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PubMed2026

Long-term microbiome and clinical effects of a microbiome-guided personalized diet versus low-FODMAP diet in irritable bowel syndrome: A 12-month follow-up randomized controlled trial.

Dietary therapy is central to irritable bowel syndrome (IBS) management, yet the long-term durability of the low-FODMAP diet (LFD), and of microbiome-guided personalization, remains unclear. We assessed the long-term clinical and gut-microbiome effects of a microbiome-guided personalized diet (PD) compared with a standard LFD in adults meeting Rome IV criteria for IBS. In this multicenter, open-label randomized controlled trial with blinded outcome assessment, participants who completed a 6-week dietary intervention (PD or LFD) were followed at 6 and 12 months without further dietary intervention. Outcomes included the IBS Severity Scoring System (IBS-SSS), IBS Quality of Life (IBS-QOL), and the Hospital Anxiety and Depression Scale (HADS); gut microbiota were profiled by 16S rRNA sequencing. Longitudinal changes were evaluated using linear mixed-effects models, responder analyses, PERMANOVA, and PERMDISP. Both diets reduced IBS-SSS at 6 weeks. PD maintained symptom improvement at 6 and 12 months (-82.0 and -78.3 points from baseline), whereas LFD benefits regressed by 12 months (+29.3 points; between-group p = 0.001). At 12 months, IBS-SSS responder rates were higher with PD than LFD (62.5% vs 34.5%; absolute risk difference +28.0%, 95% CI 4.2-47.7; Fisher p = 0.029), and IBS-QOL, HADS-anxiety, and HADS-depression showed more favourable trajectories with PD. PD was associated with sustained Shannon alpha-diversity gains (+0.488 at 6 weeks; +0.205 at 12 months; both p < 0.01). A modest between-group beta-diversity difference at 6 months (R2 = 0.035; p = 0.011) was not significant at 12 months. This hypothesis-generating follow-up suggests more durable benefit with PD; larger trials powered for long-term clinical and microbiome outcomes are warranted.

Humans↗

PubMed2026

A host-encoded prophage targets a Candidate Phyla Radiation bacterium and shapes episymbiotic interactions.

The Patescibacteriota, also known as the Candidate Phyla Radiation (CPR), represent a large lineage of ultrasmall bacteria with highly reduced genomes and obligate dependence on bacterial hosts. Although genomic analyses have revealed CRISPR-Cas and restriction-modification systems in many CPR genomes, no cognate bacteriophages (phages) have been isolated, leaving CPR-phage interactions unexplored. Nanosynbacter lyticus TM7x, the first cultivated CPR bacterium, grows episymbiotically on its host, Schaalia odontolytica XH001, in the human oral microbiome. Here, we identify Xhp1, an inducible prophage of XH001 that is preferentially activated during episymbiosis with TM7x. Released Xhp1 particles infect prophage-free XH001 via distinct strategies determined by host growth mode, establishing lysogeny under planktonic conditions but driving lytic infection during surface-associated growth. Xhp1 also binds efficiently to TM7x and exhibits limited infection under the conditions tested, indicating direct phage-CPR interactions. Importantly, TM7x modulates Xhp1 availability in a spatially dependent manner. In planktonic culture, free-floating TM7x reduces lysogenic conversion of XH001ΔXhp1, consistent with TM7x acting as a phage sink that lowers effective phage concentration. In contrast, during surface-associated growth, TM7x increases XH001ΔXhp1 susceptibility to lytic infection, likely by locally concentrating phage particles within a constrained niche. These results demonstrate that CPR bacteria can regulate viral encounter rates through spatial organization. In spatially structured environments such as oral biofilms, such modulation may shape infection dynamics and community structure. Together, this work characterizes the first CPR-targeting phage and reveals a an important role for phages in CPR-host bacteria interactions.

Prophages↗

PubMed2026

Recovering membrane interaction kinetics of single molecules from 3D tracking data.

Interactions between cytosolic biomolecules and the bacterial inner membrane are fundamental to many cellular processes, yet directly measuring their binding kinetics in living cells remains challenging. Conventional 2D single-molecule tracking analyses can be insufficient, particularly when membrane association does not markedly alter the diffusion rate. Here, we present a method to recover membrane interaction kinetics from 3D single-molecule trajectories in rod-shaped bacteria. Using simulated 3D tracking data, we identify membrane-associated motion by quantifying how well short trajectory segments follow the circular curvature of the cell membrane. The resulting measure is further analyzed using a hidden Markov modeling framework, enabling robust discrimination between cytosolic and membrane-bound states and capturing the dynamics of state transitions without requiring diffusion-rate changes or direct colocalization with membrane markers. This work establishes a general framework for extracting membrane interaction kinetics from 3D single-molecule tracking data in live bacteria and highlights the value of realistic microscopy simulations for quantitative interpretation and systematic bias assessment.

Kinetics↗

PubMed2026

Metal-organic frameworks nanozyme-integrated portable microneedle patch for visual bacterial monitoring in meat.

Foodborne microbial contamination is a major global health concern, with conventional methods often being time-consuming and complex. Herein, we developed a novel portable biosensor by integrating microneedle patch technology and a metal-organic framework (Fe/Cu-NBDC MOF) nanozyme, enabling rapid, on-site, visual detection of bacteria in meat. The sensing system works by encapsulating aptamer-functionalized MOF nanozymes within a hydrogel patch, where their catalytic sites are initially blocked by the aptamer. In the presence of Staphylococcus aureus (S. aureus) as the target, the specific aptamer's binding to bacteria exposes numerous catalytic sites, further activating the chromogenic reaction of the tetramethylbenzidine‑hydrogen peroxide (TMB-H₂O₂) system, enabling visual detection of S. aureus. The biosensor demonstrates a detection limit of 82 CFU/mL with excellent specificity to successfully apply to commercial mutton. By integrating sampling, enrichment, and visual detection into a single compact device, this platform offers a practical, efficient solution for rapid on-site screening of foodborne pathogens.

Biosensing Techniques↗

PubMed2026

Single-cell transcriptomics reveals heterogeneous stress responses and Mg2+-mediated survival mechanisms in Lactobacillus delbrueckii subsp. bulgaricus during freeze-drying and storage.

Maintaining the viability of lactic acid bacteria during dehydration and subsequent storage remains a significant challenge. Here, we employed single-cell RNA sequencing to reveal the heterogeneous stress responses of Lactobacillus delbrueckii subsp. bulgaricus, identifying seven distinct transcriptional clusters across the liquid culture, freeze-drying, and storage phases. The dominant clusters in the freeze-drying and storage were not completely consistent, showing significant functional differentiation. Genomic stability may be important for survival during freeze-drying and storage, while intracellular energy homeostasis appears important for viability during storage. The magnesium transporter mgtB was highly expressed in clusters tolerant to freeze-drying and storage, suggesting a critical role for Mg2+ homeostasis. Further experimental validation confirmed that Mg2+ treatment significantly bolstered stress resistance, increasing immediate post-freeze-drying survival by over 2-fold (up to 92.90%) and post-storage survival by over 5-fold (up to 5.98%). Proteomic data indicated that Mg2+ supplementation correlated with the maintenance of several biological functions potentially relevant to bacterial survival during freeze-drying and storage, including DNA repair, translation, and central carbon metabolism. These findings provide a map of microbial stress resistance through population heterogeneity and offer a potential strategy that may be adapted for enhancing the stability of other industrial lactic acid bacteria products.

Freeze Drying↗

PubMed2026

Acetylcholine signaling regulates osmotic stress adaptation in the phytopathogen Dickeya solani.

Plants impose strong selective pressures that shape both the composition and functional potential of plant microbiomes. The adaptation of plant-associated bacteria to their hosts relies on an extensive repertoire of signal transduction systems that sense plant-derived molecules and dynamically adjust bacterial physiology and metabolism within the holobiont. These signals include key plant signaling compounds that regulate processes essential for plant-microbe interactions. Among them, acetylcholine is emerging as an important signaling molecule in both plants and bacteria. Here, we demonstrate that acetylcholine regulates the expression of the osmotic stress response betIBA gene cluster in the important phytopathogen Dickeya solani, where it plays an important role in osmoprotection. We show that the TetR-family transcriptional regulator associated with this pathway, BetIDs, recognizes acetylcholine as well as choline and trimethylamine. These three ligands differentially induce betIBA transcription in a manner that correlates with their binding affinities. Ligand binding does not affect BetIDs binding to the bet promoter or its oligomeric state. Instead, it induces pronounced changes in the secondary structure of BetIDs, with the magnitude of these conformational changes being ligand-dependent. We further show that quorum sensing modulates osmotic stress tolerance in D. solani by regulating the expression of the Bet pathway. The Bet system is required for the full virulence of D. solani, particularly in chemically complex plant tissues. Phylogenetic analyses reveal that the BetIBA system is widely distributed among plant-associated Pseudomonadota, collectively supporting its importance for bacterial survival and adaptation in plant-related environments.

Osmotic Pressure↗

PubMed2026

A novel urease-producing strain effectively induces cadmium biomineralization under low-temperature stress.

Microbially induced carbonate precipitation (MICP) has been widely used to immobilize Cadmium (Cd) in contaminated soils in mining-affected regions. However, its remediation efficacy under low-temperature stress, as well as the nucleation process that regulates Cd biomineralization via carbonate precipitation by psychrophilic bacteria, has yet to be investigated. Here, we isolated Pseudomonas sp. J-6, a novel urease-producing strain from tailings in high-altitude cold regions, exhibiting unparalleled cold adaptability at 5 °C and achieving 95.85 % Cd removal efficiency by MICP at 10 °C. Furthermore, the coprecipitation process of Ca1-xCdxCO3 was clarified through the continuous observation of the precipitates after the low-temperature MICP reaction. The crystal morphology transitioned from loose vaterite in the early stage to a dense square-block morphology in the middle stage. Cd2+ progressively shifted from a surface-bound state to lattice incorporation, ultimately resulting in the formation of stable Cd-substituted calcite crystals. In this process, low temperatures led to the formation of larger, highly ordered Cd-substituted calcite crystals, thereby strengthening Cd sequestration and its long-term stability. In addition, under low-temperature stress, Pseudomonas sp. J-6 induced MICP reaction decreased the bioavailable Cd in alpine slag soil by 44.85 % and enhanced physical properties. In the freeze-thaw cycles, the remediation efficiency remained stable. This study clarified the biomineralization potential in high-altitude cryogenic environments and the nucleation process of Cd biomineralization by psychrophilic bacteria-induced carbonate precipitation, filling a critical research gap in its application under extreme conditions and highlighting its promise for sustainable remediation of heavy metal pollution under low-temperature stress.

Cadmium↗

PubMed2026

The role of media in reducing and reinforcing stigma: A randomized controlled trial investigating the impact of positive and negative representations of visible difference.

OBJECTIVES: Individuals with visible differences often experience appearance-related stigma and discrimination, reinforced by negative media portrayals. In contrast, positive portrayals may challenge stereotypes and promote acceptance. This study examined whether exposure to positive, negative or neutral images of visible difference influences appearance-related stigma, body appreciation and broad conceptualizations of beauty. It was hypothesized that positive images would decrease stigma and increase body appreciation and broad conceptualizations of beauty, whereas negative images would increase stigma and reduce broad conceptualizations of beauty. DESIGN: An online randomized controlled experiment using a mixed repeated-measures design compared three conditions (positive, negative, neutral) across pre- and post-exposure. METHODS: A sample of 103 adults viewed 10 images of individuals with visible differences presented in one of three conditions: positive (positive captions), negative (villains with visible differences and negative captions) or neutral (without captions). Participants completed pre- and post-measures of appearance-related stigma, body appreciation and broad conceptualizations of beauty. Repeated-measures ANOVAs examined within- and between-group changes. RESULTS: Appearance-related stigma significantly increased in the negative condition, while remaining unchanged in the positive and neutral groups. Body appreciation significantly increased from pre- to post- across all conditions. No significant effects emerged for broad conceptualizations of beauty. CONCLUSIONS: Negative portrayals of visible difference may reinforce stigma, highlighting the need to discourage such depictions in media. While positive exposure did not significantly reduce stigma, viewing images of visible difference increased observers' body appreciation, indicating potential downward social comparison. Future research should explore strategies to strengthen stigma reduction and broaden conceptualizations of beauty.

Humans↗

PubMed2026

Novel Germline ELP1 Splice-Acceptor Variant in NF1-Negative Optic Pathway Glioma: Expanding the Clinical Spectrum Associated With ELP1 Variation.

We report a 7-year-old boy with NF1-negative optic pathway glioma harboring a novel germline ELP1 splice-acceptor variant (NM_003640.5:c.2205-2A>G) identified by whole-exome sequencing. The variant was likely pathogenic (ACMG/AMP: PVS1, PM2) and inherited from an asymptomatic father, consistent with incomplete penetrance, expanding the limited evidence linking germline ELP1 variation to gliomas.

Humans↗

PubMed2026

Targeting TP53 in triple-negative breast cancer: Molecular pathogenesis, therapeutic implications, and emerging pharmacological strategies.

Triple-negative breast cancer (TNBC) remains a highly aggressive and therapeutically challenging subtype, defined by the absence of oestrogen, progesterone, and HER2 expression. Tumour Protein 53 (TP53) mutations represent the most frequent genetic alteration, occurring in over 80% of cases and driving tumour initiation, progression, and therapeutic resistance. Mutant p53 proteins not only lose canonical tumour-suppressive functions but also often acquire gain-of-function (GOF) oncogenic properties that promote metastasis, genomic instability, and resistance to mechanisms like ferroptosis. This review examines the biological role of TP53 in TNBC pathogenesis and evaluates emerging pharmacological strategies aimed at targeting these vulnerabilities. Key approaches include the pharmacological reactivation of mutant p53 using small molecules such as APR-246, COTI-2, and the mutation-specific reactivator rezatapopt (PC14586), which has shown significant clinical tumour reduction in Y220C-mutant patients. Other strategies involve targeted protein degradation, the exploitation of synthetic lethal interactions (e.g., Chk1 or Aurora kinase B inhibition), and the use of natural products like cryptolepine or piperine derivatives. Recent clinical evidence further highlights the potential of combining epigenetic agents like decitabine with chemotherapy in TP53-mutant populations. Integrating TP53 mutation status into biomarker-driven treatment paradigms is a pivotal step toward achieving precision oncology and improving clinical outcomes for patients with TNBC.

Precision oncology↗

PubMed2026

Frontline therapies for adult patients with newly diagnosed Philadelphia chromosome-negative B-cell acute lymphoblastic leukemia: a systematic literature review.

OBJECTIVES: Philadelphia (Ph) chromosome-negative B-cell acute lymphoblastic leukemia (B-ALL) is the most common ALL in adults. Overall survival (OS) with frontline chemotherapy remains poor. Blinatumomab is currently the only targeted agent approved for frontline treatment. METHODS: We systematically reviewed 96 studies (43 interventional, 53 observational) between 2012-2026 evaluating frontline pharmacologic therapy in adults with Ph- B-ALL. RESULTS: Across chemotherapy studies, nearly half of patients relapsed within 3 years, and only 49%-69% survived beyond 3 years. Blinatumomab demonstrated robust and consistent efficacy in first complete response (CR1), supported by 2 randomized controlled trials (RCT) and 16 single-arm trials (SAT). In one RCT, blinatumomab reduced the risk of death by 59% versus chemotherapy alone (HR 0.41) when added to frontline consolidation in minimal residual disease (MRD) negative patients. Median OS reached 41.2 months in a SAT where blinatumomab monotherapy was administered to patients in MRD-positive CR1. SATs showed consistent efficacy outcomes regardless of age, MRD status, or chemotherapy backbone. DISCUSSION: Additional targeted therapies still under investigation have shown mixed results. CONCLUSION: Frontline inotuzumab (±blinatumomab) plus chemotherapy showed promise in older populations, while the efficacy benefit of rituximab was inconclusive. No new safety signals were identified in the frontline setting for targeted therapies.

Humans↗

PubMed2026

De-escalation of radiotherapy in HPV-negative non-nasopharyngeal head and neck squamous cell carcinoma: a systematic review.

BACKGROUND: Definitive and postoperative radiotherapy are central components of treatment for head and neck squamous cell carcinoma (HNSCC) but are associated with significant toxicities that can impair long-term function and quality of life. De-escalation strategies, aiming to reduce treatment-related morbidity while maintaining tumor control, have attracted increasing interest. However, most research has focused on HPV-positive oropharyngeal carcinoma. Systematic evidence for HPV-negative disease remains limited. METHODS: PubMed and EMBASE were searched for prospective studies investigating radio(chemo)therapy de-escalation in HPV-negative, HPV-unspecified, or mixed non-nasopharyngeal HNSCC populations. CLINICALTRIALS: gov was searched for ongoing prospective trials. Data extraction and verification were performed independently by three investigators. RESULTS: Screening of 3156 records identified 14 published prospective studies, 10 in the definitive and four in the postoperative setting. Strategies included reduction or omission of elective nodal volumes, dose reduction, and combined approaches. Additionally, 23 ongoing prospective trials were identified. Across studies, elective nodal failure rates were consistently low (0-4.6%), with most recurrences occurring within high-dose volumes rather than de-escalated elective regions. Randomized evidence for elective nodal dose reduction is mixed: two trials maintained regional control and reduced acute toxicity, whereas another was stopped for futility. CONCLUSION: Available evidence on de-escalation in HPV-negative HNSCC is limited, derived primarily from small, heterogeneous phase II studies with mixed HPV populations. Although data are promising in selected settings, notably for elective nodal control, the randomized evidence for elective nodal dose reduction is conflicting, and further adequately designed prospective randomized trials are required.

Humans↗

PubMed2026

PGR expression as a pharmacogenomic companion biomarker to GENE70-derived genomic risk in ER-positive/HER2-negative breast cancer.

BACKGROUND: The biology of the estrogen receptor-positive (ER+) and human epidermal growth factor receptor 2-negative (HER2-) breast cancers is heterogeneous even when they are categorized by their risk via genomics. Transcriptomic PGR expression reflects endocrine pathway activity and may provide complementary biological information within established GENE70-derived genomic-risk categories. Whether this molecular marker improves the biological interpretation of genomic-risk stratification beyond conventional clinicopathological assessment remains uncertain. OBJECTIVES: The aim of this study was to determine whether transcriptomic PGR expression provides complementary biological and prognostic information within reconstructed GENE70-derived genomic-risk categories and refines the characterization of endocrine-related tumour biology in ER-positive/HER2-negative breast cancer. METHODS: This study analysed publicly available transcriptomic and clinical data from three cohorts: METABRIC (discovery cohort), GSE96058/SCAN-B cohort (validation cohort) and TCGA-BRCA cohort (molecular validation cohort). The GENE70-derived genomic-risk score was reconstructed for each cohort using matched genes. Cox regression, Kaplan-Meier analysis and subgroup comparisons were used to assess relationships between PGR expression, clinicopathologic variables, molecular features and survival outcomes. RESULTS: Across the three independent cohorts, low transcriptomic PGR expression was consistently associated with higher GENE70-derived genomic risk, increased MKI67 expression, reduced ESR1 expression and enrichment of the Luminal B subtype. Survival findings differed between cohorts. In the discovery METABRIC cohort, transcriptomic PGR expression showed heterogeneous associations with survival, particularly within GENE70-derived high-risk subgroups, whereas the external GSE96058/SCAN-B validation cohort demonstrated consistent associations between low PGR expression and poorer overall survival in both the overall ER-positive/HER2-negative population and GENE70-derived high-risk subgroups. CONCLUSION: These findings suggest that transcriptomic PGR provides complementary biological and prognostic information within GENE70-derived genomic-risk categories. However, because treatment response was not evaluated in the present study, the findings should not be interpreted as evidence of predictive or pharmacogenomic utility and prospective studies incorporating treatment-response analyses are required before such applications can be established.

Humans↗

PubMed2026

Molecular evaluation of residual disease following neoadjuvant chemotherapy in triple-negative breast cancer CALGB 40603 (Alliance).

BACKGROUNDDespite therapeutic advances in early-stage triple-negative breast cancer (TNBC), residual disease (RD) following neoadjuvant therapy remains a key predictor of a worse prognosis and obstacle to improving patient outcomes.METHODSTo better characterize RD and identify survival-associated features, we performed comprehensive transcriptomic profiling of 340 pretreatment stage II/III TNBCs and 70 matched posttreatment RD samples from the randomized CALGB 40603 (Alliance) phase II clinical trial. To explore preclinical treatment strategies for RD, patient-derived xenograft (PDX) mouse models mimicking RD were treated with antibody-drug conjugates (ADCs).RESULTSOur study shows prognostic genomic features measured pretreatment may differ from prognostic features measured posttreatment from RD specimens. Patients with a genomic PAM50 subtype of basal-like in RD specimens had a poor survival outcome, and their matching pretreatment tumors were characterized by elevated chromosomal amplifications of oncogenic drivers and significantly reduced B and T cell expression features. Paired analyses of basal-like RD and matched pretreatment tumors revealed further lymphocyte depletion in RD, along with lower expression of MHC class I and interferon signaling, indicating an immune-cold RD microenvironment. Treatment of a basal-like and conventional chemotherapy-resistant PDX model, resembling basal-like RD, with sacituzumab govitecan or trastuzumab deruxtecan produced a marked antitumor response.CONCLUSIONRD biology differs from pretreatment tumors, with basal-like subtype RD following neoadjuvant chemotherapy being immune cold and associated with poor survival. Preclinical modeling suggests this high-risk group may benefit from adjuvant ADC therapy.TRIAL REGISTRATIONClinicalTrials.gov NCT00861705.FUNDINGNIH NCI U10CA180821 (Alliance for Clinical Trials in Oncology), NCI U24CA176171 (Alliance for Clinical Trials in Oncology), NCI UG1CA233373 (Alliance for Clinical Trials in Oncology), NCI Breast SPORE program P50-CA058223; Susan G. Komen SAC-160074; Breast Cancer Research Foundation BCRF-23-127; NIH NCI R01-CA229409; UNC LCCC Triple Negative Breast Cancer Center.

Humans↗

PubMed2026

Effects of sub-anesthetic doses of esketamine on immune function and postoperative negative emotions in acoustic neuroma patients: a randomized clinical trial.

BACKGROUND: Patients undergoing acoustic neuroma (AN) surgery often experience postoperative negative emotions, including anxiety, depression, and immune function suppression. This trial evaluated whether perioperative sub-anesthetic esketamine improves early postoperative negative emotions and immune function. METHODS: In this single-center, double-blind, randomized trial, 84 patients scheduled for AN surgery were assigned to esketamine (n = 42) or placebo (n = 42). The esketamine cohort received a continuous intravenous infusion of esketamine at 0.2 mg·kg-1·h-1 during anesthesia, followed by 1 mg·kg-1 esketamine as an adjuvant in patient-controlled intravenous analgesia (PCIA). The placebo group received saline. The primary outcome was the incidence of depression on postoperative day (POD1), defined as a Hospital Anxiety and Depression Scale-Depression subscale (HADS-D) score > 7. RESULTS: Seventy-seven patients completed the study (39 in the esketamine group, 38 in the placebo group). Esketamine significantly reduced the incidence of depression at POD1 (7.7% versus 31.6%; relative risk 0.24, 95% CI: 0.08-0.80, p = 0.008) and POD3 (0.0% versus 15.8%, relative risk 0.00, 95% CI: 0.00-0.47, p = 0.031) compared with placebo. The incidences of anxiety on POD1 and 3 and sleep disturbances on POD1 were also significantly reduced (p < 0.05). Notably, no significant differences were observed between the two groups in terms of immune function, postoperative pain scores, or intraoperative morphine equivalent. Adverse events did not differ between the groups. CONCLUSION: Perioperative sub-anesthetic esketamine reduced postoperative depression and anxiety, and improve sleep quality after AN surgery, without significant effects on early immune function or acute postoperative analgesia. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2400084537.

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

The association of 25-hydroxyvitamin D deficiency with neuroinflammation and prognosis in HIV-negative cryptococcal meningitis.

BACKGROUND: Cryptococcal meningitis (CM) in HIV-negative individuals is increasing, yet the role of vitamin D remains unclear. This study investigates serum 25-hydroxyvitamin D [25(OH)D] levels and their clinical implications in HIV-negative CM patients. METHODS: We conducted a retrospective case-control study of 93 HIV-negative CM patients and 191 healthy controls (HCs). Serum 25(OH)D levels, cerebrospinal fluid (CSF) fungal burden, cytokine profiles, the incidence of postinfectious inflammatory response syndrome (PIIRS), and one-year mortality were assessed. Bivariate logistic regression models identified predictors of mortality. RESULTS: CM patients had significantly lower serum 25(OH)D levels than HCs (18.33 vs. 23.69 ng/mL, p < 0.001), with a higher rate of deficiency (<20 ng/mL) in the CM group (59.14% vs. 34.03%, p < 0.001). Lower 25(OH)D levels were associated with elevated CSF levels of IL-6 and IL-8 (p < 0.05). Deficiency was linked to increased PIIRS incidence (43.64% vs. 21.05%, p = 0.028). Bivariate logistic regression showed a protective trend for 25(OH)D levels (OR 0.939, 95% CI 0.877-1.006, p = 0.075), although deficiency was not associated with higher mortality. CONCLUSIONS: Serum 25(OH)D deficiency is prevalent in HIV-negative CM patients and linked to neuroinflammation and increased risk of PIIRS. Serum 25(OH)D levels may serve as a useful prognostic marker, although further research is needed.

Humans↗

PubMed2026

Flexible ureteroscopy with a flexible and negative suction ureteral access sheath versus traditional sheath for treatment of infectious upper urinary tract stones: A prospective, randomized controlled study.

To evaluate the efficacy and safety of the flexible ureteroscopy (fURS) with a flexible and negative suction ureteral access sheath (FANS) versus traditional sheath for patients with infectious upper urinary tract stones (IUUTS). A total of 185 patients were enrolled, with 93 assigned to the FANS group and 92 to the traditional UAS group. The primary outcome was the stone-free rate (SFR) at the first postoperative day. Secondary outcomes included the SFR at 30 days postoperatively, operative time, hemoglobin reduction, length of hospital stay, quality of life (QoL) improvement, incidence of ureteral stricture at 3 months, and surgery-related complications. No significant differences were observed between the two groups in baseline demographics or preoperative clinical characteristics (P > 0.05). The FANS group had significantly lower white blood cell count, C-reactive protein, and procalcitonin levels at 6 and 24 h postoperatively (all P < 0.05). Mean operative time was significantly shorter (P < 0.001), QoL improvement was obviously greater (P < 0.001), and average hospital stay was shorter in the FANS group (P < 0.001). The SFRs on postoperative day 1 and at 30 days were both significantly higher in the FANS group (both P < 0.05). At 3 months, ureteral strictures occurred in three patients in the traditional UAS group and one in the FANS group, a difference that was not statistically significant (P > 0.05). The overall complication rate was significantly lower in the FANS group (P < 0.05). For patients with IUUTS, fURS combined with FANS effectively improves stone clearance efficiency and reduces the risk of postoperative infection.

Humans↗