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We report here a tumor‐pretargted theranostic approach for multimodality imaging‐guided synergistic cancer PDT by cascade alkaline phosphatase (ALP)‐mediated in situ self‐assembly and bioorthogonal inverse electron demand Diels–Alder (IEDDA) reaction. Using the enzymatic catalysis of ALP that continuously catalyses the dephosphorylation and self‐assembly of trans‐cyclooctene (TCO)‐bearing P‐FFGd‐TCO, a high density of fluorescent and magnetic TCO‐containing nanoparticles (FMNPs‐TCO) can be synthesized and retained on the membrane of tumor cells. They can act as 'artificial antigens' amenable to concurrently capture lately administrated tetrazine (Tz)‐decorated PS (775NP‐Tz) and carbonic anhydrase (CA) inhibitor (SA‐Tz) via the fast IEDDA reaction. This two‐step pretargeting process can further induce FMNPs‐TCO regrowth into microparticles (FMNPs‐775/SA) directly on tumor cell membranes, which is analyzed by bio‐SEM and fluorescence imaging. Thus, efficient enrichment of both SA‐Tz and 775NP‐Tz in tumors can be achieved, allowing to alleviate hypoxia by continuously inhibiting CA activity and improving PDT of tumors. Findings show that subcutaneous HeLa tumors could be completely eradicated and no tumor recurred after irradiation with an 808 nm laser (0.33 W cm−2, 10 min). This pretargeted approach may be applied to enrich other therapeutic agents in tumors to improve targeted therapy. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Stimuli‐controlled disassembly process has shown promise to direct delivery of probes and/or spatial‐temporally control imaging signals for molecular imaging in vivo. Via the disassembly process, well defined nanoprobes with a stimulus‐responsive moiety can be controllably converted into small‐molecular imaging agents in response to a stimulus, leading to a switch in imaging signals. Moreover, the on‐site released small‐molecule probes could enhance penetration into the deep tissue for improved imaging of deep‐seated molecular targets. Therefore, such a stimuli‐controllable disassembly approach has been widely utilized to build activatable molecular imaging probes for the noninvasive detection of various molecular targets in living subjects. In this review article, we first briefly introduce the general principle of stimuli‐controlled disassembly. We then summarize the activatable probes based on different internal or external stimulus that has been utilized to control disassembly process. Activatable probes by using multiple stimuli to control cascaded in situ self‐assembly and disassembly processes are also discussed. Finally, we close with a conclusion of current challenges and perspective in this field. We wish this review paper will give readers useful information on molecular imaging via the intelligent stimuli‐controlled disassembly process. [ABSTRACT FROM AUTHOR]

The single‐phase oxides with elemental complexity and compositional diversity, usually named high entropy oxides, feature homogeneously dispersed multi‐metallic elements in equiatomic concentration. The unusual properties of high entropy oxides endow their potential application in clean‐energy‐related electrocatalysis. However, the possible fundamental relationship between configuration entropy and the underlying catalytic mechanism is still not well understood and established. Herein, a high entropy perovskite cobaltate consisting of five equimolar metals in the B‐site (Mg, Mn, Fe, Co, and Ni) is employed as an electrocatalyst for oxygen evolution reaction (OER). The configuration entropy serves as an effective tool to promote the intrinsic activity of the Co reactive site and manipulate the OER mechanism. The high entropy cobaltate demonstrates a lower overpotential of 320 mV at a current density of 10 mA cm−2, outperforming other counterparts. The X‐ray spectroscopies disclose the synergistic charge‐exchange effect among different cations and the formation of a new oxygen hole state. Combinatorially computational and experimental results unveil the enigma that the high configuration entropy leads to the random occupation of cations, facilitates the surface reconstruction, and benefits the formation of stable surface oxygen vacancies. Owing to these merits, the O2 formation is found to be kinetically favorable via the lattice oxygen mechanism. [ABSTRACT FROM AUTHOR]

The extensive emission of CO2 results in critical environmental issues, such as global warming. Photocatalytic CO2 conversion is a meaningful route to convert CO2 into useful chemicals. However, the highly selective reduction of CO2 with the avoidance of hydrogen evolution is still challenging. Herein, the photocatalytic reduction CO2 to synthesis gas (syngas) was achieved on a metal Ag socketed perovskite LaFeO3 (LFO) catalytic interface prepared by an in‐situ exsolution method. The conduction band of Ag‐exsolved LFO is more negative than LFO, benefiting efficient CO2 reduction. By tuning the dopant Ag cation in the lattice to nanoparticles pinned on the surface, the CO formation rate was improved around five‐fold from 0.51 to 2.41 μmol g−1 h−1. Meanwhile, the H2/CO molar ratio also showed strong dependence on the modality of Ag at the metal‐perovskite interface. The design offers a promising pathway for transforming CO2 to valuable chemicals based on efficient photocatalysts design. [ABSTRACT FROM AUTHOR]

A Pd/Al2O3 nanocatalyst was pretreated at 750 °C in air, Ar or H2O/Ar, respectively. The effect of these different pretreatments on the active species and reactivity of Pd/Al2O3 in formaldehyde oxidation at room temperature was investigated. The pretreatment was found to affect both the phase transformation of PdO to Pd metal and the Pd dispersion, leading to different catalytic performances. We found that the Pd/Al2O3 nanocatalyst pretreated in both Ar and H2O/Ar show 60 % and 100 % formaldehyde conversion at 25 °C, respectively, while the catalyst pretreated in air is not active under the same condition. Pretreatments in both Ar and H2O/Ar were found to facilitate the formation of metallic Pd on Pd/Al2O3 catalyst, confirmed by both experiments and calculation based on the function of the equilibrium oxygen pressure and temperature. We further found that the catalyst pretreated in H2O/Ar has higher Pd dispersion and more surface OH groups compared to that pretreated in Ar, leading to improved activity in formaldehyde oxidation. [ABSTRACT FROM AUTHOR]

Chemiluminescence (CL) is a very promising method for applications in analytic chemistry and biological systems due to the elimination of the external light source, which could reduce autofluorescence interference and improve the signal‐to‐noise ratio (SNR) and tissue penetration depth. The fluorescent dyes, chemiluminescent initiator, and reaction temperature are three crucial factors that determine the chemiluminescence efficiency. Up to now, significant development of chemiluminescence probes has been reported for high‐performance imaging and sensing, including the systems based on luminol, imidazopyrazinone, peroxyoxalate, and Schaap's dioxetane. In this review, we give an overview of the current chemiluminescence probes and their bioimaging and biosensing applications. We also provide perspectives on designing chemiluminescent probes with good efficiency and longer emission wavelengths. [ABSTRACT FROM AUTHOR]

Graphene has great potential in wearable sensors. However, the sensing selectivity of graphene‐based sensors is still a big challenge, limiting their application in the multifunctional sensors. Herein, different types and distributions of defects are introduced into graphene by femtosecond laser patterning to realize sensing selectivity for wearable multifunctional sensors. The imperfect graphene with four pattern arrays, circle, square, triangle, and hexagon with none, right, acute, and obtuse angle, is fabricated by laser to control the types and distributions of defects. The graphene with different patterns shows remarkable sensing selectivity, owing to the dangling bonds and vacancies on the edge of patterns. The graphene‐based sensor with the circle pattern array is used to detect the strain variation; the triangle one is for temperature detection; and the hexagon one can collect the information of gas. The gauge factor is demonstrated to be as high as ≈104. The as‐produced sensor with the above‐mentioned four patterns can simultaneously detect body pulse, temperature, and harmful gas by attaching to human body or clothes, offering real‐time health monitoring and protection. The patterned graphene‐based sensors with high sensing selectivity are expected to develop multifunctional sensor platform and versatile artificial electronic skin. [ABSTRACT FROM AUTHOR]

Chemiluminescence (CL) sensing without external excitation by light and autofluorescence interference has been applied to high‐contrast in vitro immunoassays and in vivo inflammation and tumor microenvironment detection. However, conventional CL sensing usually operates in the range of 400–850 nm, which limits the performance of in vivo imaging due to serious light scattering effects and signal attenuation in tissue. To address this challenge, a new type of CL sensor is presented that functions in the second near‐infrared window (NIR‐II CLS) with a deep penetration depth (≈8 mm). Successive CL resonance energy transfer (CRET) and Förster resonance energy transfer (FRET) from the activated CL substrate to two rationally designed donor‐acceptor‐donor fluorophores BTD540 and BBTD700 occurs. NIR‐II CLS can be selectively activated by hydrogen peroxide over other reactive oxygen species (ROSs). Moreover, NIR‐II CLS is capable of detecting local inflammation in mice with a 4.5‐fold higher signal‐to‐noise ratio (SNR) than that under the NIR‐II fluorescence modality. [ABSTRACT FROM AUTHOR]

Background: The m.14487T>C mutation is recognized as a diagnostic mutation of mitochondrial disease during the past 16 years, emerging evidence suggests that mutant loads of m.14487T>C and disease phenotype are not closely correlated. Methods: Immortalized lymphocytes were generated by coculturing the Epstein–Barr virus and lymphocytes from m.14487T>C carrier Chinese patient with Leigh syndrome. Fifteen cytoplasmic hybrid (cybrid) cell lines were generated by fusing mtDNA lacking 143B cells with platelets donated by patients. Mitochondrial function was systematically analyzed at transcriptomic, metabolomic, and biochemical levels. Results: Unlike previous reports, we found that the assembly of mitochondrial respiratory chain complexes, mitochondrial respiration, and mitochondrial OXPHOS function was barely affected in cybrid cells carrying homoplastic m.14487T>C mutation. Mitochondrial dysfunction associated transcriptomic and metabolomic reprogramming were not detected in cybrid carrying homoplastic m.14487T>C. However, we found that mitochondrial function was impaired in patient‐derived immortalized lymphocytes. Conclusion: Our data revealed that m.14487T>C mutation is insufficient to cause mitochondrial deficiency; additional modifier genes may be involved in m.14487T>C‐associated mitochondrial disease. Our results further demonstrated that a caution should be taken by solely use of m.14487T>C mutation for molecular diagnosis of mitochondrial disease. [ABSTRACT FROM AUTHOR]

La‐doped mesoporous γ‐alumina supported Ni oxides (xLa@NiO/γ‐MA) were prepared through one‐pot hydrolysis of inorganic salts, without the need for surfactants as in conventional practice. The catalysts were studied in the pre‐reforming of propane at a low steam to carbon molar ratio of 0.7. The results showed that the addition of La could promote the uniform dispersion of Ni species with reduced crystallite sizes, improving the catalytic properties. The 10La@Ni/γ‐MA catalyst (10 wt % La) exhibited the highest catalytic activity and excellent stability without carbon deposition for 150 hrs time‐on‐stream at 350 °C. This could be attributed to the presence of ultrafine Ni nanoparticles with an average metal particle size of 2.3 nm. Meanwhile, the doped La can donate electrons to the metallic Ni surface, preventing it from being oxidized. A minimum La/Ni atomic ratio of 1/11 (10 wt % La) was found to maintain the Ni antioxidation stability. [ABSTRACT FROM AUTHOR]

Long non‐coding RNAs (lncRNAs) have shown critical roles in multiple cancers via competitively binding common microRNAs. miR‐214 has been proved to play tumour suppressive roles in various cancers, including cervical cancer. In this study, we identified that lncRNA LINC01535 physically binds miR‐214, relieves the repressive roles of miR‐214 on its target EZH2, and therefore up‐regulates EZH2 protein expression. Intriguingly, we also found that EZH2 directly represses the expression of miR‐214. Thus, miR‐214 and EZH2 form double negative regulatory loop. Through up‐regulating EZH2, LINC01535 further represses miR‐214 expression. Functional experiments showed that enhanced expression of LINC01535 promotes cervical cancer cell growth, migration and invasion in vitro and cervical cancer xenograft growth in vivo. Reciprocally, LINC01535 knockdown suppresses cervical cancer cell growth, migration and invasion. Activation of the miR‐214/EZH2 regulatory loop by overexpression of miR‐214 or silencing of EZH2 reverses the roles of LINC01535 in promoting cervical canc'er cell growth, migration and invasion in vitro and cervical cancer xenograft growth in vivo. Clinically, LINC01535 is significantly up‐regulated in cervical cancer tissues and correlated with advanced clinical stage and poor prognosis. Moreover, the expression of LINC01535 is reversely associated with the expression of miR‐214 and positively associated with the expression of EZH2 in cervical cancer tissues. In conclusion, this study reveals that LINC01535 promotes cervical cancer progression via repressing the miR‐214/EZH2 regulatory loop. [ABSTRACT FROM AUTHOR]

Background: Medium‐chain acyl‐coenzyme A dehydrogenase deficiency (MCADD) is a rare autosomal recessive disorder that affects the degradation of medium‐chain fatty acids. Few cases of MCADD have been documented to date in mainland China. Methods: Medium‐chain acyl‐coenzyme A dehydrogenase deficiency was diagnosed in six patients (three girls and three boys) from six unrelated Chinese families at ages ranging from 10 days to 3 years old. The diagnosis was confirmed by the identification of a primary biomarker of serum octanoyl‐carnitine (C8) and genetic pathogenic mutations. Results: Only two patients were admitted because of vomiting, diarrhea, myasthenia, and coma; the other four patients were diagnosed via the newborn screening process. Six mutations were found in acyl‐CoA dehydrogenase medium chain (ACADM). One mutation (c.727C>T) was novel and the others (c.158G>A, c.387+1delG, c.449_452del, c.1045C>T, and c.1085G>A) have been previously reported. Conclusions: Six Chinese cases of MCADD were identified. One novel mutation was found. c.449_452del and c.1085G>A were common mutations in this study. [ABSTRACT FROM AUTHOR]

Background: National coverage of neonatal screening for hyperphenylalaninaemia (HPA) in China is still low and tests to differentiate causes of HPA are not performed in many centres. This study aimed to describe the demographics, geographic distribution, diagnosis, treatment and clinical outcomes of treatment, including intellectual development, in patients with tetrahydrobiopterin (BH) deficiency in mainland China. Methods: This was a retrospective, multicentre, chart review in patients with BH deficiency across mainland China born 1985-2010. Results: Two hundred fifty six patients were included; 59.9 % (267/446) of parents were from eastern China. Median (interquartile range) age at diagnosis decreased from 12.0 (5.5, 102.0) months to 2.0 (1.0, 3.5) months in patients born 1985-1999 ( n = 28) and 2005-2010 ( n = 152), respectively. 6-Pyruvoyl-tetrahydropterin synthase (PTPS) deficiency was the primary cause of BH deficiency (96.0 %); four hotspot mutations accounted for 76.6 % of PTS gene mutations; two novel variants in the QDPR gene were identified. Most patients (83.6 %) received treatment with BH, l-dopa, 5-hydroxytryptophan and/or diet therapy. Target blood Phe concentration was confirmed at 88.9 % of visits; median (Q1, Q3) blood Phe concentration was 106.8 (73.0, 120.0) μmol/L during therapy and 117.0 (67.1, 120.0) μmol/L at last visit. Median (Q1, Q3) WISC IQ score was 80.0 (69.0, 90.0) in 33 patients. DQ scores were within normal range (≥85) for 37/59 (62.7 %) patients. Physical development indicators were within normal ranges. Treatment-related adverse events, reported in 20/256 (7.8 %) patients, were mild-to-moderate in severity. Conclusion: This study provides valuable information on the current and historical situation of BH deficiency in mainland China. [ABSTRACT FROM AUTHOR]

Abstract: The most common inborn error of cobalamin (cbl) metabolism in China is the cblC type characterized by combined methylmalonic acidemia and hyperhomocysteinemia. The clinical presentation is relatively nonspecific, such as feeding difficulty, recurrent vomiting, hypotonia, lethargy, seizures, progressive developmental delay, and mental retardation, together with anemia and metabolic acidosis. More specific biochemical findings include high levels of propionylcarnitine (C3), free carnitine (C3/C0), and acetylcarnitine (C3/C2) measured by tandem mass spectrometry (MS/MS), elevation of methylmalonic acid (MMA) measured by gas chromatography–mass spectrometry (GC‐MS), and increased total homocysteine with normal or decreased methionine. We report on 50 Chinese patients with combined methylmalonic acidemia and hyperhomocysteinemia. Forty‐six belonged to the cblC complementation group. Mutation analysis of the MMACHC gene was performed to characterize the mutational spectrum of cblC deficiency, and 17 different mutations were found. Most were clustered in exons 3 and 4, accounting for 91.3% of all mutant alleles. Two mutations were novel, namely, c.315 C>G (p.Y105X) and c.470 G>C(p.W157S). In terms of genotype–phenotype correlation, the c.609 G>A mutation was associated with early‐onset disease when homozygous. Unlike previous reports from other populations, c.609 G>A (p.W203X) was the most frequent cblC mutation detected in our study of Chinese patients #Affecting 51 of 92 MMACHC alleles (55.4%). The high prevalence of this nonsense mutation could have potential therapeutic significance for Chinese cblC patients. Besides traditional approaches consisting of hydroxocobalamin injections, carnitine, betaine, and protein restriction, novel drugs that target premature termination codons may have a role in the future. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the degradation behavior of zinc oxide-glass fiber-unsaturated polyester composite exposed to a metal halide lamp. Results of the study showed that the carbonyl group on the surface was influenced by ultraviolet (UV) photons. According to the study, the carbonyl content can also decrease due to zinc oxide. It also found that photo-initiated oxidation was the major reaction of pure unsaturated polyester under UV exposure.

ZnO-glass fiber-unsaturated polyester composites have been prepared. On exposure to the metal halide lamp, their resistance to ultraviolet (UV) degradation is evaluated. Experimental results show that ZnO can reduce the UV degradation of the unsaturated polyester matrix. ZnO can significantly retard the UV degradation process of the matrix resin, and can also increase the impact strength of the composites under the experimental conditions. Differential scanning calorimetry (DSC) analyses also indicate that the addition of ZnO to unsaturated polyester may retard the crosslink process and catalyze the decomposition of the resin. However, after more than 40 hr of UV irradiation, it was crosslinked. SEM fracture morphology shows that nano ZnO could hinder crack growth and induce more cracks, and when the content of ZnO reaches 6 wt%, the impact fracture mechanism changes abruptly and plastic deformation appears, which indicates that 6 wt% for ZnO in unsaturated polyester could be considered as the critical content. Around the critical content, the particles are near enough to interact with each other and this results in the change of fracture mechanism. The results also indicate that the proper content of ZnO added into an unsaturated polyester could prolong the durability and lessen the reject rate of transparent glass fiber-polyester composites. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study focuses on the effectiveness of calcium (Ca2+) improving ferric (hydro)oxides precipitation and its subsequent effects on arsenic co-precipitation with ferric (hydro)oxides. The effects of Ca2+ on surface charge characteristics and precipitating behavior, which are respectively represented as zeta (ζ) potential and RPDA, are investigated for ferric (hydro)oxides precipitates. The presence of Ca2+ increases the ζ potential of ferric (hydro)oxides, and a more significant effect is observed at higher pH conditions. Calcium apparently facilitates ferric (hydro)oxide floc aggregation, increasing the maximum RPDA from 3.19 to 5.27% (in the presence of 3.5 mg/L silicate as silicon). These positive effects contribute to reduce the adverse effects resulting from the presence of silicate and enhance arsenic removal via ferric (hydro)oxides co-precipitation under different conditions. Furthermore, the effect of Ca2+ facilitating ferric precipitation (and therefore providing more precipitated solids for arsenic) is predominant in favoring arsenic removal compared with that of increasing surface charge. Calcium plays an important role in arsenic co-precipitation with ferric (hydro)oxides in the presence of silicate. Water Environ. Res., 79, 2260 (2007). [ABSTRACT FROM AUTHOR]