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Dutta P, Kwok Y, Herman J, Chin L, Colliver C, St. Clair W, Petit J, Young B, Regine W. Comparison of repeat GK-SRS for refractory or recurrent trigeminal neuralgia: Does dose matter. Int J Radiat Oncol Biol Phys 2004. [DOI: 10.1016/j.ijrobp.2004.07.282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Jennett PA, Scott RE, Affleck Hall L, Hailey D, Ohinmaa A, Anderson C, Thomas R, Young B, Lorenzetti D. Policy implications associated with the socioeconomic and health system impact of telehealth: a case study from Canada. Telemed J E Health 2004; 10:77-83. [PMID: 15104919 DOI: 10.1089/153056204773644616] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
This research was undertaken to inform future telehealth policy directions regarding the socioeconomic impact of telehealth. Fifty-seven sources were identified and analyzed through a comprehensive literature search of electronic databases, the Internet, journals, conference proceedings, as well as personal communication with consultants in the field. The review revealed a focus on certain socioeconomic indicators such as cost, access, and satisfaction. It also identified areas of opportunity for further research and policy analysis and development (e.g., social isolation, life stress, poverty), along with various barriers and challenges to the advancement of telehealth. These included confidentiality, reimbursement, and legal and ethical considerations. To become fully integrated into the health care system, telehealth must be viewed as more than an add-on service. This paper offers 19 general and 20 subject-specific telehealth recommendations, as well as seven policy strategies.
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Jennett PA, Affleck Hall L, Hailey D, Ohinmaa A, Anderson C, Thomas R, Young B, Lorenzetti D, Scott RE. The socio-economic impact of telehealth: a systematic review. J Telemed Telecare 2004; 9:311-20. [PMID: 14680514 DOI: 10.1258/135763303771005207] [Citation(s) in RCA: 202] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We reviewed the socio-economic impact of telehealth, focusing on nine main areas: paediatrics, geriatrics, First Nations (i.e. indigenous peoples), home care, mental health, radiology, renal dialysis, rural/remote health services and rehabilitation. A systematic search led to the identification of 4646 citations or abstracts; from these, 306 sources were analysed. A central finding was that telehealth studies to date have not used socio-economic indicators consistently. However, specific telehealth applications have been shown to offer significant socio-economic benefit, to patients and families, health-care providers and the health-care system. The main benefits identified were: increased access to health services, cost-effectiveness, enhanced educational opportunities, improved health outcomes, better quality of care, better quality of life and enhanced social support. Although the review found a number of areas of socio-economic benefit, there is the continuing problem of limited generalizability.
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Hynes J, McComb T, Young B. Heparin Use in Daily Hemodialysis. Hemodial Int 2004. [DOI: 10.1111/j.1492-7535.2004.0085al.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Riley RD, Burchill SA, Abrams KR, Heney D, Lambert PC, Jones DR, Sutton AJ, Young B, Wailoo AJ, Lewis IJ. A systematic review and evaluation of the use of tumour markers in paediatric oncology: Ewing's sarcoma and neuroblastoma. Health Technol Assess 2003; 7:1-162. [PMID: 12633526 DOI: 10.3310/hta7050] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Parker G, Bhakta P, Lovett CA, Paisley S, Olsen R, Turner D, Young B. A systematic review of the costs and effectiveness of different models of paediatric home care. Health Technol Assess 2003; 6:iii-108. [PMID: 12633528 DOI: 10.3310/hta6350] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Riley RD, Burchill SA, Abrams KR, Heney D, Sutton AJ, Jones DR, Lambert PC, Young B, Wailoo AJ, Lewis IJ. A systematic review of molecular and biological markers in tumours of the Ewing's sarcoma family. Eur J Cancer 2003; 39:19-30. [PMID: 12504654 DOI: 10.1016/s0959-8049(02)00500-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The aims of this study were to perform the first systematic review of molecular and biological tumour markers in tumours of the Ewing's sarcoma family (ESFT), and evaluate the current evidence for their clinical use. A well-defined, reproducible search strategy was used to identify the relevant literature from 1966 to February 2000. Papers were independently assessed for tumour markers used in the screening, diagnosis, prognosis or monitoring of patients with ESFT. Eighty-four papers studying the use of 70 different tumour markers in ESFT's were identified. Low-quality, inconsistent reporting limited meta-analysis to that of prognostic data for 28 markers. Patients with tumours lacking S-100 protein expression have a better overall survival (OS) (hazard ratio (HR)=0.41, 95% confidence interval (CI) 0.19, 0.89) than those with expression; patients with high levels of serum LDH had a worse OS and disease-free survival (DFS) (OS: HR=2.92, CI 2.16, 3.94, DFS: HR=3.38, 95% CI 2.28, 4.99); patients with localised disease and tumours expressing type 1 EWS-FLI1 fusion transcripts had an improved DFS compared with those with other fusion transcript types (HR=0.17, 95% CI 0.079, 0.37). The knowledge base formed should facilitate more informative future research. Improved statistical reporting and large, multicentre prospective studies are advocated.
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Abstract
The understanding of users' views of childhood cancer services has been hampered by several important problems. First, this area has been dominated by the tradition of psycho-oncology, with its overly narrow focus on the psychopathological sequelae of chronic childhood illness. Second, a set of inappropriate and undertheorized assumptions has prevailed about the nature of childhood and children's experiences of illness and children's ability to articulate and report on these. Third, the roles, responsibilities and experiences of parents of children with cancer have been unhelpfully conceptualized and underinvestigated. Finally, there has been a lack of suitable methods for making progress with empirical research in this area. In this paper, we argue that interpretive perspectives and associated methods can offer much to those seeking more insightful and better-informed approaches to the views of users of childhood cancer services. We offer some specific examples of where such approaches have already demonstrated considerable promise, showing, for example, that the parenting role is distinctive and should not be assumed to be interchangeable, theoretically or practically, with that of a carer. We conclude by identifying areas where both empirical research and theoretical development are needed.
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Mao X, Lillington D, Scarisbrick JJ, Mitchell T, Czepulkowski B, Russell-Jones R, Young B, Whittaker SJ. Molecular cytogenetic analysis of cutaneous T-cell lymphomas: identification of common genetic alterations in Sézary syndrome and mycosis fungoides. Br J Dermatol 2002; 147:464-75. [PMID: 12207585 DOI: 10.1046/j.1365-2133.2002.04966.x] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Data on genome-wide surveys for chromosome aberrations in primary cutaneous T-cell lymphoma (CTCL) are limited. OBJECTIVE To investigate genetic aberrations in CTCL. METHODS We analysed 18 cases of Sézary syndrome (SS) and 16 cases of mycosis fungoides (MF) by comparative genomic hybridization (CGH) analysis, and correlated findings with the results of additional conventional cytogenetics, fluorescent in situ hybridization (FISH) and allelotyping studies. RESULTS CGH analysis showed chromosome imbalances (CIs) in 19 of 34 CTCL cases (56%). The mean +/- SD number of CIs per sample was 1.8 +/- 2.4, with losses (1.2 +/- 2.0) slightly more frequent than gains (0.6 +/- 1.0). The most frequent losses involved chromosomes 1p (38%), 17p (21%), 10q/10 (15%) and 19 (15%), with minimal regions of deletion at 1p31p36 and 10q26. The commonly detected chromosomal gains involved 4/4q (18%), 18 (15%) and 17q/17 (12%). Both SS and late stages of MF showed a similar pattern of CIs, but no chromosomal changes were found in three patients with T1 stage MF. Of the 18 SS cases also analysed by cytogenetics, seven showed clonal chromosome abnormalities (39%). Five cases had structural aberrations affecting chromosomes 10 and 17, four demonstrated rearrangement of 1p and three revealed an abnormality of either 6q or 14q consistent with CGH findings. FISH analysis showed chromosome 1p and 17q rearrangements in five of 15 SS cases, and chromosome 10 abnormalities in four SS cases consistent with both the G-banded karyotype and the CGH results. In addition, allelotyping analysis of 33 MF patients using chromosome 1 markers suggested minimal regions of deletion at D1S228 (1p36), D1S2766 (1p22) and D1S397 (1q25). CONCLUSIONS These findings provide a comprehensive assessment of genetic abnormalities in CTCL and a rational approach for further studies.
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Young B, Fitch GE, Dixon-Woods M, Lambert PC, Brooke AM. Parents' accounts of wheeze and asthma related symptoms: a qualitative study. Arch Dis Child 2002; 87:131-4. [PMID: 12138062 PMCID: PMC1719200 DOI: 10.1136/adc.87.2.131] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIMS To examine parents' accounts of how they recognise and judge respiratory symptoms in children, and to investigate their interpretations of respiratory survey questions about wheeze, shortness of breath, and cough. METHODS Qualitative study using semistructured interviews. Data were analysed using the constant comparative method. Nineteen parents of children aged under 6 years were recruited from a cohort of parents who had responded to an earlier respiratory symptom survey and from one general practice. RESULTS Parents judged respiratory symptoms using a range of cues, including changes in the sound of breathing and changes in appearance and behaviour. Experiential resources and contextual factors played an important role in parents' judgements. Interpretations of questions about respiratory symptoms were varied, particularly in relation to the terms "attacks of wheeze" and "shortness of breath". Parents' descriptions of wheeze differed from descriptions of the sound of wheeze used in some survey questionnaires. Parents drew fine distinctions between different "types" of cough and identified a distinct "asthma" cough. CONCLUSIONS Attention needs to be given to the complexity of reporting respiratory symptoms in children and to the importance of contextual factors in parents' judgements. We suggest that questions which require parents to report on children's internal feelings or states be avoided. Consideration should be given to providing parents with explicit direction on what cues to attend to or ignore in reporting symptoms, and to clarifying some questions that are currently used in clinical practice and in surveys.
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Young B. Progress report on integrating skill mix: the radiographer's perspective. Breast Cancer Res 2002. [PMCID: PMC3300465 DOI: 10.1186/bcr491] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
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112
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Young B. Faulty links between profits and R&D spending. Health Aff (Millwood) 2001; 20:310; author reply 311. [PMID: 11816678 DOI: 10.1377/hlthaff.20.6.310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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113
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Dixon-Woods M, Stokes T, Young B, Phelps K, Windridge K, Shukla R. Choosing and using services for sexual health: a qualitative study of women's views. Sex Transm Infect 2001; 77:335-9. [PMID: 11588278 PMCID: PMC1744361 DOI: 10.1136/sti.77.5.335] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
OBJECTIVE To explore women's accounts of choosing and using specialist services for sexual health. METHODS A qualitative study involving semistructured interviews with 37 women screened for Chlamydia trachomatis attending genitourinary medicine and family planning clinics in an East Midlands health authority. RESULTS In making the decision to seek help, women act on a range of specific prompts, including lay ideas about the significance of symptoms; their own behaviour; their partner's symptoms or behaviour; contact tracing; and health promotion. Some women do not seek help specifically in relation to sexual health but are identified as being at risk of sexually transmitted infections (STIs) during routine consultations. Important influences on women's choice of services include the lay referral system, "insider" knowledge of health services, referral by health professionals, and need to have alternatives to general practice care. Women's willingness to access services is mediated by psychosocial factors such as embarrassment. They may use smear tests as a legitimate opportunity to raise questions about sexual health. Women's priorities for services are that their feelings of stigma and embarrassment are managed appropriately; that staff communicate well and are sensitive to their emotions and comfort during tests and procedures; that they are "in control" when obtaining test results; and that confidentiality is preserved. CONCLUSIONS A detailed understanding of both lay people's response to symptoms or behaviour that indicates risk of an STI and their needs when using services should inform interventions aimed at encouraging secondary prevention of STIs.
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Young B, Spoehr H. Ha'i ka mo'olelo ola: new developments in Native Hawaiian health. PACIFIC HEALTH DIALOG 2001; 8:247-8. [PMID: 12180503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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Brown ER, MaWhinney S, Jones RH, Kafadar K, Young B. Improving the fit of bivariate smoothing splines when estimating longitudinal immunological and virological markers in HIV patients with individual antiretroviral treatment strategies. Stat Med 2001; 20:2489-504. [PMID: 11512138 DOI: 10.1002/sim.853] [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: 11/11/2022]
Abstract
CD4+ lymphocyte count and HIV RNA plasma viral load are longitudinally monitored in patients with HIV infection. Because data collection intervals may be unequally spaced and these markers experience high within-patient variability, they may be smoothed before use in subsequent models. Estimation strategies must be able to accommodate the drastic changes in viral load which may occur when an individual's treatment strategy is updated. Because these treatment changes are not regimented, these dynamics cannot be modelled using standard methods. We propose univariate and bivariate cubic smoothing splines to fit CD4+ count and viral load over time. The method is developed using state space equations, and the Kalman filter is used to calculate the log-likelihood. Non-linear optimization is used to obtain the maximum likelihood estimates. A modification of the Kalman filter allows non-informative or diffuse priors at the initial observation. Since treatment changes are expected to alter the shape of the curve, we further extend the Kalman filter to permit greater flexibility in the smoothing spline at these time points. The method produces smoothed estimates of the viral load and CD4+ count curves over time.
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Young B, Platt D, Logue D, Ternent H, Fitzpatrick J. Bovine Staphylococcus aureus mastitis: strain recognition and dynamics of infection. J DAIRY RES 2001; 68:377-88. [PMID: 11694041 DOI: 10.1017/s0022029901004897] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Restriction enzyme fragmentation pattern (REFP) analysis was used to recognise Staphylococcus aureus strain variation in naturally occurring bovine subclinical mastitis. Multiple colony REFP analysis identified eight distinct strains of S. aureus in addition to the original strains A and B that were infused via the intramammary route, indicating that individual quarters of the udder may be colonised simultaneously by more than one strain of S. aureus. Examination of multiple colonies per milk sample may benefit bacterial strain recognition as an epidemiological tool in mastitis investigations. The dynamics of intramammary infection were determined using a novel double crossover experimental challenge. Quarters remained persistently infected for several weeks following challenge in all four cows, irrespective of the challenge strain. This indicated that no alteration of the original subclinical infection, including the possible induction of clearance of the quarters infected with S. aureus, or replacement of the original strain by the infused strain was induced by challenge. The persistent subclinical infection in all four animals supports previous reports on the chronicity of S. aureus intramammary infection in dairy cows.
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Ayton P, Sneddon SF, Palmer DB, Rosewell IR, Owen MJ, Young B, Presley R, Subramanian V. Truncation of the Mll gene in exon 5 by gene targeting leads to early preimplantation lethality of homozygous embryos. Genesis 2001; 30:201-12. [PMID: 11536426 DOI: 10.1002/gene.1066] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The mixed lineage leukemia gene (MLL) was originally identified through its involvement in reciprocal translocations in leukemias. MLL codes for a large multidomain protein and bears homology to the Drosophila developmental control gene trithorax in two small domains in the amino terminal region, the central zinc finger domain and the carboxy SET domain. Like the Drosophila trx, MLL has also been shown to be a positive regulator of Hox gene expression. We have targeted Mll (the murine homologue of MLL) in exon 5 causing expression of three truncated in-frame Mll transcripts. These transcripts retain all or some of the AT hook motifs and the DMT domain. This mutant allele causes early in vivo preimplantation lethality of homozygous embryos prior to the 2-cell stage. Embryos cultured in vitro progress to the 2-cell stage, but further development is arrested. The heterozygotes exhibit mild skeletal defects as well as defects in some neuroectodermal derivatives.
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Stender H, Sage A, Oliveira K, Broomer AJ, Young B, Coull J. Combination of ATP-bioluminescence and PNA probes allows rapid total counts and identification of specific microorganisms in mixed populations. J Microbiol Methods 2001; 46:69-75. [PMID: 11412915 DOI: 10.1016/s0167-7012(01)00256-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We have combined ATP-dependent bioluminescence with a novel chemiluminescent in situ hybridization (CISH) method using peroxidase-labeled peptide nucleic acid (PNA) probes targeting species-specific rRNA sequences to provide total counts and subsequent identification of specific microorganisms. Both methods are applied to the same membrane filter following a short incubation time and both methods provide results in the form of spots of light that are captured by the MicroStar detection system. Each spot of light represents individual micro-colonies detected by either ATP bioluminescence or PNA CISH. This new concept is particularly intended for in process and quality control of non-sterile products to rapidly provide total counts as well as presence/absence of specific indicators and/or pathogens in non-sterile, filterable samples.
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Lichtenstein KA, Ward DJ, Moorman AC, Delaney KM, Young B, Palella FJ, Rhodes PH, Wood KC, Holmberg SD. Clinical assessment of HIV-associated lipodystrophy in an ambulatory population. AIDS 2001; 15:1389-98. [PMID: 11504960 DOI: 10.1097/00002030-200107270-00008] [Citation(s) in RCA: 335] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE To identify clinical factors associated with prevalence of fat atrophy (lipoatrophy) and fat accumulation (lipoaccumulation) in HIV-1 infected patients. DESIGN Evaluation of HIV-1 infected patients seen for routine care between 1 October and 31 December 1998 in the eight HIV Outpatient Study (HOPS) clinics. SETTING Eight clinics specializing in the care of HIV-1 infected patients. PATIENTS A total of 1077 patients were evaluated for signs of fat maldistribution. INTERVENTIONS A standardized set of questions and specific clinical signs were assessed. Demographic, clinical and pharmacological data for each patient were also included in the analysis. MAIN OUTCOME MEASURES Demographic, immunologic, virologic, clinical, laboratory, and drug treatment factors were assessed in stratified and multivariate analyses for their relationship to the presence and severity of fat accumulation and atrophy. RESULTS Independent factors for moderate/severe lipoatrophy for 171 patients were increasing age, any use of stavudine, use of indinavir for longer than 2 years, body mass index (BMI) loss, and measures of duration and severity of HIV disease. Independent risk factors for moderate/severe fat accumulation for 104 patients were increasing age, BMI gain, measures of amount and duration of immune recovery, and duration of antiretroviral therapy (ART). The number of non-drug risk factors substantially increased the likelihood of lipoatrophy. If non-drug risk factors were absent, lipoatrophy was unusual regardless of the duration of drug use. CONCLUSIONS HIV-associated lipodystrophy is associated with several host, disease, and drug factors. While prevalence of lipoatrophy increased with the use of stavudine and indinavir, and lipoaccumulation was associated with duration of ART, other non-drug factors were strongly associated with both fat atrophy and accumulation.
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Kaysen GA, Chertow GM, Adhikarla R, Young B, Ronco C, Levin NW. Inflammation and dietary protein intake exert competing effects on serum albumin and creatinine in hemodialysis patients. Kidney Int 2001; 60:333-40. [PMID: 11422769 DOI: 10.1046/j.1523-1755.2001.00804.x] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Cross-sectional studies have shown an inverse correlation between serum C-reactive protein (CRP) and serum albumin concentration in hemodialysis patients. The net effects of inflammation and dietary protein intake on nutritional markers over time are unknown. METHODS To explore the effects of CRP and normalized protein catabolic rate (nPCR) on serum albumin and creatinine, we analyzed six consecutive months of laboratory data from 364 hemodialysis patients, using a multivariable Mixed model with conservative biases. RESULTS The overall trend over time in serum albumin was slightly positive (0.039 g/dL/month) and in serum creatinine slightly negative (-0.052 mg/dL/month). With increasing CRP, serum albumin declined significantly (-0.124 g/dL/month per unit increase in log CRP, adjusted for age, gender, race, diabetes, and nPCR, P < 0.0001). Serum albumin increased with increasing nPCR (0.021 g/dL/month per 0.1 g/kg/day, P < 0.0001). The effect of CRP on albumin was attenuated in African Americans and at a higher nPCR. Corresponding values for creatinine mirrored those for albumin. With increasing CRP, creatinine declined significantly [-0.142 mg/dL/month per unit increase in log CRP, adjusted for age, gender, race, diabetes (time since initiation of dialysis; vintage), Kt/V, and nPCR, P = 0.002]. Serum creatinine increased with increasing nPCR (0.183 mg/dL/month per g/kg/day, P < 0.0001). CONCLUSIONS Proxies of inflammation and dietary protein intake exert competing effects on serum albumin and creatinine in hemodialysis patients. These data provide a rationale for prospective testing of dietary protein supplementation in hemodialysis patients with biochemical evidence of ongoing inflammation and "malnutrition."
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Young B. Holistics are not 'loonies'. Aust Vet J 2001; 79:461-2. [PMID: 11549042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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Woods N, Craig IP, Dorr G, Young B. Spray drift of pesticides arising from aerial application in cotton. JOURNAL OF ENVIRONMENTAL QUALITY 2001; 30:697-701. [PMID: 11401259 DOI: 10.2134/jeq2001.303697x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This paper presents results from field studies carried out during the 1993-1998 Australian cotton (Gossypium hirsutum L.) seasons to monitor off-target droplet movement of endosulfan (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepin 3-oxide) insecticide applied to a commercial cotton crop. Averaged over a wide range of conditions, off-target deposition 500 m downwind of the field boundary was approximately 2% of the field-applied rate with oil-based applications and 1% with water-based applications. Mean airborne drift values recorded 100 m downwind of a single flight line were a third as much with water-based application compared with oil-based application. Calculations using a Gaussian diffusion model and the U.S. Spray Drift Task Force AgDRIFT model produced downwind drift profiles that compared favorably with experimental data. Both models and data indicate that by adopting large droplet placement (LDP) application methods and incorporating crop buffer distances, spray drift can be effectively managed.
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Abstract
BACKGROUND Quick diagnosis and treatment of cancers is a UK government priority. However, the process of arriving at a diagnosis of childhood cancer has been neglected in comparison with the attention given to cancers in adults. We investigated parents' narratives about the period before their child's diagnosis. METHODS We undertook semistructured interviews with 20 parents whose children (aged 4-18 years) had a confirmed diagnosis of cancer or brain tumour. All interviews were recorded and fully transcribed. Dates of consultations and investigations were noted from children's medical records. Data were analysed by the constant comparison method. FINDINGS The time before diagnosis is very significant for parents and might affect their adaptation and reaction to their child's diagnosis. Parents were first alerted to their child's illness by a range of signs and symptoms, and by behavioural and affective changes. These early symptoms were often vague, non-specific, and common, and some older children were reluctant to disclose symptoms. Ten families' accounts of this period before diagnosis included a dispute with doctors. Disagreements between parents and doctors about the seriousness of children's symptoms and the need for investigations occurred in both primary and secondary care. Some parents felt that doctors discounted their special knowledge of their child. INTERPRETATION Parents' accounts offer valuable insights into their experiences of obtaining a diagnosis of childhood cancer and into possible sources of delays in this complex process. If delays are to be avoided or reduced, attention must be given to the different roles of parents, children, general practitioners, hospital specialists, and type of cancer. Our findings have important implications for policy, practice, and research, and for the management of childhood illnesses.
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Seddigh-Tonekaboni S, Lim WL, Young B, Hou JL, Waters J, Luo KX, Thomas HC, Karayiannis P. Hepatitis B surface antigen variants in vaccinees, blood donors and an interferon-treated patient. J Viral Hepat 2001; 8:154-8. [PMID: 11264736 DOI: 10.1046/j.1365-2893.2001.00275.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Variants of hepatitis B virus (HBV), with amino acid substitutions in the major antigenic "a" determinant of hepatitis B surface antigen (HBsAg), have been described mainly in vaccinated children. In the present study in addition to vaccinated children, we have investigated Chinese blood donors positive for anti-HBc alone, and a patient with continuing liver disease after interferon-induced seroconversion to anti-HBs. Variants were detected in two of four children with break-through infections. One child had a double mutation (P142S and G145R) and the other a G145A substitution. Three of seven anti-HBc positive Chinese blood donors had a T131I substitution, whilst the interferon-treated patient had a treble amino acid substitution (P142S, G145R and N146D). The present results indicate that HBsAg variants may exist in individuals other than vaccinated children.
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Young B. Malthus among the theologians. CLIO MEDICA (AMSTERDAM, NETHERLANDS) 2001; 59:93-113. [PMID: 11027071 DOI: 10.1163/9789004333338_006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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126
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Stender H, Kurtzman C, Hyldig-Nielsen JJ, Sørensen D, Broomer A, Oliveira K, Perry-O'Keefe H, Sage A, Young B, Coull J. Identification of Dekkera bruxellensis (Brettanomyces) from wine by fluorescence in situ hybridization using peptide nucleic acid probes. Appl Environ Microbiol 2001; 67:938-41. [PMID: 11157265 PMCID: PMC92669 DOI: 10.1128/aem.67.2.938-941.2001] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A new fluorescence in situ hybridization method using peptide nucleic acid (PNA) probes for identification of Brettanomyces is described. The test is based on fluorescein-labeled PNA probes targeting a species-specific sequence of the rRNA of Dekkera bruxellensis. The PNA probes were applied to smears of colonies, and results were interpreted by fluorescence microscopy. The results obtained from testing 127 different yeast strains, including 78 Brettanomyces isolates from wine, show that the spoilage organism Brettanomyces belongs to the species D. bruxellensis and that the new method is able to identify Brettanomyces (D. bruxellensis) with 100% sensitivity and 100% specificity.
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Chen C, Edwards K, Young B, Greenberger E. Close relationships between Asian American and European American college students. THE JOURNAL OF SOCIAL PSYCHOLOGY 2001; 141:85-100. [PMID: 11294169 DOI: 10.1080/00224540109600525] [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: 10/20/2022]
Abstract
The authors examined attitudes and behaviors regarding close relationships between European and Asian Americans, with a particular emphasis on 5 major subgroups of Asian Americans (Chinese, Japanese, Korean, Vietnamese, and Filipino Americans). Participants were 218 Asian American college students and 171 European American college students attending a culturally diverse university. The European Americans did not differentiate among the various subgroups of Asian Americans. Their attitudes regarding close relationships were less positive toward Asian Americans than toward Mexican and African Americans, a finding contrary to the prediction of social exchange theory (H. Tajfel, 1975). In contrast to the European Americans' view of homogeneity among Asian Americans, the 5 major subgroups of Asian Americans expressed a distinctive hierarchy of social preference among themselves. Results are discussed in terms of their implications for future research on interethnic relations involving Asian Americans.
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Florman S, Young B, Allmon JC, Diethelm L, Raafat A. Traumatic pneumothorax ex vacuo. THE JOURNAL OF TRAUMA 2001; 50:147-8. [PMID: 11231686 DOI: 10.1097/00005373-200101000-00031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kügler S, Young B, Miller VL, Goldman WE. Monitoring phase-specific gene expression in Histoplasma capsulatum with telomeric GFP fusion plasmids. Cell Microbiol 2000; 2:537-47. [PMID: 11207606 DOI: 10.1046/j.1462-5822.2000.00078.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Dimorphism is an essential feature of Histoplasma capsulatum pathogenesis, and much attention has been focused on characteristics that are unique to the saprophytic mycelial phase or the parasitic yeast phase. Recently, we identified a secreted calcium-binding protein, CBP, that is produced in large amounts by yeast cells but is undetectable in mycelial cultures. In this study, the green fluorescent protein (GFP) was established as a reporter in H. capsulatum to study regulation of CBP1 expression in cultures and in single cells grown under different conditions and inside macrophages. One GFP version that was optimized for human codon usage yielded highly fluorescent Histoplasma yeast cells. By monitoring GFP fluorescence during the transition from mycelia to yeast, we demonstrated that the CBP1 promoter is only fully active after complete morphological conversion to the yeast form, indicating for the first time that CBP1 is developmentally regulated rather than simply temperature regulated. Continuous activity of the CBP1 promoter during infection of macrophages supports the hypothesis that CBP secretion plays an important role for Histoplasma survival within the phagolysosome. Broth cultures of Histoplasma yeasts carrying a CBP-GFP protein fusion construct were able to secrete a full-length fluorescent fusion protein that remained localized within the phagolysosomes of infected macrophages. Additionally, a comparison of two Histoplasma strains carrying the CBP1 promoter fusion construct either epichromosomally or integrated into the chromosome revealed cell-to-cell variation in plasmid copy number due to uneven plasmid partitioning into daughter cells.
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Stender H, Broomer A, Oliveira K, Perry-O'Keefe H, Hyldig-Nielsen JJ, Sage A, Young B, Coull J. Rapid detection, identification, and enumeration of Pseudomonas aeruginosa in bottled water using peptide nucleic acid probes. J Microbiol Methods 2000; 42:245-53. [PMID: 11044568 DOI: 10.1016/s0167-7012(00)00196-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A new chemiluminescent in situ hybridization (CISH) method that provides simultaneous detection, identification, and enumeration of Pseudomonas aeruginosa in bottled water within 1 working day has been developed. Individual micro-colonies of P. aeruginosa were detected directly on membrane filters following 5 h of growth by use of soybean peroxidase-labeled peptide nucleic acid (PNA) probes targeted to a species-specific sequence in P. aeruginosa rRNA. Within each micro-colony, reaction of the peroxidase with a chemiluminescent substrate generated light that was subsequently captured by film or with a digital camera system. Each spot of light represented one micro-colony of P. aeruginosa. Sensitivity and specificity for the identification of P. aeruginosa were 100% as determined by testing 28 P. aeruginosa strains and 17 other bacterial species that included closely related Pseudomonas species. Furthermore, the number of micro-colonies of P. aeruginosa represented by light spots correlated with counts of visible colonies following sustained growth. We conclude that PNA CISH speeds up traditional membrane filtration techniques and adds the specificity of PNA probe technology to generate fast and definitive results.
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Abstract
As part of a longitudinal study of the development of eating behaviour, the naturally occurring meals of 30 12 month old children were videotaped on four occasions, all in their own homes. Their mealtime behaviour was coded using a scheme developed for the analysis of feeding behaviour over the weaning period, and summarised as counts of coded actions. Thirty of these meals were coded independently by a second observer. With one exception, the reliability of the counts was high (r> 0.9). The median duration of the meals was 17 min (range 1-50) and the median number of times the mother directly gave the child food was 42 (0-172). The median number of food refusals by the child was 11 (0-89), and self feeding actions, 12 (0-101). Counts of eating behaviour for the main and sweet courses during the same meal were only modestly correlated. Between subject variance for different behaviour counts comprised 41% to 54% of the total variance. These results show that 1 year old children are relatively variable in their eating behaviour from meal to meal, so measures taken from a single meal will not reliably summarise children's feeding characteristics. Food refusal is a common feature of eating behaviour in normal children at this age.
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Young B, McNaughton N. Common firing patterns of hippocampal cells in a differential reinforcement of low rates of response schedule. J Neurosci 2000; 20:7043-51. [PMID: 10995850 PMCID: PMC6772825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
Lesion studies show that the hippocampus is critically involved in timing behavior, but so far there has been little analysis of how it might encode time. We recorded the activity of 266 CA1 neurons, 51 CA3 neurons, and 219 entorhinal neurons from rats performing on a differential reinforcement of low rates (DRL) 15 sec schedule in which reinforcement was contingent on responses that occurred at least 15 sec after the preceding response. The unit data were analyzed using two different methods. First, each unit was subjected to an ANOVA that examined the effects of the following: (1) the outcome of the previous response (reward or nonreward); (2) the outcome of the response on which the firing of the cell was synchronized; and (3) time. This showed that, for CA1, CA3, and entorhinal cortex, changes in unit activity were related to all aspects of the task, with the firing of >90% of units recorded in each region being related to at least one of the three factors. Second, intercorrelations between the firing profiles of individual units revealed several functional categories of hippocampal neurons but no clear categories of entorhinal neurons. Of the hippocampal categories, the most common profile was an initial increase in unit activity at the beginning of the DRL interval, followed by a gradual decrease throughout the interval. We suggest that this profile reflects temporal decay in circuits that may code details of the previous trial and that could be used to "time" the DRL interval.
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Adamec R, Young B. Neuroplasticity in specific limbic system circuits may mediate specific kindling induced changes in animal affect-implications for understanding anxiety associated with epilepsy. Neurosci Biobehav Rev 2000; 24:705-23. [PMID: 10974353 DOI: 10.1016/s0149-7634(00)00032-4] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In two complementary experiments, we studied the effects of low frequency stimulation (LFS) of the amygdala on behavioral effects of kindling in rats and cats. These studies tested the hypothesis that kindling induced long term potentiation (KLTP) in amygdala circuits underlies interictal behavioral change. Since LFS can depotentiate LTP, it was predicted that LFS should both depotentiate KLTP and reverse behavioral effects of kindling. In cats, the effects of LFS on KLTP of amygdala efferents was studied, and related to behavioral effects. Partial ventral hippocampal kindling in cats and right amygdala kindling in rodents lastingly increased defensive response to rats in cats, and anxiety-like behavior (ALB) in the elevated plus-maze in rats. In addition, partial kindling reduced predatory attack behavior in cats independent of its effects on defensive response. Partial kindling also induced KLTP of amygdala efferent transmission to ventromedial hypothalamus (VMH) and periaqueductal gray (PAG) in left and right hemispheres. Depotentiation of amygdala efferent KLTP by bilateral amygdala LFS selectively reduced KLTP in right amygdala efferents. At the same time, defensive behavior, but not attack behavior, was returned to levels seen prior to partial kindling. Defensiveness returned to post kindling levels between 44 and 76days after LFS. At the same time, LTP was restored in the right Amygdalo-PAG pathway only. These findings suggest that lasting change in affect produced by kindling depends on LTP of right amygdala efferent transmission to PAG, replicating studies of the effects of FG-7142 on brain and behavior in the cat. The findings suggest further that the spectrum of behavioral changes produced by partial kindling are dependent on changes in a variety of neural circuits, and that amygdala efferent transmission changes are responsible for changes in defensive behavior, but not attack behavior. Effects of LFS were not due to damage, as thresholds to evoke amygdala efferent response were unchanged. Other data suggest KLTP and depotentiation in right Amygdalo-PAG may reflect changes in glutamate receptor density/synapse number. Kindling effects on rat ALB persisted for at least 1month. Bilateral but not unilateral amygdala LFS reversed the effects of kindling on risk assessment in the plus maze for at least 3weeks. Bilateral LFS also reversed the effects of kindling on open arm exploration, but effects were shorter lived, appearing at 1day but not 3weeks after kindling and LFS. These findings are consistent with other studies which suggest that amygdala neuroplasticity in separable amygdala circuits mediates lasting changes in open arm avoidance and risk assessment. Taken together, the findings of both studies support the hypothesis that a form of LTP of specific amygdala circuits underlies lasting changes in affect produced by limbic kindling. Clinical implications of these findings are discussed.
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Ostermann ME, Young B, Sibbald WJ, Nicolle MW. Coma mimicking brain death following baclofen overdose. Intensive Care Med 2000; 26:1144-6. [PMID: 11030173 DOI: 10.1007/s001340051330] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Baclofen toxicity can be a cause of profound coma with brainstem dysfunction mimicking brain death, and is mainly a clinical diagnosis. Measuring plasma levels is not always possible and may be misleading. Imaging results are usually normal. Electroencephalography may show a pattern of burst suppression. At present no effective specific therapy is available. However, as demonstrated in our case, the prognosis can be good even in severe cases, provided it is recognized early enough, and appropriate supportive measures are instituted.
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Ritz B, Morgenstern H, Crawford-Brown D, Young B. The effects of internal radiation exposure on cancer mortality in nuclear workers at Rocketdyne/Atomics International. ENVIRONMENTAL HEALTH PERSPECTIVES 2000; 108:743-751. [PMID: 10964795 PMCID: PMC1638302 DOI: 10.1289/ehp.00108743] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We examined the effects of chronic exposure to radionuclides, primarily uranium and mixed-fission products, on cancer mortality in a retrospective cohort study of workers enrolled in the radiation-monitoring program of a nuclear research and development facility. Between 1950 and 1994, 2,297 workers were monitored for internal radiation exposures, and 441 workers died, 134 (30.4%) of them from cancer as the underlying cause. We calculated internal lung-dose estimates based on urinalysis and whole-body and lung counts reported for individual workers. We examined cancer mortality of workers exposed at different cumulative lung-dose levels using complete risk-set analysis for cohort data, adjusting for age, pay type, time since first radiation monitored, and external radiation. In addition, we examined the potential for confounding due to chemical exposures and smoking, explored whether external radiation exposure modifies the effects of internal exposure, and estimated effects after excluding exposures likely to have been unrelated to disease onset. Dose-response relations were observed for death from hemato- and lymphopoietic cancers and from upper aerodigestive tract cancers, adjusting for age, time since first monitored, pay type, and external (gamma) radiation dose. No association was found for other cancers, including cancers of the lung. Despite the small number of exposed deaths from specific cancer types and possible bias due to measurement error and confounding, the positive findings and strong dose-response gradients observed suggest carcinogenic effects of internal radiation to the upper aerodigestive tract and the blood and lymph system in this occupational cohort. However, causal inferences require replication of our results in other populations or confirmation with an extended follow-up of this cohort.
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Jenis LG, An HS, Stein R, Young B. Prospective comparison of the effect of direct current electrical stimulation and pulsed electromagnetic fields on instrumented posterolateral lumbar arthrodesis. JOURNAL OF SPINAL DISORDERS 2000; 13:290-6. [PMID: 10941887 DOI: 10.1097/00002517-200008000-00004] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The purpose of this prospective study was to compare the effect of adjunctive direct current (DC) electrical stimulation and pulsed electromagnetic field therapy (PEMF) on augmentation of instrumented lumbar fusion. Sixty-one patients undergoing lumbar spine fusion were enrolled in the study and randomized to one of three treatment protocols: 1) adjunctive PEMF group (n = 22) fitted with Spinal-Stim model 8212(AME) within 30 days of surgery; 2) DC group (n = 17) had a SpF-2T stimulator(EBI) implanted at the time of surgery; or 3) control group (n = 22). The fusion mass bone mineral density (BMD) assessment was performed on 3-month and 1-year radiographs for each patient. Lateral flexion-extension and anteroposterior radiographs were evaluated at 1 year to determine the presence of fusion. Clinical outcome patient analyses were performed at 1 year. At 1-year follow-up, radiographic fusion and fusion mass bone density were not significantly different among the groups. In the nonstimulated group, there were 43% excellent, 43% good, and 14% fair results. In the PEMF group, there were 35% excellent, 50% good, 10% fair, and 5% poor results. In the DC group, there were 32% excellent, 37% good, and 31% fair results. The results of the current study suggest that electrical stimulation does not significantly enhance fusion rate in instrumented lumbar arthrodesis, although we observed a statistically insignificant trend toward increased fusion mass BMD in the electrically stimulated groups. The significance of increased BMD remains unknown.
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Reddy S, Young B, Xue Q, Taha B, Brodnick D, Steinberg J. Review of methods to predict and detect atrial fibrillation in post-cardiac surgery patients. J Electrocardiol 2000; 32 Suppl:23-8. [PMID: 10688299 DOI: 10.1016/s0022-0736(99)90030-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Atrial fibrillation (AF) is the most common sustained arrhythmia after cardiac surgery. Postoperative AF is known to substantially lengthen hospital stay and affect patient recovery. Identification of those at risk of developing AF after surgery and early detection of AF during recovery would be extremely helpful in effective management of these patients, including targeting prophylactic therapy to prevent AF in high-risk patients. In this communication, diagnostic methods to identify those at risk of developing AF after surgery and early identification of AF before, during, and after surgery have been reviewed. Signal-averaged P wave analysis, done before surgery, identifies patients who are likely to develop AF during recovery. When combined with low ejection fraction, signal-averaged P wave can discriminate those who develop AF from those who do not. During recovery, AF can be detected early either from a detailed analysis of atrial activity in a 10-second electrocardiogram or an analysis of R-to-R intervals from an extended rhythm strip (1 minute or longer). Analysis of the 10-second electrocardiogram includes median QRST subtraction from rhythm data and detection and analysis of atrial signals in the resulting residual. AF is detected from extended rhythm strips by using a statistical model to identify the presence of characteristic irregular patterns of R-to-R intervals.
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Allan K, Jordan RC, Ang LC, Taylor M, Young B. Overexpression of cyclin A and cyclin B1 proteins in astrocytomas. Arch Pathol Lab Med 2000; 124:216-20. [PMID: 10656729 DOI: 10.5858/2000-124-0216-oocaac] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Cyclins are proteins that are expressed during the progression of a normal cell through the cell cycle. In a number of cancers, overexpression of cyclin A and cyclin B1 proteins has been reported, and in some instances the levels of expression correlated well with the grades of malignancy. The expression of cyclin A and cyclin B1 proteins in astrocytoma may be linked to the histologic grade or proliferative activities. OBJECTIVE To study the expression of cyclin A and cyclin B1 proteins in astrocytomas and correlate the labeling indices (LIs) of cyclin A and cyclin B1 with histologic grade and Ki-67 LI. DESIGN The surgical biopsy specimens from 65 adults with astrocytomas were reviewed and divided into grades based on the World Health Organization system. The paraffin sections were immunostained using primary antibodies against Ki-67, cyclin A, and cyclin B1. The LIs of these astrocytomas for the 3 different antibodies were determined by computerized image analysis. RESULTS The cyclin A LI showed good correlation with astrocytoma grade and Ki-67 LI. Both the nuclear and cytoplasmic cyclin B LIs correlated well with the tumor grade but showed poor correlation with Ki-67 LI. CONCLUSIONS This study suggests that although both cyclin A and B protein expression are related to the grade of malignancy in astrocytomas, cyclin A levels more generally reflect the proliferative state of these tumors. We also provide indirect evidence that cyclin B1 is associated with the aberrant progression through the G2-M phase checkpoint in astrocytomas.
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Kuritzkes DR, Sevin A, Young B, Bakhtiari M, Wu H, St Clair M, Connick E, Landay A, Spritzler J, Kessler H, Lederman MM. Effect of zidovudine resistance mutations on virologic response to treatment with zidovudine-lamivudine-ritonavir: genotypic analysis of human immunodeficiency virus type 1 isolates from AIDS clinical trials group protocol 315.ACTG Protocol 315 Team. J Infect Dis 2000; 181:491-7. [PMID: 10669331 DOI: 10.1086/315244] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The effect of baseline drug resistance mutations on response to zidovudine, lamivudine, and ritonavir was evaluated in zidovudine-experienced persons infected with human immunodeficiency virus type 1 (HIV-1). Presence of the K70R mutation was associated with significantly higher plasma HIV-1 RNA levels at baseline. However, presence of resistance mutations did not affect the increase in plasma HIV-1 RNA during a 5-week drug washout, nor was there any effect on first-phase virus decay rates after initiation of therapy or on the probability of having plasma HIV-1 RNA levels <100 copies/mL at week 48. Polymorphisms at protease codons 10, 36, and 71 were associated with significantly faster second-phase decay rates. Suppression of plasma HIV-1 RNA despite presence of zidovudine resistance mutations implies that the presence of these mutations does not preclude a durable response to treatment with a potent 3-drug regimen.
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Toborek M, Garrido R, Malecki A, Kaiser S, Mattson MP, Hennig B, Young B. Nicotine attenuates arachidonic acid-induced overexpression of nitric oxide synthase in cultured spinal cord neurons. Exp Neurol 2000; 161:609-20. [PMID: 10686080 DOI: 10.1006/exnr.1999.7308] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Primary spinal cord trauma can initiate a cascade of pathophysiologic events which markedly contribute to the expansion and amplification of the primary insult. The detailed mechanisms of these secondary neurochemical reactions are largely unknown; however, they involve membrane lipid derangements with the release of free fatty acids, in particular, arachidonic acid (AA). AA can induce several injury effects on spinal cord neurons. We hypothesize that upregulation of nitric oxide synthase (NOS) is among the most important mechanisms of arachidonic-acid-induced neuronal dysfunction and that nicotine can attenuate this effect. To study these hypotheses, spinal cord neurons were exposed to AA and/or nicotine, and several markers of neuronal nitric oxide synthase (nNOS) metabolism were measured. In addition, cotreatments with either inhibitors of nicotinic receptors or inhibitors of specific NOS isoforms were employed. Treatment with AA markedly increased activity of nNOS, as well as mRNA and protein levels of this enzyme. Changes in nNOS expression were accompanied by an increase in cellular cGMP and medium nitrite levels. Pretreatment with nicotine decreased AA-induced overexpression of nNOS and elevation of nitrite levels. In addition, it appeared that these nicotine effects could be partially modulated both by the alpha7 nicotinic receptors or by nonreceptor mechanisms. Alternatively, the observed changes could also be mediated by an alternate nicotinic receptor mechanism which is not blocked by alpha-bungarotoxin or mecamylamine. Results of the present study indicate that exposure to AA can lead to induction of nNOS in cultured spinal cord neurons. In addition, nicotine can exert a neuroprotective effect by attenuation of AA-induced upregulation of nNOS metabolism. These data may have therapeutic implications for the treatment of acute spinal cord trauma.
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Smyth ET, McIlvenny G, Thompson IM, Adams RJ, McBride L, Young B, Mitchell E, MacAuley D. Sterilization and disinfection in general practice in Northern Ireland. J Hosp Infect 1999; 43:155-61. [PMID: 10549315 DOI: 10.1053/jhin.1999.0738] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In view of the recent trend towards more minor surgery being carried out in general practice we decided to conduct a postal survey to assess the level of knowledge of sterilization and disinfection and the use of benchtop sterilizers in general practice in Northern Ireland. The survey, of all 366 practices in the Province, was carried out in January/March 1998. One hundred and eleven (30%) completed questionnaires were returned. All practices performed at least one of a range of procedures requiring sterilization or disinfection, e.g., minor surgery 95%, cervical smear taking 98%, syringing of ears 98%. Only 76% of practices had a benchtop sterilizer and 39% did not have access to a sterile supply department (SSD); 32% of the latter had no desire to utilize such a service. Only 25% and 34% correctly identified the Medical Devices Agency (MDA) definitions of sterilization and disinfection respectively. The MDA Device Bulletin on benchtop sterilizers had been read by only 26% of respondents. There was an 86% interest in attending a workshop on sterilization and disinfection. The concepts and practice of sterilization and disinfection appear not to be clearly understood. We conclude that resources must be identified to provide appropriate education in this important area for primary care staff.
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Young B, Kuritzkes DR. Viral kinetics: implications for treatment. AIDS 1999; 13 Suppl 1:S11-7. [PMID: 10546781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Increasing knowledge of the principles of viral dynamics in HIV infection has dramatically changed our understanding of the disease. Basic concepts of viral kinetics and implications for the treatment of HIV-infected persons are reviewed.
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Herd AY, Milligan RG, Young B. Piloting the Institute of Medical Illustrators and Glasgow Caledonian University BSc in medical illustration conversion course. THE JOURNAL OF AUDIOVISUAL MEDIA IN MEDICINE 1999; 22:121-5. [PMID: 10628004 DOI: 10.1080/014051199102061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Diplomates of the Institute of Medical Illustrators (IMI) have a route to converting their existing qualification to a Bachelor of Science (BSc) in Medical Illustration. The experience of a pilot group who undertook this course is described, and advice for potential students is proposed. Additional comments based on the findings and recommendations of the Scrutiny Panel, who have a role in project approval and assessment, have also been included to assist students undertaking the conversion course. Students of this pilot group found the experience of undertaking the conversion course a rewarding exercise, although the effort required to successfully pass should not be underestimated.
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Fox CH, Ramsoomair D, Mahoney MC, Carter C, Young B, Graham R. An investigation of hypomagnesemia among ambulatory urban African Americans. THE JOURNAL OF FAMILY PRACTICE 1999; 48:636-639. [PMID: 10496643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
BACKGROUND Magnesium represents the fourth most abundant cation in the body and plays an integral role in intracellular metabolism. Although magnesium deficiency states have been associated with a variety of medical conditions, the prevalence of hypomagnesemia has not been well studied, particularly in ambulatory settings. METHODS We performed a period prevalence study using 120 patients seen for routine medical care at an urban family medicine center. Chart reviews were completed for these subjects. We used univariate and multivariate analyses to correlate magnesium levels with demographic and clinical factors. RESULTS There was a 20% overall prevalence of hypomagnesemia among this predominantly female, African American population. The prevalence of hypomagnesemia was greatest among patients with a history of alcoholism (odds ratio [OR] = 6.00; 95% confidence interval [CI], 1.41-26.1) and among those having 1 or more of the following medical conditions: diabetes, hyperlipidemia, hypertension, renal disease, and asthma (OR = 4.69; 95% CI, 1.37-17.65). CONCLUSIONS The prevalence of hypomagnesemia among patients from this urban minority community exceeds that reported in previous studies of the general population. This may be reflective of greater comorbidity, diminished nutritional status, or poorer overall health among patients from this community. The association between hyperlipidemia and magnesium deficiency warrants further investigation.
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Young B, Kuritzkes DR. Reply. J Infect Dis 1999; 180:570-1. [PMID: 10395886 DOI: 10.1086/314911] [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] Open
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Toborek M, Malecki A, Garrido R, Mattson MP, Hennig B, Young B. Arachidonic acid-induced oxidative injury to cultured spinal cord neurons. J Neurochem 1999; 73:684-92. [PMID: 10428065 DOI: 10.1046/j.1471-4159.1999.0730684.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Spinal cord trauma can cause a marked release of free fatty acids, in particular, arachidonic acid (AA), from cell membranes. Free fatty acids, and AA by itself, may lead to secondary damage to spinal cord neurons. To study this hypothesis, cultured spinal cord neurons were exposed to increasing concentrations of AA (0.01-10 microM). AA-induced injury to spinal cord neurons was assessed by measurements of cellular oxidative stress, intracellular calcium levels, activation of nuclear factor-KB (NF-kappaB), and cell viability. AA treatment increased intracellular calcium concentrations and decreased cell viability. Oxidative stress increased significantly in neurons exposed to 1 and 10 microM AA. In addition, AA treatment activated NF-kappaB and decreased levels of the inhibitory subunit, IKB. It is interesting that manganese superoxide dismutase protein levels and levels of intracellular total glutathione increased in neurons exposed to this fatty acid for 24 h, consistent with a compensatory response to increased oxidative stress. These results strongly support the hypothesis that free fatty acids contribute to the tissue injury observed following spinal cord trauma.
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Gross CA, Chan C, Dombroski A, Gruber T, Sharp M, Tupy J, Young B. The functional and regulatory roles of sigma factors in transcription. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 1999; 63:141-55. [PMID: 10384278 DOI: 10.1101/sqb.1998.63.141] [Citation(s) in RCA: 288] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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149
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Ang LC, Zhang Y, Cao L, Yang BL, Young B, Kiani C, Lee V, Allan K, Yang BB. Versican enhances locomotion of astrocytoma cells and reduces cell adhesion through its G1 domain. J Neuropathol Exp Neurol 1999; 58:597-605. [PMID: 10374750 DOI: 10.1097/00005072-199906000-00004] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Versican is a large extracellular proteoglycan and is expressed in a variety of tissues including the central nervous system. A malignant astrocytoma cell line U87 with high motility expressed a higher level of versican than another malignant astrocytoma cell line U343 with lower motility. We observed that the U87 cells were less adherent to tissue culture plates than the U343 cells. To investigate the role of versican in astrocytoma cell migration, we generated recombinant products of a mini-versican construct expressed in COS-7 cells. We found that the mini-versican products enhanced astrocytoma cell migration. Furthermore, enhanced migration was promoted by the G1 domain but not the G3 domain of versican. We introduced culture medium containing products of the mini-versican, the G1, and the G3 constructs separately into the astrocytoma cell lines U87 and U343. The mini-versican and the G1 construct, but not the G3 construct, were shown to reduce astrocytoma cell adhesion. The present data suggest that versican exerts its effect on astrocytoma cell migration and adhesion through the G1 domain.
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McLachlan R, Young B. Minimal standards for digital/quantitative electroencephalography in Canada. Can J Neurol Sci 1999; 26:153. [PMID: 10352876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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