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21.
References 相似文献
22.
Damien Stark Joel Barratt Tamalee Roberts Deborah Marriott John Harkness John Ellis 《The American journal of tropical medicine and hygiene》2010,82(4):614-619
Among 750 symptomatic and asymptomatic patients, Dientamoeba fragilis was detected at a prevalence of 5.2% and more common than Giardia intestinalis. Most infected patients presented with diarrhea and abdominal pain with symptoms greater than 2 weeks duration being common. Bacterial and viral causes of infection were excluded by routine microbiological techniques. Treatment of D. fragilis infection with either iodoquinol, paromomycin, or combination therapy resulted in the eradication of the parasite and complete resolution of symptoms. Treatment failure/relapses were associated only with the use of metronidazole. Nineteen patients were examined for pin worm, no Enterobius vermicularis, a proposed vector of transmission, were detected. Intermittent shedding of D. fragilis was found to be highly variable. These studies confirm the pathogenic nature of D. fragilis and we recommend laboratories routinely test for the organism. 相似文献
23.
Adam C. Soloff Xiangdong Liu Wentao Gao Richard D. Day Andrea Gambotto Simon M. Barratt‐Boyes 《European journal of immunology》2009,39(9):2437-2449
Heterologous adenovirus‐based vectors hold promise as preventative HIV vaccines but their capacity to induce effective T‐cell immunity in established infection has not been explored. We vaccinated rhesus macaques chronically infected with SIVmac251 and undergoing antiretroviral therapy (ART) with human adenovirus serotype 5‐based vectors expressing SIV Gag, Env, and Nef with and without IL‐15 and evaluated vaccine immunogenicity. Vaccination increased Ag‐specific T cells 20‐fold but did not expand the breadth of epitopes recognized or the quality of response, as the majority of CD8+ and CD4+ T cells produced only one cytokine irrespective of vaccination. Immunization transiently restored blood CD4+ central memory T cells (Tcm) and boosted CD4+ and CD8+ Tcm and effector cell responses but did not prevent virus rebound upon cessation of ART. Boosting with human adenovirus serotype 35‐based vectors during a second ART cycle increased Ag‐specific T cells to 50‐fold above pre‐vaccination levels and boosted CD4+ Tcm numbers but did not expand the breadth or quality of immunity or control virus levels following drug discontinuation. The number of blood CD4+ Tcm correlated positively with complexity of T‐cell responses and negatively with virus load, suggesting that more complete restoration of this subset through vaccination would be beneficial. 相似文献
24.
Macrophage accumulation in gut mucosa differentiates AIDS from chronic SIV infection in rhesus macaques 下载免费PDF全文
Zachary D. Swan Elizabeth R. Wonderlich Simon M. Barratt‐Boyes 《European journal of immunology》2016,46(2):446-454
The relationship between recruitment of mononuclear phagocytes to lymphoid and gut tissues and disease in HIV and SIV infection remains unclear. To address this question, we conducted cross‐sectional analyses of dendritic cell (DC) subsets and CD163+ macrophages in lymph nodes (LNs) and ileum of rhesus macaques with acute and chronic SIV infection and AIDS. In LNs significant differences were only evident when comparing uninfected and AIDS groups, with loss of myeloid DCs and CD103+ DCs from peripheral and mesenteric LNs, respectively, and accumulation of plasmacytoid DCs and macrophages in mesenteric LNs. In contrast, there were fourfold more macrophages in ileum lamina propria in macaques with AIDS compared with chronic infection, and this increased to 40‐fold in Peyer's patches. Gut macrophages exceeded plasmacytoid DCs and CD103+ DCs by ten‐ to 17‐fold in monkeys with AIDS but were at similar low frequencies as DCs in chronic infection. Gut macrophages in macaques with AIDS expressed IFN‐α and TNF‐α consistent with cell activation. CD163+ macrophages also accumulated in gut mucosa in acute infection but lacked expression of IFN‐α and TNF‐α. These data reveal a relationship between inflammatory macrophage accumulation in gut mucosa and disease and suggest a role for macrophages in AIDS pathogenesis. 相似文献
25.
C. W. Barratt H. Vyas B. R. Hayes-Gill J. A. Crowe 《Journal of medical engineering & technology》2013,37(1):17-24
Primary objective : This communication describes the initial stage of a research project concerning the monitoring of SpO2 in infants prone to periods of spontaneous oxygen desaturation whilst freely moving around their home environment. The primary aim was to determine an appropriate probe type and site together with an assessment of the suitability of two commercially available oximeter units. Research design : The study comprised 19 comparative tests, totalling 162 hours of recordings at resolution one sample every four seconds. Comparisons are drawn between probes, probe sites and pulse oximeters. Main outcomes/ results : The bias and precision is presented with respect to the probe and measurement site. Also, correlation between the trial and reference recordings is considered. Conclusions : It is concluded that ambulatory recording of SpO2 in infants utilizing equipment suitable for home monitoring can produce diagnostic data equivalent to that of the Ohmeda 3700 biox, but that an indication of movement artefact may be required for confirmation of accuracy. It became apparent that 'wrap around' probes, used on the index finger or big toe are the most suitable. 相似文献
26.
Daniel T Barratt Janet K Coller Andrew A Somogyi 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2006,(4):323-331
The TaqI A polymorphism (A(1)) of the dopamine D(2) receptor gene (DRD2), although not a specific predictor of opioid dependence, has been strongly associated with high levels of prior heroin use and poor treatment outcomes among methadone maintenance patients. The aims of this study were to confirm these findings via a retrospective analysis of A(1) allele frequency in methadone (n = 46) and buprenorphine (n = 25) patients, and non-opioid-dependent controls (n = 95). Subjects were genotyped at the DRD2 TaqI A locus using PCR amplification followed by TaqI restriction enzyme digestion and gel electrophoresis. For methadone and buprenorphine subjects, heroin use (prior to treatment), treatment outcomes, and withdrawal occurrence were determined from comprehensive case notes. No significant differences in A(1) allele frequency (%) were observed between: methadone (19.6%), buprenorphine (18.0%), and control (17.9%) groups (P > 0.7); successful and poor treatment outcome groups, methadone: 20.0% and 19.2%, respectively (P = 1.0); buprenorphine: 18.4% and 20.0%, respectively (P = 1.0). Also, there were no significant relationships between TaqI A genotype and prior heroin use (P = 0.47). However, among the successful methadone subjects, significantly fewer A(1) allele carriers experienced withdrawal than non-A(1) carriers (P = 0.04). In conclusion, the DRD2 genotype effects did not affect opioid maintenance treatment outcomes. This suggests the need for a further prospective investigation into the role of the DRD2 A(1) allele in heroin use and response to maintenance pharmacotherapies for opioid dependence. 相似文献
27.
Detection of erythrocyte membrane proteins, sialoglycoproteins, and lipids in the same polyacrylamide gel using a double-staining technique. 总被引:13,自引:1,他引:13 下载免费PDF全文
J K Dzandu M E Deh D L Barratt G E Wise 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(6):1733-1737
A silver/Coomassie brilliant blue R-250 staining technique that permits a color-coded differentiation of erythrocyte membrane proteins, sialoglycoproteins, and lipids in a single one-dimensional NaDodSO4/polyacrylamide gel has been described. Gels stained first with silver stain and then with Coomassie blue (CB) showed the characteristic blue staining of all conventional CB-sensitive membrane polypeptides, whereas periodic acid-Schiff reagent-sensitive sialoglycoproteins and lipids stained yellow. Several yellow Ag-stained bands corresponding to major and minor sialoglycoproteins were detected at Mr X 10(-3) of 88, 72, 65, 41, 35, 31, 28, 24, and 20. Neuraminidase treatment of intact erythrocytes caused shifts in the electrophoretic mobilities of several yellow-stained bands without affecting the CB-stained polypeptide pattern. These observations afforded evidence that the yellow-staining bands were sialoglycoproteins and lipids. The double-staining technique was used in a topological analysis of the membrane surface of the erythrocyte using protease digestion and selective solubilization. Trypsin cleaved the yellow bands at Mr 88,000 and 41,000. Membrane-associated cleavage products were noted at Mr 58,000 and 38,000. Pronase treatment of intact cells gave membrane-associated cleavage products at Mr 38,000 (yellow) and two CB-stained bands at Mr 58,000 and 60,000. These results suggested that the double-staining technique may be applicable in compositional and topological analyses of other biological membranes. 相似文献
28.
Arun Sahai Ased Ali Rachel Barratt Mohammed Belal Suzanne Biers Rizwan Hamid Christopher Harding Richard Parkinson Sheilagh Reid Nikesh Thiruchelvam Section of Female Neurological Urodynamic Urology British Association of Urological Surgeons 《BJU international》2021,128(5):539-547
Injuries to the bladder and ureter are uncommon but usually require prompt urological management. Due to their infrequent nature, Urologists maybe unfamiliar with managing these acute problems and may not work in specialist centres with readily available expertise in open and abdominal surgery. We aim to provide advice in the form of a consensus statement led by the Female, Neurological and Urodynamic Urology (FNUU) Section of the British Association of Urological Surgeons (BAUS), in consultation with BAUS members and consultants working in units throughout the UK, to create a comprehensive management pathway and a series of statements to aid clinicians. 相似文献
29.
The present investigation sought to determine whether the relationship between event-related potential (ERP) principal components analysis (PCA) factor scores and analogous waveform amplitude measures could be improved by high- and low-pass filtering the waveforms at a suitable cutoff value. Visual oddball ERPs were submitted to a varimax-rotated PCA performed on the variance/covariance matrix. Principal components corresponding to P300 and Slow Wave were obtained. In keeping with the fact that the variance/covariance PCA analyzes sources of variance around the grand mean waveform, the grand mean waveform was subtracted from each of the original waveforms, and baseline-referenced amplitude measurements were then made of P300 and Slow Wave. P300 was measured both as the maximum positive peak between 275 and 425 ms, and as the average amplitude during that interval. Slow Wave was measured as the average amplitude during the interval 400–700 ms. The P300 measurements were then repeated after high-pass filtering the difference waveforms at 2 Hz. Slow Wave measurements were repeated after low-pass filtering at 2 Hz. The value of 2 Hz was chosen as giving a reasonable cutoff based upon estimates of the wavelengths of the two components derived from inspection of their respective factor loading vectors. The correlation between factor scores and amplitude measurements was .94 for unfiltered Slow Wave and actually declined slightly but significantly to .91 when the waveforms were low-pass filtered. It would appear that Slow Wave factor scores emerging from a PCA can be fairly well approximated by a time-band measurement algorithm, and that this approximation is not improved by low-pass filtering. For both filtered and unfiltered measurements of P300, the amplitude/factor score correlation was significantly higher for the time-band method than for the peak method. Further, high-pass filtering at 2 Hz improved the time-band/factor score correlation significantly from .62 to .75. This improvement is probably because the unfiltered measurements were tapping sources of variance due both to the higher frequency P300 component as well as a simultaneously active, lower frequency Slow Wave component. Theoretical implications of these findings are discussed. 相似文献
30.
Mehdi Kordi Jonathan Folland Stuart Goodall Nicos Haralabidis Tom Maden-Wilkinson Tejal Sarika Patel Jonathan Leeder Paul Barratt Glyn Howatson 《Scandinavian journal of medicine & science in sports》2020,30(2):227-237
Mechanical peak power output (PPO) is a determinant of performance in sprint cycling. The purpose of this study was to examine the relationship between PPO and putative physiological determinants of PPO in elite cyclists, and to compare sprint performance between elite sprint and endurance cyclists. Thirty-five elite cyclists (18 endurance; 17 sprint) performed duplicate sprint cycling laboratory tests to establish PPO and its mechanical components. Quadriceps femoris (QVOL) and hamstring muscle volume (HAMVOL) were assessed with MRI, vastus lateralis pennation angle (PθVL) and fascicle length (FLVL) were determined with ultrasound imaging, and neuromuscular activation of three muscles was assessed using EMG at PPO during sprint cycling. For the whole cohort, there was a wide variability in PPO (range 775-2025 W) with very large, positive, bivariate relationships between PPO and QVOL (r = .87), HAMVOL (r = .71), and PθVL (r = .81). Step-wise multiple regression analysis revealed that 87% of the variability in PPO between cyclists was explained by two variables QVOL (76%) and PθVL (11%). The sprint cyclists had greater PPO (+61%; P < .001 vs endurance), larger QVOL (P < .001), and BFVOL (P < .001) as well as more pennate vastus lateralis muscles (P < .001). These findings emphasize the importance of quadriceps muscle morphology for sprint cycling events. 相似文献