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Gulsevin A, Glazer AM, Shields T, Kroncke BM, Roden DM, Meiler J. Veratridine Can Bind to a Site at the Mouth of the Channel Pore at Human Cardiac Sodium Channel NaV1.5. Int J Mol Sci 2022; 23:ijms23042225. [PMID: 35216338 PMCID: PMC8878851 DOI: 10.3390/ijms23042225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/07/2022] [Accepted: 02/15/2022] [Indexed: 02/05/2023] Open
Abstract
The cardiac sodium ion channel (NaV1.5) is a protein with four domains (DI-DIV), each with six transmembrane segments. Its opening and subsequent inactivation results in the brief rapid influx of Na+ ions resulting in the depolarization of cardiomyocytes. The neurotoxin veratridine (VTD) inhibits NaV1.5 inactivation resulting in longer channel opening times, and potentially fatal action potential prolongation. VTD is predicted to bind at the channel pore, but alternative binding sites have not been ruled out. To determine the binding site of VTD on NaV1.5, we perform docking calculations and high-throughput electrophysiology experiments in the present study. The docking calculations identified two distinct binding regions. The first site was in the pore, close to the binding site of NaV1.4 and NaV1.5 blocking drugs in experimental structures. The second site was at the “mouth” of the pore at the cytosolic side, partly solvent-exposed. Mutations at this site (L409, E417, and I1466) had large effects on VTD binding, while residues deeper in the pore had no effect, consistent with VTD binding at the mouth site. Overall, our results suggest a VTD binding site close to the cytoplasmic mouth of the channel pore. Binding at this alternative site might indicate an allosteric inactivation mechanism for VTD at NaV1.5.
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Affiliation(s)
- Alican Gulsevin
- Department of Chemistry, Center for Structural Biology, Vanderbilt University, Nashville, TN 37212, USA; (T.S.); (J.M.)
- Correspondence:
| | - Andrew M. Glazer
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt Center for Arrhythmia Research and Therapeutics, Vanderbilt University Medical Center, Nashville, TN 37232, USA; (A.M.G.); (B.M.K.); (D.M.R.)
| | - Tiffany Shields
- Department of Chemistry, Center for Structural Biology, Vanderbilt University, Nashville, TN 37212, USA; (T.S.); (J.M.)
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt Center for Arrhythmia Research and Therapeutics, Vanderbilt University Medical Center, Nashville, TN 37232, USA; (A.M.G.); (B.M.K.); (D.M.R.)
| | - Brett M. Kroncke
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt Center for Arrhythmia Research and Therapeutics, Vanderbilt University Medical Center, Nashville, TN 37232, USA; (A.M.G.); (B.M.K.); (D.M.R.)
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Dan M. Roden
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt Center for Arrhythmia Research and Therapeutics, Vanderbilt University Medical Center, Nashville, TN 37232, USA; (A.M.G.); (B.M.K.); (D.M.R.)
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Jens Meiler
- Department of Chemistry, Center for Structural Biology, Vanderbilt University, Nashville, TN 37212, USA; (T.S.); (J.M.)
- Institute for Drug Discovery, Leipzig University Medical School, 04103 Leipzig, Germany
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Glazer AM, Wada Y, Li B, Muhammad A, Kalash OR, O'Neill MJ, Shields T, Hall L, Short L, Blair MA, Kroncke BM, Capra JA, Roden DM. High-Throughput Reclassification of SCN5A Variants. Am J Hum Genet 2020; 107:111-123. [PMID: 32533946 PMCID: PMC7332654 DOI: 10.1016/j.ajhg.2020.05.015] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 05/19/2020] [Indexed: 12/19/2022] Open
Abstract
Partial or complete loss-of-function variants in SCN5A are the most common genetic cause of the arrhythmia disorder Brugada syndrome (BrS1). However, the pathogenicity of SCN5A variants is often unknown or disputed; 80% of the 1,390 SCN5A missense variants observed in at least one individual to date are variants of uncertain significance (VUSs). The designation of VUS is a barrier to the use of sequence data in clinical care. We selected 83 variants: 10 previously studied control variants, 10 suspected benign variants, and 63 suspected Brugada syndrome-associated variants, selected on the basis of their frequency in the general population and in individuals with Brugada syndrome. We used high-throughput automated patch clamping to study the function of the 83 variants, with the goal of reclassifying variants with functional data. The ten previously studied controls had functional properties concordant with published manual patch clamp data. All 10 suspected benign variants had wild-type-like function. 22 suspected BrS variants had loss of channel function (<10% normalized peak current) and 22 variants had partial loss of function (10%-50% normalized peak current). The previously unstudied variants were initially classified as likely benign (n = 2), likely pathogenic (n = 10), or VUSs (n = 61). After the patch clamp studies, 16 variants were benign/likely benign, 45 were pathogenic/likely pathogenic, and only 12 were still VUSs. Structural modeling identified likely mechanisms for loss of function including altered thermostability and disruptions to alpha helices, disulfide bonds, or the permeation pore. High-throughput patch clamping enabled reclassification of the majority of tested VUSs in SCN5A.
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Affiliation(s)
- Andrew M Glazer
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Yuko Wada
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Bian Li
- Department of Biological Sciences, Center for Structural Biology, and Vanderbilt Genetics Institute, Vanderbilt University, Nashville, TN 37235, USA
| | - Ayesha Muhammad
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Olivia R Kalash
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Matthew J O'Neill
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Tiffany Shields
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Lynn Hall
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Laura Short
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Marcia A Blair
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Brett M Kroncke
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - John A Capra
- Department of Biological Sciences, Center for Structural Biology, and Vanderbilt Genetics Institute, Vanderbilt University, Nashville, TN 37235, USA
| | - Dan M Roden
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
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Glazer AM, Kroncke BM, Matreyek KA, Yang T, Wada Y, Shields T, Salem JE, Fowler DM, Roden DM. Deep Mutational Scan of an SCN5A Voltage Sensor. Circ Genom Precis Med 2020; 13:e002786. [PMID: 31928070 DOI: 10.1161/circgen.119.002786] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Variants in ion channel genes have classically been studied in low throughput by patch clamping. Deep mutational scanning is a complementary approach that can simultaneously assess function of thousands of variants. METHODS We have developed and validated a method to perform a deep mutational scan of variants in SCN5A, which encodes the major voltage-gated sodium channel in the heart. We created a library of nearly all possible variants in a 36 base region of SCN5A in the S4 voltage sensor of domain IV and stably integrated the library into HEK293T cells. RESULTS In preliminary experiments, challenge with 3 drugs (veratridine, brevetoxin, and ouabain) could discriminate wild-type channels from gain- and loss-of-function pathogenic variants. High-throughput sequencing of the pre- and postdrug challenge pools was used to count the prevalence of each variant and identify variants with abnormal function. The deep mutational scan scores identified 40 putative gain-of-function and 33 putative loss-of-function variants. For 8 of 9 variants, patch clamping data were consistent with the scores. CONCLUSIONS These experiments demonstrate the accuracy of a high-throughput in vitro scan of SCN5A variant function, which can be used to identify deleterious variants in SCN5A and other ion channel genes.
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Affiliation(s)
- Andrew M Glazer
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt Center for Arrhythmia Research and Therapeutics (A.M.G., B.M.K., T.Y., Y.W., T.S., J.-E.S., D.M.R.), Vanderbilt University Medical Center, Nashville, TN
| | - Brett M Kroncke
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt Center for Arrhythmia Research and Therapeutics (A.M.G., B.M.K., T.Y., Y.W., T.S., J.-E.S., D.M.R.), Vanderbilt University Medical Center, Nashville, TN
| | - Kenneth A Matreyek
- Department of Genome Sciences, University of Washington, Seattle (K.A.M., D.M.F.)
| | - Tao Yang
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt Center for Arrhythmia Research and Therapeutics (A.M.G., B.M.K., T.Y., Y.W., T.S., J.-E.S., D.M.R.), Vanderbilt University Medical Center, Nashville, TN
| | - Yuko Wada
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt Center for Arrhythmia Research and Therapeutics (A.M.G., B.M.K., T.Y., Y.W., T.S., J.-E.S., D.M.R.), Vanderbilt University Medical Center, Nashville, TN
| | - Tiffany Shields
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt Center for Arrhythmia Research and Therapeutics (A.M.G., B.M.K., T.Y., Y.W., T.S., J.-E.S., D.M.R.), Vanderbilt University Medical Center, Nashville, TN
| | - Joe-Elie Salem
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt Center for Arrhythmia Research and Therapeutics (A.M.G., B.M.K., T.Y., Y.W., T.S., J.-E.S., D.M.R.), Vanderbilt University Medical Center, Nashville, TN.,Department of Clinical Pharmacology, APHP, Sorbonne Université, INSERM, CIC-1421, Hôpital Pitié-Salpêtrière, Paris, France (J.-E.S.)
| | - Douglas M Fowler
- Department of Genome Sciences, University of Washington, Seattle (K.A.M., D.M.F.)
| | - Dan M Roden
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt Center for Arrhythmia Research and Therapeutics (A.M.G., B.M.K., T.Y., Y.W., T.S., J.-E.S., D.M.R.), Vanderbilt University Medical Center, Nashville, TN.,Department of Biomedical Informatics (D.M.R.), Vanderbilt University Medical Center, Nashville, TN.,Department of Pharmacology (D.M.R.), Vanderbilt University Medical Center, Nashville, TN
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Vallian J, Shields T, Chung B, Tangkham W, LeMieux F. PSVI-20 Effects of castration age on growth, carcass, and sensory characteristics of Gulf Coast Native sheep. J Anim Sci 2018. [DOI: 10.1093/jas/sky404.1006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- J Vallian
- McNeese State University,Lake Charles, LA, United States
| | - T Shields
- McNeese State University,Lake Charles, LA, United States
| | - B Chung
- McNeese State University,Lake Charles, LA, United States
| | - W Tangkham
- McNeese State University,Lake Charles, LA, United States
| | - F LeMieux
- McNeese State University,Lake Charles, LA, United States
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Zenilman JM, Glass G, Shields T, Jenkins PR, Gaydos JC, McKee KT. Geographic epidemiology of gonorrhoea and chlamydia on a large military installation: application of a GIS system. Sex Transm Infect 2002; 78:40-4. [PMID: 11872858 PMCID: PMC1763689 DOI: 10.1136/sti.78.1.40] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
OBJECTIVES The geographic epidemiology of infectious diseases can help in identifying point source outbreaks, elucidating dispersion patterns, and giving direction to control strategies. We sought to establish a geographic information system (GIS) infectious disease surveillance system at a large US military post (Fort Bragg, North Carolina) using STDs as the initial outcome for the model. METHODS Addresses of incident cases were plotted onto digitised base maps of Fort Bragg (for on-post addresses) and surrounding Cumberland County, NC (for off-post addresses) using MAPINFO Version 5. We defined 26 geographic sectors on the installation. Active duty soldiers attending the post preventive medicine clinic were enrolled between July 1998 and June 1999. RESULTS Gonorrhoea (GC) was diagnosed in 210/2854 (7.4%) and chlamydia (CT) in 445/2860 (15.6%). African-American male soldiers were at higher risk for GC (OR = 4.6 (95% CL 3.0 to 7.2)) and chlamydia (OR = 2.0 (1.4 to 2.7)). For women, there were no ethnic differences in gonorrhoea prevalence, but chlamydia was higher in African-Americans (OR = 2.0 (1.4-2.7)). Rank and housing type were associated with gonorrhoea and chlamydia in men, but were not significant factors in women. For gonorrhoea, two geographic sectors had prevalences between 14.0%-16.5%, three between 10.3%-13.9%, three between 7.1%-10.2%, and five between 3.0%-7.1%. The geographic distribution demonstrated a core-like pattern where the highest sectors were contiguous and were sectors containing barracks housing lower enlisted grade personnel. In contrast, chlamydia prevalence was narrowly distributed. CONCLUSION GIS based disease surveillance was easily and rapidly implemented in this setting and should be useful in developing preventive interventions.
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Affiliation(s)
- J M Zenilman
- Division of Infectious Diseases, Johns Hopkins Medical Institutions, Baltimore, MD 21205, USA.
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Abstract
The effects of an environmental cue and smoking administration on heart rate (HR) responses to smoking were investigated in 2 studies. The 1st study was performed without smoking, to rule out the possibility that the cue manipulations alone could produce HR habituation. Thirty-six male nonsmokers were exposed to 6 trials of a changing or repeating cue (segments of a story on audiotape), followed by a paced-breathing period. HR habituation was not found. In the 2nd study, 40 male smokers smoked 4 puffs every 10 min (small-dose/long-interdose interval [IDI]) or 6 puffs every 5 min (large-dose/short-IDI) in 6 trials. The same repeating or changing cue preceded smoking. Only the repeating-cue, small-dose/long-IDI group developed HR tolerance. Modifying the cue on Trial 6 did not reverse tolerance. The results indicated that (a) tolerance to smoking appears to be subject to conditioning, (b) this effect depends on the dose and IDI, and (c) the observed tolerance is not likely to be a result of the effects of the cue alone. Nonassociative tolerance to smoking a high-dose/short-IDI did not occur in this study.
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Affiliation(s)
- L C Goulden
- Department of Psychology, Oklahoma State University, USA
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Abstract
Standard preventive therapy for inactive pulmonary tuberculosis (TB) is 12 mo of isoniazid. Shorter multiple-drug preventive regimens have been proposed. From December 1993 through January 1996 we evaluated a 4-mo, four-drug regimen of preventive therapy for patients with inactive TB, mostly newly arriving immigrants from countries with high rates of TB and of isoniazid resistance. Fifty-three evaluable patients received a 4-mo regimen of isoniazid, rifampin, ethambutol, and pyrazinamide. We compared their completion rate, side effects, and cost of treatment with those of 108 age-matched patients who had received 12 mo of isoniazid at an earlier time. Sixty-eight percent of patients on the 4-mo regimen completed treatment; 69% of those on the 12-mo regimen completed treatment (p = 0.9393). Side effects were more frequent for the 4-mo regimen (30.2%) compared with 12 mo of isoniazid (11.1%) (p = 0. 0027). The cost of providing an uncomplicated, self-supervised regimen was estimated to be almost four times greater for the four-drug regimen compared with isoniazid. These results show that, in terms of compliance, a four-drug, 4-mo regimen had no advantage over standard preventive therapy for persons with inactive pulmonary TB. On the other hand, the shorter, more intensive regimen was associated with more frequent adverse effects and was more costly.
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Affiliation(s)
- S V Goldberg
- Tuberculosis Control Program, Seattle -King County Department of Public Health, Departments of Medicine and Epidemiology, University of Washington, Seattle, Washington, USA.
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Shields T. Dutch hospitals face up to living wills. BMJ 1995; 310:82. [PMID: 7833729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Cherr GN, Fan TW, Pillai MC, Shields T, Higashi RM. Electrophoretic separation, characterization, and quantification of biologically active lignin-derived macromolecules. Anal Biochem 1993; 214:521-7. [PMID: 8109744 DOI: 10.1006/abio.1993.1533] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Degraded macromolecular lignin, which was isolated from the effluents of commercial pulp processing and known to inhibit early development in marine organisms, was separated and characterized using several polyacrylamide gel electrophoresis (PAGE) techniques. This lignin-derived macromolecule (LDM), when subjected to native PAGE and stained with alcian blue, appeared as a single band. On sodium dodecyl sulfate (SDS)-PAGE, LDM appeared to consist of two subcomponents with apparent molecular weights of 11 and < 1 kDa. When subjected to isoelectrofocusing--PAGE of pH 3-9, LDM consisted of two major bands in the basic region of the gel, with less distinct banding in the more acidic region. Two-dimensional PAGE of LDM indicated that the higher molecular weight subcomponent corresponded to the more basic constituents, while the lower molecular weight subcomponent corresponded to acidic constituents. When the two subcomponents of LDM were isolated from SDS gels by electroelution and assessed for their effects on successful fertilization and early development, the higher molecular weight subcomponent possessed most of the inhibitory activity. This is the first report of the application of a variety of electrophoretic techniques to both structurally and biologically characterize lignin-derived macromolecules.
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Affiliation(s)
- G N Cherr
- Bodega Marine Laboratory, University of California at Davis, Bodega Bay 94923
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Zhang Y, Shields T, Crenshaw T, Hao Y, Moulton T, Tycko B. Imprinting of human H19: allele-specific CpG methylation, loss of the active allele in Wilms tumor, and potential for somatic allele switching. Am J Hum Genet 1993; 53:113-24. [PMID: 8391213 PMCID: PMC1682243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Genomic imprinting and monoallelic gene expression appear to play a role in human genetic disease and tumorigenesis. The human H19 gene, at chromosome 11p15, has previously been shown to be monoallelically expressed. Since CpG methylation has been implicated in imprinting, we analyzed methylation of H19 DNA. In fetal and adult organs the transcriptionally silent H19 allele was extensively hypermethylated through the entire gene and its promoter, and, consistent with a functional role for DNA methylation, expression of an H19 promoter-reporter construct was inhibited by in vitro methylation. Gynogenetic ovarian teratomas were found to contain only hypomethylated H19 DNA, suggesting that the expressed H19 allele might be maternal. This was confirmed by analysis of 11p15 polymorphisms in a patient with Wilms tumor. The tumor had lost the maternal 11p15, and H19 expression in the normal kidney was exclusively from this allele. Imprinting of human H19 appears to be susceptible to tissue-specific modulation in somatic development; in one individual, cerebellar cells were found to express only the otherwise silent allele. Implications of these findings for the role of DNA methylation in imprinting and for H19 as a candidate imprinted tumor-suppressor gene are discussed.
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Affiliation(s)
- Y Zhang
- Department of Pathology, Columbia University, New York, NY 10032
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Bensinger W, Singer J, Appelbaum F, Lilleby K, Longin K, Rowley S, Clarke E, Clift R, Hansen J, Shields T. Autologous transplantation with peripheral blood mononuclear cells collected after administration of recombinant granulocyte stimulating factor. Blood 1993; 81:3158-63. [PMID: 7684625] [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
Peripheral blood mononuclear cells (PBMC) were collected after the administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF) and used as the sole source of hematopoietic stem cells after myeloablative therapy with busulfan (Bu) and cyclophosphamide (Cy). These studies were performed in 12 patients with malignancies (4 non-Hodgkin's lymphoma, 5 breast cancer, 1 testicular carcinoma, 1 Wilm's tumor, and 1 undifferentiated carcinoma) who had bone or bone marrow disease or had low marrow cellularity. rhG-CSF (16 micrograms/kg/d) was administered for 5 to 7 days by subcutaneous injection and PBMC were collected for 2 to 5 days beginning on day 4 after initiation of rhG-CSF, using continuous-flow blood-cell separators that processed 10 to 12 L of whole blood. From a median of three collections, a mean of 24.0 x 10(8) (+/- 10.5 SD) total nucleated cells/kg containing 12.6 x 10(8) (+/- 4.5 SD) mononuclear cells/kg, 7.3 x 10(6) (+/- 4.3 SD) CD34+ cells/kg and 20.5 x 10(4) (+/- 28.1 SD) granulocyte-macrophage colony-forming units (CFU-GM)/kg were harvested and cryopreserved. After the administration of Bu 14 to 17 mg/kg and Cy 120 to 150 mg/kg, PBMC were thawed and infused. One patient received rhG-CSF after the infusion of PBMC and the remaining 11 patients did not receive postinfusion growth factors. Mean days to recovery of neutrophil levels of 0.1, 0.5, and 1.0 x 10(9)/L were 11.4 (range, 9 to 13), 12.7 (range, 10 to 15), and 13.6 (range, 11 to 16) and the mean day to platelet transfusion independence was 13.3 (range, 7 to 49). Time to recovery of neutrophils to 0.5 and 1.0 x 10(9)/L and platelets to 20 x 10(9)/L was more rapid than in historical patients treated with Bu and Cy who received marrow alone or marrow followed by the posttransplant administration of rh-G or GM-CSF. No graft failures have been observed with a follow-up of 4 to 12 months. These results indicate that PBMC collected after rhG-CSF lead to rapid hematopoietic recovery after myeloablative chemotherapy.
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Affiliation(s)
- W Bensinger
- Fred Hutchinson Cancer Research Center, Seattle, WA 98104
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Cross SJ, Thomson L, Lee HS, Jennings K, Evans S, Shields T. Patent foramen ovale and subaqua diving: Authors' reply. West J Med 1992. [DOI: 10.1136/bmj.304.6837.1312-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Shields T, Sloane PD. A comparison of eye problems in primary care and ophthalmology practices. Fam Med 1991; 23:544-6. [PMID: 1936738] [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: 12/29/2022]
Abstract
This study compares the most frequent presenting complaints and diagnoses of eye problems in primary care physician and ophthalmologist offices sampled by the 1985 National Ambulatory Medical Care Survey. The data show that primary care patients (seen by family/general physicians, internists, and pediatricians) with eye complaints constitute 2% of all patient visits and are predominantly for minor inflammatory (58%), traumatic conditions and foreign bodies (8.4%), visual disturbances (15.5%), and eyelid problems (3.9%). Conjunctivitis and corneal abrasion accounted for 54.4% of these diagnoses. Patients see ophthalmologists predominantly for vision problems (35.5%), eye exams (24.1%), and inflammatory conditions (24%). Refractive errors, cataracts, and glaucoma constituted 52.7% of ophthalmologist diagnoses. This study provides significant implications for curricular development. Medical schools, primary care residencies, and continuing medical education settings for primary care should emphasize in-depth knowledge of minor ocular inflammatory conditions, eye trauma, visual disturbances, and eyelid problems, as these areas encompass more than 85% of the eye problems seen by primary care physicians.
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Affiliation(s)
- T Shields
- Department of Family Medicine, University of North Carolina School of Medicine, Chapel Hill 27599
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Bianco JA, Almgren J, Kern DL, Ballard B, Roark K, Andrews F, Nemunaitis J, Shields T, Singer JW. Evidence that oral pentoxifylline reverses acute renal dysfunction in bone marrow transplant recipients receiving amphotericin B and cyclosporine. Results of a pilot study. Transplantation 1991; 51:925-7. [PMID: 2014558 DOI: 10.1097/00007890-199104000-00043] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- J A Bianco
- Division of Oncology Clinical Research, Veterans Affairs Medical Center, Seattle, Washington 98108
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Goldstraw P, Bureau G, Cullen M, Dabouis G, Deneffe G, Drings P, Harper P, Lacquet L, Latto G, Pastorino U, Saunders M, Shields T, Stahel R, Turrisi A. Pretreatment minimal staging for non-small cell lung cancers: a consensus report. Lung Cancer 1991. [DOI: 10.1016/0169-5002(91)90004-p] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Contrast esophagram is the diagnostic procedure of choice in patients with clinically suspected perforation of the esophagus. In patients in whom the usual clinical signs or symptoms are unrecognized and in whom the diagnosis is obscure, the diagnosis of a perforated esophagus may be suggested by the finding of mediastinal fluid and air on CT. Three patients are reviewed. The perforations included one spontaneous, one from erosion of an esophageal carcinoma, and one iatrogenic. In two of the three patients, the diagnosis of perforated esophagus had not been made initially and in one patient the initial esophagram was interpreted as normal. Computed tomography of the chest in each patient led to the suspected diagnosis of perforated esophagus. Prompt appropriate surgical intervention followed. The findings of mediastinal fluid and more importantly mediastinal air on CT of the chest are strongly suggestive of esophageal perforation.
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Affiliation(s)
- C L Backer
- Department of Surgery, Northwestern University Medical School, Chicago
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