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Jang GM, Annan Sudarsan AK, Shayeganmehr A, Prando Munhoz E, Lao R, Gaba A, Granadillo Rodríguez M, Love RP, Polacco BJ, Zhou Y, Krogan NJ, Kaake RM, Chelico L. Protein Interaction Map of APOBEC3 Enzyme Family Reveals Deamination-Independent Role in Cellular Function. Mol Cell Proteomics 2024; 23:100755. [PMID: 38548018 PMCID: PMC11070599 DOI: 10.1016/j.mcpro.2024.100755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 03/13/2024] [Accepted: 03/25/2024] [Indexed: 04/09/2024] Open
Abstract
Human APOBEC3 enzymes are a family of single-stranded (ss)DNA and RNA cytidine deaminases that act as part of the intrinsic immunity against viruses and retroelements. These enzymes deaminate cytosine to form uracil which can functionally inactivate or cause degradation of viral or retroelement genomes. In addition, APOBEC3s have deamination-independent antiviral activity through protein and nucleic acid interactions. If expression levels are misregulated, some APOBEC3 enzymes can access the human genome leading to deamination and mutagenesis, contributing to cancer initiation and evolution. While APOBEC3 enzymes are known to interact with large ribonucleoprotein complexes, the function and RNA dependence are not entirely understood. To further understand their cellular roles, we determined by affinity purification mass spectrometry (AP-MS) the protein interaction network for the human APOBEC3 enzymes and mapped a diverse set of protein-protein and protein-RNA mediated interactions. Our analysis identified novel RNA-mediated interactions between APOBEC3C, APOBEC3H Haplotype I and II, and APOBEC3G with spliceosome proteins, and APOBEC3G and APOBEC3H Haplotype I with proteins involved in tRNA methylation and ncRNA export from the nucleus. In addition, we identified RNA-independent protein-protein interactions with APOBEC3B, APOBEC3D, and APOBEC3F and the prefoldin family of protein-folding chaperones. Interaction between prefoldin 5 (PFD5) and APOBEC3B disrupted the ability of PFD5 to induce degradation of the oncogene cMyc, implicating the APOBEC3B protein interaction network in cancer. Altogether, the results uncover novel functions and interactions of the APOBEC3 family and suggest they may have fundamental roles in cellular RNA biology, their protein-protein interactions are not redundant, and there are protein-protein interactions with tumor suppressors, suggesting a role in cancer biology. Data are available via ProteomeXchange with the identifier PXD044275.
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Affiliation(s)
- Gwendolyn M Jang
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, USA; Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, California, USA; J. David Gladstone Institutes, Gladstone Institute for Data Science and Biotechnology, San Francisco, California, USA
| | - Arun Kumar Annan Sudarsan
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Arzhang Shayeganmehr
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Erika Prando Munhoz
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Reanna Lao
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, USA; Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, California, USA; J. David Gladstone Institutes, Gladstone Institute for Data Science and Biotechnology, San Francisco, California, USA
| | - Amit Gaba
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Milaid Granadillo Rodríguez
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Robin P Love
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Benjamin J Polacco
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, USA; Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, California, USA
| | - Yuan Zhou
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, USA; J. David Gladstone Institutes, Gladstone Institute for Data Science and Biotechnology, San Francisco, California, USA
| | - Nevan J Krogan
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, USA; Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, California, USA; J. David Gladstone Institutes, Gladstone Institute for Data Science and Biotechnology, San Francisco, California, USA
| | - Robyn M Kaake
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, USA; Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, California, USA; J. David Gladstone Institutes, Gladstone Institute for Data Science and Biotechnology, San Francisco, California, USA.
| | - Linda Chelico
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
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Jang GM, Sudarsan AKA, Shayeganmehr A, Munhoz EP, Lao R, Gaba A, Rodríguez MG, Love RP, Polacco BJ, Zhou Y, Krogan NJ, Kaake RM, Chelico L. Protein interaction map of APOBEC3 enzyme family reveals deamination-independent role in cellular function. bioRxiv 2024:2024.02.06.579137. [PMID: 38370690 PMCID: PMC10871184 DOI: 10.1101/2024.02.06.579137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Human APOBEC3 enzymes are a family of single-stranded (ss)DNA and RNA cytidine deaminases that act as part of the intrinsic immunity against viruses and retroelements. These enzymes deaminate cytosine to form uracil which can functionally inactivate or cause degradation of viral or retroelement genomes. In addition, APOBEC3s have deamination independent antiviral activity through protein and nucleic acid interactions. If expression levels are misregulated, some APOBEC3 enzymes can access the human genome leading to deamination and mutagenesis, contributing to cancer initiation and evolution. While APOBEC3 enzymes are known to interact with large ribonucleoprotein complexes, the function and RNA dependence is not entirely understood. To further understand their cellular roles, we determined by affinity purification mass spectrometry (AP-MS) the protein interaction network for the human APOBEC3 enzymes and map a diverse set of protein-protein and protein-RNA mediated interactions. Our analysis identified novel RNA-mediated interactions between APOBEC3C, APOBEC3H Haplotype I and II, and APOBEC3G with spliceosome proteins, and APOBEC3G and APOBEC3H Haplotype I with proteins involved in tRNA methylation and ncRNA export from the nucleus. In addition, we identified RNA-independent protein-protein interactions with APOBEC3B, APOBEC3D, and APOBEC3F and the prefoldin family of protein folding chaperones. Interaction between prefoldin 5 (PFD5) and APOBEC3B disrupted the ability of PFD5 to induce degradation of the oncogene cMyc, implicating the APOBEC3B protein interaction network in cancer. Altogether, the results uncover novel functions and interactions of the APOBEC3 family and suggest they may have fundamental roles in cellular RNA biology, their protein-protein interactions are not redundant, and there are protein-protein interactions with tumor suppressors, suggesting a role in cancer biology.
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Affiliation(s)
- Gwendolyn M. Jang
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA, 94158, USA
- Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, CA, 94158, USA
- J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Arun Kumar Annan Sudarsan
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
- Current Address: Centre for Commercialization of Regenerative Medicine (CCRM), 661 University Ave #1002, Toronto, ON M5G 1M1
| | - Arzhang Shayeganmehr
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
| | - Erika Prando Munhoz
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
- Current Address: Department of Medicine, Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW Calgary, AB T2N 4N1
| | - Reanna Lao
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA, 94158, USA
- Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, CA, 94158, USA
- J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Amit Gaba
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
| | - Milaid Granadillo Rodríguez
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
| | - Robin P. Love
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
- Current Address: Faculty of Medicine & Dentistry, Department of Medicine, TB Program Evaluation & Research Unit, University of Alberta, 11402 University Avenue NW, Edmonton, AB, T6G 2J3
| | - Benjamin J. Polacco
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA, 94158, USA
- Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, CA, 94158, USA
| | - Yuan Zhou
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA, 94158, USA
- J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Nevan J. Krogan
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA, 94158, USA
- Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, CA, 94158, USA
- J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Robyn M. Kaake
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA, 94158, USA
- Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, CA, 94158, USA
- J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Linda Chelico
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
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Ullah E, Wu D, Madireddy L, Lao R, Ling-Fung Tang P, Wan E, Bardakjian T, Kopinsky S, Kwok PY, Schneider A, Baranzini S, Ansar M, Slavotinek A. Two missense mutations in SALL4 in a patient with microphthalmia, coloboma, and optic nerve hypoplasia. Ophthalmic Genet 2016; 38:371-375. [PMID: 27661448 DOI: 10.1080/13816810.2016.1217550] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
To investigate the genetic etiology of anophthalmia and microphthalmia, we used exome sequencing in a Caucasian female with unilateral microphthalmia and coloboma, bilateral optic nerve hypoplasia, ventricular and atrial septal defects, and growth delays. We found two sequence variants in SALL4 - c.[575C>A], predicting p.(Ala192Glu), that was paternally inherited, and c.[2053G>C], predicting p.(Asp685His), that was maternally inherited. Haploinsufficiency for SALL4 due to nonsense or frameshift mutations has been associated with acro-renal ocular syndrome that is characterized by eye defects including Duane anomaly and coloboma, in addition to radial ray malformations and renal abnormalities. Our report is the first description of structural eye defects associated with two missense variants in SALL4 inherited in trans; the absence of reported findings in both parents suggests that both sequence variants are hypomorphic mutations and that both are needed for the ocular phenotype. SALL4 is expressed in the developing lens and regulates BMP4, leading us to speculate that altered BMP4 expression was responsible for the eye defects, but we could not demonstrate altered BMP4 expression in vitro after using small interfering RNAs (siRNAs) to reduce SALL4 expression. We conclude that SALL4 hypomorphic variants may influence eye development.
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Affiliation(s)
- E Ullah
- a Department of Pediatrics , University of California, San Francisco , San Francisco , California , USA.,b Department of Biochemistry, Faculty of Biological Sciences , Quaid-i-Azam University , Islamabad , Pakistan
| | - D Wu
- a Department of Pediatrics , University of California, San Francisco , San Francisco , California , USA
| | - L Madireddy
- c Department of Neurology , University of California, San Francisco , San Francisco , California , USA
| | - R Lao
- d Cardiovascular Research Institute , University of California, San Francisco , San Francisco , California , USA
| | - P Ling-Fung Tang
- d Cardiovascular Research Institute , University of California, San Francisco , San Francisco , California , USA
| | - E Wan
- d Cardiovascular Research Institute , University of California, San Francisco , San Francisco , California , USA
| | - T Bardakjian
- e Division of Medical Genetics , Einstein Healthcare Network , Philadelphia , Pennsylvania , USA
| | - S Kopinsky
- e Division of Medical Genetics , Einstein Healthcare Network , Philadelphia , Pennsylvania , USA
| | - P-Y Kwok
- d Cardiovascular Research Institute , University of California, San Francisco , San Francisco , California , USA
| | - A Schneider
- e Division of Medical Genetics , Einstein Healthcare Network , Philadelphia , Pennsylvania , USA
| | - S Baranzini
- c Department of Neurology , University of California, San Francisco , San Francisco , California , USA
| | - M Ansar
- b Department of Biochemistry, Faculty of Biological Sciences , Quaid-i-Azam University , Islamabad , Pakistan
| | - A Slavotinek
- a Department of Pediatrics , University of California, San Francisco , San Francisco , California , USA
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Slavotinek AM, Garcia ST, Chandratillake G, Bardakjian T, Ullah E, Wu D, Umeda K, Lao R, Tang PLF, Wan E, Madireddy L, Lyalina S, Mendelsohn BA, Dugan S, Tirch J, Tischler R, Harris J, Clark MJ, Chervitz S, Patwardhan A, West JM, Ursell P, de Alba Campomanes A, Schneider A, Kwok PY, Baranzini S, Chen RO. Exome sequencing in 32 patients with anophthalmia/microphthalmia and developmental eye defects. Clin Genet 2015; 88:468-73. [PMID: 25457163 DOI: 10.1111/cge.12543] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [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: 09/18/2014] [Revised: 11/09/2014] [Accepted: 11/19/2014] [Indexed: 12/17/2022]
Abstract
Anophthalmia/microphthalmia (A/M) is a genetically heterogeneous birth defect for which the etiology is unknown in more than 50% of patients. We used exome sequencing with the ACE Exome(TM) (Personalis, Inc; 18 cases) and UCSF Genomics Core (21 cases) to sequence 28 patients with A/M and four patients with varied developmental eye defects. In the 28 patients with A/M, we identified de novo mutations in three patients (OTX2, p.(Gln91His), RARB, p.Arg387Cys and GDF6, p.Ala249Glu) and inherited mutations in STRA6 in two patients. In patients with developmental eye defects, a female with cataracts and cardiomyopathy had a de novo COL4A1 mutation, p.(Gly773Arg), expanding the phenotype associated with COL4A1 to include cardiomyopathy. A male with a chorioretinal defect, microcephaly, seizures and sensorineural deafness had two PNPT1 mutations, p.(Ala507Ser) and c.401-1G>A, and we describe eye defects associated with this gene for the first time. Exome sequencing was efficient for identifying mutations in pathogenic genes for which there is no clinical testing available and for identifying cases that expand phenotypic spectra, such as the PNPT1 and COL4A1-associated disorders described here.
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Affiliation(s)
- A M Slavotinek
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA.,Program in Human Genetics, University of California San Francisco, San Francisco, CA, USA
| | | | | | - T Bardakjian
- Division of Medical Genetics, Einstein Medical Center, Philadelphia, PA, USA
| | - E Ullah
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA.,Department of Biochemistry, Quaid-i-Azam University, Islamabad, Pakistan
| | - D Wu
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA
| | - K Umeda
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA
| | - R Lao
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, USA
| | - P L-F Tang
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, USA
| | - E Wan
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, USA
| | - L Madireddy
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - S Lyalina
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - B A Mendelsohn
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA
| | - S Dugan
- Division of Medical Genetics, Children's Hospitals & Clinics, Minneapolis, MN, USA
| | - J Tirch
- Personalis, Inc., Menlo Park, CA, USA
| | | | - J Harris
- Personalis, Inc., Menlo Park, CA, USA
| | - M J Clark
- Personalis, Inc., Menlo Park, CA, USA
| | | | | | - J M West
- Personalis, Inc., Menlo Park, CA, USA
| | - P Ursell
- Department of Pathology, University of California San Francisco, San Francisco, CA, USA
| | - A de Alba Campomanes
- Department of Ophthalmology, University of California San Francisco, San Francisco, CA, USA
| | - A Schneider
- Division of Medical Genetics, Einstein Medical Center, Philadelphia, PA, USA
| | - P-Y Kwok
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, USA
| | - S Baranzini
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - R O Chen
- Personalis, Inc., Menlo Park, CA, USA
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Xu T, Xu Y, Lao R, He K, Xue L, Goldkorn A. Mouse prostate tumor inhibition via disruption of murine telomerase: In vivo and in vitro data for a new preclinical cancer model. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.e14631] [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
e14631 Background: Telomerase-interference (TI), a novel therapeutic strategy, exploits the high telomerase activity in prostate cancer by introducing a mutated telomerase RNA (MT-Ter) that encodes toxic telomeres. Until now, TI has been tested by targeting human telomerase in tumor cells xenografted into immuno-deficient mice, an inadequate model for predicting efficacy and toxicity. We designed and validated 2 new TI gene constructs that specifically target murine telomerase RNA (mTER), enabling the study of TI in preclinical mouse models that are immuno-competent and that develop endogenous prostate tumors. Methods: We designed 2 constructs and cloned them into a lentiviral delivery system: MT-mTER and siRNA against wild type mTer (α-mTer-siRNA). Using a mouse prostate cancer cell line, E4, we tested the 2 constructs for expression (RT-PCR), telomerase activity (TRAP), and biologic activity (53bp1 DNA damage staining, MTS growth assay, TUNEL and caspase apoptosis assays), as well as in vivo efficacy (NOD-SCID allografts). Results: We confirmed MT-mTER expression (∼50-fold) and showed that α-mTer-siRNA specifically depleted WT-mTER (80% reduction) but not MT-mTER when the 2 constructs are co-expressed; thus, the 2 constructs in combination effectively substituted MT-mTer for WT-mTer in the mouse prostate cancer cells. MT-mTER caused mutant telomeric repeats (TTTGGG instead of TTAGGG) to be added to the ends of telomeres, resulting in rapid telomeric uncapping marked by 53bp1 DNA damage foci (an average 7.5 foci/cell vs. 1.4 foci/cell in vector control). This, in turn, led to rapid and significant apoptosis (>90% TUNEL and caspase +) and growth inhibition in vitro (90% reduction by MTS) and in vivo (75% reduction in tumor allograft size). Conclusions: We successfully designed and validated MT-mTer and α-mTer-siRNA, 2 novel gene constructs that specifically target and co-opt murine telomerase activity within mouse prostate cancer cells. These constructs offer a significant advantage, as they can be used to investigate TI in immuno-competent mice that develop prostate cancer, thereby modeling actual human disease and testing TI-based therapies in a much more informative and authentic manner. No significant financial relationships to disclose.
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Affiliation(s)
- T. Xu
- University of Southern California, Los Angeles, CA
| | - Y. Xu
- University of Southern California, Los Angeles, CA
| | - R. Lao
- University of Southern California, Los Angeles, CA
| | - K. He
- University of Southern California, Los Angeles, CA
| | - L. Xue
- University of Southern California, Los Angeles, CA
| | - A. Goldkorn
- University of Southern California, Los Angeles, CA
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Abstract
Acute right ventricular dysfunction has been established both as a diagnostic and prognostic indicator in pulmonary embolism. This report illustrates the utility of thallium-201 scintigraphy as an adjunctive noninvasive test in the diagnosis of pulmonary embolism by demonstrating increases in regional right ventricular perfusion and its subsequent resolution with treatment presumably as a result of decreased pressure work.
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Affiliation(s)
- R R Jasani
- Division of Pulmonary and Critical Care, Newark Beth Israel Medical Center, NJ 07112, USA
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Favorov OV, Hester JT, Lao R, Tommerdahl M. Spurious dynamics in somatosensory cortex. Behav Brain Res 2002; 135:75-82. [PMID: 12356437 DOI: 10.1016/s0166-4328(02)00158-4] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Cortical networks are dynamical systems whose task is to process information. However, in addition to 'intended' dynamical behaviors, the sheer complexity of a cortical network's structure-regardless of its precise details-should generate additional 'unintended' dynamical behaviors. Dynamics observed in cortical network models and in the somatosensory cortex suggest that such spurious dynamical behaviors are likely to be pervasive but relatively simple, contributing to-rather than dominating-a network's response to stimuli. Spurious dynamics may be responsible for a variety of experimentally observed intriguing features of cortical dynamics. Because of their distributed origins and emergent nature, such dynamical features, while clearly identifiable, will resist attempts at identifying specific mechanisms to explain them. We describe some of the spurious dynamical phenomena associated with somatosensory cortical response to brushing stimulation, to illustrate how spurious dynamics can affect neurons' functional properties, cortical stimulus representation and, ultimately, perception.
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Affiliation(s)
- O V Favorov
- School of Electrical Engineering and Computer Science, University of Central Florida, Orlando, FL 32816, USA.
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8
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Shapiro RS, Wagreich J, Parsons RB, Stancato-Pasik A, Yeh HC, Lao R. Tissue harmonic imaging sonography: evaluation of image quality compared with conventional sonography. AJR Am J Roentgenol 1998; 171:1203-6. [PMID: 9798848 DOI: 10.2214/ajr.171.5.9798848] [Citation(s) in RCA: 203] [Impact Index Per Article: 7.8] [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: 12/24/2022]
Abstract
OBJECTIVE The purpose of this study was to determine if tissue harmonic imaging (THI) sonography produced higher quality images than did conventional sonography. SUBJECTS AND METHODS A prospective study was performed on 89 patients to compare the image quality of THI sonography with that of conventional sonography. Each examination was performed using THI sonography (transmitted frequency, 2.0 MHz; received frequency, 4.0 MHz) and conventional sonography at 2.5 and 4.0 MHz. The pancreatic area was studied in 60 patients, and other anatomic areas were studied in 68 patients. The images were then graded for penetration, detail, and total image quality. Graders were unaware of the sonographic technique. RESULTS Of the 60 pancreatic examinations, THI sonography was the best technique for penetration in 45, detail in 54, and total image quality in 50. For the pancreas, THI sonography was significantly better than 2.5-MHz conventional sonography for penetration (p = .0002), detail (p < .0001), and total image quality (p < .0001). THI sonography was significantly better than 4.0-MHz conventional sonography for penetration (p < .0001), detail (p < .0001), and total image quality (p < .0001). Of the 68 examinations of other anatomic areas, THI sonography was the best technique for penetration in 42, detail in 57, and total image quality in 58. For other anatomic areas, THI sonography was significantly better than 2.5-MHz conventional sonography for penetration (p = .05), detail (p < .0001), and total image quality (p < .0001). THI sonography was significantly better than 4.0-MHz conventional sonography for penetration (p < .0001), detail (p < .0001), and total image quality (p < .0001). CONCLUSION The THI technique improved sonographic image quality.
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Affiliation(s)
- R S Shapiro
- Department of Radiology, Mount Sinai Medical Center, New York, NY 10029-6574, USA
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Abstract
The incidence and pathogenesis of right ventricular dysfunction in obstructive sleep apnoea (OSA) remains controversial. Using nuclear ventriculography, the prevalence of right ventricular dysfunction (RVD) was therefore determined in obese patients with OSA, as well as their clinical characteristics, arterial blood gas values, spirometry and sleep parameters. The reversibility of RVD was evaluated after long-term use of nasal continuous positive airway pressure (nCPAP). We studied 112 obese patients with OSA by nuclear ventriculography, 35 with RVD (Group 1), 77 without RVD (Group 2), and 14 patients without OSA as controls (Group 3). Repeat nuclear ventriculography was performed in seven patients who used nCPAP nightly for 6-24 months. The mean right ventricular ejection fractions (RVEF) were 31%, 47% and 44% in Groups 1, 2 and 3, respectively. Group 1 also had a lower left ventricular ejection fraction (LVEF) of 55 vs 63% in Group 2. The OSA groups did not differ in mean spirometric or arterial blood gas values. Group 1 had a lower mean nocturnal arterial oxygen saturation (Sa,O2) of 82 vs 87% in Group 2, and a longer apnoea duration of 22.3 vs 19.2 s. All but two patients in Group 1 had either awake alveolar hypoventilation or an apnoea + hypopnoea index > 40 disordered breathing events.h-1. Repeat nuclear ventriculography after nCPAP revealed an increase in RVEF from 30 to 39%. In conclusion, right ventricular dysfunction is common in obstructive sleep apnoea, but it is reversible with nasal continuous positive airway pressure treatment and appears to be related to nocturnal oxygen desaturation.
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Affiliation(s)
- J Nahmias
- Newark Beth Israel Medical Center, New Jersey 07112, USA
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10
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Abstract
Gallium is presently used in the diagnosis of inflammatory, granulomatous, and neoplastic lung disease despite its many logistical problems. In contrast, thallium-201 scintigraphy, which was initially developed for myocardial imaging, offers the principal advantage of immediate imaging and diagnosis although it had not been investigated previously for use in pulmonary disease. In this study, thallium and gallium were prospectively compared with each other for the diagnosis of a variety of lung diseases. The overall concordance rate was 75%. Thallium was found to be significantly more sensitive than gallium for the entire group studied (N = 51, p < 0.006). In a subset of patients in whom a firm diagnosis was established, thallium was also found to be more sensitive, 86% vs 64%. The greater sensitivity of thallium-201 and its several inherent advantages suggest that thallium-201 should replace gallium-67 citrate as the radioisotope of choice for nuclear imaging of the chest.
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Affiliation(s)
- J A Miller
- Department of Pulmonary Medicine, Newark Beth Israel Medical Center, NJ
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11
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Weinberg RS, Thomson JC, Lao R, Chen G, Alter BP. Stem cell factor amplifies newborn and sickle erythropoiesis in liquid cultures. Blood 1993; 81:2591-9. [PMID: 7683924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
A two-phase liquid-culture system was used to substantially amplify and differentiate erythroblasts, starting with mononuclear cells from the blood of normal adults, newborn infants, and patients with sickle cell anemia. After the first 7 days (phase 1), in medium plus fetal bovine serum (FBS) alone, or in combination with stem cell factor (SCF) or conditioned medium (CM), the cell number was unchanged, and the cells all looked like lymphocytes. These cells were then diluted into medium with erythropoietin (Ep) alone, with Ep and either SCF or CM, or in methylcellulose with the same factors (phase 2). After 14 days in liquid phase 2 with SCF and Ep, the cell numbers increased an average of 30-fold in the sickle, 24-fold in the newborn, and 4-fold in the normal adult cultures; almost all the cells were erythroblasts and erythrocytes. SCF in phase 1 increased the number of late progenitors (CFU-E) assayed in methylcellulose, with the largest number in sickle, followed by newborn cultures and then adult cultures. We conclude that erythroid progenitor cells survive for at least 7 days without Ep (but with FBS). Progenitor cells are amplified, particularly with SCF. Later in culture, SCF with Ep increases the final number of differentiated erythroid cells. Both the early and the late effects of SCF are most effective in sickle, followed by newborn cultures and then adult cultures.
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Affiliation(s)
- R S Weinberg
- Polly Annenberg Levee Hematology Center, Department of Medicine, Mount Sinai School of Medicine, New York, NY 10029
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