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The mevalonate (MVA) pathway is a central metabolic route responsible for the biosynthesis of isoprenoids with broad biological and biotechnological relevance. Due to its importance, the MVA pathway has attracted increasing interest in studies of enzymatic regulation, structural biology, metabolic engineering, and synthetic biology, particularly in fungi. This review provides a comprehensive overview of the MVA pathway, addressing its distribution across different domains of life, evolutionary aspects, and metabolic organization, with emphasis in fungi. Special attention is given to the biochemical and structural characterization of MVA-pathway enzymes, including catalytic mechanisms, structural features, and regulatory processes. The methylerythritol phosphate pathway is also presented as an alternative route for isoprenoid precursor biosynthesis and discussed in terms of its taxonomic distribution and metabolic significance. Recent advances in synthetic biology, enzyme regulation, and pathway engineering are highlighted, emphasizing their contributions to metabolic engineering and synthetic biology. Special emphasis is given to fungi, in which the MVA pathway plays a central role in ergosterol biosynthesis, protein prenylation, and secondary metabolite production. Advances in the engineering of fungal cells, including Saccharomyces cerevisiae and other emerging fungal species, are discussed in the context of sustainable isoprenoid production. Finally, strategies for optimizing microbial production are presented, highlighting the importance of fungal synthetic biology in advancing biotechnological applications. Full article

Microphysiological Systems (MPS) have emerged as a transformative platform in biomedical research, enabling the investigation of disease mechanisms, drug screening, and toxicity prediction by closely simulating human physiological functions. However, the rapid advancement of MPS technology has raised a series of complex ethical challenges. These include the sourcing and application of human-derived stem cells, the protection of donors’ personal and genetic data, the potential for brain organoids to develop consciousness-like characteristics, and the challenges to species boundaries posed by human–animal chimera research. Meanwhile, although regulatory authorities encourage innovation, specialized certification standards and ethical review guidelines for MPS are yet to be fully established. The lack of technical standardization and a coherent ethical governance framework remain a major bottleneck hindering the broader application and industrialization of MPS. This review systematically outlines the key ethical issues facing MPS, compares the evolution and differences in international ethical regulatory frameworks, and discusses strategies for addressing these challenges—including the establishment of dynamic ethical governance mechanisms, harmonization of international standards, and the promotion of benefit-sharing and public engagement. Finally, we highlight the need to develop a scientific, unified, and actionable ethical governance system that balances technological innovation with responsible translation, supporting the sustainable development of MPS technology. Full article

Over time, our understanding of the central nervous system (CNS) as an immunologically privileged site where immune-cell infiltration takes place has changed; research has transformed the dominant view, showing that the CNS is an immunologically specialized tissue featuring complex interactions between the immune system and CNS processes, where the choroid plexus (CP) has an essential role in regulating neuronal tissue homeostasis and immune-cell trafficking. Although immune-cell entry into the CNS is tightly controlled, small numbers of antigen-experienced lymphocytes can access cerebrospinal fluid (CSF) compartments for immune surveillance under normal conditions. During an injury, such as cerebral ischemia or spinal cord damage, dendritic cell precursors infiltrate the CNS, suggesting their involvement in modulating lymphocyte activity. However, the immunoregulatory function of the CP alone is insufficient to prevent damage. Injury can trigger a cascade of events including activation of microglia toward a pro-inflammatory M1 phenotype, infiltration of peripheral immune cells across the blood–brain barrier (BBB), and uncontrolled neuroinflammation. T cells play a critical role in this process. Th1 cells exacerbate inflammation upon recognizing neural antigens, whereas Th2 cells promote recovery by releasing neurotrophic factors. This highlights the dual role of inflammation in CNS injury and repair. Full article

Aspartic proteases (APs), a class of proteolytic enzymes involved in protein maturation, degradation, and signaling, are known to contribute to fungal virulence and pathogenicity. However, the AP gene family in Talaromyces marneffei (T. marneffei), a dimorphic opportunistic pathogenic fungus, has not yet been functionally analyzed. In this study, we identified 27 AP genes from the T. marneffei genome, and the encoded APs retained conserved domains and exhibited similar motifs and structural properties crucial for catalytic activity. Phylogenetic and collinearity analyses found that TmAPs were most recently homologous to Aspergillus gene families, with both tandem and segmental duplications contributing to their expansion. Expression patterns, combined with RNA-sequencing data, revealed the specialized roles of TmAP1 and TmAP2 in the dimorphic conversion between the yeast and mycelial phases. Protein–protein interaction network analysis uncovered links to cell fusion, mitochondrial function, and programmed cell death. Under abiotic stress conditions, several TmAP genes displayed significant transcriptional changes, implying their involvement in short-term adaptation and stress responses. This study provides the first comprehensive and systematic analysis of the AP gene family in T. marneffei, highlighting their potential biological roles in fungal development, dimorphic conversion, and stress adaptation. Our findings offer valuable insights into further functional characterization of AP genes in T. marneffei and may facilitate the development of novel therapeutic targets and intervention strategies against T. marneffei infection. Full article

Bone metastasis develops within a specialized marrow ecosystem where hematopoiesis, immune regulation, vascular trafficking, and skeletal remodeling intersect. Neutrophil-lineage cells occupy a unique position in this setting because they are generated, retained, mobilized, aged, and reprogrammed within the same bone marrow niches that disseminated tumor cells exploit for homing and survival. This review examines how neutrophils, tumor-associated neutrophils, immature neutrophils, low-density neutrophils, and PMN-MDSCs shape skeletal colonization. We discuss tumor-to-marrow signaling, CXCR2-dependent recruitment, CXCR4/CXCL12-mediated marrow retention, neutrophil–circulating tumor cell interactions, vascular arrest, dormancy escape, NET-mediated matrix remodeling, immune suppression, and effects on osteoclast–osteoblast coupling. Evidence is strongest in breast and prostate cancer models, where pathways such as CXCL5/CXCR2, CTNND1–CXCR4/CXCL12, PR3–RAGE, and DKK1–CKAP4–STAT6–CHI3L3 link neutrophil-lineage cells to skeletal progression and immunotherapy resistance. However, several mechanisms, including CTC–neutrophil clustering and NET-driven dormancy awakening, remain partly extrapolated from non-skeletal models. We therefore emphasize evidence hierarchy, methodological limitations, and therapeutic opportunities, arguing that selective reprogramming or functional inhibition of pro-metastatic neutrophil states may be more promising than indiscriminate neutrophil depletion in metastatic bone disease. A clearer understanding of these context-dependent neutrophil programs may help refine biomarker development and guide combination therapies for patients with skeletal metastases. Full article

Remote tele-rehabilitation requires objective pain assessment, but existing approaches fail in two distinct ways. Self-report scales such as the Visual Analog Scale and the Numeric Pain Rating Scale are easy to falsify, opening a special case of the Oracle problem in blockchain-based insurance. Cloud-based computer vision handles falsification but transmits raw biometric video off the patient’s device, violating privacy requirements. A decentralized Edge AI-Oracle architecture is proposed that combines MediaPipe Face Mesh landmark extraction with a recurrent classifier mapping Action-Unit feature sequences to a learned pain score aligned with the Prkachin and Solomon Pain Intensity scale. The recurrent cell is selected empirically across short-context (T = 2) and long-context (T = 120 frames at 24 fps) regimes, with a two-layer Long Short-Term Memory (LSTM) network adopted for deployment. Inference and Elliptic Curve Digital Signature Algorithm (ECDSA) signing run inside an ARM TrustZone Trusted Execution Environment (TEE). Biometric logs are stored off-chain on the InterPlanetary File System (IPFS). Smart contracts anchor results on-chain and open a 24 h optimistic verification window for an off-chain Watchtower auditor. On SynPAIN the LSTM reaches F1 = 0.683 on T = 120 video (leave-one-stratum-out), with a directional but non-significant advantage over Gated Recurrent Unit (GRU) (Wilcoxon p = 0.167). Cross-dataset validation on BioVid Heat Pain Database Part A (87 subjects, 174 paired observations, leave-one-subject-out) yields F1 = 0.519 for LSTM and 0.499 for GRU (Wilcoxon p = 0.549). A processor-only TEE surrogate benchmark estimates 1.96 ms (FP32) and 0.45 ms (INT8) inference latency at T = 120 with a 0.34 MB footprint and 707 µs ECDSA signing latency, leaving the INT8 inference latency more than an order of magnitude below the 33 ms per-frame budget. The dual-layer storage reduces gas costs by a factor of 23.4 (160,261 vs. 3,744,872 gas), corresponding to an illustrative mainnet cost of approximately 0.53 USD per submission at 1 gwei, rising to roughly 16 USD at a busier 30 gwei, and falling to approximately 0.005 USD on Arbitrum One (April 2026 reference parameters), so that continuous monitoring is economically practical on Layer-2. An adaptive-adversary analysis of the Watchtower shows that gross score tampering is detected at every usable operating threshold, whereas a rational adversary who inflates by less than the dispute threshold, or who shapes the injected score to fall just inside it, evades detection. Because the false-positive rate reaches zero only for $\mathsf{\delta }\gtrsim 0.15$, the protocol bounds rather than eliminates patient-side fraud and motivates a zero-knowledge proof-of-inference successor. The framework is architecturally and economically feasible as a cryptographically verifiable, privacy-preserving tele-rehabilitation substrate aligned with General Data Protection Regulation (GDPR) and Health Insurance Portability and Accountability Act (HIPAA) requirements through the Zero-Video Transmission principle, while remaining economically viable under post-Dencun mainnet and Layer-2 conditions. Recognition accuracy on real-world data and robustness to small-magnitude tampering remain limitations that the interchangeable recognition and audit components must improve before clinical deployment. Full article

Acinetobacter baumannii, a multidrug-resistant pathogen of critical priority within the ESKAPE group, poses a significant threat to global healthcare, particularly in the context of nosocomial infections. Its pathogenesis is mediated not only by antibiotic resistance determinants but also by a complex repertoire of secreted virulence factors. However, comprehensive characterization of the A. baumannii secretome remains methodologically challenging due to spectral overlap in complex biological matrices. In this study, we applied a hybrid approach integrating size-exclusion chromatography with Raman spectroscopy to deconvolute the cell-free supernatant of A. baumannii. Chromatographic fractionation into seven fractions reduced spectral complexity and enabled the identification of unique metabolic profiles. Fraction 3 exhibited a distinct composition, containing specific markers for phosphatidylserine (~1724 cm⁻¹), cysteine, phosphatidylinositol, and DNA (~770–806 cm⁻¹), as well as CH₂ groups of lipids and amino acids (~1450–1456 cm⁻¹), while lacking signals corresponding to methionine-containing compounds, nucleic acid backbones, and polypeptide backbones characteristic of other fractions. Analysis revealed distinct biochemical specialization across fractions: Fraction 2 was enriched in glutamine/asparagine-associated signals (~990, ~998 cm⁻¹), Fraction 4 contained a unique carotenoid marker (~1154 cm⁻¹), Fraction 6 exhibited a phenylalanine-specific peak (~1104 cm⁻¹), and Fraction 7 demonstrated the highest intensity of cysteine-containing protein, nucleotide, and phospholipid signals. These findings open new avenues for the discovery of biomarkers associated with virulence and antibiotic resistance in A. baumannii. Full article

The Zona Pellucida (ZP) and its structural analogs are evolutionarily ancient extracellular matrix components. These are essential for oocyte protection, species-specific gamete recognition, and prevention of polyspermy across Metazoa. Defined by the conserved ZP-domain—comprising ZP-N and ZP-C subdomains—these glycoproteins self-assemble into fibrillar matrices through tightly regulated polymerization. Mechanisms of the regulated polymerization involve furin cleavage, disulfide bonding, and hydrophobic interactions. Once considered a vertebrate innovation, the canonical ZP-domain— defined by its bipartite ZP-N/ZP-C architecture, eight conserved cysteine residues, and capacity for matrix polymerization—is now recognized as an ancient metazoan extracellular module, with homologs identified in basal lineages including Porifera, Cnidaria, and Placozoa. While ZP-like sequences have been reported in choanoflagellates such as Salpingoeca rosetta, these lack the complete canonical features and are considered distant structural relatives rather than true ZP-modules. There they function in cell adhesion and tissue integrity, suggesting an origin predating the evolution of specialized reproductive coats. Previous phylogenetic analyses across 97 metazoan species have revealed that vertebrate ZP genes arose from ancestral duplications of the canonical ZP-module. Accordingly, they give rise to eight subfamilies (ZP1–ZP4, ZPD, ZPAX, ZPX, ZPY), with lineage-specific expansions, losses, and pseudogenization reflecting adaptations to diverse reproductive strategies. Positive selection in sperm-binding regions of ZP2 and ZP3 drives a rapid adaptive evolution. It underscores coevolutionary arms races with sperm ligands, contributing to reproductive isolation and speciation. In invertebrates such as abalone and insects, ZP-domain proteins mediate analogous functions through lineage-specific elaborations, including tandem repeats and domain shuffling. Post-translational modifications, particularly glycosylation, fine-tune sperm receptor specificity and matrix stability. The functional transition from a general protective barrier in early metazoans to a sophisticated gamete recognition interface in vertebrates exemplifies modular evolution. This synthesis highlights the domain-level deep homology of ZP-domain proteins as a foundational element of metazoan extracellular matrices, repurposed through gene duplication, neofunctionalization, and selection to meet the demands of evolving reproductive modes. These insights bridge evolutionary biology, reproductive medicine, and developmental genetics. However, major gaps remain, including unresolved orthology between vertebrate and invertebrate ZP genes, the relative contribution of glycans versus protein backbone in sperm recognition, and the lack of functional evidence for canonical ZP-domain proteins in insects. Future studies integrating glycoproteomics, single-cell transcriptomics, and CRISPR-based models are needed to resolve these questions. Full article

Celocentesis represents a novel form of invasive pregnancy test that allows the genetic material of the embryo to be tested during the embryonic stage at 6–9 weeks of gestation. The purpose of this narrative review is to present the latest available literature on celocentesis, including its biological basis, technical aspects, diagnostic performance, safety profile, clinical applications, and future perspectives. Available evidence from selected studies conducted in highly specialized centers suggests that the diagnosis of monogenic diseases by celocentesis can achieve high accuracy, with reported success rates ranging from 93% to 99% when combined with molecular testing and selective fetal cell isolation. Similarly, a high level of concordance with conventional prenatal and postnatal diagnostic methods has been reported. The pregnancy loss associated with celocentesis appears to be low and comparable to baseline early pregnancy loss, although current evidence is derived primarily from observational studies and limited clinical series. One of the main benefits of celocentesis is the capability to perform prenatal diagnosis at an early stage of pregnancy, which facilitates more informed decisions about treatment options, minimizes parental anxiety, and allows earlier intervention when required. Moreover, experimental evidence suggests that celocentesis may provide a future platform for intrauterine therapeutic approaches, including stem cells and gene-based therapies, although these applications remain investigational. Despite these promising findings, celocentesis should currently be considered an experimental procedure, as its use remains largely confined to specialized centers and further multicenter studies are required to establish its safety, reproducibility, and broader clinical utility. Full article

Direct methanol fuel cells (DMFCs) have attracted considerable attention recently for various applications ranging from portable ones to transportation. The efficiency of DMFCs depends on the kinetics of anodic and cathodic electrocatalysts. Due to sluggish anodic methanol oxidation reaction (MOR), DMFCs require an effective and bifunctional catalyst for promoting efficient MOR. The state-of-the-art MOR catalysts, such as Pt/C and Pt-Ru/C, have been shown to exhibit reasonable MOR activity; however, the insufficient mass activity and poor stability of carbon-supported catalysts have been a major limitation, requiring an alternative, efficient, electrocatalyst that exhibits high mass and specific activities. In addition, electrocatalysts without any carbon support (self-supported electrocatalysts) further mitigate their poor stability and therefore enhance their durability. In this regard, metal aerogel catalysts, which are entirely composed of metallic networks, recently attained special interest due to their specific advantages over conventional carbon supports, such as high catalyst utilization and improved electronic conductivity and stability. In this review, we systematically reviewed various metal aerogel catalysts developed for MOR since their first discovery in 2009. The metal aerogel demonstrated superior MOR performance relative to carbon-supported commercial catalysts, with enhancements ranging from 2-fold to 22-fold of mass activity. We also statistically compared the mass activity of metal aerogels with traditional carbon-supported, non-carbon-supported, and advanced shape-controlled catalysts and found that metal aerogels exhibited high mass activities compared to other catalyst systems. Therefore, we clearly establish that metal aerogel catalysts possess great potential as efficient MOR catalysts in DMFCs. In addition, we have provided several future research directions and strategies for further development of metal aerogel-integrated DMFC devices. Full article

The paper presents an automated, remotely controlled installation for the continuous-flow disinfection of treated wastewater. The proposed solution ensures the inactivation of microorganisms without heating the fluid and without the use of chemical disinfectants, thus reducing the environmental impact and resource consumption associated with conventional disinfection methods. The destruction of microorganisms is achieved by applying high-intensity electrical pulses, which cause irreversible permeabilization of cell membranes through the phenomenon of electroporation. The installation is fully automated and based on a closed-loop control system, in which a programmable logic controller (PLC) acquires data from specialized sensors and automatically regulates the process variables according to the measured operating conditions. The system implements a closed-loop control strategy, optimizing the amplitude, duration and frequency of the electrical pulses depending on the characteristics of the treated fluid and the working flow rate. By eliminating chemical reagents and limiting thermal effects, the proposed technology contributes to reducing energy consumption and increasing the sustainability of the disinfection process. The integration of electroporation with modern automation and monitoring solutions supports the implementation of circular economy principles and the development of sustainable strategies for the management and reuse of treated wastewater. The proposed PLC-SCADA architecture enables adaptive real-time control of the disinfection process by continuously adjusting pulse amplitude, duration, and repetition frequency according to wastewater characteristics and flow conditions. Compared with conventional chemical disinfection methods, the system eliminates the need for chemical reagents and minimizes the formation of secondary pollutants. In addition, the continuous-flow configuration facilitates integration into existing wastewater treatment infrastructures while supporting sustainable and energy-efficient operation. Full article

The second stomach compartment (C2) of the dromedary camel (Camelus dromedarius) plays an important role in digestion. However, detailed morphological and histochemical data remain limited. This study aimed to investigate the gross anatomy, histological organization, histometric features, and histochemical distribution of muco-substances in C2. The study was conducted on twenty dromedary camels, including fetuses and adults. Gross anatomical observations were performed on eight fresh and fixed specimens, while histological, histometric, and histochemical analyses were carried out on samples from twelve adult camels using routine and special staining techniques to identify neutral and acidic mucins. C2 was the smallest gastric compartment, located on the right side of the abdominal cavity and partially continuous with C1. Its mucosa formed chambered zones supported by prominent longitudinal muscular bands. Histologically, C2 comprised glandular and non-glandular regions. The glandular mucosa contained gastric pits and branched tubular glands with mucous, chief, and parietal cells, whereas the non-glandular region was lined by keratinized stratified squamous epithelium. Submucosal lymphoid aggregations were observed near the C2–C3 junction. Histometric analysis revealed a markedly developed tunica muscularis. Strong PAS and Alcian blue reactions indicated abundant neutral and acidic mucins. These findings demonstrate that C2 is a structurally specialized compartment supporting digestion, mucosal immune defense, and adaptation to arid environments, clearly distinguishing it from the reticulum of true ruminants. Full article

The voltage-dependent anion channel (VDAC) is the primary conduit for ion and metabolite transport across the mitochondrial outer membrane. Positioned at the interface between the cytosol and the mitochondrial compartment, VDAC is uniquely accessible to proteins on both sides of the membrane, making it an interaction hub whose biophysical properties and signaling functions are shaped by protein complexation in addition to its intrinsic pore specialization. Mammals express three isoforms—VDAC1, VDAC2, and VDAC3—sharing a conserved β-barrel scaffold with about 70% identity. However, minor differences in the sequence lead to drastic changes in VDAC isoform affinity with other proteins. Here, we review the molecular mechanisms and physiological consequences of VDAC complexation with a set of well-characterized partners: hexokinase, dimeric tubulin, α-synuclein, mitochondria-associated membrane proteins, B-cell lymphoma 2 (BCL-2) family proteins, and the translocase of the outer membrane (TOM) protein import complex. For each complex, we evaluate the available structural, biophysical, and genetic evidence for isoform specificity, highlight where mechanistic understanding is most advanced, and identify open questions. A consistent principle emerges across all complexes: functionally nonredundant isoform contributions are primarily governed by differential partner affinity and complexation, rather than by differences in pore architecture alone. This framework has direct implications for mitochondria-associated pathologies, including cancer, cardiovascular disease, and neurodegeneration, as well as for the rational design of VDAC-targeting therapeutics. Full article

“Immature” or “late-maturing” neurons exist in layer II of the cerebral cortex (cortical immature neurons; cINs) and within the amygdaloid complex (subcortical immature neurons; scINs). These cells remain in a prolonged state of arrested development yet retain the ability to resume maturation and to functionally integrate into neural circuits. Both cINs and scINs are abundant in large-brained mammals with respect to small-brained, lissencephalic rodents. In previous reports, using a comparable method for quantification in diverse mammals, including mice, chimpanzees, and other species, we showed positive correlation of immature neuron cell density with brain size and gyrencephaly. Here, we quantified the cINs and scINs in the cerebral cortex and amygdala of young adult rhesus macaques to determine how they compare to phylogenetic variation. Our results further demonstrate the existence of covariance between cIN density and both increasing brain size and neocortical expansion, as well as the specialized increase of scINs in the amygdala of primates. These findings support the emerging view that immature neurons may represent a reservoir of undifferentiated (stem cell-independent) neuronal cells for the widely expanded cortices and amygdala of mammals endowed with high-order cognitive functions and complex sociality. The detailed mapping of cortical and subcortical immature neurons in a primate often used in translational research sets the foundation for deeper, functional studies aimed at understanding human brain plasticity. Full article

Newborn screening initiatives have the potential to mitigate childhood morbidity in Africa, but they also have special ethical, legal, and social implications (ELSI) that are influenced by issues with the health system, cultural diversity, and limited resources. This scoping review explores the ELSI of newborn screening across Africa to identify key challenges, gaps, and future research needs. A systematic search identified 27 peer-reviewed studies published between 2008 and 2025, covering 12 African countries. Data were extracted on study characteristics, disease types, and ELSI dimensions from African Journals Online (AJOL), Scopus, PubMed, Web of Science, and BMJ Journals. Thematic analysis mapped recurring ethical, legal, and social concerns. Most studies examined ethical and social dimensions, while legal frameworks were rarely addressed. South Africa, Tanzania, and Ghana contributed the largest number of publications. Sickle cell disease (52%) and hearing screening (30%) were the dominant foci. Common ethical issues included informed consent, privacy, and justice; legal gaps centered on the absence of data protection and frameworks; and social concerns involved stigma, awareness, and cultural perceptions of hereditary disease. Ethical and social issues dominate NBS discourse in Africa, whereas legal oversight remains limited. To guarantee fair, reliable, and long-lasting newborn screening programs, national policy guidelines, community involvement, and context-specific ethical frameworks must be strengthened. Full article