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Seventeen-year follow-up of hypophosphatasia diagnosed in middle-aged siblings harboring a novel intronic and a rare missense ALPL gene mutation.

Hypophosphatasia (HPP) is the rare inborn-error-of-metabolism that features impaired mineralization of the skeleton and teeth due to a deactivating mutation or mutations of the gene ALPL which encodes the tissue-nonspecific isoenzyme of alkaline phosphatase (TNSALP). We report 17-year follow-up of twin sisters and a brother referred in middle-age for painful proximal femoral "stress fractures" and then diagnosed with HPP. They reported generalized muscle and bone pain, metatarsal fractures, arthropathy and, since childhood, tooth loss. Their concordant findings were explained by compound heterozygosity in ALPL for a rare maternal missense mutation (c.1403C > T, p.Ala468Val) in exon 12, together with a novel presumably paternal change (c.863-14G > A) predicting a cryptic mRNA splice site in intron 8. Fractures continued during follow-up until one sister received a three-and-one-half-year course of hydroxyapatite-targeted TNSALP supplementation therapy (asfotase alfa) during which substantial improvement occurred in her clinical, biochemical, and functional parameters as well as quality of life. Following subsequent unplanned treatment cessation she suffered significant clinical deterioration, including new fractures and loss of mobility. Her bone histopathology documented osteomalacia. Treatment resumption restored its benefits. Among ten asymptomatic family members evaluated in this four-generation kindred, eight were carriers heterozygous for either ALPL mutation. Those harboring the maternal missense defect manifested mild hypophosphatasemia, suggesting a dominant-negative mutation effect. This experience underscores the importance of in-depth phenotyping and then clinical follow-up to characterize ALPL variant combinations, and for maintaining effective asfotase alfa treatment.

Humans

Genome mining of alkaliphilic cyanobacterial consortia: identification of biosynthetic gene clusters in Sodalinema and associated heterotrophs.

Alkaline soda lakes are high-pH environments that host specialized microbial communities with potential for biotechnology and natural product discovery. We characterized three Sodalinema-dominated cyanobacterial consortia enriched from Canadian soda lakes over 510 days. Using hybrid metagenomic sequencing and metatranscriptomics across pH, alkalinity, and temperature gradients, we reconstructed high-quality metagenome-assembled genomes and assessed functional activity. All consortia converged toward cyanobacteria dominance and exhibited temperature optima between 21°C and 30°C. Phylogenetic analysis placed Sodalinema genomes within a distinct clade affiliated with Candidatus Sodalinema alkaliphilum. Genomic analysis indicated complete biosynthetic pathways for vitamin B5, vitamin B7, and the molybdenum cofactor, but incomplete pathways for vitamins B1, B9, and B12, consistent with patterns observed in Sodalinema yuhuli. Metatranscriptomic profiles showed increased expression of genes involved in phycocyanin and carotenoid biosynthesis at pH 10.2 relative to pH 8.5. Biosynthetic gene cluster analysis revealed that most secondary metabolic potential resided in heterotrophic community members. Roseinatronobacter encoded pathways for N-acyl homoserine lactones, osmoprotectants, betalactones, and prodigiosin, while Alkalimonas, Wenzhouxiangella, and members of the Kiloniellales encoded clusters for lanthipeptides, cyclodipeptides, hydrogen cyanide, and pyrroloquinoline quinone. These findings indicate functional partitioning within the consortia and highlight the contribution of heterotrophs to secondary metabolism.IMPORTANCEAlkaline soda lakes contain microbial communities adapted to high pH that remain underexplored for biotechnology. This study focuses on Sodalinema, a filamentous cyanobacterium that dominates enriched consortia from Canadian soda lakes, and its associated heterotrophic partners. We show that while Sodalinema drives primary productivity, heterotrophic bacteria encode most of the pathways for antimicrobial and signaling compounds. These interactions may support community stability and defense against competing microorganisms. By linking genomic potential with gene expression, this work identifies alkaline cyanobacterial consortia as a source of bioactive compounds and provides a framework for exploring extremophilic microbial communities for natural product discovery.

Sodalinema

Retinoid dynamics in immune cells during age-related diseases.

Retinoids comprise vitamin A and its structurally related natural and synthetic derivatives. Retinoid dynamics involves multiple retinoid forms, carrier proteins, and enzymes that orchestrate the absorption, transport, storage and biotransformation of dietary vitamin A. Beyond their canonical metabolic functions, metabolites and proteins involved in retinoid metabolism also play distinct roles in signal transduction and transcriptome reprogramming, broadening the mechanisms that influence immune cell fate decisions. Age‑related changes in retinoid bioavailability and signaling intensity alter immune cell polarization and function, thereby contributing to the pathogenesis of chronic inflammation in neurodegenerative diseases, cardiovascular diseases, osteoarthritis, and other age-related diseases. In this review, we focus on age-related alterations in the retinoid metabolic pathway and their impact on inflammation and the progression of age-related diseases. This review highlights the pivotal role of retinoid metabolism in anti-ageing interventions and considers future directions and challenges in this field.

Humans

Pharmacological therapies for the prevention of fractures in men.

RATIONALE: Pharmacological therapies for fracture prevention usually target osteoporosis, a skeletal disorder characterised by compromised bone mass or quality (or both). As most participants in osteoporosis trials are women, a review of pharmacological therapies for fracture prevention in men was warranted. OBJECTIVES: To determine the benefits and harms of bisphosphonates, parathyroid (PTH) or parathyroid-related protein (PTHrP) analogues, denosumab, and romosozumab therapy for the prevention of fractures in men. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, and two trial registries (ClinicalTrials.gov and WHO ICTRP) until 14 October 2025, with no restrictions on date or language of publication. ELIGIBILITY CRITERIA: We included randomised controlled trials that compared bisphosphonates, PTH or PTHrP analogues, denosumab, or romosozumab (alone or with calcium or vitamin D, or both) with placebo, other drugs, or non-pharmacological therapies in men aged 50 years or older. Our primary comparison was bisphosphonates versus placebo. OUTCOMES: Critical outcomes were incidence of hip fractures, symptomatic vertebral fractures, other (not hip or vertebral) fractures, disability, participants with adverse events, study withdrawals due to adverse events, and participants with serious adverse events. Our primary time point was the final time point reported in the trials. RISK OF BIAS: We used Cochrane's RoB 2 tool to assess risk of bias. SYNTHESIS METHODS: We used a random-effects model for meta-analysis employing the Mantel-Haenszel approach, and the DerSimonian and Laird method to estimate between-trial variance. We assessed the certainty of evidence using GRADE. INCLUDED STUDIES: Seventeen trials (4132 participants) met our inclusion criteria. The average age of participants ranged from 52 to 73 years. Twelve trials used a placebo comparator versus bisphosphonate (7 trials, 2548 participants), PTH or PTHrP analogues (4 trials, 569 participants), denosumab (1 trial, 240 participants), and romosozumab (1 trial, 244 participants). For the other planned comparisons, a bisphosphonate was compared to vitamin D/vitamin D analogues (2 trials, 434 participants), to calcitonin (1 trial, 32 participants), to PTH or PTHrP analogues (1 trial, 19 participants), or to another bisphosphonate (1 trial, 301 participants), and one trial compared a bisphosphonate plus calcium to calcium tablets alone (46 participants). SYNTHESIS OF RESULTS: Placebo-controlled trials were largely susceptible to bias in selection of the reported result (83%), while most trials without a placebo control were also susceptible to bias arising from the randomisation process (100%) and in measurement of the outcome (80%). We are very uncertain about the effect of bisphosphonates on the incidence of hip fractures, symptomatic vertebral fractures, or other (non-hip non-vertebral) fractures compared to placebo at the final follow-up (up to two years). We downgraded the certainty of evidence once for risk of bias, twice for imprecision (very low event rates), and once for suspected publication bias. The certainty of evidence for incidence of other fractures was further downgraded for indirectness, as it was unclear if hip fractures were also included in the outcome. At up to two years, 2/875 participants (2 per 1000) in the bisphosphonate group reported hip fractures compared with 2/760 (3 per 1000) in the placebo group (risk ratio (RR) 0.73, 95% confidence interval (CI) 0.06 to 8.51; I² = 36%; 4 trials, 1635 participants); 5/1021 (4/1000) participants in the bisphosphonate group had a symptomatic vertebral fracture compared to 7/855 (8/1000) participants in the placebo group (RR 0.49, 95% CI 0.14 to 1.74; I² = 0%; 5 trials, 1876 participants); 25/1130 participants (16/1000) in the bisphosphonate group reported other (non-hip non-vertebral) fractures compared to 19/913 participants (21/1000) in the placebo group (RR 0.78, 95% CI 0.42 to 1.45; I² = 0%; 6 trials, 2043 participants). Bisphosphonates probably do not increase the risk of adverse events: 1024/1374 participants (746/1000) receiving bisphosphonates reported adverse events compared to 826/1174 participants (704/1000) receiving placebo (RR 1.06, 95% CI 0.93 to 1.19; I² = 75%; 7 trials, 2548 participants; moderate-certainty evidence) or serious adverse events: 329/1329 participants (272/1000) receiving bisphosphonate reported serious adverse events compared to 323/1128 participants (286/1000) receiving placebo (RR 0.95, 95% CI 0.84 to 1.08; I² = 0%; 6 trials, 2457 participants; moderate-certainty evidence). We downgraded the certainty of evidence once due to potential bias for adverse events and serious adverse events. We are very uncertain if bisphosphonates result in more withdrawals due to adverse events: 41/1374 participants (25/1000) in the bisphosphonate group withdrew due to adverse events compared with 43/1174 participants (37/1000) in the placebo group (RR 0.68, 95% CI 0.39 to 1.18; I² = 37%; 7 trials, 2548 participants; very low-certainty evidence). We downgraded the certainty of evidence once for risk of bias, once for indirectness, and once for imprecision. No trial reported disability. We are very uncertain about the effects of PTH or PTHrP analogues, denosumab, or romosozumab compared to placebo on fracture outcomes. We are very uncertain about the effects of PTH/PTHrP analogues on total adverse events, withdrawals due to adverse events, and serious adverse events. Denosumab may not increase the risk of adverse events or serious adverse events compared to placebo, while the evidence for withdrawals due to adverse events is very uncertain. Romosozumab probably does not increase the risk of adverse events and may not increase the risk of serious adverse events or result in more withdrawals due to adverse events. AUTHORS' CONCLUSIONS: We are very uncertain about the effects of bisphosphonates compared to placebo on the incidence of hip fractures, symptomatic vertebral fractures, or other (non-hip non-vertebral) fractures in men at up to two years of use. Bisphosphonates probably do not increase the risk of adverse events or serious adverse events, and we are very uncertain if they result in more withdrawals due to adverse events. We downgraded the certainty of evidence for indirectness, imprecision (low event rate), and serious risk of bias in selection of the reported result, as it was unclear if all studies fully reported every fracture. We found similar results for PTH or PTHrP analogues, denosumab, or romosozumab versus placebo. Larger, longer placebo-controlled studies are needed to determine whether pharmacological therapies are beneficial for reducing fractures in men. FUNDING: This Cochrane review had no dedicated funding. REGISTRATION: Protocol (2021): https://doi.org/10.1002/14651858.CD014707.

Humans

Metformin Adherence and Risk of Polyneuropathy in Type 2 Diabetes Mellitus: An International Matched Cohort Study with Independent Validation.

BACKGROUND: Metformin is a popular first-line glucose-lowering medication for type 2 diabetes mellitus (T2DM). Although metformin reduces the risks of various complications of diabetes, its potential to cause polyneuropathy by depleting vitamin B12 levels is concerning. This study investigated whether the adherence or discontinuation of metformin after adding-on a second-line antiglycemic agent increases the risk of polyneuropathy in patients with T2DM. METHODS: Data from TriNetX were obtained, and patients with T2DM who were receiving second-line antiglycemic agents were divided into metformin-adherent and metformin-nonadherent groups based on prescription claims data. Neuropathy incidence was evaluated using diagnostic claims and nerve conduction examinations. For independent confirmation and external validation of the primary findings, we used data from the National Health Insurance Research Database (NHIRD) of Taiwan. RESULTS: After matching, 58,027 patients were included in each group. Compared with metformin adherent patients, metformin nonadherent patients had a higher risk of polyneuropathy (adjusted hazard ratios [aHR] 1.26; 95% confidence interval [CI] 1.23-1.29; P < 0.001). Risks of diabetic foot ulcer, amputation, neuropathy-related medication use, and bone fracture were also higher among nonadherent patients. Sensitivity analyses confirmed the robustness of findings. In the validation NHIRD cohort (31,384 matched pairs), metformin nonadherence remained associated with increased polyneuropathy risk (aHR 1.25; 95% CI 1.10-1.42; P < 0.001). CONCLUSIONS: Metformin adherence in patients with T2DM who require second-line treatment may reduce the risk of polyneuropathy; vitamin B supplementation may enhance this benefit.

Humans

A smartphone-integrated Pt@Cu-HCF nanozyme-based paper sensor for on-site determination of total antioxidant capacity in marine oils.

Total antioxidant capacity (TAC) serves as a key indicator for evaluating the nutritional quality of foods. In this study, we designed a platinum-embedded copper hexacyanoferrate (denoted as Pt@Cu-HCF) nanozyme that exhibits high oxidase-like activity, efficiently catalyzing the oxidation of chromogenic substrates to generate robust colorimetric signals. Antioxidants quench hydroxyl radicals (&#x2219;OH) produced during the catalytic process, leading to a concentration-dependent suppression of the color signal. Leveraging this mechanism, a smartphone-integrated, colorimetric paper sensor for on-site TAC quantification was developed, using vitamin E as the calibration standard. The sensor was applied to determine TAC in fish oil, algal oil, and krill oil, demonstrating a linear response range of 9.78-312.5&#xa0;&#x3bc;M and a limit of detection (LOD) of 6.41&#xa0;&#x3bc;M. Validation using real-world marine oil samples showed excellent agreement with a commercial assay kit, confirming the reliability and practical applicability of this portable sensor for TAC measurement in complex biological matrices.

Antioxidants

Uncovering parental exposure risks of TCPP: Impaired development and metabolic homeostasis in zebrafish offspring.

As brominated flame retardants are phased out, tris (1&#x2011;chloro-2-propyl) phosphate (TCPP), a phosphorus-based flame retardant, has emerged as a prominent detectable flame retardant in the environment. However, TCPP has been found to exhibit endocrine-disrupting effects on organisms, raising significant safety concerns. In our study, we utilized the zebrafish model to explore the toxic effects of parental TCPP exposure on offspring and uncover its regulatory mechanisms through metabolomics analysis. Moreover, the impact on the nervous system and lipid metabolism was examined through behavioral analysis and specific staining. Our findings demonstrated that both embryonic and parental TCPP exposure induced developmental disorders in larvae, along with decreased locomotor activity and disordered lipid metabolism homeostasis. Parental exposure to TCPP, exhibiting stronger developmental toxicity than direct embryonic exposure, notably led to reductions in crucial energy substrates such as amino acids and carbohydrates. Meanwhile, embryonic TCPP exposure primarily affected the endogenous lipid-related metabolites including phospholipids, lipid-soluble vitamins, steroids and fatty acids, promoting lipid accumulation in larval liver and subcutaneous tissue. What's more, continuously parental and embryonic exposure showed the most pronounced effects on zebrafish development and metabolic regulation. Our study highlights the risk posed by parental exposure to TCPP on offspring zebrafish, underscoring the need for comprehensive consideration of the impact from parental exposure in pollutants regulation.

Animals

Early infantile developmental and epileptic encephalopathy: clinical spectrum, diagnosis, outcomes, and evolving treatment strategies.

Early infantile developmental and epileptic encephalopathy (EIDEE) is among the most severe epilepsy syndromes, with onset before three months of age and an estimated incidence of approximately 10 per 100,000 live births. The 2022 International League Against Epilepsy classification unified the historically distinct Ohtahara syndrome and early myoclonic encephalopathy under a single diagnostic framework defined by frequent drug-resistant tonic and/or myoclonic seizures, an abnormal neurological examination, and an abnormal interictal electroencephalogram-most characteristically a burst-suppression pattern. This narrative review synthesizes the clinical, electrophysiological, neuroimaging, genetic, and therapeutic literature within the EIDEE framework. The clinical phenotype is characterized by central hypotonia, postnatal microcephaly, cortical visual impairment, and age-dependent syndromic evolution toward infantile epileptic spasms syndrome or Lennox-Gastaut syndrome in the majority of patients. Electroencephalography remains essential for syndromic classification, while systematic metabolic screening and early trio whole-exome or whole-genome sequencing are central to the etiologic workup, achieving diagnostic yields of 60-65%. The most commonly identified genetic causes include STXBP1, KCNQ2, and SCN2A variants. Outcomes are poor overall and strongly etiology-dependent: vitamin-responsive disorders carry a substantially more favorable prognosis, whereas mortality reaches 25% in genetic cohorts. Genotype-guided pharmacotherapy is now applicable to a clinically meaningful subset of patients, with sodium channel blockers, potassium channel openers, and emerging antisense oligonucleotide therapies representing important therapeutic advances. Gene therapy trials are underway but have encountered early safety signals, underscoring the vulnerability of this population. Critical unmet needs include earlier molecular diagnosis, precision therapies targeting developmental outcomes beyond seizure control, and prospective international registries to characterize the long-term natural history of EIDEE.

Humans

Generation of spCAS9 expressing human mesenchymal stem cell line to study gene function during osteoblast differentiation.

Human bone marrow-derived stromal cells (hMSCs) are a great resource for studying how genes influence cell fate and differentiation into various cell types like osteoblasts, adipocytes, and chondrocytes, among other cell types. However, genetic manipulation of primary hMSCs has been challenging due to their short lifespan and cellular senescence after limited passaging. Their low and unstable transfection efficiency also complicates gene delivery or inactivation, hindering long-term functional studies. The limited lifespan has been effectively solved by immortalizing hMSCs with telomerase reverse transcriptase (hMSCs-TERT). The use of these cells is ideal for functional studies of osteoblast and adipocyte differentiation through genetic manipulation, providing a stable and reliable model. Here, we have engineered a stable CAS9 expressing hMSC-TERT cell line (hMSC-TERTCAS9) via lentiviral transduction. The constitutive expression of spCas9 enables efficient and reproducible gene editing. We demonstrate the potential of these hMSC-TERTCAS9 cells for generating gene disruptions using plasmid delivery of guide RNAs as a fast and efficient strategy for targeted genome editing. The edited cells can be sorted and expanded as single cells to obtain homogenous clonal cell lines with mono- as well as bi-allelic gene deletions, a crucial step for producing reliable experimental results. We further validate this cell line as a powerful tool for studying gene function during hMSC proliferation and differentiation, providing 3 distinct examples of its utility. Through the generation of indels, single-cell sorting, and clonal selection, we have efficiently inactivated the vitamin D receptor and created both larger (256 nucleotides) gene disruptions in Forkhead box protein O1 and precise removals of a small genomic sequence (73 nucleotides) coding for microRNA MIR675. This novel hMSC-TERTCAS9 cell line represents a significant advancement, offering a stable, efficient, and versatile platform for advanced genetic studies, high-throughput screening, and the creation of reliable cellular disease models.

CRISPR-Cas9

The Childhood Cancer and Leukemia International Consortium (CLIC): Expanding global collaboration in pediatric cancer etiology research.

Childhood cancers are rare, but incidence has risen modestly in countries with robust registration, partly reflecting improved diagnosis. In high-income countries, cancer is the leading cause of disease-related death in children. Marked inequities in incidence, survival, and research capacity underscore the need for large-scale collaboration to identify environmental, genetic, and contextual determinants of risk. The Childhood Cancer and Leukemia International Consortium (CLIC) was established in 2007 to study the etiology of childhood leukemia and later expanded in 2019 to include other childhood cancers, principally solid tumors. CLIC pools harmonized, individual-level data from case-control and cohort studies, obtained through interviews, record linkage (insurance claims, registries), or geographic information systems, and integrates germline genomic data where available. Membership has grown from 13 studies in 9 countries to 57 studies in 21 countries; recruitment spans the early 1960s to the present and encompasses approximately 150,000 cases across all tumor types and 300,000 controls with clinical, demographic, and exposure data, centralized via harmonized data dictionaries at the Data Coordination Center, established in 2014 at the International Agency for Research on Cancer, and supported by a secure analysis platform. Pooled analyses across diverse populations have implicated parental age, prenatal vitamin or folic acid use, mode of delivery, fetal growth, selected congenital anomalies, occupational or household exposures (e.g., pesticides), paternal smoking, and markers of early-life immune modulation (e.g., breastfeeding, daycare attendance) in leukemia risk, informing carcinogen evaluation and prevention. The integration of genetic ancestry and germline susceptibility data is clarifying ancestry-related differences in leukemia biology and outcomes, while confirming risk loci with population-specific effects. CLIC is now adding polygenic risk scores and exposomic data to refine etiologic subtyping and identify modifiable pathways, while broadening representation from underserved regions through partnership-building and capacity-strengthening.

Humans

Proteome-level evidence that tebuconazole, both alone and in interaction with thiacloprid, affects epigenetic events in bumblebee heads.

Tebuconazole, a widely used ergosterol biosynthesis-inhibiting fungicide, can affect nontargets, especially when combined with insecticides. We employed label-free quantitative proteomics to investigate the effects of long-term exposure to sublethal concentrations (100&#xa0;&#x3bc;g/L) of tebuconazole, either by itself or alongside the neonicotinoid thiacloprid (100&#xa0;&#x3bc;g/L), on the heads of Bombus terrestris workers. A Bayesian factor power analysis revealed that the experiment produced conclusive proteomic results. Tebuconazole treatment revealed eleven differentially abundant proteins, which increased elevenfold with thiacloprid. The proteins that changed in the same direction in both treatments suggest the occurrence of epigenetic events because they are involved in histone trimethylation (H3K4me3), pre-mRNA processing, and folate (vitamin B9) metabolism. Following co-exposure, the abundance of histone H2A.V and its associated proteins was affected. Two important detoxification-related proteins, CYP6BE1 and CYP6AQ1 (honey bee homologs), were identified, as well as proteins that suggest hormonal and neurotoxic effects. Overall, this study suggests that tebuconazole affects key epigenetic processes in bumblebee heads at the proteome level, though this was not confirmed at the biological level or through orthogonal methods. The tested chemicals were previously found to affect trimethylations, but not H3K4me3. We suggest analyzing the different trimethylations, their interplay, and associated hallmarks, such as folate levels. SIGNIFICANCE: The effects of pesticides and their combinations on organisms can be unexpected until they are examined using modern, complex methods. High-throughput proteomics can provide data on important biochemical processes affected by pesticides, offering a different perspective to that at the expression level. Despite their low acute toxicity, a group of fungicides that inhibit (ergo)sterol biosynthesis (EBI or SBI) are considered dangerous to pollinators, including bumblebees. This is due to the increasing toxicity of insecticides through the inhibition of cytochrome P450 detoxification enzymes. We found that tebuconazole had a similar effect on epigenetic events when used alone or in combination with the insecticide thiacloprid. Key proteins suggest that H3K4 histone trimethylation (H3K4me3) was impacted. To our knowledge, this expands the existing evidence suggesting that tebuconazole/triazole fungicides affect histone trimethylation H3K27me3. Since literature shows that thiacloprid affects H3K9me3, it is possible that thiacloprid and tebuconazole interact in these epigenetic events that affect each other. Overall, our results suggest that tebuconazole affects proteins involved in histone trimethylation, pre-mRNA processing, and folate metabolism. These are all hallmarks of epigenetic processes and were further extended by the co-exposure of tebuconazole and thiacloprid to more differently abundant proteins. Additionally, the results provide data on cytochrome P450s of the CYP6 family, which act as detoxifying proteins, as well as proteins that indicate hormonal and neurotoxic effects in bumblebee heads. Finally, the results of the Bayesian power analysis confirmed the meaningfulness of the proteomic data analyzed in this study. If the new findings obtained at the proteome level are verified by different methods, the full extent of the side effects of tebuconazole can be revealed.

Animals