Ag@Pyc Nanocapsules as Electrochemiluminescence Emitters for an Ultrasensitive Assay of the APE1 Activity.

Herein, Ag@pyrenecarboxaldehyde nanocapsules (Ag@Pyc nanocapsules) as emitters were prepared to construct an ultrasensitive electrochemiluminescence (ECL) biosensor for the detection of the human apurinic/apyrimidinic endonuclease1 (APE1) activity. Ag nanoparticles on the surface of Pyc nanocapsules as coreaction accelerators could significantly promote coreactant peroxydisulfate (S2O82-) to generate massive reactive intermediates of sulfate radical anion (SO4•-), which interacted with the Pyc nanocapsules to achieve a strong ECL response. In addition, with the aid of APE1-triggered 3D DNA machine, trace target could be converted into a large number of mimic targets (MTs), which were positively correlated with the activity of APE1. Consequently, the proposed ECL biosensor realized an ultrasensitive detection of APE1 activity with an exceptional linear working range from 5 × 10-10 to 5 × 10-4 U·µL-1 and a lower limit of detection of 1.36 × 10-11 U·µL-1. This strategy provided a new approach to construct an efficient ternary system for the detection of biomolecules and early diagnosis of diseases.

Downregulation of LAPTM4B Contributes to the Impairment of the Autophagic Flux via Unopposed Activation of mTORC1 Signaling During Myocardial Ischemia/Reperfusion Injury.

RATIONALE: Impaired autophagic flux contributes to ischemia/reperfusion (I/R)-induced cardiomyocyte death, but the underlying molecular mechanisms remain largely unexplored. OBJECTIVE: To determine the role of LAPTM4B (lysosomal-associated transmembrane protein 4B) in the regulation of autophagic flux and myocardial I/R injury. METHODS AND RESULTS: LAPTM4B was expressed in murine hearts but downregulated in hearts with I/R (30 minutes/2 hours) injury and neonatal rat cardiomyocytes with hypoxia/reoxygenation (6 hours/2 hours) injury. During myocardial reperfusion, LAPTM4B-knockout (LAPTM4B-/-) mice had a significantly increased infarct size and lactate dehydrogenase release, whereas adenovirus-mediated LAPTM4B-overexpression was cardioprotective. Concomitantly, LAPTM4B-/- mice showed higher accumulation of the autophagy markers LC3-II (microtubule-associated protein 1A/1B-light chain 3), but not P62, in the I/R heart, whereas they did not alter chloroquine-induced further increases of LC3-II and P62 in both sham and I/R hearts. Conversely, LAPTM4B-overexpression had opposite effects. The hypoxia/reoxygenation-reduced viability of neonatal rat cardiomyocytes, ratio of autolysosomes/autophagosomes, and function of lysosomes were further decreased by LAPTM4B-knockdown but reversed by LAPTM4B-overexpression. Moreover, the LAPTM4B-overexpression-mediated benefits were abolished by knockdown of lysosome-associated membrane protein-2 (an autophagosome-lysosome fusion protein) in vivo and by the autophagy inhibitor bafilomycin A1 in vivo. In contrast, rapamycin (Rapa) successfully restored the impaired autophagic flux in LAPTM4B-/- mice and the subsequent myocardial I/R injury. Mechanistically, LAPTM4B regulated the activity of mTORC1 (mammalian target of rapamycin complex 1) via interacting with mTOR through its EC3 (extracelluar) domain. Thus, mTORC1 was overactivated in LAPTM4B-/- mice, leading to the repression of TFEB (transcription factor EB), a master regulator of lysosomal and autophagic genes, during myocardial I/R. The mTORC1 inhibition or TFEB-overexpression rescued the LAPTM4B-/--induced impairment in autophagic flux and I/R injury, whereas TFEB-knockdown abolished the LAPTM4B-overexpression-mediated recovery of autophagic flux and cardioprotection. CONCLUSIONS: The downregulation of LAPTM4B contributes to myocardial I/R-induced impairment of autophagic flux via modulation of the mTORC1/TFEB pathway. Graphic Abstract: A graphic abstract is available for this article.

Supersensitive Photoelectrochemical Aptasensor Based on Br,N-Codoped TiO2 Sensitized by Quantum Dots.

Here, we fabricated a novel photoelectrochemical (PEC) aptasensor based on Br,N-codoped TiO2/CdS quantum dots (QDs) sensitization structure with excellent energy level arrangement for supersensitive detection of carcinoembryonic antigen (CEA). The prepared Br,N-codoped TiO2 could reduce the energy bandwidth of TiO2 from 3.2 to 2.88 eV, which could dramatically reduce the basic signal and obviously broaden the absorption of light (400-700 nm). In addition, the energy bandwidth of Br,N-codoped TiO2 (2.88 eV) matched well with that of CdS QDs (2.4 eV), making CdS QDs an ideal signal enhancer for amplifying the photocurrent signal of Br,N-codoped TiO2. More importantly, the constructed Br,N-codoped TiO2/CdS QDs sensitization structure with narrow energy level gradient enabled the effective promotion of electron-transfer capability and dramatic improvement of photoelectric conversion efficiency. Simultaneously, a small amount of the CEA was transformed into substantial single-chain DNA (T-DNA) via exonuclease III (Exo-III)-assisted cycle strategy. Under optimum conditions, the designed PEC aptasensor demonstrated a wide detection range from 1 fg/mL to 1 ng/mL and a low detection limit as 0.46 fg/mL for CEA assay. This strategy prepared a new photoactive material to markedly improve photoelectric conversion efficiency and initiated a new way to realize the highly sensitive PEC biomolecules detection.

Cosensitization Strategy with Cascade Energy Level Arrangement for Ultrasensitive Photoelectrochemical Protein Detection.

Here, a photoelectrochemical (PEC) biosensor was established by a cosensitization strategy with cascade energy level arrangement for ultrasensitive detection of prostate-specific antigen (PSA). The proposed cosensitization strategy was based on the well-matched energy level arrangement of four kinds of organic photoactive materials, in which poly{4,8-bis[5-(2-ethylhexyl)thiophen-2-yl]benzo[1,2- b:4,5- b']dithiophene-2,6-diyl- alt-3-fluoro-2-[(2-ethylhexyl)-carbonyl]thieno[3,4- b]thiophene-4,6-diyl} (PTB7-Th) was used as the photoactive material and perylenetetracarboxyl diimide (PDI), fullerene (nano-C60), and polyaniline (PANI) were employed as the sensitizers. The resulting PTB7-Th/PDI/nano-C60/PANI cascade cosensitization structure with narrow energy level gradient (<0.54 eV) could effectively improve electron transfer capability, obviously raise light energy utilization and significantly enhance photoelectric conversion efficiency, leading to dramatically enhanced photocurrent response. Using PSA as a target model, the proposed PEC biosensor exhibited high sensitivity and excellent stability with a wide detection range from 1 fg/mL to 0.1 ng/mL and a detection limit of 0.43 fg/mL. Moreover, the proposed PEC biosensor provides a cascade cosensitization strategy that could significantly improve PEC performances and open up a promising platform to establish high selectivity, stability, and ultrasensitive analytical techniques.

[The Risk Factors of Contralateral Central Lymph Node Metastasis in Solitary Thyroid Papillary Micro-carcinoma].

OBJECTIVE: To explore the possible risk factors of contralateral central lymph node metastasis (CLNM) in solitary thyroid papillary micro-carcinoma (PTMC). METHODS: Clinicopathologic data of 318 patients with confirmed solitary PTMC by final histological who underwent bilateral centeral lymph node dissection (CLND) from April 2012 to May 2015 in our hospital were retrospectively reviewed. Univariate Χ2 test and multivariate logistic regression analysis were used to determine the risk factors of contralateral CLNM in solitary PTMC. RESULTS: The incidence of ipsilateral CLNM and contralateral CLNM in solitary PTMC patients were 40.57% (129/318), 9.75% (31/318), respectively. Univariate analyses revealed that contralateral CLNM had a correlation with tumor located in lower pole, capsular invasionand underlying ipsilateral CLNM (P < 0.05), and had a correlation with underlying nodular goiter (P < 0.05). Multivariate logistic regression analysis showed that tumor located in lower pole and ipsilateral CLNM were independent risk factors for contralateral CLNM (P < 0.05). CONCLUSIONS: Solitary PTMC patients had a low tendency to contralateral CLNM, it shouldn't undergo contralateral CLND commonly, if the tumor located in lower pole or combine withipsilateral CLNM, it should be consider to undergo bilateral CLND.

Pyrenecarboxaldehyde@Graphene Oxide Acted as a Highly Efficient ECL Emitter and Target-Triggered the Recyclable Cascade System as an Amplifier for Ultrasensitive APE1 Activity Detection.

Herein, pyrenecarboxaldehyde@graphene oxide (Pyc@GO) sheets with highly efficient electrochemiluminescence (ECL) as emitters were prepared by a noncovalent combination to develop a neoteric ECL biosensing platform for the ultrasensitive assessment of human apurinic/apyrimidinic endonuclease1 (APE1) activity. Impressively, the pyrenecarboxaldehyde (Pyc) molecules were able to form stable polar functional groups on the surface of GO sheets through the noncovalent π-π stacking mechanism to prevent intermolecular restacking and simultaneously generate Pyc@GO sheets. Compared with the tightly packed PAH nanocrystals, the Pyc@GO sheets significantly reduced internal filtering effects and diminished nonactivated emitters to enhance ECL intensity and achieve strong ECL emission. Furthermore, the APE1-activated initiators could trigger the recyclable cascade amplified system based on the synergistic cross-activation between catalytic hairpin assembly (CHA) and DNAzyme, which improved the signal amplification and transduction ability. Consequently, the developed ECL platform for the detection of APE1 activity displayed exceptional sensitivity with a low detection limit of 4.6 × 10-9 U·mL-1 ranging from 10-8 to 10-2 U·mL-1. Therefore, the proposed strategy holds great promise for the future development of sensitive and reliable biosensing platforms for the detection of various biomarkers.

[Multicentric randomized double blinded clinical study of Yiqi Tongmai Oral Liquid against angina pectoris in patients with coronary heart disease].

OBJECTIVE: To study the efficacy and safety of Yiqi Tongmai Oral Liquid (YQTM), a traditional compound Chinese herbal medicine, in treating angina pectoris in patients with coronary heart disease. METHODS: A multicentric, randomized, double blinded and paralleled controlled trial was conducted on 110 patients in trial group treated with YQTM, and 109 patients in control group treated with Shuxin Oral Liquid (SX). Cure and effective rates in both groups were evaluated. Frequency and duration of angina attack were counted and measured. Coronary angiography (CAG), electrocardiogram (ECG) and flat exercise test were taken in both groups. Blood lipid indexes, such as cholesterol (CH), triglyceride (TG), low-density lipoprotein (LDL), high density lipoprotein (HDL), were determined at pre- and post-treatment. The hemodynamic indexes, such as whole blood viscosity (J2), high-shear reduced viscosity (Eh), low-shear reduced viscosity (Ei), red cell aggregation index (Lb), red cell rigidity index (Rh), fibrinogen (Fb), blood sedimentation rate (BSR) and hematocrit (HCT), were determined at pre-and post-treatment. The indicated scores of symptoms and signs of traditional Chinese medicine (TCM) pattern, such as chest pain, chest constriction, breath shortness, palpitation, fatigue, dim complexion, spontaneous perspiration and tongue proper, tongue coating were evaluated in week 0, 1, 2, 3, 4 during the treatment course. The safety indexes, such as body temperature, pulse, respiration and blood pressure were observed. Routine tests of blood, urine and stool, hepatic function test and renal function test were taken at pre- and post-treatment. RESULTS: There was no significant difference between the total effective rate of the trial group and that of the control group, which were 91.82% and 85.32%, respectively (P>0.05). Trial groups percentile of cure rate is significantly higher than that of the control group (P<0.01). The frequency and duration of angina attack, the positive ratio of CAG and flat exercise test of both groups were lowered, while the effect of the trial group on frequency and duration of angina attack was better. No significant difference was found in ECG features between the two groups (P>0.05). The levels of CH, TG and LDL of both groups were lowered significantly (P<0.05). The effect of lowering CH, TG and LDL of the trial group was stronger than that of the control group (P<0.05). The hemodynamic indexes, such as J2, Eh, Ei, Lb, Rh, Fb, BSR and HCT were improved significantly in both groups (P<0.05). The improvements of J2, Eh, Ei, Lb, Rh, Fb and SR in the trial group were greater than those of control group (P<0.05). The TCM symptoms and signs, such as chest pain, chest constriction, breath shortness, palpitation, fatigue, dim complexion, spontaneous perspiration were improved significantly in both groups (P<0.05). The improvements of chest constriction, palpitation, fatigue and spontaneous perspiration in the trial group were greater than those of the control group (P<0.05). The total indicated score of TCM symptoms and signs was lowered more significantly than that of the control group (P<0.01). No significant changes were found at pre- and post-treatment in safety indexes, such as routine tests for blood, urine and stool, hepatic function test and renal function test. There was no significant difference in safety features of both groups (P>0.05). CONCLUSION: Yiqi Tongmai Oral Liquid bears good therapeutic effect on angina pectoris without adverse reaction, and is superior to Shuxin Oral Liquid. Yiqi Tongmai Oral Liquid is a new effective and safe medicine for the treatment of angina pectoris in patients with coronary heart disease.