326
|
Zhang M, Roberts C. Comparison of computational analysis with clinical measurement of stresses on below-knee residual limb in a prosthetic socket. Med Eng Phys 2000; 22:607-12. [PMID: 11259929 DOI: 10.1016/s1350-4533(00)00079-5] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Interface pressures and shear stresses between a below-knee residual limb and prosthetic socket predicted using finite element analyses were compared with experimental measurements. A three-dimensional nonlinear finite element model, based on actual residual geometry and incorporating PTB socket rectification and interfacial friction/slip conditions, was developed to predict the stress distribution. A system for measuring pressures and bi-axial shear stresses was used to measure the stresses in the PTB socket of a trans-tibial amputee. The FE-predicted results indicated that the peak pressure of 226 kPa occurred at the patellar tendon area and the peak shear stress of 50 kPa at the anterolateral tibia area. Quantitatively, FE-predicted pressures were 11%, on average, lower than those measured by triaxial transducers placed at all the measurement sites. Because friction/slip conditions between the residual limb and socket liner were taken into consideration by using interface elements in the FE model, the directions and magnitudes of shear stresses match well between the FE prediction and clinical measurements. The results suggest that the nonlinear mechanical properties of soft tissues and dynamic effects during gait should be addressed in future work.
Collapse
|
327
|
Yamada K, Elliott WM, Hayashi S, Brattsand R, Roberts C, Vitalis TZ, Hogg JC. Latent adenoviral infection modifies the steroid response in allergic lung inflammation. J Allergy Clin Immunol 2000; 106:844-51. [PMID: 11080705 DOI: 10.1067/mai.2000.110473] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Steroid-resistant asthma develops after adenoviral bronchiolitis. OBJECTIVE We sought to determine the effect of steroids on allergic lung inflammation in the presence of latent adenoviral infection. METHODS Guinea pigs with latent adenoviral (n = 12) or sham (n = 12) infections were sensitized and challenged with ovalbumin (OA) or sham sensitized and challenged with saline solution. The effect of steroids (20 mg/kg administered intraperitoneally) on OA-induced lung inflammation was examined by using quantitative histology as the outcome measure. RESULTS Latent adenoviral infection increased CD8(+) cells in the airway wall and CD8(+) cells, macrophages, B cells, and CD4(+) cells in the lung parenchyma. Ovalbumin challenge, on the other hand, increased eosinophils, macrophages, B cells, and CD4(+) cells in both the airway wall and lung parenchyma independent of the effect of latent adenoviral infection. In the sham-infected groups steroid treatment caused the expected reduction in the eosinophilic infiltrate induced by OA challenge in the airways without affecting the other cells. In the presence of both latent adenoviral infection and OA challenge, steroid treatment had no effect on allergen-induced eosinophilia but reduced CD8(+) cells in the airways and CD8(+) cells, CD4(+) cells, and B cells in the parenchyma. CONCLUSION Latent adenoviral infection and OA challenge result in different types of lung inflammation, and the presence of latent adenoviral infection causes OA-induced eosinophilic airway inflammation to become steroid resistant.
Collapse
|
328
|
Reddy T, Szczotka LB, Roberts C. Peripheral corneal contour measured by topography influences soft toric contact lens fitting success. THE CLAO JOURNAL : OFFICIAL PUBLICATION OF THE CONTACT LENS ASSOCIATION OF OPHTHALMOLOGISTS, INC 2000; 26:180-5. [PMID: 11071341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
PURPOSE Empirical fitting success is important to expanding the soft toric contact lens market. Previous study has lead to the hypothesis that lens flexure may alter expected fitting relationships and back vertex power (BVP) in situ. In this study, baseline topographic features as potential variables in predicting soft toric fitting success were analyzed. METHODS One-hundred forty-nine eyes were empirically fit with back surface toric soft lenses after placido-based videokeratography was performed. Measurements recorded from baseline instantaneous maps included: flat simulated keratometry (Sim-K) value (in diopters) and axis, steep Sim-K value (in diopters) and axis, eccentricity of the flat meridian, and the form of corneal astigmatism. Astigmatism was classified as types I-V based upon differences between central and peripheral corneal toricity. RESULTS Ninety-three of 149 (62.4%) eyes were successfully fit empirically with the first trial lens. One-hundred thirty-five of 149 (90.6%) eyes were ultimately successful after unsuccessful trial lenses were adjusted and reordered. There were no differences between the empirically fit success and failure groups in instrument reported eccentricity, Sim-K values, or Sim-K axes (P>0.05). Of 115 eyes classified for form of corneal astigmatism, 76 (66%) were classified with high or irregular peripheral astigmatism (types IV and V). There was a significant association between fitting success and the form of corneal toricity (P=0.0327). Thirty-nine of 115 (34%) eyes were classified as corneal types I-III (spherical or minimally toric corneal periphery) and were associated with empirical fitting success (P=0.0092). CONCLUSION Empirical soft toric fitting success can be anticipated in spherical corneas, central astigmatism, or corneas with peripheral toricity which matches the central toricity. However, high and irregular peripheral corneal toricity occurs in the majority of astigmatic patients. Corneal topography is a valuable tool to assess peripheral astigmatism which may be one factor influencing unexpected lens performance.
Collapse
|
329
|
|
330
|
Roberts C. ADAA's answers to the most frequently asked questions about dental assisting professionalism. Interview by Jennifer Blake. DENTAL ASSISTANT (CHICAGO, ILL. : 1994) 2000; 69:4, 6. [PMID: 11218476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
|
331
|
|
332
|
Roberts C, Hatcher P, Hagan JJ, Austin NE, Jeffrey P, Wyman P, Gaster LM, Routledge C, Middlemiss DN. The effect of SB-236057-A, a selective 5-HT1B receptor inverse agonist, on in vivo extracellular 5-HT levels in the freely-moving guinea-pig. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2000; 362:177-83. [PMID: 10961381 DOI: 10.1007/s002100000276] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
5-HT1B autoreceptors are involved in the control of extracellular 5-HT levels from both the terminal and cell body regions of serotonergic neurones. In this study we report on the effect of a selective and potent 5-HT1B receptor inverse agonist, SB-236057-A (1'-ethyl-5-(2'-methyl-4'-(5-methyl- 1,3,4-oxadiazolyl-2-yl)biphenyl-4-carbonyl)-2,3,6,7-tetrahydros piro [furo[2,3-f]indole-3,4' -piperidine] hydrochloride), on extracellular 5-HT levels in the cortex and dentate gyrus of the freely-moving guinea-pig, using the technique of in vivo microdialysis. SB-236057-A had ca. 23% bioavailability following oral drug administration. In vivo hypothermia pharmacodynamic assays demonstrated it was brain penetrant with a duration of action in excess of 18 h. SB-236057-A (0.75 mg/kg p.o.) increased extracellular 5-HT levels in the dentate gyrus to a maximum of 167+/-7% of basal but had no effect in the frontal cortex. However, a small increase in cortical 5-HT levels (117+11% of basal) was evident at 2.5 mg/kg p.o. In addition, SB-236057-A (0.75 mg/kg and 2.5 mg/kg p.o.) antagonised the sumatriptan-induced inhibition of extracellular 5-HT levels in the guinea-pig frontal cortex. These differences were attributed to MRN-innervated regions (e.g. dentate gyrus) being more responsive to 5-HT1B receptor-mediated negative feedback than DRN-innervated regions (e.g. frontal cortex). In the dentate gyrus, the increase in 5-HT release induced by SB-236057-A (0.75 mg/kg p.o.) was comparable to that after 14 days of paroxetine (10 mg/kg p.o.) administration, reaching a maximum of 183+/-13% of basal. These data suggest that acute 5-HT1B receptor blockade, by virtue of increased 5-HT release in the dentate gyrus, may provide a rapidly acting antidepressant.
Collapse
|
333
|
Gonik B, Jones T, Contreras D, Fasano N, Roberts C. The obstetrician-gynecologist's role in vaccine-preventable diseases and immunization. Obstet Gynecol 2000; 96:81-4. [PMID: 10862847 DOI: 10.1016/s0029-7844(00)00860-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To assess by survey the immunization role currently played obstetrician-gynecologists in the state of Michigan. METHODS Masked questionnaires requesting demographic, knowledge-based, practice, and attitudinal data were sent to 850 ACOG-registered fellows. RESULTS Three hundred sixty-five physicians responded, 313 of whom were in active practice. Most were male (70%) and graduated from medical school between 1970 and 1989 (68%). The majority provided both obstetric and gynecologic services. The minority (47%) specifically identified themselves as primary care providers. Only 15% of respondents considered screening for vaccine-preventable diseases to be outside the realm of routine obstetric-gynecologic care. In practice, however, 19% did not screen their obstetric patients for any vaccine-preventable diseases, and only 10% assessed their patients for all nine vaccine-preventable diseases listed in the questionnaire. In gynecologic patients, almost 40% of physicians did not assess for any vaccine-preventable disease. A wide range in knowledge level was identified concerning vaccine-preventable diseases, immunization recommendations, and vaccine safety. CONCLUSION These data show a discrepancy between perceived responsibilities and actual practice patterns of obstetrician-gynecologists regarding vaccine-preventable diseases and the immunization of women. Limitations in current knowledge and practical concerns specific to vaccine administration contribute to this disparity.
Collapse
|
334
|
Edwards SL, Roberts C, McKean ME, Cockburn JS, Jeffrey RR, Kerr KM. Preoperative histological classification of primary lung cancer: accuracy of diagnosis and use of the non-small cell category. J Clin Pathol 2000; 53:537-40. [PMID: 10961178 PMCID: PMC1731233 DOI: 10.1136/jcp.53.7.537] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIMS To compare the preoperative classification of lung carcinoma made on cytological and histological specimens with the postoperative classification made on the resected specimen. In addition, to find out how often the term "non-small cell lung cancer, not otherwise specified" (NSCLC) was used, and in such cases to note the final diagnosis. METHODS Between 1991 and 1995, 303 patients had a lung resection in Aberdeen for primary carcinoma. For each patient, the departmental records were examined for preoperative specimens (cytological and histological). A note was made of whether each specimen was positive or negative for malignancy and, if positive, what the cell type was. Where patients had more than one sample submitted, the most specific result was taken. RESULTS Fifty four per cent of patients had a correct specific preoperative diagnosis of malignancy, whereas 34% were labelled as NSCLC. Patients with squamous carcinoma were more likely to have a diagnosis of malignancy (88%) that was specifically correct (75%). Patients who had adenocarcinoma were less likely to have a preoperative diagnosis of malignancy (64%) that was specifically correct (35%). For those in whom a diagnosis of NSCLC was made, 55% turned out to have adenocarcinoma whereas 24% had squamous carcinoma. CONCLUSIONS By adhering strictly to criteria, a high accuracy of diagnosis can be achieved for squamous carcinoma, but the diagnosis of adenocarcinoma seems to be more of a challenge. NSCLC is a useful and appropriate classification, the use of which reduces the rate of inaccurate specific diagnosis. There are occasions when pathologists can provide a more accurate diagnosis by being less precise.
Collapse
|
335
|
|
336
|
Cohen J, Roberts C. A new joint training programme in infectious diseases and medical microbiology. JOURNAL OF THE ROYAL COLLEGE OF PHYSICIANS OF LONDON 2000; 34:363-5. [PMID: 11005074 PMCID: PMC9665474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The increasing overlap between the disciplines of medical microbiology and infectious diseases prompted the Joint Royal Colleges Committee on Infection and Tropical Medicine to set up a working party to examine how trainees could obtain certification in both subjects. Following widespread consultations, a scheme was developed that entails six years of training and leads to the award of CCSTs in both microbiology and infectious diseases. Both Royal Colleges and the Specialist Training Authority have approved the scheme. Joint training will be demanding and will not be suitable for everyone; it represents an alternative approach to training in the infection disciplines that will run alongside the existing monospecialty training programmes.
Collapse
|
337
|
Ebert DW, Roberts C. In vitro frog sciatic nerve as a peripheral nerve model for studies of the mechanism of action of low energy lasers: Part one. Lasers Surg Med 2000; 21:32-41. [PMID: 9228638 DOI: 10.1002/(sici)1096-9101(1997)21:1<32::aid-lsm6>3.0.co;2-z] [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: 02/04/2023]
Abstract
BACKGROUND AND OBJECTIVE There have been numerous reports of modulation of peripheral nerve action potential characteristics through application of low energy laser irradiation (LELI), although no mechanism has yet been advanced to explain these observations. In order to investigate the mechanism of LELI effects in peripheral nerve tissue, a well-characterized, reliable, and robust peripheral nerve preparation is required. The objective of this study was to evaluate the in vitro frog sciatic nerve as a candidate model for future LELI mechanism studies. MATERIALS AND METHODS Following 60-minute baseline recordings of compound action potential (CAP) amplitude, latency, depolarization rate, and repolarization rate, helium-neon (HeNe) laser irradiation (632 nm, 15 min, 1-7 J, 44-320 J/cm2) was delivered to one of two sites on the nerve. Laser-induced changes in CAP parameters were analyzed during irradiation and for 60 minutes post-irradiation using a repeated measures linear regression model. RESULTS In the treatment group that received 7 J of HeNe energy over the recording electrode, CAP latency increased relative to nonirradiated controls during the postirradiation period. No other treatment group demonstrated laser-induced changes in CAP characteristics at any time during the experiment. CONCLUSION HeNe irradiation demonstrated limited ability to alter the CAP under these conditions. As such, the in vitro frog sciatic nerve is an inappropriate model for mechanism of action studies.
Collapse
|
338
|
Abstract
Revision surgery of cemented implants is indicated when mechanical failure causes severe pain and/or loss of function for the patient. Successful revision arthroplasty of cemented implants requires complete removal of the existing cement. Removal of old cement is an arduous task often causing damage to the surrounding bone tissue. In this study, the authors investigate the use of an Argon laser and the addition of dyes to enhance the laser ablation of bone cement. Methylene blue and red dye #13 were each added separately to polymethylmethacrylate (PMMA) bone cement powder. A continuous wave Argon ion laser (lambda = 514 nm) was used for cement ablation. Cement samples were ablated at different power levels (1.5, 2.3, and 3.0 W) and exposure times (30, 60, 90, 120 sec). The results show that the Argon laser was unable to ablate undyed PMMA. However, the addition of either methylene blue or red dye #13 greatly improved cement ablation by altering the cements' absorption characteristics. Results of Student's t-tests show a statistical difference between red and blue dyed PMMA mean ablation areas at all energy levels tested (P < .0002). As expected, all red ablation areas were greater than blue ablation areas at each energy level tested since red dye absorbs more energy at 514 nm than methylene blue dye. The results of this study suggest that by selectively altering the absorption characteristics of PMMA, laser removal of bone cement can be achieved. In addition, this study also shows that bone tissue does not absorb visible light energy at 514 nm, suggesting that bone cement may be removed with minimal damage to the surrounding bone tissue.
Collapse
|
339
|
Abstract
BACKGROUND AND OBJECTIVE Numerous authors have reported successful alteration of peripheral nerve action potential characteristics through application of low energy laser irradiation (LELI). The statistical analysis that accompanies many of these reports frequently does not account for the special nature of the data generated in typical LELI experiments. The objective of this study was to evaluate the application of repeated measures linear regression techniques to the analysis of this type of data. Issues of analyzing raw versus normalized data, proper accounting for correlation between measurements, and discrete time point hypothesis testing were addressed. STUDY DESIGN/MATERIALS AND METHODS The data analyzed in this work were generated from an experiment in which in vitro frog sciatic nerves were irradiated with a helium-neon laser using a variety of treatment protocols. Compound action potential (CAP) amplitude, latency, depolarization rate, and repolarization rate were recorded at 1-minute intervals for 135 minutes for each nerve. Laser-induced changes in CAP parameters were analyzed using various repeated measures linear regression models. RESULTS The findings of statistical significance were highly dependent on the rigor of the regression model applied. Application of the same regression model to raw and normalized data produced different findings of significance. Determination of significant contrasts was highly dependent on how well the regression model accounted for the correlation between repeated measurements made on the same nerve. In general, models that failed to account adequately for this correlation produced more findings of significant contrasts than increasingly rigorous models. Finally, discrete time point hypothesis testing on normalized data can suggest improper statistical conclusions if the proper correlation structure is not applied to the data set. CONCLUSION Linear regression analysis offers advantages over discrete time point hypothesis testing in the analysis of highly correlated serial data of this type. Trends in the behavior of the measured parameters are evident, rigorous accounting for correlation between measurements is facilitated, and hypothesis testing is highly flexible.
Collapse
|
340
|
Dimopoulos G, Casavant TL, Chang S, Scheetz T, Roberts C, Donohue M, Schultz J, Benes V, Bork P, Ansorge W, Soares MB, Kafatos FC. Anopheles gambiae pilot gene discovery project: identification of mosquito innate immunity genes from expressed sequence tags generated from immune-competent cell lines. Proc Natl Acad Sci U S A 2000; 97:6619-24. [PMID: 10841561 PMCID: PMC18678 DOI: 10.1073/pnas.97.12.6619] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Together with AIDS and tuberculosis, malaria is at the top of the list of devastating infectious diseases. However, molecular genetic studies of its major vector, Anopheles gambiae, are still quite limited. We have conducted a pilot gene discovery project to accelerate progress in the molecular analysis of vector biology, with emphasis on the mosquito's antimalarial immune defense. A total of 5,925 expressed sequence tags were determined from normalized cDNA libraries derived from immune-responsive hemocyte-like cell lines. The 3,242 expressed sequence tag-containing cDNA clones were grouped into 2,380 clone clusters, potentially representing unique genes. Of these, 1,118 showed similarities to known genes from other organisms, but only 27 were identical to previously known mosquito genes. We identified 38 candidate genes, based on sequence similarity, that may be implicated in immune reactions including antimalarial defense; 19 of these were shown experimentally to be inducible by bacterial challenge, lending support to their proposed involvement in mosquito immunity.
Collapse
|
341
|
Esmail A, Quayle JA, Roberts C. Assessing the appropriateness of paediatric hospital admissions in the United Kingdom. JOURNAL OF PUBLIC HEALTH MEDICINE 2000; 22:231-8. [PMID: 10912565 DOI: 10.1093/pubmed/22.2.231] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND In order to assess whether the documented rise in paediatric admissions was due to inappropriate admissions, an objective measure of the appropriateness of paediatric admissions, modified for use in the United Kingdom, was used to measure the level of inappropriate admissions. The relationship of appropriateness of admissions to age, gender, time of admission and source of referral was investigated. METHODS A retrospective review was carried out of a sample of paediatric records in 13 NHS district general hospitals in South Eastern England between April 1990 and March 1991 using the Paediatric Appropriateness Evaluation Protocol (PAEP) modified for use in the United Kingdom. RESULTS A total of 3,324 paediatric admissions in 13 hospitals were assessed. Eight per cent of the sampled admissions were inappropriate. Age [odds ratio (OR)=0.87], gender (OR = 1.39) and weekend admissions (OR = 1.42) were associated with inappropriate admissions. After controlling for these factors, there was no significant variation between hospitals. CONCLUSION The low level of inappropriate admissions may be a reflection of well-developed primary care services in the United Kingdom. Alternatives to hospital admission for the assessment of minor self-limiting illness in young children may have a role in reducing inappropriate admissions.
Collapse
|
342
|
Koozekanani D, Roberts C, Katz SE, Herderick EE. Intersession repeatability of macular thickness measurements with the Humphrey 2000 OCT. Invest Ophthalmol Vis Sci 2000; 41:1486-91. [PMID: 10798667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
PURPOSE This study was designed to determine intersession repeatability of measurements of macular thickness made with a commercially available optical coherence tomography (OCT) system. The images that can be routinely acquired with the commercial instrument differ significantly in quality from the images in the literature, which have mostly been acquired on prototype systems. METHODS Multiple OCT images of the nasal macula were obtained from the right eye during three independent measuring sessions, using the Humphrey 2000 OCT system (Humphrey, San Leandro, CA). Twenty-six volunteers with no history of ocular disease participated in this investigation. Eyes in all subjects were undilated during scan acquisition. Scans were horizontal, 3 mm long, and through the fovea. Five scans were used from each session, for a total of 15 scans per subject. Retinal boundaries were automatically detected using custom software. Statistical software was used to calculate intersession and intrasession repeatability. Manual correction was performed on the automatically detected boundaries, and a second analysis was performed using these boundaries. RESULTS When no manual correction of boundaries was performed, there were no significant effects between different sessions (P = 0.529) or between different scans within the same session (P = 0.509). Average retinal thickness was found to be 274 +/- 17 microm for a 1-mm long region 0.75 mm from the fovea. Individual scan averages differed from overall patient averages by 0 +/- 4.3 microm (99% confidence interval, 11.2 microm). CONCLUSIONS OCT measurements of macular thickness made with the Humphrey 2000 OCT system are repeatable over different sessions with an expected variation of less than 11 microm (99% confidence interval).
Collapse
|
343
|
Roberts C, Bond B, White IR, Herdon HJ. Solubilisation of a novel anticonvulsant binding site from pig cortical membranes. J Recept Signal Transduct Res 2000; 20:167-86. [PMID: 10994652 DOI: 10.3109/10799890009150643] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The present study describes the solubilisation of the novel anticonvulsant, SB-204269, binding site from pig cortical membranes. Throughout the study the binding of a close analogue of this compound, [125I]-SB-217644 (trans 6- Acetyl-4S-(3-iodobenzoylamino)-3,4-dihydro-2,2-dimethyl-2H-benzo[b ]pyran-3R-ol) was used to monitor the success of the solubilisation procedure. [125I]-SB-217644 was an ideal mechanistic tool for quantifying the binding to this novel anticonvulsant site, with a high specific activity and affinity (K(D) of 3 nmol/l). Optimum conditions for the solubilisation of this anticonvulsant binding site were investigated using a multifactorial experimental design to assess a large number of variables. Detergent type, detergent-protein ratio, absence of Mg2+ and temperature were deemed to be important factors. However, the increases observed in binding site specific activity were minimal compared with those achieved for yields. Maximum percentage yields of binding activity (25%) were achieved with a low concentration of the zwitterionic detergent, CHAPS, in the presence of a low protein concentration. This yield was further enhanced on combining mixtures of detergents. The highest recovery (37%) was achieved with a 50:50 (v:v; 1.5 x critical micelle concentration) mixture of the ionic detergent, sodium cholate, and the non-ionic detergent, MEGA-10. In summary, we report the successful solubilisation of a novel anticonvulsant binding site, identified by its selective affinity for SB-204269 and its analogues. The recovery of nearly 40% of the target binding sites from the starting material should provide a good starting point for the purification of this protein.
Collapse
|
344
|
Venning P, Durie A, Roland M, Roberts C, Leese B. Randomised controlled trial comparing cost effectiveness of general practitioners and nurse practitioners in primary care. BMJ (CLINICAL RESEARCH ED.) 2000; 320:1048-53. [PMID: 10764367 PMCID: PMC27348 DOI: 10.1136/bmj.320.7241.1048] [Citation(s) in RCA: 285] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To compare the cost effectiveness of general practitioners and nurse practitioners as first point of contact in primary care. DESIGN Multicentre randomised controlled trial of patients requesting an appointment the same day. SETTING 20 general practices in England and Wales. PARTICIPANTS 1716 patients were eligible for randomisation, of whom 1316 agreed to randomisation and 1303 subsequently attended the clinic. Data were available for analysis on 1292 patients (651 general practitioner consultations and 641 nurse practitioner consultations). MAIN OUTCOME MEASURES Consultation process (length of consultation, examinations, prescriptions, referrals), patient satisfaction, health status, return clinic visits over two weeks, and costs. RESULTS Nurse practitioner consultations were significantly longer than those of the general practitioners (11.57 v 7.28 min; adjusted difference 4. 20, 95% confidence interval 2.98 to 5.41), and nurses carried out more tests (8.7% v 5.6% of patients; odds ratio 1.66, 95% confidence interval 1.04 to 2.66) and asked patients to return more often (37. 2% v 24.8%; 1.93, 1.36 to 2.73). There was no significant difference in patterns of prescribing or health status outcome for the two groups. Patients were more satisfied with nurse practitioner consultations (mean score 4.40 v 4.24 for general practitioners; adjusted difference 0.18, 0.092 to 0.257). This difference remained after consultation length was controlled for. There was no significant difference in health service costs (nurse practitioner 18.ll pound sterling v general practitioner 20.70 pound sterling adjusted difference 2.33 pound sterling - 1.62 pound sterling to 6.28 pound sterling). CONCLUSIONS The clinical care an health service costs of nurse practitioners and general practitioners were similar. If nurse practitioners were able to maintain the benefits while reducing their return consultation rate or shortening consultation times, they could be more cost effective than general practitioners.
Collapse
|
345
|
Schütz R, Cantin M, Roberts C, Greiner B, Uhlmann E, Leumann C. Olefinic Peptide Nucleic Acids (OPAs): New Aspects of the Molecular Recognition of DNA by PNA The team at the University of Bern thanks the Swiss National Science Foundation and Novartis Pharma AG, Basel, for generous financial support. Angew Chem Int Ed Engl 2000; 39:1250-1253. [PMID: 10767021 DOI: 10.1002/(sici)1521-3773(20000403)39:7<1250::aid-anie1250>3.0.co;2-e] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
346
|
Abstract
PURPOSE Although support groups are offered to many patients who have received a diagnosis of cancer, a majority of patients choose not to participate. This article reports the results of a study comparing the behavior of men diagnosed with prostate cancer and women diagnosed with breast cancer in their responses to invitations to participate in support groups. DESCRIPTION OF STUDY One hundred thirty women with breast cancer and 87 men with prostate cancer completed a structured telephone interview. The interview included questions about the patients' choices about support group participation. RESULTS Interview findings showed that men are less likely to join a support group, but those men who do join attend meetings for about 1 year, as do the women who join. Men and women cite essentially the same reasons for participation: to learn more about their diagnosis, to share their, concerns to compare their physical and emotional progress with other individuals. CLINICAL IMPLICATIONS These results indicate the need for further exploration of effective interventions for men and women who have been diagnosed with prostate and breast cancer, respectively, in an effort to offer support for the difficult psychological and emotional issues associated with their diagnoses. Although more women than men join support groups, the majority of both populations (67% for women, 87% for men) do not attend any support group meetings. Innovative approaches are needed to encourage participation in existing support groups or to design alternative interventions.
Collapse
|
347
|
Roberts C, Sarangi S, Southgate L, Wakeford R, Wass V. Oral examinations-equal opportunities, ethnicity, and fairness in the MRCGP. BMJ (CLINICAL RESEARCH ED.) 2000; 320:370-5. [PMID: 10657339 PMCID: PMC1127149 DOI: 10.1136/bmj.320.7231.370] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
348
|
Roberts C, Crofts N. Hitting up in the top end: characteristics of needle exchange clients in Darwin. Aust N Z J Public Health 2000; 24:82-5. [PMID: 10777985 DOI: 10.1111/j.1467-842x.2000.tb00729.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
OBJECTIVE Little is known about injecting drug use (IDU) and blood-borne viral (BBV) infection in rural Australia. METHOD These repeat cross-sectional studies were conducted during a two-week period in July and October-November 1998 at the Darwin needle exchange, with 129 and 121 respondents respectively. RESULTS The commonest drug of choice was heroin, but the commonest drug injected was morphine. Self-reported sharing of needles and syringes was uncommon. Self-reported serostatus for HIV was high (8% and 11.4% respectively), but seemingly mostly associated with sexual rather than IDU risk; for hepatitis C (HCV) status, these were 54% and 37%. Among IDUs of Aboriginal or Torres Strait Islander (ATSI) background, who made up 14% of the first round respondents, patterns of IDU and of BBV infection were the same as among non-ATSI respondents. CONCLUSIONS These surveys reveal patterns of IDU in Darwin that have both similarities and differences with those in the major urban centres in Australia. In the absence of a comprehensive methadone maintenance program, many participate in a more or less informal morphine substitution program. HIV is present among these IDUs, and the risks of further sexual transmission may be high. IMPLICATIONS These surveys confirm the presence among injecting drug users in Darwin of HIV, HBV and HCV, and of the risk for further spread of these viruses. Control of blood-borne virus transmission among IDUs requires an even greater commitment to abolishing sharing of needles and syringes, and therefore continued support and enhancement of needle and syringe availability.
Collapse
|
349
|
Roberts C. Universal precautions: improving the knowledge of trained nurses. BRITISH JOURNAL OF NURSING (MARK ALLEN PUBLISHING) 2000; 9:43-7. [PMID: 10887846 DOI: 10.12968/bjon.2000.9.1.6412] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Universal precautions relate to the management of blood-borne viruses such as human immunodeficiency virus (HIV) and hepatitis B and C. Advice on the transmission of blood-borne viruses and the precautionary measures used to reduce or eliminate cross-infection have been addressed by national and professional bodies. There is a significant amount of research which assesses trained nurses' knowledge of universal precautions and includes understanding of the transmission routes of blood-borne viruses and the measures required to prevent cross-infection. However, the majority of the literature indicates an incomplete knowledge among trained nurses of the principles and application of universal precautions. The ability of the trained nurse to fulfil his/her role as health educator, teacher and therefore effective infection control practitioner is questioned by the literature. This article discusses the role of education in improving the knowledge of trained nurses and considers the implementation of in-service training and preregistration education.
Collapse
|
350
|
Roberts PJ, Roberts C, Sibbald B, Torgerson DJ. The effect of a direct payment or a lottery on questionnaire response rates: a randomised controlled trial. J Epidemiol Community Health 2000; 54:71-2. [PMID: 10692967 PMCID: PMC1731530 DOI: 10.1136/jech.54.1.71] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|