TREM2 drives microglia response to amyloid-ß via SYK-dependent and -independent pathways.

Genetic studies have highlighted microglia as pivotal in orchestrating Alzheimer's disease (AD). Microglia that adhere to Aß plaques acquire a transcriptional signature, "disease-associated microglia" (DAM), which largely emanates from the TREM2-DAP12 receptor complex that transmits intracellular signals through the protein tyrosine kinase SYK. The human TREM2R47H variant associated with high AD risk fails to activate microglia via SYK. We found that SYK-deficient microglia cannot encase Aß plaques, accelerating brain pathology and behavioral deficits. SYK deficiency impaired the PI3K-AKT-GSK-3ß-mTOR pathway, incapacitating anabolic support required for attaining the DAM profile. However, SYK-deficient microglia proliferated and advanced to an Apoe-expressing prodromal stage of DAM; this pathway relied on the adapter DAP10, which also binds TREM2. Thus, microglial responses to Aß involve non-redundant SYK- and DAP10-pathways. Systemic administration of an antibody against CLEC7A, a receptor that directly activates SYK, rescued microglia activation in mice expressing the TREM2R47H allele, unveiling new options for AD immunotherapy.

A Cre-deleter specific for embryo-derived brain macrophages reveals distinct features of microglia and border macrophages.

Genetic tools to target microglia specifically and efficiently from the early stages of embryonic development are lacking. We generated a constitutive Cre line controlled by the microglia signature gene Crybb1 that produced nearly complete recombination in embryonic brain macrophages (microglia and border-associated macrophages [BAMs]) by the perinatal period, with limited recombination in peripheral myeloid cells. Using this tool in combination with Flt3-Cre lineage tracer, single-cell RNA-sequencing analysis, and confocal imaging, we resolved embryonic-derived versus monocyte-derived BAMs in the mouse cortex. Deletion of the transcription factor SMAD4 in microglia and embryonic-derived BAMs using Crybb1-Cre caused a developmental arrest of microglia, which instead acquired a BAM specification signature. By contrast, the development of genuine BAMs remained unaffected. Our results reveal that SMAD4 drives a transcriptional and epigenetic program that is indispensable for the commitment of brain macrophages to the microglia fate and highlight Crybb1-Cre as a tool for targeting embryonic brain macrophages.

A distinct human cell type expressing MHCII and RORγt with dual characteristics of dendritic cells and type 3 innate lymphoid cells.

Recent studies have characterized various mouse antigen-presenting cells (APCs) expressing the lymphoid-lineage transcription factor RORγt (Retinoid-related orphan receptor gamma t), which exhibit distinct phenotypic features and are implicated in the induction of peripheral regulatory T cells (Tregs) and immune tolerance to microbiota and self-antigens. These APCs encompass Janus cells and Thetis cell subsets, some of which express the AutoImmune REgulator (AIRE). RORγt+ MHCII+ type 3 innate lymphoid cells (ILC3) have also been implicated in the instruction of microbiota-specific Tregs. While RORγt+ APCs have been actively investigated in mice, the identity and function of these cell subsets in humans remain elusive. Herein, we identify a rare subset of RORγt+ cells with dendritic cell (DC) features through integrated single-cell RNA sequencing and single-cell ATAC sequencing. These cells, which we term RORγt+ DC-like cells (R-DC-like), exhibit DC morphology, express the MHC class II machinery, and are distinct from all previously reported DC and ILC3 subsets, but share transcriptional and epigenetic similarities with DC2 and ILC3. We have developed procedures to isolate and expand them in vitro, enabling their functional characterization. R-DC-like cells proliferate in vitro, continue to express RORγt, and differentiate into CD1c+ DC2-like cells. They stimulate the proliferation of allogeneic T cells. The identification of human R-DC-like cells with proliferative potential and plasticity toward CD1c+ DC2-like cells will prompt further investigation into their impact on immune homeostasis, inflammation, and autoimmunity.

Mucosal Single-Cell Profiling of Crohn's-Like Disease of the Pouch Reveals Unique Pathogenesis and Therapeutic Targets.

BACKGROUND & AIMS: The pathophysiology of Crohn's-like disease of the pouch (CDP) in patients with a history of ulcerative colitis (UC) is unknown. We examined mucosal cells from patients with and without CDP using single-cell analyses. METHODS: Endoscopic samples were collected from pouch body and prepouch ileum (pouch/ileum) of 50 patients with an ileal pouch-anal anastomosis. Single-cell RNA sequencing was performed on pouch/ileal tissues of patients with normal pouch/ileum and CDP. Mass cytometry was performed on mucosal immune cells from patients with UC with normal pouch/ileum, CDP, pouchitis, and those with familial adenomatous polyposis after pouch formation. Findings were independently validated using immunohistochemistry. RESULTS: The cell populations/states in the pouch body differed from those in the prepouch ileum, likely secondary to increased microbial burden. Compared with the familial adenomatous polyposis pouch, the UC pouch was enriched in colitogenic immune cells even without inflammation. CDP was characterized by increases in T helper 17 cells, inflammatory fibroblasts, inflammatory monocytes, TREM1+ monocytes, clonal expansion of effector T cells, and overexpression of T helper 17 cells-inducing cytokine genes such as IL23, IL1B, and IL6 by mononuclear phagocytes. Ligand-receptor analysis further revealed a stromal-mononuclear phagocytes-lymphocyte circuit in CDP. Integrated analysis showed that up-regulated immune mediators in CDP were similar to those in CD and pouchitis, but not UC. Additionally, CDP pouch/ileum exhibited heightened endoplasmic reticulum stress across all major cell compartments. CONCLUSIONS: CDP likely represents a distinct entity of inflammatory bowel disease with heightened endoplasmic reticulum stress in both immune and nonimmune cells, which may become a novel diagnostic biomarker and therapeutic target for CDP.

Asian Cohort for Alzheimer Disease (ACAD) Pilot Study: Vietnamese Americans.

INTRODUCTION: The objective of this pilot study was to establish the feasibility of recruiting older Vietnamese Americans for research addressing genetic and nongenetic risk factors for Alzheimer disease (AD). METHODS: Twenty-six Vietnamese Americans were recruited from communities in San Diego. A Community Advisory Board provided cultural and linguistic advice. Bilingual/bicultural staff measured neuropsychological, neuropsychiatric, lifestyle, and medical/neurological functioning remotely. Saliva samples allowed DNA extraction. A consensus team reviewed clinical data to determine a diagnosis of normal control (NC), mild cognitive impairment (MCI), or dementia. Exploratory analyses addressed AD risk by measuring subjective cognitive complaints (SCC), depression, and vascular risk factors (VRFs). RESULTS: Twenty-five participants completed the study (mean age=73.8 y). Eighty percent chose to communicate in Vietnamese. Referrals came primarily from word of mouth within Vietnamese communities. Diagnoses included 18 NC, 3 MCI, and 4 dementia. Participants reporting SCC acknowledged more depressive symptoms and had greater objective cognitive difficulty than those without SCC. Eighty-eight percent of participants reported at least 1 VRF. DISCUSSION: This pilot study supports the feasibility of conducting community-based research in older Vietnamese Americans. Challenges included developing linguistically and culturally appropriate cognitive and neuropsychiatric assessment tools. Exploratory analyses addressing nongenetic AD risk factors suggest topics for future study.

Asian Cohort for Alzheimer's Disease (ACAD) pilot study on genetic and non-genetic risk factors for Alzheimer's disease among Asian Americans and Canadians.

INTRODUCTION: Clinical research in Alzheimer's disease (AD) lacks cohort diversity despite being a global health crisis. The Asian Cohort for Alzheimer's Disease (ACAD) was formed to address underrepresentation of Asians in research, and limited understanding of how genetics and non-genetic/lifestyle factors impact this multi-ethnic population. METHODS: The ACAD started fully recruiting in October 2021 with one central coordination site, eight recruitment sites, and two analysis sites. We developed a comprehensive study protocol for outreach and recruitment, an extensive data collection packet, and a centralized data management system, in English, Chinese, Korean, and Vietnamese. RESULTS: ACAD has recruited 606 participants with an additional 900 expressing interest in enrollment since program inception. DISCUSSION: ACAD's traction indicates the feasibility of recruiting Asians for clinical research to enhance understanding of AD risk factors. ACAD will recruit > 5000 participants to identify genetic and non-genetic/lifestyle AD risk factors, establish blood biomarker levels for AD diagnosis, and facilitate clinical trial readiness. HIGHLIGHTS: The Asian Cohort for Alzheimer's Disease (ACAD) promotes awareness of under-investment in clinical research for Asians. We are recruiting Asian Americans and Canadians for novel insights into Alzheimer's disease. We describe culturally appropriate recruitment strategies and data collection protocol. ACAD addresses challenges of recruitment from heterogeneous Asian subcommunities. We aim to implement a successful recruitment program that enrolls across three Asian subcommunities.

Preventing the COVID-19 Outbreak in Vietnam: Social Media Campaign Exposure and the Role of Interpersonal Communication.

The present study focused on the success story of Vietnam's ability to control the COVID-19 outbreak in the early stages to examine the associations between exposure to the Vietnam Ministry of Health's COVID-19 prevention social media campaign messages, interpersonal communication, attitudes, perceived norms, self-efficacy, and intentions to stay at home. A cross-sectional survey was conducted with residents in Ho Chi Minh City (N = 360). Results from mediation analyses indicated that interpersonal communication mediated the effect of social media campaign exposure on intentions to stay at home. Moreover, interpersonal communication shaped injunctive norms and self-efficacy that were conducive to behavioral intentions. These results underscored the need to leverage the power of social media and interpersonal communication in public health campaigns to prevent infectious outbreaks.

Before Omicron's Arrival: Effects of Negative Emotions and Comparative Optimism on COVID-19 Protection and Detection Behaviors.

This study examined the associations of emotions, cognitions, and behavioral intentions in response to exposure to news stories reporting on the arrival of Omicron variant in Vietnam. Outcomes included fear, anxiety, anger, comparative optimism, intentions to conduct prevention behavior (wash hands with soap), detection behavior (test for Omicron infection), and share health information. Two experiments were conducted with participants being randomized to either low-risk or high-risk condition that contained information promoting hand-washing with soap (Experiment 1, N = 303), or information promoting COVID-19 testing (Experiment 2, N = 303). Results indicated that viewing high-risk news stories led to higher fear, anxiety, and anger than low-risk news stories. Fear fully mediated the effect of news exposure on intentions to test for Omicron infection and share health information. Comparative optimism moderated the indirect effect of news exposure on intentions to wash hands with soap and share information about COVID-19 testing. Theoretical and practical implications were discussed.

Cannabis use for Sleep Disturbance Among Older Patients in a Geriatrics Clinic.

Cannabis use is growing among older adults to manage medical concerns including poor sleep. In this study, we characterized how patients seen at a geriatrics clinic use cannabis to address sleep disturbance. Specifically, we conducted an anonymous survey of 568 adults, including 83 who reported cannabis use within the past 3 years, to inquire about such use. We compared cannabis use characteristics between those using it for sleep disturbance versus all other conditions. We considered a p-value <.10 to be statistically significant. Among the cannabis users in our sample, 29% reported using cannabis for sleep disturbance (N = 24). They were more likely than other users to be female (p = .07), consume cannabis more frequently (p = .01), use products containing tetrahydrocannabinol (THC) (vs. cannabidiol [CBD]-only; p < .01), and use cannabis to target more symptoms (p < .01). As cannabis use continues to grow in older populations, it is essential to delineate better how cannabis may be used safely and effectively to improve older adults' sleep health.

Uncoupling gene expression noise along the central dogma using genome engineered human cell lines.

Eukaryotic protein synthesis is an inherently stochastic process. This stochasticity stems not only from variations in cell content between cells but also from thermodynamic fluctuations in a single cell. Ultimately, these inherently stochastic processes manifest as noise in gene expression, where even genetically identical cells in the same environment exhibit variation in their protein abundances. In order to elucidate the underlying sources that contribute to gene expression noise, we quantify the contribution of each step within the process of protein synthesis along the central dogma. We uncouple gene expression at the transcriptional, translational, and post-translational level using custom engineered circuits stably integrated in human cells using CRISPR. We provide a generalized framework to approximate intrinsic and extrinsic noise in a population of cells expressing an unbalanced two-reporter system. Our decomposition shows that the majority of intrinsic fluctuations stem from transcription and that coupling the two genes along the central dogma forces the fluctuations to propagate and accumulate along the same path, resulting in increased observed global correlation between the products.

Targeting the E3 ubiquitin ligases DCAF15 and cereblon for cancer therapy.

Small molecule-mediated inhibition of protein function is the rational behind therapeutic efficacy of the majority clinically used drugs. In order for a drug to achieve pharmacologically relevant inhibition, efficient target engagement at high selectivity and specificity is necessary to obtain the desired therapeutic effect minimizing offtarget outcomes. Majority of small molecules approaches developed so far have failed in their attempt to reach clinical efficacy because of low selectivity and low specificity in achieving close to 100 % target inhibition. Recently, approaches that directly control cellular protein levels have opened the potential to accomplish a high grade of efficacy not imaginable with traditional small-molecule inhibitors. Research in this area has just started opening avenues to effectively degrade a cellular target of choice and will soon impact clinical efficacy.

The Biology of F-box Proteins: The SCF Family of E3 Ubiquitin Ligases.

F-box proteins function as substrate adaptors for the S-phase kinase-associated protein 1 (SKP1)-cullin 1 (CUL1)-F-box protein (SCF) ubiquitin ligase complexes, which mediate the proteasomal degradation of a diverse range of regulatory proteins. 20 years since the F-box protein family has been discovered, our understanding of substrate-recognition regulation and the roles F-box proteins play in cellular processes has continued to expand. Here, we provide an introduction to the discovery and classification of F-box proteins, the overall structural assembly of SCF complexes, the varied mechanisms by which F-box proteins recognize their substrates, and the role F-box proteins play in diseases and their potentials in targeted therapies.

Ensemble simulations: folding, unfolding and misfolding of a high-efficiency frameshifting RNA pseudoknot.

Massive all-atom molecular dynamics simulations were conducted across a distributed computing network to study the folding, unfolding, misfolding and conformational plasticity of the high-efficiency frameshifting double mutant of the 26 nt potato leaf roll virus RNA pseudoknot. Our robust sampling, which included over 40 starting structures spanning the spectrum from the extended unfolded state to the native fold, yielded nearly 120 µs of cumulative sampling time. Conformational microstate transitions on the 1.0 ns to 10.0 µs timescales were observed, with post-equilibration sampling providing detailed representations of the conformational free energy landscape and the complex folding mechanism inherent to the pseudoknot motif. Herein, we identify and characterize two alternative native structures, three intermediate states, and numerous misfolded states, the latter of which have not previously been characterized via atomistic simulation techniques. While in line with previous thermodynamics-based models of a general RNA folding mechanism, our observations indicate that stem-strand-sequence-separation may serve as an alternative predictor of the order of stem formation during pseudoknot folding. Our results contradict a model of frameshifting based on structural rigidity and resistance to mechanical unfolding, and instead strongly support more recent studies in which conformational plasticity is identified as a determining factor in frameshifting efficiency.

Effect of polyDADMAC on aggregation of clay-size particles in red mud: Implications for immobilization practices.

PolyDADMAC (PD) is a high charge density cationic polymer of diallyldimethylammonium chloride which has been recently developed as a coagulant in water purification. As PD has high affinity to fine negatively-charged colloids, it is worth to ascertain if PD can affect surface properties of clay-size particles in red mud waste and be applied to develop immobilization techniques for red mud storage areas. In the current study, a test tube method in combination with surface charge measurement was used for determination of the colloidal properties of a red mud sample under the variation of PD, soluble Al and Si, and variable pH conditions. Observations for the PD concentration range from 0.25 to 2.0 mM revealed that PD can increase surface charge and enhance aggregation or at least shift the aggregation zone to higher pH. This suggests a possible application of PD for immobilization of red mud in alkaline condition. It was also found that soluble Al and Si acted to modify the effect of PD and aggregation properties of red mud. While soluble Si supported aggregation, Al appeared as an enhancer for dispersion of red mud. It implies that development of PD-based techniques for immobilization of red mud needs to consider the effects of soluble Al and Si.

Protein Nanosheet Mechanics Controls Cell Adhesion and Expansion on Low-Viscosity Liquids.

Adherent cell culture typically requires cell spreading at the surface of solid substrates to sustain the formation of stable focal adhesions and assembly of a contractile cytoskeleton. However, a few reports have demonstrated that cell culture is possible on liquid substrates such as silicone and fluorinated oils, even displaying very low viscosities (0.77 cSt). Such behavior is surprising as low viscosity liquids are thought to relax much too fast (

Examining unmet needs: a cross-sectional study exploring knowledge, attitudes and sexually transmitted infection screening preferences among persons who inject drugs in Camden, New Jersey.

OBJECTIVES: To inform the development of targeted sexually transmitted infection (STI) control programmes for persons who inject drugs (PWID). METHODS: We recruited 116 PWID (aged ≥ 18 years) from a community-based syringe exchange programme (SEP) and assessed their STI knowledge and screening preferences via technology assisted self-interview. We estimated prevalence of STI transmission knowledge, attitudes and screening preferences as well as the association between reported sexual behaviours (past 6 months) and willingness to self-collect specimens. RESULTS: Participants were white (77%), female (51%) and heterosexual (77%). STI knowledge regarding transmission and testing was high among the sample. More than 70% of participants were aware extragenital infections were possible and were least likely to know urine tests do not detect rectal infections (40.9%). Site-specific specimen collection was highly reflective of reported sexual behaviour. PWID who reported receptive sex (36% vs 5%, p<0.01) and insertive anal sex (31% vs 6%, p=0.01) were more likely to collect rectal specimens than those who did not. A similar trend was seen for oral sex performance on men and self-collection of oropharyngeal swabs (15% vs 3%, p=0.04). In addition, participants preferred collecting their own sample to having a clinician collect it for them (69% vs 31%, p<0.01) and testing at the SEP compared with a STI clinic (86% vs 14%, p<0.01). CONCLUSION: Our findings suggest site-specific specimen collection may be a proxy for risk behaviour engagement in this fairly knowledgeable high-risk population. To increase case finding, STI control programmes should educate patients about site-specific screening and pair outreach with the infrastructure provided by SEPs, in settings where these programmes exist.

NPCC4: Advancing climate justice in climate adaptation strategies for New York City.

The Advancing Climate Justice in Climate Adaptation Strategies for New York City (Equity) chapter of NPCC4 builds on the findings and recommendations from NPCC3 to identify additional metrics and adaptation efforts that can advance climate justice. First, the chapter assesses the efforts of the City to incorporate equity into climate adaptation efforts since NPCC3 and describes how the communities profiled in NPCC3 have implemented and evolved their approaches to addressing the intersecting climate, environmental, and social stressors that they continue to face. Second, it adds to the historical context of climate inequity by linking the bioregion's history of colonization, land dispossession, and slavery building on emerging evidence demonstrating how historical and contemporary land use patterns and decisions shape present and future climate risks and social vulnerability, including climate displacement. Third, it recommends a NYC-focused metric to identify areas of the city that are most vulnerable to the intersection of climate hazards, social vulnerability, and displacement. Finally, it highlights approaches to more equitable and just climate adaptation drawn from local, national, and international examples. As such, the chapter offers best practices that prioritize community-driven climate resilience approaches that are integrated, more equitable, and racially just.

Genome-wide association study for age-related hearing loss in CFW mice.

Age-related hearing impairment is the most common cause of hearing loss and is one of the most prevalent conditions affecting the elderly globally. It is influenced by a combination of environmental and genetic factors. The mouse and human inner ears are functionally and genetically homologous. Investigating the genetic basis of age-related hearing loss (ARHL) in an outbred mouse model may lead to a better understanding of the molecular mechanisms of this condition. We used Carworth Farms White (CFW) outbred mice, because they are genetically diverse and exhibit variation in the onset and severity of ARHL. The goal of this study was to identify genetic loci involved in regulating ARHL. Hearing at a range of frequencies was measured using Auditory Brainstem Response (ABR) thresholds in 946 male and female CFW mice at the age of 1, 6, and 10 months. We obtained genotypes at 4.18 million single nucleotide polymorphisms (SNP) using low-coverage (mean coverage 0.27x) whole-genome sequencing followed by imputation using STITCH. To determine the accuracy of the genotypes we sequenced 8 samples at >30x coverage and used calls from those samples to estimate the discordance rate, which was 0.45%. We performed genetic analysis for the ABR thresholds for each frequency at each age, and for the time of onset of deafness for each frequency. The SNP heritability ranged from 0 to 42% for different traits. Genome-wide association analysis identified several regions associated with ARHL that contained potential candidate genes, including Dnah11, Rapgef5, Cpne4, Prkag2, and Nek11. We confirmed, using functional study, that Prkag2 deficiency causes age-related hearing loss at high frequency in mice; this makes Prkag2 a candidate gene for further studies. This work helps to identify genetic risk factors for ARHL and to define novel therapeutic targets for the treatment and prevention of ARHL.

The relationship between population growth and precipitation change in some regions across Vietnam: implications for urbanization effect.

According to a review of numerous publications and scientific reports, the effects of urbanization on urban climate are of greatest concern. This study aims to evaluate the impact of urbanization focusing on population growth on precipitation trends in 11 provinces across Vietnam during the period 2008-2018 by identifying the relationship between population growth and precipitation change. Regression analysis is used to determine the trends of precipitation and population growth. Precipitation maps and graphs show the overall precipitation trends, changes, and patterns in past decades. Overall, population growth tends to correlate with precipitation change trends. Furthermore, the type of region groups (countryside region, small city, or medium city) also plays a crucial role in determining the magnitude of the change in precipitation trends for each region. This further lends credibility to the notion that urbanization contributes to changes in precipitation trends.

Multifocal fatty liver nodules mimicking a metastatic disease: A case report.

Multifocal fatty liver nodules can present a diagnostic challenge due to their resemblance to metastatic liver disease. This case report illustrates the complexity of such scenarios through the presentation of a middle-aged male patient. Despite the common nature of fatty liver disease, characterized by hepatocyte fat accumulation leading to diffuse and uniform liver lesions, rare instances exhibit heterogeneous appearances. The case underlines the potential confusion arising from imaging modalities when multiple small nodules disperse throughout the liver, mimicking multifocal tumors or metastases. The report emphasizes the critical role of comprehensive diagnostic procedures in preventing misdiagnosis and unwarranted interventions. Effective management hinges on multidisciplinary collaboration among specialists, ensuring accurate differentiation and appropriate treatment. This study serves as a reminder of the intricacies involved in interpreting multifocal fatty liver nodules that may masquerade as metastatic disease, highlighting the need for precision in clinical practice.