Regulation of candidalysin underlies Candida albicans persistence in intravascular catheters by modulating NETosis.

Candida albicans is a leading cause of intravascular catheter-related infections. The capacity for biofilm formation has been proposed to contribute to the persistence of this fungal pathogen on catheter surfaces. While efforts have been devoted to identifying microbial factors that modulate C. albicans biofilm formation in vitro, our understanding of the host factors that may shape C. albicans persistence in intravascular catheters is lacking. Here, we used multiphoton microscopy to characterize biofilms in intravascular catheters removed from candidiasis patients. We demonstrated that, NETosis, a type of neutrophil cell death with antimicrobial activity, was implicated in the interaction of immune cells with C. albicans in the catheters. The catheter isolates exhibited reduced filamentation and candidalysin gene expression, specifically in the total parenteral nutrition culture environment. Furthermore, we showed that the ablation of candidalysin expression in C. albicans reduced NETosis and conferred resistance to neutrophil-mediated fungal biofilm elimination. Our findings illustrate the role of neutrophil NETosis in modulating C. albicans biofilm persistence in an intravascular catheter, highlighting that C. albicans can benefit from reduced virulence expression to promote its persistence in an intravascular catheter.

Phototherapy for age-related brain diseases: Challenges, successes and future.

Brain diseases present a significant obstacle to both global health and economic progress, owing to their elusive pathogenesis and the limited effectiveness of pharmaceutical interventions. Phototherapy has emerged as a promising non-invasive therapeutic modality for addressing age-related brain disorders, including stroke, Alzheimer's disease (AD), and Parkinson's disease (PD), among others. This review examines the recent progressions in phototherapeutic interventions. Firstly, the article elucidates the various wavelengths of visible light that possess the capability to penetrate the skin and skull, as well as the pathways of light stimulation, encompassing the eyes, skin, veins, and skull. Secondly, it deliberates on the molecular mechanisms of visible light on photosensitive proteins, within the context of brain disorders and other molecular pathways of light modulation. Lastly, the practical application of phototherapy in diverse clinical neurological disorders is indicated. Additionally, this review presents novel approaches that combine phototherapy and pharmacological interventions. Moreover, it outlines the limitations of phototherapeutics and proposes innovative strategies to improve the treatment of cerebral disorders.

PEGylated-liposomal astaxanthin ameliorates Aß neurotoxicity and Alzheimer-related phenotypes by scavenging formaldehyde.

Alzheimer's disease (AD), which is a prevailing type of dementia, presents a significant global health concern. The current therapies do not meet clinical expectations. Amyloid-beta (Aß) has been found to induce endogenous formaldehyde (FA) accumulation by inactivating FA dehydrogenase (FDH); in turn, excessive FA triggers Aß aggregation that eventually leads to AD onset. Hence, scavenging FA by astaxanthin (ATX, a strong exogenous antioxidant) may be pursued as a promising disease-modifying approach. Here, we report that liposomal nanoparticles coupled with PEG (PEG-ATX@NPs) could enhance water-solubility of ATX and alleviate cognitive impairments by scavenging FA and reducing Aß deposition. To enable drug delivery to the brain, liposomes were used to encapsulate ATX and then coupled with PEG, which produced liposomal nanoparticles (PEGATX@NPs) with a diameter of <100 nm. The PEG-ATX@NPs reduced Aß neurotoxicity by both degrading FA and reducing FA-induced Aß assembly in vitro. Intraperitoneal administration of PEG-ATX@NPs in APPswe/PS1dE9 mice (APP/PS1, a familial model of AD), not only decreased the levels of brain FA and malondialdehyde (MDA, a typical product of oxidative stress), but also attenuated both intracellular Aß oligomerization and extracellular Aß-related senile plaque (SP) formation. These pathological changes were accompanied by rescued ability of spatial learning and memory. Collectively, PEG-ATX@NPs improved the water-solubility, bioavailability, and effectiveness of ATX. Thus, it has the potential to be developed as a safe and effective strategy for treating AD.

Osteoporosis and osteoarthritis: a bi-directional Mendelian randomization study.

OBJECTIVE: To investigate the causal relationship between low bone mineral density (BMD) and osteoarthritis (OA) using Mendelian randomization (MR) design. METHODS: Two-sample bi-directional MR analyses were performed using summary-level information on OA traits from UK Biobank and arcOGEN. Sensitivity analyses including MR-Egger, simple median, weighted median, MR pleiotropy residual sum, and outlier approaches were utilized in conjunction with inverse variance weighting (IVW). Gene ontology (GO) enrichment analyses and expression quantitative trait locus (eQTL) colocalization analyses were used to investigate the potential mechanism and shared genes between osteoporosis (OP) and OA. RESULTS: The IVW method revealed that genetically predicted low femoral neck BMD was significantly linked with hip (ß = 0.105, 95% CI: 0.023-0.188) and knee OA (ß = 0.117, 95% CI: 0.049-0.184), but not with other site-specific OA. Genetically predicted low lumber spine BMD was significantly associated with OA at any sites (ß = 0.048, 95% CI: 0.011-0.085), knee OA (ß = 0.101, 95% CI: 0.045-0.156), and hip OA (ß = 0.150, 95% CI: 0.077-0.224). Only hip OA was significantly linked with genetically predicted reduced total bone BMD (ß = 0.092, 95% CI: 0.010-0.174). In the reverse MR analyses, no evidence for a causal effect of OA on BMD was found. GO enrichment analysis and eQTL analysis illustrated that DDN and SMAD-3 were the most prominent co-located genes. CONCLUSIONS: These findings suggested that OP may be causally linked to an increased risk of OA, indicating that measures to raise BMD may be effective in preventing OA. More research is required to determine the underlying processes via which OP causes OA.

Genomic Surveillance of Listeria monocytogenes in Taiwan, 2014 to 2019.

Listeria monocytogenes is a life-threatening foodborne pathogen. Here, we report the genomic characterization of a nationwide dataset of 411 clinical and 82 food isolates collected in Taiwan between 2014 and 2019. The observed incidence of listeriosis increased from 0.83 to 7 cases per million population upon implementation of mandatory notification in 2018. Pregnancy-associated cases accounted for 2.8% of human listeriosis and all-cause 7-day mortality was of 11.9% in nonmaternal-neonatal listeriosis. L. monocytogenes was isolated from 90% of raw pork and 34% of chicken products collected in supermarkets. Sublineages SL87, SL5, and SL378 accounted for the majority (65%) of clinical cases. SL87 and SL378 were also predominant (57%) in food products. Five cgMLST clusters accounted for 57% clinical cases, suggesting unnoticed outbreaks spanning up to 6 years. Mandatory notification allowed identifying the magnitude of listeriosis in Taiwan. Continuous real-time genomic surveillance will allow reducing contaminating sources and disease burden. IMPORTANCE Understanding the phylogenetic relationship between clinical and food isolates is important to identify the transmission routes of foodborne diseases. Here, we performed a nationwide study between 2014 and 2019 of both clinical and food Listeria monocytogenes isolates and sequenced their genomes. We show a 9-fold increase in listeriosis reporting upon implementation of mandatory notification. We found that sublineages SL87 and SL378 predominated among both clinical (50%) and food (57%) isolates, and identified five cgMLST clusters accounting for 57% of clinical cases, suggestive of potential protracted sources of contamination over up to 6 years in Taiwan. These findings highlight that mandatory declaration is critical in identifying the burden of listeriosis, and the importance of genome sequencing for a detailed characterization of the pathogenic L. monocytogenes genotypes circulating in Asia.

New insight into brain disease therapy: nanomedicines-crossing blood-brain barrier and extracellular space for drug delivery.

INTRODUCTION: Brain diseases including brain tumor, Alzheimer's disease, Parkinson's disease, etc. are difficult to treat. The blood-brain barrier (BBB) is a major obstacle for drug delivery into the brain. Although nano-package and receptor-mediated delivery of nanomedicine markedly increases BBB penetration, it yet did not extensively improve clinical cure rate. Recently, brain extracellular space (ECS) and interstitial fluid (ISF) drainage in ECS have been found to determine whether a drug dissolved in ISF can reach its target cells. Notably, an increase in tortuosity of ECS associated with slower ISF drainage induced by the accumulated harmful substances, such as: amyloid-beta (Aß), α-synuclein, and metabolic wastes, causes drug delivery failure. AREAS COVERED: The methods of nano-package and receptor-mediated drug delivery and the penetration efficacy of nanomedicines across BBB and ECS are assessed. EXPERT OPINION: Invasive delivering drug via ECS and noninvasive near-infrared photo-sensitive nanomedicines may provide a promising benefit to patients with brain disease.

The identification and functional analysis of CD8+PD-1+CD161+ T cells in hepatocellular carcinoma.

Immunotherapy is a powerful therapeutic strategy for end-stage hepatocellular carcinoma (HCC). It is well known that T cells, including CD8+PD-1+ T cells, play important roles involving tumor development. However, their underlying phenotypic and functional differences of T cell subsets remain unclear. We constructed single-cell immune contexture involving approximate 20,000,000 immune cells from 15 pairs of HCC tumor and non-tumor adjacent tissues and 10 blood samples (including five of HCCs and five of healthy controls) by mass cytometry. scRNA-seq and functional analysis were applied to explore the function of cells. Multi-color fluorescence staining and tissue micro-arrays were used to identify the pathological distribution of CD8+PD-1+CD161 +/- T cells and their potential clinical implication. The differential distribution of CD8+ T cells subgroups was identified in tumor and non-tumor adjacent tissues. The proportion of CD8+PD1+CD161+ T cells was significantly decreased in tumor tissues, whereas the ratio of CD8+PD1+CD161- T cells was much lower in non-tumor adjacent tissues. Diffusion analysis revealed the distinct evolutionary trajectory of CD8+PD1+CD161+ and CD8+PD1+CD161- T cells. scRNA-seq and functional study further revealed the stronger immune activity of CD8+PD1+CD161+ T cells independent of MHC class II molecules expression. Interestingly, a similar change in the ratio of CD8+CD161+/ CD8+CD161- T cells was also found in peripheral blood samples collected from HCC cases, indicating their potential usage clinically. We here identified different distribution, function, and trajectory of CD8+PD-1+CD161+ and CD8+PD-1+CD161- T cells in tumor lesions, which provided new insights for the heterogeneity of immune environment in HCCs and also shed light on the potential target for immunotherapy.

Trajectory and Functional Analysis of PD-1high CD4+CD8+ T Cells in Hepatocellular Carcinoma by Single-Cell Cytometry and Transcriptome Sequencing.

The spatial heterogeneity of immune microenvironment in hepatocellular carcinoma (HCC) remains elusive. Here, a single-cell study involving 17 432 600 immune cells of 39 matched HCC (T), nontumor (N), and leading-edge (L) specimens by mass cytometry is conducted. The tumor-associated CD4/CD8 double-positive T (DPT) cells are found enriched in L regions with synergetic expression of PD-1/HLA-DR/ICOS/CD45RO and exhibit a higher level of IFN-γ, TNF-α, and PD-1 upon stimulation. The enrichment of DPT and PD-1+DPT in L regions indicates favorable prognosis. These tumor-associated DPT cells with similar phenotype are also verified in other tumors and HCC animal models. Single-cell RNA-seq further characterizes the molecular features of DPT cells and uncovers 11 clusters with different cytotoxicity, exhaustion, and activation scores. TCR-based trajectory analysis reveals that tumor-associated DPT clusters share separated ancestries with local CD4+ or CD8+SPT cells rather than CD3+PBMC cells. TCR clones with frequency above 10 are mainly found coexisting in DPT and CD8+SPT cells. Specifically, PD-1highDPT cluster (TDPT_10) shares the same ancestry with exhausted CD8+SPT cluster (TCD8T_2) and shows higher expression similarity and closer pathological location to PD-1+CD8+ than PD-1+CD4+T cells. Together, this study systematically characterizes the unique distribution of PD-1+DPTs in HCC and puts forward new insights for the function and origin of tumor-associated DPT cells.

Fabrication and characterization of TGF-ß1-loaded electrospun poly (lactic-co-glycolic acid) core-sheath sutures.

It is difficult for traditional sutures, which are usually braided by microfibers, to load drugs or growth factors. To develop a novel species of suture, in this study, a core-sheath yarn was fabricated by surrounding Poly (lactic-co-glycolic acid) (PLGA) microfibers with electrospun PLGA nanofibers using a custom electrospinning equipment with two needles and a rotating funnel. The resulting yarn shows enough mechanical strength to be used as sutures. The capillary action, which is caused by the structure of the core-sheath yarn, enabled the PLGA yarn to easily absorb a growth factor. Thus TGF-ß1 was loaded to the core-sheath yarn ensuring that the suture has a tissue repairing function. Human umbilical vein endothelial cells grew faster on TGF-ß1 loaded core-sheath yarn than on the core-sheath yarn without growth factor. This core-sheath yarn fabrication method has the potential to be used in the development of functional sutures.

Evaluation of the potential of kartogenin encapsulated poly(L-lactic acid-co-caprolactone)/collagen nanofibers for tracheal cartilage regeneration.

Tracheal stenosis is one of major challenging issues in clinical medicine because of the poor intrinsic ability of tracheal cartilage for repair. Tissue engineering provides an alternative method for the treatment of tracheal defects by generating replacement tracheal structures. In this study, we fabricated coaxial electrospun fibers using poly(L-lactic acid-co-caprolactone) and collagen solution as shell fluid and kartogenin solution as core fluid. Scanning electron microscope and transmission electron microscope images demonstrated that nanofibers had uniform and smooth structure. The kartogenin released from the scaffolds in a sustained and stable manner for about 2 months. The bioactivity of released kartogenin was evaluated by its effect on maintain the synthesis of type II collagen and glycosaminoglycans by chondrocytes. The proliferation and morphology analyses of mesenchymal stems cells derived from bone marrow of rabbits indicated the good biocompatibility of the fabricated nanofibrous scaffold. Meanwhile, the chondrogenic differentiation of bone marrow mesenchymal stem cells cultured on core-shell nanofibrous scaffold was evaluated by real-time polymerase chain reaction. The results suggested that the core-shell nanofibrous scaffold with kartogenin could promote the chondrogenic differentiation ability of bone marrow mesenchymal stem cells. Overall, the core-shell nanofibrous scaffold could be an effective delivery system for kartogenin and served as a promising tissue engineered scaffold for tracheal cartilage regeneration.