A double-blinded randomised controlled trial of vitamin A drops to treat post-viral olfactory loss: study protocol for a proof-of-concept study for vitamin A nasal drops in post-viral olfactory loss (APOLLO)

BACKGROUND

Smell loss is a common problem with an estimated 5% of the population having no functioning sense of smell. Viral causes of smell loss are the second most common cause and the coronavirus (COVID-19) pandemic is estimated to have caused 20,000 more people this year to have a lasting loss of smell. Isolation, depression, anxiety, and risk of danger from hazards such as toxic gas and spoiled food are all negative impacts. It also affects appetite with weight loss/gain in two-thirds of those affected. Phantosmia or smell distortion can also occur making most foods seem unpalatable. Smell training has been tried with good results in the immediate post-viral phase. Evidence behind treatment with steroids has not shown to have proven effectiveness. With this, a key problem for patients and their clinicians is the lack of proven effective therapeutic treatment options. Based on previous studies, there is some evidence supporting the regenerative potential of retinoic acid, the metabolically active form of vitamin A in the regeneration of olfactory receptor neurons. It is based on this concept that we have chosen vitamin A as our study comparator.

AIM

To undertake a two-arm randomised trial of intranasally delivered vitamin A vs no intervention to determine proof of concept.

METHODS/DESIGN

The study will compare 10,000 IU once daily Vitamin A self-administered intranasal drops versus peanut oil drops (placebo) delivered over 12 weeks in patients with post-viral olfactory loss. Potentially eligible patients will be recruited from the Smell & Taste Clinic and via the charity Fifth Sense. They will be invited to attend the Brain Imaging Centre at the University of East Anglia on two occasions, 3 months apart. If they meet the eligibility criteria, they will be consented to enter the study and randomised to receive vitamin A drops or no treatment in a 2:1 ratio. MRI scanning will enable volumetric measurement of the OB and ROS; fMRI will then be conducted using an olfactometer to deliver pulsed odours-phenethylalcohol (rose-like) and hydrogen sulphide (rotten eggs). Participants will also perform a standard smell test at both visits as well as complete a quality-of-life questionnaire. Change in OB volume will be the primary outcome measure.

DISCUSSION

We expect the outputs of this study to enable a subsequent randomised controlled trial of Vitamin A versus placebo. With PPI input we will make the outputs publicly available using journals, conferences, and social media via Fifth Sense. We have already prepared a draft RCT proposal in partnership with the Norwich Clinical Trials Unit and plan to develop this further in light of the findings.

TRIAL REGISTRATION

ISRCTN registry 39523. Date of registration in the primary registry: 23rd February 2021.

Association between panic disorder and childhood adversities: a systematic review and meta-analysis

BACKGROUND

Adverse childhood experiences (ACEs) increase the risk of mental health difficulties in general, but the link to panic disorder (PD) has received comparatively little attention. There are no data for the magnitudes between ACEs and PD. This systematic review and meta-analysis estimated the overall, as well as the subgroups, odds ratio of having PD in adults who report ACEs, compared to adults who do not.

METHODS

The study was pre-registered on PROSPERO [CRD42018111506] and the database was searched in June 2021. In order to overcome the violation of independent assumptions due to multiple estimations from the same samples, we utilized a robust variance estimation model that supports meta-analysis for clustered estimations. Accordingly, an advanced method relaxing the distributional and asymptotic assumptions was used to assess publication bias and sensitivity.

RESULTS

The literature search and screening returned 34 final studies, comprising 192,182 participants. Ninety-six estimations of 20 types of ACEs were extracted. Pooled ORs are: overall 2.2, CI (1.82-2.58), sexual abuse 1.92, CI (1.37-2.46), physical abuse 1.71, CI (1.37-2.05), emotional abuse 1.61, CI (0.868-2.35), emotional neglect 1.53, CI (0.756-2.31), parental alcoholism 1.83, CI (1.24-2.43), and parental separation/loss 1.82, CI (1.14-2.50). No between-group difference was identified by either sociolegal classification (abuse, neglect, household dysfunction) or threat-deprivation dimensions (high on threat, high on deprivation and mixed).

CONCLUSIONS

There are links of mild to medium strength between overall ACEs and PD as well as individual ACEs. The homogeneous effect sizes across ACEs either suggest the effects of ACEs on PD are comparable, or raised the question whether the categorical or dimensional approaches to classifying ACEs are the definitive ways to conceptualize the impact of ACEs on later mental health.

Acute stress and PTSD among trauma-exposed children and adolescents: Computational prediction and interpretation

BACKGROUND

Youth receiving medical care for injury are at risk of PTSD. Therefore, accurate prediction of chronic PTSD at an early stage is needed. Machine learning (ML) offers a promising approach to precise prediction and interpretation.

AIMS

The study proposes a clinically useful predictive model for PTSD 6-12 months after injury, analyzing the relationship among predictors, and between predictors and outcomes.

METHODS

A ML approach was utilized to train models based on 1167 children and adolescents of nine perspective studies. Demographics, trauma characteristics and acute traumatic stress (ASD) symptoms were used as initial predictors. PTSD diagnosis at six months was derived using DSM-IV PTSD diagnostic criteria. Models were validated on external datasets. Shapley value and partial dependency plot (PDP) were applied to interpret the final model.

RESULTS

A random forest model with 13 predictors (age, ethnicity, trauma type, intrusive memories, nightmares, reliving, distress, dissociation, cognitive avoidance, sleep, irritability, hypervigilance and startle) yielded F-scores of.973,0.902 and.961 with training and two external datasets. Shapley values were calculated for individual and grouped predictors. A cumulative effect for intrusion symptoms was observed. PDP showed a non-linear relationship between age and PTSD, and between ASD symptom severity and PTSD. A 43 % difference in the risk between non-minority and minority ethnic groups was detected.

CONCLUSIONS

A ML model demonstrated excellent classification performance and good potential for clinical utility, using a few easily obtainable variables. Model interpretation gave a comprehensive quantitative analysis on the operations among predictors, in particular ASD symptoms.

A novel Artificial Intelligence-based tool to assess anticholinergic burden: a survey

BACKGROUND

many medications possess anticholinergic activity. Their use is associated with a number of serious adverse effects including cognitive effects. The cumulative anticholinergic effect of medications as assessed by tools such as the anticholinergic burden scale (AchB) can identify people particularly at risk of anticholinergic side-effects. Currently, >20 tools are available for clinicians to use, but there is no consensus on the most appropriate tool.

METHODS

a newly created online tool-International Anticholinergic Cognitive Burden Tool (IACT)-based on natural language processing and chemical structure analysis, was developed and made available for clinicians to test its functions. We carried out a survey (between 8th of February and 31st of March 2021) to assess the overall need for an assessment tool as well as the usability of the IACT.

RESULTS

a total of 110 responses were received from different countries and practitioners' groups. The majority of the participants (86.11%) stated they would use a tool for AchB assessment if available and when they were asked to rate the IACT against other tools, amongst 34 responders, 20.59% rated it better and 8.82% rated it significantly better, 44.12% rated it neither better, nor worse, 14.71% rated it worse and 11.76% somewhat worse.

CONCLUSION

there is a need for an anticholinergic burden calculator to assess the anticholinergicity of medications. Tools such as the IACT potentially could meet this demand due to its ability to assign scores to current and new medications appearing on the market based both on their chemical structure and reported adverse pharmacological effects.

Chronic Consumption of Cranberries (Vaccinium macrocarpon) for 12 Weeks Improves Episodic Memory and Regional Brain Perfusion in Healthy Older Adults: A Randomised, Placebo-Controlled, Parallel-Groups Feasibility Study

Background

Ageing is highly associated with cognitive decline and modifiable risk factors such as diet are believed to protect against this process. Specific dietary components and in particular, (poly)phenol-rich fruits such as berries have been increasingly recognised for their protection against age-related neurodegeneration. However, the impact of cranberries on cognitive function and neural functioning in older adults remains unclear.

Design

A 12-week parallel randomised placebo-controlled trial of freeze-dried cranberry powder was conducted in 60 older adults aged between 50 and 80 years. Cognitive assessment, including memory and executive function, neuroimaging and blood sample collection were conducted before and after the intervention to assess the impact of daily cranberry consumption on cognition, brain function and biomarkers of neuronal signalling.

Results

Cranberry supplementation for 12 weeks was associated with improvements in visual episodic memory in aged participants when compared to placebo. Mechanisms of action may include increased regional perfusion in the right entorhinal cortex, the accumbens area and the caudate in the cranberry group. Significant decrease in low-density lipoprotein (LDL) cholesterol during the course of the intervention was also observed. No significant differences were, however, detected for BDNF levels between groups.

Conclusions

The results of this study indicate that daily cranberry supplementation (equivalent to 1 small cup of cranberries) over a 12-week period improves episodic memory performance and neural functioning, providing a basis for future investigations to determine efficacy in the context of neurological disease. This trial was registered at clinicaltrials.gov as NCT03679533 and at ISRCTN as ISRCTN76069316.

POS0018 INVESTIGATING VIRTUAL IMMERSIVE EXPERIENCES IN THE MANAGEMENT OF CHRONIC PAIN – THE VIPA STUDY (PRELIMINARY RESULTS)

Background:

Chronic pain is debilitating and prevalent. Current non-pharmacological management of pain conditions such as Fibromyalgia Syndrome (FMS) are labour intensive to implement and poorly available, especially during the pandemic. There is an urgent need to develop widely adoptable, innovative treatment options for pain cohorts.

Virtual reality (VR) provides an innovative therapeutic tool, immersing users within a three-dimensional, interactive virtual environment with use of a head-mounted display (HMD). Beneficial effects of VR have been demonstrated in acute pain1, with limited studies in chronic pain. Given the variation of available VR technologies, it is vital to investigate the impact of different VR characteristics on acceptability in specific chronic pain cohorts.

Objectives:

This feasibility study aims to establish the acceptability of four different VR technologies in patients with FMS whilst undertaking a single interactive VR experience.

Methods:

Patients with FMS were recruited through outpatient clinics at the Norfolk and Norwich University Hospital. Baseline questionnaires were used including the McGill pain questionnaire (MPQ-SF), pain visual analogue scale (VAS) and Revised Fibromyalgia Impact Questionnaire (FIQR). Subjective experience questionnaires collected acceptability data with 7-point Likert scale rating questions (strongly disagree to strongly agree). The simulation sickness questionnaire (SSQ) gained side-effect data (total severity score: 0-235). Categorical data were described using frequencies; and continuous data using mean and standard deviation. Likert-scale data were dichotomised (rating ≤3: disagree, rating ≥5: agree).

Four VR systems representing the spectrum of commercially available technologies were used (seen in Figure 1). These possess different characteristics including screen resolution, processor speed, weight, strap and controller type. The VR experience used with each headset was co-developed alongside industry partners (Orbital Global). Participants are immersed within a naturalistic environment, situated on a wooden boat travelling slowly along a calm river surrounded by trees and hills. The interactive element involves the user shooting targets that appear using handheld controllers.

Results:

13 patients with FMS were included (mean age 41.8±15.6, 92.3% female). Most had severe disease (mean FIQR 67.8±14.1) with moderate self-reported pain at baseline (mean MPQ 25.5±8.8, VAS 6.0±1.7). Most had no previous VR exposure (69.2%). 100% of participants agreed that they would be open to using VR for future pain management (mean rating 6.5±0.7) and that they would use VR regularly at home (mean rating 6.5±0.7). VR HMD comfort and enjoyment data are presented in Table 1. Mean ratings of comfort were high across the four HMDs (Gear VR: 4.9±1.7, Oculus Go: 4.5±1.8, Oculus Quest 5.3±1.9, Oculus Rift 6.6±0.5). Mean ratings of enjoyment with each HMD were also high (Gear VR: 5.4±1.6, Oculus Go: 5.4±1.8, Oculus Quest: 5.6±1.9, Oculus Rift S: 6.6±0.5). Low levels of side effects were described with mean SSQ total scores ranging from 20.1±16.8 (Oculus Rift S) to 38.0±23.9 (Gear VR).

Conclusion:

Preliminary results indicate that FMS patients find VR acceptable, describing high ratings of comfort and enjoyment across the VR HMD spectrum. Side-effect frequency was low, with most settling after HMD removal. All participants were open to future use of VR for home-based pain management.

References:

[1]Dascal J, Reid M, Ishak WW, Spiegel B, Recacho J, Rosen B, Danovitch I. Virtual reality and medical inpatients: A systematic review of randomized, controlled trials. Innov Clin Neurosci 2017;14(1-2):14-21

Table 1.

Subjective experience results across VR HMDs

Mean Likert scale ratings (% agreement: rating ≥5)VR HMDOverall, I found the VR experience using this equipment comfortableOverall, I enjoyed using this VR headsetGear VR4.9±1.7 (62%)5.4±1.6 (77%)Oculus Go4.5±1.8 (54%)5.4±1.8 (75%)Oculus Quest5.3±1.9 (77%)5.6±1.9 (100%)Oculus Rift S6.6±0.5 (100%)6.6±0.5 (100%)

Acknowledgements:

I would like to acknowledge the contributions of the staff working within the Rheumatology department at the Norfolk and Norwich University Hospital. I would also like to thank and acknowledge our participants for being involved in the study.

Disclosure of Interests:

Jordan Tsigarides Grant/research support from: Our digital health industry partners (Orbital Global) provided a small financial contribution to support this study., Vanessa Grove: None declared, Dheeraj Sethi: None declared, Jacqueline Chipping: None declared, Susan Miles: None declared, Nicholas Shenker: None declared, Saber Sami: None declared, Alex MacGregor: None declared.

Differential vulnerability of the cerebellum in healthy ageing and Alzheimer's disease

Recent findings challenge the prior notion that the cerebellum remains unaffected by Alzheimer's disease (AD). Yet, it is unclear whether AD exacerbates age-related cerebellar grey matter decline or engages distinct structural and functional territories. We performed a meta-analysis of cerebellar grey matter loss in normal ageing and AD. We mapped voxels with structural decline onto established brain networks, functional parcellations, and along gradients that govern the functional organisation of the cerebellum. Importantly, these gradients track continuous changes in cerebellar specialisation providing a more nuanced measure of the functional profile of regions vulnerable to ageing and AD. Gradient 1 progresses from motor to cognitive territories; Gradient 2 isolates attentional processing; Gradient 3 captures lateralisation differences in cognitive functions. We identified bilateral and right-lateralised posterior cerebellar atrophy in ageing and AD, respectively. Age- and AD-related structural decline only showed partial spatial overlap in right lobule VI/Crus I. Despite the seemingly distinct patterns of AD- and age-related atrophy, the functional profiles of these regions were similar. Both participate in the same macroscale networks (default mode, frontoparietal, attention), support executive functions and language processing, and did not exhibit a difference in relative positions along Gradients 1 or 2. However, Gradient 3 values were significantly different in ageing vs. AD, suggesting that the roles of left and right atrophied cerebellar regions exhibit subtle functional differences despite their membership in similar macroscale networks. These findings provide an unprecedented characterisation of structural and functional differences and similarities in cerebellar grey matter loss between normal ageing and AD.

Global Determinants of Navigation Ability

Human spatial ability is modulated by a number of factors, including age [1-3] and gender [4, 5]. Although a few studies showed that culture influences cognitive strategies [6-13], the interaction between these factors has never been globally assessed as this requires testing millions of people of all ages across many different countries in the world. Since countries vary in their geographical and cultural properties, we predicted that these variations give rise to an organized spatial distribution of cognition at a planetary-wide scale. To test this hypothesis, we developed a mobile-app-based cognitive task, measuring non-verbal spatial navigation ability in more than 2.5 million people and sampling populations in every nation state. We focused on spatial navigation due to its universal requirement across cultures. Using a clustering approach, we find that navigation ability is clustered into five distinct, yet geographically related, groups of countries. Specifically, the economic wealth of a nation was predictive of the average navigation ability of its inhabitants, and gender inequality was predictive of the size of performance difference between males and females. Thus, cognitive abilities, at least for spatial navigation, are clustered according to economic wealth and gender inequalities globally, which has significant implications for cross-cultural studies and multi-center clinical trials using cognitive testing.

Neurophysiological signatures of Alzheimer's disease and frontotemporal lobar degeneration: pathology versus phenotype

The disruption of brain networks is characteristic of neurodegenerative dementias. However, it is controversial whether changes in connectivity reflect only the functional anatomy of disease, with selective vulnerability of brain networks, or the specific neurophysiological consequences of different neuropathologies within brain networks. We proposed that the oscillatory dynamics of cortical circuits reflect the tuning of local neural interactions, such that different pathologies are selective in their impact on the frequency spectrum of oscillations, whereas clinical syndromes reflect the anatomical distribution of pathology and physiological change. To test this hypothesis, we used magnetoencephalography from five patient groups, representing dissociated pathological subtypes and distributions across frontal, parietal and temporal lobes: amnestic Alzheimer's disease, posterior cortical atrophy, and three syndromes associated with frontotemporal lobar degeneration. We measured effective connectivity with graph theory-based measures of local efficiency, using partial directed coherence between sensors. As expected, each disease caused large-scale changes of neurophysiological brain networks, with reductions in local efficiency compared to controls. Critically however, the frequency range of altered connectivity was consistent across clinical syndromes that shared a likely underlying pathology, whilst the localization of changes differed between clinical syndromes. Multivariate pattern analysis of the frequency-specific topographies of local efficiency separated the disorders from each other and from controls (accuracy 62% to 100%, according to the groups' differences in likely pathology and clinical syndrome). The data indicate that magnetoencephalography has the potential to reveal specific changes in neurophysiology resulting from neurodegenerative disease. Our findings confirm that while clinical syndromes have characteristic anatomical patterns of abnormal connectivity that may be identified with other methods like structural brain imaging, the different mechanisms of neurodegeneration also cause characteristic spectral signatures of physiological coupling that are not accessible with structural imaging nor confounded by the neurovascular signalling of functional MRI. We suggest that these spectral characteristics of altered connectivity are the result of differential disruption of neuronal microstructure and synaptic physiology by Alzheimer's disease versus frontotemporal lobar degeneration.

Cerebellar atrophy in neurodegeneration-a meta-analysis

INTRODUCTION

The cerebellum has strong cortical and subcortical connectivity, but is rarely taken into account for clinical diagnosis in many neurodegenerative conditions, particularly in the absence of clinical ataxia. The current meta-analysis aims to assess patterns of cerebellar grey matter atrophy in seven neurodegenerative conditions (Alzheimer's disease (AD), Parkinson's disease (PD) and Huntington's disease (HD), frontotemporal dementia (FTD), amyotrophic lateral sclerosis (ALS), multiple system atrophy (MSA), progressive supranuclear palsy (MSP)).

METHODS

We carried out a systematic search in PubMed (any date: 14 July 2016) and a hand search of references from pertinent articles according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The authors were contacted to provide missing coordinate data. Peer-reviewed studies with direct comparison of patient and control groups, and availability of coordinate data of grey matter cerebellar atrophy in patients were included. These coordinates were used in an anatomical likelihood estimation meta-analysis.

RESULTS

Across 54 studies, clusters of cerebellar atrophy were found for AD, ALS, FTD, MSA, and PSP. Atrophy patterns were largely disease-specific, with overlap in certain areas of the cerebellar hemisphere, which showed marked atrophy in AD, ALS, FTD and PSP (Crus I/II), and MSA and PSP (lobules I-IV), respectively. Atrophy colocated with cerebellar areas implicated for motor (PSP, MSA) or cognitive symptoms (FTD, ALS, PSP) in the diseases.

DISCUSSION

Our findings suggest that cerebellar changes are largely disease-specific and correspond to cortical or subcortical changes in neurodegenerative conditions. High clinical variability in PD and HD samples may explain the absence of findings for consistent grey matter loss across studies. Our results have clinical implications for diagnosis and cerebellar neuroimaging referencing approaches.

18F-AV-1451 positron emission tomography in Alzheimer's disease and progressive supranuclear palsy

The ability to assess the distribution and extent of tau pathology in Alzheimer's disease and progressive supranuclear palsy in vivo would help to develop biomarkers for these tauopathies and clinical trials of disease-modifying therapies. New radioligands for positron emission tomography have generated considerable interest, and controversy, in their potential as tau biomarkers. We assessed the radiotracer 18F-AV-1451 with positron emission tomography imaging to compare the distribution and intensity of tau pathology in 15 patients with Alzheimer's pathology (including amyloid-positive mild cognitive impairment), 19 patients with progressive supranuclear palsy, and 13 age- and sex-matched controls. Regional analysis of variance and a support vector machine were used to compare and discriminate the clinical groups, respectively. We also examined the 18F-AV-1451 autoradiographic binding in post-mortem tissue from patients with Alzheimer's disease, progressive supranuclear palsy, and a control case to assess the 18F-AV-1451 binding specificity to Alzheimer's and non-Alzheimer's tau pathology. There was increased 18F-AV-1451 binding in multiple regions in living patients with Alzheimer's disease and progressive supranuclear palsy relative to controls [main effect of group, F(2,41) = 17.5, P < 0.0001; region of interest × group interaction, F(2,68) = 7.5, P < 0.00001]. More specifically, 18F-AV-1451 binding was significantly increased in patients with Alzheimer's disease, relative to patients with progressive supranuclear palsy and with control subjects, in the hippocampus and in occipital, parietal, temporal, and frontal cortices (t's > 2.2, P's < 0.04). Conversely, in patients with progressive supranuclear palsy, relative to patients with Alzheimer's disease, 18F-AV-1451 binding was elevated in the midbrain (t = 2.1, P < 0.04); while patients with progressive supranuclear palsy showed, relative to controls, increased 18F-AV-1451 uptake in the putamen, pallidum, thalamus, midbrain, and in the dentate nucleus of the cerebellum (t's > 2.7, P's < 0.02). The support vector machine assigned patients' diagnoses with 94% accuracy. The post-mortem autoradiographic data showed that 18F-AV-1451 strongly bound to Alzheimer-related tau pathology, but less specifically in progressive supranuclear palsy. 18F-AV-1451 binding to the basal ganglia was strong in all groups in vivo. Postmortem histochemical staining showed absence of neuromelanin-containing cells in the basal ganglia, indicating that off-target binding to neuromelanin is an insufficient explanation of 18F-AV-1451 positron emission tomography data in vivo, at least in the basal ganglia. Overall, we confirm the potential of 18F-AV-1451 as a heuristic biomarker, but caution is indicated in the neuropathological interpretation of its binding. Off-target binding may contribute to disease profiles of 18F-AV-1451 positron emission tomography, especially in primary tauopathies such as progressive supranuclear palsy. We suggest that 18F-AV-1451 positron emission tomography is a useful biomarker to assess tau pathology in Alzheimer's disease and to distinguish it from other tauopathies with distinct clinical and pathological characteristics such as progressive supranuclear palsy.

Atomoxetine Enhances Connectivity of Prefrontal Networks in Parkinson's Disease

Cognitive impairment is common in Parkinson's disease (PD), but often not improved by dopaminergic treatment. New treatment strategies targeting other neurotransmitter deficits are therefore of growing interest. Imaging the brain at rest ('task-free') provides the opportunity to examine the impact of a candidate drug on many of the brain networks that underpin cognition, while minimizing task-related performance confounds. We test this approach using atomoxetine, a selective noradrenaline reuptake inhibitor that modulates the prefrontal cortical activity and can facilitate some executive functions and response inhibition. Thirty-three patients with idiopathic PD underwent task-free fMRI. Patients were scanned twice in a double-blind, placebo-controlled crossover design, following either placebo or 40-mg oral atomoxetine. Seventy-six controls were scanned once without medication to provide normative data. Seed-based correlation analyses were used to measure changes in functional connectivity, with the right inferior frontal gyrus (IFG) a critical region for executive function. Patients on placebo had reduced connectivity relative to controls from right IFG to dorsal anterior cingulate cortex and to left IFG and dorsolateral prefrontal cortex. Atomoxetine increased connectivity from the right IFG to the dorsal anterior cingulate. In addition, the atomoxetine-induced change in connectivity from right IFG to dorsolateral prefrontal cortex was proportional to the change in verbal fluency, a simple index of executive function. The results support the hypothesis that atomoxetine may restore prefrontal networks related to executive functions. We suggest that task-free imaging can support translational pharmacological studies of new drug therapies and provide evidence for engagement of the relevant neurocognitive systems.

Network-selective vulnerability of the human cerebellum to Alzheimer's disease and frontotemporal dementia

SEE SCHMAHMANN DOI101093/BRAIN/AWW064 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: Neurodegenerative diseases are associated with distinct and distributed patterns of atrophy in the cerebral cortex. Emerging evidence suggests that these atrophy patterns resemble intrinsic connectivity networks in the healthy brain, supporting the network-based degeneration framework where neuropathology spreads across connectivity networks. An intriguing yet untested possibility is that the cerebellar circuits, which share extensive connections with the cerebral cortex, could be selectively targeted by major neurodegenerative diseases. Here we examined the structural atrophy in the cerebellum across common types of neurodegenerative diseases, and characterized the functional connectivity patterns of these cerebellar atrophy regions. Our results showed that Alzheimer's disease and frontotemporal dementia are associated with distinct and circumscribed atrophy in the cerebellum. These cerebellar atrophied regions share robust and selective intrinsic connectivity with the atrophied regions in the cerebral cortex. These findings for the first time demonstrated the selective vulnerability of the cerebellum to common neurodegenerative disease, extending the network-based degeneration framework to the cerebellum. Our work also has direct implications on the cerebellar contribution to the cognitive and affective processes that are compromised in neurodegeneration as well as the practice of using the cerebellum as reference region for ligand neuroimaging studies.

Incidence of metachronous visible lesions in patients referred for radiofrequency ablation (RFA) therapy for early Barrett's neoplasia: a single-centre experience

OBJECTIVE

Evaluate the incidence of metachronous visible lesions (VLs) in patients referred for radiofrequency ablation (RFA) for early Barrett's neoplasia.

DESIGN

This study was conducted as part of the service evaluation audit.

SETTING

Tertiary referral centre.

PATIENTS

All patients with dysplastic Barrett's oesophagus referred for RFA were included for analysis. White light high-resolution endoscopy (HRE), autofluorescence imaging and narrow band imaging were sequentially performed. Endoscopic mucosal resection (EMR) was performed for all VL. Three to six months after EMR, all patients underwent initial RFA and then repeat RFA procedures at three monthly intervals.

INTERVENTIONS

All endoscopy reports and final staging by EMR/surgery were evaluated and included for analysis.

RESULTS

Fifty patients were analysed; median age 73 years, 84% men. 38/50 patients (76%) had a previous EMR due to the presence of VL before referred for ablation; twelve patients had no previous treatment. In total, 151 ablation procedures were performed, median per patient 2.68. Twenty metachronous VL were identified in 14 patients before the first ablation or during the RFA protocol; incidence was 28%. All metachronous lesions were successfully resected by EMR. Upstaging after rescue EMR compared with the initial histology was observed in four patients (28%).

CONCLUSIONS

In total, 28% of patients enrolled in the RFA programme were diagnosed to have metachronous lesions. This high-incidence rate highlights the importance of a meticulous examination to identify and resect any VL before every ablation session. RFA treatment for early Barrett's neoplasia should be performed in tertiary referral centres with HRE and EMR facilities and expertise.

Graph network analysis of immediate motor-learning induced changes in resting state BOLD

Recent studies have demonstrated that following learning tasks, changes in the resting state activity of the brain shape regional connections in functionally specific circuits. Here we expand on these findings by comparing changes induced in the resting state immediately following four motor tasks. Two groups of participants performed a visuo-motor joystick task with one group adapting to a transformed relationship between joystick and cursor. Two other groups were trained in either explicit or implicit procedural sequence learning. Resting state BOLD data were collected immediately before and after the tasks. We then used graph theory-based approaches that include statistical measures of functional integration and segregation to characterize changes in biologically plausible brain connectivity networks within each group. Our results demonstrate that motor learning reorganizes resting brain networks with an increase in local information transfer, as indicated by local efficiency measures that affect the brain's small world network architecture. This was particularly apparent when comparing two distinct forms of explicit motor learning: procedural learning and the joystick learning task. Both groups showed notable increases in local efficiency. However, a change in local efficiency in the inferior frontal and cerebellar regions also distinguishes between the two learning tasks. Additional graph analytic measures on the "non-learning" visuo-motor performance task revealed reversed topological patterns in comparison with the three learning tasks. These findings underscore the utility of graph-based network analysis as a novel means to compare both regional and global changes in functional brain connectivity in the resting state following motor learning tasks.

Correlation between the presence of high-risk human papillomaviruses and Id gene expression in Syrian women with cervical cancer

Infection by high-risk human papillomaviruses (HPVs) is considered to be the central cause of invasive cervical cancer. Previously reported studies have shown that Id genes regulate cell invasion and metastasis in several human carcinomas including cervical cancer. In order to investigate the correlation between high-risk HPVs and Id genes in human cervical cancer, the presence of high-risk HPVs and their association with Id gene expression was examined using PCR methods and tissue microarray analyses in a cohort of 44 cervical cancer patients from Syria. This study showed that high-risk HPVs were present in 42 samples (95%) that represent invasive cervical cancers and that the most frequent high-risk HPV types in Syrian women were 33, 16, 18, 45, 52, 58, 35, 51 and 31. Furthermore, the expression of E6 oncoprotein of high-risk HPVs was found to correlate with overexpression of Id-1, but not of Id-2, Id-3 or Id-4 in the majority of invasive cervical cancer tissue samples. These data suggest that high-risk HPVs can enhance the progression of human cervical cancer through Id-1 regulation.

Imprint cytology of needle core-biopsy specimens of breast lesions: Is it a useful adjunt to rapid assessment breast clinics?

This study aimed at assessing the practicability of imprint cytology (IC) of core biopsy (CB) specimens in order to achieve one-stop diagnosis of breast lesions. In total, 199 symptomatic patients underwent free-hand CB of the suspected breast lesions. The slides were stained by Diff-QuikO and reported independently of histological reporting. For practical reasons cytology specimens were graded as follows: C1=inadequate, as less than 4 groups of epithelial cells were seen, C2=benign, C3=probably benign, C4=probably malignant and C5=positive for malignancy. The results of IC were correlated with CB histology. Absolute sensitivity of the IC was 85.0% and complete sensitivity was 89.2% when correlated with CB. Specificity (biopsy cases only) of IC was 53.1% while full specificity was 53.1%. Positive predictive value of C5 was 99.3%, C4 55.6 % and C3 was 100%. Overall suspicious rate was 5.5%. It was concluded that IC is a reliable way of diagnosing symptomatic breast lesions in one-stop breast clinic and retains the advantage of pre-operative availability of detailed pathological characteristics of tumours for treatment planning.

Randomized trial of effects of estradiol in combination with either norethisterone acetate or trimegestone on lipids and lipoproteins in postmenopausal women

OBJECTIVE

This double-blind, randomized, multicenter study was designed to compare the blood lipid profiles in postmenopausal women after treatment with either a combined formulation containing estradiol (2 mg) and trimegestone (TMG 0.25 or 0.5 mg) or a standard hormone therapy (HT) containing estradiol and norethisterone acetate.

METHOD

The serum concentrations of several lipids and lipoproteins were measured in this study, which was conducted over 13 cycles, each of 28 days. A total of 487 subjects were included, 349 of whom completed the study.

RESULTS

The circulating concentrations of high density lipoprotein (HDL) cholesterol, HDL2 cholesterol and apolipoprotein (apo) AI increased from baseline in both estradiol/trimegestone groups, whilst levels of HDL3 cholesterol were unchanged. In contrast, in the estradiol/norethisterone acetate group, HDL cholesterol, HDL3 cholesterol and apo AI concentrations were reduced from baseline, while HDL2 cholesterol remained unchanged. Total cholesterol, low density lipoprotein (LDL) cholesterol, lipoprotein(a) and apo-B concentrations were reduced in all treatment groups. The concentration of triglycerides was elevated after treatment with the estradiol/trimegestone combinations but was unchanged after treatment with the estradiol/norethisterone acetate combination. The differences in the lipid pattern between the groups may be explained by the different pharmacological properties of the two progestogens: norethisterone exerts an androgenic effect and opposes the estrogen-induced increase in HDL cholesterol, whilst trimegestone has no androgenic effect and does not oppose the estrogenic effect.

CONCLUSION

Overall, the results of this study suggest that the use of trimegestone in combination with estradiol may be preferable to norethisterone acetate because of the more favorable HDL and apo AI profile.

Acute myocardial infarction: profile and management at a tertiary care hospital in Karachi

OBJECTIVE

Acute Myocardial Infarction (AMI) is a rising epidemic in developing countries. While studies in the West have established the characteristics and management of AMI patients, comprehensive data reflecting these issues in the Pakistani subjects is scarce. This study examined the profile and management of AMI in patients hospitalized at a tertiary care hospital in Karachi, Pakistan.

METHODS

Three hundred forty four patients admitted in 1998 with the diagnosis of AMI met our inclusion criteria. Data on presentation, investigations, monitoring and therapy was obtained. Chi-square and t tests were used to analyze the data.

RESULTS

Out of 344 patients with AMI, 71% were males; 58% had a Q wave MI. Majority of the patients who presented within 2 hours of symptom onset (36%), had chest pain. Patients with dyspnea and no chest pain were more likely to present after 12 hours of the onset of symptoms. In-house mortality was found to be 10.8%. Low HDL and diabetes was associated with in-hospital complications. Twenty nine percent of patients were given thrombolytic therapy with a mean door-to-needle time of 1 hour 36 minutes; 33% of patients who were eligible of Streptokinase did not receive it. Cardiac catheterization was performed in 28% patients. Echocardiography and Exercise Tolerance Test, both under utilized, were performed in 67% and 16% of patients, respectively. Two hundred sixteen (70%) patients discharged from hospital were contacted via telephone and the 1-year mortality rate among them was 28%.

CONCLUSION

The profile and management of AMI was in coherence with earlier, Western studies. Chest pain units need to be established in the Emergency Room. Patients should be risk stratified prior to discharge. Public awareness regarding primary and secondary prevention and symptoms of AMI needs to be increased.

[Blood determination of benzathine-penicillin used in acute joint rheumatism prophylaxis]

Our actual work studies the effectiveness in vivo of the Benzathin penicillin that is realized on 88 subjects suffering from a stable rheumatic fever. It has shown that: The first hours after an intramuscular injection, the benzathin penicillin is found at an efficient concentration superior to 0.02 ug/ml at the level of the blood. The highest dose in the blood is obtained the first 24 hours. The amount of antibiotic at the level of the blood is very efficient during 4 weeks.

Infective endocarditis and septic embolization with Ochrobactrum anthropi: case report and review of literature

Ochrobactrum anthropi, previously known as CDC group Vd, is an aerobic, Gram-negative bacillus of low virulence that occasionally causes human infection. We describe a case of infective endocarditis with O. anthropi complicated by septic embolization. A review of all the literature reported cases of O. anthropi infection is presented and categorized into 'Central line related', 'Transplant related' and "Other pyogenic infections". Mortality appears to be related to the underlying disease state, rather than the organism.

Immune complex-mediated glomerulonephritis associated with bacterial kidney disease in the rainbow trout (Oncorhynchus mykiss)

Rainbow trout (Oncorhynchus mykiss) developed a post-infectious chronic membranous glomerulonephritis 15 months after they had been experimentally infected with Renibacterium salmoninarum. Histologically, peritubular and periglomerular fibrosis, hypercellular glomeruli with occluded Bowman's space, and partial or complete adhesion to Bowman's capsule were constant features. Electron microscopy revealed thickened glomerular basement membranes with spikes accompanied by finely granular electron-dense deposits at the epithelial side and dense material in the mesangial matrix. Indirect immunofluorescence indicated linear immunoglobulin deposits along the glomerular basement membrane. The presence of R. salmoninarum was demonstrated by culture and by indirect immunofluorescence. Low serum hemagglutination-inhibiting antibody titers were demonstrated.

Nutritional status and growth in juvenile rheumatoid arthritis

The specific cause of short stature in juvenile rheumatoid arthritis (JRA) is unknown. One hypothesis links altered growth to inadequate dietary intake. In this study, nutritional status was assessed in 34 children with JRA (8 with systemic JRA, 14 with polyarticular JRA, and 12 with pauciarticular JRA) and 9 healthy controls using 3-day diet records, anthropometrics, and biochemical analyses. Differences in growth were found among the three types of JRA. One third of all subjects were at or below the 10th percentile in height for age (these being predominantly among the systemic and polyarticular groups). With few exceptions, the mean dietary intake for calories and essential nutrients was found to be adequate for each of the three groups. However, more than half of those with systemic JRA reportedly consumed less than the recommended caloric intake for their age and weight. No significant correlations were found linking dietary intake to growth percentiles in any of the groups studied. Biochemical abnormalities were found among the systemic and polyarticular groups. These abnormalities included low plasma levels of vitamins A and C, proteins (albumin, prealbumin, and retinol binding protein) and zinc; and increased levels of copper and glutathione peroxidase activity. Plasma selenium and vitamin E levels were unchanged. The discrepancy between intake and certain circulating nutrient levels may reflect alterations in the requirements, absorption, or use of these nutrients in the presence of chronic inflammation.

Low molecular weight immunosuppressive factors found in elevated amounts in cancer ascitic fluids of mice. 1. Isolation, identification and immunosuppressive effects of uric acid and uracil

A definite increase in two low molecular weight factors, G10-2 and G10-3 was found in Ehrlich ascitic fluids, parallel to tumor growth. The isolation and identification of the two factors were attempted through gel filtration and reversed phase column chromatography, using ascitic fluids obtained 13 days after intraperitoneal implantation of Ehrlich tumor cells. As a result, two highly purified factors were observed upon examination by high performance liquid chromatography. Additional analytical data, collected by UV spectrum, NMR spectrum and mass analysis, allowed us to identify G10-2 as uric acid and G10-3 as uracil. Detailed immunological analysis of uric acid and uracil revealed that the augmenting activities of mouse and human NK cells by mouse IFN alpha/beta or human rIFN alpha A/D were impaired in the presence of either compound at concentrations of 0.07 mM, the concentration detectable in the ascitic fluid of tumor bearing mice.

Low molecular weight immunosuppressive factors found in elevated amounts in cancer ascitic fluids of mice. 2. 1-Methyladenosine isolated from cancer ascitic fluids enhances Listeria infection in mice

The low molecular weight fraction (mol wt less than 1,000) of Ehrlich cancer ascitic fluid has been known to enhance Listeria infection in mice. Chemical characterization of the entities in this fraction revealed four purine and pyrimidine analogues, i.e. uric acid, uracil, pseudouridine and 1-methyladenosine (m1Ado). When the effect of each of these components was studied on Listeria infection in mice, only m1Ado markedly enhanced the infection and killed the mice within a short period. The optimal enhancement was obtained when m1Ado was given intravenously to mice 3-6 days before the infection at a concentration of between 1 and 100 micrograms/mouse. On the other hand, uric acid, uracil and pseudouridine failed to show such an enhancing effect. m1Ado inhibited macrophage accumulation in the peritoneal cavity of mice after an intraperitoneal injection of phytohemagglutinin. Although m1Ado did not show any inhibitory effect on the phagocytic and bactericidal activities of macrophages in vitro, peritoneal macrophages obtained from mice which received m1Ado 3 days ahead revealed impaired bactericidal activity, suggesting the migration of different cell populations from the bone marrow of m1Ado-receiving mice. The results may suggest that m1Ado is a major factor in tumor ascites causing, in small doses, an impairment of macrophage functioning as can be detected in tumor-bearing hosts.