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Cox I, Stevens S. Care of ophthalmic surgical instruments. COMMUNITY EYE HEALTH 2000; 13:40-1. [PMID: 17491960 PMCID: PMC1705974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
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77
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Henderson K, Stevens S, Bailey C, Hall G, Stewart J, Wards R. Comparison of the merits of measuring equine chorionic gonadotrophin (eCG) and blood and faecal concentrations of oestrone sulphate for determining the pregnancy status of miniature horses. Reprod Fertil Dev 1999; 10:441-4. [PMID: 10461677 DOI: 10.1071/rd98096] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The relative merits of measuring blood concentrations of equine chorionic gonadotrophin (eCG, previously known as pregnant mare serum gonadotrophin (PMSG)), or oestrone sulphate (OS), or faecal OS concentrations for determining pregnancy status in miniature horses were investigated. Pregnant mares between 40 and 140 days after mating had serum eCG concentrations > 1 I.U. mL-1, with the highest concentrations occurring between days 50 and 120. However, eCG measurements were susceptible to returning a 'false positive' diagnosis of pregnancy. Plasma OS concentrations ranged from 0.1 to 3.6 ng mL-1 in non-pregnant mares, whereas pregnant mares beyond 100 days post-mating all had plasma OS concentrations > 30 ng mL-1. Faecal OS concentrations ranged from 4 to 89 ng g-1 in non-pregnant mares. For faecal samples collected from pregnant mares 150 days or more after mating, 97% of samples had OS concentrations > 85 ng g-1, the value 3 standard deviations above the mean non-pregnant value. None had values below 67 ng g-1, the value 2 standard deviations above the mean non-pregnant value. These results show that measurement of eCG is suitable for determining pregnancy status in miniature mares between 40 and 100 days post-mating. However, mares returning a 'pregnant' diagnosis should undergo a blood OS test 100 or more days after mating to eliminate the possibility of a 'false positive' diagnosis. Measuring blood OS is recommended as the method of choice for determining pregnancy status in miniature mares 100 or more days after mating. Faecal OS measurements provide a non-invasive alternative to blood OS testing from 150 days post-mating. However, the discrimination between 'pregnant' and 'non-pregnant' levels of OS is not as great in faeces as it is in blood.
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78
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Mohla G, Horvath N, Stevens S. Quality of life improvement in a patient with severe atopic dermatitis treated with photopheresis. J Am Acad Dermatol 1999; 40:780-2. [PMID: 10321614 DOI: 10.1016/s0190-9622(99)70167-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Atopic dermatitis is a common skin disease characterized by severely pruritic eczematous patches, papular and lichenified plaques, excoriations, cracks, and erosions. Photopheresis has been shown to ameliorate the signs and symptoms of atopic dermatitis in some patients. We describe successful results with photopheresis for refractory disease in a patient who chronicled his quality of life weekly for more than 15 years before and during extracorporeal photochemotherapy.
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79
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Stevens S, Drouet M, Lauret MG, Loiry M, Sabbah A. [Basophil activation test using flow cytometry in Hymenoptera venom allergy]. ALLERGIE ET IMMUNOLOGIE 1999; 31:11-4. [PMID: 10070594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
The basophil activation test (TAB) clearly shows evidence to Hymenoptera venoms. Comparison of the TAB value with the clinical history allows fixation of a threshold that will anticipate the type of clinical reaction by the TAB value. For the technique of TAB 3 dilutions are used. The basophil activation values produce a threshold for each dilution. For the first dilution the threshold is 50% activation: below this threshold, 70% of patients would have a local or systemic reaction and above this threshold, 70% of patients would have a systemic allergic reaction.
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80
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Seewoodhary R, Stevens S. Transmission and control of infection in ophthalmic practice. COMMUNITY EYE HEALTH 1999; 12:25-8. [PMID: 17491987 PMCID: PMC1705999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
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81
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Scolding N, Franklin R, Stevens S, Heldin CH, Compston A, Newcombe J. Oligodendrocyte progenitors are present in the normal adult human CNS and in the lesions of multiple sclerosis. Brain 1998; 121 ( Pt 12):2221-8. [PMID: 9874475 DOI: 10.1093/brain/121.12.2221] [Citation(s) in RCA: 236] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In multiple sclerosis, partial remyelination is conspicuous in many lesions, but widespread and lasting myelin repair ultimately fails as disability and handicap accumulate. Thus far, the precise identity of the cell responsible for limited spontaneous myelin repair has remained obscure. In the rodent, the proliferative oligodendrocyte progenitor is the most efficient remyelinating cell; this has now been identified in cultures prepared from normal human brain, but has proved difficult to demonstrate in situ. We adapted techniques using antibodies against the human platelet-derived growth factor-alpha receptor to identify oligodendrocyte progenitors in human tissue sections. Small numbers of oligodendrocyte progenitors were found in normal adult human white matter. Progenitors were also demonstrable in acute and chronic lesions from patients dying with multiple sclerosis, but with no evidence of any marked reactive increase in cell numbers. Understanding the biology of the remyelinating cell, and in particular the reason for its apparent failure to repopulate demyelinated lesions, is important for the development of remyelination treatments.
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82
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83
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Deaton R, Murphy R, Garzon M, Franceschetti D, Stevens S. Good encodings for DNA-based solutions to
combinatorial problems. DNA BASED COMPUTERS II 1998. [DOI: 10.1090/dimacs/044/20] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
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84
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Luo Y, Ge H, Stevens S, Xiao H, Roeder RG. Coactivation by OCA-B: definition of critical regions and synergism with general cofactors. Mol Cell Biol 1998; 18:3803-10. [PMID: 9632764 PMCID: PMC108964 DOI: 10.1128/mcb.18.7.3803] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Molecular dissection of the B-cell-specific transcription coactivator OCA-B has revealed distinct regions important, respectively, for recruitment to immunoglobulin promoters through interaction with octamer-bound Oct-1 and for subsequent coactivator function. Further analysis of general coactivator requirements showed that selective removal of PC4 from the essential USA fraction severely impairs Oct-1 and OCA-B function in a cell-free system reconstituted with partially purified factors. Full activity can be restored by the combined action of recombinant PC4 and the PC4-depleted USA fraction, thus suggesting a joint requirement for PC4 and another, USA-derived component(s) for optimal function of Oct-1/OCA-B in the reconstituted system. Indeed, USA-derived PC2 was found to act synergistically with PC4 in reproducing the function of intact USA in the assay system. Consistent with the requirement for PC4 in the reconstituted system, OCA-B was found to interact directly with PC4. Surprisingly, however, removal of PC4 from the unfractionated nuclear extract has no detrimental effect on OCA-B/Oct-1-dependent transcription. These results lead to a general model for the synergistic function of activation domains in Oct-1 and OCA-B (mediated by the combined action of the multiple USA components) and, further, suggest a functional redundancy in general coactivators.
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85
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Casavant D, Haffajee C, Stevens S, Pacetti P. Aborted implantable cardioverter defibrillator shock during facial electrosurgery. Pacing Clin Electrophysiol 1998; 21:1325-6. [PMID: 9633081 DOI: 10.1111/j.1540-8159.1998.tb00198.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A patient with a fourth-generation transvenous implantable cardioverter-defibrillator system nearly received an inappropriate defibrillation discharge while undergoing electrofulguration of keratotic facial skin lesions. The incident was confirmed by analyses of the implantable cardioverter-defibrillator's time/date stamped event log and stored electrogram record. Therapy was withheld by the noncommitted implantable cardioverter-defibrillator as the pulsed electrocautery was not continued beyond the charging period.
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86
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Ong J, Stevens S, Roeder RG, Eckhardt LA. 3' IgH enhancer elements shift synergistic interactions during B cell development. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1998; 160:4896-903. [PMID: 9590237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
IgH gene expression is tightly controlled over the course of B cell development, B cell activation, and the subsequent differentiation of these cells into Ig-secreting plasmacytes. There are several transcriptional enhancers that map within and downstream of the IgH locus, and some of these have been clearly implicated in the developmental regulation of IgH gene assembly and expression. While some of the individual enhancers from this locus have been studied extensively, the functional interactions possible among this group of enhancers have been largely unexplored. In the present study, we have measured the transcriptional activities of combinations of enhancers introduced into B-lineage cell lines at several different developmental stages. We detected a developmental progression in which the 3' enhancers are initially inactive, then become strongly active through synergistic interactions, and finally achieve a strong level of activity with little interdependency. The relative contributions of E mu (the intron enhancer) and of the 3' enhancers also change as a function of developmental stage. We discuss these results in light of parallel studies of developmental changes in transcription factor requirements.
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87
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Fauerbach JA, Lawrence J, Stevens S, Munster A. Work status and attrition from longitudinal studies are influenced by psychiatric disorder. THE JOURNAL OF BURN CARE & REHABILITATION 1998; 19:247-52. [PMID: 9622471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Participants (n=95) were assessed at the time of discharge and at 4 and 12 months after discharge in regard to work status and psychiatric history both before and after the burn injury. Complex psychiatric comorbidity and substance abuse disorders that occurred before the burn injury each significantly raised the risk of unemployment before the burn injury; preburn substance abuse also affected unemployment at 4 months after the burn injury. Trends for higher unemployment rates at 12 months after discharge also were noted among those with a preburn history of complex psychiatric comorbidity and alcohol use, anxiety, or mood disorder. Preburn substance-use disorder raised the risk of attrition from the 12-month study; whereas, those diagnosed at the time of discharge with post-traumatic stress disorder or with two or more current psychiatric disorders after the burn injury dropped out less often. The greater risk for unemployment and attrition observed among subjects with psychiatric disorders before the burn injury suggests the need for routine screening, tracking, and assistance in accessing supportive or rehabilitative services to remove barriers to employment.
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88
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Weeks P, Kothari A, Singh N, Suri S, Stevens S. People and Protected Areas: Towards Participatory Conservation in India. J Wildl Manage 1998. [DOI: 10.2307/3802361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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89
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Purrello M, Di Pietro C, Viola A, Rapisarda A, Stevens S, Guermah M, Tao Y, Bonaiuto C, Arcidiacono A, Messina A, Sichel G, Grzeschik KH, Roeder R. Genomics and transcription analysis of human TFIID. Oncogene 1998; 16:1633-8. [PMID: 9569032 DOI: 10.1038/sj.onc.1201673] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
TFIID, a multisubunit protein comprised of TBP (TATA box-binding protein) and TAF(II)s (TBP-associated factors), has a central role in transcription initiation at class II promoters. TAF(II)s role as mediators of regulatory transcription factors, such as pRb and p53, and their involvement in signal transduction pathways suggest that some may participate in the control of cell proliferation and differentiation: therefore, they could be considered potential protooncogenes or antioncogenes. With the aim of starting to analyse these potential roles, we have determined the genomic position of nine human TAF(II) genes (TAF[II]250, TAF[II]135, TAF[II]100, TAF[II]80, TAF[II]55, TAF[II]43, TAF[II]31, TAF[II]28, TAF[II]20/15) and of two previously unknown sequences related to TAF(II)250 and TAF(II)31, respectively. Except for those encoding TAF(II)250 and TAF(II)31, these genes are present in a single copy and, with the exclusion of those for TAF(II)43 and TAF(II)28 (both at 6p21), are localized in different segments of the genome. Indeed, six of them map to a chromosomal region commonly altered in specific neoplasias, which defines them as candidates for involvement in oncogenesis. Our experiments also demonstrate that TAF(II) transcripts are synthesized ubiquitously, mostly at low levels similar to those of TBP. Interestingly, the amount of the major mRNA species detected by TAF(II)20/15 cDNA is higher, which suggests that the polypeptide it encodes may also perform functions independently of TFIID. TAF(II) isoforms, indicated by additional bands on Northern blots, may play a role in modulation of TFIID function. These data will be useful for analysing variations of TAF(II) mRNA phenotype during cell proliferation, differentiation and development, both normal and pathological.
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90
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Fenaughty AM, Fisher DG, Cagle HH, Stevens S, Baldwin JA, Booth R. Sex partners of Native American drug users. JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES AND HUMAN RETROVIROLOGY : OFFICIAL PUBLICATION OF THE INTERNATIONAL RETROVIROLOGY ASSOCIATION 1998; 17:275-82. [PMID: 9495229 DOI: 10.1097/00042560-199803010-00014] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This study describes patterns of sexual behavior and condom use in a sample of Native American drug-using men and women (N = 114). Data are self-reports of sexual behavior in the last 30 days, including descriptions of the most recent sex partners up to five. These data provided information on 157 sex partner pairs, of which at least one partner was a drug user. Native American women (55%) were more likely than Native American men (23%) to report never using condoms for vaginal and anal sex in the last 30 days. Compared with other ethnic pair combinations, sex partner pairs composed of Native American women and white men (n = 18) were the least likely to use condoms (6% of pairs) and the most likely to report an injection drug user (IDU) sex partner (33% of pairs). These results suggest a potential vector of HIV and other sexually transmitted disease (STD) transmission between white male IDUs and Native American women and highlight the need for further qualitative and quantitative research to examine the factors underlying this pattern of sexual risk behavior.
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91
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Stevens S, Unwin CE, Codde JP. A review of hospital medical record audits: implications for funding and training. AUST HEALTH REV 1997; 21:78-91. [PMID: 10185695 DOI: 10.1071/ah980078] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This paper summarises the findings of coding audits in seven hospitals and one re-audit conducted by the Health Department of Western Australia. The accuracy of the coding in the first audits, as measured by differences in AN-DRG assignment, varied from 83% to 93%. The accuracy of the coding in the re-audited hospital increased by 6% to 94.5%. The major coding problems related to incorrect abstraction of information from the medical record, inaccurate code assignment, non-application of the Australian Coding Standards, or poor documentation. On average, these coding problems resulted in a loss of nearly $400,000 per hospital per year in the surveyed hospitals.
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92
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93
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Helms LM, Felix JP, Bugianesi RM, Garcia ML, Stevens S, Leonard RJ, Knaus HG, Koch R, Wanner SG, Kaczorowski GJ, Slaughter RS. Margatoxin binds to a homomultimer of K(V)1.3 channels in Jurkat cells. Comparison with K(V)1.3 expressed in CHO cells. Biochemistry 1997; 36:3737-44. [PMID: 9132027 DOI: 10.1021/bi962351p] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Voltage-gated potassium (K(V)) channels play key roles in setting the resting potential and in the activation cascade of human peripheral T lymphocytes. Margatoxin (MgTX), a 39-amino acid peptide from Centruroides margaritatus, is a potent inhibitor of lymphocyte K(V) channels. The binding of monoiodotyrosinyl margatoxin ([125I]MgTX) to plasma membranes prepared from either Jurkat cells, a human leukemic T cell line, or CHO cells stably transfected with the Shaker-type voltage-gated K+ channel, K(V)1.3, has been used to investigate the properties of lymphocyte K(V) channels. These data were compared with [125I]MgTX binding to heterotetrameric K(V) channels in rat brain synaptic plasma membranes [Knaus, H. G., et al. (1995) Biochemistry 34, 13627-13634]. The affinity for [125I]MgTX is 100-200 fM in either Jurkat or CHO/K(V)1.3 membranes, and the receptor density is 20-120 fmol/mg in Jurkat membranes or 1000 fmol/mg in CHO/K(V)1.3 membranes. In contrast to rat brain, [125I]MgTX binding to Jurkat and CHO/K(V)1.3 membranes exhibits an absolute requirement for K+, with no potentiation of binding by Na+. K(V)1.3 was the only K(V)1 series channel present in either CHO/K(V)1.3 or Jurkat plasma membranes as determined by immunoprecipitation of [125I]MgTX binding or by Western blot analyses using sequence-specific antibodies prepared against members of the K(V)1 family. The relative potencies of a series of peptidyl K(V) channel inhibitors was essentially the same for inhibition of [125I]MgTX binding to Jurkat, CHO, or rat brain membranes and for blocking 86Rb+ efflux from the CHO/K(V)1.3 cells, except that alpha-dendrotoxin was more potent at blocking binding to rat brain membranes than in the other assays. The characteristics of [125I]MgTX binding, the antibody profiles, and the effects of the peptidyl K(V) inhibitors all indicate that the [125I]MgTX receptor in Jurkat lymphocytes is comprised of a homomultimer of K(V)1.3, unlike the heteromultimeric arrangement of the receptor in rat brain.
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94
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Unwin E, Codde J, Gill L, Stevens S, Nelson T. The WA Hospital Morbidity Data System: an evaluation of its performance and the impact of electronic data transfer. Health Inf Manag 1996; 26:189-92. [PMID: 10166460 DOI: 10.1177/183335839702600407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The paper evaluates the performance of the Hospital Morbidity Data System, maintained by the Health Statistics Branch (HSB) of the Health Department of Western Australia (WA). The time taken to process discharge summaries was compared in the first and second halves of 1995, using the number of weeks taken to process 90% of all discharges and the percentage of records processed within four weeks as indicators of throughput. Both the hospitals and the HSB showed improvements in timeliness during the second half of the year. The paper also examines the impact of a recently introduced electronic data transfer system for WA country public hospitals on the timeliness of morbidity data. The processing time of country hospital records by the HSB was reduced to a similar time as for metropolitan hospitals, but the processing time in the hospitals increased, resulting in little improvement in total processing time.
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95
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Martin TM, Kowalczyk C, Stevens S, Wiens GD, Stenzel-Poore MP, Rittenberg MB. Deletion in HCDR3 rescues T15 antibody mutants from a secretion defect caused by mutations in HCDR2. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1996; 157:4341-6. [PMID: 8906808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We recently described mutants of the murine anti-phosphocholine Ab T15, with changes in heavy chain complementarity determining region 2 (HCDR2) that caused loss of secretion. Surprisingly, the T15 HCDR2 mutations did not alter secretion when placed into the related anti-phosphocholine Ab D16, which differs from T15 only in HCDR3 and light (L) chain. Here, we exploit the differences between these two Abs to assess the basis of the secretion defect. The T15 L chain is not secreted in the absence of heavy (H) chain. In contrast, D16 L chain is secreted in the absence of H chain, as are most L chains. We co-expressed the T15 wild-type (wt) and mutant H chains with the D16 L chain, as well as with another secreted L chain, J558L. The mutant H chains were not secreted when expressed with either heterologous L chain. These results establish that the T15 L chain is not uniquely associated with the defect. The T15 and D16 Abs also differ in HCDR3 length in that D16 lacks four amino acid residues (Ser99, Ser100, Tyr100a, Trp100b) present in T15. We deleted these four residues from T15 wt and mutant H chains. Secretion of T15 wt was unaffected by the deletion, but shortening HCDR3 restored secretion in the HCDR2 mutants regardless of L chain association. Together these data demonstrate that both the HCDR2 and HCDR3 domains contain structural information that may affect the secretion competence of Abs.
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96
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Martin TM, Kowalczyk C, Stevens S, Wiens GD, Stenzel-Poore MP, Rittenberg MB. Deletion in HCDR3 rescues T15 antibody mutants from a secretion defect caused by mutations in HCDR2. THE JOURNAL OF IMMUNOLOGY 1996. [DOI: 10.4049/jimmunol.157.10.4341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
We recently described mutants of the murine anti-phosphocholine Ab T15, with changes in heavy chain complementarity determining region 2 (HCDR2) that caused loss of secretion. Surprisingly, the T15 HCDR2 mutations did not alter secretion when placed into the related anti-phosphocholine Ab D16, which differs from T15 only in HCDR3 and light (L) chain. Here, we exploit the differences between these two Abs to assess the basis of the secretion defect. The T15 L chain is not secreted in the absence of heavy (H) chain. In contrast, D16 L chain is secreted in the absence of H chain, as are most L chains. We co-expressed the T15 wild-type (wt) and mutant H chains with the D16 L chain, as well as with another secreted L chain, J558L. The mutant H chains were not secreted when expressed with either heterologous L chain. These results establish that the T15 L chain is not uniquely associated with the defect. The T15 and D16 Abs also differ in HCDR3 length in that D16 lacks four amino acid residues (Ser99, Ser100, Tyr100a, Trp100b) present in T15. We deleted these four residues from T15 wt and mutant H chains. Secretion of T15 wt was unaffected by the deletion, but shortening HCDR3 restored secretion in the HCDR2 mutants regardless of L chain association. Together these data demonstrate that both the HCDR2 and HCDR3 domains contain structural information that may affect the secretion competence of Abs.
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97
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Stevens S, Ordentlich P, Sen R, Kadesch T. HMG box-activating factors 1 and 2, two HMG box transcription factors that bind the human Ig heavy chain enhancer. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1996; 157:3491-8. [PMID: 8871648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We present the isolation of two cDNAs that encode distinct, yet related, proteins that bind the HE2 region of the human Ig heavy chain (IgH) enhancer. Designated HMG box-activating factors (HAF) 1 and 2, the two proteins are new members of the HMG box family of DNA binding proteins. Both are potent transcription activators when expressed 1) as GAL4 fusions targeted to promoters containing GAL4 operators, or 2) as intact proteins targeted to minimal promoters containing binding sites derived from the IgH enhancer. HAF-1 and HAF-2 mRNAs are apparently expressed in both B cells and non-B cells. However, activity generated by the isolated HE2 region in B cells is dependent on both an intact HAF-1/HAF-2 binding site and at least one additional site that has been reported previously to bind a B cell-restricted protein. Our results suggest a collaborative role for either or both HAF-1 and HAF-2 in establishing the B cell activity of the human IgH enhancer.
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98
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Stevens S, Ordentlich P, Sen R, Kadesch T. HMG box-activating factors 1 and 2, two HMG box transcription factors that bind the human Ig heavy chain enhancer. THE JOURNAL OF IMMUNOLOGY 1996. [DOI: 10.4049/jimmunol.157.8.3491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
We present the isolation of two cDNAs that encode distinct, yet related, proteins that bind the HE2 region of the human Ig heavy chain (IgH) enhancer. Designated HMG box-activating factors (HAF) 1 and 2, the two proteins are new members of the HMG box family of DNA binding proteins. Both are potent transcription activators when expressed 1) as GAL4 fusions targeted to promoters containing GAL4 operators, or 2) as intact proteins targeted to minimal promoters containing binding sites derived from the IgH enhancer. HAF-1 and HAF-2 mRNAs are apparently expressed in both B cells and non-B cells. However, activity generated by the isolated HE2 region in B cells is dependent on both an intact HAF-1/HAF-2 binding site and at least one additional site that has been reported previously to bind a B cell-restricted protein. Our results suggest a collaborative role for either or both HAF-1 and HAF-2 in establishing the B cell activity of the human IgH enhancer.
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99
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Kim U, Qin XF, Gong S, Stevens S, Luo Y, Nussenzweig M, Roeder RG. The B-cell-specific transcription coactivator OCA-B/OBF-1/Bob-1 is essential for normal production of immunoglobulin isotypes. Nature 1996; 383:542-7. [PMID: 8849728 DOI: 10.1038/383542a0] [Citation(s) in RCA: 205] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OCA-B was initially identified as a B-cell-restricted coactivator that functions with octamer binding transcription factors (Oct-1 and Oct-2) to mediate efficient cell type-specific transcription of immunoglobulin promoters in vitro. Subsequent cloning studies led to identification of the coactivator as a single polypeptide, designated either as OCA-B (ref. 3), OBF-1 (ref. 4) or Bob-1 (ref. 5). OCA-B itself does not bind to DNA directly, but interacts with either Oct-1 or Oct-2 to potentiate transcriptional activation. To determine the biological role of OCA-B, we generated OCA-B-deficient mice by gene targeting. Mice lacking OCA-B undergo normal antigen-independent, B-cell differentiation, including appropriate expression of both immunoglobulin genes and other early B-cell-restricted genes. However, antigen-dependent maturation of B cells is greatly affected. The proliferative response to surface IgM crosslinking is impaired, and there is a severe deficiency in the production of secondary immunoglobulin isotypes including IgG1, IgG2a, IgG2b, IgG3, IgA and IgE in OCA-B-deficient B cells. This defect is not due to a failure of the isotype switching process, but rather to reduced levels of transcription from normally switched immunoglobulin heavy-chain loci. In accord with the defective isotype production, germinal centre formation is absent in these mutant mice.
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100
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Nihill P, Lin LY, Salzmann LB, Stevens S. Esthetic overdenture for a patient with possible Seckel syndrome. SPECIAL CARE IN DENTISTRY 1996; 16:210-3. [PMID: 9582723 DOI: 10.1111/j.1754-4505.1996.tb00862.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This is a case report of a 21-year-old with possible Seckel syndrome (bird-headed dwarfism), micrognathia, microdontia, severe bony undercuts, and periodontal disease who sought treatment at a university dental clinic. Treatment included extractions, periodontal therapy, retention of premolars with sealants, and overdentures with resilient soft liners. A limited review of Seckel syndrome literature is included. The modification of existing dental materials and procedures required for successful functional and esthetic results are discussed.
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