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Association of lipoprotein-associated phospholipase A2 with recurrence risk and its predictive value in large artery atherosclerotic stroke.

OBJECTIVE: To investigate the association of lipoprotein-associated phospholipase A2 (Lp-PLA2) with large artery atherosclerotic (LAA) stroke and its predictive value for recurrence. METHODS: We consecutively enrolled 412 acute LAA stroke patients. Using a cutoff of 200&#xa0;ng/mL, patients were divided into high and low Lp-PLA2 groups, and into recurrence and non&#x2011;recurrence groups based on 1&#x2011;year follow&#x2011;up. Baseline characteristics, lipid profiles, National Institutes of Health Stroke Scale (NIHSS) scores, and vascular stenosis degree were compared. Binary logistic regression and Receiver Operating Characteristic (ROC) analysis were used to identify independent risk factors and evaluate predictive value. RESULTS: The high Lp-PLA2 group had significantly higher low-density lipoprotein cholesterol (LDL-C), small dense low-density lipoprotein cholesterol (sdLDL-C), prevalence of severe stenosis (&#x2265;70%), and proportion of NIHSS&#xa0;>&#xa0;15 (all P&#xa0;<&#xa0;0.05). The recurrence group showed elevated Lp-PLA2, higher LDL&#x2011;C and sdLDL-C, more severe neurological deficits, and more severe stenosis (all P&#xa0;<&#xa0;0.001). Multivariable regression identified elevated Lp-PLA2 (per 10&#xa0;ng/mL: OR&#xa0;=&#xa0;1.139, 95% CI: 1.089-1.191), moderate (OR&#xa0;=&#xa0;3.145) and severe (OR&#xa0;=&#xa0;11.663) neurological deficits, and severe stenosis (OR&#xa0;=&#xa0;9.390) as independent risk factors for recurrence (all P&#xa0;<&#xa0;0.05). The Area Under the Curve (AUC) of Lp-PLA2 was 0.75 (95% CI: 0.69-0.82), with an optimal cutoff of 208.95&#xa0;ng/mL. CONCLUSION: Elevated Lp-PLA2 is associated with adverse lipid profiles, more severe neurological deficits, and greater vascular stenosis in LAA stroke patients, and independently predicts 1&#x2011;year recurrence. Lp-PLA2 shows moderate predictive value, supporting its potential for risk stratification.

Humans

Secretory Phospholipase A2 in Patients With Sickle Cell Disease Hospitalized for Vaso-Occlusive Pain Episodes.

BACKGROUND: Secretory phospholipase A2 (sPLA2) is an inflammatory mediator linked to acute chest syndrome (ACS) in sickle cell disease (SCD), a serious complication that can develop during an acute vaso-occlusive pain episode (VOE). Plasma sPLA2 levels have been proposed as a potential biomarker for predicting ACS onset. OBJECTIVE: To assess serial plasma sPLA2 levels in 105 pediatric patients hospitalized for SCD-VOE and determine the effects of arginine therapy compared to placebo. PROCEDURES: This is a pharmacokinetics/pharmacodynamics and randomized controlled trial of intravenous arginine therapy. Statistical methods included t-tests, chi-square, and correlation analyses. RESULTS: Mean age was 12.7 &#xb1; 3.7 years, 48% were male, 67% had Hb-SS, and 70% were prescribed hydroxyurea. Using a previously established SCD-specific cutoff of 48&#xa0;ng/mL, presenting sPLA2 levels were elevated in 33% of patients (mean sPLA2 level 85.7 &#xb1; 32.9&#xa0;ng/mL). SPLA2 elevation in the emergency department was more common in patients with ACS compared to those without ACS (64%&#xa0;vs. 30%; p = 0.02; negative predictive value of 94%). Peak sPLA2 levels were significantly higher in febrile (n = 34) versus afebrile patients (n = 71;101.0 &#xb1; 45.3 vs. 48.7 &#xb1; 35.4&#xa0;ng/mL; p < 0.0001). Among subjects with elevated baseline sPLA2, arginine therapy resulted in a significant reduction in sPLA2 levels by discharge compared to placebo (-27.8 &#xb1; 38.1&#xa0;ng/mL; p = 0.002; n = 23&#xa0;vs. -15.0 &#xb1; 41.2&#xa0;ng/mL; p = 0.23; n = 12). CONCLUSIONS: SPLA2 is an underutilized biomarker of ACS given accumulating evidence of its role. In particular, low levels may identify patients at low risk for ACS. Arginine therapy may modulate inflammation in patients with SCD during VOE and/or ACS. TRIAL REGISTRATION: ClinicalTrials.gov identifiers: NCT02447874; NCT02536170.

Humans

Intraspecific variation in Bothrops neuwiedi snake venom: Influence of age and sex.

Snake venom is a complex mixture of molecules and is subject to intraspecific variations due to the influence of abiotic and/or biotic factors, one of which is the animal's ontogeny. Some studies have already shown the influence of age on the composition and properties of snake venom, but these variations are not uniform, and each species may exhibit a specific pattern of variation. Therefore, this study aimed to analyze the influence of age on the venom of Bothrops neuwiedi, using 5 age groups, differentiating between males and females. To this end, we analyzed the protein profile of these venoms (using SDS-PAGE, HPLC, and proteomic analyses); enzymatic activities (PLA2, LAAO, and proteolytic activities); coagulant activity, in vivo assays (MDH; LD50 and ED50), and immunorecognition tests (Western blotting and ELISA). Protein profile analysis showed that males exhibited a gradual increase in SVMP and PLA2 concentrations. Both sexes showed a decrease in CTL concentration and a loss of PLA2 activity, which occurred more gradually in males. Proteolytic activity did not show clear ontogenetic differences, but both sexes showed activity peaks in the 2-year-old and senile groups, with females exhibiting higher proteolytic activity than males. Regarding LAAO activity, it increased in males and decreased in females. Although the LD50 did not show age-dependent differences, the venom from the 1-year-old group took longer to cause death in mice but showed a higher hemorrhagic activity than seniles. Furthermore, more antivenom was needed to neutralize the venom from the 1-year-old group than the venom from the senile group; despite this, immunorecognition tests did not show significant ontogenetic variations. In conclusion, the venom of the snake B. neuwiedi undergoes ontogenetic variations with certain sexual differences, showing some peculiarities that have not been found in ontogenetic analyses of other species of the same genus.

Animals

Integrated transcriptomic and metabolomic analysis of fluoride tolerance-related pathways and differentially expressed genes in silkworm strain XSKD.

XueSong KD (XSKD) silkworm strain exhibits prominent fluoride tolerance, yet the underlying molecular mechanisms of fluoride tolerance remains unclear. In the present study, fourth-instar pre-molting XSKD silkworms were used as experimental materials for integrated transcriptomic and untargeted metabolomic analyses. In total, 572 differentially expressed genes and 90 differential metabolites were screened. GO enrichment and KEGG enrichment based on the hypergeometric distribution model revealed that 13-Hydroxy-9Z,11E-octadecadienoic acid (13-(S)-HODE) acts as the core differential metabolite, which is significantly enriched in the linoleic acid metabolism pathway. Within this pathway, LOC101737302 and CYP338A1 display opposite expression trends and show correlations with pathway metabolites. Based on multi-omics data, this study preliminarily characterizes the lipid metabolic response under fluoride stress, providing omics dataset support for further in-depth exploration of the molecular mechanism of fluoride tolerance in silkworms.

Animals

Mitochondrial DNA diversity in Ecuadorian populations: Recurrence of variant 16136 within haplogroup B2.

The identification of lineage-defining variants, frequently found in the coding region of mitochondrial DNA (mtDNA), is essential for refining haplogroup classification. Most mtDNA studies in South American populations have focused on the control region (CR), which has provided important insights into population structure and maternal lineage origins, although information needed for more robust phylogenetic resolution has been neglected. This study investigates the maternal genetic structure of Ecuadorian populations by combining CR and whole mitogenome analyses. Sequences from the mtDNA CR were obtained from 461 individuals (253 Mestizos and 208 Native Americans), while complete mitogenomes were sequenced for 127 individuals to improve phylogenetic resolution by identifying lineage-defining variants present in coding region. Most mtDNA haplogroups in the two population groups analyzed were of Native American origin (A2, B2, B4, C1, D1, D4), with significant differences in the distribution of specific lineages between them. Among Mestizos, African haplogroups (all within the L branches) and Eurasian haplogroups (H, K, R, U) were detected at low frequencies, whereas no African lineages were observed among Native Americans. The results obtained highlighted a heterogeneity within Ecuadorian populations that must be considered when developing mtDNA haplotype databases for forensic purposes. Whole mitogenome sequences enabled the identification of variants that refined haplogroup classifications, provided a more accurate reconstruction of the maternal genetic diversity, and improve the discrimination between Native American and Asian maternal lineages within haplogroup B4b.

Humans

Venomous Lepidoptera: defensive toxin systems, venom composition, and clinical significance.

Venomous Lepidoptera constitute an underrecognized yet medically significant group of toxin-producing arthropods that employ contact-mediated defensive envenomation through specialized integumentary structures such as setae, spines, and scoli. Unlike actively stinging arthropods, these insects deliver venom passively upon contact, eliciting a diverse spectrum of clinical manifestations collectively termed lepidopterism. Clinical outcomes range from localized pain and dermatitis to severe systemic effects, including hemorrhagic syndromes, complement activation, and chronic inflammatory disorders. Recent advances in proteomic and transcriptomic technologies have transformed our understanding of lepidopteran venoms, revealing unexpectedly complex toxin repertoires comprising serine proteases, phospholipases, pore-forming proteins, disulfide-rich peptides, neuroactive RF-amide peptides, and immune-modulating components. These findings have provided new insights into the molecular basis of toxicity, host-pathogen interactions, and the evolutionary diversification of venom systems within Lepidoptera. This review synthesizes current knowledge on the morphology of venom-delivery structures, venom composition, mechanisms of action, and associated clinical manifestations, while highlighting medically important taxa, particularly species of the genus Lonomia. The successful development of antivenom against Lonomia envenomation underscores the translational relevance of lepidopteran toxin research and its potential for therapeutic innovation. By integrating molecular, clinical, and evolutionary perspectives, this review repositions venomous Lepidoptera as a legitimate and important component of arthropod toxinology. Furthermore, it identifies critical methodological limitations and key knowledge gaps, providing a framework for future investigations aimed at advancing our understanding of toxin biology, immunopathology, and the development of novel biomedical applications.

Animals