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Totzkay D, Silk KJ, Thomas B, Walling BM, Smith SW. Women's Understanding of Windows of Susceptibility and the Role of the Environment in Breast Cancer Risk. J Cancer Educ 2023; 38:115-126. [PMID: 34505275 PMCID: PMC8907316 DOI: 10.1007/s13187-021-02086-z] [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] [Subscribe] [Scholar Register] [Accepted: 09/02/2021] [Indexed: 06/13/2023]
Abstract
Emerging evidence suggests women who are exposed to harmful environmental exposures, especially during certain critical periods across the lifespan, may increase their breast cancer risk. Such windows of susceptibility (WoS) occur throughout a woman's lifetime, during which she is especially vulnerable to the effects of harmful environmental exposures. This interaction makes the reduction of harmful environmental toxicants during those time periods a priority for community health promotion. Communicating about environmental exposures and their impact on women's health requires an assessment of sense-making around, and understanding of, the link between breast cancer and the environment. To that end, focus groups were conducted to assess the themes that emerge when women make sense of (a) their own breast cancer risk, (b) the environment-cancer connection, and (c) WoS. Results provide insight into how women understand these issues which can inform messaging strategies focused on reducing harmful environmental exposures. Implications are discussed within the context of communication efforts tailored to educate women, particularly mothers with daughters in the prepubertal and pubertal WoS who are particularly vulnerable to harmful environmental exposures.
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Affiliation(s)
- D Totzkay
- West Virginia University, Morgantown, WV, USA
| | - K J Silk
- University of Delaware, Newark, DE, USA
| | - B Thomas
- Michigan State University, East Lansing, MI, USA
| | - B M Walling
- Michigan State University, East Lansing, MI, USA
| | - S W Smith
- Michigan State University, East Lansing, MI, USA.
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Sandoval Y, Smith SW, Schulz K, Sexter A, Apple FS. P3608Long-term mortality and mode of death among patients with type 1 and 2 myocardial infarction. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz745.0467] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Few studies address long-term outcomes among patients with type 2 myocardial infarction (T2MI). It has been suggested that patients with T2MI with concomitant stable ischemic heart disease are at higher-risk.
Purpose
Our goals were two-fold. First, to examine 5-year mortality rates and mode of death among patients with type 1 (T1MI) and T2MI. Second, to evaluate the prognostic impact of coronary artery disease (CAD) on long-term outcomes among patients with T2MI.
Methods
Post-hoc analysis of UTROPIA (NCT02060760), a prospective, observational cohort study involving 1,640 consecutive emergency department patients with serial cardiac troponin (cTn) I measurements obtained on clinical indication. 5-year death rates, including mode of death, were examined among patients with T1MI and T2MI. CAD was defined as the presence of any of the following: history of CAD, prior MI, prior coronary artery bypass graft surgery, prior percutaneous coronary intervention, prior coronary stenting, or documented CAD (≥50%) on index admission angiography.
Results
Among 1640 patients, acute MI was diagnosed in 217 patients, including 77 (4.7%) classified as T1MI and 140 (8.5%) as T2MI. At 5-years, 23% (n=18) of patients with T1MI had died, with 61% (n=11) categorized as cardiac deaths. For T2MI, 37% (n=52) had died at 5-years, with 36% (n=19) categorized as cardiac deaths. Patients with T2MI had a higher 5-year mortality than T1MI (37% vs 23%, p=0.038) (Figure, Panel A), with T2MI more likely than T1MI to die from non-cardiac causes (64% vs. 39%, p=0.04). CAD was present in 22% (n=31) of patients with T2MI and associated with worse outcomes (p=0.0496) (Figure, Panel B).
Conclusion
T2MI has worse long term outcomes than T1MI. The predominant mode of death among patients with T2MI is non-cardiac. However, approximately 40% of deaths are cardiac. Further, we confirm the presence of CAD identifies a subset of patients with T2MI at high-risk.
Acknowledgement/Funding
Abbott Diagnostics and Hennepin Healthcare Research Institute (formerly MMRF)
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Affiliation(s)
- Y Sandoval
- Mayo Clinic, Rochester, United States of America
| | - S W Smith
- Hennepin County Medical Center, Minneapolis, United States of America
| | - K Schulz
- Hennepin Healthcare Research Institute, Minneapolis, United States of America
| | - A Sexter
- Hennepin Healthcare Research Institute, Minneapolis, United States of America
| | - F S Apple
- Hennepin County Medical Center, Minneapolis, United States of America
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Sandoval Y, Smith SW, Schulz K, Sexter A, Apple FS. P851Incidence and prognostic impact of acute infection among patients with type 1 and 2 myocardial infarction. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz747.0449] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
The incidence and impact of acute infection among patients with type 1 (T1MI) and 2 myocardial infarction (T2MI) is not well known. Inflammation and increased procoagulant activity can lead to T1MI, whereas cytokine release can cause hemodynamic alterations affecting myocardial oxygen consumption and contribute to T2MI.
Purpose
Determine the incidence and prognostic impact of acute infection among patients with T1MI and T2MI.
Methods
Post-hoc analysis of UTROPIA (NCT02060760), a prospective, observational cohort study involving 1,640 consecutive emergency department patients with serial cardiac troponin (cTn) I measurements obtained on clinical indication. The incidence of acute infection, antibiotic use, and/or laboratory evidence of infection were examined among patients with T1MI and T2MI. 5-year cumulative survival curves were plotted using the Kaplan-Meier method, frequencies were compared via Chi-Square, and a multivariate cox-proportional hazards model was used to assess the impact of infection on mortality.
Results
Among 217 patients with acute MI (T1MI, n=77 and T2MI, n=140), acute infection occurred in 63 (29%) of patients. Acute infection was more common in patients with T2MI than T1MI (35% vs. 18%, p=0.009). The predominant source of infection was pneumonia (59%), followed by urinary tract infections (11%). Patients with T2MI were also more likely than T1MI to have sepsis (11% vs. 1%, p=0.012), bacteremia (30% vs. 18%, p=0.057), and antibiotic use (35% vs. 17%, p=0.005). At 5-years, patients with acute MI and acute infection had a higher mortality rate than patients without infection (49% vs. 25%, p=0.0006) (Figure). Among the 31 deaths in MI patients with acute infection, most deaths were non-cardiac (65%) and occurred in those with T2MI (77%). Following adjustment for age, sex, and comorbidities in a Cox proportional hazards model, acute infection was an independent predictor of death (hazard ratio: 2.2, 95% CI: 1.3–3.5, p=0.0016).
Conclusion
Acute infection occurs in almost a third of patients that are diagnosed with acute MI during the index hospitalization. Most infections are due to pneumonia and occur most often in patients classified as having T2MI. Acute infection is an independent risk factor for 5-year mortality, with nearly half of all patients with acute MI in whom concomitant acute infection is present during the index hospitalization dead at 5-years. Most deaths are non-cardiac and the vast majority occur in patients with T2MI.
Acknowledgement/Funding
Abbott Diagnostics and Hennepin Healthcare Research Institute (formerly MMRF)e
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Affiliation(s)
- Y Sandoval
- Mayo Clinic, Rochester, United States of America
| | - S W Smith
- Hennepin County Medical Center, Minneapolis, United States of America
| | - K Schulz
- Hennepin Healthcare Research Institute, Minneapolis, United States of America
| | - A Sexter
- Hennepin Healthcare Research Institute, Minneapolis, United States of America
| | - F S Apple
- Hennepin County Medical Center, Minneapolis, United States of America
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Berenger BM, Doucette K, Smith SW. Epidemiology and risk factors for nosocomial bloodstream infections in solid organ transplants over a 10-year period. Transpl Infect Dis 2016; 18:183-90. [PMID: 26818427 DOI: 10.1111/tid.12505] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 10/09/2015] [Accepted: 12/03/2015] [Indexed: 11/28/2022]
Abstract
BACKGROUND Bloodstream infections (BSIs) are a leading cause of morbidity and mortality in solid organ transplantation (SOT). We sought to determine the types of nosocomial BSIs and risk factors for them in SOT. METHODS Prospectively collected databases of all SOT and nosocomial BSIs occurring at our institution for a 10-year period were reviewed. RESULTS From 2003-2012, we observed 157 nosocomial BSI episodes in 2257 SOTs, the majority of which were caused by staphylococci and enterococci (67.5%). The most common sources of BSI were central line, organ space, respiratory, and gastrointestinal. Kidney transplant patients had the lowest risk of acquiring a BSI compared with other SOT types. Lung transplant patients were at increased risk of methicillin-resistant Staphylococcus aureus BSI and heart transplant patients were at increased risk of a Candida albicans BSI, when compared to other organ transplant types. When coagulase-negative Staphylococcus (CoNS) or C. albicans was isolated, the central line was most often the source. The implementation of central-line bundles during the study period correlated temporally with a decreased rate of CoNS BSI. Over the 10-year period, vancomycin-resistant enterococci became the most common enterococcal BSI. Donor-positive cytomegalovirus status was associated with an increased risk of BSI, when compared to donor-negative patients. CONCLUSIONS This study demonstrates the common sources, risk factors, and causative organisms of BSI, which can guide empiric antibiotic choices, and highlights areas where preventative interventions could be targeted to prevent nosocomial BSI in SOT.
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Affiliation(s)
- B M Berenger
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada.,Alberta Provincial Laboratory for Public Health, Edmonton, Alberta, Canada
| | - K Doucette
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - S W Smith
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
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Laskowski LK, Nelson LS, Smith SW, Hoffman RS. Authors' response to: "Beta-blocker treatment of caffeine-induced tachydysrhythmias". Clin Toxicol (Phila) 2016; 54:467. [PMID: 27005678 DOI: 10.3109/15563650.2016.1159313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- L K Laskowski
- a Ronald O. Perelman Department of Emergency Medicine , New York University School of Medicine , New York city , NY , USA ;,b New York City Poison Control Center , New York city , NY , USA
| | - L S Nelson
- a Ronald O. Perelman Department of Emergency Medicine , New York University School of Medicine , New York city , NY , USA ;,b New York City Poison Control Center , New York city , NY , USA
| | - S W Smith
- a Ronald O. Perelman Department of Emergency Medicine , New York University School of Medicine , New York city , NY , USA ;,b New York City Poison Control Center , New York city , NY , USA
| | - R S Hoffman
- a Ronald O. Perelman Department of Emergency Medicine , New York University School of Medicine , New York city , NY , USA ;,b New York City Poison Control Center , New York city , NY , USA
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Lampert LF, Barnum A, Smith SW, Conley JF, Jiao J. Phase transitions and in situ dynamics of crystal grain formation of alumina nanotubes templated by vertically aligned carbon nanotubes. RSC Adv 2015. [DOI: 10.1039/c5ra12337b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Vertically aligned alumina nanotubes created by atomic layer deposition onto carbon nanotubes scaffolds are synthesized and analyzed for phase transitionsviathermal annealing andin situelectron-irradiation induced crystallization.
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Affiliation(s)
- L. F. Lampert
- Department of Physics and Mechanical & Materials Engineering
- Portland State University
- Portland
- USA
| | - A. Barnum
- Department of Physics and Mechanical & Materials Engineering
- Portland State University
- Portland
- USA
| | - S. W. Smith
- School of Engineering & Computer Science
- 3089 Kelley Engineering Center
- Oregon State University
- Corvallis
- USA
| | - J. F. Conley
- School of Engineering & Computer Science
- 3089 Kelley Engineering Center
- Oregon State University
- Corvallis
- USA
| | - J. Jiao
- Department of Physics and Mechanical & Materials Engineering
- Portland State University
- Portland
- USA
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Chen BC, Shawn LK, Connors NJ, Wheeler K, Williams N, Hoffman RS, Matte TD, Smith SW. Carbon monoxide exposures in New York City following Hurricane Sandy in 2012. Clin Toxicol (Phila) 2013; 51:879-85. [DOI: 10.3109/15563650.2013.839030] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Taboulet P, Smith SW, Brady WJ. Diagnostic ECG du syndrome coronarien aigu. Partie 3. Les anomalies des complexes QRS. Ann Fr Med Urgence 2013. [DOI: 10.1007/s13341-013-0279-5] [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: 10/27/2022]
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Smith SW, Schrimpf C, Parekh DJ, Venkatachalam M, Duffield JS. Kidney pericytes: a novel therapeutic target in interstitial fibrosis. Histol Histopathol 2013; 27:1503-14. [PMID: 23059881 DOI: 10.14670/hh-27.1503] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Chronic Kidney Disease affects approximately 8% of the population and contributes considerably to premature morbidity and mortality. Recently reported studies have highlighted an important role for resident microvascular pericytes in the pathogenesis of kidney fibrosis. Pericytes are emerging as the predominant source of the activated, matrix depositing, stromal cell population seen in progressive fibrosis. Further, pericyte activation leads to their detachment from the vasculature, triggers unstable microvasculature and leads to rarefaction. Strategies to modulate pericyte function in these processes are therefore therapeutically attractive. In this review we will first describe our current understanding of the structure and function of the pericyte and the role these cells play in angiogenesis and the pathogenesis of renal fibrosis. Novel therapeutic approaches targeting pericytes in murine models of renal disease will then be considered.
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Affiliation(s)
- S W Smith
- Renal research group, Institute of Biomedical Research, University of Birmingham, UK
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Taboulet P, Smith SW, Brady WJ. Diagnostic ECG du syndrome coronarien aigu. Ann Fr Med Urgence 2013. [DOI: 10.1007/s13341-012-0272-z] [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: 10/27/2022]
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Hills CE, Siamantouras E, Smith SW, Cockwell P, Liu KK, Squires PE. TGFβ modulates cell-to-cell communication in early epithelial-to-mesenchymal transition. Diabetologia 2012; 55:812-24. [PMID: 22215279 DOI: 10.1007/s00125-011-2409-9] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Accepted: 11/10/2011] [Indexed: 10/14/2022]
Abstract
AIMS/HYPOTHESIS A key pathology in diabetic nephropathy is tubulointerstitial fibrosis. The condition is characterised by increased deposition of the extracellular matrix, fibrotic scar formation and declining renal function, with the prosclerotic cytokine TGF-β1 mediating many of these catastrophic changes. Here we investigated whether TGF-β1-induced epithelial-to-mesenchymal transition (EMT) plays a role in alterations in cell adhesion, cell coupling and cell communication in the human renal proximal tubule. METHODS Whole-cell and cell compartment abundance of E-cadherin, N-cadherin, snail, vimentin, β-catenin and connexin-43 was determined in human kidney cell line (HK)2 and human proximal tubule cells with or without TGF-β1, using western blotting and immunocytochemistry, followed by quantification by densitometry. The contribution of connexin-43 in proximal tubule cell communication was quantified using small interfering RNA knockdown, while dye-transfer was used to assess gap junctional intercellular communication (GJIC). Functional tethering was assessed by single-cell force spectroscopy with or without TGF-β1, or by immunoneutralisation of cadherin ligation. RESULTS High glucose (25 mmol/l) increased the secretion of TGF-β1 from HK2 cells. Analysis confirmed early TGF-β1-induced morphological and phenotypical changes of EMT, with altered levels of adhesion and adherens junction proteins. These changes correlated with impaired cell adhesion and decreased tethering between coupled cells. Impaired E-cadherin-mediated adhesion reduced connexin-43 production and GJIC, these effects being mimicked by neutralisation of E-cadherin ligation. Upregulation of N-cadherin failed to restore adhesion or connexin-43-mediated GJIC. CONCLUSIONS/INTERPRETATION We provide compelling evidence that TGF-β1-induced EMT instigates a loss of E-cadherin, cell adhesion and ultimately of connexin-mediated cell communication in the proximal tubule under diabetic conditions; these changes occur ahead of overt signs of renal damage.
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Affiliation(s)
- C E Hills
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK.
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Morris H, Morgan MD, Wood AM, Smith SW, Ekeowa UI, Herrmann K, Holle JU, Guillevin L, Lomas DA, Perez J, Pusey CD, Salama AD, Stockley R, Wieczorek S, McKnight AJ, Maxwell AP, Miranda E, Williams J, Savage CO, Harper L. ANCA-associated vasculitis is linked to carriage of the Z allele of α₁ antitrypsin and its polymers. Ann Rheum Dis 2011; 70:1851-6. [PMID: 21821620 DOI: 10.1136/ard.2011.153569] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Small studies have linked α1 antitrypsin (α1AT) deficiency to patients with antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV). OBJECTIVE To test the validity and the mechanism of this association between α1AT and AAV. METHODS The distribution of α1AT deficiency alleles Z and S was compared between 856 White Europeans with AAV and 1505 geographic and ethnically matched healthy controls. Genotyping was performed by allelic discrimination assay. RESULTS were compared between cases and controls using χ(2) tests. The serum and renal biopsies for α1AT polymers were compared using the polymer-specific 2C1 antibody. The role of α1AT polymers in promoting inflammation was investigated by examining their ability to prime neutrophils for ANCA activation as assessed by CD62L shedding, superoxide production and myeloperoxidase degranulation. Results The Z but not the S allele was over-represented in the patients compared with controls (HR=2.25, 95% CI 1.60 to 3.19). Higher concentrations of polymers of α1AT were detected in serum from patients carrying the Z allele than in those not carrying the Z allele (median (IQR) 1.40 (0.91-3.32) mg/dl vs 0.17 (0.06-0.28) mg/dl, p<0.001); polymers of α1AT were also seen in the renal biopsy of a patient with vasculitic glomerulonephritis. Polymers of α1AT primed neutrophils with CD62L shedding and increased superoxide production following ANCA activation. Carriage of the Z allele was not associated with disease severity, survival or relapse. CONCLUSIONS The Z but not the S deficiency allele is associated with AAV. Polymers of α1AT are present in the serum and glomeruli of at least some patients with the Z allele, which may promote inflammation through priming of neutrophils.
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Affiliation(s)
- H Morris
- School of Immunity and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
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Thomas SH, Smith SW, Slater NG, Pearson TC, Treacher DF. The haemodynamic responses to venesection and the effects of cardiovascular disease. Clin Lab Haematol 2008; 14:201-8. [PMID: 1451400 DOI: 10.1111/j.1365-2257.1992.tb00366.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The haemodynamic effects of the venesection of one unit (450 ml) of blood over 9 min were measured using non-invasive techniques, in 14 healthy controls and 18 patients with coronary heart disease or hypertension. Venesection was associated with significant reductions in supine and standing systolic and diastolic blood pressure, stroke volume index and cardiac index, and increases in standing heart rate, in both patient groups. No significant differences were observed between the responses of subjects with and without cardiovascular disease. The authors conclude that, in contrast to established teaching, blood loss can be detected in its early stages by careful haemodynamic monitoring and that venesection can be performed safely without volume replacement in patients with stable cardiovascular disease.
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Affiliation(s)
- S H Thomas
- Division of Clinical Pharmacology and Toxicology, United Medical and Dental School, London
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Whitman J, Fronheiser MP, Smith SW. 3-D ultrasound guidance of surgical robotics using catheter transducers: feasibility study. IEEE Trans Ultrason Ferroelectr Freq Control 2008; 55:1143-1145. [PMID: 18519222 DOI: 10.1109/tuffc.2008.766] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The goal of this study was to test the feasibility of using a real-time 3-D (RT3D) ultrasound scanner with matrix array catheter probes to guide a surgical robot. We tested the accuracy of using 3-D catheter transducers with the 3-D measurement software of the scanner to direct automatically a robot arm that touched two needle tips together within a water tank and inside a vascular graft. RMS measurement error ranged from 2.4 to 3.4 mm for two catheter designs.
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Pua EC, Idriss SF, Wolf PD, Smith SW. Real-time three-dimensional transesophageal echocardiography for guiding interventional electrophysiology: feasibility study. Ultrason Imaging 2007; 29:182-194. [PMID: 18092674 DOI: 10.1177/016173460702900304] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
At present, there are limited methods of acquiring three-dimensional visualization of cardiac structure and function in real-time during interventional electrophysiology procedures. Images acquired for integration of computerized tomography and magnetic resonance imaging with electroanatomic mapping systems are static and are obtained earlier in time. The purpose of this study was to test the feasibility of real-time three-dimensional transesophageal echocardiography for the guidance of interventional electrophysiological studies. A matrix array transducer with 504 channels operating at 5 MHz in a 1 cm diameter steerable esophageal probe was used in conjunction with a scanner capable of real-time 3D scanning of pyramidal volumes from 65 degrees to 120 degrees at rates up to 30 volumes per second. This device has a spatial resolution of approximately 3 mm at 5 cm depth. The authors acquired real-time three-dimensional images of anatomic landmarks of value for electrophysiological procedures in five closed chest canines. Real-time, three-dimensional ultrasound imaging was also used for visualization and guidance of interventional catheter devices within the canine heart. Real-time three-dimensional images of the atria, pulmonary veins, and coronary sinus were acquired. Real-time 3-D color flow Doppler was employed to confirm patency. Multiple image planes of image volumes and rendered views were used to track catheter position and orientation. Images of left veno-atrial junctions have been confirmed by dissection. This study has demonstrated the feasiblity of using real-time three-dimensional transesophageal echocardiography for guiding interventional electrophysiology. The technology has the potential to fill a niche as an adjunct modality for cost-effective real-time interventional guidance and assessment, providing catheter and pacing lead visualization simultaneously with functional volumetric cardiac imaging.
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Affiliation(s)
- Eric C Pua
- Department of Mechanical Engineering and Materials Science, Duke University, Box 90300, Durham, NC 27708, USA.
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Abstract
The goal of this research is to determine the feasibility of using a single endoscopic probe for the combined purpose of real-time 3D (RT3D) ultrasound imaging of a target organ and the delivery of ultrasound therapy to facilitate the absorption of compounds for cancer treatment. Recent research in ultrasound therapy has shown that ultrasound-mediated drug delivery improves absorption of treatments for prostate, cervical and esophageal cancer. The ability to combine ultrasound hyperthermia and 3D imaging could improve visualization and targeting of cancerous tissues. In this study, numerical modeling and experimental measurements were developed to determine the feasibility of combined therapy and imaging with a 1 cm diameter endoscopic RT3D probe with 504 transmitters and 252 receive channels. This device operates at 5 MHz and has a 6.3 mm x 6.3 mm aperture to produce real time 3D pyramidal scans of 60-120 degrees incorporating 64 x 64 = 4096 image lines at 30 volumes/sec interleaved with a 3D steerable therapy beam. A finite-element mesh was constructed with over 128,000 elements in LS-DYNA to simulate the induced temperature rise from our transducer with a 3 cm deep focus in tissue. Quarter-symmetry of the transducer was used to reduce mesh size and computation time. Based on intensity values calculated in Field II using the transducer's array geometry, a minimum I(SPTA) of 3.6 W/cm2 is required from our endoscope probe in order to induce a temperature rise of 4 degrees C within five minutes. Experimental measurements of the array's power output capabilities were conducted using a PVDF hydrophone placed 3 cm away from the face of the transducer in a watertank. Using a PDA14 Signatec data acquisition board to capture full volumes of transmitted ultrasound data, it was determined that the probe can presently maintain intensity values up to 2.4 W/cm2 over indefinite times for therapeutic applications combined with intermittent 3D scanning to maintain targeting. These values were acquired using 8 cycle bursts at a prf of 6 kHz. Ex vivo heating experiments of excised pork tissue yielded a maximum temperature rises of 2.3 degrees C over 5 minutes of ultrasound exposure with an average rise of 1.8 +/- 0.2 degrees C over 5 trials. Modifications to the power supply and transducer array may enable us to reach the higher intensities required to facilitate drug delivery therapy.
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Affiliation(s)
- Eric C Pua
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA.
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Smith SW. Paramedic Out-of-hospital Catheterization Laboratory Team Activation for ST-elevation Myocardial Infarction, without Electrocardiogram Transmission, Dramatically Reduces Door-to-balloon Time. Acad Emerg Med 2006. [DOI: 10.1197/j.aem.2006.03.017] [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: 11/10/2022]
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Smith SW. ST-elevation-to-S-wave Ratio Best Identifies Anterior Myocardial Infarction in the Presence of Left Bundle Branch Block. Acad Emerg Med 2006. [DOI: 10.1197/j.aem.2006.03.352] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Smith SW. Incidence of Myocardial Infarction in Emergency Department Chest Pain Patients with a Recent Negative Stress Imaging Test. Acad Emerg Med 2005. [DOI: 10.1197/j.aem.2005.03.138] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Abstract
Transesophageal echocardiography (TEE) is an essential diagnostic tool in patients with poor transthoracic echocardiographic windows or when detailed imaging of structures distant from the chest wall is necessary. A real-time 3D TEE probe has been fabricated in our laboratory in order to increase the amount of information available during a transesophageal procedure. The 1 cm diameter esophageal probe utilizes a 2-dimensional, 5 MHz array at its tip with a 6.3 mm diameter aperture, including 504 active channels. The array has a periodic vernier geometry with an element pitch of 0.18 mm, built onto a multilayer flexible (MLF) interconnect circuit. In order to accommodate 504 channels within the device, a 1 m long Gore MicroFlat cable was utilized for wiring the MLF to the corresponding system connectors. Pulse-echo tests in a water tank have yielded a -6 dB bandwidth of 25.3%. Fully connected to the system through 3 m of cable, the probe shows an average 50 omega insertion loss of-85 dB with a standard deviation of 4 dB, as determined through pitch-catch measurements for a sampling of 10 elements. Using the completed 3D TEE probe with the Volumetrics Medical Imaging 3D scanner, real-time volumetric images of in vivo canine cardiac anatomy have been acquired, displaying atrial views, mitral valve function and interventional catheter guidance.
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Affiliation(s)
- Eric C Pua
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA.
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Chen S, Xianwen C, Dehua X, Zhenguo L, Lingfei X, Smith SW, Zhongcheng Z. Behavioral correction of Parkinsonian rats following the transplantation of immortalized fibroblasts genetically modified with TH and GCH genes. Parkinsonism Relat Disord 2003; 9 Suppl 2:S91-7. [PMID: 12915073 DOI: 10.1016/s1353-8020(03)00020-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Eukaryotic plasmid vectors encoding the tyrosine hydroxylase (TH) gene and GTP cyclohydrolase-1 (GCH) gene were constructed and introduced into immortalized fibroblasts obtained from SV40 large antigen (LT(AG)) transformed rat primary fibroblasts. TH and GCH positive clones were selected and identified by immunohistochemistry and RT-PCR, respectively. Hemi-parkinsonian rats created using 6-hydroxydopamine (6-OHDA) were used to assess the therapeutic effect created by the co-implantation of immortalized fibroblasts genetically modified by TH or GCH genes. Animal behavior was significantly improved two weeks following implantation and behavioral correction was maintained for over 14 weeks. Behavioral improvement was paralleled by exogenous TH gene expression, identified by TH immunohistochemistry and RT-PCR analyses. The transplanted cells survived for at least 38 weeks as demonstrated by fibronectin immunohistochemical staining. Tumor formation or host reaction was not seen, although TH expression was negative for 20 weeks after the implantation. This work demonstrates that the co-transplantation of immortalized fibroblasts genetically modified by TH and GCH genes may be developed as a valuable approach to the treatment of Parkinson's disease.
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Affiliation(s)
- S Chen
- Department of Neurology, Clinical and Research Center for Parkinson Disease, Ruijin Hospital, Shanghai Second Medical University, Shanghai 200025, People's Republic of China.
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Pua EC, Yen JT, Smith SW. Real-time cylindrical curvilinear 3-D ultrasound imaging. Ultrason Imaging 2003; 25:137-150. [PMID: 14870799 DOI: 10.1177/016173460302500302] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In patients who are obese or exhibit signs of pulmonary disease, standard transthoracic scanning may yield poor quality cardiac images. For these conditions, two-dimensional transesophageal echocardiography (TEE) is established as an essential diagnostic tool. Current techniques in transesophageal scanning, though, are limited by incomplete visualization of cardiac structures in close proximity to the transducer. Thus, we propose a 2D curvilinear array for 3D transesophageal echocardiography in order to widen the field of view and increase visualization close to the transducer face. In this project, a 440 channel 5 MHz two-dimensional array with a 12.6 mm aperture diameter on a flexible interconnect circuit has been molded to a 4 mm radius of curvature. A 75% element yield was achieved during fabrication and an average -6dB bandwidth of 30% was observed in pulse-echo tests. Using this transducer in conjunction with modifications to the beam former delay software and scan converter display software of the our 3D scanner, we obtained cylindrical real-time curvilinear volumetric scans of tissue phantoms, including a field of view of greater than 120 degrees in the curved, azimuth direction and 65 degrees phased array sector scans in the elevation direction. These images were achieved using a stepped subaperture across the cylindrical curvilinear direction of the transducer face and phased array sector scanning in the noncurved plane. In addition, real-time volume rendered images of a tissue mimicking phantom with holes ranging from 1 cm to less than 4 mm have been obtained. 3D color flow Doppler results have also been acquired. This configuration can theoretically achieve volumes displaying 180 degrees by 120 degrees. The transducer is also capable of obtaining images through a curvilinear stepped subaperture in azimuth in conjunction with a rectilinear stepped subaperture in elevation, further increasing the field of view close to the transducer face. Future work includes development of an array for adapting these modifications to a 6 mm diameter endoscope probe.
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Affiliation(s)
- E C Pua
- Department of Biomedical Engineering, Duke University, Box 90281, Durham, NC 27705, USA.
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Abstract
Compact electrostatic micromirror structures for use in the scanning arm of an optical coherence tomography (OCT) system are described. These devices consist of millimeter-scale mirrors resting upon micrometer-scale polyimide hinges that are tilted by a linear micromachine actuator, the integrated force array (IFA). The IFA is a network of deformable capacitor cells that electrostatically contract with an applied voltage. The support structures, hinges, and actuators are fabricated by photolithography from polyimide-upon-silicon wafers. These devices were inserted into the scanning arm of an experimental OCT imaging system to produce in vitro and in vivo images at frame rates of 4 to 8 Hz.
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Affiliation(s)
- J M Zara
- Department of Electrical and Computer Engineering, George Washington University, Washington, D.C. 20052, USA.
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Affiliation(s)
- J E Kopfman
- Department of Communication, Cleveland State University, Cleveland, Ohio, USA.
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Zhong ZZ, Schuele DE, Smith SW, Gordon WL. Constitutional isomeric effect on the dielectric relaxation of a nematic liquid crystalline polymethacrylate containing a methoxymethylstilbene side group. Macromolecules 2002. [DOI: 10.1021/ma00076a016] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
OBJECTIVE To compare the efficacy of droperidol with that of prochlorperazine for the treatment of benign headaches in emergency department (ED) patients. METHODS Prospective, randomized clinical trial in an urban ED. Patients were given either droperidol, 5 mg intramuscular (IM) or 2.5 mg intravenous (IV), or prochlorperazine, 10 mg IM or 10 mg IV. Measurements included side effects and the patient's pain perception as measured on a 100-mm visual analog scale (VAS) at baseline, 30, and 60 minutes after the medication was given. Data were analyzed using chi-square, two-tailed t-tests, and two-way analysis of variance (ANOVA) when appropriate. RESULTS During an eight-month period, 168 patients were enrolled. Eighty-two (48.8%) of the patients received droperidol; 86 (51.2%) received prochlorperazine. In the droperidol group, 49 (59.6%) received IM administration and 33 (40.4%) IV. In the prochlorperazine group, 57 (66.3%) received IM administration and 29 (33.7%) IV. Sixty minutes after the medication, the mean decrease in the VAS scores was 81.4% for droperidol and 66.9% for prochlorperazine (p = 0.001). At 30 minutes, 60.9% of the patients receiving droperidol and 44.2% of the patients receiving prochlorperazine had obtained at least a 50% reduction in their VAS scores (p = 0.09). At 60 minutes, 90.2% of the patients receiving droperidol and 68.6% of the patients receiving prochlorperazine had at least a 50% reduction in their VAS scores (p = 0.017). No difference between IM dosing and IV dosing was detected. Side effects, including dystonia, akathisia, and decreased level of consciousness, were seen in 15.2% of the patients receiving droperidol and 9.61% of the patients receiving prochlorperazine. No significant or persisting morbidity was detected. CONCLUSIONS Droperidol was more effective than prochlorperazine in relieving pain associated with benign headaches.
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Affiliation(s)
- J R Miner
- Department of Emergency Medicine, Hennepin County Medical Center, Minneapolis, MN 55415, USA.
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Abstract
Using catheter-mounted 2-D array transducers, we have obtained real-time 3-D intracardiac ultrasound (US) images. We have constructed several transducers with 64 channels inside a 12 French catheter lumen operating at 5 MHz. The transducer configuration may be side-scanning or beveled, with respect to the long axis of the catheter lumen. We have also included six electrodes to acquire simultaneous electrocardiograms. Using an open-chest sheep model, we inserted the catheter into the cardiac chambers to study the utility of in vivo intracardiac 3-D scanning. Images obtained include a cardiac four-chamber view, mitral valve, pulmonic valve, tricuspid valve, interatrial septum, interventricular septum and ventricular volumes. We have also imaged two electrophysiological interventional devices in the right atrium, performed an in vitro ablation study, and viewed the pulmonary veins in vitro.
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Affiliation(s)
- E D Light
- Department of Biomedical Engineering, Duke University, Durham, NC 27708-0281, USA.
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Abstract
Web-based commerce is rife with scenarios where a party needs to trust properties of computation and data storage occurring at a remote machine, operated by a different party with different interests. In our WebALPS project, we have used off-the-shelf hardware and open source software to build
trusted co-servers
co-resident with Web servers, and bring the secure SSL channel all the way into these trusted co-servers. In this paper, we survey how this tool can be used to systematically address privacy and security issues in e-commerce.
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Affiliation(s)
- S. W. Smith
- Department of Computer Science/Institute of Security Technology Studies, Dartmouth College, Hanover, New Hampshire
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Abstract
BACKGROUND 1,4-Butanediol is an industrial solvent that, when ingested, is converted to gamma-hydroxybutyrate, a drug of abuse with depressant effects, primarily on the central nervous system. After reports of toxic effects of gamma-hydroxybutyrate and its resultant regulation by the federal government, 1,4-butanediol and gamma-butyrolactone, another precursor of gamma-hydroxybutyrate and an industrial solvent, began to be marketed as dietary supplements. We investigated reports of toxic effects due to the ingestion of 1,4-butanediol and reviewed the related health risks. METHODS From June 1999 through December 1999, we identified cases of toxic effects of 1,4-butanediol involving patients who presented to our emergency departments with a clinical syndrome suggesting toxic effects of gamma-hydroxybutyrate and a history of ingesting 1,4-butanediol and patients discovered through public health officials and family members. We used gas chromatography-mass spectrometry to measure 1,4-butanediol or its metabolite, gamma-hydroxybutyrate, in urine, serum, or blood. RESULTS We identified nine episodes of toxic effects in eight patients who had ingested 1,4-butanediol recreationally, to enhance bodybuilding, or to treat depression or insomnia. One patient presented twice with toxic effects and had withdrawal symptoms after her second presentation. Clinical findings and adverse events included vomiting, urinary and fecal incontinence, agitation, combativeness, a labile level of consciousness, respiratory depression, and death. No additional intoxicants were identified in six patients, including the two who died. The doses of 1,4-butanediol ingested ranged from 5.4 to 20 g in the patients who died and ranged from 1 to 14 g in the nonfatal cases. CONCLUSIONS The health risks of 1,4-butanediol are similar to those of its counterparts, gamma-hydroxybutyrate and gamma-butyrolactone. These include acute toxic effects, which may be fatal, and addiction and withdrawal.
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Affiliation(s)
- D L Zvosec
- Department of Emergency Medicine, Hennepin County Medical Center, Minneapolis, MN 55415-1829, USA.
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Burris HA, Hainsworth JD, Erland JB, Morrissey LH, Kalman LA, Hon JK, Scullin DC, Smith SW, Greco FA. Phase II trial evaluating triplet chemotherapy using gemcitabine, paclitaxel, and carboplatin in the treatment of patients with advanced non-small cell lung cancer. Semin Oncol 2000; 27:9-13. [PMID: 10697030] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
The purpose of this study was to evaluate the combination of gemcitabine, paclitaxel, and carboplatin in patients with advanced non-small cell lung cancer. Previously untreated patients with stage IIIB or IV non-small cell lung cancer were enrolled into this trial. Sixty-nine patients from the phase II portion and eight patients from the phase I portion were treated with gemcitabine 1,000 mg/m2 intravenously on days I and 8, paclitaxel 200 mg/m2 as a 1-hour infusion on day 1, and carboplatin at an area under the curve of 5.0 intravenously on day 1. Treatment courses were repeated every 21 days. The phase II component of the study was completed at 13 community-based practices in the Minnie Pearl Cancer Research Network. Thirty-four of 71 fully evaluable patients had an objective response (48%, two complete and 32 partial responses). Twenty-five patients (35%) were stable and 12 (17%) progressed. The median response duration was 6 months (range, 3 to 14 months) and the median survival was 9.9 months, with 1- and 2-year survival rates of 47% and 21%, respectively. The combination of gemcitabine, paclitaxel, and carboplatin has been shown to be safe and effective; thus, this three-drug regimen will be compared with a standard two-drug regimen, paclitaxel/carboplatin, in a phase III study.
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Affiliation(s)
- H A Burris
- Sarah Cannon Cancer Center, Nashville, TN 37203, USA
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Fiering JO, Hultman P, Lee W, Light ED, Smith SW. High-density flexible interconnect for two-dimensional ultrasound arrays. IEEE Trans Ultrason Ferroelectr Freq Control 2000; 47:764-770. [PMID: 18238607 DOI: 10.1109/58.842067] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We present a method for fabricating flexible multilayer circuits for interconnection to 2-D array ultrasound transducers. In addition, we describe four 2-D arrays in which such flexible interconnect is implemented, including transthoracic arrays with 438 channels operating at up to 7 MHz and intracardiac catheter arrays with 70 channels operating at up to 7 MHz. We employ thin and thick film microfabrication techniques to batch produce the interconnect circuits with minimum dimensions of 12-mum lines, 40-mum vias, and 150-mum array pitch. The arrays show 50-Omega insertion loss of -60 to -84 dB and a fractional bandwidth of 27 to 67%. The arrays are used to obtain real time, in vivo volumetric scans.
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Zara JM, Bobbio SM, Goodwin-Johansson S, Smith SW. Intracardiac ultrasound scanner using a micromachine (MEMS) actuator. IEEE Trans Ultrason Ferroelectr Freq Control 2000; 47:984-993. [PMID: 18238633 DOI: 10.1109/58.852082] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Catheter-based intracardiac ultrasound offers the potential for improved guidance of interventional cardiac procedures. The objective of this research is the development of catheter-based mechanical sector scanners incorporating high frequency ultrasound transducers operating at frequencies up to 20 MHz. The authors' current transducer assembly consists of a single 1.75 mm by 1.75 mm, 20 MHz, PZT element mounted on a 2 mm by 2 mm square, 75 mum thick polyimide table that pivots on 3-mum thick gold plated polyimide hinges. The hinges also serve as the electrical connections to the transducer. This table-mounted transducer is tilted using a miniature linear actuator to produce a sector scan. This linear actuator is an integrated force array (IFA), which is an example of a micromachine, i.e., a microelectromechanical system (MEMS). The IFA is a thin (2.2 mum) polyimide membrane, which consists of a network of hundreds of thousands of micron scale deformable capacitors made from pairs of metallized polyimide plates. IFAs contract with an applied voltage of 30-120 V and have been shown to produce strains as large as 20% and forces of up to 8 dynes. The prototype transducer and actuator assembly was fabricated and interfaced with a GagePCI analog to digital conversion board digitizing 12 bit samples at a rate of 100 MSamples/second housed in a personal computer to create a single channel ultrasound scanner. The deflection of the table transducer in a low viscosity insulating fluid (HFE 7100, 3M) is up to +/-10 degrees at scan rates of 10-60 Hz. Software has been developed to produce real-time sector scans on the PC monitor.
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Affiliation(s)
- J M Zara
- Dept. of Biomed. Eng., Duke Univ., Durham, NC
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Yen JT, Steinberg JP, Smith SW. Sparse 2-D array design for real time rectilinear volumetric imaging. IEEE Trans Ultrason Ferroelectr Freq Control 2000; 47:93-110. [PMID: 18238521 DOI: 10.1109/58.818752] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Several sparse 2-D arrays for real time rectilinear volumetric imaging were investigated. All arrays consisted of 128x128=16,384 elements with lambda spacing operating at 5 MHz. Because of system limitations, not all of the elements could be used. From each array, 256 elements were used as transmitters, and 256 elements were used as receivers. These arrays were compared by computer simulation using Field II. For each array, beamplots for the on-axis case and an illustrative off-axis case were obtained. For the off-axis case, the effects of receive mode dynamic focusing were studied to maintain the beam perpendicular to the transducer face. Main lobe widths, side lobe heights, clutter floor levels, and pulse-echo sensitivities were quantified for each array. The sparse arrays, including a vernier periodic array, a random array, and a Mills cross array, were compared with a fully sampled array that served as the "gold standard". The Mills cross design showed the best overall performance under the current system constraints.
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Affiliation(s)
- J T Yen
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA.
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Smith SW, Connery P, Knudsen K, Scott KL, Frintner MP, Outlaw G, Weingart S. A preschool immunization project to enhance immunization levels, the public-private relationship, and continuity of care. J Community Health 1999; 24:347-58. [PMID: 10555924 DOI: 10.1023/a:1018782219897] [Citation(s) in RCA: 4] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
This study was conducted to determine whether implementing a program aimed at providing a variety of incentives to physicians who provide immunizations to preschool-aged children would help to improve immunization rates and reduce fragmented care for patients. Twenty physicians from 14 private practices that provide care to preschool-aged children from low income families in suburban Cook County, Illinois participated in the project. A randomly selected subset of patient case records from the physicians' offices were audited after the implementation of the project to determine the immunization status of children in the practices and the nature of services provided. These 310 records of children under three years of age who were treated between 1991-1994 (the intervention sample) were compared to 310 charts from a 1988-1990 cohort of records (baseline sample). The groups did not differ on race or gender; however, significantly more families in the 1988 through 1990 cohort of children under 3 years of age were insured privately when compared to the 1991 through 1994 cohort. Seventy percent (218) of the records in the intervention sample were up to date for age on immunizations compared to 45% (141) of the baseline records, reflecting a statistically significant difference (p < .00001). The intervention sample showed significantly more well child visits where immunizations were given and follow up visits where immunizations were given when compared to the baseline sample. Physicians completed surveys before and after implementation of the project. They were questioned about their knowledge and practices regarding immunizations as well as their opinion of specific project components. All of the physicians viewed the project as an effective means to improve immunization services to low income children. The project demonstrates a potential means of enhancing immunization levels and continuity of care among preschool-aged children. It also highlights the workable nature of the partnership between public and private sectors.
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Affiliation(s)
- S W Smith
- Cook County Department of Public Health, Oak Park, Illinois 60301, USA
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Affiliation(s)
- S W Smith
- Department of Emergency Medicine, Hennepin County Medical Center, and the University of Minnesota School of Medicine, Minneapolis, USA
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Abstract
OBJECTIVES To assess the impact of surgically placed feeding tubes on children with severe cerebral palsy (CP) and their families and to determine the survival of these children after initiation of tube feeding (TF). METHODS Virtually all children from Nova Scotia who had gastrostomy or jejunostomy procedures between the years 1980 and 1998 and who had been diagnosed with CP were identified. Caretakers of those children who had TF initiated in the last 8 years were evaluated by using a semi-structured interview. Names of children who had not had recent follow-up visits were submitted to the provincial Vital Statistics office to determine whether they had died. Data from patients who were tube-fed between 1980 and 1989 were then used in combination with data from the more recent cases to create a survival curve. RESULTS A total of 61 children were identified; 16 had died. Forty of 45 eligible families were interviewed; 90% were pleased with the effect of TF on their child and family life. Negative reports were associated with increased stress related to feeding. Survival rates after gastrostomy and/or jejunostomy were 83% after 2 years and 75% after 7 years. CONCLUSIONS In children with severe CF, initiation of TF improved the quality of life for both the child and family in 90% despite frequent minor complications.
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Affiliation(s)
- S W Smith
- Dalhousie University Medical School and IWK-Grace Health Centre, Department of Pediatrics, Dalhousie University, Halifax, Nova Scotia, Canada
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Abstract
The use of distraction osteogenesis offers an alternative approach to the correction of craniofacial deformities. However, little is known with respect to the appropriate length of the consolidation period for the newly formed bone. The objective of this study was to evaluate, by quantitative computed tomography, the regenerate bone produced during osteodistraction of the dog mandible at three different consolidation times. Twelve skeletally mature male beagle dogs were equally separated into three experimental groups. Each dog underwent 10 mm of bilateral distraction osteogenesis to lengthen the mandible. After the distraction period, the bone was allowed to consolidate for 4, 6, or 8 weeks, at which time the animals were sacrificed and the mandibles harvested for computed tomographic imaging. The results demonstrate a significantly lower mean bone density of the regenerate in the 4 week group when compared with either the 6 or 8 week groups (P < .01). There was no significant difference, however, in mean bone density between the 6 and 8 week groups.
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Affiliation(s)
- S W Smith
- Department of Orthodontics, Texas A&M University System-Baylor College of Dentistry, Texas, USA
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Smith SW, English JD. Orthodontic correction of a class III malocclusion in an adolescent patient with a bonded RPE and protraction face mask. Am J Orthod Dentofacial Orthop 1999; 116:177-83. [PMID: 10434091 DOI: 10.1016/s0889-5406(99)70215-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [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: 11/17/2022]
Abstract
A case report of a 14-year-old Hispanic male with a Class-III skeletal profile and dental malocclusion with a long mandibular body and ramus and retrusive maxilla. The patient was initially referred for a surgical evaluation for a LeFort I maxillary advancement, but he wanted to avoid surgery. The Class-III malocclusion was corrected with a bonded rapid palatal expander and a maxillary protraction mask followed by nonextraction orthodontic treatment. A Class-I molar and canine relationship was achieved, and the facial profile improved. This case report demonstrates the orthodontic correction of a Class-III malocclusion in an adolescent patient with a bonded rapid palatal expander and protraction face mask. This case was presented to American Board of Orthodontics as partial fulfillment of the requirements for the certification process conducted by the Board.
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Affiliation(s)
- S W Smith
- Department of Orthodontics, Baylor College of Dentistry, Dallas, Texas 75266-0677, USA
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Smith SW. Re: Viscosity of helium. J Emerg Med 1999; 17:745. [PMID: 10431974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
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Hainsworth JD, Burris HA, Erland JB, Morrissey LH, Meluch AA, Kalman LA, Hon JK, Scullin DC, Smith SW, Greco FA. Phase I/II trial of paclitaxel by 1-hour infusion, carboplatin, and gemcitabine in the treatment of patients with advanced nonsmall cell lung carcinoma. Cancer 1999; 85:1269-76. [PMID: 10189131 DOI: 10.1002/(sici)1097-0142(19990315)85:6<1269::aid-cncr8>3.0.co;2-i] [Citation(s) in RCA: 32] [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: 11/07/2022]
Abstract
BACKGROUND The combination of paclitaxel and carboplatin is widely used in the treatment of patients with advanced nonsmall cell lung carcinoma. In this Phase I/II study the authors evaluated the feasibility, toxicity, and efficacy of adding a third active antineoplastic agent, gemcitabine, to the paclitaxel/carboplatin combination for the treatment of patients with advanced nonsmall cell lung carcinoma. METHODS Patients with advanced (AJCC Stage IIIB or IV) nonsmall cell lung carcinoma previously untreated with chemotherapy were eligible for this trial. The maximum tolerated doses, determined in the Phase I trial and subsequently used in the Phase II trial, were: paclitaxel, 200 mg/m2, as a 1-hour infusion on Day 1; carboplatin, at area under the curve dose of 5.0 intravenously (i.v.), on Day 1; and gemcitabine, 1000 mg/m2 i.v., on Days 1 and 8. Treatment courses were repeated every 21 days. The Phase II study was conducted in 13 community-based practices in the Minnie Pearl Cancer Research Network; 77 patients were treated between December 1996 and September 1997. RESULTS Thirty-four of 77 patients (44%) in the Phase II trial had major responses (partial responses, 32 patients and complete responses, 2 patients). An additional 25 patients (33%) had stable disease or minor response; only 23% of patients progressed or were removed from study at or prior to first reevaluation. The median survival was 9.4 months, with a 45% actuarial 1-year survival rate. Myelosuppression was the most common toxicity, with Grade 3/4 NCI Common Toxicity Criteria leukopenia and thrombocytopenia in 49% and 45% of patients, respectively. However, only 11 patients (14%) required hospitalization for neutropenia/ fever, and none had bleeding complications. Grade 3/4 nonhematologic toxicities included fatigue (41%), arthralgias/myalgias (26%), peripheral neuropathy (8%), nausea/emesis (6%), and hypersensitivity reactions (4%). There was one treatment-related death due to sepsis. CONCLUSIONS This three-drug regimen is active and has acceptable toxicity in patients with advanced nonsmall cell lung carcinoma. Myelosuppression, particularly thrombocytopenia, is increased in comparison to the paclitaxel/carboplatin regimen. Fatigue also may be increased, but other nonhematologic toxicities are not altered substantially by adding gemcitabine. Although the response rate and median survival are improved modestly compared with our previous experience with paclitaxel/carboplatin, definitive conclusions regarding the efficacy of this regimen await the completion of randomized trials.
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Affiliation(s)
- J D Hainsworth
- Sarah Cannon-Minnie Pearl Cancer Center, Nashville, Tennessee 37203, USA
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