Impact of distinct cognitive domains on gait variability in individuals with mild cognitive impairment and dementia.

BACKGROUND: Gait variability is a common feature in neurodegenerative diseases and has been linked to cognitive impairment. Despite this link, the influence of specific cognitive domains, such as memory, visual spatial skills, executive function, and verbal function on gait variability is not well-understood. OBJECTIVE: To investigate the predictive value of these specific cognitive domains on gait variability in people with mild cognitive impairment (MCI) and dementia during preferred and dual task walking. METHOD: One hundred and two participants with either MCI or dementia underwent a comprehensive cognitive assessment and completed preferred and dual-task walking trials on a pressure-sensing walkway. Gait variability was assessed using the PKMAS software. Lower extremity function was evaluated with a self-reported validated scale. RESULTS: Our findings indicate that only visual spatial abilities had a moderate predictive value on gait variability [F (1, 78) = 17.30, p < 0.01, r = 0.43], both in preferred pace walking (70% direct effect) and dual-task walking (90% direct effect) (p's < 0.05). Additionally, lower extremity functional skills had a significant indirect effect (30%) on gait variability in preferred walking contexts. CONCLUSION: For individuals diagnosed with MCI or dementia, increased gait variability may be driven by deficits in visual spatial processing. An increased understanding of the role of visual spatial processing in gait variability can aid in the assessment and management of individuals with MCI or dementia, potentially leading to targeted interventions to improve mobility and safety.

A proposed new taxonomy of cognitive phenotypes in multiple sclerosis: The International Classification of Cognitive Disorders in MS (IC-CoDiMS).

BACKGROUND: Characterization of cognitive impairment (CI) in multiple sclerosis into distinct phenotypes holds promise for individualized treatments and biomarker exploration. OBJECTIVE: Apply a previously validated, neuropsychologically driven diagnostic algorithm to identify a taxonomy of the type of cognitive phenotypes in multiple sclerosis. METHODS: An algorithm developed and validated in other neurological diseases was applied to a cohort of 1281 people with multiple sclerosis who underwent clinical neuropsychological evaluation across three multiple sclerosis centers. A domain was marked impaired if scores on two tests within the domain fell below one of the two thresholds of interest (compared to controls; -1.0 SD and -1.5 SD below the mean). Results were then tabulated for each participant to determine the type of impairments across the sample. RESULTS: At -1 SD threshold, 48.7% were intact, 21.6% had single-domain, 14.3% bi-domain, and 15.4% multi-domain impairment. At -1.5 SD threshold, 72.9% were intact, 14.0% had single-domain, 8.2% bi-domain, and 5.0% multi-domain impairment. Processing speed was the most frequent single-domain impairment, followed by executive function and memory. CONCLUSIONS: These findings advance the taxonomy of cognitive phenotypes in multiple sclerosis and clarify the type and distribution of possible cognitive diagnoses, pave the way for further investigation of associated biomarkers, and provide clinically meaningful information to guide individualized treatment and rehabilitation.

Effect of Neurotoxin Exposure on Blood Biomarkers of Neurodegeneration and Alzheimer Disease.

AIM: To determine whether exposure to neurotoxins in midlife is associated with changes in blood-based biomarkers of neurodegeneration and Alzheimer disease pathology. METHODS: Blood cadmium, lead, neurofilament light (NfL) chain, total tau (TTau), and amyloid beta (Aß) 40 and Aß42 concentrations were measured in 1516 participants in the Beaver Dam Offspring Study. Linear mixed-effect models were used to determine associations between baseline cadmium and lead levels and baseline NfL, TTau, and Aß42/Aß40, and 10-year change in concentrations using repeated measures of these biomarkers as the outcome. RESULTS: In women, higher cadmium and lead levels were associated with higher baseline TTau concentrations. A higher baseline cadmium level was associated with lower baseline Aß42/Aß40 in both men and women. In age-sex-adjusted models, a doubling in baseline cadmium level was associated with a 0.2% (95% CI: 0.0, 0.3) higher increase per year in NfL concentrations. In men, a doubling of baseline lead level was associated with a 0.9% (95% CI: 0.1, 1.7) higher increase per year in TTau concentration. CONCLUSIONS: Participants with relatively higher levels of cadmium and lead had blood biomarker concentrations consistent with more neuronal damage and Alzheimer disease pathology. Environmental exposure to neurotoxins may contribute to neurodegeneration.

SupportiNg operAtive Photographic documentation in ileocolonic CROHN's disease surgery: The SNAPCROHN study.

BACKGROUND: There are reported variations in the intraoperative management of Crohn's disease. This consensus statement aimed to develop a standardised protocol for photographic documentation of intraoperative findings and critical procedural steps in ileocolonic Crohn's disease surgery. METHODS: Colorectal surgeons with a specialist interest in minimally invasive surgery and inflammatory bowel disease were invited as committee members to develop a survey on the use of photo-documentation in Crohn's disease surgery. A 15 item survey was developed on ethical considerations and applications of photo-documentation in audit and quality control, research, and training. RESULTS: There was strong agreement on the potential application of intraoperative photo-documentation in Crohn's disease for training, research, quality control and tertiary referrals. Reviewers agreed that intraoperative staging required photo-documentation of strictures, skip lesions, perforations, fat wrapping and mesenteric disease. The necessary steps to be photo-documented were very specific to Crohn's disease surgery, such as views of anastomosis and strictureplasties, and extent of resection(s). CONCLUSIONS: Our consensus statement identified several items for appropriate intraoperative photo-documentation in Crohn's disease surgery, to be used as an adjunct to accurate annotation of intraoperative findings and procedures.

The pupil constriction to light is associated with cognitive measures in middle-aged and older adults.

AIMS: The evidence relating the pupil light reflex (PLR) and cognition have been inconsistent. In this cross-sectional study, we evaluated the association between the PLR and cognition in community-dwelling middle-aged and older individuals. METHODS: Pupil reactivity was recorded in a subgroup of 403 participants (mean age 60.7 years, 57.3% females) in an epidemiologic study of aging. Ten pupil parameters were calculated to describe pupil constriction to light stimuli. A principal component analysis (PCA) score was used to calculate an overall performance over four cognitive testings. Linear regression was used to assess the association between pupil parameters and PCA scores, adjusting for age, sex, education, medications, health-related quality of life questionnaire, and systemic and ocular comorbidities. RESULTS: The PCA scores decreased by 0.039 [95% CI (- 0.050, - 0.028)] per year increase in age and were lower in males than females by 0.76 [95% CI (- 0.96, - 0.55)] (p < 0.001). Pupil constriction amplitude in millimeters and the duration from stimulus onset to maximal constriction velocity were significantly associated with cognition after adjusting for (1) age and sex and (2) age, sex, and multiple covariates (p < 0.05). CONCLUSIONS: In this study, we provided moderate evidence suggesting the association between PLR and neuropsychological cognitive measures. The findings suggest the potential of pupil reactivity to serve as a biomarker of brain aging and warrant further longitudinal study to assess if changes in the PLR can predict cognitive decline over time.

Joint ACPGBI and The Duke's Club statement on colonoscopy training.

Colorectal surgeons across the UK currently undertake a large proportion of routine diagnostic and therapeutic colonoscopy in most NHS Trusts [1]. Meanwhile, the new UK General Surgical curriculum now includes an indicative requirement of 200 diagnostic colonoscopies for surgical trainees who have declared a colorectal subspecialty interest (hereafter termed 'colorectal trainees'), indicating the JCST's (Joint Committee on Surgical Training) commitment to colonoscopy training. However, several studies have reported a marked deficiency in colonoscopy training opportunities and accreditation for surgical trainees compared with gastroenterology trainees [2-4].

Adaptations to the British Society of Gastroenterology guidelines on the management of acute severe UC in the context of the COVID-19 pandemic: a RAND appropriateness panel.

OBJECTIVE: Management of acute severe UC (ASUC) during the novel COVID-19 pandemic presents significant dilemmas. We aimed to provide COVID-19-specific guidance using current British Society of Gastroenterology (BSG) guidelines as a reference point. DESIGN: We convened a RAND appropriateness panel comprising 14 gastroenterologists and an IBD nurse consultant supplemented by surgical and COVID-19 experts. Panellists rated the appropriateness of interventions for ASUC in the context of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. Median scores and disagreement index (DI) were calculated. Results were discussed at a moderated meeting prior to a second survey. RESULTS: Panellists recommended that patients with ASUC should be isolated throughout their hospital stay and should have a SARS-CoV-2 swab performed on admission. Patients with a positive swab should be discussed with COVID-19 specialists. As per BSG guidance, intravenous hydrocortisone was considered appropriate as initial management; only in patients with COVID-19 pneumonia was its use deemed uncertain. In patients requiring rescue therapy, infliximab with continuing steroids was recommended. Delaying colectomy because of COVID-19 was deemed inappropriate. Steroid tapering as per BSG guidance was deemed appropriate for all patients apart from those with COVID-19 pneumonia in whom a 4-6 week taper was preferred. Post-ASUC maintenance therapy was dependent on SARS-CoV-2 status but, in general, biologics were more likely to be deemed appropriate than azathioprine or tofacitinib. Panellists deemed prophylactic anticoagulation postdischarge to be appropriate in patients with a positive SARS-CoV-2 swab. CONCLUSION: We have suggested COVID-19-specific adaptations to the BSG ASUC guideline using a RAND panel.

Effects of maternal source and progeny microhabitat on natural selection and population dynamics in Alliaria petiolata.

PREMISE: The success or failure of propagules in contrasting microhabitats may play a role in biological invasion. We tested for variation in demographic performance and phenotypic trait expression during invasion by Alliaria petiolata in different microhabitats. METHODS: We performed a reciprocal transplant experiment with Alliaria petiolata from edge, intermediate, and forest understory microhabitats to determine the roles of the environment and maternal source on traits, fecundity, population growth rates (λ), and selection. RESULTS: Observations of in situ populations show that edge populations had the highest density and reproductive output, and forest populations had the lowest. In experimental populations, population growth rates and reproductive output were highest in the edge, and the intermediate habitat had the lowest germination and juvenile survival. Traits exhibited phenotypic plasticity in response to microhabitat, but that plasticity was not adaptive. There were few effects of maternal source location on fitness components or traits. CONCLUSIONS: Alliaria petiolata appears to be viable, or nearly so, in all three microhabitat types, with edge populations likely providing seed to the other microhabitats. The intermediate microhabitat may filter propagules at the seed stage, but discrepancies between in situ observations and experimental transplants preclude clear conclusions about the role of each microhabitat in niche expansion. However, edge microhabitats show the highest seed output in both analyses, suggesting that managing edge habitats might reduce spread to the forest understory.

The relationship between complement C3 expression and the MUC5B genotype in pulmonary fibrosis.

The common gain-of-function MUC5B promoter variant ( rs35705950 ) is the strongest risk factor for the development of idiopathic pulmonary fibrosis (IPF). While the role of complement in IPF is controversial, both MUC5B and the complement system play a role in lung host defense. The aim of this study was to evaluate the relationship between complement component 3 (C3) and MUC5B in patients with IPF and in bleomycin-induced lung injury in mice. To do this, we evaluated C3 gene expression in whole lung tissue from 300 subjects with IPF and 175 healthy controls. Expression of C3 was higher in IPF than healthy controls {1.40-fold increase [95% confidence interval (CI) 1.31-1.50]; P < 0.0001} and even greater among IPF subjects with the highest-risk IPF MUC5B promoter genotype [TT vs. GG = 1.59-fold (95% CI 1.15-2.20); P < 0.05; TT vs. GT = 1.66-fold (95% CI 1.20-2.30); P < 0.05]. Among subjects with IPF, C3 expression was significantly higher in the lung tissue without microscopic honeycombing than in the lung tissue with microscopic honeycombing [1.40-fold increase (95% CI 1.23- 1.59); P < 0.01]. In mice, while bleomycin exposure increased Muc5b protein expression, C3-deficient mice were protected from bleomycin-induced lung injury. In aggregate, our findings indicate that the MUC5B promoter variant is associated with higher C3 expression and suggest that the complement system may contribute to the pathogenesis of IPF.

Northern ragweed ecotypes flower earlier and longer in response to elevated CO2: what are you sneezing at?

Significant changes in plant phenology and flower production are predicted over the next century, but we know relatively little about geographic patterns of this response in many species, even those that potentially impact human wellbeing. We tested for variation in flowering responses of the allergenic plant, Ambrosia artemisiifolia (common ragweed). We grew plants originating from three latitudes in the Northeastern USA at experimental levels of CO2 (400, 600, and 800 µL L(-1)). We hypothesized that northern ecotypes adapted to shorter growing seasons would flower earlier than their southern counterparts, and thus disproportionately allocate carbon gains from CO2 to reproduction. As predicted, latitude of origin and carbon dioxide level significantly influenced the timing and magnitude of flowering. Reproductive onset occurred earlier with increasing latitude, with concurrent increases in the number of flowers produced. Elevated carbon dioxide resulted in earlier reproductive onset in all ecotypes, which was significantly more pronounced in the northern populations. We interpret our findings as evidence for ecotypic variation in ragweed flowering time, as well in responses to CO2. Thus, the ecological and human health implications of common ragweed's response to global change are likely to depend on latitude. We conclude that increased flower production, duration, and possibly pollen output, can be expected in Northeastern United States with rising levels of CO2. The effects are likely, however, to be most significant in northern parts of the region.

Internal dressings for healing perianal abscess cavities.

BACKGROUND: A perianal abscess is a collection of pus under the skin, around the anus. It usually occurs due to an infection of an anal gland. In the UK, the annual incidence is 40 per 100,000 of the adult population, and the standard treatment is admission to hospital for incision and drainage under general anaesthetic. Following drainage of the pus, an internal dressing (pack) is placed into the cavity to stop bleeding. Common practice is for community nursing teams to change the pack regularly until the cavity heals. Some practitioners in the USA and Australia make a small stab incision under local anaesthetic and place a catheter into the cavity which drains into an external dressing. It is removed when it stops draining. Elsewhere in the USA, simple drainage is performed in an outpatient setting under local anaesthetic. OBJECTIVES: To assess the effects of internal dressings in healing wound cavities resulting from drainage of perianal abscesses. SEARCH METHODS: In May 2016 we searched: The Cochrane Wounds Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE and EBSCO CINAHL Plus. We also searched clinical trial registries to identify ongoing and unpublished studies, and searched reference lists of relevant reports to identify additional studies. We did not restrict studies with respect to language, date of publication, or study setting. SELECTION CRITERIA: Published or unpublished randomised controlled trials (RCTs) comparing any type of internal dressing (packing) used in the post-operative management of perianal abscess cavities with alternative treatments or different types of internal dressing. DATA COLLECTION AND ANALYSIS: Two review authors independently performed study selection, risk of bias assessment, and data extraction. MAIN RESULTS: We included two studies, with a total of 64 randomised participants (50 and 14 participants) aged 18 years or over, with a perianal abscess. In both studies, participants were enrolled on the first post-operative day and randomised to continued packing by community district nursing teams or to no packing. Participants in the non-packing group managed their own wounds in the community and used absorbant dressings to cover the area. Fortnightly follow-up was undertaken until the cavity closed and the skin re-epithelialised, which constituted healing. For non-attenders, telephone follow-up was conducted.Both studies were at high risk of bias due to risk of attrition, performance and detection bias.It was not possible to pool the two studies for the outcome of time to healing. It is unclear whether continued post-operative packing of the cavity of perianal abscesses affects time to complete healing. One study reported a mean time to wound healing of 26.8 days (95% confidence interval (CI) 22.7 to 30.7) in the packing group and 19.5 days (95% CI 13.6 to 25.4) in the non-packing group (it was not clear if all participants healed). We re-analysed the data and found no clear difference in the time to healing (7.30 days longer in the packing group, 95% CI -2.24 to 16.84; 14 participants). This was assessed as very low quality evidence (downgraded three levels for very serious imprecision and serious risk of bias). The second study reported a median time to complete wound healing of 24.5 days (range 10 to 150 days) in the packing group and 21 days (range 8 to 90 days) in the non-packed group. There was insufficient information to be able to recreate the analysis and the original analysis was inappropriate (did not account for censoring). This second study also provided very low quality evidence (downgraded four levels for serious risk of bias, serious indirectness and very serious imprecision).There was very low quality evidence (downgraded for risk of bias, indirectness and imprecision) of no difference in wound pain scores at the initial dressing change. Both studies also reported patients' retrospective judgement of wound pain over the preceding two weeks (visual analogue scale, VAS) as lower for the non-packed group (2; both studies) compared with the packed group (0; both studies); (very low quality evidence) but we have been unable to reproduce these analyses as no variance data were published.There was no clear evidence of a difference in the number of post-operative fistulae detected between the packed and non-packed groups (risk ratio (RR) 2.31, 95% CIs 0.56 to 9.45, I(2) = 0%) (very low quality evidence downgraded three levels for very serious imprecision and serious risk of bias).There was no clear evidence of a difference in the number of abscess recurrences between the packed and non-packed groups over the variable follow-up periods (RR 0.72, 95% CI 0.22 to 2.37, I(2) = 0%) (very low quality evidence downgraded three levels for serious risk of bias and very serious imprecision).No study reported participant health-related quality of life/health status, incontinence rates, time to return to work or normal function, resource use in terms of number of dressing changes or visits to a nurse, or change in wound size. AUTHORS' CONCLUSIONS: It is unclear whether using internal dressings (packing) for the healing of perianal abscess cavities influences time to healing, wound pain, development of fistulae, abscess recurrence or other outcomes. Despite this absence of evidence, the practice of packing abscess cavities is commonplace. Given the lack of high quality evidence, decisions to pack may be based on local practices or patient preferences. Further clinical research is needed to assess the effects and patient experience of packing.

Associations Between Cognitive Impairment and Neuroimaging in Patients with Multiple Sclerosis.

OBJECTIVE: Multiple sclerosis (MS) is a debilitating inflammatory and neurodegenerative disease which commonly involves cognitive dysfunction. Magnetic resonance imaging (MRI) studies have shown that patients with MS (pwMS) have diffuse patterns of brain atrophy, however, the relationship between the presentation of cognitive dysfunction and brain tissue loss remains understudied. Given the integral function of thalamus as a central nervous system relay center and its involvement in various brain circuits, thalamic atrophy may play a key role in the development and progression of cognitive dysfunction. The purpose of this study is to examine the relationship between cognitive impairment in pwMS and thalamic atrophy. METHODS: A total of 121 pwMS who had neuropsychological testing and quantitative MRI within 1 year of each were retrospectively identified. Grouped LASSO linear regression with 10-fold cross validation was used to estimate each neuropsychological test score with thalamic volume as the focal predictor and all other demographic and MRI metrics as covariates. RESULTS: Rates of impairment ranged from 19% to 44%. Results showed notable associations between thalamic volume and Symbol Digit Modalities Test (ß = 0.11), Brief Visuospatial Memory Test, delayed (ß = 0.12), California Verbal Learning Test, delayed and total (ß = 0.24 and ß = 0.15 respectively), and Trail Making Test Part A (ß = -0.01), after adjusting for covariates. CONCLUSIONS: These findings demonstrate an independent association between thalamic volumes and processing speed and memory performance, after accounting for demographic, clinical, and other MRI variables, among pwMS.

Comparing Cognitive Profiles in Older Adults With Multiple Sclerosis and Alzheimer Disease: More Similarities Than Differences.

Background and Objectives: Up to 65% of people with multiple sclerosis (MS) experience disease-related cognitive impairment, but even after decades of research, still very little is known about the cognitive issues among older adults with MS (EwMS; individuals aged 60+). To date, few studies have attempted to characterize cognitive impairment in this group or compare EwMS with those with other neurodegenerative diseases. Our goal was to address this knowledge gap by comparing EwMS with individuals experiencing cognitive impairment due to probable Alzheimer disease (AD) with biomarker confirmation. Methods: We conducted an observational study of individuals seen for routine clinical care at the Cleveland Clinic. After excluding for potential confounding factors, 6 groups were assembled based on the results of their clinical workup and neuropsychological examination: cognitively normal, cognitively normal with MS, mild neurocognitive disorder (due to MS or AD), and major neurocognitive disorder (due to MS or AD). These groups were compared in terms of cognitive test performance, percentage of the group impaired on specific cognitive skills, and rates of cognitive impairment. Results: The sample comprised 140 individuals (64 EwMS and 76 demographically matched individuals from a memory clinic). Among those with mild neurocognitive disorder, differences between MS and AD were marked. However, in those with major neurocognitive disorder, these differences largely disappeared, except persistent performance differences on a measure of rote verbal memory. EwMS outperformed those with AD on memory tests at each level of cognitive impairment. EwMS also exhibited both subcortical and cortical deficits, rather than solely subcortical deficits. Discussion: The overall characterization of the cognitive profile of MS may be different than once described, involving both classically cortical and subcortical functions. Clinically, our results suggest that distinguishing between the cognitive effects of MS and AD at more severe levels of cognitive impairment may be less reliable than once thought. Future work to replicate these findings in other samples and deepen the understanding of cognition in older individuals with MS is needed.