1111/ctr.12726] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/24/2016] [Indexed: 11/29/2022]
Abstract
BACKGROUND Although pre-transplant immunization is routinely recommended, this recommendation is based on little data. The primary objective of this study was to compare antibody responses in lung transplant patients who received influenza vaccine before the transplant, within the first six months of transplant, between 13 and 60 months post-transplant, and 110 months or beyond transplant. METHODS This prospective cohort study included 357 total immunization events performed over five yr to measure H1N1, H3N2, and B antibody responses to the influenza vaccine in pre- and post-lung transplant patients. Geometric mean titers, seroprotection (antibody titer at least 1:40), seroconversion (fourfold increase between pre and post), and mean fold increases were compared. RESULTS The geometric mean titer distributions were different for H3N2 and B (ANOVA; p = 0.002 for both). Pre-transplant antibody concentrations were higher compared to the 13- to 60-month group for H3N2 (corrected p = 0.002) and the healthy group for B (corrected p = 0.001). The ≥110-month group had higher seroconversion rates compared to the 13- to 60-month group for H3N2 and B viruses. CONCLUSION Lung pre-transplant patients and the long-term survivors have higher responses to the influenza vaccine than early post-transplant and the transplant control groups.
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Miller RM, Zhang X, Maxwell A, Cain C, Xu Z. Bubble-Induced Color Doppler Feedback for Histotripsy Tissue Fractionation. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2016; 63:408-19. [PMID: 26863659 PMCID: PMC4838481 DOI: 10.1109/tuffc.2016.2525859] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Histotripsy therapy produces cavitating bubble clouds to increasingly fractionate and eventually liquefy tissue using high-intensity ultrasound pulses. Following cavitation generated by each pulse, coherent motion of the cavitation residual nuclei can be detected using metrics formed from ultrasound color Doppler acquisitions. In this paper, three experiments were performed to investigate the characteristics of this motion as real-time feedback on histotripsy tissue fractionation. In the first experiment, bubble-induced color Doppler (BCD) and particle image velocimetry (PIV) analysis monitored the residual cavitation nuclei in the treatment region in an agarose tissue phantom treated with two-cycle histotripsy pulses at [Formula: see text] using a 500-kHz transducer. Both BCD and PIV results showed brief chaotic motion of the residual nuclei followed by coherent motion first moving away from the transducer and then rebounding back. Velocity measurements from both PIV and BCD agreed well, showing a monotonic increase in rebound time up to a saturation point for increased therapy dose. In a second experiment, a thin layer of red blood cells (RBC) was added to the phantom to allow quantification of the fractionation of the RBC layer to compare with BCD metrics. A strong linear correlation was observed between the fractionation level and the time to BCD peak rebound velocity over histotripsy treatment. Finally, the correlation between BCD feedback and histotripsy tissue fractionation was validated in ex vivo porcine liver evaluated histologically. BCD metrics showed strong linear correlation with fractionation progression, suggesting that BCD provides useful quantitative real-time feedback on histotripsy treatment progression.
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Zhang X, Miller RM, Lin KW, Levin AM, Owens GE, Gurm HS, Cain CA, Xu Z. Real-time feedback of histotripsy thrombolysis using bubble-induced color Doppler. ULTRASOUND IN MEDICINE & BIOLOGY 2015; 41:1386-401. [PMID: 25623821 PMCID: PMC4398659 DOI: 10.1016/j.ultrasmedbio.2014.12.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 11/25/2014] [Accepted: 12/10/2014] [Indexed: 05/06/2023]
Abstract
Histotripsy thrombolysis is a non-invasive, drug-free, image-guided therapy that fractionates blood clots using well-controlled acoustic cavitation alone. Real-time quantitative feedback is highly desired during histotripsy thrombolysis treatment to monitor the progress of clot fractionation. Bubble-induced color Doppler (BCD) monitors the motion after cavitation generated by each histotripsy pulse, which has been found in gel and ex vivo liver tissue to be correlated with histotripsy fractionation. We investigated the potential of BCD to quantitatively monitor histotripsy thrombolysis in real time. To visualize clot fractionation, transparent three-layered fibrin clots were developed. Results indicated that a coherent motion follows the cavitation generated by each histotripsy pulse with a push and rebound pattern. The temporal profile of this motion expands and saturates as treatment progresses. A strong correlation exists between the degree of histotripsy clot fractionation and two metrics extracted from BCD: time of peak rebound velocity (tPRV) and focal mean velocity at a fixed delay (Vf,delay). The saturation of clot fractionation (i.e., treatment completion) matches well the saturations detected using tPRV and Vf,delay. The mean Pearson correlation coefficients between the progression of clot fractionation and the two BCD metrics were 93.1% and 92.6%, respectively. To validate BCD feedback in in vitro clots, debris volumes from histotripsy thrombolysis were obtained at different therapy doses and compared with Vf,delay. There is also good agreement between the increasing and saturation trends of debris volume and Vf,delay. Finally, a real-time BCD feedback algorithm to predict complete clot fractionation during histotripsy thrombolysis was developed and tested. This work illustrates the potential of BCD to monitor histotripsy thrombolysis treatment in real time.
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Miller RM, Hayney MS. Immunization information systems: A decade of progress. J Am Pharm Assoc (2003) 2015; 55:104-5. [DOI: 10.1331/japha.2014.15503] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Miller RM, Hannikainen IA, Cushman FA. Bad actions or bad outcomes? Differentiating affective contributions to the moral condemnation of harm. ACTA ACUST UNITED AC 2014; 14:573-87. [PMID: 24512250 DOI: 10.1037/a0035361] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Moral condemnation of harmful behavior is influenced by both cognitive and affective processes. However, despite much recent research, the proximate source of affect remains unclear. One obvious contender is empathy; simulating the victim's pain could lead one to judge an action as wrong ("outcome aversion"). An alternative, less obvious source is one's own aversion to performing the action itself ("action aversion"). To dissociate these alternatives, we developed a scale that assessed individual aversions to (a) witnessing others experience painful outcomes (e.g., seeing someone fall down stairs); and (b) performing actions that are harmless yet aversive (e.g., stabbing a fellow actor with a fake stage knife). Across 4 experiments, we found that moral condemnation of both first-person and third-party harmful behavior in the context of moral dilemmas is better predicted by one's aversion to action properties than by an affective response to victim suffering. In a fifth experiment, we manipulated both action aversion and the degree of expected suffering across a number of actions and found that both factors make large, independent contributions to moral judgment. Together, these results suggest we may judge others' actions by imagining what it would feel like to perform the action rather than experience the consequences of the action. Accordingly, they provide a counterpoint to a dominant but largely untested assumption that empathy is the key affective response governing moral judgments of harm.
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Miller RM, Price JR, Batty EM, Didelot X, Wyllie D, Golubchik T, Crook DW, Paul J, Peto TEA, Wilson DJ, Cule M, Ip CLC, Day NPJ, Moore CE, Bowden R, Llewelyn MJ. Healthcare-associated outbreak of meticillin-resistant Staphylococcus aureus bacteraemia: role of a cryptic variant of an epidemic clone. J Hosp Infect 2013; 86:83-9. [PMID: 24433924 PMCID: PMC3924019 DOI: 10.1016/j.jhin.2013.11.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 11/20/2013] [Indexed: 12/21/2022]
Abstract
Background New strains of meticillin-resistant Staphylococcus aureus (MRSA) may be associated with changes in rates of disease or clinical presentation. Conventional typing techniques may not detect new clonal variants that underlie changes in epidemiology or clinical phenotype. Aim To investigate the role of clonal variants of MRSA in an outbreak of MRSA bacteraemia at a hospital in England. Methods Bacteraemia isolates of the major UK lineages (EMRSA-15 and -16) from before and after the outbreak were analysed by whole-genome sequencing in the context of epidemiological and clinical data. For comparison, EMRSA-15 and -16 isolates from another hospital in England were sequenced. A clonal variant of EMRSA-16 was identified at the outbreak hospital and a molecular signature test designed to distinguish variant isolates among further EMRSA-16 strains. Findings By whole-genome sequencing, EMRSA-16 isolates during the outbreak showed strikingly low genetic diversity (P < 1 × 10−6, Monte Carlo test), compared with EMRSA-15 and EMRSA-16 isolates from before the outbreak or the comparator hospital, demonstrating the emergence of a clonal variant. The variant was indistinguishable from the ancestral strain by conventional typing. This clonal variant accounted for 64/72 (89%) of EMRSA-16 bacteraemia isolates at the outbreak hospital from 2006. Conclusions Evolutionary changes in epidemic MRSA strains not detected by conventional typing may be associated with changes in disease epidemiology. Rapid and affordable technologies for whole-genome sequencing are becoming available with the potential to identify and track the emergence of variants of highly clonal organisms.
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Miller RM, Kim Y, Lin KW, Cain CA, Owens GE, Xu Z. Histotripsy cardiac therapy system integrated with real-time motion correction. ULTRASOUND IN MEDICINE & BIOLOGY 2013; 39:2362-73. [PMID: 24063958 PMCID: PMC3881374 DOI: 10.1016/j.ultrasmedbio.2013.08.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Revised: 06/28/2013] [Accepted: 08/01/2013] [Indexed: 05/25/2023]
Abstract
Histotripsy has shown promise in non-invasive cardiac therapy for neonatal and fetal applications. However, for cardiac applications in general, and especially in the adult heart, cardiac and respiratory motion may affect treatment accuracy and efficacy. In this article, we describe a histotripsy-mediated cardiac therapy system integrated with a fast motion tracking algorithm and treatment monitoring using ultrasound imaging. Motion tracking is performed by diamond search block matching in real-time ultrasound images using a reference image of the moving target, refined by Kalman filtering. As proof of feasibility, this algorithm was configured to track 2-D target motion and then electronically adjust the focus of a 1-MHz annular therapy array to correct for axial motion. This integrated motion tracking system is capable of sub-millimeter accuracy for displacements of 0-15 mm and velocities of 0-80 mm/s, with a maximum error less than 3 mm. Tissue phantom tests indicated that treatment efficiency and lesion size using motion tracking over displacements of 0-15 mm and velocities of 0-42 mm/s are comparable to those achieved when treating stationary targets. In vivo validation was conducted in an open-chest canine model, where the system provided 24 min of motion-corrected histotripsy therapy in the live beating heart, generating a targeted lesion on the atrial septum. Based on this proof of feasibility and the natural extension of these techniques to three dimensions, we anticipate a full motion correction system would be feasible and beneficial for non-invasive cardiac therapy.
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