Transplants of fresh and cryopreserved autologous adipose tissue improve reintegrative phenomena in newly formed muscle tissue in the reconstruction of muscle volume loss: A histological evaluation

Abstract Repair of volumetric muscle loss (VML) lesions tends to be poor, leading to fibrosis and functional loss. Here we investigated the effectiveness of fresh versus cryopreserved autologous adipose tissue transplantation to facilitate repair. Wistar rats were distributed into four experimental groups: normal control, VML lesions, VML lesions treated with a fresh autologous adipose tissue graft, and VML treated with a cryopreserved autologous adipose tissue graft. At 60 days post‐intervention, a histological, histochemical, and immunohistochemical analysis was performed to assess changes related to the degree of fibrosis, vascularization, and innervation. These changes were quantified and statistically analyzed. The changes generated by the two types of adipose tissue implanted in the VML lesion were highly similar, with some significant differences favoring the use of cryopreserved adipose tissue. Compared with the VML group, the following outcomes were observed: (1) significant presence of regenerated muscle fibers; (2) significant reduction of fibrosis, albeit with a higher proportion of type III collagen; (3) significant increase in the microvascular pattern; and (4) significant reduction in the number of angulated atrophic muscle fibers and increase in cytoarchitectural changes indicative of reinnervation. This study suggests that autologous adipose tissue transplantation in VML lesions promotes reintegrative processes, facilitating the regeneration and formation of new muscle fibers. Furthermore, the freezing did not diminish outcomes in the CAAT group, highlighting its potential for preservation in tissue banks and applications in regenerative medicine.

Peptides Derived From Reactive Center Loops Inhibit Digestive Trypsin‐Like Enzymes in Lepidopteran Pests

ABSTRACT Soybean yield is often reduced by pest attacks. Among these, Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae) stands out as one of the most important defoliating pests of soybean. Therefore, the development of new bioinsecticides targeting Lepidopteran pests is an urgent need. Protease inhibitors (PIs) have emerged as promising molecules in this context. In this study, we designed four peptides (TGPCK, TGPCR, AVIMK, and AVIMR) inspired by the reactive center loops of BPTI and SKTI to assess their potential as competitive inhibitors of trypsin‐like proteases in A. gemmatalis . In silico and kinetic analyses revealed that peptide binding affinity was influenced by specific chemical interactions, with pi‐sigma bonds correlating with higher affinity for AVIMK, while alkyl/pi‐alkyl and C‐H bonds were associated with lower affinity for AVIMR and TGPCK. Key residues (His57, Asp102, Ser195, Asp189, S195, and G197) played a crucial role in ligand binding. Enzyme inhibition assays confirmed that all peptides acted as competitive inhibitors of A. gemmatalis trypsin‐ glen proteases, with TGPCK displaying the highest efficacy. These findings highlight BPTI‐derived peptides as potential candidates for future pest management strategies. Further studies should evaluate their effects when applied to plants, considering possible metabolic interactions and phytotoxicity.

Molecular and Structural Characterization of Foam Proteins from Mahanarva spectabilis (Distant, 1909) (Hemiptera: Cercopidae) Nymphs Reveals Adaptive Features and Potential Targets for Pest Control

ABSTRACT During its nymphal development, the spittlebug Mahanarva spectabilis (Distant, 1909) (Hemiptera: Cercopidae) secretes a persistent extracellular foam that functions as a multifunctional barrier against environmental stressors. In this study, we present a molecular and structural characterization of the foam proteins using LC‐MS/MS and AlphaFold‐based structural modeling. Although no significant differences were observed in total protein concentration across different host plant genotypes, proteomic analyses revealed the down‐regulation of specific high‐abundance proteins in nymphs feeding on resistant/moderately resistant grasses. This suggests a potential impairment of foam functionality and reduced nymphal fitness under field conditions. Peptides from individual SDS‐PAGE bands mapped to multiple distinct unigenes, indicating that proteins encoded by different transcripts share highly conserved sequence motifs, domain architectures, and structural folds. This was particularly evident for the most abundant protein, likely reflecting post‐translational modifications such as signal peptide cleavage, proteolytic processing, or alternative splicing. AlphaFold structural predictions revealed the presence of adhesive and matrix‐related domains, such as WSC, S‐layer, ankyrin repeats, and apolipophorin folds, across several foam proteins. The dominance of extended α‐helices and the predicted dimerization interfaces reinforce the hypothesis that these proteins participate in the formation of supramolecular scaffolds essential for the mechanical stability and adhesion of the foam. Collectively, these findings suggest that M. spectabilis foam proteins have undergone evolutionary specialization to assemble a multifunctional extracellular matrix that ensures nymphal protection. These insights highlight potential molecular targets for novel pest control strategies and contribute to the broader understanding of insect‐derived extracellular secretions with biomimetic relevance.

Gené's Organ of Amblyomma sculptum (Acari: Ixodidae): Morphological Aspects on the First Day of Oviposition and Participation in the Lipid Composition of the Egg Wax

ABSTRACT The Gené's organ (GO) secretes a waxy substance on eggs that reduces water loss and has antimicrobial properties. The current study evaluated morphological and histochemical aspects of GO in Amblyomma sculptum on the 1st day of oviposition (DOV), as well as the neutral lipids found in the organ and wax. The morphological results showed that the glandular cells of the GO synthesize proteins. On the other hand, punctually, necrotic glandular cells and mitochondria were noted, with initial signs of degeneration, confirming the beginning of senescence of these cells. The analysis of the neutral lipids showed that the cranial and caudal glands have identical profiles, thus indicating that the individualization between them is simply anatomical. Still, the lipids found in the cranial and caudal glands were the same found in the wax showing that OG has an important function in the final synthesis of egg wax.

Synthetic Peptide Inhibition of Trypsin‐Like Proteases in Spodoptera frugiperda (Lepidoptera: Noctuidae): Evaluating the Influence of Gut Microbiota

ABSTRACT Spodoptera frugiperda J.E. Smith (Lepidoptera: Noctuidae) is a major agricultural pest whose control has been increasingly challenged by resistance to conventional insecticides. Synthetic protease inhibitors represent promising alternatives; however, the potential modulation of their efficacy by gut microbiota remains poorly understood. Here, we evaluated two rationally designed synthetic tripeptides, GORE1 and GORE2, as inhibitors of trypsin‐like digestive proteases and investigated whether gut microbiota disruption alters their inhibitory performance in S. frugiperda . Enzymatic assays revealed competitive inhibition patterns, with K i values of 1.41 mM for GORE1 and 0.49 mM for GORE2. Most treatments increased apparent K M values, indicating reduced substrate affinity, whereas GORE2 consistently showed lower K M values. Despite stronger in vitro affinity (lower K i ), GORE2 did not produce greater biological impairment than GORE1. Microbiota imbalance induced by antibiotic treatment did not significantly alter larval survival or enzymatic inhibition patterns but modulated specific developmental responses, particularly prolonged larval development and reduced body mass under GORE1 exposure. Nutritional indices (ECI and ECD) were significantly reduced in peptide‐treated larvae, supporting impaired protein metabolism. These findings demonstrate that synthetic peptides effectively inhibit trypsin‐like proteases in S. frugiperda and negatively affect larval nutritional performance. Although microbiota disruption did not modify survival or primary enzymatic inhibition, microbiota‐mediated compensatory mechanisms cannot be excluded. Future integrative studies combining microbiome profiling and metabolic analyses will be essential to resolve host–enzyme–microbiota interactions under digestive inhibition.

Clinical Manifestations of VEXAS Syndrome Across a Broad Spectrum of UBA1 Mutation Burden

Objective Vacuoles, E1‐ubiquitin–activating enzyme, X‐linked, autoinflammatory, somatic (VEXAS) syndrome is a progressive systemic autoinflammatory disorder caused by somatic variants in UBA1 in blood. Previous analyses have shown discordant disease penetrance. In this study, we examine the associations between demographic features and UBA1 variant allele frequency (VAF) with disease manifestations. Methods Whole exome sequencing data from 192,584 participants from Geisinger MyCode Community Health Initiative and Mount Sinai Bio Me Biobank were analyzed for disease‐causing variants in UBA1 . Clinical manifestations were analyzed across individuals with the UBA1 variant. Results Nine UBA1 variants (VAF range 2.9%–79%) in 23 participants (69.6% men) were identified. Cases with high VAF (>20%) developed macrocytic anemia more often (87.5%) than patients with low VAF (≤20%) variants (27%; P = 0.009). Specifically, at the time of genetic testing, 87.5% of high VAF cases had macrocytic anemia compared with 13.3% of low VAF cases ( P = 0.001). However, there was no significant difference in the development of anemia or thrombocytopenia ( P = 0.53). In two high VAF cases, macrocytosis developed more than five years before the time of sample collection, followed by anemia approximately at the time of sample collection. In one low VAF case with other inflammatory symptoms, macrocytic anemia did not develop until five years after sample collection. Conclusion VEXAS syndrome disease severity and penetrance increase at higher VAFs. Low VAF cases demonstrate incomplete penetrance, and the disease tends to be milder in those with it. Female individuals are enriched in lower VAFs and have milder symptoms, suggesting a protective role against disease severity. Low VAF cases, especially ≤10%, can be initially asymptomatic and later develop disease.

Distinct Cancer Risk Profiles in Patients With Systemic Sclerosis With Autoantibody Stratification

Objective Patients with systemic sclerosis (SSc) face increased cancer risk compared to the general population, yet current evidence on specific cancer patterns and their relationship to autoantibody status remain poorly characterized. This study seeks to evaluate cancer risk patterns in patients with SSc and investigate associations between specific autoantibodies and cancer development. Methods This multicenter cohort study analyzed five‐year cancer incidences in 66,637 adults with SSc versus matched controls with seborrheic keratosis using electronic medical records from 128 health care organizations (from 2014 to 2024). Patients were stratified by autoantibody status (RNA polymerase III, anticentromere, or anti‐Scl‐70) when available. Primary outcomes included five‐year incidences of hematologic and solid‐organ cancers, with hazard ratios (HRs) calculated via Cox proportional hazards regression. Results Patients with SSc demonstrated elevated five‐year all‐type cancer risk (HR 1.17, 95% confidence interval [CI] 1.11–1.23). Hematologic cancer risk was significantly increased (HR 1.68, 95% CI 1.50–1.88), particularly for multiple myeloma (HR 2.13, 95% CI 1.61–2.81) and myelodysplastic syndromes (HR 2.03, 95% CI 1.49–2.77). For solid‐organ cancers (HR 1.23, 95% CI 1.16–1.31), esophageal cancer showed the highest risk (HR 3.96, 95% CI 2.36–6.65), followed by lung cancer (HR 2.32, 95% CI 2.00–2.69). Among autoantibody subgroups, patients with anti‐Scl‐70 positivity showed increased overall cancer risk (HR 1.40, 95% CI 1.03–1.92) and patients with RNA polymerase III positivity had higher rates of hematologic cancers (HR 2.20, 95% CI 1.10–4.28), whereas patients with anticentromere positivity demonstrated no increased cancer risks. Conclusion Patients with SSc demonstrate significantly increased risks for both hematologic and solid‐organ cancers, with risk profiles varying by autoantibody status. These findings suggest the need for targeted cancer screening strategies in SSc and further research to confirm the generalizability of these findings.

Reply

A Phase 2 Trial of Hydroxychloroquine in Individuals at Risk for Rheumatoid Arthritis

Objective Individuals with serum elevations of anti–cyclic citrullinated peptide (anti‐CCP) antibodies are at increased risk for future rheumatoid arthritis (RA). No pharmacologic interventions have been approved for the prevention of RA in such at‐risk individuals. However, hydroxychloroquine (HCQ) is used without supporting clinical trial evidence. Methods In this phase 2 randomized trial, individuals at risk for RA with anti‐CCP3 ≥2 times the upper limit of normal (ULN) were assigned to receive HCQ or placebo for 12 months, with up to 24 months of postdrug follow‐up. The primary outcome was the development of clinical RA, as defined in the protocol, at 36 months. Secondary outcomes included safety, development of inflammatory arthritis (IA), and participant‐reported joint symptoms. Results Of 144 randomized participants, 71 were assigned to HCQ and 73 to placebo. In the modified intent‐to‐treat population, clinical RA occurred in 21 of 69 (30.4%) participants in the HCQ group and 24 of 73 (32.9%) in the placebo group. The risk of clinical RA at 36 months was 0.336 with HCQ and 0.394 with placebo (difference −0.058; 95% confidence interval −0.336 to 0.220; P = 0.52). Results for IA were similar. The occurrence and severity of joint symptoms were not observed to differ between groups. Adverse event incidence was similar between groups. Conclusion In this trial involving individuals with anti‐CCP3 levels ≥2 times the ULN, 12 months of HCQ did not prevent the development of clinical RA at 36 months.

Reactive Oxygen Species–Induced Modifications of Fibrin Clots as a Link Between Immune Responses and Atherothrombosis in Systemic Lupus Erythematosus

Objective Cardiovascular events are major determinants of morbidity and mortality in systemic lupus erythematosus (SLE), particularly in patients with renal involvement. Although oxidative stress has been implicated in driving vascular and renal damage in SLE, the specific mechanisms remain unclear. This study investigated the potential role of oxidative stress‐induced alterations in fibrinogen structure and function in the pathogenesis of atherothrombosis in SLE. Methods In this cross‐sectional study, we enrolled 144 adult patients with SLE and 90 matched controls. We measured blood leukocyte reactive oxygen species (ROS) production, systemic redox status, and the structural and functional features of purified fibrinogen. Correlations between these parameters and disease activity were also investigated. In vitro experiments to clarify the causal relationships among ROS levels, protein oxidation, and fibrin abnormalities provided mechanistic insights of the observed alterations. Results Patients with SLE showed increased leukocyte ROS production, mainly due to neutrophil NADPH oxidase activation. Interestingly, renal biopsies from patients with SLE with active proliferative lupus nephritis exhibited overexpression of the NADPH oxidase enzyme complex p22phox. This was accompanied by plasma oxidative stress as indicated by elevated plasma lipid peroxidation and reduced antioxidant defenses. Fibrinogen oxidation was associated with structural and functional changes, leading to the formation of denser fibrin networks with lower clot porosity and reduced susceptibility to plasmin‐mediated fibrin lysis. Interestingly, these fibrinogen modifications correlated with alterations in redox status and disease activity. Conclusion Oxidative stress may drive structural and functional modifications of fibrinogen in SLE, potentially acting as a novel pathogenetic mechanism in atherothrombosis among these patients.