The prognostic role of pre-treatment neutrophil to lymphocyte ratio and platelet to lymphocyte ratio in esophageal squamous cell carcinoma treated with concurrent chemoradiotherapy.

PURPOSE: In this study, we retrospectively investigated the prognostic role of pre-treatment neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) in esophageal squamous cell carcinoma patients (ESCC) treated with concurrent chemo-radiotherapy (CCRT). METHODS: We retrospectively analyzed the records of 338 patients with pathologically diagnosed esophageal squamous cell carcinoma that underwent concurrent chemo-radiotherapy from January 2013 to December 2017. Univariate and multivariate analyses were used to identify prognostic factors for progression free survival (PFS) and overall survival (OS). RESULTS: The result showed that the thresholds for NLR and PLR were 2.47 and 136.0 by receiver operating characteristic curve. High NLR and PLR were both associated with tumor length (P < 0.05). High NLR and PLR were significantly associated with poor PFS and OS. Multivariate analyses identified NLR, PLR and TNM stage were independent risk factors for PFS and OS. CONCLUSIONS: We show that the pre-treatment NLR and PLR may serve as prognostic indicators for esophageal squamous cell carcinoma treated with concurrent chemo-radiotherapy.

The subcommissural organ regulates brain development via secreted peptides.

The subcommissural organ (SCO) is a gland located at the entrance of the aqueduct of Sylvius in the brain. It exists in species as distantly related as amphioxus and humans, but its function is largely unknown. To explore its function, we compared transcriptomes of SCO and non-SCO brain regions and found three genes, Sspo, Car3, and Spdef, that are highly expressed in the SCO. Mouse strains expressing Cre recombinase from endogenous promoter/enhancer elements of these genes were used to genetically ablate SCO cells during embryonic development, resulting in severe hydrocephalus and defects in neuronal migration and development of neuronal axons and dendrites. Unbiased peptidomic analysis revealed enrichment of three SCO-derived peptides, namely thymosin beta 4, thymosin beta 10, and NP24, and their reintroduction into SCO-ablated brain ventricles substantially rescued developmental defects. Together, these data identify a critical role for the SCO in brain development.

Thrombosis inhibited by Corydalis decumbens through regulating PI3K-Akt pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Corydalis decumbens (Thunb.) Pers. was used as stasis-eliminating medicine traditionally to treat cardiovascular disease potentially attributed to its antithrombotic effect, but lack of pharmacological research on it. AIM OF THE STUDY: To investigate the antithrombotic effect of C. decumbens and its preliminary mechanism. MATERIALS AND METHODS: A carrageenan-induced mouse thrombus model and adenosine diphosphate stimulated platelet aggregation of rabbits were used to confirm the inhibitory effect of C. decumbens extract and compounds on thrombosis in vivo. Then, H2O2-induced human umbilical vein endothelial cells (HUVECs) injury model was further adopted to verify the effects of bioactive compounds in vitro. Moreover, in silico network pharmacology analyses and molecular docking were performed to predict the underlying mechanisms, targets, and pathways, and which were further confirmed through western blotting assay. RESULTS: The administration of total extract (TE), total alkaloids (TA) and tetrahydropalmatine (TET) resulted in a significant reduction in black tail thrombus and congestion, along with a decreasing in platelet aggregation of rabbits. A superior antithrombotic effect indicated the bioactive fraction, and then the isolated bioactive compounds, TET and protopine (PRO) increased cell survival, and decreased reactive oxygen species (ROS) and lactate dehydrogenase (LDH) release in H2O2-induced HUVECs injury model. Moreover, the two alkaloids targeted 33 major proteins and influenced 153 pathways in network pharmacology prediction. Among these, HSP90AA1, COX-2, NF-κB/p65, MMP1 and HIF-1α were the key proteins and PI3K-Akt emerged as the major signaling pathway. Further western blotting results supported that five key proteins were downregulated by the two bioactive compounds in H2O2-stimulated HUVECs model. CONCLUSION: C. decumbens exerted protective effect on thrombosis through inhibiting PI3K-Akt pathway and related key proteins, which supported the traditional use and presented potential antithrombotic alkaloids for further investigation.

Inter-organ steroid hormone signaling promotes myoblast fusion via direct transcriptional regulation of a single key effector gene.

Steroid hormones regulate tissue development and physiology by modulating the transcription of a broad spectrum of genes. In insects, the principal steroid hormones, ecdysteroids, trigger the expression of thousands of genes through a cascade of transcription factors (TFs) to coordinate developmental transitions such as larval molting and metamorphosis. However, whether ecdysteroid signaling can bypass transcriptional hierarchies to exert its function in individual developmental processes is unclear. Here, we report that a single non-TF effector gene mediates the transcriptional output of ecdysteroid signaling in Drosophila myoblast fusion, a critical step in muscle development and differentiation. Specifically, we show that the 20-hydroxyecdysone (commonly referred to as "ecdysone") secreted from an extraembryonic tissue, amnioserosa, acts on embryonic muscle cells to directly activate the expression of antisocial (ants), which encodes an essential scaffold protein enriched at the fusogenic synapse. Not only is ants transcription directly regulated by the heterodimeric ecdysone receptor complex composed of ecdysone receptor (EcR) and ultraspiracle (USP) via ecdysone-response elements but also more strikingly, expression of ants alone is sufficient to rescue the myoblast fusion defect in ecdysone signaling-deficient mutants. We further show that EcR/USP and a muscle-specific TF Twist synergistically activate ants expression in vitro and in vivo. Taken together, our study provides the first example of a steroid hormone directly activating the expression of a single key non-TF effector gene to regulate a developmental process via inter-organ signaling and provides a new paradigm for understanding steroid hormone signaling in other developmental and physiological processes.

ZMYND8 protects breast cancer stem cells against oxidative stress and ferroptosis through activation of NRF2.

Breast cancer stem cells (BCSCs) mitigate oxidative stress to maintain their viability and plasticity. However, the regulatory mechanism of oxidative stress in BCSCs remains unclear. We recently found that the histone reader ZMYND8 was upregulated in BCSCs. Here, we showed that ZMYND8 reduced ROS and iron to inhibit ferroptosis in aldehyde dehydrogenase-high (ALDHhi) BCSCs, leading to BCSC expansion and tumor initiation in mice. The underlying mechanism involved a two-fold posttranslational regulation of nuclear factor erythroid 2-related factor 2 (NRF2). ZMYND8 increased stability of NRF2 protein through KEAP1 silencing. On the other hand, ZMYND8 interacted with and recruited NRF2 to the promoters of antioxidant genes to enhance gene transcription in mammospheres. NRF2 phenocopied ZMYND8 to enhance BCSC stemness and tumor initiation by inhibiting ROS and ferroptosis. Loss of NRF2 counteracted ZMYND8's effects on antioxidant genes and ROS in mammospheres. Interestingly, ZMYND8 expression was directly controlled by NRF2 in mammospheres. Collectively, these findings uncover a positive feedback loop that amplifies the antioxidant defense mechanism sustaining BCSC survival and stemness.

E3 ubiquitin ligase Herc3 deficiency leads to accumulation of subretinal microglia and retinal neurodegeneration.

Activated microglia have been implicated in the pathogenesis of age-related macular degeneration (AMD), diabetic retinopathy, and other neurodegenerative and neuroinflammatory disorders, but our understanding of the mechanisms behind their activation is in infant stages. With the goal of identifying novel genes associated with microglial activation in the retina, we applied a semiquantitative fundus spot scoring scale to an unbiased, state-of-the-science mouse forward genetics pipeline. A mutation in the gene encoding the E3 ubiquitin ligase Herc3 led to prominent accumulation of fundus spots. CRISPR mutagenesis was used to generate Herc3-/- mice, which developed prominent accumulation of fundus spots and corresponding activated Iba1 + /CD16 + subretinal microglia, retinal thinning on OCT and histology, and functional deficits by Optomotory and electrophysiology. Bulk RNA sequencing identified activation of inflammatory pathways and differentially expressed genes involved in the modulation of microglial activation. Thus, despite the known expression of multiple E3 ubiquitin ligases in the retina, we identified a non-redundant role for Herc3 in retinal homeostasis. Our findings are significant given that a dysregulated ubiquitin-proteasome system (UPS) is important in prevalent retinal diseases, in which activated microglia appear to play a role. This association between Herc3 deficiency, retinal microglial activation and retinal degeneration merits further study.

Chiral Supramolecular Nanofibers Regulated Tumor-Derived Exosomes Secretion for Constructing an Anti-Tumor Extracellular Microenvironment.

Tumor-derived exosomes (TDEs) induced extracellular microenvironment has recently been validated to be critical for tumor progression and metastasis, however, remodeling it for oncotherapy still remains a major challenge due to difficulty in regulation of TDEs secretion. Herein, the supramolecular chiral nanofibers, composed of L/D -phenylalanine derivates (L/D-Phe) and linear hyaluronic acid (HA), are successfully employed to construct TDEs induced anti-tumor extracellular microenvironment. The left-handed L-Phe @HA nanofibers significantly inhibit TDEs secretion into extracellular microenvironment, which results in suppression of tumor proliferation and metastasis in vitro and vivo. Biological assays and theoretical modeling reveal that these results are mainly attributed to strong adsorption of the key exosomes transporters (Ras-related protein Rab-27A and synaptosome-associated protein 23) on left-handed L-Phe @HA nanofibers via enhanced stereoselective interaction, leading to degradation and phosphorylated dropping of exosomes transporters. Subsequently, transfer function of exosomes transporters is limited, which causes remarkable inhibition of TDEs secretion. These findings provide a promising novel insight of chiral functional materials to establish an anti-tumor extracellular microenvironment via regulation of TDEs secretion.

Antimicrobial ingredients of Zanthoxylum motuoense and potential in fresh pork meat preservation.

Zanthoxylum motuoense (Tibetan prickly ash, MTHJ), different from the Chinese prickly ash species, is distributed only in the Tibet. Now the chemical characterization and antibacterial activity of MTHJ extracts were analyzed for the first time. As a result, Schinifoline (12), γ-Fagarine (8), (2E,7E,9E)-6 S-Hydroxy-N-(2-methylpropyl)-11-oxo-2, 7, 9-Dodecatrienamide (6), and Neoechinulin A (17) were found to be the major different factors by untarget LC-MS metabolomics together with quantitative analysis on target. These four compounds were also the major antibacterial constituents. Then, the antimicrobial activity of MTHJ fractions was evaluated with colony forming units (CFU), fluorescence microscopy imaging, SEM and investigating the potential food preservation. Nutritional composition, colour and sensory evaluation of extract-treated samples were evaluated along storage time. The results suggested the MTHJ may be used for meat products preservation, and the scores were significantly higher for its unique flavor, which offered a promising choice for food safety, preservation and reducing foodborne illness.

An inappropriate decline in ribosome levels drives a diverse set of neurodevelopmental disorders.

Many neurodevelopmental defects are linked to perturbations in genes involved in housekeeping functions, such as those encoding ribosome biogenesis factors. However, how reductions in ribosome biogenesis can result in tissue and developmental specific defects remains a mystery. Here we describe new allelic variants in the ribosome biogenesis factor AIRIM primarily associated with neurodevelopmental disorders. Using human cerebral organoids in combination with proteomic analysis, single-cell transcriptome analysis across multiple developmental stages, and single organoid translatome analysis, we identify a previously unappreciated mechanism linking changes in ribosome levels and the timing of cell fate specification during early brain development. We find ribosome levels decrease during neuroepithelial differentiation, making differentiating cells particularly vulnerable to perturbations in ribosome biogenesis during this time. Reduced ribosome availability more profoundly impacts the translation of specific transcripts, disrupting both survival and cell fate commitment of transitioning neuroepithelia. Enhancing mTOR activity by both genetic and pharmacologic approaches ameliorates the growth and developmental defects associated with intellectual disability linked variants, identifying potential treatment options for specific brain ribosomopathies. This work reveals the cellular and molecular origins of protein synthesis defect-related disorders of human brain development. Highlights: AIRIM variants reduce ribosome levels specifically in neural progenitor cells. Inappropriately low ribosome levels cause a transient delay in radial glia fate commitment.Reduced ribosome levels impair translation of a selected subset of mRNAs.Genetic and pharmacologic activation of mTORC1 suppresses AIRIM-linked phenotypes.

Early-onset diabetes mellitus as a presenting feature of Werner's syndrome in an Indian family.

BACKGROUND: Diabetes mellitus (DM) in children and adolescents is typically caused by type 1 DM, followed by type 2 DM and maturity-onset diabetes of the young (MODY). We report an unusual Asian Indian family in which three members presented with DM at ages 15, 20, and 30, but not fitting the typical clinical picture of type 1 DM, type 2 DM, or MODY. The primary objective was to elucidate the molecular genetic basis of DM in this family. METHODS: The proband, a 22-year-old man, had short stature, gray hair, osteoporosis, and markedly reduced subcutaneous fat on the body, especially on the extremities along with acanthosis nigricans, and developed myxoid malignant peripheral nerve sheath tumor. Detailed family history revealed multiple loops of consanguinity. The proband underwent whole-genome sequencing, and seven relatives underwent whole-exome sequencing. RESULTS: The proband and three additional family members were found to have the homozygous c.561A>G nucleotide variant of WRN RecQ-like helicase (WRN) gene consistent with the diagnosis of Werner's syndrome. The c.561A>G variant induces a new splicing site on exon 6 resulting in a truncated WRN protein, p.Lys187Trpfs*13. CONCLUSION: Our report brings to attention the onset of DM during childhood or early adulthood in patients with Werner's syndrome who typically develop type 2 DM around the age of 30-40 years. Presence of consanguinity among parents, dysmorphic features, and malignancy should prompt consideration of diagnosis of Werner's syndrome.

Transcriptomic meta-analysis reveals ERRα-mediated oxidative phosphorylation is downregulated in Fuchs' endothelial corneal dystrophy.

BACKGROUND: Late-onset Fuchs' endothelial corneal dystrophy (FECD) is a degenerative disease of cornea and the leading indication for corneal transplantation. Genetically, FECD patients can be categorized as with (RE+) or without (RE-) the CTG trinucleotide repeat expansion in the transcription factor 4 gene. The molecular mechanisms underlying FECD remain unclear, though there are plausible pathogenic models proposed for RE+ FECD. METHOD: In this study, we performed a meta-analysis on RNA sequencing datasets of FECD corneal endothelium including 3 RE+ datasets and 2 RE- datasets, aiming to compare the transcriptomic profiles of RE+ and RE- FECD. Gene differential expression analysis, co-expression networks analysis, and pathway analysis were conducted. RESULTS: There was a striking similarity between RE+ and RE- transcriptomes. There were 1,184 genes significantly upregulated and 1,018 genes significantly downregulated in both RE+ and RE- cases. Pathway analysis identified multiple biological processes significantly enriched in both-mitochondrial functions, energy-related processes, ER-nucleus signaling pathway, demethylation, and RNA splicing were negatively enriched, whereas small GTPase mediated signaling, actin-filament processes, extracellular matrix organization, stem cell differentiation, and neutrophil mediated immunity were positively enriched. The translational initiation process was downregulated in the RE+ transcriptomes. Gene co-expression analysis identified modules with relatively distinct biological processes enriched including downregulation of mitochondrial respiratory chain complex assembly. The majority of oxidative phosphorylation (OXPHOS) subunit genes, as well as their upstream regulator gene estrogen-related receptor alpha (ESRRA), encoding ERRα, were downregulated in both RE+ and RE- cases, and the expression level of ESRRA was correlated with that of OXPHOS subunit genes. CONCLUSION: Meta-analysis increased the power of detecting differentially expressed genes. Integrating differential expression analysis with co-expression analysis helped understand the underlying molecular mechanisms. FECD RE+ and RE- transcriptomic profiles are much alike with the hallmark of downregulation of genes in pathways related to ERRα-mediated OXPHOS.

Neonatal methicillin-resistant Staphylococcus aureus pneumonia-related recurrent fatal pyopneumothorax: A case report and review of literature.

BACKGROUND: Although neonatal Staphylococcus aureus pneumonia is common and usually curable, it can also be refractory and life-threatening. Herein, we report a case of severe neonatal community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) necrotizing pneumonia with bilateral recurrent pyopneumothorax, respiratory failure, heart failure, and cardiac arrest. We hope our report will add to the understanding of this disease. CASE SUMMARY: An 18-d-old boy presented with cough for five days, fever for three days, and dyspnea for two days. Preadmission chest radiograph revealed high-density shadows in both lungs. On admission, his oxygen saturation fluctuated around 90% under synchronized intermittent mandatory ventilation. He was unconscious, with dyspnea, weak heart sounds and hepatomegaly. Moist crackles were present throughout his left lung, while the breath sounds in the right lung were decreased. After high-frequency oscillatory ventilation, empiric antimicrobials (meropenem and vancomycin), improved circulation, and right pleural cavity drainage for right pneumothorax (approximately 90% compression), his oxygen saturation level stayed above 95%, and recruitment of the right lung was observed. His condition did not deteriorate until the 5th day of hospitalization (DOH 5). On the morning of DOH 5, his oxygen saturation decreased. Subsequent chest radiograph showed bilateral pneumothorax with nearly 100% compression of the left lung. Desaturation was not relieved after urgent left pleural cavity drainage, and cardiac arrest occurred soon thereafter. Although his spontaneous heartbeat returned through emergency resuscitation and salvage antibacterial therapy (linezolid and levofloxacin) was administered given the detection and antimicrobial susceptibility of MRSA, he showed no improvement, with recurrent pyopneumothorax and continued drainage of purulent fluid and necrotic lung tissue fragments from the pleural cavity. Eventually, his parents refused extracorporeal membrane oxygenation (ECMO) and gave up all the treatments, and the newborn passed away soon after withdrawal on DOH 13. CONCLUSION: Neonatal MRSA pneumonia can be refractory and lethal, especially in cases where necrotizing pneumonia leads to extensive lung necrosis and recurrent pneumothorax. Despite treatment with linezolid and other medical measures, it may still be ineffective. Currently, ECMO has been a remedial therapy, but if the lung tissue is too severely eroded to be repaired, it may be useless unless the infection can be controlled and lung transplantation can be performed. Regardless of whether ECMO is initiated, the key to successful treatment is to achieve control over the pneumonia caused by MRSA as soon as possible and to reverse lung injury as much as possible.

An improved method for the synthesis and formation mechanism of M2B10H14 based on the reactions of B10H14 with MNH2BH3 (M = Na, K).

An efficient method for the synthesis of M2B10H14 (M = Na and K) has been developed. The two possible formation mechanisms of the B10H142- anion are proposed, in which the NH2BH3- anion acts as a proton abstractor and a hydride donor. Furthermore, the B10H13- and B10H15- intermediates were detected.

Impact of gravity on fluid flow and solute transport in the bone lacunar-canalicular system: a multiscale numerical simulation study.

Different gravity fields have important effects on the structural morphology of bone. The fluid flow caused by loadings in the bone lacunar-canalicular system (LCS), converts mechanical signals into biological signals and regulates bone reconstruction by affecting effector cells, which ensures the efficient transport of signaling molecules, nutrients, and waste products. In this study, the fluid flow and mass transfer effects of bone lacunar-canalicular system at multi-scale were firstly investigated, and a three-dimensional axisymmetric fluid-solid coupled finite element model of the LCS within three continuous osteocytes was established. The changes in fluid pressure field, flow velocity field, and fluid shear force variation on the surface of osteocytes within the LCS were studied comparatively under different gravitational fields (0 G, 1 G, 5 G), frequencies (1 Hz, 1.5 Hz, 2 Hz) and forms of cyclic compressive loading. The results showed that different frequencies represented different exercise intensities, suggesting that high-intensity exercise may accelerate the fluid flow rate within the LCS and enhance osteocytes activity. Hypergravity enhanced the transport of solute molecules, nutrients, and signaling molecules within the LCS. Conversely, the mass transfer in the LCS may be inhibited under microgravity, which may cause bone loss and eventually lead to the onset of osteoporosis. This investigation provides theoretical guidance for rehabilitative training against osteoporosis.

SAP30 promotes breast tumor progression by bridging the transcriptional corepressor SIN3 complex and MLL1.

SAP30 is a core subunit of the transcriptional corepressor SIN3 complex, but little is known about its role in gene regulation and human cancer. Here, we show that SAP30 was a nonmutational oncoprotein upregulated in more than 50% of human breast tumors and correlated with unfavorable outcomes in patients with breast cancer. In various breast cancer mouse models, we found that SAP30 promoted tumor growth and metastasis through its interaction with SIN3A/3B. Surprisingly, the canonical gene silencing role was not essential for SAP30's tumor-promoting actions. SAP30 enhanced chromatin accessibility and RNA polymerase II occupancy at promoters in breast cancer cells, acting as a coactivator for genes involved in cell motility, angiogenesis, and lymphangiogenesis, thereby driving tumor progression. Notably, SAP30 formed a homodimer with 1 subunit binding to SIN3A and another subunit recruiting MLL1 through specific Phe186/200 residues within its transactivation domain. MLL1 was required for SAP30-mediated transcriptional coactivation and breast tumor progression. Collectively, our findings reveal that SAP30 represents a transcriptional dependency in breast cancer.

Macroscopic negative differential thermal resistance in the overlapping graphene homojunction structure.

As one of the most potential ways to manipulate heat, thermal functional devices have achieved several breakthroughs in recent years, but are still limited to theoretical simulations. One of its theoretical bases is the existence of the negative differential thermal resistance (NDTR). However, most of the existing systems where the phenomenon of NDTR is found are atomic-level systems. In order to realize the macroscopic NDTR and provide effective theoretical guidance and support for the practical realization of thermal functional devices, we construct the overlapping graphene homojunction model, using the negative thermal expansion property of graphene to modify the overlapping area, and thus regulating the heat flow. The COMSOL-MATLAB co-simulation is used to perform calculations through negative feedback loops. It is found that the NDTR phenomenon exists under certain parameter conditions, which can provide new ideas and bring more opportunities for the experimental realization of nonlinear thermal functional devices.

SMRT Sequencing Enables High-Throughput Identification of Novel AAVs from Capsid Shuffling and Directed Evolution.

The use of AAV capsid libraries coupled with various selection strategies has proven to be a remarkable approach for generating novel AAVs with enhanced and desired features. The inability to reliably sequence the complete capsid gene in a high-throughput manner has been the bottleneck of capsid engineering. As a result, many library strategies are confined to localized and modest alterations in the capsid, such as peptide insertions or single variable region (VR) alterations. The caveat of short reads by means of next-generation sequencing (NGS) hinders the diversity of capsid library construction, shifting the field away from whole-capsid modifications. We generated AAV capsid shuffled libraries of naturally occurring AAVs and applied directed evolution in both mice and non-human primates (NHPs), with the goal of yielding AAVs that are compatible across both species for translational applications. We recovered DNA from the tissues of injected animal and used single molecule real-time (SMRT) sequencing to identify variants enriched in the central nervous system (CNS). We provide insights and considerations for variant identification by comparing bulk tissue sequencing to that of isolated nuclei. Our work highlights the potential advantages of whole-capsid engineering, as well as indispensable methodological improvements for the analysis of recovered capsids, including the nuclei-enrichment step and SMRT sequencing.

Endothelial ERα promotes glucose tolerance by enhancing endothelial insulin transport to skeletal muscle.

The estrogen receptor (ER) designated ERα has actions in many cell and tissue types that impact glucose homeostasis. It is unknown if these include mechanisms in endothelial cells, which have the potential to influence relative obesity, and processes in adipose tissue and skeletal muscle that impact glucose control. Here we show that independent of impact on events in adipose tissue, endothelial ERα promotes glucose tolerance by enhancing endothelial insulin transport to skeletal muscle. Endothelial ERα-deficient male mice are glucose intolerant and insulin resistant, and in females the antidiabetogenic actions of estradiol (E2) are absent. The glucose dysregulation is due to impaired skeletal muscle glucose disposal that results from attenuated muscle insulin delivery. Endothelial ERα activation stimulates insulin transcytosis by skeletal muscle microvascular endothelial cells. Mechanistically this involves nuclear ERα-dependent upregulation of vesicular trafficking regulator sorting nexin 5 (SNX5) expression, and PI3 kinase activation that drives plasma membrane recruitment of SNX5. Thus, coupled nuclear and non-nuclear actions of ERα promote endothelial insulin transport to skeletal muscle to foster normal glucose homeostasis.

Engineered DNA molecular machine for ultrasensitive detection of environmental lead pollution.

Dynamic monitoring of environmental Pb2+ is of utmost importance for food safety and personal well-being. Herein, we report a novel, rapid, and practical fluorescence detection platform for Pb2+. The platform comprises two essential components: an engineered DNAzyme probe (EDP) and a responsive functionalized probe (RFP). The EDP demonstrates specific recognition of Pb2+ and the subsequent release of free DNA fragments. The released DNA fragments are then captured using the RFP to form DNA complexes, which undergo multiple cascade amplification reactions involving polymerases and nickases, resulting in the generation of a large number of fluorescence signals. These signals can detect Pb2+ at concentrations as low as 0.114 nmol/L, with a dynamic range spanning from 0.1 nmol/L to 50 nmol/L. Moreover, the platform exhibits excellent sensitivity and selectivity for Pb2+ detection. To further validate its effectiveness, we successfully quantitatively detected lead contamination in water from Chaohu Lake, and the results aligned closely with those obtained using inductively coupled plasma-mass spectrometry (ICP-MS). Moreover, this platform is suitable for detecting Pb2+ in seawater, soil, and fish samples. These findings confirm the suitability of the current detection platform for the dynamic assessment of Pb contamination in ecological environments, thereby contributing to environmental and food safety.

Fucosylated glycoproteins and fucosylated glycolipids play opposing roles in cholera intoxication.

Cholera toxin (CT) is the etiological agent of cholera. Here we report that multiple classes of fucosylated glycoconjugates function in CT binding and intoxication of intestinal epithelial cells. In Colo205 cells, knockout of B3GNT5, the enzyme required for synthesis of lacto- and neolacto-series glycosphingolipids (GSLs), reduces CT binding but sensitizes cells to intoxication. Overexpressing B3GNT5 to generate more fucosylated GSLs confers protection against intoxication, indicating that fucosylated GSLs act as decoy receptors for CT. Knockout (KO) of B3GALT5 causes increased production of fucosylated O-linked and N-linked glycoproteins, and leads to increased CT binding and intoxication. Knockout of B3GNT5 in B3GALT5 KO cells eliminates production of fucosylated GSLs but increases intoxication, identifying fucosylated glycoproteins as functional receptors for CT. These findings provide insight into molecular determinants regulating CT sensitivity of host cells.