IntroductionVaccine-specific immune responses vary between populations and are often impaired in low income, rural settings. Drivers of these differences are not fully elucidated, hampering ...identification of strategies for optimising vaccine effectiveness. We hypothesise that urban–rural (and regional and international) differences in vaccine responses are mediated to an important extent by differential exposure to chronic infections, particularly parasitic infections.Methods and analysisThree related trials sharing core elements of study design and procedures (allowing comparison of outcomes across the trials) will test the effects of (1) individually randomised intervention against schistosomiasis (trial A) and malaria (trial B), and (2) Bacillus Calmette-Guérin (BCG) revaccination (trial C), on a common set of vaccine responses. We will enrol adolescents from Ugandan schools in rural high-schistosomiasis (trial A) and rural high-malaria (trial B) settings and from an established urban birth cohort (trial C). All participants will receive BCG on day ‘0’; yellow fever, oral typhoid and human papilloma virus (HPV) vaccines at week 4; and HPV and tetanus/diphtheria booster vaccine at week 28. Primary outcomes are BCG-specific IFN-γ responses (8 weeks after BCG) and for other vaccines, antibody responses to key vaccine antigens at 4 weeks after immunisation. Secondary analyses will determine effects of interventions on correlates of protective immunity, vaccine response waning, priming versus boosting immunisations, and parasite infection status and intensity. Overarching analyses will compare outcomes between the three trial settings. Sample archives will offer opportunities for exploratory evaluation of the role of immunological and ‘trans-kingdom’ mediators in parasite modulation of vaccine-specific responses.Ethics and disseminationEthics approval has been obtained from relevant Ugandan and UK ethics committees. Results will be shared with Uganda Ministry of Health, relevant district councils, community leaders and study participants. Further dissemination will be done through conference proceedings and publications.Trial registration numbersISRCTN60517191, ISRCTN62041885, ISRCTN10482904.
The duration of influenza virus shedding in HIV-infected adults is unknown and could affect quarantine and treatment recommendations. Participants were monitored for influenza-like illness (ILI), ...defined as fever and cough or sore throat, using weekly telephone audio computer-assisted self-interviews. Those with ILI were further evaluated at three HIV specialty clinics. For those with influenza, we collected nasopharyngeal washes every 3 days after the date of confirmed influenza infection for 21-28 days; specimens underwent reverse transcriptase - polymerase chain reaction (RT-PCR) and viral culture. Duration of influenza virus shedding was the interval from the date of onset (day 0) of ILI to the date of last culture-positive specimen. Characteristics were compared between patients with and without influenza using Fisher's exact test. We used the Wilcoxon rank-sum test to examine factors that may have affected influenza virus shedding. From October 2010 to April 2011, we enrolled 961 participants in syndromic surveillance and diagnosed 20 patients with influenza whose characteristics were as follows: median age 48 years (interquartile range IQR: 43-53), 60% male, 50% non-Hispanic black, 95% had been prescribed combination highly active antiretroviral therapy (cART), 85% were virologically suppressed (HIV RNA <400 copies/ml), median CD4 cell count 317 cells/mm
(IQR: 190-544), and median follow-up time 21 days (IQR: 19-22). Compared with persons without influenza, persons with influenza were more likely to be older, use injection drugs, and have a lower median CD4 cell count and were less likely to have had an influenza vaccination in the past 12 months. Median durations of shedding, PCR detection, and ILI symptoms were 3 (IQR: 0-5), 10 (IQR: 6-15), and 14 days (IQR: 12-26), respectively. Median days of shedding were similar among patients with and without any prior influenza vaccination (0 vs. 4, p = .448), HIV viral suppression (2 vs. 6, p = .053), and oseltamivir use (5 vs. 0, p = .083). HIV-infected persons on cART in our study shed influenza virus for a similar duration as that reported for HIV-uninfected persons.
Our aim was to use early magnetic resonance imaging (MRI) to investigate the causes of cognitive decline in elderly people with mild cognitive impairment (MCI). Baseline structural and flow ...quantification MR sequences, and clinical and neuropsychological follow-up for at least two years, were performed on 62 elderly subjects with MCI. Of these subjects, 17 progressed to dementia, and 15 of these progressed to dementia of the Alzheimer type (DAT). Conversion to clinically diagnosed DAT was related to six distinct MR profiles, including one profile suggesting severe AD (20% of these converters) and five profiles suggesting severe cerebrovascular dysfunction. Two profiles suggested arteriosclerotic brain degeneration, one profile suggested severe venous windkessel dysfunction, and two suggested marked cerebral hypoperfusion associated with very low craniospinal compliance or marked brain atrophy. As compared with vascular MR type converters, AD MR type converters showed high executive and mobility predementia performances. Severe whole anteromesial temporal atrophy and predominantly left brain atrophy on visual MR analysis was only observed in AD MR type converters. In conclusion, these observations enhance the pathogenic complexity of the Alzheimer syndrome, and suggest that the role of arteriosclerotic brain degeneration in late life dementia is underestimated.
To present a novel magnetic resonance (MR) method of analysis of cerebrospinal fluid (CSF) flow dynamics.
Fifty-one subjects were explored with phase-contrast cine MR imaging. There were 36 ...volunteers, 9 patients with normal pressure hydrocephalus (NPH), and 6 patients with asymptomatic ventricular dilation (VD). The transfer function XFRA/CSF from the arterial pulse waves (APWs) and the CSF pulse waves (CSFPWs) and the transfer function XFRCSF/SS from the CSF pulse waves (CSFPWs) and the sagittal sinus pulse waves (SSPWs) were studied separately.
There was a significant difference in the amplitude spectrum of the XFRA/CSF of patients with VD and volunteers (P < 0.05) and in that of patients with NPH and volunteers (P = 0.005). The amplitude of the fundamental frequency was higher in the NPH group than in the VD group (P = 0.02). In patients with NPH, the amplitude spectrum of XFRCSF/SS showed an attenuation of the pulse wave components that significantly differed from the observed amplification in healthy subjects (P = 0.009) and patients with VD (P = 0.012).
This systems analysis method could help to detect increased venous compliance in VD and decreased venous compliance in NPH.
Objectives
The aim of the Pre-Al study is to evaluate and compare the predictive value of different tools for an early identification of Alzheimer’s disease.
Design & participants
Patients coming for ...consultation to memory clinics without dementia were included if they had an objective memory or attention trouble assessed by a MMSE score > 25 (with at least one missing item at the words recall) and / or an Isaac set test score < 28. All were examined by a neuropsychological battery (Free and Cued Selective Reminding Test, digit ordering test, WAIS-R digit symbol, Trail making test, Benton visual retention test, verbal fluency, confrontation naming and Baddeley’s double task test). A subpopulation received an MRI and SPECT assessment.
Results & discussion
251 patients were included (mean age: 72.0 years; mean education duration: 10.9 years). Validation of the predictive tests will be based on the comparison of these tests in patients developing dementia and others, after a follow-up of at least 3 years. This paper presents methodology of the study and the population description.
Our aim was to use early magnetic resonance imaging (MRI) to investigate the causes of cognitive decline in elderly people with mild cognitive impairment (MCI). Baseline structural and flow ...quantification MR sequences, and clinical and neuropsychological follow-up for at least two years, were performed on 62 elderly subjects with MCI. Of these subjects, 17 progressed to dementia, and 15 of these progressed to dementia of the Alzheimer type (DAT). Conversion to clinically diagnosed DAT was related to six distinct MR profiles, including one profile suggesting severe AD (20% of these converters) and five profiles suggesting severe cerebrovascular dysfunction. Two profiles suggested arteriosclerotic brain degeneration, one profile suggested severe venous windkessel dysfunction, and two suggested marked cerebral hypoperfusion associated with very low craniospinal compliance or marked brain atrophy. As compared with vascular MR type converters, AD MR type converters showed high executive and mobility predementia performances. Severe whole anteromesial temporal atrophy and predominantly left brain atrophy on visual MR analysis was only observed in AD MR type converters. In conclusion, these observations enhance the pathogenic complexity of the Alzheimer syndrome, and suggest that the role of arteriosclerotic brain degeneration in late life dementia is underestimated.
Patterns of leukoaraiosis were analyzed on both T2-weighted fast fluid-attenuated inversion-recovery and 3D T1-weighted sequences in 23 community-dwelling older subjects with mild cognitive ...impairment. Mobility assessment had allowed their classification into higher and lower mobility groups (
P<0.0001). Lower mobility appeared correlated with frontal subependymal lesions (
P=0.0005). The absence of marked ventriculomegaly, any thick caps, deep white matter lesions curved along the ventricles bodies, large deep white matter lesions, deep grey matter leukoaraiosis was an hallmark of the higher mobility group (
P<0.0001). High resolution MRI demonstrated regular patterns of the subependymal lesions and detected perivascular distribution in other forms of leukoaraiosis. It suggests that the underlying mechanism of mobility decline in the elderly may be impairment of cerebrospinal fluid dynamics with cerebral small vessel disease.
Our aim was to use early magnetic resonance imaging (MRI) to investigate the causes of cognitive decline in elderly people with mild cognitive impairment (MCI). Baseline structural and flow ...quantification MR sequences, and clinical and neuropsychological follow-up for at least two years, were performed on 62 elderly subjects with MCI. Of these subjects, 17 progressed to dementia, and 15 of these progressed to dementia of the Alzheimer type (DAT). Conversion to clinically diagnosed DAT was related to six distinct MR profiles, including one profile suggesting severe AD (20% of these converters) and five profiles suggesting severe cerebrovascular dysfunction. Two profiles suggested arteriosclerotic brain degeneration, one profile suggested severe venous windkessel dysfunction, and two suggested marked cerebral hypoperfusion associated with very low craniospinal compliance or marked brain atrophy. As compared with vascular MR type converters, AD MR type converters showed high executive and mobility predementia performances. Severe whole anteromesial temporal atrophy and predominantly left brain atrophy on visual MR analysis was only observed in AD MR type converters. In conclusion, these observations enhance the pathogenic complexity of the Alzheimer syndrome, and suggest that the role of arteriosclerotic brain degeneration in late life dementia is underestimated.