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Anderson AC, Menon M, Cohen SA, Hannan L, Safyan R, Chiorean EG, Schouten J, Apisarnthanarax S, Kim EY. Clinical Outcomes and Immunotoxicity in People with HIV (PWH) after Definitive Chemoradiation (CRT) for Anal Squamous Cell Carcinoma. Int J Radiat Oncol Biol Phys 2023; 117:e282-e283. [PMID: 37785053 DOI: 10.1016/j.ijrobp.2023.06.1266] [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] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Anal cancer disproportionately affects PWH despite antiretroviral therapy. Data on CRT outcomes are limited. Modern IMRT CRT decreases acute toxicity but may exacerbate immune dysregulation from chronic HIV. Although historical CRT has been associated with prolonged CD4 count suppression, little is known about late immunotoxicity in PWH after contemporary CRT. We report clinical outcomes and long term immunotoxicity. MATERIALS/METHODS Single-center retrospective review of all PWH confirmed on chart review with anal squamous cell carcinoma without prior pelvic irradiation treated with definitive IMRT CRT. Patient and CRT factors including HIV suppression (<200 copies/mL), mean CD4 count (cells/µL), and receipt of capecitabine (C) or 5-fluorouracil (F) +/- mitomycin (M) were summarized with n (%) or median (interquartile range). Progression-free and overall survival (PFS; OS) were estimated per Kaplan-Meier with 95% confidence intervals and compared with log-rank tests. Mean CD4 count and CD4:CD8 were compared by HIV suppression status (Welch's t-test); longitudinal changes in median CD4 count and CD4:CD8 were compared between baseline vs. nadir (within 6 months of CRT start) and 1-year follow-up for patients with complete data (Wilcoxon signed-rank test). RESULTS A total of 23 PWH were treated between 2010-2022, median age 52, median 16 (13 - 19) years after HIV diagnosis; 4 had unsuppressed HIV; AJCC 8th stage I/II/III/IV 5/5/12/1. Radiation dose was median 54 Gy in 30 fractions over 42 (40 - 44) days. Most had C+M (57%); only 43% had 2×M with either C or F. One had neoadjuvant carboplatin/paclitaxel/pembrolizumab. With 2.9 (1.03 - 3.3) years follow-up, median OS was 6.6 (6.2 - unreached [UR]) years. With 2.2 (0.67 - 2.7) years follow-up, median PFS was UR. OS and PFS were similar regardless of HIV suppression status (both P ≥ 0.09). Overall baseline CD4 count was 458 (226 - 484), and CD4:CD8 was 0.54 (0.2 - 0.7). Nadir CD4 was 100 (59 - 126) and CD4:CD8 was 0.3 (0.2 - 0.4). Baseline and nadir CD4 count and CD4:CD8 were lower if HIV-unsuppressed (each P ≤ 0.04). One year after CRT, CD4 count was 252 (102 - 276), while CD4:CD8 was 0.5 (0.2 - 0.7). For 7 patients with repeated values the change in median from baseline to nadir, 6-, and 12-months post-CRT was -282, -549 (both P = 0.02), -480 (P = 0.9) for CD4 counts, and -0.7, -0.5, -0.4 (each P > 0.5) for CD4:CD8 ratios; none had unsuppressed HIV. CONCLUSION Definitive IMRT CRT with guideline-concordant doublet chemotherapy for anal cancer in PWH is effective despite unsuppressed HIV. Treatment leads to prolonged immunological changes that may increase the risk of HIV-related morbidity and mortality. Modifiable treatment-related causes of hematoimmunologic toxicity should be investigated further, and immune surveillance after CRT should be considered to better understand impact on quality of life.
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Affiliation(s)
- A C Anderson
- Department of Radiation Oncology, University of Washington/ Fred Hutchinson Cancer Center, Seattle, WA
| | - M Menon
- Division of Hematology, Department of Medicine, University of Washington/ Fred Hutchinson Cancer Center, Seattle, WA
| | - S A Cohen
- Division of Oncology, Department of Medicine, University of Washington/ Fred Hutchinson Cancer Center, Seattle, WA
| | - L Hannan
- Division of Oncology, Department of Medicine, University of Washington/ Fred Hutchinson Cancer Center, Seattle, WA
| | - R Safyan
- Division of Oncology, Department of Medicine, University of Washington/ Fred Hutchinson Cancer Center, Seattle, WA
| | - E G Chiorean
- Division of Oncology, Department of Medicine, University of Washington/ Fred Hutchinson Cancer Center, Seattle, WA
| | - J Schouten
- Division of Allergy & Infectious Diseases, Department of Medicine, University of Washington/ Fred Hutchinson Cancer Center, Seattle, WA
| | - S Apisarnthanarax
- Department of Radiation Oncology, University of Washington/ Fred Hutchinson Cancer Center, Seattle, WA
| | - E Y Kim
- Department of Radiation Oncology, University of Washington/ Fred Hutchinson Cancer Center, Seattle, WA
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Galea CA, Swanson CPS, Cohen SA, Thomas SJ. Use of a Mylar filter to eliminate vacuum ultraviolet pulse pileup in low-energy x-ray measurements. Rev Sci Instrum 2022; 93:093531. [PMID: 36182492 DOI: 10.1063/5.0101712] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 08/15/2022] [Indexed: 06/16/2023]
Abstract
We describe a method to reduce vacuum ultraviolet (VUV) pulse pileup (PPU) in x-ray pulse-height Silicon Drift Detector (SDD) signals. An Amptek FAST SDD, with C1 (Si3N4) window, measures bremsstrahlung emitted from PFRC-2 plasma to extract the electron temperature (Te) and density (ne). The C1 window has low transmissivity for photons with energy below 200 eV though will transmit some VUV and soft x-ray photons, which PFRC-2 plasmas abundantly emit. Multi-VUV-photon PPU contaminates the interpretation of x rays with energy > 100 eV, particularly in a low-energy exponential tail. The predicted low transmissivity of ∼1 μm thick Mylar [polyethylene terephthalate (PET)] to photons of energy <100 eV led to the selection of Mylar as the candidate filter to reduce VUV PPU. Experiments were conducted on an x-ray tube with a graphite target and on a quasi-Maxwellian tenuous plasma (ne ∼ 109 cm-3) with effective temperatures reaching 1500 eV. A Mylar filter thickness of 850 nm is consistent with the results. The Mylar-filter-equipped SDD was then used on the PFRC-2 plasma, showing a substantial reduction in the low-energy x-ray signal, supporting our hypothesis of the importance of VUV PPU. We describe the modeling and experiments performed to characterize the effect of the Mylar filter on SDD measurements.
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Affiliation(s)
- C A Galea
- Princeton Fusion Systems, Plainsboro, New Jersey 08536, USA
| | - C P S Swanson
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - S A Cohen
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - S J Thomas
- Princeton Fusion Systems, Plainsboro, New Jersey 08536, USA
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Dogariu A, Cohen SA, Jandovitz P, Vinoth S, Evans ES, Swanson CPS. A diagnostic to measure neutral-atom density in fusion-research plasmas. Rev Sci Instrum 2022; 93:093519. [PMID: 36182459 DOI: 10.1063/5.0101683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 08/16/2022] [Indexed: 06/16/2023]
Abstract
A femtosecond two-photon-absorption laser-induced-fluorescence (TALIF) diagnostic was designed, installed, and operated on the Princeton-Field-Reversed Configuration-2 device to provide non-invasive measurements of the time and spatially resolved neutral-atom densities in its plasmas. Calibration of the Ho density was accomplished by comparison with Kr TALIF. Measurements on plasmas formed of either H2 or Kr fill gases allowed examination of nominally long and short ionization mean-free-path regimes. With multi-kW plasma heating and H2 fill gas, a spatially uniform Ho density of order 1017 m-3 was measured with better than ±2 mm and 10 µs resolution. Under similar plasma conditions but with Kr fill gas, a 3-fold decrease in the in-plasma Kr density was observed.
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Affiliation(s)
- A Dogariu
- Mechanical and Aerospace Engineering Department, Princeton University, Princeton, New Jersey 08540, USA
| | - S A Cohen
- Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543, USA
| | - P Jandovitz
- Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543, USA
| | - S Vinoth
- Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543, USA
| | - E S Evans
- Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543, USA
| | - C P S Swanson
- Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543, USA
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Vinoth SP, Evans ES, Swanson CPS, Palmerduca E, Cohen SA. Evaluation of a collisional radiative model for electron temperature determination in hydrogen plasma. Rev Sci Instrum 2022; 93:093503. [PMID: 36182465 DOI: 10.1063/5.0101676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 07/29/2022] [Indexed: 06/16/2023]
Abstract
A collisional-radiative (CR) model that extracts the electron temperature, Te, of hydrogen plasmas from Balmer-line-ratio measurements is examined for the plasma electron density, ne, and Te ranges of 1010-1015 cm-3 and 5-500 eV, respectively. The CR code, developed and implemented in Python, has a forward component that computes the densities of excited states up to n = 15 as functions of Te, ne, and the molecular-to-atomic neutral ratio r(H2/H). The backward component provides ne and r(H2/H) as functions of the Balmer ratios to predict the Te. The model assumes Maxwellian electrons. The density profiles of the electrons and of the molecular and atomic hydrogen neutrals are shown to be of great importance, as is the accuracy of the line-ratio measurement method.
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Affiliation(s)
- S P Vinoth
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - E S Evans
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - C P S Swanson
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - E Palmerduca
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
| | - S A Cohen
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
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Glasser AH, Cohen SA. Simulating single-particle dynamics in magnetized plasmas: The RMF code. Rev Sci Instrum 2022; 93:083506. [PMID: 36050065 DOI: 10.1063/5.0101665] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 06/30/2022] [Indexed: 06/15/2023]
Abstract
The RMF (Rotating Magnetic Field) code is designed to calculate the motion of a charged particle in a given electromagnetic field. It integrates Hamilton's equations in cylindrical coordinates using an adaptive predictor-corrector double-precision variable-coefficient ordinary differential equation solver for speed and accuracy. RMF has multiple capabilities for the field. Particle motion is initialized by specifying the position and velocity vectors. The six-dimensional state vector and derived quantities are saved as functions of time. A post-processing graphics code, XDRAW, is used on the stored output to plot up to 12 windows of any two quantities using different colors to denote successive time intervals. Multiple cases of RMF may be run in parallel and perform data mining on the results. Recent features are a synthetic diagnostic for simulating the observations of charge-exchange-neutral energy distributions and RF grids to explore a Fermi acceleration parallel to static magnetic fields.
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Affiliation(s)
- A H Glasser
- Fusion Theory & Computation, Inc., 24062 Seatter Lane Nebraska, Kingston, Washington 98346, USA
| | - S A Cohen
- Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543, USA
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Xu F, Cohen SA, Lofgren IE, Greene GW, Delmonico MJ, Greaney ML. The Association between Physical Activity and Metabolic Syndrome in Older Adults with Obesity. J Frailty Aging 2019; 8:27-32. [PMID: 30734828 DOI: 10.14283/jfa.2018.34] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Physical activity reduces the likelihood of developing metabolic syndrome (MetS). However, the association between different physical activity levels and MetS remains unclear in older adults with obesity. METHODS This cross-sectional study used four waves of data (2007-2008, 2009-2010, 2011-2012, 2013-2014) from two datasets: The National Health and Nutrition Examination Survey and United Sates Department of Agriculture's Food Patterns Equivalents Database. The sample included adults 60+ years of age (n= 613) with obesity who had physical activity and MetS data. Physical activity was assessed using the Global Physical Activity Questionnaire and categorized into three physical activity levels (low, medium, and high); and medium or high physical activity levels are aligned with or exceed current physical activity recommendations. Participants were classified as having MetS using a commonly agreed upon definition. Multiple logistic regression models examined the association between the three physical activity levels and MetS risk factors and MetS. All analyses adjusted for potential confounding variables and accounted for complex sampling. RESULTS Of 613 respondents, 72.1% (n=431) were classified as having MetS, and 44.3% (n = 263) had not met physical activity recommendations. Participants with high levels of physical activity had a lower risk of MetS (OR = 0.31, 95%CI: 0.13, 0.72) and more healthful levels of high-density lipoprotein cholesterol (OR = 0.39, 95%CI: 0.18, 0.84), blood pressure (OR = 0.39, 95%CI: 0.20, 0.77), fasting glucose (OR = 0.34, 95%CI: 0.15, 0.78) than participants categorized as having low physical activity. CONCLUSIONS Physical activity is associated with lower risk of MetS only for participants with the highest level of physical activity, which suggests that physical activity dosage is important to reduce MetS risk in older adults with obesity.
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Affiliation(s)
- F Xu
- Furong Xu, PhD, Department of Kinesiology, 25 West Independence Way, Suite P, The University of Rhode Island, Kingston, RI 02881,
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Xu F, Cohen SA, Lofgren IE, Greene GW, Delmonico MJ, Greaney ML. Relationship between Diet Quality, Physical Activity and Health-Related Quality of Life in Older Adults: Findings from 2007-2014 National Health and Nutrition Examination Survey. J Nutr Health Aging 2018; 22:1072-1079. [PMID: 30379305 DOI: 10.1007/s12603-018-1050-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
BACKGROUND A growing body of research shows that diet quality and physical activity (PA) are associated with health-related quality of life (HRQOL). However, no study to date has assessed this association using the Healthy Eating Index-2015 as a measure of diet quality. Furthermore, few studies have examined the association between PA dose and HRQOL among a nationally representative sample of older adults. OBJECTIVES To investigate the relationship between diet quality, physical activity, and HRQOL. DESIGN A cross-sectional analysis was conducted using data obtained from 5,311 adults aged 60+ years who took part in the National Health and Nutrition Examination Survey between 2007 and 2014. MEASUREMENTS HRQOL was assessed by general health status, and number of physically unhealthy days, mentally unhealthy days, and inactive days in past 30 days. Diet quality was assessed by the Healthy Eating Index-2015 using data generated by two 24-hour dietary recalls. PA was measured by the Global Physical Activity Questionnaire. Multivariate logistic/or linear regression models were used to examine the association between diet quality, PA and HRQOL controlling for confounders and accounting for complex sampling. RESULTS Approximately half of the participants (55.2%) were women, 45.1% met current PA recommendations, 65% had less healthful diets according to the Healthy Eating Index-2015. Diet quality was associated with HROQL. For every 1-point diet quality score increase, the likelihood of respondents rating their general health as being excellent/good increased by 3% (OR=1.03, 95%CI: 1.02, 1.04), and number of inactive days (β =-0.03, 95%CI: -0.05, 0.00) and mental unhealthy days (β =-0.03, 95%CI: -0.05, -0.01) declined by 0.03 days. PA was associated with all HROQL measures and respondents with high PA levels reported better general health (OR=3.53, 95%CI: 2.69, 4.63), fewer inactive days (β =-1.53, 95%CI: -2.11, -0.95), fewer physical unhealthy days (β =-1.88, 95%CI: -2.74, -1.02) than individuals with low PA levels but not fewer mentally unhealthy days. CONCLUSIONS Among older adults in this study, eating a healthier diet and being physically active were associated with better general health and reporting fewer physical unhealthy days and inactive days. Study results provide valuable information that could inform policies, programs and interventions designed to improve HRQOL in older adults and reduce potentially preventable health disparities.
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Affiliation(s)
- F Xu
- Furong Xu, PhD, Department of Kinesiology, 25 West Independence Way, Suite P, The University of Rhode Island, Kingston, RI 02881,
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Myers CE, Edwards MR, Berlinger B, Brooks A, Cohen SA. Passive Superconducting Flux Conservers for Rotating-Magnetic-Field-Driven Field-Reversed Configurations. Fusion Science and Technology 2017. [DOI: 10.13182/fst12-a13341] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- C. E. Myers
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543
| | - M. R. Edwards
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543
| | - B. Berlinger
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543
| | - A. Brooks
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543
| | - S. A. Cohen
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543
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Cohen SA, Woodfield MC, Boyle N, Stednick Z, Boeckh M, Pergam SA. Incidence and outcomes of bloodstream infections among hematopoietic cell transplant recipients from species commonly reported to be in over-the-counter probiotic formulations. Transpl Infect Dis 2016; 18:699-705. [PMID: 27501401 DOI: 10.1111/tid.12587] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 05/23/2016] [Accepted: 06/05/2016] [Indexed: 12/19/2022]
Abstract
BACKGROUND Probiotic supplementation has been promoted for numerous health conditions; however, safety in immunosuppressed patients is unknown. We evaluated bloodstream infections (BSIs) caused by common probiotic organisms in hematopoietic cell transplant recipients. METHODS All blood culture (BC) results from a cohort of hematopoietic cell transplant recipients transplanted at Fred Hutchinson Cancer Research Center in Seattle, Washington, between 2002 and 2011 were reviewed. Patients with at least 1 positive BC for common probiotic organisms (Lactobacillus species, Bifidobacterium species, Streptococcus thermophilus, and Saccharomyces species) within 1 year post hematopoietic cell transplantation (HCT) were considered cases. Data were collected from center databases, which contain archived laboratory data, patient demographics, and clinical summaries. RESULTS A total of 19/3796 (0.5%) patients developed a BSI from one of these organisms within 1 year post HCT; no Bifidobacterium species or S. thermophilus were identified. Cases had a median age of 49 years (interquartile range [IQR]: 39-53), and the majority were allogeneic hematopoietic cell transplant recipients (14/19, 74%). Most positive BCs were Lactobacillus species (18/19) and occurred at a median of 84 days (IQR: 34-127) post transplant. The incidence rate of Lactobacillus bacteremia was 1.62 cases per 100,000 patient-days; the highest rate occurred within 100 days post transplant (3.3 per 100,000 patient-days). Eight patients (44%) were diagnosed with acute graft-versus-host disease of the gut prior to the development of bacteremia. No mortality was attributable to any of these infections. CONCLUSION Organisms frequently incorporated in available over-the-counter probiotics are infrequent causes of bacteremia after HCT. Studies evaluating the use of probiotics among high-risk patients are needed.
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Affiliation(s)
- S A Cohen
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.,Department of Medicine, University of Washington, Seattle, Washington, USA
| | - M C Woodfield
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - N Boyle
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Z Stednick
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - M Boeckh
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.,Department of Medicine, University of Washington, Seattle, Washington, USA
| | - S A Pergam
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA. .,Department of Medicine, University of Washington, Seattle, Washington, USA. .,Infection Prevention, Seattle Cancer Care Alliance, Seattle, Washington, USA.
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Zierhut HA, Shannon KM, Cragun DL, Cohen SA. Elucidating Genetic Counseling Outcomes from the Perspective of Genetic Counselors. J Genet Couns 2016; 25:993-1001. [DOI: 10.1007/s10897-015-9930-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 12/20/2015] [Indexed: 12/01/2022]
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Wurden GA, Weber TE, Turchi PJ, Parks PB, Evans TE, Cohen SA, Cassibry JT, Campbell EM. A New Vision for Fusion Energy Research: Fusion Rocket Engines for Planetary Defense. J Fusion Energ 2015. [DOI: 10.1007/s10894-015-0034-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Abstract
We argue that it is essential for the fusion energy program to identify an imagination-capturing critical mission by developing a unique product which could command the marketplace. We lay out the logic that this product is a fusion rocket engine, to enable a rapid response capable of deflecting an incoming comet, to prevent its impact on the planet Earth, in defense of our population, infrastructure, and civilization. As a side benefit, deep space solar system exploration, with greater speed and orders-of-magnitude greater payload mass would also be possible.
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Cohen SA, Juwono T, Palazzi KL, Kaplan GW, Chiang G. Examining trends in the treatment of ureterocele yields no definitive solution. J Pediatr Urol 2015; 11:29.e1-6. [PMID: 25459387 DOI: 10.1016/j.jpurol.2014.09.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 09/21/2014] [Indexed: 10/24/2022]
Abstract
INTRODUCTION The surgical management of ureteroceles is extremely variable. Some have hypothesized that if these patients were treated with 'definitive' staged surgical intervention, the need for further revision surgery would be eliminated. OBJECTIVE The present study sought to determine if the rate of revision surgery differed among patients who have undergone different surgical approaches for the ureterocele complex. STUDY DESIGN A large retrospective chart review was conducted, identifying all patients having undergone ureterocele surgery at a single institution over the past 41 years. The cohort was divided into four groups based on surgical approach: upper tract approach (UTA), lower tract reconstruction (LTR), simultaneous upper and lower tract approach (ULTA), and staged lower tract reconstruction (SLTR). Demographics, the presence of preoperative/postoperative VUR, postoperative morbidity and the need for revision surgery were compared using the Chi- squared test, Fisher's exact test, Kruskal-Wallis test, Mann-Whitney U test (Bonferroni correction), logistic regression modeling and survival analyses (Kaplan-Meier and Cox proportional Hazards regression with unplanned revision operation as the outcome event). RESULTS Between 1969 and 2010, 180 patients were identified as having undergone surgical management of ureteroceles, of which 120 had complete demographic data available for analysis. The median age at the time of initial surgical intervention was 5.8 months and the majority of patients (83.3%) were female. The median follow-up was 33.1 months. Surgical management was as follows: 18 (15.0%) patients underwent UTA, 47 (39.2%) underwent LTR, 23 (19.2%) underwent ULTA, and 32 (26.6%) underwent SLTR. Among these groups, the only difference in median age was between the LTR and SLTR groups (6.3 months vs 3.7 months, P=0.012). Additional revision surgery was required in: nine (50.0%) of UTA, ten (21.3%) of LTR, four (17.4%) of ULTA, and three (9.4%) of SLTR. The only statistically significant difference in unplanned revision surgery was noted in the UTA group versus each of the other groups with VUR as the predominant indication (88.9%). The likelihood of requiring revision surgery in comparison to the SLTR group was significantly increased in the UTA group (OR 9.67, CI 2.15-43.56), but not in the LTR (OR 2.61, CI 0.66-10.37) or the ULTA group (OR 2.04, CI 0.41-10.13). Obstruction, recurring UTIs and VUR were the main indications for revision surgery overall. DISCUSSION There is a large body of literature examining the surgical management of ureteroceles. It most recently primarily focuses on an endoscopic approach to the lower tract. The present retrospective review examined the need for re-operative intervention by comparing four different surgical approaches, and found that there is no panacea. Although heminephrectomy (UTA) was a definitive procedure in some patients without reflux at presentation, many who underwent heminephrectomy, went on to require later bladder surgery for either recurrent UTI or persistent reflux. The present study has multiple limitations. Although VUR was an indication for revision surgery in the early part of the series, the current treatment of VUR is not necessarily as stringent. In addition, no distinction was made between an orthotopic or ectopic ureterocele, although some authors have reported differing outcomes in these two groups. However, it is felt that given the large data set of a relatively uncommon condition, the lack of superiority of one approach is apparent. CONCLUSION There is no definitive surgical repair for the ureterocele complex. All groups except UTA had statistically similar rates of revision surgery. The widespread variability in current management echoes the lack of one superior approach found in this comprehensive series.
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Affiliation(s)
- S A Cohen
- Department of Urology, UC San Diego Health System, 200 West Arbor Dr. #8897, San Diego, CA 92103-8897, USA
| | - T Juwono
- Department of Urology, UC San Diego Health System, 200 West Arbor Dr. #8897, San Diego, CA 92103-8897, USA
| | - K L Palazzi
- Department of Urology, UC San Diego Health System, 200 West Arbor Dr. #8897, San Diego, CA 92103-8897, USA
| | - G W Kaplan
- Department of Urology, UC San Diego Health System, 200 West Arbor Dr. #8897, San Diego, CA 92103-8897, USA; Pediatric Urology, Rady Children's Hospital-San Diego, 3020 Children's Way, MC 5056, San Diego, CA 92123, USA
| | - G Chiang
- Department of Urology, UC San Diego Health System, 200 West Arbor Dr. #8897, San Diego, CA 92103-8897, USA; Pediatric Urology, Rady Children's Hospital-San Diego, 3020 Children's Way, MC 5056, San Diego, CA 92123, USA.
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Peterson BM, Grier CJ, Horne K, Pogge RW, Bentz MC, De Rosa G, Denney KD, Martini P, Sergeev SG, Kaspi S, Minezaki T, Zu Y, Kochanek CS, Siverd RJ, Shappee B, Araya Salvo C, Beatty TG, Bird JC, Bord DJ, Borman GA, Che X, Chen CT, Cohen SA, Dietrich M, Doroshenko VT, Drake T, Efimov YS, Free N, Ginsburg I, Henderson CB, King AL, Koshida S, Mogren K, Molina M, Mosquera AM, Motohara K, Nazarov SV, Okhmat DN, Pejcha O, Rafter S, Shields JC, Skowron DM, Skowron J, Valluri M, van Saders JL, Yoshii Y. REVERBERATION MAPPING OF THE SEYFERT 1 GALAXY NGC 7469. ACTA ACUST UNITED AC 2014. [DOI: 10.1088/0004-637x/795/2/149] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Berlinger B, Brooks A, Feder H, Gumbas J, Franckowiak T, Cohen SA. Use of Polycarbonate Vacuum Vessels in High-Temperature Fusion-Plasma Research. Fusion Science and Technology 2013. [DOI: 10.13182/fst13-a18093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- B. Berlinger
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543
| | - A. Brooks
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543
| | - H. Feder
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543
| | - J. Gumbas
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543
| | - T. Franckowiak
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543
| | - S. A. Cohen
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543
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Hughes GR, Cohen SA, Christian C. Anti-DNA activity in systemic lupus erythematosus. Isr Med Assoc J 2011; 13:273. [PMID: 21845966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
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Cohen SA, Liu J, Gignac L, Ivers T, Armbrust D, Rodbell KP, Gates SM. Characterization of Thin Dielectric Films as Copper Diffusion Barriers Using Triangular Voltage Sweep. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-565-189] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractAs technology progresses, the need for thinner Cu diffusion barrier caps is becoming more important, and it is advantageous if these barriers have low dielectric constants (κ). Towards this end, we characterized Cu penetration in several thin (35 nm to 70 nm) dielectrics, including silicon nitrides, silicon oxynitrides, an amorphous hydrogenated carbon film, and a methyl silsesquioxane layer. Metal Insulator Silicon (MIS) structures were used as the test vehicle. The barrier dielectrics were deposited on 100 nm thermal oxide which was grown on 2 Ω-cm, n-type Si wafers. After the deposition of 50 nm TEOS capping layers, both Al and Cu dots were evaporated on each wafer through a mask. Both Al and Cu dot samples were stressed at +2.7 MV/cm at 300°C for 10 minutes. For Cu dots, the applied stress pushed Cu ions into the dielectric stack. Stressing Al dots characterized the effects of the stress on the dielectric stacks and the quantity of Na ions in the films. Since C-V shifts are subject to stress-related instabilities in the interfaces as well as within the dielectrics themselves, triangular voltage sweep (TVS) was used after the applied stress to measure the concentration of Cu which reached the underlying thermal oxide film. The sensitivity of the TVS test with the structures used is about 5×109/cm2. Secondary ion mass spectroscopy (SIMS) analyses were performed on some of these samples to verify the electrical results.
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Welch DR, Cohen SA, Genoni TC, Glasser AH. Formation of field-reversed-configuration plasma with punctuated-betatron-orbit electrons. Phys Rev Lett 2010; 105:015002. [PMID: 20867454 DOI: 10.1103/physrevlett.105.015002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2010] [Indexed: 05/29/2023]
Abstract
We describe ab initio, self-consistent, 3D, fully electromagnetic numerical simulations of current drive and field-reversed-configuration plasma formation by odd-parity rotating magnetic fields (RMF{o}). Magnetic-separatrix formation and field reversal are attained from an initial mirror configuration. A population of punctuated-betatron-orbit electrons, generated by the RMF{o}, carries the majority of the field-normal azimuthal electrical current responsible for field reversal. Appreciable current and plasma pressure exist outside the magnetic separatrix whose shape is modulated by the RMF{o} phase. The predicted plasma density and electron energy distribution compare favorably with RMF{o} experiments.
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Affiliation(s)
- D R Welch
- Voss Scientific, Albuquerque, New Mexico 87108, USA
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Cohen SA, Berlinger B, Brunkhorst C, Brooks A, Ferraro N, Lundberg DP, Roach A, Glasser AH. Formation of collisionless high-beta plasmas by odd-parity rotating magnetic fields. Phys Rev Lett 2007; 98:145002. [PMID: 17501282 DOI: 10.1103/physrevlett.98.145002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2006] [Indexed: 05/15/2023]
Abstract
Odd-parity rotating magnetic fields (RMFo) applied to mirror-configuration plasmas have produced average electron energies exceeding 200 eV at line-averaged electron densities of approximately 10(12) cm-3. These plasmas, sustained for over 10(3)tauAlfven, have low Coulomb collisionality, vc* triple bond L/lambdaC approximately 10(-3), where lambdaC is the Coulomb scattering mean free path and L is the plasma's characteristic half length. Divertors allow reduction of the electron-neutral collision frequency to values where the RMFo coupling indicates full penetration of the RMFo to the major axis.
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Affiliation(s)
- S A Cohen
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey, USA
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Kim SY, Cohen SA, Epps J, Smedley J, Mendoza A, Khanna C, Jones B, Aziz N, Helman LJ. Reduction of murine osteosarcoma lung metastases using the dipeptidyl peptidase inhibitor talabostat. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.9009] [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] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
9009 Background: Dipeptidyl peptidases comprise a family of serine proteases that includes the genes dipeptidyl peptidase IV (DPP-IV) and fibroblast activation protein (FAP). FAP is expressed in stromal fibroblasts that surround sites of metastatic carcinomas, but not in the tumor cells themselves. Talabostat (valine-proline-boronic acid) is a potent and long-acting inhibitor of dipeptidyl peptidases. It has previously been shown to have anti-tumor activity in preclinical studies. We utilized this compound to determine whether inhibition of dipeptidyl peptidases leads to a decrease in lung metastases using a murine model of osteosarcoma metastasis. Methods: 1×106 K7M3-luciferase murine osteosarcoma cells were injected by tail vein into female Balb/C mice. Mice were then treated by gavage with talabostat (20 ug/dose) twice daily, talabostat once daily, or normal saline twice daily, 5 days on and 2 days off. Half of the mice were analyzed once a week using luminescent imaging. All animals were euthanized on day 24 and the number of lung metastases counted. Results: For the control mice, the average number of surface lung nodules was 75.6 (SD 45.4). Mice treated with talabostat had a ten-fold reduction in the number of nodules (twice daily - average 7.0, SD 6.1, p-value <0.01, once daily - average 3.4, SD 2.4, p-value <0.01). The number of resulting metastatic nodules correlated with luminescent intensity. Conclusions: Mice treated with the dipeptidyl peptidase inhibitor, talabostat, had a ten-fold decrease in the number of visible metastatic lung nodules. Experiments to elucidate the mechanism that links treatment with talabostat and inhibition of metastases are currently being performed. [Table: see text]
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Affiliation(s)
- S. Y. Kim
- National Institutes of Health, Bethesda, MD; Point Therapeutics Corp., Boston, MA
| | - S. A. Cohen
- National Institutes of Health, Bethesda, MD; Point Therapeutics Corp., Boston, MA
| | - J. Epps
- National Institutes of Health, Bethesda, MD; Point Therapeutics Corp., Boston, MA
| | - J. Smedley
- National Institutes of Health, Bethesda, MD; Point Therapeutics Corp., Boston, MA
| | - A. Mendoza
- National Institutes of Health, Bethesda, MD; Point Therapeutics Corp., Boston, MA
| | - C. Khanna
- National Institutes of Health, Bethesda, MD; Point Therapeutics Corp., Boston, MA
| | - B. Jones
- National Institutes of Health, Bethesda, MD; Point Therapeutics Corp., Boston, MA
| | - N. Aziz
- National Institutes of Health, Bethesda, MD; Point Therapeutics Corp., Boston, MA
| | - L. J. Helman
- National Institutes of Health, Bethesda, MD; Point Therapeutics Corp., Boston, MA
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20
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Landsman AS, Cohen SA, Glasser AH. Onset and saturation of ion heating by odd-parity rotating magnetic fields in a field-reversed configuration. Phys Rev Lett 2006; 96:015002. [PMID: 16486467 DOI: 10.1103/physrevlett.96.015002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2005] [Indexed: 05/06/2023]
Abstract
Heating of figure-8 orbit ions by odd-parity rotating magnetic fields (RMF(O)) applied to an elongated field-reversed configuration (FRC) is investigated. The largest energy gain occurs at resonances (s congruent to omega(R)/omega) of the RMF(O) frequency, omega(R), with the figure-8 orbital frequency, omega, and is proportional to s2 for s-even resonances and to s for s-odd resonances. The threshold for the transition from regular to stochastic orbits explains both the onset and saturation of heating. The FRC magnetic geometry lowers the threshold for heating below that in the tokamak by an order of magnitude.
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Affiliation(s)
- A S Landsman
- Naval Research Laboratory, Washington, Distrct of Columbia, USA.
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Abstract
STUDY DESIGN Prospective mortality study. OBJECTIVE To assess the relationship between comorbid medical conditions and other health-related factors to mortality in chronic spinal cord injury (SCI). SETTING Boston, MA, USA. METHODS Between 1994 and 2000, 361 males >/=1 year after injury completed a respiratory health questionnaire and underwent pulmonary function testing. Cause-specific mortality was assessed over a median of 55.6 months (range 0.33-74.4 months) through 12/31/2000 using the National Death Index. RESULTS At entry, mean (+/-SD) age was 50.6+/-15.0 years (range 23-87) and years since injury was 17.5+/-12.8 years (range 1.0-56.5). Mortality was elevated (observed/expected deaths=37/25.1; SMR=1.47; 95% CI=1.04-2.03) compared to US rates. Risk factors for death were diabetes (RR=2.62; 95% CI=1.19-5.77), heart disease (RR=3.66; 95% CI=1.77-7.78), reduced pulmonary function, and smoking. The most common underlying and contributing causes of death were diseases of the circulatory system (ICD-9 390-459) in 40%, and of the respiratory system in 24% (ICD-9 460-519). CONCLUSIONS These results suggest that much of the excess mortality in chronic SCI is related to potentially treatable factors. Recognition and treatment of cardiovascular disease, diabetes, and lung disease, together with smoking cessation may substantially reduce mortality in chronic SCI.
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Affiliation(s)
- E Garshick
- Pulmonary and Critical Care Medicine Section, VA Boston Healthcare System, Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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23
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Abstract
Benign metastasizing leiomyoma is a rare clinical entity that has been described in several previous reports. Although the exact pathophysiology of the disease is unknown, two predominant theories exist: (1) metastasis from an existing leiomyoma (commonly seen with uterine leiomyoma) or (2) multicentric leiomyomatous growths rather than actual metastases. We present an interesting case in which several elements of the patient's history complicated the differential diagnosis.
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Affiliation(s)
- W V Houck
- Section of General Thoracic Surgery, Division of Cardiothoracic Surgery, Department of Surgery, Medical College of Virginia Hospitals and Physicians of Virginia Commonwealth University Health System, Box 980068, Richmond, VA 23298-0068, USA
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Ramer MA, Lumerman H, Kopp W, Fisher KS, Cohen SA. Epithelioid hemangioendothelioma of the maxilla: case report and review of literature. Periodontal Clin Investig 2002; 23:31-5. [PMID: 11575111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Epithelioid Hemangioendothelioma (EH) is a rare, low-grade malignant vascular tumor, first defined as a soft tissue tumor by Enzinger and Weiss in 1982. The tumor was later reported in virtually all sites, including liver, lung, brain, and bone. The epithelioid neoplastic cells are of endothelial origin, staining positive for Factor VIII and CD-34. In our review of EH of bone medline literature, and including the present case report, a total of 73 cases were found. Forty-one (56%) patients had multifocal bone involvement and thirty-two (44%) patients had solitary EH of bone. Resection was the primary recommended treatment. Visceral involvement appears to affect prognosis and survival adversely. We report a case of EH of the maxilla, which occurred in a 32-year-old male.
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Affiliation(s)
- M A Ramer
- Mount Sinai Medical Center, New York, USA
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Liu HJ, Strong RE, Krull IS, Cohen SA. Homogeneous preparation of fluorescent-derivatized insulin and its application to competitive chromatographic immunoassays. Anal Biochem 2001; 298:103-11. [PMID: 11673901 DOI: 10.1006/abio.2001.5361] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [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: 11/22/2022]
Abstract
A homogeneously labeled insulin sample was prepared using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) as the fluorescent-labeling reagent, and this was successfully applied to a chromatographic immunoassay. This labeled insulin was prepared by tagging all the three amino groups with AQC. Both CE and chromatographic immunoassay experiments indicated that the prepared insulin still kept its immunoaffinity to its antibody. It was observed that appropriate concentrations of acetonitrile (ACN) were efficient in lowering the quenching of the fluorescent signal of tagged insulin, in keeping the dilute, tagged insulin in solution, and in improving its peak shape during a chromatographic immunoassay. The tagged insulin was found to be 20-400 times more sensitive than native insulin detected under ultraviolet detection conditions. A competitive chromatographic immunoassay system was set up and calibrated. The system was used for analyses of an insulin-spiked urine sample, with a 96% recovery obtained.
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Affiliation(s)
- H J Liu
- Department of Chemistry, Northeastern University, 102 Hurtig Building, 360 Huntington Avenue, Boston, Massachusetts 02115, USA
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26
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Abstract
A method of homogeneously derivatizing large proteins for highly sensitive analysis is described. Homogeneity of the derivative was realized by tagging all the free amino groups of proteins. With this method, alpha-chymotrypsinogen A, ovalbumin and bovine serum albumin were derivatized with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC). Prior to the derivatization, all the proteins were reduced and alkylated. After reacting the resulting unfolded proteins with excessive amounts of AQC, the samples were analyzed with matrix assisted laser desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS) to determine the derivatization degree. The results indicated that all three proteins had been, or had almost been, fully derivatized. HPLC and CE were used for characterizing these protein derivatives. Under the optimized fluorescence detection conditions, the detectability of the tagged proteins was 2400-6200 times better than that detected at UV 280 nm, 170-300 times better than detected at UV 214 nm, and 150-420 times better than measured with their native fluorescence.
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Affiliation(s)
- H Liu
- Department of Chemistry, Northeastern University, Boston, MA 02115, USA
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27
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Abstract
A highly sensitive peptide mapping method using derivatization and fluorescence detection is described. Bovine cytochrome c was digested using a buffer compatible with the derivatization that followed. The derivatization was performed with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate. The peptide mapping of the tagged digest was conducted with both HPLC and capillary LC (CLC) systems. A capillary LC-electrospray ionization mass spectrometer (MS) was set up for measuring the molecular weights of the tagged peptides. Optimization was made of the conditions used for digestion, derivatization, and mapping. MS measurements of the tagged peptides suggested that there was only one derivatization product produced from all peptides (except one) and that all the identified peptides were fully tagged. Peptide mapping of the tagged digest reviews a larger number of peptides, covering almost the entire sequence. Peptide mapping of a 20 fmol amount of tagged digest was readily performed with the CLC system. By using derivatization and fluorescence detection, the sensitivity of peptide mapping could be improved 2000 times compared to that observed with uv detection of untagged peptides.
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Affiliation(s)
- H Liu
- Department of Chemistry, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, USA
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28
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Cohen SA, Paeglow RJ. Scurvy: an unusual cause of anemia. J Am Board Fam Pract 2001; 14:314-6. [PMID: 11458974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Affiliation(s)
- S A Cohen
- Department of Family and Community Medicine, Albany Medical Center, NY, USA
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Abstract
BACKGROUND Compartment syndrome is a condition in which increased tissue pressure within a limited tissue space compromises the circulation and function of the contents of the space. CASE A 43-year-old black woman, para 3, had repair of a recurrent vesicovaginal fistula. She was placed in a low lithotomy position with thigh length sequential compression sleeves. The procedure lasted more than 5 hours. On postoperative day 1, she complained of pain in her right leg and foot. Compartment syndrome was diagnosed and emergency fasciotomy was done. CONCLUSION Gynecologists should be aware of the possibility of compartment syndrome during prolonged procedures with patients in the lithotomy position. Concomitant intermittent compression sleeves might further increase the risk. Early diagnosis and treatment of compression syndrome are essential to minimize long-term neurovascular morbidity.
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Affiliation(s)
- S A Cohen
- Department of Obstetrics and Gynecology, Virginia Commonwealth University, Medical College of Virginia Hospitals, PO Box 980034, Richmond, VA 23298-0034, USA.
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Abstract
Historically, endoscopic retrograde cholangeopancreatography (ERCP) has played a unique role as a diagnostic and therapeutic modality for diseases of the pancreas. Despite the advent of new imaging techniques, ERCP continues to play a central role in the evaluation and treatment of pancreatitis of various causes. Endoscopic cholangiography and stenting remain mainstays in the palliation of inoperable obstructive jaundice in patients with cancer of the pancreas.
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Affiliation(s)
- S A Cohen
- Columbia University College of Physicians and Surgeons, and Division of Gastroenterology, St Lukes-Roosevelt Hospital Center, New York, New York, USA
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31
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Abstract
Pancreas divisum is a common congenital variation that can be associated with pancreatic disease. Symptomatic patients with divisum must be classified according to clinical presentation and morphologic findings. Response to endoscopic therapy is best in patients with ARP, of whom 75% benefit. Results in patients with chronic pancreatitis and pain but without objective pancreatitis are mixed, and patients should be carefully selected.
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Affiliation(s)
- S A Cohen
- Columbia University College of Physicians and Surgeons, and Division of Gastroenterology, St. Luke's-Roosevelt Hospital Center, New York, New York, USA
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32
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Affiliation(s)
- S A Cohen
- Waters Corporation, Milford, MA, USA
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33
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Ribaux P, Bleicher F, Couble ML, Amsellem J, Cohen SA, Berthier C, Blaineau S. Voltage-gated sodium channel (SkM1) content in dystrophin-deficient muscle. Pflugers Arch 2001; 441:746-55. [PMID: 11316257 DOI: 10.1007/s004240000483] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The membrane cytoskeleton is increasingly considered as both an anchor and a functional modulator for ion channels. The cytoskeletal disruptions that occur in the absence of dystrophin led us to investigate the voltage-gated sodium channel (SkM1) content in the extensor digitorum longus (EDL) muscle of the dystrophin-deficient mdx mouse. Levels of SkM1 mRNA were determined by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR). A C-terminal portion of the mouse-specific SkM1 alpha-subunit cDNA (mScn4a) was identified first. SkM1 mRNA levels were as abundant in mdx as in normal muscle, thus suggesting that the transcriptional rate of SkM1 remains unchanged in mdx muscle. However, SkMI density in the extrajunctional sarcolemma was shown to be significantly reduced in mdx muscle, using confocal immunofluorescence image analysis. This decrease was found to be associated with a reduction in the number of SkM1-rich fast-twitch IIb fibres in mdx muscle. In addition, lowered SkM1 sarcolemmal labelling was found in all mdx fibres regardless of their metabolic type. These results suggest the existence of a perturbation of SkM1 anchorage to the plasma membrane. Such an alteration is likely to be related to the 50% decrease in mdx muscle of the dystrophin-associated syntrophins, which are presumed to be involved in SkM1 anchorage. However, the moderate reduction in SkM1 density (-12.7%) observed in mdx muscle argues in favour of a non-exclusive role of syntrophins in SkM1 anchorage and suggests that other membrane-associated proteins are probably also involved.
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MESH Headings
- Animals
- Base Sequence
- Consensus Sequence
- Dystrophin/genetics
- Gene Expression
- Immunohistochemistry
- Ion Channel Gating/physiology
- Mice
- Mice, Inbred C57BL
- Mice, Inbred mdx
- Molecular Sequence Data
- Muscle Fibers, Fast-Twitch/chemistry
- Muscle Fibers, Fast-Twitch/metabolism
- Muscle Fibers, Fast-Twitch/pathology
- Muscle Fibers, Slow-Twitch/chemistry
- Muscle Fibers, Slow-Twitch/metabolism
- Muscle Fibers, Slow-Twitch/pathology
- Muscle, Skeletal/chemistry
- Muscle, Skeletal/pathology
- Muscle, Skeletal/physiology
- Muscular Dystrophy, Animal/genetics
- Muscular Dystrophy, Animal/metabolism
- Muscular Dystrophy, Animal/pathology
- RNA, Messenger/analysis
- Reverse Transcriptase Polymerase Chain Reaction
- Sarcolemma/chemistry
- Sarcolemma/metabolism
- Sodium Channels/analysis
- Sodium Channels/genetics
- Sodium Channels/metabolism
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Affiliation(s)
- P Ribaux
- Université Claude Bernard Lyon 1, Laboratoire de Physiologie des Eléments Excitables, Villeurbanne, France
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Cohen SA, Glasser AH. Ion heating in the field-reversed configuration by rotating magnetic fields near the ion-cyclotron resonance. Phys Rev Lett 2000; 85:5114-5117. [PMID: 11102199 DOI: 10.1103/physrevlett.85.5114] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2000] [Indexed: 05/23/2023]
Abstract
The trajectories of ions confined in a field-reversed configuration (FRC) equilibrium magnetic geometry and heated with a small-amplitude, odd-parity rotating magnetic field (RMF) have been studied with a Hamiltonian computer code. When the RMF frequency is in the ion-cyclotron range, explosive heating occurs. Higher-energy ions are found to have betatron-type orbits, preferentially localized near the FRC's midplane. These results are relevant to a compact magnetic-fusion-reactor design.
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Affiliation(s)
- SA Cohen
- Princeton University, Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
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35
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Zhang H, Kolibal S, Vanderkooi JM, Cohen SA, Kallen RG. A carboxy-terminal alpha-helical segment in the rat skeletal muscle voltage-dependent Na+ channel is responsible for its interaction with the amino-terminus. Biochim Biophys Acta 2000; 1467:406-18. [PMID: 11030598 DOI: 10.1016/s0005-2736(00)00238-8] [Citation(s) in RCA: 10] [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: 11/30/2022]
Abstract
Cytoplasmic segments of the adult rat skeletal muscle sodium channel alpha-subunit (rSkM1) comprise a major portion (approximately 40%) of the total protein and are involved in channel functions both general, such as inactivation, and isoform-specific, for example, protein kinase A modulation. Far ultraviolet circular dichroism measurements of synthetic peptides and overexpressed fusion proteins containing individual channel cytoplasmic segments suggest that cytoplasmic domains of rSkM1 contain ordered secondary structures even in the absence of adjoining transmembrane segments. Intrinsic fluorescence experiments with a nested set of carboxy-terminal deletion proteins confirm a specific interaction between the channel's amino- and carboxy-termini and identify residues 1716-1737 in the carboxy-terminus as the region that binds to the amino-terminus. Circular dichroism measurements suggest that this same region is organized as an alpha-helix and that electrostatic forces may contribute to this association. The interaction of the amino- and carboxy-termini is not accompanied by secondary structure changes detectable by circular dichroism spectroscopy, but a decrease in intrinsic fluorescence indicates that this association is accompanied by a change in the environment of Trp1617.
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Affiliation(s)
- H Zhang
- Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, Philadelphia 19104-6059, USA
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Siegel JH, Cohen SA, Kasmin FE. Experience and volume: the ingredients for successful therapeutic endoscopic outcomes, especially ERCP and postgastrectomy patients. Am J Gastroenterol 2000; 95:2133-4. [PMID: 10950082 DOI: 10.1111/j.1572-0241.2000.02212.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Wang Z, Cohen SA, Ruzic DN, Goeckner MJ. Nitrogen atom energy distributions in a hollow-cathode planar sputtering magnetron. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 2000; 61:1904-1911. [PMID: 11046476 DOI: 10.1103/physreve.61.1904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/1999] [Revised: 09/30/1999] [Indexed: 05/23/2023]
Abstract
Energy distributions of nitrogen atoms (N) in a hollow-cathode planar sputtering magnetron were obtained by use of optical emission spectroscopy. A characteristic line, N I 8216.3 A, well separated from molecular nitrogen emission bands, was identified. Jansson's nonlinear spectral deconvolution method, refined by minimization of chi(2)(w), was used to obtain the optimal deconvolved spectra. These showed nitrogen atom energies from 1 eV to beyond 500 eV. Based on comparisons with VFTRIM computer code results, it is proposed that the energetic N's are generated from N+2 ions after these ions are accelerated through the sheath and dissociatively reflect from the cathode.
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Affiliation(s)
- Z Wang
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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38
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Cohen SA, Trikha M, Mascelli MA. Potential future clinical applications for the GPIIb/IIIa antagonist, abciximab in thrombosis, vascular and oncological indications. Pathol Oncol Res 2000; 6:163-74. [PMID: 11033455 DOI: 10.1007/bf03032368] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [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: 10/21/2022]
Abstract
Abciximab (ReoPro) is a mouse-human chimeric monoclonal antibody Fab fragment of the parent murine monoclonal antibody 7E3, and was the first of these agents approved for use as adjunct therapy for the prevention of cardiac ischemic complications in patients undergoing percutaneous coronary intervention (PCI). Abciximab binds with high avidity to both the non-activated and activated form of the GPIIb/IIIa receptor of platelets, the major adhesion receptor involved in aggregation. Additional cardiovascular indications for abciximab are unstable angina, carotid stenting, ischemic stroke and peripheral vascular diseases. Abciximab also interacts with two other integrin receptors; the a av b b3 receptor, which is present in low numbers on platelets but in high density on activated endothelial and smooth muscle cells, and a aMb b2 integrin which is present on activated leukocytes. Cell types that express integrins GPIIb/IIIa and a av b b3 such as platelets, endothelial and tumor cells have been implicated in angiogenesis, tumor growth and metastasis. Since abciximab interacts with high avidity to integrins GPIIb/IIIa and a av b b3, it is reasonable to assume that it may possess anti-angiogenic properties in angiogenesis-related diseases, as well as anti-metastastatic properties in case of disseminating tumors expressing the target integrin receptors.
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Affiliation(s)
- S A Cohen
- Cenrocor Inc. 200 Great Valley Parkway, Malvern, PA 19355, USA
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Hunziker P, Andersen TT, Bao Y, Cohen SA, Denslow ND, Hulmes JD, Mahrenholz AM, Mann K, Schegg KM, West KA, Crabb JW. Identification of proteins electroblotted to polyvinylidene difluoride membrane by combined amino acid analysis and bioinformatics: An ABRF multicenter study. J Biomol Tech 1999; 10:129-136. [PMID: 19499016 PMCID: PMC2291601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The ABRF amino acid analysis study evaluated the general utility of amino acid analysis (AAA) for identification of proteins after denaturing gel electrophoresis and electroblotting to polyvinylidene difluoride (PVDF) membrane.Thirty-eight participating laboratories analyzed a known control (ovalbumin, 5 microg applied to the gel) and either lysozyme or bovine serum albumin as unknown samples (1-, 5-, and 10-microg amounts applied to the gel). Analyses of the unknowns yielded average compositional errors of approximately 30%, 19%, and 18%, respectively, from the low, intermediate, and higher sample amounts; the ovalbumin control exhibited an approximately 17% average error. Compositional data were submitted to the ExPASy and PROPSEARCH Internet sites for protein identification.Without search parameter adjustments or restrictions, both computer programs provided identification of about 20%, 66%, and 74% of the data from the 1-, 5-, and 10-microg gel samples, respectively. Deleting problematic data (Gly, Met, and Pro) did not always facilitate protein identification. Incorporating control results into the ExPASy search increased identifications 2% to 10%, and restricting search parameters by species, isoelectric pH, and molecular weight increased identifications by more than 80%. Average amounts analyzed for correct identifications were approximately 0.4 microg, 1.8 microg, and 2.9 microg for the 1-, 5-, and 10-microg gel samples, respectively.The results support the efficacy of AAA in the low microgram and nanogram range for the identification of PVDF-immobilized proteins from two-dimensional gels.
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Affiliation(s)
- P Hunziker
- Biochemisches Institut, University of Zurich, Zurich, Switzerland.
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Kuryshev YA, Brittenham GM, Fujioka H, Kannan P, Shieh CC, Cohen SA, Brown AM. Decreased sodium and increased transient outward potassium currents in iron-loaded cardiac myocytes. Implications for the arrhythmogenesis of human siderotic heart disease. Circulation 1999; 100:675-83. [PMID: 10441107 DOI: 10.1161/01.cir.100.6.675] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.0] [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] [Indexed: 12/21/2022]
Abstract
BACKGROUND Patients with chronic iron overload may develop a cardiomyopathy manifested by ventricular arrhythmias and heart failure. We hypothesized that iron-loaded cardiomyocytes may have abnormal excitability. METHODS AND RESULTS We examined a new model of human iron overload, the Mongolian gerbil given repeated injections of iron dextran. In ventricular myocytes, we measured iron concentration and distribution, action potential, sodium and potassium currents, and sodium channel protein. We showed for the first time that (1) the iron content of gerbil ventricular cardiomyocytes was increased to amounts similar to those of patients with iron-induced cardiomyopathy; (2) the overshoot and duration of the cardiac action potential decreased; (3) sodium current was reduced, steady-state inactivation was enhanced, and single-channel currents were unchanged; and (4) transient outward potassium current was increased, but inwardly rectifying potassium current was unchanged. Neonatal rat cardiomyocytes incubated with iron for 1 to 3 days showed similar changes, and levels of cardiac sodium channel proteins were unchanged. CONCLUSIONS Abnormal excitability and heterogeneous cardiac iron deposition may cause the arrhythmogenesis of human siderotic heart disease.
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Affiliation(s)
- Y A Kuryshev
- Rammelkamp Center for Education and Research, MetroHealth Campus, Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, Ohio, USA
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Cohen SA. Robbing family planning to fund child survival: undermining women and children. Guttmacher Rep Public Policy 1999; 2:3-5. [PMID: 12346542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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Abstract
BACKGROUND Although the liver is a potent tumor cell killing organ it is frequently the site of lethal metastases often signifying the endstage for patients with colorectal cancers. Enhancing hepatic-associated immunity remains elusive until the interactions among hepatic nonparenchymal cells (NPC) are deciphered. We sought to modulate the cellular components of the hepatic immune system of mice with anti-NK and anti-T-cell-neutralizing antibodies in order to determine the cell type most efficacious in preventing liver metastasis. MATERIALS AND METHODS Liver-derived murine colon adenocarcinoma (LD-MCA-38) cells were injected into the ileocolic vein (ICV) of immunocompetent and immunodeficient C57BL/6 mice. Mice were pretreated 1 day prior to tumor cell injection with one of three antibodies: anti-AsGM1, Anti-NK1.1, or Anti-Thy1.2. On Day 21 laparotomy was performed to determine the extent of hepatic tumor foci. The number of hepatic tumor foci was recorded and compared by the Wilcoxon rank sum test. RESULTS Mice pretreated with anti-AsGM1 or Anti-NK1.1 developed a massive increase in the number of hepatic tumor foci and decreased survival compared to the control treated mice. Pretreatment with anti-Thy1.2 antibody resulted in a significant decrease in the number of hepatic tumor foci. LD-MCA-38 tumor cells were unable to colonize the liver of C57BL/6 athymic nude mice; however, anti-AsGM1 antibody abolished this antimetastatic effect. There was no difference in the extent of hepatic metastasis and survival between immunodeficient C57BL/6 bg/bg and their conventional littermates bg/+. CONCLUSION AsGM1+ NK cells exhibit a significant antitumor response in the absence of T-cells. The concept of stimulating NK cell activity and suppressing T-cell function may enhance liver-associated immunity and serve as a deterrent for blood-borne tumor cells metastasizing to the liver.
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MESH Headings
- Adenocarcinoma/prevention & control
- Adenocarcinoma/secondary
- Animals
- Antibodies/pharmacology
- Antibodies, Monoclonal/pharmacology
- Antigens/immunology
- Antigens, Ly
- Antigens, Surface
- Colonic Neoplasms/pathology
- G(M1) Ganglioside/immunology
- G(M1) Ganglioside/metabolism
- Immunocompetence/physiology
- Killer Cells, Natural/metabolism
- Killer Cells, Natural/physiology
- Lectins, C-Type
- Liver Neoplasms/prevention & control
- Liver Neoplasms/secondary
- Lymphocyte Count/drug effects
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL/genetics
- Mice, Nude/immunology
- NK Cell Lectin-Like Receptor Subfamily B
- Neoplasm Invasiveness/prevention & control
- Neoplasm Transplantation
- Proteins/immunology
- T-Lymphocytes/pathology
- Thy-1 Antigens/immunology
- Tumor Cells, Cultured
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Affiliation(s)
- C M Volpe
- Department of Surgery, Buffalo VA Medical Center and CGF Health Systems, Buffalo, New York, 14203, USA.
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Cohen SA. Objections, confusion among pharmacists threaten access to emergency contraception. Guttmacher Rep Public Policy 1999; 2:1-3. [PMID: 12295186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
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Cohen SA. "Cairo-Plus-Five" review is finding political will strong -- but funds lacking. Guttmacher Rep Public Policy 1999; 2:5-7. [PMID: 12349123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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Cohen SA, Navathe AS. Feeding the developmentally delayed child. J Med Assoc Ga 1999; 88:71-6. [PMID: 10341496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Cohen SA. The United States and the United Nations Population Fund: a rocky relationship. Guttmacher Rep Public Policy 1999; 2:1-2, 14. [PMID: 12321966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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Liu H, Sañuda-Peña MC, Harvey-White JD, Kalra S, Cohen SA. Determination of submicromolar concentrations of neurotransmitter amino acids by fluorescence detection using a modification of the 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate method for amino acid analysis. J Chromatogr A 1998; 828:383-95. [PMID: 9916319 DOI: 10.1016/s0021-9673(98)00836-x] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A sensitive method for quantitatively determining submicromolar levels of neurotransmitter amino acids (e.g. Asp, Glu and gamma-aminobutyric acid) in microdialysates from brain and cerebrospinal fluids is reported. 6-Aminoquinolyl-N-hydroxy-succinimidyl carbamate (AQC) was employed as the derivatization reagent, followed by HPLC separation and fluorescence detection of the derivatives. The derivatization was conducted simply by mixing the AQC directly with the microdialysis samples. The reaction was complete within seconds after mixing at room temperature. Separation development optimizing the gradient profile, eluent pH and column temperature resulted in an excellent separation of the required amino acids in less than 30 min. Other resolved amino acids in the same profile include Gly, taurine, and Pro. Recoveries for the amino acids of interest spiked into high salt containing perfusion buffers were greater than 97%. The sensitivity of the method was increased by employing a 16-microliter flow cell in the detector and analyzing 20-microliter aliquots of the derivatization mixtures. With the optimized conditions, the detection limits were 3-7 nM (fmol/microliter). Typical reproducibility (%R.S.D.) for quantitation of these amino acids at submicromolar levels was approximately 2%. Excellent linearity (r2 > 0.999) was achieved over the range 0.2-20 microM. The low detection limits permitted the analysis of a number of different microdialysate samples including those from cerebrospinal fluid, as well as substantia nigra and hypothalamus from brain samples, even at basal levels where gamma-aminobutyric acid concentration may be < 50 nM. The excellent sensitivity made it easy to distinguish basal from stimulated levels of neurotransmitter amino acids, even from sample sizes as small as 10 microliters.
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Affiliation(s)
- H Liu
- Waters Corporation, Milford, MA 01757, USA
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Cohen SA. The reproductive health needs of refugees: emerging consensus attracts predictable controversy. Guttmacher Rep Public Policy 1998; 1:10-2. [PMID: 12348740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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Mehta N, Hordines J, Sykes D, Doerr RJ, Cohen SA. Low density lipoproteins and Lovastatin modulate the organ-specific transendothelial migration of primary and metastatic human colon adenocarcinoma cell lines in vitro. Clin Exp Metastasis 1998; 16:587-94. [PMID: 9932605 DOI: 10.1023/a:1006548902592] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [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
Tumor cell arrest and tumor migration are two of the critical steps in the metastatic cascade. We hypothesized that these steps may be facilitated by the low density lipoprotein (LDL)-induced activation of microvessel endothelial cells (MVEC). The purpose of our study was to investigate the biological effects of an LDL-enriched milieu and the effects of the anticholesterol drug Lovastatin on metastatic behavior. The SW480 and SW620 are primary and metastatic human colonic adenocarcinoma cell lines derived from the same patient. We investigated the effect of LDL on adhesion and migration of the two tumor cell lines across human brain, lung, liver and dermal endothelial monolayers. Adhesion and migration assays were done before and after pretreatment of the MVEC or tumor cells with LDL (100 microg/ml) for 24 h. Although metastatic SW620 cells were more adherent to MVEC compared with primary SW480 cells, LDL pretreatment of SW480 and SW620 cells did not affect tumor cell adhesion to MVEC. In contrast, tumor cell migration was significantly increased across endothelial monolayers when MVEC were pretreated with LDL. Transendothelial cell migration was not significantly affected by pretreatment of the tumor cells with LDL. Lovastatin is an inhibitor of HMG-CoA reductase, the rate-limiting enzyme in cholesterol biosynthesis. It has been shown to have anti-tumor activity in vitro. We investigated the effect of Lovastatin on tumor cell kinetics and tumor cell migration across MVEC. Growth curves and migration assays were done before and after pretreatment of the tumor cells with Lovastatin (30 microg/ml). Migration assays were also done after treatment of unstimulated or LDL-stimulated MVEC (100 microg/ml) for 24 h with Lovastatin. Lovastatin inhibited the in vitro growth of the metastatic SW620 cell line to a greater extent than the invasive SW480E cell line. On the other hand, pretreatment of tumor cells with Lovastatin (30 microg/ml) did not suppress transendothelial tumor cell migration of tumor cells. Finally, Lovastatin given to mice effectively suppressed the number of MCA-26 tumor colonies in the liver of Balb/c mice compared with untreated mice.
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Affiliation(s)
- N Mehta
- VA Medical Center, Department of Surgery, School of Medicine, State University of New York at Buffalo, 14215, USA
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Kolibal SS, Brady C, Cohen SA. Definition of epitopes for monoclonal antibodies developed against purified sodium channel protein: implications for channel structure. J Membr Biol 1998; 165:91-9. [PMID: 9705985 DOI: 10.1007/s002329900423] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
To test sodium channel structural models, we defined the epitopes for nineteen independently cloned monoclonal antibodies previously generated against purified, detergent-solubilized, adult rat skeletal muscle sodium channel protein using channel proteolysis, synthetic peptides, and fusion proteins. All identified epitopes were continuous and unique to the skeletal muscle subtype alpha-subunit. Of the nineteen independent clones, seventeen had epitopes located either in the origin of the amino-terminus or in the interdomain 2-3 region while only two antibodies had epitopes located in the mid-portion of the interdomain 1-2 region. No immunogenic regions were identified on the alpha-subunit's extracellular regions, interdomain 3-4 segment, or carboxyl-terminus or on channel beta-subunits. While immune tolerance may explain the lack of immunogenicity of extracellular regions, the lack of immunogenicity of most of the channel's cytoplasmic mass may be due to segment inaccessibility from organization of these regions as globular domains, to insertion of parts of these regions into the membrane phase, or to interaction with other protein elements. The definition of monoclonal antibody epitopes allows us to reinterpret previously reported monoclonal antibody competition studies, providing independent support for our model of sodium channel cytoplasmic domain structure. In addition, these data suggest additional testable hypotheses concerning the interactions of the sodium channel amino- and carboxyl-termini with each other as well as with other protein elements.
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Affiliation(s)
- S S Kolibal
- Department of Medicine, MCP Hahnemann School of Medicine, Allegheny University of the Health Sciences, Philadelphia, PA 19129, USA
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