Ratiometric determination of etomidate based on an albumin-based indicator displacement assay (IDA)

The first fluorescent sensor based on the indicator displacement assay (IDA) for on-site determination of etomidate.

Kinetic Process with Anti-Frenkel Disorder in a CsPbI3 Perovskite

Halide perovskites are rich in ionic diffusion phenomena due to their low activation energy. The soft lead iodide lattice can, in theory, endow the system with more complex defect collaborative motions. In this work, we systematically investigated the hopping mechanics of iodide interstitials with respect to various defect behaviors, such as anti-Frenkel disorder creation and annihilation. We found that the existence of iodide vacancies and interstitials can effectively lower the creation barrier of additional anti-Frenkel disorder in the halide perovskite. The free energy barriers for generating additional Frenkel defect pairs vary from 0.25 to 0.43 eV, in the proximity of those of the original iodide defects at 300 K. This finding suggests that the spontaneous creation of a specific level of anti-Frenkel disorder facilitates long-range annihilation and defect hopping processes.

A ratiometric fluorescent indicator-displacement assay for on-site determination and intracellular imaging of nitroxinil

Nitroxinil (NIT) is a widely using veterinary medicine to protect cattle and sheep yet may threaten human health when ingested through food chain. Developing fluorescent analytical methods in ratiometric manners was essential for the on-site detection and in-situ monitoring of NIT but still challenging. Here, we improved the indicator-displacement assay (IDA)-based method and designed the first ratiometric fluorescent probe for NIT by using an albumin host and an Aggregation-induced emission (AIE) guest. This probe exhibited fast response (10 s), high sensitivity (limit of detection: 4.6 ppb), good selectivity (over twelve medicines) and eye-discriminable fluorescent color change (green-red) upon responding to NIT. Based on these properties, this probe enabled quantitative determination of NIT in real food samples, on-site analysis via a paper-based test strip, and fluorescence imaging of NIT in living cells.

Rational design of a FA1-targeting anti-interference fluorescent probe for the point-of-care testing of albuminuria

Albuminuria is a crucial urine biomarker of human unhealthy events such as kidney diseases, cardiovascular diseases, and diabetes. However, the accurate diagnosis of albuminuria poses a significant challenge owing to the severe interference from urine fluorescence and urine drugs. Here, we report a novel flavone-based fluorescent probe, DMC, by incorporating the FA1-targeting methylquinazoline group into a flavone skeleton with the extend π-conjugation. DMC exhibited a rapid response time, high sensitivity, and selectivity towards human serum albumin (HSA) in urine. Moreover, the red-shifted fluorescence and the FA1-targeted HSA-binding of DMC efficiently mitigated the interference from both urine fluorescence and urine drug metabolites. Furthermore, the establishment of a portable testing system highlighted the potential for point-of-care testing, offering a user-friendly and accurate approach to diagnose A2-level and A3-level albuminuria. We expect that the success of this DMC-based diagnostic platform in real urine samples can signify a significant advancement in early clinical diagnosis of albuminuria and its associated diseases.

Toward stabilization of formamidinium lead iodide perovskites by defect control and composition engineering

Phase instability poses a serious challenge to the commercialization of formamidinium lead iodide (FAPbI3)-based solar cells and optoelectronic devices. Here, we combine density functional theory and machine learning molecular dynamics simulations, to investigate the mechanism driving the undesired α-δ phase transition of FAPbI3. Prevalent iodine vacancies and interstitials can significantly expedite the structural transition kinetics by inducing robust covalency during transition states. Extrinsically, the detrimental roles of atmospheric moisture and oxygen in degrading the FAPbI3 perovskite phase are also rationalized. Significantly, we discover the compositional design principles by categorizing that A-site engineering primarily governs thermodynamics, whereas B-site doping can effectively manipulate the kinetics of the phase transition in FAPbI3, highlighting lanthanide ions as promising B-site substitutes. A-B mixed doping emerges as an efficient strategy to synergistically stabilize α-FAPbI3, as experimentally demonstrated by substantially higher initial optoelectronic characteristics and significantly enhanced phase stability in Cs-Eu doped FAPbI3 as compared to its Cs-doped counterpart. This study provides scientific guidance for the design and optimization of long-term stable FAPbI3-based solar cells and other optoelectronic devices through defect control and synergetic composition engineering.

Fluorescence determination of the total amount of tetracyclines by a flavonol-based supramolecular sensor

Tetracyclines (TCs) are a group of broad-spectrum antibiotics against multiplying microorganisms yet with several adverse effects on humans. Since all types of TCs have the similar chemical skeleton and mechanism of action, quantification of total amount of TCs in the environment was of particular importance. To date, dozens of fluorescent probes have been reported for TCs detection, but only very few of them enabled detection of total TCs. In this study, we report a novel supramolecular sensor constructed by human serum albumin as the recognition moiety and a flavonol fluorophore as the indicator. Under the 370 nm UV excitation, this sensor exhibits the rapid response (5 s), acceptable sensitivity (limit of detection ∼ 0.58 μM), long dynamic detection range (0-20 μM), prominent specificity, and excellent anti-interference properties for analysis of total TCs. The mechanism was carefully validated using 1H NMR, fluorescence titration experiments, molecular docking, and mass spectrometry. We expect this work can inspire more sensor design for TCs quantification.

A comparison of radiofrequency Coblation and cold steel excision in the treatment of idiopathic vocal process granulomas

OBJECTIVE

To compare the effectiveness of radiofrequency Coblation assisted excision and cold steel excision in the treatment of idiopathic vocal process granulomas.

METHODS

A retrospective study was performed of patients with idiopathic vocal process granulomas who underwent radiofrequency Coblation excision or cold steel excision between January 2013 and January 2020. The recurrence rate was compared among the two groups at six months post-operatively.

RESULTS

Of the 47 patients with vocal process granulomas, 28 were in the cold steel excision (control) group and 19 were in the Coblation-assisted group. The recurrence rate in the control group was significantly higher than that in the Coblation-assisted group (60.7 per cent vs 5.3 per cent; p < 0.001). In addition, the voice recovery of the Coblation-assisted group was significantly better than that of the control group; vocal quality recovered one month after surgery in the Coblation-assisted group.

CONCLUSION

Radiofrequency Coblation should be considered the optimal method when approaching idiopathic vocal process granulomas surgically.

Dual-mode supramolecular fluorescent probe for rapid and on-site detection of chlorpyrifos in the environment

Chlorpyrifos (CPF) as a classic organophosphorus pesticide has been widely used in agricultural applications to control insects and worms. CPF in the environment can cause deaths of diverse kinds of aquatic organism and bring a high risk to human health. Therefore, the development of effective analytical method for CPF is of great importance. In this work, a novel dual-mode albumin (ALB)-based supramolecular probe FD@ALB was designed and prepared for rapid detection of CPF in the environment. The limit of detection is 0.57 μM (∼ 0.2 ppm) with a wider detection range up to 200 μM, which is satisfactory for application. The sensing mechanism can be ascribed to CPF-induced phosphorylation of ALB, thus leading to a change in the binding microenvironment of FD dye. Moreover, the paper-based test strips were used in conjunction with the FD@ALB, realizing the portable detection of CPF. This method was demonstrated to be suitable for on-site detection of CPF in various kinds of environmental samples, including water, soil, and food samples, with the aid of a smartphone. To the best of our knowledge, this is the first analytical method achieving a combination of the rapid and ratiometric detection of CPF in the environment.

A portable paper-based testing device for fast and on-site determination of nitroxynil in food

Nitroxynil (NTX) is a common anthelmintic veterinary drug for the management of fascioliasis in food-producing sheep and cattle. Since excessive NTX residue in food can lead to several adverse side effects, such as allergic skin reaction and respiratory irritation, it is of great importance to develop an efficient analytical method for NTX determination. Herein, we report a simple fluorescent detection method based on a novel supramolecular probe capable of detecting NTX with a fast response (5 s), high sensitivity (107 nM), high selectivity, and acceptable anti-interference property. Moreover, the portable paper-based test strips were facilely prepared and successfully realized on-site determination of NTX in real edible animal products simply with the aid of a smartphone. To the best of our knowledge, this is the very first report on the portable detection of NTX. This study also provides a promising strategy for the fast and portable detection of analyte based on the host-guest system, which will lead to improved fluorescent probe design for food analysis.

Smartphone-based on-site detection of hydrogen peroxide in milk by using a portable ratiometric fluorescent probe

The on-site detection of hydrogen peroxide (H₂O₂) is important for maintaining food safety as the ingestion of H₂O₂ can lead to serious pathological conditions. However, most reported fluorescent probes require a fluorometer to ensure readable signal output and reliable detection result. Consequently, the fluorescent detection of H₂O₂ can be realized only within a standard laboratory setting. Herein, we report a novel supramolecular strategy that can successfully convert the typical off-on response to H₂O₂ into a ratiometric response, which allows the on-site detection of H₂O₂ when used in conjunction with a smartphone-based 3D-printed miniaturized testing system. This method has acceptable sensitivity, good anti-interference ability, and desirable accuracy compared to a standard detection method. More importantly, this portable ratiometric method can be used to detect H₂O₂ residue in commercial milk samples with the simple testing apparatuses.

A dual-emissive supramolecular sensor for fast and ratiometric determination of carprofen in meat

Carprofen (CPF) is a non-steroidal anti-inflammatory drug that has been widely used in livestock for the treatment of fever and inflammation. Yet the massive use of CPF comes at the cost of its residue ubiquitous in the environment thus leading to a huge risk to human health. Therefore, development of a convenient analytical method for monitoring CPF is of considerable importance. In this study, a dual-emissive supramolecular sensor was facilely constructed using bovine serum albumin as the host and an environmentally sensitive dye as the guest. This sensor, for the first time, successfully realized the fluorescent detection of CPF with a rapid response, high sensitivity and selectivity. More importantly, this sensor exhibited a very unique ratiometric response to CPF, which endowed this method with satisfactory detection accuracy for food analysis. To the best of our knowledge, this is the first fluorescent method for fast determination of CPF in food.

The first fluorescent sensor for the detection of closantel in meat

Closantel is widely used in the management of parasitic infestation in livestock, but is contraindicated in humans due to its high toxic to human retina. Thus, development of a fast and selective method for the detection of closantel residues in animal products is highly needed yet still challenging. In the present study, we report a supramolecular fluorescent sensor for closantel detection through a two-step screening process. The fluorescent sensor can detect closantel with a fast response (<10 s), high sensitivity, and high selectivity. The limit of detection is 0.29 ppm, which is much lower than the maximum residue level set by government. Moreover, the applicability of this sensor has been demonstrated in commercial drugs tablets, injection fluids, and real edible animal products (muscle, kidney, and liver). This work provides the first fluorescence analytical tool for accurate and selective determination of closantel, and may inspire more sensor design for food analysis.

General Method for Pesticide Recognition Using Albumin-Based Host-Guest Ensembles

The massive use of pesticides nowadays has led to serious consequences for the environment and public health. Fluorescence analytical methods for pesticides are particularly advantageous with respect to simplicity and portability; however, currently available fluorescence methods (enzyme-based assays and indicator displacement assays) with poor universality are only able to detect few specific pesticides (e.g., organophosphorus). Making use of the multiple flexible and asymmetrical binding sites in albumin, we herein report a set of multicolor albumin-based host-guest ensembles. These ensembles exhibit a universal but distinctive fluorescent response to most of the common pesticides and allow array-based identification of pesticides with high accuracy. Furthermore, the simplicity, portability, and visualization of this method enable on-site determination of pesticides in a practical setting. This albumin host strategy largely expands the toolbox of traditional indicator displacement assays (synthetic macrocycles as hosts), and we expect it to inspire a series of sensor designs for pesticide detection.

Fluorescence discrimination of HSA from BSA: A close look at the albumin-induced restricted intramolecular rotation of flavonoid probe

Discrimination of human serum albumin (HSA) from bovine serum albumin (BSA) based on the fluorescence probe technique is still challenging due to similar chemical structures. In this work, a novel flavonoid-based fluorescent probe AF is reported for successful discrimination of HSA from BSA. The sensing performances of probe, including sensing dynamic, sensitivity and selectivity, have been carefully studied. Moreover, sensing mechanism was elucidated by Job's plot, displacement experiment, and molecular docking, suggesting that the specific response to HSA originated from the albumin-induced restricted intramolecular rotation (RIR) of probe. This work may provide a simple way for designing of novel probes for HSA with high selectivity.

A DS2-specific flavonoid-based probe with a unique dual-emissive response to human serum albumin

The hydroxyl substituent in flavonoids can cause the binding site to change from DS1 to DS2 and restore the ESIPT process of flavonoids, thereby leading to a unique dual-emissive response towards human serum albumin.

A new diagnostic index for sarcopenia and its association with short-term postoperative complications in patients undergoing surgery for colorectal cancer

AIM

Sarcopenia is a robust prognostic indicator of outcomes after surgery for colorectal cancer (CRC). However, there are no serum markers routinely available for estimating skeletal muscle mass (SMM). The present study aimed to describe a new sarcopenia index (SI), serum creatinine (Scr) × cystatin C-based glomerular filtration rate, and investigate its association with short-term complications after curative resection of CRC.

METHOD

Consecutive patients who underwent curative resection of CRC from December 2011 to January 2017 were retrospectively identified. Skeletal muscle cross-sectional area was analysed on L3 computed tomographic images. Receiver operating characteristic curve analysis showed that the cutoff points of SI for sarcopenia were below 56.1 in men and below 43.7 in women. Patients were classified into low and high SI groups in accordance with these cutoff values. The association between SI and body composition and the impact of preoperative SI on postoperative outcomes were analysed.

RESULTS

Among 417 patients, SI showed a stronger correlation with skeletal muscle area (SMA) (r = 0.537, P < 0.001) than with the Scr/cystatin C ratio (r = 0.469, P < 0.001) and Scr (r = 0.447, P < 0.001). The low SI group had a lower SMA, lower preoperative haemoglobin, a higher prevalence of sarcopenia and experienced more postoperative complications compared with the high SI group (all P < 0.001). Multivariate logistic regression analysis showed that the independent risk factors for overall complications were low preoperative haemoglobin, low SI, sarcopenia and American Society of Anesthesiologists grade ≥ 3.

CONCLUSION

This new SI is a simple and useful surrogate marker for estimating SMM, and is associated with outcomes after CRC surgery.

Knockdown of 14-kDa phosphohistidine phosphatase expression suppresses lung cancer cell growth in vivo possibly through inhibition of NF-κB signaling pathway

In previous study, we reported that 14-kDa phosphohistidine phosphatase (PHP14) was associated with lung cancer cell migration and invasion. We also found that the expression of PHP14 was markedly increased in a part of human lung cancer tissues. In this study, we investigated the impact of PHP14 knockdown on lung cancer cell tumorigenesis in vitro and in vivo, as well as the regulatory pathway. Depletion of endogenous PHP14 expression in lung cancer cells reduced colony formation activity of lung cancer cells in vitro and inhibited the xenograft tumor growth in vivo. Further experiments revealed that the NF-κB signal pathway inhibitor PDTC inhibited the upregulated expression of MMP9 induced by PHP14 overexpression in lung cancer cells. Furthermore, knockdown of PHP14 in lung cancer cells correlated with decreased expression of a subset of NF-κB-regulated genes, such as BCL-2, COX-2, MCP-1, MMP9 and VEGF-C, which play an important role in tumor progression. Together these data suggest that knockdown of PHP14 in lung cancer cells inhibits lung cancer tumor growth in vivo, possibly via regulating the NF-κB pathway.

A new hope: the immunotherapy in small cell lung cancer

Small cell lung cancer (SCLC) is of a high-grade malignancy with a high metastatic potential and poor clinical prognosis. Unfortunately, SCLC initially exhibits a good response to chemotherapy and radiation therapy, but inevitably, relapses decrease patients' chance of survival. Despite tremendous advances on the development of new chemotherapeutic agents, the prognosis of this disease remains poor. Immunotherapy plays a role in eliciting an anticancer response by modulating the patient's immune response of the tumor. Several studies have demonstrated that abnormal autoimmune regulation has a close relationship with SCLC. Thus, several immunotherapy trials are focused on SCLC treatment, including such approaches as immune checkpoints blockers, tumor vaccine, antigenic targets and adoptive cellular immunotherapy to benefit patients with SCLC. To date, the results from immunotherapy in SCLC have not been promising. For example, tumor vaccines have not been demonstrated to have a significant survival benefit. However, there have been many promising advances with immune checkpoints blockers. This review will provide a general overview of immunotherapy in SCLC. The landmark clinical trials in previous successful immunotherapy studies are summarized here. Finally, the challenges of immunotherapy in SCLC are discussed to facilitate the prediction of possible and valuable strategies for future therapy.

A flavonoid-based fluorescent probe enables the accurate quantification of human serum albumin by minimizing the interference from blood lipids

We herein provide a simple design strategy to improve the sensing specificity towards human serum albumin by incorporating a nitrobenzene quencher into a traditional polarity-sensitive probe in responding to the interference from blood lipids.

[Characteristics of Dix-Hallpike test induced nystagmus]

Objective:To retrospectively analyze the characteristics of 100 cases with Dix-Hallpike test induced nystagmus, especially the vertical downward component.Method:One hundred cases with positive Dix-Hallpike test between December 2017 and January 2018 were included in this study. Dix-Hallpike test and roll test were performed in all patients, and the max slow phase velocity (SPV), latency and duration of positional nystagmus were analyzed with SPSS 22.0 software.Result:According to the difference in the direction and duration of the nystagmus in the head-hanging position on Dix-Hallpike test, 100 patients were classified into 9 types. When only the vertical components were considered, 56 cases presented with bilateral or unilateral vertical upward component, among which 52 cases had unilateral torsional with vertical upward component, 4 cases had bilateral torsional with vertical upward component; 7 cases presented with vertically upward in one side and the vertically downward in the other side; 47 cases presented with bilateral or unilateral vertical downward component. In addition, 8 cases showed the reverse phase nystagmus. Of the 100 patients with positive Dix-hallpike, 20 cases were positive in roll test and 5 cases showing horizontal nystagmus and 15 cases showing torsional and vertical nystagmus.Conclusion:Vertical component in the positional nystagmus was common, and care should be taken to interpret the nystagmus into the underlying disorder.