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Sleep contributes to memory retention and recall. Alzheimer’s disease (AD) patients experience decreased slow wave activity (SWA) during sleep. This decrease in SWA is associated with impaired memory consolidation (Lee et al., 2020). Long-term forgetting (LTF) over days or weeks has been linked to memory consolidation deficits and has been suggested as an early marker of AD that could be useful for identifying at-risk individuals for preclinical AD trials (Weston et al., 2018). Here, we examined associations between LTF and SWA in a sample of Presenilin-1 (PSEN1) E280A mutation carriers with autosomal dominant Alzheimer’s disease and non-carrier family members. Carriers of this mutation usually develop dementia in their forties (Fuller et al., 2019).
Participants and Methods:
Fourteen cognitively unimpaired PSEN1-E280A mutation carriers and sixteen age-matched non-carriers (mean age: 34.2 years) from the Colombia-Boston (COLBOS) biomarker study were included. Participants completed an overnight polysomnogram (PSG) and memory testing (NEUROPSI Word List) at 3-time points: 1) the night before PSG: immediate recall (Day1-ImmRecall) and a 20-minute delayed recall (Day1-DelayedRecall), 2) recall the following day (Day2-recall), and 3) recall one week later (Day7-recall). SWA was measured as the ratio 0. 6-1Hz/0.6-4Hz in frontopolar and frontotemporal regions and was calculated for sleep stages N2+N3 (slow wave sleep) based on an automated staging algorithm. Each participant’s LTF was calculated as the percent retention between Day 1 immediate recall and Day 7 recall (Butler, 2009). Mann-Whitney U tests were used to compare differences in recall, SWA, and LTF between groups. Spearman’s correlation was used to examine the associations between memory recall at different time points and SWA, as well as between LTF and SWA.
Results:
On Day 1, carriers had lower performance in immediate recall (p=0.02), compared to non-carriers, but there were no group differences in the 20-minute delayed recall. Carriers also recalled fewer words on Day 2 (p=0.03) and Day 7 (p=0.009) and had greater LTF (p=0.03). There were no group differences in SWA. In our overall sample, worse performance on word list delayed recall on Day 1, Day 2, and Day 7 was associated with less SWA across both frontotemporal (Day1: p=0.04, Day2: p=0.02, Day7: p=0.02) and frontopolar (all Ps<0.01) regions. In carriers, only worse performance on Day 1 delayed recall was associated with lower SWA in the frontopolar region (r= 0.535; p=0.049). Memory recall on other days was not associated with SWA in any brain regions. Additionally, greater LTF was associated with less SWA across both frontopolar (r= 0.507; p=0.005) and frontotemporal regions (r= 0.463 p= 0.01).
Conclusions:
Preliminary findings suggest that long-term forgetting is associated with less slow- wave activity in preclinical autosomal dominant Alzheimer’s disease. These results also suggest that SWA may be related to pre-sleep learning and subsequent overnight memory consolidation processes. LTF testing may be useful in selecting individuals for preclinical AD trials. Future research on the impact of slow wave activity on LTF may be useful in identifying ways to enhance short- and long-term memory consolidation in individuals at greater risk for dementia.
Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen in neonatal intensive care units (NICU) that confers significant morbidity and mortality.
Objective:
Improving our understanding of MRSA transmission dynamics, especially among high-risk patients, is an infection prevention priority.
Methods:
We investigated a cluster of clinical MRSA cases in the NICU using a combination of epidemiologic review and whole-genome sequencing (WGS) of isolates from clinical and surveillance cultures obtained from patients and healthcare personnel (HCP).
Results:
Phylogenetic analysis identified 2 genetically distinct phylogenetic clades and revealed multiple silent-transmission events between HCP and infants. The predominant outbreak strain harbored multiple virulence factors. Epidemiologic investigation and genomic analysis identified a HCP colonized with the dominant MRSA outbreak strain who cared for most NICU patients who were infected or colonized with the same strain, including 1 NICU patient with severe infection 7 months before the described outbreak. These results guided implementation of infection prevention interventions that prevented further transmission events.
Conclusions:
Silent transmission of MRSA between HCP and NICU patients likely contributed to a NICU outbreak involving a virulent MRSA strain. WGS enabled data-driven decision making to inform implementation of infection control policies that mitigated the outbreak. Prospective WGS coupled with epidemiologic analysis can be used to detect transmission events and prompt early implementation of control strategies.
Congenital transmission of Chagas disease plays an important role in endemic countries because it is not a diagnosis that is encountered frequently in prenatal care. Due to limited information regarding congenital transmission of Trypanosoma cruzi in Mexico, the present study aimed to investigate protozoan infectivity and modulation of immune responses in human placental explants infected with T. cruzi Ia Mexican strains. The Inc-5 strain showed increased infectivity and modulated IL-1β, IL-10 and TLR-4, decreasing their expression after 24 h of infection. Both strains (Inc-5 and Ninoa) stimulated the production of TNF-α and decreased IL-6 levels 96 h after infection. An important detachment of the syncytiotrophoblast caused by infection with T. cruzi was observed after 24 h of infection. In this study, ex vivo infection of human placental villi was performed to better understand interactions involving parasitic T. cruzi and human placental tissue. It was concluded that the strains of TcIa present parasitism in placental tissue, modulation of the innate immune system of the placenta, and cause intense detachment of the syncytiotrophoblast, a fact that may be more associated with abortion and premature birth events than the congenital transmission itself, justifying the low rate of this transmission mechanism by this genotype.
The purpose of this article is to describe the process of developing and implementing a transdisciplinary community-based research center, the Center for Health Equity Research (CHER) Chicago, to offer a model for designing and implementing research centers that aim to address structural causes of health inequality.
Methods:
Scholars from diverse backgrounds and disciplines formed a multidisciplinary team for the Center and adopted the structural violence framework as the organizing conceptual model. All Center activities were based on community partnership. The Center activities were organized within three cores: administrative, investigator development, and community engagement and dissemination cores. The key activities during the first year were to develop a pilot grant program for early-stage investigators (ESIs) and to establish community partnership mechanisms.
Results:
CHER provided more than 60 consultations for ESIs, which resulted in 31 pilot applications over the three application cycles. Over 200 academic and community partners attended the community symposium and discussed community priority. Some challenges encountered were to improve communication among investigators, to clarify roles and responsibilities of the three cores, and to build consensus on the definition and operationalization of the concept of structural violence.
Conclusion:
There is an increasing need for local hubs to facilitate transdisciplinary collaboration and community engagement to effectively address health inequity. Building consensus around a shared vision among partners is a difficult and yet important step toward achieving equity.
The aim of the current study was to examine the heterogeneity of functional outcomes in first episode psychosis (FEP) patients and related clinical, neurocognitive and sociodemographic factors using a cluster analytic approach.
Method
A large sample of FEP patients (N = 209) was functionally reassessed 10 years after the first contact with an early intervention service. Multiple baseline, 3-year and 10-year follow-up variables were explored.
Results
The cluster analysis emphasized the existence of six independent clusters of functioning: one cluster was normal overall (42.16%), two clusters showed moderate interpersonal (9.63%) or instrumental (12.65%) deficits, two clusters showed more severe interpersonal (12.05%) or interpersonal and instrumental (13.85%) deficits and there was a significantly overall impaired cluster (9.63%). Cluster comparisons showed that several baseline and follow-up factors were differentially involved in functional outcomes.
Conclusions
The current study demonstrated that distinct clusters of functioning in FEP patients can be identified. The fact that a variety of profiles was observed contributes to a better understanding of the nature of the heterogeneity characterizing FEP patients and has clinical implications for developing individualized treatment plans.
In this contribution we describe and illustrate 14 coral morphospecies collected from the early Miocene Siamaná (Aquitanian–Burdigalian) and Jimol (late Burdigalian) formations of the Cocinetas Basin in La Guajira Peninsula, northern Colombia. Eleven were identified as already established species including seven genera belonging to the families Mussidae, Pocilloporidae, Poritidae, Siderastreidae, and Milleporidae; the other three remain in open nomenclature. Nine of the 11 species identified (81%) are extinct. The remaining two living species, Siderastrea siderea and Millepora alcicornis, are common on modern Caribbean reefs. Their presence in the Siamaná Formation extends their temporal range in the Caribbean region to the early Miocene. Most of the taxa described here were hermatypic and zooxanthellate corals of the order Scleractinia, with the exception of the fire coral Millepora alcicornis, of the order Anthothecata, family Milleporidae. The coral fauna recorded in the Siamaná and Jimol formations is typical of shallow and calm waters of the Oligocene–Miocene transition.
We document for the first time Miocene corals from the Siamaná and Jimol formations of the Cocinetas Basin in La Guajira Peninsula, northern Colombia. This is the first of two contributions dedicated to the description and detailed illustration of morphospecies collected during two scientific expeditions (2011, 2014) to the remote region. Here we report coral morphospecies attributed to the families Acroporidae, Agathiphylliidae, Astrocoeniidae, Caryophylliidae, Diploastraeidae, Merulinidae, and Montastraeidae. Eighteen species belonging to these seven families, included in nine genera, are described. Fifteen species are assigned to established taxa, while three remain in open nomenclature. Of the species identified, only Montastraea cavernosa (Linnaeus, 1767) exists today. The coral taxa described are typical of the Oligocene–Miocene transition and were important components of shallow-water reefs in the Caribbean and Gulf of Mexico region during this period. The occurrence of Agathiphyllia spp., Antiguastrea, and Diploastrea spp. confirms the presence of these genera in the Miocene of the Southern Caribbean. Coral assemblages suggest that the La Guajira coral community thrived in calm and shallow waters.
Chagas disease is a complex tropical pathology caused by the kinetoplastid Trypanosoma cruzi. This parasite displays massive genetic diversity and has been classified by international consensus in at least six Discrete Typing Units (DTUs) that are broadly distributed in the American continent. The main clinical manifestation of the disease is the chronic chagasic cardiomyopathy (CCC) that is lethal in the infected individuals. However, one intriguing feature is that only 30–40% of the infected individuals will develop CCC. Some authors have suggested that the immune response, host genetic factors, virulence factors and even the massive genetic heterogeneity of T. cruzi are responsible of this clinical pattern. To date, no conclusive data support the reason why a few percentages of the infected individuals will develop CCC. Therefore, we decided to conduct a systematic review analysing the host genetic factors, immune response, cytokine production, virulence factors and the plausible association of the parasite DTUs and CCC. The epidemiological and clinical implications are herein discussed.
CHD is becoming an increasing priority worldwide, as it is one of the main causes of death in low- and middle-income countries lately. This study aims to evaluate the association between beverage consumption patterns and the risk of CHD among Mexican adult population. We performed a cross-sectional analysis using data from 6640 adults participating in the Health Workers’ Cohort Study. Factor analysis was performed to identify beverage patterns using sex-specific Framingham prediction algorithms to estimate CHD risk. The prevalence of moderate to high CHD risk was 17·8 %. We identified four major beverage consumption patterns, which were categorised as alcohol, coffee/tea, soft drinks and low-fat milk. We observed a lower risk of CHD (OR=0·61; 95 % CI 0·46, 0·80; and OR=0·58; 95 % CI 0·43, 0·79, respectively) among participants in the upper quintile of alcohol or low-fat milk consumption compared with those in the bottom quintile. In contrast, a higher consumption of soft drinks was positively associated with CHD risk (OR=1·64; 95 % CI 1·21, 2·20) when compared with other extreme quintiles. Finally, coffee/tea consumption was not significantly associated with CHD risk. Our findings suggest that a beverage pattern characterised by a higher intake of sugar-sweetened beverages may be associated with an increased risk of CHD among the Mexican adult population, whereas patterns of moderate alcohol intake and low-fat milk may be associated with a reduced risk.
Although dendrochronological methods have the potential to provide precise calendar dates, they are virtually absent in Mesoamerican archaeological research. This absence is due to several long-standing, but erroneous, assumptions: that tree rings in this region do not reflect annual growth and environmental variability, that an adequate number of samples do not exist, and that tree-ring measurements cannot be useful without modern trees to link prehispanic chronologies. In this article we present data from the sites of La Quemada and Los Pilarillos, located in the Malpaso Valley, Zacatecas, to demonstrate that suitable archaeologically derived samples of dendrochronologically useful species do exist, that the samples from these sites are measurable and cross-datable, and that the tree rings can yield precise calendar dates using a method that “wiggle-matches” radiocarbon dates on tree-ring sequences. The work demonstrates the potential of these methods to address chronological, and, in the future, climatic questions, which have so far eluded archaeological work in the region.
To prospectively examine the extent to which mealtime habits influences the risk of weight gain and obesity in Mexican adults.
Design
We performed a prospective cohort study. The Mealtime Habits Quality (MHQ) scale was used for assessing participants’ MHQ; the outcomes of interest were gain ≥5 % of body weight, developing overweight/obesity and abdominal obesity, after 7 years of follow-up. In order to estimate the independent effect of MHQ on anthropometric indicators, generalized linear models were computed to obtain adjusted relative risks (95 % CI).
Setting
The state of Morelos, Mexico.
Subjects
Mexican adults (n 837) aged 18–70 years participating in a cohort study.
Results
Compared with participants classified in the higher MHQ category, individuals in the middle and lower MHQ groups had a 4·1 (2·5, 6·7) and 6·2 (3·9, 9·7) fold greater risk of gain ≥5 % of body weight, respectively; 6·6 (2·8, 15·5) and 8·6 (3·7, 19·8) fold greater risk of becoming overweight/obese, respectively; and 3·8 (2·0, 7·3) and 5·3 (2·8, 9·8) fold greater risk of developing abdominal obesity, respectively.
Conclusions
This study provides evidence about the influence of a set of mealtime habits on obesity indicators, showing that greater adherence to unadvisable mealtime habits increases the risk of developing unhealthy anthropometric indicators. Since the meal is one of the most important sources of food intake, and consequently weight status, the MHQ scale can be a useful population tool to predict weight gain and obesity.
The present study aimed to evaluate the nutritional status of pregnant women in Colombia and the associations between gestational BMI and sociodemographic and gestational characteristics.
Design
Cross-sectional study. A secondary analysis was made of data from the 2005 Demographic and Health Survey of Colombia.
Setting
Bogotá, Colombia.
Subjects
Pregnant adolescents aged 13–19 years (n 430) and pregnant women aged 20–49 years (n 1272).
Results
The gestational BMI and sociodemographic characteristics of the adolescents differed from those of the pregnant adult women. Thirty-one per cent of the adolescents were underweight for gestational age, compared with 14·5 % of the adult women. Eighteen per cent of adolescents were overweight for gestational age, in contrast to 37·3 % of adult women. The overall prevalence of anaemia was 44·7 % and the prevalence of low serum ferritin was 38·8 %. Women within the high quintiles of the wealth index (prevalence odds ratio (POR) = 0·56; 95 % CI 0·34, 0·91, P < 0·02) had lower odds of being underweight. Women who received prenatal care (POR = 2·17; 95 % CI 1·48, 3·09, P < 0·001) and were multiparous (POR = 2·10; 95 % CI 1·43, 3·15, P < 0·0 0 1) had higher odds of being overweight. Women in extended families (POR = 0·63; 95 % CI 0·50, 0·95, P < 0·025) had lower odds of being overweight.
Conclusions
Underweight in pregnant adolescents and overweight in adult women coexist as a double burden in Colombia. Factors associated with malnutrition among pregnant women and adolescents should be considered for future interventions in countries experiencing nutritional transition.