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Stewart DA. Words and things: paradigms lost or never found. AJNR Am J Neuroradiol 1994; 15:1565-6; discussion 1566-8. [PMID: 7985578 PMCID: PMC8334410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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77
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Abstract
Metastatic stromal cell tumors of the testis are largely refractory to chemotherapy. We report a case of a young man with widely metastatic testicular stromal cell tumor who achieved complete clinical remission following chemotherapy with etoposide, ifosfamide, cisplatin, and bleomycin.
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78
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Roskams AJ, Friedman V, Wood CM, Walker L, Owens GA, Stewart DA, Altus MS, Danner DB, Liu XT, McClung JK. Cell cycle activity and expression of prohibitin mRNA. J Cell Physiol 1993; 157:289-95. [PMID: 8227162 DOI: 10.1002/jcp.1041570211] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Prohibitin, a novel intracellular antiproliferative protein, blocks entry into the S phase of the cell division cycle when its mRNA is microinjected into normal fibroblasts or HeLa cells. To learn more about the interaction between prohibitin and the cell cycle, we studied the effect of microinjecting prohibitin mRNA at different points during the transition from G0 to S phase and analyzed prohibitin mRNA and protein levels in different parts of the cell cycle. The antiproliferative activity of microinjected prohibitin mRNA is high in G0/G1 and falls as cells approach S phase. Prohibitin mRNA and protein levels are high in G1, fall with S phase, rise again in G2, and fall in M. Together, these findings suggest that endogenous prohibitin contributes to the control of the G1 to S transition in cycling cells in a complex manner, which involves both a transcriptional and posttranslational mechanism.
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79
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Stewart DA. Bi-Bi to MCE? AMERICAN ANNALS OF THE DEAF 1993; 138:331-337. [PMID: 8273703 DOI: 10.1353/aad.2012.0384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
In the past few years, we have witnessed the introduction of a bilingual-bicultural approach and an increasing skepticism of the value of manually coded English in the education of deaf children. The thrust of bilingual-bicultural programs is emphasis on using American Sign Language as the primary language of instruction. However, merely advocating something (i.e., the use of American Sign Language) in no way guarantees its successful implementation. This paper reviews the research on past usage of manually coded English in the classroom for clues as to some of the concerns that American Sign Language might face in its implementation.
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80
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Stewart DA, Grunstein RR, Berthon-Jones M, Handelsman DJ, Sullivan CE. Androgen blockade does not affect sleep-disordered breathing or chemosensitivity in men with obstructive sleep apnea. THE AMERICAN REVIEW OF RESPIRATORY DISEASE 1992; 146:1389-93. [PMID: 1456553 DOI: 10.1164/ajrccm/146.6.1389] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
As sleep apnea is more prevalent in men and testosterone has known effects on sleep apnea and chemosensitivity, reduction of androgen activity may influence sleep-disordered breathing and respiratory control. We studied the effect of 1 wk of treatment with flutamide, a nonsteroidal antiandrogen, on sleep, respiration, and ventilatory control in eight men with sleep apnea. Results on flutamide were compared with two baseline studies performed before and after the drug treatment period. Although effective androgen blockade was achieved as evidenced by increased hormone levels, flutamide had no effect on sleep architecture or chemoresponsiveness to hypoxia and hypercapnia. There was a trend towards a reduction in respiratory disturbance index in both NREM and REM sleep (41 +/- 4 baseline versus 34 +/- 3 flutamide, p = 0.09 NREM; 53 +/- 4 baseline versus 48 +/- 3 flutamide, p = 0.16 REM), but this was not significant. Our results indicate that androgen blockade had no clinically significant effect on sleep, sleep-disordered breathing, or chemosensitivity in patients with moderate to severe sleep apnea. More specific blockers such as gonadotrophin-releasing hormone analogs may have more clinical effect or, alternatively, androgen blockade may be more beneficial in patients with milder sleep apnea.
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81
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Stewart DA, Taylor J, Ghosh S, Macphee GJ, Abdullah I, McLenachan JM, Stott DJ. Terodiline causes polymorphic ventricular tachycardia due to reduced heart rate and prolongation of QT interval. Eur J Clin Pharmacol 1992; 42:577-80. [PMID: 1623896 DOI: 10.1007/bf00265918] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Recent reports have suggested an association between terodiline hydrochloride and cardiac arrhythmias. We report 4 patients presenting over a six month period who developed polymorphic ventricular tachycardia (polymorphic VT) while receiving treatment with this agent. In each case there was prolongation of QT interval on electrocardiogram (ECG). Two patients had hypokalaemia associated with diuretic therapy. In the 3 cases in which follow-up ECG was available, QT interval returned to normal after discontinuation of terodiline. In order to define the effects of terodiline on corrected QT interval (QTc) and heart rate in the elderly, a prospective study was performed in 8 elderly in-patients treated with terodiline for urinary incontinence. After 7 days treatment with terodiline 12.5 mg twice daily, there was a significant increase in QT by a mean of 29 ms, QTc by 15 ms and a decrease in resting heart rate by a mean of 6.7 beats.min-1. Terodiline increases QTc and reduces resting heart rate in elderly patients. Both these effects may be associated with polymorphic VT, a potentially life threatening arrhythmia. This drug should be avoided in patients with other known risk factors for polymorphic VT, particularly hypokalaemia and cardiac disease.
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82
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Stewart DA, Burns JM, Beard K, Dall JL, Lennox IM, Roberts MA, Macfarlane GJ. The roles of general and geriatric medicine in the provision of acute medical care for elderly patients. HEALTH BULLETIN 1992; 50:259-66. [PMID: 1506196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
To determine whether there are differences between elderly patients admitted acutely to general medicine and those admitted to geriatric medical wards, and whether the patients are appropriately referred, a prospective survey of 426 consecutive patients aged 65 years or over admitted acutely to general medical and geriatric wards over a three month period was performed. A total of 286 patients were admitted to general medicine (GM) and 140 to the geriatric unit (GER). GER patients were older (81.0 v. 75.8 years) and had greater pre-morbid functional impairment and incontinence. Fewer GER patients presented with readily apparent organ specific diagnoses (56% v. 94%). Median length of stay was longer in GER patients (23 days v. 9 days). Variables independently predictive of GER admission were increasing age, increasing duration of illness, poor pre-morbid functional status and prior reliance on a carer. Length of stay was not associated with unit of admission allowing for the variables described above. GER patients are a different population. They have more chronic illness and functional impairment, and are more likely to require multidisciplinary assessment and rehabilitation in addition to treatment of presenting illness. Elderly patients are appropriately referred by General Practitioners (GPs) without a formal admissions policy.
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83
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Stewart DA, Stein A, Forrest GC, Clark DM. Psychosocial adjustment in siblings of children with chronic life-threatening illness: a research note. J Child Psychol Psychiatry 1992; 33:779-84. [PMID: 1601948 DOI: 10.1111/j.1469-7610.1992.tb00913.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The psychosocial functioning of 10 siblings of children with chronic life-threatening illness and their parents was compared with 10 healthy matched controls. The main differences found were in family relationships, with the index siblings expressing more negative emotion in relation to their fathers than controls, index mothers being less involved in social activities and index fathers being less involved with the extended family. No significant differences were found in any of the measures of depression, anxiety and self concept. Index siblings expressed a number of other concerns such as a fear of the break up of their family after the sick child died. The need for increased awareness of the welfare of healthy siblings as well as closer involvement of the fathers is discussed.
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84
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Wleklinski M, Giardina M, Stewart DA. Curricula non medica. AJNR Am J Neuroradiol 1992; 13:1495-9. [PMID: 1414849 PMCID: PMC8335220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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85
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McKillop GM, Stewart DA, Burns JM, Ballantyne D. Doppler echocardiography in elderly patients with ejection systolic murmurs. Postgrad Med J 1991; 67:1059-61. [PMID: 1800964 PMCID: PMC2399202 DOI: 10.1136/pgmj.67.794.1059] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Thirty-nine elderly patients, mean age 77 years (range 65 to 96), with ejection systolic murmurs were studied to evaluate the functional significance of these murmurs. Subjects were evaluated clinically, by 2-D echocardiography, and by a full Doppler echocardiography study. Good quality Doppler signals were obtained in 35 subjects. Mitral regurgitation was found to be the only significant valvular lesion in 6 patients (17%). Doppler gradients in systole across the aortic valve were less than 30 mmHg in 28 subjects (80%) and were considered not significant. Gradients of greater than 30 mmHg representing significant aortic stenosis were found in 7 subjects (20%). The clinical sensitivity in detecting significant aortic stenosis was 44% and specificity was 81%. Doppler evidence of significant aortic stenosis was found in a substantial proportion of these elderly subjects. Neither clinical assessment nor 2-D echocardiography can be relied on to exclude this condition.
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86
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White JJ, Ledbetter DH, Eddy RL, Shows TB, Stewart DA, Nuell MJ, Friedman V, Wood CM, Owens GA, McClung JK. Assignment of the human prohibitin gene (PHB) to chromosome 17 and identification of a DNA polymorphism. Genomics 1991; 11:228-30. [PMID: 1684951 DOI: 10.1016/0888-7543(91)90126-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Prohibition is a recently identified antiproliferative protein whose exact role in the cell is under investigation. To determine the human chromosomal location of the prohibition gene (PHB) and whether this site corresponds to that of any suspected tumor suppressor gene, we have analyzed DNA from three sources by hybridization analysis: mouse--human hybrid cell lines, hybrid cell lines containing portions of human chromosomes, and human metaphase chromosomes in situ. All three techniques confirm a location in the region 17q21-q22, a region genetically linked to early-onset human breast cancer. Further analysis will be required to establish the significance of this relationship; Southern hybridizations show a polymorphic EcoRI site that may be useful for this purpose.
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87
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Donovan DM, Remington MP, Stewart DA, Crouse JC, Miles DJ, Pearson NJ. Functional analysis of a duplicated linked pair of ribosomal protein genes in Saccharomyces cerevisiae. Mol Cell Biol 1990; 10:6097-100. [PMID: 2233736 PMCID: PMC361414 DOI: 10.1128/mcb.10.11.6097-6100.1990] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Ribosomal protein genes RP28 and S16A (RP55) are closely linked. Another set of this pair of genes exists in the genome (copy 2), genetically unlinked to copy 1. By using gene replacement techniques, we have shown that RP28 from copy 1 is required for vegetative growth and that the cells need S16A from copy 2 to achieve maximum growth rate.
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88
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Stewart DA, Blackman MR, Kowatch MA, Danner DB, Roth GS. Discordant effects of aging on prolactin and luteinizing hormone-beta messenger ribonucleic acid levels in the female rat. Endocrinology 1990; 126:773-8. [PMID: 2298170 DOI: 10.1210/endo-126-2-773] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
To examine the molecular genetic basis for the age-related increase in PRL secretion and decrease in LH production in the rat, we measured steady state levels of PRL and LH beta mRNA in pituitary homogenates and cell lysates from monolayer adenohypophyseal cultures. These mRNA levels were compared with the corresponding levels of immunoreactive PRL and LH in sera and culture media. Paired groups (n = 4-10/group) of intact and 4-week ovariectomized mature (6-7 months old) and old (23-25 months old) female Wistar rats were studied. Serum PRL levels were 550% higher in intact old vs. mature rats (P less than 0.001), whereas the corresponding pituitary homogenate levels of PRL mRNA were similar (P greater than 0.4). Medium PRL concentrations were 230% greater (P less than 0.006) whereas cell lysate concentrations of PRL mRNA were unaltered (P greater than 0.2) in monolayer cultures from intact old vs. mature rats. Serum PRL levels were 650% higher (P less than 0.003) and pituitary homogenate PRL mRNA levels were slightly increased (P less than 0.04) in ovariectomized old vs. mature rats. Neither serum LH values (P greater than 0.07) nor pituitary homogenate LH beta mRNA levels (P greater than 0.1) differed in intact old and mature rats, whereas the corresponding medium concentrations of LH were reduced (P less than 0.001). Ovariectomized old vs. mature rats exhibited reductions in serum (P less than 0.02) and medium (P less than 0.001) LH concentrations, as well as in pituitary homogenate (P less than 0.002) and cell lysate (P less than 0.006) LH beta mRNA levels. Thus, these data revealed coordinate decreases with age in LH beta mRNA and LH secretion, particularly in ovariectomized rats, suggesting an age-related alteration at or before LH beta gene transcription. These findings parallel observations on other genes whose products change with age. In contrast, the observation that the increased secretion of PRL in old rats is accompanied by little or no increase in PRL mRNA is novel and suggests that age-related alterations in PRL gene expression proceed through a posttranscriptional mechanism.
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89
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Stewart DA, McGowan AR, Roberts MA. Multiple gastric carcinoid tumours associated with atrophic gastritis. Scott Med J 1990; 35:19-20. [PMID: 2315684 DOI: 10.1177/003693309003500107] [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: 12/31/2022]
Abstract
A case of multiple gastric carcinoid tumours is described in an elderly man with atrophic gastritis and hypergastrinaemia. This case provides further evidence of an association between hypochlorrhydric states and some gastric endocrine tumours.
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90
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McClung JK, Danner DB, Stewart DA, Smith JR, Schneider EL, Lumpkin CK, Dell'Orco RT, Nuell MJ. Isolation of a cDNA that hybrid selects antiproliferative mRNA from rat liver. Biochem Biophys Res Commun 1989; 164:1316-22. [PMID: 2480116 DOI: 10.1016/0006-291x(89)91813-5] [Citation(s) in RCA: 125] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Studies of chromosome loss in inherited cancers, of fusions between proliferating and quiescent cells, and of microinjection of RNA from quiescent cells into proliferation competent cells have all provided evidence for antiproliferative genes in mammalian cells. In this report, we describe a partial cDNA clone isolated on the basis of its preferential hybridization to RNA from normal versus regenerating rat liver. The corresponding mRNA, enriched by hybrid selection, was microinjected into normal human diploid fibroblasts in cell culture, resulting in a 53% decrease in the fraction of nuclei incorporating tritiated thymidine. This mRNA is 2 kb in size and is expressed in eight tissues examined.
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91
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Beard K, Stewart DA. Assessment of inter-rater reliability. Age Ageing 1989; 18:354. [PMID: 2603843 DOI: 10.1093/ageing/18.5.354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
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92
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McIlroy SG, Goodall EA, McCracken RM, Stewart DA. Rain and windchill as factors in the occurrence of pneumonia in sheep. Vet Rec 1989; 125:79-82. [PMID: 2773236 DOI: 10.1136/vr.125.4.79] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A computerised information retrieval system of abattoir pathology and meteorological data has been used to investigate the effect of prevailing weather conditions on the occurrence of pleurisy and pneumonia in the sheep population of Northern Ireland. Significant correlation coefficients were found between the percentage condemnations due to pleurisy and pneumonia in sheep and rainfall, windspeed, temperature and humidity. The most significant correlation was found with windspeed. The paper describes the calculation of a new meteorological variable, the rain/windchill factor. Very highly significant correlation coefficients were found between the percentage lung condemnations in sheep and the rain/windchill factor prevailing during the same month and both one and two months previously. The paper discusses the practical implications of these findings for sheep production and highlights the desirability of protecting sheep from adverse climatic conditions during the winter months.
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93
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Ledney GD, Stewart DA, Gruber DF, Gelston HM, Exum ED, Sheehy PA. Hematopoietic colony-forming cells from mice after wound trauma. J Surg Res 1985; 38:55-65. [PMID: 3871234 DOI: 10.1016/0022-4804(85)90010-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The changes produced in the pluripotential and progenitor cell compartments of the hind leg bone marrow and spleen of skin-wounded mice were examined over a 2-week post-trauma period. Pluripotent cells (colony-forming unit-spleen, CFU-s) were significantly increased in the spleen and slightly reduced in the leg marrow the first week after trauma. Granulocyte macrophage colony-forming cells (GM-CFC) were significantly increased in the spleen throughout the 2-week period and were increased in the leg marrow during the first post-trauma week. Macrophage colony-forming cells (M-CFC) were significantly decreased in the spleen during the 2-week period and were slightly elevated in the leg marrow during that time. The peripheral blood contained significantly increased concentrations of CFU-s and GM-CFC but not M-CFC. Serum of wounded mice supported growth of GM-CFC but not M-CFC. The growth-promoting factor was extractable by CHCl3 treatment. Serum C-reactive protein concentrations were significantly increased for a 5-day period after wound trauma.
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94
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Stewart DA, Bolin RB, Cheney BA, Hawkins JT, Chapman KW, Tompkins DR. Characteristics of lympho-myelopoietic stem cells isolated from canine peripheral blood. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1984; 172:33-48. [PMID: 6731147 DOI: 10.1007/978-1-4615-9376-8_3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
If hematopoietic stem cells (HSC) could be separated from peripheral blood, it might be possible to harvest these stem cells for potential clinical use. By leukapheresis techniques, we harvested mononuclear cells (MNC) from peripheral blood and then placed these cells over discontinuous stractan gradients of three densities (1.077 gm/ml, 1.071 gm/ml and 1.066 gm/ml). These separated cells were submitted to colony culture to identify colony-forming-unit activity for granulocyte-macrophage (CFU-C) and T-cell lymphocyte (CFU-L) cell lines. The lightest cells (1.066) contained most of the CFU-C and no CFU-L activity. Heavier cells (greater than 1.071) contained CFU-L and very little CFU-C activity. CFU-L colonies could be distinguished from CFU-C by their density and distinct morphological appearance. In addition, the amount of CFU-C could be increased in the animal by increasing the amount of blood processed (from 3.9 +/- .76 CFU-C/10(6) MNC to 6.7 +/- .35 CFU-C/10(6) MNC). This resulted in an increase of CFU-C collected from 7.6 +/- 2.1 CFU-C/10(6) MNC after the first equivalent blood volume to 22.5 +/- 3.4 CFU-C/10(6) MNC after the third equivalent blood volume processed. These results suggest that leukapheresis and gradient density separation may be useful procedures to obtain HSC.
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95
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Stewart DA. The use of sign by deaf children: the opinions of a deaf community. AMERICAN ANNALS OF THE DEAF 1983; 128:878-883. [PMID: 6666742 DOI: 10.1353/aad.2012.0868] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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96
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Bolin RB, Stewart DA, Cheney BA, Chapman KW, Tompkins DR. Granulocyte progenitor cell (CFUC) harvest by continuous apheresis in dogs. Effects of blood volume and lithium on yields. Exp Hematol 1983; 11:226-30. [PMID: 6832247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The ability to harvest large amounts of hematopoietic stem cells from blood would eliminate the more difficult approach of bone marrow harvest. Unfortunately, concentration of stem cells in the blood compartment is less than 1% of their concentration in bone marrow. Attempts to increase harvest of blood stem cells, as assayed by granulocyte progenitor cells (CFUC), have been only partially successful. Our study confirms previous reports that CFUC can be mobilized into the blood compartment in dogs, but this mobilization is rate-limited. Unlike platelets and granulocytes that are effectively harvested during the first blood volume processed by continuous apheresis, effective CFUC harvest begins during the second blood volume (606 +/- 97.9 CFUC/ml), peaks by the third (740 +/- 30 CFUC/ml), and remains constant through five blood volumes processed (700 +/- 272 CFUC/ml). Since blood CFUC concentration falls at the end of five blood volumes processed (40% of initial values), further continuous apheresis would not be effective. Treatment of animals with lithium did not improve CFUC harvest. These results show that apheresis procedures can be developed to a limited extent to increase the harvest of hematopoietic progenitor and stem cells.
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97
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Stewart DA, Ledney GD, Baker WH, Daxon EG, Sheehy PA. Bone marrow transplantation of mice exposed to a modified fission neutron (N/G-30:1) field. Radiat Res 1982; 92:268-79. [PMID: 6761740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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98
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Ledney GD, Stewart DA, Exum ED, Sheehy PA. Skin wound-enhanced survival and myelocytopoiesis in mice after whole-body irradiation. ACTA RADIOLOGICA. ONCOLOGY 1981; 20:29-38. [PMID: 6264741 DOI: 10.3109/02841868109130187] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Skin wounding at 24 h before whole-body 60Co irradiation of mice raised the LD50/30 from 8.09 to 9.71 Gy resulting in a dose reduction factor of 1.2. Concentrations and quantities of myeloproliferative cells were examined at 3, 7, 10, and 14 days after 7 Gy, skin wounding 24 h before 7 Gy and in control non-treated mice. Wounding before irradiation provoked an increase in marrow and splenic clonogenic cells that was earlier and greater than that noted for irradiated mice. Supranormal levels of splenic CFu-s and CFU-c were found in animals wounded before irradiation. M-CFC values were depressed throughout, although greater for combined injured animals than for irradiated mice.
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99
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Ledney GD, Stewart DA, Exum ED. Proliferative responses of lympho-myelopoietic cells of mice after wound trauma. THE JOURNAL OF TRAUMA 1980; 20:141-7. [PMID: 6965506 DOI: 10.1097/00005373-198002000-00007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The hypothesis that wound trauma produces either selective or total organ cell population alterations in the quantities of lympho-myeloproliferative elements in the major hematocytopoietic centers was tested. Mice were subjected to a 4% body surface skin wound on the anterior dorsum; their tissues were assayed 24 hours later for their total cellularity and proliferative potential. In wounded mice, the marrow cellularity was significantly decreased but this did not result in lower stem cell (CFU-s) and progenitor cell (CFU-c and M-CFC) quantities. However, there were significant selective and total population reductions in cells responsive to T and B cell mitogens. Splenic cellularity and stem cell quantities in wounded mice did not differ from control-treated animals. However, there were both selective and total population reductions in splenic CFU-c and M-CFC. Wounding resulted in a greater splenic T cell response to phytohemagglutinin PHA, while the responses to concanavalin-A (CON-A) were similar to controls. The splenic B lymphocyte population was specifically increased. Wounding resulted in a significant thymic hypocellularity. This was mirrored by a selective decrease in M-CFC and a total cell population reduction in response to T cell mitogens.
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100
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Hearse DJ, Stewart DA, Braimbridge MV. The additive protective effects of hypothermia and chemical cardioplegia during ischemic cardiac arrest in the rat. J Thorac Cardiovasc Surg 1980; 79:39-43. [PMID: 7350387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
In a rat heart model of cardiopulmonary bypass and ischemic cardiac arrest the potential additive protective effects of hypothermia and chemical cardioplegia have been investigated. Isolated rat hearts were subjected to a 2 minute period of coronary infusion with a cardioplegic or a noncardioplegic solution immediately before and also at the midpoint of a 2 hour period of hypothermic (20 degrees C) ischemic cardiac arrest. In the hypothermia plus cardioplegia group postischemic aortic flow recovered to more than 50% of its preischemic control value, myocardial energy phosphate content returned to near preischemic control levels, and creatine kinase leakage was moderate. By contrast, in the hypothermia alone group (coronary infusion with non cardioplegic solution) the postischemic functional recovery was less than 30% of its preischemic control value, cellular high-energy phosphate content was considerably reduced, and creatine kinase leakage was more than twice that observed in the hypothermia plus cardioplegia group. In addition to illustrating the additive nature and powerful protective properties of hypothermia and cardioplegia these studies serve to illustrate the utility of the isolated rat heart model for the primary assessment of procedures designed to protect the myocardium during ischemic cardiac arrest. The results and conclusions derived from this study were quantitatively and qualitatively similar to those obtained in a parallel study in the dog.
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