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Davis S, Tress B, Barber PA, Darby D, Parsons M, Gerraty R, Yang Q, Donnan G, Desmond P. Echoplanar magnetic resonance imaging in acute stroke. J Clin Neurosci 2000; 7:3-8. [PMID: 10847641 DOI: 10.1054/jocn.1999.0142] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Echoplanar magnetic resonance imaging (EPI) enables rapid, non-invasive imaging and analysis of cerebral pathophysiology in acute stroke. It represents an important clinical advance over computed tomography (CT) and conventional magnetic resonance (MR) scanning. It can rapidly delineate infarcted cerebral tissue and distinguish acute from chronic stroke. In addition, EPI has the potential to quickly determine the presence and degree of potentially viable brain tissue in the ischaemic penumbra. Thrombolysis is thought to reperfuse the penumbra and hence reduce infarct size. The thrombolytic agent tissue plasminogen activator (t-PA) improves outcome in ischaemic stroke when administered within the first 3 hours of onset. However, there is a significant risk of haemorrhage, and the time window for benefit may well exceed 3 hours in some patients. Hence, by facilitating diagnosis of 'at-risk' tissue in the ischaemic penumbra, a major clinical role of EPI may well become the rational selection of patients for acute interventional stroke therapy.
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Pecelunas K, Danforth HD, Schildknecht EG, Davis S. Efficacy Evaluation of Lasalocid Plus Roxarsone Combination Medication with Different Geographic Field Strains of Eimeria acervulina. Avian Dis 2000. [DOI: 10.2307/1592501] [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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453
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Mazolewski PJ, Barber A, Williams S, Simoni J, Davis S, Shires GT. Attenuating tumor necrosis factor alpha does not ameliorate other cytokine and peroxidase products during sepsis. Am J Surg 1999; 178:556-9. [PMID: 10670871 DOI: 10.1016/s0002-9610(99)00216-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Recent trials utilizing single anticytokine agents have shown no consistent survival benefit in improving the outcome of sepsis. Since an entire cascade of mediators contributes to the underlying pathophysiology, it is not surprising that monotherapy has proven unsuccessful. The purpose of this study was to measure the effects of attenuating tumor necrosis factor (TNF)alpha early in sepsis. METHODS Three groups of Sprague-Dawley rats were studied. All animals were infused with live Escherichia coli, with group I and group II rats additionally receiving a matrix metalloproteinase inhibitor. Serum levels of TNFalpha, interleukin (IL)-6, malondialdehyde (MDA), and lipid hydroperoxide (LOOH) were compared. RESULTS TNFalpha showed a significant decrease, yet IL-6, MDA, and LOOH (markers of sepsis) levels remained abnormally elevated. CONCLUSION Despite significantly attenuating TNFalpha, the septic response continued. This supports the concept that in sepsis, monotherapy directed at attenuating a single cytokine cannot overcome the tissue-damaging effects of an entire cascade of mediators.
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Gittelsohn J, McCormick LK, Allen P, Grieser M, Crawford M, Davis S. Inter-ethnic differences in youth tobacco language and cigarette brand preferences. ETHNICITY & HEALTH 1999; 4:285-303. [PMID: 10705565 DOI: 10.1080/13557859998065] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
OBJECTIVE To describe and understand variations in cigarette brand preferences between adolescents from varying ethnic and gender groups around the US. DESIGN A qualitative study where adolescents, both smokers and nonsmokers, were interviewed individually in depth. SETTING Schools and recreation centers in four sites: urban Maryland (Baltimore), urban Texas (Houston), rural Alabama and rural New Mexico. PARTICIPANTS 121 adolescent volunteers 13-19 years of age, representing African American, white, American Indian and Hispanic ethnic groups, from both genders. RESULTS Considerable geographic and ethnic variation exists in terminology used by youth to refer to cigarettes and to their use. Clear patterns in brand preference by ethnic group were found that follow patterns of targeted marketing by ethnicity. White teens preferred Marlboro brand cigarettes, while African-American teens who smoke preferred Newports. Hispanic and American Indian teens were more likely to smoke Marlboro or Camel cigarettes. Hispanic teens were most likely to mention low price as a reason for choosing a particular brand or to state that the brand does not matter. Tobacco advertisements targeting ethnic groups and the use of promotional items to encourage teen smoking were also recognized as factors influencing brand preferences. CONCLUSIONS These findings have implications for the design of intervention programs aimed at curbing teen smoking. When working with teens who already smoke, using youth language to target messages at perceived characteristics of commonly used brands may be more effective and meaningful than talking about cigarette use in general. Another implication of this work is to shed light on what impact an advertising ban would have on teen brand preferences, brand loyalty, and prevalence of smoking.
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Davis S, Jones M, Kisling J, Castile R, Tepper RS. Density dependence of forced expiratory flows in healthy infants and toddlers. J Appl Physiol (1985) 1999; 87:1796-801. [PMID: 10562624 DOI: 10.1152/jappl.1999.87.5.1796] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In older children and adults, density dependence (DD) of forced expiratory flow is present over the majority of the full flow-volume curve. In healthy subjects, DD occurs because the pressure drop from peripheral to central airways is primarily dependent on turbulence and convective acceleration rather than laminar resistance; however, an increase in peripheral resistance reduces DD. We measured DD of forced expiratory flow in 22 healthy infants to evaluate whether infants have low DD. Full forced expiratory maneuvers were obtained while the subjects breathed room air and then a mixture of 80% helium-20% oxygen. Flows at 50 and 75% of expired forced vital capacity (FVC) were measured, and the ratio of helium-oxygen to air flow was calculated (DD at 50 and 75% FVC). The mean (range) of DD at 50 and 75% FVC was 1.37 (1.22-1.54) and 1.23 (1.02-1.65), respectively, values similar to those reported in older children and adults. There were no significant relationships between DD and age. Our results suggest that infants, compared with older children and adults, have similar DD, a finding that suggests that infants do not have a greater ratio of peripheral-to-central airway resistance.
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Tepper RS, Jones M, Davis S, Kisling J, Castile R. Rate constant for forced expiration decreases with lung growth during infancy. Am J Respir Crit Care Med 1999; 160:835-8. [PMID: 10471605 DOI: 10.1164/ajrccm.160.3.9811025] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Airway caliber and lung volume (VL) increase many fold between infancy and adulthood; however, these two components of the lung may not increase proportionately during lung growth and development. We evaluated in infants the rate of emptying during forced expiration from near total lung capacity to residual volume. From the flow-volume curves we calculated (1) a rate constant (k) as the change in flow divided by the change in volume between 50% and 75% of expired forced vital capacity (FVC), and (2) the fraction of the FVC expired in 0.5 s (FEV(0.5)/FVC). Seventeen normal healthy infants were evaluated twice; mean ages (ranges) at first and second tests were 30 (5 to 76) and 58 (28 to 98) wk. Analysis of cross-sectional and longitudinal data indicated that the rate of emptying during forced expiration measured by both parameters was greatest in the youngest infants and decreased during infancy. Our findings are consistent with the concept that younger infants have large airways relative to their VL and that VL increases more rapidly than airway caliber early in life.
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Ball D, Bishop J, Smith J, O'Brien P, Davis S, Ryan G, Olver I, Toner G, Walker Q, Joseph D. A randomised phase III study of accelerated or standard fraction radiotherapy with or without concurrent carboplatin in inoperable non-small cell lung cancer: final report of an Australian multi-centre trial. Radiother Oncol 1999; 52:129-36. [PMID: 10577698 DOI: 10.1016/s0167-8140(99)00093-6] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
PURPOSE To investigate the effects separately and together of (a) shortening overall treatment time and (b) giving concurrent carboplatin in patients having radical radiotherapy for inoperable non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Between April 1989 and May 1995, 204 patients with medically inoperable or technically unresectable NSCLC localised to the primary site and regional lymph nodes were randomised to receive one of four treatments using a 2 x 2 factorial design: standard radiotherapy, 60 Gy in 30 fractions in 6 weeks (R6); accelerated radiotherapy, 60 Gy in 30 fractions in 3 weeks (R3); standard radiotherapy as in R6 with carboplatin 70 mg/m2/day for 5 days during weeks 1 and 5 of radiotherapy (R6C); accelerated radiotherapy as in R3 with carboplatin 70 mg/m2/day for 5 days during week 1 of radiotherapy (R3C). RESULTS The estimated median survival of all randomised patients was 15.7 months and estimated 2-year survival was 31%. The longest survival was seen in patients randomised to R6C (median 20.3 months, 41% surviving at 2 years) but there were no statistically significant differences between treatment arms or treatment factors (carboplatin versus no carboplatin, accelerated versus conventional radiotherapy). Haematological toxicity was significantly greater in patients treated with carboplatin and oesophageal toxicity was significantly greater and more protracted in patients treated with accelerated radiotherapy. CONCLUSIONS This study failed to show a significant survival advantage for any of the treatment arms or factors. Halving overall treatment time resulted in significantly greater oesophageal toxicity with no suggestion of a survival advantage.
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Walker PM, Romaschin AD, Davis S, Piovesan J. Lower limb ischemia: phase 1 results of salvage perfusion. J Surg Res 1999; 84:193-8. [PMID: 10357919 DOI: 10.1006/jsre.1999.5641] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Revascularization of an ischemic lower extremity is associated with high morbidity (20-30%) and perioperative mortality (10-20%) regardless of the mode of intervention, surgical or thrombolytic, considered to be due to polymorphonuclear (PMN) activation and mediator release. In this study, the safety and feasibility of cell-free extracorporeal perfusion of the limb with a solution designed to minimize both local and systemic injury was tested. Methods. Patients with severe limb ischemia (sensory/motor loss, rest pain/gangrene) were studied prospectively by random assignment into the treatment arm (n = 14) or control arm (n = 21). Surgical management consisted of restorative procedure, thrombectomy or embolectomy (n = 21), or reconstruction (n = 14). Reperfusion of the ischemic limb was achieved with hypertonic, hyperoncotic perfusate containing anti-oxidants delivered via the arterial tree (mean volume 1835 +/- 824 ml) with initial venous drainage (mean volume 775 +/- 263 ml) in the restorative group. Means were compared by paired t test. Results. No adverse systemic effects were detected after limb perfusion (electrolytes, coagulation, platelet function, CBC). Rapid lactate wash-out was observed within 30 min of perfusion (preperfusion 3.2 +/- 4.1 mM, 30 min postperfusion 0.7 +/- 0.71 mM, P < 0.01). Blunting of PMN activation was shown by chemiluminescence (CL) analysis (preischemic CL: 0.68 +/- 0.2; 30 min CL: 0.47 +/- 0. 2; P < 0.013). F2-isoprostanes, a marker of free radical-mediated systemic lipid peroxidation, were significantly reduced in patients treated with study perfusion method (70.55 +/- 39.54 versus control 194.38 +/- 25.24, P < 0.005). Mortality with treatment was 0/14 versus 5/21 in the control. Complication frequency: MI 0/14 vs 3/21; renal 0/14 vs 1/21; leg edema 1/14 vs 5/21; amputations 2/14 vs 1/21. Conclusion. Modification of limb perfusion in patients with severe limb ischemia, using our simple and rapid (15-20 min) method provides beneficial systemic effects.
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Davis S, Gerraty R. Heparin in acute ischaemic stroke. Med J Aust 1999; 170:566-8. [PMID: 10397055 DOI: 10.5694/j.1326-5377.1999.tb127893.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Davis S. Injection drug use and HIV infection among the seriously mentally ill: a report from Vancouver. CANADIAN JOURNAL OF COMMUNITY MENTAL HEALTH = REVUE CANADIENNE DE SANTE MENTALE COMMUNAUTAIRE 1999; 17:121-7. [PMID: 10351170 DOI: 10.7870/cjcmh-1998-0007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A recently reported outbreak of HIV among injection drug users in Vancouver determined that, in early 1997, 23% of this population was HIV-positive, and that HIV-negative injection drug users were becoming positive at the rate of 18.6% per year, the highest rate reported in North America. One significant factor behind the outbreak is the high prevalence of injection cocaine use among drug addicts in Vancouver. Cocaine, because it has a short "high," creates a need for more frequent injections and therefore increases the likelihood of needle sharing and HIV transmission. The mentally ill in Vancouver are particularly at risk for HIV infection because of their vulnerability to substance misuse and because large numbers of them reside in the main drug-using neighborhood. The provincial and federal governments have made $4,700,000 available to respond to this public health emergency, to be spent on the expansion of community services, including a number of needle-exchange sites. Accessing these and other health care services continues to be a challenge for injection drug users who also suffer from serious mental illnesses; for these persons an assertive case management model may be the most effective way of maintaining continuity of care.
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461
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Simpson E, Rubin G, Clyne C, Robertson K, O'Donnell L, Davis S, Jones M. Local estrogen biosynthesis in males and females. Endocr Relat Cancer 1999; 6:131-7. [PMID: 10731101 DOI: 10.1677/erc.0.0060131] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
It is now apparent that in men and in postmenopausal women, estrogens have important physiological and pathophysiological roles. However, importantly, these actions are at a local level, namely paracrine, autocrine, and even 'intracrine' rather than endocrine in the classical sense. Thus for example local estrogen biosynthesis in the bones of men plays a hitherto unsuspected role in the maintenance of bone mineralization and in epiphyseal fusion; and in the testes, estrogen is essential for male germ cell development. On the other hand, in postmenopausal women, the mesenchymal cells of the breast are the major source of estrogen responsible for breast cancer development. This realization points to the importance of circulating C19 precursors in the maintenance of adequate estrogen biosynthesis in extragonadal sites and suggests the possibility of new therapies to block estrogen synthesis in a tissue-specific fashion.
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462
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Anwer K, Earle KA, Shi M, Wang J, Mumper RJ, Proctor B, Jansa K, Ledebur HC, Davis S, Eaglstein W, Rolland AP. Synergistic effect of formulated plasmid and needle-free injection for genetic vaccines. Pharm Res 1999; 16:889-95. [PMID: 10397610 DOI: 10.1023/a:1018834305079] [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: 11/12/2022]
Abstract
PURPOSE A plasmid-based gene expression system was complexed with protective, interactive, and non-condensing (PINC) polymer system and administered with Medi-Jector, a needle-free injection device (NFID), to achieve high and sustained levels of antigen-specific antibodies in blood circulation. METHODS Human growth hormone (hGH) or bacterial beta-galactosidase gene expression plasmids driven by a cytomegalovirus (CMV) promoter were formulated in saline or complexed with a PINC polymer, polyvinylpyrrolidone (PVP), and intramuscularly or subcutaneously administered into dogs and pigs using a 22-gauge needle or a NFID. The hGH-specific IgG titers in serum were measured by an ELISA. Beta-galactosidase expression was measured in injected muscles by an enzymatic assay or immunohistochemistry. The effect of NFID on DNA stability and topology was assessed by gel electrophoresis. RESULTS Intramuscular (i.m.) or subcutaneous (s.c.) injection of a hGH expression plasmid pCMV-hGH (0.05-0.5 mg/kg) in dogs and pigs elicited antigen-specific IgG antibody titers to expressed hGH. With both routes of injection, pDNA delivery by a NFID was superior to pDNA injection by needle. The magnitude of hGH-specific IgG titers with NFID was 15-20-fold higher than needle injection when pDNA was complexed with PVP, and only 3-4-fold higher with pDNA in saline. The transfection efficiency in the injected muscle, as measured by beta-galactosidase expression, following i.m. injection of pCMV-betagalactosidase/PVP, was not significantly different between needle and NFID-injected groups. CONCLUSIONS These data demonstrate that the combination of pDNA/ PVP complexes and a NFID act synergistically to achieve high and sustained levels of antigen-specific IgG response to expressed antigen. This gene delivery approach may offer advantage over needle injection of naked DNA for the development of genetic vaccines.
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Abstract
There is increasing evidence to suggest that many postmenopausal women experience symptoms alleviated by androgen therapy and that such symptoms may be secondary to androgen deficiency. Affected women complain of fatigue, low libido, and diminished well-being, symptoms easily and frequently attributed to psychosocial and environmental factors. When such symptoms occur in the setting of low circulating bioavailable testosterone, testosterone replacement results in significant improvement in symptomatology and, hence, quality of life for the majority of women. Whether the apparent therapeutic effects of testosterone replacement are mediated by testosterone and its metabolite 5alpha- dihydrotestosterone or are a consequence of aromatization to estrogen is not known. Despite the paucity of data regarding its effects, inclusion of testosterone in postmenopausal hormone replacement regimens is not uncommon and is likely to become more widespread with the availability of preparations developed specifically for women. Other novel and even more controversial potential indications for androgen therapy in women are currently being evaluated. These include use in women with premature ovarian failure, premenopausal androgen deficiency symptoms, postmenopausal and glucocorticosteroid-related bone loss, alleviation of wasting syndrome secondary to human immunodeficiency virus infection, and management of premenstrual syndrome. The aim of this commentary is to very briefly review the rationale for the use of testosterone in women, create awareness of some of the therapeutic options available in various countries, and stimulate discussion of this important aspect of women's health.
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464
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Davis S. Hormone replacement therapy. Indications, benefits and risk. AUSTRALIAN FAMILY PHYSICIAN 1999; 28:437-45. [PMID: 10376367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
BACKGROUND The debate surrounding oestrogen replacement in peri and postmenopausal women has been made overly controversial by the dissemination of misinformation and subjective evaluation of available data both by proponents and opponents of such treatment. OBJECTIVE To review the indications, risks and benefits of oestrogen with and without progestin therapy in postmenopausal women. CONCLUSIONS When prescribed judiciously, such that undesirable side effects are avoided, many women well benefit overall from the use of oestrogen in the postmenopausal years. Clearly many of these benefits are long term in addition to providing acute symptomatic relief.
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465
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Davis S. Syndromes of hyperandrogenism in women. AUSTRALIAN FAMILY PHYSICIAN 1999; 28:447-51. [PMID: 10376368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
BACKGROUND Although the actual incidence is not known, hyperandrogenism seems common among Australian women. Most women with syndromes of hyperandrogenism present with symptoms such as acne, hirsutism and androgenic alopecia, or menstrual irregularity. OBJECTIVES The aim of this overview is: to put in perspective the various causes of hyperandrogenism in women, provide a guide to evaluation of affected women; and briefly review current management strategies. DISCUSSION Hyperandrogenism in women is also associated with significant health problems including infertility, insulin resistance, gestational diabetes, type 2 diabetes mellitus and dyslipidaemia which may or may not be linked with obesity.
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467
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Davis S. Another look at Civil War medical care: Atlanta's Confederate hospitals. JOURNAL OF THE MEDICAL ASSOCIATION OF GEORGIA 1999; 88:9-23. [PMID: 10341486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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468
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Snyder P, Anliker J, Cunningham-Sabo L, Dixon LB, Altaha J, Chamberlain A, Davis S, Evans M, Hurley J, Weber JL. The Pathways study: a model for lowering the fat in school meals. Am J Clin Nutr 1999; 69:810S-815S. [PMID: 10195607 PMCID: PMC4878706 DOI: 10.1093/ajcn/69.4.810s] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We describe the development and implementation of the Pathways school food service intervention during the feasibility phase of the Pathways study. The purpose of the intervention was to lower the amount of fat in school meals to 30% of energy to promote obesity prevention in third- through fifth-grade students. The Pathways nutrition staff and the food service intervention staff worked together to develop 5 interrelated components to implement the intervention. These components were nutrient guidelines, 8 skill-building behavioral guidelines, hands-on materials, twice yearly trainings, and monthly visits to the kitchens by the Pathways nutrition staff. The components were developed and implemented over 18 mo in a pilot intervention in 4 schools. The results of an initial process evaluation showed that 3 of the 4 schools had implemented 6 of the 8 behavioral guidelines. In an analysis of 5 d of school menus from 3 control schools, the lunch menus averaged from 34% to 40% of energy from fat; when the menus were analyzed by using the food preparation and serving methods in the behavioral guidelines, they averaged 31% of energy from total fat. This unique approach of 5 interrelated food service intervention components was accepted in the schools and is now being implemented in the full-scale phase of the Pathways study in 40 schools for 5 y.
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Valenzuela DM, Griffiths JA, Rojas J, Aldrich TH, Jones PF, Zhou H, McClain J, Copeland NG, Gilbert DJ, Jenkins NA, Huang T, Papadopoulos N, Maisonpierre PC, Davis S, Yancopoulos GD. Angiopoietins 3 and 4: diverging gene counterparts in mice and humans. Proc Natl Acad Sci U S A 1999; 96:1904-9. [PMID: 10051567 PMCID: PMC26709 DOI: 10.1073/pnas.96.5.1904] [Citation(s) in RCA: 335] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/1998] [Accepted: 12/18/1998] [Indexed: 01/14/2023] Open
Abstract
The angiopoietins have recently joined the members of the vascular endothelial growth factor family as the only known growth factors largely specific for vascular endothelium. The angiopoietins include a naturally occurring agonist, angiopoietin-1, as well as a naturally occurring antagonist, angiopoietin-2, both of which act by means of the Tie2 receptor. We now report our attempts to use homology-based cloning approaches to identify new members of the angiopoietin family. These efforts have led to the identification of two new angiopoietins, angiopoietin-3 in mouse and angiopoietin-4 in human; we have also identified several more distantly related sequences that do not seem to be true angiopoietins, in that they do not bind to the Tie receptors. Although angiopoietin-3 and angiopoietin-4 are strikingly more structurally diverged from each other than are the mouse and human versions of angiopoietin-1 and angiopoietin-2, they appear to represent the mouse and human counterparts of the same gene locus, as revealed in our chromosomal localization studies of all of the angiopoietins in mouse and human. The structural divergence of angiopoietin-3 and angiopoietin-4 appears to underlie diverging functions of these counterparts. Angiopoietin-3 and angiopoietin-4 have very different distributions in their respective species, and angiopoietin-3 appears to act as an antagonist, whereas angiopoietin-4 appears to function as an agonist.
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Abstract
Simple models for the integration of a selectively neutral transgene into a feral population, by stocking of transgenic individuals, are developed. The impact of stocking individuals having multiple unlinked homozygous locations of the transgene is quantified. Initially it is assumed that there is no overlap between successive generations but a more general model for species having discrete overlapping generations is also developed. The primary application for this work is biological control. It is found that the integration of a transgene is considerably quickened by stocked transgenics carrying the transgene at multiple sites.
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Abstract
The importance of the role of an advanced practice nurse in infectious diseases has been heightened by the human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) epidemic. The unique abilities that are part of the expanded role enable the advanced practice nurse to utilize tools learned as a nurse and combine them with advanced clinical skills to be a comprehensive care provider. The clinical management of the patient with HIV is complex and requires up-to-date knowledge regarding the constantly changing science of the virus.
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Saddik D, Frazer C, Robins P, Reed W, Davis S. Gadolinium-enhanced three-dimensional MR portal venography. AJR Am J Roentgenol 1999; 172:413-7. [PMID: 9930794 DOI: 10.2214/ajr.172.2.9930794] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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474
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O'Brien B, Davis S, Erwin-Toth P. G-tube site care: a practical guide. RN 1999; 62:52-6. [PMID: 10086018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Effective care of your patient's gastrostomy site is key to her recovery--even after she's been discharged. Here we'll zero in on the prevention and treatment of skin problems and tube dislodgement, and review which anchoring device best suits your particular patient's needs.
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