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Gillespie GM, Wills MR, Appay V, O'Callaghan C, Murphy M, Smith N, Sissons P, Rowland-Jones S, Bell JI, Moss PA. Functional heterogeneity and high frequencies of cytomegalovirus-specific CD8(+) T lymphocytes in healthy seropositive donors. J Virol 2000; 74:8140-50. [PMID: 10933725 PMCID: PMC112348 DOI: 10.1128/jvi.74.17.8140-8150.2000] [Citation(s) in RCA: 338] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/1999] [Accepted: 05/02/2000] [Indexed: 11/20/2022] Open
Abstract
Human cytomegalovirus (HCMV) infection is largely asymptomatic in the immunocompetent host, but remains a major cause of morbidity in immunosuppressed individuals. Using the recently described technique of staining antigen-specific CD8(+) T cells with peptide-HLA tetrameric complexes, we have demonstrated high levels of antigen-specific cells specific for HCMV peptides and show that this may exceed 4% of CD8(+) T cells in immunocompetent donors. Moreover, by staining with tetramers in combination with antibodies to cell surface markers and intracellular cytokines, we demonstrate functional heterogeneity of HCMV-specific populations. A substantial proportion of these are effector cytotoxic T lymphocytes, as demonstrated by their ability to lyse peptide-pulsed targets in "fresh" killing assays. These data suggest that the immune response to HCMV is periodically boosted by a low level of HCMV replication and that sustained immunological surveillance contributes to the maintenance of host-pathogen homeostasis. These observations should improve our understanding of the immunobiology of persistent viral infection.
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Freeman B, Smith N, Curtis C, Huckett L, Mill J, Craig IW. DNA from buccal swabs recruited by mail: evaluation of storage effects on long-term stability and suitability for multiplex polymerase chain reaction genotyping. Behav Genet 2003; 33:67-72. [PMID: 12645823 DOI: 10.1023/a:1021055617738] [Citation(s) in RCA: 257] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We provide details of an inexpensive and rapid method for extraction of DNA from buccal swabs (including samples received through the mail) and from a range of other tissue samples. The procedure we have developed provides amounts of DNA adequate for several thousand polymerase chain reactions (PCRs), and we have validated its potential for long-term storage. Samples stored for > 4 years are of comparable concentration and provide as robust PCR templates as those tested immediately after extraction. The availability of this technology is of considerable significance in planning DNA banks from population collections and cohorts.
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22 |
257 |
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Lee HC, Mohabir R, Smith N, Franz MR, Clusin WT. Effect of ischemia on calcium-dependent fluorescence transients in rabbit hearts containing indo 1. Correlation with monophasic action potentials and contraction. Circulation 1988; 78:1047-59. [PMID: 2844438 DOI: 10.1161/01.cir.78.4.1047] [Citation(s) in RCA: 217] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The effects of acute global ischemia on cytosolic calcium transients were studied in perfused rabbit hearts loaded with the fluorescent calcium indicator indo 1. Indo 1-loaded hearts were illuminated at 360 nm, and fluorescence was recorded simultaneously at 400 and 550 nm from the epicardial surface of the left ventricle. The F400/F550 ratio was calculated by an analog circuit, which allowed cancellation of optical motion artifact. Resulting calcium transients demonstrated a rapid upstroke and slow decay similar to those recorded in isolated ventricular myocytes. Global ischemia rapidly suppressed contraction, but it produced a concurrent increase in the systolic and diastolic levels of the calcium transients, together with an increase in the duration of the peak. The effects of ischemia were reversed by reperfusion, inhibited by verapamil, and mimicked by perfusion of nonischemic hearts with acidified (CO2-rich) solution. In addition to elevation of the calcium transients, ischemia caused a pattern of intracellular calcium alternans that was discernible after 2-3 minutes. The pattern of alternans was stable at a given epicardial site, but it could be out of phase at different sites. Similar nonuniformities were observed in contraction strength and in the duration of monophasic action potentials recorded immediately adjacent to the fiber-optic probe. Abnormalities in intracellular calcium may be a causal factor in the loss of electrical and mechanical synchrony in the acutely ischemic heart.
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217 |
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Smith N, McAnulty JH, Rahimtoola SH. Severe aortic stenosis with impaired left ventricular function and clinical heart failure: results of valve replacement. Circulation 1978; 58:255-64. [PMID: 668073 DOI: 10.1161/01.cir.58.2.255] [Citation(s) in RCA: 210] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Nineteen patients, aged 58-80 years, with severe isolated aortic valve stenosis, severely reduced ejection fraction and clinical heart failure underwent aortic valve replacement between January 1970 and April 1977. Ten had concomitant coronary artery disease (all underwent additional coronary bypass surgery), 17 had angina pectoris and four had syncope. Aortic valve area index was 0.32 +/- 0.03 cm2/m2 (mean +/- SEM); left ventricular (LV) end-diastolic volume index was 117 +/- 9 ml/m2 and LV ejection fraction was 0.37 +/- 0.02. There were four operative deaths and one late death. The follow-up time ranged from six to 74 months (38 +/- 6 months). Actuarially determined three-year survival is 74 +/- 10%; the expected five-year survival is the same. One patient had a serious cerebrovascular accident. Of the remaining survivors, seven were initially Functional Class IV and six Class III; currently, six are Class I and seven Class II (New York Heart Association classifications). The cardiothoracic ratio has decreased from 0.54 +/- 0.03 to 0.49 +/- 0.03. Repeat hemodynamic evaluation has been performed in 10 patients, 22 +/- 6 months after surgery. In these 10 patients, the aortic valve gradient decreased from 55 +/- 7 11 +/- 1.3 mm Hg; LV end-diastolic pressure from 22 +/- 2.4 to 9 +/- 1.9 mm Hg; LV end-diastolic volume index from 119 +/- 16 ml/m2 to 107 +/- 11 ml/m2. LV ejection fraction has increased dramatically from 0.34 +/- 0.03 to 0.63 +/- 0.05 and mean velocity of circumferential fiber shortening from 0.57 +/- 0.08 to 1.3 +/- 0.18 circ/sec. The encouraging long-term survival, improved functional class and the marked improvement in left ventricular function that occurred in our patients indicate that all patients with severe aortic stenosis in clinical heart failure should be offered aortic valve replacement.
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210 |
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Gurwitz JH, Glynn RJ, Monane M, Everitt DE, Gilden D, Smith N, Avorn J. Treatment for glaucoma: adherence by the elderly. Am J Public Health 1993; 83:711-6. [PMID: 8484454 PMCID: PMC1694682 DOI: 10.2105/ajph.83.5.711] [Citation(s) in RCA: 204] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVES The purpose of this study was to determine the extent of nonadherence to treatment for glaucoma among elderly patients. METHODS This was a retrospective cohort study of 2440 patients older than age 65 who were enrolled in the New Jersey Medicaid Program and who were newly initiated on a topical agent for the treatment of glaucoma. Two patient-specific measures of nonadherence were employed: (1) no filled prescription for any glaucoma medication over a 12-month period after the initiation of therapy and (2) number of days without therapy for glaucoma during this 12-month period. RESULTS By the first measure, 569 patients (23%) were found to be nonadherent. The mean number of days without therapy during the study year was 112. Factors associated with nonadherence included the use of glaucoma medication requiring more than 2 administrations per day and the presence of multiple other medications in the patient's drug regimen. Patients started on multiple glaucoma medication were more adherent than those started on a single agent. Age and sex were not found to be predictors of nonadherence. CONCLUSIONS Substantial nonadherence was found to be common in this population. More attention to the issue of nonadherence could result in important benefits in the preservation of sight.
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research-article |
32 |
204 |
6
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Chidrawar S, Khan N, Wei W, McLarnon A, Smith N, Nayak L, Moss P. Cytomegalovirus-seropositivity has a profound influence on the magnitude of major lymphoid subsets within healthy individuals. Clin Exp Immunol 2009; 155:423-32. [PMID: 19220832 DOI: 10.1111/j.1365-2249.2008.03785.x] [Citation(s) in RCA: 197] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Cytomegalovirus (CMV) infects most individuals and elicits a strong CMV-specific immune response. We have studied the influence of CMV-seropositivity on the size of lymphoid subsets in healthy donors and demonstrate that the virus substantially modulates the peripheral lymphoid pool. CD8(+) T cell numbers are increased in all CMV-seropositive individuals because of a striking 60% increment in the CD8(+) T cell memory pool. The CD45RA(+) resting memory pool is doubled after CMV infection and increases further with age. The magnitude of the naïve CD8(+) T cell pool is dramatically reduced in CMV-seropositive individuals at all ages, and this accelerates the physiological decline by approximately 40 years. The number of CD4(+) effector memory T cells is increased in CMV-seropositive individuals and is differentially accommodated by a reduction in the number of naïve and central memory CD4(+) T cells in young and elderly donors respectively. CMV-seropositivity also increases the total number of B cells in older donors and suppresses the number of CD5(+) B cells. These data reveal that CMV has a profound influence on the immune system of all healthy individuals and add to growing concern regarding the clinical and immunomodulatory significance of CMV infection in healthy donors.
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Research Support, Non-U.S. Gov't |
16 |
197 |
7
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Gibson BES, Todd A, Roberts I, Pamphilon D, Rodeck C, Bolton-Maggs P, Burbin G, Duguid J, Boulton F, Cohen H, Smith N, McClelland DBL, Rowley M, Turner G. Transfusion guidelines for neonates and older children. Br J Haematol 2004; 124:433-53. [PMID: 14984493 DOI: 10.1111/j.1365-2141.2004.04815.x] [Citation(s) in RCA: 195] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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195 |
8
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Smith NF, Acharya MR, Desai N, Figg WD, Sparreboom A. Identification of OATP1B3 as a high-affinity hepatocellular transporter of paclitaxel. Cancer Biol Ther 2006; 4:815-8. [PMID: 16210916 DOI: 10.4161/cbt.4.8.1867] [Citation(s) in RCA: 177] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Interindividual variability in paclitaxel and docetaxel pharmacokinetics, toxicity and response is extensive, and largely unexplained. We hypothesized that this is due to affinity of taxanes for an uptake transporter that indirectly regulates elimination pathways. Here, we studied accumulation of [3H]docetaxel and [3H]paclitaxel in Xenopus laevis oocytes injected with cRNA of the liver-specific organic anion transporting polypeptide (OATP) family members OATP1B1 (OATP2) or OATP1B3 (OATP8). Taxane transport by OATP1B1 expressing oocytes was not significantly different from that by water-injected controls, whereas uptake by OATP1B3 was 2.2-fold higher for docetaxel (p = 0.0007) and 3.3-fold higher for paclitaxel (p < 0.0001). OATP1B3-mediated paclitaxel transport was saturable (Michaelis-Menten constant, 6.79 microM), time-dependent, and highly sensitive to chemical inhibition. Paclitaxel uptake was not inhibited by ketoconazole or tariquidar. However, uptake was inhibited by the formulation excipient Cremophor (74.4% inhibition, p < 0.0001), cyclosporin A (25.2%, p = 0.005), glycyrrhizic acid (24.6%, p = 0.012), and hyperforin (28.4%, p = 0.003). Consistent with this finding, Cremophor was found to significantly affect the hepatic uptake of paclitaxel in mice. These data suggest that OATP1B3 is a key regulator of hepatic uptake, and may therefore play a role in the variable response to treatment with taxanes.
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Research Support, Non-U.S. Gov't |
19 |
177 |
9
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Abstract
The effectiveness of a modified Gallie technique versus Magerl and Seeman transarticular screw fixation was compared in the management of 27 patients with symptomatic atlantoaxial instability. Twelve patients were treated using a modified Gallie technique and postoperative halo vest immobilization. Atlantoaxial arthrodesis occurred in seven (58%) patients, stable fibrous union occurred in one patient, and pseudarthrosis with recurrent instability developed in four (33%) patients. Average followup was 6.9 years. All 15 patients treated using Magerl and Seeman transarticular screw fixation and postoperative soft collar immobilization had atlantoaxial arthrodesis develop. Average duration of followup was 4 years. One patient sustained vertebral artery injury during preparation for screw placement. Magerl and Seeman transarticular screw fixation provides stability and more reliably produces atlantoaxial arthrodesis than the Gallie technique provides in patients with atlantoaxial instability without the need for rigid postoperative bracing. Potential for vertebral artery exists despite apparent accurate screw placement. To ensure that safe transarticular screw placement is possible, preoperative fine cut axial computed tomography with reconstructions is required to assess vertebral artery position and C2 isthmus anatomy. A proportion of patients have anatomy unsuitable for screw placement. Traditional wiring techniques are indicated in these patients.
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Comparative Study |
26 |
162 |
10
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Stimson L, Rowlands MG, Newbatt YM, Smith NF, Raynaud FI, Rogers P, Bavetsias V, Gorsuch S, Jarman M, Bannister A, Kouzarides T, McDonald E, Workman P, Aherne GW. Isothiazolones as inhibitors of PCAF and p300 histone acetyltransferase activity. Mol Cancer Ther 2005; 4:1521-32. [PMID: 16227401 DOI: 10.1158/1535-7163.mct-05-0135] [Citation(s) in RCA: 158] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Histone acetylation plays an important role in regulating the chromatin structure and is tightly regulated by two classes of enzyme, histone acetyltransferases (HAT) and histone deacetylases (HDAC). Deregulated HAT and HDAC activity plays a role in the development of a range of cancers. Consequently, inhibitors of these enzymes have potential as anticancer agents. Several HDAC inhibitors have been described; however, few inhibitors of HATs have been disclosed. Following a FlashPlate high-throughput screen, we identified a series of isothiazolone-based HAT inhibitors. Thirty-five N-substituted analogues inhibited both p300/cyclic AMP-responsive element binding protein-binding protein-associated factor (PCAF) and p300 (1 to >50 micromol/L, respectively) and the growth of a panel of human tumor cell lines (50% growth inhibition, 0.8 to >50 micromol/L). CCT077791 and CCT077792 decreased cellular acetylation in a time-dependent manner (2-48 hours of exposure) and a concentration-dependent manner (one to five times, 72 hours, 50% growth inhibition) in HCT116 and HT29 human colon tumor cell lines. CCT077791 reduced total acetylation of histones H3 and H4, levels of specific acetylated lysine marks, and acetylation of alpha-tubulin. Four and 24 hours of exposure to the compounds produced the same extent of growth inhibition as 72 hours of continuous exposure, suggesting that growth arrest was an early event. Chemical reactivity of these compounds, as measured by covalent protein binding and loss of HAT inhibition in the presence of DTT, indicated that reaction with thiol groups might be important in their mechanism of action. As one of the first series of small-molecule inhibitors of HAT activity, further analogue synthesis is being pursued to examine the potential scope for reducing chemical reactivity while maintaining HAT inhibition.
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20 |
158 |
11
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Yu S, Harding PG, Smith N, Possmayer F. Bovine pulmonary surfactant: chemical composition and physical properties. Lipids 1983; 18:522-9. [PMID: 6688646 DOI: 10.1007/bf02535391] [Citation(s) in RCA: 153] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Bovine pulmonary surfactant was obtained by endotracheal lavage of lungs from newly slaughtered cows followed by differential centrifugation. Lipid extracts of bovine surfactant contained 3% neutral lipid, mainly as cholesterol and diacylglycerol and 97% phospholipid. Phosphatidylcholine (79%) and phosphatidylglycerol (11%) accounted for most of the phospholipids with smaller amounts of phosphatidylethanolamine, phosphatidylinositol, lyso-bis-phosphatidic acid and sphingomyelin. Fatty acid analysis revealed high levels of palmitate in phosphatidylcholine and to a lesser extent phosphatidylglycerol, but not in the other diacylphospholipids. Phosphatidylcholine was 53% disaturated and phosphatidylglycerol was 23% disaturated. Monoenoic species accounted for the major proportion of the remaining lipid. The protein content was 10% as estimated by the Lowry procedure and 5% when determined by amino acid analysis. Extraction with chloroform/methanol removed ca. 90% of the protein but had no effect on the surfactant properties as evaluated by a pulsating bubble technique.
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42 |
153 |
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Russell W, Harrison RF, Smith N, Darzy K, Shalet S, Weetman AP, Ross RJ. Free triiodothyronine has a distinct circadian rhythm that is delayed but parallels thyrotropin levels. J Clin Endocrinol Metab 2008; 93:2300-6. [PMID: 18364382 DOI: 10.1210/jc.2007-2674] [Citation(s) in RCA: 149] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
CONTEXT TSH is known to have a circadian rhythm, but the relationship between this and any rhythm in T(4) and T(3) has not been clearly demonstrated. OBJECTIVE With a view to optimizing thyroid hormone replacement therapy, we have used modern assays for free T(4) (FT4) and free T(3) (FT3) to investigate circadian rhythmicity. SETTING The study was performed at a university hospital. DESIGN AND SUBJECTS This was a cross-sectional study in 33 healthy individuals with 24-h blood sampling (TSH in 33 and FT4 and FT3 in 29 individuals) and cosinor analysis. RESULTS Of the individuals, 100% showed a sinusoidal signal in TSH, for FT4 76%, and for FT3 86% (P < 0.05). For FT4 and FT3, the amplitude was low. For TSH the acrophase occurred at a clock time of 0240 h, and for FT3 approximately 90 minutes later at 0404 h. The group cosinor model predicts that TSH hormone levels remain above the mesor between 2020 and 0820 h, and for FT3 from 2200-1000 h. Cross correlation of FT3 with TSH showed that the peak correlation occurred with a delay of 0.5-2.5 h. When time-adjusted profiles of TSH and FT3 were compared, there was a strong correlation between FT3 and TSH levels (rho = 0.80; P < 0.0001). In contrast, cross correlation revealed no temporal relationship between FT4 and TSH. CONCLUSIONS FT3 shows a circadian rhythm with a periodicity that lags behind TSH, suggesting that the periodic rhythm of FT3 is due to the proportion of T(3) derived from the thyroid. Optimizing thyroid hormone replacement may need to take these rhythms into account.
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Comparative Study |
17 |
149 |
13
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Smith NF, Figg WD, Sparreboom A. Pharmacogenetics of irinotecan metabolism and transport: an update. Toxicol In Vitro 2005; 20:163-75. [PMID: 16271446 DOI: 10.1016/j.tiv.2005.06.045] [Citation(s) in RCA: 147] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2004] [Revised: 03/01/2005] [Accepted: 06/01/2005] [Indexed: 01/02/2023]
Abstract
The anticancer agent irinotecan (CPT-11) is converted to SN-38, which is approximately 100 to 1,000-fold more cytotoxic than the parent drug. The pharmacokinetics of irinotecan are extremely complex and have been the subject of intensive investigation in recent years. Irinotecan is subject to extensive metabolism by various polymorphic enzymes, including CES2 to form SN-38, members of the UGT1A subfamily, and CYP3A4 and CYP3A5, which form several pharmacologically inactive oxidation products. Elimination of irinotecan is also dependent on drug-transporting proteins, notably ABCB1 (P-glycoprotein), ABCC2 (cMOAT) and ABCG2 (BCRP), present on the bile canalicular membrane. The various processes mediating drug elimination, either through metabolic breakdown or excretion, likely impact substantially on interindividual variability in drug handling. This report provides an update on current strategies to individualize irinotecan chemotherapy based on each patient's genetic constitution, which may ultimately lead to more selective use of this agent.
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Review |
20 |
147 |
14
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Perry S, Shaw C, Assassa P, Dallosso H, Williams K, Brittain KR, Mensah F, Smith N, Clarke M, Jagger C, Mayne C, Castleden CM, Jones J, McGrother C. An epidemiological study to establish the prevalence of urinary symptoms and felt need in the community: the Leicestershire MRC Incontinence Study. Leicestershire MRC Incontinence Study Team. JOURNAL OF PUBLIC HEALTH MEDICINE 2000; 22:427-34. [PMID: 11077920 DOI: 10.1093/pubmed/22.3.427] [Citation(s) in RCA: 144] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND The aim of the study was to establish the prevalence of urinary symptoms and felt need in adults. This paper discusses problems with setting thresholds to distinguish cases from non-cases in this field of research. Few studies have provided detailed age- and sex-specific prevalence estimates for felt need in relation to urinary symptoms. METHODS A cross-sectional postal survey was carried out of 15,904 community-dwelling adults aged 40 years or more registered with general practitioners in Leicestershire. Subjects were selected randomly by household from the Leicestershire Health Authority Register. The postal questionnaire consisted of questions on general health, urinary and bowel symptoms, quality of life, service use and demographic characteristics. RESULTS Thirty-four per cent of the sample reported clinically significant symptoms. The prevalence and severity of symptoms increased with age. However, only 2 per cent of the sample reported symptoms that were clinically significant, bothersome and socially disabling. CONCLUSION Urinary symptoms are very common in adults over 40 years of age living in the community. However, symptom-based estimates probably overestimate the level of need for health care in the community. It may be more effective and efficient to target services, in the first instance, on those people who report clinically significant symptoms that are bothersome or socially disabling. A consensus on thresholds and definitions of urinary symptoms is required to standardize clinical and research work and to target services more appropriately.
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25 |
144 |
15
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Bhatnagar RS, Qian JJ, Wedrychowska A, Sadeghi M, Wu YM, Smith N. Design of biomimetic habitats for tissue engineering with P-15, a synthetic peptide analogue of collagen. TISSUE ENGINEERING 1999; 5:53-65. [PMID: 10207189 DOI: 10.1089/ten.1999.5.53] [Citation(s) in RCA: 144] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In tissues, collagen forms the scaffold for cell attachment and migration, and it modulates cell differentiation and morphogenesis by mediating the flux of chemical and mechanical stimuli. We are constructing biomimetic environments by immobilizing a collagen-derived high-affinity cell-binding peptide P-15 in three-dimensional (3-D) templates. The cell-binding peptide can be expected to transduce mechanical forces. In their physiological environment, periodontal ligament fibroblasts (PDLF) are subject to significant mechanical forces. We have examined the behavior of human PDLF in culture on particulate bovine anorganic bone mineral (ABM) coated with P-15 (ABM-P-15). Greater numbers of cells associated with ABM-P-15 compared to ABM alone. Higher levels of incorporation of radiolabeled precursors in DNA and protein were consistent with the presence of larger numbers of cells on ABM-P-15 compared to ABM cultures. Scanning electron microscopic examination showed that cultures on ABM-P-15 generated highly oriented 3-D colonies of elongated cells and formed copious amounts of fibrous as well as membranous matrix reminiscent of ligamentous structures. PDLF cultured on ABM formed sparse monolayers with little order and a meager matrix. Alizarin Red stained the matrix of particle associated cells and inter-particle cellular bridges in P-15-associated cultures, indicating mineralization. 3-D colony formation and ordering of cells along with increased mineralization suggests that the coupling of cells to the ABM matrix through P-15 may provide a biomimetic environment permissive for cell differentiation and morphogenesis. Our studies suggest that ABM-P-15 templates may be effective as endosseous grafts, and, when seeded with PDLF, these matrices may serve as tissue engineered substitutes for autologous bone grafts.
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26 |
144 |
16
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Shakya M, Colin-Jones R, Theiss-Nyland K, Voysey M, Pant D, Smith N, Liu X, Tonks S, Mazur O, Farooq YG, Clarke J, Hill J, Adhikari A, Dongol S, Karkey A, Bajracharya B, Kelly S, Gurung M, Baker S, Neuzil KM, Shrestha S, Basnyat B, Pollard AJ. Phase 3 Efficacy Analysis of a Typhoid Conjugate Vaccine Trial in Nepal. N Engl J Med 2019; 381:2209-2218. [PMID: 31800986 PMCID: PMC6785806 DOI: 10.1056/nejmoa1905047] [Citation(s) in RCA: 136] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Salmonella Typhi is a major cause of fever in children in low- and middle-income countries. A typhoid conjugate vaccine (TCV) that was recently prequalified by the World Health Organization was shown to be efficacious in a human challenge model, but data from efficacy trials in areas where typhoid is endemic are lacking. METHODS In this phase 3, randomized, controlled trial in Lalitpur, Nepal, in which both the participants and observers were unaware of the trial-group assignments, we randomly assigned children who were between 9 months and 16 years of age, in a 1:1 ratio, to receive either a TCV or a capsular group A meningococcal conjugate vaccine (MenA) as a control. The primary outcome was typhoid fever confirmed by blood culture. We present the prespecified analysis of the primary and main secondary outcomes (including an immunogenicity subgroup); the 2-year trial follow-up is ongoing. RESULTS A total of 10,005 participants received the TCV and 10,014 received the MenA vaccine. Blood culture-confirmed typhoid fever occurred in 7 participants who received TCV (79 cases per 100,000 person-years) and in 38 who received MenA vaccine (428 cases per 100,000 person-years) (vaccine efficacy, 81.6%; 95% confidence interval, 58.8 to 91.8; P<0.001). A total of 132 serious adverse events (61 in the TCV group and 71 in the MenA vaccine group) occurred in the first 6 months, and 1 event (pyrexia) was identified as being vaccine-related; the participant remained unaware of the trial-group assignment. Similar rates of adverse events were noted in the two trial groups; fever developed in 5.0% of participants in the TCV group and 5.4% in the MenA vaccine group in the first week after vaccination. In the immunogenicity subgroup, seroconversion (a Vi IgG level that at least quadrupled 28 days after vaccination) was 99% in the TCV group (677 of 683 participants) and 2% in the MenA vaccine group (8 of 380 participants). CONCLUSIONS A single dose of TCV was immunogenic and effective in reducing S. Typhi bacteremia in children 9 months to 16 years of age. (Funded by the Bill and Melinda Gates Foundation; Current Controlled Trials number, ISRCTN43385161.).
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Clinical Trial, Phase III |
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136 |
17
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Faulk WP, Temple A, Lovins RE, Smith N. Antigens of human trophoblasts: a working hypothesis for their role in normal and abnormal pregnancies. Proc Natl Acad Sci U S A 1978; 75:1947-51. [PMID: 273921 PMCID: PMC392459 DOI: 10.1073/pnas.75.4.1947] [Citation(s) in RCA: 128] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
This report describes the preparation and characterization of antisera to human trophoblast membranes. Rabbit antisera were raised to trophoblast microvilli prepared by differential ultracentrifugation. Antibodies to serum proteins were removed by solid-phase immunoabsorption with normal human serum, and indirect immunofluorescence experiments with cryostat sections of human placentas showed that the absorbed anti-trophoblast sera reacted with trophoblasts as well as with stromal cells and endothelium of chorionic villi. The antisera also produced membrane fluorescence when studied on viable lymphocytes and certain human cell lines. These anti-trophoblast sera were also lymphocytotoxic, and this reaction was abolished by prior absorption of the antisera with leukocytes. The leukocyte-absorbed anti-trophoblast sera retained their ability to react with trophoblasts and certain human cell lines, but no longer reacted with lymphocytes or placental stromal cells and endothelium. Two categories of trophoblast membrane antigens are thus defined: one present on trophoblasts and certain human cells lines (tentatively designated TA(1)), and the other on trophoblasts and lymphocytes, villous fibroblasts, and endothelium (tentatively designated TA(2)). A working hypothesis is proposed stating that normal pregnancy involves the generation of anti-TA(2) subsequent to blastocyst implantation and entrance of trophoblasts into the maternal circulation. This involves a mechanism similar to allogeneic cell stimulation and results in antibodies that block either the recognition or cytotoxicity of TA(1). Failure to mount this response allows TA(1) recognition and trophoblast immunopathology. Experimental and clinical studies in support of this working hypothesis, particularly involving abortion and toxemia, are cited from published reports.
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research-article |
47 |
128 |
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Acree F, Turner RB, Gouck HK, Beroza M, Smith N. L-Lactic acid: a mosquito attractant isolated from humans. Science 1968; 161:1346-7. [PMID: 5673445 DOI: 10.1126/science.161.3848.1346] [Citation(s) in RCA: 125] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
L-Lactic acid was the major component in material isolated from humans that was active as an attractant for female yellow fever mosquitoes, Aedes aegypti (L.). The L(+)-isomer was several times as attractive as the D-isomer. Good correlation was found between the attractiveness of an individual to mosquitoes and the quantity of lactic acid present in an acetone washing of his hand.
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57 |
125 |
19
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Smith NF, Marsh S, Scott-Horton TJ, Hamada A, Mielke S, Mross K, Figg WD, Verweij J, McLeod HL, Sparreboom A. Variants in the SLCO1B3 Gene: Interethnic Distribution and Association with Paclitaxel Pharmacokinetics. Clin Pharmacol Ther 2007; 81:76-82. [PMID: 17186002 DOI: 10.1038/sj.clpt.6100011] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
To explore retrospectively the relationships between paclitaxel pharmacokinetics and three known, non-synonymous single-nucleotide polymorphisms (SNPs) in SLCO1B3, the gene encoding organic anion transporting polypeptide (OATP)1B3. Accumulation of [(3)H]paclitaxel was studied in Xenopus laevis oocytes injected with cRNA of Oatp1b2, OATP1A2, OATP1B1, OATP1B3, OAT1, OAT3, OCT1, and NTCP. The 334T>G (Ser112Ala), 699G>A (Met233Ile), and 1564G>T (Gly522Cys) loci of SLCO1B3 were screened in 475 individuals from five ethnic groups and 90 European Caucasian cancer patients treated with paclitaxel. Only OATP1B3 was capable of transporting paclitaxel to a significant extent (P=0.003). The 334T>G and 699G>A SNPs were less common in the African-American and Ghanaian populations (P<0.000001). Paclitaxel pharmacokinetics were not associated with the studied SNPs or haplotypes (P>0.3). The studied SNPs in SLCO1B3 appear to play a limited role in the disposition of paclitaxel, although their clinical significance in other ethnic populations remains to be investigated.
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125 |
20
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Fletcher CD, Evans BJ, MacArtney JC, Smith N, Wilson Jones E, McKee PH. Dermatofibrosarcoma protuberans: a clinicopathological and immunohistochemical study with a review of the literature. Histopathology 1985; 9:921-38. [PMID: 3840767 DOI: 10.1111/j.1365-2559.1985.tb02878.x] [Citation(s) in RCA: 124] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Forty-one cases of dermatofibrosarcoma protuberans are presented. The clinical features and histopathological appearances are described. Immunohistochemical staining of thirteen cases with antisera to lysozyme, alpha 1-antichymotrypsin and S-100 protein has provided no evidence to support either a histiocytic or neuroectodermal origin for these tumours. In reviewing the literature, the histogenetic origin, differential diagnosis and malignant potential of dermatofibrosarcoma protuberans are discussed.
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40 |
124 |
21
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Gill P, Dowell AC, Neal RD, Smith N, Heywood P, Wilson AE. Evidence based general practice: a retrospective study of interventions in one training practice. BMJ (CLINICAL RESEARCH ED.) 1996; 312:819-21. [PMID: 8608291 PMCID: PMC2350715 DOI: 10.1136/bmj.312.7034.819] [Citation(s) in RCA: 123] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVES To estimate the proportion of interventions in general practice that are based on evidence from clinical trials and to assess the appropriateness of such an evaluation. DESIGN Retrospective review of case notes. SETTING One suburban training general practice. SUBJECTS 122 consecutive doctor-patient consultations over two days. MAIN OUTCOME MEASURES Proportions of interventions based on randomised controlled trials (from literature search with Medline, pharmaceutical databases, and standard textbooks), on convincing non-experimental evidence, and without substantial evidence. RESULTS 21 of the 122 consultations recorded were excluded due to insufficient data; 31 of the interventions were based on randomised controlled trial evidence and 51 based on convincing non-experimental evidence. Hence 82/101 (81%) of interventions were based on evidence meeting our criteria. CONCLUSIONS Most interventions within general practice are based on evidence from clinical trials, but the methods used in such trials may not be the most appropriate to apply to this setting.
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research-article |
29 |
123 |
22
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Pallonen UE, Prochaska JO, Velicer WF, Prokhorov AV, Smith NF. Stages of acquisition and cessation for adolescent smoking: an empirical integration. Addict Behav 1998; 23:303-24. [PMID: 9668929 DOI: 10.1016/s0306-4603(97)00074-9] [Citation(s) in RCA: 121] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Adolescent cigarette smoking acquisition and cessation were integrated into a single nine-stages-of-change continuum using the transtheoretical model of change framework. Findings in a high school student sample (n > 700) showed that a few of the never smokers were planning to try smoking, and half of the current smokers were contemplating quitting. More than half of former smokers were long-term quitters. The high pros of smoking scores assessing coping benefits of cigarettes were related to smoking acquisition and the high con (disadvantages) scores to long-term abstinence. Never smokers were most tempted to try smoking when they anticipated that smoking would help reduce negative and increase positive mood. Current and former smokers were tempted due to peer cigarette offers and negative mood. These temptations were significantly reduced among ex-smokers.
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27 |
121 |
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Bousquet J, Siergiejko Z, Swiebocka E, Humbert M, Rabe KF, Smith N, Leo J, Peckitt C, Maykut R, Peachey G. Persistency of response to omalizumab therapy in severe allergic (IgE-mediated) asthma. Allergy 2011; 66:671-8. [PMID: 21255035 DOI: 10.1111/j.1398-9995.2010.02522.x] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND The physician's global evaluation of treatment effectiveness (GETE) at 16 weeks has been shown to be the most effective assessment of response to omalizumab (XOLAIR®). This randomized, open-label, parallel-group study evaluated the persistency of treatment responder classification in patients receiving omalizumab added to optimized asthma therapy (OAT). METHODS Patients (12-75 years, n = 400) with severe allergic asthma, uncontrolled despite Global Initiative for Asthma 2004 Step 4 therapy, received OAT and omalizumab (n = 272) or OAT (n = 128) for 32 weeks. Response or nonresponse was evaluated at Weeks 16 and 32. Response was defined as an investigator's (physician's) GETE rating of excellent or good; nonresponse was defined as a rating of moderate, poor or worsening. RESULTS Three hundred and forty-nine patients had GETE ratings available at Weeks 16 and 32 (omalizumab n = 258, OAT n = 91). Omalizumab responders of about 171/187 (91.4%)and 44/71 (62.0%) omalizumab nonresponders at Week 16 persisted as responders or nonresponders at Week 32. The investigator's GETE at Week 16 predicted persistency of response or nonresponse to omalizumab at Week 32 for 83.3% (215/258) of patients. OAT patients showed a lower persistency of response (18/28 [64.3%]) and a higher persistency of nonresponse (57/63 [90.5%]) than omalizumab patients. Excellent and good GETE ratings in omalizumab-treated patients were reflected by improvements in exacerbation rates (P < 0.001), severe exacerbation rates (P = 0.023), hospitalizations (P = 0.003), total emergency visits (P = 0.026) and Asthma Control Questionnaire overall score (P < 0.001). CONCLUSION Response to omalizumab, as assessed by a physician's GETE at 16 weeks, is an effective predictor of continuing persistent response to omalizumab for the majority of patients.
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Randomized Controlled Trial |
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120 |
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Watson C, Whittaker S, Smith N, Vora AJ, Dumonde DC, Brown KA. IL-6 acts on endothelial cells to preferentially increase their adherence for lymphocytes. Clin Exp Immunol 1996; 105:112-9. [PMID: 8697617 PMCID: PMC2200481 DOI: 10.1046/j.1365-2249.1996.d01-717.x] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Using a quantitative monolayer adhesion assay, the current report shows that treatment of human umbilical vein endothelial cells (HUVEC) with IL-6 increases their adhesiveness for blood lymphocytes, particularly CD4+ cells, but not for polymorphonuclear cells and monocytes. This effect, which was most pronounced when using low concentrations of the cytokine (0.1-1.0 U/ml) and a short incubation period (4h), was also apparent with microvascular endothelial cells and a hybrid endothelial cell line. Skin lesions from patients with mycosis fungoides contain high levels of IL-6, and blood lymphocytes from patients with this disorder also exhibited an enhanced adhesion to IL-6-treated HUVEC. The cytokine enhanced intercellular adhesion molecule-1 (ICAM-1) expression and induced the expression of vascular cell adhesion molecule-1 (VCAM-1) and E-selectin on endothelial cells. Antibody blocking studies demonstrated that the vascular adhesion molecules ICAM-1, VCAM-1 and E-selectin and the leucocyte integrin LFA-1 all contributed to lymphocyte binding to endothelium activated by IL-6. It is proposed that IL-6 may be involved in the recruitment of lymphocytes into non-lymphoid tissue.
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other |
29 |
119 |
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Smith NF, Figg WD, Sparreboom A. Role of the liver-specific transporters OATP1B1 and OATP1B3 in governing drug elimination. Expert Opin Drug Metab Toxicol 2006; 1:429-45. [PMID: 16863454 DOI: 10.1517/17425255.1.3.429] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Members of the organic anion transporting polypeptide (OATP) family are responsible for the cellular uptake of a broad range of endogenous compounds and xenobiotics in multiple tissues. This review focuses on OATP1B1 and -1B3, which are specifically expressed in the liver and considered to be of particular importance for hepatic drug elimination and drug pharmacokinetics. Recent literature has indicated that inhibition of these transporters may result in drug-drug interactions. Furthermore, genetic polymorphisms in the genes encoding OATP1B1 and -1B3 have been described that increase or decrease transport in vitro and in vivo. Alteration of transporter function by either of these mechanisms may contribute to interindividual variability in drug disposition and response. In this review an update of this rapidly emerging field is provided.
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Review |
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118 |