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PubMed2026

Investigation of ACE gene polymorphism and serum ACE activity in relation to alopecia areata among Iraqi patients.

BACKGROUND: Alopecia areata (AA) is a multifactorial disorder with immune dysregulation and genetic susceptibility, affecting 0.5-2% globally. OBJECTIVE: This study investigated angiotensin converting enzyme (ACE) gene insertion /deletion (I/D) polymorphism and serum ACE activity in Iraqi AA patients and their association with inflammatory cytokines (interleukin [IL]-17) and nutritional markers to understand disease progression. METHODS: This case-control study included 50 AA patients (Male and Female) and 35 healthy controls. ACE gene polymorphism (rs1799752) was analyzed using real-time polymerase chain reaction (qPCR) with high-resolution melting (HRM) analysis. Serum IL-17 levels were determined by enzyme-linked immunosorbent assay (ELISA), and biochemical markers were measured using an automated analyzer. RESULTS: ACE gene polymorphism (rs1799752) showed non-significant genotype distribution between patient and control groups (p > 0.05), though a trend toward DD genotype enrichment was observed in patients. Serum ACE levels were significantly higher in patients versus controls (p < 0.0001) with high diagnostic performance. ACE correlated positively with IL-17 (P < 0.0001) and negatively with vitamin D3 and zinc (P < 0.0001). Female patients had significantly higher ACE levels than males (P < 0.01). CONCLUSIONS: ACE emerges as an immunometabolic hub in AA pathogenesis, integrating inflammation with nutritional deficits, suggesting its potential as a biomarker and therapeutic target.

Humans↗

PubMed2026

Effectiveness of STK Spray® for semen stain localization on solid surfaces: A specificity and sensitivity study.

Semen identification is a crucial step in sexual assault cases. The aim of this study was to assess STK Spray®, a presumptive test for semen, under controlled conditions including, simulated crime scene stains detection. Easy to use, it can be sprayed directly onto different surfaces and visualized under UV light. Several tests were performed on five different substrates (ceramic tile, drywall, metal, wood, and faux leather). The spray was able to enhance semen fluorescence, especially in diluted samples, with characteristic "globular" spots. Although it showed good specificity, false positives could be obtained with 10% bleach. The fluorescence signals were quantified using ImageJ™ and showed a statistically significant substrate-dependent variability. Mixture analysis indicated that saliva did not interfere with detection of semen, while urine partially suppressed the signal and blood markedly affected its interpretation. Simulation tests with UV lamp comparisons confirmed the importance of choosing the right detection method and the utility of this presumptive test in combination with additional immunochromatographic tests. A preliminary signal retention test showed stable fluorescence for up to two years when stains were stored appropriately. Finally, complete DNA profiles (100% of alleles) were obtained from all samples (n = 24) after exposure to the reagent and UV light. Because of its ability to enhance semen signal, especially on specific surfaces, and its rapidity of use and detection, STK Spray® may represent a useful aid in the preliminary screening phase.

Humans↗

PubMed2026

The R2R3-MYB transcription factor ScMYB20 negatively regulates drought and salt tolerance through a dual-repression of ScCHALCONE SYNTHASE-1 (ScCHS1)-mediated flavonoid biosynthesis in the desert moss Syntrichia caninervis.

The desert moss Syntrichia caninervis is one of the most desiccation-tolerant land plants known and provides a powerful system for dissecting the molecular foundations of extreme stress adaptation in early-diverging land lineages. The MYB transcription factor superfamily orchestrates secondary metabolism and stress signaling across plants, yet its lineage-specific evolution and mechanistic deployment in bryophytes remain poorly understood. Here, we identified 65 ScMYB genes in the S. caninervis genome and showed that the family expanded predominantly through dispersed duplication, with no detectable synteny to vascular-plant MYBs, indicating bryophyte-specific neo-functionalization. Integrating phylogenetic clustering, cis-element architecture and stress-responsive expression profiling, we pinpointed ScMYB20, a nuclear-localized, S13-subgroup R2R3-MYB that is rapidly and strongly induced by dehydration and salinity. Heterologous overexpression in Arabidopsis, together with overexpression and RNAi in S. caninervis, demonstrated that ScMYB20 negatively regulates drought and salt tolerance by suppressing antioxidant capacity, osmotic adjustment and photosynthetic performance, while concomitantly elevating ROS and MDA accumulation. Mechanistically, ScMYB20 directly binds a TAACCA motif in the ScCHS1 promoter to repress its transcription, and simultaneously sequesters the WD40 protein ScTTG1, a positive transcriptional activator of ScCHS1, thereby antagonising ScTTG1-mediated activation. Transient ScCHS1 overexpression restored flavonoid accumulation, antioxidant capacity and stress tolerance. Together, our findings define a dual-repression module (ScMYB20-ScTTG1-ScCHS1) that fine-tunes flavonoid flux under abiotic stress, and provide evolutionary and mechanistic insights into how R2R3-MYB repressors evolved to balance metabolic investment and stress survival in land plants.

Syntrichia caninervis↗

PubMed2026

Depression and amyloid-β across CSF, PET, and plasma biomarkers: a systematic review and meta-analysis.

Alzheimer's disease is increasingly defined by biomarker evidence of amyloid-β and tau pathology, sharpening questions about whether late-life depression contributes to, or instead reflects, this pathology. We conducted a systematic review and meta-analysis of studies published between 2000 and 2025 that compared amyloid-β biomarkers in adults with and without depression, with depression defined by validated clinical diagnoses or symptom rating scales. Twenty-four studies were included, spanning three biomarker sources: cerebrospinal fluid, positron emission tomography imaging, and plasma. Across all sources, the pooled difference in amyloid-β burden between depressed and non-depressed individuals was small and clustered near zero, indicating only a weak, statistically non-significant tendency toward higher amyloid in depression. When the three sources were examined separately, each yielded a similar near-null result, although between-study heterogeneity was considerable for cerebrospinal fluid and plasma and moderate for imaging. Importantly, a prespecified subgroup analysis showed that imaging results diverged by quantification method: studies using the simpler standardized uptake value ratio clustered around zero, whereas the smaller group of studies using kinetic distribution volume ratio modelling showed a significant positive association, suggesting that methodological choices critically influence the observed relationship. Taken together, these findings indicate that depression is not consistently accompanied by greater amyloid-β burden across widely used biomarker platforms. The distribution volume ratio signal nonetheless raises the possibility of subtle associations that cruder methods may obscure, and suggests that depression may shape Alzheimer's disease trajectories more by modifying the clinical impact of amyloid than by altering its amount.

Humans↗

PubMed2026

Health and Physical Activity Outcomes in Age-Friendly Cities and Communities: A Systematic Review of Emerging Evidence and a Future Research Agenda.

OBJECTIVES: The World Health Organization's (WHO) Global Network of Age-Friendly Cities and Communities (AFCCs) promotes the development of urban environments, policies and services that support the health and participation of older adults. This systematic review examined contemporary evidence concerning associations between WHO AFCC conditions and directly measured health and physical activity outcomes among older residents. METHODS: The registered review adhered to the PRISMA protocol for systematic reviews and meta-analyses and applied the Downs and Black quality criteria for randomised and non-randomised research. RESULTS: Structured Boolean searches of five research repositories identified 17 peer-reviewed studies published between 2017 and 2025 based upon original research conducted in WHO AFCC signatory cities. Although most studies reported positive associations between age-friendly features and domains, such as accessible transport, walkable environments, outdoor infrastructure and self-rated health or physical activity, the strength of evidence was limited by methodological inconsistency, variable study quality and reliance on self-reports. Barriers to evaluation included limited use of longitudinal or quasi-experimental designs, heterogeneous outcome measures, subjective response data and the challenge of establishing appropriate comparison conditions in complex municipal settings. CONCLUSIONS: Strengthening evaluation frameworks for AFCC initiatives is essential for evidence-based urban health policy and governance in rapidly ageing societies. A research agenda is proposed to strengthen AFCC evaluation through standardised measurement, community-based and mixed-methods research, and a greater commitment to co-designed assessment frameworks.

Humans↗

PubMed2026

Temporal evolution of minimally invasive pediatric urolithiasis treatment over 30 years.

Urolithiasis in children has increased substantially over the past 30 years, and surgical management maintains an important role in treatment. Technological advances such as lasers and miniaturization have broadened treatment options, and researchers investigate the best indications for each procedure. The aim was to identify publication trends in the field and explore reasons why Extracorporeal Shockwave Lithotripsy is being gradually less applied in the treatment of pediatric urolithiasis. A Reverse Systematic Review of the literature was conducted regarding the surgical treatment of urolithiasis in children. Five databases were screened, gathering all articles from inception that were evaluated in systematic reviews. We examined 123 publications, 197 reports, and 15,878 procedures, consisting of the largest studied population in the field. There was an increasing number of publications, although in progressively less prestigious journals. The number of studies on miniaturized percutaneous techniques and flexible ureteroscopy has increased closely with the rise in popularity of these procedures worldwide, mainly driven by studies from Asia, Europe, and North America. A trend of self-renewed interest is fueled by technological innovation and has led to fewer publications on Extracorporeal Shockwave Lithotripsy over the years. This review highlights the fact that, despite positive results in recent studies, the low popularity of ESWL within the scientific community is driving a decline in the technique's indications. Moreover, based on the findings of this study, key research priorities include continued reporting of high-quality outcomes, and technological progress in ESWL would contribute meaningfully to the field.

Humans↗

PubMed2026

Effect of Music on Pain, Anxiety, and Satisfaction During Intrauterine Device Application: A Randomized Clinical Trial.

This randomized controlled trial aimed to determine the effect of music played during intrauterine device (IUD) insertion on perceived pain, state anxiety, and satisfaction levels. The study was conducted with 70 women who applied to a maternal and child health and family planning center and were randomly assigned to the intervention and control groups using simple randomization. Data were collected using a Demographic Information Form, the State-Trait Anxiety Inventory (STAI-I), and the Visual Analog Scale (VAS), as well as Bluetooth speakers and the musical piece Evgeny Grinko-Valse. Participants in the intervention group listened to music before and during the IUD insertion procedure, whereas the control group received routine care only. Data were analyzed using SPSS version 26 with appropriate descriptive and inferential statistical methods. Women in the music group had significantly lower perceived pain (p < 0.001) and state anxiety levels during the procedure (p = 0.022), and significantly higher satisfaction levels compared with the control group (p < 0.001). In addition, post-procedure state anxiety levels were positively correlated with pain intensity experienced during and after the procedure (r = 0.542 and r = 0.496, respectively; p < 0.001), and negatively correlated with procedural satisfaction (r = -0.652; p < 0.001). These findings suggest that listening to music during IUD insertion may help reduce pain and anxiety while potentially enhancing patient satisfaction. Trial Registration: NCT06215183.

Humans↗

PubMed2026

Nurse-led acute care post-operative interventions in adult cardiac surgery: a systematic review.

AIMS: The primary aim of this systematic review was to identify nurse-led clinical interventions evaluated in randomized controlled trials (RCTs) for adults who had undergone cardiac surgery. The secondary aim was to assess the effectiveness of these interventions on post-operative clinical and patient-reported outcomes during the acute inpatient phase. METHODS AND RESULTS: A systematic review was undertaken according to an a priori protocol using Joanna Briggs Institute (JBI) methodology and PRISMA guideline for reporting. Eligible studies were RCTs of adult (≥18 years) cardiac surgery, nurse-led inpatient interventions implemented immediately post-surgery and prior to discharge. Six databases were searched from inception to June 2025. Of 2690 records, 19 RCTs were eligible, representing 13 countries, and 3142 participants. Risk of bias varied, with only two low-risk trials. Interventions were grouped into seven domains: behavioural support; temperature management and comfort strategies; pain and symptom management; wound care; infection prevention; respiratory and pulmonary function; and post-operative recovery, mobilization, and hydration. Across these domains, nurse-led interventions were generally feasible, safe, and positively affected patient comfort, physiological stability, symptom relief, and aspects of functional recovery. CONCLUSION: Nurse-led inpatient interventions contribute meaningfully to inpatient post-operative recovery in cardiac surgery, although the broader cardiac surgical nursing scope is underrepresented in RCTs. This review provides a foundation for developing further high-quality research, peer-reviewed interdisciplinary practice guidelines, and strengthening the scope and recognition of cardiac surgical nursing as a distinct specialty. REGISTRATION: PROSPERO-CRD420251063851.

Humans↗

PubMed2026

Systematic modular engineering of genome-integrated Escherichia coli MG1655 for high-level 2'-fucosyllactose production.

2'-Fucosyllactose (2'-FL), the most abundant human milk oligosaccharide (HMO), has attracted considerable interest for its prebiotic and immunomodulatory functions, with broad applications in infant nutrition. In this study, we report the development of a high-yield, genome-integrated 2'-FL-producing strain based on Escherichia coli MG1655 through systematic modular optimization. Starting from a single-copy BKHT strain (MGC06), we first optimized the copy number of the α-1,2-fucosyltransferase (α-1,2-FT) gene BKHT. Subsequently, the GDP-L-fucose supply was enhanced through coordinated genomic integration of the gene clusters cpsG-cpsB and gmd-fcl, while the multidrug efflux transporter gene mdfA was integrated to improve product export and strain robustness. BKHT copy number was then re-evaluated in the optimized background, with four copies yielding the highest production. The final engineered strain, harboring all genetic modifications stably integrated into the chromosome, produced 17.18 g/L 2'-FL in shake-flask culture. In fed-batch fermentation using a 5-L bioreactor, this strain achieved a titer of 154.12 g/L after 60 h, with a productivity of 2.57 g/L/h. Notably, throughout the entire fermentation process, no antibiotics or inducers were supplemented, underscoring the genetic stability and regulatory compliance of this plasmid-free system. To our knowledge, this represents the highest 2'-FL titer reported to date, positioning our engineered strain as a promising candidate for commercial 2'-FL production.

Escherichia coli↗

PubMed2025

Patient Ethnicity and Staff Use of Restraints and Restrictive Practice in Inpatient Psychiatric Services: A Systematic Review.

Restrictive practices such as restraints, seclusion, and forced medication are only intended to be used when the threat is at a level whereby an individual is likely to inflict harm on themselves or another individual. Demographic variations, including ethnicity, may be associated with the use of these practices. However, there is no systematic review on patient ethnicity specifically. The review therefore aimed to establish whether a patient's ethnic identity was associated with staff use of restrictive practices in inpatient psychiatric services. The systematic review followed the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Four databases were searched (PsycINFO, Medline, Embase, and CINAHL). Methodological quality was assessed using the Critical Appraisal Skills Program Checklists. Fifteen studies met the inclusion criteria. A variety of ethnicities were identified within the studies. These were driven by the location of the study. Seclusion (14 studies), forced medication (4), and physical restraint (4) were explored. There were mixed findings, with ethnicity shown to predict restrictive practices in studies having larger participant numbers, longer follow-up periods and less methodological bias. It remains unclear whether ethnicity is a genuinely independent predictor of restraint and coercive practices or interacts with other risk factors. Staff working in inpatient settings should be aware of how unconscious biases might affect clinical practice. Recruiting a diverse workforce from minority ethnic groups into inpatient psychiatric services would be a positive step. However, support for these staff members is important, and all staff should be equipped to respond to ethnic diversity. Future research should explore beyond patient-level factors.

Humans↗

PubMed2026

Association between prenatal exposure to tetrachloroethylene and adverse birth outcomes: Systematic review and meta-analysis.

BACKGROUND: Tetrachloroethylene (PCE) is a ubiquitous chlorinated solvent with documented placental transfer. Despite widespread environmental and occupational exposure, no prior systematic review has synthesized evidence on prenatal PCE exposure and adverse birth outcomes. METHODS: We conducted a systematic review and meta-analysis of observational studies. PubMed, Web of Science, PsycINFO, EMBASE, and CINAHL were searched from inception to July 13, 2026. Eligible studies reported associations between prenatal PCE exposure (drinking water or inhalation) and adverse birth outcomes. Study quality was assessed using the Newcastle-Ottawa Scale (NOS) and Agency for Healthcare Research and Quality (AHRQ) criteria. Random-effects meta-analyses were performed using risk ratios (RRs) with 95% confidence intervals (CIs), with Knapp-Hartung adjustments and Paule-Mandel τ2 estimation. RESULTS: Twenty one studies (1987-2023) met inclusion criteria. Prenatal PCE exposure was associated with spontaneous abortion (8 studies; RR = 1.28, 95% CI 1.00-1.63; I2 = 64.2%). Analyses of stillbirth, central nervous system defects, oral clefts, neural tube defects, preterm birth, low birthweight, and small-for-gestational-age (SGA) yielded positive but statistically non-significant pooled estimates. The certainty of evidence ranged from very low to low across outcomes (GRADE). CONCLUSIONS: Prenatal PCE exposure may be associated with spontaneous abortion, particularly at higher exposure levels, and with SGA. Findings support ongoing regulatory efforts to limit PCE in occupational and environmental settings, particularly for pregnant individuals. Future prospective studies with biological monitoring and confounder-adjusted designs are needed.

Tetrachloroethylene↗

PubMed2026

Associations between multiple essential trace metal concentrations and risk of hyperuricemia: insights from a central Chinese population.

Previous studies have indicated that levels of individual essential trace metals are related to hyperuricemia (HUA), but evidence on their combined effects is limited. To address this gap, the associations of individual and joint levels of 12 essential trace metals (manganese, selenium, nickel, chromium, cobalt, tin, iron, molybdenum, zinc, strontium, vanadium, and copper) with the risk of HUA were investigated in 2,021 adults recruited from Hunan Province, China. Inductively coupled plasma mass spectrometry (ICP-MS) was employed to determine urinary metal concentrations. Logistic regression, Bayesian kernel machine regression (BKMR), and quantile g calculation (Qgcomp) were applied to evaluate the associations of single and mixture metal concentrations with HUA. Of the participants, 516 (25.53%) were diagnosed with HUA. Inverse associations were found between vanadium, chromium, manganese, iron, cobalt, selenium, strontium, and molybdenum levels and HUA, with ORs ranging from 0.63 to 0.91. Conversely, a positive association was observed between zinc concentration and HUA [OR (95% CI): 1.17 (1.01, 1.37)]. Both BKMR and Qgcomp models showed a negative overall effect of essential trace metals on HUA risk, with strontium (- 43.6%) and vanadium (- 27.8%) being the main contributors. In addition, formal interaction tests revealed significant effect modification by age for tin and by BMI for zinc. In conclusion, the levels of essential trace metals were linked to a decreased risk of HUA, and these associations were modified by age and BMI only for specific metals.

Humans↗

PubMed2026

Culture of infectious human norovirus isolated from live contaminated oysters.

Human noroviruses are a major cause of foodborne outbreaks worldwide. Filter-feeding shellfish, such as oysters, can bioaccumulate these viruses in their digestive tissue when grown in sewage-impacted coastal areas and are often implicated in norovirus foodborne outbreaks. Despite the high sensitivity of current molecular assays, these methods for norovirus detection in shellfish fail to distinguish between infectious and non-infectious particles. Assessing norovirus infectivity in shellfish remains a challenge due to the lack of suitable isolation methods that maintain capsid integrity. In this study, a protocol for isolating infectious norovirus from oyster tissues, based on chloroform-butanol elution and polyethylene glycol concentration (CB-PEG), was optimized for the recovery of human norovirus GI and GII. While CB-PEG method recovered various norovirus GI and GII genotypes, it was less efficient at the genomic level than a protocol based on proteinase K elution (adapted from ISO 15216) and showed genotype-dependent viral recovery rates. By optimizing the flocculation step, we improved the method's compatibility with human intestinal enteroid (HIE) cultures. Using this approach, we successfully quantified infectious norovirus GII.3 titers recovered from artificially-contaminated live oysters. Interestingly, infectious virus was better isolated following a freezing step of the digestive tissues, with titers ranging from 13 to 40 TCID50/mL for positive samples. In conclusion, this study established an optimized methodological approach for the relative quantification of infectious norovirus GII.3 in shellfish, paving the way for future research on viral persistence and inactivation strategies in this foodstuff.

Norovirus↗

PubMed2026

Sea urchin co-culture boosts abalone growth by reducing environmental stress and remodeling gut microbiota.

Biofouling and microenvironmental deterioration are major bottlenecks restricting the intensive aquaculture of Pacific abalone (Haliotis discus hannai). While co-culturing offers an eco-friendly mitigation strategy, the underlying mechanisms promoting abalone growth remain poorly understood. This study evaluated the growth performance of H. d. hannai co-cultured with varying densities of the sea urchin (Strongylocentrotus intermedius). By employing transcriptome and 16S rRNA sequencing of the abalone gut, we investigated the synergistic responses of host gene expression and gut microbiota. Compared with the monoculture group, the co-culture groups showed significantly less biofouling and greater growth of abalone, with the co-culture (n = 15) exhibiting the best outcomes. Transcriptomic analysis revealed 1444, 760, and 508 DEGs in G5, G10, and G15, respectively, compared with G0. These DEGs were significantly enriched in metabolic pathways, including glycolysis and sterol metabolism, indicating a shift in intestinal energy metabolism from stress defense toward growth under co-culture conditions. Gut microbiota profiling identified Proteobacteria and Firmicutes as the dominant phyla, with specific functional taxa (e.g., Psychrilyobacter and Akkermansia) enriched in a density-dependent manner. Furthermore, correlation analysis demonstrated that growth traits positively correlated with growth-promoting taxa (e.g., the unclassified AB1 lineage), but negatively correlated with potentially opportunistic taxa (e.g., Tabrizicola). These findings provide insights into a potential synergistic mechanism of "environmental stress alleviation-metabolic reprogramming-microecological remodeling" driving abalone growth, providing a theoretical foundation for optimizing co-culture systems and developing growth-associated biomarkers.

Animals↗

PubMed2026

Meaning in Life in Palliative Cancer Care: Psychosocial and Existential Outcomes-A Systematic Review.

BackgroundExistential distress, marked by hopelessness, loss of meaning, and spiritual suffering, is prevalent among patients with advanced illness, and is associated with psychological burden and a wish to hasten death (WTHD).PurposeThis systematic review aimed to synthesize current evidence on meaning in life (MIL) in adult palliative care (PC) populations, focusing on its associations with quality of life (QOL), mental health, existential and spiritual well-being (SWB), and WTHD.MethodsMEDLINE, Web of Science, Scopus, and the Cochrane Library were searched for eligible studies (English, 2016-2024) involving adult cancer patients receiving PC. MIL was examined as a central intervention component or outcome. Risk of bias was assessed: findings were synthesized narratively. The review was registered in PROSPERO.ResultsEight studies (n = 1733 participants) were included: four cross-sectional, two randomized controlled trials, one longitudinal observational study, and one qualitative study. Several studies had small samples and substantial attrition. Risk of bias was high (n = 7), and moderate in one cross-sectional study. MIL was inversely associated with depression, anxiety, demoralization, and WTHD; and positively associated with QOL and SWB. MIL may also mediate psychological outcomes (eg, purpose, coherence, and personal values). However, heterogeneity in MIL conceptualization and measurement, combined with low methodological quality, limited comparability and certainty of findings.ConclusionMIL may be relevant to psychosocial/existential outcomes in PC. Conclusions are constrained by a small and methodologically weak evidence base. Further high-quality, longitudinal research is needed before MIL-centered interventions can be recommended for routine clinical practice.

Humans↗

PubMed2026

Strategy for enhanced production of A40926B0 in Nonomuraea gerenzanensis using an efficient CRISPR/AsCas12f1 system.

The global emergence of vancomycin-resistant Gram-positive pathogens underscores the urgent need for efficient production of novel lipoglycopeptide antibiotics. Dalbavancin, a last-resort therapeutic agent, relies on its key biosynthetic precursor A40926B0, whose industrial manufacture is severely limited by the low yield of wild-type Nonomuraea gerenzanensis and inefficient genetic tools for this rare actinomycete. Here, we developed a high-efficiency CRISPR/AsCas12f1 genome editing system and applied systematic metabolic engineering to boost A40926B0 biosynthesis. First, conjugation conditions were optimized to elevate the transfer efficiency in N. gerenzanensis D11. The hypercompact AsCas12f1 nuclease showed markedly lower cytotoxicity than SpCas9 and enabled 100% gene deletion efficiency with preferred PAMs (TTTG, CTTG, GTTG). Second, we strengthened the shikimate pathway via multiple genetic strategies: overexpressing feedback-resistant DAHP synthase (aroG fbr ) and chorismate mutase/prephenate dehydrogenase (tyrA fbr ), as well as knocking out pheA. This manipulation blocks the phenylalanine synthetic branch and redirects metabolic flux toward the l-tyrosine branch. Third, we engineered the branched-chain fatty acid (BCFA) pathway via promoter replacement of bkdA2B2C2, LipAB, fabF and deletion of acdH to enhance isododecanoyl side-chain supply. The combinatorial engineering yielded strain B-13, which produced 1740 mg/L A40926B0 in shake flasks. Finally, 50-L fed-batch fermentation with continuous maltodextrin feeding further increased the titer to 1817 mg/L, the highest reported titer to date. This work establishes a robust CRISPR editing tool for N. gerenzanensis and provides valuable engineering references for precursor-oriented strain improvement targeting lipoglycopeptide antibiotics, offering insights for the industrial scale production of A40926B0.

A40926B0↗

PubMed2026

Metabolic depot for nucleated erythrocyte degradation: molecular and structural elucidation of the teleost melanomacrophage center.

The function of melanomacrophage centers (MMCs) has long been controversial. While their foundational function is widely accepted as "metabolic dumps" for waste processing, a widely circulated hypothesis posits that they are primitive germinal centers (GCs) executing adaptive immunity. To elucidate this controversy, this study systematically evaluated the splenic MMCs in a higher teleost ( Micropterus salmoides) by combining transmission electron microscopy (TEM) and high-resolution spatial transcriptomics. Structurally, TEM revealed that the MMC comprises a core with characteristic sparse cellular density, filled with cellular debris and encapsulated by a fibrous layer. Molecularly, under physiological conditions, MMC regions exhibited low transcriptional activity. We did not detect clear enrichment of B cell and T cell lineage genes, and the key GC marker aicda was not observed. Conversely, its predominant molecular signature was characterized by macrophage-driven iron metabolism (e.g., ferritin) and erythrocyte degradation (e.g., hba1). Furthermore, the physicochemical properties of MMCs pigments (e.g., argyrophilia) suggest that traditional histological staining methods warrant cautious interpretation regarding potential non-specific signals. In conclusion, our findings characterize the MMC as a highly specialized metabolic processing and sequestration niche. This study provides new perspectives on the evolution of immune-metabolic homeostasis in poikilothermic vertebrates, advances comparative immunology, and offers a critical scientific reference for the accurate interpretation of MMCs as a biological indicator in pathology and ecotoxicology.

Animals↗

PubMed2026

Unveiling the molecular basis of gonadal development: Multi-omics uncovers sex-related genes and steroid pathways in Sinonovacula constricta.

The razor clam Sinonovacula constricta is an economically important cultured mollusk in China, but the molecular mechanism of its gonadal development and sexual differentiation remains unclear. This study integrated gonadal transcriptomic, proteomic, and metabolomic analysis to identify key sex-related molecules. Transcriptome analysis identified 2795 DELs and 6497 DEGs between sexes, including the sex-related genes Fem-1b, Fem-1c, GUCY1B2 and FAT4, as well as a regulatory network of 39 lncRNA-mRNA pairs involving Tektin-4, Ropporin-1, Histone H1, and FoxN4. Proteomic analysis revealed 3217 DEPs: Tektin family members, Ropporin-1 and Tssk proteins were upregulated in the testis, while histone H1 and FAT4 were upregulated in the ovary. Metabolomic analysis detected 409 DEMs, with uridine identified as a potential sex differential marker (upregulated in the ovary), and 23 gonadal development-related DEMs showed sex-specific upregulation. Integrative transcriptome-proteome analysis identified 1543 co-expressed DEGs/DEPs enriched in nucleosome assembly, oxidative phosphorylation, and carbon metabolism, including key sex-related genes AKAP14, Tektin/Tssk families, Histone H1, and FAT4. Transcriptome-metabolome integration identified 32 shared KEGG pathways (e.g., biosynthesis of unsaturated fatty acids, pyrimidine metabolism), while proteome-metabolome integration revealed 5 (positive ion) and 6 (negative ion) co-enriched pathways, with alanine, aspartate and glutamate metabolism and oxidative phosphorylation being functionally relevant to gonadal development. Collectively, these results reveal the molecular basis of gonadal development, highlight critical sex-related genes and steroid metabolic pathways, and provide valuable resources for future reproduction and breeding in S. constricta.

Animals↗