Defective viral genomes (DVGs) are generated during the genomic replication of many RNA viruses. When produced early in infection or supplemented at the onset of infection, DVGs can attenuate viral pathogenesis by stimulating interferon responses and antagonizing wild type (WT) virus replication, highlighting their potential as antiviral therapeutics. However, during natural infection DVGs can exert both antiviral and proviral effects depending on their generation kinetics, species, and abundance, underscoring the need to better understand their roles in viral pathogenesis. Coronaviruses (CoVs) are RNA viruses that ubiquitously generate DVGs, yet the roles of DVGs during CoV infection are largely unknown. In a previous study we investigated SARS-CoV-2 DVG presence in vitro and in patient samples and discovered two major genomic hotspots (A and B) for their generation. Here, we first showed that overall DVG abundance tended to positively correlate with COVID-19 severity, with approximately 40% of DVGs originating from a specific genomic region designated hotspot B. Analysis of a publicly available single-cell RNA-seq dataset revealed that DVGs from hotspot B, but not hotspot A, were associated with elevated interferon responses, suggesting that DVGs derived from different genomic regions vary in their ability to stimulate innate immunity. To test this directly, we constructed two representative DVGs corresponding to hotspots A and B. Both DVGs suppressed the replication of co-infecting WT virus; however, only DVG-B induced robust interferon responses, exceeding those triggered by WT virus alone. This was further confirmed in human precision-cut lung slices. Mechanistically, DVG-B-derived dsRNA exhibited a distinct subcellular distribution compared to WT virus. Complementation with the nucleocapsid (N) partially restored dsRNA organization but did not alter the interferon response. Together, our findings demonstrate that DVGs arising from distinct genomic hotspots differentially regulate interferon responses, and N plays a unique role in regulating dsRNA distribution and interferon responses.

Chronic spontaneous urticaria (CSU) is characterized by the idiopathic appearance of wheals and/or angioedema lasting more than six weeks. There is a critical need to evaluate whether the severity of CSU influences the risk of future immune-mediated comorbidities. We aim to evaluate if patients with moderate-to-severe chronic spontaneous urticaria (CSU) have an increased risk of developing immune-mediated comorbidities compared with matched patients with mild CSU. We conducted a retrospective cohort study using the TriNetX US Collaborative Network database from 2014-2026. We propensity matched patients with ≥2 ICD-10 diagnoses of idiopathic urticaria treated with omalizumab, dupilumab, or cyclosporine (moderate-to-severe disease) to age-, sex-, race-, ethnicity-, comorbidity-, and family history-matched counterparts who were never treated with biologics or cyclosporine (mild disease). After matching, 16,413 patients were included in the moderate-to-severe group, and 16,413 patients were included in the mild group. Patients with moderate-to-severe CSU had a significantly increased risk of developing rheumatoid arthritis OR=1.34 (95% CI: 1.12 to 1.60, p = 0.001) and Sjögren's syndrome OR=1.04 (1.63-2.56, p < 0.0001), after adjusting for clinical factors and multiple hypothesis testing (Bonferroni's alpha ≤0.00333). Moderate-to-severe CSU is associated with an increased risk of rheumatoid arthritis and Sjögren's syndrome compared to mild CSU.

Background/Objectives: Systemic inflammation-derived indices, including the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII), have been proposed as convenient and cost-effective predictive markers of mortality and complications in patients with pulmonary embolism (PE). We aimed to evaluate the prognostic performance of hematological inflammatory indices for in-hospital adverse outcomes among Mongolian patients diagnosed with PE. Methods: This multicenter retrospective study enrolled patients admitted to three tertiary-level hospitals in Ulaanbaatar, Mongolia, with a confirmed diagnosis of PE between September 2019 and January 2025. Data were collected retrospectively from electronic medical records. We calculated the NLR, PLR, and SII using standard formulas. All patients were stratified according to the sPESI. Moreover, we determined the prognostic performance of hematological indices for in-hospital adverse events. Results: We analyzed information on 232 patients with a confirmed diagnosis of PE. According to sPESI scoring, 69.8% (162) were in the high-risk group, with significant differences in comorbidity and age over 60 years (p < 0.001). The most common symptoms were dyspnea, chest pain, cough, leg pain, and hemoptysis. The median NLR was 2.48 (1.66-5.08) in the low-risk group and 4.21 (2.04-11.35) in the high-risk group (p = 0.001). The median SII level was significantly higher in the high-risk group than in the low-risk group (p = 0.037). However, there was no significant difference in PLR level between the two study groups. ROC analysis of hematological indices for predicting in-hospital adverse outcomes was limited, with poor and non-significant discriminatory performance. Conclusions: In cases of acute pulmonary embolism, elevated inflammatory indices, NLR and SII, were associated with higher sPESI risk stratification. However, their probability to predict in-hospital adverse events was limited by ROC analysis.

Swine are a crucial species in influenza A virus (IAV) ecology, capable of supporting replication and consequently evolution of human, avian, and swine strains. They are also the source of the 2009 pandemic H1N1 virus (H1N1pdm09). Understanding how swine IAV breach the species barrier is essential for detection of potentially pandemic viruses, but is often overlooked compared to avian IAV. We hypothesize that the HA-NA balance of (pre)pandemic swine viruses is a key feature that needs adjustment as swine and humans differ in their sialoglycome. We focused on a set of (pre)pandemic swine viruses collected in Mexico following the H1N1pdm09 emergence. Phylogenetic analysis showed that the emergence was preceded by substitutions in HA and NA predicted to affect their function. Thus, HA acquired substitution A227E, previously shown to reduce receptor binding in H1N1pdm09, while NA obtained substitution S369N in the 2nd sialic acid binding site (2SBS) predicted to reduce NA cleavage. The substitutions' effect on the HA-NA balance, was confirmed with biolayer interferometry using recombinant proteins attached to nanoparticles. Engineering recombinant attenuated influenza viruses with swine HA and NA with/without the mentioned substitutions, showed that the 2SBS substitution negatively affected replication in primary human and swine cultures. Interestingly, replication was restored by the HA substitution. Overall, we show that the emergence of H1N1pdm09 in humans was preceded by substitutions in HA and NA that were acquired in swine and adjusted the HA-NA balance. We hypothesize that adjustment of the HA-NA balance was a critical step for crossing the host-species barrier.

Early-life enteric infection disrupts the developing microbiota-gut-brain (MGB) axis. Using a neonatal Enteropathogenic Escherichia coli (EPEC) model, we show that intestinal epithelial cell (IEC) nucleotide oligomerization domain (NOD)1 signaling coordinates neuroimmune outcomes throughout early development and into adulthood. Neonatal mice infected at postnatal day (P)7 exhibited ileal inflammation, with increased pro-inflammatory cytokines and monocyte/macrophage infiltration, and loss of myenteric neurons in wild-type mice but not in NOD1 conditional knockout (Nod1ΔIEC) mice. These deficits persisted into adulthood (P56), with increased intestinal permeability, sustained inflammatory/repair signatures, neuroinflammation, altered neurogenesis, and impaired recognition memory, which were absent in Nod1ΔIEC mice, establishing a crucial role for IEC NOD1 in long-term MGB remodeling. Last, bioactive peptidoglycan fragments (muropeptides) were isolated from probiotic Lactobacillus strains and tested as possible therapeutics. Excitingly, supplementation of muropeptides attenuated neonatal EPEC-induced mucosal inflammation and enteric neuron loss without altering bacterial burden, potentially via IEC NOD2. Together, these findings identify IEC NOD-dependent signaling linking early-life enteric infection to enduring gut-brain dysfunction and reveal probiotic-derived muropeptides as candidate therapeutics.

Background: Gastroesophageal reflux and exercise-induced bronchoconstriction (EIB) commonly coexist with asthma, but the effect of exercise on reflux remains unclear. We aimed to assess the prevalence of abnormal impedance-detected acid exposure in children with partially controlled or uncontrolled asthma, its association with EIB, and changes in reflux parameters after an exercise challenge test (ECT). Methods: Thirty patients aged 7-18 years underwent spirometry, treadmill ECT, and 48 h multichannel intraluminal impedance-pH monitoring. EIB was defined as a ≥10% fall in FEV1, and abnormal acid exposure as impedance-detected acid reflux lasting ≥1.2% of recording time. Results: Abnormal acid exposure was identified in 14/30 patients (46.7%), whereas EIB occurred in 6/30 (20.0%), with no significant association between them. The absolute number of reflux episodes was higher after ECT in the count-based analysis (43.0 [35.2-69.8] vs. 33.5 [21.2-54.5], p = 0.006); however, this finding was not confirmed after normalization to analyzable recording time in a sensitivity analysis. Overweight or obesity was present in 9 patients (30.0%) and correlated positively with acid exposure. BMI-for-age z-score correlated positively with acid exposure (ρ = 0.41, p = 0.025), but these findings did not remain significant after correction for multiple testing. Conclusions: Using the prespecified acid-exposure criterion, abnormal acid exposure was frequently identified in this cohort. No statistically significant association with EIB was demonstrated; however, the small number of EIB events limits definitive conclusions. The higher absolute post-ECT reflux episode count was not confirmed in a rate-based sensitivity analysis, and a causal effect of exercise on reflux cannot be established.

Background: The asthma-COPD overlap is widely recognized, but its characteristics are not fully understood. This is largely true for the clinical presentation characterized by various ACO definitions. The purpose of this study was to investigate the pattern of comorbidities among patients with ACO, defined by various criteria. Methods: The data came from the multicenter cross-sectional study conducted in a mixed population of patients with asthma and COPD. Patients were classified into five groups according to five different definitions of ACO (GINA/GOLD/30%, Spanish criteria, COPD + asthma < 40, Gibson's criteria, clinician's diagnosis), reference ACO groups, and a group of patients with obstructive pulmonary diseases who were not diagnosed with ACO. To demonstrate the differences between groups, we compared the prevalence of comorbidities between all ACO and non-ACO groups. Data on age, severity of airflow obstruction, and smoking history were recorded for all patients. Results: For the final analysis, 1609 patients were included. Patients belonging to the ACO groups had a higher burden of comorbidities, poorer lung function, and a higher number of pack-years of smoking history compared to patients without an ACO diagnosis. Comorbidities were significantly more prevalent in ACO groups. Compared to the non-ACO group, nine diseases were more common in the GINA/GOLD/30% group, seven in both the COPD + asthma < 40 group and the clinician's diagnosis group, five in the Gibson's criteria group, and two in the Spanish criteria group. The most common comorbidities in the ACO groups were hypertension, coronary artery disease, GERD, musculoskeletal disorders, diabetes, and chronic sinusitis. Chronic sinusitis was more frequent in ACO groups defined by more precise asthma criteria. Conclusions: The definitions of ACO used in clinical practice vary widely and describe different populations. ACO populations vary in terms of comorbidities, lung function, smoking history, and age. Chronic sinusitis is a comorbidity that occurs more frequently in ACO groups defined by more precise asthma criteria. Patients with ACO differ in their clinical outcomes from those with other obstructive airway diseases.

Ixodid ticks are among the most widespread and permissive groups of arthropod disease vectors in the world. They transmit various viral, bacterial, protozoan, and even nematode pathogens infective for humans and animals. Ticks are essential to studying pathogen transmission and infection in a new host; however, exposing in vivo models to ticks is very challenging. Most current tick placement protocols rely on capsules to increase attachment rates at a specific location. However, capsules interfere with hosts' ability to engage with ticks by grooming/scratching. Conversely, available capsule-free tick infestation protocols, including free-roaming protocols, suffer from low and highly variable tick attachment efficacy. Here, we describe a highly efficient capsule-free nymphal tick placement protocol with tick attachment rates of ≥85% across various tick species and genera, offering the generation of highly reproducible data. This article also offers a set of protocols to the user primarily geared toward the study of itch-induced tick removal but are adaptable to other study settings. Published 2026. This article is a U.S. Government work and is in the public domain in the USA. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Capsule-free, highly efficient multi-species nymphal tick placement for site-specific attachment Basic Protocol 2: Assessing efficacy of itch-induced tick removal by quantifying loss of ticks over time Basic Protocol 3: Assessment of health/ability of partially fed nymphal ticks to feed determined by scutal index Basic Protocol 4: Scratch bout quantification in guinea pigs Support Protocol: Development of a semi-supervised deep learning pipeline for automated detection and validation of scratching behavior Basic Protocol 5: Assessment of local skin inflammation due to immunity to tick bites using laser speckle contrast imaging.

Hydatid cyst-related mortality is rare and diagnostically challenging in forensic practice, particularly when cystic echinococcosis remains clinically unrecognized until death. This study aimed to characterize hydatid cyst-related deaths through integrated assessment of clinical course, macroscopic morphology, histopathology, and mechanism of death. We retrospectively reviewed 32 hydatid cyst-related deaths evaluated by the First Specialized Board of the Council of Forensic Medicine of Türkiye between 2013 and 2024. Demographic and clinical characteristics, organ involvement, macroscopic cyst features, histopathological findings, and certified mechanisms of death were assessed. Macroscopic and histopathological findings were categorized using predefined morphological classifications, and clinicopathological associations were analyzed. The median age was 27.5 years, and 71.9% were male. Hepatic involvement was present in 93.8%, while hydatid disease had not been diagnosed before the fatal event in 84.4%. Anaphylactic shock was the predominant fatal mechanism (59.4%), followed by sepsis/multiorgan failure (21.9%), hydatid-related sudden death without further mechanistic specification (9.4%), pulmonary hydatid embolism (6.3%), and direct cardiac hydatid-related sudden death (3.1%). Intact or tense cysts predominated among macroscopically evaluable cases (73.3%), whereas complete rupture was identified in 16.7%. The secondary infected histopathological phenotype was associated with sepsis-related death (OR 18.0; 95% CI 1.54-210.6; p = 0.025). Hydatid cyst-related deaths occur through distinct clinicopathological pathways, with anaphylactic shock predominating. Complete macroscopic rupture is not required for fatal hypersensitivity reactions. Integrating gross morphology, histopathology, systemic autopsy findings, and clinical context may improve postmortem mechanistic interpretation.

Persistent postural- perceptual dizziness (PPPD) is a functional disorder that is the most frequent cause of chronic dizziness. Diagnostic criteria for PPPD were published by Bárány Society in 2017 and were then included in the International Classification of Diseases, 11th revision (ICD-11). Core symptoms are dizziness, unsteadiness or non-spinning vertigo, lasting more than three months. Persistent symptoms occur without specific provocation, but are exacerbated by upright posture/walking, active or passive motion, and exposure to moving or complex visual stimuli. An acute or episodic vestibular disorder often precedes the onset of PPPD, but conventional vestibular function tests typically show normal results. Studies using resting-state functional MRI have revealed that functional connectivity between the vestibular cortex and visual areas were low, while that between the somatosensory and visual areas was high, suggesting sensory upweighting of visual and somatosensory information. Such central changes have been shown to associate with peripheral hyper-responsiveness as demonstrated by visual stimulus-loaded posturography and head-roll tilt subjective visual vertical testing, which detects visual and neck proprioceptive hypersensitivity, respectively. As a result, symptoms are exacerbated by visual stimulation or somatosensory input associated with body motion. After visual stimulation, gaze stability remains reduced, which would account for the prolonged dizziness induced by visual stimuli. Pharmacological treatments using serotonergic anti-depressants, vestibular rehabilitation, and cognitive behavioral therapy have been shown favorable effects; however, they are not always effective for all patients. There is an urgent need to establish novel treatments tailored to the pathophysiology of PPPD, i.e., sensory upweighting of visual/somatosensory inputs.

This study evaluated the impact of a community-based social media campaign on HIV prevention engagement among Hispanic/Latino gay, bisexual, and other sexual minority men (SMM). The study was conducted at a Latino-serving community-based organization (CBO) in Washington State. We conducted a quasi-experimental pre-post evaluation comparing HIV prevention outcomes among clients observed before the campaign with those observed during the campaign and follow-up period. Propensity score matching was used to compare HIV testing and PrEP use using survey and service-record data. Behavioral determinants were assessed among 76 surveyed clients, including 32 surveyed before the campaign and 45 surveyed during the campaign and follow-up period. Chart-only data from 185 additional clients were also examined to supplement survey findings. The number of Latino SMM engaging in HIV prevention services increased by 114% during the campaign and follow-up period, compared to the same period in the previous year. Propensity score-matched analyses showed that the proportion receiving HIV testing was 6.7 percentage points higher among clients in the post-campaign period than among matched clients observed during the pre-campaign period (p = .039; Cohen's d = 0.22). Findings highlight the potential of culturally tailored, theory-informed social media campaigns to promote HIV prevention among Latino SMM. While effects were modest, the campaign period was associated with a modest increase in HIV testing and demonstrated the potential value of social media for enhancing engagement in community-based HIV prevention services.