Combination Nano-Delivery Systems Remodel the Immunosuppressive Tumor Microenvironment for Metastatic Triple-Negative Breast Cancer Therapy.

Triple-negative breast cancer (TNBC) is an aggressive type of breast cancer for which effective therapies are lacking. Targeted remodeling of the immunosuppressive tumor microenvironment (TME) and activation of the body's immune system to fight tumors with well-designed nanoparticles have emerged as pivotal breakthroughs in tumor treatment. To simultaneously remodel the immunosuppressive TME and trigger immune responses, we designed two potential therapeutic nanodelivery systems to inhibit TNBC. First, the bromodomain-containing protein 4 (BRD4) inhibitor JQ1 and the cyclooxygenase-2 (COX-2) inhibitor celecoxib (CXB) were coloaded into chondroitin sulfate (CS) to obtain CS@JQ1/CXB nanoparticles (NPs). Then, the biomimetic nanosystem MM@P3 was prepared by coating branched polymer poly(ß-amino ester) self-assembled NPs with melittin embedded macrophage membranes (MM). Both in vitro and in vivo, the CS@JQ1/CXB and MM@P3 NPs showed excellent immune activation efficiencies. Combination treatment exhibited synergistic cytotoxicity, antimigration ability, and apoptosis-inducing and immune activation effects on TNBC cells and effectively suppressed tumor growth and metastasis in TNBC tumor-bearing mice by activating the tumor immune response and inhibiting angiogenesis. In summary, this study offers a novel combinatorial immunotherapeutic strategy for the clinical TNBC treatment.

A Bacterial Nanomedicine Combines Photodynamic-Immunotherapy and Chemotherapy for Enhanced Treatment of Oral Squamous Cell Carcinoma.

Bacterial therapy is an emerging hotspot in tumor immunotherapy, which can initiate antitumor immune activation through multiple mechanisms. Porphyromonas gingivalis (Pg), a pathogenic bacterium inhabiting the oral cavity, contains a great deal of pathogen associated molecular patterns that can activate various innate immune cells to promote antitumor immunity. Owing to the presence of protoporphyrin IX (PpIX), Pg is also an excellent photosensitizer for photodynamic therapy (PDT) via the in situ generation of reactive oxygen species. This study reports a bacterial nanomedicine (nmPg) fabricated from Pg through lysozyme degradation, ammonium chloride lysis, and nanoextrusion, which has potent PDT and immune activation performances for oral squamous cell carcinoma (OSCC) treatment. To further promote the tumoricidal efficacy, a commonly used chemotherapeutic drug doxorubicin (DOX) is efficiently encapsulated into nmPg through a simple incubation method. nmPg/DOX thus prepared exhibits significant synergistic effects on inhibiting the growth and metastasis of OSCC both in vitro and in vivo via photodynamic-immunotherapy and chemotherapy. In summary, this work develops a promising bacterial nanomedicine for enhanced treatment of OSCC.

Effects of Terahertz Radiation on the Aggregation of Alzheimer's Aß42 Peptide.

The pathophysiology of Alzheimer's disease is thought to be directly linked to the abnormal aggregation of ß-amyloid (Aß) in the nervous system as a common neurodegenerative disease. Consequently, researchers in many areas are actively looking for factors that affect Aß aggregation. Numerous investigations have demonstrated that, in addition to chemical induction of Aß aggregation, electromagnetic radiation may also affect Aß aggregation. Terahertz waves are an emerging form of non-ionizing radiation that has the potential to affect the secondary bonding networks of biological systems, which in turn could affect the course of biochemical reactions by altering the conformation of biological macromolecules. As the primary radiation target in this investigation, the in vitro modeled Aß42 aggregation system was examined using fluorescence spectrophotometry, supplemented by cellular simulations and transmission electron microscopy, to see how it responded to 3.1 THz radiation in various aggregation phases. The results demonstrated that in the nucleation aggregation stage, 3.1 THz electromagnetic waves promote Aß42 monomer aggregation and that this promoting effect gradually diminishes with the exacerbation of the degree of aggregation. However, by the stage of oligomer aggregation into the original fiber, 3.1 THz electromagnetic waves exhibited an inhibitory effect. This leads us to the conclusion that terahertz radiation has an impact on the stability of the Aß42 secondary structure, which in turn affects how Aß42 molecules are recognized during the aggregation process and causes a seemingly aberrant biochemical response. Molecular dynamics simulation was employed to support the theory based on the aforementioned experimental observations and inferences.

A Cell-Penetrating Peptide Modified Cu2-xSe/Au Nanohybrid with Enhanced Efficacy for Combined Radio-Photothermal Therapy.

Radiotherapy (RT) is one of the main clinical therapeutic strategies against cancer. Currently, multiple radiosensitizers aimed at enhancing X-ray absorption in cancer tissues have been developed, while limitations still exist for their further applications, such as poor cellular uptake, hypoxia-induced radioresistance, and unavoidable damage to adjacent normal body tissues. In order to address these problems, a cell-penetrating TAT peptide (YGRKKRRQRRRC)-modified nanohybrid was constructed by doping high-Z element Au in hollow semiconductor Cu2-xSe nanoparticles for combined RT and photothermal therapy (PTT) against breast cancer. The obtained Cu2-xSe nanoparticles possessed excellent radiosensitizing properties based on their particular band structures, and high photothermal conversion efficiency beneficial for tumor ablation and promoting RT efficacy. Further doping high-Z element Au deposited more high-energy radiation for better radiosensitizing performance. Conjugation of TAT peptides outside the constructed Cu2-xSe/Au nanoparticles facilitated their cellular uptake, thus reducing overdosage-induced side effects. This prepared multifunctional nanohybrid showed powerful suppression effects towards breast cancer, both in vitro and in vivo via integrating enhanced cell penetration and uptake, and combined RT/PTT strategies.

Self-assembled nanoparticles containing photosensitizer and polycationic brush for synergistic photothermal and photodynamic therapy against periodontitis.

BACKGROUND: Periodontitis is a chronic inflammatory disease in oral cavity owing to bacterial infection. Photothermal therapy (PTT) and photodynamic therapy (PDT) have many advantages for antibacterial treatment. As an excellent photosensitizer, indocyanine green (ICG) shows prominent photothermal and photodynamic performances. However, it is difficult to pass through the negatively charged bacterial cell membrane, thus limiting its antibacterial application for periodontitis treatment. RESULTS: In this work, self-assembled nanoparticles containing ICG and polycationic brush were prepared for synergistic PTT and PDT against periodontitis. First, a star-shaped polycationic brush poly(2-(dimethylamino)ethyl methacrylate) (sPDMA) was synthesized via atom transfer radical polymerization (ATRP) of DMA monomer from bromo-substituted ß-cyclodextrin initiator (CD-Br). Next, ICG was assembled with sPDMA to prepare ICG-loaded sPDMA (sPDMA@ICG) nanoparticles (NPs) and the physicochemical properties of these NPs were characterized systematically. In vitro antibacterial effects of sPDMA@ICG NPs were investigated in porphyromonas gingivalis (Pg), one of the recognized periodontitis pathogens. A ligature-induced periodontitis model was established in Sprague-Dawley rats for in vivo evaluation of anti-periodontitis effects of sPDMA@ICG NPs. Benefiting from the unique brush-shaped architecture of sPDMA polycation, sPDMA@ICG NPs significantly promoted the adsorption and penetration of ICG into the bacterial cells and showed excellent PTT and PDT performances. Both in vitro and in vivo, sPDMA@ICG NPs exerted antibacterial and anti-periodontitis actions via synergistic PTT and PDT. CONCLUSIONS: A self-assembled nanosystem containing ICG and polycationic brush has shown promising clinical application for synergistic PTT and PDT against periodontitis.

Design, synthesis and biological evaluation of benzoylacrylic acid shikonin ester derivatives as irreversible dual inhibitors of tubulin and EGFR.

In this study, a series of shikonin derivatives combined with benzoylacrylic had been designed and synthesized, which showed an inhibitory effect on both tubulin and the epidermal growth factor receptor (EGFR). In vitro EGFR and cell growth inhibition assay demonstrated that compound PMMB-317 exhibited the most potent anti-EGFR (IC50 = 22.7 nM) and anti-proliferation activity (IC50 = 4.37 µM) against A549 cell line, which was comparable to that of Afatinib (EGFR, IC50 = 15.4 nM; A549, IC50 = 6.32 µM). Our results on mechanism research suggested that, PMMB-317 could induce the apoptosis of A549 cells in a dose- and time-dependent manner, along with decrease in mitochondrial membrane potential (MMP), production of ROS and alterations in apoptosis-related protein levels. Also, PMMB-317 could arrest cell cycle at G2/M phase to induce cell apoptosis, and inhibit the EGFR activity through blocking the signal transduction downstream of the mitogen-activated protein MAPK pathway and the anti-apoptotic kinase AKT pathway; typically, such results were comparable to those of afatinib. In addition, PMMB-317 could suppress A549 cell migration through the Wnt/ß-catenin signaling pathway in a dose-dependent manner. Additionally, molecular docking simulation revealed that, PMMB-317 could simultaneously combine with EGFR protein (5HG8) and tubulin (1SA0) through various forces. Moreover, 3D-QSAR study was also carried out, which could optimize our compound through the structure-activity relationship analysis. Furthermore, the in vitro and in vivo results had collectively confirmed that PMMB-317 might serve as a promising lead compound to further develop the potential therapeutic anticancer agents.

pH and redox dual-responsive nanoparticles based on disulfide-containing poly(ß-amino ester) for combining chemotherapy and COX-2 inhibitor to overcome drug resistance in breast cancer.

BACKGROUND: Multidrug resistance (MDR) generally leads to breast cancer treatment failure. The most common mechanism of MDR is the overexpression of ATP-binding cassette (ABC) efflux transporters such as P-glycoprotein (P-gp) that reduce the intracellular accumulation of various chemotherapeutic agents. Celecoxib (CXB), a selective COX-2 inhibitor, can dramatically enhance the cytotoxicity of doxorubicin (DOX) in breast cancer cells overexpressing P-gp. Thus it can be seen that the combination of DOX and CXB maybe obtain synergistic effects against breast cancer by overcoming drug resistance. RESULTS: In this study, we designed a pH and redox dual-responsive nanocarrier system to combine synergistic effects of DOX and CXB against drug resistant breast cancer. This nanocarrier system denoted as HPPDC nanoparticles showed good in vitro stability and significantly accelerated drug releases under the acidic and redox conditions. In drug-resistant human breast cancer MCF-7/ADR cells, HPPDC nanoparticles significantly enhanced the cellular uptake of DOX through the endocytosis mediated by CD44/HA specific binding and the down-regulated P-gp expression induced by COX-2 inhibition, and thus notably increased the cytotoxicity and apoptosis-inducing activity of DOX. In MCF-7/ADR tumor-bearing nude mice, HPPDC nanoparticles showed excellent tumor-targeting ability, remarkably enhanced tumor chemosensitivity and reduced COX-2 and P-gp expressions in tumor tissues. CONCLUSION: All results demonstrated that HPPDC nanoparticles can efficiently overcome drug resistance in breast cancer both in vitro and in vivo by combining chemotherapy and COX-2 inhibitor. In a summary, HPPDC nanoparticles show a great potential for combination treatment of drug resistant breast cancer.

Nanoparticles based on disulfide-containing poly(ß-amino ester) and zwitterionic fluorocarbon surfactant as a redox-responsive drug carrier for brain tumor treatment.

Malignant brain tumors are often characterized by rapid growth, high invasiveness and poor prognosis. Current methods for brain tumor treatment are dramatically limited because of their inability to cross the blood-brain barrier (BBB) and enter the tumor cells. In this study, we prepared redox-responsive nanoparticles based on disulfide-containing poly(ß-amino ester) (ssPBAE) and a zwitterionic fluorocarbon surfactant (Intechem-02) that has a carboxybetaine moiety in molecular structure, and preliminarily evaluated their potential as a drug carrier for brain tumor treatment. These nanoparticles, named as ssPBAEI, had a regular spherical shape and a small size below 50 nm with a relative narrow distribution. Doxorubicin (DOX), as a model chemotherapeutic drug, was efficiently encapsulated into ssPBAEI nanoparticles with a loading content of 25.4%. DOX-loaded ssPBAEI nanoparticles (ssPBAEI/DOX) showed significant redox-responsive in vitro release property and successfully carried DOX across a BBB model, monolayer of human brain capillary endothelial hCMEC/D3 cells. In human glioma LN229 cells, ssPBAEI/DOX nanoparticles were efficiently internalized and DOX was successfully released afterwards, thus significantly inhibited cell growth and induced cell apoptosis. In summary, this nanoparticle system based on ssPBAE and Intechem-02 showed a great potential as a drug carrier for brain tumor treatment.

pH- and redox-responsive nanoparticles composed of charge-reversible pullulan-based shells and disulfide-containing poly(ß-amino ester) cores for co-delivery of a gene and chemotherapeutic agent.

A novel pH- and redox-responsive nanoparticle system was designed based on a charge-reversible pullulan derivative (CAPL) and disulfide-containing poly(ß-amino ester) (ssPBAE) for the co-delivery of a gene and chemotherapeutic agent targeting hepatoma. The end-alkene groups of ssPBAE were reacted with diethylenetriamine to form amino-modified ssPBAE (NH-ssPBAE). Methotrexate (MTX), a chemotherapy agent, was then conjugated to NH-ssPBAE via an amide bond to obtain the polymeric prodrug ssPBAE-MTX. ssPBAE-MTX exhibited a good capability for condensing genes, including plasmid DNA (pDNA) and tetramethyl rhodamine-labeled DNA (TAMRA-DNA), and almost completely condensed pDNA at the weight ratio of 5/1 to form spherical nanocomplexes with a uniform size. In a D,L-dithiothreitol solution, the ssPBAE-MTX/pDNA nanocomplexes showed rapid release of pDNA and MTX, indicating their redox-responsive capability. CAPL, a pullulan derivative containing ß-carboxylic amide bond, was efficiently coated on the surfaces of ssPBAE-MTX/pDNA nanocomplexes to form polysaccharide shells, thus realizing co-loading of the gene and chemotherapeutic agent. CAPL/ssPBAE-MTX/pDNA nanoparticles displayed an obvious pH-responsive charge reversal ability due to the rupture of the ß-carboxylic amide bond under the weakly acidic condition. In human hepatoma HepG2 cells, CAPL/ssPBAE-MTX/TAMRA-DNA nanoparticles were efficiently internalized via endocytosis and successfully escaped from the endo/lysosomes into the cytoplasm, and CAPL/ssPBAE-MTX/pDNA nanoparticles remarkably inhibited the cell growth. In summary, this nanoparticle system based on CAPL and ssPBAE showed great potential for combined gene/chemotherapy on hepatomas.

Functionalized Graphene Oxide with Hepatocyte Targeting as Anti-Tumor Drug and Gene Intracellular Transporters.

In order to realize the hepatocyte-specific targeted delivery of anti-tumor drug and gene, lactosylated chitosan oligosaccharide (LCO) functionalized graphene oxides (GO-LCO) containing quaternary ammonium groups (GO-LCO+) were prepared. The formation and composition of GO-LCO+ were confirmed by FTIR, AFM, TGA and zeta-potential. The in vitro cells uptakes of this functionalized GO were investigated and the results showed that GO-LCO+ can deliver fluorescein FAM-labeled DNA sequence (FAM-DNA) into human hepatic carcinoma cells (QGY-7703) with higher efficiency than positively charged chitosan oligosaccharide (CO) functionalized graphene oxides (GO-CO+) without Lactose acid modification. The loading efficiency of doxorubicin chloride (Dox) on GO-LCO+ with 477 µg/mg was obtained at the initial Dox concentration of 0.45 mg/ml and release of Dox on GO-LCO+ showed strong pH dependence. The toxicity of GO-LCO+ before and after loading with Dox toward QGY-7703 cells was further investigated. Our results suggest the functionalized GO to be used as a nanocarrier for hepatocyte targeted co-delivery of anti-tumor drugs and genes with low cytotoxicity, promising for future applications in anticancer drug and gene combined therapy.

Association between VANGL1 gene polymorphisms and neural tube defects.

Neural tube defects (NTDs) are common, severe congenital malformations. The association between single nucleotide polymorphisms of the VANGL1 gene and NTDs in a Han population of Northern China was principally studied. Missense single nucleotide polymorphisms (rs4839469 c.346G > A p.Ala116Thr and rs34059106 c.1040A > C p.Glu347Ala) of the VANGL1 gene were analyzed by polymerase chain reaction (PCR) and sequencing methods in 135 NTD cases and 135 normal controls. Genotype and allele frequency distribution was calculated, and the spatial structure of the protein was predicted. The results showed that the VANGL1 gene sequence at the rs4839469 locus exhibited Ala116Thr and Ala116Pro polymorphisms, and allele and genotype distributions were significantly different (p = 0.036 and 0.010) between the case and control group. Genotype GC was newly discovered, and its odds ratio value versus GG genotype was 10.241; the α helix fragment of the Ala116Pro mutant was significantly shortened compared with wild type. The rs34059106 site showed alleles of A and did not display C alleles in the two groups. Therefore, the rs4839469 allele of VANGL1 was obviously associated with NTDs. And genotype GC increased the risk of NTDs, changes in the three-dimensional protein structure may have impacted its biological functions, and the rs34059106 polymorphism had no significant correlation with NTDs.

N-lauroyl chitosan surface-modified PLGA nanoparticles as carrier for adriamycin to overcome cancer drug resistance.

N-lauroyl chitosan (NLCS) conjugates with different degrees of substitution (DS) of lauroyl group were synthesized and used to prepare surface modified poly(lactic-co-glycolic) acid (NLCS-PLGA) nanoparticles via hydrophobic interaction and ionic bond force. NLCS-PLGA nanoparticles had spherical shape with shell-core structure and exhibited the smallest size and narrowest size distribution when DS of lauroyl group of NLCS was 8.5%. Adriamycin (ADR), as a model antitumor drug, was loaded into NLCS-PLGA nanoaprticles and its initial burst release from PLGA nanoparticles was significantly reduced. MTT assay showed that NLCS-2-PLGA nanoaprticles evidently enhanced cytotoxicity of ADR against drug-resistant breast cancer MCF-7/ADR cells, both compared to free ADR and ADR-loaded PLGA nanoparticles. Moreover, cell-live images showed that the cellular uptake and nuclear location of ADR in MCF-7/ADR cells were significantly enhanced by loading of NLCS-2-PLGA nanoparticles. In conclusion, this novel carrier of anticancer drugs has the potential to overcome drug resistance in cancer cells.

Delivery of Interferon ß-Encoding Plasmid via Lipid Nanoparticle Restores Interferon ß Expression to Enhance Antitumor Immunity in Colon Cancer.

Type I interferon (IFN-I) plays a critical role in host cancer immunosurveillance, but its expression is often impaired in the tumor microenvironment. We aimed at testing the hypothesis that cationic lipid nanoparticle delivery of interferon ß (IFNß)-encoding plasmid to tumors is effective in restoring IFNß expression to suppress tumor immune evasion. We determined that IFN-I function in tumor suppression depends on the host immune cells. IFN-I activates the expression of Cxcl9 and Cxcl10 to enhance T cell tumor infiltration. RNA-Seq detected a low level of IFNα13 and IFNß in colon tumor tissue. scRNA-Seq revealed that IFNß is expressed in immune cell subsets in non-neoplastic human tissues and to a lesser degree in human colon tumor tissues. Forced expression of IFNα13 and IFNß in colon tumor cells up-regulates major histocompatibility complex I (MHC I) expression and suppresses colon tumor growth in vivo. In human cancer patients, IFNß expression is positively correlated with human leukocyte antigen (HLA) expression, and IFN-I signaling activation correlates with the patient response to PD-1 blockade immunotherapy. To translate this finding to colon cancer immunotherapy, we formulated a 1,2-dioleoyl-3-trimethylammonium propane (DOTAP)-cholesterol-encapsulated IFNß-encoding plasmid (IFNBCOL01). IFNBCOL01 transfects colon tumor cells to express IFNß to increase the level of MHC I expression. IFNBCOL01 therapy transfects tumor cells and tumor-infiltrating immune cells to produce IFNß to activate MHC I and granzyme B expression and inhibits colon tumor growth in mice. Our data determine that lipid nanoparticle delivery of IFNß-encoding plasmid DNA enhances tumor immunogenicity and T cell effector function to suppress colon tumor growth in vivo.

Homologous-targeting biomimetic nanoparticles co-loaded with melittin and a photosensitizer for the combination therapy of triple negative breast cancer.

Melittin (Mel) is considered a promising candidate drug for the treatment of triple negative breast cancer (TNBC) due to its various antitumor effects. However, its clinical application is hampered by notable limitations, including hemolytic activity, rapid clearance, and a lack of tumor selectivity. Here, we designed novel biomimetic nanoparticles based on homologous tumor cell membranes and poly(lactic-co-glycolic acid) (PLGA)/poly(beta-aminoester) (PBAE), denoted MDM@TPP, which efficiently coloaded the cytolytic peptide Mel and the photosensitizer mTHPC. Both in vitro and in vivo, the MDM@TPP nanoparticles effectively mitigated the acute toxicity of melittin and exhibited strong TNBC targeting ability due to the homologous targeting effect of the tumor cell membrane. Under laser irradiation, the MDM@TPP nanoparticles showed excellent photodynamic performance and thus accelerated the release of Mel by disrupting cell membrane integrity. Moreover, Mel combined with photodynamic therapy (PDT) can synergistically kill tumor cells and induce significant immunogenic cell death, thereby stimulating the maturation of dendritic cells (DCs). In 4T1 tumor-bearing mice, MDM@TPP nanoparticles effectively inhibited the growth and metastasis of primary tumors and finally prevented tumor recurrence by improving the immune response.

A ß-Carboline Derivate PAD4 Inhibitor Reshapes Neutrophil Phenotype and Improves the Tumor Immune Microenvironment against Triple-Negative Breast Cancer.

Triple-negative breast cancer is a highly aggressive and heterogeneous breast cancer subtype characterized by early metastasis, poor prognosis, and high recurrence. Targeting histone citrullination-mediated chromatin dysregulation to induce epigenetic alterations shows great promise in TNBC therapy. We report the synthesis, optimization, and evaluation of a novel series of ß-carboline-derived peptidyl arginine deiminase 4 inhibitors that exhibited potent inhibition of TNBC cell proliferation. The most outstanding PAD4 inhibitor, compound 28, hindered the PAD4-H3cit-NET signaling pathway and inhibited the growth of solid tumors and pulmonary metastatic nodules in the 4T1 in situ mouse model. Furthermore, 28 improved the tumor immune microenvironment by reshaping neutrophil phenotype, upregulating the proportions of dendritic cells and M1 macrophages, and reducing the amount of myeloid-derived suppressor cells. In conclusion, our work offered 28 as an efficacious PAD4 inhibitor that exerts a combination of conventional chemotherapy and immune-boosting effects, which represents a potential therapy strategy for TNBC.

Water soluble fluorescence quantum dot probe labeling liver cancer cells.

Water soluble quantum dots (QDs) have been prepared by hydrothermal method and characterized by ultraviolet irradiation, XRD, TEM, UV-Vis absorption spectrometer and fluorescence spectrometer. Then the QD-antibody-AFP probes (QD-Ab-AFP) were synthesized by chemical process and specifically labeled AFP antigen in PLC/PRF/5 liver cancer cells. The results showed that the QDs were cubic structure and had excellent optical properties. Moreover, the QD-Ab-AFP with good stability could specifically label liver cancer cells. This work provides strong foundation for further studying and developing new approach to detect liver cancer at early stage.

ORCCA: Optimal Randomized Canonical Correlation Analysis.

Random features approach has been widely used for kernel approximation in large-scale machine learning. A number of recent studies have explored data-dependent sampling of features, modifying the stochastic oracle from which random features are sampled. While proposed techniques in this realm improve the approximation, their suitability is often verified on a single learning task. In this article, we propose a task-specific scoring rule for selecting random features, which can be employed for different applications with some adjustments. We restrict our attention to canonical correlation analysis (CCA) and provide a novel, principled guide for finding the score function maximizing the canonical correlations. We prove that this method, called optimal randomized CCA (ORCCA), can outperform (in expectation) the corresponding kernel CCA with a default kernel. Numerical experiments verify that ORCCA is significantly superior to other approximation techniques in the CCA task.

TAKDE: Temporal Adaptive Kernel Density Estimator for Real-Time Dynamic Density Estimation.

Real-time density estimation is ubiquitous in many applications, including computer vision and signal processing. Kernel density estimation is arguably one of the most commonly used density estimation techniques, and the use of "sliding window" mechanism adapts kernel density estimators to dynamic processes. In this article, we derive the asymptotic mean integrated squared error (AMISE) upper bound for the "sliding window" kernel density estimator. This upper bound provides a principled guide to devise a novel estimator, which we name the temporal adaptive kernel density estimator (TAKDE). Compared to heuristic approaches for "sliding window" kernel density estimator, TAKDE is theoretically optimal in terms of the worst-case AMISE. We provide numerical experiments using synthetic and real-world datasets, showing that TAKDE outperforms other state-of-the-art dynamic density estimators (including those outside of kernel family). In particular, TAKDE achieves a superior test log-likelihood with a smaller run-time.

Chloroplast proteostasis: A story of birth, life, and death.

Protein homeostasis (proteostasis) is a dynamic balance of protein synthesis and degradation. Because of the endosymbiotic origin of chloroplasts and the massive transfer of their genetic information to the nucleus of the host cell, many protein complexes in the chloroplasts are constituted from subunits encoded by both genomes. Hence, the proper function of chloroplasts relies on the coordinated expression of chloroplast- and nucleus-encoded genes. The biogenesis and maintenance of chloroplast proteostasis are dependent on synthesis of chloroplast-encoded proteins, import of nucleus-encoded chloroplast proteins from the cytosol, and clearance of damaged or otherwise undesired "old" proteins. This review focuses on the regulation of chloroplast proteostasis, its interaction with proteostasis of the cytosol, and its retrograde control over nuclear gene expression. We also discuss significant issues and perspectives for future studies and potential applications for improving the photosynthetic performance and stress tolerance of crops.

Oxyhemoglobin-Based Nanophotosensitizer for Specific and Synergistic Photothermal and Photodynamic Therapies against Porphyromonas gingivalis Oral Infection.

Photothermal therapy (PTT) and photodynamic therapy (PDT) are emerging alternative antibacterial approaches. However, due to the lack of selectivity of photosensitizers for pathogenic bacteria, these methods often show more or less different degrees of in vivo toxicity. Moreover, it is difficult for PDT to exert effective antibacterial effects against anaerobic infections due to the oxygen deficiency. As one of the major anaerobic pathogens in oral infections, Porphyromonas gingivalis (P. gingivalis) acquires iron and porphyrin mainly from hemoglobin in the host. Hence, we developed a nanophotosensitizer named as oxyHb@IR820 through stable complexation between oxyhemoglobin and IR820, which is a photosensitizer possessing both PTT and PDT performance, for fighting P. gingivalis oral infection specifically and efficiently. Owing to hydrophobic interaction, oxyHb@IR820 had much stronger photoabsorption at 808 nm than free IR820, and thus exhibited significantly enhanced photothermal conversion efficiency. As an oxygen donor, oxyHb played an important role in enhancing the photodynamic efficiency of oxyHb@IR820. More importantly, oxyHb@IR820 showed efficient and specific uptake in P. gingivalis and exerted synergistic PTT/PDT performance against P. gingivalis and oral infection in golden hamsters. In summary, this study provides an efficient strategy for delivering photosensitizers specifically to P. gingivalis and augmenting antibacterial PDT against anaerobic infections.