Multimodal phototherapy agents target lipid droplets for near-infrared imaging-guided type I photodynamic/photothermal therapy.

The construction and optimization of a single phototherapeutic agent with photoluminescence, type I photodynamic therapy (PDT), and photothermal therapy (PTT) functions remain challenging. In this study, we aimed to design and synthesize four donor-acceptor (D-A) type aggregation-induced emission molecules: PSI, TPSI, PSSI, and TPSSI. We employed phenothiazine as an electron donor and 1,3-bis(dicyanomethylidene)indan as a strong electron acceptor in the synthesis process. Among them, TPSSI exhibited efficient type I reactive oxygen species generation, high photothermal conversion efficiency (45.44 %), and near-infrared emission. These observations can be attributed to the introduction of a triphenylamine electron donor group and a thiophene unit, which resulted in increased D-A strengths, a reduced singlet-triplet energy gap, and increased free intramolecular motion. TPSSI was loaded into bovine serum albumin to prepare biocompatible TPSSI nanoparticles (NPs). Our results have indicated that TPSSI NPs can target lipid droplets with negligible dark toxicity and can efficiently generate O2•- in hypoxic tumor environments. Moreover, TPSSI NPs selectively targeted 4T1 tumor tissues and exhibited a good PDT-PTT synergistic effect in vitro and in vivo. We believe that the successful preparation of multifunctional phototherapeutic agents will promote the development of efficient tumor diagnosis and treatment technologies. STATEMENT OF SIGNIFICANCE: The construction of a single phototherapeutic agent with photoluminescence, type I photodynamic therapy, and photothermal therapy functions, and its optimization remain challenging. In this study, we construct four donor-acceptor aggregation-induced emission molecules using phenothiazine as an electron donor and 1,3-Bis(dicyanomethylidene)indan as a strong electron acceptor. By optimizing the molecular structure, an integrated phototherapy agent with fluorescence imaging ability and high photodynamic / photothermal therapy performance was prepared. We believe that the successful preparation of multifunctional phototherapeutic agents will promote the development of efficient tumor diagnosis and treatment technology.

Nanorod-like Bimetallic Oxide for Enhancing the Performance of Supercapacitor Electrodes.

Supercapacitors are widely used in many fields owing to their advantages, such as high power, good cycle performance, and fast charging speed. Among the many metal-oxide cathode materials reported for supercapacitors, NiMoO4 is currently the most promising electrode material for high-specific-energy supercapacitors. We have employed a rational design approach to create a nanorod-like NiMoO4 structure, which serves as a conductive scaffold for supercapacitors; the straightforward layout has led to outstanding results, with nanorod-shaped NiMoO4 exhibiting a remarkable capacity of 424.8 F g-1 at 1 A g-1 and an impressive stability of 80.2% capacity preservation even after 3500 cycles, which surpasses those of the majority of previously reported NiMoO4 materials. NiMoO4//AC supercapacitors demonstrate a remarkable energy density of 46.31 W h kg-1 and a power density of 0.75 kW kg-1. This synthesis strategy provides a facile method for the fabrication of bimetallic oxide materials for high-performance supercapacitors.

The antiviral effects of TRIM23 and TRIM32 proteins in rainbow trout (Oncorhynchus mykiss).

TRIM proteins play a crucial antiviral effector role in the innate immune system of vertebrates. In this study, we found that TRIM proteins exhibited the highest expression levels in immune organs such as spleen and kidney during IHNV infection in rainbow trout, meanwhile, we successfully amplified TRIM23 and TRIM32 from diseased rainbow trout and analyzed their gene sequences, revealing that rainbow trout TRIM23 and TRIM32 proteins are closely related to Atlantic salmon and Chinook salmon; In this experiment, the TRIM23 and TRIM32 protein genes were resoundingly constructed as a recombinant plasmids and expressed in CHSE-214 cells. Upon transfected with the recombinant plasmid, followed by viral infection, significant decreasion in the copy numbers of the virus was observed, indicating that the TRIM23 and TRIM32 proteins of rainbow trout play an important role in inhibiting virus replication, with the TRIM32 role being the most pronounced. These results provide a basis for subsequent in-depth study of the antiviral effects of TRIM proteins, and provide new ideas for immune enhancers.

Aminophosphate precursors for the synthesis of near-unity emitting InP quantum dots and their application in liver cancer diagnosis.

InP quantum dots (QDs) are a promising and environment-friendly alternative to Cd-based QDs for in vitro diagnostics and bioimaging applications. However, their poor fluorescence and stability severely limit their biological applications. Herein, we synthesize bright (∼100%) and stable InP-based core/shell QDs by using cost-effective and low-toxic phosphorus source, and then aqueous InP QDs are prepared with quantum yield over 80% by shell engineering. The immunoassay of alpha-fetoprotein can be detected in the widest analytical range of 1-1000 ng ml-1 and the limit of detection of 0.58 ng ml-1 by using those InP QDs-based fluorescent probes, making it the best-performing heavy metal-free detection reported so far, comparable to state-of-the-art Cd-QDs-based probes. Furthermore, the high-quality aqueous InP QDs exhibit excellent performance in specific labeling of liver cancer cells and in vivo tumor-targeted imaging of live mice. Overall, the present work demonstrates the great potential of novel high-quality Cd-free InP QDs in cancer diagnosis and image-guided surgery.

Evaluation of the Biological Activity of Folic Acid-Modified Paclitaxel-Loaded Gold Nanoparticles.

PURPOSE: Gold nanoparticles (AuNPs) with good physical and biological properties are often used in medicine, diagnostics, food, and similar industries. This paper explored an AuNPs drug delivery system that had good target selectivity for folate-receptor overexpressing cells to induce apoptosis. METHODS: A novel drug delivery system, Au@MPA-PEG-FA-PTX, was developed carrying paclitaxel (PTX) on folic acid (FA) and polyethylene glycol (PEG)-modified AuNPs. The nanomaterial was characterized by transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), and ultraviolet-visible spectroscopy (UV-Vis). Also, the biological activity of the AuNPs drug delivery system was examined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in HL-7702, Hela, SMMC-7721, and HCT-116 cells. Furthermore, apoptotic activity using annexin V-FITC, mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) levels was estimated by flow cytometry and fluorescence microscopy. RESULTS: Au@MPA-PEG-FA-PTX exhibited a distinct core-shell structure with a controllable size of 28±1 nm. Also, the AuNPs maintained good dispersion and spherical shape uniformity before and after modification. The MTT assay revealed good antitumor activity of the Au@MPA-PEG-FA-PTX against the Hela, SMMC-7721, and HCT-116 cells, while Au@MPA-PEG-FA-PTX produced better pharmacological effects than PTX in isolation. Further mechanistic investigation revealed that effective internalization of AuNPs by folate-receptor overexpressing cancer cells induced cell apoptosis through excessive production of intracellular ROS. CONCLUSION: The AuNPs drug delivery system showed good target selectivity for folate-receptor overexpressing cancer cells to induce target cell-specific apoptosis. These AuNPs may have great potential as theranostic agents such as in cancer.

Mesoporous silica nanoparticles loaded with fluorescent coumarin-5-fluorouracil conjugates as mitochondrial-targeting theranostic probes for tumor cells.

In this study, a nanodrug carrier (mesoporous silica nanoparticle (MSN)-SS-cysteamine hydrochloride (CS)-hyaluronic acid (HA)) for targeted drug delivery was prepared using MSNs, in which HA was used as a targeting ligand and blocking agent to control drug release. Coumarin is a fluorescent molecule that targets mitochondria. Two conjugates (XDS-DJ and 5-FUA-4C-XDS) were synthesized by chemically coupling nitrogen mustard and 5-fluorouracil with coumarin, which was further loaded into MSN-SS-CS-HA nanocarriers. MTT analysis demonstrated that the nanocomposite MSN-SS-CS@5-FUA-4C-XDS/HA displayed stronger cytotoxicity toward HCT-116 cells than HeLa or QSG-7701 cells. Furthermore, MSN-SS-CS@5-FUA-4C-XDS/HA was able to target the mitochondria of HCT-116 cells, causing decreased mitochondrial membrane potential and excessive production of reactive oxygen species. These results indicate that MSN-SS-CS@5-FUA-4C-XDS/HA has the potential to be a nanodrug delivery system for the treatment of colon cancer.

Hyaluronic Acid-Modified and Doxorubicin-Loaded Gold Nanoparticles and Evaluation of Their Bioactivity.

Functionalized gold nanoparticles (AuNPs) have been successfully used in many fields as a result of having low cytotoxicity, good biocompatibility, excellent optical properties, and their ability to target cancer cells. Here, we synthesized AuNP carriers that were modified by hyaluronic acid (HA), polyethylene glycol (PEG), and adipic dihydrazide (ADH). The antitumor drug doxorubicin (Dox) was loaded into AuNP carriers and attached chemically. The Au nanocomposite AuNPs@MPA-PEG-HA-ADH-Dox was able to disperse uniformly in aqueous solution, with a diameter of 15 nm. The results of a 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay indicated that AuNP carriers displayed very little toxicity toward cells in high doses, although the antitumor properties of Au nanocomposites were significantly enhanced. Cellular uptake experiments demonstrated that AuNPs modified with hyaluronic acid were more readily ingested by HepG2 and HCT-116 cells, as they have a large number of CD44 receptors. A series of experiments measuring apoptosis such as Rh123 and annexin V-FITC staining, and analysis of mitochondrial membrane potential (MMP) analysis, indicated that apoptosis played a role in the inhibition of cell proliferation by AuNPs@MPA-PEG-HA-ADH-Dox. Excessive production of reactive oxygen species (ROS) was the principal mechanism by which the Au nanocomposites inhibited cell proliferation, leading to apoptosis. Thus, the Au nanocomposites, which allowed cell imaging in real-time and induced apoptosis in specific cell types, represent theragnostic agents with potential for future clinical applications in bowel cancer.

Simultaneous Improvement of Efficiency and Lifetime of Quantum Dot Light-Emitting Diodes with a Bilayer Hole Injection Layer Consisting of PEDOT:PSS and Solution-Processed WO3.

Even though chemically stable metal oxides (MOs), as substitutes for poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), have been successfully adopted for improving device stability in solution-processed quantum dot light-emitting diodes (QLEDs), the efficiencies of QLEDs are at a relatively low level. In this work, a novel architecture of QLEDs has been introduced, in which inorganic/organic bilayer hole injection layers (HILs) were delicately designed by inserting an amorphous WO3 interlayer between PEDOT:PSS and the indium tin oxide anode. As a result, the efficiency and operational lifetime of QLEDs were improved simultaneously. The results show that the novel architecture QLEDs relative to conventional PEDOT:PSS-based QLEDs have an enhanced external quantum efficiency by a factor of 50%, increasing from 8.31 to 12.47%, meanwhile exhibit a relatively long operational lifetime (12 551 h) and high maximum brightness (>40 000 cd m-2) resulting from a better pathway for hole injection with staircase energy-level alignment of the HILs and reduction of surface roughness. Our results demonstrate that the novel architecture QLEDs using bilayer MO/PEDOT:PSS HILs can achieve long operational lifetime without sacrificing efficiency.

CdSe/ZnS quantum dots based fluorescence quenching method for determination of paeonol.

Aqueous polymethylmethacrylate (PMMA)-capped CdSe/ZnS quantum dots were used as fluorescence probes for paeonol determination. Based on the fluorescence quenching of aqueous CdSe/ZnS quantum dots caused by paeonol, a simple, sensitive and rapid method was developed. Under the optimal conditions, with excitation and emission wavelengths at 350 nm and 620 nm, respectively, the calibration plot of F0-F with concentration of paeonol was linear in the range of 25.04-175.2 mg L(-1) with correlation coefficient of 0.9986. The limit of detection was 0.017 mg L(-1). The concentration of paeonol in paeonol ointment was determined by the proposed method and the result agreed with the claimed value. Furthermore, the possible fluorescence quenching mechanism was discussed.

Efficient synthesis of tetradecafluoro-4-phenylheptan-4-ol by a Cannizzaro-type reaction and application of the alcohol as a bulky Martin ligand variant for a new anti-apicophilic phosphorane.

Alcohols 8 bearing two identical perfluoroalkyl groups were prepared by the reaction of the corresponding perfluoroalkyl phenyl ketones 7 with 0.5 equivalents of t-BuOK via Cannizzaro-type disproportionation. Utilizing the new bulky bidentate ligand with two n-C(3)F(7) groups generated from 8c, anti-apicophilic phosphorane 5a and its stable isomer 6a were synthesized. The crystal structures of 5a and 6a were slightly affected by the steric repulsion of heptafluoropropyl groups. Kinetic studies on the isomerization of 5a to 6a showed that the new ligand was effective for decreasing the isomerization rate compared with its C(2)F(5) analog 3a to about half.

Bright and color-saturated emission from blue light-emitting diodes based on solution-processed colloidal nanocrystal quantum dots.

We report a multilayer solution-processed blue light-emitting diode based on colloidal core/shell CdS/ZnS nanocrystal quantum dots (QDs). At a low-operating voltage of 5.5 V, the device emits spectrally pure blue radiation at 460 nm with a narrow full-width-at-half-maximum bandwidth of 20 nm and high brightness up to 1600 cd/m2. Broad-band, long-wavelength emission from the polymer components and deep traps in the QDs are minimized to less than 5% of the total emission.

Association of polymorphisms in vascular endothelial growth factor gene with the age of onset of amyotrophic lateral sclerosis.

This study investigated the association between polymorphisms in vascular endothelial growth factor (VEGF) gene (-1558C-T, -1190A-G and -1154A-G) and age at onset of amyotrophic lateral sclerosis (ALS). Between July 2000 and June 2004 we conducted a clinical genetic study at Peking University Third Hospital, China. The analyses included a total of 93 ALS patients. Genotyping was performed by using the 5'-nuclease assay technology (Applied Biosystems) with TaqMan allele-specific fluorogenic oligonucleotide probes. We used multivariate linear regression modelling and haplotype-based association test to analyse the association of VEGF gene polymorphisms with the age of onset, adjusting for initial symptoms and sex. The results indicated that patients with the -1190A/G and -1190G/G genotypes exhibited about a 4.1- and 9.4-years earlier onset of ALS than the patients with the -1190A/A genotype. A similar pattern emerged when the VEGF -1154A-G gene was considered: the beta was -7.9(p<0.001) years and -11.7(p<0.001) years for -1154A/G and -1154G/G genotypes, respectively. The VEGF -1558C-T had a positive effect in the -1558C/T group (p = 0.007, beta = 7.0) and -1558T/T (p<0.001, beta = 9.6) compared to the -1558C/C group. We neither observed an interaction nor haplotype association with age onset among -1558C-T, -1190A-G and -1154A-G. In conclusion, our results indicate, for the first time, that there was an important association between the polymorphism of the VEGF gene and age of ALS onset. This suggests a possible role for VEGF variability in the aetiology of individual differences in ALS onset.

Dedifferentiation of adult human myoblasts induced by ciliary neurotrophic factor in vitro.

Ciliary neurotrophic factor (CNTF) is primarily known for its important cellular effects within the nervous system. However, recent studies indicate that its receptor can be highly expressed in denervated skeletal muscle. Here, we investigated the direct effect of CNTF on skeletal myoblasts of adult human. Surprisingly, we found that CNTF induced the myogenic lineage-committed myoblasts at a clonal level to dedifferentiate into multipotent progenitor cells--they not only could proliferate for over 20 passages with the expression absence of myogenic specific factors Myf5 and MyoD, but they were also capable of differentiating into new phenotypes, mainly neurons, glial cells, smooth muscle cells, and adipocytes. These "progenitor cells" retained their myogenic memory and were capable of redifferentiating into myotubes. Furthermore, CNTF could activate the p44/p42 MAPK and down-regulate the expression of myogenic regulatory factors (MRFs). Finally, PD98059, a specific inhibitor of p44/p42 MAPK pathway, was able to abolish the effects of CNTF on both myoblast fate and MRF expression. Our results demonstrate the myogenic lineage-committed human myoblasts can dedifferentiate at a clonal level and CNTF is a novel regulator of skeletal myoblast dedifferentiation via p44/p42 MAPK pathway.

Increased heme oxygenase-1 expression in infarcted rat hearts following human bone marrow mesenchymal cell transplantation.

Heme oxygenase-1 (HO-1) plays an important role in oxidative stress and recent studies indicate that it is a graft survival protein in cardiac and liver transplant models. In this study, we investigated the relation between the expressions of HO-1 and the effects of human bone marrow mesenchymal cells (MSCs) transplantation to xenogenic rat hearts with experimental myocardial infarction (MI). A total of 5 x 10(6) cells in 100 microl PBS or equal volume PBS alone were injected into the ischemic zones immediately post-MI. At 1, 3, and 7 days post-MI, cardiac function was evaluated by echocardiography, the expression of HO-1 was assessed by real-time PCR and Western blot, the localization of HO-1 protein was determined under immunofluorescence microscopy. The infarct size was examined by histology. The numbers of Hoechst-33342 positive MSCs were evaluated under immunofluorescence microscopy and also by flow cytometry after isolation from the host hearts. The results indicated that the HO-1 expressions were markedly increased at both mRNA and protein levels in comparison with injection of PBS at each time point post MSCs transplantation (P < 0.01). HO-1 was revealed both in transplanted MSCs and recipient cardiomyocytes by immunofluorescence. Up-regulated HO-1 expression was accompanied by increase of the numbers of Hoechst-33342 positive MSCs, the reduction of infarct size, and the improvement of cardiac function. Transplantation of human MSCs could up-regulate HO-1 expression in infarct rat hearts, which might play an important role in protecting transplanted MSCs, cardiomyocytes survival, and cardiac function improvement during the early stage after MI.

Purified human bone marrow multipotent mesenchymal stem cells regenerate infarcted myocardium in experimental rats.

Recent findings suggest the feasibility of cardiac repair by transplantation of bone marrow mesenchymal stem cell (MSCs). However, it remains controversial regarding which cell type is the best source for transplanting into the ischemic heart because of lack of well-defined cell markers. In this study, we investigated the in vitro and in vivo effects of the novel multipotent marrow mesenchymal stem cells (MMSCs) from human bone marrow. Pluripotent markers (Oct4, Bmi1, and Abcg2) and vascular endothelial growth factor (VEGF) were detected by RT-PCR and immunofluorescence in MMSCs. Myocardial differentiation was induced in the expanded MMSC cultures by treatment with 5-azacyline. Expressions of VEGF in the animals transplanted with MMSCs were markedly increased in comparison with the animals injected with fibroblasts or saline at both mRNA and protein levels. VEGF expression was observed in both transplanted MMSCs and recipient cardiomyocytes by immunofluorescence. Confocal immunofluorescence microscopy revealed the specific markers for cardiomyocytes and endothelial cells in transplanted MMSCs 14 days after transplantation. Vessel count was increased and left ventricular function improved post-MMSC transplantation. These results indicate that transplantation of purified MMSCs from human bone marrow upregulated VEGF expression, enhanced angiogenesis, and improved the functional recovery following myocardial infarction in rats.

Fetal human neural progenitors can be the target for tumor transformation.

The hypothesis that stem cells may seed cancer has emerged from the cancer stem cells concept. However, the experimental systems necessary to provide more direct evidence to support the hypothesis have been lacking. We have used fetal neural progenitor cells (hNPC) transduced with the telomerase hTERT gene to investigate the neoplastic potential of hNPCs. The hTERT-transduced line, hNPCs-G3 lost normal diploid karyotype, showed loss of contact inhibition, anchorage independence, and formed neuroblastoma-like tumours in all of 10 mice. These data suggest that hNPCs have the potential for neoplastic transformation. These data have implications for providing a novel tool to test the feasibility of new anticancer treatment strategies and raise the possibility of a risk for the use of hNPCs in cell transplantation.

Elevation of NMDAR after transplantation of neural stem cells.

Cognitive deficits could be alleviated by transplantation of neural stem cells in animals. Grafted cells may differentiate into neurons, thereby improving animal cognition. Alternatively, grafted cells may provide neurotrophic factors to modify neuronal functions and to alleviate cognitive deficits. To test which mechanism is underlying this recovery process, senescence-accelerated mice were transplanted with human neural stem cells into the hippocampus. The effect of cell transplantation was assessed in the Morris water maze. The survival and differentiation of grafted cells and the expression of NMDA receptors were examined. The data suggested that in addition to the neural differentiation of grafted neural stem cells, up-regulation of NMDA receptors after transplantation also contributed to the alleviation of cognitive deficits in this animal model.

Distinct efficacy of pre-differentiated versus intact fetal mesencephalon-derived human neural progenitor cells in alleviating rat model of Parkinson's disease.

Neural progenitor cells have shown the effectiveness in the treatment of Parkinson's disease, but the therapeutic efficacy remains variable. One of important factors that determine the efficacy is the necessity of pre-differentiation of progenitor cells into dopaminergic neurons before transplantation. This study therefore investigated the therapeutic efficacy of mesencephalon-derived human neural progenitor cells with or without the pre-differentiation in alleviating a rat model of Parkinson's disease. We found that a combination of 50 ng/ml fibroblast growth factor 8, 10 ng/ml glial cell line-derived neurotrophic factor and 10 microM forskolin facilitated the differentiation of human fetal mesencephalic progenitor cells into dopaminergic neurons in vitro. More importantly, after transplanted into the striatum of parkinsonian rats, only pre-differentiated grafts resulted in an elevated production of dopamine in the transplanted site and the amelioration of behavioral impairments of the parkinsonian rats. Unlike pre-differentiated progenitors, grafted intact progenitors rarely differentiated into dopaminergic neurons in vivo and emigrated actively away from the transplanted site. These data demonstrates the importance of pre-differentiation of human progenitor cells before transplantation in enhancing therapeutic potency for Parkinson's disease.

Forskolin cooperating with growth factor on generation of dopaminergic neurons from human fetal mesencephalic neural progenitor cells.

Forskolin was tested for its co-activating ability to enhance the function of fibroblast growth factor (FGF) 8 on dopaminergic (DAergic) differentiation from human fetal mesencephalic neural progenitor cells (NPCs). When NPCs were treated with FGF8 alone, the DAergic phenotype was expressed lightly. The addition of 10 microM forskolin increased the number of DAergic neurons, cooperating with 50 ng/ml FGF8. These cells produced neurotransmitter DA, which was measured by high-performance liquid chromatography. Reverse transcriptase-polymerase chain reaction analysis demonstrated that differentiated cells expressed DAergic development-relative genes tyrosine hydroxylase (TH), nuclear receptor-related factor 1 (Nurr1) and D2 receptor (D2R), indicating that matured DAergic neurons could be obtained under these present conditions. The results suggest that forskolin plus FGF8 may contribute to more efficient production of DAergic neurons from human-derived NPCs for therapy of neurodegenerative diseases.

Attenuation of SARS coronavirus by a short hairpin RNA expression plasmid targeting RNA-dependent RNA polymerase.

Severe acute respiratory syndrome (SARS) is a highly contagious and sometimes a lethal disease, which spread over five continents in 2002-2003. Laboratory analysis showed that the etiologic agent for SARS is a new type of coronavirus. Currently, there is no specific treatment for this disease. RNA interference (RNAi) is a recently discovered antiviral mechanism in plant and animal cells that induces a specific degradation of double-stranded RNA. Here, we provide evidences that RNAi targeting at coronavirus RNA-dependent RNA polymerase (RDRP) using short hairpin RNA (shRNA) expression plasmids can specifically inhibit expression of extraneous coronavirus RDRP in 293 and HeLa cells. Moreover, this construct significantly reduced the plaque formation of SARS coronaviruses in Vero-E6 cells. The data may suggest a new approach for treatment of SARS patients.