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Lee W, Eng C, Fox N, Etienne M. PACE: a model for integrated care of frail older patients. Program of All-inclusive Care for the Elderly. Geriatrics (Basel) 1998; 53:62, 65-6, 69, 73; quiz 74. [PMID: 9634107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The Program of All-inclusive Care for the Elderly (PACE) is a model of care that pools Medicare and Medicaid funds to provide acute and long-term care services for older patients through the use of interdisciplinary teams. Services include physician visits, prescription drugs, rehabilitation services, personal care workers, hospitalization, and nursing home care, if needed. PACE programs may also offer social services intervention, case management, respite care, or extended home care nursing. The PACE site assumes financial responsibility for all services. Now that PACE programs can become permanent providers under Medicare, their number is expected to grow.
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Richmond S, Daniels CP, Fox N, Wright J. The professional perception of orthodontic treatment complexity. Br Dent J 1997; 183:371-5; discussion 375-7. [PMID: 9419944 DOI: 10.1038/sj.bdj.4809513] [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: 02/05/2023]
Abstract
OBJECTIVE To assess the current professional concept of orthodontic treatment complexity. DESIGN Cross sectional survey of practitioners' views towards recently completed orthodontic treatments. SETTING Specialist and non-specialist practitioners in General Dental Services in North Western and Mersey regions. The sampling was carried out between 1993-95. SUBJECTS AND METHODS All practitioners undertaking orthodontic treatments in the GDS in the North Western and Mersey regions were invited to participate. Practitioners submitted consecutively started cases for scrutiny by analysis of study models and pre-treatment and post-treatment questionnaires. 280 cases were collected. Data were analysed using multiple linear regression. MAIN OUTCOME MEASURES The occlusal changes were assessed using the Index of Orthodontic Treatment Need and the Peer Assessment Rating. Self administered questionnaires employed 5-point Likert type scales to record practitioners' and patients' opinions. RESULTS It appears that the concept of complexity is related to the occlusal changes which occur during orthodontic treatment. Attempts to define treatment complexity identifies factors which are of questionable validity and could be easily manipulated in practice setting. CONCLUSIONS The present concepts of treatment complexity appear to be somewhat flawed. There is no occlusal index of complexity which is particularly satisfactory but as a crude interim measure 3 grades of complexity are proposed based on the PAR index.
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Abstract
BACKGROUND Statistical power is a measure of the extent to which a study is capable of discerning differences or associations which exist within the population under investigation, and is of critical importance whenever a hypothesis is tested by statistics. Conventionally, studies should reach a power level of 0.8, such that four times out of five a false null hypothesis will be rejected by a study. Statistical power may most easily be increased by increasing sample size. OBJECTIVE We aimed to assess the level of statistical power of general practice research. METHODS A total of 1422 statistical tests in 85 quantitative original papers in the British Journal of General Practice were analysed for statistical power. RESULTS The median power of tests analysed was 0.71, representing a slightly greater than two-thirds likelihood of rejecting false null hypotheses. Of 85 studies, 37 (44%) attained power of 0.8 or more. Ten studies had power of more than 0.99 suggesting 'over-powering'. Twenty-one of the papers surveyed (25%) had a likelihood of gaining significant results poorer than that obtained by tossing a coin when a null hypothesis is false. CONCLUSION While achieving higher power than studies in similar surveys of other disciplines, the power of general practice research falls short of the 0.8 convention. Adequate power is essential so that effects which exist are not missed. Recommendations are made concerning power calculations prior to the start of research and reporting of results in journal articles.
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Kordower JH, Mufson EJ, Fox N, Martel L, Emerich DF. Cellular delivery of NGF does not alter the expression of beta-amyloid immunoreactivity in young or aged nonhuman primates. Exp Neurol 1997; 145:586-91. [PMID: 9217095 DOI: 10.1006/exnr.1997.6492] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The present study determined whether grafts of nerve growth factor-producing fibroblasts alter the expression of beta-amyloid in young or aged nonhuman primates. Aged monkeys serve as an animal model which normally exhibits beta-amyloid-laden plaques. Three young adult (7-12 years of age) and three aged (24-29 years of age) rhesus monkeys received intraventricular implants of polymer-encapsulated cells that were genetically modified to secrete human recombinant nerve growth factor (NGF). Three young adult and three aged rhesus monkeys received identical treatment except that the grafted cells were not genetically modified and thus differed only by a single gene construct. Five additional aged rhesus monkeys were ungrafted and also served as controls. Three to four weeks posttransplantation, young monkeys did not display beta-amyloid-immunoreactive profiles within any CNS structure regardless of treatment. Qualitative observations revealed that aged monkeys displayed numerous beta-amyloid plaque-like structures within the amygdala and hippocampus as well as limbic and neocortices. The amount of beta-amyloid immunoreactivity (beta-amyloid load) was quantified bilaterally within the temporal neocortex of these animals. The beta-amyloid load within the temporal neocortex of aged monkeys was highly variable but did not differ across treatment groups. These data indicate that chronic short-term administration of NGF does not affect the expression of beta-amyloid in the young or the aged primate brain.
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Eng C, Pedulla J, Eleazer GP, McCann R, Fox N. Program of All-inclusive Care for the Elderly (PACE): an innovative model of integrated geriatric care and financing. J Am Geriatr Soc 1997; 45:223-32. [PMID: 9033525 DOI: 10.1111/j.1532-5415.1997.tb04513.x] [Citation(s) in RCA: 222] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVES The Program of All-inclusive Care for the Elderly (PACE) is a long-term care delivery and financing innovation. A major goal of PACE is prevention of unnecessary use of hospital and nursing home care. SETTING PACE serves enrollees in day centers and clinics, their homes, hospitals and nursing homes. Beginning at On Lok in San Francisco, the PACE model has been successfully replicated across the country. In 1995, PACE was fully operational in 11 cities in nine states. PARTICIPANTS To enroll in PACE, a person must be 55 years of age or older, be certified by the state as eligible for care in a nursing home and live in the program's defined geographical catchment area. PACE participants are ethnically diverse. In 1995, the average PACE enrollee was 80.0 years old and had an average of 7.8 medical conditions and 2.7 dependencies in Activities of Daily Living. A significant number have bladder incontinence (55%). Many enrollees (39%) live alone in the community, and 14% have no means of informal support. INTERVENTION Medicare and Medicaid waivers allow delivery of services beyond the usual Medicare and Medicaid benefits. The PACE service delivery system is comprehensive, uses an interdisciplinary team for care management, and integrates primary and specialty medical care. PACE receives monthly capitation payments from Medicare and Medicaid. Patients ineligible for Medicaid pay privately. RESULTS Outcomes of PACE programs have been positive. There has been steady census growth, good consumer satisfaction, reduction in use of institutional care, controlled utilization of medical services, and cost savings to public and private payers of care, including Medicare and Medicaid. However, starting up a PACE program requires substantial time and capital, and the model has not yet attracted large numbers of older middle income adults. CONCLUSION The growing number of older people in the United States challenges healthcare providers and policy makers alike to provide high quality care in an environment of shrinking resources. The PACE model's comprehensiveness of health and social services, its cost-effective coordinated system of care delivery, and its method of integrated financing have wide applicability and appeal.
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O'Brien K, McComb JL, Fox N, Wright J. Factors influencing the uptake of orthodontic treatment. BRITISH JOURNAL OF ORTHODONTICS 1996; 23:331-4. [PMID: 8985570 DOI: 10.1179/bjo.23.4.331] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The aim of this investigation was to evaluate the factors that influenced the uptake of orthodontic treatment for patients who were referred for orthodontic treatment to two types of orthodontic treatment provider; a fee per item and hospital service. The following data were collected: (i) basic demographic data; (ii) the need for orthodontic treatment as measured by IOTN; and (iii) the outcome of the consultation. The data analysis with logistic regression revealed that the following variables had a predictive effect on the uptake of treatment: (i) the need for orthodontic treatment; and (ii) the patient's gender. Most of the patients that were referred and accepted for treatment had a definite need for orthodontic treatment.
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Broudy VC, Lin NL, Fox N, Taga T, Saito M, Kaushansky K. Thrombopoietin stimulates colony-forming unit-megakaryocyte proliferation and megakaryocyte maturation independently of cytokines that signal through the gp130 receptor subunit. Blood 1996; 88:2026-32. [PMID: 8822921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Thrombopoietin (Tpo), the ligand for the c-Mpl receptor, is a major regulator of megakaryopoiesis. Treatment of mice with Tpo raises the platelet count fourfold within a few days. Conversely, c-mpl knock-out mice have platelet counts that are 15% that of normal. The subunit structure of the c-Mpl receptor is not fully understood. Some cytokines that stimulate megakaryopoiesis (IL-6, IL-11, leukemia inhibitory factor, and oncostatin M) bind to receptors that use gp130 as a signal transduction subunit. For these reasons, we determined whether gp130 function was required for Tpo-induced signal transduction. Murine marrow cells were cultured in semi-solid media in the presence of Tpo or IL-3, with or without a neutralizing anti-gp130 monoclonal antibody (RX187) or a soluble form of c-Mpl receptor (soluble Mpl) that blocks Tpo bioactivity, and the numbers of colony-forming unit-megakaryocyte (CFU-Meg) colonies were counted on day 5. Murine marrow cells were also cultured in suspension under serum-free conditions for 5 days, and megakaryocyte DNA content was measured by flow cytometry, as an index of nuclear maturation. The addition of RX187 did not block Tpo-induced CFU-Meg colony growth nor CFU-Meg nuclear maturation in suspension culture. However, IL-3-induced CFU-Meg colony growth and megakaryocyte nuclear maturation decreased in the presence of RX187. Soluble Mpl completely ablated Tpo-induced CFU-Meg growth, and partially blocked IL-3-stimulated CFU-Meg growth. Thus the effects of Tpo on megakaryopoiesis in vitro do not depend on cytokines that signal through gp130. Furthermore, it is unlikely that gp 130 serves as a beta chain for the c-Mpl receptor, as Tpo signalling is unimpaired in the presence of RX187. In contrast, the effects of IL-3 on CFU-Meg growth are mediated in part through Tpo and through gp130-signalling cytokines.
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Field T, Ironson G, Scafidi F, Nawrocki T, Goncalves A, Burman I, Pickens J, Fox N, Schanberg S, Kuhn C. Massage therapy reduces anxiety and enhances EEG pattern of alertness and math computations. Int J Neurosci 1996; 86:197-205. [PMID: 8884390 DOI: 10.3109/00207459608986710] [Citation(s) in RCA: 101] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Twenty-six adults were given a chair massage and 24 control group adults were asked to relax in the massage chair for 15 minutes, two times per week for five weeks. On the first and last days of the study they were monitored for EEG, before, during and after the sessions. In addition, before and after the sessions they performed math computations, they completed POMS Depression and State Anxiety Scales and they provided a saliva sample for cortisol. At the beginning of the sessions they completed Life Events, Job Stress and Chronic POMS Depression Scales. Group by repeated measures and post hoc analyses revealed the following: 1) frontal delta power increased for both groups, suggesting relaxation; 2) the massage group showed decreased frontal alpha and beta power (suggesting enhanced alertness); while the control group showed increased alpha and beta power; 3) the massage group showed increased speed and accuracy on math computations while the control group did not change; 4) anxiety levels were lower following the massage but not the control sessions, although mood state was less depressed following both the massage and control sessions; 5) salivary cortisol levels were lower following the massage but not the control sessions but only on the first day; and 6) at the end of the 5 week period depression scores were lower for both groups but job stress score were lower only for the massage group.
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O'Brien K, McComb JL, Fox N, Bearn D, Wright J. Do dentists refer orthodontic patients inappropriately? Br Dent J 1996; 181:132-6. [PMID: 8840582 DOI: 10.1038/sj.bdj.4809188] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
One concern to both providers and consumers of orthodontic treatment is the length of new patient consultation waiting lists. A possible reason for the excessive length of these lists could be unnecessary referral of patients. This research project aimed to identify whether inappropriate referrals for new patient orthodontic consultations were a significant problem. The study was carried out in two FHSA areas in the north of England in two stages. The first part of the study involved an evaluation of GDP referral patterns to orthodontic secondary care providers. In the second part, information on the patients referred by the dentists was collected. We concluded that there was a marked variation in referral rates between the dentists and many patients were referred unnecessarily. Importantly, there was no association between dentists' referral rate and the number of inappropriate referrals made. It appears that referral guidelines for orthodontic treatment are necessary and they should be directed at all general dental practitioners.
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Fox N, Song M, Schrementi J, Sharp JD, White DL, Snyder DW, Hartley LW, Carlson DG, Bach NJ, Dillard RD, Draheim SE, Bobbitt JL, Fisher L, Mihelich ED. Transgenic model for the discovery of novel human secretory non-pancreatic phospholipase A2 inhibitors. Eur J Pharmacol 1996; 308:195-203. [PMID: 8840132 DOI: 10.1016/0014-2999(96)00257-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Transgenic mice were created which overexpress human secretory non-pancreatic phospholipase A2 (sPLA2) pansomatically as a potential disease and drug-testing model. The mice were produced using a DNA construct in which the inducible mouse metallothionein gene promoter drives expression of a human sPLA2 minigene. High levels of sPLA2 were detected in several tissues by immunofluorescence localization. Expression in the testes caused hypospermia and male infertility. Circulating catalytically active sPLA2 could be induced to levels observed in patients undergoing a systemic inflammatory response but had no detectable effect on the mice. Therefore, these results suggest that sPLA2 hyperphospholipasemia alone may have only limited pathophysiological consequences. We further show that 3-[3-acetamide-1-benzyl-2-ethylindolyl-5-oxy]propane phosphonic acid LY311727), a potent new inhibitor of phospholipase A2 catalysis developed by our group, dramatically suppresses the circulating enzyme activity in these animals whereas 3-[3-acetamide-1-benzyl-2-propylindolyl-5-oxy]propane phosphonic acid (LY314024), a substantially less potent LY311727 analog, is without effect. These later results thus motivate the further development of this compound as a potential new therapeutic agent and valuable research tool.
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Sitnicka E, Lin N, Priestley GV, Fox N, Broudy VC, Wolf NS, Kaushansky K. The effect of thrombopoietin on the proliferation and differentiation of murine hematopoietic stem cells. Blood 1996; 87:4998-5005. [PMID: 8652812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
In this study, we explored whether thrombopoietin (Tpo) has a direct in vitro effect on the proliferation and differentiation of long-term repopulating hematopoietic stem cells (LTR-HSC). We previously reported a cell separation method that uses the fluorescence-activated cell sorter selection of low Hoescht 33342/low Rhodamine 123 (low Ho/low Rh) fluorescence cell fractions that are highly enriched for LTR-HSC and can reconstitute lethally irradiated recipients with fewer than 20 cells. Low Ho/low Rh cells clone with high proliferative potential in vitro in the presence of stem cell factor (SCF) + interleukin-3 (IL-3) + IL-6 (90% to 100% HPP-CFC). Tpo alone did not induce proliferation of these low Ho/low Rh cells. However, in combination with SCF or IL-3, Tpo had several synergistic effects on cell proliferation. When Tpo was added to single growth factors (either SCF or IL-3 or the combination of both), the time required for the first cell division of low Ho/low Rh cells was significantly shortened and their cloning efficiency increased substantially. Moreover, the subsequent clonal expansion at the early time points of culture was significantly augmented by Tpo. Low Ho/low Rh cells, when assayed in agar directly after sorting, did not form megakaryocyte colonies in any growth condition tested. Several days of culture in the presence of multiple cytokines were required to obtain colony-forming units-megakaryocyte (CFU-Mk). In contrast, more differentiated, low Ho/high Rh cells, previously shown to contain short-term repopulating hematopoietic stem cells (STR-HSC), were able to form megakaryocyte colonies in agar when cultured in Tpo alone directly after sorting. These data establish that Tpo acts directly on primitive hematopoietic stem cells selected using the Ho/Rh method, but this effect is dependent on the presence of pluripotent cytokines. These cells subsequently differentiate into CFU-Mk, which are capable of responding to Tpo alone. Together with the results of previous reports of its effects on erythroid progenitors, these results suggest that the effects of Tpo on hematopoiesis are greater than initially anticipated.
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Fox N, Harvey RJ, Rossor MN. Protein folding, nucleation phenomena and delayed neurodegeneration in Alzheimer's disease. Rev Neurosci 1996; 7:21-8. [PMID: 8736676 DOI: 10.1515/revneuro.1996.7.1.21] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
This hypothesis attempts to explain how Alzheimer's disease can be both sporadic and autosomal dominant with catastrophic neurodegeneration occurring after decades of normal function. The production of A beta peptide, the subunit of amyloid plaques, from the ubiquitous amyloid precursor protein is discussed. Conformational changes are argued to be crucial to the formation of these amyloid plaques and to their neurotoxicity. Parallels are drawn with prion disease where similarly a normal cellular protein becomes pathogenic once a conformational change is induced. Post-mitotic neurons in the brain are susceptible to this destructive process which is initiated by nucleation phenomena and is then self propagating. An understanding of the conformational changes involved in plaque formation may open new therapeutic avenues in Alzheimer's disease.
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Jacobs LG, Skidmore EA, Freeman K, Lipschultz D, Fox N. Oral fluconazole compared with bladder irrigation with amphotericin B for treatment of fungal urinary tract infections in elderly patients. Clin Infect Dis 1996; 22:30-5. [PMID: 8824962 DOI: 10.1093/clinids/22.1.30] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Fungal urinary tract infections are increasingly prevalent in the elderly in acute and chronic care settings. This randomized trial compares the efficacy and safety of oral fluconazole with the efficacy and safety of bladder irrigation with amphotericin B for treatment of funguria (> or = 10,000 cfu/mL of urine) in 109 hospitalized elderly patients. A second treatment course was given for persistent funguria. Indwelling bladder catheters were present in 69% of the patients. While Candida albicans was the predominant isolate from catheterized patients, C. albicans, Candida tropicalis, and Torulopsis glabrata were recovered from noncatheterized patients. Two days after completion of treatment, funguria was eradicated in 96% of the patients treated with amphotericin B and 73% of those treated with fluconazole (P < .05). At 1 month after study enrollment, the mortality rate associated with all causes was greater among patients who were treated with amphotericin B bladder irrigation than among those who received oral fluconazole therapy (41% vs. 22%, respectively; P < .05); this finding suggests that local therapy may be associated with poorer survival. The proportion of patients without funguria at 1 month after study enrollment was similar in the two treatment groups (84%, amphotericin B group; 80%, fluconazole group). A few minor and mild adverse events occurred.
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Westermark G, Arora MB, Fox N, Carroll R, Chan SJ, Westermark P, Steiner DF. Amyloid formation in response to beta cell stress occurs in vitro, but not in vivo, in islets of transgenic mice expressing human islet amyloid polypeptide. Mol Med 1995; 1:542-53. [PMID: 8529120 PMCID: PMC2229964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Human, but not mouse, islet amyloid polypeptide (IAPP) is amyloidogenic. Transgenic mice overexpressing human IAPP in the beta cells of the islets of Langerhans should be useful in identifying factors important for the deposition of IAPP as insoluble amyloid fibrils. MATERIALS AND METHODS Transgenic mice expressing human IAPP were examined using several experimental models for the production of persistent hyperglycemia, as well as for the overstimulation and/or inhibition of beta cell secretion. Obesity was induced by aurothioglucose. Persistent hyperglycemia was produced by long-term administration of glucocorticosteroids or by partial pancreatectomy. Inhibition of normal beta cell exocytosis by diazoxide administration, with or without concurrent dexamethasone injections, was carried out to increase crinophagy of secretory granules. The human IAPP gene was also introduced into the ab and ob mouse models for diabetes. Finally, isolated islets cultivated in vitro at high glucose concentration were also examined. RESULTS No amyloid deposits were found in the pancreata of any of the animals, either by light microscopy after Congo red staining or by electron microscopy after immunogold labeling with antibodies specific for human IAPP. Aurothioglucose treatment resulted in increased numbers of granules in the beta cell and the appearance of large lysosomal bodies without amyloid. However, islets from db and ob mice expressing human IAPP cultivated in vitro in the presence of glucocorticosteroid and/or growth hormone, were found to contain extracellular amyloid deposits reacting with antibodies to human IAPP. CONCLUSIONS Oversecretion of human IAPP or increased crinophagy are not sufficient for amyloid formation. This indicates that other factors must influence amyloid deposition; one such factor may be the local clearance of IAPP.
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Kaushansky K, Broudy VC, Lin N, Jorgensen MJ, McCarty J, Fox N, Zucker-Franklin D, Lofton-Day C. Thrombopoietin, the Mp1 ligand, is essential for full megakaryocyte development. Proc Natl Acad Sci U S A 1995; 92:3234-8. [PMID: 7536928 PMCID: PMC42140 DOI: 10.1073/pnas.92.8.3234] [Citation(s) in RCA: 239] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The development of megakaryocytes (MKs) from their marrow precursors is one of the least understood aspects of hematopoiesis. Current models suggest that early-acting MK colony-stimulating factors, such as interleukin (IL) 3 or c-kit ligand, are required for expansion of hematopoietic progenitors into cells capable of responding to late-acting MK potentiators, including IL-6 and IL-11. Recently, the Mp1 ligand, or thrombopoietin (Tpo), has been shown to display both MK colony-stimulating factor and potentiator activities, at potencies far greater than that of other cytokines. In light of these findings, we tested the hypothesis that Tpo is absolutely necessary for MK development. In this report we demonstrate that neutralizing the biological activity of Tpo eliminates MK formation in response to c-kit ligand, IL-6, and IL-11, alone and in combination, but that these reagents only partially reduce MK formation in the presence of combinations of cytokines including IL-3. However, despite the capacity of IL-3 to support the proliferation and initial stages of MK differentiation, elimination of Tpo prevents the full maturation of IL-3-induced MK. These data indicate that two populations of MK progenitors can be identified: one that is responsive to IL-3 but can fully develop only in the presence of Tpo and a second that is dependent on Tpo for both proliferation and differentiation. Thus, our results strongly suggest that Tpo is the primary regulator of MK development and platelet production.
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Fox N. Neurological emergencies. Postgrad Med J 1995. [DOI: 10.1136/pgmj.71.831.62-d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Pivik RT, Broughton RJ, Coppola R, Davidson RJ, Fox N, Nuwer MR. Guidelines for the recording and quantitative analysis of electroencephalographic activity in research contexts. Psychophysiology 1993; 30:547-58. [PMID: 8248447 DOI: 10.1111/j.1469-8986.1993.tb02081.x] [Citation(s) in RCA: 484] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Developments in technologic and analytical procedures applied to the study of brain electrical activity have intensified interest in this modality as a means of examining brain function. The impact of these new developments on traditional methods of acquiring and analyzing electroencephalographic activity requires evaluation. Ultimately, the integration of the old with the new must result in an accepted standardized methodology to be used in these investigations. In this paper, basic procedures and recent developments involved in the recording and analysis of brain electrical activity are discussed and recommendations are made, with emphasis on psychophysiological applications of these procedures.
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Fox N, Schrementi J, Nishi M, Ohagi S, Chan SJ, Heisserman JA, Westermark GT, Leckström A, Westermark P, Steiner DF. Human islet amyloid polypeptide transgenic mice as a model of non-insulin-dependent diabetes mellitus (NIDDM). FEBS Lett 1993; 323:40-4. [PMID: 8495745 DOI: 10.1016/0014-5793(93)81444-5] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
To model islet amyloidogenesis in NIDDM and explore the glucoregulatory role of islet amyloid polypeptide (IAPP), we have created transgenic mice containing a rat insulin-I promoter-human IAPP fusion gene. Expression of human IAPP was localized to the islets of Langerhans, anterior pituitary and brain in transgenic animals; blood IAPP levels were elevated 5-fold while fasting glucose levels remained normal. Amyloid deposits have not been detected in transgenic islets suggesting that other co-existing abnormalities in NIDDM may be required for the formation of islet amyloid. These animals provide a unique model for exploring this hypothesis and other proposed functions of IAPP.
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Cassard-Doulcier AM, Gelly C, Fox N, Schrementi J, Raimbault S, Klaus S, Forest C, Bouillaud F, Ricquier D. Tissue-specific and beta-adrenergic regulation of the mitochondrial uncoupling protein gene: control by cis-acting elements in the 5'-flanking region. Mol Endocrinol 1993; 7:497-506. [PMID: 8388995 DOI: 10.1210/mend.7.4.8388995] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Uncoupling protein (UCP) gene expression is tightly restricted to thermogenic brown adipocytes and is rapidly activated by norepinephrine released after cold exposure. To identify cis-acting regulatory elements controlling this gene, a region encompassing 4.5 kilobases of DNA upstream of the transcription start site was analyzed using hybrid UCP-chloramphenicol acetyltransferase reporter gene constructs. Evidence for the presence of both tissue-specific and beta-adrenergic response elements in this 4.5-kilobase region was obtained by comparing the expression of these reporter genes in transfected brown adipocytes (in vitro differentiated), brown preadipocytes, white adipocytes, and Chinese hamster ovary (CHO) cells and from experiments in transgenic animals. Deletion analyses in transfected cells indicated that the minimal region exhibiting promoter activity and tissue specificity is located between -157 and -57 base pairs (bp). A 211-bp activator element located between -2494 and -2283 bp was necessary for full expression in brown adipocytes. This element also activated expression of the homologous -157-bp promoter and expression of a heterologous promoter in both brown adipocytes and CHO cells. A second region, downstream of the activator and possibly located between positions -400 and -157 bp, inhibited the UCP promoter in CHO cells. In mice transgenic for a chloramphenicol acetyltransferase reporter gene containing these elements, expression was both tissue specific and regulatable by environmental temperature changes. These results indicate that both positive and negative cis-acting elements participate in the regulation of UCP gene expression.
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Steiner DF, Fox N, Smeekens SP, Ohagi S, Westermark G, Chan SJ. New molecular perspectives in islet hormone biosynthesis. Biochem Soc Trans 1993; 21:139-42. [PMID: 8449279 DOI: 10.1042/bst0210139] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Ross SR, Choy L, Graves RA, Fox N, Solevjeva V, Klaus S, Ricquier D, Spiegelman BM. Hibernoma formation in transgenic mice and isolation of a brown adipocyte cell line expressing the uncoupling protein gene. Proc Natl Acad Sci U S A 1992; 89:7561-5. [PMID: 1323843 PMCID: PMC49750 DOI: 10.1073/pnas.89.16.7561] [Citation(s) in RCA: 93] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Transgenic mice were produced containing the adipocyte-specific regulatory region from the adipocyte P2 (aP2) gene linked to the simian virus 40 transforming genes. Most of the transgenic mice developed brown fat tumors (hibernomas) in their interscapular brown adipose tissue. Hibernoma formation was noticeable in some of the mice as early as 1 day after birth and most of the mice developed very large tumors by 1 month of age. All of the tumor tissue expressed the brown fat-specific uncoupling protein (UCP) gene as well as the aP2 gene. Several of the tumors have been used to establish cultured cell lines and at least one of these lines can be induced to differentiate into brown adipocytes. The cultured adipocytes express mRNA for UCP upon stimulation with N6,O2'-dibutyryladenosine 3',5'-cyclic monophosphate, norepinephrine, isoproterenol or D7114, a beta 3 adrenergic agonist. Thus, regulation of the key thermogenic gene UCP can now be studied in an established cell line.
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98
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Abstract
Estimates of the cost of diabetes should take into account the development of complications. Patient records identified from the 1987 National Hospital Discharge Survey were used to evaluate the risk of hospitalization due to late complications. Hospitalization for diabetic nephropathy reached a peak of 6.74/1000 between the ages of 45 and 54 years, compared to 0.14 to 1.80/1000 in controls. Diabetic patients less than or equal to 45 years of age were 46 times more likely to be hospitalized due to neuropathy. The risk of cardiovascular complications is high, with a greater incidence of arterial than venous disorders. Diabetic patients were 22 times more likely to be admitted for skin ulcers/gangrene, 15 times more likely due to peripheral vascular disease, and 10 times due to atherosclerosis. The risk of cerebrovascular accident and heart disease was 6 to 10 times greater in diabetic patients. Seventy-five per cent of diabetic cardiovascular disorders are myocardial infarction or chronic ischaemia. Hospitalization from renal complications occurs at younger ages than in the general population. Ophthalmic complications increase with age. Diabetic complications account for 2% of the total hospital admissions in the US in 1987. The total cost of the treatment of late diabetic complications was estimated at +5091 million (cardiovascular 74%; renal diseases 10%; nephropathy 3.6%; ophthalmic disorders 1.5%; other unspecified diseases 10%).
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99
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Clément M, Fox N, Hindle K, St-Lewis S. Crossroads in health care: the delivery of two in-service training programs. ARCTIC MEDICAL RESEARCH 1991; Suppl:205-6. [PMID: 1365103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/25/2023]
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100
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Knowles BB, Faas S, Juretic A, Fox N, Crooke R, Hanahan D, Solter D, Jewett L. SV40 T antigen transgenic mice: cytotoxic T lymphocytes as a selective force in tumor progression. BASIC LIFE SCIENCES 1991; 57:111-24; discussion 125. [PMID: 1726037 DOI: 10.1007/978-1-4684-5994-4_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
MESH Headings
- Amylases/toxicity
- Animals
- Antigens, Polyomavirus Transforming/genetics
- Antigens, Polyomavirus Transforming/immunology
- Carcinogens/toxicity
- Choroid Plexus Neoplasms/etiology
- Choroid Plexus Neoplasms/genetics
- Choroid Plexus Neoplasms/immunology
- Choroid Plexus Neoplasms/pathology
- H-2 Antigens/biosynthesis
- H-2 Antigens/immunology
- Hyperplasia
- Immunization
- Insulin/toxicity
- Lipoma/etiology
- Lipoma/genetics
- Lipoma/immunology
- Lipoma/pathology
- Mice
- Mice, Transgenic
- Neoplasms, Experimental/etiology
- Neoplasms, Experimental/genetics
- Neoplasms, Experimental/immunology
- Neoplasms, Experimental/pathology
- Pancreatic Neoplasms/etiology
- Pancreatic Neoplasms/genetics
- Pancreatic Neoplasms/immunology
- Pancreatic Neoplasms/pathology
- Rats
- Recombinant Proteins/genetics
- Recombinant Proteins/immunology
- Simian virus 40/immunology
- T-Lymphocytes, Cytotoxic/immunology
- Tumor Cells, Cultured/immunology
- Tumor Cells, Cultured/pathology
- Tumor Virus Infections/immunology
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