Mammalian SWI/SNF complex activity regulates POU2F3 and constitutes a targetable dependency in small cell lung cancer.

Small cell lung cancers (SCLCs) are composed of heterogeneous subtypes marked by lineage-specific transcription factors, including ASCL1, NEUROD1, and POU2F3. POU2F3-positive SCLCs, ∼12% of all cases, are uniquely dependent on POU2F3 itself; as such, approaches to attenuate POU2F3 expression may represent new therapeutic opportunities. Here using genome-scale screens for regulators of POU2F3 expression and SCLC proliferation, we define mSWI/SNF complexes as top dependencies specific to POU2F3-positive SCLC. Notably, chemical disruption of mSWI/SNF ATPase activity attenuates proliferation of all POU2F3-positive SCLCs, while disruption of non-canonical BAF (ncBAF) via BRD9 degradation is effective in pure non-neuroendocrine POU2F3-SCLCs. mSWI/SNF targets to and maintains accessibility over gene loci central to POU2F3-mediated gene regulatory networks. Finally, clinical-grade pharmacologic disruption of SMARCA4/2 ATPases and BRD9 decreases POU2F3-SCLC tumor growth and increases survival in vivo. These results demonstrate mSWI/SNF-mediated governance of the POU2F3 oncogenic program and suggest mSWI/SNF inhibition as a therapeutic strategy for POU2F3-positive SCLCs.

Evaluation of the Early Administration of Tranexamic Acid in Geriatric Hip Fractures in the Emergency Department: A Retrospective Study.

Introduction Tranexamic acid (TXA) administration perioperatively has demonstrated efficacy in reducing postoperative drops in hemoglobin levels and the need for transfusions among patients with peritrochanteric hip fractures. This study aims to perform a retrospective analysis to assess the impact on hemoglobin levels by comparing patients with fragility hip fractures who received TXA in the ED, in addition to the standard perioperative TXA dose, with those who did not receive TXA in the ED. Methods This study retrospectively reviewed 64 patient records from May 2020 to May 2021 at a Level II trauma center that were classified into two groups: patients who received one gram (g) of TXA in the ED, within five hours of injury (new protocol), or patients who received no TXA in the ED (old protocol). The primary outcomes of the study were hemoglobin and adverse events. An independent t-test was performed on continuous variables. A chi-square test was used to analyze noncontinuous variables. Statistical Product and Service Solutions (SPSS, version 25; IBM SPSS Statistics for Windows, Armonk, NY) was used for analysis. Statistical significance was set at a p value < 0.05. Results We measured the difference between hemoglobin on the day of surgery or day zero and on arrival in the ED, which was not statistically significant between the two protocols (p value = 0.322). The difference between hemoglobin levels on postoperative day one and on arrival in the ED was also not statistically significant (p = 0.339). Adverse events were lower in the new protocol but not statistically significant between the two protocols (p = 0.178). Conclusion Our study showed improved outcomes in postoperative hemoglobin with early administration of TXA in the ED. This is demonstrated by continuous higher postoperative hemoglobin in the new protocol group without an increase in adverse events. While the data did not achieve statistical significance, we believe there is clinical benefit in the early administration of TXA in the ED, a finding that continues to be explored and supported in the literature.

Metagenomic Detection of Bacterial Zoonotic Pathogens among Febrile Patients, Tanzania, 2007-20091.

Bacterial zoonoses are established causes of severe febrile illness in East Africa. Within a fever etiology study, we applied a high-throughput 16S rRNA metagenomic assay validated for detecting bacterial zoonotic pathogens. We enrolled febrile patients admitted to 2 referral hospitals in Moshi, Tanzania, during September 2007-April 2009. Among 788 participants, median age was 20 (interquartile range 2-38) years. We performed PCR amplification of V1-V2 variable region 16S rRNA on cell pellet DNA, then metagenomic deep-sequencing and pathogenic taxonomic identification. We detected bacterial zoonotic pathogens in 10 (1.3%) samples: 3 with Rickettsia typhi, 1 R. conorii, 2 Bartonella quintana, 2 pathogenic Leptospira spp., and 1 Coxiella burnetii. One other sample had reads matching a Neoerhlichia spp. previously identified in a patient from South Africa. Our findings indicate that targeted 16S metagenomics can identify bacterial zoonotic pathogens causing severe febrile illness in humans, including potential novel agents.

Depletion of TDP-43 exacerbates tauopathy-dependent brain atrophy by sensitizing vulnerable neurons to caspase 3-mediated endoproteolysis of tau in a mouse model of Multiple Etiology Dementia.

TDP-43 proteinopathy, initially disclosed in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), coexists with tauopathy in a variety of neurodegenerative disorders, termed multiple etiology dementias (MEDs), including Alzheimer's Disease (AD). While such co-pathology of TDP-43 is strongly associated with worsened neurodegeneration and steeper cognitive decline, the pathogenic mechanism underlying the exacerbated neuron loss remains elusive. The loss of TDP-43 splicing repression that occurs in presymptomatic ALS-FTD individuals suggests that such early loss could facilitate the pathological conversion of tau to accelerate neuron loss. Here, we report that the loss of TDP-43 repression of cryptic exons in forebrain neurons (CaMKII-CreER;Tardbp f/f mice) is necessary to exacerbate tauopathy-dependent brain atrophy by sensitizing vulnerable neurons to caspase 3-dependent cleavage of endogenous tau to promote tauopathy. Corroborating this finding within the human context, we demonstrate that loss of TDP-43 function in iPSC-derived cortical neurons promotes early cryptic exon inclusion and subsequent caspase 3-mediated endoproteolysis of tau. Using a genetic approach to seed tauopathy in CaMKII-CreER;Tardbp f/f mice by expressing a four-repeat microtubule binding domain of human tau, we show that the amount of tau seed positively correlates with levels of caspase 3-cleaved tau. Importantly, we found that the vulnerability of hippocampal neurons to TDP-43 depletion is dependent on the amount of caspase 3-cleaved tau: from most vulnerable neurons in the CA2/3, followed by those in the dentate gyrus, to the least in CA1. Taken together, our findings strongly support the view that TDP-43 loss-of-function exacerbates tauopathy-dependent brain atrophy by increasing the sensitivity of vulnerable neurons to caspase 3-mediated endoproteolysis of tau, resulting in a greater degree of neurodegeneration in human disorders with co-pathologies of tau and TDP-43. Our work thus discloses novel mechanistic insights and therapeutic targets for human tauopathies harboring co-pathology of TDP-43 and provides a new MED model for testing therapeutic strategies.

Improved Cardiac Rehabilitation Referral Rate Utilizing a Multidisciplinary Quality Improvement Team.

Introduction Cardiac rehabilitation (CR) is an underutilized resource in patients with ischemic heart disease, despite being a Class IA recommendation. In this study, a multidisciplinary quality improvement (QI) team aimed to improve CR referrals by standardizing the ordering process at our hospital system. Method By using a collaborative approach involving the electronic medical record (EMR), medical provider education, and hospital protocols, our two-hospital healthcare system was able to successfully identify barriers to CR referral rates and implement interventions for these barriers. All physicians and medical providers, including ancillary staff, were educated on the EMR order sets to improve compliance by using automated order sets in the EMR. The CR referral order in the EMR included a statement regarding the application of evidence-based medicine, and a computerized provider order entry was included as a reminder to the ordering provider. The use of EMR was monitored monthly by the QI committee. Chi-square test and odds ratios were obtained for statistical analysis. Results Through provider-EMR education and patient education on discharge, CR referral rates significantly improved from 51.2 to 87.1% (p = 0.0001) in a 12-month period. The study included 1,499 patients in total. The improvement was statistically significant regardless of patient gender, race, or insurance coverage. Additionally, subgroup analysis in this study found that prior to standardization of the ordering process, African American patients were significantly less likely to be referred to CR compared to Caucasian patients. (51.2% vs. 41.0%, p=0.01). There was no statistically significant difference in the likelihood of CR referral between Caucasian and African American patients following the intervention (84.0% vs. 78.0%, p = 0.166). Conclusion This study shows that CR is an underutilized resource and that effective QI initiatives may not only increase CR referral rates but also close the gap between racial inequities in referral rates. Future research with multi-center randomized control trials is needed to further enhance its external generalizability to other institutions.

Integrin mechanosensing relies on a pivot-clip mechanism to reinforce cell adhesion.

Cells intricately sense mechanical forces from their surroundings, driving biophysical and biochemical activities. This mechanosensing phenomenon occurs at the cell-matrix interface, where mechanical forces resulting from cellular motion, such as migration or matrix stretching, are exchanged through surface receptors, primarily integrins, and their corresponding matrix ligands. A pivotal player in this interaction is the α5ß1 integrin and fibronectin (FN) bond, known for its role in establishing cell adhesion sites for migration. However, upregulation of the α5ß1-FN bond is associated with uncontrolled cell metastasis. This bond operates through catch bond dynamics, wherein the bond lifetime paradoxically increases with greater force. The mechanism sustaining the characteristic catch bond dynamics of α5ß1-FN remains unclear. Leveraging molecular dynamics simulations, our approach unveils a pivot-clip mechanism. Two key binding sites on FN, namely the synergy site and the RGD (Arg-Gly-Asp) motif, act as active points for structural changes in α5ß1 integrin. Conformational adaptations at these sites are induced by a series of hydrogen bond formations and breaks at the synergy site. We disrupt these adaptations through a double mutation on FN, known to reduce cell adhesion. A whole-cell finite-element model is employed to elucidate how the synergy site may promote dynamic α5ß1-FN binding, resisting cell contraction. In summary, our study integrates molecular- and cellular-level modeling to propose that FN's synergy site reinforces cell adhesion through enhanced binding dynamics and a mechanosensitive pivot-clip mechanism. This work sheds light on the interplay between mechanical forces and cell-matrix interactions, contributing to our understanding of cellular behaviors in physiological and pathological contexts.

Exposure to autoimmune disorders increases Alzheimer's disease risk in a multi-site electronic health record analysis.

Molecular studies of Alzheimer's disease (AD) implicate potential links between autoimmunity and AD, but the underlying clinical relationships between these conditions remain poorly understood. Electronic health records (EHRs) provide an opportunity to determine the clinical risk relationship between autoimmune disorders and AD and understand whether specific disorders and disorder subtypes affect AD risk at the phenotypic level in human populations. We evaluated relationships between 26 autoimmune disorders and AD across retrospective observational case-control and cohort study designs in the EHR systems at UCSF and Stanford. We quantified overall and sex-specific AD risk effects that these autoimmune disorders confer. We identified significantly increased AD risk in autoimmune disorder patients in both study designs at UCSF and at Stanford. This pattern was driven by specific autoimmunity subtypes including endocrine, gastrointestinal, dermatologic, and musculoskeletal disorders. We also observed increased AD risk from autoimmunity in both women and men, but women with autoimmune disorders continued to have a higher AD prevalence than men, indicating persistent sex-specificity. This study identifies autoimmune disorders as strong risk factors for AD that validate across several study designs and EHR databases. It sets the foundation for exploring how underlying autoimmune mechanisms increase AD risk and contribute to AD pathogenesis.

2023 Undetectable = Untransmittable global policy roundtable report: a multistakeholder perspective on Undetectable = Untransmittable research and policy priorities.

Background Launched in 2016 by Prevention Access Campaign, the 'Undetectable=Untransmittable' (U=U) campaign empowers people living with HIV to live full social, sexual and reproductive lives, dismantle stigma, promote increased treatment access, and advocate for updated HIV guidelines. Methods Key priorities for promoting improvements to community-centred, evidence-informed U=U policy and research were the focus of a half-day global roundtable held in 2023 alongside the 12th International AIDS Society Conference in Brisbane, Australia. After a series of presentations, experts in U=U research, policymaking, advocacy and HIV clinical care participated in facilitated discussions, and detailed notes were taken on issues related to advancing U=U policy and research. Results Expert participants shared that knowledge and trust in U=U remains uneven, and is largely concentrated among people living with HIV, particularly those connected to gay and bisexual networks. It was agreed that there is a need to ensure all members of priority populations are explicitly included in U=U policies that promote U=U. Participants also identified a need for policymakers, healthcare professionals, advocates and researchers to work closely with community-based organisations to ensure the U=U message is relevant, useful, and utilised in the HIV response. Adopting language, such as 'zero risk', was identified as crucial when describing undetectable viral load as an effective HIV prevention strategy. Conclusion U=U can have significant benefits for the mental and physical wellbeing of people living with HIV. There is an urgent need to address the structural barriers to HIV care and treatment access to ensure the full benefits of U=U are realised.

Antibiotics for Acute Sinusitis in Children: A Meta-Analysis.

CONTEXT: Acute sinusitis is one of the leading causes of antibiotic prescriptions in children. No recent systematic reviews have examined the efficacy of antibiotics compared with placebo. OBJECTIVE: We sought to determine if antibiotics are superior to placebo in the treatment of acute sinusitis in children. DATA SOURCES: Medline and Embase were searched from their origin to July 2023. STUDY SELECTION: We considered randomized placebo-controlled studies focusing on the treatment of acute sinusitis. In all studies, symptoms were present for <4 weeks and subjects were <18 years of age. DATA EXTRACTION: Two authors independently extracted the data. We pooled data primarily using fixed-effects models. RESULTS: Analysis of 6 included studies showed that antibiotic treatment reduced the rate of treatment failure by 41% (with a risk ratio of 0.59; 95% confidence interval 0.49-0.72) compared with placebo. There was substantial heterogeneity between the studies (I2 = 69.7%), which decreased substantially when the 1 study with a high risk of bias was removed (I2 = 26.9%). Children treated with antibiotics were 1.6 times more likely to have diarrhea than those who were not treated with antibiotics (risk ratio = 1.62, 95% confidence interval 1.04-2.51). LIMITATIONS: A small number of studies were eligible for inclusion. Included studies differed in their methodology. CONCLUSIONS: In children with clinically diagnosed acute sinusitis, antibiotics significantly reduced the rate of treatment failure compared with placebo. However, given the favorable natural history of sinusitis, our results could also support close observation without immediate antibiotic treatment.

Pharmacokinetics of intraarticular liposomal amphotericin B in goats (Capra aegagrus hircus).

Lameness is a significant welfare concern in goats. Amphotericin B is used via intraarticular (IA) administration in models to study experimentally induced lameness in large animals. The main objective of this study was to estimate plasma pharmacokinetic (PK) parameters for amphotericin B in goats after a single IA administration. Liposomal amphotericin B was administered to ten Kiko-cross goats at a dose of 10 mg total (range: 0.34-0.51 mg/kg) via IA administration into the right hind lateral distal interphalangeal joint. Plasma samples were collected over 96 h. Amphotericin B concentrations were measured via liquid chromatography/mass spectrometry (LC-MS/MS). A non-compartmental analysis was used to derive PK parameters. Following single IA administration, maximum plasma concentration was estimated at 54.6 ± 16.5 ng/mL, and time to maximum concentration ranged from 6 to 12 h. Elimination half-life was estimated at 30.9 ± 16.5 h, and mean residence time was 45.1 ± 10.4 h. The volume of distribution after IA administration was 13.3 ± 9.4 L/kg. The area under the curve was 1481 ± 761 h*ng/mL. The achieved maximum concentration was less than the observed concentrations for other species and routes of administration. Further research is needed into the pharmacodynamics of IA liposomal amphotericin B in goats to determine specific research strategies.

Large-scale RNA-seq mining reveals ciclopirox triggers TDP-43 cryptic exons.

Nuclear clearance and cytoplasmic aggregation of TDP-43 in neurons, initially identified in ALS-FTD, are hallmark pathological features observed across a spectrum of neurodegenerative diseases. We previously found that TDP-43 loss-of-function leads to the transcriptome-wide inclusion of deleterious cryptic exons in brains and biofluids post-mortem as well as during the presymptomatic stage of ALS-FTD, but upstream mechanisms that lead to TDP-43 dysregulation remain unclear. Here, we developed a web-based resource (SnapMine) to determine the levels of TDP-43 cryptic exon inclusion across hundreds of thousands of publicly available RNA sequencing datasets. We established cryptic exon inclusion across a variety of human cells and tissues to provide ground truth references for future studies on TDP-43 dysregulation. We then explored studies that were entirely unrelated to TDP-43 or neurodegeneration and found that ciclopirox olamine (CPX), an FDA-approved antifungal, can trigger the inclusion of TDP-43-associated cryptic exons in a variety of mouse and human primary cells. CPX induction of cryptic exon occurs via heavy metal toxicity and oxidative stress, suggesting that similar vulnerabilities could play a role in neurodegeneration. Our work demonstrates how diverse datasets can be linked through common biological features and underscores that public archives of sequencing data represent a vastly underutilized resource with tremendous potential for uncovering novel insights into complex biological mechanisms and diseases.

The Effect of Tranexamic Acid With or Without Tourniquet on Blood Loss in Total Knee Arthroplasty at a Community Hospital.

Tourniquets have long been used in total knee arthroplasty due to the theoretical improvement of bleeding control, integration of cement-bone interface, visibility, and efficiency of the overall surgery. However, this has become increasingly disputed. Comparative studies in total knee arthroplasty employing chemical prophylaxis, i.e., tranexamic acid, have been conducted. This retrospective cohort study evaluated the effect of tranexamic with or without a tourniquet on mean blood loss, hemoglobin, and length of stay in total knee arthroplasty patients. A total of 153 patients' records met the inclusion criteria, 95 patients (62%) were in the tranexamic acid-only group while 58 patients (38%) were in the tranexamic acid plus tourniquet group. Based on mean blood loss in mL (827.5 without vs. 810.1 with the tourniquet, p=0.805), hemoglobin counts in g/dL (12.6 without vs. 12.5 with the tourniquet, p=0.598), and length of stay in days (1.0 days without vs. 1.1 with the tourniquet, p=0.204), there was no statistical difference between the tranexamic alone vs. tranexamic plus tourniquet groups. There were no statistical differences in the mean BMI between groups (32.3 without vs. 32.4 with tourniquets, p=0.901). The patient population had more women (64.1%) than men (35.9%) (p=0.001), but no significant difference in gender based on tourniquet use (p=0.521). The tourniquet group averaged three years younger than the tranexamic alone group (age mean 68.2 without vs 65.3 with tranexamic, p=0.029). This study found no identifiable difference in the three observed variables, indicating that tourniquet provides limited to no additional benefit in reducing blood loss over tranexamic alone in total knee arthroplasty, while tranexamic alone has no deleterious decrease in mean hemoglobin or increase in length of stay.

Effect of Passaging on Bovine Chondrocyte Gene Expression and Engineered Cartilage Production.

Tissue engineering strategies show great potential for repairing osteochondral defects in osteoarthritic joints; however, these approaches often rely on passaging cells multiple times to obtain enough cells to produce functional tissue. Unfortunately, monolayer expansion culture causes chondrocyte dedifferentiation, which is accompanied by a phenotypical and morphological shift in chondrocyte properties that leads to a reduction in the quality of de novo cartilage produced. Thus, the objective of this study was to evaluate transcriptional variations during in vitro expansion culture and determine how differences in cell phenotype from monolayer expansion alter development of functional engineered cartilage. We used an unbiased approach to explore genome-wide transcriptional differences in chondrocyte phenotype at passage 1 (P1), P3, and P5, and then seeded cells into hydrogel scaffolds at P3 and P5 to assess cells' abilities to produce cartilaginous extracellular matrix in three dimensional (3D). We identified distinct phenotypic differences, specifically for genes related to extracellular organization and cartilage development. Both P3 and P5 chondrocytes were able to produce chondrogenic tissue in 3D, with P3 cells producing matrix with greater compressive properties and P5 cells secreting matrix with higher glycosaminoglycan/DNA and collagen/DNA ratios. Furthermore, we identified 24 genes that were differentially expressed with passaging and enriched in human osteoarthritis (OA) genome-wide association studies, thereby prioritizing them as functionally relevant targets to improve protocols that recapitulate functional healthy cartilage with cells from adult donors. Specifically, we identified novel genes, such as TMEM190 and RAB11FIP4, which were enriched with human hip OA and may play a role in chondrocyte dedifferentiation. This work lays the foundation for several pathways and genes that could be modulated to enhance the efficacy for chondrocyte culture for tissue regeneration, which could have transformative impacts for cell-based cartilage repair strategies.

Review of state-of-the-art micro and macro-bioreactors for the intervertebral disc.

Lower back pain continues to be a global epidemic, limiting quality of life and ability to work, due in large part to symptomatic disc degeneration. Development of more effective and less invasive biological strategies are needed to treat disc degeneration. In vitro models such as macro- or micro-bioreactors or mechanically active organ-chips hold great promise in reducing the need for animal studies that may have limited clinical translatability, due to harsher and more complex mechanical loading environments in human discs than in most animal models. This review highlights the complex loading conditions of the disc in situ, evaluates state-of-the-art designs for applying such complex loads across multiple length scales, from macro-bioreactors that load whole discs to organ-chips that aim to replicate cellular or engineered tissue loading. Emphasis was placed on the rapidly evolving more customizable organ-chips, given their greater potential for studying the progression and treatment of symptomatic disc degeneration. Lastly, this review identifies new trends and challenges for using organ-chips to assess therapeutic strategies.

Resource Utilization and Costs Associated with Approaches to Identify Infants with Early-Onset Sepsis.

Objective. To compare resource utilization and costs associated with 3 alternative screening approaches to identify early-onset sepsis (EOS) in infants born at ≥35 wk of gestational age, as recommended by the American Academy of Pediatrics (AAP) in 2018. Study Design. Decision tree-based cost analysis of the 3 AAP-recommended approaches: 1) categorical risk assessment (categorization by chorioamnionitis exposure status), 2) neonatal sepsis calculator (a multivariate prediction model based on perinatal risk factors), and 3) enhanced clinical observation (assessment based on serial clinical examinations). We evaluated resource utilization and direct costs (2022 US dollars) to the health system. Results. Categorical risk assessment led to the greatest neonatal intensive care unit usage (210 d per 1,000 live births) and antibiotic exposure (6.8%) compared with the neonatal sepsis calculator (112 d per 1,000 live births and 3.6%) and enhanced clinical observation (99 d per 1,000 live births and 3.1%). While the per-live birth hospital costs of the 3 approaches were similar-categorical risk assessment cost $1,360, the neonatal sepsis calculator cost $1,317, and enhanced clinical observation cost $1,310-the cost of infants receiving intervention under categorical risk assessment was approximately twice that of the other 2 strategies. Results were robust to variations in data parameters. Conclusion. The neonatal sepsis calculator and enhanced clinical observation approaches may be preferred to categorical risk assessment as they reduce the number of infants receiving intervention and thus antibiotic exposure and associated costs. All 3 approaches have similar costs over all live births, and prior literature has indicated similar health outcomes. Inclusion of downstream effects of antibiotic exposure in the neonatal period should be evaluated within a cost-effectiveness analysis. Highlights: Of the 3 approaches recommended by the American Academy of Pediatrics in 2018 to identify early-onset sepsis in infants born at ≥35 weeks, the categorical risk assessment approach leads to about twice as many infants receiving evaluation to rule out early-onset sepsis compared with the neonatal sepsis calculator and enhanced clinical observation approaches.While the hospital costs of the 3 approaches were similar over the entire population of live births, the neonatal sepsis calculator and enhanced clinical observation approaches reduce antibiotic exposure, neonatal intensive care unit admission, and hospital costs associated with interventions as part of the screening approach compared with the categorical risk assessment approach.

Expanded palette of RNA base editors for comprehensive RBP-RNA interactome studies.

RNA binding proteins (RBPs) are key regulators of RNA processing and cellular function. Technologies to discover RNA targets of RBPs such as TRIBE (targets of RNA binding proteins identified by editing) and STAMP (surveying targets by APOBEC1 mediated profiling) utilize fusions of RNA base-editors (rBEs) to RBPs to circumvent the limitations of immunoprecipitation (CLIP)-based methods that require enzymatic digestion and large amounts of input material. To broaden the repertoire of rBEs suitable for editing-based RBP-RNA interaction studies, we have devised experimental and computational assays in a framework called PRINTER (protein-RNA interaction-based triaging of enzymes that edit RNA) to assess over thirty A-to-I and C-to-U rBEs, allowing us to identify rBEs that expand the characterization of binding patterns for both sequence-specific and broad-binding RBPs. We also propose specific rBEs suitable for dual-RBP applications. We show that the choice between single or multiple rBEs to fuse with a given RBP or pair of RBPs hinges on the editing biases of the rBEs and the binding preferences of the RBPs themselves. We believe our study streamlines and enhances the selection of rBEs for the next generation of RBP-RNA target discovery.

Understanding the etiopathogenesis of lumbar intervertebral disc herniation: From clinical evidence to basic scientific research.

Lumbar intervertebral disc herniation, as a leading cause of low back pain, productivity loss, and disability, is a common musculoskeletal disorder that results in significant socioeconomic burdens. Despite extensive clinical and basic scientific research efforts, herniation etiopathogenesis, particularly its initiation and progression, is not well understood. Understanding herniation etiopathogenesis is essential for developing effective preventive measures and therapeutic interventions. Thus, this review seeks to provide a thorough overview of the advances in herniation-oriented research, with a discussion on ongoing challenges and potential future directions for clinical, translational, and basic scientific investigations to facilitate innovative interdisciplinary research aimed at understanding herniation etiopathogenesis. Specifically, risk factors for herniation are identified and summarized, including familial predisposition, obesity, diabetes mellitus, smoking tobacco, selected cardiovascular diseases, disc degeneration, and occupational risks. Basic scientific experimental and computational research that aims to understand the link between excessive mechanical load, catabolic tissue remodeling due to inflammation or insufficient nutrient supply, and herniation, are also reviewed. Potential future directions to address the current challenges in herniation-oriented research are explored by combining known progressive development in existing research techniques with ongoing technological advances. More research on the relationship between occupational risk factors and herniation, as well as the relationship between degeneration and herniation, is needed to develop preventive measures for working-age individuals. Notably, researchers should explore using or modifying existing degeneration animal models to study herniation etiopathogenesis, as such models may allow for a better understanding of how to prevent mild-to-moderately degenerated discs from herniating.

Priming chondrocytes during expansion alters cell behavior and improves matrix production in 3D culture.

OBJECTIVE: Cartilage tissue engineering strategies that use autologous chondrocytes require in vitro expansion of cells to obtain enough cells to produce functional engineered tissue. However, chondrocytes dedifferentiate during expansion culture, limiting their ability to produce chondrogenic tissue and their utility for cell-based cartilage repair strategies. The current study identified conditions that favor cartilage production and the mechanobiological mechanisms responsible for these benefits. DESIGN: Chondrocytes were isolated from juvenile bovine knee joints and cultured with (primed) or without (unprimed) a growth factor cocktail. Gene expression, cell morphology, cell adhesion, cytoskeletal protein distribution, and cell mechanics were assessed. Following passage 5, cells were embedded into agarose hydrogels to evaluate functional properties of engineered cartilage. RESULTS: Priming cells during expansion culture altered cell phenotype and chondrogenic tissue production. Unbiased ribonucleic acid-sequencing analysis suggested, and experimental studies confirmed, that growth factor priming delays dedifferentiation associated changes in cell adhesion and cytoskeletal organization. Priming also overrode mechanobiological pathways to prevent chondrocytes from remodeling their cytoskeleton to accommodate the stiff, monolayer microenvironment. Passage 1 primed cells deformed less and had lower yes associated protein 1 activity than unprimed cells. Differences in cell adhesion, morphology, and cell mechanics between primed and unprimed cells were mitigated by passage 5. CONCLUSIONS: Priming suppresses mechanobiologic cytoskeletal remodeling to prevent chondrocyte dedifferentiation, resulting in more cartilage-like tissue-engineered constructs.

Prevalence of HIV drug resistance among adolescents receiving ART in Cameroon with low- or high-level viraemia.

OBJECTIVES: To characterize HIV drug resistance (HIVDR) below and above the WHO threshold of 1000 copies/mL, considered for the definition of HIV ART failure in resource-limited settings. METHODS: From a cohort of 280 adolescents (aged 10-19 years) receiving ART for at least 6 months, genotypic resistance testing (GRT) was attempted for two groups of participants: participants with low-level viraemia [LLV; viral load (VL) 200-999 copies/mL] and those in virological failure (VF; confirmed VL ≥1000 copies/mL) using an in-house method. The Stanford HIValg Program was used to identify relevant HIVDR mutations and predict the efficacy of the newly introduced tenofovir-lamivudine-dolutegravir combination. RESULTS: GRT was successfully performed in 54/58 (93.1%) eligible participants, of which 28/31 (90.3%) were in VF and 26/27 (96.3%) had LLV. A high level of resistance was found both in adolescents with LLV and those in VF, with respectively 84.6% (22/26) and 75.0% (21/28) of participants harbouring at least one HIVDR mutation. NRTIs and NNRTIs were the most affected drug classes in both population groups. In contrast, PIs were not significantly affected and dolutegravir was expected to be active for all participants tested. However, for the newly introduced dolutegravir-based combination, functional monotherapy (dolutegravir only) was potentially possible for 22.7% (5/22) of the participants with LLV. CONCLUSIONS: Our findings show that the 1000 copies/mL threshold is not an indicator of virological success and we call for a revision of the current WHO definition of VF in resource-limited countries.

Impact of Obesity on Outcomes of Emergency Department Visits for Cardiac Chest Pain: Insights From a Nationwide Emergency Department Study.

Background Obesity, a widespread national epidemic that impacts one in three U.S. adults, is closely linked with the development and exacerbation of cardiovascular disease. The objective of this study was to assess and contrast the outcomes of adults, both obese and non-obese, who present with cardiac chest pain in the emergency department (ED). Methodology A retrospective analysis of the 2020 Nationwide Emergency Department Sample database was conducted. Multivariate regression models were utilized to examine the association between obesity and mortality, discharge disposition, number of procedures, complications, and hospital costs. Results No significant difference in mortality odds was observed between obese and non-obese patients presenting with cardiac chest pain in the ED (adjusted odds ratio (aOR) = 0.92; 95% confidence interval (CI) = 0.59-1.46; p = 0.736). However, obesity was found to be associated with a decreased likelihood of being discharged home from the ED (aOR = 0.57; 95% CI = 0.52-0.63; p < 0.001), as well as an increased likelihood of hospital admission from the ED (aOR = 1.66; 95% CI = 1.53-1.81; p < 0.001). Obesity also correlated with higher odds of non-home discharge (aOR = 1.74; 95% CI = 1.54-1.97; p < 0.001), elevated mean total hospital costs (mean = $13,345 vs. $9,952; mean increase = $3,360; 95% CI = $2,816-$3,904; p < 0.001), and increased risks of cardiac arrests (aOR = 1.52; 95% CI = 1.05-1.88; p < 0.001) and acute respiratory failures (aOR = 1.43; 95% CI = 1.25-1.96; p < 0.001). Obese patients with cardiac pain underwent more procedures on average than non-obese patients (19 vs. 15; aOR = 3.57; 95% CI = 3.04-4.11; p < 0.001). Conclusions Obesity is associated with higher odds of hospital admission from the ED, non-home discharges, higher total hospital costs, and a greater number of procedures.