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Abstracts of the 33rd International Austrian Winter Symposium : Zell am See, Austria. 24-27 January 2018. EJNMMI Res 2018; 8:5. [PMID: 29362999 PMCID: PMC5780335 DOI: 10.1186/s13550-017-0354-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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The Addition of Chemotherapy to Radiation Therapy Improves Survival in Elderly Patients with Stage III Non-Small Cell Lung Cancer. J Thorac Oncol 2018; 13:426-435. [PMID: 29326090 DOI: 10.1016/j.jtho.2017.11.135] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 11/16/2017] [Accepted: 11/20/2017] [Indexed: 12/25/2022]
Abstract
INTRODUCTION Elderly patients account for the majority of lung cancer diagnoses but are poorly represented in clinical trials. We evaluated the overall survival (OS) of elderly patients with stage III NSCLC treated with definitive radiation compared with that of patients treated with definitive chemoradiation. METHODS We conducted a comparative effectiveness study of radiation therapy versus chemoradiation in elderly (≥70 years old) patients with stage III NSCLC not treated surgically diagnosed from 2003 to 2014; the patients were identified by using the National Cancer Database. Two cohorts were evaluated: patients (n = 5023) treated with definitive radiation (≥59.4 Gy) and patients (n = 18,206) treated with definitive chemoradiation. Chemoradiation was further defined as concurrent (radiation and chemotherapy started within 30 days of each other) or sequential (radiation started >30 days after chemotherapy). We compared OS between the treatment groups by using the Kaplan-Meier method and Cox proportional hazards regression before and after propensity score matching (PSM). RESULTS Treatment with chemoradiation was associated with improved OS versus that with radiation both before PSM (hazard ratio [HR] = 0.66, 95% confidence interval [CI]: 0.64-0.68, p < 0.001) and after PSM (HR = 0.67, 95% CI: 0.64-0.70, p < 0.001). Relative to concurrent chemoradiation, sequential chemoradiation was associated with a 9% reduction in the risk for death (HR = 0.91, 95% CI: 0.85-0.96, p = 0.002). CONCLUSIONS We found that definitive chemoradiation resulted in a survival advantage compared with definitive radiation in elderly patients. Sequential chemotherapy and radiation was superior to concurrent chemoradiation. Although prospective trials are needed, this analysis suggests that chemoradiation should be strongly considered for elderly patients and the optimal sequencing of chemotherapy and radiation remains an unanswered question for this patient population.
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Sinonasal adenoid cystic carcinoma: Treatment outcomes and association with human papillomavirus. Head Neck 2017; 39:1405-1411. [PMID: 28370900 DOI: 10.1002/hed.24778] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 11/17/2016] [Accepted: 02/09/2017] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND The purpose of this study was to review long-term outcomes of sinonasal adenoid cystic carcinoma (ACC) and to clarify its association with human papillomavirus (HPV). METHODS The medical records of 23 patients with sinonasal ACC treated with primary surgical resection between 1998 and 2013 were reviewed. Tissue specimens were available for 17 patients. The p16 testing was performed using immunohistochemistry (IHC), and HPV infection was determined using quantitative polymerase chain reaction (PCR) with primers targeting the E6/E7 region. RESULTS Two of the 17 samples showed strong and diffuse p16 staining, whereas the remaining 15 cases showed p16-positivity isolated to the luminal cells. Only one of the p16-positive cases was positive for HPV. The 5-year local failure, disease-free survival (DFS), and overall survival (OS) were 51%, 52%, and 62%, respectively. CONCLUSION Local failures are common with advanced sinonasal ACC, and the association of HPV with true sinonasal ACC is low.
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Making Sense of the Brutality of the Holocaust: Critical Themes and New Perspectives. THE JOURNAL OF PSYCHOLOGY 2016; 151:88-106. [DOI: 10.1080/00223980.2016.1217191] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Patterns of major wound complications following multidisciplinary therapy for lower extremity soft tissue sarcoma. J Surg Oncol 2016; 114:385-91. [PMID: 27238092 DOI: 10.1002/jso.24313] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 05/16/2016] [Indexed: 11/06/2022]
Abstract
BACKGROUND AND OBJECTIVES The purpose of this study was to determine the pattern and timing of major wound complications (MWCs) in patients at our institution who received multimodality treatment for lower extremity soft tissue sarcoma (LE-STS) and to evaluate the impact of MWCs on tumor control and patient outcomes. METHODS The medical records of 102 LE-STS patients treated with limb-sparing surgery and radiation therapy were reviewed. MWCs were defined as secondary operations with anesthesia, seroma/hematoma aspiration, admission for IV antibiotics, or persistent deep packing. RESULTS MWCs occurred in 22% of patients, with 45% of events occurring >120 days after resection. On multivariate analysis, preoperative external beam radiation therapy (EBRT) (OR 4.29, 95% CI 1.06-17.40, P = 0.042) and skin graft placement (OR 6.39, 95% CI 1.37-29.84, P = 0.018) were found to be independent predictors of MWCs. MWC occurrence did not predict for chronic toxicity and did not impact tumor control or survival. CONCLUSIONS A considerable proportion of MWCs occur >120 days from surgical resection with preoperative EBRT and skin graft placement independent predictors for MWCs. While an additional source of morbidity, MWC occurrence did not impact tumor control, nor did it predict for chronic toxicity. J. Surg. Oncol. 2016;114:385-391. © 2016 Wiley Periodicals, Inc.
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Abstract
This article argues for the development of an interdisciplinary psychology of loss that is focused on people's pervading commonsense experience and recognition of loss in their own and others' lives. This field may be defined as broader than related fields such as traumatology, thanatology, and stress and coping. The psychology of loss focuses on the perception of major loss deriving from events such as death and divorce, but also on the perception of major loss in connection with such diverse phenomena as loss of employment, loss of bodily functioning, and being the target of violence or prejudice, including genocide. An important research topic for this field concerns people's stories of how major losses are interrelated in their lives. It is argued that perceived loss is a critical phenomenal state that must be dealt with in adaptation to most significant stressors.
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Mini-laparotomy with Adjunctive Care versus Laparoscopy for Placement of Gastric Electrical Stimulation. Am Surg 2016. [DOI: 10.1177/000313481608200419] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We compared outcomes for two gastric electrical stimulation placement strategies, mini-laparotomy with adjunctive care (MLAC) versus laparoscopy without adjunctive care (LAPA). For electrode placement, the peritoneal cavity was accessed with either a single 2.5 to 3.0 cm midline incision (MLAC) or three trocar incisions (LAPA). For both groups, generator was placed subcutaneously over the anterior rectus sheath. For MLAC, adjunctive pain control measures were used for placement of both electrode and generator (transversus abdominus plane block). For LAPA, those that could not be completed by laparoscopy were converted to traditional open approach and kept in the analysis. MLAC (n = 128) resulted in shorter operative times than LAPA (n = 37) (median operative time: 87.5 vs 137.0 minutes, P ≤ 0.01). Hospital length of stay was also shorter for MLAC than for LAPA (median: 2.0 vs 3.0 days, P ≤ 0.01) without any increase in readmission rates to the hospital within 30 days of discharge (11.0 vs 16.2%, P = 0.39). After equalizing learning curves, these differences were even greater (median operative time: 84.5 vs 137.0 minutes, P < 0.01; median length of stay: 1.0 vs 3.0 days; P < 0.01) without increasing 30-day read-mission rates (9.1 vs 16.2%, P = 0.25). For implantation of gastric electrical stimulators, mini-laparotomy can result in improved outcomes when coupled with adjunctive pain control measures.
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Review of Journalism and Memorialization in The Age of Social Media, by Peter Joseph Gloviczki. JOURNAL OF LOSS & TRAUMA 2016. [DOI: 10.1080/15325024.2016.1157414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Content Analysis of Select YouTube Postings: Comparisons of Reactions to the Sandy Hook and Aurora Shootings and Hurricane Sandy. CYBERPSYCHOLOGY, BEHAVIOR AND SOCIAL NETWORKING 2015; 18:635-40. [PMID: 26379103 DOI: 10.1089/cyber.2015.0045] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This study details an innovative and methodical content analysis of 2,207 YouTube comments from four different YouTube videos (e.g., breaking news or memorials) related to the 2012 Sandy Hook Elementary School and Aurora theater mass shootings and the catastrophic Hurricane Sandy. As expected, YouTube comments associated with the Sandy Hook shootings (particularly those from a memorial video) were especially likely to feature compassion and grief with lessened hostility. This study highlights differing online contexts by which individuals show grief and related emotions following man-made and natural calamities and how-even in an online environment-powerful situational contexts greatly guide behavior.
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The role of modern radiation therapy in the management of extremity sarcomas. J Surg Oncol 2014; 111:599-603. [PMID: 25366825 DOI: 10.1002/jso.23823] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Accepted: 09/24/2014] [Indexed: 11/11/2022]
Abstract
For nearly half a decade, surgery and radiation therapy have been used in combination to achieve the goal of limb preservation in extremity soft tissue sarcoma, with success rates in excess of 90%. Common decision points in therapeutic radiation delivery for sarcoma are discussed, including preoperative versus postoperative irradiation, the postoperative boost, and when irradiation might be unnecessary. We describe specialized techniques, such as brachytherapy and intraoperative irradiation. The data driving current practice is summarized.
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Evaluations of hypothetical bereavement and grief: the influence of loss recency, loss type and gender. INTERNATIONAL JOURNAL OF PSYCHOLOGY 2014; 50:60-3. [PMID: 24842470 DOI: 10.1002/ijop.12080] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 04/19/2014] [Accepted: 04/23/2014] [Indexed: 11/07/2022]
Abstract
Individuals often hold strict and erroneous expectations for how others should grieve, yet this issue has been sparsely researched. A total of 161 undergraduates rated the appropriateness of various social and emotional behaviours of a hypothetical bereaved individual as a function of the recency of the death (1 month or 1 year ago), the nature of the loss (death of a spouse or child) and the gender of the bereaved. As expected, subjects deemed it inappropriate to show positive emotions and experiences 1 month after a hypothetical death and more inappropriate to show negative reactions 1 year later and there were generally higher expectations of socially appropriate behaviour for those who lost a child rather than a spouse. Unexpectedly, there were no significant differences regarding the gender of the bereaved. This study is among the first to show experimentally the widespread expectation that grief should be experienced early and be short-lived.
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Rejecting, accepting or merely writing about negative aspects of the self: are they different paths to the same end? INTERNATIONAL JOURNAL OF MENTAL HEALTH PROMOTION 2013. [DOI: 10.1080/14623730.2013.838040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Impact of proton beam availability on patient treatment schedule in radiation oncology. J Appl Clin Med Phys 2012; 13:3968. [PMID: 23149788 PMCID: PMC5718540 DOI: 10.1120/jacmp.v13i6.3968] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 08/12/2012] [Accepted: 07/14/2012] [Indexed: 11/25/2022] Open
Abstract
Proton beam therapy offers unique physical properties with potential for reduced toxicity and better patient care. There is an increased interest in radiation oncology centers to acquire proton therapy capabilities. The operation of a proton treatment center is quite different than a photon‐based clinic because of the more complex technology involved, as well as the single proton beam source serving multiple treatment rooms with no backup source available. There is limited published data which investigates metrics that can be used to determine the performance of a proton facility. The purpose of this study is to evaluate performance metrics of Indiana University Cyclotron Operations (IUCO), including availability, mean time between failures, and mean time to repair, and to determine how changes in these metrics impact patient treatments. We utilized a computerized maintenance management system to log all downtime occurrences and servicing operations for the facility. These data were then used to calculate the availability as well as the mean time between failures and mean time to repair. Impact on patient treatments was determined by analyzing delayed and missed treatments, which were recorded in an electronic medical record and database maintained by the therapists. The availability of the IUCO proton beam has been increasing since beginning of operation in 2003 and averaged 96.9% for 2009 through 2011. The mean time between failures and mean time to repair were also determined and correlated with improvements in the maintenance and operating procedures of the facility, as well as environmental factors. It was found that events less than 15 minutes in duration have minimal impact on treatment delays, while events lasting longer than one hour may result in missed treatments. The availability of the proton beam was more closely correlated with delayed than with missed treatments, demonstrating the utility and limitations of the availability metric. In conclusion, we suggest that the availability metric and other performance parameters, such as the mean time between failures and the mean time to repair, should be used in combination with downtime impact on patient treatments in order to adequately evaluate the operational success of a proton therapy facility. PACS number: 87.55.‐x
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Preoperative radiotherapy decreases lymph node yield of neck dissections for head and neck cancer. Otolaryngol Head Neck Surg 2012; 147:278-80. [PMID: 22460732 DOI: 10.1177/0194599812440263] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Determine if preoperative radiation therapy (RT) decreases the lymph node (LN) yield found at the time of neck dissection. STUDY DESIGN Cross-sectional analysis of Surveillance, Epidemiology, and End Results (SEER) database. METHODS The SEER database was queried for patients presenting between 1998 and 2002 with tonsil, oropharynx, hypopharynx, and laryngeal primary lesions. Tabulation was made by LNs examined, type of neck dissection performed, and timing of RT. Data from 2441 patients were retrieved. Descriptive statistics were used. RESULTS One hundred sixty-one patients with RT preoperatively had a median of 20 LNs sampled (0-72). In total, 647 patients receiving no RT had a median of 27 LNs examined (0-88), and 1643 patients receiving RT postoperatively had a median of 29 (0-89). Mann-Whitney P = .02 was derived for RT preoperatively compared with no RT/RT postoperatively. CONCLUSION In the head and neck, preoperative RT contributes to lower neck dissection LN yield.
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Structures and biosynthesis of the pyridinopyrones, polyenepyrones from a marine-derived Streptomyces species. JOURNAL OF NATURAL PRODUCTS 2011; 74:1773-8. [PMID: 21751787 PMCID: PMC3163021 DOI: 10.1021/np200323e] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Three polyenylpyrone metabolites, pyridinopyrones A to C (1-3), have been isolated from the culture broth of a marine-derived Streptomyces sp., strain CNQ-301. The structures of the pyridinopyrones were assigned on the basis of chemical modification and combined spectroscopic methods, focusing on interpretation of 1D and 2D NMR data. Pyridinopyrones B and C (2, 3), examined as an inseparable mixture of methyl positional isomers, were ultimately defined by hydrogenation and NMR analysis of a saturated derivative. The biosynthesis of these metabolites was defined by the incorporation of stable isotope-labeled precursors, revealing that the biosynthetic starter unit is nicotinic acid, while the polyene chain and pendant methyl groups are acetate- and methionine-derived, respectively.
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Spatially directed guidance of stem cell population migration by immobilized patterns of growth factors. Biomaterials 2011; 32:2775-85. [PMID: 21272933 DOI: 10.1016/j.biomaterials.2010.12.005] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Accepted: 12/01/2010] [Indexed: 01/08/2023]
Abstract
We investigated how engineered gradients of exogenous growth factors, immobilized to an extracellular matrix material, influence collective guidance of stem cell populations over extended time (>1 day) and length (>1 mm) scales in vitro. Patterns of low-to-high, high-to-low, and uniform concentrations of heparin-binding epidermal growth factor-like growth factor were inkjet printed at precise locations on fibrin substrates. Proliferation and migration responses of mesenchymal stem cells seeded at pattern origins were observed with time-lapse video microscopy and analyzed using both manual and automated computer vision-based cell tracking techniques. Based on results of established chemotaxis studies, we expected that the low-to-high gradient would most effectively direct cell guidance away from the cell source. All printed patterns, however, were found to direct net collective cell guidance with comparable responses. Our analysis revealed that collective "cell diffusion" down a cell-to-cell confinement gradient originating at the cell starting lines and not the net sum of directed individual cell migration up a growth factor concentration gradient is the principal driving force for directing mesenchymal stem cell population outgrowth from a cell source. These results suggest that simple uniform distributions of growth factors immobilized to an extracellular matrix material may be as effective in directing cell migration into a wound site as more complex patterns with concentration gradients.
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Deep enteroscopy in patients with left ventricular assist devices: practical and technical considerations. Endoscopy 2010; 42 Suppl 2:E194. [PMID: 20845267 DOI: 10.1055/s-0030-1255690] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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Inkjet-based biopatterning of bone morphogenetic protein-2 to spatially control calvarial bone formation. Tissue Eng Part A 2010; 16:1749-59. [PMID: 20028232 DOI: 10.1089/ten.tea.2009.0650] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The purpose of this study was to demonstrate spatial control of osteoblast differentiation in vitro and bone formation in vivo using inkjet bioprinting technology and to create three-dimensional persistent bio-ink patterns of bone morphogenetic protein-2 (BMP-2) and its modifiers immobilized within microporous scaffolds. Semicircular patterns of BMP-2 were printed within circular DermaMatrix human allograft scaffold constructs. The contralateral halves of the constructs were unprinted or printed with BMP-2 modifiers, including the BMP-2 inhibitor, noggin. Printed bio-ink pattern retention was validated using fluorescent or (125)I-labeled bio-inks. Mouse C2C12 progenitor cells cultured on patterned constructs differentiated in a dose-dependent fashion toward an osteoblastic fate in register to BMP-2 patterns. The fidelity of spatial restriction of osteoblastic differentiation at the boundary between neighboring BMP-2 and noggin patterns improved in comparison with patterns without noggin. Acellular DermaMatrix constructs similarly patterned with BMP-2 and noggin were then implanted into a mouse calvarial defect model. Patterns of bone formation in vivo were comparable with patterned responses of osteoblastic differentiation in vitro. These results demonstrate that three-dimensional biopatterning of a growth factor and growth factor modifier within a construct can direct cell differentiation in vitro and tissue formation in vivo in register to printed patterns.
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Abstract
A transgenic line of the pink bollworm, Pectinophora gossypiella, a key lepidopteran cotton pest, was generated previously using the piggyBac transposon IFP2 from Trichoplusia ni. Here we identified an endogenous piggyBac-like element (PLE), designated as PgPLE1, in the pink bollworm. A putatively intact copy of PgPLE1 (PgPLE1.1) presents the canonical features of PLE: inverted terminal repeats with three C/G residues at the extreme ends, inverted subterminal repeats, TTAA target site and an open reading frame encoding transposase with 68% similarity to IFP2. Vectorette PCR revealed large variation in the insertion sites of PgPLE1 amongst worldwide populations, indicating the potential mobility of PgPLE1. The PgPLE1 was undetectable in the genome of Pectinophora endema, implying the recent invasion of PgPLE1 after the divergence of these two closely related species.
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Inkjet printing of growth factor concentration gradients and combinatorial arrays immobilized on biologically-relevant substrates. Comb Chem High Throughput Screen 2009; 12:604-18. [PMID: 19601758 DOI: 10.2174/138620709788681907] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Current methods for engineering immobilized, 'solid-phase' growth factor patterns have not addressed the need for presentation of the growth factors in a biologically-relevant context. We developed an inkjet printing methodology for creating solid-phase patterns of unmodified growth factors on native biological material substrates. We demonstrate this approach by printing gradients of fluorescently labeled bone morphogenetic protein-2 (BMP-2) and insulin-like growth factor-II (IGF-II) bio-inks on fibrin-coated surfaces. Concentration gradients were created by overprinting individual substrate locations using a dilute bio-ink to modulate the surface concentration of deposited growth factor. Persistence studies using fluorescently-labeled BMP-2 verified that the gradients retained their shape for up to 7 days. Desorption experiments performed with (125)I-BMP-2 and (125)I-IGF-II were used to quantify the surface concentration of growth factor retained on the substrate for up to 10 days in serum containing media after rinsing of the unbound growth factor. The inkjet method is programmable so the gradient shape can be easily modified as demonstrated by printed linear gradients with varying slopes and exponential gradients. In addition, the versatility of this method enabled combinatorial arrays of multiple growth factors to be created by printing overlapping patterns. The overlapping printing method was used to create a combinatorial square pattern array consisting of various surface concentrations of BMP-2 and fibroblast growth factor-2 (FGF-2). C2C12 myogenic precursor cells were seeded on the arrays and alkaline phosphatase staining was performed to determine the effect of FGF-2 and BMP-2 surface concentration on guiding C2C12 cells towards an osteogenic lineage. These results demonstrate the utility of inkjet printing for creating orthogonal growth factor gradients to investigate how combinations of immobilized growth factors influence cell fate.
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Cell population tracking and lineage construction with spatiotemporal context. Med Image Anal 2008; 12:546-66. [PMID: 18656418 PMCID: PMC2670445 DOI: 10.1016/j.media.2008.06.001] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Revised: 05/16/2008] [Accepted: 06/10/2008] [Indexed: 10/21/2022]
Abstract
Automated visual-tracking of cell populations in vitro using time-lapse phase contrast microscopy enables quantitative, systematic, and high-throughput measurements of cell behaviors. These measurements include the spatiotemporal quantification of cell migration, mitosis, apoptosis, and the reconstruction of cell lineages. The combination of low signal-to-noise ratio of phase contrast microscopy images, high and varying densities of the cell cultures, topological complexities of cell shapes, and wide range of cell behaviors poses many challenges to existing tracking techniques. This paper presents a fully automated multi-target tracking system that can efficiently cope with these challenges while simultaneously tracking and analyzing thousands of cells observed using time-lapse phase contrast microscopy. The system combines bottom-up and top-down image analysis by integrating multiple collaborative modules, which exploit a fast geometric active contour tracker in conjunction with adaptive interacting multiple models (IMM) motion filtering and spatiotemporal trajectory optimization. The system, which was tested using a variety of cell populations, achieved tracking accuracy in the range of 86.9-92.5%.
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The validity of viral hepatitis and chronic liver disease diagnoses in Veterans Affairs administrative databases. Aliment Pharmacol Ther 2008; 27:274-82. [PMID: 17996017 DOI: 10.1111/j.1365-2036.2007.03572.x] [Citation(s) in RCA: 225] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND The validity of International Classification of Diseases-9 codes for liver disease has not been determined. AIM To examine the accuracy of International Classification of Diseases-9 codes for cirrhosis with hepatitis C virus or alcoholic liver disease and HIV or hepatitis B virus coinfection with hepatitis C virus in Veterans Affairs data. METHODS We conducted a retrospective study comparing the Veterans Affairs administrative data with abstracted data from the Michael E. DeBakey VA Medical Center's medical records. We calculated the positive predictive value, negative predictive value, per cent agreement and kappa. RESULTS For cirrhosis codes, the positive predictive value (probability that cirrhosis is present among those with a code) and negative predictive value (probability that cirrhosis is absent among those without a code) were 90% and 87% with 88% agreement and kappa = 0.70. For hepatitis C virus codes, the positive predictive value and negative predictive value were 93% and 92%, yielding 92% agreement and kappa = 0.78. For alcoholic liver disease codes, the positive predictive value and negative predictive value were 71% and 98%, with 89% agreement and kappa = 0.74. All parameters for HIV coinfection with hepatitis C virus were >89%; however, the codes for hepatitis B virus coinfection had a positive predictive value of 43-67%. CONCLUSION These diagnostic codes (except hepatitis B virus) in Veterans Affairs administrative data are highly predictive of the presence of these conditions in medical records and can be reliably used for research.
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Piperazimycins: cytotoxic hexadepsipeptides from a marine-derived bacterium of the genus Streptomyces. J Org Chem 2007; 72:323-30. [PMID: 17221946 DOI: 10.1021/jo061064g] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Three potent cancer cell cytotoxins, piperazimycins A-C (1-3), have been isolated from the fermentation broth of a Streptomyces sp., cultivated from marine sediments near the island of Guam. The structures of these cyclic hexadepsipeptides were assigned by a combination of spectral, chemical, and crystallographic methods. The piperazimycins are composed of rare amino acids, including hydroxyacetic acid, alpha-methylserine, gamma-hydroxypiperazic acid, and gamma-chloropiperazic acid. The novel amino acid residues 2-amino-8-methyl-4,6-nonadienoic acid and 2-amino-8-methyl-4,6-decadienoic acid were found as components of piperazimycins A and C, respectively. When screened in the National Cancer Institute's 60 cancer cell line panel, piperazimycin A exhibited potent in vitro cytotoxicity toward multiple tumor cell lines with a mean GI50 of 100 nM.
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Arenicolides A-C, 26-membered ring macrolides from the marine actinomycete Salinispora arenicola. J Org Chem 2007; 72:5025-34. [PMID: 17266372 PMCID: PMC2577615 DOI: 10.1021/jo061878x] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Chemical evaluation of the saline fermentation broth of several strains of the obligate marine actinomycete Salinispora arenicola has led to the identification of three new macrolide polyketides designated arenicolides A-C (1-3). The planar structures, elucidated via spectroscopic and chemical methods, consist of 26-membered polyunsaturated macrolactones containing repeating vicinal hydroxyl methoxyl moieties. The relative and absolute stereochemistries of 1-3 were assigned by a combination of J-based configurational analyses and chemical derivatization.
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[Diadenosine polyphosphate analogue modulates signal transduction in hippocampal slices]. FIZIOLOHICHNYI ZHURNAL (KIEV, UKRAINE : 1994) 2006; 52:9-12. [PMID: 16958210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The modulatory effect of endogenous diadenosine polyphosphates on synaptic transmission in the rat hippocampal slices has been re-examined with a non-hydrolysable Ap4A analogue diadenosine-5',5'>>-P1,P4-[beta,gamma-methylene]tetraphosphate (AppCH2ppA). We have shown that AppCH2ppA at low micromolar concentrations induce inhibition of orthodromically evoked population spikes, without affecting of excitatory postsynaptic currents and antidromic spikes recorded in the CA1 zone of hippocampus. Such a spatially selective neuronal inhibition may influence dendritic electrogenesis in pyramidal neurons and consequently mediate control of neuronal network activity in hippocampus.
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Dose-dependent cell growth in response to concentration modulated patterns of FGF-2 printed on fibrin. Biomaterials 2005; 27:2213-21. [PMID: 16325254 DOI: 10.1016/j.biomaterials.2005.10.021] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2005] [Accepted: 10/31/2005] [Indexed: 10/25/2022]
Abstract
Immobilized patterns of unmodified fibroblast growth factor-2 (FGF-2), with varying surface concentrations, were inkjet printed onto physiologically relevant fibrin substrates. Printed patterns were characterized using iodinated FGF-2 to determine FGF-2 surface concentration and retention of FGF-2 binding in vitro. MG-63 cells were uniformly seeded onto patterned substrates. Cells were exposed to defined spatial FGF-2 surface concentrations of 1-22 pg/mm(2). Cell numbers were observed to increase in register with the printed FGF-2 patterns from an initial random uniform cell distribution across the patterned and non-patterned regions. Based on time-lapse image analysis, the primary organizational response of the cells was determined to be proliferation and not migration. Cell counts on and off the FGF-2 patterns over time demonstrated an increase in cell density up to a FGF-2 surface concentration of 14 pg/mm(2). Higher surface concentrations did not result in increased cell density. In addition, the cells on the FGF-2 patterns survived longer than the cells off patterns. Our inkjet printing approach permits the systematic study of cellular responses to defined spatial surface concentrations of immobilized growth factors.
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77
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Engineered spatial patterns of FGF-2 immobilized on fibrin direct cell organization. Biomaterials 2005; 26:6762-70. [PMID: 15941581 DOI: 10.1016/j.biomaterials.2005.04.032] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2005] [Accepted: 04/12/2005] [Indexed: 01/07/2023]
Abstract
The purpose of this study was to initiate the exploration of cell behavioral responses to inkjet printed spatial patterns of hormones biologically immobilized on biomimetic substrates. This approach was investigated using the example of preosteoblastic cell response in vitro to fibroblast growth factor-2 (FGF-2) printed on fibrin films. Concentration modulated patterns of FGF-2, including continuous concentration gradients, were created by overprinting dilute FGF-2 bioinks with a custom inkjet printer. The immobilized FGF-2 was biologically active and the printed patterns persisted up to 10 days under cell culture conditions. Cell numbers increased in register to printed patterns from an initial random uniform cell distribution across the patterned and non-patterned fibrin substrate. Patterned immobilized FGF-2, not cell attachment directed cell organization because the fibrin substrate was homogeneous. The capability to engineer arbitrary and persistent hormone patterns is relevant to basic studies across various fields including developmental biology and tissue regeneration. Furthermore, since this hormone inkjet printing methodology is extensible to create complex three-dimensional structures, this methodology has potential to create therapies for tissue engineering using spatial patterned delivery of exogenous hormones.
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78
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Activation of the signal transducer and activator of transcription 1 signaling pathway in thymocytes from HIV-1-infected human thymus. AIDS 2003; 17:1269-77. [PMID: 12799548 PMCID: PMC4415361 DOI: 10.1097/00002030-200306130-00001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To identify HIV-induced host factors in the severe combined immunodeficient (SCID)-hu Thy/Liv mouse that may contribute to HIV pathogenesis in the thymus. DESIGN To identify genes specifically altered by HIV-1 infection using the cDNA microarray assay, SCID-hu Thy/Liv organs derived from the same donors were used. Therefore, no genetic variations existed between HIV and mock-infected samples. In addition, the 12-14 day post-infection timepoint was chosen because no significant thymocyte depletion was detected in HIV-infected Thy/Liv organs, so mRNA from the same cell types could be compared. METHODS Using SCID-hu Thy/Liv mice constructed from the same donor tissues, we analysed the expression of 9183 host genes in response to HIV infection with cDNA microarrays. Expression of selected genes with more than threefold induction was confirmed by measuring RNA (reverse transcriptase-polymerase chain reaction; RT-PCR) and proteins. RESULTS HIV-1 (JD or NL4-3) infection of the SCID-hu Thy/Liv mouse led to more than threefold induction of 19 genes, 12 of which were IFN-inducible and six were unknown EST clones. We confirmed induction by RT-PCR and protein blots. Both signal transducer and activator of transcription (STAT)1 and STAT2 proteins were induced, and STAT1 was also activated by phosphorylation at the Tyr701 and Ser727 sites in human thymus infected with HIV-JD or NL4-3. Treatment of human fetal thymus organ culture or human thymocytes with recombinant HIV-1 gp120 proteins also led to induction or activation of STAT1. CONCLUSION HIV-1 infection of the thymus led to activation of the STAT1 signaling pathway in thymocytes, which may contribute to HIV-1 pathogenesis in the thymus.
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79
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IMAGINING PARTNER LOSS AND MORTALITY SALIENCE: CONSEQUENCES FOR ROMANTIC-RELATIONSHIP SATISFACTION. SOCIAL BEHAVIOR AND PERSONALITY 2003. [DOI: 10.2224/sbp.2003.31.2.167] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
As hypothesized, imagining the death of one's romantic partner (for those currently involved in a romantic relationship for at least one continuous year) enhanced relationship satisfaction; unexpectedly, imagining one's own death did not markedly affect relationship satisfaction
(Experiment 1). Experiment 2 found that imagining the death of one's partner has an impact similar to imagining a positive experience with one's partner regarding relationship satisfaction. Furthermore, imagining the death of one's romantic partner causes the individual to favorably
change his/her perceptions of certain personality characteristics of the partner. Experiment 3 examined the interactive effects that certain personality traits had on imagining either the death of oneself or of one's romantic partner with respect to self-reported relation-ship satisfaction.
The applied and theoretical implications of this research are extensively discussed.
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80
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Abstract
In this paper, it is argued that a psychology of loss can help to illuminate one of the central themes of positive psychology: That is, showcasing those human skills that emphasize human strengths and optimal functioning. However, the interface of positive psychology and a psychology of loss also contains a definite paradox. Loss is not an intrinsically positive event that will necessarily build human strength. Yet, the experience of loss can become a profound means for showcasing human strengths and potential. We also caution that a positive psychology, in its quest to focus on the more uplifting qualities of the human experience, must also realize that suffering and loss is inherent to the human condition.
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81
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A leucine zipper motif in the cytoplasmic domain of gp41 is required for HIV-1 replication and pathogenesis in vivo. Virology 2001; 289:208-17. [PMID: 11689043 PMCID: PMC4435951 DOI: 10.1006/viro.2001.1112] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A leucine zipper motif is conserved in the cytoplasmic domain of glycoprotein gp41 (gp41c) of all HIV-1 subtypes, but is not present in HIV-2 or SIV. The second leucine residue of the leucine zipper was mutated (L95R) to determine the role of this motif in HIV-1 replication and pathogenesis. The L95R mutant replicated to wild-type levels in activated peripheral blood mononuclear cells and CEMx174 cells. However, L95R replication was impaired in SupT1 cells and in the SCID-hu Thy/Liv mouse. Although the infectivity of wild-type virions and that of L95R mutant virions were equally sensitive to heat treatment, we found that L95R produced more defective virions, due to reduced surface expression and virion incorporation of the env glycoprotein. These results suggest that the L95 residue in the leucine zipper of gp41c of HIV-1 plays an important role in the env expression and virion incorporation that is required for viral replication and pathogenesis in the SCID-hu Thy/Liv mouse. The leucine zipper motif in gp41c may provide a novel anti-HIV-1 target.
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82
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Decline in structural examination compliance in the hospital medical record with advancing level of training. THE JOURNAL OF THE AMERICAN OSTEOPATHIC ASSOCIATION 2001; 101:501-8. [PMID: 11575036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
A retrospective review of 115 randomly pulled hospital charts of patients admitted to the care of osteopathic physicians at an American Osteopathic Association-accredited primary care hospital revealed a significant decline in the frequency of structural examinations in history and physical examinations during a merger and relocation, as well as with increasing level of training of the examiner (chi 2 test, P < .001). Attending physicians completed fewer structural examinations (45% of their history and physical examinations) compared to house staff (70%) and students (92%). A follow-up anonymous survey of 100 osteopathic physicians and students (response rate, 58%) revealed that the low overall frequency of structural examination completion (60%) was due primarily to attending physicians who considered this examination less relevant or impractical for their hospitalized patients. These results indicate that education on relevance of structural examination and manipulative treatment for acutely ill patients needs to be directed not only to house staff and students but also to attending physicians to preserve and improve the use of osteopathic principles at osteopathic hospitals.
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83
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Human immunodeficiency virus type 1 IIIB selected for replication in vivo exhibits increased envelope glycoproteins in virions without alteration in coreceptor usage: separation of in vivo replication from macrophage tropism. J Virol 2001; 75:8498-506. [PMID: 11507195 PMCID: PMC115095 DOI: 10.1128/jvi.75.18.8498-8506.2001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Analysis of viral replication and pathogenicity after in vivo selection of human immunodeficiency virus type 1 (HIV-1) attenuated in vitro will help to define the functions involved in replication and pathogenesis in vivo. Using the SCID-hu Thy/Liv mouse and human fetal thymus organ culture as in vivo models, we previously defined HIV-1 env determinants (HXB2/LW) which were reverted for replication in vivo (L. Su et al., Virology 227:46-52, 1997). In this study, we examined the replication of four highly related HIV-1 clones directly derived from Lai/IIIB or after selection in vivo to investigate the envelope gp120 determinants associated with replication in macrophages and in the thymus models in vivo. The LW/C clone derived from the IIIB-infected laboratory worker and HXB2/LW both efficiently infected monocyte-derived macrophages (MDM) and the human thymus. Although the laboratory worker (LW) isolates showed altered tropism from IIIB, they still predominantly used CXCR4 as coreceptors for infecting peripheral blood mononuclear cells, macrophages, and the thymus. Interestingly, a single amino acid mutation in the V3 loop associated with resistance to neutralizing antibodies was also essential for the replication activity of the LW virus in the thymus models but not for its activity in infecting MDM. The LW virions were equally sensitive to a CXCR4 antagonist. We further demonstrated that the LW HIV-1 isolate selected in vivo produced more infectious viral particles that contained higher levels of the Env protein gp120. Thus, selection of the laboratory-attenuated Lai/IIIB isolate in vivo leads to altered tropism but not coreceptor usage of the virus. The acquired replication activity in vivo is correlated with an early A-to-T mutation in the V3 loop and increased virion association of HIV-1 Env gp120, but it is genetically separable from the acquired replication activity in macrophages.
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84
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Altered processing of pro-orphanin FQ/nociceptin and pro-opiomelanocortin-derived peptides in the brains of mice expressing defective prohormone convertase 2. J Neurosci 2001; 21:5864-70. [PMID: 11487609 PMCID: PMC6763138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
The bioactivity of neuropeptides can be regulated by a variety of post-translational modifications, including proteolytic processing. Here, gene-targeted mice producing defective prohormone convertase 2 (PC2) were used to examine the post-translational processing of two neuroendocrine prohormones, pro-opiomelanocortin (POMC) and pro-orphanin FQ (pOFQ)/nociceptin (N), in the brain. Reversed-phase HPLC and gel-exclusion chromatography were combined with specific radioimmunoassays to analyze the processing patterns of these two prohormones in the hypothalamus and the amygdala. In the case of POMC, the lack of PC2 activity completely prevented carboxy-shortening of beta-endorphins and greatly diminished conversion of beta-lipotropin to gamma-lipotropin and beta-endorphin. Although conversion of beta-lipotropin to beta-endorphin decreased, the lack of PC2 activity caused an increase in beta-lipotropin and beta-endorphin levels in the mutant animals, but no increases in POMC or biosynthetic intermediates were seen. The extent of OFQ/N production was significantly lower in PC2-deficient mice and there was an accumulation of relatively large amounts of pOFQ/N and biosynthetic intermediates. These results demonstrate that PC2 is directly involved in the biogenesis of two brain neuropeptides in vivo and suggest that the specific prohormone and cellular context influences neuropeptide processing by PCs.
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85
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Separation of human immunodeficiency virus type 1 replication from nef-mediated pathogenesis in the human thymus. J Virol 2001; 75:3916-24. [PMID: 11264380 PMCID: PMC114882 DOI: 10.1128/jvi.75.8.3916-3924.2001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) is frequently attenuated after long-term culture in vitro. The attenuation process probably involves mutations of functions required for replication and pathogenicity in vivo. Analysis of attenuated HIV-1 for replication and pathogenicity in vivo will help to define these functions. In this study, we examined the pathogenicity of an attenuated HIV-1 isolate in a laboratory worker accidentally exposed to a laboratory-adapted HIV-1 isolate. Using heterochimeric SCID-hu Thy/Liv mice as an in vivo model, we previously defined HIV-1 env determinants (HXB/LW) that reverted to replicate in vivo (L. Su, H. Kaneshima, M. L. Bonyhadi, R. Lee, J. Auten, A. Wolf, B. Du, L. Rabin, B. H. Hahn, E. Terwilliger, and J. M. McCune, Virology 227:46-52, 1997). Here we further demonstrate that HIV-1 replication in vivo can be separated from its pathogenic activity, in that the HXB/LW virus replicated to high levels in SCID-hu Thy/Liv mice, with no significant thymocyte depletion. Restoration of the nef gene in the recombinant HXB/LW genome restored its pathogenic activity, with no significant effect on HIV-1 replication in the thymus. Our results suggest that in vitro-attenuated HIV-1 lacks determinants for pathogenicity as well as for replication in vivo. Our data indicate that (i) the replication defect can be recovered in vivo by mutations in the env gene, without an associated pathogenic phenotype, and (ii) nef can function in the HXB/LW clone as a pathogenic factor that does not enhance HIV-1 replication in the thymus. Furthermore, the HXB/LW virus may be used to study mechanisms of HIV-1 nef-mediated pathogenesis in vivo.
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87
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Improved outcomes of veterans' compensation and pension examinations using nurse practitioners. Nurs Clin North Am 2000; 35:519-25. [PMID: 10873264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
A historic change to improve outcomes of a long-standing problem in completing veterans' compensation and pension examinations has resulted in increased access to care, higher client satisfaction, and increased system efficiencies. This article describes the change from medical care as the exclusive responsibility of physicians to an innovative use of nurse practitioners in a system that exists in a highly structured, centrally coordinated patient care practice.
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88
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Developmental changes in the neurotransmitter regulation of correlated spontaneous retinal activity. J Neurosci 2000; 20:351-60. [PMID: 10627612 PMCID: PMC6774128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Synchronized spontaneous rhythmic activity is a feature common to many parts of the developing nervous system. In the early visual system, before vision, developing circuits in the retina generate synchronized patterns of bursting activity that contain information useful for patterning connections between retinal ganglion cells and their central targets. However, how developing retinal circuits generate and regulate these spontaneous activity patterns is still incompletely understood. Here we show that in developing retinal circuits, the nature of excitatory neurotransmission driving correlated bursting activity in ganglion cells is not fixed but undergoes a developmental shift from cholinergic to glutamatergic transmission. In addition, we show that this shift occurs as presynaptic glutamatergic bipolar cells form functional connections onto the ganglion cells, implicating the role of bipolar cells in providing endogenous drive to bursting activity later in development. This transition coincides with the period when subsets of ganglion cells (On and Off cells) develop distinct activity patterns that are thought to underlie the refinement of their connectivity with their central targets. Here, our results suggest that the differences in activity patterns of On and Off ganglion cells may be conferred by differential synaptic drive from On and Off bipolar cells, respectively. Taken together, our results suggest that the regulation of patterned spontaneous activity by neurotransmitters undergoes systematic change as new cellular elements are added to developing circuits and also that these new elements can help specify distinct activity patterns appropriate for shaping connectivity patterns at later ages.
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89
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Abstract
Bipolar cells are not only important for visual processing but input from these cells may underlie the reorganization of ganglion cell dendrites in the inner plexiform layer (IPL) during development. Because little is known about the development of bipolar cells, here we have used immunocytochemical markers and dye labeling to identify and follow their differentiation in the neonatal ferret retina. Putative cone bipolar cells were immunoreacted for calbindin and recoverin, and rod bipolar cells were immunostained for protein kinase C (PKC). Our results show that calbindin-immunoreactive cone bipolar cells appear at postnatal day 15 (P15), at which time their axonal terminals are already localized to the inner half of the IPL. By contrast, recoverin-immunoreactive cells with terminals in the IPL are present at birth, but many of these cells may be immature photoreceptors. By the second postnatal week, recoverin-positive cells resembling cone bipolar cells were clearly present, and with increasing age, two distinct strata of immunolabeled processes occupied the IPL. PKC-containing rod bipolar cells emerged by the fourth postnatal week and at this age have stratified arbors in the inner IPL. The early bias of bipolar axonal arbors in terminating in the inner or outer half of the IPL is confirmed by dye labeling of cells with somata in the inner nuclear layer. At P10, several days before ribbon synapses have been previously observed in the ferret IPL, the axon terminals of all dye-labeled bipolar cells were clearly stratified. The results suggest that bipolar cells could provide spatially localized interactions that are suitable for guiding dendritic lamination in the inner retina.
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Restoration of a stem-loop structure required for potato virus X RNA accumulation indicates selection for a mismatch and a GNRA tetraloop. Virology 1999; 260:342-53. [PMID: 10417268 DOI: 10.1006/viro.1999.9843] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The 5' region of potato virus X (PVX) RNA contains a stem-loop structure, stem-loop 1 (SL1), that is required for efficient plus-strand RNA accumulation. To determine how changes to individual elements in SL1 are accommodated by the virus, we inoculated PVX transcripts containing modifications in the terminal tetraloop (TL), stem C (SC), and stem D (SD) regions onto Nicotiana benthamiana plants and analyzed progeny RNAs over a series of passages. Several progeny RNAs isolated from plants inoculated with the TL mutants containing changes to the first nucleotide of the GAAA motif or deletion of the entire TL sequence were found to contain multiple A insertions within the terminal loop region. The wild-type TL motif, GAAA, was recovered for all TL mutants by the second passage, suggesting that the sequence and potential structure of this element are crucial for PVX infection. Revertant RNAs isolated from plants inoculated with mutants in SD and the central region of SC indicated that increased stem length is tolerated. Restoration of SD length to the 4 bp typical of the wild-type PVX RNA was accompanied by A insertion into loop C. Mutants with a conversion of the C55-C78 mismatch to a G-C pair, relocation of this mismatch within the central region of SC, or deletion of C55-C78 were unable to infect protoplasts and plants. In contrast, the mutant with a conversion of the C55-C78 mismatch to an A-C mismatch, which exhibited low levels of PVX plus-strand RNA in protoplasts, was able to infect plants and quickly reverted to the wild-type C-C mismatch. These data indicate that important sequence and secondary structural elements within SL1 are required for efficient viral infection and that multiple A insertions within the TL and loop C regions, potentially by polymerase stuttering, accompany restoration of SL1 structure.
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MESH Headings
- Adenosine/genetics
- Base Pair Mismatch/genetics
- Base Pairing/genetics
- Base Sequence
- Gene Expression Regulation, Viral
- Genome, Viral
- Mutagenesis, Site-Directed
- Mutation/genetics
- Nucleic Acid Conformation
- Phenotype
- Plants, Toxic
- Potexvirus/genetics
- Potexvirus/growth & development
- Protoplasts/virology
- RNA, Messenger/chemistry
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Viral/biosynthesis
- RNA, Viral/chemistry
- RNA, Viral/genetics
- RNA, Viral/metabolism
- Thermodynamics
- Nicotiana/cytology
- Nicotiana/virology
- Virus Replication/genetics
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91
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Johns Hopkins plagiarism policies. Science 1999; 283:1265. [PMID: 10084929 DOI: 10.1126/science.283.5406.1265b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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92
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Stem-loop structure in the 5' region of potato virus X genome required for plus-strand RNA accumulation. J Mol Biol 1998; 284:591-608. [PMID: 9826501 DOI: 10.1006/jmbi.1998.2174] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Computer-generated thermodynamic predictions and solution structure probing indicated two stem-loop structures, stem-loop 1 (SL1; nt 32-106) and stem-loop 2 (SL2; nt 143-183), within the 5' 230 nt of potato virus X (PVX) RNA. Because the existence of SL1 was further supported by covariation analysis of several PVX strains, the functional significance of this structure was investigated by site-directed mutational analysis in a tobacco protoplast system. In general, mutations that reduced genomic plus-strand RNA accumulation similarly affected coat protein accumulation, indicating that subgenomic plus-strand RNA was also affected. In contrast, minus-strand RNA levels remained relatively unchanged. Mutational analysis of the stem C (SC) region of SL1 indicated that pairing was more important than sequence, which was consistent with the covariation analysis. Alterations that increased length and stability of either SC or stem D (SD) were deleterious to plus-strand RNA accumulation. The formation of internal loop C between SC and SD, as well as specific nucleotides within this loop, were also required. Several modifications were made to the terminal GAAA tetraloop, a motif known for enhanced RNA stability. Both GANA and GAAG motifs resulted in wild-type levels of RNA accumulation. However, a UUCG tetraloop was detrimental, indicating that the sequence of this element was important beyond just providing stabilization of the structure. These data indicate that multiple features of SL1 are critical for accumulation of PVX plus-strand RNA.
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93
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Abstract
A decade of research has proven that plants can be genetically engineered to resist virus infection through expression of viral CP genes, as well as other viral genes and sequences. Additional opportunities for development of resistant plants will require research focused on mechanisms of protection, improvements in expression vector design, and transformation of new crop species. As each of these technologies is utilized singly or in combination to generate resistant crop varieties, the full impact of such engineered resistance will be realized.
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94
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Exposure workups. Infect Control Hosp Epidemiol 1997; 18:850-71. [PMID: 9442409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Exposure workups are an important responsibility for infection control personnel. A well-designed plan for investigating exposures, which includes appropriate algorithms, will enable infection control personnel to evaluate exposures rapidly and consistently so that nosocomial transmission is minimized. Infection control personnel should use their own data to develop policies and procedures that suit the needs of their facility. After they have implemented the plan, infection control personnel should continue to collect data on exposures so they can continuously improve their performance.
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Should medics unionize? No! JEMS : A JOURNAL OF EMERGENCY MEDICAL SERVICES 1996; 21:37, 39-40. [PMID: 10153919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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98
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Sux debate shows process of drug education: committee chair details events. J Clin Monit Comput 1995; 11:143-4. [PMID: 7760089 DOI: 10.1007/bf01617739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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99
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Intraoperative pacemaker malfunction during total hip arthroplasty. Anesth Analg 1995; 80:410-2. [PMID: 7818133 DOI: 10.1097/00000539-199502000-00035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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100
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Abstract
To ascertain whether isoflurane produces a peripheral splanchnic sympathectomy as compared to fentanyl or pentobarbital anesthesia, 12 mongrel dogs (30-45 kg) were allocated randomly to one of three anesthetic test groups, tracheally intubated, surgically prepared, and subjected to unilateral electrical stimulation of the greater splanchnic nerve. Anesthetically, Group 1 animals (n = 4) received pentobarbital, Group 2 animals (n = 4) were administered fentanyl, and Group 3 animals (n = 4) received isoflurane. Stimulation continued for 90 min. Each second of stimulation consisted of 20 stimuli of 0.5 minimum alveolar anesthetic concentration duration and 5 V intensity, delivered during a 0.2-s interval, followed by an 0.8-s pause. To assess splanchnic sympathetic responses, mean arterial blood pressure, heart rate, pulmonary artery diastolic, cardiac output, adrenal blood flow, adrenal and arterial norepinephrine (N) and epinephrine (E) were obtained before and at 5, 10, 15, 30, 45, 60, and 90 min during stimulation. In Group 1 animals (pentobarbital), electrical stimulation elicited marked increases in mean arterial blood pressure, pulmonary artery diastolic, and cardiac output (P < 0.001). Examination of the adrenal effluent, which was exteriorized from the animal during the protocol, revealed that adrenal blood flow, adrenal vein N and E concentrations dramatically increased (P < 0.0001). Arterial N and E concentrations remained unchanged. Results of Group 2 animals (fentanyl) were similar to those of Group 1; mean arterial blood pressure, pulmonary artery diastolic, and cardiac output increased (P < 0.005). Adrenal blood flow, adrenal vein N and E increased dramatically (P < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)
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