Oxidation Activity of Catalyst 3-7A Toward Formaldehyde, Hydrogen Cyanide, And Some Alkane Gases

The activity of Catalyst 3-7A toward the oxidation of formaldehyde, hydrogen cyanide, methane, propane, and isobutene was examined at temperatures between 25°C and 400°C. The catalyst consists of palladium(II) and copper (II) salts impregnated on an alumina support. The oxidation measurements were made primarily with gas chromatographs, although form aldehyde and hydrogen cyanide were also examined using the colorimetric fushsin method and Liebig titrations, respectively. Catalyst 3-7A demonstrated appreciable activity toward the oxidation of all gases studied except formaldehyde where there was no evidence of oxidation. The latter result is quite unexpected since aldehydes are more easily oxidized than alkanes. It is suggested that the inactivity of Catalyst 3-7A toward formaldehyde is attributed to the lack of moisture which is required by the catalyst during oxidation. All oxidation reactions are believed to occur via a Qacker-type process under pseudo-first order conditions with the palladium(II) concentration maintained constant via the presence of copper (II) which oxidizes metallic palladium, the product in the oxidation reaction. The oxidation products in all the gases examined are believed to be carbon dioxide and water except for hydrogen cyanide where an additional product containing nitrogen should be formed but could not be detected with the gas chromatograph. Rate constants (reported in parenthesis) at 400°C for the following gases are hydrogen cyanide (\u3e26.2 sec-1), methane (6.5-6.6 sec-1), propane (\u3e12.8 sec-1), and isobutene (\u3e15.7 sec-1). These results show that hydrogen cyanide is the most active gas to be oxidized by the catalyst excluding carbon monoxide which is the test gas used I our system and has been previously determined to demonstrate the greatest activity with the catalyst. The three alkane gases show an order of oxidation reactivity which lends some support for ruling out an anionic mechanism since tertiary C-H bonds were found to be more reactive than secondary C-H bonds which in turn were shown to be more reactive than primary C-H bonds. A comparison of Catalyst 3-7A with other catalysts reported in the literature which show similar oxidation behavior with gases could not be made due to lack of data regarding their experimental conditions

Vancomycin therapy in critically ill patients on continuous renal replacement therapy; are we doing enough?

AbstractBackgroundRecommendations regarding vancomycin dosing and monitoring in critically ill patients on continuous renal replacement therapy (CRRT) are limited. This is a retrospective study to assess the adequacy of current vancomycin dosing and monitoring practice for patients on CRRT in a tertiary hospital in Riyadh, Saudi Arabia.MethodsA retrospective chart review of adult patients admitted between 1 April 2011 and 30 March 2013 to critical care and received intravenous vancomycin therapy whilst on CRRT was performed.ResultsA total of 68 patients received intravenous vancomycin therapy whilst on CRRT, of which 32 met the inclusion criteria. Fifty-one percent were males and median (range) age was 62.5 (19 – 90) years. Median APACHE II score was 33.5 (22–43) and median Charlson Comorbidity Score was 4 (0–8). The mean (±standard deviation) dose of vancomycin was 879.9mg (±281.2mg) for an average duration of 5.9days (±3.7days). All patients received continuous veno-venous haemofiltration (CVVH). A total of 55 vancomycin level readings were available from the study population, ranging from 6.6 to 41.3, with wide variations within the same sampling time frames. Vancomycin levels of>15mg/L or were achieved at least once in 24 patients (75.0%), but only 11 patients (34.3%) had 2 or more serum vancomycin level readings of 15mg/L or more.ConclusionTherapeutic vancomycin levels are difficult to maintain in critically ill patients who are receiving IV vancomycin therapy whilst on CRRT. Aggressive dosing schedules and frequent monitoring are required to ensure adequate vancomycin therapy in this setting

Shorter Telomeres May Mark Early Risk of Dementia: Preliminary Analysis of 62 Participants from the Nurses' Health Study

Background: Dementia takes decades to develop, and effective prevention will likely require early intervention. Thus, it is critical to identify biomarkers of preclinical disease, allowing targeting of high-risk subjects for preventive efforts. Since telomeres shorten with age and oxidative stress both of which are important contributors to the onset of dementia, telomere length might be a valuable biomarker. Methodology/Principal Findings: Among 62 participants of the Nurses' Health Study,we conducted neurologic evaluations, including patient and caregiver interviews physical exam, neurologic exam and neuropsychologic testing. We also conducted magnetic resonance imaging (MRI) in a sample of 29 of these women. In these preliminary data, after adjustment for numerous health and lifestyle factors, we found that truncated telomeres in peripheral blood leukocytes segregate with preclinical dementia states, including mild cognitive impairment (MRI); the odds of MCI were 12 fold higher (odds ratio = 12.00, 95% confidence interval 1.24-116.5) for those with shorter telomere length compared to longer telomere length. In addition, decreasing telomere length was strongly related to decreasing hippocampal volume (p=0.038). Conclusions: These preliminary data suggest that telomere length may be a possible early marker of dementia risk, and merits further study in large, prospective investigations

ICC-dementia (International Centenarian Consortium - dementia): an international consortium to determine the prevalence and incidence of dementia in centenarians across diverse ethnoracial and sociocultural groups.

BACKGROUND: Considerable variability exists in international prevalence and incidence estimates of dementia. The accuracy of estimates of dementia in the oldest-old and the controversial question of whether dementia incidence and prevalence decline at very old age will be crucial for better understanding the dynamics between survival to extreme old age and the occurrence and risk for various types of dementia and comorbidities. International Centenarian Consortium - Dementia (ICC-Dementia) seeks to harmonise centenarian and near-centenarian studies internationally to describe the cognitive and functional profiles of exceptionally old individuals, and ascertain the trajectories of decline and thereby the age-standardised prevalence and incidence of dementia in this population. The primary goal of the ICC-Dementia is to establish a large and thorough heterogeneous sample that has the power to answer epidemiological questions that small, separate studies cannot. A secondary aim is to examine cohort-specific effects and differential survivorship into very old age. We hope to lay the foundation for further investigation into risk and protective factors for dementia and healthy exceptional brain ageing in centenarians across diverse ethnoracial and sociocultural groups. METHODS: Studies focusing on individuals aged ≥95 years (approximately the oldest 1 percentile for men, oldest 5th percentile for women), with a minimum sample of 80 individuals, including assessment of cognition and functional status, are invited to participate. There are currently seventeen member or potential member studies from Asia, Europe, the Americas, and Oceania. Initial attempts at harmonising key variables are in progress. DISCUSSION: General challenges facing large, international consortia like ICC-Dementia include timely and effective communication among member studies, ethical and practical issues relating to human subject studies and data sharing, and the challenges related to data harmonisation. A specific challenge for ICC-Dementia relates to the concept and definition of'abnormal' in this exceptional group of individuals who are rarely free of physical, sensory and/or cognitive impairments

Limbic-predominant age-related TDP-43 encephalopathy (LATE): consensus working group report.

We describe a recently recognized disease entity, limbic-predominant age-related TDP-43 encephalopathy (LATE). LATE neuropathological change (LATE-NC) is defined by a stereotypical TDP-43 proteinopathy in older adults, with or without coexisting hippocampal sclerosis pathology. LATE-NC is a common TDP-43 proteinopathy, associated with an amnestic dementia syndrome that mimicked Alzheimer's-type dementia in retrospective autopsy studies. LATE is distinguished from frontotemporal lobar degeneration with TDP-43 pathology based on its epidemiology (LATE generally affects older subjects), and relatively restricted neuroanatomical distribution of TDP-43 proteinopathy. In community-based autopsy cohorts, ∼25% of brains had sufficient burden of LATE-NC to be associated with discernible cognitive impairment. Many subjects with LATE-NC have comorbid brain pathologies, often including amyloid-β plaques and tauopathy. Given that the 'oldest-old' are at greatest risk for LATE-NC, and subjects of advanced age constitute a rapidly growing demographic group in many countries, LATE has an expanding but under-recognized impact on public health. For these reasons, a working group was convened to develop diagnostic criteria for LATE, aiming both to stimulate research and to promote awareness of this pathway to dementia. We report consensus-based recommendations including guidelines for diagnosis and staging of LATE-NC. For routine autopsy workup of LATE-NC, an anatomically-based preliminary staging scheme is proposed with TDP-43 immunohistochemistry on tissue from three brain areas, reflecting a hierarchical pattern of brain involvement: amygdala, hippocampus, and middle frontal gyrus. LATE-NC appears to affect the medial temporal lobe structures preferentially, but other areas also are impacted. Neuroimaging studies demonstrated that subjects with LATE-NC also had atrophy in the medial temporal lobes, frontal cortex, and other brain regions. Genetic studies have thus far indicated five genes with risk alleles for LATE-NC: GRN, TMEM106B, ABCC9, KCNMB2, and APOE. The discovery of these genetic risk variants indicate that LATE shares pathogenetic mechanisms with both frontotemporal lobar degeneration and Alzheimer's disease, but also suggests disease-specific underlying mechanisms. Large gaps remain in our understanding of LATE. For advances in prevention, diagnosis, and treatment, there is an urgent need for research focused on LATE, including in vitro and animal models. An obstacle to clinical progress is lack of diagnostic tools, such as biofluid or neuroimaging biomarkers, for ante-mortem detection of LATE. Development of a disease biomarker would augment observational studies seeking to further define the risk factors, natural history, and clinical features of LATE, as well as eventual subject recruitment for targeted therapies in clinical trials.Sally Hunter and Carol Brayne are supported by funding from the National Institute for Health Research, Senior Investigator Award, awarded to Carol Brayne. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care. Sally Hunter is supported by the Addenbrooke’s Charitable Trust, the Paul G. Allen Family Foundation and Alzheimer’s Research, UK. Suvi Hokkanen was supported by Alzheimer’s Research, UK

Hormone-Dependent Aging Problems in Women

One of the major social issues nowadays is the aging society. Korea is already an aging society, and 63 cities and districts are ultra-aged societies where the rate of people older than 65 yr exceeds 20%. Among them, more than 67% are women. These statistics reveal the importance of healthcare for older women. Disease and disability of older women are very closely related to the loss of female sex hormones after menopause. Major hormone-dependent aging problems in women such as osteoporosis, Alzheimer's disease (AD), urinary incontinence, and coronary atherosclerosis were surveyed in this review, and the key role of hormones in those diseases and hormone replacement therapy (HRT) were summarized. We expect that this review would provide some understanding of factors that must be considered to give optimal care to older women for healthy lives

Limbic-Predominant Age-Related TDP-43 Encephalopathy (LATE): Consensus Working Group Report

We describe a recently recognized disease entity, limbic-predominant age-related TDP-43 encephalopathy (LATE). LATE neuropathological change (LATE-NC) is defined by a stereotypical TDP-43 proteinopathy in older adults, with or without coexisting hippocampal sclerosis pathology. LATE-NC is a common TDP-43 proteinopathy, associated with an amnestic dementia syndrome that mimicked Alzheimer’s-type dementia in retrospective autopsy studies. LATE is distinguished from frontotemporal lobar degeneration with TDP-43 pathology based on its epidemiology (LATE generally affects older subjects), and relatively restricted neuroanatomical distribution of TDP-43 proteinopathy. In community-based autopsy cohorts, ∼25% of brains had sufficient burden of LATE-NC to be associated with discernible cognitive impairment. Many subjects with LATE-NC have comorbid brain pathologies, often including amyloid-β plaques and tauopathy. Given that the ‘oldest-old’ are at greatest risk for LATE-NC, and subjects of advanced age constitute a rapidly growing demographic group in many countries, LATE has an expanding but under-recognized impact on public health. For these reasons, a working group was convened to develop diagnostic criteria for LATE, aiming both to stimulate research and to promote awareness of this pathway to dementia. We report consensus-based recommendations including guidelines for diagnosis and staging of LATE-NC. For routine autopsy workup of LATE-NC, an anatomically-based preliminary staging scheme is proposed with TDP-43 immunohistochemistry on tissue from three brain areas, reflecting a hierarchical pattern of brain involvement: amygdala, hippocampus, and middle frontal gyrus. LATE-NC appears to affect the medial temporal lobe structures preferentially, but other areas also are impacted. Neuroimaging studies demonstrated that subjects with LATE-NC also had atrophy in the medial temporal lobes, frontal cortex, and other brain regions. Genetic studies have thus far indicated five genes with risk alleles for LATE-NC: GRN, TMEM106B, ABCC9, KCNMB2, and APOE. The discovery of these genetic risk variants indicate that LATE shares pathogenetic mechanisms with both frontotemporal lobar degeneration and Alzheimer’s disease, but also suggests disease-specific underlying mechanisms. Large gaps remain in our understanding of LATE. For advances in prevention, diagnosis, and treatment, there is an urgent need for research focused on LATE, including in vitro and animal models. An obstacle to clinical progress is lack of diagnostic tools, such as biofluid or neuroimaging biomarkers, for ante-mortem detection of LATE. Development of a disease biomarker would augment observational studies seeking to further define the risk factors, natural history, and clinical features of LATE, as well as eventual subject recruitment for targeted therapies in clinical trials

Frequency of LATE neuropathologic change across the spectrum of Alzheimer’s disease neuropathology: combined data from 13 community-based or population-based autopsy cohorts

Limbic-predominant age-related TDP-43 encephalopathy neuropathologic change (LATE-NC) and Alzheimer’s disease neuropathologic change (ADNC) are each associated with substantial cognitive impairment in aging populations. However, the prevalence of LATE-NC across the full range of ADNC remains uncertain. To address this knowledge gap, neuropathologic, genetic, and clinical data were compiled from 13 high-quality community- and population-based longitudinal studies. Participants were recruited from United States (8 cohorts, including one focusing on Japanese–American men), United Kingdom (2 cohorts), Brazil, Austria, and Finland. The total number of participants included was 6196, and the average age of death was 88.1 years. Not all data were available on each individual and there were differences between the cohorts in study designs and the amount of missing data. Among those with known cognitive status before death (n = 5665), 43.0% were cognitively normal, 14.9% had MCI, and 42.4% had dementia—broadly consistent with epidemiologic data in this age group. Approximately 99% of participants (n = 6125) had available CERAD neuritic amyloid plaque score data. In this subsample, 39.4% had autopsy-confirmed LATE-NC of any stage. Among brains with “frequent” neuritic amyloid plaques, 54.9% had comorbid LATE-NC, whereas in brains with no detected neuritic amyloid plaques, 27.0% had LATE-NC. Data on LATE-NC stages were available for 3803 participants, of which 25% had LATE-NC stage > 1 (associated with cognitive impairment). In the subset of individuals with Thal Aβ phase = 0 (lacking detectable Aβ plaques), the brains with LATE-NC had relatively more severe primary age-related tauopathy (PART). A total of 3267 participants had available clinical data relevant to frontotemporal dementia (FTD), and none were given the clinical diagnosis of definite FTD nor the pathological diagnosis of frontotemporal lobar degeneration with TDP-43 inclusions (FTLD-TDP). In the 10 cohorts with detailed neurocognitive assessments proximal to death, cognition tended to be worse with LATE-NC across the full spectrum of ADNC severity. This study provided a credible estimate of the current prevalence of LATE-NC in advanced age. LATE-NC was seen in almost 40% of participants and often, but not always, coexisted with Alzheimer’s disease neuropathology

Effects of Blended (Yellow) vs Forced Coagulation (Blue) Currents on Adverse Events, Complete Resection, or Polyp Recurrence After Polypectomy in a Large Randomized Trial

Background & aims: There is debate over the type of electrosurgical setting that should be used for polyp resection. Some endoscopists use a type of blended current (yellow), whereas others prefer coagulation (blue). We performed a single-blinded, randomized trial to determine whether type of electrosurgical setting affects risk of adverse events or recurrence. Methods: Patients undergoing endoscopic mucosal resection of nonpedunculated colorectal polyps 20 mm or larger (n = 928) were randomly assigned, in a 2 × 2 design, to groups that received clip closure or no clip closure of the resection defect (primary intervention) and then to either a blended current (Endocut Q) or coagulation current (forced coagulation) (Erbe Inc) (secondary intervention and focus of the study). The study was performed at multiple centers, from April 2013 through October 2017. Patients were evaluated 30 days after the procedure (n = 919), and 675 patients underwent a surveillance colonoscopy at a median of 6 months after the procedure. The primary outcome was any severe adverse event in a per patient analysis. Secondary outcomes were complete resection and recurrence at first surveillance colonoscopy in a per polyp analysis. Results: Serious adverse events occurred in 7.2% of patients in the Endocut group and 7.9% of patients in the forced coagulation group, with no significant differences in the occurrence of types of events. There were no significant differences between groups in proportions of polyps that were completely removed (96% in the Endocut group vs 95% in the forced coagulation group) or the proportion of polyps found to have recurred at surveillance colonoscopy (17% and 17%, respectively). Procedural characteristics were comparable, except that 17% of patients in the Endocut group had immediate bleeding that required an intervention, compared with 11% in the forced coagulation group (P = .006). Conclusions: In a randomized trial to compare 2 commonly used electrosurgical settings for the resection of large colorectal polyps (Endocut vs forced coagulation), we found no difference in risk of serious adverse events, complete resection rate, or polyp recurrence. Electrosurgical settings can therefore be selected based on endoscopist expertise and preference

Clip Closure Prevents Bleeding After Endoscopic Resection of Large Colon Polyps in a Randomized Trial

Background & aims: Bleeding is the most common severe complication after endoscopic mucosal resection of large colon polyps and is associated with significant morbidity and cost. We examined whether prophylactic closure of the mucosal defect with hemoclips after polyp resection reduces the risk of bleeding. Methods: We performed a multicenter, randomized trial of patients with a large nonpedunculated colon polyp (≥20 mm) at 18 medical centers in North America and Spain from April 2013 through October 2017. Patients were randomly assigned to groups that underwent endoscopic closure with a clip (clip group) or no closure (control group) and followed. The primary outcome, postprocedure bleeding, was defined as a severe bleeding event that required hospitalization, a blood transfusion, colonoscopy, surgery, or another invasive intervention within 30 days after completion of the colonoscopy. Subgroup analyses included postprocedure bleeding with polyp location, polyp size, or use of periprocedural antithrombotic medications. We also examined the risk of any serious adverse event. Results: A total of 919 patients were randomly assigned to groups and completed follow-up. Postprocedure bleeding occurred in 3.5% of patients in the clip group and 7.1% in the control group (absolute risk difference [ARD] 3.6%; 95% confidence interval [CI] 0.7%-6.5%). Among 615 patients (66.9%) with a proximal large polyp, the risk of bleeding in the clip group was 3.3% and in the control group was 9.6% (ARD 6.3%; 95% CI 2.5%-10.1%); among patients with a distal large polyp, the risks were 4.0% in the clip group and 1.4% in the control group (ARD -2.6%; 95% CI -6.3% to -1.1%). The effect of clip closure was independent of antithrombotic medications or polyp size. Serious adverse events occurred in 4.8% of patients in the clip group and 9.5% of patients in the control group (ARD 4.6%; 95% CI 1.3%-8.0%). Conclusions: In a randomized trial, we found that endoscopic clip closure of the mucosal defect following resection of large colon polyps reduces risk of postprocedure bleeding. The protective effect appeared to be restricted to large polyps located in the proximal colon