A pomegranate seed-structured nanozyme-based colorimetric immunoassay for highly sensitive and specific biosensing of Staphylococcus aureus.

Staphylococcus aureus (S. aureus) infections are a serious threat to human health. The development of rapid and sensitive detection methods for pathogenic bacteria is crucial for accurate drug administration. In this research, by combining the advantages of enzyme-linked immunosorbent assay (ELISA), we synthesized nanozymes with high catalytic performance, namely pomegranate seed-structured bimetallic gold-platinum nanomaterials (Ps-PtAu NPs), which can catalyze a colorless TMB substrate into oxidized TMB (oxTMB) with blue color to achieve colorimetric analysis of S. aureus. Under the optimal conditions, the proposed biosensor could quantitatively detect S. aureus at levels ranging from 1.0 × 101 to 1.0 × 106 CFU mL-1 with a limit of detection (LOD) of 3.9 CFU mL-1. Then, an integrated color picker APP on a smartphone enables on-site point-of-care testing (POCT) of S. aureus with LOD as low as 1 CFU mL-1. Meanwhile, the proposed biosensor is successfully applied to the detection of S. aureus in clinical samples with high sensitivity and specificity.

Overcoming Charge Confinement in Perovskite Nanocrystal Solar Cells.

The small nanoparticle size and long-chain ligands in colloidal metal halide perovskite quantum dots (PeQDs) cause charge confinement, which impedes exciton dissociation and carrier extraction in PeQD solar cells, so they have low short-circuit current density Jsc , which impedes further increases in their power conversion efficiency (PCE). Here, a re-assembling process (RP) is developed for perovskite nanocrystalline (PeNC) films made of colloidal perovskite nanocrystals to increase Jsc in PeNC solar cells. The RP of PeNC films increases their crystallite size and eliminates long-chain ligands, and thereby overcomes the charge confinement in PeNC films. These changes facilitate exciton dissociation and increase carrier extraction in PeNC solar cells. By use of this method, the gradient-bandgap PeNC solar cells achieve a Jsc = 19.30 mA cm-2 without compromising the photovoltage, and yield a high PCE of 16.46% with negligible hysteresis and good stability. This work provides a new strategy to process PeNC films and pave the way for high performance PeNC optoelectronic devices.

Bioinspired, Anticoagulative, 19 F MRI-Visualizable Bilayer Hydrogel Tubes as High Patency Small-Diameter Vascular Grafts.

The clinical patency of small-diameter vascular grafts (SDVGs) (ID < 6 mm) is limited, with the formation of mural thrombi being a major threat of this limitation. Herein, a bilayered hydrogel tube based on the essential structure of native blood vessels is developed by optimizing the relation between vascular functions and the molecular structure of hydrogels. The inner layer of the SDVGs comprises a zwitterionic fluorinated hydrogel, avoiding the formation of thromboinflammation-induced mural thrombi. Furthermore, the position and morphology of the SDVGs can be visualized via 19 F/1 H magnetic resonance imaging. The outer poly(N-acryloyl glycinamide) hydrogel layer of SDVGs provides matched mechanical properties with native blood vessels through the multiple and controllable intermolecular hydrogen-bond interactions, which can withstand the accelerated fatigue test under pulsatile radial pressure for 380 million cycles (equal to a service life of 10 years in vivo). Consequently, the SDVGs exhibit higher patency (100%) and more stable morphology following porcine carotid artery transplantation for 9 months and rabbit carotid artery transplantation for 3 months. Therefore, such a bioinspired, antithrombotic, and visualizable SDVG presents a promising design approach for long-term patency products and great potential of helping patients with cardiovascular diseases.

Transport Layer Engineering Toward Lower Threshold for Perovskite Lasers.

Charge-transport layers are essential for achieving electrically pumped perovskite lasers. However, their role in perovskite lasing is not fully understood. Here, the role of charge-transport layers on the lasing actions of perovskite films is explored by investigating the amplified spontaneous emission (ASE) thresholds. A largely reduced ASE threshold and enhanced ASE intensity is demonstrated by introducing an additional hole transport layer poly(triaryl amine) (PTAA). It is shown that the key role of the PTAA layer is to accelerate the hot-carrier cooling process by extracting holes in perovskites. With reduced hot holes, the Auger recombination loss is largely suppressed, resulting in decreased ASE threshold. This argument is further supported by the fact that the ASE threshold can be further reduced from 25.7 to 7.2 µJ cm-2 upon switching the pumping wavelength from 400 to 500 nm to directly avoid excess hot-hole generation. This work exemplifies how to further reduce the ASE threshold with transport layer engineering through hot-hole manipulation. This is critical to maintaining the excellent gain properties of perovskites when integrating them into electrical devices, paving the way for electrically pumped perovskite lasers.

Overexpression of CASC19 contributes to tumor progression and predicts poor prognosis after radical resection in hepatocellular carcinoma.

BACKGROUND: Long non-coding RNAs (lncRNAs) have been implicated as functional molecules in hepatocellular carcinoma (HCC) progression. The present research aimed to investigate the levels of LncRNA cancer susceptibility candidate gene 19 (CASC19) in HCC tissues and cell lines and to explore its potential role in the diagnosis and prognosis of HCC. METHODS: HCC tissues and cell lines were collected to assess the levels of CASC19 by real-time quantitative reverse transcription PCR (RT-qPCR). The prognostic value of CASC19 was evaluated using the Kaplan-Meier method and Cox regression analysis. The functional role of CASC19 in regulating HCC cell proliferation, migration, and invasion was evaluated by Cell Counting Kit-8 (CCK-8) and Transwell analysis. The potential targeted miR-140-5p of CASC19 was confirmed by a dual-luciferase reporter assay. RESULTS: High CASC19 expression positively correlated with tumor size, differentiation, and TNM stage in HCC patients (P < 0.05). Patients with high CASC19 expression have a poorer survival prognosis and are prone to relapse compared to those with low CASC19. miR-140-5p, a target miRNA for CASC19, negatively correlated with CASC19 levels in tumor tissues. Reduced CASC19 levels attenuated cell proliferation, migration, and invasion, but this attenuation was reversed by suppression of miR-140-5p. CONCLUSION: Up-regulated CASC19 may serve as a biomarker for predicting poor prognosis in HCC patients. In vitro, overexpressed CASC19 promoted the progression of HCC, indicating that CASC19 may be a possible therapeutic target for the treatment of HCC.

Totally thoracoscopic surgery for treating left atrial myxoma.

ABSTRACT: We aimed to summarize the experience of totally thoracoscopic surgery for left atrial myxoma, together with analyzing the safety and feasibility. We retrospectively analyzed the clinical data of 15 patients with left atrial myxoma admitted to our hospital from October 2016 to October 2018. The auxiliary hole was located at the midline of the 5th intercostal space of the right chest. The endoscope hole was located at the front position of the fourth intercostal space. Specimens were sent to the pathology department for pathological examination. All the procedures were completed successfully. Extracorporeal circulation time was 46.5 ±â€Š18.6 minute, cross-clamping time was 20.6 ±â€Š6.7 minute, thoracic drainage fluid was 89+60.2 ml, ventilator assist time was 4.3 ±â€Š2.6 hour, intensive care unit stay time was 14.5 ±â€Š4.2 hour, the average postoperative hospital stay was 5.2 ±â€Š1.2 day. There was no death, or red blood cell transfusion during and after surgery. No postoperative complications were reported by the patients. No recurrence of myxoma, residual shunt in the atrial septum and valvular lesions were found after 3months of postoperative cardiac ultrasound examination. Total thoracoscopic surgery for left atrial myxoma was less invasive with satisfactory cosmetic appearance with feasibility and safety. Besides, it caused no serious complications.

Total thoracoscopic surgery for biatrial cardiac myxoma: a case report.

Myxoma is the most common type of benign cardiac tumor in adults. Myxoma can occur anywhere in the heart. The left atrium is the most frequent site of origin, specifically located on the left atrium side of the fossa oval in the atrial septum, followed by the right atrium, the right ventricle and left ventricle. But biatrial myxoma is extremely rare. Thoracoscopic resection of myxoma has become more common, but there are few reports on thoracoscopic surgery for biatrial myxoma. We present a case of a 72-year-old woman with biatrial myxoma, who presented with intermittent dyspnea for one week. Echocardiography revealed a medium echo in both the left and right atrium and was connected via the atrial septum. Computed tomography revealed a hypointense mass in both atria. Thoracoscopic resection successfully removed the tumors, and histological examination confirmed the diagnosis. Also, the patient was discharged six days after surgery. There was no evidence of tumor recurrence during the one-year follow-up period. Biatrial myxoma is rare. Surgical resection is the primary method for myxoma. Compared with the traditional medium thoracotomy, thoracoscopic surgery for myxoma has the following advantages: less trauma, keeping the integrity of the sternum, less bleeding, faster postoperative recovery, etc. Total thoracoscopic surgery for biatrial myxomas is effective and safe.

Reaching the limits of reciprocity in favor exchange: The effects of generous, stingy, and matched favor giving on social status.

Group members gain social status via giving favors to others, but why and when they do so remain unclear in the literature. Building on social exchange theory and social status literature, we identify three types of favor giving among group members (generous, stingy, and matched) and propose that an affective mechanism (i.e., gratitude) and a cognitive mechanism (i.e., perceived competence) underlie the relationship between favor giving and status attainment. Specifically, generous/stingy favor giving has a linear relationship with status attainment through both gratitude and perceived competence, whereas matched favor giving has a curvilinear relationship with status attainment only through perceived competence. An experimental study and a field study lend support to our propositions. Our study complements the literature by offering a complete picture of how three types of favor giving among group members shape their social status in different ways. (PsycINFO Database Record