Activatable Near-Infrared Fluorescent and Photoacoustic Dual-Modal Probe for Highly Sensitive Imaging of Sulfatase In Vivo.

Sulfatase is an important biomarker closely associated with various diseases. However, the state-of-the-art sulfatase probes are plagued with a short absorption/emission wavelength and limited sensitivity. Developing highly sensitive fluorescent probes for in vivo imaging of sulfatase remains a grand challenge. Herein, for the first time, an activatable near-infrared fluorescence/photoacoustic (NIRF/PA) dual-modal probe (Hcy-SA) for visualizing sulfatase activity in living cells and animals is developed. Hcy-SA is composed of a sulfate ester moiety as the recognition unit and a NIR fluorophore hemicyanine (Hcy-OH) as the NIRF/PA reporter. The designed probe exhibits a rapid response, excellent sensitivity, and high specificity for sulfatase detection in vitro. More importantly, cells and in vivo experiments confirm that Hcy-SA can be successfully applied for PA/NIRF dual-modal imaging of sulfatase activity in living sulfatase-overexpressed tumor cells and tumor-bearing animals. This probe can serve as a promising tool for sulfatase-related pathological research and cancer diagnosis.

Impact of catheter-tissue contact force on lesion size during right ventricular outflow tract ablation in a swine model.

BACKGROUND: The catheter-tissue contact force (CF) is one of the significant determinants of lesion size and thus has a considerable impact on the effectiveness of ablation procedures. This study aimed to evaluate the impact of CF on the lesion size during right ventricular outflow tract (RVOT) ablation in a swine model. METHODS: Twelve Guangxi Bama miniature male pigs weighing 40 to 50 kg were studied. After general anesthesia, a ThermoCool SmartTouch contact-sensing ablation catheter was introduced to the RVOT via the femoral vein under the guidance of the CARTO 3 system. The local ventricular voltage amplitude and impedance were measured using different CF levels. We randomly divided the animals into the following four groups according to the different CF levels: group A (3-9 g); group B (10-19 g); group C (20-29 g); and group D (30-39 g). Radiofrequency ablations were performed at three points in the free wall and septum of the RVOT in power control mode at 30 W for 30 s while maintaining the saline irrigation rate at 17 mL/min. At the end of the procedures, the maximum depth, surface diameter, and lesion volume were measured and recorded. A linear regression analysis was performed to determine the relationship between continuous variables. RESULTS: A total of 72 ablation lesions were created in the RVOT of the 12 Bama pigs. The maximum depth, surface diameter, and volume of the lesions measured were well correlated with the CF (free wall: ß = 0.105, ß = 0.162, ß = 3.355, respectively, P < 0.001; septum: ß = 0.093, ß = 0.150, ß = 3.712, respectively, P < 0.001). The regional ventricular bipolar voltage amplitude, unipolar voltage amplitude, and impedance were weakly positively associated with the CF (ß = 0.065, ß = 0.125, and ß = 1.054, respectively, P < 0.001). There was a significant difference in the incidence of steam pops among groups A, B, C, and D (free wall: F = 7.3, P = 0.032; septum: F = 10.5, P = 0.009); and steam pops occurred only when the CF exceeded 20 g. Trans-mural lesions were observed when the CF exceeded 10 g in the free wall, while the lesions in the septum were non-trans-mural even though the CF reached 30 g. CONCLUSIONS: CF seems to be a leading predictive factor for the size of formed lesions in RVOT ablation. Maintaining the CF value between 3 and 10 g may be reasonable and effective for creating the necessary lesion size and reducing the risk of complications, such as steam pops and perforations.

Orbital myiasis: A case report and literature review.

RATIONALE: Myiasis is a parasitic disease caused by fly larvae of the Diptera order that infest human and other vertebrate animal tissues. Orbital myiasis is a potentially destructive infestation of the orbital tissues, which may affect individuals with previous ocular diseases or disorders of consciousness. PATIENT CONCERNS: A 72-year-old man presented with a complaint of repeated pain for two years after trauma to his right eyelid and aggravated symptoms with larvae wriggling out for 2 days. An orbital computed tomography scan revealed right eyeball protrusion and periocular soft tissue edema. Two days later, magnetic resonance imaging showed that the shape of the right eyeball was changed and that the normal structure of the eyeball could not be identified. DIAGNOSES: Due to the patient's symptoms and imaging examination results, the diagnosis of orbital myiasis was made. INTERVENTIONS: The patient was treated by exenteration of the right orbit, and all necrotic tissues and larvae were removed. The defect was repaired via reconstruction with a pedicled musculocutaneous flap from the forehead region. Antibiotics and tetanus toxoid therapy were utilized to prevent potential bacterial infection. OUTCOMES: The patient recovered well postoperatively and was discharged uneventfully. During the 6-month follow-up period, the wound healed well. LESSONS: Advanced age and untreated eye trauma are risk factors for orbital myiasis. Timely removal of larvae and elimination of infections are important measures for protecting the eyeball.

MicroRNA-93-5p increases multidrug resistance in human colorectal carcinoma cells by downregulating cyclin dependent kinase inhibitor 1A gene expression.

Multidrug resistance (MDR) impedes successful chemotherapy in colorectal carcinoma (CRC) and emerging evidence suggests that microRNAs (miRs) are involved in the development of MDR. In the present study, the role of miR-93-5p in the modulation of drug resistance in CRC was investigated using HCT-8 and MDR HCT-8/vincristine (VCR) cell lines. The results demonstrated upregulated expression of miR-93-5p and MDR protein 1 (MDR1) in HCT-8/VCR cells, compared with the parental HCT-8 cells. Furthermore, cyclin-dependent kinase inhibitor 1A (CDKN1A) was identified as a potential target of miR-93-5p using miR target analysis tools, including PicTar, TargetScan and miRanda. In addition, inhibition of miR-93-5p expression in HCT-8/VCR cells markedly downregulated MDR1 gene expression, upregulated CDKN1A gene expression and induced cell cycle arrest in G1. Conversely, the overexpression of miR-93-5p in HCT-8/VCR cells upregulated MDR1 gene expression, downregulated CDKN1A gene expression and promoted G1/S transition. Furthermore, the in vitro drug sensitivity assay performed suggested that downregulation of miR-93-5p enhanced the sensitivity of HCT-8/VCR cells to VCR, while the upregulation of miR-93-5p decreased the sensitivity of HCT-8 cells to VCR. In conclusion, the results of the present study suggest that miR-93-5p serves a role in the development of MDR through downregulating CDKN1A gene expression in CRC.

Plasma oxidative stress and inflammatory biomarkers are associated with the sizes of the left atrium and pulmonary vein in atrial fibrillation patients.

BACKGROUND: Oxidative stress and inflammatory processes are responsible for the pathogenesis of AF, but their relationship with the sizes of the LA and PVs in AF patients remains unclear. HYPOTHESIS: Oxidative stress and inflammatory processes are associated with the sizes of the LA and PVs in AF patients. METHODS: 82 AF patients were compared to 30 control patients by using a case-control study design. Oxidative stress, inflammatory biomarkers and the sizes of the LA and PVs were detected. RESULTS: (1) Hs-CRP, IL-6, IL-8, TNF-α, MDA and ox-LDL were higher, and SOD was lower in AF patients than in control patients. Hs-CRP, MDA and ox-LDL were higher in permanent AF patients than in paroxysmal and persistent AF patients. (2) CsA of LSPV, RSPV, RIPV, LAA and LAV were statistically higher in AF patients than in control patients. CsA of RSPV, LSPV, LIPV and LAV were higher in permanent AF patients than in paroxysmal and persistent AF patients. (3) In the AF group, hs-CRP and TNF-α were positively correlated with LAV; MDA was positively correlated with CsA of LAA, LSPV and LAV; SOD was passively correlated with CsA of LAA and LAV; ox-LDL was positively correlated with CsA of LAA and LAV. Multivariate logistic regression analysis showed hs-CRP, ox-LDL, RSPV CsA, LIPV CsA and LAV were associated with AF. CONCLUSIONS: Oxidative stress, inflammatory biomarkers and the sizes of the LA and PVs were significantly increased in AF patients. Hs-CRP, ox-LDL, RSPV CsA, LIPV CsA and LAV were associated with AF persistence.

Role of LAP+CD4+ T cells in the tumor microenvironment of colorectal cancer.

AIM: To investigate the abundance and potential functions of LAP+CD4+ T cells in colorectal cancer (CRC). METHODS: Proportions of LAP+CD4+ T cells were examined in peripheral blood and tumor/paratumor tissues of CRC patients and healthy controls using flow cytometry. Expression of phenotypic markers such as forkhead box (Fox)p3, cytotoxic T-lymphocyte-associated protein (CTLA)-4, chemokine CC receptor (CCR)4 and CCR5 was measured using flow cytometry. LAP-CD4+ and LAP+CD4+ T cells were isolated using a magnetic cell-sorting system and cell purity was analyzed by flow cytometry. Real-time quantitative polymerase chain reaction was used to measure expression of cytokines interleukin (IL)-10 and transforming growth factor (TGF)-ß. RESULTS: The proportion of LAP+CD4+ T cells was significantly higher in peripheral blood from patients (9.44% ± 3.18%) than healthy controls (1.49% ± 1.00%, P < 0.001). Among patients, the proportion of LAP+CD4+ T cells was significantly higher in tumor tissues (11.76% ± 3.74%) compared with paratumor tissues (3.87% ± 1.64%, P < 0.001). We also observed positive correlations between the proportion of LAP+CD4+ T cells and TNM stage (P < 0.001), distant metastasis (P < 0.001) and serum level of carcinoembryonic antigen (P < 0.05). Magnetic-activated cell sorting gave an overall enrichment of LAP+CD4+ T cells (95.02% ± 2.87%), which was similar for LAP-CD4+ T cells (94.75% ± 2.76%). In contrast to LAP-CD4+ T cells, LAP+CD4+ T cells showed lower Foxp3 expression but significantly higher levels of CTLA-4, CCR4 and CCR5 (P < 0.01). LAP+CD4+ T cells expressed significantly larger amounts of IL-10 and TGF-ß but lower levels of IL-2, IL-4, IL-17 and interferon-γ, compared with LAP-CD4+ T cells. CONCLUSION: LAP+CD4+ T cells accumulated in the tumor microenvironment of CRC patients and were involved in immune evasion mediated by IL-10 and TGF-ß.

Exceptionally High Negative Electro-Caloric Effects of Poly(VDF⁻co⁻TrFE) Based Nanocomposites Tuned by the Geometries of Barium Titanate Nanofillers.

Exceptionally high electro-caloric effects (ECEs) are observed in nanocomposites consisting of poly(vinylidene fluoride-co-trifluoroethylene) (VDF⁻co⁻TrFE) copolymer and barium titanate (BT) nanoparticles and nanowires. The poly(VDF⁻co⁻TrFE) matrix nanocomposites containing 5% volume fraction of BT nanowires are found to exhibit a negative ECE temperature change as large as 12 °C or a refrigeration effect of 8.3 J/g, which is much larger than those reported to date. The mechanisms of negative ECE and the enhanced negative ECE in the nanocomposites consisting of poly(VDF⁻co⁻TrFE) and BT nanowires are explained by the Kauzmann theory on glassy polar states and the interaction between BT nanofillers and the copolymer matrix. The effects of geometries of BT nanofillers on the negative ECEs are elucidated by P-E loop measurements, and dielectric and dynamical mechanical analyses. The nanocomposites, with their enhanced negative ECE tuned by the geometries of BT nanofillers, provide us with promising ECE refrigerants for practical application to small-sized and environmentally-friendly ECE coolers in the heat management of electronic devices.

Th22 cell accumulation is associated with colorectal cancer development.

AIM: To investigate the expression of Th22 cells and related cytokines in colorectal cancer (CRC) tissues, and the probably mechanism. METHODS: CRC tumor and paratumor tissues were collected to detect the expression levels of Th22 cells and of related cytokines by immunohistochemistry, flow cytometry and real-time quantitative polymerase chain reaction (RT-qPCR). Interleukin (IL)-22 alone or with a STAT3 inhibitor was co-cultured with RKO cells in vitro to study the effects of IL-22 on colon cancer cells. IL-22 alone or with a STAT3 inhibitor was injected into a BALB/c nude mouse model with subcutaneously transplanted RKO cells to study the effects of IL-22 on colon cancer growth. RESULTS: The percentage of Th22 cells in the CD4(+) T subset was significantly higher in tumor tissues compared with that in paratumor tissues (1.47% ± 0.083% vs 1.23% ± 0.077%, P < 0.05) as determined by flow cytometry. RT-qPCR analysis revealed that the mRNA expression levels of IL-22, aryl hydrocarbon receptor, CCL20 and CCL22 were significantly higher in tumor tissues compared with those in paratumor tissues. CCL27 mRNA also displayed a higher expression level in tumor tissues compared with that in paratumor tissues; however, these levels were not significantly different (2.58 ± 0.93 vs 2.30 ± 0.78, P > 0.05). IL-22 enhanced colon cancer cell proliferation in vitro and displayed anti-apoptotic effects; these effects were blocked by adding a STAT3 inhibitor. IL-22 promoted tumor growth in BALB/c nude mice; however, this effect was reversed by adding a STAT3 inhibitor. CONCLUSION: Th22 cells that accumulate in CRC may be associated with the chemotactic effect of the tumor microenvironment. IL-22 is associated with CRC development, most likely via STAT3 activation.

Qualitative and quantitative analysis of Andrographis paniculata by rapid resolution liquid chromatography/time-of-flight mass spectrometry.

A rapid resolution liquid chromatography/time-of-flight tandem mass spectrometry (RRLC-TOF/MS) method was developed for qualitative and quantitative analysis of the major chemical constituents in Andrographis paniculata. Fifteen compounds, including flavonoids and diterpenoid lactones, were unambiguously or tentatively identified in 10 min by comparing their retention times and accurate masses with standards or literature data. The characteristic fragmentation patterns of flavonoids and diterpenoid lactones were summarized, and the structures of the unknown compounds were predicted. Andrographolide, dehydroandrographolide and neoandrographolide were further quantified as marker substances. It was found that the calibration curves for all analytes showed good linearity (R² > 0.9995) within the test ranges. The overall limits of detection (LODs) and limits of quantification (LOQs) were 0.02 µg/mL to 0.06 µg/mL and 0.06 µg/mL to 0.2 µg/mL, respectively. The relative standard deviations (RSDs) for intra- and inter-day precisions were below 3.3% and 4.2%, respectively. The mean recovery rates ranged from 96.7% to 104.5% with the relative standard deviations (RSDs) less than 2.72%. It is concluded that RRLC-TOF/MS is powerful and practical in qualitative and quantitative analysis of complex plant samples due to time savings, sensitivity, precision, accuracy and lowering solvent consumption.

Supersaturation-dependent surface structure evolution: from ionic, molecular to metallic micro/nanocrystals.

Deduced from thermodynamics and the Thomson-Gibbs equation that the surface energy of crystal face is in proportion to the supersaturation of crystal growth units during the crystal growth, we propose that the exposed crystal faces can be simply tuned by controlling the supersaturation, and higher supersaturation will result in the formation of crystallites with higher surface-energy faces. We have successfully applied it for the growth of ionic (NaCl), molecular (TBPe), and metallic (Au, Pd) micro/nanocrystals with high-surface-energy faces. The above proposed strategy can be rationally designed to synthesize micro/nanocrystals with specific crystal faces and functionality toward specific applications.

General and facile syntheses of metal silicate porous hollow nanostructures.

Porous hollow nanostructures have attracted intensive interest owing to their unique structure and promising applications in various fields. A facile hydrothermal synthesis has been developed to prepare porous hollow nanostructures of silicate materials through a sacrificial-templating process. The key factors, such as the concentration of the free metal cation and the alkalinity of the solution, are discussed. Porous hollow nanostructures of magnesium silicate, nickel silicate, and iron silicate have been successfully prepared by using SiO(2) spheres as the template, as well as a silicon source. Several yolk-shell structures have also been fabricated by a similar process that uses silica-coated composite particles as a template. As-prepared mesoporous magnesium silicate hollow spheres showed an excellent ability to remove Pb(2+) ions in water treatment owing to their large specific surface and unique structures.

Epitaxial growth of heterogeneous metal nanocrystals: from gold nano-octahedra to palladium and silver nanocubes.

With octahedral Au nanocrystals as seeds, highly monodisperse Au@Pd and Au@Ag core-shell nanocubes were synthesized by a two-step seed-mediated method in aqueous solution. Accordingly, we have preliminarily proposed a general rule that the atomic radius, bond dissociation energy, and electronegativity of the core and shell metals play key roles in determining the conformal epitaxial layered growth mode.

Preparation and optical properties of ThO(2) and Eu-doped ThO(2) nanotubes by the sol-gel method combined with porous anodic aluminum oxide template.

In this paper, we report the synthesis of thorium oxide and Eu-doped thorium oxide nanotubes for the first time using the sol-gel method in porous anodic aluminum oxide template. Transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were applied to characterize the morphology and structure of the as-prepared nanotubes. It has been demonstrated that Eu(3+) ions were homogeneously doped into the ThO(2) crystal lattice. The optical properties resulting from Eu-doped products were investigated by means of photoluminescence spectroscopy. Strong visible light emissions were observed at low doping concentration, and the luminescent intensity decreased at high doping concentration. The luminescent centers were concluded to be the Eu(3+) ions in the cubic (O(h)) sites rather than the C(3v) sites, which accounted well for the decrease of luminescent intensity at high doping concentration.

Formation of ZnO hexagonal micro-pyramids: a successful control of the exposed polar surfaces with the assistance of an ionic liquid.

Wurtzite ZnO hexagonal micro-pyramids, with all exposed surfaces being polar +/- (0001) and {1011} planes, have been successfully synthesized using ionic liquids as solvents.

Molten salt route toward the growth of ZnO nanowires in unusual growth directions.

ZnO nanowires with unusual growth directions, such as the approximate 102 and the 100 directions, were prepared by using the LiCl molten salt synthetic method. Intrinsic crystallographic structures and the growth directions of the as-prepared ZnO nanowires were investigated by using selected area electron diffraction and high-resolution transmission electron microscopy. In the present case, Li+ and Cl- ions of molten salts may bind with O2- and Zn2+ ions, respectively, of the {101} and {001} polar surfaces of the ZnO crystals, resulting in the decrease of their surface energies and tuning the growth directions by blocking the growth on the polar surfaces. A combination of the growth along the <102>, <100>, and <210> directions may lead to the formation of complex tree like ZnO dendrites. Strong green light emission was observed from room-temperature PL spectra of the as-prepared ZnO nanowires. This molten-salt synthetic process could be extended to synthesize other kinds of unusual 1D nanomaterials with specific crystal structures and properties.

Shape controlled growth of gold nanoparticles by a solution synthesis.

The shape of gold nanoparticles has been successfully tuned among penta-twinned decahedrons, truncated tetrahedrons, cubes, octahedrons, hexagonal thin plates by introducing a small amount of salt into a N,N-dimethylformamide (DMF) solution containing poly(vinyl pyrrolidone) (PVP), and changing the temperature or the concentration of the gold precursor.

Tailoring the optical property by a three-dimensional epitaxial heterostructure: a case of ZnO/SnO2.

Epitaxial growth, as a best strategy to attain a heterostructure with a well-defined and clean interface, usually takes place on a planar substrate. In this paper, using a ZnO/SnO2 core-shell heterostructure as an example, we demonstrate the possibility of establishing a three-dimensional epitaxial interface between two materials with different crystal systems for the first time and show possible tailoring optical properties by building the heteroepitaxial crystal interface. The characterization results of element mapping, high-resolution transmission electron microscopy, and selected area electric diffraction reveal that the as-prepared ZnO/SnO2 heterostructure has a tetrapod-like ZnO core and a SnO2 shell with 15-30 nm, and their special epitaxial relation is (010)SnO2//(010)ZnO and [100]SnO2//[0001]ZnO. Such three-dimensional epitaxy between the ZnO core and SnO2 shell is quite different from the usual planar epitaxy or three-dimensional epitaxy between materials having the same crystal structure. A rational model of such complicated epitaxy has been proposed through investigating the certain structural comparability between the wurtzite ZnO and rutile SnO2 crystals. The as-prepared T-ZnO/SnO2 epitaxial heterostructure exhibits unique luminescence properties in contrast with individual tetrapod ZnO and SnO2 nanostructures, in which the epitaxial interface induces new luminescence properties. This result may inspire great interest in exploring other complicated epitaxy systems and their potential applications in laser, gas sensor, solar energy conversion, photo catalysis, and nanodevices in the future.

Growth of silver nanowires from solutions: a cyclic penta-twinned-crystal growth mechanism.

Silver nanowires are synthesized by simple reduction of the silver ions with reductants such as glucose, sodium citrate, and sodium hypophosphite, etc., in the absence of the so-called surfactants or capping reagents at the temperature from 80 to 200 degrees C. Regardless of the reductants, the nanowires prepared at a given temperature are uniform in diameters, ranging from 30 to 50 nm at 100 degrees C. Nanoparticles coexist with nanowires in the products with larger diameters (usually larger than 50 nm). We find that all the silver nanowires in the as-prepared products are of cyclic penta-twinned structure, where five crystallites bond by the {111} facets. We propose that the intrinsic factor of the cyclic penta-twinned structure, i.e., the angular mismatch of the five crystallites in forming a gapless rod, controls the size of the nanowires and guides the directional growth of the nanowires with {110} as the active facets. The nanoparticles in the products are aggregates of imperfect penta-twinned crystals, which inhibits them from growing into nanowires and results in larger size. From the structural information of the nanoparticles synthesized at room temperature, we propose that the formation of the cyclic penta-twinned structure is due to the stacking fault and the intrinsic equilibrium structures of the lower energy.

Synthesis of silver nanotubes by electroless deposition in porous anodic aluminium oxide templates.

An electroless deposition method has been employed for the synthesis of silver nanotubes using porous anodic aluminium oxide as templates, by which high-yield silver nanotubes with length over ten microns have been synthesized.

Starlike nanostructures of polyoxometalates K3[PMo12O40].nH2O synthesized and assembled by an inverse microemulsion method.

In a nonionic inverse microemulsion system, surfactant (C12-18EO9)/cyclohexane/water, heteropolyanions [PMo12O40]3- react with K+ to form K3[PMo12O40].nH2O nanorods and assemble as three-dimensional starlike nanostructures.