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Parrish-Novak J, Dillon SR, Nelson A, Hammond A, Sprecher C, Gross JA, Johnston J, Madden K, Xu W, West J, Schrader S, Burkhead S, Heipel M, Brandt C, Kuijper JL, Kramer J, Conklin D, Presnell SR, Berry J, Shiota F, Bort S, Hambly K, Mudri S, Clegg C, Moore M, Grant FJ, Lofton-Day C, Gilbert T, Rayond F, Ching A, Yao L, Smith D, Webster P, Whitmore T, Maurer M, Kaushansky K, Holly RD, Foster D. Interleukin 21 and its receptor are involved in NK cell expansion and regulation of lymphocyte function. Nature 2000; 408:57-63. [PMID: 11081504 DOI: 10.1038/35040504] [Citation(s) in RCA: 950] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Cytokines are important in the regulation of haematopoiesis and immune responses, and can influence lymphocyte development. Here we have identified a class I cytokine receptor that is selectively expressed in lymphoid tissues and is capable of signal transduction. The full-length receptor was expressed in BaF3 cells, which created a functional assay for ligand detection and cloning. Conditioned media from activated human CD3+ T cells supported proliferation of the assay cell line. We constructed a complementary DNA expression library from activated human CD3+ T cells, and identified a cytokine with a four-helix-bundle structure using functional cloning. This cytokine is most closely related to IL2 and IL15, and has been designated IL21 with the receptor designated IL21 R. In vitro assays suggest that IL21 has a role in the proliferation and maturation of natural killer (NK) cell populations from bone marrow, in the proliferation of mature B-cell populations co-stimulated with anti-CD40, and in the proliferation of T cells co-stimulated with anti-CD3.
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950 |
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Nakagawa T, Roth W, Wong P, Nelson A, Farr A, Deussing J, Villadangos JA, Ploegh H, Peters C, Rudensky AY. Cathepsin L: critical role in Ii degradation and CD4 T cell selection in the thymus. Science 1998; 280:450-3. [PMID: 9545226 DOI: 10.1126/science.280.5362.450] [Citation(s) in RCA: 529] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Degradation of invariant chain (Ii) is a critical step in major histocompatibility complex class II-restricted antigen presentation. Cathepsin L was found to be necessary for Ii degradation in cortical thymic epithelial cells (cTECs), but not in bone marrow (BM)-derived antigen-presenting cells (APCs). Consequently, positive selection of CD4+ T cells was reduced. Because different cysteine proteinases are responsible for specific Ii degradation steps in cTECs and BM-derived APCs, the proteolytic environment in cells mediating positive and negative selection may be distinct. The identification of a protease involved in class II presentation in a tissue-specific manner suggests a potential means of manipulating CD4+ T cell responsiveness in vivo.
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529 |
3
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Itohara S, Mombaerts P, Lafaille J, Iacomini J, Nelson A, Clarke AR, Hooper ML, Farr A, Tonegawa S. T cell receptor delta gene mutant mice: independent generation of alpha beta T cells and programmed rearrangements of gamma delta TCR genes. Cell 1993; 72:337-48. [PMID: 8381716 DOI: 10.1016/0092-8674(93)90112-4] [Citation(s) in RCA: 428] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
T cells bearing T cell receptor (TCR) gamma and delta chain heterodimers are first generated early in ontogeny. They form distinct subsets that differ in their TCR repertoires and tissue distribution. Disruption of the mouse TCR C delta gene segment by a gene targeting method caused the complete loss of T cells bearing TCR gamma delta chains, but had little or no effect on the development of T cells bearing TCR alpha beta chains. The analyses of TCR gamma and delta genes in the mutant mice suggest that intracellular mechanisms acting at the level of DNA rearrangement play key roles in the differential gamma and delta gene rearrangements and in the generation of the highly restricted junctional sequences during fetal thymic development.
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428 |
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Mac Donald R, Baken L, Nelson A, Nichol KL. Validation of self-report of influenza and pneumococcal vaccination status in elderly outpatients. Am J Prev Med 1999; 16:173-7. [PMID: 10198654 DOI: 10.1016/s0749-3797(98)00159-7] [Citation(s) in RCA: 332] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To assess the validity of self-reported influenza and pneumococcal vaccination status. DESIGN Cross-sectional surveys of outpatients aged 65 years or older. SETTING A Veterans Affairs Medical Center (VA) and a community managed care organization (MCO). Both organizations have organized influenza and pneumococcal vaccination programs. SUBJECTS VA subjects included all elderly respondents to a mailed survey of 500 randomly selected outpatients. MCO subjects included all respondents to a telephone survey of 300 randomly selected elderly members of the MCO. MEASUREMENTS The VA survey was conducted following the 1995-1996 influenza season while the MCO survey was conducted following the 1994-1995 season. Self-report from the mailed survey for VA subjects and from the telephone survey for MCO subjects was compared to medical record documentation (paper and computerized combined). RESULTS The response rate was 77% (n = 369) for the VA subjects of whom 195 (53%) were aged 65 or older. The response rate for the MCO subjects was 84% (n = 237). Self-report of influenza vaccination had a sensitivity (SENS) of 1.0 and a specificity (SPEC) of .79 with a kappa of .72 (95% CI .58-.86) among VA patients. Among MCO patients, self-report of influenza vaccination had a SENS of .98 and a SPEC of .71 with kappa of .75 (95% CI .69-.89). Self-report of pneumococcal vaccination status among VA patients had a SENS of .97 and a SPEC of .53 with a kappa of .42 (95% CI .32-.52). Among MCO patients, self-report of pneumococcal vaccination had a SENS of .90 and a SPEC of .64 with a kappa of .54 (95% CI .40-.68). A secondary analysis excluding subjects living outside of the VA's catchment area improved the specificity and indices of concordance of self-report of both influenza and pneumococcal vaccination. A secondary analysis of MCO data which excluded subjects who received a pneumococcal vaccination > 2 years prior to the study also improved concordance and the negative predictive value of self-report. CONCLUSIONS Self-report of influenza vaccination is a highly sensitive and moderately specific measure. Self-report of pneumococcal vaccination is also a highly sensitive but less specific measure of vaccination status. Lower rates of validity for pneumococcal vaccination may reflect both less accurate recall, particularly for more distant vaccination, and less complete documentation in medical records.
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Perell KL, Nelson A, Goldman RL, Luther SL, Prieto-Lewis N, Rubenstein LZ. Fall risk assessment measures: an analytic review. J Gerontol A Biol Sci Med Sci 2001; 56:M761-6. [PMID: 11723150 DOI: 10.1093/gerona/56.12.m761] [Citation(s) in RCA: 284] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Clinicians are often unaware of the many existing scales for identifying fall risk and are uncertain about how to select an appropriate one. Our purpose was to summarize existing fall risk assessment scales to enable more informed choices regarding their use. METHODS After a systematic literature search, 21 articles published from 1984 through 2000 describing 20 fall risk assessments were reviewed independently for content and validation by a panel of five reviewers using a standardized review form. Fourteen were institution-focused nursing assessment scales, and six were functional assessment scales. RESULTS The majority of the scales were developed for elderly populations, mainly in hospital or nursing home settings. The patient characteristics assessed were quite similar across the nursing assessment forms. The time to complete the form varied from less than 1 minute to 80 minutes. For those scales with reported diagnostic accuracy, sensitivity varied from 43% to 100% (median = 80%), and specificity varied from 38% to 96% (median = 75%). Several scales with superior diagnostic characteristics were identified. CONCLUSIONS A substantial number of fall risk assessment tools are readily available and assess similar patient characteristics. Although their diagnostic accuracy and overall usefulness showed wide variability, there are several scales that can be used with confidence as part of an effective falls prevention program. Consequently, there should be little need for facilities to develop their own scales. To continue to develop fall risk assessments unique to individual facilities may be counterproductive because scores will not be comparable across facilities.
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Review |
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Nichol KL, Baken L, Nelson A. Relation between influenza vaccination and outpatient visits, hospitalization, and mortality in elderly persons with chronic lung disease. Ann Intern Med 1999; 130:397-403. [PMID: 10068413 DOI: 10.7326/0003-4819-130-5-199903020-00003] [Citation(s) in RCA: 239] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Influenza vaccine is underused in groups targeted for vaccination. OBJECTIVE To define the effects of influenza and the benefits of influenza vaccination in elderly persons with chronic lung disease. DESIGN Retrospective, multiseason cohort study. SETTING Large managed care organization. PATIENTS All elderly members of a managed care organization who had a previous diagnosis of chronic lung disease. MEASUREMENTS Outcomes in vaccinated and unvaccinated persons for the 1993-1994, 1994-1995, and 1995-1996 influenza seasons were compared after adjustment for baseline demographic and health characteristics. All data were obtained from administrative databases. RESULTS Vaccination rates were greater than 70% for each season. Among unvaccinated persons, hospitalization rates for pneumonia and influenza were twice as high in the influenza seasons as they were in the interim (noninfluenza) periods. Influenza vaccination was associated with fewer hospitalizations for pneumonia and influenza (adjusted risk ratio, 0.48 [95% CI, 0.28 to 0.82]) and with lower risk for death (adjusted odds ratio, 0.30 [CI, 0.21 to 0.43]) during the influenza seasons. It was also associated with fewer outpatient visits for pneumonia and influenza and for all respiratory conditions. CONCLUSIONS For elderly persons with chronic lung disease, influenza is associated with significant adverse health effects and influenza vaccination is associated with substantial health benefits, including fewer outpatient visits, fewer hospitalizations, and fewer deaths. Health care providers should take advantage of all opportunities to immunize these high-risk patients.
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239 |
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Cusack B, Nelson A, Richelson E. Binding of antidepressants to human brain receptors: focus on newer generation compounds. Psychopharmacology (Berl) 1994; 114:559-65. [PMID: 7855217 DOI: 10.1007/bf02244985] [Citation(s) in RCA: 226] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Using radioligand binding assays and post-mortem normal human brain tissue, we obtained equilibrium dissociation constants (Kds) for 17 antidepressants and two of their metabolites at histamine H1, muscarinic, alpha 1-adrenergic, alpha 2-adrenergic, dopamine D2, serotonin 5-HT1A, and serotonin 5-HT2 receptors. Several newer antidepressants were compared with older drugs. In addition, we studied some antimuscarinic, antiparkinson, antihistamine, and neuroleptic compounds at some of these receptors. For the antidepressants, classical tricyclic antidepressants were the most potent drugs at five of the seven receptors (all but alpha 2-adrenergic and 5-HT1A receptors). The chlorophenylpiperazine derivative antidepressants (etoperidone, nefazodone, trazodone) were the most potent antidepressants at alpha 2-adrenergic and 5-HT1A receptors. Of ten antihistamines tested, none was more potent than doxepin at histamine H1 receptors. At muscarinic receptors antidepressants and antihistamines had a range of potencies, which were mostly weaker than those for antimuscarinics. From the in vitro data, we expect adinazolam, bupropion, fluoxetine, sertraline, tomoxetine, and venlafaxine not to block any of these five receptors in vivo. An antidepressant's potency for blocking a specific receptor is predictive of certain side effects and drug-drug interactions. These studies can provide guidelines for the clinician in the choice of antidepressant.
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MESH Headings
- Antidepressive Agents/pharmacokinetics
- Brain/metabolism
- Humans
- In Vitro Techniques
- Radioligand Assay
- Receptors, Adrenergic, alpha-1/metabolism
- Receptors, Adrenergic, alpha-2/metabolism
- Receptors, Cell Surface/drug effects
- Receptors, Cell Surface/metabolism
- Receptors, Dopamine D2/metabolism
- Receptors, Histamine H1/metabolism
- Receptors, Muscarinic/metabolism
- Receptors, Serotonin/metabolism
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226 |
8
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24 |
215 |
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Nichol KL, Baken L, Wuorenma J, Nelson A. The health and economic benefits associated with pneumococcal vaccination of elderly persons with chronic lung disease. ARCHIVES OF INTERNAL MEDICINE 1999; 159:2437-42. [PMID: 10665892 DOI: 10.1001/archinte.159.20.2437] [Citation(s) in RCA: 213] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND More than 50% of the elderly population has not received pneumococcal vaccination. Uncertainty regarding the benefits of immunization, particularly for noninvasive disease, may contribute to the underuse of pneumococcal vaccine. OBJECTIVE To assess the health and economic benefits associated with pneumococcal vaccination. METHODS We conducted a 2-year retrospective cohort study among all elderly members of a staff-model managed care organization who had a baseline diagnosis of chronic lung disease. The study outcomes were assessed over 2 years, from November 15, 1993, through November 14, 1995, and included hospitalizations for pneumonia and influenza, death, and hospitalization costs. Using administrative data, we compared these outcomes for vaccinated and unvaccinated subjects using multivariate models to control for subjects' baseline demographic and health characteristics. The additive benefits of combined influenza and pneumococcal vaccination were also assessed for the 2 influenza seasons included in the study. RESULTS There were 1898 subjects. Pneumococcal vaccination was associated with significantly lower risks for pneumonia hospitalizations (adjusted risk ratio [RR], 0.57; 95% confidence interval [CI], 0.38-0.84; P=.005) and for death (adjusted RR, 0.71; 95% CI, 0.56-0.91; P = .008). For the control outcome of all nonpneumonia hospitalizations, rates did not differ significantly between the 2 groups (adjusted RR, 0.91; 95% CI, 0.77-1.07; P= .24). During the influenza seasons included in the study, the benefits of pneumococcal and influenza vaccinations were additive, with an adjusted RR of 0.28 (95% CI, 0.14-0.58; P<.001) for the number of hospitalizations for pneumonia and influenza among persons who had received both vaccinations compared with those who had received neither and an adjusted odds ratio of 0.18 (95% CI, 0.11-0.31; P<.001) for death. Over the 2-year outcome period, pneumococcal vaccination was also associated with direct medical care cost savings. CONCLUSIONS Pneumococcal vaccination of elderly persons with chronic lung disease was associated with fewer hospitalizations for pneumonia, fewer deaths, and direct medical care cost savings.
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213 |
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Balk DL, Deichmann U, Yetman G, Pozzi F, Hay SI, Nelson A. Determining global population distribution: methods, applications and data. ADVANCES IN PARASITOLOGY 2006; 62:119-56. [PMID: 16647969 PMCID: PMC3154651 DOI: 10.1016/s0065-308x(05)62004-0] [Citation(s) in RCA: 208] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Evaluating the total numbers of people at risk from infectious disease in the world requires not just tabular population data, but data that are spatially explicit and global in extent at a moderate resolution. This review describes the basic methods for constructing estimates of global population distribution with attention to recent advances in improving both spatial and temporal resolution. To evaluate the optimal resolution for the study of disease, the native resolution of the data inputs as well as that of the resulting outputs are discussed. Assumptions used to produce different population data sets are also described, with their implications for the study of infectious disease. Lastly, the application of these population data sets in studies to assess disease distribution and health impacts is reviewed. The data described in this review are distributed in the accompanying DVD.
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Review |
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208 |
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Richelson E, Nelson A. Antagonism by neuroleptics of neurotransmitter receptors of normal human brain in vitro. Eur J Pharmacol 1984; 103:197-204. [PMID: 6149136 DOI: 10.1016/0014-2999(84)90478-3] [Citation(s) in RCA: 163] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Using radioligand binding techniques, we determined the equilibrium dissociation constants (KD's) for a series of neuroleptics at the dopamine (D-2), muscarinic, histamine H1, alpha 1- and alpha 2-adrenergic receptors of normal human brain tissue obtained at autopsy. Seventeen different compounds were studied at the D-2 receptor and 15 compounds at the remaining receptors. At the D-2 receptor of caudate nucleus, spiperone was the most potent compound (KD = 0.16 nM); clozapine the least potent (KD = 180 nM). The KD's for six compounds at the D-2 receptor of nucleus accumbens were not significantly different from their respective KD's in the caudate nucleus. The most potent and least potent compounds at the other receptors were clozapine and molindone at the muscarinic receptor, mesoridazine and molindone at the H1 receptor, spiperone and molindone at the alpha 1-receptor, and clozapine and haloperidol at the alpha 2-receptor, respectively.
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163 |
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Abstract
Bedside cognitive screening instruments are used increasingly in clinical and research settings to detect cognitive impairment and to quantify its severity. The authors review the five most frequently cited bedside screening tests that use an interview format and require brief administration times: the Mini-Mental State Examination, the Cognitive Capacity Screening Examination, Mattis Dementia Rating Scale, Kahn's Mental Status Questionnaire, and the Short Portable Mental Status Questionnaire. The tests all have adequate inter-rater reliability, and adequate test-retest reliability has been established for three of the tests. All of the tests show close correspondence with clinical diagnoses of delirium and dementia and are useful for the diagnosis and quantification of these syndromes. However, there is currently no evidence that the tests increase the level of diagnostic accuracy achieved through clinical examination alone. All of the tests have substantial false-negative rates, with false-negative errors frequent among patients with focal lesions, particularly of the right hemisphere. False-positive errors may be more common among patients with less education and lower socioeconomic status. The tests reviewed do not detect many types of cognitive deficit that may bear critically on differential diagnosis and case management. Suggestions are given for further research on the current measures and for the development of new screening tests that would meet a broader range of clinical purposes.
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149 |
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Stewart CJ, Marrs ECL, Magorrian S, Nelson A, Lanyon C, Perry JD, Embleton ND, Cummings SP, Berrington JE. The preterm gut microbiota: changes associated with necrotizing enterocolitis and infection. Acta Paediatr 2012; 101:1121-7. [PMID: 22845166 DOI: 10.1111/j.1651-2227.2012.02801.x] [Citation(s) in RCA: 124] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
AIM To describe gut colonization in preterm infants using standard culture and 16S gene rRNA profiling, exploring differences in healthy infants and those who developed NEC/late onset sepsis (LOS). METHODS Ninety-nine stools from 38 infants of median 27-week gestation were cultured; 44 stools from 27 infants had their microbial profiles determined by 16S. Ordination analyses explored effects of patient variables on gut communities. RESULTS Standard microbiological culture identified a mean of two organisms (range 0-7), DGGE 12 (range 3-18) per patient. Enterococcus faecalis and coagulase negative staphylococci (CONS) were most common by culture (40% and 39% of specimens). Meconium was not sterile. No fungi were cultured. Bacterial community structures in infants with NEC and LOS differed from healthy infants. Infants who developed NEC carried more CONS (45% vs 30%) and less Enterococcus faecalis (31% vs 57%). 16S identified Enterobacter and Staphylococcus presence associated with NEC/LOS, respectively. CONCLUSIONS Important differences were found in the gut microbiota of preterm infants who develop NEC/LOS. The relationship of these changes to current practices in neonatal intensive care requires further exploration.
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13 |
124 |
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Laga M, Icenogle JP, Marsella R, Manoka AT, Nzila N, Ryder RW, Vermund SH, Heyward WL, Nelson A, Reeves WC. Genital papillomavirus infection and cervical dysplasia--opportunistic complications of HIV infection. Int J Cancer 1992; 50:45-8. [PMID: 1309459 DOI: 10.1002/ijc.2910500110] [Citation(s) in RCA: 115] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Certain human genital papillomaviruses (HPV) are strongly associated with cervical dysplasia and cancer. Evidence is accumulating that HPV infection and ano-genital cancers are more common in patients with the acquired immunodeficiency syndrome. The objective of our study was to evaluate the extent to which HPV infection and associated cervical disease constitute opportunistic complications of human immunodeficiency virus (HIV) infection in a population of sexually promiscuous, HIV-infected women in Kinshasa, Zaire. In 1989 we obtained Pap smears and cervicovaginal lavage specimens for HPV DNA testing from 47 HIV-seropositive and 48 HIV-seronegative prostitutes who were part of a cohort under observation since 1988. Thirty-eight percent of the HIV-seropositive and 8% of the seronegative women (odds ratio = 6.8; p = 0.001) had HPV DNA detected by either ViraType, a dot-blot assay which detects specific genital HPV types, or low-stringency Southern blot, which detects all HPV types. Eighty-two women (86%) had an interpretable Pap smear; 11 of 41 (27%) HIV-seropositive women and one of 41 (3%) seronegative women had cervical intra-epithelial neoplasia (CIN) (odds ratio = 14.7; p = 0.002). HIV seropositivity, HPV infection and CIN were highly associated. Eight (73%) of 11 seropositive women with CIN had HPV detected. Both HPV infection and cervical cancer may emerge as opportunistic complications of HIV infection in populations in which HIV, HPV and cervical cancer are common.
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33 |
115 |
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Schultz CL, Alfidi RJ, Nelson AD, Kopiwoda SY, Clampitt ME. The effect of motion on two-dimensional Fourier transformation magnetic resonance images. Radiology 1984; 152:117-21. [PMID: 6729101 DOI: 10.1148/radiology.152.1.6729101] [Citation(s) in RCA: 111] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The effect of motion on two-dimensional Fourier transformation magnetic resonance (MR) images was investigated using phantoms, animals, and normal volunteers. All images were obtained with a 0.30-Tesla superconducting magnet using spin echo pulse sequences. Respiratory motion was simulated while imaging the phantoms. In addition to image blurring, motion produced ghost images, or image harmonics. These ghost images were copies of the static image that was produced at periodic intervals. Canine images, which were obtained during respiration and after the administration of curare, showed significant improvement after respiratory motion was eliminated. Images of normal volunteers were improved with respiratory and cardiac gating, but data acquisition time was significantly increased. These results indicate that MR image quality could be improved with a system that acquires all necessary data within a single breathhold .
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41 |
111 |
16
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Sinden JD, Rashid-Doubell F, Kershaw TR, Nelson A, Chadwick A, Jat PS, Noble MD, Hodges H, Gray JA. Recovery of spatial learning by grafts of a conditionally immortalized hippocampal neuroepithelial cell line into the ischaemia-lesioned hippocampus. Neuroscience 1997; 81:599-608. [PMID: 9316014 DOI: 10.1016/s0306-4522(97)00330-8] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Transient global cerebral ischaemia in rats causes relatively circumscribed and specific damage to the CA1 pyramidal cells of the dorsal hippocampus, along with a cognitive deficit manifest as difficulties in the performance of a range of spatial learning and memory tasks. Our previous studies have shown that restoration of behavioural performance in ischaemic rats by neural grafts taken relatively late in fetal development occurs only after local replacement of cells homotypic to those lost through the ischaemic insult. This lesion-plus-behaviour model therefore offers a powerful means for establishing whether multipotent embryonic neuroepithelial cells will engraft the damaged CA1, develop into appropriate neuronal phenotypes and produce behavioural recovery. Here we report that, in rats subjected to 15 min of global cerebral ischaemia, intrahippocampal implants of a conditionally immortal, multipotent cell line, directly derived from the embryonic day 14 hippocampal neuroepithelium of the H-2Kb-tsA58 transgenic mouse, selectively repopulated the lesioned CA1 pyramidal layer and restored ischaemia-induced deficits in acquisition of a hidden platform location in the Morris water maze.
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17
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Nzila N, Laga M, Thiam MA, Mayimona K, Edidi B, Van Dyck E, Behets F, Hassig S, Nelson A, Mokwa K. HIV and other sexually transmitted diseases among female prostitutes in Kinshasa. AIDS 1991; 5:715-21. [PMID: 1883543 DOI: 10.1097/00002030-199106000-00011] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In 1988, 1233 prostitutes from different geographic areas of Kinshasa participated in a cross-sectional survey on HIV infection and other sexually transmitted diseases (STDs). Despite relatively good knowledge about AIDS and STDs, the reported preventive behaviour was poor. Only 12% of the women reported regular use of condoms, while greater than 50% of the women reported regular use of antibiotics and 38% reported doing nothing specific to prevent STDs. Thirty-five per cent of the women were HIV-positive compared with 27% in a similar survey in Kinshasa in 1986. The prevalence of other STDs was very high, ranging from 5% for genital ulcer disease (GUD) to 23% for gonococcal infection. HIV-positive women were older than HIV-negative women (26.9 versus 25.4 years; P less than 0.001), had a significantly lower level of reported condom use (9 versus 14%, P = 0.009), and reported more frequent use of antibiotics to prevent STDs (55 versus 42%, P = less than 0.001). The prevalence of syphilis, gonorrhoea, chlamydial infection and trichomoniasis was not higher in HIV-positive women compared with HIV-negative women. However, HIV-positive women had a higher prevalence of GUD (9 versus 3%, P less than 0.001), antibodies against Haemophilus ducreyi (82 versus 57%, P less than 0.001), antibodies against herpes simplex virus type 2 (96 versus 76%, P less than 0.001), condylomata accuminata (5 versus 1%, P = 0.003) and cytologic evidence of human papilloma virus on Papaniclaou cervical smear (11 versus 5%, P = 0.006). This study confirms the high incidence of HIV and other STDs among prostitutes in Africa.(ABSTRACT TRUNCATED AT 250 WORDS)
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Fletcher BD, Jacobstein MD, Nelson AD, Riemenschneider TA, Alfidi RJ. Gated magnetic resonance imaging of congenital cardiac malformations. Radiology 1984; 150:137-40. [PMID: 6689753 DOI: 10.1148/radiology.150.1.6689753] [Citation(s) in RCA: 102] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Magnetic resonance (MR) images of a variety of cardiac malformations in 19 patients aged 1 week to 33 years were obtained using pulse plethysmographic- or ECG-gated spin echo pulse sequences. Coronal, axial, and sagittal images displaying intracardiac structures with excellent spatial and contrast resolution were acquired during systole or diastole. It is concluded that MR will be a valuable noninvasive method of diagnosing congenital heart disease.
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Comparative Study |
41 |
102 |
19
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Laakman RW, Kaufman B, Han JS, Nelson AD, Clampitt M, O'Block AM, Haaga JR, Alfidi RJ. MR imaging in patients with metallic implants. Radiology 1985; 157:711-4. [PMID: 4059558 DOI: 10.1148/radiology.157.3.4059558] [Citation(s) in RCA: 94] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A total of 305 magnetic resonance (MR) examinations were performed in 236 patients with metallic implants. Most examinations were performed at 0.3 T. The metallic implants included central nervous system shunting devices, tantalum mesh, surgical wire, skin staples, surgical clips, metallic orthopedic devices, and a few miscellaneous metallic objects. Patients with cardiac pacemakers, electrical implants, prosthetic cardiac valves, and aneurysm clips were excluded from MR examinations. The images were reviewed for evidence of metallic artifact. The conspicuity of artifact was related to the composition, mass, orientation, and position of the metallic object in the body. In most instances, the metallic artifact did not interfere with the interpretation of the image. The patients' records were also reviewed for adverse effects noted by each patient during the MR examination. Only two patients reported discomfort that could possibly have been related to their metallic implants, but in both cases it seemed unlikely that the symptoms were actually related to the imaging process. There were no apparent short-term adverse effects demonstrated in these patients.
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40 |
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Lee JF, Barrett-O'Keefe Z, Garten RS, Nelson AD, Ryan JJ, Nativi JN, Richardson RS, Wray DW. Evidence of microvascular dysfunction in heart failure with preserved ejection fraction. Heart 2015; 102:278-84. [PMID: 26567228 DOI: 10.1136/heartjnl-2015-308403] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 10/15/2015] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVE While vascular dysfunction is well defined in patients with heart failure (HF) with reduced ejection fraction (HFrEF), disease-related alterations in the peripheral vasculature of patients with HF with preserved ejection fraction (HFpEF) are not well characterised. Thus, we sought to test the hypothesis that patients with HFpEF would demonstrate reduced vascular function, at the conduit artery and microvascular levels, compared with controls. METHODS We examined conduit artery function via brachial artery flow-mediated dilation (FMD) and microvascular function via reactive hyperaemia (RH) following 5 min of ischaemia in 24 patients with Class II-IV HFpEF and 24 healthy controls matched for age, sex and brachial artery diameter. RESULTS FMD was reduced in patients with HFpEF compared with controls (HFpEF: 3.1±0.7%; CONTROLS 5.1±0.5%, p=0.03). However, shear rate at time of peak brachial artery dilation was lower in patients with HFpEF compared with controls (HFpEF: 42 070±4018/s; CONTROLS 69 018±9509/s, p=0.01), and when brachial artery FMD was normalised for the shear stimulus, cumulative area-under-the-curve (AUC) at peak dilation, the between-group differences were eliminated (HFpEF: 0.11±0.03%/AUC; CONTROLS 0.09±0.01%/AUC, p=0.58). RH, assessed as AUC, was lower in patients with HFpEF (HFpEF: 454±35 mL; CONTROLS 660±63 mL, p<0.01). CONCLUSIONS Collectively, these data suggest that maladaptations at the microvascular level contribute to the pathophysiology of HFpEF, while conduit artery vascular function is not diminished beyond that which occurs with healthy aging.
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Research Support, U.S. Gov't, Non-P.H.S. |
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Nelson AD, Mouchli MA, Valentin N, Deyle D, Pichurin P, Acosta A, Camilleri M. Ehlers Danlos syndrome and gastrointestinal manifestations: a 20-year experience at Mayo Clinic. Neurogastroenterol Motil 2015; 27:1657-66. [PMID: 26376608 DOI: 10.1111/nmo.12665] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 08/01/2015] [Indexed: 02/06/2023]
Abstract
BACKGROUND Gastrointestinal (GI) manifestations are found in Ehlers Danlos syndrome (EDS) hypermobility subtype (HM). We aimed to assess associations between EDS HM and other EDS subtypes with GI manifestations. METHODS We reviewed medical records of EDS patients evaluated at Mayo Clinic's Medical Genetics Clinic 1994-2013. We extracted information regarding EDS subtypes, GI manifestations, and treatments. KEY RESULTS We identified 687 patients; 378 (56%) had associated GI manifestations (female 86.8%, diagnosis mean age 29.6 years). Of the patients identified, 58.9% (43/73) had EDS classic, 57.5% (271/471) EDS HM, 47.3% (27/57) EDS vascular subtypes. In addition, 86 patients had EDS that could not be classified in any of those three subtypes. Commonest GI symptoms were: abdominal pain (56.1%), nausea (42.3%), constipation (38.6%), heartburn (37.6%), and irritable bowel syndrome-like symptoms (27.5%). Many GI symptoms were commoner in EDS HM than the other subtypes together. Among 37.8% of the 378 patients who underwent esophagogastroduodenoscopy, the commonest abnormalities were gastritis, hiatal hernia and reflux esophagitis. Abnormal gastric emptying was observed in 22.3% (17/76): 11.8% delayed and 10.5% accelerated. Colonic transit was abnormal in 28.3% (13/46): 19.6% delayed and 8.7% accelerated. Rectal evacuation disorder was confirmed in 18/30 patients who underwent anorectal manometry. Angiography showed aneurysms in abdominal vessels in EDS vascular type. Proton pump inhibitors (38%) and drugs for constipation (23%) were the most commonly used medications. A minority underwent colectomy (2.9%) or small bowel surgery (4%). CONCLUSIONS & INFERENCES EDS HM and other subtypes should be considered in patients with chronic functional GI symptoms and abdominal vascular lesions.
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Fletcher BD, Scoles PV, Nelson AD. Osteomyelitis in children: detection by magnetic resonance. Work in progress. Radiology 1984; 150:57-60. [PMID: 6689788 DOI: 10.1148/radiology.150.1.6689788] [Citation(s) in RCA: 89] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Magnetic resonance (MR) imaging was performed in five children, ages 9 to 12, with acute, subacute, chronic, and recurrent osteomyelitis. Saturation recovery (SR), T2-weighted spin echo, and inversion recovery (IR) pulse sequences were employed. A reduction in the normally bright image of bone marrow corresponded with abnormalities seen on radiographs, CT scans, and radionuclide scans. SR images produced the best signal-to-noise ratios. Contrast between normal and abnormal marrow was most pronounced on IR sequences, which suggested an increase in water content of inflamed marrow. Abnormalities were sometimes seen on MR images before they could be detected on radiographs. Some MR abnormalities were present when CT and radionuclide studies were normal or equivocal.
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Comparative Study |
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Walsh T, Grimes D, Frezieres R, Nelson A, Bernstein L, Coulson A, Bernstein G. Randomised controlled trial of prophylactic antibiotics before insertion of intrauterine devices. IUD Study Group. Lancet 1998; 351:1005-8. [PMID: 9546505 DOI: 10.1016/s0140-6736(97)09086-7] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND The value of antibiotic prophylaxis before insertion of an intrauterine device (IUD) remains uncertain. We undertook a triple-masked, randomised, placebo-controlled trial to find out whether such prophylaxis reduces the rate of IUD removal within 90 days. METHODS 11 clinic sites in southern California enrolled women who requested IUD insertion and were at low risk of sexually transmitted infection according to self-reported medical history. We randomly assigned 1985 participants either 500 mg azithromycin or placebo capsules of identical appearance taken about 1 h before insertion of a Copper T 380A IUD. 118 women did not have an IUD inserted. We followed up 1833 of the remaining 1867 (98%) participants for at least 90 days after insertion. FINDINGS The rate of IUD removal for any reason other than partial expulsion was 3.8% (35/918) in the antibiotic group and 3.4% (31/915) in the placebo group (relative risk 1.1 [95% CI 0.7-1.8]). The two treatment groups sought medical attention with equal frequency (mean 38 visits per 100 women). During the 90 days after IUD insertion, only one woman from each assignment group had salpingitis, as defined by established criteria. INTERPRETATION Prophylaxis with azithromycin did not affect the likelihood that a woman would retain her IUD at 90 days or the frequency of postinsertion medical attention. In appropriately screened women, the risk of upper-genital-tract infection is negligible after IUD insertion, with or without the administration of prophylactic antibiotics.
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Clinical Trial |
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Cheung NK, Landmeier B, Neely J, Nelson AD, Abramowsky C, Ellery S, Adams RB, Miraldi F. Complete tumor ablation with iodine 131-radiolabeled disialoganglioside GD2-specific monoclonal antibody against human neuroblastoma xenografted in nude mice. J Natl Cancer Inst 1986; 77:739-45. [PMID: 3091900 DOI: 10.1093/jnci/77.3.739] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The antibody 3F8, an IgG3 murine monoclonal antibody (MoAb) against disialoganglioside GD2, could target iodine-131 (131I) to established subcutaneous human neuroblastoma (NB) xenografts in BALB/c nude mice. 131I-radiolabeled MoAb (0.125-1 mCi) was injected iv. Tumor radioactivity over time was calculated from scintigraphy, and radiation dose to individual tumors was calculated. Tumor shrinkage occurred only with 131I-labeled 3F8, but not with nonradioactive 3F8 or radiolabeled irrelevant antibody. While the tumor of the control mice enlarged by tenfold, the treated tumor showed over 95% shrinkage by 12 days. Both the rate of shrinkage and duration of tumor response were dose dependent. Calculated doses of more than 10,000 rad could be achieved. Only those tumors that received more than 4,200 rad were completely ablated without recurrence. Recurrent tumors were not antigen negative or radioresistant. These results confirmed the prediction based on imaging studies that human NB xenografts could be effectively eradicated with the use of 131I-labeled MoAb 3F8 with tolerable toxicities.
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Carvajal-Yepes M, Cardwell K, Nelson A, Garrett KA, Giovani B, Saunders DGO, Kamoun S, Legg JP, Verdier V, Lessel J, Neher RA, Day R, Pardey P, Gullino ML, Records AR, Bextine B, Leach JE, Staiger S, Tohme J. A global surveillance system for crop diseases. Science 2020; 364:1237-1239. [PMID: 31249049 DOI: 10.1126/science.aaw1572] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Journal Article |
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84 |