Search Results (7,395)

Tissue engineering has the potential to overcome the limitations of using autografts in nerve gap repair, using cellular biomaterials to bridge the gap and support neuronal regeneration. Various types of therapeutic cells could be considered for use in aligned collagen-based engineered neural tissue (EngNT), including Schwann cells and their precursors, which can be derived from human induced pluripotent stem cells (hiPSCs). Using Schwann cell precursors may have practical advantages over mature Schwann cells as they expand readily in vitro and involve a shorter differentiation period. However, the performance of each cell type needs to be tested in EngNT. By adapting established protocols, hiPSCs were differentiated into Schwann cell precursors and Schwann cells, with distinctive molecular profiles confirmed using immunocytochemistry and RT-qPCR. For the first time, both cell types were incorporated into EngNT using gel aspiration–ejection, a technique used to align and simultaneously stabilise the cellular hydrogels. Both types of cellular constructs supported and guided aligned neurite outgrowth from adult rat dorsal root ganglion neurons in vitro. Initial experiments in a rat model of nerve gap injury demonstrated the extent to which the engrafted cells survived after 2 weeks and indicated that both types of hiPSC-derived cells supported the infiltration of host neurons, Schwann cells and endothelial cells. In summary, we show that human Schwann cell precursors promote infiltrating endogenous axons in a model of peripheral nerve injury to a greater degree than their terminally differentiated Schwann cell counterparts. Full article

Background/Objective: At least 25% of colorectal cancer (CRC) patients develop liver metastases (CRLM), and chemotherapeutic regimens based on the fluoropyrimidine (FP) drug 5-fluorouracil (5-FU) provide a survival advantage, but long-term survival is uncommon. The primary molecular target of FP drugs is thymidylate synthase (TS). Methods: A TS/Top1 dual-targeting cytotoxic mechanism for CF10/LV was confirmed by TS ternary complex detection by Western blot and by immunofluorescence detection of Top1 cleavage complexes. CF10/LV activated the ATR/Chk1 pathway consistent with enhanced replication stress and induced apoptosis. In vivo studies showed CF10 and CF10/LV eradicated liver metastasis in a CRLM model without scarring or weight loss, displaying therapeutic advantages relative to legacy FPs. Results: We demonstrated that a nanoscale FP polymer, CF10, displayed greater potency than expected based on FP content in part through more direct conversion to the TS-inhibitory metabolite, FdUMP. In this study, we tested CF10 for potency advantages relative to 5-FU and trifluorothymidine (TFT, the FP component of TAS-102) and confirmed a general potency advantage for CF10 in CRC cell lines in the Broad Institute PRISM screen. We demonstrated that this potency advantage is retained in CRC cells cultured with human-like folate levels and is enhanced by LV co-treatment to a similar extent as that by 5-FU. Our results confirm CF10 development proceeding as a CF10/LV combination. Mechanistically, CF10 cytotoxicity closely correlates with poisons of DNA topoisomerase 1 (Top1) in the PRISM screen relative to 5-FU and TFT. Conclusions: Our pre-clinical data support an early-phase clinical trial for CF10 for treating liver-metastatic CRC. Full article

Salmonella is a major foodborne pathogen that poses an increasing threat due to the emergence of mcr-1-mediated colistin resistance. However, data on mcr-1-positive Salmonella in pork products are limited. In this study, 457 samples collected in 2023 from pig slaughterhouses in Guangdong province were investigated to determine the prevalence and genomic characteristics of mcr-1-positive Salmonella isolates. We found that 92 Salmonella isolates (20.1%, 92/457) were recovered, representing six serotypes, including Salmonella Typhimurium (n = 29) and Salmonella Rissen (n = 29). High resistance to tetracycline (90.2%, 83/92) and multidrug resistance (58.7%, 54/92) were observed. Critically, two colistin-resistant Salmonella Kentucky ST198 isolates (2.2%) harboring mcr-1 on transferable IncI2 plasmids were identified. Genomic analysis revealed a novel multidrug resistance region (MRR, ~57 kb) inserted into the bcfH locus (containing floR, qnrS1, bla_CTX-M-55, and aph (3’)-Ia) and a variant Salmonella Genomic Island 1 (SGI1-KI, containing tet (A), sul1, qacEΔ1 and aadA7) in these isolates. The MRR and SGI1-KI may enhance bacterial survival under antibiotic selection pressure. Phylogenetic analysis showed close relatedness to human clinical strains, suggesting food chain transmission. The findings highlight a high antimicrobial resistance burden, the emergence of transferable last-resort colistin resistance (mcr-1), and acquisition of complex resistance determinants (MRR, SGI1-KI), underscoring an urgent need for enhanced “One Health” surveillance. Full article

Cisplatin is an effective chemotherapeutic drug, but is limited both by its toxicity and its tendency to induce drug resistance rapidly in some patients. Tissue transglutaminase 2 (TG2), which is overexpressed in various cancers, has two main isoforms: a long (TG2-L) and a short form (TG2-S). While TG2-L supports cell survival, conversely, TG2-S promotes cell death. Evidence increasingly suggests that TG2 may be a suitable target for combating chemoresistance in a variety of human cancers. Here, we show that cisplatin toxicity towards wild-type MCF-7 breast cancer cells is associated with reduced TG2-L and TG2-S expression, whereas approximately doubling the TG2-L expression through the retinoic acid pre-treatment of these cells induces survival in the presence of cisplatin at levels similar to those seen in long-term cisplatin-co-cultured cells, which have reduced sensitivity. The treatment of cisplatin-surviving cells with cisplatin alone did not significantly alter the levels of either TG2 isoform, whereas the cisplatin challenge of cisplatin-surviving MCF-7 cells following 20 µM retinoic acid pre-treatment resulted in increased levels of TG2-L, increased TG2 enzyme activity, and no significant change in TG2-S levels, with increased cell survival. These findings suggest a subtype-specific regulatory effect of RA in cisplatin-surviving MCF-7 cells, with TG2-L upregulated at higher RA concentrations, potentially contributing to altered cisplatin sensitivity. Anti-TG2 siRNA silencing reduced cisplatin IC50 to base levels in both wild-type and cisplatin-surviving MCF-7 cells, supporting the notion that the modulation of TG2 expression could offer a significant benefit to cisplatin efficacy. Preventing excessive retinoic acid exposure may also be a mechanism for maximising cisplatin efficacy, considering TG2 modulation. Full article

Background/Objectives: Human endogenous retroviruses (ERVs) are genomic sequences integrated into the human genome from ancestral exogenous retroviruses and are epigenetically silenced under normal conditions. Growing evidence has shown that they can be reactivated in human diseases such as cancers and autoimmune diseases. However, their clinical implications in colon cancer are yet to be explored. Methods: RNA-seq data were downloaded from RNA Atlas and TCGA for cell lines and tissue samples, respectively. After alignment, ERV expression was quantified against comprehensively compiled ERVs (3220). ERV expression profiles were compared between sequencing protocols, cancer and normal cells, and matched tumor and normal tissue pairs. Unsupervised clustering was used to identify ERV-defined tumor subtypes and their associations with clinical and other molecular features. ERV association with disease-specific survival (DSS) was performed using the Cox regression model. Results: PolyA and total RNA protocols were comparable in ERV expression detection. Cancer cells had significantly increased ERV expression and reactivation. Upregulated ERVs were significantly enriched in viral protein interactions with cytokine and cytokine receptors. ERV expression-defined tumor classes were significantly associated with tumor mutation burden and immuno-phenotypes such as antigen processing and presenting machinery and tumor immune infiltration score. Survival analysis identified 152 ERVs to be independently associated with DSS. Conclusions: ERV abnormal expression is common in colon cancer. The ERV-defined subtypes are associated with tumor immunity, and some ERVs are independently associated with patient outcomes. Full article

Background: Melanoma, the deadliest human skin cancer, frequently harbors activating BRAF mutations, with V600E being the most prevalent. These alterations drive constitutive activation of the MAPK pathway, promoting uncontrolled cell proliferation, survival, and dissemination. The advent of BRAFi and MEKi has significantly improved outcomes in BRAF V600-mutant melanoma. However, therapeutic resistance remains a major clinical barrier. Methods: This review integrates recent findings from preclinical and clinical studies to delineate resistance mechanisms to BRAF-targeted therapy. It categorizes resistance into primary (intrinsic), adaptive, and acquired forms, and analyzes their molecular underpinnings, including genetic and epigenetic alterations, pathway reactivation, and microenvironmental interactions. Results: Primary resistance is linked to pre-existing genetic and epigenetic changes that activate alternative signaling pathways, such as PI3K-AKT. Adaptive and acquired resistance includes secondary BRAF mutations, pathway redundancy, phenotype switching, and immune and stromal interactions. High-throughput sequencing has revealed novel mutations, including NRAS, NF1, and PTEN alterations, that contribute to resistance. Discussion: Understanding the multifaceted nature of resistance is critical to improving outcomes in advanced melanoma. This review highlights emerging strategies to overcome resistance, including combinatorial therapies, metabolic targeting, and biomarker-driven approaches, aiming to inform future therapeutic development and precision oncology strategies. Full article

Orphan nuclear receptor 4A1 (NR4A1) is a member of the NR4A subfamily that was initially discovered as an intermediate early gene expressed in response to stressors, including inflammatory agents. This review addresses the hypothesis that NR4A1 is a key nutrient sensor that contributes to the anti-aging and health-protective effects of receptor ligands, dietary phenolics, and other diet-derived compounds. There is evidence in animal models including humans that NR4A1 serves as an important gene that decreases the rate of aging and its associated diseases. For example, in humans and mice, NR4A1 expression decreases with age and loss of NR4A1 enhances disease susceptibility, and survival curves show that NR4A1-deficient mice live 4 months less than wild-type animals. An extensive comparison of inflammatory diseases, immune dysfunction, and fibrosis in multiple tissues shows that in NR4A1^−/− mice and rats these diseases and injuries are enhanced compared to wild-type NR4A1^−/− animals. There is evidence showing that structurally diverse NR4A1 ligands reverse the induced adverse effects in NR4A1 wild-type mice. This raises an important question regarding the mechanisms of NR4A1-dependent inhibition of the aging process and the potential for this receptor as a nutrient sensor. It has been well established that polyphenolics, including flavonoids, resveratrol, and other compounds in the diet, are health-protective and decrease the aging process. Recent studies show that resveratrol and flavonoids such as quercetin and kaempferol bind NR4A1 and exhibit protective NR4A1-dependent inhibition of endometriosis and cancer. These limited studies support a role for NR4A1 as a potential dietary sensor of nutrients that are known to be health-protective and a potential nutrient target for improving health. Full article

Escherichia coli O157:H7 has been an important foodborne pathogen causing severe disease in humans worldwide. It is challenging to control E. coli O157:H7 due to its intrinsic acid resistance, ability to survive in various environments, and the emergence of antimicrobial resistance. Recent research showed that phages are promising antibacterial agents. A phage (Φ241) infecting 48 E. coli O157:H7 strains from various sources was previously isolated from an industrial cucumber fermentation at pH 3.7 and 5% NaCl. The efficacy of phage Φ241 infection was evaluated in this study in four representative model food systems (beef broth, cucumber juice, cucumber juice supplemented with NaCl, and apple juice). Pronounced differences in phage effectiveness were found in the tested food systems, and impacted by pH, salinity, and multiplicity of infection. The potential of this phage is evident in beef broth and cucumber juice, where 4- to 6-log reduction in host concentration was achieved within 3 to 5 h. However, apple juice (pH 3.55) completely inhibited host growth and phage infection. Overall, the study shows the high potential of Φ241 as an antibacterial agent to improve food safety. Future research will incorporate a cocktail of phages targeting E. coli O157:H7 to mitigate phage resistance development. Full article

The Helicobacter pylori vapD gene is transcribed and expressed when the bacteria are within the gastric cell. In this current study, we investigated how vapD knockout affects the survival of H. pylori inside human gastric adenocarcinoma cells. We constructed an H. pylori 26695 vapD (Hp ΔvapD) mutant strain. H. pylori 26695 wt and Hp ΔvapD strains were grown in synthetic media and were co-cultured with AGS cells. From the start, the growth curve, total protein concentration and colony-forming units (CFUs) of each strain were measured. From each co-culture, CFUs and total RNA were obtained, and transcript levels of GAPDH, vapD, vacA, ureA, and 16s Hp were measured by qRT-PCR. Hp ΔvapD did not affect the growth rate of the strain in synthetic media, showing that the vapD gene is not necessary when the bacteria grow outside eukaryote cells. However, in the intracellular environment, the number of CFUs recovered from the Hp ΔvapD strain from AGS cells decreased after 36 h. Transcription levels of the vacA gene from the Hp ΔvapD strain were 10,000-fold lower than those of H. pylori wt, to the point of being undetectable. The results suggest that the vapD gene contributed to maintaining H. pylori inside gastric cells. Full article

Vitiligo is a chronic autoimmune dermatosis defined by selective melanocyte depletion and patchy depigmentation. IFN–γ-driven recruitment of autoreactive CD8⁺ T cells and induction of melanocyte apoptosis are central to its pathogenesis. Current therapies—including UVB phototherapy, tacrolimus, vitamin D3 analogs, and surgical methods—show limited and inconsistent efficacy. Emerging treatments like JAK inhibitors and WNT activators offer potential but require further validation. Translational progress is hindered by a lack of scalable human models. Here, we describe a tunable in vitro vitiligo platform in which human iPSC-derived melanocytes (iMc) are co-cultured with keratinocytes on Matrigel and exposed to precise graded IFN-γ concentrations. Our data revealed dose-dependent decreases in iMc survival and dendritic structure, faithfully mirroring derived melanocyte pathology. Leveraging this platform, we first evaluated the short-term efficacy of the ROCK inhibitor Y27632 under early-stage patient IFN-γ concentrations representative of patient lesional thresholds. At three days, Y27632 significantly upregulated adhesion molecules E-cadherin and DDR1, and two central factors—ET1 and bFGF. Importantly, ROCK inhibition reversed dendritic retraction and improved overall viability of iMc-keratinocytes. These findings position ROCK blockade as a promising adjunctive strategy and establish a pre-clinical platform for evaluating combination therapies for durable pigment restoration. Full article

There is a growing interest in using essential oils with phytoprotectant properties instead of synthetic pesticides to mitigate the risks of insect pesticide resistance, environmental harm, and adverse effects on non-target organisms and human health. This study focused on the effects of Coridothymus capitatus essential oil on host selection, settling behaviour, and survival of Macrosiphoniella sanborni in dual-choice and no-choice tests. The essential oil and methanol extract of C. capitatus were analyzed using Gas Chromatography–Mass Spectrometry (GC-MS) and Liquid Chromatography–Mass Spectrometry (LTQ-LC-MS Orbitrap), respectively. The antioxidant activity was also tested through the radical scavenging assay. The settling inhibitory activity in the dual-choice test increased dose-dependently from 60% to 72% for essential oil concentrations of 0.1 to 0.3% (v/v) for up to 120 min exposure, but decreased thereafter. However, under no-choice conditions, the inhibitory effect after 60 min of exposure was inversely proportional to the concentration but became proportional by the end of the experiment (72 h). After 72 h, both assays produced a mortality rate of 15% to 17%. C. capitatus was classified as a Carvacrol chemotype. Fifteen phenolic compounds were identified in the MeOH extract, and both the extract and essential oil exhibited substantial antioxidant activity. In conclusion, our findings indicate that C. capitatus essential oil affects the behaviour and survival of M. sanborni. Full article

Acute human alpha-herpesvirus 1 (HSV-1) infection culminates in a latent infection of neurons in trigeminal ganglia (TG) and the central nervous system. Following infection of mucosal epithelial cells, certain neurons survive infection and life-long latency is established. Periodically, stressful stimuli trigger reactivation from latency, which result in virus shedding, transmission to other people, and, occasionally, recurrent disease. The glucocorticoid receptor (GR) and Krüppel-like factor 15 (KLF15) comprise a feed-forward transcriptional loop that cooperatively transactivate key HSV-1 promoters that drive expression of infected cell protein 0 (ICP0), ICP4, and ICP27. Silencing KLF15 significantly reduces HSV-1 replication in cultured mouse neuroblastoma cells. Consequently, we hypothesized that KLF15 mediates certain aspects of reactivation from latency. To test this hypothesis, we compared HSV-1 replication in KLF15^−/− mice versus wild-type (wt) parental C57BL/6 mice. Virus shedding during acute infection was reduced in KLF15^−/− mice. Male KLF15^−/− mice shed higher titers of virus during late stages of reactivation from latency compared to KLF15^−/− females and wt mice regardless of sex. At 15 d after explant-induced reactivation, virus shedding was higher in male KLF15^−/− mice relative to wt mice and female KLF15^−/− mice. These studies confirm KLF15 expression enhances viral replication during acute infection and reactivation from latency. Full article

Multi-drug resistance in human bacterial pathogens has become a significant challenge for global healthcare this century, mainly due to the widespread misuse of antibiotics worldwide. As a result, millions of people have been affected by multi-drug-resistant bacterial infections. The antibiotic development pipelines cannot cope with the need to produce new antibiotics. Therefore, more productive antibiotic development methods must be invented. This paper presents an entirely rational approach for antibacterial drug discovery based on chimeric antisense oligonucleotide targeting (ASO) of the adenylate kinase mRNA in Staphylococcus aureus. The ASO is delivered into the bacteria via the cell-penetrating oligopeptide pVEC. The pVEC-ASO1 exhibits a bactericidal effect against Staphylococcus aureus, with a 50% minimal inhibitory concentration of 500 nM. The pVEC-ASO1 has a 98% survivability rate at the same concentration on cell lines. These findings strongly suggest that this chimeric ASO is a promising antibacterial drug candidate. Moreover, this is the fifth bacterial mRNA we have successfully targeted with pVEC-ASOs, providing further evidence for the efficiency of our approach. In contrast to the previous four targets, riboswitches residing in the 5′-untranslated region, we target the coding part of mRNA found in bacteria. That suggests that our approach may have much broader therapeutic applications. Full article

As large language model (LLM) tutors evolve from scripted helpers into adaptive educational partners, their capacity for self-regulation, ethical decision-making, and internal monitoring will become increasingly critical. This paper introduces the Needs-Driven Consciousness Framework (NDCF) as a novel, integrative architecture that combines Dennett’s multiple drafts model, Damasio’s somatic marker hypothesis, and Tulving’s tripartite memory system into a unified motivational design for synthetic consciousness. The NDCF defines three core regulators, specifically Survive (system stability and safety), Thrive (autonomy, competence, relatedness), and Excel (creativity, ethical reasoning, long-term purpose). In addition, there is a proposed supervisory Protect layer that detects value drift and overrides unsafe behaviours. The core regulators compute internal need satisfaction states and urgency gradients, feeding into a softmax-based control system for context-sensitive action selection. The framework proposes measurable internal signals (e.g., utility gradients, conflict intensity Ω), behavioural signatures (e.g., metacognitive prompts, pedagogical shifts), and three falsifiable predictions for educational AI testbeds. By embedding these layered needs directly into AI governance, the NDCF offers (i) a psychologically and biologically grounded model of emergent machine consciousness, (ii) a practical approach to building empathetic, self-regulating AI tutors, and (iii) a testable platform for comparing competing consciousness theories through implementation. Ultimately, the NDCF provides a path toward the development of AI tutors that are capable of transparent reasoning, dynamic adaptation, and meaningful human-like relationships, while maintaining safety, ethical coherence, and long-term alignment with human well-being. Full article

Background: Pancreatic cancer ranks as the fourth leading cause of cancer-related deaths in the USA. The human aldehyde dehydrogenase (ALDH) family comprises 19 functional members and has been implicated in prognosis and therapy resistance. However, it remains unclear which specific ALDHs are associated with adverse prognoses in pancreatic cancer. Methods: We obtained transcriptomic and clinical data for pancreatic adenocarcinoma (PAAD) from the TCGA, corresponding mutational data, and normal pancreatic tissue transcriptomic data from GTEx. Prognostic analysis was carried out using Kaplan–Meier analysis. KEGG and GO analyses were used for biological signaling pathways, and ESTIMATE algorithms were used for tumor microenvironment (TME) assessment. CIBERSORT algorithm, immune infiltration analysis, and OncoPredict algorithms were employed for predicting chemotherapy sensitivity. Results: Our study identified four of the 19 ALDH genes (ALDH1L1, ALDH3A1, ALDH3B1, ALDH5A1) that were significantly associated with pancreatic cancer prognosis. High expression of ALDH1L1, ALDH3A1, and ALDH3B1 was associated with shorter overall survival, while ALDH5A1 expression was associated with longer overall survival of pancreatic cancer patients. Clinicopathological analysis revealed a significant association with KRAS mutational status and ALDH3A1 expression. Immune correlation analysis indicated that high expression of ALDH3A1 and ALDH3B1 was associated with lower expression of CD8⁺ T cell-associated gene expression. ESTIMATE analyses further revealed that high expression of ALDH3A1 and ALDH3B1 was associated with lower levels of immune cell infiltration. PAAD tumors with low ALDH3A1 expression were more sensitive to paclitaxel. Immunohistochemical analysis demonstrated high expression of ALDH3A1 in pancreatic cancer cells of human tumor tissues compared to normal pancreatic tissues. Conclusions: This study unveils specific ALDH family members relevant for prognosis and chemotherapy response in pancreatic cancer patients. These findings contribute valuable insights into prognostic biomarkers and their potential clinical utility in the treatment of pancreatic adenocarcinoma. Full article