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Chen CL, Huang JY, Wang CH, Tahara SM, Zhou L, Kondo Y, Schechter J, Su L, Lai MMC, Wakita T, Cosset FL, Jung JU, Machida K. Hepatitis C virus has a genetically determined lymphotropism through co-receptor B7.2. Nat Commun 2017; 8:13882. [PMID: 28067225 PMCID: PMC5227552 DOI: 10.1038/ncomms13882] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [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: 08/16/2016] [Accepted: 11/08/2016] [Indexed: 12/18/2022] Open
Abstract
B-cell infection by hepatitis C virus (HCV) has been a controversial topic. To examine whether HCV has a genetically determined lymphotropism through a co-receptor specific for the infection by lymphotropic HCV, we established an infectious clone and chimeric virus of hepatotropic and lymphotropic HCV strains derived from an HCV-positive B-cell lymphoma. The viral envelope and 5'-UTR sequences of the lymphotropic HCV strain were responsible for the lymphotropism. Silencing of the virus sensor, RIGI, or overexpression of microRNA-122 promoted persistent viral replication in B cells. By cDNA library screening, we identified an immune cell-specific, co-stimulatory receptor B7.2 (CD86) as a co-receptor of lymphotropic HCV. Infection of B cells by HCV inhibited the recall reaction to antigen stimulation. Together, a co-receptor B7.2 enabled lymphotropic HCV to infect memory B cells, leading to inhibition of memory B-cell function and persistent HCV infection in HCV-infected hosts.
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Affiliation(s)
- Chia-Lin Chen
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Avenue, Los Angeles, California 90033, USA
| | - Jeffrey Y. Huang
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Avenue, Los Angeles, California 90033, USA
| | - Chun-Hsiang Wang
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Avenue, Los Angeles, California 90033, USA
| | - Stanley M Tahara
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Avenue, Los Angeles, California 90033, USA
| | - Lin Zhou
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Avenue, Los Angeles, California 90033, USA
| | - Yasuteru Kondo
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Avenue, Los Angeles, California 90033, USA
| | - Joel Schechter
- Department of Cell and Neurobiology, Keck School of Medicine, University of Southern California, 2011 Zonal Avenue, Los Angeles, California 90033, USA
| | - Lishan Su
- Department of Microbiology and Immunology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7290, USA
| | - Michael M C. Lai
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Avenue, Los Angeles, California 90033, USA
- Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan
| | - Takaji Wakita
- Department of Virology II, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
| | - François-Loïc Cosset
- International Center for Infectiology Research, Team EVIR, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Univ Lyon, F-69007 Lyon, France
| | - Jae U Jung
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Avenue, Los Angeles, California 90033, USA
| | - Keigo Machida
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Avenue, Los Angeles, California 90033, USA
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Schechter J, Araujo G, Dodd J. B-99Failed Effort Testing, Post-Concussion Symptoms, and Number of School Days Missed following Pediatric Mild Traumatic Brain Injury. Arch Clin Neuropsychol 2015. [DOI: 10.1093/arclin/acv047.194] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Fiori K, Schechter J, Houndeno S. Global health delivery science: Applying the care delivery value
framework to a community based HIV/AIDS initiative in Togo, West
Africa. Ann Glob Health 2015. [DOI: 10.1016/j.aogh.2015.02.936] [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: 11/24/2022] Open
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Nath P, Nelson B, Davoudiasl H, Dutta B, Feldman D, Liu Z, Han T, Langacker P, Mohapatra R, Valle J, Pilaftsis A, Zerwas D, AbdusSalam S, Adam-Bourdarios C, Aguilar-Saavedra J, Allanach B, Altunkaynak B, Anchordoqui LA, Baer H, Bajc B, Buchmueller O, Carena M, Cavanaugh R, Chang S, Choi K, Csáki C, Dawson S, de Campos F, De Roeck A, Dührssen M, Éboli O, Ellis J, Flächer H, Goldberg H, Grimus W, Haisch U, Heinemeyer S, Hirsch M, Holmes M, Ibrahim T, Isidori G, Kane G, Kong K, Lafaye R, Landsberg G, Lavoura L, Lee JS, Lee SJ, Lisanti M, Lüst D, Magro M, Mahbubani R, Malinsky M, Maltoni F, Morisi S, Mühlleitner M, Mukhopadhyaya B, Neubert M, Olive K, Perez G, Pérez PF, Plehn T, Pontón E, Porod W, Quevedo F, Rauch M, Restrepo D, Rizzo T, Romão J, Ronga F, Santiago J, Schechter J, Senjanović G, Shao J, Spira M, Stieberger S, Sullivan Z, Tait TM, Tata X, Taylor T, Toharia M, Wacker J, Wagner C, Wang LT, Weiglein G, Zeppenfeld D, Zurek K. The Hunt for New Physics at the Large Hadron Collider. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.nuclphysbps.2010.03.001] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Sullivan M, Elliott D, Schechter J, Taylor C. Development of a career pathways program to help students with specialty choices. Med Teach 2009; 31:871. [PMID: 19830895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Luo Q, Cheng X, Holroyd T, Majestic C, Schechter J, Blair RJR. Emotional automaticity? It is a matter of timing --- spatiotemporal dynamics of the amygdala in the gamma band. Neuroimage 2009. [DOI: 10.1016/s1053-8119(09)72013-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Goebert D, Thompson D, Takeshita J, Beach C, Bryson P, Ephgrave K, Kent A, Kunkel M, Schechter J, Tate J. Depressive symptoms in medical students and residents: a multischool study. Acad Med 2009; 84:236-41. [PMID: 19174678 DOI: 10.1097/acm.0b013e31819391bb] [Citation(s) in RCA: 256] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
BACKGROUND This multisite, anonymous study assessed depressive symptoms and suicidal ideation in medical trainees (medical students and residents). METHOD In 2003-2004, the authors surveyed medical trainees at six sites. Surveys included content from the Center for Epidemiologic Studies-Depression scale (CES-D) and the Primary Care Evaluation of Mental Disorders (PRIME-MD) (measures for depression), as well as demographic content. Rates of reported major and minor depression and of suicidal ideation were calculated. Responses were compared by level of training, gender, and ethnicity. RESULTS More than 2,000 medical students and residents responded, for an overall response rate of 89%. Based on categorical levels from the CES-D, 12% had probable major depression and 9.2% had probable mild/moderate depression. There were significant differences in depression by trainee level, with a higher rate among medical students; and gender, with higher rates among women (chi2 = 10.42, df = 2, and P = .005 and chi2 = 22.1, df = 2, and P < .001, respectively). Nearly 6% reported suicidal ideation, with differences by trainee level, with a higher rate among medical students; and ethnicity, with the highest rate among black/African American respondents and the lowest among Caucasian respondents (chi2 = 5.19, df = 1, and P = .023 and chi2 = 10.42, df = 3, and P = .015, respectively). CONCLUSIONS Depression remains a significant issue for medical trainees. This study highlights the importance of ongoing mental health assessment, treatment, and education for medical trainees.
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Affiliation(s)
- Deborah Goebert
- Department of Psychiatry, University of Hawaii John A. Burns School of Medicine, Honolulu, Hawaii 96813, USA.
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Abstract
Previous studies have shown that ovariectomy causes necrosis of lacrimal acinar cells, apoptosis of plasma cells and gland lymphocytic infiltration. Both, lacrimal gland cell death and lymphocytic infiltration were prevented by androgen treatment. Since estrogens are removed by ovariectomy, and the synthetic estrogen diethylstilbestrol has been shown to affect some biochemical correlates of lacrimal secretion, the purpose of this study was to determine the effect of 17-beta-estradiol treatment on ovariectomy-induced cell death and lymphocytic infiltration. Sexually mature female New Zealand white rabbits (4-4.5 kg) were ovariectomized and divided into two groups. One group was treated with 0.5 mg kg(-1) per day 17-beta-estradiol, and the other group with vehicle alone. A third group of sham operated rabbits was used as controls and they also were treated with vehicle alone. Six days after surgery, the animals were euthanized, the lacrimal glands removed and processed for analysis of apoptosis as assessed by DNA fragmentation, and for morphological examination. DNA fragmentation was determined using the TUNEL assay and agarose gel electrophoresis. Sections were also stained for rabbit thymic lymphocyte antigen (RTLA), and rabbit CD18. Labelled nuclei and stained areas were quantified by automated densitometry. Ovariectomized rabbits showed a significant increase in the values for degraded DNA as a percent of total nuclear area (2.90+/-0.40%) compared to sham operated rabbits (0.73+/-0.22%). 17-beta-estradiol treatment in ovariectomized rabbits prevented the increase in DNA degradation. Examination of TUNEL assay at higher magnification (40x) confirmed previous studies showing that ovariectomy caused apoptosis of interstitial cells. Significant numbers of bulging cells of very pale appearance under light microscopy, also confirm previously identified necrotic cells in acinar regions. Treatment with 17-beta-estradiol prevented this necrosis. Increased numbers of RTLA(+) and CD18(+) interstitial cells were also evident after ovariectomy. 17-beta-estradiol treatment prevented the increase in the number of lymphoid cells. We confirmed previous observations that suggest that glandular atrophy observed after ovariectomy is likely to proceed by necrosis of acinar cells rather than apoptosis, and that ovariectomy triggers an inflammatory response in the gland. These results suggest that in addition to androgens, estrogens also seem to play a role to maintain lacrimal gland structure and function. A decrease in available estrogen levels could trigger both lacrimal gland apoptosis and necrosis, as well as lymphocytic infiltration. Although, the effect of estrogens in these experiments seems to be direct and not through androgens, the possibility of the role of an autocrine and/or paracrine factors, promoted by estrogen on lacrimal gland cells still needs to be investigated.
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Affiliation(s)
- Ana Maria Azzarolo
- Department of Biomedical Science, Charles E. Schmidt College of Science Center, Florida Atlantic University, Bldg 71, Room 145, 777 Glades Rd., P.O. Box 3091, Boca Raton, FL 33431-0991, USA.
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Schechter J, Stevenson D, Chang D, Chang N, Pidgeon M, Nakamura T, Okamoto CT, Trousdale MD, Mircheff AK. Growth of purified lacrimal acinar cells in Matrigel raft cultures. Exp Eye Res 2002; 74:349-60. [PMID: 12014916 DOI: 10.1006/exer.2001.1158] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The objective of this study was to develop a tissue culture system which closely mimics the in situ lacrimal gland for improved study of lacrimal acinar cell physiology. Highly purified preparations of lacrimal acinar cells from adult female New Zealand White rabbits were isolated and grown in suspension culture in the form of Matrigel 'rafts', i.e., aggregates of acinar cells enclosed within a Matrigel coating. The rafts were seeded onto Matrigel-coated culture plates and their growth was followed for up to 28 days. Immunohistochemistry was used to demonstrate the cellular sites of prolactin (PRL), epidermal growth factor (EGF), basic fibroblast growth factor (FGF-2), secretory component (SC) and major histocompatibility complex class-II molecules (MHC-II) within the acinar cells. By 3 days the cultures contained numerous, well-formed acini enclosed within the Matrigel. The acinar epithelial cells demonstrated histotypic polarity, with large, pale-staining, secretory granules aggregated adjacent to the lumen, and exocytotic release of secretory material into the lumen. From 5-10 days the pale-staining secretory granules decreased in number, while the lumenal contents of the acini increased in staining density. Throughout the culturing period as the pale-staining, secretory granules decreased in number, smaller more densely stained, secretory granules increased in number. The number of cells and size of acinar clusters increased steadily throughout the culturing period, and acini frequently achieved dimensions in excess of 0.5 mm. Increases in the size of acinar clusters were often accompanied by an increase in the size of the lumen. Frequently the lumen and its contents bulged asymmetrically towards one edge of the acinus. Immunhistochemistry demonstrated PRL and EGF within the lumens and within the apical cytoplasm of the acinar cells. Acini were strongly immunopositive for SC throughout the 28 day culture period, whereas immunopositivity for MHC-II molecules was strong initially, but diminished dramatically by 21 days. Immunostaining for FGF-2 was most intense on days 1 and 3, with staining throughout the cytoplasm, but became progressively more localized to the periphery of the acini as the culture period lengthened. In cultures of 1-28 days duration, Western blots of cell lysates demonstrated a major band (approximately 40 kDa) for PRL in 3-28 day preparations; a major band (approximately 80 kDa) for SC in 3 day and 7 day preparations that decreased in intensity in 14-28 day preparations; and a major band (approximately 23 kDa) for MHC-II protein in 1-21 day preparations that decreased in intensity in 28 day preparations. Lysosomes increased in number with time in culture, becoming a dominant cytoplasmic feature in 21 and 28 day cultures. Carbachol stimulation of 4 day rafts resulted in increased release of beta-hexosaminidase and SC from the rafts. The authors conclude that Matrigel rafts containing purified lacrimal gland acinar cells offer a highly advantageous system for study of lacrimal acinar cell function and one that correlates well with the in situ gland.
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Affiliation(s)
- Joel Schechter
- Department of Cell and Neurobiology, The Keck School of Medicine, University of Southern California, Los Angeles, CA 90089-9112, USA.
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Sivin I, Wan L, Ranta S, Alvarez F, Brache V, Mishell DR, Darney P, Biswas A, Diaz S, Kiriwat O, Anant MP, Klaisle C, Pavez M, Schechter J. Levonorgestrel concentrations during 7 years of continuous use of Jadelle contraceptive implants. Contraception 2001; 64:43-9. [PMID: 11535213 DOI: 10.1016/s0010-7824(01)00226-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Serum levonorgestrel concentrations were assayed in a multicenter, 7-year study of 199 users of Jadelle rod implants. We examined drug levels, patterns of changes, factors affecting drug levels, and concentrations at which pregnancies occurred. Mean levonorgestrel concentrations declined from 435 pg/mL at 1 month of use to 64% of that value (280 pg/mL) at the end of 3 years. Between the end of the third and fifth years neither mean nor median serum levels varied markedly. At 5 years the mean concentration was again 64% of the first month's mean. Declining levels were observed thereafter through the end of 7 years when the mean, 224 pg/mL, was 52% of the 1-month value. Last measured drug concentrations of women who became pregnant during Jadelle use had mean and median values of 152 and 144 pg/mL, respectively, and a maximum value of 180 pg/mL. Analyses indicated ponderal index, body weight, duration of use, and a single clinical center were the most important variables affecting measured levonorgestrel levels. Approximately one-third of assays in the sixth and seventh years were found to be below 180 pg/mL, suggesting that Jadelle levonorgestrel implants would not maintain sufficiently high levels of effectiveness against pregnancy after 5 years and that heavier women would then be at greater risk of pregnancy.
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Affiliation(s)
- I Sivin
- Center for Biomedical Research, Population Council, New York, NY, USA.
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Schechter J, Carey J, Wallace M, Wood R. Distribution of growth factors and immune cells are altered in the lacrimal gland during pregnancy and lactation. Exp Eye Res 2000; 71:129-42. [PMID: 10930318 DOI: 10.1006/exer.2000.0859] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have undertaken a series of studies to elucidate the roles of growth factors (FGF-2, EGF, TGF-beta1) and prolactin (PRL) in lacrimal gland function during pregnancy and lactation, and to better understand the status of the immune system within the lacrimal gland during those physiological states. In this initial study, lacrimal glands of pregnant (d15, d29), lactating (9d, 22d), and adult female control rabbits, were evaluated by immunohistochemistry, Western blotting and image analysis. In control rabbits EGF, TGF-beta1, and PRL, were immunolocalized primarily in the apical cytoplasm of intralobular ductal epithelial cells, and acini demonstrated a basement membrane-associated immunopositivity for TGF-beta1. FGF-2 immunolocalized in myoepithelial cells in the basal ductal epithelium and complexed to the basement membrane enclosing ducts and acini. Cells immunopositive for immune cell markers (RTLA and CD18) were apparent primarily around interlobular ducts. In d29 pregnant rabbits immunopositivity for EGF and TGF-beta1 was increased within intralobular ducts, both apically and basally, and within some interlobular ductal epithelial cells. Immunopositivity for PRL was strongest in d29 pregnant rabbits within the apical and basal cytoplasm of intralobular ductal epithelial cells. Immunopositivity for FGF-2 in myoepithelial cells was strong in d15 and d29 pregnant rabbits, although basement membrane-associated immunopositivity around acini was often decreased. Immunostaining for EGF and TGF-beta1 in lactating rabbits was similar to that in d29 pregnant rabbits, although basement membrane-associated immunopositivity around acini was more comparable to controls. By 22d lactation immunopositivity for FGF-2 closely resembled that in controls. Image analysis of pregnant and lactating rabbits demonstrated that cells immunopositive for RTLA and CD18 were less abundant around ducts and more abundant between acini, although in 22d lactating rabbits the size of periductal foci was increased to nearly that of controls. Western blots correlated well with the immunohistochemistry. Our findings demonstrate that pregnancy and lactation are accompanied by a shift in the distributions of growth factors and PRL, suggestive of increased release both apically into the lacrimal fluid and basally into the interstitium. Additional shifts in the distributions of cells of the immune system from periductal foci to interacinar sites suggest that there is a recruitment of immune cells away from ducts and toward the connective tissue interstitium surrounding the acini, possibly as part of a heightened state of immune readiness during pregnancy and lactation.
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Affiliation(s)
- J Schechter
- Department of Cell and Neurobiology, University of Southern California School of Medicine, Los Angeles 90089-9112, USA
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Schechter J, Wallace M, Carey J, Chang N, Trousdale M, Wood R. Corneal insult affects the production and distribution of FGF-2 within the lacrimal gland. Exp Eye Res 2000; 70:777-84. [PMID: 10843782 DOI: 10.1006/exer.2000.0837] [Citation(s) in RCA: 12] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The purpose of this study was to determine the distribution of FGF-2 within rabbit lacrimal glands and to determine whether corneal insult affects that distribution. The scarified corneas of experimental animals were inoculated either with adenovirus type 5 or buffer. Control animals were either untreated, or animals whose corneas were scarified. Twenty-one days later all animals were killed and the lacrimal glands were studied by immunocytochemistry and Western blotting to detect FGF-2. In untreated control animals, FGF-2 was immunolocalized predominantly within a population of elongated cells in the basal epithelium of ducts, and to a lesser degree in the basal epithelium of the acini. The elongated immunopositive cells appear to be myoepithelial cells known to be present at these sites. Interstitial cells around ducts and acini, and the basement membranes of the ducts and acini, were also immunopositive for FGF-2. Twenty-one days after adenovirus inoculation and scarification of the cornea, immunopositivity for FGF-2 was dramatically decreased in basement membranes, but increased within myoepithelial cells of the duct epithelium. These myoepithelial cells were frequently enlarged, bulging toward the duct lumen. In animals whose corneas were inoculated with buffer and scarified, or animals whose corneas were simply scarified, the changes in the lacrimal gland were similar, but somewhat less pronounced, to those of adenovirus-inoculated animals. Western blots confirmed the presence of FGF-2 immunoreactivity in all groups. The major band in untreated controls was at 24 kD, whereas all animals with corneal scarification had major bands at 38 kD. Densitometry of Western blots demonstrated that the amount of 24 kD FGF-2 present within the lacrimal gland after corneal scarification was at least 50% less than in untreated controls, whereas 38 kD FGF-2 was at least ten-fold greater. Our findings indicate that corneal scarification results in an altered distribution of FGF-2 within the lacrimal gland, which involves a decrease in low molecular weight FGF-2 and a dramatic increase in a higher molecular weight isoform of FGF-2. FGF-2 may be released from myoepithelial cells apically (exocrine) into the tear fluid and basally (autocrine/paracrine) into the connective tissue, as well as from extracellular complexes within basal laminae.
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Affiliation(s)
- J Schechter
- Department of Cell and Neurobiology, University of Southern California School of Medicine, Los Angeles, CA 90033, USA
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Sivin I, Mishell DR, Diaz S, Biswas A, Alvarez F, Darney P, Holma P, Wan L, Brache V, Kiriwat O, Abdalla K, Campodonico I, Pasquale S, Pavez M, Schechter J. Prolonged effectiveness of Norplant(R) capsule implants: a 7-year study. Contraception 2000; 61:187-94. [PMID: 10827332 DOI: 10.1016/s0010-7824(00)00095-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Soft tubing Norplant(R) contraceptive implants were studied in 1210 women for 7 years to measure the duration of effectiveness and the magnitude of the pregnancy rates over that time. Mean age at enrollment was 27.4 years. Of the enrollees, 42% were US residents. One-sixth (16.1%) weighed >/=70 kg at the time of implant placement. At the end of 5 years, the cumulative pregnancy rate was 1.1/100; at the end of 7 years, it was 1.9/100. No pregnancies occurred to any of the 400 women who enrolled in the study at age >/=30 years and who weighed <100 kg. Among women aged 18-33 years, the 7-year Norplant pregnancy rates are comparable to the median pregnancy rates of tubal sterilization methods for women of the same age and duration of use. For women aged >/=34 years, without regard to weight at admission, the 7-year effectiveness of soft tubing Norplant equals or surpasses that of tubal sterilization. For continuing implant users, annual pregnancy rates <1.0/100 in years 6 and 7, together with low cumulative pregnancy rates, testify that Norplant capsule implants remain highly effective for 7 years.
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Affiliation(s)
- I Sivin
- Center for Biomedical Research, Population Council, New York, New York 10021, USA
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Abstract
Traditionally, cutaneous malignant melanoma is regarded as a radioresistant tumor. Recently, however, an increasing number of clinical studies have refuted this notion. The authors examined the role of radiation therapy in the palliative and/or adjuvant treatment of cutaneous malignant melanoma. The records of 69 patients with cutaneous malignant melanoma were reviewed. Twenty-five patients with extensive regional lymph node involvement received adjuvant radiation therapy after primary surgical treatment, and the remainder received palliative radiation therapy. The therapeutic significance of fraction size was analyzed. In the palliative radiation therapy group, the response rate was 52% with a fraction size < or = 300 cGy and 35% with a larger fraction size (p > 0.05, NS). Local regional control rates after adjuvant radiation therapy using conventional fractionation and larger fraction size were 87% and 82%, respectively (p > 0.05, NS). Radiation therapy is effective in the management of cutaneous malignant melanoma. It plays an important role in the palliation of metastatic disease and as an adjuvant treatment. No advantage in using a large fraction size over conventional dose schedules was found.
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Affiliation(s)
- E Fenig
- Institute of Oncology, Rabin Medical Center, Beilinson Campus, Petah Tiqva, Israel
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Affiliation(s)
- J Schechter
- Department of Cell and Neurobiology, University of Southern California School of Medicine, Los Angeles, USA
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Schechter J, Green LW, Olsen L, Kruse K, Cargo M. Application of Karasek's demand/control model a Canadian occupational setting including shift workers during a period of reorganization and downsizing. Am J Health Promot 1997; 11:394-9. [PMID: 10168257 DOI: 10.4278/0890-1171-11.6.394] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [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
PURPOSE To apply Karasek's Job Content Model to an analysis of the relationships between job type and perceived stress and stress behaviors in a large company during a period of reorganization and downsizing. DESIGN Cross-sectional mail-out, mail-back survey. SETTING A large Canadian telephone/telecommunications company. SUBJECTS Stratified random sample (stratified by job category) of 2200 out of 13,000 employees with a response rate of 48.8%. MEASURES Responses to 25 of Karasek's core questions were utilized to define four job types: low-demand and high control = "relaxed"; high demand and high control = "active"; low demand and low control = "passive", and high demand and low control = "high strain." These job types were compared against self-reported stress levels, perceived general level of health, absenteeism, alcohol use, exercise level, and use of medications and drugs. Similar analyses were performed to assess the influence of shift work. RESULTS Employees with "passive" or "high strain" job types reported higher levels of stress (trend test p < .0001); poorer health (trend test P = .006); and higher levels of absenteeism (trend test p < .0001). More shift workers reported themselves in poor or fair health (chi-square p = .018) and reported high levels of stress at home (chi-square p = .002) than nonshift workers. The relationships between job type and levels of stress, health and absenteeism, however, held for nonshift workers as well. CONCLUSIONS Job types with high demand and low control were associated with increased stress, increased absenteeism, and poorer self-concept of health. The demand/control model of Karasek and Theorell was validated in this setting with respect to stress and some stress-associated attitudes and behaviors.
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Affiliation(s)
- J Schechter
- University of British Columbia, Vancouver, Canada
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Harada M, Schechter J. Effects of symmetry breaking on the strong and electroweak interactions of the vector nonet. Phys Rev D Part Fields 1996; 54:3394-3413. [PMID: 10021012 DOI: 10.1103/physrevd.54.3394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Abstract
BACKGROUND Basic fibroblast growth factor (FGF-2), a potent angiogenic peptide, is known to be present in gonadotropes of the anterior pituitary parenchyma of rats and mice, and has been isolated from endothelial cells of many organs. Its localization within endothelial cells has not been determined, nor the mechanisms by which it might be released from endothelial cells during normal organogenesis. METHODS Localization of FGF within endothelial cells of the anterior pituitary was accomplished by immunocytochemistry and studied by light- and electron microscopy. Capillaries within the anterior pituitary were studied in fetal rats from day 15 to term, and in adult rats. RESULTS At the onset stages of vascularization (15-18 days fetal), the cytoplasm of the endothelial cells of many of the invading, immature capillaries (thick-walled with few or no fenestrations) was intensely immunopositive for FGF. Immunoprecipitate-filled blebs and slender cytoplasmic processes projected from the endothelial cells into the presumptive pericapillary space and toward the parenchymal cells. As gestation progressed (19-20 day fetal), and an increasing number of capillaries acquired the features characteristic of capillaries in the anterior pituitary of adult animals, i.e., thin-walled and fenestrated, there were fewer capillaries demonstrating immunopositivity for FGF. Foci of released FGF, i.e., extracellular, were occasionally evident within the presumptive pericapillary spaces throughout gestation. By comparison, capillaries of the anterior pituitary of adult rats did not contain immunostainable FGF in their cytoplasm, nor were any blebs and/or processes filled with immunoprecipitate evident. However capillaries did reveal an immunopositive enhancement of their lumenal and ablumenal surfaces. CONCLUSIONS During vascularization of the anterior pituitary, FGF within the cytoplasm of endothelial cells is released from blebs and/or processes of endothelial cells, and after the capillary bed is stabilized postnatally, these characteristics of vascularization are absent.
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Affiliation(s)
- J Schechter
- Department of Cell and Neurobiology, University of Southern California School of Medicine, Los Angeles, USA
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Schechter J, Weigel H. Resolving ordering ambiguities in the collective quantization by particle conjugation constraints. Phys Rev D Part Fields 1995; 51:6296-6307. [PMID: 10018393 DOI: 10.1103/physrevd.51.6296] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Schechter J, Stauber C, Windle JJ, Mellon P. Basic fibroblast growth factor: the neurotrophic factor influencing the ingrowth of neural tissue into the anterior pituitary of alpha-T7 transgenic mice? Neuroendocrinology 1995; 61:622-7. [PMID: 7659188 DOI: 10.1159/000126888] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
alpha-T7 mice are a transgenic line which carries a hybrid transgene composed of the 5' flanking region of the human glycoprotein hormone alpha-subunit gene (1.8 kb) linked to the coding region of the oncogene SV40 T-antigen. Large, hemorrhagic, pituitary tumors form in these mice and contain giant, transformed gonadotropes (immunopositive for T-antigen), in addition to normal-appearing gonadotropes (also immunopositive for T-antigen). An additional feature of these tumors is an abundance of neural tissue proliferating throughout the anterior pituitary, concentrated around the giant gonadotropes, and forming synaptoid contacts upon them. Continued study of these mice has demonstrated that the giant gonadotropes contain immunostainable basic fibroblast growth factor (FGF-2), and apparently release the FGF by focal cellular disruption and/or cytoplasmic blebbing. Normal gonadotropes, in control and transgenic mice, were strongly immunopositive for FGF, and appeared intact. In 8- to 13-month-old transgenic mice most of the giant cells were intact, and were surrounded by well-differentiated neural tissue. These giant cells were lightly immunopositive for FGF. Disrupted, giant gonadotropes were more frequent in 2- to 7-month-old transgenic mice, and also were surrounded by well-differentiated neural tissue with many synaptoid contacts. These cells generally were moderately immunopositive for FGF. In neonatal mice, 1-8 days old, precursors of the giant, transformed gonadotropes were identified, primarily, but not exclusively, near the periphery of the anterior pituitary.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J Schechter
- Department of Cell and Neurobiology, University of Southern California, School of Medicine, Los Angeles 90033, USA
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Momen A, Schechter J, Subbaraman A. Heavy quark solitons: Strangeness and symmetry breaking. Phys Rev D Part Fields 1994; 49:5970-5978. [PMID: 10016924 DOI: 10.1103/physrevd.49.5970] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Schechter J, Subbaraman A, Weigel H. Effective hadron dynamics: From meson masses to the proton spin puzzle. Phys Rev D Part Fields 1993; 48:339-355. [PMID: 10016087 DOI: 10.1103/physrevd.48.339] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Schechter J, Subbaraman A. Role of light vector mesons in the heavy particle chiral Lagrangian. Phys Rev D Part Fields 1993; 48:332-338. [PMID: 10016086 DOI: 10.1103/physrevd.48.332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Abstract
Pituitary tumorigenesis occurs in a transgenic line of mice, alpha-T7, which carries a hybrid transgene composed of the 5' flanking region of the human glycoprotein hormone alpha-subunit gene (1.8 kb) linked to the coding region of the SV40 T-antigen gene (alpha-Tag). Tumor foci were identified within the anterior pituitary of both male and female transgenic mice. In addition to a parenchyma with hypertrophied endocrine cells, mostly of the gonadotrope lineage, we here report the unexpected presence of neural tissue within the anterior pituitary, either as foci as large as 1.0 mm in diameter or greater, or in delicate bundles ramifying amongst the granulated parenchymal cells. Areas richest in neural tissue frequently were associated with tumor tissue composed of giant cells of three varieties, all with electron-lucent cytoplasm and similar organellar distribution including small secretory granules (80-160 nm diameter). In type I cells, the secretory granules were aligned at the plasma membrane; in type II cells, the secretory granules were distributed throughout the cytoplasm; type III cells formed colloid-filled follicles and their secretory granules rarely exceeded 100 nm diameter. These giant cells frequently had bizarre pleomorphic nuclei intensely immunopositive for T-antigen and cytoplasm which was lightly immunopositive for alpha-subunit, and immunopositive either for the LH-beta or TSH-beta subunits. Neural tissue contacted the normal granulated parenchymal cells directly, i.e., without a basal lamina or any connective tissue intervening, but only rarely formed synaptoid junctions with these granulated cells. Synaptoid junctions containing round, smooth vesicles, as well as dense core vesicles, were numerous between the neural processes themselves and between the neural tissue and the giant cells of the tumor tissue. These data suggest that in alpha-T7 transgenic mice the giant cells represent highly transformed gonadotropes or thyrotropes, and that a neurotrophic factor may be expressed by these transformed pituitary parenchymal cells.
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Affiliation(s)
- J Schechter
- Department of Anatomy and Cell Biology, University of Southern California School of Medicine, Los Angeles 90033
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Schechter J, Weiner R. A model for the role of basic fibroblast growth factor in pituitary tumorigenesis. Ann N Y Acad Sci 1991; 638:503-4. [PMID: 1785830 DOI: 10.1111/j.1749-6632.1991.tb49082.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- J Schechter
- Department of Anatomy and Cell Biology, University of Southern California, Los Angeles 90033
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Schechter J, Weiner R. Changes in basic fibroblast growth factor coincident with estradiol-induced hyperplasia of the anterior pituitaries of Fischer 344 and Sprague-Dawley rats. Endocrinology 1991; 129:2400-8. [PMID: 1935774 DOI: 10.1210/endo-129-5-2400] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Adult female Fischer 344 (F344) and Sprague-Dawley (SD) rats were treated with estradiol via Silastic implants for 10 and 20 days. This treatment period in F344 rats is sufficient to produce dramatic hyperplasia of anterior pituitary lactotropes, activation of folliculo-stellate cells (FS) as phagocytes, and reorganization of the blood supply, i.e. hemorrhagic lakes and arteriogenesis from vessels in the adjacent meninges. Estradiol-treated SD rats do not demonstrate a comparable response. We now report intense focal concentrations of cells immunopositive for basic fibroblast growth factor (FGF) in estradiol-treated F344 rats predominantly near the posterolateral edge of the anterior pituitary, a zone rich in gonadotropes and lactotropes. Immunostaining for FGF, by both light and electron microscopy, revealed that the immunopositive cells were gonadotropes, and that the immunoprecipitate was cytosolic and was most abundant in the cytosol facing the capillaries. Immunostaining for extracellular matrix-associated FGF also revealed foci of positivity at the postero-lateral edge. Estradiol-treated SD rats did not reveal comparable localization for FGF. Morphological analysis and immunolocalization of S-100 protein, a marker for FS cells, revealed that the periphery of the anterior pituitary of estradiol-treated F344 rats included numerous disrupted gonadotropes and, furthermore, was largely devoid of FS cells. This zone was more intact in control F344 rats, but lacked FS cells. The peripheral parenchyma of control and estradiol-treated SD rats was intact compared to that of F344 rats and consistently included FS cells. These results suggest that disruptions of gonadotropes at the pituitary periphery may release FGF, which could then stimulate angiogenesis from blood vessels within the adjacent meninges. The resultant systemic blood supply would stimulate lactotrope hypertrophy and hyperplasia. Since FS cells are known phagocytes within the anterior pituitary, their absence from the periphery of F344 rats may intensify or prolong the effect of the peripherally released FGF.
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Affiliation(s)
- J Schechter
- Department of Anatomy and Cell Biology, University of Southern California School of Medicine, Los Angeles 90033
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Pattison A, Pattison T, Schechter J. Pars distalis vasculature: Discovery Shuttle STS-29 rats compared to ground-based antiorthostatic rats. Anat Rec (Hoboken) 1991; 231:347-50. [PMID: 1763816 DOI: 10.1002/ar.1092310308] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The anterior pituitary glands of male, adult Long Evans rats carried 5 days in the Space Shuttle Discovery (STS-29) have been compared with two groups of ground-based controls. All of the animals were part of a study (SE82-08) into the effects of gravity versus a microgravity environment on fracture healing. All had sustained a right, mid-shaft fibular osteotomy. The duration of the study was 10 days, and animals in all groups were weight bearing for the 5 days prior to shuttle lift off. The three experimental groups consisted of four rats each: flight (F) and two ground-based control groups, weight bearing (WB) and suspended (S). The suspension group was in a Holton/Sweeney head-down suspension apparatus (antiorthostatic) for the final 5 days of the study. The anterior pituitary glands of F and WB rats were essentially identical. The vasculature and parenchymal cells appeared unaffected in both instances. However, the anterior pituitary glands of S rats were dramatically altered. The vasculature was widely expanded with proteinaceous deposition covering the lumenal endothelial surfaces, and entrapping numerous platelets and aggregates of red blood cells. Parenchymal cells were highly vacuolated, occasionally with membranous vacuoles, but most often revealing large, clear cytoplasmic zones unlined by any membranes. Whereas profiles of exocytosis were numerous in F rats, and present in WB rats, they were essentially absent in S rats. These results indicate that weightlessness over a 5-day flight period does not influence the structural integrity of the anterior pituitary gland and may in fact promote secretory granule release. However, the head-down tilt model, frequently used to study fracture repair under conditions that mimic weightlessness, has a profound impact on the vasculature of the anterior pituitary gland which then affects the structural and functional characteristics of the parenchymal cells.
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Affiliation(s)
- A Pattison
- Department of Anatomy and Cell Biology, University of Southern California School of Medicine, Los Angeles 90033
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Park NW, Schechter J, Weigel H. Electromagnetic, axial-vector, and strange currents in the Skyrme model: Effects of symmetry breaking. Phys Rev D Part Fields 1991; 43:869-884. [PMID: 10013449 DOI: 10.1103/physrevd.43.869] [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] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Schechter J, Soni V, Subbaraman A, Weigel H. Two-component approach to the "proton spin" puzzle in generalized Skyrme models. Phys Rev Lett 1990; 65:2955-2958. [PMID: 10042742 DOI: 10.1103/physrevlett.65.2955] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Johnson R, Park NW, Schechter J, Soni V, Weigel H. Singlet axial-vector current and the "proton-spin" question. Phys Rev D Part Fields 1990; 42:2998-3009. [PMID: 10013182 DOI: 10.1103/physrevd.42.2998] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Hornstein L, Lederer G, Schechter J, Greenberg Z, Boem R, Bilguray B, Giladi L, Hamburger J. Persistent Schistosoma mansoni infection in Yemeni immigrants to Israel. Isr J Med Sci 1990; 26:386-9. [PMID: 2117600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Following sporadic reports on persistent Schistosoma mansoni (S.m) infections in Israelis of Yemeni origin, we systematically surveyed a group of 129 individuals who immigrated to Israel 38 years ago. Physical examination was uneventful in all members of the study group. A single stool examination revealed S.m eggs in 15 of 129 subjects (12%). Specific anti-S.m. IgE was detected in the sera of 48 individuals (37%). Among the 15 egg-positives, 14 had specific IgE (sensitivity 93.3%), but only 80 of the 114 egg-negatives were also negative for specific IgE (specificity 70%). This specific IgE positivity among egg-negatives in the study group (34/114) and its complete absence from two control groups, one of them comprising Yemenites born in Israel, suggest either an S.m infection with low egg output stemming from a low worm burden or low fecundity of senescent worms, or occult infections. Since the S.m infections could not have been contracted in Israel, our findings point to inordinately persistent infections in the members of our study group, and incidentally also to the diagnostic usefulness of specific IgE testing in such cases.
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Affiliation(s)
- L Hornstein
- Immunology Laboratory, Lady Davis Carmel Hospital, Haifa, Israel
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Park NW, Schechter J, Weigel H. Symmetry breaking and hyperon decays in the Skyrme model. Phys Rev D Part Fields 1990; 41:2836-2843. [PMID: 10012677 DOI: 10.1103/physrevd.41.2836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Jain P, Johnson R, Park NW, Schechter J, Weigel H. Neutron-proton mass-splitting puzzle in Skyrme and chiral quark models. Phys Rev D Part Fields 1989; 40:855-865. [PMID: 10011885 DOI: 10.1103/physrevd.40.855] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Meissner UG, Kaiser N, Weigel H, Schechter J. Erratum: Realistic pseudoscalar-vector Lagrangian. Static and dynamical baryon properties. Int J Clin Exp Med 1989; 40:262. [PMID: 10011681 DOI: 10.1103/physrevd.40.262] [Citation(s) in RCA: 7] [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: 11/07/2022]
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Meissner UG, Kaiser N, Weigel H, Schechter J. Realistic pseudoscalar-vector Lagrangian. Static and dynamical baryon properties. Phys Rev D Part Fields 1989; 39:1956-1972. [PMID: 9959869 DOI: 10.1103/physrevd.39.1956] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Schechter J, Ahmad N, Weiner R. Activation of anterior pituitary folliculo-stellate cells in the formation of estrogen-induced prolactin-secreting tumors. Neuroendocrinology 1988; 48:569-76. [PMID: 2469030 DOI: 10.1159/000125064] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The response of folliculo-stellate (FS) cells of the anterior pituitary to estrogen has been studied in two strains of rat which differ in estrogen responsiveness. Fischer 344 (F344) rats are highly estrogen-responsive in comparison to Sprague-Dawley (S-D) rats. Ovariectomized adults were implanted with silastic capsules containing 17 beta-estradiol benzoate. Control and experimental animals were sacrificed 10 and 20 days after implantation of the silastic capsules. Most FS cells of F344 rats revealed dramatic changes, i.e. activation as phagocytes, after 10 and 20 days of estrogen treatment. These activated FS cells separated themselves from adjacent parenchymal cells and frequently contained phagosomes which included portions of granulated cells, mostly somatotrophs and lactotrophs. They also contained a variety of lysosomal dense bodies and dilated cisterns of endoplasmic reticulum. Endfeet processes abutting the parenchymal basal lamina contained large aggregates of dumbbell-shaped granules and tubulo-vesicles. Subjacent to the endfeet processes the basal lamina was often discontinuous, and profiles suggesting uptake of fragments of the basal lamina by FS cells were evident. Most FS cells of estrogen-treated S-D rats either were identical to those of controls or were only minimaly modified. However, a few activated FS cells were present and these contained a variety of lysosomal dense bodies and phagosomes, as well as lipid inclusions and dilated endoplasmic reticulum. Endfeet projections at the parenchymal basal lamina contained very few dumbbell-shaped granules or tubulo-vesicles, and the basal lamina was intact.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J Schechter
- Department of Anatomy and Cell Biology, University of Southern California School of Medicine, Los Angeles
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